tree.c (max_int_size_in_bytes): New function, inspired from code in function.c:assign...
[gcc.git] / gcc / gimplify.c
1 /* Tree lowering pass. This pass converts the GENERIC functions-as-trees
2 tree representation into the GIMPLE form.
3 Copyright (C) 2002, 2003, 2004, 2005, 2006 Free Software Foundation, Inc.
4 Major work done by Sebastian Pop <s.pop@laposte.net>,
5 Diego Novillo <dnovillo@redhat.com> and Jason Merrill <jason@redhat.com>.
6
7 This file is part of GCC.
8
9 GCC is free software; you can redistribute it and/or modify it under
10 the terms of the GNU General Public License as published by the Free
11 Software Foundation; either version 2, or (at your option) any later
12 version.
13
14 GCC is distributed in the hope that it will be useful, but WITHOUT ANY
15 WARRANTY; without even the implied warranty of MERCHANTABILITY or
16 FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
17 for more details.
18
19 You should have received a copy of the GNU General Public License
20 along with GCC; see the file COPYING. If not, write to the Free
21 Software Foundation, 51 Franklin Street, Fifth Floor, Boston, MA
22 02110-1301, USA. */
23
24 #include "config.h"
25 #include "system.h"
26 #include "coretypes.h"
27 #include "tm.h"
28 #include "tree.h"
29 #include "rtl.h"
30 #include "varray.h"
31 #include "tree-gimple.h"
32 #include "tree-inline.h"
33 #include "diagnostic.h"
34 #include "langhooks.h"
35 #include "langhooks-def.h"
36 #include "tree-flow.h"
37 #include "cgraph.h"
38 #include "timevar.h"
39 #include "except.h"
40 #include "hashtab.h"
41 #include "flags.h"
42 #include "real.h"
43 #include "function.h"
44 #include "output.h"
45 #include "expr.h"
46 #include "ggc.h"
47 #include "toplev.h"
48 #include "target.h"
49 #include "optabs.h"
50 #include "pointer-set.h"
51
52
53 enum gimplify_omp_var_data
54 {
55 GOVD_SEEN = 1,
56 GOVD_EXPLICIT = 2,
57 GOVD_SHARED = 4,
58 GOVD_PRIVATE = 8,
59 GOVD_FIRSTPRIVATE = 16,
60 GOVD_LASTPRIVATE = 32,
61 GOVD_REDUCTION = 64,
62 GOVD_LOCAL = 128,
63 GOVD_DEBUG_PRIVATE = 256,
64 GOVD_DATA_SHARE_CLASS = (GOVD_SHARED | GOVD_PRIVATE | GOVD_FIRSTPRIVATE
65 | GOVD_LASTPRIVATE | GOVD_REDUCTION | GOVD_LOCAL)
66 };
67
68 struct gimplify_omp_ctx
69 {
70 struct gimplify_omp_ctx *outer_context;
71 splay_tree variables;
72 struct pointer_set_t *privatized_types;
73 location_t location;
74 enum omp_clause_default_kind default_kind;
75 bool is_parallel;
76 bool is_combined_parallel;
77 };
78
79 struct gimplify_ctx
80 {
81 struct gimplify_ctx *prev_context;
82
83 tree current_bind_expr;
84 tree temps;
85 tree conditional_cleanups;
86 tree exit_label;
87 tree return_temp;
88
89 VEC(tree,heap) *case_labels;
90 /* The formal temporary table. Should this be persistent? */
91 htab_t temp_htab;
92
93 int conditions;
94 bool save_stack;
95 bool into_ssa;
96 };
97
98 static struct gimplify_ctx *gimplify_ctxp;
99 static struct gimplify_omp_ctx *gimplify_omp_ctxp;
100
101
102
103 /* Formal (expression) temporary table handling: Multiple occurrences of
104 the same scalar expression are evaluated into the same temporary. */
105
106 typedef struct gimple_temp_hash_elt
107 {
108 tree val; /* Key */
109 tree temp; /* Value */
110 } elt_t;
111
112 /* Forward declarations. */
113 static enum gimplify_status gimplify_compound_expr (tree *, tree *, bool);
114 #ifdef ENABLE_CHECKING
115 static bool cpt_same_type (tree a, tree b);
116 #endif
117
118
119 /* Return a hash value for a formal temporary table entry. */
120
121 static hashval_t
122 gimple_tree_hash (const void *p)
123 {
124 tree t = ((const elt_t *) p)->val;
125 return iterative_hash_expr (t, 0);
126 }
127
128 /* Compare two formal temporary table entries. */
129
130 static int
131 gimple_tree_eq (const void *p1, const void *p2)
132 {
133 tree t1 = ((const elt_t *) p1)->val;
134 tree t2 = ((const elt_t *) p2)->val;
135 enum tree_code code = TREE_CODE (t1);
136
137 if (TREE_CODE (t2) != code
138 || TREE_TYPE (t1) != TREE_TYPE (t2))
139 return 0;
140
141 if (!operand_equal_p (t1, t2, 0))
142 return 0;
143
144 /* Only allow them to compare equal if they also hash equal; otherwise
145 results are nondeterminate, and we fail bootstrap comparison. */
146 gcc_assert (gimple_tree_hash (p1) == gimple_tree_hash (p2));
147
148 return 1;
149 }
150
151 /* Set up a context for the gimplifier. */
152
153 void
154 push_gimplify_context (void)
155 {
156 struct gimplify_ctx *c;
157
158 c = (struct gimplify_ctx *) xcalloc (1, sizeof (struct gimplify_ctx));
159 c->prev_context = gimplify_ctxp;
160 if (optimize)
161 c->temp_htab = htab_create (1000, gimple_tree_hash, gimple_tree_eq, free);
162
163 gimplify_ctxp = c;
164 }
165
166 /* Tear down a context for the gimplifier. If BODY is non-null, then
167 put the temporaries into the outer BIND_EXPR. Otherwise, put them
168 in the unexpanded_var_list. */
169
170 void
171 pop_gimplify_context (tree body)
172 {
173 struct gimplify_ctx *c = gimplify_ctxp;
174 tree t;
175
176 gcc_assert (c && !c->current_bind_expr);
177 gimplify_ctxp = c->prev_context;
178
179 for (t = c->temps; t ; t = TREE_CHAIN (t))
180 DECL_GIMPLE_FORMAL_TEMP_P (t) = 0;
181
182 if (body)
183 declare_vars (c->temps, body, false);
184 else
185 record_vars (c->temps);
186
187 if (optimize)
188 htab_delete (c->temp_htab);
189 free (c);
190 }
191
192 static void
193 gimple_push_bind_expr (tree bind)
194 {
195 TREE_CHAIN (bind) = gimplify_ctxp->current_bind_expr;
196 gimplify_ctxp->current_bind_expr = bind;
197 }
198
199 static void
200 gimple_pop_bind_expr (void)
201 {
202 gimplify_ctxp->current_bind_expr
203 = TREE_CHAIN (gimplify_ctxp->current_bind_expr);
204 }
205
206 tree
207 gimple_current_bind_expr (void)
208 {
209 return gimplify_ctxp->current_bind_expr;
210 }
211
212 /* Returns true iff there is a COND_EXPR between us and the innermost
213 CLEANUP_POINT_EXPR. This info is used by gimple_push_cleanup. */
214
215 static bool
216 gimple_conditional_context (void)
217 {
218 return gimplify_ctxp->conditions > 0;
219 }
220
221 /* Note that we've entered a COND_EXPR. */
222
223 static void
224 gimple_push_condition (void)
225 {
226 #ifdef ENABLE_CHECKING
227 if (gimplify_ctxp->conditions == 0)
228 gcc_assert (!gimplify_ctxp->conditional_cleanups);
229 #endif
230 ++(gimplify_ctxp->conditions);
231 }
232
233 /* Note that we've left a COND_EXPR. If we're back at unconditional scope
234 now, add any conditional cleanups we've seen to the prequeue. */
235
236 static void
237 gimple_pop_condition (tree *pre_p)
238 {
239 int conds = --(gimplify_ctxp->conditions);
240
241 gcc_assert (conds >= 0);
242 if (conds == 0)
243 {
244 append_to_statement_list (gimplify_ctxp->conditional_cleanups, pre_p);
245 gimplify_ctxp->conditional_cleanups = NULL_TREE;
246 }
247 }
248
249 /* A stable comparison routine for use with splay trees and DECLs. */
250
251 static int
252 splay_tree_compare_decl_uid (splay_tree_key xa, splay_tree_key xb)
253 {
254 tree a = (tree) xa;
255 tree b = (tree) xb;
256
257 return DECL_UID (a) - DECL_UID (b);
258 }
259
260 /* Create a new omp construct that deals with variable remapping. */
261
262 static struct gimplify_omp_ctx *
263 new_omp_context (bool is_parallel, bool is_combined_parallel)
264 {
265 struct gimplify_omp_ctx *c;
266
267 c = XCNEW (struct gimplify_omp_ctx);
268 c->outer_context = gimplify_omp_ctxp;
269 c->variables = splay_tree_new (splay_tree_compare_decl_uid, 0, 0);
270 c->privatized_types = pointer_set_create ();
271 c->location = input_location;
272 c->is_parallel = is_parallel;
273 c->is_combined_parallel = is_combined_parallel;
274 c->default_kind = OMP_CLAUSE_DEFAULT_SHARED;
275
276 return c;
277 }
278
279 /* Destroy an omp construct that deals with variable remapping. */
280
281 static void
282 delete_omp_context (struct gimplify_omp_ctx *c)
283 {
284 splay_tree_delete (c->variables);
285 pointer_set_destroy (c->privatized_types);
286 XDELETE (c);
287 }
288
289 static void omp_add_variable (struct gimplify_omp_ctx *, tree, unsigned int);
290 static bool omp_notice_variable (struct gimplify_omp_ctx *, tree, bool);
291
292 /* A subroutine of append_to_statement_list{,_force}. T is not NULL. */
293
294 static void
295 append_to_statement_list_1 (tree t, tree *list_p)
296 {
297 tree list = *list_p;
298 tree_stmt_iterator i;
299
300 if (!list)
301 {
302 if (t && TREE_CODE (t) == STATEMENT_LIST)
303 {
304 *list_p = t;
305 return;
306 }
307 *list_p = list = alloc_stmt_list ();
308 }
309
310 i = tsi_last (list);
311 tsi_link_after (&i, t, TSI_CONTINUE_LINKING);
312 }
313
314 /* Add T to the end of the list container pointed to by LIST_P.
315 If T is an expression with no effects, it is ignored. */
316
317 void
318 append_to_statement_list (tree t, tree *list_p)
319 {
320 if (t && TREE_SIDE_EFFECTS (t))
321 append_to_statement_list_1 (t, list_p);
322 }
323
324 /* Similar, but the statement is always added, regardless of side effects. */
325
326 void
327 append_to_statement_list_force (tree t, tree *list_p)
328 {
329 if (t != NULL_TREE)
330 append_to_statement_list_1 (t, list_p);
331 }
332
333 /* Both gimplify the statement T and append it to LIST_P. */
334
335 void
336 gimplify_and_add (tree t, tree *list_p)
337 {
338 gimplify_stmt (&t);
339 append_to_statement_list (t, list_p);
340 }
341
342 /* Strip off a legitimate source ending from the input string NAME of
343 length LEN. Rather than having to know the names used by all of
344 our front ends, we strip off an ending of a period followed by
345 up to five characters. (Java uses ".class".) */
346
347 static inline void
348 remove_suffix (char *name, int len)
349 {
350 int i;
351
352 for (i = 2; i < 8 && len > i; i++)
353 {
354 if (name[len - i] == '.')
355 {
356 name[len - i] = '\0';
357 break;
358 }
359 }
360 }
361
362 /* Create a nameless artificial label and put it in the current function
363 context. Returns the newly created label. */
364
365 tree
366 create_artificial_label (void)
367 {
368 tree lab = build_decl (LABEL_DECL, NULL_TREE, void_type_node);
369
370 DECL_ARTIFICIAL (lab) = 1;
371 DECL_IGNORED_P (lab) = 1;
372 DECL_CONTEXT (lab) = current_function_decl;
373 return lab;
374 }
375
376 /* Subroutine for find_single_pointer_decl. */
377
378 static tree
379 find_single_pointer_decl_1 (tree *tp, int *walk_subtrees ATTRIBUTE_UNUSED,
380 void *data)
381 {
382 tree *pdecl = (tree *) data;
383
384 if (DECL_P (*tp) && POINTER_TYPE_P (TREE_TYPE (*tp)))
385 {
386 if (*pdecl)
387 {
388 /* We already found a pointer decl; return anything other
389 than NULL_TREE to unwind from walk_tree signalling that
390 we have a duplicate. */
391 return *tp;
392 }
393 *pdecl = *tp;
394 }
395
396 return NULL_TREE;
397 }
398
399 /* Find the single DECL of pointer type in the tree T and return it.
400 If there are zero or more than one such DECLs, return NULL. */
401
402 static tree
403 find_single_pointer_decl (tree t)
404 {
405 tree decl = NULL_TREE;
406
407 if (walk_tree (&t, find_single_pointer_decl_1, &decl, NULL))
408 {
409 /* find_single_pointer_decl_1 returns a nonzero value, causing
410 walk_tree to return a nonzero value, to indicate that it
411 found more than one pointer DECL. */
412 return NULL_TREE;
413 }
414
415 return decl;
416 }
417
418 /* Create a new temporary name with PREFIX. Returns an identifier. */
419
420 static GTY(()) unsigned int tmp_var_id_num;
421
422 tree
423 create_tmp_var_name (const char *prefix)
424 {
425 char *tmp_name;
426
427 if (prefix)
428 {
429 char *preftmp = ASTRDUP (prefix);
430
431 remove_suffix (preftmp, strlen (preftmp));
432 prefix = preftmp;
433 }
434
435 ASM_FORMAT_PRIVATE_NAME (tmp_name, prefix ? prefix : "T", tmp_var_id_num++);
436 return get_identifier (tmp_name);
437 }
438
439
440 /* Create a new temporary variable declaration of type TYPE.
441 Does NOT push it into the current binding. */
442
443 tree
444 create_tmp_var_raw (tree type, const char *prefix)
445 {
446 tree tmp_var;
447 tree new_type;
448
449 /* Make the type of the variable writable. */
450 new_type = build_type_variant (type, 0, 0);
451 TYPE_ATTRIBUTES (new_type) = TYPE_ATTRIBUTES (type);
452
453 tmp_var = build_decl (VAR_DECL, prefix ? create_tmp_var_name (prefix) : NULL,
454 type);
455
456 /* The variable was declared by the compiler. */
457 DECL_ARTIFICIAL (tmp_var) = 1;
458 /* And we don't want debug info for it. */
459 DECL_IGNORED_P (tmp_var) = 1;
460
461 /* Make the variable writable. */
462 TREE_READONLY (tmp_var) = 0;
463
464 DECL_EXTERNAL (tmp_var) = 0;
465 TREE_STATIC (tmp_var) = 0;
466 TREE_USED (tmp_var) = 1;
467
468 return tmp_var;
469 }
470
471 /* Create a new temporary variable declaration of type TYPE. DOES push the
472 variable into the current binding. Further, assume that this is called
473 only from gimplification or optimization, at which point the creation of
474 certain types are bugs. */
475
476 tree
477 create_tmp_var (tree type, const char *prefix)
478 {
479 tree tmp_var;
480
481 /* We don't allow types that are addressable (meaning we can't make copies),
482 or incomplete. We also used to reject every variable size objects here,
483 but now support those for which a constant upper bound can be obtained.
484 The processing for variable sizes is performed in gimple_add_tmp_var,
485 point at which it really matters and possibly reached via paths not going
486 through this function, e.g. after direct calls to create_tmp_var_raw. */
487 gcc_assert (!TREE_ADDRESSABLE (type) && COMPLETE_TYPE_P (type));
488
489 tmp_var = create_tmp_var_raw (type, prefix);
490 gimple_add_tmp_var (tmp_var);
491 return tmp_var;
492 }
493
494 /* Given a tree, try to return a useful variable name that we can use
495 to prefix a temporary that is being assigned the value of the tree.
496 I.E. given <temp> = &A, return A. */
497
498 const char *
499 get_name (tree t)
500 {
501 tree stripped_decl;
502
503 stripped_decl = t;
504 STRIP_NOPS (stripped_decl);
505 if (DECL_P (stripped_decl) && DECL_NAME (stripped_decl))
506 return IDENTIFIER_POINTER (DECL_NAME (stripped_decl));
507 else
508 {
509 switch (TREE_CODE (stripped_decl))
510 {
511 case ADDR_EXPR:
512 return get_name (TREE_OPERAND (stripped_decl, 0));
513 break;
514 default:
515 return NULL;
516 }
517 }
518 }
519
520 /* Create a temporary with a name derived from VAL. Subroutine of
521 lookup_tmp_var; nobody else should call this function. */
522
523 static inline tree
524 create_tmp_from_val (tree val)
525 {
526 return create_tmp_var (TYPE_MAIN_VARIANT (TREE_TYPE (val)), get_name (val));
527 }
528
529 /* Create a temporary to hold the value of VAL. If IS_FORMAL, try to reuse
530 an existing expression temporary. */
531
532 static tree
533 lookup_tmp_var (tree val, bool is_formal)
534 {
535 tree ret;
536
537 /* If not optimizing, never really reuse a temporary. local-alloc
538 won't allocate any variable that is used in more than one basic
539 block, which means it will go into memory, causing much extra
540 work in reload and final and poorer code generation, outweighing
541 the extra memory allocation here. */
542 if (!optimize || !is_formal || TREE_SIDE_EFFECTS (val))
543 ret = create_tmp_from_val (val);
544 else
545 {
546 elt_t elt, *elt_p;
547 void **slot;
548
549 elt.val = val;
550 slot = htab_find_slot (gimplify_ctxp->temp_htab, (void *)&elt, INSERT);
551 if (*slot == NULL)
552 {
553 elt_p = XNEW (elt_t);
554 elt_p->val = val;
555 elt_p->temp = ret = create_tmp_from_val (val);
556 *slot = (void *) elt_p;
557 }
558 else
559 {
560 elt_p = (elt_t *) *slot;
561 ret = elt_p->temp;
562 }
563 }
564
565 if (is_formal)
566 DECL_GIMPLE_FORMAL_TEMP_P (ret) = 1;
567
568 return ret;
569 }
570
571 /* Returns a formal temporary variable initialized with VAL. PRE_P is as
572 in gimplify_expr. Only use this function if:
573
574 1) The value of the unfactored expression represented by VAL will not
575 change between the initialization and use of the temporary, and
576 2) The temporary will not be otherwise modified.
577
578 For instance, #1 means that this is inappropriate for SAVE_EXPR temps,
579 and #2 means it is inappropriate for && temps.
580
581 For other cases, use get_initialized_tmp_var instead. */
582
583 static tree
584 internal_get_tmp_var (tree val, tree *pre_p, tree *post_p, bool is_formal)
585 {
586 tree t, mod;
587
588 gimplify_expr (&val, pre_p, post_p, is_gimple_formal_tmp_rhs, fb_rvalue);
589
590 t = lookup_tmp_var (val, is_formal);
591
592 if (is_formal)
593 {
594 tree u = find_single_pointer_decl (val);
595
596 if (u && TREE_CODE (u) == VAR_DECL && DECL_BASED_ON_RESTRICT_P (u))
597 u = DECL_GET_RESTRICT_BASE (u);
598 if (u && TYPE_RESTRICT (TREE_TYPE (u)))
599 {
600 if (DECL_BASED_ON_RESTRICT_P (t))
601 gcc_assert (u == DECL_GET_RESTRICT_BASE (t));
602 else
603 {
604 DECL_BASED_ON_RESTRICT_P (t) = 1;
605 SET_DECL_RESTRICT_BASE (t, u);
606 }
607 }
608 }
609
610 if (TREE_CODE (TREE_TYPE (t)) == COMPLEX_TYPE)
611 DECL_COMPLEX_GIMPLE_REG_P (t) = 1;
612
613 mod = build2 (INIT_EXPR, TREE_TYPE (t), t, val);
614
615 if (EXPR_HAS_LOCATION (val))
616 SET_EXPR_LOCUS (mod, EXPR_LOCUS (val));
617 else
618 SET_EXPR_LOCATION (mod, input_location);
619
620 /* gimplify_modify_expr might want to reduce this further. */
621 gimplify_and_add (mod, pre_p);
622
623 /* If we're gimplifying into ssa, gimplify_modify_expr will have
624 given our temporary an ssa name. Find and return it. */
625 if (gimplify_ctxp->into_ssa)
626 t = TREE_OPERAND (mod, 0);
627
628 return t;
629 }
630
631 /* Returns a formal temporary variable initialized with VAL. PRE_P
632 points to a statement list where side-effects needed to compute VAL
633 should be stored. */
634
635 tree
636 get_formal_tmp_var (tree val, tree *pre_p)
637 {
638 return internal_get_tmp_var (val, pre_p, NULL, true);
639 }
640
641 /* Returns a temporary variable initialized with VAL. PRE_P and POST_P
642 are as in gimplify_expr. */
643
644 tree
645 get_initialized_tmp_var (tree val, tree *pre_p, tree *post_p)
646 {
647 return internal_get_tmp_var (val, pre_p, post_p, false);
648 }
649
650 /* Declares all the variables in VARS in SCOPE. If DEBUG_INFO is
651 true, generate debug info for them; otherwise don't. */
652
653 void
654 declare_vars (tree vars, tree scope, bool debug_info)
655 {
656 tree last = vars;
657 if (last)
658 {
659 tree temps, block;
660
661 /* C99 mode puts the default 'return 0;' for main outside the outer
662 braces. So drill down until we find an actual scope. */
663 while (TREE_CODE (scope) == COMPOUND_EXPR)
664 scope = TREE_OPERAND (scope, 0);
665
666 gcc_assert (TREE_CODE (scope) == BIND_EXPR);
667
668 temps = nreverse (last);
669
670 block = BIND_EXPR_BLOCK (scope);
671 if (!block || !debug_info)
672 {
673 TREE_CHAIN (last) = BIND_EXPR_VARS (scope);
674 BIND_EXPR_VARS (scope) = temps;
675 }
676 else
677 {
678 /* We need to attach the nodes both to the BIND_EXPR and to its
679 associated BLOCK for debugging purposes. The key point here
680 is that the BLOCK_VARS of the BIND_EXPR_BLOCK of a BIND_EXPR
681 is a subchain of the BIND_EXPR_VARS of the BIND_EXPR. */
682 if (BLOCK_VARS (block))
683 BLOCK_VARS (block) = chainon (BLOCK_VARS (block), temps);
684 else
685 {
686 BIND_EXPR_VARS (scope) = chainon (BIND_EXPR_VARS (scope), temps);
687 BLOCK_VARS (block) = temps;
688 }
689 }
690 }
691 }
692
693 /* For VAR a VAR_DECL of variable size, try to find a constant upper bound
694 for the size and adjust DECL_SIZE/DECL_SIZE_UNIT accordingly. Abort if
695 no such upper bound can be obtained. */
696
697 static void
698 force_constant_size (tree var)
699 {
700 /* The only attempt we make is by querying the maximum size of objects
701 of the variable's type. */
702
703 HOST_WIDE_INT max_size;
704
705 gcc_assert (TREE_CODE (var) == VAR_DECL);
706
707 max_size = max_int_size_in_bytes (TREE_TYPE (var));
708
709 gcc_assert (max_size >= 0);
710
711 DECL_SIZE_UNIT (var)
712 = build_int_cst (TREE_TYPE (DECL_SIZE_UNIT (var)), max_size);
713 DECL_SIZE (var)
714 = build_int_cst (TREE_TYPE (DECL_SIZE (var)), max_size * BITS_PER_UNIT);
715 }
716
717 void
718 gimple_add_tmp_var (tree tmp)
719 {
720 gcc_assert (!TREE_CHAIN (tmp) && !DECL_SEEN_IN_BIND_EXPR_P (tmp));
721
722 /* Later processing assumes that the object size is constant, which might
723 not be true at this point. Force the use of a constant upper bound in
724 this case. */
725 if (!host_integerp (DECL_SIZE_UNIT (tmp), 1))
726 force_constant_size (tmp);
727
728 DECL_CONTEXT (tmp) = current_function_decl;
729 DECL_SEEN_IN_BIND_EXPR_P (tmp) = 1;
730
731 if (gimplify_ctxp)
732 {
733 TREE_CHAIN (tmp) = gimplify_ctxp->temps;
734 gimplify_ctxp->temps = tmp;
735
736 /* Mark temporaries local within the nearest enclosing parallel. */
737 if (gimplify_omp_ctxp)
738 {
739 struct gimplify_omp_ctx *ctx = gimplify_omp_ctxp;
740 while (ctx && !ctx->is_parallel)
741 ctx = ctx->outer_context;
742 if (ctx)
743 omp_add_variable (ctx, tmp, GOVD_LOCAL | GOVD_SEEN);
744 }
745 }
746 else if (cfun)
747 record_vars (tmp);
748 else
749 declare_vars (tmp, DECL_SAVED_TREE (current_function_decl), false);
750 }
751
752 /* Determines whether to assign a locus to the statement STMT. */
753
754 static bool
755 should_carry_locus_p (tree stmt)
756 {
757 /* Don't emit a line note for a label. We particularly don't want to
758 emit one for the break label, since it doesn't actually correspond
759 to the beginning of the loop/switch. */
760 if (TREE_CODE (stmt) == LABEL_EXPR)
761 return false;
762
763 /* Do not annotate empty statements, since it confuses gcov. */
764 if (!TREE_SIDE_EFFECTS (stmt))
765 return false;
766
767 return true;
768 }
769
770 static void
771 annotate_one_with_locus (tree t, location_t locus)
772 {
773 if (EXPR_P (t) && ! EXPR_HAS_LOCATION (t) && should_carry_locus_p (t))
774 SET_EXPR_LOCATION (t, locus);
775 }
776
777 void
778 annotate_all_with_locus (tree *stmt_p, location_t locus)
779 {
780 tree_stmt_iterator i;
781
782 if (!*stmt_p)
783 return;
784
785 for (i = tsi_start (*stmt_p); !tsi_end_p (i); tsi_next (&i))
786 {
787 tree t = tsi_stmt (i);
788
789 /* Assuming we've already been gimplified, we shouldn't
790 see nested chaining constructs anymore. */
791 gcc_assert (TREE_CODE (t) != STATEMENT_LIST
792 && TREE_CODE (t) != COMPOUND_EXPR);
793
794 annotate_one_with_locus (t, locus);
795 }
796 }
797
798 /* Similar to copy_tree_r() but do not copy SAVE_EXPR or TARGET_EXPR nodes.
799 These nodes model computations that should only be done once. If we
800 were to unshare something like SAVE_EXPR(i++), the gimplification
801 process would create wrong code. */
802
803 static tree
804 mostly_copy_tree_r (tree *tp, int *walk_subtrees, void *data)
805 {
806 enum tree_code code = TREE_CODE (*tp);
807 /* Don't unshare types, decls, constants and SAVE_EXPR nodes. */
808 if (TREE_CODE_CLASS (code) == tcc_type
809 || TREE_CODE_CLASS (code) == tcc_declaration
810 || TREE_CODE_CLASS (code) == tcc_constant
811 || code == SAVE_EXPR || code == TARGET_EXPR
812 /* We can't do anything sensible with a BLOCK used as an expression,
813 but we also can't just die when we see it because of non-expression
814 uses. So just avert our eyes and cross our fingers. Silly Java. */
815 || code == BLOCK)
816 *walk_subtrees = 0;
817 else
818 {
819 gcc_assert (code != BIND_EXPR);
820 copy_tree_r (tp, walk_subtrees, data);
821 }
822
823 return NULL_TREE;
824 }
825
826 /* Callback for walk_tree to unshare most of the shared trees rooted at
827 *TP. If *TP has been visited already (i.e., TREE_VISITED (*TP) == 1),
828 then *TP is deep copied by calling copy_tree_r.
829
830 This unshares the same trees as copy_tree_r with the exception of
831 SAVE_EXPR nodes. These nodes model computations that should only be
832 done once. If we were to unshare something like SAVE_EXPR(i++), the
833 gimplification process would create wrong code. */
834
835 static tree
836 copy_if_shared_r (tree *tp, int *walk_subtrees ATTRIBUTE_UNUSED,
837 void *data ATTRIBUTE_UNUSED)
838 {
839 tree t = *tp;
840 enum tree_code code = TREE_CODE (t);
841
842 /* Skip types, decls, and constants. But we do want to look at their
843 types and the bounds of types. Mark them as visited so we properly
844 unmark their subtrees on the unmark pass. If we've already seen them,
845 don't look down further. */
846 if (TREE_CODE_CLASS (code) == tcc_type
847 || TREE_CODE_CLASS (code) == tcc_declaration
848 || TREE_CODE_CLASS (code) == tcc_constant)
849 {
850 if (TREE_VISITED (t))
851 *walk_subtrees = 0;
852 else
853 TREE_VISITED (t) = 1;
854 }
855
856 /* If this node has been visited already, unshare it and don't look
857 any deeper. */
858 else if (TREE_VISITED (t))
859 {
860 walk_tree (tp, mostly_copy_tree_r, NULL, NULL);
861 *walk_subtrees = 0;
862 }
863
864 /* Otherwise, mark the tree as visited and keep looking. */
865 else
866 TREE_VISITED (t) = 1;
867
868 return NULL_TREE;
869 }
870
871 static tree
872 unmark_visited_r (tree *tp, int *walk_subtrees ATTRIBUTE_UNUSED,
873 void *data ATTRIBUTE_UNUSED)
874 {
875 if (TREE_VISITED (*tp))
876 TREE_VISITED (*tp) = 0;
877 else
878 *walk_subtrees = 0;
879
880 return NULL_TREE;
881 }
882
883 /* Unshare all the trees in BODY_P, a pointer into the body of FNDECL, and the
884 bodies of any nested functions if we are unsharing the entire body of
885 FNDECL. */
886
887 static void
888 unshare_body (tree *body_p, tree fndecl)
889 {
890 struct cgraph_node *cgn = cgraph_node (fndecl);
891
892 walk_tree (body_p, copy_if_shared_r, NULL, NULL);
893 if (body_p == &DECL_SAVED_TREE (fndecl))
894 for (cgn = cgn->nested; cgn; cgn = cgn->next_nested)
895 unshare_body (&DECL_SAVED_TREE (cgn->decl), cgn->decl);
896 }
897
898 /* Likewise, but mark all trees as not visited. */
899
900 static void
901 unvisit_body (tree *body_p, tree fndecl)
902 {
903 struct cgraph_node *cgn = cgraph_node (fndecl);
904
905 walk_tree (body_p, unmark_visited_r, NULL, NULL);
906 if (body_p == &DECL_SAVED_TREE (fndecl))
907 for (cgn = cgn->nested; cgn; cgn = cgn->next_nested)
908 unvisit_body (&DECL_SAVED_TREE (cgn->decl), cgn->decl);
909 }
910
911 /* Unshare T and all the trees reached from T via TREE_CHAIN. */
912
913 static void
914 unshare_all_trees (tree t)
915 {
916 walk_tree (&t, copy_if_shared_r, NULL, NULL);
917 walk_tree (&t, unmark_visited_r, NULL, NULL);
918 }
919
920 /* Unconditionally make an unshared copy of EXPR. This is used when using
921 stored expressions which span multiple functions, such as BINFO_VTABLE,
922 as the normal unsharing process can't tell that they're shared. */
923
924 tree
925 unshare_expr (tree expr)
926 {
927 walk_tree (&expr, mostly_copy_tree_r, NULL, NULL);
928 return expr;
929 }
930
931 /* A terser interface for building a representation of an exception
932 specification. */
933
934 tree
935 gimple_build_eh_filter (tree body, tree allowed, tree failure)
936 {
937 tree t;
938
939 /* FIXME should the allowed types go in TREE_TYPE? */
940 t = build2 (EH_FILTER_EXPR, void_type_node, allowed, NULL_TREE);
941 append_to_statement_list (failure, &EH_FILTER_FAILURE (t));
942
943 t = build2 (TRY_CATCH_EXPR, void_type_node, NULL_TREE, t);
944 append_to_statement_list (body, &TREE_OPERAND (t, 0));
945
946 return t;
947 }
948
949 \f
950 /* WRAPPER is a code such as BIND_EXPR or CLEANUP_POINT_EXPR which can both
951 contain statements and have a value. Assign its value to a temporary
952 and give it void_type_node. Returns the temporary, or NULL_TREE if
953 WRAPPER was already void. */
954
955 tree
956 voidify_wrapper_expr (tree wrapper, tree temp)
957 {
958 if (!VOID_TYPE_P (TREE_TYPE (wrapper)))
959 {
960 tree *p, sub = wrapper;
961
962 restart:
963 /* Set p to point to the body of the wrapper. */
964 switch (TREE_CODE (sub))
965 {
966 case BIND_EXPR:
967 /* For a BIND_EXPR, the body is operand 1. */
968 p = &BIND_EXPR_BODY (sub);
969 break;
970
971 default:
972 p = &TREE_OPERAND (sub, 0);
973 break;
974 }
975
976 /* Advance to the last statement. Set all container types to void. */
977 if (TREE_CODE (*p) == STATEMENT_LIST)
978 {
979 tree_stmt_iterator i = tsi_last (*p);
980 p = tsi_end_p (i) ? NULL : tsi_stmt_ptr (i);
981 }
982 else
983 {
984 for (; TREE_CODE (*p) == COMPOUND_EXPR; p = &TREE_OPERAND (*p, 1))
985 {
986 TREE_SIDE_EFFECTS (*p) = 1;
987 TREE_TYPE (*p) = void_type_node;
988 }
989 }
990
991 if (p == NULL || IS_EMPTY_STMT (*p))
992 ;
993 /* Look through exception handling. */
994 else if (TREE_CODE (*p) == TRY_FINALLY_EXPR
995 || TREE_CODE (*p) == TRY_CATCH_EXPR)
996 {
997 sub = *p;
998 goto restart;
999 }
1000 /* The C++ frontend already did this for us. */
1001 else if (TREE_CODE (*p) == INIT_EXPR
1002 || TREE_CODE (*p) == TARGET_EXPR)
1003 temp = TREE_OPERAND (*p, 0);
1004 /* If we're returning a dereference, move the dereference
1005 outside the wrapper. */
1006 else if (TREE_CODE (*p) == INDIRECT_REF)
1007 {
1008 tree ptr = TREE_OPERAND (*p, 0);
1009 temp = create_tmp_var (TREE_TYPE (ptr), "retval");
1010 *p = build2 (MODIFY_EXPR, TREE_TYPE (ptr), temp, ptr);
1011 temp = build1 (INDIRECT_REF, TREE_TYPE (TREE_TYPE (temp)), temp);
1012 /* If this is a BIND_EXPR for a const inline function, it might not
1013 have TREE_SIDE_EFFECTS set. That is no longer accurate. */
1014 TREE_SIDE_EFFECTS (wrapper) = 1;
1015 }
1016 else
1017 {
1018 if (!temp)
1019 temp = create_tmp_var (TREE_TYPE (wrapper), "retval");
1020 *p = build2 (MODIFY_EXPR, TREE_TYPE (temp), temp, *p);
1021 TREE_SIDE_EFFECTS (wrapper) = 1;
1022 }
1023
1024 TREE_TYPE (wrapper) = void_type_node;
1025 return temp;
1026 }
1027
1028 return NULL_TREE;
1029 }
1030
1031 /* Prepare calls to builtins to SAVE and RESTORE the stack as well as
1032 a temporary through which they communicate. */
1033
1034 static void
1035 build_stack_save_restore (tree *save, tree *restore)
1036 {
1037 tree save_call, tmp_var;
1038
1039 save_call =
1040 build_function_call_expr (implicit_built_in_decls[BUILT_IN_STACK_SAVE],
1041 NULL_TREE);
1042 tmp_var = create_tmp_var (ptr_type_node, "saved_stack");
1043
1044 *save = build2 (MODIFY_EXPR, ptr_type_node, tmp_var, save_call);
1045 *restore =
1046 build_function_call_expr (implicit_built_in_decls[BUILT_IN_STACK_RESTORE],
1047 tree_cons (NULL_TREE, tmp_var, NULL_TREE));
1048 }
1049
1050 /* Gimplify a BIND_EXPR. Just voidify and recurse. */
1051
1052 static enum gimplify_status
1053 gimplify_bind_expr (tree *expr_p, tree temp, tree *pre_p)
1054 {
1055 tree bind_expr = *expr_p;
1056 bool old_save_stack = gimplify_ctxp->save_stack;
1057 tree t;
1058
1059 temp = voidify_wrapper_expr (bind_expr, temp);
1060
1061 /* Mark variables seen in this bind expr. */
1062 for (t = BIND_EXPR_VARS (bind_expr); t ; t = TREE_CHAIN (t))
1063 {
1064 if (TREE_CODE (t) == VAR_DECL)
1065 {
1066 struct gimplify_omp_ctx *ctx = gimplify_omp_ctxp;
1067
1068 /* Mark variable as local. */
1069 if (ctx && !is_global_var (t)
1070 && (! DECL_SEEN_IN_BIND_EXPR_P (t)
1071 || splay_tree_lookup (ctx->variables,
1072 (splay_tree_key) t) == NULL))
1073 omp_add_variable (gimplify_omp_ctxp, t, GOVD_LOCAL | GOVD_SEEN);
1074
1075 DECL_SEEN_IN_BIND_EXPR_P (t) = 1;
1076 }
1077
1078 /* Preliminarily mark non-addressed complex variables as eligible
1079 for promotion to gimple registers. We'll transform their uses
1080 as we find them. */
1081 if (TREE_CODE (TREE_TYPE (t)) == COMPLEX_TYPE
1082 && !TREE_THIS_VOLATILE (t)
1083 && (TREE_CODE (t) == VAR_DECL && !DECL_HARD_REGISTER (t))
1084 && !needs_to_live_in_memory (t))
1085 DECL_COMPLEX_GIMPLE_REG_P (t) = 1;
1086 }
1087
1088 gimple_push_bind_expr (bind_expr);
1089 gimplify_ctxp->save_stack = false;
1090
1091 gimplify_to_stmt_list (&BIND_EXPR_BODY (bind_expr));
1092
1093 if (gimplify_ctxp->save_stack)
1094 {
1095 tree stack_save, stack_restore;
1096
1097 /* Save stack on entry and restore it on exit. Add a try_finally
1098 block to achieve this. Note that mudflap depends on the
1099 format of the emitted code: see mx_register_decls(). */
1100 build_stack_save_restore (&stack_save, &stack_restore);
1101
1102 t = build2 (TRY_FINALLY_EXPR, void_type_node,
1103 BIND_EXPR_BODY (bind_expr), NULL_TREE);
1104 append_to_statement_list (stack_restore, &TREE_OPERAND (t, 1));
1105
1106 BIND_EXPR_BODY (bind_expr) = NULL_TREE;
1107 append_to_statement_list (stack_save, &BIND_EXPR_BODY (bind_expr));
1108 append_to_statement_list (t, &BIND_EXPR_BODY (bind_expr));
1109 }
1110
1111 gimplify_ctxp->save_stack = old_save_stack;
1112 gimple_pop_bind_expr ();
1113
1114 if (temp)
1115 {
1116 *expr_p = temp;
1117 append_to_statement_list (bind_expr, pre_p);
1118 return GS_OK;
1119 }
1120 else
1121 return GS_ALL_DONE;
1122 }
1123
1124 /* Gimplify a RETURN_EXPR. If the expression to be returned is not a
1125 GIMPLE value, it is assigned to a new temporary and the statement is
1126 re-written to return the temporary.
1127
1128 PRE_P points to the list where side effects that must happen before
1129 STMT should be stored. */
1130
1131 static enum gimplify_status
1132 gimplify_return_expr (tree stmt, tree *pre_p)
1133 {
1134 tree ret_expr = TREE_OPERAND (stmt, 0);
1135 tree result_decl, result;
1136
1137 if (!ret_expr || TREE_CODE (ret_expr) == RESULT_DECL
1138 || ret_expr == error_mark_node)
1139 return GS_ALL_DONE;
1140
1141 if (VOID_TYPE_P (TREE_TYPE (TREE_TYPE (current_function_decl))))
1142 result_decl = NULL_TREE;
1143 else
1144 {
1145 result_decl = TREE_OPERAND (ret_expr, 0);
1146 if (TREE_CODE (result_decl) == INDIRECT_REF)
1147 /* See through a return by reference. */
1148 result_decl = TREE_OPERAND (result_decl, 0);
1149
1150 gcc_assert ((TREE_CODE (ret_expr) == MODIFY_EXPR
1151 || TREE_CODE (ret_expr) == INIT_EXPR)
1152 && TREE_CODE (result_decl) == RESULT_DECL);
1153 }
1154
1155 /* If aggregate_value_p is true, then we can return the bare RESULT_DECL.
1156 Recall that aggregate_value_p is FALSE for any aggregate type that is
1157 returned in registers. If we're returning values in registers, then
1158 we don't want to extend the lifetime of the RESULT_DECL, particularly
1159 across another call. In addition, for those aggregates for which
1160 hard_function_value generates a PARALLEL, we'll die during normal
1161 expansion of structure assignments; there's special code in expand_return
1162 to handle this case that does not exist in expand_expr. */
1163 if (!result_decl
1164 || aggregate_value_p (result_decl, TREE_TYPE (current_function_decl)))
1165 result = result_decl;
1166 else if (gimplify_ctxp->return_temp)
1167 result = gimplify_ctxp->return_temp;
1168 else
1169 {
1170 result = create_tmp_var (TREE_TYPE (result_decl), NULL);
1171
1172 /* ??? With complex control flow (usually involving abnormal edges),
1173 we can wind up warning about an uninitialized value for this. Due
1174 to how this variable is constructed and initialized, this is never
1175 true. Give up and never warn. */
1176 TREE_NO_WARNING (result) = 1;
1177
1178 gimplify_ctxp->return_temp = result;
1179 }
1180
1181 /* Smash the lhs of the MODIFY_EXPR to the temporary we plan to use.
1182 Then gimplify the whole thing. */
1183 if (result != result_decl)
1184 TREE_OPERAND (ret_expr, 0) = result;
1185
1186 gimplify_and_add (TREE_OPERAND (stmt, 0), pre_p);
1187
1188 /* If we didn't use a temporary, then the result is just the result_decl.
1189 Otherwise we need a simple copy. This should already be gimple. */
1190 if (result == result_decl)
1191 ret_expr = result;
1192 else
1193 ret_expr = build2 (MODIFY_EXPR, TREE_TYPE (result), result_decl, result);
1194 TREE_OPERAND (stmt, 0) = ret_expr;
1195
1196 return GS_ALL_DONE;
1197 }
1198
1199 /* Gimplifies a DECL_EXPR node *STMT_P by making any necessary allocation
1200 and initialization explicit. */
1201
1202 static enum gimplify_status
1203 gimplify_decl_expr (tree *stmt_p)
1204 {
1205 tree stmt = *stmt_p;
1206 tree decl = DECL_EXPR_DECL (stmt);
1207
1208 *stmt_p = NULL_TREE;
1209
1210 if (TREE_TYPE (decl) == error_mark_node)
1211 return GS_ERROR;
1212
1213 if ((TREE_CODE (decl) == TYPE_DECL
1214 || TREE_CODE (decl) == VAR_DECL)
1215 && !TYPE_SIZES_GIMPLIFIED (TREE_TYPE (decl)))
1216 gimplify_type_sizes (TREE_TYPE (decl), stmt_p);
1217
1218 if (TREE_CODE (decl) == VAR_DECL && !DECL_EXTERNAL (decl))
1219 {
1220 tree init = DECL_INITIAL (decl);
1221
1222 if (!TREE_CONSTANT (DECL_SIZE (decl)))
1223 {
1224 /* This is a variable-sized decl. Simplify its size and mark it
1225 for deferred expansion. Note that mudflap depends on the format
1226 of the emitted code: see mx_register_decls(). */
1227 tree t, args, addr, ptr_type;
1228
1229 gimplify_one_sizepos (&DECL_SIZE (decl), stmt_p);
1230 gimplify_one_sizepos (&DECL_SIZE_UNIT (decl), stmt_p);
1231
1232 /* All occurrences of this decl in final gimplified code will be
1233 replaced by indirection. Setting DECL_VALUE_EXPR does two
1234 things: First, it lets the rest of the gimplifier know what
1235 replacement to use. Second, it lets the debug info know
1236 where to find the value. */
1237 ptr_type = build_pointer_type (TREE_TYPE (decl));
1238 addr = create_tmp_var (ptr_type, get_name (decl));
1239 DECL_IGNORED_P (addr) = 0;
1240 t = build_fold_indirect_ref (addr);
1241 SET_DECL_VALUE_EXPR (decl, t);
1242 DECL_HAS_VALUE_EXPR_P (decl) = 1;
1243
1244 args = tree_cons (NULL, DECL_SIZE_UNIT (decl), NULL);
1245 t = built_in_decls[BUILT_IN_ALLOCA];
1246 t = build_function_call_expr (t, args);
1247 t = fold_convert (ptr_type, t);
1248 t = build2 (MODIFY_EXPR, void_type_node, addr, t);
1249
1250 gimplify_and_add (t, stmt_p);
1251
1252 /* Indicate that we need to restore the stack level when the
1253 enclosing BIND_EXPR is exited. */
1254 gimplify_ctxp->save_stack = true;
1255 }
1256
1257 if (init && init != error_mark_node)
1258 {
1259 if (!TREE_STATIC (decl))
1260 {
1261 DECL_INITIAL (decl) = NULL_TREE;
1262 init = build2 (INIT_EXPR, void_type_node, decl, init);
1263 gimplify_and_add (init, stmt_p);
1264 }
1265 else
1266 /* We must still examine initializers for static variables
1267 as they may contain a label address. */
1268 walk_tree (&init, force_labels_r, NULL, NULL);
1269 }
1270
1271 /* Some front ends do not explicitly declare all anonymous
1272 artificial variables. We compensate here by declaring the
1273 variables, though it would be better if the front ends would
1274 explicitly declare them. */
1275 if (!DECL_SEEN_IN_BIND_EXPR_P (decl)
1276 && DECL_ARTIFICIAL (decl) && DECL_NAME (decl) == NULL_TREE)
1277 gimple_add_tmp_var (decl);
1278 }
1279
1280 return GS_ALL_DONE;
1281 }
1282
1283 /* Gimplify a LOOP_EXPR. Normally this just involves gimplifying the body
1284 and replacing the LOOP_EXPR with goto, but if the loop contains an
1285 EXIT_EXPR, we need to append a label for it to jump to. */
1286
1287 static enum gimplify_status
1288 gimplify_loop_expr (tree *expr_p, tree *pre_p)
1289 {
1290 tree saved_label = gimplify_ctxp->exit_label;
1291 tree start_label = build1 (LABEL_EXPR, void_type_node, NULL_TREE);
1292 tree jump_stmt = build_and_jump (&LABEL_EXPR_LABEL (start_label));
1293
1294 append_to_statement_list (start_label, pre_p);
1295
1296 gimplify_ctxp->exit_label = NULL_TREE;
1297
1298 gimplify_and_add (LOOP_EXPR_BODY (*expr_p), pre_p);
1299
1300 if (gimplify_ctxp->exit_label)
1301 {
1302 append_to_statement_list (jump_stmt, pre_p);
1303 *expr_p = build1 (LABEL_EXPR, void_type_node, gimplify_ctxp->exit_label);
1304 }
1305 else
1306 *expr_p = jump_stmt;
1307
1308 gimplify_ctxp->exit_label = saved_label;
1309
1310 return GS_ALL_DONE;
1311 }
1312
1313 /* Compare two case labels. Because the front end should already have
1314 made sure that case ranges do not overlap, it is enough to only compare
1315 the CASE_LOW values of each case label. */
1316
1317 static int
1318 compare_case_labels (const void *p1, const void *p2)
1319 {
1320 tree case1 = *(tree *)p1;
1321 tree case2 = *(tree *)p2;
1322
1323 return tree_int_cst_compare (CASE_LOW (case1), CASE_LOW (case2));
1324 }
1325
1326 /* Sort the case labels in LABEL_VEC in place in ascending order. */
1327
1328 void
1329 sort_case_labels (tree label_vec)
1330 {
1331 size_t len = TREE_VEC_LENGTH (label_vec);
1332 tree default_case = TREE_VEC_ELT (label_vec, len - 1);
1333
1334 if (CASE_LOW (default_case))
1335 {
1336 size_t i;
1337
1338 /* The last label in the vector should be the default case
1339 but it is not. */
1340 for (i = 0; i < len; ++i)
1341 {
1342 tree t = TREE_VEC_ELT (label_vec, i);
1343 if (!CASE_LOW (t))
1344 {
1345 default_case = t;
1346 TREE_VEC_ELT (label_vec, i) = TREE_VEC_ELT (label_vec, len - 1);
1347 TREE_VEC_ELT (label_vec, len - 1) = default_case;
1348 break;
1349 }
1350 }
1351 }
1352
1353 qsort (&TREE_VEC_ELT (label_vec, 0), len - 1, sizeof (tree),
1354 compare_case_labels);
1355 }
1356
1357 /* Gimplify a SWITCH_EXPR, and collect a TREE_VEC of the labels it can
1358 branch to. */
1359
1360 static enum gimplify_status
1361 gimplify_switch_expr (tree *expr_p, tree *pre_p)
1362 {
1363 tree switch_expr = *expr_p;
1364 enum gimplify_status ret;
1365
1366 ret = gimplify_expr (&SWITCH_COND (switch_expr), pre_p, NULL,
1367 is_gimple_val, fb_rvalue);
1368
1369 if (SWITCH_BODY (switch_expr))
1370 {
1371 VEC(tree,heap) *labels, *saved_labels;
1372 tree label_vec, default_case = NULL_TREE;
1373 size_t i, len;
1374
1375 /* If someone can be bothered to fill in the labels, they can
1376 be bothered to null out the body too. */
1377 gcc_assert (!SWITCH_LABELS (switch_expr));
1378
1379 saved_labels = gimplify_ctxp->case_labels;
1380 gimplify_ctxp->case_labels = VEC_alloc (tree, heap, 8);
1381
1382 gimplify_to_stmt_list (&SWITCH_BODY (switch_expr));
1383
1384 labels = gimplify_ctxp->case_labels;
1385 gimplify_ctxp->case_labels = saved_labels;
1386
1387 i = 0;
1388 while (i < VEC_length (tree, labels))
1389 {
1390 tree elt = VEC_index (tree, labels, i);
1391 tree low = CASE_LOW (elt);
1392 bool remove_element = FALSE;
1393
1394 if (low)
1395 {
1396 /* Discard empty ranges. */
1397 tree high = CASE_HIGH (elt);
1398 if (high && INT_CST_LT (high, low))
1399 remove_element = TRUE;
1400 }
1401 else
1402 {
1403 /* The default case must be the last label in the list. */
1404 gcc_assert (!default_case);
1405 default_case = elt;
1406 remove_element = TRUE;
1407 }
1408
1409 if (remove_element)
1410 VEC_ordered_remove (tree, labels, i);
1411 else
1412 i++;
1413 }
1414 len = i;
1415
1416 label_vec = make_tree_vec (len + 1);
1417 SWITCH_LABELS (*expr_p) = label_vec;
1418 append_to_statement_list (switch_expr, pre_p);
1419
1420 if (! default_case)
1421 {
1422 /* If the switch has no default label, add one, so that we jump
1423 around the switch body. */
1424 default_case = build3 (CASE_LABEL_EXPR, void_type_node, NULL_TREE,
1425 NULL_TREE, create_artificial_label ());
1426 append_to_statement_list (SWITCH_BODY (switch_expr), pre_p);
1427 *expr_p = build1 (LABEL_EXPR, void_type_node,
1428 CASE_LABEL (default_case));
1429 }
1430 else
1431 *expr_p = SWITCH_BODY (switch_expr);
1432
1433 for (i = 0; i < len; ++i)
1434 TREE_VEC_ELT (label_vec, i) = VEC_index (tree, labels, i);
1435 TREE_VEC_ELT (label_vec, len) = default_case;
1436
1437 VEC_free (tree, heap, labels);
1438
1439 sort_case_labels (label_vec);
1440
1441 SWITCH_BODY (switch_expr) = NULL;
1442 }
1443 else
1444 gcc_assert (SWITCH_LABELS (switch_expr));
1445
1446 return ret;
1447 }
1448
1449 static enum gimplify_status
1450 gimplify_case_label_expr (tree *expr_p)
1451 {
1452 tree expr = *expr_p;
1453 struct gimplify_ctx *ctxp;
1454
1455 /* Invalid OpenMP programs can play Duff's Device type games with
1456 #pragma omp parallel. At least in the C front end, we don't
1457 detect such invalid branches until after gimplification. */
1458 for (ctxp = gimplify_ctxp; ; ctxp = ctxp->prev_context)
1459 if (ctxp->case_labels)
1460 break;
1461
1462 VEC_safe_push (tree, heap, ctxp->case_labels, expr);
1463 *expr_p = build1 (LABEL_EXPR, void_type_node, CASE_LABEL (expr));
1464 return GS_ALL_DONE;
1465 }
1466
1467 /* Build a GOTO to the LABEL_DECL pointed to by LABEL_P, building it first
1468 if necessary. */
1469
1470 tree
1471 build_and_jump (tree *label_p)
1472 {
1473 if (label_p == NULL)
1474 /* If there's nowhere to jump, just fall through. */
1475 return NULL_TREE;
1476
1477 if (*label_p == NULL_TREE)
1478 {
1479 tree label = create_artificial_label ();
1480 *label_p = label;
1481 }
1482
1483 return build1 (GOTO_EXPR, void_type_node, *label_p);
1484 }
1485
1486 /* Gimplify an EXIT_EXPR by converting to a GOTO_EXPR inside a COND_EXPR.
1487 This also involves building a label to jump to and communicating it to
1488 gimplify_loop_expr through gimplify_ctxp->exit_label. */
1489
1490 static enum gimplify_status
1491 gimplify_exit_expr (tree *expr_p)
1492 {
1493 tree cond = TREE_OPERAND (*expr_p, 0);
1494 tree expr;
1495
1496 expr = build_and_jump (&gimplify_ctxp->exit_label);
1497 expr = build3 (COND_EXPR, void_type_node, cond, expr, NULL_TREE);
1498 *expr_p = expr;
1499
1500 return GS_OK;
1501 }
1502
1503 /* A helper function to be called via walk_tree. Mark all labels under *TP
1504 as being forced. To be called for DECL_INITIAL of static variables. */
1505
1506 tree
1507 force_labels_r (tree *tp, int *walk_subtrees, void *data ATTRIBUTE_UNUSED)
1508 {
1509 if (TYPE_P (*tp))
1510 *walk_subtrees = 0;
1511 if (TREE_CODE (*tp) == LABEL_DECL)
1512 FORCED_LABEL (*tp) = 1;
1513
1514 return NULL_TREE;
1515 }
1516
1517 /* *EXPR_P is a COMPONENT_REF being used as an rvalue. If its type is
1518 different from its canonical type, wrap the whole thing inside a
1519 NOP_EXPR and force the type of the COMPONENT_REF to be the canonical
1520 type.
1521
1522 The canonical type of a COMPONENT_REF is the type of the field being
1523 referenced--unless the field is a bit-field which can be read directly
1524 in a smaller mode, in which case the canonical type is the
1525 sign-appropriate type corresponding to that mode. */
1526
1527 static void
1528 canonicalize_component_ref (tree *expr_p)
1529 {
1530 tree expr = *expr_p;
1531 tree type;
1532
1533 gcc_assert (TREE_CODE (expr) == COMPONENT_REF);
1534
1535 if (INTEGRAL_TYPE_P (TREE_TYPE (expr)))
1536 type = TREE_TYPE (get_unwidened (expr, NULL_TREE));
1537 else
1538 type = TREE_TYPE (TREE_OPERAND (expr, 1));
1539
1540 if (TREE_TYPE (expr) != type)
1541 {
1542 tree old_type = TREE_TYPE (expr);
1543
1544 /* Set the type of the COMPONENT_REF to the underlying type. */
1545 TREE_TYPE (expr) = type;
1546
1547 /* And wrap the whole thing inside a NOP_EXPR. */
1548 expr = build1 (NOP_EXPR, old_type, expr);
1549
1550 *expr_p = expr;
1551 }
1552 }
1553
1554 /* If a NOP conversion is changing a pointer to array of foo to a pointer
1555 to foo, embed that change in the ADDR_EXPR by converting
1556 T array[U];
1557 (T *)&array
1558 ==>
1559 &array[L]
1560 where L is the lower bound. For simplicity, only do this for constant
1561 lower bound. */
1562
1563 static void
1564 canonicalize_addr_expr (tree *expr_p)
1565 {
1566 tree expr = *expr_p;
1567 tree ctype = TREE_TYPE (expr);
1568 tree addr_expr = TREE_OPERAND (expr, 0);
1569 tree atype = TREE_TYPE (addr_expr);
1570 tree dctype, datype, ddatype, otype, obj_expr;
1571
1572 /* Both cast and addr_expr types should be pointers. */
1573 if (!POINTER_TYPE_P (ctype) || !POINTER_TYPE_P (atype))
1574 return;
1575
1576 /* The addr_expr type should be a pointer to an array. */
1577 datype = TREE_TYPE (atype);
1578 if (TREE_CODE (datype) != ARRAY_TYPE)
1579 return;
1580
1581 /* Both cast and addr_expr types should address the same object type. */
1582 dctype = TREE_TYPE (ctype);
1583 ddatype = TREE_TYPE (datype);
1584 if (!lang_hooks.types_compatible_p (ddatype, dctype))
1585 return;
1586
1587 /* The addr_expr and the object type should match. */
1588 obj_expr = TREE_OPERAND (addr_expr, 0);
1589 otype = TREE_TYPE (obj_expr);
1590 if (!lang_hooks.types_compatible_p (otype, datype))
1591 return;
1592
1593 /* The lower bound and element sizes must be constant. */
1594 if (!TYPE_SIZE_UNIT (dctype)
1595 || TREE_CODE (TYPE_SIZE_UNIT (dctype)) != INTEGER_CST
1596 || !TYPE_DOMAIN (datype) || !TYPE_MIN_VALUE (TYPE_DOMAIN (datype))
1597 || TREE_CODE (TYPE_MIN_VALUE (TYPE_DOMAIN (datype))) != INTEGER_CST)
1598 return;
1599
1600 /* All checks succeeded. Build a new node to merge the cast. */
1601 *expr_p = build4 (ARRAY_REF, dctype, obj_expr,
1602 TYPE_MIN_VALUE (TYPE_DOMAIN (datype)),
1603 TYPE_MIN_VALUE (TYPE_DOMAIN (datype)),
1604 size_binop (EXACT_DIV_EXPR, TYPE_SIZE_UNIT (dctype),
1605 size_int (TYPE_ALIGN_UNIT (dctype))));
1606 *expr_p = build1 (ADDR_EXPR, ctype, *expr_p);
1607 }
1608
1609 /* *EXPR_P is a NOP_EXPR or CONVERT_EXPR. Remove it and/or other conversions
1610 underneath as appropriate. */
1611
1612 static enum gimplify_status
1613 gimplify_conversion (tree *expr_p)
1614 {
1615 gcc_assert (TREE_CODE (*expr_p) == NOP_EXPR
1616 || TREE_CODE (*expr_p) == CONVERT_EXPR);
1617
1618 /* Then strip away all but the outermost conversion. */
1619 STRIP_SIGN_NOPS (TREE_OPERAND (*expr_p, 0));
1620
1621 /* And remove the outermost conversion if it's useless. */
1622 if (tree_ssa_useless_type_conversion (*expr_p))
1623 *expr_p = TREE_OPERAND (*expr_p, 0);
1624
1625 /* If we still have a conversion at the toplevel,
1626 then canonicalize some constructs. */
1627 if (TREE_CODE (*expr_p) == NOP_EXPR || TREE_CODE (*expr_p) == CONVERT_EXPR)
1628 {
1629 tree sub = TREE_OPERAND (*expr_p, 0);
1630
1631 /* If a NOP conversion is changing the type of a COMPONENT_REF
1632 expression, then canonicalize its type now in order to expose more
1633 redundant conversions. */
1634 if (TREE_CODE (sub) == COMPONENT_REF)
1635 canonicalize_component_ref (&TREE_OPERAND (*expr_p, 0));
1636
1637 /* If a NOP conversion is changing a pointer to array of foo
1638 to a pointer to foo, embed that change in the ADDR_EXPR. */
1639 else if (TREE_CODE (sub) == ADDR_EXPR)
1640 canonicalize_addr_expr (expr_p);
1641 }
1642
1643 return GS_OK;
1644 }
1645
1646 /* Gimplify a VAR_DECL or PARM_DECL. Returns GS_OK if we expanded a
1647 DECL_VALUE_EXPR, and it's worth re-examining things. */
1648
1649 static enum gimplify_status
1650 gimplify_var_or_parm_decl (tree *expr_p)
1651 {
1652 tree decl = *expr_p;
1653
1654 /* ??? If this is a local variable, and it has not been seen in any
1655 outer BIND_EXPR, then it's probably the result of a duplicate
1656 declaration, for which we've already issued an error. It would
1657 be really nice if the front end wouldn't leak these at all.
1658 Currently the only known culprit is C++ destructors, as seen
1659 in g++.old-deja/g++.jason/binding.C. */
1660 if (TREE_CODE (decl) == VAR_DECL
1661 && !DECL_SEEN_IN_BIND_EXPR_P (decl)
1662 && !TREE_STATIC (decl) && !DECL_EXTERNAL (decl)
1663 && decl_function_context (decl) == current_function_decl)
1664 {
1665 gcc_assert (errorcount || sorrycount);
1666 return GS_ERROR;
1667 }
1668
1669 /* When within an OpenMP context, notice uses of variables. */
1670 if (gimplify_omp_ctxp && omp_notice_variable (gimplify_omp_ctxp, decl, true))
1671 return GS_ALL_DONE;
1672
1673 /* If the decl is an alias for another expression, substitute it now. */
1674 if (DECL_HAS_VALUE_EXPR_P (decl))
1675 {
1676 *expr_p = unshare_expr (DECL_VALUE_EXPR (decl));
1677 return GS_OK;
1678 }
1679
1680 return GS_ALL_DONE;
1681 }
1682
1683
1684 /* Gimplify the COMPONENT_REF, ARRAY_REF, REALPART_EXPR or IMAGPART_EXPR
1685 node pointed to by EXPR_P.
1686
1687 compound_lval
1688 : min_lval '[' val ']'
1689 | min_lval '.' ID
1690 | compound_lval '[' val ']'
1691 | compound_lval '.' ID
1692
1693 This is not part of the original SIMPLE definition, which separates
1694 array and member references, but it seems reasonable to handle them
1695 together. Also, this way we don't run into problems with union
1696 aliasing; gcc requires that for accesses through a union to alias, the
1697 union reference must be explicit, which was not always the case when we
1698 were splitting up array and member refs.
1699
1700 PRE_P points to the list where side effects that must happen before
1701 *EXPR_P should be stored.
1702
1703 POST_P points to the list where side effects that must happen after
1704 *EXPR_P should be stored. */
1705
1706 static enum gimplify_status
1707 gimplify_compound_lval (tree *expr_p, tree *pre_p,
1708 tree *post_p, fallback_t fallback)
1709 {
1710 tree *p;
1711 VEC(tree,heap) *stack;
1712 enum gimplify_status ret = GS_OK, tret;
1713 int i;
1714
1715 /* Create a stack of the subexpressions so later we can walk them in
1716 order from inner to outer. */
1717 stack = VEC_alloc (tree, heap, 10);
1718
1719 /* We can handle anything that get_inner_reference can deal with. */
1720 for (p = expr_p; ; p = &TREE_OPERAND (*p, 0))
1721 {
1722 restart:
1723 /* Fold INDIRECT_REFs now to turn them into ARRAY_REFs. */
1724 if (TREE_CODE (*p) == INDIRECT_REF)
1725 *p = fold_indirect_ref (*p);
1726
1727 if (handled_component_p (*p))
1728 ;
1729 /* Expand DECL_VALUE_EXPR now. In some cases that may expose
1730 additional COMPONENT_REFs. */
1731 else if ((TREE_CODE (*p) == VAR_DECL || TREE_CODE (*p) == PARM_DECL)
1732 && gimplify_var_or_parm_decl (p) == GS_OK)
1733 goto restart;
1734 else
1735 break;
1736
1737 VEC_safe_push (tree, heap, stack, *p);
1738 }
1739
1740 gcc_assert (VEC_length (tree, stack));
1741
1742 /* Now STACK is a stack of pointers to all the refs we've walked through
1743 and P points to the innermost expression.
1744
1745 Java requires that we elaborated nodes in source order. That
1746 means we must gimplify the inner expression followed by each of
1747 the indices, in order. But we can't gimplify the inner
1748 expression until we deal with any variable bounds, sizes, or
1749 positions in order to deal with PLACEHOLDER_EXPRs.
1750
1751 So we do this in three steps. First we deal with the annotations
1752 for any variables in the components, then we gimplify the base,
1753 then we gimplify any indices, from left to right. */
1754 for (i = VEC_length (tree, stack) - 1; i >= 0; i--)
1755 {
1756 tree t = VEC_index (tree, stack, i);
1757
1758 if (TREE_CODE (t) == ARRAY_REF || TREE_CODE (t) == ARRAY_RANGE_REF)
1759 {
1760 /* Gimplify the low bound and element type size and put them into
1761 the ARRAY_REF. If these values are set, they have already been
1762 gimplified. */
1763 if (!TREE_OPERAND (t, 2))
1764 {
1765 tree low = unshare_expr (array_ref_low_bound (t));
1766 if (!is_gimple_min_invariant (low))
1767 {
1768 TREE_OPERAND (t, 2) = low;
1769 tret = gimplify_expr (&TREE_OPERAND (t, 2), pre_p, post_p,
1770 is_gimple_formal_tmp_reg, fb_rvalue);
1771 ret = MIN (ret, tret);
1772 }
1773 }
1774
1775 if (!TREE_OPERAND (t, 3))
1776 {
1777 tree elmt_type = TREE_TYPE (TREE_TYPE (TREE_OPERAND (t, 0)));
1778 tree elmt_size = unshare_expr (array_ref_element_size (t));
1779 tree factor = size_int (TYPE_ALIGN_UNIT (elmt_type));
1780
1781 /* Divide the element size by the alignment of the element
1782 type (above). */
1783 elmt_size = size_binop (EXACT_DIV_EXPR, elmt_size, factor);
1784
1785 if (!is_gimple_min_invariant (elmt_size))
1786 {
1787 TREE_OPERAND (t, 3) = elmt_size;
1788 tret = gimplify_expr (&TREE_OPERAND (t, 3), pre_p, post_p,
1789 is_gimple_formal_tmp_reg, fb_rvalue);
1790 ret = MIN (ret, tret);
1791 }
1792 }
1793 }
1794 else if (TREE_CODE (t) == COMPONENT_REF)
1795 {
1796 /* Set the field offset into T and gimplify it. */
1797 if (!TREE_OPERAND (t, 2))
1798 {
1799 tree offset = unshare_expr (component_ref_field_offset (t));
1800 tree field = TREE_OPERAND (t, 1);
1801 tree factor
1802 = size_int (DECL_OFFSET_ALIGN (field) / BITS_PER_UNIT);
1803
1804 /* Divide the offset by its alignment. */
1805 offset = size_binop (EXACT_DIV_EXPR, offset, factor);
1806
1807 if (!is_gimple_min_invariant (offset))
1808 {
1809 TREE_OPERAND (t, 2) = offset;
1810 tret = gimplify_expr (&TREE_OPERAND (t, 2), pre_p, post_p,
1811 is_gimple_formal_tmp_reg, fb_rvalue);
1812 ret = MIN (ret, tret);
1813 }
1814 }
1815 }
1816 }
1817
1818 /* Step 2 is to gimplify the base expression. Make sure lvalue is set
1819 so as to match the min_lval predicate. Failure to do so may result
1820 in the creation of large aggregate temporaries. */
1821 tret = gimplify_expr (p, pre_p, post_p, is_gimple_min_lval,
1822 fallback | fb_lvalue);
1823 ret = MIN (ret, tret);
1824
1825 /* And finally, the indices and operands to BIT_FIELD_REF. During this
1826 loop we also remove any useless conversions. */
1827 for (; VEC_length (tree, stack) > 0; )
1828 {
1829 tree t = VEC_pop (tree, stack);
1830
1831 if (TREE_CODE (t) == ARRAY_REF || TREE_CODE (t) == ARRAY_RANGE_REF)
1832 {
1833 /* Gimplify the dimension.
1834 Temporary fix for gcc.c-torture/execute/20040313-1.c.
1835 Gimplify non-constant array indices into a temporary
1836 variable.
1837 FIXME - The real fix is to gimplify post-modify
1838 expressions into a minimal gimple lvalue. However, that
1839 exposes bugs in alias analysis. The alias analyzer does
1840 not handle &PTR->FIELD very well. Will fix after the
1841 branch is merged into mainline (dnovillo 2004-05-03). */
1842 if (!is_gimple_min_invariant (TREE_OPERAND (t, 1)))
1843 {
1844 tret = gimplify_expr (&TREE_OPERAND (t, 1), pre_p, post_p,
1845 is_gimple_formal_tmp_reg, fb_rvalue);
1846 ret = MIN (ret, tret);
1847 }
1848 }
1849 else if (TREE_CODE (t) == BIT_FIELD_REF)
1850 {
1851 tret = gimplify_expr (&TREE_OPERAND (t, 1), pre_p, post_p,
1852 is_gimple_val, fb_rvalue);
1853 ret = MIN (ret, tret);
1854 tret = gimplify_expr (&TREE_OPERAND (t, 2), pre_p, post_p,
1855 is_gimple_val, fb_rvalue);
1856 ret = MIN (ret, tret);
1857 }
1858
1859 STRIP_USELESS_TYPE_CONVERSION (TREE_OPERAND (t, 0));
1860
1861 /* The innermost expression P may have originally had TREE_SIDE_EFFECTS
1862 set which would have caused all the outer expressions in EXPR_P
1863 leading to P to also have had TREE_SIDE_EFFECTS set. */
1864 recalculate_side_effects (t);
1865 }
1866
1867 tret = gimplify_expr (p, pre_p, post_p, is_gimple_min_lval, fallback);
1868 ret = MIN (ret, tret);
1869
1870 /* If the outermost expression is a COMPONENT_REF, canonicalize its type. */
1871 if ((fallback & fb_rvalue) && TREE_CODE (*expr_p) == COMPONENT_REF)
1872 {
1873 canonicalize_component_ref (expr_p);
1874 ret = MIN (ret, GS_OK);
1875 }
1876
1877 VEC_free (tree, heap, stack);
1878
1879 return ret;
1880 }
1881
1882 /* Gimplify the self modifying expression pointed to by EXPR_P
1883 (++, --, +=, -=).
1884
1885 PRE_P points to the list where side effects that must happen before
1886 *EXPR_P should be stored.
1887
1888 POST_P points to the list where side effects that must happen after
1889 *EXPR_P should be stored.
1890
1891 WANT_VALUE is nonzero iff we want to use the value of this expression
1892 in another expression. */
1893
1894 static enum gimplify_status
1895 gimplify_self_mod_expr (tree *expr_p, tree *pre_p, tree *post_p,
1896 bool want_value)
1897 {
1898 enum tree_code code;
1899 tree lhs, lvalue, rhs, t1;
1900 bool postfix;
1901 enum tree_code arith_code;
1902 enum gimplify_status ret;
1903
1904 code = TREE_CODE (*expr_p);
1905
1906 gcc_assert (code == POSTINCREMENT_EXPR || code == POSTDECREMENT_EXPR
1907 || code == PREINCREMENT_EXPR || code == PREDECREMENT_EXPR);
1908
1909 /* Prefix or postfix? */
1910 if (code == POSTINCREMENT_EXPR || code == POSTDECREMENT_EXPR)
1911 /* Faster to treat as prefix if result is not used. */
1912 postfix = want_value;
1913 else
1914 postfix = false;
1915
1916 /* Add or subtract? */
1917 if (code == PREINCREMENT_EXPR || code == POSTINCREMENT_EXPR)
1918 arith_code = PLUS_EXPR;
1919 else
1920 arith_code = MINUS_EXPR;
1921
1922 /* Gimplify the LHS into a GIMPLE lvalue. */
1923 lvalue = TREE_OPERAND (*expr_p, 0);
1924 ret = gimplify_expr (&lvalue, pre_p, post_p, is_gimple_lvalue, fb_lvalue);
1925 if (ret == GS_ERROR)
1926 return ret;
1927
1928 /* Extract the operands to the arithmetic operation. */
1929 lhs = lvalue;
1930 rhs = TREE_OPERAND (*expr_p, 1);
1931
1932 /* For postfix operator, we evaluate the LHS to an rvalue and then use
1933 that as the result value and in the postqueue operation. */
1934 if (postfix)
1935 {
1936 ret = gimplify_expr (&lhs, pre_p, post_p, is_gimple_val, fb_rvalue);
1937 if (ret == GS_ERROR)
1938 return ret;
1939 }
1940
1941 t1 = build2 (arith_code, TREE_TYPE (*expr_p), lhs, rhs);
1942 t1 = build2 (MODIFY_EXPR, TREE_TYPE (lvalue), lvalue, t1);
1943
1944 if (postfix)
1945 {
1946 gimplify_and_add (t1, post_p);
1947 *expr_p = lhs;
1948 return GS_ALL_DONE;
1949 }
1950 else
1951 {
1952 *expr_p = t1;
1953 return GS_OK;
1954 }
1955 }
1956
1957 /* If *EXPR_P has a variable sized type, wrap it in a WITH_SIZE_EXPR. */
1958
1959 static void
1960 maybe_with_size_expr (tree *expr_p)
1961 {
1962 tree expr = *expr_p;
1963 tree type = TREE_TYPE (expr);
1964 tree size;
1965
1966 /* If we've already wrapped this or the type is error_mark_node, we can't do
1967 anything. */
1968 if (TREE_CODE (expr) == WITH_SIZE_EXPR
1969 || type == error_mark_node)
1970 return;
1971
1972 /* If the size isn't known or is a constant, we have nothing to do. */
1973 size = TYPE_SIZE_UNIT (type);
1974 if (!size || TREE_CODE (size) == INTEGER_CST)
1975 return;
1976
1977 /* Otherwise, make a WITH_SIZE_EXPR. */
1978 size = unshare_expr (size);
1979 size = SUBSTITUTE_PLACEHOLDER_IN_EXPR (size, expr);
1980 *expr_p = build2 (WITH_SIZE_EXPR, type, expr, size);
1981 }
1982
1983 /* Subroutine of gimplify_call_expr: Gimplify a single argument. */
1984
1985 static enum gimplify_status
1986 gimplify_arg (tree *expr_p, tree *pre_p)
1987 {
1988 bool (*test) (tree);
1989 fallback_t fb;
1990
1991 /* In general, we allow lvalues for function arguments to avoid
1992 extra overhead of copying large aggregates out of even larger
1993 aggregates into temporaries only to copy the temporaries to
1994 the argument list. Make optimizers happy by pulling out to
1995 temporaries those types that fit in registers. */
1996 if (is_gimple_reg_type (TREE_TYPE (*expr_p)))
1997 test = is_gimple_val, fb = fb_rvalue;
1998 else
1999 test = is_gimple_lvalue, fb = fb_either;
2000
2001 /* If this is a variable sized type, we must remember the size. */
2002 maybe_with_size_expr (expr_p);
2003
2004 /* There is a sequence point before a function call. Side effects in
2005 the argument list must occur before the actual call. So, when
2006 gimplifying arguments, force gimplify_expr to use an internal
2007 post queue which is then appended to the end of PRE_P. */
2008 return gimplify_expr (expr_p, pre_p, NULL, test, fb);
2009 }
2010
2011 /* Gimplify the CALL_EXPR node pointed to by EXPR_P. PRE_P points to the
2012 list where side effects that must happen before *EXPR_P should be stored.
2013 WANT_VALUE is true if the result of the call is desired. */
2014
2015 static enum gimplify_status
2016 gimplify_call_expr (tree *expr_p, tree *pre_p, bool want_value)
2017 {
2018 tree decl;
2019 tree arglist;
2020 enum gimplify_status ret;
2021
2022 gcc_assert (TREE_CODE (*expr_p) == CALL_EXPR);
2023
2024 /* For reliable diagnostics during inlining, it is necessary that
2025 every call_expr be annotated with file and line. */
2026 if (! EXPR_HAS_LOCATION (*expr_p))
2027 SET_EXPR_LOCATION (*expr_p, input_location);
2028
2029 /* This may be a call to a builtin function.
2030
2031 Builtin function calls may be transformed into different
2032 (and more efficient) builtin function calls under certain
2033 circumstances. Unfortunately, gimplification can muck things
2034 up enough that the builtin expanders are not aware that certain
2035 transformations are still valid.
2036
2037 So we attempt transformation/gimplification of the call before
2038 we gimplify the CALL_EXPR. At this time we do not manage to
2039 transform all calls in the same manner as the expanders do, but
2040 we do transform most of them. */
2041 decl = get_callee_fndecl (*expr_p);
2042 if (decl && DECL_BUILT_IN (decl))
2043 {
2044 tree arglist = TREE_OPERAND (*expr_p, 1);
2045 tree new = fold_builtin (decl, arglist, !want_value);
2046
2047 if (new && new != *expr_p)
2048 {
2049 /* There was a transformation of this call which computes the
2050 same value, but in a more efficient way. Return and try
2051 again. */
2052 *expr_p = new;
2053 return GS_OK;
2054 }
2055
2056 if (DECL_BUILT_IN_CLASS (decl) == BUILT_IN_NORMAL
2057 && DECL_FUNCTION_CODE (decl) == BUILT_IN_VA_START)
2058 {
2059 if (!arglist || !TREE_CHAIN (arglist))
2060 {
2061 error ("too few arguments to function %<va_start%>");
2062 *expr_p = build_empty_stmt ();
2063 return GS_OK;
2064 }
2065
2066 if (fold_builtin_next_arg (TREE_CHAIN (arglist)))
2067 {
2068 *expr_p = build_empty_stmt ();
2069 return GS_OK;
2070 }
2071 /* Avoid gimplifying the second argument to va_start, which needs
2072 to be the plain PARM_DECL. */
2073 return gimplify_arg (&TREE_VALUE (TREE_OPERAND (*expr_p, 1)), pre_p);
2074 }
2075 }
2076
2077 /* There is a sequence point before the call, so any side effects in
2078 the calling expression must occur before the actual call. Force
2079 gimplify_expr to use an internal post queue. */
2080 ret = gimplify_expr (&TREE_OPERAND (*expr_p, 0), pre_p, NULL,
2081 is_gimple_call_addr, fb_rvalue);
2082
2083 if (PUSH_ARGS_REVERSED)
2084 TREE_OPERAND (*expr_p, 1) = nreverse (TREE_OPERAND (*expr_p, 1));
2085 for (arglist = TREE_OPERAND (*expr_p, 1); arglist;
2086 arglist = TREE_CHAIN (arglist))
2087 {
2088 enum gimplify_status t;
2089
2090 t = gimplify_arg (&TREE_VALUE (arglist), pre_p);
2091
2092 if (t == GS_ERROR)
2093 ret = GS_ERROR;
2094 }
2095 if (PUSH_ARGS_REVERSED)
2096 TREE_OPERAND (*expr_p, 1) = nreverse (TREE_OPERAND (*expr_p, 1));
2097
2098 /* Try this again in case gimplification exposed something. */
2099 if (ret != GS_ERROR)
2100 {
2101 decl = get_callee_fndecl (*expr_p);
2102 if (decl && DECL_BUILT_IN (decl))
2103 {
2104 tree arglist = TREE_OPERAND (*expr_p, 1);
2105 tree new = fold_builtin (decl, arglist, !want_value);
2106
2107 if (new && new != *expr_p)
2108 {
2109 /* There was a transformation of this call which computes the
2110 same value, but in a more efficient way. Return and try
2111 again. */
2112 *expr_p = new;
2113 return GS_OK;
2114 }
2115 }
2116 }
2117
2118 /* If the function is "const" or "pure", then clear TREE_SIDE_EFFECTS on its
2119 decl. This allows us to eliminate redundant or useless
2120 calls to "const" functions. */
2121 if (TREE_CODE (*expr_p) == CALL_EXPR
2122 && (call_expr_flags (*expr_p) & (ECF_CONST | ECF_PURE)))
2123 TREE_SIDE_EFFECTS (*expr_p) = 0;
2124
2125 return ret;
2126 }
2127
2128 /* Handle shortcut semantics in the predicate operand of a COND_EXPR by
2129 rewriting it into multiple COND_EXPRs, and possibly GOTO_EXPRs.
2130
2131 TRUE_LABEL_P and FALSE_LABEL_P point to the labels to jump to if the
2132 condition is true or false, respectively. If null, we should generate
2133 our own to skip over the evaluation of this specific expression.
2134
2135 This function is the tree equivalent of do_jump.
2136
2137 shortcut_cond_r should only be called by shortcut_cond_expr. */
2138
2139 static tree
2140 shortcut_cond_r (tree pred, tree *true_label_p, tree *false_label_p)
2141 {
2142 tree local_label = NULL_TREE;
2143 tree t, expr = NULL;
2144
2145 /* OK, it's not a simple case; we need to pull apart the COND_EXPR to
2146 retain the shortcut semantics. Just insert the gotos here;
2147 shortcut_cond_expr will append the real blocks later. */
2148 if (TREE_CODE (pred) == TRUTH_ANDIF_EXPR)
2149 {
2150 /* Turn if (a && b) into
2151
2152 if (a); else goto no;
2153 if (b) goto yes; else goto no;
2154 (no:) */
2155
2156 if (false_label_p == NULL)
2157 false_label_p = &local_label;
2158
2159 t = shortcut_cond_r (TREE_OPERAND (pred, 0), NULL, false_label_p);
2160 append_to_statement_list (t, &expr);
2161
2162 t = shortcut_cond_r (TREE_OPERAND (pred, 1), true_label_p,
2163 false_label_p);
2164 append_to_statement_list (t, &expr);
2165 }
2166 else if (TREE_CODE (pred) == TRUTH_ORIF_EXPR)
2167 {
2168 /* Turn if (a || b) into
2169
2170 if (a) goto yes;
2171 if (b) goto yes; else goto no;
2172 (yes:) */
2173
2174 if (true_label_p == NULL)
2175 true_label_p = &local_label;
2176
2177 t = shortcut_cond_r (TREE_OPERAND (pred, 0), true_label_p, NULL);
2178 append_to_statement_list (t, &expr);
2179
2180 t = shortcut_cond_r (TREE_OPERAND (pred, 1), true_label_p,
2181 false_label_p);
2182 append_to_statement_list (t, &expr);
2183 }
2184 else if (TREE_CODE (pred) == COND_EXPR)
2185 {
2186 /* As long as we're messing with gotos, turn if (a ? b : c) into
2187 if (a)
2188 if (b) goto yes; else goto no;
2189 else
2190 if (c) goto yes; else goto no; */
2191 expr = build3 (COND_EXPR, void_type_node, TREE_OPERAND (pred, 0),
2192 shortcut_cond_r (TREE_OPERAND (pred, 1), true_label_p,
2193 false_label_p),
2194 shortcut_cond_r (TREE_OPERAND (pred, 2), true_label_p,
2195 false_label_p));
2196 }
2197 else
2198 {
2199 expr = build3 (COND_EXPR, void_type_node, pred,
2200 build_and_jump (true_label_p),
2201 build_and_jump (false_label_p));
2202 }
2203
2204 if (local_label)
2205 {
2206 t = build1 (LABEL_EXPR, void_type_node, local_label);
2207 append_to_statement_list (t, &expr);
2208 }
2209
2210 return expr;
2211 }
2212
2213 static tree
2214 shortcut_cond_expr (tree expr)
2215 {
2216 tree pred = TREE_OPERAND (expr, 0);
2217 tree then_ = TREE_OPERAND (expr, 1);
2218 tree else_ = TREE_OPERAND (expr, 2);
2219 tree true_label, false_label, end_label, t;
2220 tree *true_label_p;
2221 tree *false_label_p;
2222 bool emit_end, emit_false, jump_over_else;
2223 bool then_se = then_ && TREE_SIDE_EFFECTS (then_);
2224 bool else_se = else_ && TREE_SIDE_EFFECTS (else_);
2225
2226 /* First do simple transformations. */
2227 if (!else_se)
2228 {
2229 /* If there is no 'else', turn (a && b) into if (a) if (b). */
2230 while (TREE_CODE (pred) == TRUTH_ANDIF_EXPR)
2231 {
2232 TREE_OPERAND (expr, 0) = TREE_OPERAND (pred, 1);
2233 then_ = shortcut_cond_expr (expr);
2234 then_se = then_ && TREE_SIDE_EFFECTS (then_);
2235 pred = TREE_OPERAND (pred, 0);
2236 expr = build3 (COND_EXPR, void_type_node, pred, then_, NULL_TREE);
2237 }
2238 }
2239 if (!then_se)
2240 {
2241 /* If there is no 'then', turn
2242 if (a || b); else d
2243 into
2244 if (a); else if (b); else d. */
2245 while (TREE_CODE (pred) == TRUTH_ORIF_EXPR)
2246 {
2247 TREE_OPERAND (expr, 0) = TREE_OPERAND (pred, 1);
2248 else_ = shortcut_cond_expr (expr);
2249 else_se = else_ && TREE_SIDE_EFFECTS (else_);
2250 pred = TREE_OPERAND (pred, 0);
2251 expr = build3 (COND_EXPR, void_type_node, pred, NULL_TREE, else_);
2252 }
2253 }
2254
2255 /* If we're done, great. */
2256 if (TREE_CODE (pred) != TRUTH_ANDIF_EXPR
2257 && TREE_CODE (pred) != TRUTH_ORIF_EXPR)
2258 return expr;
2259
2260 /* Otherwise we need to mess with gotos. Change
2261 if (a) c; else d;
2262 to
2263 if (a); else goto no;
2264 c; goto end;
2265 no: d; end:
2266 and recursively gimplify the condition. */
2267
2268 true_label = false_label = end_label = NULL_TREE;
2269
2270 /* If our arms just jump somewhere, hijack those labels so we don't
2271 generate jumps to jumps. */
2272
2273 if (then_
2274 && TREE_CODE (then_) == GOTO_EXPR
2275 && TREE_CODE (GOTO_DESTINATION (then_)) == LABEL_DECL)
2276 {
2277 true_label = GOTO_DESTINATION (then_);
2278 then_ = NULL;
2279 then_se = false;
2280 }
2281
2282 if (else_
2283 && TREE_CODE (else_) == GOTO_EXPR
2284 && TREE_CODE (GOTO_DESTINATION (else_)) == LABEL_DECL)
2285 {
2286 false_label = GOTO_DESTINATION (else_);
2287 else_ = NULL;
2288 else_se = false;
2289 }
2290
2291 /* If we aren't hijacking a label for the 'then' branch, it falls through. */
2292 if (true_label)
2293 true_label_p = &true_label;
2294 else
2295 true_label_p = NULL;
2296
2297 /* The 'else' branch also needs a label if it contains interesting code. */
2298 if (false_label || else_se)
2299 false_label_p = &false_label;
2300 else
2301 false_label_p = NULL;
2302
2303 /* If there was nothing else in our arms, just forward the label(s). */
2304 if (!then_se && !else_se)
2305 return shortcut_cond_r (pred, true_label_p, false_label_p);
2306
2307 /* If our last subexpression already has a terminal label, reuse it. */
2308 if (else_se)
2309 expr = expr_last (else_);
2310 else if (then_se)
2311 expr = expr_last (then_);
2312 else
2313 expr = NULL;
2314 if (expr && TREE_CODE (expr) == LABEL_EXPR)
2315 end_label = LABEL_EXPR_LABEL (expr);
2316
2317 /* If we don't care about jumping to the 'else' branch, jump to the end
2318 if the condition is false. */
2319 if (!false_label_p)
2320 false_label_p = &end_label;
2321
2322 /* We only want to emit these labels if we aren't hijacking them. */
2323 emit_end = (end_label == NULL_TREE);
2324 emit_false = (false_label == NULL_TREE);
2325
2326 /* We only emit the jump over the else clause if we have to--if the
2327 then clause may fall through. Otherwise we can wind up with a
2328 useless jump and a useless label at the end of gimplified code,
2329 which will cause us to think that this conditional as a whole
2330 falls through even if it doesn't. If we then inline a function
2331 which ends with such a condition, that can cause us to issue an
2332 inappropriate warning about control reaching the end of a
2333 non-void function. */
2334 jump_over_else = block_may_fallthru (then_);
2335
2336 pred = shortcut_cond_r (pred, true_label_p, false_label_p);
2337
2338 expr = NULL;
2339 append_to_statement_list (pred, &expr);
2340
2341 append_to_statement_list (then_, &expr);
2342 if (else_se)
2343 {
2344 if (jump_over_else)
2345 {
2346 t = build_and_jump (&end_label);
2347 append_to_statement_list (t, &expr);
2348 }
2349 if (emit_false)
2350 {
2351 t = build1 (LABEL_EXPR, void_type_node, false_label);
2352 append_to_statement_list (t, &expr);
2353 }
2354 append_to_statement_list (else_, &expr);
2355 }
2356 if (emit_end && end_label)
2357 {
2358 t = build1 (LABEL_EXPR, void_type_node, end_label);
2359 append_to_statement_list (t, &expr);
2360 }
2361
2362 return expr;
2363 }
2364
2365 /* EXPR is used in a boolean context; make sure it has BOOLEAN_TYPE. */
2366
2367 tree
2368 gimple_boolify (tree expr)
2369 {
2370 tree type = TREE_TYPE (expr);
2371
2372 if (TREE_CODE (type) == BOOLEAN_TYPE)
2373 return expr;
2374
2375 switch (TREE_CODE (expr))
2376 {
2377 case TRUTH_AND_EXPR:
2378 case TRUTH_OR_EXPR:
2379 case TRUTH_XOR_EXPR:
2380 case TRUTH_ANDIF_EXPR:
2381 case TRUTH_ORIF_EXPR:
2382 /* Also boolify the arguments of truth exprs. */
2383 TREE_OPERAND (expr, 1) = gimple_boolify (TREE_OPERAND (expr, 1));
2384 /* FALLTHRU */
2385
2386 case TRUTH_NOT_EXPR:
2387 TREE_OPERAND (expr, 0) = gimple_boolify (TREE_OPERAND (expr, 0));
2388 /* FALLTHRU */
2389
2390 case EQ_EXPR: case NE_EXPR:
2391 case LE_EXPR: case GE_EXPR: case LT_EXPR: case GT_EXPR:
2392 /* These expressions always produce boolean results. */
2393 TREE_TYPE (expr) = boolean_type_node;
2394 return expr;
2395
2396 default:
2397 /* Other expressions that get here must have boolean values, but
2398 might need to be converted to the appropriate mode. */
2399 return fold_convert (boolean_type_node, expr);
2400 }
2401 }
2402
2403 /* Convert the conditional expression pointed to by EXPR_P '(p) ? a : b;'
2404 into
2405
2406 if (p) if (p)
2407 t1 = a; a;
2408 else or else
2409 t1 = b; b;
2410 t1;
2411
2412 The second form is used when *EXPR_P is of type void.
2413
2414 TARGET is the tree for T1 above.
2415
2416 PRE_P points to the list where side effects that must happen before
2417 *EXPR_P should be stored. */
2418
2419 static enum gimplify_status
2420 gimplify_cond_expr (tree *expr_p, tree *pre_p, fallback_t fallback)
2421 {
2422 tree expr = *expr_p;
2423 tree tmp, tmp2, type;
2424 enum gimplify_status ret;
2425
2426 type = TREE_TYPE (expr);
2427
2428 /* If this COND_EXPR has a value, copy the values into a temporary within
2429 the arms. */
2430 if (! VOID_TYPE_P (type))
2431 {
2432 tree result;
2433
2434 if ((fallback & fb_lvalue) == 0)
2435 {
2436 result = tmp2 = tmp = create_tmp_var (TREE_TYPE (expr), "iftmp");
2437 ret = GS_ALL_DONE;
2438 }
2439 else
2440 {
2441 tree type = build_pointer_type (TREE_TYPE (expr));
2442
2443 if (TREE_TYPE (TREE_OPERAND (expr, 1)) != void_type_node)
2444 TREE_OPERAND (expr, 1) =
2445 build_fold_addr_expr (TREE_OPERAND (expr, 1));
2446
2447 if (TREE_TYPE (TREE_OPERAND (expr, 2)) != void_type_node)
2448 TREE_OPERAND (expr, 2) =
2449 build_fold_addr_expr (TREE_OPERAND (expr, 2));
2450
2451 tmp2 = tmp = create_tmp_var (type, "iftmp");
2452
2453 expr = build3 (COND_EXPR, void_type_node, TREE_OPERAND (expr, 0),
2454 TREE_OPERAND (expr, 1), TREE_OPERAND (expr, 2));
2455
2456 result = build_fold_indirect_ref (tmp);
2457 ret = GS_ALL_DONE;
2458 }
2459
2460 /* Build the then clause, 't1 = a;'. But don't build an assignment
2461 if this branch is void; in C++ it can be, if it's a throw. */
2462 if (TREE_TYPE (TREE_OPERAND (expr, 1)) != void_type_node)
2463 TREE_OPERAND (expr, 1)
2464 = build2 (MODIFY_EXPR, void_type_node, tmp, TREE_OPERAND (expr, 1));
2465
2466 /* Build the else clause, 't1 = b;'. */
2467 if (TREE_TYPE (TREE_OPERAND (expr, 2)) != void_type_node)
2468 TREE_OPERAND (expr, 2)
2469 = build2 (MODIFY_EXPR, void_type_node, tmp2, TREE_OPERAND (expr, 2));
2470
2471 TREE_TYPE (expr) = void_type_node;
2472 recalculate_side_effects (expr);
2473
2474 /* Move the COND_EXPR to the prequeue. */
2475 gimplify_and_add (expr, pre_p);
2476
2477 *expr_p = result;
2478 return ret;
2479 }
2480
2481 /* Make sure the condition has BOOLEAN_TYPE. */
2482 TREE_OPERAND (expr, 0) = gimple_boolify (TREE_OPERAND (expr, 0));
2483
2484 /* Break apart && and || conditions. */
2485 if (TREE_CODE (TREE_OPERAND (expr, 0)) == TRUTH_ANDIF_EXPR
2486 || TREE_CODE (TREE_OPERAND (expr, 0)) == TRUTH_ORIF_EXPR)
2487 {
2488 expr = shortcut_cond_expr (expr);
2489
2490 if (expr != *expr_p)
2491 {
2492 *expr_p = expr;
2493
2494 /* We can't rely on gimplify_expr to re-gimplify the expanded
2495 form properly, as cleanups might cause the target labels to be
2496 wrapped in a TRY_FINALLY_EXPR. To prevent that, we need to
2497 set up a conditional context. */
2498 gimple_push_condition ();
2499 gimplify_stmt (expr_p);
2500 gimple_pop_condition (pre_p);
2501
2502 return GS_ALL_DONE;
2503 }
2504 }
2505
2506 /* Now do the normal gimplification. */
2507 ret = gimplify_expr (&TREE_OPERAND (expr, 0), pre_p, NULL,
2508 is_gimple_condexpr, fb_rvalue);
2509
2510 gimple_push_condition ();
2511
2512 gimplify_to_stmt_list (&TREE_OPERAND (expr, 1));
2513 gimplify_to_stmt_list (&TREE_OPERAND (expr, 2));
2514 recalculate_side_effects (expr);
2515
2516 gimple_pop_condition (pre_p);
2517
2518 if (ret == GS_ERROR)
2519 ;
2520 else if (TREE_SIDE_EFFECTS (TREE_OPERAND (expr, 1)))
2521 ret = GS_ALL_DONE;
2522 else if (TREE_SIDE_EFFECTS (TREE_OPERAND (expr, 2)))
2523 /* Rewrite "if (a); else b" to "if (!a) b" */
2524 {
2525 TREE_OPERAND (expr, 0) = invert_truthvalue (TREE_OPERAND (expr, 0));
2526 ret = gimplify_expr (&TREE_OPERAND (expr, 0), pre_p, NULL,
2527 is_gimple_condexpr, fb_rvalue);
2528
2529 tmp = TREE_OPERAND (expr, 1);
2530 TREE_OPERAND (expr, 1) = TREE_OPERAND (expr, 2);
2531 TREE_OPERAND (expr, 2) = tmp;
2532 }
2533 else
2534 /* Both arms are empty; replace the COND_EXPR with its predicate. */
2535 expr = TREE_OPERAND (expr, 0);
2536
2537 *expr_p = expr;
2538 return ret;
2539 }
2540
2541 /* A subroutine of gimplify_modify_expr. Replace a MODIFY_EXPR with
2542 a call to __builtin_memcpy. */
2543
2544 static enum gimplify_status
2545 gimplify_modify_expr_to_memcpy (tree *expr_p, tree size, bool want_value)
2546 {
2547 tree args, t, to, to_ptr, from;
2548
2549 to = TREE_OPERAND (*expr_p, 0);
2550 from = TREE_OPERAND (*expr_p, 1);
2551
2552 args = tree_cons (NULL, size, NULL);
2553
2554 t = build_fold_addr_expr (from);
2555 args = tree_cons (NULL, t, args);
2556
2557 to_ptr = build_fold_addr_expr (to);
2558 args = tree_cons (NULL, to_ptr, args);
2559 t = implicit_built_in_decls[BUILT_IN_MEMCPY];
2560 t = build_function_call_expr (t, args);
2561
2562 if (want_value)
2563 {
2564 t = build1 (NOP_EXPR, TREE_TYPE (to_ptr), t);
2565 t = build1 (INDIRECT_REF, TREE_TYPE (to), t);
2566 }
2567
2568 *expr_p = t;
2569 return GS_OK;
2570 }
2571
2572 /* A subroutine of gimplify_modify_expr. Replace a MODIFY_EXPR with
2573 a call to __builtin_memset. In this case we know that the RHS is
2574 a CONSTRUCTOR with an empty element list. */
2575
2576 static enum gimplify_status
2577 gimplify_modify_expr_to_memset (tree *expr_p, tree size, bool want_value)
2578 {
2579 tree args, t, to, to_ptr;
2580
2581 to = TREE_OPERAND (*expr_p, 0);
2582
2583 args = tree_cons (NULL, size, NULL);
2584
2585 args = tree_cons (NULL, integer_zero_node, args);
2586
2587 to_ptr = build_fold_addr_expr (to);
2588 args = tree_cons (NULL, to_ptr, args);
2589 t = implicit_built_in_decls[BUILT_IN_MEMSET];
2590 t = build_function_call_expr (t, args);
2591
2592 if (want_value)
2593 {
2594 t = build1 (NOP_EXPR, TREE_TYPE (to_ptr), t);
2595 t = build1 (INDIRECT_REF, TREE_TYPE (to), t);
2596 }
2597
2598 *expr_p = t;
2599 return GS_OK;
2600 }
2601
2602 /* A subroutine of gimplify_init_ctor_preeval. Called via walk_tree,
2603 determine, cautiously, if a CONSTRUCTOR overlaps the lhs of an
2604 assignment. Returns non-null if we detect a potential overlap. */
2605
2606 struct gimplify_init_ctor_preeval_data
2607 {
2608 /* The base decl of the lhs object. May be NULL, in which case we
2609 have to assume the lhs is indirect. */
2610 tree lhs_base_decl;
2611
2612 /* The alias set of the lhs object. */
2613 int lhs_alias_set;
2614 };
2615
2616 static tree
2617 gimplify_init_ctor_preeval_1 (tree *tp, int *walk_subtrees, void *xdata)
2618 {
2619 struct gimplify_init_ctor_preeval_data *data
2620 = (struct gimplify_init_ctor_preeval_data *) xdata;
2621 tree t = *tp;
2622
2623 /* If we find the base object, obviously we have overlap. */
2624 if (data->lhs_base_decl == t)
2625 return t;
2626
2627 /* If the constructor component is indirect, determine if we have a
2628 potential overlap with the lhs. The only bits of information we
2629 have to go on at this point are addressability and alias sets. */
2630 if (TREE_CODE (t) == INDIRECT_REF
2631 && (!data->lhs_base_decl || TREE_ADDRESSABLE (data->lhs_base_decl))
2632 && alias_sets_conflict_p (data->lhs_alias_set, get_alias_set (t)))
2633 return t;
2634
2635 if (IS_TYPE_OR_DECL_P (t))
2636 *walk_subtrees = 0;
2637 return NULL;
2638 }
2639
2640 /* A subroutine of gimplify_init_constructor. Pre-evaluate *EXPR_P,
2641 force values that overlap with the lhs (as described by *DATA)
2642 into temporaries. */
2643
2644 static void
2645 gimplify_init_ctor_preeval (tree *expr_p, tree *pre_p, tree *post_p,
2646 struct gimplify_init_ctor_preeval_data *data)
2647 {
2648 enum gimplify_status one;
2649
2650 /* If the value is invariant, then there's nothing to pre-evaluate.
2651 But ensure it doesn't have any side-effects since a SAVE_EXPR is
2652 invariant but has side effects and might contain a reference to
2653 the object we're initializing. */
2654 if (TREE_INVARIANT (*expr_p) && !TREE_SIDE_EFFECTS (*expr_p))
2655 return;
2656
2657 /* If the type has non-trivial constructors, we can't pre-evaluate. */
2658 if (TREE_ADDRESSABLE (TREE_TYPE (*expr_p)))
2659 return;
2660
2661 /* Recurse for nested constructors. */
2662 if (TREE_CODE (*expr_p) == CONSTRUCTOR)
2663 {
2664 unsigned HOST_WIDE_INT ix;
2665 constructor_elt *ce;
2666 VEC(constructor_elt,gc) *v = CONSTRUCTOR_ELTS (*expr_p);
2667
2668 for (ix = 0; VEC_iterate (constructor_elt, v, ix, ce); ix++)
2669 gimplify_init_ctor_preeval (&ce->value, pre_p, post_p, data);
2670 return;
2671 }
2672
2673 /* We can't preevaluate if the type contains a placeholder. */
2674 if (type_contains_placeholder_p (TREE_TYPE (*expr_p)))
2675 return;
2676
2677 /* Gimplify the constructor element to something appropriate for the rhs
2678 of a MODIFY_EXPR. Given that we know the lhs is an aggregate, we know
2679 the gimplifier will consider this a store to memory. Doing this
2680 gimplification now means that we won't have to deal with complicated
2681 language-specific trees, nor trees like SAVE_EXPR that can induce
2682 exponential search behavior. */
2683 one = gimplify_expr (expr_p, pre_p, post_p, is_gimple_mem_rhs, fb_rvalue);
2684 if (one == GS_ERROR)
2685 {
2686 *expr_p = NULL;
2687 return;
2688 }
2689
2690 /* If we gimplified to a bare decl, we can be sure that it doesn't overlap
2691 with the lhs, since "a = { .x=a }" doesn't make sense. This will
2692 always be true for all scalars, since is_gimple_mem_rhs insists on a
2693 temporary variable for them. */
2694 if (DECL_P (*expr_p))
2695 return;
2696
2697 /* If this is of variable size, we have no choice but to assume it doesn't
2698 overlap since we can't make a temporary for it. */
2699 if (!TREE_CONSTANT (TYPE_SIZE (TREE_TYPE (*expr_p))))
2700 return;
2701
2702 /* Otherwise, we must search for overlap ... */
2703 if (!walk_tree (expr_p, gimplify_init_ctor_preeval_1, data, NULL))
2704 return;
2705
2706 /* ... and if found, force the value into a temporary. */
2707 *expr_p = get_formal_tmp_var (*expr_p, pre_p);
2708 }
2709
2710 /* A subroutine of gimplify_init_ctor_eval. Create a loop for
2711 a RANGE_EXPR in a CONSTRUCTOR for an array.
2712
2713 var = lower;
2714 loop_entry:
2715 object[var] = value;
2716 if (var == upper)
2717 goto loop_exit;
2718 var = var + 1;
2719 goto loop_entry;
2720 loop_exit:
2721
2722 We increment var _after_ the loop exit check because we might otherwise
2723 fail if upper == TYPE_MAX_VALUE (type for upper).
2724
2725 Note that we never have to deal with SAVE_EXPRs here, because this has
2726 already been taken care of for us, in gimplify_init_ctor_preeval(). */
2727
2728 static void gimplify_init_ctor_eval (tree, VEC(constructor_elt,gc) *,
2729 tree *, bool);
2730
2731 static void
2732 gimplify_init_ctor_eval_range (tree object, tree lower, tree upper,
2733 tree value, tree array_elt_type,
2734 tree *pre_p, bool cleared)
2735 {
2736 tree loop_entry_label, loop_exit_label;
2737 tree var, var_type, cref;
2738
2739 loop_entry_label = create_artificial_label ();
2740 loop_exit_label = create_artificial_label ();
2741
2742 /* Create and initialize the index variable. */
2743 var_type = TREE_TYPE (upper);
2744 var = create_tmp_var (var_type, NULL);
2745 append_to_statement_list (build2 (MODIFY_EXPR, var_type, var, lower), pre_p);
2746
2747 /* Add the loop entry label. */
2748 append_to_statement_list (build1 (LABEL_EXPR,
2749 void_type_node,
2750 loop_entry_label),
2751 pre_p);
2752
2753 /* Build the reference. */
2754 cref = build4 (ARRAY_REF, array_elt_type, unshare_expr (object),
2755 var, NULL_TREE, NULL_TREE);
2756
2757 /* If we are a constructor, just call gimplify_init_ctor_eval to do
2758 the store. Otherwise just assign value to the reference. */
2759
2760 if (TREE_CODE (value) == CONSTRUCTOR)
2761 /* NB we might have to call ourself recursively through
2762 gimplify_init_ctor_eval if the value is a constructor. */
2763 gimplify_init_ctor_eval (cref, CONSTRUCTOR_ELTS (value),
2764 pre_p, cleared);
2765 else
2766 append_to_statement_list (build2 (MODIFY_EXPR, TREE_TYPE (cref),
2767 cref, value),
2768 pre_p);
2769
2770 /* We exit the loop when the index var is equal to the upper bound. */
2771 gimplify_and_add (build3 (COND_EXPR, void_type_node,
2772 build2 (EQ_EXPR, boolean_type_node,
2773 var, upper),
2774 build1 (GOTO_EXPR,
2775 void_type_node,
2776 loop_exit_label),
2777 NULL_TREE),
2778 pre_p);
2779
2780 /* Otherwise, increment the index var... */
2781 append_to_statement_list (build2 (MODIFY_EXPR, var_type, var,
2782 build2 (PLUS_EXPR, var_type, var,
2783 fold_convert (var_type,
2784 integer_one_node))),
2785 pre_p);
2786
2787 /* ...and jump back to the loop entry. */
2788 append_to_statement_list (build1 (GOTO_EXPR,
2789 void_type_node,
2790 loop_entry_label),
2791 pre_p);
2792
2793 /* Add the loop exit label. */
2794 append_to_statement_list (build1 (LABEL_EXPR,
2795 void_type_node,
2796 loop_exit_label),
2797 pre_p);
2798 }
2799
2800 /* Return true if FDECL is accessing a field that is zero sized. */
2801
2802 static bool
2803 zero_sized_field_decl (tree fdecl)
2804 {
2805 if (TREE_CODE (fdecl) == FIELD_DECL && DECL_SIZE (fdecl)
2806 && integer_zerop (DECL_SIZE (fdecl)))
2807 return true;
2808 return false;
2809 }
2810
2811 /* Return true if TYPE is zero sized. */
2812
2813 static bool
2814 zero_sized_type (tree type)
2815 {
2816 if (AGGREGATE_TYPE_P (type) && TYPE_SIZE (type)
2817 && integer_zerop (TYPE_SIZE (type)))
2818 return true;
2819 return false;
2820 }
2821
2822 /* A subroutine of gimplify_init_constructor. Generate individual
2823 MODIFY_EXPRs for a CONSTRUCTOR. OBJECT is the LHS against which the
2824 assignments should happen. ELTS is the CONSTRUCTOR_ELTS of the
2825 CONSTRUCTOR. CLEARED is true if the entire LHS object has been
2826 zeroed first. */
2827
2828 static void
2829 gimplify_init_ctor_eval (tree object, VEC(constructor_elt,gc) *elts,
2830 tree *pre_p, bool cleared)
2831 {
2832 tree array_elt_type = NULL;
2833 unsigned HOST_WIDE_INT ix;
2834 tree purpose, value;
2835
2836 if (TREE_CODE (TREE_TYPE (object)) == ARRAY_TYPE)
2837 array_elt_type = TYPE_MAIN_VARIANT (TREE_TYPE (TREE_TYPE (object)));
2838
2839 FOR_EACH_CONSTRUCTOR_ELT (elts, ix, purpose, value)
2840 {
2841 tree cref, init;
2842
2843 /* NULL values are created above for gimplification errors. */
2844 if (value == NULL)
2845 continue;
2846
2847 if (cleared && initializer_zerop (value))
2848 continue;
2849
2850 /* ??? Here's to hoping the front end fills in all of the indices,
2851 so we don't have to figure out what's missing ourselves. */
2852 gcc_assert (purpose);
2853
2854 /* Skip zero-sized fields, unless value has side-effects. This can
2855 happen with calls to functions returning a zero-sized type, which
2856 we shouldn't discard. As a number of downstream passes don't
2857 expect sets of zero-sized fields, we rely on the gimplification of
2858 the MODIFY_EXPR we make below to drop the assignment statement. */
2859 if (! TREE_SIDE_EFFECTS (value) && zero_sized_field_decl (purpose))
2860 continue;
2861
2862 /* If we have a RANGE_EXPR, we have to build a loop to assign the
2863 whole range. */
2864 if (TREE_CODE (purpose) == RANGE_EXPR)
2865 {
2866 tree lower = TREE_OPERAND (purpose, 0);
2867 tree upper = TREE_OPERAND (purpose, 1);
2868
2869 /* If the lower bound is equal to upper, just treat it as if
2870 upper was the index. */
2871 if (simple_cst_equal (lower, upper))
2872 purpose = upper;
2873 else
2874 {
2875 gimplify_init_ctor_eval_range (object, lower, upper, value,
2876 array_elt_type, pre_p, cleared);
2877 continue;
2878 }
2879 }
2880
2881 if (array_elt_type)
2882 {
2883 cref = build4 (ARRAY_REF, array_elt_type, unshare_expr (object),
2884 purpose, NULL_TREE, NULL_TREE);
2885 }
2886 else
2887 {
2888 gcc_assert (TREE_CODE (purpose) == FIELD_DECL);
2889 cref = build3 (COMPONENT_REF, TREE_TYPE (purpose),
2890 unshare_expr (object), purpose, NULL_TREE);
2891 }
2892
2893 if (TREE_CODE (value) == CONSTRUCTOR
2894 && TREE_CODE (TREE_TYPE (value)) != VECTOR_TYPE)
2895 gimplify_init_ctor_eval (cref, CONSTRUCTOR_ELTS (value),
2896 pre_p, cleared);
2897 else
2898 {
2899 init = build2 (INIT_EXPR, TREE_TYPE (cref), cref, value);
2900 gimplify_and_add (init, pre_p);
2901 }
2902 }
2903 }
2904
2905 /* A subroutine of gimplify_modify_expr. Break out elements of a
2906 CONSTRUCTOR used as an initializer into separate MODIFY_EXPRs.
2907
2908 Note that we still need to clear any elements that don't have explicit
2909 initializers, so if not all elements are initialized we keep the
2910 original MODIFY_EXPR, we just remove all of the constructor elements. */
2911
2912 static enum gimplify_status
2913 gimplify_init_constructor (tree *expr_p, tree *pre_p,
2914 tree *post_p, bool want_value)
2915 {
2916 tree object;
2917 tree ctor = TREE_OPERAND (*expr_p, 1);
2918 tree type = TREE_TYPE (ctor);
2919 enum gimplify_status ret;
2920 VEC(constructor_elt,gc) *elts;
2921
2922 if (TREE_CODE (ctor) != CONSTRUCTOR)
2923 return GS_UNHANDLED;
2924
2925 ret = gimplify_expr (&TREE_OPERAND (*expr_p, 0), pre_p, post_p,
2926 is_gimple_lvalue, fb_lvalue);
2927 if (ret == GS_ERROR)
2928 return ret;
2929 object = TREE_OPERAND (*expr_p, 0);
2930
2931 elts = CONSTRUCTOR_ELTS (ctor);
2932
2933 ret = GS_ALL_DONE;
2934 switch (TREE_CODE (type))
2935 {
2936 case RECORD_TYPE:
2937 case UNION_TYPE:
2938 case QUAL_UNION_TYPE:
2939 case ARRAY_TYPE:
2940 {
2941 struct gimplify_init_ctor_preeval_data preeval_data;
2942 HOST_WIDE_INT num_type_elements, num_ctor_elements;
2943 HOST_WIDE_INT num_nonzero_elements, num_nonconstant_elements;
2944 bool cleared;
2945
2946 /* Aggregate types must lower constructors to initialization of
2947 individual elements. The exception is that a CONSTRUCTOR node
2948 with no elements indicates zero-initialization of the whole. */
2949 if (VEC_empty (constructor_elt, elts))
2950 break;
2951
2952 categorize_ctor_elements (ctor, &num_nonzero_elements,
2953 &num_nonconstant_elements,
2954 &num_ctor_elements, &cleared);
2955
2956 /* If a const aggregate variable is being initialized, then it
2957 should never be a lose to promote the variable to be static. */
2958 if (num_nonconstant_elements == 0
2959 && num_nonzero_elements > 1
2960 && TREE_READONLY (object)
2961 && TREE_CODE (object) == VAR_DECL)
2962 {
2963 DECL_INITIAL (object) = ctor;
2964 TREE_STATIC (object) = 1;
2965 if (!DECL_NAME (object))
2966 DECL_NAME (object) = create_tmp_var_name ("C");
2967 walk_tree (&DECL_INITIAL (object), force_labels_r, NULL, NULL);
2968
2969 /* ??? C++ doesn't automatically append a .<number> to the
2970 assembler name, and even when it does, it looks a FE private
2971 data structures to figure out what that number should be,
2972 which are not set for this variable. I suppose this is
2973 important for local statics for inline functions, which aren't
2974 "local" in the object file sense. So in order to get a unique
2975 TU-local symbol, we must invoke the lhd version now. */
2976 lhd_set_decl_assembler_name (object);
2977
2978 *expr_p = NULL_TREE;
2979 break;
2980 }
2981
2982 /* If there are "lots" of initialized elements, even discounting
2983 those that are not address constants (and thus *must* be
2984 computed at runtime), then partition the constructor into
2985 constant and non-constant parts. Block copy the constant
2986 parts in, then generate code for the non-constant parts. */
2987 /* TODO. There's code in cp/typeck.c to do this. */
2988
2989 num_type_elements = count_type_elements (type, true);
2990
2991 /* If count_type_elements could not determine number of type elements
2992 for a constant-sized object, assume clearing is needed.
2993 Don't do this for variable-sized objects, as store_constructor
2994 will ignore the clearing of variable-sized objects. */
2995 if (num_type_elements < 0 && int_size_in_bytes (type) >= 0)
2996 cleared = true;
2997 /* If there are "lots" of zeros, then block clear the object first. */
2998 else if (num_type_elements - num_nonzero_elements > CLEAR_RATIO
2999 && num_nonzero_elements < num_type_elements/4)
3000 cleared = true;
3001 /* ??? This bit ought not be needed. For any element not present
3002 in the initializer, we should simply set them to zero. Except
3003 we'd need to *find* the elements that are not present, and that
3004 requires trickery to avoid quadratic compile-time behavior in
3005 large cases or excessive memory use in small cases. */
3006 else if (num_ctor_elements < num_type_elements)
3007 cleared = true;
3008
3009 /* If there are "lots" of initialized elements, and all of them
3010 are valid address constants, then the entire initializer can
3011 be dropped to memory, and then memcpy'd out. Don't do this
3012 for sparse arrays, though, as it's more efficient to follow
3013 the standard CONSTRUCTOR behavior of memset followed by
3014 individual element initialization. */
3015 if (num_nonconstant_elements == 0 && !cleared)
3016 {
3017 HOST_WIDE_INT size = int_size_in_bytes (type);
3018 unsigned int align;
3019
3020 /* ??? We can still get unbounded array types, at least
3021 from the C++ front end. This seems wrong, but attempt
3022 to work around it for now. */
3023 if (size < 0)
3024 {
3025 size = int_size_in_bytes (TREE_TYPE (object));
3026 if (size >= 0)
3027 TREE_TYPE (ctor) = type = TREE_TYPE (object);
3028 }
3029
3030 /* Find the maximum alignment we can assume for the object. */
3031 /* ??? Make use of DECL_OFFSET_ALIGN. */
3032 if (DECL_P (object))
3033 align = DECL_ALIGN (object);
3034 else
3035 align = TYPE_ALIGN (type);
3036
3037 if (size > 0 && !can_move_by_pieces (size, align))
3038 {
3039 tree new = create_tmp_var_raw (type, "C");
3040
3041 gimple_add_tmp_var (new);
3042 TREE_STATIC (new) = 1;
3043 TREE_READONLY (new) = 1;
3044 DECL_INITIAL (new) = ctor;
3045 if (align > DECL_ALIGN (new))
3046 {
3047 DECL_ALIGN (new) = align;
3048 DECL_USER_ALIGN (new) = 1;
3049 }
3050 walk_tree (&DECL_INITIAL (new), force_labels_r, NULL, NULL);
3051
3052 TREE_OPERAND (*expr_p, 1) = new;
3053
3054 /* This is no longer an assignment of a CONSTRUCTOR, but
3055 we still may have processing to do on the LHS. So
3056 pretend we didn't do anything here to let that happen. */
3057 return GS_UNHANDLED;
3058 }
3059 }
3060
3061 if (cleared)
3062 {
3063 /* Zap the CONSTRUCTOR element list, which simplifies this case.
3064 Note that we still have to gimplify, in order to handle the
3065 case of variable sized types. Avoid shared tree structures. */
3066 CONSTRUCTOR_ELTS (ctor) = NULL;
3067 object = unshare_expr (object);
3068 gimplify_stmt (expr_p);
3069 append_to_statement_list (*expr_p, pre_p);
3070 }
3071
3072 /* If we have not block cleared the object, or if there are nonzero
3073 elements in the constructor, add assignments to the individual
3074 scalar fields of the object. */
3075 if (!cleared || num_nonzero_elements > 0)
3076 {
3077 preeval_data.lhs_base_decl = get_base_address (object);
3078 if (!DECL_P (preeval_data.lhs_base_decl))
3079 preeval_data.lhs_base_decl = NULL;
3080 preeval_data.lhs_alias_set = get_alias_set (object);
3081
3082 gimplify_init_ctor_preeval (&TREE_OPERAND (*expr_p, 1),
3083 pre_p, post_p, &preeval_data);
3084 gimplify_init_ctor_eval (object, elts, pre_p, cleared);
3085 }
3086
3087 *expr_p = NULL_TREE;
3088 }
3089 break;
3090
3091 case COMPLEX_TYPE:
3092 {
3093 tree r, i;
3094
3095 /* Extract the real and imaginary parts out of the ctor. */
3096 gcc_assert (VEC_length (constructor_elt, elts) == 2);
3097 r = VEC_index (constructor_elt, elts, 0)->value;
3098 i = VEC_index (constructor_elt, elts, 1)->value;
3099 if (r == NULL || i == NULL)
3100 {
3101 tree zero = fold_convert (TREE_TYPE (type), integer_zero_node);
3102 if (r == NULL)
3103 r = zero;
3104 if (i == NULL)
3105 i = zero;
3106 }
3107
3108 /* Complex types have either COMPLEX_CST or COMPLEX_EXPR to
3109 represent creation of a complex value. */
3110 if (TREE_CONSTANT (r) && TREE_CONSTANT (i))
3111 {
3112 ctor = build_complex (type, r, i);
3113 TREE_OPERAND (*expr_p, 1) = ctor;
3114 }
3115 else
3116 {
3117 ctor = build2 (COMPLEX_EXPR, type, r, i);
3118 TREE_OPERAND (*expr_p, 1) = ctor;
3119 ret = gimplify_expr (&TREE_OPERAND (*expr_p, 1), pre_p, post_p,
3120 rhs_predicate_for (TREE_OPERAND (*expr_p, 0)),
3121 fb_rvalue);
3122 }
3123 }
3124 break;
3125
3126 case VECTOR_TYPE:
3127 {
3128 unsigned HOST_WIDE_INT ix;
3129 constructor_elt *ce;
3130
3131 /* Go ahead and simplify constant constructors to VECTOR_CST. */
3132 if (TREE_CONSTANT (ctor))
3133 {
3134 bool constant_p = true;
3135 tree value;
3136
3137 /* Even when ctor is constant, it might contain non-*_CST
3138 elements (e.g. { 1.0/0.0 - 1.0/0.0, 0.0 }) and those don't
3139 belong into VECTOR_CST nodes. */
3140 FOR_EACH_CONSTRUCTOR_VALUE (elts, ix, value)
3141 if (!CONSTANT_CLASS_P (value))
3142 {
3143 constant_p = false;
3144 break;
3145 }
3146
3147 if (constant_p)
3148 {
3149 TREE_OPERAND (*expr_p, 1) = build_vector_from_ctor (type, elts);
3150 break;
3151 }
3152 }
3153
3154 /* Vector types use CONSTRUCTOR all the way through gimple
3155 compilation as a general initializer. */
3156 for (ix = 0; VEC_iterate (constructor_elt, elts, ix, ce); ix++)
3157 {
3158 enum gimplify_status tret;
3159 tret = gimplify_expr (&ce->value, pre_p, post_p,
3160 is_gimple_val, fb_rvalue);
3161 if (tret == GS_ERROR)
3162 ret = GS_ERROR;
3163 }
3164 }
3165 break;
3166
3167 default:
3168 /* So how did we get a CONSTRUCTOR for a scalar type? */
3169 gcc_unreachable ();
3170 }
3171
3172 if (ret == GS_ERROR)
3173 return GS_ERROR;
3174 else if (want_value)
3175 {
3176 append_to_statement_list (*expr_p, pre_p);
3177 *expr_p = object;
3178 return GS_OK;
3179 }
3180 else
3181 return GS_ALL_DONE;
3182 }
3183
3184 /* Given a pointer value OP0, return a simplified version of an
3185 indirection through OP0, or NULL_TREE if no simplification is
3186 possible. This may only be applied to a rhs of an expression.
3187 Note that the resulting type may be different from the type pointed
3188 to in the sense that it is still compatible from the langhooks
3189 point of view. */
3190
3191 static tree
3192 fold_indirect_ref_rhs (tree t)
3193 {
3194 tree type = TREE_TYPE (TREE_TYPE (t));
3195 tree sub = t;
3196 tree subtype;
3197
3198 STRIP_NOPS (sub);
3199 subtype = TREE_TYPE (sub);
3200 if (!POINTER_TYPE_P (subtype))
3201 return NULL_TREE;
3202
3203 if (TREE_CODE (sub) == ADDR_EXPR)
3204 {
3205 tree op = TREE_OPERAND (sub, 0);
3206 tree optype = TREE_TYPE (op);
3207 /* *&p => p */
3208 if (lang_hooks.types_compatible_p (type, optype))
3209 return op;
3210 /* *(foo *)&fooarray => fooarray[0] */
3211 else if (TREE_CODE (optype) == ARRAY_TYPE
3212 && lang_hooks.types_compatible_p (type, TREE_TYPE (optype)))
3213 {
3214 tree type_domain = TYPE_DOMAIN (optype);
3215 tree min_val = size_zero_node;
3216 if (type_domain && TYPE_MIN_VALUE (type_domain))
3217 min_val = TYPE_MIN_VALUE (type_domain);
3218 return build4 (ARRAY_REF, type, op, min_val, NULL_TREE, NULL_TREE);
3219 }
3220 }
3221
3222 /* *(foo *)fooarrptr => (*fooarrptr)[0] */
3223 if (TREE_CODE (TREE_TYPE (subtype)) == ARRAY_TYPE
3224 && lang_hooks.types_compatible_p (type, TREE_TYPE (TREE_TYPE (subtype))))
3225 {
3226 tree type_domain;
3227 tree min_val = size_zero_node;
3228 tree osub = sub;
3229 sub = fold_indirect_ref_rhs (sub);
3230 if (! sub)
3231 sub = build1 (INDIRECT_REF, TREE_TYPE (subtype), osub);
3232 type_domain = TYPE_DOMAIN (TREE_TYPE (sub));
3233 if (type_domain && TYPE_MIN_VALUE (type_domain))
3234 min_val = TYPE_MIN_VALUE (type_domain);
3235 return build4 (ARRAY_REF, type, sub, min_val, NULL_TREE, NULL_TREE);
3236 }
3237
3238 return NULL_TREE;
3239 }
3240
3241 /* Subroutine of gimplify_modify_expr to do simplifications of MODIFY_EXPRs
3242 based on the code of the RHS. We loop for as long as something changes. */
3243
3244 static enum gimplify_status
3245 gimplify_modify_expr_rhs (tree *expr_p, tree *from_p, tree *to_p, tree *pre_p,
3246 tree *post_p, bool want_value)
3247 {
3248 enum gimplify_status ret = GS_OK;
3249
3250 while (ret != GS_UNHANDLED)
3251 switch (TREE_CODE (*from_p))
3252 {
3253 case INDIRECT_REF:
3254 {
3255 /* If we have code like
3256
3257 *(const A*)(A*)&x
3258
3259 where the type of "x" is a (possibly cv-qualified variant
3260 of "A"), treat the entire expression as identical to "x".
3261 This kind of code arises in C++ when an object is bound
3262 to a const reference, and if "x" is a TARGET_EXPR we want
3263 to take advantage of the optimization below. */
3264 tree t = fold_indirect_ref_rhs (TREE_OPERAND (*from_p, 0));
3265 if (t)
3266 {
3267 *from_p = t;
3268 ret = GS_OK;
3269 }
3270 else
3271 ret = GS_UNHANDLED;
3272 break;
3273 }
3274
3275 case TARGET_EXPR:
3276 {
3277 /* If we are initializing something from a TARGET_EXPR, strip the
3278 TARGET_EXPR and initialize it directly, if possible. This can't
3279 be done if the initializer is void, since that implies that the
3280 temporary is set in some non-trivial way.
3281
3282 ??? What about code that pulls out the temp and uses it
3283 elsewhere? I think that such code never uses the TARGET_EXPR as
3284 an initializer. If I'm wrong, we'll die because the temp won't
3285 have any RTL. In that case, I guess we'll need to replace
3286 references somehow. */
3287 tree init = TARGET_EXPR_INITIAL (*from_p);
3288
3289 if (!VOID_TYPE_P (TREE_TYPE (init)))
3290 {
3291 *from_p = init;
3292 ret = GS_OK;
3293 }
3294 else
3295 ret = GS_UNHANDLED;
3296 }
3297 break;
3298
3299 case COMPOUND_EXPR:
3300 /* Remove any COMPOUND_EXPR in the RHS so the following cases will be
3301 caught. */
3302 gimplify_compound_expr (from_p, pre_p, true);
3303 ret = GS_OK;
3304 break;
3305
3306 case CONSTRUCTOR:
3307 /* If we're initializing from a CONSTRUCTOR, break this into
3308 individual MODIFY_EXPRs. */
3309 return gimplify_init_constructor (expr_p, pre_p, post_p, want_value);
3310
3311 case COND_EXPR:
3312 /* If we're assigning to a non-register type, push the assignment
3313 down into the branches. This is mandatory for ADDRESSABLE types,
3314 since we cannot generate temporaries for such, but it saves a
3315 copy in other cases as well. */
3316 if (!is_gimple_reg_type (TREE_TYPE (*from_p)))
3317 {
3318 /* This code should mirror the code in gimplify_cond_expr. */
3319 enum tree_code code = TREE_CODE (*expr_p);
3320 tree cond = *from_p;
3321 tree result = *to_p;
3322
3323 ret = gimplify_expr (&result, pre_p, post_p,
3324 is_gimple_min_lval, fb_lvalue);
3325 if (ret != GS_ERROR)
3326 ret = GS_OK;
3327
3328 if (TREE_TYPE (TREE_OPERAND (cond, 1)) != void_type_node)
3329 TREE_OPERAND (cond, 1)
3330 = build2 (code, void_type_node, result,
3331 TREE_OPERAND (cond, 1));
3332 if (TREE_TYPE (TREE_OPERAND (cond, 2)) != void_type_node)
3333 TREE_OPERAND (cond, 2)
3334 = build2 (code, void_type_node, unshare_expr (result),
3335 TREE_OPERAND (cond, 2));
3336
3337 TREE_TYPE (cond) = void_type_node;
3338 recalculate_side_effects (cond);
3339
3340 if (want_value)
3341 {
3342 gimplify_and_add (cond, pre_p);
3343 *expr_p = unshare_expr (result);
3344 }
3345 else
3346 *expr_p = cond;
3347 return ret;
3348 }
3349 else
3350 ret = GS_UNHANDLED;
3351 break;
3352
3353 case CALL_EXPR:
3354 /* For calls that return in memory, give *to_p as the CALL_EXPR's
3355 return slot so that we don't generate a temporary. */
3356 if (!CALL_EXPR_RETURN_SLOT_OPT (*from_p)
3357 && aggregate_value_p (*from_p, *from_p))
3358 {
3359 bool use_target;
3360
3361 if (!(rhs_predicate_for (*to_p))(*from_p))
3362 /* If we need a temporary, *to_p isn't accurate. */
3363 use_target = false;
3364 else if (TREE_CODE (*to_p) == RESULT_DECL
3365 && DECL_NAME (*to_p) == NULL_TREE
3366 && needs_to_live_in_memory (*to_p))
3367 /* It's OK to use the return slot directly unless it's an NRV. */
3368 use_target = true;
3369 else if (is_gimple_reg_type (TREE_TYPE (*to_p))
3370 || (DECL_P (*to_p) && DECL_REGISTER (*to_p)))
3371 /* Don't force regs into memory. */
3372 use_target = false;
3373 else if (TREE_CODE (*to_p) == VAR_DECL
3374 && DECL_GIMPLE_FORMAL_TEMP_P (*to_p))
3375 /* Don't use the original target if it's a formal temp; we
3376 don't want to take their addresses. */
3377 use_target = false;
3378 else if (TREE_CODE (*expr_p) == INIT_EXPR)
3379 /* It's OK to use the target directly if it's being
3380 initialized. */
3381 use_target = true;
3382 else if (!is_gimple_non_addressable (*to_p))
3383 /* Don't use the original target if it's already addressable;
3384 if its address escapes, and the called function uses the
3385 NRV optimization, a conforming program could see *to_p
3386 change before the called function returns; see c++/19317.
3387 When optimizing, the return_slot pass marks more functions
3388 as safe after we have escape info. */
3389 use_target = false;
3390 else
3391 use_target = true;
3392
3393 if (use_target)
3394 {
3395 CALL_EXPR_RETURN_SLOT_OPT (*from_p) = 1;
3396 lang_hooks.mark_addressable (*to_p);
3397 }
3398 }
3399
3400 ret = GS_UNHANDLED;
3401 break;
3402
3403 default:
3404 ret = GS_UNHANDLED;
3405 break;
3406 }
3407
3408 return ret;
3409 }
3410
3411 /* Promote partial stores to COMPLEX variables to total stores. *EXPR_P is
3412 a MODIFY_EXPR with a lhs of a REAL/IMAGPART_EXPR of a variable with
3413 DECL_COMPLEX_GIMPLE_REG_P set. */
3414
3415 static enum gimplify_status
3416 gimplify_modify_expr_complex_part (tree *expr_p, tree *pre_p, bool want_value)
3417 {
3418 enum tree_code code, ocode;
3419 tree lhs, rhs, new_rhs, other, realpart, imagpart;
3420
3421 lhs = TREE_OPERAND (*expr_p, 0);
3422 rhs = TREE_OPERAND (*expr_p, 1);
3423 code = TREE_CODE (lhs);
3424 lhs = TREE_OPERAND (lhs, 0);
3425
3426 ocode = code == REALPART_EXPR ? IMAGPART_EXPR : REALPART_EXPR;
3427 other = build1 (ocode, TREE_TYPE (rhs), lhs);
3428 other = get_formal_tmp_var (other, pre_p);
3429
3430 realpart = code == REALPART_EXPR ? rhs : other;
3431 imagpart = code == REALPART_EXPR ? other : rhs;
3432
3433 if (TREE_CONSTANT (realpart) && TREE_CONSTANT (imagpart))
3434 new_rhs = build_complex (TREE_TYPE (lhs), realpart, imagpart);
3435 else
3436 new_rhs = build2 (COMPLEX_EXPR, TREE_TYPE (lhs), realpart, imagpart);
3437
3438 TREE_OPERAND (*expr_p, 0) = lhs;
3439 TREE_OPERAND (*expr_p, 1) = new_rhs;
3440
3441 if (want_value)
3442 {
3443 append_to_statement_list (*expr_p, pre_p);
3444 *expr_p = rhs;
3445 }
3446
3447 return GS_ALL_DONE;
3448 }
3449
3450 /* Gimplify the MODIFY_EXPR node pointed to by EXPR_P.
3451
3452 modify_expr
3453 : varname '=' rhs
3454 | '*' ID '=' rhs
3455
3456 PRE_P points to the list where side effects that must happen before
3457 *EXPR_P should be stored.
3458
3459 POST_P points to the list where side effects that must happen after
3460 *EXPR_P should be stored.
3461
3462 WANT_VALUE is nonzero iff we want to use the value of this expression
3463 in another expression. */
3464
3465 static enum gimplify_status
3466 gimplify_modify_expr (tree *expr_p, tree *pre_p, tree *post_p, bool want_value)
3467 {
3468 tree *from_p = &TREE_OPERAND (*expr_p, 1);
3469 tree *to_p = &TREE_OPERAND (*expr_p, 0);
3470 enum gimplify_status ret = GS_UNHANDLED;
3471
3472 gcc_assert (TREE_CODE (*expr_p) == MODIFY_EXPR
3473 || TREE_CODE (*expr_p) == INIT_EXPR);
3474
3475 /* For zero sized types only gimplify the left hand side and right hand side
3476 as statements and throw away the assignment. */
3477 if (zero_sized_type (TREE_TYPE (*from_p)))
3478 {
3479 gimplify_stmt (from_p);
3480 gimplify_stmt (to_p);
3481 append_to_statement_list (*from_p, pre_p);
3482 append_to_statement_list (*to_p, pre_p);
3483 *expr_p = NULL_TREE;
3484 return GS_ALL_DONE;
3485 }
3486
3487 /* See if any simplifications can be done based on what the RHS is. */
3488 ret = gimplify_modify_expr_rhs (expr_p, from_p, to_p, pre_p, post_p,
3489 want_value);
3490 if (ret != GS_UNHANDLED)
3491 return ret;
3492
3493 /* If the value being copied is of variable width, compute the length
3494 of the copy into a WITH_SIZE_EXPR. Note that we need to do this
3495 before gimplifying any of the operands so that we can resolve any
3496 PLACEHOLDER_EXPRs in the size. Also note that the RTL expander uses
3497 the size of the expression to be copied, not of the destination, so
3498 that is what we must here. */
3499 maybe_with_size_expr (from_p);
3500
3501 ret = gimplify_expr (to_p, pre_p, post_p, is_gimple_lvalue, fb_lvalue);
3502 if (ret == GS_ERROR)
3503 return ret;
3504
3505 ret = gimplify_expr (from_p, pre_p, post_p,
3506 rhs_predicate_for (*to_p), fb_rvalue);
3507 if (ret == GS_ERROR)
3508 return ret;
3509
3510 /* Now see if the above changed *from_p to something we handle specially. */
3511 ret = gimplify_modify_expr_rhs (expr_p, from_p, to_p, pre_p, post_p,
3512 want_value);
3513 if (ret != GS_UNHANDLED)
3514 return ret;
3515
3516 /* If we've got a variable sized assignment between two lvalues (i.e. does
3517 not involve a call), then we can make things a bit more straightforward
3518 by converting the assignment to memcpy or memset. */
3519 if (TREE_CODE (*from_p) == WITH_SIZE_EXPR)
3520 {
3521 tree from = TREE_OPERAND (*from_p, 0);
3522 tree size = TREE_OPERAND (*from_p, 1);
3523
3524 if (TREE_CODE (from) == CONSTRUCTOR)
3525 return gimplify_modify_expr_to_memset (expr_p, size, want_value);
3526 if (is_gimple_addressable (from))
3527 {
3528 *from_p = from;
3529 return gimplify_modify_expr_to_memcpy (expr_p, size, want_value);
3530 }
3531 }
3532
3533 /* Transform partial stores to non-addressable complex variables into
3534 total stores. This allows us to use real instead of virtual operands
3535 for these variables, which improves optimization. */
3536 if ((TREE_CODE (*to_p) == REALPART_EXPR
3537 || TREE_CODE (*to_p) == IMAGPART_EXPR)
3538 && is_gimple_reg (TREE_OPERAND (*to_p, 0)))
3539 return gimplify_modify_expr_complex_part (expr_p, pre_p, want_value);
3540
3541 if (gimplify_ctxp->into_ssa && is_gimple_reg (*to_p))
3542 {
3543 /* If we've somehow already got an SSA_NAME on the LHS, then
3544 we're probably modified it twice. Not good. */
3545 gcc_assert (TREE_CODE (*to_p) != SSA_NAME);
3546 *to_p = make_ssa_name (*to_p, *expr_p);
3547 }
3548
3549 if (want_value)
3550 {
3551 append_to_statement_list (*expr_p, pre_p);
3552 *expr_p = *to_p;
3553 return GS_OK;
3554 }
3555
3556 return GS_ALL_DONE;
3557 }
3558
3559 /* Gimplify a comparison between two variable-sized objects. Do this
3560 with a call to BUILT_IN_MEMCMP. */
3561
3562 static enum gimplify_status
3563 gimplify_variable_sized_compare (tree *expr_p)
3564 {
3565 tree op0 = TREE_OPERAND (*expr_p, 0);
3566 tree op1 = TREE_OPERAND (*expr_p, 1);
3567 tree args, t, dest;
3568
3569 t = TYPE_SIZE_UNIT (TREE_TYPE (op0));
3570 t = unshare_expr (t);
3571 t = SUBSTITUTE_PLACEHOLDER_IN_EXPR (t, op0);
3572 args = tree_cons (NULL, t, NULL);
3573 t = build_fold_addr_expr (op1);
3574 args = tree_cons (NULL, t, args);
3575 dest = build_fold_addr_expr (op0);
3576 args = tree_cons (NULL, dest, args);
3577 t = implicit_built_in_decls[BUILT_IN_MEMCMP];
3578 t = build_function_call_expr (t, args);
3579 *expr_p
3580 = build2 (TREE_CODE (*expr_p), TREE_TYPE (*expr_p), t, integer_zero_node);
3581
3582 return GS_OK;
3583 }
3584
3585 /* Gimplify TRUTH_ANDIF_EXPR and TRUTH_ORIF_EXPR expressions. EXPR_P
3586 points to the expression to gimplify.
3587
3588 Expressions of the form 'a && b' are gimplified to:
3589
3590 a && b ? true : false
3591
3592 gimplify_cond_expr will do the rest.
3593
3594 PRE_P points to the list where side effects that must happen before
3595 *EXPR_P should be stored. */
3596
3597 static enum gimplify_status
3598 gimplify_boolean_expr (tree *expr_p)
3599 {
3600 /* Preserve the original type of the expression. */
3601 tree type = TREE_TYPE (*expr_p);
3602
3603 *expr_p = build3 (COND_EXPR, type, *expr_p,
3604 fold_convert (type, boolean_true_node),
3605 fold_convert (type, boolean_false_node));
3606
3607 return GS_OK;
3608 }
3609
3610 /* Gimplifies an expression sequence. This function gimplifies each
3611 expression and re-writes the original expression with the last
3612 expression of the sequence in GIMPLE form.
3613
3614 PRE_P points to the list where the side effects for all the
3615 expressions in the sequence will be emitted.
3616
3617 WANT_VALUE is true when the result of the last COMPOUND_EXPR is used. */
3618 /* ??? Should rearrange to share the pre-queue with all the indirect
3619 invocations of gimplify_expr. Would probably save on creations
3620 of statement_list nodes. */
3621
3622 static enum gimplify_status
3623 gimplify_compound_expr (tree *expr_p, tree *pre_p, bool want_value)
3624 {
3625 tree t = *expr_p;
3626
3627 do
3628 {
3629 tree *sub_p = &TREE_OPERAND (t, 0);
3630
3631 if (TREE_CODE (*sub_p) == COMPOUND_EXPR)
3632 gimplify_compound_expr (sub_p, pre_p, false);
3633 else
3634 gimplify_stmt (sub_p);
3635 append_to_statement_list (*sub_p, pre_p);
3636
3637 t = TREE_OPERAND (t, 1);
3638 }
3639 while (TREE_CODE (t) == COMPOUND_EXPR);
3640
3641 *expr_p = t;
3642 if (want_value)
3643 return GS_OK;
3644 else
3645 {
3646 gimplify_stmt (expr_p);
3647 return GS_ALL_DONE;
3648 }
3649 }
3650
3651 /* Gimplifies a statement list. These may be created either by an
3652 enlightened front-end, or by shortcut_cond_expr. */
3653
3654 static enum gimplify_status
3655 gimplify_statement_list (tree *expr_p)
3656 {
3657 tree_stmt_iterator i = tsi_start (*expr_p);
3658
3659 while (!tsi_end_p (i))
3660 {
3661 tree t;
3662
3663 gimplify_stmt (tsi_stmt_ptr (i));
3664
3665 t = tsi_stmt (i);
3666 if (t == NULL)
3667 tsi_delink (&i);
3668 else if (TREE_CODE (t) == STATEMENT_LIST)
3669 {
3670 tsi_link_before (&i, t, TSI_SAME_STMT);
3671 tsi_delink (&i);
3672 }
3673 else
3674 tsi_next (&i);
3675 }
3676
3677 return GS_ALL_DONE;
3678 }
3679
3680 /* Gimplify a SAVE_EXPR node. EXPR_P points to the expression to
3681 gimplify. After gimplification, EXPR_P will point to a new temporary
3682 that holds the original value of the SAVE_EXPR node.
3683
3684 PRE_P points to the list where side effects that must happen before
3685 *EXPR_P should be stored. */
3686
3687 static enum gimplify_status
3688 gimplify_save_expr (tree *expr_p, tree *pre_p, tree *post_p)
3689 {
3690 enum gimplify_status ret = GS_ALL_DONE;
3691 tree val;
3692
3693 gcc_assert (TREE_CODE (*expr_p) == SAVE_EXPR);
3694 val = TREE_OPERAND (*expr_p, 0);
3695
3696 /* If the SAVE_EXPR has not been resolved, then evaluate it once. */
3697 if (!SAVE_EXPR_RESOLVED_P (*expr_p))
3698 {
3699 /* The operand may be a void-valued expression such as SAVE_EXPRs
3700 generated by the Java frontend for class initialization. It is
3701 being executed only for its side-effects. */
3702 if (TREE_TYPE (val) == void_type_node)
3703 {
3704 ret = gimplify_expr (&TREE_OPERAND (*expr_p, 0), pre_p, post_p,
3705 is_gimple_stmt, fb_none);
3706 append_to_statement_list (TREE_OPERAND (*expr_p, 0), pre_p);
3707 val = NULL;
3708 }
3709 else
3710 val = get_initialized_tmp_var (val, pre_p, post_p);
3711
3712 TREE_OPERAND (*expr_p, 0) = val;
3713 SAVE_EXPR_RESOLVED_P (*expr_p) = 1;
3714 }
3715
3716 *expr_p = val;
3717
3718 return ret;
3719 }
3720
3721 /* Re-write the ADDR_EXPR node pointed to by EXPR_P
3722
3723 unary_expr
3724 : ...
3725 | '&' varname
3726 ...
3727
3728 PRE_P points to the list where side effects that must happen before
3729 *EXPR_P should be stored.
3730
3731 POST_P points to the list where side effects that must happen after
3732 *EXPR_P should be stored. */
3733
3734 static enum gimplify_status
3735 gimplify_addr_expr (tree *expr_p, tree *pre_p, tree *post_p)
3736 {
3737 tree expr = *expr_p;
3738 tree op0 = TREE_OPERAND (expr, 0);
3739 enum gimplify_status ret;
3740
3741 switch (TREE_CODE (op0))
3742 {
3743 case INDIRECT_REF:
3744 case MISALIGNED_INDIRECT_REF:
3745 do_indirect_ref:
3746 /* Check if we are dealing with an expression of the form '&*ptr'.
3747 While the front end folds away '&*ptr' into 'ptr', these
3748 expressions may be generated internally by the compiler (e.g.,
3749 builtins like __builtin_va_end). */
3750 /* Caution: the silent array decomposition semantics we allow for
3751 ADDR_EXPR means we can't always discard the pair. */
3752 /* Gimplification of the ADDR_EXPR operand may drop
3753 cv-qualification conversions, so make sure we add them if
3754 needed. */
3755 {
3756 tree op00 = TREE_OPERAND (op0, 0);
3757 tree t_expr = TREE_TYPE (expr);
3758 tree t_op00 = TREE_TYPE (op00);
3759
3760 if (!lang_hooks.types_compatible_p (t_expr, t_op00))
3761 {
3762 #ifdef ENABLE_CHECKING
3763 tree t_op0 = TREE_TYPE (op0);
3764 gcc_assert (POINTER_TYPE_P (t_expr)
3765 && cpt_same_type (TREE_CODE (t_op0) == ARRAY_TYPE
3766 ? TREE_TYPE (t_op0) : t_op0,
3767 TREE_TYPE (t_expr))
3768 && POINTER_TYPE_P (t_op00)
3769 && cpt_same_type (t_op0, TREE_TYPE (t_op00)));
3770 #endif
3771 op00 = fold_convert (TREE_TYPE (expr), op00);
3772 }
3773 *expr_p = op00;
3774 ret = GS_OK;
3775 }
3776 break;
3777
3778 case VIEW_CONVERT_EXPR:
3779 /* Take the address of our operand and then convert it to the type of
3780 this ADDR_EXPR.
3781
3782 ??? The interactions of VIEW_CONVERT_EXPR and aliasing is not at
3783 all clear. The impact of this transformation is even less clear. */
3784
3785 /* If the operand is a useless conversion, look through it. Doing so
3786 guarantees that the ADDR_EXPR and its operand will remain of the
3787 same type. */
3788 if (tree_ssa_useless_type_conversion (TREE_OPERAND (op0, 0)))
3789 op0 = TREE_OPERAND (op0, 0);
3790
3791 *expr_p = fold_convert (TREE_TYPE (expr),
3792 build_fold_addr_expr (TREE_OPERAND (op0, 0)));
3793 ret = GS_OK;
3794 break;
3795
3796 default:
3797 /* We use fb_either here because the C frontend sometimes takes
3798 the address of a call that returns a struct; see
3799 gcc.dg/c99-array-lval-1.c. The gimplifier will correctly make
3800 the implied temporary explicit. */
3801 ret = gimplify_expr (&TREE_OPERAND (expr, 0), pre_p, post_p,
3802 is_gimple_addressable, fb_either);
3803 if (ret != GS_ERROR)
3804 {
3805 op0 = TREE_OPERAND (expr, 0);
3806
3807 /* For various reasons, the gimplification of the expression
3808 may have made a new INDIRECT_REF. */
3809 if (TREE_CODE (op0) == INDIRECT_REF)
3810 goto do_indirect_ref;
3811
3812 /* Make sure TREE_INVARIANT, TREE_CONSTANT, and TREE_SIDE_EFFECTS
3813 is set properly. */
3814 recompute_tree_invariant_for_addr_expr (expr);
3815
3816 /* Mark the RHS addressable. */
3817 lang_hooks.mark_addressable (TREE_OPERAND (expr, 0));
3818 }
3819 break;
3820 }
3821
3822 return ret;
3823 }
3824
3825 /* Gimplify the operands of an ASM_EXPR. Input operands should be a gimple
3826 value; output operands should be a gimple lvalue. */
3827
3828 static enum gimplify_status
3829 gimplify_asm_expr (tree *expr_p, tree *pre_p, tree *post_p)
3830 {
3831 tree expr = *expr_p;
3832 int noutputs = list_length (ASM_OUTPUTS (expr));
3833 const char **oconstraints
3834 = (const char **) alloca ((noutputs) * sizeof (const char *));
3835 int i;
3836 tree link;
3837 const char *constraint;
3838 bool allows_mem, allows_reg, is_inout;
3839 enum gimplify_status ret, tret;
3840
3841 ret = GS_ALL_DONE;
3842 for (i = 0, link = ASM_OUTPUTS (expr); link; ++i, link = TREE_CHAIN (link))
3843 {
3844 size_t constraint_len;
3845 oconstraints[i] = constraint
3846 = TREE_STRING_POINTER (TREE_VALUE (TREE_PURPOSE (link)));
3847 constraint_len = strlen (constraint);
3848 if (constraint_len == 0)
3849 continue;
3850
3851 parse_output_constraint (&constraint, i, 0, 0,
3852 &allows_mem, &allows_reg, &is_inout);
3853
3854 if (!allows_reg && allows_mem)
3855 lang_hooks.mark_addressable (TREE_VALUE (link));
3856
3857 tret = gimplify_expr (&TREE_VALUE (link), pre_p, post_p,
3858 is_inout ? is_gimple_min_lval : is_gimple_lvalue,
3859 fb_lvalue | fb_mayfail);
3860 if (tret == GS_ERROR)
3861 {
3862 error ("invalid lvalue in asm output %d", i);
3863 ret = tret;
3864 }
3865
3866 if (is_inout)
3867 {
3868 /* An input/output operand. To give the optimizers more
3869 flexibility, split it into separate input and output
3870 operands. */
3871 tree input;
3872 char buf[10];
3873
3874 /* Turn the in/out constraint into an output constraint. */
3875 char *p = xstrdup (constraint);
3876 p[0] = '=';
3877 TREE_VALUE (TREE_PURPOSE (link)) = build_string (constraint_len, p);
3878
3879 /* And add a matching input constraint. */
3880 if (allows_reg)
3881 {
3882 sprintf (buf, "%d", i);
3883
3884 /* If there are multiple alternatives in the constraint,
3885 handle each of them individually. Those that allow register
3886 will be replaced with operand number, the others will stay
3887 unchanged. */
3888 if (strchr (p, ',') != NULL)
3889 {
3890 size_t len = 0, buflen = strlen (buf);
3891 char *beg, *end, *str, *dst;
3892
3893 for (beg = p + 1;;)
3894 {
3895 end = strchr (beg, ',');
3896 if (end == NULL)
3897 end = strchr (beg, '\0');
3898 if ((size_t) (end - beg) < buflen)
3899 len += buflen + 1;
3900 else
3901 len += end - beg + 1;
3902 if (*end)
3903 beg = end + 1;
3904 else
3905 break;
3906 }
3907
3908 str = (char *) alloca (len);
3909 for (beg = p + 1, dst = str;;)
3910 {
3911 const char *tem;
3912 bool mem_p, reg_p, inout_p;
3913
3914 end = strchr (beg, ',');
3915 if (end)
3916 *end = '\0';
3917 beg[-1] = '=';
3918 tem = beg - 1;
3919 parse_output_constraint (&tem, i, 0, 0,
3920 &mem_p, &reg_p, &inout_p);
3921 if (dst != str)
3922 *dst++ = ',';
3923 if (reg_p)
3924 {
3925 memcpy (dst, buf, buflen);
3926 dst += buflen;
3927 }
3928 else
3929 {
3930 if (end)
3931 len = end - beg;
3932 else
3933 len = strlen (beg);
3934 memcpy (dst, beg, len);
3935 dst += len;
3936 }
3937 if (end)
3938 beg = end + 1;
3939 else
3940 break;
3941 }
3942 *dst = '\0';
3943 input = build_string (dst - str, str);
3944 }
3945 else
3946 input = build_string (strlen (buf), buf);
3947 }
3948 else
3949 input = build_string (constraint_len - 1, constraint + 1);
3950
3951 free (p);
3952
3953 input = build_tree_list (build_tree_list (NULL_TREE, input),
3954 unshare_expr (TREE_VALUE (link)));
3955 ASM_INPUTS (expr) = chainon (ASM_INPUTS (expr), input);
3956 }
3957 }
3958
3959 for (link = ASM_INPUTS (expr); link; ++i, link = TREE_CHAIN (link))
3960 {
3961 constraint
3962 = TREE_STRING_POINTER (TREE_VALUE (TREE_PURPOSE (link)));
3963 parse_input_constraint (&constraint, 0, 0, noutputs, 0,
3964 oconstraints, &allows_mem, &allows_reg);
3965
3966 /* If the operand is a memory input, it should be an lvalue. */
3967 if (!allows_reg && allows_mem)
3968 {
3969 lang_hooks.mark_addressable (TREE_VALUE (link));
3970 tret = gimplify_expr (&TREE_VALUE (link), pre_p, post_p,
3971 is_gimple_lvalue, fb_lvalue | fb_mayfail);
3972 if (tret == GS_ERROR)
3973 {
3974 error ("memory input %d is not directly addressable", i);
3975 ret = tret;
3976 }
3977 }
3978 else
3979 {
3980 tret = gimplify_expr (&TREE_VALUE (link), pre_p, post_p,
3981 is_gimple_asm_val, fb_rvalue);
3982 if (tret == GS_ERROR)
3983 ret = tret;
3984 }
3985 }
3986
3987 return ret;
3988 }
3989
3990 /* Gimplify a CLEANUP_POINT_EXPR. Currently this works by adding
3991 WITH_CLEANUP_EXPRs to the prequeue as we encounter cleanups while
3992 gimplifying the body, and converting them to TRY_FINALLY_EXPRs when we
3993 return to this function.
3994
3995 FIXME should we complexify the prequeue handling instead? Or use flags
3996 for all the cleanups and let the optimizer tighten them up? The current
3997 code seems pretty fragile; it will break on a cleanup within any
3998 non-conditional nesting. But any such nesting would be broken, anyway;
3999 we can't write a TRY_FINALLY_EXPR that starts inside a nesting construct
4000 and continues out of it. We can do that at the RTL level, though, so
4001 having an optimizer to tighten up try/finally regions would be a Good
4002 Thing. */
4003
4004 static enum gimplify_status
4005 gimplify_cleanup_point_expr (tree *expr_p, tree *pre_p)
4006 {
4007 tree_stmt_iterator iter;
4008 tree body;
4009
4010 tree temp = voidify_wrapper_expr (*expr_p, NULL);
4011
4012 /* We only care about the number of conditions between the innermost
4013 CLEANUP_POINT_EXPR and the cleanup. So save and reset the count and
4014 any cleanups collected outside the CLEANUP_POINT_EXPR. */
4015 int old_conds = gimplify_ctxp->conditions;
4016 tree old_cleanups = gimplify_ctxp->conditional_cleanups;
4017 gimplify_ctxp->conditions = 0;
4018 gimplify_ctxp->conditional_cleanups = NULL_TREE;
4019
4020 body = TREE_OPERAND (*expr_p, 0);
4021 gimplify_to_stmt_list (&body);
4022
4023 gimplify_ctxp->conditions = old_conds;
4024 gimplify_ctxp->conditional_cleanups = old_cleanups;
4025
4026 for (iter = tsi_start (body); !tsi_end_p (iter); )
4027 {
4028 tree *wce_p = tsi_stmt_ptr (iter);
4029 tree wce = *wce_p;
4030
4031 if (TREE_CODE (wce) == WITH_CLEANUP_EXPR)
4032 {
4033 if (tsi_one_before_end_p (iter))
4034 {
4035 tsi_link_before (&iter, TREE_OPERAND (wce, 0), TSI_SAME_STMT);
4036 tsi_delink (&iter);
4037 break;
4038 }
4039 else
4040 {
4041 tree sl, tfe;
4042 enum tree_code code;
4043
4044 if (CLEANUP_EH_ONLY (wce))
4045 code = TRY_CATCH_EXPR;
4046 else
4047 code = TRY_FINALLY_EXPR;
4048
4049 sl = tsi_split_statement_list_after (&iter);
4050 tfe = build2 (code, void_type_node, sl, NULL_TREE);
4051 append_to_statement_list (TREE_OPERAND (wce, 0),
4052 &TREE_OPERAND (tfe, 1));
4053 *wce_p = tfe;
4054 iter = tsi_start (sl);
4055 }
4056 }
4057 else
4058 tsi_next (&iter);
4059 }
4060
4061 if (temp)
4062 {
4063 *expr_p = temp;
4064 append_to_statement_list (body, pre_p);
4065 return GS_OK;
4066 }
4067 else
4068 {
4069 *expr_p = body;
4070 return GS_ALL_DONE;
4071 }
4072 }
4073
4074 /* Insert a cleanup marker for gimplify_cleanup_point_expr. CLEANUP
4075 is the cleanup action required. */
4076
4077 static void
4078 gimple_push_cleanup (tree var, tree cleanup, bool eh_only, tree *pre_p)
4079 {
4080 tree wce;
4081
4082 /* Errors can result in improperly nested cleanups. Which results in
4083 confusion when trying to resolve the WITH_CLEANUP_EXPR. */
4084 if (errorcount || sorrycount)
4085 return;
4086
4087 if (gimple_conditional_context ())
4088 {
4089 /* If we're in a conditional context, this is more complex. We only
4090 want to run the cleanup if we actually ran the initialization that
4091 necessitates it, but we want to run it after the end of the
4092 conditional context. So we wrap the try/finally around the
4093 condition and use a flag to determine whether or not to actually
4094 run the destructor. Thus
4095
4096 test ? f(A()) : 0
4097
4098 becomes (approximately)
4099
4100 flag = 0;
4101 try {
4102 if (test) { A::A(temp); flag = 1; val = f(temp); }
4103 else { val = 0; }
4104 } finally {
4105 if (flag) A::~A(temp);
4106 }
4107 val
4108 */
4109
4110 tree flag = create_tmp_var (boolean_type_node, "cleanup");
4111 tree ffalse = build2 (MODIFY_EXPR, void_type_node, flag,
4112 boolean_false_node);
4113 tree ftrue = build2 (MODIFY_EXPR, void_type_node, flag,
4114 boolean_true_node);
4115 cleanup = build3 (COND_EXPR, void_type_node, flag, cleanup, NULL);
4116 wce = build1 (WITH_CLEANUP_EXPR, void_type_node, cleanup);
4117 append_to_statement_list (ffalse, &gimplify_ctxp->conditional_cleanups);
4118 append_to_statement_list (wce, &gimplify_ctxp->conditional_cleanups);
4119 append_to_statement_list (ftrue, pre_p);
4120
4121 /* Because of this manipulation, and the EH edges that jump
4122 threading cannot redirect, the temporary (VAR) will appear
4123 to be used uninitialized. Don't warn. */
4124 TREE_NO_WARNING (var) = 1;
4125 }
4126 else
4127 {
4128 wce = build1 (WITH_CLEANUP_EXPR, void_type_node, cleanup);
4129 CLEANUP_EH_ONLY (wce) = eh_only;
4130 append_to_statement_list (wce, pre_p);
4131 }
4132
4133 gimplify_stmt (&TREE_OPERAND (wce, 0));
4134 }
4135
4136 /* Gimplify a TARGET_EXPR which doesn't appear on the rhs of an INIT_EXPR. */
4137
4138 static enum gimplify_status
4139 gimplify_target_expr (tree *expr_p, tree *pre_p, tree *post_p)
4140 {
4141 tree targ = *expr_p;
4142 tree temp = TARGET_EXPR_SLOT (targ);
4143 tree init = TARGET_EXPR_INITIAL (targ);
4144 enum gimplify_status ret;
4145
4146 if (init)
4147 {
4148 /* TARGET_EXPR temps aren't part of the enclosing block, so add it
4149 to the temps list. */
4150 gimple_add_tmp_var (temp);
4151
4152 /* If TARGET_EXPR_INITIAL is void, then the mere evaluation of the
4153 expression is supposed to initialize the slot. */
4154 if (VOID_TYPE_P (TREE_TYPE (init)))
4155 ret = gimplify_expr (&init, pre_p, post_p, is_gimple_stmt, fb_none);
4156 else
4157 {
4158 /* Special handling for BIND_EXPR can result in fewer temps. */
4159 ret = GS_OK;
4160 if (TREE_CODE (init) == BIND_EXPR)
4161 gimplify_bind_expr (&init, temp, pre_p);
4162 if (init != temp)
4163 {
4164 init = build2 (INIT_EXPR, void_type_node, temp, init);
4165 ret = gimplify_expr (&init, pre_p, post_p, is_gimple_stmt,
4166 fb_none);
4167 }
4168 }
4169 if (ret == GS_ERROR)
4170 return GS_ERROR;
4171 append_to_statement_list (init, pre_p);
4172
4173 /* If needed, push the cleanup for the temp. */
4174 if (TARGET_EXPR_CLEANUP (targ))
4175 {
4176 gimplify_stmt (&TARGET_EXPR_CLEANUP (targ));
4177 gimple_push_cleanup (temp, TARGET_EXPR_CLEANUP (targ),
4178 CLEANUP_EH_ONLY (targ), pre_p);
4179 }
4180
4181 /* Only expand this once. */
4182 TREE_OPERAND (targ, 3) = init;
4183 TARGET_EXPR_INITIAL (targ) = NULL_TREE;
4184 }
4185 else
4186 /* We should have expanded this before. */
4187 gcc_assert (DECL_SEEN_IN_BIND_EXPR_P (temp));
4188
4189 *expr_p = temp;
4190 return GS_OK;
4191 }
4192
4193 /* Gimplification of expression trees. */
4194
4195 /* Gimplify an expression which appears at statement context; usually, this
4196 means replacing it with a suitably gimple STATEMENT_LIST. */
4197
4198 void
4199 gimplify_stmt (tree *stmt_p)
4200 {
4201 gimplify_expr (stmt_p, NULL, NULL, is_gimple_stmt, fb_none);
4202 }
4203
4204 /* Similarly, but force the result to be a STATEMENT_LIST. */
4205
4206 void
4207 gimplify_to_stmt_list (tree *stmt_p)
4208 {
4209 gimplify_stmt (stmt_p);
4210 if (!*stmt_p)
4211 *stmt_p = alloc_stmt_list ();
4212 else if (TREE_CODE (*stmt_p) != STATEMENT_LIST)
4213 {
4214 tree t = *stmt_p;
4215 *stmt_p = alloc_stmt_list ();
4216 append_to_statement_list (t, stmt_p);
4217 }
4218 }
4219
4220
4221 /* Add FIRSTPRIVATE entries for DECL in the OpenMP the surrounding parallels
4222 to CTX. If entries already exist, force them to be some flavor of private.
4223 If there is no enclosing parallel, do nothing. */
4224
4225 void
4226 omp_firstprivatize_variable (struct gimplify_omp_ctx *ctx, tree decl)
4227 {
4228 splay_tree_node n;
4229
4230 if (decl == NULL || !DECL_P (decl))
4231 return;
4232
4233 do
4234 {
4235 n = splay_tree_lookup (ctx->variables, (splay_tree_key)decl);
4236 if (n != NULL)
4237 {
4238 if (n->value & GOVD_SHARED)
4239 n->value = GOVD_FIRSTPRIVATE | (n->value & GOVD_SEEN);
4240 else
4241 return;
4242 }
4243 else if (ctx->is_parallel)
4244 omp_add_variable (ctx, decl, GOVD_FIRSTPRIVATE);
4245
4246 ctx = ctx->outer_context;
4247 }
4248 while (ctx);
4249 }
4250
4251 /* Similarly for each of the type sizes of TYPE. */
4252
4253 static void
4254 omp_firstprivatize_type_sizes (struct gimplify_omp_ctx *ctx, tree type)
4255 {
4256 if (type == NULL || type == error_mark_node)
4257 return;
4258 type = TYPE_MAIN_VARIANT (type);
4259
4260 if (pointer_set_insert (ctx->privatized_types, type))
4261 return;
4262
4263 switch (TREE_CODE (type))
4264 {
4265 case INTEGER_TYPE:
4266 case ENUMERAL_TYPE:
4267 case BOOLEAN_TYPE:
4268 case REAL_TYPE:
4269 omp_firstprivatize_variable (ctx, TYPE_MIN_VALUE (type));
4270 omp_firstprivatize_variable (ctx, TYPE_MAX_VALUE (type));
4271 break;
4272
4273 case ARRAY_TYPE:
4274 omp_firstprivatize_type_sizes (ctx, TREE_TYPE (type));
4275 omp_firstprivatize_type_sizes (ctx, TYPE_DOMAIN (type));
4276 break;
4277
4278 case RECORD_TYPE:
4279 case UNION_TYPE:
4280 case QUAL_UNION_TYPE:
4281 {
4282 tree field;
4283 for (field = TYPE_FIELDS (type); field; field = TREE_CHAIN (field))
4284 if (TREE_CODE (field) == FIELD_DECL)
4285 {
4286 omp_firstprivatize_variable (ctx, DECL_FIELD_OFFSET (field));
4287 omp_firstprivatize_type_sizes (ctx, TREE_TYPE (field));
4288 }
4289 }
4290 break;
4291
4292 case POINTER_TYPE:
4293 case REFERENCE_TYPE:
4294 omp_firstprivatize_type_sizes (ctx, TREE_TYPE (type));
4295 break;
4296
4297 default:
4298 break;
4299 }
4300
4301 omp_firstprivatize_variable (ctx, TYPE_SIZE (type));
4302 omp_firstprivatize_variable (ctx, TYPE_SIZE_UNIT (type));
4303 lang_hooks.types.omp_firstprivatize_type_sizes (ctx, type);
4304 }
4305
4306 /* Add an entry for DECL in the OpenMP context CTX with FLAGS. */
4307
4308 static void
4309 omp_add_variable (struct gimplify_omp_ctx *ctx, tree decl, unsigned int flags)
4310 {
4311 splay_tree_node n;
4312 unsigned int nflags;
4313 tree t;
4314
4315 if (decl == error_mark_node || TREE_TYPE (decl) == error_mark_node)
4316 return;
4317
4318 /* Never elide decls whose type has TREE_ADDRESSABLE set. This means
4319 there are constructors involved somewhere. */
4320 if (TREE_ADDRESSABLE (TREE_TYPE (decl))
4321 || TYPE_NEEDS_CONSTRUCTING (TREE_TYPE (decl)))
4322 flags |= GOVD_SEEN;
4323
4324 n = splay_tree_lookup (ctx->variables, (splay_tree_key)decl);
4325 if (n != NULL)
4326 {
4327 /* We shouldn't be re-adding the decl with the same data
4328 sharing class. */
4329 gcc_assert ((n->value & GOVD_DATA_SHARE_CLASS & flags) == 0);
4330 /* The only combination of data sharing classes we should see is
4331 FIRSTPRIVATE and LASTPRIVATE. */
4332 nflags = n->value | flags;
4333 gcc_assert ((nflags & GOVD_DATA_SHARE_CLASS)
4334 == (GOVD_FIRSTPRIVATE | GOVD_LASTPRIVATE));
4335 n->value = nflags;
4336 return;
4337 }
4338
4339 /* When adding a variable-sized variable, we have to handle all sorts
4340 of additional bits of data: the pointer replacement variable, and
4341 the parameters of the type. */
4342 if (DECL_SIZE (decl) && !TREE_CONSTANT (DECL_SIZE (decl)))
4343 {
4344 /* Add the pointer replacement variable as PRIVATE if the variable
4345 replacement is private, else FIRSTPRIVATE since we'll need the
4346 address of the original variable either for SHARED, or for the
4347 copy into or out of the context. */
4348 if (!(flags & GOVD_LOCAL))
4349 {
4350 nflags = flags & GOVD_PRIVATE ? GOVD_PRIVATE : GOVD_FIRSTPRIVATE;
4351 nflags |= flags & GOVD_SEEN;
4352 t = DECL_VALUE_EXPR (decl);
4353 gcc_assert (TREE_CODE (t) == INDIRECT_REF);
4354 t = TREE_OPERAND (t, 0);
4355 gcc_assert (DECL_P (t));
4356 omp_add_variable (ctx, t, nflags);
4357 }
4358
4359 /* Add all of the variable and type parameters (which should have
4360 been gimplified to a formal temporary) as FIRSTPRIVATE. */
4361 omp_firstprivatize_variable (ctx, DECL_SIZE_UNIT (decl));
4362 omp_firstprivatize_variable (ctx, DECL_SIZE (decl));
4363 omp_firstprivatize_type_sizes (ctx, TREE_TYPE (decl));
4364
4365 /* The variable-sized variable itself is never SHARED, only some form
4366 of PRIVATE. The sharing would take place via the pointer variable
4367 which we remapped above. */
4368 if (flags & GOVD_SHARED)
4369 flags = GOVD_PRIVATE | GOVD_DEBUG_PRIVATE
4370 | (flags & (GOVD_SEEN | GOVD_EXPLICIT));
4371
4372 /* We're going to make use of the TYPE_SIZE_UNIT at least in the
4373 alloca statement we generate for the variable, so make sure it
4374 is available. This isn't automatically needed for the SHARED
4375 case, since we won't be allocating local storage then. */
4376 else
4377 omp_notice_variable (ctx, TYPE_SIZE_UNIT (TREE_TYPE (decl)), true);
4378 }
4379 else if (lang_hooks.decls.omp_privatize_by_reference (decl))
4380 {
4381 gcc_assert ((flags & GOVD_LOCAL) == 0);
4382 omp_firstprivatize_type_sizes (ctx, TREE_TYPE (decl));
4383
4384 /* Similar to the direct variable sized case above, we'll need the
4385 size of references being privatized. */
4386 if ((flags & GOVD_SHARED) == 0)
4387 {
4388 t = TYPE_SIZE_UNIT (TREE_TYPE (TREE_TYPE (decl)));
4389 if (!TREE_CONSTANT (t))
4390 omp_notice_variable (ctx, t, true);
4391 }
4392 }
4393
4394 splay_tree_insert (ctx->variables, (splay_tree_key)decl, flags);
4395 }
4396
4397 /* Record the fact that DECL was used within the OpenMP context CTX.
4398 IN_CODE is true when real code uses DECL, and false when we should
4399 merely emit default(none) errors. Return true if DECL is going to
4400 be remapped and thus DECL shouldn't be gimplified into its
4401 DECL_VALUE_EXPR (if any). */
4402
4403 static bool
4404 omp_notice_variable (struct gimplify_omp_ctx *ctx, tree decl, bool in_code)
4405 {
4406 splay_tree_node n;
4407 unsigned flags = in_code ? GOVD_SEEN : 0;
4408 bool ret = false, shared;
4409
4410 if (decl == error_mark_node || TREE_TYPE (decl) == error_mark_node)
4411 return false;
4412
4413 /* Threadprivate variables are predetermined. */
4414 if (is_global_var (decl))
4415 {
4416 if (DECL_THREAD_LOCAL_P (decl))
4417 return false;
4418
4419 if (DECL_HAS_VALUE_EXPR_P (decl))
4420 {
4421 tree value = get_base_address (DECL_VALUE_EXPR (decl));
4422
4423 if (value && DECL_P (value) && DECL_THREAD_LOCAL_P (value))
4424 return false;
4425 }
4426 }
4427
4428 n = splay_tree_lookup (ctx->variables, (splay_tree_key)decl);
4429 if (n == NULL)
4430 {
4431 enum omp_clause_default_kind default_kind, kind;
4432
4433 if (!ctx->is_parallel)
4434 goto do_outer;
4435
4436 /* ??? Some compiler-generated variables (like SAVE_EXPRs) could be
4437 remapped firstprivate instead of shared. To some extent this is
4438 addressed in omp_firstprivatize_type_sizes, but not effectively. */
4439 default_kind = ctx->default_kind;
4440 kind = lang_hooks.decls.omp_predetermined_sharing (decl);
4441 if (kind != OMP_CLAUSE_DEFAULT_UNSPECIFIED)
4442 default_kind = kind;
4443
4444 switch (default_kind)
4445 {
4446 case OMP_CLAUSE_DEFAULT_NONE:
4447 error ("%qs not specified in enclosing parallel",
4448 IDENTIFIER_POINTER (DECL_NAME (decl)));
4449 error ("%Henclosing parallel", &ctx->location);
4450 /* FALLTHRU */
4451 case OMP_CLAUSE_DEFAULT_SHARED:
4452 flags |= GOVD_SHARED;
4453 break;
4454 case OMP_CLAUSE_DEFAULT_PRIVATE:
4455 flags |= GOVD_PRIVATE;
4456 break;
4457 default:
4458 gcc_unreachable ();
4459 }
4460
4461 omp_add_variable (ctx, decl, flags);
4462
4463 shared = (flags & GOVD_SHARED) != 0;
4464 ret = lang_hooks.decls.omp_disregard_value_expr (decl, shared);
4465 goto do_outer;
4466 }
4467
4468 shared = ((flags | n->value) & GOVD_SHARED) != 0;
4469 ret = lang_hooks.decls.omp_disregard_value_expr (decl, shared);
4470
4471 /* If nothing changed, there's nothing left to do. */
4472 if ((n->value & flags) == flags)
4473 return ret;
4474 flags |= n->value;
4475 n->value = flags;
4476
4477 do_outer:
4478 /* If the variable is private in the current context, then we don't
4479 need to propagate anything to an outer context. */
4480 if (flags & GOVD_PRIVATE)
4481 return ret;
4482 if (ctx->outer_context
4483 && omp_notice_variable (ctx->outer_context, decl, in_code))
4484 return true;
4485 return ret;
4486 }
4487
4488 /* Verify that DECL is private within CTX. If there's specific information
4489 to the contrary in the innermost scope, generate an error. */
4490
4491 static bool
4492 omp_is_private (struct gimplify_omp_ctx *ctx, tree decl)
4493 {
4494 splay_tree_node n;
4495
4496 n = splay_tree_lookup (ctx->variables, (splay_tree_key)decl);
4497 if (n != NULL)
4498 {
4499 if (n->value & GOVD_SHARED)
4500 {
4501 if (ctx == gimplify_omp_ctxp)
4502 {
4503 error ("iteration variable %qs should be private",
4504 IDENTIFIER_POINTER (DECL_NAME (decl)));
4505 n->value = GOVD_PRIVATE;
4506 return true;
4507 }
4508 else
4509 return false;
4510 }
4511 else if ((n->value & GOVD_EXPLICIT) != 0
4512 && (ctx == gimplify_omp_ctxp
4513 || (ctx->is_combined_parallel
4514 && gimplify_omp_ctxp->outer_context == ctx)))
4515 {
4516 if ((n->value & GOVD_FIRSTPRIVATE) != 0)
4517 error ("iteration variable %qs should not be firstprivate",
4518 IDENTIFIER_POINTER (DECL_NAME (decl)));
4519 else if ((n->value & GOVD_REDUCTION) != 0)
4520 error ("iteration variable %qs should not be reduction",
4521 IDENTIFIER_POINTER (DECL_NAME (decl)));
4522 }
4523 return true;
4524 }
4525
4526 if (ctx->is_parallel)
4527 return false;
4528 else if (ctx->outer_context)
4529 return omp_is_private (ctx->outer_context, decl);
4530 else
4531 return !is_global_var (decl);
4532 }
4533
4534 /* Scan the OpenMP clauses in *LIST_P, installing mappings into a new
4535 and previous omp contexts. */
4536
4537 static void
4538 gimplify_scan_omp_clauses (tree *list_p, tree *pre_p, bool in_parallel,
4539 bool in_combined_parallel)
4540 {
4541 struct gimplify_omp_ctx *ctx, *outer_ctx;
4542 tree c;
4543
4544 ctx = new_omp_context (in_parallel, in_combined_parallel);
4545 outer_ctx = ctx->outer_context;
4546
4547 while ((c = *list_p) != NULL)
4548 {
4549 enum gimplify_status gs;
4550 bool remove = false;
4551 bool notice_outer = true;
4552 unsigned int flags;
4553 tree decl;
4554
4555 switch (OMP_CLAUSE_CODE (c))
4556 {
4557 case OMP_CLAUSE_PRIVATE:
4558 flags = GOVD_PRIVATE | GOVD_EXPLICIT;
4559 notice_outer = false;
4560 goto do_add;
4561 case OMP_CLAUSE_SHARED:
4562 flags = GOVD_SHARED | GOVD_EXPLICIT;
4563 goto do_add;
4564 case OMP_CLAUSE_FIRSTPRIVATE:
4565 flags = GOVD_FIRSTPRIVATE | GOVD_EXPLICIT;
4566 goto do_add;
4567 case OMP_CLAUSE_LASTPRIVATE:
4568 flags = GOVD_LASTPRIVATE | GOVD_SEEN | GOVD_EXPLICIT;
4569 goto do_add;
4570 case OMP_CLAUSE_REDUCTION:
4571 flags = GOVD_REDUCTION | GOVD_SEEN | GOVD_EXPLICIT;
4572 goto do_add;
4573
4574 do_add:
4575 decl = OMP_CLAUSE_DECL (c);
4576 if (decl == error_mark_node || TREE_TYPE (decl) == error_mark_node)
4577 {
4578 remove = true;
4579 break;
4580 }
4581 /* Handle NRV results passed by reference. */
4582 if (TREE_CODE (decl) == INDIRECT_REF
4583 && TREE_CODE (TREE_OPERAND (decl, 0)) == RESULT_DECL
4584 && DECL_BY_REFERENCE (TREE_OPERAND (decl, 0)))
4585 OMP_CLAUSE_DECL (c) = decl = TREE_OPERAND (decl, 0);
4586 omp_add_variable (ctx, decl, flags);
4587 if (OMP_CLAUSE_CODE (c) == OMP_CLAUSE_REDUCTION
4588 && OMP_CLAUSE_REDUCTION_PLACEHOLDER (c))
4589 {
4590 omp_add_variable (ctx, OMP_CLAUSE_REDUCTION_PLACEHOLDER (c),
4591 GOVD_LOCAL | GOVD_SEEN);
4592 gimplify_omp_ctxp = ctx;
4593 push_gimplify_context ();
4594 gimplify_stmt (&OMP_CLAUSE_REDUCTION_INIT (c));
4595 pop_gimplify_context (OMP_CLAUSE_REDUCTION_INIT (c));
4596 push_gimplify_context ();
4597 gimplify_stmt (&OMP_CLAUSE_REDUCTION_MERGE (c));
4598 pop_gimplify_context (OMP_CLAUSE_REDUCTION_MERGE (c));
4599 gimplify_omp_ctxp = outer_ctx;
4600 }
4601 if (notice_outer)
4602 goto do_notice;
4603 break;
4604
4605 case OMP_CLAUSE_COPYIN:
4606 case OMP_CLAUSE_COPYPRIVATE:
4607 decl = OMP_CLAUSE_DECL (c);
4608 if (decl == error_mark_node || TREE_TYPE (decl) == error_mark_node)
4609 {
4610 remove = true;
4611 break;
4612 }
4613 /* Handle NRV results passed by reference. */
4614 if (TREE_CODE (decl) == INDIRECT_REF
4615 && TREE_CODE (TREE_OPERAND (decl, 0)) == RESULT_DECL
4616 && DECL_BY_REFERENCE (TREE_OPERAND (decl, 0)))
4617 OMP_CLAUSE_DECL (c) = decl = TREE_OPERAND (decl, 0);
4618 do_notice:
4619 if (outer_ctx)
4620 omp_notice_variable (outer_ctx, decl, true);
4621 break;
4622
4623 case OMP_CLAUSE_IF:
4624 OMP_CLAUSE_OPERAND (c, 0)
4625 = gimple_boolify (OMP_CLAUSE_OPERAND (c, 0));
4626 /* Fall through. */
4627
4628 case OMP_CLAUSE_SCHEDULE:
4629 case OMP_CLAUSE_NUM_THREADS:
4630 gs = gimplify_expr (&OMP_CLAUSE_OPERAND (c, 0), pre_p, NULL,
4631 is_gimple_val, fb_rvalue);
4632 if (gs == GS_ERROR)
4633 remove = true;
4634 break;
4635
4636 case OMP_CLAUSE_NOWAIT:
4637 case OMP_CLAUSE_ORDERED:
4638 break;
4639
4640 case OMP_CLAUSE_DEFAULT:
4641 ctx->default_kind = OMP_CLAUSE_DEFAULT_KIND (c);
4642 break;
4643
4644 default:
4645 gcc_unreachable ();
4646 }
4647
4648 if (remove)
4649 *list_p = OMP_CLAUSE_CHAIN (c);
4650 else
4651 list_p = &OMP_CLAUSE_CHAIN (c);
4652 }
4653
4654 gimplify_omp_ctxp = ctx;
4655 }
4656
4657 /* For all variables that were not actually used within the context,
4658 remove PRIVATE, SHARED, and FIRSTPRIVATE clauses. */
4659
4660 static int
4661 gimplify_adjust_omp_clauses_1 (splay_tree_node n, void *data)
4662 {
4663 tree *list_p = (tree *) data;
4664 tree decl = (tree) n->key;
4665 unsigned flags = n->value;
4666 enum omp_clause_code code;
4667 tree clause;
4668 bool private_debug;
4669
4670 if (flags & (GOVD_EXPLICIT | GOVD_LOCAL))
4671 return 0;
4672 if ((flags & GOVD_SEEN) == 0)
4673 return 0;
4674 if (flags & GOVD_DEBUG_PRIVATE)
4675 {
4676 gcc_assert ((flags & GOVD_DATA_SHARE_CLASS) == GOVD_PRIVATE);
4677 private_debug = true;
4678 }
4679 else
4680 private_debug
4681 = lang_hooks.decls.omp_private_debug_clause (decl,
4682 !!(flags & GOVD_SHARED));
4683 if (private_debug)
4684 code = OMP_CLAUSE_PRIVATE;
4685 else if (flags & GOVD_SHARED)
4686 {
4687 if (is_global_var (decl))
4688 return 0;
4689 code = OMP_CLAUSE_SHARED;
4690 }
4691 else if (flags & GOVD_PRIVATE)
4692 code = OMP_CLAUSE_PRIVATE;
4693 else if (flags & GOVD_FIRSTPRIVATE)
4694 code = OMP_CLAUSE_FIRSTPRIVATE;
4695 else
4696 gcc_unreachable ();
4697
4698 clause = build_omp_clause (code);
4699 OMP_CLAUSE_DECL (clause) = decl;
4700 OMP_CLAUSE_CHAIN (clause) = *list_p;
4701 if (private_debug)
4702 OMP_CLAUSE_PRIVATE_DEBUG (clause) = 1;
4703 *list_p = clause;
4704
4705 return 0;
4706 }
4707
4708 static void
4709 gimplify_adjust_omp_clauses (tree *list_p)
4710 {
4711 struct gimplify_omp_ctx *ctx = gimplify_omp_ctxp;
4712 tree c, decl;
4713
4714 while ((c = *list_p) != NULL)
4715 {
4716 splay_tree_node n;
4717 bool remove = false;
4718
4719 switch (OMP_CLAUSE_CODE (c))
4720 {
4721 case OMP_CLAUSE_PRIVATE:
4722 case OMP_CLAUSE_SHARED:
4723 case OMP_CLAUSE_FIRSTPRIVATE:
4724 decl = OMP_CLAUSE_DECL (c);
4725 n = splay_tree_lookup (ctx->variables, (splay_tree_key) decl);
4726 remove = !(n->value & GOVD_SEEN);
4727 if (! remove)
4728 {
4729 bool shared = OMP_CLAUSE_CODE (c) == OMP_CLAUSE_SHARED;
4730 if ((n->value & GOVD_DEBUG_PRIVATE)
4731 || lang_hooks.decls.omp_private_debug_clause (decl, shared))
4732 {
4733 gcc_assert ((n->value & GOVD_DEBUG_PRIVATE) == 0
4734 || ((n->value & GOVD_DATA_SHARE_CLASS)
4735 == GOVD_PRIVATE));
4736 OMP_CLAUSE_SET_CODE (c, OMP_CLAUSE_PRIVATE);
4737 OMP_CLAUSE_PRIVATE_DEBUG (c) = 1;
4738 }
4739 }
4740 break;
4741
4742 case OMP_CLAUSE_LASTPRIVATE:
4743 /* Make sure OMP_CLAUSE_LASTPRIVATE_FIRSTPRIVATE is set to
4744 accurately reflect the presence of a FIRSTPRIVATE clause. */
4745 decl = OMP_CLAUSE_DECL (c);
4746 n = splay_tree_lookup (ctx->variables, (splay_tree_key) decl);
4747 OMP_CLAUSE_LASTPRIVATE_FIRSTPRIVATE (c)
4748 = (n->value & GOVD_FIRSTPRIVATE) != 0;
4749 break;
4750
4751 case OMP_CLAUSE_REDUCTION:
4752 case OMP_CLAUSE_COPYIN:
4753 case OMP_CLAUSE_COPYPRIVATE:
4754 case OMP_CLAUSE_IF:
4755 case OMP_CLAUSE_NUM_THREADS:
4756 case OMP_CLAUSE_SCHEDULE:
4757 case OMP_CLAUSE_NOWAIT:
4758 case OMP_CLAUSE_ORDERED:
4759 case OMP_CLAUSE_DEFAULT:
4760 break;
4761
4762 default:
4763 gcc_unreachable ();
4764 }
4765
4766 if (remove)
4767 *list_p = OMP_CLAUSE_CHAIN (c);
4768 else
4769 list_p = &OMP_CLAUSE_CHAIN (c);
4770 }
4771
4772 /* Add in any implicit data sharing. */
4773 splay_tree_foreach (ctx->variables, gimplify_adjust_omp_clauses_1, list_p);
4774
4775 gimplify_omp_ctxp = ctx->outer_context;
4776 delete_omp_context (ctx);
4777 }
4778
4779 /* Gimplify the contents of an OMP_PARALLEL statement. This involves
4780 gimplification of the body, as well as scanning the body for used
4781 variables. We need to do this scan now, because variable-sized
4782 decls will be decomposed during gimplification. */
4783
4784 static enum gimplify_status
4785 gimplify_omp_parallel (tree *expr_p, tree *pre_p)
4786 {
4787 tree expr = *expr_p;
4788
4789 gimplify_scan_omp_clauses (&OMP_PARALLEL_CLAUSES (expr), pre_p, true,
4790 OMP_PARALLEL_COMBINED (expr));
4791
4792 push_gimplify_context ();
4793
4794 gimplify_stmt (&OMP_PARALLEL_BODY (expr));
4795
4796 if (TREE_CODE (OMP_PARALLEL_BODY (expr)) == BIND_EXPR)
4797 pop_gimplify_context (OMP_PARALLEL_BODY (expr));
4798 else
4799 pop_gimplify_context (NULL_TREE);
4800
4801 gimplify_adjust_omp_clauses (&OMP_PARALLEL_CLAUSES (expr));
4802
4803 return GS_ALL_DONE;
4804 }
4805
4806 /* Gimplify the gross structure of an OMP_FOR statement. */
4807
4808 static enum gimplify_status
4809 gimplify_omp_for (tree *expr_p, tree *pre_p)
4810 {
4811 tree for_stmt, decl, t;
4812 enum gimplify_status ret = 0;
4813
4814 for_stmt = *expr_p;
4815
4816 gimplify_scan_omp_clauses (&OMP_FOR_CLAUSES (for_stmt), pre_p, false, false);
4817
4818 t = OMP_FOR_INIT (for_stmt);
4819 gcc_assert (TREE_CODE (t) == MODIFY_EXPR);
4820 decl = TREE_OPERAND (t, 0);
4821 gcc_assert (DECL_P (decl));
4822 gcc_assert (INTEGRAL_TYPE_P (TREE_TYPE (decl)));
4823
4824 /* Make sure the iteration variable is private. */
4825 if (omp_is_private (gimplify_omp_ctxp, decl))
4826 omp_notice_variable (gimplify_omp_ctxp, decl, true);
4827 else
4828 omp_add_variable (gimplify_omp_ctxp, decl, GOVD_PRIVATE | GOVD_SEEN);
4829
4830 ret |= gimplify_expr (&TREE_OPERAND (t, 1), &OMP_FOR_PRE_BODY (for_stmt),
4831 NULL, is_gimple_val, fb_rvalue);
4832
4833 t = OMP_FOR_COND (for_stmt);
4834 gcc_assert (COMPARISON_CLASS_P (t));
4835 gcc_assert (TREE_OPERAND (t, 0) == decl);
4836
4837 ret |= gimplify_expr (&TREE_OPERAND (t, 1), &OMP_FOR_PRE_BODY (for_stmt),
4838 NULL, is_gimple_val, fb_rvalue);
4839
4840 t = OMP_FOR_INCR (for_stmt);
4841 switch (TREE_CODE (t))
4842 {
4843 case PREINCREMENT_EXPR:
4844 case POSTINCREMENT_EXPR:
4845 t = build_int_cst (TREE_TYPE (decl), 1);
4846 goto build_modify;
4847 case PREDECREMENT_EXPR:
4848 case POSTDECREMENT_EXPR:
4849 t = build_int_cst (TREE_TYPE (decl), -1);
4850 goto build_modify;
4851 build_modify:
4852 t = build2 (PLUS_EXPR, TREE_TYPE (decl), decl, t);
4853 t = build2 (MODIFY_EXPR, void_type_node, decl, t);
4854 OMP_FOR_INCR (for_stmt) = t;
4855 break;
4856
4857 case MODIFY_EXPR:
4858 gcc_assert (TREE_OPERAND (t, 0) == decl);
4859 t = TREE_OPERAND (t, 1);
4860 switch (TREE_CODE (t))
4861 {
4862 case PLUS_EXPR:
4863 if (TREE_OPERAND (t, 1) == decl)
4864 {
4865 TREE_OPERAND (t, 1) = TREE_OPERAND (t, 0);
4866 TREE_OPERAND (t, 0) = decl;
4867 break;
4868 }
4869 case MINUS_EXPR:
4870 gcc_assert (TREE_OPERAND (t, 0) == decl);
4871 break;
4872 default:
4873 gcc_unreachable ();
4874 }
4875
4876 ret |= gimplify_expr (&TREE_OPERAND (t, 1), &OMP_FOR_PRE_BODY (for_stmt),
4877 NULL, is_gimple_val, fb_rvalue);
4878 break;
4879
4880 default:
4881 gcc_unreachable ();
4882 }
4883
4884 gimplify_to_stmt_list (&OMP_FOR_BODY (for_stmt));
4885 gimplify_adjust_omp_clauses (&OMP_FOR_CLAUSES (for_stmt));
4886
4887 return ret == GS_ALL_DONE ? GS_ALL_DONE : GS_ERROR;
4888 }
4889
4890 /* Gimplify the gross structure of other OpenMP worksharing constructs.
4891 In particular, OMP_SECTIONS and OMP_SINGLE. */
4892
4893 static enum gimplify_status
4894 gimplify_omp_workshare (tree *expr_p, tree *pre_p)
4895 {
4896 tree stmt = *expr_p;
4897
4898 gimplify_scan_omp_clauses (&OMP_CLAUSES (stmt), pre_p, false, false);
4899 gimplify_to_stmt_list (&OMP_BODY (stmt));
4900 gimplify_adjust_omp_clauses (&OMP_CLAUSES (stmt));
4901
4902 return GS_ALL_DONE;
4903 }
4904
4905 /* A subroutine of gimplify_omp_atomic. The front end is supposed to have
4906 stabilized the lhs of the atomic operation as *ADDR. Return true if
4907 EXPR is this stabilized form. */
4908
4909 static bool
4910 goa_lhs_expr_p (tree expr, tree addr)
4911 {
4912 /* Also include casts to other type variants. The C front end is fond
4913 of adding these for e.g. volatile variables. This is like
4914 STRIP_TYPE_NOPS but includes the main variant lookup. */
4915 while ((TREE_CODE (expr) == NOP_EXPR
4916 || TREE_CODE (expr) == CONVERT_EXPR
4917 || TREE_CODE (expr) == NON_LVALUE_EXPR)
4918 && TREE_OPERAND (expr, 0) != error_mark_node
4919 && (TYPE_MAIN_VARIANT (TREE_TYPE (expr))
4920 == TYPE_MAIN_VARIANT (TREE_TYPE (TREE_OPERAND (expr, 0)))))
4921 expr = TREE_OPERAND (expr, 0);
4922
4923 if (TREE_CODE (expr) == INDIRECT_REF && TREE_OPERAND (expr, 0) == addr)
4924 return true;
4925 if (TREE_CODE (addr) == ADDR_EXPR && expr == TREE_OPERAND (addr, 0))
4926 return true;
4927 return false;
4928 }
4929
4930 /* A subroutine of gimplify_omp_atomic. Attempt to implement the atomic
4931 operation as a __sync_fetch_and_op builtin. INDEX is log2 of the
4932 size of the data type, and thus usable to find the index of the builtin
4933 decl. Returns GS_UNHANDLED if the expression is not of the proper form. */
4934
4935 static enum gimplify_status
4936 gimplify_omp_atomic_fetch_op (tree *expr_p, tree addr, tree rhs, int index)
4937 {
4938 enum built_in_function base;
4939 tree decl, args, itype;
4940 enum insn_code *optab;
4941
4942 /* Check for one of the supported fetch-op operations. */
4943 switch (TREE_CODE (rhs))
4944 {
4945 case PLUS_EXPR:
4946 base = BUILT_IN_FETCH_AND_ADD_N;
4947 optab = sync_add_optab;
4948 break;
4949 case MINUS_EXPR:
4950 base = BUILT_IN_FETCH_AND_SUB_N;
4951 optab = sync_add_optab;
4952 break;
4953 case BIT_AND_EXPR:
4954 base = BUILT_IN_FETCH_AND_AND_N;
4955 optab = sync_and_optab;
4956 break;
4957 case BIT_IOR_EXPR:
4958 base = BUILT_IN_FETCH_AND_OR_N;
4959 optab = sync_ior_optab;
4960 break;
4961 case BIT_XOR_EXPR:
4962 base = BUILT_IN_FETCH_AND_XOR_N;
4963 optab = sync_xor_optab;
4964 break;
4965 default:
4966 return GS_UNHANDLED;
4967 }
4968
4969 /* Make sure the expression is of the proper form. */
4970 if (goa_lhs_expr_p (TREE_OPERAND (rhs, 0), addr))
4971 rhs = TREE_OPERAND (rhs, 1);
4972 else if (commutative_tree_code (TREE_CODE (rhs))
4973 && goa_lhs_expr_p (TREE_OPERAND (rhs, 1), addr))
4974 rhs = TREE_OPERAND (rhs, 0);
4975 else
4976 return GS_UNHANDLED;
4977
4978 decl = built_in_decls[base + index + 1];
4979 itype = TREE_TYPE (TREE_TYPE (decl));
4980
4981 if (optab[TYPE_MODE (itype)] == CODE_FOR_nothing)
4982 return GS_UNHANDLED;
4983
4984 args = tree_cons (NULL, fold_convert (itype, rhs), NULL);
4985 args = tree_cons (NULL, addr, args);
4986 *expr_p = build_function_call_expr (decl, args);
4987 return GS_OK;
4988 }
4989
4990 /* A subroutine of gimplify_omp_atomic_pipeline. Walk *EXPR_P and replace
4991 appearances of *LHS_ADDR with LHS_VAR. If an expression does not involve
4992 the lhs, evaluate it into a temporary. Return 1 if the lhs appeared as
4993 a subexpression, 0 if it did not, or -1 if an error was encountered. */
4994
4995 static int
4996 goa_stabilize_expr (tree *expr_p, tree *pre_p, tree lhs_addr, tree lhs_var)
4997 {
4998 tree expr = *expr_p;
4999 int saw_lhs;
5000
5001 if (goa_lhs_expr_p (expr, lhs_addr))
5002 {
5003 *expr_p = lhs_var;
5004 return 1;
5005 }
5006 if (is_gimple_val (expr))
5007 return 0;
5008
5009 saw_lhs = 0;
5010 switch (TREE_CODE_CLASS (TREE_CODE (expr)))
5011 {
5012 case tcc_binary:
5013 saw_lhs |= goa_stabilize_expr (&TREE_OPERAND (expr, 1), pre_p,
5014 lhs_addr, lhs_var);
5015 case tcc_unary:
5016 saw_lhs |= goa_stabilize_expr (&TREE_OPERAND (expr, 0), pre_p,
5017 lhs_addr, lhs_var);
5018 break;
5019 default:
5020 break;
5021 }
5022
5023 if (saw_lhs == 0)
5024 {
5025 enum gimplify_status gs;
5026 gs = gimplify_expr (expr_p, pre_p, NULL, is_gimple_val, fb_rvalue);
5027 if (gs != GS_ALL_DONE)
5028 saw_lhs = -1;
5029 }
5030
5031 return saw_lhs;
5032 }
5033
5034 /* A subroutine of gimplify_omp_atomic. Implement the atomic operation as:
5035
5036 oldval = *addr;
5037 repeat:
5038 newval = rhs; // with oldval replacing *addr in rhs
5039 oldval = __sync_val_compare_and_swap (addr, oldval, newval);
5040 if (oldval != newval)
5041 goto repeat;
5042
5043 INDEX is log2 of the size of the data type, and thus usable to find the
5044 index of the builtin decl. */
5045
5046 static enum gimplify_status
5047 gimplify_omp_atomic_pipeline (tree *expr_p, tree *pre_p, tree addr,
5048 tree rhs, int index)
5049 {
5050 tree oldval, oldival, oldival2, newval, newival, label;
5051 tree type, itype, cmpxchg, args, x, iaddr;
5052
5053 cmpxchg = built_in_decls[BUILT_IN_VAL_COMPARE_AND_SWAP_N + index + 1];
5054 type = TYPE_MAIN_VARIANT (TREE_TYPE (TREE_TYPE (addr)));
5055 itype = TREE_TYPE (TREE_TYPE (cmpxchg));
5056
5057 if (sync_compare_and_swap[TYPE_MODE (itype)] == CODE_FOR_nothing)
5058 return GS_UNHANDLED;
5059
5060 oldval = create_tmp_var (type, NULL);
5061 newval = create_tmp_var (type, NULL);
5062
5063 /* Precompute as much of RHS as possible. In the same walk, replace
5064 occurrences of the lhs value with our temporary. */
5065 if (goa_stabilize_expr (&rhs, pre_p, addr, oldval) < 0)
5066 return GS_ERROR;
5067
5068 x = build_fold_indirect_ref (addr);
5069 x = build2 (MODIFY_EXPR, void_type_node, oldval, x);
5070 gimplify_and_add (x, pre_p);
5071
5072 /* For floating-point values, we'll need to view-convert them to integers
5073 so that we can perform the atomic compare and swap. Simplify the
5074 following code by always setting up the "i"ntegral variables. */
5075 if (INTEGRAL_TYPE_P (type) || POINTER_TYPE_P (type))
5076 {
5077 oldival = oldval;
5078 newival = newval;
5079 iaddr = addr;
5080 }
5081 else
5082 {
5083 oldival = create_tmp_var (itype, NULL);
5084 newival = create_tmp_var (itype, NULL);
5085
5086 x = build1 (VIEW_CONVERT_EXPR, itype, oldval);
5087 x = build2 (MODIFY_EXPR, void_type_node, oldival, x);
5088 gimplify_and_add (x, pre_p);
5089 iaddr = fold_convert (build_pointer_type (itype), addr);
5090 }
5091
5092 oldival2 = create_tmp_var (itype, NULL);
5093
5094 label = create_artificial_label ();
5095 x = build1 (LABEL_EXPR, void_type_node, label);
5096 gimplify_and_add (x, pre_p);
5097
5098 x = build2 (MODIFY_EXPR, void_type_node, newval, rhs);
5099 gimplify_and_add (x, pre_p);
5100
5101 if (newval != newival)
5102 {
5103 x = build1 (VIEW_CONVERT_EXPR, itype, newval);
5104 x = build2 (MODIFY_EXPR, void_type_node, newival, x);
5105 gimplify_and_add (x, pre_p);
5106 }
5107
5108 x = build2 (MODIFY_EXPR, void_type_node, oldival2, oldival);
5109 gimplify_and_add (x, pre_p);
5110
5111 args = tree_cons (NULL, fold_convert (itype, newival), NULL);
5112 args = tree_cons (NULL, fold_convert (itype, oldival), args);
5113 args = tree_cons (NULL, iaddr, args);
5114 x = build_function_call_expr (cmpxchg, args);
5115 if (oldval == oldival)
5116 x = fold_convert (type, x);
5117 x = build2 (MODIFY_EXPR, void_type_node, oldival, x);
5118 gimplify_and_add (x, pre_p);
5119
5120 /* For floating point, be prepared for the loop backedge. */
5121 if (oldval != oldival)
5122 {
5123 x = build1 (VIEW_CONVERT_EXPR, type, oldival);
5124 x = build2 (MODIFY_EXPR, void_type_node, oldval, x);
5125 gimplify_and_add (x, pre_p);
5126 }
5127
5128 /* Note that we always perform the comparison as an integer, even for
5129 floating point. This allows the atomic operation to properly
5130 succeed even with NaNs and -0.0. */
5131 x = build3 (COND_EXPR, void_type_node,
5132 build2 (NE_EXPR, boolean_type_node, oldival, oldival2),
5133 build1 (GOTO_EXPR, void_type_node, label), NULL);
5134 gimplify_and_add (x, pre_p);
5135
5136 *expr_p = NULL;
5137 return GS_ALL_DONE;
5138 }
5139
5140 /* A subroutine of gimplify_omp_atomic. Implement the atomic operation as:
5141
5142 GOMP_atomic_start ();
5143 *addr = rhs;
5144 GOMP_atomic_end ();
5145
5146 The result is not globally atomic, but works so long as all parallel
5147 references are within #pragma omp atomic directives. According to
5148 responses received from omp@openmp.org, appears to be within spec.
5149 Which makes sense, since that's how several other compilers handle
5150 this situation as well. */
5151
5152 static enum gimplify_status
5153 gimplify_omp_atomic_mutex (tree *expr_p, tree *pre_p, tree addr, tree rhs)
5154 {
5155 tree t;
5156
5157 t = built_in_decls[BUILT_IN_GOMP_ATOMIC_START];
5158 t = build_function_call_expr (t, NULL);
5159 gimplify_and_add (t, pre_p);
5160
5161 t = build_fold_indirect_ref (addr);
5162 t = build2 (MODIFY_EXPR, void_type_node, t, rhs);
5163 gimplify_and_add (t, pre_p);
5164
5165 t = built_in_decls[BUILT_IN_GOMP_ATOMIC_END];
5166 t = build_function_call_expr (t, NULL);
5167 gimplify_and_add (t, pre_p);
5168
5169 *expr_p = NULL;
5170 return GS_ALL_DONE;
5171 }
5172
5173 /* Gimplify an OMP_ATOMIC statement. */
5174
5175 static enum gimplify_status
5176 gimplify_omp_atomic (tree *expr_p, tree *pre_p)
5177 {
5178 tree addr = TREE_OPERAND (*expr_p, 0);
5179 tree rhs = TREE_OPERAND (*expr_p, 1);
5180 tree type = TYPE_MAIN_VARIANT (TREE_TYPE (TREE_TYPE (addr)));
5181 HOST_WIDE_INT index;
5182
5183 /* Make sure the type is one of the supported sizes. */
5184 index = tree_low_cst (TYPE_SIZE_UNIT (type), 1);
5185 index = exact_log2 (index);
5186 if (index >= 0 && index <= 4)
5187 {
5188 enum gimplify_status gs;
5189 unsigned int align;
5190
5191 if (DECL_P (TREE_OPERAND (addr, 0)))
5192 align = DECL_ALIGN_UNIT (TREE_OPERAND (addr, 0));
5193 else if (TREE_CODE (TREE_OPERAND (addr, 0)) == COMPONENT_REF
5194 && TREE_CODE (TREE_OPERAND (TREE_OPERAND (addr, 0), 1))
5195 == FIELD_DECL)
5196 align = DECL_ALIGN_UNIT (TREE_OPERAND (TREE_OPERAND (addr, 0), 1));
5197 else
5198 align = TYPE_ALIGN_UNIT (type);
5199
5200 /* __sync builtins require strict data alignment. */
5201 if (exact_log2 (align) >= index)
5202 {
5203 /* When possible, use specialized atomic update functions. */
5204 if (INTEGRAL_TYPE_P (type) || POINTER_TYPE_P (type))
5205 {
5206 gs = gimplify_omp_atomic_fetch_op (expr_p, addr, rhs, index);
5207 if (gs != GS_UNHANDLED)
5208 return gs;
5209 }
5210
5211 /* If we don't have specialized __sync builtins, try and implement
5212 as a compare and swap loop. */
5213 gs = gimplify_omp_atomic_pipeline (expr_p, pre_p, addr, rhs, index);
5214 if (gs != GS_UNHANDLED)
5215 return gs;
5216 }
5217 }
5218
5219 /* The ultimate fallback is wrapping the operation in a mutex. */
5220 return gimplify_omp_atomic_mutex (expr_p, pre_p, addr, rhs);
5221 }
5222
5223 /* Gimplifies the expression tree pointed to by EXPR_P. Return 0 if
5224 gimplification failed.
5225
5226 PRE_P points to the list where side effects that must happen before
5227 EXPR should be stored.
5228
5229 POST_P points to the list where side effects that must happen after
5230 EXPR should be stored, or NULL if there is no suitable list. In
5231 that case, we copy the result to a temporary, emit the
5232 post-effects, and then return the temporary.
5233
5234 GIMPLE_TEST_F points to a function that takes a tree T and
5235 returns nonzero if T is in the GIMPLE form requested by the
5236 caller. The GIMPLE predicates are in tree-gimple.c.
5237
5238 This test is used twice. Before gimplification, the test is
5239 invoked to determine whether *EXPR_P is already gimple enough. If
5240 that fails, *EXPR_P is gimplified according to its code and
5241 GIMPLE_TEST_F is called again. If the test still fails, then a new
5242 temporary variable is created and assigned the value of the
5243 gimplified expression.
5244
5245 FALLBACK tells the function what sort of a temporary we want. If the 1
5246 bit is set, an rvalue is OK. If the 2 bit is set, an lvalue is OK.
5247 If both are set, either is OK, but an lvalue is preferable.
5248
5249 The return value is either GS_ERROR or GS_ALL_DONE, since this function
5250 iterates until solution. */
5251
5252 enum gimplify_status
5253 gimplify_expr (tree *expr_p, tree *pre_p, tree *post_p,
5254 bool (* gimple_test_f) (tree), fallback_t fallback)
5255 {
5256 tree tmp;
5257 tree internal_pre = NULL_TREE;
5258 tree internal_post = NULL_TREE;
5259 tree save_expr;
5260 int is_statement = (pre_p == NULL);
5261 location_t saved_location;
5262 enum gimplify_status ret;
5263
5264 save_expr = *expr_p;
5265 if (save_expr == NULL_TREE)
5266 return GS_ALL_DONE;
5267
5268 /* We used to check the predicate here and return immediately if it
5269 succeeds. This is wrong; the design is for gimplification to be
5270 idempotent, and for the predicates to only test for valid forms, not
5271 whether they are fully simplified. */
5272
5273 /* Set up our internal queues if needed. */
5274 if (pre_p == NULL)
5275 pre_p = &internal_pre;
5276 if (post_p == NULL)
5277 post_p = &internal_post;
5278
5279 saved_location = input_location;
5280 if (save_expr != error_mark_node
5281 && EXPR_HAS_LOCATION (*expr_p))
5282 input_location = EXPR_LOCATION (*expr_p);
5283
5284 /* Loop over the specific gimplifiers until the toplevel node
5285 remains the same. */
5286 do
5287 {
5288 /* Strip away as many useless type conversions as possible
5289 at the toplevel. */
5290 STRIP_USELESS_TYPE_CONVERSION (*expr_p);
5291
5292 /* Remember the expr. */
5293 save_expr = *expr_p;
5294
5295 /* Die, die, die, my darling. */
5296 if (save_expr == error_mark_node
5297 || (TREE_TYPE (save_expr)
5298 && TREE_TYPE (save_expr) == error_mark_node))
5299 {
5300 ret = GS_ERROR;
5301 break;
5302 }
5303
5304 /* Do any language-specific gimplification. */
5305 ret = lang_hooks.gimplify_expr (expr_p, pre_p, post_p);
5306 if (ret == GS_OK)
5307 {
5308 if (*expr_p == NULL_TREE)
5309 break;
5310 if (*expr_p != save_expr)
5311 continue;
5312 }
5313 else if (ret != GS_UNHANDLED)
5314 break;
5315
5316 ret = GS_OK;
5317 switch (TREE_CODE (*expr_p))
5318 {
5319 /* First deal with the special cases. */
5320
5321 case POSTINCREMENT_EXPR:
5322 case POSTDECREMENT_EXPR:
5323 case PREINCREMENT_EXPR:
5324 case PREDECREMENT_EXPR:
5325 ret = gimplify_self_mod_expr (expr_p, pre_p, post_p,
5326 fallback != fb_none);
5327 break;
5328
5329 case ARRAY_REF:
5330 case ARRAY_RANGE_REF:
5331 case REALPART_EXPR:
5332 case IMAGPART_EXPR:
5333 case COMPONENT_REF:
5334 case VIEW_CONVERT_EXPR:
5335 ret = gimplify_compound_lval (expr_p, pre_p, post_p,
5336 fallback ? fallback : fb_rvalue);
5337 break;
5338
5339 case COND_EXPR:
5340 ret = gimplify_cond_expr (expr_p, pre_p, fallback);
5341 /* C99 code may assign to an array in a structure value of a
5342 conditional expression, and this has undefined behavior
5343 only on execution, so create a temporary if an lvalue is
5344 required. */
5345 if (fallback == fb_lvalue)
5346 {
5347 *expr_p = get_initialized_tmp_var (*expr_p, pre_p, post_p);
5348 lang_hooks.mark_addressable (*expr_p);
5349 }
5350 break;
5351
5352 case CALL_EXPR:
5353 ret = gimplify_call_expr (expr_p, pre_p, fallback != fb_none);
5354 /* C99 code may assign to an array in a structure returned
5355 from a function, and this has undefined behavior only on
5356 execution, so create a temporary if an lvalue is
5357 required. */
5358 if (fallback == fb_lvalue)
5359 {
5360 *expr_p = get_initialized_tmp_var (*expr_p, pre_p, post_p);
5361 lang_hooks.mark_addressable (*expr_p);
5362 }
5363 break;
5364
5365 case TREE_LIST:
5366 gcc_unreachable ();
5367
5368 case COMPOUND_EXPR:
5369 ret = gimplify_compound_expr (expr_p, pre_p, fallback != fb_none);
5370 break;
5371
5372 case MODIFY_EXPR:
5373 case INIT_EXPR:
5374 ret = gimplify_modify_expr (expr_p, pre_p, post_p,
5375 fallback != fb_none);
5376
5377 /* The distinction between MODIFY_EXPR and INIT_EXPR is no longer
5378 useful. */
5379 if (*expr_p && TREE_CODE (*expr_p) == INIT_EXPR)
5380 TREE_SET_CODE (*expr_p, MODIFY_EXPR);
5381 break;
5382
5383 case TRUTH_ANDIF_EXPR:
5384 case TRUTH_ORIF_EXPR:
5385 ret = gimplify_boolean_expr (expr_p);
5386 break;
5387
5388 case TRUTH_NOT_EXPR:
5389 TREE_OPERAND (*expr_p, 0)
5390 = gimple_boolify (TREE_OPERAND (*expr_p, 0));
5391 ret = gimplify_expr (&TREE_OPERAND (*expr_p, 0), pre_p, post_p,
5392 is_gimple_val, fb_rvalue);
5393 recalculate_side_effects (*expr_p);
5394 break;
5395
5396 case ADDR_EXPR:
5397 ret = gimplify_addr_expr (expr_p, pre_p, post_p);
5398 break;
5399
5400 case VA_ARG_EXPR:
5401 ret = gimplify_va_arg_expr (expr_p, pre_p, post_p);
5402 break;
5403
5404 case CONVERT_EXPR:
5405 case NOP_EXPR:
5406 if (IS_EMPTY_STMT (*expr_p))
5407 {
5408 ret = GS_ALL_DONE;
5409 break;
5410 }
5411
5412 if (VOID_TYPE_P (TREE_TYPE (*expr_p))
5413 || fallback == fb_none)
5414 {
5415 /* Just strip a conversion to void (or in void context) and
5416 try again. */
5417 *expr_p = TREE_OPERAND (*expr_p, 0);
5418 break;
5419 }
5420
5421 ret = gimplify_conversion (expr_p);
5422 if (ret == GS_ERROR)
5423 break;
5424 if (*expr_p != save_expr)
5425 break;
5426 /* FALLTHRU */
5427
5428 case FIX_TRUNC_EXPR:
5429 case FIX_CEIL_EXPR:
5430 case FIX_FLOOR_EXPR:
5431 case FIX_ROUND_EXPR:
5432 /* unary_expr: ... | '(' cast ')' val | ... */
5433 ret = gimplify_expr (&TREE_OPERAND (*expr_p, 0), pre_p, post_p,
5434 is_gimple_val, fb_rvalue);
5435 recalculate_side_effects (*expr_p);
5436 break;
5437
5438 case INDIRECT_REF:
5439 *expr_p = fold_indirect_ref (*expr_p);
5440 if (*expr_p != save_expr)
5441 break;
5442 /* else fall through. */
5443 case ALIGN_INDIRECT_REF:
5444 case MISALIGNED_INDIRECT_REF:
5445 ret = gimplify_expr (&TREE_OPERAND (*expr_p, 0), pre_p, post_p,
5446 is_gimple_reg, fb_rvalue);
5447 recalculate_side_effects (*expr_p);
5448 break;
5449
5450 /* Constants need not be gimplified. */
5451 case INTEGER_CST:
5452 case REAL_CST:
5453 case STRING_CST:
5454 case COMPLEX_CST:
5455 case VECTOR_CST:
5456 ret = GS_ALL_DONE;
5457 break;
5458
5459 case CONST_DECL:
5460 /* If we require an lvalue, such as for ADDR_EXPR, retain the
5461 CONST_DECL node. Otherwise the decl is replaceable by its
5462 value. */
5463 /* ??? Should be == fb_lvalue, but ADDR_EXPR passes fb_either. */
5464 if (fallback & fb_lvalue)
5465 ret = GS_ALL_DONE;
5466 else
5467 *expr_p = DECL_INITIAL (*expr_p);
5468 break;
5469
5470 case DECL_EXPR:
5471 ret = gimplify_decl_expr (expr_p);
5472 break;
5473
5474 case EXC_PTR_EXPR:
5475 /* FIXME make this a decl. */
5476 ret = GS_ALL_DONE;
5477 break;
5478
5479 case BIND_EXPR:
5480 ret = gimplify_bind_expr (expr_p, NULL, pre_p);
5481 break;
5482
5483 case LOOP_EXPR:
5484 ret = gimplify_loop_expr (expr_p, pre_p);
5485 break;
5486
5487 case SWITCH_EXPR:
5488 ret = gimplify_switch_expr (expr_p, pre_p);
5489 break;
5490
5491 case EXIT_EXPR:
5492 ret = gimplify_exit_expr (expr_p);
5493 break;
5494
5495 case GOTO_EXPR:
5496 /* If the target is not LABEL, then it is a computed jump
5497 and the target needs to be gimplified. */
5498 if (TREE_CODE (GOTO_DESTINATION (*expr_p)) != LABEL_DECL)
5499 ret = gimplify_expr (&GOTO_DESTINATION (*expr_p), pre_p,
5500 NULL, is_gimple_val, fb_rvalue);
5501 break;
5502
5503 case LABEL_EXPR:
5504 ret = GS_ALL_DONE;
5505 gcc_assert (decl_function_context (LABEL_EXPR_LABEL (*expr_p))
5506 == current_function_decl);
5507 break;
5508
5509 case CASE_LABEL_EXPR:
5510 ret = gimplify_case_label_expr (expr_p);
5511 break;
5512
5513 case RETURN_EXPR:
5514 ret = gimplify_return_expr (*expr_p, pre_p);
5515 break;
5516
5517 case CONSTRUCTOR:
5518 /* Don't reduce this in place; let gimplify_init_constructor work its
5519 magic. Buf if we're just elaborating this for side effects, just
5520 gimplify any element that has side-effects. */
5521 if (fallback == fb_none)
5522 {
5523 unsigned HOST_WIDE_INT ix;
5524 constructor_elt *ce;
5525 tree temp = NULL_TREE;
5526 for (ix = 0;
5527 VEC_iterate (constructor_elt, CONSTRUCTOR_ELTS (*expr_p),
5528 ix, ce);
5529 ix++)
5530 if (TREE_SIDE_EFFECTS (ce->value))
5531 append_to_statement_list (ce->value, &temp);
5532
5533 *expr_p = temp;
5534 ret = GS_OK;
5535 }
5536 /* C99 code may assign to an array in a constructed
5537 structure or union, and this has undefined behavior only
5538 on execution, so create a temporary if an lvalue is
5539 required. */
5540 else if (fallback == fb_lvalue)
5541 {
5542 *expr_p = get_initialized_tmp_var (*expr_p, pre_p, post_p);
5543 lang_hooks.mark_addressable (*expr_p);
5544 }
5545 else
5546 ret = GS_ALL_DONE;
5547 break;
5548
5549 /* The following are special cases that are not handled by the
5550 original GIMPLE grammar. */
5551
5552 /* SAVE_EXPR nodes are converted into a GIMPLE identifier and
5553 eliminated. */
5554 case SAVE_EXPR:
5555 ret = gimplify_save_expr (expr_p, pre_p, post_p);
5556 break;
5557
5558 case BIT_FIELD_REF:
5559 {
5560 enum gimplify_status r0, r1, r2;
5561
5562 r0 = gimplify_expr (&TREE_OPERAND (*expr_p, 0), pre_p, post_p,
5563 is_gimple_lvalue, fb_either);
5564 r1 = gimplify_expr (&TREE_OPERAND (*expr_p, 1), pre_p, post_p,
5565 is_gimple_val, fb_rvalue);
5566 r2 = gimplify_expr (&TREE_OPERAND (*expr_p, 2), pre_p, post_p,
5567 is_gimple_val, fb_rvalue);
5568 recalculate_side_effects (*expr_p);
5569
5570 ret = MIN (r0, MIN (r1, r2));
5571 }
5572 break;
5573
5574 case NON_LVALUE_EXPR:
5575 /* This should have been stripped above. */
5576 gcc_unreachable ();
5577
5578 case ASM_EXPR:
5579 ret = gimplify_asm_expr (expr_p, pre_p, post_p);
5580 break;
5581
5582 case TRY_FINALLY_EXPR:
5583 case TRY_CATCH_EXPR:
5584 gimplify_to_stmt_list (&TREE_OPERAND (*expr_p, 0));
5585 gimplify_to_stmt_list (&TREE_OPERAND (*expr_p, 1));
5586 ret = GS_ALL_DONE;
5587 break;
5588
5589 case CLEANUP_POINT_EXPR:
5590 ret = gimplify_cleanup_point_expr (expr_p, pre_p);
5591 break;
5592
5593 case TARGET_EXPR:
5594 ret = gimplify_target_expr (expr_p, pre_p, post_p);
5595 break;
5596
5597 case CATCH_EXPR:
5598 gimplify_to_stmt_list (&CATCH_BODY (*expr_p));
5599 ret = GS_ALL_DONE;
5600 break;
5601
5602 case EH_FILTER_EXPR:
5603 gimplify_to_stmt_list (&EH_FILTER_FAILURE (*expr_p));
5604 ret = GS_ALL_DONE;
5605 break;
5606
5607 case OBJ_TYPE_REF:
5608 {
5609 enum gimplify_status r0, r1;
5610 r0 = gimplify_expr (&OBJ_TYPE_REF_OBJECT (*expr_p), pre_p, post_p,
5611 is_gimple_val, fb_rvalue);
5612 r1 = gimplify_expr (&OBJ_TYPE_REF_EXPR (*expr_p), pre_p, post_p,
5613 is_gimple_val, fb_rvalue);
5614 ret = MIN (r0, r1);
5615 }
5616 break;
5617
5618 case LABEL_DECL:
5619 /* We get here when taking the address of a label. We mark
5620 the label as "forced"; meaning it can never be removed and
5621 it is a potential target for any computed goto. */
5622 FORCED_LABEL (*expr_p) = 1;
5623 ret = GS_ALL_DONE;
5624 break;
5625
5626 case STATEMENT_LIST:
5627 ret = gimplify_statement_list (expr_p);
5628 break;
5629
5630 case WITH_SIZE_EXPR:
5631 {
5632 gimplify_expr (&TREE_OPERAND (*expr_p, 0), pre_p,
5633 post_p == &internal_post ? NULL : post_p,
5634 gimple_test_f, fallback);
5635 gimplify_expr (&TREE_OPERAND (*expr_p, 1), pre_p, post_p,
5636 is_gimple_val, fb_rvalue);
5637 }
5638 break;
5639
5640 case VAR_DECL:
5641 case PARM_DECL:
5642 ret = gimplify_var_or_parm_decl (expr_p);
5643 break;
5644
5645 case RESULT_DECL:
5646 /* When within an OpenMP context, notice uses of variables. */
5647 if (gimplify_omp_ctxp)
5648 omp_notice_variable (gimplify_omp_ctxp, *expr_p, true);
5649 ret = GS_ALL_DONE;
5650 break;
5651
5652 case SSA_NAME:
5653 /* Allow callbacks into the gimplifier during optimization. */
5654 ret = GS_ALL_DONE;
5655 break;
5656
5657 case OMP_PARALLEL:
5658 ret = gimplify_omp_parallel (expr_p, pre_p);
5659 break;
5660
5661 case OMP_FOR:
5662 ret = gimplify_omp_for (expr_p, pre_p);
5663 break;
5664
5665 case OMP_SECTIONS:
5666 case OMP_SINGLE:
5667 ret = gimplify_omp_workshare (expr_p, pre_p);
5668 break;
5669
5670 case OMP_SECTION:
5671 case OMP_MASTER:
5672 case OMP_ORDERED:
5673 case OMP_CRITICAL:
5674 gimplify_to_stmt_list (&OMP_BODY (*expr_p));
5675 break;
5676
5677 case OMP_ATOMIC:
5678 ret = gimplify_omp_atomic (expr_p, pre_p);
5679 break;
5680
5681 case OMP_RETURN:
5682 case OMP_CONTINUE:
5683 ret = GS_ALL_DONE;
5684 break;
5685
5686 default:
5687 switch (TREE_CODE_CLASS (TREE_CODE (*expr_p)))
5688 {
5689 case tcc_comparison:
5690 /* If this is a comparison of objects of aggregate type,
5691 handle it specially (by converting to a call to
5692 memcmp). It would be nice to only have to do this
5693 for variable-sized objects, but then we'd have to
5694 allow the same nest of reference nodes we allow for
5695 MODIFY_EXPR and that's too complex. */
5696 if (!AGGREGATE_TYPE_P (TREE_TYPE (TREE_OPERAND (*expr_p, 1))))
5697 goto expr_2;
5698 ret = gimplify_variable_sized_compare (expr_p);
5699 break;
5700
5701 /* If *EXPR_P does not need to be special-cased, handle it
5702 according to its class. */
5703 case tcc_unary:
5704 ret = gimplify_expr (&TREE_OPERAND (*expr_p, 0), pre_p,
5705 post_p, is_gimple_val, fb_rvalue);
5706 break;
5707
5708 case tcc_binary:
5709 expr_2:
5710 {
5711 enum gimplify_status r0, r1;
5712
5713 r0 = gimplify_expr (&TREE_OPERAND (*expr_p, 0), pre_p,
5714 post_p, is_gimple_val, fb_rvalue);
5715 r1 = gimplify_expr (&TREE_OPERAND (*expr_p, 1), pre_p,
5716 post_p, is_gimple_val, fb_rvalue);
5717
5718 ret = MIN (r0, r1);
5719 break;
5720 }
5721
5722 case tcc_declaration:
5723 case tcc_constant:
5724 ret = GS_ALL_DONE;
5725 goto dont_recalculate;
5726
5727 default:
5728 gcc_assert (TREE_CODE (*expr_p) == TRUTH_AND_EXPR
5729 || TREE_CODE (*expr_p) == TRUTH_OR_EXPR
5730 || TREE_CODE (*expr_p) == TRUTH_XOR_EXPR);
5731 goto expr_2;
5732 }
5733
5734 recalculate_side_effects (*expr_p);
5735 dont_recalculate:
5736 break;
5737 }
5738
5739 /* If we replaced *expr_p, gimplify again. */
5740 if (ret == GS_OK && (*expr_p == NULL || *expr_p == save_expr))
5741 ret = GS_ALL_DONE;
5742 }
5743 while (ret == GS_OK);
5744
5745 /* If we encountered an error_mark somewhere nested inside, either
5746 stub out the statement or propagate the error back out. */
5747 if (ret == GS_ERROR)
5748 {
5749 if (is_statement)
5750 *expr_p = NULL;
5751 goto out;
5752 }
5753
5754 /* This was only valid as a return value from the langhook, which
5755 we handled. Make sure it doesn't escape from any other context. */
5756 gcc_assert (ret != GS_UNHANDLED);
5757
5758 if (fallback == fb_none && *expr_p && !is_gimple_stmt (*expr_p))
5759 {
5760 /* We aren't looking for a value, and we don't have a valid
5761 statement. If it doesn't have side-effects, throw it away. */
5762 if (!TREE_SIDE_EFFECTS (*expr_p))
5763 *expr_p = NULL;
5764 else if (!TREE_THIS_VOLATILE (*expr_p))
5765 {
5766 /* This is probably a _REF that contains something nested that
5767 has side effects. Recurse through the operands to find it. */
5768 enum tree_code code = TREE_CODE (*expr_p);
5769
5770 switch (code)
5771 {
5772 case COMPONENT_REF:
5773 case REALPART_EXPR:
5774 case IMAGPART_EXPR:
5775 case VIEW_CONVERT_EXPR:
5776 gimplify_expr (&TREE_OPERAND (*expr_p, 0), pre_p, post_p,
5777 gimple_test_f, fallback);
5778 break;
5779
5780 case ARRAY_REF: case ARRAY_RANGE_REF:
5781 gimplify_expr (&TREE_OPERAND (*expr_p, 0), pre_p, post_p,
5782 gimple_test_f, fallback);
5783 gimplify_expr (&TREE_OPERAND (*expr_p, 1), pre_p, post_p,
5784 gimple_test_f, fallback);
5785 break;
5786
5787 default:
5788 /* Anything else with side-effects must be converted to
5789 a valid statement before we get here. */
5790 gcc_unreachable ();
5791 }
5792
5793 *expr_p = NULL;
5794 }
5795 else if (COMPLETE_TYPE_P (TREE_TYPE (*expr_p)))
5796 {
5797 /* Historically, the compiler has treated a bare
5798 reference to a volatile lvalue as forcing a load. */
5799 tree type = TYPE_MAIN_VARIANT (TREE_TYPE (*expr_p));
5800 /* Normally, we do not want to create a temporary for a
5801 TREE_ADDRESSABLE type because such a type should not be
5802 copied by bitwise-assignment. However, we make an
5803 exception here, as all we are doing here is ensuring that
5804 we read the bytes that make up the type. We use
5805 create_tmp_var_raw because create_tmp_var will abort when
5806 given a TREE_ADDRESSABLE type. */
5807 tree tmp = create_tmp_var_raw (type, "vol");
5808 gimple_add_tmp_var (tmp);
5809 *expr_p = build2 (MODIFY_EXPR, type, tmp, *expr_p);
5810 }
5811 else
5812 /* We can't do anything useful with a volatile reference to
5813 incomplete type, so just throw it away. */
5814 *expr_p = NULL;
5815 }
5816
5817 /* If we are gimplifying at the statement level, we're done. Tack
5818 everything together and replace the original statement with the
5819 gimplified form. */
5820 if (fallback == fb_none || is_statement)
5821 {
5822 if (internal_pre || internal_post)
5823 {
5824 append_to_statement_list (*expr_p, &internal_pre);
5825 append_to_statement_list (internal_post, &internal_pre);
5826 annotate_all_with_locus (&internal_pre, input_location);
5827 *expr_p = internal_pre;
5828 }
5829 else if (!*expr_p)
5830 ;
5831 else if (TREE_CODE (*expr_p) == STATEMENT_LIST)
5832 annotate_all_with_locus (expr_p, input_location);
5833 else
5834 annotate_one_with_locus (*expr_p, input_location);
5835 goto out;
5836 }
5837
5838 /* Otherwise we're gimplifying a subexpression, so the resulting value is
5839 interesting. */
5840
5841 /* If it's sufficiently simple already, we're done. Unless we are
5842 handling some post-effects internally; if that's the case, we need to
5843 copy into a temp before adding the post-effects to the tree. */
5844 if (!internal_post && (*gimple_test_f) (*expr_p))
5845 goto out;
5846
5847 /* Otherwise, we need to create a new temporary for the gimplified
5848 expression. */
5849
5850 /* We can't return an lvalue if we have an internal postqueue. The
5851 object the lvalue refers to would (probably) be modified by the
5852 postqueue; we need to copy the value out first, which means an
5853 rvalue. */
5854 if ((fallback & fb_lvalue) && !internal_post
5855 && is_gimple_addressable (*expr_p))
5856 {
5857 /* An lvalue will do. Take the address of the expression, store it
5858 in a temporary, and replace the expression with an INDIRECT_REF of
5859 that temporary. */
5860 tmp = build_fold_addr_expr (*expr_p);
5861 gimplify_expr (&tmp, pre_p, post_p, is_gimple_reg, fb_rvalue);
5862 *expr_p = build1 (INDIRECT_REF, TREE_TYPE (TREE_TYPE (tmp)), tmp);
5863 }
5864 else if ((fallback & fb_rvalue) && is_gimple_formal_tmp_rhs (*expr_p))
5865 {
5866 gcc_assert (!VOID_TYPE_P (TREE_TYPE (*expr_p)));
5867
5868 /* An rvalue will do. Assign the gimplified expression into a new
5869 temporary TMP and replace the original expression with TMP. */
5870
5871 if (internal_post || (fallback & fb_lvalue))
5872 /* The postqueue might change the value of the expression between
5873 the initialization and use of the temporary, so we can't use a
5874 formal temp. FIXME do we care? */
5875 *expr_p = get_initialized_tmp_var (*expr_p, pre_p, post_p);
5876 else
5877 *expr_p = get_formal_tmp_var (*expr_p, pre_p);
5878
5879 if (TREE_CODE (*expr_p) != SSA_NAME)
5880 DECL_GIMPLE_FORMAL_TEMP_P (*expr_p) = 1;
5881 }
5882 else
5883 {
5884 #ifdef ENABLE_CHECKING
5885 if (!(fallback & fb_mayfail))
5886 {
5887 fprintf (stderr, "gimplification failed:\n");
5888 print_generic_expr (stderr, *expr_p, 0);
5889 debug_tree (*expr_p);
5890 internal_error ("gimplification failed");
5891 }
5892 #endif
5893 gcc_assert (fallback & fb_mayfail);
5894 /* If this is an asm statement, and the user asked for the
5895 impossible, don't die. Fail and let gimplify_asm_expr
5896 issue an error. */
5897 ret = GS_ERROR;
5898 goto out;
5899 }
5900
5901 /* Make sure the temporary matches our predicate. */
5902 gcc_assert ((*gimple_test_f) (*expr_p));
5903
5904 if (internal_post)
5905 {
5906 annotate_all_with_locus (&internal_post, input_location);
5907 append_to_statement_list (internal_post, pre_p);
5908 }
5909
5910 out:
5911 input_location = saved_location;
5912 return ret;
5913 }
5914
5915 /* Look through TYPE for variable-sized objects and gimplify each such
5916 size that we find. Add to LIST_P any statements generated. */
5917
5918 void
5919 gimplify_type_sizes (tree type, tree *list_p)
5920 {
5921 tree field, t;
5922
5923 if (type == NULL || type == error_mark_node)
5924 return;
5925
5926 /* We first do the main variant, then copy into any other variants. */
5927 type = TYPE_MAIN_VARIANT (type);
5928
5929 /* Avoid infinite recursion. */
5930 if (TYPE_SIZES_GIMPLIFIED (type))
5931 return;
5932
5933 TYPE_SIZES_GIMPLIFIED (type) = 1;
5934
5935 switch (TREE_CODE (type))
5936 {
5937 case INTEGER_TYPE:
5938 case ENUMERAL_TYPE:
5939 case BOOLEAN_TYPE:
5940 case REAL_TYPE:
5941 gimplify_one_sizepos (&TYPE_MIN_VALUE (type), list_p);
5942 gimplify_one_sizepos (&TYPE_MAX_VALUE (type), list_p);
5943
5944 for (t = TYPE_NEXT_VARIANT (type); t; t = TYPE_NEXT_VARIANT (t))
5945 {
5946 TYPE_MIN_VALUE (t) = TYPE_MIN_VALUE (type);
5947 TYPE_MAX_VALUE (t) = TYPE_MAX_VALUE (type);
5948 }
5949 break;
5950
5951 case ARRAY_TYPE:
5952 /* These types may not have declarations, so handle them here. */
5953 gimplify_type_sizes (TREE_TYPE (type), list_p);
5954 gimplify_type_sizes (TYPE_DOMAIN (type), list_p);
5955 break;
5956
5957 case RECORD_TYPE:
5958 case UNION_TYPE:
5959 case QUAL_UNION_TYPE:
5960 for (field = TYPE_FIELDS (type); field; field = TREE_CHAIN (field))
5961 if (TREE_CODE (field) == FIELD_DECL)
5962 {
5963 gimplify_one_sizepos (&DECL_FIELD_OFFSET (field), list_p);
5964 gimplify_type_sizes (TREE_TYPE (field), list_p);
5965 }
5966 break;
5967
5968 case POINTER_TYPE:
5969 case REFERENCE_TYPE:
5970 gimplify_type_sizes (TREE_TYPE (type), list_p);
5971 break;
5972
5973 default:
5974 break;
5975 }
5976
5977 gimplify_one_sizepos (&TYPE_SIZE (type), list_p);
5978 gimplify_one_sizepos (&TYPE_SIZE_UNIT (type), list_p);
5979
5980 for (t = TYPE_NEXT_VARIANT (type); t; t = TYPE_NEXT_VARIANT (t))
5981 {
5982 TYPE_SIZE (t) = TYPE_SIZE (type);
5983 TYPE_SIZE_UNIT (t) = TYPE_SIZE_UNIT (type);
5984 TYPE_SIZES_GIMPLIFIED (t) = 1;
5985 }
5986 }
5987
5988 /* A subroutine of gimplify_type_sizes to make sure that *EXPR_P,
5989 a size or position, has had all of its SAVE_EXPRs evaluated.
5990 We add any required statements to STMT_P. */
5991
5992 void
5993 gimplify_one_sizepos (tree *expr_p, tree *stmt_p)
5994 {
5995 tree type, expr = *expr_p;
5996
5997 /* We don't do anything if the value isn't there, is constant, or contains
5998 A PLACEHOLDER_EXPR. We also don't want to do anything if it's already
5999 a VAR_DECL. If it's a VAR_DECL from another function, the gimplifier
6000 will want to replace it with a new variable, but that will cause problems
6001 if this type is from outside the function. It's OK to have that here. */
6002 if (expr == NULL_TREE || TREE_CONSTANT (expr)
6003 || TREE_CODE (expr) == VAR_DECL
6004 || CONTAINS_PLACEHOLDER_P (expr))
6005 return;
6006
6007 type = TREE_TYPE (expr);
6008 *expr_p = unshare_expr (expr);
6009
6010 gimplify_expr (expr_p, stmt_p, NULL, is_gimple_val, fb_rvalue);
6011 expr = *expr_p;
6012
6013 /* Verify that we've an exact type match with the original expression.
6014 In particular, we do not wish to drop a "sizetype" in favour of a
6015 type of similar dimensions. We don't want to pollute the generic
6016 type-stripping code with this knowledge because it doesn't matter
6017 for the bulk of GENERIC/GIMPLE. It only matters that TYPE_SIZE_UNIT
6018 and friends retain their "sizetype-ness". */
6019 if (TREE_TYPE (expr) != type
6020 && TREE_CODE (type) == INTEGER_TYPE
6021 && TYPE_IS_SIZETYPE (type))
6022 {
6023 tree tmp;
6024
6025 *expr_p = create_tmp_var (type, NULL);
6026 tmp = build1 (NOP_EXPR, type, expr);
6027 tmp = build2 (MODIFY_EXPR, type, *expr_p, tmp);
6028 if (EXPR_HAS_LOCATION (expr))
6029 SET_EXPR_LOCUS (tmp, EXPR_LOCUS (expr));
6030 else
6031 SET_EXPR_LOCATION (tmp, input_location);
6032
6033 gimplify_and_add (tmp, stmt_p);
6034 }
6035 }
6036 \f
6037 #ifdef ENABLE_CHECKING
6038 /* Compare types A and B for a "close enough" match. */
6039
6040 static bool
6041 cpt_same_type (tree a, tree b)
6042 {
6043 if (lang_hooks.types_compatible_p (a, b))
6044 return true;
6045
6046 /* ??? The C++ FE decomposes METHOD_TYPES to FUNCTION_TYPES and doesn't
6047 link them together. This routine is intended to catch type errors
6048 that will affect the optimizers, and the optimizers don't add new
6049 dereferences of function pointers, so ignore it. */
6050 if ((TREE_CODE (a) == FUNCTION_TYPE || TREE_CODE (a) == METHOD_TYPE)
6051 && (TREE_CODE (b) == FUNCTION_TYPE || TREE_CODE (b) == METHOD_TYPE))
6052 return true;
6053
6054 /* ??? The C FE pushes type qualifiers after the fact into the type of
6055 the element from the type of the array. See build_unary_op's handling
6056 of ADDR_EXPR. This seems wrong -- if we were going to do this, we
6057 should have done it when creating the variable in the first place.
6058 Alternately, why aren't the two array types made variants? */
6059 if (TREE_CODE (a) == ARRAY_TYPE && TREE_CODE (b) == ARRAY_TYPE)
6060 return cpt_same_type (TREE_TYPE (a), TREE_TYPE (b));
6061
6062 /* And because of those, we have to recurse down through pointers. */
6063 if (POINTER_TYPE_P (a) && POINTER_TYPE_P (b))
6064 return cpt_same_type (TREE_TYPE (a), TREE_TYPE (b));
6065
6066 return false;
6067 }
6068
6069 /* Check for some cases of the front end missing cast expressions.
6070 The type of a dereference should correspond to the pointer type;
6071 similarly the type of an address should match its object. */
6072
6073 static tree
6074 check_pointer_types_r (tree *tp, int *walk_subtrees ATTRIBUTE_UNUSED,
6075 void *data ATTRIBUTE_UNUSED)
6076 {
6077 tree t = *tp;
6078 tree ptype, otype, dtype;
6079
6080 switch (TREE_CODE (t))
6081 {
6082 case INDIRECT_REF:
6083 case ARRAY_REF:
6084 otype = TREE_TYPE (t);
6085 ptype = TREE_TYPE (TREE_OPERAND (t, 0));
6086 dtype = TREE_TYPE (ptype);
6087 gcc_assert (cpt_same_type (otype, dtype));
6088 break;
6089
6090 case ADDR_EXPR:
6091 ptype = TREE_TYPE (t);
6092 otype = TREE_TYPE (TREE_OPERAND (t, 0));
6093 dtype = TREE_TYPE (ptype);
6094 if (!cpt_same_type (otype, dtype))
6095 {
6096 /* &array is allowed to produce a pointer to the element, rather than
6097 a pointer to the array type. We must allow this in order to
6098 properly represent assigning the address of an array in C into
6099 pointer to the element type. */
6100 gcc_assert (TREE_CODE (otype) == ARRAY_TYPE
6101 && POINTER_TYPE_P (ptype)
6102 && cpt_same_type (TREE_TYPE (otype), dtype));
6103 break;
6104 }
6105 break;
6106
6107 default:
6108 return NULL_TREE;
6109 }
6110
6111
6112 return NULL_TREE;
6113 }
6114 #endif
6115
6116 /* Gimplify the body of statements pointed to by BODY_P. FNDECL is the
6117 function decl containing BODY. */
6118
6119 void
6120 gimplify_body (tree *body_p, tree fndecl, bool do_parms)
6121 {
6122 location_t saved_location = input_location;
6123 tree body, parm_stmts;
6124
6125 timevar_push (TV_TREE_GIMPLIFY);
6126
6127 gcc_assert (gimplify_ctxp == NULL);
6128 push_gimplify_context ();
6129
6130 /* Unshare most shared trees in the body and in that of any nested functions.
6131 It would seem we don't have to do this for nested functions because
6132 they are supposed to be output and then the outer function gimplified
6133 first, but the g++ front end doesn't always do it that way. */
6134 unshare_body (body_p, fndecl);
6135 unvisit_body (body_p, fndecl);
6136
6137 /* Make sure input_location isn't set to something wierd. */
6138 input_location = DECL_SOURCE_LOCATION (fndecl);
6139
6140 /* Resolve callee-copies. This has to be done before processing
6141 the body so that DECL_VALUE_EXPR gets processed correctly. */
6142 parm_stmts = do_parms ? gimplify_parameters () : NULL;
6143
6144 /* Gimplify the function's body. */
6145 gimplify_stmt (body_p);
6146 body = *body_p;
6147
6148 if (!body)
6149 body = alloc_stmt_list ();
6150 else if (TREE_CODE (body) == STATEMENT_LIST)
6151 {
6152 tree t = expr_only (*body_p);
6153 if (t)
6154 body = t;
6155 }
6156
6157 /* If there isn't an outer BIND_EXPR, add one. */
6158 if (TREE_CODE (body) != BIND_EXPR)
6159 {
6160 tree b = build3 (BIND_EXPR, void_type_node, NULL_TREE,
6161 NULL_TREE, NULL_TREE);
6162 TREE_SIDE_EFFECTS (b) = 1;
6163 append_to_statement_list_force (body, &BIND_EXPR_BODY (b));
6164 body = b;
6165 }
6166
6167 /* If we had callee-copies statements, insert them at the beginning
6168 of the function. */
6169 if (parm_stmts)
6170 {
6171 append_to_statement_list_force (BIND_EXPR_BODY (body), &parm_stmts);
6172 BIND_EXPR_BODY (body) = parm_stmts;
6173 }
6174
6175 /* Unshare again, in case gimplification was sloppy. */
6176 unshare_all_trees (body);
6177
6178 *body_p = body;
6179
6180 pop_gimplify_context (body);
6181 gcc_assert (gimplify_ctxp == NULL);
6182
6183 #ifdef ENABLE_CHECKING
6184 walk_tree (body_p, check_pointer_types_r, NULL, NULL);
6185 #endif
6186
6187 timevar_pop (TV_TREE_GIMPLIFY);
6188 input_location = saved_location;
6189 }
6190
6191 /* Entry point to the gimplification pass. FNDECL is the FUNCTION_DECL
6192 node for the function we want to gimplify. */
6193
6194 void
6195 gimplify_function_tree (tree fndecl)
6196 {
6197 tree oldfn, parm, ret;
6198
6199 oldfn = current_function_decl;
6200 current_function_decl = fndecl;
6201 cfun = DECL_STRUCT_FUNCTION (fndecl);
6202 if (cfun == NULL)
6203 allocate_struct_function (fndecl);
6204
6205 for (parm = DECL_ARGUMENTS (fndecl); parm ; parm = TREE_CHAIN (parm))
6206 {
6207 /* Preliminarily mark non-addressed complex variables as eligible
6208 for promotion to gimple registers. We'll transform their uses
6209 as we find them. */
6210 if (TREE_CODE (TREE_TYPE (parm)) == COMPLEX_TYPE
6211 && !TREE_THIS_VOLATILE (parm)
6212 && !needs_to_live_in_memory (parm))
6213 DECL_COMPLEX_GIMPLE_REG_P (parm) = 1;
6214 }
6215
6216 ret = DECL_RESULT (fndecl);
6217 if (TREE_CODE (TREE_TYPE (ret)) == COMPLEX_TYPE
6218 && !needs_to_live_in_memory (ret))
6219 DECL_COMPLEX_GIMPLE_REG_P (ret) = 1;
6220
6221 gimplify_body (&DECL_SAVED_TREE (fndecl), fndecl, true);
6222
6223 /* If we're instrumenting function entry/exit, then prepend the call to
6224 the entry hook and wrap the whole function in a TRY_FINALLY_EXPR to
6225 catch the exit hook. */
6226 /* ??? Add some way to ignore exceptions for this TFE. */
6227 if (flag_instrument_function_entry_exit
6228 && ! DECL_NO_INSTRUMENT_FUNCTION_ENTRY_EXIT (fndecl))
6229 {
6230 tree tf, x, bind;
6231
6232 tf = build2 (TRY_FINALLY_EXPR, void_type_node, NULL, NULL);
6233 TREE_SIDE_EFFECTS (tf) = 1;
6234 x = DECL_SAVED_TREE (fndecl);
6235 append_to_statement_list (x, &TREE_OPERAND (tf, 0));
6236 x = implicit_built_in_decls[BUILT_IN_PROFILE_FUNC_EXIT];
6237 x = build_function_call_expr (x, NULL);
6238 append_to_statement_list (x, &TREE_OPERAND (tf, 1));
6239
6240 bind = build3 (BIND_EXPR, void_type_node, NULL, NULL, NULL);
6241 TREE_SIDE_EFFECTS (bind) = 1;
6242 x = implicit_built_in_decls[BUILT_IN_PROFILE_FUNC_ENTER];
6243 x = build_function_call_expr (x, NULL);
6244 append_to_statement_list (x, &BIND_EXPR_BODY (bind));
6245 append_to_statement_list (tf, &BIND_EXPR_BODY (bind));
6246
6247 DECL_SAVED_TREE (fndecl) = bind;
6248 }
6249
6250 current_function_decl = oldfn;
6251 cfun = oldfn ? DECL_STRUCT_FUNCTION (oldfn) : NULL;
6252 }
6253
6254 \f
6255 /* Expands EXPR to list of gimple statements STMTS. If SIMPLE is true,
6256 force the result to be either ssa_name or an invariant, otherwise
6257 just force it to be a rhs expression. If VAR is not NULL, make the
6258 base variable of the final destination be VAR if suitable. */
6259
6260 tree
6261 force_gimple_operand (tree expr, tree *stmts, bool simple, tree var)
6262 {
6263 tree t;
6264 enum gimplify_status ret;
6265 gimple_predicate gimple_test_f;
6266
6267 *stmts = NULL_TREE;
6268
6269 if (is_gimple_val (expr))
6270 return expr;
6271
6272 gimple_test_f = simple ? is_gimple_val : is_gimple_reg_rhs;
6273
6274 push_gimplify_context ();
6275 gimplify_ctxp->into_ssa = in_ssa_p;
6276
6277 if (var)
6278 expr = build2 (MODIFY_EXPR, TREE_TYPE (var), var, expr);
6279
6280 ret = gimplify_expr (&expr, stmts, NULL,
6281 gimple_test_f, fb_rvalue);
6282 gcc_assert (ret != GS_ERROR);
6283
6284 if (referenced_vars)
6285 {
6286 for (t = gimplify_ctxp->temps; t ; t = TREE_CHAIN (t))
6287 add_referenced_var (t);
6288 }
6289
6290 pop_gimplify_context (NULL);
6291
6292 return expr;
6293 }
6294
6295 /* Invokes force_gimple_operand for EXPR with parameters SIMPLE_P and VAR. If
6296 some statements are produced, emits them before BSI. */
6297
6298 tree
6299 force_gimple_operand_bsi (block_stmt_iterator *bsi, tree expr,
6300 bool simple_p, tree var)
6301 {
6302 tree stmts;
6303
6304 expr = force_gimple_operand (expr, &stmts, simple_p, var);
6305 if (stmts)
6306 bsi_insert_before (bsi, stmts, BSI_SAME_STMT);
6307
6308 return expr;
6309 }
6310
6311 #include "gt-gimplify.h"