1 /* Alias analysis for trees.
2 Copyright (C) 2004, 2005, 2006, 2007, 2008, 2009
3 Free Software Foundation, Inc.
4 Contributed by Diego Novillo <dnovillo@redhat.com>
6 This file is part of GCC.
8 GCC is free software; you can redistribute it and/or modify
9 it under the terms of the GNU General Public License as published by
10 the Free Software Foundation; either version 3, or (at your option)
13 GCC is distributed in the hope that it will be useful,
14 but WITHOUT ANY WARRANTY; without even the implied warranty of
15 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16 GNU General Public License for more details.
18 You should have received a copy of the GNU General Public License
19 along with GCC; see the file COPYING3. If not see
20 <http://www.gnu.org/licenses/>. */
24 #include "coretypes.h"
29 #include "hard-reg-set.h"
30 #include "basic-block.h"
34 #include "langhooks.h"
37 #include "diagnostic.h"
38 #include "tree-dump.h"
40 #include "tree-flow.h"
41 #include "tree-inline.h"
42 #include "tree-pass.h"
45 #include "ipa-type-escape.h"
49 #include "pointer-set.h"
50 #include "alloc-pool.h"
51 #include "tree-ssa-alias.h"
53 /* Broad overview of how alias analysis on gimple works:
55 Statements clobbering or using memory are linked through the
56 virtual operand factored use-def chain. The virtual operand
57 is unique per function, its symbol is accessible via gimple_vop (cfun).
58 Virtual operands are used for efficiently walking memory statements
59 in the gimple IL and are useful for things like value-numbering as
60 a generation count for memory references.
62 SSA_NAME pointers may have associated points-to information
63 accessible via the SSA_NAME_PTR_INFO macro. Flow-insensitive
64 points-to information is (re-)computed by the TODO_rebuild_alias
65 pass manager todo. Points-to information is also used for more
66 precise tracking of call-clobbered and call-used variables and
67 related disambiguations.
69 This file contains functions for disambiguating memory references,
70 the so called alias-oracle and tools for walking of the gimple IL.
72 The main alias-oracle entry-points are
74 bool stmt_may_clobber_ref_p (gimple, tree)
76 This function queries if a statement may invalidate (parts of)
77 the memory designated by the reference tree argument.
79 bool ref_maybe_used_by_stmt_p (gimple, tree)
81 This function queries if a statement may need (parts of) the
82 memory designated by the reference tree argument.
84 There are variants of these functions that only handle the call
85 part of a statement, call_may_clobber_ref_p and ref_maybe_used_by_call_p.
86 Note that these do not disambiguate against a possible call lhs.
88 bool refs_may_alias_p (tree, tree)
90 This function tries to disambiguate two reference trees.
92 bool ptr_deref_may_alias_global_p (tree)
94 This function queries if dereferencing a pointer variable may
97 More low-level disambiguators are available and documented in
98 this file. Low-level disambiguators dealing with points-to
99 information are in tree-ssa-structalias.c. */
102 /* Query statistics for the different low-level disambiguators.
103 A high-level query may trigger multiple of them. */
106 unsigned HOST_WIDE_INT refs_may_alias_p_may_alias
;
107 unsigned HOST_WIDE_INT refs_may_alias_p_no_alias
;
108 unsigned HOST_WIDE_INT ref_maybe_used_by_call_p_may_alias
;
109 unsigned HOST_WIDE_INT ref_maybe_used_by_call_p_no_alias
;
110 unsigned HOST_WIDE_INT call_may_clobber_ref_p_may_alias
;
111 unsigned HOST_WIDE_INT call_may_clobber_ref_p_no_alias
;
115 dump_alias_stats (FILE *s
)
117 fprintf (s
, "\nAlias oracle query stats:\n");
118 fprintf (s
, " refs_may_alias_p: "
119 HOST_WIDE_INT_PRINT_DEC
" disambiguations, "
120 HOST_WIDE_INT_PRINT_DEC
" queries\n",
121 alias_stats
.refs_may_alias_p_no_alias
,
122 alias_stats
.refs_may_alias_p_no_alias
123 + alias_stats
.refs_may_alias_p_may_alias
);
124 fprintf (s
, " ref_maybe_used_by_call_p: "
125 HOST_WIDE_INT_PRINT_DEC
" disambiguations, "
126 HOST_WIDE_INT_PRINT_DEC
" queries\n",
127 alias_stats
.ref_maybe_used_by_call_p_no_alias
,
128 alias_stats
.refs_may_alias_p_no_alias
129 + alias_stats
.ref_maybe_used_by_call_p_may_alias
);
130 fprintf (s
, " call_may_clobber_ref_p: "
131 HOST_WIDE_INT_PRINT_DEC
" disambiguations, "
132 HOST_WIDE_INT_PRINT_DEC
" queries\n",
133 alias_stats
.call_may_clobber_ref_p_no_alias
,
134 alias_stats
.call_may_clobber_ref_p_no_alias
135 + alias_stats
.call_may_clobber_ref_p_may_alias
);
139 /* Return true, if dereferencing PTR may alias with a global variable. */
142 ptr_deref_may_alias_global_p (tree ptr
)
144 struct ptr_info_def
*pi
;
146 /* If we end up with a pointer constant here that may point
148 if (TREE_CODE (ptr
) != SSA_NAME
)
151 pi
= SSA_NAME_PTR_INFO (ptr
);
153 /* If we do not have points-to information for this variable,
158 /* ??? This does not use TBAA to prune globals ptr may not access. */
159 return pt_solution_includes_global (&pi
->pt
);
162 /* Return true if dereferencing PTR may alias DECL.
163 The caller is responsible for applying TBAA to see if PTR
164 may access DECL at all. */
167 ptr_deref_may_alias_decl_p (tree ptr
, tree decl
)
169 struct ptr_info_def
*pi
;
171 gcc_assert ((TREE_CODE (ptr
) == SSA_NAME
172 || TREE_CODE (ptr
) == ADDR_EXPR
173 || TREE_CODE (ptr
) == INTEGER_CST
)
174 && (TREE_CODE (decl
) == VAR_DECL
175 || TREE_CODE (decl
) == PARM_DECL
176 || TREE_CODE (decl
) == RESULT_DECL
));
178 /* Non-aliased variables can not be pointed to. */
179 if (!may_be_aliased (decl
))
182 /* ADDR_EXPR pointers either just offset another pointer or directly
183 specify the pointed-to set. */
184 if (TREE_CODE (ptr
) == ADDR_EXPR
)
186 tree base
= get_base_address (TREE_OPERAND (ptr
, 0));
188 && INDIRECT_REF_P (base
))
189 ptr
= TREE_OPERAND (base
, 0);
192 return operand_equal_p (base
, decl
, 0);
194 && CONSTANT_CLASS_P (base
))
200 /* We can end up with dereferencing constant pointers.
201 Just bail out in this case. */
202 if (TREE_CODE (ptr
) == INTEGER_CST
)
205 /* If we do not have useful points-to information for this pointer
206 we cannot disambiguate anything else. */
207 pi
= SSA_NAME_PTR_INFO (ptr
);
211 /* If the decl can be used as a restrict tag and we have a restrict
212 pointer and that pointers points-to set doesn't contain this decl
213 then they can't alias. */
214 if (DECL_RESTRICTED_P (decl
)
215 && TYPE_RESTRICT (TREE_TYPE (ptr
))
216 && pi
->pt
.vars_contains_restrict
)
217 return bitmap_bit_p (pi
->pt
.vars
, DECL_UID (decl
));
219 return pt_solution_includes (&pi
->pt
, decl
);
222 /* Return true if dereferenced PTR1 and PTR2 may alias.
223 The caller is responsible for applying TBAA to see if accesses
224 through PTR1 and PTR2 may conflict at all. */
227 ptr_derefs_may_alias_p (tree ptr1
, tree ptr2
)
229 struct ptr_info_def
*pi1
, *pi2
;
231 gcc_assert ((TREE_CODE (ptr1
) == SSA_NAME
232 || TREE_CODE (ptr1
) == ADDR_EXPR
233 || TREE_CODE (ptr1
) == INTEGER_CST
)
234 && (TREE_CODE (ptr2
) == SSA_NAME
235 || TREE_CODE (ptr2
) == ADDR_EXPR
236 || TREE_CODE (ptr2
) == INTEGER_CST
));
238 /* ADDR_EXPR pointers either just offset another pointer or directly
239 specify the pointed-to set. */
240 if (TREE_CODE (ptr1
) == ADDR_EXPR
)
242 tree base
= get_base_address (TREE_OPERAND (ptr1
, 0));
244 && INDIRECT_REF_P (base
))
245 ptr1
= TREE_OPERAND (base
, 0);
248 return ptr_deref_may_alias_decl_p (ptr2
, base
);
252 if (TREE_CODE (ptr2
) == ADDR_EXPR
)
254 tree base
= get_base_address (TREE_OPERAND (ptr2
, 0));
256 && INDIRECT_REF_P (base
))
257 ptr2
= TREE_OPERAND (base
, 0);
260 return ptr_deref_may_alias_decl_p (ptr1
, base
);
265 /* We can end up with dereferencing constant pointers.
266 Just bail out in this case. */
267 if (TREE_CODE (ptr1
) == INTEGER_CST
268 || TREE_CODE (ptr2
) == INTEGER_CST
)
271 /* We may end up with two empty points-to solutions for two same pointers.
272 In this case we still want to say both pointers alias, so shortcut
277 /* If we do not have useful points-to information for either pointer
278 we cannot disambiguate anything else. */
279 pi1
= SSA_NAME_PTR_INFO (ptr1
);
280 pi2
= SSA_NAME_PTR_INFO (ptr2
);
284 /* If both pointers are restrict-qualified try to disambiguate
285 with restrict information. */
286 if (TYPE_RESTRICT (TREE_TYPE (ptr1
))
287 && TYPE_RESTRICT (TREE_TYPE (ptr2
))
288 && !pt_solutions_same_restrict_base (&pi1
->pt
, &pi2
->pt
))
291 /* ??? This does not use TBAA to prune decls from the intersection
292 that not both pointers may access. */
293 return pt_solutions_intersect (&pi1
->pt
, &pi2
->pt
);
296 /* Return true if dereferencing PTR may alias *REF.
297 The caller is responsible for applying TBAA to see if PTR
298 may access *REF at all. */
301 ptr_deref_may_alias_ref_p_1 (tree ptr
, ao_ref
*ref
)
303 tree base
= ao_ref_base (ref
);
305 if (INDIRECT_REF_P (base
))
306 return ptr_derefs_may_alias_p (ptr
, TREE_OPERAND (base
, 0));
307 else if (SSA_VAR_P (base
))
308 return ptr_deref_may_alias_decl_p (ptr
, base
);
314 /* Dump alias information on FILE. */
317 dump_alias_info (FILE *file
)
321 = lang_hooks
.decl_printable_name (current_function_decl
, 2);
322 referenced_var_iterator rvi
;
325 fprintf (file
, "\n\nAlias information for %s\n\n", funcname
);
327 fprintf (file
, "Aliased symbols\n\n");
329 FOR_EACH_REFERENCED_VAR (var
, rvi
)
331 if (may_be_aliased (var
))
332 dump_variable (file
, var
);
335 fprintf (file
, "\nCall clobber information\n");
337 fprintf (file
, "\nESCAPED");
338 dump_points_to_solution (file
, &cfun
->gimple_df
->escaped
);
339 fprintf (file
, "\nCALLUSED");
340 dump_points_to_solution (file
, &cfun
->gimple_df
->callused
);
342 fprintf (file
, "\n\nFlow-insensitive points-to information\n\n");
344 for (i
= 1; i
< num_ssa_names
; i
++)
346 tree ptr
= ssa_name (i
);
347 struct ptr_info_def
*pi
;
350 || SSA_NAME_IN_FREE_LIST (ptr
))
353 pi
= SSA_NAME_PTR_INFO (ptr
);
355 dump_points_to_info_for (file
, ptr
);
358 fprintf (file
, "\n");
362 /* Dump alias information on stderr. */
365 debug_alias_info (void)
367 dump_alias_info (stderr
);
371 /* Return the alias information associated with pointer T. It creates a
372 new instance if none existed. */
374 struct ptr_info_def
*
375 get_ptr_info (tree t
)
377 struct ptr_info_def
*pi
;
379 gcc_assert (POINTER_TYPE_P (TREE_TYPE (t
)));
381 pi
= SSA_NAME_PTR_INFO (t
);
384 pi
= GGC_CNEW (struct ptr_info_def
);
385 pt_solution_reset (&pi
->pt
);
386 SSA_NAME_PTR_INFO (t
) = pi
;
392 /* Dump the points-to set *PT into FILE. */
395 dump_points_to_solution (FILE *file
, struct pt_solution
*pt
)
398 fprintf (file
, ", points-to anything");
401 fprintf (file
, ", points-to non-local");
404 fprintf (file
, ", points-to escaped");
407 fprintf (file
, ", points-to NULL");
411 fprintf (file
, ", points-to vars: ");
412 dump_decl_set (file
, pt
->vars
);
413 if (pt
->vars_contains_global
)
414 fprintf (file
, " (includes global vars)");
418 /* Dump points-to information for SSA_NAME PTR into FILE. */
421 dump_points_to_info_for (FILE *file
, tree ptr
)
423 struct ptr_info_def
*pi
= SSA_NAME_PTR_INFO (ptr
);
425 print_generic_expr (file
, ptr
, dump_flags
);
428 dump_points_to_solution (file
, &pi
->pt
);
430 fprintf (file
, ", points-to anything");
432 fprintf (file
, "\n");
436 /* Dump points-to information for VAR into stderr. */
439 debug_points_to_info_for (tree var
)
441 dump_points_to_info_for (stderr
, var
);
445 /* Initializes the alias-oracle reference representation *R from REF. */
448 ao_ref_init (ao_ref
*r
, tree ref
)
455 r
->ref_alias_set
= -1;
456 r
->base_alias_set
= -1;
459 /* Returns the base object of the memory reference *REF. */
462 ao_ref_base (ao_ref
*ref
)
466 ref
->base
= get_ref_base_and_extent (ref
->ref
, &ref
->offset
, &ref
->size
,
471 /* Returns the base object alias set of the memory reference *REF. */
473 static alias_set_type ATTRIBUTE_UNUSED
474 ao_ref_base_alias_set (ao_ref
*ref
)
476 if (ref
->base_alias_set
!= -1)
477 return ref
->base_alias_set
;
478 ref
->base_alias_set
= get_alias_set (ao_ref_base (ref
));
479 return ref
->base_alias_set
;
482 /* Returns the reference alias set of the memory reference *REF. */
485 ao_ref_alias_set (ao_ref
*ref
)
487 if (ref
->ref_alias_set
!= -1)
488 return ref
->ref_alias_set
;
489 ref
->ref_alias_set
= get_alias_set (ref
->ref
);
490 return ref
->ref_alias_set
;
493 /* Init an alias-oracle reference representation from a gimple pointer
494 PTR and a gimple size SIZE in bytes. If SIZE is NULL_TREE the the
495 size is assumed to be unknown. The access is assumed to be only
496 to or after of the pointer target, not before it. */
499 ao_ref_init_from_ptr_and_size (ao_ref
*ref
, tree ptr
, tree size
)
501 HOST_WIDE_INT t1
, t2
;
502 ref
->ref
= NULL_TREE
;
503 if (TREE_CODE (ptr
) == ADDR_EXPR
)
504 ref
->base
= get_ref_base_and_extent (TREE_OPERAND (ptr
, 0),
505 &ref
->offset
, &t1
, &t2
);
508 ref
->base
= build1 (INDIRECT_REF
, char_type_node
, ptr
);
512 && host_integerp (size
, 0)
513 && TREE_INT_CST_LOW (size
) * 8 / 8 == TREE_INT_CST_LOW (size
))
514 ref
->max_size
= ref
->size
= TREE_INT_CST_LOW (size
) * 8;
516 ref
->max_size
= ref
->size
= -1;
517 ref
->ref_alias_set
= 0;
518 ref
->base_alias_set
= 0;
521 /* Return 1 if TYPE1 and TYPE2 are to be considered equivalent for the
522 purpose of TBAA. Return 0 if they are distinct and -1 if we cannot
526 same_type_for_tbaa (tree type1
, tree type2
)
528 type1
= TYPE_MAIN_VARIANT (type1
);
529 type2
= TYPE_MAIN_VARIANT (type2
);
531 /* If we would have to do structural comparison bail out. */
532 if (TYPE_STRUCTURAL_EQUALITY_P (type1
)
533 || TYPE_STRUCTURAL_EQUALITY_P (type2
))
536 /* Compare the canonical types. */
537 if (TYPE_CANONICAL (type1
) == TYPE_CANONICAL (type2
))
540 /* ??? Array types are not properly unified in all cases as we have
541 spurious changes in the index types for example. Removing this
542 causes all sorts of problems with the Fortran frontend. */
543 if (TREE_CODE (type1
) == ARRAY_TYPE
544 && TREE_CODE (type2
) == ARRAY_TYPE
)
547 /* The types are known to be not equal. */
551 /* Determine if the two component references REF1 and REF2 which are
552 based on access types TYPE1 and TYPE2 and of which at least one is based
553 on an indirect reference may alias. */
556 nonaliasing_component_refs_p (tree ref1
, tree type1
,
557 HOST_WIDE_INT offset1
, HOST_WIDE_INT max_size1
,
558 tree ref2
, tree type2
,
559 HOST_WIDE_INT offset2
, HOST_WIDE_INT max_size2
)
561 /* If one reference is a component references through pointers try to find a
562 common base and apply offset based disambiguation. This handles
564 struct A { int i; int j; } *q;
565 struct B { struct A a; int k; } *p;
566 disambiguating q->i and p->a.j. */
570 /* Now search for the type1 in the access path of ref2. This
571 would be a common base for doing offset based disambiguation on. */
573 while (handled_component_p (*refp
)
574 && same_type_for_tbaa (TREE_TYPE (*refp
), type1
) == 0)
575 refp
= &TREE_OPERAND (*refp
, 0);
576 same_p
= same_type_for_tbaa (TREE_TYPE (*refp
), type1
);
577 /* If we couldn't compare types we have to bail out. */
580 else if (same_p
== 1)
582 HOST_WIDE_INT offadj
, sztmp
, msztmp
;
583 get_ref_base_and_extent (*refp
, &offadj
, &sztmp
, &msztmp
);
585 return ranges_overlap_p (offset1
, max_size1
, offset2
, max_size2
);
587 /* If we didn't find a common base, try the other way around. */
589 while (handled_component_p (*refp
)
590 && same_type_for_tbaa (TREE_TYPE (*refp
), type2
) == 0)
591 refp
= &TREE_OPERAND (*refp
, 0);
592 same_p
= same_type_for_tbaa (TREE_TYPE (*refp
), type2
);
593 /* If we couldn't compare types we have to bail out. */
596 else if (same_p
== 1)
598 HOST_WIDE_INT offadj
, sztmp
, msztmp
;
599 get_ref_base_and_extent (*refp
, &offadj
, &sztmp
, &msztmp
);
601 return ranges_overlap_p (offset1
, max_size1
, offset2
, max_size2
);
603 /* If we have two type access paths B1.path1 and B2.path2 they may
604 only alias if either B1 is in B2.path2 or B2 is in B1.path1. */
608 /* Return true if two memory references based on the variables BASE1
609 and BASE2 constrained to [OFFSET1, OFFSET1 + MAX_SIZE1) and
610 [OFFSET2, OFFSET2 + MAX_SIZE2) may alias. */
613 decl_refs_may_alias_p (tree base1
,
614 HOST_WIDE_INT offset1
, HOST_WIDE_INT max_size1
,
616 HOST_WIDE_INT offset2
, HOST_WIDE_INT max_size2
)
618 gcc_assert (SSA_VAR_P (base1
) && SSA_VAR_P (base2
));
620 /* If both references are based on different variables, they cannot alias. */
621 if (!operand_equal_p (base1
, base2
, 0))
624 /* If both references are based on the same variable, they cannot alias if
625 the accesses do not overlap. */
626 return ranges_overlap_p (offset1
, max_size1
, offset2
, max_size2
);
629 /* Return true if an indirect reference based on *PTR1 constrained
630 to [OFFSET1, OFFSET1 + MAX_SIZE1) may alias a variable based on BASE2
631 constrained to [OFFSET2, OFFSET2 + MAX_SIZE2). *PTR1 and BASE2 have
632 the alias sets BASE1_ALIAS_SET and BASE2_ALIAS_SET which can be -1
633 in which case they are computed on-demand. REF1 and REF2
634 if non-NULL are the complete memory reference trees. */
637 indirect_ref_may_alias_decl_p (tree ref1
, tree ptr1
,
638 HOST_WIDE_INT offset1
, HOST_WIDE_INT max_size1
,
639 alias_set_type base1_alias_set
,
640 tree ref2
, tree base2
,
641 HOST_WIDE_INT offset2
, HOST_WIDE_INT max_size2
,
642 alias_set_type base2_alias_set
)
644 /* If only one reference is based on a variable, they cannot alias if
645 the pointer access is beyond the extent of the variable access.
646 (the pointer base cannot validly point to an offset less than zero
648 They also cannot alias if the pointer may not point to the decl. */
650 && !ranges_overlap_p (offset1
, max_size1
, 0, offset2
+ max_size2
))
652 if (!ptr_deref_may_alias_decl_p (ptr1
, base2
))
655 /* Disambiguations that rely on strict aliasing rules follow. */
656 if (!flag_strict_aliasing
)
659 /* If the alias set for a pointer access is zero all bets are off. */
660 if (base1_alias_set
== -1)
661 base1_alias_set
= get_deref_alias_set (ptr1
);
662 if (base1_alias_set
== 0)
664 if (base2_alias_set
== -1)
665 base2_alias_set
= get_alias_set (base2
);
667 /* If both references are through the same type, they do not alias
668 if the accesses do not overlap. This does extra disambiguation
669 for mixed/pointer accesses but requires strict aliasing. */
670 if (same_type_for_tbaa (TREE_TYPE (TREE_TYPE (ptr1
)),
671 TREE_TYPE (base2
)) == 1)
672 return ranges_overlap_p (offset1
, max_size1
, offset2
, max_size2
);
674 /* The only way to access a variable is through a pointer dereference
675 of the same alias set or a subset of it. */
676 if (base1_alias_set
!= base2_alias_set
677 && !alias_set_subset_of (base1_alias_set
, base2_alias_set
))
680 /* Do access-path based disambiguation. */
682 && handled_component_p (ref1
)
683 && handled_component_p (ref2
))
684 return nonaliasing_component_refs_p (ref1
, TREE_TYPE (TREE_TYPE (ptr1
)),
686 ref2
, TREE_TYPE (base2
),
692 /* Return true if two indirect references based on *PTR1
693 and *PTR2 constrained to [OFFSET1, OFFSET1 + MAX_SIZE1) and
694 [OFFSET2, OFFSET2 + MAX_SIZE2) may alias. *PTR1 and *PTR2 have
695 the alias sets BASE1_ALIAS_SET and BASE2_ALIAS_SET which can be -1
696 in which case they are computed on-demand. REF1 and REF2
697 if non-NULL are the complete memory reference trees. */
700 indirect_refs_may_alias_p (tree ref1
, tree ptr1
,
701 HOST_WIDE_INT offset1
, HOST_WIDE_INT max_size1
,
702 alias_set_type base1_alias_set
,
703 tree ref2
, tree ptr2
,
704 HOST_WIDE_INT offset2
, HOST_WIDE_INT max_size2
,
705 alias_set_type base2_alias_set
)
707 /* If both bases are based on pointers they cannot alias if they may not
708 point to the same memory object or if they point to the same object
709 and the accesses do not overlap. */
710 if (operand_equal_p (ptr1
, ptr2
, 0))
711 return ranges_overlap_p (offset1
, max_size1
, offset2
, max_size2
);
712 if (!ptr_derefs_may_alias_p (ptr1
, ptr2
))
715 /* Disambiguations that rely on strict aliasing rules follow. */
716 if (!flag_strict_aliasing
)
719 /* If the alias set for a pointer access is zero all bets are off. */
720 if (base1_alias_set
== -1)
721 base1_alias_set
= get_deref_alias_set (ptr1
);
722 if (base1_alias_set
== 0)
724 if (base2_alias_set
== -1)
725 base2_alias_set
= get_deref_alias_set (ptr2
);
726 if (base2_alias_set
== 0)
729 /* If both references are through the same type, they do not alias
730 if the accesses do not overlap. This does extra disambiguation
731 for mixed/pointer accesses but requires strict aliasing. */
732 if (same_type_for_tbaa (TREE_TYPE (TREE_TYPE (ptr1
)),
733 TREE_TYPE (TREE_TYPE (ptr2
))) == 1)
734 return ranges_overlap_p (offset1
, max_size1
, offset2
, max_size2
);
736 /* Do type-based disambiguation. */
737 if (base1_alias_set
!= base2_alias_set
738 && !alias_sets_conflict_p (base1_alias_set
, base2_alias_set
))
741 /* Do access-path based disambiguation. */
743 && handled_component_p (ref1
)
744 && handled_component_p (ref2
))
745 return nonaliasing_component_refs_p (ref1
, TREE_TYPE (TREE_TYPE (ptr1
)),
747 ref2
, TREE_TYPE (TREE_TYPE (ptr2
)),
753 /* Return true, if the two memory references REF1 and REF2 may alias. */
756 refs_may_alias_p_1 (ao_ref
*ref1
, ao_ref
*ref2
, bool tbaa_p
)
759 HOST_WIDE_INT offset1
= 0, offset2
= 0;
760 HOST_WIDE_INT size1
= -1, size2
= -1;
761 HOST_WIDE_INT max_size1
= -1, max_size2
= -1;
762 bool var1_p
, var2_p
, ind1_p
, ind2_p
;
765 gcc_assert ((!ref1
->ref
766 || SSA_VAR_P (ref1
->ref
)
767 || handled_component_p (ref1
->ref
)
768 || INDIRECT_REF_P (ref1
->ref
)
769 || TREE_CODE (ref1
->ref
) == TARGET_MEM_REF
)
771 || SSA_VAR_P (ref2
->ref
)
772 || handled_component_p (ref2
->ref
)
773 || INDIRECT_REF_P (ref2
->ref
)
774 || TREE_CODE (ref2
->ref
) == TARGET_MEM_REF
));
776 /* Decompose the references into their base objects and the access. */
777 base1
= ao_ref_base (ref1
);
778 offset1
= ref1
->offset
;
780 max_size1
= ref1
->max_size
;
781 base2
= ao_ref_base (ref2
);
782 offset2
= ref2
->offset
;
784 max_size2
= ref2
->max_size
;
786 /* We can end up with registers or constants as bases for example from
787 *D.1663_44 = VIEW_CONVERT_EXPR<struct DB_LSN>(__tmp$B0F64_59);
788 which is seen as a struct copy. */
789 if (TREE_CODE (base1
) == SSA_NAME
790 || TREE_CODE (base2
) == SSA_NAME
791 || is_gimple_min_invariant (base1
)
792 || is_gimple_min_invariant (base2
))
795 /* We can end up refering to code via function decls. As we likely
796 do not properly track code aliases conservatively bail out. */
797 if (TREE_CODE (base1
) == FUNCTION_DECL
798 || TREE_CODE (base2
) == FUNCTION_DECL
)
801 /* Defer to simple offset based disambiguation if we have
802 references based on two decls. Do this before defering to
803 TBAA to handle must-alias cases in conformance with the
804 GCC extension of allowing type-punning through unions. */
805 var1_p
= SSA_VAR_P (base1
);
806 var2_p
= SSA_VAR_P (base2
);
807 if (var1_p
&& var2_p
)
808 return decl_refs_may_alias_p (base1
, offset1
, max_size1
,
809 base2
, offset2
, max_size2
);
811 /* First defer to TBAA if possible. */
813 && flag_strict_aliasing
814 && !alias_sets_conflict_p (ao_ref_alias_set (ref1
),
815 ao_ref_alias_set (ref2
)))
818 /* If one reference is a TARGET_MEM_REF weird things are allowed. Still
819 TBAA disambiguation based on the access type is possible, so bail
820 out only after that check. */
821 if ((ref1
->ref
&& TREE_CODE (ref1
->ref
) == TARGET_MEM_REF
)
822 || (ref2
->ref
&& TREE_CODE (ref2
->ref
) == TARGET_MEM_REF
))
825 /* Dispatch to the pointer-vs-decl or pointer-vs-pointer disambiguators. */
826 ind1_p
= INDIRECT_REF_P (base1
);
827 ind2_p
= INDIRECT_REF_P (base2
);
828 set
= tbaa_p
? -1 : 0;
829 if (var1_p
&& ind2_p
)
830 return indirect_ref_may_alias_decl_p (ref2
->ref
, TREE_OPERAND (base2
, 0),
831 offset2
, max_size2
, set
,
833 offset1
, max_size1
, set
);
834 else if (ind1_p
&& var2_p
)
835 return indirect_ref_may_alias_decl_p (ref1
->ref
, TREE_OPERAND (base1
, 0),
836 offset1
, max_size1
, set
,
838 offset2
, max_size2
, set
);
839 else if (ind1_p
&& ind2_p
)
840 return indirect_refs_may_alias_p (ref1
->ref
, TREE_OPERAND (base1
, 0),
841 offset1
, max_size1
, set
,
842 ref2
->ref
, TREE_OPERAND (base2
, 0),
843 offset2
, max_size2
, set
);
849 refs_may_alias_p (tree ref1
, tree ref2
)
853 ao_ref_init (&r1
, ref1
);
854 ao_ref_init (&r2
, ref2
);
855 res
= refs_may_alias_p_1 (&r1
, &r2
, true);
857 ++alias_stats
.refs_may_alias_p_may_alias
;
859 ++alias_stats
.refs_may_alias_p_no_alias
;
863 /* Returns true if there is a anti-dependence for the STORE that
864 executes after the LOAD. */
867 refs_anti_dependent_p (tree load
, tree store
)
870 ao_ref_init (&r1
, load
);
871 ao_ref_init (&r2
, store
);
872 return refs_may_alias_p_1 (&r1
, &r2
, false);
875 /* Returns true if there is a output dependence for the stores
876 STORE1 and STORE2. */
879 refs_output_dependent_p (tree store1
, tree store2
)
882 ao_ref_init (&r1
, store1
);
883 ao_ref_init (&r2
, store2
);
884 return refs_may_alias_p_1 (&r1
, &r2
, false);
887 /* If the call CALL may use the memory reference REF return true,
888 otherwise return false. */
891 ref_maybe_used_by_call_p_1 (gimple call
, ao_ref
*ref
)
895 int flags
= gimple_call_flags (call
);
897 /* Const functions without a static chain do not implicitly use memory. */
898 if (!gimple_call_chain (call
)
899 && (flags
& (ECF_CONST
|ECF_NOVOPS
)))
902 base
= ao_ref_base (ref
);
906 /* If the reference is based on a decl that is not aliased the call
907 cannot possibly use it. */
909 && !may_be_aliased (base
)
910 /* But local statics can be used through recursion. */
911 && !is_global_var (base
))
914 callee
= gimple_call_fndecl (call
);
916 /* Handle those builtin functions explicitly that do not act as
917 escape points. See tree-ssa-structalias.c:find_func_aliases
918 for the list of builtins we might need to handle here. */
919 if (callee
!= NULL_TREE
920 && DECL_BUILT_IN_CLASS (callee
) == BUILT_IN_NORMAL
)
921 switch (DECL_FUNCTION_CODE (callee
))
923 /* All the following functions clobber memory pointed to by
924 their first argument. */
925 case BUILT_IN_STRCPY
:
926 case BUILT_IN_STRNCPY
:
928 case BUILT_IN_MEMCPY
:
929 case BUILT_IN_MEMMOVE
:
930 case BUILT_IN_MEMPCPY
:
931 case BUILT_IN_STPCPY
:
932 case BUILT_IN_STPNCPY
:
933 case BUILT_IN_STRCAT
:
934 case BUILT_IN_STRNCAT
:
937 tree size
= NULL_TREE
;
938 if (gimple_call_num_args (call
) == 3)
939 size
= gimple_call_arg (call
, 2);
940 ao_ref_init_from_ptr_and_size (&dref
,
941 gimple_call_arg (call
, 1),
943 return refs_may_alias_p_1 (&dref
, ref
, false);
945 /* The following builtins do not read from memory. */
947 case BUILT_IN_MEMSET
:
949 case BUILT_IN_FREXPF
:
950 case BUILT_IN_FREXPL
:
951 case BUILT_IN_GAMMA_R
:
952 case BUILT_IN_GAMMAF_R
:
953 case BUILT_IN_GAMMAL_R
:
954 case BUILT_IN_LGAMMA_R
:
955 case BUILT_IN_LGAMMAF_R
:
956 case BUILT_IN_LGAMMAL_R
:
960 case BUILT_IN_REMQUO
:
961 case BUILT_IN_REMQUOF
:
962 case BUILT_IN_REMQUOL
:
963 case BUILT_IN_SINCOS
:
964 case BUILT_IN_SINCOSF
:
965 case BUILT_IN_SINCOSL
:
969 /* Fallthru to general call handling. */;
972 /* Check if base is a global static variable that is not read
974 if (TREE_CODE (base
) == VAR_DECL
975 && TREE_STATIC (base
)
976 && !TREE_PUBLIC (base
))
980 if (callee
!= NULL_TREE
982 = ipa_reference_get_not_read_global (cgraph_node (callee
)))
983 && bitmap_bit_p (not_read
, DECL_UID (base
)))
987 /* If the base variable is call-used or call-clobbered then
989 if (flags
& (ECF_PURE
|ECF_CONST
|ECF_LOOPING_CONST_OR_PURE
|ECF_NOVOPS
))
993 if (is_call_used (base
))
996 else if (INDIRECT_REF_P (base
)
997 && TREE_CODE (TREE_OPERAND (base
, 0)) == SSA_NAME
)
999 struct ptr_info_def
*pi
= SSA_NAME_PTR_INFO (TREE_OPERAND (base
, 0));
1003 if (pt_solution_includes_global (&pi
->pt
)
1004 || pt_solutions_intersect (&cfun
->gimple_df
->callused
, &pi
->pt
)
1005 || pt_solutions_intersect (&cfun
->gimple_df
->escaped
, &pi
->pt
))
1015 if (is_call_clobbered (base
))
1018 else if (INDIRECT_REF_P (base
)
1019 && TREE_CODE (TREE_OPERAND (base
, 0)) == SSA_NAME
)
1021 struct ptr_info_def
*pi
= SSA_NAME_PTR_INFO (TREE_OPERAND (base
, 0));
1025 if (pt_solution_includes_global (&pi
->pt
)
1026 || pt_solutions_intersect (&cfun
->gimple_df
->escaped
, &pi
->pt
))
1033 /* Inspect call arguments for passed-by-value aliases. */
1035 for (i
= 0; i
< gimple_call_num_args (call
); ++i
)
1037 tree op
= gimple_call_arg (call
, i
);
1039 if (TREE_CODE (op
) == WITH_SIZE_EXPR
)
1040 op
= TREE_OPERAND (op
, 0);
1042 if (TREE_CODE (op
) != SSA_NAME
1043 && !is_gimple_min_invariant (op
))
1046 ao_ref_init (&r
, op
);
1047 if (refs_may_alias_p_1 (&r
, ref
, true))
1056 ref_maybe_used_by_call_p (gimple call
, tree ref
)
1060 ao_ref_init (&r
, ref
);
1061 res
= ref_maybe_used_by_call_p_1 (call
, &r
);
1063 ++alias_stats
.ref_maybe_used_by_call_p_may_alias
;
1065 ++alias_stats
.ref_maybe_used_by_call_p_no_alias
;
1070 /* If the statement STMT may use the memory reference REF return
1071 true, otherwise return false. */
1074 ref_maybe_used_by_stmt_p (gimple stmt
, tree ref
)
1076 if (is_gimple_assign (stmt
))
1080 /* All memory assign statements are single. */
1081 if (!gimple_assign_single_p (stmt
))
1084 rhs
= gimple_assign_rhs1 (stmt
);
1085 if (is_gimple_reg (rhs
)
1086 || is_gimple_min_invariant (rhs
)
1087 || gimple_assign_rhs_code (stmt
) == CONSTRUCTOR
)
1090 return refs_may_alias_p (rhs
, ref
);
1092 else if (is_gimple_call (stmt
))
1093 return ref_maybe_used_by_call_p (stmt
, ref
);
1098 /* If the call in statement CALL may clobber the memory reference REF
1099 return true, otherwise return false. */
1102 call_may_clobber_ref_p_1 (gimple call
, ao_ref
*ref
)
1107 /* If the call is pure or const it cannot clobber anything. */
1108 if (gimple_call_flags (call
)
1109 & (ECF_PURE
|ECF_CONST
|ECF_LOOPING_CONST_OR_PURE
|ECF_NOVOPS
))
1112 base
= ao_ref_base (ref
);
1116 if (TREE_CODE (base
) == SSA_NAME
1117 || CONSTANT_CLASS_P (base
))
1120 /* If the reference is based on a decl that is not aliased the call
1121 cannot possibly clobber it. */
1123 && !may_be_aliased (base
)
1124 /* But local non-readonly statics can be modified through recursion
1125 or the call may implement a threading barrier which we must
1126 treat as may-def. */
1127 && (TREE_READONLY (base
)
1128 || !is_global_var (base
)))
1131 callee
= gimple_call_fndecl (call
);
1133 /* Handle those builtin functions explicitly that do not act as
1134 escape points. See tree-ssa-structalias.c:find_func_aliases
1135 for the list of builtins we might need to handle here. */
1136 if (callee
!= NULL_TREE
1137 && DECL_BUILT_IN_CLASS (callee
) == BUILT_IN_NORMAL
)
1138 switch (DECL_FUNCTION_CODE (callee
))
1140 /* All the following functions clobber memory pointed to by
1141 their first argument. */
1142 case BUILT_IN_STRCPY
:
1143 case BUILT_IN_STRNCPY
:
1144 case BUILT_IN_BCOPY
:
1145 case BUILT_IN_MEMCPY
:
1146 case BUILT_IN_MEMMOVE
:
1147 case BUILT_IN_MEMPCPY
:
1148 case BUILT_IN_STPCPY
:
1149 case BUILT_IN_STPNCPY
:
1150 case BUILT_IN_STRCAT
:
1151 case BUILT_IN_STRNCAT
:
1152 case BUILT_IN_MEMSET
:
1155 tree size
= NULL_TREE
;
1156 if (gimple_call_num_args (call
) == 3)
1157 size
= gimple_call_arg (call
, 2);
1158 ao_ref_init_from_ptr_and_size (&dref
,
1159 gimple_call_arg (call
, 0),
1161 return refs_may_alias_p_1 (&dref
, ref
, false);
1163 /* Freeing memory kills the pointed-to memory. More importantly
1164 the call has to serve as a barrier for moving loads and stores
1168 tree ptr
= gimple_call_arg (call
, 0);
1169 return ptr_deref_may_alias_ref_p_1 (ptr
, ref
);
1171 case BUILT_IN_GAMMA_R
:
1172 case BUILT_IN_GAMMAF_R
:
1173 case BUILT_IN_GAMMAL_R
:
1174 case BUILT_IN_LGAMMA_R
:
1175 case BUILT_IN_LGAMMAF_R
:
1176 case BUILT_IN_LGAMMAL_R
:
1178 tree out
= gimple_call_arg (call
, 1);
1179 if (ptr_deref_may_alias_ref_p_1 (out
, ref
))
1181 if (flag_errno_math
)
1185 case BUILT_IN_FREXP
:
1186 case BUILT_IN_FREXPF
:
1187 case BUILT_IN_FREXPL
:
1189 case BUILT_IN_MODFF
:
1190 case BUILT_IN_MODFL
:
1192 tree out
= gimple_call_arg (call
, 1);
1193 return ptr_deref_may_alias_ref_p_1 (out
, ref
);
1195 case BUILT_IN_REMQUO
:
1196 case BUILT_IN_REMQUOF
:
1197 case BUILT_IN_REMQUOL
:
1199 tree out
= gimple_call_arg (call
, 2);
1200 if (ptr_deref_may_alias_ref_p_1 (out
, ref
))
1202 if (flag_errno_math
)
1206 case BUILT_IN_SINCOS
:
1207 case BUILT_IN_SINCOSF
:
1208 case BUILT_IN_SINCOSL
:
1210 tree sin
= gimple_call_arg (call
, 1);
1211 tree cos
= gimple_call_arg (call
, 2);
1212 return (ptr_deref_may_alias_ref_p_1 (sin
, ref
)
1213 || ptr_deref_may_alias_ref_p_1 (cos
, ref
));
1216 /* Fallthru to general call handling. */;
1219 /* Check if base is a global static variable that is not written
1221 if (callee
!= NULL_TREE
1222 && TREE_CODE (base
) == VAR_DECL
1223 && TREE_STATIC (base
)
1224 && !TREE_PUBLIC (base
))
1229 = ipa_reference_get_not_written_global (cgraph_node (callee
)))
1230 && bitmap_bit_p (not_written
, DECL_UID (base
)))
1235 return is_call_clobbered (base
);
1236 else if (INDIRECT_REF_P (base
)
1237 && TREE_CODE (TREE_OPERAND (base
, 0)) == SSA_NAME
)
1239 struct ptr_info_def
*pi
= SSA_NAME_PTR_INFO (TREE_OPERAND (base
, 0));
1243 return (pt_solution_includes_global (&pi
->pt
)
1244 || pt_solutions_intersect (&cfun
->gimple_df
->escaped
, &pi
->pt
));
1250 static bool ATTRIBUTE_UNUSED
1251 call_may_clobber_ref_p (gimple call
, tree ref
)
1255 ao_ref_init (&r
, ref
);
1256 res
= call_may_clobber_ref_p_1 (call
, &r
);
1258 ++alias_stats
.call_may_clobber_ref_p_may_alias
;
1260 ++alias_stats
.call_may_clobber_ref_p_no_alias
;
1265 /* If the statement STMT may clobber the memory reference REF return true,
1266 otherwise return false. */
1269 stmt_may_clobber_ref_p_1 (gimple stmt
, ao_ref
*ref
)
1271 if (is_gimple_call (stmt
))
1273 tree lhs
= gimple_call_lhs (stmt
);
1275 && !is_gimple_reg (lhs
))
1278 ao_ref_init (&r
, lhs
);
1279 if (refs_may_alias_p_1 (ref
, &r
, true))
1283 return call_may_clobber_ref_p_1 (stmt
, ref
);
1285 else if (is_gimple_assign (stmt
))
1288 ao_ref_init (&r
, gimple_assign_lhs (stmt
));
1289 return refs_may_alias_p_1 (ref
, &r
, true);
1291 else if (gimple_code (stmt
) == GIMPLE_ASM
)
1298 stmt_may_clobber_ref_p (gimple stmt
, tree ref
)
1301 ao_ref_init (&r
, ref
);
1302 return stmt_may_clobber_ref_p_1 (stmt
, &r
);
1306 static tree
get_continuation_for_phi (gimple
, ao_ref
*, bitmap
*);
1308 /* Walk the virtual use-def chain of VUSE until hitting the virtual operand
1309 TARGET or a statement clobbering the memory reference REF in which
1310 case false is returned. The walk starts with VUSE, one argument of PHI. */
1313 maybe_skip_until (gimple phi
, tree target
, ao_ref
*ref
,
1314 tree vuse
, bitmap
*visited
)
1317 *visited
= BITMAP_ALLOC (NULL
);
1319 bitmap_set_bit (*visited
, SSA_NAME_VERSION (PHI_RESULT (phi
)));
1321 /* Walk until we hit the target. */
1322 while (vuse
!= target
)
1324 gimple def_stmt
= SSA_NAME_DEF_STMT (vuse
);
1325 /* Recurse for PHI nodes. */
1326 if (gimple_code (def_stmt
) == GIMPLE_PHI
)
1328 /* An already visited PHI node ends the walk successfully. */
1329 if (bitmap_bit_p (*visited
, SSA_NAME_VERSION (PHI_RESULT (def_stmt
))))
1331 vuse
= get_continuation_for_phi (def_stmt
, ref
, visited
);
1336 /* A clobbering statement or the end of the IL ends it failing. */
1337 else if (gimple_nop_p (def_stmt
)
1338 || stmt_may_clobber_ref_p_1 (def_stmt
, ref
))
1340 vuse
= gimple_vuse (def_stmt
);
1345 /* Starting from a PHI node for the virtual operand of the memory reference
1346 REF find a continuation virtual operand that allows to continue walking
1347 statements dominating PHI skipping only statements that cannot possibly
1348 clobber REF. Returns NULL_TREE if no suitable virtual operand can
1352 get_continuation_for_phi (gimple phi
, ao_ref
*ref
, bitmap
*visited
)
1354 unsigned nargs
= gimple_phi_num_args (phi
);
1356 /* Through a single-argument PHI we can simply look through. */
1358 return PHI_ARG_DEF (phi
, 0);
1360 /* For two arguments try to skip non-aliasing code until we hit
1361 the phi argument definition that dominates the other one. */
1364 tree arg0
= PHI_ARG_DEF (phi
, 0);
1365 tree arg1
= PHI_ARG_DEF (phi
, 1);
1366 gimple def0
= SSA_NAME_DEF_STMT (arg0
);
1367 gimple def1
= SSA_NAME_DEF_STMT (arg1
);
1371 else if (gimple_nop_p (def0
)
1372 || (!gimple_nop_p (def1
)
1373 && dominated_by_p (CDI_DOMINATORS
,
1374 gimple_bb (def1
), gimple_bb (def0
))))
1376 if (maybe_skip_until (phi
, arg0
, ref
, arg1
, visited
))
1379 else if (gimple_nop_p (def1
)
1380 || dominated_by_p (CDI_DOMINATORS
,
1381 gimple_bb (def0
), gimple_bb (def1
)))
1383 if (maybe_skip_until (phi
, arg1
, ref
, arg0
, visited
))
1391 /* Based on the memory reference REF and its virtual use VUSE call
1392 WALKER for each virtual use that is equivalent to VUSE, including VUSE
1393 itself. That is, for each virtual use for which its defining statement
1394 does not clobber REF.
1396 WALKER is called with REF, the current virtual use and DATA. If
1397 WALKER returns non-NULL the walk stops and its result is returned.
1398 At the end of a non-successful walk NULL is returned.
1400 TRANSLATE if non-NULL is called with a pointer to REF, the virtual
1401 use which definition is a statement that may clobber REF and DATA.
1402 If TRANSLATE returns (void *)-1 the walk stops and NULL is returned.
1403 If TRANSLATE returns non-NULL the walk stops and its result is returned.
1404 If TRANSLATE returns NULL the walk continues and TRANSLATE is supposed
1405 to adjust REF and *DATA to make that valid.
1407 TODO: Cache the vector of equivalent vuses per ref, vuse pair. */
1410 walk_non_aliased_vuses (ao_ref
*ref
, tree vuse
,
1411 void *(*walker
)(ao_ref
*, tree
, void *),
1412 void *(*translate
)(ao_ref
*, tree
, void *), void *data
)
1414 bitmap visited
= NULL
;
1417 timevar_push (TV_ALIAS_STMT_WALK
);
1423 /* ??? Do we want to account this to TV_ALIAS_STMT_WALK? */
1424 res
= (*walker
) (ref
, vuse
, data
);
1428 def_stmt
= SSA_NAME_DEF_STMT (vuse
);
1429 if (gimple_nop_p (def_stmt
))
1431 else if (gimple_code (def_stmt
) == GIMPLE_PHI
)
1432 vuse
= get_continuation_for_phi (def_stmt
, ref
, &visited
);
1435 if (stmt_may_clobber_ref_p_1 (def_stmt
, ref
))
1439 res
= (*translate
) (ref
, vuse
, data
);
1440 /* Failed lookup and translation. */
1441 if (res
== (void *)-1)
1446 /* Lookup succeeded. */
1447 else if (res
!= NULL
)
1449 /* Translation succeeded, continue walking. */
1451 vuse
= gimple_vuse (def_stmt
);
1457 BITMAP_FREE (visited
);
1459 timevar_pop (TV_ALIAS_STMT_WALK
);
1465 /* Based on the memory reference REF call WALKER for each vdef which
1466 defining statement may clobber REF, starting with VDEF. If REF
1467 is NULL_TREE, each defining statement is visited.
1469 WALKER is called with REF, the current vdef and DATA. If WALKER
1470 returns true the walk is stopped, otherwise it continues.
1472 At PHI nodes walk_aliased_vdefs forks into one walk for reach
1473 PHI argument (but only one walk continues on merge points), the
1474 return value is true if any of the walks was successful.
1476 The function returns the number of statements walked. */
1479 walk_aliased_vdefs_1 (ao_ref
*ref
, tree vdef
,
1480 bool (*walker
)(ao_ref
*, tree
, void *), void *data
,
1481 bitmap
*visited
, unsigned int cnt
)
1485 gimple def_stmt
= SSA_NAME_DEF_STMT (vdef
);
1488 && !bitmap_set_bit (*visited
, SSA_NAME_VERSION (vdef
)))
1491 if (gimple_nop_p (def_stmt
))
1493 else if (gimple_code (def_stmt
) == GIMPLE_PHI
)
1497 *visited
= BITMAP_ALLOC (NULL
);
1498 for (i
= 0; i
< gimple_phi_num_args (def_stmt
); ++i
)
1499 cnt
+= walk_aliased_vdefs_1 (ref
, gimple_phi_arg_def (def_stmt
, i
),
1500 walker
, data
, visited
, 0);
1504 /* ??? Do we want to account this to TV_ALIAS_STMT_WALK? */
1507 || stmt_may_clobber_ref_p_1 (def_stmt
, ref
))
1508 && (*walker
) (ref
, vdef
, data
))
1511 vdef
= gimple_vuse (def_stmt
);
1517 walk_aliased_vdefs (ao_ref
*ref
, tree vdef
,
1518 bool (*walker
)(ao_ref
*, tree
, void *), void *data
,
1521 bitmap local_visited
= NULL
;
1524 timevar_push (TV_ALIAS_STMT_WALK
);
1526 ret
= walk_aliased_vdefs_1 (ref
, vdef
, walker
, data
,
1527 visited
? visited
: &local_visited
, 0);
1529 BITMAP_FREE (local_visited
);
1531 timevar_pop (TV_ALIAS_STMT_WALK
);