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5e6908ea | 1 | /* Expands front end tree to back end RTL for GCC |
4559fd9e | 2 | Copyright (C) 1987, 1988, 1989, 1992, 1993, 1994, 1995, 1996, 1997, |
40e90eac JJ |
3 | 1998, 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009, |
4 | 2010 Free Software Foundation, Inc. | |
28d81abb | 5 | |
1322177d | 6 | This file is part of GCC. |
28d81abb | 7 | |
1322177d LB |
8 | GCC is free software; you can redistribute it and/or modify it under |
9 | the terms of the GNU General Public License as published by the Free | |
9dcd6f09 | 10 | Software Foundation; either version 3, or (at your option) any later |
1322177d | 11 | version. |
28d81abb | 12 | |
1322177d LB |
13 | GCC is distributed in the hope that it will be useful, but WITHOUT ANY |
14 | WARRANTY; without even the implied warranty of MERCHANTABILITY or | |
15 | FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License | |
16 | for more details. | |
28d81abb RK |
17 | |
18 | You should have received a copy of the GNU General Public License | |
9dcd6f09 NC |
19 | along with GCC; see the file COPYING3. If not see |
20 | <http://www.gnu.org/licenses/>. */ | |
28d81abb | 21 | |
28d81abb RK |
22 | /* This file handles the generation of rtl code from tree structure |
23 | above the level of expressions, using subroutines in exp*.c and emit-rtl.c. | |
28d81abb | 24 | The functions whose names start with `expand_' are called by the |
7efcb746 | 25 | expander to generate RTL instructions for various kinds of constructs. */ |
28d81abb RK |
26 | |
27 | #include "config.h" | |
670ee920 | 28 | #include "system.h" |
4977bab6 ZW |
29 | #include "coretypes.h" |
30 | #include "tm.h" | |
ccd043a9 | 31 | |
28d81abb | 32 | #include "rtl.h" |
61158923 | 33 | #include "hard-reg-set.h" |
28d81abb | 34 | #include "tree.h" |
6baf1cc8 | 35 | #include "tm_p.h" |
28d81abb | 36 | #include "flags.h" |
6adb4e3a | 37 | #include "except.h" |
28d81abb | 38 | #include "function.h" |
28d81abb | 39 | #include "insn-config.h" |
28d81abb | 40 | #include "expr.h" |
e78d8e51 | 41 | #include "libfuncs.h" |
28d81abb | 42 | #include "recog.h" |
ca695ac9 | 43 | #include "machmode.h" |
718f9c0f | 44 | #include "diagnostic-core.h" |
10f0ad3d | 45 | #include "toplev.h" |
d6f4ec51 | 46 | #include "output.h" |
87ff9c8e | 47 | #include "ggc.h" |
43577e6b | 48 | #include "langhooks.h" |
969d70ca | 49 | #include "predict.h" |
9bb231fd | 50 | #include "optabs.h" |
61f71b34 | 51 | #include "target.h" |
28ed065e | 52 | #include "gimple.h" |
66fd46b6 | 53 | #include "regs.h" |
6ac1b3a4 | 54 | #include "alloc-pool.h" |
4f1e4960 | 55 | #include "pretty-print.h" |
7a8cba34 SB |
56 | #include "bitmap.h" |
57 | ||
28d81abb RK |
58 | \f |
59 | /* Functions and data structures for expanding case statements. */ | |
60 | ||
61 | /* Case label structure, used to hold info on labels within case | |
62 | statements. We handle "range" labels; for a single-value label | |
63 | as in C, the high and low limits are the same. | |
64 | ||
a6c0a76c SB |
65 | We start with a vector of case nodes sorted in ascending order, and |
66 | the default label as the last element in the vector. Before expanding | |
67 | to RTL, we transform this vector into a list linked via the RIGHT | |
68 | fields in the case_node struct. Nodes with higher case values are | |
69 | later in the list. | |
70 | ||
71 | Switch statements can be output in three forms. A branch table is | |
72 | used if there are more than a few labels and the labels are dense | |
28d81abb RK |
73 | within the range between the smallest and largest case value. If a |
74 | branch table is used, no further manipulations are done with the case | |
75 | node chain. | |
76 | ||
77 | The alternative to the use of a branch table is to generate a series | |
78 | of compare and jump insns. When that is done, we use the LEFT, RIGHT, | |
79 | and PARENT fields to hold a binary tree. Initially the tree is | |
de14fd73 RK |
80 | totally unbalanced, with everything on the right. We balance the tree |
81 | with nodes on the left having lower case values than the parent | |
28d81abb | 82 | and nodes on the right having higher values. We then output the tree |
a6c0a76c SB |
83 | in order. |
84 | ||
85 | For very small, suitable switch statements, we can generate a series | |
86 | of simple bit test and branches instead. */ | |
28d81abb | 87 | |
6ac1b3a4 | 88 | struct case_node |
28d81abb RK |
89 | { |
90 | struct case_node *left; /* Left son in binary tree */ | |
91 | struct case_node *right; /* Right son in binary tree; also node chain */ | |
92 | struct case_node *parent; /* Parent of node in binary tree */ | |
93 | tree low; /* Lowest index value for this label */ | |
94 | tree high; /* Highest index value for this label */ | |
95 | tree code_label; /* Label to jump to when node matches */ | |
96 | }; | |
97 | ||
98 | typedef struct case_node case_node; | |
99 | typedef struct case_node *case_node_ptr; | |
100 | ||
101 | /* These are used by estimate_case_costs and balance_case_nodes. */ | |
102 | ||
103 | /* This must be a signed type, and non-ANSI compilers lack signed char. */ | |
e7749837 | 104 | static short cost_table_[129]; |
28d81abb | 105 | static int use_cost_table; |
2a2137c4 RH |
106 | static int cost_table_initialized; |
107 | ||
108 | /* Special care is needed because we allow -1, but TREE_INT_CST_LOW | |
109 | is unsigned. */ | |
cf403648 | 110 | #define COST_TABLE(I) cost_table_[(unsigned HOST_WIDE_INT) ((I) + 1)] |
28d81abb | 111 | \f |
46c5ad27 | 112 | static int n_occurrences (int, const char *); |
91b4415a | 113 | static bool tree_conflicts_with_clobbers_p (tree, HARD_REG_SET *); |
46c5ad27 | 114 | static void expand_nl_goto_receiver (void); |
46c5ad27 | 115 | static bool check_operand_nalternatives (tree, tree); |
1c384bf1 RH |
116 | static bool check_unique_operand_names (tree, tree, tree); |
117 | static char *resolve_operand_name_1 (char *, tree, tree, tree); | |
ac45df5d | 118 | static void expand_null_return_1 (void); |
46c5ad27 | 119 | static void expand_value_return (rtx); |
46c5ad27 | 120 | static int estimate_case_costs (case_node_ptr); |
46c5ad27 AJ |
121 | static bool lshift_cheap_p (void); |
122 | static int case_bit_test_cmp (const void *, const void *); | |
123 | static void emit_case_bit_tests (tree, tree, tree, tree, case_node_ptr, rtx); | |
46c5ad27 AJ |
124 | static void balance_case_nodes (case_node_ptr *, case_node_ptr); |
125 | static int node_has_low_bound (case_node_ptr, tree); | |
126 | static int node_has_high_bound (case_node_ptr, tree); | |
127 | static int node_is_bounded (case_node_ptr, tree); | |
46c5ad27 | 128 | static void emit_case_nodes (rtx, case_node_ptr, rtx, tree); |
eb172681 | 129 | static struct case_node *add_case_node (struct case_node *, tree, |
6ac1b3a4 | 130 | tree, tree, tree, alloc_pool); |
0cea056b | 131 | |
28d81abb RK |
132 | \f |
133 | /* Return the rtx-label that corresponds to a LABEL_DECL, | |
134 | creating it if necessary. */ | |
135 | ||
136 | rtx | |
46c5ad27 | 137 | label_rtx (tree label) |
28d81abb | 138 | { |
41374e13 | 139 | gcc_assert (TREE_CODE (label) == LABEL_DECL); |
28d81abb | 140 | |
19e7881c | 141 | if (!DECL_RTL_SET_P (label)) |
6de9cd9a DN |
142 | { |
143 | rtx r = gen_label_rtx (); | |
144 | SET_DECL_RTL (label, r); | |
145 | if (FORCED_LABEL (label) || DECL_NONLOCAL (label)) | |
146 | LABEL_PRESERVE_P (r) = 1; | |
147 | } | |
28d81abb | 148 | |
19e7881c | 149 | return DECL_RTL (label); |
28d81abb RK |
150 | } |
151 | ||
046e4e36 ZW |
152 | /* As above, but also put it on the forced-reference list of the |
153 | function that contains it. */ | |
154 | rtx | |
46c5ad27 | 155 | force_label_rtx (tree label) |
046e4e36 ZW |
156 | { |
157 | rtx ref = label_rtx (label); | |
158 | tree function = decl_function_context (label); | |
046e4e36 | 159 | |
41374e13 | 160 | gcc_assert (function); |
046e4e36 | 161 | |
bd60bab2 | 162 | forced_labels = gen_rtx_EXPR_LIST (VOIDmode, ref, forced_labels); |
046e4e36 ZW |
163 | return ref; |
164 | } | |
19e7881c | 165 | |
28d81abb RK |
166 | /* Add an unconditional jump to LABEL as the next sequential instruction. */ |
167 | ||
168 | void | |
46c5ad27 | 169 | emit_jump (rtx label) |
28d81abb RK |
170 | { |
171 | do_pending_stack_adjust (); | |
172 | emit_jump_insn (gen_jump (label)); | |
173 | emit_barrier (); | |
174 | } | |
175 | ||
176 | /* Emit code to jump to the address | |
177 | specified by the pointer expression EXP. */ | |
178 | ||
179 | void | |
46c5ad27 | 180 | expand_computed_goto (tree exp) |
28d81abb | 181 | { |
84217346 | 182 | rtx x = expand_normal (exp); |
ed9a9db1 | 183 | |
5ae6cd0d | 184 | x = convert_memory_address (Pmode, x); |
ffa1a1ce | 185 | |
eb4e1c01 JH |
186 | do_pending_stack_adjust (); |
187 | emit_indirect_jump (x); | |
28d81abb RK |
188 | } |
189 | \f | |
190 | /* Handle goto statements and the labels that they can go to. */ | |
191 | ||
192 | /* Specify the location in the RTL code of a label LABEL, | |
193 | which is a LABEL_DECL tree node. | |
194 | ||
195 | This is used for the kind of label that the user can jump to with a | |
196 | goto statement, and for alternatives of a switch or case statement. | |
197 | RTL labels generated for loops and conditionals don't go through here; | |
198 | they are generated directly at the RTL level, by other functions below. | |
199 | ||
200 | Note that this has nothing to do with defining label *names*. | |
201 | Languages vary in how they do that and what that even means. */ | |
202 | ||
203 | void | |
46c5ad27 | 204 | expand_label (tree label) |
28d81abb | 205 | { |
6de9cd9a | 206 | rtx label_r = label_rtx (label); |
28d81abb RK |
207 | |
208 | do_pending_stack_adjust (); | |
6de9cd9a | 209 | emit_label (label_r); |
28d81abb RK |
210 | if (DECL_NAME (label)) |
211 | LABEL_NAME (DECL_RTL (label)) = IDENTIFIER_POINTER (DECL_NAME (label)); | |
212 | ||
6de9cd9a DN |
213 | if (DECL_NONLOCAL (label)) |
214 | { | |
215 | expand_nl_goto_receiver (); | |
216 | nonlocal_goto_handler_labels | |
217 | = gen_rtx_EXPR_LIST (VOIDmode, label_r, | |
218 | nonlocal_goto_handler_labels); | |
219 | } | |
220 | ||
221 | if (FORCED_LABEL (label)) | |
222 | forced_labels = gen_rtx_EXPR_LIST (VOIDmode, label_r, forced_labels); | |
caf93cb0 | 223 | |
6de9cd9a DN |
224 | if (DECL_NONLOCAL (label) || FORCED_LABEL (label)) |
225 | maybe_set_first_label_num (label_r); | |
28d81abb RK |
226 | } |
227 | ||
28d81abb RK |
228 | /* Generate RTL code for a `goto' statement with target label LABEL. |
229 | LABEL should be a LABEL_DECL tree node that was or will later be | |
230 | defined with `expand_label'. */ | |
231 | ||
232 | void | |
46c5ad27 | 233 | expand_goto (tree label) |
28d81abb | 234 | { |
6de9cd9a DN |
235 | #ifdef ENABLE_CHECKING |
236 | /* Check for a nonlocal goto to a containing function. Should have | |
237 | gotten translated to __builtin_nonlocal_goto. */ | |
238 | tree context = decl_function_context (label); | |
41374e13 | 239 | gcc_assert (!context || context == current_function_decl); |
28d81abb | 240 | #endif |
4b01bd16 | 241 | |
ac45df5d | 242 | emit_jump (label_rtx (label)); |
28d81abb | 243 | } |
2a230e9d BS |
244 | \f |
245 | /* Return the number of times character C occurs in string S. */ | |
246 | static int | |
46c5ad27 | 247 | n_occurrences (int c, const char *s) |
2a230e9d BS |
248 | { |
249 | int n = 0; | |
250 | while (*s) | |
251 | n += (*s++ == c); | |
252 | return n; | |
253 | } | |
28d81abb RK |
254 | \f |
255 | /* Generate RTL for an asm statement (explicit assembler code). | |
4c46ea23 EB |
256 | STRING is a STRING_CST node containing the assembler code text, |
257 | or an ADDR_EXPR containing a STRING_CST. VOL nonzero means the | |
258 | insn is volatile; don't optimize it. */ | |
28d81abb | 259 | |
bac6bfc5 | 260 | static void |
bff4b63d | 261 | expand_asm_loc (tree string, int vol, location_t locus) |
28d81abb | 262 | { |
4c46ea23 EB |
263 | rtx body; |
264 | ||
265 | if (TREE_CODE (string) == ADDR_EXPR) | |
266 | string = TREE_OPERAND (string, 0); | |
267 | ||
bff4b63d AO |
268 | body = gen_rtx_ASM_INPUT_loc (VOIDmode, |
269 | ggc_strdup (TREE_STRING_POINTER (string)), | |
270 | locus); | |
4c46ea23 EB |
271 | |
272 | MEM_VOLATILE_P (body) = vol; | |
28d81abb | 273 | |
4c46ea23 | 274 | emit_insn (body); |
28d81abb RK |
275 | } |
276 | ||
40b18c0a MM |
277 | /* Parse the output constraint pointed to by *CONSTRAINT_P. It is the |
278 | OPERAND_NUMth output operand, indexed from zero. There are NINPUTS | |
279 | inputs and NOUTPUTS outputs to this extended-asm. Upon return, | |
280 | *ALLOWS_MEM will be TRUE iff the constraint allows the use of a | |
281 | memory operand. Similarly, *ALLOWS_REG will be TRUE iff the | |
282 | constraint allows the use of a register operand. And, *IS_INOUT | |
283 | will be true if the operand is read-write, i.e., if it is used as | |
284 | an input as well as an output. If *CONSTRAINT_P is not in | |
285 | canonical form, it will be made canonical. (Note that `+' will be | |
14b493d6 | 286 | replaced with `=' as part of this process.) |
40b18c0a MM |
287 | |
288 | Returns TRUE if all went well; FALSE if an error occurred. */ | |
289 | ||
290 | bool | |
46c5ad27 AJ |
291 | parse_output_constraint (const char **constraint_p, int operand_num, |
292 | int ninputs, int noutputs, bool *allows_mem, | |
293 | bool *allows_reg, bool *is_inout) | |
40b18c0a MM |
294 | { |
295 | const char *constraint = *constraint_p; | |
296 | const char *p; | |
297 | ||
298 | /* Assume the constraint doesn't allow the use of either a register | |
299 | or memory. */ | |
300 | *allows_mem = false; | |
301 | *allows_reg = false; | |
302 | ||
303 | /* Allow the `=' or `+' to not be at the beginning of the string, | |
304 | since it wasn't explicitly documented that way, and there is a | |
305 | large body of code that puts it last. Swap the character to | |
306 | the front, so as not to uglify any place else. */ | |
307 | p = strchr (constraint, '='); | |
308 | if (!p) | |
309 | p = strchr (constraint, '+'); | |
310 | ||
311 | /* If the string doesn't contain an `=', issue an error | |
312 | message. */ | |
313 | if (!p) | |
314 | { | |
971801ff | 315 | error ("output operand constraint lacks %<=%>"); |
40b18c0a MM |
316 | return false; |
317 | } | |
318 | ||
319 | /* If the constraint begins with `+', then the operand is both read | |
320 | from and written to. */ | |
321 | *is_inout = (*p == '+'); | |
322 | ||
40b18c0a | 323 | /* Canonicalize the output constraint so that it begins with `='. */ |
372d72d9 | 324 | if (p != constraint || *is_inout) |
40b18c0a MM |
325 | { |
326 | char *buf; | |
327 | size_t c_len = strlen (constraint); | |
328 | ||
329 | if (p != constraint) | |
d4ee4d25 | 330 | warning (0, "output constraint %qc for operand %d " |
971801ff | 331 | "is not at the beginning", |
40b18c0a MM |
332 | *p, operand_num); |
333 | ||
334 | /* Make a copy of the constraint. */ | |
1634b18f | 335 | buf = XALLOCAVEC (char, c_len + 1); |
40b18c0a MM |
336 | strcpy (buf, constraint); |
337 | /* Swap the first character and the `=' or `+'. */ | |
338 | buf[p - constraint] = buf[0]; | |
339 | /* Make sure the first character is an `='. (Until we do this, | |
340 | it might be a `+'.) */ | |
341 | buf[0] = '='; | |
342 | /* Replace the constraint with the canonicalized string. */ | |
343 | *constraint_p = ggc_alloc_string (buf, c_len); | |
344 | constraint = *constraint_p; | |
345 | } | |
346 | ||
347 | /* Loop through the constraint string. */ | |
97488870 | 348 | for (p = constraint + 1; *p; p += CONSTRAINT_LEN (*p, p)) |
40b18c0a MM |
349 | switch (*p) |
350 | { | |
351 | case '+': | |
352 | case '=': | |
971801ff JM |
353 | error ("operand constraint contains incorrectly positioned " |
354 | "%<+%> or %<=%>"); | |
40b18c0a | 355 | return false; |
786de7eb | 356 | |
40b18c0a MM |
357 | case '%': |
358 | if (operand_num + 1 == ninputs + noutputs) | |
359 | { | |
971801ff | 360 | error ("%<%%%> constraint used with last operand"); |
40b18c0a MM |
361 | return false; |
362 | } | |
363 | break; | |
364 | ||
a4edaf83 | 365 | case 'V': case TARGET_MEM_CONSTRAINT: case 'o': |
40b18c0a MM |
366 | *allows_mem = true; |
367 | break; | |
368 | ||
369 | case '?': case '!': case '*': case '&': case '#': | |
370 | case 'E': case 'F': case 'G': case 'H': | |
371 | case 's': case 'i': case 'n': | |
372 | case 'I': case 'J': case 'K': case 'L': case 'M': | |
373 | case 'N': case 'O': case 'P': case ',': | |
374 | break; | |
375 | ||
376 | case '0': case '1': case '2': case '3': case '4': | |
377 | case '5': case '6': case '7': case '8': case '9': | |
84b72302 | 378 | case '[': |
40b18c0a MM |
379 | error ("matching constraint not valid in output operand"); |
380 | return false; | |
381 | ||
382 | case '<': case '>': | |
383 | /* ??? Before flow, auto inc/dec insns are not supposed to exist, | |
384 | excepting those that expand_call created. So match memory | |
385 | and hope. */ | |
386 | *allows_mem = true; | |
387 | break; | |
388 | ||
389 | case 'g': case 'X': | |
390 | *allows_reg = true; | |
391 | *allows_mem = true; | |
392 | break; | |
786de7eb | 393 | |
40b18c0a MM |
394 | case 'p': case 'r': |
395 | *allows_reg = true; | |
396 | break; | |
397 | ||
398 | default: | |
399 | if (!ISALPHA (*p)) | |
400 | break; | |
97488870 | 401 | if (REG_CLASS_FROM_CONSTRAINT (*p, p) != NO_REGS) |
40b18c0a | 402 | *allows_reg = true; |
97488870 R |
403 | #ifdef EXTRA_CONSTRAINT_STR |
404 | else if (EXTRA_ADDRESS_CONSTRAINT (*p, p)) | |
ccfc6cc8 | 405 | *allows_reg = true; |
97488870 | 406 | else if (EXTRA_MEMORY_CONSTRAINT (*p, p)) |
ccfc6cc8 | 407 | *allows_mem = true; |
40b18c0a MM |
408 | else |
409 | { | |
410 | /* Otherwise we can't assume anything about the nature of | |
411 | the constraint except that it isn't purely registers. | |
412 | Treat it like "g" and hope for the best. */ | |
413 | *allows_reg = true; | |
414 | *allows_mem = true; | |
415 | } | |
416 | #endif | |
417 | break; | |
418 | } | |
419 | ||
420 | return true; | |
421 | } | |
422 | ||
6be2e1f8 RH |
423 | /* Similar, but for input constraints. */ |
424 | ||
1456deaf | 425 | bool |
46c5ad27 AJ |
426 | parse_input_constraint (const char **constraint_p, int input_num, |
427 | int ninputs, int noutputs, int ninout, | |
428 | const char * const * constraints, | |
429 | bool *allows_mem, bool *allows_reg) | |
6be2e1f8 RH |
430 | { |
431 | const char *constraint = *constraint_p; | |
432 | const char *orig_constraint = constraint; | |
433 | size_t c_len = strlen (constraint); | |
434 | size_t j; | |
f3da0ead | 435 | bool saw_match = false; |
6be2e1f8 RH |
436 | |
437 | /* Assume the constraint doesn't allow the use of either | |
438 | a register or memory. */ | |
439 | *allows_mem = false; | |
440 | *allows_reg = false; | |
441 | ||
442 | /* Make sure constraint has neither `=', `+', nor '&'. */ | |
443 | ||
97488870 | 444 | for (j = 0; j < c_len; j += CONSTRAINT_LEN (constraint[j], constraint+j)) |
6be2e1f8 RH |
445 | switch (constraint[j]) |
446 | { | |
447 | case '+': case '=': case '&': | |
448 | if (constraint == orig_constraint) | |
449 | { | |
971801ff | 450 | error ("input operand constraint contains %qc", constraint[j]); |
6be2e1f8 RH |
451 | return false; |
452 | } | |
453 | break; | |
454 | ||
455 | case '%': | |
456 | if (constraint == orig_constraint | |
457 | && input_num + 1 == ninputs - ninout) | |
458 | { | |
971801ff | 459 | error ("%<%%%> constraint used with last operand"); |
6be2e1f8 RH |
460 | return false; |
461 | } | |
462 | break; | |
463 | ||
a4edaf83 | 464 | case 'V': case TARGET_MEM_CONSTRAINT: case 'o': |
6be2e1f8 RH |
465 | *allows_mem = true; |
466 | break; | |
467 | ||
468 | case '<': case '>': | |
469 | case '?': case '!': case '*': case '#': | |
470 | case 'E': case 'F': case 'G': case 'H': | |
471 | case 's': case 'i': case 'n': | |
472 | case 'I': case 'J': case 'K': case 'L': case 'M': | |
473 | case 'N': case 'O': case 'P': case ',': | |
474 | break; | |
475 | ||
476 | /* Whether or not a numeric constraint allows a register is | |
477 | decided by the matching constraint, and so there is no need | |
478 | to do anything special with them. We must handle them in | |
479 | the default case, so that we don't unnecessarily force | |
480 | operands to memory. */ | |
481 | case '0': case '1': case '2': case '3': case '4': | |
482 | case '5': case '6': case '7': case '8': case '9': | |
483 | { | |
484 | char *end; | |
485 | unsigned long match; | |
486 | ||
f3da0ead JM |
487 | saw_match = true; |
488 | ||
6be2e1f8 RH |
489 | match = strtoul (constraint + j, &end, 10); |
490 | if (match >= (unsigned long) noutputs) | |
491 | { | |
492 | error ("matching constraint references invalid operand number"); | |
493 | return false; | |
494 | } | |
495 | ||
496 | /* Try and find the real constraint for this dup. Only do this | |
497 | if the matching constraint is the only alternative. */ | |
498 | if (*end == '\0' | |
499 | && (j == 0 || (j == 1 && constraint[0] == '%'))) | |
500 | { | |
501 | constraint = constraints[match]; | |
502 | *constraint_p = constraint; | |
503 | c_len = strlen (constraint); | |
504 | j = 0; | |
97488870 R |
505 | /* ??? At the end of the loop, we will skip the first part of |
506 | the matched constraint. This assumes not only that the | |
507 | other constraint is an output constraint, but also that | |
508 | the '=' or '+' come first. */ | |
6be2e1f8 RH |
509 | break; |
510 | } | |
511 | else | |
512 | j = end - constraint; | |
97488870 R |
513 | /* Anticipate increment at end of loop. */ |
514 | j--; | |
6be2e1f8 RH |
515 | } |
516 | /* Fall through. */ | |
517 | ||
518 | case 'p': case 'r': | |
519 | *allows_reg = true; | |
520 | break; | |
521 | ||
522 | case 'g': case 'X': | |
523 | *allows_reg = true; | |
524 | *allows_mem = true; | |
525 | break; | |
526 | ||
527 | default: | |
528 | if (! ISALPHA (constraint[j])) | |
529 | { | |
971801ff | 530 | error ("invalid punctuation %qc in constraint", constraint[j]); |
6be2e1f8 RH |
531 | return false; |
532 | } | |
97488870 R |
533 | if (REG_CLASS_FROM_CONSTRAINT (constraint[j], constraint + j) |
534 | != NO_REGS) | |
6be2e1f8 | 535 | *allows_reg = true; |
97488870 R |
536 | #ifdef EXTRA_CONSTRAINT_STR |
537 | else if (EXTRA_ADDRESS_CONSTRAINT (constraint[j], constraint + j)) | |
ccfc6cc8 | 538 | *allows_reg = true; |
97488870 | 539 | else if (EXTRA_MEMORY_CONSTRAINT (constraint[j], constraint + j)) |
ccfc6cc8 | 540 | *allows_mem = true; |
6be2e1f8 RH |
541 | else |
542 | { | |
543 | /* Otherwise we can't assume anything about the nature of | |
544 | the constraint except that it isn't purely registers. | |
545 | Treat it like "g" and hope for the best. */ | |
546 | *allows_reg = true; | |
547 | *allows_mem = true; | |
548 | } | |
549 | #endif | |
550 | break; | |
551 | } | |
552 | ||
f3da0ead | 553 | if (saw_match && !*allows_reg) |
d4ee4d25 | 554 | warning (0, "matching constraint does not allow a register"); |
f3da0ead | 555 | |
6be2e1f8 RH |
556 | return true; |
557 | } | |
558 | ||
91b4415a R |
559 | /* Return DECL iff there's an overlap between *REGS and DECL, where DECL |
560 | can be an asm-declared register. Called via walk_tree. */ | |
acb5d088 | 561 | |
91b4415a R |
562 | static tree |
563 | decl_overlaps_hard_reg_set_p (tree *declp, int *walk_subtrees ATTRIBUTE_UNUSED, | |
564 | void *data) | |
acb5d088 | 565 | { |
91b4415a | 566 | tree decl = *declp; |
1634b18f | 567 | const HARD_REG_SET *const regs = (const HARD_REG_SET *) data; |
91b4415a | 568 | |
3f2de3dc | 569 | if (TREE_CODE (decl) == VAR_DECL) |
acb5d088 | 570 | { |
3f2de3dc | 571 | if (DECL_HARD_REGISTER (decl) |
91b4415a R |
572 | && REG_P (DECL_RTL (decl)) |
573 | && REGNO (DECL_RTL (decl)) < FIRST_PSEUDO_REGISTER) | |
574 | { | |
575 | rtx reg = DECL_RTL (decl); | |
09e18274 RS |
576 | |
577 | if (overlaps_hard_reg_set_p (*regs, GET_MODE (reg), REGNO (reg))) | |
578 | return decl; | |
91b4415a R |
579 | } |
580 | walk_subtrees = 0; | |
61158923 | 581 | } |
3f2de3dc | 582 | else if (TYPE_P (decl) || TREE_CODE (decl) == PARM_DECL) |
91b4415a R |
583 | walk_subtrees = 0; |
584 | return NULL_TREE; | |
61158923 HPN |
585 | } |
586 | ||
91b4415a R |
587 | /* If there is an overlap between *REGS and DECL, return the first overlap |
588 | found. */ | |
589 | tree | |
590 | tree_overlaps_hard_reg_set (tree decl, HARD_REG_SET *regs) | |
591 | { | |
592 | return walk_tree (&decl, decl_overlaps_hard_reg_set_p, regs, NULL); | |
593 | } | |
61158923 HPN |
594 | |
595 | /* Check for overlap between registers marked in CLOBBERED_REGS and | |
91b4415a R |
596 | anything inappropriate in T. Emit error and return the register |
597 | variable definition for error, NULL_TREE for ok. */ | |
61158923 HPN |
598 | |
599 | static bool | |
91b4415a | 600 | tree_conflicts_with_clobbers_p (tree t, HARD_REG_SET *clobbered_regs) |
61158923 HPN |
601 | { |
602 | /* Conflicts between asm-declared register variables and the clobber | |
603 | list are not allowed. */ | |
91b4415a R |
604 | tree overlap = tree_overlaps_hard_reg_set (t, clobbered_regs); |
605 | ||
606 | if (overlap) | |
61158923 | 607 | { |
4f1e4960 JM |
608 | error ("asm-specifier for variable %qE conflicts with asm clobber list", |
609 | DECL_NAME (overlap)); | |
61158923 HPN |
610 | |
611 | /* Reset registerness to stop multiple errors emitted for a single | |
612 | variable. */ | |
91b4415a | 613 | DECL_REGISTER (overlap) = 0; |
61158923 | 614 | return true; |
acb5d088 | 615 | } |
61158923 | 616 | |
acb5d088 HPN |
617 | return false; |
618 | } | |
619 | ||
28d81abb RK |
620 | /* Generate RTL for an asm statement with arguments. |
621 | STRING is the instruction template. | |
622 | OUTPUTS is a list of output arguments (lvalues); INPUTS a list of inputs. | |
623 | Each output or input has an expression in the TREE_VALUE and | |
fa10beec | 624 | a tree list in TREE_PURPOSE which in turn contains a constraint |
786de7eb | 625 | name in TREE_VALUE (or NULL_TREE) and a constraint string |
2ec37136 | 626 | in TREE_PURPOSE. |
28d81abb RK |
627 | CLOBBERS is a list of STRING_CST nodes each naming a hard register |
628 | that is clobbered by this insn. | |
629 | ||
630 | Not all kinds of lvalue that may appear in OUTPUTS can be stored directly. | |
631 | Some elements of OUTPUTS may be replaced with trees representing temporary | |
632 | values. The caller should copy those temporary values to the originally | |
633 | specified lvalues. | |
634 | ||
635 | VOL nonzero means the insn is volatile; don't optimize it. */ | |
636 | ||
bac6bfc5 | 637 | static void |
46c5ad27 | 638 | expand_asm_operands (tree string, tree outputs, tree inputs, |
1c384bf1 | 639 | tree clobbers, tree labels, int vol, location_t locus) |
28d81abb | 640 | { |
1c384bf1 | 641 | rtvec argvec, constraintvec, labelvec; |
28d81abb RK |
642 | rtx body; |
643 | int ninputs = list_length (inputs); | |
644 | int noutputs = list_length (outputs); | |
1c384bf1 | 645 | int nlabels = list_length (labels); |
6be2e1f8 | 646 | int ninout; |
b4ccaa16 | 647 | int nclobbers; |
acb5d088 HPN |
648 | HARD_REG_SET clobbered_regs; |
649 | int clobber_conflict_found = 0; | |
28d81abb | 650 | tree tail; |
7dc8b126 | 651 | tree t; |
b3694847 | 652 | int i; |
28d81abb | 653 | /* Vector of RTX's of evaluated output operands. */ |
1634b18f KG |
654 | rtx *output_rtx = XALLOCAVEC (rtx, noutputs); |
655 | int *inout_opnum = XALLOCAVEC (int, noutputs); | |
656 | rtx *real_output_rtx = XALLOCAVEC (rtx, noutputs); | |
657 | enum machine_mode *inout_mode = XALLOCAVEC (enum machine_mode, noutputs); | |
658 | const char **constraints = XALLOCAVEC (const char *, noutputs + ninputs); | |
1b3d8f8a | 659 | int old_generating_concat_p = generating_concat_p; |
28d81abb | 660 | |
e5e809f4 | 661 | /* An ASM with no outputs needs to be treated as volatile, for now. */ |
296f8acc JL |
662 | if (noutputs == 0) |
663 | vol = 1; | |
664 | ||
84b72302 RH |
665 | if (! check_operand_nalternatives (outputs, inputs)) |
666 | return; | |
667 | ||
1c384bf1 | 668 | string = resolve_asm_operand_names (string, outputs, inputs, labels); |
7dc8b126 JM |
669 | |
670 | /* Collect constraints. */ | |
671 | i = 0; | |
672 | for (t = outputs; t ; t = TREE_CHAIN (t), i++) | |
673 | constraints[i] = TREE_STRING_POINTER (TREE_VALUE (TREE_PURPOSE (t))); | |
674 | for (t = inputs; t ; t = TREE_CHAIN (t), i++) | |
675 | constraints[i] = TREE_STRING_POINTER (TREE_VALUE (TREE_PURPOSE (t))); | |
84b72302 | 676 | |
57bcb97a RH |
677 | /* Sometimes we wish to automatically clobber registers across an asm. |
678 | Case in point is when the i386 backend moved from cc0 to a hard reg -- | |
f63d1bf7 | 679 | maintaining source-level compatibility means automatically clobbering |
57bcb97a | 680 | the flags register. */ |
61158923 | 681 | clobbers = targetm.md_asm_clobbers (outputs, inputs, clobbers); |
57bcb97a | 682 | |
b4ccaa16 RS |
683 | /* Count the number of meaningful clobbered registers, ignoring what |
684 | we would ignore later. */ | |
685 | nclobbers = 0; | |
acb5d088 | 686 | CLEAR_HARD_REG_SET (clobbered_regs); |
b4ccaa16 RS |
687 | for (tail = clobbers; tail; tail = TREE_CHAIN (tail)) |
688 | { | |
123b24e7 VR |
689 | const char *regname; |
690 | ||
691 | if (TREE_VALUE (tail) == error_mark_node) | |
692 | return; | |
693 | regname = TREE_STRING_POINTER (TREE_VALUE (tail)); | |
14a774a9 | 694 | |
c09e6498 RS |
695 | i = decode_reg_name (regname); |
696 | if (i >= 0 || i == -4) | |
b4ccaa16 | 697 | ++nclobbers; |
7859e3ac | 698 | else if (i == -2) |
971801ff | 699 | error ("unknown register name %qs in %<asm%>", regname); |
acb5d088 HPN |
700 | |
701 | /* Mark clobbered registers. */ | |
702 | if (i >= 0) | |
e54b4cae | 703 | { |
ea4b7848 | 704 | /* Clobbering the PIC register is an error. */ |
fc555370 | 705 | if (i == (int) PIC_OFFSET_TABLE_REGNUM) |
e54b4cae | 706 | { |
971801ff | 707 | error ("PIC register %qs clobbered in %<asm%>", regname); |
e54b4cae EB |
708 | return; |
709 | } | |
710 | ||
711 | SET_HARD_REG_BIT (clobbered_regs, i); | |
712 | } | |
b4ccaa16 RS |
713 | } |
714 | ||
6be2e1f8 RH |
715 | /* First pass over inputs and outputs checks validity and sets |
716 | mark_addressable if needed. */ | |
717 | ||
718 | ninout = 0; | |
28d81abb RK |
719 | for (i = 0, tail = outputs; tail; tail = TREE_CHAIN (tail), i++) |
720 | { | |
721 | tree val = TREE_VALUE (tail); | |
b50a024d | 722 | tree type = TREE_TYPE (val); |
6be2e1f8 | 723 | const char *constraint; |
40b18c0a MM |
724 | bool is_inout; |
725 | bool allows_reg; | |
726 | bool allows_mem; | |
28d81abb RK |
727 | |
728 | /* If there's an erroneous arg, emit no insn. */ | |
40b18c0a | 729 | if (type == error_mark_node) |
28d81abb RK |
730 | return; |
731 | ||
40b18c0a MM |
732 | /* Try to parse the output constraint. If that fails, there's |
733 | no point in going further. */ | |
6be2e1f8 RH |
734 | constraint = constraints[i]; |
735 | if (!parse_output_constraint (&constraint, i, ninputs, noutputs, | |
736 | &allows_mem, &allows_reg, &is_inout)) | |
737 | return; | |
738 | ||
739 | if (! allows_reg | |
740 | && (allows_mem | |
741 | || is_inout | |
742 | || (DECL_P (val) | |
f8cfc6aa | 743 | && REG_P (DECL_RTL (val)) |
6be2e1f8 | 744 | && GET_MODE (DECL_RTL (val)) != TYPE_MODE (type)))) |
58f986ca | 745 | mark_addressable (val); |
6be2e1f8 RH |
746 | |
747 | if (is_inout) | |
748 | ninout++; | |
749 | } | |
750 | ||
751 | ninputs += ninout; | |
752 | if (ninputs + noutputs > MAX_RECOG_OPERANDS) | |
753 | { | |
971801ff | 754 | error ("more than %d operands in %<asm%>", MAX_RECOG_OPERANDS); |
6be2e1f8 RH |
755 | return; |
756 | } | |
757 | ||
758 | for (i = 0, tail = inputs; tail; i++, tail = TREE_CHAIN (tail)) | |
759 | { | |
760 | bool allows_reg, allows_mem; | |
761 | const char *constraint; | |
762 | ||
763 | /* If there's an erroneous arg, emit no insn, because the ASM_INPUT | |
764 | would get VOIDmode and that could cause a crash in reload. */ | |
765 | if (TREE_TYPE (TREE_VALUE (tail)) == error_mark_node) | |
766 | return; | |
767 | ||
768 | constraint = constraints[i + noutputs]; | |
769 | if (! parse_input_constraint (&constraint, i, ninputs, noutputs, ninout, | |
770 | constraints, &allows_mem, &allows_reg)) | |
40b18c0a | 771 | return; |
d09a75ae | 772 | |
6be2e1f8 | 773 | if (! allows_reg && allows_mem) |
58f986ca | 774 | mark_addressable (TREE_VALUE (tail)); |
6be2e1f8 RH |
775 | } |
776 | ||
777 | /* Second pass evaluates arguments. */ | |
778 | ||
779 | ninout = 0; | |
780 | for (i = 0, tail = outputs; tail; tail = TREE_CHAIN (tail), i++) | |
781 | { | |
782 | tree val = TREE_VALUE (tail); | |
783 | tree type = TREE_TYPE (val); | |
784 | bool is_inout; | |
785 | bool allows_reg; | |
786 | bool allows_mem; | |
5b50aa9d | 787 | rtx op; |
41374e13 | 788 | bool ok; |
6be2e1f8 | 789 | |
41374e13 | 790 | ok = parse_output_constraint (&constraints[i], i, ninputs, |
6be2e1f8 | 791 | noutputs, &allows_mem, &allows_reg, |
41374e13 NS |
792 | &is_inout); |
793 | gcc_assert (ok); | |
6be2e1f8 | 794 | |
d09a75ae RK |
795 | /* If an output operand is not a decl or indirect ref and our constraint |
796 | allows a register, make a temporary to act as an intermediate. | |
797 | Make the asm insn write into that, then our caller will copy it to | |
798 | the real output operand. Likewise for promoted variables. */ | |
28d81abb | 799 | |
1b3d8f8a GK |
800 | generating_concat_p = 0; |
801 | ||
947255ed | 802 | real_output_rtx[i] = NULL_RTX; |
1afbe1c4 RH |
803 | if ((TREE_CODE (val) == INDIRECT_REF |
804 | && allows_mem) | |
2f939d94 | 805 | || (DECL_P (val) |
f8cfc6aa JQ |
806 | && (allows_mem || REG_P (DECL_RTL (val))) |
807 | && ! (REG_P (DECL_RTL (val)) | |
d09a75ae | 808 | && GET_MODE (DECL_RTL (val)) != TYPE_MODE (type))) |
11579f33 | 809 | || ! allows_reg |
2a230e9d | 810 | || is_inout) |
d09a75ae | 811 | { |
5b50aa9d | 812 | op = expand_expr (val, NULL_RTX, VOIDmode, EXPAND_WRITE); |
3c0cb5de | 813 | if (MEM_P (op)) |
5b50aa9d | 814 | op = validize_mem (op); |
d09a75ae | 815 | |
3c0cb5de | 816 | if (! allows_reg && !MEM_P (op)) |
d09a75ae | 817 | error ("output number %d not directly addressable", i); |
3c0cb5de | 818 | if ((! allows_mem && MEM_P (op)) |
5b50aa9d | 819 | || GET_CODE (op) == CONCAT) |
947255ed | 820 | { |
ad76cef8 | 821 | real_output_rtx[i] = op; |
5b50aa9d | 822 | op = gen_reg_rtx (GET_MODE (op)); |
11579f33 | 823 | if (is_inout) |
5b50aa9d | 824 | emit_move_insn (op, real_output_rtx[i]); |
947255ed | 825 | } |
d09a75ae | 826 | } |
b50a024d | 827 | else |
e619bb8d | 828 | { |
5b50aa9d RH |
829 | op = assign_temp (type, 0, 0, 1); |
830 | op = validize_mem (op); | |
2b5bcdee JJ |
831 | if (!MEM_P (op) && TREE_CODE (TREE_VALUE (tail)) == SSA_NAME) |
832 | set_reg_attrs_for_decl_rtl (SSA_NAME_VAR (TREE_VALUE (tail)), op); | |
5b50aa9d | 833 | TREE_VALUE (tail) = make_tree (type, op); |
b50a024d | 834 | } |
5b50aa9d | 835 | output_rtx[i] = op; |
235c5021 | 836 | |
1b3d8f8a GK |
837 | generating_concat_p = old_generating_concat_p; |
838 | ||
2a230e9d | 839 | if (is_inout) |
235c5021 | 840 | { |
6be2e1f8 | 841 | inout_mode[ninout] = TYPE_MODE (type); |
235c5021 RK |
842 | inout_opnum[ninout++] = i; |
843 | } | |
acb5d088 | 844 | |
91b4415a | 845 | if (tree_conflicts_with_clobbers_p (val, &clobbered_regs)) |
acb5d088 | 846 | clobber_conflict_found = 1; |
28d81abb RK |
847 | } |
848 | ||
84b72302 RH |
849 | /* Make vectors for the expression-rtx, constraint strings, |
850 | and named operands. */ | |
28d81abb RK |
851 | |
852 | argvec = rtvec_alloc (ninputs); | |
84b72302 | 853 | constraintvec = rtvec_alloc (ninputs); |
1c384bf1 | 854 | labelvec = rtvec_alloc (nlabels); |
28d81abb | 855 | |
6462bb43 AO |
856 | body = gen_rtx_ASM_OPERANDS ((noutputs == 0 ? VOIDmode |
857 | : GET_MODE (output_rtx[0])), | |
a396f8ae | 858 | ggc_strdup (TREE_STRING_POINTER (string)), |
84b72302 | 859 | empty_string, 0, argvec, constraintvec, |
1c384bf1 | 860 | labelvec, locus); |
c85f7c16 | 861 | |
78418280 | 862 | MEM_VOLATILE_P (body) = vol; |
28d81abb RK |
863 | |
864 | /* Eval the inputs and put them into ARGVEC. | |
865 | Put their constraints into ASM_INPUTs and store in CONSTRAINTS. */ | |
866 | ||
84b72302 | 867 | for (i = 0, tail = inputs; tail; tail = TREE_CHAIN (tail), ++i) |
28d81abb | 868 | { |
6be2e1f8 RH |
869 | bool allows_reg, allows_mem; |
870 | const char *constraint; | |
871 | tree val, type; | |
1f06ee8d | 872 | rtx op; |
41374e13 | 873 | bool ok; |
28d81abb | 874 | |
6be2e1f8 | 875 | constraint = constraints[i + noutputs]; |
41374e13 NS |
876 | ok = parse_input_constraint (&constraint, i, ninputs, noutputs, ninout, |
877 | constraints, &allows_mem, &allows_reg); | |
878 | gcc_assert (ok); | |
2a230e9d | 879 | |
6be2e1f8 | 880 | generating_concat_p = 0; |
65fed0cb | 881 | |
6be2e1f8 RH |
882 | val = TREE_VALUE (tail); |
883 | type = TREE_TYPE (val); | |
6d40c489 RS |
884 | /* EXPAND_INITIALIZER will not generate code for valid initializer |
885 | constants, but will still generate code for other types of operand. | |
886 | This is the behavior we want for constant constraints. */ | |
017e1b43 | 887 | op = expand_expr (val, NULL_RTX, VOIDmode, |
6d40c489 RS |
888 | allows_reg ? EXPAND_NORMAL |
889 | : allows_mem ? EXPAND_MEMORY | |
890 | : EXPAND_INITIALIZER); | |
65fed0cb | 891 | |
1b3d8f8a | 892 | /* Never pass a CONCAT to an ASM. */ |
1b3d8f8a GK |
893 | if (GET_CODE (op) == CONCAT) |
894 | op = force_reg (GET_MODE (op), op); | |
3c0cb5de | 895 | else if (MEM_P (op)) |
5b50aa9d | 896 | op = validize_mem (op); |
1b3d8f8a | 897 | |
eca72963 | 898 | if (asm_operand_ok (op, constraint, NULL) <= 0) |
65fed0cb | 899 | { |
4bbcb8fc | 900 | if (allows_reg && TYPE_MODE (type) != BLKmode) |
6be2e1f8 | 901 | op = force_reg (TYPE_MODE (type), op); |
11579f33 | 902 | else if (!allows_mem) |
d4ee4d25 | 903 | warning (0, "asm operand %d probably doesn%'t match constraints", |
84b72302 | 904 | i + noutputs); |
3c0cb5de | 905 | else if (MEM_P (op)) |
6be2e1f8 | 906 | { |
d50ad6af RH |
907 | /* We won't recognize either volatile memory or memory |
908 | with a queued address as available a memory_operand | |
909 | at this point. Ignore it: clearly this *is* a memory. */ | |
6be2e1f8 | 910 | } |
1f06ee8d | 911 | else |
017e1b43 | 912 | { |
d4ee4d25 | 913 | warning (0, "use of memory input without lvalue in " |
71ed1fdb | 914 | "asm operand %d is deprecated", i + noutputs); |
017e1b43 RH |
915 | |
916 | if (CONSTANT_P (op)) | |
917 | { | |
9c858681 RS |
918 | rtx mem = force_const_mem (TYPE_MODE (type), op); |
919 | if (mem) | |
920 | op = validize_mem (mem); | |
921 | else | |
922 | op = force_reg (TYPE_MODE (type), op); | |
017e1b43 | 923 | } |
f8cfc6aa | 924 | if (REG_P (op) |
9c858681 | 925 | || GET_CODE (op) == SUBREG |
9c858681 | 926 | || GET_CODE (op) == CONCAT) |
017e1b43 RH |
927 | { |
928 | tree qual_type = build_qualified_type (type, | |
929 | (TYPE_QUALS (type) | |
930 | | TYPE_QUAL_CONST)); | |
931 | rtx memloc = assign_temp (qual_type, 1, 1, 1); | |
932 | memloc = validize_mem (memloc); | |
933 | emit_move_insn (memloc, op); | |
934 | op = memloc; | |
935 | } | |
936 | } | |
65fed0cb | 937 | } |
6be2e1f8 | 938 | |
1b3d8f8a | 939 | generating_concat_p = old_generating_concat_p; |
6462bb43 | 940 | ASM_OPERANDS_INPUT (body, i) = op; |
2a230e9d | 941 | |
6462bb43 | 942 | ASM_OPERANDS_INPUT_CONSTRAINT_EXP (body, i) |
b8698a0f | 943 | = gen_rtx_ASM_INPUT (TYPE_MODE (type), |
a396f8ae | 944 | ggc_strdup (constraints[i + noutputs])); |
acb5d088 | 945 | |
91b4415a | 946 | if (tree_conflicts_with_clobbers_p (val, &clobbered_regs)) |
acb5d088 | 947 | clobber_conflict_found = 1; |
28d81abb RK |
948 | } |
949 | ||
14a774a9 RK |
950 | /* Protect all the operands from the queue now that they have all been |
951 | evaluated. */ | |
28d81abb | 952 | |
1b3d8f8a GK |
953 | generating_concat_p = 0; |
954 | ||
4381f7c2 | 955 | /* For in-out operands, copy output rtx to input rtx. */ |
235c5021 RK |
956 | for (i = 0; i < ninout; i++) |
957 | { | |
235c5021 | 958 | int j = inout_opnum[i]; |
84b72302 | 959 | char buffer[16]; |
235c5021 | 960 | |
6462bb43 | 961 | ASM_OPERANDS_INPUT (body, ninputs - ninout + i) |
235c5021 | 962 | = output_rtx[j]; |
84b72302 RH |
963 | |
964 | sprintf (buffer, "%d", j); | |
6462bb43 | 965 | ASM_OPERANDS_INPUT_CONSTRAINT_EXP (body, ninputs - ninout + i) |
485bad26 | 966 | = gen_rtx_ASM_INPUT (inout_mode[i], ggc_strdup (buffer)); |
235c5021 RK |
967 | } |
968 | ||
1c384bf1 RH |
969 | /* Copy labels to the vector. */ |
970 | for (i = 0, tail = labels; i < nlabels; ++i, tail = TREE_CHAIN (tail)) | |
971 | ASM_OPERANDS_LABEL (body, i) | |
972 | = gen_rtx_LABEL_REF (Pmode, label_rtx (TREE_VALUE (tail))); | |
973 | ||
1b3d8f8a GK |
974 | generating_concat_p = old_generating_concat_p; |
975 | ||
28d81abb | 976 | /* Now, for each output, construct an rtx |
84b72302 RH |
977 | (set OUTPUT (asm_operands INSN OUTPUTCONSTRAINT OUTPUTNUMBER |
978 | ARGVEC CONSTRAINTS OPNAMES)) | |
28d81abb RK |
979 | If there is more than one, put them inside a PARALLEL. */ |
980 | ||
1c384bf1 | 981 | if (nlabels > 0 && nclobbers == 0) |
28d81abb | 982 | { |
1c384bf1 RH |
983 | gcc_assert (noutputs == 0); |
984 | emit_jump_insn (body); | |
28d81abb RK |
985 | } |
986 | else if (noutputs == 0 && nclobbers == 0) | |
987 | { | |
988 | /* No output operands: put in a raw ASM_OPERANDS rtx. */ | |
4977bab6 | 989 | emit_insn (body); |
28d81abb | 990 | } |
1c384bf1 RH |
991 | else if (noutputs == 1 && nclobbers == 0) |
992 | { | |
993 | ASM_OPERANDS_OUTPUT_CONSTRAINT (body) = ggc_strdup (constraints[0]); | |
994 | emit_insn (gen_rtx_SET (VOIDmode, output_rtx[0], body)); | |
995 | } | |
28d81abb RK |
996 | else |
997 | { | |
998 | rtx obody = body; | |
999 | int num = noutputs; | |
14a774a9 RK |
1000 | |
1001 | if (num == 0) | |
1002 | num = 1; | |
1003 | ||
38a448ca | 1004 | body = gen_rtx_PARALLEL (VOIDmode, rtvec_alloc (num + nclobbers)); |
28d81abb RK |
1005 | |
1006 | /* For each output operand, store a SET. */ | |
28d81abb RK |
1007 | for (i = 0, tail = outputs; tail; tail = TREE_CHAIN (tail), i++) |
1008 | { | |
1009 | XVECEXP (body, 0, i) | |
38a448ca RH |
1010 | = gen_rtx_SET (VOIDmode, |
1011 | output_rtx[i], | |
c5c76735 | 1012 | gen_rtx_ASM_OPERANDS |
6462bb43 | 1013 | (GET_MODE (output_rtx[i]), |
a396f8ae GK |
1014 | ggc_strdup (TREE_STRING_POINTER (string)), |
1015 | ggc_strdup (constraints[i]), | |
1c384bf1 | 1016 | i, argvec, constraintvec, labelvec, locus)); |
c5c76735 | 1017 | |
28d81abb RK |
1018 | MEM_VOLATILE_P (SET_SRC (XVECEXP (body, 0, i))) = vol; |
1019 | } | |
1020 | ||
1021 | /* If there are no outputs (but there are some clobbers) | |
1022 | store the bare ASM_OPERANDS into the PARALLEL. */ | |
1023 | ||
1024 | if (i == 0) | |
1025 | XVECEXP (body, 0, i++) = obody; | |
1026 | ||
1027 | /* Store (clobber REG) for each clobbered register specified. */ | |
1028 | ||
b4ccaa16 | 1029 | for (tail = clobbers; tail; tail = TREE_CHAIN (tail)) |
28d81abb | 1030 | { |
47ee9bcb | 1031 | const char *regname = TREE_STRING_POINTER (TREE_VALUE (tail)); |
b4ac57ab | 1032 | int j = decode_reg_name (regname); |
acb5d088 | 1033 | rtx clobbered_reg; |
28d81abb | 1034 | |
b4ac57ab | 1035 | if (j < 0) |
28d81abb | 1036 | { |
c09e6498 | 1037 | if (j == -3) /* `cc', which is not a register */ |
dcfedcd0 RK |
1038 | continue; |
1039 | ||
c09e6498 RS |
1040 | if (j == -4) /* `memory', don't cache memory across asm */ |
1041 | { | |
bffc6177 | 1042 | XVECEXP (body, 0, i++) |
38a448ca | 1043 | = gen_rtx_CLOBBER (VOIDmode, |
c5c76735 JL |
1044 | gen_rtx_MEM |
1045 | (BLKmode, | |
1046 | gen_rtx_SCRATCH (VOIDmode))); | |
c09e6498 RS |
1047 | continue; |
1048 | } | |
1049 | ||
956d6950 | 1050 | /* Ignore unknown register, error already signaled. */ |
cc1f5387 | 1051 | continue; |
28d81abb RK |
1052 | } |
1053 | ||
1054 | /* Use QImode since that's guaranteed to clobber just one reg. */ | |
acb5d088 HPN |
1055 | clobbered_reg = gen_rtx_REG (QImode, j); |
1056 | ||
1057 | /* Do sanity check for overlap between clobbers and respectively | |
1058 | input and outputs that hasn't been handled. Such overlap | |
1059 | should have been detected and reported above. */ | |
1060 | if (!clobber_conflict_found) | |
1061 | { | |
1062 | int opno; | |
1063 | ||
1064 | /* We test the old body (obody) contents to avoid tripping | |
1065 | over the under-construction body. */ | |
1066 | for (opno = 0; opno < noutputs; opno++) | |
1067 | if (reg_overlap_mentioned_p (clobbered_reg, output_rtx[opno])) | |
1068 | internal_error ("asm clobber conflict with output operand"); | |
1069 | ||
1070 | for (opno = 0; opno < ninputs - ninout; opno++) | |
1071 | if (reg_overlap_mentioned_p (clobbered_reg, | |
1072 | ASM_OPERANDS_INPUT (obody, opno))) | |
1073 | internal_error ("asm clobber conflict with input operand"); | |
1074 | } | |
1075 | ||
b4ccaa16 | 1076 | XVECEXP (body, 0, i++) |
acb5d088 | 1077 | = gen_rtx_CLOBBER (VOIDmode, clobbered_reg); |
28d81abb RK |
1078 | } |
1079 | ||
1c384bf1 RH |
1080 | if (nlabels > 0) |
1081 | emit_jump_insn (body); | |
1082 | else | |
1083 | emit_insn (body); | |
28d81abb RK |
1084 | } |
1085 | ||
947255ed RH |
1086 | /* For any outputs that needed reloading into registers, spill them |
1087 | back to where they belong. */ | |
1088 | for (i = 0; i < noutputs; ++i) | |
1089 | if (real_output_rtx[i]) | |
1090 | emit_move_insn (real_output_rtx[i], output_rtx[i]); | |
1091 | ||
e3b5732b | 1092 | crtl->has_asm_statement = 1; |
28d81abb RK |
1093 | free_temp_slots (); |
1094 | } | |
84b72302 | 1095 | |
6de9cd9a | 1096 | void |
28ed065e | 1097 | expand_asm_stmt (gimple stmt) |
6de9cd9a | 1098 | { |
28ed065e MM |
1099 | int noutputs; |
1100 | tree outputs, tail, t; | |
6de9cd9a | 1101 | tree *o; |
28ed065e MM |
1102 | size_t i, n; |
1103 | const char *s; | |
1c384bf1 | 1104 | tree str, out, in, cl, labels; |
efd0b0d3 | 1105 | location_t locus = gimple_location (stmt); |
28ed065e MM |
1106 | |
1107 | /* Meh... convert the gimple asm operands into real tree lists. | |
1108 | Eventually we should make all routines work on the vectors instead | |
1109 | of relying on TREE_CHAIN. */ | |
1110 | out = NULL_TREE; | |
1111 | n = gimple_asm_noutputs (stmt); | |
1112 | if (n > 0) | |
1113 | { | |
1114 | t = out = gimple_asm_output_op (stmt, 0); | |
1115 | for (i = 1; i < n; i++) | |
1c384bf1 | 1116 | t = TREE_CHAIN (t) = gimple_asm_output_op (stmt, i); |
28ed065e MM |
1117 | } |
1118 | ||
1119 | in = NULL_TREE; | |
1120 | n = gimple_asm_ninputs (stmt); | |
1121 | if (n > 0) | |
1122 | { | |
1123 | t = in = gimple_asm_input_op (stmt, 0); | |
1124 | for (i = 1; i < n; i++) | |
1c384bf1 | 1125 | t = TREE_CHAIN (t) = gimple_asm_input_op (stmt, i); |
28ed065e MM |
1126 | } |
1127 | ||
1128 | cl = NULL_TREE; | |
1129 | n = gimple_asm_nclobbers (stmt); | |
1130 | if (n > 0) | |
1131 | { | |
1132 | t = cl = gimple_asm_clobber_op (stmt, 0); | |
1133 | for (i = 1; i < n; i++) | |
1c384bf1 RH |
1134 | t = TREE_CHAIN (t) = gimple_asm_clobber_op (stmt, i); |
1135 | } | |
1136 | ||
1137 | labels = NULL_TREE; | |
1138 | n = gimple_asm_nlabels (stmt); | |
1139 | if (n > 0) | |
1140 | { | |
1141 | t = labels = gimple_asm_label_op (stmt, 0); | |
1142 | for (i = 1; i < n; i++) | |
1143 | t = TREE_CHAIN (t) = gimple_asm_label_op (stmt, i); | |
28ed065e | 1144 | } |
6de9cd9a | 1145 | |
28ed065e MM |
1146 | s = gimple_asm_string (stmt); |
1147 | str = build_string (strlen (s), s); | |
1148 | ||
1149 | if (gimple_asm_input_p (stmt)) | |
6de9cd9a | 1150 | { |
efd0b0d3 | 1151 | expand_asm_loc (str, gimple_asm_volatile_p (stmt), locus); |
6de9cd9a DN |
1152 | return; |
1153 | } | |
1154 | ||
28ed065e MM |
1155 | outputs = out; |
1156 | noutputs = gimple_asm_noutputs (stmt); | |
6de9cd9a DN |
1157 | /* o[I] is the place that output number I should be written. */ |
1158 | o = (tree *) alloca (noutputs * sizeof (tree)); | |
1159 | ||
1160 | /* Record the contents of OUTPUTS before it is modified. */ | |
1161 | for (i = 0, tail = outputs; tail; tail = TREE_CHAIN (tail), i++) | |
1162 | o[i] = TREE_VALUE (tail); | |
1163 | ||
1164 | /* Generate the ASM_OPERANDS insn; store into the TREE_VALUEs of | |
1165 | OUTPUTS some trees for where the values were actually stored. */ | |
1c384bf1 | 1166 | expand_asm_operands (str, outputs, in, cl, labels, |
efd0b0d3 | 1167 | gimple_asm_volatile_p (stmt), locus); |
6de9cd9a DN |
1168 | |
1169 | /* Copy all the intermediate outputs into the specified outputs. */ | |
1170 | for (i = 0, tail = outputs; tail; tail = TREE_CHAIN (tail), i++) | |
1171 | { | |
1172 | if (o[i] != TREE_VALUE (tail)) | |
1173 | { | |
79f5e442 | 1174 | expand_assignment (o[i], TREE_VALUE (tail), false); |
6de9cd9a DN |
1175 | free_temp_slots (); |
1176 | ||
1177 | /* Restore the original value so that it's correct the next | |
1178 | time we expand this function. */ | |
1179 | TREE_VALUE (tail) = o[i]; | |
1180 | } | |
1181 | } | |
6de9cd9a DN |
1182 | } |
1183 | ||
84b72302 RH |
1184 | /* A subroutine of expand_asm_operands. Check that all operands have |
1185 | the same number of alternatives. Return true if so. */ | |
1186 | ||
1187 | static bool | |
46c5ad27 | 1188 | check_operand_nalternatives (tree outputs, tree inputs) |
84b72302 RH |
1189 | { |
1190 | if (outputs || inputs) | |
1191 | { | |
1192 | tree tmp = TREE_PURPOSE (outputs ? outputs : inputs); | |
1193 | int nalternatives | |
1194 | = n_occurrences (',', TREE_STRING_POINTER (TREE_VALUE (tmp))); | |
1195 | tree next = inputs; | |
1196 | ||
1197 | if (nalternatives + 1 > MAX_RECOG_ALTERNATIVES) | |
1198 | { | |
971801ff | 1199 | error ("too many alternatives in %<asm%>"); |
84b72302 RH |
1200 | return false; |
1201 | } | |
1202 | ||
1203 | tmp = outputs; | |
1204 | while (tmp) | |
1205 | { | |
1206 | const char *constraint | |
1207 | = TREE_STRING_POINTER (TREE_VALUE (TREE_PURPOSE (tmp))); | |
1208 | ||
1209 | if (n_occurrences (',', constraint) != nalternatives) | |
1210 | { | |
971801ff JM |
1211 | error ("operand constraints for %<asm%> differ " |
1212 | "in number of alternatives"); | |
84b72302 RH |
1213 | return false; |
1214 | } | |
1215 | ||
1216 | if (TREE_CHAIN (tmp)) | |
1217 | tmp = TREE_CHAIN (tmp); | |
1218 | else | |
1219 | tmp = next, next = 0; | |
1220 | } | |
1221 | } | |
1222 | ||
1223 | return true; | |
1224 | } | |
1225 | ||
1226 | /* A subroutine of expand_asm_operands. Check that all operand names | |
1227 | are unique. Return true if so. We rely on the fact that these names | |
1228 | are identifiers, and so have been canonicalized by get_identifier, | |
1229 | so all we need are pointer comparisons. */ | |
1230 | ||
1231 | static bool | |
1c384bf1 | 1232 | check_unique_operand_names (tree outputs, tree inputs, tree labels) |
84b72302 RH |
1233 | { |
1234 | tree i, j; | |
1235 | ||
1236 | for (i = outputs; i ; i = TREE_CHAIN (i)) | |
1237 | { | |
1238 | tree i_name = TREE_PURPOSE (TREE_PURPOSE (i)); | |
1239 | if (! i_name) | |
1240 | continue; | |
1241 | ||
1242 | for (j = TREE_CHAIN (i); j ; j = TREE_CHAIN (j)) | |
fc552851 | 1243 | if (simple_cst_equal (i_name, TREE_PURPOSE (TREE_PURPOSE (j)))) |
84b72302 RH |
1244 | goto failure; |
1245 | } | |
1246 | ||
1247 | for (i = inputs; i ; i = TREE_CHAIN (i)) | |
1248 | { | |
1249 | tree i_name = TREE_PURPOSE (TREE_PURPOSE (i)); | |
1250 | if (! i_name) | |
1251 | continue; | |
1252 | ||
1253 | for (j = TREE_CHAIN (i); j ; j = TREE_CHAIN (j)) | |
fc552851 | 1254 | if (simple_cst_equal (i_name, TREE_PURPOSE (TREE_PURPOSE (j)))) |
84b72302 RH |
1255 | goto failure; |
1256 | for (j = outputs; j ; j = TREE_CHAIN (j)) | |
fc552851 | 1257 | if (simple_cst_equal (i_name, TREE_PURPOSE (TREE_PURPOSE (j)))) |
84b72302 RH |
1258 | goto failure; |
1259 | } | |
1260 | ||
1c384bf1 RH |
1261 | for (i = labels; i ; i = TREE_CHAIN (i)) |
1262 | { | |
1263 | tree i_name = TREE_PURPOSE (i); | |
1264 | if (! i_name) | |
1265 | continue; | |
1266 | ||
1267 | for (j = TREE_CHAIN (i); j ; j = TREE_CHAIN (j)) | |
1268 | if (simple_cst_equal (i_name, TREE_PURPOSE (j))) | |
1269 | goto failure; | |
1270 | for (j = inputs; j ; j = TREE_CHAIN (j)) | |
1271 | if (simple_cst_equal (i_name, TREE_PURPOSE (TREE_PURPOSE (j)))) | |
1272 | goto failure; | |
1273 | } | |
1274 | ||
84b72302 RH |
1275 | return true; |
1276 | ||
1277 | failure: | |
971801ff | 1278 | error ("duplicate asm operand name %qs", |
fc552851 | 1279 | TREE_STRING_POINTER (TREE_PURPOSE (TREE_PURPOSE (i)))); |
84b72302 RH |
1280 | return false; |
1281 | } | |
1282 | ||
1283 | /* A subroutine of expand_asm_operands. Resolve the names of the operands | |
1284 | in *POUTPUTS and *PINPUTS to numbers, and replace the name expansions in | |
1285 | STRING and in the constraints to those numbers. */ | |
1286 | ||
7dc8b126 | 1287 | tree |
1c384bf1 | 1288 | resolve_asm_operand_names (tree string, tree outputs, tree inputs, tree labels) |
84b72302 | 1289 | { |
7dc8b126 | 1290 | char *buffer; |
84b72302 | 1291 | char *p; |
40209195 | 1292 | const char *c; |
84b72302 RH |
1293 | tree t; |
1294 | ||
1c384bf1 | 1295 | check_unique_operand_names (outputs, inputs, labels); |
1456deaf | 1296 | |
7dc8b126 JM |
1297 | /* Substitute [<name>] in input constraint strings. There should be no |
1298 | named operands in output constraints. */ | |
1299 | for (t = inputs; t ; t = TREE_CHAIN (t)) | |
1300 | { | |
40209195 | 1301 | c = TREE_STRING_POINTER (TREE_VALUE (TREE_PURPOSE (t))); |
7dc8b126 JM |
1302 | if (strchr (c, '[') != NULL) |
1303 | { | |
1304 | p = buffer = xstrdup (c); | |
1305 | while ((p = strchr (p, '[')) != NULL) | |
1c384bf1 | 1306 | p = resolve_operand_name_1 (p, outputs, inputs, NULL); |
7dc8b126 JM |
1307 | TREE_VALUE (TREE_PURPOSE (t)) |
1308 | = build_string (strlen (buffer), buffer); | |
1309 | free (buffer); | |
1310 | } | |
1311 | } | |
1312 | ||
40209195 JM |
1313 | /* Now check for any needed substitutions in the template. */ |
1314 | c = TREE_STRING_POINTER (string); | |
1315 | while ((c = strchr (c, '%')) != NULL) | |
84b72302 | 1316 | { |
40209195 JM |
1317 | if (c[1] == '[') |
1318 | break; | |
1319 | else if (ISALPHA (c[1]) && c[2] == '[') | |
1320 | break; | |
7abcb63a RH |
1321 | else |
1322 | { | |
d34b4f64 | 1323 | c += 1 + (c[1] == '%'); |
7abcb63a RH |
1324 | continue; |
1325 | } | |
84b72302 RH |
1326 | } |
1327 | ||
40209195 JM |
1328 | if (c) |
1329 | { | |
1330 | /* OK, we need to make a copy so we can perform the substitutions. | |
1331 | Assume that we will not need extra space--we get to remove '[' | |
1332 | and ']', which means we cannot have a problem until we have more | |
1333 | than 999 operands. */ | |
1334 | buffer = xstrdup (TREE_STRING_POINTER (string)); | |
1335 | p = buffer + (c - TREE_STRING_POINTER (string)); | |
caf93cb0 | 1336 | |
40209195 JM |
1337 | while ((p = strchr (p, '%')) != NULL) |
1338 | { | |
1339 | if (p[1] == '[') | |
1340 | p += 1; | |
1341 | else if (ISALPHA (p[1]) && p[2] == '[') | |
1342 | p += 2; | |
1343 | else | |
1344 | { | |
d34b4f64 | 1345 | p += 1 + (p[1] == '%'); |
40209195 JM |
1346 | continue; |
1347 | } | |
1348 | ||
1c384bf1 | 1349 | p = resolve_operand_name_1 (p, outputs, inputs, labels); |
40209195 JM |
1350 | } |
1351 | ||
1352 | string = build_string (strlen (buffer), buffer); | |
1353 | free (buffer); | |
1354 | } | |
84b72302 | 1355 | |
84b72302 RH |
1356 | return string; |
1357 | } | |
1358 | ||
1359 | /* A subroutine of resolve_operand_names. P points to the '[' for a | |
1360 | potential named operand of the form [<name>]. In place, replace | |
786de7eb | 1361 | the name and brackets with a number. Return a pointer to the |
84b72302 RH |
1362 | balance of the string after substitution. */ |
1363 | ||
1364 | static char * | |
1c384bf1 | 1365 | resolve_operand_name_1 (char *p, tree outputs, tree inputs, tree labels) |
84b72302 RH |
1366 | { |
1367 | char *q; | |
1368 | int op; | |
1369 | tree t; | |
84b72302 RH |
1370 | |
1371 | /* Collect the operand name. */ | |
1c384bf1 | 1372 | q = strchr (++p, ']'); |
84b72302 RH |
1373 | if (!q) |
1374 | { | |
1375 | error ("missing close brace for named operand"); | |
1376 | return strchr (p, '\0'); | |
1377 | } | |
1c384bf1 | 1378 | *q = '\0'; |
84b72302 RH |
1379 | |
1380 | /* Resolve the name to a number. */ | |
1381 | for (op = 0, t = outputs; t ; t = TREE_CHAIN (t), op++) | |
1382 | { | |
fc552851 | 1383 | tree name = TREE_PURPOSE (TREE_PURPOSE (t)); |
1c384bf1 RH |
1384 | if (name && strcmp (TREE_STRING_POINTER (name), p) == 0) |
1385 | goto found; | |
84b72302 RH |
1386 | } |
1387 | for (t = inputs; t ; t = TREE_CHAIN (t), op++) | |
1388 | { | |
fc552851 | 1389 | tree name = TREE_PURPOSE (TREE_PURPOSE (t)); |
1c384bf1 RH |
1390 | if (name && strcmp (TREE_STRING_POINTER (name), p) == 0) |
1391 | goto found; | |
1392 | } | |
1393 | for (t = labels; t ; t = TREE_CHAIN (t), op++) | |
1394 | { | |
1395 | tree name = TREE_PURPOSE (t); | |
1396 | if (name && strcmp (TREE_STRING_POINTER (name), p) == 0) | |
1397 | goto found; | |
84b72302 RH |
1398 | } |
1399 | ||
1c384bf1 | 1400 | error ("undefined named operand %qs", identifier_to_locale (p)); |
84b72302 | 1401 | op = 0; |
84b72302 | 1402 | |
1c384bf1 | 1403 | found: |
84b72302 RH |
1404 | /* Replace the name with the number. Unfortunately, not all libraries |
1405 | get the return value of sprintf correct, so search for the end of the | |
1406 | generated string by hand. */ | |
1c384bf1 | 1407 | sprintf (--p, "%d", op); |
84b72302 RH |
1408 | p = strchr (p, '\0'); |
1409 | ||
1410 | /* Verify the no extra buffer space assumption. */ | |
41374e13 | 1411 | gcc_assert (p <= q); |
84b72302 RH |
1412 | |
1413 | /* Shift the rest of the buffer down to fill the gap. */ | |
1414 | memmove (p, q + 1, strlen (q + 1) + 1); | |
1415 | ||
1416 | return p; | |
1417 | } | |
28d81abb | 1418 | \f |
4dfa0342 | 1419 | /* Generate RTL to evaluate the expression EXP. */ |
28d81abb RK |
1420 | |
1421 | void | |
46c5ad27 | 1422 | expand_expr_stmt (tree exp) |
1574ef13 AO |
1423 | { |
1424 | rtx value; | |
1425 | tree type; | |
b6ec8c5f | 1426 | |
49452c07 | 1427 | value = expand_expr (exp, const0_rtx, VOIDmode, EXPAND_NORMAL); |
1574ef13 | 1428 | type = TREE_TYPE (exp); |
28d81abb RK |
1429 | |
1430 | /* If all we do is reference a volatile value in memory, | |
1431 | copy it to a register to be sure it is actually touched. */ | |
3c0cb5de | 1432 | if (value && MEM_P (value) && TREE_THIS_VOLATILE (exp)) |
28d81abb | 1433 | { |
1574ef13 | 1434 | if (TYPE_MODE (type) == VOIDmode) |
6a5bbbe6 | 1435 | ; |
1574ef13 AO |
1436 | else if (TYPE_MODE (type) != BLKmode) |
1437 | value = copy_to_reg (value); | |
28d81abb | 1438 | else |
ddbe9812 RS |
1439 | { |
1440 | rtx lab = gen_label_rtx (); | |
4381f7c2 | 1441 | |
ddbe9812 | 1442 | /* Compare the value with itself to reference it. */ |
1574ef13 | 1443 | emit_cmp_and_jump_insns (value, value, EQ, |
84217346 | 1444 | expand_normal (TYPE_SIZE (type)), |
d43e0b7d | 1445 | BLKmode, 0, lab); |
ddbe9812 RS |
1446 | emit_label (lab); |
1447 | } | |
28d81abb RK |
1448 | } |
1449 | ||
4dfa0342 | 1450 | /* Free any temporaries used to evaluate this expression. */ |
28d81abb | 1451 | free_temp_slots (); |
28d81abb RK |
1452 | } |
1453 | ||
1454 | /* Warn if EXP contains any computations whose results are not used. | |
caf93cb0 | 1455 | Return 1 if a warning is printed; 0 otherwise. LOCUS is the |
b9861bff | 1456 | (potential) location of the expression. */ |
28d81abb | 1457 | |
150a992a | 1458 | int |
fa233e34 | 1459 | warn_if_unused_value (const_tree exp, location_t locus) |
28d81abb | 1460 | { |
b9861bff | 1461 | restart: |
591baeb0 | 1462 | if (TREE_USED (exp) || TREE_NO_WARNING (exp)) |
28d81abb RK |
1463 | return 0; |
1464 | ||
9790cefd RH |
1465 | /* Don't warn about void constructs. This includes casting to void, |
1466 | void function calls, and statement expressions with a final cast | |
1467 | to void. */ | |
1468 | if (VOID_TYPE_P (TREE_TYPE (exp))) | |
1469 | return 0; | |
1470 | ||
607bdeaa PB |
1471 | if (EXPR_HAS_LOCATION (exp)) |
1472 | locus = EXPR_LOCATION (exp); | |
b9861bff | 1473 | |
28d81abb RK |
1474 | switch (TREE_CODE (exp)) |
1475 | { | |
1476 | case PREINCREMENT_EXPR: | |
1477 | case POSTINCREMENT_EXPR: | |
1478 | case PREDECREMENT_EXPR: | |
1479 | case POSTDECREMENT_EXPR: | |
1480 | case MODIFY_EXPR: | |
1481 | case INIT_EXPR: | |
1482 | case TARGET_EXPR: | |
1483 | case CALL_EXPR: | |
81797aba | 1484 | case TRY_CATCH_EXPR: |
28d81abb RK |
1485 | case WITH_CLEANUP_EXPR: |
1486 | case EXIT_EXPR: | |
d3d6f724 | 1487 | case VA_ARG_EXPR: |
28d81abb RK |
1488 | return 0; |
1489 | ||
1490 | case BIND_EXPR: | |
1491 | /* For a binding, warn if no side effect within it. */ | |
b9861bff RH |
1492 | exp = BIND_EXPR_BODY (exp); |
1493 | goto restart; | |
28d81abb | 1494 | |
de73f171 | 1495 | case SAVE_EXPR: |
92061771 | 1496 | case NON_LVALUE_EXPR: |
b9861bff RH |
1497 | exp = TREE_OPERAND (exp, 0); |
1498 | goto restart; | |
de73f171 | 1499 | |
28d81abb RK |
1500 | case TRUTH_ORIF_EXPR: |
1501 | case TRUTH_ANDIF_EXPR: | |
1502 | /* In && or ||, warn if 2nd operand has no side effect. */ | |
b9861bff RH |
1503 | exp = TREE_OPERAND (exp, 1); |
1504 | goto restart; | |
28d81abb RK |
1505 | |
1506 | case COMPOUND_EXPR: | |
b9861bff | 1507 | if (warn_if_unused_value (TREE_OPERAND (exp, 0), locus)) |
28d81abb | 1508 | return 1; |
4d23e509 RS |
1509 | /* Let people do `(foo (), 0)' without a warning. */ |
1510 | if (TREE_CONSTANT (TREE_OPERAND (exp, 1))) | |
1511 | return 0; | |
b9861bff RH |
1512 | exp = TREE_OPERAND (exp, 1); |
1513 | goto restart; | |
28d81abb | 1514 | |
591baeb0 JM |
1515 | case COND_EXPR: |
1516 | /* If this is an expression with side effects, don't warn; this | |
1517 | case commonly appears in macro expansions. */ | |
1518 | if (TREE_SIDE_EFFECTS (exp)) | |
28d81abb | 1519 | return 0; |
591baeb0 | 1520 | goto warn; |
28d81abb | 1521 | |
d1e1adfb JM |
1522 | case INDIRECT_REF: |
1523 | /* Don't warn about automatic dereferencing of references, since | |
1524 | the user cannot control it. */ | |
1525 | if (TREE_CODE (TREE_TYPE (TREE_OPERAND (exp, 0))) == REFERENCE_TYPE) | |
b9861bff RH |
1526 | { |
1527 | exp = TREE_OPERAND (exp, 0); | |
1528 | goto restart; | |
1529 | } | |
4381f7c2 KH |
1530 | /* Fall through. */ |
1531 | ||
28d81abb | 1532 | default: |
ddbe9812 | 1533 | /* Referencing a volatile value is a side effect, so don't warn. */ |
6615c446 | 1534 | if ((DECL_P (exp) || REFERENCE_CLASS_P (exp)) |
ddbe9812 RS |
1535 | && TREE_THIS_VOLATILE (exp)) |
1536 | return 0; | |
8d5e6e25 RK |
1537 | |
1538 | /* If this is an expression which has no operands, there is no value | |
1539 | to be unused. There are no such language-independent codes, | |
1540 | but front ends may define such. */ | |
5039610b | 1541 | if (EXPRESSION_CLASS_P (exp) && TREE_OPERAND_LENGTH (exp) == 0) |
8d5e6e25 RK |
1542 | return 0; |
1543 | ||
591baeb0 | 1544 | warn: |
fab922b1 | 1545 | warning_at (locus, OPT_Wunused_value, "value computed is not used"); |
28d81abb RK |
1546 | return 1; |
1547 | } | |
1548 | } | |
28d81abb | 1549 | |
28d81abb RK |
1550 | \f |
1551 | /* Generate RTL to return from the current function, with no value. | |
1552 | (That is, we do not do anything about returning any value.) */ | |
1553 | ||
1554 | void | |
46c5ad27 | 1555 | expand_null_return (void) |
28d81abb | 1556 | { |
4381f7c2 | 1557 | /* If this function was declared to return a value, but we |
bd695e1e | 1558 | didn't, clobber the return registers so that they are not |
a1f300c0 | 1559 | propagated live to the rest of the function. */ |
c13fde05 | 1560 | clobber_return_register (); |
28d81abb | 1561 | |
ac45df5d | 1562 | expand_null_return_1 (); |
28d81abb RK |
1563 | } |
1564 | ||
6e3077c6 EB |
1565 | /* Generate RTL to return directly from the current function. |
1566 | (That is, we bypass any return value.) */ | |
1567 | ||
1568 | void | |
1569 | expand_naked_return (void) | |
1570 | { | |
ac45df5d | 1571 | rtx end_label; |
6e3077c6 EB |
1572 | |
1573 | clear_pending_stack_adjust (); | |
1574 | do_pending_stack_adjust (); | |
6e3077c6 | 1575 | |
ac45df5d | 1576 | end_label = naked_return_label; |
6e3077c6 EB |
1577 | if (end_label == 0) |
1578 | end_label = naked_return_label = gen_label_rtx (); | |
ac45df5d RH |
1579 | |
1580 | emit_jump (end_label); | |
6e3077c6 EB |
1581 | } |
1582 | ||
28d81abb RK |
1583 | /* Generate RTL to return from the current function, with value VAL. */ |
1584 | ||
8d800403 | 1585 | static void |
46c5ad27 | 1586 | expand_value_return (rtx val) |
28d81abb | 1587 | { |
666e3ceb | 1588 | /* Copy the value to the return location unless it's already there. */ |
28d81abb | 1589 | |
cde0f3fd PB |
1590 | tree decl = DECL_RESULT (current_function_decl); |
1591 | rtx return_reg = DECL_RTL (decl); | |
28d81abb | 1592 | if (return_reg != val) |
77636079 | 1593 | { |
666e3ceb PB |
1594 | tree funtype = TREE_TYPE (current_function_decl); |
1595 | tree type = TREE_TYPE (decl); | |
1596 | int unsignedp = TYPE_UNSIGNED (type); | |
cde0f3fd | 1597 | enum machine_mode old_mode = DECL_MODE (decl); |
666e3ceb PB |
1598 | enum machine_mode mode = promote_function_mode (type, old_mode, |
1599 | &unsignedp, funtype, 1); | |
cde0f3fd PB |
1600 | |
1601 | if (mode != old_mode) | |
1602 | val = convert_modes (mode, old_mode, val, unsignedp); | |
1603 | ||
14a774a9 | 1604 | if (GET_CODE (return_reg) == PARALLEL) |
666e3ceb | 1605 | emit_group_load (return_reg, val, type, int_size_in_bytes (type)); |
14a774a9 | 1606 | else |
77636079 RS |
1607 | emit_move_insn (return_reg, val); |
1608 | } | |
14a774a9 | 1609 | |
ac45df5d | 1610 | expand_null_return_1 (); |
28d81abb RK |
1611 | } |
1612 | ||
ac45df5d | 1613 | /* Output a return with no value. */ |
28d81abb RK |
1614 | |
1615 | static void | |
ac45df5d | 1616 | expand_null_return_1 (void) |
28d81abb | 1617 | { |
28d81abb RK |
1618 | clear_pending_stack_adjust (); |
1619 | do_pending_stack_adjust (); | |
526c334b | 1620 | emit_jump (return_label); |
28d81abb RK |
1621 | } |
1622 | \f | |
1623 | /* Generate RTL to evaluate the expression RETVAL and return it | |
1624 | from the current function. */ | |
1625 | ||
1626 | void | |
46c5ad27 | 1627 | expand_return (tree retval) |
28d81abb | 1628 | { |
19e7881c | 1629 | rtx result_rtl; |
b3694847 | 1630 | rtx val = 0; |
28d81abb | 1631 | tree retval_rhs; |
28d81abb RK |
1632 | |
1633 | /* If function wants no value, give it none. */ | |
1634 | if (TREE_CODE (TREE_TYPE (TREE_TYPE (current_function_decl))) == VOID_TYPE) | |
1635 | { | |
84217346 | 1636 | expand_normal (retval); |
28d81abb RK |
1637 | expand_null_return (); |
1638 | return; | |
1639 | } | |
1640 | ||
ea11ca7e | 1641 | if (retval == error_mark_node) |
c9407e4c MM |
1642 | { |
1643 | /* Treat this like a return of no value from a function that | |
1644 | returns a value. */ | |
1645 | expand_null_return (); | |
786de7eb | 1646 | return; |
c9407e4c | 1647 | } |
726a989a | 1648 | else if ((TREE_CODE (retval) == MODIFY_EXPR |
ac45df5d | 1649 | || TREE_CODE (retval) == INIT_EXPR) |
726a989a RB |
1650 | && TREE_CODE (TREE_OPERAND (retval, 0)) == RESULT_DECL) |
1651 | retval_rhs = TREE_OPERAND (retval, 1); | |
28d81abb | 1652 | else |
6de9cd9a | 1653 | retval_rhs = retval; |
28d81abb | 1654 | |
19e7881c MM |
1655 | result_rtl = DECL_RTL (DECL_RESULT (current_function_decl)); |
1656 | ||
6f4a43e0 ZW |
1657 | /* If we are returning the RESULT_DECL, then the value has already |
1658 | been stored into it, so we don't have to do anything special. */ | |
1659 | if (TREE_CODE (retval_rhs) == RESULT_DECL) | |
1660 | expand_value_return (result_rtl); | |
1661 | ||
4c485b63 JL |
1662 | /* If the result is an aggregate that is being returned in one (or more) |
1663 | registers, load the registers here. The compiler currently can't handle | |
1664 | copying a BLKmode value into registers. We could put this code in a | |
1665 | more general area (for use by everyone instead of just function | |
1666 | call/return), but until this feature is generally usable it is kept here | |
ac45df5d | 1667 | (and in expand_call). */ |
4c485b63 | 1668 | |
6f4a43e0 | 1669 | else if (retval_rhs != 0 |
726a989a | 1670 | && TYPE_MODE (TREE_TYPE (retval_rhs)) == BLKmode |
6f4a43e0 | 1671 | && REG_P (result_rtl)) |
4c485b63 | 1672 | { |
770ae6cc RK |
1673 | int i; |
1674 | unsigned HOST_WIDE_INT bitpos, xbitpos; | |
c988af2b | 1675 | unsigned HOST_WIDE_INT padding_correction = 0; |
770ae6cc RK |
1676 | unsigned HOST_WIDE_INT bytes |
1677 | = int_size_in_bytes (TREE_TYPE (retval_rhs)); | |
4c485b63 | 1678 | int n_regs = (bytes + UNITS_PER_WORD - 1) / UNITS_PER_WORD; |
770ae6cc RK |
1679 | unsigned int bitsize |
1680 | = MIN (TYPE_ALIGN (TREE_TYPE (retval_rhs)), BITS_PER_WORD); | |
1634b18f | 1681 | rtx *result_pseudos = XALLOCAVEC (rtx, n_regs); |
c16ddde3 | 1682 | rtx result_reg, src = NULL_RTX, dst = NULL_RTX; |
84217346 | 1683 | rtx result_val = expand_normal (retval_rhs); |
af55da56 | 1684 | enum machine_mode tmpmode, result_reg_mode; |
4c485b63 | 1685 | |
2954d7db RK |
1686 | if (bytes == 0) |
1687 | { | |
1688 | expand_null_return (); | |
1689 | return; | |
1690 | } | |
1691 | ||
c988af2b RS |
1692 | /* If the structure doesn't take up a whole number of words, see |
1693 | whether the register value should be padded on the left or on | |
1694 | the right. Set PADDING_CORRECTION to the number of padding | |
1695 | bits needed on the left side. | |
1696 | ||
1697 | In most ABIs, the structure will be returned at the least end of | |
1698 | the register, which translates to right padding on little-endian | |
1699 | targets and left padding on big-endian targets. The opposite | |
1700 | holds if the structure is returned at the most significant | |
1701 | end of the register. */ | |
1702 | if (bytes % UNITS_PER_WORD != 0 | |
1703 | && (targetm.calls.return_in_msb (TREE_TYPE (retval_rhs)) | |
1704 | ? !BYTES_BIG_ENDIAN | |
1705 | : BYTES_BIG_ENDIAN)) | |
1706 | padding_correction = (BITS_PER_WORD - ((bytes % UNITS_PER_WORD) | |
1707 | * BITS_PER_UNIT)); | |
a7f875d7 | 1708 | |
4381f7c2 | 1709 | /* Copy the structure BITSIZE bits at a time. */ |
c988af2b | 1710 | for (bitpos = 0, xbitpos = padding_correction; |
a7f875d7 RK |
1711 | bitpos < bytes * BITS_PER_UNIT; |
1712 | bitpos += bitsize, xbitpos += bitsize) | |
4c485b63 | 1713 | { |
a7f875d7 | 1714 | /* We need a new destination pseudo each time xbitpos is |
c988af2b | 1715 | on a word boundary and when xbitpos == padding_correction |
a7f875d7 RK |
1716 | (the first time through). */ |
1717 | if (xbitpos % BITS_PER_WORD == 0 | |
c988af2b | 1718 | || xbitpos == padding_correction) |
4c485b63 | 1719 | { |
a7f875d7 RK |
1720 | /* Generate an appropriate register. */ |
1721 | dst = gen_reg_rtx (word_mode); | |
1722 | result_pseudos[xbitpos / BITS_PER_WORD] = dst; | |
1723 | ||
8a38ed86 AM |
1724 | /* Clear the destination before we move anything into it. */ |
1725 | emit_move_insn (dst, CONST0_RTX (GET_MODE (dst))); | |
4c485b63 | 1726 | } |
a7f875d7 RK |
1727 | |
1728 | /* We need a new source operand each time bitpos is on a word | |
1729 | boundary. */ | |
1730 | if (bitpos % BITS_PER_WORD == 0) | |
1731 | src = operand_subword_force (result_val, | |
1732 | bitpos / BITS_PER_WORD, | |
1733 | BLKmode); | |
1734 | ||
1735 | /* Use bitpos for the source extraction (left justified) and | |
1736 | xbitpos for the destination store (right justified). */ | |
1737 | store_bit_field (dst, bitsize, xbitpos % BITS_PER_WORD, word_mode, | |
1738 | extract_bit_field (src, bitsize, | |
1739 | bitpos % BITS_PER_WORD, 1, | |
b3520980 | 1740 | NULL_RTX, word_mode, word_mode)); |
4c485b63 JL |
1741 | } |
1742 | ||
c988af2b RS |
1743 | tmpmode = GET_MODE (result_rtl); |
1744 | if (tmpmode == BLKmode) | |
1745 | { | |
1746 | /* Find the smallest integer mode large enough to hold the | |
1747 | entire structure and use that mode instead of BLKmode | |
1748 | on the USE insn for the return register. */ | |
1749 | for (tmpmode = GET_CLASS_NARROWEST_MODE (MODE_INT); | |
1750 | tmpmode != VOIDmode; | |
1751 | tmpmode = GET_MODE_WIDER_MODE (tmpmode)) | |
1752 | /* Have we found a large enough mode? */ | |
1753 | if (GET_MODE_SIZE (tmpmode) >= bytes) | |
1754 | break; | |
4c485b63 | 1755 | |
41374e13 NS |
1756 | /* A suitable mode should have been found. */ |
1757 | gcc_assert (tmpmode != VOIDmode); | |
4c485b63 | 1758 | |
c988af2b RS |
1759 | PUT_MODE (result_rtl, tmpmode); |
1760 | } | |
3ffeb8f1 | 1761 | |
af55da56 JW |
1762 | if (GET_MODE_SIZE (tmpmode) < GET_MODE_SIZE (word_mode)) |
1763 | result_reg_mode = word_mode; | |
1764 | else | |
1765 | result_reg_mode = tmpmode; | |
1766 | result_reg = gen_reg_rtx (result_reg_mode); | |
1767 | ||
3ffeb8f1 | 1768 | for (i = 0; i < n_regs; i++) |
af55da56 | 1769 | emit_move_insn (operand_subword (result_reg, i, 0, result_reg_mode), |
3ffeb8f1 | 1770 | result_pseudos[i]); |
4c485b63 | 1771 | |
af55da56 JW |
1772 | if (tmpmode != result_reg_mode) |
1773 | result_reg = gen_lowpart (tmpmode, result_reg); | |
1774 | ||
4c485b63 JL |
1775 | expand_value_return (result_reg); |
1776 | } | |
7cc8342c RH |
1777 | else if (retval_rhs != 0 |
1778 | && !VOID_TYPE_P (TREE_TYPE (retval_rhs)) | |
f8cfc6aa | 1779 | && (REG_P (result_rtl) |
7cc8342c | 1780 | || (GET_CODE (result_rtl) == PARALLEL))) |
28d81abb | 1781 | { |
14a774a9 RK |
1782 | /* Calculate the return value into a temporary (usually a pseudo |
1783 | reg). */ | |
1da68f56 RK |
1784 | tree ot = TREE_TYPE (DECL_RESULT (current_function_decl)); |
1785 | tree nt = build_qualified_type (ot, TYPE_QUALS (ot) | TYPE_QUAL_CONST); | |
1786 | ||
1787 | val = assign_temp (nt, 0, 0, 1); | |
49452c07 | 1788 | val = expand_expr (retval_rhs, val, GET_MODE (val), EXPAND_NORMAL); |
dd98f85c | 1789 | val = force_not_mem (val); |
ac45df5d | 1790 | /* Return the calculated value. */ |
bef5d8b6 | 1791 | expand_value_return (val); |
28d81abb RK |
1792 | } |
1793 | else | |
1794 | { | |
ac45df5d | 1795 | /* No hard reg used; calculate value into hard return reg. */ |
49452c07 | 1796 | expand_expr (retval, const0_rtx, VOIDmode, EXPAND_NORMAL); |
14a774a9 | 1797 | expand_value_return (result_rtl); |
28d81abb RK |
1798 | } |
1799 | } | |
28d81abb | 1800 | \f |
ba716ac9 BS |
1801 | /* Emit code to restore vital registers at the beginning of a nonlocal goto |
1802 | handler. */ | |
1803 | static void | |
46c5ad27 | 1804 | expand_nl_goto_receiver (void) |
ba716ac9 | 1805 | { |
531ca746 RH |
1806 | rtx chain; |
1807 | ||
6de9cd9a | 1808 | /* Clobber the FP when we get here, so we have to make sure it's |
e292dbb0 | 1809 | marked as used by this function. */ |
c41c1387 | 1810 | emit_use (hard_frame_pointer_rtx); |
e292dbb0 WH |
1811 | |
1812 | /* Mark the static chain as clobbered here so life information | |
1813 | doesn't get messed up for it. */ | |
531ca746 RH |
1814 | chain = targetm.calls.static_chain (current_function_decl, true); |
1815 | if (chain && REG_P (chain)) | |
1816 | emit_clobber (chain); | |
e292dbb0 | 1817 | |
ba716ac9 BS |
1818 | #ifdef HAVE_nonlocal_goto |
1819 | if (! HAVE_nonlocal_goto) | |
1820 | #endif | |
1821 | /* First adjust our frame pointer to its actual value. It was | |
1822 | previously set to the start of the virtual area corresponding to | |
1823 | the stacked variables when we branched here and now needs to be | |
1824 | adjusted to the actual hardware fp value. | |
1825 | ||
1826 | Assignments are to virtual registers are converted by | |
1827 | instantiate_virtual_regs into the corresponding assignment | |
1828 | to the underlying register (fp in this case) that makes | |
1829 | the original assignment true. | |
1830 | So the following insn will actually be | |
1831 | decrementing fp by STARTING_FRAME_OFFSET. */ | |
1832 | emit_move_insn (virtual_stack_vars_rtx, hard_frame_pointer_rtx); | |
1833 | ||
1834 | #if ARG_POINTER_REGNUM != HARD_FRAME_POINTER_REGNUM | |
1835 | if (fixed_regs[ARG_POINTER_REGNUM]) | |
1836 | { | |
1837 | #ifdef ELIMINABLE_REGS | |
1838 | /* If the argument pointer can be eliminated in favor of the | |
1839 | frame pointer, we don't need to restore it. We assume here | |
1840 | that if such an elimination is present, it can always be used. | |
1841 | This is the case on all known machines; if we don't make this | |
1842 | assumption, we do unnecessary saving on many machines. */ | |
8b60264b | 1843 | static const struct elims {const int from, to;} elim_regs[] = ELIMINABLE_REGS; |
ba716ac9 BS |
1844 | size_t i; |
1845 | ||
b6a1cbae | 1846 | for (i = 0; i < ARRAY_SIZE (elim_regs); i++) |
ba716ac9 BS |
1847 | if (elim_regs[i].from == ARG_POINTER_REGNUM |
1848 | && elim_regs[i].to == HARD_FRAME_POINTER_REGNUM) | |
1849 | break; | |
1850 | ||
b6a1cbae | 1851 | if (i == ARRAY_SIZE (elim_regs)) |
ba716ac9 BS |
1852 | #endif |
1853 | { | |
1854 | /* Now restore our arg pointer from the address at which it | |
278ed218 | 1855 | was saved in our stack frame. */ |
2e3f842f | 1856 | emit_move_insn (crtl->args.internal_arg_pointer, |
bd60bab2 | 1857 | copy_to_reg (get_arg_pointer_save_area ())); |
ba716ac9 BS |
1858 | } |
1859 | } | |
1860 | #endif | |
1861 | ||
1862 | #ifdef HAVE_nonlocal_goto_receiver | |
1863 | if (HAVE_nonlocal_goto_receiver) | |
1864 | emit_insn (gen_nonlocal_goto_receiver ()); | |
1865 | #endif | |
e292dbb0 | 1866 | |
6fb5fa3c DB |
1867 | /* We must not allow the code we just generated to be reordered by |
1868 | scheduling. Specifically, the update of the frame pointer must | |
1869 | happen immediately, not later. */ | |
1870 | emit_insn (gen_blockage ()); | |
ba716ac9 | 1871 | } |
28d81abb RK |
1872 | \f |
1873 | /* Generate RTL for the automatic variable declaration DECL. | |
ec5cd386 | 1874 | (Other kinds of declarations are simply ignored if seen here.) */ |
28d81abb RK |
1875 | |
1876 | void | |
46c5ad27 | 1877 | expand_decl (tree decl) |
28d81abb | 1878 | { |
ca695ac9 JB |
1879 | tree type; |
1880 | ||
ca695ac9 | 1881 | type = TREE_TYPE (decl); |
28d81abb | 1882 | |
eabb9ed0 RK |
1883 | /* For a CONST_DECL, set mode, alignment, and sizes from those of the |
1884 | type in case this node is used in a reference. */ | |
1885 | if (TREE_CODE (decl) == CONST_DECL) | |
1886 | { | |
1887 | DECL_MODE (decl) = TYPE_MODE (type); | |
1888 | DECL_ALIGN (decl) = TYPE_ALIGN (type); | |
1889 | DECL_SIZE (decl) = TYPE_SIZE (type); | |
1890 | DECL_SIZE_UNIT (decl) = TYPE_SIZE_UNIT (type); | |
1891 | return; | |
1892 | } | |
28d81abb | 1893 | |
eabb9ed0 RK |
1894 | /* Otherwise, only automatic variables need any expansion done. Static and |
1895 | external variables, and external functions, will be handled by | |
1896 | `assemble_variable' (called from finish_decl). TYPE_DECL requires | |
1897 | nothing. PARM_DECLs are handled in `assign_parms'. */ | |
28d81abb RK |
1898 | if (TREE_CODE (decl) != VAR_DECL) |
1899 | return; | |
eabb9ed0 | 1900 | |
44fe2e80 | 1901 | if (TREE_STATIC (decl) || DECL_EXTERNAL (decl)) |
28d81abb RK |
1902 | return; |
1903 | ||
1904 | /* Create the RTL representation for the variable. */ | |
1905 | ||
1906 | if (type == error_mark_node) | |
19e7881c | 1907 | SET_DECL_RTL (decl, gen_rtx_MEM (BLKmode, const0_rtx)); |
1da68f56 | 1908 | |
28d81abb | 1909 | else if (DECL_SIZE (decl) == 0) |
28d81abb | 1910 | { |
b38f3813 | 1911 | /* Variable with incomplete type. */ |
abde42f7 | 1912 | rtx x; |
28d81abb RK |
1913 | if (DECL_INITIAL (decl) == 0) |
1914 | /* Error message was already done; now avoid a crash. */ | |
abde42f7 | 1915 | x = gen_rtx_MEM (BLKmode, const0_rtx); |
28d81abb RK |
1916 | else |
1917 | /* An initializer is going to decide the size of this array. | |
1918 | Until we know the size, represent its address with a reg. */ | |
abde42f7 | 1919 | x = gen_rtx_MEM (BLKmode, gen_reg_rtx (Pmode)); |
3bdf5ad1 | 1920 | |
abde42f7 JH |
1921 | set_mem_attributes (x, decl, 1); |
1922 | SET_DECL_RTL (decl, x); | |
28d81abb | 1923 | } |
8fff4fc1 | 1924 | else if (use_register_for_decl (decl)) |
28d81abb RK |
1925 | { |
1926 | /* Automatic variable that can go in a register. */ | |
cde0f3fd | 1927 | enum machine_mode reg_mode = promote_decl_mode (decl, NULL); |
98f3b471 | 1928 | |
19e7881c | 1929 | SET_DECL_RTL (decl, gen_reg_rtx (reg_mode)); |
0d4903b8 | 1930 | |
0b068ee9 | 1931 | /* Note if the object is a user variable. */ |
7dc8b126 | 1932 | if (!DECL_ARTIFICIAL (decl)) |
0b068ee9 JL |
1933 | mark_user_reg (DECL_RTL (decl)); |
1934 | ||
61021c2c AP |
1935 | if (POINTER_TYPE_P (type)) |
1936 | mark_reg_pointer (DECL_RTL (decl), | |
1937 | TYPE_ALIGN (TREE_TYPE (TREE_TYPE (decl)))); | |
28d81abb | 1938 | } |
0df15c2c | 1939 | |
b38f3813 | 1940 | else |
28d81abb | 1941 | { |
28d81abb RK |
1942 | rtx oldaddr = 0; |
1943 | rtx addr; | |
0d4903b8 | 1944 | rtx x; |
28d81abb | 1945 | |
b38f3813 EB |
1946 | /* Variable-sized decls are dealt with in the gimplifier. */ |
1947 | gcc_assert (TREE_CODE (DECL_SIZE_UNIT (decl)) == INTEGER_CST); | |
1948 | ||
28d81abb RK |
1949 | /* If we previously made RTL for this decl, it must be an array |
1950 | whose size was determined by the initializer. | |
1951 | The old address was a register; set that register now | |
1952 | to the proper address. */ | |
19e7881c | 1953 | if (DECL_RTL_SET_P (decl)) |
28d81abb | 1954 | { |
41374e13 NS |
1955 | gcc_assert (MEM_P (DECL_RTL (decl))); |
1956 | gcc_assert (REG_P (XEXP (DECL_RTL (decl), 0))); | |
28d81abb RK |
1957 | oldaddr = XEXP (DECL_RTL (decl), 0); |
1958 | } | |
1959 | ||
28d81abb RK |
1960 | /* Set alignment we actually gave this decl. */ |
1961 | DECL_ALIGN (decl) = (DECL_MODE (decl) == BLKmode ? BIGGEST_ALIGNMENT | |
1962 | : GET_MODE_BITSIZE (DECL_MODE (decl))); | |
11cf4d18 | 1963 | DECL_USER_ALIGN (decl) = 0; |
28d81abb | 1964 | |
9432c136 | 1965 | x = assign_temp (decl, 1, 1, 1); |
0d4903b8 RK |
1966 | set_mem_attributes (x, decl, 1); |
1967 | SET_DECL_RTL (decl, x); | |
1968 | ||
28d81abb RK |
1969 | if (oldaddr) |
1970 | { | |
1971 | addr = force_operand (XEXP (DECL_RTL (decl), 0), oldaddr); | |
1972 | if (addr != oldaddr) | |
1973 | emit_move_insn (oldaddr, addr); | |
1974 | } | |
28d81abb | 1975 | } |
28d81abb RK |
1976 | } |
1977 | \f | |
6de9cd9a DN |
1978 | /* Emit code to save the current value of stack. */ |
1979 | rtx | |
1980 | expand_stack_save (void) | |
1981 | { | |
1982 | rtx ret = NULL_RTX; | |
1983 | ||
1984 | do_pending_stack_adjust (); | |
1985 | emit_stack_save (SAVE_BLOCK, &ret, NULL_RTX); | |
1986 | return ret; | |
1987 | } | |
1988 | ||
1989 | /* Emit code to restore the current value of stack. */ | |
1990 | void | |
1991 | expand_stack_restore (tree var) | |
1992 | { | |
b9f9b210 | 1993 | rtx sa = expand_normal (var); |
6de9cd9a | 1994 | |
41ccb5d1 | 1995 | sa = convert_memory_address (Pmode, sa); |
6de9cd9a DN |
1996 | emit_stack_restore (SAVE_BLOCK, sa, NULL_RTX); |
1997 | } | |
28d81abb | 1998 | \f |
7efcb746 PB |
1999 | /* Do the insertion of a case label into case_list. The labels are |
2000 | fed to us in descending order from the sorted vector of case labels used | |
a6c0a76c | 2001 | in the tree part of the middle end. So the list we construct is |
eb172681 RS |
2002 | sorted in ascending order. The bounds on the case range, LOW and HIGH, |
2003 | are converted to case's index type TYPE. */ | |
57641239 | 2004 | |
eb172681 RS |
2005 | static struct case_node * |
2006 | add_case_node (struct case_node *head, tree type, tree low, tree high, | |
6ac1b3a4 | 2007 | tree label, alloc_pool case_node_pool) |
57641239 | 2008 | { |
eb172681 | 2009 | tree min_value, max_value; |
a6c0a76c | 2010 | struct case_node *r; |
57641239 | 2011 | |
eb172681 RS |
2012 | gcc_assert (TREE_CODE (low) == INTEGER_CST); |
2013 | gcc_assert (!high || TREE_CODE (high) == INTEGER_CST); | |
2014 | ||
2015 | min_value = TYPE_MIN_VALUE (type); | |
2016 | max_value = TYPE_MAX_VALUE (type); | |
2017 | ||
56cb9733 MM |
2018 | /* If there's no HIGH value, then this is not a case range; it's |
2019 | just a simple case label. But that's just a degenerate case | |
a6c0a76c SB |
2020 | range. |
2021 | If the bounds are equal, turn this into the one-value case. */ | |
2022 | if (!high || tree_int_cst_equal (low, high)) | |
eb172681 RS |
2023 | { |
2024 | /* If the simple case value is unreachable, ignore it. */ | |
b77aa1f7 AP |
2025 | if ((TREE_CODE (min_value) == INTEGER_CST |
2026 | && tree_int_cst_compare (low, min_value) < 0) | |
2027 | || (TREE_CODE (max_value) == INTEGER_CST | |
2028 | && tree_int_cst_compare (low, max_value) > 0)) | |
eb172681 RS |
2029 | return head; |
2030 | low = fold_convert (type, low); | |
2031 | high = low; | |
2032 | } | |
2033 | else | |
2034 | { | |
2035 | /* If the entire case range is unreachable, ignore it. */ | |
b77aa1f7 AP |
2036 | if ((TREE_CODE (min_value) == INTEGER_CST |
2037 | && tree_int_cst_compare (high, min_value) < 0) | |
2038 | || (TREE_CODE (max_value) == INTEGER_CST | |
2039 | && tree_int_cst_compare (low, max_value) > 0)) | |
eb172681 RS |
2040 | return head; |
2041 | ||
2042 | /* If the lower bound is less than the index type's minimum | |
2043 | value, truncate the range bounds. */ | |
b77aa1f7 AP |
2044 | if (TREE_CODE (min_value) == INTEGER_CST |
2045 | && tree_int_cst_compare (low, min_value) < 0) | |
eb172681 RS |
2046 | low = min_value; |
2047 | low = fold_convert (type, low); | |
2048 | ||
2049 | /* If the upper bound is greater than the index type's maximum | |
2050 | value, truncate the range bounds. */ | |
b77aa1f7 AP |
2051 | if (TREE_CODE (max_value) == INTEGER_CST |
2052 | && tree_int_cst_compare (high, max_value) > 0) | |
eb172681 RS |
2053 | high = max_value; |
2054 | high = fold_convert (type, high); | |
2055 | } | |
2056 | ||
56cb9733 | 2057 | |
b2ecb7a8 | 2058 | /* Add this label to the chain. Make sure to drop overflow flags. */ |
6ac1b3a4 | 2059 | r = (struct case_node *) pool_alloc (case_node_pool); |
b2ecb7a8 RG |
2060 | r->low = build_int_cst_wide (TREE_TYPE (low), TREE_INT_CST_LOW (low), |
2061 | TREE_INT_CST_HIGH (low)); | |
2062 | r->high = build_int_cst_wide (TREE_TYPE (high), TREE_INT_CST_LOW (high), | |
2063 | TREE_INT_CST_HIGH (high)); | |
57641239 | 2064 | r->code_label = label; |
a6c0a76c | 2065 | r->parent = r->left = NULL; |
7efcb746 PB |
2066 | r->right = head; |
2067 | return r; | |
28d81abb | 2068 | } |
28d81abb | 2069 | \f |
9bb231fd RS |
2070 | /* Maximum number of case bit tests. */ |
2071 | #define MAX_CASE_BIT_TESTS 3 | |
2072 | ||
2073 | /* By default, enable case bit tests on targets with ashlsi3. */ | |
2074 | #ifndef CASE_USE_BIT_TESTS | |
947131ba | 2075 | #define CASE_USE_BIT_TESTS (optab_handler (ashl_optab, word_mode) \ |
9bb231fd RS |
2076 | != CODE_FOR_nothing) |
2077 | #endif | |
2078 | ||
2079 | ||
2080 | /* A case_bit_test represents a set of case nodes that may be | |
2081 | selected from using a bit-wise comparison. HI and LO hold | |
2082 | the integer to be tested against, LABEL contains the label | |
2083 | to jump to upon success and BITS counts the number of case | |
2084 | nodes handled by this test, typically the number of bits | |
2085 | set in HI:LO. */ | |
2086 | ||
2087 | struct case_bit_test | |
2088 | { | |
2089 | HOST_WIDE_INT hi; | |
2090 | HOST_WIDE_INT lo; | |
2091 | rtx label; | |
2092 | int bits; | |
2093 | }; | |
2094 | ||
2095 | /* Determine whether "1 << x" is relatively cheap in word_mode. */ | |
2096 | ||
7e51717c AJ |
2097 | static |
2098 | bool lshift_cheap_p (void) | |
9bb231fd RS |
2099 | { |
2100 | static bool init = false; | |
2101 | static bool cheap = true; | |
2102 | ||
2103 | if (!init) | |
2104 | { | |
2105 | rtx reg = gen_rtx_REG (word_mode, 10000); | |
f40751dd JH |
2106 | int cost = rtx_cost (gen_rtx_ASHIFT (word_mode, const1_rtx, reg), SET, |
2107 | optimize_insn_for_speed_p ()); | |
9bb231fd RS |
2108 | cheap = cost < COSTS_N_INSNS (3); |
2109 | init = true; | |
2110 | } | |
2111 | ||
2112 | return cheap; | |
2113 | } | |
2114 | ||
2115 | /* Comparison function for qsort to order bit tests by decreasing | |
2116 | number of case nodes, i.e. the node with the most cases gets | |
2117 | tested first. */ | |
2118 | ||
f667741c SB |
2119 | static int |
2120 | case_bit_test_cmp (const void *p1, const void *p2) | |
9bb231fd | 2121 | { |
1634b18f KG |
2122 | const struct case_bit_test *const d1 = (const struct case_bit_test *) p1; |
2123 | const struct case_bit_test *const d2 = (const struct case_bit_test *) p2; | |
9bb231fd | 2124 | |
0174997a RS |
2125 | if (d2->bits != d1->bits) |
2126 | return d2->bits - d1->bits; | |
2127 | ||
2128 | /* Stabilize the sort. */ | |
2129 | return CODE_LABEL_NUMBER (d2->label) - CODE_LABEL_NUMBER (d1->label); | |
9bb231fd RS |
2130 | } |
2131 | ||
2132 | /* Expand a switch statement by a short sequence of bit-wise | |
2133 | comparisons. "switch(x)" is effectively converted into | |
2134 | "if ((1 << (x-MINVAL)) & CST)" where CST and MINVAL are | |
2135 | integer constants. | |
2136 | ||
2137 | INDEX_EXPR is the value being switched on, which is of | |
2138 | type INDEX_TYPE. MINVAL is the lowest case value of in | |
2139 | the case nodes, of INDEX_TYPE type, and RANGE is highest | |
2140 | value minus MINVAL, also of type INDEX_TYPE. NODES is | |
2141 | the set of case nodes, and DEFAULT_LABEL is the label to | |
2142 | branch to should none of the cases match. | |
2143 | ||
2144 | There *MUST* be MAX_CASE_BIT_TESTS or less unique case | |
2145 | node targets. */ | |
2146 | ||
2147 | static void | |
46c5ad27 AJ |
2148 | emit_case_bit_tests (tree index_type, tree index_expr, tree minval, |
2149 | tree range, case_node_ptr nodes, rtx default_label) | |
9bb231fd RS |
2150 | { |
2151 | struct case_bit_test test[MAX_CASE_BIT_TESTS]; | |
2152 | enum machine_mode mode; | |
2153 | rtx expr, index, label; | |
2154 | unsigned int i,j,lo,hi; | |
2155 | struct case_node *n; | |
2156 | unsigned int count; | |
2157 | ||
2158 | count = 0; | |
2159 | for (n = nodes; n; n = n->right) | |
2160 | { | |
2161 | label = label_rtx (n->code_label); | |
2162 | for (i = 0; i < count; i++) | |
7efcb746 | 2163 | if (label == test[i].label) |
9bb231fd RS |
2164 | break; |
2165 | ||
2166 | if (i == count) | |
2167 | { | |
41374e13 NS |
2168 | gcc_assert (count < MAX_CASE_BIT_TESTS); |
2169 | test[i].hi = 0; | |
2170 | test[i].lo = 0; | |
9bb231fd RS |
2171 | test[i].label = label; |
2172 | test[i].bits = 1; | |
2173 | count++; | |
2174 | } | |
2175 | else | |
2176 | test[i].bits++; | |
2177 | ||
4845b383 KH |
2178 | lo = tree_low_cst (fold_build2 (MINUS_EXPR, index_type, |
2179 | n->low, minval), 1); | |
2180 | hi = tree_low_cst (fold_build2 (MINUS_EXPR, index_type, | |
2181 | n->high, minval), 1); | |
9bb231fd RS |
2182 | for (j = lo; j <= hi; j++) |
2183 | if (j >= HOST_BITS_PER_WIDE_INT) | |
2184 | test[i].hi |= (HOST_WIDE_INT) 1 << (j - HOST_BITS_PER_INT); | |
2185 | else | |
2186 | test[i].lo |= (HOST_WIDE_INT) 1 << j; | |
2187 | } | |
2188 | ||
2189 | qsort (test, count, sizeof(*test), case_bit_test_cmp); | |
2190 | ||
4845b383 KH |
2191 | index_expr = fold_build2 (MINUS_EXPR, index_type, |
2192 | fold_convert (index_type, index_expr), | |
2193 | fold_convert (index_type, minval)); | |
84217346 | 2194 | index = expand_normal (index_expr); |
9bb231fd RS |
2195 | do_pending_stack_adjust (); |
2196 | ||
2197 | mode = TYPE_MODE (index_type); | |
84217346 | 2198 | expr = expand_normal (range); |
b7814a18 RG |
2199 | if (default_label) |
2200 | emit_cmp_and_jump_insns (index, expr, GTU, NULL_RTX, mode, 1, | |
2201 | default_label); | |
9bb231fd RS |
2202 | |
2203 | index = convert_to_mode (word_mode, index, 0); | |
2204 | index = expand_binop (word_mode, ashl_optab, const1_rtx, | |
2205 | index, NULL_RTX, 1, OPTAB_WIDEN); | |
2206 | ||
2207 | for (i = 0; i < count; i++) | |
2208 | { | |
2209 | expr = immed_double_const (test[i].lo, test[i].hi, word_mode); | |
2210 | expr = expand_binop (word_mode, and_optab, index, expr, | |
2211 | NULL_RTX, 1, OPTAB_WIDEN); | |
2212 | emit_cmp_and_jump_insns (expr, const0_rtx, NE, NULL_RTX, | |
2213 | word_mode, 1, test[i].label); | |
2214 | } | |
2215 | ||
b7814a18 RG |
2216 | if (default_label) |
2217 | emit_jump (default_label); | |
9bb231fd | 2218 | } |
ad82abb8 | 2219 | |
41cbdcd0 KH |
2220 | #ifndef HAVE_casesi |
2221 | #define HAVE_casesi 0 | |
2222 | #endif | |
2223 | ||
2224 | #ifndef HAVE_tablejump | |
2225 | #define HAVE_tablejump 0 | |
2226 | #endif | |
2227 | ||
3feaea00 | 2228 | /* Terminate a case (Pascal/Ada) or switch (C) statement |
9ab0ddd7 | 2229 | in which ORIG_INDEX is the expression to be tested. |
6f9fdf4d JJ |
2230 | If ORIG_TYPE is not NULL, it is the original ORIG_INDEX |
2231 | type as given in the source before any compiler conversions. | |
28d81abb RK |
2232 | Generate the code to test it and jump to the right place. */ |
2233 | ||
2234 | void | |
28ed065e | 2235 | expand_case (gimple stmt) |
28d81abb | 2236 | { |
9fb60a0d | 2237 | tree minval = NULL_TREE, maxval = NULL_TREE, range = NULL_TREE; |
28d81abb | 2238 | rtx default_label = 0; |
4cfa46c8 | 2239 | struct case_node *n; |
9bb231fd | 2240 | unsigned int count, uniq; |
28d81abb | 2241 | rtx index; |
ca695ac9 | 2242 | rtx table_label; |
28d81abb RK |
2243 | int ncases; |
2244 | rtx *labelvec; | |
a38e7aa5 | 2245 | int i; |
9bb231fd | 2246 | rtx before_case, end, lab; |
ca695ac9 | 2247 | |
28ed065e | 2248 | tree index_expr = gimple_switch_index (stmt); |
7efcb746 PB |
2249 | tree index_type = TREE_TYPE (index_expr); |
2250 | int unsignedp = TYPE_UNSIGNED (index_type); | |
2251 | ||
2252 | /* The insn after which the case dispatch should finally | |
2253 | be emitted. Zero for a dummy. */ | |
2254 | rtx start; | |
2255 | ||
2256 | /* A list of case labels; it is first built as a list and it may then | |
2257 | be rearranged into a nearly balanced binary tree. */ | |
2258 | struct case_node *case_list = 0; | |
2259 | ||
2260 | /* Label to jump to if no case matches. */ | |
b7814a18 | 2261 | tree default_label_decl = NULL_TREE; |
7efcb746 | 2262 | |
6ac1b3a4 LB |
2263 | alloc_pool case_node_pool = create_alloc_pool ("struct case_node pool", |
2264 | sizeof (struct case_node), | |
2265 | 100); | |
2266 | ||
28d81abb RK |
2267 | do_pending_stack_adjust (); |
2268 | ||
2269 | /* An ERROR_MARK occurs for various reasons including invalid data type. */ | |
1b0cb6fc | 2270 | if (index_type != error_mark_node) |
28d81abb | 2271 | { |
4e0148df | 2272 | tree elt; |
4cfa46c8 | 2273 | bitmap label_bitmap; |
28ed065e | 2274 | int stopi = 0; |
eb172681 | 2275 | |
5100d114 KH |
2276 | /* cleanup_tree_cfg removes all SWITCH_EXPR with their index |
2277 | expressions being INTEGER_CST. */ | |
2278 | gcc_assert (TREE_CODE (index_expr) != INTEGER_CST); | |
2279 | ||
28ed065e MM |
2280 | /* The default case, if ever taken, is the first element. */ |
2281 | elt = gimple_switch_label (stmt, 0); | |
b7814a18 RG |
2282 | if (!CASE_LOW (elt) && !CASE_HIGH (elt)) |
2283 | { | |
2284 | default_label_decl = CASE_LABEL (elt); | |
28ed065e | 2285 | stopi = 1; |
b7814a18 | 2286 | } |
4e0148df | 2287 | |
28ed065e | 2288 | for (i = gimple_switch_num_labels (stmt) - 1; i >= stopi; --i) |
4e0148df | 2289 | { |
3feaea00 | 2290 | tree low, high; |
28ed065e | 2291 | elt = gimple_switch_label (stmt, i); |
3feaea00 EB |
2292 | |
2293 | low = CASE_LOW (elt); | |
2294 | gcc_assert (low); | |
2295 | high = CASE_HIGH (elt); | |
2296 | ||
2297 | /* Discard empty ranges. */ | |
288bd0d7 | 2298 | if (high && tree_int_cst_lt (high, low)) |
3feaea00 EB |
2299 | continue; |
2300 | ||
2301 | case_list = add_case_node (case_list, index_type, low, high, | |
6ac1b3a4 | 2302 | CASE_LABEL (elt), case_node_pool); |
eb172681 RS |
2303 | } |
2304 | ||
2305 | ||
ede497cf | 2306 | before_case = start = get_last_insn (); |
b7814a18 RG |
2307 | if (default_label_decl) |
2308 | default_label = label_rtx (default_label_decl); | |
28d81abb | 2309 | |
5cfffc4e | 2310 | /* Get upper and lower bounds of case values. */ |
28d81abb | 2311 | |
9bb231fd | 2312 | uniq = 0; |
28d81abb | 2313 | count = 0; |
8bdbfff5 | 2314 | label_bitmap = BITMAP_ALLOC (NULL); |
7efcb746 | 2315 | for (n = case_list; n; n = n->right) |
28d81abb | 2316 | { |
28d81abb RK |
2317 | /* Count the elements and track the largest and smallest |
2318 | of them (treating them as signed even if they are not). */ | |
2319 | if (count++ == 0) | |
2320 | { | |
2321 | minval = n->low; | |
2322 | maxval = n->high; | |
2323 | } | |
2324 | else | |
2325 | { | |
288bd0d7 | 2326 | if (tree_int_cst_lt (n->low, minval)) |
28d81abb | 2327 | minval = n->low; |
288bd0d7 | 2328 | if (tree_int_cst_lt (maxval, n->high)) |
28d81abb RK |
2329 | maxval = n->high; |
2330 | } | |
2331 | /* A range counts double, since it requires two compares. */ | |
2332 | if (! tree_int_cst_equal (n->low, n->high)) | |
2333 | count++; | |
9bb231fd | 2334 | |
4cfa46c8 JL |
2335 | /* If we have not seen this label yet, then increase the |
2336 | number of unique case node targets seen. */ | |
9bb231fd | 2337 | lab = label_rtx (n->code_label); |
4cfa46c8 JL |
2338 | if (!bitmap_bit_p (label_bitmap, CODE_LABEL_NUMBER (lab))) |
2339 | { | |
2340 | bitmap_set_bit (label_bitmap, CODE_LABEL_NUMBER (lab)); | |
2341 | uniq++; | |
2342 | } | |
28d81abb RK |
2343 | } |
2344 | ||
8bdbfff5 | 2345 | BITMAP_FREE (label_bitmap); |
4cfa46c8 | 2346 | |
5372d088 | 2347 | /* cleanup_tree_cfg removes all SWITCH_EXPR with a single |
2aabee29 AO |
2348 | destination, such as one with a default case only. However, |
2349 | it doesn't remove cases that are out of range for the switch | |
2350 | type, so we may still get a zero here. */ | |
2351 | if (count == 0) | |
2352 | { | |
b7814a18 RG |
2353 | if (default_label) |
2354 | emit_jump (default_label); | |
6ac1b3a4 | 2355 | free_alloc_pool (case_node_pool); |
2aabee29 AO |
2356 | return; |
2357 | } | |
28d81abb | 2358 | |
5372d088 | 2359 | /* Compute span of values. */ |
4845b383 | 2360 | range = fold_build2 (MINUS_EXPR, index_type, maxval, minval); |
3474db0e | 2361 | |
9bb231fd RS |
2362 | /* Try implementing this switch statement by a short sequence of |
2363 | bit-wise comparisons. However, we let the binary-tree case | |
2364 | below handle constant index expressions. */ | |
5372d088 KH |
2365 | if (CASE_USE_BIT_TESTS |
2366 | && ! TREE_CONSTANT (index_expr) | |
2367 | && compare_tree_int (range, GET_MODE_BITSIZE (word_mode)) < 0 | |
2368 | && compare_tree_int (range, 0) > 0 | |
2369 | && lshift_cheap_p () | |
2370 | && ((uniq == 1 && count >= 3) | |
2371 | || (uniq == 2 && count >= 5) | |
2372 | || (uniq == 3 && count >= 6))) | |
9bb231fd RS |
2373 | { |
2374 | /* Optimize the case where all the case values fit in a | |
2375 | word without having to subtract MINVAL. In this case, | |
2376 | we can optimize away the subtraction. */ | |
2377 | if (compare_tree_int (minval, 0) > 0 | |
2378 | && compare_tree_int (maxval, GET_MODE_BITSIZE (word_mode)) < 0) | |
2379 | { | |
3bedcc89 | 2380 | minval = build_int_cst (index_type, 0); |
9bb231fd RS |
2381 | range = maxval; |
2382 | } | |
2383 | emit_case_bit_tests (index_type, index_expr, minval, range, | |
7efcb746 | 2384 | case_list, default_label); |
9bb231fd RS |
2385 | } |
2386 | ||
28d81abb RK |
2387 | /* If range of values is much bigger than number of values, |
2388 | make a sequence of conditional branches instead of a dispatch. | |
2389 | If the switch-index is a constant, do it this way | |
2390 | because we can optimize it. */ | |
4f73c5dd | 2391 | |
e6ff3083 | 2392 | else if (count < targetm.case_values_threshold () |
9e4b13a7 | 2393 | || compare_tree_int (range, |
efd8f750 | 2394 | (optimize_insn_for_size_p () ? 3 : 10) * count) > 0 |
f0c988c8 BS |
2395 | /* RANGE may be signed, and really large ranges will show up |
2396 | as negative numbers. */ | |
2397 | || compare_tree_int (range, 0) < 0 | |
3f6fe18e RK |
2398 | #ifndef ASM_OUTPUT_ADDR_DIFF_ELT |
2399 | || flag_pic | |
2400 | #endif | |
82c0180d | 2401 | || !flag_jump_tables |
41cbdcd0 KH |
2402 | || TREE_CONSTANT (index_expr) |
2403 | /* If neither casesi or tablejump is available, we can | |
2404 | only go this way. */ | |
2405 | || (!HAVE_casesi && !HAVE_tablejump)) | |
28d81abb | 2406 | { |
84217346 | 2407 | index = expand_normal (index_expr); |
28d81abb RK |
2408 | |
2409 | /* If the index is a short or char that we do not have | |
2410 | an insn to handle comparisons directly, convert it to | |
2411 | a full integer now, rather than letting each comparison | |
2412 | generate the conversion. */ | |
2413 | ||
2414 | if (GET_MODE_CLASS (GET_MODE (index)) == MODE_INT | |
ef89d648 | 2415 | && ! have_insn_for (COMPARE, GET_MODE (index))) |
28d81abb RK |
2416 | { |
2417 | enum machine_mode wider_mode; | |
2418 | for (wider_mode = GET_MODE (index); wider_mode != VOIDmode; | |
2419 | wider_mode = GET_MODE_WIDER_MODE (wider_mode)) | |
ef89d648 | 2420 | if (have_insn_for (COMPARE, wider_mode)) |
28d81abb RK |
2421 | { |
2422 | index = convert_to_mode (wider_mode, index, unsignedp); | |
2423 | break; | |
2424 | } | |
2425 | } | |
2426 | ||
28d81abb RK |
2427 | do_pending_stack_adjust (); |
2428 | ||
3c0cb5de | 2429 | if (MEM_P (index)) |
28d81abb | 2430 | index = copy_to_reg (index); |
28d81abb | 2431 | |
b2c5a1e9 KH |
2432 | /* We generate a binary decision tree to select the |
2433 | appropriate target code. This is done as follows: | |
5100d114 KH |
2434 | |
2435 | The list of cases is rearranged into a binary tree, | |
2436 | nearly optimal assuming equal probability for each case. | |
2437 | ||
2438 | The tree is transformed into RTL, eliminating | |
2439 | redundant test conditions at the same time. | |
2440 | ||
2441 | If program flow could reach the end of the | |
2442 | decision tree an unconditional jump to the | |
2443 | default code is emitted. */ | |
2444 | ||
28ed065e | 2445 | use_cost_table = estimate_case_costs (case_list); |
5100d114 KH |
2446 | balance_case_nodes (&case_list, NULL); |
2447 | emit_case_nodes (index, case_list, default_label, index_type); | |
b7814a18 RG |
2448 | if (default_label) |
2449 | emit_jump (default_label); | |
28d81abb RK |
2450 | } |
2451 | else | |
2452 | { | |
55187c8a | 2453 | rtx fallback_label = label_rtx (case_list->code_label); |
100e3acb | 2454 | table_label = gen_label_rtx (); |
ad82abb8 | 2455 | if (! try_casesi (index_type, index_expr, minval, range, |
55187c8a | 2456 | table_label, default_label, fallback_label)) |
28d81abb | 2457 | { |
41374e13 | 2458 | bool ok; |
1ff37128 | 2459 | |
786de7eb | 2460 | /* Index jumptables from zero for suitable values of |
1ff37128 | 2461 | minval to avoid a subtraction. */ |
efd8f750 | 2462 | if (optimize_insn_for_speed_p () |
786de7eb KH |
2463 | && compare_tree_int (minval, 0) > 0 |
2464 | && compare_tree_int (minval, 3) < 0) | |
2465 | { | |
3bedcc89 | 2466 | minval = build_int_cst (index_type, 0); |
786de7eb KH |
2467 | range = maxval; |
2468 | } | |
1ff37128 | 2469 | |
41374e13 NS |
2470 | ok = try_tablejump (index_type, index_expr, minval, range, |
2471 | table_label, default_label); | |
2472 | gcc_assert (ok); | |
28d81abb | 2473 | } |
786de7eb | 2474 | |
28d81abb RK |
2475 | /* Get table of labels to jump to, in order of case index. */ |
2476 | ||
1ff37128 | 2477 | ncases = tree_low_cst (range, 0) + 1; |
1634b18f | 2478 | labelvec = XALLOCAVEC (rtx, ncases); |
703ad42b | 2479 | memset (labelvec, 0, ncases * sizeof (rtx)); |
28d81abb | 2480 | |
7efcb746 | 2481 | for (n = case_list; n; n = n->right) |
28d81abb | 2482 | { |
2d9d49e4 OH |
2483 | /* Compute the low and high bounds relative to the minimum |
2484 | value since that should fit in a HOST_WIDE_INT while the | |
2485 | actual values may not. */ | |
2486 | HOST_WIDE_INT i_low | |
4845b383 KH |
2487 | = tree_low_cst (fold_build2 (MINUS_EXPR, index_type, |
2488 | n->low, minval), 1); | |
2d9d49e4 | 2489 | HOST_WIDE_INT i_high |
4845b383 KH |
2490 | = tree_low_cst (fold_build2 (MINUS_EXPR, index_type, |
2491 | n->high, minval), 1); | |
2d9d49e4 OH |
2492 | HOST_WIDE_INT i; |
2493 | ||
2494 | for (i = i_low; i <= i_high; i ++) | |
2495 | labelvec[i] | |
2496 | = gen_rtx_LABEL_REF (Pmode, label_rtx (n->code_label)); | |
28d81abb RK |
2497 | } |
2498 | ||
55187c8a RG |
2499 | /* Fill in the gaps with the default. We may have gaps at |
2500 | the beginning if we tried to avoid the minval subtraction, | |
2501 | so substitute some label even if the default label was | |
2502 | deemed unreachable. */ | |
2503 | if (!default_label) | |
2504 | default_label = fallback_label; | |
2505 | for (i = 0; i < ncases; i++) | |
2506 | if (labelvec[i] == 0) | |
2507 | labelvec[i] = gen_rtx_LABEL_REF (Pmode, default_label); | |
28d81abb | 2508 | |
f9da5064 | 2509 | /* Output the table. */ |
28d81abb RK |
2510 | emit_label (table_label); |
2511 | ||
18543a22 | 2512 | if (CASE_VECTOR_PC_RELATIVE || flag_pic) |
38a448ca RH |
2513 | emit_jump_insn (gen_rtx_ADDR_DIFF_VEC (CASE_VECTOR_MODE, |
2514 | gen_rtx_LABEL_REF (Pmode, table_label), | |
33f7f353 | 2515 | gen_rtvec_v (ncases, labelvec), |
4381f7c2 | 2516 | const0_rtx, const0_rtx)); |
28d81abb | 2517 | else |
38a448ca RH |
2518 | emit_jump_insn (gen_rtx_ADDR_VEC (CASE_VECTOR_MODE, |
2519 | gen_rtvec_v (ncases, labelvec))); | |
28d81abb | 2520 | |
6be85b25 | 2521 | /* Record no drop-through after the table. */ |
28d81abb | 2522 | emit_barrier (); |
28d81abb RK |
2523 | } |
2524 | ||
2270623a JM |
2525 | before_case = NEXT_INSN (before_case); |
2526 | end = get_last_insn (); | |
7efcb746 | 2527 | reorder_insns (before_case, end, start); |
28d81abb | 2528 | } |
1b0cb6fc | 2529 | |
28d81abb | 2530 | free_temp_slots (); |
6ac1b3a4 | 2531 | free_alloc_pool (case_node_pool); |
28d81abb RK |
2532 | } |
2533 | ||
feb04780 | 2534 | /* Generate code to jump to LABEL if OP0 and OP1 are equal in mode MODE. */ |
28d81abb RK |
2535 | |
2536 | static void | |
feb04780 RS |
2537 | do_jump_if_equal (enum machine_mode mode, rtx op0, rtx op1, rtx label, |
2538 | int unsignedp) | |
28d81abb | 2539 | { |
feb04780 | 2540 | do_compare_rtx_and_jump (op0, op1, EQ, unsignedp, mode, |
40e90eac | 2541 | NULL_RTX, NULL_RTX, label, -1); |
28d81abb RK |
2542 | } |
2543 | \f | |
2544 | /* Not all case values are encountered equally. This function | |
2545 | uses a heuristic to weight case labels, in cases where that | |
2546 | looks like a reasonable thing to do. | |
2547 | ||
2548 | Right now, all we try to guess is text, and we establish the | |
2549 | following weights: | |
2550 | ||
2551 | chars above space: 16 | |
2552 | digits: 16 | |
2553 | default: 12 | |
2554 | space, punct: 8 | |
2555 | tab: 4 | |
2556 | newline: 2 | |
2557 | other "\" chars: 1 | |
2558 | remaining chars: 0 | |
2559 | ||
2560 | If we find any cases in the switch that are not either -1 or in the range | |
2561 | of valid ASCII characters, or are control characters other than those | |
2562 | commonly used with "\", don't treat this switch scanning text. | |
2563 | ||
2564 | Return 1 if these nodes are suitable for cost estimation, otherwise | |
2565 | return 0. */ | |
2566 | ||
2567 | static int | |
46c5ad27 | 2568 | estimate_case_costs (case_node_ptr node) |
28d81abb | 2569 | { |
f2d1f0ba | 2570 | tree min_ascii = integer_minus_one_node; |
aeba6c28 | 2571 | tree max_ascii = build_int_cst (TREE_TYPE (node->high), 127); |
28d81abb RK |
2572 | case_node_ptr n; |
2573 | int i; | |
2574 | ||
2575 | /* If we haven't already made the cost table, make it now. Note that the | |
2576 | lower bound of the table is -1, not zero. */ | |
2577 | ||
2a2137c4 | 2578 | if (! cost_table_initialized) |
28d81abb | 2579 | { |
2a2137c4 | 2580 | cost_table_initialized = 1; |
28d81abb RK |
2581 | |
2582 | for (i = 0; i < 128; i++) | |
2583 | { | |
e9a780ec | 2584 | if (ISALNUM (i)) |
2a2137c4 | 2585 | COST_TABLE (i) = 16; |
e9a780ec | 2586 | else if (ISPUNCT (i)) |
2a2137c4 | 2587 | COST_TABLE (i) = 8; |
e9a780ec | 2588 | else if (ISCNTRL (i)) |
2a2137c4 | 2589 | COST_TABLE (i) = -1; |
28d81abb RK |
2590 | } |
2591 | ||
2a2137c4 RH |
2592 | COST_TABLE (' ') = 8; |
2593 | COST_TABLE ('\t') = 4; | |
2594 | COST_TABLE ('\0') = 4; | |
2595 | COST_TABLE ('\n') = 2; | |
2596 | COST_TABLE ('\f') = 1; | |
2597 | COST_TABLE ('\v') = 1; | |
2598 | COST_TABLE ('\b') = 1; | |
28d81abb RK |
2599 | } |
2600 | ||
2601 | /* See if all the case expressions look like text. It is text if the | |
2602 | constant is >= -1 and the highest constant is <= 127. Do all comparisons | |
2603 | as signed arithmetic since we don't want to ever access cost_table with a | |
2604 | value less than -1. Also check that none of the constants in a range | |
2605 | are strange control characters. */ | |
2606 | ||
2607 | for (n = node; n; n = n->right) | |
2608 | { | |
288bd0d7 RG |
2609 | if (tree_int_cst_lt (n->low, min_ascii) |
2610 | || tree_int_cst_lt (max_ascii, n->high)) | |
28d81abb RK |
2611 | return 0; |
2612 | ||
05bccae2 RK |
2613 | for (i = (HOST_WIDE_INT) TREE_INT_CST_LOW (n->low); |
2614 | i <= (HOST_WIDE_INT) TREE_INT_CST_LOW (n->high); i++) | |
2a2137c4 | 2615 | if (COST_TABLE (i) < 0) |
28d81abb RK |
2616 | return 0; |
2617 | } | |
2618 | ||
2619 | /* All interesting values are within the range of interesting | |
2620 | ASCII characters. */ | |
2621 | return 1; | |
2622 | } | |
2623 | ||
28d81abb RK |
2624 | /* Take an ordered list of case nodes |
2625 | and transform them into a near optimal binary tree, | |
6dc42e49 | 2626 | on the assumption that any target code selection value is as |
28d81abb RK |
2627 | likely as any other. |
2628 | ||
2629 | The transformation is performed by splitting the ordered | |
2630 | list into two equal sections plus a pivot. The parts are | |
2631 | then attached to the pivot as left and right branches. Each | |
38e01259 | 2632 | branch is then transformed recursively. */ |
28d81abb RK |
2633 | |
2634 | static void | |
46c5ad27 | 2635 | balance_case_nodes (case_node_ptr *head, case_node_ptr parent) |
28d81abb | 2636 | { |
b3694847 | 2637 | case_node_ptr np; |
28d81abb RK |
2638 | |
2639 | np = *head; | |
2640 | if (np) | |
2641 | { | |
2642 | int cost = 0; | |
2643 | int i = 0; | |
2644 | int ranges = 0; | |
b3694847 | 2645 | case_node_ptr *npp; |
28d81abb RK |
2646 | case_node_ptr left; |
2647 | ||
2648 | /* Count the number of entries on branch. Also count the ranges. */ | |
2649 | ||
2650 | while (np) | |
2651 | { | |
2652 | if (!tree_int_cst_equal (np->low, np->high)) | |
2653 | { | |
2654 | ranges++; | |
2655 | if (use_cost_table) | |
2a2137c4 | 2656 | cost += COST_TABLE (TREE_INT_CST_LOW (np->high)); |
28d81abb RK |
2657 | } |
2658 | ||
2659 | if (use_cost_table) | |
2a2137c4 | 2660 | cost += COST_TABLE (TREE_INT_CST_LOW (np->low)); |
28d81abb RK |
2661 | |
2662 | i++; | |
2663 | np = np->right; | |
2664 | } | |
2665 | ||
2666 | if (i > 2) | |
2667 | { | |
2668 | /* Split this list if it is long enough for that to help. */ | |
2669 | npp = head; | |
2670 | left = *npp; | |
2671 | if (use_cost_table) | |
2672 | { | |
2673 | /* Find the place in the list that bisects the list's total cost, | |
2674 | Here I gets half the total cost. */ | |
2675 | int n_moved = 0; | |
2676 | i = (cost + 1) / 2; | |
2677 | while (1) | |
2678 | { | |
2679 | /* Skip nodes while their cost does not reach that amount. */ | |
2680 | if (!tree_int_cst_equal ((*npp)->low, (*npp)->high)) | |
2a2137c4 RH |
2681 | i -= COST_TABLE (TREE_INT_CST_LOW ((*npp)->high)); |
2682 | i -= COST_TABLE (TREE_INT_CST_LOW ((*npp)->low)); | |
28d81abb RK |
2683 | if (i <= 0) |
2684 | break; | |
2685 | npp = &(*npp)->right; | |
2686 | n_moved += 1; | |
2687 | } | |
2688 | if (n_moved == 0) | |
2689 | { | |
2690 | /* Leave this branch lopsided, but optimize left-hand | |
2691 | side and fill in `parent' fields for right-hand side. */ | |
2692 | np = *head; | |
2693 | np->parent = parent; | |
2694 | balance_case_nodes (&np->left, np); | |
2695 | for (; np->right; np = np->right) | |
2696 | np->right->parent = np; | |
2697 | return; | |
2698 | } | |
2699 | } | |
2700 | /* If there are just three nodes, split at the middle one. */ | |
2701 | else if (i == 3) | |
2702 | npp = &(*npp)->right; | |
2703 | else | |
2704 | { | |
2705 | /* Find the place in the list that bisects the list's total cost, | |
2706 | where ranges count as 2. | |
2707 | Here I gets half the total cost. */ | |
2708 | i = (i + ranges + 1) / 2; | |
2709 | while (1) | |
2710 | { | |
2711 | /* Skip nodes while their cost does not reach that amount. */ | |
2712 | if (!tree_int_cst_equal ((*npp)->low, (*npp)->high)) | |
2713 | i--; | |
2714 | i--; | |
2715 | if (i <= 0) | |
2716 | break; | |
2717 | npp = &(*npp)->right; | |
2718 | } | |
2719 | } | |
2720 | *head = np = *npp; | |
2721 | *npp = 0; | |
2722 | np->parent = parent; | |
2723 | np->left = left; | |
2724 | ||
2725 | /* Optimize each of the two split parts. */ | |
2726 | balance_case_nodes (&np->left, np); | |
2727 | balance_case_nodes (&np->right, np); | |
2728 | } | |
2729 | else | |
2730 | { | |
2731 | /* Else leave this branch as one level, | |
2732 | but fill in `parent' fields. */ | |
2733 | np = *head; | |
2734 | np->parent = parent; | |
2735 | for (; np->right; np = np->right) | |
2736 | np->right->parent = np; | |
2737 | } | |
2738 | } | |
2739 | } | |
2740 | \f | |
2741 | /* Search the parent sections of the case node tree | |
2742 | to see if a test for the lower bound of NODE would be redundant. | |
2743 | INDEX_TYPE is the type of the index expression. | |
2744 | ||
2745 | The instructions to generate the case decision tree are | |
2746 | output in the same order as nodes are processed so it is | |
2747 | known that if a parent node checks the range of the current | |
2748 | node minus one that the current node is bounded at its lower | |
2749 | span. Thus the test would be redundant. */ | |
2750 | ||
2751 | static int | |
46c5ad27 | 2752 | node_has_low_bound (case_node_ptr node, tree index_type) |
28d81abb RK |
2753 | { |
2754 | tree low_minus_one; | |
2755 | case_node_ptr pnode; | |
2756 | ||
2757 | /* If the lower bound of this node is the lowest value in the index type, | |
2758 | we need not test it. */ | |
2759 | ||
2760 | if (tree_int_cst_equal (node->low, TYPE_MIN_VALUE (index_type))) | |
2761 | return 1; | |
2762 | ||
2763 | /* If this node has a left branch, the value at the left must be less | |
2764 | than that at this node, so it cannot be bounded at the bottom and | |
2765 | we need not bother testing any further. */ | |
2766 | ||
2767 | if (node->left) | |
2768 | return 0; | |
2769 | ||
4845b383 | 2770 | low_minus_one = fold_build2 (MINUS_EXPR, TREE_TYPE (node->low), |
3bedcc89 RG |
2771 | node->low, |
2772 | build_int_cst (TREE_TYPE (node->low), 1)); | |
28d81abb RK |
2773 | |
2774 | /* If the subtraction above overflowed, we can't verify anything. | |
2775 | Otherwise, look for a parent that tests our value - 1. */ | |
2776 | ||
2777 | if (! tree_int_cst_lt (low_minus_one, node->low)) | |
2778 | return 0; | |
2779 | ||
2780 | for (pnode = node->parent; pnode; pnode = pnode->parent) | |
2781 | if (tree_int_cst_equal (low_minus_one, pnode->high)) | |
2782 | return 1; | |
2783 | ||
2784 | return 0; | |
2785 | } | |
2786 | ||
2787 | /* Search the parent sections of the case node tree | |
2788 | to see if a test for the upper bound of NODE would be redundant. | |
2789 | INDEX_TYPE is the type of the index expression. | |
2790 | ||
2791 | The instructions to generate the case decision tree are | |
2792 | output in the same order as nodes are processed so it is | |
2793 | known that if a parent node checks the range of the current | |
2794 | node plus one that the current node is bounded at its upper | |
2795 | span. Thus the test would be redundant. */ | |
2796 | ||
2797 | static int | |
46c5ad27 | 2798 | node_has_high_bound (case_node_ptr node, tree index_type) |
28d81abb RK |
2799 | { |
2800 | tree high_plus_one; | |
2801 | case_node_ptr pnode; | |
2802 | ||
e1ee5cdc RH |
2803 | /* If there is no upper bound, obviously no test is needed. */ |
2804 | ||
2805 | if (TYPE_MAX_VALUE (index_type) == NULL) | |
2806 | return 1; | |
2807 | ||
28d81abb RK |
2808 | /* If the upper bound of this node is the highest value in the type |
2809 | of the index expression, we need not test against it. */ | |
2810 | ||
2811 | if (tree_int_cst_equal (node->high, TYPE_MAX_VALUE (index_type))) | |
2812 | return 1; | |
2813 | ||
2814 | /* If this node has a right branch, the value at the right must be greater | |
2815 | than that at this node, so it cannot be bounded at the top and | |
2816 | we need not bother testing any further. */ | |
2817 | ||
2818 | if (node->right) | |
2819 | return 0; | |
2820 | ||
4845b383 | 2821 | high_plus_one = fold_build2 (PLUS_EXPR, TREE_TYPE (node->high), |
3bedcc89 RG |
2822 | node->high, |
2823 | build_int_cst (TREE_TYPE (node->high), 1)); | |
28d81abb RK |
2824 | |
2825 | /* If the addition above overflowed, we can't verify anything. | |
2826 | Otherwise, look for a parent that tests our value + 1. */ | |
2827 | ||
2828 | if (! tree_int_cst_lt (node->high, high_plus_one)) | |
2829 | return 0; | |
2830 | ||
2831 | for (pnode = node->parent; pnode; pnode = pnode->parent) | |
2832 | if (tree_int_cst_equal (high_plus_one, pnode->low)) | |
2833 | return 1; | |
2834 | ||
2835 | return 0; | |
2836 | } | |
2837 | ||
2838 | /* Search the parent sections of the | |
2839 | case node tree to see if both tests for the upper and lower | |
2840 | bounds of NODE would be redundant. */ | |
2841 | ||
2842 | static int | |
46c5ad27 | 2843 | node_is_bounded (case_node_ptr node, tree index_type) |
28d81abb RK |
2844 | { |
2845 | return (node_has_low_bound (node, index_type) | |
2846 | && node_has_high_bound (node, index_type)); | |
2847 | } | |
28d81abb RK |
2848 | \f |
2849 | /* Emit step-by-step code to select a case for the value of INDEX. | |
2850 | The thus generated decision tree follows the form of the | |
2851 | case-node binary tree NODE, whose nodes represent test conditions. | |
2852 | INDEX_TYPE is the type of the index of the switch. | |
2853 | ||
2854 | Care is taken to prune redundant tests from the decision tree | |
2855 | by detecting any boundary conditions already checked by | |
2856 | emitted rtx. (See node_has_high_bound, node_has_low_bound | |
2857 | and node_is_bounded, above.) | |
2858 | ||
2859 | Where the test conditions can be shown to be redundant we emit | |
2860 | an unconditional jump to the target code. As a further | |
2861 | optimization, the subordinates of a tree node are examined to | |
2862 | check for bounded nodes. In this case conditional and/or | |
2863 | unconditional jumps as a result of the boundary check for the | |
2864 | current node are arranged to target the subordinates associated | |
38e01259 | 2865 | code for out of bound conditions on the current node. |
28d81abb | 2866 | |
f72aed24 | 2867 | We can assume that when control reaches the code generated here, |
28d81abb RK |
2868 | the index value has already been compared with the parents |
2869 | of this node, and determined to be on the same side of each parent | |
2870 | as this node is. Thus, if this node tests for the value 51, | |
2871 | and a parent tested for 52, we don't need to consider | |
2872 | the possibility of a value greater than 51. If another parent | |
2873 | tests for the value 50, then this node need not test anything. */ | |
2874 | ||
2875 | static void | |
46c5ad27 AJ |
2876 | emit_case_nodes (rtx index, case_node_ptr node, rtx default_label, |
2877 | tree index_type) | |
28d81abb RK |
2878 | { |
2879 | /* If INDEX has an unsigned type, we must make unsigned branches. */ | |
8df83eae | 2880 | int unsignedp = TYPE_UNSIGNED (index_type); |
28d81abb | 2881 | enum machine_mode mode = GET_MODE (index); |
69107307 | 2882 | enum machine_mode imode = TYPE_MODE (index_type); |
28d81abb | 2883 | |
f8318079 RS |
2884 | /* Handle indices detected as constant during RTL expansion. */ |
2885 | if (mode == VOIDmode) | |
2886 | mode = imode; | |
2887 | ||
28d81abb RK |
2888 | /* See if our parents have already tested everything for us. |
2889 | If they have, emit an unconditional jump for this node. */ | |
2890 | if (node_is_bounded (node, index_type)) | |
2891 | emit_jump (label_rtx (node->code_label)); | |
2892 | ||
2893 | else if (tree_int_cst_equal (node->low, node->high)) | |
2894 | { | |
2895 | /* Node is single valued. First see if the index expression matches | |
0f41302f | 2896 | this node and then check our children, if any. */ |
28d81abb | 2897 | |
feb04780 | 2898 | do_jump_if_equal (mode, index, |
69107307 | 2899 | convert_modes (mode, imode, |
84217346 | 2900 | expand_normal (node->low), |
69107307 | 2901 | unsignedp), |
28d81abb RK |
2902 | label_rtx (node->code_label), unsignedp); |
2903 | ||
2904 | if (node->right != 0 && node->left != 0) | |
2905 | { | |
2906 | /* This node has children on both sides. | |
2907 | Dispatch to one side or the other | |
2908 | by comparing the index value with this node's value. | |
2909 | If one subtree is bounded, check that one first, | |
2910 | so we can avoid real branches in the tree. */ | |
2911 | ||
2912 | if (node_is_bounded (node->right, index_type)) | |
2913 | { | |
4381f7c2 | 2914 | emit_cmp_and_jump_insns (index, |
69107307 AO |
2915 | convert_modes |
2916 | (mode, imode, | |
84217346 | 2917 | expand_normal (node->high), |
69107307 | 2918 | unsignedp), |
d43e0b7d | 2919 | GT, NULL_RTX, mode, unsignedp, |
4381f7c2 | 2920 | label_rtx (node->right->code_label)); |
28d81abb RK |
2921 | emit_case_nodes (index, node->left, default_label, index_type); |
2922 | } | |
2923 | ||
2924 | else if (node_is_bounded (node->left, index_type)) | |
2925 | { | |
4381f7c2 | 2926 | emit_cmp_and_jump_insns (index, |
69107307 AO |
2927 | convert_modes |
2928 | (mode, imode, | |
84217346 | 2929 | expand_normal (node->high), |
69107307 | 2930 | unsignedp), |
d43e0b7d | 2931 | LT, NULL_RTX, mode, unsignedp, |
c5d5d461 | 2932 | label_rtx (node->left->code_label)); |
28d81abb RK |
2933 | emit_case_nodes (index, node->right, default_label, index_type); |
2934 | } | |
2935 | ||
43a21dfc KH |
2936 | /* If both children are single-valued cases with no |
2937 | children, finish up all the work. This way, we can save | |
2938 | one ordered comparison. */ | |
2939 | else if (tree_int_cst_equal (node->right->low, node->right->high) | |
2940 | && node->right->left == 0 | |
2941 | && node->right->right == 0 | |
2942 | && tree_int_cst_equal (node->left->low, node->left->high) | |
2943 | && node->left->left == 0 | |
2944 | && node->left->right == 0) | |
2945 | { | |
2946 | /* Neither node is bounded. First distinguish the two sides; | |
2947 | then emit the code for one side at a time. */ | |
2948 | ||
2949 | /* See if the value matches what the right hand side | |
2950 | wants. */ | |
feb04780 | 2951 | do_jump_if_equal (mode, index, |
43a21dfc | 2952 | convert_modes (mode, imode, |
84217346 | 2953 | expand_normal (node->right->low), |
43a21dfc KH |
2954 | unsignedp), |
2955 | label_rtx (node->right->code_label), | |
2956 | unsignedp); | |
2957 | ||
2958 | /* See if the value matches what the left hand side | |
2959 | wants. */ | |
feb04780 | 2960 | do_jump_if_equal (mode, index, |
43a21dfc | 2961 | convert_modes (mode, imode, |
84217346 | 2962 | expand_normal (node->left->low), |
43a21dfc KH |
2963 | unsignedp), |
2964 | label_rtx (node->left->code_label), | |
2965 | unsignedp); | |
2966 | } | |
2967 | ||
28d81abb RK |
2968 | else |
2969 | { | |
2970 | /* Neither node is bounded. First distinguish the two sides; | |
2971 | then emit the code for one side at a time. */ | |
2972 | ||
c2255bc4 AH |
2973 | tree test_label |
2974 | = build_decl (CURR_INSN_LOCATION, | |
2975 | LABEL_DECL, NULL_TREE, NULL_TREE); | |
28d81abb RK |
2976 | |
2977 | /* See if the value is on the right. */ | |
4381f7c2 | 2978 | emit_cmp_and_jump_insns (index, |
69107307 AO |
2979 | convert_modes |
2980 | (mode, imode, | |
84217346 | 2981 | expand_normal (node->high), |
69107307 | 2982 | unsignedp), |
d43e0b7d | 2983 | GT, NULL_RTX, mode, unsignedp, |
c5d5d461 | 2984 | label_rtx (test_label)); |
28d81abb RK |
2985 | |
2986 | /* Value must be on the left. | |
2987 | Handle the left-hand subtree. */ | |
2988 | emit_case_nodes (index, node->left, default_label, index_type); | |
2989 | /* If left-hand subtree does nothing, | |
2990 | go to default. */ | |
b7814a18 RG |
2991 | if (default_label) |
2992 | emit_jump (default_label); | |
28d81abb RK |
2993 | |
2994 | /* Code branches here for the right-hand subtree. */ | |
2995 | expand_label (test_label); | |
2996 | emit_case_nodes (index, node->right, default_label, index_type); | |
2997 | } | |
2998 | } | |
2999 | ||
3000 | else if (node->right != 0 && node->left == 0) | |
3001 | { | |
adb35797 | 3002 | /* Here we have a right child but no left so we issue a conditional |
28d81abb RK |
3003 | branch to default and process the right child. |
3004 | ||
adb35797 KH |
3005 | Omit the conditional branch to default if the right child |
3006 | does not have any children and is single valued; it would | |
3007 | cost too much space to save so little time. */ | |
28d81abb | 3008 | |
de14fd73 | 3009 | if (node->right->right || node->right->left |
28d81abb RK |
3010 | || !tree_int_cst_equal (node->right->low, node->right->high)) |
3011 | { | |
3012 | if (!node_has_low_bound (node, index_type)) | |
3013 | { | |
4381f7c2 | 3014 | emit_cmp_and_jump_insns (index, |
69107307 AO |
3015 | convert_modes |
3016 | (mode, imode, | |
84217346 | 3017 | expand_normal (node->high), |
69107307 | 3018 | unsignedp), |
d43e0b7d | 3019 | LT, NULL_RTX, mode, unsignedp, |
c5d5d461 | 3020 | default_label); |
28d81abb RK |
3021 | } |
3022 | ||
3023 | emit_case_nodes (index, node->right, default_label, index_type); | |
3024 | } | |
3025 | else | |
3026 | /* We cannot process node->right normally | |
3027 | since we haven't ruled out the numbers less than | |
3028 | this node's value. So handle node->right explicitly. */ | |
feb04780 | 3029 | do_jump_if_equal (mode, index, |
69107307 AO |
3030 | convert_modes |
3031 | (mode, imode, | |
84217346 | 3032 | expand_normal (node->right->low), |
69107307 | 3033 | unsignedp), |
28d81abb RK |
3034 | label_rtx (node->right->code_label), unsignedp); |
3035 | } | |
3036 | ||
3037 | else if (node->right == 0 && node->left != 0) | |
3038 | { | |
3039 | /* Just one subtree, on the left. */ | |
4381f7c2 | 3040 | if (node->left->left || node->left->right |
28d81abb RK |
3041 | || !tree_int_cst_equal (node->left->low, node->left->high)) |
3042 | { | |
3043 | if (!node_has_high_bound (node, index_type)) | |
3044 | { | |
69107307 AO |
3045 | emit_cmp_and_jump_insns (index, |
3046 | convert_modes | |
3047 | (mode, imode, | |
84217346 | 3048 | expand_normal (node->high), |
69107307 | 3049 | unsignedp), |
d43e0b7d | 3050 | GT, NULL_RTX, mode, unsignedp, |
c5d5d461 | 3051 | default_label); |
28d81abb RK |
3052 | } |
3053 | ||
3054 | emit_case_nodes (index, node->left, default_label, index_type); | |
3055 | } | |
3056 | else | |
3057 | /* We cannot process node->left normally | |
3058 | since we haven't ruled out the numbers less than | |
3059 | this node's value. So handle node->left explicitly. */ | |
feb04780 | 3060 | do_jump_if_equal (mode, index, |
69107307 AO |
3061 | convert_modes |
3062 | (mode, imode, | |
84217346 | 3063 | expand_normal (node->left->low), |
69107307 | 3064 | unsignedp), |
28d81abb RK |
3065 | label_rtx (node->left->code_label), unsignedp); |
3066 | } | |
3067 | } | |
3068 | else | |
3069 | { | |
3070 | /* Node is a range. These cases are very similar to those for a single | |
3071 | value, except that we do not start by testing whether this node | |
3072 | is the one to branch to. */ | |
3073 | ||
3074 | if (node->right != 0 && node->left != 0) | |
3075 | { | |
3076 | /* Node has subtrees on both sides. | |
3077 | If the right-hand subtree is bounded, | |
3078 | test for it first, since we can go straight there. | |
3079 | Otherwise, we need to make a branch in the control structure, | |
3080 | then handle the two subtrees. */ | |
3081 | tree test_label = 0; | |
3082 | ||
28d81abb RK |
3083 | if (node_is_bounded (node->right, index_type)) |
3084 | /* Right hand node is fully bounded so we can eliminate any | |
3085 | testing and branch directly to the target code. */ | |
69107307 AO |
3086 | emit_cmp_and_jump_insns (index, |
3087 | convert_modes | |
3088 | (mode, imode, | |
84217346 | 3089 | expand_normal (node->high), |
69107307 | 3090 | unsignedp), |
d43e0b7d | 3091 | GT, NULL_RTX, mode, unsignedp, |
c5d5d461 | 3092 | label_rtx (node->right->code_label)); |
28d81abb RK |
3093 | else |
3094 | { | |
3095 | /* Right hand node requires testing. | |
3096 | Branch to a label where we will handle it later. */ | |
3097 | ||
c2255bc4 AH |
3098 | test_label = build_decl (CURR_INSN_LOCATION, |
3099 | LABEL_DECL, NULL_TREE, NULL_TREE); | |
4381f7c2 | 3100 | emit_cmp_and_jump_insns (index, |
69107307 AO |
3101 | convert_modes |
3102 | (mode, imode, | |
84217346 | 3103 | expand_normal (node->high), |
69107307 | 3104 | unsignedp), |
d43e0b7d | 3105 | GT, NULL_RTX, mode, unsignedp, |
c5d5d461 | 3106 | label_rtx (test_label)); |
28d81abb RK |
3107 | } |
3108 | ||
3109 | /* Value belongs to this node or to the left-hand subtree. */ | |
3110 | ||
69107307 AO |
3111 | emit_cmp_and_jump_insns (index, |
3112 | convert_modes | |
3113 | (mode, imode, | |
84217346 | 3114 | expand_normal (node->low), |
69107307 | 3115 | unsignedp), |
d43e0b7d | 3116 | GE, NULL_RTX, mode, unsignedp, |
c5d5d461 | 3117 | label_rtx (node->code_label)); |
28d81abb RK |
3118 | |
3119 | /* Handle the left-hand subtree. */ | |
3120 | emit_case_nodes (index, node->left, default_label, index_type); | |
3121 | ||
3122 | /* If right node had to be handled later, do that now. */ | |
3123 | ||
3124 | if (test_label) | |
3125 | { | |
3126 | /* If the left-hand subtree fell through, | |
3127 | don't let it fall into the right-hand subtree. */ | |
b7814a18 RG |
3128 | if (default_label) |
3129 | emit_jump (default_label); | |
28d81abb RK |
3130 | |
3131 | expand_label (test_label); | |
3132 | emit_case_nodes (index, node->right, default_label, index_type); | |
3133 | } | |
3134 | } | |
3135 | ||
3136 | else if (node->right != 0 && node->left == 0) | |
3137 | { | |
3138 | /* Deal with values to the left of this node, | |
3139 | if they are possible. */ | |
3140 | if (!node_has_low_bound (node, index_type)) | |
3141 | { | |
4381f7c2 | 3142 | emit_cmp_and_jump_insns (index, |
69107307 AO |
3143 | convert_modes |
3144 | (mode, imode, | |
84217346 | 3145 | expand_normal (node->low), |
69107307 | 3146 | unsignedp), |
d43e0b7d | 3147 | LT, NULL_RTX, mode, unsignedp, |
c5d5d461 | 3148 | default_label); |
28d81abb RK |
3149 | } |
3150 | ||
3151 | /* Value belongs to this node or to the right-hand subtree. */ | |
3152 | ||
69107307 AO |
3153 | emit_cmp_and_jump_insns (index, |
3154 | convert_modes | |
3155 | (mode, imode, | |
84217346 | 3156 | expand_normal (node->high), |
69107307 | 3157 | unsignedp), |
d43e0b7d | 3158 | LE, NULL_RTX, mode, unsignedp, |
c5d5d461 | 3159 | label_rtx (node->code_label)); |
28d81abb RK |
3160 | |
3161 | emit_case_nodes (index, node->right, default_label, index_type); | |
3162 | } | |
3163 | ||
3164 | else if (node->right == 0 && node->left != 0) | |
3165 | { | |
3166 | /* Deal with values to the right of this node, | |
3167 | if they are possible. */ | |
3168 | if (!node_has_high_bound (node, index_type)) | |
3169 | { | |
4381f7c2 | 3170 | emit_cmp_and_jump_insns (index, |
69107307 AO |
3171 | convert_modes |
3172 | (mode, imode, | |
84217346 | 3173 | expand_normal (node->high), |
69107307 | 3174 | unsignedp), |
d43e0b7d | 3175 | GT, NULL_RTX, mode, unsignedp, |
c5d5d461 | 3176 | default_label); |
28d81abb RK |
3177 | } |
3178 | ||
3179 | /* Value belongs to this node or to the left-hand subtree. */ | |
3180 | ||
4381f7c2 | 3181 | emit_cmp_and_jump_insns (index, |
69107307 AO |
3182 | convert_modes |
3183 | (mode, imode, | |
84217346 | 3184 | expand_normal (node->low), |
69107307 | 3185 | unsignedp), |
d43e0b7d | 3186 | GE, NULL_RTX, mode, unsignedp, |
c5d5d461 | 3187 | label_rtx (node->code_label)); |
28d81abb RK |
3188 | |
3189 | emit_case_nodes (index, node->left, default_label, index_type); | |
3190 | } | |
3191 | ||
3192 | else | |
3193 | { | |
3194 | /* Node has no children so we check low and high bounds to remove | |
3195 | redundant tests. Only one of the bounds can exist, | |
3196 | since otherwise this node is bounded--a case tested already. */ | |
923cbdc3 JH |
3197 | int high_bound = node_has_high_bound (node, index_type); |
3198 | int low_bound = node_has_low_bound (node, index_type); | |
28d81abb | 3199 | |
923cbdc3 | 3200 | if (!high_bound && low_bound) |
28d81abb | 3201 | { |
4381f7c2 | 3202 | emit_cmp_and_jump_insns (index, |
69107307 AO |
3203 | convert_modes |
3204 | (mode, imode, | |
84217346 | 3205 | expand_normal (node->high), |
69107307 | 3206 | unsignedp), |
d43e0b7d | 3207 | GT, NULL_RTX, mode, unsignedp, |
c5d5d461 | 3208 | default_label); |
28d81abb RK |
3209 | } |
3210 | ||
923cbdc3 | 3211 | else if (!low_bound && high_bound) |
28d81abb | 3212 | { |
4381f7c2 | 3213 | emit_cmp_and_jump_insns (index, |
69107307 AO |
3214 | convert_modes |
3215 | (mode, imode, | |
84217346 | 3216 | expand_normal (node->low), |
69107307 | 3217 | unsignedp), |
d43e0b7d | 3218 | LT, NULL_RTX, mode, unsignedp, |
c5d5d461 | 3219 | default_label); |
28d81abb | 3220 | } |
923cbdc3 JH |
3221 | else if (!low_bound && !high_bound) |
3222 | { | |
9312aecc | 3223 | /* Widen LOW and HIGH to the same width as INDEX. */ |
ae2bcd98 | 3224 | tree type = lang_hooks.types.type_for_mode (mode, unsignedp); |
9312aecc JDA |
3225 | tree low = build1 (CONVERT_EXPR, type, node->low); |
3226 | tree high = build1 (CONVERT_EXPR, type, node->high); | |
ef89d648 | 3227 | rtx low_rtx, new_index, new_bound; |
9312aecc JDA |
3228 | |
3229 | /* Instead of doing two branches, emit one unsigned branch for | |
3230 | (index-low) > (high-low). */ | |
84217346 | 3231 | low_rtx = expand_expr (low, NULL_RTX, mode, EXPAND_NORMAL); |
ef89d648 ZW |
3232 | new_index = expand_simple_binop (mode, MINUS, index, low_rtx, |
3233 | NULL_RTX, unsignedp, | |
3234 | OPTAB_WIDEN); | |
4845b383 KH |
3235 | new_bound = expand_expr (fold_build2 (MINUS_EXPR, type, |
3236 | high, low), | |
84217346 | 3237 | NULL_RTX, mode, EXPAND_NORMAL); |
786de7eb | 3238 | |
9312aecc | 3239 | emit_cmp_and_jump_insns (new_index, new_bound, GT, NULL_RTX, |
d43e0b7d | 3240 | mode, 1, default_label); |
923cbdc3 | 3241 | } |
28d81abb RK |
3242 | |
3243 | emit_jump (label_rtx (node->code_label)); | |
3244 | } | |
3245 | } | |
3246 | } |