]>
Commit | Line | Data |
---|---|---|
6d716ca8 | 1 | /* Fold a constant sub-tree into a single node for C-compiler |
080ea642 RS |
2 | Copyright (C) 1987, 1988, 1992, 1993, 1994, 1995, 1996, 1997, 1998, 1999, |
3 | 2000, 2001, 2002, 2003 Free Software Foundation, Inc. | |
6d716ca8 | 4 | |
1322177d | 5 | This file is part of GCC. |
6d716ca8 | 6 | |
1322177d LB |
7 | GCC is free software; you can redistribute it and/or modify it under |
8 | the terms of the GNU General Public License as published by the Free | |
9 | Software Foundation; either version 2, or (at your option) any later | |
10 | version. | |
6d716ca8 | 11 | |
1322177d LB |
12 | GCC is distributed in the hope that it will be useful, but WITHOUT ANY |
13 | WARRANTY; without even the implied warranty of MERCHANTABILITY or | |
14 | FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License | |
15 | for more details. | |
6d716ca8 RS |
16 | |
17 | You should have received a copy of the GNU General Public License | |
1322177d LB |
18 | along with GCC; see the file COPYING. If not, write to the Free |
19 | Software Foundation, 59 Temple Place - Suite 330, Boston, MA | |
20 | 02111-1307, USA. */ | |
6d716ca8 | 21 | |
6dc42e49 | 22 | /*@@ This file should be rewritten to use an arbitrary precision |
6d716ca8 RS |
23 | @@ representation for "struct tree_int_cst" and "struct tree_real_cst". |
24 | @@ Perhaps the routines could also be used for bc/dc, and made a lib. | |
25 | @@ The routines that translate from the ap rep should | |
26 | @@ warn if precision et. al. is lost. | |
27 | @@ This would also make life easier when this technology is used | |
28 | @@ for cross-compilers. */ | |
29 | ||
f8dac6eb | 30 | /* The entry points in this file are fold, size_int_wide, size_binop |
0da6f3db | 31 | and force_fit_type. |
6d716ca8 RS |
32 | |
33 | fold takes a tree as argument and returns a simplified tree. | |
34 | ||
35 | size_binop takes a tree code for an arithmetic operation | |
36 | and two operands that are trees, and produces a tree for the | |
37 | result, assuming the type comes from `sizetype'. | |
38 | ||
39 | size_int takes an integer value, and creates a tree constant | |
0da6f3db DE |
40 | with type from `sizetype'. |
41 | ||
42 | force_fit_type takes a constant and prior overflow indicator, and | |
43 | forces the value to fit the type. It returns an overflow indicator. */ | |
44 | ||
e9a25f70 | 45 | #include "config.h" |
2fde567e | 46 | #include "system.h" |
4977bab6 ZW |
47 | #include "coretypes.h" |
48 | #include "tm.h" | |
6d716ca8 RS |
49 | #include "flags.h" |
50 | #include "tree.h" | |
11ad4784 | 51 | #include "real.h" |
efe3eb65 | 52 | #include "rtl.h" |
0e9295cf | 53 | #include "expr.h" |
6baf1cc8 | 54 | #include "tm_p.h" |
10f0ad3d | 55 | #include "toplev.h" |
a3770a81 | 56 | #include "ggc.h" |
4c160717 | 57 | #include "hashtab.h" |
43577e6b | 58 | #include "langhooks.h" |
5dfa45d0 | 59 | #include "md5.h" |
6d716ca8 | 60 | |
fa8db1f7 AJ |
61 | static void encode (HOST_WIDE_INT *, unsigned HOST_WIDE_INT, HOST_WIDE_INT); |
62 | static void decode (HOST_WIDE_INT *, unsigned HOST_WIDE_INT *, HOST_WIDE_INT *); | |
63 | static bool negate_expr_p (tree); | |
64 | static tree negate_expr (tree); | |
65 | static tree split_tree (tree, enum tree_code, tree *, tree *, tree *, int); | |
66 | static tree associate_trees (tree, tree, enum tree_code, tree); | |
67 | static tree int_const_binop (enum tree_code, tree, tree, int); | |
68 | static tree const_binop (enum tree_code, tree, tree, int); | |
69 | static hashval_t size_htab_hash (const void *); | |
70 | static int size_htab_eq (const void *, const void *); | |
71 | static tree fold_convert (tree, tree); | |
72 | static enum tree_code invert_tree_comparison (enum tree_code); | |
73 | static enum tree_code swap_tree_comparison (enum tree_code); | |
74 | static int comparison_to_compcode (enum tree_code); | |
75 | static enum tree_code compcode_to_comparison (int); | |
76 | static int truth_value_p (enum tree_code); | |
77 | static int operand_equal_for_comparison_p (tree, tree, tree); | |
78 | static int twoval_comparison_p (tree, tree *, tree *, int *); | |
79 | static tree eval_subst (tree, tree, tree, tree, tree); | |
80 | static tree pedantic_omit_one_operand (tree, tree, tree); | |
81 | static tree distribute_bit_expr (enum tree_code, tree, tree, tree); | |
82 | static tree make_bit_field_ref (tree, tree, int, int, int); | |
83 | static tree optimize_bit_field_compare (enum tree_code, tree, tree, tree); | |
84 | static tree decode_field_reference (tree, HOST_WIDE_INT *, HOST_WIDE_INT *, | |
85 | enum machine_mode *, int *, int *, | |
86 | tree *, tree *); | |
87 | static int all_ones_mask_p (tree, int); | |
88 | static tree sign_bit_p (tree, tree); | |
89 | static int simple_operand_p (tree); | |
90 | static tree range_binop (enum tree_code, tree, tree, int, tree, int); | |
91 | static tree make_range (tree, int *, tree *, tree *); | |
92 | static tree build_range_check (tree, tree, int, tree, tree); | |
93 | static int merge_ranges (int *, tree *, tree *, int, tree, tree, int, tree, | |
94 | tree); | |
95 | static tree fold_range_test (tree); | |
96 | static tree unextend (tree, int, int, tree); | |
97 | static tree fold_truthop (enum tree_code, tree, tree, tree); | |
98 | static tree optimize_minmax_comparison (tree); | |
99 | static tree extract_muldiv (tree, tree, enum tree_code, tree); | |
100 | static tree extract_muldiv_1 (tree, tree, enum tree_code, tree); | |
101 | static tree strip_compound_expr (tree, tree); | |
102 | static int multiple_of_p (tree, tree, tree); | |
103 | static tree constant_boolean_node (int, tree); | |
104 | static int count_cond (tree, int); | |
105 | static tree fold_binary_op_with_conditional_arg (enum tree_code, tree, tree, | |
106 | tree, int); | |
107 | static bool fold_real_zero_addition_p (tree, tree, int); | |
108 | static tree fold_mathfn_compare (enum built_in_function, enum tree_code, | |
109 | tree, tree, tree); | |
110 | static tree fold_inf_compare (enum tree_code, tree, tree, tree); | |
37af03cb | 111 | static bool tree_swap_operands_p (tree, tree); |
dd3f0101 | 112 | |
8dcb27ed RS |
113 | /* The following constants represent a bit based encoding of GCC's |
114 | comparison operators. This encoding simplifies transformations | |
115 | on relational comparison operators, such as AND and OR. */ | |
116 | #define COMPCODE_FALSE 0 | |
117 | #define COMPCODE_LT 1 | |
118 | #define COMPCODE_EQ 2 | |
119 | #define COMPCODE_LE 3 | |
120 | #define COMPCODE_GT 4 | |
121 | #define COMPCODE_NE 5 | |
122 | #define COMPCODE_GE 6 | |
123 | #define COMPCODE_TRUE 7 | |
124 | ||
d4b60170 RK |
125 | /* We know that A1 + B1 = SUM1, using 2's complement arithmetic and ignoring |
126 | overflow. Suppose A, B and SUM have the same respective signs as A1, B1, | |
127 | and SUM1. Then this yields nonzero if overflow occurred during the | |
128 | addition. | |
129 | ||
130 | Overflow occurs if A and B have the same sign, but A and SUM differ in | |
131 | sign. Use `^' to test whether signs differ, and `< 0' to isolate the | |
132 | sign. */ | |
133 | #define OVERFLOW_SUM_SIGN(a, b, sum) ((~((a) ^ (b)) & ((a) ^ (sum))) < 0) | |
6d716ca8 | 134 | \f |
906c4e36 | 135 | /* To do constant folding on INTEGER_CST nodes requires two-word arithmetic. |
37bdb7e3 | 136 | We do that by representing the two-word integer in 4 words, with only |
d4b60170 RK |
137 | HOST_BITS_PER_WIDE_INT / 2 bits stored in each word, as a positive |
138 | number. The value of the word is LOWPART + HIGHPART * BASE. */ | |
37bdb7e3 TG |
139 | |
140 | #define LOWPART(x) \ | |
d4b60170 | 141 | ((x) & (((unsigned HOST_WIDE_INT) 1 << (HOST_BITS_PER_WIDE_INT / 2)) - 1)) |
37bdb7e3 | 142 | #define HIGHPART(x) \ |
d4b60170 RK |
143 | ((unsigned HOST_WIDE_INT) (x) >> HOST_BITS_PER_WIDE_INT / 2) |
144 | #define BASE ((unsigned HOST_WIDE_INT) 1 << HOST_BITS_PER_WIDE_INT / 2) | |
6d716ca8 | 145 | |
37bdb7e3 | 146 | /* Unpack a two-word integer into 4 words. |
906c4e36 | 147 | LOW and HI are the integer, as two `HOST_WIDE_INT' pieces. |
37bdb7e3 | 148 | WORDS points to the array of HOST_WIDE_INTs. */ |
6d716ca8 RS |
149 | |
150 | static void | |
fa8db1f7 | 151 | encode (HOST_WIDE_INT *words, unsigned HOST_WIDE_INT low, HOST_WIDE_INT hi) |
6d716ca8 | 152 | { |
37bdb7e3 TG |
153 | words[0] = LOWPART (low); |
154 | words[1] = HIGHPART (low); | |
155 | words[2] = LOWPART (hi); | |
156 | words[3] = HIGHPART (hi); | |
6d716ca8 RS |
157 | } |
158 | ||
37bdb7e3 TG |
159 | /* Pack an array of 4 words into a two-word integer. |
160 | WORDS points to the array of words. | |
906c4e36 | 161 | The integer is stored into *LOW and *HI as two `HOST_WIDE_INT' pieces. */ |
6d716ca8 RS |
162 | |
163 | static void | |
75040a04 AJ |
164 | decode (HOST_WIDE_INT *words, unsigned HOST_WIDE_INT *low, |
165 | HOST_WIDE_INT *hi) | |
6d716ca8 | 166 | { |
d4b60170 RK |
167 | *low = words[0] + words[1] * BASE; |
168 | *hi = words[2] + words[3] * BASE; | |
6d716ca8 RS |
169 | } |
170 | \f | |
d4b60170 RK |
171 | /* Make the integer constant T valid for its type by setting to 0 or 1 all |
172 | the bits in the constant that don't belong in the type. | |
173 | ||
174 | Return 1 if a signed overflow occurs, 0 otherwise. If OVERFLOW is | |
175 | nonzero, a signed overflow has already occurred in calculating T, so | |
efdc7e19 | 176 | propagate it. */ |
6d716ca8 | 177 | |
e0f776fb | 178 | int |
fa8db1f7 | 179 | force_fit_type (tree t, int overflow) |
6d716ca8 | 180 | { |
05bccae2 RK |
181 | unsigned HOST_WIDE_INT low; |
182 | HOST_WIDE_INT high; | |
183 | unsigned int prec; | |
6d716ca8 | 184 | |
649ff3b4 RK |
185 | if (TREE_CODE (t) == REAL_CST) |
186 | { | |
efdc7e19 RH |
187 | /* ??? Used to check for overflow here via CHECK_FLOAT_TYPE. |
188 | Consider doing it via real_convert now. */ | |
649ff3b4 RK |
189 | return overflow; |
190 | } | |
191 | ||
192 | else if (TREE_CODE (t) != INTEGER_CST) | |
ef2bf0c0 RS |
193 | return overflow; |
194 | ||
195 | low = TREE_INT_CST_LOW (t); | |
196 | high = TREE_INT_CST_HIGH (t); | |
42f769c1 | 197 | |
a5ac359a MM |
198 | if (POINTER_TYPE_P (TREE_TYPE (t)) |
199 | || TREE_CODE (TREE_TYPE (t)) == OFFSET_TYPE) | |
6d716ca8 | 200 | prec = POINTER_SIZE; |
ef2bf0c0 RS |
201 | else |
202 | prec = TYPE_PRECISION (TREE_TYPE (t)); | |
6d716ca8 RS |
203 | |
204 | /* First clear all bits that are beyond the type's precision. */ | |
205 | ||
906c4e36 | 206 | if (prec == 2 * HOST_BITS_PER_WIDE_INT) |
6d716ca8 | 207 | ; |
906c4e36 | 208 | else if (prec > HOST_BITS_PER_WIDE_INT) |
d4b60170 RK |
209 | TREE_INT_CST_HIGH (t) |
210 | &= ~((HOST_WIDE_INT) (-1) << (prec - HOST_BITS_PER_WIDE_INT)); | |
6d716ca8 RS |
211 | else |
212 | { | |
213 | TREE_INT_CST_HIGH (t) = 0; | |
906c4e36 | 214 | if (prec < HOST_BITS_PER_WIDE_INT) |
05bccae2 | 215 | TREE_INT_CST_LOW (t) &= ~((unsigned HOST_WIDE_INT) (-1) << prec); |
6d716ca8 RS |
216 | } |
217 | ||
44475138 RK |
218 | /* Unsigned types do not suffer sign extension or overflow unless they |
219 | are a sizetype. */ | |
220 | if (TREE_UNSIGNED (TREE_TYPE (t)) | |
221 | && ! (TREE_CODE (TREE_TYPE (t)) == INTEGER_TYPE | |
222 | && TYPE_IS_SIZETYPE (TREE_TYPE (t)))) | |
a7a05640 | 223 | return overflow; |
6d716ca8 | 224 | |
e0f776fb RS |
225 | /* If the value's sign bit is set, extend the sign. */ |
226 | if (prec != 2 * HOST_BITS_PER_WIDE_INT | |
906c4e36 | 227 | && (prec > HOST_BITS_PER_WIDE_INT |
05bccae2 RK |
228 | ? 0 != (TREE_INT_CST_HIGH (t) |
229 | & ((HOST_WIDE_INT) 1 | |
230 | << (prec - HOST_BITS_PER_WIDE_INT - 1))) | |
231 | : 0 != (TREE_INT_CST_LOW (t) | |
232 | & ((unsigned HOST_WIDE_INT) 1 << (prec - 1))))) | |
6d716ca8 RS |
233 | { |
234 | /* Value is negative: | |
235 | set to 1 all the bits that are outside this type's precision. */ | |
906c4e36 | 236 | if (prec > HOST_BITS_PER_WIDE_INT) |
d4b60170 RK |
237 | TREE_INT_CST_HIGH (t) |
238 | |= ((HOST_WIDE_INT) (-1) << (prec - HOST_BITS_PER_WIDE_INT)); | |
6d716ca8 RS |
239 | else |
240 | { | |
241 | TREE_INT_CST_HIGH (t) = -1; | |
906c4e36 | 242 | if (prec < HOST_BITS_PER_WIDE_INT) |
05bccae2 | 243 | TREE_INT_CST_LOW (t) |= ((unsigned HOST_WIDE_INT) (-1) << prec); |
6d716ca8 RS |
244 | } |
245 | } | |
e0f776fb | 246 | |
d4b60170 | 247 | /* Return nonzero if signed overflow occurred. */ |
e0f776fb RS |
248 | return |
249 | ((overflow | (low ^ TREE_INT_CST_LOW (t)) | (high ^ TREE_INT_CST_HIGH (t))) | |
250 | != 0); | |
6d716ca8 RS |
251 | } |
252 | \f | |
906c4e36 RK |
253 | /* Add two doubleword integers with doubleword result. |
254 | Each argument is given as two `HOST_WIDE_INT' pieces. | |
6d716ca8 | 255 | One argument is L1 and H1; the other, L2 and H2. |
37bdb7e3 | 256 | The value is stored as two `HOST_WIDE_INT' pieces in *LV and *HV. */ |
6d716ca8 | 257 | |
fe3e8e40 | 258 | int |
75040a04 AJ |
259 | add_double (unsigned HOST_WIDE_INT l1, HOST_WIDE_INT h1, |
260 | unsigned HOST_WIDE_INT l2, HOST_WIDE_INT h2, | |
261 | unsigned HOST_WIDE_INT *lv, HOST_WIDE_INT *hv) | |
6d716ca8 | 262 | { |
05bccae2 RK |
263 | unsigned HOST_WIDE_INT l; |
264 | HOST_WIDE_INT h; | |
6d716ca8 | 265 | |
37bdb7e3 | 266 | l = l1 + l2; |
05bccae2 | 267 | h = h1 + h2 + (l < l1); |
6d716ca8 | 268 | |
37bdb7e3 TG |
269 | *lv = l; |
270 | *hv = h; | |
d4b60170 | 271 | return OVERFLOW_SUM_SIGN (h1, h2, h); |
6d716ca8 RS |
272 | } |
273 | ||
906c4e36 | 274 | /* Negate a doubleword integer with doubleword result. |
fe3e8e40 | 275 | Return nonzero if the operation overflows, assuming it's signed. |
906c4e36 | 276 | The argument is given as two `HOST_WIDE_INT' pieces in L1 and H1. |
37bdb7e3 | 277 | The value is stored as two `HOST_WIDE_INT' pieces in *LV and *HV. */ |
6d716ca8 | 278 | |
fe3e8e40 | 279 | int |
75040a04 AJ |
280 | neg_double (unsigned HOST_WIDE_INT l1, HOST_WIDE_INT h1, |
281 | unsigned HOST_WIDE_INT *lv, HOST_WIDE_INT *hv) | |
6d716ca8 RS |
282 | { |
283 | if (l1 == 0) | |
284 | { | |
285 | *lv = 0; | |
286 | *hv = - h1; | |
e0f776fb | 287 | return (*hv & h1) < 0; |
6d716ca8 RS |
288 | } |
289 | else | |
290 | { | |
b6cc0a72 KH |
291 | *lv = -l1; |
292 | *hv = ~h1; | |
fe3e8e40 | 293 | return 0; |
6d716ca8 RS |
294 | } |
295 | } | |
296 | \f | |
906c4e36 | 297 | /* Multiply two doubleword integers with doubleword result. |
fe3e8e40 | 298 | Return nonzero if the operation overflows, assuming it's signed. |
906c4e36 | 299 | Each argument is given as two `HOST_WIDE_INT' pieces. |
6d716ca8 | 300 | One argument is L1 and H1; the other, L2 and H2. |
37bdb7e3 | 301 | The value is stored as two `HOST_WIDE_INT' pieces in *LV and *HV. */ |
6d716ca8 | 302 | |
fe3e8e40 | 303 | int |
75040a04 AJ |
304 | mul_double (unsigned HOST_WIDE_INT l1, HOST_WIDE_INT h1, |
305 | unsigned HOST_WIDE_INT l2, HOST_WIDE_INT h2, | |
306 | unsigned HOST_WIDE_INT *lv, HOST_WIDE_INT *hv) | |
6d716ca8 | 307 | { |
37bdb7e3 TG |
308 | HOST_WIDE_INT arg1[4]; |
309 | HOST_WIDE_INT arg2[4]; | |
310 | HOST_WIDE_INT prod[4 * 2]; | |
b3694847 SS |
311 | unsigned HOST_WIDE_INT carry; |
312 | int i, j, k; | |
05bccae2 RK |
313 | unsigned HOST_WIDE_INT toplow, neglow; |
314 | HOST_WIDE_INT tophigh, neghigh; | |
6d716ca8 | 315 | |
6d716ca8 RS |
316 | encode (arg1, l1, h1); |
317 | encode (arg2, l2, h2); | |
318 | ||
703ad42b | 319 | memset (prod, 0, sizeof prod); |
6d716ca8 | 320 | |
37bdb7e3 TG |
321 | for (i = 0; i < 4; i++) |
322 | { | |
323 | carry = 0; | |
324 | for (j = 0; j < 4; j++) | |
325 | { | |
326 | k = i + j; | |
327 | /* This product is <= 0xFFFE0001, the sum <= 0xFFFF0000. */ | |
328 | carry += arg1[i] * arg2[j]; | |
329 | /* Since prod[p] < 0xFFFF, this sum <= 0xFFFFFFFF. */ | |
330 | carry += prod[k]; | |
331 | prod[k] = LOWPART (carry); | |
332 | carry = HIGHPART (carry); | |
333 | } | |
334 | prod[i + 4] = carry; | |
335 | } | |
6d716ca8 | 336 | |
37bdb7e3 | 337 | decode (prod, lv, hv); /* This ignores prod[4] through prod[4*2-1] */ |
fe3e8e40 RS |
338 | |
339 | /* Check for overflow by calculating the top half of the answer in full; | |
340 | it should agree with the low half's sign bit. */ | |
b6cc0a72 | 341 | decode (prod + 4, &toplow, &tophigh); |
fe3e8e40 RS |
342 | if (h1 < 0) |
343 | { | |
344 | neg_double (l2, h2, &neglow, &neghigh); | |
345 | add_double (neglow, neghigh, toplow, tophigh, &toplow, &tophigh); | |
346 | } | |
347 | if (h2 < 0) | |
348 | { | |
349 | neg_double (l1, h1, &neglow, &neghigh); | |
350 | add_double (neglow, neghigh, toplow, tophigh, &toplow, &tophigh); | |
351 | } | |
352 | return (*hv < 0 ? ~(toplow & tophigh) : toplow | tophigh) != 0; | |
6d716ca8 RS |
353 | } |
354 | \f | |
906c4e36 | 355 | /* Shift the doubleword integer in L1, H1 left by COUNT places |
6d716ca8 RS |
356 | keeping only PREC bits of result. |
357 | Shift right if COUNT is negative. | |
358 | ARITH nonzero specifies arithmetic shifting; otherwise use logical shift. | |
906c4e36 | 359 | Store the value as two `HOST_WIDE_INT' pieces in *LV and *HV. */ |
6d716ca8 | 360 | |
e0f776fb | 361 | void |
75040a04 AJ |
362 | lshift_double (unsigned HOST_WIDE_INT l1, HOST_WIDE_INT h1, |
363 | HOST_WIDE_INT count, unsigned int prec, | |
364 | unsigned HOST_WIDE_INT *lv, HOST_WIDE_INT *hv, int arith) | |
6d716ca8 | 365 | { |
11b161d0 JW |
366 | unsigned HOST_WIDE_INT signmask; |
367 | ||
6d716ca8 RS |
368 | if (count < 0) |
369 | { | |
b6cc0a72 | 370 | rshift_double (l1, h1, -count, prec, lv, hv, arith); |
e0f776fb | 371 | return; |
6d716ca8 | 372 | } |
b6cc0a72 | 373 | |
3d1877b1 RK |
374 | #ifdef SHIFT_COUNT_TRUNCATED |
375 | if (SHIFT_COUNT_TRUNCATED) | |
376 | count %= prec; | |
377 | #endif | |
6d716ca8 | 378 | |
cb0a34c4 JW |
379 | if (count >= 2 * HOST_BITS_PER_WIDE_INT) |
380 | { | |
381 | /* Shifting by the host word size is undefined according to the | |
382 | ANSI standard, so we must handle this as a special case. */ | |
383 | *hv = 0; | |
384 | *lv = 0; | |
385 | } | |
386 | else if (count >= HOST_BITS_PER_WIDE_INT) | |
6d716ca8 | 387 | { |
05bccae2 | 388 | *hv = l1 << (count - HOST_BITS_PER_WIDE_INT); |
37bdb7e3 TG |
389 | *lv = 0; |
390 | } | |
391 | else | |
392 | { | |
393 | *hv = (((unsigned HOST_WIDE_INT) h1 << count) | |
05bccae2 RK |
394 | | (l1 >> (HOST_BITS_PER_WIDE_INT - count - 1) >> 1)); |
395 | *lv = l1 << count; | |
6d716ca8 | 396 | } |
11b161d0 JW |
397 | |
398 | /* Sign extend all bits that are beyond the precision. */ | |
399 | ||
400 | signmask = -((prec > HOST_BITS_PER_WIDE_INT | |
0316d49b | 401 | ? ((unsigned HOST_WIDE_INT) *hv |
dd3f0101 | 402 | >> (prec - HOST_BITS_PER_WIDE_INT - 1)) |
11b161d0 JW |
403 | : (*lv >> (prec - 1))) & 1); |
404 | ||
405 | if (prec >= 2 * HOST_BITS_PER_WIDE_INT) | |
406 | ; | |
407 | else if (prec >= HOST_BITS_PER_WIDE_INT) | |
408 | { | |
409 | *hv &= ~((HOST_WIDE_INT) (-1) << (prec - HOST_BITS_PER_WIDE_INT)); | |
410 | *hv |= signmask << (prec - HOST_BITS_PER_WIDE_INT); | |
411 | } | |
412 | else | |
413 | { | |
414 | *hv = signmask; | |
415 | *lv &= ~((unsigned HOST_WIDE_INT) (-1) << prec); | |
416 | *lv |= signmask << prec; | |
417 | } | |
6d716ca8 RS |
418 | } |
419 | ||
906c4e36 | 420 | /* Shift the doubleword integer in L1, H1 right by COUNT places |
6d716ca8 RS |
421 | keeping only PREC bits of result. COUNT must be positive. |
422 | ARITH nonzero specifies arithmetic shifting; otherwise use logical shift. | |
906c4e36 | 423 | Store the value as two `HOST_WIDE_INT' pieces in *LV and *HV. */ |
6d716ca8 RS |
424 | |
425 | void | |
75040a04 AJ |
426 | rshift_double (unsigned HOST_WIDE_INT l1, HOST_WIDE_INT h1, |
427 | HOST_WIDE_INT count, unsigned int prec, | |
428 | unsigned HOST_WIDE_INT *lv, HOST_WIDE_INT *hv, | |
fa8db1f7 | 429 | int arith) |
6d716ca8 | 430 | { |
37bdb7e3 | 431 | unsigned HOST_WIDE_INT signmask; |
05bccae2 | 432 | |
37bdb7e3 TG |
433 | signmask = (arith |
434 | ? -((unsigned HOST_WIDE_INT) h1 >> (HOST_BITS_PER_WIDE_INT - 1)) | |
435 | : 0); | |
6d716ca8 | 436 | |
3d1877b1 RK |
437 | #ifdef SHIFT_COUNT_TRUNCATED |
438 | if (SHIFT_COUNT_TRUNCATED) | |
439 | count %= prec; | |
440 | #endif | |
6d716ca8 | 441 | |
cb0a34c4 JW |
442 | if (count >= 2 * HOST_BITS_PER_WIDE_INT) |
443 | { | |
444 | /* Shifting by the host word size is undefined according to the | |
445 | ANSI standard, so we must handle this as a special case. */ | |
11b161d0 JW |
446 | *hv = 0; |
447 | *lv = 0; | |
cb0a34c4 JW |
448 | } |
449 | else if (count >= HOST_BITS_PER_WIDE_INT) | |
6d716ca8 | 450 | { |
11b161d0 JW |
451 | *hv = 0; |
452 | *lv = (unsigned HOST_WIDE_INT) h1 >> (count - HOST_BITS_PER_WIDE_INT); | |
37bdb7e3 TG |
453 | } |
454 | else | |
455 | { | |
11b161d0 | 456 | *hv = (unsigned HOST_WIDE_INT) h1 >> count; |
05bccae2 | 457 | *lv = ((l1 >> count) |
2fde567e | 458 | | ((unsigned HOST_WIDE_INT) h1 << (HOST_BITS_PER_WIDE_INT - count - 1) << 1)); |
11b161d0 JW |
459 | } |
460 | ||
461 | /* Zero / sign extend all bits that are beyond the precision. */ | |
462 | ||
463 | if (count >= (HOST_WIDE_INT)prec) | |
464 | { | |
465 | *hv = signmask; | |
466 | *lv = signmask; | |
467 | } | |
468 | else if ((prec - count) >= 2 * HOST_BITS_PER_WIDE_INT) | |
469 | ; | |
470 | else if ((prec - count) >= HOST_BITS_PER_WIDE_INT) | |
471 | { | |
472 | *hv &= ~((HOST_WIDE_INT) (-1) << (prec - count - HOST_BITS_PER_WIDE_INT)); | |
473 | *hv |= signmask << (prec - count - HOST_BITS_PER_WIDE_INT); | |
474 | } | |
475 | else | |
476 | { | |
477 | *hv = signmask; | |
478 | *lv &= ~((unsigned HOST_WIDE_INT) (-1) << (prec - count)); | |
479 | *lv |= signmask << (prec - count); | |
6d716ca8 | 480 | } |
6d716ca8 RS |
481 | } |
482 | \f | |
37bdb7e3 | 483 | /* Rotate the doubleword integer in L1, H1 left by COUNT places |
6d716ca8 RS |
484 | keeping only PREC bits of result. |
485 | Rotate right if COUNT is negative. | |
906c4e36 | 486 | Store the value as two `HOST_WIDE_INT' pieces in *LV and *HV. */ |
6d716ca8 RS |
487 | |
488 | void | |
75040a04 AJ |
489 | lrotate_double (unsigned HOST_WIDE_INT l1, HOST_WIDE_INT h1, |
490 | HOST_WIDE_INT count, unsigned int prec, | |
491 | unsigned HOST_WIDE_INT *lv, HOST_WIDE_INT *hv) | |
6d716ca8 | 492 | { |
05bccae2 RK |
493 | unsigned HOST_WIDE_INT s1l, s2l; |
494 | HOST_WIDE_INT s1h, s2h; | |
6d716ca8 | 495 | |
4d39710e | 496 | count %= prec; |
6d716ca8 | 497 | if (count < 0) |
4d39710e | 498 | count += prec; |
6d716ca8 | 499 | |
4d39710e RK |
500 | lshift_double (l1, h1, count, prec, &s1l, &s1h, 0); |
501 | rshift_double (l1, h1, prec - count, prec, &s2l, &s2h, 0); | |
502 | *lv = s1l | s2l; | |
503 | *hv = s1h | s2h; | |
6d716ca8 RS |
504 | } |
505 | ||
906c4e36 | 506 | /* Rotate the doubleword integer in L1, H1 left by COUNT places |
6d716ca8 | 507 | keeping only PREC bits of result. COUNT must be positive. |
906c4e36 | 508 | Store the value as two `HOST_WIDE_INT' pieces in *LV and *HV. */ |
6d716ca8 RS |
509 | |
510 | void | |
75040a04 AJ |
511 | rrotate_double (unsigned HOST_WIDE_INT l1, HOST_WIDE_INT h1, |
512 | HOST_WIDE_INT count, unsigned int prec, | |
513 | unsigned HOST_WIDE_INT *lv, HOST_WIDE_INT *hv) | |
6d716ca8 | 514 | { |
05bccae2 RK |
515 | unsigned HOST_WIDE_INT s1l, s2l; |
516 | HOST_WIDE_INT s1h, s2h; | |
6d716ca8 | 517 | |
4d39710e RK |
518 | count %= prec; |
519 | if (count < 0) | |
520 | count += prec; | |
6d716ca8 | 521 | |
4d39710e RK |
522 | rshift_double (l1, h1, count, prec, &s1l, &s1h, 0); |
523 | lshift_double (l1, h1, prec - count, prec, &s2l, &s2h, 0); | |
524 | *lv = s1l | s2l; | |
525 | *hv = s1h | s2h; | |
6d716ca8 RS |
526 | } |
527 | \f | |
906c4e36 | 528 | /* Divide doubleword integer LNUM, HNUM by doubleword integer LDEN, HDEN |
6d716ca8 RS |
529 | for a quotient (stored in *LQUO, *HQUO) and remainder (in *LREM, *HREM). |
530 | CODE is a tree code for a kind of division, one of | |
531 | TRUNC_DIV_EXPR, FLOOR_DIV_EXPR, CEIL_DIV_EXPR, ROUND_DIV_EXPR | |
532 | or EXACT_DIV_EXPR | |
4fe9b91c | 533 | It controls how the quotient is rounded to an integer. |
fe3e8e40 | 534 | Return nonzero if the operation overflows. |
6d716ca8 RS |
535 | UNS nonzero says do unsigned division. */ |
536 | ||
dbb5b3ce | 537 | int |
fa8db1f7 AJ |
538 | div_and_round_double (enum tree_code code, int uns, |
539 | unsigned HOST_WIDE_INT lnum_orig, /* num == numerator == dividend */ | |
540 | HOST_WIDE_INT hnum_orig, | |
541 | unsigned HOST_WIDE_INT lden_orig, /* den == denominator == divisor */ | |
75040a04 AJ |
542 | HOST_WIDE_INT hden_orig, |
543 | unsigned HOST_WIDE_INT *lquo, | |
fa8db1f7 AJ |
544 | HOST_WIDE_INT *hquo, unsigned HOST_WIDE_INT *lrem, |
545 | HOST_WIDE_INT *hrem) | |
6d716ca8 RS |
546 | { |
547 | int quo_neg = 0; | |
37bdb7e3 TG |
548 | HOST_WIDE_INT num[4 + 1]; /* extra element for scaling. */ |
549 | HOST_WIDE_INT den[4], quo[4]; | |
b3694847 | 550 | int i, j; |
37bdb7e3 | 551 | unsigned HOST_WIDE_INT work; |
05bccae2 RK |
552 | unsigned HOST_WIDE_INT carry = 0; |
553 | unsigned HOST_WIDE_INT lnum = lnum_orig; | |
b8eb43a2 | 554 | HOST_WIDE_INT hnum = hnum_orig; |
05bccae2 | 555 | unsigned HOST_WIDE_INT lden = lden_orig; |
b8eb43a2 | 556 | HOST_WIDE_INT hden = hden_orig; |
fe3e8e40 | 557 | int overflow = 0; |
6d716ca8 | 558 | |
05bccae2 | 559 | if (hden == 0 && lden == 0) |
956d6950 | 560 | overflow = 1, lden = 1; |
6d716ca8 | 561 | |
beb235f8 | 562 | /* Calculate quotient sign and convert operands to unsigned. */ |
b6cc0a72 | 563 | if (!uns) |
6d716ca8 | 564 | { |
fe3e8e40 | 565 | if (hnum < 0) |
6d716ca8 RS |
566 | { |
567 | quo_neg = ~ quo_neg; | |
fe3e8e40 | 568 | /* (minimum integer) / (-1) is the only overflow case. */ |
05bccae2 RK |
569 | if (neg_double (lnum, hnum, &lnum, &hnum) |
570 | && ((HOST_WIDE_INT) lden & hden) == -1) | |
fe3e8e40 | 571 | overflow = 1; |
6d716ca8 | 572 | } |
b6cc0a72 | 573 | if (hden < 0) |
6d716ca8 RS |
574 | { |
575 | quo_neg = ~ quo_neg; | |
fe3e8e40 | 576 | neg_double (lden, hden, &lden, &hden); |
6d716ca8 RS |
577 | } |
578 | } | |
579 | ||
580 | if (hnum == 0 && hden == 0) | |
581 | { /* single precision */ | |
582 | *hquo = *hrem = 0; | |
88ee2651 | 583 | /* This unsigned division rounds toward zero. */ |
05bccae2 | 584 | *lquo = lnum / lden; |
6d716ca8 RS |
585 | goto finish_up; |
586 | } | |
587 | ||
588 | if (hnum == 0) | |
589 | { /* trivial case: dividend < divisor */ | |
590 | /* hden != 0 already checked. */ | |
591 | *hquo = *lquo = 0; | |
592 | *hrem = hnum; | |
593 | *lrem = lnum; | |
594 | goto finish_up; | |
595 | } | |
596 | ||
703ad42b | 597 | memset (quo, 0, sizeof quo); |
6d716ca8 | 598 | |
703ad42b KG |
599 | memset (num, 0, sizeof num); /* to zero 9th element */ |
600 | memset (den, 0, sizeof den); | |
6d716ca8 | 601 | |
b6cc0a72 | 602 | encode (num, lnum, hnum); |
6d716ca8 RS |
603 | encode (den, lden, hden); |
604 | ||
37bdb7e3 | 605 | /* Special code for when the divisor < BASE. */ |
05bccae2 | 606 | if (hden == 0 && lden < (unsigned HOST_WIDE_INT) BASE) |
37bdb7e3 | 607 | { |
6d716ca8 | 608 | /* hnum != 0 already checked. */ |
37bdb7e3 | 609 | for (i = 4 - 1; i >= 0; i--) |
6d716ca8 | 610 | { |
37bdb7e3 | 611 | work = num[i] + carry * BASE; |
05bccae2 RK |
612 | quo[i] = work / lden; |
613 | carry = work % lden; | |
6d716ca8 RS |
614 | } |
615 | } | |
37bdb7e3 TG |
616 | else |
617 | { | |
618 | /* Full double precision division, | |
619 | with thanks to Don Knuth's "Seminumerical Algorithms". */ | |
05bccae2 RK |
620 | int num_hi_sig, den_hi_sig; |
621 | unsigned HOST_WIDE_INT quo_est, scale; | |
6d716ca8 | 622 | |
cc2902df | 623 | /* Find the highest nonzero divisor digit. */ |
b6cc0a72 KH |
624 | for (i = 4 - 1;; i--) |
625 | if (den[i] != 0) | |
626 | { | |
627 | den_hi_sig = i; | |
628 | break; | |
629 | } | |
37bdb7e3 | 630 | |
05bccae2 RK |
631 | /* Insure that the first digit of the divisor is at least BASE/2. |
632 | This is required by the quotient digit estimation algorithm. */ | |
6d716ca8 | 633 | |
05bccae2 RK |
634 | scale = BASE / (den[den_hi_sig] + 1); |
635 | if (scale > 1) | |
636 | { /* scale divisor and dividend */ | |
637 | carry = 0; | |
638 | for (i = 0; i <= 4 - 1; i++) | |
639 | { | |
640 | work = (num[i] * scale) + carry; | |
641 | num[i] = LOWPART (work); | |
642 | carry = HIGHPART (work); | |
643 | } | |
6d716ca8 | 644 | |
05bccae2 RK |
645 | num[4] = carry; |
646 | carry = 0; | |
647 | for (i = 0; i <= 4 - 1; i++) | |
648 | { | |
649 | work = (den[i] * scale) + carry; | |
650 | den[i] = LOWPART (work); | |
651 | carry = HIGHPART (work); | |
652 | if (den[i] != 0) den_hi_sig = i; | |
653 | } | |
654 | } | |
6d716ca8 | 655 | |
05bccae2 | 656 | num_hi_sig = 4; |
6d716ca8 | 657 | |
05bccae2 RK |
658 | /* Main loop */ |
659 | for (i = num_hi_sig - den_hi_sig - 1; i >= 0; i--) | |
6d716ca8 | 660 | { |
05bccae2 RK |
661 | /* Guess the next quotient digit, quo_est, by dividing the first |
662 | two remaining dividend digits by the high order quotient digit. | |
663 | quo_est is never low and is at most 2 high. */ | |
664 | unsigned HOST_WIDE_INT tmp; | |
665 | ||
666 | num_hi_sig = i + den_hi_sig + 1; | |
667 | work = num[num_hi_sig] * BASE + num[num_hi_sig - 1]; | |
668 | if (num[num_hi_sig] != den[den_hi_sig]) | |
669 | quo_est = work / den[den_hi_sig]; | |
670 | else | |
671 | quo_est = BASE - 1; | |
6d716ca8 | 672 | |
6d2f8887 | 673 | /* Refine quo_est so it's usually correct, and at most one high. */ |
05bccae2 RK |
674 | tmp = work - quo_est * den[den_hi_sig]; |
675 | if (tmp < BASE | |
676 | && (den[den_hi_sig - 1] * quo_est | |
677 | > (tmp * BASE + num[num_hi_sig - 2]))) | |
678 | quo_est--; | |
6d716ca8 | 679 | |
05bccae2 RK |
680 | /* Try QUO_EST as the quotient digit, by multiplying the |
681 | divisor by QUO_EST and subtracting from the remaining dividend. | |
682 | Keep in mind that QUO_EST is the I - 1st digit. */ | |
683 | ||
684 | carry = 0; | |
6d716ca8 RS |
685 | for (j = 0; j <= den_hi_sig; j++) |
686 | { | |
05bccae2 | 687 | work = quo_est * den[j] + carry; |
37bdb7e3 | 688 | carry = HIGHPART (work); |
05bccae2 | 689 | work = num[i + j] - LOWPART (work); |
37bdb7e3 | 690 | num[i + j] = LOWPART (work); |
05bccae2 | 691 | carry += HIGHPART (work) != 0; |
6d716ca8 | 692 | } |
6d716ca8 | 693 | |
05bccae2 RK |
694 | /* If quo_est was high by one, then num[i] went negative and |
695 | we need to correct things. */ | |
0316d49b | 696 | if (num[num_hi_sig] < (HOST_WIDE_INT) carry) |
05bccae2 RK |
697 | { |
698 | quo_est--; | |
699 | carry = 0; /* add divisor back in */ | |
700 | for (j = 0; j <= den_hi_sig; j++) | |
701 | { | |
702 | work = num[i + j] + den[j] + carry; | |
703 | carry = HIGHPART (work); | |
704 | num[i + j] = LOWPART (work); | |
705 | } | |
706 | ||
707 | num [num_hi_sig] += carry; | |
708 | } | |
709 | ||
710 | /* Store the quotient digit. */ | |
711 | quo[i] = quo_est; | |
712 | } | |
6d716ca8 | 713 | } |
6d716ca8 RS |
714 | |
715 | decode (quo, lquo, hquo); | |
716 | ||
717 | finish_up: | |
938d968e | 718 | /* If result is negative, make it so. */ |
6d716ca8 RS |
719 | if (quo_neg) |
720 | neg_double (*lquo, *hquo, lquo, hquo); | |
721 | ||
722 | /* compute trial remainder: rem = num - (quo * den) */ | |
723 | mul_double (*lquo, *hquo, lden_orig, hden_orig, lrem, hrem); | |
724 | neg_double (*lrem, *hrem, lrem, hrem); | |
725 | add_double (lnum_orig, hnum_orig, *lrem, *hrem, lrem, hrem); | |
726 | ||
727 | switch (code) | |
728 | { | |
729 | case TRUNC_DIV_EXPR: | |
730 | case TRUNC_MOD_EXPR: /* round toward zero */ | |
731 | case EXACT_DIV_EXPR: /* for this one, it shouldn't matter */ | |
fe3e8e40 | 732 | return overflow; |
6d716ca8 RS |
733 | |
734 | case FLOOR_DIV_EXPR: | |
735 | case FLOOR_MOD_EXPR: /* round toward negative infinity */ | |
736 | if (quo_neg && (*lrem != 0 || *hrem != 0)) /* ratio < 0 && rem != 0 */ | |
737 | { | |
738 | /* quo = quo - 1; */ | |
906c4e36 RK |
739 | add_double (*lquo, *hquo, (HOST_WIDE_INT) -1, (HOST_WIDE_INT) -1, |
740 | lquo, hquo); | |
6d716ca8 | 741 | } |
05bccae2 RK |
742 | else |
743 | return overflow; | |
6d716ca8 RS |
744 | break; |
745 | ||
746 | case CEIL_DIV_EXPR: | |
747 | case CEIL_MOD_EXPR: /* round toward positive infinity */ | |
748 | if (!quo_neg && (*lrem != 0 || *hrem != 0)) /* ratio > 0 && rem != 0 */ | |
749 | { | |
906c4e36 RK |
750 | add_double (*lquo, *hquo, (HOST_WIDE_INT) 1, (HOST_WIDE_INT) 0, |
751 | lquo, hquo); | |
6d716ca8 | 752 | } |
05bccae2 RK |
753 | else |
754 | return overflow; | |
6d716ca8 | 755 | break; |
b6cc0a72 | 756 | |
6d716ca8 RS |
757 | case ROUND_DIV_EXPR: |
758 | case ROUND_MOD_EXPR: /* round to closest integer */ | |
759 | { | |
05bccae2 RK |
760 | unsigned HOST_WIDE_INT labs_rem = *lrem; |
761 | HOST_WIDE_INT habs_rem = *hrem; | |
762 | unsigned HOST_WIDE_INT labs_den = lden, ltwice; | |
763 | HOST_WIDE_INT habs_den = hden, htwice; | |
764 | ||
f9da5064 | 765 | /* Get absolute values. */ |
05bccae2 RK |
766 | if (*hrem < 0) |
767 | neg_double (*lrem, *hrem, &labs_rem, &habs_rem); | |
768 | if (hden < 0) | |
769 | neg_double (lden, hden, &labs_den, &habs_den); | |
770 | ||
771 | /* If (2 * abs (lrem) >= abs (lden)) */ | |
906c4e36 RK |
772 | mul_double ((HOST_WIDE_INT) 2, (HOST_WIDE_INT) 0, |
773 | labs_rem, habs_rem, <wice, &htwice); | |
05bccae2 | 774 | |
906c4e36 RK |
775 | if (((unsigned HOST_WIDE_INT) habs_den |
776 | < (unsigned HOST_WIDE_INT) htwice) | |
777 | || (((unsigned HOST_WIDE_INT) habs_den | |
778 | == (unsigned HOST_WIDE_INT) htwice) | |
05bccae2 | 779 | && (labs_den < ltwice))) |
6d716ca8 RS |
780 | { |
781 | if (*hquo < 0) | |
782 | /* quo = quo - 1; */ | |
906c4e36 RK |
783 | add_double (*lquo, *hquo, |
784 | (HOST_WIDE_INT) -1, (HOST_WIDE_INT) -1, lquo, hquo); | |
6d716ca8 RS |
785 | else |
786 | /* quo = quo + 1; */ | |
906c4e36 RK |
787 | add_double (*lquo, *hquo, (HOST_WIDE_INT) 1, (HOST_WIDE_INT) 0, |
788 | lquo, hquo); | |
6d716ca8 | 789 | } |
05bccae2 RK |
790 | else |
791 | return overflow; | |
6d716ca8 RS |
792 | } |
793 | break; | |
794 | ||
795 | default: | |
796 | abort (); | |
797 | } | |
798 | ||
799 | /* compute true remainder: rem = num - (quo * den) */ | |
800 | mul_double (*lquo, *hquo, lden_orig, hden_orig, lrem, hrem); | |
801 | neg_double (*lrem, *hrem, lrem, hrem); | |
802 | add_double (lnum_orig, hnum_orig, *lrem, *hrem, lrem, hrem); | |
fe3e8e40 | 803 | return overflow; |
6d716ca8 RS |
804 | } |
805 | \f | |
080ea642 RS |
806 | /* Determine whether an expression T can be cheaply negated using |
807 | the function negate_expr. */ | |
808 | ||
809 | static bool | |
fa8db1f7 | 810 | negate_expr_p (tree t) |
080ea642 RS |
811 | { |
812 | unsigned HOST_WIDE_INT val; | |
813 | unsigned int prec; | |
814 | tree type; | |
815 | ||
816 | if (t == 0) | |
817 | return false; | |
818 | ||
819 | type = TREE_TYPE (t); | |
820 | ||
821 | STRIP_SIGN_NOPS (t); | |
822 | switch (TREE_CODE (t)) | |
823 | { | |
824 | case INTEGER_CST: | |
825 | if (TREE_UNSIGNED (type)) | |
826 | return false; | |
827 | ||
828 | /* Check that -CST will not overflow type. */ | |
829 | prec = TYPE_PRECISION (type); | |
830 | if (prec > HOST_BITS_PER_WIDE_INT) | |
831 | { | |
832 | if (TREE_INT_CST_LOW (t) != 0) | |
833 | return true; | |
834 | prec -= HOST_BITS_PER_WIDE_INT; | |
835 | val = TREE_INT_CST_HIGH (t); | |
836 | } | |
837 | else | |
838 | val = TREE_INT_CST_LOW (t); | |
839 | if (prec < HOST_BITS_PER_WIDE_INT) | |
840 | val &= ((unsigned HOST_WIDE_INT) 1 << prec) - 1; | |
841 | return val != ((unsigned HOST_WIDE_INT) 1 << (prec - 1)); | |
842 | ||
843 | case REAL_CST: | |
844 | case NEGATE_EXPR: | |
080ea642 RS |
845 | return true; |
846 | ||
02a1994c RS |
847 | case MINUS_EXPR: |
848 | /* We can't turn -(A-B) into B-A when we honor signed zeros. */ | |
849 | return ! FLOAT_TYPE_P (type) || flag_unsafe_math_optimizations; | |
850 | ||
8ab49fef RS |
851 | case MULT_EXPR: |
852 | if (TREE_UNSIGNED (TREE_TYPE (t))) | |
853 | break; | |
854 | ||
855 | /* Fall through. */ | |
856 | ||
857 | case RDIV_EXPR: | |
858 | if (! HONOR_SIGN_DEPENDENT_ROUNDING (TYPE_MODE (TREE_TYPE (t)))) | |
859 | return negate_expr_p (TREE_OPERAND (t, 1)) | |
860 | || negate_expr_p (TREE_OPERAND (t, 0)); | |
861 | break; | |
862 | ||
080ea642 RS |
863 | default: |
864 | break; | |
865 | } | |
866 | return false; | |
867 | } | |
868 | ||
1baa375f RK |
869 | /* Given T, an expression, return the negation of T. Allow for T to be |
870 | null, in which case return null. */ | |
6d716ca8 | 871 | |
1baa375f | 872 | static tree |
fa8db1f7 | 873 | negate_expr (tree t) |
1baa375f RK |
874 | { |
875 | tree type; | |
876 | tree tem; | |
877 | ||
878 | if (t == 0) | |
879 | return 0; | |
880 | ||
881 | type = TREE_TYPE (t); | |
882 | STRIP_SIGN_NOPS (t); | |
883 | ||
884 | switch (TREE_CODE (t)) | |
885 | { | |
886 | case INTEGER_CST: | |
1baa375f RK |
887 | if (! TREE_UNSIGNED (type) |
888 | && 0 != (tem = fold (build1 (NEGATE_EXPR, type, t))) | |
889 | && ! TREE_OVERFLOW (tem)) | |
890 | return tem; | |
891 | break; | |
892 | ||
8ab49fef RS |
893 | case REAL_CST: |
894 | tem = build_real (type, REAL_VALUE_NEGATE (TREE_REAL_CST (t))); | |
895 | /* Two's complement FP formats, such as c4x, may overflow. */ | |
896 | if (! TREE_OVERFLOW (tem)) | |
897 | return convert (type, tem); | |
898 | break; | |
899 | ||
1baa375f RK |
900 | case NEGATE_EXPR: |
901 | return convert (type, TREE_OPERAND (t, 0)); | |
902 | ||
903 | case MINUS_EXPR: | |
904 | /* - (A - B) -> B - A */ | |
de6c5979 | 905 | if (! FLOAT_TYPE_P (type) || flag_unsafe_math_optimizations) |
1baa375f RK |
906 | return convert (type, |
907 | fold (build (MINUS_EXPR, TREE_TYPE (t), | |
908 | TREE_OPERAND (t, 1), | |
909 | TREE_OPERAND (t, 0)))); | |
910 | break; | |
911 | ||
8ab49fef RS |
912 | case MULT_EXPR: |
913 | if (TREE_UNSIGNED (TREE_TYPE (t))) | |
914 | break; | |
915 | ||
916 | /* Fall through. */ | |
917 | ||
918 | case RDIV_EXPR: | |
919 | if (! HONOR_SIGN_DEPENDENT_ROUNDING (TYPE_MODE (TREE_TYPE (t)))) | |
920 | { | |
921 | tem = TREE_OPERAND (t, 1); | |
922 | if (negate_expr_p (tem)) | |
923 | return convert (type, | |
924 | fold (build (TREE_CODE (t), TREE_TYPE (t), | |
925 | TREE_OPERAND (t, 0), | |
926 | negate_expr (tem)))); | |
927 | tem = TREE_OPERAND (t, 0); | |
928 | if (negate_expr_p (tem)) | |
929 | return convert (type, | |
930 | fold (build (TREE_CODE (t), TREE_TYPE (t), | |
931 | negate_expr (tem), | |
932 | TREE_OPERAND (t, 1)))); | |
933 | } | |
934 | break; | |
935 | ||
1baa375f RK |
936 | default: |
937 | break; | |
938 | } | |
939 | ||
a094954e | 940 | return convert (type, fold (build1 (NEGATE_EXPR, TREE_TYPE (t), t))); |
1baa375f RK |
941 | } |
942 | \f | |
943 | /* Split a tree IN into a constant, literal and variable parts that could be | |
944 | combined with CODE to make IN. "constant" means an expression with | |
945 | TREE_CONSTANT but that isn't an actual constant. CODE must be a | |
946 | commutative arithmetic operation. Store the constant part into *CONP, | |
cff27795 | 947 | the literal in *LITP and return the variable part. If a part isn't |
1baa375f RK |
948 | present, set it to null. If the tree does not decompose in this way, |
949 | return the entire tree as the variable part and the other parts as null. | |
950 | ||
951 | If CODE is PLUS_EXPR we also split trees that use MINUS_EXPR. In that | |
cff27795 EB |
952 | case, we negate an operand that was subtracted. Except if it is a |
953 | literal for which we use *MINUS_LITP instead. | |
954 | ||
955 | If NEGATE_P is true, we are negating all of IN, again except a literal | |
956 | for which we use *MINUS_LITP instead. | |
1baa375f RK |
957 | |
958 | If IN is itself a literal or constant, return it as appropriate. | |
959 | ||
960 | Note that we do not guarantee that any of the three values will be the | |
961 | same type as IN, but they will have the same signedness and mode. */ | |
962 | ||
963 | static tree | |
75040a04 AJ |
964 | split_tree (tree in, enum tree_code code, tree *conp, tree *litp, |
965 | tree *minus_litp, int negate_p) | |
6d716ca8 | 966 | { |
1baa375f RK |
967 | tree var = 0; |
968 | ||
6d716ca8 | 969 | *conp = 0; |
1baa375f | 970 | *litp = 0; |
cff27795 | 971 | *minus_litp = 0; |
1baa375f | 972 | |
30f7a378 | 973 | /* Strip any conversions that don't change the machine mode or signedness. */ |
1baa375f RK |
974 | STRIP_SIGN_NOPS (in); |
975 | ||
976 | if (TREE_CODE (in) == INTEGER_CST || TREE_CODE (in) == REAL_CST) | |
977 | *litp = in; | |
1baa375f RK |
978 | else if (TREE_CODE (in) == code |
979 | || (! FLOAT_TYPE_P (TREE_TYPE (in)) | |
980 | /* We can associate addition and subtraction together (even | |
981 | though the C standard doesn't say so) for integers because | |
982 | the value is not affected. For reals, the value might be | |
983 | affected, so we can't. */ | |
984 | && ((code == PLUS_EXPR && TREE_CODE (in) == MINUS_EXPR) | |
985 | || (code == MINUS_EXPR && TREE_CODE (in) == PLUS_EXPR)))) | |
986 | { | |
987 | tree op0 = TREE_OPERAND (in, 0); | |
988 | tree op1 = TREE_OPERAND (in, 1); | |
989 | int neg1_p = TREE_CODE (in) == MINUS_EXPR; | |
990 | int neg_litp_p = 0, neg_conp_p = 0, neg_var_p = 0; | |
991 | ||
992 | /* First see if either of the operands is a literal, then a constant. */ | |
993 | if (TREE_CODE (op0) == INTEGER_CST || TREE_CODE (op0) == REAL_CST) | |
994 | *litp = op0, op0 = 0; | |
995 | else if (TREE_CODE (op1) == INTEGER_CST || TREE_CODE (op1) == REAL_CST) | |
996 | *litp = op1, neg_litp_p = neg1_p, op1 = 0; | |
997 | ||
998 | if (op0 != 0 && TREE_CONSTANT (op0)) | |
999 | *conp = op0, op0 = 0; | |
1000 | else if (op1 != 0 && TREE_CONSTANT (op1)) | |
1001 | *conp = op1, neg_conp_p = neg1_p, op1 = 0; | |
1002 | ||
1003 | /* If we haven't dealt with either operand, this is not a case we can | |
30f7a378 | 1004 | decompose. Otherwise, VAR is either of the ones remaining, if any. */ |
1baa375f RK |
1005 | if (op0 != 0 && op1 != 0) |
1006 | var = in; | |
1007 | else if (op0 != 0) | |
1008 | var = op0; | |
1009 | else | |
1010 | var = op1, neg_var_p = neg1_p; | |
6d716ca8 | 1011 | |
1baa375f | 1012 | /* Now do any needed negations. */ |
cff27795 EB |
1013 | if (neg_litp_p) |
1014 | *minus_litp = *litp, *litp = 0; | |
1015 | if (neg_conp_p) | |
1016 | *conp = negate_expr (*conp); | |
1017 | if (neg_var_p) | |
1018 | var = negate_expr (var); | |
1baa375f | 1019 | } |
1796dff4 RH |
1020 | else if (TREE_CONSTANT (in)) |
1021 | *conp = in; | |
1baa375f RK |
1022 | else |
1023 | var = in; | |
1024 | ||
1025 | if (negate_p) | |
6d716ca8 | 1026 | { |
cff27795 EB |
1027 | if (*litp) |
1028 | *minus_litp = *litp, *litp = 0; | |
1029 | else if (*minus_litp) | |
1030 | *litp = *minus_litp, *minus_litp = 0; | |
1baa375f | 1031 | *conp = negate_expr (*conp); |
cff27795 | 1032 | var = negate_expr (var); |
6d716ca8 | 1033 | } |
1baa375f RK |
1034 | |
1035 | return var; | |
1036 | } | |
1037 | ||
1038 | /* Re-associate trees split by the above function. T1 and T2 are either | |
1039 | expressions to associate or null. Return the new expression, if any. If | |
cff27795 | 1040 | we build an operation, do it in TYPE and with CODE. */ |
1baa375f RK |
1041 | |
1042 | static tree | |
fa8db1f7 | 1043 | associate_trees (tree t1, tree t2, enum tree_code code, tree type) |
1baa375f | 1044 | { |
1baa375f RK |
1045 | if (t1 == 0) |
1046 | return t2; | |
1047 | else if (t2 == 0) | |
1048 | return t1; | |
1049 | ||
1baa375f RK |
1050 | /* If either input is CODE, a PLUS_EXPR, or a MINUS_EXPR, don't |
1051 | try to fold this since we will have infinite recursion. But do | |
1052 | deal with any NEGATE_EXPRs. */ | |
1053 | if (TREE_CODE (t1) == code || TREE_CODE (t2) == code | |
1054 | || TREE_CODE (t1) == MINUS_EXPR || TREE_CODE (t2) == MINUS_EXPR) | |
1055 | { | |
1bed5ee3 JJ |
1056 | if (code == PLUS_EXPR) |
1057 | { | |
1058 | if (TREE_CODE (t1) == NEGATE_EXPR) | |
1059 | return build (MINUS_EXPR, type, convert (type, t2), | |
1060 | convert (type, TREE_OPERAND (t1, 0))); | |
1061 | else if (TREE_CODE (t2) == NEGATE_EXPR) | |
1062 | return build (MINUS_EXPR, type, convert (type, t1), | |
1063 | convert (type, TREE_OPERAND (t2, 0))); | |
1064 | } | |
1065 | return build (code, type, convert (type, t1), convert (type, t2)); | |
1baa375f RK |
1066 | } |
1067 | ||
1068 | return fold (build (code, type, convert (type, t1), convert (type, t2))); | |
6d716ca8 RS |
1069 | } |
1070 | \f | |
e9a25f70 | 1071 | /* Combine two integer constants ARG1 and ARG2 under operation CODE |
6d716ca8 | 1072 | to produce a new constant. |
91d33e36 | 1073 | |
4c160717 | 1074 | If NOTRUNC is nonzero, do not truncate the result to fit the data type. */ |
6d716ca8 | 1075 | |
6d716ca8 | 1076 | static tree |
fa8db1f7 | 1077 | int_const_binop (enum tree_code code, tree arg1, tree arg2, int notrunc) |
6d716ca8 | 1078 | { |
05bccae2 RK |
1079 | unsigned HOST_WIDE_INT int1l, int2l; |
1080 | HOST_WIDE_INT int1h, int2h; | |
1081 | unsigned HOST_WIDE_INT low; | |
1082 | HOST_WIDE_INT hi; | |
1083 | unsigned HOST_WIDE_INT garbagel; | |
1084 | HOST_WIDE_INT garbageh; | |
b3694847 | 1085 | tree t; |
4c160717 RK |
1086 | tree type = TREE_TYPE (arg1); |
1087 | int uns = TREE_UNSIGNED (type); | |
1088 | int is_sizetype | |
1089 | = (TREE_CODE (type) == INTEGER_TYPE && TYPE_IS_SIZETYPE (type)); | |
e9a25f70 JL |
1090 | int overflow = 0; |
1091 | int no_overflow = 0; | |
3dedc65a | 1092 | |
e9a25f70 JL |
1093 | int1l = TREE_INT_CST_LOW (arg1); |
1094 | int1h = TREE_INT_CST_HIGH (arg1); | |
1095 | int2l = TREE_INT_CST_LOW (arg2); | |
1096 | int2h = TREE_INT_CST_HIGH (arg2); | |
1097 | ||
1098 | switch (code) | |
6d716ca8 | 1099 | { |
e9a25f70 JL |
1100 | case BIT_IOR_EXPR: |
1101 | low = int1l | int2l, hi = int1h | int2h; | |
1102 | break; | |
6d716ca8 | 1103 | |
e9a25f70 JL |
1104 | case BIT_XOR_EXPR: |
1105 | low = int1l ^ int2l, hi = int1h ^ int2h; | |
1106 | break; | |
6d716ca8 | 1107 | |
e9a25f70 JL |
1108 | case BIT_AND_EXPR: |
1109 | low = int1l & int2l, hi = int1h & int2h; | |
1110 | break; | |
6d716ca8 | 1111 | |
e9a25f70 | 1112 | case RSHIFT_EXPR: |
b6cc0a72 | 1113 | int2l = -int2l; |
e9a25f70 JL |
1114 | case LSHIFT_EXPR: |
1115 | /* It's unclear from the C standard whether shifts can overflow. | |
1116 | The following code ignores overflow; perhaps a C standard | |
1117 | interpretation ruling is needed. */ | |
4c160717 | 1118 | lshift_double (int1l, int1h, int2l, TYPE_PRECISION (type), |
770ae6cc | 1119 | &low, &hi, !uns); |
e9a25f70 JL |
1120 | no_overflow = 1; |
1121 | break; | |
6d716ca8 | 1122 | |
e9a25f70 JL |
1123 | case RROTATE_EXPR: |
1124 | int2l = - int2l; | |
1125 | case LROTATE_EXPR: | |
4c160717 | 1126 | lrotate_double (int1l, int1h, int2l, TYPE_PRECISION (type), |
e9a25f70 JL |
1127 | &low, &hi); |
1128 | break; | |
6d716ca8 | 1129 | |
e9a25f70 JL |
1130 | case PLUS_EXPR: |
1131 | overflow = add_double (int1l, int1h, int2l, int2h, &low, &hi); | |
1132 | break; | |
6d716ca8 | 1133 | |
e9a25f70 JL |
1134 | case MINUS_EXPR: |
1135 | neg_double (int2l, int2h, &low, &hi); | |
1136 | add_double (int1l, int1h, low, hi, &low, &hi); | |
d4b60170 | 1137 | overflow = OVERFLOW_SUM_SIGN (hi, int2h, int1h); |
e9a25f70 | 1138 | break; |
6d716ca8 | 1139 | |
e9a25f70 JL |
1140 | case MULT_EXPR: |
1141 | overflow = mul_double (int1l, int1h, int2l, int2h, &low, &hi); | |
1142 | break; | |
6d716ca8 | 1143 | |
e9a25f70 JL |
1144 | case TRUNC_DIV_EXPR: |
1145 | case FLOOR_DIV_EXPR: case CEIL_DIV_EXPR: | |
1146 | case EXACT_DIV_EXPR: | |
1147 | /* This is a shortcut for a common special case. */ | |
05bccae2 | 1148 | if (int2h == 0 && (HOST_WIDE_INT) int2l > 0 |
e9a25f70 JL |
1149 | && ! TREE_CONSTANT_OVERFLOW (arg1) |
1150 | && ! TREE_CONSTANT_OVERFLOW (arg2) | |
05bccae2 | 1151 | && int1h == 0 && (HOST_WIDE_INT) int1l >= 0) |
e9a25f70 JL |
1152 | { |
1153 | if (code == CEIL_DIV_EXPR) | |
1154 | int1l += int2l - 1; | |
05bccae2 | 1155 | |
e9a25f70 | 1156 | low = int1l / int2l, hi = 0; |
6d716ca8 | 1157 | break; |
e9a25f70 | 1158 | } |
6d716ca8 | 1159 | |
30f7a378 | 1160 | /* ... fall through ... */ |
6d716ca8 | 1161 | |
b6cc0a72 | 1162 | case ROUND_DIV_EXPR: |
e9a25f70 JL |
1163 | if (int2h == 0 && int2l == 1) |
1164 | { | |
1165 | low = int1l, hi = int1h; | |
6d716ca8 | 1166 | break; |
e9a25f70 JL |
1167 | } |
1168 | if (int1l == int2l && int1h == int2h | |
1169 | && ! (int1l == 0 && int1h == 0)) | |
1170 | { | |
1171 | low = 1, hi = 0; | |
63e7fe9b | 1172 | break; |
e9a25f70 | 1173 | } |
4c160717 | 1174 | overflow = div_and_round_double (code, uns, int1l, int1h, int2l, int2h, |
e9a25f70 JL |
1175 | &low, &hi, &garbagel, &garbageh); |
1176 | break; | |
63e7fe9b | 1177 | |
e9a25f70 JL |
1178 | case TRUNC_MOD_EXPR: |
1179 | case FLOOR_MOD_EXPR: case CEIL_MOD_EXPR: | |
1180 | /* This is a shortcut for a common special case. */ | |
05bccae2 | 1181 | if (int2h == 0 && (HOST_WIDE_INT) int2l > 0 |
e9a25f70 JL |
1182 | && ! TREE_CONSTANT_OVERFLOW (arg1) |
1183 | && ! TREE_CONSTANT_OVERFLOW (arg2) | |
05bccae2 | 1184 | && int1h == 0 && (HOST_WIDE_INT) int1l >= 0) |
e9a25f70 JL |
1185 | { |
1186 | if (code == CEIL_MOD_EXPR) | |
1187 | int1l += int2l - 1; | |
1188 | low = int1l % int2l, hi = 0; | |
63e7fe9b | 1189 | break; |
e9a25f70 | 1190 | } |
63e7fe9b | 1191 | |
30f7a378 | 1192 | /* ... fall through ... */ |
e9a25f70 | 1193 | |
b6cc0a72 | 1194 | case ROUND_MOD_EXPR: |
e9a25f70 JL |
1195 | overflow = div_and_round_double (code, uns, |
1196 | int1l, int1h, int2l, int2h, | |
1197 | &garbagel, &garbageh, &low, &hi); | |
1198 | break; | |
1199 | ||
1200 | case MIN_EXPR: | |
1201 | case MAX_EXPR: | |
1202 | if (uns) | |
d4b60170 RK |
1203 | low = (((unsigned HOST_WIDE_INT) int1h |
1204 | < (unsigned HOST_WIDE_INT) int2h) | |
1205 | || (((unsigned HOST_WIDE_INT) int1h | |
1206 | == (unsigned HOST_WIDE_INT) int2h) | |
05bccae2 | 1207 | && int1l < int2l)); |
380ff34a | 1208 | else |
05bccae2 RK |
1209 | low = (int1h < int2h |
1210 | || (int1h == int2h && int1l < int2l)); | |
d4b60170 | 1211 | |
e9a25f70 JL |
1212 | if (low == (code == MIN_EXPR)) |
1213 | low = int1l, hi = int1h; | |
1214 | else | |
1215 | low = int2l, hi = int2h; | |
1216 | break; | |
3dedc65a | 1217 | |
e9a25f70 JL |
1218 | default: |
1219 | abort (); | |
3dedc65a | 1220 | } |
e9a25f70 | 1221 | |
4c160717 RK |
1222 | /* If this is for a sizetype, can be represented as one (signed) |
1223 | HOST_WIDE_INT word, and doesn't overflow, use size_int since it caches | |
1224 | constants. */ | |
1225 | if (is_sizetype | |
1226 | && ((hi == 0 && (HOST_WIDE_INT) low >= 0) | |
1227 | || (hi == -1 && (HOST_WIDE_INT) low < 0)) | |
44475138 | 1228 | && overflow == 0 && ! TREE_OVERFLOW (arg1) && ! TREE_OVERFLOW (arg2)) |
4c160717 | 1229 | return size_int_type_wide (low, type); |
e9a25f70 JL |
1230 | else |
1231 | { | |
1232 | t = build_int_2 (low, hi); | |
1233 | TREE_TYPE (t) = TREE_TYPE (arg1); | |
1234 | } | |
1235 | ||
1236 | TREE_OVERFLOW (t) | |
4c160717 RK |
1237 | = ((notrunc |
1238 | ? (!uns || is_sizetype) && overflow | |
1239 | : (force_fit_type (t, (!uns || is_sizetype) && overflow) | |
1240 | && ! no_overflow)) | |
e9a25f70 JL |
1241 | | TREE_OVERFLOW (arg1) |
1242 | | TREE_OVERFLOW (arg2)); | |
d4b60170 | 1243 | |
e9a25f70 JL |
1244 | /* If we're doing a size calculation, unsigned arithmetic does overflow. |
1245 | So check if force_fit_type truncated the value. */ | |
4c160717 | 1246 | if (is_sizetype |
e9a25f70 JL |
1247 | && ! TREE_OVERFLOW (t) |
1248 | && (TREE_INT_CST_HIGH (t) != hi | |
1249 | || TREE_INT_CST_LOW (t) != low)) | |
1250 | TREE_OVERFLOW (t) = 1; | |
d4b60170 | 1251 | |
e9a25f70 JL |
1252 | TREE_CONSTANT_OVERFLOW (t) = (TREE_OVERFLOW (t) |
1253 | | TREE_CONSTANT_OVERFLOW (arg1) | |
1254 | | TREE_CONSTANT_OVERFLOW (arg2)); | |
1255 | return t; | |
1256 | } | |
1257 | ||
d4b60170 RK |
1258 | /* Combine two constants ARG1 and ARG2 under operation CODE to produce a new |
1259 | constant. We assume ARG1 and ARG2 have the same data type, or at least | |
1260 | are the same kind of constant and the same machine mode. | |
e9a25f70 JL |
1261 | |
1262 | If NOTRUNC is nonzero, do not truncate the result to fit the data type. */ | |
1263 | ||
1264 | static tree | |
fa8db1f7 | 1265 | const_binop (enum tree_code code, tree arg1, tree arg2, int notrunc) |
e9a25f70 | 1266 | { |
b6cc0a72 KH |
1267 | STRIP_NOPS (arg1); |
1268 | STRIP_NOPS (arg2); | |
e9a25f70 JL |
1269 | |
1270 | if (TREE_CODE (arg1) == INTEGER_CST) | |
4c160717 | 1271 | return int_const_binop (code, arg1, arg2, notrunc); |
e9a25f70 | 1272 | |
6d716ca8 RS |
1273 | if (TREE_CODE (arg1) == REAL_CST) |
1274 | { | |
3e4093b6 | 1275 | enum machine_mode mode; |
79c844cd RK |
1276 | REAL_VALUE_TYPE d1; |
1277 | REAL_VALUE_TYPE d2; | |
15e5ad76 | 1278 | REAL_VALUE_TYPE value; |
3e4093b6 | 1279 | tree t, type; |
6d716ca8 | 1280 | |
79c844cd RK |
1281 | d1 = TREE_REAL_CST (arg1); |
1282 | d2 = TREE_REAL_CST (arg2); | |
5f610074 | 1283 | |
3e4093b6 RS |
1284 | type = TREE_TYPE (arg1); |
1285 | mode = TYPE_MODE (type); | |
1286 | ||
1287 | /* Don't perform operation if we honor signaling NaNs and | |
1288 | either operand is a NaN. */ | |
1289 | if (HONOR_SNANS (mode) | |
1290 | && (REAL_VALUE_ISNAN (d1) || REAL_VALUE_ISNAN (d2))) | |
1291 | return NULL_TREE; | |
1292 | ||
1293 | /* Don't perform operation if it would raise a division | |
1294 | by zero exception. */ | |
1295 | if (code == RDIV_EXPR | |
1296 | && REAL_VALUES_EQUAL (d2, dconst0) | |
1297 | && (flag_trapping_math || ! MODE_HAS_INFINITIES (mode))) | |
1298 | return NULL_TREE; | |
1299 | ||
5f610074 RK |
1300 | /* If either operand is a NaN, just return it. Otherwise, set up |
1301 | for floating-point trap; we return an overflow. */ | |
1302 | if (REAL_VALUE_ISNAN (d1)) | |
1303 | return arg1; | |
1304 | else if (REAL_VALUE_ISNAN (d2)) | |
1305 | return arg2; | |
a4d3481d | 1306 | |
15e5ad76 | 1307 | REAL_ARITHMETIC (value, code, d1, d2); |
b6cc0a72 | 1308 | |
3e4093b6 | 1309 | t = build_real (type, real_value_truncate (mode, value)); |
649ff3b4 RK |
1310 | |
1311 | TREE_OVERFLOW (t) | |
15e5ad76 | 1312 | = (force_fit_type (t, 0) |
649ff3b4 RK |
1313 | | TREE_OVERFLOW (arg1) | TREE_OVERFLOW (arg2)); |
1314 | TREE_CONSTANT_OVERFLOW (t) | |
1315 | = TREE_OVERFLOW (t) | |
1316 | | TREE_CONSTANT_OVERFLOW (arg1) | |
1317 | | TREE_CONSTANT_OVERFLOW (arg2); | |
7c7b029d | 1318 | return t; |
6d716ca8 | 1319 | } |
6d716ca8 RS |
1320 | if (TREE_CODE (arg1) == COMPLEX_CST) |
1321 | { | |
b3694847 SS |
1322 | tree type = TREE_TYPE (arg1); |
1323 | tree r1 = TREE_REALPART (arg1); | |
1324 | tree i1 = TREE_IMAGPART (arg1); | |
1325 | tree r2 = TREE_REALPART (arg2); | |
1326 | tree i2 = TREE_IMAGPART (arg2); | |
1327 | tree t; | |
6d716ca8 RS |
1328 | |
1329 | switch (code) | |
1330 | { | |
1331 | case PLUS_EXPR: | |
214d5b84 RK |
1332 | t = build_complex (type, |
1333 | const_binop (PLUS_EXPR, r1, r2, notrunc), | |
91d33e36 | 1334 | const_binop (PLUS_EXPR, i1, i2, notrunc)); |
6d716ca8 RS |
1335 | break; |
1336 | ||
1337 | case MINUS_EXPR: | |
214d5b84 RK |
1338 | t = build_complex (type, |
1339 | const_binop (MINUS_EXPR, r1, r2, notrunc), | |
91d33e36 | 1340 | const_binop (MINUS_EXPR, i1, i2, notrunc)); |
6d716ca8 RS |
1341 | break; |
1342 | ||
1343 | case MULT_EXPR: | |
214d5b84 RK |
1344 | t = build_complex (type, |
1345 | const_binop (MINUS_EXPR, | |
91d33e36 RS |
1346 | const_binop (MULT_EXPR, |
1347 | r1, r2, notrunc), | |
1348 | const_binop (MULT_EXPR, | |
1349 | i1, i2, notrunc), | |
1350 | notrunc), | |
6d716ca8 | 1351 | const_binop (PLUS_EXPR, |
91d33e36 RS |
1352 | const_binop (MULT_EXPR, |
1353 | r1, i2, notrunc), | |
1354 | const_binop (MULT_EXPR, | |
1355 | i1, r2, notrunc), | |
1356 | notrunc)); | |
6d716ca8 RS |
1357 | break; |
1358 | ||
1359 | case RDIV_EXPR: | |
1360 | { | |
b3694847 | 1361 | tree magsquared |
6d716ca8 | 1362 | = const_binop (PLUS_EXPR, |
91d33e36 RS |
1363 | const_binop (MULT_EXPR, r2, r2, notrunc), |
1364 | const_binop (MULT_EXPR, i2, i2, notrunc), | |
1365 | notrunc); | |
58633be8 | 1366 | |
214d5b84 RK |
1367 | t = build_complex (type, |
1368 | const_binop | |
1369 | (INTEGRAL_TYPE_P (TREE_TYPE (r1)) | |
1370 | ? TRUNC_DIV_EXPR : RDIV_EXPR, | |
1371 | const_binop (PLUS_EXPR, | |
1372 | const_binop (MULT_EXPR, r1, r2, | |
1373 | notrunc), | |
1374 | const_binop (MULT_EXPR, i1, i2, | |
1375 | notrunc), | |
1376 | notrunc), | |
1377 | magsquared, notrunc), | |
1378 | const_binop | |
1379 | (INTEGRAL_TYPE_P (TREE_TYPE (r1)) | |
1380 | ? TRUNC_DIV_EXPR : RDIV_EXPR, | |
1381 | const_binop (MINUS_EXPR, | |
1382 | const_binop (MULT_EXPR, i1, r2, | |
1383 | notrunc), | |
1384 | const_binop (MULT_EXPR, r1, i2, | |
1385 | notrunc), | |
1386 | notrunc), | |
1387 | magsquared, notrunc)); | |
6d716ca8 RS |
1388 | } |
1389 | break; | |
1390 | ||
1391 | default: | |
1392 | abort (); | |
1393 | } | |
6d716ca8 RS |
1394 | return t; |
1395 | } | |
1396 | return 0; | |
1397 | } | |
4c160717 RK |
1398 | |
1399 | /* These are the hash table functions for the hash table of INTEGER_CST | |
1400 | nodes of a sizetype. */ | |
1401 | ||
1402 | /* Return the hash code code X, an INTEGER_CST. */ | |
1403 | ||
1404 | static hashval_t | |
fa8db1f7 | 1405 | size_htab_hash (const void *x) |
4c160717 RK |
1406 | { |
1407 | tree t = (tree) x; | |
1408 | ||
1409 | return (TREE_INT_CST_HIGH (t) ^ TREE_INT_CST_LOW (t) | |
7bdfd72e | 1410 | ^ htab_hash_pointer (TREE_TYPE (t)) |
4c160717 RK |
1411 | ^ (TREE_OVERFLOW (t) << 20)); |
1412 | } | |
1413 | ||
cc2902df | 1414 | /* Return nonzero if the value represented by *X (an INTEGER_CST tree node) |
4c160717 RK |
1415 | is the same as that given by *Y, which is the same. */ |
1416 | ||
1417 | static int | |
fa8db1f7 | 1418 | size_htab_eq (const void *x, const void *y) |
4c160717 RK |
1419 | { |
1420 | tree xt = (tree) x; | |
1421 | tree yt = (tree) y; | |
1422 | ||
1423 | return (TREE_INT_CST_HIGH (xt) == TREE_INT_CST_HIGH (yt) | |
1424 | && TREE_INT_CST_LOW (xt) == TREE_INT_CST_LOW (yt) | |
1425 | && TREE_TYPE (xt) == TREE_TYPE (yt) | |
1426 | && TREE_OVERFLOW (xt) == TREE_OVERFLOW (yt)); | |
1427 | } | |
6d716ca8 | 1428 | \f |
06ceef4e | 1429 | /* Return an INTEGER_CST with value whose low-order HOST_BITS_PER_WIDE_INT |
fed3cef0 | 1430 | bits are given by NUMBER and of the sizetype represented by KIND. */ |
d4b60170 | 1431 | |
fed3cef0 | 1432 | tree |
fa8db1f7 | 1433 | size_int_wide (HOST_WIDE_INT number, enum size_type_kind kind) |
fed3cef0 RK |
1434 | { |
1435 | return size_int_type_wide (number, sizetype_tab[(int) kind]); | |
1436 | } | |
1437 | ||
1438 | /* Likewise, but the desired type is specified explicitly. */ | |
6d716ca8 | 1439 | |
e2500fed GK |
1440 | static GTY (()) tree new_const; |
1441 | static GTY ((if_marked ("ggc_marked_p"), param_is (union tree_node))) | |
1442 | htab_t size_htab; | |
1443 | ||
6d716ca8 | 1444 | tree |
fa8db1f7 | 1445 | size_int_type_wide (HOST_WIDE_INT number, tree type) |
6d716ca8 | 1446 | { |
fad205ff | 1447 | void **slot; |
b6cc0a72 | 1448 | |
4c160717 | 1449 | if (size_htab == 0) |
6d716ca8 | 1450 | { |
17211ab5 | 1451 | size_htab = htab_create_ggc (1024, size_htab_hash, size_htab_eq, NULL); |
4c160717 | 1452 | new_const = make_node (INTEGER_CST); |
d4b60170 RK |
1453 | } |
1454 | ||
4c160717 RK |
1455 | /* Adjust NEW_CONST to be the constant we want. If it's already in the |
1456 | hash table, we return the value from the hash table. Otherwise, we | |
1457 | place that in the hash table and make a new node for the next time. */ | |
1458 | TREE_INT_CST_LOW (new_const) = number; | |
1459 | TREE_INT_CST_HIGH (new_const) = number < 0 ? -1 : 0; | |
1460 | TREE_TYPE (new_const) = type; | |
1461 | TREE_OVERFLOW (new_const) = TREE_CONSTANT_OVERFLOW (new_const) | |
1462 | = force_fit_type (new_const, 0); | |
1463 | ||
1464 | slot = htab_find_slot (size_htab, new_const, INSERT); | |
1465 | if (*slot == 0) | |
d4b60170 | 1466 | { |
4c160717 | 1467 | tree t = new_const; |
d4b60170 | 1468 | |
fad205ff | 1469 | *slot = new_const; |
4c160717 | 1470 | new_const = make_node (INTEGER_CST); |
d4b60170 | 1471 | return t; |
6d716ca8 | 1472 | } |
4c160717 RK |
1473 | else |
1474 | return (tree) *slot; | |
6d716ca8 RS |
1475 | } |
1476 | ||
fed3cef0 RK |
1477 | /* Combine operands OP1 and OP2 with arithmetic operation CODE. CODE |
1478 | is a tree code. The type of the result is taken from the operands. | |
1479 | Both must be the same type integer type and it must be a size type. | |
6d716ca8 RS |
1480 | If the operands are constant, so is the result. */ |
1481 | ||
1482 | tree | |
fa8db1f7 | 1483 | size_binop (enum tree_code code, tree arg0, tree arg1) |
6d716ca8 | 1484 | { |
fed3cef0 RK |
1485 | tree type = TREE_TYPE (arg0); |
1486 | ||
21318741 RK |
1487 | if (TREE_CODE (type) != INTEGER_TYPE || ! TYPE_IS_SIZETYPE (type) |
1488 | || type != TREE_TYPE (arg1)) | |
fed3cef0 RK |
1489 | abort (); |
1490 | ||
6d716ca8 RS |
1491 | /* Handle the special case of two integer constants faster. */ |
1492 | if (TREE_CODE (arg0) == INTEGER_CST && TREE_CODE (arg1) == INTEGER_CST) | |
1493 | { | |
1494 | /* And some specific cases even faster than that. */ | |
9898deac | 1495 | if (code == PLUS_EXPR && integer_zerop (arg0)) |
6d716ca8 | 1496 | return arg1; |
9898deac RK |
1497 | else if ((code == MINUS_EXPR || code == PLUS_EXPR) |
1498 | && integer_zerop (arg1)) | |
6d716ca8 | 1499 | return arg0; |
9898deac | 1500 | else if (code == MULT_EXPR && integer_onep (arg0)) |
6d716ca8 | 1501 | return arg1; |
9898deac | 1502 | |
6d716ca8 | 1503 | /* Handle general case of two integer constants. */ |
4c160717 | 1504 | return int_const_binop (code, arg0, arg1, 0); |
6d716ca8 RS |
1505 | } |
1506 | ||
1507 | if (arg0 == error_mark_node || arg1 == error_mark_node) | |
1508 | return error_mark_node; | |
1509 | ||
fed3cef0 | 1510 | return fold (build (code, type, arg0, arg1)); |
6d716ca8 | 1511 | } |
697073d9 | 1512 | |
fed3cef0 RK |
1513 | /* Given two values, either both of sizetype or both of bitsizetype, |
1514 | compute the difference between the two values. Return the value | |
1515 | in signed type corresponding to the type of the operands. */ | |
697073d9 JM |
1516 | |
1517 | tree | |
fa8db1f7 | 1518 | size_diffop (tree arg0, tree arg1) |
697073d9 | 1519 | { |
fed3cef0 RK |
1520 | tree type = TREE_TYPE (arg0); |
1521 | tree ctype; | |
697073d9 | 1522 | |
21318741 RK |
1523 | if (TREE_CODE (type) != INTEGER_TYPE || ! TYPE_IS_SIZETYPE (type) |
1524 | || type != TREE_TYPE (arg1)) | |
fed3cef0 | 1525 | abort (); |
697073d9 | 1526 | |
fed3cef0 RK |
1527 | /* If the type is already signed, just do the simple thing. */ |
1528 | if (! TREE_UNSIGNED (type)) | |
1529 | return size_binop (MINUS_EXPR, arg0, arg1); | |
1530 | ||
1531 | ctype = (type == bitsizetype || type == ubitsizetype | |
1532 | ? sbitsizetype : ssizetype); | |
1533 | ||
1534 | /* If either operand is not a constant, do the conversions to the signed | |
1535 | type and subtract. The hardware will do the right thing with any | |
1536 | overflow in the subtraction. */ | |
1537 | if (TREE_CODE (arg0) != INTEGER_CST || TREE_CODE (arg1) != INTEGER_CST) | |
1538 | return size_binop (MINUS_EXPR, convert (ctype, arg0), | |
1539 | convert (ctype, arg1)); | |
1540 | ||
1541 | /* If ARG0 is larger than ARG1, subtract and return the result in CTYPE. | |
1542 | Otherwise, subtract the other way, convert to CTYPE (we know that can't | |
1543 | overflow) and negate (which can't either). Special-case a result | |
1544 | of zero while we're here. */ | |
1545 | if (tree_int_cst_equal (arg0, arg1)) | |
1546 | return convert (ctype, integer_zero_node); | |
1547 | else if (tree_int_cst_lt (arg1, arg0)) | |
1548 | return convert (ctype, size_binop (MINUS_EXPR, arg0, arg1)); | |
1549 | else | |
1550 | return size_binop (MINUS_EXPR, convert (ctype, integer_zero_node), | |
1551 | convert (ctype, size_binop (MINUS_EXPR, arg1, arg0))); | |
697073d9 | 1552 | } |
6d716ca8 | 1553 | \f |
a4d3481d | 1554 | |
6d716ca8 RS |
1555 | /* Given T, a tree representing type conversion of ARG1, a constant, |
1556 | return a constant tree representing the result of conversion. */ | |
1557 | ||
1558 | static tree | |
fa8db1f7 | 1559 | fold_convert (tree t, tree arg1) |
6d716ca8 | 1560 | { |
b3694847 | 1561 | tree type = TREE_TYPE (t); |
649ff3b4 | 1562 | int overflow = 0; |
6d716ca8 | 1563 | |
e5e809f4 | 1564 | if (POINTER_TYPE_P (type) || INTEGRAL_TYPE_P (type)) |
6d716ca8 RS |
1565 | { |
1566 | if (TREE_CODE (arg1) == INTEGER_CST) | |
1567 | { | |
e3374525 RK |
1568 | /* If we would build a constant wider than GCC supports, |
1569 | leave the conversion unfolded. */ | |
1570 | if (TYPE_PRECISION (type) > 2 * HOST_BITS_PER_WIDE_INT) | |
1571 | return t; | |
1572 | ||
fed3cef0 RK |
1573 | /* If we are trying to make a sizetype for a small integer, use |
1574 | size_int to pick up cached types to reduce duplicate nodes. */ | |
55560b9d | 1575 | if (TREE_CODE (type) == INTEGER_TYPE && TYPE_IS_SIZETYPE (type) |
ac50176d | 1576 | && !TREE_CONSTANT_OVERFLOW (arg1) |
770ae6cc | 1577 | && compare_tree_int (arg1, 10000) < 0) |
fed3cef0 RK |
1578 | return size_int_type_wide (TREE_INT_CST_LOW (arg1), type); |
1579 | ||
6d716ca8 RS |
1580 | /* Given an integer constant, make new constant with new type, |
1581 | appropriately sign-extended or truncated. */ | |
1582 | t = build_int_2 (TREE_INT_CST_LOW (arg1), | |
1583 | TREE_INT_CST_HIGH (arg1)); | |
1584 | TREE_TYPE (t) = type; | |
e0f776fb | 1585 | /* Indicate an overflow if (1) ARG1 already overflowed, |
dc3907c5 PE |
1586 | or (2) force_fit_type indicates an overflow. |
1587 | Tell force_fit_type that an overflow has already occurred | |
b472527b JL |
1588 | if ARG1 is a too-large unsigned value and T is signed. |
1589 | But don't indicate an overflow if converting a pointer. */ | |
dc3907c5 | 1590 | TREE_OVERFLOW (t) |
e5e809f4 JL |
1591 | = ((force_fit_type (t, |
1592 | (TREE_INT_CST_HIGH (arg1) < 0 | |
4f242db3 | 1593 | && (TREE_UNSIGNED (type) |
e5e809f4 JL |
1594 | < TREE_UNSIGNED (TREE_TYPE (arg1))))) |
1595 | && ! POINTER_TYPE_P (TREE_TYPE (arg1))) | |
1596 | || TREE_OVERFLOW (arg1)); | |
dc3907c5 PE |
1597 | TREE_CONSTANT_OVERFLOW (t) |
1598 | = TREE_OVERFLOW (t) | TREE_CONSTANT_OVERFLOW (arg1); | |
6d716ca8 | 1599 | } |
6d716ca8 RS |
1600 | else if (TREE_CODE (arg1) == REAL_CST) |
1601 | { | |
4b8a0062 RK |
1602 | /* Don't initialize these, use assignments. |
1603 | Initialized local aggregates don't work on old compilers. */ | |
1604 | REAL_VALUE_TYPE x; | |
1605 | REAL_VALUE_TYPE l; | |
1606 | REAL_VALUE_TYPE u; | |
7cb6a121 | 1607 | tree type1 = TREE_TYPE (arg1); |
e1ee5cdc | 1608 | int no_upper_bound; |
4b8a0062 RK |
1609 | |
1610 | x = TREE_REAL_CST (arg1); | |
7cb6a121 | 1611 | l = real_value_from_int_cst (type1, TYPE_MIN_VALUE (type)); |
e1ee5cdc RH |
1612 | |
1613 | no_upper_bound = (TYPE_MAX_VALUE (type) == NULL); | |
1614 | if (!no_upper_bound) | |
1615 | u = real_value_from_int_cst (type1, TYPE_MAX_VALUE (type)); | |
1616 | ||
4b3d5ea0 RS |
1617 | /* See if X will be in range after truncation towards 0. |
1618 | To compensate for truncation, move the bounds away from 0, | |
1619 | but reject if X exactly equals the adjusted bounds. */ | |
4b3d5ea0 | 1620 | REAL_ARITHMETIC (l, MINUS_EXPR, l, dconst1); |
e1ee5cdc RH |
1621 | if (!no_upper_bound) |
1622 | REAL_ARITHMETIC (u, PLUS_EXPR, u, dconst1); | |
5f610074 RK |
1623 | /* If X is a NaN, use zero instead and show we have an overflow. |
1624 | Otherwise, range check. */ | |
1625 | if (REAL_VALUE_ISNAN (x)) | |
1626 | overflow = 1, x = dconst0; | |
e1ee5cdc RH |
1627 | else if (! (REAL_VALUES_LESS (l, x) |
1628 | && !no_upper_bound | |
1629 | && REAL_VALUES_LESS (x, u))) | |
649ff3b4 RK |
1630 | overflow = 1; |
1631 | ||
6d716ca8 | 1632 | { |
906c4e36 | 1633 | HOST_WIDE_INT low, high; |
5f610074 | 1634 | REAL_VALUE_TO_INT (&low, &high, x); |
6d716ca8 RS |
1635 | t = build_int_2 (low, high); |
1636 | } | |
6d716ca8 | 1637 | TREE_TYPE (t) = type; |
649ff3b4 RK |
1638 | TREE_OVERFLOW (t) |
1639 | = TREE_OVERFLOW (arg1) | force_fit_type (t, overflow); | |
1640 | TREE_CONSTANT_OVERFLOW (t) | |
1641 | = TREE_OVERFLOW (t) | TREE_CONSTANT_OVERFLOW (arg1); | |
6d716ca8 | 1642 | } |
6d716ca8 RS |
1643 | TREE_TYPE (t) = type; |
1644 | } | |
1645 | else if (TREE_CODE (type) == REAL_TYPE) | |
1646 | { | |
6d716ca8 RS |
1647 | if (TREE_CODE (arg1) == INTEGER_CST) |
1648 | return build_real_from_int_cst (type, arg1); | |
6d716ca8 | 1649 | if (TREE_CODE (arg1) == REAL_CST) |
7c7b029d | 1650 | { |
5f610074 | 1651 | if (REAL_VALUE_ISNAN (TREE_REAL_CST (arg1))) |
a377ff85 | 1652 | { |
0797e472 TT |
1653 | /* We make a copy of ARG1 so that we don't modify an |
1654 | existing constant tree. */ | |
1655 | t = copy_node (arg1); | |
1656 | TREE_TYPE (t) = type; | |
a377ff85 RK |
1657 | return t; |
1658 | } | |
a4d3481d | 1659 | |
15e5ad76 ZW |
1660 | t = build_real (type, |
1661 | real_value_truncate (TYPE_MODE (type), | |
1662 | TREE_REAL_CST (arg1))); | |
649ff3b4 | 1663 | |
649ff3b4 | 1664 | TREE_OVERFLOW (t) |
15e5ad76 | 1665 | = TREE_OVERFLOW (arg1) | force_fit_type (t, 0); |
649ff3b4 RK |
1666 | TREE_CONSTANT_OVERFLOW (t) |
1667 | = TREE_OVERFLOW (t) | TREE_CONSTANT_OVERFLOW (arg1); | |
7c7b029d RS |
1668 | return t; |
1669 | } | |
6d716ca8 RS |
1670 | } |
1671 | TREE_CONSTANT (t) = 1; | |
1672 | return t; | |
1673 | } | |
1674 | \f | |
ff59bfe6 | 1675 | /* Return an expr equal to X but certainly not valid as an lvalue. */ |
6d716ca8 RS |
1676 | |
1677 | tree | |
fa8db1f7 | 1678 | non_lvalue (tree x) |
6d716ca8 RS |
1679 | { |
1680 | tree result; | |
1681 | ||
1682 | /* These things are certainly not lvalues. */ | |
1683 | if (TREE_CODE (x) == NON_LVALUE_EXPR | |
1684 | || TREE_CODE (x) == INTEGER_CST | |
1685 | || TREE_CODE (x) == REAL_CST | |
1686 | || TREE_CODE (x) == STRING_CST | |
1687 | || TREE_CODE (x) == ADDR_EXPR) | |
ff59bfe6 | 1688 | return x; |
6d716ca8 RS |
1689 | |
1690 | result = build1 (NON_LVALUE_EXPR, TREE_TYPE (x), x); | |
1691 | TREE_CONSTANT (result) = TREE_CONSTANT (x); | |
1692 | return result; | |
1693 | } | |
a5e9b124 | 1694 | |
e9866da3 JM |
1695 | /* Nonzero means lvalues are limited to those valid in pedantic ANSI C. |
1696 | Zero means allow extended lvalues. */ | |
1697 | ||
1698 | int pedantic_lvalues; | |
1699 | ||
a5e9b124 JW |
1700 | /* When pedantic, return an expr equal to X but certainly not valid as a |
1701 | pedantic lvalue. Otherwise, return X. */ | |
1702 | ||
1703 | tree | |
fa8db1f7 | 1704 | pedantic_non_lvalue (tree x) |
a5e9b124 | 1705 | { |
e9866da3 | 1706 | if (pedantic_lvalues) |
a5e9b124 JW |
1707 | return non_lvalue (x); |
1708 | else | |
1709 | return x; | |
1710 | } | |
c05a9b68 RS |
1711 | \f |
1712 | /* Given a tree comparison code, return the code that is the logical inverse | |
1713 | of the given code. It is not safe to do this for floating-point | |
1714 | comparisons, except for NE_EXPR and EQ_EXPR. */ | |
6d716ca8 | 1715 | |
c05a9b68 | 1716 | static enum tree_code |
fa8db1f7 | 1717 | invert_tree_comparison (enum tree_code code) |
c05a9b68 RS |
1718 | { |
1719 | switch (code) | |
1720 | { | |
1721 | case EQ_EXPR: | |
1722 | return NE_EXPR; | |
1723 | case NE_EXPR: | |
1724 | return EQ_EXPR; | |
1725 | case GT_EXPR: | |
1726 | return LE_EXPR; | |
1727 | case GE_EXPR: | |
1728 | return LT_EXPR; | |
1729 | case LT_EXPR: | |
1730 | return GE_EXPR; | |
1731 | case LE_EXPR: | |
1732 | return GT_EXPR; | |
1733 | default: | |
1734 | abort (); | |
1735 | } | |
1736 | } | |
1737 | ||
1738 | /* Similar, but return the comparison that results if the operands are | |
1739 | swapped. This is safe for floating-point. */ | |
1740 | ||
1741 | static enum tree_code | |
fa8db1f7 | 1742 | swap_tree_comparison (enum tree_code code) |
c05a9b68 RS |
1743 | { |
1744 | switch (code) | |
1745 | { | |
1746 | case EQ_EXPR: | |
1747 | case NE_EXPR: | |
1748 | return code; | |
1749 | case GT_EXPR: | |
1750 | return LT_EXPR; | |
1751 | case GE_EXPR: | |
1752 | return LE_EXPR; | |
1753 | case LT_EXPR: | |
1754 | return GT_EXPR; | |
1755 | case LE_EXPR: | |
1756 | return GE_EXPR; | |
1757 | default: | |
1758 | abort (); | |
1759 | } | |
1760 | } | |
61f275ff | 1761 | |
8dcb27ed RS |
1762 | |
1763 | /* Convert a comparison tree code from an enum tree_code representation | |
1764 | into a compcode bit-based encoding. This function is the inverse of | |
1765 | compcode_to_comparison. */ | |
1766 | ||
1767 | static int | |
fa8db1f7 | 1768 | comparison_to_compcode (enum tree_code code) |
8dcb27ed RS |
1769 | { |
1770 | switch (code) | |
1771 | { | |
1772 | case LT_EXPR: | |
1773 | return COMPCODE_LT; | |
1774 | case EQ_EXPR: | |
1775 | return COMPCODE_EQ; | |
1776 | case LE_EXPR: | |
1777 | return COMPCODE_LE; | |
1778 | case GT_EXPR: | |
1779 | return COMPCODE_GT; | |
1780 | case NE_EXPR: | |
1781 | return COMPCODE_NE; | |
1782 | case GE_EXPR: | |
1783 | return COMPCODE_GE; | |
1784 | default: | |
1785 | abort (); | |
1786 | } | |
1787 | } | |
1788 | ||
1789 | /* Convert a compcode bit-based encoding of a comparison operator back | |
1790 | to GCC's enum tree_code representation. This function is the | |
1791 | inverse of comparison_to_compcode. */ | |
1792 | ||
1793 | static enum tree_code | |
fa8db1f7 | 1794 | compcode_to_comparison (int code) |
8dcb27ed RS |
1795 | { |
1796 | switch (code) | |
1797 | { | |
1798 | case COMPCODE_LT: | |
1799 | return LT_EXPR; | |
1800 | case COMPCODE_EQ: | |
1801 | return EQ_EXPR; | |
1802 | case COMPCODE_LE: | |
1803 | return LE_EXPR; | |
1804 | case COMPCODE_GT: | |
1805 | return GT_EXPR; | |
1806 | case COMPCODE_NE: | |
1807 | return NE_EXPR; | |
1808 | case COMPCODE_GE: | |
1809 | return GE_EXPR; | |
1810 | default: | |
1811 | abort (); | |
1812 | } | |
1813 | } | |
1814 | ||
61f275ff RK |
1815 | /* Return nonzero if CODE is a tree code that represents a truth value. */ |
1816 | ||
1817 | static int | |
fa8db1f7 | 1818 | truth_value_p (enum tree_code code) |
61f275ff RK |
1819 | { |
1820 | return (TREE_CODE_CLASS (code) == '<' | |
1821 | || code == TRUTH_AND_EXPR || code == TRUTH_ANDIF_EXPR | |
1822 | || code == TRUTH_OR_EXPR || code == TRUTH_ORIF_EXPR | |
1823 | || code == TRUTH_XOR_EXPR || code == TRUTH_NOT_EXPR); | |
1824 | } | |
c05a9b68 | 1825 | \f |
fae111c1 RS |
1826 | /* Return nonzero if two operands (typically of the same tree node) |
1827 | are necessarily equal. If either argument has side-effects this | |
1828 | function returns zero. | |
1829 | ||
cc2902df | 1830 | If ONLY_CONST is nonzero, only return nonzero for constants. |
6a1746af RS |
1831 | This function tests whether the operands are indistinguishable; |
1832 | it does not test whether they are equal using C's == operation. | |
1833 | The distinction is important for IEEE floating point, because | |
1834 | (1) -0.0 and 0.0 are distinguishable, but -0.0==0.0, and | |
fae111c1 RS |
1835 | (2) two NaNs may be indistinguishable, but NaN!=NaN. |
1836 | ||
1837 | If ONLY_CONST is zero, a VAR_DECL is considered equal to itself | |
1838 | even though it may hold multiple values during a function. | |
1839 | This is because a GCC tree node guarantees that nothing else is | |
1840 | executed between the evaluation of its "operands" (which may often | |
1841 | be evaluated in arbitrary order). Hence if the operands themselves | |
1842 | don't side-effect, the VAR_DECLs, PARM_DECLs etc... must hold the | |
1843 | same value in each operand/subexpression. Hence a zero value for | |
1844 | ONLY_CONST assumes isochronic (or instantaneous) tree equivalence. | |
1845 | If comparing arbitrary expression trees, such as from different | |
83a00410 | 1846 | statements, ONLY_CONST must usually be nonzero. */ |
6d716ca8 RS |
1847 | |
1848 | int | |
fa8db1f7 | 1849 | operand_equal_p (tree arg0, tree arg1, int only_const) |
6d716ca8 | 1850 | { |
2f503025 JM |
1851 | tree fndecl; |
1852 | ||
6d716ca8 RS |
1853 | /* If both types don't have the same signedness, then we can't consider |
1854 | them equal. We must check this before the STRIP_NOPS calls | |
1855 | because they may change the signedness of the arguments. */ | |
1856 | if (TREE_UNSIGNED (TREE_TYPE (arg0)) != TREE_UNSIGNED (TREE_TYPE (arg1))) | |
1857 | return 0; | |
1858 | ||
1859 | STRIP_NOPS (arg0); | |
1860 | STRIP_NOPS (arg1); | |
1861 | ||
c7cfe938 RK |
1862 | if (TREE_CODE (arg0) != TREE_CODE (arg1) |
1863 | /* This is needed for conversions and for COMPONENT_REF. | |
1864 | Might as well play it safe and always test this. */ | |
e89a9554 ZW |
1865 | || TREE_CODE (TREE_TYPE (arg0)) == ERROR_MARK |
1866 | || TREE_CODE (TREE_TYPE (arg1)) == ERROR_MARK | |
c7cfe938 | 1867 | || TYPE_MODE (TREE_TYPE (arg0)) != TYPE_MODE (TREE_TYPE (arg1))) |
6d716ca8 RS |
1868 | return 0; |
1869 | ||
c7cfe938 RK |
1870 | /* If ARG0 and ARG1 are the same SAVE_EXPR, they are necessarily equal. |
1871 | We don't care about side effects in that case because the SAVE_EXPR | |
1872 | takes care of that for us. In all other cases, two expressions are | |
1873 | equal if they have no side effects. If we have two identical | |
1874 | expressions with side effects that should be treated the same due | |
1875 | to the only side effects being identical SAVE_EXPR's, that will | |
1876 | be detected in the recursive calls below. */ | |
1877 | if (arg0 == arg1 && ! only_const | |
1878 | && (TREE_CODE (arg0) == SAVE_EXPR | |
1879 | || (! TREE_SIDE_EFFECTS (arg0) && ! TREE_SIDE_EFFECTS (arg1)))) | |
6d716ca8 RS |
1880 | return 1; |
1881 | ||
c7cfe938 RK |
1882 | /* Next handle constant cases, those for which we can return 1 even |
1883 | if ONLY_CONST is set. */ | |
1884 | if (TREE_CONSTANT (arg0) && TREE_CONSTANT (arg1)) | |
1885 | switch (TREE_CODE (arg0)) | |
1886 | { | |
1887 | case INTEGER_CST: | |
3c9b0091 RK |
1888 | return (! TREE_CONSTANT_OVERFLOW (arg0) |
1889 | && ! TREE_CONSTANT_OVERFLOW (arg1) | |
05bccae2 | 1890 | && tree_int_cst_equal (arg0, arg1)); |
c7cfe938 RK |
1891 | |
1892 | case REAL_CST: | |
3c9b0091 RK |
1893 | return (! TREE_CONSTANT_OVERFLOW (arg0) |
1894 | && ! TREE_CONSTANT_OVERFLOW (arg1) | |
41c9120b PE |
1895 | && REAL_VALUES_IDENTICAL (TREE_REAL_CST (arg0), |
1896 | TREE_REAL_CST (arg1))); | |
c7cfe938 | 1897 | |
69ef87e2 AH |
1898 | case VECTOR_CST: |
1899 | { | |
1900 | tree v1, v2; | |
1901 | ||
1902 | if (TREE_CONSTANT_OVERFLOW (arg0) | |
1903 | || TREE_CONSTANT_OVERFLOW (arg1)) | |
1904 | return 0; | |
1905 | ||
1906 | v1 = TREE_VECTOR_CST_ELTS (arg0); | |
1907 | v2 = TREE_VECTOR_CST_ELTS (arg1); | |
1908 | while (v1 && v2) | |
1909 | { | |
1910 | if (!operand_equal_p (v1, v2, only_const)) | |
1911 | return 0; | |
1912 | v1 = TREE_CHAIN (v1); | |
1913 | v2 = TREE_CHAIN (v2); | |
1914 | } | |
1915 | ||
1916 | return 1; | |
1917 | } | |
1918 | ||
c7cfe938 RK |
1919 | case COMPLEX_CST: |
1920 | return (operand_equal_p (TREE_REALPART (arg0), TREE_REALPART (arg1), | |
1921 | only_const) | |
1922 | && operand_equal_p (TREE_IMAGPART (arg0), TREE_IMAGPART (arg1), | |
1923 | only_const)); | |
1924 | ||
1925 | case STRING_CST: | |
1926 | return (TREE_STRING_LENGTH (arg0) == TREE_STRING_LENGTH (arg1) | |
71145810 | 1927 | && ! memcmp (TREE_STRING_POINTER (arg0), |
c7cfe938 RK |
1928 | TREE_STRING_POINTER (arg1), |
1929 | TREE_STRING_LENGTH (arg0))); | |
1930 | ||
1931 | case ADDR_EXPR: | |
1932 | return operand_equal_p (TREE_OPERAND (arg0, 0), TREE_OPERAND (arg1, 0), | |
1933 | 0); | |
e9a25f70 JL |
1934 | default: |
1935 | break; | |
c7cfe938 | 1936 | } |
6d716ca8 RS |
1937 | |
1938 | if (only_const) | |
1939 | return 0; | |
1940 | ||
6d716ca8 RS |
1941 | switch (TREE_CODE_CLASS (TREE_CODE (arg0))) |
1942 | { | |
1943 | case '1': | |
1944 | /* Two conversions are equal only if signedness and modes match. */ | |
1945 | if ((TREE_CODE (arg0) == NOP_EXPR || TREE_CODE (arg0) == CONVERT_EXPR) | |
1946 | && (TREE_UNSIGNED (TREE_TYPE (arg0)) | |
1947 | != TREE_UNSIGNED (TREE_TYPE (arg1)))) | |
1948 | return 0; | |
1949 | ||
1950 | return operand_equal_p (TREE_OPERAND (arg0, 0), | |
1951 | TREE_OPERAND (arg1, 0), 0); | |
1952 | ||
1953 | case '<': | |
1954 | case '2': | |
c7cfe938 RK |
1955 | if (operand_equal_p (TREE_OPERAND (arg0, 0), TREE_OPERAND (arg1, 0), 0) |
1956 | && operand_equal_p (TREE_OPERAND (arg0, 1), TREE_OPERAND (arg1, 1), | |
1957 | 0)) | |
1958 | return 1; | |
1959 | ||
1960 | /* For commutative ops, allow the other order. */ | |
1961 | return ((TREE_CODE (arg0) == PLUS_EXPR || TREE_CODE (arg0) == MULT_EXPR | |
1962 | || TREE_CODE (arg0) == MIN_EXPR || TREE_CODE (arg0) == MAX_EXPR | |
1963 | || TREE_CODE (arg0) == BIT_IOR_EXPR | |
1964 | || TREE_CODE (arg0) == BIT_XOR_EXPR | |
1965 | || TREE_CODE (arg0) == BIT_AND_EXPR | |
1966 | || TREE_CODE (arg0) == NE_EXPR || TREE_CODE (arg0) == EQ_EXPR) | |
1967 | && operand_equal_p (TREE_OPERAND (arg0, 0), | |
1968 | TREE_OPERAND (arg1, 1), 0) | |
6d716ca8 | 1969 | && operand_equal_p (TREE_OPERAND (arg0, 1), |
c7cfe938 | 1970 | TREE_OPERAND (arg1, 0), 0)); |
6d716ca8 RS |
1971 | |
1972 | case 'r': | |
21c43754 RS |
1973 | /* If either of the pointer (or reference) expressions we are |
1974 | dereferencing contain a side effect, these cannot be equal. */ | |
05ca5990 GRK |
1975 | if (TREE_SIDE_EFFECTS (arg0) |
1976 | || TREE_SIDE_EFFECTS (arg1)) | |
1977 | return 0; | |
1978 | ||
6d716ca8 RS |
1979 | switch (TREE_CODE (arg0)) |
1980 | { | |
1981 | case INDIRECT_REF: | |
1982 | return operand_equal_p (TREE_OPERAND (arg0, 0), | |
1983 | TREE_OPERAND (arg1, 0), 0); | |
1984 | ||
1985 | case COMPONENT_REF: | |
1986 | case ARRAY_REF: | |
b4e3fabb | 1987 | case ARRAY_RANGE_REF: |
6d716ca8 RS |
1988 | return (operand_equal_p (TREE_OPERAND (arg0, 0), |
1989 | TREE_OPERAND (arg1, 0), 0) | |
1990 | && operand_equal_p (TREE_OPERAND (arg0, 1), | |
1991 | TREE_OPERAND (arg1, 1), 0)); | |
1992 | ||
1993 | case BIT_FIELD_REF: | |
1994 | return (operand_equal_p (TREE_OPERAND (arg0, 0), | |
1995 | TREE_OPERAND (arg1, 0), 0) | |
1996 | && operand_equal_p (TREE_OPERAND (arg0, 1), | |
1997 | TREE_OPERAND (arg1, 1), 0) | |
1998 | && operand_equal_p (TREE_OPERAND (arg0, 2), | |
1999 | TREE_OPERAND (arg1, 2), 0)); | |
e9a25f70 JL |
2000 | default: |
2001 | return 0; | |
6d716ca8 | 2002 | } |
45f97e2e RH |
2003 | |
2004 | case 'e': | |
1bfedcc8 JM |
2005 | switch (TREE_CODE (arg0)) |
2006 | { | |
2007 | case ADDR_EXPR: | |
2008 | case TRUTH_NOT_EXPR: | |
2009 | return operand_equal_p (TREE_OPERAND (arg0, 0), | |
2010 | TREE_OPERAND (arg1, 0), 0); | |
2011 | ||
2012 | case RTL_EXPR: | |
2013 | return rtx_equal_p (RTL_EXPR_RTL (arg0), RTL_EXPR_RTL (arg1)); | |
2014 | ||
21c43754 RS |
2015 | case CALL_EXPR: |
2016 | /* If the CALL_EXPRs call different functions, then they | |
2017 | clearly can not be equal. */ | |
2018 | if (! operand_equal_p (TREE_OPERAND (arg0, 0), | |
2019 | TREE_OPERAND (arg1, 0), 0)) | |
2020 | return 0; | |
2021 | ||
2022 | /* Only consider const functions equivalent. */ | |
2f503025 JM |
2023 | fndecl = get_callee_fndecl (arg0); |
2024 | if (fndecl == NULL_TREE | |
2025 | || ! (flags_from_decl_or_type (fndecl) & ECF_CONST)) | |
21c43754 RS |
2026 | return 0; |
2027 | ||
2028 | /* Now see if all the arguments are the same. operand_equal_p | |
2029 | does not handle TREE_LIST, so we walk the operands here | |
2030 | feeding them to operand_equal_p. */ | |
2031 | arg0 = TREE_OPERAND (arg0, 1); | |
2032 | arg1 = TREE_OPERAND (arg1, 1); | |
2033 | while (arg0 && arg1) | |
2034 | { | |
2035 | if (! operand_equal_p (TREE_VALUE (arg0), TREE_VALUE (arg1), 0)) | |
2036 | return 0; | |
2037 | ||
2038 | arg0 = TREE_CHAIN (arg0); | |
2039 | arg1 = TREE_CHAIN (arg1); | |
2040 | } | |
2041 | ||
2042 | /* If we get here and both argument lists are exhausted | |
2043 | then the CALL_EXPRs are equal. */ | |
2044 | return ! (arg0 || arg1); | |
2045 | ||
1bfedcc8 JM |
2046 | default: |
2047 | return 0; | |
2048 | } | |
b6cc0a72 | 2049 | |
21c43754 RS |
2050 | case 'd': |
2051 | /* Consider __builtin_sqrt equal to sqrt. */ | |
2052 | return TREE_CODE (arg0) == FUNCTION_DECL | |
2053 | && DECL_BUILT_IN (arg0) && DECL_BUILT_IN (arg1) | |
2054 | && DECL_BUILT_IN_CLASS (arg0) == DECL_BUILT_IN_CLASS (arg1) | |
2055 | && DECL_FUNCTION_CODE (arg0) == DECL_FUNCTION_CODE (arg1); | |
2056 | ||
e9a25f70 JL |
2057 | default: |
2058 | return 0; | |
6d716ca8 | 2059 | } |
6d716ca8 | 2060 | } |
c05a9b68 RS |
2061 | \f |
2062 | /* Similar to operand_equal_p, but see if ARG0 might have been made by | |
b6cc0a72 | 2063 | shorten_compare from ARG1 when ARG1 was being compared with OTHER. |
6d716ca8 | 2064 | |
6d716ca8 RS |
2065 | When in doubt, return 0. */ |
2066 | ||
b6cc0a72 | 2067 | static int |
fa8db1f7 | 2068 | operand_equal_for_comparison_p (tree arg0, tree arg1, tree other) |
6d716ca8 | 2069 | { |
c05a9b68 | 2070 | int unsignedp1, unsignedpo; |
52de9b6c | 2071 | tree primarg0, primarg1, primother; |
770ae6cc | 2072 | unsigned int correct_width; |
6d716ca8 | 2073 | |
c05a9b68 | 2074 | if (operand_equal_p (arg0, arg1, 0)) |
6d716ca8 RS |
2075 | return 1; |
2076 | ||
0982a4b8 JM |
2077 | if (! INTEGRAL_TYPE_P (TREE_TYPE (arg0)) |
2078 | || ! INTEGRAL_TYPE_P (TREE_TYPE (arg1))) | |
6d716ca8 RS |
2079 | return 0; |
2080 | ||
52de9b6c RK |
2081 | /* Discard any conversions that don't change the modes of ARG0 and ARG1 |
2082 | and see if the inner values are the same. This removes any | |
2083 | signedness comparison, which doesn't matter here. */ | |
2084 | primarg0 = arg0, primarg1 = arg1; | |
b6cc0a72 KH |
2085 | STRIP_NOPS (primarg0); |
2086 | STRIP_NOPS (primarg1); | |
52de9b6c RK |
2087 | if (operand_equal_p (primarg0, primarg1, 0)) |
2088 | return 1; | |
2089 | ||
c05a9b68 RS |
2090 | /* Duplicate what shorten_compare does to ARG1 and see if that gives the |
2091 | actual comparison operand, ARG0. | |
6d716ca8 | 2092 | |
c05a9b68 | 2093 | First throw away any conversions to wider types |
6d716ca8 | 2094 | already present in the operands. */ |
6d716ca8 | 2095 | |
c05a9b68 RS |
2096 | primarg1 = get_narrower (arg1, &unsignedp1); |
2097 | primother = get_narrower (other, &unsignedpo); | |
2098 | ||
2099 | correct_width = TYPE_PRECISION (TREE_TYPE (arg1)); | |
2100 | if (unsignedp1 == unsignedpo | |
2101 | && TYPE_PRECISION (TREE_TYPE (primarg1)) < correct_width | |
2102 | && TYPE_PRECISION (TREE_TYPE (primother)) < correct_width) | |
6d716ca8 | 2103 | { |
c05a9b68 | 2104 | tree type = TREE_TYPE (arg0); |
6d716ca8 RS |
2105 | |
2106 | /* Make sure shorter operand is extended the right way | |
2107 | to match the longer operand. */ | |
ceef8ce4 NB |
2108 | primarg1 = convert ((*lang_hooks.types.signed_or_unsigned_type) |
2109 | (unsignedp1, TREE_TYPE (primarg1)), primarg1); | |
6d716ca8 | 2110 | |
c05a9b68 | 2111 | if (operand_equal_p (arg0, convert (type, primarg1), 0)) |
6d716ca8 RS |
2112 | return 1; |
2113 | } | |
2114 | ||
2115 | return 0; | |
2116 | } | |
2117 | \f | |
f72aed24 | 2118 | /* See if ARG is an expression that is either a comparison or is performing |
c05a9b68 RS |
2119 | arithmetic on comparisons. The comparisons must only be comparing |
2120 | two different values, which will be stored in *CVAL1 and *CVAL2; if | |
cc2902df | 2121 | they are nonzero it means that some operands have already been found. |
c05a9b68 | 2122 | No variables may be used anywhere else in the expression except in the |
35e66bd1 RK |
2123 | comparisons. If SAVE_P is true it means we removed a SAVE_EXPR around |
2124 | the expression and save_expr needs to be called with CVAL1 and CVAL2. | |
c05a9b68 RS |
2125 | |
2126 | If this is true, return 1. Otherwise, return zero. */ | |
2127 | ||
2128 | static int | |
fa8db1f7 | 2129 | twoval_comparison_p (tree arg, tree *cval1, tree *cval2, int *save_p) |
c05a9b68 RS |
2130 | { |
2131 | enum tree_code code = TREE_CODE (arg); | |
2132 | char class = TREE_CODE_CLASS (code); | |
2133 | ||
2134 | /* We can handle some of the 'e' cases here. */ | |
35e66bd1 | 2135 | if (class == 'e' && code == TRUTH_NOT_EXPR) |
c05a9b68 RS |
2136 | class = '1'; |
2137 | else if (class == 'e' | |
2138 | && (code == TRUTH_ANDIF_EXPR || code == TRUTH_ORIF_EXPR | |
2139 | || code == COMPOUND_EXPR)) | |
2140 | class = '2'; | |
2315a5db | 2141 | |
d4b60170 RK |
2142 | else if (class == 'e' && code == SAVE_EXPR && SAVE_EXPR_RTL (arg) == 0 |
2143 | && ! TREE_SIDE_EFFECTS (TREE_OPERAND (arg, 0))) | |
35e66bd1 RK |
2144 | { |
2145 | /* If we've already found a CVAL1 or CVAL2, this expression is | |
2146 | two complex to handle. */ | |
2147 | if (*cval1 || *cval2) | |
2148 | return 0; | |
2149 | ||
2150 | class = '1'; | |
2151 | *save_p = 1; | |
2152 | } | |
c05a9b68 RS |
2153 | |
2154 | switch (class) | |
2155 | { | |
2156 | case '1': | |
35e66bd1 | 2157 | return twoval_comparison_p (TREE_OPERAND (arg, 0), cval1, cval2, save_p); |
c05a9b68 RS |
2158 | |
2159 | case '2': | |
35e66bd1 RK |
2160 | return (twoval_comparison_p (TREE_OPERAND (arg, 0), cval1, cval2, save_p) |
2161 | && twoval_comparison_p (TREE_OPERAND (arg, 1), | |
2162 | cval1, cval2, save_p)); | |
c05a9b68 RS |
2163 | |
2164 | case 'c': | |
2165 | return 1; | |
2166 | ||
2167 | case 'e': | |
2168 | if (code == COND_EXPR) | |
35e66bd1 RK |
2169 | return (twoval_comparison_p (TREE_OPERAND (arg, 0), |
2170 | cval1, cval2, save_p) | |
2171 | && twoval_comparison_p (TREE_OPERAND (arg, 1), | |
2172 | cval1, cval2, save_p) | |
c05a9b68 | 2173 | && twoval_comparison_p (TREE_OPERAND (arg, 2), |
35e66bd1 | 2174 | cval1, cval2, save_p)); |
c05a9b68 | 2175 | return 0; |
b6cc0a72 | 2176 | |
c05a9b68 RS |
2177 | case '<': |
2178 | /* First see if we can handle the first operand, then the second. For | |
2179 | the second operand, we know *CVAL1 can't be zero. It must be that | |
2180 | one side of the comparison is each of the values; test for the | |
2181 | case where this isn't true by failing if the two operands | |
2182 | are the same. */ | |
2183 | ||
2184 | if (operand_equal_p (TREE_OPERAND (arg, 0), | |
2185 | TREE_OPERAND (arg, 1), 0)) | |
2186 | return 0; | |
2187 | ||
2188 | if (*cval1 == 0) | |
2189 | *cval1 = TREE_OPERAND (arg, 0); | |
2190 | else if (operand_equal_p (*cval1, TREE_OPERAND (arg, 0), 0)) | |
2191 | ; | |
2192 | else if (*cval2 == 0) | |
2193 | *cval2 = TREE_OPERAND (arg, 0); | |
2194 | else if (operand_equal_p (*cval2, TREE_OPERAND (arg, 0), 0)) | |
2195 | ; | |
2196 | else | |
2197 | return 0; | |
2198 | ||
2199 | if (operand_equal_p (*cval1, TREE_OPERAND (arg, 1), 0)) | |
2200 | ; | |
2201 | else if (*cval2 == 0) | |
2202 | *cval2 = TREE_OPERAND (arg, 1); | |
2203 | else if (operand_equal_p (*cval2, TREE_OPERAND (arg, 1), 0)) | |
2204 | ; | |
2205 | else | |
2206 | return 0; | |
2207 | ||
2208 | return 1; | |
c05a9b68 | 2209 | |
e9a25f70 JL |
2210 | default: |
2211 | return 0; | |
2212 | } | |
c05a9b68 RS |
2213 | } |
2214 | \f | |
2215 | /* ARG is a tree that is known to contain just arithmetic operations and | |
2216 | comparisons. Evaluate the operations in the tree substituting NEW0 for | |
f72aed24 | 2217 | any occurrence of OLD0 as an operand of a comparison and likewise for |
c05a9b68 RS |
2218 | NEW1 and OLD1. */ |
2219 | ||
2220 | static tree | |
fa8db1f7 | 2221 | eval_subst (tree arg, tree old0, tree new0, tree old1, tree new1) |
c05a9b68 RS |
2222 | { |
2223 | tree type = TREE_TYPE (arg); | |
2224 | enum tree_code code = TREE_CODE (arg); | |
2225 | char class = TREE_CODE_CLASS (code); | |
2226 | ||
2227 | /* We can handle some of the 'e' cases here. */ | |
2228 | if (class == 'e' && code == TRUTH_NOT_EXPR) | |
2229 | class = '1'; | |
2230 | else if (class == 'e' | |
2231 | && (code == TRUTH_ANDIF_EXPR || code == TRUTH_ORIF_EXPR)) | |
2232 | class = '2'; | |
2233 | ||
2234 | switch (class) | |
2235 | { | |
2236 | case '1': | |
2237 | return fold (build1 (code, type, | |
2238 | eval_subst (TREE_OPERAND (arg, 0), | |
2239 | old0, new0, old1, new1))); | |
2240 | ||
2241 | case '2': | |
2242 | return fold (build (code, type, | |
2243 | eval_subst (TREE_OPERAND (arg, 0), | |
2244 | old0, new0, old1, new1), | |
2245 | eval_subst (TREE_OPERAND (arg, 1), | |
2246 | old0, new0, old1, new1))); | |
2247 | ||
2248 | case 'e': | |
2249 | switch (code) | |
2250 | { | |
2251 | case SAVE_EXPR: | |
2252 | return eval_subst (TREE_OPERAND (arg, 0), old0, new0, old1, new1); | |
2253 | ||
2254 | case COMPOUND_EXPR: | |
2255 | return eval_subst (TREE_OPERAND (arg, 1), old0, new0, old1, new1); | |
2256 | ||
2257 | case COND_EXPR: | |
2258 | return fold (build (code, type, | |
2259 | eval_subst (TREE_OPERAND (arg, 0), | |
2260 | old0, new0, old1, new1), | |
2261 | eval_subst (TREE_OPERAND (arg, 1), | |
2262 | old0, new0, old1, new1), | |
2263 | eval_subst (TREE_OPERAND (arg, 2), | |
2264 | old0, new0, old1, new1))); | |
e9a25f70 JL |
2265 | default: |
2266 | break; | |
c05a9b68 | 2267 | } |
938d968e | 2268 | /* Fall through - ??? */ |
c05a9b68 RS |
2269 | |
2270 | case '<': | |
2271 | { | |
2272 | tree arg0 = TREE_OPERAND (arg, 0); | |
2273 | tree arg1 = TREE_OPERAND (arg, 1); | |
2274 | ||
2275 | /* We need to check both for exact equality and tree equality. The | |
2276 | former will be true if the operand has a side-effect. In that | |
2277 | case, we know the operand occurred exactly once. */ | |
2278 | ||
2279 | if (arg0 == old0 || operand_equal_p (arg0, old0, 0)) | |
2280 | arg0 = new0; | |
2281 | else if (arg0 == old1 || operand_equal_p (arg0, old1, 0)) | |
2282 | arg0 = new1; | |
2283 | ||
2284 | if (arg1 == old0 || operand_equal_p (arg1, old0, 0)) | |
2285 | arg1 = new0; | |
2286 | else if (arg1 == old1 || operand_equal_p (arg1, old1, 0)) | |
2287 | arg1 = new1; | |
2288 | ||
2289 | return fold (build (code, type, arg0, arg1)); | |
2290 | } | |
c05a9b68 | 2291 | |
e9a25f70 JL |
2292 | default: |
2293 | return arg; | |
2294 | } | |
c05a9b68 RS |
2295 | } |
2296 | \f | |
6d716ca8 RS |
2297 | /* Return a tree for the case when the result of an expression is RESULT |
2298 | converted to TYPE and OMITTED was previously an operand of the expression | |
2299 | but is now not needed (e.g., we folded OMITTED * 0). | |
2300 | ||
2301 | If OMITTED has side effects, we must evaluate it. Otherwise, just do | |
2302 | the conversion of RESULT to TYPE. */ | |
2303 | ||
c0a47a61 | 2304 | tree |
fa8db1f7 | 2305 | omit_one_operand (tree type, tree result, tree omitted) |
6d716ca8 RS |
2306 | { |
2307 | tree t = convert (type, result); | |
2308 | ||
2309 | if (TREE_SIDE_EFFECTS (omitted)) | |
2310 | return build (COMPOUND_EXPR, type, omitted, t); | |
2311 | ||
d023bff9 | 2312 | return non_lvalue (t); |
6d716ca8 | 2313 | } |
4ab3cb65 RK |
2314 | |
2315 | /* Similar, but call pedantic_non_lvalue instead of non_lvalue. */ | |
2316 | ||
2317 | static tree | |
fa8db1f7 | 2318 | pedantic_omit_one_operand (tree type, tree result, tree omitted) |
4ab3cb65 RK |
2319 | { |
2320 | tree t = convert (type, result); | |
2321 | ||
2322 | if (TREE_SIDE_EFFECTS (omitted)) | |
2323 | return build (COMPOUND_EXPR, type, omitted, t); | |
2324 | ||
2325 | return pedantic_non_lvalue (t); | |
2326 | } | |
6d716ca8 | 2327 | \f |
3f783329 RS |
2328 | /* Return a simplified tree node for the truth-negation of ARG. This |
2329 | never alters ARG itself. We assume that ARG is an operation that | |
6d716ca8 RS |
2330 | returns a truth value (0 or 1). */ |
2331 | ||
2332 | tree | |
fa8db1f7 | 2333 | invert_truthvalue (tree arg) |
6d716ca8 RS |
2334 | { |
2335 | tree type = TREE_TYPE (arg); | |
c05a9b68 | 2336 | enum tree_code code = TREE_CODE (arg); |
6d716ca8 | 2337 | |
8ac1abdf JW |
2338 | if (code == ERROR_MARK) |
2339 | return arg; | |
2340 | ||
c05a9b68 RS |
2341 | /* If this is a comparison, we can simply invert it, except for |
2342 | floating-point non-equality comparisons, in which case we just | |
2343 | enclose a TRUTH_NOT_EXPR around what we have. */ | |
6d716ca8 | 2344 | |
c05a9b68 | 2345 | if (TREE_CODE_CLASS (code) == '<') |
6d716ca8 | 2346 | { |
7178e3af | 2347 | if (FLOAT_TYPE_P (TREE_TYPE (TREE_OPERAND (arg, 0))) |
de6c5979 | 2348 | && !flag_unsafe_math_optimizations |
dd3f0101 | 2349 | && code != NE_EXPR |
de6c5979 | 2350 | && code != EQ_EXPR) |
c05a9b68 RS |
2351 | return build1 (TRUTH_NOT_EXPR, type, arg); |
2352 | else | |
ca46db87 | 2353 | return build (invert_tree_comparison (code), type, |
3f783329 | 2354 | TREE_OPERAND (arg, 0), TREE_OPERAND (arg, 1)); |
c05a9b68 | 2355 | } |
6d716ca8 | 2356 | |
c05a9b68 RS |
2357 | switch (code) |
2358 | { | |
6d716ca8 | 2359 | case INTEGER_CST: |
05bccae2 | 2360 | return convert (type, build_int_2 (integer_zerop (arg), 0)); |
6d716ca8 RS |
2361 | |
2362 | case TRUTH_AND_EXPR: | |
2363 | return build (TRUTH_OR_EXPR, type, | |
2364 | invert_truthvalue (TREE_OPERAND (arg, 0)), | |
2365 | invert_truthvalue (TREE_OPERAND (arg, 1))); | |
2366 | ||
2367 | case TRUTH_OR_EXPR: | |
2368 | return build (TRUTH_AND_EXPR, type, | |
2369 | invert_truthvalue (TREE_OPERAND (arg, 0)), | |
2370 | invert_truthvalue (TREE_OPERAND (arg, 1))); | |
2371 | ||
772447c5 RK |
2372 | case TRUTH_XOR_EXPR: |
2373 | /* Here we can invert either operand. We invert the first operand | |
2374 | unless the second operand is a TRUTH_NOT_EXPR in which case our | |
2375 | result is the XOR of the first operand with the inside of the | |
2376 | negation of the second operand. */ | |
2377 | ||
2378 | if (TREE_CODE (TREE_OPERAND (arg, 1)) == TRUTH_NOT_EXPR) | |
2379 | return build (TRUTH_XOR_EXPR, type, TREE_OPERAND (arg, 0), | |
2380 | TREE_OPERAND (TREE_OPERAND (arg, 1), 0)); | |
2381 | else | |
2382 | return build (TRUTH_XOR_EXPR, type, | |
2383 | invert_truthvalue (TREE_OPERAND (arg, 0)), | |
2384 | TREE_OPERAND (arg, 1)); | |
2385 | ||
6d716ca8 RS |
2386 | case TRUTH_ANDIF_EXPR: |
2387 | return build (TRUTH_ORIF_EXPR, type, | |
2388 | invert_truthvalue (TREE_OPERAND (arg, 0)), | |
2389 | invert_truthvalue (TREE_OPERAND (arg, 1))); | |
2390 | ||
2391 | case TRUTH_ORIF_EXPR: | |
2392 | return build (TRUTH_ANDIF_EXPR, type, | |
2393 | invert_truthvalue (TREE_OPERAND (arg, 0)), | |
2394 | invert_truthvalue (TREE_OPERAND (arg, 1))); | |
2395 | ||
2396 | case TRUTH_NOT_EXPR: | |
2397 | return TREE_OPERAND (arg, 0); | |
2398 | ||
2399 | case COND_EXPR: | |
2400 | return build (COND_EXPR, type, TREE_OPERAND (arg, 0), | |
2401 | invert_truthvalue (TREE_OPERAND (arg, 1)), | |
2402 | invert_truthvalue (TREE_OPERAND (arg, 2))); | |
2403 | ||
ef9fe0da RK |
2404 | case COMPOUND_EXPR: |
2405 | return build (COMPOUND_EXPR, type, TREE_OPERAND (arg, 0), | |
2406 | invert_truthvalue (TREE_OPERAND (arg, 1))); | |
2407 | ||
14a774a9 RK |
2408 | case WITH_RECORD_EXPR: |
2409 | return build (WITH_RECORD_EXPR, type, | |
2410 | invert_truthvalue (TREE_OPERAND (arg, 0)), | |
2411 | TREE_OPERAND (arg, 1)); | |
2412 | ||
6d716ca8 RS |
2413 | case NON_LVALUE_EXPR: |
2414 | return invert_truthvalue (TREE_OPERAND (arg, 0)); | |
2415 | ||
2416 | case NOP_EXPR: | |
2417 | case CONVERT_EXPR: | |
2418 | case FLOAT_EXPR: | |
2419 | return build1 (TREE_CODE (arg), type, | |
2420 | invert_truthvalue (TREE_OPERAND (arg, 0))); | |
2421 | ||
2422 | case BIT_AND_EXPR: | |
efc1a4d9 PB |
2423 | if (!integer_onep (TREE_OPERAND (arg, 1))) |
2424 | break; | |
6d716ca8 | 2425 | return build (EQ_EXPR, type, arg, convert (type, integer_zero_node)); |
6d716ca8 | 2426 | |
dfa90b42 RS |
2427 | case SAVE_EXPR: |
2428 | return build1 (TRUTH_NOT_EXPR, type, arg); | |
a25ee332 RK |
2429 | |
2430 | case CLEANUP_POINT_EXPR: | |
2431 | return build1 (CLEANUP_POINT_EXPR, type, | |
2432 | invert_truthvalue (TREE_OPERAND (arg, 0))); | |
e9a25f70 JL |
2433 | |
2434 | default: | |
2435 | break; | |
efc1a4d9 PB |
2436 | } |
2437 | if (TREE_CODE (TREE_TYPE (arg)) != BOOLEAN_TYPE) | |
dfa90b42 | 2438 | abort (); |
efc1a4d9 | 2439 | return build1 (TRUTH_NOT_EXPR, type, arg); |
6d716ca8 RS |
2440 | } |
2441 | ||
2442 | /* Given a bit-wise operation CODE applied to ARG0 and ARG1, see if both | |
2443 | operands are another bit-wise operation with a common input. If so, | |
2444 | distribute the bit operations to save an operation and possibly two if | |
2445 | constants are involved. For example, convert | |
fa8db1f7 | 2446 | (A | B) & (A | C) into A | (B & C) |
6d716ca8 RS |
2447 | Further simplification will occur if B and C are constants. |
2448 | ||
2449 | If this optimization cannot be done, 0 will be returned. */ | |
2450 | ||
2451 | static tree | |
fa8db1f7 | 2452 | distribute_bit_expr (enum tree_code code, tree type, tree arg0, tree arg1) |
6d716ca8 RS |
2453 | { |
2454 | tree common; | |
2455 | tree left, right; | |
2456 | ||
2457 | if (TREE_CODE (arg0) != TREE_CODE (arg1) | |
2458 | || TREE_CODE (arg0) == code | |
fced8ba3 RS |
2459 | || (TREE_CODE (arg0) != BIT_AND_EXPR |
2460 | && TREE_CODE (arg0) != BIT_IOR_EXPR)) | |
6d716ca8 RS |
2461 | return 0; |
2462 | ||
2463 | if (operand_equal_p (TREE_OPERAND (arg0, 0), TREE_OPERAND (arg1, 0), 0)) | |
2464 | { | |
2465 | common = TREE_OPERAND (arg0, 0); | |
2466 | left = TREE_OPERAND (arg0, 1); | |
2467 | right = TREE_OPERAND (arg1, 1); | |
2468 | } | |
2469 | else if (operand_equal_p (TREE_OPERAND (arg0, 0), TREE_OPERAND (arg1, 1), 0)) | |
2470 | { | |
2471 | common = TREE_OPERAND (arg0, 0); | |
2472 | left = TREE_OPERAND (arg0, 1); | |
2473 | right = TREE_OPERAND (arg1, 0); | |
2474 | } | |
2475 | else if (operand_equal_p (TREE_OPERAND (arg0, 1), TREE_OPERAND (arg1, 0), 0)) | |
2476 | { | |
2477 | common = TREE_OPERAND (arg0, 1); | |
2478 | left = TREE_OPERAND (arg0, 0); | |
2479 | right = TREE_OPERAND (arg1, 1); | |
2480 | } | |
2481 | else if (operand_equal_p (TREE_OPERAND (arg0, 1), TREE_OPERAND (arg1, 1), 0)) | |
2482 | { | |
2483 | common = TREE_OPERAND (arg0, 1); | |
2484 | left = TREE_OPERAND (arg0, 0); | |
2485 | right = TREE_OPERAND (arg1, 0); | |
2486 | } | |
2487 | else | |
2488 | return 0; | |
2489 | ||
2490 | return fold (build (TREE_CODE (arg0), type, common, | |
2491 | fold (build (code, type, left, right)))); | |
2492 | } | |
2493 | \f | |
2494 | /* Return a BIT_FIELD_REF of type TYPE to refer to BITSIZE bits of INNER | |
cc2902df | 2495 | starting at BITPOS. The field is unsigned if UNSIGNEDP is nonzero. */ |
6d716ca8 RS |
2496 | |
2497 | static tree | |
75040a04 AJ |
2498 | make_bit_field_ref (tree inner, tree type, int bitsize, int bitpos, |
2499 | int unsignedp) | |
6d716ca8 RS |
2500 | { |
2501 | tree result = build (BIT_FIELD_REF, type, inner, | |
06ceef4e | 2502 | size_int (bitsize), bitsize_int (bitpos)); |
6d716ca8 RS |
2503 | |
2504 | TREE_UNSIGNED (result) = unsignedp; | |
2505 | ||
2506 | return result; | |
2507 | } | |
2508 | ||
2509 | /* Optimize a bit-field compare. | |
2510 | ||
2511 | There are two cases: First is a compare against a constant and the | |
2512 | second is a comparison of two items where the fields are at the same | |
2513 | bit position relative to the start of a chunk (byte, halfword, word) | |
2514 | large enough to contain it. In these cases we can avoid the shift | |
2515 | implicit in bitfield extractions. | |
2516 | ||
2517 | For constants, we emit a compare of the shifted constant with the | |
2518 | BIT_AND_EXPR of a mask and a byte, halfword, or word of the operand being | |
2519 | compared. For two fields at the same position, we do the ANDs with the | |
2520 | similar mask and compare the result of the ANDs. | |
2521 | ||
2522 | CODE is the comparison code, known to be either NE_EXPR or EQ_EXPR. | |
2523 | COMPARE_TYPE is the type of the comparison, and LHS and RHS | |
2524 | are the left and right operands of the comparison, respectively. | |
2525 | ||
6dc42e49 | 2526 | If the optimization described above can be done, we return the resulting |
6d716ca8 RS |
2527 | tree. Otherwise we return zero. */ |
2528 | ||
2529 | static tree | |
75040a04 AJ |
2530 | optimize_bit_field_compare (enum tree_code code, tree compare_type, |
2531 | tree lhs, tree rhs) | |
6d716ca8 | 2532 | { |
770ae6cc | 2533 | HOST_WIDE_INT lbitpos, lbitsize, rbitpos, rbitsize, nbitpos, nbitsize; |
6d716ca8 RS |
2534 | tree type = TREE_TYPE (lhs); |
2535 | tree signed_type, unsigned_type; | |
2536 | int const_p = TREE_CODE (rhs) == INTEGER_CST; | |
5826cacf | 2537 | enum machine_mode lmode, rmode, nmode; |
6d716ca8 RS |
2538 | int lunsignedp, runsignedp; |
2539 | int lvolatilep = 0, rvolatilep = 0; | |
4e86caed | 2540 | tree linner, rinner = NULL_TREE; |
6d716ca8 | 2541 | tree mask; |
f1e60ec6 | 2542 | tree offset; |
6d716ca8 RS |
2543 | |
2544 | /* Get all the information about the extractions being done. If the bit size | |
2545 | if the same as the size of the underlying object, we aren't doing an | |
14a774a9 RK |
2546 | extraction at all and so can do nothing. We also don't want to |
2547 | do anything if the inner expression is a PLACEHOLDER_EXPR since we | |
2548 | then will no longer be able to replace it. */ | |
f1e60ec6 | 2549 | linner = get_inner_reference (lhs, &lbitsize, &lbitpos, &offset, &lmode, |
a06ef755 | 2550 | &lunsignedp, &lvolatilep); |
9f5e873c | 2551 | if (linner == lhs || lbitsize == GET_MODE_BITSIZE (lmode) || lbitsize < 0 |
14a774a9 | 2552 | || offset != 0 || TREE_CODE (linner) == PLACEHOLDER_EXPR) |
6d716ca8 RS |
2553 | return 0; |
2554 | ||
2555 | if (!const_p) | |
2556 | { | |
2557 | /* If this is not a constant, we can only do something if bit positions, | |
6d2f8887 | 2558 | sizes, and signedness are the same. */ |
23bd99ae | 2559 | rinner = get_inner_reference (rhs, &rbitsize, &rbitpos, &offset, &rmode, |
a06ef755 | 2560 | &runsignedp, &rvolatilep); |
6d716ca8 | 2561 | |
9f5e873c | 2562 | if (rinner == rhs || lbitpos != rbitpos || lbitsize != rbitsize |
14a774a9 RK |
2563 | || lunsignedp != runsignedp || offset != 0 |
2564 | || TREE_CODE (rinner) == PLACEHOLDER_EXPR) | |
6d716ca8 RS |
2565 | return 0; |
2566 | } | |
2567 | ||
2568 | /* See if we can find a mode to refer to this field. We should be able to, | |
2569 | but fail if we can't. */ | |
5826cacf RK |
2570 | nmode = get_best_mode (lbitsize, lbitpos, |
2571 | const_p ? TYPE_ALIGN (TREE_TYPE (linner)) | |
2572 | : MIN (TYPE_ALIGN (TREE_TYPE (linner)), | |
2573 | TYPE_ALIGN (TREE_TYPE (rinner))), | |
2574 | word_mode, lvolatilep || rvolatilep); | |
2575 | if (nmode == VOIDmode) | |
6d716ca8 RS |
2576 | return 0; |
2577 | ||
2578 | /* Set signed and unsigned types of the precision of this mode for the | |
2579 | shifts below. */ | |
b0c48229 NB |
2580 | signed_type = (*lang_hooks.types.type_for_mode) (nmode, 0); |
2581 | unsigned_type = (*lang_hooks.types.type_for_mode) (nmode, 1); | |
6d716ca8 | 2582 | |
6d716ca8 RS |
2583 | /* Compute the bit position and size for the new reference and our offset |
2584 | within it. If the new reference is the same size as the original, we | |
2585 | won't optimize anything, so return zero. */ | |
5826cacf RK |
2586 | nbitsize = GET_MODE_BITSIZE (nmode); |
2587 | nbitpos = lbitpos & ~ (nbitsize - 1); | |
2588 | lbitpos -= nbitpos; | |
2589 | if (nbitsize == lbitsize) | |
6d716ca8 RS |
2590 | return 0; |
2591 | ||
f76b9db2 | 2592 | if (BYTES_BIG_ENDIAN) |
5826cacf | 2593 | lbitpos = nbitsize - lbitsize - lbitpos; |
6d716ca8 RS |
2594 | |
2595 | /* Make the mask to be used against the extracted field. */ | |
13af526d RS |
2596 | mask = build_int_2 (~0, ~0); |
2597 | TREE_TYPE (mask) = unsigned_type; | |
aa830baf | 2598 | force_fit_type (mask, 0); |
13af526d | 2599 | mask = convert (unsigned_type, mask); |
5826cacf | 2600 | mask = const_binop (LSHIFT_EXPR, mask, size_int (nbitsize - lbitsize), 0); |
6d716ca8 | 2601 | mask = const_binop (RSHIFT_EXPR, mask, |
5826cacf | 2602 | size_int (nbitsize - lbitsize - lbitpos), 0); |
6d716ca8 RS |
2603 | |
2604 | if (! const_p) | |
2605 | /* If not comparing with constant, just rework the comparison | |
2606 | and return. */ | |
2607 | return build (code, compare_type, | |
c0b9d4c8 RK |
2608 | build (BIT_AND_EXPR, unsigned_type, |
2609 | make_bit_field_ref (linner, unsigned_type, | |
5826cacf | 2610 | nbitsize, nbitpos, 1), |
6d716ca8 | 2611 | mask), |
c0b9d4c8 RK |
2612 | build (BIT_AND_EXPR, unsigned_type, |
2613 | make_bit_field_ref (rinner, unsigned_type, | |
5826cacf | 2614 | nbitsize, nbitpos, 1), |
6d716ca8 RS |
2615 | mask)); |
2616 | ||
2617 | /* Otherwise, we are handling the constant case. See if the constant is too | |
2618 | big for the field. Warn and return a tree of for 0 (false) if so. We do | |
2619 | this not only for its own sake, but to avoid having to test for this | |
2620 | error case below. If we didn't, we might generate wrong code. | |
2621 | ||
2622 | For unsigned fields, the constant shifted right by the field length should | |
b6cc0a72 | 2623 | be all zero. For signed fields, the high-order bits should agree with |
6d716ca8 RS |
2624 | the sign bit. */ |
2625 | ||
2626 | if (lunsignedp) | |
2627 | { | |
2628 | if (! integer_zerop (const_binop (RSHIFT_EXPR, | |
2629 | convert (unsigned_type, rhs), | |
91d33e36 | 2630 | size_int (lbitsize), 0))) |
6d716ca8 | 2631 | { |
b0287a90 | 2632 | warning ("comparison is always %d due to width of bit-field", |
ab87f8c8 | 2633 | code == NE_EXPR); |
6d716ca8 RS |
2634 | return convert (compare_type, |
2635 | (code == NE_EXPR | |
2636 | ? integer_one_node : integer_zero_node)); | |
2637 | } | |
2638 | } | |
2639 | else | |
2640 | { | |
2641 | tree tem = const_binop (RSHIFT_EXPR, convert (signed_type, rhs), | |
91d33e36 | 2642 | size_int (lbitsize - 1), 0); |
6d716ca8 RS |
2643 | if (! integer_zerop (tem) && ! integer_all_onesp (tem)) |
2644 | { | |
b0287a90 | 2645 | warning ("comparison is always %d due to width of bit-field", |
ab87f8c8 | 2646 | code == NE_EXPR); |
6d716ca8 RS |
2647 | return convert (compare_type, |
2648 | (code == NE_EXPR | |
2649 | ? integer_one_node : integer_zero_node)); | |
2650 | } | |
2651 | } | |
2652 | ||
2653 | /* Single-bit compares should always be against zero. */ | |
2654 | if (lbitsize == 1 && ! integer_zerop (rhs)) | |
2655 | { | |
2656 | code = code == EQ_EXPR ? NE_EXPR : EQ_EXPR; | |
2657 | rhs = convert (type, integer_zero_node); | |
2658 | } | |
2659 | ||
2660 | /* Make a new bitfield reference, shift the constant over the | |
2661 | appropriate number of bits and mask it with the computed mask | |
2662 | (in case this was a signed field). If we changed it, make a new one. */ | |
5826cacf | 2663 | lhs = make_bit_field_ref (linner, unsigned_type, nbitsize, nbitpos, 1); |
9db73acb RK |
2664 | if (lvolatilep) |
2665 | { | |
2666 | TREE_SIDE_EFFECTS (lhs) = 1; | |
2667 | TREE_THIS_VOLATILE (lhs) = 1; | |
2668 | } | |
6d716ca8 | 2669 | |
c0b9d4c8 RK |
2670 | rhs = fold (const_binop (BIT_AND_EXPR, |
2671 | const_binop (LSHIFT_EXPR, | |
2672 | convert (unsigned_type, rhs), | |
194c082f | 2673 | size_int (lbitpos), 0), |
91d33e36 | 2674 | mask, 0)); |
6d716ca8 RS |
2675 | |
2676 | return build (code, compare_type, | |
c0b9d4c8 | 2677 | build (BIT_AND_EXPR, unsigned_type, lhs, mask), |
6d716ca8 RS |
2678 | rhs); |
2679 | } | |
2680 | \f | |
b2215d83 | 2681 | /* Subroutine for fold_truthop: decode a field reference. |
6d716ca8 RS |
2682 | |
2683 | If EXP is a comparison reference, we return the innermost reference. | |
2684 | ||
2685 | *PBITSIZE is set to the number of bits in the reference, *PBITPOS is | |
2686 | set to the starting bit number. | |
2687 | ||
2688 | If the innermost field can be completely contained in a mode-sized | |
2689 | unit, *PMODE is set to that mode. Otherwise, it is set to VOIDmode. | |
2690 | ||
2691 | *PVOLATILEP is set to 1 if the any expression encountered is volatile; | |
2692 | otherwise it is not changed. | |
2693 | ||
2694 | *PUNSIGNEDP is set to the signedness of the field. | |
2695 | ||
2696 | *PMASK is set to the mask used. This is either contained in a | |
2697 | BIT_AND_EXPR or derived from the width of the field. | |
2698 | ||
38e01259 | 2699 | *PAND_MASK is set to the mask found in a BIT_AND_EXPR, if any. |
d4453ee5 | 2700 | |
6d716ca8 RS |
2701 | Return 0 if this is not a component reference or is one that we can't |
2702 | do anything with. */ | |
2703 | ||
2704 | static tree | |
75040a04 AJ |
2705 | decode_field_reference (tree exp, HOST_WIDE_INT *pbitsize, |
2706 | HOST_WIDE_INT *pbitpos, enum machine_mode *pmode, | |
2707 | int *punsignedp, int *pvolatilep, | |
fa8db1f7 | 2708 | tree *pmask, tree *pand_mask) |
6d716ca8 | 2709 | { |
1a8c4ca6 | 2710 | tree outer_type = 0; |
6d9f1f5f RK |
2711 | tree and_mask = 0; |
2712 | tree mask, inner, offset; | |
2713 | tree unsigned_type; | |
770ae6cc | 2714 | unsigned int precision; |
6d716ca8 | 2715 | |
b6cc0a72 | 2716 | /* All the optimizations using this function assume integer fields. |
772ae9f0 RK |
2717 | There are problems with FP fields since the type_for_size call |
2718 | below can fail for, e.g., XFmode. */ | |
2719 | if (! INTEGRAL_TYPE_P (TREE_TYPE (exp))) | |
2720 | return 0; | |
2721 | ||
1a8c4ca6 EB |
2722 | /* We are interested in the bare arrangement of bits, so strip everything |
2723 | that doesn't affect the machine mode. However, record the type of the | |
2724 | outermost expression if it may matter below. */ | |
2725 | if (TREE_CODE (exp) == NOP_EXPR | |
2726 | || TREE_CODE (exp) == CONVERT_EXPR | |
2727 | || TREE_CODE (exp) == NON_LVALUE_EXPR) | |
2728 | outer_type = TREE_TYPE (exp); | |
df7fb8f9 | 2729 | STRIP_NOPS (exp); |
6d716ca8 RS |
2730 | |
2731 | if (TREE_CODE (exp) == BIT_AND_EXPR) | |
2732 | { | |
6d9f1f5f | 2733 | and_mask = TREE_OPERAND (exp, 1); |
6d716ca8 | 2734 | exp = TREE_OPERAND (exp, 0); |
6d9f1f5f RK |
2735 | STRIP_NOPS (exp); STRIP_NOPS (and_mask); |
2736 | if (TREE_CODE (and_mask) != INTEGER_CST) | |
6d716ca8 RS |
2737 | return 0; |
2738 | } | |
2739 | ||
f1e60ec6 | 2740 | inner = get_inner_reference (exp, pbitsize, pbitpos, &offset, pmode, |
a06ef755 | 2741 | punsignedp, pvolatilep); |
02103577 | 2742 | if ((inner == exp && and_mask == 0) |
14a774a9 RK |
2743 | || *pbitsize < 0 || offset != 0 |
2744 | || TREE_CODE (inner) == PLACEHOLDER_EXPR) | |
c05a9b68 | 2745 | return 0; |
b6cc0a72 | 2746 | |
1a8c4ca6 EB |
2747 | /* If the number of bits in the reference is the same as the bitsize of |
2748 | the outer type, then the outer type gives the signedness. Otherwise | |
2749 | (in case of a small bitfield) the signedness is unchanged. */ | |
2750 | if (outer_type && *pbitsize == tree_low_cst (TYPE_SIZE (outer_type), 1)) | |
2751 | *punsignedp = TREE_UNSIGNED (outer_type); | |
2752 | ||
6d9f1f5f | 2753 | /* Compute the mask to access the bitfield. */ |
b0c48229 | 2754 | unsigned_type = (*lang_hooks.types.type_for_size) (*pbitsize, 1); |
6d9f1f5f RK |
2755 | precision = TYPE_PRECISION (unsigned_type); |
2756 | ||
2757 | mask = build_int_2 (~0, ~0); | |
2758 | TREE_TYPE (mask) = unsigned_type; | |
2759 | force_fit_type (mask, 0); | |
2760 | mask = const_binop (LSHIFT_EXPR, mask, size_int (precision - *pbitsize), 0); | |
2761 | mask = const_binop (RSHIFT_EXPR, mask, size_int (precision - *pbitsize), 0); | |
2762 | ||
2763 | /* Merge it with the mask we found in the BIT_AND_EXPR, if any. */ | |
2764 | if (and_mask != 0) | |
2765 | mask = fold (build (BIT_AND_EXPR, unsigned_type, | |
2766 | convert (unsigned_type, and_mask), mask)); | |
6d716ca8 RS |
2767 | |
2768 | *pmask = mask; | |
d4453ee5 | 2769 | *pand_mask = and_mask; |
6d716ca8 RS |
2770 | return inner; |
2771 | } | |
2772 | ||
cc2902df | 2773 | /* Return nonzero if MASK represents a mask of SIZE ones in the low-order |
6d716ca8 RS |
2774 | bit positions. */ |
2775 | ||
2776 | static int | |
fa8db1f7 | 2777 | all_ones_mask_p (tree mask, int size) |
6d716ca8 RS |
2778 | { |
2779 | tree type = TREE_TYPE (mask); | |
770ae6cc | 2780 | unsigned int precision = TYPE_PRECISION (type); |
13af526d | 2781 | tree tmask; |
6d716ca8 | 2782 | |
13af526d | 2783 | tmask = build_int_2 (~0, ~0); |
ceef8ce4 | 2784 | TREE_TYPE (tmask) = (*lang_hooks.types.signed_type) (type); |
aa830baf | 2785 | force_fit_type (tmask, 0); |
6d716ca8 | 2786 | return |
b6cc0a72 | 2787 | tree_int_cst_equal (mask, |
02103577 RK |
2788 | const_binop (RSHIFT_EXPR, |
2789 | const_binop (LSHIFT_EXPR, tmask, | |
2790 | size_int (precision - size), | |
2791 | 0), | |
2792 | size_int (precision - size), 0)); | |
6d716ca8 | 2793 | } |
b2215d83 | 2794 | |
1f77b5da RS |
2795 | /* Subroutine for fold: determine if VAL is the INTEGER_CONST that |
2796 | represents the sign bit of EXP's type. If EXP represents a sign | |
2797 | or zero extension, also test VAL against the unextended type. | |
2798 | The return value is the (sub)expression whose sign bit is VAL, | |
2799 | or NULL_TREE otherwise. */ | |
2800 | ||
2801 | static tree | |
fa8db1f7 | 2802 | sign_bit_p (tree exp, tree val) |
1f77b5da | 2803 | { |
c87d821b KH |
2804 | unsigned HOST_WIDE_INT mask_lo, lo; |
2805 | HOST_WIDE_INT mask_hi, hi; | |
1f77b5da RS |
2806 | int width; |
2807 | tree t; | |
2808 | ||
68e82b83 | 2809 | /* Tree EXP must have an integral type. */ |
1f77b5da RS |
2810 | t = TREE_TYPE (exp); |
2811 | if (! INTEGRAL_TYPE_P (t)) | |
2812 | return NULL_TREE; | |
2813 | ||
2814 | /* Tree VAL must be an integer constant. */ | |
2815 | if (TREE_CODE (val) != INTEGER_CST | |
2816 | || TREE_CONSTANT_OVERFLOW (val)) | |
2817 | return NULL_TREE; | |
2818 | ||
2819 | width = TYPE_PRECISION (t); | |
2820 | if (width > HOST_BITS_PER_WIDE_INT) | |
2821 | { | |
2822 | hi = (unsigned HOST_WIDE_INT) 1 << (width - HOST_BITS_PER_WIDE_INT - 1); | |
2823 | lo = 0; | |
c87d821b KH |
2824 | |
2825 | mask_hi = ((unsigned HOST_WIDE_INT) -1 | |
2826 | >> (2 * HOST_BITS_PER_WIDE_INT - width)); | |
2827 | mask_lo = -1; | |
1f77b5da RS |
2828 | } |
2829 | else | |
2830 | { | |
2831 | hi = 0; | |
2832 | lo = (unsigned HOST_WIDE_INT) 1 << (width - 1); | |
c87d821b KH |
2833 | |
2834 | mask_hi = 0; | |
2835 | mask_lo = ((unsigned HOST_WIDE_INT) -1 | |
2836 | >> (HOST_BITS_PER_WIDE_INT - width)); | |
1f77b5da RS |
2837 | } |
2838 | ||
c87d821b KH |
2839 | /* We mask off those bits beyond TREE_TYPE (exp) so that we can |
2840 | treat VAL as if it were unsigned. */ | |
2841 | if ((TREE_INT_CST_HIGH (val) & mask_hi) == hi | |
2842 | && (TREE_INT_CST_LOW (val) & mask_lo) == lo) | |
1f77b5da RS |
2843 | return exp; |
2844 | ||
2845 | /* Handle extension from a narrower type. */ | |
2846 | if (TREE_CODE (exp) == NOP_EXPR | |
2847 | && TYPE_PRECISION (TREE_TYPE (TREE_OPERAND (exp, 0))) < width) | |
2848 | return sign_bit_p (TREE_OPERAND (exp, 0), val); | |
2849 | ||
2850 | return NULL_TREE; | |
2851 | } | |
2852 | ||
b2215d83 TW |
2853 | /* Subroutine for fold_truthop: determine if an operand is simple enough |
2854 | to be evaluated unconditionally. */ | |
2855 | ||
b6cc0a72 | 2856 | static int |
fa8db1f7 | 2857 | simple_operand_p (tree exp) |
b2215d83 TW |
2858 | { |
2859 | /* Strip any conversions that don't change the machine mode. */ | |
2860 | while ((TREE_CODE (exp) == NOP_EXPR | |
2861 | || TREE_CODE (exp) == CONVERT_EXPR) | |
2862 | && (TYPE_MODE (TREE_TYPE (exp)) | |
2863 | == TYPE_MODE (TREE_TYPE (TREE_OPERAND (exp, 0))))) | |
2864 | exp = TREE_OPERAND (exp, 0); | |
2865 | ||
2866 | return (TREE_CODE_CLASS (TREE_CODE (exp)) == 'c' | |
2f939d94 | 2867 | || (DECL_P (exp) |
b2215d83 TW |
2868 | && ! TREE_ADDRESSABLE (exp) |
2869 | && ! TREE_THIS_VOLATILE (exp) | |
8227896c TW |
2870 | && ! DECL_NONLOCAL (exp) |
2871 | /* Don't regard global variables as simple. They may be | |
2872 | allocated in ways unknown to the compiler (shared memory, | |
2873 | #pragma weak, etc). */ | |
2874 | && ! TREE_PUBLIC (exp) | |
2875 | && ! DECL_EXTERNAL (exp) | |
2876 | /* Loading a static variable is unduly expensive, but global | |
2877 | registers aren't expensive. */ | |
2878 | && (! TREE_STATIC (exp) || DECL_REGISTER (exp)))); | |
b2215d83 | 2879 | } |
6d716ca8 | 2880 | \f |
ebde8a27 RK |
2881 | /* The following functions are subroutines to fold_range_test and allow it to |
2882 | try to change a logical combination of comparisons into a range test. | |
2883 | ||
2884 | For example, both | |
fa8db1f7 | 2885 | X == 2 || X == 3 || X == 4 || X == 5 |
ebde8a27 | 2886 | and |
fa8db1f7 | 2887 | X >= 2 && X <= 5 |
ebde8a27 RK |
2888 | are converted to |
2889 | (unsigned) (X - 2) <= 3 | |
2890 | ||
956d6950 | 2891 | We describe each set of comparisons as being either inside or outside |
ebde8a27 RK |
2892 | a range, using a variable named like IN_P, and then describe the |
2893 | range with a lower and upper bound. If one of the bounds is omitted, | |
2894 | it represents either the highest or lowest value of the type. | |
2895 | ||
2896 | In the comments below, we represent a range by two numbers in brackets | |
956d6950 | 2897 | preceded by a "+" to designate being inside that range, or a "-" to |
ebde8a27 RK |
2898 | designate being outside that range, so the condition can be inverted by |
2899 | flipping the prefix. An omitted bound is represented by a "-". For | |
2900 | example, "- [-, 10]" means being outside the range starting at the lowest | |
2901 | possible value and ending at 10, in other words, being greater than 10. | |
2902 | The range "+ [-, -]" is always true and hence the range "- [-, -]" is | |
2903 | always false. | |
2904 | ||
2905 | We set up things so that the missing bounds are handled in a consistent | |
2906 | manner so neither a missing bound nor "true" and "false" need to be | |
2907 | handled using a special case. */ | |
2908 | ||
2909 | /* Return the result of applying CODE to ARG0 and ARG1, but handle the case | |
2910 | of ARG0 and/or ARG1 being omitted, meaning an unlimited range. UPPER0_P | |
2911 | and UPPER1_P are nonzero if the respective argument is an upper bound | |
2912 | and zero for a lower. TYPE, if nonzero, is the type of the result; it | |
2913 | must be specified for a comparison. ARG1 will be converted to ARG0's | |
2914 | type if both are specified. */ | |
ef659ec0 | 2915 | |
ebde8a27 | 2916 | static tree |
75040a04 AJ |
2917 | range_binop (enum tree_code code, tree type, tree arg0, int upper0_p, |
2918 | tree arg1, int upper1_p) | |
ebde8a27 | 2919 | { |
27bae8e5 | 2920 | tree tem; |
ebde8a27 RK |
2921 | int result; |
2922 | int sgn0, sgn1; | |
ef659ec0 | 2923 | |
ebde8a27 RK |
2924 | /* If neither arg represents infinity, do the normal operation. |
2925 | Else, if not a comparison, return infinity. Else handle the special | |
2926 | comparison rules. Note that most of the cases below won't occur, but | |
2927 | are handled for consistency. */ | |
ef659ec0 | 2928 | |
ebde8a27 | 2929 | if (arg0 != 0 && arg1 != 0) |
27bae8e5 RK |
2930 | { |
2931 | tem = fold (build (code, type != 0 ? type : TREE_TYPE (arg0), | |
2932 | arg0, convert (TREE_TYPE (arg0), arg1))); | |
2933 | STRIP_NOPS (tem); | |
2934 | return TREE_CODE (tem) == INTEGER_CST ? tem : 0; | |
2935 | } | |
ef659ec0 | 2936 | |
ebde8a27 RK |
2937 | if (TREE_CODE_CLASS (code) != '<') |
2938 | return 0; | |
2939 | ||
2940 | /* Set SGN[01] to -1 if ARG[01] is a lower bound, 1 for upper, and 0 | |
d7b3ea38 NS |
2941 | for neither. In real maths, we cannot assume open ended ranges are |
2942 | the same. But, this is computer arithmetic, where numbers are finite. | |
2943 | We can therefore make the transformation of any unbounded range with | |
2944 | the value Z, Z being greater than any representable number. This permits | |
30f7a378 | 2945 | us to treat unbounded ranges as equal. */ |
ebde8a27 | 2946 | sgn0 = arg0 != 0 ? 0 : (upper0_p ? 1 : -1); |
4e644c93 | 2947 | sgn1 = arg1 != 0 ? 0 : (upper1_p ? 1 : -1); |
ebde8a27 RK |
2948 | switch (code) |
2949 | { | |
d7b3ea38 NS |
2950 | case EQ_EXPR: |
2951 | result = sgn0 == sgn1; | |
2952 | break; | |
2953 | case NE_EXPR: | |
2954 | result = sgn0 != sgn1; | |
ebde8a27 | 2955 | break; |
d7b3ea38 | 2956 | case LT_EXPR: |
ebde8a27 RK |
2957 | result = sgn0 < sgn1; |
2958 | break; | |
d7b3ea38 NS |
2959 | case LE_EXPR: |
2960 | result = sgn0 <= sgn1; | |
2961 | break; | |
2962 | case GT_EXPR: | |
ebde8a27 RK |
2963 | result = sgn0 > sgn1; |
2964 | break; | |
d7b3ea38 NS |
2965 | case GE_EXPR: |
2966 | result = sgn0 >= sgn1; | |
2967 | break; | |
e9a25f70 JL |
2968 | default: |
2969 | abort (); | |
ebde8a27 RK |
2970 | } |
2971 | ||
2972 | return convert (type, result ? integer_one_node : integer_zero_node); | |
2973 | } | |
b6cc0a72 | 2974 | \f |
ebde8a27 RK |
2975 | /* Given EXP, a logical expression, set the range it is testing into |
2976 | variables denoted by PIN_P, PLOW, and PHIGH. Return the expression | |
f42ef510 | 2977 | actually being tested. *PLOW and *PHIGH will be made of the same type |
ebde8a27 RK |
2978 | as the returned expression. If EXP is not a comparison, we will most |
2979 | likely not be returning a useful value and range. */ | |
ef659ec0 | 2980 | |
6dc7571d | 2981 | static tree |
fa8db1f7 | 2982 | make_range (tree exp, int *pin_p, tree *plow, tree *phigh) |
ef659ec0 | 2983 | { |
ebde8a27 | 2984 | enum tree_code code; |
07444f1d | 2985 | tree arg0 = NULL_TREE, arg1 = NULL_TREE, type = NULL_TREE; |
7d12cee1 | 2986 | tree orig_type = NULL_TREE; |
ebde8a27 RK |
2987 | int in_p, n_in_p; |
2988 | tree low, high, n_low, n_high; | |
ef659ec0 | 2989 | |
ebde8a27 RK |
2990 | /* Start with simply saying "EXP != 0" and then look at the code of EXP |
2991 | and see if we can refine the range. Some of the cases below may not | |
2992 | happen, but it doesn't seem worth worrying about this. We "continue" | |
2993 | the outer loop when we've changed something; otherwise we "break" | |
2994 | the switch, which will "break" the while. */ | |
ef659ec0 | 2995 | |
ebde8a27 RK |
2996 | in_p = 0, low = high = convert (TREE_TYPE (exp), integer_zero_node); |
2997 | ||
2998 | while (1) | |
ef659ec0 | 2999 | { |
ebde8a27 | 3000 | code = TREE_CODE (exp); |
30d68b86 MM |
3001 | |
3002 | if (IS_EXPR_CODE_CLASS (TREE_CODE_CLASS (code))) | |
3003 | { | |
d17811fd MM |
3004 | if (first_rtl_op (code) > 0) |
3005 | arg0 = TREE_OPERAND (exp, 0); | |
b6cc0a72 | 3006 | if (TREE_CODE_CLASS (code) == '<' |
30d68b86 MM |
3007 | || TREE_CODE_CLASS (code) == '1' |
3008 | || TREE_CODE_CLASS (code) == '2') | |
3009 | type = TREE_TYPE (arg0); | |
b6cc0a72 | 3010 | if (TREE_CODE_CLASS (code) == '2' |
30d68b86 | 3011 | || TREE_CODE_CLASS (code) == '<' |
b6cc0a72 | 3012 | || (TREE_CODE_CLASS (code) == 'e' |
efd58783 | 3013 | && TREE_CODE_LENGTH (code) > 1)) |
30d68b86 MM |
3014 | arg1 = TREE_OPERAND (exp, 1); |
3015 | } | |
ef659ec0 | 3016 | |
cc33944a RE |
3017 | /* Set ORIG_TYPE as soon as TYPE is non-null so that we do not |
3018 | lose a cast by accident. */ | |
3019 | if (type != NULL_TREE && orig_type == NULL_TREE) | |
3020 | orig_type = type; | |
3021 | ||
ebde8a27 RK |
3022 | switch (code) |
3023 | { | |
3024 | case TRUTH_NOT_EXPR: | |
3025 | in_p = ! in_p, exp = arg0; | |
3026 | continue; | |
3027 | ||
3028 | case EQ_EXPR: case NE_EXPR: | |
3029 | case LT_EXPR: case LE_EXPR: case GE_EXPR: case GT_EXPR: | |
3030 | /* We can only do something if the range is testing for zero | |
3031 | and if the second operand is an integer constant. Note that | |
3032 | saying something is "in" the range we make is done by | |
3033 | complementing IN_P since it will set in the initial case of | |
3034 | being not equal to zero; "out" is leaving it alone. */ | |
3035 | if (low == 0 || high == 0 | |
3036 | || ! integer_zerop (low) || ! integer_zerop (high) | |
3037 | || TREE_CODE (arg1) != INTEGER_CST) | |
3038 | break; | |
ef659ec0 | 3039 | |
ebde8a27 RK |
3040 | switch (code) |
3041 | { | |
3042 | case NE_EXPR: /* - [c, c] */ | |
3043 | low = high = arg1; | |
3044 | break; | |
3045 | case EQ_EXPR: /* + [c, c] */ | |
3046 | in_p = ! in_p, low = high = arg1; | |
3047 | break; | |
3048 | case GT_EXPR: /* - [-, c] */ | |
3049 | low = 0, high = arg1; | |
3050 | break; | |
3051 | case GE_EXPR: /* + [c, -] */ | |
3052 | in_p = ! in_p, low = arg1, high = 0; | |
3053 | break; | |
3054 | case LT_EXPR: /* - [c, -] */ | |
3055 | low = arg1, high = 0; | |
3056 | break; | |
3057 | case LE_EXPR: /* + [-, c] */ | |
3058 | in_p = ! in_p, low = 0, high = arg1; | |
3059 | break; | |
e9a25f70 JL |
3060 | default: |
3061 | abort (); | |
ebde8a27 | 3062 | } |
ef659ec0 | 3063 | |
ebde8a27 | 3064 | exp = arg0; |
ef659ec0 | 3065 | |
7f423031 | 3066 | /* If this is an unsigned comparison, we also know that EXP is |
0e1c7fc7 RK |
3067 | greater than or equal to zero. We base the range tests we make |
3068 | on that fact, so we record it here so we can parse existing | |
3069 | range tests. */ | |
7f423031 | 3070 | if (TREE_UNSIGNED (type) && (low == 0 || high == 0)) |
ebde8a27 RK |
3071 | { |
3072 | if (! merge_ranges (&n_in_p, &n_low, &n_high, in_p, low, high, | |
3073 | 1, convert (type, integer_zero_node), | |
0e1c7fc7 | 3074 | NULL_TREE)) |
ebde8a27 | 3075 | break; |
ef659ec0 | 3076 | |
ebde8a27 | 3077 | in_p = n_in_p, low = n_low, high = n_high; |
0e1c7fc7 | 3078 | |
c565a6b7 R |
3079 | /* If the high bound is missing, but we |
3080 | have a low bound, reverse the range so | |
3081 | it goes from zero to the low bound minus 1. */ | |
3082 | if (high == 0 && low) | |
0e1c7fc7 RK |
3083 | { |
3084 | in_p = ! in_p; | |
3085 | high = range_binop (MINUS_EXPR, NULL_TREE, low, 0, | |
3086 | integer_one_node, 0); | |
3087 | low = convert (type, integer_zero_node); | |
3088 | } | |
ebde8a27 RK |
3089 | } |
3090 | continue; | |
3091 | ||
3092 | case NEGATE_EXPR: | |
3093 | /* (-x) IN [a,b] -> x in [-b, -a] */ | |
3094 | n_low = range_binop (MINUS_EXPR, type, | |
3095 | convert (type, integer_zero_node), 0, high, 1); | |
3096 | n_high = range_binop (MINUS_EXPR, type, | |
3097 | convert (type, integer_zero_node), 0, low, 0); | |
3098 | low = n_low, high = n_high; | |
3099 | exp = arg0; | |
3100 | continue; | |
3101 | ||
3102 | case BIT_NOT_EXPR: | |
3103 | /* ~ X -> -X - 1 */ | |
1baa375f | 3104 | exp = build (MINUS_EXPR, type, negate_expr (arg0), |
27bae8e5 | 3105 | convert (type, integer_one_node)); |
ebde8a27 RK |
3106 | continue; |
3107 | ||
3108 | case PLUS_EXPR: case MINUS_EXPR: | |
3109 | if (TREE_CODE (arg1) != INTEGER_CST) | |
3110 | break; | |
3111 | ||
3112 | /* If EXP is signed, any overflow in the computation is undefined, | |
3113 | so we don't worry about it so long as our computations on | |
3114 | the bounds don't overflow. For unsigned, overflow is defined | |
3115 | and this is exactly the right thing. */ | |
3116 | n_low = range_binop (code == MINUS_EXPR ? PLUS_EXPR : MINUS_EXPR, | |
3117 | type, low, 0, arg1, 0); | |
3118 | n_high = range_binop (code == MINUS_EXPR ? PLUS_EXPR : MINUS_EXPR, | |
3119 | type, high, 1, arg1, 0); | |
3120 | if ((n_low != 0 && TREE_OVERFLOW (n_low)) | |
3121 | || (n_high != 0 && TREE_OVERFLOW (n_high))) | |
3122 | break; | |
3123 | ||
3c00684e JL |
3124 | /* Check for an unsigned range which has wrapped around the maximum |
3125 | value thus making n_high < n_low, and normalize it. */ | |
5a9d82a6 | 3126 | if (n_low && n_high && tree_int_cst_lt (n_high, n_low)) |
3c00684e JL |
3127 | { |
3128 | low = range_binop (PLUS_EXPR, type, n_high, 0, | |
0e1c7fc7 | 3129 | integer_one_node, 0); |
3c00684e | 3130 | high = range_binop (MINUS_EXPR, type, n_low, 0, |
c2b63960 AO |
3131 | integer_one_node, 0); |
3132 | ||
3133 | /* If the range is of the form +/- [ x+1, x ], we won't | |
3134 | be able to normalize it. But then, it represents the | |
3135 | whole range or the empty set, so make it | |
3136 | +/- [ -, - ]. */ | |
3137 | if (tree_int_cst_equal (n_low, low) | |
3138 | && tree_int_cst_equal (n_high, high)) | |
3139 | low = high = 0; | |
3140 | else | |
3141 | in_p = ! in_p; | |
3c00684e | 3142 | } |
5a9d82a6 JW |
3143 | else |
3144 | low = n_low, high = n_high; | |
27bae8e5 | 3145 | |
ebde8a27 RK |
3146 | exp = arg0; |
3147 | continue; | |
3148 | ||
3149 | case NOP_EXPR: case NON_LVALUE_EXPR: case CONVERT_EXPR: | |
7d12cee1 JL |
3150 | if (TYPE_PRECISION (type) > TYPE_PRECISION (orig_type)) |
3151 | break; | |
3152 | ||
ebde8a27 RK |
3153 | if (! INTEGRAL_TYPE_P (type) |
3154 | || (low != 0 && ! int_fits_type_p (low, type)) | |
3155 | || (high != 0 && ! int_fits_type_p (high, type))) | |
3156 | break; | |
3157 | ||
ce2157a1 | 3158 | n_low = low, n_high = high; |
ebde8a27 | 3159 | |
ce2157a1 JL |
3160 | if (n_low != 0) |
3161 | n_low = convert (type, n_low); | |
3162 | ||
3163 | if (n_high != 0) | |
3164 | n_high = convert (type, n_high); | |
3165 | ||
3166 | /* If we're converting from an unsigned to a signed type, | |
3167 | we will be doing the comparison as unsigned. The tests above | |
3168 | have already verified that LOW and HIGH are both positive. | |
3169 | ||
3170 | So we have to make sure that the original unsigned value will | |
3171 | be interpreted as positive. */ | |
3172 | if (TREE_UNSIGNED (type) && ! TREE_UNSIGNED (TREE_TYPE (exp))) | |
3173 | { | |
b0c48229 NB |
3174 | tree equiv_type = (*lang_hooks.types.type_for_mode) |
3175 | (TYPE_MODE (type), 1); | |
e1ee5cdc RH |
3176 | tree high_positive; |
3177 | ||
3178 | /* A range without an upper bound is, naturally, unbounded. | |
3179 | Since convert would have cropped a very large value, use | |
14a774a9 RK |
3180 | the max value for the destination type. */ |
3181 | high_positive | |
3182 | = TYPE_MAX_VALUE (equiv_type) ? TYPE_MAX_VALUE (equiv_type) | |
3183 | : TYPE_MAX_VALUE (type); | |
e1ee5cdc | 3184 | |
4f968d93 HP |
3185 | if (TYPE_PRECISION (type) == TYPE_PRECISION (TREE_TYPE (exp))) |
3186 | high_positive = fold (build (RSHIFT_EXPR, type, | |
3187 | convert (type, high_positive), | |
3188 | convert (type, integer_one_node))); | |
b6cc0a72 | 3189 | |
ce2157a1 JL |
3190 | /* If the low bound is specified, "and" the range with the |
3191 | range for which the original unsigned value will be | |
3192 | positive. */ | |
3193 | if (low != 0) | |
3194 | { | |
3195 | if (! merge_ranges (&n_in_p, &n_low, &n_high, | |
3196 | 1, n_low, n_high, | |
3197 | 1, convert (type, integer_zero_node), | |
3198 | high_positive)) | |
3199 | break; | |
3200 | ||
3201 | in_p = (n_in_p == in_p); | |
3202 | } | |
3203 | else | |
3204 | { | |
3205 | /* Otherwise, "or" the range with the range of the input | |
3206 | that will be interpreted as negative. */ | |
3207 | if (! merge_ranges (&n_in_p, &n_low, &n_high, | |
3208 | 0, n_low, n_high, | |
3209 | 1, convert (type, integer_zero_node), | |
3210 | high_positive)) | |
3211 | break; | |
3212 | ||
3213 | in_p = (in_p != n_in_p); | |
3214 | } | |
3215 | } | |
ebde8a27 RK |
3216 | |
3217 | exp = arg0; | |
ce2157a1 | 3218 | low = n_low, high = n_high; |
ebde8a27 | 3219 | continue; |
ce2157a1 JL |
3220 | |
3221 | default: | |
3222 | break; | |
ef659ec0 | 3223 | } |
ebde8a27 RK |
3224 | |
3225 | break; | |
ef659ec0 | 3226 | } |
ebde8a27 | 3227 | |
80906567 RK |
3228 | /* If EXP is a constant, we can evaluate whether this is true or false. */ |
3229 | if (TREE_CODE (exp) == INTEGER_CST) | |
3230 | { | |
3231 | in_p = in_p == (integer_onep (range_binop (GE_EXPR, integer_type_node, | |
3232 | exp, 0, low, 0)) | |
3233 | && integer_onep (range_binop (LE_EXPR, integer_type_node, | |
3234 | exp, 1, high, 1))); | |
3235 | low = high = 0; | |
3236 | exp = 0; | |
3237 | } | |
3238 | ||
ebde8a27 RK |
3239 | *pin_p = in_p, *plow = low, *phigh = high; |
3240 | return exp; | |
3241 | } | |
3242 | \f | |
3243 | /* Given a range, LOW, HIGH, and IN_P, an expression, EXP, and a result | |
3244 | type, TYPE, return an expression to test if EXP is in (or out of, depending | |
3245 | on IN_P) the range. */ | |
3246 | ||
3247 | static tree | |
fa8db1f7 | 3248 | build_range_check (tree type, tree exp, int in_p, tree low, tree high) |
ebde8a27 RK |
3249 | { |
3250 | tree etype = TREE_TYPE (exp); | |
dbfb1116 | 3251 | tree value; |
ebde8a27 RK |
3252 | |
3253 | if (! in_p | |
3254 | && (0 != (value = build_range_check (type, exp, 1, low, high)))) | |
3255 | return invert_truthvalue (value); | |
3256 | ||
dbfb1116 | 3257 | if (low == 0 && high == 0) |
ebde8a27 RK |
3258 | return convert (type, integer_one_node); |
3259 | ||
dbfb1116 | 3260 | if (low == 0) |
ebde8a27 RK |
3261 | return fold (build (LE_EXPR, type, exp, high)); |
3262 | ||
dbfb1116 | 3263 | if (high == 0) |
ebde8a27 RK |
3264 | return fold (build (GE_EXPR, type, exp, low)); |
3265 | ||
dbfb1116 | 3266 | if (operand_equal_p (low, high, 0)) |
ebde8a27 RK |
3267 | return fold (build (EQ_EXPR, type, exp, low)); |
3268 | ||
dbfb1116 | 3269 | if (integer_zerop (low)) |
ef659ec0 | 3270 | { |
dbfb1116 | 3271 | if (! TREE_UNSIGNED (etype)) |
dd3f0101 KH |
3272 | { |
3273 | etype = (*lang_hooks.types.unsigned_type) (etype); | |
3274 | high = convert (etype, high); | |
3275 | exp = convert (etype, exp); | |
3276 | } | |
dbfb1116 | 3277 | return build_range_check (type, exp, 1, 0, high); |
ebde8a27 | 3278 | } |
ef659ec0 | 3279 | |
dbfb1116 RS |
3280 | /* Optimize (c>=1) && (c<=127) into (signed char)c > 0. */ |
3281 | if (integer_onep (low) && TREE_CODE (high) == INTEGER_CST) | |
3282 | { | |
3283 | unsigned HOST_WIDE_INT lo; | |
3284 | HOST_WIDE_INT hi; | |
3285 | int prec; | |
3286 | ||
3287 | prec = TYPE_PRECISION (etype); | |
3288 | if (prec <= HOST_BITS_PER_WIDE_INT) | |
dd3f0101 KH |
3289 | { |
3290 | hi = 0; | |
3291 | lo = ((unsigned HOST_WIDE_INT) 1 << (prec - 1)) - 1; | |
3292 | } | |
dbfb1116 | 3293 | else |
dd3f0101 KH |
3294 | { |
3295 | hi = ((HOST_WIDE_INT) 1 << (prec - HOST_BITS_PER_WIDE_INT - 1)) - 1; | |
3296 | lo = (unsigned HOST_WIDE_INT) -1; | |
3297 | } | |
dbfb1116 RS |
3298 | |
3299 | if (TREE_INT_CST_HIGH (high) == hi && TREE_INT_CST_LOW (high) == lo) | |
dd3f0101 KH |
3300 | { |
3301 | if (TREE_UNSIGNED (etype)) | |
3302 | { | |
3303 | etype = (*lang_hooks.types.signed_type) (etype); | |
3304 | exp = convert (etype, exp); | |
3305 | } | |
3306 | return fold (build (GT_EXPR, type, exp, | |
3307 | convert (etype, integer_zero_node))); | |
3308 | } | |
dbfb1116 RS |
3309 | } |
3310 | ||
3311 | if (0 != (value = const_binop (MINUS_EXPR, high, low, 0)) | |
3312 | && ! TREE_OVERFLOW (value)) | |
ebde8a27 RK |
3313 | return build_range_check (type, |
3314 | fold (build (MINUS_EXPR, etype, exp, low)), | |
3315 | 1, convert (etype, integer_zero_node), value); | |
dbfb1116 RS |
3316 | |
3317 | return 0; | |
ebde8a27 RK |
3318 | } |
3319 | \f | |
b6cc0a72 | 3320 | /* Given two ranges, see if we can merge them into one. Return 1 if we |
ebde8a27 | 3321 | can, 0 if we can't. Set the output range into the specified parameters. */ |
ef659ec0 | 3322 | |
ebde8a27 | 3323 | static int |
75040a04 AJ |
3324 | merge_ranges (int *pin_p, tree *plow, tree *phigh, int in0_p, tree low0, |
3325 | tree high0, int in1_p, tree low1, tree high1) | |
ebde8a27 RK |
3326 | { |
3327 | int no_overlap; | |
3328 | int subset; | |
3329 | int temp; | |
3330 | tree tem; | |
3331 | int in_p; | |
3332 | tree low, high; | |
ce2157a1 JL |
3333 | int lowequal = ((low0 == 0 && low1 == 0) |
3334 | || integer_onep (range_binop (EQ_EXPR, integer_type_node, | |
3335 | low0, 0, low1, 0))); | |
3336 | int highequal = ((high0 == 0 && high1 == 0) | |
3337 | || integer_onep (range_binop (EQ_EXPR, integer_type_node, | |
3338 | high0, 1, high1, 1))); | |
3339 | ||
3340 | /* Make range 0 be the range that starts first, or ends last if they | |
3341 | start at the same value. Swap them if it isn't. */ | |
b6cc0a72 | 3342 | if (integer_onep (range_binop (GT_EXPR, integer_type_node, |
ebde8a27 | 3343 | low0, 0, low1, 0)) |
ce2157a1 | 3344 | || (lowequal |
ebde8a27 | 3345 | && integer_onep (range_binop (GT_EXPR, integer_type_node, |
ce2157a1 | 3346 | high1, 1, high0, 1)))) |
ebde8a27 RK |
3347 | { |
3348 | temp = in0_p, in0_p = in1_p, in1_p = temp; | |
3349 | tem = low0, low0 = low1, low1 = tem; | |
3350 | tem = high0, high0 = high1, high1 = tem; | |
3351 | } | |
ef659ec0 | 3352 | |
ebde8a27 RK |
3353 | /* Now flag two cases, whether the ranges are disjoint or whether the |
3354 | second range is totally subsumed in the first. Note that the tests | |
3355 | below are simplified by the ones above. */ | |
3356 | no_overlap = integer_onep (range_binop (LT_EXPR, integer_type_node, | |
3357 | high0, 1, low1, 0)); | |
5df8a1f2 | 3358 | subset = integer_onep (range_binop (LE_EXPR, integer_type_node, |
ebde8a27 RK |
3359 | high1, 1, high0, 1)); |
3360 | ||
3361 | /* We now have four cases, depending on whether we are including or | |
3362 | excluding the two ranges. */ | |
3363 | if (in0_p && in1_p) | |
3364 | { | |
3365 | /* If they don't overlap, the result is false. If the second range | |
3366 | is a subset it is the result. Otherwise, the range is from the start | |
3367 | of the second to the end of the first. */ | |
3368 | if (no_overlap) | |
3369 | in_p = 0, low = high = 0; | |
3370 | else if (subset) | |
3371 | in_p = 1, low = low1, high = high1; | |
3372 | else | |
3373 | in_p = 1, low = low1, high = high0; | |
3374 | } | |
ef659ec0 | 3375 | |
ebde8a27 RK |
3376 | else if (in0_p && ! in1_p) |
3377 | { | |
ce2157a1 JL |
3378 | /* If they don't overlap, the result is the first range. If they are |
3379 | equal, the result is false. If the second range is a subset of the | |
3380 | first, and the ranges begin at the same place, we go from just after | |
3381 | the end of the first range to the end of the second. If the second | |
3382 | range is not a subset of the first, or if it is a subset and both | |
3383 | ranges end at the same place, the range starts at the start of the | |
3384 | first range and ends just before the second range. | |
3385 | Otherwise, we can't describe this as a single range. */ | |
ebde8a27 RK |
3386 | if (no_overlap) |
3387 | in_p = 1, low = low0, high = high0; | |
ce2157a1 | 3388 | else if (lowequal && highequal) |
405862dd | 3389 | in_p = 0, low = high = 0; |
ce2157a1 JL |
3390 | else if (subset && lowequal) |
3391 | { | |
3392 | in_p = 1, high = high0; | |
3393 | low = range_binop (PLUS_EXPR, NULL_TREE, high1, 0, | |
b6cc0a72 | 3394 | integer_one_node, 0); |
ce2157a1 JL |
3395 | } |
3396 | else if (! subset || highequal) | |
ebde8a27 RK |
3397 | { |
3398 | in_p = 1, low = low0; | |
3399 | high = range_binop (MINUS_EXPR, NULL_TREE, low1, 0, | |
0e1c7fc7 | 3400 | integer_one_node, 0); |
ebde8a27 | 3401 | } |
ce2157a1 JL |
3402 | else |
3403 | return 0; | |
ebde8a27 | 3404 | } |
ef659ec0 | 3405 | |
ebde8a27 RK |
3406 | else if (! in0_p && in1_p) |
3407 | { | |
3408 | /* If they don't overlap, the result is the second range. If the second | |
3409 | is a subset of the first, the result is false. Otherwise, | |
3410 | the range starts just after the first range and ends at the | |
3411 | end of the second. */ | |
3412 | if (no_overlap) | |
3413 | in_p = 1, low = low1, high = high1; | |
14a774a9 | 3414 | else if (subset || highequal) |
ebde8a27 RK |
3415 | in_p = 0, low = high = 0; |
3416 | else | |
3417 | { | |
3418 | in_p = 1, high = high1; | |
3419 | low = range_binop (PLUS_EXPR, NULL_TREE, high0, 1, | |
3420 | integer_one_node, 0); | |
ef659ec0 TW |
3421 | } |
3422 | } | |
3423 | ||
ebde8a27 RK |
3424 | else |
3425 | { | |
3426 | /* The case where we are excluding both ranges. Here the complex case | |
3427 | is if they don't overlap. In that case, the only time we have a | |
3428 | range is if they are adjacent. If the second is a subset of the | |
3429 | first, the result is the first. Otherwise, the range to exclude | |
3430 | starts at the beginning of the first range and ends at the end of the | |
3431 | second. */ | |
3432 | if (no_overlap) | |
3433 | { | |
3434 | if (integer_onep (range_binop (EQ_EXPR, integer_type_node, | |
3435 | range_binop (PLUS_EXPR, NULL_TREE, | |
3436 | high0, 1, | |
3437 | integer_one_node, 1), | |
3438 | 1, low1, 0))) | |
3439 | in_p = 0, low = low0, high = high1; | |
3440 | else | |
3441 | return 0; | |
3442 | } | |
3443 | else if (subset) | |
3444 | in_p = 0, low = low0, high = high0; | |
3445 | else | |
3446 | in_p = 0, low = low0, high = high1; | |
3447 | } | |
f5902869 | 3448 | |
ebde8a27 RK |
3449 | *pin_p = in_p, *plow = low, *phigh = high; |
3450 | return 1; | |
3451 | } | |
3452 | \f | |
85e50b6b DE |
3453 | #ifndef RANGE_TEST_NON_SHORT_CIRCUIT |
3454 | #define RANGE_TEST_NON_SHORT_CIRCUIT (BRANCH_COST >= 2) | |
3455 | #endif | |
3456 | ||
ebde8a27 RK |
3457 | /* EXP is some logical combination of boolean tests. See if we can |
3458 | merge it into some range test. Return the new tree if so. */ | |
ef659ec0 | 3459 | |
ebde8a27 | 3460 | static tree |
fa8db1f7 | 3461 | fold_range_test (tree exp) |
ebde8a27 RK |
3462 | { |
3463 | int or_op = (TREE_CODE (exp) == TRUTH_ORIF_EXPR | |
3464 | || TREE_CODE (exp) == TRUTH_OR_EXPR); | |
3465 | int in0_p, in1_p, in_p; | |
3466 | tree low0, low1, low, high0, high1, high; | |
3467 | tree lhs = make_range (TREE_OPERAND (exp, 0), &in0_p, &low0, &high0); | |
3468 | tree rhs = make_range (TREE_OPERAND (exp, 1), &in1_p, &low1, &high1); | |
3469 | tree tem; | |
ef659ec0 | 3470 | |
ebde8a27 RK |
3471 | /* If this is an OR operation, invert both sides; we will invert |
3472 | again at the end. */ | |
3473 | if (or_op) | |
3474 | in0_p = ! in0_p, in1_p = ! in1_p; | |
3475 | ||
3476 | /* If both expressions are the same, if we can merge the ranges, and we | |
80906567 RK |
3477 | can build the range test, return it or it inverted. If one of the |
3478 | ranges is always true or always false, consider it to be the same | |
3479 | expression as the other. */ | |
3480 | if ((lhs == 0 || rhs == 0 || operand_equal_p (lhs, rhs, 0)) | |
ebde8a27 RK |
3481 | && merge_ranges (&in_p, &low, &high, in0_p, low0, high0, |
3482 | in1_p, low1, high1) | |
80906567 RK |
3483 | && 0 != (tem = (build_range_check (TREE_TYPE (exp), |
3484 | lhs != 0 ? lhs | |
3485 | : rhs != 0 ? rhs : integer_zero_node, | |
ebde8a27 RK |
3486 | in_p, low, high)))) |
3487 | return or_op ? invert_truthvalue (tem) : tem; | |
3488 | ||
3489 | /* On machines where the branch cost is expensive, if this is a | |
3490 | short-circuited branch and the underlying object on both sides | |
3491 | is the same, make a non-short-circuit operation. */ | |
85e50b6b | 3492 | else if (RANGE_TEST_NON_SHORT_CIRCUIT |
7cf5c9e1 | 3493 | && lhs != 0 && rhs != 0 |
ebde8a27 RK |
3494 | && (TREE_CODE (exp) == TRUTH_ANDIF_EXPR |
3495 | || TREE_CODE (exp) == TRUTH_ORIF_EXPR) | |
3496 | && operand_equal_p (lhs, rhs, 0)) | |
ef659ec0 | 3497 | { |
f0eebf28 | 3498 | /* If simple enough, just rewrite. Otherwise, make a SAVE_EXPR |
9ec36da5 JL |
3499 | unless we are at top level or LHS contains a PLACEHOLDER_EXPR, in |
3500 | which cases we can't do this. */ | |
ebde8a27 RK |
3501 | if (simple_operand_p (lhs)) |
3502 | return build (TREE_CODE (exp) == TRUTH_ANDIF_EXPR | |
3503 | ? TRUTH_AND_EXPR : TRUTH_OR_EXPR, | |
3504 | TREE_TYPE (exp), TREE_OPERAND (exp, 0), | |
3505 | TREE_OPERAND (exp, 1)); | |
f0eebf28 | 3506 | |
43577e6b | 3507 | else if ((*lang_hooks.decls.global_bindings_p) () == 0 |
7a6cdb44 | 3508 | && ! CONTAINS_PLACEHOLDER_P (lhs)) |
ebde8a27 RK |
3509 | { |
3510 | tree common = save_expr (lhs); | |
3511 | ||
3512 | if (0 != (lhs = build_range_check (TREE_TYPE (exp), common, | |
3513 | or_op ? ! in0_p : in0_p, | |
3514 | low0, high0)) | |
3515 | && (0 != (rhs = build_range_check (TREE_TYPE (exp), common, | |
3516 | or_op ? ! in1_p : in1_p, | |
3517 | low1, high1)))) | |
3518 | return build (TREE_CODE (exp) == TRUTH_ANDIF_EXPR | |
3519 | ? TRUTH_AND_EXPR : TRUTH_OR_EXPR, | |
3520 | TREE_TYPE (exp), lhs, rhs); | |
3521 | } | |
ef659ec0 | 3522 | } |
de153e82 | 3523 | |
de153e82 | 3524 | return 0; |
ef659ec0 TW |
3525 | } |
3526 | \f | |
02103577 | 3527 | /* Subroutine for fold_truthop: C is an INTEGER_CST interpreted as a P |
25216284 | 3528 | bit value. Arrange things so the extra bits will be set to zero if and |
d4453ee5 RK |
3529 | only if C is signed-extended to its full width. If MASK is nonzero, |
3530 | it is an INTEGER_CST that should be AND'ed with the extra bits. */ | |
02103577 RK |
3531 | |
3532 | static tree | |
fa8db1f7 | 3533 | unextend (tree c, int p, int unsignedp, tree mask) |
02103577 RK |
3534 | { |
3535 | tree type = TREE_TYPE (c); | |
3536 | int modesize = GET_MODE_BITSIZE (TYPE_MODE (type)); | |
3537 | tree temp; | |
3538 | ||
3539 | if (p == modesize || unsignedp) | |
3540 | return c; | |
3541 | ||
02103577 | 3542 | /* We work by getting just the sign bit into the low-order bit, then |
9faa82d8 | 3543 | into the high-order bit, then sign-extend. We then XOR that value |
02103577 RK |
3544 | with C. */ |
3545 | temp = const_binop (RSHIFT_EXPR, c, size_int (p - 1), 0); | |
3546 | temp = const_binop (BIT_AND_EXPR, temp, size_int (1), 0); | |
cf85c69b JW |
3547 | |
3548 | /* We must use a signed type in order to get an arithmetic right shift. | |
3549 | However, we must also avoid introducing accidental overflows, so that | |
b6cc0a72 | 3550 | a subsequent call to integer_zerop will work. Hence we must |
cf85c69b JW |
3551 | do the type conversion here. At this point, the constant is either |
3552 | zero or one, and the conversion to a signed type can never overflow. | |
3553 | We could get an overflow if this conversion is done anywhere else. */ | |
3554 | if (TREE_UNSIGNED (type)) | |
ceef8ce4 | 3555 | temp = convert ((*lang_hooks.types.signed_type) (type), temp); |
cf85c69b | 3556 | |
02103577 RK |
3557 | temp = const_binop (LSHIFT_EXPR, temp, size_int (modesize - 1), 0); |
3558 | temp = const_binop (RSHIFT_EXPR, temp, size_int (modesize - p - 1), 0); | |
d4453ee5 RK |
3559 | if (mask != 0) |
3560 | temp = const_binop (BIT_AND_EXPR, temp, convert (TREE_TYPE (c), mask), 0); | |
cf85c69b JW |
3561 | /* If necessary, convert the type back to match the type of C. */ |
3562 | if (TREE_UNSIGNED (type)) | |
3563 | temp = convert (type, temp); | |
d4453ee5 | 3564 | |
02103577 RK |
3565 | return convert (type, const_binop (BIT_XOR_EXPR, c, temp, 0)); |
3566 | } | |
3567 | \f | |
b2215d83 TW |
3568 | /* Find ways of folding logical expressions of LHS and RHS: |
3569 | Try to merge two comparisons to the same innermost item. | |
3570 | Look for range tests like "ch >= '0' && ch <= '9'". | |
3571 | Look for combinations of simple terms on machines with expensive branches | |
3572 | and evaluate the RHS unconditionally. | |
6d716ca8 RS |
3573 | |
3574 | For example, if we have p->a == 2 && p->b == 4 and we can make an | |
3575 | object large enough to span both A and B, we can do this with a comparison | |
3576 | against the object ANDed with the a mask. | |
3577 | ||
3578 | If we have p->a == q->a && p->b == q->b, we may be able to use bit masking | |
3579 | operations to do this with one comparison. | |
3580 | ||
3581 | We check for both normal comparisons and the BIT_AND_EXPRs made this by | |
3582 | function and the one above. | |
3583 | ||
3584 | CODE is the logical operation being done. It can be TRUTH_ANDIF_EXPR, | |
3585 | TRUTH_AND_EXPR, TRUTH_ORIF_EXPR, or TRUTH_OR_EXPR. | |
3586 | ||
3587 | TRUTH_TYPE is the type of the logical operand and LHS and RHS are its | |
3588 | two operands. | |
3589 | ||
3590 | We return the simplified tree or 0 if no optimization is possible. */ | |
3591 | ||
3592 | static tree | |
fa8db1f7 | 3593 | fold_truthop (enum tree_code code, tree truth_type, tree lhs, tree rhs) |
6d716ca8 | 3594 | { |
f42ef510 | 3595 | /* If this is the "or" of two comparisons, we can do something if |
6d716ca8 | 3596 | the comparisons are NE_EXPR. If this is the "and", we can do something |
b6cc0a72 | 3597 | if the comparisons are EQ_EXPR. I.e., |
fa8db1f7 | 3598 | (a->b == 2 && a->c == 4) can become (a->new == NEW). |
6d716ca8 RS |
3599 | |
3600 | WANTED_CODE is this operation code. For single bit fields, we can | |
3601 | convert EQ_EXPR to NE_EXPR so we need not reject the "wrong" | |
3602 | comparison for one-bit fields. */ | |
3603 | ||
b2215d83 | 3604 | enum tree_code wanted_code; |
6d716ca8 | 3605 | enum tree_code lcode, rcode; |
b2215d83 | 3606 | tree ll_arg, lr_arg, rl_arg, rr_arg; |
6d716ca8 | 3607 | tree ll_inner, lr_inner, rl_inner, rr_inner; |
770ae6cc RK |
3608 | HOST_WIDE_INT ll_bitsize, ll_bitpos, lr_bitsize, lr_bitpos; |
3609 | HOST_WIDE_INT rl_bitsize, rl_bitpos, rr_bitsize, rr_bitpos; | |
3610 | HOST_WIDE_INT xll_bitpos, xlr_bitpos, xrl_bitpos, xrr_bitpos; | |
3611 | HOST_WIDE_INT lnbitsize, lnbitpos, rnbitsize, rnbitpos; | |
6d716ca8 RS |
3612 | int ll_unsignedp, lr_unsignedp, rl_unsignedp, rr_unsignedp; |
3613 | enum machine_mode ll_mode, lr_mode, rl_mode, rr_mode; | |
3614 | enum machine_mode lnmode, rnmode; | |
3615 | tree ll_mask, lr_mask, rl_mask, rr_mask; | |
d4453ee5 | 3616 | tree ll_and_mask, lr_and_mask, rl_and_mask, rr_and_mask; |
b2215d83 | 3617 | tree l_const, r_const; |
bd910dcf | 3618 | tree lntype, rntype, result; |
6d716ca8 | 3619 | int first_bit, end_bit; |
b2215d83 | 3620 | int volatilep; |
6d716ca8 | 3621 | |
ebde8a27 RK |
3622 | /* Start by getting the comparison codes. Fail if anything is volatile. |
3623 | If one operand is a BIT_AND_EXPR with the constant one, treat it as if | |
3624 | it were surrounded with a NE_EXPR. */ | |
6d716ca8 | 3625 | |
ebde8a27 | 3626 | if (TREE_SIDE_EFFECTS (lhs) || TREE_SIDE_EFFECTS (rhs)) |
b2215d83 TW |
3627 | return 0; |
3628 | ||
6d716ca8 RS |
3629 | lcode = TREE_CODE (lhs); |
3630 | rcode = TREE_CODE (rhs); | |
ef659ec0 | 3631 | |
96d4cf0a RK |
3632 | if (lcode == BIT_AND_EXPR && integer_onep (TREE_OPERAND (lhs, 1))) |
3633 | lcode = NE_EXPR, lhs = build (NE_EXPR, truth_type, lhs, integer_zero_node); | |
3634 | ||
3635 | if (rcode == BIT_AND_EXPR && integer_onep (TREE_OPERAND (rhs, 1))) | |
3636 | rcode = NE_EXPR, rhs = build (NE_EXPR, truth_type, rhs, integer_zero_node); | |
3637 | ||
ebde8a27 | 3638 | if (TREE_CODE_CLASS (lcode) != '<' || TREE_CODE_CLASS (rcode) != '<') |
ef659ec0 TW |
3639 | return 0; |
3640 | ||
b2215d83 | 3641 | code = ((code == TRUTH_AND_EXPR || code == TRUTH_ANDIF_EXPR) |
9c0ae98b | 3642 | ? TRUTH_AND_EXPR : TRUTH_OR_EXPR); |
b2215d83 TW |
3643 | |
3644 | ll_arg = TREE_OPERAND (lhs, 0); | |
3645 | lr_arg = TREE_OPERAND (lhs, 1); | |
3646 | rl_arg = TREE_OPERAND (rhs, 0); | |
3647 | rr_arg = TREE_OPERAND (rhs, 1); | |
b6cc0a72 | 3648 | |
8dcb27ed RS |
3649 | /* Simplify (x<y) && (x==y) into (x<=y) and related optimizations. */ |
3650 | if (simple_operand_p (ll_arg) | |
3651 | && simple_operand_p (lr_arg) | |
3652 | && !FLOAT_TYPE_P (TREE_TYPE (ll_arg))) | |
3653 | { | |
3654 | int compcode; | |
3655 | ||
3656 | if (operand_equal_p (ll_arg, rl_arg, 0) | |
3657 | && operand_equal_p (lr_arg, rr_arg, 0)) | |
3658 | { | |
3659 | int lcompcode, rcompcode; | |
3660 | ||
3661 | lcompcode = comparison_to_compcode (lcode); | |
3662 | rcompcode = comparison_to_compcode (rcode); | |
3663 | compcode = (code == TRUTH_AND_EXPR) | |
3664 | ? lcompcode & rcompcode | |
3665 | : lcompcode | rcompcode; | |
3666 | } | |
3667 | else if (operand_equal_p (ll_arg, rr_arg, 0) | |
3668 | && operand_equal_p (lr_arg, rl_arg, 0)) | |
3669 | { | |
3670 | int lcompcode, rcompcode; | |
3671 | ||
3672 | rcode = swap_tree_comparison (rcode); | |
3673 | lcompcode = comparison_to_compcode (lcode); | |
3674 | rcompcode = comparison_to_compcode (rcode); | |
3675 | compcode = (code == TRUTH_AND_EXPR) | |
3676 | ? lcompcode & rcompcode | |
3677 | : lcompcode | rcompcode; | |
3678 | } | |
3679 | else | |
3680 | compcode = -1; | |
3681 | ||
3682 | if (compcode == COMPCODE_TRUE) | |
3683 | return convert (truth_type, integer_one_node); | |
3684 | else if (compcode == COMPCODE_FALSE) | |
3685 | return convert (truth_type, integer_zero_node); | |
3686 | else if (compcode != -1) | |
3687 | return build (compcode_to_comparison (compcode), | |
3688 | truth_type, ll_arg, lr_arg); | |
3689 | } | |
3690 | ||
8227896c | 3691 | /* If the RHS can be evaluated unconditionally and its operands are |
b2215d83 TW |
3692 | simple, it wins to evaluate the RHS unconditionally on machines |
3693 | with expensive branches. In this case, this isn't a comparison | |
1d691c53 RK |
3694 | that can be merged. Avoid doing this if the RHS is a floating-point |
3695 | comparison since those can trap. */ | |
b2215d83 TW |
3696 | |
3697 | if (BRANCH_COST >= 2 | |
1d691c53 | 3698 | && ! FLOAT_TYPE_P (TREE_TYPE (rl_arg)) |
b2215d83 | 3699 | && simple_operand_p (rl_arg) |
8227896c | 3700 | && simple_operand_p (rr_arg)) |
01c58f26 RS |
3701 | { |
3702 | /* Convert (a != 0) || (b != 0) into (a | b) != 0. */ | |
3703 | if (code == TRUTH_OR_EXPR | |
3704 | && lcode == NE_EXPR && integer_zerop (lr_arg) | |
3705 | && rcode == NE_EXPR && integer_zerop (rr_arg) | |
3706 | && TREE_TYPE (ll_arg) == TREE_TYPE (rl_arg)) | |
3707 | return build (NE_EXPR, truth_type, | |
3708 | build (BIT_IOR_EXPR, TREE_TYPE (ll_arg), | |
3709 | ll_arg, rl_arg), | |
3710 | integer_zero_node); | |
3711 | ||
3712 | /* Convert (a == 0) && (b == 0) into (a | b) == 0. */ | |
3713 | if (code == TRUTH_AND_EXPR | |
3714 | && lcode == EQ_EXPR && integer_zerop (lr_arg) | |
3715 | && rcode == EQ_EXPR && integer_zerop (rr_arg) | |
3716 | && TREE_TYPE (ll_arg) == TREE_TYPE (rl_arg)) | |
3717 | return build (EQ_EXPR, truth_type, | |
3718 | build (BIT_IOR_EXPR, TREE_TYPE (ll_arg), | |
3719 | ll_arg, rl_arg), | |
3720 | integer_zero_node); | |
3721 | ||
3722 | return build (code, truth_type, lhs, rhs); | |
3723 | } | |
b2215d83 | 3724 | |
ef659ec0 TW |
3725 | /* See if the comparisons can be merged. Then get all the parameters for |
3726 | each side. */ | |
3727 | ||
6d716ca8 | 3728 | if ((lcode != EQ_EXPR && lcode != NE_EXPR) |
ef659ec0 | 3729 | || (rcode != EQ_EXPR && rcode != NE_EXPR)) |
6d716ca8 RS |
3730 | return 0; |
3731 | ||
b2215d83 TW |
3732 | volatilep = 0; |
3733 | ll_inner = decode_field_reference (ll_arg, | |
6d716ca8 | 3734 | &ll_bitsize, &ll_bitpos, &ll_mode, |
d4453ee5 RK |
3735 | &ll_unsignedp, &volatilep, &ll_mask, |
3736 | &ll_and_mask); | |
b2215d83 | 3737 | lr_inner = decode_field_reference (lr_arg, |
6d716ca8 | 3738 | &lr_bitsize, &lr_bitpos, &lr_mode, |
d4453ee5 RK |
3739 | &lr_unsignedp, &volatilep, &lr_mask, |
3740 | &lr_and_mask); | |
b2215d83 | 3741 | rl_inner = decode_field_reference (rl_arg, |
6d716ca8 | 3742 | &rl_bitsize, &rl_bitpos, &rl_mode, |
d4453ee5 RK |
3743 | &rl_unsignedp, &volatilep, &rl_mask, |
3744 | &rl_and_mask); | |
b2215d83 | 3745 | rr_inner = decode_field_reference (rr_arg, |
6d716ca8 | 3746 | &rr_bitsize, &rr_bitpos, &rr_mode, |
d4453ee5 RK |
3747 | &rr_unsignedp, &volatilep, &rr_mask, |
3748 | &rr_and_mask); | |
6d716ca8 RS |
3749 | |
3750 | /* It must be true that the inner operation on the lhs of each | |
3751 | comparison must be the same if we are to be able to do anything. | |
3752 | Then see if we have constants. If not, the same must be true for | |
3753 | the rhs's. */ | |
3754 | if (volatilep || ll_inner == 0 || rl_inner == 0 | |
3755 | || ! operand_equal_p (ll_inner, rl_inner, 0)) | |
3756 | return 0; | |
3757 | ||
b2215d83 TW |
3758 | if (TREE_CODE (lr_arg) == INTEGER_CST |
3759 | && TREE_CODE (rr_arg) == INTEGER_CST) | |
3760 | l_const = lr_arg, r_const = rr_arg; | |
6d716ca8 RS |
3761 | else if (lr_inner == 0 || rr_inner == 0 |
3762 | || ! operand_equal_p (lr_inner, rr_inner, 0)) | |
3763 | return 0; | |
b2215d83 TW |
3764 | else |
3765 | l_const = r_const = 0; | |
6d716ca8 RS |
3766 | |
3767 | /* If either comparison code is not correct for our logical operation, | |
3768 | fail. However, we can convert a one-bit comparison against zero into | |
3769 | the opposite comparison against that bit being set in the field. */ | |
b2215d83 | 3770 | |
9c0ae98b | 3771 | wanted_code = (code == TRUTH_AND_EXPR ? EQ_EXPR : NE_EXPR); |
6d716ca8 RS |
3772 | if (lcode != wanted_code) |
3773 | { | |
3774 | if (l_const && integer_zerop (l_const) && integer_pow2p (ll_mask)) | |
5a6b3365 | 3775 | { |
2bd21a02 AS |
3776 | /* Make the left operand unsigned, since we are only interested |
3777 | in the value of one bit. Otherwise we are doing the wrong | |
3778 | thing below. */ | |
3779 | ll_unsignedp = 1; | |
71a874cd | 3780 | l_const = ll_mask; |
5a6b3365 | 3781 | } |
6d716ca8 RS |
3782 | else |
3783 | return 0; | |
3784 | } | |
3785 | ||
71a874cd | 3786 | /* This is analogous to the code for l_const above. */ |
6d716ca8 RS |
3787 | if (rcode != wanted_code) |
3788 | { | |
3789 | if (r_const && integer_zerop (r_const) && integer_pow2p (rl_mask)) | |
5a6b3365 | 3790 | { |
2bd21a02 | 3791 | rl_unsignedp = 1; |
71a874cd | 3792 | r_const = rl_mask; |
5a6b3365 | 3793 | } |
6d716ca8 RS |
3794 | else |
3795 | return 0; | |
3796 | } | |
3797 | ||
57ce46bb TT |
3798 | /* After this point all optimizations will generate bit-field |
3799 | references, which we might not want. */ | |
3800 | if (! (*lang_hooks.can_use_bit_fields_p) ()) | |
3801 | return 0; | |
3802 | ||
6d716ca8 RS |
3803 | /* See if we can find a mode that contains both fields being compared on |
3804 | the left. If we can't, fail. Otherwise, update all constants and masks | |
3805 | to be relative to a field of that size. */ | |
3806 | first_bit = MIN (ll_bitpos, rl_bitpos); | |
3807 | end_bit = MAX (ll_bitpos + ll_bitsize, rl_bitpos + rl_bitsize); | |
3808 | lnmode = get_best_mode (end_bit - first_bit, first_bit, | |
3809 | TYPE_ALIGN (TREE_TYPE (ll_inner)), word_mode, | |
3810 | volatilep); | |
3811 | if (lnmode == VOIDmode) | |
3812 | return 0; | |
3813 | ||
3814 | lnbitsize = GET_MODE_BITSIZE (lnmode); | |
3815 | lnbitpos = first_bit & ~ (lnbitsize - 1); | |
b0c48229 | 3816 | lntype = (*lang_hooks.types.type_for_size) (lnbitsize, 1); |
6d716ca8 RS |
3817 | xll_bitpos = ll_bitpos - lnbitpos, xrl_bitpos = rl_bitpos - lnbitpos; |
3818 | ||
f76b9db2 ILT |
3819 | if (BYTES_BIG_ENDIAN) |
3820 | { | |
3821 | xll_bitpos = lnbitsize - xll_bitpos - ll_bitsize; | |
3822 | xrl_bitpos = lnbitsize - xrl_bitpos - rl_bitsize; | |
3823 | } | |
6d716ca8 | 3824 | |
bd910dcf | 3825 | ll_mask = const_binop (LSHIFT_EXPR, convert (lntype, ll_mask), |
91d33e36 | 3826 | size_int (xll_bitpos), 0); |
bd910dcf | 3827 | rl_mask = const_binop (LSHIFT_EXPR, convert (lntype, rl_mask), |
91d33e36 | 3828 | size_int (xrl_bitpos), 0); |
6d716ca8 | 3829 | |
6d716ca8 RS |
3830 | if (l_const) |
3831 | { | |
bd910dcf | 3832 | l_const = convert (lntype, l_const); |
b6cc0a72 | 3833 | l_const = unextend (l_const, ll_bitsize, ll_unsignedp, ll_and_mask); |
02103577 RK |
3834 | l_const = const_binop (LSHIFT_EXPR, l_const, size_int (xll_bitpos), 0); |
3835 | if (! integer_zerop (const_binop (BIT_AND_EXPR, l_const, | |
3836 | fold (build1 (BIT_NOT_EXPR, | |
bd910dcf | 3837 | lntype, ll_mask)), |
02103577 RK |
3838 | 0))) |
3839 | { | |
ab87f8c8 | 3840 | warning ("comparison is always %d", wanted_code == NE_EXPR); |
b6cc0a72 | 3841 | |
02103577 RK |
3842 | return convert (truth_type, |
3843 | wanted_code == NE_EXPR | |
3844 | ? integer_one_node : integer_zero_node); | |
3845 | } | |
6d716ca8 RS |
3846 | } |
3847 | if (r_const) | |
3848 | { | |
bd910dcf | 3849 | r_const = convert (lntype, r_const); |
d4453ee5 | 3850 | r_const = unextend (r_const, rl_bitsize, rl_unsignedp, rl_and_mask); |
02103577 RK |
3851 | r_const = const_binop (LSHIFT_EXPR, r_const, size_int (xrl_bitpos), 0); |
3852 | if (! integer_zerop (const_binop (BIT_AND_EXPR, r_const, | |
3853 | fold (build1 (BIT_NOT_EXPR, | |
bd910dcf | 3854 | lntype, rl_mask)), |
02103577 RK |
3855 | 0))) |
3856 | { | |
ab87f8c8 JL |
3857 | warning ("comparison is always %d", wanted_code == NE_EXPR); |
3858 | ||
02103577 RK |
3859 | return convert (truth_type, |
3860 | wanted_code == NE_EXPR | |
3861 | ? integer_one_node : integer_zero_node); | |
3862 | } | |
6d716ca8 RS |
3863 | } |
3864 | ||
3865 | /* If the right sides are not constant, do the same for it. Also, | |
3866 | disallow this optimization if a size or signedness mismatch occurs | |
3867 | between the left and right sides. */ | |
3868 | if (l_const == 0) | |
3869 | { | |
3870 | if (ll_bitsize != lr_bitsize || rl_bitsize != rr_bitsize | |
e6a28f26 RS |
3871 | || ll_unsignedp != lr_unsignedp || rl_unsignedp != rr_unsignedp |
3872 | /* Make sure the two fields on the right | |
3873 | correspond to the left without being swapped. */ | |
3874 | || ll_bitpos - rl_bitpos != lr_bitpos - rr_bitpos) | |
6d716ca8 RS |
3875 | return 0; |
3876 | ||
3877 | first_bit = MIN (lr_bitpos, rr_bitpos); | |
3878 | end_bit = MAX (lr_bitpos + lr_bitsize, rr_bitpos + rr_bitsize); | |
3879 | rnmode = get_best_mode (end_bit - first_bit, first_bit, | |
3880 | TYPE_ALIGN (TREE_TYPE (lr_inner)), word_mode, | |
3881 | volatilep); | |
3882 | if (rnmode == VOIDmode) | |
3883 | return 0; | |
3884 | ||
3885 | rnbitsize = GET_MODE_BITSIZE (rnmode); | |
3886 | rnbitpos = first_bit & ~ (rnbitsize - 1); | |
b0c48229 | 3887 | rntype = (*lang_hooks.types.type_for_size) (rnbitsize, 1); |
6d716ca8 RS |
3888 | xlr_bitpos = lr_bitpos - rnbitpos, xrr_bitpos = rr_bitpos - rnbitpos; |
3889 | ||
f76b9db2 ILT |
3890 | if (BYTES_BIG_ENDIAN) |
3891 | { | |
3892 | xlr_bitpos = rnbitsize - xlr_bitpos - lr_bitsize; | |
3893 | xrr_bitpos = rnbitsize - xrr_bitpos - rr_bitsize; | |
3894 | } | |
6d716ca8 | 3895 | |
bd910dcf | 3896 | lr_mask = const_binop (LSHIFT_EXPR, convert (rntype, lr_mask), |
91d33e36 | 3897 | size_int (xlr_bitpos), 0); |
bd910dcf | 3898 | rr_mask = const_binop (LSHIFT_EXPR, convert (rntype, rr_mask), |
91d33e36 | 3899 | size_int (xrr_bitpos), 0); |
6d716ca8 RS |
3900 | |
3901 | /* Make a mask that corresponds to both fields being compared. | |
11a86c56 CH |
3902 | Do this for both items being compared. If the operands are the |
3903 | same size and the bits being compared are in the same position | |
3904 | then we can do this by masking both and comparing the masked | |
3905 | results. */ | |
91d33e36 RS |
3906 | ll_mask = const_binop (BIT_IOR_EXPR, ll_mask, rl_mask, 0); |
3907 | lr_mask = const_binop (BIT_IOR_EXPR, lr_mask, rr_mask, 0); | |
11a86c56 | 3908 | if (lnbitsize == rnbitsize && xll_bitpos == xlr_bitpos) |
6d716ca8 | 3909 | { |
bd910dcf | 3910 | lhs = make_bit_field_ref (ll_inner, lntype, lnbitsize, lnbitpos, |
6d716ca8 | 3911 | ll_unsignedp || rl_unsignedp); |
11a86c56 CH |
3912 | if (! all_ones_mask_p (ll_mask, lnbitsize)) |
3913 | lhs = build (BIT_AND_EXPR, lntype, lhs, ll_mask); | |
3914 | ||
bd910dcf | 3915 | rhs = make_bit_field_ref (lr_inner, rntype, rnbitsize, rnbitpos, |
6d716ca8 | 3916 | lr_unsignedp || rr_unsignedp); |
11a86c56 CH |
3917 | if (! all_ones_mask_p (lr_mask, rnbitsize)) |
3918 | rhs = build (BIT_AND_EXPR, rntype, rhs, lr_mask); | |
3919 | ||
6d716ca8 RS |
3920 | return build (wanted_code, truth_type, lhs, rhs); |
3921 | } | |
3922 | ||
3923 | /* There is still another way we can do something: If both pairs of | |
3924 | fields being compared are adjacent, we may be able to make a wider | |
97ea7176 CH |
3925 | field containing them both. |
3926 | ||
3927 | Note that we still must mask the lhs/rhs expressions. Furthermore, | |
b6cc0a72 | 3928 | the mask must be shifted to account for the shift done by |
97ea7176 | 3929 | make_bit_field_ref. */ |
6d716ca8 RS |
3930 | if ((ll_bitsize + ll_bitpos == rl_bitpos |
3931 | && lr_bitsize + lr_bitpos == rr_bitpos) | |
3932 | || (ll_bitpos == rl_bitpos + rl_bitsize | |
3933 | && lr_bitpos == rr_bitpos + rr_bitsize)) | |
97ea7176 | 3934 | { |
bd910dcf CH |
3935 | tree type; |
3936 | ||
3937 | lhs = make_bit_field_ref (ll_inner, lntype, ll_bitsize + rl_bitsize, | |
97ea7176 | 3938 | MIN (ll_bitpos, rl_bitpos), ll_unsignedp); |
bd910dcf CH |
3939 | rhs = make_bit_field_ref (lr_inner, rntype, lr_bitsize + rr_bitsize, |
3940 | MIN (lr_bitpos, rr_bitpos), lr_unsignedp); | |
3941 | ||
97ea7176 CH |
3942 | ll_mask = const_binop (RSHIFT_EXPR, ll_mask, |
3943 | size_int (MIN (xll_bitpos, xrl_bitpos)), 0); | |
bd910dcf CH |
3944 | lr_mask = const_binop (RSHIFT_EXPR, lr_mask, |
3945 | size_int (MIN (xlr_bitpos, xrr_bitpos)), 0); | |
3946 | ||
3947 | /* Convert to the smaller type before masking out unwanted bits. */ | |
3948 | type = lntype; | |
3949 | if (lntype != rntype) | |
3950 | { | |
3951 | if (lnbitsize > rnbitsize) | |
3952 | { | |
3953 | lhs = convert (rntype, lhs); | |
3954 | ll_mask = convert (rntype, ll_mask); | |
3955 | type = rntype; | |
3956 | } | |
3957 | else if (lnbitsize < rnbitsize) | |
3958 | { | |
3959 | rhs = convert (lntype, rhs); | |
3960 | lr_mask = convert (lntype, lr_mask); | |
3961 | type = lntype; | |
3962 | } | |
3963 | } | |
3964 | ||
97ea7176 CH |
3965 | if (! all_ones_mask_p (ll_mask, ll_bitsize + rl_bitsize)) |
3966 | lhs = build (BIT_AND_EXPR, type, lhs, ll_mask); | |
3967 | ||
97ea7176 CH |
3968 | if (! all_ones_mask_p (lr_mask, lr_bitsize + rr_bitsize)) |
3969 | rhs = build (BIT_AND_EXPR, type, rhs, lr_mask); | |
3970 | ||
3971 | return build (wanted_code, truth_type, lhs, rhs); | |
3972 | } | |
6d716ca8 RS |
3973 | |
3974 | return 0; | |
3975 | } | |
3976 | ||
3977 | /* Handle the case of comparisons with constants. If there is something in | |
3978 | common between the masks, those bits of the constants must be the same. | |
3979 | If not, the condition is always false. Test for this to avoid generating | |
3980 | incorrect code below. */ | |
91d33e36 | 3981 | result = const_binop (BIT_AND_EXPR, ll_mask, rl_mask, 0); |
6d716ca8 | 3982 | if (! integer_zerop (result) |
91d33e36 RS |
3983 | && simple_cst_equal (const_binop (BIT_AND_EXPR, result, l_const, 0), |
3984 | const_binop (BIT_AND_EXPR, result, r_const, 0)) != 1) | |
6d716ca8 RS |
3985 | { |
3986 | if (wanted_code == NE_EXPR) | |
3987 | { | |
3988 | warning ("`or' of unmatched not-equal tests is always 1"); | |
3989 | return convert (truth_type, integer_one_node); | |
3990 | } | |
3991 | else | |
3992 | { | |
ab87f8c8 | 3993 | warning ("`and' of mutually exclusive equal-tests is always 0"); |
6d716ca8 RS |
3994 | return convert (truth_type, integer_zero_node); |
3995 | } | |
3996 | } | |
3997 | ||
3998 | /* Construct the expression we will return. First get the component | |
3999 | reference we will make. Unless the mask is all ones the width of | |
4000 | that field, perform the mask operation. Then compare with the | |
4001 | merged constant. */ | |
bd910dcf | 4002 | result = make_bit_field_ref (ll_inner, lntype, lnbitsize, lnbitpos, |
6d716ca8 RS |
4003 | ll_unsignedp || rl_unsignedp); |
4004 | ||
91d33e36 | 4005 | ll_mask = const_binop (BIT_IOR_EXPR, ll_mask, rl_mask, 0); |
6d716ca8 | 4006 | if (! all_ones_mask_p (ll_mask, lnbitsize)) |
bd910dcf | 4007 | result = build (BIT_AND_EXPR, lntype, result, ll_mask); |
6d716ca8 RS |
4008 | |
4009 | return build (wanted_code, truth_type, result, | |
91d33e36 | 4010 | const_binop (BIT_IOR_EXPR, l_const, r_const, 0)); |
6d716ca8 RS |
4011 | } |
4012 | \f | |
b6cc0a72 | 4013 | /* Optimize T, which is a comparison of a MIN_EXPR or MAX_EXPR with a |
14a774a9 RK |
4014 | constant. */ |
4015 | ||
4016 | static tree | |
fa8db1f7 | 4017 | optimize_minmax_comparison (tree t) |
14a774a9 RK |
4018 | { |
4019 | tree type = TREE_TYPE (t); | |
4020 | tree arg0 = TREE_OPERAND (t, 0); | |
4021 | enum tree_code op_code; | |
4022 | tree comp_const = TREE_OPERAND (t, 1); | |
4023 | tree minmax_const; | |
4024 | int consts_equal, consts_lt; | |
4025 | tree inner; | |
4026 | ||
4027 | STRIP_SIGN_NOPS (arg0); | |
4028 | ||
4029 | op_code = TREE_CODE (arg0); | |
4030 | minmax_const = TREE_OPERAND (arg0, 1); | |
4031 | consts_equal = tree_int_cst_equal (minmax_const, comp_const); | |
4032 | consts_lt = tree_int_cst_lt (minmax_const, comp_const); | |
4033 | inner = TREE_OPERAND (arg0, 0); | |
4034 | ||
4035 | /* If something does not permit us to optimize, return the original tree. */ | |
4036 | if ((op_code != MIN_EXPR && op_code != MAX_EXPR) | |
4037 | || TREE_CODE (comp_const) != INTEGER_CST | |
4038 | || TREE_CONSTANT_OVERFLOW (comp_const) | |
4039 | || TREE_CODE (minmax_const) != INTEGER_CST | |
4040 | || TREE_CONSTANT_OVERFLOW (minmax_const)) | |
4041 | return t; | |
4042 | ||
4043 | /* Now handle all the various comparison codes. We only handle EQ_EXPR | |
4044 | and GT_EXPR, doing the rest with recursive calls using logical | |
4045 | simplifications. */ | |
4046 | switch (TREE_CODE (t)) | |
4047 | { | |
4048 | case NE_EXPR: case LT_EXPR: case LE_EXPR: | |
4049 | return | |
4050 | invert_truthvalue (optimize_minmax_comparison (invert_truthvalue (t))); | |
4051 | ||
4052 | case GE_EXPR: | |
4053 | return | |
4054 | fold (build (TRUTH_ORIF_EXPR, type, | |
4055 | optimize_minmax_comparison | |
4056 | (build (EQ_EXPR, type, arg0, comp_const)), | |
4057 | optimize_minmax_comparison | |
4058 | (build (GT_EXPR, type, arg0, comp_const)))); | |
4059 | ||
4060 | case EQ_EXPR: | |
4061 | if (op_code == MAX_EXPR && consts_equal) | |
4062 | /* MAX (X, 0) == 0 -> X <= 0 */ | |
4063 | return fold (build (LE_EXPR, type, inner, comp_const)); | |
4064 | ||
4065 | else if (op_code == MAX_EXPR && consts_lt) | |
4066 | /* MAX (X, 0) == 5 -> X == 5 */ | |
4067 | return fold (build (EQ_EXPR, type, inner, comp_const)); | |
4068 | ||
4069 | else if (op_code == MAX_EXPR) | |
4070 | /* MAX (X, 0) == -1 -> false */ | |
4071 | return omit_one_operand (type, integer_zero_node, inner); | |
4072 | ||
4073 | else if (consts_equal) | |
4074 | /* MIN (X, 0) == 0 -> X >= 0 */ | |
4075 | return fold (build (GE_EXPR, type, inner, comp_const)); | |
4076 | ||
4077 | else if (consts_lt) | |
4078 | /* MIN (X, 0) == 5 -> false */ | |
4079 | return omit_one_operand (type, integer_zero_node, inner); | |
4080 | ||
4081 | else | |
4082 | /* MIN (X, 0) == -1 -> X == -1 */ | |
4083 | return fold (build (EQ_EXPR, type, inner, comp_const)); | |
4084 | ||
4085 | case GT_EXPR: | |
4086 | if (op_code == MAX_EXPR && (consts_equal || consts_lt)) | |
4087 | /* MAX (X, 0) > 0 -> X > 0 | |
4088 | MAX (X, 0) > 5 -> X > 5 */ | |
4089 | return fold (build (GT_EXPR, type, inner, comp_const)); | |
4090 | ||
4091 | else if (op_code == MAX_EXPR) | |
4092 | /* MAX (X, 0) > -1 -> true */ | |
4093 | return omit_one_operand (type, integer_one_node, inner); | |
4094 | ||
4095 | else if (op_code == MIN_EXPR && (consts_equal || consts_lt)) | |
4096 | /* MIN (X, 0) > 0 -> false | |
4097 | MIN (X, 0) > 5 -> false */ | |
4098 | return omit_one_operand (type, integer_zero_node, inner); | |
4099 | ||
4100 | else | |
4101 | /* MIN (X, 0) > -1 -> X > -1 */ | |
4102 | return fold (build (GT_EXPR, type, inner, comp_const)); | |
4103 | ||
4104 | default: | |
4105 | return t; | |
4106 | } | |
4107 | } | |
4108 | \f | |
1baa375f RK |
4109 | /* T is an integer expression that is being multiplied, divided, or taken a |
4110 | modulus (CODE says which and what kind of divide or modulus) by a | |
4111 | constant C. See if we can eliminate that operation by folding it with | |
4112 | other operations already in T. WIDE_TYPE, if non-null, is a type that | |
4113 | should be used for the computation if wider than our type. | |
4114 | ||
cff27795 EB |
4115 | For example, if we are dividing (X * 8) + (Y * 16) by 4, we can return |
4116 | (X * 2) + (Y * 4). We must, however, be assured that either the original | |
8e1ca098 RH |
4117 | expression would not overflow or that overflow is undefined for the type |
4118 | in the language in question. | |
4119 | ||
4120 | We also canonicalize (X + 7) * 4 into X * 4 + 28 in the hope that either | |
4121 | the machine has a multiply-accumulate insn or that this is part of an | |
4122 | addressing calculation. | |
1baa375f RK |
4123 | |
4124 | If we return a non-null expression, it is an equivalent form of the | |
4125 | original computation, but need not be in the original type. */ | |
4126 | ||
4127 | static tree | |
fa8db1f7 | 4128 | extract_muldiv (tree t, tree c, enum tree_code code, tree wide_type) |
cdd4b0d4 AB |
4129 | { |
4130 | /* To avoid exponential search depth, refuse to allow recursion past | |
4131 | three levels. Beyond that (1) it's highly unlikely that we'll find | |
4132 | something interesting and (2) we've probably processed it before | |
4133 | when we built the inner expression. */ | |
4134 | ||
4135 | static int depth; | |
4136 | tree ret; | |
4137 | ||
4138 | if (depth > 3) | |
4139 | return NULL; | |
4140 | ||
4141 | depth++; | |
4142 | ret = extract_muldiv_1 (t, c, code, wide_type); | |
4143 | depth--; | |
4144 | ||
4145 | return ret; | |
4146 | } | |
4147 | ||
4148 | static tree | |
fa8db1f7 | 4149 | extract_muldiv_1 (tree t, tree c, enum tree_code code, tree wide_type) |
1baa375f RK |
4150 | { |
4151 | tree type = TREE_TYPE (t); | |
4152 | enum tree_code tcode = TREE_CODE (t); | |
b6cc0a72 | 4153 | tree ctype = (wide_type != 0 && (GET_MODE_SIZE (TYPE_MODE (wide_type)) |
1baa375f RK |
4154 | > GET_MODE_SIZE (TYPE_MODE (type))) |
4155 | ? wide_type : type); | |
4156 | tree t1, t2; | |
4157 | int same_p = tcode == code; | |
9d0878fd | 4158 | tree op0 = NULL_TREE, op1 = NULL_TREE; |
1baa375f RK |
4159 | |
4160 | /* Don't deal with constants of zero here; they confuse the code below. */ | |
4161 | if (integer_zerop (c)) | |
8e1ca098 | 4162 | return NULL_TREE; |
1baa375f RK |
4163 | |
4164 | if (TREE_CODE_CLASS (tcode) == '1') | |
4165 | op0 = TREE_OPERAND (t, 0); | |
4166 | ||
4167 | if (TREE_CODE_CLASS (tcode) == '2') | |
4168 | op0 = TREE_OPERAND (t, 0), op1 = TREE_OPERAND (t, 1); | |
4169 | ||
4170 | /* Note that we need not handle conditional operations here since fold | |
4171 | already handles those cases. So just do arithmetic here. */ | |
4172 | switch (tcode) | |
4173 | { | |
4174 | case INTEGER_CST: | |
4175 | /* For a constant, we can always simplify if we are a multiply | |
4176 | or (for divide and modulus) if it is a multiple of our constant. */ | |
4177 | if (code == MULT_EXPR | |
4178 | || integer_zerop (const_binop (TRUNC_MOD_EXPR, t, c, 0))) | |
4179 | return const_binop (code, convert (ctype, t), convert (ctype, c), 0); | |
4180 | break; | |
4181 | ||
4182 | case CONVERT_EXPR: case NON_LVALUE_EXPR: case NOP_EXPR: | |
43e4a9d8 | 4183 | /* If op0 is an expression ... */ |
eff9c80d RH |
4184 | if ((TREE_CODE_CLASS (TREE_CODE (op0)) == '<' |
4185 | || TREE_CODE_CLASS (TREE_CODE (op0)) == '1' | |
4186 | || TREE_CODE_CLASS (TREE_CODE (op0)) == '2' | |
4187 | || TREE_CODE_CLASS (TREE_CODE (op0)) == 'e') | |
43e4a9d8 EB |
4188 | /* ... and is unsigned, and its type is smaller than ctype, |
4189 | then we cannot pass through as widening. */ | |
4190 | && ((TREE_UNSIGNED (TREE_TYPE (op0)) | |
4191 | && ! (TREE_CODE (TREE_TYPE (op0)) == INTEGER_TYPE | |
4192 | && TYPE_IS_SIZETYPE (TREE_TYPE (op0))) | |
4193 | && (GET_MODE_SIZE (TYPE_MODE (ctype)) | |
4194 | > GET_MODE_SIZE (TYPE_MODE (TREE_TYPE (op0))))) | |
4195 | /* ... or its type is larger than ctype, | |
4196 | then we cannot pass through this truncation. */ | |
4197 | || (GET_MODE_SIZE (TYPE_MODE (ctype)) | |
068d2c9d MM |
4198 | < GET_MODE_SIZE (TYPE_MODE (TREE_TYPE (op0)))) |
4199 | /* ... or signedness changes for division or modulus, | |
4200 | then we cannot pass through this conversion. */ | |
4201 | || (code != MULT_EXPR | |
4202 | && (TREE_UNSIGNED (ctype) | |
4203 | != TREE_UNSIGNED (TREE_TYPE (op0)))))) | |
eff9c80d RH |
4204 | break; |
4205 | ||
1baa375f | 4206 | /* Pass the constant down and see if we can make a simplification. If |
59adecfa RK |
4207 | we can, replace this expression with the inner simplification for |
4208 | possible later conversion to our or some other type. */ | |
3cd58fd7 OH |
4209 | if ((t2 = convert (TREE_TYPE (op0), c)) != 0 |
4210 | && TREE_CODE (t2) == INTEGER_CST | |
4211 | && ! TREE_CONSTANT_OVERFLOW (t2) | |
4212 | && (0 != (t1 = extract_muldiv (op0, t2, code, | |
4213 | code == MULT_EXPR | |
4214 | ? ctype : NULL_TREE)))) | |
1baa375f RK |
4215 | return t1; |
4216 | break; | |
4217 | ||
4218 | case NEGATE_EXPR: case ABS_EXPR: | |
4219 | if ((t1 = extract_muldiv (op0, c, code, wide_type)) != 0) | |
4220 | return fold (build1 (tcode, ctype, convert (ctype, t1))); | |
4221 | break; | |
4222 | ||
4223 | case MIN_EXPR: case MAX_EXPR: | |
13393c8a JW |
4224 | /* If widening the type changes the signedness, then we can't perform |
4225 | this optimization as that changes the result. */ | |
eff9c80d | 4226 | if (TREE_UNSIGNED (ctype) != TREE_UNSIGNED (type)) |
13393c8a JW |
4227 | break; |
4228 | ||
1baa375f RK |
4229 | /* MIN (a, b) / 5 -> MIN (a / 5, b / 5) */ |
4230 | if ((t1 = extract_muldiv (op0, c, code, wide_type)) != 0 | |
4231 | && (t2 = extract_muldiv (op1, c, code, wide_type)) != 0) | |
59adecfa RK |
4232 | { |
4233 | if (tree_int_cst_sgn (c) < 0) | |
4234 | tcode = (tcode == MIN_EXPR ? MAX_EXPR : MIN_EXPR); | |
4235 | ||
4236 | return fold (build (tcode, ctype, convert (ctype, t1), | |
4237 | convert (ctype, t2))); | |
4238 | } | |
1baa375f RK |
4239 | break; |
4240 | ||
4241 | case WITH_RECORD_EXPR: | |
4242 | if ((t1 = extract_muldiv (TREE_OPERAND (t, 0), c, code, wide_type)) != 0) | |
4243 | return build (WITH_RECORD_EXPR, TREE_TYPE (t1), t1, | |
4244 | TREE_OPERAND (t, 1)); | |
4245 | break; | |
4246 | ||
1baa375f RK |
4247 | case LSHIFT_EXPR: case RSHIFT_EXPR: |
4248 | /* If the second operand is constant, this is a multiplication | |
4249 | or floor division, by a power of two, so we can treat it that | |
4250 | way unless the multiplier or divisor overflows. */ | |
4251 | if (TREE_CODE (op1) == INTEGER_CST | |
d08230fe NC |
4252 | /* const_binop may not detect overflow correctly, |
4253 | so check for it explicitly here. */ | |
4254 | && TYPE_PRECISION (TREE_TYPE (size_one_node)) > TREE_INT_CST_LOW (op1) | |
4255 | && TREE_INT_CST_HIGH (op1) == 0 | |
1baa375f RK |
4256 | && 0 != (t1 = convert (ctype, |
4257 | const_binop (LSHIFT_EXPR, size_one_node, | |
4258 | op1, 0))) | |
4259 | && ! TREE_OVERFLOW (t1)) | |
4260 | return extract_muldiv (build (tcode == LSHIFT_EXPR | |
4261 | ? MULT_EXPR : FLOOR_DIV_EXPR, | |
4262 | ctype, convert (ctype, op0), t1), | |
4263 | c, code, wide_type); | |
4264 | break; | |
4265 | ||
4266 | case PLUS_EXPR: case MINUS_EXPR: | |
4267 | /* See if we can eliminate the operation on both sides. If we can, we | |
4268 | can return a new PLUS or MINUS. If we can't, the only remaining | |
4269 | cases where we can do anything are if the second operand is a | |
4270 | constant. */ | |
4271 | t1 = extract_muldiv (op0, c, code, wide_type); | |
4272 | t2 = extract_muldiv (op1, c, code, wide_type); | |
fba2c0cd JJ |
4273 | if (t1 != 0 && t2 != 0 |
4274 | && (code == MULT_EXPR | |
b77f3744 CE |
4275 | /* If not multiplication, we can only do this if both operands |
4276 | are divisible by c. */ | |
4277 | || (multiple_of_p (ctype, op0, c) | |
4278 | && multiple_of_p (ctype, op1, c)))) | |
1baa375f RK |
4279 | return fold (build (tcode, ctype, convert (ctype, t1), |
4280 | convert (ctype, t2))); | |
1baa375f | 4281 | |
59adecfa RK |
4282 | /* If this was a subtraction, negate OP1 and set it to be an addition. |
4283 | This simplifies the logic below. */ | |
4284 | if (tcode == MINUS_EXPR) | |
4285 | tcode = PLUS_EXPR, op1 = negate_expr (op1); | |
4286 | ||
f9011d04 RK |
4287 | if (TREE_CODE (op1) != INTEGER_CST) |
4288 | break; | |
4289 | ||
59adecfa RK |
4290 | /* If either OP1 or C are negative, this optimization is not safe for |
4291 | some of the division and remainder types while for others we need | |
4292 | to change the code. */ | |
4293 | if (tree_int_cst_sgn (op1) < 0 || tree_int_cst_sgn (c) < 0) | |
4294 | { | |
4295 | if (code == CEIL_DIV_EXPR) | |
4296 | code = FLOOR_DIV_EXPR; | |
59adecfa RK |
4297 | else if (code == FLOOR_DIV_EXPR) |
4298 | code = CEIL_DIV_EXPR; | |
0629440f RK |
4299 | else if (code != MULT_EXPR |
4300 | && code != CEIL_MOD_EXPR && code != FLOOR_MOD_EXPR) | |
59adecfa RK |
4301 | break; |
4302 | } | |
4303 | ||
12644a9a TM |
4304 | /* If it's a multiply or a division/modulus operation of a multiple |
4305 | of our constant, do the operation and verify it doesn't overflow. */ | |
4306 | if (code == MULT_EXPR | |
4307 | || integer_zerop (const_binop (TRUNC_MOD_EXPR, op1, c, 0))) | |
dd3f0101 KH |
4308 | { |
4309 | op1 = const_binop (code, convert (ctype, op1), convert (ctype, c), 0); | |
4310 | if (op1 == 0 || TREE_OVERFLOW (op1)) | |
4311 | break; | |
4312 | } | |
12644a9a | 4313 | else |
dd3f0101 | 4314 | break; |
59adecfa | 4315 | |
23cdce68 RH |
4316 | /* If we have an unsigned type is not a sizetype, we cannot widen |
4317 | the operation since it will change the result if the original | |
4318 | computation overflowed. */ | |
4319 | if (TREE_UNSIGNED (ctype) | |
7393c642 | 4320 | && ! (TREE_CODE (ctype) == INTEGER_TYPE && TYPE_IS_SIZETYPE (ctype)) |
23cdce68 RH |
4321 | && ctype != type) |
4322 | break; | |
4323 | ||
1baa375f | 4324 | /* If we were able to eliminate our operation from the first side, |
59adecfa RK |
4325 | apply our operation to the second side and reform the PLUS. */ |
4326 | if (t1 != 0 && (TREE_CODE (t1) != code || code == MULT_EXPR)) | |
4327 | return fold (build (tcode, ctype, convert (ctype, t1), op1)); | |
1baa375f RK |
4328 | |
4329 | /* The last case is if we are a multiply. In that case, we can | |
4330 | apply the distributive law to commute the multiply and addition | |
30f7a378 | 4331 | if the multiplication of the constants doesn't overflow. */ |
59adecfa | 4332 | if (code == MULT_EXPR) |
1baa375f RK |
4333 | return fold (build (tcode, ctype, fold (build (code, ctype, |
4334 | convert (ctype, op0), | |
4335 | convert (ctype, c))), | |
59adecfa | 4336 | op1)); |
1baa375f RK |
4337 | |
4338 | break; | |
4339 | ||
4340 | case MULT_EXPR: | |
4341 | /* We have a special case here if we are doing something like | |
4342 | (C * 8) % 4 since we know that's zero. */ | |
4343 | if ((code == TRUNC_MOD_EXPR || code == CEIL_MOD_EXPR | |
4344 | || code == FLOOR_MOD_EXPR || code == ROUND_MOD_EXPR) | |
4345 | && TREE_CODE (TREE_OPERAND (t, 1)) == INTEGER_CST | |
4346 | && integer_zerop (const_binop (TRUNC_MOD_EXPR, op1, c, 0))) | |
4347 | return omit_one_operand (type, integer_zero_node, op0); | |
4348 | ||
30f7a378 | 4349 | /* ... fall through ... */ |
1baa375f RK |
4350 | |
4351 | case TRUNC_DIV_EXPR: case CEIL_DIV_EXPR: case FLOOR_DIV_EXPR: | |
4352 | case ROUND_DIV_EXPR: case EXACT_DIV_EXPR: | |
4353 | /* If we can extract our operation from the LHS, do so and return a | |
4354 | new operation. Likewise for the RHS from a MULT_EXPR. Otherwise, | |
4355 | do something only if the second operand is a constant. */ | |
4356 | if (same_p | |
4357 | && (t1 = extract_muldiv (op0, c, code, wide_type)) != 0) | |
4358 | return fold (build (tcode, ctype, convert (ctype, t1), | |
4359 | convert (ctype, op1))); | |
4360 | else if (tcode == MULT_EXPR && code == MULT_EXPR | |
4361 | && (t1 = extract_muldiv (op1, c, code, wide_type)) != 0) | |
4362 | return fold (build (tcode, ctype, convert (ctype, op0), | |
4363 | convert (ctype, t1))); | |
4364 | else if (TREE_CODE (op1) != INTEGER_CST) | |
4365 | return 0; | |
4366 | ||
4367 | /* If these are the same operation types, we can associate them | |
4368 | assuming no overflow. */ | |
4369 | if (tcode == code | |
4370 | && 0 != (t1 = const_binop (MULT_EXPR, convert (ctype, op1), | |
4371 | convert (ctype, c), 0)) | |
4372 | && ! TREE_OVERFLOW (t1)) | |
4373 | return fold (build (tcode, ctype, convert (ctype, op0), t1)); | |
4374 | ||
4375 | /* If these operations "cancel" each other, we have the main | |
4376 | optimizations of this pass, which occur when either constant is a | |
4377 | multiple of the other, in which case we replace this with either an | |
b6cc0a72 | 4378 | operation or CODE or TCODE. |
8e1ca098 | 4379 | |
f5143c46 | 4380 | If we have an unsigned type that is not a sizetype, we cannot do |
8e1ca098 RH |
4381 | this since it will change the result if the original computation |
4382 | overflowed. */ | |
4383 | if ((! TREE_UNSIGNED (ctype) | |
7393c642 | 4384 | || (TREE_CODE (ctype) == INTEGER_TYPE && TYPE_IS_SIZETYPE (ctype))) |
4fa26a60 | 4385 | && ! flag_wrapv |
8e1ca098 RH |
4386 | && ((code == MULT_EXPR && tcode == EXACT_DIV_EXPR) |
4387 | || (tcode == MULT_EXPR | |
4388 | && code != TRUNC_MOD_EXPR && code != CEIL_MOD_EXPR | |
4389 | && code != FLOOR_MOD_EXPR && code != ROUND_MOD_EXPR))) | |
1baa375f RK |
4390 | { |
4391 | if (integer_zerop (const_binop (TRUNC_MOD_EXPR, op1, c, 0))) | |
4392 | return fold (build (tcode, ctype, convert (ctype, op0), | |
4393 | convert (ctype, | |
4394 | const_binop (TRUNC_DIV_EXPR, | |
4395 | op1, c, 0)))); | |
4396 | else if (integer_zerop (const_binop (TRUNC_MOD_EXPR, c, op1, 0))) | |
4397 | return fold (build (code, ctype, convert (ctype, op0), | |
4398 | convert (ctype, | |
4399 | const_binop (TRUNC_DIV_EXPR, | |
4400 | c, op1, 0)))); | |
4401 | } | |
4402 | break; | |
4403 | ||
4404 | default: | |
4405 | break; | |
4406 | } | |
4407 | ||
4408 | return 0; | |
4409 | } | |
4410 | \f | |
b5f3b6b6 RK |
4411 | /* If T contains a COMPOUND_EXPR which was inserted merely to evaluate |
4412 | S, a SAVE_EXPR, return the expression actually being evaluated. Note | |
4413 | that we may sometimes modify the tree. */ | |
4414 | ||
4415 | static tree | |
fa8db1f7 | 4416 | strip_compound_expr (tree t, tree s) |
b5f3b6b6 | 4417 | { |
b5f3b6b6 RK |
4418 | enum tree_code code = TREE_CODE (t); |
4419 | ||
4420 | /* See if this is the COMPOUND_EXPR we want to eliminate. */ | |
4421 | if (code == COMPOUND_EXPR && TREE_CODE (TREE_OPERAND (t, 0)) == CONVERT_EXPR | |
4422 | && TREE_OPERAND (TREE_OPERAND (t, 0), 0) == s) | |
4423 | return TREE_OPERAND (t, 1); | |
4424 | ||
4425 | /* See if this is a COND_EXPR or a simple arithmetic operator. We | |
4426 | don't bother handling any other types. */ | |
4427 | else if (code == COND_EXPR) | |
4428 | { | |
4429 | TREE_OPERAND (t, 0) = strip_compound_expr (TREE_OPERAND (t, 0), s); | |
4430 | TREE_OPERAND (t, 1) = strip_compound_expr (TREE_OPERAND (t, 1), s); | |
4431 | TREE_OPERAND (t, 2) = strip_compound_expr (TREE_OPERAND (t, 2), s); | |
4432 | } | |
4433 | else if (TREE_CODE_CLASS (code) == '1') | |
4434 | TREE_OPERAND (t, 0) = strip_compound_expr (TREE_OPERAND (t, 0), s); | |
4435 | else if (TREE_CODE_CLASS (code) == '<' | |
4436 | || TREE_CODE_CLASS (code) == '2') | |
4437 | { | |
4438 | TREE_OPERAND (t, 0) = strip_compound_expr (TREE_OPERAND (t, 0), s); | |
4439 | TREE_OPERAND (t, 1) = strip_compound_expr (TREE_OPERAND (t, 1), s); | |
4440 | } | |
4441 | ||
4442 | return t; | |
4443 | } | |
4444 | \f | |
f628873f MM |
4445 | /* Return a node which has the indicated constant VALUE (either 0 or |
4446 | 1), and is of the indicated TYPE. */ | |
4447 | ||
83e0821b | 4448 | static tree |
fa8db1f7 | 4449 | constant_boolean_node (int value, tree type) |
f628873f MM |
4450 | { |
4451 | if (type == integer_type_node) | |
4452 | return value ? integer_one_node : integer_zero_node; | |
4453 | else if (TREE_CODE (type) == BOOLEAN_TYPE) | |
78ef5b89 NB |
4454 | return (*lang_hooks.truthvalue_conversion) (value ? integer_one_node : |
4455 | integer_zero_node); | |
b6cc0a72 | 4456 | else |
f628873f MM |
4457 | { |
4458 | tree t = build_int_2 (value, 0); | |
d4b60170 | 4459 | |
f628873f MM |
4460 | TREE_TYPE (t) = type; |
4461 | return t; | |
4462 | } | |
4463 | } | |
4464 | ||
ab87f8c8 JL |
4465 | /* Utility function for the following routine, to see how complex a nesting of |
4466 | COND_EXPRs can be. EXPR is the expression and LIMIT is a count beyond which | |
4467 | we don't care (to avoid spending too much time on complex expressions.). */ | |
4468 | ||
4469 | static int | |
fa8db1f7 | 4470 | count_cond (tree expr, int lim) |
ab87f8c8 | 4471 | { |
d6edb99e | 4472 | int ctrue, cfalse; |
ab87f8c8 JL |
4473 | |
4474 | if (TREE_CODE (expr) != COND_EXPR) | |
4475 | return 0; | |
4476 | else if (lim <= 0) | |
4477 | return 0; | |
4478 | ||
d6edb99e ZW |
4479 | ctrue = count_cond (TREE_OPERAND (expr, 1), lim - 1); |
4480 | cfalse = count_cond (TREE_OPERAND (expr, 2), lim - 1 - ctrue); | |
4481 | return MIN (lim, 1 + ctrue + cfalse); | |
ab87f8c8 | 4482 | } |
68626d4f | 4483 | |
1f77b5da | 4484 | /* Transform `a + (b ? x : y)' into `b ? (a + x) : (a + y)'. |
68626d4f MM |
4485 | Transform, `a + (x < y)' into `(x < y) ? (a + 1) : (a + 0)'. Here |
4486 | CODE corresponds to the `+', COND to the `(b ? x : y)' or `(x < y)' | |
cc2902df | 4487 | expression, and ARG to `a'. If COND_FIRST_P is nonzero, then the |
68626d4f MM |
4488 | COND is the first argument to CODE; otherwise (as in the example |
4489 | given here), it is the second argument. TYPE is the type of the | |
4490 | original expression. */ | |
4491 | ||
4492 | static tree | |
75040a04 AJ |
4493 | fold_binary_op_with_conditional_arg (enum tree_code code, tree type, |
4494 | tree cond, tree arg, int cond_first_p) | |
68626d4f MM |
4495 | { |
4496 | tree test, true_value, false_value; | |
4497 | tree lhs = NULL_TREE; | |
4498 | tree rhs = NULL_TREE; | |
4499 | /* In the end, we'll produce a COND_EXPR. Both arms of the | |
4500 | conditional expression will be binary operations. The left-hand | |
4501 | side of the expression to be executed if the condition is true | |
4502 | will be pointed to by TRUE_LHS. Similarly, the right-hand side | |
4503 | of the expression to be executed if the condition is true will be | |
d6a7951f | 4504 | pointed to by TRUE_RHS. FALSE_LHS and FALSE_RHS are analogous -- |
68626d4f MM |
4505 | but apply to the expression to be executed if the conditional is |
4506 | false. */ | |
4507 | tree *true_lhs; | |
4508 | tree *true_rhs; | |
4509 | tree *false_lhs; | |
4510 | tree *false_rhs; | |
4511 | /* These are the codes to use for the left-hand side and right-hand | |
4512 | side of the COND_EXPR. Normally, they are the same as CODE. */ | |
4513 | enum tree_code lhs_code = code; | |
4514 | enum tree_code rhs_code = code; | |
4515 | /* And these are the types of the expressions. */ | |
4516 | tree lhs_type = type; | |
4517 | tree rhs_type = type; | |
8fe734a3 | 4518 | int save = 0; |
68626d4f MM |
4519 | |
4520 | if (cond_first_p) | |
4521 | { | |
4522 | true_rhs = false_rhs = &arg; | |
4523 | true_lhs = &true_value; | |
4524 | false_lhs = &false_value; | |
4525 | } | |
4526 | else | |
4527 | { | |
4528 | true_lhs = false_lhs = &arg; | |
4529 | true_rhs = &true_value; | |
4530 | false_rhs = &false_value; | |
4531 | } | |
4532 | ||
4533 | if (TREE_CODE (cond) == COND_EXPR) | |
4534 | { | |
4535 | test = TREE_OPERAND (cond, 0); | |
4536 | true_value = TREE_OPERAND (cond, 1); | |
4537 | false_value = TREE_OPERAND (cond, 2); | |
4538 | /* If this operand throws an expression, then it does not make | |
4539 | sense to try to perform a logical or arithmetic operation | |
4540 | involving it. Instead of building `a + throw 3' for example, | |
4541 | we simply build `a, throw 3'. */ | |
4542 | if (VOID_TYPE_P (TREE_TYPE (true_value))) | |
4543 | { | |
9402f6fb RS |
4544 | if (! cond_first_p) |
4545 | { | |
4546 | lhs_code = COMPOUND_EXPR; | |
4547 | lhs_type = void_type_node; | |
4548 | } | |
4549 | else | |
4550 | lhs = true_value; | |
68626d4f MM |
4551 | } |
4552 | if (VOID_TYPE_P (TREE_TYPE (false_value))) | |
4553 | { | |
9402f6fb RS |
4554 | if (! cond_first_p) |
4555 | { | |
4556 | rhs_code = COMPOUND_EXPR; | |
4557 | rhs_type = void_type_node; | |
4558 | } | |
4559 | else | |
4560 | rhs = false_value; | |
68626d4f MM |
4561 | } |
4562 | } | |
4563 | else | |
4564 | { | |
4565 | tree testtype = TREE_TYPE (cond); | |
4566 | test = cond; | |
4567 | true_value = convert (testtype, integer_one_node); | |
4568 | false_value = convert (testtype, integer_zero_node); | |
4569 | } | |
dd3f0101 | 4570 | |
a9ecacf6 OH |
4571 | /* If ARG is complex we want to make sure we only evaluate it once. Though |
4572 | this is only required if it is volatile, it might be more efficient even | |
4573 | if it is not. However, if we succeed in folding one part to a constant, | |
4574 | we do not need to make this SAVE_EXPR. Since we do this optimization | |
4575 | primarily to see if we do end up with constant and this SAVE_EXPR | |
4576 | interferes with later optimizations, suppressing it when we can is | |
4577 | important. | |
4578 | ||
4579 | If we are not in a function, we can't make a SAVE_EXPR, so don't try to | |
4580 | do so. Don't try to see if the result is a constant if an arm is a | |
4581 | COND_EXPR since we get exponential behavior in that case. */ | |
4582 | ||
4583 | if (saved_expr_p (arg)) | |
8fe734a3 | 4584 | save = 1; |
9402f6fb RS |
4585 | else if (lhs == 0 && rhs == 0 |
4586 | && !TREE_CONSTANT (arg) | |
8fe734a3 NS |
4587 | && (*lang_hooks.decls.global_bindings_p) () == 0 |
4588 | && ((TREE_CODE (arg) != VAR_DECL && TREE_CODE (arg) != PARM_DECL) | |
4589 | || TREE_SIDE_EFFECTS (arg))) | |
68626d4f MM |
4590 | { |
4591 | if (TREE_CODE (true_value) != COND_EXPR) | |
4592 | lhs = fold (build (lhs_code, lhs_type, *true_lhs, *true_rhs)); | |
dd3f0101 | 4593 | |
68626d4f MM |
4594 | if (TREE_CODE (false_value) != COND_EXPR) |
4595 | rhs = fold (build (rhs_code, rhs_type, *false_lhs, *false_rhs)); | |
dd3f0101 | 4596 | |
68626d4f MM |
4597 | if ((lhs == 0 || ! TREE_CONSTANT (lhs)) |
4598 | && (rhs == 0 || !TREE_CONSTANT (rhs))) | |
8fe734a3 NS |
4599 | { |
4600 | arg = save_expr (arg); | |
4601 | lhs = rhs = 0; | |
4602 | save = 1; | |
4603 | } | |
68626d4f | 4604 | } |
dd3f0101 | 4605 | |
68626d4f MM |
4606 | if (lhs == 0) |
4607 | lhs = fold (build (lhs_code, lhs_type, *true_lhs, *true_rhs)); | |
4608 | if (rhs == 0) | |
4609 | rhs = fold (build (rhs_code, rhs_type, *false_lhs, *false_rhs)); | |
dd3f0101 | 4610 | |
68626d4f | 4611 | test = fold (build (COND_EXPR, type, test, lhs, rhs)); |
dd3f0101 | 4612 | |
8fe734a3 | 4613 | if (save) |
68626d4f MM |
4614 | return build (COMPOUND_EXPR, type, |
4615 | convert (void_type_node, arg), | |
4616 | strip_compound_expr (test, arg)); | |
4617 | else | |
4618 | return convert (type, test); | |
4619 | } | |
4620 | ||
ab87f8c8 | 4621 | \f |
71925bc0 RS |
4622 | /* Subroutine of fold() that checks for the addition of +/- 0.0. |
4623 | ||
4624 | If !NEGATE, return true if ADDEND is +/-0.0 and, for all X of type | |
4625 | TYPE, X + ADDEND is the same as X. If NEGATE, return true if X - | |
4626 | ADDEND is the same as X. | |
4627 | ||
cc2902df | 4628 | X + 0 and X - 0 both give X when X is NaN, infinite, or nonzero |
71925bc0 RS |
4629 | and finite. The problematic cases are when X is zero, and its mode |
4630 | has signed zeros. In the case of rounding towards -infinity, | |
4631 | X - 0 is not the same as X because 0 - 0 is -0. In other rounding | |
4632 | modes, X + 0 is not the same as X because -0 + 0 is 0. */ | |
4633 | ||
4634 | static bool | |
fa8db1f7 | 4635 | fold_real_zero_addition_p (tree type, tree addend, int negate) |
71925bc0 RS |
4636 | { |
4637 | if (!real_zerop (addend)) | |
4638 | return false; | |
4639 | ||
3bc400cd RS |
4640 | /* Don't allow the fold with -fsignaling-nans. */ |
4641 | if (HONOR_SNANS (TYPE_MODE (type))) | |
4642 | return false; | |
4643 | ||
71925bc0 RS |
4644 | /* Allow the fold if zeros aren't signed, or their sign isn't important. */ |
4645 | if (!HONOR_SIGNED_ZEROS (TYPE_MODE (type))) | |
4646 | return true; | |
4647 | ||
4648 | /* Treat x + -0 as x - 0 and x - -0 as x + 0. */ | |
4649 | if (TREE_CODE (addend) == REAL_CST | |
4650 | && REAL_VALUE_MINUS_ZERO (TREE_REAL_CST (addend))) | |
4651 | negate = !negate; | |
4652 | ||
4653 | /* The mode has signed zeros, and we have to honor their sign. | |
4654 | In this situation, there is only one case we can return true for. | |
4655 | X - 0 is the same as X unless rounding towards -infinity is | |
4656 | supported. */ | |
4657 | return negate && !HONOR_SIGN_DEPENDENT_ROUNDING (TYPE_MODE (type)); | |
4658 | } | |
4659 | ||
c876997f RS |
4660 | /* Subroutine of fold() that checks comparisons of built-in math |
4661 | functions against real constants. | |
4662 | ||
4663 | FCODE is the DECL_FUNCTION_CODE of the built-in, CODE is the comparison | |
4664 | operator: EQ_EXPR, NE_EXPR, GT_EXPR, LT_EXPR, GE_EXPR or LE_EXPR. TYPE | |
4665 | is the type of the result and ARG0 and ARG1 are the operands of the | |
4666 | comparison. ARG1 must be a TREE_REAL_CST. | |
4667 | ||
4668 | The function returns the constant folded tree if a simplification | |
4669 | can be made, and NULL_TREE otherwise. */ | |
4670 | ||
4671 | static tree | |
75040a04 AJ |
4672 | fold_mathfn_compare (enum built_in_function fcode, enum tree_code code, |
4673 | tree type, tree arg0, tree arg1) | |
c876997f RS |
4674 | { |
4675 | REAL_VALUE_TYPE c; | |
4676 | ||
4677 | if (fcode == BUILT_IN_SQRT | |
4678 | || fcode == BUILT_IN_SQRTF | |
4679 | || fcode == BUILT_IN_SQRTL) | |
4680 | { | |
4681 | tree arg = TREE_VALUE (TREE_OPERAND (arg0, 1)); | |
4682 | enum machine_mode mode = TYPE_MODE (TREE_TYPE (arg0)); | |
4683 | ||
4684 | c = TREE_REAL_CST (arg1); | |
4685 | if (REAL_VALUE_NEGATIVE (c)) | |
4686 | { | |
4687 | /* sqrt(x) < y is always false, if y is negative. */ | |
4688 | if (code == EQ_EXPR || code == LT_EXPR || code == LE_EXPR) | |
4689 | return omit_one_operand (type, | |
4690 | convert (type, integer_zero_node), | |
4691 | arg); | |
4692 | ||
4693 | /* sqrt(x) > y is always true, if y is negative and we | |
4694 | don't care about NaNs, i.e. negative values of x. */ | |
4695 | if (code == NE_EXPR || !HONOR_NANS (mode)) | |
4696 | return omit_one_operand (type, | |
4697 | convert (type, integer_one_node), | |
4698 | arg); | |
4699 | ||
4700 | /* sqrt(x) > y is the same as x >= 0, if y is negative. */ | |
4701 | return fold (build (GE_EXPR, type, arg, | |
4702 | build_real (TREE_TYPE (arg), dconst0))); | |
4703 | } | |
4704 | else if (code == GT_EXPR || code == GE_EXPR) | |
4705 | { | |
4706 | REAL_VALUE_TYPE c2; | |
4707 | ||
4708 | REAL_ARITHMETIC (c2, MULT_EXPR, c, c); | |
4709 | real_convert (&c2, mode, &c2); | |
4710 | ||
4711 | if (REAL_VALUE_ISINF (c2)) | |
4712 | { | |
4713 | /* sqrt(x) > y is x == +Inf, when y is very large. */ | |
4714 | if (HONOR_INFINITIES (mode)) | |
4715 | return fold (build (EQ_EXPR, type, arg, | |
4716 | build_real (TREE_TYPE (arg), c2))); | |
4717 | ||
4718 | /* sqrt(x) > y is always false, when y is very large | |
4719 | and we don't care about infinities. */ | |
4720 | return omit_one_operand (type, | |
4721 | convert (type, integer_zero_node), | |
4722 | arg); | |
4723 | } | |
4724 | ||
4725 | /* sqrt(x) > c is the same as x > c*c. */ | |
4726 | return fold (build (code, type, arg, | |
4727 | build_real (TREE_TYPE (arg), c2))); | |
4728 | } | |
4729 | else if (code == LT_EXPR || code == LE_EXPR) | |
4730 | { | |
4731 | REAL_VALUE_TYPE c2; | |
4732 | ||
4733 | REAL_ARITHMETIC (c2, MULT_EXPR, c, c); | |
4734 | real_convert (&c2, mode, &c2); | |
4735 | ||
4736 | if (REAL_VALUE_ISINF (c2)) | |
4737 | { | |
4738 | /* sqrt(x) < y is always true, when y is a very large | |
4739 | value and we don't care about NaNs or Infinities. */ | |
4740 | if (! HONOR_NANS (mode) && ! HONOR_INFINITIES (mode)) | |
4741 | return omit_one_operand (type, | |
4742 | convert (type, integer_one_node), | |
4743 | arg); | |
4744 | ||
4745 | /* sqrt(x) < y is x != +Inf when y is very large and we | |
4746 | don't care about NaNs. */ | |
4747 | if (! HONOR_NANS (mode)) | |
4748 | return fold (build (NE_EXPR, type, arg, | |
4749 | build_real (TREE_TYPE (arg), c2))); | |
4750 | ||
4751 | /* sqrt(x) < y is x >= 0 when y is very large and we | |
4752 | don't care about Infinities. */ | |
4753 | if (! HONOR_INFINITIES (mode)) | |
4754 | return fold (build (GE_EXPR, type, arg, | |
4755 | build_real (TREE_TYPE (arg), dconst0))); | |
4756 | ||
4757 | /* sqrt(x) < y is x >= 0 && x != +Inf, when y is large. */ | |
4758 | if ((*lang_hooks.decls.global_bindings_p) () != 0 | |
7a6cdb44 | 4759 | || CONTAINS_PLACEHOLDER_P (arg)) |
c876997f RS |
4760 | return NULL_TREE; |
4761 | ||
4762 | arg = save_expr (arg); | |
4763 | return fold (build (TRUTH_ANDIF_EXPR, type, | |
4764 | fold (build (GE_EXPR, type, arg, | |
4765 | build_real (TREE_TYPE (arg), | |
4766 | dconst0))), | |
4767 | fold (build (NE_EXPR, type, arg, | |
4768 | build_real (TREE_TYPE (arg), | |
4769 | c2))))); | |
4770 | } | |
4771 | ||
4772 | /* sqrt(x) < c is the same as x < c*c, if we ignore NaNs. */ | |
4773 | if (! HONOR_NANS (mode)) | |
4774 | return fold (build (code, type, arg, | |
4775 | build_real (TREE_TYPE (arg), c2))); | |
4776 | ||
4777 | /* sqrt(x) < c is the same as x >= 0 && x < c*c. */ | |
4778 | if ((*lang_hooks.decls.global_bindings_p) () == 0 | |
7a6cdb44 | 4779 | && ! CONTAINS_PLACEHOLDER_P (arg)) |
c876997f RS |
4780 | { |
4781 | arg = save_expr (arg); | |
4782 | return fold (build (TRUTH_ANDIF_EXPR, type, | |
4783 | fold (build (GE_EXPR, type, arg, | |
4784 | build_real (TREE_TYPE (arg), | |
4785 | dconst0))), | |
4786 | fold (build (code, type, arg, | |
4787 | build_real (TREE_TYPE (arg), | |
4788 | c2))))); | |
4789 | } | |
4790 | } | |
4791 | } | |
4792 | ||
4793 | return NULL_TREE; | |
4794 | } | |
4795 | ||
9ddae796 RS |
4796 | /* Subroutine of fold() that optimizes comparisons against Infinities, |
4797 | either +Inf or -Inf. | |
4798 | ||
4799 | CODE is the comparison operator: EQ_EXPR, NE_EXPR, GT_EXPR, LT_EXPR, | |
4800 | GE_EXPR or LE_EXPR. TYPE is the type of the result and ARG0 and ARG1 | |
4801 | are the operands of the comparison. ARG1 must be a TREE_REAL_CST. | |
4802 | ||
4803 | The function returns the constant folded tree if a simplification | |
4804 | can be made, and NULL_TREE otherwise. */ | |
4805 | ||
4806 | static tree | |
fa8db1f7 | 4807 | fold_inf_compare (enum tree_code code, tree type, tree arg0, tree arg1) |
9ddae796 | 4808 | { |
18c2511c RS |
4809 | enum machine_mode mode; |
4810 | REAL_VALUE_TYPE max; | |
4811 | tree temp; | |
4812 | bool neg; | |
4813 | ||
4814 | mode = TYPE_MODE (TREE_TYPE (arg0)); | |
4815 | ||
9ddae796 | 4816 | /* For negative infinity swap the sense of the comparison. */ |
18c2511c RS |
4817 | neg = REAL_VALUE_NEGATIVE (TREE_REAL_CST (arg1)); |
4818 | if (neg) | |
9ddae796 RS |
4819 | code = swap_tree_comparison (code); |
4820 | ||
4821 | switch (code) | |
4822 | { | |
4823 | case GT_EXPR: | |
4824 | /* x > +Inf is always false, if with ignore sNANs. */ | |
18c2511c | 4825 | if (HONOR_SNANS (mode)) |
9ddae796 RS |
4826 | return NULL_TREE; |
4827 | return omit_one_operand (type, | |
4828 | convert (type, integer_zero_node), | |
4829 | arg0); | |
4830 | ||
4831 | case LE_EXPR: | |
4832 | /* x <= +Inf is always true, if we don't case about NaNs. */ | |
18c2511c | 4833 | if (! HONOR_NANS (mode)) |
9ddae796 RS |
4834 | return omit_one_operand (type, |
4835 | convert (type, integer_one_node), | |
4836 | arg0); | |
4837 | ||
4838 | /* x <= +Inf is the same as x == x, i.e. isfinite(x). */ | |
4839 | if ((*lang_hooks.decls.global_bindings_p) () == 0 | |
7a6cdb44 | 4840 | && ! CONTAINS_PLACEHOLDER_P (arg0)) |
9ddae796 RS |
4841 | { |
4842 | arg0 = save_expr (arg0); | |
4843 | return fold (build (EQ_EXPR, type, arg0, arg0)); | |
4844 | } | |
4845 | break; | |
4846 | ||
18c2511c RS |
4847 | case EQ_EXPR: |
4848 | case GE_EXPR: | |
4849 | /* x == +Inf and x >= +Inf are always equal to x > DBL_MAX. */ | |
4850 | real_maxval (&max, neg, mode); | |
4851 | return fold (build (neg ? LT_EXPR : GT_EXPR, type, | |
4852 | arg0, build_real (TREE_TYPE (arg0), max))); | |
4853 | ||
4854 | case LT_EXPR: | |
4855 | /* x < +Inf is always equal to x <= DBL_MAX. */ | |
4856 | real_maxval (&max, neg, mode); | |
4857 | return fold (build (neg ? GE_EXPR : LE_EXPR, type, | |
4858 | arg0, build_real (TREE_TYPE (arg0), max))); | |
4859 | ||
4860 | case NE_EXPR: | |
4861 | /* x != +Inf is always equal to !(x > DBL_MAX). */ | |
4862 | real_maxval (&max, neg, mode); | |
4863 | if (! HONOR_NANS (mode)) | |
4864 | return fold (build (neg ? GE_EXPR : LE_EXPR, type, | |
4865 | arg0, build_real (TREE_TYPE (arg0), max))); | |
4866 | temp = fold (build (neg ? LT_EXPR : GT_EXPR, type, | |
4867 | arg0, build_real (TREE_TYPE (arg0), max))); | |
4868 | return fold (build1 (TRUTH_NOT_EXPR, type, temp)); | |
9ddae796 RS |
4869 | |
4870 | default: | |
4871 | break; | |
4872 | } | |
4873 | ||
4874 | return NULL_TREE; | |
4875 | } | |
71925bc0 | 4876 | |
7960bf22 JL |
4877 | /* If CODE with arguments ARG0 and ARG1 represents a single bit |
4878 | equality/inequality test, then return a simplified form of | |
4879 | the test using shifts and logical operations. Otherwise return | |
4880 | NULL. TYPE is the desired result type. */ | |
4881 | ||
4882 | tree | |
5671bf27 AJ |
4883 | fold_single_bit_test (enum tree_code code, tree arg0, tree arg1, |
4884 | tree result_type) | |
7960bf22 JL |
4885 | { |
4886 | /* If this is a TRUTH_NOT_EXPR, it may have a single bit test inside | |
4887 | operand 0. */ | |
4888 | if (code == TRUTH_NOT_EXPR) | |
4889 | { | |
4890 | code = TREE_CODE (arg0); | |
4891 | if (code != NE_EXPR && code != EQ_EXPR) | |
4892 | return NULL_TREE; | |
4893 | ||
4894 | /* Extract the arguments of the EQ/NE. */ | |
4895 | arg1 = TREE_OPERAND (arg0, 1); | |
4896 | arg0 = TREE_OPERAND (arg0, 0); | |
4897 | ||
4898 | /* This requires us to invert the code. */ | |
4899 | code = (code == EQ_EXPR ? NE_EXPR : EQ_EXPR); | |
4900 | } | |
4901 | ||
4902 | /* If this is testing a single bit, we can optimize the test. */ | |
4903 | if ((code == NE_EXPR || code == EQ_EXPR) | |
4904 | && TREE_CODE (arg0) == BIT_AND_EXPR && integer_zerop (arg1) | |
4905 | && integer_pow2p (TREE_OPERAND (arg0, 1))) | |
4906 | { | |
4907 | tree inner = TREE_OPERAND (arg0, 0); | |
4908 | tree type = TREE_TYPE (arg0); | |
4909 | int bitnum = tree_log2 (TREE_OPERAND (arg0, 1)); | |
4910 | enum machine_mode operand_mode = TYPE_MODE (type); | |
4911 | int ops_unsigned; | |
4912 | tree signed_type, unsigned_type; | |
4913 | tree arg00; | |
4914 | ||
4915 | /* If we have (A & C) != 0 where C is the sign bit of A, convert | |
4916 | this into A < 0. Similarly for (A & C) == 0 into A >= 0. */ | |
4917 | arg00 = sign_bit_p (TREE_OPERAND (arg0, 0), TREE_OPERAND (arg0, 1)); | |
4918 | if (arg00 != NULL_TREE) | |
4919 | { | |
4920 | tree stype = (*lang_hooks.types.signed_type) (TREE_TYPE (arg00)); | |
60cd4dae | 4921 | return fold (build (code == EQ_EXPR ? GE_EXPR : LT_EXPR, result_type, |
7960bf22 JL |
4922 | convert (stype, arg00), |
4923 | convert (stype, integer_zero_node))); | |
4924 | } | |
c87d821b KH |
4925 | |
4926 | /* At this point, we know that arg0 is not testing the sign bit. */ | |
4927 | if (TYPE_PRECISION (type) - 1 == bitnum) | |
4928 | abort (); | |
7960bf22 JL |
4929 | |
4930 | /* Otherwise we have (A & C) != 0 where C is a single bit, | |
4931 | convert that into ((A >> C2) & 1). Where C2 = log2(C). | |
4932 | Similarly for (A & C) == 0. */ | |
4933 | ||
4934 | /* If INNER is a right shift of a constant and it plus BITNUM does | |
4935 | not overflow, adjust BITNUM and INNER. */ | |
4936 | if (TREE_CODE (inner) == RSHIFT_EXPR | |
4937 | && TREE_CODE (TREE_OPERAND (inner, 1)) == INTEGER_CST | |
4938 | && TREE_INT_CST_HIGH (TREE_OPERAND (inner, 1)) == 0 | |
4939 | && bitnum < TYPE_PRECISION (type) | |
4940 | && 0 > compare_tree_int (TREE_OPERAND (inner, 1), | |
4941 | bitnum - TYPE_PRECISION (type))) | |
4942 | { | |
4943 | bitnum += TREE_INT_CST_LOW (TREE_OPERAND (inner, 1)); | |
4944 | inner = TREE_OPERAND (inner, 0); | |
4945 | } | |
4946 | ||
4947 | /* If we are going to be able to omit the AND below, we must do our | |
4948 | operations as unsigned. If we must use the AND, we have a choice. | |
4949 | Normally unsigned is faster, but for some machines signed is. */ | |
7960bf22 | 4950 | #ifdef LOAD_EXTEND_OP |
c87d821b | 4951 | ops_unsigned = (LOAD_EXTEND_OP (operand_mode) == SIGN_EXTEND ? 0 : 1); |
7960bf22 | 4952 | #else |
c87d821b | 4953 | ops_unsigned = 1; |
7960bf22 | 4954 | #endif |
7960bf22 JL |
4955 | |
4956 | signed_type = (*lang_hooks.types.type_for_mode) (operand_mode, 0); | |
4957 | unsigned_type = (*lang_hooks.types.type_for_mode) (operand_mode, 1); | |
4958 | ||
4959 | if (bitnum != 0) | |
4960 | inner = build (RSHIFT_EXPR, ops_unsigned ? unsigned_type : signed_type, | |
4961 | inner, size_int (bitnum)); | |
4962 | ||
4963 | if (code == EQ_EXPR) | |
4964 | inner = build (BIT_XOR_EXPR, ops_unsigned ? unsigned_type : signed_type, | |
4965 | inner, integer_one_node); | |
4966 | ||
4967 | /* Put the AND last so it can combine with more things. */ | |
c87d821b KH |
4968 | inner = build (BIT_AND_EXPR, ops_unsigned ? unsigned_type : signed_type, |
4969 | inner, integer_one_node); | |
7960bf22 JL |
4970 | |
4971 | /* Make sure to return the proper type. */ | |
4972 | if (TREE_TYPE (inner) != result_type) | |
4973 | inner = convert (result_type, inner); | |
4974 | ||
4975 | return inner; | |
4976 | } | |
4977 | return NULL_TREE; | |
4978 | } | |
5dfa45d0 | 4979 | |
37af03cb RS |
4980 | /* Test whether it is preferable two swap two operands, ARG0 and |
4981 | ARG1, for example because ARG0 is an integer constant and ARG1 | |
4982 | isn't. */ | |
4983 | ||
4984 | static bool | |
4985 | tree_swap_operands_p (tree arg0, tree arg1) | |
4986 | { | |
4987 | STRIP_SIGN_NOPS (arg0); | |
4988 | STRIP_SIGN_NOPS (arg1); | |
4989 | ||
4990 | if (TREE_CODE (arg1) == INTEGER_CST) | |
4991 | return 0; | |
4992 | if (TREE_CODE (arg0) == INTEGER_CST) | |
4993 | return 1; | |
4994 | ||
4995 | if (TREE_CODE (arg1) == REAL_CST) | |
4996 | return 0; | |
4997 | if (TREE_CODE (arg0) == REAL_CST) | |
4998 | return 1; | |
4999 | ||
5000 | if (TREE_CODE (arg1) == COMPLEX_CST) | |
5001 | return 0; | |
5002 | if (TREE_CODE (arg0) == COMPLEX_CST) | |
5003 | return 1; | |
5004 | ||
5005 | if (TREE_CONSTANT (arg1)) | |
5006 | return 0; | |
5007 | if (TREE_CONSTANT (arg0)) | |
5008 | return 1; | |
5009 | ||
37af03cb RS |
5010 | return 0; |
5011 | } | |
5012 | ||
6d716ca8 RS |
5013 | /* Perform constant folding and related simplification of EXPR. |
5014 | The related simplifications include x*1 => x, x*0 => 0, etc., | |
5015 | and application of the associative law. | |
5016 | NOP_EXPR conversions may be removed freely (as long as we | |
5017 | are careful not to change the C type of the overall expression) | |
5018 | We cannot simplify through a CONVERT_EXPR, FIX_EXPR or FLOAT_EXPR, | |
5019 | but we can constant-fold them if they have constant operands. */ | |
5020 | ||
5dfa45d0 JJ |
5021 | #ifdef ENABLE_FOLD_CHECKING |
5022 | # define fold(x) fold_1 (x) | |
5023 | static tree fold_1 (tree); | |
5024 | static | |
5025 | #endif | |
6d716ca8 | 5026 | tree |
fa8db1f7 | 5027 | fold (tree expr) |
6d716ca8 | 5028 | { |
5dfa45d0 | 5029 | tree t = expr, orig_t; |
6d716ca8 | 5030 | tree t1 = NULL_TREE; |
c05a9b68 | 5031 | tree tem; |
6d716ca8 | 5032 | tree type = TREE_TYPE (expr); |
b3694847 SS |
5033 | tree arg0 = NULL_TREE, arg1 = NULL_TREE; |
5034 | enum tree_code code = TREE_CODE (t); | |
5035 | int kind = TREE_CODE_CLASS (code); | |
c05a9b68 | 5036 | int invert; |
6d716ca8 RS |
5037 | /* WINS will be nonzero when the switch is done |
5038 | if all operands are constant. */ | |
6d716ca8 RS |
5039 | int wins = 1; |
5040 | ||
b6cc0a72 | 5041 | /* Don't try to process an RTL_EXPR since its operands aren't trees. |
5fd7f37d | 5042 | Likewise for a SAVE_EXPR that's already been evaluated. */ |
dea8be3e | 5043 | if (code == RTL_EXPR || (code == SAVE_EXPR && SAVE_EXPR_RTL (t) != 0)) |
ac27d589 RK |
5044 | return t; |
5045 | ||
1796dff4 RH |
5046 | /* Return right away if a constant. */ |
5047 | if (kind == 'c') | |
5048 | return t; | |
b6cc0a72 | 5049 | |
dbecbbe4 JL |
5050 | #ifdef MAX_INTEGER_COMPUTATION_MODE |
5051 | check_max_integer_computation_mode (expr); | |
5052 | #endif | |
5dfa45d0 | 5053 | orig_t = t; |
dbecbbe4 | 5054 | |
1b81aa14 RS |
5055 | if (code == NOP_EXPR || code == FLOAT_EXPR || code == CONVERT_EXPR) |
5056 | { | |
1cc1b11a RS |
5057 | tree subop; |
5058 | ||
1b81aa14 RS |
5059 | /* Special case for conversion ops that can have fixed point args. */ |
5060 | arg0 = TREE_OPERAND (t, 0); | |
5061 | ||
5062 | /* Don't use STRIP_NOPS, because signedness of argument type matters. */ | |
5063 | if (arg0 != 0) | |
14a774a9 | 5064 | STRIP_SIGN_NOPS (arg0); |
1b81aa14 | 5065 | |
1cc1b11a RS |
5066 | if (arg0 != 0 && TREE_CODE (arg0) == COMPLEX_CST) |
5067 | subop = TREE_REALPART (arg0); | |
5068 | else | |
5069 | subop = arg0; | |
5070 | ||
5071 | if (subop != 0 && TREE_CODE (subop) != INTEGER_CST | |
37af03cb | 5072 | && TREE_CODE (subop) != REAL_CST) |
1b81aa14 RS |
5073 | /* Note that TREE_CONSTANT isn't enough: |
5074 | static var addresses are constant but we can't | |
5075 | do arithmetic on them. */ | |
5076 | wins = 0; | |
5077 | } | |
68ad9159 | 5078 | else if (IS_EXPR_CODE_CLASS (kind)) |
6d716ca8 | 5079 | { |
b3694847 SS |
5080 | int len = first_rtl_op (code); |
5081 | int i; | |
6d716ca8 RS |
5082 | for (i = 0; i < len; i++) |
5083 | { | |
5084 | tree op = TREE_OPERAND (t, i); | |
1cc1b11a | 5085 | tree subop; |
6d716ca8 RS |
5086 | |
5087 | if (op == 0) | |
5088 | continue; /* Valid for CALL_EXPR, at least. */ | |
5089 | ||
b8a91430 RK |
5090 | if (kind == '<' || code == RSHIFT_EXPR) |
5091 | { | |
5092 | /* Signedness matters here. Perhaps we can refine this | |
5093 | later. */ | |
14a774a9 | 5094 | STRIP_SIGN_NOPS (op); |
b8a91430 RK |
5095 | } |
5096 | else | |
13eb1f7f RK |
5097 | /* Strip any conversions that don't change the mode. */ |
5098 | STRIP_NOPS (op); | |
b6cc0a72 | 5099 | |
1cc1b11a RS |
5100 | if (TREE_CODE (op) == COMPLEX_CST) |
5101 | subop = TREE_REALPART (op); | |
5102 | else | |
5103 | subop = op; | |
5104 | ||
5105 | if (TREE_CODE (subop) != INTEGER_CST | |
ba31d94e | 5106 | && TREE_CODE (subop) != REAL_CST) |
6d716ca8 RS |
5107 | /* Note that TREE_CONSTANT isn't enough: |
5108 | static var addresses are constant but we can't | |
5109 | do arithmetic on them. */ | |
5110 | wins = 0; | |
5111 | ||
5112 | if (i == 0) | |
5113 | arg0 = op; | |
5114 | else if (i == 1) | |
5115 | arg1 = op; | |
5116 | } | |
5117 | } | |
5118 | ||
5119 | /* If this is a commutative operation, and ARG0 is a constant, move it | |
5120 | to ARG1 to reduce the number of tests below. */ | |
5121 | if ((code == PLUS_EXPR || code == MULT_EXPR || code == MIN_EXPR | |
5122 | || code == MAX_EXPR || code == BIT_IOR_EXPR || code == BIT_XOR_EXPR | |
5123 | || code == BIT_AND_EXPR) | |
37af03cb RS |
5124 | && tree_swap_operands_p (arg0, arg1)) |
5125 | return fold (build (code, type, arg1, arg0)); | |
6d716ca8 RS |
5126 | |
5127 | /* Now WINS is set as described above, | |
5128 | ARG0 is the first operand of EXPR, | |
5129 | and ARG1 is the second operand (if it has more than one operand). | |
5130 | ||
5131 | First check for cases where an arithmetic operation is applied to a | |
5132 | compound, conditional, or comparison operation. Push the arithmetic | |
5133 | operation inside the compound or conditional to see if any folding | |
5134 | can then be done. Convert comparison to conditional for this purpose. | |
5135 | The also optimizes non-constant cases that used to be done in | |
96d4cf0a RK |
5136 | expand_expr. |
5137 | ||
fba5638f | 5138 | Before we do that, see if this is a BIT_AND_EXPR or a BIT_IOR_EXPR, |
61f275ff RK |
5139 | one of the operands is a comparison and the other is a comparison, a |
5140 | BIT_AND_EXPR with the constant 1, or a truth value. In that case, the | |
5141 | code below would make the expression more complex. Change it to a | |
b6cc0a72 | 5142 | TRUTH_{AND,OR}_EXPR. Likewise, convert a similar NE_EXPR to |
2df46b06 | 5143 | TRUTH_XOR_EXPR and an EQ_EXPR to the inversion of a TRUTH_XOR_EXPR. */ |
96d4cf0a | 5144 | |
2df46b06 RK |
5145 | if ((code == BIT_AND_EXPR || code == BIT_IOR_EXPR |
5146 | || code == EQ_EXPR || code == NE_EXPR) | |
61f275ff RK |
5147 | && ((truth_value_p (TREE_CODE (arg0)) |
5148 | && (truth_value_p (TREE_CODE (arg1)) | |
96d4cf0a RK |
5149 | || (TREE_CODE (arg1) == BIT_AND_EXPR |
5150 | && integer_onep (TREE_OPERAND (arg1, 1))))) | |
61f275ff RK |
5151 | || (truth_value_p (TREE_CODE (arg1)) |
5152 | && (truth_value_p (TREE_CODE (arg0)) | |
96d4cf0a RK |
5153 | || (TREE_CODE (arg0) == BIT_AND_EXPR |
5154 | && integer_onep (TREE_OPERAND (arg0, 1))))))) | |
2df46b06 RK |
5155 | { |
5156 | t = fold (build (code == BIT_AND_EXPR ? TRUTH_AND_EXPR | |
5157 | : code == BIT_IOR_EXPR ? TRUTH_OR_EXPR | |
5158 | : TRUTH_XOR_EXPR, | |
5159 | type, arg0, arg1)); | |
5160 | ||
5161 | if (code == EQ_EXPR) | |
5162 | t = invert_truthvalue (t); | |
5163 | ||
5164 | return t; | |
5165 | } | |
96d4cf0a | 5166 | |
6d716ca8 RS |
5167 | if (TREE_CODE_CLASS (code) == '1') |
5168 | { | |
5169 | if (TREE_CODE (arg0) == COMPOUND_EXPR) | |
5170 | return build (COMPOUND_EXPR, type, TREE_OPERAND (arg0, 0), | |
5171 | fold (build1 (code, type, TREE_OPERAND (arg0, 1)))); | |
5172 | else if (TREE_CODE (arg0) == COND_EXPR) | |
b8eb43a2 | 5173 | { |
9402f6fb RS |
5174 | tree arg01 = TREE_OPERAND (arg0, 1); |
5175 | tree arg02 = TREE_OPERAND (arg0, 2); | |
5176 | if (! VOID_TYPE_P (TREE_TYPE (arg01))) | |
5177 | arg01 = fold (build1 (code, type, arg01)); | |
5178 | if (! VOID_TYPE_P (TREE_TYPE (arg02))) | |
5179 | arg02 = fold (build1 (code, type, arg02)); | |
b8eb43a2 | 5180 | t = fold (build (COND_EXPR, type, TREE_OPERAND (arg0, 0), |
9402f6fb | 5181 | arg01, arg02)); |
b8eb43a2 RK |
5182 | |
5183 | /* If this was a conversion, and all we did was to move into | |
e1f56f62 RK |
5184 | inside the COND_EXPR, bring it back out. But leave it if |
5185 | it is a conversion from integer to integer and the | |
5186 | result precision is no wider than a word since such a | |
5187 | conversion is cheap and may be optimized away by combine, | |
5188 | while it couldn't if it were outside the COND_EXPR. Then return | |
5189 | so we don't get into an infinite recursion loop taking the | |
5190 | conversion out and then back in. */ | |
b8eb43a2 RK |
5191 | |
5192 | if ((code == NOP_EXPR || code == CONVERT_EXPR | |
5193 | || code == NON_LVALUE_EXPR) | |
5194 | && TREE_CODE (t) == COND_EXPR | |
5195 | && TREE_CODE (TREE_OPERAND (t, 1)) == code | |
459a2653 | 5196 | && TREE_CODE (TREE_OPERAND (t, 2)) == code |
9402f6fb RS |
5197 | && ! VOID_TYPE_P (TREE_OPERAND (t, 1)) |
5198 | && ! VOID_TYPE_P (TREE_OPERAND (t, 2)) | |
459a2653 | 5199 | && (TREE_TYPE (TREE_OPERAND (TREE_OPERAND (t, 1), 0)) |
e1f56f62 RK |
5200 | == TREE_TYPE (TREE_OPERAND (TREE_OPERAND (t, 2), 0))) |
5201 | && ! (INTEGRAL_TYPE_P (TREE_TYPE (t)) | |
d4b60170 RK |
5202 | && (INTEGRAL_TYPE_P |
5203 | (TREE_TYPE (TREE_OPERAND (TREE_OPERAND (t, 1), 0)))) | |
e1f56f62 | 5204 | && TYPE_PRECISION (TREE_TYPE (t)) <= BITS_PER_WORD)) |
b8eb43a2 RK |
5205 | t = build1 (code, type, |
5206 | build (COND_EXPR, | |
d4b60170 RK |
5207 | TREE_TYPE (TREE_OPERAND |
5208 | (TREE_OPERAND (t, 1), 0)), | |
b8eb43a2 RK |
5209 | TREE_OPERAND (t, 0), |
5210 | TREE_OPERAND (TREE_OPERAND (t, 1), 0), | |
5211 | TREE_OPERAND (TREE_OPERAND (t, 2), 0))); | |
5212 | return t; | |
5213 | } | |
b6cc0a72 | 5214 | else if (TREE_CODE_CLASS (TREE_CODE (arg0)) == '<') |
6d716ca8 RS |
5215 | return fold (build (COND_EXPR, type, arg0, |
5216 | fold (build1 (code, type, integer_one_node)), | |
5217 | fold (build1 (code, type, integer_zero_node)))); | |
5218 | } | |
cbcafd35 OH |
5219 | else if (TREE_CODE_CLASS (code) == '<' |
5220 | && TREE_CODE (arg0) == COMPOUND_EXPR) | |
5221 | return build (COMPOUND_EXPR, type, TREE_OPERAND (arg0, 0), | |
5222 | fold (build (code, type, TREE_OPERAND (arg0, 1), arg1))); | |
5223 | else if (TREE_CODE_CLASS (code) == '<' | |
5224 | && TREE_CODE (arg1) == COMPOUND_EXPR) | |
5225 | return build (COMPOUND_EXPR, type, TREE_OPERAND (arg1, 0), | |
5226 | fold (build (code, type, arg0, TREE_OPERAND (arg1, 1)))); | |
96d4cf0a RK |
5227 | else if (TREE_CODE_CLASS (code) == '2' |
5228 | || TREE_CODE_CLASS (code) == '<') | |
6d716ca8 | 5229 | { |
5c7cd663 AH |
5230 | if (TREE_CODE (arg1) == COMPOUND_EXPR |
5231 | && ! TREE_SIDE_EFFECTS (TREE_OPERAND (arg1, 0)) | |
5232 | && ! TREE_SIDE_EFFECTS (arg0)) | |
6d716ca8 | 5233 | return build (COMPOUND_EXPR, type, TREE_OPERAND (arg1, 0), |
96d4cf0a RK |
5234 | fold (build (code, type, |
5235 | arg0, TREE_OPERAND (arg1, 1)))); | |
f0eebf28 RK |
5236 | else if ((TREE_CODE (arg1) == COND_EXPR |
5237 | || (TREE_CODE_CLASS (TREE_CODE (arg1)) == '<' | |
5238 | && TREE_CODE_CLASS (code) != '<')) | |
ab87f8c8 JL |
5239 | && (TREE_CODE (arg0) != COND_EXPR |
5240 | || count_cond (arg0, 25) + count_cond (arg1, 25) <= 25) | |
9ec36da5 | 5241 | && (! TREE_SIDE_EFFECTS (arg0) |
43577e6b | 5242 | || ((*lang_hooks.decls.global_bindings_p) () == 0 |
7a6cdb44 | 5243 | && ! CONTAINS_PLACEHOLDER_P (arg0)))) |
dd3f0101 | 5244 | return |
68626d4f MM |
5245 | fold_binary_op_with_conditional_arg (code, type, arg1, arg0, |
5246 | /*cond_first_p=*/0); | |
6d716ca8 RS |
5247 | else if (TREE_CODE (arg0) == COMPOUND_EXPR) |
5248 | return build (COMPOUND_EXPR, type, TREE_OPERAND (arg0, 0), | |
5249 | fold (build (code, type, TREE_OPERAND (arg0, 1), arg1))); | |
f0eebf28 RK |
5250 | else if ((TREE_CODE (arg0) == COND_EXPR |
5251 | || (TREE_CODE_CLASS (TREE_CODE (arg0)) == '<' | |
5252 | && TREE_CODE_CLASS (code) != '<')) | |
ab87f8c8 JL |
5253 | && (TREE_CODE (arg1) != COND_EXPR |
5254 | || count_cond (arg0, 25) + count_cond (arg1, 25) <= 25) | |
9ec36da5 | 5255 | && (! TREE_SIDE_EFFECTS (arg1) |
43577e6b | 5256 | || ((*lang_hooks.decls.global_bindings_p) () == 0 |
7a6cdb44 | 5257 | && ! CONTAINS_PLACEHOLDER_P (arg1)))) |
dd3f0101 | 5258 | return |
68626d4f MM |
5259 | fold_binary_op_with_conditional_arg (code, type, arg0, arg1, |
5260 | /*cond_first_p=*/1); | |
6d716ca8 | 5261 | } |
b6cc0a72 | 5262 | |
6d716ca8 RS |
5263 | switch (code) |
5264 | { | |
5265 | case INTEGER_CST: | |
5266 | case REAL_CST: | |
69ef87e2 | 5267 | case VECTOR_CST: |
6d716ca8 RS |
5268 | case STRING_CST: |
5269 | case COMPLEX_CST: | |
5270 | case CONSTRUCTOR: | |
5271 | return t; | |
5272 | ||
5273 | case CONST_DECL: | |
5274 | return fold (DECL_INITIAL (t)); | |
5275 | ||
5276 | case NOP_EXPR: | |
5277 | case FLOAT_EXPR: | |
5278 | case CONVERT_EXPR: | |
5279 | case FIX_TRUNC_EXPR: | |
5280 | /* Other kinds of FIX are not handled properly by fold_convert. */ | |
33558beb | 5281 | |
e1f56f62 RK |
5282 | if (TREE_TYPE (TREE_OPERAND (t, 0)) == TREE_TYPE (t)) |
5283 | return TREE_OPERAND (t, 0); | |
5284 | ||
7e139075 RK |
5285 | /* Handle cases of two conversions in a row. */ |
5286 | if (TREE_CODE (TREE_OPERAND (t, 0)) == NOP_EXPR | |
5287 | || TREE_CODE (TREE_OPERAND (t, 0)) == CONVERT_EXPR) | |
5288 | { | |
5289 | tree inside_type = TREE_TYPE (TREE_OPERAND (TREE_OPERAND (t, 0), 0)); | |
5290 | tree inter_type = TREE_TYPE (TREE_OPERAND (t, 0)); | |
5291 | tree final_type = TREE_TYPE (t); | |
5292 | int inside_int = INTEGRAL_TYPE_P (inside_type); | |
7f0b305c | 5293 | int inside_ptr = POINTER_TYPE_P (inside_type); |
7e139075 | 5294 | int inside_float = FLOAT_TYPE_P (inside_type); |
770ae6cc | 5295 | unsigned int inside_prec = TYPE_PRECISION (inside_type); |
7e139075 RK |
5296 | int inside_unsignedp = TREE_UNSIGNED (inside_type); |
5297 | int inter_int = INTEGRAL_TYPE_P (inter_type); | |
7f0b305c | 5298 | int inter_ptr = POINTER_TYPE_P (inter_type); |
7e139075 | 5299 | int inter_float = FLOAT_TYPE_P (inter_type); |
770ae6cc | 5300 | unsigned int inter_prec = TYPE_PRECISION (inter_type); |
7e139075 RK |
5301 | int inter_unsignedp = TREE_UNSIGNED (inter_type); |
5302 | int final_int = INTEGRAL_TYPE_P (final_type); | |
7f0b305c | 5303 | int final_ptr = POINTER_TYPE_P (final_type); |
7e139075 | 5304 | int final_float = FLOAT_TYPE_P (final_type); |
770ae6cc | 5305 | unsigned int final_prec = TYPE_PRECISION (final_type); |
7e139075 RK |
5306 | int final_unsignedp = TREE_UNSIGNED (final_type); |
5307 | ||
b6cc0a72 | 5308 | /* In addition to the cases of two conversions in a row |
7e139075 RK |
5309 | handled below, if we are converting something to its own |
5310 | type via an object of identical or wider precision, neither | |
5311 | conversion is needed. */ | |
30355eaa | 5312 | if (TYPE_MAIN_VARIANT (inside_type) == TYPE_MAIN_VARIANT (final_type) |
7e139075 RK |
5313 | && ((inter_int && final_int) || (inter_float && final_float)) |
5314 | && inter_prec >= final_prec) | |
72bd1f9e | 5315 | return convert (final_type, TREE_OPERAND (TREE_OPERAND (t, 0), 0)); |
7e139075 RK |
5316 | |
5317 | /* Likewise, if the intermediate and final types are either both | |
5318 | float or both integer, we don't need the middle conversion if | |
5319 | it is wider than the final type and doesn't change the signedness | |
7f0b305c | 5320 | (for integers). Avoid this if the final type is a pointer |
410d3f5d RK |
5321 | since then we sometimes need the inner conversion. Likewise if |
5322 | the outer has a precision not equal to the size of its mode. */ | |
7e139075 RK |
5323 | if ((((inter_int || inter_ptr) && (inside_int || inside_ptr)) |
5324 | || (inter_float && inside_float)) | |
5325 | && inter_prec >= inside_prec | |
7f0b305c | 5326 | && (inter_float || inter_unsignedp == inside_unsignedp) |
410d3f5d RK |
5327 | && ! (final_prec != GET_MODE_BITSIZE (TYPE_MODE (final_type)) |
5328 | && TYPE_MODE (final_type) == TYPE_MODE (inter_type)) | |
7f0b305c | 5329 | && ! final_ptr) |
7e139075 RK |
5330 | return convert (final_type, TREE_OPERAND (TREE_OPERAND (t, 0), 0)); |
5331 | ||
ba3ad5e0 PDM |
5332 | /* If we have a sign-extension of a zero-extended value, we can |
5333 | replace that by a single zero-extension. */ | |
5334 | if (inside_int && inter_int && final_int | |
5335 | && inside_prec < inter_prec && inter_prec < final_prec | |
5336 | && inside_unsignedp && !inter_unsignedp) | |
5337 | return convert (final_type, TREE_OPERAND (TREE_OPERAND (t, 0), 0)); | |
5338 | ||
7e139075 RK |
5339 | /* Two conversions in a row are not needed unless: |
5340 | - some conversion is floating-point (overstrict for now), or | |
5341 | - the intermediate type is narrower than both initial and | |
5342 | final, or | |
5343 | - the intermediate type and innermost type differ in signedness, | |
5344 | and the outermost type is wider than the intermediate, or | |
5345 | - the initial type is a pointer type and the precisions of the | |
5346 | intermediate and final types differ, or | |
b6cc0a72 | 5347 | - the final type is a pointer type and the precisions of the |
7e139075 RK |
5348 | initial and intermediate types differ. */ |
5349 | if (! inside_float && ! inter_float && ! final_float | |
5350 | && (inter_prec > inside_prec || inter_prec > final_prec) | |
5351 | && ! (inside_int && inter_int | |
5352 | && inter_unsignedp != inside_unsignedp | |
5353 | && inter_prec < final_prec) | |
5354 | && ((inter_unsignedp && inter_prec > inside_prec) | |
5355 | == (final_unsignedp && final_prec > inter_prec)) | |
5356 | && ! (inside_ptr && inter_prec != final_prec) | |
410d3f5d RK |
5357 | && ! (final_ptr && inside_prec != inter_prec) |
5358 | && ! (final_prec != GET_MODE_BITSIZE (TYPE_MODE (final_type)) | |
5359 | && TYPE_MODE (final_type) == TYPE_MODE (inter_type)) | |
5360 | && ! final_ptr) | |
7e139075 RK |
5361 | return convert (final_type, TREE_OPERAND (TREE_OPERAND (t, 0), 0)); |
5362 | } | |
6d716ca8 RS |
5363 | |
5364 | if (TREE_CODE (TREE_OPERAND (t, 0)) == MODIFY_EXPR | |
d8f6dbb9 RS |
5365 | && TREE_CONSTANT (TREE_OPERAND (TREE_OPERAND (t, 0), 1)) |
5366 | /* Detect assigning a bitfield. */ | |
5367 | && !(TREE_CODE (TREE_OPERAND (TREE_OPERAND (t, 0), 0)) == COMPONENT_REF | |
5368 | && DECL_BIT_FIELD (TREE_OPERAND (TREE_OPERAND (TREE_OPERAND (t, 0), 0), 1)))) | |
6d716ca8 | 5369 | { |
d8f6dbb9 | 5370 | /* Don't leave an assignment inside a conversion |
f72aed24 | 5371 | unless assigning a bitfield. */ |
6d716ca8 | 5372 | tree prev = TREE_OPERAND (t, 0); |
5dfa45d0 JJ |
5373 | if (t == orig_t) |
5374 | t = copy_node (t); | |
6d716ca8 RS |
5375 | TREE_OPERAND (t, 0) = TREE_OPERAND (prev, 1); |
5376 | /* First do the assignment, then return converted constant. */ | |
5377 | t = build (COMPOUND_EXPR, TREE_TYPE (t), prev, fold (t)); | |
5378 | TREE_USED (t) = 1; | |
5379 | return t; | |
5380 | } | |
58c2956c RS |
5381 | |
5382 | /* Convert (T)(x & c) into (T)x & (T)c, if c is an integer | |
5383 | constants (if x has signed type, the sign bit cannot be set | |
5384 | in c). This folds extension into the BIT_AND_EXPR. */ | |
5385 | if (INTEGRAL_TYPE_P (TREE_TYPE (t)) | |
57f851a3 | 5386 | && TREE_CODE (TREE_TYPE (t)) != BOOLEAN_TYPE |
58c2956c RS |
5387 | && TREE_CODE (TREE_OPERAND (t, 0)) == BIT_AND_EXPR |
5388 | && TREE_CODE (TREE_OPERAND (TREE_OPERAND (t, 0), 1)) == INTEGER_CST) | |
5389 | { | |
5390 | tree and = TREE_OPERAND (t, 0); | |
5391 | tree and0 = TREE_OPERAND (and, 0), and1 = TREE_OPERAND (and, 1); | |
5392 | int change = 0; | |
5393 | ||
5394 | if (TREE_UNSIGNED (TREE_TYPE (and)) | |
5395 | || (TYPE_PRECISION (TREE_TYPE (t)) | |
5396 | <= TYPE_PRECISION (TREE_TYPE (and)))) | |
5397 | change = 1; | |
5398 | else if (TYPE_PRECISION (TREE_TYPE (and1)) | |
5399 | <= HOST_BITS_PER_WIDE_INT | |
5400 | && host_integerp (and1, 1)) | |
5401 | { | |
5402 | unsigned HOST_WIDE_INT cst; | |
5403 | ||
5404 | cst = tree_low_cst (and1, 1); | |
5405 | cst &= (HOST_WIDE_INT) -1 | |
5406 | << (TYPE_PRECISION (TREE_TYPE (and1)) - 1); | |
5407 | change = (cst == 0); | |
5408 | #ifdef LOAD_EXTEND_OP | |
5409 | if (change | |
5410 | && (LOAD_EXTEND_OP (TYPE_MODE (TREE_TYPE (and0))) | |
5411 | == ZERO_EXTEND)) | |
5412 | { | |
a32db605 | 5413 | tree uns = (*lang_hooks.types.unsigned_type) (TREE_TYPE (and0)); |
58c2956c | 5414 | and0 = convert (uns, and0); |
fa8db1f7 | 5415 | and1 = convert (uns, and1); |
58c2956c RS |
5416 | } |
5417 | #endif | |
5418 | } | |
5419 | if (change) | |
5420 | return fold (build (BIT_AND_EXPR, TREE_TYPE (t), | |
5421 | convert (TREE_TYPE (t), and0), | |
5422 | convert (TREE_TYPE (t), and1))); | |
5423 | } | |
5424 | ||
6d716ca8 RS |
5425 | if (!wins) |
5426 | { | |
5dfa45d0 JJ |
5427 | if (TREE_CONSTANT (t) != TREE_CONSTANT (arg0)) |
5428 | { | |
5429 | if (t == orig_t) | |
5430 | t = copy_node (t); | |
5431 | TREE_CONSTANT (t) = TREE_CONSTANT (arg0); | |
5432 | } | |
6d716ca8 RS |
5433 | return t; |
5434 | } | |
5435 | return fold_convert (t, arg0); | |
5436 | ||
ed239f5a RK |
5437 | case VIEW_CONVERT_EXPR: |
5438 | if (TREE_CODE (TREE_OPERAND (t, 0)) == VIEW_CONVERT_EXPR) | |
5439 | return build1 (VIEW_CONVERT_EXPR, type, | |
5440 | TREE_OPERAND (TREE_OPERAND (t, 0), 0)); | |
5441 | return t; | |
5442 | ||
e082358b | 5443 | case COMPONENT_REF: |
7a6cdb44 RK |
5444 | if (TREE_CODE (arg0) == CONSTRUCTOR |
5445 | && ! type_contains_placeholder_p (TREE_TYPE (arg0))) | |
3ac4f0e6 JM |
5446 | { |
5447 | tree m = purpose_member (arg1, CONSTRUCTOR_ELTS (arg0)); | |
5448 | if (m) | |
5449 | t = TREE_VALUE (m); | |
5450 | } | |
e082358b JM |
5451 | return t; |
5452 | ||
6d716ca8 | 5453 | case RANGE_EXPR: |
5dfa45d0 JJ |
5454 | if (TREE_CONSTANT (t) != wins) |
5455 | { | |
5456 | if (t == orig_t) | |
5457 | t = copy_node (t); | |
5458 | TREE_CONSTANT (t) = wins; | |
5459 | } | |
6d716ca8 RS |
5460 | return t; |
5461 | ||
5462 | case NEGATE_EXPR: | |
5463 | if (wins) | |
5464 | { | |
5465 | if (TREE_CODE (arg0) == INTEGER_CST) | |
5466 | { | |
f9e158c3 JM |
5467 | unsigned HOST_WIDE_INT low; |
5468 | HOST_WIDE_INT high; | |
fe3e8e40 RS |
5469 | int overflow = neg_double (TREE_INT_CST_LOW (arg0), |
5470 | TREE_INT_CST_HIGH (arg0), | |
5471 | &low, &high); | |
5472 | t = build_int_2 (low, high); | |
6d716ca8 | 5473 | TREE_TYPE (t) = type; |
dc3907c5 PE |
5474 | TREE_OVERFLOW (t) |
5475 | = (TREE_OVERFLOW (arg0) | |
0c9cabe7 | 5476 | | force_fit_type (t, overflow && !TREE_UNSIGNED (type))); |
dc3907c5 PE |
5477 | TREE_CONSTANT_OVERFLOW (t) |
5478 | = TREE_OVERFLOW (t) | TREE_CONSTANT_OVERFLOW (arg0); | |
6d716ca8 RS |
5479 | } |
5480 | else if (TREE_CODE (arg0) == REAL_CST) | |
5481 | t = build_real (type, REAL_VALUE_NEGATE (TREE_REAL_CST (arg0))); | |
6d716ca8 RS |
5482 | } |
5483 | else if (TREE_CODE (arg0) == NEGATE_EXPR) | |
5484 | return TREE_OPERAND (arg0, 0); | |
b1a6f8db JH |
5485 | /* Convert -((double)float) into (double)(-float). */ |
5486 | else if (TREE_CODE (arg0) == NOP_EXPR | |
5487 | && TREE_CODE (type) == REAL_TYPE) | |
5488 | { | |
5489 | tree targ0 = strip_float_extensions (arg0); | |
5490 | if (targ0 != arg0) | |
5491 | return convert (type, build1 (NEGATE_EXPR, TREE_TYPE (targ0), targ0)); | |
fa8db1f7 | 5492 | |
b1a6f8db | 5493 | } |
6d716ca8 RS |
5494 | |
5495 | /* Convert - (a - b) to (b - a) for non-floating-point. */ | |
1baa375f | 5496 | else if (TREE_CODE (arg0) == MINUS_EXPR |
de6c5979 | 5497 | && (! FLOAT_TYPE_P (type) || flag_unsafe_math_optimizations)) |
6d716ca8 RS |
5498 | return build (MINUS_EXPR, type, TREE_OPERAND (arg0, 1), |
5499 | TREE_OPERAND (arg0, 0)); | |
5500 | ||
9f0a7f9d RS |
5501 | /* Convert -f(x) into f(-x) where f is sin, tan or atan. */ |
5502 | switch (builtin_mathfn_code (arg0)) | |
5503 | { | |
5504 | case BUILT_IN_SIN: | |
5505 | case BUILT_IN_SINF: | |
5506 | case BUILT_IN_SINL: | |
5507 | case BUILT_IN_TAN: | |
5508 | case BUILT_IN_TANF: | |
5509 | case BUILT_IN_TANL: | |
5510 | case BUILT_IN_ATAN: | |
5511 | case BUILT_IN_ATANF: | |
5512 | case BUILT_IN_ATANL: | |
5513 | if (negate_expr_p (TREE_VALUE (TREE_OPERAND (arg0, 1)))) | |
5514 | { | |
5515 | tree fndecl, arg, arglist; | |
5516 | ||
2f503025 | 5517 | fndecl = get_callee_fndecl (arg0); |
9f0a7f9d RS |
5518 | arg = TREE_VALUE (TREE_OPERAND (arg0, 1)); |
5519 | arg = fold (build1 (NEGATE_EXPR, type, arg)); | |
5520 | arglist = build_tree_list (NULL_TREE, arg); | |
5521 | return build_function_call_expr (fndecl, arglist); | |
5522 | } | |
5523 | break; | |
5524 | ||
5525 | default: | |
5526 | break; | |
5527 | } | |
6d716ca8 RS |
5528 | return t; |
5529 | ||
5530 | case ABS_EXPR: | |
5531 | if (wins) | |
5532 | { | |
5533 | if (TREE_CODE (arg0) == INTEGER_CST) | |
5534 | { | |
68e568c2 MM |
5535 | /* If the value is unsigned, then the absolute value is |
5536 | the same as the ordinary value. */ | |
5537 | if (TREE_UNSIGNED (type)) | |
5538 | return arg0; | |
5539 | /* Similarly, if the value is non-negative. */ | |
5540 | else if (INT_CST_LT (integer_minus_one_node, arg0)) | |
5541 | return arg0; | |
5542 | /* If the value is negative, then the absolute value is | |
5543 | its negation. */ | |
5544 | else | |
6d716ca8 | 5545 | { |
f9e158c3 JM |
5546 | unsigned HOST_WIDE_INT low; |
5547 | HOST_WIDE_INT high; | |
2a23183e RS |
5548 | int overflow = neg_double (TREE_INT_CST_LOW (arg0), |
5549 | TREE_INT_CST_HIGH (arg0), | |
5550 | &low, &high); | |
5551 | t = build_int_2 (low, high); | |
5552 | TREE_TYPE (t) = type; | |
dc3907c5 PE |
5553 | TREE_OVERFLOW (t) |
5554 | = (TREE_OVERFLOW (arg0) | |
e0f776fb | 5555 | | force_fit_type (t, overflow)); |
dc3907c5 PE |
5556 | TREE_CONSTANT_OVERFLOW (t) |
5557 | = TREE_OVERFLOW (t) | TREE_CONSTANT_OVERFLOW (arg0); | |
6d716ca8 RS |
5558 | } |
5559 | } | |
5560 | else if (TREE_CODE (arg0) == REAL_CST) | |
5561 | { | |
c05a9b68 | 5562 | if (REAL_VALUE_NEGATIVE (TREE_REAL_CST (arg0))) |
6d716ca8 RS |
5563 | t = build_real (type, |
5564 | REAL_VALUE_NEGATE (TREE_REAL_CST (arg0))); | |
5565 | } | |
6d716ca8 | 5566 | } |
07bae5ad RS |
5567 | else if (TREE_CODE (arg0) == NEGATE_EXPR) |
5568 | return fold (build1 (ABS_EXPR, type, TREE_OPERAND (arg0, 0))); | |
b1a6f8db JH |
5569 | /* Convert fabs((double)float) into (double)fabsf(float). */ |
5570 | else if (TREE_CODE (arg0) == NOP_EXPR | |
5571 | && TREE_CODE (type) == REAL_TYPE) | |
5572 | { | |
5573 | tree targ0 = strip_float_extensions (arg0); | |
5574 | if (targ0 != arg0) | |
07bae5ad RS |
5575 | return convert (type, fold (build1 (ABS_EXPR, TREE_TYPE (targ0), |
5576 | targ0))); | |
4977bab6 | 5577 | } |
07bae5ad RS |
5578 | else if (tree_expr_nonnegative_p (arg0)) |
5579 | return arg0; | |
6d716ca8 RS |
5580 | return t; |
5581 | ||
551064b1 RS |
5582 | case CONJ_EXPR: |
5583 | if (TREE_CODE (TREE_TYPE (arg0)) != COMPLEX_TYPE) | |
13eb1f7f | 5584 | return convert (type, arg0); |
551064b1 | 5585 | else if (TREE_CODE (arg0) == COMPLEX_EXPR) |
c9869b75 | 5586 | return build (COMPLEX_EXPR, type, |
551064b1 | 5587 | TREE_OPERAND (arg0, 0), |
1baa375f | 5588 | negate_expr (TREE_OPERAND (arg0, 1))); |
551064b1 | 5589 | else if (TREE_CODE (arg0) == COMPLEX_CST) |
32812a40 JM |
5590 | return build_complex (type, TREE_REALPART (arg0), |
5591 | negate_expr (TREE_IMAGPART (arg0))); | |
551064b1 RS |
5592 | else if (TREE_CODE (arg0) == PLUS_EXPR || TREE_CODE (arg0) == MINUS_EXPR) |
5593 | return fold (build (TREE_CODE (arg0), type, | |
5594 | fold (build1 (CONJ_EXPR, type, | |
5595 | TREE_OPERAND (arg0, 0))), | |
5596 | fold (build1 (CONJ_EXPR, | |
5597 | type, TREE_OPERAND (arg0, 1))))); | |
5598 | else if (TREE_CODE (arg0) == CONJ_EXPR) | |
5599 | return TREE_OPERAND (arg0, 0); | |
5600 | return t; | |
5601 | ||
6d716ca8 RS |
5602 | case BIT_NOT_EXPR: |
5603 | if (wins) | |
5604 | { | |
380ff34a RK |
5605 | t = build_int_2 (~ TREE_INT_CST_LOW (arg0), |
5606 | ~ TREE_INT_CST_HIGH (arg0)); | |
6d716ca8 | 5607 | TREE_TYPE (t) = type; |
e0f776fb | 5608 | force_fit_type (t, 0); |
dc3907c5 | 5609 | TREE_OVERFLOW (t) = TREE_OVERFLOW (arg0); |
fe3e8e40 | 5610 | TREE_CONSTANT_OVERFLOW (t) = TREE_CONSTANT_OVERFLOW (arg0); |
6d716ca8 RS |
5611 | } |
5612 | else if (TREE_CODE (arg0) == BIT_NOT_EXPR) | |
5613 | return TREE_OPERAND (arg0, 0); | |
5614 | return t; | |
5615 | ||
5616 | case PLUS_EXPR: | |
5617 | /* A + (-B) -> A - B */ | |
5618 | if (TREE_CODE (arg1) == NEGATE_EXPR) | |
5619 | return fold (build (MINUS_EXPR, type, arg0, TREE_OPERAND (arg1, 0))); | |
10414089 JL |
5620 | /* (-A) + B -> B - A */ |
5621 | if (TREE_CODE (arg0) == NEGATE_EXPR) | |
5622 | return fold (build (MINUS_EXPR, type, arg1, TREE_OPERAND (arg0, 0))); | |
7178e3af | 5623 | else if (! FLOAT_TYPE_P (type)) |
6d716ca8 RS |
5624 | { |
5625 | if (integer_zerop (arg1)) | |
5626 | return non_lvalue (convert (type, arg0)); | |
5627 | ||
5628 | /* If we are adding two BIT_AND_EXPR's, both of which are and'ing | |
5629 | with a constant, and the two constants have no bits in common, | |
5630 | we should treat this as a BIT_IOR_EXPR since this may produce more | |
5631 | simplifications. */ | |
5632 | if (TREE_CODE (arg0) == BIT_AND_EXPR | |
5633 | && TREE_CODE (arg1) == BIT_AND_EXPR | |
5634 | && TREE_CODE (TREE_OPERAND (arg0, 1)) == INTEGER_CST | |
5635 | && TREE_CODE (TREE_OPERAND (arg1, 1)) == INTEGER_CST | |
5636 | && integer_zerop (const_binop (BIT_AND_EXPR, | |
5637 | TREE_OPERAND (arg0, 1), | |
91d33e36 | 5638 | TREE_OPERAND (arg1, 1), 0))) |
6d716ca8 RS |
5639 | { |
5640 | code = BIT_IOR_EXPR; | |
5641 | goto bit_ior; | |
5642 | } | |
6a96fcb4 | 5643 | |
abe4f192 | 5644 | /* Reassociate (plus (plus (mult) (foo)) (mult)) as |
b6cc0a72 | 5645 | (plus (plus (mult) (mult)) (foo)) so that we can |
abe4f192 RH |
5646 | take advantage of the factoring cases below. */ |
5647 | if ((TREE_CODE (arg0) == PLUS_EXPR | |
5648 | && TREE_CODE (arg1) == MULT_EXPR) | |
5649 | || (TREE_CODE (arg1) == PLUS_EXPR | |
b6cc0a72 | 5650 | && TREE_CODE (arg0) == MULT_EXPR)) |
abe4f192 RH |
5651 | { |
5652 | tree parg0, parg1, parg, marg; | |
5653 | ||
5654 | if (TREE_CODE (arg0) == PLUS_EXPR) | |
5655 | parg = arg0, marg = arg1; | |
5656 | else | |
5657 | parg = arg1, marg = arg0; | |
5658 | parg0 = TREE_OPERAND (parg, 0); | |
5659 | parg1 = TREE_OPERAND (parg, 1); | |
5660 | STRIP_NOPS (parg0); | |
5661 | STRIP_NOPS (parg1); | |
5662 | ||
5663 | if (TREE_CODE (parg0) == MULT_EXPR | |
5664 | && TREE_CODE (parg1) != MULT_EXPR) | |
5665 | return fold (build (PLUS_EXPR, type, | |
fa8db1f7 AJ |
5666 | fold (build (PLUS_EXPR, type, |
5667 | convert (type, parg0), | |
3cd58fd7 OH |
5668 | convert (type, marg))), |
5669 | convert (type, parg1))); | |
abe4f192 RH |
5670 | if (TREE_CODE (parg0) != MULT_EXPR |
5671 | && TREE_CODE (parg1) == MULT_EXPR) | |
5672 | return fold (build (PLUS_EXPR, type, | |
fa8db1f7 AJ |
5673 | fold (build (PLUS_EXPR, type, |
5674 | convert (type, parg1), | |
3cd58fd7 OH |
5675 | convert (type, marg))), |
5676 | convert (type, parg0))); | |
abe4f192 RH |
5677 | } |
5678 | ||
45f97e2e RH |
5679 | if (TREE_CODE (arg0) == MULT_EXPR && TREE_CODE (arg1) == MULT_EXPR) |
5680 | { | |
5681 | tree arg00, arg01, arg10, arg11; | |
07444f1d | 5682 | tree alt0 = NULL_TREE, alt1 = NULL_TREE, same; |
45f97e2e RH |
5683 | |
5684 | /* (A * C) + (B * C) -> (A+B) * C. | |
5685 | We are most concerned about the case where C is a constant, | |
5686 | but other combinations show up during loop reduction. Since | |
5687 | it is not difficult, try all four possibilities. */ | |
5688 | ||
5689 | arg00 = TREE_OPERAND (arg0, 0); | |
5690 | arg01 = TREE_OPERAND (arg0, 1); | |
5691 | arg10 = TREE_OPERAND (arg1, 0); | |
5692 | arg11 = TREE_OPERAND (arg1, 1); | |
5693 | same = NULL_TREE; | |
5694 | ||
5695 | if (operand_equal_p (arg01, arg11, 0)) | |
5696 | same = arg01, alt0 = arg00, alt1 = arg10; | |
5697 | else if (operand_equal_p (arg00, arg10, 0)) | |
5698 | same = arg00, alt0 = arg01, alt1 = arg11; | |
5699 | else if (operand_equal_p (arg00, arg11, 0)) | |
5700 | same = arg00, alt0 = arg01, alt1 = arg10; | |
5701 | else if (operand_equal_p (arg01, arg10, 0)) | |
5702 | same = arg01, alt0 = arg00, alt1 = arg11; | |
5703 | ||
abe4f192 RH |
5704 | /* No identical multiplicands; see if we can find a common |
5705 | power-of-two factor in non-power-of-two multiplies. This | |
5706 | can help in multi-dimensional array access. */ | |
5707 | else if (TREE_CODE (arg01) == INTEGER_CST | |
5708 | && TREE_CODE (arg11) == INTEGER_CST | |
5709 | && TREE_INT_CST_HIGH (arg01) == 0 | |
5710 | && TREE_INT_CST_HIGH (arg11) == 0) | |
5711 | { | |
5712 | HOST_WIDE_INT int01, int11, tmp; | |
5713 | int01 = TREE_INT_CST_LOW (arg01); | |
5714 | int11 = TREE_INT_CST_LOW (arg11); | |
5715 | ||
5716 | /* Move min of absolute values to int11. */ | |
5717 | if ((int01 >= 0 ? int01 : -int01) | |
5718 | < (int11 >= 0 ? int11 : -int11)) | |
5719 | { | |
5720 | tmp = int01, int01 = int11, int11 = tmp; | |
5721 | alt0 = arg00, arg00 = arg10, arg10 = alt0; | |
5722 | alt0 = arg01, arg01 = arg11, arg11 = alt0; | |
5723 | } | |
5724 | ||
5725 | if (exact_log2 (int11) > 0 && int01 % int11 == 0) | |
5726 | { | |
5727 | alt0 = fold (build (MULT_EXPR, type, arg00, | |
5728 | build_int_2 (int01 / int11, 0))); | |
5729 | alt1 = arg10; | |
5730 | same = arg11; | |
5731 | } | |
5732 | } | |
5733 | ||
45f97e2e | 5734 | if (same) |
b6cc0a72 | 5735 | return fold (build (MULT_EXPR, type, |
45f97e2e RH |
5736 | fold (build (PLUS_EXPR, type, alt0, alt1)), |
5737 | same)); | |
5738 | } | |
6d716ca8 | 5739 | } |
f2593a66 RS |
5740 | else |
5741 | { | |
5742 | /* See if ARG1 is zero and X + ARG1 reduces to X. */ | |
5743 | if (fold_real_zero_addition_p (TREE_TYPE (arg0), arg1, 0)) | |
5744 | return non_lvalue (convert (type, arg0)); | |
71925bc0 | 5745 | |
f2593a66 RS |
5746 | /* Likewise if the operands are reversed. */ |
5747 | if (fold_real_zero_addition_p (TREE_TYPE (arg1), arg0, 0)) | |
5748 | return non_lvalue (convert (type, arg1)); | |
5749 | ||
5750 | /* Convert x+x into x*2.0. */ | |
00229de4 RS |
5751 | if (operand_equal_p (arg0, arg1, 0) |
5752 | && SCALAR_FLOAT_TYPE_P (type)) | |
f2593a66 RS |
5753 | return fold (build (MULT_EXPR, type, arg0, |
5754 | build_real (type, dconst2))); | |
5755 | ||
5756 | /* Convert x*c+x into x*(c+1). */ | |
5757 | if (flag_unsafe_math_optimizations | |
5758 | && TREE_CODE (arg0) == MULT_EXPR | |
5759 | && TREE_CODE (TREE_OPERAND (arg0, 1)) == REAL_CST | |
5760 | && ! TREE_CONSTANT_OVERFLOW (TREE_OPERAND (arg0, 1)) | |
5761 | && operand_equal_p (TREE_OPERAND (arg0, 0), arg1, 0)) | |
5762 | { | |
5763 | REAL_VALUE_TYPE c; | |
5764 | ||
5765 | c = TREE_REAL_CST (TREE_OPERAND (arg0, 1)); | |
5766 | real_arithmetic (&c, PLUS_EXPR, &c, &dconst1); | |
5767 | return fold (build (MULT_EXPR, type, arg1, | |
5768 | build_real (type, c))); | |
5769 | } | |
5770 | ||
5771 | /* Convert x+x*c into x*(c+1). */ | |
5772 | if (flag_unsafe_math_optimizations | |
5773 | && TREE_CODE (arg1) == MULT_EXPR | |
5774 | && TREE_CODE (TREE_OPERAND (arg1, 1)) == REAL_CST | |
5775 | && ! TREE_CONSTANT_OVERFLOW (TREE_OPERAND (arg1, 1)) | |
5776 | && operand_equal_p (TREE_OPERAND (arg1, 0), arg0, 0)) | |
5777 | { | |
5778 | REAL_VALUE_TYPE c; | |
10414089 | 5779 | |
f2593a66 RS |
5780 | c = TREE_REAL_CST (TREE_OPERAND (arg1, 1)); |
5781 | real_arithmetic (&c, PLUS_EXPR, &c, &dconst1); | |
5782 | return fold (build (MULT_EXPR, type, arg0, | |
5783 | build_real (type, c))); | |
5784 | } | |
5785 | ||
5786 | /* Convert x*c1+x*c2 into x*(c1+c2). */ | |
5787 | if (flag_unsafe_math_optimizations | |
5788 | && TREE_CODE (arg0) == MULT_EXPR | |
5789 | && TREE_CODE (arg1) == MULT_EXPR | |
5790 | && TREE_CODE (TREE_OPERAND (arg0, 1)) == REAL_CST | |
5791 | && ! TREE_CONSTANT_OVERFLOW (TREE_OPERAND (arg0, 1)) | |
5792 | && TREE_CODE (TREE_OPERAND (arg1, 1)) == REAL_CST | |
5793 | && ! TREE_CONSTANT_OVERFLOW (TREE_OPERAND (arg1, 1)) | |
5794 | && operand_equal_p (TREE_OPERAND (arg0, 0), | |
5795 | TREE_OPERAND (arg1, 0), 0)) | |
5796 | { | |
5797 | REAL_VALUE_TYPE c1, c2; | |
5798 | ||
5799 | c1 = TREE_REAL_CST (TREE_OPERAND (arg0, 1)); | |
5800 | c2 = TREE_REAL_CST (TREE_OPERAND (arg1, 1)); | |
5801 | real_arithmetic (&c1, PLUS_EXPR, &c1, &c2); | |
5802 | return fold (build (MULT_EXPR, type, | |
5803 | TREE_OPERAND (arg0, 0), | |
5804 | build_real (type, c1))); | |
5805 | } | |
5806 | } | |
71925bc0 | 5807 | |
79e8185c JH |
5808 | bit_rotate: |
5809 | /* (A << C1) + (A >> C2) if A is unsigned and C1+C2 is the size of A | |
5810 | is a rotate of A by C1 bits. */ | |
5811 | /* (A << B) + (A >> (Z - B)) if A is unsigned and Z is the size of A | |
5812 | is a rotate of A by B bits. */ | |
5813 | { | |
b3694847 | 5814 | enum tree_code code0, code1; |
b6cc0a72 KH |
5815 | code0 = TREE_CODE (arg0); |
5816 | code1 = TREE_CODE (arg1); | |
5817 | if (((code0 == RSHIFT_EXPR && code1 == LSHIFT_EXPR) | |
5818 | || (code1 == RSHIFT_EXPR && code0 == LSHIFT_EXPR)) | |
79e8185c | 5819 | && operand_equal_p (TREE_OPERAND (arg0, 0), |
b6cc0a72 | 5820 | TREE_OPERAND (arg1, 0), 0) |
79e8185c JH |
5821 | && TREE_UNSIGNED (TREE_TYPE (TREE_OPERAND (arg0, 0)))) |
5822 | { | |
b3694847 SS |
5823 | tree tree01, tree11; |
5824 | enum tree_code code01, code11; | |
79e8185c JH |
5825 | |
5826 | tree01 = TREE_OPERAND (arg0, 1); | |
5827 | tree11 = TREE_OPERAND (arg1, 1); | |
5828 | STRIP_NOPS (tree01); | |
5829 | STRIP_NOPS (tree11); | |
5830 | code01 = TREE_CODE (tree01); | |
5831 | code11 = TREE_CODE (tree11); | |
5832 | if (code01 == INTEGER_CST | |
b6cc0a72 KH |
5833 | && code11 == INTEGER_CST |
5834 | && TREE_INT_CST_HIGH (tree01) == 0 | |
5835 | && TREE_INT_CST_HIGH (tree11) == 0 | |
5836 | && ((TREE_INT_CST_LOW (tree01) + TREE_INT_CST_LOW (tree11)) | |
5837 | == TYPE_PRECISION (TREE_TYPE (TREE_OPERAND (arg0, 0))))) | |
79e8185c | 5838 | return build (LROTATE_EXPR, type, TREE_OPERAND (arg0, 0), |
b6cc0a72 | 5839 | code0 == LSHIFT_EXPR ? tree01 : tree11); |
79e8185c JH |
5840 | else if (code11 == MINUS_EXPR) |
5841 | { | |
b6cc0a72 KH |
5842 | tree tree110, tree111; |
5843 | tree110 = TREE_OPERAND (tree11, 0); | |
5844 | tree111 = TREE_OPERAND (tree11, 1); | |
5845 | STRIP_NOPS (tree110); | |
5846 | STRIP_NOPS (tree111); | |
5847 | if (TREE_CODE (tree110) == INTEGER_CST | |
05bccae2 RK |
5848 | && 0 == compare_tree_int (tree110, |
5849 | TYPE_PRECISION | |
5850 | (TREE_TYPE (TREE_OPERAND | |
5851 | (arg0, 0)))) | |
79e8185c | 5852 | && operand_equal_p (tree01, tree111, 0)) |
b6cc0a72 KH |
5853 | return build ((code0 == LSHIFT_EXPR |
5854 | ? LROTATE_EXPR | |
5855 | : RROTATE_EXPR), | |
5856 | type, TREE_OPERAND (arg0, 0), tree01); | |
79e8185c JH |
5857 | } |
5858 | else if (code01 == MINUS_EXPR) | |
5859 | { | |
b6cc0a72 KH |
5860 | tree tree010, tree011; |
5861 | tree010 = TREE_OPERAND (tree01, 0); | |
5862 | tree011 = TREE_OPERAND (tree01, 1); | |
5863 | STRIP_NOPS (tree010); | |
5864 | STRIP_NOPS (tree011); | |
5865 | if (TREE_CODE (tree010) == INTEGER_CST | |
05bccae2 RK |
5866 | && 0 == compare_tree_int (tree010, |
5867 | TYPE_PRECISION | |
5868 | (TREE_TYPE (TREE_OPERAND | |
5869 | (arg0, 0)))) | |
79e8185c | 5870 | && operand_equal_p (tree11, tree011, 0)) |
b6cc0a72 KH |
5871 | return build ((code0 != LSHIFT_EXPR |
5872 | ? LROTATE_EXPR | |
5873 | : RROTATE_EXPR), | |
5874 | type, TREE_OPERAND (arg0, 0), tree11); | |
79e8185c JH |
5875 | } |
5876 | } | |
5877 | } | |
10414089 | 5878 | |
6d716ca8 | 5879 | associate: |
1baa375f RK |
5880 | /* In most languages, can't associate operations on floats through |
5881 | parentheses. Rather than remember where the parentheses were, we | |
af7b5c1c RS |
5882 | don't associate floats at all, unless the user has specified |
5883 | -funsafe-math-optimizations. */ | |
1baa375f RK |
5884 | |
5885 | if (! wins | |
af7b5c1c | 5886 | && (! FLOAT_TYPE_P (type) || flag_unsafe_math_optimizations)) |
6d716ca8 | 5887 | { |
cff27795 EB |
5888 | tree var0, con0, lit0, minus_lit0; |
5889 | tree var1, con1, lit1, minus_lit1; | |
1baa375f RK |
5890 | |
5891 | /* Split both trees into variables, constants, and literals. Then | |
5892 | associate each group together, the constants with literals, | |
5893 | then the result with variables. This increases the chances of | |
5894 | literals being recombined later and of generating relocatable | |
30f7a378 | 5895 | expressions for the sum of a constant and literal. */ |
cff27795 EB |
5896 | var0 = split_tree (arg0, code, &con0, &lit0, &minus_lit0, 0); |
5897 | var1 = split_tree (arg1, code, &con1, &lit1, &minus_lit1, | |
5898 | code == MINUS_EXPR); | |
1baa375f RK |
5899 | |
5900 | /* Only do something if we found more than two objects. Otherwise, | |
5901 | nothing has changed and we risk infinite recursion. */ | |
cff27795 EB |
5902 | if (2 < ((var0 != 0) + (var1 != 0) |
5903 | + (con0 != 0) + (con1 != 0) | |
5904 | + (lit0 != 0) + (lit1 != 0) | |
5905 | + (minus_lit0 != 0) + (minus_lit1 != 0))) | |
6d716ca8 | 5906 | { |
cff27795 EB |
5907 | /* Recombine MINUS_EXPR operands by using PLUS_EXPR. */ |
5908 | if (code == MINUS_EXPR) | |
5909 | code = PLUS_EXPR; | |
5910 | ||
1baa375f RK |
5911 | var0 = associate_trees (var0, var1, code, type); |
5912 | con0 = associate_trees (con0, con1, code, type); | |
5913 | lit0 = associate_trees (lit0, lit1, code, type); | |
cff27795 EB |
5914 | minus_lit0 = associate_trees (minus_lit0, minus_lit1, code, type); |
5915 | ||
5916 | /* Preserve the MINUS_EXPR if the negative part of the literal is | |
5917 | greater than the positive part. Otherwise, the multiplicative | |
5918 | folding code (i.e extract_muldiv) may be fooled in case | |
e0bb17a8 | 5919 | unsigned constants are subtracted, like in the following |
cff27795 EB |
5920 | example: ((X*2 + 4) - 8U)/2. */ |
5921 | if (minus_lit0 && lit0) | |
5922 | { | |
2cf099a5 RS |
5923 | if (TREE_CODE (lit0) == INTEGER_CST |
5924 | && TREE_CODE (minus_lit0) == INTEGER_CST | |
5925 | && tree_int_cst_lt (lit0, minus_lit0)) | |
cff27795 EB |
5926 | { |
5927 | minus_lit0 = associate_trees (minus_lit0, lit0, | |
5928 | MINUS_EXPR, type); | |
5929 | lit0 = 0; | |
5930 | } | |
5931 | else | |
5932 | { | |
5933 | lit0 = associate_trees (lit0, minus_lit0, | |
5934 | MINUS_EXPR, type); | |
5935 | minus_lit0 = 0; | |
5936 | } | |
5937 | } | |
5938 | if (minus_lit0) | |
5939 | { | |
5940 | if (con0 == 0) | |
5941 | return convert (type, associate_trees (var0, minus_lit0, | |
5942 | MINUS_EXPR, type)); | |
5943 | else | |
5944 | { | |
5945 | con0 = associate_trees (con0, minus_lit0, | |
5946 | MINUS_EXPR, type); | |
5947 | return convert (type, associate_trees (var0, con0, | |
5948 | PLUS_EXPR, type)); | |
5949 | } | |
5950 | } | |
5951 | ||
1baa375f RK |
5952 | con0 = associate_trees (con0, lit0, code, type); |
5953 | return convert (type, associate_trees (var0, con0, code, type)); | |
6d716ca8 RS |
5954 | } |
5955 | } | |
1baa375f | 5956 | |
6d716ca8 | 5957 | binary: |
6d716ca8 | 5958 | if (wins) |
91d33e36 | 5959 | t1 = const_binop (code, arg0, arg1, 0); |
6d716ca8 RS |
5960 | if (t1 != NULL_TREE) |
5961 | { | |
5962 | /* The return value should always have | |
5963 | the same type as the original expression. */ | |
380ff34a RK |
5964 | if (TREE_TYPE (t1) != TREE_TYPE (t)) |
5965 | t1 = convert (TREE_TYPE (t), t1); | |
5966 | ||
6d716ca8 RS |
5967 | return t1; |
5968 | } | |
5969 | return t; | |
5970 | ||
5971 | case MINUS_EXPR: | |
10414089 JL |
5972 | /* A - (-B) -> A + B */ |
5973 | if (TREE_CODE (arg1) == NEGATE_EXPR) | |
5974 | return fold (build (PLUS_EXPR, type, arg0, TREE_OPERAND (arg1, 0))); | |
080ea642 RS |
5975 | /* (-A) - B -> (-B) - A where B is easily negated and we can swap. */ |
5976 | if (TREE_CODE (arg0) == NEGATE_EXPR | |
4fa26a60 RS |
5977 | && (FLOAT_TYPE_P (type) |
5978 | || (INTEGRAL_TYPE_P (type) && flag_wrapv && !flag_trapv)) | |
080ea642 RS |
5979 | && negate_expr_p (arg1) |
5980 | && (! TREE_SIDE_EFFECTS (arg0) || TREE_CONSTANT (arg1)) | |
5981 | && (! TREE_SIDE_EFFECTS (arg1) || TREE_CONSTANT (arg0))) | |
5982 | return fold (build (MINUS_EXPR, type, negate_expr (arg1), | |
5983 | TREE_OPERAND (arg0, 0))); | |
10414089 | 5984 | |
7178e3af | 5985 | if (! FLOAT_TYPE_P (type)) |
6d716ca8 RS |
5986 | { |
5987 | if (! wins && integer_zerop (arg0)) | |
b8fbe62c | 5988 | return negate_expr (convert (type, arg1)); |
6d716ca8 RS |
5989 | if (integer_zerop (arg1)) |
5990 | return non_lvalue (convert (type, arg0)); | |
6a96fcb4 RK |
5991 | |
5992 | /* (A * C) - (B * C) -> (A-B) * C. Since we are most concerned | |
5993 | about the case where C is a constant, just try one of the | |
5994 | four possibilities. */ | |
5995 | ||
5996 | if (TREE_CODE (arg0) == MULT_EXPR && TREE_CODE (arg1) == MULT_EXPR | |
5997 | && operand_equal_p (TREE_OPERAND (arg0, 1), | |
5998 | TREE_OPERAND (arg1, 1), 0)) | |
5999 | return fold (build (MULT_EXPR, type, | |
6000 | fold (build (MINUS_EXPR, type, | |
6001 | TREE_OPERAND (arg0, 0), | |
6002 | TREE_OPERAND (arg1, 0))), | |
6003 | TREE_OPERAND (arg0, 1))); | |
015c3186 KH |
6004 | |
6005 | /* Fold A - (A & B) into ~B & A. */ | |
6006 | if (!TREE_SIDE_EFFECTS (arg0) | |
6007 | && TREE_CODE (arg1) == BIT_AND_EXPR) | |
6008 | { | |
6009 | if (operand_equal_p (arg0, TREE_OPERAND (arg1, 1), 0)) | |
6010 | return fold (build (BIT_AND_EXPR, type, | |
6011 | fold (build1 (BIT_NOT_EXPR, type, | |
6012 | TREE_OPERAND (arg1, 0))), | |
6013 | arg0)); | |
6014 | if (operand_equal_p (arg0, TREE_OPERAND (arg1, 0), 0)) | |
6015 | return fold (build (BIT_AND_EXPR, type, | |
6016 | fold (build1 (BIT_NOT_EXPR, type, | |
6017 | TREE_OPERAND (arg1, 1))), | |
6018 | arg0)); | |
6019 | } | |
38b35623 KH |
6020 | |
6021 | /* Fold (A & ~B) - (A & B) into (A ^ B) - B, , where B is | |
6022 | any power of 2 minus 1. */ | |
6023 | if (TREE_CODE (arg0) == BIT_AND_EXPR | |
6024 | && TREE_CODE (arg1) == BIT_AND_EXPR | |
6025 | && operand_equal_p (TREE_OPERAND (arg0, 0), | |
6026 | TREE_OPERAND (arg1, 0), 0) | |
6027 | && TREE_CODE (TREE_OPERAND (arg0, 1)) == INTEGER_CST | |
6028 | && TREE_CODE (TREE_OPERAND (arg1, 1)) == INTEGER_CST) | |
6029 | { | |
6030 | tree mask0 = TREE_OPERAND (arg0, 1); | |
6031 | tree mask1 = TREE_OPERAND (arg1, 1); | |
6032 | tree tem = fold (build1 (BIT_NOT_EXPR, type, mask0)); | |
6033 | ||
6034 | if (operand_equal_p (tem, mask1, 0) | |
6035 | && integer_pow2p (fold (build (PLUS_EXPR, type, | |
6036 | mask1, integer_one_node)))) | |
6037 | { | |
6038 | tem = fold (build (BIT_XOR_EXPR, type, | |
6039 | TREE_OPERAND (arg0, 0), mask1)); | |
6040 | return fold (build (MINUS_EXPR, type, tem, mask1)); | |
6041 | } | |
6042 | } | |
6d716ca8 | 6043 | } |
fab446b8 | 6044 | |
71925bc0 RS |
6045 | /* See if ARG1 is zero and X - ARG1 reduces to X. */ |
6046 | else if (fold_real_zero_addition_p (TREE_TYPE (arg0), arg1, 1)) | |
6047 | return non_lvalue (convert (type, arg0)); | |
6048 | ||
6049 | /* (ARG0 - ARG1) is the same as (-ARG1 + ARG0). So check whether | |
6050 | ARG0 is zero and X + ARG0 reduces to X, since that would mean | |
6051 | (-ARG1 + ARG0) reduces to -ARG1. */ | |
6052 | else if (!wins && fold_real_zero_addition_p (TREE_TYPE (arg1), arg0, 0)) | |
6053 | return negate_expr (convert (type, arg1)); | |
a6acbe15 | 6054 | |
b6cc0a72 | 6055 | /* Fold &x - &x. This can happen from &x.foo - &x. |
fab446b8 RK |
6056 | This is unsafe for certain floats even in non-IEEE formats. |
6057 | In IEEE, it is unsafe because it does wrong for NaNs. | |
6058 | Also note that operand_equal_p is always false if an operand | |
6059 | is volatile. */ | |
6060 | ||
de6c5979 | 6061 | if ((! FLOAT_TYPE_P (type) || flag_unsafe_math_optimizations) |
59d90212 | 6062 | && operand_equal_p (arg0, arg1, 0)) |
fab446b8 | 6063 | return convert (type, integer_zero_node); |
a6acbe15 | 6064 | |
6d716ca8 RS |
6065 | goto associate; |
6066 | ||
6067 | case MULT_EXPR: | |
10414089 | 6068 | /* (-A) * (-B) -> A * B */ |
8ab49fef RS |
6069 | if (TREE_CODE (arg0) == NEGATE_EXPR && negate_expr_p (arg1)) |
6070 | return fold (build (MULT_EXPR, type, | |
6071 | TREE_OPERAND (arg0, 0), | |
6072 | negate_expr (arg1))); | |
6073 | if (TREE_CODE (arg1) == NEGATE_EXPR && negate_expr_p (arg0)) | |
6074 | return fold (build (MULT_EXPR, type, | |
6075 | negate_expr (arg0), | |
b6cc0a72 | 6076 | TREE_OPERAND (arg1, 0))); |
10414089 | 6077 | |
7178e3af | 6078 | if (! FLOAT_TYPE_P (type)) |
6d716ca8 RS |
6079 | { |
6080 | if (integer_zerop (arg1)) | |
6081 | return omit_one_operand (type, arg1, arg0); | |
6082 | if (integer_onep (arg1)) | |
6083 | return non_lvalue (convert (type, arg0)); | |
6084 | ||
6085 | /* (a * (1 << b)) is (a << b) */ | |
6086 | if (TREE_CODE (arg1) == LSHIFT_EXPR | |
6087 | && integer_onep (TREE_OPERAND (arg1, 0))) | |
6088 | return fold (build (LSHIFT_EXPR, type, arg0, | |
6089 | TREE_OPERAND (arg1, 1))); | |
6090 | if (TREE_CODE (arg0) == LSHIFT_EXPR | |
6091 | && integer_onep (TREE_OPERAND (arg0, 0))) | |
6092 | return fold (build (LSHIFT_EXPR, type, arg1, | |
6093 | TREE_OPERAND (arg0, 1))); | |
1baa375f RK |
6094 | |
6095 | if (TREE_CODE (arg1) == INTEGER_CST | |
3cd58fd7 OH |
6096 | && 0 != (tem = extract_muldiv (TREE_OPERAND (t, 0), |
6097 | convert (type, arg1), | |
1baa375f RK |
6098 | code, NULL_TREE))) |
6099 | return convert (type, tem); | |
6100 | ||
6d716ca8 | 6101 | } |
6d716ca8 RS |
6102 | else |
6103 | { | |
71925bc0 RS |
6104 | /* Maybe fold x * 0 to 0. The expressions aren't the same |
6105 | when x is NaN, since x * 0 is also NaN. Nor are they the | |
6106 | same in modes with signed zeros, since multiplying a | |
6107 | negative value by 0 gives -0, not +0. */ | |
6108 | if (!HONOR_NANS (TYPE_MODE (TREE_TYPE (arg0))) | |
6109 | && !HONOR_SIGNED_ZEROS (TYPE_MODE (TREE_TYPE (arg0))) | |
6d716ca8 RS |
6110 | && real_zerop (arg1)) |
6111 | return omit_one_operand (type, arg1, arg0); | |
52bfebf0 RS |
6112 | /* In IEEE floating point, x*1 is not equivalent to x for snans. */ |
6113 | if (!HONOR_SNANS (TYPE_MODE (TREE_TYPE (arg0))) | |
6114 | && real_onep (arg1)) | |
6d716ca8 | 6115 | return non_lvalue (convert (type, arg0)); |
378393da | 6116 | |
52bfebf0 RS |
6117 | /* Transform x * -1.0 into -x. */ |
6118 | if (!HONOR_SNANS (TYPE_MODE (TREE_TYPE (arg0))) | |
378393da RS |
6119 | && real_minus_onep (arg1)) |
6120 | return fold (build1 (NEGATE_EXPR, type, arg0)); | |
6121 | ||
e3232933 RS |
6122 | /* Convert (C1/X)*C2 into (C1*C2)/X. */ |
6123 | if (flag_unsafe_math_optimizations | |
6124 | && TREE_CODE (arg0) == RDIV_EXPR | |
6125 | && TREE_CODE (arg1) == REAL_CST | |
6126 | && TREE_CODE (TREE_OPERAND (arg0, 0)) == REAL_CST) | |
6127 | { | |
6128 | tree tem = const_binop (MULT_EXPR, TREE_OPERAND (arg0, 0), | |
6129 | arg1, 0); | |
6130 | if (tem) | |
6131 | return fold (build (RDIV_EXPR, type, tem, | |
6132 | TREE_OPERAND (arg0, 1))); | |
6133 | } | |
6134 | ||
4977bab6 ZW |
6135 | if (flag_unsafe_math_optimizations) |
6136 | { | |
6137 | enum built_in_function fcode0 = builtin_mathfn_code (arg0); | |
6138 | enum built_in_function fcode1 = builtin_mathfn_code (arg1); | |
6139 | ||
5fce2c65 | 6140 | /* Optimizations of sqrt(...)*sqrt(...). */ |
4977bab6 ZW |
6141 | if ((fcode0 == BUILT_IN_SQRT && fcode1 == BUILT_IN_SQRT) |
6142 | || (fcode0 == BUILT_IN_SQRTF && fcode1 == BUILT_IN_SQRTF) | |
6143 | || (fcode0 == BUILT_IN_SQRTL && fcode1 == BUILT_IN_SQRTL)) | |
6144 | { | |
5fce2c65 RS |
6145 | tree sqrtfn, arg, arglist; |
6146 | tree arg00 = TREE_VALUE (TREE_OPERAND (arg0, 1)); | |
6147 | tree arg10 = TREE_VALUE (TREE_OPERAND (arg1, 1)); | |
6148 | ||
6149 | /* Optimize sqrt(x)*sqrt(x) as x. */ | |
6150 | if (operand_equal_p (arg00, arg10, 0) | |
6151 | && ! HONOR_SNANS (TYPE_MODE (type))) | |
6152 | return arg00; | |
6153 | ||
6154 | /* Optimize sqrt(x)*sqrt(y) as sqrt(x*y). */ | |
6155 | sqrtfn = TREE_OPERAND (TREE_OPERAND (arg0, 0), 0); | |
6156 | arg = fold (build (MULT_EXPR, type, arg00, arg10)); | |
6157 | arglist = build_tree_list (NULL_TREE, arg); | |
6158 | return build_function_call_expr (sqrtfn, arglist); | |
4977bab6 ZW |
6159 | } |
6160 | ||
f7657db9 KG |
6161 | /* Optimize expN(x)*expN(y) as expN(x+y). */ |
6162 | if (fcode0 == fcode1 | |
6163 | && (fcode0 == BUILT_IN_EXP | |
6164 | || fcode0 == BUILT_IN_EXPF | |
6165 | || fcode0 == BUILT_IN_EXPL | |
6166 | || fcode0 == BUILT_IN_EXP2 | |
6167 | || fcode0 == BUILT_IN_EXP2F | |
6168 | || fcode0 == BUILT_IN_EXP2L | |
6169 | || fcode0 == BUILT_IN_EXP10 | |
6170 | || fcode0 == BUILT_IN_EXP10F | |
6171 | || fcode0 == BUILT_IN_EXP10L | |
6172 | || fcode0 == BUILT_IN_POW10 | |
6173 | || fcode0 == BUILT_IN_POW10F | |
6174 | || fcode0 == BUILT_IN_POW10L)) | |
4977bab6 ZW |
6175 | { |
6176 | tree expfn = TREE_OPERAND (TREE_OPERAND (arg0, 0), 0); | |
6177 | tree arg = build (PLUS_EXPR, type, | |
6178 | TREE_VALUE (TREE_OPERAND (arg0, 1)), | |
6179 | TREE_VALUE (TREE_OPERAND (arg1, 1))); | |
5fce2c65 RS |
6180 | tree arglist = build_tree_list (NULL_TREE, fold (arg)); |
6181 | return build_function_call_expr (expfn, arglist); | |
6182 | } | |
6183 | ||
6184 | /* Optimizations of pow(...)*pow(...). */ | |
6185 | if ((fcode0 == BUILT_IN_POW && fcode1 == BUILT_IN_POW) | |
6186 | || (fcode0 == BUILT_IN_POWF && fcode1 == BUILT_IN_POWF) | |
6187 | || (fcode0 == BUILT_IN_POWL && fcode1 == BUILT_IN_POWL)) | |
6188 | { | |
6189 | tree arg00 = TREE_VALUE (TREE_OPERAND (arg0, 1)); | |
6190 | tree arg01 = TREE_VALUE (TREE_CHAIN (TREE_OPERAND (arg0, | |
6191 | 1))); | |
6192 | tree arg10 = TREE_VALUE (TREE_OPERAND (arg1, 1)); | |
6193 | tree arg11 = TREE_VALUE (TREE_CHAIN (TREE_OPERAND (arg1, | |
6194 | 1))); | |
6195 | ||
6196 | /* Optimize pow(x,y)*pow(z,y) as pow(x*z,y). */ | |
6197 | if (operand_equal_p (arg01, arg11, 0)) | |
6198 | { | |
6199 | tree powfn = TREE_OPERAND (TREE_OPERAND (arg0, 0), 0); | |
6200 | tree arg = build (MULT_EXPR, type, arg00, arg10); | |
6201 | tree arglist = tree_cons (NULL_TREE, fold (arg), | |
6202 | build_tree_list (NULL_TREE, | |
6203 | arg01)); | |
6204 | return build_function_call_expr (powfn, arglist); | |
6205 | } | |
6206 | ||
6207 | /* Optimize pow(x,y)*pow(x,z) as pow(x,y+z). */ | |
6208 | if (operand_equal_p (arg00, arg10, 0)) | |
6209 | { | |
6210 | tree powfn = TREE_OPERAND (TREE_OPERAND (arg0, 0), 0); | |
6211 | tree arg = fold (build (PLUS_EXPR, type, arg01, arg11)); | |
6212 | tree arglist = tree_cons (NULL_TREE, arg00, | |
6213 | build_tree_list (NULL_TREE, | |
6214 | arg)); | |
6215 | return build_function_call_expr (powfn, arglist); | |
6216 | } | |
4977bab6 | 6217 | } |
9f0a7f9d RS |
6218 | |
6219 | /* Optimize tan(x)*cos(x) as sin(x). */ | |
6220 | if (((fcode0 == BUILT_IN_TAN && fcode1 == BUILT_IN_COS) | |
6221 | || (fcode0 == BUILT_IN_TANF && fcode1 == BUILT_IN_COSF) | |
6222 | || (fcode0 == BUILT_IN_TANL && fcode1 == BUILT_IN_COSL) | |
6223 | || (fcode0 == BUILT_IN_COS && fcode1 == BUILT_IN_TAN) | |
6224 | || (fcode0 == BUILT_IN_COSF && fcode1 == BUILT_IN_TANF) | |
6225 | || (fcode0 == BUILT_IN_COSL && fcode1 == BUILT_IN_TANL)) | |
6226 | && operand_equal_p (TREE_VALUE (TREE_OPERAND (arg0, 1)), | |
6227 | TREE_VALUE (TREE_OPERAND (arg1, 1)), 0)) | |
6228 | { | |
6229 | tree sinfn; | |
6230 | ||
6231 | switch (fcode0) | |
6232 | { | |
6233 | case BUILT_IN_TAN: | |
6234 | case BUILT_IN_COS: | |
6235 | sinfn = implicit_built_in_decls[BUILT_IN_SIN]; | |
6236 | break; | |
6237 | case BUILT_IN_TANF: | |
6238 | case BUILT_IN_COSF: | |
6239 | sinfn = implicit_built_in_decls[BUILT_IN_SINF]; | |
6240 | break; | |
6241 | case BUILT_IN_TANL: | |
6242 | case BUILT_IN_COSL: | |
6243 | sinfn = implicit_built_in_decls[BUILT_IN_SINL]; | |
6244 | break; | |
6245 | default: | |
6246 | sinfn = NULL_TREE; | |
6247 | } | |
6248 | ||
6249 | if (sinfn != NULL_TREE) | |
6250 | return build_function_call_expr (sinfn, | |
6251 | TREE_OPERAND (arg0, 1)); | |
6252 | } | |
2598550f RS |
6253 | |
6254 | /* Optimize x*pow(x,c) as pow(x,c+1). */ | |
6255 | if (fcode1 == BUILT_IN_POW | |
6256 | || fcode1 == BUILT_IN_POWF | |
6257 | || fcode1 == BUILT_IN_POWL) | |
6258 | { | |
6259 | tree arg10 = TREE_VALUE (TREE_OPERAND (arg1, 1)); | |
6260 | tree arg11 = TREE_VALUE (TREE_CHAIN (TREE_OPERAND (arg1, | |
6261 | 1))); | |
6262 | if (TREE_CODE (arg11) == REAL_CST | |
6263 | && ! TREE_CONSTANT_OVERFLOW (arg11) | |
6264 | && operand_equal_p (arg0, arg10, 0)) | |
6265 | { | |
6266 | tree powfn = TREE_OPERAND (TREE_OPERAND (arg1, 0), 0); | |
6267 | REAL_VALUE_TYPE c; | |
6268 | tree arg, arglist; | |
6269 | ||
6270 | c = TREE_REAL_CST (arg11); | |
6271 | real_arithmetic (&c, PLUS_EXPR, &c, &dconst1); | |
6272 | arg = build_real (type, c); | |
6273 | arglist = build_tree_list (NULL_TREE, arg); | |
6274 | arglist = tree_cons (NULL_TREE, arg0, arglist); | |
6275 | return build_function_call_expr (powfn, arglist); | |
6276 | } | |
6277 | } | |
6278 | ||
6279 | /* Optimize pow(x,c)*x as pow(x,c+1). */ | |
6280 | if (fcode0 == BUILT_IN_POW | |
6281 | || fcode0 == BUILT_IN_POWF | |
6282 | || fcode0 == BUILT_IN_POWL) | |
6283 | { | |
6284 | tree arg00 = TREE_VALUE (TREE_OPERAND (arg0, 1)); | |
6285 | tree arg01 = TREE_VALUE (TREE_CHAIN (TREE_OPERAND (arg0, | |
6286 | 1))); | |
6287 | if (TREE_CODE (arg01) == REAL_CST | |
6288 | && ! TREE_CONSTANT_OVERFLOW (arg01) | |
6289 | && operand_equal_p (arg1, arg00, 0)) | |
6290 | { | |
6291 | tree powfn = TREE_OPERAND (TREE_OPERAND (arg0, 0), 0); | |
6292 | REAL_VALUE_TYPE c; | |
6293 | tree arg, arglist; | |
6294 | ||
6295 | c = TREE_REAL_CST (arg01); | |
6296 | real_arithmetic (&c, PLUS_EXPR, &c, &dconst1); | |
6297 | arg = build_real (type, c); | |
6298 | arglist = build_tree_list (NULL_TREE, arg); | |
6299 | arglist = tree_cons (NULL_TREE, arg1, arglist); | |
6300 | return build_function_call_expr (powfn, arglist); | |
6301 | } | |
6302 | } | |
6303 | ||
6304 | /* Optimize x*x as pow(x,2.0), which is expanded as x*x. */ | |
6305 | if (! optimize_size | |
6306 | && operand_equal_p (arg0, arg1, 0)) | |
6307 | { | |
6308 | tree powfn; | |
6309 | ||
6310 | if (type == double_type_node) | |
6311 | powfn = implicit_built_in_decls[BUILT_IN_POW]; | |
6312 | else if (type == float_type_node) | |
6313 | powfn = implicit_built_in_decls[BUILT_IN_POWF]; | |
6314 | else if (type == long_double_type_node) | |
6315 | powfn = implicit_built_in_decls[BUILT_IN_POWL]; | |
6316 | else | |
6317 | powfn = NULL_TREE; | |
6318 | ||
6319 | if (powfn) | |
6320 | { | |
6321 | tree arg = build_real (type, dconst2); | |
6322 | tree arglist = build_tree_list (NULL_TREE, arg); | |
6323 | arglist = tree_cons (NULL_TREE, arg0, arglist); | |
6324 | return build_function_call_expr (powfn, arglist); | |
6325 | } | |
6326 | } | |
4977bab6 | 6327 | } |
6d716ca8 RS |
6328 | } |
6329 | goto associate; | |
6330 | ||
6331 | case BIT_IOR_EXPR: | |
6332 | bit_ior: | |
6333 | if (integer_all_onesp (arg1)) | |
6334 | return omit_one_operand (type, arg1, arg0); | |
6335 | if (integer_zerop (arg1)) | |
6336 | return non_lvalue (convert (type, arg0)); | |
6337 | t1 = distribute_bit_expr (code, type, arg0, arg1); | |
6338 | if (t1 != NULL_TREE) | |
6339 | return t1; | |
85d2e16c | 6340 | |
ccc5fd95 JH |
6341 | /* Convert (or (not arg0) (not arg1)) to (not (and (arg0) (arg1))). |
6342 | ||
b6cc0a72 | 6343 | This results in more efficient code for machines without a NAND |
ccc5fd95 JH |
6344 | instruction. Combine will canonicalize to the first form |
6345 | which will allow use of NAND instructions provided by the | |
6346 | backend if they exist. */ | |
6347 | if (TREE_CODE (arg0) == BIT_NOT_EXPR | |
6348 | && TREE_CODE (arg1) == BIT_NOT_EXPR) | |
6349 | { | |
6350 | return fold (build1 (BIT_NOT_EXPR, type, | |
6351 | build (BIT_AND_EXPR, type, | |
6352 | TREE_OPERAND (arg0, 0), | |
6353 | TREE_OPERAND (arg1, 0)))); | |
6354 | } | |
6355 | ||
79e8185c JH |
6356 | /* See if this can be simplified into a rotate first. If that |
6357 | is unsuccessful continue in the association code. */ | |
6358 | goto bit_rotate; | |
6d716ca8 RS |
6359 | |
6360 | case BIT_XOR_EXPR: | |
6361 | if (integer_zerop (arg1)) | |
6362 | return non_lvalue (convert (type, arg0)); | |
6363 | if (integer_all_onesp (arg1)) | |
6364 | return fold (build1 (BIT_NOT_EXPR, type, arg0)); | |
79e8185c JH |
6365 | |
6366 | /* If we are XORing two BIT_AND_EXPR's, both of which are and'ing | |
6367 | with a constant, and the two constants have no bits in common, | |
6368 | we should treat this as a BIT_IOR_EXPR since this may produce more | |
6369 | simplifications. */ | |
6370 | if (TREE_CODE (arg0) == BIT_AND_EXPR | |
6371 | && TREE_CODE (arg1) == BIT_AND_EXPR | |
6372 | && TREE_CODE (TREE_OPERAND (arg0, 1)) == INTEGER_CST | |
6373 | && TREE_CODE (TREE_OPERAND (arg1, 1)) == INTEGER_CST | |
6374 | && integer_zerop (const_binop (BIT_AND_EXPR, | |
6375 | TREE_OPERAND (arg0, 1), | |
6376 | TREE_OPERAND (arg1, 1), 0))) | |
b6cc0a72 KH |
6377 | { |
6378 | code = BIT_IOR_EXPR; | |
6379 | goto bit_ior; | |
6380 | } | |
79e8185c | 6381 | |
03e0a65f | 6382 | /* See if this can be simplified into a rotate first. If that |
79e8185c | 6383 | is unsuccessful continue in the association code. */ |
03e0a65f | 6384 | goto bit_rotate; |
6d716ca8 RS |
6385 | |
6386 | case BIT_AND_EXPR: | |
6d716ca8 RS |
6387 | if (integer_all_onesp (arg1)) |
6388 | return non_lvalue (convert (type, arg0)); | |
6389 | if (integer_zerop (arg1)) | |
6390 | return omit_one_operand (type, arg1, arg0); | |
6391 | t1 = distribute_bit_expr (code, type, arg0, arg1); | |
6392 | if (t1 != NULL_TREE) | |
6393 | return t1; | |
2859471c | 6394 | /* Simplify ((int)c & 0377) into (int)c, if c is unsigned char. */ |
6d716ca8 RS |
6395 | if (TREE_CODE (arg1) == INTEGER_CST && TREE_CODE (arg0) == NOP_EXPR |
6396 | && TREE_UNSIGNED (TREE_TYPE (TREE_OPERAND (arg0, 0)))) | |
6397 | { | |
770ae6cc RK |
6398 | unsigned int prec |
6399 | = TYPE_PRECISION (TREE_TYPE (TREE_OPERAND (arg0, 0))); | |
6400 | ||
906c4e36 RK |
6401 | if (prec < BITS_PER_WORD && prec < HOST_BITS_PER_WIDE_INT |
6402 | && (~TREE_INT_CST_LOW (arg1) | |
6403 | & (((HOST_WIDE_INT) 1 << prec) - 1)) == 0) | |
6d716ca8 RS |
6404 | return build1 (NOP_EXPR, type, TREE_OPERAND (arg0, 0)); |
6405 | } | |
ccc5fd95 | 6406 | |
a36335da | 6407 | /* Convert (and (not arg0) (not arg1)) to (not (or (arg0) (arg1))). |
ccc5fd95 | 6408 | |
b6cc0a72 | 6409 | This results in more efficient code for machines without a NOR |
ccc5fd95 JH |
6410 | instruction. Combine will canonicalize to the first form |
6411 | which will allow use of NOR instructions provided by the | |
6412 | backend if they exist. */ | |
6413 | if (TREE_CODE (arg0) == BIT_NOT_EXPR | |
6414 | && TREE_CODE (arg1) == BIT_NOT_EXPR) | |
6415 | { | |
6416 | return fold (build1 (BIT_NOT_EXPR, type, | |
6417 | build (BIT_IOR_EXPR, type, | |
6418 | TREE_OPERAND (arg0, 0), | |
6419 | TREE_OPERAND (arg1, 0)))); | |
6420 | } | |
6421 | ||
6d716ca8 RS |
6422 | goto associate; |
6423 | ||
e9aaa5a5 | 6424 | case RDIV_EXPR: |
b216cd4a ZW |
6425 | /* Don't touch a floating-point divide by zero unless the mode |
6426 | of the constant can represent infinity. */ | |
6427 | if (TREE_CODE (arg1) == REAL_CST | |
6428 | && !MODE_HAS_INFINITIES (TYPE_MODE (TREE_TYPE (arg1))) | |
6429 | && real_zerop (arg1)) | |
e9aaa5a5 | 6430 | return t; |
e9aaa5a5 | 6431 | |
10414089 | 6432 | /* (-A) / (-B) -> A / B */ |
8ab49fef RS |
6433 | if (TREE_CODE (arg0) == NEGATE_EXPR && negate_expr_p (arg1)) |
6434 | return fold (build (RDIV_EXPR, type, | |
6435 | TREE_OPERAND (arg0, 0), | |
6436 | negate_expr (arg1))); | |
6437 | if (TREE_CODE (arg1) == NEGATE_EXPR && negate_expr_p (arg0)) | |
6438 | return fold (build (RDIV_EXPR, type, | |
6439 | negate_expr (arg0), | |
10414089 JL |
6440 | TREE_OPERAND (arg1, 0))); |
6441 | ||
52bfebf0 RS |
6442 | /* In IEEE floating point, x/1 is not equivalent to x for snans. */ |
6443 | if (!HONOR_SNANS (TYPE_MODE (TREE_TYPE (arg0))) | |
6444 | && real_onep (arg1)) | |
e9aaa5a5 RK |
6445 | return non_lvalue (convert (type, arg0)); |
6446 | ||
8ab49fef RS |
6447 | /* In IEEE floating point, x/-1 is not equivalent to -x for snans. */ |
6448 | if (!HONOR_SNANS (TYPE_MODE (TREE_TYPE (arg0))) | |
6449 | && real_minus_onep (arg1)) | |
6450 | return non_lvalue (convert (type, negate_expr (arg0))); | |
6451 | ||
e9aaa5a5 RK |
6452 | /* If ARG1 is a constant, we can convert this to a multiply by the |
6453 | reciprocal. This does not have the same rounding properties, | |
de6c5979 BL |
6454 | so only do this if -funsafe-math-optimizations. We can actually |
6455 | always safely do it if ARG1 is a power of two, but it's hard to | |
6456 | tell if it is or not in a portable manner. */ | |
39647dcb RK |
6457 | if (TREE_CODE (arg1) == REAL_CST) |
6458 | { | |
de6c5979 | 6459 | if (flag_unsafe_math_optimizations |
39647dcb RK |
6460 | && 0 != (tem = const_binop (code, build_real (type, dconst1), |
6461 | arg1, 0))) | |
6462 | return fold (build (MULT_EXPR, type, arg0, tem)); | |
30f7a378 | 6463 | /* Find the reciprocal if optimizing and the result is exact. */ |
e3232933 | 6464 | if (optimize) |
39647dcb RK |
6465 | { |
6466 | REAL_VALUE_TYPE r; | |
6467 | r = TREE_REAL_CST (arg1); | |
6468 | if (exact_real_inverse (TYPE_MODE(TREE_TYPE(arg0)), &r)) | |
b6cc0a72 KH |
6469 | { |
6470 | tem = build_real (type, r); | |
6471 | return fold (build (MULT_EXPR, type, arg0, tem)); | |
6472 | } | |
39647dcb RK |
6473 | } |
6474 | } | |
bc8d3f91 JH |
6475 | /* Convert A/B/C to A/(B*C). */ |
6476 | if (flag_unsafe_math_optimizations | |
6477 | && TREE_CODE (arg0) == RDIV_EXPR) | |
e3232933 RS |
6478 | return fold (build (RDIV_EXPR, type, TREE_OPERAND (arg0, 0), |
6479 | fold (build (MULT_EXPR, type, | |
6480 | TREE_OPERAND (arg0, 1), arg1)))); | |
6481 | ||
bc8d3f91 JH |
6482 | /* Convert A/(B/C) to (A/B)*C. */ |
6483 | if (flag_unsafe_math_optimizations | |
6484 | && TREE_CODE (arg1) == RDIV_EXPR) | |
e3232933 RS |
6485 | return fold (build (MULT_EXPR, type, |
6486 | fold (build (RDIV_EXPR, type, arg0, | |
6487 | TREE_OPERAND (arg1, 0))), | |
6488 | TREE_OPERAND (arg1, 1))); | |
6489 | ||
6490 | /* Convert C1/(X*C2) into (C1/C2)/X. */ | |
6491 | if (flag_unsafe_math_optimizations | |
6492 | && TREE_CODE (arg1) == MULT_EXPR | |
6493 | && TREE_CODE (arg0) == REAL_CST | |
6494 | && TREE_CODE (TREE_OPERAND (arg1, 1)) == REAL_CST) | |
bc8d3f91 | 6495 | { |
e3232933 RS |
6496 | tree tem = const_binop (RDIV_EXPR, arg0, |
6497 | TREE_OPERAND (arg1, 1), 0); | |
6498 | if (tem) | |
6499 | return fold (build (RDIV_EXPR, type, tem, | |
6500 | TREE_OPERAND (arg1, 0))); | |
bc8d3f91 | 6501 | } |
4977bab6 | 6502 | |
4977bab6 ZW |
6503 | if (flag_unsafe_math_optimizations) |
6504 | { | |
6505 | enum built_in_function fcode = builtin_mathfn_code (arg1); | |
f7657db9 | 6506 | /* Optimize x/expN(y) into x*expN(-y). */ |
4977bab6 ZW |
6507 | if (fcode == BUILT_IN_EXP |
6508 | || fcode == BUILT_IN_EXPF | |
f7657db9 KG |
6509 | || fcode == BUILT_IN_EXPL |
6510 | || fcode == BUILT_IN_EXP2 | |
6511 | || fcode == BUILT_IN_EXP2F | |
6512 | || fcode == BUILT_IN_EXP2L | |
6513 | || fcode == BUILT_IN_EXP10 | |
6514 | || fcode == BUILT_IN_EXP10F | |
6515 | || fcode == BUILT_IN_EXP10L | |
6516 | || fcode == BUILT_IN_POW10 | |
6517 | || fcode == BUILT_IN_POW10F | |
6518 | || fcode == BUILT_IN_POW10L) | |
4977bab6 ZW |
6519 | { |
6520 | tree expfn = TREE_OPERAND (TREE_OPERAND (arg1, 0), 0); | |
6521 | tree arg = build1 (NEGATE_EXPR, type, | |
6522 | TREE_VALUE (TREE_OPERAND (arg1, 1))); | |
5fce2c65 | 6523 | tree arglist = build_tree_list (NULL_TREE, fold (arg)); |
4977bab6 ZW |
6524 | arg1 = build_function_call_expr (expfn, arglist); |
6525 | return fold (build (MULT_EXPR, type, arg0, arg1)); | |
6526 | } | |
5fce2c65 RS |
6527 | |
6528 | /* Optimize x/pow(y,z) into x*pow(y,-z). */ | |
6529 | if (fcode == BUILT_IN_POW | |
6530 | || fcode == BUILT_IN_POWF | |
6531 | || fcode == BUILT_IN_POWL) | |
6532 | { | |
6533 | tree powfn = TREE_OPERAND (TREE_OPERAND (arg1, 0), 0); | |
6534 | tree arg10 = TREE_VALUE (TREE_OPERAND (arg1, 1)); | |
6535 | tree arg11 = TREE_VALUE (TREE_CHAIN (TREE_OPERAND (arg1, 1))); | |
6536 | tree neg11 = fold (build1 (NEGATE_EXPR, type, arg11)); | |
6537 | tree arglist = tree_cons(NULL_TREE, arg10, | |
6538 | build_tree_list (NULL_TREE, neg11)); | |
6539 | arg1 = build_function_call_expr (powfn, arglist); | |
6540 | return fold (build (MULT_EXPR, type, arg0, arg1)); | |
6541 | } | |
4977bab6 | 6542 | } |
9f0a7f9d RS |
6543 | |
6544 | if (flag_unsafe_math_optimizations) | |
6545 | { | |
6546 | enum built_in_function fcode0 = builtin_mathfn_code (arg0); | |
6547 | enum built_in_function fcode1 = builtin_mathfn_code (arg1); | |
6548 | ||
6549 | /* Optimize sin(x)/cos(x) as tan(x). */ | |
6550 | if (((fcode0 == BUILT_IN_SIN && fcode1 == BUILT_IN_COS) | |
6551 | || (fcode0 == BUILT_IN_SINF && fcode1 == BUILT_IN_COSF) | |
6552 | || (fcode0 == BUILT_IN_SINL && fcode1 == BUILT_IN_COSL)) | |
6553 | && operand_equal_p (TREE_VALUE (TREE_OPERAND (arg0, 1)), | |
6554 | TREE_VALUE (TREE_OPERAND (arg1, 1)), 0)) | |
6555 | { | |
6556 | tree tanfn; | |
6557 | ||
6558 | if (fcode0 == BUILT_IN_SIN) | |
6559 | tanfn = implicit_built_in_decls[BUILT_IN_TAN]; | |
6560 | else if (fcode0 == BUILT_IN_SINF) | |
6561 | tanfn = implicit_built_in_decls[BUILT_IN_TANF]; | |
6562 | else if (fcode0 == BUILT_IN_SINL) | |
6563 | tanfn = implicit_built_in_decls[BUILT_IN_TANL]; | |
6564 | else | |
6565 | tanfn = NULL_TREE; | |
6566 | ||
6567 | if (tanfn != NULL_TREE) | |
6568 | return build_function_call_expr (tanfn, | |
6569 | TREE_OPERAND (arg0, 1)); | |
6570 | } | |
6571 | ||
6572 | /* Optimize cos(x)/sin(x) as 1.0/tan(x). */ | |
6573 | if (((fcode0 == BUILT_IN_COS && fcode1 == BUILT_IN_SIN) | |
6574 | || (fcode0 == BUILT_IN_COSF && fcode1 == BUILT_IN_SINF) | |
6575 | || (fcode0 == BUILT_IN_COSL && fcode1 == BUILT_IN_SINL)) | |
6576 | && operand_equal_p (TREE_VALUE (TREE_OPERAND (arg0, 1)), | |
6577 | TREE_VALUE (TREE_OPERAND (arg1, 1)), 0)) | |
6578 | { | |
6579 | tree tanfn; | |
6580 | ||
6581 | if (fcode0 == BUILT_IN_COS) | |
6582 | tanfn = implicit_built_in_decls[BUILT_IN_TAN]; | |
6583 | else if (fcode0 == BUILT_IN_COSF) | |
6584 | tanfn = implicit_built_in_decls[BUILT_IN_TANF]; | |
6585 | else if (fcode0 == BUILT_IN_COSL) | |
6586 | tanfn = implicit_built_in_decls[BUILT_IN_TANL]; | |
6587 | else | |
6588 | tanfn = NULL_TREE; | |
6589 | ||
6590 | if (tanfn != NULL_TREE) | |
6591 | { | |
6592 | tree tmp = TREE_OPERAND (arg0, 1); | |
6593 | tmp = build_function_call_expr (tanfn, tmp); | |
6594 | return fold (build (RDIV_EXPR, type, | |
6595 | build_real (type, dconst1), | |
6596 | tmp)); | |
6597 | } | |
6598 | } | |
2598550f RS |
6599 | |
6600 | /* Optimize pow(x,c)/x as pow(x,c-1). */ | |
6601 | if (fcode0 == BUILT_IN_POW | |
6602 | || fcode0 == BUILT_IN_POWF | |
6603 | || fcode0 == BUILT_IN_POWL) | |
6604 | { | |
6605 | tree arg00 = TREE_VALUE (TREE_OPERAND (arg0, 1)); | |
6606 | tree arg01 = TREE_VALUE (TREE_CHAIN (TREE_OPERAND (arg0, 1))); | |
6607 | if (TREE_CODE (arg01) == REAL_CST | |
6608 | && ! TREE_CONSTANT_OVERFLOW (arg01) | |
6609 | && operand_equal_p (arg1, arg00, 0)) | |
6610 | { | |
6611 | tree powfn = TREE_OPERAND (TREE_OPERAND (arg0, 0), 0); | |
6612 | REAL_VALUE_TYPE c; | |
6613 | tree arg, arglist; | |
6614 | ||
6615 | c = TREE_REAL_CST (arg01); | |
6616 | real_arithmetic (&c, MINUS_EXPR, &c, &dconst1); | |
6617 | arg = build_real (type, c); | |
6618 | arglist = build_tree_list (NULL_TREE, arg); | |
6619 | arglist = tree_cons (NULL_TREE, arg1, arglist); | |
6620 | return build_function_call_expr (powfn, arglist); | |
6621 | } | |
6622 | } | |
9f0a7f9d | 6623 | } |
e9aaa5a5 RK |
6624 | goto binary; |
6625 | ||
6d716ca8 RS |
6626 | case TRUNC_DIV_EXPR: |
6627 | case ROUND_DIV_EXPR: | |
6628 | case FLOOR_DIV_EXPR: | |
6629 | case CEIL_DIV_EXPR: | |
6630 | case EXACT_DIV_EXPR: | |
6d716ca8 RS |
6631 | if (integer_onep (arg1)) |
6632 | return non_lvalue (convert (type, arg0)); | |
6633 | if (integer_zerop (arg1)) | |
6634 | return t; | |
3b998c11 | 6635 | |
39dfb55a JL |
6636 | /* If arg0 is a multiple of arg1, then rewrite to the fastest div |
6637 | operation, EXACT_DIV_EXPR. | |
6638 | ||
91585c63 TM |
6639 | Note that only CEIL_DIV_EXPR and FLOOR_DIV_EXPR are rewritten now. |
6640 | At one time others generated faster code, it's not clear if they do | |
6641 | after the last round to changes to the DIV code in expmed.c. */ | |
6642 | if ((code == CEIL_DIV_EXPR || code == FLOOR_DIV_EXPR) | |
39dfb55a JL |
6643 | && multiple_of_p (type, arg0, arg1)) |
6644 | return fold (build (EXACT_DIV_EXPR, type, arg0, arg1)); | |
6645 | ||
b6cc0a72 | 6646 | if (TREE_CODE (arg1) == INTEGER_CST |
1baa375f RK |
6647 | && 0 != (tem = extract_muldiv (TREE_OPERAND (t, 0), arg1, |
6648 | code, NULL_TREE))) | |
6649 | return convert (type, tem); | |
3b998c11 | 6650 | |
6d716ca8 RS |
6651 | goto binary; |
6652 | ||
6653 | case CEIL_MOD_EXPR: | |
6654 | case FLOOR_MOD_EXPR: | |
6655 | case ROUND_MOD_EXPR: | |
6656 | case TRUNC_MOD_EXPR: | |
6657 | if (integer_onep (arg1)) | |
6658 | return omit_one_operand (type, integer_zero_node, arg0); | |
6659 | if (integer_zerop (arg1)) | |
6660 | return t; | |
6a96fcb4 | 6661 | |
6a96fcb4 | 6662 | if (TREE_CODE (arg1) == INTEGER_CST |
1baa375f RK |
6663 | && 0 != (tem = extract_muldiv (TREE_OPERAND (t, 0), arg1, |
6664 | code, NULL_TREE))) | |
6665 | return convert (type, tem); | |
6a96fcb4 | 6666 | |
6d716ca8 RS |
6667 | goto binary; |
6668 | ||
6d716ca8 RS |
6669 | case LROTATE_EXPR: |
6670 | case RROTATE_EXPR: | |
4977bab6 ZW |
6671 | if (integer_all_onesp (arg0)) |
6672 | return omit_one_operand (type, arg0, arg1); | |
6673 | goto shift; | |
6674 | ||
6675 | case RSHIFT_EXPR: | |
6676 | /* Optimize -1 >> x for arithmetic right shifts. */ | |
6677 | if (integer_all_onesp (arg0) && ! TREE_UNSIGNED (type)) | |
6678 | return omit_one_operand (type, arg0, arg1); | |
6679 | /* ... fall through ... */ | |
6680 | ||
6681 | case LSHIFT_EXPR: | |
6682 | shift: | |
6d716ca8 RS |
6683 | if (integer_zerop (arg1)) |
6684 | return non_lvalue (convert (type, arg0)); | |
4977bab6 ZW |
6685 | if (integer_zerop (arg0)) |
6686 | return omit_one_operand (type, arg0, arg1); | |
6687 | ||
6d716ca8 RS |
6688 | /* Since negative shift count is not well-defined, |
6689 | don't try to compute it in the compiler. */ | |
4d39710e | 6690 | if (TREE_CODE (arg1) == INTEGER_CST && tree_int_cst_sgn (arg1) < 0) |
6d716ca8 | 6691 | return t; |
4d39710e RK |
6692 | /* Rewrite an LROTATE_EXPR by a constant into an |
6693 | RROTATE_EXPR by a new constant. */ | |
6694 | if (code == LROTATE_EXPR && TREE_CODE (arg1) == INTEGER_CST) | |
6695 | { | |
37af03cb RS |
6696 | tree tem = build_int_2 (GET_MODE_BITSIZE (TYPE_MODE (type)), 0); |
6697 | tem = convert (TREE_TYPE (arg1), tem); | |
6698 | tem = const_binop (MINUS_EXPR, tem, arg1, 0); | |
6699 | return fold (build (RROTATE_EXPR, type, arg0, tem)); | |
4d39710e RK |
6700 | } |
6701 | ||
6702 | /* If we have a rotate of a bit operation with the rotate count and | |
6703 | the second operand of the bit operation both constant, | |
6704 | permute the two operations. */ | |
6705 | if (code == RROTATE_EXPR && TREE_CODE (arg1) == INTEGER_CST | |
6706 | && (TREE_CODE (arg0) == BIT_AND_EXPR | |
4d39710e RK |
6707 | || TREE_CODE (arg0) == BIT_IOR_EXPR |
6708 | || TREE_CODE (arg0) == BIT_XOR_EXPR) | |
6709 | && TREE_CODE (TREE_OPERAND (arg0, 1)) == INTEGER_CST) | |
6710 | return fold (build (TREE_CODE (arg0), type, | |
6711 | fold (build (code, type, | |
6712 | TREE_OPERAND (arg0, 0), arg1)), | |
6713 | fold (build (code, type, | |
6714 | TREE_OPERAND (arg0, 1), arg1)))); | |
6715 | ||
6716 | /* Two consecutive rotates adding up to the width of the mode can | |
6717 | be ignored. */ | |
6718 | if (code == RROTATE_EXPR && TREE_CODE (arg1) == INTEGER_CST | |
6719 | && TREE_CODE (arg0) == RROTATE_EXPR | |
6720 | && TREE_CODE (TREE_OPERAND (arg0, 1)) == INTEGER_CST | |
6721 | && TREE_INT_CST_HIGH (arg1) == 0 | |
6722 | && TREE_INT_CST_HIGH (TREE_OPERAND (arg0, 1)) == 0 | |
6723 | && ((TREE_INT_CST_LOW (arg1) | |
6724 | + TREE_INT_CST_LOW (TREE_OPERAND (arg0, 1))) | |
05bccae2 | 6725 | == (unsigned int) GET_MODE_BITSIZE (TYPE_MODE (type)))) |
4d39710e RK |
6726 | return TREE_OPERAND (arg0, 0); |
6727 | ||
6d716ca8 RS |
6728 | goto binary; |
6729 | ||
6730 | case MIN_EXPR: | |
6731 | if (operand_equal_p (arg0, arg1, 0)) | |
13eb1f7f | 6732 | return omit_one_operand (type, arg0, arg1); |
7178e3af | 6733 | if (INTEGRAL_TYPE_P (type) |
6d716ca8 RS |
6734 | && operand_equal_p (arg1, TYPE_MIN_VALUE (type), 1)) |
6735 | return omit_one_operand (type, arg1, arg0); | |
6736 | goto associate; | |
6737 | ||
6738 | case MAX_EXPR: | |
6739 | if (operand_equal_p (arg0, arg1, 0)) | |
13eb1f7f | 6740 | return omit_one_operand (type, arg0, arg1); |
7178e3af | 6741 | if (INTEGRAL_TYPE_P (type) |
e1ee5cdc | 6742 | && TYPE_MAX_VALUE (type) |
6d716ca8 RS |
6743 | && operand_equal_p (arg1, TYPE_MAX_VALUE (type), 1)) |
6744 | return omit_one_operand (type, arg1, arg0); | |
6745 | goto associate; | |
6746 | ||
6747 | case TRUTH_NOT_EXPR: | |
6748 | /* Note that the operand of this must be an int | |
6749 | and its values must be 0 or 1. | |
6750 | ("true" is a fixed value perhaps depending on the language, | |
6751 | but we don't handle values other than 1 correctly yet.) */ | |
1180eb10 JM |
6752 | tem = invert_truthvalue (arg0); |
6753 | /* Avoid infinite recursion. */ | |
6754 | if (TREE_CODE (tem) == TRUTH_NOT_EXPR) | |
7960bf22 JL |
6755 | { |
6756 | tem = fold_single_bit_test (code, arg0, arg1, type); | |
6757 | if (tem) | |
6758 | return tem; | |
6759 | return t; | |
6760 | } | |
1180eb10 | 6761 | return convert (type, tem); |
6d716ca8 RS |
6762 | |
6763 | case TRUTH_ANDIF_EXPR: | |
6764 | /* Note that the operands of this must be ints | |
6765 | and their values must be 0 or 1. | |
6766 | ("true" is a fixed value perhaps depending on the language.) */ | |
6767 | /* If first arg is constant zero, return it. */ | |
772447c5 | 6768 | if (integer_zerop (arg0)) |
13eb1f7f | 6769 | return convert (type, arg0); |
6d716ca8 RS |
6770 | case TRUTH_AND_EXPR: |
6771 | /* If either arg is constant true, drop it. */ | |
6772 | if (TREE_CODE (arg0) == INTEGER_CST && ! integer_zerop (arg0)) | |
13eb1f7f | 6773 | return non_lvalue (convert (type, arg1)); |
235cfbc4 BS |
6774 | if (TREE_CODE (arg1) == INTEGER_CST && ! integer_zerop (arg1) |
6775 | /* Preserve sequence points. */ | |
6776 | && (code != TRUTH_ANDIF_EXPR || ! TREE_SIDE_EFFECTS (arg0))) | |
13eb1f7f | 6777 | return non_lvalue (convert (type, arg0)); |
772447c5 RK |
6778 | /* If second arg is constant zero, result is zero, but first arg |
6779 | must be evaluated. */ | |
6780 | if (integer_zerop (arg1)) | |
6781 | return omit_one_operand (type, arg1, arg0); | |
80906567 RK |
6782 | /* Likewise for first arg, but note that only the TRUTH_AND_EXPR |
6783 | case will be handled here. */ | |
6784 | if (integer_zerop (arg0)) | |
6785 | return omit_one_operand (type, arg0, arg1); | |
6d716ca8 RS |
6786 | |
6787 | truth_andor: | |
e9b5e15f RK |
6788 | /* We only do these simplifications if we are optimizing. */ |
6789 | if (!optimize) | |
6790 | return t; | |
6791 | ||
6792 | /* Check for things like (A || B) && (A || C). We can convert this | |
6793 | to A || (B && C). Note that either operator can be any of the four | |
6794 | truth and/or operations and the transformation will still be | |
6795 | valid. Also note that we only care about order for the | |
96f06cb6 | 6796 | ANDIF and ORIF operators. If B contains side effects, this |
30f7a378 | 6797 | might change the truth-value of A. */ |
e9b5e15f RK |
6798 | if (TREE_CODE (arg0) == TREE_CODE (arg1) |
6799 | && (TREE_CODE (arg0) == TRUTH_ANDIF_EXPR | |
6800 | || TREE_CODE (arg0) == TRUTH_ORIF_EXPR | |
6801 | || TREE_CODE (arg0) == TRUTH_AND_EXPR | |
96f06cb6 RK |
6802 | || TREE_CODE (arg0) == TRUTH_OR_EXPR) |
6803 | && ! TREE_SIDE_EFFECTS (TREE_OPERAND (arg0, 1))) | |
e9b5e15f RK |
6804 | { |
6805 | tree a00 = TREE_OPERAND (arg0, 0); | |
6806 | tree a01 = TREE_OPERAND (arg0, 1); | |
6807 | tree a10 = TREE_OPERAND (arg1, 0); | |
6808 | tree a11 = TREE_OPERAND (arg1, 1); | |
6809 | int commutative = ((TREE_CODE (arg0) == TRUTH_OR_EXPR | |
6810 | || TREE_CODE (arg0) == TRUTH_AND_EXPR) | |
6811 | && (code == TRUTH_AND_EXPR | |
6812 | || code == TRUTH_OR_EXPR)); | |
6813 | ||
6814 | if (operand_equal_p (a00, a10, 0)) | |
6815 | return fold (build (TREE_CODE (arg0), type, a00, | |
6816 | fold (build (code, type, a01, a11)))); | |
6817 | else if (commutative && operand_equal_p (a00, a11, 0)) | |
6818 | return fold (build (TREE_CODE (arg0), type, a00, | |
6819 | fold (build (code, type, a01, a10)))); | |
6820 | else if (commutative && operand_equal_p (a01, a10, 0)) | |
6821 | return fold (build (TREE_CODE (arg0), type, a01, | |
6822 | fold (build (code, type, a00, a11)))); | |
6823 | ||
6824 | /* This case if tricky because we must either have commutative | |
6825 | operators or else A10 must not have side-effects. */ | |
6826 | ||
6827 | else if ((commutative || ! TREE_SIDE_EFFECTS (a10)) | |
6828 | && operand_equal_p (a01, a11, 0)) | |
6829 | return fold (build (TREE_CODE (arg0), type, | |
6830 | fold (build (code, type, a00, a10)), | |
6831 | a01)); | |
6832 | } | |
6833 | ||
ebde8a27 RK |
6834 | /* See if we can build a range comparison. */ |
6835 | if (0 != (tem = fold_range_test (t))) | |
6836 | return tem; | |
6837 | ||
6d716ca8 RS |
6838 | /* Check for the possibility of merging component references. If our |
6839 | lhs is another similar operation, try to merge its rhs with our | |
6840 | rhs. Then try to merge our lhs and rhs. */ | |
e9b5e15f RK |
6841 | if (TREE_CODE (arg0) == code |
6842 | && 0 != (tem = fold_truthop (code, type, | |
6843 | TREE_OPERAND (arg0, 1), arg1))) | |
6844 | return fold (build (code, type, TREE_OPERAND (arg0, 0), tem)); | |
6d716ca8 | 6845 | |
e9b5e15f RK |
6846 | if ((tem = fold_truthop (code, type, arg0, arg1)) != 0) |
6847 | return tem; | |
61f275ff | 6848 | |
6d716ca8 RS |
6849 | return t; |
6850 | ||
6851 | case TRUTH_ORIF_EXPR: | |
6852 | /* Note that the operands of this must be ints | |
6853 | and their values must be 0 or true. | |
6854 | ("true" is a fixed value perhaps depending on the language.) */ | |
6855 | /* If first arg is constant true, return it. */ | |
6856 | if (TREE_CODE (arg0) == INTEGER_CST && ! integer_zerop (arg0)) | |
13eb1f7f | 6857 | return convert (type, arg0); |
6d716ca8 RS |
6858 | case TRUTH_OR_EXPR: |
6859 | /* If either arg is constant zero, drop it. */ | |
6860 | if (TREE_CODE (arg0) == INTEGER_CST && integer_zerop (arg0)) | |
13eb1f7f | 6861 | return non_lvalue (convert (type, arg1)); |
235cfbc4 BS |
6862 | if (TREE_CODE (arg1) == INTEGER_CST && integer_zerop (arg1) |
6863 | /* Preserve sequence points. */ | |
6864 | && (code != TRUTH_ORIF_EXPR || ! TREE_SIDE_EFFECTS (arg0))) | |
13eb1f7f | 6865 | return non_lvalue (convert (type, arg0)); |
772447c5 RK |
6866 | /* If second arg is constant true, result is true, but we must |
6867 | evaluate first arg. */ | |
6868 | if (TREE_CODE (arg1) == INTEGER_CST && ! integer_zerop (arg1)) | |
6869 | return omit_one_operand (type, arg1, arg0); | |
80906567 RK |
6870 | /* Likewise for first arg, but note this only occurs here for |
6871 | TRUTH_OR_EXPR. */ | |
6872 | if (TREE_CODE (arg0) == INTEGER_CST && ! integer_zerop (arg0)) | |
6873 | return omit_one_operand (type, arg0, arg1); | |
6d716ca8 RS |
6874 | goto truth_andor; |
6875 | ||
772447c5 RK |
6876 | case TRUTH_XOR_EXPR: |
6877 | /* If either arg is constant zero, drop it. */ | |
6878 | if (integer_zerop (arg0)) | |
13eb1f7f | 6879 | return non_lvalue (convert (type, arg1)); |
772447c5 | 6880 | if (integer_zerop (arg1)) |
13eb1f7f | 6881 | return non_lvalue (convert (type, arg0)); |
772447c5 RK |
6882 | /* If either arg is constant true, this is a logical inversion. */ |
6883 | if (integer_onep (arg0)) | |
13eb1f7f | 6884 | return non_lvalue (convert (type, invert_truthvalue (arg1))); |
772447c5 | 6885 | if (integer_onep (arg1)) |
13eb1f7f | 6886 | return non_lvalue (convert (type, invert_truthvalue (arg0))); |
62d8b51e | 6887 | return t; |
772447c5 | 6888 | |
6d716ca8 RS |
6889 | case EQ_EXPR: |
6890 | case NE_EXPR: | |
6891 | case LT_EXPR: | |
6892 | case GT_EXPR: | |
6893 | case LE_EXPR: | |
6894 | case GE_EXPR: | |
437f1df1 | 6895 | /* If one arg is a real or integer constant, put it last. */ |
37af03cb RS |
6896 | if (tree_swap_operands_p (arg0, arg1)) |
6897 | return fold (build (swap_tree_comparison (code), type, arg1, arg0)); | |
437f1df1 | 6898 | |
10414089 JL |
6899 | if (FLOAT_TYPE_P (TREE_TYPE (arg0))) |
6900 | { | |
77f9af81 JH |
6901 | tree targ0 = strip_float_extensions (arg0); |
6902 | tree targ1 = strip_float_extensions (arg1); | |
6903 | tree newtype = TREE_TYPE (targ0); | |
6904 | ||
6905 | if (TYPE_PRECISION (TREE_TYPE (targ1)) > TYPE_PRECISION (newtype)) | |
6906 | newtype = TREE_TYPE (targ1); | |
6907 | ||
6908 | /* Fold (double)float1 CMP (double)float2 into float1 CMP float2. */ | |
6909 | if (TYPE_PRECISION (newtype) < TYPE_PRECISION (TREE_TYPE (arg0))) | |
6910 | return fold (build (code, type, convert (newtype, targ0), | |
6911 | convert (newtype, targ1))); | |
6912 | ||
10414089 JL |
6913 | /* (-a) CMP (-b) -> b CMP a */ |
6914 | if (TREE_CODE (arg0) == NEGATE_EXPR | |
6915 | && TREE_CODE (arg1) == NEGATE_EXPR) | |
6916 | return fold (build (code, type, TREE_OPERAND (arg1, 0), | |
6917 | TREE_OPERAND (arg0, 0))); | |
9ddae796 RS |
6918 | |
6919 | if (TREE_CODE (arg1) == REAL_CST) | |
6920 | { | |
6921 | REAL_VALUE_TYPE cst; | |
6922 | cst = TREE_REAL_CST (arg1); | |
6923 | ||
6924 | /* (-a) CMP CST -> a swap(CMP) (-CST) */ | |
6925 | if (TREE_CODE (arg0) == NEGATE_EXPR) | |
6926 | return | |
6927 | fold (build (swap_tree_comparison (code), type, | |
6928 | TREE_OPERAND (arg0, 0), | |
6929 | build_real (TREE_TYPE (arg1), | |
6930 | REAL_VALUE_NEGATE (cst)))); | |
6931 | ||
6932 | /* IEEE doesn't distinguish +0 and -0 in comparisons. */ | |
6933 | /* a CMP (-0) -> a CMP 0 */ | |
6934 | if (REAL_VALUE_MINUS_ZERO (cst)) | |
6935 | return fold (build (code, type, arg0, | |
6936 | build_real (TREE_TYPE (arg1), dconst0))); | |
6937 | ||
6938 | /* x != NaN is always true, other ops are always false. */ | |
6939 | if (REAL_VALUE_ISNAN (cst) | |
6940 | && ! HONOR_SNANS (TYPE_MODE (TREE_TYPE (arg1)))) | |
6941 | { | |
6942 | t = (code == NE_EXPR) ? integer_one_node : integer_zero_node; | |
6943 | return omit_one_operand (type, convert (type, t), arg0); | |
6944 | } | |
6945 | ||
6946 | /* Fold comparisons against infinity. */ | |
6947 | if (REAL_VALUE_ISINF (cst)) | |
6948 | { | |
6949 | tem = fold_inf_compare (code, type, arg0, arg1); | |
6950 | if (tem != NULL_TREE) | |
6951 | return tem; | |
6952 | } | |
6953 | } | |
10414089 | 6954 | |
437f1df1 RS |
6955 | /* If this is a comparison of a real constant with a PLUS_EXPR |
6956 | or a MINUS_EXPR of a real constant, we can convert it into a | |
6957 | comparison with a revised real constant as long as no overflow | |
6958 | occurs when unsafe_math_optimizations are enabled. */ | |
6959 | if (flag_unsafe_math_optimizations | |
6960 | && TREE_CODE (arg1) == REAL_CST | |
6961 | && (TREE_CODE (arg0) == PLUS_EXPR | |
6962 | || TREE_CODE (arg0) == MINUS_EXPR) | |
6963 | && TREE_CODE (TREE_OPERAND (arg0, 1)) == REAL_CST | |
6964 | && 0 != (tem = const_binop (TREE_CODE (arg0) == PLUS_EXPR | |
6965 | ? MINUS_EXPR : PLUS_EXPR, | |
6966 | arg1, TREE_OPERAND (arg0, 1), 0)) | |
6967 | && ! TREE_CONSTANT_OVERFLOW (tem)) | |
6968 | return fold (build (code, type, TREE_OPERAND (arg0, 0), tem)); | |
c876997f | 6969 | |
15d4fd98 RS |
6970 | /* Likewise, we can simplify a comparison of a real constant with |
6971 | a MINUS_EXPR whose first operand is also a real constant, i.e. | |
6972 | (c1 - x) < c2 becomes x > c1-c2. */ | |
6973 | if (flag_unsafe_math_optimizations | |
6974 | && TREE_CODE (arg1) == REAL_CST | |
6975 | && TREE_CODE (arg0) == MINUS_EXPR | |
6976 | && TREE_CODE (TREE_OPERAND (arg0, 0)) == REAL_CST | |
6977 | && 0 != (tem = const_binop (MINUS_EXPR, TREE_OPERAND (arg0, 0), | |
6978 | arg1, 0)) | |
6979 | && ! TREE_CONSTANT_OVERFLOW (tem)) | |
6980 | return fold (build (swap_tree_comparison (code), type, | |
6981 | TREE_OPERAND (arg0, 1), tem)); | |
6982 | ||
c876997f RS |
6983 | /* Fold comparisons against built-in math functions. */ |
6984 | if (TREE_CODE (arg1) == REAL_CST | |
6985 | && flag_unsafe_math_optimizations | |
6986 | && ! flag_errno_math) | |
6987 | { | |
6988 | enum built_in_function fcode = builtin_mathfn_code (arg0); | |
6989 | ||
6990 | if (fcode != END_BUILTINS) | |
6991 | { | |
6992 | tem = fold_mathfn_compare (fcode, code, type, arg0, arg1); | |
6993 | if (tem != NULL_TREE) | |
6994 | return tem; | |
6995 | } | |
6996 | } | |
6d716ca8 RS |
6997 | } |
6998 | ||
6999 | /* Convert foo++ == CONST into ++foo == CONST + INCR. | |
7000 | First, see if one arg is constant; find the constant arg | |
7001 | and the other one. */ | |
7002 | { | |
4e86caed | 7003 | tree constop = 0, varop = NULL_TREE; |
cd7ece66 | 7004 | int constopnum = -1; |
6d716ca8 RS |
7005 | |
7006 | if (TREE_CONSTANT (arg1)) | |
cd7ece66 | 7007 | constopnum = 1, constop = arg1, varop = arg0; |
6d716ca8 | 7008 | if (TREE_CONSTANT (arg0)) |
cd7ece66 | 7009 | constopnum = 0, constop = arg0, varop = arg1; |
6d716ca8 RS |
7010 | |
7011 | if (constop && TREE_CODE (varop) == POSTINCREMENT_EXPR) | |
7012 | { | |
6d716ca8 RS |
7013 | /* This optimization is invalid for ordered comparisons |
7014 | if CONST+INCR overflows or if foo+incr might overflow. | |
c05a9b68 | 7015 | This optimization is invalid for floating point due to rounding. |
6d716ca8 | 7016 | For pointer types we assume overflow doesn't happen. */ |
e5e809f4 | 7017 | if (POINTER_TYPE_P (TREE_TYPE (varop)) |
7178e3af | 7018 | || (! FLOAT_TYPE_P (TREE_TYPE (varop)) |
c05a9b68 | 7019 | && (code == EQ_EXPR || code == NE_EXPR))) |
6d716ca8 | 7020 | { |
c05a9b68 RS |
7021 | tree newconst |
7022 | = fold (build (PLUS_EXPR, TREE_TYPE (varop), | |
7023 | constop, TREE_OPERAND (varop, 1))); | |
4d06bcc5 MM |
7024 | |
7025 | /* Do not overwrite the current varop to be a preincrement, | |
7026 | create a new node so that we won't confuse our caller who | |
7027 | might create trees and throw them away, reusing the | |
7028 | arguments that they passed to build. This shows up in | |
7029 | the THEN or ELSE parts of ?: being postincrements. */ | |
7030 | varop = build (PREINCREMENT_EXPR, TREE_TYPE (varop), | |
7031 | TREE_OPERAND (varop, 0), | |
7032 | TREE_OPERAND (varop, 1)); | |
cd7ece66 | 7033 | |
30eca391 RK |
7034 | /* If VAROP is a reference to a bitfield, we must mask |
7035 | the constant by the width of the field. */ | |
7036 | if (TREE_CODE (TREE_OPERAND (varop, 0)) == COMPONENT_REF | |
7037 | && DECL_BIT_FIELD(TREE_OPERAND | |
7038 | (TREE_OPERAND (varop, 0), 1))) | |
7039 | { | |
7040 | int size | |
7041 | = TREE_INT_CST_LOW (DECL_SIZE | |
7042 | (TREE_OPERAND | |
7043 | (TREE_OPERAND (varop, 0), 1))); | |
df0e526f | 7044 | tree mask, unsigned_type; |
770ae6cc | 7045 | unsigned int precision; |
df0e526f AS |
7046 | tree folded_compare; |
7047 | ||
7048 | /* First check whether the comparison would come out | |
7049 | always the same. If we don't do that we would | |
7050 | change the meaning with the masking. */ | |
7051 | if (constopnum == 0) | |
7052 | folded_compare = fold (build (code, type, constop, | |
7053 | TREE_OPERAND (varop, 0))); | |
7054 | else | |
7055 | folded_compare = fold (build (code, type, | |
7056 | TREE_OPERAND (varop, 0), | |
7057 | constop)); | |
7058 | if (integer_zerop (folded_compare) | |
7059 | || integer_onep (folded_compare)) | |
7060 | return omit_one_operand (type, folded_compare, varop); | |
7061 | ||
b0c48229 | 7062 | unsigned_type = (*lang_hooks.types.type_for_size)(size, 1); |
df0e526f AS |
7063 | precision = TYPE_PRECISION (unsigned_type); |
7064 | mask = build_int_2 (~0, ~0); | |
7065 | TREE_TYPE (mask) = unsigned_type; | |
7066 | force_fit_type (mask, 0); | |
7067 | mask = const_binop (RSHIFT_EXPR, mask, | |
7068 | size_int (precision - size), 0); | |
30eca391 RK |
7069 | newconst = fold (build (BIT_AND_EXPR, |
7070 | TREE_TYPE (varop), newconst, | |
7071 | convert (TREE_TYPE (varop), | |
df0e526f | 7072 | mask))); |
30eca391 | 7073 | } |
30eca391 | 7074 | |
4d06bcc5 MM |
7075 | t = build (code, type, |
7076 | (constopnum == 0) ? newconst : varop, | |
7077 | (constopnum == 1) ? newconst : varop); | |
c05a9b68 | 7078 | return t; |
6d716ca8 RS |
7079 | } |
7080 | } | |
7081 | else if (constop && TREE_CODE (varop) == POSTDECREMENT_EXPR) | |
7082 | { | |
e5e809f4 | 7083 | if (POINTER_TYPE_P (TREE_TYPE (varop)) |
7178e3af | 7084 | || (! FLOAT_TYPE_P (TREE_TYPE (varop)) |
c05a9b68 | 7085 | && (code == EQ_EXPR || code == NE_EXPR))) |
6d716ca8 | 7086 | { |
c05a9b68 RS |
7087 | tree newconst |
7088 | = fold (build (MINUS_EXPR, TREE_TYPE (varop), | |
7089 | constop, TREE_OPERAND (varop, 1))); | |
4d06bcc5 MM |
7090 | |
7091 | /* Do not overwrite the current varop to be a predecrement, | |
7092 | create a new node so that we won't confuse our caller who | |
7093 | might create trees and throw them away, reusing the | |
7094 | arguments that they passed to build. This shows up in | |
7095 | the THEN or ELSE parts of ?: being postdecrements. */ | |
7096 | varop = build (PREDECREMENT_EXPR, TREE_TYPE (varop), | |
7097 | TREE_OPERAND (varop, 0), | |
7098 | TREE_OPERAND (varop, 1)); | |
30eca391 RK |
7099 | |
7100 | if (TREE_CODE (TREE_OPERAND (varop, 0)) == COMPONENT_REF | |
7101 | && DECL_BIT_FIELD(TREE_OPERAND | |
7102 | (TREE_OPERAND (varop, 0), 1))) | |
7103 | { | |
7104 | int size | |
7105 | = TREE_INT_CST_LOW (DECL_SIZE | |
7106 | (TREE_OPERAND | |
7107 | (TREE_OPERAND (varop, 0), 1))); | |
df0e526f | 7108 | tree mask, unsigned_type; |
770ae6cc | 7109 | unsigned int precision; |
df0e526f AS |
7110 | tree folded_compare; |
7111 | ||
7112 | if (constopnum == 0) | |
7113 | folded_compare = fold (build (code, type, constop, | |
7114 | TREE_OPERAND (varop, 0))); | |
7115 | else | |
7116 | folded_compare = fold (build (code, type, | |
7117 | TREE_OPERAND (varop, 0), | |
7118 | constop)); | |
7119 | if (integer_zerop (folded_compare) | |
7120 | || integer_onep (folded_compare)) | |
7121 | return omit_one_operand (type, folded_compare, varop); | |
7122 | ||
b0c48229 | 7123 | unsigned_type = (*lang_hooks.types.type_for_size)(size, 1); |
df0e526f AS |
7124 | precision = TYPE_PRECISION (unsigned_type); |
7125 | mask = build_int_2 (~0, ~0); | |
7126 | TREE_TYPE (mask) = TREE_TYPE (varop); | |
7127 | force_fit_type (mask, 0); | |
7128 | mask = const_binop (RSHIFT_EXPR, mask, | |
7129 | size_int (precision - size), 0); | |
30eca391 RK |
7130 | newconst = fold (build (BIT_AND_EXPR, |
7131 | TREE_TYPE (varop), newconst, | |
7132 | convert (TREE_TYPE (varop), | |
df0e526f | 7133 | mask))); |
30eca391 | 7134 | } |
30eca391 | 7135 | |
4d06bcc5 MM |
7136 | t = build (code, type, |
7137 | (constopnum == 0) ? newconst : varop, | |
7138 | (constopnum == 1) ? newconst : varop); | |
c05a9b68 | 7139 | return t; |
6d716ca8 RS |
7140 | } |
7141 | } | |
7142 | } | |
7143 | ||
fa4a5557 RH |
7144 | /* Change X >= C to X > (C - 1) and X < C to X <= (C - 1) if C > 0. |
7145 | This transformation affects the cases which are handled in later | |
7146 | optimizations involving comparisons with non-negative constants. */ | |
7147 | if (TREE_CODE (arg1) == INTEGER_CST | |
7148 | && TREE_CODE (arg0) != INTEGER_CST | |
7149 | && tree_int_cst_sgn (arg1) > 0) | |
7150 | { | |
7151 | switch (code) | |
7152 | { | |
7153 | case GE_EXPR: | |
fa4a5557 | 7154 | arg1 = const_binop (MINUS_EXPR, arg1, integer_one_node, 0); |
37af03cb | 7155 | return fold (build (GT_EXPR, type, arg0, arg1)); |
fa4a5557 RH |
7156 | |
7157 | case LT_EXPR: | |
fa4a5557 | 7158 | arg1 = const_binop (MINUS_EXPR, arg1, integer_one_node, 0); |
37af03cb | 7159 | return fold (build (LE_EXPR, type, arg0, arg1)); |
fa4a5557 RH |
7160 | |
7161 | default: | |
7162 | break; | |
7163 | } | |
7164 | } | |
7165 | ||
033afd11 | 7166 | /* Comparisons with the highest or lowest possible integer of |
fa4a5557 | 7167 | the specified size will have known values. */ |
033afd11 RH |
7168 | { |
7169 | int width = GET_MODE_BITSIZE (TYPE_MODE (TREE_TYPE (arg1))); | |
7170 | ||
7171 | if (TREE_CODE (arg1) == INTEGER_CST | |
7172 | && ! TREE_CONSTANT_OVERFLOW (arg1) | |
7173 | && width <= HOST_BITS_PER_WIDE_INT | |
7174 | && (INTEGRAL_TYPE_P (TREE_TYPE (arg1)) | |
7175 | || POINTER_TYPE_P (TREE_TYPE (arg1)))) | |
7176 | { | |
fa4a5557 RH |
7177 | unsigned HOST_WIDE_INT signed_max; |
7178 | unsigned HOST_WIDE_INT max, min; | |
7179 | ||
7180 | signed_max = ((unsigned HOST_WIDE_INT) 1 << (width - 1)) - 1; | |
7181 | ||
7182 | if (TREE_UNSIGNED (TREE_TYPE (arg1))) | |
7183 | { | |
7184 | max = ((unsigned HOST_WIDE_INT) 2 << (width - 1)) - 1; | |
7185 | min = 0; | |
7186 | } | |
7187 | else | |
7188 | { | |
7189 | max = signed_max; | |
7190 | min = ((unsigned HOST_WIDE_INT) -1 << (width - 1)); | |
7191 | } | |
7192 | ||
033afd11 | 7193 | if (TREE_INT_CST_HIGH (arg1) == 0 |
fa4a5557 RH |
7194 | && TREE_INT_CST_LOW (arg1) == max) |
7195 | switch (code) | |
033afd11 RH |
7196 | { |
7197 | case GT_EXPR: | |
7198 | return omit_one_operand (type, | |
7199 | convert (type, integer_zero_node), | |
7200 | arg0); | |
7201 | case GE_EXPR: | |
37af03cb RS |
7202 | return fold (build (EQ_EXPR, type, arg0, arg1)); |
7203 | ||
033afd11 RH |
7204 | case LE_EXPR: |
7205 | return omit_one_operand (type, | |
7206 | convert (type, integer_one_node), | |
7207 | arg0); | |
7208 | case LT_EXPR: | |
37af03cb | 7209 | return fold (build (NE_EXPR, type, arg0, arg1)); |
033afd11 | 7210 | |
fa4a5557 | 7211 | /* The GE_EXPR and LT_EXPR cases above are not normally |
37af03cb | 7212 | reached because of previous transformations. */ |
fa4a5557 | 7213 | |
033afd11 RH |
7214 | default: |
7215 | break; | |
7216 | } | |
fa4a5557 RH |
7217 | else if (TREE_INT_CST_HIGH (arg1) == 0 |
7218 | && TREE_INT_CST_LOW (arg1) == max - 1) | |
7219 | switch (code) | |
7220 | { | |
7221 | case GT_EXPR: | |
fa4a5557 | 7222 | arg1 = const_binop (PLUS_EXPR, arg1, integer_one_node, 0); |
37af03cb | 7223 | return fold (build (EQ_EXPR, type, arg0, arg1)); |
fa4a5557 | 7224 | case LE_EXPR: |
fa4a5557 | 7225 | arg1 = const_binop (PLUS_EXPR, arg1, integer_one_node, 0); |
37af03cb | 7226 | return fold (build (NE_EXPR, type, arg0, arg1)); |
fa4a5557 RH |
7227 | default: |
7228 | break; | |
7229 | } | |
7230 | else if (TREE_INT_CST_HIGH (arg1) == (min ? -1 : 0) | |
7231 | && TREE_INT_CST_LOW (arg1) == min) | |
7232 | switch (code) | |
033afd11 RH |
7233 | { |
7234 | case LT_EXPR: | |
7235 | return omit_one_operand (type, | |
7236 | convert (type, integer_zero_node), | |
7237 | arg0); | |
7238 | case LE_EXPR: | |
37af03cb | 7239 | return fold (build (EQ_EXPR, type, arg0, arg1)); |
033afd11 RH |
7240 | |
7241 | case GE_EXPR: | |
7242 | return omit_one_operand (type, | |
7243 | convert (type, integer_one_node), | |
7244 | arg0); | |
7245 | case GT_EXPR: | |
37af03cb | 7246 | return fold (build (NE_EXPR, type, arg0, arg1)); |
033afd11 RH |
7247 | |
7248 | default: | |
7249 | break; | |
7250 | } | |
fa4a5557 RH |
7251 | else if (TREE_INT_CST_HIGH (arg1) == (min ? -1 : 0) |
7252 | && TREE_INT_CST_LOW (arg1) == min + 1) | |
7253 | switch (code) | |
7254 | { | |
7255 | case GE_EXPR: | |
fa4a5557 | 7256 | arg1 = const_binop (MINUS_EXPR, arg1, integer_one_node, 0); |
37af03cb | 7257 | return fold (build (NE_EXPR, type, arg0, arg1)); |
fa4a5557 | 7258 | case LT_EXPR: |
fa4a5557 | 7259 | arg1 = const_binop (MINUS_EXPR, arg1, integer_one_node, 0); |
37af03cb | 7260 | return fold (build (EQ_EXPR, type, arg0, arg1)); |
fa4a5557 RH |
7261 | default: |
7262 | break; | |
7263 | } | |
033afd11 RH |
7264 | |
7265 | else if (TREE_INT_CST_HIGH (arg1) == 0 | |
fa4a5557 | 7266 | && TREE_INT_CST_LOW (arg1) == signed_max |
033afd11 RH |
7267 | && TREE_UNSIGNED (TREE_TYPE (arg1)) |
7268 | /* signed_type does not work on pointer types. */ | |
7269 | && INTEGRAL_TYPE_P (TREE_TYPE (arg1))) | |
7270 | { | |
fa4a5557 RH |
7271 | /* The following case also applies to X < signed_max+1 |
7272 | and X >= signed_max+1 because previous transformations. */ | |
7273 | if (code == LE_EXPR || code == GT_EXPR) | |
033afd11 RH |
7274 | { |
7275 | tree st0, st1; | |
7276 | st0 = (*lang_hooks.types.signed_type) (TREE_TYPE (arg0)); | |
7277 | st1 = (*lang_hooks.types.signed_type) (TREE_TYPE (arg1)); | |
7278 | return fold | |
fa4a5557 | 7279 | (build (code == LE_EXPR ? GE_EXPR: LT_EXPR, |
033afd11 RH |
7280 | type, convert (st0, arg0), |
7281 | convert (st1, integer_zero_node))); | |
7282 | } | |
7283 | } | |
033afd11 RH |
7284 | } |
7285 | } | |
7286 | ||
14a774a9 RK |
7287 | /* If this is an EQ or NE comparison of a constant with a PLUS_EXPR or |
7288 | a MINUS_EXPR of a constant, we can convert it into a comparison with | |
7289 | a revised constant as long as no overflow occurs. */ | |
7290 | if ((code == EQ_EXPR || code == NE_EXPR) | |
7291 | && TREE_CODE (arg1) == INTEGER_CST | |
7292 | && (TREE_CODE (arg0) == PLUS_EXPR | |
7293 | || TREE_CODE (arg0) == MINUS_EXPR) | |
7294 | && TREE_CODE (TREE_OPERAND (arg0, 1)) == INTEGER_CST | |
7295 | && 0 != (tem = const_binop (TREE_CODE (arg0) == PLUS_EXPR | |
7296 | ? MINUS_EXPR : PLUS_EXPR, | |
7297 | arg1, TREE_OPERAND (arg0, 1), 0)) | |
7298 | && ! TREE_CONSTANT_OVERFLOW (tem)) | |
7299 | return fold (build (code, type, TREE_OPERAND (arg0, 0), tem)); | |
7300 | ||
7301 | /* Similarly for a NEGATE_EXPR. */ | |
7302 | else if ((code == EQ_EXPR || code == NE_EXPR) | |
7303 | && TREE_CODE (arg0) == NEGATE_EXPR | |
7304 | && TREE_CODE (arg1) == INTEGER_CST | |
1baa375f | 7305 | && 0 != (tem = negate_expr (arg1)) |
14a774a9 RK |
7306 | && TREE_CODE (tem) == INTEGER_CST |
7307 | && ! TREE_CONSTANT_OVERFLOW (tem)) | |
7308 | return fold (build (code, type, TREE_OPERAND (arg0, 0), tem)); | |
7309 | ||
7310 | /* If we have X - Y == 0, we can convert that to X == Y and similarly | |
7311 | for !=. Don't do this for ordered comparisons due to overflow. */ | |
7312 | else if ((code == NE_EXPR || code == EQ_EXPR) | |
7313 | && integer_zerop (arg1) && TREE_CODE (arg0) == MINUS_EXPR) | |
7314 | return fold (build (code, type, | |
7315 | TREE_OPERAND (arg0, 0), TREE_OPERAND (arg0, 1))); | |
7316 | ||
7317 | /* If we are widening one operand of an integer comparison, | |
7318 | see if the other operand is similarly being widened. Perhaps we | |
7319 | can do the comparison in the narrower type. */ | |
7320 | else if (TREE_CODE (TREE_TYPE (arg0)) == INTEGER_TYPE | |
7321 | && TREE_CODE (arg0) == NOP_EXPR | |
7322 | && (tem = get_unwidened (arg0, NULL_TREE)) != arg0 | |
7323 | && (t1 = get_unwidened (arg1, TREE_TYPE (tem))) != 0 | |
7324 | && (TREE_TYPE (t1) == TREE_TYPE (tem) | |
7325 | || (TREE_CODE (t1) == INTEGER_CST | |
7326 | && int_fits_type_p (t1, TREE_TYPE (tem))))) | |
7327 | return fold (build (code, type, tem, convert (TREE_TYPE (tem), t1))); | |
b6cc0a72 | 7328 | |
14a774a9 RK |
7329 | /* If this is comparing a constant with a MIN_EXPR or a MAX_EXPR of a |
7330 | constant, we can simplify it. */ | |
7331 | else if (TREE_CODE (arg1) == INTEGER_CST | |
7332 | && (TREE_CODE (arg0) == MIN_EXPR | |
7333 | || TREE_CODE (arg0) == MAX_EXPR) | |
7334 | && TREE_CODE (TREE_OPERAND (arg0, 1)) == INTEGER_CST) | |
7335 | return optimize_minmax_comparison (t); | |
7336 | ||
7337 | /* If we are comparing an ABS_EXPR with a constant, we can | |
7338 | convert all the cases into explicit comparisons, but they may | |
7339 | well not be faster than doing the ABS and one comparison. | |
7340 | But ABS (X) <= C is a range comparison, which becomes a subtraction | |
7341 | and a comparison, and is probably faster. */ | |
7342 | else if (code == LE_EXPR && TREE_CODE (arg1) == INTEGER_CST | |
7343 | && TREE_CODE (arg0) == ABS_EXPR | |
1baa375f RK |
7344 | && ! TREE_SIDE_EFFECTS (arg0) |
7345 | && (0 != (tem = negate_expr (arg1))) | |
7346 | && TREE_CODE (tem) == INTEGER_CST | |
7347 | && ! TREE_CONSTANT_OVERFLOW (tem)) | |
7348 | return fold (build (TRUTH_ANDIF_EXPR, type, | |
7349 | build (GE_EXPR, type, TREE_OPERAND (arg0, 0), tem), | |
7350 | build (LE_EXPR, type, | |
7351 | TREE_OPERAND (arg0, 0), arg1))); | |
b6cc0a72 | 7352 | |
6d716ca8 RS |
7353 | /* If this is an EQ or NE comparison with zero and ARG0 is |
7354 | (1 << foo) & bar, convert it to (bar >> foo) & 1. Both require | |
7355 | two operations, but the latter can be done in one less insn | |
e9a25f70 | 7356 | on machines that have only two-operand insns or on which a |
6d716ca8 RS |
7357 | constant cannot be the first operand. */ |
7358 | if (integer_zerop (arg1) && (code == EQ_EXPR || code == NE_EXPR) | |
7359 | && TREE_CODE (arg0) == BIT_AND_EXPR) | |
7360 | { | |
7361 | if (TREE_CODE (TREE_OPERAND (arg0, 0)) == LSHIFT_EXPR | |
7362 | && integer_onep (TREE_OPERAND (TREE_OPERAND (arg0, 0), 0))) | |
7363 | return | |
7364 | fold (build (code, type, | |
7365 | build (BIT_AND_EXPR, TREE_TYPE (arg0), | |
7366 | build (RSHIFT_EXPR, | |
7367 | TREE_TYPE (TREE_OPERAND (arg0, 0)), | |
7368 | TREE_OPERAND (arg0, 1), | |
7369 | TREE_OPERAND (TREE_OPERAND (arg0, 0), 1)), | |
7370 | convert (TREE_TYPE (arg0), | |
7371 | integer_one_node)), | |
7372 | arg1)); | |
7373 | else if (TREE_CODE (TREE_OPERAND (arg0, 1)) == LSHIFT_EXPR | |
7374 | && integer_onep (TREE_OPERAND (TREE_OPERAND (arg0, 1), 0))) | |
7375 | return | |
7376 | fold (build (code, type, | |
7377 | build (BIT_AND_EXPR, TREE_TYPE (arg0), | |
7378 | build (RSHIFT_EXPR, | |
7379 | TREE_TYPE (TREE_OPERAND (arg0, 1)), | |
7380 | TREE_OPERAND (arg0, 0), | |
7381 | TREE_OPERAND (TREE_OPERAND (arg0, 1), 1)), | |
7382 | convert (TREE_TYPE (arg0), | |
7383 | integer_one_node)), | |
7384 | arg1)); | |
7385 | } | |
7386 | ||
05a0d5ea | 7387 | /* If this is an NE or EQ comparison of zero against the result of a |
79bf94d3 RK |
7388 | signed MOD operation whose second operand is a power of 2, make |
7389 | the MOD operation unsigned since it is simpler and equivalent. */ | |
05a0d5ea RK |
7390 | if ((code == NE_EXPR || code == EQ_EXPR) |
7391 | && integer_zerop (arg1) | |
7392 | && ! TREE_UNSIGNED (TREE_TYPE (arg0)) | |
7393 | && (TREE_CODE (arg0) == TRUNC_MOD_EXPR | |
7394 | || TREE_CODE (arg0) == CEIL_MOD_EXPR | |
7395 | || TREE_CODE (arg0) == FLOOR_MOD_EXPR | |
79bf94d3 RK |
7396 | || TREE_CODE (arg0) == ROUND_MOD_EXPR) |
7397 | && integer_pow2p (TREE_OPERAND (arg0, 1))) | |
05a0d5ea | 7398 | { |
ceef8ce4 | 7399 | tree newtype = (*lang_hooks.types.unsigned_type) (TREE_TYPE (arg0)); |
05a0d5ea RK |
7400 | tree newmod = build (TREE_CODE (arg0), newtype, |
7401 | convert (newtype, TREE_OPERAND (arg0, 0)), | |
7402 | convert (newtype, TREE_OPERAND (arg0, 1))); | |
7403 | ||
7404 | return build (code, type, newmod, convert (newtype, arg1)); | |
7405 | } | |
7406 | ||
6d716ca8 RS |
7407 | /* If this is an NE comparison of zero with an AND of one, remove the |
7408 | comparison since the AND will give the correct value. */ | |
7409 | if (code == NE_EXPR && integer_zerop (arg1) | |
7410 | && TREE_CODE (arg0) == BIT_AND_EXPR | |
7411 | && integer_onep (TREE_OPERAND (arg0, 1))) | |
7412 | return convert (type, arg0); | |
7413 | ||
7414 | /* If we have (A & C) == C where C is a power of 2, convert this into | |
7415 | (A & C) != 0. Similarly for NE_EXPR. */ | |
7416 | if ((code == EQ_EXPR || code == NE_EXPR) | |
7417 | && TREE_CODE (arg0) == BIT_AND_EXPR | |
7418 | && integer_pow2p (TREE_OPERAND (arg0, 1)) | |
7419 | && operand_equal_p (TREE_OPERAND (arg0, 1), arg1, 0)) | |
1f77b5da RS |
7420 | return fold (build (code == EQ_EXPR ? NE_EXPR : EQ_EXPR, type, |
7421 | arg0, integer_zero_node)); | |
7422 | ||
7960bf22 JL |
7423 | /* If we have (A & C) != 0 or (A & C) == 0 and C is a power of |
7424 | 2, then fold the expression into shifts and logical operations. */ | |
7425 | tem = fold_single_bit_test (code, arg0, arg1, type); | |
7426 | if (tem) | |
7427 | return tem; | |
6d716ca8 | 7428 | |
b7de5864 ZD |
7429 | /* If we have (A & C) == D where D & ~C != 0, convert this into 0. |
7430 | Similarly for NE_EXPR. */ | |
7431 | if ((code == EQ_EXPR || code == NE_EXPR) | |
7432 | && TREE_CODE (arg0) == BIT_AND_EXPR | |
7433 | && TREE_CODE (arg1) == INTEGER_CST | |
7434 | && TREE_CODE (TREE_OPERAND (arg0, 1)) == INTEGER_CST) | |
7435 | { | |
31934da7 JZ |
7436 | tree dandnotc |
7437 | = fold (build (BIT_AND_EXPR, TREE_TYPE (arg0), | |
7438 | arg1, build1 (BIT_NOT_EXPR, | |
7439 | TREE_TYPE (TREE_OPERAND (arg0, 1)), | |
7440 | TREE_OPERAND (arg0, 1)))); | |
b7de5864 | 7441 | tree rslt = code == EQ_EXPR ? integer_zero_node : integer_one_node; |
ed6f90f7 | 7442 | if (integer_nonzerop (dandnotc)) |
b7de5864 ZD |
7443 | return omit_one_operand (type, rslt, arg0); |
7444 | } | |
7445 | ||
7446 | /* If we have (A | C) == D where C & ~D != 0, convert this into 0. | |
7447 | Similarly for NE_EXPR. */ | |
7448 | if ((code == EQ_EXPR || code == NE_EXPR) | |
7449 | && TREE_CODE (arg0) == BIT_IOR_EXPR | |
7450 | && TREE_CODE (arg1) == INTEGER_CST | |
7451 | && TREE_CODE (TREE_OPERAND (arg0, 1)) == INTEGER_CST) | |
7452 | { | |
31934da7 JZ |
7453 | tree candnotd |
7454 | = fold (build (BIT_AND_EXPR, TREE_TYPE (arg0), | |
7455 | TREE_OPERAND (arg0, 1), | |
7456 | build1 (BIT_NOT_EXPR, TREE_TYPE (arg1), arg1))); | |
b7de5864 | 7457 | tree rslt = code == EQ_EXPR ? integer_zero_node : integer_one_node; |
ed6f90f7 | 7458 | if (integer_nonzerop (candnotd)) |
b7de5864 ZD |
7459 | return omit_one_operand (type, rslt, arg0); |
7460 | } | |
7461 | ||
e92d3048 | 7462 | /* If X is unsigned, convert X < (1 << Y) into X >> Y == 0 |
34b1b41f | 7463 | and similarly for >= into !=. */ |
e92d3048 RK |
7464 | if ((code == LT_EXPR || code == GE_EXPR) |
7465 | && TREE_UNSIGNED (TREE_TYPE (arg0)) | |
7466 | && TREE_CODE (arg1) == LSHIFT_EXPR | |
7467 | && integer_onep (TREE_OPERAND (arg1, 0))) | |
b6cc0a72 | 7468 | return build (code == LT_EXPR ? EQ_EXPR : NE_EXPR, type, |
e92d3048 RK |
7469 | build (RSHIFT_EXPR, TREE_TYPE (arg0), arg0, |
7470 | TREE_OPERAND (arg1, 1)), | |
7471 | convert (TREE_TYPE (arg0), integer_zero_node)); | |
7472 | ||
7473 | else if ((code == LT_EXPR || code == GE_EXPR) | |
7474 | && TREE_UNSIGNED (TREE_TYPE (arg0)) | |
7475 | && (TREE_CODE (arg1) == NOP_EXPR | |
7476 | || TREE_CODE (arg1) == CONVERT_EXPR) | |
7477 | && TREE_CODE (TREE_OPERAND (arg1, 0)) == LSHIFT_EXPR | |
7478 | && integer_onep (TREE_OPERAND (TREE_OPERAND (arg1, 0), 0))) | |
7479 | return | |
7480 | build (code == LT_EXPR ? EQ_EXPR : NE_EXPR, type, | |
7481 | convert (TREE_TYPE (arg0), | |
7482 | build (RSHIFT_EXPR, TREE_TYPE (arg0), arg0, | |
7483 | TREE_OPERAND (TREE_OPERAND (arg1, 0), 1))), | |
7484 | convert (TREE_TYPE (arg0), integer_zero_node)); | |
7485 | ||
c05a9b68 RS |
7486 | /* Simplify comparison of something with itself. (For IEEE |
7487 | floating-point, we can only do some of these simplifications.) */ | |
7488 | if (operand_equal_p (arg0, arg1, 0)) | |
6d716ca8 RS |
7489 | { |
7490 | switch (code) | |
7491 | { | |
7492 | case EQ_EXPR: | |
37af03cb RS |
7493 | if (! FLOAT_TYPE_P (TREE_TYPE (arg0)) |
7494 | || ! HONOR_NANS (TYPE_MODE (TREE_TYPE (arg0)))) | |
7495 | return constant_boolean_node (1, type); | |
7496 | break; | |
7497 | ||
6d716ca8 RS |
7498 | case GE_EXPR: |
7499 | case LE_EXPR: | |
8936c82f RS |
7500 | if (! FLOAT_TYPE_P (TREE_TYPE (arg0)) |
7501 | || ! HONOR_NANS (TYPE_MODE (TREE_TYPE (arg0)))) | |
f628873f | 7502 | return constant_boolean_node (1, type); |
37af03cb | 7503 | return fold (build (EQ_EXPR, type, arg0, arg1)); |
c05a9b68 | 7504 | |
6d716ca8 | 7505 | case NE_EXPR: |
8936c82f RS |
7506 | /* For NE, we can only do this simplification if integer |
7507 | or we don't honor IEEE floating point NaNs. */ | |
7508 | if (FLOAT_TYPE_P (TREE_TYPE (arg0)) | |
7509 | && HONOR_NANS (TYPE_MODE (TREE_TYPE (arg0)))) | |
c05a9b68 | 7510 | break; |
0f41302f | 7511 | /* ... fall through ... */ |
6d716ca8 RS |
7512 | case GT_EXPR: |
7513 | case LT_EXPR: | |
f628873f | 7514 | return constant_boolean_node (0, type); |
e9a25f70 JL |
7515 | default: |
7516 | abort (); | |
6d716ca8 RS |
7517 | } |
7518 | } | |
7519 | ||
c05a9b68 RS |
7520 | /* If we are comparing an expression that just has comparisons |
7521 | of two integer values, arithmetic expressions of those comparisons, | |
7522 | and constants, we can simplify it. There are only three cases | |
7523 | to check: the two values can either be equal, the first can be | |
7524 | greater, or the second can be greater. Fold the expression for | |
7525 | those three values. Since each value must be 0 or 1, we have | |
7526 | eight possibilities, each of which corresponds to the constant 0 | |
7527 | or 1 or one of the six possible comparisons. | |
7528 | ||
7529 | This handles common cases like (a > b) == 0 but also handles | |
7530 | expressions like ((x > y) - (y > x)) > 0, which supposedly | |
7531 | occur in macroized code. */ | |
7532 | ||
7533 | if (TREE_CODE (arg1) == INTEGER_CST && TREE_CODE (arg0) != INTEGER_CST) | |
7534 | { | |
7535 | tree cval1 = 0, cval2 = 0; | |
35e66bd1 | 7536 | int save_p = 0; |
c05a9b68 | 7537 | |
35e66bd1 | 7538 | if (twoval_comparison_p (arg0, &cval1, &cval2, &save_p) |
c05a9b68 RS |
7539 | /* Don't handle degenerate cases here; they should already |
7540 | have been handled anyway. */ | |
7541 | && cval1 != 0 && cval2 != 0 | |
7542 | && ! (TREE_CONSTANT (cval1) && TREE_CONSTANT (cval2)) | |
7543 | && TREE_TYPE (cval1) == TREE_TYPE (cval2) | |
7178e3af | 7544 | && INTEGRAL_TYPE_P (TREE_TYPE (cval1)) |
e1ee5cdc RH |
7545 | && TYPE_MAX_VALUE (TREE_TYPE (cval1)) |
7546 | && TYPE_MAX_VALUE (TREE_TYPE (cval2)) | |
c05a9b68 RS |
7547 | && ! operand_equal_p (TYPE_MIN_VALUE (TREE_TYPE (cval1)), |
7548 | TYPE_MAX_VALUE (TREE_TYPE (cval2)), 0)) | |
7549 | { | |
7550 | tree maxval = TYPE_MAX_VALUE (TREE_TYPE (cval1)); | |
7551 | tree minval = TYPE_MIN_VALUE (TREE_TYPE (cval1)); | |
7552 | ||
7553 | /* We can't just pass T to eval_subst in case cval1 or cval2 | |
7554 | was the same as ARG1. */ | |
7555 | ||
7556 | tree high_result | |
7557 | = fold (build (code, type, | |
7558 | eval_subst (arg0, cval1, maxval, cval2, minval), | |
7559 | arg1)); | |
7560 | tree equal_result | |
7561 | = fold (build (code, type, | |
7562 | eval_subst (arg0, cval1, maxval, cval2, maxval), | |
7563 | arg1)); | |
7564 | tree low_result | |
7565 | = fold (build (code, type, | |
7566 | eval_subst (arg0, cval1, minval, cval2, maxval), | |
7567 | arg1)); | |
7568 | ||
7569 | /* All three of these results should be 0 or 1. Confirm they | |
7570 | are. Then use those values to select the proper code | |
7571 | to use. */ | |
7572 | ||
7573 | if ((integer_zerop (high_result) | |
7574 | || integer_onep (high_result)) | |
7575 | && (integer_zerop (equal_result) | |
7576 | || integer_onep (equal_result)) | |
7577 | && (integer_zerop (low_result) | |
7578 | || integer_onep (low_result))) | |
7579 | { | |
7580 | /* Make a 3-bit mask with the high-order bit being the | |
7581 | value for `>', the next for '=', and the low for '<'. */ | |
7582 | switch ((integer_onep (high_result) * 4) | |
7583 | + (integer_onep (equal_result) * 2) | |
7584 | + integer_onep (low_result)) | |
7585 | { | |
7586 | case 0: | |
7587 | /* Always false. */ | |
13837058 | 7588 | return omit_one_operand (type, integer_zero_node, arg0); |
c05a9b68 RS |
7589 | case 1: |
7590 | code = LT_EXPR; | |
7591 | break; | |
7592 | case 2: | |
7593 | code = EQ_EXPR; | |
7594 | break; | |
7595 | case 3: | |
7596 | code = LE_EXPR; | |
7597 | break; | |
7598 | case 4: | |
7599 | code = GT_EXPR; | |
7600 | break; | |
7601 | case 5: | |
7602 | code = NE_EXPR; | |
7603 | break; | |
7604 | case 6: | |
7605 | code = GE_EXPR; | |
7606 | break; | |
7607 | case 7: | |
7608 | /* Always true. */ | |
13837058 | 7609 | return omit_one_operand (type, integer_one_node, arg0); |
c05a9b68 RS |
7610 | } |
7611 | ||
35e66bd1 RK |
7612 | t = build (code, type, cval1, cval2); |
7613 | if (save_p) | |
7614 | return save_expr (t); | |
7615 | else | |
7616 | return fold (t); | |
c05a9b68 RS |
7617 | } |
7618 | } | |
7619 | } | |
7620 | ||
7621 | /* If this is a comparison of a field, we may be able to simplify it. */ | |
57ce46bb TT |
7622 | if (((TREE_CODE (arg0) == COMPONENT_REF |
7623 | && (*lang_hooks.can_use_bit_fields_p) ()) | |
9c922ec7 MM |
7624 | || TREE_CODE (arg0) == BIT_FIELD_REF) |
7625 | && (code == EQ_EXPR || code == NE_EXPR) | |
7626 | /* Handle the constant case even without -O | |
7627 | to make sure the warnings are given. */ | |
7628 | && (optimize || TREE_CODE (arg1) == INTEGER_CST)) | |
7629 | { | |
7630 | t1 = optimize_bit_field_compare (code, type, arg0, arg1); | |
7631 | return t1 ? t1 : t; | |
7632 | } | |
c05a9b68 | 7633 | |
9ec36da5 JL |
7634 | /* If this is a comparison of complex values and either or both sides |
7635 | are a COMPLEX_EXPR or COMPLEX_CST, it is best to split up the | |
7636 | comparisons and join them with a TRUTH_ANDIF_EXPR or TRUTH_ORIF_EXPR. | |
7637 | This may prevent needless evaluations. */ | |
95aa28ae RK |
7638 | if ((code == EQ_EXPR || code == NE_EXPR) |
7639 | && TREE_CODE (TREE_TYPE (arg0)) == COMPLEX_TYPE | |
7640 | && (TREE_CODE (arg0) == COMPLEX_EXPR | |
9ec36da5 JL |
7641 | || TREE_CODE (arg1) == COMPLEX_EXPR |
7642 | || TREE_CODE (arg0) == COMPLEX_CST | |
7643 | || TREE_CODE (arg1) == COMPLEX_CST)) | |
95aa28ae RK |
7644 | { |
7645 | tree subtype = TREE_TYPE (TREE_TYPE (arg0)); | |
f0b8d9aa AS |
7646 | tree real0, imag0, real1, imag1; |
7647 | ||
7648 | arg0 = save_expr (arg0); | |
7649 | arg1 = save_expr (arg1); | |
7650 | real0 = fold (build1 (REALPART_EXPR, subtype, arg0)); | |
7651 | imag0 = fold (build1 (IMAGPART_EXPR, subtype, arg0)); | |
7652 | real1 = fold (build1 (REALPART_EXPR, subtype, arg1)); | |
7653 | imag1 = fold (build1 (IMAGPART_EXPR, subtype, arg1)); | |
95aa28ae RK |
7654 | |
7655 | return fold (build ((code == EQ_EXPR ? TRUTH_ANDIF_EXPR | |
7656 | : TRUTH_ORIF_EXPR), | |
7657 | type, | |
7658 | fold (build (code, type, real0, real1)), | |
7659 | fold (build (code, type, imag0, imag1)))); | |
7660 | } | |
7661 | ||
d59b3b67 | 7662 | /* Optimize comparisons of strlen vs zero to a compare of the |
dd3f0101 | 7663 | first character of the string vs zero. To wit, |
fa8db1f7 | 7664 | strlen(ptr) == 0 => *ptr == 0 |
d59b3b67 RS |
7665 | strlen(ptr) != 0 => *ptr != 0 |
7666 | Other cases should reduce to one of these two (or a constant) | |
7667 | due to the return value of strlen being unsigned. */ | |
7668 | if ((code == EQ_EXPR || code == NE_EXPR) | |
7669 | && integer_zerop (arg1) | |
2f503025 | 7670 | && TREE_CODE (arg0) == CALL_EXPR) |
d59b3b67 | 7671 | { |
2f503025 | 7672 | tree fndecl = get_callee_fndecl (arg0); |
d59b3b67 RS |
7673 | tree arglist; |
7674 | ||
2f503025 | 7675 | if (fndecl |
d59b3b67 RS |
7676 | && DECL_BUILT_IN (fndecl) |
7677 | && DECL_BUILT_IN_CLASS (fndecl) != BUILT_IN_MD | |
7678 | && DECL_FUNCTION_CODE (fndecl) == BUILT_IN_STRLEN | |
7679 | && (arglist = TREE_OPERAND (arg0, 1)) | |
7680 | && TREE_CODE (TREE_TYPE (TREE_VALUE (arglist))) == POINTER_TYPE | |
7681 | && ! TREE_CHAIN (arglist)) | |
7682 | return fold (build (code, type, | |
7683 | build1 (INDIRECT_REF, char_type_node, | |
7684 | TREE_VALUE(arglist)), | |
7685 | integer_zero_node)); | |
7686 | } | |
7687 | ||
c05a9b68 RS |
7688 | /* From here on, the only cases we handle are when the result is |
7689 | known to be a constant. | |
7690 | ||
7691 | To compute GT, swap the arguments and do LT. | |
6d716ca8 RS |
7692 | To compute GE, do LT and invert the result. |
7693 | To compute LE, swap the arguments, do LT and invert the result. | |
c05a9b68 RS |
7694 | To compute NE, do EQ and invert the result. |
7695 | ||
7696 | Therefore, the code below must handle only EQ and LT. */ | |
7697 | ||
6d716ca8 RS |
7698 | if (code == LE_EXPR || code == GT_EXPR) |
7699 | { | |
c05a9b68 RS |
7700 | tem = arg0, arg0 = arg1, arg1 = tem; |
7701 | code = swap_tree_comparison (code); | |
7702 | } | |
7703 | ||
7704 | /* Note that it is safe to invert for real values here because we | |
7705 | will check below in the one case that it matters. */ | |
7706 | ||
14a774a9 | 7707 | t1 = NULL_TREE; |
c05a9b68 RS |
7708 | invert = 0; |
7709 | if (code == NE_EXPR || code == GE_EXPR) | |
7710 | { | |
7711 | invert = 1; | |
7712 | code = invert_tree_comparison (code); | |
6d716ca8 RS |
7713 | } |
7714 | ||
7715 | /* Compute a result for LT or EQ if args permit; | |
7716 | otherwise return T. */ | |
c05a9b68 | 7717 | if (TREE_CODE (arg0) == INTEGER_CST && TREE_CODE (arg1) == INTEGER_CST) |
6d716ca8 | 7718 | { |
c05a9b68 | 7719 | if (code == EQ_EXPR) |
05bccae2 | 7720 | t1 = build_int_2 (tree_int_cst_equal (arg0, arg1), 0); |
6d716ca8 | 7721 | else |
c05a9b68 RS |
7722 | t1 = build_int_2 ((TREE_UNSIGNED (TREE_TYPE (arg0)) |
7723 | ? INT_CST_LT_UNSIGNED (arg0, arg1) | |
7724 | : INT_CST_LT (arg0, arg1)), | |
7725 | 0); | |
6d716ca8 | 7726 | } |
c05a9b68 | 7727 | |
e80c9ccb | 7728 | #if 0 /* This is no longer useful, but breaks some real code. */ |
6d716ca8 RS |
7729 | /* Assume a nonexplicit constant cannot equal an explicit one, |
7730 | since such code would be undefined anyway. | |
7731 | Exception: on sysvr4, using #pragma weak, | |
7732 | a label can come out as 0. */ | |
7733 | else if (TREE_CODE (arg1) == INTEGER_CST | |
7734 | && !integer_zerop (arg1) | |
7735 | && TREE_CONSTANT (arg0) | |
7736 | && TREE_CODE (arg0) == ADDR_EXPR | |
c05a9b68 RS |
7737 | && code == EQ_EXPR) |
7738 | t1 = build_int_2 (0, 0); | |
e80c9ccb | 7739 | #endif |
6d716ca8 | 7740 | /* Two real constants can be compared explicitly. */ |
c05a9b68 | 7741 | else if (TREE_CODE (arg0) == REAL_CST && TREE_CODE (arg1) == REAL_CST) |
6d716ca8 | 7742 | { |
c05a9b68 RS |
7743 | /* If either operand is a NaN, the result is false with two |
7744 | exceptions: First, an NE_EXPR is true on NaNs, but that case | |
7745 | is already handled correctly since we will be inverting the | |
7746 | result for NE_EXPR. Second, if we had inverted a LE_EXPR | |
7747 | or a GE_EXPR into a LT_EXPR, we must return true so that it | |
7748 | will be inverted into false. */ | |
7749 | ||
7750 | if (REAL_VALUE_ISNAN (TREE_REAL_CST (arg0)) | |
7751 | || REAL_VALUE_ISNAN (TREE_REAL_CST (arg1))) | |
7752 | t1 = build_int_2 (invert && code == LT_EXPR, 0); | |
7753 | ||
7754 | else if (code == EQ_EXPR) | |
7755 | t1 = build_int_2 (REAL_VALUES_EQUAL (TREE_REAL_CST (arg0), | |
7756 | TREE_REAL_CST (arg1)), | |
7757 | 0); | |
6d716ca8 | 7758 | else |
c05a9b68 RS |
7759 | t1 = build_int_2 (REAL_VALUES_LESS (TREE_REAL_CST (arg0), |
7760 | TREE_REAL_CST (arg1)), | |
7761 | 0); | |
6d716ca8 RS |
7762 | } |
7763 | ||
c05a9b68 RS |
7764 | if (t1 == NULL_TREE) |
7765 | return t; | |
7766 | ||
7767 | if (invert) | |
7768 | TREE_INT_CST_LOW (t1) ^= 1; | |
7769 | ||
7770 | TREE_TYPE (t1) = type; | |
c651e1e0 | 7771 | if (TREE_CODE (type) == BOOLEAN_TYPE) |
78ef5b89 | 7772 | return (*lang_hooks.truthvalue_conversion) (t1); |
c05a9b68 | 7773 | return t1; |
6d716ca8 RS |
7774 | |
7775 | case COND_EXPR: | |
a5e9b124 JW |
7776 | /* Pedantic ANSI C says that a conditional expression is never an lvalue, |
7777 | so all simple results must be passed through pedantic_non_lvalue. */ | |
6d716ca8 | 7778 | if (TREE_CODE (arg0) == INTEGER_CST) |
a5e9b124 JW |
7779 | return pedantic_non_lvalue |
7780 | (TREE_OPERAND (t, (integer_zerop (arg0) ? 2 : 1))); | |
6d716ca8 | 7781 | else if (operand_equal_p (arg1, TREE_OPERAND (expr, 2), 0)) |
4ab3cb65 | 7782 | return pedantic_omit_one_operand (type, arg1, arg0); |
6d716ca8 | 7783 | |
c05a9b68 RS |
7784 | /* If we have A op B ? A : C, we may be able to convert this to a |
7785 | simpler expression, depending on the operation and the values | |
71925bc0 RS |
7786 | of B and C. Signed zeros prevent all of these transformations, |
7787 | for reasons given above each one. */ | |
6d716ca8 | 7788 | |
c05a9b68 RS |
7789 | if (TREE_CODE_CLASS (TREE_CODE (arg0)) == '<' |
7790 | && operand_equal_for_comparison_p (TREE_OPERAND (arg0, 0), | |
71925bc0 RS |
7791 | arg1, TREE_OPERAND (arg0, 1)) |
7792 | && !HONOR_SIGNED_ZEROS (TYPE_MODE (TREE_TYPE (arg1)))) | |
6d716ca8 | 7793 | { |
c05a9b68 RS |
7794 | tree arg2 = TREE_OPERAND (t, 2); |
7795 | enum tree_code comp_code = TREE_CODE (arg0); | |
7796 | ||
3a96b5eb RK |
7797 | STRIP_NOPS (arg2); |
7798 | ||
71925bc0 RS |
7799 | /* If we have A op 0 ? A : -A, consider applying the following |
7800 | transformations: | |
7801 | ||
7802 | A == 0? A : -A same as -A | |
7803 | A != 0? A : -A same as A | |
7804 | A >= 0? A : -A same as abs (A) | |
7805 | A > 0? A : -A same as abs (A) | |
7806 | A <= 0? A : -A same as -abs (A) | |
7807 | A < 0? A : -A same as -abs (A) | |
7808 | ||
7809 | None of these transformations work for modes with signed | |
7810 | zeros. If A is +/-0, the first two transformations will | |
7811 | change the sign of the result (from +0 to -0, or vice | |
7812 | versa). The last four will fix the sign of the result, | |
7813 | even though the original expressions could be positive or | |
7814 | negative, depending on the sign of A. | |
7815 | ||
7816 | Note that all these transformations are correct if A is | |
7817 | NaN, since the two alternatives (A and -A) are also NaNs. */ | |
68c6b3a9 DE |
7818 | if ((FLOAT_TYPE_P (TREE_TYPE (TREE_OPERAND (arg0, 1))) |
7819 | ? real_zerop (TREE_OPERAND (arg0, 1)) | |
7820 | : integer_zerop (TREE_OPERAND (arg0, 1))) | |
c05a9b68 RS |
7821 | && TREE_CODE (arg2) == NEGATE_EXPR |
7822 | && operand_equal_p (TREE_OPERAND (arg2, 0), arg1, 0)) | |
7823 | switch (comp_code) | |
7824 | { | |
7825 | case EQ_EXPR: | |
c9869b75 | 7826 | return |
b8fbe62c RK |
7827 | pedantic_non_lvalue |
7828 | (convert (type, | |
7829 | negate_expr | |
7830 | (convert (TREE_TYPE (TREE_OPERAND (t, 1)), | |
7831 | arg1)))); | |
c05a9b68 | 7832 | case NE_EXPR: |
a5e9b124 | 7833 | return pedantic_non_lvalue (convert (type, arg1)); |
c05a9b68 RS |
7834 | case GE_EXPR: |
7835 | case GT_EXPR: | |
899f1ed6 | 7836 | if (TREE_UNSIGNED (TREE_TYPE (arg1))) |
ceef8ce4 NB |
7837 | arg1 = convert ((*lang_hooks.types.signed_type) |
7838 | (TREE_TYPE (arg1)), arg1); | |
a5e9b124 | 7839 | return pedantic_non_lvalue |
21403f14 RK |
7840 | (convert (type, fold (build1 (ABS_EXPR, |
7841 | TREE_TYPE (arg1), arg1)))); | |
c05a9b68 RS |
7842 | case LE_EXPR: |
7843 | case LT_EXPR: | |
899f1ed6 | 7844 | if (TREE_UNSIGNED (TREE_TYPE (arg1))) |
ceef8ce4 NB |
7845 | arg1 = convert ((lang_hooks.types.signed_type) |
7846 | (TREE_TYPE (arg1)), arg1); | |
a5e9b124 | 7847 | return pedantic_non_lvalue |
1baa375f RK |
7848 | (negate_expr (convert (type, |
7849 | fold (build1 (ABS_EXPR, | |
7850 | TREE_TYPE (arg1), | |
7851 | arg1))))); | |
e9a25f70 JL |
7852 | default: |
7853 | abort (); | |
c05a9b68 | 7854 | } |
6d716ca8 | 7855 | |
71925bc0 RS |
7856 | /* A != 0 ? A : 0 is simply A, unless A is -0. Likewise |
7857 | A == 0 ? A : 0 is always 0 unless A is -0. Note that | |
7858 | both transformations are correct when A is NaN: A != 0 | |
7859 | is then true, and A == 0 is false. */ | |
6d716ca8 | 7860 | |
29ebe69a | 7861 | if (integer_zerop (TREE_OPERAND (arg0, 1)) && integer_zerop (arg2)) |
c05a9b68 RS |
7862 | { |
7863 | if (comp_code == NE_EXPR) | |
a5e9b124 | 7864 | return pedantic_non_lvalue (convert (type, arg1)); |
c05a9b68 | 7865 | else if (comp_code == EQ_EXPR) |
a5e9b124 | 7866 | return pedantic_non_lvalue (convert (type, integer_zero_node)); |
c05a9b68 RS |
7867 | } |
7868 | ||
71925bc0 RS |
7869 | /* Try some transformations of A op B ? A : B. |
7870 | ||
7871 | A == B? A : B same as B | |
7872 | A != B? A : B same as A | |
7873 | A >= B? A : B same as max (A, B) | |
7874 | A > B? A : B same as max (B, A) | |
7875 | A <= B? A : B same as min (A, B) | |
7876 | A < B? A : B same as min (B, A) | |
7877 | ||
7878 | As above, these transformations don't work in the presence | |
7879 | of signed zeros. For example, if A and B are zeros of | |
7880 | opposite sign, the first two transformations will change | |
7881 | the sign of the result. In the last four, the original | |
7882 | expressions give different results for (A=+0, B=-0) and | |
7883 | (A=-0, B=+0), but the transformed expressions do not. | |
7884 | ||
7885 | The first two transformations are correct if either A or B | |
7886 | is a NaN. In the first transformation, the condition will | |
7887 | be false, and B will indeed be chosen. In the case of the | |
7888 | second transformation, the condition A != B will be true, | |
7889 | and A will be chosen. | |
7890 | ||
7891 | The conversions to max() and min() are not correct if B is | |
7892 | a number and A is not. The conditions in the original | |
7893 | expressions will be false, so all four give B. The min() | |
7894 | and max() versions would give a NaN instead. */ | |
c05a9b68 RS |
7895 | if (operand_equal_for_comparison_p (TREE_OPERAND (arg0, 1), |
7896 | arg2, TREE_OPERAND (arg0, 0))) | |
3a96b5eb RK |
7897 | { |
7898 | tree comp_op0 = TREE_OPERAND (arg0, 0); | |
7899 | tree comp_op1 = TREE_OPERAND (arg0, 1); | |
7900 | tree comp_type = TREE_TYPE (comp_op0); | |
7901 | ||
a7833bec JM |
7902 | /* Avoid adding NOP_EXPRs in case this is an lvalue. */ |
7903 | if (TYPE_MAIN_VARIANT (comp_type) == TYPE_MAIN_VARIANT (type)) | |
4e8dca1c JM |
7904 | { |
7905 | comp_type = type; | |
7906 | comp_op0 = arg1; | |
7907 | comp_op1 = arg2; | |
7908 | } | |
a7833bec | 7909 | |
3a96b5eb RK |
7910 | switch (comp_code) |
7911 | { | |
7912 | case EQ_EXPR: | |
7913 | return pedantic_non_lvalue (convert (type, arg2)); | |
7914 | case NE_EXPR: | |
7915 | return pedantic_non_lvalue (convert (type, arg1)); | |
7916 | case LE_EXPR: | |
7917 | case LT_EXPR: | |
e9a25f70 JL |
7918 | /* In C++ a ?: expression can be an lvalue, so put the |
7919 | operand which will be used if they are equal first | |
b6cc0a72 | 7920 | so that we can convert this back to the |
e9a25f70 | 7921 | corresponding COND_EXPR. */ |
71925bc0 RS |
7922 | if (!HONOR_NANS (TYPE_MODE (TREE_TYPE (arg1)))) |
7923 | return pedantic_non_lvalue | |
7924 | (convert (type, fold (build (MIN_EXPR, comp_type, | |
7925 | (comp_code == LE_EXPR | |
7926 | ? comp_op0 : comp_op1), | |
7927 | (comp_code == LE_EXPR | |
7928 | ? comp_op1 : comp_op0))))); | |
88a5cdb8 | 7929 | break; |
3a96b5eb RK |
7930 | case GE_EXPR: |
7931 | case GT_EXPR: | |
71925bc0 RS |
7932 | if (!HONOR_NANS (TYPE_MODE (TREE_TYPE (arg1)))) |
7933 | return pedantic_non_lvalue | |
7934 | (convert (type, fold (build (MAX_EXPR, comp_type, | |
7935 | (comp_code == GE_EXPR | |
7936 | ? comp_op0 : comp_op1), | |
7937 | (comp_code == GE_EXPR | |
7938 | ? comp_op1 : comp_op0))))); | |
88a5cdb8 | 7939 | break; |
e9a25f70 JL |
7940 | default: |
7941 | abort (); | |
3a96b5eb RK |
7942 | } |
7943 | } | |
c05a9b68 RS |
7944 | |
7945 | /* If this is A op C1 ? A : C2 with C1 and C2 constant integers, | |
7946 | we might still be able to simplify this. For example, | |
7947 | if C1 is one less or one more than C2, this might have started | |
53d2fb4f | 7948 | out as a MIN or MAX and been transformed by this function. |
7178e3af | 7949 | Only good for INTEGER_TYPEs, because we need TYPE_MAX_VALUE. */ |
c05a9b68 | 7950 | |
7178e3af | 7951 | if (INTEGRAL_TYPE_P (type) |
53d2fb4f | 7952 | && TREE_CODE (TREE_OPERAND (arg0, 1)) == INTEGER_CST |
c05a9b68 RS |
7953 | && TREE_CODE (arg2) == INTEGER_CST) |
7954 | switch (comp_code) | |
7955 | { | |
7956 | case EQ_EXPR: | |
7957 | /* We can replace A with C1 in this case. */ | |
cd7ece66 | 7958 | arg1 = convert (type, TREE_OPERAND (arg0, 1)); |
37af03cb RS |
7959 | return fold (build (code, type, TREE_OPERAND (t, 0), arg1, |
7960 | TREE_OPERAND (t, 2))); | |
c05a9b68 RS |
7961 | |
7962 | case LT_EXPR: | |
7963 | /* If C1 is C2 + 1, this is min(A, C2). */ | |
7964 | if (! operand_equal_p (arg2, TYPE_MAX_VALUE (type), 1) | |
7965 | && operand_equal_p (TREE_OPERAND (arg0, 1), | |
7966 | const_binop (PLUS_EXPR, arg2, | |
91d33e36 | 7967 | integer_one_node, 0), 1)) |
a5e9b124 JW |
7968 | return pedantic_non_lvalue |
7969 | (fold (build (MIN_EXPR, type, arg1, arg2))); | |
c05a9b68 RS |
7970 | break; |
7971 | ||
7972 | case LE_EXPR: | |
7973 | /* If C1 is C2 - 1, this is min(A, C2). */ | |
7974 | if (! operand_equal_p (arg2, TYPE_MIN_VALUE (type), 1) | |
7975 | && operand_equal_p (TREE_OPERAND (arg0, 1), | |
7976 | const_binop (MINUS_EXPR, arg2, | |
91d33e36 | 7977 | integer_one_node, 0), 1)) |
a5e9b124 JW |
7978 | return pedantic_non_lvalue |
7979 | (fold (build (MIN_EXPR, type, arg1, arg2))); | |
c05a9b68 RS |
7980 | break; |
7981 | ||
7982 | case GT_EXPR: | |
7983 | /* If C1 is C2 - 1, this is max(A, C2). */ | |
7984 | if (! operand_equal_p (arg2, TYPE_MIN_VALUE (type), 1) | |
7985 | && operand_equal_p (TREE_OPERAND (arg0, 1), | |
7986 | const_binop (MINUS_EXPR, arg2, | |
91d33e36 | 7987 | integer_one_node, 0), 1)) |
a5e9b124 JW |
7988 | return pedantic_non_lvalue |
7989 | (fold (build (MAX_EXPR, type, arg1, arg2))); | |
c05a9b68 RS |
7990 | break; |
7991 | ||
7992 | case GE_EXPR: | |
7993 | /* If C1 is C2 + 1, this is max(A, C2). */ | |
7994 | if (! operand_equal_p (arg2, TYPE_MAX_VALUE (type), 1) | |
7995 | && operand_equal_p (TREE_OPERAND (arg0, 1), | |
7996 | const_binop (PLUS_EXPR, arg2, | |
91d33e36 | 7997 | integer_one_node, 0), 1)) |
a5e9b124 JW |
7998 | return pedantic_non_lvalue |
7999 | (fold (build (MAX_EXPR, type, arg1, arg2))); | |
c05a9b68 | 8000 | break; |
e9a25f70 JL |
8001 | case NE_EXPR: |
8002 | break; | |
8003 | default: | |
8004 | abort (); | |
c05a9b68 | 8005 | } |
6d716ca8 RS |
8006 | } |
8007 | ||
e1f56f62 RK |
8008 | /* If the second operand is simpler than the third, swap them |
8009 | since that produces better jump optimization results. */ | |
37af03cb | 8010 | if (tree_swap_operands_p (TREE_OPERAND (t, 1), TREE_OPERAND (t, 2))) |
e1f56f62 RK |
8011 | { |
8012 | /* See if this can be inverted. If it can't, possibly because | |
8013 | it was a floating-point inequality comparison, don't do | |
8014 | anything. */ | |
8015 | tem = invert_truthvalue (arg0); | |
8016 | ||
8017 | if (TREE_CODE (tem) != TRUTH_NOT_EXPR) | |
37af03cb RS |
8018 | return fold (build (code, type, tem, |
8019 | TREE_OPERAND (t, 2), TREE_OPERAND (t, 1))); | |
e1f56f62 RK |
8020 | } |
8021 | ||
c05a9b68 RS |
8022 | /* Convert A ? 1 : 0 to simply A. */ |
8023 | if (integer_onep (TREE_OPERAND (t, 1)) | |
8024 | && integer_zerop (TREE_OPERAND (t, 2)) | |
8025 | /* If we try to convert TREE_OPERAND (t, 0) to our type, the | |
b6cc0a72 | 8026 | call to fold will try to move the conversion inside |
c05a9b68 RS |
8027 | a COND, which will recurse. In that case, the COND_EXPR |
8028 | is probably the best choice, so leave it alone. */ | |
8029 | && type == TREE_TYPE (arg0)) | |
a5e9b124 | 8030 | return pedantic_non_lvalue (arg0); |
6d716ca8 | 8031 | |
6bfa5aac RS |
8032 | /* Convert A ? 0 : 1 to !A. This prefers the use of NOT_EXPR |
8033 | over COND_EXPR in cases such as floating point comparisons. */ | |
8034 | if (integer_zerop (TREE_OPERAND (t, 1)) | |
8035 | && integer_onep (TREE_OPERAND (t, 2)) | |
8036 | && truth_value_p (TREE_CODE (arg0))) | |
8037 | return pedantic_non_lvalue (convert (type, | |
8038 | invert_truthvalue (arg0))); | |
8039 | ||
c05a9b68 RS |
8040 | /* Look for expressions of the form A & 2 ? 2 : 0. The result of this |
8041 | operation is simply A & 2. */ | |
6d716ca8 RS |
8042 | |
8043 | if (integer_zerop (TREE_OPERAND (t, 2)) | |
8044 | && TREE_CODE (arg0) == NE_EXPR | |
8045 | && integer_zerop (TREE_OPERAND (arg0, 1)) | |
c05a9b68 RS |
8046 | && integer_pow2p (arg1) |
8047 | && TREE_CODE (TREE_OPERAND (arg0, 0)) == BIT_AND_EXPR | |
8048 | && operand_equal_p (TREE_OPERAND (TREE_OPERAND (arg0, 0), 1), | |
8049 | arg1, 1)) | |
a5e9b124 | 8050 | return pedantic_non_lvalue (convert (type, TREE_OPERAND (arg0, 0))); |
6d716ca8 | 8051 | |
6bfa5aac RS |
8052 | /* Convert A ? B : 0 into A && B if A and B are truth values. */ |
8053 | if (integer_zerop (TREE_OPERAND (t, 2)) | |
8054 | && truth_value_p (TREE_CODE (arg0)) | |
8055 | && truth_value_p (TREE_CODE (arg1))) | |
8056 | return pedantic_non_lvalue (fold (build (TRUTH_ANDIF_EXPR, type, | |
8057 | arg0, arg1))); | |
8058 | ||
8059 | /* Convert A ? B : 1 into !A || B if A and B are truth values. */ | |
8060 | if (integer_onep (TREE_OPERAND (t, 2)) | |
8061 | && truth_value_p (TREE_CODE (arg0)) | |
8062 | && truth_value_p (TREE_CODE (arg1))) | |
8063 | { | |
8064 | /* Only perform transformation if ARG0 is easily inverted. */ | |
8065 | tem = invert_truthvalue (arg0); | |
8066 | if (TREE_CODE (tem) != TRUTH_NOT_EXPR) | |
8067 | return pedantic_non_lvalue (fold (build (TRUTH_ORIF_EXPR, type, | |
8068 | tem, arg1))); | |
8069 | } | |
8070 | ||
6d716ca8 RS |
8071 | return t; |
8072 | ||
8073 | case COMPOUND_EXPR: | |
b7647895 JW |
8074 | /* When pedantic, a compound expression can be neither an lvalue |
8075 | nor an integer constant expression. */ | |
8076 | if (TREE_SIDE_EFFECTS (arg0) || pedantic) | |
d023bff9 RS |
8077 | return t; |
8078 | /* Don't let (0, 0) be null pointer constant. */ | |
8079 | if (integer_zerop (arg1)) | |
13eb1f7f RK |
8080 | return build1 (NOP_EXPR, type, arg1); |
8081 | return convert (type, arg1); | |
6d716ca8 | 8082 | |
1cc1b11a RS |
8083 | case COMPLEX_EXPR: |
8084 | if (wins) | |
214d5b84 | 8085 | return build_complex (type, arg0, arg1); |
1cc1b11a RS |
8086 | return t; |
8087 | ||
8088 | case REALPART_EXPR: | |
a333b79f | 8089 | if (TREE_CODE (TREE_TYPE (arg0)) != COMPLEX_TYPE) |
1cc1b11a RS |
8090 | return t; |
8091 | else if (TREE_CODE (arg0) == COMPLEX_EXPR) | |
8092 | return omit_one_operand (type, TREE_OPERAND (arg0, 0), | |
8093 | TREE_OPERAND (arg0, 1)); | |
8094 | else if (TREE_CODE (arg0) == COMPLEX_CST) | |
8095 | return TREE_REALPART (arg0); | |
8096 | else if (TREE_CODE (arg0) == PLUS_EXPR || TREE_CODE (arg0) == MINUS_EXPR) | |
a3279355 RK |
8097 | return fold (build (TREE_CODE (arg0), type, |
8098 | fold (build1 (REALPART_EXPR, type, | |
8099 | TREE_OPERAND (arg0, 0))), | |
8100 | fold (build1 (REALPART_EXPR, | |
8101 | type, TREE_OPERAND (arg0, 1))))); | |
1cc1b11a RS |
8102 | return t; |
8103 | ||
8104 | case IMAGPART_EXPR: | |
a333b79f | 8105 | if (TREE_CODE (TREE_TYPE (arg0)) != COMPLEX_TYPE) |
1cc1b11a RS |
8106 | return convert (type, integer_zero_node); |
8107 | else if (TREE_CODE (arg0) == COMPLEX_EXPR) | |
8108 | return omit_one_operand (type, TREE_OPERAND (arg0, 1), | |
8109 | TREE_OPERAND (arg0, 0)); | |
8110 | else if (TREE_CODE (arg0) == COMPLEX_CST) | |
8111 | return TREE_IMAGPART (arg0); | |
8112 | else if (TREE_CODE (arg0) == PLUS_EXPR || TREE_CODE (arg0) == MINUS_EXPR) | |
a3279355 RK |
8113 | return fold (build (TREE_CODE (arg0), type, |
8114 | fold (build1 (IMAGPART_EXPR, type, | |
8115 | TREE_OPERAND (arg0, 0))), | |
8116 | fold (build1 (IMAGPART_EXPR, type, | |
8117 | TREE_OPERAND (arg0, 1))))); | |
1cc1b11a RS |
8118 | return t; |
8119 | ||
56c98e5b JM |
8120 | /* Pull arithmetic ops out of the CLEANUP_POINT_EXPR where |
8121 | appropriate. */ | |
8122 | case CLEANUP_POINT_EXPR: | |
b7f6588d | 8123 | if (! has_cleanups (arg0)) |
3ffcb234 | 8124 | return TREE_OPERAND (t, 0); |
56c98e5b JM |
8125 | |
8126 | { | |
8127 | enum tree_code code0 = TREE_CODE (arg0); | |
8128 | int kind0 = TREE_CODE_CLASS (code0); | |
8129 | tree arg00 = TREE_OPERAND (arg0, 0); | |
8130 | tree arg01; | |
8131 | ||
0982a4b8 | 8132 | if (kind0 == '1' || code0 == TRUTH_NOT_EXPR) |
b6cc0a72 | 8133 | return fold (build1 (code0, type, |
56c98e5b JM |
8134 | fold (build1 (CLEANUP_POINT_EXPR, |
8135 | TREE_TYPE (arg00), arg00)))); | |
0982a4b8 JM |
8136 | |
8137 | if (kind0 == '<' || kind0 == '2' | |
8138 | || code0 == TRUTH_ANDIF_EXPR || code0 == TRUTH_ORIF_EXPR | |
8139 | || code0 == TRUTH_AND_EXPR || code0 == TRUTH_OR_EXPR | |
8140 | || code0 == TRUTH_XOR_EXPR) | |
8141 | { | |
8142 | arg01 = TREE_OPERAND (arg0, 1); | |
8143 | ||
b7f6588d JM |
8144 | if (TREE_CONSTANT (arg00) |
8145 | || ((code0 == TRUTH_ANDIF_EXPR || code0 == TRUTH_ORIF_EXPR) | |
8146 | && ! has_cleanups (arg00))) | |
0982a4b8 JM |
8147 | return fold (build (code0, type, arg00, |
8148 | fold (build1 (CLEANUP_POINT_EXPR, | |
8149 | TREE_TYPE (arg01), arg01)))); | |
8150 | ||
b7f6588d | 8151 | if (TREE_CONSTANT (arg01)) |
0982a4b8 JM |
8152 | return fold (build (code0, type, |
8153 | fold (build1 (CLEANUP_POINT_EXPR, | |
8154 | TREE_TYPE (arg00), arg00)), | |
8155 | arg01)); | |
8156 | } | |
56c98e5b JM |
8157 | |
8158 | return t; | |
8159 | } | |
8160 | ||
b0b3afb2 BS |
8161 | case CALL_EXPR: |
8162 | /* Check for a built-in function. */ | |
8163 | if (TREE_CODE (TREE_OPERAND (expr, 0)) == ADDR_EXPR | |
8164 | && (TREE_CODE (TREE_OPERAND (TREE_OPERAND (expr, 0), 0)) | |
8165 | == FUNCTION_DECL) | |
8166 | && DECL_BUILT_IN (TREE_OPERAND (TREE_OPERAND (expr, 0), 0))) | |
8167 | { | |
8168 | tree tmp = fold_builtin (expr); | |
8169 | if (tmp) | |
8170 | return tmp; | |
8171 | } | |
8172 | return t; | |
8173 | ||
6d716ca8 RS |
8174 | default: |
8175 | return t; | |
8176 | } /* switch (code) */ | |
8177 | } | |
39dfb55a | 8178 | |
5dfa45d0 JJ |
8179 | #ifdef ENABLE_FOLD_CHECKING |
8180 | #undef fold | |
8181 | ||
8182 | static void fold_checksum_tree (tree, struct md5_ctx *, htab_t); | |
8183 | static void fold_check_failed (tree, tree); | |
8184 | void print_fold_checksum (tree); | |
8185 | ||
8186 | /* When --enable-checking=fold, compute a digest of expr before | |
8187 | and after actual fold call to see if fold did not accidentally | |
8188 | change original expr. */ | |
8189 | ||
8190 | tree | |
8191 | fold (tree expr) | |
8192 | { | |
8193 | tree ret; | |
8194 | struct md5_ctx ctx; | |
8195 | unsigned char checksum_before[16], checksum_after[16]; | |
8196 | htab_t ht; | |
8197 | ||
8198 | ht = htab_create (32, htab_hash_pointer, htab_eq_pointer, NULL); | |
8199 | md5_init_ctx (&ctx); | |
8200 | fold_checksum_tree (expr, &ctx, ht); | |
8201 | md5_finish_ctx (&ctx, checksum_before); | |
8202 | htab_empty (ht); | |
8203 | ||
8204 | ret = fold_1 (expr); | |
8205 | ||
8206 | md5_init_ctx (&ctx); | |
8207 | fold_checksum_tree (expr, &ctx, ht); | |
8208 | md5_finish_ctx (&ctx, checksum_after); | |
8209 | htab_delete (ht); | |
8210 | ||
8211 | if (memcmp (checksum_before, checksum_after, 16)) | |
8212 | fold_check_failed (expr, ret); | |
8213 | ||
8214 | return ret; | |
8215 | } | |
8216 | ||
8217 | void | |
8218 | print_fold_checksum (tree expr) | |
8219 | { | |
8220 | struct md5_ctx ctx; | |
8221 | unsigned char checksum[16], cnt; | |
8222 | htab_t ht; | |
8223 | ||
8224 | ht = htab_create (32, htab_hash_pointer, htab_eq_pointer, NULL); | |
8225 | md5_init_ctx (&ctx); | |
8226 | fold_checksum_tree (expr, &ctx, ht); | |
8227 | md5_finish_ctx (&ctx, checksum); | |
8228 | htab_delete (ht); | |
8229 | for (cnt = 0; cnt < 16; ++cnt) | |
8230 | fprintf (stderr, "%02x", checksum[cnt]); | |
8231 | putc ('\n', stderr); | |
8232 | } | |
8233 | ||
8234 | static void | |
8235 | fold_check_failed (tree expr ATTRIBUTE_UNUSED, tree ret ATTRIBUTE_UNUSED) | |
8236 | { | |
8237 | internal_error ("fold check: original tree changed by fold"); | |
8238 | } | |
8239 | ||
8240 | static void | |
8241 | fold_checksum_tree (tree expr, struct md5_ctx *ctx, htab_t ht) | |
8242 | { | |
8243 | void **slot; | |
8244 | enum tree_code code; | |
8245 | char buf[sizeof (struct tree_decl)]; | |
8246 | int i, len; | |
8247 | ||
8248 | if (sizeof (struct tree_exp) + 5 * sizeof (tree) | |
8249 | > sizeof (struct tree_decl) | |
8250 | || sizeof (struct tree_type) > sizeof (struct tree_decl)) | |
8251 | abort (); | |
8252 | if (expr == NULL) | |
8253 | return; | |
8254 | slot = htab_find_slot (ht, expr, INSERT); | |
8255 | if (*slot != NULL) | |
8256 | return; | |
8257 | *slot = expr; | |
8258 | code = TREE_CODE (expr); | |
8259 | if (code == SAVE_EXPR && SAVE_EXPR_NOPLACEHOLDER (expr)) | |
8260 | { | |
8261 | /* Allow SAVE_EXPR_NOPLACEHOLDER flag to be modified. */ | |
8262 | memcpy (buf, expr, tree_size (expr)); | |
8263 | expr = (tree) buf; | |
8264 | SAVE_EXPR_NOPLACEHOLDER (expr) = 0; | |
8265 | } | |
8266 | else if (TREE_CODE_CLASS (code) == 'd' && DECL_ASSEMBLER_NAME_SET_P (expr)) | |
8267 | { | |
8268 | /* Allow DECL_ASSEMBLER_NAME to be modified. */ | |
8269 | memcpy (buf, expr, tree_size (expr)); | |
8270 | expr = (tree) buf; | |
8271 | SET_DECL_ASSEMBLER_NAME (expr, NULL); | |
8272 | } | |
8273 | else if (TREE_CODE_CLASS (code) == 't' | |
8274 | && (TYPE_POINTER_TO (expr) || TYPE_REFERENCE_TO (expr))) | |
8275 | { | |
8276 | /* Allow TYPE_POINTER_TO and TYPE_REFERENCE_TO to be modified. */ | |
8277 | memcpy (buf, expr, tree_size (expr)); | |
8278 | expr = (tree) buf; | |
8279 | TYPE_POINTER_TO (expr) = NULL; | |
8280 | TYPE_REFERENCE_TO (expr) = NULL; | |
8281 | } | |
8282 | md5_process_bytes (expr, tree_size (expr), ctx); | |
8283 | fold_checksum_tree (TREE_TYPE (expr), ctx, ht); | |
8284 | if (TREE_CODE_CLASS (code) != 't' && TREE_CODE_CLASS (code) != 'd') | |
8285 | fold_checksum_tree (TREE_CHAIN (expr), ctx, ht); | |
8286 | len = TREE_CODE_LENGTH (code); | |
8287 | switch (TREE_CODE_CLASS (code)) | |
8288 | { | |
8289 | case 'c': | |
8290 | switch (code) | |
8291 | { | |
8292 | case STRING_CST: | |
8293 | md5_process_bytes (TREE_STRING_POINTER (expr), | |
8294 | TREE_STRING_LENGTH (expr), ctx); | |
8295 | break; | |
8296 | case COMPLEX_CST: | |
8297 | fold_checksum_tree (TREE_REALPART (expr), ctx, ht); | |
8298 | fold_checksum_tree (TREE_IMAGPART (expr), ctx, ht); | |
8299 | break; | |
8300 | case VECTOR_CST: | |
8301 | fold_checksum_tree (TREE_VECTOR_CST_ELTS (expr), ctx, ht); | |
8302 | break; | |
8303 | default: | |
8304 | break; | |
8305 | } | |
8306 | break; | |
8307 | case 'x': | |
8308 | switch (code) | |
8309 | { | |
8310 | case TREE_LIST: | |
8311 | fold_checksum_tree (TREE_PURPOSE (expr), ctx, ht); | |
8312 | fold_checksum_tree (TREE_VALUE (expr), ctx, ht); | |
8313 | break; | |
8314 | case TREE_VEC: | |
8315 | for (i = 0; i < TREE_VEC_LENGTH (expr); ++i) | |
8316 | fold_checksum_tree (TREE_VEC_ELT (expr, i), ctx, ht); | |
8317 | break; | |
8318 | default: | |
8319 | break; | |
8320 | } | |
8321 | break; | |
8322 | case 'e': | |
8323 | switch (code) | |
8324 | { | |
8325 | case SAVE_EXPR: len = 2; break; | |
8326 | case GOTO_SUBROUTINE_EXPR: len = 0; break; | |
8327 | case RTL_EXPR: len = 0; break; | |
8328 | case WITH_CLEANUP_EXPR: len = 2; break; | |
8329 | default: break; | |
8330 | } | |
8331 | /* FALLTHROUGH */ | |
8332 | case 'r': | |
8333 | case '<': | |
8334 | case '1': | |
8335 | case '2': | |
8336 | case 's': | |
8337 | for (i = 0; i < len; ++i) | |
8338 | fold_checksum_tree (TREE_OPERAND (expr, i), ctx, ht); | |
8339 | break; | |
8340 | case 'd': | |
8341 | fold_checksum_tree (DECL_SIZE (expr), ctx, ht); | |
8342 | fold_checksum_tree (DECL_SIZE_UNIT (expr), ctx, ht); | |
8343 | fold_checksum_tree (DECL_NAME (expr), ctx, ht); | |
8344 | fold_checksum_tree (DECL_CONTEXT (expr), ctx, ht); | |
8345 | fold_checksum_tree (DECL_ARGUMENTS (expr), ctx, ht); | |
8346 | fold_checksum_tree (DECL_RESULT_FLD (expr), ctx, ht); | |
8347 | fold_checksum_tree (DECL_INITIAL (expr), ctx, ht); | |
8348 | fold_checksum_tree (DECL_ABSTRACT_ORIGIN (expr), ctx, ht); | |
8349 | fold_checksum_tree (DECL_SECTION_NAME (expr), ctx, ht); | |
8350 | fold_checksum_tree (DECL_ATTRIBUTES (expr), ctx, ht); | |
8351 | fold_checksum_tree (DECL_VINDEX (expr), ctx, ht); | |
8352 | break; | |
8353 | case 't': | |
8354 | fold_checksum_tree (TYPE_VALUES (expr), ctx, ht); | |
8355 | fold_checksum_tree (TYPE_SIZE (expr), ctx, ht); | |
8356 | fold_checksum_tree (TYPE_SIZE_UNIT (expr), ctx, ht); | |
8357 | fold_checksum_tree (TYPE_ATTRIBUTES (expr), ctx, ht); | |
8358 | fold_checksum_tree (TYPE_NAME (expr), ctx, ht); | |
8359 | fold_checksum_tree (TYPE_MIN_VALUE (expr), ctx, ht); | |
8360 | fold_checksum_tree (TYPE_MAX_VALUE (expr), ctx, ht); | |
8361 | fold_checksum_tree (TYPE_MAIN_VARIANT (expr), ctx, ht); | |
8362 | fold_checksum_tree (TYPE_BINFO (expr), ctx, ht); | |
8363 | fold_checksum_tree (TYPE_CONTEXT (expr), ctx, ht); | |
8364 | break; | |
8365 | default: | |
8366 | break; | |
8367 | } | |
8368 | } | |
8369 | ||
8370 | #endif | |
8371 | ||
a98ebe2e | 8372 | /* Perform constant folding and related simplification of initializer |
3e4093b6 RS |
8373 | expression EXPR. This behaves identically to "fold" but ignores |
8374 | potential run-time traps and exceptions that fold must preserve. */ | |
8375 | ||
8376 | tree | |
8377 | fold_initializer (tree expr) | |
8378 | { | |
8379 | int saved_signaling_nans = flag_signaling_nans; | |
8380 | int saved_trapping_math = flag_trapping_math; | |
8381 | int saved_trapv = flag_trapv; | |
8382 | tree result; | |
8383 | ||
8384 | flag_signaling_nans = 0; | |
8385 | flag_trapping_math = 0; | |
8386 | flag_trapv = 0; | |
8387 | ||
8388 | result = fold (expr); | |
8389 | ||
8390 | flag_signaling_nans = saved_signaling_nans; | |
8391 | flag_trapping_math = saved_trapping_math; | |
8392 | flag_trapv = saved_trapv; | |
8393 | ||
8394 | return result; | |
8395 | } | |
8396 | ||
c5c76735 JL |
8397 | /* Determine if first argument is a multiple of second argument. Return 0 if |
8398 | it is not, or we cannot easily determined it to be. | |
39dfb55a | 8399 | |
c5c76735 JL |
8400 | An example of the sort of thing we care about (at this point; this routine |
8401 | could surely be made more general, and expanded to do what the *_DIV_EXPR's | |
8402 | fold cases do now) is discovering that | |
39dfb55a JL |
8403 | |
8404 | SAVE_EXPR (I) * SAVE_EXPR (J * 8) | |
8405 | ||
8406 | is a multiple of | |
8407 | ||
8408 | SAVE_EXPR (J * 8) | |
8409 | ||
c5c76735 | 8410 | when we know that the two SAVE_EXPR (J * 8) nodes are the same node. |
39dfb55a JL |
8411 | |
8412 | This code also handles discovering that | |
8413 | ||
8414 | SAVE_EXPR (I) * SAVE_EXPR (J * 8) | |
8415 | ||
c5c76735 | 8416 | is a multiple of 8 so we don't have to worry about dealing with a |
39dfb55a JL |
8417 | possible remainder. |
8418 | ||
c5c76735 JL |
8419 | Note that we *look* inside a SAVE_EXPR only to determine how it was |
8420 | calculated; it is not safe for fold to do much of anything else with the | |
8421 | internals of a SAVE_EXPR, since it cannot know when it will be evaluated | |
8422 | at run time. For example, the latter example above *cannot* be implemented | |
8423 | as SAVE_EXPR (I) * J or any variant thereof, since the value of J at | |
8424 | evaluation time of the original SAVE_EXPR is not necessarily the same at | |
8425 | the time the new expression is evaluated. The only optimization of this | |
39dfb55a JL |
8426 | sort that would be valid is changing |
8427 | ||
8428 | SAVE_EXPR (I) * SAVE_EXPR (SAVE_EXPR (J) * 8) | |
39dfb55a | 8429 | |
c5c76735 | 8430 | divided by 8 to |
39dfb55a JL |
8431 | |
8432 | SAVE_EXPR (I) * SAVE_EXPR (J) | |
8433 | ||
8434 | (where the same SAVE_EXPR (J) is used in the original and the | |
8435 | transformed version). */ | |
8436 | ||
8437 | static int | |
fa8db1f7 | 8438 | multiple_of_p (tree type, tree top, tree bottom) |
39dfb55a JL |
8439 | { |
8440 | if (operand_equal_p (top, bottom, 0)) | |
8441 | return 1; | |
8442 | ||
8443 | if (TREE_CODE (type) != INTEGER_TYPE) | |
8444 | return 0; | |
8445 | ||
8446 | switch (TREE_CODE (top)) | |
8447 | { | |
8448 | case MULT_EXPR: | |
8449 | return (multiple_of_p (type, TREE_OPERAND (top, 0), bottom) | |
8450 | || multiple_of_p (type, TREE_OPERAND (top, 1), bottom)); | |
8451 | ||
8452 | case PLUS_EXPR: | |
8453 | case MINUS_EXPR: | |
8454 | return (multiple_of_p (type, TREE_OPERAND (top, 0), bottom) | |
8455 | && multiple_of_p (type, TREE_OPERAND (top, 1), bottom)); | |
8456 | ||
fba2c0cd JJ |
8457 | case LSHIFT_EXPR: |
8458 | if (TREE_CODE (TREE_OPERAND (top, 1)) == INTEGER_CST) | |
8459 | { | |
8460 | tree op1, t1; | |
8461 | ||
8462 | op1 = TREE_OPERAND (top, 1); | |
8463 | /* const_binop may not detect overflow correctly, | |
8464 | so check for it explicitly here. */ | |
8465 | if (TYPE_PRECISION (TREE_TYPE (size_one_node)) | |
8466 | > TREE_INT_CST_LOW (op1) | |
8467 | && TREE_INT_CST_HIGH (op1) == 0 | |
8468 | && 0 != (t1 = convert (type, | |
8469 | const_binop (LSHIFT_EXPR, size_one_node, | |
8470 | op1, 0))) | |
8471 | && ! TREE_OVERFLOW (t1)) | |
8472 | return multiple_of_p (type, t1, bottom); | |
8473 | } | |
8474 | return 0; | |
8475 | ||
39dfb55a | 8476 | case NOP_EXPR: |
c5c76735 | 8477 | /* Can't handle conversions from non-integral or wider integral type. */ |
39dfb55a JL |
8478 | if ((TREE_CODE (TREE_TYPE (TREE_OPERAND (top, 0))) != INTEGER_TYPE) |
8479 | || (TYPE_PRECISION (type) | |
8480 | < TYPE_PRECISION (TREE_TYPE (TREE_OPERAND (top, 0))))) | |
8481 | return 0; | |
c5c76735 | 8482 | |
30f7a378 | 8483 | /* .. fall through ... */ |
c5c76735 | 8484 | |
39dfb55a JL |
8485 | case SAVE_EXPR: |
8486 | return multiple_of_p (type, TREE_OPERAND (top, 0), bottom); | |
8487 | ||
8488 | case INTEGER_CST: | |
fba2c0cd JJ |
8489 | if (TREE_CODE (bottom) != INTEGER_CST |
8490 | || (TREE_UNSIGNED (type) | |
8491 | && (tree_int_cst_sgn (top) < 0 | |
8492 | || tree_int_cst_sgn (bottom) < 0))) | |
39dfb55a JL |
8493 | return 0; |
8494 | return integer_zerop (const_binop (TRUNC_MOD_EXPR, | |
8495 | top, bottom, 0)); | |
8496 | ||
8497 | default: | |
8498 | return 0; | |
8499 | } | |
8500 | } | |
a36556a8 ZW |
8501 | |
8502 | /* Return true if `t' is known to be non-negative. */ | |
8503 | ||
8504 | int | |
fa8db1f7 | 8505 | tree_expr_nonnegative_p (tree t) |
a36556a8 ZW |
8506 | { |
8507 | switch (TREE_CODE (t)) | |
8508 | { | |
88e3805d | 8509 | case ABS_EXPR: |
88e3805d | 8510 | return 1; |
7dba8395 | 8511 | |
a36556a8 ZW |
8512 | case INTEGER_CST: |
8513 | return tree_int_cst_sgn (t) >= 0; | |
f7df23be RS |
8514 | |
8515 | case REAL_CST: | |
8516 | return ! REAL_VALUE_NEGATIVE (TREE_REAL_CST (t)); | |
8517 | ||
8518 | case PLUS_EXPR: | |
96f26e41 RS |
8519 | if (FLOAT_TYPE_P (TREE_TYPE (t))) |
8520 | return tree_expr_nonnegative_p (TREE_OPERAND (t, 0)) | |
8521 | && tree_expr_nonnegative_p (TREE_OPERAND (t, 1)); | |
8522 | ||
e15bb5c6 | 8523 | /* zero_extend(x) + zero_extend(y) is non-negative if x and y are |
e2cca9be | 8524 | both unsigned and at least 2 bits shorter than the result. */ |
96f26e41 RS |
8525 | if (TREE_CODE (TREE_TYPE (t)) == INTEGER_TYPE |
8526 | && TREE_CODE (TREE_OPERAND (t, 0)) == NOP_EXPR | |
8527 | && TREE_CODE (TREE_OPERAND (t, 1)) == NOP_EXPR) | |
8528 | { | |
8529 | tree inner1 = TREE_TYPE (TREE_OPERAND (TREE_OPERAND (t, 0), 0)); | |
8530 | tree inner2 = TREE_TYPE (TREE_OPERAND (TREE_OPERAND (t, 1), 0)); | |
8531 | if (TREE_CODE (inner1) == INTEGER_TYPE && TREE_UNSIGNED (inner1) | |
8532 | && TREE_CODE (inner2) == INTEGER_TYPE && TREE_UNSIGNED (inner2)) | |
8533 | { | |
8534 | unsigned int prec = MAX (TYPE_PRECISION (inner1), | |
8535 | TYPE_PRECISION (inner2)) + 1; | |
8536 | return prec < TYPE_PRECISION (TREE_TYPE (t)); | |
8537 | } | |
8538 | } | |
8539 | break; | |
f7df23be RS |
8540 | |
8541 | case MULT_EXPR: | |
8542 | if (FLOAT_TYPE_P (TREE_TYPE (t))) | |
8543 | { | |
8544 | /* x * x for floating point x is always non-negative. */ | |
8545 | if (operand_equal_p (TREE_OPERAND (t, 0), TREE_OPERAND (t, 1), 0)) | |
8546 | return 1; | |
8547 | return tree_expr_nonnegative_p (TREE_OPERAND (t, 0)) | |
8548 | && tree_expr_nonnegative_p (TREE_OPERAND (t, 1)); | |
8549 | } | |
96f26e41 | 8550 | |
e15bb5c6 | 8551 | /* zero_extend(x) * zero_extend(y) is non-negative if x and y are |
96f26e41 RS |
8552 | both unsigned and their total bits is shorter than the result. */ |
8553 | if (TREE_CODE (TREE_TYPE (t)) == INTEGER_TYPE | |
8554 | && TREE_CODE (TREE_OPERAND (t, 0)) == NOP_EXPR | |
8555 | && TREE_CODE (TREE_OPERAND (t, 1)) == NOP_EXPR) | |
8556 | { | |
8557 | tree inner1 = TREE_TYPE (TREE_OPERAND (TREE_OPERAND (t, 0), 0)); | |
8558 | tree inner2 = TREE_TYPE (TREE_OPERAND (TREE_OPERAND (t, 1), 0)); | |
8559 | if (TREE_CODE (inner1) == INTEGER_TYPE && TREE_UNSIGNED (inner1) | |
8560 | && TREE_CODE (inner2) == INTEGER_TYPE && TREE_UNSIGNED (inner2)) | |
8561 | return TYPE_PRECISION (inner1) + TYPE_PRECISION (inner2) | |
8562 | < TYPE_PRECISION (TREE_TYPE (t)); | |
8563 | } | |
f7df23be RS |
8564 | return 0; |
8565 | ||
ada11335 KG |
8566 | case TRUNC_DIV_EXPR: |
8567 | case CEIL_DIV_EXPR: | |
8568 | case FLOOR_DIV_EXPR: | |
8569 | case ROUND_DIV_EXPR: | |
8570 | return tree_expr_nonnegative_p (TREE_OPERAND (t, 0)) | |
96f26e41 RS |
8571 | && tree_expr_nonnegative_p (TREE_OPERAND (t, 1)); |
8572 | ||
ada11335 KG |
8573 | case TRUNC_MOD_EXPR: |
8574 | case CEIL_MOD_EXPR: | |
8575 | case FLOOR_MOD_EXPR: | |
8576 | case ROUND_MOD_EXPR: | |
8577 | return tree_expr_nonnegative_p (TREE_OPERAND (t, 0)); | |
96f26e41 RS |
8578 | |
8579 | case RDIV_EXPR: | |
8580 | return tree_expr_nonnegative_p (TREE_OPERAND (t, 0)) | |
8581 | && tree_expr_nonnegative_p (TREE_OPERAND (t, 1)); | |
8582 | ||
8583 | case NOP_EXPR: | |
8584 | { | |
8585 | tree inner_type = TREE_TYPE (TREE_OPERAND (t, 0)); | |
8586 | tree outer_type = TREE_TYPE (t); | |
8587 | ||
8588 | if (TREE_CODE (outer_type) == REAL_TYPE) | |
8589 | { | |
8590 | if (TREE_CODE (inner_type) == REAL_TYPE) | |
8591 | return tree_expr_nonnegative_p (TREE_OPERAND (t, 0)); | |
8592 | if (TREE_CODE (inner_type) == INTEGER_TYPE) | |
8593 | { | |
8594 | if (TREE_UNSIGNED (inner_type)) | |
8595 | return 1; | |
8596 | return tree_expr_nonnegative_p (TREE_OPERAND (t, 0)); | |
8597 | } | |
8598 | } | |
8599 | else if (TREE_CODE (outer_type) == INTEGER_TYPE) | |
8600 | { | |
8601 | if (TREE_CODE (inner_type) == REAL_TYPE) | |
8602 | return tree_expr_nonnegative_p (TREE_OPERAND (t,0)); | |
8603 | if (TREE_CODE (inner_type) == INTEGER_TYPE) | |
8604 | return TYPE_PRECISION (inner_type) < TYPE_PRECISION (outer_type) | |
8605 | && TREE_UNSIGNED (inner_type); | |
8606 | } | |
8607 | } | |
8608 | break; | |
8609 | ||
a36556a8 ZW |
8610 | case COND_EXPR: |
8611 | return tree_expr_nonnegative_p (TREE_OPERAND (t, 1)) | |
8612 | && tree_expr_nonnegative_p (TREE_OPERAND (t, 2)); | |
88e3805d KG |
8613 | case COMPOUND_EXPR: |
8614 | return tree_expr_nonnegative_p (TREE_OPERAND (t, 1)); | |
8615 | case MIN_EXPR: | |
8616 | return tree_expr_nonnegative_p (TREE_OPERAND (t, 0)) | |
dd3f0101 | 8617 | && tree_expr_nonnegative_p (TREE_OPERAND (t, 1)); |
88e3805d KG |
8618 | case MAX_EXPR: |
8619 | return tree_expr_nonnegative_p (TREE_OPERAND (t, 0)) | |
dd3f0101 | 8620 | || tree_expr_nonnegative_p (TREE_OPERAND (t, 1)); |
88e3805d KG |
8621 | case MODIFY_EXPR: |
8622 | return tree_expr_nonnegative_p (TREE_OPERAND (t, 1)); | |
a36556a8 ZW |
8623 | case BIND_EXPR: |
8624 | return tree_expr_nonnegative_p (TREE_OPERAND (t, 1)); | |
ada11335 KG |
8625 | case SAVE_EXPR: |
8626 | return tree_expr_nonnegative_p (TREE_OPERAND (t, 0)); | |
8627 | case NON_LVALUE_EXPR: | |
8628 | return tree_expr_nonnegative_p (TREE_OPERAND (t, 0)); | |
0a9530a9 RS |
8629 | case FLOAT_EXPR: |
8630 | return tree_expr_nonnegative_p (TREE_OPERAND (t, 0)); | |
a36556a8 ZW |
8631 | case RTL_EXPR: |
8632 | return rtl_expr_nonnegative_p (RTL_EXPR_RTL (t)); | |
dd3f0101 | 8633 | |
07bae5ad | 8634 | case CALL_EXPR: |
2f503025 JM |
8635 | { |
8636 | tree fndecl = get_callee_fndecl (t); | |
8637 | tree arglist = TREE_OPERAND (t, 1); | |
8638 | if (fndecl | |
8639 | && DECL_BUILT_IN (fndecl) | |
8640 | && DECL_BUILT_IN_CLASS (fndecl) != BUILT_IN_MD) | |
8641 | switch (DECL_FUNCTION_CODE (fndecl)) | |
8642 | { | |
8643 | case BUILT_IN_CABS: | |
8644 | case BUILT_IN_CABSL: | |
8645 | case BUILT_IN_CABSF: | |
8646 | case BUILT_IN_EXP: | |
8647 | case BUILT_IN_EXPF: | |
8648 | case BUILT_IN_EXPL: | |
f7657db9 KG |
8649 | case BUILT_IN_EXP2: |
8650 | case BUILT_IN_EXP2F: | |
8651 | case BUILT_IN_EXP2L: | |
8652 | case BUILT_IN_EXP10: | |
8653 | case BUILT_IN_EXP10F: | |
8654 | case BUILT_IN_EXP10L: | |
2f503025 JM |
8655 | case BUILT_IN_FABS: |
8656 | case BUILT_IN_FABSF: | |
8657 | case BUILT_IN_FABSL: | |
96123432 RS |
8658 | case BUILT_IN_FFS: |
8659 | case BUILT_IN_FFSL: | |
8660 | case BUILT_IN_FFSLL: | |
8661 | case BUILT_IN_PARITY: | |
8662 | case BUILT_IN_PARITYL: | |
8663 | case BUILT_IN_PARITYLL: | |
8664 | case BUILT_IN_POPCOUNT: | |
8665 | case BUILT_IN_POPCOUNTL: | |
8666 | case BUILT_IN_POPCOUNTLL: | |
8667 | case BUILT_IN_POW10: | |
8668 | case BUILT_IN_POW10F: | |
8669 | case BUILT_IN_POW10L: | |
2f503025 JM |
8670 | case BUILT_IN_SQRT: |
8671 | case BUILT_IN_SQRTF: | |
8672 | case BUILT_IN_SQRTL: | |
8673 | return 1; | |
8674 | ||
8675 | case BUILT_IN_ATAN: | |
8676 | case BUILT_IN_ATANF: | |
8677 | case BUILT_IN_ATANL: | |
8678 | case BUILT_IN_CEIL: | |
8679 | case BUILT_IN_CEILF: | |
8680 | case BUILT_IN_CEILL: | |
8681 | case BUILT_IN_FLOOR: | |
8682 | case BUILT_IN_FLOORF: | |
8683 | case BUILT_IN_FLOORL: | |
8684 | case BUILT_IN_NEARBYINT: | |
8685 | case BUILT_IN_NEARBYINTF: | |
8686 | case BUILT_IN_NEARBYINTL: | |
8687 | case BUILT_IN_ROUND: | |
8688 | case BUILT_IN_ROUNDF: | |
8689 | case BUILT_IN_ROUNDL: | |
8690 | case BUILT_IN_TRUNC: | |
8691 | case BUILT_IN_TRUNCF: | |
8692 | case BUILT_IN_TRUNCL: | |
8693 | return tree_expr_nonnegative_p (TREE_VALUE (arglist)); | |
8694 | ||
8695 | case BUILT_IN_POW: | |
8696 | case BUILT_IN_POWF: | |
8697 | case BUILT_IN_POWL: | |
8698 | return tree_expr_nonnegative_p (TREE_VALUE (arglist)); | |
07bae5ad | 8699 | |
2f503025 JM |
8700 | default: |
8701 | break; | |
8702 | } | |
8703 | } | |
07bae5ad | 8704 | |
71c0e7fc | 8705 | /* ... fall through ... */ |
07bae5ad | 8706 | |
a36556a8 | 8707 | default: |
9d2dc7da KG |
8708 | if (truth_value_p (TREE_CODE (t))) |
8709 | /* Truth values evaluate to 0 or 1, which is nonnegative. */ | |
8710 | return 1; | |
a36556a8 | 8711 | } |
96f26e41 RS |
8712 | |
8713 | /* We don't know sign of `t', so be conservative and return false. */ | |
8714 | return 0; | |
a36556a8 ZW |
8715 | } |
8716 | ||
8717 | /* Return true if `r' is known to be non-negative. | |
8718 | Only handles constants at the moment. */ | |
8719 | ||
8720 | int | |
fa8db1f7 | 8721 | rtl_expr_nonnegative_p (rtx r) |
a36556a8 ZW |
8722 | { |
8723 | switch (GET_CODE (r)) | |
8724 | { | |
8725 | case CONST_INT: | |
8726 | return INTVAL (r) >= 0; | |
8727 | ||
8728 | case CONST_DOUBLE: | |
8729 | if (GET_MODE (r) == VOIDmode) | |
8730 | return CONST_DOUBLE_HIGH (r) >= 0; | |
8731 | return 0; | |
8732 | ||
69ef87e2 AH |
8733 | case CONST_VECTOR: |
8734 | { | |
8735 | int units, i; | |
8736 | rtx elt; | |
8737 | ||
8738 | units = CONST_VECTOR_NUNITS (r); | |
8739 | ||
8740 | for (i = 0; i < units; ++i) | |
8741 | { | |
8742 | elt = CONST_VECTOR_ELT (r, i); | |
8743 | if (!rtl_expr_nonnegative_p (elt)) | |
8744 | return 0; | |
8745 | } | |
8746 | ||
8747 | return 1; | |
8748 | } | |
8749 | ||
a36556a8 ZW |
8750 | case SYMBOL_REF: |
8751 | case LABEL_REF: | |
8752 | /* These are always nonnegative. */ | |
8753 | return 1; | |
8754 | ||
8755 | default: | |
8756 | return 0; | |
8757 | } | |
8758 | } | |
e2500fed GK |
8759 | |
8760 | #include "gt-fold-const.h" |