1 /* SSA operands management for trees.
2 Copyright (C) 2003, 2004, 2005 Free Software Foundation, Inc.
4 This file is part of GCC.
6 GCC is free software; you can redistribute it and/or modify
7 it under the terms of the GNU General Public License as published by
8 the Free Software Foundation; either version 2, or (at your option)
11 GCC is distributed in the hope that it will be useful,
12 but WITHOUT ANY WARRANTY; without even the implied warranty of
13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 GNU General Public License for more details.
16 You should have received a copy of the GNU General Public License
17 along with GCC; see the file COPYING. If not, write to
18 the Free Software Foundation, 59 Temple Place - Suite 330,
19 Boston, MA 02111-1307, USA. */
23 #include "coretypes.h"
28 #include "diagnostic.h"
29 #include "tree-flow.h"
30 #include "tree-inline.h"
31 #include "tree-pass.h"
36 #include "langhooks.h"
38 /* This file contains the code required to manage the operands cache of the
39 SSA optimizer. For every stmt, we maintain an operand cache in the stmt
40 annotation. This cache contains operands that will be of interest to
41 optimizers and other passes wishing to manipulate the IL.
43 The operand type are broken up into REAL and VIRTUAL operands. The real
44 operands are represented as pointers into the stmt's operand tree. Thus
45 any manipulation of the real operands will be reflected in the actual tree.
46 Virtual operands are represented solely in the cache, although the base
47 variable for the SSA_NAME may, or may not occur in the stmt's tree.
48 Manipulation of the virtual operands will not be reflected in the stmt tree.
50 The routines in this file are concerned with creating this operand cache
53 The operand tree is the parsed by the various get_* routines which look
54 through the stmt tree for the occurrence of operands which may be of
55 interest, and calls are made to the append_* routines whenever one is
56 found. There are 5 of these routines, each representing one of the
57 5 types of operands. Defs, Uses, Virtual Uses, Virtual May Defs, and
60 The append_* routines check for duplication, and simply keep a list of
61 unique objects for each operand type in the build_* extendable vectors.
63 Once the stmt tree is completely parsed, the finalize_ssa_operands()
64 routine is called, which proceeds to perform the finalization routine
65 on each of the 5 operand vectors which have been built up.
67 If the stmt had a previous operand cache, the finalization routines
68 attempt to match up the new operands with the old ones. If it's a perfect
69 match, the old vector is simply reused. If it isn't a perfect match, then
70 a new vector is created and the new operands are placed there. For
71 virtual operands, if the previous cache had SSA_NAME version of a
72 variable, and that same variable occurs in the same operands cache, then
73 the new cache vector will also get the same SSA_NAME.
75 i.e., if a stmt had a VUSE of 'a_5', and 'a' occurs in the new operand
76 vector for VUSE, then the new vector will also be modified such that
77 it contains 'a_5' rather than 'a'.
82 /* Flags to describe operand properties in helpers. */
84 /* By default, operands are loaded. */
87 /* Operand is the target of an assignment expression or a
88 call-clobbered variable */
89 #define opf_is_def (1 << 0)
91 /* Operand is the target of an assignment expression. */
92 #define opf_kill_def (1 << 1)
94 /* No virtual operands should be created in the expression. This is used
95 when traversing ADDR_EXPR nodes which have different semantics than
96 other expressions. Inside an ADDR_EXPR node, the only operands that we
97 need to consider are indices into arrays. For instance, &a.b[i] should
98 generate a USE of 'i' but it should not generate a VUSE for 'a' nor a
100 #define opf_no_vops (1 << 2)
102 /* Operand is a "non-specific" kill for call-clobbers and such. This is used
103 to distinguish "reset the world" events from explicit MODIFY_EXPRs. */
104 #define opf_non_specific (1 << 3)
106 /* This structure maintain a sorted list of operands which is created by
107 parse_ssa_operand. */
108 struct opbuild_list_d
GTY (())
110 varray_type vars
; /* The VAR_DECLS tree. */
111 varray_type uid
; /* The sort value for virtual symbols. */
112 varray_type next
; /* The next index in the sorted list. */
113 int first
; /* First element in list. */
114 unsigned num
; /* Number of elements. */
117 #define OPBUILD_LAST -1
120 /* Array for building all the def operands. */
121 static GTY (()) struct opbuild_list_d build_defs
;
123 /* Array for building all the use operands. */
124 static GTY (()) struct opbuild_list_d build_uses
;
126 /* Array for building all the v_may_def operands. */
127 static GTY (()) struct opbuild_list_d build_v_may_defs
;
129 /* Array for building all the vuse operands. */
130 static GTY (()) struct opbuild_list_d build_vuses
;
132 /* Array for building all the v_must_def operands. */
133 static GTY (()) struct opbuild_list_d build_v_must_defs
;
135 /* True if the operands for call clobbered vars are cached and valid. */
136 bool ssa_call_clobbered_cache_valid
;
137 bool ssa_ro_call_cache_valid
;
139 /* These arrays are the cached operand vectors for call clobbered calls. */
140 static VEC(tree
,heap
) *clobbered_v_may_defs
;
141 static VEC(tree
,heap
) *clobbered_vuses
;
142 static VEC(tree
,heap
) *ro_call_vuses
;
143 static bool clobbered_aliased_loads
;
144 static bool clobbered_aliased_stores
;
145 static bool ro_call_aliased_loads
;
146 static bool ops_active
= false;
148 static GTY (()) struct ssa_operand_memory_d
*operand_memory
= NULL
;
149 static unsigned operand_memory_index
;
151 static void note_addressable (tree
, stmt_ann_t
);
152 static void get_expr_operands (tree
, tree
*, int);
153 static void get_asm_expr_operands (tree
);
154 static void get_indirect_ref_operands (tree
, tree
, int);
155 static void get_tmr_operands (tree
, tree
, int);
156 static void get_call_expr_operands (tree
, tree
);
157 static inline void append_def (tree
*);
158 static inline void append_use (tree
*);
159 static void append_v_may_def (tree
);
160 static void append_v_must_def (tree
);
161 static void add_call_clobber_ops (tree
);
162 static void add_call_read_ops (tree
);
163 static void add_stmt_operand (tree
*, stmt_ann_t
, int);
164 static void build_ssa_operands (tree stmt
);
166 static def_optype_p free_defs
= NULL
;
167 static use_optype_p free_uses
= NULL
;
168 static vuse_optype_p free_vuses
= NULL
;
169 static maydef_optype_p free_maydefs
= NULL
;
170 static mustdef_optype_p free_mustdefs
= NULL
;
172 /* Initialize a virtual operand build LIST called NAME with NUM elements. */
175 opbuild_initialize_virtual (struct opbuild_list_d
*list
, int num
,
178 list
->first
= OPBUILD_LAST
;
180 VARRAY_TREE_INIT (list
->vars
, num
, name
);
181 VARRAY_UINT_INIT (list
->uid
, num
, "List UID");
182 VARRAY_INT_INIT (list
->next
, num
, "List NEXT");
186 /* Initialize a real operand build LIST called NAME with NUM elements. */
189 opbuild_initialize_real (struct opbuild_list_d
*list
, int num
, const char *name
)
191 list
->first
= OPBUILD_LAST
;
193 VARRAY_TREE_PTR_INIT (list
->vars
, num
, name
);
194 VARRAY_INT_INIT (list
->next
, num
, "List NEXT");
195 /* The UID field is not needed since we sort based on the pointer value. */
200 /* Free memory used in virtual operand build object LIST. */
203 opbuild_free (struct opbuild_list_d
*list
)
211 /* Number of elements in an opbuild list. */
213 static inline unsigned
214 opbuild_num_elems (struct opbuild_list_d
*list
)
220 /* Add VAR to the real operand list LIST, keeping it sorted and avoiding
221 duplicates. The actual sort value is the tree pointer value. */
224 opbuild_append_real (struct opbuild_list_d
*list
, tree
*var
)
228 #ifdef ENABLE_CHECKING
229 /* Ensure the real operand doesn't exist already. */
230 for (index
= list
->first
;
231 index
!= OPBUILD_LAST
;
232 index
= VARRAY_INT (list
->next
, index
))
233 gcc_assert (VARRAY_TREE_PTR (list
->vars
, index
) != var
);
236 /* First item in the list. */
237 index
= VARRAY_ACTIVE_SIZE (list
->vars
);
241 VARRAY_INT (list
->next
, index
- 1) = index
;
242 VARRAY_PUSH_INT (list
->next
, OPBUILD_LAST
);
243 VARRAY_PUSH_TREE_PTR (list
->vars
, var
);
248 /* Add VAR to the virtual operand list LIST, keeping it sorted and avoiding
249 duplicates. The actual sort value is the DECL UID of the base variable. */
252 opbuild_append_virtual (struct opbuild_list_d
*list
, tree var
)
254 int index
, curr
, last
;
255 unsigned int var_uid
;
257 if (TREE_CODE (var
) != SSA_NAME
)
258 var_uid
= DECL_UID (var
);
260 var_uid
= DECL_UID (SSA_NAME_VAR (var
));
262 index
= VARRAY_ACTIVE_SIZE (list
->vars
);
266 VARRAY_PUSH_TREE (list
->vars
, var
);
267 VARRAY_PUSH_UINT (list
->uid
, var_uid
);
268 VARRAY_PUSH_INT (list
->next
, OPBUILD_LAST
);
275 /* Find the correct spot in the sorted list. */
276 for (curr
= list
->first
;
277 curr
!= OPBUILD_LAST
;
278 last
= curr
, curr
= VARRAY_INT (list
->next
, curr
))
280 if (VARRAY_UINT (list
->uid
, curr
) > var_uid
)
284 if (last
== OPBUILD_LAST
)
286 /* First item in the list. */
287 VARRAY_PUSH_INT (list
->next
, list
->first
);
292 /* Don't enter duplicates at all. */
293 if (VARRAY_UINT (list
->uid
, last
) == var_uid
)
296 VARRAY_PUSH_INT (list
->next
, VARRAY_INT (list
->next
, last
));
297 VARRAY_INT (list
->next
, last
) = index
;
299 VARRAY_PUSH_TREE (list
->vars
, var
);
300 VARRAY_PUSH_UINT (list
->uid
, var_uid
);
305 /* Return the first element index in LIST. OPBUILD_LAST means there are no
309 opbuild_first (struct opbuild_list_d
*list
)
318 /* Return the next element after PREV in LIST. */
321 opbuild_next (struct opbuild_list_d
*list
, int prev
)
323 return VARRAY_INT (list
->next
, prev
);
327 /* Return the real element at index ELEM in LIST. */
330 opbuild_elem_real (struct opbuild_list_d
*list
, int elem
)
332 return VARRAY_TREE_PTR (list
->vars
, elem
);
336 /* Return the virtual element at index ELEM in LIST. */
339 opbuild_elem_virtual (struct opbuild_list_d
*list
, int elem
)
341 return VARRAY_TREE (list
->vars
, elem
);
345 /* Return the virtual element uid at index ELEM in LIST. */
346 static inline unsigned int
347 opbuild_elem_uid (struct opbuild_list_d
*list
, int elem
)
349 return VARRAY_UINT (list
->uid
, elem
);
353 /* Reset an operand build list. */
356 opbuild_clear (struct opbuild_list_d
*list
)
358 list
->first
= OPBUILD_LAST
;
359 VARRAY_POP_ALL (list
->vars
);
360 VARRAY_POP_ALL (list
->next
);
362 VARRAY_POP_ALL (list
->uid
);
367 /* Remove ELEM from LIST where PREV is the previous element. Return the next
371 opbuild_remove_elem (struct opbuild_list_d
*list
, int elem
, int prev
)
374 if (prev
!= OPBUILD_LAST
)
376 gcc_assert (VARRAY_INT (list
->next
, prev
) == elem
);
377 ret
= VARRAY_INT (list
->next
, prev
) = VARRAY_INT (list
->next
, elem
);
381 gcc_assert (list
->first
== elem
);
382 ret
= list
->first
= VARRAY_INT (list
->next
, elem
);
389 /* Return true if the ssa operands cache is active. */
392 ssa_operands_active (void)
398 /* Initialize the operand cache routines. */
401 init_ssa_operands (void)
403 opbuild_initialize_real (&build_defs
, 5, "build defs");
404 opbuild_initialize_real (&build_uses
, 10, "build uses");
405 opbuild_initialize_virtual (&build_vuses
, 25, "build_vuses");
406 opbuild_initialize_virtual (&build_v_may_defs
, 25, "build_v_may_defs");
407 opbuild_initialize_virtual (&build_v_must_defs
, 25, "build_v_must_defs");
408 gcc_assert (operand_memory
== NULL
);
409 operand_memory_index
= SSA_OPERAND_MEMORY_SIZE
;
414 /* Dispose of anything required by the operand routines. */
417 fini_ssa_operands (void)
419 struct ssa_operand_memory_d
*ptr
;
420 opbuild_free (&build_defs
);
421 opbuild_free (&build_uses
);
422 opbuild_free (&build_v_must_defs
);
423 opbuild_free (&build_v_may_defs
);
424 opbuild_free (&build_vuses
);
429 free_mustdefs
= NULL
;
430 while ((ptr
= operand_memory
) != NULL
)
432 operand_memory
= operand_memory
->next
;
436 VEC_free (tree
, heap
, clobbered_v_may_defs
);
437 VEC_free (tree
, heap
, clobbered_vuses
);
438 VEC_free (tree
, heap
, ro_call_vuses
);
443 /* Return memory for operands of SIZE chunks. */
446 ssa_operand_alloc (unsigned size
)
449 if (operand_memory_index
+ size
>= SSA_OPERAND_MEMORY_SIZE
)
451 struct ssa_operand_memory_d
*ptr
;
452 ptr
= ggc_alloc (sizeof (struct ssa_operand_memory_d
));
453 ptr
->next
= operand_memory
;
454 operand_memory
= ptr
;
455 operand_memory_index
= 0;
457 ptr
= &(operand_memory
->mem
[operand_memory_index
]);
458 operand_memory_index
+= size
;
463 /* Make sure PTR is inn the correct immediate use list. Since uses are simply
464 pointers into the stmt TREE, there is no way of telling if anyone has
465 changed what this pointer points to via TREE_OPERANDS (exp, 0) = <...>.
466 THe contents are different, but the the pointer is still the same. This
467 routine will check to make sure PTR is in the correct list, and if it isn't
468 put it in the correct list. We cannot simply check the previous node
469 because all nodes in the same stmt might have be changed. */
472 correct_use_link (use_operand_p ptr
, tree stmt
)
477 /* Fold_stmt () may have changed the stmt pointers. */
478 if (ptr
->stmt
!= stmt
)
484 bool stmt_mod
= true;
485 /* Find the first element which isn't a SAFE iterator, is in a different
486 stmt, and is not a a modified stmt, That node is in the correct list,
487 see if we are too. */
491 while (prev
->stmt
== stmt
|| prev
->stmt
== NULL
)
493 if (prev
->use
== NULL
)
496 if ((stmt_mod
= stmt_modified_p (prev
->stmt
)))
500 /* Get the ssa_name of the list the node is in. */
501 if (prev
->use
== NULL
)
505 /* If it's the right list, simply return. */
506 if (root
== *(ptr
->use
))
509 /* Its in the wrong list if we reach here. */
510 delink_imm_use (ptr
);
511 link_imm_use (ptr
, *(ptr
->use
));
515 #define FINALIZE_OPBUILD build_defs
516 #define FINALIZE_OPBUILD_BASE(I) opbuild_elem_real (&build_defs, (I))
517 #define FINALIZE_OPBUILD_ELEM(I) opbuild_elem_real (&build_defs, (I))
518 #define FINALIZE_FUNC finalize_ssa_def_ops
519 #define FINALIZE_ALLOC alloc_def
520 #define FINALIZE_FREE free_defs
521 #define FINALIZE_TYPE struct def_optype_d
522 #define FINALIZE_ELEM(PTR) ((PTR)->def_ptr)
523 #define FINALIZE_OPS DEF_OPS
524 #define FINALIZE_BASE(VAR) VAR
525 #define FINALIZE_BASE_TYPE tree *
526 #define FINALIZE_BASE_ZERO NULL
527 #define FINALIZE_INITIALIZE(PTR, VAL, STMT) FINALIZE_ELEM (PTR) = (VAL)
528 #include "tree-ssa-opfinalize.h"
531 /* This routine will create stmt operands for STMT from the def build list. */
534 finalize_ssa_defs (tree stmt
)
536 unsigned int num
= opbuild_num_elems (&build_defs
);
537 /* There should only be a single real definition per assignment. */
538 gcc_assert ((stmt
&& TREE_CODE (stmt
) != MODIFY_EXPR
) || num
<= 1);
540 /* If there is an old list, often the new list is identical, or close, so
541 find the elements at the beginning that are the same as the vector. */
543 finalize_ssa_def_ops (stmt
);
544 opbuild_clear (&build_defs
);
547 #define FINALIZE_OPBUILD build_uses
548 #define FINALIZE_OPBUILD_BASE(I) opbuild_elem_real (&build_uses, (I))
549 #define FINALIZE_OPBUILD_ELEM(I) opbuild_elem_real (&build_uses, (I))
550 #define FINALIZE_FUNC finalize_ssa_use_ops
551 #define FINALIZE_ALLOC alloc_use
552 #define FINALIZE_FREE free_uses
553 #define FINALIZE_TYPE struct use_optype_d
554 #define FINALIZE_ELEM(PTR) ((PTR)->use_ptr.use)
555 #define FINALIZE_OPS USE_OPS
556 #define FINALIZE_USE_PTR(PTR) USE_OP_PTR (PTR)
557 #define FINALIZE_BASE(VAR) VAR
558 #define FINALIZE_BASE_TYPE tree *
559 #define FINALIZE_BASE_ZERO NULL
560 #define FINALIZE_INITIALIZE(PTR, VAL, STMT) \
561 (PTR)->use_ptr.use = (VAL); \
562 link_imm_use_stmt (&((PTR)->use_ptr), \
564 #include "tree-ssa-opfinalize.h"
566 /* Return a new use operand vector for STMT, comparing to OLD_OPS_P. */
569 finalize_ssa_uses (tree stmt
)
571 #ifdef ENABLE_CHECKING
574 unsigned num
= opbuild_num_elems (&build_uses
);
576 /* If the pointer to the operand is the statement itself, something is
577 wrong. It means that we are pointing to a local variable (the
578 initial call to get_stmt_operands does not pass a pointer to a
580 for (x
= 0; x
< num
; x
++)
581 gcc_assert (*(opbuild_elem_real (&build_uses
, x
)) != stmt
);
584 finalize_ssa_use_ops (stmt
);
585 opbuild_clear (&build_uses
);
589 /* Return a new v_may_def operand vector for STMT, comparing to OLD_OPS_P. */
590 #define FINALIZE_OPBUILD build_v_may_defs
591 #define FINALIZE_OPBUILD_ELEM(I) opbuild_elem_virtual (&build_v_may_defs, (I))
592 #define FINALIZE_OPBUILD_BASE(I) opbuild_elem_uid (&build_v_may_defs, (I))
593 #define FINALIZE_FUNC finalize_ssa_v_may_def_ops
594 #define FINALIZE_ALLOC alloc_maydef
595 #define FINALIZE_FREE free_maydefs
596 #define FINALIZE_TYPE struct maydef_optype_d
597 #define FINALIZE_ELEM(PTR) MAYDEF_RESULT (PTR)
598 #define FINALIZE_OPS MAYDEF_OPS
599 #define FINALIZE_USE_PTR(PTR) MAYDEF_OP_PTR (PTR)
600 #define FINALIZE_BASE_ZERO 0
601 #define FINALIZE_BASE(VAR) ((TREE_CODE (VAR) == SSA_NAME) \
602 ? DECL_UID (SSA_NAME_VAR (VAR)) : DECL_UID ((VAR)))
603 #define FINALIZE_BASE_TYPE unsigned
604 #define FINALIZE_INITIALIZE(PTR, VAL, STMT) \
605 (PTR)->def_var = (VAL); \
606 (PTR)->use_var = (VAL); \
607 (PTR)->use_ptr.use = &((PTR)->use_var); \
608 link_imm_use_stmt (&((PTR)->use_ptr), \
610 #include "tree-ssa-opfinalize.h"
614 finalize_ssa_v_may_defs (tree stmt
)
616 finalize_ssa_v_may_def_ops (stmt
);
620 /* Clear the in_list bits and empty the build array for v_may_defs. */
623 cleanup_v_may_defs (void)
626 num
= opbuild_num_elems (&build_v_may_defs
);
628 for (x
= 0; x
< num
; x
++)
630 tree t
= opbuild_elem_virtual (&build_v_may_defs
, x
);
631 if (TREE_CODE (t
) != SSA_NAME
)
633 var_ann_t ann
= var_ann (t
);
634 ann
->in_v_may_def_list
= 0;
637 opbuild_clear (&build_v_may_defs
);
641 #define FINALIZE_OPBUILD build_vuses
642 #define FINALIZE_OPBUILD_ELEM(I) opbuild_elem_virtual (&build_vuses, (I))
643 #define FINALIZE_OPBUILD_BASE(I) opbuild_elem_uid (&build_vuses, (I))
644 #define FINALIZE_FUNC finalize_ssa_vuse_ops
645 #define FINALIZE_ALLOC alloc_vuse
646 #define FINALIZE_FREE free_vuses
647 #define FINALIZE_TYPE struct vuse_optype_d
648 #define FINALIZE_ELEM(PTR) VUSE_OP (PTR)
649 #define FINALIZE_OPS VUSE_OPS
650 #define FINALIZE_USE_PTR(PTR) VUSE_OP_PTR (PTR)
651 #define FINALIZE_BASE_ZERO 0
652 #define FINALIZE_BASE(VAR) ((TREE_CODE (VAR) == SSA_NAME) \
653 ? DECL_UID (SSA_NAME_VAR (VAR)) : DECL_UID ((VAR)))
654 #define FINALIZE_BASE_TYPE unsigned
655 #define FINALIZE_INITIALIZE(PTR, VAL, STMT) \
656 (PTR)->use_var = (VAL); \
657 (PTR)->use_ptr.use = &((PTR)->use_var); \
658 link_imm_use_stmt (&((PTR)->use_ptr), \
660 #include "tree-ssa-opfinalize.h"
663 /* Return a new vuse operand vector, comparing to OLD_OPS_P. */
666 finalize_ssa_vuses (tree stmt
)
668 unsigned num
, num_v_may_defs
;
671 /* Remove superfluous VUSE operands. If the statement already has a
672 V_MAY_DEF operation for a variable 'a', then a VUSE for 'a' is not
673 needed because V_MAY_DEFs imply a VUSE of the variable. For instance,
674 suppose that variable 'a' is aliased:
677 # a_3 = V_MAY_DEF <a_2>
680 The VUSE <a_2> is superfluous because it is implied by the V_MAY_DEF
683 num
= opbuild_num_elems (&build_vuses
);
684 num_v_may_defs
= opbuild_num_elems (&build_v_may_defs
);
686 if (num
> 0 && num_v_may_defs
> 0)
688 int last
= OPBUILD_LAST
;
689 vuse_index
= opbuild_first (&build_vuses
);
690 for ( ; vuse_index
!= OPBUILD_LAST
; )
693 vuse
= opbuild_elem_virtual (&build_vuses
, vuse_index
);
694 if (TREE_CODE (vuse
) != SSA_NAME
)
696 var_ann_t ann
= var_ann (vuse
);
697 ann
->in_vuse_list
= 0;
698 if (ann
->in_v_may_def_list
)
700 vuse_index
= opbuild_remove_elem (&build_vuses
, vuse_index
,
706 vuse_index
= opbuild_next (&build_vuses
, vuse_index
);
710 /* Clear out the in_list bits. */
711 for (vuse_index
= opbuild_first (&build_vuses
);
712 vuse_index
!= OPBUILD_LAST
;
713 vuse_index
= opbuild_next (&build_vuses
, vuse_index
))
715 tree t
= opbuild_elem_virtual (&build_vuses
, vuse_index
);
716 if (TREE_CODE (t
) != SSA_NAME
)
718 var_ann_t ann
= var_ann (t
);
719 ann
->in_vuse_list
= 0;
723 finalize_ssa_vuse_ops (stmt
);
724 /* The v_may_def build vector wasn't cleaned up because we needed it. */
725 cleanup_v_may_defs ();
727 /* Free the vuses build vector. */
728 opbuild_clear (&build_vuses
);
732 /* Return a new v_must_def operand vector for STMT, comparing to OLD_OPS_P. */
734 #define FINALIZE_OPBUILD build_v_must_defs
735 #define FINALIZE_OPBUILD_ELEM(I) opbuild_elem_virtual (&build_v_must_defs, (I))
736 #define FINALIZE_OPBUILD_BASE(I) opbuild_elem_uid (&build_v_must_defs, (I))
737 #define FINALIZE_FUNC finalize_ssa_v_must_def_ops
738 #define FINALIZE_ALLOC alloc_mustdef
739 #define FINALIZE_FREE free_mustdefs
740 #define FINALIZE_TYPE struct mustdef_optype_d
741 #define FINALIZE_ELEM(PTR) MUSTDEF_RESULT (PTR)
742 #define FINALIZE_OPS MUSTDEF_OPS
743 #define FINALIZE_USE_PTR(PTR) MUSTDEF_KILL_PTR (PTR)
744 #define FINALIZE_BASE_ZERO 0
745 #define FINALIZE_BASE(VAR) ((TREE_CODE (VAR) == SSA_NAME) \
746 ? DECL_UID (SSA_NAME_VAR (VAR)) : DECL_UID ((VAR)))
747 #define FINALIZE_BASE_TYPE unsigned
748 #define FINALIZE_INITIALIZE(PTR, VAL, STMT) \
749 (PTR)->def_var = (VAL); \
750 (PTR)->kill_var = (VAL); \
751 (PTR)->use_ptr.use = &((PTR)->kill_var);\
752 link_imm_use_stmt (&((PTR)->use_ptr), \
754 #include "tree-ssa-opfinalize.h"
758 finalize_ssa_v_must_defs (tree stmt
)
760 /* In the presence of subvars, there may be more than one V_MUST_DEF per
761 statement (one for each subvar). It is a bit expensive to verify that
762 all must-defs in a statement belong to subvars if there is more than one
763 MUST-def, so we don't do it. Suffice to say, if you reach here without
764 having subvars, and have num >1, you have hit a bug. */
766 finalize_ssa_v_must_def_ops (stmt
);
767 opbuild_clear (&build_v_must_defs
);
771 /* Finalize all the build vectors, fill the new ones into INFO. */
774 finalize_ssa_stmt_operands (tree stmt
)
776 finalize_ssa_defs (stmt
);
777 finalize_ssa_uses (stmt
);
778 finalize_ssa_v_must_defs (stmt
);
779 finalize_ssa_v_may_defs (stmt
);
780 finalize_ssa_vuses (stmt
);
784 /* Start the process of building up operands vectors in INFO. */
787 start_ssa_stmt_operands (void)
789 gcc_assert (opbuild_num_elems (&build_defs
) == 0);
790 gcc_assert (opbuild_num_elems (&build_uses
) == 0);
791 gcc_assert (opbuild_num_elems (&build_vuses
) == 0);
792 gcc_assert (opbuild_num_elems (&build_v_may_defs
) == 0);
793 gcc_assert (opbuild_num_elems (&build_v_must_defs
) == 0);
797 /* Add DEF_P to the list of pointers to operands. */
800 append_def (tree
*def_p
)
802 opbuild_append_real (&build_defs
, def_p
);
806 /* Add USE_P to the list of pointers to operands. */
809 append_use (tree
*use_p
)
811 opbuild_append_real (&build_uses
, use_p
);
815 /* Add a new virtual may def for variable VAR to the build array. */
818 append_v_may_def (tree var
)
820 if (TREE_CODE (var
) != SSA_NAME
)
822 var_ann_t ann
= get_var_ann (var
);
824 /* Don't allow duplicate entries. */
825 if (ann
->in_v_may_def_list
)
827 ann
->in_v_may_def_list
= 1;
830 opbuild_append_virtual (&build_v_may_defs
, var
);
834 /* Add VAR to the list of virtual uses. */
837 append_vuse (tree var
)
840 /* Don't allow duplicate entries. */
841 if (TREE_CODE (var
) != SSA_NAME
)
843 var_ann_t ann
= get_var_ann (var
);
845 if (ann
->in_vuse_list
|| ann
->in_v_may_def_list
)
847 ann
->in_vuse_list
= 1;
850 opbuild_append_virtual (&build_vuses
, var
);
854 /* Add VAR to the list of virtual must definitions for INFO. */
857 append_v_must_def (tree var
)
861 /* Don't allow duplicate entries. */
862 for (i
= 0; i
< opbuild_num_elems (&build_v_must_defs
); i
++)
863 if (var
== opbuild_elem_virtual (&build_v_must_defs
, i
))
866 opbuild_append_virtual (&build_v_must_defs
, var
);
870 /* Parse STMT looking for operands. OLD_OPS is the original stmt operand
871 cache for STMT, if it existed before. When finished, the various build_*
872 operand vectors will have potential operands. in them. */
875 parse_ssa_operands (tree stmt
)
879 code
= TREE_CODE (stmt
);
883 /* First get operands from the RHS. For the LHS, we use a V_MAY_DEF if
884 either only part of LHS is modified or if the RHS might throw,
885 otherwise, use V_MUST_DEF.
887 ??? If it might throw, we should represent somehow that it is killed
888 on the fallthrough path. */
890 tree lhs
= TREE_OPERAND (stmt
, 0);
891 int lhs_flags
= opf_is_def
;
893 get_expr_operands (stmt
, &TREE_OPERAND (stmt
, 1), opf_none
);
895 /* If the LHS is a VIEW_CONVERT_EXPR, it isn't changing whether
896 or not the entire LHS is modified; that depends on what's
897 inside the VIEW_CONVERT_EXPR. */
898 if (TREE_CODE (lhs
) == VIEW_CONVERT_EXPR
)
899 lhs
= TREE_OPERAND (lhs
, 0);
901 if (TREE_CODE (lhs
) != ARRAY_REF
&& TREE_CODE (lhs
) != ARRAY_RANGE_REF
902 && TREE_CODE (lhs
) != BIT_FIELD_REF
903 && TREE_CODE (lhs
) != REALPART_EXPR
904 && TREE_CODE (lhs
) != IMAGPART_EXPR
)
905 lhs_flags
|= opf_kill_def
;
907 get_expr_operands (stmt
, &TREE_OPERAND (stmt
, 0), lhs_flags
);
912 get_expr_operands (stmt
, &COND_EXPR_COND (stmt
), opf_none
);
916 get_expr_operands (stmt
, &SWITCH_COND (stmt
), opf_none
);
920 get_asm_expr_operands (stmt
);
924 get_expr_operands (stmt
, &TREE_OPERAND (stmt
, 0), opf_none
);
928 get_expr_operands (stmt
, &GOTO_DESTINATION (stmt
), opf_none
);
932 get_expr_operands (stmt
, &LABEL_EXPR_LABEL (stmt
), opf_none
);
935 /* These nodes contain no variable references. */
937 case CASE_LABEL_EXPR
:
939 case TRY_FINALLY_EXPR
:
946 /* Notice that if get_expr_operands tries to use &STMT as the operand
947 pointer (which may only happen for USE operands), we will fail in
948 append_use. This default will handle statements like empty
949 statements, or CALL_EXPRs that may appear on the RHS of a statement
950 or as statements themselves. */
951 get_expr_operands (stmt
, &stmt
, opf_none
);
956 /* Create an operands cache for STMT, returning it in NEW_OPS. OLD_OPS are the
957 original operands, and if ANN is non-null, appropriate stmt flags are set
958 in the stmt's annotation. If ANN is NULL, this is not considered a "real"
959 stmt, and none of the operands will be entered into their respective
960 immediate uses tables. This is to allow stmts to be processed when they
961 are not actually in the CFG.
963 Note that some fields in old_ops may change to NULL, although none of the
964 memory they originally pointed to will be destroyed. It is appropriate
965 to call free_stmt_operands() on the value returned in old_ops.
967 The rationale for this: Certain optimizations wish to examine the difference
968 between new_ops and old_ops after processing. If a set of operands don't
969 change, new_ops will simply assume the pointer in old_ops, and the old_ops
970 pointer will be set to NULL, indicating no memory needs to be cleared.
971 Usage might appear something like:
973 old_ops_copy = old_ops = stmt_ann(stmt)->operands;
974 build_ssa_operands (stmt, NULL, &old_ops, &new_ops);
975 <* compare old_ops_copy and new_ops *>
976 free_ssa_operands (old_ops); */
979 build_ssa_operands (tree stmt
)
981 stmt_ann_t ann
= get_stmt_ann (stmt
);
983 /* Initially assume that the statement has no volatile operands, nor
984 makes aliased loads or stores. */
987 ann
->has_volatile_ops
= false;
988 ann
->makes_aliased_stores
= false;
989 ann
->makes_aliased_loads
= false;
992 start_ssa_stmt_operands ();
994 parse_ssa_operands (stmt
);
996 finalize_ssa_stmt_operands (stmt
);
1000 /* Free any operands vectors in OPS. */
1003 free_ssa_operands (stmt_operands_p ops
)
1005 ops
->def_ops
= NULL
;
1006 ops
->use_ops
= NULL
;
1007 ops
->maydef_ops
= NULL
;
1008 ops
->mustdef_ops
= NULL
;
1009 ops
->vuse_ops
= NULL
;
1010 while (ops
->memory
.next
!= NULL
)
1012 operand_memory_p tmp
= ops
->memory
.next
;
1013 ops
->memory
.next
= tmp
->next
;
1020 /* Get the operands of statement STMT. Note that repeated calls to
1021 get_stmt_operands for the same statement will do nothing until the
1022 statement is marked modified by a call to mark_stmt_modified(). */
1025 update_stmt_operands (tree stmt
)
1027 stmt_ann_t ann
= get_stmt_ann (stmt
);
1028 /* If get_stmt_operands is called before SSA is initialized, dont
1030 if (!ssa_operands_active ())
1032 /* The optimizers cannot handle statements that are nothing but a
1033 _DECL. This indicates a bug in the gimplifier. */
1034 gcc_assert (!SSA_VAR_P (stmt
));
1036 gcc_assert (ann
->modified
);
1038 timevar_push (TV_TREE_OPS
);
1040 build_ssa_operands (stmt
);
1042 /* Clear the modified bit for STMT. Subsequent calls to
1043 get_stmt_operands for this statement will do nothing until the
1044 statement is marked modified by a call to mark_stmt_modified(). */
1047 timevar_pop (TV_TREE_OPS
);
1051 /* Copies virtual operands from SRC to DST. */
1054 copy_virtual_operands (tree dest
, tree src
)
1057 ssa_op_iter iter
, old_iter
;
1058 use_operand_p use_p
, u2
;
1059 def_operand_p def_p
, d2
;
1061 build_ssa_operands (dest
);
1063 /* Copy all the virtual fields. */
1064 FOR_EACH_SSA_TREE_OPERAND (t
, src
, iter
, SSA_OP_VUSE
)
1066 FOR_EACH_SSA_TREE_OPERAND (t
, src
, iter
, SSA_OP_VMAYDEF
)
1067 append_v_may_def (t
);
1068 FOR_EACH_SSA_TREE_OPERAND (t
, src
, iter
, SSA_OP_VMUSTDEF
)
1069 append_v_must_def (t
);
1071 if (opbuild_num_elems (&build_vuses
) == 0
1072 && opbuild_num_elems (&build_v_may_defs
) == 0
1073 && opbuild_num_elems (&build_v_must_defs
) == 0)
1076 /* Now commit the virtual operands to this stmt. */
1077 finalize_ssa_v_must_defs (dest
);
1078 finalize_ssa_v_may_defs (dest
);
1079 finalize_ssa_vuses (dest
);
1081 /* Finally, set the field to the same values as then originals. */
1084 t
= op_iter_init_tree (&old_iter
, src
, SSA_OP_VUSE
);
1085 FOR_EACH_SSA_USE_OPERAND (use_p
, dest
, iter
, SSA_OP_VUSE
)
1087 gcc_assert (!op_iter_done (&old_iter
));
1089 t
= op_iter_next_tree (&old_iter
);
1091 gcc_assert (op_iter_done (&old_iter
));
1093 op_iter_init_maydef (&old_iter
, src
, &u2
, &d2
);
1094 FOR_EACH_SSA_MAYDEF_OPERAND (def_p
, use_p
, dest
, iter
)
1096 gcc_assert (!op_iter_done (&old_iter
));
1097 SET_USE (use_p
, USE_FROM_PTR (u2
));
1098 SET_DEF (def_p
, DEF_FROM_PTR (d2
));
1099 op_iter_next_maymustdef (&u2
, &d2
, &old_iter
);
1101 gcc_assert (op_iter_done (&old_iter
));
1103 op_iter_init_mustdef (&old_iter
, src
, &u2
, &d2
);
1104 FOR_EACH_SSA_MUSTDEF_OPERAND (def_p
, use_p
, dest
, iter
)
1106 gcc_assert (!op_iter_done (&old_iter
));
1107 SET_USE (use_p
, USE_FROM_PTR (u2
));
1108 SET_DEF (def_p
, DEF_FROM_PTR (d2
));
1109 op_iter_next_maymustdef (&u2
, &d2
, &old_iter
);
1111 gcc_assert (op_iter_done (&old_iter
));
1116 /* Specifically for use in DOM's expression analysis. Given a store, we
1117 create an artificial stmt which looks like a load from the store, this can
1118 be used to eliminate redundant loads. OLD_OPS are the operands from the
1119 store stmt, and NEW_STMT is the new load which represents a load of the
1123 create_ssa_artficial_load_stmt (tree new_stmt
, tree old_stmt
)
1128 use_operand_p use_p
;
1131 ann
= get_stmt_ann (new_stmt
);
1133 /* process the stmt looking for operands. */
1134 start_ssa_stmt_operands ();
1135 parse_ssa_operands (new_stmt
);
1137 for (x
= 0; x
< opbuild_num_elems (&build_vuses
); x
++)
1139 tree t
= opbuild_elem_virtual (&build_vuses
, x
);
1140 if (TREE_CODE (t
) != SSA_NAME
)
1142 var_ann_t ann
= var_ann (t
);
1143 ann
->in_vuse_list
= 0;
1147 for (x
= 0; x
< opbuild_num_elems (&build_v_may_defs
); x
++)
1149 tree t
= opbuild_elem_virtual (&build_v_may_defs
, x
);
1150 if (TREE_CODE (t
) != SSA_NAME
)
1152 var_ann_t ann
= var_ann (t
);
1153 ann
->in_v_may_def_list
= 0;
1156 /* Remove any virtual operands that were found. */
1157 opbuild_clear (&build_v_may_defs
);
1158 opbuild_clear (&build_v_must_defs
);
1159 opbuild_clear (&build_vuses
);
1161 /* For each VDEF on the original statement, we want to create a
1162 VUSE of the V_MAY_DEF result or V_MUST_DEF op on the new
1164 FOR_EACH_SSA_TREE_OPERAND (op
, old_stmt
, iter
,
1165 (SSA_OP_VMAYDEF
| SSA_OP_VMUSTDEF
))
1168 /* Now build the operands for this new stmt. */
1169 finalize_ssa_stmt_operands (new_stmt
);
1171 /* All uses in this fake stmt must not be in the immediate use lists. */
1172 FOR_EACH_SSA_USE_OPERAND (use_p
, new_stmt
, iter
, SSA_OP_ALL_USES
)
1173 delink_imm_use (use_p
);
1177 swap_tree_operands (tree stmt
, tree
*exp0
, tree
*exp1
)
1183 /* If the operand cache is active, attempt to preserve the relative positions
1184 of these two operands in their respective immediate use lists. */
1185 if (ssa_operands_active () && op0
!= op1
)
1187 use_optype_p use0
, use1
, ptr
;
1189 /* Find the 2 operands in the cache, if they are there. */
1190 for (ptr
= USE_OPS (stmt
); ptr
; ptr
= ptr
->next
)
1191 if (USE_OP_PTR (ptr
)->use
== exp0
)
1196 for (ptr
= USE_OPS (stmt
); ptr
; ptr
= ptr
->next
)
1197 if (USE_OP_PTR (ptr
)->use
== exp1
)
1202 /* If both uses don't have operand entries, there isn't much we can do
1203 at this point. Presumably we dont need to worry about it. */
1206 tree
*tmp
= USE_OP_PTR (use1
)->use
;
1207 USE_OP_PTR (use1
)->use
= USE_OP_PTR (use0
)->use
;
1208 USE_OP_PTR (use0
)->use
= tmp
;
1212 /* Now swap the data. */
1218 /* Recursively scan the expression pointed by EXPR_P in statement referred to
1219 by INFO. FLAGS is one of the OPF_* constants modifying how to interpret the
1223 get_expr_operands (tree stmt
, tree
*expr_p
, int flags
)
1225 enum tree_code code
;
1226 enum tree_code_class
class;
1227 tree expr
= *expr_p
;
1228 stmt_ann_t s_ann
= stmt_ann (stmt
);
1233 code
= TREE_CODE (expr
);
1234 class = TREE_CODE_CLASS (code
);
1239 /* We could have the address of a component, array member,
1240 etc which has interesting variable references. */
1241 /* Taking the address of a variable does not represent a
1242 reference to it, but the fact that the stmt takes its address will be
1243 of interest to some passes (e.g. alias resolution). */
1244 add_stmt_operand (expr_p
, s_ann
, 0);
1246 /* If the address is invariant, there may be no interesting variable
1247 references inside. */
1248 if (is_gimple_min_invariant (expr
))
1251 /* There should be no VUSEs created, since the referenced objects are
1252 not really accessed. The only operands that we should find here
1253 are ARRAY_REF indices which will always be real operands (GIMPLE
1254 does not allow non-registers as array indices). */
1255 flags
|= opf_no_vops
;
1257 get_expr_operands (stmt
, &TREE_OPERAND (expr
, 0), flags
);
1268 /* Add the subvars for a variable if it has subvars, to DEFS or USES.
1269 Otherwise, add the variable itself.
1270 Whether it goes to USES or DEFS depends on the operand flags. */
1271 if (var_can_have_subvars (expr
)
1272 && (svars
= get_subvars_for_var (expr
)))
1275 for (sv
= svars
; sv
; sv
= sv
->next
)
1276 add_stmt_operand (&sv
->var
, s_ann
, flags
);
1280 add_stmt_operand (expr_p
, s_ann
, flags
);
1284 case MISALIGNED_INDIRECT_REF
:
1285 get_expr_operands (stmt
, &TREE_OPERAND (expr
, 1), flags
);
1288 case ALIGN_INDIRECT_REF
:
1290 get_indirect_ref_operands (stmt
, expr
, flags
);
1293 case TARGET_MEM_REF
:
1294 get_tmr_operands (stmt
, expr
, flags
);
1298 case ARRAY_RANGE_REF
:
1299 /* Treat array references as references to the virtual variable
1300 representing the array. The virtual variable for an ARRAY_REF
1301 is the VAR_DECL for the array. */
1303 /* Add the virtual variable for the ARRAY_REF to VDEFS or VUSES
1304 according to the value of IS_DEF. Recurse if the LHS of the
1305 ARRAY_REF node is not a regular variable. */
1306 if (SSA_VAR_P (TREE_OPERAND (expr
, 0)))
1307 add_stmt_operand (expr_p
, s_ann
, flags
);
1309 get_expr_operands (stmt
, &TREE_OPERAND (expr
, 0), flags
);
1311 get_expr_operands (stmt
, &TREE_OPERAND (expr
, 1), opf_none
);
1312 get_expr_operands (stmt
, &TREE_OPERAND (expr
, 2), opf_none
);
1313 get_expr_operands (stmt
, &TREE_OPERAND (expr
, 3), opf_none
);
1321 HOST_WIDE_INT offset
, size
;
1322 /* This component ref becomes an access to all of the subvariables
1323 it can touch, if we can determine that, but *NOT* the real one.
1324 If we can't determine which fields we could touch, the recursion
1325 will eventually get to a variable and add *all* of its subvars, or
1326 whatever is the minimum correct subset. */
1328 ref
= okay_component_ref_for_subvars (expr
, &offset
, &size
);
1331 subvar_t svars
= get_subvars_for_var (ref
);
1333 for (sv
= svars
; sv
; sv
= sv
->next
)
1336 if (overlap_subvar (offset
, size
, sv
, &exact
))
1339 flags
&= ~opf_kill_def
;
1340 add_stmt_operand (&sv
->var
, s_ann
, flags
);
1345 get_expr_operands (stmt
, &TREE_OPERAND (expr
, 0),
1346 flags
& ~opf_kill_def
);
1348 if (code
== COMPONENT_REF
)
1350 if (s_ann
&& TREE_THIS_VOLATILE (TREE_OPERAND (expr
, 1)))
1351 s_ann
->has_volatile_ops
= true;
1352 get_expr_operands (stmt
, &TREE_OPERAND (expr
, 2), opf_none
);
1356 case WITH_SIZE_EXPR
:
1357 /* WITH_SIZE_EXPR is a pass-through reference to its first argument,
1358 and an rvalue reference to its second argument. */
1359 get_expr_operands (stmt
, &TREE_OPERAND (expr
, 1), opf_none
);
1360 get_expr_operands (stmt
, &TREE_OPERAND (expr
, 0), flags
);
1364 get_call_expr_operands (stmt
, expr
);
1369 get_expr_operands (stmt
, &TREE_OPERAND (expr
, 0), opf_none
);
1370 get_expr_operands (stmt
, &TREE_OPERAND (expr
, 1), opf_none
);
1371 get_expr_operands (stmt
, &TREE_OPERAND (expr
, 2), opf_none
);
1379 get_expr_operands (stmt
, &TREE_OPERAND (expr
, 1), opf_none
);
1381 op
= TREE_OPERAND (expr
, 0);
1382 if (TREE_CODE (op
) == WITH_SIZE_EXPR
)
1383 op
= TREE_OPERAND (expr
, 0);
1384 if (TREE_CODE (op
) == ARRAY_REF
1385 || TREE_CODE (op
) == ARRAY_RANGE_REF
1386 || TREE_CODE (op
) == REALPART_EXPR
1387 || TREE_CODE (op
) == IMAGPART_EXPR
)
1388 subflags
= opf_is_def
;
1390 subflags
= opf_is_def
| opf_kill_def
;
1392 get_expr_operands (stmt
, &TREE_OPERAND (expr
, 0), subflags
);
1398 /* General aggregate CONSTRUCTORs have been decomposed, but they
1399 are still in use as the COMPLEX_EXPR equivalent for vectors. */
1402 for (t
= TREE_OPERAND (expr
, 0); t
; t
= TREE_CHAIN (t
))
1403 get_expr_operands (stmt
, &TREE_VALUE (t
), opf_none
);
1408 case TRUTH_NOT_EXPR
:
1410 case VIEW_CONVERT_EXPR
:
1412 get_expr_operands (stmt
, &TREE_OPERAND (expr
, 0), flags
);
1415 case TRUTH_AND_EXPR
:
1417 case TRUTH_XOR_EXPR
:
1423 tree op0
= TREE_OPERAND (expr
, 0);
1424 tree op1
= TREE_OPERAND (expr
, 1);
1426 /* If it would be profitable to swap the operands, then do so to
1427 canonicalize the statement, enabling better optimization.
1429 By placing canonicalization of such expressions here we
1430 transparently keep statements in canonical form, even
1431 when the statement is modified. */
1432 if (tree_swap_operands_p (op0
, op1
, false))
1434 /* For relationals we need to swap the operands
1435 and change the code. */
1441 TREE_SET_CODE (expr
, swap_tree_comparison (code
));
1442 swap_tree_operands (stmt
,
1443 &TREE_OPERAND (expr
, 0),
1444 &TREE_OPERAND (expr
, 1));
1447 /* For a commutative operator we can just swap the operands. */
1448 else if (commutative_tree_code (code
))
1450 swap_tree_operands (stmt
,
1451 &TREE_OPERAND (expr
, 0),
1452 &TREE_OPERAND (expr
, 1));
1456 get_expr_operands (stmt
, &TREE_OPERAND (expr
, 0), flags
);
1457 get_expr_operands (stmt
, &TREE_OPERAND (expr
, 1), flags
);
1461 case REALIGN_LOAD_EXPR
:
1463 get_expr_operands (stmt
, &TREE_OPERAND (expr
, 0), flags
);
1464 get_expr_operands (stmt
, &TREE_OPERAND (expr
, 1), flags
);
1465 get_expr_operands (stmt
, &TREE_OPERAND (expr
, 2), flags
);
1474 /* Expressions that make no memory references. */
1478 if (class == tcc_unary
)
1480 if (class == tcc_binary
|| class == tcc_comparison
)
1482 if (class == tcc_constant
|| class == tcc_type
)
1486 /* If we get here, something has gone wrong. */
1487 #ifdef ENABLE_CHECKING
1488 fprintf (stderr
, "unhandled expression in get_expr_operands():\n");
1490 fputs ("\n", stderr
);
1491 internal_error ("internal error");
1497 /* Scan operands in the ASM_EXPR stmt referred to in INFO. */
1500 get_asm_expr_operands (tree stmt
)
1502 stmt_ann_t s_ann
= stmt_ann (stmt
);
1503 int noutputs
= list_length (ASM_OUTPUTS (stmt
));
1504 const char **oconstraints
1505 = (const char **) alloca ((noutputs
) * sizeof (const char *));
1508 const char *constraint
;
1509 bool allows_mem
, allows_reg
, is_inout
;
1511 for (i
=0, link
= ASM_OUTPUTS (stmt
); link
; ++i
, link
= TREE_CHAIN (link
))
1513 oconstraints
[i
] = constraint
1514 = TREE_STRING_POINTER (TREE_VALUE (TREE_PURPOSE (link
)));
1515 parse_output_constraint (&constraint
, i
, 0, 0,
1516 &allows_mem
, &allows_reg
, &is_inout
);
1518 /* This should have been split in gimplify_asm_expr. */
1519 gcc_assert (!allows_reg
|| !is_inout
);
1521 /* Memory operands are addressable. Note that STMT needs the
1522 address of this operand. */
1523 if (!allows_reg
&& allows_mem
)
1525 tree t
= get_base_address (TREE_VALUE (link
));
1526 if (t
&& DECL_P (t
))
1527 note_addressable (t
, s_ann
);
1530 get_expr_operands (stmt
, &TREE_VALUE (link
), opf_is_def
);
1533 for (link
= ASM_INPUTS (stmt
); link
; link
= TREE_CHAIN (link
))
1536 = TREE_STRING_POINTER (TREE_VALUE (TREE_PURPOSE (link
)));
1537 parse_input_constraint (&constraint
, 0, 0, noutputs
, 0,
1538 oconstraints
, &allows_mem
, &allows_reg
);
1540 /* Memory operands are addressable. Note that STMT needs the
1541 address of this operand. */
1542 if (!allows_reg
&& allows_mem
)
1544 tree t
= get_base_address (TREE_VALUE (link
));
1545 if (t
&& DECL_P (t
))
1546 note_addressable (t
, s_ann
);
1549 get_expr_operands (stmt
, &TREE_VALUE (link
), 0);
1553 /* Clobber memory for asm ("" : : : "memory"); */
1554 for (link
= ASM_CLOBBERS (stmt
); link
; link
= TREE_CHAIN (link
))
1555 if (strcmp (TREE_STRING_POINTER (TREE_VALUE (link
)), "memory") == 0)
1560 /* Clobber all call-clobbered variables (or .GLOBAL_VAR if we
1561 decided to group them). */
1563 add_stmt_operand (&global_var
, s_ann
, opf_is_def
);
1565 EXECUTE_IF_SET_IN_BITMAP (call_clobbered_vars
, 0, i
, bi
)
1567 tree var
= referenced_var (i
);
1568 add_stmt_operand (&var
, s_ann
, opf_is_def
| opf_non_specific
);
1571 /* Now clobber all addressables. */
1572 EXECUTE_IF_SET_IN_BITMAP (addressable_vars
, 0, i
, bi
)
1574 tree var
= referenced_var (i
);
1576 /* Subvars are explicitly represented in this list, so
1577 we don't need the original to be added to the clobber
1578 ops, but the original *will* be in this list because
1579 we keep the addressability of the original
1580 variable up-to-date so we don't screw up the rest of
1582 if (var_can_have_subvars (var
)
1583 && get_subvars_for_var (var
) != NULL
)
1586 add_stmt_operand (&var
, s_ann
, opf_is_def
| opf_non_specific
);
1593 /* A subroutine of get_expr_operands to handle INDIRECT_REF,
1594 ALIGN_INDIRECT_REF and MISALIGNED_INDIRECT_REF. */
1597 get_indirect_ref_operands (tree stmt
, tree expr
, int flags
)
1599 tree
*pptr
= &TREE_OPERAND (expr
, 0);
1601 stmt_ann_t s_ann
= stmt_ann (stmt
);
1603 /* Stores into INDIRECT_REF operands are never killing definitions. */
1604 flags
&= ~opf_kill_def
;
1606 if (SSA_VAR_P (ptr
))
1608 struct ptr_info_def
*pi
= NULL
;
1610 /* If PTR has flow-sensitive points-to information, use it. */
1611 if (TREE_CODE (ptr
) == SSA_NAME
1612 && (pi
= SSA_NAME_PTR_INFO (ptr
)) != NULL
1613 && pi
->name_mem_tag
)
1615 /* PTR has its own memory tag. Use it. */
1616 add_stmt_operand (&pi
->name_mem_tag
, s_ann
, flags
);
1620 /* If PTR is not an SSA_NAME or it doesn't have a name
1621 tag, use its type memory tag. */
1624 /* If we are emitting debugging dumps, display a warning if
1625 PTR is an SSA_NAME with no flow-sensitive alias
1626 information. That means that we may need to compute
1629 && TREE_CODE (ptr
) == SSA_NAME
1633 "NOTE: no flow-sensitive alias info for ");
1634 print_generic_expr (dump_file
, ptr
, dump_flags
);
1635 fprintf (dump_file
, " in ");
1636 print_generic_stmt (dump_file
, stmt
, dump_flags
);
1639 if (TREE_CODE (ptr
) == SSA_NAME
)
1640 ptr
= SSA_NAME_VAR (ptr
);
1641 v_ann
= var_ann (ptr
);
1642 if (v_ann
->type_mem_tag
)
1643 add_stmt_operand (&v_ann
->type_mem_tag
, s_ann
, flags
);
1647 /* If a constant is used as a pointer, we can't generate a real
1648 operand for it but we mark the statement volatile to prevent
1649 optimizations from messing things up. */
1650 else if (TREE_CODE (ptr
) == INTEGER_CST
)
1653 s_ann
->has_volatile_ops
= true;
1657 /* Everything else *should* have been folded elsewhere, but users
1658 are smarter than we in finding ways to write invalid code. We
1659 cannot just assert here. If we were absolutely certain that we
1660 do handle all valid cases, then we could just do nothing here.
1661 That seems optimistic, so attempt to do something logical... */
1662 else if ((TREE_CODE (ptr
) == PLUS_EXPR
|| TREE_CODE (ptr
) == MINUS_EXPR
)
1663 && TREE_CODE (TREE_OPERAND (ptr
, 0)) == ADDR_EXPR
1664 && TREE_CODE (TREE_OPERAND (ptr
, 1)) == INTEGER_CST
)
1666 /* Make sure we know the object is addressable. */
1667 pptr
= &TREE_OPERAND (ptr
, 0);
1668 add_stmt_operand (pptr
, s_ann
, 0);
1670 /* Mark the object itself with a VUSE. */
1671 pptr
= &TREE_OPERAND (*pptr
, 0);
1672 get_expr_operands (stmt
, pptr
, flags
);
1676 /* Ok, this isn't even is_gimple_min_invariant. Something's broke. */
1680 /* Add a USE operand for the base pointer. */
1681 get_expr_operands (stmt
, pptr
, opf_none
);
1684 /* A subroutine of get_expr_operands to handle TARGET_MEM_REF. */
1687 get_tmr_operands (tree stmt
, tree expr
, int flags
)
1689 tree tag
= TMR_TAG (expr
);
1691 /* First record the real operands. */
1692 get_expr_operands (stmt
, &TMR_BASE (expr
), opf_none
);
1693 get_expr_operands (stmt
, &TMR_INDEX (expr
), opf_none
);
1695 /* MEM_REFs should never be killing. */
1696 flags
&= ~opf_kill_def
;
1698 if (TMR_SYMBOL (expr
))
1699 note_addressable (TMR_SYMBOL (expr
), stmt_ann (stmt
));
1702 add_stmt_operand (&tag
, stmt_ann (stmt
), flags
);
1704 /* Something weird, so ensure that we will be careful. */
1705 stmt_ann (stmt
)->has_volatile_ops
= true;
1708 /* A subroutine of get_expr_operands to handle CALL_EXPR. */
1711 get_call_expr_operands (tree stmt
, tree expr
)
1714 int call_flags
= call_expr_flags (expr
);
1716 /* If aliases have been computed already, add V_MAY_DEF or V_USE
1717 operands for all the symbols that have been found to be
1720 Note that if aliases have not been computed, the global effects
1721 of calls will not be included in the SSA web. This is fine
1722 because no optimizer should run before aliases have been
1723 computed. By not bothering with virtual operands for CALL_EXPRs
1724 we avoid adding superfluous virtual operands, which can be a
1725 significant compile time sink (See PR 15855). */
1726 if (aliases_computed_p
1727 && !bitmap_empty_p (call_clobbered_vars
)
1728 && !(call_flags
& ECF_NOVOPS
))
1730 /* A 'pure' or a 'const' function never call-clobbers anything.
1731 A 'noreturn' function might, but since we don't return anyway
1732 there is no point in recording that. */
1733 if (TREE_SIDE_EFFECTS (expr
)
1734 && !(call_flags
& (ECF_PURE
| ECF_CONST
| ECF_NORETURN
)))
1735 add_call_clobber_ops (stmt
);
1736 else if (!(call_flags
& ECF_CONST
))
1737 add_call_read_ops (stmt
);
1740 /* Find uses in the called function. */
1741 get_expr_operands (stmt
, &TREE_OPERAND (expr
, 0), opf_none
);
1743 for (op
= TREE_OPERAND (expr
, 1); op
; op
= TREE_CHAIN (op
))
1744 get_expr_operands (stmt
, &TREE_VALUE (op
), opf_none
);
1746 get_expr_operands (stmt
, &TREE_OPERAND (expr
, 2), opf_none
);
1751 /* Add *VAR_P to the appropriate operand array for INFO. FLAGS is as in
1752 get_expr_operands. If *VAR_P is a GIMPLE register, it will be added to
1753 the statement's real operands, otherwise it is added to virtual
1757 add_stmt_operand (tree
*var_p
, stmt_ann_t s_ann
, int flags
)
1766 /* If the operand is an ADDR_EXPR, add its operand to the list of
1767 variables that have had their address taken in this statement. */
1768 if (TREE_CODE (var
) == ADDR_EXPR
)
1770 note_addressable (TREE_OPERAND (var
, 0), s_ann
);
1774 /* If the original variable is not a scalar, it will be added to the list
1775 of virtual operands. In that case, use its base symbol as the virtual
1776 variable representing it. */
1777 is_real_op
= is_gimple_reg (var
);
1778 if (!is_real_op
&& !DECL_P (var
))
1779 var
= get_virtual_var (var
);
1781 /* If VAR is not a variable that we care to optimize, do nothing. */
1782 if (var
== NULL_TREE
|| !SSA_VAR_P (var
))
1785 sym
= (TREE_CODE (var
) == SSA_NAME
? SSA_NAME_VAR (var
) : var
);
1786 v_ann
= var_ann (sym
);
1788 /* Mark statements with volatile operands. Optimizers should back
1789 off from statements having volatile operands. */
1790 if (TREE_THIS_VOLATILE (sym
) && s_ann
)
1791 s_ann
->has_volatile_ops
= true;
1793 /* If the variable cannot be modified and this is a V_MAY_DEF change
1794 it into a VUSE. This happens when read-only variables are marked
1795 call-clobbered and/or aliased to writable variables. So we only
1796 check that this only happens on non-specific stores.
1798 Note that if this is a specific store, i.e. associated with a
1799 modify_expr, then we can't suppress the V_DEF, lest we run into
1800 validation problems.
1802 This can happen when programs cast away const, leaving us with a
1803 store to read-only memory. If the statement is actually executed
1804 at runtime, then the program is ill formed. If the statement is
1805 not executed then all is well. At the very least, we cannot ICE. */
1806 if ((flags
& opf_non_specific
) && unmodifiable_var_p (var
))
1808 gcc_assert (!is_real_op
);
1809 flags
&= ~(opf_is_def
| opf_kill_def
);
1814 /* The variable is a GIMPLE register. Add it to real operands. */
1815 if (flags
& opf_is_def
)
1822 varray_type aliases
;
1824 /* The variable is not a GIMPLE register. Add it (or its aliases) to
1825 virtual operands, unless the caller has specifically requested
1826 not to add virtual operands (used when adding operands inside an
1827 ADDR_EXPR expression). */
1828 if (flags
& opf_no_vops
)
1831 aliases
= v_ann
->may_aliases
;
1833 if (aliases
== NULL
)
1835 /* The variable is not aliased or it is an alias tag. */
1836 if (flags
& opf_is_def
)
1838 if (flags
& opf_kill_def
)
1840 /* Only regular variables or struct fields may get a
1841 V_MUST_DEF operand. */
1842 gcc_assert (v_ann
->mem_tag_kind
== NOT_A_TAG
1843 || v_ann
->mem_tag_kind
== STRUCT_FIELD
);
1844 /* V_MUST_DEF for non-aliased, non-GIMPLE register
1845 variable definitions. */
1846 append_v_must_def (var
);
1850 /* Add a V_MAY_DEF for call-clobbered variables and
1852 append_v_may_def (var
);
1858 if (s_ann
&& v_ann
->is_alias_tag
)
1859 s_ann
->makes_aliased_loads
= 1;
1866 /* The variable is aliased. Add its aliases to the virtual
1868 gcc_assert (VARRAY_ACTIVE_SIZE (aliases
) != 0);
1870 if (flags
& opf_is_def
)
1872 bool added_may_defs_p
= false;
1874 /* If the variable is also an alias tag, add a virtual
1875 operand for it, otherwise we will miss representing
1876 references to the members of the variable's alias set.
1877 This fixes the bug in gcc.c-torture/execute/20020503-1.c. */
1878 if (v_ann
->is_alias_tag
)
1880 added_may_defs_p
= true;
1881 append_v_may_def (var
);
1884 for (i
= 0; i
< VARRAY_ACTIVE_SIZE (aliases
); i
++)
1886 /* While VAR may be modifiable, some of its aliases
1887 may not be. If that's the case, we don't really
1888 need to add them a V_MAY_DEF for them. */
1889 tree alias
= VARRAY_TREE (aliases
, i
);
1891 if (unmodifiable_var_p (alias
))
1892 append_vuse (alias
);
1895 append_v_may_def (alias
);
1896 added_may_defs_p
= true;
1900 if (s_ann
&& added_may_defs_p
)
1901 s_ann
->makes_aliased_stores
= 1;
1905 /* Similarly, append a virtual uses for VAR itself, when
1906 it is an alias tag. */
1907 if (v_ann
->is_alias_tag
)
1910 for (i
= 0; i
< VARRAY_ACTIVE_SIZE (aliases
); i
++)
1911 append_vuse (VARRAY_TREE (aliases
, i
));
1914 s_ann
->makes_aliased_loads
= 1;
1921 /* Record that VAR had its address taken in the statement with annotations
1925 note_addressable (tree var
, stmt_ann_t s_ann
)
1932 /* Note that it is *NOT OKAY* to use the target of a COMPONENT_REF
1933 as the only thing we take the address of.
1934 See PR 21407 and the ensuing mailing list discussion. */
1936 var
= get_base_address (var
);
1937 if (var
&& SSA_VAR_P (var
))
1939 if (s_ann
->addresses_taken
== NULL
)
1940 s_ann
->addresses_taken
= BITMAP_GGC_ALLOC ();
1943 if (var_can_have_subvars (var
)
1944 && (svars
= get_subvars_for_var (var
)))
1947 for (sv
= svars
; sv
; sv
= sv
->next
)
1948 bitmap_set_bit (s_ann
->addresses_taken
, var_ann (sv
->var
)->uid
);
1951 bitmap_set_bit (s_ann
->addresses_taken
, var_ann (var
)->uid
);
1955 /* Add clobbering definitions for .GLOBAL_VAR or for each of the call
1956 clobbered variables in the function. */
1959 add_call_clobber_ops (tree stmt
)
1965 stmt_ann_t s_ann
= stmt_ann (stmt
);
1966 struct stmt_ann_d empty_ann
;
1968 /* Functions that are not const, pure or never return may clobber
1969 call-clobbered variables. */
1971 s_ann
->makes_clobbering_call
= true;
1973 /* If we created .GLOBAL_VAR earlier, just use it. See compute_may_aliases
1974 for the heuristic used to decide whether to create .GLOBAL_VAR or not. */
1977 add_stmt_operand (&global_var
, s_ann
, opf_is_def
);
1981 /* If cache is valid, copy the elements into the build vectors. */
1982 if (ssa_call_clobbered_cache_valid
)
1984 /* Process the caches in reverse order so we are always inserting at
1985 the head of the list. */
1986 for (i
= VEC_length (tree
, clobbered_vuses
) - 1; i
>=0; i
--)
1988 t
= VEC_index (tree
, clobbered_vuses
, i
);
1989 gcc_assert (TREE_CODE (t
) != SSA_NAME
);
1990 var_ann (t
)->in_vuse_list
= 1;
1991 opbuild_append_virtual (&build_vuses
, t
);
1993 for (i
= VEC_length (tree
, clobbered_v_may_defs
) - 1; i
>= 0; i
--)
1995 t
= VEC_index (tree
, clobbered_v_may_defs
, i
);
1996 gcc_assert (TREE_CODE (t
) != SSA_NAME
);
1997 var_ann (t
)->in_v_may_def_list
= 1;
1998 opbuild_append_virtual (&build_v_may_defs
, t
);
2002 s_ann
->makes_aliased_loads
= clobbered_aliased_loads
;
2003 s_ann
->makes_aliased_stores
= clobbered_aliased_stores
;
2008 memset (&empty_ann
, 0, sizeof (struct stmt_ann_d
));
2010 /* Add a V_MAY_DEF operand for every call clobbered variable. */
2011 EXECUTE_IF_SET_IN_BITMAP (call_clobbered_vars
, 0, u
, bi
)
2013 tree var
= referenced_var (u
);
2014 if (unmodifiable_var_p (var
))
2015 add_stmt_operand (&var
, &empty_ann
, opf_none
);
2017 add_stmt_operand (&var
, &empty_ann
, opf_is_def
| opf_non_specific
);
2020 clobbered_aliased_loads
= empty_ann
.makes_aliased_loads
;
2021 clobbered_aliased_stores
= empty_ann
.makes_aliased_stores
;
2023 /* Set the flags for a stmt's annotation. */
2026 s_ann
->makes_aliased_loads
= empty_ann
.makes_aliased_loads
;
2027 s_ann
->makes_aliased_stores
= empty_ann
.makes_aliased_stores
;
2030 /* Prepare empty cache vectors. */
2031 VEC_truncate (tree
, clobbered_vuses
, 0);
2032 VEC_truncate (tree
, clobbered_v_may_defs
, 0);
2034 /* Now fill the clobbered cache with the values that have been found. */
2035 for (i
= opbuild_first (&build_vuses
);
2037 i
= opbuild_next (&build_vuses
, i
))
2038 VEC_safe_push (tree
, heap
, clobbered_vuses
,
2039 opbuild_elem_virtual (&build_vuses
, i
));
2041 gcc_assert (opbuild_num_elems (&build_vuses
)
2042 == VEC_length (tree
, clobbered_vuses
));
2044 for (i
= opbuild_first (&build_v_may_defs
);
2046 i
= opbuild_next (&build_v_may_defs
, i
))
2047 VEC_safe_push (tree
, heap
, clobbered_v_may_defs
,
2048 opbuild_elem_virtual (&build_v_may_defs
, i
));
2050 gcc_assert (opbuild_num_elems (&build_v_may_defs
)
2051 == VEC_length (tree
, clobbered_v_may_defs
));
2053 ssa_call_clobbered_cache_valid
= true;
2057 /* Add VUSE operands for .GLOBAL_VAR or all call clobbered variables in the
2061 add_call_read_ops (tree stmt
)
2067 stmt_ann_t s_ann
= stmt_ann (stmt
);
2068 struct stmt_ann_d empty_ann
;
2070 /* if the function is not pure, it may reference memory. Add
2071 a VUSE for .GLOBAL_VAR if it has been created. See add_referenced_var
2072 for the heuristic used to decide whether to create .GLOBAL_VAR. */
2075 add_stmt_operand (&global_var
, s_ann
, opf_none
);
2079 /* If cache is valid, copy the elements into the build vector. */
2080 if (ssa_ro_call_cache_valid
)
2082 for (i
= VEC_length (tree
, ro_call_vuses
) - 1; i
>=0 ; i
--)
2084 /* Process the caches in reverse order so we are always inserting at
2085 the head of the list. */
2086 t
= VEC_index (tree
, ro_call_vuses
, i
);
2087 gcc_assert (TREE_CODE (t
) != SSA_NAME
);
2088 var_ann (t
)->in_vuse_list
= 1;
2089 opbuild_append_virtual (&build_vuses
, t
);
2092 s_ann
->makes_aliased_loads
= ro_call_aliased_loads
;
2096 memset (&empty_ann
, 0, sizeof (struct stmt_ann_d
));
2098 /* Add a VUSE for each call-clobbered variable. */
2099 EXECUTE_IF_SET_IN_BITMAP (call_clobbered_vars
, 0, u
, bi
)
2101 tree var
= referenced_var (u
);
2102 add_stmt_operand (&var
, &empty_ann
, opf_none
| opf_non_specific
);
2105 ro_call_aliased_loads
= empty_ann
.makes_aliased_loads
;
2107 s_ann
->makes_aliased_loads
= empty_ann
.makes_aliased_loads
;
2109 /* Prepare empty cache vectors. */
2110 VEC_truncate (tree
, ro_call_vuses
, 0);
2112 /* Now fill the clobbered cache with the values that have been found. */
2113 for (i
= opbuild_first (&build_vuses
);
2115 i
= opbuild_next (&build_vuses
, i
))
2116 VEC_safe_push (tree
, heap
, ro_call_vuses
,
2117 opbuild_elem_virtual (&build_vuses
, i
));
2119 gcc_assert (opbuild_num_elems (&build_vuses
)
2120 == VEC_length (tree
, ro_call_vuses
));
2122 ssa_ro_call_cache_valid
= true;
2126 /* Scan the immediate_use list for VAR making sure its linked properly.
2127 return RTUE iof there is a problem. */
2130 verify_imm_links (FILE *f
, tree var
)
2132 use_operand_p ptr
, prev
, list
;
2135 gcc_assert (TREE_CODE (var
) == SSA_NAME
);
2137 list
= &(SSA_NAME_IMM_USE_NODE (var
));
2138 gcc_assert (list
->use
== NULL
);
2140 if (list
->prev
== NULL
)
2142 gcc_assert (list
->next
== NULL
);
2148 for (ptr
= list
->next
; ptr
!= list
; )
2150 if (prev
!= ptr
->prev
)
2153 if (ptr
->use
== NULL
)
2154 goto error
; /* 2 roots, or SAFE guard node. */
2155 else if (*(ptr
->use
) != var
)
2160 /* Avoid infinite loops. */
2161 if (count
++ > 30000)
2165 /* Verify list in the other direction. */
2167 for (ptr
= list
->prev
; ptr
!= list
; )
2169 if (prev
!= ptr
->next
)
2183 if (ptr
->stmt
&& stmt_modified_p (ptr
->stmt
))
2185 fprintf (f
, " STMT MODIFIED. - <%p> ", (void *)ptr
->stmt
);
2186 print_generic_stmt (f
, ptr
->stmt
, TDF_SLIM
);
2188 fprintf (f
, " IMM ERROR : (use_p : tree - %p:%p)", (void *)ptr
,
2190 print_generic_expr (f
, USE_FROM_PTR (ptr
), TDF_SLIM
);
2196 /* Dump all the immediate uses to FILE. */
2199 dump_immediate_uses_for (FILE *file
, tree var
)
2201 imm_use_iterator iter
;
2202 use_operand_p use_p
;
2204 gcc_assert (var
&& TREE_CODE (var
) == SSA_NAME
);
2206 print_generic_expr (file
, var
, TDF_SLIM
);
2207 fprintf (file
, " : -->");
2208 if (has_zero_uses (var
))
2209 fprintf (file
, " no uses.\n");
2211 if (has_single_use (var
))
2212 fprintf (file
, " single use.\n");
2214 fprintf (file
, "%d uses.\n", num_imm_uses (var
));
2216 FOR_EACH_IMM_USE_FAST (use_p
, iter
, var
)
2218 if (!is_gimple_reg (USE_FROM_PTR (use_p
)))
2219 print_generic_stmt (file
, USE_STMT (use_p
), TDF_VOPS
);
2221 print_generic_stmt (file
, USE_STMT (use_p
), TDF_SLIM
);
2223 fprintf(file
, "\n");
2226 /* Dump all the immediate uses to FILE. */
2229 dump_immediate_uses (FILE *file
)
2234 fprintf (file
, "Immediate_uses: \n\n");
2235 for (x
= 1; x
< num_ssa_names
; x
++)
2240 dump_immediate_uses_for (file
, var
);
2245 /* Dump def-use edges on stderr. */
2248 debug_immediate_uses (void)
2250 dump_immediate_uses (stderr
);
2253 /* Dump def-use edges on stderr. */
2256 debug_immediate_uses_for (tree var
)
2258 dump_immediate_uses_for (stderr
, var
);
2260 #include "gt-tree-ssa-operands.h"