re PR c++/23372 (Temporary aggregate copy not elided when passing parameters by value)
[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 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 };
77
78 struct gimplify_ctx
79 {
80 struct gimplify_ctx *prev_context;
81
82 tree current_bind_expr;
83 tree temps;
84 tree conditional_cleanups;
85 tree exit_label;
86 tree return_temp;
87
88 VEC(tree,heap) *case_labels;
89 /* The formal temporary table. Should this be persistent? */
90 htab_t temp_htab;
91
92 int conditions;
93 bool save_stack;
94 bool into_ssa;
95 };
96
97 static struct gimplify_ctx *gimplify_ctxp;
98 static struct gimplify_omp_ctx *gimplify_omp_ctxp;
99
100
101
102 /* Formal (expression) temporary table handling: Multiple occurrences of
103 the same scalar expression are evaluated into the same temporary. */
104
105 typedef struct gimple_temp_hash_elt
106 {
107 tree val; /* Key */
108 tree temp; /* Value */
109 } elt_t;
110
111 /* Forward declarations. */
112 static enum gimplify_status gimplify_compound_expr (tree *, tree *, bool);
113 #ifdef ENABLE_CHECKING
114 static bool cpt_same_type (tree a, tree b);
115 #endif
116
117
118 /* Return a hash value for a formal temporary table entry. */
119
120 static hashval_t
121 gimple_tree_hash (const void *p)
122 {
123 tree t = ((const elt_t *) p)->val;
124 return iterative_hash_expr (t, 0);
125 }
126
127 /* Compare two formal temporary table entries. */
128
129 static int
130 gimple_tree_eq (const void *p1, const void *p2)
131 {
132 tree t1 = ((const elt_t *) p1)->val;
133 tree t2 = ((const elt_t *) p2)->val;
134 enum tree_code code = TREE_CODE (t1);
135
136 if (TREE_CODE (t2) != code
137 || TREE_TYPE (t1) != TREE_TYPE (t2))
138 return 0;
139
140 if (!operand_equal_p (t1, t2, 0))
141 return 0;
142
143 /* Only allow them to compare equal if they also hash equal; otherwise
144 results are nondeterminate, and we fail bootstrap comparison. */
145 gcc_assert (gimple_tree_hash (p1) == gimple_tree_hash (p2));
146
147 return 1;
148 }
149
150 /* Set up a context for the gimplifier. */
151
152 void
153 push_gimplify_context (void)
154 {
155 struct gimplify_ctx *c;
156
157 c = (struct gimplify_ctx *) xcalloc (1, sizeof (struct gimplify_ctx));
158 c->prev_context = gimplify_ctxp;
159 if (optimize)
160 c->temp_htab = htab_create (1000, gimple_tree_hash, gimple_tree_eq, free);
161
162 gimplify_ctxp = c;
163 }
164
165 /* Tear down a context for the gimplifier. If BODY is non-null, then
166 put the temporaries into the outer BIND_EXPR. Otherwise, put them
167 in the unexpanded_var_list. */
168
169 void
170 pop_gimplify_context (tree body)
171 {
172 struct gimplify_ctx *c = gimplify_ctxp;
173 tree t;
174
175 gcc_assert (c && !c->current_bind_expr);
176 gimplify_ctxp = c->prev_context;
177
178 for (t = c->temps; t ; t = TREE_CHAIN (t))
179 DECL_GIMPLE_FORMAL_TEMP_P (t) = 0;
180
181 if (body)
182 declare_tmp_vars (c->temps, body);
183 else
184 record_vars (c->temps);
185
186 if (optimize)
187 htab_delete (c->temp_htab);
188 free (c);
189 }
190
191 static void
192 gimple_push_bind_expr (tree bind)
193 {
194 TREE_CHAIN (bind) = gimplify_ctxp->current_bind_expr;
195 gimplify_ctxp->current_bind_expr = bind;
196 }
197
198 static void
199 gimple_pop_bind_expr (void)
200 {
201 gimplify_ctxp->current_bind_expr
202 = TREE_CHAIN (gimplify_ctxp->current_bind_expr);
203 }
204
205 tree
206 gimple_current_bind_expr (void)
207 {
208 return gimplify_ctxp->current_bind_expr;
209 }
210
211 /* Returns true iff there is a COND_EXPR between us and the innermost
212 CLEANUP_POINT_EXPR. This info is used by gimple_push_cleanup. */
213
214 static bool
215 gimple_conditional_context (void)
216 {
217 return gimplify_ctxp->conditions > 0;
218 }
219
220 /* Note that we've entered a COND_EXPR. */
221
222 static void
223 gimple_push_condition (void)
224 {
225 #ifdef ENABLE_CHECKING
226 if (gimplify_ctxp->conditions == 0)
227 gcc_assert (!gimplify_ctxp->conditional_cleanups);
228 #endif
229 ++(gimplify_ctxp->conditions);
230 }
231
232 /* Note that we've left a COND_EXPR. If we're back at unconditional scope
233 now, add any conditional cleanups we've seen to the prequeue. */
234
235 static void
236 gimple_pop_condition (tree *pre_p)
237 {
238 int conds = --(gimplify_ctxp->conditions);
239
240 gcc_assert (conds >= 0);
241 if (conds == 0)
242 {
243 append_to_statement_list (gimplify_ctxp->conditional_cleanups, pre_p);
244 gimplify_ctxp->conditional_cleanups = NULL_TREE;
245 }
246 }
247
248 /* A stable comparison routine for use with splay trees and DECLs. */
249
250 static int
251 splay_tree_compare_decl_uid (splay_tree_key xa, splay_tree_key xb)
252 {
253 tree a = (tree) xa;
254 tree b = (tree) xb;
255
256 return DECL_UID (a) - DECL_UID (b);
257 }
258
259 /* Create a new omp construct that deals with variable remapping. */
260
261 static struct gimplify_omp_ctx *
262 new_omp_context (bool is_parallel)
263 {
264 struct gimplify_omp_ctx *c;
265
266 c = XCNEW (struct gimplify_omp_ctx);
267 c->outer_context = gimplify_omp_ctxp;
268 c->variables = splay_tree_new (splay_tree_compare_decl_uid, 0, 0);
269 c->privatized_types = pointer_set_create ();
270 c->location = input_location;
271 c->is_parallel = is_parallel;
272 c->default_kind = OMP_CLAUSE_DEFAULT_SHARED;
273
274 return c;
275 }
276
277 /* Destroy an omp construct that deals with variable remapping. */
278
279 static void
280 delete_omp_context (struct gimplify_omp_ctx *c)
281 {
282 splay_tree_delete (c->variables);
283 pointer_set_destroy (c->privatized_types);
284 XDELETE (c);
285 }
286
287 static void omp_add_variable (struct gimplify_omp_ctx *, tree, unsigned int);
288 static bool omp_notice_variable (struct gimplify_omp_ctx *, tree, bool);
289
290 /* A subroutine of append_to_statement_list{,_force}. T is not NULL. */
291
292 static void
293 append_to_statement_list_1 (tree t, tree *list_p)
294 {
295 tree list = *list_p;
296 tree_stmt_iterator i;
297
298 if (!list)
299 {
300 if (t && TREE_CODE (t) == STATEMENT_LIST)
301 {
302 *list_p = t;
303 return;
304 }
305 *list_p = list = alloc_stmt_list ();
306 }
307
308 i = tsi_last (list);
309 tsi_link_after (&i, t, TSI_CONTINUE_LINKING);
310 }
311
312 /* Add T to the end of the list container pointed to by LIST_P.
313 If T is an expression with no effects, it is ignored. */
314
315 void
316 append_to_statement_list (tree t, tree *list_p)
317 {
318 if (t && TREE_SIDE_EFFECTS (t))
319 append_to_statement_list_1 (t, list_p);
320 }
321
322 /* Similar, but the statement is always added, regardless of side effects. */
323
324 void
325 append_to_statement_list_force (tree t, tree *list_p)
326 {
327 if (t != NULL_TREE)
328 append_to_statement_list_1 (t, list_p);
329 }
330
331 /* Both gimplify the statement T and append it to LIST_P. */
332
333 void
334 gimplify_and_add (tree t, tree *list_p)
335 {
336 gimplify_stmt (&t);
337 append_to_statement_list (t, list_p);
338 }
339
340 /* Strip off a legitimate source ending from the input string NAME of
341 length LEN. Rather than having to know the names used by all of
342 our front ends, we strip off an ending of a period followed by
343 up to five characters. (Java uses ".class".) */
344
345 static inline void
346 remove_suffix (char *name, int len)
347 {
348 int i;
349
350 for (i = 2; i < 8 && len > i; i++)
351 {
352 if (name[len - i] == '.')
353 {
354 name[len - i] = '\0';
355 break;
356 }
357 }
358 }
359
360 /* Create a nameless artificial label and put it in the current function
361 context. Returns the newly created label. */
362
363 tree
364 create_artificial_label (void)
365 {
366 tree lab = build_decl (LABEL_DECL, NULL_TREE, void_type_node);
367
368 DECL_ARTIFICIAL (lab) = 1;
369 DECL_IGNORED_P (lab) = 1;
370 DECL_CONTEXT (lab) = current_function_decl;
371 return lab;
372 }
373
374 /* Subroutine for find_single_pointer_decl. */
375
376 static tree
377 find_single_pointer_decl_1 (tree *tp, int *walk_subtrees ATTRIBUTE_UNUSED,
378 void *data)
379 {
380 tree *pdecl = (tree *) data;
381
382 if (DECL_P (*tp) && POINTER_TYPE_P (TREE_TYPE (*tp)))
383 {
384 if (*pdecl)
385 {
386 /* We already found a pointer decl; return anything other
387 than NULL_TREE to unwind from walk_tree signalling that
388 we have a duplicate. */
389 return *tp;
390 }
391 *pdecl = *tp;
392 }
393
394 return NULL_TREE;
395 }
396
397 /* Find the single DECL of pointer type in the tree T and return it.
398 If there are zero or more than one such DECLs, return NULL. */
399
400 static tree
401 find_single_pointer_decl (tree t)
402 {
403 tree decl = NULL_TREE;
404
405 if (walk_tree (&t, find_single_pointer_decl_1, &decl, NULL))
406 {
407 /* find_single_pointer_decl_1 returns a non-zero value, causing
408 walk_tree to return a non-zero value, to indicate that it
409 found more than one pointer DECL. */
410 return NULL_TREE;
411 }
412
413 return decl;
414 }
415
416 /* Create a new temporary name with PREFIX. Returns an identifier. */
417
418 static GTY(()) unsigned int tmp_var_id_num;
419
420 tree
421 create_tmp_var_name (const char *prefix)
422 {
423 char *tmp_name;
424
425 if (prefix)
426 {
427 char *preftmp = ASTRDUP (prefix);
428
429 remove_suffix (preftmp, strlen (preftmp));
430 prefix = preftmp;
431 }
432
433 ASM_FORMAT_PRIVATE_NAME (tmp_name, prefix ? prefix : "T", tmp_var_id_num++);
434 return get_identifier (tmp_name);
435 }
436
437
438 /* Create a new temporary variable declaration of type TYPE.
439 Does NOT push it into the current binding. */
440
441 tree
442 create_tmp_var_raw (tree type, const char *prefix)
443 {
444 tree tmp_var;
445 tree new_type;
446
447 /* Make the type of the variable writable. */
448 new_type = build_type_variant (type, 0, 0);
449 TYPE_ATTRIBUTES (new_type) = TYPE_ATTRIBUTES (type);
450
451 tmp_var = build_decl (VAR_DECL, prefix ? create_tmp_var_name (prefix) : NULL,
452 type);
453
454 /* The variable was declared by the compiler. */
455 DECL_ARTIFICIAL (tmp_var) = 1;
456 /* And we don't want debug info for it. */
457 DECL_IGNORED_P (tmp_var) = 1;
458
459 /* Make the variable writable. */
460 TREE_READONLY (tmp_var) = 0;
461
462 DECL_EXTERNAL (tmp_var) = 0;
463 TREE_STATIC (tmp_var) = 0;
464 TREE_USED (tmp_var) = 1;
465
466 return tmp_var;
467 }
468
469 /* Create a new temporary variable declaration of type TYPE. DOES push the
470 variable into the current binding. Further, assume that this is called
471 only from gimplification or optimization, at which point the creation of
472 certain types are bugs. */
473
474 tree
475 create_tmp_var (tree type, const char *prefix)
476 {
477 tree tmp_var;
478
479 /* We don't allow types that are addressable (meaning we can't make copies),
480 incomplete, or of variable size. */
481 gcc_assert (!TREE_ADDRESSABLE (type)
482 && COMPLETE_TYPE_P (type)
483 && TREE_CODE (TYPE_SIZE_UNIT (type)) == INTEGER_CST);
484
485 tmp_var = create_tmp_var_raw (type, prefix);
486 gimple_add_tmp_var (tmp_var);
487 return tmp_var;
488 }
489
490 /* Given a tree, try to return a useful variable name that we can use
491 to prefix a temporary that is being assigned the value of the tree.
492 I.E. given <temp> = &A, return A. */
493
494 const char *
495 get_name (tree t)
496 {
497 tree stripped_decl;
498
499 stripped_decl = t;
500 STRIP_NOPS (stripped_decl);
501 if (DECL_P (stripped_decl) && DECL_NAME (stripped_decl))
502 return IDENTIFIER_POINTER (DECL_NAME (stripped_decl));
503 else
504 {
505 switch (TREE_CODE (stripped_decl))
506 {
507 case ADDR_EXPR:
508 return get_name (TREE_OPERAND (stripped_decl, 0));
509 break;
510 default:
511 return NULL;
512 }
513 }
514 }
515
516 /* Create a temporary with a name derived from VAL. Subroutine of
517 lookup_tmp_var; nobody else should call this function. */
518
519 static inline tree
520 create_tmp_from_val (tree val)
521 {
522 return create_tmp_var (TYPE_MAIN_VARIANT (TREE_TYPE (val)), get_name (val));
523 }
524
525 /* Create a temporary to hold the value of VAL. If IS_FORMAL, try to reuse
526 an existing expression temporary. */
527
528 static tree
529 lookup_tmp_var (tree val, bool is_formal)
530 {
531 tree ret;
532
533 /* If not optimizing, never really reuse a temporary. local-alloc
534 won't allocate any variable that is used in more than one basic
535 block, which means it will go into memory, causing much extra
536 work in reload and final and poorer code generation, outweighing
537 the extra memory allocation here. */
538 if (!optimize || !is_formal || TREE_SIDE_EFFECTS (val))
539 ret = create_tmp_from_val (val);
540 else
541 {
542 elt_t elt, *elt_p;
543 void **slot;
544
545 elt.val = val;
546 slot = htab_find_slot (gimplify_ctxp->temp_htab, (void *)&elt, INSERT);
547 if (*slot == NULL)
548 {
549 elt_p = XNEW (elt_t);
550 elt_p->val = val;
551 elt_p->temp = ret = create_tmp_from_val (val);
552 *slot = (void *) elt_p;
553 }
554 else
555 {
556 elt_p = (elt_t *) *slot;
557 ret = elt_p->temp;
558 }
559 }
560
561 if (is_formal)
562 DECL_GIMPLE_FORMAL_TEMP_P (ret) = 1;
563
564 return ret;
565 }
566
567 /* Returns a formal temporary variable initialized with VAL. PRE_P is as
568 in gimplify_expr. Only use this function if:
569
570 1) The value of the unfactored expression represented by VAL will not
571 change between the initialization and use of the temporary, and
572 2) The temporary will not be otherwise modified.
573
574 For instance, #1 means that this is inappropriate for SAVE_EXPR temps,
575 and #2 means it is inappropriate for && temps.
576
577 For other cases, use get_initialized_tmp_var instead. */
578
579 static tree
580 internal_get_tmp_var (tree val, tree *pre_p, tree *post_p, bool is_formal)
581 {
582 tree t, mod;
583
584 gimplify_expr (&val, pre_p, post_p, is_gimple_formal_tmp_rhs, fb_rvalue);
585
586 t = lookup_tmp_var (val, is_formal);
587
588 if (is_formal)
589 {
590 tree u = find_single_pointer_decl (val);
591
592 if (u && TREE_CODE (u) == VAR_DECL && DECL_BASED_ON_RESTRICT_P (u))
593 u = DECL_GET_RESTRICT_BASE (u);
594 if (u && TYPE_RESTRICT (TREE_TYPE (u)))
595 {
596 if (DECL_BASED_ON_RESTRICT_P (t))
597 gcc_assert (u == DECL_GET_RESTRICT_BASE (t));
598 else
599 {
600 DECL_BASED_ON_RESTRICT_P (t) = 1;
601 SET_DECL_RESTRICT_BASE (t, u);
602 }
603 }
604 }
605
606 if (TREE_CODE (TREE_TYPE (t)) == COMPLEX_TYPE)
607 DECL_COMPLEX_GIMPLE_REG_P (t) = 1;
608
609 mod = build2 (MODIFY_EXPR, TREE_TYPE (t), t, val);
610
611 if (EXPR_HAS_LOCATION (val))
612 SET_EXPR_LOCUS (mod, EXPR_LOCUS (val));
613 else
614 SET_EXPR_LOCATION (mod, input_location);
615
616 /* gimplify_modify_expr might want to reduce this further. */
617 gimplify_and_add (mod, pre_p);
618
619 /* If we're gimplifying into ssa, gimplify_modify_expr will have
620 given our temporary an ssa name. Find and return it. */
621 if (gimplify_ctxp->into_ssa)
622 t = TREE_OPERAND (mod, 0);
623
624 return t;
625 }
626
627 /* Returns a formal temporary variable initialized with VAL. PRE_P
628 points to a statement list where side-effects needed to compute VAL
629 should be stored. */
630
631 tree
632 get_formal_tmp_var (tree val, tree *pre_p)
633 {
634 return internal_get_tmp_var (val, pre_p, NULL, true);
635 }
636
637 /* Returns a temporary variable initialized with VAL. PRE_P and POST_P
638 are as in gimplify_expr. */
639
640 tree
641 get_initialized_tmp_var (tree val, tree *pre_p, tree *post_p)
642 {
643 return internal_get_tmp_var (val, pre_p, post_p, false);
644 }
645
646 /* Declares all the variables in VARS in SCOPE. */
647
648 void
649 declare_tmp_vars (tree vars, tree scope)
650 {
651 tree last = vars;
652 if (last)
653 {
654 tree temps;
655
656 /* C99 mode puts the default 'return 0;' for main outside the outer
657 braces. So drill down until we find an actual scope. */
658 while (TREE_CODE (scope) == COMPOUND_EXPR)
659 scope = TREE_OPERAND (scope, 0);
660
661 gcc_assert (TREE_CODE (scope) == BIND_EXPR);
662
663 temps = nreverse (last);
664 TREE_CHAIN (last) = BIND_EXPR_VARS (scope);
665 BIND_EXPR_VARS (scope) = temps;
666 }
667 }
668
669 void
670 gimple_add_tmp_var (tree tmp)
671 {
672 gcc_assert (!TREE_CHAIN (tmp) && !DECL_SEEN_IN_BIND_EXPR_P (tmp));
673
674 DECL_CONTEXT (tmp) = current_function_decl;
675 DECL_SEEN_IN_BIND_EXPR_P (tmp) = 1;
676
677 if (gimplify_ctxp)
678 {
679 TREE_CHAIN (tmp) = gimplify_ctxp->temps;
680 gimplify_ctxp->temps = tmp;
681
682 /* Mark temporaries local within the nearest enclosing parallel. */
683 if (gimplify_omp_ctxp)
684 {
685 struct gimplify_omp_ctx *ctx = gimplify_omp_ctxp;
686 while (ctx && !ctx->is_parallel)
687 ctx = ctx->outer_context;
688 if (ctx)
689 omp_add_variable (ctx, tmp, GOVD_LOCAL | GOVD_SEEN);
690 }
691 }
692 else if (cfun)
693 record_vars (tmp);
694 else
695 declare_tmp_vars (tmp, DECL_SAVED_TREE (current_function_decl));
696 }
697
698 /* Determines whether to assign a locus to the statement STMT. */
699
700 static bool
701 should_carry_locus_p (tree stmt)
702 {
703 /* Don't emit a line note for a label. We particularly don't want to
704 emit one for the break label, since it doesn't actually correspond
705 to the beginning of the loop/switch. */
706 if (TREE_CODE (stmt) == LABEL_EXPR)
707 return false;
708
709 /* Do not annotate empty statements, since it confuses gcov. */
710 if (!TREE_SIDE_EFFECTS (stmt))
711 return false;
712
713 return true;
714 }
715
716 static void
717 annotate_one_with_locus (tree t, location_t locus)
718 {
719 if (EXPR_P (t) && ! EXPR_HAS_LOCATION (t) && should_carry_locus_p (t))
720 SET_EXPR_LOCATION (t, locus);
721 }
722
723 void
724 annotate_all_with_locus (tree *stmt_p, location_t locus)
725 {
726 tree_stmt_iterator i;
727
728 if (!*stmt_p)
729 return;
730
731 for (i = tsi_start (*stmt_p); !tsi_end_p (i); tsi_next (&i))
732 {
733 tree t = tsi_stmt (i);
734
735 /* Assuming we've already been gimplified, we shouldn't
736 see nested chaining constructs anymore. */
737 gcc_assert (TREE_CODE (t) != STATEMENT_LIST
738 && TREE_CODE (t) != COMPOUND_EXPR);
739
740 annotate_one_with_locus (t, locus);
741 }
742 }
743
744 /* Similar to copy_tree_r() but do not copy SAVE_EXPR or TARGET_EXPR nodes.
745 These nodes model computations that should only be done once. If we
746 were to unshare something like SAVE_EXPR(i++), the gimplification
747 process would create wrong code. */
748
749 static tree
750 mostly_copy_tree_r (tree *tp, int *walk_subtrees, void *data)
751 {
752 enum tree_code code = TREE_CODE (*tp);
753 /* Don't unshare types, decls, constants and SAVE_EXPR nodes. */
754 if (TREE_CODE_CLASS (code) == tcc_type
755 || TREE_CODE_CLASS (code) == tcc_declaration
756 || TREE_CODE_CLASS (code) == tcc_constant
757 || code == SAVE_EXPR || code == TARGET_EXPR
758 /* We can't do anything sensible with a BLOCK used as an expression,
759 but we also can't just die when we see it because of non-expression
760 uses. So just avert our eyes and cross our fingers. Silly Java. */
761 || code == BLOCK)
762 *walk_subtrees = 0;
763 else
764 {
765 gcc_assert (code != BIND_EXPR);
766 copy_tree_r (tp, walk_subtrees, data);
767 }
768
769 return NULL_TREE;
770 }
771
772 /* Callback for walk_tree to unshare most of the shared trees rooted at
773 *TP. If *TP has been visited already (i.e., TREE_VISITED (*TP) == 1),
774 then *TP is deep copied by calling copy_tree_r.
775
776 This unshares the same trees as copy_tree_r with the exception of
777 SAVE_EXPR nodes. These nodes model computations that should only be
778 done once. If we were to unshare something like SAVE_EXPR(i++), the
779 gimplification process would create wrong code. */
780
781 static tree
782 copy_if_shared_r (tree *tp, int *walk_subtrees ATTRIBUTE_UNUSED,
783 void *data ATTRIBUTE_UNUSED)
784 {
785 tree t = *tp;
786 enum tree_code code = TREE_CODE (t);
787
788 /* Skip types, decls, and constants. But we do want to look at their
789 types and the bounds of types. Mark them as visited so we properly
790 unmark their subtrees on the unmark pass. If we've already seen them,
791 don't look down further. */
792 if (TREE_CODE_CLASS (code) == tcc_type
793 || TREE_CODE_CLASS (code) == tcc_declaration
794 || TREE_CODE_CLASS (code) == tcc_constant)
795 {
796 if (TREE_VISITED (t))
797 *walk_subtrees = 0;
798 else
799 TREE_VISITED (t) = 1;
800 }
801
802 /* If this node has been visited already, unshare it and don't look
803 any deeper. */
804 else if (TREE_VISITED (t))
805 {
806 walk_tree (tp, mostly_copy_tree_r, NULL, NULL);
807 *walk_subtrees = 0;
808 }
809
810 /* Otherwise, mark the tree as visited and keep looking. */
811 else
812 TREE_VISITED (t) = 1;
813
814 return NULL_TREE;
815 }
816
817 static tree
818 unmark_visited_r (tree *tp, int *walk_subtrees ATTRIBUTE_UNUSED,
819 void *data ATTRIBUTE_UNUSED)
820 {
821 if (TREE_VISITED (*tp))
822 TREE_VISITED (*tp) = 0;
823 else
824 *walk_subtrees = 0;
825
826 return NULL_TREE;
827 }
828
829 /* Unshare all the trees in BODY_P, a pointer into the body of FNDECL, and the
830 bodies of any nested functions if we are unsharing the entire body of
831 FNDECL. */
832
833 static void
834 unshare_body (tree *body_p, tree fndecl)
835 {
836 struct cgraph_node *cgn = cgraph_node (fndecl);
837
838 walk_tree (body_p, copy_if_shared_r, NULL, NULL);
839 if (body_p == &DECL_SAVED_TREE (fndecl))
840 for (cgn = cgn->nested; cgn; cgn = cgn->next_nested)
841 unshare_body (&DECL_SAVED_TREE (cgn->decl), cgn->decl);
842 }
843
844 /* Likewise, but mark all trees as not visited. */
845
846 static void
847 unvisit_body (tree *body_p, tree fndecl)
848 {
849 struct cgraph_node *cgn = cgraph_node (fndecl);
850
851 walk_tree (body_p, unmark_visited_r, NULL, NULL);
852 if (body_p == &DECL_SAVED_TREE (fndecl))
853 for (cgn = cgn->nested; cgn; cgn = cgn->next_nested)
854 unvisit_body (&DECL_SAVED_TREE (cgn->decl), cgn->decl);
855 }
856
857 /* Unshare T and all the trees reached from T via TREE_CHAIN. */
858
859 static void
860 unshare_all_trees (tree t)
861 {
862 walk_tree (&t, copy_if_shared_r, NULL, NULL);
863 walk_tree (&t, unmark_visited_r, NULL, NULL);
864 }
865
866 /* Unconditionally make an unshared copy of EXPR. This is used when using
867 stored expressions which span multiple functions, such as BINFO_VTABLE,
868 as the normal unsharing process can't tell that they're shared. */
869
870 tree
871 unshare_expr (tree expr)
872 {
873 walk_tree (&expr, mostly_copy_tree_r, NULL, NULL);
874 return expr;
875 }
876
877 /* A terser interface for building a representation of an exception
878 specification. */
879
880 tree
881 gimple_build_eh_filter (tree body, tree allowed, tree failure)
882 {
883 tree t;
884
885 /* FIXME should the allowed types go in TREE_TYPE? */
886 t = build2 (EH_FILTER_EXPR, void_type_node, allowed, NULL_TREE);
887 append_to_statement_list (failure, &EH_FILTER_FAILURE (t));
888
889 t = build2 (TRY_CATCH_EXPR, void_type_node, NULL_TREE, t);
890 append_to_statement_list (body, &TREE_OPERAND (t, 0));
891
892 return t;
893 }
894
895 \f
896 /* WRAPPER is a code such as BIND_EXPR or CLEANUP_POINT_EXPR which can both
897 contain statements and have a value. Assign its value to a temporary
898 and give it void_type_node. Returns the temporary, or NULL_TREE if
899 WRAPPER was already void. */
900
901 tree
902 voidify_wrapper_expr (tree wrapper, tree temp)
903 {
904 if (!VOID_TYPE_P (TREE_TYPE (wrapper)))
905 {
906 tree *p, sub = wrapper;
907
908 restart:
909 /* Set p to point to the body of the wrapper. */
910 switch (TREE_CODE (sub))
911 {
912 case BIND_EXPR:
913 /* For a BIND_EXPR, the body is operand 1. */
914 p = &BIND_EXPR_BODY (sub);
915 break;
916
917 default:
918 p = &TREE_OPERAND (sub, 0);
919 break;
920 }
921
922 /* Advance to the last statement. Set all container types to void. */
923 if (TREE_CODE (*p) == STATEMENT_LIST)
924 {
925 tree_stmt_iterator i = tsi_last (*p);
926 p = tsi_end_p (i) ? NULL : tsi_stmt_ptr (i);
927 }
928 else
929 {
930 for (; TREE_CODE (*p) == COMPOUND_EXPR; p = &TREE_OPERAND (*p, 1))
931 {
932 TREE_SIDE_EFFECTS (*p) = 1;
933 TREE_TYPE (*p) = void_type_node;
934 }
935 }
936
937 if (p == NULL || IS_EMPTY_STMT (*p))
938 ;
939 /* Look through exception handling. */
940 else if (TREE_CODE (*p) == TRY_FINALLY_EXPR
941 || TREE_CODE (*p) == TRY_CATCH_EXPR)
942 {
943 sub = *p;
944 goto restart;
945 }
946 /* The C++ frontend already did this for us. */
947 else if (TREE_CODE (*p) == INIT_EXPR
948 || TREE_CODE (*p) == TARGET_EXPR)
949 temp = TREE_OPERAND (*p, 0);
950 /* If we're returning a dereference, move the dereference
951 outside the wrapper. */
952 else if (TREE_CODE (*p) == INDIRECT_REF)
953 {
954 tree ptr = TREE_OPERAND (*p, 0);
955 temp = create_tmp_var (TREE_TYPE (ptr), "retval");
956 *p = build2 (MODIFY_EXPR, TREE_TYPE (ptr), temp, ptr);
957 temp = build1 (INDIRECT_REF, TREE_TYPE (TREE_TYPE (temp)), temp);
958 /* If this is a BIND_EXPR for a const inline function, it might not
959 have TREE_SIDE_EFFECTS set. That is no longer accurate. */
960 TREE_SIDE_EFFECTS (wrapper) = 1;
961 }
962 else
963 {
964 if (!temp)
965 temp = create_tmp_var (TREE_TYPE (wrapper), "retval");
966 *p = build2 (MODIFY_EXPR, TREE_TYPE (temp), temp, *p);
967 TREE_SIDE_EFFECTS (wrapper) = 1;
968 }
969
970 TREE_TYPE (wrapper) = void_type_node;
971 return temp;
972 }
973
974 return NULL_TREE;
975 }
976
977 /* Prepare calls to builtins to SAVE and RESTORE the stack as well as
978 a temporary through which they communicate. */
979
980 static void
981 build_stack_save_restore (tree *save, tree *restore)
982 {
983 tree save_call, tmp_var;
984
985 save_call =
986 build_function_call_expr (implicit_built_in_decls[BUILT_IN_STACK_SAVE],
987 NULL_TREE);
988 tmp_var = create_tmp_var (ptr_type_node, "saved_stack");
989
990 *save = build2 (MODIFY_EXPR, ptr_type_node, tmp_var, save_call);
991 *restore =
992 build_function_call_expr (implicit_built_in_decls[BUILT_IN_STACK_RESTORE],
993 tree_cons (NULL_TREE, tmp_var, NULL_TREE));
994 }
995
996 /* Gimplify a BIND_EXPR. Just voidify and recurse. */
997
998 static enum gimplify_status
999 gimplify_bind_expr (tree *expr_p, tree temp, tree *pre_p)
1000 {
1001 tree bind_expr = *expr_p;
1002 bool old_save_stack = gimplify_ctxp->save_stack;
1003 tree t;
1004
1005 temp = voidify_wrapper_expr (bind_expr, temp);
1006
1007 /* Mark variables seen in this bind expr. */
1008 for (t = BIND_EXPR_VARS (bind_expr); t ; t = TREE_CHAIN (t))
1009 {
1010 if (TREE_CODE (t) == VAR_DECL)
1011 DECL_SEEN_IN_BIND_EXPR_P (t) = 1;
1012
1013 /* Preliminarily mark non-addressed complex variables as eligible
1014 for promotion to gimple registers. We'll transform their uses
1015 as we find them. */
1016 if (TREE_CODE (TREE_TYPE (t)) == COMPLEX_TYPE
1017 && !TREE_THIS_VOLATILE (t)
1018 && (TREE_CODE (t) == VAR_DECL && !DECL_HARD_REGISTER (t))
1019 && !needs_to_live_in_memory (t))
1020 DECL_COMPLEX_GIMPLE_REG_P (t) = 1;
1021 }
1022
1023 /* Mark variables seen in this bind expr as locals. */
1024 if (gimplify_omp_ctxp)
1025 {
1026 struct gimplify_omp_ctx *ctx = gimplify_omp_ctxp;
1027
1028 for (t = BIND_EXPR_VARS (bind_expr); t ; t = TREE_CHAIN (t))
1029 if (TREE_CODE (t) == VAR_DECL && !is_global_var (t))
1030 omp_add_variable (ctx, t, GOVD_LOCAL | GOVD_SEEN);
1031 }
1032
1033 gimple_push_bind_expr (bind_expr);
1034 gimplify_ctxp->save_stack = false;
1035
1036 gimplify_to_stmt_list (&BIND_EXPR_BODY (bind_expr));
1037
1038 if (gimplify_ctxp->save_stack)
1039 {
1040 tree stack_save, stack_restore;
1041
1042 /* Save stack on entry and restore it on exit. Add a try_finally
1043 block to achieve this. Note that mudflap depends on the
1044 format of the emitted code: see mx_register_decls(). */
1045 build_stack_save_restore (&stack_save, &stack_restore);
1046
1047 t = build2 (TRY_FINALLY_EXPR, void_type_node,
1048 BIND_EXPR_BODY (bind_expr), NULL_TREE);
1049 append_to_statement_list (stack_restore, &TREE_OPERAND (t, 1));
1050
1051 BIND_EXPR_BODY (bind_expr) = NULL_TREE;
1052 append_to_statement_list (stack_save, &BIND_EXPR_BODY (bind_expr));
1053 append_to_statement_list (t, &BIND_EXPR_BODY (bind_expr));
1054 }
1055
1056 gimplify_ctxp->save_stack = old_save_stack;
1057 gimple_pop_bind_expr ();
1058
1059 if (temp)
1060 {
1061 *expr_p = temp;
1062 append_to_statement_list (bind_expr, pre_p);
1063 return GS_OK;
1064 }
1065 else
1066 return GS_ALL_DONE;
1067 }
1068
1069 /* Gimplify a RETURN_EXPR. If the expression to be returned is not a
1070 GIMPLE value, it is assigned to a new temporary and the statement is
1071 re-written to return the temporary.
1072
1073 PRE_P points to the list where side effects that must happen before
1074 STMT should be stored. */
1075
1076 static enum gimplify_status
1077 gimplify_return_expr (tree stmt, tree *pre_p)
1078 {
1079 tree ret_expr = TREE_OPERAND (stmt, 0);
1080 tree result_decl, result;
1081
1082 if (!ret_expr || TREE_CODE (ret_expr) == RESULT_DECL
1083 || ret_expr == error_mark_node)
1084 return GS_ALL_DONE;
1085
1086 if (VOID_TYPE_P (TREE_TYPE (TREE_TYPE (current_function_decl))))
1087 result_decl = NULL_TREE;
1088 else
1089 {
1090 result_decl = TREE_OPERAND (ret_expr, 0);
1091 if (TREE_CODE (result_decl) == INDIRECT_REF)
1092 /* See through a return by reference. */
1093 result_decl = TREE_OPERAND (result_decl, 0);
1094
1095 gcc_assert ((TREE_CODE (ret_expr) == MODIFY_EXPR
1096 || TREE_CODE (ret_expr) == INIT_EXPR)
1097 && TREE_CODE (result_decl) == RESULT_DECL);
1098 }
1099
1100 /* If aggregate_value_p is true, then we can return the bare RESULT_DECL.
1101 Recall that aggregate_value_p is FALSE for any aggregate type that is
1102 returned in registers. If we're returning values in registers, then
1103 we don't want to extend the lifetime of the RESULT_DECL, particularly
1104 across another call. In addition, for those aggregates for which
1105 hard_function_value generates a PARALLEL, we'll die during normal
1106 expansion of structure assignments; there's special code in expand_return
1107 to handle this case that does not exist in expand_expr. */
1108 if (!result_decl
1109 || aggregate_value_p (result_decl, TREE_TYPE (current_function_decl)))
1110 result = result_decl;
1111 else if (gimplify_ctxp->return_temp)
1112 result = gimplify_ctxp->return_temp;
1113 else
1114 {
1115 result = create_tmp_var (TREE_TYPE (result_decl), NULL);
1116
1117 /* ??? With complex control flow (usually involving abnormal edges),
1118 we can wind up warning about an uninitialized value for this. Due
1119 to how this variable is constructed and initialized, this is never
1120 true. Give up and never warn. */
1121 TREE_NO_WARNING (result) = 1;
1122
1123 gimplify_ctxp->return_temp = result;
1124 }
1125
1126 /* Smash the lhs of the MODIFY_EXPR to the temporary we plan to use.
1127 Then gimplify the whole thing. */
1128 if (result != result_decl)
1129 TREE_OPERAND (ret_expr, 0) = result;
1130
1131 gimplify_and_add (TREE_OPERAND (stmt, 0), pre_p);
1132
1133 /* If we didn't use a temporary, then the result is just the result_decl.
1134 Otherwise we need a simple copy. This should already be gimple. */
1135 if (result == result_decl)
1136 ret_expr = result;
1137 else
1138 ret_expr = build2 (MODIFY_EXPR, TREE_TYPE (result), result_decl, result);
1139 TREE_OPERAND (stmt, 0) = ret_expr;
1140
1141 return GS_ALL_DONE;
1142 }
1143
1144 /* Gimplifies a DECL_EXPR node *STMT_P by making any necessary allocation
1145 and initialization explicit. */
1146
1147 static enum gimplify_status
1148 gimplify_decl_expr (tree *stmt_p)
1149 {
1150 tree stmt = *stmt_p;
1151 tree decl = DECL_EXPR_DECL (stmt);
1152
1153 *stmt_p = NULL_TREE;
1154
1155 if (TREE_TYPE (decl) == error_mark_node)
1156 return GS_ERROR;
1157
1158 if ((TREE_CODE (decl) == TYPE_DECL
1159 || TREE_CODE (decl) == VAR_DECL)
1160 && !TYPE_SIZES_GIMPLIFIED (TREE_TYPE (decl)))
1161 gimplify_type_sizes (TREE_TYPE (decl), stmt_p);
1162
1163 if (TREE_CODE (decl) == VAR_DECL && !DECL_EXTERNAL (decl))
1164 {
1165 tree init = DECL_INITIAL (decl);
1166
1167 if (!TREE_CONSTANT (DECL_SIZE (decl)))
1168 {
1169 /* This is a variable-sized decl. Simplify its size and mark it
1170 for deferred expansion. Note that mudflap depends on the format
1171 of the emitted code: see mx_register_decls(). */
1172 tree t, args, addr, ptr_type;
1173
1174 gimplify_one_sizepos (&DECL_SIZE (decl), stmt_p);
1175 gimplify_one_sizepos (&DECL_SIZE_UNIT (decl), stmt_p);
1176
1177 /* All occurrences of this decl in final gimplified code will be
1178 replaced by indirection. Setting DECL_VALUE_EXPR does two
1179 things: First, it lets the rest of the gimplifier know what
1180 replacement to use. Second, it lets the debug info know
1181 where to find the value. */
1182 ptr_type = build_pointer_type (TREE_TYPE (decl));
1183 addr = create_tmp_var (ptr_type, get_name (decl));
1184 DECL_IGNORED_P (addr) = 0;
1185 t = build_fold_indirect_ref (addr);
1186 SET_DECL_VALUE_EXPR (decl, t);
1187 DECL_HAS_VALUE_EXPR_P (decl) = 1;
1188
1189 args = tree_cons (NULL, DECL_SIZE_UNIT (decl), NULL);
1190 t = built_in_decls[BUILT_IN_ALLOCA];
1191 t = build_function_call_expr (t, args);
1192 t = fold_convert (ptr_type, t);
1193 t = build2 (MODIFY_EXPR, void_type_node, addr, t);
1194
1195 gimplify_and_add (t, stmt_p);
1196
1197 /* Indicate that we need to restore the stack level when the
1198 enclosing BIND_EXPR is exited. */
1199 gimplify_ctxp->save_stack = true;
1200 }
1201
1202 if (init && init != error_mark_node)
1203 {
1204 if (!TREE_STATIC (decl))
1205 {
1206 DECL_INITIAL (decl) = NULL_TREE;
1207 init = build2 (MODIFY_EXPR, void_type_node, decl, init);
1208 gimplify_and_add (init, stmt_p);
1209 }
1210 else
1211 /* We must still examine initializers for static variables
1212 as they may contain a label address. */
1213 walk_tree (&init, force_labels_r, NULL, NULL);
1214 }
1215
1216 /* This decl isn't mentioned in the enclosing block, so add it to the
1217 list of temps. FIXME it seems a bit of a kludge to say that
1218 anonymous artificial vars aren't pushed, but everything else is. */
1219 if (DECL_ARTIFICIAL (decl) && DECL_NAME (decl) == NULL_TREE)
1220 gimple_add_tmp_var (decl);
1221 }
1222
1223 return GS_ALL_DONE;
1224 }
1225
1226 /* Gimplify a LOOP_EXPR. Normally this just involves gimplifying the body
1227 and replacing the LOOP_EXPR with goto, but if the loop contains an
1228 EXIT_EXPR, we need to append a label for it to jump to. */
1229
1230 static enum gimplify_status
1231 gimplify_loop_expr (tree *expr_p, tree *pre_p)
1232 {
1233 tree saved_label = gimplify_ctxp->exit_label;
1234 tree start_label = build1 (LABEL_EXPR, void_type_node, NULL_TREE);
1235 tree jump_stmt = build_and_jump (&LABEL_EXPR_LABEL (start_label));
1236
1237 append_to_statement_list (start_label, pre_p);
1238
1239 gimplify_ctxp->exit_label = NULL_TREE;
1240
1241 gimplify_and_add (LOOP_EXPR_BODY (*expr_p), pre_p);
1242
1243 if (gimplify_ctxp->exit_label)
1244 {
1245 append_to_statement_list (jump_stmt, pre_p);
1246 *expr_p = build1 (LABEL_EXPR, void_type_node, gimplify_ctxp->exit_label);
1247 }
1248 else
1249 *expr_p = jump_stmt;
1250
1251 gimplify_ctxp->exit_label = saved_label;
1252
1253 return GS_ALL_DONE;
1254 }
1255
1256 /* Compare two case labels. Because the front end should already have
1257 made sure that case ranges do not overlap, it is enough to only compare
1258 the CASE_LOW values of each case label. */
1259
1260 static int
1261 compare_case_labels (const void *p1, const void *p2)
1262 {
1263 tree case1 = *(tree *)p1;
1264 tree case2 = *(tree *)p2;
1265
1266 return tree_int_cst_compare (CASE_LOW (case1), CASE_LOW (case2));
1267 }
1268
1269 /* Sort the case labels in LABEL_VEC in place in ascending order. */
1270
1271 void
1272 sort_case_labels (tree label_vec)
1273 {
1274 size_t len = TREE_VEC_LENGTH (label_vec);
1275 tree default_case = TREE_VEC_ELT (label_vec, len - 1);
1276
1277 if (CASE_LOW (default_case))
1278 {
1279 size_t i;
1280
1281 /* The last label in the vector should be the default case
1282 but it is not. */
1283 for (i = 0; i < len; ++i)
1284 {
1285 tree t = TREE_VEC_ELT (label_vec, i);
1286 if (!CASE_LOW (t))
1287 {
1288 default_case = t;
1289 TREE_VEC_ELT (label_vec, i) = TREE_VEC_ELT (label_vec, len - 1);
1290 TREE_VEC_ELT (label_vec, len - 1) = default_case;
1291 break;
1292 }
1293 }
1294 }
1295
1296 qsort (&TREE_VEC_ELT (label_vec, 0), len - 1, sizeof (tree),
1297 compare_case_labels);
1298 }
1299
1300 /* Gimplify a SWITCH_EXPR, and collect a TREE_VEC of the labels it can
1301 branch to. */
1302
1303 static enum gimplify_status
1304 gimplify_switch_expr (tree *expr_p, tree *pre_p)
1305 {
1306 tree switch_expr = *expr_p;
1307 enum gimplify_status ret;
1308
1309 ret = gimplify_expr (&SWITCH_COND (switch_expr), pre_p, NULL,
1310 is_gimple_val, fb_rvalue);
1311
1312 if (SWITCH_BODY (switch_expr))
1313 {
1314 VEC(tree,heap) *labels, *saved_labels;
1315 tree label_vec, default_case = NULL_TREE;
1316 size_t i, len;
1317
1318 /* If someone can be bothered to fill in the labels, they can
1319 be bothered to null out the body too. */
1320 gcc_assert (!SWITCH_LABELS (switch_expr));
1321
1322 saved_labels = gimplify_ctxp->case_labels;
1323 gimplify_ctxp->case_labels = VEC_alloc (tree, heap, 8);
1324
1325 gimplify_to_stmt_list (&SWITCH_BODY (switch_expr));
1326
1327 labels = gimplify_ctxp->case_labels;
1328 gimplify_ctxp->case_labels = saved_labels;
1329
1330 len = VEC_length (tree, labels);
1331
1332 for (i = 0; i < len; ++i)
1333 {
1334 tree t = VEC_index (tree, labels, i);
1335 if (!CASE_LOW (t))
1336 {
1337 /* The default case must be the last label in the list. */
1338 default_case = t;
1339 VEC_replace (tree, labels, i, VEC_index (tree, labels, len - 1));
1340 len--;
1341 break;
1342 }
1343 }
1344
1345 label_vec = make_tree_vec (len + 1);
1346 SWITCH_LABELS (*expr_p) = label_vec;
1347 append_to_statement_list (switch_expr, pre_p);
1348
1349 if (! default_case)
1350 {
1351 /* If the switch has no default label, add one, so that we jump
1352 around the switch body. */
1353 default_case = build3 (CASE_LABEL_EXPR, void_type_node, NULL_TREE,
1354 NULL_TREE, create_artificial_label ());
1355 append_to_statement_list (SWITCH_BODY (switch_expr), pre_p);
1356 *expr_p = build1 (LABEL_EXPR, void_type_node,
1357 CASE_LABEL (default_case));
1358 }
1359 else
1360 *expr_p = SWITCH_BODY (switch_expr);
1361
1362 for (i = 0; i < len; ++i)
1363 TREE_VEC_ELT (label_vec, i) = VEC_index (tree, labels, i);
1364 TREE_VEC_ELT (label_vec, len) = default_case;
1365
1366 VEC_free (tree, heap, labels);
1367
1368 sort_case_labels (label_vec);
1369
1370 SWITCH_BODY (switch_expr) = NULL;
1371 }
1372 else
1373 gcc_assert (SWITCH_LABELS (switch_expr));
1374
1375 return ret;
1376 }
1377
1378 static enum gimplify_status
1379 gimplify_case_label_expr (tree *expr_p)
1380 {
1381 tree expr = *expr_p;
1382 struct gimplify_ctx *ctxp;
1383
1384 /* Invalid OpenMP programs can play Duff's Device type games with
1385 #pragma omp parallel. At least in the C front end, we don't
1386 detect such invalid branches until after gimplification. */
1387 for (ctxp = gimplify_ctxp; ; ctxp = ctxp->prev_context)
1388 if (ctxp->case_labels)
1389 break;
1390
1391 VEC_safe_push (tree, heap, ctxp->case_labels, expr);
1392 *expr_p = build1 (LABEL_EXPR, void_type_node, CASE_LABEL (expr));
1393 return GS_ALL_DONE;
1394 }
1395
1396 /* Build a GOTO to the LABEL_DECL pointed to by LABEL_P, building it first
1397 if necessary. */
1398
1399 tree
1400 build_and_jump (tree *label_p)
1401 {
1402 if (label_p == NULL)
1403 /* If there's nowhere to jump, just fall through. */
1404 return NULL_TREE;
1405
1406 if (*label_p == NULL_TREE)
1407 {
1408 tree label = create_artificial_label ();
1409 *label_p = label;
1410 }
1411
1412 return build1 (GOTO_EXPR, void_type_node, *label_p);
1413 }
1414
1415 /* Gimplify an EXIT_EXPR by converting to a GOTO_EXPR inside a COND_EXPR.
1416 This also involves building a label to jump to and communicating it to
1417 gimplify_loop_expr through gimplify_ctxp->exit_label. */
1418
1419 static enum gimplify_status
1420 gimplify_exit_expr (tree *expr_p)
1421 {
1422 tree cond = TREE_OPERAND (*expr_p, 0);
1423 tree expr;
1424
1425 expr = build_and_jump (&gimplify_ctxp->exit_label);
1426 expr = build3 (COND_EXPR, void_type_node, cond, expr, NULL_TREE);
1427 *expr_p = expr;
1428
1429 return GS_OK;
1430 }
1431
1432 /* A helper function to be called via walk_tree. Mark all labels under *TP
1433 as being forced. To be called for DECL_INITIAL of static variables. */
1434
1435 tree
1436 force_labels_r (tree *tp, int *walk_subtrees, void *data ATTRIBUTE_UNUSED)
1437 {
1438 if (TYPE_P (*tp))
1439 *walk_subtrees = 0;
1440 if (TREE_CODE (*tp) == LABEL_DECL)
1441 FORCED_LABEL (*tp) = 1;
1442
1443 return NULL_TREE;
1444 }
1445
1446 /* *EXPR_P is a COMPONENT_REF being used as an rvalue. If its type is
1447 different from its canonical type, wrap the whole thing inside a
1448 NOP_EXPR and force the type of the COMPONENT_REF to be the canonical
1449 type.
1450
1451 The canonical type of a COMPONENT_REF is the type of the field being
1452 referenced--unless the field is a bit-field which can be read directly
1453 in a smaller mode, in which case the canonical type is the
1454 sign-appropriate type corresponding to that mode. */
1455
1456 static void
1457 canonicalize_component_ref (tree *expr_p)
1458 {
1459 tree expr = *expr_p;
1460 tree type;
1461
1462 gcc_assert (TREE_CODE (expr) == COMPONENT_REF);
1463
1464 if (INTEGRAL_TYPE_P (TREE_TYPE (expr)))
1465 type = TREE_TYPE (get_unwidened (expr, NULL_TREE));
1466 else
1467 type = TREE_TYPE (TREE_OPERAND (expr, 1));
1468
1469 if (TREE_TYPE (expr) != type)
1470 {
1471 tree old_type = TREE_TYPE (expr);
1472
1473 /* Set the type of the COMPONENT_REF to the underlying type. */
1474 TREE_TYPE (expr) = type;
1475
1476 /* And wrap the whole thing inside a NOP_EXPR. */
1477 expr = build1 (NOP_EXPR, old_type, expr);
1478
1479 *expr_p = expr;
1480 }
1481 }
1482
1483 /* If a NOP conversion is changing a pointer to array of foo to a pointer
1484 to foo, embed that change in the ADDR_EXPR by converting
1485 T array[U];
1486 (T *)&array
1487 ==>
1488 &array[L]
1489 where L is the lower bound. For simplicity, only do this for constant
1490 lower bound. */
1491
1492 static void
1493 canonicalize_addr_expr (tree *expr_p)
1494 {
1495 tree expr = *expr_p;
1496 tree ctype = TREE_TYPE (expr);
1497 tree addr_expr = TREE_OPERAND (expr, 0);
1498 tree atype = TREE_TYPE (addr_expr);
1499 tree dctype, datype, ddatype, otype, obj_expr;
1500
1501 /* Both cast and addr_expr types should be pointers. */
1502 if (!POINTER_TYPE_P (ctype) || !POINTER_TYPE_P (atype))
1503 return;
1504
1505 /* The addr_expr type should be a pointer to an array. */
1506 datype = TREE_TYPE (atype);
1507 if (TREE_CODE (datype) != ARRAY_TYPE)
1508 return;
1509
1510 /* Both cast and addr_expr types should address the same object type. */
1511 dctype = TREE_TYPE (ctype);
1512 ddatype = TREE_TYPE (datype);
1513 if (!lang_hooks.types_compatible_p (ddatype, dctype))
1514 return;
1515
1516 /* The addr_expr and the object type should match. */
1517 obj_expr = TREE_OPERAND (addr_expr, 0);
1518 otype = TREE_TYPE (obj_expr);
1519 if (!lang_hooks.types_compatible_p (otype, datype))
1520 return;
1521
1522 /* The lower bound and element sizes must be constant. */
1523 if (!TYPE_SIZE_UNIT (dctype)
1524 || TREE_CODE (TYPE_SIZE_UNIT (dctype)) != INTEGER_CST
1525 || !TYPE_DOMAIN (datype) || !TYPE_MIN_VALUE (TYPE_DOMAIN (datype))
1526 || TREE_CODE (TYPE_MIN_VALUE (TYPE_DOMAIN (datype))) != INTEGER_CST)
1527 return;
1528
1529 /* All checks succeeded. Build a new node to merge the cast. */
1530 *expr_p = build4 (ARRAY_REF, dctype, obj_expr,
1531 TYPE_MIN_VALUE (TYPE_DOMAIN (datype)),
1532 TYPE_MIN_VALUE (TYPE_DOMAIN (datype)),
1533 size_binop (EXACT_DIV_EXPR, TYPE_SIZE_UNIT (dctype),
1534 size_int (TYPE_ALIGN_UNIT (dctype))));
1535 *expr_p = build1 (ADDR_EXPR, ctype, *expr_p);
1536 }
1537
1538 /* *EXPR_P is a NOP_EXPR or CONVERT_EXPR. Remove it and/or other conversions
1539 underneath as appropriate. */
1540
1541 static enum gimplify_status
1542 gimplify_conversion (tree *expr_p)
1543 {
1544 gcc_assert (TREE_CODE (*expr_p) == NOP_EXPR
1545 || TREE_CODE (*expr_p) == CONVERT_EXPR);
1546
1547 /* Then strip away all but the outermost conversion. */
1548 STRIP_SIGN_NOPS (TREE_OPERAND (*expr_p, 0));
1549
1550 /* And remove the outermost conversion if it's useless. */
1551 if (tree_ssa_useless_type_conversion (*expr_p))
1552 *expr_p = TREE_OPERAND (*expr_p, 0);
1553
1554 /* If we still have a conversion at the toplevel,
1555 then canonicalize some constructs. */
1556 if (TREE_CODE (*expr_p) == NOP_EXPR || TREE_CODE (*expr_p) == CONVERT_EXPR)
1557 {
1558 tree sub = TREE_OPERAND (*expr_p, 0);
1559
1560 /* If a NOP conversion is changing the type of a COMPONENT_REF
1561 expression, then canonicalize its type now in order to expose more
1562 redundant conversions. */
1563 if (TREE_CODE (sub) == COMPONENT_REF)
1564 canonicalize_component_ref (&TREE_OPERAND (*expr_p, 0));
1565
1566 /* If a NOP conversion is changing a pointer to array of foo
1567 to a pointer to foo, embed that change in the ADDR_EXPR. */
1568 else if (TREE_CODE (sub) == ADDR_EXPR)
1569 canonicalize_addr_expr (expr_p);
1570 }
1571
1572 return GS_OK;
1573 }
1574
1575 /* Gimplify a VAR_DECL or PARM_DECL. Returns GS_OK if we expanded a
1576 DECL_VALUE_EXPR, and it's worth re-examining things. */
1577
1578 static enum gimplify_status
1579 gimplify_var_or_parm_decl (tree *expr_p)
1580 {
1581 tree decl = *expr_p;
1582
1583 /* ??? If this is a local variable, and it has not been seen in any
1584 outer BIND_EXPR, then it's probably the result of a duplicate
1585 declaration, for which we've already issued an error. It would
1586 be really nice if the front end wouldn't leak these at all.
1587 Currently the only known culprit is C++ destructors, as seen
1588 in g++.old-deja/g++.jason/binding.C. */
1589 if (TREE_CODE (decl) == VAR_DECL
1590 && !DECL_SEEN_IN_BIND_EXPR_P (decl)
1591 && !TREE_STATIC (decl) && !DECL_EXTERNAL (decl)
1592 && decl_function_context (decl) == current_function_decl)
1593 {
1594 gcc_assert (errorcount || sorrycount);
1595 return GS_ERROR;
1596 }
1597
1598 /* When within an OpenMP context, notice uses of variables. */
1599 if (gimplify_omp_ctxp && omp_notice_variable (gimplify_omp_ctxp, decl, true))
1600 return GS_ALL_DONE;
1601
1602 /* If the decl is an alias for another expression, substitute it now. */
1603 if (DECL_HAS_VALUE_EXPR_P (decl))
1604 {
1605 *expr_p = unshare_expr (DECL_VALUE_EXPR (decl));
1606 return GS_OK;
1607 }
1608
1609 return GS_ALL_DONE;
1610 }
1611
1612
1613 /* Gimplify the COMPONENT_REF, ARRAY_REF, REALPART_EXPR or IMAGPART_EXPR
1614 node pointed to by EXPR_P.
1615
1616 compound_lval
1617 : min_lval '[' val ']'
1618 | min_lval '.' ID
1619 | compound_lval '[' val ']'
1620 | compound_lval '.' ID
1621
1622 This is not part of the original SIMPLE definition, which separates
1623 array and member references, but it seems reasonable to handle them
1624 together. Also, this way we don't run into problems with union
1625 aliasing; gcc requires that for accesses through a union to alias, the
1626 union reference must be explicit, which was not always the case when we
1627 were splitting up array and member refs.
1628
1629 PRE_P points to the list where side effects that must happen before
1630 *EXPR_P should be stored.
1631
1632 POST_P points to the list where side effects that must happen after
1633 *EXPR_P should be stored. */
1634
1635 static enum gimplify_status
1636 gimplify_compound_lval (tree *expr_p, tree *pre_p,
1637 tree *post_p, fallback_t fallback)
1638 {
1639 tree *p;
1640 VEC(tree,heap) *stack;
1641 enum gimplify_status ret = GS_OK, tret;
1642 int i;
1643
1644 /* Create a stack of the subexpressions so later we can walk them in
1645 order from inner to outer. */
1646 stack = VEC_alloc (tree, heap, 10);
1647
1648 /* We can handle anything that get_inner_reference can deal with. */
1649 for (p = expr_p; ; p = &TREE_OPERAND (*p, 0))
1650 {
1651 restart:
1652 /* Fold INDIRECT_REFs now to turn them into ARRAY_REFs. */
1653 if (TREE_CODE (*p) == INDIRECT_REF)
1654 *p = fold_indirect_ref (*p);
1655
1656 if (handled_component_p (*p))
1657 ;
1658 /* Expand DECL_VALUE_EXPR now. In some cases that may expose
1659 additional COMPONENT_REFs. */
1660 else if ((TREE_CODE (*p) == VAR_DECL || TREE_CODE (*p) == PARM_DECL)
1661 && gimplify_var_or_parm_decl (p) == GS_OK)
1662 goto restart;
1663 else
1664 break;
1665
1666 VEC_safe_push (tree, heap, stack, *p);
1667 }
1668
1669 gcc_assert (VEC_length (tree, stack));
1670
1671 /* Now STACK is a stack of pointers to all the refs we've walked through
1672 and P points to the innermost expression.
1673
1674 Java requires that we elaborated nodes in source order. That
1675 means we must gimplify the inner expression followed by each of
1676 the indices, in order. But we can't gimplify the inner
1677 expression until we deal with any variable bounds, sizes, or
1678 positions in order to deal with PLACEHOLDER_EXPRs.
1679
1680 So we do this in three steps. First we deal with the annotations
1681 for any variables in the components, then we gimplify the base,
1682 then we gimplify any indices, from left to right. */
1683 for (i = VEC_length (tree, stack) - 1; i >= 0; i--)
1684 {
1685 tree t = VEC_index (tree, stack, i);
1686
1687 if (TREE_CODE (t) == ARRAY_REF || TREE_CODE (t) == ARRAY_RANGE_REF)
1688 {
1689 /* Gimplify the low bound and element type size and put them into
1690 the ARRAY_REF. If these values are set, they have already been
1691 gimplified. */
1692 if (!TREE_OPERAND (t, 2))
1693 {
1694 tree low = unshare_expr (array_ref_low_bound (t));
1695 if (!is_gimple_min_invariant (low))
1696 {
1697 TREE_OPERAND (t, 2) = low;
1698 tret = gimplify_expr (&TREE_OPERAND (t, 2), pre_p, post_p,
1699 is_gimple_formal_tmp_reg, fb_rvalue);
1700 ret = MIN (ret, tret);
1701 }
1702 }
1703
1704 if (!TREE_OPERAND (t, 3))
1705 {
1706 tree elmt_type = TREE_TYPE (TREE_TYPE (TREE_OPERAND (t, 0)));
1707 tree elmt_size = unshare_expr (array_ref_element_size (t));
1708 tree factor = size_int (TYPE_ALIGN_UNIT (elmt_type));
1709
1710 /* Divide the element size by the alignment of the element
1711 type (above). */
1712 elmt_size = size_binop (EXACT_DIV_EXPR, elmt_size, factor);
1713
1714 if (!is_gimple_min_invariant (elmt_size))
1715 {
1716 TREE_OPERAND (t, 3) = elmt_size;
1717 tret = gimplify_expr (&TREE_OPERAND (t, 3), pre_p, post_p,
1718 is_gimple_formal_tmp_reg, fb_rvalue);
1719 ret = MIN (ret, tret);
1720 }
1721 }
1722 }
1723 else if (TREE_CODE (t) == COMPONENT_REF)
1724 {
1725 /* Set the field offset into T and gimplify it. */
1726 if (!TREE_OPERAND (t, 2))
1727 {
1728 tree offset = unshare_expr (component_ref_field_offset (t));
1729 tree field = TREE_OPERAND (t, 1);
1730 tree factor
1731 = size_int (DECL_OFFSET_ALIGN (field) / BITS_PER_UNIT);
1732
1733 /* Divide the offset by its alignment. */
1734 offset = size_binop (EXACT_DIV_EXPR, offset, factor);
1735
1736 if (!is_gimple_min_invariant (offset))
1737 {
1738 TREE_OPERAND (t, 2) = offset;
1739 tret = gimplify_expr (&TREE_OPERAND (t, 2), pre_p, post_p,
1740 is_gimple_formal_tmp_reg, fb_rvalue);
1741 ret = MIN (ret, tret);
1742 }
1743 }
1744 }
1745 }
1746
1747 /* Step 2 is to gimplify the base expression. Make sure lvalue is set
1748 so as to match the min_lval predicate. Failure to do so may result
1749 in the creation of large aggregate temporaries. */
1750 tret = gimplify_expr (p, pre_p, post_p, is_gimple_min_lval,
1751 fallback | fb_lvalue);
1752 ret = MIN (ret, tret);
1753
1754 /* And finally, the indices and operands to BIT_FIELD_REF. During this
1755 loop we also remove any useless conversions. */
1756 for (; VEC_length (tree, stack) > 0; )
1757 {
1758 tree t = VEC_pop (tree, stack);
1759
1760 if (TREE_CODE (t) == ARRAY_REF || TREE_CODE (t) == ARRAY_RANGE_REF)
1761 {
1762 /* Gimplify the dimension.
1763 Temporary fix for gcc.c-torture/execute/20040313-1.c.
1764 Gimplify non-constant array indices into a temporary
1765 variable.
1766 FIXME - The real fix is to gimplify post-modify
1767 expressions into a minimal gimple lvalue. However, that
1768 exposes bugs in alias analysis. The alias analyzer does
1769 not handle &PTR->FIELD very well. Will fix after the
1770 branch is merged into mainline (dnovillo 2004-05-03). */
1771 if (!is_gimple_min_invariant (TREE_OPERAND (t, 1)))
1772 {
1773 tret = gimplify_expr (&TREE_OPERAND (t, 1), pre_p, post_p,
1774 is_gimple_formal_tmp_reg, fb_rvalue);
1775 ret = MIN (ret, tret);
1776 }
1777 }
1778 else if (TREE_CODE (t) == BIT_FIELD_REF)
1779 {
1780 tret = gimplify_expr (&TREE_OPERAND (t, 1), pre_p, post_p,
1781 is_gimple_val, fb_rvalue);
1782 ret = MIN (ret, tret);
1783 tret = gimplify_expr (&TREE_OPERAND (t, 2), pre_p, post_p,
1784 is_gimple_val, fb_rvalue);
1785 ret = MIN (ret, tret);
1786 }
1787
1788 STRIP_USELESS_TYPE_CONVERSION (TREE_OPERAND (t, 0));
1789
1790 /* The innermost expression P may have originally had TREE_SIDE_EFFECTS
1791 set which would have caused all the outer expressions in EXPR_P
1792 leading to P to also have had TREE_SIDE_EFFECTS set. */
1793 recalculate_side_effects (t);
1794 }
1795
1796 tret = gimplify_expr (p, pre_p, post_p, is_gimple_min_lval, fallback);
1797 ret = MIN (ret, tret);
1798
1799 /* If the outermost expression is a COMPONENT_REF, canonicalize its type. */
1800 if ((fallback & fb_rvalue) && TREE_CODE (*expr_p) == COMPONENT_REF)
1801 {
1802 canonicalize_component_ref (expr_p);
1803 ret = MIN (ret, GS_OK);
1804 }
1805
1806 VEC_free (tree, heap, stack);
1807
1808 return ret;
1809 }
1810
1811 /* Gimplify the self modifying expression pointed to by EXPR_P
1812 (++, --, +=, -=).
1813
1814 PRE_P points to the list where side effects that must happen before
1815 *EXPR_P should be stored.
1816
1817 POST_P points to the list where side effects that must happen after
1818 *EXPR_P should be stored.
1819
1820 WANT_VALUE is nonzero iff we want to use the value of this expression
1821 in another expression. */
1822
1823 static enum gimplify_status
1824 gimplify_self_mod_expr (tree *expr_p, tree *pre_p, tree *post_p,
1825 bool want_value)
1826 {
1827 enum tree_code code;
1828 tree lhs, lvalue, rhs, t1;
1829 bool postfix;
1830 enum tree_code arith_code;
1831 enum gimplify_status ret;
1832
1833 code = TREE_CODE (*expr_p);
1834
1835 gcc_assert (code == POSTINCREMENT_EXPR || code == POSTDECREMENT_EXPR
1836 || code == PREINCREMENT_EXPR || code == PREDECREMENT_EXPR);
1837
1838 /* Prefix or postfix? */
1839 if (code == POSTINCREMENT_EXPR || code == POSTDECREMENT_EXPR)
1840 /* Faster to treat as prefix if result is not used. */
1841 postfix = want_value;
1842 else
1843 postfix = false;
1844
1845 /* Add or subtract? */
1846 if (code == PREINCREMENT_EXPR || code == POSTINCREMENT_EXPR)
1847 arith_code = PLUS_EXPR;
1848 else
1849 arith_code = MINUS_EXPR;
1850
1851 /* Gimplify the LHS into a GIMPLE lvalue. */
1852 lvalue = TREE_OPERAND (*expr_p, 0);
1853 ret = gimplify_expr (&lvalue, pre_p, post_p, is_gimple_lvalue, fb_lvalue);
1854 if (ret == GS_ERROR)
1855 return ret;
1856
1857 /* Extract the operands to the arithmetic operation. */
1858 lhs = lvalue;
1859 rhs = TREE_OPERAND (*expr_p, 1);
1860
1861 /* For postfix operator, we evaluate the LHS to an rvalue and then use
1862 that as the result value and in the postqueue operation. */
1863 if (postfix)
1864 {
1865 ret = gimplify_expr (&lhs, pre_p, post_p, is_gimple_val, fb_rvalue);
1866 if (ret == GS_ERROR)
1867 return ret;
1868 }
1869
1870 t1 = build2 (arith_code, TREE_TYPE (*expr_p), lhs, rhs);
1871 t1 = build2 (MODIFY_EXPR, TREE_TYPE (lvalue), lvalue, t1);
1872
1873 if (postfix)
1874 {
1875 gimplify_and_add (t1, post_p);
1876 *expr_p = lhs;
1877 return GS_ALL_DONE;
1878 }
1879 else
1880 {
1881 *expr_p = t1;
1882 return GS_OK;
1883 }
1884 }
1885
1886 /* If *EXPR_P has a variable sized type, wrap it in a WITH_SIZE_EXPR. */
1887
1888 static void
1889 maybe_with_size_expr (tree *expr_p)
1890 {
1891 tree expr = *expr_p;
1892 tree type = TREE_TYPE (expr);
1893 tree size;
1894
1895 /* If we've already wrapped this or the type is error_mark_node, we can't do
1896 anything. */
1897 if (TREE_CODE (expr) == WITH_SIZE_EXPR
1898 || type == error_mark_node)
1899 return;
1900
1901 /* If the size isn't known or is a constant, we have nothing to do. */
1902 size = TYPE_SIZE_UNIT (type);
1903 if (!size || TREE_CODE (size) == INTEGER_CST)
1904 return;
1905
1906 /* Otherwise, make a WITH_SIZE_EXPR. */
1907 size = unshare_expr (size);
1908 size = SUBSTITUTE_PLACEHOLDER_IN_EXPR (size, expr);
1909 *expr_p = build2 (WITH_SIZE_EXPR, type, expr, size);
1910 }
1911
1912 /* Subroutine of gimplify_call_expr: Gimplify a single argument. */
1913
1914 static enum gimplify_status
1915 gimplify_arg (tree *expr_p, tree *pre_p)
1916 {
1917 bool (*test) (tree);
1918 fallback_t fb;
1919
1920 /* In general, we allow lvalues for function arguments to avoid
1921 extra overhead of copying large aggregates out of even larger
1922 aggregates into temporaries only to copy the temporaries to
1923 the argument list. Make optimizers happy by pulling out to
1924 temporaries those types that fit in registers. */
1925 if (is_gimple_reg_type (TREE_TYPE (*expr_p)))
1926 test = is_gimple_val, fb = fb_rvalue;
1927 else
1928 test = is_gimple_lvalue, fb = fb_either;
1929
1930 /* If this is a variable sized type, we must remember the size. */
1931 maybe_with_size_expr (expr_p);
1932
1933 /* There is a sequence point before a function call. Side effects in
1934 the argument list must occur before the actual call. So, when
1935 gimplifying arguments, force gimplify_expr to use an internal
1936 post queue which is then appended to the end of PRE_P. */
1937 return gimplify_expr (expr_p, pre_p, NULL, test, fb);
1938 }
1939
1940 /* Gimplify the CALL_EXPR node pointed to by EXPR_P. PRE_P points to the
1941 list where side effects that must happen before *EXPR_P should be stored.
1942 WANT_VALUE is true if the result of the call is desired. */
1943
1944 static enum gimplify_status
1945 gimplify_call_expr (tree *expr_p, tree *pre_p, bool want_value)
1946 {
1947 tree decl;
1948 tree arglist;
1949 enum gimplify_status ret;
1950
1951 gcc_assert (TREE_CODE (*expr_p) == CALL_EXPR);
1952
1953 /* For reliable diagnostics during inlining, it is necessary that
1954 every call_expr be annotated with file and line. */
1955 if (! EXPR_HAS_LOCATION (*expr_p))
1956 SET_EXPR_LOCATION (*expr_p, input_location);
1957
1958 /* This may be a call to a builtin function.
1959
1960 Builtin function calls may be transformed into different
1961 (and more efficient) builtin function calls under certain
1962 circumstances. Unfortunately, gimplification can muck things
1963 up enough that the builtin expanders are not aware that certain
1964 transformations are still valid.
1965
1966 So we attempt transformation/gimplification of the call before
1967 we gimplify the CALL_EXPR. At this time we do not manage to
1968 transform all calls in the same manner as the expanders do, but
1969 we do transform most of them. */
1970 decl = get_callee_fndecl (*expr_p);
1971 if (decl && DECL_BUILT_IN (decl))
1972 {
1973 tree fndecl = get_callee_fndecl (*expr_p);
1974 tree arglist = TREE_OPERAND (*expr_p, 1);
1975 tree new = fold_builtin (fndecl, arglist, !want_value);
1976
1977 if (new && new != *expr_p)
1978 {
1979 /* There was a transformation of this call which computes the
1980 same value, but in a more efficient way. Return and try
1981 again. */
1982 *expr_p = new;
1983 return GS_OK;
1984 }
1985
1986 if (DECL_BUILT_IN_CLASS (decl) == BUILT_IN_NORMAL
1987 && DECL_FUNCTION_CODE (decl) == BUILT_IN_VA_START)
1988 {
1989 if (!arglist || !TREE_CHAIN (arglist))
1990 {
1991 error ("too few arguments to function %<va_start%>");
1992 *expr_p = build_empty_stmt ();
1993 return GS_OK;
1994 }
1995
1996 if (fold_builtin_next_arg (TREE_CHAIN (arglist)))
1997 {
1998 *expr_p = build_empty_stmt ();
1999 return GS_OK;
2000 }
2001 /* Avoid gimplifying the second argument to va_start, which needs
2002 to be the plain PARM_DECL. */
2003 return gimplify_arg (&TREE_VALUE (TREE_OPERAND (*expr_p, 1)), pre_p);
2004 }
2005 }
2006
2007 /* There is a sequence point before the call, so any side effects in
2008 the calling expression must occur before the actual call. Force
2009 gimplify_expr to use an internal post queue. */
2010 ret = gimplify_expr (&TREE_OPERAND (*expr_p, 0), pre_p, NULL,
2011 is_gimple_call_addr, fb_rvalue);
2012
2013 if (PUSH_ARGS_REVERSED)
2014 TREE_OPERAND (*expr_p, 1) = nreverse (TREE_OPERAND (*expr_p, 1));
2015 for (arglist = TREE_OPERAND (*expr_p, 1); arglist;
2016 arglist = TREE_CHAIN (arglist))
2017 {
2018 enum gimplify_status t;
2019
2020 t = gimplify_arg (&TREE_VALUE (arglist), pre_p);
2021
2022 if (t == GS_ERROR)
2023 ret = GS_ERROR;
2024 }
2025 if (PUSH_ARGS_REVERSED)
2026 TREE_OPERAND (*expr_p, 1) = nreverse (TREE_OPERAND (*expr_p, 1));
2027
2028 /* Try this again in case gimplification exposed something. */
2029 if (ret != GS_ERROR && decl && DECL_BUILT_IN (decl))
2030 {
2031 tree fndecl = get_callee_fndecl (*expr_p);
2032 tree arglist = TREE_OPERAND (*expr_p, 1);
2033 tree new = fold_builtin (fndecl, arglist, !want_value);
2034
2035 if (new && new != *expr_p)
2036 {
2037 /* There was a transformation of this call which computes the
2038 same value, but in a more efficient way. Return and try
2039 again. */
2040 *expr_p = new;
2041 return GS_OK;
2042 }
2043 }
2044
2045 /* If the function is "const" or "pure", then clear TREE_SIDE_EFFECTS on its
2046 decl. This allows us to eliminate redundant or useless
2047 calls to "const" functions. */
2048 if (TREE_CODE (*expr_p) == CALL_EXPR
2049 && (call_expr_flags (*expr_p) & (ECF_CONST | ECF_PURE)))
2050 TREE_SIDE_EFFECTS (*expr_p) = 0;
2051
2052 return ret;
2053 }
2054
2055 /* Handle shortcut semantics in the predicate operand of a COND_EXPR by
2056 rewriting it into multiple COND_EXPRs, and possibly GOTO_EXPRs.
2057
2058 TRUE_LABEL_P and FALSE_LABEL_P point to the labels to jump to if the
2059 condition is true or false, respectively. If null, we should generate
2060 our own to skip over the evaluation of this specific expression.
2061
2062 This function is the tree equivalent of do_jump.
2063
2064 shortcut_cond_r should only be called by shortcut_cond_expr. */
2065
2066 static tree
2067 shortcut_cond_r (tree pred, tree *true_label_p, tree *false_label_p)
2068 {
2069 tree local_label = NULL_TREE;
2070 tree t, expr = NULL;
2071
2072 /* OK, it's not a simple case; we need to pull apart the COND_EXPR to
2073 retain the shortcut semantics. Just insert the gotos here;
2074 shortcut_cond_expr will append the real blocks later. */
2075 if (TREE_CODE (pred) == TRUTH_ANDIF_EXPR)
2076 {
2077 /* Turn if (a && b) into
2078
2079 if (a); else goto no;
2080 if (b) goto yes; else goto no;
2081 (no:) */
2082
2083 if (false_label_p == NULL)
2084 false_label_p = &local_label;
2085
2086 t = shortcut_cond_r (TREE_OPERAND (pred, 0), NULL, false_label_p);
2087 append_to_statement_list (t, &expr);
2088
2089 t = shortcut_cond_r (TREE_OPERAND (pred, 1), true_label_p,
2090 false_label_p);
2091 append_to_statement_list (t, &expr);
2092 }
2093 else if (TREE_CODE (pred) == TRUTH_ORIF_EXPR)
2094 {
2095 /* Turn if (a || b) into
2096
2097 if (a) goto yes;
2098 if (b) goto yes; else goto no;
2099 (yes:) */
2100
2101 if (true_label_p == NULL)
2102 true_label_p = &local_label;
2103
2104 t = shortcut_cond_r (TREE_OPERAND (pred, 0), true_label_p, NULL);
2105 append_to_statement_list (t, &expr);
2106
2107 t = shortcut_cond_r (TREE_OPERAND (pred, 1), true_label_p,
2108 false_label_p);
2109 append_to_statement_list (t, &expr);
2110 }
2111 else if (TREE_CODE (pred) == COND_EXPR)
2112 {
2113 /* As long as we're messing with gotos, turn if (a ? b : c) into
2114 if (a)
2115 if (b) goto yes; else goto no;
2116 else
2117 if (c) goto yes; else goto no; */
2118 expr = build3 (COND_EXPR, void_type_node, TREE_OPERAND (pred, 0),
2119 shortcut_cond_r (TREE_OPERAND (pred, 1), true_label_p,
2120 false_label_p),
2121 shortcut_cond_r (TREE_OPERAND (pred, 2), true_label_p,
2122 false_label_p));
2123 }
2124 else
2125 {
2126 expr = build3 (COND_EXPR, void_type_node, pred,
2127 build_and_jump (true_label_p),
2128 build_and_jump (false_label_p));
2129 }
2130
2131 if (local_label)
2132 {
2133 t = build1 (LABEL_EXPR, void_type_node, local_label);
2134 append_to_statement_list (t, &expr);
2135 }
2136
2137 return expr;
2138 }
2139
2140 static tree
2141 shortcut_cond_expr (tree expr)
2142 {
2143 tree pred = TREE_OPERAND (expr, 0);
2144 tree then_ = TREE_OPERAND (expr, 1);
2145 tree else_ = TREE_OPERAND (expr, 2);
2146 tree true_label, false_label, end_label, t;
2147 tree *true_label_p;
2148 tree *false_label_p;
2149 bool emit_end, emit_false, jump_over_else;
2150 bool then_se = then_ && TREE_SIDE_EFFECTS (then_);
2151 bool else_se = else_ && TREE_SIDE_EFFECTS (else_);
2152
2153 /* First do simple transformations. */
2154 if (!else_se)
2155 {
2156 /* If there is no 'else', turn (a && b) into if (a) if (b). */
2157 while (TREE_CODE (pred) == TRUTH_ANDIF_EXPR)
2158 {
2159 TREE_OPERAND (expr, 0) = TREE_OPERAND (pred, 1);
2160 then_ = shortcut_cond_expr (expr);
2161 then_se = then_ && TREE_SIDE_EFFECTS (then_);
2162 pred = TREE_OPERAND (pred, 0);
2163 expr = build3 (COND_EXPR, void_type_node, pred, then_, NULL_TREE);
2164 }
2165 }
2166 if (!then_se)
2167 {
2168 /* If there is no 'then', turn
2169 if (a || b); else d
2170 into
2171 if (a); else if (b); else d. */
2172 while (TREE_CODE (pred) == TRUTH_ORIF_EXPR)
2173 {
2174 TREE_OPERAND (expr, 0) = TREE_OPERAND (pred, 1);
2175 else_ = shortcut_cond_expr (expr);
2176 else_se = else_ && TREE_SIDE_EFFECTS (else_);
2177 pred = TREE_OPERAND (pred, 0);
2178 expr = build3 (COND_EXPR, void_type_node, pred, NULL_TREE, else_);
2179 }
2180 }
2181
2182 /* If we're done, great. */
2183 if (TREE_CODE (pred) != TRUTH_ANDIF_EXPR
2184 && TREE_CODE (pred) != TRUTH_ORIF_EXPR)
2185 return expr;
2186
2187 /* Otherwise we need to mess with gotos. Change
2188 if (a) c; else d;
2189 to
2190 if (a); else goto no;
2191 c; goto end;
2192 no: d; end:
2193 and recursively gimplify the condition. */
2194
2195 true_label = false_label = end_label = NULL_TREE;
2196
2197 /* If our arms just jump somewhere, hijack those labels so we don't
2198 generate jumps to jumps. */
2199
2200 if (then_
2201 && TREE_CODE (then_) == GOTO_EXPR
2202 && TREE_CODE (GOTO_DESTINATION (then_)) == LABEL_DECL)
2203 {
2204 true_label = GOTO_DESTINATION (then_);
2205 then_ = NULL;
2206 then_se = false;
2207 }
2208
2209 if (else_
2210 && TREE_CODE (else_) == GOTO_EXPR
2211 && TREE_CODE (GOTO_DESTINATION (else_)) == LABEL_DECL)
2212 {
2213 false_label = GOTO_DESTINATION (else_);
2214 else_ = NULL;
2215 else_se = false;
2216 }
2217
2218 /* If we aren't hijacking a label for the 'then' branch, it falls through. */
2219 if (true_label)
2220 true_label_p = &true_label;
2221 else
2222 true_label_p = NULL;
2223
2224 /* The 'else' branch also needs a label if it contains interesting code. */
2225 if (false_label || else_se)
2226 false_label_p = &false_label;
2227 else
2228 false_label_p = NULL;
2229
2230 /* If there was nothing else in our arms, just forward the label(s). */
2231 if (!then_se && !else_se)
2232 return shortcut_cond_r (pred, true_label_p, false_label_p);
2233
2234 /* If our last subexpression already has a terminal label, reuse it. */
2235 if (else_se)
2236 expr = expr_last (else_);
2237 else if (then_se)
2238 expr = expr_last (then_);
2239 else
2240 expr = NULL;
2241 if (expr && TREE_CODE (expr) == LABEL_EXPR)
2242 end_label = LABEL_EXPR_LABEL (expr);
2243
2244 /* If we don't care about jumping to the 'else' branch, jump to the end
2245 if the condition is false. */
2246 if (!false_label_p)
2247 false_label_p = &end_label;
2248
2249 /* We only want to emit these labels if we aren't hijacking them. */
2250 emit_end = (end_label == NULL_TREE);
2251 emit_false = (false_label == NULL_TREE);
2252
2253 /* We only emit the jump over the else clause if we have to--if the
2254 then clause may fall through. Otherwise we can wind up with a
2255 useless jump and a useless label at the end of gimplified code,
2256 which will cause us to think that this conditional as a whole
2257 falls through even if it doesn't. If we then inline a function
2258 which ends with such a condition, that can cause us to issue an
2259 inappropriate warning about control reaching the end of a
2260 non-void function. */
2261 jump_over_else = block_may_fallthru (then_);
2262
2263 pred = shortcut_cond_r (pred, true_label_p, false_label_p);
2264
2265 expr = NULL;
2266 append_to_statement_list (pred, &expr);
2267
2268 append_to_statement_list (then_, &expr);
2269 if (else_se)
2270 {
2271 if (jump_over_else)
2272 {
2273 t = build_and_jump (&end_label);
2274 append_to_statement_list (t, &expr);
2275 }
2276 if (emit_false)
2277 {
2278 t = build1 (LABEL_EXPR, void_type_node, false_label);
2279 append_to_statement_list (t, &expr);
2280 }
2281 append_to_statement_list (else_, &expr);
2282 }
2283 if (emit_end && end_label)
2284 {
2285 t = build1 (LABEL_EXPR, void_type_node, end_label);
2286 append_to_statement_list (t, &expr);
2287 }
2288
2289 return expr;
2290 }
2291
2292 /* EXPR is used in a boolean context; make sure it has BOOLEAN_TYPE. */
2293
2294 tree
2295 gimple_boolify (tree expr)
2296 {
2297 tree type = TREE_TYPE (expr);
2298
2299 if (TREE_CODE (type) == BOOLEAN_TYPE)
2300 return expr;
2301
2302 switch (TREE_CODE (expr))
2303 {
2304 case TRUTH_AND_EXPR:
2305 case TRUTH_OR_EXPR:
2306 case TRUTH_XOR_EXPR:
2307 case TRUTH_ANDIF_EXPR:
2308 case TRUTH_ORIF_EXPR:
2309 /* Also boolify the arguments of truth exprs. */
2310 TREE_OPERAND (expr, 1) = gimple_boolify (TREE_OPERAND (expr, 1));
2311 /* FALLTHRU */
2312
2313 case TRUTH_NOT_EXPR:
2314 TREE_OPERAND (expr, 0) = gimple_boolify (TREE_OPERAND (expr, 0));
2315 /* FALLTHRU */
2316
2317 case EQ_EXPR: case NE_EXPR:
2318 case LE_EXPR: case GE_EXPR: case LT_EXPR: case GT_EXPR:
2319 /* These expressions always produce boolean results. */
2320 TREE_TYPE (expr) = boolean_type_node;
2321 return expr;
2322
2323 default:
2324 /* Other expressions that get here must have boolean values, but
2325 might need to be converted to the appropriate mode. */
2326 return convert (boolean_type_node, expr);
2327 }
2328 }
2329
2330 /* Convert the conditional expression pointed to by EXPR_P '(p) ? a : b;'
2331 into
2332
2333 if (p) if (p)
2334 t1 = a; a;
2335 else or else
2336 t1 = b; b;
2337 t1;
2338
2339 The second form is used when *EXPR_P is of type void.
2340
2341 TARGET is the tree for T1 above.
2342
2343 PRE_P points to the list where side effects that must happen before
2344 *EXPR_P should be stored.
2345
2346 POST_P points to the list where side effects that must happen after
2347 *EXPR_P should be stored. */
2348
2349 static enum gimplify_status
2350 gimplify_cond_expr (tree *expr_p, tree *pre_p, tree *post_p, tree target,
2351 fallback_t fallback)
2352 {
2353 tree expr = *expr_p;
2354 tree tmp, tmp2, type;
2355 enum gimplify_status ret;
2356
2357 type = TREE_TYPE (expr);
2358
2359 /* If this COND_EXPR has a value, copy the values into a temporary within
2360 the arms. */
2361 if (! VOID_TYPE_P (type))
2362 {
2363 tree result;
2364
2365 if (target)
2366 {
2367 ret = gimplify_expr (&target, pre_p, post_p,
2368 is_gimple_min_lval, fb_lvalue);
2369 if (ret != GS_ERROR)
2370 ret = GS_OK;
2371 result = tmp = target;
2372 tmp2 = unshare_expr (target);
2373 }
2374 else if ((fallback & fb_lvalue) == 0)
2375 {
2376 result = tmp2 = tmp = create_tmp_var (TREE_TYPE (expr), "iftmp");
2377 ret = GS_ALL_DONE;
2378 }
2379 else
2380 {
2381 tree type = build_pointer_type (TREE_TYPE (expr));
2382
2383 if (TREE_TYPE (TREE_OPERAND (expr, 1)) != void_type_node)
2384 TREE_OPERAND (expr, 1) =
2385 build_fold_addr_expr (TREE_OPERAND (expr, 1));
2386
2387 if (TREE_TYPE (TREE_OPERAND (expr, 2)) != void_type_node)
2388 TREE_OPERAND (expr, 2) =
2389 build_fold_addr_expr (TREE_OPERAND (expr, 2));
2390
2391 tmp2 = tmp = create_tmp_var (type, "iftmp");
2392
2393 expr = build3 (COND_EXPR, void_type_node, TREE_OPERAND (expr, 0),
2394 TREE_OPERAND (expr, 1), TREE_OPERAND (expr, 2));
2395
2396 result = build_fold_indirect_ref (tmp);
2397 ret = GS_ALL_DONE;
2398 }
2399
2400 /* Build the then clause, 't1 = a;'. But don't build an assignment
2401 if this branch is void; in C++ it can be, if it's a throw. */
2402 if (TREE_TYPE (TREE_OPERAND (expr, 1)) != void_type_node)
2403 TREE_OPERAND (expr, 1)
2404 = build2 (MODIFY_EXPR, void_type_node, tmp, TREE_OPERAND (expr, 1));
2405
2406 /* Build the else clause, 't1 = b;'. */
2407 if (TREE_TYPE (TREE_OPERAND (expr, 2)) != void_type_node)
2408 TREE_OPERAND (expr, 2)
2409 = build2 (MODIFY_EXPR, void_type_node, tmp2, TREE_OPERAND (expr, 2));
2410
2411 TREE_TYPE (expr) = void_type_node;
2412 recalculate_side_effects (expr);
2413
2414 /* Move the COND_EXPR to the prequeue. */
2415 gimplify_and_add (expr, pre_p);
2416
2417 *expr_p = result;
2418 return ret;
2419 }
2420
2421 /* Make sure the condition has BOOLEAN_TYPE. */
2422 TREE_OPERAND (expr, 0) = gimple_boolify (TREE_OPERAND (expr, 0));
2423
2424 /* Break apart && and || conditions. */
2425 if (TREE_CODE (TREE_OPERAND (expr, 0)) == TRUTH_ANDIF_EXPR
2426 || TREE_CODE (TREE_OPERAND (expr, 0)) == TRUTH_ORIF_EXPR)
2427 {
2428 expr = shortcut_cond_expr (expr);
2429
2430 if (expr != *expr_p)
2431 {
2432 *expr_p = expr;
2433
2434 /* We can't rely on gimplify_expr to re-gimplify the expanded
2435 form properly, as cleanups might cause the target labels to be
2436 wrapped in a TRY_FINALLY_EXPR. To prevent that, we need to
2437 set up a conditional context. */
2438 gimple_push_condition ();
2439 gimplify_stmt (expr_p);
2440 gimple_pop_condition (pre_p);
2441
2442 return GS_ALL_DONE;
2443 }
2444 }
2445
2446 /* Now do the normal gimplification. */
2447 ret = gimplify_expr (&TREE_OPERAND (expr, 0), pre_p, NULL,
2448 is_gimple_condexpr, fb_rvalue);
2449
2450 gimple_push_condition ();
2451
2452 gimplify_to_stmt_list (&TREE_OPERAND (expr, 1));
2453 gimplify_to_stmt_list (&TREE_OPERAND (expr, 2));
2454 recalculate_side_effects (expr);
2455
2456 gimple_pop_condition (pre_p);
2457
2458 if (ret == GS_ERROR)
2459 ;
2460 else if (TREE_SIDE_EFFECTS (TREE_OPERAND (expr, 1)))
2461 ret = GS_ALL_DONE;
2462 else if (TREE_SIDE_EFFECTS (TREE_OPERAND (expr, 2)))
2463 /* Rewrite "if (a); else b" to "if (!a) b" */
2464 {
2465 TREE_OPERAND (expr, 0) = invert_truthvalue (TREE_OPERAND (expr, 0));
2466 ret = gimplify_expr (&TREE_OPERAND (expr, 0), pre_p, NULL,
2467 is_gimple_condexpr, fb_rvalue);
2468
2469 tmp = TREE_OPERAND (expr, 1);
2470 TREE_OPERAND (expr, 1) = TREE_OPERAND (expr, 2);
2471 TREE_OPERAND (expr, 2) = tmp;
2472 }
2473 else
2474 /* Both arms are empty; replace the COND_EXPR with its predicate. */
2475 expr = TREE_OPERAND (expr, 0);
2476
2477 *expr_p = expr;
2478 return ret;
2479 }
2480
2481 /* A subroutine of gimplify_modify_expr. Replace a MODIFY_EXPR with
2482 a call to __builtin_memcpy. */
2483
2484 static enum gimplify_status
2485 gimplify_modify_expr_to_memcpy (tree *expr_p, tree size, bool want_value)
2486 {
2487 tree args, t, to, to_ptr, from;
2488
2489 to = TREE_OPERAND (*expr_p, 0);
2490 from = TREE_OPERAND (*expr_p, 1);
2491
2492 args = tree_cons (NULL, size, NULL);
2493
2494 t = build_fold_addr_expr (from);
2495 args = tree_cons (NULL, t, args);
2496
2497 to_ptr = build_fold_addr_expr (to);
2498 args = tree_cons (NULL, to_ptr, args);
2499 t = implicit_built_in_decls[BUILT_IN_MEMCPY];
2500 t = build_function_call_expr (t, args);
2501
2502 if (want_value)
2503 {
2504 t = build1 (NOP_EXPR, TREE_TYPE (to_ptr), t);
2505 t = build1 (INDIRECT_REF, TREE_TYPE (to), t);
2506 }
2507
2508 *expr_p = t;
2509 return GS_OK;
2510 }
2511
2512 /* A subroutine of gimplify_modify_expr. Replace a MODIFY_EXPR with
2513 a call to __builtin_memset. In this case we know that the RHS is
2514 a CONSTRUCTOR with an empty element list. */
2515
2516 static enum gimplify_status
2517 gimplify_modify_expr_to_memset (tree *expr_p, tree size, bool want_value)
2518 {
2519 tree args, t, to, to_ptr;
2520
2521 to = TREE_OPERAND (*expr_p, 0);
2522
2523 args = tree_cons (NULL, size, NULL);
2524
2525 args = tree_cons (NULL, integer_zero_node, args);
2526
2527 to_ptr = build_fold_addr_expr (to);
2528 args = tree_cons (NULL, to_ptr, args);
2529 t = implicit_built_in_decls[BUILT_IN_MEMSET];
2530 t = build_function_call_expr (t, args);
2531
2532 if (want_value)
2533 {
2534 t = build1 (NOP_EXPR, TREE_TYPE (to_ptr), t);
2535 t = build1 (INDIRECT_REF, TREE_TYPE (to), t);
2536 }
2537
2538 *expr_p = t;
2539 return GS_OK;
2540 }
2541
2542 /* A subroutine of gimplify_init_ctor_preeval. Called via walk_tree,
2543 determine, cautiously, if a CONSTRUCTOR overlaps the lhs of an
2544 assignment. Returns non-null if we detect a potential overlap. */
2545
2546 struct gimplify_init_ctor_preeval_data
2547 {
2548 /* The base decl of the lhs object. May be NULL, in which case we
2549 have to assume the lhs is indirect. */
2550 tree lhs_base_decl;
2551
2552 /* The alias set of the lhs object. */
2553 int lhs_alias_set;
2554 };
2555
2556 static tree
2557 gimplify_init_ctor_preeval_1 (tree *tp, int *walk_subtrees, void *xdata)
2558 {
2559 struct gimplify_init_ctor_preeval_data *data
2560 = (struct gimplify_init_ctor_preeval_data *) xdata;
2561 tree t = *tp;
2562
2563 /* If we find the base object, obviously we have overlap. */
2564 if (data->lhs_base_decl == t)
2565 return t;
2566
2567 /* If the constructor component is indirect, determine if we have a
2568 potential overlap with the lhs. The only bits of information we
2569 have to go on at this point are addressability and alias sets. */
2570 if (TREE_CODE (t) == INDIRECT_REF
2571 && (!data->lhs_base_decl || TREE_ADDRESSABLE (data->lhs_base_decl))
2572 && alias_sets_conflict_p (data->lhs_alias_set, get_alias_set (t)))
2573 return t;
2574
2575 if (IS_TYPE_OR_DECL_P (t))
2576 *walk_subtrees = 0;
2577 return NULL;
2578 }
2579
2580 /* A subroutine of gimplify_init_constructor. Pre-evaluate *EXPR_P,
2581 force values that overlap with the lhs (as described by *DATA)
2582 into temporaries. */
2583
2584 static void
2585 gimplify_init_ctor_preeval (tree *expr_p, tree *pre_p, tree *post_p,
2586 struct gimplify_init_ctor_preeval_data *data)
2587 {
2588 enum gimplify_status one;
2589
2590 /* If the value is invariant, then there's nothing to pre-evaluate.
2591 But ensure it doesn't have any side-effects since a SAVE_EXPR is
2592 invariant but has side effects and might contain a reference to
2593 the object we're initializing. */
2594 if (TREE_INVARIANT (*expr_p) && !TREE_SIDE_EFFECTS (*expr_p))
2595 return;
2596
2597 /* If the type has non-trivial constructors, we can't pre-evaluate. */
2598 if (TREE_ADDRESSABLE (TREE_TYPE (*expr_p)))
2599 return;
2600
2601 /* Recurse for nested constructors. */
2602 if (TREE_CODE (*expr_p) == CONSTRUCTOR)
2603 {
2604 unsigned HOST_WIDE_INT ix;
2605 constructor_elt *ce;
2606 VEC(constructor_elt,gc) *v = CONSTRUCTOR_ELTS (*expr_p);
2607
2608 for (ix = 0; VEC_iterate (constructor_elt, v, ix, ce); ix++)
2609 gimplify_init_ctor_preeval (&ce->value, pre_p, post_p, data);
2610 return;
2611 }
2612
2613 /* We can't preevaluate if the type contains a placeholder. */
2614 if (type_contains_placeholder_p (TREE_TYPE (*expr_p)))
2615 return;
2616
2617 /* Gimplify the constructor element to something appropriate for the rhs
2618 of a MODIFY_EXPR. Given that we know the lhs is an aggregate, we know
2619 the gimplifier will consider this a store to memory. Doing this
2620 gimplification now means that we won't have to deal with complicated
2621 language-specific trees, nor trees like SAVE_EXPR that can induce
2622 exponential search behavior. */
2623 one = gimplify_expr (expr_p, pre_p, post_p, is_gimple_mem_rhs, fb_rvalue);
2624 if (one == GS_ERROR)
2625 {
2626 *expr_p = NULL;
2627 return;
2628 }
2629
2630 /* If we gimplified to a bare decl, we can be sure that it doesn't overlap
2631 with the lhs, since "a = { .x=a }" doesn't make sense. This will
2632 always be true for all scalars, since is_gimple_mem_rhs insists on a
2633 temporary variable for them. */
2634 if (DECL_P (*expr_p))
2635 return;
2636
2637 /* If this is of variable size, we have no choice but to assume it doesn't
2638 overlap since we can't make a temporary for it. */
2639 if (!TREE_CONSTANT (TYPE_SIZE (TREE_TYPE (*expr_p))))
2640 return;
2641
2642 /* Otherwise, we must search for overlap ... */
2643 if (!walk_tree (expr_p, gimplify_init_ctor_preeval_1, data, NULL))
2644 return;
2645
2646 /* ... and if found, force the value into a temporary. */
2647 *expr_p = get_formal_tmp_var (*expr_p, pre_p);
2648 }
2649
2650 /* A subroutine of gimplify_init_ctor_eval. Create a loop for
2651 a RANGE_EXPR in a CONSTRUCTOR for an array.
2652
2653 var = lower;
2654 loop_entry:
2655 object[var] = value;
2656 if (var == upper)
2657 goto loop_exit;
2658 var = var + 1;
2659 goto loop_entry;
2660 loop_exit:
2661
2662 We increment var _after_ the loop exit check because we might otherwise
2663 fail if upper == TYPE_MAX_VALUE (type for upper).
2664
2665 Note that we never have to deal with SAVE_EXPRs here, because this has
2666 already been taken care of for us, in gimplify_init_ctor_preeval(). */
2667
2668 static void gimplify_init_ctor_eval (tree, VEC(constructor_elt,gc) *,
2669 tree *, bool);
2670
2671 static void
2672 gimplify_init_ctor_eval_range (tree object, tree lower, tree upper,
2673 tree value, tree array_elt_type,
2674 tree *pre_p, bool cleared)
2675 {
2676 tree loop_entry_label, loop_exit_label;
2677 tree var, var_type, cref;
2678
2679 loop_entry_label = create_artificial_label ();
2680 loop_exit_label = create_artificial_label ();
2681
2682 /* Create and initialize the index variable. */
2683 var_type = TREE_TYPE (upper);
2684 var = create_tmp_var (var_type, NULL);
2685 append_to_statement_list (build2 (MODIFY_EXPR, var_type, var, lower), pre_p);
2686
2687 /* Add the loop entry label. */
2688 append_to_statement_list (build1 (LABEL_EXPR,
2689 void_type_node,
2690 loop_entry_label),
2691 pre_p);
2692
2693 /* Build the reference. */
2694 cref = build4 (ARRAY_REF, array_elt_type, unshare_expr (object),
2695 var, NULL_TREE, NULL_TREE);
2696
2697 /* If we are a constructor, just call gimplify_init_ctor_eval to do
2698 the store. Otherwise just assign value to the reference. */
2699
2700 if (TREE_CODE (value) == CONSTRUCTOR)
2701 /* NB we might have to call ourself recursively through
2702 gimplify_init_ctor_eval if the value is a constructor. */
2703 gimplify_init_ctor_eval (cref, CONSTRUCTOR_ELTS (value),
2704 pre_p, cleared);
2705 else
2706 append_to_statement_list (build2 (MODIFY_EXPR, TREE_TYPE (cref),
2707 cref, value),
2708 pre_p);
2709
2710 /* We exit the loop when the index var is equal to the upper bound. */
2711 gimplify_and_add (build3 (COND_EXPR, void_type_node,
2712 build2 (EQ_EXPR, boolean_type_node,
2713 var, upper),
2714 build1 (GOTO_EXPR,
2715 void_type_node,
2716 loop_exit_label),
2717 NULL_TREE),
2718 pre_p);
2719
2720 /* Otherwise, increment the index var... */
2721 append_to_statement_list (build2 (MODIFY_EXPR, var_type, var,
2722 build2 (PLUS_EXPR, var_type, var,
2723 fold_convert (var_type,
2724 integer_one_node))),
2725 pre_p);
2726
2727 /* ...and jump back to the loop entry. */
2728 append_to_statement_list (build1 (GOTO_EXPR,
2729 void_type_node,
2730 loop_entry_label),
2731 pre_p);
2732
2733 /* Add the loop exit label. */
2734 append_to_statement_list (build1 (LABEL_EXPR,
2735 void_type_node,
2736 loop_exit_label),
2737 pre_p);
2738 }
2739
2740 /* Return true if FDECL is accessing a field that is zero sized. */
2741
2742 static bool
2743 zero_sized_field_decl (tree fdecl)
2744 {
2745 if (TREE_CODE (fdecl) == FIELD_DECL && DECL_SIZE (fdecl)
2746 && integer_zerop (DECL_SIZE (fdecl)))
2747 return true;
2748 return false;
2749 }
2750
2751 /* Return true if TYPE is zero sized. */
2752
2753 static bool
2754 zero_sized_type (tree type)
2755 {
2756 if (AGGREGATE_TYPE_P (type) && TYPE_SIZE (type)
2757 && integer_zerop (TYPE_SIZE (type)))
2758 return true;
2759 return false;
2760 }
2761
2762 /* A subroutine of gimplify_init_constructor. Generate individual
2763 MODIFY_EXPRs for a CONSTRUCTOR. OBJECT is the LHS against which the
2764 assignments should happen. ELTS is the CONSTRUCTOR_ELTS of the
2765 CONSTRUCTOR. CLEARED is true if the entire LHS object has been
2766 zeroed first. */
2767
2768 static void
2769 gimplify_init_ctor_eval (tree object, VEC(constructor_elt,gc) *elts,
2770 tree *pre_p, bool cleared)
2771 {
2772 tree array_elt_type = NULL;
2773 unsigned HOST_WIDE_INT ix;
2774 tree purpose, value;
2775
2776 if (TREE_CODE (TREE_TYPE (object)) == ARRAY_TYPE)
2777 array_elt_type = TYPE_MAIN_VARIANT (TREE_TYPE (TREE_TYPE (object)));
2778
2779 FOR_EACH_CONSTRUCTOR_ELT (elts, ix, purpose, value)
2780 {
2781 tree cref, init;
2782
2783 /* NULL values are created above for gimplification errors. */
2784 if (value == NULL)
2785 continue;
2786
2787 if (cleared && initializer_zerop (value))
2788 continue;
2789
2790 /* ??? Here's to hoping the front end fills in all of the indices,
2791 so we don't have to figure out what's missing ourselves. */
2792 gcc_assert (purpose);
2793
2794 /* Skip zero-sized fields, unless value has side-effects. This can
2795 happen with calls to functions returning a zero-sized type, which
2796 we shouldn't discard. As a number of downstream passes don't
2797 expect sets of zero-sized fields, we rely on the gimplification of
2798 the MODIFY_EXPR we make below to drop the assignment statement. */
2799 if (! TREE_SIDE_EFFECTS (value) && zero_sized_field_decl (purpose))
2800 continue;
2801
2802 /* If we have a RANGE_EXPR, we have to build a loop to assign the
2803 whole range. */
2804 if (TREE_CODE (purpose) == RANGE_EXPR)
2805 {
2806 tree lower = TREE_OPERAND (purpose, 0);
2807 tree upper = TREE_OPERAND (purpose, 1);
2808
2809 /* If the lower bound is equal to upper, just treat it as if
2810 upper was the index. */
2811 if (simple_cst_equal (lower, upper))
2812 purpose = upper;
2813 else
2814 {
2815 gimplify_init_ctor_eval_range (object, lower, upper, value,
2816 array_elt_type, pre_p, cleared);
2817 continue;
2818 }
2819 }
2820
2821 if (array_elt_type)
2822 {
2823 cref = build4 (ARRAY_REF, array_elt_type, unshare_expr (object),
2824 purpose, NULL_TREE, NULL_TREE);
2825 }
2826 else
2827 {
2828 gcc_assert (TREE_CODE (purpose) == FIELD_DECL);
2829 cref = build3 (COMPONENT_REF, TREE_TYPE (purpose),
2830 unshare_expr (object), purpose, NULL_TREE);
2831 }
2832
2833 if (TREE_CODE (value) == CONSTRUCTOR
2834 && TREE_CODE (TREE_TYPE (value)) != VECTOR_TYPE)
2835 gimplify_init_ctor_eval (cref, CONSTRUCTOR_ELTS (value),
2836 pre_p, cleared);
2837 else
2838 {
2839 init = build2 (MODIFY_EXPR, TREE_TYPE (cref), cref, value);
2840 gimplify_and_add (init, pre_p);
2841 }
2842 }
2843 }
2844
2845 /* A subroutine of gimplify_modify_expr. Break out elements of a
2846 CONSTRUCTOR used as an initializer into separate MODIFY_EXPRs.
2847
2848 Note that we still need to clear any elements that don't have explicit
2849 initializers, so if not all elements are initialized we keep the
2850 original MODIFY_EXPR, we just remove all of the constructor elements. */
2851
2852 static enum gimplify_status
2853 gimplify_init_constructor (tree *expr_p, tree *pre_p,
2854 tree *post_p, bool want_value)
2855 {
2856 tree object;
2857 tree ctor = TREE_OPERAND (*expr_p, 1);
2858 tree type = TREE_TYPE (ctor);
2859 enum gimplify_status ret;
2860 VEC(constructor_elt,gc) *elts;
2861
2862 if (TREE_CODE (ctor) != CONSTRUCTOR)
2863 return GS_UNHANDLED;
2864
2865 ret = gimplify_expr (&TREE_OPERAND (*expr_p, 0), pre_p, post_p,
2866 is_gimple_lvalue, fb_lvalue);
2867 if (ret == GS_ERROR)
2868 return ret;
2869 object = TREE_OPERAND (*expr_p, 0);
2870
2871 elts = CONSTRUCTOR_ELTS (ctor);
2872
2873 ret = GS_ALL_DONE;
2874 switch (TREE_CODE (type))
2875 {
2876 case RECORD_TYPE:
2877 case UNION_TYPE:
2878 case QUAL_UNION_TYPE:
2879 case ARRAY_TYPE:
2880 {
2881 struct gimplify_init_ctor_preeval_data preeval_data;
2882 HOST_WIDE_INT num_type_elements, num_ctor_elements;
2883 HOST_WIDE_INT num_nonzero_elements, num_nonconstant_elements;
2884 bool cleared;
2885
2886 /* Aggregate types must lower constructors to initialization of
2887 individual elements. The exception is that a CONSTRUCTOR node
2888 with no elements indicates zero-initialization of the whole. */
2889 if (VEC_empty (constructor_elt, elts))
2890 break;
2891
2892 categorize_ctor_elements (ctor, &num_nonzero_elements,
2893 &num_nonconstant_elements,
2894 &num_ctor_elements, &cleared);
2895
2896 /* If a const aggregate variable is being initialized, then it
2897 should never be a lose to promote the variable to be static. */
2898 if (num_nonconstant_elements == 0
2899 && num_nonzero_elements > 1
2900 && TREE_READONLY (object)
2901 && TREE_CODE (object) == VAR_DECL)
2902 {
2903 DECL_INITIAL (object) = ctor;
2904 TREE_STATIC (object) = 1;
2905 if (!DECL_NAME (object))
2906 DECL_NAME (object) = create_tmp_var_name ("C");
2907 walk_tree (&DECL_INITIAL (object), force_labels_r, NULL, NULL);
2908
2909 /* ??? C++ doesn't automatically append a .<number> to the
2910 assembler name, and even when it does, it looks a FE private
2911 data structures to figure out what that number should be,
2912 which are not set for this variable. I suppose this is
2913 important for local statics for inline functions, which aren't
2914 "local" in the object file sense. So in order to get a unique
2915 TU-local symbol, we must invoke the lhd version now. */
2916 lhd_set_decl_assembler_name (object);
2917
2918 *expr_p = NULL_TREE;
2919 break;
2920 }
2921
2922 /* If there are "lots" of initialized elements, even discounting
2923 those that are not address constants (and thus *must* be
2924 computed at runtime), then partition the constructor into
2925 constant and non-constant parts. Block copy the constant
2926 parts in, then generate code for the non-constant parts. */
2927 /* TODO. There's code in cp/typeck.c to do this. */
2928
2929 num_type_elements = count_type_elements (type, true);
2930
2931 /* If count_type_elements could not determine number of type elements
2932 for a constant-sized object, assume clearing is needed.
2933 Don't do this for variable-sized objects, as store_constructor
2934 will ignore the clearing of variable-sized objects. */
2935 if (num_type_elements < 0 && int_size_in_bytes (type) >= 0)
2936 cleared = true;
2937 /* If there are "lots" of zeros, then block clear the object first. */
2938 else if (num_type_elements - num_nonzero_elements > CLEAR_RATIO
2939 && num_nonzero_elements < num_type_elements/4)
2940 cleared = true;
2941 /* ??? This bit ought not be needed. For any element not present
2942 in the initializer, we should simply set them to zero. Except
2943 we'd need to *find* the elements that are not present, and that
2944 requires trickery to avoid quadratic compile-time behavior in
2945 large cases or excessive memory use in small cases. */
2946 else if (num_ctor_elements < num_type_elements)
2947 cleared = true;
2948
2949 /* If there are "lots" of initialized elements, and all of them
2950 are valid address constants, then the entire initializer can
2951 be dropped to memory, and then memcpy'd out. Don't do this
2952 for sparse arrays, though, as it's more efficient to follow
2953 the standard CONSTRUCTOR behavior of memset followed by
2954 individual element initialization. */
2955 if (num_nonconstant_elements == 0 && !cleared)
2956 {
2957 HOST_WIDE_INT size = int_size_in_bytes (type);
2958 unsigned int align;
2959
2960 /* ??? We can still get unbounded array types, at least
2961 from the C++ front end. This seems wrong, but attempt
2962 to work around it for now. */
2963 if (size < 0)
2964 {
2965 size = int_size_in_bytes (TREE_TYPE (object));
2966 if (size >= 0)
2967 TREE_TYPE (ctor) = type = TREE_TYPE (object);
2968 }
2969
2970 /* Find the maximum alignment we can assume for the object. */
2971 /* ??? Make use of DECL_OFFSET_ALIGN. */
2972 if (DECL_P (object))
2973 align = DECL_ALIGN (object);
2974 else
2975 align = TYPE_ALIGN (type);
2976
2977 if (size > 0 && !can_move_by_pieces (size, align))
2978 {
2979 tree new = create_tmp_var_raw (type, "C");
2980
2981 gimple_add_tmp_var (new);
2982 TREE_STATIC (new) = 1;
2983 TREE_READONLY (new) = 1;
2984 DECL_INITIAL (new) = ctor;
2985 if (align > DECL_ALIGN (new))
2986 {
2987 DECL_ALIGN (new) = align;
2988 DECL_USER_ALIGN (new) = 1;
2989 }
2990 walk_tree (&DECL_INITIAL (new), force_labels_r, NULL, NULL);
2991
2992 TREE_OPERAND (*expr_p, 1) = new;
2993
2994 /* This is no longer an assignment of a CONSTRUCTOR, but
2995 we still may have processing to do on the LHS. So
2996 pretend we didn't do anything here to let that happen. */
2997 return GS_UNHANDLED;
2998 }
2999 }
3000
3001 if (cleared)
3002 {
3003 /* Zap the CONSTRUCTOR element list, which simplifies this case.
3004 Note that we still have to gimplify, in order to handle the
3005 case of variable sized types. Avoid shared tree structures. */
3006 CONSTRUCTOR_ELTS (ctor) = NULL;
3007 object = unshare_expr (object);
3008 gimplify_stmt (expr_p);
3009 append_to_statement_list (*expr_p, pre_p);
3010 }
3011
3012 /* If we have not block cleared the object, or if there are nonzero
3013 elements in the constructor, add assignments to the individual
3014 scalar fields of the object. */
3015 if (!cleared || num_nonzero_elements > 0)
3016 {
3017 preeval_data.lhs_base_decl = get_base_address (object);
3018 if (!DECL_P (preeval_data.lhs_base_decl))
3019 preeval_data.lhs_base_decl = NULL;
3020 preeval_data.lhs_alias_set = get_alias_set (object);
3021
3022 gimplify_init_ctor_preeval (&TREE_OPERAND (*expr_p, 1),
3023 pre_p, post_p, &preeval_data);
3024 gimplify_init_ctor_eval (object, elts, pre_p, cleared);
3025 }
3026
3027 *expr_p = NULL_TREE;
3028 }
3029 break;
3030
3031 case COMPLEX_TYPE:
3032 {
3033 tree r, i;
3034
3035 /* Extract the real and imaginary parts out of the ctor. */
3036 gcc_assert (VEC_length (constructor_elt, elts) == 2);
3037 r = VEC_index (constructor_elt, elts, 0)->value;
3038 i = VEC_index (constructor_elt, elts, 1)->value;
3039 if (r == NULL || i == NULL)
3040 {
3041 tree zero = convert (TREE_TYPE (type), integer_zero_node);
3042 if (r == NULL)
3043 r = zero;
3044 if (i == NULL)
3045 i = zero;
3046 }
3047
3048 /* Complex types have either COMPLEX_CST or COMPLEX_EXPR to
3049 represent creation of a complex value. */
3050 if (TREE_CONSTANT (r) && TREE_CONSTANT (i))
3051 {
3052 ctor = build_complex (type, r, i);
3053 TREE_OPERAND (*expr_p, 1) = ctor;
3054 }
3055 else
3056 {
3057 ctor = build2 (COMPLEX_EXPR, type, r, i);
3058 TREE_OPERAND (*expr_p, 1) = ctor;
3059 ret = gimplify_expr (&TREE_OPERAND (*expr_p, 1), pre_p, post_p,
3060 rhs_predicate_for (TREE_OPERAND (*expr_p, 0)),
3061 fb_rvalue);
3062 }
3063 }
3064 break;
3065
3066 case VECTOR_TYPE:
3067 {
3068 unsigned HOST_WIDE_INT ix;
3069 constructor_elt *ce;
3070
3071 /* Go ahead and simplify constant constructors to VECTOR_CST. */
3072 if (TREE_CONSTANT (ctor))
3073 {
3074 bool constant_p = true;
3075 tree value;
3076
3077 /* Even when ctor is constant, it might contain non-*_CST
3078 elements (e.g. { 1.0/0.0 - 1.0/0.0, 0.0 }) and those don't
3079 belong into VECTOR_CST nodes. */
3080 FOR_EACH_CONSTRUCTOR_VALUE (elts, ix, value)
3081 if (!CONSTANT_CLASS_P (value))
3082 {
3083 constant_p = false;
3084 break;
3085 }
3086
3087 if (constant_p)
3088 {
3089 TREE_OPERAND (*expr_p, 1) = build_vector_from_ctor (type, elts);
3090 break;
3091 }
3092 }
3093
3094 /* Vector types use CONSTRUCTOR all the way through gimple
3095 compilation as a general initializer. */
3096 for (ix = 0; VEC_iterate (constructor_elt, elts, ix, ce); ix++)
3097 {
3098 enum gimplify_status tret;
3099 tret = gimplify_expr (&ce->value, pre_p, post_p,
3100 is_gimple_val, fb_rvalue);
3101 if (tret == GS_ERROR)
3102 ret = GS_ERROR;
3103 }
3104 }
3105 break;
3106
3107 default:
3108 /* So how did we get a CONSTRUCTOR for a scalar type? */
3109 gcc_unreachable ();
3110 }
3111
3112 if (ret == GS_ERROR)
3113 return GS_ERROR;
3114 else if (want_value)
3115 {
3116 append_to_statement_list (*expr_p, pre_p);
3117 *expr_p = object;
3118 return GS_OK;
3119 }
3120 else
3121 return GS_ALL_DONE;
3122 }
3123
3124 /* Given a pointer value OP0, return a simplified version of an
3125 indirection through OP0, or NULL_TREE if no simplification is
3126 possible. This may only be applied to a rhs of an expression.
3127 Note that the resulting type may be different from the type pointed
3128 to in the sense that it is still compatible from the langhooks
3129 point of view. */
3130
3131 static tree
3132 fold_indirect_ref_rhs (tree t)
3133 {
3134 tree type = TREE_TYPE (TREE_TYPE (t));
3135 tree sub = t;
3136 tree subtype;
3137
3138 STRIP_NOPS (sub);
3139 subtype = TREE_TYPE (sub);
3140 if (!POINTER_TYPE_P (subtype))
3141 return NULL_TREE;
3142
3143 if (TREE_CODE (sub) == ADDR_EXPR)
3144 {
3145 tree op = TREE_OPERAND (sub, 0);
3146 tree optype = TREE_TYPE (op);
3147 /* *&p => p */
3148 if (lang_hooks.types_compatible_p (type, optype))
3149 return op;
3150 /* *(foo *)&fooarray => fooarray[0] */
3151 else if (TREE_CODE (optype) == ARRAY_TYPE
3152 && lang_hooks.types_compatible_p (type, TREE_TYPE (optype)))
3153 {
3154 tree type_domain = TYPE_DOMAIN (optype);
3155 tree min_val = size_zero_node;
3156 if (type_domain && TYPE_MIN_VALUE (type_domain))
3157 min_val = TYPE_MIN_VALUE (type_domain);
3158 return build4 (ARRAY_REF, type, op, min_val, NULL_TREE, NULL_TREE);
3159 }
3160 }
3161
3162 /* *(foo *)fooarrptr => (*fooarrptr)[0] */
3163 if (TREE_CODE (TREE_TYPE (subtype)) == ARRAY_TYPE
3164 && lang_hooks.types_compatible_p (type, TREE_TYPE (TREE_TYPE (subtype))))
3165 {
3166 tree type_domain;
3167 tree min_val = size_zero_node;
3168 tree osub = sub;
3169 sub = fold_indirect_ref_rhs (sub);
3170 if (! sub)
3171 sub = build1 (INDIRECT_REF, TREE_TYPE (subtype), osub);
3172 type_domain = TYPE_DOMAIN (TREE_TYPE (sub));
3173 if (type_domain && TYPE_MIN_VALUE (type_domain))
3174 min_val = TYPE_MIN_VALUE (type_domain);
3175 return build4 (ARRAY_REF, type, sub, min_val, NULL_TREE, NULL_TREE);
3176 }
3177
3178 return NULL_TREE;
3179 }
3180
3181 /* Subroutine of gimplify_modify_expr to do simplifications of MODIFY_EXPRs
3182 based on the code of the RHS. We loop for as long as something changes. */
3183
3184 static enum gimplify_status
3185 gimplify_modify_expr_rhs (tree *expr_p, tree *from_p, tree *to_p, tree *pre_p,
3186 tree *post_p, bool want_value)
3187 {
3188 enum gimplify_status ret = GS_OK;
3189
3190 while (ret != GS_UNHANDLED)
3191 switch (TREE_CODE (*from_p))
3192 {
3193 case INDIRECT_REF:
3194 {
3195 /* If we have code like
3196
3197 *(const A*)(A*)&x
3198
3199 where the type of "x" is a (possibly cv-qualified variant
3200 of "A"), treat the entire expression as identical to "x".
3201 This kind of code arises in C++ when an object is bound
3202 to a const reference, and if "x" is a TARGET_EXPR we want
3203 to take advantage of the optimization below. */
3204 tree t = fold_indirect_ref_rhs (TREE_OPERAND (*from_p, 0));
3205 if (t)
3206 {
3207 *from_p = t;
3208 ret = GS_OK;
3209 }
3210 else
3211 ret = GS_UNHANDLED;
3212 break;
3213 }
3214
3215 case TARGET_EXPR:
3216 {
3217 /* If we are initializing something from a TARGET_EXPR, strip the
3218 TARGET_EXPR and initialize it directly, if possible. This can't
3219 be done if the initializer is void, since that implies that the
3220 temporary is set in some non-trivial way.
3221
3222 ??? What about code that pulls out the temp and uses it
3223 elsewhere? I think that such code never uses the TARGET_EXPR as
3224 an initializer. If I'm wrong, we'll die because the temp won't
3225 have any RTL. In that case, I guess we'll need to replace
3226 references somehow. */
3227 tree init = TARGET_EXPR_INITIAL (*from_p);
3228
3229 if (!VOID_TYPE_P (TREE_TYPE (init)))
3230 {
3231 *from_p = init;
3232 ret = GS_OK;
3233 }
3234 else
3235 ret = GS_UNHANDLED;
3236 }
3237 break;
3238
3239 case COMPOUND_EXPR:
3240 /* Remove any COMPOUND_EXPR in the RHS so the following cases will be
3241 caught. */
3242 gimplify_compound_expr (from_p, pre_p, true);
3243 ret = GS_OK;
3244 break;
3245
3246 case CONSTRUCTOR:
3247 /* If we're initializing from a CONSTRUCTOR, break this into
3248 individual MODIFY_EXPRs. */
3249 return gimplify_init_constructor (expr_p, pre_p, post_p, want_value);
3250
3251 case COND_EXPR:
3252 /* If we're assigning to a non-register type, push the assignment
3253 down into the branches. This is mandatory for ADDRESSABLE types,
3254 since we cannot generate temporaries for such, but it saves a
3255 copy in other cases as well. */
3256 if (!is_gimple_reg_type (TREE_TYPE (*from_p)))
3257 {
3258 *expr_p = *from_p;
3259 return gimplify_cond_expr (expr_p, pre_p, post_p, *to_p,
3260 fb_rvalue);
3261 }
3262 else
3263 ret = GS_UNHANDLED;
3264 break;
3265
3266 case CALL_EXPR:
3267 /* For calls that return in memory, give *to_p as the CALL_EXPR's
3268 return slot so that we don't generate a temporary. */
3269 if (!CALL_EXPR_RETURN_SLOT_OPT (*from_p)
3270 && aggregate_value_p (*from_p, *from_p))
3271 {
3272 bool use_target;
3273
3274 if (TREE_CODE (*to_p) == RESULT_DECL
3275 && needs_to_live_in_memory (*to_p))
3276 /* It's always OK to use the return slot directly. */
3277 use_target = true;
3278 else if (!is_gimple_non_addressable (*to_p))
3279 /* Don't use the original target if it's already addressable;
3280 if its address escapes, and the called function uses the
3281 NRV optimization, a conforming program could see *to_p
3282 change before the called function returns; see c++/19317.
3283 When optimizing, the return_slot pass marks more functions
3284 as safe after we have escape info. */
3285 use_target = false;
3286 else if (TREE_CODE (*to_p) != PARM_DECL
3287 && DECL_GIMPLE_FORMAL_TEMP_P (*to_p))
3288 /* Don't use the original target if it's a formal temp; we
3289 don't want to take their addresses. */
3290 use_target = false;
3291 else if (is_gimple_reg_type (TREE_TYPE (*to_p)))
3292 /* Also don't force regs into memory. */
3293 use_target = false;
3294 else
3295 use_target = true;
3296
3297 if (use_target)
3298 {
3299 CALL_EXPR_RETURN_SLOT_OPT (*from_p) = 1;
3300 lang_hooks.mark_addressable (*to_p);
3301 }
3302 }
3303
3304 ret = GS_UNHANDLED;
3305 break;
3306
3307 default:
3308 ret = GS_UNHANDLED;
3309 break;
3310 }
3311
3312 return ret;
3313 }
3314
3315 /* Promote partial stores to COMPLEX variables to total stores. *EXPR_P is
3316 a MODIFY_EXPR with a lhs of a REAL/IMAGPART_EXPR of a variable with
3317 DECL_COMPLEX_GIMPLE_REG_P set. */
3318
3319 static enum gimplify_status
3320 gimplify_modify_expr_complex_part (tree *expr_p, tree *pre_p, bool want_value)
3321 {
3322 enum tree_code code, ocode;
3323 tree lhs, rhs, new_rhs, other, realpart, imagpart;
3324
3325 lhs = TREE_OPERAND (*expr_p, 0);
3326 rhs = TREE_OPERAND (*expr_p, 1);
3327 code = TREE_CODE (lhs);
3328 lhs = TREE_OPERAND (lhs, 0);
3329
3330 ocode = code == REALPART_EXPR ? IMAGPART_EXPR : REALPART_EXPR;
3331 other = build1 (ocode, TREE_TYPE (rhs), lhs);
3332 other = get_formal_tmp_var (other, pre_p);
3333
3334 realpart = code == REALPART_EXPR ? rhs : other;
3335 imagpart = code == REALPART_EXPR ? other : rhs;
3336
3337 if (TREE_CONSTANT (realpart) && TREE_CONSTANT (imagpart))
3338 new_rhs = build_complex (TREE_TYPE (lhs), realpart, imagpart);
3339 else
3340 new_rhs = build2 (COMPLEX_EXPR, TREE_TYPE (lhs), realpart, imagpart);
3341
3342 TREE_OPERAND (*expr_p, 0) = lhs;
3343 TREE_OPERAND (*expr_p, 1) = new_rhs;
3344
3345 if (want_value)
3346 {
3347 append_to_statement_list (*expr_p, pre_p);
3348 *expr_p = rhs;
3349 }
3350
3351 return GS_ALL_DONE;
3352 }
3353
3354 /* Gimplify the MODIFY_EXPR node pointed to by EXPR_P.
3355
3356 modify_expr
3357 : varname '=' rhs
3358 | '*' ID '=' rhs
3359
3360 PRE_P points to the list where side effects that must happen before
3361 *EXPR_P should be stored.
3362
3363 POST_P points to the list where side effects that must happen after
3364 *EXPR_P should be stored.
3365
3366 WANT_VALUE is nonzero iff we want to use the value of this expression
3367 in another expression. */
3368
3369 static enum gimplify_status
3370 gimplify_modify_expr (tree *expr_p, tree *pre_p, tree *post_p, bool want_value)
3371 {
3372 tree *from_p = &TREE_OPERAND (*expr_p, 1);
3373 tree *to_p = &TREE_OPERAND (*expr_p, 0);
3374 enum gimplify_status ret = GS_UNHANDLED;
3375
3376 gcc_assert (TREE_CODE (*expr_p) == MODIFY_EXPR
3377 || TREE_CODE (*expr_p) == INIT_EXPR);
3378
3379 /* The distinction between MODIFY_EXPR and INIT_EXPR is no longer useful. */
3380 if (TREE_CODE (*expr_p) == INIT_EXPR)
3381 TREE_SET_CODE (*expr_p, MODIFY_EXPR);
3382
3383 /* For zero sized types only gimplify the left hand side and right hand side
3384 as statements and throw away the assignment. */
3385 if (zero_sized_type (TREE_TYPE (*from_p)))
3386 {
3387 gimplify_stmt (from_p);
3388 gimplify_stmt (to_p);
3389 append_to_statement_list (*from_p, pre_p);
3390 append_to_statement_list (*to_p, pre_p);
3391 *expr_p = NULL_TREE;
3392 return GS_ALL_DONE;
3393 }
3394
3395 /* See if any simplifications can be done based on what the RHS is. */
3396 ret = gimplify_modify_expr_rhs (expr_p, from_p, to_p, pre_p, post_p,
3397 want_value);
3398 if (ret != GS_UNHANDLED)
3399 return ret;
3400
3401 /* If the value being copied is of variable width, compute the length
3402 of the copy into a WITH_SIZE_EXPR. Note that we need to do this
3403 before gimplifying any of the operands so that we can resolve any
3404 PLACEHOLDER_EXPRs in the size. Also note that the RTL expander uses
3405 the size of the expression to be copied, not of the destination, so
3406 that is what we must here. */
3407 maybe_with_size_expr (from_p);
3408
3409 ret = gimplify_expr (to_p, pre_p, post_p, is_gimple_lvalue, fb_lvalue);
3410 if (ret == GS_ERROR)
3411 return ret;
3412
3413 ret = gimplify_expr (from_p, pre_p, post_p,
3414 rhs_predicate_for (*to_p), fb_rvalue);
3415 if (ret == GS_ERROR)
3416 return ret;
3417
3418 /* Now see if the above changed *from_p to something we handle specially. */
3419 ret = gimplify_modify_expr_rhs (expr_p, from_p, to_p, pre_p, post_p,
3420 want_value);
3421 if (ret != GS_UNHANDLED)
3422 return ret;
3423
3424 /* If we've got a variable sized assignment between two lvalues (i.e. does
3425 not involve a call), then we can make things a bit more straightforward
3426 by converting the assignment to memcpy or memset. */
3427 if (TREE_CODE (*from_p) == WITH_SIZE_EXPR)
3428 {
3429 tree from = TREE_OPERAND (*from_p, 0);
3430 tree size = TREE_OPERAND (*from_p, 1);
3431
3432 if (TREE_CODE (from) == CONSTRUCTOR)
3433 return gimplify_modify_expr_to_memset (expr_p, size, want_value);
3434 if (is_gimple_addressable (from))
3435 {
3436 *from_p = from;
3437 return gimplify_modify_expr_to_memcpy (expr_p, size, want_value);
3438 }
3439 }
3440
3441 /* Transform partial stores to non-addressable complex variables into
3442 total stores. This allows us to use real instead of virtual operands
3443 for these variables, which improves optimization. */
3444 if ((TREE_CODE (*to_p) == REALPART_EXPR
3445 || TREE_CODE (*to_p) == IMAGPART_EXPR)
3446 && is_gimple_reg (TREE_OPERAND (*to_p, 0)))
3447 return gimplify_modify_expr_complex_part (expr_p, pre_p, want_value);
3448
3449 if (gimplify_ctxp->into_ssa && is_gimple_reg (*to_p))
3450 {
3451 /* If we've somehow already got an SSA_NAME on the LHS, then
3452 we're probably modified it twice. Not good. */
3453 gcc_assert (TREE_CODE (*to_p) != SSA_NAME);
3454 *to_p = make_ssa_name (*to_p, *expr_p);
3455 }
3456
3457 if (want_value)
3458 {
3459 append_to_statement_list (*expr_p, pre_p);
3460 *expr_p = *to_p;
3461 return GS_OK;
3462 }
3463
3464 return GS_ALL_DONE;
3465 }
3466
3467 /* Gimplify a comparison between two variable-sized objects. Do this
3468 with a call to BUILT_IN_MEMCMP. */
3469
3470 static enum gimplify_status
3471 gimplify_variable_sized_compare (tree *expr_p)
3472 {
3473 tree op0 = TREE_OPERAND (*expr_p, 0);
3474 tree op1 = TREE_OPERAND (*expr_p, 1);
3475 tree args, t, dest;
3476
3477 t = TYPE_SIZE_UNIT (TREE_TYPE (op0));
3478 t = unshare_expr (t);
3479 t = SUBSTITUTE_PLACEHOLDER_IN_EXPR (t, op0);
3480 args = tree_cons (NULL, t, NULL);
3481 t = build_fold_addr_expr (op1);
3482 args = tree_cons (NULL, t, args);
3483 dest = build_fold_addr_expr (op0);
3484 args = tree_cons (NULL, dest, args);
3485 t = implicit_built_in_decls[BUILT_IN_MEMCMP];
3486 t = build_function_call_expr (t, args);
3487 *expr_p
3488 = build2 (TREE_CODE (*expr_p), TREE_TYPE (*expr_p), t, integer_zero_node);
3489
3490 return GS_OK;
3491 }
3492
3493 /* Gimplify TRUTH_ANDIF_EXPR and TRUTH_ORIF_EXPR expressions. EXPR_P
3494 points to the expression to gimplify.
3495
3496 Expressions of the form 'a && b' are gimplified to:
3497
3498 a && b ? true : false
3499
3500 gimplify_cond_expr will do the rest.
3501
3502 PRE_P points to the list where side effects that must happen before
3503 *EXPR_P should be stored. */
3504
3505 static enum gimplify_status
3506 gimplify_boolean_expr (tree *expr_p)
3507 {
3508 /* Preserve the original type of the expression. */
3509 tree type = TREE_TYPE (*expr_p);
3510
3511 *expr_p = build3 (COND_EXPR, type, *expr_p,
3512 convert (type, boolean_true_node),
3513 convert (type, boolean_false_node));
3514
3515 return GS_OK;
3516 }
3517
3518 /* Gimplifies an expression sequence. This function gimplifies each
3519 expression and re-writes the original expression with the last
3520 expression of the sequence in GIMPLE form.
3521
3522 PRE_P points to the list where the side effects for all the
3523 expressions in the sequence will be emitted.
3524
3525 WANT_VALUE is true when the result of the last COMPOUND_EXPR is used. */
3526 /* ??? Should rearrange to share the pre-queue with all the indirect
3527 invocations of gimplify_expr. Would probably save on creations
3528 of statement_list nodes. */
3529
3530 static enum gimplify_status
3531 gimplify_compound_expr (tree *expr_p, tree *pre_p, bool want_value)
3532 {
3533 tree t = *expr_p;
3534
3535 do
3536 {
3537 tree *sub_p = &TREE_OPERAND (t, 0);
3538
3539 if (TREE_CODE (*sub_p) == COMPOUND_EXPR)
3540 gimplify_compound_expr (sub_p, pre_p, false);
3541 else
3542 gimplify_stmt (sub_p);
3543 append_to_statement_list (*sub_p, pre_p);
3544
3545 t = TREE_OPERAND (t, 1);
3546 }
3547 while (TREE_CODE (t) == COMPOUND_EXPR);
3548
3549 *expr_p = t;
3550 if (want_value)
3551 return GS_OK;
3552 else
3553 {
3554 gimplify_stmt (expr_p);
3555 return GS_ALL_DONE;
3556 }
3557 }
3558
3559 /* Gimplifies a statement list. These may be created either by an
3560 enlightened front-end, or by shortcut_cond_expr. */
3561
3562 static enum gimplify_status
3563 gimplify_statement_list (tree *expr_p)
3564 {
3565 tree_stmt_iterator i = tsi_start (*expr_p);
3566
3567 while (!tsi_end_p (i))
3568 {
3569 tree t;
3570
3571 gimplify_stmt (tsi_stmt_ptr (i));
3572
3573 t = tsi_stmt (i);
3574 if (t == NULL)
3575 tsi_delink (&i);
3576 else if (TREE_CODE (t) == STATEMENT_LIST)
3577 {
3578 tsi_link_before (&i, t, TSI_SAME_STMT);
3579 tsi_delink (&i);
3580 }
3581 else
3582 tsi_next (&i);
3583 }
3584
3585 return GS_ALL_DONE;
3586 }
3587
3588 /* Gimplify a SAVE_EXPR node. EXPR_P points to the expression to
3589 gimplify. After gimplification, EXPR_P will point to a new temporary
3590 that holds the original value of the SAVE_EXPR node.
3591
3592 PRE_P points to the list where side effects that must happen before
3593 *EXPR_P should be stored. */
3594
3595 static enum gimplify_status
3596 gimplify_save_expr (tree *expr_p, tree *pre_p, tree *post_p)
3597 {
3598 enum gimplify_status ret = GS_ALL_DONE;
3599 tree val;
3600
3601 gcc_assert (TREE_CODE (*expr_p) == SAVE_EXPR);
3602 val = TREE_OPERAND (*expr_p, 0);
3603
3604 /* If the SAVE_EXPR has not been resolved, then evaluate it once. */
3605 if (!SAVE_EXPR_RESOLVED_P (*expr_p))
3606 {
3607 /* The operand may be a void-valued expression such as SAVE_EXPRs
3608 generated by the Java frontend for class initialization. It is
3609 being executed only for its side-effects. */
3610 if (TREE_TYPE (val) == void_type_node)
3611 {
3612 ret = gimplify_expr (&TREE_OPERAND (*expr_p, 0), pre_p, post_p,
3613 is_gimple_stmt, fb_none);
3614 append_to_statement_list (TREE_OPERAND (*expr_p, 0), pre_p);
3615 val = NULL;
3616 }
3617 else
3618 val = get_initialized_tmp_var (val, pre_p, post_p);
3619
3620 TREE_OPERAND (*expr_p, 0) = val;
3621 SAVE_EXPR_RESOLVED_P (*expr_p) = 1;
3622 }
3623
3624 *expr_p = val;
3625
3626 return ret;
3627 }
3628
3629 /* Re-write the ADDR_EXPR node pointed to by EXPR_P
3630
3631 unary_expr
3632 : ...
3633 | '&' varname
3634 ...
3635
3636 PRE_P points to the list where side effects that must happen before
3637 *EXPR_P should be stored.
3638
3639 POST_P points to the list where side effects that must happen after
3640 *EXPR_P should be stored. */
3641
3642 static enum gimplify_status
3643 gimplify_addr_expr (tree *expr_p, tree *pre_p, tree *post_p)
3644 {
3645 tree expr = *expr_p;
3646 tree op0 = TREE_OPERAND (expr, 0);
3647 enum gimplify_status ret;
3648
3649 switch (TREE_CODE (op0))
3650 {
3651 case INDIRECT_REF:
3652 case MISALIGNED_INDIRECT_REF:
3653 do_indirect_ref:
3654 /* Check if we are dealing with an expression of the form '&*ptr'.
3655 While the front end folds away '&*ptr' into 'ptr', these
3656 expressions may be generated internally by the compiler (e.g.,
3657 builtins like __builtin_va_end). */
3658 /* Caution: the silent array decomposition semantics we allow for
3659 ADDR_EXPR means we can't always discard the pair. */
3660 /* Gimplification of the ADDR_EXPR operand may drop
3661 cv-qualification conversions, so make sure we add them if
3662 needed. */
3663 {
3664 tree op00 = TREE_OPERAND (op0, 0);
3665 tree t_expr = TREE_TYPE (expr);
3666 tree t_op00 = TREE_TYPE (op00);
3667
3668 if (!lang_hooks.types_compatible_p (t_expr, t_op00))
3669 {
3670 #ifdef ENABLE_CHECKING
3671 tree t_op0 = TREE_TYPE (op0);
3672 gcc_assert (POINTER_TYPE_P (t_expr)
3673 && cpt_same_type (TREE_CODE (t_op0) == ARRAY_TYPE
3674 ? TREE_TYPE (t_op0) : t_op0,
3675 TREE_TYPE (t_expr))
3676 && POINTER_TYPE_P (t_op00)
3677 && cpt_same_type (t_op0, TREE_TYPE (t_op00)));
3678 #endif
3679 op00 = fold_convert (TREE_TYPE (expr), op00);
3680 }
3681 *expr_p = op00;
3682 ret = GS_OK;
3683 }
3684 break;
3685
3686 case VIEW_CONVERT_EXPR:
3687 /* Take the address of our operand and then convert it to the type of
3688 this ADDR_EXPR.
3689
3690 ??? The interactions of VIEW_CONVERT_EXPR and aliasing is not at
3691 all clear. The impact of this transformation is even less clear. */
3692
3693 /* If the operand is a useless conversion, look through it. Doing so
3694 guarantees that the ADDR_EXPR and its operand will remain of the
3695 same type. */
3696 if (tree_ssa_useless_type_conversion (TREE_OPERAND (op0, 0)))
3697 op0 = TREE_OPERAND (op0, 0);
3698
3699 *expr_p = fold_convert (TREE_TYPE (expr),
3700 build_fold_addr_expr (TREE_OPERAND (op0, 0)));
3701 ret = GS_OK;
3702 break;
3703
3704 default:
3705 /* We use fb_either here because the C frontend sometimes takes
3706 the address of a call that returns a struct; see
3707 gcc.dg/c99-array-lval-1.c. The gimplifier will correctly make
3708 the implied temporary explicit. */
3709 ret = gimplify_expr (&TREE_OPERAND (expr, 0), pre_p, post_p,
3710 is_gimple_addressable, fb_either);
3711 if (ret != GS_ERROR)
3712 {
3713 op0 = TREE_OPERAND (expr, 0);
3714
3715 /* For various reasons, the gimplification of the expression
3716 may have made a new INDIRECT_REF. */
3717 if (TREE_CODE (op0) == INDIRECT_REF)
3718 goto do_indirect_ref;
3719
3720 /* Make sure TREE_INVARIANT, TREE_CONSTANT, and TREE_SIDE_EFFECTS
3721 is set properly. */
3722 recompute_tree_invariant_for_addr_expr (expr);
3723
3724 /* Mark the RHS addressable. */
3725 lang_hooks.mark_addressable (TREE_OPERAND (expr, 0));
3726 }
3727 break;
3728 }
3729
3730 return ret;
3731 }
3732
3733 /* Gimplify the operands of an ASM_EXPR. Input operands should be a gimple
3734 value; output operands should be a gimple lvalue. */
3735
3736 static enum gimplify_status
3737 gimplify_asm_expr (tree *expr_p, tree *pre_p, tree *post_p)
3738 {
3739 tree expr = *expr_p;
3740 int noutputs = list_length (ASM_OUTPUTS (expr));
3741 const char **oconstraints
3742 = (const char **) alloca ((noutputs) * sizeof (const char *));
3743 int i;
3744 tree link;
3745 const char *constraint;
3746 bool allows_mem, allows_reg, is_inout;
3747 enum gimplify_status ret, tret;
3748
3749 ret = GS_ALL_DONE;
3750 for (i = 0, link = ASM_OUTPUTS (expr); link; ++i, link = TREE_CHAIN (link))
3751 {
3752 size_t constraint_len;
3753 oconstraints[i] = constraint
3754 = TREE_STRING_POINTER (TREE_VALUE (TREE_PURPOSE (link)));
3755 constraint_len = strlen (constraint);
3756 if (constraint_len == 0)
3757 continue;
3758
3759 parse_output_constraint (&constraint, i, 0, 0,
3760 &allows_mem, &allows_reg, &is_inout);
3761
3762 if (!allows_reg && allows_mem)
3763 lang_hooks.mark_addressable (TREE_VALUE (link));
3764
3765 tret = gimplify_expr (&TREE_VALUE (link), pre_p, post_p,
3766 is_inout ? is_gimple_min_lval : is_gimple_lvalue,
3767 fb_lvalue | fb_mayfail);
3768 if (tret == GS_ERROR)
3769 {
3770 error ("invalid lvalue in asm output %d", i);
3771 ret = tret;
3772 }
3773
3774 if (is_inout)
3775 {
3776 /* An input/output operand. To give the optimizers more
3777 flexibility, split it into separate input and output
3778 operands. */
3779 tree input;
3780 char buf[10];
3781
3782 /* Turn the in/out constraint into an output constraint. */
3783 char *p = xstrdup (constraint);
3784 p[0] = '=';
3785 TREE_VALUE (TREE_PURPOSE (link)) = build_string (constraint_len, p);
3786
3787 /* And add a matching input constraint. */
3788 if (allows_reg)
3789 {
3790 sprintf (buf, "%d", i);
3791
3792 /* If there are multiple alternatives in the constraint,
3793 handle each of them individually. Those that allow register
3794 will be replaced with operand number, the others will stay
3795 unchanged. */
3796 if (strchr (p, ',') != NULL)
3797 {
3798 size_t len = 0, buflen = strlen (buf);
3799 char *beg, *end, *str, *dst;
3800
3801 for (beg = p + 1;;)
3802 {
3803 end = strchr (beg, ',');
3804 if (end == NULL)
3805 end = strchr (beg, '\0');
3806 if ((size_t) (end - beg) < buflen)
3807 len += buflen + 1;
3808 else
3809 len += end - beg + 1;
3810 if (*end)
3811 beg = end + 1;
3812 else
3813 break;
3814 }
3815
3816 str = (char *) alloca (len);
3817 for (beg = p + 1, dst = str;;)
3818 {
3819 const char *tem;
3820 bool mem_p, reg_p, inout_p;
3821
3822 end = strchr (beg, ',');
3823 if (end)
3824 *end = '\0';
3825 beg[-1] = '=';
3826 tem = beg - 1;
3827 parse_output_constraint (&tem, i, 0, 0,
3828 &mem_p, &reg_p, &inout_p);
3829 if (dst != str)
3830 *dst++ = ',';
3831 if (reg_p)
3832 {
3833 memcpy (dst, buf, buflen);
3834 dst += buflen;
3835 }
3836 else
3837 {
3838 if (end)
3839 len = end - beg;
3840 else
3841 len = strlen (beg);
3842 memcpy (dst, beg, len);
3843 dst += len;
3844 }
3845 if (end)
3846 beg = end + 1;
3847 else
3848 break;
3849 }
3850 *dst = '\0';
3851 input = build_string (dst - str, str);
3852 }
3853 else
3854 input = build_string (strlen (buf), buf);
3855 }
3856 else
3857 input = build_string (constraint_len - 1, constraint + 1);
3858
3859 free (p);
3860
3861 input = build_tree_list (build_tree_list (NULL_TREE, input),
3862 unshare_expr (TREE_VALUE (link)));
3863 ASM_INPUTS (expr) = chainon (ASM_INPUTS (expr), input);
3864 }
3865 }
3866
3867 for (link = ASM_INPUTS (expr); link; ++i, link = TREE_CHAIN (link))
3868 {
3869 constraint
3870 = TREE_STRING_POINTER (TREE_VALUE (TREE_PURPOSE (link)));
3871 parse_input_constraint (&constraint, 0, 0, noutputs, 0,
3872 oconstraints, &allows_mem, &allows_reg);
3873
3874 /* If the operand is a memory input, it should be an lvalue. */
3875 if (!allows_reg && allows_mem)
3876 {
3877 lang_hooks.mark_addressable (TREE_VALUE (link));
3878 tret = gimplify_expr (&TREE_VALUE (link), pre_p, post_p,
3879 is_gimple_lvalue, fb_lvalue | fb_mayfail);
3880 if (tret == GS_ERROR)
3881 {
3882 error ("memory input %d is not directly addressable", i);
3883 ret = tret;
3884 }
3885 }
3886 else
3887 {
3888 tret = gimplify_expr (&TREE_VALUE (link), pre_p, post_p,
3889 is_gimple_asm_val, fb_rvalue);
3890 if (tret == GS_ERROR)
3891 ret = tret;
3892 }
3893 }
3894
3895 return ret;
3896 }
3897
3898 /* Gimplify a CLEANUP_POINT_EXPR. Currently this works by adding
3899 WITH_CLEANUP_EXPRs to the prequeue as we encounter cleanups while
3900 gimplifying the body, and converting them to TRY_FINALLY_EXPRs when we
3901 return to this function.
3902
3903 FIXME should we complexify the prequeue handling instead? Or use flags
3904 for all the cleanups and let the optimizer tighten them up? The current
3905 code seems pretty fragile; it will break on a cleanup within any
3906 non-conditional nesting. But any such nesting would be broken, anyway;
3907 we can't write a TRY_FINALLY_EXPR that starts inside a nesting construct
3908 and continues out of it. We can do that at the RTL level, though, so
3909 having an optimizer to tighten up try/finally regions would be a Good
3910 Thing. */
3911
3912 static enum gimplify_status
3913 gimplify_cleanup_point_expr (tree *expr_p, tree *pre_p)
3914 {
3915 tree_stmt_iterator iter;
3916 tree body;
3917
3918 tree temp = voidify_wrapper_expr (*expr_p, NULL);
3919
3920 /* We only care about the number of conditions between the innermost
3921 CLEANUP_POINT_EXPR and the cleanup. So save and reset the count and
3922 any cleanups collected outside the CLEANUP_POINT_EXPR. */
3923 int old_conds = gimplify_ctxp->conditions;
3924 tree old_cleanups = gimplify_ctxp->conditional_cleanups;
3925 gimplify_ctxp->conditions = 0;
3926 gimplify_ctxp->conditional_cleanups = NULL_TREE;
3927
3928 body = TREE_OPERAND (*expr_p, 0);
3929 gimplify_to_stmt_list (&body);
3930
3931 gimplify_ctxp->conditions = old_conds;
3932 gimplify_ctxp->conditional_cleanups = old_cleanups;
3933
3934 for (iter = tsi_start (body); !tsi_end_p (iter); )
3935 {
3936 tree *wce_p = tsi_stmt_ptr (iter);
3937 tree wce = *wce_p;
3938
3939 if (TREE_CODE (wce) == WITH_CLEANUP_EXPR)
3940 {
3941 if (tsi_one_before_end_p (iter))
3942 {
3943 tsi_link_before (&iter, TREE_OPERAND (wce, 0), TSI_SAME_STMT);
3944 tsi_delink (&iter);
3945 break;
3946 }
3947 else
3948 {
3949 tree sl, tfe;
3950 enum tree_code code;
3951
3952 if (CLEANUP_EH_ONLY (wce))
3953 code = TRY_CATCH_EXPR;
3954 else
3955 code = TRY_FINALLY_EXPR;
3956
3957 sl = tsi_split_statement_list_after (&iter);
3958 tfe = build2 (code, void_type_node, sl, NULL_TREE);
3959 append_to_statement_list (TREE_OPERAND (wce, 0),
3960 &TREE_OPERAND (tfe, 1));
3961 *wce_p = tfe;
3962 iter = tsi_start (sl);
3963 }
3964 }
3965 else
3966 tsi_next (&iter);
3967 }
3968
3969 if (temp)
3970 {
3971 *expr_p = temp;
3972 append_to_statement_list (body, pre_p);
3973 return GS_OK;
3974 }
3975 else
3976 {
3977 *expr_p = body;
3978 return GS_ALL_DONE;
3979 }
3980 }
3981
3982 /* Insert a cleanup marker for gimplify_cleanup_point_expr. CLEANUP
3983 is the cleanup action required. */
3984
3985 static void
3986 gimple_push_cleanup (tree var, tree cleanup, bool eh_only, tree *pre_p)
3987 {
3988 tree wce;
3989
3990 /* Errors can result in improperly nested cleanups. Which results in
3991 confusion when trying to resolve the WITH_CLEANUP_EXPR. */
3992 if (errorcount || sorrycount)
3993 return;
3994
3995 if (gimple_conditional_context ())
3996 {
3997 /* If we're in a conditional context, this is more complex. We only
3998 want to run the cleanup if we actually ran the initialization that
3999 necessitates it, but we want to run it after the end of the
4000 conditional context. So we wrap the try/finally around the
4001 condition and use a flag to determine whether or not to actually
4002 run the destructor. Thus
4003
4004 test ? f(A()) : 0
4005
4006 becomes (approximately)
4007
4008 flag = 0;
4009 try {
4010 if (test) { A::A(temp); flag = 1; val = f(temp); }
4011 else { val = 0; }
4012 } finally {
4013 if (flag) A::~A(temp);
4014 }
4015 val
4016 */
4017
4018 tree flag = create_tmp_var (boolean_type_node, "cleanup");
4019 tree ffalse = build2 (MODIFY_EXPR, void_type_node, flag,
4020 boolean_false_node);
4021 tree ftrue = build2 (MODIFY_EXPR, void_type_node, flag,
4022 boolean_true_node);
4023 cleanup = build3 (COND_EXPR, void_type_node, flag, cleanup, NULL);
4024 wce = build1 (WITH_CLEANUP_EXPR, void_type_node, cleanup);
4025 append_to_statement_list (ffalse, &gimplify_ctxp->conditional_cleanups);
4026 append_to_statement_list (wce, &gimplify_ctxp->conditional_cleanups);
4027 append_to_statement_list (ftrue, pre_p);
4028
4029 /* Because of this manipulation, and the EH edges that jump
4030 threading cannot redirect, the temporary (VAR) will appear
4031 to be used uninitialized. Don't warn. */
4032 TREE_NO_WARNING (var) = 1;
4033 }
4034 else
4035 {
4036 wce = build1 (WITH_CLEANUP_EXPR, void_type_node, cleanup);
4037 CLEANUP_EH_ONLY (wce) = eh_only;
4038 append_to_statement_list (wce, pre_p);
4039 }
4040
4041 gimplify_stmt (&TREE_OPERAND (wce, 0));
4042 }
4043
4044 /* Gimplify a TARGET_EXPR which doesn't appear on the rhs of an INIT_EXPR. */
4045
4046 static enum gimplify_status
4047 gimplify_target_expr (tree *expr_p, tree *pre_p, tree *post_p)
4048 {
4049 tree targ = *expr_p;
4050 tree temp = TARGET_EXPR_SLOT (targ);
4051 tree init = TARGET_EXPR_INITIAL (targ);
4052 enum gimplify_status ret;
4053
4054 if (init)
4055 {
4056 /* Try to avoid the temporary if possible. */
4057 if (TREE_CODE (init) == INDIRECT_REF
4058 && !TREE_SIDE_EFFECTS (init)
4059 && !TARGET_EXPR_CLEANUP (targ))
4060 {
4061 *expr_p = init;
4062 return GS_OK;
4063 }
4064
4065 /* TARGET_EXPR temps aren't part of the enclosing block, so add it
4066 to the temps list. */
4067 gimple_add_tmp_var (temp);
4068
4069 /* If TARGET_EXPR_INITIAL is void, then the mere evaluation of the
4070 expression is supposed to initialize the slot. */
4071 if (VOID_TYPE_P (TREE_TYPE (init)))
4072 ret = gimplify_expr (&init, pre_p, post_p, is_gimple_stmt, fb_none);
4073 else
4074 {
4075 /* Special handling for BIND_EXPR can result in fewer temps. */
4076 ret = GS_OK;
4077 if (TREE_CODE (init) == BIND_EXPR)
4078 gimplify_bind_expr (&init, temp, pre_p);
4079 if (init != temp)
4080 {
4081 init = build2 (MODIFY_EXPR, void_type_node, temp, init);
4082 ret = gimplify_expr (&init, pre_p, post_p, is_gimple_stmt,
4083 fb_none);
4084 }
4085 }
4086 if (ret == GS_ERROR)
4087 return GS_ERROR;
4088 append_to_statement_list (init, pre_p);
4089
4090 /* If needed, push the cleanup for the temp. */
4091 if (TARGET_EXPR_CLEANUP (targ))
4092 {
4093 gimplify_stmt (&TARGET_EXPR_CLEANUP (targ));
4094 gimple_push_cleanup (temp, TARGET_EXPR_CLEANUP (targ),
4095 CLEANUP_EH_ONLY (targ), pre_p);
4096 }
4097
4098 /* Only expand this once. */
4099 TREE_OPERAND (targ, 3) = init;
4100 TARGET_EXPR_INITIAL (targ) = NULL_TREE;
4101 }
4102 else
4103 /* We should have expanded this before. */
4104 gcc_assert (DECL_SEEN_IN_BIND_EXPR_P (temp));
4105
4106 *expr_p = temp;
4107 return GS_OK;
4108 }
4109
4110 /* Gimplification of expression trees. */
4111
4112 /* Gimplify an expression which appears at statement context; usually, this
4113 means replacing it with a suitably gimple STATEMENT_LIST. */
4114
4115 void
4116 gimplify_stmt (tree *stmt_p)
4117 {
4118 gimplify_expr (stmt_p, NULL, NULL, is_gimple_stmt, fb_none);
4119 }
4120
4121 /* Similarly, but force the result to be a STATEMENT_LIST. */
4122
4123 void
4124 gimplify_to_stmt_list (tree *stmt_p)
4125 {
4126 gimplify_stmt (stmt_p);
4127 if (!*stmt_p)
4128 *stmt_p = alloc_stmt_list ();
4129 else if (TREE_CODE (*stmt_p) != STATEMENT_LIST)
4130 {
4131 tree t = *stmt_p;
4132 *stmt_p = alloc_stmt_list ();
4133 append_to_statement_list (t, stmt_p);
4134 }
4135 }
4136
4137
4138 /* Add FIRSTPRIVATE entries for DECL in the OpenMP the surrounding parallels
4139 to CTX. If entries already exist, force them to be some flavor of private.
4140 If there is no enclosing parallel, do nothing. */
4141
4142 void
4143 omp_firstprivatize_variable (struct gimplify_omp_ctx *ctx, tree decl)
4144 {
4145 splay_tree_node n;
4146
4147 if (decl == NULL || !DECL_P (decl))
4148 return;
4149
4150 do
4151 {
4152 n = splay_tree_lookup (ctx->variables, (splay_tree_key)decl);
4153 if (n != NULL)
4154 {
4155 if (n->value & GOVD_SHARED)
4156 n->value = GOVD_FIRSTPRIVATE | (n->value & GOVD_SEEN);
4157 else
4158 return;
4159 }
4160 else if (ctx->is_parallel)
4161 omp_add_variable (ctx, decl, GOVD_FIRSTPRIVATE);
4162
4163 ctx = ctx->outer_context;
4164 }
4165 while (ctx);
4166 }
4167
4168 /* Similarly for each of the type sizes of TYPE. */
4169
4170 static void
4171 omp_firstprivatize_type_sizes (struct gimplify_omp_ctx *ctx, tree type)
4172 {
4173 if (type == NULL || type == error_mark_node)
4174 return;
4175 type = TYPE_MAIN_VARIANT (type);
4176
4177 if (pointer_set_insert (ctx->privatized_types, type))
4178 return;
4179
4180 switch (TREE_CODE (type))
4181 {
4182 case INTEGER_TYPE:
4183 case ENUMERAL_TYPE:
4184 case BOOLEAN_TYPE:
4185 case CHAR_TYPE:
4186 case REAL_TYPE:
4187 omp_firstprivatize_variable (ctx, TYPE_MIN_VALUE (type));
4188 omp_firstprivatize_variable (ctx, TYPE_MAX_VALUE (type));
4189 break;
4190
4191 case ARRAY_TYPE:
4192 omp_firstprivatize_type_sizes (ctx, TREE_TYPE (type));
4193 omp_firstprivatize_type_sizes (ctx, TYPE_DOMAIN (type));
4194 break;
4195
4196 case RECORD_TYPE:
4197 case UNION_TYPE:
4198 case QUAL_UNION_TYPE:
4199 {
4200 tree field;
4201 for (field = TYPE_FIELDS (type); field; field = TREE_CHAIN (field))
4202 if (TREE_CODE (field) == FIELD_DECL)
4203 {
4204 omp_firstprivatize_variable (ctx, DECL_FIELD_OFFSET (field));
4205 omp_firstprivatize_type_sizes (ctx, TREE_TYPE (field));
4206 }
4207 }
4208 break;
4209
4210 case POINTER_TYPE:
4211 case REFERENCE_TYPE:
4212 omp_firstprivatize_type_sizes (ctx, TREE_TYPE (type));
4213 break;
4214
4215 default:
4216 break;
4217 }
4218
4219 omp_firstprivatize_variable (ctx, TYPE_SIZE (type));
4220 omp_firstprivatize_variable (ctx, TYPE_SIZE_UNIT (type));
4221 lang_hooks.types.omp_firstprivatize_type_sizes (ctx, type);
4222 }
4223
4224 /* Add an entry for DECL in the OpenMP context CTX with FLAGS. */
4225
4226 static void
4227 omp_add_variable (struct gimplify_omp_ctx *ctx, tree decl, unsigned int flags)
4228 {
4229 splay_tree_node n;
4230 unsigned int nflags;
4231 tree t;
4232
4233 if (decl == error_mark_node || TREE_TYPE (decl) == error_mark_node)
4234 return;
4235
4236 /* Never elide decls whose type has TREE_ADDRESSABLE set. This means
4237 there are constructors involved somewhere. */
4238 if (TREE_ADDRESSABLE (TREE_TYPE (decl))
4239 || TYPE_NEEDS_CONSTRUCTING (TREE_TYPE (decl)))
4240 flags |= GOVD_SEEN;
4241
4242 n = splay_tree_lookup (ctx->variables, (splay_tree_key)decl);
4243 if (n != NULL)
4244 {
4245 /* We shouldn't be re-adding the decl with the same data
4246 sharing class. */
4247 gcc_assert ((n->value & GOVD_DATA_SHARE_CLASS & flags) == 0);
4248 /* The only combination of data sharing classes we should see is
4249 FIRSTPRIVATE and LASTPRIVATE. */
4250 nflags = n->value | flags;
4251 gcc_assert ((nflags & GOVD_DATA_SHARE_CLASS)
4252 == (GOVD_FIRSTPRIVATE | GOVD_LASTPRIVATE));
4253 n->value = nflags;
4254 return;
4255 }
4256
4257 /* When adding a variable-sized variable, we have to handle all sorts
4258 of additional bits of data: the pointer replacement variable, and
4259 the parameters of the type. */
4260 if (!TREE_CONSTANT (DECL_SIZE (decl)))
4261 {
4262 /* Add the pointer replacement variable as PRIVATE if the variable
4263 replacement is private, else FIRSTPRIVATE since we'll need the
4264 address of the original variable either for SHARED, or for the
4265 copy into or out of the context. */
4266 if (!(flags & GOVD_LOCAL))
4267 {
4268 nflags = flags & GOVD_PRIVATE ? GOVD_PRIVATE : GOVD_FIRSTPRIVATE;
4269 nflags |= flags & GOVD_SEEN;
4270 t = DECL_VALUE_EXPR (decl);
4271 gcc_assert (TREE_CODE (t) == INDIRECT_REF);
4272 t = TREE_OPERAND (t, 0);
4273 gcc_assert (DECL_P (t));
4274 omp_add_variable (ctx, t, nflags);
4275 }
4276
4277 /* Add all of the variable and type parameters (which should have
4278 been gimplified to a formal temporary) as FIRSTPRIVATE. */
4279 omp_firstprivatize_variable (ctx, DECL_SIZE_UNIT (decl));
4280 omp_firstprivatize_variable (ctx, DECL_SIZE (decl));
4281 omp_firstprivatize_type_sizes (ctx, TREE_TYPE (decl));
4282
4283 /* The variable-sized variable itself is never SHARED, only some form
4284 of PRIVATE. The sharing would take place via the pointer variable
4285 which we remapped above. */
4286 if (flags & GOVD_SHARED)
4287 flags = GOVD_PRIVATE | GOVD_DEBUG_PRIVATE
4288 | (flags & (GOVD_SEEN | GOVD_EXPLICIT));
4289
4290 /* We're going to make use of the TYPE_SIZE_UNIT at least in the
4291 alloca statement we generate for the variable, so make sure it
4292 is available. This isn't automatically needed for the SHARED
4293 case, since we won't be allocating local storage then. */
4294 else
4295 omp_notice_variable (ctx, TYPE_SIZE_UNIT (TREE_TYPE (decl)), true);
4296 }
4297 else if (lang_hooks.decls.omp_privatize_by_reference (decl))
4298 {
4299 gcc_assert ((flags & GOVD_LOCAL) == 0);
4300 omp_firstprivatize_type_sizes (ctx, TREE_TYPE (decl));
4301
4302 /* Similar to the direct variable sized case above, we'll need the
4303 size of references being privatized. */
4304 if ((flags & GOVD_SHARED) == 0)
4305 {
4306 t = TYPE_SIZE_UNIT (TREE_TYPE (TREE_TYPE (decl)));
4307 if (!TREE_CONSTANT (t))
4308 omp_notice_variable (ctx, t, true);
4309 }
4310 }
4311
4312 splay_tree_insert (ctx->variables, (splay_tree_key)decl, flags);
4313 }
4314
4315 /* Record the fact that DECL was used within the OpenMP context CTX.
4316 IN_CODE is true when real code uses DECL, and false when we should
4317 merely emit default(none) errors. Return true if DECL is going to
4318 be remapped and thus DECL shouldn't be gimplified into its
4319 DECL_VALUE_EXPR (if any). */
4320
4321 static bool
4322 omp_notice_variable (struct gimplify_omp_ctx *ctx, tree decl, bool in_code)
4323 {
4324 splay_tree_node n;
4325 unsigned flags = in_code ? GOVD_SEEN : 0;
4326 bool ret = false, shared;
4327
4328 if (decl == error_mark_node || TREE_TYPE (decl) == error_mark_node)
4329 return false;
4330
4331 /* Threadprivate variables are predetermined. */
4332 if (is_global_var (decl))
4333 {
4334 if (DECL_THREAD_LOCAL_P (decl))
4335 return false;
4336
4337 if (DECL_HAS_VALUE_EXPR_P (decl))
4338 {
4339 tree value = get_base_address (DECL_VALUE_EXPR (decl));
4340
4341 if (value && DECL_P (value) && DECL_THREAD_LOCAL_P (value))
4342 return false;
4343 }
4344 }
4345
4346 n = splay_tree_lookup (ctx->variables, (splay_tree_key)decl);
4347 if (n == NULL)
4348 {
4349 enum omp_clause_default_kind default_kind, kind;
4350
4351 if (!ctx->is_parallel)
4352 goto do_outer;
4353
4354 /* ??? Some compiler-generated variables (like SAVE_EXPRs) could be
4355 remapped firstprivate instead of shared. To some extent this is
4356 addressed in omp_firstprivatize_type_sizes, but not effectively. */
4357 default_kind = ctx->default_kind;
4358 kind = lang_hooks.decls.omp_predetermined_sharing (decl);
4359 if (kind != OMP_CLAUSE_DEFAULT_UNSPECIFIED)
4360 default_kind = kind;
4361
4362 switch (default_kind)
4363 {
4364 case OMP_CLAUSE_DEFAULT_NONE:
4365 error ("%qs not specified in enclosing parallel",
4366 IDENTIFIER_POINTER (DECL_NAME (decl)));
4367 error ("%Henclosing parallel", &ctx->location);
4368 /* FALLTHRU */
4369 case OMP_CLAUSE_DEFAULT_SHARED:
4370 flags |= GOVD_SHARED;
4371 break;
4372 case OMP_CLAUSE_DEFAULT_PRIVATE:
4373 flags |= GOVD_PRIVATE;
4374 break;
4375 default:
4376 gcc_unreachable ();
4377 }
4378
4379 omp_add_variable (ctx, decl, flags);
4380
4381 shared = (flags & GOVD_SHARED) != 0;
4382 ret = lang_hooks.decls.omp_disregard_value_expr (decl, shared);
4383 goto do_outer;
4384 }
4385
4386 shared = ((flags | n->value) & GOVD_SHARED) != 0;
4387 ret = lang_hooks.decls.omp_disregard_value_expr (decl, shared);
4388
4389 /* If nothing changed, there's nothing left to do. */
4390 if ((n->value & flags) == flags)
4391 return ret;
4392 flags |= n->value;
4393 n->value = flags;
4394
4395 do_outer:
4396 /* If the variable is private in the current context, then we don't
4397 need to propagate anything to an outer context. */
4398 if (flags & GOVD_PRIVATE)
4399 return ret;
4400 if (ctx->outer_context
4401 && omp_notice_variable (ctx->outer_context, decl, in_code))
4402 return true;
4403 return ret;
4404 }
4405
4406 /* Verify that DECL is private within CTX. If there's specific information
4407 to the contrary in the innermost scope, generate an error. */
4408
4409 static bool
4410 omp_is_private (struct gimplify_omp_ctx *ctx, tree decl)
4411 {
4412 splay_tree_node n;
4413
4414 n = splay_tree_lookup (ctx->variables, (splay_tree_key)decl);
4415 if (n != NULL)
4416 {
4417 if (n->value & GOVD_SHARED)
4418 {
4419 if (ctx == gimplify_omp_ctxp)
4420 error ("iteration variable %qs should be private",
4421 IDENTIFIER_POINTER (DECL_NAME (decl)));
4422 n->value = GOVD_PRIVATE;
4423 }
4424 return true;
4425 }
4426
4427 if (ctx->outer_context)
4428 return omp_is_private (ctx->outer_context, decl);
4429 else if (ctx->is_parallel)
4430 return false;
4431 else
4432 return !is_global_var (decl);
4433 }
4434
4435 /* Scan the OpenMP clauses in *LIST_P, installing mappings into a new
4436 and previous omp contexts. */
4437
4438 static void
4439 gimplify_scan_omp_clauses (tree *list_p, tree *pre_p, bool in_parallel)
4440 {
4441 struct gimplify_omp_ctx *ctx, *outer_ctx;
4442 tree c;
4443
4444 ctx = new_omp_context (in_parallel);
4445 outer_ctx = ctx->outer_context;
4446
4447 while ((c = *list_p) != NULL)
4448 {
4449 enum gimplify_status gs;
4450 bool remove = false;
4451 bool notice_outer = true;
4452 unsigned int flags;
4453 tree decl;
4454
4455 switch (OMP_CLAUSE_CODE (c))
4456 {
4457 case OMP_CLAUSE_PRIVATE:
4458 flags = GOVD_PRIVATE | GOVD_EXPLICIT;
4459 notice_outer = false;
4460 goto do_add;
4461 case OMP_CLAUSE_SHARED:
4462 flags = GOVD_SHARED | GOVD_EXPLICIT;
4463 goto do_add;
4464 case OMP_CLAUSE_FIRSTPRIVATE:
4465 flags = GOVD_FIRSTPRIVATE | GOVD_EXPLICIT;
4466 goto do_add;
4467 case OMP_CLAUSE_LASTPRIVATE:
4468 flags = GOVD_LASTPRIVATE | GOVD_SEEN | GOVD_EXPLICIT;
4469 goto do_add;
4470 case OMP_CLAUSE_REDUCTION:
4471 flags = GOVD_REDUCTION | GOVD_SEEN | GOVD_EXPLICIT;
4472 goto do_add;
4473
4474 do_add:
4475 decl = OMP_CLAUSE_DECL (c);
4476 if (decl == error_mark_node || TREE_TYPE (decl) == error_mark_node)
4477 {
4478 remove = true;
4479 break;
4480 }
4481 omp_add_variable (ctx, decl, flags);
4482 if (TREE_CODE (c) == OMP_CLAUSE_REDUCTION
4483 && OMP_CLAUSE_REDUCTION_PLACEHOLDER (c))
4484 {
4485 omp_add_variable (ctx, OMP_CLAUSE_REDUCTION_PLACEHOLDER (c),
4486 GOVD_LOCAL);
4487 gimplify_omp_ctxp = ctx;
4488 push_gimplify_context ();
4489 gimplify_stmt (&OMP_CLAUSE_REDUCTION_INIT (c));
4490 pop_gimplify_context (OMP_CLAUSE_REDUCTION_INIT (c));
4491 push_gimplify_context ();
4492 gimplify_stmt (&OMP_CLAUSE_REDUCTION_MERGE (c));
4493 pop_gimplify_context (OMP_CLAUSE_REDUCTION_MERGE (c));
4494 gimplify_omp_ctxp = outer_ctx;
4495 }
4496 if (notice_outer)
4497 goto do_notice;
4498 break;
4499
4500 case OMP_CLAUSE_COPYIN:
4501 case OMP_CLAUSE_COPYPRIVATE:
4502 decl = OMP_CLAUSE_DECL (c);
4503 if (decl == error_mark_node || TREE_TYPE (decl) == error_mark_node)
4504 {
4505 remove = true;
4506 break;
4507 }
4508 do_notice:
4509 if (outer_ctx)
4510 omp_notice_variable (outer_ctx, decl, true);
4511 break;
4512
4513 case OMP_CLAUSE_SCHEDULE:
4514 case OMP_CLAUSE_IF:
4515 case OMP_CLAUSE_NUM_THREADS:
4516 gs = gimplify_expr (&OMP_CLAUSE_OPERAND (c, 0), pre_p, NULL,
4517 is_gimple_val, fb_rvalue);
4518 if (gs == GS_ERROR)
4519 remove = true;
4520 break;
4521
4522 case OMP_CLAUSE_NOWAIT:
4523 case OMP_CLAUSE_ORDERED:
4524 break;
4525
4526 case OMP_CLAUSE_DEFAULT:
4527 ctx->default_kind = OMP_CLAUSE_DEFAULT_KIND (c);
4528 break;
4529
4530 default:
4531 gcc_unreachable ();
4532 }
4533
4534 if (remove)
4535 *list_p = OMP_CLAUSE_CHAIN (c);
4536 else
4537 list_p = &OMP_CLAUSE_CHAIN (c);
4538 }
4539
4540 gimplify_omp_ctxp = ctx;
4541 }
4542
4543 /* For all variables that were not actually used within the context,
4544 remove PRIVATE, SHARED, and FIRSTPRIVATE clauses. */
4545
4546 static int
4547 gimplify_adjust_omp_clauses_1 (splay_tree_node n, void *data)
4548 {
4549 tree *list_p = (tree *) data;
4550 tree decl = (tree) n->key;
4551 unsigned flags = n->value;
4552 enum omp_clause_code code;
4553 tree clause;
4554 bool private_debug;
4555
4556 if (flags & (GOVD_EXPLICIT | GOVD_LOCAL))
4557 return 0;
4558 if ((flags & GOVD_SEEN) == 0)
4559 return 0;
4560 if (flags & GOVD_DEBUG_PRIVATE)
4561 {
4562 gcc_assert ((flags & GOVD_DATA_SHARE_CLASS) == GOVD_PRIVATE);
4563 private_debug = true;
4564 }
4565 else
4566 private_debug
4567 = lang_hooks.decls.omp_private_debug_clause (decl,
4568 !!(flags & GOVD_SHARED));
4569 if (private_debug)
4570 code = OMP_CLAUSE_PRIVATE;
4571 else if (flags & GOVD_SHARED)
4572 {
4573 if (is_global_var (decl))
4574 return 0;
4575 code = OMP_CLAUSE_SHARED;
4576 }
4577 else if (flags & GOVD_PRIVATE)
4578 code = OMP_CLAUSE_PRIVATE;
4579 else if (flags & GOVD_FIRSTPRIVATE)
4580 code = OMP_CLAUSE_FIRSTPRIVATE;
4581 else
4582 gcc_unreachable ();
4583
4584 clause = build_omp_clause (code);
4585 OMP_CLAUSE_DECL (clause) = decl;
4586 OMP_CLAUSE_CHAIN (clause) = *list_p;
4587 if (private_debug)
4588 OMP_CLAUSE_PRIVATE_DEBUG (clause) = 1;
4589 *list_p = clause;
4590
4591 return 0;
4592 }
4593
4594 static void
4595 gimplify_adjust_omp_clauses (tree *list_p)
4596 {
4597 struct gimplify_omp_ctx *ctx = gimplify_omp_ctxp;
4598 tree c, decl;
4599
4600 while ((c = *list_p) != NULL)
4601 {
4602 splay_tree_node n;
4603 bool remove = false;
4604
4605 switch (OMP_CLAUSE_CODE (c))
4606 {
4607 case OMP_CLAUSE_PRIVATE:
4608 case OMP_CLAUSE_SHARED:
4609 case OMP_CLAUSE_FIRSTPRIVATE:
4610 decl = OMP_CLAUSE_DECL (c);
4611 n = splay_tree_lookup (ctx->variables, (splay_tree_key) decl);
4612 remove = !(n->value & GOVD_SEEN);
4613 if (! remove)
4614 {
4615 bool shared = OMP_CLAUSE_CODE (c) == OMP_CLAUSE_SHARED;
4616 if ((n->value & GOVD_DEBUG_PRIVATE)
4617 || lang_hooks.decls.omp_private_debug_clause (decl, shared))
4618 {
4619 gcc_assert ((n->value & GOVD_DEBUG_PRIVATE) == 0
4620 || ((n->value & GOVD_DATA_SHARE_CLASS)
4621 == GOVD_PRIVATE));
4622 OMP_CLAUSE_SET_CODE (c, OMP_CLAUSE_PRIVATE);
4623 OMP_CLAUSE_PRIVATE_DEBUG (c) = 1;
4624 }
4625 }
4626 break;
4627
4628 case OMP_CLAUSE_LASTPRIVATE:
4629 /* Make sure OMP_CLAUSE_LASTPRIVATE_FIRSTPRIVATE is set to
4630 accurately reflect the presence of a FIRSTPRIVATE clause. */
4631 decl = OMP_CLAUSE_DECL (c);
4632 n = splay_tree_lookup (ctx->variables, (splay_tree_key) decl);
4633 OMP_CLAUSE_LASTPRIVATE_FIRSTPRIVATE (c)
4634 = (n->value & GOVD_FIRSTPRIVATE) != 0;
4635 break;
4636
4637 case OMP_CLAUSE_REDUCTION:
4638 case OMP_CLAUSE_COPYIN:
4639 case OMP_CLAUSE_COPYPRIVATE:
4640 case OMP_CLAUSE_IF:
4641 case OMP_CLAUSE_NUM_THREADS:
4642 case OMP_CLAUSE_SCHEDULE:
4643 case OMP_CLAUSE_NOWAIT:
4644 case OMP_CLAUSE_ORDERED:
4645 case OMP_CLAUSE_DEFAULT:
4646 break;
4647
4648 default:
4649 gcc_unreachable ();
4650 }
4651
4652 if (remove)
4653 *list_p = OMP_CLAUSE_CHAIN (c);
4654 else
4655 list_p = &OMP_CLAUSE_CHAIN (c);
4656 }
4657
4658 /* Add in any implicit data sharing. */
4659 splay_tree_foreach (ctx->variables, gimplify_adjust_omp_clauses_1, list_p);
4660
4661 gimplify_omp_ctxp = ctx->outer_context;
4662 delete_omp_context (ctx);
4663 }
4664
4665 /* Gimplify the contents of an OMP_PARALLEL statement. This involves
4666 gimplification of the body, as well as scanning the body for used
4667 variables. We need to do this scan now, because variable-sized
4668 decls will be decomposed during gimplification. */
4669
4670 static enum gimplify_status
4671 gimplify_omp_parallel (tree *expr_p, tree *pre_p)
4672 {
4673 tree expr = *expr_p;
4674
4675 gimplify_scan_omp_clauses (&OMP_PARALLEL_CLAUSES (expr), pre_p, true);
4676
4677 push_gimplify_context ();
4678
4679 gimplify_stmt (&OMP_PARALLEL_BODY (expr));
4680
4681 if (TREE_CODE (OMP_PARALLEL_BODY (expr)) == BIND_EXPR)
4682 pop_gimplify_context (OMP_PARALLEL_BODY (expr));
4683 else
4684 pop_gimplify_context (NULL_TREE);
4685
4686 gimplify_adjust_omp_clauses (&OMP_PARALLEL_CLAUSES (expr));
4687
4688 return GS_ALL_DONE;
4689 }
4690
4691 /* Gimplify the gross structure of an OMP_FOR statement. */
4692
4693 static enum gimplify_status
4694 gimplify_omp_for (tree *expr_p, tree *pre_p)
4695 {
4696 tree for_stmt, decl, t;
4697 enum gimplify_status ret = 0;
4698
4699 for_stmt = *expr_p;
4700
4701 gimplify_scan_omp_clauses (&OMP_FOR_CLAUSES (for_stmt), pre_p, false);
4702
4703 t = OMP_FOR_INIT (for_stmt);
4704 gcc_assert (TREE_CODE (t) == MODIFY_EXPR);
4705 decl = TREE_OPERAND (t, 0);
4706 gcc_assert (DECL_P (decl));
4707 gcc_assert (INTEGRAL_TYPE_P (TREE_TYPE (decl)));
4708 gcc_assert (!TYPE_UNSIGNED (TREE_TYPE (decl)));
4709
4710 /* Make sure the iteration variable is private. */
4711 if (omp_is_private (gimplify_omp_ctxp, decl))
4712 omp_notice_variable (gimplify_omp_ctxp, decl, true);
4713 else
4714 omp_add_variable (gimplify_omp_ctxp, decl, GOVD_PRIVATE | GOVD_SEEN);
4715
4716 ret |= gimplify_expr (&TREE_OPERAND (t, 1), &OMP_FOR_PRE_BODY (for_stmt),
4717 NULL, is_gimple_val, fb_rvalue);
4718
4719 t = OMP_FOR_COND (for_stmt);
4720 gcc_assert (COMPARISON_CLASS_P (t));
4721 gcc_assert (TREE_OPERAND (t, 0) == decl);
4722
4723 ret |= gimplify_expr (&TREE_OPERAND (t, 1), &OMP_FOR_PRE_BODY (for_stmt),
4724 NULL, is_gimple_val, fb_rvalue);
4725
4726 t = OMP_FOR_INCR (for_stmt);
4727 switch (TREE_CODE (t))
4728 {
4729 case PREINCREMENT_EXPR:
4730 case POSTINCREMENT_EXPR:
4731 t = build_int_cst (TREE_TYPE (decl), 1);
4732 goto build_modify;
4733 case PREDECREMENT_EXPR:
4734 case POSTDECREMENT_EXPR:
4735 t = build_int_cst (TREE_TYPE (decl), -1);
4736 goto build_modify;
4737 build_modify:
4738 t = build2 (PLUS_EXPR, TREE_TYPE (decl), decl, t);
4739 t = build2 (MODIFY_EXPR, void_type_node, decl, t);
4740 OMP_FOR_INCR (for_stmt) = t;
4741 break;
4742
4743 case MODIFY_EXPR:
4744 gcc_assert (TREE_OPERAND (t, 0) == decl);
4745 t = TREE_OPERAND (t, 1);
4746 switch (TREE_CODE (t))
4747 {
4748 case PLUS_EXPR:
4749 if (TREE_OPERAND (t, 1) == decl)
4750 {
4751 TREE_OPERAND (t, 1) = TREE_OPERAND (t, 0);
4752 TREE_OPERAND (t, 0) = decl;
4753 break;
4754 }
4755 case MINUS_EXPR:
4756 gcc_assert (TREE_OPERAND (t, 0) == decl);
4757 break;
4758 default:
4759 gcc_unreachable ();
4760 }
4761
4762 ret |= gimplify_expr (&TREE_OPERAND (t, 1), &OMP_FOR_PRE_BODY (for_stmt),
4763 NULL, is_gimple_val, fb_rvalue);
4764 break;
4765
4766 default:
4767 gcc_unreachable ();
4768 }
4769
4770 gimplify_to_stmt_list (&OMP_FOR_BODY (for_stmt));
4771 gimplify_adjust_omp_clauses (&OMP_FOR_CLAUSES (for_stmt));
4772
4773 return ret == GS_ALL_DONE ? GS_ALL_DONE : GS_ERROR;
4774 }
4775
4776 /* Gimplify the gross structure of other OpenMP worksharing constructs.
4777 In particular, OMP_SECTIONS and OMP_SINGLE. */
4778
4779 static enum gimplify_status
4780 gimplify_omp_workshare (tree *expr_p, tree *pre_p)
4781 {
4782 tree stmt = *expr_p;
4783
4784 gimplify_scan_omp_clauses (&OMP_CLAUSES (stmt), pre_p, false);
4785 gimplify_to_stmt_list (&OMP_BODY (stmt));
4786 gimplify_adjust_omp_clauses (&OMP_CLAUSES (stmt));
4787
4788 return GS_ALL_DONE;
4789 }
4790
4791 /* A subroutine of gimplify_omp_atomic. The front end is supposed to have
4792 stabilized the lhs of the atomic operation as *ADDR. Return true if
4793 EXPR is this stabilized form. */
4794
4795 static bool
4796 goa_lhs_expr_p (tree expr, tree addr)
4797 {
4798 /* Also include casts to other type variants. The C front end is fond
4799 of adding these for e.g. volatile variables. This is like
4800 STRIP_TYPE_NOPS but includes the main variant lookup. */
4801 while ((TREE_CODE (expr) == NOP_EXPR
4802 || TREE_CODE (expr) == CONVERT_EXPR
4803 || TREE_CODE (expr) == NON_LVALUE_EXPR)
4804 && TREE_OPERAND (expr, 0) != error_mark_node
4805 && (TYPE_MAIN_VARIANT (TREE_TYPE (expr))
4806 == TYPE_MAIN_VARIANT (TREE_TYPE (TREE_OPERAND (expr, 0)))))
4807 expr = TREE_OPERAND (expr, 0);
4808
4809 if (TREE_CODE (expr) == INDIRECT_REF && TREE_OPERAND (expr, 0) == addr)
4810 return true;
4811 if (TREE_CODE (addr) == ADDR_EXPR && expr == TREE_OPERAND (addr, 0))
4812 return true;
4813 return false;
4814 }
4815
4816 /* A subroutine of gimplify_omp_atomic. Attempt to implement the atomic
4817 operation as a __sync_fetch_and_op builtin. INDEX is log2 of the
4818 size of the data type, and thus usable to find the index of the builtin
4819 decl. Returns GS_UNHANDLED if the expression is not of the proper form. */
4820
4821 static enum gimplify_status
4822 gimplify_omp_atomic_fetch_op (tree *expr_p, tree addr, tree rhs, int index)
4823 {
4824 enum built_in_function base;
4825 tree decl, args, itype;
4826 enum insn_code *optab;
4827
4828 /* Check for one of the supported fetch-op operations. */
4829 switch (TREE_CODE (rhs))
4830 {
4831 case PLUS_EXPR:
4832 base = BUILT_IN_FETCH_AND_ADD_N;
4833 optab = sync_add_optab;
4834 break;
4835 case MINUS_EXPR:
4836 base = BUILT_IN_FETCH_AND_SUB_N;
4837 optab = sync_add_optab;
4838 break;
4839 case BIT_AND_EXPR:
4840 base = BUILT_IN_FETCH_AND_AND_N;
4841 optab = sync_and_optab;
4842 break;
4843 case BIT_IOR_EXPR:
4844 base = BUILT_IN_FETCH_AND_OR_N;
4845 optab = sync_ior_optab;
4846 break;
4847 case BIT_XOR_EXPR:
4848 base = BUILT_IN_FETCH_AND_XOR_N;
4849 optab = sync_xor_optab;
4850 break;
4851 default:
4852 return GS_UNHANDLED;
4853 }
4854
4855 /* Make sure the expression is of the proper form. */
4856 if (goa_lhs_expr_p (TREE_OPERAND (rhs, 0), addr))
4857 rhs = TREE_OPERAND (rhs, 1);
4858 else if (commutative_tree_code (TREE_CODE (rhs))
4859 && goa_lhs_expr_p (TREE_OPERAND (rhs, 1), addr))
4860 rhs = TREE_OPERAND (rhs, 0);
4861 else
4862 return GS_UNHANDLED;
4863
4864 decl = built_in_decls[base + index + 1];
4865 itype = TREE_TYPE (TREE_TYPE (decl));
4866
4867 if (optab[TYPE_MODE (itype)] == CODE_FOR_nothing)
4868 return GS_UNHANDLED;
4869
4870 args = tree_cons (NULL, fold_convert (itype, rhs), NULL);
4871 args = tree_cons (NULL, addr, args);
4872 *expr_p = build_function_call_expr (decl, args);
4873 return GS_OK;
4874 }
4875
4876 /* A subroutine of gimplify_omp_atomic_pipeline. Walk *EXPR_P and replace
4877 appearences of *LHS_ADDR with LHS_VAR. If an expression does not involve
4878 the lhs, evaluate it into a temporary. Return 1 if the lhs appeared as
4879 a subexpression, 0 if it did not, or -1 if an error was encountered. */
4880
4881 static int
4882 goa_stabilize_expr (tree *expr_p, tree *pre_p, tree lhs_addr, tree lhs_var)
4883 {
4884 tree expr = *expr_p;
4885 int saw_lhs;
4886
4887 if (goa_lhs_expr_p (expr, lhs_addr))
4888 {
4889 *expr_p = lhs_var;
4890 return 1;
4891 }
4892 if (is_gimple_val (expr))
4893 return 0;
4894
4895 saw_lhs = 0;
4896 switch (TREE_CODE_CLASS (TREE_CODE (expr)))
4897 {
4898 case tcc_binary:
4899 saw_lhs |= goa_stabilize_expr (&TREE_OPERAND (expr, 1), pre_p,
4900 lhs_addr, lhs_var);
4901 case tcc_unary:
4902 saw_lhs |= goa_stabilize_expr (&TREE_OPERAND (expr, 0), pre_p,
4903 lhs_addr, lhs_var);
4904 break;
4905 default:
4906 break;
4907 }
4908
4909 if (saw_lhs == 0)
4910 {
4911 enum gimplify_status gs;
4912 gs = gimplify_expr (expr_p, pre_p, NULL, is_gimple_val, fb_rvalue);
4913 if (gs != GS_ALL_DONE)
4914 saw_lhs = -1;
4915 }
4916
4917 return saw_lhs;
4918 }
4919
4920 /* A subroutine of gimplify_omp_atomic. Implement the atomic operation as:
4921
4922 oldval = *addr;
4923 repeat:
4924 newval = rhs; // with oldval replacing *addr in rhs
4925 oldval = __sync_val_compare_and_swap (addr, oldval, newval);
4926 if (oldval != newval)
4927 goto repeat;
4928
4929 INDEX is log2 of the size of the data type, and thus usable to find the
4930 index of the builtin decl. */
4931
4932 static enum gimplify_status
4933 gimplify_omp_atomic_pipeline (tree *expr_p, tree *pre_p, tree addr,
4934 tree rhs, int index)
4935 {
4936 tree oldval, oldival, oldival2, newval, newival, label;
4937 tree type, itype, cmpxchg, args, x, iaddr;
4938
4939 cmpxchg = built_in_decls[BUILT_IN_VAL_COMPARE_AND_SWAP_N + index + 1];
4940 type = TYPE_MAIN_VARIANT (TREE_TYPE (TREE_TYPE (addr)));
4941 itype = TREE_TYPE (TREE_TYPE (cmpxchg));
4942
4943 if (sync_compare_and_swap[TYPE_MODE (itype)] == CODE_FOR_nothing)
4944 return GS_UNHANDLED;
4945
4946 oldval = create_tmp_var (type, NULL);
4947 newval = create_tmp_var (type, NULL);
4948
4949 /* Precompute as much of RHS as possible. In the same walk, replace
4950 occurrences of the lhs value with our temporary. */
4951 if (goa_stabilize_expr (&rhs, pre_p, addr, oldval) < 0)
4952 return GS_ERROR;
4953
4954 x = build_fold_indirect_ref (addr);
4955 x = build2 (MODIFY_EXPR, void_type_node, oldval, x);
4956 gimplify_and_add (x, pre_p);
4957
4958 /* For floating-point values, we'll need to view-convert them to integers
4959 so that we can perform the atomic compare and swap. Simplify the
4960 following code by always setting up the "i"ntegral variables. */
4961 if (INTEGRAL_TYPE_P (type) || POINTER_TYPE_P (type))
4962 {
4963 oldival = oldval;
4964 newival = newval;
4965 iaddr = addr;
4966 }
4967 else
4968 {
4969 oldival = create_tmp_var (itype, NULL);
4970 newival = create_tmp_var (itype, NULL);
4971
4972 x = build1 (VIEW_CONVERT_EXPR, itype, oldval);
4973 x = build2 (MODIFY_EXPR, void_type_node, oldival, x);
4974 gimplify_and_add (x, pre_p);
4975 iaddr = fold_convert (build_pointer_type (itype), addr);
4976 }
4977
4978 oldival2 = create_tmp_var (itype, NULL);
4979
4980 label = create_artificial_label ();
4981 x = build1 (LABEL_EXPR, void_type_node, label);
4982 gimplify_and_add (x, pre_p);
4983
4984 x = build2 (MODIFY_EXPR, void_type_node, newval, rhs);
4985 gimplify_and_add (x, pre_p);
4986
4987 if (newval != newival)
4988 {
4989 x = build1 (VIEW_CONVERT_EXPR, itype, newval);
4990 x = build2 (MODIFY_EXPR, void_type_node, newival, x);
4991 gimplify_and_add (x, pre_p);
4992 }
4993
4994 x = build2 (MODIFY_EXPR, void_type_node, oldival2, oldival);
4995 gimplify_and_add (x, pre_p);
4996
4997 args = tree_cons (NULL, fold_convert (itype, newival), NULL);
4998 args = tree_cons (NULL, fold_convert (itype, oldival), args);
4999 args = tree_cons (NULL, iaddr, args);
5000 x = build_function_call_expr (cmpxchg, args);
5001 if (oldval == oldival)
5002 x = fold_convert (type, x);
5003 x = build2 (MODIFY_EXPR, void_type_node, oldival, x);
5004 gimplify_and_add (x, pre_p);
5005
5006 /* For floating point, be prepared for the loop backedge. */
5007 if (oldval != oldival)
5008 {
5009 x = build1 (VIEW_CONVERT_EXPR, type, oldival);
5010 x = build2 (MODIFY_EXPR, void_type_node, oldval, x);
5011 gimplify_and_add (x, pre_p);
5012 }
5013
5014 /* Note that we always perform the comparison as an integer, even for
5015 floating point. This allows the atomic operation to properly
5016 succeed even with NaNs and -0.0. */
5017 x = build3 (COND_EXPR, void_type_node,
5018 build2 (NE_EXPR, boolean_type_node, oldival, oldival2),
5019 build1 (GOTO_EXPR, void_type_node, label), NULL);
5020 gimplify_and_add (x, pre_p);
5021
5022 *expr_p = NULL;
5023 return GS_ALL_DONE;
5024 }
5025
5026 /* A subroutine of gimplify_omp_atomic. Implement the atomic operation as:
5027
5028 GOMP_atomic_start ();
5029 *addr = rhs;
5030 GOMP_atomic_end ();
5031
5032 The result is not globally atomic, but works so long as all parallel
5033 references are within #pragma omp atomic directives. According to
5034 responses received from omp@openmp.org, appears to be within spec.
5035 Which makes sense, since that's how several other compilers handle
5036 this situation as well. */
5037
5038 static enum gimplify_status
5039 gimplify_omp_atomic_mutex (tree *expr_p, tree *pre_p, tree addr, tree rhs)
5040 {
5041 tree t;
5042
5043 t = built_in_decls[BUILT_IN_GOMP_ATOMIC_START];
5044 t = build_function_call_expr (t, NULL);
5045 gimplify_and_add (t, pre_p);
5046
5047 t = build_fold_indirect_ref (addr);
5048 t = build2 (MODIFY_EXPR, void_type_node, t, rhs);
5049 gimplify_and_add (t, pre_p);
5050
5051 t = built_in_decls[BUILT_IN_GOMP_ATOMIC_END];
5052 t = build_function_call_expr (t, NULL);
5053 gimplify_and_add (t, pre_p);
5054
5055 *expr_p = NULL;
5056 return GS_ALL_DONE;
5057 }
5058
5059 /* Gimplify an OMP_ATOMIC statement. */
5060
5061 static enum gimplify_status
5062 gimplify_omp_atomic (tree *expr_p, tree *pre_p)
5063 {
5064 tree addr = TREE_OPERAND (*expr_p, 0);
5065 tree rhs = TREE_OPERAND (*expr_p, 1);
5066 tree type = TYPE_MAIN_VARIANT (TREE_TYPE (TREE_TYPE (addr)));
5067 HOST_WIDE_INT index;
5068
5069 /* Make sure the type is one of the supported sizes. */
5070 index = tree_low_cst (TYPE_SIZE_UNIT (type), 1);
5071 index = exact_log2 (index);
5072 if (index >= 0 && index <= 4)
5073 {
5074 enum gimplify_status gs;
5075 unsigned int align;
5076
5077 if (DECL_P (TREE_OPERAND (addr, 0)))
5078 align = DECL_ALIGN_UNIT (TREE_OPERAND (addr, 0));
5079 else if (TREE_CODE (TREE_OPERAND (addr, 0)) == COMPONENT_REF
5080 && TREE_CODE (TREE_OPERAND (TREE_OPERAND (addr, 0), 1))
5081 == FIELD_DECL)
5082 align = DECL_ALIGN_UNIT (TREE_OPERAND (TREE_OPERAND (addr, 0), 1));
5083 else
5084 align = TYPE_ALIGN_UNIT (type);
5085
5086 /* __sync builtins require strict data alignment. */
5087 if (exact_log2 (align) >= index)
5088 {
5089 /* When possible, use specialized atomic update functions. */
5090 if (INTEGRAL_TYPE_P (type) || POINTER_TYPE_P (type))
5091 {
5092 gs = gimplify_omp_atomic_fetch_op (expr_p, addr, rhs, index);
5093 if (gs != GS_UNHANDLED)
5094 return gs;
5095 }
5096
5097 /* If we don't have specialized __sync builtins, try and implement
5098 as a compare and swap loop. */
5099 gs = gimplify_omp_atomic_pipeline (expr_p, pre_p, addr, rhs, index);
5100 if (gs != GS_UNHANDLED)
5101 return gs;
5102 }
5103 }
5104
5105 /* The ultimate fallback is wrapping the operation in a mutex. */
5106 return gimplify_omp_atomic_mutex (expr_p, pre_p, addr, rhs);
5107 }
5108
5109 /* Gimplifies the expression tree pointed to by EXPR_P. Return 0 if
5110 gimplification failed.
5111
5112 PRE_P points to the list where side effects that must happen before
5113 EXPR should be stored.
5114
5115 POST_P points to the list where side effects that must happen after
5116 EXPR should be stored, or NULL if there is no suitable list. In
5117 that case, we copy the result to a temporary, emit the
5118 post-effects, and then return the temporary.
5119
5120 GIMPLE_TEST_F points to a function that takes a tree T and
5121 returns nonzero if T is in the GIMPLE form requested by the
5122 caller. The GIMPLE predicates are in tree-gimple.c.
5123
5124 This test is used twice. Before gimplification, the test is
5125 invoked to determine whether *EXPR_P is already gimple enough. If
5126 that fails, *EXPR_P is gimplified according to its code and
5127 GIMPLE_TEST_F is called again. If the test still fails, then a new
5128 temporary variable is created and assigned the value of the
5129 gimplified expression.
5130
5131 FALLBACK tells the function what sort of a temporary we want. If the 1
5132 bit is set, an rvalue is OK. If the 2 bit is set, an lvalue is OK.
5133 If both are set, either is OK, but an lvalue is preferable.
5134
5135 The return value is either GS_ERROR or GS_ALL_DONE, since this function
5136 iterates until solution. */
5137
5138 enum gimplify_status
5139 gimplify_expr (tree *expr_p, tree *pre_p, tree *post_p,
5140 bool (* gimple_test_f) (tree), fallback_t fallback)
5141 {
5142 tree tmp;
5143 tree internal_pre = NULL_TREE;
5144 tree internal_post = NULL_TREE;
5145 tree save_expr;
5146 int is_statement = (pre_p == NULL);
5147 location_t saved_location;
5148 enum gimplify_status ret;
5149
5150 save_expr = *expr_p;
5151 if (save_expr == NULL_TREE)
5152 return GS_ALL_DONE;
5153
5154 /* We used to check the predicate here and return immediately if it
5155 succeeds. This is wrong; the design is for gimplification to be
5156 idempotent, and for the predicates to only test for valid forms, not
5157 whether they are fully simplified. */
5158
5159 /* Set up our internal queues if needed. */
5160 if (pre_p == NULL)
5161 pre_p = &internal_pre;
5162 if (post_p == NULL)
5163 post_p = &internal_post;
5164
5165 saved_location = input_location;
5166 if (save_expr != error_mark_node
5167 && EXPR_HAS_LOCATION (*expr_p))
5168 input_location = EXPR_LOCATION (*expr_p);
5169
5170 /* Loop over the specific gimplifiers until the toplevel node
5171 remains the same. */
5172 do
5173 {
5174 /* Strip away as many useless type conversions as possible
5175 at the toplevel. */
5176 STRIP_USELESS_TYPE_CONVERSION (*expr_p);
5177
5178 /* Remember the expr. */
5179 save_expr = *expr_p;
5180
5181 /* Die, die, die, my darling. */
5182 if (save_expr == error_mark_node
5183 || (TREE_TYPE (save_expr)
5184 && TREE_TYPE (save_expr) == error_mark_node))
5185 {
5186 ret = GS_ERROR;
5187 break;
5188 }
5189
5190 /* Do any language-specific gimplification. */
5191 ret = lang_hooks.gimplify_expr (expr_p, pre_p, post_p);
5192 if (ret == GS_OK)
5193 {
5194 if (*expr_p == NULL_TREE)
5195 break;
5196 if (*expr_p != save_expr)
5197 continue;
5198 }
5199 else if (ret != GS_UNHANDLED)
5200 break;
5201
5202 ret = GS_OK;
5203 switch (TREE_CODE (*expr_p))
5204 {
5205 /* First deal with the special cases. */
5206
5207 case POSTINCREMENT_EXPR:
5208 case POSTDECREMENT_EXPR:
5209 case PREINCREMENT_EXPR:
5210 case PREDECREMENT_EXPR:
5211 ret = gimplify_self_mod_expr (expr_p, pre_p, post_p,
5212 fallback != fb_none);
5213 break;
5214
5215 case ARRAY_REF:
5216 case ARRAY_RANGE_REF:
5217 case REALPART_EXPR:
5218 case IMAGPART_EXPR:
5219 case COMPONENT_REF:
5220 case VIEW_CONVERT_EXPR:
5221 ret = gimplify_compound_lval (expr_p, pre_p, post_p,
5222 fallback ? fallback : fb_rvalue);
5223 break;
5224
5225 case COND_EXPR:
5226 ret = gimplify_cond_expr (expr_p, pre_p, post_p, NULL_TREE,
5227 fallback);
5228 /* C99 code may assign to an array in a structure value of a
5229 conditional expression, and this has undefined behavior
5230 only on execution, so create a temporary if an lvalue is
5231 required. */
5232 if (fallback == fb_lvalue)
5233 {
5234 *expr_p = get_initialized_tmp_var (*expr_p, pre_p, post_p);
5235 lang_hooks.mark_addressable (*expr_p);
5236 }
5237 break;
5238
5239 case CALL_EXPR:
5240 ret = gimplify_call_expr (expr_p, pre_p, fallback != fb_none);
5241 /* C99 code may assign to an array in a structure returned
5242 from a function, and this has undefined behavior only on
5243 execution, so create a temporary if an lvalue is
5244 required. */
5245 if (fallback == fb_lvalue)
5246 {
5247 *expr_p = get_initialized_tmp_var (*expr_p, pre_p, post_p);
5248 lang_hooks.mark_addressable (*expr_p);
5249 }
5250 break;
5251
5252 case TREE_LIST:
5253 gcc_unreachable ();
5254
5255 case COMPOUND_EXPR:
5256 ret = gimplify_compound_expr (expr_p, pre_p, fallback != fb_none);
5257 break;
5258
5259 case MODIFY_EXPR:
5260 case INIT_EXPR:
5261 ret = gimplify_modify_expr (expr_p, pre_p, post_p,
5262 fallback != fb_none);
5263 break;
5264
5265 case TRUTH_ANDIF_EXPR:
5266 case TRUTH_ORIF_EXPR:
5267 ret = gimplify_boolean_expr (expr_p);
5268 break;
5269
5270 case TRUTH_NOT_EXPR:
5271 TREE_OPERAND (*expr_p, 0)
5272 = gimple_boolify (TREE_OPERAND (*expr_p, 0));
5273 ret = gimplify_expr (&TREE_OPERAND (*expr_p, 0), pre_p, post_p,
5274 is_gimple_val, fb_rvalue);
5275 recalculate_side_effects (*expr_p);
5276 break;
5277
5278 case ADDR_EXPR:
5279 ret = gimplify_addr_expr (expr_p, pre_p, post_p);
5280 break;
5281
5282 case VA_ARG_EXPR:
5283 ret = gimplify_va_arg_expr (expr_p, pre_p, post_p);
5284 break;
5285
5286 case CONVERT_EXPR:
5287 case NOP_EXPR:
5288 if (IS_EMPTY_STMT (*expr_p))
5289 {
5290 ret = GS_ALL_DONE;
5291 break;
5292 }
5293
5294 if (VOID_TYPE_P (TREE_TYPE (*expr_p))
5295 || fallback == fb_none)
5296 {
5297 /* Just strip a conversion to void (or in void context) and
5298 try again. */
5299 *expr_p = TREE_OPERAND (*expr_p, 0);
5300 break;
5301 }
5302
5303 ret = gimplify_conversion (expr_p);
5304 if (ret == GS_ERROR)
5305 break;
5306 if (*expr_p != save_expr)
5307 break;
5308 /* FALLTHRU */
5309
5310 case FIX_TRUNC_EXPR:
5311 case FIX_CEIL_EXPR:
5312 case FIX_FLOOR_EXPR:
5313 case FIX_ROUND_EXPR:
5314 /* unary_expr: ... | '(' cast ')' val | ... */
5315 ret = gimplify_expr (&TREE_OPERAND (*expr_p, 0), pre_p, post_p,
5316 is_gimple_val, fb_rvalue);
5317 recalculate_side_effects (*expr_p);
5318 break;
5319
5320 case INDIRECT_REF:
5321 *expr_p = fold_indirect_ref (*expr_p);
5322 if (*expr_p != save_expr)
5323 break;
5324 /* else fall through. */
5325 case ALIGN_INDIRECT_REF:
5326 case MISALIGNED_INDIRECT_REF:
5327 ret = gimplify_expr (&TREE_OPERAND (*expr_p, 0), pre_p, post_p,
5328 is_gimple_reg, fb_rvalue);
5329 recalculate_side_effects (*expr_p);
5330 break;
5331
5332 /* Constants need not be gimplified. */
5333 case INTEGER_CST:
5334 case REAL_CST:
5335 case STRING_CST:
5336 case COMPLEX_CST:
5337 case VECTOR_CST:
5338 ret = GS_ALL_DONE;
5339 break;
5340
5341 case CONST_DECL:
5342 /* If we require an lvalue, such as for ADDR_EXPR, retain the
5343 CONST_DECL node. Otherwise the decl is replaceable by its
5344 value. */
5345 /* ??? Should be == fb_lvalue, but ADDR_EXPR passes fb_either. */
5346 if (fallback & fb_lvalue)
5347 ret = GS_ALL_DONE;
5348 else
5349 *expr_p = DECL_INITIAL (*expr_p);
5350 break;
5351
5352 case DECL_EXPR:
5353 ret = gimplify_decl_expr (expr_p);
5354 break;
5355
5356 case EXC_PTR_EXPR:
5357 /* FIXME make this a decl. */
5358 ret = GS_ALL_DONE;
5359 break;
5360
5361 case BIND_EXPR:
5362 ret = gimplify_bind_expr (expr_p, NULL, pre_p);
5363 break;
5364
5365 case LOOP_EXPR:
5366 ret = gimplify_loop_expr (expr_p, pre_p);
5367 break;
5368
5369 case SWITCH_EXPR:
5370 ret = gimplify_switch_expr (expr_p, pre_p);
5371 break;
5372
5373 case EXIT_EXPR:
5374 ret = gimplify_exit_expr (expr_p);
5375 break;
5376
5377 case GOTO_EXPR:
5378 /* If the target is not LABEL, then it is a computed jump
5379 and the target needs to be gimplified. */
5380 if (TREE_CODE (GOTO_DESTINATION (*expr_p)) != LABEL_DECL)
5381 ret = gimplify_expr (&GOTO_DESTINATION (*expr_p), pre_p,
5382 NULL, is_gimple_val, fb_rvalue);
5383 break;
5384
5385 case LABEL_EXPR:
5386 ret = GS_ALL_DONE;
5387 gcc_assert (decl_function_context (LABEL_EXPR_LABEL (*expr_p))
5388 == current_function_decl);
5389 break;
5390
5391 case CASE_LABEL_EXPR:
5392 ret = gimplify_case_label_expr (expr_p);
5393 break;
5394
5395 case RETURN_EXPR:
5396 ret = gimplify_return_expr (*expr_p, pre_p);
5397 break;
5398
5399 case CONSTRUCTOR:
5400 /* Don't reduce this in place; let gimplify_init_constructor work its
5401 magic. Buf if we're just elaborating this for side effects, just
5402 gimplify any element that has side-effects. */
5403 if (fallback == fb_none)
5404 {
5405 unsigned HOST_WIDE_INT ix;
5406 constructor_elt *ce;
5407 tree temp = NULL_TREE;
5408 for (ix = 0;
5409 VEC_iterate (constructor_elt, CONSTRUCTOR_ELTS (*expr_p),
5410 ix, ce);
5411 ix++)
5412 if (TREE_SIDE_EFFECTS (ce->value))
5413 append_to_statement_list (ce->value, &temp);
5414
5415 *expr_p = temp;
5416 ret = GS_OK;
5417 }
5418 /* C99 code may assign to an array in a constructed
5419 structure or union, and this has undefined behavior only
5420 on execution, so create a temporary if an lvalue is
5421 required. */
5422 else if (fallback == fb_lvalue)
5423 {
5424 *expr_p = get_initialized_tmp_var (*expr_p, pre_p, post_p);
5425 lang_hooks.mark_addressable (*expr_p);
5426 }
5427 else
5428 ret = GS_ALL_DONE;
5429 break;
5430
5431 /* The following are special cases that are not handled by the
5432 original GIMPLE grammar. */
5433
5434 /* SAVE_EXPR nodes are converted into a GIMPLE identifier and
5435 eliminated. */
5436 case SAVE_EXPR:
5437 ret = gimplify_save_expr (expr_p, pre_p, post_p);
5438 break;
5439
5440 case BIT_FIELD_REF:
5441 {
5442 enum gimplify_status r0, r1, r2;
5443
5444 r0 = gimplify_expr (&TREE_OPERAND (*expr_p, 0), pre_p, post_p,
5445 is_gimple_lvalue, fb_either);
5446 r1 = gimplify_expr (&TREE_OPERAND (*expr_p, 1), pre_p, post_p,
5447 is_gimple_val, fb_rvalue);
5448 r2 = gimplify_expr (&TREE_OPERAND (*expr_p, 2), pre_p, post_p,
5449 is_gimple_val, fb_rvalue);
5450 recalculate_side_effects (*expr_p);
5451
5452 ret = MIN (r0, MIN (r1, r2));
5453 }
5454 break;
5455
5456 case NON_LVALUE_EXPR:
5457 /* This should have been stripped above. */
5458 gcc_unreachable ();
5459
5460 case ASM_EXPR:
5461 ret = gimplify_asm_expr (expr_p, pre_p, post_p);
5462 break;
5463
5464 case TRY_FINALLY_EXPR:
5465 case TRY_CATCH_EXPR:
5466 gimplify_to_stmt_list (&TREE_OPERAND (*expr_p, 0));
5467 gimplify_to_stmt_list (&TREE_OPERAND (*expr_p, 1));
5468 ret = GS_ALL_DONE;
5469 break;
5470
5471 case CLEANUP_POINT_EXPR:
5472 ret = gimplify_cleanup_point_expr (expr_p, pre_p);
5473 break;
5474
5475 case TARGET_EXPR:
5476 ret = gimplify_target_expr (expr_p, pre_p, post_p);
5477 break;
5478
5479 case CATCH_EXPR:
5480 gimplify_to_stmt_list (&CATCH_BODY (*expr_p));
5481 ret = GS_ALL_DONE;
5482 break;
5483
5484 case EH_FILTER_EXPR:
5485 gimplify_to_stmt_list (&EH_FILTER_FAILURE (*expr_p));
5486 ret = GS_ALL_DONE;
5487 break;
5488
5489 case OBJ_TYPE_REF:
5490 {
5491 enum gimplify_status r0, r1;
5492 r0 = gimplify_expr (&OBJ_TYPE_REF_OBJECT (*expr_p), pre_p, post_p,
5493 is_gimple_val, fb_rvalue);
5494 r1 = gimplify_expr (&OBJ_TYPE_REF_EXPR (*expr_p), pre_p, post_p,
5495 is_gimple_val, fb_rvalue);
5496 ret = MIN (r0, r1);
5497 }
5498 break;
5499
5500 case LABEL_DECL:
5501 /* We get here when taking the address of a label. We mark
5502 the label as "forced"; meaning it can never be removed and
5503 it is a potential target for any computed goto. */
5504 FORCED_LABEL (*expr_p) = 1;
5505 ret = GS_ALL_DONE;
5506 break;
5507
5508 case STATEMENT_LIST:
5509 ret = gimplify_statement_list (expr_p);
5510 break;
5511
5512 case WITH_SIZE_EXPR:
5513 {
5514 gimplify_expr (&TREE_OPERAND (*expr_p, 0), pre_p,
5515 post_p == &internal_post ? NULL : post_p,
5516 gimple_test_f, fallback);
5517 gimplify_expr (&TREE_OPERAND (*expr_p, 1), pre_p, post_p,
5518 is_gimple_val, fb_rvalue);
5519 }
5520 break;
5521
5522 case VAR_DECL:
5523 case PARM_DECL:
5524 ret = gimplify_var_or_parm_decl (expr_p);
5525 break;
5526
5527 case SSA_NAME:
5528 /* Allow callbacks into the gimplifier during optimization. */
5529 ret = GS_ALL_DONE;
5530 break;
5531
5532 case OMP_PARALLEL:
5533 ret = gimplify_omp_parallel (expr_p, pre_p);
5534 break;
5535
5536 case OMP_FOR:
5537 ret = gimplify_omp_for (expr_p, pre_p);
5538 break;
5539
5540 case OMP_SECTIONS:
5541 case OMP_SINGLE:
5542 ret = gimplify_omp_workshare (expr_p, pre_p);
5543 break;
5544
5545 case OMP_SECTION:
5546 case OMP_MASTER:
5547 case OMP_ORDERED:
5548 case OMP_CRITICAL:
5549 gimplify_to_stmt_list (&OMP_BODY (*expr_p));
5550 break;
5551
5552 case OMP_ATOMIC:
5553 ret = gimplify_omp_atomic (expr_p, pre_p);
5554 break;
5555
5556 case OMP_RETURN_EXPR:
5557 ret = GS_ALL_DONE;
5558 break;
5559
5560 default:
5561 switch (TREE_CODE_CLASS (TREE_CODE (*expr_p)))
5562 {
5563 case tcc_comparison:
5564 /* If this is a comparison of objects of aggregate type,
5565 handle it specially (by converting to a call to
5566 memcmp). It would be nice to only have to do this
5567 for variable-sized objects, but then we'd have to
5568 allow the same nest of reference nodes we allow for
5569 MODIFY_EXPR and that's too complex. */
5570 if (!AGGREGATE_TYPE_P (TREE_TYPE (TREE_OPERAND (*expr_p, 1))))
5571 goto expr_2;
5572 ret = gimplify_variable_sized_compare (expr_p);
5573 break;
5574
5575 /* If *EXPR_P does not need to be special-cased, handle it
5576 according to its class. */
5577 case tcc_unary:
5578 ret = gimplify_expr (&TREE_OPERAND (*expr_p, 0), pre_p,
5579 post_p, is_gimple_val, fb_rvalue);
5580 break;
5581
5582 case tcc_binary:
5583 expr_2:
5584 {
5585 enum gimplify_status r0, r1;
5586
5587 r0 = gimplify_expr (&TREE_OPERAND (*expr_p, 0), pre_p,
5588 post_p, is_gimple_val, fb_rvalue);
5589 r1 = gimplify_expr (&TREE_OPERAND (*expr_p, 1), pre_p,
5590 post_p, is_gimple_val, fb_rvalue);
5591
5592 ret = MIN (r0, r1);
5593 break;
5594 }
5595
5596 case tcc_declaration:
5597 case tcc_constant:
5598 ret = GS_ALL_DONE;
5599 goto dont_recalculate;
5600
5601 default:
5602 gcc_assert (TREE_CODE (*expr_p) == TRUTH_AND_EXPR
5603 || TREE_CODE (*expr_p) == TRUTH_OR_EXPR
5604 || TREE_CODE (*expr_p) == TRUTH_XOR_EXPR);
5605 goto expr_2;
5606 }
5607
5608 recalculate_side_effects (*expr_p);
5609 dont_recalculate:
5610 break;
5611 }
5612
5613 /* If we replaced *expr_p, gimplify again. */
5614 if (ret == GS_OK && (*expr_p == NULL || *expr_p == save_expr))
5615 ret = GS_ALL_DONE;
5616 }
5617 while (ret == GS_OK);
5618
5619 /* If we encountered an error_mark somewhere nested inside, either
5620 stub out the statement or propagate the error back out. */
5621 if (ret == GS_ERROR)
5622 {
5623 if (is_statement)
5624 *expr_p = NULL;
5625 goto out;
5626 }
5627
5628 /* This was only valid as a return value from the langhook, which
5629 we handled. Make sure it doesn't escape from any other context. */
5630 gcc_assert (ret != GS_UNHANDLED);
5631
5632 if (fallback == fb_none && *expr_p && !is_gimple_stmt (*expr_p))
5633 {
5634 /* We aren't looking for a value, and we don't have a valid
5635 statement. If it doesn't have side-effects, throw it away. */
5636 if (!TREE_SIDE_EFFECTS (*expr_p))
5637 *expr_p = NULL;
5638 else if (!TREE_THIS_VOLATILE (*expr_p))
5639 {
5640 /* This is probably a _REF that contains something nested that
5641 has side effects. Recurse through the operands to find it. */
5642 enum tree_code code = TREE_CODE (*expr_p);
5643
5644 switch (code)
5645 {
5646 case COMPONENT_REF:
5647 case REALPART_EXPR: case IMAGPART_EXPR:
5648 gimplify_expr (&TREE_OPERAND (*expr_p, 0), pre_p, post_p,
5649 gimple_test_f, fallback);
5650 break;
5651
5652 case ARRAY_REF: case ARRAY_RANGE_REF:
5653 gimplify_expr (&TREE_OPERAND (*expr_p, 0), pre_p, post_p,
5654 gimple_test_f, fallback);
5655 gimplify_expr (&TREE_OPERAND (*expr_p, 1), pre_p, post_p,
5656 gimple_test_f, fallback);
5657 break;
5658
5659 default:
5660 /* Anything else with side-effects must be converted to
5661 a valid statement before we get here. */
5662 gcc_unreachable ();
5663 }
5664
5665 *expr_p = NULL;
5666 }
5667 else if (COMPLETE_TYPE_P (TREE_TYPE (*expr_p)))
5668 {
5669 /* Historically, the compiler has treated a bare
5670 reference to a volatile lvalue as forcing a load. */
5671 tree type = TYPE_MAIN_VARIANT (TREE_TYPE (*expr_p));
5672 /* Normally, we do want to create a temporary for a
5673 TREE_ADDRESSABLE type because such a type should not be
5674 copied by bitwise-assignment. However, we make an
5675 exception here, as all we are doing here is ensuring that
5676 we read the bytes that make up the type. We use
5677 create_tmp_var_raw because create_tmp_var will abort when
5678 given a TREE_ADDRESSABLE type. */
5679 tree tmp = create_tmp_var_raw (type, "vol");
5680 gimple_add_tmp_var (tmp);
5681 *expr_p = build2 (MODIFY_EXPR, type, tmp, *expr_p);
5682 }
5683 else
5684 /* We can't do anything useful with a volatile reference to
5685 incomplete type, so just throw it away. */
5686 *expr_p = NULL;
5687 }
5688
5689 /* If we are gimplifying at the statement level, we're done. Tack
5690 everything together and replace the original statement with the
5691 gimplified form. */
5692 if (fallback == fb_none || is_statement)
5693 {
5694 if (internal_pre || internal_post)
5695 {
5696 append_to_statement_list (*expr_p, &internal_pre);
5697 append_to_statement_list (internal_post, &internal_pre);
5698 annotate_all_with_locus (&internal_pre, input_location);
5699 *expr_p = internal_pre;
5700 }
5701 else if (!*expr_p)
5702 ;
5703 else if (TREE_CODE (*expr_p) == STATEMENT_LIST)
5704 annotate_all_with_locus (expr_p, input_location);
5705 else
5706 annotate_one_with_locus (*expr_p, input_location);
5707 goto out;
5708 }
5709
5710 /* Otherwise we're gimplifying a subexpression, so the resulting value is
5711 interesting. */
5712
5713 /* If it's sufficiently simple already, we're done. Unless we are
5714 handling some post-effects internally; if that's the case, we need to
5715 copy into a temp before adding the post-effects to the tree. */
5716 if (!internal_post && (*gimple_test_f) (*expr_p))
5717 goto out;
5718
5719 /* Otherwise, we need to create a new temporary for the gimplified
5720 expression. */
5721
5722 /* We can't return an lvalue if we have an internal postqueue. The
5723 object the lvalue refers to would (probably) be modified by the
5724 postqueue; we need to copy the value out first, which means an
5725 rvalue. */
5726 if ((fallback & fb_lvalue) && !internal_post
5727 && is_gimple_addressable (*expr_p))
5728 {
5729 /* An lvalue will do. Take the address of the expression, store it
5730 in a temporary, and replace the expression with an INDIRECT_REF of
5731 that temporary. */
5732 tmp = build_fold_addr_expr (*expr_p);
5733 gimplify_expr (&tmp, pre_p, post_p, is_gimple_reg, fb_rvalue);
5734 *expr_p = build1 (INDIRECT_REF, TREE_TYPE (TREE_TYPE (tmp)), tmp);
5735 }
5736 else if ((fallback & fb_rvalue) && is_gimple_formal_tmp_rhs (*expr_p))
5737 {
5738 gcc_assert (!VOID_TYPE_P (TREE_TYPE (*expr_p)));
5739
5740 /* An rvalue will do. Assign the gimplified expression into a new
5741 temporary TMP and replace the original expression with TMP. */
5742
5743 if (internal_post || (fallback & fb_lvalue))
5744 /* The postqueue might change the value of the expression between
5745 the initialization and use of the temporary, so we can't use a
5746 formal temp. FIXME do we care? */
5747 *expr_p = get_initialized_tmp_var (*expr_p, pre_p, post_p);
5748 else
5749 *expr_p = get_formal_tmp_var (*expr_p, pre_p);
5750
5751 if (TREE_CODE (*expr_p) != SSA_NAME)
5752 DECL_GIMPLE_FORMAL_TEMP_P (*expr_p) = 1;
5753 }
5754 else
5755 {
5756 #ifdef ENABLE_CHECKING
5757 if (!(fallback & fb_mayfail))
5758 {
5759 fprintf (stderr, "gimplification failed:\n");
5760 print_generic_expr (stderr, *expr_p, 0);
5761 debug_tree (*expr_p);
5762 internal_error ("gimplification failed");
5763 }
5764 #endif
5765 gcc_assert (fallback & fb_mayfail);
5766 /* If this is an asm statement, and the user asked for the
5767 impossible, don't die. Fail and let gimplify_asm_expr
5768 issue an error. */
5769 ret = GS_ERROR;
5770 goto out;
5771 }
5772
5773 /* Make sure the temporary matches our predicate. */
5774 gcc_assert ((*gimple_test_f) (*expr_p));
5775
5776 if (internal_post)
5777 {
5778 annotate_all_with_locus (&internal_post, input_location);
5779 append_to_statement_list (internal_post, pre_p);
5780 }
5781
5782 out:
5783 input_location = saved_location;
5784 return ret;
5785 }
5786
5787 /* Look through TYPE for variable-sized objects and gimplify each such
5788 size that we find. Add to LIST_P any statements generated. */
5789
5790 void
5791 gimplify_type_sizes (tree type, tree *list_p)
5792 {
5793 tree field, t;
5794
5795 if (type == NULL || type == error_mark_node)
5796 return;
5797
5798 /* We first do the main variant, then copy into any other variants. */
5799 type = TYPE_MAIN_VARIANT (type);
5800
5801 /* Avoid infinite recursion. */
5802 if (TYPE_SIZES_GIMPLIFIED (type))
5803 return;
5804
5805 TYPE_SIZES_GIMPLIFIED (type) = 1;
5806
5807 switch (TREE_CODE (type))
5808 {
5809 case INTEGER_TYPE:
5810 case ENUMERAL_TYPE:
5811 case BOOLEAN_TYPE:
5812 case CHAR_TYPE:
5813 case REAL_TYPE:
5814 gimplify_one_sizepos (&TYPE_MIN_VALUE (type), list_p);
5815 gimplify_one_sizepos (&TYPE_MAX_VALUE (type), list_p);
5816
5817 for (t = TYPE_NEXT_VARIANT (type); t; t = TYPE_NEXT_VARIANT (t))
5818 {
5819 TYPE_MIN_VALUE (t) = TYPE_MIN_VALUE (type);
5820 TYPE_MAX_VALUE (t) = TYPE_MAX_VALUE (type);
5821 }
5822 break;
5823
5824 case ARRAY_TYPE:
5825 /* These types may not have declarations, so handle them here. */
5826 gimplify_type_sizes (TREE_TYPE (type), list_p);
5827 gimplify_type_sizes (TYPE_DOMAIN (type), list_p);
5828 break;
5829
5830 case RECORD_TYPE:
5831 case UNION_TYPE:
5832 case QUAL_UNION_TYPE:
5833 for (field = TYPE_FIELDS (type); field; field = TREE_CHAIN (field))
5834 if (TREE_CODE (field) == FIELD_DECL)
5835 {
5836 gimplify_one_sizepos (&DECL_FIELD_OFFSET (field), list_p);
5837 gimplify_type_sizes (TREE_TYPE (field), list_p);
5838 }
5839 break;
5840
5841 case POINTER_TYPE:
5842 case REFERENCE_TYPE:
5843 gimplify_type_sizes (TREE_TYPE (type), list_p);
5844 break;
5845
5846 default:
5847 break;
5848 }
5849
5850 gimplify_one_sizepos (&TYPE_SIZE (type), list_p);
5851 gimplify_one_sizepos (&TYPE_SIZE_UNIT (type), list_p);
5852
5853 for (t = TYPE_NEXT_VARIANT (type); t; t = TYPE_NEXT_VARIANT (t))
5854 {
5855 TYPE_SIZE (t) = TYPE_SIZE (type);
5856 TYPE_SIZE_UNIT (t) = TYPE_SIZE_UNIT (type);
5857 TYPE_SIZES_GIMPLIFIED (t) = 1;
5858 }
5859 }
5860
5861 /* A subroutine of gimplify_type_sizes to make sure that *EXPR_P,
5862 a size or position, has had all of its SAVE_EXPRs evaluated.
5863 We add any required statements to STMT_P. */
5864
5865 void
5866 gimplify_one_sizepos (tree *expr_p, tree *stmt_p)
5867 {
5868 tree type, expr = *expr_p;
5869
5870 /* We don't do anything if the value isn't there, is constant, or contains
5871 A PLACEHOLDER_EXPR. We also don't want to do anything if it's already
5872 a VAR_DECL. If it's a VAR_DECL from another function, the gimplifier
5873 will want to replace it with a new variable, but that will cause problems
5874 if this type is from outside the function. It's OK to have that here. */
5875 if (expr == NULL_TREE || TREE_CONSTANT (expr)
5876 || TREE_CODE (expr) == VAR_DECL
5877 || CONTAINS_PLACEHOLDER_P (expr))
5878 return;
5879
5880 type = TREE_TYPE (expr);
5881 *expr_p = unshare_expr (expr);
5882
5883 gimplify_expr (expr_p, stmt_p, NULL, is_gimple_val, fb_rvalue);
5884 expr = *expr_p;
5885
5886 /* Verify that we've an exact type match with the original expression.
5887 In particular, we do not wish to drop a "sizetype" in favour of a
5888 type of similar dimensions. We don't want to pollute the generic
5889 type-stripping code with this knowledge because it doesn't matter
5890 for the bulk of GENERIC/GIMPLE. It only matters that TYPE_SIZE_UNIT
5891 and friends retain their "sizetype-ness". */
5892 if (TREE_TYPE (expr) != type
5893 && TREE_CODE (type) == INTEGER_TYPE
5894 && TYPE_IS_SIZETYPE (type))
5895 {
5896 tree tmp;
5897
5898 *expr_p = create_tmp_var (type, NULL);
5899 tmp = build1 (NOP_EXPR, type, expr);
5900 tmp = build2 (MODIFY_EXPR, type, *expr_p, expr);
5901 if (EXPR_HAS_LOCATION (expr))
5902 SET_EXPR_LOCUS (tmp, EXPR_LOCUS (expr));
5903 else
5904 SET_EXPR_LOCATION (tmp, input_location);
5905
5906 gimplify_and_add (tmp, stmt_p);
5907 }
5908 }
5909 \f
5910 #ifdef ENABLE_CHECKING
5911 /* Compare types A and B for a "close enough" match. */
5912
5913 static bool
5914 cpt_same_type (tree a, tree b)
5915 {
5916 if (lang_hooks.types_compatible_p (a, b))
5917 return true;
5918
5919 /* ??? The C++ FE decomposes METHOD_TYPES to FUNCTION_TYPES and doesn't
5920 link them together. This routine is intended to catch type errors
5921 that will affect the optimizers, and the optimizers don't add new
5922 dereferences of function pointers, so ignore it. */
5923 if ((TREE_CODE (a) == FUNCTION_TYPE || TREE_CODE (a) == METHOD_TYPE)
5924 && (TREE_CODE (b) == FUNCTION_TYPE || TREE_CODE (b) == METHOD_TYPE))
5925 return true;
5926
5927 /* ??? The C FE pushes type qualifiers after the fact into the type of
5928 the element from the type of the array. See build_unary_op's handling
5929 of ADDR_EXPR. This seems wrong -- if we were going to do this, we
5930 should have done it when creating the variable in the first place.
5931 Alternately, why aren't the two array types made variants? */
5932 if (TREE_CODE (a) == ARRAY_TYPE && TREE_CODE (b) == ARRAY_TYPE)
5933 return cpt_same_type (TREE_TYPE (a), TREE_TYPE (b));
5934
5935 /* And because of those, we have to recurse down through pointers. */
5936 if (POINTER_TYPE_P (a) && POINTER_TYPE_P (b))
5937 return cpt_same_type (TREE_TYPE (a), TREE_TYPE (b));
5938
5939 return false;
5940 }
5941
5942 /* Check for some cases of the front end missing cast expressions.
5943 The type of a dereference should correspond to the pointer type;
5944 similarly the type of an address should match its object. */
5945
5946 static tree
5947 check_pointer_types_r (tree *tp, int *walk_subtrees ATTRIBUTE_UNUSED,
5948 void *data ATTRIBUTE_UNUSED)
5949 {
5950 tree t = *tp;
5951 tree ptype, otype, dtype;
5952
5953 switch (TREE_CODE (t))
5954 {
5955 case INDIRECT_REF:
5956 case ARRAY_REF:
5957 otype = TREE_TYPE (t);
5958 ptype = TREE_TYPE (TREE_OPERAND (t, 0));
5959 dtype = TREE_TYPE (ptype);
5960 gcc_assert (cpt_same_type (otype, dtype));
5961 break;
5962
5963 case ADDR_EXPR:
5964 ptype = TREE_TYPE (t);
5965 otype = TREE_TYPE (TREE_OPERAND (t, 0));
5966 dtype = TREE_TYPE (ptype);
5967 if (!cpt_same_type (otype, dtype))
5968 {
5969 /* &array is allowed to produce a pointer to the element, rather than
5970 a pointer to the array type. We must allow this in order to
5971 properly represent assigning the address of an array in C into
5972 pointer to the element type. */
5973 gcc_assert (TREE_CODE (otype) == ARRAY_TYPE
5974 && POINTER_TYPE_P (ptype)
5975 && cpt_same_type (TREE_TYPE (otype), dtype));
5976 break;
5977 }
5978 break;
5979
5980 default:
5981 return NULL_TREE;
5982 }
5983
5984
5985 return NULL_TREE;
5986 }
5987 #endif
5988
5989 /* Gimplify the body of statements pointed to by BODY_P. FNDECL is the
5990 function decl containing BODY. */
5991
5992 void
5993 gimplify_body (tree *body_p, tree fndecl, bool do_parms)
5994 {
5995 location_t saved_location = input_location;
5996 tree body, parm_stmts;
5997
5998 timevar_push (TV_TREE_GIMPLIFY);
5999
6000 gcc_assert (gimplify_ctxp == NULL);
6001 push_gimplify_context ();
6002
6003 /* Unshare most shared trees in the body and in that of any nested functions.
6004 It would seem we don't have to do this for nested functions because
6005 they are supposed to be output and then the outer function gimplified
6006 first, but the g++ front end doesn't always do it that way. */
6007 unshare_body (body_p, fndecl);
6008 unvisit_body (body_p, fndecl);
6009
6010 /* Make sure input_location isn't set to something wierd. */
6011 input_location = DECL_SOURCE_LOCATION (fndecl);
6012
6013 /* Resolve callee-copies. This has to be done before processing
6014 the body so that DECL_VALUE_EXPR gets processed correctly. */
6015 parm_stmts = do_parms ? gimplify_parameters () : NULL;
6016
6017 /* Gimplify the function's body. */
6018 gimplify_stmt (body_p);
6019 body = *body_p;
6020
6021 if (!body)
6022 body = alloc_stmt_list ();
6023 else if (TREE_CODE (body) == STATEMENT_LIST)
6024 {
6025 tree t = expr_only (*body_p);
6026 if (t)
6027 body = t;
6028 }
6029
6030 /* If there isn't an outer BIND_EXPR, add one. */
6031 if (TREE_CODE (body) != BIND_EXPR)
6032 {
6033 tree b = build3 (BIND_EXPR, void_type_node, NULL_TREE,
6034 NULL_TREE, NULL_TREE);
6035 TREE_SIDE_EFFECTS (b) = 1;
6036 append_to_statement_list_force (body, &BIND_EXPR_BODY (b));
6037 body = b;
6038 }
6039
6040 /* If we had callee-copies statements, insert them at the beginning
6041 of the function. */
6042 if (parm_stmts)
6043 {
6044 append_to_statement_list_force (BIND_EXPR_BODY (body), &parm_stmts);
6045 BIND_EXPR_BODY (body) = parm_stmts;
6046 }
6047
6048 /* Unshare again, in case gimplification was sloppy. */
6049 unshare_all_trees (body);
6050
6051 *body_p = body;
6052
6053 pop_gimplify_context (body);
6054 gcc_assert (gimplify_ctxp == NULL);
6055
6056 #ifdef ENABLE_CHECKING
6057 walk_tree (body_p, check_pointer_types_r, NULL, NULL);
6058 #endif
6059
6060 timevar_pop (TV_TREE_GIMPLIFY);
6061 input_location = saved_location;
6062 }
6063
6064 /* Entry point to the gimplification pass. FNDECL is the FUNCTION_DECL
6065 node for the function we want to gimplify. */
6066
6067 void
6068 gimplify_function_tree (tree fndecl)
6069 {
6070 tree oldfn, parm, ret;
6071
6072 oldfn = current_function_decl;
6073 current_function_decl = fndecl;
6074 cfun = DECL_STRUCT_FUNCTION (fndecl);
6075 if (cfun == NULL)
6076 allocate_struct_function (fndecl);
6077
6078 for (parm = DECL_ARGUMENTS (fndecl); parm ; parm = TREE_CHAIN (parm))
6079 {
6080 /* Preliminarily mark non-addressed complex variables as eligible
6081 for promotion to gimple registers. We'll transform their uses
6082 as we find them. */
6083 if (TREE_CODE (TREE_TYPE (parm)) == COMPLEX_TYPE
6084 && !TREE_THIS_VOLATILE (parm)
6085 && !needs_to_live_in_memory (parm))
6086 DECL_COMPLEX_GIMPLE_REG_P (parm) = 1;
6087 }
6088
6089 ret = DECL_RESULT (fndecl);
6090 if (TREE_CODE (TREE_TYPE (ret)) == COMPLEX_TYPE
6091 && !needs_to_live_in_memory (ret))
6092 DECL_COMPLEX_GIMPLE_REG_P (ret) = 1;
6093
6094 gimplify_body (&DECL_SAVED_TREE (fndecl), fndecl, true);
6095
6096 /* If we're instrumenting function entry/exit, then prepend the call to
6097 the entry hook and wrap the whole function in a TRY_FINALLY_EXPR to
6098 catch the exit hook. */
6099 /* ??? Add some way to ignore exceptions for this TFE. */
6100 if (flag_instrument_function_entry_exit
6101 && ! DECL_NO_INSTRUMENT_FUNCTION_ENTRY_EXIT (fndecl))
6102 {
6103 tree tf, x, bind;
6104
6105 tf = build2 (TRY_FINALLY_EXPR, void_type_node, NULL, NULL);
6106 TREE_SIDE_EFFECTS (tf) = 1;
6107 x = DECL_SAVED_TREE (fndecl);
6108 append_to_statement_list (x, &TREE_OPERAND (tf, 0));
6109 x = implicit_built_in_decls[BUILT_IN_PROFILE_FUNC_EXIT];
6110 x = build_function_call_expr (x, NULL);
6111 append_to_statement_list (x, &TREE_OPERAND (tf, 1));
6112
6113 bind = build3 (BIND_EXPR, void_type_node, NULL, NULL, NULL);
6114 TREE_SIDE_EFFECTS (bind) = 1;
6115 x = implicit_built_in_decls[BUILT_IN_PROFILE_FUNC_ENTER];
6116 x = build_function_call_expr (x, NULL);
6117 append_to_statement_list (x, &BIND_EXPR_BODY (bind));
6118 append_to_statement_list (tf, &BIND_EXPR_BODY (bind));
6119
6120 DECL_SAVED_TREE (fndecl) = bind;
6121 }
6122
6123 current_function_decl = oldfn;
6124 cfun = oldfn ? DECL_STRUCT_FUNCTION (oldfn) : NULL;
6125 }
6126
6127 \f
6128 /* Expands EXPR to list of gimple statements STMTS. If SIMPLE is true,
6129 force the result to be either ssa_name or an invariant, otherwise
6130 just force it to be a rhs expression. If VAR is not NULL, make the
6131 base variable of the final destination be VAR if suitable. */
6132
6133 tree
6134 force_gimple_operand (tree expr, tree *stmts, bool simple, tree var)
6135 {
6136 tree t;
6137 enum gimplify_status ret;
6138 gimple_predicate gimple_test_f;
6139
6140 *stmts = NULL_TREE;
6141
6142 if (is_gimple_val (expr))
6143 return expr;
6144
6145 gimple_test_f = simple ? is_gimple_val : is_gimple_reg_rhs;
6146
6147 push_gimplify_context ();
6148 gimplify_ctxp->into_ssa = in_ssa_p;
6149
6150 if (var)
6151 expr = build2 (MODIFY_EXPR, TREE_TYPE (var), var, expr);
6152
6153 ret = gimplify_expr (&expr, stmts, NULL,
6154 gimple_test_f, fb_rvalue);
6155 gcc_assert (ret != GS_ERROR);
6156
6157 if (referenced_vars)
6158 {
6159 for (t = gimplify_ctxp->temps; t ; t = TREE_CHAIN (t))
6160 add_referenced_tmp_var (t);
6161 }
6162
6163 pop_gimplify_context (NULL);
6164
6165 return expr;
6166 }
6167
6168 /* Invokes force_gimple_operand for EXPR with parameters SIMPLE_P and VAR. If
6169 some statements are produced, emits them before BSI. */
6170
6171 tree
6172 force_gimple_operand_bsi (block_stmt_iterator *bsi, tree expr,
6173 bool simple_p, tree var)
6174 {
6175 tree stmts;
6176
6177 expr = force_gimple_operand (expr, &stmts, simple_p, var);
6178 if (stmts)
6179 bsi_insert_before (bsi, stmts, BSI_SAME_STMT);
6180
6181 return expr;
6182 }
6183
6184 #include "gt-gimplify.h"