1 /* Tree lowering pass. This pass converts the GENERIC functions-as-trees
2 tree representation into the GIMPLE form.
3 Copyright (C) 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2010
4 Free Software Foundation, Inc.
5 Major work done by Sebastian Pop <s.pop@laposte.net>,
6 Diego Novillo <dnovillo@redhat.com> and Jason Merrill <jason@redhat.com>.
8 This file is part of GCC.
10 GCC is free software; you can redistribute it and/or modify it under
11 the terms of the GNU General Public License as published by the Free
12 Software Foundation; either version 3, or (at your option) any later
15 GCC is distributed in the hope that it will be useful, but WITHOUT ANY
16 WARRANTY; without even the implied warranty of MERCHANTABILITY or
17 FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
20 You should have received a copy of the GNU General Public License
21 along with GCC; see the file COPYING3. If not see
22 <http://www.gnu.org/licenses/>. */
26 #include "coretypes.h"
31 #include "tree-iterator.h"
32 #include "tree-inline.h"
33 #include "diagnostic.h"
34 #include "langhooks.h"
35 #include "langhooks-def.h"
36 #include "tree-flow.h"
50 #include "pointer-set.h"
51 #include "splay-tree.h"
54 #include "tree-pass.h"
57 enum gimplify_omp_var_data
63 GOVD_FIRSTPRIVATE = 16,
64 GOVD_LASTPRIVATE = 32,
67 GOVD_DEBUG_PRIVATE = 256,
68 GOVD_PRIVATE_OUTER_REF = 512,
69 GOVD_DATA_SHARE_CLASS = (GOVD_SHARED | GOVD_PRIVATE | GOVD_FIRSTPRIVATE
70 | GOVD_LASTPRIVATE | GOVD_REDUCTION | GOVD_LOCAL)
79 ORT_COMBINED_PARALLEL = 3
82 struct gimplify_omp_ctx
84 struct gimplify_omp_ctx *outer_context;
86 struct pointer_set_t *privatized_types;
88 enum omp_clause_default_kind default_kind;
89 enum omp_region_type region_type;
92 static struct gimplify_ctx *gimplify_ctxp;
93 static struct gimplify_omp_ctx *gimplify_omp_ctxp;
96 /* Formal (expression) temporary table handling: Multiple occurrences of
97 the same scalar expression are evaluated into the same temporary. */
99 typedef struct gimple_temp_hash_elt
102 tree temp; /* Value */
105 /* Forward declarations. */
106 static enum gimplify_status gimplify_compound_expr (tree *, gimple_seq *, bool);
108 /* Mark X addressable. Unlike the langhook we expect X to be in gimple
109 form and we don't do any syntax checking. */
111 mark_addressable (tree x)
113 while (handled_component_p (x))
114 x = TREE_OPERAND (x, 0);
115 if (TREE_CODE (x) != VAR_DECL
116 && TREE_CODE (x) != PARM_DECL
117 && TREE_CODE (x) != RESULT_DECL)
119 TREE_ADDRESSABLE (x) = 1;
122 /* Return a hash value for a formal temporary table entry. */
125 gimple_tree_hash (const void *p)
127 tree t = ((const elt_t *) p)->val;
128 return iterative_hash_expr (t, 0);
131 /* Compare two formal temporary table entries. */
134 gimple_tree_eq (const void *p1, const void *p2)
136 tree t1 = ((const elt_t *) p1)->val;
137 tree t2 = ((const elt_t *) p2)->val;
138 enum tree_code code = TREE_CODE (t1);
140 if (TREE_CODE (t2) != code
141 || TREE_TYPE (t1) != TREE_TYPE (t2))
144 if (!operand_equal_p (t1, t2, 0))
147 /* Only allow them to compare equal if they also hash equal; otherwise
148 results are nondeterminate, and we fail bootstrap comparison. */
149 gcc_assert (gimple_tree_hash (p1) == gimple_tree_hash (p2));
154 /* Link gimple statement GS to the end of the sequence *SEQ_P. If
155 *SEQ_P is NULL, a new sequence is allocated. This function is
156 similar to gimple_seq_add_stmt, but does not scan the operands.
157 During gimplification, we need to manipulate statement sequences
158 before the def/use vectors have been constructed. */
161 gimplify_seq_add_stmt (gimple_seq *seq_p, gimple gs)
163 gimple_stmt_iterator si;
169 *seq_p = gimple_seq_alloc ();
171 si = gsi_last (*seq_p);
173 gsi_insert_after_without_update (&si, gs, GSI_NEW_STMT);
176 /* Append sequence SRC to the end of sequence *DST_P. If *DST_P is
177 NULL, a new sequence is allocated. This function is
178 similar to gimple_seq_add_seq, but does not scan the operands.
179 During gimplification, we need to manipulate statement sequences
180 before the def/use vectors have been constructed. */
183 gimplify_seq_add_seq (gimple_seq *dst_p, gimple_seq src)
185 gimple_stmt_iterator si;
191 *dst_p = gimple_seq_alloc ();
193 si = gsi_last (*dst_p);
194 gsi_insert_seq_after_without_update (&si, src, GSI_NEW_STMT);
197 /* Set up a context for the gimplifier. */
200 push_gimplify_context (struct gimplify_ctx *c)
202 memset (c, '\0', sizeof (*c));
203 c->prev_context = gimplify_ctxp;
207 /* Tear down a context for the gimplifier. If BODY is non-null, then
208 put the temporaries into the outer BIND_EXPR. Otherwise, put them
211 BODY is not a sequence, but the first tuple in a sequence. */
214 pop_gimplify_context (gimple body)
216 struct gimplify_ctx *c = gimplify_ctxp;
218 gcc_assert (c && (c->bind_expr_stack == NULL
219 || VEC_empty (gimple, c->bind_expr_stack)));
220 VEC_free (gimple, heap, c->bind_expr_stack);
221 gimplify_ctxp = c->prev_context;
224 declare_vars (c->temps, body, false);
226 record_vars (c->temps);
229 htab_delete (c->temp_htab);
233 gimple_push_bind_expr (gimple gimple_bind)
235 if (gimplify_ctxp->bind_expr_stack == NULL)
236 gimplify_ctxp->bind_expr_stack = VEC_alloc (gimple, heap, 8);
237 VEC_safe_push (gimple, heap, gimplify_ctxp->bind_expr_stack, gimple_bind);
241 gimple_pop_bind_expr (void)
243 VEC_pop (gimple, gimplify_ctxp->bind_expr_stack);
247 gimple_current_bind_expr (void)
249 return VEC_last (gimple, gimplify_ctxp->bind_expr_stack);
252 /* Return the stack GIMPLE_BINDs created during gimplification. */
255 gimple_bind_expr_stack (void)
257 return gimplify_ctxp->bind_expr_stack;
260 /* Returns true iff there is a COND_EXPR between us and the innermost
261 CLEANUP_POINT_EXPR. This info is used by gimple_push_cleanup. */
264 gimple_conditional_context (void)
266 return gimplify_ctxp->conditions > 0;
269 /* Note that we've entered a COND_EXPR. */
272 gimple_push_condition (void)
274 #ifdef ENABLE_GIMPLE_CHECKING
275 if (gimplify_ctxp->conditions == 0)
276 gcc_assert (gimple_seq_empty_p (gimplify_ctxp->conditional_cleanups));
278 ++(gimplify_ctxp->conditions);
281 /* Note that we've left a COND_EXPR. If we're back at unconditional scope
282 now, add any conditional cleanups we've seen to the prequeue. */
285 gimple_pop_condition (gimple_seq *pre_p)
287 int conds = --(gimplify_ctxp->conditions);
289 gcc_assert (conds >= 0);
292 gimplify_seq_add_seq (pre_p, gimplify_ctxp->conditional_cleanups);
293 gimplify_ctxp->conditional_cleanups = NULL;
297 /* A stable comparison routine for use with splay trees and DECLs. */
300 splay_tree_compare_decl_uid (splay_tree_key xa, splay_tree_key xb)
305 return DECL_UID (a) - DECL_UID (b);
308 /* Create a new omp construct that deals with variable remapping. */
310 static struct gimplify_omp_ctx *
311 new_omp_context (enum omp_region_type region_type)
313 struct gimplify_omp_ctx *c;
315 c = XCNEW (struct gimplify_omp_ctx);
316 c->outer_context = gimplify_omp_ctxp;
317 c->variables = splay_tree_new (splay_tree_compare_decl_uid, 0, 0);
318 c->privatized_types = pointer_set_create ();
319 c->location = input_location;
320 c->region_type = region_type;
321 if (region_type != ORT_TASK)
322 c->default_kind = OMP_CLAUSE_DEFAULT_SHARED;
324 c->default_kind = OMP_CLAUSE_DEFAULT_UNSPECIFIED;
329 /* Destroy an omp construct that deals with variable remapping. */
332 delete_omp_context (struct gimplify_omp_ctx *c)
334 splay_tree_delete (c->variables);
335 pointer_set_destroy (c->privatized_types);
339 static void omp_add_variable (struct gimplify_omp_ctx *, tree, unsigned int);
340 static bool omp_notice_variable (struct gimplify_omp_ctx *, tree, bool);
342 /* A subroutine of append_to_statement_list{,_force}. T is not NULL. */
345 append_to_statement_list_1 (tree t, tree *list_p)
348 tree_stmt_iterator i;
352 if (t && TREE_CODE (t) == STATEMENT_LIST)
357 *list_p = list = alloc_stmt_list ();
361 tsi_link_after (&i, t, TSI_CONTINUE_LINKING);
364 /* Add T to the end of the list container pointed to by LIST_P.
365 If T is an expression with no effects, it is ignored. */
368 append_to_statement_list (tree t, tree *list_p)
370 if (t && TREE_SIDE_EFFECTS (t))
371 append_to_statement_list_1 (t, list_p);
374 /* Similar, but the statement is always added, regardless of side effects. */
377 append_to_statement_list_force (tree t, tree *list_p)
380 append_to_statement_list_1 (t, list_p);
383 /* Both gimplify the statement T and append it to *SEQ_P. This function
384 behaves exactly as gimplify_stmt, but you don't have to pass T as a
388 gimplify_and_add (tree t, gimple_seq *seq_p)
390 gimplify_stmt (&t, seq_p);
393 /* Gimplify statement T into sequence *SEQ_P, and return the first
394 tuple in the sequence of generated tuples for this statement.
395 Return NULL if gimplifying T produced no tuples. */
398 gimplify_and_return_first (tree t, gimple_seq *seq_p)
400 gimple_stmt_iterator last = gsi_last (*seq_p);
402 gimplify_and_add (t, seq_p);
404 if (!gsi_end_p (last))
407 return gsi_stmt (last);
410 return gimple_seq_first_stmt (*seq_p);
413 /* Strip off a legitimate source ending from the input string NAME of
414 length LEN. Rather than having to know the names used by all of
415 our front ends, we strip off an ending of a period followed by
416 up to five characters. (Java uses ".class".) */
419 remove_suffix (char *name, int len)
423 for (i = 2; i < 8 && len > i; i++)
425 if (name[len - i] == '.')
427 name[len - i] = '\0';
433 /* Create a new temporary name with PREFIX. Returns an identifier. */
435 static GTY(()) unsigned int tmp_var_id_num;
438 create_tmp_var_name (const char *prefix)
444 char *preftmp = ASTRDUP (prefix);
446 remove_suffix (preftmp, strlen (preftmp));
450 ASM_FORMAT_PRIVATE_NAME (tmp_name, prefix ? prefix : "T", tmp_var_id_num++);
451 return get_identifier (tmp_name);
455 /* Create a new temporary variable declaration of type TYPE.
456 Does NOT push it into the current binding. */
459 create_tmp_var_raw (tree type, const char *prefix)
464 /* Make the type of the variable writable. */
465 new_type = build_type_variant (type, 0, 0);
466 TYPE_ATTRIBUTES (new_type) = TYPE_ATTRIBUTES (type);
468 tmp_var = build_decl (input_location,
469 VAR_DECL, prefix ? create_tmp_var_name (prefix) : NULL,
472 /* The variable was declared by the compiler. */
473 DECL_ARTIFICIAL (tmp_var) = 1;
474 /* And we don't want debug info for it. */
475 DECL_IGNORED_P (tmp_var) = 1;
477 /* Make the variable writable. */
478 TREE_READONLY (tmp_var) = 0;
480 DECL_EXTERNAL (tmp_var) = 0;
481 TREE_STATIC (tmp_var) = 0;
482 TREE_USED (tmp_var) = 1;
487 /* Create a new temporary variable declaration of type TYPE. DOES push the
488 variable into the current binding. Further, assume that this is called
489 only from gimplification or optimization, at which point the creation of
490 certain types are bugs. */
493 create_tmp_var (tree type, const char *prefix)
497 /* We don't allow types that are addressable (meaning we can't make copies),
498 or incomplete. We also used to reject every variable size objects here,
499 but now support those for which a constant upper bound can be obtained.
500 The processing for variable sizes is performed in gimple_add_tmp_var,
501 point at which it really matters and possibly reached via paths not going
502 through this function, e.g. after direct calls to create_tmp_var_raw. */
503 gcc_assert (!TREE_ADDRESSABLE (type) && COMPLETE_TYPE_P (type));
505 tmp_var = create_tmp_var_raw (type, prefix);
506 gimple_add_tmp_var (tmp_var);
510 /* Create a new temporary variable declaration of type TYPE by calling
511 create_tmp_var and if TYPE is a vector or a complex number, mark the new
512 temporary as gimple register. */
515 create_tmp_reg (tree type, const char *prefix)
519 tmp = create_tmp_var (type, prefix);
520 if (TREE_CODE (type) == COMPLEX_TYPE
521 || TREE_CODE (type) == VECTOR_TYPE)
522 DECL_GIMPLE_REG_P (tmp) = 1;
527 /* Create a temporary with a name derived from VAL. Subroutine of
528 lookup_tmp_var; nobody else should call this function. */
531 create_tmp_from_val (tree val)
533 return create_tmp_var (TREE_TYPE (val), get_name (val));
536 /* Create a temporary to hold the value of VAL. If IS_FORMAL, try to reuse
537 an existing expression temporary. */
540 lookup_tmp_var (tree val, bool is_formal)
544 /* If not optimizing, never really reuse a temporary. local-alloc
545 won't allocate any variable that is used in more than one basic
546 block, which means it will go into memory, causing much extra
547 work in reload and final and poorer code generation, outweighing
548 the extra memory allocation here. */
549 if (!optimize || !is_formal || TREE_SIDE_EFFECTS (val))
550 ret = create_tmp_from_val (val);
557 if (gimplify_ctxp->temp_htab == NULL)
558 gimplify_ctxp->temp_htab
559 = htab_create (1000, gimple_tree_hash, gimple_tree_eq, free);
560 slot = htab_find_slot (gimplify_ctxp->temp_htab, (void *)&elt, INSERT);
563 elt_p = XNEW (elt_t);
565 elt_p->temp = ret = create_tmp_from_val (val);
566 *slot = (void *) elt_p;
570 elt_p = (elt_t *) *slot;
579 /* Return true if T is a CALL_EXPR or an expression that can be
580 assignmed to a temporary. Note that this predicate should only be
581 used during gimplification. See the rationale for this in
582 gimplify_modify_expr. */
585 is_gimple_reg_rhs_or_call (tree t)
587 return (get_gimple_rhs_class (TREE_CODE (t)) != GIMPLE_INVALID_RHS
588 || TREE_CODE (t) == CALL_EXPR);
591 /* Return true if T is a valid memory RHS or a CALL_EXPR. Note that
592 this predicate should only be used during gimplification. See the
593 rationale for this in gimplify_modify_expr. */
596 is_gimple_mem_rhs_or_call (tree t)
598 /* If we're dealing with a renamable type, either source or dest must be
599 a renamed variable. */
600 if (is_gimple_reg_type (TREE_TYPE (t)))
601 return is_gimple_val (t);
603 return (is_gimple_val (t) || is_gimple_lvalue (t)
604 || TREE_CODE (t) == CALL_EXPR);
607 /* Helper for get_formal_tmp_var and get_initialized_tmp_var. */
610 internal_get_tmp_var (tree val, gimple_seq *pre_p, gimple_seq *post_p,
615 /* Notice that we explicitly allow VAL to be a CALL_EXPR so that we
616 can create an INIT_EXPR and convert it into a GIMPLE_CALL below. */
617 gimplify_expr (&val, pre_p, post_p, is_gimple_reg_rhs_or_call,
620 t = lookup_tmp_var (val, is_formal);
623 && (TREE_CODE (TREE_TYPE (t)) == COMPLEX_TYPE
624 || TREE_CODE (TREE_TYPE (t)) == VECTOR_TYPE))
625 DECL_GIMPLE_REG_P (t) = 1;
627 mod = build2 (INIT_EXPR, TREE_TYPE (t), t, unshare_expr (val));
629 if (EXPR_HAS_LOCATION (val))
630 SET_EXPR_LOCATION (mod, EXPR_LOCATION (val));
632 SET_EXPR_LOCATION (mod, input_location);
634 /* gimplify_modify_expr might want to reduce this further. */
635 gimplify_and_add (mod, pre_p);
638 /* If we're gimplifying into ssa, gimplify_modify_expr will have
639 given our temporary an SSA name. Find and return it. */
640 if (gimplify_ctxp->into_ssa)
642 gimple last = gimple_seq_last_stmt (*pre_p);
643 t = gimple_get_lhs (last);
649 /* Returns a formal temporary variable initialized with VAL. PRE_P is as
650 in gimplify_expr. Only use this function if:
652 1) The value of the unfactored expression represented by VAL will not
653 change between the initialization and use of the temporary, and
654 2) The temporary will not be otherwise modified.
656 For instance, #1 means that this is inappropriate for SAVE_EXPR temps,
657 and #2 means it is inappropriate for && temps.
659 For other cases, use get_initialized_tmp_var instead. */
662 get_formal_tmp_var (tree val, gimple_seq *pre_p)
664 return internal_get_tmp_var (val, pre_p, NULL, true);
667 /* Returns a temporary variable initialized with VAL. PRE_P and POST_P
668 are as in gimplify_expr. */
671 get_initialized_tmp_var (tree val, gimple_seq *pre_p, gimple_seq *post_p)
673 return internal_get_tmp_var (val, pre_p, post_p, false);
676 /* Declares all the variables in VARS in SCOPE. If DEBUG_INFO is
677 true, generate debug info for them; otherwise don't. */
680 declare_vars (tree vars, gimple scope, bool debug_info)
687 gcc_assert (gimple_code (scope) == GIMPLE_BIND);
689 temps = nreverse (last);
691 block = gimple_bind_block (scope);
692 gcc_assert (!block || TREE_CODE (block) == BLOCK);
693 if (!block || !debug_info)
695 TREE_CHAIN (last) = gimple_bind_vars (scope);
696 gimple_bind_set_vars (scope, temps);
700 /* We need to attach the nodes both to the BIND_EXPR and to its
701 associated BLOCK for debugging purposes. The key point here
702 is that the BLOCK_VARS of the BIND_EXPR_BLOCK of a BIND_EXPR
703 is a subchain of the BIND_EXPR_VARS of the BIND_EXPR. */
704 if (BLOCK_VARS (block))
705 BLOCK_VARS (block) = chainon (BLOCK_VARS (block), temps);
708 gimple_bind_set_vars (scope,
709 chainon (gimple_bind_vars (scope), temps));
710 BLOCK_VARS (block) = temps;
716 /* For VAR a VAR_DECL of variable size, try to find a constant upper bound
717 for the size and adjust DECL_SIZE/DECL_SIZE_UNIT accordingly. Abort if
718 no such upper bound can be obtained. */
721 force_constant_size (tree var)
723 /* The only attempt we make is by querying the maximum size of objects
724 of the variable's type. */
726 HOST_WIDE_INT max_size;
728 gcc_assert (TREE_CODE (var) == VAR_DECL);
730 max_size = max_int_size_in_bytes (TREE_TYPE (var));
732 gcc_assert (max_size >= 0);
735 = build_int_cst (TREE_TYPE (DECL_SIZE_UNIT (var)), max_size);
737 = build_int_cst (TREE_TYPE (DECL_SIZE (var)), max_size * BITS_PER_UNIT);
741 gimple_add_tmp_var (tree tmp)
743 gcc_assert (!TREE_CHAIN (tmp) && !DECL_SEEN_IN_BIND_EXPR_P (tmp));
745 /* Later processing assumes that the object size is constant, which might
746 not be true at this point. Force the use of a constant upper bound in
748 if (!host_integerp (DECL_SIZE_UNIT (tmp), 1))
749 force_constant_size (tmp);
751 DECL_CONTEXT (tmp) = current_function_decl;
752 DECL_SEEN_IN_BIND_EXPR_P (tmp) = 1;
756 TREE_CHAIN (tmp) = gimplify_ctxp->temps;
757 gimplify_ctxp->temps = tmp;
759 /* Mark temporaries local within the nearest enclosing parallel. */
760 if (gimplify_omp_ctxp)
762 struct gimplify_omp_ctx *ctx = gimplify_omp_ctxp;
763 while (ctx && ctx->region_type == ORT_WORKSHARE)
764 ctx = ctx->outer_context;
766 omp_add_variable (ctx, tmp, GOVD_LOCAL | GOVD_SEEN);
775 /* This case is for nested functions. We need to expose the locals
777 body_seq = gimple_body (current_function_decl);
778 declare_vars (tmp, gimple_seq_first_stmt (body_seq), false);
782 /* Determines whether to assign a location to the statement GS. */
785 should_carry_location_p (gimple gs)
787 /* Don't emit a line note for a label. We particularly don't want to
788 emit one for the break label, since it doesn't actually correspond
789 to the beginning of the loop/switch. */
790 if (gimple_code (gs) == GIMPLE_LABEL)
797 /* Return true if a location should not be emitted for this statement
798 by annotate_one_with_location. */
801 gimple_do_not_emit_location_p (gimple g)
803 return gimple_plf (g, GF_PLF_1);
806 /* Mark statement G so a location will not be emitted by
807 annotate_one_with_location. */
810 gimple_set_do_not_emit_location (gimple g)
812 /* The PLF flags are initialized to 0 when a new tuple is created,
813 so no need to initialize it anywhere. */
814 gimple_set_plf (g, GF_PLF_1, true);
817 /* Set the location for gimple statement GS to LOCATION. */
820 annotate_one_with_location (gimple gs, location_t location)
822 if (!gimple_has_location (gs)
823 && !gimple_do_not_emit_location_p (gs)
824 && should_carry_location_p (gs))
825 gimple_set_location (gs, location);
829 /* Set LOCATION for all the statements after iterator GSI in sequence
830 SEQ. If GSI is pointing to the end of the sequence, start with the
831 first statement in SEQ. */
834 annotate_all_with_location_after (gimple_seq seq, gimple_stmt_iterator gsi,
838 gsi = gsi_start (seq);
842 for (; !gsi_end_p (gsi); gsi_next (&gsi))
843 annotate_one_with_location (gsi_stmt (gsi), location);
847 /* Set the location for all the statements in a sequence STMT_P to LOCATION. */
850 annotate_all_with_location (gimple_seq stmt_p, location_t location)
852 gimple_stmt_iterator i;
854 if (gimple_seq_empty_p (stmt_p))
857 for (i = gsi_start (stmt_p); !gsi_end_p (i); gsi_next (&i))
859 gimple gs = gsi_stmt (i);
860 annotate_one_with_location (gs, location);
865 /* Similar to copy_tree_r() but do not copy SAVE_EXPR or TARGET_EXPR nodes.
866 These nodes model computations that should only be done once. If we
867 were to unshare something like SAVE_EXPR(i++), the gimplification
868 process would create wrong code. */
871 mostly_copy_tree_r (tree *tp, int *walk_subtrees, void *data)
873 enum tree_code code = TREE_CODE (*tp);
874 /* Don't unshare types, decls, constants and SAVE_EXPR nodes. */
875 if (TREE_CODE_CLASS (code) == tcc_type
876 || TREE_CODE_CLASS (code) == tcc_declaration
877 || TREE_CODE_CLASS (code) == tcc_constant
878 || code == SAVE_EXPR || code == TARGET_EXPR
879 /* We can't do anything sensible with a BLOCK used as an expression,
880 but we also can't just die when we see it because of non-expression
881 uses. So just avert our eyes and cross our fingers. Silly Java. */
886 gcc_assert (code != BIND_EXPR);
887 copy_tree_r (tp, walk_subtrees, data);
893 /* Callback for walk_tree to unshare most of the shared trees rooted at
894 *TP. If *TP has been visited already (i.e., TREE_VISITED (*TP) == 1),
895 then *TP is deep copied by calling copy_tree_r.
897 This unshares the same trees as copy_tree_r with the exception of
898 SAVE_EXPR nodes. These nodes model computations that should only be
899 done once. If we were to unshare something like SAVE_EXPR(i++), the
900 gimplification process would create wrong code. */
903 copy_if_shared_r (tree *tp, int *walk_subtrees ATTRIBUTE_UNUSED,
904 void *data ATTRIBUTE_UNUSED)
907 enum tree_code code = TREE_CODE (t);
909 /* Skip types, decls, and constants. But we do want to look at their
910 types and the bounds of types. Mark them as visited so we properly
911 unmark their subtrees on the unmark pass. If we've already seen them,
912 don't look down further. */
913 if (TREE_CODE_CLASS (code) == tcc_type
914 || TREE_CODE_CLASS (code) == tcc_declaration
915 || TREE_CODE_CLASS (code) == tcc_constant)
917 if (TREE_VISITED (t))
920 TREE_VISITED (t) = 1;
923 /* If this node has been visited already, unshare it and don't look
925 else if (TREE_VISITED (t))
927 walk_tree (tp, mostly_copy_tree_r, NULL, NULL);
931 /* Otherwise, mark the tree as visited and keep looking. */
933 TREE_VISITED (t) = 1;
939 unmark_visited_r (tree *tp, int *walk_subtrees ATTRIBUTE_UNUSED,
940 void *data ATTRIBUTE_UNUSED)
942 if (TREE_VISITED (*tp))
943 TREE_VISITED (*tp) = 0;
950 /* Unshare all the trees in BODY_P, a pointer into the body of FNDECL, and the
951 bodies of any nested functions if we are unsharing the entire body of
955 unshare_body (tree *body_p, tree fndecl)
957 struct cgraph_node *cgn = cgraph_node (fndecl);
959 walk_tree (body_p, copy_if_shared_r, NULL, NULL);
960 if (body_p == &DECL_SAVED_TREE (fndecl))
961 for (cgn = cgn->nested; cgn; cgn = cgn->next_nested)
962 unshare_body (&DECL_SAVED_TREE (cgn->decl), cgn->decl);
965 /* Likewise, but mark all trees as not visited. */
968 unvisit_body (tree *body_p, tree fndecl)
970 struct cgraph_node *cgn = cgraph_node (fndecl);
972 walk_tree (body_p, unmark_visited_r, NULL, NULL);
973 if (body_p == &DECL_SAVED_TREE (fndecl))
974 for (cgn = cgn->nested; cgn; cgn = cgn->next_nested)
975 unvisit_body (&DECL_SAVED_TREE (cgn->decl), cgn->decl);
978 /* Unconditionally make an unshared copy of EXPR. This is used when using
979 stored expressions which span multiple functions, such as BINFO_VTABLE,
980 as the normal unsharing process can't tell that they're shared. */
983 unshare_expr (tree expr)
985 walk_tree (&expr, mostly_copy_tree_r, NULL, NULL);
989 /* WRAPPER is a code such as BIND_EXPR or CLEANUP_POINT_EXPR which can both
990 contain statements and have a value. Assign its value to a temporary
991 and give it void_type_node. Returns the temporary, or NULL_TREE if
992 WRAPPER was already void. */
995 voidify_wrapper_expr (tree wrapper, tree temp)
997 tree type = TREE_TYPE (wrapper);
998 if (type && !VOID_TYPE_P (type))
1002 /* Set p to point to the body of the wrapper. Loop until we find
1003 something that isn't a wrapper. */
1004 for (p = &wrapper; p && *p; )
1006 switch (TREE_CODE (*p))
1009 TREE_SIDE_EFFECTS (*p) = 1;
1010 TREE_TYPE (*p) = void_type_node;
1011 /* For a BIND_EXPR, the body is operand 1. */
1012 p = &BIND_EXPR_BODY (*p);
1015 case CLEANUP_POINT_EXPR:
1016 case TRY_FINALLY_EXPR:
1017 case TRY_CATCH_EXPR:
1018 TREE_SIDE_EFFECTS (*p) = 1;
1019 TREE_TYPE (*p) = void_type_node;
1020 p = &TREE_OPERAND (*p, 0);
1023 case STATEMENT_LIST:
1025 tree_stmt_iterator i = tsi_last (*p);
1026 TREE_SIDE_EFFECTS (*p) = 1;
1027 TREE_TYPE (*p) = void_type_node;
1028 p = tsi_end_p (i) ? NULL : tsi_stmt_ptr (i);
1033 /* Advance to the last statement. Set all container types to void. */
1034 for (; TREE_CODE (*p) == COMPOUND_EXPR; p = &TREE_OPERAND (*p, 1))
1036 TREE_SIDE_EFFECTS (*p) = 1;
1037 TREE_TYPE (*p) = void_type_node;
1047 if (p == NULL || IS_EMPTY_STMT (*p))
1051 /* The wrapper is on the RHS of an assignment that we're pushing
1053 gcc_assert (TREE_CODE (temp) == INIT_EXPR
1054 || TREE_CODE (temp) == MODIFY_EXPR);
1055 TREE_OPERAND (temp, 1) = *p;
1060 temp = create_tmp_var (type, "retval");
1061 *p = build2 (INIT_EXPR, type, temp, *p);
1070 /* Prepare calls to builtins to SAVE and RESTORE the stack as well as
1071 a temporary through which they communicate. */
1074 build_stack_save_restore (gimple *save, gimple *restore)
1078 *save = gimple_build_call (implicit_built_in_decls[BUILT_IN_STACK_SAVE], 0);
1079 tmp_var = create_tmp_var (ptr_type_node, "saved_stack");
1080 gimple_call_set_lhs (*save, tmp_var);
1082 *restore = gimple_build_call (implicit_built_in_decls[BUILT_IN_STACK_RESTORE],
1086 /* Gimplify a BIND_EXPR. Just voidify and recurse. */
1088 static enum gimplify_status
1089 gimplify_bind_expr (tree *expr_p, gimple_seq *pre_p)
1091 tree bind_expr = *expr_p;
1092 bool old_save_stack = gimplify_ctxp->save_stack;
1097 tree temp = voidify_wrapper_expr (bind_expr, NULL);
1099 /* Mark variables seen in this bind expr. */
1100 for (t = BIND_EXPR_VARS (bind_expr); t ; t = TREE_CHAIN (t))
1102 if (TREE_CODE (t) == VAR_DECL)
1104 struct gimplify_omp_ctx *ctx = gimplify_omp_ctxp;
1106 /* Mark variable as local. */
1107 if (ctx && !is_global_var (t)
1108 && (! DECL_SEEN_IN_BIND_EXPR_P (t)
1109 || splay_tree_lookup (ctx->variables,
1110 (splay_tree_key) t) == NULL))
1111 omp_add_variable (gimplify_omp_ctxp, t, GOVD_LOCAL | GOVD_SEEN);
1113 DECL_SEEN_IN_BIND_EXPR_P (t) = 1;
1115 if (DECL_HARD_REGISTER (t) && !is_global_var (t) && cfun)
1116 cfun->has_local_explicit_reg_vars = true;
1119 /* Preliminarily mark non-addressed complex variables as eligible
1120 for promotion to gimple registers. We'll transform their uses
1122 We exclude complex types if not optimizing because they can be
1123 subject to partial stores in GNU C by means of the __real__ and
1124 __imag__ operators and we cannot promote them to total stores
1125 (see gimplify_modify_expr_complex_part). */
1127 && (TREE_CODE (TREE_TYPE (t)) == COMPLEX_TYPE
1128 || TREE_CODE (TREE_TYPE (t)) == VECTOR_TYPE)
1129 && !TREE_THIS_VOLATILE (t)
1130 && (TREE_CODE (t) == VAR_DECL && !DECL_HARD_REGISTER (t))
1131 && !needs_to_live_in_memory (t))
1132 DECL_GIMPLE_REG_P (t) = 1;
1135 gimple_bind = gimple_build_bind (BIND_EXPR_VARS (bind_expr), NULL,
1136 BIND_EXPR_BLOCK (bind_expr));
1137 gimple_push_bind_expr (gimple_bind);
1139 gimplify_ctxp->save_stack = false;
1141 /* Gimplify the body into the GIMPLE_BIND tuple's body. */
1143 gimplify_stmt (&BIND_EXPR_BODY (bind_expr), &body);
1144 gimple_bind_set_body (gimple_bind, body);
1146 if (gimplify_ctxp->save_stack)
1148 gimple stack_save, stack_restore, gs;
1149 gimple_seq cleanup, new_body;
1151 /* Save stack on entry and restore it on exit. Add a try_finally
1152 block to achieve this. Note that mudflap depends on the
1153 format of the emitted code: see mx_register_decls(). */
1154 build_stack_save_restore (&stack_save, &stack_restore);
1156 cleanup = new_body = NULL;
1157 gimplify_seq_add_stmt (&cleanup, stack_restore);
1158 gs = gimple_build_try (gimple_bind_body (gimple_bind), cleanup,
1159 GIMPLE_TRY_FINALLY);
1161 gimplify_seq_add_stmt (&new_body, stack_save);
1162 gimplify_seq_add_stmt (&new_body, gs);
1163 gimple_bind_set_body (gimple_bind, new_body);
1166 gimplify_ctxp->save_stack = old_save_stack;
1167 gimple_pop_bind_expr ();
1169 gimplify_seq_add_stmt (pre_p, gimple_bind);
1177 *expr_p = NULL_TREE;
1181 /* Gimplify a RETURN_EXPR. If the expression to be returned is not a
1182 GIMPLE value, it is assigned to a new temporary and the statement is
1183 re-written to return the temporary.
1185 PRE_P points to the sequence where side effects that must happen before
1186 STMT should be stored. */
1188 static enum gimplify_status
1189 gimplify_return_expr (tree stmt, gimple_seq *pre_p)
1192 tree ret_expr = TREE_OPERAND (stmt, 0);
1193 tree result_decl, result;
1195 if (ret_expr == error_mark_node)
1199 || TREE_CODE (ret_expr) == RESULT_DECL
1200 || ret_expr == error_mark_node)
1202 gimple ret = gimple_build_return (ret_expr);
1203 gimple_set_no_warning (ret, TREE_NO_WARNING (stmt));
1204 gimplify_seq_add_stmt (pre_p, ret);
1208 if (VOID_TYPE_P (TREE_TYPE (TREE_TYPE (current_function_decl))))
1209 result_decl = NULL_TREE;
1212 result_decl = TREE_OPERAND (ret_expr, 0);
1214 /* See through a return by reference. */
1215 if (TREE_CODE (result_decl) == INDIRECT_REF)
1216 result_decl = TREE_OPERAND (result_decl, 0);
1218 gcc_assert ((TREE_CODE (ret_expr) == MODIFY_EXPR
1219 || TREE_CODE (ret_expr) == INIT_EXPR)
1220 && TREE_CODE (result_decl) == RESULT_DECL);
1223 /* If aggregate_value_p is true, then we can return the bare RESULT_DECL.
1224 Recall that aggregate_value_p is FALSE for any aggregate type that is
1225 returned in registers. If we're returning values in registers, then
1226 we don't want to extend the lifetime of the RESULT_DECL, particularly
1227 across another call. In addition, for those aggregates for which
1228 hard_function_value generates a PARALLEL, we'll die during normal
1229 expansion of structure assignments; there's special code in expand_return
1230 to handle this case that does not exist in expand_expr. */
1233 else if (aggregate_value_p (result_decl, TREE_TYPE (current_function_decl)))
1235 if (TREE_CODE (DECL_SIZE (result_decl)) != INTEGER_CST)
1237 if (!TYPE_SIZES_GIMPLIFIED (TREE_TYPE (result_decl)))
1238 gimplify_type_sizes (TREE_TYPE (result_decl), pre_p);
1239 /* Note that we don't use gimplify_vla_decl because the RESULT_DECL
1240 should be effectively allocated by the caller, i.e. all calls to
1241 this function must be subject to the Return Slot Optimization. */
1242 gimplify_one_sizepos (&DECL_SIZE (result_decl), pre_p);
1243 gimplify_one_sizepos (&DECL_SIZE_UNIT (result_decl), pre_p);
1245 result = result_decl;
1247 else if (gimplify_ctxp->return_temp)
1248 result = gimplify_ctxp->return_temp;
1251 result = create_tmp_reg (TREE_TYPE (result_decl), NULL);
1253 /* ??? With complex control flow (usually involving abnormal edges),
1254 we can wind up warning about an uninitialized value for this. Due
1255 to how this variable is constructed and initialized, this is never
1256 true. Give up and never warn. */
1257 TREE_NO_WARNING (result) = 1;
1259 gimplify_ctxp->return_temp = result;
1262 /* Smash the lhs of the MODIFY_EXPR to the temporary we plan to use.
1263 Then gimplify the whole thing. */
1264 if (result != result_decl)
1265 TREE_OPERAND (ret_expr, 0) = result;
1267 gimplify_and_add (TREE_OPERAND (stmt, 0), pre_p);
1269 ret = gimple_build_return (result);
1270 gimple_set_no_warning (ret, TREE_NO_WARNING (stmt));
1271 gimplify_seq_add_stmt (pre_p, ret);
1277 gimplify_vla_decl (tree decl, gimple_seq *seq_p)
1279 /* This is a variable-sized decl. Simplify its size and mark it
1280 for deferred expansion. Note that mudflap depends on the format
1281 of the emitted code: see mx_register_decls(). */
1282 tree t, addr, ptr_type;
1284 gimplify_one_sizepos (&DECL_SIZE (decl), seq_p);
1285 gimplify_one_sizepos (&DECL_SIZE_UNIT (decl), seq_p);
1287 /* All occurrences of this decl in final gimplified code will be
1288 replaced by indirection. Setting DECL_VALUE_EXPR does two
1289 things: First, it lets the rest of the gimplifier know what
1290 replacement to use. Second, it lets the debug info know
1291 where to find the value. */
1292 ptr_type = build_pointer_type (TREE_TYPE (decl));
1293 addr = create_tmp_var (ptr_type, get_name (decl));
1294 DECL_IGNORED_P (addr) = 0;
1295 t = build_fold_indirect_ref (addr);
1296 SET_DECL_VALUE_EXPR (decl, t);
1297 DECL_HAS_VALUE_EXPR_P (decl) = 1;
1299 t = built_in_decls[BUILT_IN_ALLOCA];
1300 t = build_call_expr (t, 1, DECL_SIZE_UNIT (decl));
1301 t = fold_convert (ptr_type, t);
1302 t = build2 (MODIFY_EXPR, TREE_TYPE (addr), addr, t);
1304 gimplify_and_add (t, seq_p);
1306 /* Indicate that we need to restore the stack level when the
1307 enclosing BIND_EXPR is exited. */
1308 gimplify_ctxp->save_stack = true;
1312 /* Gimplifies a DECL_EXPR node *STMT_P by making any necessary allocation
1313 and initialization explicit. */
1315 static enum gimplify_status
1316 gimplify_decl_expr (tree *stmt_p, gimple_seq *seq_p)
1318 tree stmt = *stmt_p;
1319 tree decl = DECL_EXPR_DECL (stmt);
1321 *stmt_p = NULL_TREE;
1323 if (TREE_TYPE (decl) == error_mark_node)
1326 if ((TREE_CODE (decl) == TYPE_DECL
1327 || TREE_CODE (decl) == VAR_DECL)
1328 && !TYPE_SIZES_GIMPLIFIED (TREE_TYPE (decl)))
1329 gimplify_type_sizes (TREE_TYPE (decl), seq_p);
1331 if (TREE_CODE (decl) == VAR_DECL && !DECL_EXTERNAL (decl))
1333 tree init = DECL_INITIAL (decl);
1335 if (TREE_CODE (DECL_SIZE_UNIT (decl)) != INTEGER_CST
1336 || (!TREE_STATIC (decl)
1337 && flag_stack_check == GENERIC_STACK_CHECK
1338 && compare_tree_int (DECL_SIZE_UNIT (decl),
1339 STACK_CHECK_MAX_VAR_SIZE) > 0))
1340 gimplify_vla_decl (decl, seq_p);
1342 if (init && init != error_mark_node)
1344 if (!TREE_STATIC (decl))
1346 DECL_INITIAL (decl) = NULL_TREE;
1347 init = build2 (INIT_EXPR, void_type_node, decl, init);
1348 gimplify_and_add (init, seq_p);
1352 /* We must still examine initializers for static variables
1353 as they may contain a label address. */
1354 walk_tree (&init, force_labels_r, NULL, NULL);
1357 /* Some front ends do not explicitly declare all anonymous
1358 artificial variables. We compensate here by declaring the
1359 variables, though it would be better if the front ends would
1360 explicitly declare them. */
1361 if (!DECL_SEEN_IN_BIND_EXPR_P (decl)
1362 && DECL_ARTIFICIAL (decl) && DECL_NAME (decl) == NULL_TREE)
1363 gimple_add_tmp_var (decl);
1369 /* Gimplify a LOOP_EXPR. Normally this just involves gimplifying the body
1370 and replacing the LOOP_EXPR with goto, but if the loop contains an
1371 EXIT_EXPR, we need to append a label for it to jump to. */
1373 static enum gimplify_status
1374 gimplify_loop_expr (tree *expr_p, gimple_seq *pre_p)
1376 tree saved_label = gimplify_ctxp->exit_label;
1377 tree start_label = create_artificial_label (UNKNOWN_LOCATION);
1379 gimplify_seq_add_stmt (pre_p, gimple_build_label (start_label));
1381 gimplify_ctxp->exit_label = NULL_TREE;
1383 gimplify_and_add (LOOP_EXPR_BODY (*expr_p), pre_p);
1385 gimplify_seq_add_stmt (pre_p, gimple_build_goto (start_label));
1387 if (gimplify_ctxp->exit_label)
1388 gimplify_seq_add_stmt (pre_p, gimple_build_label (gimplify_ctxp->exit_label));
1390 gimplify_ctxp->exit_label = saved_label;
1396 /* Gimplifies a statement list onto a sequence. These may be created either
1397 by an enlightened front-end, or by shortcut_cond_expr. */
1399 static enum gimplify_status
1400 gimplify_statement_list (tree *expr_p, gimple_seq *pre_p)
1402 tree temp = voidify_wrapper_expr (*expr_p, NULL);
1404 tree_stmt_iterator i = tsi_start (*expr_p);
1406 while (!tsi_end_p (i))
1408 gimplify_stmt (tsi_stmt_ptr (i), pre_p);
1421 /* Compare two case labels. Because the front end should already have
1422 made sure that case ranges do not overlap, it is enough to only compare
1423 the CASE_LOW values of each case label. */
1426 compare_case_labels (const void *p1, const void *p2)
1428 const_tree const case1 = *(const_tree const*)p1;
1429 const_tree const case2 = *(const_tree const*)p2;
1431 /* The 'default' case label always goes first. */
1432 if (!CASE_LOW (case1))
1434 else if (!CASE_LOW (case2))
1437 return tree_int_cst_compare (CASE_LOW (case1), CASE_LOW (case2));
1441 /* Sort the case labels in LABEL_VEC in place in ascending order. */
1444 sort_case_labels (VEC(tree,heap)* label_vec)
1446 size_t len = VEC_length (tree, label_vec);
1447 qsort (VEC_address (tree, label_vec), len, sizeof (tree),
1448 compare_case_labels);
1452 /* Gimplify a SWITCH_EXPR, and collect a TREE_VEC of the labels it can
1455 static enum gimplify_status
1456 gimplify_switch_expr (tree *expr_p, gimple_seq *pre_p)
1458 tree switch_expr = *expr_p;
1459 gimple_seq switch_body_seq = NULL;
1460 enum gimplify_status ret;
1462 ret = gimplify_expr (&SWITCH_COND (switch_expr), pre_p, NULL, is_gimple_val,
1464 if (ret == GS_ERROR || ret == GS_UNHANDLED)
1467 if (SWITCH_BODY (switch_expr))
1469 VEC (tree,heap) *labels;
1470 VEC (tree,heap) *saved_labels;
1471 tree default_case = NULL_TREE;
1473 gimple gimple_switch;
1475 /* If someone can be bothered to fill in the labels, they can
1476 be bothered to null out the body too. */
1477 gcc_assert (!SWITCH_LABELS (switch_expr));
1479 /* save old labels, get new ones from body, then restore the old
1480 labels. Save all the things from the switch body to append after. */
1481 saved_labels = gimplify_ctxp->case_labels;
1482 gimplify_ctxp->case_labels = VEC_alloc (tree, heap, 8);
1484 gimplify_stmt (&SWITCH_BODY (switch_expr), &switch_body_seq);
1485 labels = gimplify_ctxp->case_labels;
1486 gimplify_ctxp->case_labels = saved_labels;
1489 while (i < VEC_length (tree, labels))
1491 tree elt = VEC_index (tree, labels, i);
1492 tree low = CASE_LOW (elt);
1493 bool remove_element = FALSE;
1497 /* Discard empty ranges. */
1498 tree high = CASE_HIGH (elt);
1499 if (high && tree_int_cst_lt (high, low))
1500 remove_element = TRUE;
1504 /* The default case must be the last label in the list. */
1505 gcc_assert (!default_case);
1507 remove_element = TRUE;
1511 VEC_ordered_remove (tree, labels, i);
1517 if (!VEC_empty (tree, labels))
1518 sort_case_labels (labels);
1522 tree type = TREE_TYPE (switch_expr);
1524 /* If the switch has no default label, add one, so that we jump
1525 around the switch body. If the labels already cover the whole
1526 range of type, add the default label pointing to one of the
1528 if (type == void_type_node)
1529 type = TREE_TYPE (SWITCH_COND (switch_expr));
1531 && INTEGRAL_TYPE_P (type)
1532 && TYPE_MIN_VALUE (type)
1533 && TYPE_MAX_VALUE (type)
1534 && tree_int_cst_equal (CASE_LOW (VEC_index (tree, labels, 0)),
1535 TYPE_MIN_VALUE (type)))
1537 tree low, high = CASE_HIGH (VEC_index (tree, labels, len - 1));
1539 high = CASE_LOW (VEC_index (tree, labels, len - 1));
1540 if (tree_int_cst_equal (high, TYPE_MAX_VALUE (type)))
1542 for (i = 1; i < len; i++)
1544 high = CASE_LOW (VEC_index (tree, labels, i));
1545 low = CASE_HIGH (VEC_index (tree, labels, i - 1));
1547 low = CASE_LOW (VEC_index (tree, labels, i - 1));
1548 if ((TREE_INT_CST_LOW (low) + 1
1549 != TREE_INT_CST_LOW (high))
1550 || (TREE_INT_CST_HIGH (low)
1551 + (TREE_INT_CST_LOW (high) == 0)
1552 != TREE_INT_CST_HIGH (high)))
1556 default_case = build3 (CASE_LABEL_EXPR, void_type_node,
1557 NULL_TREE, NULL_TREE,
1558 CASE_LABEL (VEC_index (tree,
1568 = build3 (CASE_LABEL_EXPR, void_type_node,
1569 NULL_TREE, NULL_TREE,
1570 create_artificial_label (UNKNOWN_LOCATION));
1571 new_default = gimple_build_label (CASE_LABEL (default_case));
1572 gimplify_seq_add_stmt (&switch_body_seq, new_default);
1576 gimple_switch = gimple_build_switch_vec (SWITCH_COND (switch_expr),
1577 default_case, labels);
1578 gimplify_seq_add_stmt (pre_p, gimple_switch);
1579 gimplify_seq_add_seq (pre_p, switch_body_seq);
1580 VEC_free(tree, heap, labels);
1583 gcc_assert (SWITCH_LABELS (switch_expr));
1589 static enum gimplify_status
1590 gimplify_case_label_expr (tree *expr_p, gimple_seq *pre_p)
1592 struct gimplify_ctx *ctxp;
1593 gimple gimple_label;
1595 /* Invalid OpenMP programs can play Duff's Device type games with
1596 #pragma omp parallel. At least in the C front end, we don't
1597 detect such invalid branches until after gimplification. */
1598 for (ctxp = gimplify_ctxp; ; ctxp = ctxp->prev_context)
1599 if (ctxp->case_labels)
1602 gimple_label = gimple_build_label (CASE_LABEL (*expr_p));
1603 VEC_safe_push (tree, heap, ctxp->case_labels, *expr_p);
1604 gimplify_seq_add_stmt (pre_p, gimple_label);
1609 /* Build a GOTO to the LABEL_DECL pointed to by LABEL_P, building it first
1613 build_and_jump (tree *label_p)
1615 if (label_p == NULL)
1616 /* If there's nowhere to jump, just fall through. */
1619 if (*label_p == NULL_TREE)
1621 tree label = create_artificial_label (UNKNOWN_LOCATION);
1625 return build1 (GOTO_EXPR, void_type_node, *label_p);
1628 /* Gimplify an EXIT_EXPR by converting to a GOTO_EXPR inside a COND_EXPR.
1629 This also involves building a label to jump to and communicating it to
1630 gimplify_loop_expr through gimplify_ctxp->exit_label. */
1632 static enum gimplify_status
1633 gimplify_exit_expr (tree *expr_p)
1635 tree cond = TREE_OPERAND (*expr_p, 0);
1638 expr = build_and_jump (&gimplify_ctxp->exit_label);
1639 expr = build3 (COND_EXPR, void_type_node, cond, expr, NULL_TREE);
1645 /* A helper function to be called via walk_tree. Mark all labels under *TP
1646 as being forced. To be called for DECL_INITIAL of static variables. */
1649 force_labels_r (tree *tp, int *walk_subtrees, void *data ATTRIBUTE_UNUSED)
1653 if (TREE_CODE (*tp) == LABEL_DECL)
1654 FORCED_LABEL (*tp) = 1;
1659 /* *EXPR_P is a COMPONENT_REF being used as an rvalue. If its type is
1660 different from its canonical type, wrap the whole thing inside a
1661 NOP_EXPR and force the type of the COMPONENT_REF to be the canonical
1664 The canonical type of a COMPONENT_REF is the type of the field being
1665 referenced--unless the field is a bit-field which can be read directly
1666 in a smaller mode, in which case the canonical type is the
1667 sign-appropriate type corresponding to that mode. */
1670 canonicalize_component_ref (tree *expr_p)
1672 tree expr = *expr_p;
1675 gcc_assert (TREE_CODE (expr) == COMPONENT_REF);
1677 if (INTEGRAL_TYPE_P (TREE_TYPE (expr)))
1678 type = TREE_TYPE (get_unwidened (expr, NULL_TREE));
1680 type = TREE_TYPE (TREE_OPERAND (expr, 1));
1682 /* One could argue that all the stuff below is not necessary for
1683 the non-bitfield case and declare it a FE error if type
1684 adjustment would be needed. */
1685 if (TREE_TYPE (expr) != type)
1687 #ifdef ENABLE_TYPES_CHECKING
1688 tree old_type = TREE_TYPE (expr);
1692 /* We need to preserve qualifiers and propagate them from
1694 type_quals = TYPE_QUALS (type)
1695 | TYPE_QUALS (TREE_TYPE (TREE_OPERAND (expr, 0)));
1696 if (TYPE_QUALS (type) != type_quals)
1697 type = build_qualified_type (TYPE_MAIN_VARIANT (type), type_quals);
1699 /* Set the type of the COMPONENT_REF to the underlying type. */
1700 TREE_TYPE (expr) = type;
1702 #ifdef ENABLE_TYPES_CHECKING
1703 /* It is now a FE error, if the conversion from the canonical
1704 type to the original expression type is not useless. */
1705 gcc_assert (useless_type_conversion_p (old_type, type));
1710 /* If a NOP conversion is changing a pointer to array of foo to a pointer
1711 to foo, embed that change in the ADDR_EXPR by converting
1716 where L is the lower bound. For simplicity, only do this for constant
1718 The constraint is that the type of &array[L] is trivially convertible
1722 canonicalize_addr_expr (tree *expr_p)
1724 tree expr = *expr_p;
1725 tree addr_expr = TREE_OPERAND (expr, 0);
1726 tree datype, ddatype, pddatype;
1728 /* We simplify only conversions from an ADDR_EXPR to a pointer type. */
1729 if (!POINTER_TYPE_P (TREE_TYPE (expr))
1730 || TREE_CODE (addr_expr) != ADDR_EXPR)
1733 /* The addr_expr type should be a pointer to an array. */
1734 datype = TREE_TYPE (TREE_TYPE (addr_expr));
1735 if (TREE_CODE (datype) != ARRAY_TYPE)
1738 /* The pointer to element type shall be trivially convertible to
1739 the expression pointer type. */
1740 ddatype = TREE_TYPE (datype);
1741 pddatype = build_pointer_type (ddatype);
1742 if (!useless_type_conversion_p (TYPE_MAIN_VARIANT (TREE_TYPE (expr)),
1746 /* The lower bound and element sizes must be constant. */
1747 if (!TYPE_SIZE_UNIT (ddatype)
1748 || TREE_CODE (TYPE_SIZE_UNIT (ddatype)) != INTEGER_CST
1749 || !TYPE_DOMAIN (datype) || !TYPE_MIN_VALUE (TYPE_DOMAIN (datype))
1750 || TREE_CODE (TYPE_MIN_VALUE (TYPE_DOMAIN (datype))) != INTEGER_CST)
1753 /* All checks succeeded. Build a new node to merge the cast. */
1754 *expr_p = build4 (ARRAY_REF, ddatype, TREE_OPERAND (addr_expr, 0),
1755 TYPE_MIN_VALUE (TYPE_DOMAIN (datype)),
1756 NULL_TREE, NULL_TREE);
1757 *expr_p = build1 (ADDR_EXPR, pddatype, *expr_p);
1759 /* We can have stripped a required restrict qualifier above. */
1760 if (!useless_type_conversion_p (TREE_TYPE (expr), TREE_TYPE (*expr_p)))
1761 *expr_p = fold_convert (TREE_TYPE (expr), *expr_p);
1764 /* *EXPR_P is a NOP_EXPR or CONVERT_EXPR. Remove it and/or other conversions
1765 underneath as appropriate. */
1767 static enum gimplify_status
1768 gimplify_conversion (tree *expr_p)
1771 location_t loc = EXPR_LOCATION (*expr_p);
1772 gcc_assert (CONVERT_EXPR_P (*expr_p));
1774 /* Then strip away all but the outermost conversion. */
1775 STRIP_SIGN_NOPS (TREE_OPERAND (*expr_p, 0));
1777 /* And remove the outermost conversion if it's useless. */
1778 if (tree_ssa_useless_type_conversion (*expr_p))
1779 *expr_p = TREE_OPERAND (*expr_p, 0);
1781 /* Attempt to avoid NOP_EXPR by producing reference to a subtype.
1782 For example this fold (subclass *)&A into &A->subclass avoiding
1783 a need for statement. */
1784 if (CONVERT_EXPR_P (*expr_p)
1785 && POINTER_TYPE_P (TREE_TYPE (*expr_p))
1786 && POINTER_TYPE_P (TREE_TYPE (TREE_OPERAND (*expr_p, 0)))
1787 && (tem = maybe_fold_offset_to_address
1788 (EXPR_LOCATION (*expr_p), TREE_OPERAND (*expr_p, 0),
1789 integer_zero_node, TREE_TYPE (*expr_p))) != NULL_TREE)
1792 /* If we still have a conversion at the toplevel,
1793 then canonicalize some constructs. */
1794 if (CONVERT_EXPR_P (*expr_p))
1796 tree sub = TREE_OPERAND (*expr_p, 0);
1798 /* If a NOP conversion is changing the type of a COMPONENT_REF
1799 expression, then canonicalize its type now in order to expose more
1800 redundant conversions. */
1801 if (TREE_CODE (sub) == COMPONENT_REF)
1802 canonicalize_component_ref (&TREE_OPERAND (*expr_p, 0));
1804 /* If a NOP conversion is changing a pointer to array of foo
1805 to a pointer to foo, embed that change in the ADDR_EXPR. */
1806 else if (TREE_CODE (sub) == ADDR_EXPR)
1807 canonicalize_addr_expr (expr_p);
1810 /* If we have a conversion to a non-register type force the
1811 use of a VIEW_CONVERT_EXPR instead. */
1812 if (CONVERT_EXPR_P (*expr_p) && !is_gimple_reg_type (TREE_TYPE (*expr_p)))
1813 *expr_p = fold_build1_loc (loc, VIEW_CONVERT_EXPR, TREE_TYPE (*expr_p),
1814 TREE_OPERAND (*expr_p, 0));
1819 /* Nonlocal VLAs seen in the current function. */
1820 static struct pointer_set_t *nonlocal_vlas;
1822 /* Gimplify a VAR_DECL or PARM_DECL. Returns GS_OK if we expanded a
1823 DECL_VALUE_EXPR, and it's worth re-examining things. */
1825 static enum gimplify_status
1826 gimplify_var_or_parm_decl (tree *expr_p)
1828 tree decl = *expr_p;
1830 /* ??? If this is a local variable, and it has not been seen in any
1831 outer BIND_EXPR, then it's probably the result of a duplicate
1832 declaration, for which we've already issued an error. It would
1833 be really nice if the front end wouldn't leak these at all.
1834 Currently the only known culprit is C++ destructors, as seen
1835 in g++.old-deja/g++.jason/binding.C. */
1836 if (TREE_CODE (decl) == VAR_DECL
1837 && !DECL_SEEN_IN_BIND_EXPR_P (decl)
1838 && !TREE_STATIC (decl) && !DECL_EXTERNAL (decl)
1839 && decl_function_context (decl) == current_function_decl)
1841 gcc_assert (errorcount || sorrycount);
1845 /* When within an OpenMP context, notice uses of variables. */
1846 if (gimplify_omp_ctxp && omp_notice_variable (gimplify_omp_ctxp, decl, true))
1849 /* If the decl is an alias for another expression, substitute it now. */
1850 if (DECL_HAS_VALUE_EXPR_P (decl))
1852 tree value_expr = DECL_VALUE_EXPR (decl);
1854 /* For referenced nonlocal VLAs add a decl for debugging purposes
1855 to the current function. */
1856 if (TREE_CODE (decl) == VAR_DECL
1857 && TREE_CODE (DECL_SIZE_UNIT (decl)) != INTEGER_CST
1858 && nonlocal_vlas != NULL
1859 && TREE_CODE (value_expr) == INDIRECT_REF
1860 && TREE_CODE (TREE_OPERAND (value_expr, 0)) == VAR_DECL
1861 && decl_function_context (decl) != current_function_decl)
1863 struct gimplify_omp_ctx *ctx = gimplify_omp_ctxp;
1864 while (ctx && ctx->region_type == ORT_WORKSHARE)
1865 ctx = ctx->outer_context;
1866 if (!ctx && !pointer_set_insert (nonlocal_vlas, decl))
1868 tree copy = copy_node (decl), block;
1870 lang_hooks.dup_lang_specific_decl (copy);
1871 SET_DECL_RTL (copy, NULL_RTX);
1872 TREE_USED (copy) = 1;
1873 block = DECL_INITIAL (current_function_decl);
1874 TREE_CHAIN (copy) = BLOCK_VARS (block);
1875 BLOCK_VARS (block) = copy;
1876 SET_DECL_VALUE_EXPR (copy, unshare_expr (value_expr));
1877 DECL_HAS_VALUE_EXPR_P (copy) = 1;
1881 *expr_p = unshare_expr (value_expr);
1889 /* Gimplify the COMPONENT_REF, ARRAY_REF, REALPART_EXPR or IMAGPART_EXPR
1893 : min_lval '[' val ']'
1895 | compound_lval '[' val ']'
1896 | compound_lval '.' ID
1898 This is not part of the original SIMPLE definition, which separates
1899 array and member references, but it seems reasonable to handle them
1900 together. Also, this way we don't run into problems with union
1901 aliasing; gcc requires that for accesses through a union to alias, the
1902 union reference must be explicit, which was not always the case when we
1903 were splitting up array and member refs.
1905 PRE_P points to the sequence where side effects that must happen before
1906 *EXPR_P should be stored.
1908 POST_P points to the sequence where side effects that must happen after
1909 *EXPR_P should be stored. */
1911 static enum gimplify_status
1912 gimplify_compound_lval (tree *expr_p, gimple_seq *pre_p, gimple_seq *post_p,
1913 fallback_t fallback)
1916 VEC(tree,heap) *stack;
1917 enum gimplify_status ret = GS_OK, tret;
1919 location_t loc = EXPR_LOCATION (*expr_p);
1921 /* Create a stack of the subexpressions so later we can walk them in
1922 order from inner to outer. */
1923 stack = VEC_alloc (tree, heap, 10);
1925 /* We can handle anything that get_inner_reference can deal with. */
1926 for (p = expr_p; ; p = &TREE_OPERAND (*p, 0))
1929 /* Fold INDIRECT_REFs now to turn them into ARRAY_REFs. */
1930 if (TREE_CODE (*p) == INDIRECT_REF)
1931 *p = fold_indirect_ref_loc (loc, *p);
1933 if (handled_component_p (*p))
1935 /* Expand DECL_VALUE_EXPR now. In some cases that may expose
1936 additional COMPONENT_REFs. */
1937 else if ((TREE_CODE (*p) == VAR_DECL || TREE_CODE (*p) == PARM_DECL)
1938 && gimplify_var_or_parm_decl (p) == GS_OK)
1943 VEC_safe_push (tree, heap, stack, *p);
1946 gcc_assert (VEC_length (tree, stack));
1948 /* Now STACK is a stack of pointers to all the refs we've walked through
1949 and P points to the innermost expression.
1951 Java requires that we elaborated nodes in source order. That
1952 means we must gimplify the inner expression followed by each of
1953 the indices, in order. But we can't gimplify the inner
1954 expression until we deal with any variable bounds, sizes, or
1955 positions in order to deal with PLACEHOLDER_EXPRs.
1957 So we do this in three steps. First we deal with the annotations
1958 for any variables in the components, then we gimplify the base,
1959 then we gimplify any indices, from left to right. */
1960 for (i = VEC_length (tree, stack) - 1; i >= 0; i--)
1962 tree t = VEC_index (tree, stack, i);
1964 if (TREE_CODE (t) == ARRAY_REF || TREE_CODE (t) == ARRAY_RANGE_REF)
1966 /* Gimplify the low bound and element type size and put them into
1967 the ARRAY_REF. If these values are set, they have already been
1969 if (TREE_OPERAND (t, 2) == NULL_TREE)
1971 tree low = unshare_expr (array_ref_low_bound (t));
1972 if (!is_gimple_min_invariant (low))
1974 TREE_OPERAND (t, 2) = low;
1975 tret = gimplify_expr (&TREE_OPERAND (t, 2), pre_p,
1976 post_p, is_gimple_reg,
1978 ret = MIN (ret, tret);
1982 if (!TREE_OPERAND (t, 3))
1984 tree elmt_type = TREE_TYPE (TREE_TYPE (TREE_OPERAND (t, 0)));
1985 tree elmt_size = unshare_expr (array_ref_element_size (t));
1986 tree factor = size_int (TYPE_ALIGN_UNIT (elmt_type));
1988 /* Divide the element size by the alignment of the element
1990 elmt_size = size_binop_loc (loc, EXACT_DIV_EXPR, elmt_size, factor);
1992 if (!is_gimple_min_invariant (elmt_size))
1994 TREE_OPERAND (t, 3) = elmt_size;
1995 tret = gimplify_expr (&TREE_OPERAND (t, 3), pre_p,
1996 post_p, is_gimple_reg,
1998 ret = MIN (ret, tret);
2002 else if (TREE_CODE (t) == COMPONENT_REF)
2004 /* Set the field offset into T and gimplify it. */
2005 if (!TREE_OPERAND (t, 2))
2007 tree offset = unshare_expr (component_ref_field_offset (t));
2008 tree field = TREE_OPERAND (t, 1);
2010 = size_int (DECL_OFFSET_ALIGN (field) / BITS_PER_UNIT);
2012 /* Divide the offset by its alignment. */
2013 offset = size_binop_loc (loc, EXACT_DIV_EXPR, offset, factor);
2015 if (!is_gimple_min_invariant (offset))
2017 TREE_OPERAND (t, 2) = offset;
2018 tret = gimplify_expr (&TREE_OPERAND (t, 2), pre_p,
2019 post_p, is_gimple_reg,
2021 ret = MIN (ret, tret);
2027 /* Step 2 is to gimplify the base expression. Make sure lvalue is set
2028 so as to match the min_lval predicate. Failure to do so may result
2029 in the creation of large aggregate temporaries. */
2030 tret = gimplify_expr (p, pre_p, post_p, is_gimple_min_lval,
2031 fallback | fb_lvalue);
2032 ret = MIN (ret, tret);
2034 /* And finally, the indices and operands to BIT_FIELD_REF. During this
2035 loop we also remove any useless conversions. */
2036 for (; VEC_length (tree, stack) > 0; )
2038 tree t = VEC_pop (tree, stack);
2040 if (TREE_CODE (t) == ARRAY_REF || TREE_CODE (t) == ARRAY_RANGE_REF)
2042 /* Gimplify the dimension. */
2043 if (!is_gimple_min_invariant (TREE_OPERAND (t, 1)))
2045 tret = gimplify_expr (&TREE_OPERAND (t, 1), pre_p, post_p,
2046 is_gimple_val, fb_rvalue);
2047 ret = MIN (ret, tret);
2050 else if (TREE_CODE (t) == BIT_FIELD_REF)
2052 tret = gimplify_expr (&TREE_OPERAND (t, 1), pre_p, post_p,
2053 is_gimple_val, fb_rvalue);
2054 ret = MIN (ret, tret);
2055 tret = gimplify_expr (&TREE_OPERAND (t, 2), pre_p, post_p,
2056 is_gimple_val, fb_rvalue);
2057 ret = MIN (ret, tret);
2060 STRIP_USELESS_TYPE_CONVERSION (TREE_OPERAND (t, 0));
2062 /* The innermost expression P may have originally had
2063 TREE_SIDE_EFFECTS set which would have caused all the outer
2064 expressions in *EXPR_P leading to P to also have had
2065 TREE_SIDE_EFFECTS set. */
2066 recalculate_side_effects (t);
2069 /* If the outermost expression is a COMPONENT_REF, canonicalize its type. */
2070 if ((fallback & fb_rvalue) && TREE_CODE (*expr_p) == COMPONENT_REF)
2072 canonicalize_component_ref (expr_p);
2073 ret = MIN (ret, GS_OK);
2076 VEC_free (tree, heap, stack);
2081 /* Gimplify the self modifying expression pointed to by EXPR_P
2084 PRE_P points to the list where side effects that must happen before
2085 *EXPR_P should be stored.
2087 POST_P points to the list where side effects that must happen after
2088 *EXPR_P should be stored.
2090 WANT_VALUE is nonzero iff we want to use the value of this expression
2091 in another expression. */
2093 static enum gimplify_status
2094 gimplify_self_mod_expr (tree *expr_p, gimple_seq *pre_p, gimple_seq *post_p,
2097 enum tree_code code;
2098 tree lhs, lvalue, rhs, t1;
2099 gimple_seq post = NULL, *orig_post_p = post_p;
2101 enum tree_code arith_code;
2102 enum gimplify_status ret;
2103 location_t loc = EXPR_LOCATION (*expr_p);
2105 code = TREE_CODE (*expr_p);
2107 gcc_assert (code == POSTINCREMENT_EXPR || code == POSTDECREMENT_EXPR
2108 || code == PREINCREMENT_EXPR || code == PREDECREMENT_EXPR);
2110 /* Prefix or postfix? */
2111 if (code == POSTINCREMENT_EXPR || code == POSTDECREMENT_EXPR)
2112 /* Faster to treat as prefix if result is not used. */
2113 postfix = want_value;
2117 /* For postfix, make sure the inner expression's post side effects
2118 are executed after side effects from this expression. */
2122 /* Add or subtract? */
2123 if (code == PREINCREMENT_EXPR || code == POSTINCREMENT_EXPR)
2124 arith_code = PLUS_EXPR;
2126 arith_code = MINUS_EXPR;
2128 /* Gimplify the LHS into a GIMPLE lvalue. */
2129 lvalue = TREE_OPERAND (*expr_p, 0);
2130 ret = gimplify_expr (&lvalue, pre_p, post_p, is_gimple_lvalue, fb_lvalue);
2131 if (ret == GS_ERROR)
2134 /* Extract the operands to the arithmetic operation. */
2136 rhs = TREE_OPERAND (*expr_p, 1);
2138 /* For postfix operator, we evaluate the LHS to an rvalue and then use
2139 that as the result value and in the postqueue operation. We also
2140 make sure to make lvalue a minimal lval, see
2141 gcc.c-torture/execute/20040313-1.c for an example where this matters. */
2144 if (!is_gimple_min_lval (lvalue))
2146 mark_addressable (lvalue);
2147 lvalue = build_fold_addr_expr_loc (input_location, lvalue);
2148 gimplify_expr (&lvalue, pre_p, post_p, is_gimple_val, fb_rvalue);
2149 lvalue = build_fold_indirect_ref_loc (input_location, lvalue);
2151 ret = gimplify_expr (&lhs, pre_p, post_p, is_gimple_val, fb_rvalue);
2152 if (ret == GS_ERROR)
2156 /* For POINTERs increment, use POINTER_PLUS_EXPR. */
2157 if (POINTER_TYPE_P (TREE_TYPE (lhs)))
2159 rhs = fold_convert_loc (loc, sizetype, rhs);
2160 if (arith_code == MINUS_EXPR)
2161 rhs = fold_build1_loc (loc, NEGATE_EXPR, TREE_TYPE (rhs), rhs);
2162 arith_code = POINTER_PLUS_EXPR;
2165 t1 = build2 (arith_code, TREE_TYPE (*expr_p), lhs, rhs);
2169 gimplify_assign (lvalue, t1, orig_post_p);
2170 gimplify_seq_add_seq (orig_post_p, post);
2176 *expr_p = build2 (MODIFY_EXPR, TREE_TYPE (lvalue), lvalue, t1);
2182 /* If *EXPR_P has a variable sized type, wrap it in a WITH_SIZE_EXPR. */
2185 maybe_with_size_expr (tree *expr_p)
2187 tree expr = *expr_p;
2188 tree type = TREE_TYPE (expr);
2191 /* If we've already wrapped this or the type is error_mark_node, we can't do
2193 if (TREE_CODE (expr) == WITH_SIZE_EXPR
2194 || type == error_mark_node)
2197 /* If the size isn't known or is a constant, we have nothing to do. */
2198 size = TYPE_SIZE_UNIT (type);
2199 if (!size || TREE_CODE (size) == INTEGER_CST)
2202 /* Otherwise, make a WITH_SIZE_EXPR. */
2203 size = unshare_expr (size);
2204 size = SUBSTITUTE_PLACEHOLDER_IN_EXPR (size, expr);
2205 *expr_p = build2 (WITH_SIZE_EXPR, type, expr, size);
2209 /* Helper for gimplify_call_expr. Gimplify a single argument *ARG_P
2210 Store any side-effects in PRE_P. CALL_LOCATION is the location of
2213 static enum gimplify_status
2214 gimplify_arg (tree *arg_p, gimple_seq *pre_p, location_t call_location)
2216 bool (*test) (tree);
2219 /* In general, we allow lvalues for function arguments to avoid
2220 extra overhead of copying large aggregates out of even larger
2221 aggregates into temporaries only to copy the temporaries to
2222 the argument list. Make optimizers happy by pulling out to
2223 temporaries those types that fit in registers. */
2224 if (is_gimple_reg_type (TREE_TYPE (*arg_p)))
2225 test = is_gimple_val, fb = fb_rvalue;
2227 test = is_gimple_lvalue, fb = fb_either;
2229 /* If this is a variable sized type, we must remember the size. */
2230 maybe_with_size_expr (arg_p);
2232 /* FIXME diagnostics: This will mess up gcc.dg/Warray-bounds.c. */
2233 /* Make sure arguments have the same location as the function call
2235 protected_set_expr_location (*arg_p, call_location);
2237 /* There is a sequence point before a function call. Side effects in
2238 the argument list must occur before the actual call. So, when
2239 gimplifying arguments, force gimplify_expr to use an internal
2240 post queue which is then appended to the end of PRE_P. */
2241 return gimplify_expr (arg_p, pre_p, NULL, test, fb);
2245 /* Gimplify the CALL_EXPR node *EXPR_P into the GIMPLE sequence PRE_P.
2246 WANT_VALUE is true if the result of the call is desired. */
2248 static enum gimplify_status
2249 gimplify_call_expr (tree *expr_p, gimple_seq *pre_p, bool want_value)
2251 tree fndecl, parms, p;
2252 enum gimplify_status ret;
2255 bool builtin_va_start_p = FALSE;
2256 location_t loc = EXPR_LOCATION (*expr_p);
2258 gcc_assert (TREE_CODE (*expr_p) == CALL_EXPR);
2260 /* For reliable diagnostics during inlining, it is necessary that
2261 every call_expr be annotated with file and line. */
2262 if (! EXPR_HAS_LOCATION (*expr_p))
2263 SET_EXPR_LOCATION (*expr_p, input_location);
2265 /* This may be a call to a builtin function.
2267 Builtin function calls may be transformed into different
2268 (and more efficient) builtin function calls under certain
2269 circumstances. Unfortunately, gimplification can muck things
2270 up enough that the builtin expanders are not aware that certain
2271 transformations are still valid.
2273 So we attempt transformation/gimplification of the call before
2274 we gimplify the CALL_EXPR. At this time we do not manage to
2275 transform all calls in the same manner as the expanders do, but
2276 we do transform most of them. */
2277 fndecl = get_callee_fndecl (*expr_p);
2278 if (fndecl && DECL_BUILT_IN (fndecl))
2280 tree new_tree = fold_call_expr (input_location, *expr_p, !want_value);
2282 if (new_tree && new_tree != *expr_p)
2284 /* There was a transformation of this call which computes the
2285 same value, but in a more efficient way. Return and try
2291 if (DECL_BUILT_IN_CLASS (fndecl) == BUILT_IN_NORMAL
2292 && DECL_FUNCTION_CODE (fndecl) == BUILT_IN_VA_START)
2294 builtin_va_start_p = TRUE;
2295 if (call_expr_nargs (*expr_p) < 2)
2297 error ("too few arguments to function %<va_start%>");
2298 *expr_p = build_empty_stmt (EXPR_LOCATION (*expr_p));
2302 if (fold_builtin_next_arg (*expr_p, true))
2304 *expr_p = build_empty_stmt (EXPR_LOCATION (*expr_p));
2310 /* There is a sequence point before the call, so any side effects in
2311 the calling expression must occur before the actual call. Force
2312 gimplify_expr to use an internal post queue. */
2313 ret = gimplify_expr (&CALL_EXPR_FN (*expr_p), pre_p, NULL,
2314 is_gimple_call_addr, fb_rvalue);
2316 nargs = call_expr_nargs (*expr_p);
2318 /* Get argument types for verification. */
2319 fndecl = get_callee_fndecl (*expr_p);
2322 parms = TYPE_ARG_TYPES (TREE_TYPE (fndecl));
2323 else if (POINTER_TYPE_P (TREE_TYPE (CALL_EXPR_FN (*expr_p))))
2324 parms = TYPE_ARG_TYPES (TREE_TYPE (TREE_TYPE (CALL_EXPR_FN (*expr_p))));
2326 if (fndecl && DECL_ARGUMENTS (fndecl))
2327 p = DECL_ARGUMENTS (fndecl);
2332 for (i = 0; i < nargs && p; i++, p = TREE_CHAIN (p))
2335 /* If the last argument is __builtin_va_arg_pack () and it is not
2336 passed as a named argument, decrease the number of CALL_EXPR
2337 arguments and set instead the CALL_EXPR_VA_ARG_PACK flag. */
2340 && TREE_CODE (CALL_EXPR_ARG (*expr_p, nargs - 1)) == CALL_EXPR)
2342 tree last_arg = CALL_EXPR_ARG (*expr_p, nargs - 1);
2343 tree last_arg_fndecl = get_callee_fndecl (last_arg);
2346 && TREE_CODE (last_arg_fndecl) == FUNCTION_DECL
2347 && DECL_BUILT_IN_CLASS (last_arg_fndecl) == BUILT_IN_NORMAL
2348 && DECL_FUNCTION_CODE (last_arg_fndecl) == BUILT_IN_VA_ARG_PACK)
2350 tree call = *expr_p;
2353 *expr_p = build_call_array_loc (loc, TREE_TYPE (call),
2354 CALL_EXPR_FN (call),
2355 nargs, CALL_EXPR_ARGP (call));
2357 /* Copy all CALL_EXPR flags, location and block, except
2358 CALL_EXPR_VA_ARG_PACK flag. */
2359 CALL_EXPR_STATIC_CHAIN (*expr_p) = CALL_EXPR_STATIC_CHAIN (call);
2360 CALL_EXPR_TAILCALL (*expr_p) = CALL_EXPR_TAILCALL (call);
2361 CALL_EXPR_RETURN_SLOT_OPT (*expr_p)
2362 = CALL_EXPR_RETURN_SLOT_OPT (call);
2363 CALL_FROM_THUNK_P (*expr_p) = CALL_FROM_THUNK_P (call);
2364 CALL_CANNOT_INLINE_P (*expr_p) = CALL_CANNOT_INLINE_P (call);
2365 SET_EXPR_LOCATION (*expr_p, EXPR_LOCATION (call));
2366 TREE_BLOCK (*expr_p) = TREE_BLOCK (call);
2368 /* Set CALL_EXPR_VA_ARG_PACK. */
2369 CALL_EXPR_VA_ARG_PACK (*expr_p) = 1;
2373 /* Finally, gimplify the function arguments. */
2376 for (i = (PUSH_ARGS_REVERSED ? nargs - 1 : 0);
2377 PUSH_ARGS_REVERSED ? i >= 0 : i < nargs;
2378 PUSH_ARGS_REVERSED ? i-- : i++)
2380 enum gimplify_status t;
2382 /* Avoid gimplifying the second argument to va_start, which needs to
2383 be the plain PARM_DECL. */
2384 if ((i != 1) || !builtin_va_start_p)
2386 t = gimplify_arg (&CALL_EXPR_ARG (*expr_p, i), pre_p,
2387 EXPR_LOCATION (*expr_p));
2395 /* Verify the function result. */
2396 if (want_value && fndecl
2397 && VOID_TYPE_P (TREE_TYPE (TREE_TYPE (fndecl))))
2399 error_at (loc, "using result of function returning %<void%>");
2403 /* Try this again in case gimplification exposed something. */
2404 if (ret != GS_ERROR)
2406 tree new_tree = fold_call_expr (input_location, *expr_p, !want_value);
2408 if (new_tree && new_tree != *expr_p)
2410 /* There was a transformation of this call which computes the
2411 same value, but in a more efficient way. Return and try
2419 *expr_p = error_mark_node;
2423 /* If the function is "const" or "pure", then clear TREE_SIDE_EFFECTS on its
2424 decl. This allows us to eliminate redundant or useless
2425 calls to "const" functions. */
2426 if (TREE_CODE (*expr_p) == CALL_EXPR)
2428 int flags = call_expr_flags (*expr_p);
2429 if (flags & (ECF_CONST | ECF_PURE)
2430 /* An infinite loop is considered a side effect. */
2431 && !(flags & (ECF_LOOPING_CONST_OR_PURE)))
2432 TREE_SIDE_EFFECTS (*expr_p) = 0;
2435 /* If the value is not needed by the caller, emit a new GIMPLE_CALL
2436 and clear *EXPR_P. Otherwise, leave *EXPR_P in its gimplified
2437 form and delegate the creation of a GIMPLE_CALL to
2438 gimplify_modify_expr. This is always possible because when
2439 WANT_VALUE is true, the caller wants the result of this call into
2440 a temporary, which means that we will emit an INIT_EXPR in
2441 internal_get_tmp_var which will then be handled by
2442 gimplify_modify_expr. */
2445 /* The CALL_EXPR in *EXPR_P is already in GIMPLE form, so all we
2446 have to do is replicate it as a GIMPLE_CALL tuple. */
2447 call = gimple_build_call_from_tree (*expr_p);
2448 gimplify_seq_add_stmt (pre_p, call);
2449 *expr_p = NULL_TREE;
2455 /* Handle shortcut semantics in the predicate operand of a COND_EXPR by
2456 rewriting it into multiple COND_EXPRs, and possibly GOTO_EXPRs.
2458 TRUE_LABEL_P and FALSE_LABEL_P point to the labels to jump to if the
2459 condition is true or false, respectively. If null, we should generate
2460 our own to skip over the evaluation of this specific expression.
2462 LOCUS is the source location of the COND_EXPR.
2464 This function is the tree equivalent of do_jump.
2466 shortcut_cond_r should only be called by shortcut_cond_expr. */
2469 shortcut_cond_r (tree pred, tree *true_label_p, tree *false_label_p,
2472 tree local_label = NULL_TREE;
2473 tree t, expr = NULL;
2475 /* OK, it's not a simple case; we need to pull apart the COND_EXPR to
2476 retain the shortcut semantics. Just insert the gotos here;
2477 shortcut_cond_expr will append the real blocks later. */
2478 if (TREE_CODE (pred) == TRUTH_ANDIF_EXPR)
2480 location_t new_locus;
2482 /* Turn if (a && b) into
2484 if (a); else goto no;
2485 if (b) goto yes; else goto no;
2488 if (false_label_p == NULL)
2489 false_label_p = &local_label;
2491 /* Keep the original source location on the first 'if'. */
2492 t = shortcut_cond_r (TREE_OPERAND (pred, 0), NULL, false_label_p, locus);
2493 append_to_statement_list (t, &expr);
2495 /* Set the source location of the && on the second 'if'. */
2496 new_locus = EXPR_HAS_LOCATION (pred) ? EXPR_LOCATION (pred) : locus;
2497 t = shortcut_cond_r (TREE_OPERAND (pred, 1), true_label_p, false_label_p,
2499 append_to_statement_list (t, &expr);
2501 else if (TREE_CODE (pred) == TRUTH_ORIF_EXPR)
2503 location_t new_locus;
2505 /* Turn if (a || b) into
2508 if (b) goto yes; else goto no;
2511 if (true_label_p == NULL)
2512 true_label_p = &local_label;
2514 /* Keep the original source location on the first 'if'. */
2515 t = shortcut_cond_r (TREE_OPERAND (pred, 0), true_label_p, NULL, locus);
2516 append_to_statement_list (t, &expr);
2518 /* Set the source location of the || on the second 'if'. */
2519 new_locus = EXPR_HAS_LOCATION (pred) ? EXPR_LOCATION (pred) : locus;
2520 t = shortcut_cond_r (TREE_OPERAND (pred, 1), true_label_p, false_label_p,
2522 append_to_statement_list (t, &expr);
2524 else if (TREE_CODE (pred) == COND_EXPR)
2526 location_t new_locus;
2528 /* As long as we're messing with gotos, turn if (a ? b : c) into
2530 if (b) goto yes; else goto no;
2532 if (c) goto yes; else goto no; */
2534 /* Keep the original source location on the first 'if'. Set the source
2535 location of the ? on the second 'if'. */
2536 new_locus = EXPR_HAS_LOCATION (pred) ? EXPR_LOCATION (pred) : locus;
2537 expr = build3 (COND_EXPR, void_type_node, TREE_OPERAND (pred, 0),
2538 shortcut_cond_r (TREE_OPERAND (pred, 1), true_label_p,
2539 false_label_p, locus),
2540 shortcut_cond_r (TREE_OPERAND (pred, 2), true_label_p,
2541 false_label_p, new_locus));
2545 expr = build3 (COND_EXPR, void_type_node, pred,
2546 build_and_jump (true_label_p),
2547 build_and_jump (false_label_p));
2548 SET_EXPR_LOCATION (expr, locus);
2553 t = build1 (LABEL_EXPR, void_type_node, local_label);
2554 append_to_statement_list (t, &expr);
2560 /* Given a conditional expression EXPR with short-circuit boolean
2561 predicates using TRUTH_ANDIF_EXPR or TRUTH_ORIF_EXPR, break the
2562 predicate appart into the equivalent sequence of conditionals. */
2565 shortcut_cond_expr (tree expr)
2567 tree pred = TREE_OPERAND (expr, 0);
2568 tree then_ = TREE_OPERAND (expr, 1);
2569 tree else_ = TREE_OPERAND (expr, 2);
2570 tree true_label, false_label, end_label, t;
2572 tree *false_label_p;
2573 bool emit_end, emit_false, jump_over_else;
2574 bool then_se = then_ && TREE_SIDE_EFFECTS (then_);
2575 bool else_se = else_ && TREE_SIDE_EFFECTS (else_);
2577 /* First do simple transformations. */
2580 /* If there is no 'else', turn
2583 if (a) if (b) then c. */
2584 while (TREE_CODE (pred) == TRUTH_ANDIF_EXPR)
2586 /* Keep the original source location on the first 'if'. */
2587 location_t locus = EXPR_HAS_LOCATION (expr)
2588 ? EXPR_LOCATION (expr) : input_location;
2589 TREE_OPERAND (expr, 0) = TREE_OPERAND (pred, 1);
2590 /* Set the source location of the && on the second 'if'. */
2591 if (EXPR_HAS_LOCATION (pred))
2592 SET_EXPR_LOCATION (expr, EXPR_LOCATION (pred));
2593 then_ = shortcut_cond_expr (expr);
2594 then_se = then_ && TREE_SIDE_EFFECTS (then_);
2595 pred = TREE_OPERAND (pred, 0);
2596 expr = build3 (COND_EXPR, void_type_node, pred, then_, NULL_TREE);
2597 SET_EXPR_LOCATION (expr, locus);
2603 /* If there is no 'then', turn
2606 if (a); else if (b); else d. */
2607 while (TREE_CODE (pred) == TRUTH_ORIF_EXPR)
2609 /* Keep the original source location on the first 'if'. */
2610 location_t locus = EXPR_HAS_LOCATION (expr)
2611 ? EXPR_LOCATION (expr) : input_location;
2612 TREE_OPERAND (expr, 0) = TREE_OPERAND (pred, 1);
2613 /* Set the source location of the || on the second 'if'. */
2614 if (EXPR_HAS_LOCATION (pred))
2615 SET_EXPR_LOCATION (expr, EXPR_LOCATION (pred));
2616 else_ = shortcut_cond_expr (expr);
2617 else_se = else_ && TREE_SIDE_EFFECTS (else_);
2618 pred = TREE_OPERAND (pred, 0);
2619 expr = build3 (COND_EXPR, void_type_node, pred, NULL_TREE, else_);
2620 SET_EXPR_LOCATION (expr, locus);
2624 /* If we're done, great. */
2625 if (TREE_CODE (pred) != TRUTH_ANDIF_EXPR
2626 && TREE_CODE (pred) != TRUTH_ORIF_EXPR)
2629 /* Otherwise we need to mess with gotos. Change
2632 if (a); else goto no;
2635 and recursively gimplify the condition. */
2637 true_label = false_label = end_label = NULL_TREE;
2639 /* If our arms just jump somewhere, hijack those labels so we don't
2640 generate jumps to jumps. */
2643 && TREE_CODE (then_) == GOTO_EXPR
2644 && TREE_CODE (GOTO_DESTINATION (then_)) == LABEL_DECL)
2646 true_label = GOTO_DESTINATION (then_);
2652 && TREE_CODE (else_) == GOTO_EXPR
2653 && TREE_CODE (GOTO_DESTINATION (else_)) == LABEL_DECL)
2655 false_label = GOTO_DESTINATION (else_);
2660 /* If we aren't hijacking a label for the 'then' branch, it falls through. */
2662 true_label_p = &true_label;
2664 true_label_p = NULL;
2666 /* The 'else' branch also needs a label if it contains interesting code. */
2667 if (false_label || else_se)
2668 false_label_p = &false_label;
2670 false_label_p = NULL;
2672 /* If there was nothing else in our arms, just forward the label(s). */
2673 if (!then_se && !else_se)
2674 return shortcut_cond_r (pred, true_label_p, false_label_p,
2675 EXPR_HAS_LOCATION (expr)
2676 ? EXPR_LOCATION (expr) : input_location);
2678 /* If our last subexpression already has a terminal label, reuse it. */
2680 t = expr_last (else_);
2682 t = expr_last (then_);
2685 if (t && TREE_CODE (t) == LABEL_EXPR)
2686 end_label = LABEL_EXPR_LABEL (t);
2688 /* If we don't care about jumping to the 'else' branch, jump to the end
2689 if the condition is false. */
2691 false_label_p = &end_label;
2693 /* We only want to emit these labels if we aren't hijacking them. */
2694 emit_end = (end_label == NULL_TREE);
2695 emit_false = (false_label == NULL_TREE);
2697 /* We only emit the jump over the else clause if we have to--if the
2698 then clause may fall through. Otherwise we can wind up with a
2699 useless jump and a useless label at the end of gimplified code,
2700 which will cause us to think that this conditional as a whole
2701 falls through even if it doesn't. If we then inline a function
2702 which ends with such a condition, that can cause us to issue an
2703 inappropriate warning about control reaching the end of a
2704 non-void function. */
2705 jump_over_else = block_may_fallthru (then_);
2707 pred = shortcut_cond_r (pred, true_label_p, false_label_p,
2708 EXPR_HAS_LOCATION (expr)
2709 ? EXPR_LOCATION (expr) : input_location);
2712 append_to_statement_list (pred, &expr);
2714 append_to_statement_list (then_, &expr);
2719 tree last = expr_last (expr);
2720 t = build_and_jump (&end_label);
2721 if (EXPR_HAS_LOCATION (last))
2722 SET_EXPR_LOCATION (t, EXPR_LOCATION (last));
2723 append_to_statement_list (t, &expr);
2727 t = build1 (LABEL_EXPR, void_type_node, false_label);
2728 append_to_statement_list (t, &expr);
2730 append_to_statement_list (else_, &expr);
2732 if (emit_end && end_label)
2734 t = build1 (LABEL_EXPR, void_type_node, end_label);
2735 append_to_statement_list (t, &expr);
2741 /* EXPR is used in a boolean context; make sure it has BOOLEAN_TYPE. */
2744 gimple_boolify (tree expr)
2746 tree type = TREE_TYPE (expr);
2747 location_t loc = EXPR_LOCATION (expr);
2749 if (TREE_CODE (expr) == NE_EXPR
2750 && TREE_CODE (TREE_OPERAND (expr, 0)) == CALL_EXPR
2751 && integer_zerop (TREE_OPERAND (expr, 1)))
2753 tree call = TREE_OPERAND (expr, 0);
2754 tree fn = get_callee_fndecl (call);
2756 /* For __builtin_expect ((long) (x), y) recurse into x as well
2757 if x is truth_value_p. */
2759 && DECL_BUILT_IN_CLASS (fn) == BUILT_IN_NORMAL
2760 && DECL_FUNCTION_CODE (fn) == BUILT_IN_EXPECT
2761 && call_expr_nargs (call) == 2)
2763 tree arg = CALL_EXPR_ARG (call, 0);
2766 if (TREE_CODE (arg) == NOP_EXPR
2767 && TREE_TYPE (arg) == TREE_TYPE (call))
2768 arg = TREE_OPERAND (arg, 0);
2769 if (truth_value_p (TREE_CODE (arg)))
2771 arg = gimple_boolify (arg);
2772 CALL_EXPR_ARG (call, 0)
2773 = fold_convert_loc (loc, TREE_TYPE (call), arg);
2779 if (TREE_CODE (type) == BOOLEAN_TYPE)
2782 switch (TREE_CODE (expr))
2784 case TRUTH_AND_EXPR:
2786 case TRUTH_XOR_EXPR:
2787 case TRUTH_ANDIF_EXPR:
2788 case TRUTH_ORIF_EXPR:
2789 /* Also boolify the arguments of truth exprs. */
2790 TREE_OPERAND (expr, 1) = gimple_boolify (TREE_OPERAND (expr, 1));
2793 case TRUTH_NOT_EXPR:
2794 TREE_OPERAND (expr, 0) = gimple_boolify (TREE_OPERAND (expr, 0));
2797 case EQ_EXPR: case NE_EXPR:
2798 case LE_EXPR: case GE_EXPR: case LT_EXPR: case GT_EXPR:
2799 /* These expressions always produce boolean results. */
2800 TREE_TYPE (expr) = boolean_type_node;
2804 /* Other expressions that get here must have boolean values, but
2805 might need to be converted to the appropriate mode. */
2806 return fold_convert_loc (loc, boolean_type_node, expr);
2810 /* Given a conditional expression *EXPR_P without side effects, gimplify
2811 its operands. New statements are inserted to PRE_P. */
2813 static enum gimplify_status
2814 gimplify_pure_cond_expr (tree *expr_p, gimple_seq *pre_p)
2816 tree expr = *expr_p, cond;
2817 enum gimplify_status ret, tret;
2818 enum tree_code code;
2820 cond = gimple_boolify (COND_EXPR_COND (expr));
2822 /* We need to handle && and || specially, as their gimplification
2823 creates pure cond_expr, thus leading to an infinite cycle otherwise. */
2824 code = TREE_CODE (cond);
2825 if (code == TRUTH_ANDIF_EXPR)
2826 TREE_SET_CODE (cond, TRUTH_AND_EXPR);
2827 else if (code == TRUTH_ORIF_EXPR)
2828 TREE_SET_CODE (cond, TRUTH_OR_EXPR);
2829 ret = gimplify_expr (&cond, pre_p, NULL, is_gimple_condexpr, fb_rvalue);
2830 COND_EXPR_COND (*expr_p) = cond;
2832 tret = gimplify_expr (&COND_EXPR_THEN (expr), pre_p, NULL,
2833 is_gimple_val, fb_rvalue);
2834 ret = MIN (ret, tret);
2835 tret = gimplify_expr (&COND_EXPR_ELSE (expr), pre_p, NULL,
2836 is_gimple_val, fb_rvalue);
2838 return MIN (ret, tret);
2841 /* Returns true if evaluating EXPR could trap.
2842 EXPR is GENERIC, while tree_could_trap_p can be called
2846 generic_expr_could_trap_p (tree expr)
2850 if (!expr || is_gimple_val (expr))
2853 if (!EXPR_P (expr) || tree_could_trap_p (expr))
2856 n = TREE_OPERAND_LENGTH (expr);
2857 for (i = 0; i < n; i++)
2858 if (generic_expr_could_trap_p (TREE_OPERAND (expr, i)))
2864 /* Convert the conditional expression pointed to by EXPR_P '(p) ? a : b;'
2873 The second form is used when *EXPR_P is of type void.
2875 PRE_P points to the list where side effects that must happen before
2876 *EXPR_P should be stored. */
2878 static enum gimplify_status
2879 gimplify_cond_expr (tree *expr_p, gimple_seq *pre_p, fallback_t fallback)
2881 tree expr = *expr_p;
2882 tree type = TREE_TYPE (expr);
2883 location_t loc = EXPR_LOCATION (expr);
2884 tree tmp, arm1, arm2;
2885 enum gimplify_status ret;
2886 tree label_true, label_false, label_cont;
2887 bool have_then_clause_p, have_else_clause_p;
2889 enum tree_code pred_code;
2890 gimple_seq seq = NULL;
2892 /* If this COND_EXPR has a value, copy the values into a temporary within
2894 if (!VOID_TYPE_P (type))
2896 tree then_ = TREE_OPERAND (expr, 1), else_ = TREE_OPERAND (expr, 2);
2899 /* If either an rvalue is ok or we do not require an lvalue, create the
2900 temporary. But we cannot do that if the type is addressable. */
2901 if (((fallback & fb_rvalue) || !(fallback & fb_lvalue))
2902 && !TREE_ADDRESSABLE (type))
2904 if (gimplify_ctxp->allow_rhs_cond_expr
2905 /* If either branch has side effects or could trap, it can't be
2906 evaluated unconditionally. */
2907 && !TREE_SIDE_EFFECTS (then_)
2908 && !generic_expr_could_trap_p (then_)
2909 && !TREE_SIDE_EFFECTS (else_)
2910 && !generic_expr_could_trap_p (else_))
2911 return gimplify_pure_cond_expr (expr_p, pre_p);
2913 tmp = create_tmp_var (type, "iftmp");
2917 /* Otherwise, only create and copy references to the values. */
2920 type = build_pointer_type (type);
2922 if (!VOID_TYPE_P (TREE_TYPE (then_)))
2923 then_ = build_fold_addr_expr_loc (loc, then_);
2925 if (!VOID_TYPE_P (TREE_TYPE (else_)))
2926 else_ = build_fold_addr_expr_loc (loc, else_);
2929 = build3 (COND_EXPR, type, TREE_OPERAND (expr, 0), then_, else_);
2931 tmp = create_tmp_var (type, "iftmp");
2932 result = build_fold_indirect_ref_loc (loc, tmp);
2935 /* Build the new then clause, `tmp = then_;'. But don't build the
2936 assignment if the value is void; in C++ it can be if it's a throw. */
2937 if (!VOID_TYPE_P (TREE_TYPE (then_)))
2938 TREE_OPERAND (expr, 1) = build2 (MODIFY_EXPR, type, tmp, then_);
2940 /* Similarly, build the new else clause, `tmp = else_;'. */
2941 if (!VOID_TYPE_P (TREE_TYPE (else_)))
2942 TREE_OPERAND (expr, 2) = build2 (MODIFY_EXPR, type, tmp, else_);
2944 TREE_TYPE (expr) = void_type_node;
2945 recalculate_side_effects (expr);
2947 /* Move the COND_EXPR to the prequeue. */
2948 gimplify_stmt (&expr, pre_p);
2954 /* Make sure the condition has BOOLEAN_TYPE. */
2955 TREE_OPERAND (expr, 0) = gimple_boolify (TREE_OPERAND (expr, 0));
2957 /* Break apart && and || conditions. */
2958 if (TREE_CODE (TREE_OPERAND (expr, 0)) == TRUTH_ANDIF_EXPR
2959 || TREE_CODE (TREE_OPERAND (expr, 0)) == TRUTH_ORIF_EXPR)
2961 expr = shortcut_cond_expr (expr);
2963 if (expr != *expr_p)
2967 /* We can't rely on gimplify_expr to re-gimplify the expanded
2968 form properly, as cleanups might cause the target labels to be
2969 wrapped in a TRY_FINALLY_EXPR. To prevent that, we need to
2970 set up a conditional context. */
2971 gimple_push_condition ();
2972 gimplify_stmt (expr_p, &seq);
2973 gimple_pop_condition (pre_p);
2974 gimple_seq_add_seq (pre_p, seq);
2980 /* Now do the normal gimplification. */
2982 /* Gimplify condition. */
2983 ret = gimplify_expr (&TREE_OPERAND (expr, 0), pre_p, NULL, is_gimple_condexpr,
2985 if (ret == GS_ERROR)
2987 gcc_assert (TREE_OPERAND (expr, 0) != NULL_TREE);
2989 gimple_push_condition ();
2991 have_then_clause_p = have_else_clause_p = false;
2992 if (TREE_OPERAND (expr, 1) != NULL
2993 && TREE_CODE (TREE_OPERAND (expr, 1)) == GOTO_EXPR
2994 && TREE_CODE (GOTO_DESTINATION (TREE_OPERAND (expr, 1))) == LABEL_DECL
2995 && (DECL_CONTEXT (GOTO_DESTINATION (TREE_OPERAND (expr, 1)))
2996 == current_function_decl)
2997 /* For -O0 avoid this optimization if the COND_EXPR and GOTO_EXPR
2998 have different locations, otherwise we end up with incorrect
2999 location information on the branches. */
3001 || !EXPR_HAS_LOCATION (expr)
3002 || !EXPR_HAS_LOCATION (TREE_OPERAND (expr, 1))
3003 || EXPR_LOCATION (expr) == EXPR_LOCATION (TREE_OPERAND (expr, 1))))
3005 label_true = GOTO_DESTINATION (TREE_OPERAND (expr, 1));
3006 have_then_clause_p = true;
3009 label_true = create_artificial_label (UNKNOWN_LOCATION);
3010 if (TREE_OPERAND (expr, 2) != NULL
3011 && TREE_CODE (TREE_OPERAND (expr, 2)) == GOTO_EXPR
3012 && TREE_CODE (GOTO_DESTINATION (TREE_OPERAND (expr, 2))) == LABEL_DECL
3013 && (DECL_CONTEXT (GOTO_DESTINATION (TREE_OPERAND (expr, 2)))
3014 == current_function_decl)
3015 /* For -O0 avoid this optimization if the COND_EXPR and GOTO_EXPR
3016 have different locations, otherwise we end up with incorrect
3017 location information on the branches. */
3019 || !EXPR_HAS_LOCATION (expr)
3020 || !EXPR_HAS_LOCATION (TREE_OPERAND (expr, 2))
3021 || EXPR_LOCATION (expr) == EXPR_LOCATION (TREE_OPERAND (expr, 2))))
3023 label_false = GOTO_DESTINATION (TREE_OPERAND (expr, 2));
3024 have_else_clause_p = true;
3027 label_false = create_artificial_label (UNKNOWN_LOCATION);
3029 gimple_cond_get_ops_from_tree (COND_EXPR_COND (expr), &pred_code, &arm1,
3032 gimple_cond = gimple_build_cond (pred_code, arm1, arm2, label_true,
3035 gimplify_seq_add_stmt (&seq, gimple_cond);
3036 label_cont = NULL_TREE;
3037 if (!have_then_clause_p)
3039 /* For if (...) {} else { code; } put label_true after
3041 if (TREE_OPERAND (expr, 1) == NULL_TREE
3042 && !have_else_clause_p
3043 && TREE_OPERAND (expr, 2) != NULL_TREE)
3044 label_cont = label_true;
3047 gimplify_seq_add_stmt (&seq, gimple_build_label (label_true));
3048 have_then_clause_p = gimplify_stmt (&TREE_OPERAND (expr, 1), &seq);
3049 /* For if (...) { code; } else {} or
3050 if (...) { code; } else goto label; or
3051 if (...) { code; return; } else { ... }
3052 label_cont isn't needed. */
3053 if (!have_else_clause_p
3054 && TREE_OPERAND (expr, 2) != NULL_TREE
3055 && gimple_seq_may_fallthru (seq))
3058 label_cont = create_artificial_label (UNKNOWN_LOCATION);
3060 g = gimple_build_goto (label_cont);
3062 /* GIMPLE_COND's are very low level; they have embedded
3063 gotos. This particular embedded goto should not be marked
3064 with the location of the original COND_EXPR, as it would
3065 correspond to the COND_EXPR's condition, not the ELSE or the
3066 THEN arms. To avoid marking it with the wrong location, flag
3067 it as "no location". */
3068 gimple_set_do_not_emit_location (g);
3070 gimplify_seq_add_stmt (&seq, g);
3074 if (!have_else_clause_p)
3076 gimplify_seq_add_stmt (&seq, gimple_build_label (label_false));
3077 have_else_clause_p = gimplify_stmt (&TREE_OPERAND (expr, 2), &seq);
3080 gimplify_seq_add_stmt (&seq, gimple_build_label (label_cont));
3082 gimple_pop_condition (pre_p);
3083 gimple_seq_add_seq (pre_p, seq);
3085 if (ret == GS_ERROR)
3087 else if (have_then_clause_p || have_else_clause_p)
3091 /* Both arms are empty; replace the COND_EXPR with its predicate. */
3092 expr = TREE_OPERAND (expr, 0);
3093 gimplify_stmt (&expr, pre_p);
3100 /* Prepare the node pointed to by EXPR_P, an is_gimple_addressable expression,
3101 to be marked addressable.
3103 We cannot rely on such an expression being directly markable if a temporary
3104 has been created by the gimplification. In this case, we create another
3105 temporary and initialize it with a copy, which will become a store after we
3106 mark it addressable. This can happen if the front-end passed us something
3107 that it could not mark addressable yet, like a Fortran pass-by-reference
3108 parameter (int) floatvar. */
3111 prepare_gimple_addressable (tree *expr_p, gimple_seq *seq_p)
3113 while (handled_component_p (*expr_p))
3114 expr_p = &TREE_OPERAND (*expr_p, 0);
3115 if (is_gimple_reg (*expr_p))
3116 *expr_p = get_initialized_tmp_var (*expr_p, seq_p, NULL);
3119 /* A subroutine of gimplify_modify_expr. Replace a MODIFY_EXPR with
3120 a call to __builtin_memcpy. */
3122 static enum gimplify_status
3123 gimplify_modify_expr_to_memcpy (tree *expr_p, tree size, bool want_value,
3126 tree t, to, to_ptr, from, from_ptr;
3128 location_t loc = EXPR_LOCATION (*expr_p);
3130 to = TREE_OPERAND (*expr_p, 0);
3131 from = TREE_OPERAND (*expr_p, 1);
3133 /* Mark the RHS addressable. Beware that it may not be possible to do so
3134 directly if a temporary has been created by the gimplification. */
3135 prepare_gimple_addressable (&from, seq_p);
3137 mark_addressable (from);
3138 from_ptr = build_fold_addr_expr_loc (loc, from);
3139 gimplify_arg (&from_ptr, seq_p, loc);
3141 mark_addressable (to);
3142 to_ptr = build_fold_addr_expr_loc (loc, to);
3143 gimplify_arg (&to_ptr, seq_p, loc);
3145 t = implicit_built_in_decls[BUILT_IN_MEMCPY];
3147 gs = gimple_build_call (t, 3, to_ptr, from_ptr, size);
3151 /* tmp = memcpy() */
3152 t = create_tmp_var (TREE_TYPE (to_ptr), NULL);
3153 gimple_call_set_lhs (gs, t);
3154 gimplify_seq_add_stmt (seq_p, gs);
3156 *expr_p = build1 (INDIRECT_REF, TREE_TYPE (to), t);
3160 gimplify_seq_add_stmt (seq_p, gs);
3165 /* A subroutine of gimplify_modify_expr. Replace a MODIFY_EXPR with
3166 a call to __builtin_memset. In this case we know that the RHS is
3167 a CONSTRUCTOR with an empty element list. */
3169 static enum gimplify_status
3170 gimplify_modify_expr_to_memset (tree *expr_p, tree size, bool want_value,
3173 tree t, from, to, to_ptr;
3175 location_t loc = EXPR_LOCATION (*expr_p);
3177 /* Assert our assumptions, to abort instead of producing wrong code
3178 silently if they are not met. Beware that the RHS CONSTRUCTOR might
3179 not be immediately exposed. */
3180 from = TREE_OPERAND (*expr_p, 1);
3181 if (TREE_CODE (from) == WITH_SIZE_EXPR)
3182 from = TREE_OPERAND (from, 0);
3184 gcc_assert (TREE_CODE (from) == CONSTRUCTOR
3185 && VEC_empty (constructor_elt, CONSTRUCTOR_ELTS (from)));
3188 to = TREE_OPERAND (*expr_p, 0);
3190 to_ptr = build_fold_addr_expr_loc (loc, to);
3191 gimplify_arg (&to_ptr, seq_p, loc);
3192 t = implicit_built_in_decls[BUILT_IN_MEMSET];
3194 gs = gimple_build_call (t, 3, to_ptr, integer_zero_node, size);
3198 /* tmp = memset() */
3199 t = create_tmp_var (TREE_TYPE (to_ptr), NULL);
3200 gimple_call_set_lhs (gs, t);
3201 gimplify_seq_add_stmt (seq_p, gs);
3203 *expr_p = build1 (INDIRECT_REF, TREE_TYPE (to), t);
3207 gimplify_seq_add_stmt (seq_p, gs);
3212 /* A subroutine of gimplify_init_ctor_preeval. Called via walk_tree,
3213 determine, cautiously, if a CONSTRUCTOR overlaps the lhs of an
3214 assignment. Returns non-null if we detect a potential overlap. */
3216 struct gimplify_init_ctor_preeval_data
3218 /* The base decl of the lhs object. May be NULL, in which case we
3219 have to assume the lhs is indirect. */
3222 /* The alias set of the lhs object. */
3223 alias_set_type lhs_alias_set;
3227 gimplify_init_ctor_preeval_1 (tree *tp, int *walk_subtrees, void *xdata)
3229 struct gimplify_init_ctor_preeval_data *data
3230 = (struct gimplify_init_ctor_preeval_data *) xdata;
3233 /* If we find the base object, obviously we have overlap. */
3234 if (data->lhs_base_decl == t)
3237 /* If the constructor component is indirect, determine if we have a
3238 potential overlap with the lhs. The only bits of information we
3239 have to go on at this point are addressability and alias sets. */
3240 if (TREE_CODE (t) == INDIRECT_REF
3241 && (!data->lhs_base_decl || TREE_ADDRESSABLE (data->lhs_base_decl))
3242 && alias_sets_conflict_p (data->lhs_alias_set, get_alias_set (t)))
3245 /* If the constructor component is a call, determine if it can hide a
3246 potential overlap with the lhs through an INDIRECT_REF like above. */
3247 if (TREE_CODE (t) == CALL_EXPR)
3249 tree type, fntype = TREE_TYPE (TREE_TYPE (CALL_EXPR_FN (t)));
3251 for (type = TYPE_ARG_TYPES (fntype); type; type = TREE_CHAIN (type))
3252 if (POINTER_TYPE_P (TREE_VALUE (type))
3253 && (!data->lhs_base_decl || TREE_ADDRESSABLE (data->lhs_base_decl))
3254 && alias_sets_conflict_p (data->lhs_alias_set,
3256 (TREE_TYPE (TREE_VALUE (type)))))
3260 if (IS_TYPE_OR_DECL_P (t))
3265 /* A subroutine of gimplify_init_constructor. Pre-evaluate EXPR,
3266 force values that overlap with the lhs (as described by *DATA)
3267 into temporaries. */
3270 gimplify_init_ctor_preeval (tree *expr_p, gimple_seq *pre_p, gimple_seq *post_p,
3271 struct gimplify_init_ctor_preeval_data *data)
3273 enum gimplify_status one;
3275 /* If the value is constant, then there's nothing to pre-evaluate. */
3276 if (TREE_CONSTANT (*expr_p))
3278 /* Ensure it does not have side effects, it might contain a reference to
3279 the object we're initializing. */
3280 gcc_assert (!TREE_SIDE_EFFECTS (*expr_p));
3284 /* If the type has non-trivial constructors, we can't pre-evaluate. */
3285 if (TREE_ADDRESSABLE (TREE_TYPE (*expr_p)))
3288 /* Recurse for nested constructors. */
3289 if (TREE_CODE (*expr_p) == CONSTRUCTOR)
3291 unsigned HOST_WIDE_INT ix;
3292 constructor_elt *ce;
3293 VEC(constructor_elt,gc) *v = CONSTRUCTOR_ELTS (*expr_p);
3295 for (ix = 0; VEC_iterate (constructor_elt, v, ix, ce); ix++)
3296 gimplify_init_ctor_preeval (&ce->value, pre_p, post_p, data);
3301 /* If this is a variable sized type, we must remember the size. */
3302 maybe_with_size_expr (expr_p);
3304 /* Gimplify the constructor element to something appropriate for the rhs
3305 of a MODIFY_EXPR. Given that we know the LHS is an aggregate, we know
3306 the gimplifier will consider this a store to memory. Doing this
3307 gimplification now means that we won't have to deal with complicated
3308 language-specific trees, nor trees like SAVE_EXPR that can induce
3309 exponential search behavior. */
3310 one = gimplify_expr (expr_p, pre_p, post_p, is_gimple_mem_rhs, fb_rvalue);
3311 if (one == GS_ERROR)
3317 /* If we gimplified to a bare decl, we can be sure that it doesn't overlap
3318 with the lhs, since "a = { .x=a }" doesn't make sense. This will
3319 always be true for all scalars, since is_gimple_mem_rhs insists on a
3320 temporary variable for them. */
3321 if (DECL_P (*expr_p))
3324 /* If this is of variable size, we have no choice but to assume it doesn't
3325 overlap since we can't make a temporary for it. */
3326 if (TREE_CODE (TYPE_SIZE (TREE_TYPE (*expr_p))) != INTEGER_CST)
3329 /* Otherwise, we must search for overlap ... */
3330 if (!walk_tree (expr_p, gimplify_init_ctor_preeval_1, data, NULL))
3333 /* ... and if found, force the value into a temporary. */
3334 *expr_p = get_formal_tmp_var (*expr_p, pre_p);
3337 /* A subroutine of gimplify_init_ctor_eval. Create a loop for
3338 a RANGE_EXPR in a CONSTRUCTOR for an array.
3342 object[var] = value;
3349 We increment var _after_ the loop exit check because we might otherwise
3350 fail if upper == TYPE_MAX_VALUE (type for upper).
3352 Note that we never have to deal with SAVE_EXPRs here, because this has
3353 already been taken care of for us, in gimplify_init_ctor_preeval(). */
3355 static void gimplify_init_ctor_eval (tree, VEC(constructor_elt,gc) *,
3356 gimple_seq *, bool);
3359 gimplify_init_ctor_eval_range (tree object, tree lower, tree upper,
3360 tree value, tree array_elt_type,
3361 gimple_seq *pre_p, bool cleared)
3363 tree loop_entry_label, loop_exit_label, fall_thru_label;
3364 tree var, var_type, cref, tmp;
3366 loop_entry_label = create_artificial_label (UNKNOWN_LOCATION);
3367 loop_exit_label = create_artificial_label (UNKNOWN_LOCATION);
3368 fall_thru_label = create_artificial_label (UNKNOWN_LOCATION);
3370 /* Create and initialize the index variable. */
3371 var_type = TREE_TYPE (upper);
3372 var = create_tmp_var (var_type, NULL);
3373 gimplify_seq_add_stmt (pre_p, gimple_build_assign (var, lower));
3375 /* Add the loop entry label. */
3376 gimplify_seq_add_stmt (pre_p, gimple_build_label (loop_entry_label));
3378 /* Build the reference. */
3379 cref = build4 (ARRAY_REF, array_elt_type, unshare_expr (object),
3380 var, NULL_TREE, NULL_TREE);
3382 /* If we are a constructor, just call gimplify_init_ctor_eval to do
3383 the store. Otherwise just assign value to the reference. */
3385 if (TREE_CODE (value) == CONSTRUCTOR)
3386 /* NB we might have to call ourself recursively through
3387 gimplify_init_ctor_eval if the value is a constructor. */
3388 gimplify_init_ctor_eval (cref, CONSTRUCTOR_ELTS (value),
3391 gimplify_seq_add_stmt (pre_p, gimple_build_assign (cref, value));
3393 /* We exit the loop when the index var is equal to the upper bound. */
3394 gimplify_seq_add_stmt (pre_p,
3395 gimple_build_cond (EQ_EXPR, var, upper,
3396 loop_exit_label, fall_thru_label));
3398 gimplify_seq_add_stmt (pre_p, gimple_build_label (fall_thru_label));
3400 /* Otherwise, increment the index var... */
3401 tmp = build2 (PLUS_EXPR, var_type, var,
3402 fold_convert (var_type, integer_one_node));
3403 gimplify_seq_add_stmt (pre_p, gimple_build_assign (var, tmp));
3405 /* ...and jump back to the loop entry. */
3406 gimplify_seq_add_stmt (pre_p, gimple_build_goto (loop_entry_label));
3408 /* Add the loop exit label. */
3409 gimplify_seq_add_stmt (pre_p, gimple_build_label (loop_exit_label));
3412 /* Return true if FDECL is accessing a field that is zero sized. */
3415 zero_sized_field_decl (const_tree fdecl)
3417 if (TREE_CODE (fdecl) == FIELD_DECL && DECL_SIZE (fdecl)
3418 && integer_zerop (DECL_SIZE (fdecl)))
3423 /* Return true if TYPE is zero sized. */
3426 zero_sized_type (const_tree type)
3428 if (AGGREGATE_TYPE_P (type) && TYPE_SIZE (type)
3429 && integer_zerop (TYPE_SIZE (type)))
3434 /* A subroutine of gimplify_init_constructor. Generate individual
3435 MODIFY_EXPRs for a CONSTRUCTOR. OBJECT is the LHS against which the
3436 assignments should happen. ELTS is the CONSTRUCTOR_ELTS of the
3437 CONSTRUCTOR. CLEARED is true if the entire LHS object has been
3441 gimplify_init_ctor_eval (tree object, VEC(constructor_elt,gc) *elts,
3442 gimple_seq *pre_p, bool cleared)
3444 tree array_elt_type = NULL;
3445 unsigned HOST_WIDE_INT ix;
3446 tree purpose, value;
3448 if (TREE_CODE (TREE_TYPE (object)) == ARRAY_TYPE)
3449 array_elt_type = TYPE_MAIN_VARIANT (TREE_TYPE (TREE_TYPE (object)));
3451 FOR_EACH_CONSTRUCTOR_ELT (elts, ix, purpose, value)
3455 /* NULL values are created above for gimplification errors. */
3459 if (cleared && initializer_zerop (value))
3462 /* ??? Here's to hoping the front end fills in all of the indices,
3463 so we don't have to figure out what's missing ourselves. */
3464 gcc_assert (purpose);
3466 /* Skip zero-sized fields, unless value has side-effects. This can
3467 happen with calls to functions returning a zero-sized type, which
3468 we shouldn't discard. As a number of downstream passes don't
3469 expect sets of zero-sized fields, we rely on the gimplification of
3470 the MODIFY_EXPR we make below to drop the assignment statement. */
3471 if (! TREE_SIDE_EFFECTS (value) && zero_sized_field_decl (purpose))
3474 /* If we have a RANGE_EXPR, we have to build a loop to assign the
3476 if (TREE_CODE (purpose) == RANGE_EXPR)
3478 tree lower = TREE_OPERAND (purpose, 0);
3479 tree upper = TREE_OPERAND (purpose, 1);
3481 /* If the lower bound is equal to upper, just treat it as if
3482 upper was the index. */
3483 if (simple_cst_equal (lower, upper))
3487 gimplify_init_ctor_eval_range (object, lower, upper, value,
3488 array_elt_type, pre_p, cleared);
3495 /* Do not use bitsizetype for ARRAY_REF indices. */
3496 if (TYPE_DOMAIN (TREE_TYPE (object)))
3497 purpose = fold_convert (TREE_TYPE (TYPE_DOMAIN (TREE_TYPE (object))),
3499 cref = build4 (ARRAY_REF, array_elt_type, unshare_expr (object),
3500 purpose, NULL_TREE, NULL_TREE);
3504 gcc_assert (TREE_CODE (purpose) == FIELD_DECL);
3505 cref = build3 (COMPONENT_REF, TREE_TYPE (purpose),
3506 unshare_expr (object), purpose, NULL_TREE);
3509 if (TREE_CODE (value) == CONSTRUCTOR
3510 && TREE_CODE (TREE_TYPE (value)) != VECTOR_TYPE)
3511 gimplify_init_ctor_eval (cref, CONSTRUCTOR_ELTS (value),
3515 tree init = build2 (INIT_EXPR, TREE_TYPE (cref), cref, value);
3516 gimplify_and_add (init, pre_p);
3523 /* Returns the appropriate RHS predicate for this LHS. */
3526 rhs_predicate_for (tree lhs)
3528 if (is_gimple_reg (lhs))
3529 return is_gimple_reg_rhs_or_call;
3531 return is_gimple_mem_rhs_or_call;
3534 /* Gimplify a C99 compound literal expression. This just means adding
3535 the DECL_EXPR before the current statement and using its anonymous
3538 static enum gimplify_status
3539 gimplify_compound_literal_expr (tree *expr_p, gimple_seq *pre_p)
3541 tree decl_s = COMPOUND_LITERAL_EXPR_DECL_EXPR (*expr_p);
3542 tree decl = DECL_EXPR_DECL (decl_s);
3543 /* Mark the decl as addressable if the compound literal
3544 expression is addressable now, otherwise it is marked too late
3545 after we gimplify the initialization expression. */
3546 if (TREE_ADDRESSABLE (*expr_p))
3547 TREE_ADDRESSABLE (decl) = 1;
3549 /* Preliminarily mark non-addressed complex variables as eligible
3550 for promotion to gimple registers. We'll transform their uses
3552 if ((TREE_CODE (TREE_TYPE (decl)) == COMPLEX_TYPE
3553 || TREE_CODE (TREE_TYPE (decl)) == VECTOR_TYPE)
3554 && !TREE_THIS_VOLATILE (decl)
3555 && !needs_to_live_in_memory (decl))
3556 DECL_GIMPLE_REG_P (decl) = 1;
3558 /* This decl isn't mentioned in the enclosing block, so add it to the
3559 list of temps. FIXME it seems a bit of a kludge to say that
3560 anonymous artificial vars aren't pushed, but everything else is. */
3561 if (DECL_NAME (decl) == NULL_TREE && !DECL_SEEN_IN_BIND_EXPR_P (decl))
3562 gimple_add_tmp_var (decl);
3564 gimplify_and_add (decl_s, pre_p);
3569 /* Optimize embedded COMPOUND_LITERAL_EXPRs within a CONSTRUCTOR,
3570 return a new CONSTRUCTOR if something changed. */
3573 optimize_compound_literals_in_ctor (tree orig_ctor)
3575 tree ctor = orig_ctor;
3576 VEC(constructor_elt,gc) *elts = CONSTRUCTOR_ELTS (ctor);
3577 unsigned int idx, num = VEC_length (constructor_elt, elts);
3579 for (idx = 0; idx < num; idx++)
3581 tree value = VEC_index (constructor_elt, elts, idx)->value;
3582 tree newval = value;
3583 if (TREE_CODE (value) == CONSTRUCTOR)
3584 newval = optimize_compound_literals_in_ctor (value);
3585 else if (TREE_CODE (value) == COMPOUND_LITERAL_EXPR)
3587 tree decl_s = COMPOUND_LITERAL_EXPR_DECL_EXPR (value);
3588 tree decl = DECL_EXPR_DECL (decl_s);
3589 tree init = DECL_INITIAL (decl);
3591 if (!TREE_ADDRESSABLE (value)
3592 && !TREE_ADDRESSABLE (decl)
3594 newval = optimize_compound_literals_in_ctor (init);
3596 if (newval == value)
3599 if (ctor == orig_ctor)
3601 ctor = copy_node (orig_ctor);
3602 CONSTRUCTOR_ELTS (ctor) = VEC_copy (constructor_elt, gc, elts);
3603 elts = CONSTRUCTOR_ELTS (ctor);
3605 VEC_index (constructor_elt, elts, idx)->value = newval;
3612 /* A subroutine of gimplify_modify_expr. Break out elements of a
3613 CONSTRUCTOR used as an initializer into separate MODIFY_EXPRs.
3615 Note that we still need to clear any elements that don't have explicit
3616 initializers, so if not all elements are initialized we keep the
3617 original MODIFY_EXPR, we just remove all of the constructor elements.
3619 If NOTIFY_TEMP_CREATION is true, do not gimplify, just return
3620 GS_ERROR if we would have to create a temporary when gimplifying
3621 this constructor. Otherwise, return GS_OK.
3623 If NOTIFY_TEMP_CREATION is false, just do the gimplification. */
3625 static enum gimplify_status
3626 gimplify_init_constructor (tree *expr_p, gimple_seq *pre_p, gimple_seq *post_p,
3627 bool want_value, bool notify_temp_creation)
3629 tree object, ctor, type;
3630 enum gimplify_status ret;
3631 VEC(constructor_elt,gc) *elts;
3633 gcc_assert (TREE_CODE (TREE_OPERAND (*expr_p, 1)) == CONSTRUCTOR);
3635 if (!notify_temp_creation)
3637 ret = gimplify_expr (&TREE_OPERAND (*expr_p, 0), pre_p, post_p,
3638 is_gimple_lvalue, fb_lvalue);
3639 if (ret == GS_ERROR)
3643 object = TREE_OPERAND (*expr_p, 0);
3644 ctor = TREE_OPERAND (*expr_p, 1) =
3645 optimize_compound_literals_in_ctor (TREE_OPERAND (*expr_p, 1));
3646 type = TREE_TYPE (ctor);
3647 elts = CONSTRUCTOR_ELTS (ctor);
3650 switch (TREE_CODE (type))
3654 case QUAL_UNION_TYPE:
3657 struct gimplify_init_ctor_preeval_data preeval_data;
3658 HOST_WIDE_INT num_type_elements, num_ctor_elements;
3659 HOST_WIDE_INT num_nonzero_elements;
3660 bool cleared, valid_const_initializer;
3662 /* Aggregate types must lower constructors to initialization of
3663 individual elements. The exception is that a CONSTRUCTOR node
3664 with no elements indicates zero-initialization of the whole. */
3665 if (VEC_empty (constructor_elt, elts))
3667 if (notify_temp_creation)
3672 /* Fetch information about the constructor to direct later processing.
3673 We might want to make static versions of it in various cases, and
3674 can only do so if it known to be a valid constant initializer. */
3675 valid_const_initializer
3676 = categorize_ctor_elements (ctor, &num_nonzero_elements,
3677 &num_ctor_elements, &cleared);
3679 /* If a const aggregate variable is being initialized, then it
3680 should never be a lose to promote the variable to be static. */
3681 if (valid_const_initializer
3682 && num_nonzero_elements > 1
3683 && TREE_READONLY (object)
3684 && TREE_CODE (object) == VAR_DECL
3685 && (flag_merge_constants >= 2 || !TREE_ADDRESSABLE (object)))
3687 if (notify_temp_creation)
3689 DECL_INITIAL (object) = ctor;
3690 TREE_STATIC (object) = 1;
3691 if (!DECL_NAME (object))
3692 DECL_NAME (object) = create_tmp_var_name ("C");
3693 walk_tree (&DECL_INITIAL (object), force_labels_r, NULL, NULL);
3695 /* ??? C++ doesn't automatically append a .<number> to the
3696 assembler name, and even when it does, it looks a FE private
3697 data structures to figure out what that number should be,
3698 which are not set for this variable. I suppose this is
3699 important for local statics for inline functions, which aren't
3700 "local" in the object file sense. So in order to get a unique
3701 TU-local symbol, we must invoke the lhd version now. */
3702 lhd_set_decl_assembler_name (object);
3704 *expr_p = NULL_TREE;
3708 /* If there are "lots" of initialized elements, even discounting
3709 those that are not address constants (and thus *must* be
3710 computed at runtime), then partition the constructor into
3711 constant and non-constant parts. Block copy the constant
3712 parts in, then generate code for the non-constant parts. */
3713 /* TODO. There's code in cp/typeck.c to do this. */
3715 num_type_elements = count_type_elements (type, true);
3717 /* If count_type_elements could not determine number of type elements
3718 for a constant-sized object, assume clearing is needed.
3719 Don't do this for variable-sized objects, as store_constructor
3720 will ignore the clearing of variable-sized objects. */
3721 if (num_type_elements < 0 && int_size_in_bytes (type) >= 0)
3723 /* If there are "lots" of zeros, then block clear the object first. */
3724 else if (num_type_elements - num_nonzero_elements
3725 > CLEAR_RATIO (optimize_function_for_speed_p (cfun))
3726 && num_nonzero_elements < num_type_elements/4)
3728 /* ??? This bit ought not be needed. For any element not present
3729 in the initializer, we should simply set them to zero. Except
3730 we'd need to *find* the elements that are not present, and that
3731 requires trickery to avoid quadratic compile-time behavior in
3732 large cases or excessive memory use in small cases. */
3733 else if (num_ctor_elements < num_type_elements)
3736 /* If there are "lots" of initialized elements, and all of them
3737 are valid address constants, then the entire initializer can
3738 be dropped to memory, and then memcpy'd out. Don't do this
3739 for sparse arrays, though, as it's more efficient to follow
3740 the standard CONSTRUCTOR behavior of memset followed by
3741 individual element initialization. Also don't do this for small
3742 all-zero initializers (which aren't big enough to merit
3743 clearing), and don't try to make bitwise copies of
3744 TREE_ADDRESSABLE types. */
3745 if (valid_const_initializer
3746 && !(cleared || num_nonzero_elements == 0)
3747 && !TREE_ADDRESSABLE (type))
3749 HOST_WIDE_INT size = int_size_in_bytes (type);
3752 /* ??? We can still get unbounded array types, at least
3753 from the C++ front end. This seems wrong, but attempt
3754 to work around it for now. */
3757 size = int_size_in_bytes (TREE_TYPE (object));
3759 TREE_TYPE (ctor) = type = TREE_TYPE (object);
3762 /* Find the maximum alignment we can assume for the object. */
3763 /* ??? Make use of DECL_OFFSET_ALIGN. */
3764 if (DECL_P (object))
3765 align = DECL_ALIGN (object);
3767 align = TYPE_ALIGN (type);
3770 && num_nonzero_elements > 1
3771 && !can_move_by_pieces (size, align))
3773 if (notify_temp_creation)
3776 walk_tree (&ctor, force_labels_r, NULL, NULL);
3777 TREE_OPERAND (*expr_p, 1) = tree_output_constant_def (ctor);
3779 /* This is no longer an assignment of a CONSTRUCTOR, but
3780 we still may have processing to do on the LHS. So
3781 pretend we didn't do anything here to let that happen. */
3782 return GS_UNHANDLED;
3786 /* If the target is volatile and we have non-zero elements
3787 initialize the target from a temporary. */
3788 if (TREE_THIS_VOLATILE (object)
3789 && !TREE_ADDRESSABLE (type)
3790 && num_nonzero_elements > 0)
3792 tree temp = create_tmp_var (TYPE_MAIN_VARIANT (type), NULL);
3793 TREE_OPERAND (*expr_p, 0) = temp;
3794 *expr_p = build2 (COMPOUND_EXPR, TREE_TYPE (*expr_p),
3796 build2 (MODIFY_EXPR, void_type_node,
3801 if (notify_temp_creation)
3804 /* If there are nonzero elements and if needed, pre-evaluate to capture
3805 elements overlapping with the lhs into temporaries. We must do this
3806 before clearing to fetch the values before they are zeroed-out. */
3807 if (num_nonzero_elements > 0 && TREE_CODE (*expr_p) != INIT_EXPR)
3809 preeval_data.lhs_base_decl = get_base_address (object);
3810 if (!DECL_P (preeval_data.lhs_base_decl))
3811 preeval_data.lhs_base_decl = NULL;
3812 preeval_data.lhs_alias_set = get_alias_set (object);
3814 gimplify_init_ctor_preeval (&TREE_OPERAND (*expr_p, 1),
3815 pre_p, post_p, &preeval_data);
3820 /* Zap the CONSTRUCTOR element list, which simplifies this case.
3821 Note that we still have to gimplify, in order to handle the
3822 case of variable sized types. Avoid shared tree structures. */
3823 CONSTRUCTOR_ELTS (ctor) = NULL;
3824 TREE_SIDE_EFFECTS (ctor) = 0;
3825 object = unshare_expr (object);
3826 gimplify_stmt (expr_p, pre_p);
3829 /* If we have not block cleared the object, or if there are nonzero
3830 elements in the constructor, add assignments to the individual
3831 scalar fields of the object. */
3832 if (!cleared || num_nonzero_elements > 0)
3833 gimplify_init_ctor_eval (object, elts, pre_p, cleared);
3835 *expr_p = NULL_TREE;
3843 if (notify_temp_creation)
3846 /* Extract the real and imaginary parts out of the ctor. */
3847 gcc_assert (VEC_length (constructor_elt, elts) == 2);
3848 r = VEC_index (constructor_elt, elts, 0)->value;
3849 i = VEC_index (constructor_elt, elts, 1)->value;
3850 if (r == NULL || i == NULL)
3852 tree zero = fold_convert (TREE_TYPE (type), integer_zero_node);
3859 /* Complex types have either COMPLEX_CST or COMPLEX_EXPR to
3860 represent creation of a complex value. */
3861 if (TREE_CONSTANT (r) && TREE_CONSTANT (i))
3863 ctor = build_complex (type, r, i);
3864 TREE_OPERAND (*expr_p, 1) = ctor;
3868 ctor = build2 (COMPLEX_EXPR, type, r, i);
3869 TREE_OPERAND (*expr_p, 1) = ctor;
3870 ret = gimplify_expr (&TREE_OPERAND (*expr_p, 1),
3873 rhs_predicate_for (TREE_OPERAND (*expr_p, 0)),
3881 unsigned HOST_WIDE_INT ix;
3882 constructor_elt *ce;
3884 if (notify_temp_creation)
3887 /* Go ahead and simplify constant constructors to VECTOR_CST. */
3888 if (TREE_CONSTANT (ctor))
3890 bool constant_p = true;
3893 /* Even when ctor is constant, it might contain non-*_CST
3894 elements, such as addresses or trapping values like
3895 1.0/0.0 - 1.0/0.0. Such expressions don't belong
3896 in VECTOR_CST nodes. */
3897 FOR_EACH_CONSTRUCTOR_VALUE (elts, ix, value)
3898 if (!CONSTANT_CLASS_P (value))
3906 TREE_OPERAND (*expr_p, 1) = build_vector_from_ctor (type, elts);
3910 /* Don't reduce an initializer constant even if we can't
3911 make a VECTOR_CST. It won't do anything for us, and it'll
3912 prevent us from representing it as a single constant. */
3913 if (initializer_constant_valid_p (ctor, type))
3916 TREE_CONSTANT (ctor) = 0;
3919 /* Vector types use CONSTRUCTOR all the way through gimple
3920 compilation as a general initializer. */
3921 for (ix = 0; VEC_iterate (constructor_elt, elts, ix, ce); ix++)
3923 enum gimplify_status tret;
3924 tret = gimplify_expr (&ce->value, pre_p, post_p, is_gimple_val,
3926 if (tret == GS_ERROR)
3929 if (!is_gimple_reg (TREE_OPERAND (*expr_p, 0)))
3930 TREE_OPERAND (*expr_p, 1) = get_formal_tmp_var (ctor, pre_p);
3935 /* So how did we get a CONSTRUCTOR for a scalar type? */
3939 if (ret == GS_ERROR)
3941 else if (want_value)
3948 /* If we have gimplified both sides of the initializer but have
3949 not emitted an assignment, do so now. */
3952 tree lhs = TREE_OPERAND (*expr_p, 0);
3953 tree rhs = TREE_OPERAND (*expr_p, 1);
3954 gimple init = gimple_build_assign (lhs, rhs);
3955 gimplify_seq_add_stmt (pre_p, init);
3963 /* Given a pointer value OP0, return a simplified version of an
3964 indirection through OP0, or NULL_TREE if no simplification is
3965 possible. Note that the resulting type may be different from
3966 the type pointed to in the sense that it is still compatible
3967 from the langhooks point of view. */
3970 gimple_fold_indirect_ref (tree t)
3972 tree type = TREE_TYPE (TREE_TYPE (t));
3977 subtype = TREE_TYPE (sub);
3978 if (!POINTER_TYPE_P (subtype))
3981 if (TREE_CODE (sub) == ADDR_EXPR)
3983 tree op = TREE_OPERAND (sub, 0);
3984 tree optype = TREE_TYPE (op);
3986 if (useless_type_conversion_p (type, optype))
3989 /* *(foo *)&fooarray => fooarray[0] */
3990 if (TREE_CODE (optype) == ARRAY_TYPE
3991 && TREE_CODE (TYPE_SIZE (TREE_TYPE (optype))) == INTEGER_CST
3992 && useless_type_conversion_p (type, TREE_TYPE (optype)))
3994 tree type_domain = TYPE_DOMAIN (optype);
3995 tree min_val = size_zero_node;
3996 if (type_domain && TYPE_MIN_VALUE (type_domain))
3997 min_val = TYPE_MIN_VALUE (type_domain);
3998 if (TREE_CODE (min_val) == INTEGER_CST)
3999 return build4 (ARRAY_REF, type, op, min_val, NULL_TREE, NULL_TREE);
4001 /* *(foo *)&complexfoo => __real__ complexfoo */
4002 else if (TREE_CODE (optype) == COMPLEX_TYPE
4003 && useless_type_conversion_p (type, TREE_TYPE (optype)))
4004 return fold_build1 (REALPART_EXPR, type, op);
4005 /* *(foo *)&vectorfoo => BIT_FIELD_REF<vectorfoo,...> */
4006 else if (TREE_CODE (optype) == VECTOR_TYPE
4007 && useless_type_conversion_p (type, TREE_TYPE (optype)))
4009 tree part_width = TYPE_SIZE (type);
4010 tree index = bitsize_int (0);
4011 return fold_build3 (BIT_FIELD_REF, type, op, part_width, index);
4015 /* ((foo*)&vectorfoo)[1] => BIT_FIELD_REF<vectorfoo,...> */
4016 if (TREE_CODE (sub) == POINTER_PLUS_EXPR
4017 && TREE_CODE (TREE_OPERAND (sub, 1)) == INTEGER_CST)
4019 tree op00 = TREE_OPERAND (sub, 0);
4020 tree op01 = TREE_OPERAND (sub, 1);
4024 op00type = TREE_TYPE (op00);
4025 if (TREE_CODE (op00) == ADDR_EXPR
4026 && TREE_CODE (TREE_TYPE (op00type)) == VECTOR_TYPE
4027 && useless_type_conversion_p (type, TREE_TYPE (TREE_TYPE (op00type))))
4029 HOST_WIDE_INT offset = tree_low_cst (op01, 0);
4030 tree part_width = TYPE_SIZE (type);
4031 unsigned HOST_WIDE_INT part_widthi
4032 = tree_low_cst (part_width, 0) / BITS_PER_UNIT;
4033 unsigned HOST_WIDE_INT indexi = offset * BITS_PER_UNIT;
4034 tree index = bitsize_int (indexi);
4035 if (offset / part_widthi
4036 <= TYPE_VECTOR_SUBPARTS (TREE_TYPE (op00type)))
4037 return fold_build3 (BIT_FIELD_REF, type, TREE_OPERAND (op00, 0),
4042 /* ((foo*)&complexfoo)[1] => __imag__ complexfoo */
4043 if (TREE_CODE (sub) == POINTER_PLUS_EXPR
4044 && TREE_CODE (TREE_OPERAND (sub, 1)) == INTEGER_CST)
4046 tree op00 = TREE_OPERAND (sub, 0);
4047 tree op01 = TREE_OPERAND (sub, 1);
4051 op00type = TREE_TYPE (op00);
4052 if (TREE_CODE (op00) == ADDR_EXPR
4053 && TREE_CODE (TREE_TYPE (op00type)) == COMPLEX_TYPE
4054 && useless_type_conversion_p (type, TREE_TYPE (TREE_TYPE (op00type))))
4056 tree size = TYPE_SIZE_UNIT (type);
4057 if (tree_int_cst_equal (size, op01))
4058 return fold_build1 (IMAGPART_EXPR, type, TREE_OPERAND (op00, 0));
4062 /* *(foo *)fooarrptr => (*fooarrptr)[0] */
4063 if (TREE_CODE (TREE_TYPE (subtype)) == ARRAY_TYPE
4064 && TREE_CODE (TYPE_SIZE (TREE_TYPE (TREE_TYPE (subtype)))) == INTEGER_CST
4065 && useless_type_conversion_p (type, TREE_TYPE (TREE_TYPE (subtype))))
4068 tree min_val = size_zero_node;
4070 sub = gimple_fold_indirect_ref (sub);
4072 sub = build1 (INDIRECT_REF, TREE_TYPE (subtype), osub);
4073 type_domain = TYPE_DOMAIN (TREE_TYPE (sub));
4074 if (type_domain && TYPE_MIN_VALUE (type_domain))
4075 min_val = TYPE_MIN_VALUE (type_domain);
4076 if (TREE_CODE (min_val) == INTEGER_CST)
4077 return build4 (ARRAY_REF, type, sub, min_val, NULL_TREE, NULL_TREE);
4083 /* Given a pointer value OP0, return a simplified version of an
4084 indirection through OP0, or NULL_TREE if no simplification is
4085 possible. This may only be applied to a rhs of an expression.
4086 Note that the resulting type may be different from the type pointed
4087 to in the sense that it is still compatible from the langhooks
4091 gimple_fold_indirect_ref_rhs (tree t)
4093 return gimple_fold_indirect_ref (t);
4096 /* Subroutine of gimplify_modify_expr to do simplifications of
4097 MODIFY_EXPRs based on the code of the RHS. We loop for as long as
4098 something changes. */
4100 static enum gimplify_status
4101 gimplify_modify_expr_rhs (tree *expr_p, tree *from_p, tree *to_p,
4102 gimple_seq *pre_p, gimple_seq *post_p,
4105 enum gimplify_status ret = GS_UNHANDLED;
4111 switch (TREE_CODE (*from_p))
4114 /* If we're assigning from a read-only variable initialized with
4115 a constructor, do the direct assignment from the constructor,
4116 but only if neither source nor target are volatile since this
4117 latter assignment might end up being done on a per-field basis. */
4118 if (DECL_INITIAL (*from_p)
4119 && TREE_READONLY (*from_p)
4120 && !TREE_THIS_VOLATILE (*from_p)
4121 && !TREE_THIS_VOLATILE (*to_p)
4122 && TREE_CODE (DECL_INITIAL (*from_p)) == CONSTRUCTOR)
4124 tree old_from = *from_p;
4125 enum gimplify_status subret;
4127 /* Move the constructor into the RHS. */
4128 *from_p = unshare_expr (DECL_INITIAL (*from_p));
4130 /* Let's see if gimplify_init_constructor will need to put
4132 subret = gimplify_init_constructor (expr_p, NULL, NULL,
4134 if (subret == GS_ERROR)
4136 /* If so, revert the change. */
4148 /* If we have code like
4152 where the type of "x" is a (possibly cv-qualified variant
4153 of "A"), treat the entire expression as identical to "x".
4154 This kind of code arises in C++ when an object is bound
4155 to a const reference, and if "x" is a TARGET_EXPR we want
4156 to take advantage of the optimization below. */
4157 tree t = gimple_fold_indirect_ref_rhs (TREE_OPERAND (*from_p, 0));
4169 /* If we are initializing something from a TARGET_EXPR, strip the
4170 TARGET_EXPR and initialize it directly, if possible. This can't
4171 be done if the initializer is void, since that implies that the
4172 temporary is set in some non-trivial way.
4174 ??? What about code that pulls out the temp and uses it
4175 elsewhere? I think that such code never uses the TARGET_EXPR as
4176 an initializer. If I'm wrong, we'll die because the temp won't
4177 have any RTL. In that case, I guess we'll need to replace
4178 references somehow. */