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Commit | Line | Data |
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6d716ca8 | 1 | /* Fold a constant sub-tree into a single node for C-compiler |
f8dac6eb | 2 | Copyright (C) 1987, 88, 92-97, 1998 Free Software Foundation, Inc. |
6d716ca8 RS |
3 | |
4 | This file is part of GNU CC. | |
5 | ||
6 | GNU CC is free software; you can redistribute it and/or modify | |
7 | it under the terms of the GNU General Public License as published by | |
8 | the Free Software Foundation; either version 2, or (at your option) | |
9 | any later version. | |
10 | ||
11 | GNU CC is distributed in the hope that it will be useful, | |
12 | but WITHOUT ANY WARRANTY; without even the implied warranty of | |
13 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | |
14 | GNU General Public License for more details. | |
15 | ||
16 | You should have received a copy of the GNU General Public License | |
17 | along with GNU CC; see the file COPYING. If not, write to | |
a35311b0 RK |
18 | the Free Software Foundation, 59 Temple Place - Suite 330, |
19 | Boston, MA 02111-1307, USA. */ | |
6d716ca8 | 20 | |
6dc42e49 | 21 | /*@@ This file should be rewritten to use an arbitrary precision |
6d716ca8 RS |
22 | @@ representation for "struct tree_int_cst" and "struct tree_real_cst". |
23 | @@ Perhaps the routines could also be used for bc/dc, and made a lib. | |
24 | @@ The routines that translate from the ap rep should | |
25 | @@ warn if precision et. al. is lost. | |
26 | @@ This would also make life easier when this technology is used | |
27 | @@ for cross-compilers. */ | |
28 | ||
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" |
6d716ca8 | 47 | #include <setjmp.h> |
6d716ca8 RS |
48 | #include "flags.h" |
49 | #include "tree.h" | |
efe3eb65 | 50 | #include "rtl.h" |
10f0ad3d | 51 | #include "toplev.h" |
6d716ca8 | 52 | |
7c7b029d RS |
53 | /* Handle floating overflow for `const_binop'. */ |
54 | static jmp_buf float_error; | |
55 | ||
ebde8a27 RK |
56 | static void encode PROTO((HOST_WIDE_INT *, |
57 | HOST_WIDE_INT, HOST_WIDE_INT)); | |
58 | static void decode PROTO((HOST_WIDE_INT *, | |
59 | HOST_WIDE_INT *, HOST_WIDE_INT *)); | |
60 | int div_and_round_double PROTO((enum tree_code, int, HOST_WIDE_INT, | |
6dc7571d RK |
61 | HOST_WIDE_INT, HOST_WIDE_INT, |
62 | HOST_WIDE_INT, HOST_WIDE_INT *, | |
63 | HOST_WIDE_INT *, HOST_WIDE_INT *, | |
64 | HOST_WIDE_INT *)); | |
ebde8a27 RK |
65 | static int split_tree PROTO((tree, enum tree_code, tree *, |
66 | tree *, int *)); | |
e9a25f70 | 67 | static tree int_const_binop PROTO((enum tree_code, tree, tree, int, int)); |
ebde8a27 RK |
68 | static tree const_binop PROTO((enum tree_code, tree, tree, int)); |
69 | static tree fold_convert PROTO((tree, tree)); | |
6dc7571d RK |
70 | static enum tree_code invert_tree_comparison PROTO((enum tree_code)); |
71 | static enum tree_code swap_tree_comparison PROTO((enum tree_code)); | |
ebde8a27 | 72 | static int truth_value_p PROTO((enum tree_code)); |
6dc7571d | 73 | static int operand_equal_for_comparison_p PROTO((tree, tree, tree)); |
ebde8a27 RK |
74 | static int twoval_comparison_p PROTO((tree, tree *, tree *, int *)); |
75 | static tree eval_subst PROTO((tree, tree, tree, tree, tree)); | |
76 | static tree omit_one_operand PROTO((tree, tree, tree)); | |
4ab3cb65 | 77 | static tree pedantic_omit_one_operand PROTO((tree, tree, tree)); |
6dc7571d | 78 | static tree distribute_bit_expr PROTO((enum tree_code, tree, tree, tree)); |
ebde8a27 | 79 | static tree make_bit_field_ref PROTO((tree, tree, int, int, int)); |
6dc7571d RK |
80 | static tree optimize_bit_field_compare PROTO((enum tree_code, tree, |
81 | tree, tree)); | |
82 | static tree decode_field_reference PROTO((tree, int *, int *, | |
83 | enum machine_mode *, int *, | |
d4453ee5 | 84 | int *, tree *, tree *)); |
ebde8a27 RK |
85 | static int all_ones_mask_p PROTO((tree, int)); |
86 | static int simple_operand_p PROTO((tree)); | |
87 | static tree range_binop PROTO((enum tree_code, tree, tree, int, | |
88 | tree, int)); | |
89 | static tree make_range PROTO((tree, int *, tree *, tree *)); | |
90 | static tree build_range_check PROTO((tree, tree, int, tree, tree)); | |
91 | static int merge_ranges PROTO((int *, tree *, tree *, int, tree, tree, | |
92 | int, tree, tree)); | |
93 | static tree fold_range_test PROTO((tree)); | |
94 | static tree unextend PROTO((tree, int, int, tree)); | |
95 | static tree fold_truthop PROTO((enum tree_code, tree, tree, tree)); | |
b5f3b6b6 | 96 | static tree strip_compound_expr PROTO((tree, tree)); |
39dfb55a | 97 | static int multiple_of_p PROTO((tree, tree, tree)); |
f628873f | 98 | static tree constant_boolean_node PROTO((int, tree)); |
d35357ed RS |
99 | |
100 | #ifndef BRANCH_COST | |
101 | #define BRANCH_COST 1 | |
102 | #endif | |
fe3e8e40 | 103 | |
fe3e8e40 RS |
104 | /* Suppose A1 + B1 = SUM1, using 2's complement arithmetic ignoring overflow. |
105 | Suppose A, B and SUM have the same respective signs as A1, B1, and SUM1. | |
106 | Then this yields nonzero if overflow occurred during the addition. | |
107 | Overflow occurs if A and B have the same sign, but A and SUM differ in sign. | |
108 | Use `^' to test whether signs differ, and `< 0' to isolate the sign. */ | |
109 | #define overflow_sum_sign(a, b, sum) ((~((a) ^ (b)) & ((a) ^ (sum))) < 0) | |
6d716ca8 | 110 | \f |
906c4e36 | 111 | /* To do constant folding on INTEGER_CST nodes requires two-word arithmetic. |
37bdb7e3 TG |
112 | We do that by representing the two-word integer in 4 words, with only |
113 | HOST_BITS_PER_WIDE_INT/2 bits stored in each word, as a positive number. */ | |
114 | ||
115 | #define LOWPART(x) \ | |
116 | ((x) & (((unsigned HOST_WIDE_INT) 1 << (HOST_BITS_PER_WIDE_INT/2)) - 1)) | |
117 | #define HIGHPART(x) \ | |
118 | ((unsigned HOST_WIDE_INT) (x) >> HOST_BITS_PER_WIDE_INT/2) | |
119 | #define BASE ((unsigned HOST_WIDE_INT) 1 << HOST_BITS_PER_WIDE_INT/2) | |
6d716ca8 | 120 | |
37bdb7e3 | 121 | /* Unpack a two-word integer into 4 words. |
906c4e36 | 122 | LOW and HI are the integer, as two `HOST_WIDE_INT' pieces. |
37bdb7e3 | 123 | WORDS points to the array of HOST_WIDE_INTs. */ |
6d716ca8 RS |
124 | |
125 | static void | |
37bdb7e3 TG |
126 | encode (words, low, hi) |
127 | HOST_WIDE_INT *words; | |
906c4e36 | 128 | HOST_WIDE_INT low, hi; |
6d716ca8 | 129 | { |
37bdb7e3 TG |
130 | words[0] = LOWPART (low); |
131 | words[1] = HIGHPART (low); | |
132 | words[2] = LOWPART (hi); | |
133 | words[3] = HIGHPART (hi); | |
6d716ca8 RS |
134 | } |
135 | ||
37bdb7e3 TG |
136 | /* Pack an array of 4 words into a two-word integer. |
137 | WORDS points to the array of words. | |
906c4e36 | 138 | The integer is stored into *LOW and *HI as two `HOST_WIDE_INT' pieces. */ |
6d716ca8 RS |
139 | |
140 | static void | |
37bdb7e3 TG |
141 | decode (words, low, hi) |
142 | HOST_WIDE_INT *words; | |
906c4e36 | 143 | HOST_WIDE_INT *low, *hi; |
6d716ca8 | 144 | { |
37bdb7e3 TG |
145 | *low = words[0] | words[1] * BASE; |
146 | *hi = words[2] | words[3] * BASE; | |
6d716ca8 RS |
147 | } |
148 | \f | |
149 | /* Make the integer constant T valid for its type | |
150 | by setting to 0 or 1 all the bits in the constant | |
e0f776fb RS |
151 | that don't belong in the type. |
152 | Yield 1 if a signed overflow occurs, 0 otherwise. | |
a4d8855c | 153 | If OVERFLOW is nonzero, a signed overflow has already occurred |
649ff3b4 RK |
154 | in calculating T, so propagate it. |
155 | ||
156 | Make the real constant T valid for its type by calling CHECK_FLOAT_VALUE, | |
157 | if it exists. */ | |
6d716ca8 | 158 | |
e0f776fb RS |
159 | int |
160 | force_fit_type (t, overflow) | |
6d716ca8 | 161 | tree t; |
e0f776fb | 162 | int overflow; |
6d716ca8 | 163 | { |
ef2bf0c0 RS |
164 | HOST_WIDE_INT low, high; |
165 | register int prec; | |
6d716ca8 | 166 | |
649ff3b4 RK |
167 | if (TREE_CODE (t) == REAL_CST) |
168 | { | |
169 | #ifdef CHECK_FLOAT_VALUE | |
170 | CHECK_FLOAT_VALUE (TYPE_MODE (TREE_TYPE (t)), TREE_REAL_CST (t), | |
171 | overflow); | |
172 | #endif | |
173 | return overflow; | |
174 | } | |
175 | ||
176 | else if (TREE_CODE (t) != INTEGER_CST) | |
ef2bf0c0 RS |
177 | return overflow; |
178 | ||
179 | low = TREE_INT_CST_LOW (t); | |
180 | high = TREE_INT_CST_HIGH (t); | |
42f769c1 | 181 | |
e5e809f4 | 182 | if (POINTER_TYPE_P (TREE_TYPE (t))) |
6d716ca8 | 183 | prec = POINTER_SIZE; |
ef2bf0c0 RS |
184 | else |
185 | prec = TYPE_PRECISION (TREE_TYPE (t)); | |
6d716ca8 RS |
186 | |
187 | /* First clear all bits that are beyond the type's precision. */ | |
188 | ||
906c4e36 | 189 | if (prec == 2 * HOST_BITS_PER_WIDE_INT) |
6d716ca8 | 190 | ; |
906c4e36 | 191 | else if (prec > HOST_BITS_PER_WIDE_INT) |
6d716ca8 RS |
192 | { |
193 | TREE_INT_CST_HIGH (t) | |
906c4e36 | 194 | &= ~((HOST_WIDE_INT) (-1) << (prec - HOST_BITS_PER_WIDE_INT)); |
6d716ca8 RS |
195 | } |
196 | else | |
197 | { | |
198 | TREE_INT_CST_HIGH (t) = 0; | |
906c4e36 RK |
199 | if (prec < HOST_BITS_PER_WIDE_INT) |
200 | TREE_INT_CST_LOW (t) &= ~((HOST_WIDE_INT) (-1) << prec); | |
6d716ca8 RS |
201 | } |
202 | ||
e0f776fb RS |
203 | /* Unsigned types do not suffer sign extension or overflow. */ |
204 | if (TREE_UNSIGNED (TREE_TYPE (t))) | |
a7a05640 | 205 | return overflow; |
6d716ca8 | 206 | |
e0f776fb RS |
207 | /* If the value's sign bit is set, extend the sign. */ |
208 | if (prec != 2 * HOST_BITS_PER_WIDE_INT | |
906c4e36 RK |
209 | && (prec > HOST_BITS_PER_WIDE_INT |
210 | ? (TREE_INT_CST_HIGH (t) | |
211 | & ((HOST_WIDE_INT) 1 << (prec - HOST_BITS_PER_WIDE_INT - 1))) | |
212 | : TREE_INT_CST_LOW (t) & ((HOST_WIDE_INT) 1 << (prec - 1)))) | |
6d716ca8 RS |
213 | { |
214 | /* Value is negative: | |
215 | set to 1 all the bits that are outside this type's precision. */ | |
906c4e36 | 216 | if (prec > HOST_BITS_PER_WIDE_INT) |
6d716ca8 RS |
217 | { |
218 | TREE_INT_CST_HIGH (t) | |
906c4e36 | 219 | |= ((HOST_WIDE_INT) (-1) << (prec - HOST_BITS_PER_WIDE_INT)); |
6d716ca8 RS |
220 | } |
221 | else | |
222 | { | |
223 | TREE_INT_CST_HIGH (t) = -1; | |
906c4e36 RK |
224 | if (prec < HOST_BITS_PER_WIDE_INT) |
225 | TREE_INT_CST_LOW (t) |= ((HOST_WIDE_INT) (-1) << prec); | |
6d716ca8 RS |
226 | } |
227 | } | |
e0f776fb RS |
228 | |
229 | /* Yield nonzero if signed overflow occurred. */ | |
230 | return | |
231 | ((overflow | (low ^ TREE_INT_CST_LOW (t)) | (high ^ TREE_INT_CST_HIGH (t))) | |
232 | != 0); | |
6d716ca8 RS |
233 | } |
234 | \f | |
906c4e36 RK |
235 | /* Add two doubleword integers with doubleword result. |
236 | Each argument is given as two `HOST_WIDE_INT' pieces. | |
6d716ca8 | 237 | One argument is L1 and H1; the other, L2 and H2. |
37bdb7e3 | 238 | The value is stored as two `HOST_WIDE_INT' pieces in *LV and *HV. */ |
6d716ca8 | 239 | |
fe3e8e40 | 240 | int |
6d716ca8 | 241 | add_double (l1, h1, l2, h2, lv, hv) |
906c4e36 RK |
242 | HOST_WIDE_INT l1, h1, l2, h2; |
243 | HOST_WIDE_INT *lv, *hv; | |
6d716ca8 | 244 | { |
37bdb7e3 | 245 | HOST_WIDE_INT l, h; |
6d716ca8 | 246 | |
37bdb7e3 TG |
247 | l = l1 + l2; |
248 | h = h1 + h2 + ((unsigned HOST_WIDE_INT) l < l1); | |
6d716ca8 | 249 | |
37bdb7e3 TG |
250 | *lv = l; |
251 | *hv = h; | |
252 | return overflow_sum_sign (h1, h2, h); | |
6d716ca8 RS |
253 | } |
254 | ||
906c4e36 | 255 | /* Negate a doubleword integer with doubleword result. |
fe3e8e40 | 256 | Return nonzero if the operation overflows, assuming it's signed. |
906c4e36 | 257 | The argument is given as two `HOST_WIDE_INT' pieces in L1 and H1. |
37bdb7e3 | 258 | The value is stored as two `HOST_WIDE_INT' pieces in *LV and *HV. */ |
6d716ca8 | 259 | |
fe3e8e40 | 260 | int |
6d716ca8 | 261 | neg_double (l1, h1, lv, hv) |
906c4e36 RK |
262 | HOST_WIDE_INT l1, h1; |
263 | HOST_WIDE_INT *lv, *hv; | |
6d716ca8 RS |
264 | { |
265 | if (l1 == 0) | |
266 | { | |
267 | *lv = 0; | |
268 | *hv = - h1; | |
e0f776fb | 269 | return (*hv & h1) < 0; |
6d716ca8 RS |
270 | } |
271 | else | |
272 | { | |
273 | *lv = - l1; | |
274 | *hv = ~ h1; | |
fe3e8e40 | 275 | return 0; |
6d716ca8 RS |
276 | } |
277 | } | |
278 | \f | |
906c4e36 | 279 | /* Multiply two doubleword integers with doubleword result. |
fe3e8e40 | 280 | Return nonzero if the operation overflows, assuming it's signed. |
906c4e36 | 281 | Each argument is given as two `HOST_WIDE_INT' pieces. |
6d716ca8 | 282 | One argument is L1 and H1; the other, L2 and H2. |
37bdb7e3 | 283 | The value is stored as two `HOST_WIDE_INT' pieces in *LV and *HV. */ |
6d716ca8 | 284 | |
fe3e8e40 | 285 | int |
6d716ca8 | 286 | mul_double (l1, h1, l2, h2, lv, hv) |
906c4e36 RK |
287 | HOST_WIDE_INT l1, h1, l2, h2; |
288 | HOST_WIDE_INT *lv, *hv; | |
6d716ca8 | 289 | { |
37bdb7e3 TG |
290 | HOST_WIDE_INT arg1[4]; |
291 | HOST_WIDE_INT arg2[4]; | |
292 | HOST_WIDE_INT prod[4 * 2]; | |
293 | register unsigned HOST_WIDE_INT carry; | |
6d716ca8 | 294 | register int i, j, k; |
fe3e8e40 | 295 | HOST_WIDE_INT toplow, tophigh, neglow, neghigh; |
6d716ca8 | 296 | |
6d716ca8 RS |
297 | encode (arg1, l1, h1); |
298 | encode (arg2, l2, h2); | |
299 | ||
4c9a05bc | 300 | bzero ((char *) prod, sizeof prod); |
6d716ca8 | 301 | |
37bdb7e3 TG |
302 | for (i = 0; i < 4; i++) |
303 | { | |
304 | carry = 0; | |
305 | for (j = 0; j < 4; j++) | |
306 | { | |
307 | k = i + j; | |
308 | /* This product is <= 0xFFFE0001, the sum <= 0xFFFF0000. */ | |
309 | carry += arg1[i] * arg2[j]; | |
310 | /* Since prod[p] < 0xFFFF, this sum <= 0xFFFFFFFF. */ | |
311 | carry += prod[k]; | |
312 | prod[k] = LOWPART (carry); | |
313 | carry = HIGHPART (carry); | |
314 | } | |
315 | prod[i + 4] = carry; | |
316 | } | |
6d716ca8 | 317 | |
37bdb7e3 | 318 | decode (prod, lv, hv); /* This ignores prod[4] through prod[4*2-1] */ |
fe3e8e40 RS |
319 | |
320 | /* Check for overflow by calculating the top half of the answer in full; | |
321 | it should agree with the low half's sign bit. */ | |
37bdb7e3 | 322 | decode (prod+4, &toplow, &tophigh); |
fe3e8e40 RS |
323 | if (h1 < 0) |
324 | { | |
325 | neg_double (l2, h2, &neglow, &neghigh); | |
326 | add_double (neglow, neghigh, toplow, tophigh, &toplow, &tophigh); | |
327 | } | |
328 | if (h2 < 0) | |
329 | { | |
330 | neg_double (l1, h1, &neglow, &neghigh); | |
331 | add_double (neglow, neghigh, toplow, tophigh, &toplow, &tophigh); | |
332 | } | |
333 | return (*hv < 0 ? ~(toplow & tophigh) : toplow | tophigh) != 0; | |
6d716ca8 RS |
334 | } |
335 | \f | |
906c4e36 | 336 | /* Shift the doubleword integer in L1, H1 left by COUNT places |
6d716ca8 RS |
337 | keeping only PREC bits of result. |
338 | Shift right if COUNT is negative. | |
339 | ARITH nonzero specifies arithmetic shifting; otherwise use logical shift. | |
906c4e36 | 340 | Store the value as two `HOST_WIDE_INT' pieces in *LV and *HV. */ |
6d716ca8 | 341 | |
e0f776fb | 342 | void |
6d716ca8 | 343 | lshift_double (l1, h1, count, prec, lv, hv, arith) |
6dc7571d RK |
344 | HOST_WIDE_INT l1, h1, count; |
345 | int prec; | |
906c4e36 | 346 | HOST_WIDE_INT *lv, *hv; |
6d716ca8 RS |
347 | int arith; |
348 | { | |
6d716ca8 RS |
349 | if (count < 0) |
350 | { | |
351 | rshift_double (l1, h1, - count, prec, lv, hv, arith); | |
e0f776fb | 352 | return; |
6d716ca8 | 353 | } |
37bdb7e3 | 354 | |
3d1877b1 RK |
355 | #ifdef SHIFT_COUNT_TRUNCATED |
356 | if (SHIFT_COUNT_TRUNCATED) | |
357 | count %= prec; | |
358 | #endif | |
6d716ca8 | 359 | |
37bdb7e3 | 360 | if (count >= HOST_BITS_PER_WIDE_INT) |
6d716ca8 | 361 | { |
2fde567e | 362 | *hv = (unsigned HOST_WIDE_INT) l1 << (count - HOST_BITS_PER_WIDE_INT); |
37bdb7e3 TG |
363 | *lv = 0; |
364 | } | |
365 | else | |
366 | { | |
367 | *hv = (((unsigned HOST_WIDE_INT) h1 << count) | |
2fde567e | 368 | | ((unsigned HOST_WIDE_INT) l1 >> (HOST_BITS_PER_WIDE_INT - count - 1) >> 1)); |
37bdb7e3 | 369 | *lv = (unsigned HOST_WIDE_INT) l1 << count; |
6d716ca8 | 370 | } |
6d716ca8 RS |
371 | } |
372 | ||
906c4e36 | 373 | /* Shift the doubleword integer in L1, H1 right by COUNT places |
6d716ca8 RS |
374 | keeping only PREC bits of result. COUNT must be positive. |
375 | ARITH nonzero specifies arithmetic shifting; otherwise use logical shift. | |
906c4e36 | 376 | Store the value as two `HOST_WIDE_INT' pieces in *LV and *HV. */ |
6d716ca8 RS |
377 | |
378 | void | |
379 | rshift_double (l1, h1, count, prec, lv, hv, arith) | |
6dc7571d RK |
380 | HOST_WIDE_INT l1, h1, count; |
381 | int prec; | |
906c4e36 | 382 | HOST_WIDE_INT *lv, *hv; |
6d716ca8 RS |
383 | int arith; |
384 | { | |
37bdb7e3 TG |
385 | unsigned HOST_WIDE_INT signmask; |
386 | signmask = (arith | |
387 | ? -((unsigned HOST_WIDE_INT) h1 >> (HOST_BITS_PER_WIDE_INT - 1)) | |
388 | : 0); | |
6d716ca8 | 389 | |
3d1877b1 RK |
390 | #ifdef SHIFT_COUNT_TRUNCATED |
391 | if (SHIFT_COUNT_TRUNCATED) | |
392 | count %= prec; | |
393 | #endif | |
6d716ca8 | 394 | |
37bdb7e3 | 395 | if (count >= HOST_BITS_PER_WIDE_INT) |
6d716ca8 | 396 | { |
37bdb7e3 | 397 | *hv = signmask; |
2fde567e KG |
398 | *lv = ((signmask << (2 * HOST_BITS_PER_WIDE_INT - count - 1) << 1) |
399 | | ((unsigned HOST_WIDE_INT) h1 >> (count - HOST_BITS_PER_WIDE_INT))); | |
37bdb7e3 TG |
400 | } |
401 | else | |
402 | { | |
403 | *lv = (((unsigned HOST_WIDE_INT) l1 >> count) | |
2fde567e KG |
404 | | ((unsigned HOST_WIDE_INT) h1 << (HOST_BITS_PER_WIDE_INT - count - 1) << 1)); |
405 | *hv = ((signmask << (HOST_BITS_PER_WIDE_INT - count)) | |
37bdb7e3 | 406 | | ((unsigned HOST_WIDE_INT) h1 >> count)); |
6d716ca8 | 407 | } |
6d716ca8 RS |
408 | } |
409 | \f | |
37bdb7e3 | 410 | /* Rotate the doubleword integer in L1, H1 left by COUNT places |
6d716ca8 RS |
411 | keeping only PREC bits of result. |
412 | Rotate right if COUNT is negative. | |
906c4e36 | 413 | Store the value as two `HOST_WIDE_INT' pieces in *LV and *HV. */ |
6d716ca8 RS |
414 | |
415 | void | |
416 | lrotate_double (l1, h1, count, prec, lv, hv) | |
6dc7571d RK |
417 | HOST_WIDE_INT l1, h1, count; |
418 | int prec; | |
906c4e36 | 419 | HOST_WIDE_INT *lv, *hv; |
6d716ca8 | 420 | { |
4d39710e | 421 | HOST_WIDE_INT s1l, s1h, s2l, s2h; |
6d716ca8 | 422 | |
4d39710e | 423 | count %= prec; |
6d716ca8 | 424 | if (count < 0) |
4d39710e | 425 | count += prec; |
6d716ca8 | 426 | |
4d39710e RK |
427 | lshift_double (l1, h1, count, prec, &s1l, &s1h, 0); |
428 | rshift_double (l1, h1, prec - count, prec, &s2l, &s2h, 0); | |
429 | *lv = s1l | s2l; | |
430 | *hv = s1h | s2h; | |
6d716ca8 RS |
431 | } |
432 | ||
906c4e36 | 433 | /* Rotate the doubleword integer in L1, H1 left by COUNT places |
6d716ca8 | 434 | keeping only PREC bits of result. COUNT must be positive. |
906c4e36 | 435 | Store the value as two `HOST_WIDE_INT' pieces in *LV and *HV. */ |
6d716ca8 RS |
436 | |
437 | void | |
438 | rrotate_double (l1, h1, count, prec, lv, hv) | |
6dc7571d RK |
439 | HOST_WIDE_INT l1, h1, count; |
440 | int prec; | |
906c4e36 | 441 | HOST_WIDE_INT *lv, *hv; |
6d716ca8 | 442 | { |
4d39710e | 443 | HOST_WIDE_INT s1l, s1h, s2l, s2h; |
6d716ca8 | 444 | |
4d39710e RK |
445 | count %= prec; |
446 | if (count < 0) | |
447 | count += prec; | |
6d716ca8 | 448 | |
4d39710e RK |
449 | rshift_double (l1, h1, count, prec, &s1l, &s1h, 0); |
450 | lshift_double (l1, h1, prec - count, prec, &s2l, &s2h, 0); | |
451 | *lv = s1l | s2l; | |
452 | *hv = s1h | s2h; | |
6d716ca8 RS |
453 | } |
454 | \f | |
906c4e36 | 455 | /* Divide doubleword integer LNUM, HNUM by doubleword integer LDEN, HDEN |
6d716ca8 RS |
456 | for a quotient (stored in *LQUO, *HQUO) and remainder (in *LREM, *HREM). |
457 | CODE is a tree code for a kind of division, one of | |
458 | TRUNC_DIV_EXPR, FLOOR_DIV_EXPR, CEIL_DIV_EXPR, ROUND_DIV_EXPR | |
459 | or EXACT_DIV_EXPR | |
fe3e8e40 RS |
460 | It controls how the quotient is rounded to a integer. |
461 | Return nonzero if the operation overflows. | |
6d716ca8 RS |
462 | UNS nonzero says do unsigned division. */ |
463 | ||
dbb5b3ce | 464 | int |
6d716ca8 RS |
465 | div_and_round_double (code, uns, |
466 | lnum_orig, hnum_orig, lden_orig, hden_orig, | |
467 | lquo, hquo, lrem, hrem) | |
468 | enum tree_code code; | |
469 | int uns; | |
906c4e36 RK |
470 | HOST_WIDE_INT lnum_orig, hnum_orig; /* num == numerator == dividend */ |
471 | HOST_WIDE_INT lden_orig, hden_orig; /* den == denominator == divisor */ | |
472 | HOST_WIDE_INT *lquo, *hquo, *lrem, *hrem; | |
6d716ca8 RS |
473 | { |
474 | int quo_neg = 0; | |
37bdb7e3 TG |
475 | HOST_WIDE_INT num[4 + 1]; /* extra element for scaling. */ |
476 | HOST_WIDE_INT den[4], quo[4]; | |
477 | register int i, j; | |
478 | unsigned HOST_WIDE_INT work; | |
10fa1ee2 | 479 | register unsigned HOST_WIDE_INT carry = 0; |
88ee2651 | 480 | HOST_WIDE_INT lnum = lnum_orig; |
b8eb43a2 | 481 | HOST_WIDE_INT hnum = hnum_orig; |
88ee2651 | 482 | HOST_WIDE_INT lden = lden_orig; |
b8eb43a2 | 483 | HOST_WIDE_INT hden = hden_orig; |
fe3e8e40 | 484 | int overflow = 0; |
6d716ca8 RS |
485 | |
486 | if ((hden == 0) && (lden == 0)) | |
956d6950 | 487 | overflow = 1, lden = 1; |
6d716ca8 RS |
488 | |
489 | /* calculate quotient sign and convert operands to unsigned. */ | |
490 | if (!uns) | |
491 | { | |
fe3e8e40 | 492 | if (hnum < 0) |
6d716ca8 RS |
493 | { |
494 | quo_neg = ~ quo_neg; | |
fe3e8e40 RS |
495 | /* (minimum integer) / (-1) is the only overflow case. */ |
496 | if (neg_double (lnum, hnum, &lnum, &hnum) && (lden & hden) == -1) | |
497 | overflow = 1; | |
6d716ca8 | 498 | } |
fe3e8e40 | 499 | if (hden < 0) |
6d716ca8 RS |
500 | { |
501 | quo_neg = ~ quo_neg; | |
fe3e8e40 | 502 | neg_double (lden, hden, &lden, &hden); |
6d716ca8 RS |
503 | } |
504 | } | |
505 | ||
506 | if (hnum == 0 && hden == 0) | |
507 | { /* single precision */ | |
508 | *hquo = *hrem = 0; | |
88ee2651 RK |
509 | /* This unsigned division rounds toward zero. */ |
510 | *lquo = lnum / (unsigned HOST_WIDE_INT) lden; | |
6d716ca8 RS |
511 | goto finish_up; |
512 | } | |
513 | ||
514 | if (hnum == 0) | |
515 | { /* trivial case: dividend < divisor */ | |
516 | /* hden != 0 already checked. */ | |
517 | *hquo = *lquo = 0; | |
518 | *hrem = hnum; | |
519 | *lrem = lnum; | |
520 | goto finish_up; | |
521 | } | |
522 | ||
4c9a05bc | 523 | bzero ((char *) quo, sizeof quo); |
6d716ca8 | 524 | |
4c9a05bc RK |
525 | bzero ((char *) num, sizeof num); /* to zero 9th element */ |
526 | bzero ((char *) den, sizeof den); | |
6d716ca8 RS |
527 | |
528 | encode (num, lnum, hnum); | |
529 | encode (den, lden, hden); | |
530 | ||
37bdb7e3 TG |
531 | /* Special code for when the divisor < BASE. */ |
532 | if (hden == 0 && lden < BASE) | |
533 | { | |
6d716ca8 | 534 | /* hnum != 0 already checked. */ |
37bdb7e3 | 535 | for (i = 4 - 1; i >= 0; i--) |
6d716ca8 | 536 | { |
37bdb7e3 | 537 | work = num[i] + carry * BASE; |
88ee2651 RK |
538 | quo[i] = work / (unsigned HOST_WIDE_INT) lden; |
539 | carry = work % (unsigned HOST_WIDE_INT) lden; | |
6d716ca8 RS |
540 | } |
541 | } | |
37bdb7e3 TG |
542 | else |
543 | { | |
544 | /* Full double precision division, | |
545 | with thanks to Don Knuth's "Seminumerical Algorithms". */ | |
10fa1ee2 RK |
546 | int num_hi_sig, den_hi_sig; |
547 | unsigned HOST_WIDE_INT quo_est, scale; | |
6d716ca8 RS |
548 | |
549 | /* Find the highest non-zero divisor digit. */ | |
37bdb7e3 | 550 | for (i = 4 - 1; ; i--) |
6d716ca8 RS |
551 | if (den[i] != 0) { |
552 | den_hi_sig = i; | |
553 | break; | |
554 | } | |
6d716ca8 RS |
555 | |
556 | /* Insure that the first digit of the divisor is at least BASE/2. | |
557 | This is required by the quotient digit estimation algorithm. */ | |
558 | ||
559 | scale = BASE / (den[den_hi_sig] + 1); | |
560 | if (scale > 1) { /* scale divisor and dividend */ | |
561 | carry = 0; | |
37bdb7e3 | 562 | for (i = 0; i <= 4 - 1; i++) { |
6d716ca8 | 563 | work = (num[i] * scale) + carry; |
37bdb7e3 TG |
564 | num[i] = LOWPART (work); |
565 | carry = HIGHPART (work); | |
566 | } num[4] = carry; | |
6d716ca8 | 567 | carry = 0; |
37bdb7e3 | 568 | for (i = 0; i <= 4 - 1; i++) { |
6d716ca8 | 569 | work = (den[i] * scale) + carry; |
37bdb7e3 TG |
570 | den[i] = LOWPART (work); |
571 | carry = HIGHPART (work); | |
6d716ca8 RS |
572 | if (den[i] != 0) den_hi_sig = i; |
573 | } | |
574 | } | |
575 | ||
37bdb7e3 TG |
576 | num_hi_sig = 4; |
577 | ||
6d716ca8 | 578 | /* Main loop */ |
37bdb7e3 | 579 | for (i = num_hi_sig - den_hi_sig - 1; i >= 0; i--) { |
6dc42e49 | 580 | /* guess the next quotient digit, quo_est, by dividing the first |
6d716ca8 RS |
581 | two remaining dividend digits by the high order quotient digit. |
582 | quo_est is never low and is at most 2 high. */ | |
37bdb7e3 | 583 | unsigned HOST_WIDE_INT tmp; |
6d716ca8 | 584 | |
37bdb7e3 TG |
585 | num_hi_sig = i + den_hi_sig + 1; |
586 | work = num[num_hi_sig] * BASE + num[num_hi_sig - 1]; | |
587 | if (num[num_hi_sig] != den[den_hi_sig]) | |
6d716ca8 | 588 | quo_est = work / den[den_hi_sig]; |
37bdb7e3 | 589 | else |
6d716ca8 | 590 | quo_est = BASE - 1; |
6d716ca8 RS |
591 | |
592 | /* refine quo_est so it's usually correct, and at most one high. */ | |
37bdb7e3 TG |
593 | tmp = work - quo_est * den[den_hi_sig]; |
594 | if (tmp < BASE | |
595 | && den[den_hi_sig - 1] * quo_est > (tmp * BASE + num[num_hi_sig - 2])) | |
6d716ca8 RS |
596 | quo_est--; |
597 | ||
598 | /* Try QUO_EST as the quotient digit, by multiplying the | |
599 | divisor by QUO_EST and subtracting from the remaining dividend. | |
600 | Keep in mind that QUO_EST is the I - 1st digit. */ | |
601 | ||
602 | carry = 0; | |
6d716ca8 RS |
603 | for (j = 0; j <= den_hi_sig; j++) |
604 | { | |
37bdb7e3 TG |
605 | work = quo_est * den[j] + carry; |
606 | carry = HIGHPART (work); | |
607 | work = num[i + j] - LOWPART (work); | |
608 | num[i + j] = LOWPART (work); | |
609 | carry += HIGHPART (work) != 0; | |
6d716ca8 RS |
610 | } |
611 | ||
612 | /* if quo_est was high by one, then num[i] went negative and | |
613 | we need to correct things. */ | |
614 | ||
37bdb7e3 | 615 | if (num[num_hi_sig] < carry) |
6d716ca8 RS |
616 | { |
617 | quo_est--; | |
618 | carry = 0; /* add divisor back in */ | |
619 | for (j = 0; j <= den_hi_sig; j++) | |
620 | { | |
37bdb7e3 TG |
621 | work = num[i + j] + den[j] + carry; |
622 | carry = HIGHPART (work); | |
623 | num[i + j] = LOWPART (work); | |
6d716ca8 | 624 | } |
37bdb7e3 | 625 | num [num_hi_sig] += carry; |
6d716ca8 RS |
626 | } |
627 | ||
628 | /* store the quotient digit. */ | |
37bdb7e3 | 629 | quo[i] = quo_est; |
6d716ca8 RS |
630 | } |
631 | } | |
632 | ||
633 | decode (quo, lquo, hquo); | |
634 | ||
635 | finish_up: | |
636 | /* if result is negative, make it so. */ | |
637 | if (quo_neg) | |
638 | neg_double (*lquo, *hquo, lquo, hquo); | |
639 | ||
640 | /* compute trial remainder: rem = num - (quo * den) */ | |
641 | mul_double (*lquo, *hquo, lden_orig, hden_orig, lrem, hrem); | |
642 | neg_double (*lrem, *hrem, lrem, hrem); | |
643 | add_double (lnum_orig, hnum_orig, *lrem, *hrem, lrem, hrem); | |
644 | ||
645 | switch (code) | |
646 | { | |
647 | case TRUNC_DIV_EXPR: | |
648 | case TRUNC_MOD_EXPR: /* round toward zero */ | |
649 | case EXACT_DIV_EXPR: /* for this one, it shouldn't matter */ | |
fe3e8e40 | 650 | return overflow; |
6d716ca8 RS |
651 | |
652 | case FLOOR_DIV_EXPR: | |
653 | case FLOOR_MOD_EXPR: /* round toward negative infinity */ | |
654 | if (quo_neg && (*lrem != 0 || *hrem != 0)) /* ratio < 0 && rem != 0 */ | |
655 | { | |
656 | /* quo = quo - 1; */ | |
906c4e36 RK |
657 | add_double (*lquo, *hquo, (HOST_WIDE_INT) -1, (HOST_WIDE_INT) -1, |
658 | lquo, hquo); | |
6d716ca8 | 659 | } |
fe3e8e40 | 660 | else return overflow; |
6d716ca8 RS |
661 | break; |
662 | ||
663 | case CEIL_DIV_EXPR: | |
664 | case CEIL_MOD_EXPR: /* round toward positive infinity */ | |
665 | if (!quo_neg && (*lrem != 0 || *hrem != 0)) /* ratio > 0 && rem != 0 */ | |
666 | { | |
906c4e36 RK |
667 | add_double (*lquo, *hquo, (HOST_WIDE_INT) 1, (HOST_WIDE_INT) 0, |
668 | lquo, hquo); | |
6d716ca8 | 669 | } |
fe3e8e40 | 670 | else return overflow; |
6d716ca8 RS |
671 | break; |
672 | ||
673 | case ROUND_DIV_EXPR: | |
674 | case ROUND_MOD_EXPR: /* round to closest integer */ | |
675 | { | |
906c4e36 RK |
676 | HOST_WIDE_INT labs_rem = *lrem, habs_rem = *hrem; |
677 | HOST_WIDE_INT labs_den = lden, habs_den = hden, ltwice, htwice; | |
6d716ca8 RS |
678 | |
679 | /* get absolute values */ | |
680 | if (*hrem < 0) neg_double (*lrem, *hrem, &labs_rem, &habs_rem); | |
681 | if (hden < 0) neg_double (lden, hden, &labs_den, &habs_den); | |
682 | ||
683 | /* if (2 * abs (lrem) >= abs (lden)) */ | |
906c4e36 RK |
684 | mul_double ((HOST_WIDE_INT) 2, (HOST_WIDE_INT) 0, |
685 | labs_rem, habs_rem, <wice, &htwice); | |
686 | if (((unsigned HOST_WIDE_INT) habs_den | |
687 | < (unsigned HOST_WIDE_INT) htwice) | |
688 | || (((unsigned HOST_WIDE_INT) habs_den | |
689 | == (unsigned HOST_WIDE_INT) htwice) | |
690 | && ((HOST_WIDE_INT unsigned) labs_den | |
691 | < (unsigned HOST_WIDE_INT) ltwice))) | |
6d716ca8 RS |
692 | { |
693 | if (*hquo < 0) | |
694 | /* quo = quo - 1; */ | |
906c4e36 RK |
695 | add_double (*lquo, *hquo, |
696 | (HOST_WIDE_INT) -1, (HOST_WIDE_INT) -1, lquo, hquo); | |
6d716ca8 RS |
697 | else |
698 | /* quo = quo + 1; */ | |
906c4e36 RK |
699 | add_double (*lquo, *hquo, (HOST_WIDE_INT) 1, (HOST_WIDE_INT) 0, |
700 | lquo, hquo); | |
6d716ca8 | 701 | } |
fe3e8e40 | 702 | else return overflow; |
6d716ca8 RS |
703 | } |
704 | break; | |
705 | ||
706 | default: | |
707 | abort (); | |
708 | } | |
709 | ||
710 | /* compute true remainder: rem = num - (quo * den) */ | |
711 | mul_double (*lquo, *hquo, lden_orig, hden_orig, lrem, hrem); | |
712 | neg_double (*lrem, *hrem, lrem, hrem); | |
713 | add_double (lnum_orig, hnum_orig, *lrem, *hrem, lrem, hrem); | |
fe3e8e40 | 714 | return overflow; |
6d716ca8 RS |
715 | } |
716 | \f | |
5008b8ae | 717 | #ifndef REAL_ARITHMETIC |
649ff3b4 RK |
718 | /* Effectively truncate a real value to represent the nearest possible value |
719 | in a narrower mode. The result is actually represented in the same data | |
720 | type as the argument, but its value is usually different. | |
721 | ||
722 | A trap may occur during the FP operations and it is the responsibility | |
723 | of the calling function to have a handler established. */ | |
5352b11a RS |
724 | |
725 | REAL_VALUE_TYPE | |
726 | real_value_truncate (mode, arg) | |
727 | enum machine_mode mode; | |
728 | REAL_VALUE_TYPE arg; | |
729 | { | |
649ff3b4 | 730 | return REAL_VALUE_TRUNCATE (mode, arg); |
5352b11a RS |
731 | } |
732 | ||
6d716ca8 RS |
733 | #if TARGET_FLOAT_FORMAT == IEEE_FLOAT_FORMAT |
734 | ||
735 | /* Check for infinity in an IEEE double precision number. */ | |
736 | ||
737 | int | |
738 | target_isinf (x) | |
739 | REAL_VALUE_TYPE x; | |
740 | { | |
741 | /* The IEEE 64-bit double format. */ | |
742 | union { | |
743 | REAL_VALUE_TYPE d; | |
744 | struct { | |
745 | unsigned sign : 1; | |
746 | unsigned exponent : 11; | |
747 | unsigned mantissa1 : 20; | |
748 | unsigned mantissa2; | |
749 | } little_endian; | |
750 | struct { | |
751 | unsigned mantissa2; | |
752 | unsigned mantissa1 : 20; | |
753 | unsigned exponent : 11; | |
754 | unsigned sign : 1; | |
755 | } big_endian; | |
756 | } u; | |
757 | ||
758 | u.d = dconstm1; | |
759 | if (u.big_endian.sign == 1) | |
760 | { | |
761 | u.d = x; | |
762 | return (u.big_endian.exponent == 2047 | |
763 | && u.big_endian.mantissa1 == 0 | |
764 | && u.big_endian.mantissa2 == 0); | |
765 | } | |
766 | else | |
767 | { | |
768 | u.d = x; | |
769 | return (u.little_endian.exponent == 2047 | |
770 | && u.little_endian.mantissa1 == 0 | |
771 | && u.little_endian.mantissa2 == 0); | |
772 | } | |
773 | } | |
774 | ||
7d4d4d22 RS |
775 | /* Check whether an IEEE double precision number is a NaN. */ |
776 | ||
777 | int | |
778 | target_isnan (x) | |
779 | REAL_VALUE_TYPE x; | |
780 | { | |
781 | /* The IEEE 64-bit double format. */ | |
782 | union { | |
783 | REAL_VALUE_TYPE d; | |
784 | struct { | |
785 | unsigned sign : 1; | |
786 | unsigned exponent : 11; | |
787 | unsigned mantissa1 : 20; | |
788 | unsigned mantissa2; | |
789 | } little_endian; | |
790 | struct { | |
791 | unsigned mantissa2; | |
792 | unsigned mantissa1 : 20; | |
793 | unsigned exponent : 11; | |
794 | unsigned sign : 1; | |
795 | } big_endian; | |
796 | } u; | |
797 | ||
798 | u.d = dconstm1; | |
799 | if (u.big_endian.sign == 1) | |
800 | { | |
801 | u.d = x; | |
802 | return (u.big_endian.exponent == 2047 | |
803 | && (u.big_endian.mantissa1 != 0 | |
804 | || u.big_endian.mantissa2 != 0)); | |
805 | } | |
806 | else | |
807 | { | |
808 | u.d = x; | |
809 | return (u.little_endian.exponent == 2047 | |
810 | && (u.little_endian.mantissa1 != 0 | |
811 | || u.little_endian.mantissa2 != 0)); | |
812 | } | |
813 | } | |
814 | ||
c05a9b68 | 815 | /* Check for a negative IEEE double precision number. */ |
6d716ca8 RS |
816 | |
817 | int | |
c05a9b68 | 818 | target_negative (x) |
6d716ca8 RS |
819 | REAL_VALUE_TYPE x; |
820 | { | |
c05a9b68 RS |
821 | /* The IEEE 64-bit double format. */ |
822 | union { | |
823 | REAL_VALUE_TYPE d; | |
824 | struct { | |
825 | unsigned sign : 1; | |
826 | unsigned exponent : 11; | |
827 | unsigned mantissa1 : 20; | |
828 | unsigned mantissa2; | |
829 | } little_endian; | |
830 | struct { | |
831 | unsigned mantissa2; | |
832 | unsigned mantissa1 : 20; | |
833 | unsigned exponent : 11; | |
834 | unsigned sign : 1; | |
835 | } big_endian; | |
836 | } u; | |
6d716ca8 | 837 | |
c05a9b68 RS |
838 | u.d = dconstm1; |
839 | if (u.big_endian.sign == 1) | |
840 | { | |
841 | u.d = x; | |
842 | return u.big_endian.sign; | |
843 | } | |
844 | else | |
845 | { | |
846 | u.d = x; | |
847 | return u.little_endian.sign; | |
848 | } | |
6d716ca8 RS |
849 | } |
850 | #else /* Target not IEEE */ | |
851 | ||
852 | /* Let's assume other float formats don't have infinity. | |
853 | (This can be overridden by redefining REAL_VALUE_ISINF.) */ | |
854 | ||
855 | target_isinf (x) | |
856 | REAL_VALUE_TYPE x; | |
857 | { | |
858 | return 0; | |
859 | } | |
860 | ||
7d4d4d22 RS |
861 | /* Let's assume other float formats don't have NaNs. |
862 | (This can be overridden by redefining REAL_VALUE_ISNAN.) */ | |
863 | ||
864 | target_isnan (x) | |
865 | REAL_VALUE_TYPE x; | |
866 | { | |
867 | return 0; | |
868 | } | |
869 | ||
6d716ca8 | 870 | /* Let's assume other float formats don't have minus zero. |
c05a9b68 | 871 | (This can be overridden by redefining REAL_VALUE_NEGATIVE.) */ |
6d716ca8 | 872 | |
c05a9b68 | 873 | target_negative (x) |
6d716ca8 RS |
874 | REAL_VALUE_TYPE x; |
875 | { | |
c05a9b68 | 876 | return x < 0; |
6d716ca8 RS |
877 | } |
878 | #endif /* Target not IEEE */ | |
39647dcb RK |
879 | |
880 | /* Try to change R into its exact multiplicative inverse in machine mode | |
881 | MODE. Return nonzero function value if successful. */ | |
882 | ||
883 | int | |
884 | exact_real_inverse (mode, r) | |
885 | enum machine_mode mode; | |
886 | REAL_VALUE_TYPE *r; | |
887 | { | |
888 | union | |
889 | { | |
890 | double d; | |
891 | unsigned short i[4]; | |
892 | }x, t, y; | |
893 | int i; | |
894 | ||
895 | /* Usually disable if bounds checks are not reliable. */ | |
896 | if ((HOST_FLOAT_FORMAT != TARGET_FLOAT_FORMAT) && !flag_pretend_float) | |
897 | return 0; | |
898 | ||
899 | /* Set array index to the less significant bits in the unions, depending | |
900 | on the endian-ness of the host doubles. | |
901 | Disable if insufficient information on the data structure. */ | |
902 | #if HOST_FLOAT_FORMAT == UNKNOWN_FLOAT_FORMAT | |
903 | return 0; | |
904 | #else | |
905 | #if HOST_FLOAT_FORMAT == VAX_FLOAT_FORMAT | |
906 | #define K 2 | |
907 | #else | |
908 | #if HOST_FLOAT_FORMAT == IBM_FLOAT_FORMAT | |
909 | #define K 2 | |
910 | #else | |
911 | #define K (2 * HOST_FLOAT_WORDS_BIG_ENDIAN) | |
912 | #endif | |
913 | #endif | |
914 | #endif | |
915 | ||
916 | if (setjmp (float_error)) | |
917 | { | |
918 | /* Don't do the optimization if there was an arithmetic error. */ | |
919 | fail: | |
920 | set_float_handler (NULL_PTR); | |
921 | return 0; | |
922 | } | |
923 | set_float_handler (float_error); | |
924 | ||
925 | /* Domain check the argument. */ | |
926 | x.d = *r; | |
927 | if (x.d == 0.0) | |
928 | goto fail; | |
929 | ||
930 | #ifdef REAL_INFINITY | |
931 | if (REAL_VALUE_ISINF (x.d) || REAL_VALUE_ISNAN (x.d)) | |
932 | goto fail; | |
933 | #endif | |
934 | ||
935 | /* Compute the reciprocal and check for numerical exactness. | |
936 | It is unnecessary to check all the significand bits to determine | |
937 | whether X is a power of 2. If X is not, then it is impossible for | |
938 | the bottom half significand of both X and 1/X to be all zero bits. | |
939 | Hence we ignore the data structure of the top half and examine only | |
940 | the low order bits of the two significands. */ | |
941 | t.d = 1.0 / x.d; | |
942 | if (x.i[K] != 0 || x.i[K + 1] != 0 || t.i[K] != 0 || t.i[K + 1] != 0) | |
943 | goto fail; | |
944 | ||
945 | /* Truncate to the required mode and range-check the result. */ | |
946 | y.d = REAL_VALUE_TRUNCATE (mode, t.d); | |
947 | #ifdef CHECK_FLOAT_VALUE | |
948 | i = 0; | |
949 | if (CHECK_FLOAT_VALUE (mode, y.d, i)) | |
950 | goto fail; | |
951 | #endif | |
952 | ||
953 | /* Fail if truncation changed the value. */ | |
954 | if (y.d != t.d || y.d == 0.0) | |
955 | goto fail; | |
956 | ||
957 | #ifdef REAL_INFINITY | |
958 | if (REAL_VALUE_ISINF (y.d) || REAL_VALUE_ISNAN (y.d)) | |
959 | goto fail; | |
960 | #endif | |
961 | ||
962 | /* Output the reciprocal and return success flag. */ | |
963 | set_float_handler (NULL_PTR); | |
964 | *r = y.d; | |
965 | return 1; | |
966 | } | |
5008b8ae | 967 | #endif /* no REAL_ARITHMETIC */ |
6d716ca8 RS |
968 | \f |
969 | /* Split a tree IN into a constant and a variable part | |
970 | that could be combined with CODE to make IN. | |
971 | CODE must be a commutative arithmetic operation. | |
972 | Store the constant part into *CONP and the variable in &VARP. | |
973 | Return 1 if this was done; zero means the tree IN did not decompose | |
974 | this way. | |
975 | ||
976 | If CODE is PLUS_EXPR we also split trees that use MINUS_EXPR. | |
977 | Therefore, we must tell the caller whether the variable part | |
978 | was subtracted. We do this by storing 1 or -1 into *VARSIGNP. | |
979 | The value stored is the coefficient for the variable term. | |
980 | The constant term we return should always be added; | |
981 | we negate it if necessary. */ | |
982 | ||
983 | static int | |
984 | split_tree (in, code, varp, conp, varsignp) | |
985 | tree in; | |
986 | enum tree_code code; | |
987 | tree *varp, *conp; | |
988 | int *varsignp; | |
989 | { | |
990 | register tree outtype = TREE_TYPE (in); | |
991 | *varp = 0; | |
992 | *conp = 0; | |
993 | ||
994 | /* Strip any conversions that don't change the machine mode. */ | |
995 | while ((TREE_CODE (in) == NOP_EXPR | |
996 | || TREE_CODE (in) == CONVERT_EXPR) | |
997 | && (TYPE_MODE (TREE_TYPE (in)) | |
998 | == TYPE_MODE (TREE_TYPE (TREE_OPERAND (in, 0))))) | |
999 | in = TREE_OPERAND (in, 0); | |
1000 | ||
1001 | if (TREE_CODE (in) == code | |
7178e3af | 1002 | || (! FLOAT_TYPE_P (TREE_TYPE (in)) |
6d716ca8 RS |
1003 | /* We can associate addition and subtraction together |
1004 | (even though the C standard doesn't say so) | |
1005 | for integers because the value is not affected. | |
1006 | For reals, the value might be affected, so we can't. */ | |
7178e3af RK |
1007 | && ((code == PLUS_EXPR && TREE_CODE (in) == MINUS_EXPR) |
1008 | || (code == MINUS_EXPR && TREE_CODE (in) == PLUS_EXPR)))) | |
6d716ca8 RS |
1009 | { |
1010 | enum tree_code code = TREE_CODE (TREE_OPERAND (in, 0)); | |
1011 | if (code == INTEGER_CST) | |
1012 | { | |
1013 | *conp = TREE_OPERAND (in, 0); | |
1014 | *varp = TREE_OPERAND (in, 1); | |
1015 | if (TYPE_MODE (TREE_TYPE (*varp)) != TYPE_MODE (outtype) | |
1016 | && TREE_TYPE (*varp) != outtype) | |
1017 | *varp = convert (outtype, *varp); | |
1018 | *varsignp = (TREE_CODE (in) == MINUS_EXPR) ? -1 : 1; | |
1019 | return 1; | |
1020 | } | |
1021 | if (TREE_CONSTANT (TREE_OPERAND (in, 1))) | |
1022 | { | |
1023 | *conp = TREE_OPERAND (in, 1); | |
1024 | *varp = TREE_OPERAND (in, 0); | |
1025 | *varsignp = 1; | |
1026 | if (TYPE_MODE (TREE_TYPE (*varp)) != TYPE_MODE (outtype) | |
1027 | && TREE_TYPE (*varp) != outtype) | |
1028 | *varp = convert (outtype, *varp); | |
1029 | if (TREE_CODE (in) == MINUS_EXPR) | |
1030 | { | |
1031 | /* If operation is subtraction and constant is second, | |
1032 | must negate it to get an additive constant. | |
1033 | And this cannot be done unless it is a manifest constant. | |
1034 | It could also be the address of a static variable. | |
1035 | We cannot negate that, so give up. */ | |
1036 | if (TREE_CODE (*conp) == INTEGER_CST) | |
1037 | /* Subtracting from integer_zero_node loses for long long. */ | |
1038 | *conp = fold (build1 (NEGATE_EXPR, TREE_TYPE (*conp), *conp)); | |
1039 | else | |
1040 | return 0; | |
1041 | } | |
1042 | return 1; | |
1043 | } | |
1044 | if (TREE_CONSTANT (TREE_OPERAND (in, 0))) | |
1045 | { | |
1046 | *conp = TREE_OPERAND (in, 0); | |
1047 | *varp = TREE_OPERAND (in, 1); | |
1048 | if (TYPE_MODE (TREE_TYPE (*varp)) != TYPE_MODE (outtype) | |
1049 | && TREE_TYPE (*varp) != outtype) | |
1050 | *varp = convert (outtype, *varp); | |
1051 | *varsignp = (TREE_CODE (in) == MINUS_EXPR) ? -1 : 1; | |
1052 | return 1; | |
1053 | } | |
1054 | } | |
1055 | return 0; | |
1056 | } | |
1057 | \f | |
e9a25f70 | 1058 | /* Combine two integer constants ARG1 and ARG2 under operation CODE |
6d716ca8 | 1059 | to produce a new constant. |
91d33e36 | 1060 | |
e9a25f70 JL |
1061 | If NOTRUNC is nonzero, do not truncate the result to fit the data type. |
1062 | If FORSIZE is nonzero, compute overflow for unsigned types. */ | |
6d716ca8 | 1063 | |
6d716ca8 | 1064 | static tree |
e9a25f70 | 1065 | int_const_binop (code, arg1, arg2, notrunc, forsize) |
6d716ca8 RS |
1066 | enum tree_code code; |
1067 | register tree arg1, arg2; | |
e9a25f70 | 1068 | int notrunc, forsize; |
6d716ca8 | 1069 | { |
e9a25f70 JL |
1070 | HOST_WIDE_INT int1l, int1h, int2l, int2h; |
1071 | HOST_WIDE_INT low, hi; | |
1072 | HOST_WIDE_INT garbagel, garbageh; | |
1073 | register tree t; | |
1074 | int uns = TREE_UNSIGNED (TREE_TYPE (arg1)); | |
1075 | int overflow = 0; | |
1076 | int no_overflow = 0; | |
3dedc65a | 1077 | |
e9a25f70 JL |
1078 | int1l = TREE_INT_CST_LOW (arg1); |
1079 | int1h = TREE_INT_CST_HIGH (arg1); | |
1080 | int2l = TREE_INT_CST_LOW (arg2); | |
1081 | int2h = TREE_INT_CST_HIGH (arg2); | |
1082 | ||
1083 | switch (code) | |
6d716ca8 | 1084 | { |
e9a25f70 JL |
1085 | case BIT_IOR_EXPR: |
1086 | low = int1l | int2l, hi = int1h | int2h; | |
1087 | break; | |
6d716ca8 | 1088 | |
e9a25f70 JL |
1089 | case BIT_XOR_EXPR: |
1090 | low = int1l ^ int2l, hi = int1h ^ int2h; | |
1091 | break; | |
6d716ca8 | 1092 | |
e9a25f70 JL |
1093 | case BIT_AND_EXPR: |
1094 | low = int1l & int2l, hi = int1h & int2h; | |
1095 | break; | |
6d716ca8 | 1096 | |
e9a25f70 JL |
1097 | case BIT_ANDTC_EXPR: |
1098 | low = int1l & ~int2l, hi = int1h & ~int2h; | |
1099 | break; | |
6d716ca8 | 1100 | |
e9a25f70 JL |
1101 | case RSHIFT_EXPR: |
1102 | int2l = - int2l; | |
1103 | case LSHIFT_EXPR: | |
1104 | /* It's unclear from the C standard whether shifts can overflow. | |
1105 | The following code ignores overflow; perhaps a C standard | |
1106 | interpretation ruling is needed. */ | |
1107 | lshift_double (int1l, int1h, int2l, | |
1108 | TYPE_PRECISION (TREE_TYPE (arg1)), | |
1109 | &low, &hi, | |
1110 | !uns); | |
1111 | no_overflow = 1; | |
1112 | break; | |
6d716ca8 | 1113 | |
e9a25f70 JL |
1114 | case RROTATE_EXPR: |
1115 | int2l = - int2l; | |
1116 | case LROTATE_EXPR: | |
1117 | lrotate_double (int1l, int1h, int2l, | |
1118 | TYPE_PRECISION (TREE_TYPE (arg1)), | |
1119 | &low, &hi); | |
1120 | break; | |
6d716ca8 | 1121 | |
e9a25f70 JL |
1122 | case PLUS_EXPR: |
1123 | overflow = add_double (int1l, int1h, int2l, int2h, &low, &hi); | |
1124 | break; | |
6d716ca8 | 1125 | |
e9a25f70 JL |
1126 | case MINUS_EXPR: |
1127 | neg_double (int2l, int2h, &low, &hi); | |
1128 | add_double (int1l, int1h, low, hi, &low, &hi); | |
1129 | overflow = overflow_sum_sign (hi, int2h, int1h); | |
1130 | break; | |
6d716ca8 | 1131 | |
e9a25f70 JL |
1132 | case MULT_EXPR: |
1133 | overflow = mul_double (int1l, int1h, int2l, int2h, &low, &hi); | |
1134 | break; | |
6d716ca8 | 1135 | |
e9a25f70 JL |
1136 | case TRUNC_DIV_EXPR: |
1137 | case FLOOR_DIV_EXPR: case CEIL_DIV_EXPR: | |
1138 | case EXACT_DIV_EXPR: | |
1139 | /* This is a shortcut for a common special case. */ | |
1140 | if (int2h == 0 && int2l > 0 | |
1141 | && ! TREE_CONSTANT_OVERFLOW (arg1) | |
1142 | && ! TREE_CONSTANT_OVERFLOW (arg2) | |
1143 | && int1h == 0 && int1l >= 0) | |
1144 | { | |
1145 | if (code == CEIL_DIV_EXPR) | |
1146 | int1l += int2l - 1; | |
1147 | low = int1l / int2l, hi = 0; | |
6d716ca8 | 1148 | break; |
e9a25f70 | 1149 | } |
6d716ca8 | 1150 | |
e9a25f70 | 1151 | /* ... fall through ... */ |
6d716ca8 | 1152 | |
e9a25f70 JL |
1153 | case ROUND_DIV_EXPR: |
1154 | if (int2h == 0 && int2l == 1) | |
1155 | { | |
1156 | low = int1l, hi = int1h; | |
6d716ca8 | 1157 | break; |
e9a25f70 JL |
1158 | } |
1159 | if (int1l == int2l && int1h == int2h | |
1160 | && ! (int1l == 0 && int1h == 0)) | |
1161 | { | |
1162 | low = 1, hi = 0; | |
63e7fe9b | 1163 | break; |
e9a25f70 JL |
1164 | } |
1165 | overflow = div_and_round_double (code, uns, | |
1166 | int1l, int1h, int2l, int2h, | |
1167 | &low, &hi, &garbagel, &garbageh); | |
1168 | break; | |
63e7fe9b | 1169 | |
e9a25f70 JL |
1170 | case TRUNC_MOD_EXPR: |
1171 | case FLOOR_MOD_EXPR: case CEIL_MOD_EXPR: | |
1172 | /* This is a shortcut for a common special case. */ | |
1173 | if (int2h == 0 && int2l > 0 | |
1174 | && ! TREE_CONSTANT_OVERFLOW (arg1) | |
1175 | && ! TREE_CONSTANT_OVERFLOW (arg2) | |
1176 | && int1h == 0 && int1l >= 0) | |
1177 | { | |
1178 | if (code == CEIL_MOD_EXPR) | |
1179 | int1l += int2l - 1; | |
1180 | low = int1l % int2l, hi = 0; | |
63e7fe9b | 1181 | break; |
e9a25f70 | 1182 | } |
63e7fe9b | 1183 | |
e9a25f70 JL |
1184 | /* ... fall through ... */ |
1185 | ||
1186 | case ROUND_MOD_EXPR: | |
1187 | overflow = div_and_round_double (code, uns, | |
1188 | int1l, int1h, int2l, int2h, | |
1189 | &garbagel, &garbageh, &low, &hi); | |
1190 | break; | |
1191 | ||
1192 | case MIN_EXPR: | |
1193 | case MAX_EXPR: | |
1194 | if (uns) | |
1195 | { | |
1196 | low = (((unsigned HOST_WIDE_INT) int1h | |
1197 | < (unsigned HOST_WIDE_INT) int2h) | |
1198 | || (((unsigned HOST_WIDE_INT) int1h | |
1199 | == (unsigned HOST_WIDE_INT) int2h) | |
1200 | && ((unsigned HOST_WIDE_INT) int1l | |
1201 | < (unsigned HOST_WIDE_INT) int2l))); | |
6d716ca8 | 1202 | } |
380ff34a RK |
1203 | else |
1204 | { | |
e9a25f70 JL |
1205 | low = ((int1h < int2h) |
1206 | || ((int1h == int2h) | |
1207 | && ((unsigned HOST_WIDE_INT) int1l | |
1208 | < (unsigned HOST_WIDE_INT) int2l))); | |
380ff34a | 1209 | } |
e9a25f70 JL |
1210 | if (low == (code == MIN_EXPR)) |
1211 | low = int1l, hi = int1h; | |
1212 | else | |
1213 | low = int2l, hi = int2h; | |
1214 | break; | |
3dedc65a | 1215 | |
e9a25f70 JL |
1216 | default: |
1217 | abort (); | |
3dedc65a | 1218 | } |
e9a25f70 JL |
1219 | |
1220 | if (TREE_TYPE (arg1) == sizetype && hi == 0 | |
e1ee5cdc RH |
1221 | && low >= 0 |
1222 | && (TYPE_MAX_VALUE (sizetype) == NULL | |
1223 | || low <= TREE_INT_CST_LOW (TYPE_MAX_VALUE (sizetype))) | |
e9a25f70 JL |
1224 | && ! overflow |
1225 | && ! TREE_OVERFLOW (arg1) && ! TREE_OVERFLOW (arg2)) | |
1226 | t = size_int (low); | |
1227 | else | |
1228 | { | |
1229 | t = build_int_2 (low, hi); | |
1230 | TREE_TYPE (t) = TREE_TYPE (arg1); | |
1231 | } | |
1232 | ||
1233 | TREE_OVERFLOW (t) | |
1234 | = ((notrunc ? (!uns || forsize) && overflow | |
1235 | : force_fit_type (t, (!uns || forsize) && overflow) && ! no_overflow) | |
1236 | | TREE_OVERFLOW (arg1) | |
1237 | | TREE_OVERFLOW (arg2)); | |
1238 | /* If we're doing a size calculation, unsigned arithmetic does overflow. | |
1239 | So check if force_fit_type truncated the value. */ | |
1240 | if (forsize | |
1241 | && ! TREE_OVERFLOW (t) | |
1242 | && (TREE_INT_CST_HIGH (t) != hi | |
1243 | || TREE_INT_CST_LOW (t) != low)) | |
1244 | TREE_OVERFLOW (t) = 1; | |
1245 | TREE_CONSTANT_OVERFLOW (t) = (TREE_OVERFLOW (t) | |
1246 | | TREE_CONSTANT_OVERFLOW (arg1) | |
1247 | | TREE_CONSTANT_OVERFLOW (arg2)); | |
1248 | return t; | |
1249 | } | |
1250 | ||
1251 | /* Combine two constants ARG1 and ARG2 under operation CODE | |
1252 | to produce a new constant. | |
1253 | We assume ARG1 and ARG2 have the same data type, | |
1254 | or at least are the same kind of constant and the same machine mode. | |
1255 | ||
1256 | If NOTRUNC is nonzero, do not truncate the result to fit the data type. */ | |
1257 | ||
1258 | static tree | |
1259 | const_binop (code, arg1, arg2, notrunc) | |
1260 | enum tree_code code; | |
1261 | register tree arg1, arg2; | |
1262 | int notrunc; | |
1263 | { | |
1264 | STRIP_NOPS (arg1); STRIP_NOPS (arg2); | |
1265 | ||
1266 | if (TREE_CODE (arg1) == INTEGER_CST) | |
1267 | return int_const_binop (code, arg1, arg2, notrunc, 0); | |
1268 | ||
6d716ca8 RS |
1269 | #if ! defined (REAL_IS_NOT_DOUBLE) || defined (REAL_ARITHMETIC) |
1270 | if (TREE_CODE (arg1) == REAL_CST) | |
1271 | { | |
79c844cd RK |
1272 | REAL_VALUE_TYPE d1; |
1273 | REAL_VALUE_TYPE d2; | |
649ff3b4 | 1274 | int overflow = 0; |
5008b8ae | 1275 | REAL_VALUE_TYPE value; |
7c7b029d | 1276 | tree t; |
6d716ca8 | 1277 | |
79c844cd RK |
1278 | d1 = TREE_REAL_CST (arg1); |
1279 | d2 = TREE_REAL_CST (arg2); | |
5f610074 RK |
1280 | |
1281 | /* If either operand is a NaN, just return it. Otherwise, set up | |
1282 | for floating-point trap; we return an overflow. */ | |
1283 | if (REAL_VALUE_ISNAN (d1)) | |
1284 | return arg1; | |
1285 | else if (REAL_VALUE_ISNAN (d2)) | |
1286 | return arg2; | |
1287 | else if (setjmp (float_error)) | |
6d716ca8 | 1288 | { |
649ff3b4 RK |
1289 | t = copy_node (arg1); |
1290 | overflow = 1; | |
1291 | goto got_float; | |
6d716ca8 | 1292 | } |
649ff3b4 | 1293 | |
7c7b029d | 1294 | set_float_handler (float_error); |
6d716ca8 RS |
1295 | |
1296 | #ifdef REAL_ARITHMETIC | |
1297 | REAL_ARITHMETIC (value, code, d1, d2); | |
1298 | #else | |
1299 | switch (code) | |
1300 | { | |
1301 | case PLUS_EXPR: | |
1302 | value = d1 + d2; | |
1303 | break; | |
1304 | ||
1305 | case MINUS_EXPR: | |
1306 | value = d1 - d2; | |
1307 | break; | |
1308 | ||
1309 | case MULT_EXPR: | |
1310 | value = d1 * d2; | |
1311 | break; | |
1312 | ||
1313 | case RDIV_EXPR: | |
1314 | #ifndef REAL_INFINITY | |
1315 | if (d2 == 0) | |
1316 | abort (); | |
1317 | #endif | |
1318 | ||
1319 | value = d1 / d2; | |
1320 | break; | |
1321 | ||
1322 | case MIN_EXPR: | |
1323 | value = MIN (d1, d2); | |
1324 | break; | |
1325 | ||
1326 | case MAX_EXPR: | |
1327 | value = MAX (d1, d2); | |
1328 | break; | |
1329 | ||
1330 | default: | |
1331 | abort (); | |
1332 | } | |
1333 | #endif /* no REAL_ARITHMETIC */ | |
7c7b029d | 1334 | t = build_real (TREE_TYPE (arg1), |
5352b11a | 1335 | real_value_truncate (TYPE_MODE (TREE_TYPE (arg1)), value)); |
649ff3b4 | 1336 | got_float: |
906c4e36 | 1337 | set_float_handler (NULL_PTR); |
649ff3b4 RK |
1338 | |
1339 | TREE_OVERFLOW (t) | |
1340 | = (force_fit_type (t, overflow) | |
1341 | | TREE_OVERFLOW (arg1) | TREE_OVERFLOW (arg2)); | |
1342 | TREE_CONSTANT_OVERFLOW (t) | |
1343 | = TREE_OVERFLOW (t) | |
1344 | | TREE_CONSTANT_OVERFLOW (arg1) | |
1345 | | TREE_CONSTANT_OVERFLOW (arg2); | |
7c7b029d | 1346 | return t; |
6d716ca8 RS |
1347 | } |
1348 | #endif /* not REAL_IS_NOT_DOUBLE, or REAL_ARITHMETIC */ | |
1349 | if (TREE_CODE (arg1) == COMPLEX_CST) | |
1350 | { | |
214d5b84 | 1351 | register tree type = TREE_TYPE (arg1); |
6d716ca8 RS |
1352 | register tree r1 = TREE_REALPART (arg1); |
1353 | register tree i1 = TREE_IMAGPART (arg1); | |
1354 | register tree r2 = TREE_REALPART (arg2); | |
1355 | register tree i2 = TREE_IMAGPART (arg2); | |
1356 | register tree t; | |
1357 | ||
1358 | switch (code) | |
1359 | { | |
1360 | case PLUS_EXPR: | |
214d5b84 RK |
1361 | t = build_complex (type, |
1362 | const_binop (PLUS_EXPR, r1, r2, notrunc), | |
91d33e36 | 1363 | const_binop (PLUS_EXPR, i1, i2, notrunc)); |
6d716ca8 RS |
1364 | break; |
1365 | ||
1366 | case MINUS_EXPR: | |
214d5b84 RK |
1367 | t = build_complex (type, |
1368 | const_binop (MINUS_EXPR, r1, r2, notrunc), | |
91d33e36 | 1369 | const_binop (MINUS_EXPR, i1, i2, notrunc)); |
6d716ca8 RS |
1370 | break; |
1371 | ||
1372 | case MULT_EXPR: | |
214d5b84 RK |
1373 | t = build_complex (type, |
1374 | const_binop (MINUS_EXPR, | |
91d33e36 RS |
1375 | const_binop (MULT_EXPR, |
1376 | r1, r2, notrunc), | |
1377 | const_binop (MULT_EXPR, | |
1378 | i1, i2, notrunc), | |
1379 | notrunc), | |
6d716ca8 | 1380 | const_binop (PLUS_EXPR, |
91d33e36 RS |
1381 | const_binop (MULT_EXPR, |
1382 | r1, i2, notrunc), | |
1383 | const_binop (MULT_EXPR, | |
1384 | i1, r2, notrunc), | |
1385 | notrunc)); | |
6d716ca8 RS |
1386 | break; |
1387 | ||
1388 | case RDIV_EXPR: | |
1389 | { | |
1390 | register tree magsquared | |
1391 | = const_binop (PLUS_EXPR, | |
91d33e36 RS |
1392 | const_binop (MULT_EXPR, r2, r2, notrunc), |
1393 | const_binop (MULT_EXPR, i2, i2, notrunc), | |
1394 | notrunc); | |
58633be8 | 1395 | |
214d5b84 RK |
1396 | t = build_complex (type, |
1397 | const_binop | |
1398 | (INTEGRAL_TYPE_P (TREE_TYPE (r1)) | |
1399 | ? TRUNC_DIV_EXPR : RDIV_EXPR, | |
1400 | const_binop (PLUS_EXPR, | |
1401 | const_binop (MULT_EXPR, r1, r2, | |
1402 | notrunc), | |
1403 | const_binop (MULT_EXPR, i1, i2, | |
1404 | notrunc), | |
1405 | notrunc), | |
1406 | magsquared, notrunc), | |
1407 | const_binop | |
1408 | (INTEGRAL_TYPE_P (TREE_TYPE (r1)) | |
1409 | ? TRUNC_DIV_EXPR : RDIV_EXPR, | |
1410 | const_binop (MINUS_EXPR, | |
1411 | const_binop (MULT_EXPR, i1, r2, | |
1412 | notrunc), | |
1413 | const_binop (MULT_EXPR, r1, i2, | |
1414 | notrunc), | |
1415 | notrunc), | |
1416 | magsquared, notrunc)); | |
6d716ca8 RS |
1417 | } |
1418 | break; | |
1419 | ||
1420 | default: | |
1421 | abort (); | |
1422 | } | |
6d716ca8 RS |
1423 | return t; |
1424 | } | |
1425 | return 0; | |
1426 | } | |
1427 | \f | |
f8dac6eb R |
1428 | /* Return an INTEGER_CST with value V . The type is determined by bit_p: |
1429 | if it is zero, the type is taken from sizetype; if it is one, the type | |
1430 | is taken from bitsizetype. */ | |
6d716ca8 RS |
1431 | |
1432 | tree | |
f8dac6eb R |
1433 | size_int_wide (number, high, bit_p) |
1434 | unsigned HOST_WIDE_INT number, high; | |
2fde567e | 1435 | int bit_p; |
6d716ca8 RS |
1436 | { |
1437 | register tree t; | |
1438 | /* Type-size nodes already made for small sizes. */ | |
f8dac6eb | 1439 | static tree size_table[2*HOST_BITS_PER_WIDE_INT + 1][2]; |
6d716ca8 | 1440 | |
f8dac6eb R |
1441 | if (number < 2*HOST_BITS_PER_WIDE_INT + 1 && ! high |
1442 | && size_table[number][bit_p] != 0) | |
1443 | return size_table[number][bit_p]; | |
1444 | if (number < 2*HOST_BITS_PER_WIDE_INT + 1 && ! high) | |
6d716ca8 | 1445 | { |
6d716ca8 RS |
1446 | push_obstacks_nochange (); |
1447 | /* Make this a permanent node. */ | |
c05a9b68 | 1448 | end_temporary_allocation (); |
6d716ca8 | 1449 | t = build_int_2 (number, 0); |
896cced4 | 1450 | TREE_TYPE (t) = bit_p ? bitsizetype : sizetype; |
f8dac6eb | 1451 | size_table[number][bit_p] = t; |
6d716ca8 RS |
1452 | pop_obstacks (); |
1453 | } | |
1454 | else | |
1455 | { | |
f8dac6eb | 1456 | t = build_int_2 (number, high); |
896cced4 | 1457 | TREE_TYPE (t) = bit_p ? bitsizetype : sizetype; |
380ff34a | 1458 | TREE_OVERFLOW (t) = TREE_CONSTANT_OVERFLOW (t) = force_fit_type (t, 0); |
6d716ca8 RS |
1459 | } |
1460 | return t; | |
1461 | } | |
1462 | ||
1463 | /* Combine operands OP1 and OP2 with arithmetic operation CODE. | |
1464 | CODE is a tree code. Data type is taken from `sizetype', | |
1465 | If the operands are constant, so is the result. */ | |
1466 | ||
1467 | tree | |
1468 | size_binop (code, arg0, arg1) | |
1469 | enum tree_code code; | |
1470 | tree arg0, arg1; | |
1471 | { | |
1472 | /* Handle the special case of two integer constants faster. */ | |
1473 | if (TREE_CODE (arg0) == INTEGER_CST && TREE_CODE (arg1) == INTEGER_CST) | |
1474 | { | |
1475 | /* And some specific cases even faster than that. */ | |
9898deac | 1476 | if (code == PLUS_EXPR && integer_zerop (arg0)) |
6d716ca8 | 1477 | return arg1; |
9898deac RK |
1478 | else if ((code == MINUS_EXPR || code == PLUS_EXPR) |
1479 | && integer_zerop (arg1)) | |
6d716ca8 | 1480 | return arg0; |
9898deac | 1481 | else if (code == MULT_EXPR && integer_onep (arg0)) |
6d716ca8 | 1482 | return arg1; |
9898deac | 1483 | |
6d716ca8 | 1484 | /* Handle general case of two integer constants. */ |
e9a25f70 | 1485 | return int_const_binop (code, arg0, arg1, 0, 1); |
6d716ca8 RS |
1486 | } |
1487 | ||
1488 | if (arg0 == error_mark_node || arg1 == error_mark_node) | |
1489 | return error_mark_node; | |
1490 | ||
1491 | return fold (build (code, sizetype, arg0, arg1)); | |
1492 | } | |
697073d9 JM |
1493 | |
1494 | /* Combine operands OP1 and OP2 with arithmetic operation CODE. | |
1495 | CODE is a tree code. Data type is taken from `ssizetype', | |
1496 | If the operands are constant, so is the result. */ | |
1497 | ||
1498 | tree | |
1499 | ssize_binop (code, arg0, arg1) | |
1500 | enum tree_code code; | |
1501 | tree arg0, arg1; | |
1502 | { | |
1503 | /* Handle the special case of two integer constants faster. */ | |
1504 | if (TREE_CODE (arg0) == INTEGER_CST && TREE_CODE (arg1) == INTEGER_CST) | |
1505 | { | |
1506 | /* And some specific cases even faster than that. */ | |
1507 | if (code == PLUS_EXPR && integer_zerop (arg0)) | |
1508 | return arg1; | |
1509 | else if ((code == MINUS_EXPR || code == PLUS_EXPR) | |
1510 | && integer_zerop (arg1)) | |
1511 | return arg0; | |
1512 | else if (code == MULT_EXPR && integer_onep (arg0)) | |
1513 | return arg1; | |
1514 | ||
1515 | /* Handle general case of two integer constants. We convert | |
1516 | arg0 to ssizetype because int_const_binop uses its type for the | |
1517 | return value. */ | |
1518 | arg0 = convert (ssizetype, arg0); | |
1519 | return int_const_binop (code, arg0, arg1, 0, 0); | |
1520 | } | |
1521 | ||
1522 | if (arg0 == error_mark_node || arg1 == error_mark_node) | |
1523 | return error_mark_node; | |
1524 | ||
1525 | return fold (build (code, ssizetype, arg0, arg1)); | |
1526 | } | |
6d716ca8 RS |
1527 | \f |
1528 | /* Given T, a tree representing type conversion of ARG1, a constant, | |
1529 | return a constant tree representing the result of conversion. */ | |
1530 | ||
1531 | static tree | |
1532 | fold_convert (t, arg1) | |
1533 | register tree t; | |
1534 | register tree arg1; | |
1535 | { | |
1536 | register tree type = TREE_TYPE (t); | |
649ff3b4 | 1537 | int overflow = 0; |
6d716ca8 | 1538 | |
e5e809f4 | 1539 | if (POINTER_TYPE_P (type) || INTEGRAL_TYPE_P (type)) |
6d716ca8 RS |
1540 | { |
1541 | if (TREE_CODE (arg1) == INTEGER_CST) | |
1542 | { | |
e3374525 RK |
1543 | /* If we would build a constant wider than GCC supports, |
1544 | leave the conversion unfolded. */ | |
1545 | if (TYPE_PRECISION (type) > 2 * HOST_BITS_PER_WIDE_INT) | |
1546 | return t; | |
1547 | ||
6d716ca8 RS |
1548 | /* Given an integer constant, make new constant with new type, |
1549 | appropriately sign-extended or truncated. */ | |
1550 | t = build_int_2 (TREE_INT_CST_LOW (arg1), | |
1551 | TREE_INT_CST_HIGH (arg1)); | |
1552 | TREE_TYPE (t) = type; | |
e0f776fb | 1553 | /* Indicate an overflow if (1) ARG1 already overflowed, |
dc3907c5 PE |
1554 | or (2) force_fit_type indicates an overflow. |
1555 | Tell force_fit_type that an overflow has already occurred | |
b472527b JL |
1556 | if ARG1 is a too-large unsigned value and T is signed. |
1557 | But don't indicate an overflow if converting a pointer. */ | |
dc3907c5 | 1558 | TREE_OVERFLOW (t) |
e5e809f4 JL |
1559 | = ((force_fit_type (t, |
1560 | (TREE_INT_CST_HIGH (arg1) < 0 | |
4f242db3 | 1561 | && (TREE_UNSIGNED (type) |
e5e809f4 JL |
1562 | < TREE_UNSIGNED (TREE_TYPE (arg1))))) |
1563 | && ! POINTER_TYPE_P (TREE_TYPE (arg1))) | |
1564 | || TREE_OVERFLOW (arg1)); | |
dc3907c5 PE |
1565 | TREE_CONSTANT_OVERFLOW (t) |
1566 | = TREE_OVERFLOW (t) | TREE_CONSTANT_OVERFLOW (arg1); | |
6d716ca8 RS |
1567 | } |
1568 | #if !defined (REAL_IS_NOT_DOUBLE) || defined (REAL_ARITHMETIC) | |
1569 | else if (TREE_CODE (arg1) == REAL_CST) | |
1570 | { | |
4b8a0062 RK |
1571 | /* Don't initialize these, use assignments. |
1572 | Initialized local aggregates don't work on old compilers. */ | |
1573 | REAL_VALUE_TYPE x; | |
1574 | REAL_VALUE_TYPE l; | |
1575 | REAL_VALUE_TYPE u; | |
7cb6a121 | 1576 | tree type1 = TREE_TYPE (arg1); |
e1ee5cdc | 1577 | int no_upper_bound; |
4b8a0062 RK |
1578 | |
1579 | x = TREE_REAL_CST (arg1); | |
7cb6a121 | 1580 | l = real_value_from_int_cst (type1, TYPE_MIN_VALUE (type)); |
e1ee5cdc RH |
1581 | |
1582 | no_upper_bound = (TYPE_MAX_VALUE (type) == NULL); | |
1583 | if (!no_upper_bound) | |
1584 | u = real_value_from_int_cst (type1, TYPE_MAX_VALUE (type)); | |
1585 | ||
4b3d5ea0 RS |
1586 | /* See if X will be in range after truncation towards 0. |
1587 | To compensate for truncation, move the bounds away from 0, | |
1588 | but reject if X exactly equals the adjusted bounds. */ | |
1589 | #ifdef REAL_ARITHMETIC | |
1590 | REAL_ARITHMETIC (l, MINUS_EXPR, l, dconst1); | |
e1ee5cdc RH |
1591 | if (!no_upper_bound) |
1592 | REAL_ARITHMETIC (u, PLUS_EXPR, u, dconst1); | |
4b3d5ea0 RS |
1593 | #else |
1594 | l--; | |
e1ee5cdc RH |
1595 | if (!no_upper_bound) |
1596 | u++; | |
4b3d5ea0 | 1597 | #endif |
5f610074 RK |
1598 | /* If X is a NaN, use zero instead and show we have an overflow. |
1599 | Otherwise, range check. */ | |
1600 | if (REAL_VALUE_ISNAN (x)) | |
1601 | overflow = 1, x = dconst0; | |
e1ee5cdc RH |
1602 | else if (! (REAL_VALUES_LESS (l, x) |
1603 | && !no_upper_bound | |
1604 | && REAL_VALUES_LESS (x, u))) | |
649ff3b4 RK |
1605 | overflow = 1; |
1606 | ||
6d716ca8 RS |
1607 | #ifndef REAL_ARITHMETIC |
1608 | { | |
906c4e36 RK |
1609 | HOST_WIDE_INT low, high; |
1610 | HOST_WIDE_INT half_word | |
1611 | = (HOST_WIDE_INT) 1 << (HOST_BITS_PER_WIDE_INT / 2); | |
6d716ca8 | 1612 | |
5f610074 RK |
1613 | if (x < 0) |
1614 | x = -x; | |
6d716ca8 | 1615 | |
5f610074 RK |
1616 | high = (HOST_WIDE_INT) (x / half_word / half_word); |
1617 | x -= (REAL_VALUE_TYPE) high * half_word * half_word; | |
1618 | if (x >= (REAL_VALUE_TYPE) half_word * half_word / 2) | |
b6b19f41 | 1619 | { |
5f610074 | 1620 | low = x - (REAL_VALUE_TYPE) half_word * half_word / 2; |
e0f776fb | 1621 | low |= (HOST_WIDE_INT) -1 << (HOST_BITS_PER_WIDE_INT - 1); |
b6b19f41 RS |
1622 | } |
1623 | else | |
5f610074 | 1624 | low = (HOST_WIDE_INT) x; |
6d716ca8 RS |
1625 | if (TREE_REAL_CST (arg1) < 0) |
1626 | neg_double (low, high, &low, &high); | |
1627 | t = build_int_2 (low, high); | |
1628 | } | |
1629 | #else | |
1630 | { | |
906c4e36 | 1631 | HOST_WIDE_INT low, high; |
5f610074 | 1632 | REAL_VALUE_TO_INT (&low, &high, x); |
6d716ca8 RS |
1633 | t = build_int_2 (low, high); |
1634 | } | |
1635 | #endif | |
1636 | TREE_TYPE (t) = type; | |
649ff3b4 RK |
1637 | TREE_OVERFLOW (t) |
1638 | = TREE_OVERFLOW (arg1) | force_fit_type (t, overflow); | |
1639 | TREE_CONSTANT_OVERFLOW (t) | |
1640 | = TREE_OVERFLOW (t) | TREE_CONSTANT_OVERFLOW (arg1); | |
6d716ca8 RS |
1641 | } |
1642 | #endif /* not REAL_IS_NOT_DOUBLE, or REAL_ARITHMETIC */ | |
1643 | TREE_TYPE (t) = type; | |
1644 | } | |
1645 | else if (TREE_CODE (type) == REAL_TYPE) | |
1646 | { | |
1647 | #if !defined (REAL_IS_NOT_DOUBLE) || defined (REAL_ARITHMETIC) | |
1648 | if (TREE_CODE (arg1) == INTEGER_CST) | |
1649 | return build_real_from_int_cst (type, arg1); | |
1650 | #endif /* not REAL_IS_NOT_DOUBLE, or REAL_ARITHMETIC */ | |
1651 | if (TREE_CODE (arg1) == REAL_CST) | |
7c7b029d | 1652 | { |
5f610074 | 1653 | if (REAL_VALUE_ISNAN (TREE_REAL_CST (arg1))) |
a377ff85 RK |
1654 | { |
1655 | t = arg1; | |
1656 | TREE_TYPE (arg1) = type; | |
1657 | return t; | |
1658 | } | |
5f610074 | 1659 | else if (setjmp (float_error)) |
7c7b029d | 1660 | { |
649ff3b4 RK |
1661 | overflow = 1; |
1662 | t = copy_node (arg1); | |
1663 | goto got_it; | |
7c7b029d RS |
1664 | } |
1665 | set_float_handler (float_error); | |
1666 | ||
5352b11a | 1667 | t = build_real (type, real_value_truncate (TYPE_MODE (type), |
7c7b029d | 1668 | TREE_REAL_CST (arg1))); |
906c4e36 | 1669 | set_float_handler (NULL_PTR); |
649ff3b4 RK |
1670 | |
1671 | got_it: | |
1672 | TREE_OVERFLOW (t) | |
1673 | = TREE_OVERFLOW (arg1) | force_fit_type (t, overflow); | |
1674 | TREE_CONSTANT_OVERFLOW (t) | |
1675 | = TREE_OVERFLOW (t) | TREE_CONSTANT_OVERFLOW (arg1); | |
7c7b029d RS |
1676 | return t; |
1677 | } | |
6d716ca8 RS |
1678 | } |
1679 | TREE_CONSTANT (t) = 1; | |
1680 | return t; | |
1681 | } | |
1682 | \f | |
ff59bfe6 | 1683 | /* Return an expr equal to X but certainly not valid as an lvalue. */ |
6d716ca8 RS |
1684 | |
1685 | tree | |
1686 | non_lvalue (x) | |
1687 | tree x; | |
1688 | { | |
1689 | tree result; | |
1690 | ||
1691 | /* These things are certainly not lvalues. */ | |
1692 | if (TREE_CODE (x) == NON_LVALUE_EXPR | |
1693 | || TREE_CODE (x) == INTEGER_CST | |
1694 | || TREE_CODE (x) == REAL_CST | |
1695 | || TREE_CODE (x) == STRING_CST | |
1696 | || TREE_CODE (x) == ADDR_EXPR) | |
ff59bfe6 | 1697 | return x; |
6d716ca8 RS |
1698 | |
1699 | result = build1 (NON_LVALUE_EXPR, TREE_TYPE (x), x); | |
1700 | TREE_CONSTANT (result) = TREE_CONSTANT (x); | |
1701 | return result; | |
1702 | } | |
a5e9b124 | 1703 | |
e9866da3 JM |
1704 | /* Nonzero means lvalues are limited to those valid in pedantic ANSI C. |
1705 | Zero means allow extended lvalues. */ | |
1706 | ||
1707 | int pedantic_lvalues; | |
1708 | ||
a5e9b124 JW |
1709 | /* When pedantic, return an expr equal to X but certainly not valid as a |
1710 | pedantic lvalue. Otherwise, return X. */ | |
1711 | ||
1712 | tree | |
1713 | pedantic_non_lvalue (x) | |
1714 | tree x; | |
1715 | { | |
e9866da3 | 1716 | if (pedantic_lvalues) |
a5e9b124 JW |
1717 | return non_lvalue (x); |
1718 | else | |
1719 | return x; | |
1720 | } | |
c05a9b68 RS |
1721 | \f |
1722 | /* Given a tree comparison code, return the code that is the logical inverse | |
1723 | of the given code. It is not safe to do this for floating-point | |
1724 | comparisons, except for NE_EXPR and EQ_EXPR. */ | |
6d716ca8 | 1725 | |
c05a9b68 RS |
1726 | static enum tree_code |
1727 | invert_tree_comparison (code) | |
1728 | enum tree_code code; | |
1729 | { | |
1730 | switch (code) | |
1731 | { | |
1732 | case EQ_EXPR: | |
1733 | return NE_EXPR; | |
1734 | case NE_EXPR: | |
1735 | return EQ_EXPR; | |
1736 | case GT_EXPR: | |
1737 | return LE_EXPR; | |
1738 | case GE_EXPR: | |
1739 | return LT_EXPR; | |
1740 | case LT_EXPR: | |
1741 | return GE_EXPR; | |
1742 | case LE_EXPR: | |
1743 | return GT_EXPR; | |
1744 | default: | |
1745 | abort (); | |
1746 | } | |
1747 | } | |
1748 | ||
1749 | /* Similar, but return the comparison that results if the operands are | |
1750 | swapped. This is safe for floating-point. */ | |
1751 | ||
1752 | static enum tree_code | |
1753 | swap_tree_comparison (code) | |
1754 | enum tree_code code; | |
1755 | { | |
1756 | switch (code) | |
1757 | { | |
1758 | case EQ_EXPR: | |
1759 | case NE_EXPR: | |
1760 | return code; | |
1761 | case GT_EXPR: | |
1762 | return LT_EXPR; | |
1763 | case GE_EXPR: | |
1764 | return LE_EXPR; | |
1765 | case LT_EXPR: | |
1766 | return GT_EXPR; | |
1767 | case LE_EXPR: | |
1768 | return GE_EXPR; | |
1769 | default: | |
1770 | abort (); | |
1771 | } | |
1772 | } | |
61f275ff RK |
1773 | |
1774 | /* Return nonzero if CODE is a tree code that represents a truth value. */ | |
1775 | ||
1776 | static int | |
1777 | truth_value_p (code) | |
1778 | enum tree_code code; | |
1779 | { | |
1780 | return (TREE_CODE_CLASS (code) == '<' | |
1781 | || code == TRUTH_AND_EXPR || code == TRUTH_ANDIF_EXPR | |
1782 | || code == TRUTH_OR_EXPR || code == TRUTH_ORIF_EXPR | |
1783 | || code == TRUTH_XOR_EXPR || code == TRUTH_NOT_EXPR); | |
1784 | } | |
c05a9b68 | 1785 | \f |
6a1746af RS |
1786 | /* Return nonzero if two operands are necessarily equal. |
1787 | If ONLY_CONST is non-zero, only return non-zero for constants. | |
1788 | This function tests whether the operands are indistinguishable; | |
1789 | it does not test whether they are equal using C's == operation. | |
1790 | The distinction is important for IEEE floating point, because | |
1791 | (1) -0.0 and 0.0 are distinguishable, but -0.0==0.0, and | |
1792 | (2) two NaNs may be indistinguishable, but NaN!=NaN. */ | |
6d716ca8 RS |
1793 | |
1794 | int | |
1795 | operand_equal_p (arg0, arg1, only_const) | |
1796 | tree arg0, arg1; | |
1797 | int only_const; | |
1798 | { | |
1799 | /* If both types don't have the same signedness, then we can't consider | |
1800 | them equal. We must check this before the STRIP_NOPS calls | |
1801 | because they may change the signedness of the arguments. */ | |
1802 | if (TREE_UNSIGNED (TREE_TYPE (arg0)) != TREE_UNSIGNED (TREE_TYPE (arg1))) | |
1803 | return 0; | |
1804 | ||
1805 | STRIP_NOPS (arg0); | |
1806 | STRIP_NOPS (arg1); | |
1807 | ||
c7cfe938 RK |
1808 | if (TREE_CODE (arg0) != TREE_CODE (arg1) |
1809 | /* This is needed for conversions and for COMPONENT_REF. | |
1810 | Might as well play it safe and always test this. */ | |
1811 | || TYPE_MODE (TREE_TYPE (arg0)) != TYPE_MODE (TREE_TYPE (arg1))) | |
6d716ca8 RS |
1812 | return 0; |
1813 | ||
c7cfe938 RK |
1814 | /* If ARG0 and ARG1 are the same SAVE_EXPR, they are necessarily equal. |
1815 | We don't care about side effects in that case because the SAVE_EXPR | |
1816 | takes care of that for us. In all other cases, two expressions are | |
1817 | equal if they have no side effects. If we have two identical | |
1818 | expressions with side effects that should be treated the same due | |
1819 | to the only side effects being identical SAVE_EXPR's, that will | |
1820 | be detected in the recursive calls below. */ | |
1821 | if (arg0 == arg1 && ! only_const | |
1822 | && (TREE_CODE (arg0) == SAVE_EXPR | |
1823 | || (! TREE_SIDE_EFFECTS (arg0) && ! TREE_SIDE_EFFECTS (arg1)))) | |
6d716ca8 RS |
1824 | return 1; |
1825 | ||
c7cfe938 RK |
1826 | /* Next handle constant cases, those for which we can return 1 even |
1827 | if ONLY_CONST is set. */ | |
1828 | if (TREE_CONSTANT (arg0) && TREE_CONSTANT (arg1)) | |
1829 | switch (TREE_CODE (arg0)) | |
1830 | { | |
1831 | case INTEGER_CST: | |
3c9b0091 RK |
1832 | return (! TREE_CONSTANT_OVERFLOW (arg0) |
1833 | && ! TREE_CONSTANT_OVERFLOW (arg1) | |
1834 | && TREE_INT_CST_LOW (arg0) == TREE_INT_CST_LOW (arg1) | |
c7cfe938 RK |
1835 | && TREE_INT_CST_HIGH (arg0) == TREE_INT_CST_HIGH (arg1)); |
1836 | ||
1837 | case REAL_CST: | |
3c9b0091 RK |
1838 | return (! TREE_CONSTANT_OVERFLOW (arg0) |
1839 | && ! TREE_CONSTANT_OVERFLOW (arg1) | |
41c9120b PE |
1840 | && REAL_VALUES_IDENTICAL (TREE_REAL_CST (arg0), |
1841 | TREE_REAL_CST (arg1))); | |
c7cfe938 RK |
1842 | |
1843 | case COMPLEX_CST: | |
1844 | return (operand_equal_p (TREE_REALPART (arg0), TREE_REALPART (arg1), | |
1845 | only_const) | |
1846 | && operand_equal_p (TREE_IMAGPART (arg0), TREE_IMAGPART (arg1), | |
1847 | only_const)); | |
1848 | ||
1849 | case STRING_CST: | |
1850 | return (TREE_STRING_LENGTH (arg0) == TREE_STRING_LENGTH (arg1) | |
1851 | && ! strncmp (TREE_STRING_POINTER (arg0), | |
1852 | TREE_STRING_POINTER (arg1), | |
1853 | TREE_STRING_LENGTH (arg0))); | |
1854 | ||
1855 | case ADDR_EXPR: | |
1856 | return operand_equal_p (TREE_OPERAND (arg0, 0), TREE_OPERAND (arg1, 0), | |
1857 | 0); | |
e9a25f70 JL |
1858 | default: |
1859 | break; | |
c7cfe938 | 1860 | } |
6d716ca8 RS |
1861 | |
1862 | if (only_const) | |
1863 | return 0; | |
1864 | ||
6d716ca8 RS |
1865 | switch (TREE_CODE_CLASS (TREE_CODE (arg0))) |
1866 | { | |
1867 | case '1': | |
1868 | /* Two conversions are equal only if signedness and modes match. */ | |
1869 | if ((TREE_CODE (arg0) == NOP_EXPR || TREE_CODE (arg0) == CONVERT_EXPR) | |
1870 | && (TREE_UNSIGNED (TREE_TYPE (arg0)) | |
1871 | != TREE_UNSIGNED (TREE_TYPE (arg1)))) | |
1872 | return 0; | |
1873 | ||
1874 | return operand_equal_p (TREE_OPERAND (arg0, 0), | |
1875 | TREE_OPERAND (arg1, 0), 0); | |
1876 | ||
1877 | case '<': | |
1878 | case '2': | |
c7cfe938 RK |
1879 | if (operand_equal_p (TREE_OPERAND (arg0, 0), TREE_OPERAND (arg1, 0), 0) |
1880 | && operand_equal_p (TREE_OPERAND (arg0, 1), TREE_OPERAND (arg1, 1), | |
1881 | 0)) | |
1882 | return 1; | |
1883 | ||
1884 | /* For commutative ops, allow the other order. */ | |
1885 | return ((TREE_CODE (arg0) == PLUS_EXPR || TREE_CODE (arg0) == MULT_EXPR | |
1886 | || TREE_CODE (arg0) == MIN_EXPR || TREE_CODE (arg0) == MAX_EXPR | |
1887 | || TREE_CODE (arg0) == BIT_IOR_EXPR | |
1888 | || TREE_CODE (arg0) == BIT_XOR_EXPR | |
1889 | || TREE_CODE (arg0) == BIT_AND_EXPR | |
1890 | || TREE_CODE (arg0) == NE_EXPR || TREE_CODE (arg0) == EQ_EXPR) | |
1891 | && operand_equal_p (TREE_OPERAND (arg0, 0), | |
1892 | TREE_OPERAND (arg1, 1), 0) | |
6d716ca8 | 1893 | && operand_equal_p (TREE_OPERAND (arg0, 1), |
c7cfe938 | 1894 | TREE_OPERAND (arg1, 0), 0)); |
6d716ca8 RS |
1895 | |
1896 | case 'r': | |
1897 | switch (TREE_CODE (arg0)) | |
1898 | { | |
1899 | case INDIRECT_REF: | |
1900 | return operand_equal_p (TREE_OPERAND (arg0, 0), | |
1901 | TREE_OPERAND (arg1, 0), 0); | |
1902 | ||
1903 | case COMPONENT_REF: | |
1904 | case ARRAY_REF: | |
1905 | return (operand_equal_p (TREE_OPERAND (arg0, 0), | |
1906 | TREE_OPERAND (arg1, 0), 0) | |
1907 | && operand_equal_p (TREE_OPERAND (arg0, 1), | |
1908 | TREE_OPERAND (arg1, 1), 0)); | |
1909 | ||
1910 | case BIT_FIELD_REF: | |
1911 | return (operand_equal_p (TREE_OPERAND (arg0, 0), | |
1912 | TREE_OPERAND (arg1, 0), 0) | |
1913 | && operand_equal_p (TREE_OPERAND (arg0, 1), | |
1914 | TREE_OPERAND (arg1, 1), 0) | |
1915 | && operand_equal_p (TREE_OPERAND (arg0, 2), | |
1916 | TREE_OPERAND (arg1, 2), 0)); | |
e9a25f70 JL |
1917 | default: |
1918 | return 0; | |
6d716ca8 | 1919 | } |
45f97e2e RH |
1920 | |
1921 | case 'e': | |
1922 | if (TREE_CODE (arg0) == RTL_EXPR) | |
1923 | return rtx_equal_p (RTL_EXPR_RTL (arg0), RTL_EXPR_RTL (arg1)); | |
1924 | return 0; | |
e9a25f70 JL |
1925 | |
1926 | default: | |
1927 | return 0; | |
6d716ca8 | 1928 | } |
6d716ca8 | 1929 | } |
c05a9b68 RS |
1930 | \f |
1931 | /* Similar to operand_equal_p, but see if ARG0 might have been made by | |
1932 | shorten_compare from ARG1 when ARG1 was being compared with OTHER. | |
6d716ca8 | 1933 | |
6d716ca8 RS |
1934 | When in doubt, return 0. */ |
1935 | ||
1936 | static int | |
c05a9b68 RS |
1937 | operand_equal_for_comparison_p (arg0, arg1, other) |
1938 | tree arg0, arg1; | |
1939 | tree other; | |
6d716ca8 | 1940 | { |
c05a9b68 | 1941 | int unsignedp1, unsignedpo; |
52de9b6c | 1942 | tree primarg0, primarg1, primother; |
7a75868d | 1943 | unsigned correct_width; |
6d716ca8 | 1944 | |
c05a9b68 | 1945 | if (operand_equal_p (arg0, arg1, 0)) |
6d716ca8 RS |
1946 | return 1; |
1947 | ||
0982a4b8 JM |
1948 | if (! INTEGRAL_TYPE_P (TREE_TYPE (arg0)) |
1949 | || ! INTEGRAL_TYPE_P (TREE_TYPE (arg1))) | |
6d716ca8 RS |
1950 | return 0; |
1951 | ||
52de9b6c RK |
1952 | /* Discard any conversions that don't change the modes of ARG0 and ARG1 |
1953 | and see if the inner values are the same. This removes any | |
1954 | signedness comparison, which doesn't matter here. */ | |
1955 | primarg0 = arg0, primarg1 = arg1; | |
1956 | STRIP_NOPS (primarg0); STRIP_NOPS (primarg1); | |
1957 | if (operand_equal_p (primarg0, primarg1, 0)) | |
1958 | return 1; | |
1959 | ||
c05a9b68 RS |
1960 | /* Duplicate what shorten_compare does to ARG1 and see if that gives the |
1961 | actual comparison operand, ARG0. | |
6d716ca8 | 1962 | |
c05a9b68 | 1963 | First throw away any conversions to wider types |
6d716ca8 | 1964 | already present in the operands. */ |
6d716ca8 | 1965 | |
c05a9b68 RS |
1966 | primarg1 = get_narrower (arg1, &unsignedp1); |
1967 | primother = get_narrower (other, &unsignedpo); | |
1968 | ||
1969 | correct_width = TYPE_PRECISION (TREE_TYPE (arg1)); | |
1970 | if (unsignedp1 == unsignedpo | |
1971 | && TYPE_PRECISION (TREE_TYPE (primarg1)) < correct_width | |
1972 | && TYPE_PRECISION (TREE_TYPE (primother)) < correct_width) | |
6d716ca8 | 1973 | { |
c05a9b68 | 1974 | tree type = TREE_TYPE (arg0); |
6d716ca8 RS |
1975 | |
1976 | /* Make sure shorter operand is extended the right way | |
1977 | to match the longer operand. */ | |
c05a9b68 RS |
1978 | primarg1 = convert (signed_or_unsigned_type (unsignedp1, |
1979 | TREE_TYPE (primarg1)), | |
1980 | primarg1); | |
6d716ca8 | 1981 | |
c05a9b68 | 1982 | if (operand_equal_p (arg0, convert (type, primarg1), 0)) |
6d716ca8 RS |
1983 | return 1; |
1984 | } | |
1985 | ||
1986 | return 0; | |
1987 | } | |
1988 | \f | |
f72aed24 | 1989 | /* See if ARG is an expression that is either a comparison or is performing |
c05a9b68 RS |
1990 | arithmetic on comparisons. The comparisons must only be comparing |
1991 | two different values, which will be stored in *CVAL1 and *CVAL2; if | |
1992 | they are non-zero it means that some operands have already been found. | |
1993 | No variables may be used anywhere else in the expression except in the | |
35e66bd1 RK |
1994 | comparisons. If SAVE_P is true it means we removed a SAVE_EXPR around |
1995 | the expression and save_expr needs to be called with CVAL1 and CVAL2. | |
c05a9b68 RS |
1996 | |
1997 | If this is true, return 1. Otherwise, return zero. */ | |
1998 | ||
1999 | static int | |
35e66bd1 | 2000 | twoval_comparison_p (arg, cval1, cval2, save_p) |
c05a9b68 RS |
2001 | tree arg; |
2002 | tree *cval1, *cval2; | |
35e66bd1 | 2003 | int *save_p; |
c05a9b68 RS |
2004 | { |
2005 | enum tree_code code = TREE_CODE (arg); | |
2006 | char class = TREE_CODE_CLASS (code); | |
2007 | ||
2008 | /* We can handle some of the 'e' cases here. */ | |
35e66bd1 | 2009 | if (class == 'e' && code == TRUTH_NOT_EXPR) |
c05a9b68 RS |
2010 | class = '1'; |
2011 | else if (class == 'e' | |
2012 | && (code == TRUTH_ANDIF_EXPR || code == TRUTH_ORIF_EXPR | |
2013 | || code == COMPOUND_EXPR)) | |
2014 | class = '2'; | |
2315a5db RS |
2015 | |
2016 | /* ??? Disable this since the SAVE_EXPR might already be in use outside | |
2017 | the expression. There may be no way to make this work, but it needs | |
2018 | to be looked at again for 2.6. */ | |
2019 | #if 0 | |
35e66bd1 RK |
2020 | else if (class == 'e' && code == SAVE_EXPR && SAVE_EXPR_RTL (arg) == 0) |
2021 | { | |
2022 | /* If we've already found a CVAL1 or CVAL2, this expression is | |
2023 | two complex to handle. */ | |
2024 | if (*cval1 || *cval2) | |
2025 | return 0; | |
2026 | ||
2027 | class = '1'; | |
2028 | *save_p = 1; | |
2029 | } | |
2315a5db | 2030 | #endif |
c05a9b68 RS |
2031 | |
2032 | switch (class) | |
2033 | { | |
2034 | case '1': | |
35e66bd1 | 2035 | return twoval_comparison_p (TREE_OPERAND (arg, 0), cval1, cval2, save_p); |
c05a9b68 RS |
2036 | |
2037 | case '2': | |
35e66bd1 RK |
2038 | return (twoval_comparison_p (TREE_OPERAND (arg, 0), cval1, cval2, save_p) |
2039 | && twoval_comparison_p (TREE_OPERAND (arg, 1), | |
2040 | cval1, cval2, save_p)); | |
c05a9b68 RS |
2041 | |
2042 | case 'c': | |
2043 | return 1; | |
2044 | ||
2045 | case 'e': | |
2046 | if (code == COND_EXPR) | |
35e66bd1 RK |
2047 | return (twoval_comparison_p (TREE_OPERAND (arg, 0), |
2048 | cval1, cval2, save_p) | |
2049 | && twoval_comparison_p (TREE_OPERAND (arg, 1), | |
2050 | cval1, cval2, save_p) | |
c05a9b68 | 2051 | && twoval_comparison_p (TREE_OPERAND (arg, 2), |
35e66bd1 | 2052 | cval1, cval2, save_p)); |
c05a9b68 RS |
2053 | return 0; |
2054 | ||
2055 | case '<': | |
2056 | /* First see if we can handle the first operand, then the second. For | |
2057 | the second operand, we know *CVAL1 can't be zero. It must be that | |
2058 | one side of the comparison is each of the values; test for the | |
2059 | case where this isn't true by failing if the two operands | |
2060 | are the same. */ | |
2061 | ||
2062 | if (operand_equal_p (TREE_OPERAND (arg, 0), | |
2063 | TREE_OPERAND (arg, 1), 0)) | |
2064 | return 0; | |
2065 | ||
2066 | if (*cval1 == 0) | |
2067 | *cval1 = TREE_OPERAND (arg, 0); | |
2068 | else if (operand_equal_p (*cval1, TREE_OPERAND (arg, 0), 0)) | |
2069 | ; | |
2070 | else if (*cval2 == 0) | |
2071 | *cval2 = TREE_OPERAND (arg, 0); | |
2072 | else if (operand_equal_p (*cval2, TREE_OPERAND (arg, 0), 0)) | |
2073 | ; | |
2074 | else | |
2075 | return 0; | |
2076 | ||
2077 | if (operand_equal_p (*cval1, TREE_OPERAND (arg, 1), 0)) | |
2078 | ; | |
2079 | else if (*cval2 == 0) | |
2080 | *cval2 = TREE_OPERAND (arg, 1); | |
2081 | else if (operand_equal_p (*cval2, TREE_OPERAND (arg, 1), 0)) | |
2082 | ; | |
2083 | else | |
2084 | return 0; | |
2085 | ||
2086 | return 1; | |
c05a9b68 | 2087 | |
e9a25f70 JL |
2088 | default: |
2089 | return 0; | |
2090 | } | |
c05a9b68 RS |
2091 | } |
2092 | \f | |
2093 | /* ARG is a tree that is known to contain just arithmetic operations and | |
2094 | comparisons. Evaluate the operations in the tree substituting NEW0 for | |
f72aed24 | 2095 | any occurrence of OLD0 as an operand of a comparison and likewise for |
c05a9b68 RS |
2096 | NEW1 and OLD1. */ |
2097 | ||
2098 | static tree | |
2099 | eval_subst (arg, old0, new0, old1, new1) | |
2100 | tree arg; | |
2101 | tree old0, new0, old1, new1; | |
2102 | { | |
2103 | tree type = TREE_TYPE (arg); | |
2104 | enum tree_code code = TREE_CODE (arg); | |
2105 | char class = TREE_CODE_CLASS (code); | |
2106 | ||
2107 | /* We can handle some of the 'e' cases here. */ | |
2108 | if (class == 'e' && code == TRUTH_NOT_EXPR) | |
2109 | class = '1'; | |
2110 | else if (class == 'e' | |
2111 | && (code == TRUTH_ANDIF_EXPR || code == TRUTH_ORIF_EXPR)) | |
2112 | class = '2'; | |
2113 | ||
2114 | switch (class) | |
2115 | { | |
2116 | case '1': | |
2117 | return fold (build1 (code, type, | |
2118 | eval_subst (TREE_OPERAND (arg, 0), | |
2119 | old0, new0, old1, new1))); | |
2120 | ||
2121 | case '2': | |
2122 | return fold (build (code, type, | |
2123 | eval_subst (TREE_OPERAND (arg, 0), | |
2124 | old0, new0, old1, new1), | |
2125 | eval_subst (TREE_OPERAND (arg, 1), | |
2126 | old0, new0, old1, new1))); | |
2127 | ||
2128 | case 'e': | |
2129 | switch (code) | |
2130 | { | |
2131 | case SAVE_EXPR: | |
2132 | return eval_subst (TREE_OPERAND (arg, 0), old0, new0, old1, new1); | |
2133 | ||
2134 | case COMPOUND_EXPR: | |
2135 | return eval_subst (TREE_OPERAND (arg, 1), old0, new0, old1, new1); | |
2136 | ||
2137 | case COND_EXPR: | |
2138 | return fold (build (code, type, | |
2139 | eval_subst (TREE_OPERAND (arg, 0), | |
2140 | old0, new0, old1, new1), | |
2141 | eval_subst (TREE_OPERAND (arg, 1), | |
2142 | old0, new0, old1, new1), | |
2143 | eval_subst (TREE_OPERAND (arg, 2), | |
2144 | old0, new0, old1, new1))); | |
e9a25f70 JL |
2145 | default: |
2146 | break; | |
c05a9b68 | 2147 | } |
e9a25f70 | 2148 | /* fall through (???) */ |
c05a9b68 RS |
2149 | |
2150 | case '<': | |
2151 | { | |
2152 | tree arg0 = TREE_OPERAND (arg, 0); | |
2153 | tree arg1 = TREE_OPERAND (arg, 1); | |
2154 | ||
2155 | /* We need to check both for exact equality and tree equality. The | |
2156 | former will be true if the operand has a side-effect. In that | |
2157 | case, we know the operand occurred exactly once. */ | |
2158 | ||
2159 | if (arg0 == old0 || operand_equal_p (arg0, old0, 0)) | |
2160 | arg0 = new0; | |
2161 | else if (arg0 == old1 || operand_equal_p (arg0, old1, 0)) | |
2162 | arg0 = new1; | |
2163 | ||
2164 | if (arg1 == old0 || operand_equal_p (arg1, old0, 0)) | |
2165 | arg1 = new0; | |
2166 | else if (arg1 == old1 || operand_equal_p (arg1, old1, 0)) | |
2167 | arg1 = new1; | |
2168 | ||
2169 | return fold (build (code, type, arg0, arg1)); | |
2170 | } | |
c05a9b68 | 2171 | |
e9a25f70 JL |
2172 | default: |
2173 | return arg; | |
2174 | } | |
c05a9b68 RS |
2175 | } |
2176 | \f | |
6d716ca8 RS |
2177 | /* Return a tree for the case when the result of an expression is RESULT |
2178 | converted to TYPE and OMITTED was previously an operand of the expression | |
2179 | but is now not needed (e.g., we folded OMITTED * 0). | |
2180 | ||
2181 | If OMITTED has side effects, we must evaluate it. Otherwise, just do | |
2182 | the conversion of RESULT to TYPE. */ | |
2183 | ||
2184 | static tree | |
2185 | omit_one_operand (type, result, omitted) | |
2186 | tree type, result, omitted; | |
2187 | { | |
2188 | tree t = convert (type, result); | |
2189 | ||
2190 | if (TREE_SIDE_EFFECTS (omitted)) | |
2191 | return build (COMPOUND_EXPR, type, omitted, t); | |
2192 | ||
d023bff9 | 2193 | return non_lvalue (t); |
6d716ca8 | 2194 | } |
4ab3cb65 RK |
2195 | |
2196 | /* Similar, but call pedantic_non_lvalue instead of non_lvalue. */ | |
2197 | ||
2198 | static tree | |
2199 | pedantic_omit_one_operand (type, result, omitted) | |
2200 | tree type, result, omitted; | |
2201 | { | |
2202 | tree t = convert (type, result); | |
2203 | ||
2204 | if (TREE_SIDE_EFFECTS (omitted)) | |
2205 | return build (COMPOUND_EXPR, type, omitted, t); | |
2206 | ||
2207 | return pedantic_non_lvalue (t); | |
2208 | } | |
2209 | ||
2210 | ||
6d716ca8 | 2211 | \f |
3f783329 RS |
2212 | /* Return a simplified tree node for the truth-negation of ARG. This |
2213 | never alters ARG itself. We assume that ARG is an operation that | |
6d716ca8 RS |
2214 | returns a truth value (0 or 1). */ |
2215 | ||
2216 | tree | |
2217 | invert_truthvalue (arg) | |
2218 | tree arg; | |
2219 | { | |
2220 | tree type = TREE_TYPE (arg); | |
c05a9b68 | 2221 | enum tree_code code = TREE_CODE (arg); |
6d716ca8 | 2222 | |
8ac1abdf JW |
2223 | if (code == ERROR_MARK) |
2224 | return arg; | |
2225 | ||
c05a9b68 RS |
2226 | /* If this is a comparison, we can simply invert it, except for |
2227 | floating-point non-equality comparisons, in which case we just | |
2228 | enclose a TRUTH_NOT_EXPR around what we have. */ | |
6d716ca8 | 2229 | |
c05a9b68 | 2230 | if (TREE_CODE_CLASS (code) == '<') |
6d716ca8 | 2231 | { |
7178e3af | 2232 | if (FLOAT_TYPE_P (TREE_TYPE (TREE_OPERAND (arg, 0))) |
a58bd508 | 2233 | && !flag_fast_math && code != NE_EXPR && code != EQ_EXPR) |
c05a9b68 RS |
2234 | return build1 (TRUTH_NOT_EXPR, type, arg); |
2235 | else | |
ca46db87 | 2236 | return build (invert_tree_comparison (code), type, |
3f783329 | 2237 | TREE_OPERAND (arg, 0), TREE_OPERAND (arg, 1)); |
c05a9b68 | 2238 | } |
6d716ca8 | 2239 | |
c05a9b68 RS |
2240 | switch (code) |
2241 | { | |
6d716ca8 RS |
2242 | case INTEGER_CST: |
2243 | return convert (type, build_int_2 (TREE_INT_CST_LOW (arg) == 0 | |
2244 | && TREE_INT_CST_HIGH (arg) == 0, 0)); | |
2245 | ||
2246 | case TRUTH_AND_EXPR: | |
2247 | return build (TRUTH_OR_EXPR, type, | |
2248 | invert_truthvalue (TREE_OPERAND (arg, 0)), | |
2249 | invert_truthvalue (TREE_OPERAND (arg, 1))); | |
2250 | ||
2251 | case TRUTH_OR_EXPR: | |
2252 | return build (TRUTH_AND_EXPR, type, | |
2253 | invert_truthvalue (TREE_OPERAND (arg, 0)), | |
2254 | invert_truthvalue (TREE_OPERAND (arg, 1))); | |
2255 | ||
772447c5 RK |
2256 | case TRUTH_XOR_EXPR: |
2257 | /* Here we can invert either operand. We invert the first operand | |
2258 | unless the second operand is a TRUTH_NOT_EXPR in which case our | |
2259 | result is the XOR of the first operand with the inside of the | |
2260 | negation of the second operand. */ | |
2261 | ||
2262 | if (TREE_CODE (TREE_OPERAND (arg, 1)) == TRUTH_NOT_EXPR) | |
2263 | return build (TRUTH_XOR_EXPR, type, TREE_OPERAND (arg, 0), | |
2264 | TREE_OPERAND (TREE_OPERAND (arg, 1), 0)); | |
2265 | else | |
2266 | return build (TRUTH_XOR_EXPR, type, | |
2267 | invert_truthvalue (TREE_OPERAND (arg, 0)), | |
2268 | TREE_OPERAND (arg, 1)); | |
2269 | ||
6d716ca8 RS |
2270 | case TRUTH_ANDIF_EXPR: |
2271 | return build (TRUTH_ORIF_EXPR, type, | |
2272 | invert_truthvalue (TREE_OPERAND (arg, 0)), | |
2273 | invert_truthvalue (TREE_OPERAND (arg, 1))); | |
2274 | ||
2275 | case TRUTH_ORIF_EXPR: | |
2276 | return build (TRUTH_ANDIF_EXPR, type, | |
2277 | invert_truthvalue (TREE_OPERAND (arg, 0)), | |
2278 | invert_truthvalue (TREE_OPERAND (arg, 1))); | |
2279 | ||
2280 | case TRUTH_NOT_EXPR: | |
2281 | return TREE_OPERAND (arg, 0); | |
2282 | ||
2283 | case COND_EXPR: | |
2284 | return build (COND_EXPR, type, TREE_OPERAND (arg, 0), | |
2285 | invert_truthvalue (TREE_OPERAND (arg, 1)), | |
2286 | invert_truthvalue (TREE_OPERAND (arg, 2))); | |
2287 | ||
ef9fe0da RK |
2288 | case COMPOUND_EXPR: |
2289 | return build (COMPOUND_EXPR, type, TREE_OPERAND (arg, 0), | |
2290 | invert_truthvalue (TREE_OPERAND (arg, 1))); | |
2291 | ||
6d716ca8 RS |
2292 | case NON_LVALUE_EXPR: |
2293 | return invert_truthvalue (TREE_OPERAND (arg, 0)); | |
2294 | ||
2295 | case NOP_EXPR: | |
2296 | case CONVERT_EXPR: | |
2297 | case FLOAT_EXPR: | |
2298 | return build1 (TREE_CODE (arg), type, | |
2299 | invert_truthvalue (TREE_OPERAND (arg, 0))); | |
2300 | ||
2301 | case BIT_AND_EXPR: | |
efc1a4d9 PB |
2302 | if (!integer_onep (TREE_OPERAND (arg, 1))) |
2303 | break; | |
6d716ca8 | 2304 | return build (EQ_EXPR, type, arg, convert (type, integer_zero_node)); |
6d716ca8 | 2305 | |
dfa90b42 RS |
2306 | case SAVE_EXPR: |
2307 | return build1 (TRUTH_NOT_EXPR, type, arg); | |
a25ee332 RK |
2308 | |
2309 | case CLEANUP_POINT_EXPR: | |
2310 | return build1 (CLEANUP_POINT_EXPR, type, | |
2311 | invert_truthvalue (TREE_OPERAND (arg, 0))); | |
e9a25f70 JL |
2312 | |
2313 | default: | |
2314 | break; | |
efc1a4d9 PB |
2315 | } |
2316 | if (TREE_CODE (TREE_TYPE (arg)) != BOOLEAN_TYPE) | |
dfa90b42 | 2317 | abort (); |
efc1a4d9 | 2318 | return build1 (TRUTH_NOT_EXPR, type, arg); |
6d716ca8 RS |
2319 | } |
2320 | ||
2321 | /* Given a bit-wise operation CODE applied to ARG0 and ARG1, see if both | |
2322 | operands are another bit-wise operation with a common input. If so, | |
2323 | distribute the bit operations to save an operation and possibly two if | |
2324 | constants are involved. For example, convert | |
2325 | (A | B) & (A | C) into A | (B & C) | |
2326 | Further simplification will occur if B and C are constants. | |
2327 | ||
2328 | If this optimization cannot be done, 0 will be returned. */ | |
2329 | ||
2330 | static tree | |
2331 | distribute_bit_expr (code, type, arg0, arg1) | |
2332 | enum tree_code code; | |
2333 | tree type; | |
2334 | tree arg0, arg1; | |
2335 | { | |
2336 | tree common; | |
2337 | tree left, right; | |
2338 | ||
2339 | if (TREE_CODE (arg0) != TREE_CODE (arg1) | |
2340 | || TREE_CODE (arg0) == code | |
fced8ba3 RS |
2341 | || (TREE_CODE (arg0) != BIT_AND_EXPR |
2342 | && TREE_CODE (arg0) != BIT_IOR_EXPR)) | |
6d716ca8 RS |
2343 | return 0; |
2344 | ||
2345 | if (operand_equal_p (TREE_OPERAND (arg0, 0), TREE_OPERAND (arg1, 0), 0)) | |
2346 | { | |
2347 | common = TREE_OPERAND (arg0, 0); | |
2348 | left = TREE_OPERAND (arg0, 1); | |
2349 | right = TREE_OPERAND (arg1, 1); | |
2350 | } | |
2351 | else if (operand_equal_p (TREE_OPERAND (arg0, 0), TREE_OPERAND (arg1, 1), 0)) | |
2352 | { | |
2353 | common = TREE_OPERAND (arg0, 0); | |
2354 | left = TREE_OPERAND (arg0, 1); | |
2355 | right = TREE_OPERAND (arg1, 0); | |
2356 | } | |
2357 | else if (operand_equal_p (TREE_OPERAND (arg0, 1), TREE_OPERAND (arg1, 0), 0)) | |
2358 | { | |
2359 | common = TREE_OPERAND (arg0, 1); | |
2360 | left = TREE_OPERAND (arg0, 0); | |
2361 | right = TREE_OPERAND (arg1, 1); | |
2362 | } | |
2363 | else if (operand_equal_p (TREE_OPERAND (arg0, 1), TREE_OPERAND (arg1, 1), 0)) | |
2364 | { | |
2365 | common = TREE_OPERAND (arg0, 1); | |
2366 | left = TREE_OPERAND (arg0, 0); | |
2367 | right = TREE_OPERAND (arg1, 0); | |
2368 | } | |
2369 | else | |
2370 | return 0; | |
2371 | ||
2372 | return fold (build (TREE_CODE (arg0), type, common, | |
2373 | fold (build (code, type, left, right)))); | |
2374 | } | |
2375 | \f | |
2376 | /* Return a BIT_FIELD_REF of type TYPE to refer to BITSIZE bits of INNER | |
2377 | starting at BITPOS. The field is unsigned if UNSIGNEDP is non-zero. */ | |
2378 | ||
2379 | static tree | |
2380 | make_bit_field_ref (inner, type, bitsize, bitpos, unsignedp) | |
2381 | tree inner; | |
2382 | tree type; | |
2383 | int bitsize, bitpos; | |
2384 | int unsignedp; | |
2385 | { | |
2386 | tree result = build (BIT_FIELD_REF, type, inner, | |
f8dac6eb | 2387 | size_int (bitsize), bitsize_int (bitpos, 0L)); |
6d716ca8 RS |
2388 | |
2389 | TREE_UNSIGNED (result) = unsignedp; | |
2390 | ||
2391 | return result; | |
2392 | } | |
2393 | ||
2394 | /* Optimize a bit-field compare. | |
2395 | ||
2396 | There are two cases: First is a compare against a constant and the | |
2397 | second is a comparison of two items where the fields are at the same | |
2398 | bit position relative to the start of a chunk (byte, halfword, word) | |
2399 | large enough to contain it. In these cases we can avoid the shift | |
2400 | implicit in bitfield extractions. | |
2401 | ||
2402 | For constants, we emit a compare of the shifted constant with the | |
2403 | BIT_AND_EXPR of a mask and a byte, halfword, or word of the operand being | |
2404 | compared. For two fields at the same position, we do the ANDs with the | |
2405 | similar mask and compare the result of the ANDs. | |
2406 | ||
2407 | CODE is the comparison code, known to be either NE_EXPR or EQ_EXPR. | |
2408 | COMPARE_TYPE is the type of the comparison, and LHS and RHS | |
2409 | are the left and right operands of the comparison, respectively. | |
2410 | ||
6dc42e49 | 2411 | If the optimization described above can be done, we return the resulting |
6d716ca8 RS |
2412 | tree. Otherwise we return zero. */ |
2413 | ||
2414 | static tree | |
2415 | optimize_bit_field_compare (code, compare_type, lhs, rhs) | |
2416 | enum tree_code code; | |
2417 | tree compare_type; | |
2418 | tree lhs, rhs; | |
2419 | { | |
2420 | int lbitpos, lbitsize, rbitpos, rbitsize; | |
4e86caed | 2421 | int lnbitpos, lnbitsize, rnbitpos = 0, rnbitsize = 0; |
6d716ca8 RS |
2422 | tree type = TREE_TYPE (lhs); |
2423 | tree signed_type, unsigned_type; | |
2424 | int const_p = TREE_CODE (rhs) == INTEGER_CST; | |
4e86caed | 2425 | enum machine_mode lmode, rmode, lnmode, rnmode = VOIDmode; |
6d716ca8 RS |
2426 | int lunsignedp, runsignedp; |
2427 | int lvolatilep = 0, rvolatilep = 0; | |
23bd99ae | 2428 | int alignment; |
4e86caed | 2429 | tree linner, rinner = NULL_TREE; |
6d716ca8 | 2430 | tree mask; |
f1e60ec6 | 2431 | tree offset; |
6d716ca8 RS |
2432 | |
2433 | /* Get all the information about the extractions being done. If the bit size | |
2434 | if the same as the size of the underlying object, we aren't doing an | |
2435 | extraction at all and so can do nothing. */ | |
f1e60ec6 | 2436 | linner = get_inner_reference (lhs, &lbitsize, &lbitpos, &offset, &lmode, |
23bd99ae | 2437 | &lunsignedp, &lvolatilep, &alignment); |
9f5e873c | 2438 | if (linner == lhs || lbitsize == GET_MODE_BITSIZE (lmode) || lbitsize < 0 |
f1e60ec6 | 2439 | || offset != 0) |
6d716ca8 RS |
2440 | return 0; |
2441 | ||
2442 | if (!const_p) | |
2443 | { | |
2444 | /* If this is not a constant, we can only do something if bit positions, | |
2445 | sizes, and signedness are the same. */ | |
23bd99ae RK |
2446 | rinner = get_inner_reference (rhs, &rbitsize, &rbitpos, &offset, &rmode, |
2447 | &runsignedp, &rvolatilep, &alignment); | |
6d716ca8 | 2448 | |
9f5e873c | 2449 | if (rinner == rhs || lbitpos != rbitpos || lbitsize != rbitsize |
f1e60ec6 | 2450 | || lunsignedp != runsignedp || offset != 0) |
6d716ca8 RS |
2451 | return 0; |
2452 | } | |
2453 | ||
2454 | /* See if we can find a mode to refer to this field. We should be able to, | |
2455 | but fail if we can't. */ | |
2456 | lnmode = get_best_mode (lbitsize, lbitpos, | |
2457 | TYPE_ALIGN (TREE_TYPE (linner)), word_mode, | |
2458 | lvolatilep); | |
2459 | if (lnmode == VOIDmode) | |
2460 | return 0; | |
2461 | ||
2462 | /* Set signed and unsigned types of the precision of this mode for the | |
2463 | shifts below. */ | |
2464 | signed_type = type_for_mode (lnmode, 0); | |
2465 | unsigned_type = type_for_mode (lnmode, 1); | |
2466 | ||
2467 | if (! const_p) | |
2468 | { | |
2469 | rnmode = get_best_mode (rbitsize, rbitpos, | |
2470 | TYPE_ALIGN (TREE_TYPE (rinner)), word_mode, | |
2471 | rvolatilep); | |
2472 | if (rnmode == VOIDmode) | |
2473 | return 0; | |
2474 | } | |
2475 | ||
2476 | /* Compute the bit position and size for the new reference and our offset | |
2477 | within it. If the new reference is the same size as the original, we | |
2478 | won't optimize anything, so return zero. */ | |
2479 | lnbitsize = GET_MODE_BITSIZE (lnmode); | |
2480 | lnbitpos = lbitpos & ~ (lnbitsize - 1); | |
2481 | lbitpos -= lnbitpos; | |
2482 | if (lnbitsize == lbitsize) | |
2483 | return 0; | |
2484 | ||
2485 | if (! const_p) | |
2486 | { | |
2487 | rnbitsize = GET_MODE_BITSIZE (rnmode); | |
2488 | rnbitpos = rbitpos & ~ (rnbitsize - 1); | |
2489 | rbitpos -= rnbitpos; | |
2490 | if (rnbitsize == rbitsize) | |
2491 | return 0; | |
2492 | } | |
2493 | ||
f76b9db2 ILT |
2494 | if (BYTES_BIG_ENDIAN) |
2495 | lbitpos = lnbitsize - lbitsize - lbitpos; | |
6d716ca8 RS |
2496 | |
2497 | /* Make the mask to be used against the extracted field. */ | |
13af526d RS |
2498 | mask = build_int_2 (~0, ~0); |
2499 | TREE_TYPE (mask) = unsigned_type; | |
aa830baf | 2500 | force_fit_type (mask, 0); |
13af526d | 2501 | mask = convert (unsigned_type, mask); |
91d33e36 | 2502 | mask = const_binop (LSHIFT_EXPR, mask, size_int (lnbitsize - lbitsize), 0); |
6d716ca8 | 2503 | mask = const_binop (RSHIFT_EXPR, mask, |
91d33e36 | 2504 | size_int (lnbitsize - lbitsize - lbitpos), 0); |
6d716ca8 RS |
2505 | |
2506 | if (! const_p) | |
2507 | /* If not comparing with constant, just rework the comparison | |
2508 | and return. */ | |
2509 | return build (code, compare_type, | |
c0b9d4c8 RK |
2510 | build (BIT_AND_EXPR, unsigned_type, |
2511 | make_bit_field_ref (linner, unsigned_type, | |
2512 | lnbitsize, lnbitpos, 1), | |
6d716ca8 | 2513 | mask), |
c0b9d4c8 RK |
2514 | build (BIT_AND_EXPR, unsigned_type, |
2515 | make_bit_field_ref (rinner, unsigned_type, | |
2516 | rnbitsize, rnbitpos, 1), | |
6d716ca8 RS |
2517 | mask)); |
2518 | ||
2519 | /* Otherwise, we are handling the constant case. See if the constant is too | |
2520 | big for the field. Warn and return a tree of for 0 (false) if so. We do | |
2521 | this not only for its own sake, but to avoid having to test for this | |
2522 | error case below. If we didn't, we might generate wrong code. | |
2523 | ||
2524 | For unsigned fields, the constant shifted right by the field length should | |
2525 | be all zero. For signed fields, the high-order bits should agree with | |
2526 | the sign bit. */ | |
2527 | ||
2528 | if (lunsignedp) | |
2529 | { | |
2530 | if (! integer_zerop (const_binop (RSHIFT_EXPR, | |
2531 | convert (unsigned_type, rhs), | |
91d33e36 | 2532 | size_int (lbitsize), 0))) |
6d716ca8 RS |
2533 | { |
2534 | warning ("comparison is always %s due to width of bitfield", | |
2535 | code == NE_EXPR ? "one" : "zero"); | |
2536 | return convert (compare_type, | |
2537 | (code == NE_EXPR | |
2538 | ? integer_one_node : integer_zero_node)); | |
2539 | } | |
2540 | } | |
2541 | else | |
2542 | { | |
2543 | tree tem = const_binop (RSHIFT_EXPR, convert (signed_type, rhs), | |
91d33e36 | 2544 | size_int (lbitsize - 1), 0); |
6d716ca8 RS |
2545 | if (! integer_zerop (tem) && ! integer_all_onesp (tem)) |
2546 | { | |
2547 | warning ("comparison is always %s due to width of bitfield", | |
2548 | code == NE_EXPR ? "one" : "zero"); | |
2549 | return convert (compare_type, | |
2550 | (code == NE_EXPR | |
2551 | ? integer_one_node : integer_zero_node)); | |
2552 | } | |
2553 | } | |
2554 | ||
2555 | /* Single-bit compares should always be against zero. */ | |
2556 | if (lbitsize == 1 && ! integer_zerop (rhs)) | |
2557 | { | |
2558 | code = code == EQ_EXPR ? NE_EXPR : EQ_EXPR; | |
2559 | rhs = convert (type, integer_zero_node); | |
2560 | } | |
2561 | ||
2562 | /* Make a new bitfield reference, shift the constant over the | |
2563 | appropriate number of bits and mask it with the computed mask | |
2564 | (in case this was a signed field). If we changed it, make a new one. */ | |
c0b9d4c8 | 2565 | lhs = make_bit_field_ref (linner, unsigned_type, lnbitsize, lnbitpos, 1); |
9db73acb RK |
2566 | if (lvolatilep) |
2567 | { | |
2568 | TREE_SIDE_EFFECTS (lhs) = 1; | |
2569 | TREE_THIS_VOLATILE (lhs) = 1; | |
2570 | } | |
6d716ca8 | 2571 | |
c0b9d4c8 RK |
2572 | rhs = fold (const_binop (BIT_AND_EXPR, |
2573 | const_binop (LSHIFT_EXPR, | |
2574 | convert (unsigned_type, rhs), | |
194c082f | 2575 | size_int (lbitpos), 0), |
91d33e36 | 2576 | mask, 0)); |
6d716ca8 RS |
2577 | |
2578 | return build (code, compare_type, | |
c0b9d4c8 | 2579 | build (BIT_AND_EXPR, unsigned_type, lhs, mask), |
6d716ca8 RS |
2580 | rhs); |
2581 | } | |
2582 | \f | |
b2215d83 | 2583 | /* Subroutine for fold_truthop: decode a field reference. |
6d716ca8 RS |
2584 | |
2585 | If EXP is a comparison reference, we return the innermost reference. | |
2586 | ||
2587 | *PBITSIZE is set to the number of bits in the reference, *PBITPOS is | |
2588 | set to the starting bit number. | |
2589 | ||
2590 | If the innermost field can be completely contained in a mode-sized | |
2591 | unit, *PMODE is set to that mode. Otherwise, it is set to VOIDmode. | |
2592 | ||
2593 | *PVOLATILEP is set to 1 if the any expression encountered is volatile; | |
2594 | otherwise it is not changed. | |
2595 | ||
2596 | *PUNSIGNEDP is set to the signedness of the field. | |
2597 | ||
2598 | *PMASK is set to the mask used. This is either contained in a | |
2599 | BIT_AND_EXPR or derived from the width of the field. | |
2600 | ||
38e01259 | 2601 | *PAND_MASK is set to the mask found in a BIT_AND_EXPR, if any. |
d4453ee5 | 2602 | |
6d716ca8 RS |
2603 | Return 0 if this is not a component reference or is one that we can't |
2604 | do anything with. */ | |
2605 | ||
2606 | static tree | |
2607 | decode_field_reference (exp, pbitsize, pbitpos, pmode, punsignedp, | |
d4453ee5 | 2608 | pvolatilep, pmask, pand_mask) |
6d716ca8 RS |
2609 | tree exp; |
2610 | int *pbitsize, *pbitpos; | |
2611 | enum machine_mode *pmode; | |
2612 | int *punsignedp, *pvolatilep; | |
2613 | tree *pmask; | |
d4453ee5 | 2614 | tree *pand_mask; |
6d716ca8 | 2615 | { |
6d9f1f5f RK |
2616 | tree and_mask = 0; |
2617 | tree mask, inner, offset; | |
2618 | tree unsigned_type; | |
2619 | int precision; | |
23bd99ae | 2620 | int alignment; |
6d716ca8 | 2621 | |
772ae9f0 RK |
2622 | /* All the optimizations using this function assume integer fields. |
2623 | There are problems with FP fields since the type_for_size call | |
2624 | below can fail for, e.g., XFmode. */ | |
2625 | if (! INTEGRAL_TYPE_P (TREE_TYPE (exp))) | |
2626 | return 0; | |
2627 | ||
6d716ca8 RS |
2628 | STRIP_NOPS (exp); |
2629 | ||
2630 | if (TREE_CODE (exp) == BIT_AND_EXPR) | |
2631 | { | |
6d9f1f5f | 2632 | and_mask = TREE_OPERAND (exp, 1); |
6d716ca8 | 2633 | exp = TREE_OPERAND (exp, 0); |
6d9f1f5f RK |
2634 | STRIP_NOPS (exp); STRIP_NOPS (and_mask); |
2635 | if (TREE_CODE (and_mask) != INTEGER_CST) | |
6d716ca8 RS |
2636 | return 0; |
2637 | } | |
2638 | ||
6d716ca8 | 2639 | |
f1e60ec6 | 2640 | inner = get_inner_reference (exp, pbitsize, pbitpos, &offset, pmode, |
23bd99ae | 2641 | punsignedp, pvolatilep, &alignment); |
02103577 RK |
2642 | if ((inner == exp && and_mask == 0) |
2643 | || *pbitsize < 0 || offset != 0) | |
c05a9b68 | 2644 | return 0; |
6d716ca8 | 2645 | |
6d9f1f5f RK |
2646 | /* Compute the mask to access the bitfield. */ |
2647 | unsigned_type = type_for_size (*pbitsize, 1); | |
2648 | precision = TYPE_PRECISION (unsigned_type); | |
2649 | ||
2650 | mask = build_int_2 (~0, ~0); | |
2651 | TREE_TYPE (mask) = unsigned_type; | |
2652 | force_fit_type (mask, 0); | |
2653 | mask = const_binop (LSHIFT_EXPR, mask, size_int (precision - *pbitsize), 0); | |
2654 | mask = const_binop (RSHIFT_EXPR, mask, size_int (precision - *pbitsize), 0); | |
2655 | ||
2656 | /* Merge it with the mask we found in the BIT_AND_EXPR, if any. */ | |
2657 | if (and_mask != 0) | |
2658 | mask = fold (build (BIT_AND_EXPR, unsigned_type, | |
2659 | convert (unsigned_type, and_mask), mask)); | |
6d716ca8 RS |
2660 | |
2661 | *pmask = mask; | |
d4453ee5 | 2662 | *pand_mask = and_mask; |
6d716ca8 RS |
2663 | return inner; |
2664 | } | |
2665 | ||
6dc42e49 | 2666 | /* Return non-zero if MASK represents a mask of SIZE ones in the low-order |
6d716ca8 RS |
2667 | bit positions. */ |
2668 | ||
2669 | static int | |
2670 | all_ones_mask_p (mask, size) | |
2671 | tree mask; | |
2672 | int size; | |
2673 | { | |
2674 | tree type = TREE_TYPE (mask); | |
2675 | int precision = TYPE_PRECISION (type); | |
13af526d | 2676 | tree tmask; |
6d716ca8 | 2677 | |
13af526d RS |
2678 | tmask = build_int_2 (~0, ~0); |
2679 | TREE_TYPE (tmask) = signed_type (type); | |
aa830baf | 2680 | force_fit_type (tmask, 0); |
6d716ca8 | 2681 | return |
02103577 RK |
2682 | tree_int_cst_equal (mask, |
2683 | const_binop (RSHIFT_EXPR, | |
2684 | const_binop (LSHIFT_EXPR, tmask, | |
2685 | size_int (precision - size), | |
2686 | 0), | |
2687 | size_int (precision - size), 0)); | |
6d716ca8 | 2688 | } |
b2215d83 TW |
2689 | |
2690 | /* Subroutine for fold_truthop: determine if an operand is simple enough | |
2691 | to be evaluated unconditionally. */ | |
2692 | ||
b2215d83 TW |
2693 | static int |
2694 | simple_operand_p (exp) | |
2695 | tree exp; | |
2696 | { | |
2697 | /* Strip any conversions that don't change the machine mode. */ | |
2698 | while ((TREE_CODE (exp) == NOP_EXPR | |
2699 | || TREE_CODE (exp) == CONVERT_EXPR) | |
2700 | && (TYPE_MODE (TREE_TYPE (exp)) | |
2701 | == TYPE_MODE (TREE_TYPE (TREE_OPERAND (exp, 0))))) | |
2702 | exp = TREE_OPERAND (exp, 0); | |
2703 | ||
2704 | return (TREE_CODE_CLASS (TREE_CODE (exp)) == 'c' | |
2705 | || (TREE_CODE_CLASS (TREE_CODE (exp)) == 'd' | |
2706 | && ! TREE_ADDRESSABLE (exp) | |
2707 | && ! TREE_THIS_VOLATILE (exp) | |
8227896c TW |
2708 | && ! DECL_NONLOCAL (exp) |
2709 | /* Don't regard global variables as simple. They may be | |
2710 | allocated in ways unknown to the compiler (shared memory, | |
2711 | #pragma weak, etc). */ | |
2712 | && ! TREE_PUBLIC (exp) | |
2713 | && ! DECL_EXTERNAL (exp) | |
2714 | /* Loading a static variable is unduly expensive, but global | |
2715 | registers aren't expensive. */ | |
2716 | && (! TREE_STATIC (exp) || DECL_REGISTER (exp)))); | |
b2215d83 | 2717 | } |
6d716ca8 | 2718 | \f |
ebde8a27 RK |
2719 | /* The following functions are subroutines to fold_range_test and allow it to |
2720 | try to change a logical combination of comparisons into a range test. | |
2721 | ||
2722 | For example, both | |
2723 | X == 2 && X == 3 && X == 4 && X == 5 | |
2724 | and | |
2725 | X >= 2 && X <= 5 | |
2726 | are converted to | |
2727 | (unsigned) (X - 2) <= 3 | |
2728 | ||
956d6950 | 2729 | We describe each set of comparisons as being either inside or outside |
ebde8a27 RK |
2730 | a range, using a variable named like IN_P, and then describe the |
2731 | range with a lower and upper bound. If one of the bounds is omitted, | |
2732 | it represents either the highest or lowest value of the type. | |
2733 | ||
2734 | In the comments below, we represent a range by two numbers in brackets | |
956d6950 | 2735 | preceded by a "+" to designate being inside that range, or a "-" to |
ebde8a27 RK |
2736 | designate being outside that range, so the condition can be inverted by |
2737 | flipping the prefix. An omitted bound is represented by a "-". For | |
2738 | example, "- [-, 10]" means being outside the range starting at the lowest | |
2739 | possible value and ending at 10, in other words, being greater than 10. | |
2740 | The range "+ [-, -]" is always true and hence the range "- [-, -]" is | |
2741 | always false. | |
2742 | ||
2743 | We set up things so that the missing bounds are handled in a consistent | |
2744 | manner so neither a missing bound nor "true" and "false" need to be | |
2745 | handled using a special case. */ | |
2746 | ||
2747 | /* Return the result of applying CODE to ARG0 and ARG1, but handle the case | |
2748 | of ARG0 and/or ARG1 being omitted, meaning an unlimited range. UPPER0_P | |
2749 | and UPPER1_P are nonzero if the respective argument is an upper bound | |
2750 | and zero for a lower. TYPE, if nonzero, is the type of the result; it | |
2751 | must be specified for a comparison. ARG1 will be converted to ARG0's | |
2752 | type if both are specified. */ | |
ef659ec0 | 2753 | |
ebde8a27 RK |
2754 | static tree |
2755 | range_binop (code, type, arg0, upper0_p, arg1, upper1_p) | |
2756 | enum tree_code code; | |
2757 | tree type; | |
2758 | tree arg0, arg1; | |
2759 | int upper0_p, upper1_p; | |
2760 | { | |
27bae8e5 | 2761 | tree tem; |
ebde8a27 RK |
2762 | int result; |
2763 | int sgn0, sgn1; | |
ef659ec0 | 2764 | |
ebde8a27 RK |
2765 | /* If neither arg represents infinity, do the normal operation. |
2766 | Else, if not a comparison, return infinity. Else handle the special | |
2767 | comparison rules. Note that most of the cases below won't occur, but | |
2768 | are handled for consistency. */ | |
ef659ec0 | 2769 | |
ebde8a27 | 2770 | if (arg0 != 0 && arg1 != 0) |
27bae8e5 RK |
2771 | { |
2772 | tem = fold (build (code, type != 0 ? type : TREE_TYPE (arg0), | |
2773 | arg0, convert (TREE_TYPE (arg0), arg1))); | |
2774 | STRIP_NOPS (tem); | |
2775 | return TREE_CODE (tem) == INTEGER_CST ? tem : 0; | |
2776 | } | |
ef659ec0 | 2777 | |
ebde8a27 RK |
2778 | if (TREE_CODE_CLASS (code) != '<') |
2779 | return 0; | |
2780 | ||
2781 | /* Set SGN[01] to -1 if ARG[01] is a lower bound, 1 for upper, and 0 | |
2782 | for neither. Then compute our result treating them as never equal | |
2783 | and comparing bounds to non-bounds as above. */ | |
2784 | sgn0 = arg0 != 0 ? 0 : (upper0_p ? 1 : -1); | |
4e644c93 | 2785 | sgn1 = arg1 != 0 ? 0 : (upper1_p ? 1 : -1); |
ebde8a27 RK |
2786 | switch (code) |
2787 | { | |
2788 | case EQ_EXPR: case NE_EXPR: | |
2789 | result = (code == NE_EXPR); | |
2790 | break; | |
2791 | case LT_EXPR: case LE_EXPR: | |
2792 | result = sgn0 < sgn1; | |
2793 | break; | |
2794 | case GT_EXPR: case GE_EXPR: | |
2795 | result = sgn0 > sgn1; | |
2796 | break; | |
e9a25f70 JL |
2797 | default: |
2798 | abort (); | |
ebde8a27 RK |
2799 | } |
2800 | ||
2801 | return convert (type, result ? integer_one_node : integer_zero_node); | |
2802 | } | |
2803 | \f | |
2804 | /* Given EXP, a logical expression, set the range it is testing into | |
2805 | variables denoted by PIN_P, PLOW, and PHIGH. Return the expression | |
2806 | actually being tested. *PLOW and *PHIGH will have be made the same type | |
2807 | as the returned expression. If EXP is not a comparison, we will most | |
2808 | likely not be returning a useful value and range. */ | |
ef659ec0 | 2809 | |
6dc7571d | 2810 | static tree |
ebde8a27 RK |
2811 | make_range (exp, pin_p, plow, phigh) |
2812 | tree exp; | |
2813 | int *pin_p; | |
2814 | tree *plow, *phigh; | |
ef659ec0 | 2815 | { |
ebde8a27 | 2816 | enum tree_code code; |
4e86caed | 2817 | tree arg0, arg1, type = NULL_TREE; |
7d12cee1 | 2818 | tree orig_type = NULL_TREE; |
ebde8a27 RK |
2819 | int in_p, n_in_p; |
2820 | tree low, high, n_low, n_high; | |
ef659ec0 | 2821 | |
ebde8a27 RK |
2822 | /* Start with simply saying "EXP != 0" and then look at the code of EXP |
2823 | and see if we can refine the range. Some of the cases below may not | |
2824 | happen, but it doesn't seem worth worrying about this. We "continue" | |
2825 | the outer loop when we've changed something; otherwise we "break" | |
2826 | the switch, which will "break" the while. */ | |
ef659ec0 | 2827 | |
ebde8a27 RK |
2828 | in_p = 0, low = high = convert (TREE_TYPE (exp), integer_zero_node); |
2829 | ||
2830 | while (1) | |
ef659ec0 | 2831 | { |
ebde8a27 | 2832 | code = TREE_CODE (exp); |
30d68b86 MM |
2833 | |
2834 | if (IS_EXPR_CODE_CLASS (TREE_CODE_CLASS (code))) | |
2835 | { | |
2836 | arg0 = TREE_OPERAND (exp, 0); | |
2837 | if (TREE_CODE_CLASS (code) == '<' | |
2838 | || TREE_CODE_CLASS (code) == '1' | |
2839 | || TREE_CODE_CLASS (code) == '2') | |
2840 | type = TREE_TYPE (arg0); | |
2841 | if (TREE_CODE_CLASS (code) == '2' | |
2842 | || TREE_CODE_CLASS (code) == '<' | |
2843 | || (TREE_CODE_CLASS (code) == 'e' | |
2844 | && tree_code_length[(int) code] > 1)) | |
2845 | arg1 = TREE_OPERAND (exp, 1); | |
2846 | } | |
ef659ec0 | 2847 | |
ebde8a27 RK |
2848 | switch (code) |
2849 | { | |
2850 | case TRUTH_NOT_EXPR: | |
2851 | in_p = ! in_p, exp = arg0; | |
2852 | continue; | |
2853 | ||
2854 | case EQ_EXPR: case NE_EXPR: | |
2855 | case LT_EXPR: case LE_EXPR: case GE_EXPR: case GT_EXPR: | |
2856 | /* We can only do something if the range is testing for zero | |
2857 | and if the second operand is an integer constant. Note that | |
2858 | saying something is "in" the range we make is done by | |
2859 | complementing IN_P since it will set in the initial case of | |
2860 | being not equal to zero; "out" is leaving it alone. */ | |
2861 | if (low == 0 || high == 0 | |
2862 | || ! integer_zerop (low) || ! integer_zerop (high) | |
2863 | || TREE_CODE (arg1) != INTEGER_CST) | |
2864 | break; | |
ef659ec0 | 2865 | |
ebde8a27 RK |
2866 | switch (code) |
2867 | { | |
2868 | case NE_EXPR: /* - [c, c] */ | |
2869 | low = high = arg1; | |
2870 | break; | |
2871 | case EQ_EXPR: /* + [c, c] */ | |
2872 | in_p = ! in_p, low = high = arg1; | |
2873 | break; | |
2874 | case GT_EXPR: /* - [-, c] */ | |
2875 | low = 0, high = arg1; | |
2876 | break; | |
2877 | case GE_EXPR: /* + [c, -] */ | |
2878 | in_p = ! in_p, low = arg1, high = 0; | |
2879 | break; | |
2880 | case LT_EXPR: /* - [c, -] */ | |
2881 | low = arg1, high = 0; | |
2882 | break; | |
2883 | case LE_EXPR: /* + [-, c] */ | |
2884 | in_p = ! in_p, low = 0, high = arg1; | |
2885 | break; | |
e9a25f70 JL |
2886 | default: |
2887 | abort (); | |
ebde8a27 | 2888 | } |
ef659ec0 | 2889 | |
ebde8a27 | 2890 | exp = arg0; |
ef659ec0 | 2891 | |
7f423031 | 2892 | /* If this is an unsigned comparison, we also know that EXP is |
0e1c7fc7 RK |
2893 | greater than or equal to zero. We base the range tests we make |
2894 | on that fact, so we record it here so we can parse existing | |
2895 | range tests. */ | |
7f423031 | 2896 | if (TREE_UNSIGNED (type) && (low == 0 || high == 0)) |
ebde8a27 RK |
2897 | { |
2898 | if (! merge_ranges (&n_in_p, &n_low, &n_high, in_p, low, high, | |
2899 | 1, convert (type, integer_zero_node), | |
0e1c7fc7 | 2900 | NULL_TREE)) |
ebde8a27 | 2901 | break; |
ef659ec0 | 2902 | |
ebde8a27 | 2903 | in_p = n_in_p, low = n_low, high = n_high; |
0e1c7fc7 RK |
2904 | |
2905 | /* If the high bound is missing, reverse the range so it | |
2906 | goes from zero to the low bound minus 1. */ | |
2907 | if (high == 0) | |
2908 | { | |
2909 | in_p = ! in_p; | |
2910 | high = range_binop (MINUS_EXPR, NULL_TREE, low, 0, | |
2911 | integer_one_node, 0); | |
2912 | low = convert (type, integer_zero_node); | |
2913 | } | |
ebde8a27 RK |
2914 | } |
2915 | continue; | |
2916 | ||
2917 | case NEGATE_EXPR: | |
2918 | /* (-x) IN [a,b] -> x in [-b, -a] */ | |
2919 | n_low = range_binop (MINUS_EXPR, type, | |
2920 | convert (type, integer_zero_node), 0, high, 1); | |
2921 | n_high = range_binop (MINUS_EXPR, type, | |
2922 | convert (type, integer_zero_node), 0, low, 0); | |
2923 | low = n_low, high = n_high; | |
2924 | exp = arg0; | |
2925 | continue; | |
2926 | ||
2927 | case BIT_NOT_EXPR: | |
2928 | /* ~ X -> -X - 1 */ | |
2929 | exp = build (MINUS_EXPR, type, build1 (NEGATE_EXPR, type, arg0), | |
27bae8e5 | 2930 | convert (type, integer_one_node)); |
ebde8a27 RK |
2931 | continue; |
2932 | ||
2933 | case PLUS_EXPR: case MINUS_EXPR: | |
2934 | if (TREE_CODE (arg1) != INTEGER_CST) | |
2935 | break; | |
2936 | ||
2937 | /* If EXP is signed, any overflow in the computation is undefined, | |
2938 | so we don't worry about it so long as our computations on | |
2939 | the bounds don't overflow. For unsigned, overflow is defined | |
2940 | and this is exactly the right thing. */ | |
2941 | n_low = range_binop (code == MINUS_EXPR ? PLUS_EXPR : MINUS_EXPR, | |
2942 | type, low, 0, arg1, 0); | |
2943 | n_high = range_binop (code == MINUS_EXPR ? PLUS_EXPR : MINUS_EXPR, | |
2944 | type, high, 1, arg1, 0); | |
2945 | if ((n_low != 0 && TREE_OVERFLOW (n_low)) | |
2946 | || (n_high != 0 && TREE_OVERFLOW (n_high))) | |
2947 | break; | |
2948 | ||
3c00684e JL |
2949 | /* Check for an unsigned range which has wrapped around the maximum |
2950 | value thus making n_high < n_low, and normalize it. */ | |
5a9d82a6 | 2951 | if (n_low && n_high && tree_int_cst_lt (n_high, n_low)) |
3c00684e JL |
2952 | { |
2953 | low = range_binop (PLUS_EXPR, type, n_high, 0, | |
0e1c7fc7 | 2954 | integer_one_node, 0); |
3c00684e | 2955 | high = range_binop (MINUS_EXPR, type, n_low, 0, |
0e1c7fc7 | 2956 | integer_one_node, 0); |
3c00684e JL |
2957 | in_p = ! in_p; |
2958 | } | |
5a9d82a6 JW |
2959 | else |
2960 | low = n_low, high = n_high; | |
27bae8e5 | 2961 | |
ebde8a27 RK |
2962 | exp = arg0; |
2963 | continue; | |
2964 | ||
2965 | case NOP_EXPR: case NON_LVALUE_EXPR: case CONVERT_EXPR: | |
7d12cee1 JL |
2966 | if (orig_type == NULL_TREE) |
2967 | orig_type = type; | |
2968 | if (TYPE_PRECISION (type) > TYPE_PRECISION (orig_type)) | |
2969 | break; | |
2970 | ||
ebde8a27 RK |
2971 | if (! INTEGRAL_TYPE_P (type) |
2972 | || (low != 0 && ! int_fits_type_p (low, type)) | |
2973 | || (high != 0 && ! int_fits_type_p (high, type))) | |
2974 | break; | |
2975 | ||
ce2157a1 | 2976 | n_low = low, n_high = high; |
ebde8a27 | 2977 | |
ce2157a1 JL |
2978 | if (n_low != 0) |
2979 | n_low = convert (type, n_low); | |
2980 | ||
2981 | if (n_high != 0) | |
2982 | n_high = convert (type, n_high); | |
2983 | ||
2984 | /* If we're converting from an unsigned to a signed type, | |
2985 | we will be doing the comparison as unsigned. The tests above | |
2986 | have already verified that LOW and HIGH are both positive. | |
2987 | ||
2988 | So we have to make sure that the original unsigned value will | |
2989 | be interpreted as positive. */ | |
2990 | if (TREE_UNSIGNED (type) && ! TREE_UNSIGNED (TREE_TYPE (exp))) | |
2991 | { | |
2992 | tree equiv_type = type_for_mode (TYPE_MODE (type), 1); | |
e1ee5cdc RH |
2993 | tree high_positive; |
2994 | ||
2995 | /* A range without an upper bound is, naturally, unbounded. | |
2996 | Since convert would have cropped a very large value, use | |
2997 | the max value for the destination type. */ | |
2998 | ||
2999 | high_positive = TYPE_MAX_VALUE (equiv_type); | |
3000 | if (!high_positive) | |
3001 | { | |
3002 | high_positive = TYPE_MAX_VALUE (type); | |
3003 | if (!high_positive) | |
3004 | abort(); | |
3005 | } | |
3006 | high_positive = fold (build (RSHIFT_EXPR, type, | |
3007 | convert (type, high_positive), | |
3008 | convert (type, integer_one_node))); | |
ce2157a1 JL |
3009 | |
3010 | /* If the low bound is specified, "and" the range with the | |
3011 | range for which the original unsigned value will be | |
3012 | positive. */ | |
3013 | if (low != 0) | |
3014 | { | |
3015 | if (! merge_ranges (&n_in_p, &n_low, &n_high, | |
3016 | 1, n_low, n_high, | |
3017 | 1, convert (type, integer_zero_node), | |
3018 | high_positive)) | |
3019 | break; | |
3020 | ||
3021 | in_p = (n_in_p == in_p); | |
3022 | } | |
3023 | else | |
3024 | { | |
3025 | /* Otherwise, "or" the range with the range of the input | |
3026 | that will be interpreted as negative. */ | |
3027 | if (! merge_ranges (&n_in_p, &n_low, &n_high, | |
3028 | 0, n_low, n_high, | |
3029 | 1, convert (type, integer_zero_node), | |
3030 | high_positive)) | |
3031 | break; | |
3032 | ||
3033 | in_p = (in_p != n_in_p); | |
3034 | } | |
3035 | } | |
ebde8a27 RK |
3036 | |
3037 | exp = arg0; | |
ce2157a1 | 3038 | low = n_low, high = n_high; |
ebde8a27 | 3039 | continue; |
ce2157a1 JL |
3040 | |
3041 | default: | |
3042 | break; | |
ef659ec0 | 3043 | } |
ebde8a27 RK |
3044 | |
3045 | break; | |
ef659ec0 | 3046 | } |
ebde8a27 | 3047 | |
80906567 RK |
3048 | /* If EXP is a constant, we can evaluate whether this is true or false. */ |
3049 | if (TREE_CODE (exp) == INTEGER_CST) | |
3050 | { | |
3051 | in_p = in_p == (integer_onep (range_binop (GE_EXPR, integer_type_node, | |
3052 | exp, 0, low, 0)) | |
3053 | && integer_onep (range_binop (LE_EXPR, integer_type_node, | |
3054 | exp, 1, high, 1))); | |
3055 | low = high = 0; | |
3056 | exp = 0; | |
3057 | } | |
3058 | ||
ebde8a27 RK |
3059 | *pin_p = in_p, *plow = low, *phigh = high; |
3060 | return exp; | |
3061 | } | |
3062 | \f | |
3063 | /* Given a range, LOW, HIGH, and IN_P, an expression, EXP, and a result | |
3064 | type, TYPE, return an expression to test if EXP is in (or out of, depending | |
3065 | on IN_P) the range. */ | |
3066 | ||
3067 | static tree | |
3068 | build_range_check (type, exp, in_p, low, high) | |
3069 | tree type; | |
3070 | tree exp; | |
3071 | int in_p; | |
3072 | tree low, high; | |
3073 | { | |
3074 | tree etype = TREE_TYPE (exp); | |
3075 | tree utype, value; | |
3076 | ||
3077 | if (! in_p | |
3078 | && (0 != (value = build_range_check (type, exp, 1, low, high)))) | |
3079 | return invert_truthvalue (value); | |
3080 | ||
3081 | else if (low == 0 && high == 0) | |
3082 | return convert (type, integer_one_node); | |
3083 | ||
3084 | else if (low == 0) | |
3085 | return fold (build (LE_EXPR, type, exp, high)); | |
3086 | ||
3087 | else if (high == 0) | |
3088 | return fold (build (GE_EXPR, type, exp, low)); | |
3089 | ||
3090 | else if (operand_equal_p (low, high, 0)) | |
3091 | return fold (build (EQ_EXPR, type, exp, low)); | |
3092 | ||
3093 | else if (TREE_UNSIGNED (etype) && integer_zerop (low)) | |
3094 | return build_range_check (type, exp, 1, 0, high); | |
3095 | ||
3096 | else if (integer_zerop (low)) | |
ef659ec0 | 3097 | { |
ebde8a27 RK |
3098 | utype = unsigned_type (etype); |
3099 | return build_range_check (type, convert (utype, exp), 1, 0, | |
3100 | convert (utype, high)); | |
3101 | } | |
ef659ec0 | 3102 | |
ebde8a27 RK |
3103 | else if (0 != (value = const_binop (MINUS_EXPR, high, low, 0)) |
3104 | && ! TREE_OVERFLOW (value)) | |
3105 | return build_range_check (type, | |
3106 | fold (build (MINUS_EXPR, etype, exp, low)), | |
3107 | 1, convert (etype, integer_zero_node), value); | |
3108 | else | |
3109 | return 0; | |
3110 | } | |
3111 | \f | |
3112 | /* Given two ranges, see if we can merge them into one. Return 1 if we | |
3113 | can, 0 if we can't. Set the output range into the specified parameters. */ | |
ef659ec0 | 3114 | |
ebde8a27 RK |
3115 | static int |
3116 | merge_ranges (pin_p, plow, phigh, in0_p, low0, high0, in1_p, low1, high1) | |
3117 | int *pin_p; | |
3118 | tree *plow, *phigh; | |
3119 | int in0_p, in1_p; | |
3120 | tree low0, high0, low1, high1; | |
3121 | { | |
3122 | int no_overlap; | |
3123 | int subset; | |
3124 | int temp; | |
3125 | tree tem; | |
3126 | int in_p; | |
3127 | tree low, high; | |
ce2157a1 JL |
3128 | int lowequal = ((low0 == 0 && low1 == 0) |
3129 | || integer_onep (range_binop (EQ_EXPR, integer_type_node, | |
3130 | low0, 0, low1, 0))); | |
3131 | int highequal = ((high0 == 0 && high1 == 0) | |
3132 | || integer_onep (range_binop (EQ_EXPR, integer_type_node, | |
3133 | high0, 1, high1, 1))); | |
3134 | ||
3135 | /* Make range 0 be the range that starts first, or ends last if they | |
3136 | start at the same value. Swap them if it isn't. */ | |
ebde8a27 RK |
3137 | if (integer_onep (range_binop (GT_EXPR, integer_type_node, |
3138 | low0, 0, low1, 0)) | |
ce2157a1 | 3139 | || (lowequal |
ebde8a27 | 3140 | && integer_onep (range_binop (GT_EXPR, integer_type_node, |
ce2157a1 | 3141 | high1, 1, high0, 1)))) |
ebde8a27 RK |
3142 | { |
3143 | temp = in0_p, in0_p = in1_p, in1_p = temp; | |
3144 | tem = low0, low0 = low1, low1 = tem; | |
3145 | tem = high0, high0 = high1, high1 = tem; | |
3146 | } | |
ef659ec0 | 3147 | |
ebde8a27 RK |
3148 | /* Now flag two cases, whether the ranges are disjoint or whether the |
3149 | second range is totally subsumed in the first. Note that the tests | |
3150 | below are simplified by the ones above. */ | |
3151 | no_overlap = integer_onep (range_binop (LT_EXPR, integer_type_node, | |
3152 | high0, 1, low1, 0)); | |
5df8a1f2 | 3153 | subset = integer_onep (range_binop (LE_EXPR, integer_type_node, |
ebde8a27 RK |
3154 | high1, 1, high0, 1)); |
3155 | ||
3156 | /* We now have four cases, depending on whether we are including or | |
3157 | excluding the two ranges. */ | |
3158 | if (in0_p && in1_p) | |
3159 | { | |
3160 | /* If they don't overlap, the result is false. If the second range | |
3161 | is a subset it is the result. Otherwise, the range is from the start | |
3162 | of the second to the end of the first. */ | |
3163 | if (no_overlap) | |
3164 | in_p = 0, low = high = 0; | |
3165 | else if (subset) | |
3166 | in_p = 1, low = low1, high = high1; | |
3167 | else | |
3168 | in_p = 1, low = low1, high = high0; | |
3169 | } | |
ef659ec0 | 3170 | |
ebde8a27 RK |
3171 | else if (in0_p && ! in1_p) |
3172 | { | |
ce2157a1 JL |
3173 | /* If they don't overlap, the result is the first range. If they are |
3174 | equal, the result is false. If the second range is a subset of the | |
3175 | first, and the ranges begin at the same place, we go from just after | |
3176 | the end of the first range to the end of the second. If the second | |
3177 | range is not a subset of the first, or if it is a subset and both | |
3178 | ranges end at the same place, the range starts at the start of the | |
3179 | first range and ends just before the second range. | |
3180 | Otherwise, we can't describe this as a single range. */ | |
ebde8a27 RK |
3181 | if (no_overlap) |
3182 | in_p = 1, low = low0, high = high0; | |
ce2157a1 | 3183 | else if (lowequal && highequal) |
405862dd | 3184 | in_p = 0, low = high = 0; |
ce2157a1 JL |
3185 | else if (subset && lowequal) |
3186 | { | |
3187 | in_p = 1, high = high0; | |
3188 | low = range_binop (PLUS_EXPR, NULL_TREE, high1, 0, | |
3189 | integer_one_node, 0); | |
3190 | } | |
3191 | else if (! subset || highequal) | |
ebde8a27 RK |
3192 | { |
3193 | in_p = 1, low = low0; | |
3194 | high = range_binop (MINUS_EXPR, NULL_TREE, low1, 0, | |
0e1c7fc7 | 3195 | integer_one_node, 0); |
ebde8a27 | 3196 | } |
ce2157a1 JL |
3197 | else |
3198 | return 0; | |
ebde8a27 | 3199 | } |
ef659ec0 | 3200 | |
ebde8a27 RK |
3201 | else if (! in0_p && in1_p) |
3202 | { | |
3203 | /* If they don't overlap, the result is the second range. If the second | |
3204 | is a subset of the first, the result is false. Otherwise, | |
3205 | the range starts just after the first range and ends at the | |
3206 | end of the second. */ | |
3207 | if (no_overlap) | |
3208 | in_p = 1, low = low1, high = high1; | |
3209 | else if (subset) | |
3210 | in_p = 0, low = high = 0; | |
3211 | else | |
3212 | { | |
3213 | in_p = 1, high = high1; | |
3214 | low = range_binop (PLUS_EXPR, NULL_TREE, high0, 1, | |
3215 | integer_one_node, 0); | |
ef659ec0 TW |
3216 | } |
3217 | } | |
3218 | ||
ebde8a27 RK |
3219 | else |
3220 | { | |
3221 | /* The case where we are excluding both ranges. Here the complex case | |
3222 | is if they don't overlap. In that case, the only time we have a | |
3223 | range is if they are adjacent. If the second is a subset of the | |
3224 | first, the result is the first. Otherwise, the range to exclude | |
3225 | starts at the beginning of the first range and ends at the end of the | |
3226 | second. */ | |
3227 | if (no_overlap) | |
3228 | { | |
3229 | if (integer_onep (range_binop (EQ_EXPR, integer_type_node, | |
3230 | range_binop (PLUS_EXPR, NULL_TREE, | |
3231 | high0, 1, | |
3232 | integer_one_node, 1), | |
3233 | 1, low1, 0))) | |
3234 | in_p = 0, low = low0, high = high1; | |
3235 | else | |
3236 | return 0; | |
3237 | } | |
3238 | else if (subset) | |
3239 | in_p = 0, low = low0, high = high0; | |
3240 | else | |
3241 | in_p = 0, low = low0, high = high1; | |
3242 | } | |
f5902869 | 3243 | |
ebde8a27 RK |
3244 | *pin_p = in_p, *plow = low, *phigh = high; |
3245 | return 1; | |
3246 | } | |
3247 | \f | |
3248 | /* EXP is some logical combination of boolean tests. See if we can | |
3249 | merge it into some range test. Return the new tree if so. */ | |
ef659ec0 | 3250 | |
ebde8a27 RK |
3251 | static tree |
3252 | fold_range_test (exp) | |
3253 | tree exp; | |
3254 | { | |
3255 | int or_op = (TREE_CODE (exp) == TRUTH_ORIF_EXPR | |
3256 | || TREE_CODE (exp) == TRUTH_OR_EXPR); | |
3257 | int in0_p, in1_p, in_p; | |
3258 | tree low0, low1, low, high0, high1, high; | |
3259 | tree lhs = make_range (TREE_OPERAND (exp, 0), &in0_p, &low0, &high0); | |
3260 | tree rhs = make_range (TREE_OPERAND (exp, 1), &in1_p, &low1, &high1); | |
3261 | tree tem; | |
ef659ec0 | 3262 | |
ebde8a27 RK |
3263 | /* If this is an OR operation, invert both sides; we will invert |
3264 | again at the end. */ | |
3265 | if (or_op) | |
3266 | in0_p = ! in0_p, in1_p = ! in1_p; | |
3267 | ||
3268 | /* If both expressions are the same, if we can merge the ranges, and we | |
80906567 RK |
3269 | can build the range test, return it or it inverted. If one of the |
3270 | ranges is always true or always false, consider it to be the same | |
3271 | expression as the other. */ | |
3272 | if ((lhs == 0 || rhs == 0 || operand_equal_p (lhs, rhs, 0)) | |
ebde8a27 RK |
3273 | && merge_ranges (&in_p, &low, &high, in0_p, low0, high0, |
3274 | in1_p, low1, high1) | |
80906567 RK |
3275 | && 0 != (tem = (build_range_check (TREE_TYPE (exp), |
3276 | lhs != 0 ? lhs | |
3277 | : rhs != 0 ? rhs : integer_zero_node, | |
ebde8a27 RK |
3278 | in_p, low, high)))) |
3279 | return or_op ? invert_truthvalue (tem) : tem; | |
3280 | ||
3281 | /* On machines where the branch cost is expensive, if this is a | |
3282 | short-circuited branch and the underlying object on both sides | |
3283 | is the same, make a non-short-circuit operation. */ | |
3284 | else if (BRANCH_COST >= 2 | |
3285 | && (TREE_CODE (exp) == TRUTH_ANDIF_EXPR | |
3286 | || TREE_CODE (exp) == TRUTH_ORIF_EXPR) | |
3287 | && operand_equal_p (lhs, rhs, 0)) | |
ef659ec0 | 3288 | { |
f0eebf28 | 3289 | /* If simple enough, just rewrite. Otherwise, make a SAVE_EXPR |
9ec36da5 JL |
3290 | unless we are at top level or LHS contains a PLACEHOLDER_EXPR, in |
3291 | which cases we can't do this. */ | |
ebde8a27 RK |
3292 | if (simple_operand_p (lhs)) |
3293 | return build (TREE_CODE (exp) == TRUTH_ANDIF_EXPR | |
3294 | ? TRUTH_AND_EXPR : TRUTH_OR_EXPR, | |
3295 | TREE_TYPE (exp), TREE_OPERAND (exp, 0), | |
3296 | TREE_OPERAND (exp, 1)); | |
f0eebf28 | 3297 | |
9ec36da5 JL |
3298 | else if (current_function_decl != 0 |
3299 | && ! contains_placeholder_p (lhs)) | |
ebde8a27 RK |
3300 | { |
3301 | tree common = save_expr (lhs); | |
3302 | ||
3303 | if (0 != (lhs = build_range_check (TREE_TYPE (exp), common, | |
3304 | or_op ? ! in0_p : in0_p, | |
3305 | low0, high0)) | |
3306 | && (0 != (rhs = build_range_check (TREE_TYPE (exp), common, | |
3307 | or_op ? ! in1_p : in1_p, | |
3308 | low1, high1)))) | |
3309 | return build (TREE_CODE (exp) == TRUTH_ANDIF_EXPR | |
3310 | ? TRUTH_AND_EXPR : TRUTH_OR_EXPR, | |
3311 | TREE_TYPE (exp), lhs, rhs); | |
3312 | } | |
ef659ec0 | 3313 | } |
de153e82 JL |
3314 | |
3315 | ||
3316 | return 0; | |
ef659ec0 TW |
3317 | } |
3318 | \f | |
02103577 | 3319 | /* Subroutine for fold_truthop: C is an INTEGER_CST interpreted as a P |
25216284 | 3320 | bit value. Arrange things so the extra bits will be set to zero if and |
d4453ee5 RK |
3321 | only if C is signed-extended to its full width. If MASK is nonzero, |
3322 | it is an INTEGER_CST that should be AND'ed with the extra bits. */ | |
02103577 RK |
3323 | |
3324 | static tree | |
d4453ee5 | 3325 | unextend (c, p, unsignedp, mask) |
02103577 RK |
3326 | tree c; |
3327 | int p; | |
3328 | int unsignedp; | |
d4453ee5 | 3329 | tree mask; |
02103577 RK |
3330 | { |
3331 | tree type = TREE_TYPE (c); | |
3332 | int modesize = GET_MODE_BITSIZE (TYPE_MODE (type)); | |
3333 | tree temp; | |
3334 | ||
3335 | if (p == modesize || unsignedp) | |
3336 | return c; | |
3337 | ||
02103577 | 3338 | /* We work by getting just the sign bit into the low-order bit, then |
9faa82d8 | 3339 | into the high-order bit, then sign-extend. We then XOR that value |
02103577 RK |
3340 | with C. */ |
3341 | temp = const_binop (RSHIFT_EXPR, c, size_int (p - 1), 0); | |
3342 | temp = const_binop (BIT_AND_EXPR, temp, size_int (1), 0); | |
cf85c69b JW |
3343 | |
3344 | /* We must use a signed type in order to get an arithmetic right shift. | |
3345 | However, we must also avoid introducing accidental overflows, so that | |
3346 | a subsequent call to integer_zerop will work. Hence we must | |
3347 | do the type conversion here. At this point, the constant is either | |
3348 | zero or one, and the conversion to a signed type can never overflow. | |
3349 | We could get an overflow if this conversion is done anywhere else. */ | |
3350 | if (TREE_UNSIGNED (type)) | |
3351 | temp = convert (signed_type (type), temp); | |
3352 | ||
02103577 RK |
3353 | temp = const_binop (LSHIFT_EXPR, temp, size_int (modesize - 1), 0); |
3354 | temp = const_binop (RSHIFT_EXPR, temp, size_int (modesize - p - 1), 0); | |
d4453ee5 RK |
3355 | if (mask != 0) |
3356 | temp = const_binop (BIT_AND_EXPR, temp, convert (TREE_TYPE (c), mask), 0); | |
cf85c69b JW |
3357 | /* If necessary, convert the type back to match the type of C. */ |
3358 | if (TREE_UNSIGNED (type)) | |
3359 | temp = convert (type, temp); | |
d4453ee5 | 3360 | |
02103577 RK |
3361 | return convert (type, const_binop (BIT_XOR_EXPR, c, temp, 0)); |
3362 | } | |
3363 | \f | |
b2215d83 TW |
3364 | /* Find ways of folding logical expressions of LHS and RHS: |
3365 | Try to merge two comparisons to the same innermost item. | |
3366 | Look for range tests like "ch >= '0' && ch <= '9'". | |
3367 | Look for combinations of simple terms on machines with expensive branches | |
3368 | and evaluate the RHS unconditionally. | |
6d716ca8 RS |
3369 | |
3370 | For example, if we have p->a == 2 && p->b == 4 and we can make an | |
3371 | object large enough to span both A and B, we can do this with a comparison | |
3372 | against the object ANDed with the a mask. | |
3373 | ||
3374 | If we have p->a == q->a && p->b == q->b, we may be able to use bit masking | |
3375 | operations to do this with one comparison. | |
3376 | ||
3377 | We check for both normal comparisons and the BIT_AND_EXPRs made this by | |
3378 | function and the one above. | |
3379 | ||
3380 | CODE is the logical operation being done. It can be TRUTH_ANDIF_EXPR, | |
3381 | TRUTH_AND_EXPR, TRUTH_ORIF_EXPR, or TRUTH_OR_EXPR. | |
3382 | ||
3383 | TRUTH_TYPE is the type of the logical operand and LHS and RHS are its | |
3384 | two operands. | |
3385 | ||
3386 | We return the simplified tree or 0 if no optimization is possible. */ | |
3387 | ||
3388 | static tree | |
b2215d83 | 3389 | fold_truthop (code, truth_type, lhs, rhs) |
6d716ca8 RS |
3390 | enum tree_code code; |
3391 | tree truth_type, lhs, rhs; | |
3392 | { | |
3393 | /* If this is the "or" of two comparisons, we can do something if we | |
3394 | the comparisons are NE_EXPR. If this is the "and", we can do something | |
3395 | if the comparisons are EQ_EXPR. I.e., | |
3396 | (a->b == 2 && a->c == 4) can become (a->new == NEW). | |
3397 | ||
3398 | WANTED_CODE is this operation code. For single bit fields, we can | |
3399 | convert EQ_EXPR to NE_EXPR so we need not reject the "wrong" | |
3400 | comparison for one-bit fields. */ | |
3401 | ||
b2215d83 | 3402 | enum tree_code wanted_code; |
6d716ca8 | 3403 | enum tree_code lcode, rcode; |
b2215d83 | 3404 | tree ll_arg, lr_arg, rl_arg, rr_arg; |
6d716ca8 RS |
3405 | tree ll_inner, lr_inner, rl_inner, rr_inner; |
3406 | int ll_bitsize, ll_bitpos, lr_bitsize, lr_bitpos; | |
3407 | int rl_bitsize, rl_bitpos, rr_bitsize, rr_bitpos; | |
3408 | int xll_bitpos, xlr_bitpos, xrl_bitpos, xrr_bitpos; | |
3409 | int lnbitsize, lnbitpos, rnbitsize, rnbitpos; | |
3410 | int ll_unsignedp, lr_unsignedp, rl_unsignedp, rr_unsignedp; | |
3411 | enum machine_mode ll_mode, lr_mode, rl_mode, rr_mode; | |
3412 | enum machine_mode lnmode, rnmode; | |
3413 | tree ll_mask, lr_mask, rl_mask, rr_mask; | |
d4453ee5 | 3414 | tree ll_and_mask, lr_and_mask, rl_and_mask, rr_and_mask; |
b2215d83 | 3415 | tree l_const, r_const; |
6d716ca8 RS |
3416 | tree type, result; |
3417 | int first_bit, end_bit; | |
b2215d83 | 3418 | int volatilep; |
6d716ca8 | 3419 | |
ebde8a27 RK |
3420 | /* Start by getting the comparison codes. Fail if anything is volatile. |
3421 | If one operand is a BIT_AND_EXPR with the constant one, treat it as if | |
3422 | it were surrounded with a NE_EXPR. */ | |
6d716ca8 | 3423 | |
ebde8a27 | 3424 | if (TREE_SIDE_EFFECTS (lhs) || TREE_SIDE_EFFECTS (rhs)) |
b2215d83 TW |
3425 | return 0; |
3426 | ||
6d716ca8 RS |
3427 | lcode = TREE_CODE (lhs); |
3428 | rcode = TREE_CODE (rhs); | |
ef659ec0 | 3429 | |
96d4cf0a RK |
3430 | if (lcode == BIT_AND_EXPR && integer_onep (TREE_OPERAND (lhs, 1))) |
3431 | lcode = NE_EXPR, lhs = build (NE_EXPR, truth_type, lhs, integer_zero_node); | |
3432 | ||
3433 | if (rcode == BIT_AND_EXPR && integer_onep (TREE_OPERAND (rhs, 1))) | |
3434 | rcode = NE_EXPR, rhs = build (NE_EXPR, truth_type, rhs, integer_zero_node); | |
3435 | ||
ebde8a27 | 3436 | if (TREE_CODE_CLASS (lcode) != '<' || TREE_CODE_CLASS (rcode) != '<') |
ef659ec0 TW |
3437 | return 0; |
3438 | ||
b2215d83 | 3439 | code = ((code == TRUTH_AND_EXPR || code == TRUTH_ANDIF_EXPR) |
9c0ae98b | 3440 | ? TRUTH_AND_EXPR : TRUTH_OR_EXPR); |
b2215d83 TW |
3441 | |
3442 | ll_arg = TREE_OPERAND (lhs, 0); | |
3443 | lr_arg = TREE_OPERAND (lhs, 1); | |
3444 | rl_arg = TREE_OPERAND (rhs, 0); | |
3445 | rr_arg = TREE_OPERAND (rhs, 1); | |
3446 | ||
8227896c | 3447 | /* If the RHS can be evaluated unconditionally and its operands are |
b2215d83 TW |
3448 | simple, it wins to evaluate the RHS unconditionally on machines |
3449 | with expensive branches. In this case, this isn't a comparison | |
3450 | that can be merged. */ | |
3451 | ||
3452 | /* @@ I'm not sure it wins on the m88110 to do this if the comparisons | |
3453 | are with zero (tmw). */ | |
3454 | ||
3455 | if (BRANCH_COST >= 2 | |
7178e3af | 3456 | && INTEGRAL_TYPE_P (TREE_TYPE (rhs)) |
b2215d83 | 3457 | && simple_operand_p (rl_arg) |
8227896c | 3458 | && simple_operand_p (rr_arg)) |
b2215d83 TW |
3459 | return build (code, truth_type, lhs, rhs); |
3460 | ||
ef659ec0 TW |
3461 | /* See if the comparisons can be merged. Then get all the parameters for |
3462 | each side. */ | |
3463 | ||
6d716ca8 | 3464 | if ((lcode != EQ_EXPR && lcode != NE_EXPR) |
ef659ec0 | 3465 | || (rcode != EQ_EXPR && rcode != NE_EXPR)) |
6d716ca8 RS |
3466 | return 0; |
3467 | ||
b2215d83 TW |
3468 | volatilep = 0; |
3469 | ll_inner = decode_field_reference (ll_arg, | |
6d716ca8 | 3470 | &ll_bitsize, &ll_bitpos, &ll_mode, |
d4453ee5 RK |
3471 | &ll_unsignedp, &volatilep, &ll_mask, |
3472 | &ll_and_mask); | |
b2215d83 | 3473 | lr_inner = decode_field_reference (lr_arg, |
6d716ca8 | 3474 | &lr_bitsize, &lr_bitpos, &lr_mode, |
d4453ee5 RK |
3475 | &lr_unsignedp, &volatilep, &lr_mask, |
3476 | &lr_and_mask); | |
b2215d83 | 3477 | rl_inner = decode_field_reference (rl_arg, |
6d716ca8 | 3478 | &rl_bitsize, &rl_bitpos, &rl_mode, |
d4453ee5 RK |
3479 | &rl_unsignedp, &volatilep, &rl_mask, |
3480 | &rl_and_mask); | |
b2215d83 | 3481 | rr_inner = decode_field_reference (rr_arg, |
6d716ca8 | 3482 | &rr_bitsize, &rr_bitpos, &rr_mode, |
d4453ee5 RK |
3483 | &rr_unsignedp, &volatilep, &rr_mask, |
3484 | &rr_and_mask); | |
6d716ca8 RS |
3485 | |
3486 | /* It must be true that the inner operation on the lhs of each | |
3487 | comparison must be the same if we are to be able to do anything. | |
3488 | Then see if we have constants. If not, the same must be true for | |
3489 | the rhs's. */ | |
3490 | if (volatilep || ll_inner == 0 || rl_inner == 0 | |
3491 | || ! operand_equal_p (ll_inner, rl_inner, 0)) | |
3492 | return 0; | |
3493 | ||
b2215d83 TW |
3494 | if (TREE_CODE (lr_arg) == INTEGER_CST |
3495 | && TREE_CODE (rr_arg) == INTEGER_CST) | |
3496 | l_const = lr_arg, r_const = rr_arg; | |
6d716ca8 RS |
3497 | else if (lr_inner == 0 || rr_inner == 0 |
3498 | || ! operand_equal_p (lr_inner, rr_inner, 0)) | |
3499 | return 0; | |
b2215d83 TW |
3500 | else |
3501 | l_const = r_const = 0; | |
6d716ca8 RS |
3502 | |
3503 | /* If either comparison code is not correct for our logical operation, | |
3504 | fail. However, we can convert a one-bit comparison against zero into | |
3505 | the opposite comparison against that bit being set in the field. */ | |
b2215d83 | 3506 | |
9c0ae98b | 3507 | wanted_code = (code == TRUTH_AND_EXPR ? EQ_EXPR : NE_EXPR); |
6d716ca8 RS |
3508 | if (lcode != wanted_code) |
3509 | { | |
3510 | if (l_const && integer_zerop (l_const) && integer_pow2p (ll_mask)) | |
5a6b3365 | 3511 | { |
9f29ca78 | 3512 | if (ll_unsignedp || tree_log2 (ll_mask) + 1 < ll_bitsize) |
5a6b3365 R |
3513 | l_const = ll_mask; |
3514 | else | |
3515 | /* Since ll_arg is a single bit bit mask, we can sign extend | |
3516 | it appropriately with a NEGATE_EXPR. | |
3517 | l_const is made a signed value here, but since for l_const != NULL | |
3518 | lr_unsignedp is not used, we don't need to clear the latter. */ | |
3519 | l_const = fold (build1 (NEGATE_EXPR, TREE_TYPE (ll_arg), | |
3520 | convert (TREE_TYPE (ll_arg), ll_mask))); | |
3521 | } | |
6d716ca8 RS |
3522 | else |
3523 | return 0; | |
3524 | } | |
3525 | ||
3526 | if (rcode != wanted_code) | |
3527 | { | |
3528 | if (r_const && integer_zerop (r_const) && integer_pow2p (rl_mask)) | |
5a6b3365 | 3529 | { |
9f29ca78 | 3530 | if (rl_unsignedp || tree_log2 (rl_mask) + 1 < rl_bitsize) |
5a6b3365 R |
3531 | r_const = rl_mask; |
3532 | else | |
3533 | /* This is analogous to the code for l_const above. */ | |
3534 | r_const = fold (build1 (NEGATE_EXPR, TREE_TYPE (rl_arg), | |
3535 | convert (TREE_TYPE (rl_arg), rl_mask))); | |
3536 | } | |
6d716ca8 RS |
3537 | else |
3538 | return 0; | |
3539 | } | |
3540 | ||
3541 | /* See if we can find a mode that contains both fields being compared on | |
3542 | the left. If we can't, fail. Otherwise, update all constants and masks | |
3543 | to be relative to a field of that size. */ | |
3544 | first_bit = MIN (ll_bitpos, rl_bitpos); | |
3545 | end_bit = MAX (ll_bitpos + ll_bitsize, rl_bitpos + rl_bitsize); | |
3546 | lnmode = get_best_mode (end_bit - first_bit, first_bit, | |
3547 | TYPE_ALIGN (TREE_TYPE (ll_inner)), word_mode, | |
3548 | volatilep); | |
3549 | if (lnmode == VOIDmode) | |
3550 | return 0; | |
3551 | ||
3552 | lnbitsize = GET_MODE_BITSIZE (lnmode); | |
3553 | lnbitpos = first_bit & ~ (lnbitsize - 1); | |
3554 | type = type_for_size (lnbitsize, 1); | |
3555 | xll_bitpos = ll_bitpos - lnbitpos, xrl_bitpos = rl_bitpos - lnbitpos; | |
3556 | ||
f76b9db2 ILT |
3557 | if (BYTES_BIG_ENDIAN) |
3558 | { | |
3559 | xll_bitpos = lnbitsize - xll_bitpos - ll_bitsize; | |
3560 | xrl_bitpos = lnbitsize - xrl_bitpos - rl_bitsize; | |
3561 | } | |
6d716ca8 RS |
3562 | |
3563 | ll_mask = const_binop (LSHIFT_EXPR, convert (type, ll_mask), | |
91d33e36 | 3564 | size_int (xll_bitpos), 0); |
6d716ca8 | 3565 | rl_mask = const_binop (LSHIFT_EXPR, convert (type, rl_mask), |
91d33e36 | 3566 | size_int (xrl_bitpos), 0); |
6d716ca8 | 3567 | |
6d716ca8 RS |
3568 | if (l_const) |
3569 | { | |
d4453ee5 RK |
3570 | l_const = convert (type, l_const); |
3571 | l_const = unextend (l_const, ll_bitsize, ll_unsignedp, ll_and_mask); | |
02103577 RK |
3572 | l_const = const_binop (LSHIFT_EXPR, l_const, size_int (xll_bitpos), 0); |
3573 | if (! integer_zerop (const_binop (BIT_AND_EXPR, l_const, | |
3574 | fold (build1 (BIT_NOT_EXPR, | |
3575 | type, ll_mask)), | |
3576 | 0))) | |
3577 | { | |
3578 | warning ("comparison is always %s", | |
3579 | wanted_code == NE_EXPR ? "one" : "zero"); | |
3580 | ||
3581 | return convert (truth_type, | |
3582 | wanted_code == NE_EXPR | |
3583 | ? integer_one_node : integer_zero_node); | |
3584 | } | |
6d716ca8 RS |
3585 | } |
3586 | if (r_const) | |
3587 | { | |
d4453ee5 RK |
3588 | r_const = convert (type, r_const); |
3589 | r_const = unextend (r_const, rl_bitsize, rl_unsignedp, rl_and_mask); | |
02103577 RK |
3590 | r_const = const_binop (LSHIFT_EXPR, r_const, size_int (xrl_bitpos), 0); |
3591 | if (! integer_zerop (const_binop (BIT_AND_EXPR, r_const, | |
3592 | fold (build1 (BIT_NOT_EXPR, | |
3593 | type, rl_mask)), | |
3594 | 0))) | |
3595 | { | |
3596 | warning ("comparison is always %s", | |
3597 | wanted_code == NE_EXPR ? "one" : "zero"); | |
3598 | ||
3599 | return convert (truth_type, | |
3600 | wanted_code == NE_EXPR | |
3601 | ? integer_one_node : integer_zero_node); | |
3602 | } | |
6d716ca8 RS |
3603 | } |
3604 | ||
3605 | /* If the right sides are not constant, do the same for it. Also, | |
3606 | disallow this optimization if a size or signedness mismatch occurs | |
3607 | between the left and right sides. */ | |
3608 | if (l_const == 0) | |
3609 | { | |
3610 | if (ll_bitsize != lr_bitsize || rl_bitsize != rr_bitsize | |
e6a28f26 RS |
3611 | || ll_unsignedp != lr_unsignedp || rl_unsignedp != rr_unsignedp |
3612 | /* Make sure the two fields on the right | |
3613 | correspond to the left without being swapped. */ | |
3614 | || ll_bitpos - rl_bitpos != lr_bitpos - rr_bitpos) | |
6d716ca8 RS |
3615 | return 0; |
3616 | ||
3617 | first_bit = MIN (lr_bitpos, rr_bitpos); | |
3618 | end_bit = MAX (lr_bitpos + lr_bitsize, rr_bitpos + rr_bitsize); | |
3619 | rnmode = get_best_mode (end_bit - first_bit, first_bit, | |
3620 | TYPE_ALIGN (TREE_TYPE (lr_inner)), word_mode, | |
3621 | volatilep); | |
3622 | if (rnmode == VOIDmode) | |
3623 | return 0; | |
3624 | ||
3625 | rnbitsize = GET_MODE_BITSIZE (rnmode); | |
3626 | rnbitpos = first_bit & ~ (rnbitsize - 1); | |
3627 | xlr_bitpos = lr_bitpos - rnbitpos, xrr_bitpos = rr_bitpos - rnbitpos; | |
3628 | ||
f76b9db2 ILT |
3629 | if (BYTES_BIG_ENDIAN) |
3630 | { | |
3631 | xlr_bitpos = rnbitsize - xlr_bitpos - lr_bitsize; | |
3632 | xrr_bitpos = rnbitsize - xrr_bitpos - rr_bitsize; | |
3633 | } | |
6d716ca8 RS |
3634 | |
3635 | lr_mask = const_binop (LSHIFT_EXPR, convert (type, lr_mask), | |
91d33e36 | 3636 | size_int (xlr_bitpos), 0); |
6d716ca8 | 3637 | rr_mask = const_binop (LSHIFT_EXPR, convert (type, rr_mask), |
91d33e36 | 3638 | size_int (xrr_bitpos), 0); |
6d716ca8 RS |
3639 | |
3640 | /* Make a mask that corresponds to both fields being compared. | |
3641 | Do this for both items being compared. If the masks agree, | |
3642 | we can do this by masking both and comparing the masked | |
3643 | results. */ | |
91d33e36 RS |
3644 | ll_mask = const_binop (BIT_IOR_EXPR, ll_mask, rl_mask, 0); |
3645 | lr_mask = const_binop (BIT_IOR_EXPR, lr_mask, rr_mask, 0); | |
6d716ca8 RS |
3646 | if (operand_equal_p (ll_mask, lr_mask, 0) && lnbitsize == rnbitsize) |
3647 | { | |
3648 | lhs = make_bit_field_ref (ll_inner, type, lnbitsize, lnbitpos, | |
3649 | ll_unsignedp || rl_unsignedp); | |
3650 | rhs = make_bit_field_ref (lr_inner, type, rnbitsize, rnbitpos, | |
3651 | lr_unsignedp || rr_unsignedp); | |
3652 | if (! all_ones_mask_p (ll_mask, lnbitsize)) | |
3653 | { | |
3654 | lhs = build (BIT_AND_EXPR, type, lhs, ll_mask); | |
3655 | rhs = build (BIT_AND_EXPR, type, rhs, ll_mask); | |
3656 | } | |
3657 | return build (wanted_code, truth_type, lhs, rhs); | |
3658 | } | |
3659 | ||
3660 | /* There is still another way we can do something: If both pairs of | |
3661 | fields being compared are adjacent, we may be able to make a wider | |
3662 | field containing them both. */ | |
3663 | if ((ll_bitsize + ll_bitpos == rl_bitpos | |
3664 | && lr_bitsize + lr_bitpos == rr_bitpos) | |
3665 | || (ll_bitpos == rl_bitpos + rl_bitsize | |
3666 | && lr_bitpos == rr_bitpos + rr_bitsize)) | |
3667 | return build (wanted_code, truth_type, | |
3668 | make_bit_field_ref (ll_inner, type, | |
3669 | ll_bitsize + rl_bitsize, | |
3670 | MIN (ll_bitpos, rl_bitpos), | |
3671 | ll_unsignedp), | |
3672 | make_bit_field_ref (lr_inner, type, | |
3673 | lr_bitsize + rr_bitsize, | |
3674 | MIN (lr_bitpos, rr_bitpos), | |
3675 | lr_unsignedp)); | |
3676 | ||
3677 | return 0; | |
3678 | } | |
3679 | ||
3680 | /* Handle the case of comparisons with constants. If there is something in | |
3681 | common between the masks, those bits of the constants must be the same. | |
3682 | If not, the condition is always false. Test for this to avoid generating | |
3683 | incorrect code below. */ | |
91d33e36 | 3684 | result = const_binop (BIT_AND_EXPR, ll_mask, rl_mask, 0); |
6d716ca8 | 3685 | if (! integer_zerop (result) |
91d33e36 RS |
3686 | && simple_cst_equal (const_binop (BIT_AND_EXPR, result, l_const, 0), |
3687 | const_binop (BIT_AND_EXPR, result, r_const, 0)) != 1) | |
6d716ca8 RS |
3688 | { |
3689 | if (wanted_code == NE_EXPR) | |
3690 | { | |
3691 | warning ("`or' of unmatched not-equal tests is always 1"); | |
3692 | return convert (truth_type, integer_one_node); | |
3693 | } | |
3694 | else | |
3695 | { | |
3696 | warning ("`and' of mutually exclusive equal-tests is always zero"); | |
3697 | return convert (truth_type, integer_zero_node); | |
3698 | } | |
3699 | } | |
3700 | ||
3701 | /* Construct the expression we will return. First get the component | |
3702 | reference we will make. Unless the mask is all ones the width of | |
3703 | that field, perform the mask operation. Then compare with the | |
3704 | merged constant. */ | |
3705 | result = make_bit_field_ref (ll_inner, type, lnbitsize, lnbitpos, | |
3706 | ll_unsignedp || rl_unsignedp); | |
3707 | ||
91d33e36 | 3708 | ll_mask = const_binop (BIT_IOR_EXPR, ll_mask, rl_mask, 0); |
6d716ca8 RS |
3709 | if (! all_ones_mask_p (ll_mask, lnbitsize)) |
3710 | result = build (BIT_AND_EXPR, type, result, ll_mask); | |
3711 | ||
3712 | return build (wanted_code, truth_type, result, | |
91d33e36 | 3713 | const_binop (BIT_IOR_EXPR, l_const, r_const, 0)); |
6d716ca8 RS |
3714 | } |
3715 | \f | |
b5f3b6b6 RK |
3716 | /* If T contains a COMPOUND_EXPR which was inserted merely to evaluate |
3717 | S, a SAVE_EXPR, return the expression actually being evaluated. Note | |
3718 | that we may sometimes modify the tree. */ | |
3719 | ||
3720 | static tree | |
3721 | strip_compound_expr (t, s) | |
3722 | tree t; | |
3723 | tree s; | |
3724 | { | |
b5f3b6b6 RK |
3725 | enum tree_code code = TREE_CODE (t); |
3726 | ||
3727 | /* See if this is the COMPOUND_EXPR we want to eliminate. */ | |
3728 | if (code == COMPOUND_EXPR && TREE_CODE (TREE_OPERAND (t, 0)) == CONVERT_EXPR | |
3729 | && TREE_OPERAND (TREE_OPERAND (t, 0), 0) == s) | |
3730 | return TREE_OPERAND (t, 1); | |
3731 | ||
3732 | /* See if this is a COND_EXPR or a simple arithmetic operator. We | |
3733 | don't bother handling any other types. */ | |
3734 | else if (code == COND_EXPR) | |
3735 | { | |
3736 | TREE_OPERAND (t, 0) = strip_compound_expr (TREE_OPERAND (t, 0), s); | |
3737 | TREE_OPERAND (t, 1) = strip_compound_expr (TREE_OPERAND (t, 1), s); | |
3738 | TREE_OPERAND (t, 2) = strip_compound_expr (TREE_OPERAND (t, 2), s); | |
3739 | } | |
3740 | else if (TREE_CODE_CLASS (code) == '1') | |
3741 | TREE_OPERAND (t, 0) = strip_compound_expr (TREE_OPERAND (t, 0), s); | |
3742 | else if (TREE_CODE_CLASS (code) == '<' | |
3743 | || TREE_CODE_CLASS (code) == '2') | |
3744 | { | |
3745 | TREE_OPERAND (t, 0) = strip_compound_expr (TREE_OPERAND (t, 0), s); | |
3746 | TREE_OPERAND (t, 1) = strip_compound_expr (TREE_OPERAND (t, 1), s); | |
3747 | } | |
3748 | ||
3749 | return t; | |
3750 | } | |
3751 | \f | |
f628873f MM |
3752 | /* Return a node which has the indicated constant VALUE (either 0 or |
3753 | 1), and is of the indicated TYPE. */ | |
3754 | ||
83e0821b | 3755 | static tree |
f628873f MM |
3756 | constant_boolean_node (value, type) |
3757 | int value; | |
3758 | tree type; | |
3759 | { | |
3760 | if (type == integer_type_node) | |
3761 | return value ? integer_one_node : integer_zero_node; | |
3762 | else if (TREE_CODE (type) == BOOLEAN_TYPE) | |
3763 | return truthvalue_conversion (value ? integer_one_node : | |
3764 | integer_zero_node); | |
3765 | else | |
3766 | { | |
3767 | tree t = build_int_2 (value, 0); | |
3768 | TREE_TYPE (t) = type; | |
3769 | return t; | |
3770 | } | |
3771 | } | |
3772 | ||
6d716ca8 RS |
3773 | /* Perform constant folding and related simplification of EXPR. |
3774 | The related simplifications include x*1 => x, x*0 => 0, etc., | |
3775 | and application of the associative law. | |
3776 | NOP_EXPR conversions may be removed freely (as long as we | |
3777 | are careful not to change the C type of the overall expression) | |
3778 | We cannot simplify through a CONVERT_EXPR, FIX_EXPR or FLOAT_EXPR, | |
3779 | but we can constant-fold them if they have constant operands. */ | |
3780 | ||
3781 | tree | |
3782 | fold (expr) | |
3783 | tree expr; | |
3784 | { | |
3785 | register tree t = expr; | |
3786 | tree t1 = NULL_TREE; | |
c05a9b68 | 3787 | tree tem; |
6d716ca8 | 3788 | tree type = TREE_TYPE (expr); |
4e86caed | 3789 | register tree arg0 = NULL_TREE, arg1 = NULL_TREE; |
6d716ca8 RS |
3790 | register enum tree_code code = TREE_CODE (t); |
3791 | register int kind; | |
c05a9b68 | 3792 | int invert; |
6d716ca8 RS |
3793 | |
3794 | /* WINS will be nonzero when the switch is done | |
3795 | if all operands are constant. */ | |
3796 | ||
3797 | int wins = 1; | |
3798 | ||
5fd7f37d RK |
3799 | /* Don't try to process an RTL_EXPR since its operands aren't trees. |
3800 | Likewise for a SAVE_EXPR that's already been evaluated. */ | |
3801 | if (code == RTL_EXPR || (code == SAVE_EXPR && SAVE_EXPR_RTL (t)) != 0) | |
ac27d589 RK |
3802 | return t; |
3803 | ||
6d716ca8 RS |
3804 | /* Return right away if already constant. */ |
3805 | if (TREE_CONSTANT (t)) | |
3806 | { | |
3807 | if (code == CONST_DECL) | |
3808 | return DECL_INITIAL (t); | |
3809 | return t; | |
3810 | } | |
3811 | ||
dbecbbe4 JL |
3812 | #ifdef MAX_INTEGER_COMPUTATION_MODE |
3813 | check_max_integer_computation_mode (expr); | |
3814 | #endif | |
3815 | ||
6d716ca8 | 3816 | kind = TREE_CODE_CLASS (code); |
1b81aa14 RS |
3817 | if (code == NOP_EXPR || code == FLOAT_EXPR || code == CONVERT_EXPR) |
3818 | { | |
1cc1b11a RS |
3819 | tree subop; |
3820 | ||
1b81aa14 RS |
3821 | /* Special case for conversion ops that can have fixed point args. */ |
3822 | arg0 = TREE_OPERAND (t, 0); | |
3823 | ||
3824 | /* Don't use STRIP_NOPS, because signedness of argument type matters. */ | |
3825 | if (arg0 != 0) | |
3826 | STRIP_TYPE_NOPS (arg0); | |
3827 | ||
1cc1b11a RS |
3828 | if (arg0 != 0 && TREE_CODE (arg0) == COMPLEX_CST) |
3829 | subop = TREE_REALPART (arg0); | |
3830 | else | |
3831 | subop = arg0; | |
3832 | ||
3833 | if (subop != 0 && TREE_CODE (subop) != INTEGER_CST | |
1b81aa14 | 3834 | #if ! defined (REAL_IS_NOT_DOUBLE) || defined (REAL_ARITHMETIC) |
1cc1b11a | 3835 | && TREE_CODE (subop) != REAL_CST |
1b81aa14 RS |
3836 | #endif /* not REAL_IS_NOT_DOUBLE, or REAL_ARITHMETIC */ |
3837 | ) | |
3838 | /* Note that TREE_CONSTANT isn't enough: | |
3839 | static var addresses are constant but we can't | |
3840 | do arithmetic on them. */ | |
3841 | wins = 0; | |
3842 | } | |
3843 | else if (kind == 'e' || kind == '<' | |
3844 | || kind == '1' || kind == '2' || kind == 'r') | |
6d716ca8 RS |
3845 | { |
3846 | register int len = tree_code_length[(int) code]; | |
3847 | register int i; | |
3848 | for (i = 0; i < len; i++) | |
3849 | { | |
3850 | tree op = TREE_OPERAND (t, i); | |
1cc1b11a | 3851 | tree subop; |
6d716ca8 RS |
3852 | |
3853 | if (op == 0) | |
3854 | continue; /* Valid for CALL_EXPR, at least. */ | |
3855 | ||
b8a91430 RK |
3856 | if (kind == '<' || code == RSHIFT_EXPR) |
3857 | { | |
3858 | /* Signedness matters here. Perhaps we can refine this | |
3859 | later. */ | |
3860 | STRIP_TYPE_NOPS (op); | |
3861 | } | |
3862 | else | |
3863 | { | |
3864 | /* Strip any conversions that don't change the mode. */ | |
3865 | STRIP_NOPS (op); | |
3866 | } | |
6d716ca8 | 3867 | |
1cc1b11a RS |
3868 | if (TREE_CODE (op) == COMPLEX_CST) |
3869 | subop = TREE_REALPART (op); | |
3870 | else | |
3871 | subop = op; | |
3872 | ||
3873 | if (TREE_CODE (subop) != INTEGER_CST | |
6d716ca8 | 3874 | #if ! defined (REAL_IS_NOT_DOUBLE) || defined (REAL_ARITHMETIC) |
1cc1b11a | 3875 | && TREE_CODE (subop) != REAL_CST |
6d716ca8 RS |
3876 | #endif /* not REAL_IS_NOT_DOUBLE, or REAL_ARITHMETIC */ |
3877 | ) | |
3878 | /* Note that TREE_CONSTANT isn't enough: | |
3879 | static var addresses are constant but we can't | |
3880 | do arithmetic on them. */ | |
3881 | wins = 0; | |
3882 | ||
3883 | if (i == 0) | |
3884 | arg0 = op; | |
3885 | else if (i == 1) | |
3886 | arg1 = op; | |
3887 | } | |
3888 | } | |
3889 | ||
3890 | /* If this is a commutative operation, and ARG0 is a constant, move it | |
3891 | to ARG1 to reduce the number of tests below. */ | |
3892 | if ((code == PLUS_EXPR || code == MULT_EXPR || code == MIN_EXPR | |
3893 | || code == MAX_EXPR || code == BIT_IOR_EXPR || code == BIT_XOR_EXPR | |
3894 | || code == BIT_AND_EXPR) | |
3895 | && (TREE_CODE (arg0) == INTEGER_CST || TREE_CODE (arg0) == REAL_CST)) | |
3896 | { | |
c05a9b68 | 3897 | tem = arg0; arg0 = arg1; arg1 = tem; |
6d716ca8 | 3898 | |
c05a9b68 RS |
3899 | tem = TREE_OPERAND (t, 0); TREE_OPERAND (t, 0) = TREE_OPERAND (t, 1); |
3900 | TREE_OPERAND (t, 1) = tem; | |
6d716ca8 RS |
3901 | } |
3902 | ||
3903 | /* Now WINS is set as described above, | |
3904 | ARG0 is the first operand of EXPR, | |
3905 | and ARG1 is the second operand (if it has more than one operand). | |
3906 | ||
3907 | First check for cases where an arithmetic operation is applied to a | |
3908 | compound, conditional, or comparison operation. Push the arithmetic | |
3909 | operation inside the compound or conditional to see if any folding | |
3910 | can then be done. Convert comparison to conditional for this purpose. | |
3911 | The also optimizes non-constant cases that used to be done in | |
96d4cf0a RK |
3912 | expand_expr. |
3913 | ||
3914 | Before we do that, see if this is a BIT_AND_EXPR or a BIT_OR_EXPR, | |
61f275ff RK |
3915 | one of the operands is a comparison and the other is a comparison, a |
3916 | BIT_AND_EXPR with the constant 1, or a truth value. In that case, the | |
3917 | code below would make the expression more complex. Change it to a | |
2df46b06 RK |
3918 | TRUTH_{AND,OR}_EXPR. Likewise, convert a similar NE_EXPR to |
3919 | TRUTH_XOR_EXPR and an EQ_EXPR to the inversion of a TRUTH_XOR_EXPR. */ | |
96d4cf0a | 3920 | |
2df46b06 RK |
3921 | if ((code == BIT_AND_EXPR || code == BIT_IOR_EXPR |
3922 | || code == EQ_EXPR || code == NE_EXPR) | |
61f275ff RK |
3923 | && ((truth_value_p (TREE_CODE (arg0)) |
3924 | && (truth_value_p (TREE_CODE (arg1)) | |
96d4cf0a RK |
3925 | || (TREE_CODE (arg1) == BIT_AND_EXPR |
3926 | && integer_onep (TREE_OPERAND (arg1, 1))))) | |
61f275ff RK |
3927 | || (truth_value_p (TREE_CODE (arg1)) |
3928 | && (truth_value_p (TREE_CODE (arg0)) | |
96d4cf0a RK |
3929 | || (TREE_CODE (arg0) == BIT_AND_EXPR |
3930 | && integer_onep (TREE_OPERAND (arg0, 1))))))) | |
2df46b06 RK |
3931 | { |
3932 | t = fold (build (code == BIT_AND_EXPR ? TRUTH_AND_EXPR | |
3933 | : code == BIT_IOR_EXPR ? TRUTH_OR_EXPR | |
3934 | : TRUTH_XOR_EXPR, | |
3935 | type, arg0, arg1)); | |
3936 | ||
3937 | if (code == EQ_EXPR) | |
3938 | t = invert_truthvalue (t); | |
3939 | ||
3940 | return t; | |
3941 | } | |
96d4cf0a | 3942 | |
6d716ca8 RS |
3943 | if (TREE_CODE_CLASS (code) == '1') |
3944 | { | |
3945 | if (TREE_CODE (arg0) == COMPOUND_EXPR) | |
3946 | return build (COMPOUND_EXPR, type, TREE_OPERAND (arg0, 0), | |
3947 | fold (build1 (code, type, TREE_OPERAND (arg0, 1)))); | |
3948 | else if (TREE_CODE (arg0) == COND_EXPR) | |
b8eb43a2 RK |
3949 | { |
3950 | t = fold (build (COND_EXPR, type, TREE_OPERAND (arg0, 0), | |
3951 | fold (build1 (code, type, TREE_OPERAND (arg0, 1))), | |
3952 | fold (build1 (code, type, TREE_OPERAND (arg0, 2))))); | |
3953 | ||
3954 | /* If this was a conversion, and all we did was to move into | |
e1f56f62 RK |
3955 | inside the COND_EXPR, bring it back out. But leave it if |
3956 | it is a conversion from integer to integer and the | |
3957 | result precision is no wider than a word since such a | |
3958 | conversion is cheap and may be optimized away by combine, | |
3959 | while it couldn't if it were outside the COND_EXPR. Then return | |
3960 | so we don't get into an infinite recursion loop taking the | |
3961 | conversion out and then back in. */ | |
b8eb43a2 RK |
3962 | |
3963 | if ((code == NOP_EXPR || code == CONVERT_EXPR | |
3964 | || code == NON_LVALUE_EXPR) | |
3965 | && TREE_CODE (t) == COND_EXPR | |
3966 | && TREE_CODE (TREE_OPERAND (t, 1)) == code | |
459a2653 RK |
3967 | && TREE_CODE (TREE_OPERAND (t, 2)) == code |
3968 | && (TREE_TYPE (TREE_OPERAND (TREE_OPERAND (t, 1), 0)) | |
e1f56f62 RK |
3969 | == TREE_TYPE (TREE_OPERAND (TREE_OPERAND (t, 2), 0))) |
3970 | && ! (INTEGRAL_TYPE_P (TREE_TYPE (t)) | |
3971 | && INTEGRAL_TYPE_P (TREE_TYPE (TREE_OPERAND (TREE_OPERAND (t, 1), 0))) | |
3972 | && TYPE_PRECISION (TREE_TYPE (t)) <= BITS_PER_WORD)) | |
b8eb43a2 RK |
3973 | t = build1 (code, type, |
3974 | build (COND_EXPR, | |
3975 | TREE_TYPE (TREE_OPERAND (TREE_OPERAND (t, 1), 0)), | |
3976 | TREE_OPERAND (t, 0), | |
3977 | TREE_OPERAND (TREE_OPERAND (t, 1), 0), | |
3978 | TREE_OPERAND (TREE_OPERAND (t, 2), 0))); | |
3979 | return t; | |
3980 | } | |
6d716ca8 RS |
3981 | else if (TREE_CODE_CLASS (TREE_CODE (arg0)) == '<') |
3982 | return fold (build (COND_EXPR, type, arg0, | |
3983 | fold (build1 (code, type, integer_one_node)), | |
3984 | fold (build1 (code, type, integer_zero_node)))); | |
3985 | } | |
96d4cf0a RK |
3986 | else if (TREE_CODE_CLASS (code) == '2' |
3987 | || TREE_CODE_CLASS (code) == '<') | |
6d716ca8 RS |
3988 | { |
3989 | if (TREE_CODE (arg1) == COMPOUND_EXPR) | |
3990 | return build (COMPOUND_EXPR, type, TREE_OPERAND (arg1, 0), | |
96d4cf0a RK |
3991 | fold (build (code, type, |
3992 | arg0, TREE_OPERAND (arg1, 1)))); | |
f0eebf28 RK |
3993 | else if ((TREE_CODE (arg1) == COND_EXPR |
3994 | || (TREE_CODE_CLASS (TREE_CODE (arg1)) == '<' | |
3995 | && TREE_CODE_CLASS (code) != '<')) | |
9ec36da5 JL |
3996 | && (! TREE_SIDE_EFFECTS (arg0) |
3997 | || (current_function_decl != 0 | |
3998 | && ! contains_placeholder_p (arg0)))) | |
6d716ca8 RS |
3999 | { |
4000 | tree test, true_value, false_value; | |
f5963e61 | 4001 | tree lhs = 0, rhs = 0; |
6d716ca8 RS |
4002 | |
4003 | if (TREE_CODE (arg1) == COND_EXPR) | |
4004 | { | |
4005 | test = TREE_OPERAND (arg1, 0); | |
4006 | true_value = TREE_OPERAND (arg1, 1); | |
4007 | false_value = TREE_OPERAND (arg1, 2); | |
4008 | } | |
4009 | else | |
4010 | { | |
25216284 | 4011 | tree testtype = TREE_TYPE (arg1); |
6d716ca8 | 4012 | test = arg1; |
25216284 RK |
4013 | true_value = convert (testtype, integer_one_node); |
4014 | false_value = convert (testtype, integer_zero_node); | |
6d716ca8 RS |
4015 | } |
4016 | ||
96d4cf0a RK |
4017 | /* If ARG0 is complex we want to make sure we only evaluate |
4018 | it once. Though this is only required if it is volatile, it | |
4019 | might be more efficient even if it is not. However, if we | |
4020 | succeed in folding one part to a constant, we do not need | |
4021 | to make this SAVE_EXPR. Since we do this optimization | |
4022 | primarily to see if we do end up with constant and this | |
9faa82d8 | 4023 | SAVE_EXPR interferes with later optimizations, suppressing |
f5963e61 | 4024 | it when we can is important. |
96d4cf0a | 4025 | |
f5963e61 JL |
4026 | If we are not in a function, we can't make a SAVE_EXPR, so don't |
4027 | try to do so. Don't try to see if the result is a constant | |
4028 | if an arm is a COND_EXPR since we get exponential behavior | |
4029 | in that case. */ | |
4030 | ||
4031 | if (TREE_CODE (arg0) != SAVE_EXPR && ! TREE_CONSTANT (arg0) | |
4032 | && current_function_decl != 0 | |
b5f3b6b6 RK |
4033 | && ((TREE_CODE (arg0) != VAR_DECL |
4034 | && TREE_CODE (arg0) != PARM_DECL) | |
4035 | || TREE_SIDE_EFFECTS (arg0))) | |
96d4cf0a | 4036 | { |
f5963e61 JL |
4037 | if (TREE_CODE (true_value) != COND_EXPR) |
4038 | lhs = fold (build (code, type, arg0, true_value)); | |
96d4cf0a | 4039 | |
f5963e61 JL |
4040 | if (TREE_CODE (false_value) != COND_EXPR) |
4041 | rhs = fold (build (code, type, arg0, false_value)); | |
96d4cf0a | 4042 | |
f5963e61 JL |
4043 | if ((lhs == 0 || ! TREE_CONSTANT (lhs)) |
4044 | && (rhs == 0 || !TREE_CONSTANT (rhs))) | |
4045 | arg0 = save_expr (arg0), lhs = rhs = 0; | |
96d4cf0a RK |
4046 | } |
4047 | ||
f5963e61 JL |
4048 | if (lhs == 0) |
4049 | lhs = fold (build (code, type, arg0, true_value)); | |
4050 | if (rhs == 0) | |
4051 | rhs = fold (build (code, type, arg0, false_value)); | |
4052 | ||
4053 | test = fold (build (COND_EXPR, type, test, lhs, rhs)); | |
4054 | ||
6d716ca8 RS |
4055 | if (TREE_CODE (arg0) == SAVE_EXPR) |
4056 | return build (COMPOUND_EXPR, type, | |
b5f3b6b6 RK |
4057 | convert (void_type_node, arg0), |
4058 | strip_compound_expr (test, arg0)); | |
6d716ca8 RS |
4059 | else |
4060 | return convert (type, test); | |
4061 | } | |
4062 | ||
4063 | else if (TREE_CODE (arg0) == COMPOUND_EXPR) | |
4064 | return build (COMPOUND_EXPR, type, TREE_OPERAND (arg0, 0), | |
4065 | fold (build (code, type, TREE_OPERAND (arg0, 1), arg1))); | |
f0eebf28 RK |
4066 | else if ((TREE_CODE (arg0) == COND_EXPR |
4067 | || (TREE_CODE_CLASS (TREE_CODE (arg0)) == '<' | |
4068 | && TREE_CODE_CLASS (code) != '<')) | |
9ec36da5 JL |
4069 | && (! TREE_SIDE_EFFECTS (arg1) |
4070 | || (current_function_decl != 0 | |
4071 | && ! contains_placeholder_p (arg1)))) | |
6d716ca8 RS |
4072 | { |
4073 | tree test, true_value, false_value; | |
f5963e61 | 4074 | tree lhs = 0, rhs = 0; |
6d716ca8 RS |
4075 | |
4076 | if (TREE_CODE (arg0) == COND_EXPR) | |
4077 | { | |
4078 | test = TREE_OPERAND (arg0, 0); | |
4079 | true_value = TREE_OPERAND (arg0, 1); | |
4080 | false_value = TREE_OPERAND (arg0, 2); | |
4081 | } | |
4082 | else | |
4083 | { | |
25216284 | 4084 | tree testtype = TREE_TYPE (arg0); |
6d716ca8 | 4085 | test = arg0; |
25216284 RK |
4086 | true_value = convert (testtype, integer_one_node); |
4087 | false_value = convert (testtype, integer_zero_node); | |
6d716ca8 RS |
4088 | } |
4089 | ||
f5963e61 JL |
4090 | if (TREE_CODE (arg1) != SAVE_EXPR && ! TREE_CONSTANT (arg0) |
4091 | && current_function_decl != 0 | |
b5f3b6b6 RK |
4092 | && ((TREE_CODE (arg1) != VAR_DECL |
4093 | && TREE_CODE (arg1) != PARM_DECL) | |
4094 | || TREE_SIDE_EFFECTS (arg1))) | |
96d4cf0a | 4095 | { |
f5963e61 JL |
4096 | if (TREE_CODE (true_value) != COND_EXPR) |
4097 | lhs = fold (build (code, type, true_value, arg1)); | |
96d4cf0a | 4098 | |
f5963e61 JL |
4099 | if (TREE_CODE (false_value) != COND_EXPR) |
4100 | rhs = fold (build (code, type, false_value, arg1)); | |
96d4cf0a | 4101 | |
f5963e61 JL |
4102 | if ((lhs == 0 || ! TREE_CONSTANT (lhs)) |
4103 | && (rhs == 0 || !TREE_CONSTANT (rhs))) | |
4104 | arg1 = save_expr (arg1), lhs = rhs = 0; | |
96d4cf0a RK |
4105 | } |
4106 | ||
f5963e61 JL |
4107 | if (lhs == 0) |
4108 | lhs = fold (build (code, type, true_value, arg1)); | |
4109 | ||
4110 | if (rhs == 0) | |
4111 | rhs = fold (build (code, type, false_value, arg1)); | |
4112 | ||
4113 | test = fold (build (COND_EXPR, type, test, lhs, rhs)); | |
6d716ca8 RS |
4114 | if (TREE_CODE (arg1) == SAVE_EXPR) |
4115 | return build (COMPOUND_EXPR, type, | |
b5f3b6b6 RK |
4116 | convert (void_type_node, arg1), |
4117 | strip_compound_expr (test, arg1)); | |
6d716ca8 RS |
4118 | else |
4119 | return convert (type, test); | |
4120 | } | |
4121 | } | |
c05a9b68 RS |
4122 | else if (TREE_CODE_CLASS (code) == '<' |
4123 | && TREE_CODE (arg0) == COMPOUND_EXPR) | |
4124 | return build (COMPOUND_EXPR, type, TREE_OPERAND (arg0, 0), | |
4125 | fold (build (code, type, TREE_OPERAND (arg0, 1), arg1))); | |
4126 | else if (TREE_CODE_CLASS (code) == '<' | |
4127 | && TREE_CODE (arg1) == COMPOUND_EXPR) | |
4128 | return build (COMPOUND_EXPR, type, TREE_OPERAND (arg1, 0), | |
4129 | fold (build (code, type, arg0, TREE_OPERAND (arg1, 1)))); | |
6d716ca8 RS |
4130 | |
4131 | switch (code) | |
4132 | { | |
4133 | case INTEGER_CST: | |
4134 | case REAL_CST: | |
4135 | case STRING_CST: | |
4136 | case COMPLEX_CST: | |
4137 | case CONSTRUCTOR: | |
4138 | return t; | |
4139 | ||
4140 | case CONST_DECL: | |
4141 | return fold (DECL_INITIAL (t)); | |
4142 | ||
4143 | case NOP_EXPR: | |
4144 | case FLOAT_EXPR: | |
4145 | case CONVERT_EXPR: | |
4146 | case FIX_TRUNC_EXPR: | |
4147 | /* Other kinds of FIX are not handled properly by fold_convert. */ | |
33558beb | 4148 | |
e1f56f62 RK |
4149 | if (TREE_TYPE (TREE_OPERAND (t, 0)) == TREE_TYPE (t)) |
4150 | return TREE_OPERAND (t, 0); | |
4151 | ||
7e139075 RK |
4152 | /* Handle cases of two conversions in a row. */ |
4153 | if (TREE_CODE (TREE_OPERAND (t, 0)) == NOP_EXPR | |
4154 | || TREE_CODE (TREE_OPERAND (t, 0)) == CONVERT_EXPR) | |
4155 | { | |
4156 | tree inside_type = TREE_TYPE (TREE_OPERAND (TREE_OPERAND (t, 0), 0)); | |
4157 | tree inter_type = TREE_TYPE (TREE_OPERAND (t, 0)); | |
4158 | tree final_type = TREE_TYPE (t); | |
4159 | int inside_int = INTEGRAL_TYPE_P (inside_type); | |
7f0b305c | 4160 | int inside_ptr = POINTER_TYPE_P (inside_type); |
7e139075 RK |
4161 | int inside_float = FLOAT_TYPE_P (inside_type); |
4162 | int inside_prec = TYPE_PRECISION (inside_type); | |
4163 | int inside_unsignedp = TREE_UNSIGNED (inside_type); | |
4164 | int inter_int = INTEGRAL_TYPE_P (inter_type); | |
7f0b305c | 4165 | int inter_ptr = POINTER_TYPE_P (inter_type); |
7e139075 RK |
4166 | int inter_float = FLOAT_TYPE_P (inter_type); |
4167 | int inter_prec = TYPE_PRECISION (inter_type); | |
4168 | int inter_unsignedp = TREE_UNSIGNED (inter_type); | |
4169 | int final_int = INTEGRAL_TYPE_P (final_type); | |
7f0b305c | 4170 | int final_ptr = POINTER_TYPE_P (final_type); |
7e139075 RK |
4171 | int final_float = FLOAT_TYPE_P (final_type); |
4172 | int final_prec = TYPE_PRECISION (final_type); | |
4173 | int final_unsignedp = TREE_UNSIGNED (final_type); | |
4174 | ||
4175 | /* In addition to the cases of two conversions in a row | |
4176 | handled below, if we are converting something to its own | |
4177 | type via an object of identical or wider precision, neither | |
4178 | conversion is needed. */ | |
4179 | if (inside_type == final_type | |
4180 | && ((inter_int && final_int) || (inter_float && final_float)) | |
4181 | && inter_prec >= final_prec) | |
4182 | return TREE_OPERAND (TREE_OPERAND (t, 0), 0); | |
4183 | ||
4184 | /* Likewise, if the intermediate and final types are either both | |
4185 | float or both integer, we don't need the middle conversion if | |
4186 | it is wider than the final type and doesn't change the signedness | |
7f0b305c | 4187 | (for integers). Avoid this if the final type is a pointer |
410d3f5d RK |
4188 | since then we sometimes need the inner conversion. Likewise if |
4189 | the outer has a precision not equal to the size of its mode. */ | |
7e139075 RK |
4190 | if ((((inter_int || inter_ptr) && (inside_int || inside_ptr)) |
4191 | || (inter_float && inside_float)) | |
4192 | && inter_prec >= inside_prec | |
7f0b305c | 4193 | && (inter_float || inter_unsignedp == inside_unsignedp) |
410d3f5d RK |
4194 | && ! (final_prec != GET_MODE_BITSIZE (TYPE_MODE (final_type)) |
4195 | && TYPE_MODE (final_type) == TYPE_MODE (inter_type)) | |
7f0b305c | 4196 | && ! final_ptr) |
7e139075 RK |
4197 | return convert (final_type, TREE_OPERAND (TREE_OPERAND (t, 0), 0)); |
4198 | ||
ba3ad5e0 PDM |
4199 | /* If we have a sign-extension of a zero-extended value, we can |
4200 | replace that by a single zero-extension. */ | |
4201 | if (inside_int && inter_int && final_int | |
4202 | && inside_prec < inter_prec && inter_prec < final_prec | |
4203 | && inside_unsignedp && !inter_unsignedp) | |
4204 | return convert (final_type, TREE_OPERAND (TREE_OPERAND (t, 0), 0)); | |
4205 | ||
7e139075 RK |
4206 | /* Two conversions in a row are not needed unless: |
4207 | - some conversion is floating-point (overstrict for now), or | |
4208 | - the intermediate type is narrower than both initial and | |
4209 | final, or | |
4210 | - the intermediate type and innermost type differ in signedness, | |
4211 | and the outermost type is wider than the intermediate, or | |
4212 | - the initial type is a pointer type and the precisions of the | |
4213 | intermediate and final types differ, or | |
4214 | - the final type is a pointer type and the precisions of the | |
4215 | initial and intermediate types differ. */ | |
4216 | if (! inside_float && ! inter_float && ! final_float | |
4217 | && (inter_prec > inside_prec || inter_prec > final_prec) | |
4218 | && ! (inside_int && inter_int | |
4219 | && inter_unsignedp != inside_unsignedp | |
4220 | && inter_prec < final_prec) | |
4221 | && ((inter_unsignedp && inter_prec > inside_prec) | |
4222 | == (final_unsignedp && final_prec > inter_prec)) | |
4223 | && ! (inside_ptr && inter_prec != final_prec) | |
410d3f5d RK |
4224 | && ! (final_ptr && inside_prec != inter_prec) |
4225 | && ! (final_prec != GET_MODE_BITSIZE (TYPE_MODE (final_type)) | |
4226 | && TYPE_MODE (final_type) == TYPE_MODE (inter_type)) | |
4227 | && ! final_ptr) | |
7e139075 RK |
4228 | return convert (final_type, TREE_OPERAND (TREE_OPERAND (t, 0), 0)); |
4229 | } | |
6d716ca8 RS |
4230 | |
4231 | if (TREE_CODE (TREE_OPERAND (t, 0)) == MODIFY_EXPR | |
d8f6dbb9 RS |
4232 | && TREE_CONSTANT (TREE_OPERAND (TREE_OPERAND (t, 0), 1)) |
4233 | /* Detect assigning a bitfield. */ | |
4234 | && !(TREE_CODE (TREE_OPERAND (TREE_OPERAND (t, 0), 0)) == COMPONENT_REF | |
4235 | && DECL_BIT_FIELD (TREE_OPERAND (TREE_OPERAND (TREE_OPERAND (t, 0), 0), 1)))) | |
6d716ca8 | 4236 | { |
d8f6dbb9 | 4237 | /* Don't leave an assignment inside a conversion |
f72aed24 | 4238 | unless assigning a bitfield. */ |
6d716ca8 RS |
4239 | tree prev = TREE_OPERAND (t, 0); |
4240 | TREE_OPERAND (t, 0) = TREE_OPERAND (prev, 1); | |
4241 | /* First do the assignment, then return converted constant. */ | |
4242 | t = build (COMPOUND_EXPR, TREE_TYPE (t), prev, fold (t)); | |
4243 | TREE_USED (t) = 1; | |
4244 | return t; | |
4245 | } | |
4246 | if (!wins) | |
4247 | { | |
4248 | TREE_CONSTANT (t) = TREE_CONSTANT (arg0); | |
4249 | return t; | |
4250 | } | |
4251 | return fold_convert (t, arg0); | |
4252 | ||
4253 | #if 0 /* This loses on &"foo"[0]. */ | |
4254 | case ARRAY_REF: | |
4255 | { | |
4256 | int i; | |
4257 | ||
4258 | /* Fold an expression like: "foo"[2] */ | |
4259 | if (TREE_CODE (arg0) == STRING_CST | |
4260 | && TREE_CODE (arg1) == INTEGER_CST | |
4261 | && !TREE_INT_CST_HIGH (arg1) | |
4262 | && (i = TREE_INT_CST_LOW (arg1)) < TREE_STRING_LENGTH (arg0)) | |
4263 | { | |
4264 | t = build_int_2 (TREE_STRING_POINTER (arg0)[i], 0); | |
4265 | TREE_TYPE (t) = TREE_TYPE (TREE_TYPE (arg0)); | |
ef2bf0c0 | 4266 | force_fit_type (t, 0); |
6d716ca8 RS |
4267 | } |
4268 | } | |
4269 | return t; | |
4270 | #endif /* 0 */ | |
4271 | ||
e082358b JM |
4272 | case COMPONENT_REF: |
4273 | if (TREE_CODE (arg0) == CONSTRUCTOR) | |
3ac4f0e6 JM |
4274 | { |
4275 | tree m = purpose_member (arg1, CONSTRUCTOR_ELTS (arg0)); | |
4276 | if (m) | |
4277 | t = TREE_VALUE (m); | |
4278 | } | |
e082358b JM |
4279 | return t; |
4280 | ||
6d716ca8 RS |
4281 | case RANGE_EXPR: |
4282 | TREE_CONSTANT (t) = wins; | |
4283 | return t; | |
4284 | ||
4285 | case NEGATE_EXPR: | |
4286 | if (wins) | |
4287 | { | |
4288 | if (TREE_CODE (arg0) == INTEGER_CST) | |
4289 | { | |
fe3e8e40 RS |
4290 | HOST_WIDE_INT low, high; |
4291 | int overflow = neg_double (TREE_INT_CST_LOW (arg0), | |
4292 | TREE_INT_CST_HIGH (arg0), | |
4293 | &low, &high); | |
4294 | t = build_int_2 (low, high); | |
6d716ca8 | 4295 | TREE_TYPE (t) = type; |
dc3907c5 PE |
4296 | TREE_OVERFLOW (t) |
4297 | = (TREE_OVERFLOW (arg0) | |
0c9cabe7 | 4298 | | force_fit_type (t, overflow && !TREE_UNSIGNED (type))); |
dc3907c5 PE |
4299 | TREE_CONSTANT_OVERFLOW (t) |
4300 | = TREE_OVERFLOW (t) | TREE_CONSTANT_OVERFLOW (arg0); | |
6d716ca8 RS |
4301 | } |
4302 | else if (TREE_CODE (arg0) == REAL_CST) | |
4303 | t = build_real (type, REAL_VALUE_NEGATE (TREE_REAL_CST (arg0))); | |
6d716ca8 RS |
4304 | } |
4305 | else if (TREE_CODE (arg0) == NEGATE_EXPR) | |
4306 | return TREE_OPERAND (arg0, 0); | |
4307 | ||
4308 | /* Convert - (a - b) to (b - a) for non-floating-point. */ | |
7178e3af | 4309 | else if (TREE_CODE (arg0) == MINUS_EXPR && ! FLOAT_TYPE_P (type)) |
6d716ca8 RS |
4310 | return build (MINUS_EXPR, type, TREE_OPERAND (arg0, 1), |
4311 | TREE_OPERAND (arg0, 0)); | |
4312 | ||
4313 | return t; | |
4314 | ||
4315 | case ABS_EXPR: | |
4316 | if (wins) | |
4317 | { | |
4318 | if (TREE_CODE (arg0) == INTEGER_CST) | |
4319 | { | |
4320 | if (! TREE_UNSIGNED (type) | |
4321 | && TREE_INT_CST_HIGH (arg0) < 0) | |
4322 | { | |
2a23183e RS |
4323 | HOST_WIDE_INT low, high; |
4324 | int overflow = neg_double (TREE_INT_CST_LOW (arg0), | |
4325 | TREE_INT_CST_HIGH (arg0), | |
4326 | &low, &high); | |
4327 | t = build_int_2 (low, high); | |
4328 | TREE_TYPE (t) = type; | |
dc3907c5 PE |
4329 | TREE_OVERFLOW (t) |
4330 | = (TREE_OVERFLOW (arg0) | |
e0f776fb | 4331 | | force_fit_type (t, overflow)); |
dc3907c5 PE |
4332 | TREE_CONSTANT_OVERFLOW (t) |
4333 | = TREE_OVERFLOW (t) | TREE_CONSTANT_OVERFLOW (arg0); | |
6d716ca8 RS |
4334 | } |
4335 | } | |
4336 | else if (TREE_CODE (arg0) == REAL_CST) | |
4337 | { | |
c05a9b68 | 4338 | if (REAL_VALUE_NEGATIVE (TREE_REAL_CST (arg0))) |
6d716ca8 RS |
4339 | t = build_real (type, |
4340 | REAL_VALUE_NEGATE (TREE_REAL_CST (arg0))); | |
4341 | } | |
6d716ca8 RS |
4342 | } |
4343 | else if (TREE_CODE (arg0) == ABS_EXPR || TREE_CODE (arg0) == NEGATE_EXPR) | |
4344 | return build1 (ABS_EXPR, type, TREE_OPERAND (arg0, 0)); | |
4345 | return t; | |
4346 | ||
551064b1 RS |
4347 | case CONJ_EXPR: |
4348 | if (TREE_CODE (TREE_TYPE (arg0)) != COMPLEX_TYPE) | |
4349 | return arg0; | |
4350 | else if (TREE_CODE (arg0) == COMPLEX_EXPR) | |
4351 | return build (COMPLEX_EXPR, TREE_TYPE (arg0), | |
4352 | TREE_OPERAND (arg0, 0), | |
4353 | fold (build1 (NEGATE_EXPR, | |
4354 | TREE_TYPE (TREE_TYPE (arg0)), | |
4355 | TREE_OPERAND (arg0, 1)))); | |
4356 | else if (TREE_CODE (arg0) == COMPLEX_CST) | |
214d5b84 | 4357 | return build_complex (type, TREE_OPERAND (arg0, 0), |
551064b1 RS |
4358 | fold (build1 (NEGATE_EXPR, |
4359 | TREE_TYPE (TREE_TYPE (arg0)), | |
4360 | TREE_OPERAND (arg0, 1)))); | |
4361 | else if (TREE_CODE (arg0) == PLUS_EXPR || TREE_CODE (arg0) == MINUS_EXPR) | |
4362 | return fold (build (TREE_CODE (arg0), type, | |
4363 | fold (build1 (CONJ_EXPR, type, | |
4364 | TREE_OPERAND (arg0, 0))), | |
4365 | fold (build1 (CONJ_EXPR, | |
4366 | type, TREE_OPERAND (arg0, 1))))); | |
4367 | else if (TREE_CODE (arg0) == CONJ_EXPR) | |
4368 | return TREE_OPERAND (arg0, 0); | |
4369 | return t; | |
4370 | ||
6d716ca8 RS |
4371 | case BIT_NOT_EXPR: |
4372 | if (wins) | |
4373 | { | |
380ff34a RK |
4374 | t = build_int_2 (~ TREE_INT_CST_LOW (arg0), |
4375 | ~ TREE_INT_CST_HIGH (arg0)); | |
6d716ca8 | 4376 | TREE_TYPE (t) = type; |
e0f776fb | 4377 | force_fit_type (t, 0); |
dc3907c5 | 4378 | TREE_OVERFLOW (t) = TREE_OVERFLOW (arg0); |
fe3e8e40 | 4379 | TREE_CONSTANT_OVERFLOW (t) = TREE_CONSTANT_OVERFLOW (arg0); |
6d716ca8 RS |
4380 | } |
4381 | else if (TREE_CODE (arg0) == BIT_NOT_EXPR) | |
4382 | return TREE_OPERAND (arg0, 0); | |
4383 | return t; | |
4384 | ||
4385 | case PLUS_EXPR: | |
4386 | /* A + (-B) -> A - B */ | |
4387 | if (TREE_CODE (arg1) == NEGATE_EXPR) | |
4388 | return fold (build (MINUS_EXPR, type, arg0, TREE_OPERAND (arg1, 0))); | |
7178e3af | 4389 | else if (! FLOAT_TYPE_P (type)) |
6d716ca8 RS |
4390 | { |
4391 | if (integer_zerop (arg1)) | |
4392 | return non_lvalue (convert (type, arg0)); | |
4393 | ||
4394 | /* If we are adding two BIT_AND_EXPR's, both of which are and'ing | |
4395 | with a constant, and the two constants have no bits in common, | |
4396 | we should treat this as a BIT_IOR_EXPR since this may produce more | |
4397 | simplifications. */ | |
4398 | if (TREE_CODE (arg0) == BIT_AND_EXPR | |
4399 | && TREE_CODE (arg1) == BIT_AND_EXPR | |
4400 | && TREE_CODE (TREE_OPERAND (arg0, 1)) == INTEGER_CST | |
4401 | && TREE_CODE (TREE_OPERAND (arg1, 1)) == INTEGER_CST | |
4402 | && integer_zerop (const_binop (BIT_AND_EXPR, | |
4403 | TREE_OPERAND (arg0, 1), | |
91d33e36 | 4404 | TREE_OPERAND (arg1, 1), 0))) |
6d716ca8 RS |
4405 | { |
4406 | code = BIT_IOR_EXPR; | |
4407 | goto bit_ior; | |
4408 | } | |
6a96fcb4 | 4409 | |
45f97e2e RH |
4410 | if (TREE_CODE (arg0) == MULT_EXPR && TREE_CODE (arg1) == MULT_EXPR) |
4411 | { | |
4412 | tree arg00, arg01, arg10, arg11; | |
4413 | tree alt0, alt1, same; | |
4414 | ||
4415 | /* (A * C) + (B * C) -> (A+B) * C. | |
4416 | We are most concerned about the case where C is a constant, | |
4417 | but other combinations show up during loop reduction. Since | |
4418 | it is not difficult, try all four possibilities. */ | |
4419 | ||
4420 | arg00 = TREE_OPERAND (arg0, 0); | |
4421 | arg01 = TREE_OPERAND (arg0, 1); | |
4422 | arg10 = TREE_OPERAND (arg1, 0); | |
4423 | arg11 = TREE_OPERAND (arg1, 1); | |
4424 | same = NULL_TREE; | |
4425 | ||
4426 | if (operand_equal_p (arg01, arg11, 0)) | |
4427 | same = arg01, alt0 = arg00, alt1 = arg10; | |
4428 | else if (operand_equal_p (arg00, arg10, 0)) | |
4429 | same = arg00, alt0 = arg01, alt1 = arg11; | |
4430 | else if (operand_equal_p (arg00, arg11, 0)) | |
4431 | same = arg00, alt0 = arg01, alt1 = arg10; | |
4432 | else if (operand_equal_p (arg01, arg10, 0)) | |
4433 | same = arg01, alt0 = arg00, alt1 = arg11; | |
4434 | ||
4435 | if (same) | |
4436 | return fold (build (MULT_EXPR, type, | |
4437 | fold (build (PLUS_EXPR, type, alt0, alt1)), | |
4438 | same)); | |
4439 | } | |
6d716ca8 RS |
4440 | } |
4441 | /* In IEEE floating point, x+0 may not equal x. */ | |
996c63d3 RK |
4442 | else if ((TARGET_FLOAT_FORMAT != IEEE_FLOAT_FORMAT |
4443 | || flag_fast_math) | |
6d716ca8 RS |
4444 | && real_zerop (arg1)) |
4445 | return non_lvalue (convert (type, arg0)); | |
4446 | associate: | |
4447 | /* In most languages, can't associate operations on floats | |
4448 | through parentheses. Rather than remember where the parentheses | |
e9aaa5a5 RK |
4449 | were, we don't associate floats at all. It shouldn't matter much. |
4450 | However, associating multiplications is only very slightly | |
4451 | inaccurate, so do that if -ffast-math is specified. */ | |
4452 | if (FLOAT_TYPE_P (type) | |
4453 | && ! (flag_fast_math && code == MULT_EXPR)) | |
6d716ca8 | 4454 | goto binary; |
e9aaa5a5 | 4455 | |
6d716ca8 RS |
4456 | /* The varsign == -1 cases happen only for addition and subtraction. |
4457 | It says that the arg that was split was really CON minus VAR. | |
4458 | The rest of the code applies to all associative operations. */ | |
4459 | if (!wins) | |
4460 | { | |
c05a9b68 | 4461 | tree var, con; |
6d716ca8 RS |
4462 | int varsign; |
4463 | ||
4464 | if (split_tree (arg0, code, &var, &con, &varsign)) | |
4465 | { | |
4466 | if (varsign == -1) | |
4467 | { | |
4468 | /* EXPR is (CON-VAR) +- ARG1. */ | |
4469 | /* If it is + and VAR==ARG1, return just CONST. */ | |
4470 | if (code == PLUS_EXPR && operand_equal_p (var, arg1, 0)) | |
4471 | return convert (TREE_TYPE (t), con); | |
4472 | ||
ca86a57a | 4473 | /* If ARG0 is a constant, don't change things around; |
77a45a2e | 4474 | instead keep all the constant computations together. */ |
ca86a57a | 4475 | |
77a45a2e | 4476 | if (TREE_CONSTANT (arg0)) |
ca86a57a RK |
4477 | return t; |
4478 | ||
6d716ca8 | 4479 | /* Otherwise return (CON +- ARG1) - VAR. */ |
cd7ece66 RK |
4480 | t = build (MINUS_EXPR, type, |
4481 | fold (build (code, type, con, arg1)), var); | |
6d716ca8 RS |
4482 | } |
4483 | else | |
4484 | { | |
4485 | /* EXPR is (VAR+CON) +- ARG1. */ | |
4486 | /* If it is - and VAR==ARG1, return just CONST. */ | |
4487 | if (code == MINUS_EXPR && operand_equal_p (var, arg1, 0)) | |
4488 | return convert (TREE_TYPE (t), con); | |
4489 | ||
ca86a57a | 4490 | /* If ARG0 is a constant, don't change things around; |
77a45a2e | 4491 | instead keep all the constant computations together. */ |
ca86a57a | 4492 | |
77a45a2e | 4493 | if (TREE_CONSTANT (arg0)) |
ca86a57a RK |
4494 | return t; |
4495 | ||
6d716ca8 | 4496 | /* Otherwise return VAR +- (ARG1 +- CON). */ |
cd7ece66 RK |
4497 | tem = fold (build (code, type, arg1, con)); |
4498 | t = build (code, type, var, tem); | |
4499 | ||
6d716ca8 RS |
4500 | if (integer_zerop (tem) |
4501 | && (code == PLUS_EXPR || code == MINUS_EXPR)) | |
4502 | return convert (type, var); | |
4503 | /* If we have x +/- (c - d) [c an explicit integer] | |
4504 | change it to x -/+ (d - c) since if d is relocatable | |
4505 | then the latter can be a single immediate insn | |
4506 | and the former cannot. */ | |
4507 | if (TREE_CODE (tem) == MINUS_EXPR | |
4508 | && TREE_CODE (TREE_OPERAND (tem, 0)) == INTEGER_CST) | |
4509 | { | |
4510 | tree tem1 = TREE_OPERAND (tem, 1); | |
4511 | TREE_OPERAND (tem, 1) = TREE_OPERAND (tem, 0); | |
4512 | TREE_OPERAND (tem, 0) = tem1; | |
4513 | TREE_SET_CODE (t, | |
4514 | (code == PLUS_EXPR ? MINUS_EXPR : PLUS_EXPR)); | |
4515 | } | |
4516 | } | |
4517 | return t; | |
4518 | } | |
4519 | ||
4520 | if (split_tree (arg1, code, &var, &con, &varsign)) | |
4521 | { | |
77a45a2e | 4522 | if (TREE_CONSTANT (arg1)) |
cc5edac6 RK |
4523 | return t; |
4524 | ||
4525 | if (varsign == -1) | |
4526 | TREE_SET_CODE (t, | |
4527 | (code == PLUS_EXPR ? MINUS_EXPR : PLUS_EXPR)); | |
4528 | ||
6d716ca8 | 4529 | /* EXPR is ARG0 +- (CON +- VAR). */ |
6d716ca8 RS |
4530 | if (TREE_CODE (t) == MINUS_EXPR |
4531 | && operand_equal_p (var, arg0, 0)) | |
4532 | { | |
4533 | /* If VAR and ARG0 cancel, return just CON or -CON. */ | |
4534 | if (code == PLUS_EXPR) | |
4535 | return convert (TREE_TYPE (t), con); | |
4536 | return fold (build1 (NEGATE_EXPR, TREE_TYPE (t), | |
4537 | convert (TREE_TYPE (t), con))); | |
4538 | } | |
cc5edac6 | 4539 | |
cd7ece66 RK |
4540 | t = build (TREE_CODE (t), type, |
4541 | fold (build (code, TREE_TYPE (t), arg0, con)), var); | |
4542 | ||
6d716ca8 RS |
4543 | if (integer_zerop (TREE_OPERAND (t, 0)) |
4544 | && TREE_CODE (t) == PLUS_EXPR) | |
4545 | return convert (TREE_TYPE (t), var); | |
4546 | return t; | |
4547 | } | |
4548 | } | |
4549 | binary: | |
4550 | #if defined (REAL_IS_NOT_DOUBLE) && ! defined (REAL_ARITHMETIC) | |
4551 | if (TREE_CODE (arg1) == REAL_CST) | |
4552 | return t; | |
4553 | #endif /* REAL_IS_NOT_DOUBLE, and no REAL_ARITHMETIC */ | |
4554 | if (wins) | |
91d33e36 | 4555 | t1 = const_binop (code, arg0, arg1, 0); |
6d716ca8 RS |
4556 | if (t1 != NULL_TREE) |
4557 | { | |
4558 | /* The return value should always have | |
4559 | the same type as the original expression. */ | |
380ff34a RK |
4560 | if (TREE_TYPE (t1) != TREE_TYPE (t)) |
4561 | t1 = convert (TREE_TYPE (t), t1); | |
4562 | ||
6d716ca8 RS |
4563 | return t1; |
4564 | } | |
4565 | return t; | |
4566 | ||
4567 | case MINUS_EXPR: | |
7178e3af | 4568 | if (! FLOAT_TYPE_P (type)) |
6d716ca8 RS |
4569 | { |
4570 | if (! wins && integer_zerop (arg0)) | |
4571 | return build1 (NEGATE_EXPR, type, arg1); | |
4572 | if (integer_zerop (arg1)) | |
4573 | return non_lvalue (convert (type, arg0)); | |
6a96fcb4 RK |
4574 | |
4575 | /* (A * C) - (B * C) -> (A-B) * C. Since we are most concerned | |
4576 | about the case where C is a constant, just try one of the | |
4577 | four possibilities. */ | |
4578 | ||
4579 | if (TREE_CODE (arg0) == MULT_EXPR && TREE_CODE (arg1) == MULT_EXPR | |
4580 | && operand_equal_p (TREE_OPERAND (arg0, 1), | |
4581 | TREE_OPERAND (arg1, 1), 0)) | |
4582 | return fold (build (MULT_EXPR, type, | |
4583 | fold (build (MINUS_EXPR, type, | |
4584 | TREE_OPERAND (arg0, 0), | |
4585 | TREE_OPERAND (arg1, 0))), | |
4586 | TREE_OPERAND (arg0, 1))); | |
6d716ca8 RS |
4587 | } |
4588 | /* Convert A - (-B) to A + B. */ | |
4589 | else if (TREE_CODE (arg1) == NEGATE_EXPR) | |
4590 | return fold (build (PLUS_EXPR, type, arg0, TREE_OPERAND (arg1, 0))); | |
fab446b8 RK |
4591 | |
4592 | else if (TARGET_FLOAT_FORMAT != IEEE_FLOAT_FORMAT | |
4593 | || flag_fast_math) | |
6d716ca8 | 4594 | { |
c05a9b68 | 4595 | /* Except with IEEE floating point, 0-x equals -x. */ |
6d716ca8 RS |
4596 | if (! wins && real_zerop (arg0)) |
4597 | return build1 (NEGATE_EXPR, type, arg1); | |
c05a9b68 RS |
4598 | /* Except with IEEE floating point, x-0 equals x. */ |
4599 | if (real_zerop (arg1)) | |
6d716ca8 | 4600 | return non_lvalue (convert (type, arg0)); |
fab446b8 | 4601 | } |
a6acbe15 | 4602 | |
fab446b8 RK |
4603 | /* Fold &x - &x. This can happen from &x.foo - &x. |
4604 | This is unsafe for certain floats even in non-IEEE formats. | |
4605 | In IEEE, it is unsafe because it does wrong for NaNs. | |
4606 | Also note that operand_equal_p is always false if an operand | |
4607 | is volatile. */ | |
4608 | ||
59d90212 JW |
4609 | if ((! FLOAT_TYPE_P (type) || flag_fast_math) |
4610 | && operand_equal_p (arg0, arg1, 0)) | |
fab446b8 | 4611 | return convert (type, integer_zero_node); |
a6acbe15 | 4612 | |
6d716ca8 RS |
4613 | goto associate; |
4614 | ||
4615 | case MULT_EXPR: | |
7178e3af | 4616 | if (! FLOAT_TYPE_P (type)) |
6d716ca8 RS |
4617 | { |
4618 | if (integer_zerop (arg1)) | |
4619 | return omit_one_operand (type, arg1, arg0); | |
4620 | if (integer_onep (arg1)) | |
4621 | return non_lvalue (convert (type, arg0)); | |
4622 | ||
b9b5c1b3 RK |
4623 | /* ((A / C) * C) is A if the division is an |
4624 | EXACT_DIV_EXPR. Since C is normally a constant, | |
4625 | just check for one of the four possibilities. */ | |
4626 | ||
4627 | if (TREE_CODE (arg0) == EXACT_DIV_EXPR | |
4628 | && operand_equal_p (TREE_OPERAND (arg0, 1), arg1, 0)) | |
4629 | return TREE_OPERAND (arg0, 0); | |
4630 | ||
6d716ca8 RS |
4631 | /* (a * (1 << b)) is (a << b) */ |
4632 | if (TREE_CODE (arg1) == LSHIFT_EXPR | |
4633 | && integer_onep (TREE_OPERAND (arg1, 0))) | |
4634 | return fold (build (LSHIFT_EXPR, type, arg0, | |
4635 | TREE_OPERAND (arg1, 1))); | |
4636 | if (TREE_CODE (arg0) == LSHIFT_EXPR | |
4637 | && integer_onep (TREE_OPERAND (arg0, 0))) | |
4638 | return fold (build (LSHIFT_EXPR, type, arg1, | |
4639 | TREE_OPERAND (arg0, 1))); | |
4640 | } | |
6d716ca8 RS |
4641 | else |
4642 | { | |
c05a9b68 | 4643 | /* x*0 is 0, except for IEEE floating point. */ |
fab446b8 RK |
4644 | if ((TARGET_FLOAT_FORMAT != IEEE_FLOAT_FORMAT |
4645 | || flag_fast_math) | |
6d716ca8 RS |
4646 | && real_zerop (arg1)) |
4647 | return omit_one_operand (type, arg1, arg0); | |
c05a9b68 | 4648 | /* In IEEE floating point, x*1 is not equivalent to x for snans. |
6d716ca8 RS |
4649 | However, ANSI says we can drop signals, |
4650 | so we can do this anyway. */ | |
4651 | if (real_onep (arg1)) | |
4652 | return non_lvalue (convert (type, arg0)); | |
4653 | /* x*2 is x+x */ | |
9ec36da5 JL |
4654 | if (! wins && real_twop (arg1) && current_function_decl != 0 |
4655 | && ! contains_placeholder_p (arg0)) | |
6d716ca8 RS |
4656 | { |
4657 | tree arg = save_expr (arg0); | |
4658 | return build (PLUS_EXPR, type, arg, arg); | |
4659 | } | |
4660 | } | |
4661 | goto associate; | |
4662 | ||
4663 | case BIT_IOR_EXPR: | |
4664 | bit_ior: | |
65d8b1ce RK |
4665 | { |
4666 | register enum tree_code code0, code1; | |
4667 | ||
6d716ca8 RS |
4668 | if (integer_all_onesp (arg1)) |
4669 | return omit_one_operand (type, arg1, arg0); | |
4670 | if (integer_zerop (arg1)) | |
4671 | return non_lvalue (convert (type, arg0)); | |
4672 | t1 = distribute_bit_expr (code, type, arg0, arg1); | |
4673 | if (t1 != NULL_TREE) | |
4674 | return t1; | |
85d2e16c | 4675 | |
65d8b1ce | 4676 | /* (A << C1) | (A >> C2) if A is unsigned and C1+C2 is the size of A |
85d2e16c | 4677 | is a rotate of A by C1 bits. */ |
65d8b1ce RK |
4678 | /* (A << B) | (A >> (Z - B)) if A is unsigned and Z is the size of A |
4679 | is a rotate of A by B bits. */ | |
85d2e16c | 4680 | |
65d8b1ce RK |
4681 | code0 = TREE_CODE (arg0); |
4682 | code1 = TREE_CODE (arg1); | |
4683 | if (((code0 == RSHIFT_EXPR && code1 == LSHIFT_EXPR) | |
4684 | || (code1 == RSHIFT_EXPR && code0 == LSHIFT_EXPR)) | |
85d2e16c | 4685 | && operand_equal_p (TREE_OPERAND (arg0, 0), TREE_OPERAND (arg1,0), 0) |
65d8b1ce RK |
4686 | && TREE_UNSIGNED (TREE_TYPE (TREE_OPERAND (arg0, 0)))) |
4687 | { | |
4688 | register tree tree01, tree11; | |
4689 | register enum tree_code code01, code11; | |
4690 | ||
4691 | tree01 = TREE_OPERAND (arg0, 1); | |
4692 | tree11 = TREE_OPERAND (arg1, 1); | |
4693 | code01 = TREE_CODE (tree01); | |
4694 | code11 = TREE_CODE (tree11); | |
4695 | if (code01 == INTEGER_CST | |
4696 | && code11 == INTEGER_CST | |
4697 | && TREE_INT_CST_HIGH (tree01) == 0 | |
4698 | && TREE_INT_CST_HIGH (tree11) == 0 | |
4699 | && ((TREE_INT_CST_LOW (tree01) + TREE_INT_CST_LOW (tree11)) | |
85d2e16c | 4700 | == TYPE_PRECISION (TREE_TYPE (TREE_OPERAND (arg0, 0))))) |
65d8b1ce RK |
4701 | return build (LROTATE_EXPR, type, TREE_OPERAND (arg0, 0), |
4702 | code0 == LSHIFT_EXPR ? tree01 : tree11); | |
4703 | else if (code11 == MINUS_EXPR | |
4704 | && TREE_CODE (TREE_OPERAND (tree11, 0)) == INTEGER_CST | |
4705 | && TREE_INT_CST_HIGH (TREE_OPERAND (tree11, 0)) == 0 | |
4706 | && TREE_INT_CST_LOW (TREE_OPERAND (tree11, 0)) | |
4707 | == TYPE_PRECISION (TREE_TYPE (TREE_OPERAND (arg0, 0))) | |
4708 | && operand_equal_p (tree01, TREE_OPERAND (tree11, 1), 0)) | |
4709 | return build (code0 == LSHIFT_EXPR ? LROTATE_EXPR : RROTATE_EXPR, | |
4710 | type, TREE_OPERAND (arg0, 0), tree01); | |
4711 | else if (code01 == MINUS_EXPR | |
4712 | && TREE_CODE (TREE_OPERAND (tree01, 0)) == INTEGER_CST | |
4713 | && TREE_INT_CST_HIGH (TREE_OPERAND (tree01, 0)) == 0 | |
4714 | && TREE_INT_CST_LOW (TREE_OPERAND (tree01, 0)) | |
4715 | == TYPE_PRECISION (TREE_TYPE (TREE_OPERAND (arg0, 0))) | |
4716 | && operand_equal_p (tree11, TREE_OPERAND (tree01, 1), 0)) | |
4717 | return build (code0 != LSHIFT_EXPR ? LROTATE_EXPR : RROTATE_EXPR, | |
4718 | type, TREE_OPERAND (arg0, 0), tree11); | |
4719 | } | |
85d2e16c | 4720 | |
6d716ca8 | 4721 | goto associate; |
65d8b1ce | 4722 | } |
6d716ca8 RS |
4723 | |
4724 | case BIT_XOR_EXPR: | |
4725 | if (integer_zerop (arg1)) | |
4726 | return non_lvalue (convert (type, arg0)); | |
4727 | if (integer_all_onesp (arg1)) | |
4728 | return fold (build1 (BIT_NOT_EXPR, type, arg0)); | |
4729 | goto associate; | |
4730 | ||
4731 | case BIT_AND_EXPR: | |
4732 | bit_and: | |
4733 | if (integer_all_onesp (arg1)) | |
4734 | return non_lvalue (convert (type, arg0)); | |
4735 | if (integer_zerop (arg1)) | |
4736 | return omit_one_operand (type, arg1, arg0); | |
4737 | t1 = distribute_bit_expr (code, type, arg0, arg1); | |
4738 | if (t1 != NULL_TREE) | |
4739 | return t1; | |
4740 | /* Simplify ((int)c & 0x377) into (int)c, if c is unsigned char. */ | |
4741 | if (TREE_CODE (arg0) == INTEGER_CST && TREE_CODE (arg1) == NOP_EXPR | |
4742 | && TREE_UNSIGNED (TREE_TYPE (TREE_OPERAND (arg1, 0)))) | |
4743 | { | |
4744 | int prec = TYPE_PRECISION (TREE_TYPE (TREE_OPERAND (arg1, 0))); | |
906c4e36 RK |
4745 | if (prec < BITS_PER_WORD && prec < HOST_BITS_PER_WIDE_INT |
4746 | && (~TREE_INT_CST_LOW (arg0) | |
4747 | & (((HOST_WIDE_INT) 1 << prec) - 1)) == 0) | |
6d716ca8 RS |
4748 | return build1 (NOP_EXPR, type, TREE_OPERAND (arg1, 0)); |
4749 | } | |
4750 | if (TREE_CODE (arg1) == INTEGER_CST && TREE_CODE (arg0) == NOP_EXPR | |
4751 | && TREE_UNSIGNED (TREE_TYPE (TREE_OPERAND (arg0, 0)))) | |
4752 | { | |
4753 | int prec = TYPE_PRECISION (TREE_TYPE (TREE_OPERAND (arg0, 0))); | |
906c4e36 RK |
4754 | if (prec < BITS_PER_WORD && prec < HOST_BITS_PER_WIDE_INT |
4755 | && (~TREE_INT_CST_LOW (arg1) | |
4756 | & (((HOST_WIDE_INT) 1 << prec) - 1)) == 0) | |
6d716ca8 RS |
4757 | return build1 (NOP_EXPR, type, TREE_OPERAND (arg0, 0)); |
4758 | } | |
4759 | goto associate; | |
4760 | ||
4761 | case BIT_ANDTC_EXPR: | |
4762 | if (integer_all_onesp (arg0)) | |
4763 | return non_lvalue (convert (type, arg1)); | |
4764 | if (integer_zerop (arg0)) | |
4765 | return omit_one_operand (type, arg0, arg1); | |
4766 | if (TREE_CODE (arg1) == INTEGER_CST) | |
4767 | { | |
4768 | arg1 = fold (build1 (BIT_NOT_EXPR, type, arg1)); | |
4769 | code = BIT_AND_EXPR; | |
4770 | goto bit_and; | |
4771 | } | |
4772 | goto binary; | |
4773 | ||
e9aaa5a5 RK |
4774 | case RDIV_EXPR: |
4775 | /* In most cases, do nothing with a divide by zero. */ | |
4776 | #if !defined (REAL_IS_NOT_DOUBLE) || defined (REAL_ARITHMETIC) | |
4777 | #ifndef REAL_INFINITY | |
4778 | if (TREE_CODE (arg1) == REAL_CST && real_zerop (arg1)) | |
4779 | return t; | |
4780 | #endif | |
4781 | #endif /* not REAL_IS_NOT_DOUBLE, or REAL_ARITHMETIC */ | |
4782 | ||
4783 | /* In IEEE floating point, x/1 is not equivalent to x for snans. | |
4784 | However, ANSI says we can drop signals, so we can do this anyway. */ | |
4785 | if (real_onep (arg1)) | |
4786 | return non_lvalue (convert (type, arg0)); | |
4787 | ||
4788 | /* If ARG1 is a constant, we can convert this to a multiply by the | |
4789 | reciprocal. This does not have the same rounding properties, | |
4790 | so only do this if -ffast-math. We can actually always safely | |
4791 | do it if ARG1 is a power of two, but it's hard to tell if it is | |
4792 | or not in a portable manner. */ | |
39647dcb RK |
4793 | if (TREE_CODE (arg1) == REAL_CST) |
4794 | { | |
4795 | if (flag_fast_math | |
4796 | && 0 != (tem = const_binop (code, build_real (type, dconst1), | |
4797 | arg1, 0))) | |
4798 | return fold (build (MULT_EXPR, type, arg0, tem)); | |
4799 | /* Find the reciprocal if optimizing and the result is exact. */ | |
4800 | else if (optimize) | |
4801 | { | |
4802 | REAL_VALUE_TYPE r; | |
4803 | r = TREE_REAL_CST (arg1); | |
4804 | if (exact_real_inverse (TYPE_MODE(TREE_TYPE(arg0)), &r)) | |
4805 | { | |
4806 | tem = build_real (type, r); | |
4807 | return fold (build (MULT_EXPR, type, arg0, tem)); | |
4808 | } | |
4809 | } | |
4810 | } | |
e9aaa5a5 RK |
4811 | goto binary; |
4812 | ||
6d716ca8 RS |
4813 | case TRUNC_DIV_EXPR: |
4814 | case ROUND_DIV_EXPR: | |
4815 | case FLOOR_DIV_EXPR: | |
4816 | case CEIL_DIV_EXPR: | |
4817 | case EXACT_DIV_EXPR: | |
6d716ca8 RS |
4818 | if (integer_onep (arg1)) |
4819 | return non_lvalue (convert (type, arg0)); | |
4820 | if (integer_zerop (arg1)) | |
4821 | return t; | |
3b998c11 | 4822 | |
39dfb55a JL |
4823 | /* If arg0 is a multiple of arg1, then rewrite to the fastest div |
4824 | operation, EXACT_DIV_EXPR. | |
4825 | ||
91585c63 TM |
4826 | Note that only CEIL_DIV_EXPR and FLOOR_DIV_EXPR are rewritten now. |
4827 | At one time others generated faster code, it's not clear if they do | |
4828 | after the last round to changes to the DIV code in expmed.c. */ | |
4829 | if ((code == CEIL_DIV_EXPR || code == FLOOR_DIV_EXPR) | |
39dfb55a JL |
4830 | && multiple_of_p (type, arg0, arg1)) |
4831 | return fold (build (EXACT_DIV_EXPR, type, arg0, arg1)); | |
4832 | ||
37bdb7e3 | 4833 | /* If we have ((a / C1) / C2) where both division are the same type, try |
e9aaa5a5 RK |
4834 | to simplify. First see if C1 * C2 overflows or not. */ |
4835 | if (TREE_CODE (arg0) == code && TREE_CODE (arg1) == INTEGER_CST | |
4836 | && TREE_CODE (TREE_OPERAND (arg0, 1)) == INTEGER_CST) | |
4837 | { | |
37bdb7e3 | 4838 | tree new_divisor; |
e9aaa5a5 | 4839 | |
37bdb7e3 TG |
4840 | new_divisor = const_binop (MULT_EXPR, TREE_OPERAND (arg0, 1), arg1, 0); |
4841 | tem = const_binop (FLOOR_DIV_EXPR, new_divisor, arg1, 0); | |
3122945e | 4842 | |
37bdb7e3 TG |
4843 | if (TREE_INT_CST_LOW (TREE_OPERAND (arg0, 1)) == TREE_INT_CST_LOW (tem) |
4844 | && TREE_INT_CST_HIGH (TREE_OPERAND (arg0, 1)) == TREE_INT_CST_HIGH (tem)) | |
e9aaa5a5 | 4845 | { |
37bdb7e3 TG |
4846 | /* If no overflow, divide by C1*C2. */ |
4847 | return fold (build (code, type, TREE_OPERAND (arg0, 0), new_divisor)); | |
e9aaa5a5 | 4848 | } |
e9aaa5a5 RK |
4849 | } |
4850 | ||
6a96fcb4 RK |
4851 | /* Look for ((a * C1) / C3) or (((a * C1) + C2) / C3), |
4852 | where C1 % C3 == 0 or C3 % C1 == 0. We can simplify these | |
4853 | expressions, which often appear in the offsets or sizes of | |
4854 | objects with a varying size. Only deal with positive divisors | |
aae67841 | 4855 | and multiplicands. If C2 is negative, we must have C2 % C3 == 0. |
6a96fcb4 RK |
4856 | |
4857 | Look for NOPs and SAVE_EXPRs inside. */ | |
4858 | ||
3b998c11 | 4859 | if (TREE_CODE (arg1) == INTEGER_CST |
d0cb4c65 | 4860 | && tree_int_cst_sgn (arg1) >= 0) |
3b998c11 | 4861 | { |
6a96fcb4 RK |
4862 | int have_save_expr = 0; |
4863 | tree c2 = integer_zero_node; | |
4864 | tree xarg0 = arg0; | |
3b998c11 | 4865 | |
d011fbf9 | 4866 | if (TREE_CODE (xarg0) == SAVE_EXPR && SAVE_EXPR_RTL (xarg0) == 0) |
6a96fcb4 | 4867 | have_save_expr = 1, xarg0 = TREE_OPERAND (xarg0, 0); |
3b998c11 | 4868 | |
6a96fcb4 RK |
4869 | STRIP_NOPS (xarg0); |
4870 | ||
750e8348 TM |
4871 | /* Look inside the dividend and simplify using EXACT_DIV_EXPR |
4872 | if possible. */ | |
4873 | if (TREE_CODE (xarg0) == MULT_EXPR | |
4874 | && multiple_of_p (type, TREE_OPERAND (xarg0, 0), arg1)) | |
4875 | { | |
4876 | tree t; | |
4877 | ||
4878 | t = fold (build (MULT_EXPR, type, | |
4879 | fold (build (EXACT_DIV_EXPR, type, | |
4880 | TREE_OPERAND (xarg0, 0), arg1)), | |
4881 | TREE_OPERAND (xarg0, 1))); | |
4882 | if (have_save_expr) | |
4883 | t = save_expr (t); | |
4884 | return t; | |
4885 | ||
4886 | } | |
4887 | ||
4888 | if (TREE_CODE (xarg0) == MULT_EXPR | |
4889 | && multiple_of_p (type, TREE_OPERAND (xarg0, 1), arg1)) | |
4890 | { | |
4891 | tree t; | |
4892 | ||
4893 | t = fold (build (MULT_EXPR, type, | |
4894 | fold (build (EXACT_DIV_EXPR, type, | |
4895 | TREE_OPERAND (xarg0, 1), arg1)), | |
4896 | TREE_OPERAND (xarg0, 0))); | |
4897 | if (have_save_expr) | |
4898 | t = save_expr (t); | |
4899 | return t; | |
4900 | } | |
4901 | ||
6a96fcb4 RK |
4902 | if (TREE_CODE (xarg0) == PLUS_EXPR |
4903 | && TREE_CODE (TREE_OPERAND (xarg0, 1)) == INTEGER_CST) | |
4904 | c2 = TREE_OPERAND (xarg0, 1), xarg0 = TREE_OPERAND (xarg0, 0); | |
4905 | else if (TREE_CODE (xarg0) == MINUS_EXPR | |
aae67841 RK |
4906 | && TREE_CODE (TREE_OPERAND (xarg0, 1)) == INTEGER_CST |
4907 | /* If we are doing this computation unsigned, the negate | |
4908 | is incorrect. */ | |
4909 | && ! TREE_UNSIGNED (type)) | |
6a96fcb4 RK |
4910 | { |
4911 | c2 = fold (build1 (NEGATE_EXPR, type, TREE_OPERAND (xarg0, 1))); | |
4912 | xarg0 = TREE_OPERAND (xarg0, 0); | |
4913 | } | |
4914 | ||
d011fbf9 | 4915 | if (TREE_CODE (xarg0) == SAVE_EXPR && SAVE_EXPR_RTL (xarg0) == 0) |
6a96fcb4 RK |
4916 | have_save_expr = 1, xarg0 = TREE_OPERAND (xarg0, 0); |
4917 | ||
4918 | STRIP_NOPS (xarg0); | |
4919 | ||
4920 | if (TREE_CODE (xarg0) == MULT_EXPR | |
4921 | && TREE_CODE (TREE_OPERAND (xarg0, 1)) == INTEGER_CST | |
d0cb4c65 | 4922 | && tree_int_cst_sgn (TREE_OPERAND (xarg0, 1)) >= 0 |
6a96fcb4 RK |
4923 | && (integer_zerop (const_binop (TRUNC_MOD_EXPR, |
4924 | TREE_OPERAND (xarg0, 1), arg1, 1)) | |
4925 | || integer_zerop (const_binop (TRUNC_MOD_EXPR, arg1, | |
aae67841 | 4926 | TREE_OPERAND (xarg0, 1), 1))) |
d0cb4c65 | 4927 | && (tree_int_cst_sgn (c2) >= 0 |
aae67841 RK |
4928 | || integer_zerop (const_binop (TRUNC_MOD_EXPR, c2, |
4929 | arg1, 1)))) | |
6a96fcb4 RK |
4930 | { |
4931 | tree outer_div = integer_one_node; | |
4932 | tree c1 = TREE_OPERAND (xarg0, 1); | |
4933 | tree c3 = arg1; | |
4934 | ||
4935 | /* If C3 > C1, set them equal and do a divide by | |
4936 | C3/C1 at the end of the operation. */ | |
4937 | if (tree_int_cst_lt (c1, c3)) | |
4938 | outer_div = const_binop (code, c3, c1, 0), c3 = c1; | |
4939 | ||
4940 | /* The result is A * (C1/C3) + (C2/C3). */ | |
4941 | t = fold (build (PLUS_EXPR, type, | |
4942 | fold (build (MULT_EXPR, type, | |
4943 | TREE_OPERAND (xarg0, 0), | |
4944 | const_binop (code, c1, c3, 1))), | |
4945 | const_binop (code, c2, c3, 1))); | |
4946 | ||
4947 | if (! integer_onep (outer_div)) | |
d0cb4c65 | 4948 | t = fold (build (code, type, t, convert (type, outer_div))); |
6a96fcb4 RK |
4949 | |
4950 | if (have_save_expr) | |
4951 | t = save_expr (t); | |
4952 | ||
4953 | return t; | |
4954 | } | |
3b998c11 RK |
4955 | } |
4956 | ||
6d716ca8 RS |
4957 | goto binary; |
4958 | ||
4959 | case CEIL_MOD_EXPR: | |
4960 | case FLOOR_MOD_EXPR: | |
4961 | case ROUND_MOD_EXPR: | |
4962 | case TRUNC_MOD_EXPR: | |
4963 | if (integer_onep (arg1)) | |
4964 | return omit_one_operand (type, integer_zero_node, arg0); | |
4965 | if (integer_zerop (arg1)) | |
4966 | return t; | |
6a96fcb4 RK |
4967 | |
4968 | /* Look for ((a * C1) % C3) or (((a * C1) + C2) % C3), | |
4969 | where C1 % C3 == 0. Handle similarly to the division case, | |
4970 | but don't bother with SAVE_EXPRs. */ | |
4971 | ||
4972 | if (TREE_CODE (arg1) == INTEGER_CST | |
4973 | && ! integer_zerop (arg1)) | |
4974 | { | |
4975 | tree c2 = integer_zero_node; | |
4976 | tree xarg0 = arg0; | |
4977 | ||
4978 | if (TREE_CODE (xarg0) == PLUS_EXPR | |
4979 | && TREE_CODE (TREE_OPERAND (xarg0, 1)) == INTEGER_CST) | |
4980 | c2 = TREE_OPERAND (xarg0, 1), xarg0 = TREE_OPERAND (xarg0, 0); | |
4981 | else if (TREE_CODE (xarg0) == MINUS_EXPR | |
aae67841 RK |
4982 | && TREE_CODE (TREE_OPERAND (xarg0, 1)) == INTEGER_CST |
4983 | && ! TREE_UNSIGNED (type)) | |
6a96fcb4 RK |
4984 | { |
4985 | c2 = fold (build1 (NEGATE_EXPR, type, TREE_OPERAND (xarg0, 1))); | |
4986 | xarg0 = TREE_OPERAND (xarg0, 0); | |
4987 | } | |
4988 | ||
4989 | STRIP_NOPS (xarg0); | |
4990 | ||
4991 | if (TREE_CODE (xarg0) == MULT_EXPR | |
4992 | && TREE_CODE (TREE_OPERAND (xarg0, 1)) == INTEGER_CST | |
4993 | && integer_zerop (const_binop (TRUNC_MOD_EXPR, | |
4994 | TREE_OPERAND (xarg0, 1), | |
aae67841 | 4995 | arg1, 1)) |
d0cb4c65 | 4996 | && tree_int_cst_sgn (c2) >= 0) |
6a96fcb4 RK |
4997 | /* The result is (C2%C3). */ |
4998 | return omit_one_operand (type, const_binop (code, c2, arg1, 1), | |
4999 | TREE_OPERAND (xarg0, 0)); | |
5000 | } | |
5001 | ||
6d716ca8 RS |
5002 | goto binary; |
5003 | ||
5004 | case LSHIFT_EXPR: | |
5005 | case RSHIFT_EXPR: | |
5006 | case LROTATE_EXPR: | |
5007 | case RROTATE_EXPR: | |
5008 | if (integer_zerop (arg1)) | |
5009 | return non_lvalue (convert (type, arg0)); | |
5010 | /* Since negative shift count is not well-defined, | |
5011 | don't try to compute it in the compiler. */ | |
4d39710e | 5012 | if (TREE_CODE (arg1) == INTEGER_CST && tree_int_cst_sgn (arg1) < 0) |
6d716ca8 | 5013 | return t; |
4d39710e RK |
5014 | /* Rewrite an LROTATE_EXPR by a constant into an |
5015 | RROTATE_EXPR by a new constant. */ | |
5016 | if (code == LROTATE_EXPR && TREE_CODE (arg1) == INTEGER_CST) | |
5017 | { | |
5018 | TREE_SET_CODE (t, RROTATE_EXPR); | |
5019 | code = RROTATE_EXPR; | |
5020 | TREE_OPERAND (t, 1) = arg1 | |
5021 | = const_binop | |
5022 | (MINUS_EXPR, | |
5023 | convert (TREE_TYPE (arg1), | |
5024 | build_int_2 (GET_MODE_BITSIZE (TYPE_MODE (type)), 0)), | |
5025 | arg1, 0); | |
5026 | if (tree_int_cst_sgn (arg1) < 0) | |
5027 | return t; | |
5028 | } | |
5029 | ||
5030 | /* If we have a rotate of a bit operation with the rotate count and | |
5031 | the second operand of the bit operation both constant, | |
5032 | permute the two operations. */ | |
5033 | if (code == RROTATE_EXPR && TREE_CODE (arg1) == INTEGER_CST | |
5034 | && (TREE_CODE (arg0) == BIT_AND_EXPR | |
5035 | || TREE_CODE (arg0) == BIT_ANDTC_EXPR | |
5036 | || TREE_CODE (arg0) == BIT_IOR_EXPR | |
5037 | || TREE_CODE (arg0) == BIT_XOR_EXPR) | |
5038 | && TREE_CODE (TREE_OPERAND (arg0, 1)) == INTEGER_CST) | |
5039 | return fold (build (TREE_CODE (arg0), type, | |
5040 | fold (build (code, type, | |
5041 | TREE_OPERAND (arg0, 0), arg1)), | |
5042 | fold (build (code, type, | |
5043 | TREE_OPERAND (arg0, 1), arg1)))); | |
5044 | ||
5045 | /* Two consecutive rotates adding up to the width of the mode can | |
5046 | be ignored. */ | |
5047 | if (code == RROTATE_EXPR && TREE_CODE (arg1) == INTEGER_CST | |
5048 | && TREE_CODE (arg0) == RROTATE_EXPR | |
5049 | && TREE_CODE (TREE_OPERAND (arg0, 1)) == INTEGER_CST | |
5050 | && TREE_INT_CST_HIGH (arg1) == 0 | |
5051 | && TREE_INT_CST_HIGH (TREE_OPERAND (arg0, 1)) == 0 | |
5052 | && ((TREE_INT_CST_LOW (arg1) | |
5053 | + TREE_INT_CST_LOW (TREE_OPERAND (arg0, 1))) | |
5054 | == GET_MODE_BITSIZE (TYPE_MODE (type)))) | |
5055 | return TREE_OPERAND (arg0, 0); | |
5056 | ||
6d716ca8 RS |
5057 | goto binary; |
5058 | ||
5059 | case MIN_EXPR: | |
5060 | if (operand_equal_p (arg0, arg1, 0)) | |
5061 | return arg0; | |
7178e3af | 5062 | if (INTEGRAL_TYPE_P (type) |
6d716ca8 RS |
5063 | && operand_equal_p (arg1, TYPE_MIN_VALUE (type), 1)) |
5064 | return omit_one_operand (type, arg1, arg0); | |
5065 | goto associate; | |
5066 | ||
5067 | case MAX_EXPR: | |
5068 | if (operand_equal_p (arg0, arg1, 0)) | |
5069 | return arg0; | |
7178e3af | 5070 | if (INTEGRAL_TYPE_P (type) |
e1ee5cdc | 5071 | && TYPE_MAX_VALUE (type) |
6d716ca8 RS |
5072 | && operand_equal_p (arg1, TYPE_MAX_VALUE (type), 1)) |
5073 | return omit_one_operand (type, arg1, arg0); | |
5074 | goto associate; | |
5075 | ||
5076 | case TRUTH_NOT_EXPR: | |
5077 | /* Note that the operand of this must be an int | |
5078 | and its values must be 0 or 1. | |
5079 | ("true" is a fixed value perhaps depending on the language, | |
5080 | but we don't handle values other than 1 correctly yet.) */ | |
1180eb10 JM |
5081 | tem = invert_truthvalue (arg0); |
5082 | /* Avoid infinite recursion. */ | |
5083 | if (TREE_CODE (tem) == TRUTH_NOT_EXPR) | |
5084 | return t; | |
5085 | return convert (type, tem); | |
6d716ca8 RS |
5086 | |
5087 | case TRUTH_ANDIF_EXPR: | |
5088 | /* Note that the operands of this must be ints | |
5089 | and their values must be 0 or 1. | |
5090 | ("true" is a fixed value perhaps depending on the language.) */ | |
5091 | /* If first arg is constant zero, return it. */ | |
772447c5 | 5092 | if (integer_zerop (arg0)) |
6d716ca8 RS |
5093 | return arg0; |
5094 | case TRUTH_AND_EXPR: | |
5095 | /* If either arg is constant true, drop it. */ | |
5096 | if (TREE_CODE (arg0) == INTEGER_CST && ! integer_zerop (arg0)) | |
5097 | return non_lvalue (arg1); | |
5098 | if (TREE_CODE (arg1) == INTEGER_CST && ! integer_zerop (arg1)) | |
5099 | return non_lvalue (arg0); | |
772447c5 RK |
5100 | /* If second arg is constant zero, result is zero, but first arg |
5101 | must be evaluated. */ | |
5102 | if (integer_zerop (arg1)) | |
5103 | return omit_one_operand (type, arg1, arg0); | |
80906567 RK |
5104 | /* Likewise for first arg, but note that only the TRUTH_AND_EXPR |
5105 | case will be handled here. */ | |
5106 | if (integer_zerop (arg0)) | |
5107 | return omit_one_operand (type, arg0, arg1); | |
6d716ca8 RS |
5108 | |
5109 | truth_andor: | |
e9b5e15f RK |
5110 | /* We only do these simplifications if we are optimizing. */ |
5111 | if (!optimize) | |
5112 | return t; | |
5113 | ||
5114 | /* Check for things like (A || B) && (A || C). We can convert this | |
5115 | to A || (B && C). Note that either operator can be any of the four | |
5116 | truth and/or operations and the transformation will still be | |
5117 | valid. Also note that we only care about order for the | |
96f06cb6 RK |
5118 | ANDIF and ORIF operators. If B contains side effects, this |
5119 | might change the truth-value of A. */ | |
e9b5e15f RK |
5120 | if (TREE_CODE (arg0) == TREE_CODE (arg1) |
5121 | && (TREE_CODE (arg0) == TRUTH_ANDIF_EXPR | |
5122 | || TREE_CODE (arg0) == TRUTH_ORIF_EXPR | |
5123 | || TREE_CODE (arg0) == TRUTH_AND_EXPR | |
96f06cb6 RK |
5124 | || TREE_CODE (arg0) == TRUTH_OR_EXPR) |
5125 | && ! TREE_SIDE_EFFECTS (TREE_OPERAND (arg0, 1))) | |
e9b5e15f RK |
5126 | { |
5127 | tree a00 = TREE_OPERAND (arg0, 0); | |
5128 | tree a01 = TREE_OPERAND (arg0, 1); | |
5129 | tree a10 = TREE_OPERAND (arg1, 0); | |
5130 | tree a11 = TREE_OPERAND (arg1, 1); | |
5131 | int commutative = ((TREE_CODE (arg0) == TRUTH_OR_EXPR | |
5132 | || TREE_CODE (arg0) == TRUTH_AND_EXPR) | |
5133 | && (code == TRUTH_AND_EXPR | |
5134 | || code == TRUTH_OR_EXPR)); | |
5135 | ||
5136 | if (operand_equal_p (a00, a10, 0)) | |
5137 | return fold (build (TREE_CODE (arg0), type, a00, | |
5138 | fold (build (code, type, a01, a11)))); | |
5139 | else if (commutative && operand_equal_p (a00, a11, 0)) | |
5140 | return fold (build (TREE_CODE (arg0), type, a00, | |
5141 | fold (build (code, type, a01, a10)))); | |
5142 | else if (commutative && operand_equal_p (a01, a10, 0)) | |
5143 | return fold (build (TREE_CODE (arg0), type, a01, | |
5144 | fold (build (code, type, a00, a11)))); | |
5145 | ||
5146 | /* This case if tricky because we must either have commutative | |
5147 | operators or else A10 must not have side-effects. */ | |
5148 | ||
5149 | else if ((commutative || ! TREE_SIDE_EFFECTS (a10)) | |
5150 | && operand_equal_p (a01, a11, 0)) | |
5151 | return fold (build (TREE_CODE (arg0), type, | |
5152 | fold (build (code, type, a00, a10)), | |
5153 | a01)); | |
5154 | } | |
5155 | ||
ebde8a27 RK |
5156 | /* See if we can build a range comparison. */ |
5157 | if (0 != (tem = fold_range_test (t))) | |
5158 | return tem; | |
5159 | ||
6d716ca8 RS |
5160 | /* Check for the possibility of merging component references. If our |
5161 | lhs is another similar operation, try to merge its rhs with our | |
5162 | rhs. Then try to merge our lhs and rhs. */ | |
e9b5e15f RK |
5163 | if (TREE_CODE (arg0) == code |
5164 | && 0 != (tem = fold_truthop (code, type, | |
5165 | TREE_OPERAND (arg0, 1), arg1))) | |
5166 | return fold (build (code, type, TREE_OPERAND (arg0, 0), tem)); | |
6d716ca8 | 5167 | |
e9b5e15f RK |
5168 | if ((tem = fold_truthop (code, type, arg0, arg1)) != 0) |
5169 | return tem; | |
61f275ff | 5170 | |
6d716ca8 RS |
5171 | return t; |
5172 | ||
5173 | case TRUTH_ORIF_EXPR: | |
5174 | /* Note that the operands of this must be ints | |
5175 | and their values must be 0 or true. | |
5176 | ("true" is a fixed value perhaps depending on the language.) */ | |
5177 | /* If first arg is constant true, return it. */ | |
5178 | if (TREE_CODE (arg0) == INTEGER_CST && ! integer_zerop (arg0)) | |
5179 | return arg0; | |
5180 | case TRUTH_OR_EXPR: | |
5181 | /* If either arg is constant zero, drop it. */ | |
5182 | if (TREE_CODE (arg0) == INTEGER_CST && integer_zerop (arg0)) | |
5183 | return non_lvalue (arg1); | |
5184 | if (TREE_CODE (arg1) == INTEGER_CST && integer_zerop (arg1)) | |
5185 | return non_lvalue (arg0); | |
772447c5 RK |
5186 | /* If second arg is constant true, result is true, but we must |
5187 | evaluate first arg. */ | |
5188 | if (TREE_CODE (arg1) == INTEGER_CST && ! integer_zerop (arg1)) | |
5189 | return omit_one_operand (type, arg1, arg0); | |
80906567 RK |
5190 | /* Likewise for first arg, but note this only occurs here for |
5191 | TRUTH_OR_EXPR. */ | |
5192 | if (TREE_CODE (arg0) == INTEGER_CST && ! integer_zerop (arg0)) | |
5193 | return omit_one_operand (type, arg0, arg1); | |
6d716ca8 RS |
5194 | goto truth_andor; |
5195 | ||
772447c5 RK |
5196 | case TRUTH_XOR_EXPR: |
5197 | /* If either arg is constant zero, drop it. */ | |
5198 | if (integer_zerop (arg0)) | |
5199 | return non_lvalue (arg1); | |
5200 | if (integer_zerop (arg1)) | |
5201 | return non_lvalue (arg0); | |
5202 | /* If either arg is constant true, this is a logical inversion. */ | |
5203 | if (integer_onep (arg0)) | |
5204 | return non_lvalue (invert_truthvalue (arg1)); | |
5205 | if (integer_onep (arg1)) | |
5206 | return non_lvalue (invert_truthvalue (arg0)); | |
62d8b51e | 5207 | return t; |
772447c5 | 5208 | |
6d716ca8 RS |
5209 | case EQ_EXPR: |
5210 | case NE_EXPR: | |
5211 | case LT_EXPR: | |
5212 | case GT_EXPR: | |
5213 | case LE_EXPR: | |
5214 | case GE_EXPR: | |
5215 | /* If one arg is a constant integer, put it last. */ | |
5216 | if (TREE_CODE (arg0) == INTEGER_CST | |
5217 | && TREE_CODE (arg1) != INTEGER_CST) | |
5218 | { | |
5219 | TREE_OPERAND (t, 0) = arg1; | |
5220 | TREE_OPERAND (t, 1) = arg0; | |
5221 | arg0 = TREE_OPERAND (t, 0); | |
5222 | arg1 = TREE_OPERAND (t, 1); | |
c05a9b68 | 5223 | code = swap_tree_comparison (code); |
6d716ca8 RS |
5224 | TREE_SET_CODE (t, code); |
5225 | } | |
5226 | ||
5227 | /* Convert foo++ == CONST into ++foo == CONST + INCR. | |
5228 | First, see if one arg is constant; find the constant arg | |
5229 | and the other one. */ | |
5230 | { | |
4e86caed | 5231 | tree constop = 0, varop = NULL_TREE; |
cd7ece66 | 5232 | int constopnum = -1; |
6d716ca8 RS |
5233 | |
5234 | if (TREE_CONSTANT (arg1)) | |
cd7ece66 | 5235 | constopnum = 1, constop = arg1, varop = arg0; |
6d716ca8 | 5236 | if (TREE_CONSTANT (arg0)) |
cd7ece66 | 5237 | constopnum = 0, constop = arg0, varop = arg1; |
6d716ca8 RS |
5238 | |
5239 | if (constop && TREE_CODE (varop) == POSTINCREMENT_EXPR) | |
5240 | { | |
6d716ca8 RS |
5241 | /* This optimization is invalid for ordered comparisons |
5242 | if CONST+INCR overflows or if foo+incr might overflow. | |
c05a9b68 | 5243 | This optimization is invalid for floating point due to rounding. |
6d716ca8 | 5244 | For pointer types we assume overflow doesn't happen. */ |
e5e809f4 | 5245 | if (POINTER_TYPE_P (TREE_TYPE (varop)) |
7178e3af | 5246 | || (! FLOAT_TYPE_P (TREE_TYPE (varop)) |
c05a9b68 | 5247 | && (code == EQ_EXPR || code == NE_EXPR))) |
6d716ca8 | 5248 | { |
c05a9b68 RS |
5249 | tree newconst |
5250 | = fold (build (PLUS_EXPR, TREE_TYPE (varop), | |
5251 | constop, TREE_OPERAND (varop, 1))); | |
5252 | TREE_SET_CODE (varop, PREINCREMENT_EXPR); | |
cd7ece66 | 5253 | |
30eca391 RK |
5254 | /* If VAROP is a reference to a bitfield, we must mask |
5255 | the constant by the width of the field. */ | |
5256 | if (TREE_CODE (TREE_OPERAND (varop, 0)) == COMPONENT_REF | |
5257 | && DECL_BIT_FIELD(TREE_OPERAND | |
5258 | (TREE_OPERAND (varop, 0), 1))) | |
5259 | { | |
5260 | int size | |
5261 | = TREE_INT_CST_LOW (DECL_SIZE | |
5262 | (TREE_OPERAND | |
5263 | (TREE_OPERAND (varop, 0), 1))); | |
df0e526f AS |
5264 | tree mask, unsigned_type; |
5265 | int precision; | |
5266 | tree folded_compare; | |
5267 | ||
5268 | /* First check whether the comparison would come out | |
5269 | always the same. If we don't do that we would | |
5270 | change the meaning with the masking. */ | |
5271 | if (constopnum == 0) | |
5272 | folded_compare = fold (build (code, type, constop, | |
5273 | TREE_OPERAND (varop, 0))); | |
5274 | else | |
5275 | folded_compare = fold (build (code, type, | |
5276 | TREE_OPERAND (varop, 0), | |
5277 | constop)); | |
5278 | if (integer_zerop (folded_compare) | |
5279 | || integer_onep (folded_compare)) | |
5280 | return omit_one_operand (type, folded_compare, varop); | |
5281 | ||
5282 | unsigned_type = type_for_size (size, 1); | |
5283 | precision = TYPE_PRECISION (unsigned_type); | |
5284 | mask = build_int_2 (~0, ~0); | |
5285 | TREE_TYPE (mask) = unsigned_type; | |
5286 | force_fit_type (mask, 0); | |
5287 | mask = const_binop (RSHIFT_EXPR, mask, | |
5288 | size_int (precision - size), 0); | |
30eca391 RK |
5289 | newconst = fold (build (BIT_AND_EXPR, |
5290 | TREE_TYPE (varop), newconst, | |
5291 | convert (TREE_TYPE (varop), | |
df0e526f | 5292 | mask))); |
30eca391 RK |
5293 | } |
5294 | ||
5295 | ||
cd7ece66 RK |
5296 | t = build (code, type, TREE_OPERAND (t, 0), |
5297 | TREE_OPERAND (t, 1)); | |
5298 | TREE_OPERAND (t, constopnum) = newconst; | |
c05a9b68 | 5299 | return t; |
6d716ca8 RS |
5300 | } |
5301 | } | |
5302 | else if (constop && TREE_CODE (varop) == POSTDECREMENT_EXPR) | |
5303 | { | |
e5e809f4 | 5304 | if (POINTER_TYPE_P (TREE_TYPE (varop)) |
7178e3af | 5305 | || (! FLOAT_TYPE_P (TREE_TYPE (varop)) |
c05a9b68 | 5306 | && (code == EQ_EXPR || code == NE_EXPR))) |
6d716ca8 | 5307 | { |
c05a9b68 RS |
5308 | tree newconst |
5309 | = fold (build (MINUS_EXPR, TREE_TYPE (varop), | |
5310 | constop, TREE_OPERAND (varop, 1))); | |
5311 | TREE_SET_CODE (varop, PREDECREMENT_EXPR); | |
30eca391 RK |
5312 | |
5313 | if (TREE_CODE (TREE_OPERAND (varop, 0)) == COMPONENT_REF | |
5314 | && DECL_BIT_FIELD(TREE_OPERAND | |
5315 | (TREE_OPERAND (varop, 0), 1))) | |
5316 | { | |
5317 | int size | |
5318 | = TREE_INT_CST_LOW (DECL_SIZE | |
5319 | (TREE_OPERAND | |
5320 | (TREE_OPERAND (varop, 0), 1))); | |
df0e526f AS |
5321 | tree mask, unsigned_type; |
5322 | int precision; | |
5323 | tree folded_compare; | |
5324 | ||
5325 | if (constopnum == 0) | |
5326 | folded_compare = fold (build (code, type, constop, | |
5327 | TREE_OPERAND (varop, 0))); | |
5328 | else | |
5329 | folded_compare = fold (build (code, type, | |
5330 | TREE_OPERAND (varop, 0), | |
5331 | constop)); | |
5332 | if (integer_zerop (folded_compare) | |
5333 | || integer_onep (folded_compare)) | |
5334 | return omit_one_operand (type, folded_compare, varop); | |
5335 | ||
5336 | unsigned_type = type_for_size (size, 1); | |
5337 | precision = TYPE_PRECISION (unsigned_type); | |
5338 | mask = build_int_2 (~0, ~0); | |
5339 | TREE_TYPE (mask) = TREE_TYPE (varop); | |
5340 | force_fit_type (mask, 0); | |
5341 | mask = const_binop (RSHIFT_EXPR, mask, | |
5342 | size_int (precision - size), 0); | |
30eca391 RK |
5343 | newconst = fold (build (BIT_AND_EXPR, |
5344 | TREE_TYPE (varop), newconst, | |
5345 | convert (TREE_TYPE (varop), | |
df0e526f | 5346 | mask))); |
30eca391 RK |
5347 | } |
5348 | ||
5349 | ||
cd7ece66 RK |
5350 | t = build (code, type, TREE_OPERAND (t, 0), |
5351 | TREE_OPERAND (t, 1)); | |
5352 | TREE_OPERAND (t, constopnum) = newconst; | |
c05a9b68 | 5353 | return t; |
6d716ca8 RS |
5354 | } |
5355 | } | |
5356 | } | |
5357 | ||
5358 | /* Change X >= CST to X > (CST - 1) if CST is positive. */ | |
5359 | if (TREE_CODE (arg1) == INTEGER_CST | |
5360 | && TREE_CODE (arg0) != INTEGER_CST | |
d0cb4c65 | 5361 | && tree_int_cst_sgn (arg1) > 0) |
6d716ca8 RS |
5362 | { |
5363 | switch (TREE_CODE (t)) | |
5364 | { | |
5365 | case GE_EXPR: | |
5366 | code = GT_EXPR; | |
91d33e36 | 5367 | arg1 = const_binop (MINUS_EXPR, arg1, integer_one_node, 0); |
cd7ece66 | 5368 | t = build (code, type, TREE_OPERAND (t, 0), arg1); |
6d716ca8 RS |
5369 | break; |
5370 | ||
5371 | case LT_EXPR: | |
5372 | code = LE_EXPR; | |
91d33e36 | 5373 | arg1 = const_binop (MINUS_EXPR, arg1, integer_one_node, 0); |
cd7ece66 RK |
5374 | t = build (code, type, TREE_OPERAND (t, 0), arg1); |
5375 | break; | |
e9a25f70 JL |
5376 | |
5377 | default: | |
5378 | break; | |
6d716ca8 RS |
5379 | } |
5380 | } | |
5381 | ||
6d716ca8 RS |
5382 | /* If this is an EQ or NE comparison with zero and ARG0 is |
5383 | (1 << foo) & bar, convert it to (bar >> foo) & 1. Both require | |
5384 | two operations, but the latter can be done in one less insn | |
e9a25f70 | 5385 | on machines that have only two-operand insns or on which a |
6d716ca8 RS |
5386 | constant cannot be the first operand. */ |
5387 | if (integer_zerop (arg1) && (code == EQ_EXPR || code == NE_EXPR) | |
5388 | && TREE_CODE (arg0) == BIT_AND_EXPR) | |
5389 | { | |
5390 | if (TREE_CODE (TREE_OPERAND (arg0, 0)) == LSHIFT_EXPR | |
5391 | && integer_onep (TREE_OPERAND (TREE_OPERAND (arg0, 0), 0))) | |
5392 | return | |
5393 | fold (build (code, type, | |
5394 | build (BIT_AND_EXPR, TREE_TYPE (arg0), | |
5395 | build (RSHIFT_EXPR, | |
5396 | TREE_TYPE (TREE_OPERAND (arg0, 0)), | |
5397 | TREE_OPERAND (arg0, 1), | |
5398 | TREE_OPERAND (TREE_OPERAND (arg0, 0), 1)), | |
5399 | convert (TREE_TYPE (arg0), | |
5400 | integer_one_node)), | |
5401 | arg1)); | |
5402 | else if (TREE_CODE (TREE_OPERAND (arg0, 1)) == LSHIFT_EXPR | |
5403 | && integer_onep (TREE_OPERAND (TREE_OPERAND (arg0, 1), 0))) | |
5404 | return | |
5405 | fold (build (code, type, | |
5406 | build (BIT_AND_EXPR, TREE_TYPE (arg0), | |
5407 | build (RSHIFT_EXPR, | |
5408 | TREE_TYPE (TREE_OPERAND (arg0, 1)), | |
5409 | TREE_OPERAND (arg0, 0), | |
5410 | TREE_OPERAND (TREE_OPERAND (arg0, 1), 1)), | |
5411 | convert (TREE_TYPE (arg0), | |
5412 | integer_one_node)), | |
5413 | arg1)); | |
5414 | } | |
5415 | ||
05a0d5ea | 5416 | /* If this is an NE or EQ comparison of zero against the result of a |
79bf94d3 RK |
5417 | signed MOD operation whose second operand is a power of 2, make |
5418 | the MOD operation unsigned since it is simpler and equivalent. */ | |
05a0d5ea RK |
5419 | if ((code == NE_EXPR || code == EQ_EXPR) |
5420 | && integer_zerop (arg1) | |
5421 | && ! TREE_UNSIGNED (TREE_TYPE (arg0)) | |
5422 | && (TREE_CODE (arg0) == TRUNC_MOD_EXPR | |
5423 | || TREE_CODE (arg0) == CEIL_MOD_EXPR | |
5424 | || TREE_CODE (arg0) == FLOOR_MOD_EXPR | |
79bf94d3 RK |
5425 | || TREE_CODE (arg0) == ROUND_MOD_EXPR) |
5426 | && integer_pow2p (TREE_OPERAND (arg0, 1))) | |
05a0d5ea RK |
5427 | { |
5428 | tree newtype = unsigned_type (TREE_TYPE (arg0)); | |
5429 | tree newmod = build (TREE_CODE (arg0), newtype, | |
5430 | convert (newtype, TREE_OPERAND (arg0, 0)), | |
5431 | convert (newtype, TREE_OPERAND (arg0, 1))); | |
5432 | ||
5433 | return build (code, type, newmod, convert (newtype, arg1)); | |
5434 | } | |
5435 | ||
6d716ca8 RS |
5436 | /* If this is an NE comparison of zero with an AND of one, remove the |
5437 | comparison since the AND will give the correct value. */ | |
5438 | if (code == NE_EXPR && integer_zerop (arg1) | |
5439 | && TREE_CODE (arg0) == BIT_AND_EXPR | |
5440 | && integer_onep (TREE_OPERAND (arg0, 1))) | |
5441 | return convert (type, arg0); | |
5442 | ||
5443 | /* If we have (A & C) == C where C is a power of 2, convert this into | |
5444 | (A & C) != 0. Similarly for NE_EXPR. */ | |
5445 | if ((code == EQ_EXPR || code == NE_EXPR) | |
5446 | && TREE_CODE (arg0) == BIT_AND_EXPR | |
5447 | && integer_pow2p (TREE_OPERAND (arg0, 1)) | |
5448 | && operand_equal_p (TREE_OPERAND (arg0, 1), arg1, 0)) | |
5449 | return build (code == EQ_EXPR ? NE_EXPR : EQ_EXPR, type, | |
5450 | arg0, integer_zero_node); | |
5451 | ||
e92d3048 | 5452 | /* If X is unsigned, convert X < (1 << Y) into X >> Y == 0 |
34b1b41f | 5453 | and similarly for >= into !=. */ |
e92d3048 RK |
5454 | if ((code == LT_EXPR || code == GE_EXPR) |
5455 | && TREE_UNSIGNED (TREE_TYPE (arg0)) | |
5456 | && TREE_CODE (arg1) == LSHIFT_EXPR | |
5457 | && integer_onep (TREE_OPERAND (arg1, 0))) | |
5458 | return build (code == LT_EXPR ? EQ_EXPR : NE_EXPR, type, | |
5459 | build (RSHIFT_EXPR, TREE_TYPE (arg0), arg0, | |
5460 | TREE_OPERAND (arg1, 1)), | |
5461 | convert (TREE_TYPE (arg0), integer_zero_node)); | |
5462 | ||
5463 | else if ((code == LT_EXPR || code == GE_EXPR) | |
5464 | && TREE_UNSIGNED (TREE_TYPE (arg0)) | |
5465 | && (TREE_CODE (arg1) == NOP_EXPR | |
5466 | || TREE_CODE (arg1) == CONVERT_EXPR) | |
5467 | && TREE_CODE (TREE_OPERAND (arg1, 0)) == LSHIFT_EXPR | |
5468 | && integer_onep (TREE_OPERAND (TREE_OPERAND (arg1, 0), 0))) | |
5469 | return | |
5470 | build (code == LT_EXPR ? EQ_EXPR : NE_EXPR, type, | |
5471 | convert (TREE_TYPE (arg0), | |
5472 | build (RSHIFT_EXPR, TREE_TYPE (arg0), arg0, | |
5473 | TREE_OPERAND (TREE_OPERAND (arg1, 0), 1))), | |
5474 | convert (TREE_TYPE (arg0), integer_zero_node)); | |
5475 | ||
c05a9b68 RS |
5476 | /* Simplify comparison of something with itself. (For IEEE |
5477 | floating-point, we can only do some of these simplifications.) */ | |
5478 | if (operand_equal_p (arg0, arg1, 0)) | |
6d716ca8 RS |
5479 | { |
5480 | switch (code) | |
5481 | { | |
5482 | case EQ_EXPR: | |
5483 | case GE_EXPR: | |
5484 | case LE_EXPR: | |
7178e3af | 5485 | if (INTEGRAL_TYPE_P (TREE_TYPE (arg0))) |
f628873f | 5486 | return constant_boolean_node (1, type); |
c05a9b68 RS |
5487 | code = EQ_EXPR; |
5488 | TREE_SET_CODE (t, code); | |
5489 | break; | |
5490 | ||
6d716ca8 | 5491 | case NE_EXPR: |
c05a9b68 | 5492 | /* For NE, we can only do this simplification if integer. */ |
7178e3af | 5493 | if (! INTEGRAL_TYPE_P (TREE_TYPE (arg0))) |
c05a9b68 | 5494 | break; |
0f41302f | 5495 | /* ... fall through ... */ |
6d716ca8 RS |
5496 | case GT_EXPR: |
5497 | case LT_EXPR: | |
f628873f | 5498 | return constant_boolean_node (0, type); |
e9a25f70 JL |
5499 | default: |
5500 | abort (); | |
6d716ca8 RS |
5501 | } |
5502 | } | |
5503 | ||
5504 | /* An unsigned comparison against 0 can be simplified. */ | |
5505 | if (integer_zerop (arg1) | |
7178e3af | 5506 | && (INTEGRAL_TYPE_P (TREE_TYPE (arg1)) |
e5e809f4 | 5507 | || POINTER_TYPE_P (TREE_TYPE (arg1))) |
6d716ca8 RS |
5508 | && TREE_UNSIGNED (TREE_TYPE (arg1))) |
5509 | { | |
5510 | switch (TREE_CODE (t)) | |
5511 | { | |
5512 | case GT_EXPR: | |
c05a9b68 | 5513 | code = NE_EXPR; |
6d716ca8 RS |
5514 | TREE_SET_CODE (t, NE_EXPR); |
5515 | break; | |
5516 | case LE_EXPR: | |
c05a9b68 | 5517 | code = EQ_EXPR; |
6d716ca8 RS |
5518 | TREE_SET_CODE (t, EQ_EXPR); |
5519 | break; | |
5520 | case GE_EXPR: | |
56f8e5e6 RK |
5521 | return omit_one_operand (type, |
5522 | convert (type, integer_one_node), | |
5523 | arg0); | |
6d716ca8 | 5524 | case LT_EXPR: |
56f8e5e6 RK |
5525 | return omit_one_operand (type, |
5526 | convert (type, integer_zero_node), | |
5527 | arg0); | |
e9a25f70 JL |
5528 | default: |
5529 | break; | |
6d716ca8 RS |
5530 | } |
5531 | } | |
5532 | ||
e9a25f70 JL |
5533 | /* An unsigned <= 0x7fffffff can be simplified. */ |
5534 | { | |
5535 | int width = TYPE_PRECISION (TREE_TYPE (arg1)); | |
5536 | if (TREE_CODE (arg1) == INTEGER_CST | |
5537 | && ! TREE_CONSTANT_OVERFLOW (arg1) | |
5538 | && width <= HOST_BITS_PER_WIDE_INT | |
5539 | && TREE_INT_CST_LOW (arg1) == ((HOST_WIDE_INT) 1 << (width - 1)) - 1 | |
5540 | && TREE_INT_CST_HIGH (arg1) == 0 | |
5541 | && (INTEGRAL_TYPE_P (TREE_TYPE (arg1)) | |
e5e809f4 | 5542 | || POINTER_TYPE_P (TREE_TYPE (arg1))) |
e9a25f70 JL |
5543 | && TREE_UNSIGNED (TREE_TYPE (arg1))) |
5544 | { | |
5545 | switch (TREE_CODE (t)) | |
5546 | { | |
5547 | case LE_EXPR: | |
5548 | return fold (build (GE_EXPR, type, | |
5549 | convert (signed_type (TREE_TYPE (arg0)), | |
5550 | arg0), | |
5551 | convert (signed_type (TREE_TYPE (arg1)), | |
5552 | integer_zero_node))); | |
5553 | case GT_EXPR: | |
5554 | return fold (build (LT_EXPR, type, | |
5555 | convert (signed_type (TREE_TYPE (arg0)), | |
5556 | arg0), | |
5557 | convert (signed_type (TREE_TYPE (arg1)), | |
5558 | integer_zero_node))); | |
1d300e19 KG |
5559 | default: |
5560 | break; | |
e9a25f70 JL |
5561 | } |
5562 | } | |
5563 | } | |
5564 | ||
c05a9b68 RS |
5565 | /* If we are comparing an expression that just has comparisons |
5566 | of two integer values, arithmetic expressions of those comparisons, | |
5567 | and constants, we can simplify it. There are only three cases | |
5568 | to check: the two values can either be equal, the first can be | |
5569 | greater, or the second can be greater. Fold the expression for | |
5570 | those three values. Since each value must be 0 or 1, we have | |
5571 | eight possibilities, each of which corresponds to the constant 0 | |
5572 | or 1 or one of the six possible comparisons. | |
5573 | ||
5574 | This handles common cases like (a > b) == 0 but also handles | |
5575 | expressions like ((x > y) - (y > x)) > 0, which supposedly | |
5576 | occur in macroized code. */ | |
5577 | ||
5578 | if (TREE_CODE (arg1) == INTEGER_CST && TREE_CODE (arg0) != INTEGER_CST) | |
5579 | { | |
5580 | tree cval1 = 0, cval2 = 0; | |
35e66bd1 | 5581 | int save_p = 0; |
c05a9b68 | 5582 | |
35e66bd1 | 5583 | if (twoval_comparison_p (arg0, &cval1, &cval2, &save_p) |
c05a9b68 RS |
5584 | /* Don't handle degenerate cases here; they should already |
5585 | have been handled anyway. */ | |
5586 | && cval1 != 0 && cval2 != 0 | |
5587 | && ! (TREE_CONSTANT (cval1) && TREE_CONSTANT (cval2)) | |
5588 | && TREE_TYPE (cval1) == TREE_TYPE (cval2) | |
7178e3af | 5589 | && INTEGRAL_TYPE_P (TREE_TYPE (cval1)) |
e1ee5cdc RH |
5590 | && TYPE_MAX_VALUE (TREE_TYPE (cval1)) |
5591 | && TYPE_MAX_VALUE (TREE_TYPE (cval2)) | |
c05a9b68 RS |
5592 | && ! operand_equal_p (TYPE_MIN_VALUE (TREE_TYPE (cval1)), |
5593 | TYPE_MAX_VALUE (TREE_TYPE (cval2)), 0)) | |
5594 | { | |
5595 | tree maxval = TYPE_MAX_VALUE (TREE_TYPE (cval1)); | |
5596 | tree minval = TYPE_MIN_VALUE (TREE_TYPE (cval1)); | |
5597 | ||
5598 | /* We can't just pass T to eval_subst in case cval1 or cval2 | |
5599 | was the same as ARG1. */ | |
5600 | ||
5601 | tree high_result | |
5602 | = fold (build (code, type, | |
5603 | eval_subst (arg0, cval1, maxval, cval2, minval), | |
5604 | arg1)); | |
5605 | tree equal_result | |
5606 | = fold (build (code, type, | |
5607 | eval_subst (arg0, cval1, maxval, cval2, maxval), | |
5608 | arg1)); | |
5609 | tree low_result | |
5610 | = fold (build (code, type, | |
5611 | eval_subst (arg0, cval1, minval, cval2, maxval), | |
5612 | arg1)); | |
5613 | ||
5614 | /* All three of these results should be 0 or 1. Confirm they | |
5615 | are. Then use those values to select the proper code | |
5616 | to use. */ | |
5617 | ||
5618 | if ((integer_zerop (high_result) | |
5619 | || integer_onep (high_result)) | |
5620 | && (integer_zerop (equal_result) | |
5621 | || integer_onep (equal_result)) | |
5622 | && (integer_zerop (low_result) | |
5623 | || integer_onep (low_result))) | |
5624 | { | |
5625 | /* Make a 3-bit mask with the high-order bit being the | |
5626 | value for `>', the next for '=', and the low for '<'. */ | |
5627 | switch ((integer_onep (high_result) * 4) | |
5628 | + (integer_onep (equal_result) * 2) | |
5629 | + integer_onep (low_result)) | |
5630 | { | |
5631 | case 0: | |
5632 | /* Always false. */ | |
13837058 | 5633 | return omit_one_operand (type, integer_zero_node, arg0); |
c05a9b68 RS |
5634 | case 1: |
5635 | code = LT_EXPR; | |
5636 | break; | |
5637 | case 2: | |
5638 | code = EQ_EXPR; | |
5639 | break; | |
5640 | case 3: | |
5641 | code = LE_EXPR; | |
5642 | break; | |
5643 | case 4: | |
5644 | code = GT_EXPR; | |
5645 | break; | |
5646 | case 5: | |
5647 | code = NE_EXPR; | |
5648 | break; | |
5649 | case 6: | |
5650 | code = GE_EXPR; | |
5651 | break; | |
5652 | case 7: | |
5653 | /* Always true. */ | |
13837058 | 5654 | return omit_one_operand (type, integer_one_node, arg0); |
c05a9b68 RS |
5655 | } |
5656 | ||
35e66bd1 RK |
5657 | t = build (code, type, cval1, cval2); |
5658 | if (save_p) | |
5659 | return save_expr (t); | |
5660 | else | |
5661 | return fold (t); | |
c05a9b68 RS |
5662 | } |
5663 | } | |
5664 | } | |
5665 | ||
5666 | /* If this is a comparison of a field, we may be able to simplify it. */ | |
5667 | if ((TREE_CODE (arg0) == COMPONENT_REF | |
ebde8a27 RK |
5668 | || TREE_CODE (arg0) == BIT_FIELD_REF) |
5669 | && (code == EQ_EXPR || code == NE_EXPR) | |
5670 | /* Handle the constant case even without -O | |
5671 | to make sure the warnings are given. */ | |
5672 | && (optimize || TREE_CODE (arg1) == INTEGER_CST)) | |
c05a9b68 RS |
5673 | { |
5674 | t1 = optimize_bit_field_compare (code, type, arg0, arg1); | |
5675 | return t1 ? t1 : t; | |
5676 | } | |
5677 | ||
9ec36da5 JL |
5678 | /* If this is a comparison of complex values and either or both sides |
5679 | are a COMPLEX_EXPR or COMPLEX_CST, it is best to split up the | |
5680 | comparisons and join them with a TRUTH_ANDIF_EXPR or TRUTH_ORIF_EXPR. | |
5681 | This may prevent needless evaluations. */ | |
95aa28ae RK |
5682 | if ((code == EQ_EXPR || code == NE_EXPR) |
5683 | && TREE_CODE (TREE_TYPE (arg0)) == COMPLEX_TYPE | |
5684 | && (TREE_CODE (arg0) == COMPLEX_EXPR | |
9ec36da5 JL |
5685 | || TREE_CODE (arg1) == COMPLEX_EXPR |
5686 | || TREE_CODE (arg0) == COMPLEX_CST | |
5687 | || TREE_CODE (arg1) == COMPLEX_CST)) | |
95aa28ae RK |
5688 | { |
5689 | tree subtype = TREE_TYPE (TREE_TYPE (arg0)); | |
f0b8d9aa AS |
5690 | tree real0, imag0, real1, imag1; |
5691 | ||
5692 | arg0 = save_expr (arg0); | |
5693 | arg1 = save_expr (arg1); | |
5694 | real0 = fold (build1 (REALPART_EXPR, subtype, arg0)); | |
5695 | imag0 = fold (build1 (IMAGPART_EXPR, subtype, arg0)); | |
5696 | real1 = fold (build1 (REALPART_EXPR, subtype, arg1)); | |
5697 | imag1 = fold (build1 (IMAGPART_EXPR, subtype, arg1)); | |
95aa28ae RK |
5698 | |
5699 | return fold (build ((code == EQ_EXPR ? TRUTH_ANDIF_EXPR | |
5700 | : TRUTH_ORIF_EXPR), | |
5701 | type, | |
5702 | fold (build (code, type, real0, real1)), | |
5703 | fold (build (code, type, imag0, imag1)))); | |
5704 | } | |
5705 | ||
c05a9b68 RS |
5706 | /* From here on, the only cases we handle are when the result is |
5707 | known to be a constant. | |
5708 | ||
5709 | To compute GT, swap the arguments and do LT. | |
6d716ca8 RS |
5710 | To compute GE, do LT and invert the result. |
5711 | To compute LE, swap the arguments, do LT and invert the result. | |
c05a9b68 RS |
5712 | To compute NE, do EQ and invert the result. |
5713 | ||
5714 | Therefore, the code below must handle only EQ and LT. */ | |
5715 | ||
6d716ca8 RS |
5716 | if (code == LE_EXPR || code == GT_EXPR) |
5717 | { | |
c05a9b68 RS |
5718 | tem = arg0, arg0 = arg1, arg1 = tem; |
5719 | code = swap_tree_comparison (code); | |
5720 | } | |
5721 | ||
5722 | /* Note that it is safe to invert for real values here because we | |
5723 | will check below in the one case that it matters. */ | |
5724 | ||
5725 | invert = 0; | |
5726 | if (code == NE_EXPR || code == GE_EXPR) | |
5727 | { | |
5728 | invert = 1; | |
5729 | code = invert_tree_comparison (code); | |
6d716ca8 RS |
5730 | } |
5731 | ||
5732 | /* Compute a result for LT or EQ if args permit; | |
5733 | otherwise return T. */ | |
c05a9b68 | 5734 | if (TREE_CODE (arg0) == INTEGER_CST && TREE_CODE (arg1) == INTEGER_CST) |
6d716ca8 | 5735 | { |
c05a9b68 RS |
5736 | if (code == EQ_EXPR) |
5737 | t1 = build_int_2 ((TREE_INT_CST_LOW (arg0) | |
5738 | == TREE_INT_CST_LOW (arg1)) | |
5739 | && (TREE_INT_CST_HIGH (arg0) | |
5740 | == TREE_INT_CST_HIGH (arg1)), | |
5741 | 0); | |
6d716ca8 | 5742 | else |
c05a9b68 RS |
5743 | t1 = build_int_2 ((TREE_UNSIGNED (TREE_TYPE (arg0)) |
5744 | ? INT_CST_LT_UNSIGNED (arg0, arg1) | |
5745 | : INT_CST_LT (arg0, arg1)), | |
5746 | 0); | |
6d716ca8 | 5747 | } |
c05a9b68 | 5748 | |
e80c9ccb | 5749 | #if 0 /* This is no longer useful, but breaks some real code. */ |
6d716ca8 RS |
5750 | /* Assume a nonexplicit constant cannot equal an explicit one, |
5751 | since such code would be undefined anyway. | |
5752 | Exception: on sysvr4, using #pragma weak, | |
5753 | a label can come out as 0. */ | |
5754 | else if (TREE_CODE (arg1) == INTEGER_CST | |
5755 | && !integer_zerop (arg1) | |
5756 | && TREE_CONSTANT (arg0) | |
5757 | && TREE_CODE (arg0) == ADDR_EXPR | |
c05a9b68 RS |
5758 | && code == EQ_EXPR) |
5759 | t1 = build_int_2 (0, 0); | |
e80c9ccb | 5760 | #endif |
6d716ca8 | 5761 | /* Two real constants can be compared explicitly. */ |
c05a9b68 | 5762 | else if (TREE_CODE (arg0) == REAL_CST && TREE_CODE (arg1) == REAL_CST) |
6d716ca8 | 5763 | { |
c05a9b68 RS |
5764 | /* If either operand is a NaN, the result is false with two |
5765 | exceptions: First, an NE_EXPR is true on NaNs, but that case | |
5766 | is already handled correctly since we will be inverting the | |
5767 | result for NE_EXPR. Second, if we had inverted a LE_EXPR | |
5768 | or a GE_EXPR into a LT_EXPR, we must return true so that it | |
5769 | will be inverted into false. */ | |
5770 | ||
5771 | if (REAL_VALUE_ISNAN (TREE_REAL_CST (arg0)) | |
5772 | || REAL_VALUE_ISNAN (TREE_REAL_CST (arg1))) | |
5773 | t1 = build_int_2 (invert && code == LT_EXPR, 0); | |
5774 | ||
5775 | else if (code == EQ_EXPR) | |
5776 | t1 = build_int_2 (REAL_VALUES_EQUAL (TREE_REAL_CST (arg0), | |
5777 | TREE_REAL_CST (arg1)), | |
5778 | 0); | |
6d716ca8 | 5779 | else |
c05a9b68 RS |
5780 | t1 = build_int_2 (REAL_VALUES_LESS (TREE_REAL_CST (arg0), |
5781 | TREE_REAL_CST (arg1)), | |
5782 | 0); | |
6d716ca8 RS |
5783 | } |
5784 | ||
c05a9b68 RS |
5785 | if (t1 == NULL_TREE) |
5786 | return t; | |
5787 | ||
5788 | if (invert) | |
5789 | TREE_INT_CST_LOW (t1) ^= 1; | |
5790 | ||
5791 | TREE_TYPE (t1) = type; | |
c651e1e0 MM |
5792 | if (TREE_CODE (type) == BOOLEAN_TYPE) |
5793 | return truthvalue_conversion (t1); | |
c05a9b68 | 5794 | return t1; |
6d716ca8 RS |
5795 | |
5796 | case COND_EXPR: | |
a5e9b124 JW |
5797 | /* Pedantic ANSI C says that a conditional expression is never an lvalue, |
5798 | so all simple results must be passed through pedantic_non_lvalue. */ | |
6d716ca8 | 5799 | if (TREE_CODE (arg0) == INTEGER_CST) |
a5e9b124 JW |
5800 | return pedantic_non_lvalue |
5801 | (TREE_OPERAND (t, (integer_zerop (arg0) ? 2 : 1))); | |
6d716ca8 | 5802 | else if (operand_equal_p (arg1, TREE_OPERAND (expr, 2), 0)) |
4ab3cb65 | 5803 | return pedantic_omit_one_operand (type, arg1, arg0); |
6d716ca8 | 5804 | |
c05a9b68 RS |
5805 | /* If the second operand is zero, invert the comparison and swap |
5806 | the second and third operands. Likewise if the second operand | |
5807 | is constant and the third is not or if the third operand is | |
5808 | equivalent to the first operand of the comparison. */ | |
6d716ca8 | 5809 | |
c05a9b68 RS |
5810 | if (integer_zerop (arg1) |
5811 | || (TREE_CONSTANT (arg1) && ! TREE_CONSTANT (TREE_OPERAND (t, 2))) | |
5812 | || (TREE_CODE_CLASS (TREE_CODE (arg0)) == '<' | |
5813 | && operand_equal_for_comparison_p (TREE_OPERAND (arg0, 0), | |
5814 | TREE_OPERAND (t, 2), | |
5815 | TREE_OPERAND (arg0, 1)))) | |
5816 | { | |
5817 | /* See if this can be inverted. If it can't, possibly because | |
5818 | it was a floating-point inequality comparison, don't do | |
5819 | anything. */ | |
5820 | tem = invert_truthvalue (arg0); | |
6d716ca8 | 5821 | |
c05a9b68 RS |
5822 | if (TREE_CODE (tem) != TRUTH_NOT_EXPR) |
5823 | { | |
cd7ece66 RK |
5824 | t = build (code, type, tem, |
5825 | TREE_OPERAND (t, 2), TREE_OPERAND (t, 1)); | |
5826 | arg0 = tem; | |
a58bd508 MT |
5827 | /* arg1 should be the first argument of the new T. */ |
5828 | arg1 = TREE_OPERAND (t, 1); | |
3a96b5eb | 5829 | STRIP_NOPS (arg1); |
c05a9b68 RS |
5830 | } |
5831 | } | |
6d716ca8 | 5832 | |
c05a9b68 RS |
5833 | /* If we have A op B ? A : C, we may be able to convert this to a |
5834 | simpler expression, depending on the operation and the values | |
b5c52586 RS |
5835 | of B and C. IEEE floating point prevents this though, |
5836 | because A or B might be -0.0 or a NaN. */ | |
6d716ca8 | 5837 | |
c05a9b68 | 5838 | if (TREE_CODE_CLASS (TREE_CODE (arg0)) == '<' |
b5c52586 | 5839 | && (TARGET_FLOAT_FORMAT != IEEE_FLOAT_FORMAT |
fab446b8 RK |
5840 | || ! FLOAT_TYPE_P (TREE_TYPE (TREE_OPERAND (arg0, 0))) |
5841 | || flag_fast_math) | |
c05a9b68 RS |
5842 | && operand_equal_for_comparison_p (TREE_OPERAND (arg0, 0), |
5843 | arg1, TREE_OPERAND (arg0, 1))) | |
6d716ca8 | 5844 | { |
c05a9b68 RS |
5845 | tree arg2 = TREE_OPERAND (t, 2); |
5846 | enum tree_code comp_code = TREE_CODE (arg0); | |
5847 | ||
3a96b5eb RK |
5848 | STRIP_NOPS (arg2); |
5849 | ||
c05a9b68 RS |
5850 | /* If we have A op 0 ? A : -A, this is A, -A, abs (A), or abs (-A), |
5851 | depending on the comparison operation. */ | |
68c6b3a9 DE |
5852 | if ((FLOAT_TYPE_P (TREE_TYPE (TREE_OPERAND (arg0, 1))) |
5853 | ? real_zerop (TREE_OPERAND (arg0, 1)) | |
5854 | : integer_zerop (TREE_OPERAND (arg0, 1))) | |
c05a9b68 RS |
5855 | && TREE_CODE (arg2) == NEGATE_EXPR |
5856 | && operand_equal_p (TREE_OPERAND (arg2, 0), arg1, 0)) | |
5857 | switch (comp_code) | |
5858 | { | |
5859 | case EQ_EXPR: | |
a5e9b124 JW |
5860 | return pedantic_non_lvalue |
5861 | (fold (build1 (NEGATE_EXPR, type, arg1))); | |
c05a9b68 | 5862 | case NE_EXPR: |
a5e9b124 | 5863 | return pedantic_non_lvalue (convert (type, arg1)); |
c05a9b68 RS |
5864 | case GE_EXPR: |
5865 | case GT_EXPR: | |
899f1ed6 RH |
5866 | if (TREE_UNSIGNED (TREE_TYPE (arg1))) |
5867 | arg1 = convert (signed_type (TREE_TYPE (arg1)), arg1); | |
a5e9b124 | 5868 | return pedantic_non_lvalue |
21403f14 RK |
5869 | (convert (type, fold (build1 (ABS_EXPR, |
5870 | TREE_TYPE (arg1), arg1)))); | |
c05a9b68 RS |
5871 | case LE_EXPR: |
5872 | case LT_EXPR: | |
899f1ed6 RH |
5873 | if (TREE_UNSIGNED (TREE_TYPE (arg1))) |
5874 | arg1 = convert (signed_type (TREE_TYPE (arg1)), arg1); | |
a5e9b124 JW |
5875 | return pedantic_non_lvalue |
5876 | (fold (build1 (NEGATE_EXPR, type, | |
21403f14 RK |
5877 | convert (type, |
5878 | fold (build1 (ABS_EXPR, | |
5879 | TREE_TYPE (arg1), | |
5880 | arg1)))))); | |
e9a25f70 JL |
5881 | default: |
5882 | abort (); | |
c05a9b68 | 5883 | } |
6d716ca8 | 5884 | |
c05a9b68 RS |
5885 | /* If this is A != 0 ? A : 0, this is simply A. For ==, it is |
5886 | always zero. */ | |
6d716ca8 | 5887 | |
29ebe69a | 5888 | if (integer_zerop (TREE_OPERAND (arg0, 1)) && integer_zerop (arg2)) |
c05a9b68 RS |
5889 | { |
5890 | if (comp_code == NE_EXPR) | |
a5e9b124 | 5891 | return pedantic_non_lvalue (convert (type, arg1)); |
c05a9b68 | 5892 | else if (comp_code == EQ_EXPR) |
a5e9b124 | 5893 | return pedantic_non_lvalue (convert (type, integer_zero_node)); |
c05a9b68 RS |
5894 | } |
5895 | ||
5896 | /* If this is A op B ? A : B, this is either A, B, min (A, B), | |
5897 | or max (A, B), depending on the operation. */ | |
5898 | ||
5899 | if (operand_equal_for_comparison_p (TREE_OPERAND (arg0, 1), | |
5900 | arg2, TREE_OPERAND (arg0, 0))) | |
3a96b5eb RK |
5901 | { |
5902 | tree comp_op0 = TREE_OPERAND (arg0, 0); | |
5903 | tree comp_op1 = TREE_OPERAND (arg0, 1); | |
5904 | tree comp_type = TREE_TYPE (comp_op0); | |
5905 | ||
5906 | switch (comp_code) | |
5907 | { | |
5908 | case EQ_EXPR: | |
5909 | return pedantic_non_lvalue (convert (type, arg2)); | |
5910 | case NE_EXPR: | |
5911 | return pedantic_non_lvalue (convert (type, arg1)); | |
5912 | case LE_EXPR: | |
5913 | case LT_EXPR: | |
e9a25f70 JL |
5914 | /* In C++ a ?: expression can be an lvalue, so put the |
5915 | operand which will be used if they are equal first | |
5916 | so that we can convert this back to the | |
5917 | corresponding COND_EXPR. */ | |
5918 | return pedantic_non_lvalue | |
5919 | (convert (type, (fold (build (MIN_EXPR, comp_type, | |
5920 | (comp_code == LE_EXPR | |
5921 | ? comp_op0 : comp_op1), | |
5922 | (comp_code == LE_EXPR | |
5923 | ? comp_op1 : comp_op0)))))); | |
88a5cdb8 | 5924 | break; |
3a96b5eb RK |
5925 | case GE_EXPR: |
5926 | case GT_EXPR: | |
e9a25f70 JL |
5927 | return pedantic_non_lvalue |
5928 | (convert (type, fold (build (MAX_EXPR, comp_type, | |
5929 | (comp_code == GE_EXPR | |
5930 | ? comp_op0 : comp_op1), | |
5931 | (comp_code == GE_EXPR | |
5932 | ? comp_op1 : comp_op0))))); | |
88a5cdb8 | 5933 | break; |
e9a25f70 JL |
5934 | default: |
5935 | abort (); | |
3a96b5eb RK |
5936 | } |
5937 | } | |
c05a9b68 RS |
5938 | |
5939 | /* If this is A op C1 ? A : C2 with C1 and C2 constant integers, | |
5940 | we might still be able to simplify this. For example, | |
5941 | if C1 is one less or one more than C2, this might have started | |
53d2fb4f | 5942 | out as a MIN or MAX and been transformed by this function. |
7178e3af | 5943 | Only good for INTEGER_TYPEs, because we need TYPE_MAX_VALUE. */ |
c05a9b68 | 5944 | |
7178e3af | 5945 | if (INTEGRAL_TYPE_P (type) |
53d2fb4f | 5946 | && TREE_CODE (TREE_OPERAND (arg0, 1)) == INTEGER_CST |
c05a9b68 RS |
5947 | && TREE_CODE (arg2) == INTEGER_CST) |
5948 | switch (comp_code) | |
5949 | { | |
5950 | case EQ_EXPR: | |
5951 | /* We can replace A with C1 in this case. */ | |
cd7ece66 RK |
5952 | arg1 = convert (type, TREE_OPERAND (arg0, 1)); |
5953 | t = build (code, type, TREE_OPERAND (t, 0), arg1, | |
5954 | TREE_OPERAND (t, 2)); | |
c05a9b68 RS |
5955 | break; |
5956 | ||
5957 | case LT_EXPR: | |
5958 | /* If C1 is C2 + 1, this is min(A, C2). */ | |
5959 | if (! operand_equal_p (arg2, TYPE_MAX_VALUE (type), 1) | |
5960 | && operand_equal_p (TREE_OPERAND (arg0, 1), | |
5961 | const_binop (PLUS_EXPR, arg2, | |
91d33e36 | 5962 | integer_one_node, 0), 1)) |
a5e9b124 JW |
5963 | return pedantic_non_lvalue |
5964 | (fold (build (MIN_EXPR, type, arg1, arg2))); | |
c05a9b68 RS |
5965 | break; |
5966 | ||
5967 | case LE_EXPR: | |
5968 | /* If C1 is C2 - 1, this is min(A, C2). */ | |
5969 | if (! operand_equal_p (arg2, TYPE_MIN_VALUE (type), 1) | |
5970 | && operand_equal_p (TREE_OPERAND (arg0, 1), | |
5971 | const_binop (MINUS_EXPR, arg2, | |
91d33e36 | 5972 | integer_one_node, 0), 1)) |
a5e9b124 JW |
5973 | return pedantic_non_lvalue |
5974 | (fold (build (MIN_EXPR, type, arg1, arg2))); | |
c05a9b68 RS |
5975 | break; |
5976 | ||
5977 | case GT_EXPR: | |
5978 | /* If C1 is C2 - 1, this is max(A, C2). */ | |
5979 | if (! operand_equal_p (arg2, TYPE_MIN_VALUE (type), 1) | |
5980 | && operand_equal_p (TREE_OPERAND (arg0, 1), | |
5981 | const_binop (MINUS_EXPR, arg2, | |
91d33e36 | 5982 | integer_one_node, 0), 1)) |
a5e9b124 JW |
5983 | return pedantic_non_lvalue |
5984 | (fold (build (MAX_EXPR, type, arg1, arg2))); | |
c05a9b68 RS |
5985 | break; |
5986 | ||
5987 | case GE_EXPR: | |
5988 | /* If C1 is C2 + 1, this is max(A, C2). */ | |
5989 | if (! operand_equal_p (arg2, TYPE_MAX_VALUE (type), 1) | |
5990 | && operand_equal_p (TREE_OPERAND (arg0, 1), | |
5991 | const_binop (PLUS_EXPR, arg2, | |
91d33e36 | 5992 | integer_one_node, 0), 1)) |
a5e9b124 JW |
5993 | return pedantic_non_lvalue |
5994 | (fold (build (MAX_EXPR, type, arg1, arg2))); | |
c05a9b68 | 5995 | break; |
e9a25f70 JL |
5996 | case NE_EXPR: |
5997 | break; | |
5998 | default: | |
5999 | abort (); | |
c05a9b68 | 6000 | } |
6d716ca8 RS |
6001 | } |
6002 | ||
e1f56f62 RK |
6003 | /* If the second operand is simpler than the third, swap them |
6004 | since that produces better jump optimization results. */ | |
6005 | if ((TREE_CONSTANT (arg1) || TREE_CODE_CLASS (TREE_CODE (arg1)) == 'd' | |
6006 | || TREE_CODE (arg1) == SAVE_EXPR) | |
6007 | && ! (TREE_CONSTANT (TREE_OPERAND (t, 2)) | |
6008 | || TREE_CODE_CLASS (TREE_CODE (TREE_OPERAND (t, 2))) == 'd' | |
6009 | || TREE_CODE (TREE_OPERAND (t, 2)) == SAVE_EXPR)) | |
6010 | { | |
6011 | /* See if this can be inverted. If it can't, possibly because | |
6012 | it was a floating-point inequality comparison, don't do | |
6013 | anything. */ | |
6014 | tem = invert_truthvalue (arg0); | |
6015 | ||
6016 | if (TREE_CODE (tem) != TRUTH_NOT_EXPR) | |
6017 | { | |
cd7ece66 RK |
6018 | t = build (code, type, tem, |
6019 | TREE_OPERAND (t, 2), TREE_OPERAND (t, 1)); | |
6020 | arg0 = tem; | |
c479c2ac JL |
6021 | /* arg1 should be the first argument of the new T. */ |
6022 | arg1 = TREE_OPERAND (t, 1); | |
3a96b5eb | 6023 | STRIP_NOPS (arg1); |
e1f56f62 RK |
6024 | } |
6025 | } | |
6026 | ||
c05a9b68 RS |
6027 | /* Convert A ? 1 : 0 to simply A. */ |
6028 | if (integer_onep (TREE_OPERAND (t, 1)) | |
6029 | && integer_zerop (TREE_OPERAND (t, 2)) | |
6030 | /* If we try to convert TREE_OPERAND (t, 0) to our type, the | |
6031 | call to fold will try to move the conversion inside | |
6032 | a COND, which will recurse. In that case, the COND_EXPR | |
6033 | is probably the best choice, so leave it alone. */ | |
6034 | && type == TREE_TYPE (arg0)) | |
a5e9b124 | 6035 | return pedantic_non_lvalue (arg0); |
6d716ca8 | 6036 | |
c05a9b68 RS |
6037 | /* Look for expressions of the form A & 2 ? 2 : 0. The result of this |
6038 | operation is simply A & 2. */ | |
6d716ca8 RS |
6039 | |
6040 | if (integer_zerop (TREE_OPERAND (t, 2)) | |
6041 | && TREE_CODE (arg0) == NE_EXPR | |
6042 | && integer_zerop (TREE_OPERAND (arg0, 1)) | |
c05a9b68 RS |
6043 | && integer_pow2p (arg1) |
6044 | && TREE_CODE (TREE_OPERAND (arg0, 0)) == BIT_AND_EXPR | |
6045 | && operand_equal_p (TREE_OPERAND (TREE_OPERAND (arg0, 0), 1), | |
6046 | arg1, 1)) | |
a5e9b124 | 6047 | return pedantic_non_lvalue (convert (type, TREE_OPERAND (arg0, 0))); |
6d716ca8 | 6048 | |
6d716ca8 RS |
6049 | return t; |
6050 | ||
6051 | case COMPOUND_EXPR: | |
b7647895 JW |
6052 | /* When pedantic, a compound expression can be neither an lvalue |
6053 | nor an integer constant expression. */ | |
6054 | if (TREE_SIDE_EFFECTS (arg0) || pedantic) | |
d023bff9 RS |
6055 | return t; |
6056 | /* Don't let (0, 0) be null pointer constant. */ | |
6057 | if (integer_zerop (arg1)) | |
ff59bfe6 | 6058 | return build1 (NOP_EXPR, TREE_TYPE (arg1), arg1); |
d023bff9 | 6059 | return arg1; |
6d716ca8 | 6060 | |
1cc1b11a RS |
6061 | case COMPLEX_EXPR: |
6062 | if (wins) | |
214d5b84 | 6063 | return build_complex (type, arg0, arg1); |
1cc1b11a RS |
6064 | return t; |
6065 | ||
6066 | case REALPART_EXPR: | |
a333b79f | 6067 | if (TREE_CODE (TREE_TYPE (arg0)) != COMPLEX_TYPE) |
1cc1b11a RS |
6068 | return t; |
6069 | else if (TREE_CODE (arg0) == COMPLEX_EXPR) | |
6070 | return omit_one_operand (type, TREE_OPERAND (arg0, 0), | |
6071 | TREE_OPERAND (arg0, 1)); | |
6072 | else if (TREE_CODE (arg0) == COMPLEX_CST) | |
6073 | return TREE_REALPART (arg0); | |
6074 | else if (TREE_CODE (arg0) == PLUS_EXPR || TREE_CODE (arg0) == MINUS_EXPR) | |
a3279355 RK |
6075 | return fold (build (TREE_CODE (arg0), type, |
6076 | fold (build1 (REALPART_EXPR, type, | |
6077 | TREE_OPERAND (arg0, 0))), | |
6078 | fold (build1 (REALPART_EXPR, | |
6079 | type, TREE_OPERAND (arg0, 1))))); | |
1cc1b11a RS |
6080 | return t; |
6081 | ||
6082 | case IMAGPART_EXPR: | |
a333b79f | 6083 | if (TREE_CODE (TREE_TYPE (arg0)) != COMPLEX_TYPE) |
1cc1b11a RS |
6084 | return convert (type, integer_zero_node); |
6085 | else if (TREE_CODE (arg0) == COMPLEX_EXPR) | |
6086 | return omit_one_operand (type, TREE_OPERAND (arg0, 1), | |
6087 | TREE_OPERAND (arg0, 0)); | |
6088 | else if (TREE_CODE (arg0) == COMPLEX_CST) | |
6089 | return TREE_IMAGPART (arg0); | |
6090 | else if (TREE_CODE (arg0) == PLUS_EXPR || TREE_CODE (arg0) == MINUS_EXPR) | |
a3279355 RK |
6091 | return fold (build (TREE_CODE (arg0), type, |
6092 | fold (build1 (IMAGPART_EXPR, type, | |
6093 | TREE_OPERAND (arg0, 0))), | |
6094 | fold (build1 (IMAGPART_EXPR, type, | |
6095 | TREE_OPERAND (arg0, 1))))); | |
1cc1b11a RS |
6096 | return t; |
6097 | ||
56c98e5b JM |
6098 | /* Pull arithmetic ops out of the CLEANUP_POINT_EXPR where |
6099 | appropriate. */ | |
6100 | case CLEANUP_POINT_EXPR: | |
b7f6588d | 6101 | if (! has_cleanups (arg0)) |
3ffcb234 | 6102 | return TREE_OPERAND (t, 0); |
56c98e5b JM |
6103 | |
6104 | { | |
6105 | enum tree_code code0 = TREE_CODE (arg0); | |
6106 | int kind0 = TREE_CODE_CLASS (code0); | |
6107 | tree arg00 = TREE_OPERAND (arg0, 0); | |
6108 | tree arg01; | |
6109 | ||
0982a4b8 | 6110 | if (kind0 == '1' || code0 == TRUTH_NOT_EXPR) |
56c98e5b JM |
6111 | return fold (build1 (code0, type, |
6112 | fold (build1 (CLEANUP_POINT_EXPR, | |
6113 | TREE_TYPE (arg00), arg00)))); | |
0982a4b8 JM |
6114 | |
6115 | if (kind0 == '<' || kind0 == '2' | |
6116 | || code0 == TRUTH_ANDIF_EXPR || code0 == TRUTH_ORIF_EXPR | |
6117 | || code0 == TRUTH_AND_EXPR || code0 == TRUTH_OR_EXPR | |
6118 | || code0 == TRUTH_XOR_EXPR) | |
6119 | { | |
6120 | arg01 = TREE_OPERAND (arg0, 1); | |
6121 | ||
b7f6588d JM |
6122 | if (TREE_CONSTANT (arg00) |
6123 | || ((code0 == TRUTH_ANDIF_EXPR || code0 == TRUTH_ORIF_EXPR) | |
6124 | && ! has_cleanups (arg00))) | |
0982a4b8 JM |
6125 | return fold (build (code0, type, arg00, |
6126 | fold (build1 (CLEANUP_POINT_EXPR, | |
6127 | TREE_TYPE (arg01), arg01)))); | |
6128 | ||
b7f6588d | 6129 | if (TREE_CONSTANT (arg01)) |
0982a4b8 JM |
6130 | return fold (build (code0, type, |
6131 | fold (build1 (CLEANUP_POINT_EXPR, | |
6132 | TREE_TYPE (arg00), arg00)), | |
6133 | arg01)); | |
6134 | } | |
56c98e5b JM |
6135 | |
6136 | return t; | |
6137 | } | |
6138 | ||
6d716ca8 RS |
6139 | default: |
6140 | return t; | |
6141 | } /* switch (code) */ | |
6142 | } | |
39dfb55a JL |
6143 | |
6144 | /* Determine if first argument is a multiple of second argument. | |
6145 | Return 0 if it is not, or is not easily determined to so be. | |
6146 | ||
6147 | An example of the sort of thing we care about (at this point -- | |
6148 | this routine could surely be made more general, and expanded | |
6149 | to do what the *_DIV_EXPR's fold() cases do now) is discovering | |
6150 | that | |
6151 | ||
6152 | SAVE_EXPR (I) * SAVE_EXPR (J * 8) | |
6153 | ||
6154 | is a multiple of | |
6155 | ||
6156 | SAVE_EXPR (J * 8) | |
6157 | ||
6158 | when we know that the two `SAVE_EXPR (J * 8)' nodes are the | |
6159 | same node (which means they will have the same value at run | |
6160 | time, even though we don't know when they'll be assigned). | |
6161 | ||
6162 | This code also handles discovering that | |
6163 | ||
6164 | SAVE_EXPR (I) * SAVE_EXPR (J * 8) | |
6165 | ||
6166 | is a multiple of | |
6167 | ||
6168 | 8 | |
6169 | ||
6170 | (of course) so we don't have to worry about dealing with a | |
6171 | possible remainder. | |
6172 | ||
6173 | Note that we _look_ inside a SAVE_EXPR only to determine | |
6174 | how it was calculated; it is not safe for fold() to do much | |
6175 | of anything else with the internals of a SAVE_EXPR, since | |
6176 | fold() cannot know when it will be evaluated at run time. | |
6177 | For example, the latter example above _cannot_ be implemented | |
6178 | as | |
6179 | ||
6180 | SAVE_EXPR (I) * J | |
6181 | ||
6182 | or any variant thereof, since the value of J at evaluation time | |
6183 | of the original SAVE_EXPR is not necessarily the same at the time | |
6184 | the new expression is evaluated. The only optimization of this | |
6185 | sort that would be valid is changing | |
6186 | ||
6187 | SAVE_EXPR (I) * SAVE_EXPR (SAVE_EXPR (J) * 8) | |
6188 | divided by | |
6189 | 8 | |
6190 | ||
6191 | to | |
6192 | ||
6193 | SAVE_EXPR (I) * SAVE_EXPR (J) | |
6194 | ||
6195 | (where the same SAVE_EXPR (J) is used in the original and the | |
6196 | transformed version). */ | |
6197 | ||
6198 | static int | |
6199 | multiple_of_p (type, top, bottom) | |
6200 | tree type; | |
6201 | tree top; | |
6202 | tree bottom; | |
6203 | { | |
6204 | if (operand_equal_p (top, bottom, 0)) | |
6205 | return 1; | |
6206 | ||
6207 | if (TREE_CODE (type) != INTEGER_TYPE) | |
6208 | return 0; | |
6209 | ||
6210 | switch (TREE_CODE (top)) | |
6211 | { | |
6212 | case MULT_EXPR: | |
6213 | return (multiple_of_p (type, TREE_OPERAND (top, 0), bottom) | |
6214 | || multiple_of_p (type, TREE_OPERAND (top, 1), bottom)); | |
6215 | ||
6216 | case PLUS_EXPR: | |
6217 | case MINUS_EXPR: | |
6218 | return (multiple_of_p (type, TREE_OPERAND (top, 0), bottom) | |
6219 | && multiple_of_p (type, TREE_OPERAND (top, 1), bottom)); | |
6220 | ||
6221 | case NOP_EXPR: | |
6222 | /* Punt if conversion from non-integral or wider integral type. */ | |
6223 | if ((TREE_CODE (TREE_TYPE (TREE_OPERAND (top, 0))) != INTEGER_TYPE) | |
6224 | || (TYPE_PRECISION (type) | |
6225 | < TYPE_PRECISION (TREE_TYPE (TREE_OPERAND (top, 0))))) | |
6226 | return 0; | |
6227 | /* Fall through. */ | |
6228 | case SAVE_EXPR: | |
6229 | return multiple_of_p (type, TREE_OPERAND (top, 0), bottom); | |
6230 | ||
6231 | case INTEGER_CST: | |
6232 | if ((TREE_CODE (bottom) != INTEGER_CST) | |
6233 | || (tree_int_cst_sgn (top) < 0) | |
6234 | || (tree_int_cst_sgn (bottom) < 0)) | |
6235 | return 0; | |
6236 | return integer_zerop (const_binop (TRUNC_MOD_EXPR, | |
6237 | top, bottom, 0)); | |
6238 | ||
6239 | default: | |
6240 | return 0; | |
6241 | } | |
6242 | } | |
6243 | \f |