1 /* SCC value numbering for trees
2 Copyright (C) 2006-2020 Free Software Foundation, Inc.
3 Contributed by Daniel Berlin <dan@dberlin.org>
5 This file is part of GCC.
7 GCC is free software; you can redistribute it and/or modify
8 it under the terms of the GNU General Public License as published by
9 the Free Software Foundation; either version 3, or (at your option)
12 GCC is distributed in the hope that it will be useful,
13 but WITHOUT ANY WARRANTY; without even the implied warranty of
14 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15 GNU General Public License for more details.
17 You should have received a copy of the GNU General Public License
18 along with GCC; see the file COPYING3. If not see
19 <http://www.gnu.org/licenses/>. */
23 #include "coretypes.h"
24 #include "splay-tree.h"
31 #include "insn-config.h"
35 #include "gimple-pretty-print.h"
37 #include "fold-const.h"
38 #include "stor-layout.h"
40 #include "tree-inline.h"
41 #include "internal-fn.h"
42 #include "gimple-fold.h"
56 #include "tree-ssa-propagate.h"
59 #include "gimple-iterator.h"
60 #include "gimple-match.h"
61 #include "stringpool.h"
63 #include "tree-pass.h"
64 #include "statistics.h"
65 #include "langhooks.h"
66 #include "ipa-utils.h"
68 #include "tree-cfgcleanup.h"
69 #include "tree-ssa-loop.h"
70 #include "tree-scalar-evolution.h"
71 #include "tree-ssa-loop-niter.h"
73 #include "tree-ssa-sccvn.h"
75 /* This algorithm is based on the SCC algorithm presented by Keith
76 Cooper and L. Taylor Simpson in "SCC-Based Value numbering"
77 (http://citeseer.ist.psu.edu/41805.html). In
78 straight line code, it is equivalent to a regular hash based value
79 numbering that is performed in reverse postorder.
81 For code with cycles, there are two alternatives, both of which
82 require keeping the hashtables separate from the actual list of
83 value numbers for SSA names.
85 1. Iterate value numbering in an RPO walk of the blocks, removing
86 all the entries from the hashtable after each iteration (but
87 keeping the SSA name->value number mapping between iterations).
88 Iterate until it does not change.
90 2. Perform value numbering as part of an SCC walk on the SSA graph,
91 iterating only the cycles in the SSA graph until they do not change
92 (using a separate, optimistic hashtable for value numbering the SCC
95 The second is not just faster in practice (because most SSA graph
96 cycles do not involve all the variables in the graph), it also has
99 One of these nice properties is that when we pop an SCC off the
100 stack, we are guaranteed to have processed all the operands coming from
101 *outside of that SCC*, so we do not need to do anything special to
102 ensure they have value numbers.
104 Another nice property is that the SCC walk is done as part of a DFS
105 of the SSA graph, which makes it easy to perform combining and
106 simplifying operations at the same time.
108 The code below is deliberately written in a way that makes it easy
109 to separate the SCC walk from the other work it does.
111 In order to propagate constants through the code, we track which
112 expressions contain constants, and use those while folding. In
113 theory, we could also track expressions whose value numbers are
114 replaced, in case we end up folding based on expression
117 In order to value number memory, we assign value numbers to vuses.
118 This enables us to note that, for example, stores to the same
119 address of the same value from the same starting memory states are
123 1. We can iterate only the changing portions of the SCC's, but
124 I have not seen an SCC big enough for this to be a win.
125 2. If you differentiate between phi nodes for loops and phi nodes
126 for if-then-else, you can properly consider phi nodes in different
127 blocks for equivalence.
128 3. We could value number vuses in more cases, particularly, whole
132 /* There's no BB_EXECUTABLE but we can use BB_VISITED. */
133 #define BB_EXECUTABLE BB_VISITED
135 static vn_lookup_kind default_vn_walk_kind
;
137 /* vn_nary_op hashtable helpers. */
139 struct vn_nary_op_hasher
: nofree_ptr_hash
<vn_nary_op_s
>
141 typedef vn_nary_op_s
*compare_type
;
142 static inline hashval_t
hash (const vn_nary_op_s
*);
143 static inline bool equal (const vn_nary_op_s
*, const vn_nary_op_s
*);
146 /* Return the computed hashcode for nary operation P1. */
149 vn_nary_op_hasher::hash (const vn_nary_op_s
*vno1
)
151 return vno1
->hashcode
;
154 /* Compare nary operations P1 and P2 and return true if they are
158 vn_nary_op_hasher::equal (const vn_nary_op_s
*vno1
, const vn_nary_op_s
*vno2
)
160 return vno1
== vno2
|| vn_nary_op_eq (vno1
, vno2
);
163 typedef hash_table
<vn_nary_op_hasher
> vn_nary_op_table_type
;
164 typedef vn_nary_op_table_type::iterator vn_nary_op_iterator_type
;
167 /* vn_phi hashtable helpers. */
170 vn_phi_eq (const_vn_phi_t
const vp1
, const_vn_phi_t
const vp2
);
172 struct vn_phi_hasher
: nofree_ptr_hash
<vn_phi_s
>
174 static inline hashval_t
hash (const vn_phi_s
*);
175 static inline bool equal (const vn_phi_s
*, const vn_phi_s
*);
178 /* Return the computed hashcode for phi operation P1. */
181 vn_phi_hasher::hash (const vn_phi_s
*vp1
)
183 return vp1
->hashcode
;
186 /* Compare two phi entries for equality, ignoring VN_TOP arguments. */
189 vn_phi_hasher::equal (const vn_phi_s
*vp1
, const vn_phi_s
*vp2
)
191 return vp1
== vp2
|| vn_phi_eq (vp1
, vp2
);
194 typedef hash_table
<vn_phi_hasher
> vn_phi_table_type
;
195 typedef vn_phi_table_type::iterator vn_phi_iterator_type
;
198 /* Compare two reference operands P1 and P2 for equality. Return true if
199 they are equal, and false otherwise. */
202 vn_reference_op_eq (const void *p1
, const void *p2
)
204 const_vn_reference_op_t
const vro1
= (const_vn_reference_op_t
) p1
;
205 const_vn_reference_op_t
const vro2
= (const_vn_reference_op_t
) p2
;
207 return (vro1
->opcode
== vro2
->opcode
208 /* We do not care for differences in type qualification. */
209 && (vro1
->type
== vro2
->type
210 || (vro1
->type
&& vro2
->type
211 && types_compatible_p (TYPE_MAIN_VARIANT (vro1
->type
),
212 TYPE_MAIN_VARIANT (vro2
->type
))))
213 && expressions_equal_p (vro1
->op0
, vro2
->op0
)
214 && expressions_equal_p (vro1
->op1
, vro2
->op1
)
215 && expressions_equal_p (vro1
->op2
, vro2
->op2
));
218 /* Free a reference operation structure VP. */
221 free_reference (vn_reference_s
*vr
)
223 vr
->operands
.release ();
227 /* vn_reference hashtable helpers. */
229 struct vn_reference_hasher
: nofree_ptr_hash
<vn_reference_s
>
231 static inline hashval_t
hash (const vn_reference_s
*);
232 static inline bool equal (const vn_reference_s
*, const vn_reference_s
*);
235 /* Return the hashcode for a given reference operation P1. */
238 vn_reference_hasher::hash (const vn_reference_s
*vr1
)
240 return vr1
->hashcode
;
244 vn_reference_hasher::equal (const vn_reference_s
*v
, const vn_reference_s
*c
)
246 return v
== c
|| vn_reference_eq (v
, c
);
249 typedef hash_table
<vn_reference_hasher
> vn_reference_table_type
;
250 typedef vn_reference_table_type::iterator vn_reference_iterator_type
;
253 /* The set of VN hashtables. */
255 typedef struct vn_tables_s
257 vn_nary_op_table_type
*nary
;
258 vn_phi_table_type
*phis
;
259 vn_reference_table_type
*references
;
263 /* vn_constant hashtable helpers. */
265 struct vn_constant_hasher
: free_ptr_hash
<vn_constant_s
>
267 static inline hashval_t
hash (const vn_constant_s
*);
268 static inline bool equal (const vn_constant_s
*, const vn_constant_s
*);
271 /* Hash table hash function for vn_constant_t. */
274 vn_constant_hasher::hash (const vn_constant_s
*vc1
)
276 return vc1
->hashcode
;
279 /* Hash table equality function for vn_constant_t. */
282 vn_constant_hasher::equal (const vn_constant_s
*vc1
, const vn_constant_s
*vc2
)
284 if (vc1
->hashcode
!= vc2
->hashcode
)
287 return vn_constant_eq_with_type (vc1
->constant
, vc2
->constant
);
290 static hash_table
<vn_constant_hasher
> *constant_to_value_id
;
291 static bitmap constant_value_ids
;
294 /* Obstack we allocate the vn-tables elements from. */
295 static obstack vn_tables_obstack
;
296 /* Special obstack we never unwind. */
297 static obstack vn_tables_insert_obstack
;
299 static vn_reference_t last_inserted_ref
;
300 static vn_phi_t last_inserted_phi
;
301 static vn_nary_op_t last_inserted_nary
;
303 /* Valid hashtables storing information we have proven to be
305 static vn_tables_t valid_info
;
308 /* Valueization hook. Valueize NAME if it is an SSA name, otherwise
310 tree (*vn_valueize
) (tree
);
311 tree
vn_valueize_wrapper (tree t
, void* context ATTRIBUTE_UNUSED
)
313 return vn_valueize (t
);
317 /* This represents the top of the VN lattice, which is the universal
322 /* Unique counter for our value ids. */
324 static unsigned int next_value_id
;
327 /* Table of vn_ssa_aux_t's, one per ssa_name. The vn_ssa_aux_t objects
328 are allocated on an obstack for locality reasons, and to free them
329 without looping over the vec. */
331 struct vn_ssa_aux_hasher
: typed_noop_remove
<vn_ssa_aux_t
>
333 typedef vn_ssa_aux_t value_type
;
334 typedef tree compare_type
;
335 static inline hashval_t
hash (const value_type
&);
336 static inline bool equal (const value_type
&, const compare_type
&);
337 static inline void mark_deleted (value_type
&) {}
338 static const bool empty_zero_p
= true;
339 static inline void mark_empty (value_type
&e
) { e
= NULL
; }
340 static inline bool is_deleted (value_type
&) { return false; }
341 static inline bool is_empty (value_type
&e
) { return e
== NULL
; }
345 vn_ssa_aux_hasher::hash (const value_type
&entry
)
347 return SSA_NAME_VERSION (entry
->name
);
351 vn_ssa_aux_hasher::equal (const value_type
&entry
, const compare_type
&name
)
353 return name
== entry
->name
;
356 static hash_table
<vn_ssa_aux_hasher
> *vn_ssa_aux_hash
;
357 typedef hash_table
<vn_ssa_aux_hasher
>::iterator vn_ssa_aux_iterator_type
;
358 static struct obstack vn_ssa_aux_obstack
;
360 static vn_nary_op_t
vn_nary_op_insert_stmt (gimple
*, tree
);
361 static unsigned int vn_nary_length_from_stmt (gimple
*);
362 static vn_nary_op_t
alloc_vn_nary_op_noinit (unsigned int, obstack
*);
363 static vn_nary_op_t
vn_nary_op_insert_into (vn_nary_op_t
,
364 vn_nary_op_table_type
*, bool);
365 static void init_vn_nary_op_from_stmt (vn_nary_op_t
, gimple
*);
366 static void init_vn_nary_op_from_pieces (vn_nary_op_t
, unsigned int,
367 enum tree_code
, tree
, tree
*);
368 static tree
vn_lookup_simplify_result (gimple_match_op
*);
369 static vn_reference_t vn_reference_lookup_or_insert_for_pieces
370 (tree
, alias_set_type
, alias_set_type
, tree
,
371 vec
<vn_reference_op_s
, va_heap
>, tree
);
373 /* Return whether there is value numbering information for a given SSA name. */
376 has_VN_INFO (tree name
)
378 return vn_ssa_aux_hash
->find_with_hash (name
, SSA_NAME_VERSION (name
));
385 = vn_ssa_aux_hash
->find_slot_with_hash (name
, SSA_NAME_VERSION (name
),
390 vn_ssa_aux_t newinfo
= *res
= XOBNEW (&vn_ssa_aux_obstack
, struct vn_ssa_aux
);
391 memset (newinfo
, 0, sizeof (struct vn_ssa_aux
));
392 newinfo
->name
= name
;
393 newinfo
->valnum
= VN_TOP
;
394 /* We are using the visited flag to handle uses with defs not within the
395 region being value-numbered. */
396 newinfo
->visited
= false;
398 /* Given we create the VN_INFOs on-demand now we have to do initialization
399 different than VN_TOP here. */
400 if (SSA_NAME_IS_DEFAULT_DEF (name
))
401 switch (TREE_CODE (SSA_NAME_VAR (name
)))
404 /* All undefined vars are VARYING. */
405 newinfo
->valnum
= name
;
406 newinfo
->visited
= true;
410 /* Parameters are VARYING but we can record a condition
411 if we know it is a non-NULL pointer. */
412 newinfo
->visited
= true;
413 newinfo
->valnum
= name
;
414 if (POINTER_TYPE_P (TREE_TYPE (name
))
415 && nonnull_arg_p (SSA_NAME_VAR (name
)))
419 ops
[1] = build_int_cst (TREE_TYPE (name
), 0);
421 /* Allocate from non-unwinding stack. */
422 nary
= alloc_vn_nary_op_noinit (2, &vn_tables_insert_obstack
);
423 init_vn_nary_op_from_pieces (nary
, 2, NE_EXPR
,
424 boolean_type_node
, ops
);
425 nary
->predicated_values
= 0;
426 nary
->u
.result
= boolean_true_node
;
427 vn_nary_op_insert_into (nary
, valid_info
->nary
, true);
428 gcc_assert (nary
->unwind_to
== NULL
);
429 /* Also do not link it into the undo chain. */
430 last_inserted_nary
= nary
->next
;
431 nary
->next
= (vn_nary_op_t
)(void *)-1;
432 nary
= alloc_vn_nary_op_noinit (2, &vn_tables_insert_obstack
);
433 init_vn_nary_op_from_pieces (nary
, 2, EQ_EXPR
,
434 boolean_type_node
, ops
);
435 nary
->predicated_values
= 0;
436 nary
->u
.result
= boolean_false_node
;
437 vn_nary_op_insert_into (nary
, valid_info
->nary
, true);
438 gcc_assert (nary
->unwind_to
== NULL
);
439 last_inserted_nary
= nary
->next
;
440 nary
->next
= (vn_nary_op_t
)(void *)-1;
441 if (dump_file
&& (dump_flags
& TDF_DETAILS
))
443 fprintf (dump_file
, "Recording ");
444 print_generic_expr (dump_file
, name
, TDF_SLIM
);
445 fprintf (dump_file
, " != 0\n");
451 /* If the result is passed by invisible reference the default
452 def is initialized, otherwise it's uninitialized. Still
453 undefined is varying. */
454 newinfo
->visited
= true;
455 newinfo
->valnum
= name
;
464 /* Return the SSA value of X. */
467 SSA_VAL (tree x
, bool *visited
= NULL
)
469 vn_ssa_aux_t tem
= vn_ssa_aux_hash
->find_with_hash (x
, SSA_NAME_VERSION (x
));
471 *visited
= tem
&& tem
->visited
;
472 return tem
&& tem
->visited
? tem
->valnum
: x
;
475 /* Return the SSA value of the VUSE x, supporting released VDEFs
476 during elimination which will value-number the VDEF to the
477 associated VUSE (but not substitute in the whole lattice). */
480 vuse_ssa_val (tree x
)
488 gcc_assert (x
!= VN_TOP
);
490 while (SSA_NAME_IN_FREE_LIST (x
));
495 /* Similar to the above but used as callback for walk_non_aliases_vuses
496 and thus should stop at unvisited VUSE to not walk across region
500 vuse_valueize (tree vuse
)
505 vuse
= SSA_VAL (vuse
, &visited
);
508 gcc_assert (vuse
!= VN_TOP
);
510 while (SSA_NAME_IN_FREE_LIST (vuse
));
515 /* Return the vn_kind the expression computed by the stmt should be
519 vn_get_stmt_kind (gimple
*stmt
)
521 switch (gimple_code (stmt
))
529 enum tree_code code
= gimple_assign_rhs_code (stmt
);
530 tree rhs1
= gimple_assign_rhs1 (stmt
);
531 switch (get_gimple_rhs_class (code
))
533 case GIMPLE_UNARY_RHS
:
534 case GIMPLE_BINARY_RHS
:
535 case GIMPLE_TERNARY_RHS
:
537 case GIMPLE_SINGLE_RHS
:
538 switch (TREE_CODE_CLASS (code
))
541 /* VOP-less references can go through unary case. */
542 if ((code
== REALPART_EXPR
543 || code
== IMAGPART_EXPR
544 || code
== VIEW_CONVERT_EXPR
545 || code
== BIT_FIELD_REF
)
546 && TREE_CODE (TREE_OPERAND (rhs1
, 0)) == SSA_NAME
)
550 case tcc_declaration
:
557 if (code
== ADDR_EXPR
)
558 return (is_gimple_min_invariant (rhs1
)
559 ? VN_CONSTANT
: VN_REFERENCE
);
560 else if (code
== CONSTRUCTOR
)
573 /* Lookup a value id for CONSTANT and return it. If it does not
577 get_constant_value_id (tree constant
)
579 vn_constant_s
**slot
;
580 struct vn_constant_s vc
;
582 vc
.hashcode
= vn_hash_constant_with_type (constant
);
583 vc
.constant
= constant
;
584 slot
= constant_to_value_id
->find_slot (&vc
, NO_INSERT
);
586 return (*slot
)->value_id
;
590 /* Lookup a value id for CONSTANT, and if it does not exist, create a
591 new one and return it. If it does exist, return it. */
594 get_or_alloc_constant_value_id (tree constant
)
596 vn_constant_s
**slot
;
597 struct vn_constant_s vc
;
600 /* If the hashtable isn't initialized we're not running from PRE and thus
601 do not need value-ids. */
602 if (!constant_to_value_id
)
605 vc
.hashcode
= vn_hash_constant_with_type (constant
);
606 vc
.constant
= constant
;
607 slot
= constant_to_value_id
->find_slot (&vc
, INSERT
);
609 return (*slot
)->value_id
;
611 vcp
= XNEW (struct vn_constant_s
);
612 vcp
->hashcode
= vc
.hashcode
;
613 vcp
->constant
= constant
;
614 vcp
->value_id
= get_next_value_id ();
616 bitmap_set_bit (constant_value_ids
, vcp
->value_id
);
617 return vcp
->value_id
;
620 /* Return true if V is a value id for a constant. */
623 value_id_constant_p (unsigned int v
)
625 return bitmap_bit_p (constant_value_ids
, v
);
628 /* Compute the hash for a reference operand VRO1. */
631 vn_reference_op_compute_hash (const vn_reference_op_t vro1
, inchash::hash
&hstate
)
633 hstate
.add_int (vro1
->opcode
);
635 inchash::add_expr (vro1
->op0
, hstate
);
637 inchash::add_expr (vro1
->op1
, hstate
);
639 inchash::add_expr (vro1
->op2
, hstate
);
642 /* Compute a hash for the reference operation VR1 and return it. */
645 vn_reference_compute_hash (const vn_reference_t vr1
)
647 inchash::hash hstate
;
650 vn_reference_op_t vro
;
654 FOR_EACH_VEC_ELT (vr1
->operands
, i
, vro
)
656 if (vro
->opcode
== MEM_REF
)
658 else if (vro
->opcode
!= ADDR_EXPR
)
660 if (maybe_ne (vro
->off
, -1))
662 if (known_eq (off
, -1))
668 if (maybe_ne (off
, -1)
669 && maybe_ne (off
, 0))
670 hstate
.add_poly_int (off
);
673 && vro
->opcode
== ADDR_EXPR
)
677 tree op
= TREE_OPERAND (vro
->op0
, 0);
678 hstate
.add_int (TREE_CODE (op
));
679 inchash::add_expr (op
, hstate
);
683 vn_reference_op_compute_hash (vro
, hstate
);
686 result
= hstate
.end ();
687 /* ??? We would ICE later if we hash instead of adding that in. */
689 result
+= SSA_NAME_VERSION (vr1
->vuse
);
694 /* Return true if reference operations VR1 and VR2 are equivalent. This
695 means they have the same set of operands and vuses. */
698 vn_reference_eq (const_vn_reference_t
const vr1
, const_vn_reference_t
const vr2
)
702 /* Early out if this is not a hash collision. */
703 if (vr1
->hashcode
!= vr2
->hashcode
)
706 /* The VOP needs to be the same. */
707 if (vr1
->vuse
!= vr2
->vuse
)
710 /* If the operands are the same we are done. */
711 if (vr1
->operands
== vr2
->operands
)
714 if (!expressions_equal_p (TYPE_SIZE (vr1
->type
), TYPE_SIZE (vr2
->type
)))
717 if (INTEGRAL_TYPE_P (vr1
->type
)
718 && INTEGRAL_TYPE_P (vr2
->type
))
720 if (TYPE_PRECISION (vr1
->type
) != TYPE_PRECISION (vr2
->type
))
723 else if (INTEGRAL_TYPE_P (vr1
->type
)
724 && (TYPE_PRECISION (vr1
->type
)
725 != TREE_INT_CST_LOW (TYPE_SIZE (vr1
->type
))))
727 else if (INTEGRAL_TYPE_P (vr2
->type
)
728 && (TYPE_PRECISION (vr2
->type
)
729 != TREE_INT_CST_LOW (TYPE_SIZE (vr2
->type
))))
736 poly_int64 off1
= 0, off2
= 0;
737 vn_reference_op_t vro1
, vro2
;
738 vn_reference_op_s tem1
, tem2
;
739 bool deref1
= false, deref2
= false;
740 for (; vr1
->operands
.iterate (i
, &vro1
); i
++)
742 if (vro1
->opcode
== MEM_REF
)
744 /* Do not look through a storage order barrier. */
745 else if (vro1
->opcode
== VIEW_CONVERT_EXPR
&& vro1
->reverse
)
747 if (known_eq (vro1
->off
, -1))
751 for (; vr2
->operands
.iterate (j
, &vro2
); j
++)
753 if (vro2
->opcode
== MEM_REF
)
755 /* Do not look through a storage order barrier. */
756 else if (vro2
->opcode
== VIEW_CONVERT_EXPR
&& vro2
->reverse
)
758 if (known_eq (vro2
->off
, -1))
762 if (maybe_ne (off1
, off2
))
764 if (deref1
&& vro1
->opcode
== ADDR_EXPR
)
766 memset (&tem1
, 0, sizeof (tem1
));
767 tem1
.op0
= TREE_OPERAND (vro1
->op0
, 0);
768 tem1
.type
= TREE_TYPE (tem1
.op0
);
769 tem1
.opcode
= TREE_CODE (tem1
.op0
);
773 if (deref2
&& vro2
->opcode
== ADDR_EXPR
)
775 memset (&tem2
, 0, sizeof (tem2
));
776 tem2
.op0
= TREE_OPERAND (vro2
->op0
, 0);
777 tem2
.type
= TREE_TYPE (tem2
.op0
);
778 tem2
.opcode
= TREE_CODE (tem2
.op0
);
782 if (deref1
!= deref2
)
784 if (!vn_reference_op_eq (vro1
, vro2
))
789 while (vr1
->operands
.length () != i
790 || vr2
->operands
.length () != j
);
795 /* Copy the operations present in load/store REF into RESULT, a vector of
796 vn_reference_op_s's. */
799 copy_reference_ops_from_ref (tree ref
, vec
<vn_reference_op_s
> *result
)
801 /* For non-calls, store the information that makes up the address. */
805 vn_reference_op_s temp
;
807 memset (&temp
, 0, sizeof (temp
));
808 temp
.type
= TREE_TYPE (ref
);
809 temp
.opcode
= TREE_CODE (ref
);
815 temp
.op0
= TREE_OPERAND (ref
, 1);
818 temp
.op0
= TREE_OPERAND (ref
, 1);
822 /* The base address gets its own vn_reference_op_s structure. */
823 temp
.op0
= TREE_OPERAND (ref
, 1);
824 if (!mem_ref_offset (ref
).to_shwi (&temp
.off
))
826 temp
.clique
= MR_DEPENDENCE_CLIQUE (ref
);
827 temp
.base
= MR_DEPENDENCE_BASE (ref
);
828 temp
.reverse
= REF_REVERSE_STORAGE_ORDER (ref
);
831 /* The base address gets its own vn_reference_op_s structure. */
832 temp
.op0
= TMR_INDEX (ref
);
833 temp
.op1
= TMR_STEP (ref
);
834 temp
.op2
= TMR_OFFSET (ref
);
835 temp
.clique
= MR_DEPENDENCE_CLIQUE (ref
);
836 temp
.base
= MR_DEPENDENCE_BASE (ref
);
837 result
->safe_push (temp
);
838 memset (&temp
, 0, sizeof (temp
));
839 temp
.type
= NULL_TREE
;
840 temp
.opcode
= ERROR_MARK
;
841 temp
.op0
= TMR_INDEX2 (ref
);
845 /* Record bits, position and storage order. */
846 temp
.op0
= TREE_OPERAND (ref
, 1);
847 temp
.op1
= TREE_OPERAND (ref
, 2);
848 if (!multiple_p (bit_field_offset (ref
), BITS_PER_UNIT
, &temp
.off
))
850 temp
.reverse
= REF_REVERSE_STORAGE_ORDER (ref
);
853 /* The field decl is enough to unambiguously specify the field,
854 a matching type is not necessary and a mismatching type
855 is always a spurious difference. */
856 temp
.type
= NULL_TREE
;
857 temp
.op0
= TREE_OPERAND (ref
, 1);
858 temp
.op1
= TREE_OPERAND (ref
, 2);
860 tree this_offset
= component_ref_field_offset (ref
);
862 && poly_int_tree_p (this_offset
))
864 tree bit_offset
= DECL_FIELD_BIT_OFFSET (TREE_OPERAND (ref
, 1));
865 if (TREE_INT_CST_LOW (bit_offset
) % BITS_PER_UNIT
== 0)
868 = (wi::to_poly_offset (this_offset
)
869 + (wi::to_offset (bit_offset
) >> LOG2_BITS_PER_UNIT
));
870 /* Probibit value-numbering zero offset components
871 of addresses the same before the pass folding
872 __builtin_object_size had a chance to run
873 (checking cfun->after_inlining does the
875 if (TREE_CODE (orig
) != ADDR_EXPR
877 || cfun
->after_inlining
)
878 off
.to_shwi (&temp
.off
);
883 case ARRAY_RANGE_REF
:
886 tree eltype
= TREE_TYPE (TREE_TYPE (TREE_OPERAND (ref
, 0)));
887 /* Record index as operand. */
888 temp
.op0
= TREE_OPERAND (ref
, 1);
889 /* Always record lower bounds and element size. */
890 temp
.op1
= array_ref_low_bound (ref
);
891 /* But record element size in units of the type alignment. */
892 temp
.op2
= TREE_OPERAND (ref
, 3);
893 temp
.align
= eltype
->type_common
.align
;
895 temp
.op2
= size_binop (EXACT_DIV_EXPR
, TYPE_SIZE_UNIT (eltype
),
896 size_int (TYPE_ALIGN_UNIT (eltype
)));
897 if (poly_int_tree_p (temp
.op0
)
898 && poly_int_tree_p (temp
.op1
)
899 && TREE_CODE (temp
.op2
) == INTEGER_CST
)
901 poly_offset_int off
= ((wi::to_poly_offset (temp
.op0
)
902 - wi::to_poly_offset (temp
.op1
))
903 * wi::to_offset (temp
.op2
)
904 * vn_ref_op_align_unit (&temp
));
905 off
.to_shwi (&temp
.off
);
910 if (DECL_HARD_REGISTER (ref
))
919 /* Canonicalize decls to MEM[&decl] which is what we end up with
920 when valueizing MEM[ptr] with ptr = &decl. */
921 temp
.opcode
= MEM_REF
;
922 temp
.op0
= build_int_cst (build_pointer_type (TREE_TYPE (ref
)), 0);
924 result
->safe_push (temp
);
925 temp
.opcode
= ADDR_EXPR
;
926 temp
.op0
= build1 (ADDR_EXPR
, TREE_TYPE (temp
.op0
), ref
);
927 temp
.type
= TREE_TYPE (temp
.op0
);
942 if (is_gimple_min_invariant (ref
))
948 /* These are only interesting for their operands, their
949 existence, and their type. They will never be the last
950 ref in the chain of references (IE they require an
951 operand), so we don't have to put anything
952 for op* as it will be handled by the iteration */
956 case VIEW_CONVERT_EXPR
:
958 temp
.reverse
= storage_order_barrier_p (ref
);
961 /* This is only interesting for its constant offset. */
962 temp
.off
= TREE_INT_CST_LOW (TYPE_SIZE_UNIT (TREE_TYPE (ref
)));
967 result
->safe_push (temp
);
969 if (REFERENCE_CLASS_P (ref
)
970 || TREE_CODE (ref
) == MODIFY_EXPR
971 || TREE_CODE (ref
) == WITH_SIZE_EXPR
972 || (TREE_CODE (ref
) == ADDR_EXPR
973 && !is_gimple_min_invariant (ref
)))
974 ref
= TREE_OPERAND (ref
, 0);
980 /* Build a alias-oracle reference abstraction in *REF from the vn_reference
981 operands in *OPS, the reference alias set SET and the reference type TYPE.
982 Return true if something useful was produced. */
985 ao_ref_init_from_vn_reference (ao_ref
*ref
,
986 alias_set_type set
, alias_set_type base_set
,
987 tree type
, vec
<vn_reference_op_s
> ops
)
989 vn_reference_op_t op
;
991 tree base
= NULL_TREE
;
993 poly_offset_int offset
= 0;
994 poly_offset_int max_size
;
995 poly_offset_int size
= -1;
996 tree size_tree
= NULL_TREE
;
998 /* First get the final access size from just the outermost expression. */
1000 if (op
->opcode
== COMPONENT_REF
)
1001 size_tree
= DECL_SIZE (op
->op0
);
1002 else if (op
->opcode
== BIT_FIELD_REF
)
1003 size_tree
= op
->op0
;
1006 machine_mode mode
= TYPE_MODE (type
);
1007 if (mode
== BLKmode
)
1008 size_tree
= TYPE_SIZE (type
);
1010 size
= GET_MODE_BITSIZE (mode
);
1012 if (size_tree
!= NULL_TREE
1013 && poly_int_tree_p (size_tree
))
1014 size
= wi::to_poly_offset (size_tree
);
1016 /* Initially, maxsize is the same as the accessed element size.
1017 In the following it will only grow (or become -1). */
1020 /* Compute cumulative bit-offset for nested component-refs and array-refs,
1021 and find the ultimate containing object. */
1022 FOR_EACH_VEC_ELT (ops
, i
, op
)
1026 /* These may be in the reference ops, but we cannot do anything
1027 sensible with them here. */
1029 /* Apart from ADDR_EXPR arguments to MEM_REF. */
1030 if (base
!= NULL_TREE
1031 && TREE_CODE (base
) == MEM_REF
1033 && DECL_P (TREE_OPERAND (op
->op0
, 0)))
1035 vn_reference_op_t pop
= &ops
[i
-1];
1036 base
= TREE_OPERAND (op
->op0
, 0);
1037 if (known_eq (pop
->off
, -1))
1043 offset
+= pop
->off
* BITS_PER_UNIT
;
1051 /* Record the base objects. */
1053 *op0_p
= build2 (MEM_REF
, op
->type
,
1054 NULL_TREE
, op
->op0
);
1055 MR_DEPENDENCE_CLIQUE (*op0_p
) = op
->clique
;
1056 MR_DEPENDENCE_BASE (*op0_p
) = op
->base
;
1057 op0_p
= &TREE_OPERAND (*op0_p
, 0);
1068 /* And now the usual component-reference style ops. */
1070 offset
+= wi::to_poly_offset (op
->op1
);
1075 tree field
= op
->op0
;
1076 /* We do not have a complete COMPONENT_REF tree here so we
1077 cannot use component_ref_field_offset. Do the interesting
1079 tree this_offset
= DECL_FIELD_OFFSET (field
);
1081 if (op
->op1
|| !poly_int_tree_p (this_offset
))
1085 poly_offset_int woffset
= (wi::to_poly_offset (this_offset
)
1086 << LOG2_BITS_PER_UNIT
);
1087 woffset
+= wi::to_offset (DECL_FIELD_BIT_OFFSET (field
));
1093 case ARRAY_RANGE_REF
:
1095 /* We recorded the lower bound and the element size. */
1096 if (!poly_int_tree_p (op
->op0
)
1097 || !poly_int_tree_p (op
->op1
)
1098 || TREE_CODE (op
->op2
) != INTEGER_CST
)
1102 poly_offset_int woffset
1103 = wi::sext (wi::to_poly_offset (op
->op0
)
1104 - wi::to_poly_offset (op
->op1
),
1105 TYPE_PRECISION (TREE_TYPE (op
->op0
)));
1106 woffset
*= wi::to_offset (op
->op2
) * vn_ref_op_align_unit (op
);
1107 woffset
<<= LOG2_BITS_PER_UNIT
;
1119 case VIEW_CONVERT_EXPR
:
1136 if (base
== NULL_TREE
)
1139 ref
->ref
= NULL_TREE
;
1141 ref
->ref_alias_set
= set
;
1142 ref
->base_alias_set
= base_set
;
1143 /* We discount volatiles from value-numbering elsewhere. */
1144 ref
->volatile_p
= false;
1146 if (!size
.to_shwi (&ref
->size
) || maybe_lt (ref
->size
, 0))
1154 if (!offset
.to_shwi (&ref
->offset
))
1161 if (!max_size
.to_shwi (&ref
->max_size
) || maybe_lt (ref
->max_size
, 0))
1167 /* Copy the operations present in load/store/call REF into RESULT, a vector of
1168 vn_reference_op_s's. */
1171 copy_reference_ops_from_call (gcall
*call
,
1172 vec
<vn_reference_op_s
> *result
)
1174 vn_reference_op_s temp
;
1176 tree lhs
= gimple_call_lhs (call
);
1179 /* If 2 calls have a different non-ssa lhs, vdef value numbers should be
1180 different. By adding the lhs here in the vector, we ensure that the
1181 hashcode is different, guaranteeing a different value number. */
1182 if (lhs
&& TREE_CODE (lhs
) != SSA_NAME
)
1184 memset (&temp
, 0, sizeof (temp
));
1185 temp
.opcode
= MODIFY_EXPR
;
1186 temp
.type
= TREE_TYPE (lhs
);
1189 result
->safe_push (temp
);
1192 /* Copy the type, opcode, function, static chain and EH region, if any. */
1193 memset (&temp
, 0, sizeof (temp
));
1194 temp
.type
= gimple_call_fntype (call
);
1195 temp
.opcode
= CALL_EXPR
;
1196 temp
.op0
= gimple_call_fn (call
);
1197 temp
.op1
= gimple_call_chain (call
);
1198 if (stmt_could_throw_p (cfun
, call
) && (lr
= lookup_stmt_eh_lp (call
)) > 0)
1199 temp
.op2
= size_int (lr
);
1201 result
->safe_push (temp
);
1203 /* Copy the call arguments. As they can be references as well,
1204 just chain them together. */
1205 for (i
= 0; i
< gimple_call_num_args (call
); ++i
)
1207 tree callarg
= gimple_call_arg (call
, i
);
1208 copy_reference_ops_from_ref (callarg
, result
);
1212 /* Fold *& at position *I_P in a vn_reference_op_s vector *OPS. Updates
1213 *I_P to point to the last element of the replacement. */
1215 vn_reference_fold_indirect (vec
<vn_reference_op_s
> *ops
,
1218 unsigned int i
= *i_p
;
1219 vn_reference_op_t op
= &(*ops
)[i
];
1220 vn_reference_op_t mem_op
= &(*ops
)[i
- 1];
1222 poly_int64 addr_offset
= 0;
1224 /* The only thing we have to do is from &OBJ.foo.bar add the offset
1225 from .foo.bar to the preceding MEM_REF offset and replace the
1226 address with &OBJ. */
1227 addr_base
= get_addr_base_and_unit_offset_1 (TREE_OPERAND (op
->op0
, 0),
1228 &addr_offset
, vn_valueize
);
1229 gcc_checking_assert (addr_base
&& TREE_CODE (addr_base
) != MEM_REF
);
1230 if (addr_base
!= TREE_OPERAND (op
->op0
, 0))
1233 = (poly_offset_int::from (wi::to_poly_wide (mem_op
->op0
),
1236 mem_op
->op0
= wide_int_to_tree (TREE_TYPE (mem_op
->op0
), off
);
1237 op
->op0
= build_fold_addr_expr (addr_base
);
1238 if (tree_fits_shwi_p (mem_op
->op0
))
1239 mem_op
->off
= tree_to_shwi (mem_op
->op0
);
1247 /* Fold *& at position *I_P in a vn_reference_op_s vector *OPS. Updates
1248 *I_P to point to the last element of the replacement. */
1250 vn_reference_maybe_forwprop_address (vec
<vn_reference_op_s
> *ops
,
1253 bool changed
= false;
1254 vn_reference_op_t op
;
1258 unsigned int i
= *i_p
;
1260 vn_reference_op_t mem_op
= &(*ops
)[i
- 1];
1262 enum tree_code code
;
1263 poly_offset_int off
;
1265 def_stmt
= SSA_NAME_DEF_STMT (op
->op0
);
1266 if (!is_gimple_assign (def_stmt
))
1269 code
= gimple_assign_rhs_code (def_stmt
);
1270 if (code
!= ADDR_EXPR
1271 && code
!= POINTER_PLUS_EXPR
)
1274 off
= poly_offset_int::from (wi::to_poly_wide (mem_op
->op0
), SIGNED
);
1276 /* The only thing we have to do is from &OBJ.foo.bar add the offset
1277 from .foo.bar to the preceding MEM_REF offset and replace the
1278 address with &OBJ. */
1279 if (code
== ADDR_EXPR
)
1281 tree addr
, addr_base
;
1282 poly_int64 addr_offset
;
1284 addr
= gimple_assign_rhs1 (def_stmt
);
1285 addr_base
= get_addr_base_and_unit_offset_1 (TREE_OPERAND (addr
, 0),
1288 /* If that didn't work because the address isn't invariant propagate
1289 the reference tree from the address operation in case the current
1290 dereference isn't offsetted. */
1292 && *i_p
== ops
->length () - 1
1293 && known_eq (off
, 0)
1294 /* This makes us disable this transform for PRE where the
1295 reference ops might be also used for code insertion which
1297 && default_vn_walk_kind
== VN_WALKREWRITE
)
1299 auto_vec
<vn_reference_op_s
, 32> tem
;
1300 copy_reference_ops_from_ref (TREE_OPERAND (addr
, 0), &tem
);
1301 /* Make sure to preserve TBAA info. The only objects not
1302 wrapped in MEM_REFs that can have their address taken are
1304 if (tem
.length () >= 2
1305 && tem
[tem
.length () - 2].opcode
== MEM_REF
)
1307 vn_reference_op_t new_mem_op
= &tem
[tem
.length () - 2];
1309 = wide_int_to_tree (TREE_TYPE (mem_op
->op0
),
1310 wi::to_poly_wide (new_mem_op
->op0
));
1313 gcc_assert (tem
.last ().opcode
== STRING_CST
);
1316 ops
->safe_splice (tem
);
1321 || TREE_CODE (addr_base
) != MEM_REF
1322 || (TREE_CODE (TREE_OPERAND (addr_base
, 0)) == SSA_NAME
1323 && SSA_NAME_OCCURS_IN_ABNORMAL_PHI (TREE_OPERAND (addr_base
,
1328 off
+= mem_ref_offset (addr_base
);
1329 op
->op0
= TREE_OPERAND (addr_base
, 0);
1334 ptr
= gimple_assign_rhs1 (def_stmt
);
1335 ptroff
= gimple_assign_rhs2 (def_stmt
);
1336 if (TREE_CODE (ptr
) != SSA_NAME
1337 || SSA_NAME_OCCURS_IN_ABNORMAL_PHI (ptr
)
1338 /* Make sure to not endlessly recurse.
1339 See gcc.dg/tree-ssa/20040408-1.c for an example. Can easily
1340 happen when we value-number a PHI to its backedge value. */
1341 || SSA_VAL (ptr
) == op
->op0
1342 || !poly_int_tree_p (ptroff
))
1345 off
+= wi::to_poly_offset (ptroff
);
1349 mem_op
->op0
= wide_int_to_tree (TREE_TYPE (mem_op
->op0
), off
);
1350 if (tree_fits_shwi_p (mem_op
->op0
))
1351 mem_op
->off
= tree_to_shwi (mem_op
->op0
);
1354 /* ??? Can end up with endless recursion here!?
1355 gcc.c-torture/execute/strcmp-1.c */
1356 if (TREE_CODE (op
->op0
) == SSA_NAME
)
1357 op
->op0
= SSA_VAL (op
->op0
);
1358 if (TREE_CODE (op
->op0
) != SSA_NAME
)
1359 op
->opcode
= TREE_CODE (op
->op0
);
1364 while (TREE_CODE (op
->op0
) == SSA_NAME
);
1366 /* Fold a remaining *&. */
1367 if (TREE_CODE (op
->op0
) == ADDR_EXPR
)
1368 vn_reference_fold_indirect (ops
, i_p
);
1373 /* Optimize the reference REF to a constant if possible or return
1374 NULL_TREE if not. */
1377 fully_constant_vn_reference_p (vn_reference_t ref
)
1379 vec
<vn_reference_op_s
> operands
= ref
->operands
;
1380 vn_reference_op_t op
;
1382 /* Try to simplify the translated expression if it is
1383 a call to a builtin function with at most two arguments. */
1385 if (op
->opcode
== CALL_EXPR
1386 && TREE_CODE (op
->op0
) == ADDR_EXPR
1387 && TREE_CODE (TREE_OPERAND (op
->op0
, 0)) == FUNCTION_DECL
1388 && fndecl_built_in_p (TREE_OPERAND (op
->op0
, 0))
1389 && operands
.length () >= 2
1390 && operands
.length () <= 3)
1392 vn_reference_op_t arg0
, arg1
= NULL
;
1393 bool anyconst
= false;
1394 arg0
= &operands
[1];
1395 if (operands
.length () > 2)
1396 arg1
= &operands
[2];
1397 if (TREE_CODE_CLASS (arg0
->opcode
) == tcc_constant
1398 || (arg0
->opcode
== ADDR_EXPR
1399 && is_gimple_min_invariant (arg0
->op0
)))
1402 && (TREE_CODE_CLASS (arg1
->opcode
) == tcc_constant
1403 || (arg1
->opcode
== ADDR_EXPR
1404 && is_gimple_min_invariant (arg1
->op0
))))
1408 tree folded
= build_call_expr (TREE_OPERAND (op
->op0
, 0),
1411 arg1
? arg1
->op0
: NULL
);
1413 && TREE_CODE (folded
) == NOP_EXPR
)
1414 folded
= TREE_OPERAND (folded
, 0);
1416 && is_gimple_min_invariant (folded
))
1421 /* Simplify reads from constants or constant initializers. */
1422 else if (BITS_PER_UNIT
== 8
1423 && COMPLETE_TYPE_P (ref
->type
)
1424 && is_gimple_reg_type (ref
->type
))
1428 if (INTEGRAL_TYPE_P (ref
->type
))
1429 size
= TYPE_PRECISION (ref
->type
);
1430 else if (tree_fits_shwi_p (TYPE_SIZE (ref
->type
)))
1431 size
= tree_to_shwi (TYPE_SIZE (ref
->type
));
1434 if (size
% BITS_PER_UNIT
!= 0
1435 || size
> MAX_BITSIZE_MODE_ANY_MODE
)
1437 size
/= BITS_PER_UNIT
;
1439 for (i
= 0; i
< operands
.length (); ++i
)
1441 if (TREE_CODE_CLASS (operands
[i
].opcode
) == tcc_constant
)
1446 if (known_eq (operands
[i
].off
, -1))
1448 off
+= operands
[i
].off
;
1449 if (operands
[i
].opcode
== MEM_REF
)
1455 vn_reference_op_t base
= &operands
[--i
];
1456 tree ctor
= error_mark_node
;
1457 tree decl
= NULL_TREE
;
1458 if (TREE_CODE_CLASS (base
->opcode
) == tcc_constant
)
1460 else if (base
->opcode
== MEM_REF
1461 && base
[1].opcode
== ADDR_EXPR
1462 && (TREE_CODE (TREE_OPERAND (base
[1].op0
, 0)) == VAR_DECL
1463 || TREE_CODE (TREE_OPERAND (base
[1].op0
, 0)) == CONST_DECL
1464 || TREE_CODE (TREE_OPERAND (base
[1].op0
, 0)) == STRING_CST
))
1466 decl
= TREE_OPERAND (base
[1].op0
, 0);
1467 if (TREE_CODE (decl
) == STRING_CST
)
1470 ctor
= ctor_for_folding (decl
);
1472 if (ctor
== NULL_TREE
)
1473 return build_zero_cst (ref
->type
);
1474 else if (ctor
!= error_mark_node
)
1476 HOST_WIDE_INT const_off
;
1479 tree res
= fold_ctor_reference (ref
->type
, ctor
,
1480 off
* BITS_PER_UNIT
,
1481 size
* BITS_PER_UNIT
, decl
);
1484 STRIP_USELESS_TYPE_CONVERSION (res
);
1485 if (is_gimple_min_invariant (res
))
1489 else if (off
.is_constant (&const_off
))
1491 unsigned char buf
[MAX_BITSIZE_MODE_ANY_MODE
/ BITS_PER_UNIT
];
1492 int len
= native_encode_expr (ctor
, buf
, size
, const_off
);
1494 return native_interpret_expr (ref
->type
, buf
, len
);
1502 /* Return true if OPS contain a storage order barrier. */
1505 contains_storage_order_barrier_p (vec
<vn_reference_op_s
> ops
)
1507 vn_reference_op_t op
;
1510 FOR_EACH_VEC_ELT (ops
, i
, op
)
1511 if (op
->opcode
== VIEW_CONVERT_EXPR
&& op
->reverse
)
1517 /* Transform any SSA_NAME's in a vector of vn_reference_op_s
1518 structures into their value numbers. This is done in-place, and
1519 the vector passed in is returned. *VALUEIZED_ANYTHING will specify
1520 whether any operands were valueized. */
1522 static vec
<vn_reference_op_s
>
1523 valueize_refs_1 (vec
<vn_reference_op_s
> orig
, bool *valueized_anything
,
1524 bool with_avail
= false)
1526 vn_reference_op_t vro
;
1529 *valueized_anything
= false;
1531 FOR_EACH_VEC_ELT (orig
, i
, vro
)
1533 if (vro
->opcode
== SSA_NAME
1534 || (vro
->op0
&& TREE_CODE (vro
->op0
) == SSA_NAME
))
1536 tree tem
= with_avail
? vn_valueize (vro
->op0
) : SSA_VAL (vro
->op0
);
1537 if (tem
!= vro
->op0
)
1539 *valueized_anything
= true;
1542 /* If it transforms from an SSA_NAME to a constant, update
1544 if (TREE_CODE (vro
->op0
) != SSA_NAME
&& vro
->opcode
== SSA_NAME
)
1545 vro
->opcode
= TREE_CODE (vro
->op0
);
1547 if (vro
->op1
&& TREE_CODE (vro
->op1
) == SSA_NAME
)
1549 tree tem
= with_avail
? vn_valueize (vro
->op1
) : SSA_VAL (vro
->op1
);
1550 if (tem
!= vro
->op1
)
1552 *valueized_anything
= true;
1556 if (vro
->op2
&& TREE_CODE (vro
->op2
) == SSA_NAME
)
1558 tree tem
= with_avail
? vn_valueize (vro
->op2
) : SSA_VAL (vro
->op2
);
1559 if (tem
!= vro
->op2
)
1561 *valueized_anything
= true;
1565 /* If it transforms from an SSA_NAME to an address, fold with
1566 a preceding indirect reference. */
1569 && TREE_CODE (vro
->op0
) == ADDR_EXPR
1570 && orig
[i
- 1].opcode
== MEM_REF
)
1572 if (vn_reference_fold_indirect (&orig
, &i
))
1573 *valueized_anything
= true;
1576 && vro
->opcode
== SSA_NAME
1577 && orig
[i
- 1].opcode
== MEM_REF
)
1579 if (vn_reference_maybe_forwprop_address (&orig
, &i
))
1580 *valueized_anything
= true;
1582 /* If it transforms a non-constant ARRAY_REF into a constant
1583 one, adjust the constant offset. */
1584 else if (vro
->opcode
== ARRAY_REF
1585 && known_eq (vro
->off
, -1)
1586 && poly_int_tree_p (vro
->op0
)
1587 && poly_int_tree_p (vro
->op1
)
1588 && TREE_CODE (vro
->op2
) == INTEGER_CST
)
1590 poly_offset_int off
= ((wi::to_poly_offset (vro
->op0
)
1591 - wi::to_poly_offset (vro
->op1
))
1592 * wi::to_offset (vro
->op2
)
1593 * vn_ref_op_align_unit (vro
));
1594 off
.to_shwi (&vro
->off
);
1601 static vec
<vn_reference_op_s
>
1602 valueize_refs (vec
<vn_reference_op_s
> orig
)
1605 return valueize_refs_1 (orig
, &tem
);
1608 static vec
<vn_reference_op_s
> shared_lookup_references
;
1610 /* Create a vector of vn_reference_op_s structures from REF, a
1611 REFERENCE_CLASS_P tree. The vector is shared among all callers of
1612 this function. *VALUEIZED_ANYTHING will specify whether any
1613 operands were valueized. */
1615 static vec
<vn_reference_op_s
>
1616 valueize_shared_reference_ops_from_ref (tree ref
, bool *valueized_anything
)
1620 shared_lookup_references
.truncate (0);
1621 copy_reference_ops_from_ref (ref
, &shared_lookup_references
);
1622 shared_lookup_references
= valueize_refs_1 (shared_lookup_references
,
1623 valueized_anything
);
1624 return shared_lookup_references
;
1627 /* Create a vector of vn_reference_op_s structures from CALL, a
1628 call statement. The vector is shared among all callers of
1631 static vec
<vn_reference_op_s
>
1632 valueize_shared_reference_ops_from_call (gcall
*call
)
1636 shared_lookup_references
.truncate (0);
1637 copy_reference_ops_from_call (call
, &shared_lookup_references
);
1638 shared_lookup_references
= valueize_refs (shared_lookup_references
);
1639 return shared_lookup_references
;
1642 /* Lookup a SCCVN reference operation VR in the current hash table.
1643 Returns the resulting value number if it exists in the hash table,
1644 NULL_TREE otherwise. VNRESULT will be filled in with the actual
1645 vn_reference_t stored in the hashtable if something is found. */
1648 vn_reference_lookup_1 (vn_reference_t vr
, vn_reference_t
*vnresult
)
1650 vn_reference_s
**slot
;
1653 hash
= vr
->hashcode
;
1654 slot
= valid_info
->references
->find_slot_with_hash (vr
, hash
, NO_INSERT
);
1658 *vnresult
= (vn_reference_t
)*slot
;
1659 return ((vn_reference_t
)*slot
)->result
;
1666 /* Partial definition tracking support. */
1670 HOST_WIDE_INT offset
;
1677 HOST_WIDE_INT offset
;
1681 /* Context for alias walking. */
1683 struct vn_walk_cb_data
1685 vn_walk_cb_data (vn_reference_t vr_
, tree orig_ref_
, tree
*last_vuse_ptr_
,
1686 vn_lookup_kind vn_walk_kind_
, bool tbaa_p_
, tree mask_
)
1687 : vr (vr_
), last_vuse_ptr (last_vuse_ptr_
), last_vuse (NULL_TREE
),
1688 mask (mask_
), masked_result (NULL_TREE
), vn_walk_kind (vn_walk_kind_
),
1689 tbaa_p (tbaa_p_
), saved_operands (vNULL
), first_set (-2),
1690 first_base_set (-2), known_ranges (NULL
)
1693 last_vuse_ptr
= &last_vuse
;
1694 ao_ref_init (&orig_ref
, orig_ref_
);
1697 wide_int w
= wi::to_wide (mask
);
1698 unsigned int pos
= 0, prec
= w
.get_precision ();
1700 pd
.rhs
= build_constructor (NULL_TREE
, NULL
);
1701 /* When bitwise and with a constant is done on a memory load,
1702 we don't really need all the bits to be defined or defined
1703 to constants, we don't really care what is in the position
1704 corresponding to 0 bits in the mask.
1705 So, push the ranges of those 0 bits in the mask as artificial
1706 zero stores and let the partial def handling code do the
1710 int tz
= wi::ctz (w
);
1711 if (pos
+ tz
> prec
)
1715 if (BYTES_BIG_ENDIAN
)
1716 pd
.offset
= prec
- pos
- tz
;
1720 void *r
= push_partial_def (pd
, 0, 0, 0, prec
);
1721 gcc_assert (r
== NULL_TREE
);
1726 w
= wi::lrshift (w
, tz
);
1727 tz
= wi::ctz (wi::bit_not (w
));
1728 if (pos
+ tz
> prec
)
1731 w
= wi::lrshift (w
, tz
);
1735 ~vn_walk_cb_data ();
1736 void *finish (alias_set_type
, alias_set_type
, tree
);
1737 void *push_partial_def (pd_data pd
,
1738 alias_set_type
, alias_set_type
, HOST_WIDE_INT
,
1743 tree
*last_vuse_ptr
;
1747 vn_lookup_kind vn_walk_kind
;
1749 vec
<vn_reference_op_s
> saved_operands
;
1751 /* The VDEFs of partial defs we come along. */
1752 auto_vec
<pd_data
, 2> partial_defs
;
1753 /* The first defs range to avoid splay tree setup in most cases. */
1754 pd_range first_range
;
1755 alias_set_type first_set
;
1756 alias_set_type first_base_set
;
1757 splay_tree known_ranges
;
1758 obstack ranges_obstack
;
1761 vn_walk_cb_data::~vn_walk_cb_data ()
1765 splay_tree_delete (known_ranges
);
1766 obstack_free (&ranges_obstack
, NULL
);
1768 saved_operands
.release ();
1772 vn_walk_cb_data::finish (alias_set_type set
, alias_set_type base_set
, tree val
)
1774 if (first_set
!= -2)
1777 base_set
= first_base_set
;
1781 masked_result
= val
;
1784 vec
<vn_reference_op_s
> &operands
1785 = saved_operands
.exists () ? saved_operands
: vr
->operands
;
1786 return vn_reference_lookup_or_insert_for_pieces (last_vuse
, set
, base_set
,
1787 vr
->type
, operands
, val
);
1790 /* pd_range splay-tree helpers. */
1793 pd_range_compare (splay_tree_key offset1p
, splay_tree_key offset2p
)
1795 HOST_WIDE_INT offset1
= *(HOST_WIDE_INT
*)offset1p
;
1796 HOST_WIDE_INT offset2
= *(HOST_WIDE_INT
*)offset2p
;
1797 if (offset1
< offset2
)
1799 else if (offset1
> offset2
)
1805 pd_tree_alloc (int size
, void *data_
)
1807 vn_walk_cb_data
*data
= (vn_walk_cb_data
*)data_
;
1808 return obstack_alloc (&data
->ranges_obstack
, size
);
1812 pd_tree_dealloc (void *, void *)
1816 /* Push PD to the vector of partial definitions returning a
1817 value when we are ready to combine things with VUSE, SET and MAXSIZEI,
1818 NULL when we want to continue looking for partial defs or -1
1822 vn_walk_cb_data::push_partial_def (pd_data pd
,
1823 alias_set_type set
, alias_set_type base_set
,
1824 HOST_WIDE_INT offseti
,
1825 HOST_WIDE_INT maxsizei
)
1827 const HOST_WIDE_INT bufsize
= 64;
1828 /* We're using a fixed buffer for encoding so fail early if the object
1829 we want to interpret is bigger. */
1830 if (maxsizei
> bufsize
* BITS_PER_UNIT
1832 || BITS_PER_UNIT
!= 8
1833 /* Not prepared to handle PDP endian. */
1834 || BYTES_BIG_ENDIAN
!= WORDS_BIG_ENDIAN
)
1837 /* Turn too large constant stores into non-constant stores. */
1838 if (CONSTANT_CLASS_P (pd
.rhs
) && pd
.size
> bufsize
* BITS_PER_UNIT
)
1839 pd
.rhs
= error_mark_node
;
1841 /* And for non-constant or CONSTRUCTOR stores shrink them to only keep at
1842 most a partial byte before and/or after the region. */
1843 if (!CONSTANT_CLASS_P (pd
.rhs
))
1845 if (pd
.offset
< offseti
)
1847 HOST_WIDE_INT o
= ROUND_DOWN (offseti
- pd
.offset
, BITS_PER_UNIT
);
1848 gcc_assert (pd
.size
> o
);
1852 if (pd
.size
> maxsizei
)
1853 pd
.size
= maxsizei
+ ((pd
.size
- maxsizei
) % BITS_PER_UNIT
);
1856 pd
.offset
-= offseti
;
1858 bool pd_constant_p
= (TREE_CODE (pd
.rhs
) == CONSTRUCTOR
1859 || CONSTANT_CLASS_P (pd
.rhs
));
1860 if (partial_defs
.is_empty ())
1862 /* If we get a clobber upfront, fail. */
1863 if (TREE_CLOBBER_P (pd
.rhs
))
1867 partial_defs
.safe_push (pd
);
1868 first_range
.offset
= pd
.offset
;
1869 first_range
.size
= pd
.size
;
1871 first_base_set
= base_set
;
1872 last_vuse_ptr
= NULL
;
1873 /* Continue looking for partial defs. */
1879 /* ??? Optimize the case where the 2nd partial def completes things. */
1880 gcc_obstack_init (&ranges_obstack
);
1881 known_ranges
= splay_tree_new_with_allocator (pd_range_compare
, 0, 0,
1883 pd_tree_dealloc
, this);
1884 splay_tree_insert (known_ranges
,
1885 (splay_tree_key
)&first_range
.offset
,
1886 (splay_tree_value
)&first_range
);
1889 pd_range newr
= { pd
.offset
, pd
.size
};
1892 /* Lookup the predecessor of offset + 1 and see if we need to merge. */
1893 HOST_WIDE_INT loffset
= newr
.offset
+ 1;
1894 if ((n
= splay_tree_predecessor (known_ranges
, (splay_tree_key
)&loffset
))
1895 && ((r
= (pd_range
*)n
->value
), true)
1896 && ranges_known_overlap_p (r
->offset
, r
->size
+ 1,
1897 newr
.offset
, newr
.size
))
1899 /* Ignore partial defs already covered. Here we also drop shadowed
1900 clobbers arriving here at the floor. */
1901 if (known_subrange_p (newr
.offset
, newr
.size
, r
->offset
, r
->size
))
1903 r
->size
= MAX (r
->offset
+ r
->size
, newr
.offset
+ newr
.size
) - r
->offset
;
1907 /* newr.offset wasn't covered yet, insert the range. */
1908 r
= XOBNEW (&ranges_obstack
, pd_range
);
1910 splay_tree_insert (known_ranges
, (splay_tree_key
)&r
->offset
,
1911 (splay_tree_value
)r
);
1913 /* Merge r which now contains newr and is a member of the splay tree with
1914 adjacent overlapping ranges. */
1916 while ((n
= splay_tree_successor (known_ranges
, (splay_tree_key
)&r
->offset
))
1917 && ((rafter
= (pd_range
*)n
->value
), true)
1918 && ranges_known_overlap_p (r
->offset
, r
->size
+ 1,
1919 rafter
->offset
, rafter
->size
))
1921 r
->size
= MAX (r
->offset
+ r
->size
,
1922 rafter
->offset
+ rafter
->size
) - r
->offset
;
1923 splay_tree_remove (known_ranges
, (splay_tree_key
)&rafter
->offset
);
1925 /* If we get a clobber, fail. */
1926 if (TREE_CLOBBER_P (pd
.rhs
))
1928 /* Non-constants are OK as long as they are shadowed by a constant. */
1931 partial_defs
.safe_push (pd
);
1933 /* Now we have merged newr into the range tree. When we have covered
1934 [offseti, sizei] then the tree will contain exactly one node which has
1935 the desired properties and it will be 'r'. */
1936 if (!known_subrange_p (0, maxsizei
, r
->offset
, r
->size
))
1937 /* Continue looking for partial defs. */
1940 /* Now simply native encode all partial defs in reverse order. */
1941 unsigned ndefs
= partial_defs
.length ();
1942 /* We support up to 512-bit values (for V8DFmode). */
1943 unsigned char buffer
[bufsize
+ 1];
1944 unsigned char this_buffer
[bufsize
+ 1];
1947 memset (buffer
, 0, bufsize
+ 1);
1948 unsigned needed_len
= ROUND_UP (maxsizei
, BITS_PER_UNIT
) / BITS_PER_UNIT
;
1949 while (!partial_defs
.is_empty ())
1951 pd_data pd
= partial_defs
.pop ();
1953 if (TREE_CODE (pd
.rhs
) == CONSTRUCTOR
)
1955 /* Empty CONSTRUCTOR. */
1956 if (pd
.size
>= needed_len
* BITS_PER_UNIT
)
1959 len
= ROUND_UP (pd
.size
, BITS_PER_UNIT
) / BITS_PER_UNIT
;
1960 memset (this_buffer
, 0, len
);
1964 len
= native_encode_expr (pd
.rhs
, this_buffer
, bufsize
,
1965 MAX (0, -pd
.offset
) / BITS_PER_UNIT
);
1967 || len
< (ROUND_UP (pd
.size
, BITS_PER_UNIT
) / BITS_PER_UNIT
1968 - MAX (0, -pd
.offset
) / BITS_PER_UNIT
))
1970 if (dump_file
&& (dump_flags
& TDF_DETAILS
))
1971 fprintf (dump_file
, "Failed to encode %u "
1972 "partial definitions\n", ndefs
);
1977 unsigned char *p
= buffer
;
1978 HOST_WIDE_INT size
= pd
.size
;
1980 size
-= ROUND_DOWN (-pd
.offset
, BITS_PER_UNIT
);
1981 this_buffer
[len
] = 0;
1982 if (BYTES_BIG_ENDIAN
)
1984 /* LSB of this_buffer[len - 1] byte should be at
1985 pd.offset + pd.size - 1 bits in buffer. */
1986 amnt
= ((unsigned HOST_WIDE_INT
) pd
.offset
1987 + pd
.size
) % BITS_PER_UNIT
;
1989 shift_bytes_in_array_right (this_buffer
, len
+ 1, amnt
);
1990 unsigned char *q
= this_buffer
;
1991 unsigned int off
= 0;
1995 off
= pd
.offset
/ BITS_PER_UNIT
;
1996 gcc_assert (off
< needed_len
);
2000 msk
= ((1 << size
) - 1) << (BITS_PER_UNIT
- amnt
);
2001 *p
= (*p
& ~msk
) | (this_buffer
[len
] & msk
);
2006 if (TREE_CODE (pd
.rhs
) != CONSTRUCTOR
)
2007 q
= (this_buffer
+ len
2008 - (ROUND_UP (size
- amnt
, BITS_PER_UNIT
)
2010 if (pd
.offset
% BITS_PER_UNIT
)
2012 msk
= -1U << (BITS_PER_UNIT
2013 - (pd
.offset
% BITS_PER_UNIT
));
2014 *p
= (*p
& msk
) | (*q
& ~msk
);
2018 size
-= BITS_PER_UNIT
- (pd
.offset
% BITS_PER_UNIT
);
2019 gcc_assert (size
>= 0);
2023 else if (TREE_CODE (pd
.rhs
) != CONSTRUCTOR
)
2025 q
= (this_buffer
+ len
2026 - (ROUND_UP (size
- amnt
, BITS_PER_UNIT
)
2028 if (pd
.offset
% BITS_PER_UNIT
)
2031 size
-= BITS_PER_UNIT
- ((unsigned HOST_WIDE_INT
) pd
.offset
2033 gcc_assert (size
>= 0);
2036 if ((unsigned HOST_WIDE_INT
) size
/ BITS_PER_UNIT
+ off
2038 size
= (needed_len
- off
) * BITS_PER_UNIT
;
2039 memcpy (p
, q
, size
/ BITS_PER_UNIT
);
2040 if (size
% BITS_PER_UNIT
)
2043 = -1U << (BITS_PER_UNIT
- (size
% BITS_PER_UNIT
));
2044 p
+= size
/ BITS_PER_UNIT
;
2045 q
+= size
/ BITS_PER_UNIT
;
2046 *p
= (*q
& msk
) | (*p
& ~msk
);
2051 size
= MIN (size
, (HOST_WIDE_INT
) needed_len
* BITS_PER_UNIT
);
2054 /* LSB of this_buffer[0] byte should be at pd.offset bits
2057 amnt
= pd
.offset
% BITS_PER_UNIT
;
2059 shift_bytes_in_array_left (this_buffer
, len
+ 1, amnt
);
2060 unsigned int off
= pd
.offset
/ BITS_PER_UNIT
;
2061 gcc_assert (off
< needed_len
);
2063 (HOST_WIDE_INT
) (needed_len
- off
) * BITS_PER_UNIT
);
2065 if (amnt
+ size
< BITS_PER_UNIT
)
2067 /* Low amnt bits come from *p, then size bits
2068 from this_buffer[0] and the remaining again from
2070 msk
= ((1 << size
) - 1) << amnt
;
2071 *p
= (*p
& ~msk
) | (this_buffer
[0] & msk
);
2077 *p
= (*p
& ~msk
) | (this_buffer
[0] & msk
);
2079 size
-= (BITS_PER_UNIT
- amnt
);
2084 amnt
= (unsigned HOST_WIDE_INT
) pd
.offset
% BITS_PER_UNIT
;
2086 shift_bytes_in_array_left (this_buffer
, len
+ 1, amnt
);
2088 memcpy (p
, this_buffer
+ (amnt
!= 0), size
/ BITS_PER_UNIT
);
2089 p
+= size
/ BITS_PER_UNIT
;
2090 if (size
% BITS_PER_UNIT
)
2092 unsigned int msk
= -1U << (size
% BITS_PER_UNIT
);
2093 *p
= (this_buffer
[(amnt
!= 0) + size
/ BITS_PER_UNIT
]
2094 & ~msk
) | (*p
& msk
);
2099 tree type
= vr
->type
;
2100 /* Make sure to interpret in a type that has a range covering the whole
2102 if (INTEGRAL_TYPE_P (vr
->type
) && maxsizei
!= TYPE_PRECISION (vr
->type
))
2103 type
= build_nonstandard_integer_type (maxsizei
, TYPE_UNSIGNED (type
));
2105 if (BYTES_BIG_ENDIAN
)
2107 unsigned sz
= needed_len
;
2108 if (maxsizei
% BITS_PER_UNIT
)
2109 shift_bytes_in_array_right (buffer
, needed_len
,
2111 - (maxsizei
% BITS_PER_UNIT
));
2112 if (INTEGRAL_TYPE_P (type
))
2113 sz
= GET_MODE_SIZE (SCALAR_INT_TYPE_MODE (type
));
2114 if (sz
> needed_len
)
2116 memcpy (this_buffer
+ (sz
- needed_len
), buffer
, needed_len
);
2117 val
= native_interpret_expr (type
, this_buffer
, sz
);
2120 val
= native_interpret_expr (type
, buffer
, needed_len
);
2123 val
= native_interpret_expr (type
, buffer
, bufsize
);
2124 /* If we chop off bits because the types precision doesn't match the memory
2125 access size this is ok when optimizing reads but not when called from
2126 the DSE code during elimination. */
2127 if (val
&& type
!= vr
->type
)
2129 if (! int_fits_type_p (val
, vr
->type
))
2132 val
= fold_convert (vr
->type
, val
);
2137 if (dump_file
&& (dump_flags
& TDF_DETAILS
))
2139 "Successfully combined %u partial definitions\n", ndefs
);
2140 /* We are using the alias-set of the first store we encounter which
2141 should be appropriate here. */
2142 return finish (first_set
, first_base_set
, val
);
2146 if (dump_file
&& (dump_flags
& TDF_DETAILS
))
2148 "Failed to interpret %u encoded partial definitions\n", ndefs
);
2153 /* Callback for walk_non_aliased_vuses. Adjusts the vn_reference_t VR_
2154 with the current VUSE and performs the expression lookup. */
2157 vn_reference_lookup_2 (ao_ref
*op ATTRIBUTE_UNUSED
, tree vuse
, void *data_
)
2159 vn_walk_cb_data
*data
= (vn_walk_cb_data
*)data_
;
2160 vn_reference_t vr
= data
->vr
;
2161 vn_reference_s
**slot
;
2164 /* If we have partial definitions recorded we have to go through
2165 vn_reference_lookup_3. */
2166 if (!data
->partial_defs
.is_empty ())
2169 if (data
->last_vuse_ptr
)
2171 *data
->last_vuse_ptr
= vuse
;
2172 data
->last_vuse
= vuse
;
2175 /* Fixup vuse and hash. */
2177 vr
->hashcode
= vr
->hashcode
- SSA_NAME_VERSION (vr
->vuse
);
2178 vr
->vuse
= vuse_ssa_val (vuse
);
2180 vr
->hashcode
= vr
->hashcode
+ SSA_NAME_VERSION (vr
->vuse
);
2182 hash
= vr
->hashcode
;
2183 slot
= valid_info
->references
->find_slot_with_hash (vr
, hash
, NO_INSERT
);
2186 if ((*slot
)->result
&& data
->saved_operands
.exists ())
2187 return data
->finish (vr
->set
, vr
->base_set
, (*slot
)->result
);
2194 /* Lookup an existing or insert a new vn_reference entry into the
2195 value table for the VUSE, SET, TYPE, OPERANDS reference which
2196 has the value VALUE which is either a constant or an SSA name. */
2198 static vn_reference_t
2199 vn_reference_lookup_or_insert_for_pieces (tree vuse
,
2201 alias_set_type base_set
,
2203 vec
<vn_reference_op_s
,
2208 vn_reference_t result
;
2210 vr1
.vuse
= vuse
? SSA_VAL (vuse
) : NULL_TREE
;
2211 vr1
.operands
= operands
;
2214 vr1
.base_set
= base_set
;
2215 vr1
.hashcode
= vn_reference_compute_hash (&vr1
);
2216 if (vn_reference_lookup_1 (&vr1
, &result
))
2218 if (TREE_CODE (value
) == SSA_NAME
)
2219 value_id
= VN_INFO (value
)->value_id
;
2221 value_id
= get_or_alloc_constant_value_id (value
);
2222 return vn_reference_insert_pieces (vuse
, set
, base_set
, type
,
2223 operands
.copy (), value
, value_id
);
2226 /* Return a value-number for RCODE OPS... either by looking up an existing
2227 value-number for the simplified result or by inserting the operation if
2231 vn_nary_build_or_lookup_1 (gimple_match_op
*res_op
, bool insert
)
2233 tree result
= NULL_TREE
;
2234 /* We will be creating a value number for
2236 So first simplify and lookup this expression to see if it
2237 is already available. */
2238 /* For simplification valueize. */
2240 for (i
= 0; i
< res_op
->num_ops
; ++i
)
2241 if (TREE_CODE (res_op
->ops
[i
]) == SSA_NAME
)
2243 tree tem
= vn_valueize (res_op
->ops
[i
]);
2246 res_op
->ops
[i
] = tem
;
2248 /* If valueization of an operand fails (it is not available), skip
2251 if (i
== res_op
->num_ops
)
2253 mprts_hook
= vn_lookup_simplify_result
;
2254 res
= res_op
->resimplify (NULL
, vn_valueize
);
2257 gimple
*new_stmt
= NULL
;
2259 && gimple_simplified_result_is_gimple_val (res_op
))
2261 /* The expression is already available. */
2262 result
= res_op
->ops
[0];
2263 /* Valueize it, simplification returns sth in AVAIL only. */
2264 if (TREE_CODE (result
) == SSA_NAME
)
2265 result
= SSA_VAL (result
);
2269 tree val
= vn_lookup_simplify_result (res_op
);
2272 gimple_seq stmts
= NULL
;
2273 result
= maybe_push_res_to_seq (res_op
, &stmts
);
2276 gcc_assert (gimple_seq_singleton_p (stmts
));
2277 new_stmt
= gimple_seq_first_stmt (stmts
);
2281 /* The expression is already available. */
2286 /* The expression is not yet available, value-number lhs to
2287 the new SSA_NAME we created. */
2288 /* Initialize value-number information properly. */
2289 vn_ssa_aux_t result_info
= VN_INFO (result
);
2290 result_info
->valnum
= result
;
2291 result_info
->value_id
= get_next_value_id ();
2292 result_info
->visited
= 1;
2293 gimple_seq_add_stmt_without_update (&VN_INFO (result
)->expr
,
2295 result_info
->needs_insertion
= true;
2296 /* ??? PRE phi-translation inserts NARYs without corresponding
2297 SSA name result. Re-use those but set their result according
2298 to the stmt we just built. */
2299 vn_nary_op_t nary
= NULL
;
2300 vn_nary_op_lookup_stmt (new_stmt
, &nary
);
2303 gcc_assert (! nary
->predicated_values
&& nary
->u
.result
== NULL_TREE
);
2304 nary
->u
.result
= gimple_assign_lhs (new_stmt
);
2306 /* As all "inserted" statements are singleton SCCs, insert
2307 to the valid table. This is strictly needed to
2308 avoid re-generating new value SSA_NAMEs for the same
2309 expression during SCC iteration over and over (the
2310 optimistic table gets cleared after each iteration).
2311 We do not need to insert into the optimistic table, as
2312 lookups there will fall back to the valid table. */
2315 unsigned int length
= vn_nary_length_from_stmt (new_stmt
);
2317 = alloc_vn_nary_op_noinit (length
, &vn_tables_insert_obstack
);
2318 vno1
->value_id
= result_info
->value_id
;
2319 vno1
->length
= length
;
2320 vno1
->predicated_values
= 0;
2321 vno1
->u
.result
= result
;
2322 init_vn_nary_op_from_stmt (vno1
, new_stmt
);
2323 vn_nary_op_insert_into (vno1
, valid_info
->nary
, true);
2324 /* Also do not link it into the undo chain. */
2325 last_inserted_nary
= vno1
->next
;
2326 vno1
->next
= (vn_nary_op_t
)(void *)-1;
2328 if (dump_file
&& (dump_flags
& TDF_DETAILS
))
2330 fprintf (dump_file
, "Inserting name ");
2331 print_generic_expr (dump_file
, result
);
2332 fprintf (dump_file
, " for expression ");
2333 print_gimple_expr (dump_file
, new_stmt
, 0, TDF_SLIM
);
2334 fprintf (dump_file
, "\n");
2340 /* Return a value-number for RCODE OPS... either by looking up an existing
2341 value-number for the simplified result or by inserting the operation. */
2344 vn_nary_build_or_lookup (gimple_match_op
*res_op
)
2346 return vn_nary_build_or_lookup_1 (res_op
, true);
2349 /* Try to simplify the expression RCODE OPS... of type TYPE and return
2350 its value if present. */
2353 vn_nary_simplify (vn_nary_op_t nary
)
2355 if (nary
->length
> gimple_match_op::MAX_NUM_OPS
)
2357 gimple_match_op
op (gimple_match_cond::UNCOND
, nary
->opcode
,
2358 nary
->type
, nary
->length
);
2359 memcpy (op
.ops
, nary
->op
, sizeof (tree
) * nary
->length
);
2360 return vn_nary_build_or_lookup_1 (&op
, false);
2363 /* Elimination engine. */
2365 class eliminate_dom_walker
: public dom_walker
2368 eliminate_dom_walker (cdi_direction
, bitmap
);
2369 ~eliminate_dom_walker ();
2371 virtual edge
before_dom_children (basic_block
);
2372 virtual void after_dom_children (basic_block
);
2374 virtual tree
eliminate_avail (basic_block
, tree op
);
2375 virtual void eliminate_push_avail (basic_block
, tree op
);
2376 tree
eliminate_insert (basic_block
, gimple_stmt_iterator
*gsi
, tree val
);
2378 void eliminate_stmt (basic_block
, gimple_stmt_iterator
*);
2380 unsigned eliminate_cleanup (bool region_p
= false);
2383 unsigned int el_todo
;
2384 unsigned int eliminations
;
2385 unsigned int insertions
;
2387 /* SSA names that had their defs inserted by PRE if do_pre. */
2388 bitmap inserted_exprs
;
2390 /* Blocks with statements that have had their EH properties changed. */
2391 bitmap need_eh_cleanup
;
2393 /* Blocks with statements that have had their AB properties changed. */
2394 bitmap need_ab_cleanup
;
2396 /* Local state for the eliminate domwalk. */
2397 auto_vec
<gimple
*> to_remove
;
2398 auto_vec
<gimple
*> to_fixup
;
2399 auto_vec
<tree
> avail
;
2400 auto_vec
<tree
> avail_stack
;
2403 /* Adaptor to the elimination engine using RPO availability. */
2405 class rpo_elim
: public eliminate_dom_walker
2408 rpo_elim(basic_block entry_
)
2409 : eliminate_dom_walker (CDI_DOMINATORS
, NULL
), entry (entry_
),
2410 m_avail_freelist (NULL
) {}
2412 virtual tree
eliminate_avail (basic_block
, tree op
);
2414 virtual void eliminate_push_avail (basic_block
, tree
);
2417 /* Freelist of avail entries which are allocated from the vn_ssa_aux
2419 vn_avail
*m_avail_freelist
;
2422 /* Global RPO state for access from hooks. */
2423 static eliminate_dom_walker
*rpo_avail
;
2424 basic_block vn_context_bb
;
2426 /* Return true if BASE1 and BASE2 can be adjusted so they have the
2427 same address and adjust *OFFSET1 and *OFFSET2 accordingly.
2428 Otherwise return false. */
2431 adjust_offsets_for_equal_base_address (tree base1
, poly_int64
*offset1
,
2432 tree base2
, poly_int64
*offset2
)
2435 if (TREE_CODE (base1
) == MEM_REF
2436 && TREE_CODE (base2
) == MEM_REF
)
2438 if (mem_ref_offset (base1
).to_shwi (&soff
))
2440 base1
= TREE_OPERAND (base1
, 0);
2441 *offset1
+= soff
* BITS_PER_UNIT
;
2443 if (mem_ref_offset (base2
).to_shwi (&soff
))
2445 base2
= TREE_OPERAND (base2
, 0);
2446 *offset2
+= soff
* BITS_PER_UNIT
;
2448 return operand_equal_p (base1
, base2
, 0);
2450 return operand_equal_p (base1
, base2
, OEP_ADDRESS_OF
);
2453 /* Callback for walk_non_aliased_vuses. Tries to perform a lookup
2454 from the statement defining VUSE and if not successful tries to
2455 translate *REFP and VR_ through an aggregate copy at the definition
2456 of VUSE. If *DISAMBIGUATE_ONLY is true then do not perform translation
2457 of *REF and *VR. If only disambiguation was performed then
2458 *DISAMBIGUATE_ONLY is set to true. */
2461 vn_reference_lookup_3 (ao_ref
*ref
, tree vuse
, void *data_
,
2462 translate_flags
*disambiguate_only
)
2464 vn_walk_cb_data
*data
= (vn_walk_cb_data
*)data_
;
2465 vn_reference_t vr
= data
->vr
;
2466 gimple
*def_stmt
= SSA_NAME_DEF_STMT (vuse
);
2467 tree base
= ao_ref_base (ref
);
2468 HOST_WIDE_INT offseti
= 0, maxsizei
, sizei
= 0;
2469 static vec
<vn_reference_op_s
> lhs_ops
;
2471 bool lhs_ref_ok
= false;
2472 poly_int64 copy_size
;
2474 /* First try to disambiguate after value-replacing in the definitions LHS. */
2475 if (is_gimple_assign (def_stmt
))
2477 tree lhs
= gimple_assign_lhs (def_stmt
);
2478 bool valueized_anything
= false;
2479 /* Avoid re-allocation overhead. */
2480 lhs_ops
.truncate (0);
2481 basic_block saved_rpo_bb
= vn_context_bb
;
2482 vn_context_bb
= gimple_bb (def_stmt
);
2483 if (*disambiguate_only
<= TR_VALUEIZE_AND_DISAMBIGUATE
)
2485 copy_reference_ops_from_ref (lhs
, &lhs_ops
);
2486 lhs_ops
= valueize_refs_1 (lhs_ops
, &valueized_anything
, true);
2488 vn_context_bb
= saved_rpo_bb
;
2489 ao_ref_init (&lhs_ref
, lhs
);
2491 if (valueized_anything
2492 && ao_ref_init_from_vn_reference
2493 (&lhs_ref
, ao_ref_alias_set (&lhs_ref
),
2494 ao_ref_base_alias_set (&lhs_ref
), TREE_TYPE (lhs
), lhs_ops
)
2495 && !refs_may_alias_p_1 (ref
, &lhs_ref
, data
->tbaa_p
))
2497 *disambiguate_only
= TR_VALUEIZE_AND_DISAMBIGUATE
;
2501 /* Besides valueizing the LHS we can also use access-path based
2502 disambiguation on the original non-valueized ref. */
2505 && data
->orig_ref
.ref
)
2507 /* We want to use the non-valueized LHS for this, but avoid redundant
2509 ao_ref
*lref
= &lhs_ref
;
2511 if (valueized_anything
)
2513 ao_ref_init (&lref_alt
, lhs
);
2516 if (!refs_may_alias_p_1 (&data
->orig_ref
, lref
, data
->tbaa_p
))
2518 *disambiguate_only
= (valueized_anything
2519 ? TR_VALUEIZE_AND_DISAMBIGUATE
2525 /* If we reach a clobbering statement try to skip it and see if
2526 we find a VN result with exactly the same value as the
2527 possible clobber. In this case we can ignore the clobber
2528 and return the found value. */
2529 if (is_gimple_reg_type (TREE_TYPE (lhs
))
2530 && types_compatible_p (TREE_TYPE (lhs
), vr
->type
)
2531 && (ref
->ref
|| data
->orig_ref
.ref
))
2533 tree
*saved_last_vuse_ptr
= data
->last_vuse_ptr
;
2534 /* Do not update last_vuse_ptr in vn_reference_lookup_2. */
2535 data
->last_vuse_ptr
= NULL
;
2536 tree saved_vuse
= vr
->vuse
;
2537 hashval_t saved_hashcode
= vr
->hashcode
;
2538 void *res
= vn_reference_lookup_2 (ref
, gimple_vuse (def_stmt
), data
);
2539 /* Need to restore vr->vuse and vr->hashcode. */
2540 vr
->vuse
= saved_vuse
;
2541 vr
->hashcode
= saved_hashcode
;
2542 data
->last_vuse_ptr
= saved_last_vuse_ptr
;
2543 if (res
&& res
!= (void *)-1)
2545 vn_reference_t vnresult
= (vn_reference_t
) res
;
2546 tree rhs
= gimple_assign_rhs1 (def_stmt
);
2547 if (TREE_CODE (rhs
) == SSA_NAME
)
2548 rhs
= SSA_VAL (rhs
);
2549 if (vnresult
->result
2550 && operand_equal_p (vnresult
->result
, rhs
, 0)
2551 /* We have to honor our promise about union type punning
2552 and also support arbitrary overlaps with
2553 -fno-strict-aliasing. So simply resort to alignment to
2554 rule out overlaps. Do this check last because it is
2555 quite expensive compared to the hash-lookup above. */
2556 && multiple_p (get_object_alignment
2557 (ref
->ref
? ref
->ref
: data
->orig_ref
.ref
),
2559 && multiple_p (get_object_alignment (lhs
), ref
->size
))
2564 else if (*disambiguate_only
<= TR_VALUEIZE_AND_DISAMBIGUATE
2565 && gimple_call_builtin_p (def_stmt
, BUILT_IN_NORMAL
)
2566 && gimple_call_num_args (def_stmt
) <= 4)
2568 /* For builtin calls valueize its arguments and call the
2569 alias oracle again. Valueization may improve points-to
2570 info of pointers and constify size and position arguments.
2571 Originally this was motivated by PR61034 which has
2572 conditional calls to free falsely clobbering ref because
2573 of imprecise points-to info of the argument. */
2575 bool valueized_anything
= false;
2576 for (unsigned i
= 0; i
< gimple_call_num_args (def_stmt
); ++i
)
2578 oldargs
[i
] = gimple_call_arg (def_stmt
, i
);
2579 tree val
= vn_valueize (oldargs
[i
]);
2580 if (val
!= oldargs
[i
])
2582 gimple_call_set_arg (def_stmt
, i
, val
);
2583 valueized_anything
= true;
2586 if (valueized_anything
)
2588 bool res
= call_may_clobber_ref_p_1 (as_a
<gcall
*> (def_stmt
),
2590 for (unsigned i
= 0; i
< gimple_call_num_args (def_stmt
); ++i
)
2591 gimple_call_set_arg (def_stmt
, i
, oldargs
[i
]);
2594 *disambiguate_only
= TR_VALUEIZE_AND_DISAMBIGUATE
;
2600 if (*disambiguate_only
> TR_TRANSLATE
)
2603 /* If we cannot constrain the size of the reference we cannot
2604 test if anything kills it. */
2605 if (!ref
->max_size_known_p ())
2608 poly_int64 offset
= ref
->offset
;
2609 poly_int64 maxsize
= ref
->max_size
;
2611 /* def_stmt may-defs *ref. See if we can derive a value for *ref
2612 from that definition.
2614 if (is_gimple_reg_type (vr
->type
)
2615 && (gimple_call_builtin_p (def_stmt
, BUILT_IN_MEMSET
)
2616 || gimple_call_builtin_p (def_stmt
, BUILT_IN_MEMSET_CHK
))
2617 && (integer_zerop (gimple_call_arg (def_stmt
, 1))
2618 || ((TREE_CODE (gimple_call_arg (def_stmt
, 1)) == INTEGER_CST
2619 || (INTEGRAL_TYPE_P (vr
->type
) && known_eq (ref
->size
, 8)))
2621 && BITS_PER_UNIT
== 8
2622 && BYTES_BIG_ENDIAN
== WORDS_BIG_ENDIAN
2623 && offset
.is_constant (&offseti
)
2624 && ref
->size
.is_constant (&sizei
)
2625 && (offseti
% BITS_PER_UNIT
== 0
2626 || TREE_CODE (gimple_call_arg (def_stmt
, 1)) == INTEGER_CST
)))
2627 && (poly_int_tree_p (gimple_call_arg (def_stmt
, 2))
2628 || (TREE_CODE (gimple_call_arg (def_stmt
, 2)) == SSA_NAME
2629 && poly_int_tree_p (SSA_VAL (gimple_call_arg (def_stmt
, 2)))))
2630 && (TREE_CODE (gimple_call_arg (def_stmt
, 0)) == ADDR_EXPR
2631 || TREE_CODE (gimple_call_arg (def_stmt
, 0)) == SSA_NAME
))
2634 poly_int64 offset2
, size2
, maxsize2
;
2636 tree ref2
= gimple_call_arg (def_stmt
, 0);
2637 if (TREE_CODE (ref2
) == SSA_NAME
)
2639 ref2
= SSA_VAL (ref2
);
2640 if (TREE_CODE (ref2
) == SSA_NAME
2641 && (TREE_CODE (base
) != MEM_REF
2642 || TREE_OPERAND (base
, 0) != ref2
))
2644 gimple
*def_stmt
= SSA_NAME_DEF_STMT (ref2
);
2645 if (gimple_assign_single_p (def_stmt
)
2646 && gimple_assign_rhs_code (def_stmt
) == ADDR_EXPR
)
2647 ref2
= gimple_assign_rhs1 (def_stmt
);
2650 if (TREE_CODE (ref2
) == ADDR_EXPR
)
2652 ref2
= TREE_OPERAND (ref2
, 0);
2653 base2
= get_ref_base_and_extent (ref2
, &offset2
, &size2
, &maxsize2
,
2655 if (!known_size_p (maxsize2
)
2656 || !known_eq (maxsize2
, size2
)
2657 || !operand_equal_p (base
, base2
, OEP_ADDRESS_OF
))
2660 else if (TREE_CODE (ref2
) == SSA_NAME
)
2663 if (TREE_CODE (base
) != MEM_REF
2664 || !(mem_ref_offset (base
)
2665 << LOG2_BITS_PER_UNIT
).to_shwi (&soff
))
2669 if (TREE_OPERAND (base
, 0) != ref2
)
2671 gimple
*def
= SSA_NAME_DEF_STMT (ref2
);
2672 if (is_gimple_assign (def
)
2673 && gimple_assign_rhs_code (def
) == POINTER_PLUS_EXPR
2674 && gimple_assign_rhs1 (def
) == TREE_OPERAND (base
, 0)
2675 && poly_int_tree_p (gimple_assign_rhs2 (def
)))
2677 tree rhs2
= gimple_assign_rhs2 (def
);
2678 if (!(poly_offset_int::from (wi::to_poly_wide (rhs2
),
2680 << LOG2_BITS_PER_UNIT
).to_shwi (&offset2
))
2682 ref2
= gimple_assign_rhs1 (def
);
2683 if (TREE_CODE (ref2
) == SSA_NAME
)
2684 ref2
= SSA_VAL (ref2
);
2692 tree len
= gimple_call_arg (def_stmt
, 2);
2693 HOST_WIDE_INT leni
, offset2i
;
2694 if (TREE_CODE (len
) == SSA_NAME
)
2695 len
= SSA_VAL (len
);
2696 /* Sometimes the above trickery is smarter than alias analysis. Take
2697 advantage of that. */
2698 if (!ranges_maybe_overlap_p (offset
, maxsize
, offset2
,
2699 (wi::to_poly_offset (len
)
2700 << LOG2_BITS_PER_UNIT
)))
2702 if (data
->partial_defs
.is_empty ()
2703 && known_subrange_p (offset
, maxsize
, offset2
,
2704 wi::to_poly_offset (len
) << LOG2_BITS_PER_UNIT
))
2707 if (integer_zerop (gimple_call_arg (def_stmt
, 1)))
2708 val
= build_zero_cst (vr
->type
);
2709 else if (INTEGRAL_TYPE_P (vr
->type
)
2710 && known_eq (ref
->size
, 8)
2711 && offseti
% BITS_PER_UNIT
== 0)
2713 gimple_match_op
res_op (gimple_match_cond::UNCOND
, NOP_EXPR
,
2714 vr
->type
, gimple_call_arg (def_stmt
, 1));
2715 val
= vn_nary_build_or_lookup (&res_op
);
2717 || (TREE_CODE (val
) == SSA_NAME
2718 && SSA_NAME_OCCURS_IN_ABNORMAL_PHI (val
)))
2723 unsigned buflen
= TREE_INT_CST_LOW (TYPE_SIZE_UNIT (vr
->type
)) + 1;
2724 if (INTEGRAL_TYPE_P (vr
->type
))
2725 buflen
= GET_MODE_SIZE (SCALAR_INT_TYPE_MODE (vr
->type
)) + 1;
2726 unsigned char *buf
= XALLOCAVEC (unsigned char, buflen
);
2727 memset (buf
, TREE_INT_CST_LOW (gimple_call_arg (def_stmt
, 1)),
2729 if (BYTES_BIG_ENDIAN
)
2732 = (((unsigned HOST_WIDE_INT
) offseti
+ sizei
)
2736 shift_bytes_in_array_right (buf
, buflen
,
2737 BITS_PER_UNIT
- amnt
);
2742 else if (offseti
% BITS_PER_UNIT
!= 0)
2745 = BITS_PER_UNIT
- ((unsigned HOST_WIDE_INT
) offseti
2747 shift_bytes_in_array_left (buf
, buflen
, amnt
);
2751 val
= native_interpret_expr (vr
->type
, buf
, buflen
);
2755 return data
->finish (0, 0, val
);
2757 /* For now handle clearing memory with partial defs. */
2758 else if (known_eq (ref
->size
, maxsize
)
2759 && integer_zerop (gimple_call_arg (def_stmt
, 1))
2760 && tree_fits_poly_int64_p (len
)
2761 && tree_to_poly_int64 (len
).is_constant (&leni
)
2762 && leni
<= INTTYPE_MAXIMUM (HOST_WIDE_INT
) / BITS_PER_UNIT
2763 && offset
.is_constant (&offseti
)
2764 && offset2
.is_constant (&offset2i
)
2765 && maxsize
.is_constant (&maxsizei
)
2766 && ranges_known_overlap_p (offseti
, maxsizei
, offset2i
,
2767 leni
<< LOG2_BITS_PER_UNIT
))
2770 pd
.rhs
= build_constructor (NULL_TREE
, NULL
);
2771 pd
.offset
= offset2i
;
2772 pd
.size
= leni
<< LOG2_BITS_PER_UNIT
;
2773 return data
->push_partial_def (pd
, 0, 0, offseti
, maxsizei
);
2777 /* 2) Assignment from an empty CONSTRUCTOR. */
2778 else if (is_gimple_reg_type (vr
->type
)
2779 && gimple_assign_single_p (def_stmt
)
2780 && gimple_assign_rhs_code (def_stmt
) == CONSTRUCTOR
2781 && CONSTRUCTOR_NELTS (gimple_assign_rhs1 (def_stmt
)) == 0)
2784 poly_int64 offset2
, size2
, maxsize2
;
2785 HOST_WIDE_INT offset2i
, size2i
;
2786 gcc_assert (lhs_ref_ok
);
2787 base2
= ao_ref_base (&lhs_ref
);
2788 offset2
= lhs_ref
.offset
;
2789 size2
= lhs_ref
.size
;
2790 maxsize2
= lhs_ref
.max_size
;
2791 if (known_size_p (maxsize2
)
2792 && known_eq (maxsize2
, size2
)
2793 && adjust_offsets_for_equal_base_address (base
, &offset
,
2796 if (data
->partial_defs
.is_empty ()
2797 && known_subrange_p (offset
, maxsize
, offset2
, size2
))
2799 /* While technically undefined behavior do not optimize
2800 a full read from a clobber. */
2801 if (gimple_clobber_p (def_stmt
))
2803 tree val
= build_zero_cst (vr
->type
);
2804 return data
->finish (ao_ref_alias_set (&lhs_ref
),
2805 ao_ref_base_alias_set (&lhs_ref
), val
);
2807 else if (known_eq (ref
->size
, maxsize
)
2808 && maxsize
.is_constant (&maxsizei
)
2809 && offset
.is_constant (&offseti
)
2810 && offset2
.is_constant (&offset2i
)
2811 && size2
.is_constant (&size2i
)
2812 && ranges_known_overlap_p (offseti
, maxsizei
,
2815 /* Let clobbers be consumed by the partial-def tracker
2816 which can choose to ignore them if they are shadowed
2819 pd
.rhs
= gimple_assign_rhs1 (def_stmt
);
2820 pd
.offset
= offset2i
;
2822 return data
->push_partial_def (pd
, ao_ref_alias_set (&lhs_ref
),
2823 ao_ref_base_alias_set (&lhs_ref
),
2829 /* 3) Assignment from a constant. We can use folds native encode/interpret
2830 routines to extract the assigned bits. */
2831 else if (known_eq (ref
->size
, maxsize
)
2832 && is_gimple_reg_type (vr
->type
)
2833 && !contains_storage_order_barrier_p (vr
->operands
)
2834 && gimple_assign_single_p (def_stmt
)
2836 && BITS_PER_UNIT
== 8
2837 && BYTES_BIG_ENDIAN
== WORDS_BIG_ENDIAN
2838 /* native_encode and native_decode operate on arrays of bytes
2839 and so fundamentally need a compile-time size and offset. */
2840 && maxsize
.is_constant (&maxsizei
)
2841 && offset
.is_constant (&offseti
)
2842 && (is_gimple_min_invariant (gimple_assign_rhs1 (def_stmt
))
2843 || (TREE_CODE (gimple_assign_rhs1 (def_stmt
)) == SSA_NAME
2844 && is_gimple_min_invariant (SSA_VAL (gimple_assign_rhs1 (def_stmt
))))))
2846 tree lhs
= gimple_assign_lhs (def_stmt
);
2848 poly_int64 offset2
, size2
, maxsize2
;
2849 HOST_WIDE_INT offset2i
, size2i
;
2851 gcc_assert (lhs_ref_ok
);
2852 base2
= ao_ref_base (&lhs_ref
);
2853 offset2
= lhs_ref
.offset
;
2854 size2
= lhs_ref
.size
;
2855 maxsize2
= lhs_ref
.max_size
;
2856 reverse
= reverse_storage_order_for_component_p (lhs
);
2859 && !storage_order_barrier_p (lhs
)
2860 && known_eq (maxsize2
, size2
)
2861 && adjust_offsets_for_equal_base_address (base
, &offset
,
2863 && offset
.is_constant (&offseti
)
2864 && offset2
.is_constant (&offset2i
)
2865 && size2
.is_constant (&size2i
))
2867 if (data
->partial_defs
.is_empty ()
2868 && known_subrange_p (offseti
, maxsizei
, offset2
, size2
))
2870 /* We support up to 512-bit values (for V8DFmode). */
2871 unsigned char buffer
[65];
2874 tree rhs
= gimple_assign_rhs1 (def_stmt
);
2875 if (TREE_CODE (rhs
) == SSA_NAME
)
2876 rhs
= SSA_VAL (rhs
);
2877 len
= native_encode_expr (rhs
,
2878 buffer
, sizeof (buffer
) - 1,
2879 (offseti
- offset2i
) / BITS_PER_UNIT
);
2880 if (len
> 0 && len
* BITS_PER_UNIT
>= maxsizei
)
2882 tree type
= vr
->type
;
2883 unsigned char *buf
= buffer
;
2884 unsigned int amnt
= 0;
2885 /* Make sure to interpret in a type that has a range
2886 covering the whole access size. */
2887 if (INTEGRAL_TYPE_P (vr
->type
)
2888 && maxsizei
!= TYPE_PRECISION (vr
->type
))
2889 type
= build_nonstandard_integer_type (maxsizei
,
2890 TYPE_UNSIGNED (type
));
2891 if (BYTES_BIG_ENDIAN
)
2893 /* For big-endian native_encode_expr stored the rhs
2894 such that the LSB of it is the LSB of buffer[len - 1].
2895 That bit is stored into memory at position
2896 offset2 + size2 - 1, i.e. in byte
2897 base + (offset2 + size2 - 1) / BITS_PER_UNIT.
2898 E.g. for offset2 1 and size2 14, rhs -1 and memory
2899 previously cleared that is:
2902 Now, if we want to extract offset 2 and size 12 from
2903 it using native_interpret_expr (which actually works
2904 for integral bitfield types in terms of byte size of
2905 the mode), the native_encode_expr stored the value
2908 and returned len 2 (the X bits are outside of
2910 Let sz be maxsize / BITS_PER_UNIT if not extracting
2911 a bitfield, and GET_MODE_SIZE otherwise.
2912 We need to align the LSB of the value we want to
2913 extract as the LSB of buf[sz - 1].
2914 The LSB from memory we need to read is at position
2915 offset + maxsize - 1. */
2916 HOST_WIDE_INT sz
= maxsizei
/ BITS_PER_UNIT
;
2917 if (INTEGRAL_TYPE_P (type
))
2918 sz
= GET_MODE_SIZE (SCALAR_INT_TYPE_MODE (type
));
2919 amnt
= ((unsigned HOST_WIDE_INT
) offset2i
+ size2i
2920 - offseti
- maxsizei
) % BITS_PER_UNIT
;
2922 shift_bytes_in_array_right (buffer
, len
, amnt
);
2923 amnt
= ((unsigned HOST_WIDE_INT
) offset2i
+ size2i
2924 - offseti
- maxsizei
- amnt
) / BITS_PER_UNIT
;
2925 if ((unsigned HOST_WIDE_INT
) sz
+ amnt
> (unsigned) len
)
2929 buf
= buffer
+ len
- sz
- amnt
;
2930 len
-= (buf
- buffer
);
2935 amnt
= ((unsigned HOST_WIDE_INT
) offset2i
2936 - offseti
) % BITS_PER_UNIT
;
2940 shift_bytes_in_array_left (buffer
, len
+ 1, amnt
);
2944 tree val
= native_interpret_expr (type
, buf
, len
);
2945 /* If we chop off bits because the types precision doesn't
2946 match the memory access size this is ok when optimizing
2947 reads but not when called from the DSE code during
2950 && type
!= vr
->type
)
2952 if (! int_fits_type_p (val
, vr
->type
))
2955 val
= fold_convert (vr
->type
, val
);
2959 return data
->finish (ao_ref_alias_set (&lhs_ref
),
2960 ao_ref_base_alias_set (&lhs_ref
), val
);
2963 else if (ranges_known_overlap_p (offseti
, maxsizei
, offset2i
,
2967 tree rhs
= gimple_assign_rhs1 (def_stmt
);
2968 if (TREE_CODE (rhs
) == SSA_NAME
)
2969 rhs
= SSA_VAL (rhs
);
2971 pd
.offset
= offset2i
;
2973 return data
->push_partial_def (pd
, ao_ref_alias_set (&lhs_ref
),
2974 ao_ref_base_alias_set (&lhs_ref
),
2980 /* 4) Assignment from an SSA name which definition we may be able
2981 to access pieces from or we can combine to a larger entity. */
2982 else if (known_eq (ref
->size
, maxsize
)
2983 && is_gimple_reg_type (vr
->type
)
2984 && !contains_storage_order_barrier_p (vr
->operands
)
2985 && gimple_assign_single_p (def_stmt
)
2986 && TREE_CODE (gimple_assign_rhs1 (def_stmt
)) == SSA_NAME
)
2988 tree lhs
= gimple_assign_lhs (def_stmt
);
2990 poly_int64 offset2
, size2
, maxsize2
;
2991 HOST_WIDE_INT offset2i
, size2i
, offseti
;
2993 gcc_assert (lhs_ref_ok
);
2994 base2
= ao_ref_base (&lhs_ref
);
2995 offset2
= lhs_ref
.offset
;
2996 size2
= lhs_ref
.size
;
2997 maxsize2
= lhs_ref
.max_size
;
2998 reverse
= reverse_storage_order_for_component_p (lhs
);
2999 tree def_rhs
= gimple_assign_rhs1 (def_stmt
);
3001 && !storage_order_barrier_p (lhs
)
3002 && known_size_p (maxsize2
)
3003 && known_eq (maxsize2
, size2
)
3004 && adjust_offsets_for_equal_base_address (base
, &offset
,
3007 if (data
->partial_defs
.is_empty ()
3008 && known_subrange_p (offset
, maxsize
, offset2
, size2
)
3009 /* ??? We can't handle bitfield precision extracts without
3010 either using an alternate type for the BIT_FIELD_REF and
3011 then doing a conversion or possibly adjusting the offset
3012 according to endianness. */
3013 && (! INTEGRAL_TYPE_P (vr
->type
)
3014 || known_eq (ref
->size
, TYPE_PRECISION (vr
->type
)))
3015 && multiple_p (ref
->size
, BITS_PER_UNIT
))
3017 tree val
= NULL_TREE
;
3018 if (! INTEGRAL_TYPE_P (TREE_TYPE (def_rhs
))
3019 || type_has_mode_precision_p (TREE_TYPE (def_rhs
)))
3021 gimple_match_op
op (gimple_match_cond::UNCOND
,
3022 BIT_FIELD_REF
, vr
->type
,
3024 bitsize_int (ref
->size
),
3025 bitsize_int (offset
- offset2
));
3026 val
= vn_nary_build_or_lookup (&op
);
3028 else if (known_eq (ref
->size
, size2
))
3030 gimple_match_op
op (gimple_match_cond::UNCOND
,
3031 VIEW_CONVERT_EXPR
, vr
->type
,
3033 val
= vn_nary_build_or_lookup (&op
);
3036 && (TREE_CODE (val
) != SSA_NAME
3037 || ! SSA_NAME_OCCURS_IN_ABNORMAL_PHI (val
)))
3038 return data
->finish (ao_ref_alias_set (&lhs_ref
),
3039 ao_ref_base_alias_set (&lhs_ref
), val
);
3041 else if (maxsize
.is_constant (&maxsizei
)
3042 && offset
.is_constant (&offseti
)
3043 && offset2
.is_constant (&offset2i
)
3044 && size2
.is_constant (&size2i
)
3045 && ranges_known_overlap_p (offset
, maxsize
, offset2
, size2
))
3048 pd
.rhs
= SSA_VAL (def_rhs
);
3049 pd
.offset
= offset2i
;
3051 return data
->push_partial_def (pd
, ao_ref_alias_set (&lhs_ref
),
3052 ao_ref_base_alias_set (&lhs_ref
),
3058 /* 5) For aggregate copies translate the reference through them if
3059 the copy kills ref. */
3060 else if (data
->vn_walk_kind
== VN_WALKREWRITE
3061 && gimple_assign_single_p (def_stmt
)
3062 && (DECL_P (gimple_assign_rhs1 (def_stmt
))
3063 || TREE_CODE (gimple_assign_rhs1 (def_stmt
)) == MEM_REF
3064 || handled_component_p (gimple_assign_rhs1 (def_stmt
))))
3068 auto_vec
<vn_reference_op_s
> rhs
;
3069 vn_reference_op_t vro
;
3072 gcc_assert (lhs_ref_ok
);
3074 /* See if the assignment kills REF. */
3075 base2
= ao_ref_base (&lhs_ref
);
3076 if (!lhs_ref
.max_size_known_p ()
3078 && (TREE_CODE (base
) != MEM_REF
3079 || TREE_CODE (base2
) != MEM_REF
3080 || TREE_OPERAND (base
, 0) != TREE_OPERAND (base2
, 0)
3081 || !tree_int_cst_equal (TREE_OPERAND (base
, 1),
3082 TREE_OPERAND (base2
, 1))))
3083 || !stmt_kills_ref_p (def_stmt
, ref
))
3086 /* Find the common base of ref and the lhs. lhs_ops already
3087 contains valueized operands for the lhs. */
3088 i
= vr
->operands
.length () - 1;
3089 j
= lhs_ops
.length () - 1;
3090 while (j
>= 0 && i
>= 0
3091 && vn_reference_op_eq (&vr
->operands
[i
], &lhs_ops
[j
]))
3097 /* ??? The innermost op should always be a MEM_REF and we already
3098 checked that the assignment to the lhs kills vr. Thus for
3099 aggregate copies using char[] types the vn_reference_op_eq
3100 may fail when comparing types for compatibility. But we really
3101 don't care here - further lookups with the rewritten operands
3102 will simply fail if we messed up types too badly. */
3103 poly_int64 extra_off
= 0;
3104 if (j
== 0 && i
>= 0
3105 && lhs_ops
[0].opcode
== MEM_REF
3106 && maybe_ne (lhs_ops
[0].off
, -1))
3108 if (known_eq (lhs_ops
[0].off
, vr
->operands
[i
].off
))
3110 else if (vr
->operands
[i
].opcode
== MEM_REF
3111 && maybe_ne (vr
->operands
[i
].off
, -1))
3113 extra_off
= vr
->operands
[i
].off
- lhs_ops
[0].off
;
3118 /* i now points to the first additional op.
3119 ??? LHS may not be completely contained in VR, one or more
3120 VIEW_CONVERT_EXPRs could be in its way. We could at least
3121 try handling outermost VIEW_CONVERT_EXPRs. */
3125 /* Punt if the additional ops contain a storage order barrier. */
3126 for (k
= i
; k
>= 0; k
--)
3128 vro
= &vr
->operands
[k
];
3129 if (vro
->opcode
== VIEW_CONVERT_EXPR
&& vro
->reverse
)
3133 /* Now re-write REF to be based on the rhs of the assignment. */
3134 tree rhs1
= gimple_assign_rhs1 (def_stmt
);
3135 copy_reference_ops_from_ref (rhs1
, &rhs
);
3137 /* Apply an extra offset to the inner MEM_REF of the RHS. */
3138 if (maybe_ne (extra_off
, 0))
3140 if (rhs
.length () < 2)
3142 int ix
= rhs
.length () - 2;
3143 if (rhs
[ix
].opcode
!= MEM_REF
3144 || known_eq (rhs
[ix
].off
, -1))
3146 rhs
[ix
].off
+= extra_off
;
3147 rhs
[ix
].op0
= int_const_binop (PLUS_EXPR
, rhs
[ix
].op0
,
3148 build_int_cst (TREE_TYPE (rhs
[ix
].op0
),
3152 /* Save the operands since we need to use the original ones for
3153 the hash entry we use. */
3154 if (!data
->saved_operands
.exists ())
3155 data
->saved_operands
= vr
->operands
.copy ();
3157 /* We need to pre-pend vr->operands[0..i] to rhs. */
3158 vec
<vn_reference_op_s
> old
= vr
->operands
;
3159 if (i
+ 1 + rhs
.length () > vr
->operands
.length ())
3160 vr
->operands
.safe_grow (i
+ 1 + rhs
.length (), true);
3162 vr
->operands
.truncate (i
+ 1 + rhs
.length ());
3163 FOR_EACH_VEC_ELT (rhs
, j
, vro
)
3164 vr
->operands
[i
+ 1 + j
] = *vro
;
3165 vr
->operands
= valueize_refs (vr
->operands
);
3166 if (old
== shared_lookup_references
)
3167 shared_lookup_references
= vr
->operands
;
3168 vr
->hashcode
= vn_reference_compute_hash (vr
);
3170 /* Try folding the new reference to a constant. */
3171 tree val
= fully_constant_vn_reference_p (vr
);
3174 if (data
->partial_defs
.is_empty ())
3175 return data
->finish (ao_ref_alias_set (&lhs_ref
),
3176 ao_ref_base_alias_set (&lhs_ref
), val
);
3177 /* This is the only interesting case for partial-def handling
3178 coming from targets that like to gimplify init-ctors as
3179 aggregate copies from constant data like aarch64 for
3181 if (maxsize
.is_constant (&maxsizei
) && known_eq (ref
->size
, maxsize
))
3187 return data
->push_partial_def (pd
, ao_ref_alias_set (&lhs_ref
),
3188 ao_ref_base_alias_set (&lhs_ref
),
3193 /* Continuing with partial defs isn't easily possible here, we
3194 have to find a full def from further lookups from here. Probably
3195 not worth the special-casing everywhere. */
3196 if (!data
->partial_defs
.is_empty ())
3199 /* Adjust *ref from the new operands. */
3201 ao_ref_init (&rhs1_ref
, rhs1
);
3202 if (!ao_ref_init_from_vn_reference (&r
, ao_ref_alias_set (&rhs1_ref
),
3203 ao_ref_base_alias_set (&rhs1_ref
),
3204 vr
->type
, vr
->operands
))
3206 /* This can happen with bitfields. */
3207 if (maybe_ne (ref
->size
, r
.size
))
3211 /* Do not update last seen VUSE after translating. */
3212 data
->last_vuse_ptr
= NULL
;
3213 /* Invalidate the original access path since it now contains
3215 data
->orig_ref
.ref
= NULL_TREE
;
3216 /* Use the alias-set of this LHS for recording an eventual result. */
3217 if (data
->first_set
== -2)
3219 data
->first_set
= ao_ref_alias_set (&lhs_ref
);
3220 data
->first_base_set
= ao_ref_base_alias_set (&lhs_ref
);
3223 /* Keep looking for the adjusted *REF / VR pair. */
3227 /* 6) For memcpy copies translate the reference through them if the copy
3228 kills ref. But we cannot (easily) do this translation if the memcpy is
3229 a storage order barrier, i.e. is equivalent to a VIEW_CONVERT_EXPR that
3230 can modify the storage order of objects (see storage_order_barrier_p). */
3231 else if (data
->vn_walk_kind
== VN_WALKREWRITE
3232 && is_gimple_reg_type (vr
->type
)
3233 /* ??? Handle BCOPY as well. */
3234 && (gimple_call_builtin_p (def_stmt
, BUILT_IN_MEMCPY
)
3235 || gimple_call_builtin_p (def_stmt
, BUILT_IN_MEMCPY_CHK
)
3236 || gimple_call_builtin_p (def_stmt
, BUILT_IN_MEMPCPY
)
3237 || gimple_call_builtin_p (def_stmt
, BUILT_IN_MEMPCPY_CHK
)
3238 || gimple_call_builtin_p (def_stmt
, BUILT_IN_MEMMOVE
)
3239 || gimple_call_builtin_p (def_stmt
, BUILT_IN_MEMMOVE_CHK
))
3240 && (TREE_CODE (gimple_call_arg (def_stmt
, 0)) == ADDR_EXPR
3241 || TREE_CODE (gimple_call_arg (def_stmt
, 0)) == SSA_NAME
)
3242 && (TREE_CODE (gimple_call_arg (def_stmt
, 1)) == ADDR_EXPR
3243 || TREE_CODE (gimple_call_arg (def_stmt
, 1)) == SSA_NAME
)
3244 && (poly_int_tree_p (gimple_call_arg (def_stmt
, 2), ©_size
)
3245 || (TREE_CODE (gimple_call_arg (def_stmt
, 2)) == SSA_NAME
3246 && poly_int_tree_p (SSA_VAL (gimple_call_arg (def_stmt
, 2)),
3248 /* Handling this is more complicated, give up for now. */
3249 && data
->partial_defs
.is_empty ())
3253 poly_int64 rhs_offset
, lhs_offset
;
3254 vn_reference_op_s op
;
3255 poly_uint64 mem_offset
;
3256 poly_int64 at
, byte_maxsize
;
3258 /* Only handle non-variable, addressable refs. */
3259 if (maybe_ne (ref
->size
, maxsize
)
3260 || !multiple_p (offset
, BITS_PER_UNIT
, &at
)
3261 || !multiple_p (maxsize
, BITS_PER_UNIT
, &byte_maxsize
))
3264 /* Extract a pointer base and an offset for the destination. */
3265 lhs
= gimple_call_arg (def_stmt
, 0);
3267 if (TREE_CODE (lhs
) == SSA_NAME
)
3269 lhs
= vn_valueize (lhs
);
3270 if (TREE_CODE (lhs
) == SSA_NAME
)
3272 gimple
*def_stmt
= SSA_NAME_DEF_STMT (lhs
);
3273 if (gimple_assign_single_p (def_stmt
)
3274 && gimple_assign_rhs_code (def_stmt
) == ADDR_EXPR
)
3275 lhs
= gimple_assign_rhs1 (def_stmt
);
3278 if (TREE_CODE (lhs
) == ADDR_EXPR
)
3280 if (AGGREGATE_TYPE_P (TREE_TYPE (TREE_TYPE (lhs
)))
3281 && TYPE_REVERSE_STORAGE_ORDER (TREE_TYPE (TREE_TYPE (lhs
))))
3283 tree tem
= get_addr_base_and_unit_offset (TREE_OPERAND (lhs
, 0),
3287 if (TREE_CODE (tem
) == MEM_REF
3288 && poly_int_tree_p (TREE_OPERAND (tem
, 1), &mem_offset
))
3290 lhs
= TREE_OPERAND (tem
, 0);
3291 if (TREE_CODE (lhs
) == SSA_NAME
)
3292 lhs
= vn_valueize (lhs
);
3293 lhs_offset
+= mem_offset
;
3295 else if (DECL_P (tem
))
3296 lhs
= build_fold_addr_expr (tem
);
3300 if (TREE_CODE (lhs
) != SSA_NAME
3301 && TREE_CODE (lhs
) != ADDR_EXPR
)
3304 /* Extract a pointer base and an offset for the source. */
3305 rhs
= gimple_call_arg (def_stmt
, 1);
3307 if (TREE_CODE (rhs
) == SSA_NAME
)
3308 rhs
= vn_valueize (rhs
);
3309 if (TREE_CODE (rhs
) == ADDR_EXPR
)
3311 if (AGGREGATE_TYPE_P (TREE_TYPE (TREE_TYPE (rhs
)))
3312 && TYPE_REVERSE_STORAGE_ORDER (TREE_TYPE (TREE_TYPE (rhs
))))
3314 tree tem
= get_addr_base_and_unit_offset (TREE_OPERAND (rhs
, 0),
3318 if (TREE_CODE (tem
) == MEM_REF
3319 && poly_int_tree_p (TREE_OPERAND (tem
, 1), &mem_offset
))
3321 rhs
= TREE_OPERAND (tem
, 0);
3322 rhs_offset
+= mem_offset
;
3324 else if (DECL_P (tem
)
3325 || TREE_CODE (tem
) == STRING_CST
)
3326 rhs
= build_fold_addr_expr (tem
);
3330 if (TREE_CODE (rhs
) == SSA_NAME
)
3331 rhs
= SSA_VAL (rhs
);
3332 else if (TREE_CODE (rhs
) != ADDR_EXPR
)
3335 /* The bases of the destination and the references have to agree. */
3336 if (TREE_CODE (base
) == MEM_REF
)
3338 if (TREE_OPERAND (base
, 0) != lhs
3339 || !poly_int_tree_p (TREE_OPERAND (base
, 1), &mem_offset
))
3343 else if (!DECL_P (base
)
3344 || TREE_CODE (lhs
) != ADDR_EXPR
3345 || TREE_OPERAND (lhs
, 0) != base
)
3348 /* If the access is completely outside of the memcpy destination
3349 area there is no aliasing. */
3350 if (!ranges_maybe_overlap_p (lhs_offset
, copy_size
, at
, byte_maxsize
))
3352 /* And the access has to be contained within the memcpy destination. */
3353 if (!known_subrange_p (at
, byte_maxsize
, lhs_offset
, copy_size
))
3356 /* Save the operands since we need to use the original ones for
3357 the hash entry we use. */
3358 if (!data
->saved_operands
.exists ())
3359 data
->saved_operands
= vr
->operands
.copy ();
3361 /* Make room for 2 operands in the new reference. */
3362 if (vr
->operands
.length () < 2)
3364 vec
<vn_reference_op_s
> old
= vr
->operands
;
3365 vr
->operands
.safe_grow_cleared (2, true);
3366 if (old
== shared_lookup_references
)
3367 shared_lookup_references
= vr
->operands
;
3370 vr
->operands
.truncate (2);
3372 /* The looked-through reference is a simple MEM_REF. */
3373 memset (&op
, 0, sizeof (op
));
3375 op
.opcode
= MEM_REF
;
3376 op
.op0
= build_int_cst (ptr_type_node
, at
- lhs_offset
+ rhs_offset
);
3377 op
.off
= at
- lhs_offset
+ rhs_offset
;
3378 vr
->operands
[0] = op
;
3379 op
.type
= TREE_TYPE (rhs
);
3380 op
.opcode
= TREE_CODE (rhs
);
3383 vr
->operands
[1] = op
;
3384 vr
->hashcode
= vn_reference_compute_hash (vr
);
3386 /* Try folding the new reference to a constant. */
3387 tree val
= fully_constant_vn_reference_p (vr
);
3389 return data
->finish (0, 0, val
);
3391 /* Adjust *ref from the new operands. */
3392 if (!ao_ref_init_from_vn_reference (&r
, 0, 0, vr
->type
, vr
->operands
))
3394 /* This can happen with bitfields. */
3395 if (maybe_ne (ref
->size
, r
.size
))
3399 /* Do not update last seen VUSE after translating. */
3400 data
->last_vuse_ptr
= NULL
;
3401 /* Invalidate the original access path since it now contains
3403 data
->orig_ref
.ref
= NULL_TREE
;
3404 /* Use the alias-set of this stmt for recording an eventual result. */
3405 if (data
->first_set
== -2)
3407 data
->first_set
= 0;
3408 data
->first_base_set
= 0;
3411 /* Keep looking for the adjusted *REF / VR pair. */
3415 /* Bail out and stop walking. */
3419 /* Return a reference op vector from OP that can be used for
3420 vn_reference_lookup_pieces. The caller is responsible for releasing
3423 vec
<vn_reference_op_s
>
3424 vn_reference_operands_for_lookup (tree op
)
3427 return valueize_shared_reference_ops_from_ref (op
, &valueized
).copy ();
3430 /* Lookup a reference operation by it's parts, in the current hash table.
3431 Returns the resulting value number if it exists in the hash table,
3432 NULL_TREE otherwise. VNRESULT will be filled in with the actual
3433 vn_reference_t stored in the hashtable if something is found. */
3436 vn_reference_lookup_pieces (tree vuse
, alias_set_type set
,
3437 alias_set_type base_set
, tree type
,
3438 vec
<vn_reference_op_s
> operands
,
3439 vn_reference_t
*vnresult
, vn_lookup_kind kind
)
3441 struct vn_reference_s vr1
;
3449 vr1
.vuse
= vuse_ssa_val (vuse
);
3450 shared_lookup_references
.truncate (0);
3451 shared_lookup_references
.safe_grow (operands
.length (), true);
3452 memcpy (shared_lookup_references
.address (),
3453 operands
.address (),
3454 sizeof (vn_reference_op_s
)
3455 * operands
.length ());
3456 vr1
.operands
= operands
= shared_lookup_references
3457 = valueize_refs (shared_lookup_references
);
3460 vr1
.base_set
= base_set
;
3461 vr1
.hashcode
= vn_reference_compute_hash (&vr1
);
3462 if ((cst
= fully_constant_vn_reference_p (&vr1
)))
3465 vn_reference_lookup_1 (&vr1
, vnresult
);
3467 && kind
!= VN_NOWALK
3471 unsigned limit
= param_sccvn_max_alias_queries_per_access
;
3472 vn_walk_cb_data
data (&vr1
, NULL_TREE
, NULL
, kind
, true, NULL_TREE
);
3473 if (ao_ref_init_from_vn_reference (&r
, set
, base_set
, type
,
3477 walk_non_aliased_vuses (&r
, vr1
.vuse
, true, vn_reference_lookup_2
,
3478 vn_reference_lookup_3
, vuse_valueize
,
3480 gcc_checking_assert (vr1
.operands
== shared_lookup_references
);
3484 return (*vnresult
)->result
;
3489 /* Lookup OP in the current hash table, and return the resulting value
3490 number if it exists in the hash table. Return NULL_TREE if it does
3491 not exist in the hash table or if the result field of the structure
3492 was NULL.. VNRESULT will be filled in with the vn_reference_t
3493 stored in the hashtable if one exists. When TBAA_P is false assume
3494 we are looking up a store and treat it as having alias-set zero.
3495 *LAST_VUSE_PTR will be updated with the VUSE the value lookup succeeded.
3496 MASK is either NULL_TREE, or can be an INTEGER_CST if the result of the
3497 load is bitwise anded with MASK and so we are only interested in a subset
3498 of the bits and can ignore if the other bits are uninitialized or
3499 not initialized with constants. */
3502 vn_reference_lookup (tree op
, tree vuse
, vn_lookup_kind kind
,
3503 vn_reference_t
*vnresult
, bool tbaa_p
,
3504 tree
*last_vuse_ptr
, tree mask
)
3506 vec
<vn_reference_op_s
> operands
;
3507 struct vn_reference_s vr1
;
3508 bool valuezied_anything
;
3513 vr1
.vuse
= vuse_ssa_val (vuse
);
3514 vr1
.operands
= operands
3515 = valueize_shared_reference_ops_from_ref (op
, &valuezied_anything
);
3516 vr1
.type
= TREE_TYPE (op
);
3518 ao_ref_init (&op_ref
, op
);
3519 vr1
.set
= ao_ref_alias_set (&op_ref
);
3520 vr1
.base_set
= ao_ref_base_alias_set (&op_ref
);
3521 vr1
.hashcode
= vn_reference_compute_hash (&vr1
);
3522 if (mask
== NULL_TREE
)
3523 if (tree cst
= fully_constant_vn_reference_p (&vr1
))
3526 if (kind
!= VN_NOWALK
&& vr1
.vuse
)
3528 vn_reference_t wvnresult
;
3530 unsigned limit
= param_sccvn_max_alias_queries_per_access
;
3531 /* Make sure to use a valueized reference if we valueized anything.
3532 Otherwise preserve the full reference for advanced TBAA. */
3533 if (!valuezied_anything
3534 || !ao_ref_init_from_vn_reference (&r
, vr1
.set
, vr1
.base_set
,
3535 vr1
.type
, vr1
.operands
))
3536 ao_ref_init (&r
, op
);
3537 vn_walk_cb_data
data (&vr1
, r
.ref
? NULL_TREE
: op
,
3538 last_vuse_ptr
, kind
, tbaa_p
, mask
);
3542 walk_non_aliased_vuses (&r
, vr1
.vuse
, tbaa_p
, vn_reference_lookup_2
,
3543 vn_reference_lookup_3
, vuse_valueize
, limit
,
3545 gcc_checking_assert (vr1
.operands
== shared_lookup_references
);
3548 gcc_assert (mask
== NULL_TREE
);
3550 *vnresult
= wvnresult
;
3551 return wvnresult
->result
;
3554 return data
.masked_result
;
3560 *last_vuse_ptr
= vr1
.vuse
;
3563 return vn_reference_lookup_1 (&vr1
, vnresult
);
3566 /* Lookup CALL in the current hash table and return the entry in
3567 *VNRESULT if found. Populates *VR for the hashtable lookup. */
3570 vn_reference_lookup_call (gcall
*call
, vn_reference_t
*vnresult
,
3576 tree vuse
= gimple_vuse (call
);
3578 vr
->vuse
= vuse
? SSA_VAL (vuse
) : NULL_TREE
;
3579 vr
->operands
= valueize_shared_reference_ops_from_call (call
);
3580 vr
->type
= gimple_expr_type (call
);
3584 vr
->hashcode
= vn_reference_compute_hash (vr
);
3585 vn_reference_lookup_1 (vr
, vnresult
);
3588 /* Insert OP into the current hash table with a value number of RESULT. */
3591 vn_reference_insert (tree op
, tree result
, tree vuse
, tree vdef
)
3593 vn_reference_s
**slot
;
3597 vr1
= XOBNEW (&vn_tables_obstack
, vn_reference_s
);
3598 if (TREE_CODE (result
) == SSA_NAME
)
3599 vr1
->value_id
= VN_INFO (result
)->value_id
;
3601 vr1
->value_id
= get_or_alloc_constant_value_id (result
);
3602 vr1
->vuse
= vuse_ssa_val (vuse
);
3603 vr1
->operands
= valueize_shared_reference_ops_from_ref (op
, &tem
).copy ();
3604 vr1
->type
= TREE_TYPE (op
);
3605 vr1
->punned
= false;
3607 ao_ref_init (&op_ref
, op
);
3608 vr1
->set
= ao_ref_alias_set (&op_ref
);
3609 vr1
->base_set
= ao_ref_base_alias_set (&op_ref
);
3610 vr1
->hashcode
= vn_reference_compute_hash (vr1
);
3611 vr1
->result
= TREE_CODE (result
) == SSA_NAME
? SSA_VAL (result
) : result
;
3612 vr1
->result_vdef
= vdef
;
3614 slot
= valid_info
->references
->find_slot_with_hash (vr1
, vr1
->hashcode
,
3617 /* Because IL walking on reference lookup can end up visiting
3618 a def that is only to be visited later in iteration order
3619 when we are about to make an irreducible region reducible
3620 the def can be effectively processed and its ref being inserted
3621 by vn_reference_lookup_3 already. So we cannot assert (!*slot)
3622 but save a lookup if we deal with already inserted refs here. */
3625 /* We cannot assert that we have the same value either because
3626 when disentangling an irreducible region we may end up visiting
3627 a use before the corresponding def. That's a missed optimization
3628 only though. See gcc.dg/tree-ssa/pr87126.c for example. */
3629 if (dump_file
&& (dump_flags
& TDF_DETAILS
)
3630 && !operand_equal_p ((*slot
)->result
, vr1
->result
, 0))
3632 fprintf (dump_file
, "Keeping old value ");
3633 print_generic_expr (dump_file
, (*slot
)->result
);
3634 fprintf (dump_file
, " because of collision\n");
3636 free_reference (vr1
);
3637 obstack_free (&vn_tables_obstack
, vr1
);
3642 vr1
->next
= last_inserted_ref
;
3643 last_inserted_ref
= vr1
;
3646 /* Insert a reference by it's pieces into the current hash table with
3647 a value number of RESULT. Return the resulting reference
3648 structure we created. */
3651 vn_reference_insert_pieces (tree vuse
, alias_set_type set
,
3652 alias_set_type base_set
, tree type
,
3653 vec
<vn_reference_op_s
> operands
,
3654 tree result
, unsigned int value_id
)
3657 vn_reference_s
**slot
;
3660 vr1
= XOBNEW (&vn_tables_obstack
, vn_reference_s
);
3661 vr1
->value_id
= value_id
;
3662 vr1
->vuse
= vuse_ssa_val (vuse
);
3663 vr1
->operands
= valueize_refs (operands
);
3665 vr1
->punned
= false;
3667 vr1
->base_set
= base_set
;
3668 vr1
->hashcode
= vn_reference_compute_hash (vr1
);
3669 if (result
&& TREE_CODE (result
) == SSA_NAME
)
3670 result
= SSA_VAL (result
);
3671 vr1
->result
= result
;
3673 slot
= valid_info
->references
->find_slot_with_hash (vr1
, vr1
->hashcode
,
3676 /* At this point we should have all the things inserted that we have
3677 seen before, and we should never try inserting something that
3679 gcc_assert (!*slot
);
3682 vr1
->next
= last_inserted_ref
;
3683 last_inserted_ref
= vr1
;
3687 /* Compute and return the hash value for nary operation VBO1. */
3690 vn_nary_op_compute_hash (const vn_nary_op_t vno1
)
3692 inchash::hash hstate
;
3695 for (i
= 0; i
< vno1
->length
; ++i
)
3696 if (TREE_CODE (vno1
->op
[i
]) == SSA_NAME
)
3697 vno1
->op
[i
] = SSA_VAL (vno1
->op
[i
]);
3699 if (((vno1
->length
== 2
3700 && commutative_tree_code (vno1
->opcode
))
3701 || (vno1
->length
== 3
3702 && commutative_ternary_tree_code (vno1
->opcode
)))
3703 && tree_swap_operands_p (vno1
->op
[0], vno1
->op
[1]))
3704 std::swap (vno1
->op
[0], vno1
->op
[1]);
3705 else if (TREE_CODE_CLASS (vno1
->opcode
) == tcc_comparison
3706 && tree_swap_operands_p (vno1
->op
[0], vno1
->op
[1]))
3708 std::swap (vno1
->op
[0], vno1
->op
[1]);
3709 vno1
->opcode
= swap_tree_comparison (vno1
->opcode
);
3712 hstate
.add_int (vno1
->opcode
);
3713 for (i
= 0; i
< vno1
->length
; ++i
)
3714 inchash::add_expr (vno1
->op
[i
], hstate
);
3716 return hstate
.end ();
3719 /* Compare nary operations VNO1 and VNO2 and return true if they are
3723 vn_nary_op_eq (const_vn_nary_op_t
const vno1
, const_vn_nary_op_t
const vno2
)
3727 if (vno1
->hashcode
!= vno2
->hashcode
)
3730 if (vno1
->length
!= vno2
->length
)
3733 if (vno1
->opcode
!= vno2
->opcode
3734 || !types_compatible_p (vno1
->type
, vno2
->type
))
3737 for (i
= 0; i
< vno1
->length
; ++i
)
3738 if (!expressions_equal_p (vno1
->op
[i
], vno2
->op
[i
]))
3741 /* BIT_INSERT_EXPR has an implict operand as the type precision
3742 of op1. Need to check to make sure they are the same. */
3743 if (vno1
->opcode
== BIT_INSERT_EXPR
3744 && TREE_CODE (vno1
->op
[1]) == INTEGER_CST
3745 && TYPE_PRECISION (TREE_TYPE (vno1
->op
[1]))
3746 != TYPE_PRECISION (TREE_TYPE (vno2
->op
[1])))
3752 /* Initialize VNO from the pieces provided. */
3755 init_vn_nary_op_from_pieces (vn_nary_op_t vno
, unsigned int length
,
3756 enum tree_code code
, tree type
, tree
*ops
)
3759 vno
->length
= length
;
3761 memcpy (&vno
->op
[0], ops
, sizeof (tree
) * length
);
3764 /* Return the number of operands for a vn_nary ops structure from STMT. */
3767 vn_nary_length_from_stmt (gimple
*stmt
)
3769 switch (gimple_assign_rhs_code (stmt
))
3773 case VIEW_CONVERT_EXPR
:
3780 return CONSTRUCTOR_NELTS (gimple_assign_rhs1 (stmt
));
3783 return gimple_num_ops (stmt
) - 1;
3787 /* Initialize VNO from STMT. */
3790 init_vn_nary_op_from_stmt (vn_nary_op_t vno
, gimple
*stmt
)
3794 vno
->opcode
= gimple_assign_rhs_code (stmt
);
3795 vno
->type
= gimple_expr_type (stmt
);
3796 switch (vno
->opcode
)
3800 case VIEW_CONVERT_EXPR
:
3802 vno
->op
[0] = TREE_OPERAND (gimple_assign_rhs1 (stmt
), 0);
3807 vno
->op
[0] = TREE_OPERAND (gimple_assign_rhs1 (stmt
), 0);
3808 vno
->op
[1] = TREE_OPERAND (gimple_assign_rhs1 (stmt
), 1);
3809 vno
->op
[2] = TREE_OPERAND (gimple_assign_rhs1 (stmt
), 2);
3813 vno
->length
= CONSTRUCTOR_NELTS (gimple_assign_rhs1 (stmt
));
3814 for (i
= 0; i
< vno
->length
; ++i
)
3815 vno
->op
[i
] = CONSTRUCTOR_ELT (gimple_assign_rhs1 (stmt
), i
)->value
;
3819 gcc_checking_assert (!gimple_assign_single_p (stmt
));
3820 vno
->length
= gimple_num_ops (stmt
) - 1;
3821 for (i
= 0; i
< vno
->length
; ++i
)
3822 vno
->op
[i
] = gimple_op (stmt
, i
+ 1);
3826 /* Compute the hashcode for VNO and look for it in the hash table;
3827 return the resulting value number if it exists in the hash table.
3828 Return NULL_TREE if it does not exist in the hash table or if the
3829 result field of the operation is NULL. VNRESULT will contain the
3830 vn_nary_op_t from the hashtable if it exists. */
3833 vn_nary_op_lookup_1 (vn_nary_op_t vno
, vn_nary_op_t
*vnresult
)
3835 vn_nary_op_s
**slot
;
3840 vno
->hashcode
= vn_nary_op_compute_hash (vno
);
3841 slot
= valid_info
->nary
->find_slot_with_hash (vno
, vno
->hashcode
, NO_INSERT
);
3846 return (*slot
)->predicated_values
? NULL_TREE
: (*slot
)->u
.result
;
3849 /* Lookup a n-ary operation by its pieces and return the resulting value
3850 number if it exists in the hash table. Return NULL_TREE if it does
3851 not exist in the hash table or if the result field of the operation
3852 is NULL. VNRESULT will contain the vn_nary_op_t from the hashtable
3856 vn_nary_op_lookup_pieces (unsigned int length
, enum tree_code code
,
3857 tree type
, tree
*ops
, vn_nary_op_t
*vnresult
)
3859 vn_nary_op_t vno1
= XALLOCAVAR (struct vn_nary_op_s
,
3860 sizeof_vn_nary_op (length
));
3861 init_vn_nary_op_from_pieces (vno1
, length
, code
, type
, ops
);
3862 return vn_nary_op_lookup_1 (vno1
, vnresult
);
3865 /* Lookup the rhs of STMT in the current hash table, and return the resulting
3866 value number if it exists in the hash table. Return NULL_TREE if
3867 it does not exist in the hash table. VNRESULT will contain the
3868 vn_nary_op_t from the hashtable if it exists. */
3871 vn_nary_op_lookup_stmt (gimple
*stmt
, vn_nary_op_t
*vnresult
)
3874 = XALLOCAVAR (struct vn_nary_op_s
,
3875 sizeof_vn_nary_op (vn_nary_length_from_stmt (stmt
)));
3876 init_vn_nary_op_from_stmt (vno1
, stmt
);
3877 return vn_nary_op_lookup_1 (vno1
, vnresult
);
3880 /* Allocate a vn_nary_op_t with LENGTH operands on STACK. */
3883 alloc_vn_nary_op_noinit (unsigned int length
, struct obstack
*stack
)
3885 return (vn_nary_op_t
) obstack_alloc (stack
, sizeof_vn_nary_op (length
));
3888 /* Allocate and initialize a vn_nary_op_t on CURRENT_INFO's
3892 alloc_vn_nary_op (unsigned int length
, tree result
, unsigned int value_id
)
3894 vn_nary_op_t vno1
= alloc_vn_nary_op_noinit (length
, &vn_tables_obstack
);
3896 vno1
->value_id
= value_id
;
3897 vno1
->length
= length
;
3898 vno1
->predicated_values
= 0;
3899 vno1
->u
.result
= result
;
3904 /* Insert VNO into TABLE. If COMPUTE_HASH is true, then compute
3905 VNO->HASHCODE first. */
3908 vn_nary_op_insert_into (vn_nary_op_t vno
, vn_nary_op_table_type
*table
,
3911 vn_nary_op_s
**slot
;
3915 vno
->hashcode
= vn_nary_op_compute_hash (vno
);
3916 gcc_assert (! vno
->predicated_values
3917 || (! vno
->u
.values
->next
3918 && vno
->u
.values
->n
== 1));
3921 slot
= table
->find_slot_with_hash (vno
, vno
->hashcode
, INSERT
);
3922 vno
->unwind_to
= *slot
;
3925 /* Prefer non-predicated values.
3926 ??? Only if those are constant, otherwise, with constant predicated
3927 value, turn them into predicated values with entry-block validity
3928 (??? but we always find the first valid result currently). */
3929 if ((*slot
)->predicated_values
3930 && ! vno
->predicated_values
)
3932 /* ??? We cannot remove *slot from the unwind stack list.
3933 For the moment we deal with this by skipping not found
3934 entries but this isn't ideal ... */
3936 /* ??? Maintain a stack of states we can unwind in
3937 vn_nary_op_s? But how far do we unwind? In reality
3938 we need to push change records somewhere... Or not
3939 unwind vn_nary_op_s and linking them but instead
3940 unwind the results "list", linking that, which also
3941 doesn't move on hashtable resize. */
3942 /* We can also have a ->unwind_to recording *slot there.
3943 That way we can make u.values a fixed size array with
3944 recording the number of entries but of course we then
3945 have always N copies for each unwind_to-state. Or we
3946 make sure to only ever append and each unwinding will
3947 pop off one entry (but how to deal with predicated
3948 replaced with non-predicated here?) */
3949 vno
->next
= last_inserted_nary
;
3950 last_inserted_nary
= vno
;
3953 else if (vno
->predicated_values
3954 && ! (*slot
)->predicated_values
)
3956 else if (vno
->predicated_values
3957 && (*slot
)->predicated_values
)
3959 /* ??? Factor this all into a insert_single_predicated_value
3961 gcc_assert (!vno
->u
.values
->next
&& vno
->u
.values
->n
== 1);
3963 = BASIC_BLOCK_FOR_FN (cfun
, vno
->u
.values
->valid_dominated_by_p
[0]);
3964 vn_pval
*nval
= vno
->u
.values
;
3965 vn_pval
**next
= &vno
->u
.values
;
3967 for (vn_pval
*val
= (*slot
)->u
.values
; val
; val
= val
->next
)
3969 if (expressions_equal_p (val
->result
, vno
->u
.values
->result
))
3972 for (unsigned i
= 0; i
< val
->n
; ++i
)
3975 = BASIC_BLOCK_FOR_FN (cfun
,
3976 val
->valid_dominated_by_p
[i
]);
3977 if (dominated_by_p (CDI_DOMINATORS
, vno_bb
, val_bb
))
3978 /* Value registered with more generic predicate. */
3980 else if (dominated_by_p (CDI_DOMINATORS
, val_bb
, vno_bb
))
3981 /* Shouldn't happen, we insert in RPO order. */
3985 *next
= (vn_pval
*) obstack_alloc (&vn_tables_obstack
,
3987 + val
->n
* sizeof (int));
3988 (*next
)->next
= NULL
;
3989 (*next
)->result
= val
->result
;
3990 (*next
)->n
= val
->n
+ 1;
3991 memcpy ((*next
)->valid_dominated_by_p
,
3992 val
->valid_dominated_by_p
,
3993 val
->n
* sizeof (int));
3994 (*next
)->valid_dominated_by_p
[val
->n
] = vno_bb
->index
;
3995 next
= &(*next
)->next
;
3996 if (dump_file
&& (dump_flags
& TDF_DETAILS
))
3997 fprintf (dump_file
, "Appending predicate to value.\n");
4000 /* Copy other predicated values. */
4001 *next
= (vn_pval
*) obstack_alloc (&vn_tables_obstack
,
4003 + (val
->n
-1) * sizeof (int));
4004 memcpy (*next
, val
, sizeof (vn_pval
) + (val
->n
-1) * sizeof (int));
4005 (*next
)->next
= NULL
;
4006 next
= &(*next
)->next
;
4012 vno
->next
= last_inserted_nary
;
4013 last_inserted_nary
= vno
;
4017 /* While we do not want to insert things twice it's awkward to
4018 avoid it in the case where visit_nary_op pattern-matches stuff
4019 and ends up simplifying the replacement to itself. We then
4020 get two inserts, one from visit_nary_op and one from
4021 vn_nary_build_or_lookup.
4022 So allow inserts with the same value number. */
4023 if ((*slot
)->u
.result
== vno
->u
.result
)
4027 /* ??? There's also optimistic vs. previous commited state merging
4028 that is problematic for the case of unwinding. */
4030 /* ??? We should return NULL if we do not use 'vno' and have the
4031 caller release it. */
4032 gcc_assert (!*slot
);
4035 vno
->next
= last_inserted_nary
;
4036 last_inserted_nary
= vno
;
4040 /* Insert a n-ary operation into the current hash table using it's
4041 pieces. Return the vn_nary_op_t structure we created and put in
4045 vn_nary_op_insert_pieces (unsigned int length
, enum tree_code code
,
4046 tree type
, tree
*ops
,
4047 tree result
, unsigned int value_id
)
4049 vn_nary_op_t vno1
= alloc_vn_nary_op (length
, result
, value_id
);
4050 init_vn_nary_op_from_pieces (vno1
, length
, code
, type
, ops
);
4051 return vn_nary_op_insert_into (vno1
, valid_info
->nary
, true);
4055 vn_nary_op_insert_pieces_predicated (unsigned int length
, enum tree_code code
,
4056 tree type
, tree
*ops
,
4057 tree result
, unsigned int value_id
,
4060 /* ??? Currently tracking BBs. */
4061 if (! single_pred_p (pred_e
->dest
))
4063 /* Never record for backedges. */
4064 if (pred_e
->flags
& EDGE_DFS_BACK
)
4069 /* Ignore backedges. */
4070 FOR_EACH_EDGE (e
, ei
, pred_e
->dest
->preds
)
4071 if (! dominated_by_p (CDI_DOMINATORS
, e
->src
, e
->dest
))
4076 if (dump_file
&& (dump_flags
& TDF_DETAILS
)
4077 /* ??? Fix dumping, but currently we only get comparisons. */
4078 && TREE_CODE_CLASS (code
) == tcc_comparison
)
4080 fprintf (dump_file
, "Recording on edge %d->%d ", pred_e
->src
->index
,
4081 pred_e
->dest
->index
);
4082 print_generic_expr (dump_file
, ops
[0], TDF_SLIM
);
4083 fprintf (dump_file
, " %s ", get_tree_code_name (code
));
4084 print_generic_expr (dump_file
, ops
[1], TDF_SLIM
);
4085 fprintf (dump_file
, " == %s\n",
4086 integer_zerop (result
) ? "false" : "true");
4088 vn_nary_op_t vno1
= alloc_vn_nary_op (length
, NULL_TREE
, value_id
);
4089 init_vn_nary_op_from_pieces (vno1
, length
, code
, type
, ops
);
4090 vno1
->predicated_values
= 1;
4091 vno1
->u
.values
= (vn_pval
*) obstack_alloc (&vn_tables_obstack
,
4093 vno1
->u
.values
->next
= NULL
;
4094 vno1
->u
.values
->result
= result
;
4095 vno1
->u
.values
->n
= 1;
4096 vno1
->u
.values
->valid_dominated_by_p
[0] = pred_e
->dest
->index
;
4097 return vn_nary_op_insert_into (vno1
, valid_info
->nary
, true);
4101 dominated_by_p_w_unex (basic_block bb1
, basic_block bb2
);
4104 vn_nary_op_get_predicated_value (vn_nary_op_t vno
, basic_block bb
)
4106 if (! vno
->predicated_values
)
4107 return vno
->u
.result
;
4108 for (vn_pval
*val
= vno
->u
.values
; val
; val
= val
->next
)
4109 for (unsigned i
= 0; i
< val
->n
; ++i
)
4110 if (dominated_by_p_w_unex (bb
,
4112 (cfun
, val
->valid_dominated_by_p
[i
])))
4117 /* Insert the rhs of STMT into the current hash table with a value number of
4121 vn_nary_op_insert_stmt (gimple
*stmt
, tree result
)
4124 = alloc_vn_nary_op (vn_nary_length_from_stmt (stmt
),
4125 result
, VN_INFO (result
)->value_id
);
4126 init_vn_nary_op_from_stmt (vno1
, stmt
);
4127 return vn_nary_op_insert_into (vno1
, valid_info
->nary
, true);
4130 /* Compute a hashcode for PHI operation VP1 and return it. */
4132 static inline hashval_t
4133 vn_phi_compute_hash (vn_phi_t vp1
)
4135 inchash::hash
hstate (EDGE_COUNT (vp1
->block
->preds
) > 2
4136 ? vp1
->block
->index
: EDGE_COUNT (vp1
->block
->preds
));
4142 /* If all PHI arguments are constants we need to distinguish
4143 the PHI node via its type. */
4145 hstate
.merge_hash (vn_hash_type (type
));
4147 FOR_EACH_EDGE (e
, ei
, vp1
->block
->preds
)
4149 /* Don't hash backedge values they need to be handled as VN_TOP
4150 for optimistic value-numbering. */
4151 if (e
->flags
& EDGE_DFS_BACK
)
4154 phi1op
= vp1
->phiargs
[e
->dest_idx
];
4155 if (phi1op
== VN_TOP
)
4157 inchash::add_expr (phi1op
, hstate
);
4160 return hstate
.end ();
4164 /* Return true if COND1 and COND2 represent the same condition, set
4165 *INVERTED_P if one needs to be inverted to make it the same as
4169 cond_stmts_equal_p (gcond
*cond1
, tree lhs1
, tree rhs1
,
4170 gcond
*cond2
, tree lhs2
, tree rhs2
, bool *inverted_p
)
4172 enum tree_code code1
= gimple_cond_code (cond1
);
4173 enum tree_code code2
= gimple_cond_code (cond2
);
4175 *inverted_p
= false;
4178 else if (code1
== swap_tree_comparison (code2
))
4179 std::swap (lhs2
, rhs2
);
4180 else if (code1
== invert_tree_comparison (code2
, HONOR_NANS (lhs2
)))
4182 else if (code1
== invert_tree_comparison
4183 (swap_tree_comparison (code2
), HONOR_NANS (lhs2
)))
4185 std::swap (lhs2
, rhs2
);
4191 return ((expressions_equal_p (lhs1
, lhs2
)
4192 && expressions_equal_p (rhs1
, rhs2
))
4193 || (commutative_tree_code (code1
)
4194 && expressions_equal_p (lhs1
, rhs2
)
4195 && expressions_equal_p (rhs1
, lhs2
)));
4198 /* Compare two phi entries for equality, ignoring VN_TOP arguments. */
4201 vn_phi_eq (const_vn_phi_t
const vp1
, const_vn_phi_t
const vp2
)
4203 if (vp1
->hashcode
!= vp2
->hashcode
)
4206 if (vp1
->block
!= vp2
->block
)
4208 if (EDGE_COUNT (vp1
->block
->preds
) != EDGE_COUNT (vp2
->block
->preds
))
4211 switch (EDGE_COUNT (vp1
->block
->preds
))
4214 /* Single-arg PHIs are just copies. */
4219 /* Rule out backedges into the PHI. */
4220 if (vp1
->block
->loop_father
->header
== vp1
->block
4221 || vp2
->block
->loop_father
->header
== vp2
->block
)
4224 /* If the PHI nodes do not have compatible types
4225 they are not the same. */
4226 if (!types_compatible_p (vp1
->type
, vp2
->type
))
4230 = get_immediate_dominator (CDI_DOMINATORS
, vp1
->block
);
4232 = get_immediate_dominator (CDI_DOMINATORS
, vp2
->block
);
4233 /* If the immediate dominator end in switch stmts multiple
4234 values may end up in the same PHI arg via intermediate
4236 if (EDGE_COUNT (idom1
->succs
) != 2
4237 || EDGE_COUNT (idom2
->succs
) != 2)
4240 /* Verify the controlling stmt is the same. */
4241 gcond
*last1
= safe_dyn_cast
<gcond
*> (last_stmt (idom1
));
4242 gcond
*last2
= safe_dyn_cast
<gcond
*> (last_stmt (idom2
));
4243 if (! last1
|| ! last2
)
4246 if (! cond_stmts_equal_p (last1
, vp1
->cclhs
, vp1
->ccrhs
,
4247 last2
, vp2
->cclhs
, vp2
->ccrhs
,
4251 /* Get at true/false controlled edges into the PHI. */
4252 edge te1
, te2
, fe1
, fe2
;
4253 if (! extract_true_false_controlled_edges (idom1
, vp1
->block
,
4255 || ! extract_true_false_controlled_edges (idom2
, vp2
->block
,
4259 /* Swap edges if the second condition is the inverted of the
4262 std::swap (te2
, fe2
);
4264 /* ??? Handle VN_TOP specially. */
4265 if (! expressions_equal_p (vp1
->phiargs
[te1
->dest_idx
],
4266 vp2
->phiargs
[te2
->dest_idx
])
4267 || ! expressions_equal_p (vp1
->phiargs
[fe1
->dest_idx
],
4268 vp2
->phiargs
[fe2
->dest_idx
]))
4279 /* If the PHI nodes do not have compatible types
4280 they are not the same. */
4281 if (!types_compatible_p (vp1
->type
, vp2
->type
))
4284 /* Any phi in the same block will have it's arguments in the
4285 same edge order, because of how we store phi nodes. */
4286 for (unsigned i
= 0; i
< EDGE_COUNT (vp1
->block
->preds
); ++i
)
4288 tree phi1op
= vp1
->phiargs
[i
];
4289 tree phi2op
= vp2
->phiargs
[i
];
4290 if (phi1op
== VN_TOP
|| phi2op
== VN_TOP
)
4292 if (!expressions_equal_p (phi1op
, phi2op
))
4299 /* Lookup PHI in the current hash table, and return the resulting
4300 value number if it exists in the hash table. Return NULL_TREE if
4301 it does not exist in the hash table. */
4304 vn_phi_lookup (gimple
*phi
, bool backedges_varying_p
)
4307 struct vn_phi_s
*vp1
;
4311 vp1
= XALLOCAVAR (struct vn_phi_s
,
4312 sizeof (struct vn_phi_s
)
4313 + (gimple_phi_num_args (phi
) - 1) * sizeof (tree
));
4315 /* Canonicalize the SSA_NAME's to their value number. */
4316 FOR_EACH_EDGE (e
, ei
, gimple_bb (phi
)->preds
)
4318 tree def
= PHI_ARG_DEF_FROM_EDGE (phi
, e
);
4319 if (TREE_CODE (def
) == SSA_NAME
4320 && (!backedges_varying_p
|| !(e
->flags
& EDGE_DFS_BACK
)))
4321 def
= SSA_VAL (def
);
4322 vp1
->phiargs
[e
->dest_idx
] = def
;
4324 vp1
->type
= TREE_TYPE (gimple_phi_result (phi
));
4325 vp1
->block
= gimple_bb (phi
);
4326 /* Extract values of the controlling condition. */
4327 vp1
->cclhs
= NULL_TREE
;
4328 vp1
->ccrhs
= NULL_TREE
;
4329 basic_block idom1
= get_immediate_dominator (CDI_DOMINATORS
, vp1
->block
);
4330 if (EDGE_COUNT (idom1
->succs
) == 2)
4331 if (gcond
*last1
= safe_dyn_cast
<gcond
*> (last_stmt (idom1
)))
4333 /* ??? We want to use SSA_VAL here. But possibly not
4335 vp1
->cclhs
= vn_valueize (gimple_cond_lhs (last1
));
4336 vp1
->ccrhs
= vn_valueize (gimple_cond_rhs (last1
));
4338 vp1
->hashcode
= vn_phi_compute_hash (vp1
);
4339 slot
= valid_info
->phis
->find_slot_with_hash (vp1
, vp1
->hashcode
, NO_INSERT
);
4342 return (*slot
)->result
;
4345 /* Insert PHI into the current hash table with a value number of
4349 vn_phi_insert (gimple
*phi
, tree result
, bool backedges_varying_p
)
4352 vn_phi_t vp1
= (vn_phi_t
) obstack_alloc (&vn_tables_obstack
,
4354 + ((gimple_phi_num_args (phi
) - 1)
4359 /* Canonicalize the SSA_NAME's to their value number. */
4360 FOR_EACH_EDGE (e
, ei
, gimple_bb (phi
)->preds
)
4362 tree def
= PHI_ARG_DEF_FROM_EDGE (phi
, e
);
4363 if (TREE_CODE (def
) == SSA_NAME
4364 && (!backedges_varying_p
|| !(e
->flags
& EDGE_DFS_BACK
)))
4365 def
= SSA_VAL (def
);
4366 vp1
->phiargs
[e
->dest_idx
] = def
;
4368 vp1
->value_id
= VN_INFO (result
)->value_id
;
4369 vp1
->type
= TREE_TYPE (gimple_phi_result (phi
));
4370 vp1
->block
= gimple_bb (phi
);
4371 /* Extract values of the controlling condition. */
4372 vp1
->cclhs
= NULL_TREE
;
4373 vp1
->ccrhs
= NULL_TREE
;
4374 basic_block idom1
= get_immediate_dominator (CDI_DOMINATORS
, vp1
->block
);
4375 if (EDGE_COUNT (idom1
->succs
) == 2)
4376 if (gcond
*last1
= safe_dyn_cast
<gcond
*> (last_stmt (idom1
)))
4378 /* ??? We want to use SSA_VAL here. But possibly not
4380 vp1
->cclhs
= vn_valueize (gimple_cond_lhs (last1
));
4381 vp1
->ccrhs
= vn_valueize (gimple_cond_rhs (last1
));
4383 vp1
->result
= result
;
4384 vp1
->hashcode
= vn_phi_compute_hash (vp1
);
4386 slot
= valid_info
->phis
->find_slot_with_hash (vp1
, vp1
->hashcode
, INSERT
);
4387 gcc_assert (!*slot
);
4390 vp1
->next
= last_inserted_phi
;
4391 last_inserted_phi
= vp1
;
4396 /* Return true if BB1 is dominated by BB2 taking into account edges
4397 that are not executable. */
4400 dominated_by_p_w_unex (basic_block bb1
, basic_block bb2
)
4405 if (dominated_by_p (CDI_DOMINATORS
, bb1
, bb2
))
4408 /* Before iterating we'd like to know if there exists a
4409 (executable) path from bb2 to bb1 at all, if not we can
4410 directly return false. For now simply iterate once. */
4412 /* Iterate to the single executable bb1 predecessor. */
4413 if (EDGE_COUNT (bb1
->preds
) > 1)
4416 FOR_EACH_EDGE (e
, ei
, bb1
->preds
)
4417 if (e
->flags
& EDGE_EXECUTABLE
)
4430 /* Re-do the dominance check with changed bb1. */
4431 if (dominated_by_p (CDI_DOMINATORS
, bb1
, bb2
))
4436 /* Iterate to the single executable bb2 successor. */
4438 FOR_EACH_EDGE (e
, ei
, bb2
->succs
)
4439 if (e
->flags
& EDGE_EXECUTABLE
)
4450 /* Verify the reached block is only reached through succe.
4451 If there is only one edge we can spare us the dominator
4452 check and iterate directly. */
4453 if (EDGE_COUNT (succe
->dest
->preds
) > 1)
4455 FOR_EACH_EDGE (e
, ei
, succe
->dest
->preds
)
4457 && (e
->flags
& EDGE_EXECUTABLE
))
4467 /* Re-do the dominance check with changed bb2. */
4468 if (dominated_by_p (CDI_DOMINATORS
, bb1
, bb2
))
4473 /* We could now iterate updating bb1 / bb2. */
4477 /* Set the value number of FROM to TO, return true if it has changed
4481 set_ssa_val_to (tree from
, tree to
)
4483 vn_ssa_aux_t from_info
= VN_INFO (from
);
4484 tree currval
= from_info
->valnum
; // SSA_VAL (from)
4485 poly_int64 toff
, coff
;
4486 bool curr_undefined
= false;
4487 bool curr_invariant
= false;
4489 /* The only thing we allow as value numbers are ssa_names
4490 and invariants. So assert that here. We don't allow VN_TOP
4491 as visiting a stmt should produce a value-number other than
4493 ??? Still VN_TOP can happen for unreachable code, so force
4494 it to varying in that case. Not all code is prepared to
4495 get VN_TOP on valueization. */
4498 /* ??? When iterating and visiting PHI <undef, backedge-value>
4499 for the first time we rightfully get VN_TOP and we need to
4500 preserve that to optimize for example gcc.dg/tree-ssa/ssa-sccvn-2.c.
4501 With SCCVN we were simply lucky we iterated the other PHI
4502 cycles first and thus visited the backedge-value DEF. */
4503 if (currval
== VN_TOP
)
4505 if (dump_file
&& (dump_flags
& TDF_DETAILS
))
4506 fprintf (dump_file
, "Forcing value number to varying on "
4507 "receiving VN_TOP\n");
4511 gcc_checking_assert (to
!= NULL_TREE
4512 && ((TREE_CODE (to
) == SSA_NAME
4513 && (to
== from
|| SSA_VAL (to
) == to
))
4514 || is_gimple_min_invariant (to
)));
4518 if (currval
== from
)
4520 if (dump_file
&& (dump_flags
& TDF_DETAILS
))
4522 fprintf (dump_file
, "Not changing value number of ");
4523 print_generic_expr (dump_file
, from
);
4524 fprintf (dump_file
, " from VARYING to ");
4525 print_generic_expr (dump_file
, to
);
4526 fprintf (dump_file
, "\n");
4530 curr_invariant
= is_gimple_min_invariant (currval
);
4531 curr_undefined
= (TREE_CODE (currval
) == SSA_NAME
4532 && ssa_undefined_value_p (currval
, false));
4533 if (currval
!= VN_TOP
4536 && is_gimple_min_invariant (to
))
4538 if (dump_file
&& (dump_flags
& TDF_DETAILS
))
4540 fprintf (dump_file
, "Forcing VARYING instead of changing "
4541 "value number of ");
4542 print_generic_expr (dump_file
, from
);
4543 fprintf (dump_file
, " from ");
4544 print_generic_expr (dump_file
, currval
);
4545 fprintf (dump_file
, " (non-constant) to ");
4546 print_generic_expr (dump_file
, to
);
4547 fprintf (dump_file
, " (constant)\n");
4551 else if (currval
!= VN_TOP
4553 && TREE_CODE (to
) == SSA_NAME
4554 && ssa_undefined_value_p (to
, false))
4556 if (dump_file
&& (dump_flags
& TDF_DETAILS
))
4558 fprintf (dump_file
, "Forcing VARYING instead of changing "
4559 "value number of ");
4560 print_generic_expr (dump_file
, from
);
4561 fprintf (dump_file
, " from ");
4562 print_generic_expr (dump_file
, currval
);
4563 fprintf (dump_file
, " (non-undefined) to ");
4564 print_generic_expr (dump_file
, to
);
4565 fprintf (dump_file
, " (undefined)\n");
4569 else if (TREE_CODE (to
) == SSA_NAME
4570 && SSA_NAME_OCCURS_IN_ABNORMAL_PHI (to
))
4575 if (dump_file
&& (dump_flags
& TDF_DETAILS
))
4577 fprintf (dump_file
, "Setting value number of ");
4578 print_generic_expr (dump_file
, from
);
4579 fprintf (dump_file
, " to ");
4580 print_generic_expr (dump_file
, to
);
4584 && !operand_equal_p (currval
, to
, 0)
4585 /* Different undefined SSA names are not actually different. See
4586 PR82320 for a testcase were we'd otherwise not terminate iteration. */
4588 && TREE_CODE (to
) == SSA_NAME
4589 && ssa_undefined_value_p (to
, false))
4590 /* ??? For addresses involving volatile objects or types operand_equal_p
4591 does not reliably detect ADDR_EXPRs as equal. We know we are only
4592 getting invariant gimple addresses here, so can use
4593 get_addr_base_and_unit_offset to do this comparison. */
4594 && !(TREE_CODE (currval
) == ADDR_EXPR
4595 && TREE_CODE (to
) == ADDR_EXPR
4596 && (get_addr_base_and_unit_offset (TREE_OPERAND (currval
, 0), &coff
)
4597 == get_addr_base_and_unit_offset (TREE_OPERAND (to
, 0), &toff
))
4598 && known_eq (coff
, toff
)))
4601 && currval
!= VN_TOP
4603 /* We do not want to allow lattice transitions from one value
4604 to another since that may lead to not terminating iteration
4605 (see PR95049). Since there's no convenient way to check
4606 for the allowed transition of VAL -> PHI (loop entry value,
4607 same on two PHIs, to same PHI result) we restrict the check
4610 && is_gimple_min_invariant (to
))
4612 if (dump_file
&& (dump_flags
& TDF_DETAILS
))
4613 fprintf (dump_file
, " forced VARYING");
4616 if (dump_file
&& (dump_flags
& TDF_DETAILS
))
4617 fprintf (dump_file
, " (changed)\n");
4618 from_info
->valnum
= to
;
4621 if (dump_file
&& (dump_flags
& TDF_DETAILS
))
4622 fprintf (dump_file
, "\n");
4626 /* Set all definitions in STMT to value number to themselves.
4627 Return true if a value number changed. */
4630 defs_to_varying (gimple
*stmt
)
4632 bool changed
= false;
4636 FOR_EACH_SSA_DEF_OPERAND (defp
, stmt
, iter
, SSA_OP_ALL_DEFS
)
4638 tree def
= DEF_FROM_PTR (defp
);
4639 changed
|= set_ssa_val_to (def
, def
);
4644 /* Visit a copy between LHS and RHS, return true if the value number
4648 visit_copy (tree lhs
, tree rhs
)
4651 rhs
= SSA_VAL (rhs
);
4653 return set_ssa_val_to (lhs
, rhs
);
4656 /* Lookup a value for OP in type WIDE_TYPE where the value in type of OP
4660 valueized_wider_op (tree wide_type
, tree op
)
4662 if (TREE_CODE (op
) == SSA_NAME
)
4663 op
= vn_valueize (op
);
4665 /* Either we have the op widened available. */
4668 tree tem
= vn_nary_op_lookup_pieces (1, NOP_EXPR
,
4669 wide_type
, ops
, NULL
);
4673 /* Or the op is truncated from some existing value. */
4674 if (TREE_CODE (op
) == SSA_NAME
)
4676 gimple
*def
= SSA_NAME_DEF_STMT (op
);
4677 if (is_gimple_assign (def
)
4678 && CONVERT_EXPR_CODE_P (gimple_assign_rhs_code (def
)))
4680 tem
= gimple_assign_rhs1 (def
);
4681 if (useless_type_conversion_p (wide_type
, TREE_TYPE (tem
)))
4683 if (TREE_CODE (tem
) == SSA_NAME
)
4684 tem
= vn_valueize (tem
);
4690 /* For constants simply extend it. */
4691 if (TREE_CODE (op
) == INTEGER_CST
)
4692 return wide_int_to_tree (wide_type
, wi::to_wide (op
));
4697 /* Visit a nary operator RHS, value number it, and return true if the
4698 value number of LHS has changed as a result. */
4701 visit_nary_op (tree lhs
, gassign
*stmt
)
4703 vn_nary_op_t vnresult
;
4704 tree result
= vn_nary_op_lookup_stmt (stmt
, &vnresult
);
4705 if (! result
&& vnresult
)
4706 result
= vn_nary_op_get_predicated_value (vnresult
, gimple_bb (stmt
));
4708 return set_ssa_val_to (lhs
, result
);
4710 /* Do some special pattern matching for redundancies of operations
4711 in different types. */
4712 enum tree_code code
= gimple_assign_rhs_code (stmt
);
4713 tree type
= TREE_TYPE (lhs
);
4714 tree rhs1
= gimple_assign_rhs1 (stmt
);
4718 /* Match arithmetic done in a different type where we can easily
4719 substitute the result from some earlier sign-changed or widened
4721 if (INTEGRAL_TYPE_P (type
)
4722 && TREE_CODE (rhs1
) == SSA_NAME
4723 /* We only handle sign-changes, zero-extension -> & mask or
4724 sign-extension if we know the inner operation doesn't
4726 && (((TYPE_UNSIGNED (TREE_TYPE (rhs1
))
4727 || (INTEGRAL_TYPE_P (TREE_TYPE (rhs1
))
4728 && TYPE_OVERFLOW_UNDEFINED (TREE_TYPE (rhs1
))))
4729 && TYPE_PRECISION (type
) > TYPE_PRECISION (TREE_TYPE (rhs1
)))
4730 || TYPE_PRECISION (type
) == TYPE_PRECISION (TREE_TYPE (rhs1
))))
4732 gassign
*def
= dyn_cast
<gassign
*> (SSA_NAME_DEF_STMT (rhs1
));
4734 && (gimple_assign_rhs_code (def
) == PLUS_EXPR
4735 || gimple_assign_rhs_code (def
) == MINUS_EXPR
4736 || gimple_assign_rhs_code (def
) == MULT_EXPR
))
4739 /* Either we have the op widened available. */
4740 ops
[0] = valueized_wider_op (type
,
4741 gimple_assign_rhs1 (def
));
4743 ops
[1] = valueized_wider_op (type
,
4744 gimple_assign_rhs2 (def
));
4745 if (ops
[0] && ops
[1])
4747 ops
[0] = vn_nary_op_lookup_pieces
4748 (2, gimple_assign_rhs_code (def
), type
, ops
, NULL
);
4749 /* We have wider operation available. */
4751 /* If the leader is a wrapping operation we can
4752 insert it for code hoisting w/o introducing
4753 undefined overflow. If it is not it has to
4754 be available. See PR86554. */
4755 && (TYPE_OVERFLOW_WRAPS (TREE_TYPE (ops
[0]))
4756 || (rpo_avail
&& vn_context_bb
4757 && rpo_avail
->eliminate_avail (vn_context_bb
,
4760 unsigned lhs_prec
= TYPE_PRECISION (type
);
4761 unsigned rhs_prec
= TYPE_PRECISION (TREE_TYPE (rhs1
));
4762 if (lhs_prec
== rhs_prec
4763 || (INTEGRAL_TYPE_P (TREE_TYPE (rhs1
))
4764 && TYPE_OVERFLOW_UNDEFINED (TREE_TYPE (rhs1
))))
4766 gimple_match_op
match_op (gimple_match_cond::UNCOND
,
4767 NOP_EXPR
, type
, ops
[0]);
4768 result
= vn_nary_build_or_lookup (&match_op
);
4771 bool changed
= set_ssa_val_to (lhs
, result
);
4772 vn_nary_op_insert_stmt (stmt
, result
);
4778 tree mask
= wide_int_to_tree
4779 (type
, wi::mask (rhs_prec
, false, lhs_prec
));
4780 gimple_match_op
match_op (gimple_match_cond::UNCOND
,
4784 result
= vn_nary_build_or_lookup (&match_op
);
4787 bool changed
= set_ssa_val_to (lhs
, result
);
4788 vn_nary_op_insert_stmt (stmt
, result
);
4798 if (INTEGRAL_TYPE_P (type
)
4799 && TREE_CODE (rhs1
) == SSA_NAME
4800 && TREE_CODE (gimple_assign_rhs2 (stmt
)) == INTEGER_CST
4801 && !SSA_NAME_OCCURS_IN_ABNORMAL_PHI (rhs1
)
4802 && default_vn_walk_kind
!= VN_NOWALK
4804 && BITS_PER_UNIT
== 8
4805 && BYTES_BIG_ENDIAN
== WORDS_BIG_ENDIAN
4806 && !integer_all_onesp (gimple_assign_rhs2 (stmt
))
4807 && !integer_zerop (gimple_assign_rhs2 (stmt
)))
4809 gassign
*ass
= dyn_cast
<gassign
*> (SSA_NAME_DEF_STMT (rhs1
));
4811 && !gimple_has_volatile_ops (ass
)
4812 && vn_get_stmt_kind (ass
) == VN_REFERENCE
)
4814 tree last_vuse
= gimple_vuse (ass
);
4815 tree op
= gimple_assign_rhs1 (ass
);
4816 tree result
= vn_reference_lookup (op
, gimple_vuse (ass
),
4817 default_vn_walk_kind
,
4818 NULL
, true, &last_vuse
,
4819 gimple_assign_rhs2 (stmt
));
4821 && useless_type_conversion_p (TREE_TYPE (result
),
4823 return set_ssa_val_to (lhs
, result
);
4831 bool changed
= set_ssa_val_to (lhs
, lhs
);
4832 vn_nary_op_insert_stmt (stmt
, lhs
);
4836 /* Visit a call STMT storing into LHS. Return true if the value number
4837 of the LHS has changed as a result. */
4840 visit_reference_op_call (tree lhs
, gcall
*stmt
)
4842 bool changed
= false;
4843 struct vn_reference_s vr1
;
4844 vn_reference_t vnresult
= NULL
;
4845 tree vdef
= gimple_vdef (stmt
);
4847 /* Non-ssa lhs is handled in copy_reference_ops_from_call. */
4848 if (lhs
&& TREE_CODE (lhs
) != SSA_NAME
)
4851 vn_reference_lookup_call (stmt
, &vnresult
, &vr1
);
4854 if (vnresult
->result_vdef
&& vdef
)
4855 changed
|= set_ssa_val_to (vdef
, vnresult
->result_vdef
);
4857 /* If the call was discovered to be pure or const reflect
4858 that as far as possible. */
4859 changed
|= set_ssa_val_to (vdef
, vuse_ssa_val (gimple_vuse (stmt
)));
4861 if (!vnresult
->result
&& lhs
)
4862 vnresult
->result
= lhs
;
4864 if (vnresult
->result
&& lhs
)
4865 changed
|= set_ssa_val_to (lhs
, vnresult
->result
);
4870 vn_reference_s
**slot
;
4871 tree vdef_val
= vdef
;
4874 /* If we value numbered an indirect functions function to
4875 one not clobbering memory value number its VDEF to its
4877 tree fn
= gimple_call_fn (stmt
);
4878 if (fn
&& TREE_CODE (fn
) == SSA_NAME
)
4881 if (TREE_CODE (fn
) == ADDR_EXPR
4882 && TREE_CODE (TREE_OPERAND (fn
, 0)) == FUNCTION_DECL
4883 && (flags_from_decl_or_type (TREE_OPERAND (fn
, 0))
4884 & (ECF_CONST
| ECF_PURE
)))
4885 vdef_val
= vuse_ssa_val (gimple_vuse (stmt
));
4887 changed
|= set_ssa_val_to (vdef
, vdef_val
);
4890 changed
|= set_ssa_val_to (lhs
, lhs
);
4891 vr2
= XOBNEW (&vn_tables_obstack
, vn_reference_s
);
4892 vr2
->vuse
= vr1
.vuse
;
4893 /* As we are not walking the virtual operand chain we know the
4894 shared_lookup_references are still original so we can re-use
4896 vr2
->operands
= vr1
.operands
.copy ();
4897 vr2
->type
= vr1
.type
;
4898 vr2
->punned
= vr1
.punned
;
4900 vr2
->base_set
= vr1
.base_set
;
4901 vr2
->hashcode
= vr1
.hashcode
;
4903 vr2
->result_vdef
= vdef_val
;
4905 slot
= valid_info
->references
->find_slot_with_hash (vr2
, vr2
->hashcode
,
4907 gcc_assert (!*slot
);
4909 vr2
->next
= last_inserted_ref
;
4910 last_inserted_ref
= vr2
;
4916 /* Visit a load from a reference operator RHS, part of STMT, value number it,
4917 and return true if the value number of the LHS has changed as a result. */
4920 visit_reference_op_load (tree lhs
, tree op
, gimple
*stmt
)
4922 bool changed
= false;
4927 last_vuse
= gimple_vuse (stmt
);
4928 result
= vn_reference_lookup (op
, gimple_vuse (stmt
),
4929 default_vn_walk_kind
, &res
, true, &last_vuse
);
4931 /* We handle type-punning through unions by value-numbering based
4932 on offset and size of the access. Be prepared to handle a
4933 type-mismatch here via creating a VIEW_CONVERT_EXPR. */
4935 && !useless_type_conversion_p (TREE_TYPE (result
), TREE_TYPE (op
)))
4937 /* Avoid the type punning in case the result mode has padding where
4938 the op we lookup has not. */
4939 if (maybe_lt (GET_MODE_PRECISION (TYPE_MODE (TREE_TYPE (result
))),
4940 GET_MODE_PRECISION (TYPE_MODE (TREE_TYPE (op
)))))
4944 /* We will be setting the value number of lhs to the value number
4945 of VIEW_CONVERT_EXPR <TREE_TYPE (result)> (result).
4946 So first simplify and lookup this expression to see if it
4947 is already available. */
4948 gimple_match_op
res_op (gimple_match_cond::UNCOND
,
4949 VIEW_CONVERT_EXPR
, TREE_TYPE (op
), result
);
4950 result
= vn_nary_build_or_lookup (&res_op
);
4952 && TREE_CODE (result
) == SSA_NAME
4953 && VN_INFO (result
)->needs_insertion
)
4954 /* Track whether this is the canonical expression for different
4955 typed loads. We use that as a stopgap measure for code
4956 hoisting when dealing with floating point loads. */
4960 /* When building the conversion fails avoid inserting the reference
4963 return set_ssa_val_to (lhs
, lhs
);
4967 changed
= set_ssa_val_to (lhs
, result
);
4970 changed
= set_ssa_val_to (lhs
, lhs
);
4971 vn_reference_insert (op
, lhs
, last_vuse
, NULL_TREE
);
4978 /* Visit a store to a reference operator LHS, part of STMT, value number it,
4979 and return true if the value number of the LHS has changed as a result. */
4982 visit_reference_op_store (tree lhs
, tree op
, gimple
*stmt
)
4984 bool changed
= false;
4985 vn_reference_t vnresult
= NULL
;
4987 bool resultsame
= false;
4988 tree vuse
= gimple_vuse (stmt
);
4989 tree vdef
= gimple_vdef (stmt
);
4991 if (TREE_CODE (op
) == SSA_NAME
)
4994 /* First we want to lookup using the *vuses* from the store and see
4995 if there the last store to this location with the same address
4998 The vuses represent the memory state before the store. If the
4999 memory state, address, and value of the store is the same as the
5000 last store to this location, then this store will produce the
5001 same memory state as that store.
5003 In this case the vdef versions for this store are value numbered to those
5004 vuse versions, since they represent the same memory state after
5007 Otherwise, the vdefs for the store are used when inserting into
5008 the table, since the store generates a new memory state. */
5010 vn_reference_lookup (lhs
, vuse
, VN_NOWALK
, &vnresult
, false);
5012 && vnresult
->result
)
5014 tree result
= vnresult
->result
;
5015 gcc_checking_assert (TREE_CODE (result
) != SSA_NAME
5016 || result
== SSA_VAL (result
));
5017 resultsame
= expressions_equal_p (result
, op
);
5020 /* If the TBAA state isn't compatible for downstream reads
5021 we cannot value-number the VDEFs the same. */
5023 ao_ref_init (&lhs_ref
, lhs
);
5024 alias_set_type set
= ao_ref_alias_set (&lhs_ref
);
5025 alias_set_type base_set
= ao_ref_base_alias_set (&lhs_ref
);
5026 if ((vnresult
->set
!= set
5027 && ! alias_set_subset_of (set
, vnresult
->set
))
5028 || (vnresult
->base_set
!= base_set
5029 && ! alias_set_subset_of (base_set
, vnresult
->base_set
)))
5036 /* Only perform the following when being called from PRE
5037 which embeds tail merging. */
5038 if (default_vn_walk_kind
== VN_WALK
)
5040 assign
= build2 (MODIFY_EXPR
, TREE_TYPE (lhs
), lhs
, op
);
5041 vn_reference_lookup (assign
, vuse
, VN_NOWALK
, &vnresult
, false);
5044 VN_INFO (vdef
)->visited
= true;
5045 return set_ssa_val_to (vdef
, vnresult
->result_vdef
);
5049 if (dump_file
&& (dump_flags
& TDF_DETAILS
))
5051 fprintf (dump_file
, "No store match\n");
5052 fprintf (dump_file
, "Value numbering store ");
5053 print_generic_expr (dump_file
, lhs
);
5054 fprintf (dump_file
, " to ");
5055 print_generic_expr (dump_file
, op
);
5056 fprintf (dump_file
, "\n");
5058 /* Have to set value numbers before insert, since insert is
5059 going to valueize the references in-place. */
5061 changed
|= set_ssa_val_to (vdef
, vdef
);
5063 /* Do not insert structure copies into the tables. */
5064 if (is_gimple_min_invariant (op
)
5065 || is_gimple_reg (op
))
5066 vn_reference_insert (lhs
, op
, vdef
, NULL
);
5068 /* Only perform the following when being called from PRE
5069 which embeds tail merging. */
5070 if (default_vn_walk_kind
== VN_WALK
)
5072 assign
= build2 (MODIFY_EXPR
, TREE_TYPE (lhs
), lhs
, op
);
5073 vn_reference_insert (assign
, lhs
, vuse
, vdef
);
5078 /* We had a match, so value number the vdef to have the value
5079 number of the vuse it came from. */
5081 if (dump_file
&& (dump_flags
& TDF_DETAILS
))
5082 fprintf (dump_file
, "Store matched earlier value, "
5083 "value numbering store vdefs to matching vuses.\n");
5085 changed
|= set_ssa_val_to (vdef
, SSA_VAL (vuse
));
5091 /* Visit and value number PHI, return true if the value number
5092 changed. When BACKEDGES_VARYING_P is true then assume all
5093 backedge values are varying. When INSERTED is not NULL then
5094 this is just a ahead query for a possible iteration, set INSERTED
5095 to true if we'd insert into the hashtable. */
5098 visit_phi (gimple
*phi
, bool *inserted
, bool backedges_varying_p
)
5100 tree result
, sameval
= VN_TOP
, seen_undef
= NULL_TREE
;
5101 tree backedge_val
= NULL_TREE
;
5102 bool seen_non_backedge
= false;
5103 tree sameval_base
= NULL_TREE
;
5104 poly_int64 soff
, doff
;
5105 unsigned n_executable
= 0;
5109 /* TODO: We could check for this in initialization, and replace this
5110 with a gcc_assert. */
5111 if (SSA_NAME_OCCURS_IN_ABNORMAL_PHI (PHI_RESULT (phi
)))
5112 return set_ssa_val_to (PHI_RESULT (phi
), PHI_RESULT (phi
));
5114 /* We track whether a PHI was CSEd to to avoid excessive iterations
5115 that would be necessary only because the PHI changed arguments
5118 gimple_set_plf (phi
, GF_PLF_1
, false);
5120 /* See if all non-TOP arguments have the same value. TOP is
5121 equivalent to everything, so we can ignore it. */
5122 FOR_EACH_EDGE (e
, ei
, gimple_bb (phi
)->preds
)
5123 if (e
->flags
& EDGE_EXECUTABLE
)
5125 tree def
= PHI_ARG_DEF_FROM_EDGE (phi
, e
);
5128 if (TREE_CODE (def
) == SSA_NAME
)
5130 if (!backedges_varying_p
|| !(e
->flags
& EDGE_DFS_BACK
))
5131 def
= SSA_VAL (def
);
5132 if (e
->flags
& EDGE_DFS_BACK
)
5135 if (!(e
->flags
& EDGE_DFS_BACK
))
5136 seen_non_backedge
= true;
5139 /* Ignore undefined defs for sameval but record one. */
5140 else if (TREE_CODE (def
) == SSA_NAME
5141 && ! virtual_operand_p (def
)
5142 && ssa_undefined_value_p (def
, false))
5144 else if (sameval
== VN_TOP
)
5146 else if (!expressions_equal_p (def
, sameval
))
5148 /* We know we're arriving only with invariant addresses here,
5149 try harder comparing them. We can do some caching here
5150 which we cannot do in expressions_equal_p. */
5151 if (TREE_CODE (def
) == ADDR_EXPR
5152 && TREE_CODE (sameval
) == ADDR_EXPR
5153 && sameval_base
!= (void *)-1)
5156 sameval_base
= get_addr_base_and_unit_offset
5157 (TREE_OPERAND (sameval
, 0), &soff
);
5159 sameval_base
= (tree
)(void *)-1;
5160 else if ((get_addr_base_and_unit_offset
5161 (TREE_OPERAND (def
, 0), &doff
) == sameval_base
)
5162 && known_eq (soff
, doff
))
5165 sameval
= NULL_TREE
;
5170 /* If the value we want to use is flowing over the backedge and we
5171 should take it as VARYING but it has a non-VARYING value drop to
5173 If we value-number a virtual operand never value-number to the
5174 value from the backedge as that confuses the alias-walking code.
5175 See gcc.dg/torture/pr87176.c. If the value is the same on a
5176 non-backedge everything is OK though. */
5179 && !seen_non_backedge
5180 && TREE_CODE (backedge_val
) == SSA_NAME
5181 && sameval
== backedge_val
5182 && (SSA_NAME_IS_VIRTUAL_OPERAND (backedge_val
)
5183 || SSA_VAL (backedge_val
) != backedge_val
))
5184 /* Do not value-number a virtual operand to sth not visited though
5185 given that allows us to escape a region in alias walking. */
5187 && TREE_CODE (sameval
) == SSA_NAME
5188 && !SSA_NAME_IS_DEFAULT_DEF (sameval
)
5189 && SSA_NAME_IS_VIRTUAL_OPERAND (sameval
)
5190 && (SSA_VAL (sameval
, &visited_p
), !visited_p
)))
5191 /* Note this just drops to VARYING without inserting the PHI into
5193 result
= PHI_RESULT (phi
);
5194 /* If none of the edges was executable keep the value-number at VN_TOP,
5195 if only a single edge is exectuable use its value. */
5196 else if (n_executable
<= 1)
5197 result
= seen_undef
? seen_undef
: sameval
;
5198 /* If we saw only undefined values and VN_TOP use one of the
5199 undefined values. */
5200 else if (sameval
== VN_TOP
)
5201 result
= seen_undef
? seen_undef
: sameval
;
5202 /* First see if it is equivalent to a phi node in this block. We prefer
5203 this as it allows IV elimination - see PRs 66502 and 67167. */
5204 else if ((result
= vn_phi_lookup (phi
, backedges_varying_p
)))
5207 && TREE_CODE (result
) == SSA_NAME
5208 && gimple_code (SSA_NAME_DEF_STMT (result
)) == GIMPLE_PHI
)
5210 gimple_set_plf (SSA_NAME_DEF_STMT (result
), GF_PLF_1
, true);
5211 if (dump_file
&& (dump_flags
& TDF_DETAILS
))
5213 fprintf (dump_file
, "Marking CSEd to PHI node ");
5214 print_gimple_expr (dump_file
, SSA_NAME_DEF_STMT (result
),
5216 fprintf (dump_file
, "\n");
5220 /* If all values are the same use that, unless we've seen undefined
5221 values as well and the value isn't constant.
5222 CCP/copyprop have the same restriction to not remove uninit warnings. */
5224 && (! seen_undef
|| is_gimple_min_invariant (sameval
)))
5228 result
= PHI_RESULT (phi
);
5229 /* Only insert PHIs that are varying, for constant value numbers
5230 we mess up equivalences otherwise as we are only comparing
5231 the immediate controlling predicates. */
5232 vn_phi_insert (phi
, result
, backedges_varying_p
);
5237 return set_ssa_val_to (PHI_RESULT (phi
), result
);
5240 /* Try to simplify RHS using equivalences and constant folding. */
5243 try_to_simplify (gassign
*stmt
)
5245 enum tree_code code
= gimple_assign_rhs_code (stmt
);
5248 /* For stores we can end up simplifying a SSA_NAME rhs. Just return
5249 in this case, there is no point in doing extra work. */
5250 if (code
== SSA_NAME
)
5253 /* First try constant folding based on our current lattice. */
5254 mprts_hook
= vn_lookup_simplify_result
;
5255 tem
= gimple_fold_stmt_to_constant_1 (stmt
, vn_valueize
, vn_valueize
);
5258 && (TREE_CODE (tem
) == SSA_NAME
5259 || is_gimple_min_invariant (tem
)))
5265 /* Visit and value number STMT, return true if the value number
5269 visit_stmt (gimple
*stmt
, bool backedges_varying_p
= false)
5271 bool changed
= false;
5273 if (dump_file
&& (dump_flags
& TDF_DETAILS
))
5275 fprintf (dump_file
, "Value numbering stmt = ");
5276 print_gimple_stmt (dump_file
, stmt
, 0);
5279 if (gimple_code (stmt
) == GIMPLE_PHI
)
5280 changed
= visit_phi (stmt
, NULL
, backedges_varying_p
);
5281 else if (gimple_has_volatile_ops (stmt
))
5282 changed
= defs_to_varying (stmt
);
5283 else if (gassign
*ass
= dyn_cast
<gassign
*> (stmt
))
5285 enum tree_code code
= gimple_assign_rhs_code (ass
);
5286 tree lhs
= gimple_assign_lhs (ass
);
5287 tree rhs1
= gimple_assign_rhs1 (ass
);
5290 /* Shortcut for copies. Simplifying copies is pointless,
5291 since we copy the expression and value they represent. */
5292 if (code
== SSA_NAME
5293 && TREE_CODE (lhs
) == SSA_NAME
)
5295 changed
= visit_copy (lhs
, rhs1
);
5298 simplified
= try_to_simplify (ass
);
5301 if (dump_file
&& (dump_flags
& TDF_DETAILS
))
5303 fprintf (dump_file
, "RHS ");
5304 print_gimple_expr (dump_file
, ass
, 0);
5305 fprintf (dump_file
, " simplified to ");
5306 print_generic_expr (dump_file
, simplified
);
5307 fprintf (dump_file
, "\n");
5310 /* Setting value numbers to constants will occasionally
5311 screw up phi congruence because constants are not
5312 uniquely associated with a single ssa name that can be
5315 && is_gimple_min_invariant (simplified
)
5316 && TREE_CODE (lhs
) == SSA_NAME
)
5318 changed
= set_ssa_val_to (lhs
, simplified
);
5322 && TREE_CODE (simplified
) == SSA_NAME
5323 && TREE_CODE (lhs
) == SSA_NAME
)
5325 changed
= visit_copy (lhs
, simplified
);
5329 if ((TREE_CODE (lhs
) == SSA_NAME
5330 /* We can substitute SSA_NAMEs that are live over
5331 abnormal edges with their constant value. */
5332 && !(gimple_assign_copy_p (ass
)
5333 && is_gimple_min_invariant (rhs1
))
5335 && is_gimple_min_invariant (simplified
))
5336 && SSA_NAME_OCCURS_IN_ABNORMAL_PHI (lhs
))
5337 /* Stores or copies from SSA_NAMEs that are live over
5338 abnormal edges are a problem. */
5339 || (code
== SSA_NAME
5340 && SSA_NAME_OCCURS_IN_ABNORMAL_PHI (rhs1
)))
5341 changed
= defs_to_varying (ass
);
5342 else if (REFERENCE_CLASS_P (lhs
)
5344 changed
= visit_reference_op_store (lhs
, rhs1
, ass
);
5345 else if (TREE_CODE (lhs
) == SSA_NAME
)
5347 if ((gimple_assign_copy_p (ass
)
5348 && is_gimple_min_invariant (rhs1
))
5350 && is_gimple_min_invariant (simplified
)))
5353 changed
= set_ssa_val_to (lhs
, simplified
);
5355 changed
= set_ssa_val_to (lhs
, rhs1
);
5359 /* Visit the original statement. */
5360 switch (vn_get_stmt_kind (ass
))
5363 changed
= visit_nary_op (lhs
, ass
);
5366 changed
= visit_reference_op_load (lhs
, rhs1
, ass
);
5369 changed
= defs_to_varying (ass
);
5375 changed
= defs_to_varying (ass
);
5377 else if (gcall
*call_stmt
= dyn_cast
<gcall
*> (stmt
))
5379 tree lhs
= gimple_call_lhs (call_stmt
);
5380 if (lhs
&& TREE_CODE (lhs
) == SSA_NAME
)
5382 /* Try constant folding based on our current lattice. */
5383 tree simplified
= gimple_fold_stmt_to_constant_1 (call_stmt
,
5387 if (dump_file
&& (dump_flags
& TDF_DETAILS
))
5389 fprintf (dump_file
, "call ");
5390 print_gimple_expr (dump_file
, call_stmt
, 0);
5391 fprintf (dump_file
, " simplified to ");
5392 print_generic_expr (dump_file
, simplified
);
5393 fprintf (dump_file
, "\n");
5396 /* Setting value numbers to constants will occasionally
5397 screw up phi congruence because constants are not
5398 uniquely associated with a single ssa name that can be
5401 && is_gimple_min_invariant (simplified
))
5403 changed
= set_ssa_val_to (lhs
, simplified
);
5404 if (gimple_vdef (call_stmt
))
5405 changed
|= set_ssa_val_to (gimple_vdef (call_stmt
),
5406 SSA_VAL (gimple_vuse (call_stmt
)));
5410 && TREE_CODE (simplified
) == SSA_NAME
)
5412 changed
= visit_copy (lhs
, simplified
);
5413 if (gimple_vdef (call_stmt
))
5414 changed
|= set_ssa_val_to (gimple_vdef (call_stmt
),
5415 SSA_VAL (gimple_vuse (call_stmt
)));
5418 else if (SSA_NAME_OCCURS_IN_ABNORMAL_PHI (lhs
))
5420 changed
= defs_to_varying (call_stmt
);
5425 /* Pick up flags from a devirtualization target. */
5426 tree fn
= gimple_call_fn (stmt
);
5427 int extra_fnflags
= 0;
5428 if (fn
&& TREE_CODE (fn
) == SSA_NAME
)
5431 if (TREE_CODE (fn
) == ADDR_EXPR
5432 && TREE_CODE (TREE_OPERAND (fn
, 0)) == FUNCTION_DECL
)
5433 extra_fnflags
= flags_from_decl_or_type (TREE_OPERAND (fn
, 0));
5435 if (!gimple_call_internal_p (call_stmt
)
5436 && (/* Calls to the same function with the same vuse
5437 and the same operands do not necessarily return the same
5438 value, unless they're pure or const. */
5439 ((gimple_call_flags (call_stmt
) | extra_fnflags
)
5440 & (ECF_PURE
| ECF_CONST
))
5441 /* If calls have a vdef, subsequent calls won't have
5442 the same incoming vuse. So, if 2 calls with vdef have the
5443 same vuse, we know they're not subsequent.
5444 We can value number 2 calls to the same function with the
5445 same vuse and the same operands which are not subsequent
5446 the same, because there is no code in the program that can
5447 compare the 2 values... */
5448 || (gimple_vdef (call_stmt
)
5449 /* ... unless the call returns a pointer which does
5450 not alias with anything else. In which case the
5451 information that the values are distinct are encoded
5453 && !(gimple_call_return_flags (call_stmt
) & ERF_NOALIAS
)
5454 /* Only perform the following when being called from PRE
5455 which embeds tail merging. */
5456 && default_vn_walk_kind
== VN_WALK
)))
5457 changed
= visit_reference_op_call (lhs
, call_stmt
);
5459 changed
= defs_to_varying (call_stmt
);
5462 changed
= defs_to_varying (stmt
);
5468 /* Allocate a value number table. */
5471 allocate_vn_table (vn_tables_t table
, unsigned size
)
5473 table
->phis
= new vn_phi_table_type (size
);
5474 table
->nary
= new vn_nary_op_table_type (size
);
5475 table
->references
= new vn_reference_table_type (size
);
5478 /* Free a value number table. */
5481 free_vn_table (vn_tables_t table
)
5483 /* Walk over elements and release vectors. */
5484 vn_reference_iterator_type hir
;
5486 FOR_EACH_HASH_TABLE_ELEMENT (*table
->references
, vr
, vn_reference_t
, hir
)
5487 vr
->operands
.release ();
5492 delete table
->references
;
5493 table
->references
= NULL
;
5496 /* Set *ID according to RESULT. */
5499 set_value_id_for_result (tree result
, unsigned int *id
)
5501 if (result
&& TREE_CODE (result
) == SSA_NAME
)
5502 *id
= VN_INFO (result
)->value_id
;
5503 else if (result
&& is_gimple_min_invariant (result
))
5504 *id
= get_or_alloc_constant_value_id (result
);
5506 *id
= get_next_value_id ();
5509 /* Set the value ids in the valid hash tables. */
5512 set_hashtable_value_ids (void)
5514 vn_nary_op_iterator_type hin
;
5515 vn_phi_iterator_type hip
;
5516 vn_reference_iterator_type hir
;
5521 /* Now set the value ids of the things we had put in the hash
5524 FOR_EACH_HASH_TABLE_ELEMENT (*valid_info
->nary
, vno
, vn_nary_op_t
, hin
)
5525 if (! vno
->predicated_values
)
5526 set_value_id_for_result (vno
->u
.result
, &vno
->value_id
);
5528 FOR_EACH_HASH_TABLE_ELEMENT (*valid_info
->phis
, vp
, vn_phi_t
, hip
)
5529 set_value_id_for_result (vp
->result
, &vp
->value_id
);
5531 FOR_EACH_HASH_TABLE_ELEMENT (*valid_info
->references
, vr
, vn_reference_t
,
5533 set_value_id_for_result (vr
->result
, &vr
->value_id
);
5536 /* Return the maximum value id we have ever seen. */
5539 get_max_value_id (void)
5541 return next_value_id
;
5544 /* Return the next unique value id. */
5547 get_next_value_id (void)
5549 return next_value_id
++;
5553 /* Compare two expressions E1 and E2 and return true if they are equal. */
5556 expressions_equal_p (tree e1
, tree e2
)
5558 /* The obvious case. */
5562 /* If either one is VN_TOP consider them equal. */
5563 if (e1
== VN_TOP
|| e2
== VN_TOP
)
5566 /* If only one of them is null, they cannot be equal. */
5570 /* Now perform the actual comparison. */
5571 if (TREE_CODE (e1
) == TREE_CODE (e2
)
5572 && operand_equal_p (e1
, e2
, OEP_PURE_SAME
))
5579 /* Return true if the nary operation NARY may trap. This is a copy
5580 of stmt_could_throw_1_p adjusted to the SCCVN IL. */
5583 vn_nary_may_trap (vn_nary_op_t nary
)
5586 tree rhs2
= NULL_TREE
;
5587 bool honor_nans
= false;
5588 bool honor_snans
= false;
5589 bool fp_operation
= false;
5590 bool honor_trapv
= false;
5594 if (TREE_CODE_CLASS (nary
->opcode
) == tcc_comparison
5595 || TREE_CODE_CLASS (nary
->opcode
) == tcc_unary
5596 || TREE_CODE_CLASS (nary
->opcode
) == tcc_binary
)
5599 fp_operation
= FLOAT_TYPE_P (type
);
5602 honor_nans
= flag_trapping_math
&& !flag_finite_math_only
;
5603 honor_snans
= flag_signaling_nans
!= 0;
5605 else if (INTEGRAL_TYPE_P (type
) && TYPE_OVERFLOW_TRAPS (type
))
5608 if (nary
->length
>= 2)
5610 ret
= operation_could_trap_helper_p (nary
->opcode
, fp_operation
,
5611 honor_trapv
, honor_nans
, honor_snans
,
5616 for (i
= 0; i
< nary
->length
; ++i
)
5617 if (tree_could_trap_p (nary
->op
[i
]))
5623 /* Return true if the reference operation REF may trap. */
5626 vn_reference_may_trap (vn_reference_t ref
)
5628 switch (ref
->operands
[0].opcode
)
5632 /* We do not handle calls. */
5634 /* And toplevel address computations never trap. */
5639 vn_reference_op_t op
;
5641 FOR_EACH_VEC_ELT (ref
->operands
, i
, op
)
5645 case WITH_SIZE_EXPR
:
5646 case TARGET_MEM_REF
:
5647 /* Always variable. */
5650 if (op
->op1
&& TREE_CODE (op
->op1
) == SSA_NAME
)
5653 case ARRAY_RANGE_REF
:
5655 if (TREE_CODE (op
->op0
) == SSA_NAME
)
5659 /* Nothing interesting in itself, the base is separate. */
5661 /* The following are the address bases. */
5666 return tree_could_trap_p (TREE_OPERAND (op
->op0
, 0));
5674 eliminate_dom_walker::eliminate_dom_walker (cdi_direction direction
,
5675 bitmap inserted_exprs_
)
5676 : dom_walker (direction
), do_pre (inserted_exprs_
!= NULL
),
5677 el_todo (0), eliminations (0), insertions (0),
5678 inserted_exprs (inserted_exprs_
)
5680 need_eh_cleanup
= BITMAP_ALLOC (NULL
);
5681 need_ab_cleanup
= BITMAP_ALLOC (NULL
);
5684 eliminate_dom_walker::~eliminate_dom_walker ()
5686 BITMAP_FREE (need_eh_cleanup
);
5687 BITMAP_FREE (need_ab_cleanup
);
5690 /* Return a leader for OP that is available at the current point of the
5691 eliminate domwalk. */
5694 eliminate_dom_walker::eliminate_avail (basic_block
, tree op
)
5696 tree valnum
= VN_INFO (op
)->valnum
;
5697 if (TREE_CODE (valnum
) == SSA_NAME
)
5699 if (SSA_NAME_IS_DEFAULT_DEF (valnum
))
5701 if (avail
.length () > SSA_NAME_VERSION (valnum
))
5702 return avail
[SSA_NAME_VERSION (valnum
)];
5704 else if (is_gimple_min_invariant (valnum
))
5709 /* At the current point of the eliminate domwalk make OP available. */
5712 eliminate_dom_walker::eliminate_push_avail (basic_block
, tree op
)
5714 tree valnum
= VN_INFO (op
)->valnum
;
5715 if (TREE_CODE (valnum
) == SSA_NAME
)
5717 if (avail
.length () <= SSA_NAME_VERSION (valnum
))
5718 avail
.safe_grow_cleared (SSA_NAME_VERSION (valnum
) + 1, true);
5720 if (avail
[SSA_NAME_VERSION (valnum
)])
5721 pushop
= avail
[SSA_NAME_VERSION (valnum
)];
5722 avail_stack
.safe_push (pushop
);
5723 avail
[SSA_NAME_VERSION (valnum
)] = op
;
5727 /* Insert the expression recorded by SCCVN for VAL at *GSI. Returns
5728 the leader for the expression if insertion was successful. */
5731 eliminate_dom_walker::eliminate_insert (basic_block bb
,
5732 gimple_stmt_iterator
*gsi
, tree val
)
5734 /* We can insert a sequence with a single assignment only. */
5735 gimple_seq stmts
= VN_INFO (val
)->expr
;
5736 if (!gimple_seq_singleton_p (stmts
))
5738 gassign
*stmt
= dyn_cast
<gassign
*> (gimple_seq_first_stmt (stmts
));
5740 || (!CONVERT_EXPR_CODE_P (gimple_assign_rhs_code (stmt
))
5741 && gimple_assign_rhs_code (stmt
) != VIEW_CONVERT_EXPR
5742 && gimple_assign_rhs_code (stmt
) != BIT_FIELD_REF
5743 && (gimple_assign_rhs_code (stmt
) != BIT_AND_EXPR
5744 || TREE_CODE (gimple_assign_rhs2 (stmt
)) != INTEGER_CST
)))
5747 tree op
= gimple_assign_rhs1 (stmt
);
5748 if (gimple_assign_rhs_code (stmt
) == VIEW_CONVERT_EXPR
5749 || gimple_assign_rhs_code (stmt
) == BIT_FIELD_REF
)
5750 op
= TREE_OPERAND (op
, 0);
5751 tree leader
= TREE_CODE (op
) == SSA_NAME
? eliminate_avail (bb
, op
) : op
;
5757 if (gimple_assign_rhs_code (stmt
) == BIT_FIELD_REF
)
5758 res
= gimple_build (&stmts
, BIT_FIELD_REF
,
5759 TREE_TYPE (val
), leader
,
5760 TREE_OPERAND (gimple_assign_rhs1 (stmt
), 1),
5761 TREE_OPERAND (gimple_assign_rhs1 (stmt
), 2));
5762 else if (gimple_assign_rhs_code (stmt
) == BIT_AND_EXPR
)
5763 res
= gimple_build (&stmts
, BIT_AND_EXPR
,
5764 TREE_TYPE (val
), leader
, gimple_assign_rhs2 (stmt
));
5766 res
= gimple_build (&stmts
, gimple_assign_rhs_code (stmt
),
5767 TREE_TYPE (val
), leader
);
5768 if (TREE_CODE (res
) != SSA_NAME
5769 || SSA_NAME_IS_DEFAULT_DEF (res
)
5770 || gimple_bb (SSA_NAME_DEF_STMT (res
)))
5772 gimple_seq_discard (stmts
);
5774 /* During propagation we have to treat SSA info conservatively
5775 and thus we can end up simplifying the inserted expression
5776 at elimination time to sth not defined in stmts. */
5777 /* But then this is a redundancy we failed to detect. Which means
5778 res now has two values. That doesn't play well with how
5779 we track availability here, so give up. */
5780 if (dump_file
&& (dump_flags
& TDF_DETAILS
))
5782 if (TREE_CODE (res
) == SSA_NAME
)
5783 res
= eliminate_avail (bb
, res
);
5786 fprintf (dump_file
, "Failed to insert expression for value ");
5787 print_generic_expr (dump_file
, val
);
5788 fprintf (dump_file
, " which is really fully redundant to ");
5789 print_generic_expr (dump_file
, res
);
5790 fprintf (dump_file
, "\n");
5798 gsi_insert_seq_before (gsi
, stmts
, GSI_SAME_STMT
);
5799 VN_INFO (res
)->valnum
= val
;
5800 VN_INFO (res
)->visited
= true;
5804 if (dump_file
&& (dump_flags
& TDF_DETAILS
))
5806 fprintf (dump_file
, "Inserted ");
5807 print_gimple_stmt (dump_file
, SSA_NAME_DEF_STMT (res
), 0);
5814 eliminate_dom_walker::eliminate_stmt (basic_block b
, gimple_stmt_iterator
*gsi
)
5816 tree sprime
= NULL_TREE
;
5817 gimple
*stmt
= gsi_stmt (*gsi
);
5818 tree lhs
= gimple_get_lhs (stmt
);
5819 if (lhs
&& TREE_CODE (lhs
) == SSA_NAME
5820 && !gimple_has_volatile_ops (stmt
)
5821 /* See PR43491. Do not replace a global register variable when
5822 it is a the RHS of an assignment. Do replace local register
5823 variables since gcc does not guarantee a local variable will
5824 be allocated in register.
5825 ??? The fix isn't effective here. This should instead
5826 be ensured by not value-numbering them the same but treating
5827 them like volatiles? */
5828 && !(gimple_assign_single_p (stmt
)
5829 && (TREE_CODE (gimple_assign_rhs1 (stmt
)) == VAR_DECL
5830 && DECL_HARD_REGISTER (gimple_assign_rhs1 (stmt
))
5831 && is_global_var (gimple_assign_rhs1 (stmt
)))))
5833 sprime
= eliminate_avail (b
, lhs
);
5836 /* If there is no existing usable leader but SCCVN thinks
5837 it has an expression it wants to use as replacement,
5839 tree val
= VN_INFO (lhs
)->valnum
;
5841 && TREE_CODE (val
) == SSA_NAME
5842 && VN_INFO (val
)->needs_insertion
5843 && VN_INFO (val
)->expr
!= NULL
5844 && (sprime
= eliminate_insert (b
, gsi
, val
)) != NULL_TREE
)
5845 eliminate_push_avail (b
, sprime
);
5848 /* If this now constitutes a copy duplicate points-to
5849 and range info appropriately. This is especially
5850 important for inserted code. See tree-ssa-copy.c
5851 for similar code. */
5853 && TREE_CODE (sprime
) == SSA_NAME
)
5855 basic_block sprime_b
= gimple_bb (SSA_NAME_DEF_STMT (sprime
));
5856 if (POINTER_TYPE_P (TREE_TYPE (lhs
))
5857 && SSA_NAME_PTR_INFO (lhs
)
5858 && ! SSA_NAME_PTR_INFO (sprime
))
5860 duplicate_ssa_name_ptr_info (sprime
,
5861 SSA_NAME_PTR_INFO (lhs
));
5863 reset_flow_sensitive_info (sprime
);
5865 else if (INTEGRAL_TYPE_P (TREE_TYPE (lhs
))
5866 && SSA_NAME_RANGE_INFO (lhs
)
5867 && ! SSA_NAME_RANGE_INFO (sprime
)
5869 duplicate_ssa_name_range_info (sprime
,
5870 SSA_NAME_RANGE_TYPE (lhs
),
5871 SSA_NAME_RANGE_INFO (lhs
));
5874 /* Inhibit the use of an inserted PHI on a loop header when
5875 the address of the memory reference is a simple induction
5876 variable. In other cases the vectorizer won't do anything
5877 anyway (either it's loop invariant or a complicated
5880 && TREE_CODE (sprime
) == SSA_NAME
5882 && (flag_tree_loop_vectorize
|| flag_tree_parallelize_loops
> 1)
5883 && loop_outer (b
->loop_father
)
5884 && has_zero_uses (sprime
)
5885 && bitmap_bit_p (inserted_exprs
, SSA_NAME_VERSION (sprime
))
5886 && gimple_assign_load_p (stmt
))
5888 gimple
*def_stmt
= SSA_NAME_DEF_STMT (sprime
);
5889 basic_block def_bb
= gimple_bb (def_stmt
);
5890 if (gimple_code (def_stmt
) == GIMPLE_PHI
5891 && def_bb
->loop_father
->header
== def_bb
)
5893 loop_p loop
= def_bb
->loop_father
;
5897 FOR_EACH_SSA_TREE_OPERAND (op
, stmt
, iter
, SSA_OP_USE
)
5900 def_bb
= gimple_bb (SSA_NAME_DEF_STMT (op
));
5902 && flow_bb_inside_loop_p (loop
, def_bb
)
5903 && simple_iv (loop
, loop
, op
, &iv
, true))
5911 if (dump_file
&& (dump_flags
& TDF_DETAILS
))
5913 fprintf (dump_file
, "Not replacing ");
5914 print_gimple_expr (dump_file
, stmt
, 0);
5915 fprintf (dump_file
, " with ");
5916 print_generic_expr (dump_file
, sprime
);
5917 fprintf (dump_file
, " which would add a loop"
5918 " carried dependence to loop %d\n",
5921 /* Don't keep sprime available. */
5929 /* If we can propagate the value computed for LHS into
5930 all uses don't bother doing anything with this stmt. */
5931 if (may_propagate_copy (lhs
, sprime
))
5933 /* Mark it for removal. */
5934 to_remove
.safe_push (stmt
);
5936 /* ??? Don't count copy/constant propagations. */
5937 if (gimple_assign_single_p (stmt
)
5938 && (TREE_CODE (gimple_assign_rhs1 (stmt
)) == SSA_NAME
5939 || gimple_assign_rhs1 (stmt
) == sprime
))
5942 if (dump_file
&& (dump_flags
& TDF_DETAILS
))
5944 fprintf (dump_file
, "Replaced ");
5945 print_gimple_expr (dump_file
, stmt
, 0);
5946 fprintf (dump_file
, " with ");
5947 print_generic_expr (dump_file
, sprime
);
5948 fprintf (dump_file
, " in all uses of ");
5949 print_gimple_stmt (dump_file
, stmt
, 0);
5956 /* If this is an assignment from our leader (which
5957 happens in the case the value-number is a constant)
5958 then there is nothing to do. Likewise if we run into
5959 inserted code that needed a conversion because of
5960 our type-agnostic value-numbering of loads. */
5961 if ((gimple_assign_single_p (stmt
)
5962 || (is_gimple_assign (stmt
)
5963 && (CONVERT_EXPR_CODE_P (gimple_assign_rhs_code (stmt
))
5964 || gimple_assign_rhs_code (stmt
) == VIEW_CONVERT_EXPR
)))
5965 && sprime
== gimple_assign_rhs1 (stmt
))
5968 /* Else replace its RHS. */
5969 if (dump_file
&& (dump_flags
& TDF_DETAILS
))
5971 fprintf (dump_file
, "Replaced ");
5972 print_gimple_expr (dump_file
, stmt
, 0);
5973 fprintf (dump_file
, " with ");
5974 print_generic_expr (dump_file
, sprime
);
5975 fprintf (dump_file
, " in ");
5976 print_gimple_stmt (dump_file
, stmt
, 0);
5980 bool can_make_abnormal_goto
= (is_gimple_call (stmt
)
5981 && stmt_can_make_abnormal_goto (stmt
));
5982 gimple
*orig_stmt
= stmt
;
5983 if (!useless_type_conversion_p (TREE_TYPE (lhs
),
5984 TREE_TYPE (sprime
)))
5986 /* We preserve conversions to but not from function or method
5987 types. This asymmetry makes it necessary to re-instantiate
5988 conversions here. */
5989 if (POINTER_TYPE_P (TREE_TYPE (lhs
))
5990 && FUNC_OR_METHOD_TYPE_P (TREE_TYPE (TREE_TYPE (lhs
))))
5991 sprime
= fold_convert (TREE_TYPE (lhs
), sprime
);
5995 tree vdef
= gimple_vdef (stmt
);
5996 tree vuse
= gimple_vuse (stmt
);
5997 propagate_tree_value_into_stmt (gsi
, sprime
);
5998 stmt
= gsi_stmt (*gsi
);
6000 /* In case the VDEF on the original stmt was released, value-number
6001 it to the VUSE. This is to make vuse_ssa_val able to skip
6002 released virtual operands. */
6003 if (vdef
!= gimple_vdef (stmt
))
6005 gcc_assert (SSA_NAME_IN_FREE_LIST (vdef
));
6006 VN_INFO (vdef
)->valnum
= vuse
;
6009 /* If we removed EH side-effects from the statement, clean
6010 its EH information. */
6011 if (maybe_clean_or_replace_eh_stmt (orig_stmt
, stmt
))
6013 bitmap_set_bit (need_eh_cleanup
,
6014 gimple_bb (stmt
)->index
);
6015 if (dump_file
&& (dump_flags
& TDF_DETAILS
))
6016 fprintf (dump_file
, " Removed EH side-effects.\n");
6019 /* Likewise for AB side-effects. */
6020 if (can_make_abnormal_goto
6021 && !stmt_can_make_abnormal_goto (stmt
))
6023 bitmap_set_bit (need_ab_cleanup
,
6024 gimple_bb (stmt
)->index
);
6025 if (dump_file
&& (dump_flags
& TDF_DETAILS
))
6026 fprintf (dump_file
, " Removed AB side-effects.\n");
6033 /* If the statement is a scalar store, see if the expression
6034 has the same value number as its rhs. If so, the store is
6036 if (gimple_assign_single_p (stmt
)
6037 && !gimple_has_volatile_ops (stmt
)
6038 && !is_gimple_reg (gimple_assign_lhs (stmt
))
6039 && (TREE_CODE (gimple_assign_rhs1 (stmt
)) == SSA_NAME
6040 || is_gimple_min_invariant (gimple_assign_rhs1 (stmt
))))
6042 tree rhs
= gimple_assign_rhs1 (stmt
);
6043 vn_reference_t vnresult
;
6044 /* ??? gcc.dg/torture/pr91445.c shows that we lookup a boolean
6045 typed load of a byte known to be 0x11 as 1 so a store of
6046 a boolean 1 is detected as redundant. Because of this we
6047 have to make sure to lookup with a ref where its size
6048 matches the precision. */
6049 tree lookup_lhs
= lhs
;
6050 if (INTEGRAL_TYPE_P (TREE_TYPE (lhs
))
6051 && (TREE_CODE (lhs
) != COMPONENT_REF
6052 || !DECL_BIT_FIELD_TYPE (TREE_OPERAND (lhs
, 1)))
6053 && !type_has_mode_precision_p (TREE_TYPE (lhs
)))
6055 if (TREE_CODE (lhs
) == COMPONENT_REF
6056 || TREE_CODE (lhs
) == MEM_REF
)
6058 tree ltype
= build_nonstandard_integer_type
6059 (TREE_INT_CST_LOW (TYPE_SIZE (TREE_TYPE (lhs
))),
6060 TYPE_UNSIGNED (TREE_TYPE (lhs
)));
6061 if (TREE_CODE (lhs
) == COMPONENT_REF
)
6063 tree foff
= component_ref_field_offset (lhs
);
6064 tree f
= TREE_OPERAND (lhs
, 1);
6065 if (!poly_int_tree_p (foff
))
6066 lookup_lhs
= NULL_TREE
;
6068 lookup_lhs
= build3 (BIT_FIELD_REF
, ltype
,
6069 TREE_OPERAND (lhs
, 0),
6070 TYPE_SIZE (TREE_TYPE (lhs
)),
6072 (foff
, DECL_FIELD_BIT_OFFSET (f
)));
6075 lookup_lhs
= build2 (MEM_REF
, ltype
,
6076 TREE_OPERAND (lhs
, 0),
6077 TREE_OPERAND (lhs
, 1));
6080 lookup_lhs
= NULL_TREE
;
6082 tree val
= NULL_TREE
;
6084 val
= vn_reference_lookup (lookup_lhs
, gimple_vuse (stmt
),
6085 VN_WALKREWRITE
, &vnresult
, false);
6086 if (TREE_CODE (rhs
) == SSA_NAME
)
6087 rhs
= VN_INFO (rhs
)->valnum
;
6089 && (operand_equal_p (val
, rhs
, 0)
6090 /* Due to the bitfield lookups above we can get bit
6091 interpretations of the same RHS as values here. Those
6092 are redundant as well. */
6093 || (TREE_CODE (val
) == SSA_NAME
6094 && gimple_assign_single_p (SSA_NAME_DEF_STMT (val
))
6095 && (val
= gimple_assign_rhs1 (SSA_NAME_DEF_STMT (val
)))
6096 && TREE_CODE (val
) == VIEW_CONVERT_EXPR
6097 && TREE_OPERAND (val
, 0) == rhs
)))
6099 /* We can only remove the later store if the former aliases
6100 at least all accesses the later one does or if the store
6101 was to readonly memory storing the same value. */
6103 ao_ref_init (&lhs_ref
, lhs
);
6104 alias_set_type set
= ao_ref_alias_set (&lhs_ref
);
6105 alias_set_type base_set
= ao_ref_base_alias_set (&lhs_ref
);
6107 || ((vnresult
->set
== set
6108 || alias_set_subset_of (set
, vnresult
->set
))
6109 && (vnresult
->base_set
== base_set
6110 || alias_set_subset_of (base_set
, vnresult
->base_set
))))
6112 if (dump_file
&& (dump_flags
& TDF_DETAILS
))
6114 fprintf (dump_file
, "Deleted redundant store ");
6115 print_gimple_stmt (dump_file
, stmt
, 0);
6118 /* Queue stmt for removal. */
6119 to_remove
.safe_push (stmt
);
6125 /* If this is a control statement value numbering left edges
6126 unexecuted on force the condition in a way consistent with
6128 if (gcond
*cond
= dyn_cast
<gcond
*> (stmt
))
6130 if ((EDGE_SUCC (b
, 0)->flags
& EDGE_EXECUTABLE
)
6131 ^ (EDGE_SUCC (b
, 1)->flags
& EDGE_EXECUTABLE
))
6133 if (dump_file
&& (dump_flags
& TDF_DETAILS
))
6135 fprintf (dump_file
, "Removing unexecutable edge from ");
6136 print_gimple_stmt (dump_file
, stmt
, 0);
6138 if (((EDGE_SUCC (b
, 0)->flags
& EDGE_TRUE_VALUE
) != 0)
6139 == ((EDGE_SUCC (b
, 0)->flags
& EDGE_EXECUTABLE
) != 0))
6140 gimple_cond_make_true (cond
);
6142 gimple_cond_make_false (cond
);
6144 el_todo
|= TODO_cleanup_cfg
;
6149 bool can_make_abnormal_goto
= stmt_can_make_abnormal_goto (stmt
);
6150 bool was_noreturn
= (is_gimple_call (stmt
)
6151 && gimple_call_noreturn_p (stmt
));
6152 tree vdef
= gimple_vdef (stmt
);
6153 tree vuse
= gimple_vuse (stmt
);
6155 /* If we didn't replace the whole stmt (or propagate the result
6156 into all uses), replace all uses on this stmt with their
6158 bool modified
= false;
6159 use_operand_p use_p
;
6161 FOR_EACH_SSA_USE_OPERAND (use_p
, stmt
, iter
, SSA_OP_USE
)
6163 tree use
= USE_FROM_PTR (use_p
);
6164 /* ??? The call code above leaves stmt operands un-updated. */
6165 if (TREE_CODE (use
) != SSA_NAME
)
6168 if (SSA_NAME_IS_DEFAULT_DEF (use
))
6169 /* ??? For default defs BB shouldn't matter, but we have to
6170 solve the inconsistency between rpo eliminate and
6171 dom eliminate avail valueization first. */
6172 sprime
= eliminate_avail (b
, use
);
6174 /* Look for sth available at the definition block of the argument.
6175 This avoids inconsistencies between availability there which
6176 decides if the stmt can be removed and availability at the
6177 use site. The SSA property ensures that things available
6178 at the definition are also available at uses. */
6179 sprime
= eliminate_avail (gimple_bb (SSA_NAME_DEF_STMT (use
)), use
);
6180 if (sprime
&& sprime
!= use
6181 && may_propagate_copy (use
, sprime
)
6182 /* We substitute into debug stmts to avoid excessive
6183 debug temporaries created by removed stmts, but we need
6184 to avoid doing so for inserted sprimes as we never want
6185 to create debug temporaries for them. */
6187 || TREE_CODE (sprime
) != SSA_NAME
6188 || !is_gimple_debug (stmt
)
6189 || !bitmap_bit_p (inserted_exprs
, SSA_NAME_VERSION (sprime
))))
6191 propagate_value (use_p
, sprime
);
6196 /* Fold the stmt if modified, this canonicalizes MEM_REFs we propagated
6197 into which is a requirement for the IPA devirt machinery. */
6198 gimple
*old_stmt
= stmt
;
6201 /* If a formerly non-invariant ADDR_EXPR is turned into an
6202 invariant one it was on a separate stmt. */
6203 if (gimple_assign_single_p (stmt
)
6204 && TREE_CODE (gimple_assign_rhs1 (stmt
)) == ADDR_EXPR
)
6205 recompute_tree_invariant_for_addr_expr (gimple_assign_rhs1 (stmt
));
6206 gimple_stmt_iterator prev
= *gsi
;
6208 if (fold_stmt (gsi
))
6210 /* fold_stmt may have created new stmts inbetween
6211 the previous stmt and the folded stmt. Mark
6212 all defs created there as varying to not confuse
6213 the SCCVN machinery as we're using that even during
6215 if (gsi_end_p (prev
))
6216 prev
= gsi_start_bb (b
);
6219 if (gsi_stmt (prev
) != gsi_stmt (*gsi
))
6224 FOR_EACH_SSA_TREE_OPERAND (def
, gsi_stmt (prev
),
6225 dit
, SSA_OP_ALL_DEFS
)
6226 /* As existing DEFs may move between stmts
6227 only process new ones. */
6228 if (! has_VN_INFO (def
))
6230 VN_INFO (def
)->valnum
= def
;
6231 VN_INFO (def
)->visited
= true;
6233 if (gsi_stmt (prev
) == gsi_stmt (*gsi
))
6239 stmt
= gsi_stmt (*gsi
);
6240 /* In case we folded the stmt away schedule the NOP for removal. */
6241 if (gimple_nop_p (stmt
))
6242 to_remove
.safe_push (stmt
);
6245 /* Visit indirect calls and turn them into direct calls if
6246 possible using the devirtualization machinery. Do this before
6247 checking for required EH/abnormal/noreturn cleanup as devird
6248 may expose more of those. */
6249 if (gcall
*call_stmt
= dyn_cast
<gcall
*> (stmt
))
6251 tree fn
= gimple_call_fn (call_stmt
);
6253 && flag_devirtualize
6254 && virtual_method_call_p (fn
))
6256 tree otr_type
= obj_type_ref_class (fn
);
6257 unsigned HOST_WIDE_INT otr_tok
6258 = tree_to_uhwi (OBJ_TYPE_REF_TOKEN (fn
));
6260 ipa_polymorphic_call_context
context (current_function_decl
,
6261 fn
, stmt
, &instance
);
6262 context
.get_dynamic_type (instance
, OBJ_TYPE_REF_OBJECT (fn
),
6263 otr_type
, stmt
, NULL
);
6265 vec
<cgraph_node
*> targets
6266 = possible_polymorphic_call_targets (obj_type_ref_class (fn
),
6267 otr_tok
, context
, &final
);
6269 dump_possible_polymorphic_call_targets (dump_file
,
6270 obj_type_ref_class (fn
),
6272 if (final
&& targets
.length () <= 1 && dbg_cnt (devirt
))
6275 if (targets
.length () == 1)
6276 fn
= targets
[0]->decl
;
6278 fn
= builtin_decl_implicit (BUILT_IN_UNREACHABLE
);
6279 if (dump_enabled_p ())
6281 dump_printf_loc (MSG_OPTIMIZED_LOCATIONS
, stmt
,
6282 "converting indirect call to "
6284 lang_hooks
.decl_printable_name (fn
, 2));
6286 gimple_call_set_fndecl (call_stmt
, fn
);
6287 /* If changing the call to __builtin_unreachable
6288 or similar noreturn function, adjust gimple_call_fntype
6290 if (gimple_call_noreturn_p (call_stmt
)
6291 && VOID_TYPE_P (TREE_TYPE (TREE_TYPE (fn
)))
6292 && TYPE_ARG_TYPES (TREE_TYPE (fn
))
6293 && (TREE_VALUE (TYPE_ARG_TYPES (TREE_TYPE (fn
)))
6295 gimple_call_set_fntype (call_stmt
, TREE_TYPE (fn
));
6296 maybe_remove_unused_call_args (cfun
, call_stmt
);
6304 /* When changing a call into a noreturn call, cfg cleanup
6305 is needed to fix up the noreturn call. */
6307 && is_gimple_call (stmt
) && gimple_call_noreturn_p (stmt
))
6308 to_fixup
.safe_push (stmt
);
6309 /* When changing a condition or switch into one we know what
6310 edge will be executed, schedule a cfg cleanup. */
6311 if ((gimple_code (stmt
) == GIMPLE_COND
6312 && (gimple_cond_true_p (as_a
<gcond
*> (stmt
))
6313 || gimple_cond_false_p (as_a
<gcond
*> (stmt
))))
6314 || (gimple_code (stmt
) == GIMPLE_SWITCH
6315 && TREE_CODE (gimple_switch_index
6316 (as_a
<gswitch
*> (stmt
))) == INTEGER_CST
))
6317 el_todo
|= TODO_cleanup_cfg
;
6318 /* If we removed EH side-effects from the statement, clean
6319 its EH information. */
6320 if (maybe_clean_or_replace_eh_stmt (old_stmt
, stmt
))
6322 bitmap_set_bit (need_eh_cleanup
,
6323 gimple_bb (stmt
)->index
);
6324 if (dump_file
&& (dump_flags
& TDF_DETAILS
))
6325 fprintf (dump_file
, " Removed EH side-effects.\n");
6327 /* Likewise for AB side-effects. */
6328 if (can_make_abnormal_goto
6329 && !stmt_can_make_abnormal_goto (stmt
))
6331 bitmap_set_bit (need_ab_cleanup
,
6332 gimple_bb (stmt
)->index
);
6333 if (dump_file
&& (dump_flags
& TDF_DETAILS
))
6334 fprintf (dump_file
, " Removed AB side-effects.\n");
6337 /* In case the VDEF on the original stmt was released, value-number
6338 it to the VUSE. This is to make vuse_ssa_val able to skip
6339 released virtual operands. */
6340 if (vdef
&& SSA_NAME_IN_FREE_LIST (vdef
))
6341 VN_INFO (vdef
)->valnum
= vuse
;
6344 /* Make new values available - for fully redundant LHS we
6345 continue with the next stmt above and skip this. */
6347 FOR_EACH_SSA_DEF_OPERAND (defp
, stmt
, iter
, SSA_OP_DEF
)
6348 eliminate_push_avail (b
, DEF_FROM_PTR (defp
));
6351 /* Perform elimination for the basic-block B during the domwalk. */
6354 eliminate_dom_walker::before_dom_children (basic_block b
)
6357 avail_stack
.safe_push (NULL_TREE
);
6359 /* Skip unreachable blocks marked unreachable during the SCCVN domwalk. */
6360 if (!(b
->flags
& BB_EXECUTABLE
))
6365 for (gphi_iterator gsi
= gsi_start_phis (b
); !gsi_end_p (gsi
);)
6367 gphi
*phi
= gsi
.phi ();
6368 tree res
= PHI_RESULT (phi
);
6370 if (virtual_operand_p (res
))
6376 tree sprime
= eliminate_avail (b
, res
);
6380 if (dump_file
&& (dump_flags
& TDF_DETAILS
))
6382 fprintf (dump_file
, "Replaced redundant PHI node defining ");
6383 print_generic_expr (dump_file
, res
);
6384 fprintf (dump_file
, " with ");
6385 print_generic_expr (dump_file
, sprime
);
6386 fprintf (dump_file
, "\n");
6389 /* If we inserted this PHI node ourself, it's not an elimination. */
6390 if (! inserted_exprs
6391 || ! bitmap_bit_p (inserted_exprs
, SSA_NAME_VERSION (res
)))
6394 /* If we will propagate into all uses don't bother to do
6396 if (may_propagate_copy (res
, sprime
))
6398 /* Mark the PHI for removal. */
6399 to_remove
.safe_push (phi
);
6404 remove_phi_node (&gsi
, false);
6406 if (!useless_type_conversion_p (TREE_TYPE (res
), TREE_TYPE (sprime
)))
6407 sprime
= fold_convert (TREE_TYPE (res
), sprime
);
6408 gimple
*stmt
= gimple_build_assign (res
, sprime
);
6409 gimple_stmt_iterator gsi2
= gsi_after_labels (b
);
6410 gsi_insert_before (&gsi2
, stmt
, GSI_NEW_STMT
);
6414 eliminate_push_avail (b
, res
);
6418 for (gimple_stmt_iterator gsi
= gsi_start_bb (b
);
6421 eliminate_stmt (b
, &gsi
);
6423 /* Replace destination PHI arguments. */
6426 FOR_EACH_EDGE (e
, ei
, b
->succs
)
6427 if (e
->flags
& EDGE_EXECUTABLE
)
6428 for (gphi_iterator gsi
= gsi_start_phis (e
->dest
);
6432 gphi
*phi
= gsi
.phi ();
6433 use_operand_p use_p
= PHI_ARG_DEF_PTR_FROM_EDGE (phi
, e
);
6434 tree arg
= USE_FROM_PTR (use_p
);
6435 if (TREE_CODE (arg
) != SSA_NAME
6436 || virtual_operand_p (arg
))
6438 tree sprime
= eliminate_avail (b
, arg
);
6439 if (sprime
&& may_propagate_copy (arg
, sprime
))
6440 propagate_value (use_p
, sprime
);
6443 vn_context_bb
= NULL
;
6448 /* Make no longer available leaders no longer available. */
6451 eliminate_dom_walker::after_dom_children (basic_block
)
6454 while ((entry
= avail_stack
.pop ()) != NULL_TREE
)
6456 tree valnum
= VN_INFO (entry
)->valnum
;
6457 tree old
= avail
[SSA_NAME_VERSION (valnum
)];
6459 avail
[SSA_NAME_VERSION (valnum
)] = NULL_TREE
;
6461 avail
[SSA_NAME_VERSION (valnum
)] = entry
;
6465 /* Remove queued stmts and perform delayed cleanups. */
6468 eliminate_dom_walker::eliminate_cleanup (bool region_p
)
6470 statistics_counter_event (cfun
, "Eliminated", eliminations
);
6471 statistics_counter_event (cfun
, "Insertions", insertions
);
6473 /* We cannot remove stmts during BB walk, especially not release SSA
6474 names there as this confuses the VN machinery. The stmts ending
6475 up in to_remove are either stores or simple copies.
6476 Remove stmts in reverse order to make debug stmt creation possible. */
6477 while (!to_remove
.is_empty ())
6479 bool do_release_defs
= true;
6480 gimple
*stmt
= to_remove
.pop ();
6482 /* When we are value-numbering a region we do not require exit PHIs to
6483 be present so we have to make sure to deal with uses outside of the
6484 region of stmts that we thought are eliminated.
6485 ??? Note we may be confused by uses in dead regions we didn't run
6486 elimination on. Rather than checking individual uses we accept
6487 dead copies to be generated here (gcc.c-torture/execute/20060905-1.c
6488 contains such example). */
6491 if (gphi
*phi
= dyn_cast
<gphi
*> (stmt
))
6493 tree lhs
= gimple_phi_result (phi
);
6494 if (!has_zero_uses (lhs
))
6496 if (dump_file
&& (dump_flags
& TDF_DETAILS
))
6497 fprintf (dump_file
, "Keeping eliminated stmt live "
6498 "as copy because of out-of-region uses\n");
6499 tree sprime
= eliminate_avail (gimple_bb (stmt
), lhs
);
6500 gimple
*copy
= gimple_build_assign (lhs
, sprime
);
6501 gimple_stmt_iterator gsi
6502 = gsi_after_labels (gimple_bb (stmt
));
6503 gsi_insert_before (&gsi
, copy
, GSI_SAME_STMT
);
6504 do_release_defs
= false;
6507 else if (tree lhs
= gimple_get_lhs (stmt
))
6508 if (TREE_CODE (lhs
) == SSA_NAME
6509 && !has_zero_uses (lhs
))
6511 if (dump_file
&& (dump_flags
& TDF_DETAILS
))
6512 fprintf (dump_file
, "Keeping eliminated stmt live "
6513 "as copy because of out-of-region uses\n");
6514 tree sprime
= eliminate_avail (gimple_bb (stmt
), lhs
);
6515 gimple_stmt_iterator gsi
= gsi_for_stmt (stmt
);
6516 if (is_gimple_assign (stmt
))
6518 gimple_assign_set_rhs_from_tree (&gsi
, sprime
);
6519 stmt
= gsi_stmt (gsi
);
6521 if (maybe_clean_or_replace_eh_stmt (stmt
, stmt
))
6522 bitmap_set_bit (need_eh_cleanup
, gimple_bb (stmt
)->index
);
6527 gimple
*copy
= gimple_build_assign (lhs
, sprime
);
6528 gsi_insert_before (&gsi
, copy
, GSI_SAME_STMT
);
6529 do_release_defs
= false;
6534 if (dump_file
&& (dump_flags
& TDF_DETAILS
))
6536 fprintf (dump_file
, "Removing dead stmt ");
6537 print_gimple_stmt (dump_file
, stmt
, 0, TDF_NONE
);
6540 gimple_stmt_iterator gsi
= gsi_for_stmt (stmt
);
6541 if (gimple_code (stmt
) == GIMPLE_PHI
)
6542 remove_phi_node (&gsi
, do_release_defs
);
6545 basic_block bb
= gimple_bb (stmt
);
6546 unlink_stmt_vdef (stmt
);
6547 if (gsi_remove (&gsi
, true))
6548 bitmap_set_bit (need_eh_cleanup
, bb
->index
);
6549 if (is_gimple_call (stmt
) && stmt_can_make_abnormal_goto (stmt
))
6550 bitmap_set_bit (need_ab_cleanup
, bb
->index
);
6551 if (do_release_defs
)
6552 release_defs (stmt
);
6555 /* Removing a stmt may expose a forwarder block. */
6556 el_todo
|= TODO_cleanup_cfg
;
6559 /* Fixup stmts that became noreturn calls. This may require splitting
6560 blocks and thus isn't possible during the dominator walk. Do this
6561 in reverse order so we don't inadvertedly remove a stmt we want to
6562 fixup by visiting a dominating now noreturn call first. */
6563 while (!to_fixup
.is_empty ())
6565 gimple
*stmt
= to_fixup
.pop ();
6567 if (dump_file
&& (dump_flags
& TDF_DETAILS
))
6569 fprintf (dump_file
, "Fixing up noreturn call ");
6570 print_gimple_stmt (dump_file
, stmt
, 0);
6573 if (fixup_noreturn_call (stmt
))
6574 el_todo
|= TODO_cleanup_cfg
;
6577 bool do_eh_cleanup
= !bitmap_empty_p (need_eh_cleanup
);
6578 bool do_ab_cleanup
= !bitmap_empty_p (need_ab_cleanup
);
6581 gimple_purge_all_dead_eh_edges (need_eh_cleanup
);
6584 gimple_purge_all_dead_abnormal_call_edges (need_ab_cleanup
);
6586 if (do_eh_cleanup
|| do_ab_cleanup
)
6587 el_todo
|= TODO_cleanup_cfg
;
6592 /* Eliminate fully redundant computations. */
6595 eliminate_with_rpo_vn (bitmap inserted_exprs
)
6597 eliminate_dom_walker
walker (CDI_DOMINATORS
, inserted_exprs
);
6599 eliminate_dom_walker
*saved_rpo_avail
= rpo_avail
;
6600 rpo_avail
= &walker
;
6601 walker
.walk (cfun
->cfg
->x_entry_block_ptr
);
6602 rpo_avail
= saved_rpo_avail
;
6604 return walker
.eliminate_cleanup ();
6608 do_rpo_vn (function
*fn
, edge entry
, bitmap exit_bbs
,
6609 bool iterate
, bool eliminate
);
6612 run_rpo_vn (vn_lookup_kind kind
)
6614 default_vn_walk_kind
= kind
;
6615 do_rpo_vn (cfun
, NULL
, NULL
, true, false);
6617 /* ??? Prune requirement of these. */
6618 constant_to_value_id
= new hash_table
<vn_constant_hasher
> (23);
6619 constant_value_ids
= BITMAP_ALLOC (NULL
);
6621 /* Initialize the value ids and prune out remaining VN_TOPs
6625 FOR_EACH_SSA_NAME (i
, name
, cfun
)
6627 vn_ssa_aux_t info
= VN_INFO (name
);
6629 || info
->valnum
== VN_TOP
)
6630 info
->valnum
= name
;
6631 if (info
->valnum
== name
)
6632 info
->value_id
= get_next_value_id ();
6633 else if (is_gimple_min_invariant (info
->valnum
))
6634 info
->value_id
= get_or_alloc_constant_value_id (info
->valnum
);
6638 FOR_EACH_SSA_NAME (i
, name
, cfun
)
6640 vn_ssa_aux_t info
= VN_INFO (name
);
6641 if (TREE_CODE (info
->valnum
) == SSA_NAME
6642 && info
->valnum
!= name
6643 && info
->value_id
!= VN_INFO (info
->valnum
)->value_id
)
6644 info
->value_id
= VN_INFO (info
->valnum
)->value_id
;
6647 set_hashtable_value_ids ();
6649 if (dump_file
&& (dump_flags
& TDF_DETAILS
))
6651 fprintf (dump_file
, "Value numbers:\n");
6652 FOR_EACH_SSA_NAME (i
, name
, cfun
)
6654 if (VN_INFO (name
)->visited
6655 && SSA_VAL (name
) != name
)
6657 print_generic_expr (dump_file
, name
);
6658 fprintf (dump_file
, " = ");
6659 print_generic_expr (dump_file
, SSA_VAL (name
));
6660 fprintf (dump_file
, " (%04d)\n", VN_INFO (name
)->value_id
);
6666 /* Free VN associated data structures. */
6671 free_vn_table (valid_info
);
6672 XDELETE (valid_info
);
6673 obstack_free (&vn_tables_obstack
, NULL
);
6674 obstack_free (&vn_tables_insert_obstack
, NULL
);
6676 vn_ssa_aux_iterator_type it
;
6678 FOR_EACH_HASH_TABLE_ELEMENT (*vn_ssa_aux_hash
, info
, vn_ssa_aux_t
, it
)
6679 if (info
->needs_insertion
)
6680 release_ssa_name (info
->name
);
6681 obstack_free (&vn_ssa_aux_obstack
, NULL
);
6682 delete vn_ssa_aux_hash
;
6684 delete constant_to_value_id
;
6685 constant_to_value_id
= NULL
;
6686 BITMAP_FREE (constant_value_ids
);
6689 /* Hook for maybe_push_res_to_seq, lookup the expression in the VN tables. */
6692 vn_lookup_simplify_result (gimple_match_op
*res_op
)
6694 if (!res_op
->code
.is_tree_code ())
6696 tree
*ops
= res_op
->ops
;
6697 unsigned int length
= res_op
->num_ops
;
6698 if (res_op
->code
== CONSTRUCTOR
6699 /* ??? We're arriving here with SCCVNs view, decomposed CONSTRUCTOR
6700 and GIMPLEs / match-and-simplifies, CONSTRUCTOR as GENERIC tree. */
6701 && TREE_CODE (res_op
->ops
[0]) == CONSTRUCTOR
)
6703 length
= CONSTRUCTOR_NELTS (res_op
->ops
[0]);
6704 ops
= XALLOCAVEC (tree
, length
);
6705 for (unsigned i
= 0; i
< length
; ++i
)
6706 ops
[i
] = CONSTRUCTOR_ELT (res_op
->ops
[0], i
)->value
;
6708 vn_nary_op_t vnresult
= NULL
;
6709 tree res
= vn_nary_op_lookup_pieces (length
, (tree_code
) res_op
->code
,
6710 res_op
->type
, ops
, &vnresult
);
6711 /* If this is used from expression simplification make sure to
6712 return an available expression. */
6713 if (res
&& TREE_CODE (res
) == SSA_NAME
&& mprts_hook
&& rpo_avail
)
6714 res
= rpo_avail
->eliminate_avail (vn_context_bb
, res
);
6718 /* Return a leader for OPs value that is valid at BB. */
6721 rpo_elim::eliminate_avail (basic_block bb
, tree op
)
6724 tree valnum
= SSA_VAL (op
, &visited
);
6725 /* If we didn't visit OP then it must be defined outside of the
6726 region we process and also dominate it. So it is available. */
6729 if (TREE_CODE (valnum
) == SSA_NAME
)
6731 if (SSA_NAME_IS_DEFAULT_DEF (valnum
))
6733 vn_avail
*av
= VN_INFO (valnum
)->avail
;
6736 if (av
->location
== bb
->index
)
6737 /* On tramp3d 90% of the cases are here. */
6738 return ssa_name (av
->leader
);
6741 basic_block abb
= BASIC_BLOCK_FOR_FN (cfun
, av
->location
);
6742 /* ??? During elimination we have to use availability at the
6743 definition site of a use we try to replace. This
6744 is required to not run into inconsistencies because
6745 of dominated_by_p_w_unex behavior and removing a definition
6746 while not replacing all uses.
6747 ??? We could try to consistently walk dominators
6748 ignoring non-executable regions. The nearest common
6749 dominator of bb and abb is where we can stop walking. We
6750 may also be able to "pre-compute" (bits of) the next immediate
6751 (non-)dominator during the RPO walk when marking edges as
6753 if (dominated_by_p_w_unex (bb
, abb
))
6755 tree leader
= ssa_name (av
->leader
);
6756 /* Prevent eliminations that break loop-closed SSA. */
6757 if (loops_state_satisfies_p (LOOP_CLOSED_SSA
)
6758 && ! SSA_NAME_IS_DEFAULT_DEF (leader
)
6759 && ! flow_bb_inside_loop_p (gimple_bb (SSA_NAME_DEF_STMT
6760 (leader
))->loop_father
,
6763 if (dump_file
&& (dump_flags
& TDF_DETAILS
))
6765 print_generic_expr (dump_file
, leader
);
6766 fprintf (dump_file
, " is available for ");
6767 print_generic_expr (dump_file
, valnum
);
6768 fprintf (dump_file
, "\n");
6770 /* On tramp3d 99% of the _remaining_ cases succeed at
6774 /* ??? Can we somehow skip to the immediate dominator
6775 RPO index (bb_to_rpo)? Again, maybe not worth, on
6776 tramp3d the worst number of elements in the vector is 9. */
6781 else if (valnum
!= VN_TOP
)
6782 /* valnum is is_gimple_min_invariant. */
6787 /* Make LEADER a leader for its value at BB. */
6790 rpo_elim::eliminate_push_avail (basic_block bb
, tree leader
)
6792 tree valnum
= VN_INFO (leader
)->valnum
;
6793 if (valnum
== VN_TOP
6794 || is_gimple_min_invariant (valnum
))
6796 if (dump_file
&& (dump_flags
& TDF_DETAILS
))
6798 fprintf (dump_file
, "Making available beyond BB%d ", bb
->index
);
6799 print_generic_expr (dump_file
, leader
);
6800 fprintf (dump_file
, " for value ");
6801 print_generic_expr (dump_file
, valnum
);
6802 fprintf (dump_file
, "\n");
6804 vn_ssa_aux_t value
= VN_INFO (valnum
);
6806 if (m_avail_freelist
)
6808 av
= m_avail_freelist
;
6809 m_avail_freelist
= m_avail_freelist
->next
;
6812 av
= XOBNEW (&vn_ssa_aux_obstack
, vn_avail
);
6813 av
->location
= bb
->index
;
6814 av
->leader
= SSA_NAME_VERSION (leader
);
6815 av
->next
= value
->avail
;
6819 /* Valueization hook for RPO VN plus required state. */
6822 rpo_vn_valueize (tree name
)
6824 if (TREE_CODE (name
) == SSA_NAME
)
6826 vn_ssa_aux_t val
= VN_INFO (name
);
6829 tree tem
= val
->valnum
;
6830 if (tem
!= VN_TOP
&& tem
!= name
)
6832 if (TREE_CODE (tem
) != SSA_NAME
)
6834 /* For all values we only valueize to an available leader
6835 which means we can use SSA name info without restriction. */
6836 tem
= rpo_avail
->eliminate_avail (vn_context_bb
, tem
);
6845 /* Insert on PRED_E predicates derived from CODE OPS being true besides the
6846 inverted condition. */
6849 insert_related_predicates_on_edge (enum tree_code code
, tree
*ops
, edge pred_e
)
6854 /* a < b -> a {!,<}= b */
6855 vn_nary_op_insert_pieces_predicated (2, NE_EXPR
, boolean_type_node
,
6856 ops
, boolean_true_node
, 0, pred_e
);
6857 vn_nary_op_insert_pieces_predicated (2, LE_EXPR
, boolean_type_node
,
6858 ops
, boolean_true_node
, 0, pred_e
);
6859 /* a < b -> ! a {>,=} b */
6860 vn_nary_op_insert_pieces_predicated (2, GT_EXPR
, boolean_type_node
,
6861 ops
, boolean_false_node
, 0, pred_e
);
6862 vn_nary_op_insert_pieces_predicated (2, EQ_EXPR
, boolean_type_node
,
6863 ops
, boolean_false_node
, 0, pred_e
);
6866 /* a > b -> a {!,>}= b */
6867 vn_nary_op_insert_pieces_predicated (2, NE_EXPR
, boolean_type_node
,
6868 ops
, boolean_true_node
, 0, pred_e
);
6869 vn_nary_op_insert_pieces_predicated (2, GE_EXPR
, boolean_type_node
,
6870 ops
, boolean_true_node
, 0, pred_e
);
6871 /* a > b -> ! a {<,=} b */
6872 vn_nary_op_insert_pieces_predicated (2, LT_EXPR
, boolean_type_node
,
6873 ops
, boolean_false_node
, 0, pred_e
);
6874 vn_nary_op_insert_pieces_predicated (2, EQ_EXPR
, boolean_type_node
,
6875 ops
, boolean_false_node
, 0, pred_e
);
6878 /* a == b -> ! a {<,>} b */
6879 vn_nary_op_insert_pieces_predicated (2, LT_EXPR
, boolean_type_node
,
6880 ops
, boolean_false_node
, 0, pred_e
);
6881 vn_nary_op_insert_pieces_predicated (2, GT_EXPR
, boolean_type_node
,
6882 ops
, boolean_false_node
, 0, pred_e
);
6887 /* Nothing besides inverted condition. */
6893 /* Main stmt worker for RPO VN, process BB. */
6896 process_bb (rpo_elim
&avail
, basic_block bb
,
6897 bool bb_visited
, bool iterate_phis
, bool iterate
, bool eliminate
,
6898 bool do_region
, bitmap exit_bbs
, bool skip_phis
)
6906 /* If we are in loop-closed SSA preserve this state. This is
6907 relevant when called on regions from outside of FRE/PRE. */
6908 bool lc_phi_nodes
= false;
6910 && loops_state_satisfies_p (LOOP_CLOSED_SSA
))
6911 FOR_EACH_EDGE (e
, ei
, bb
->preds
)
6912 if (e
->src
->loop_father
!= e
->dest
->loop_father
6913 && flow_loop_nested_p (e
->dest
->loop_father
,
6914 e
->src
->loop_father
))
6916 lc_phi_nodes
= true;
6920 /* When we visit a loop header substitute into loop info. */
6921 if (!iterate
&& eliminate
&& bb
->loop_father
->header
== bb
)
6923 /* Keep fields in sync with substitute_in_loop_info. */
6924 if (bb
->loop_father
->nb_iterations
)
6925 bb
->loop_father
->nb_iterations
6926 = simplify_replace_tree (bb
->loop_father
->nb_iterations
,
6927 NULL_TREE
, NULL_TREE
, &vn_valueize_wrapper
);
6930 /* Value-number all defs in the basic-block. */
6932 for (gphi_iterator gsi
= gsi_start_phis (bb
); !gsi_end_p (gsi
);
6935 gphi
*phi
= gsi
.phi ();
6936 tree res
= PHI_RESULT (phi
);
6937 vn_ssa_aux_t res_info
= VN_INFO (res
);
6940 gcc_assert (!res_info
->visited
);
6941 res_info
->valnum
= VN_TOP
;
6942 res_info
->visited
= true;
6945 /* When not iterating force backedge values to varying. */
6946 visit_stmt (phi
, !iterate_phis
);
6947 if (virtual_operand_p (res
))
6951 /* The interesting case is gcc.dg/tree-ssa/pr22230.c for correctness
6952 how we handle backedges and availability.
6953 And gcc.dg/tree-ssa/ssa-sccvn-2.c for optimization. */
6954 tree val
= res_info
->valnum
;
6955 if (res
!= val
&& !iterate
&& eliminate
)
6957 if (tree leader
= avail
.eliminate_avail (bb
, res
))
6960 /* Preserve loop-closed SSA form. */
6962 || is_gimple_min_invariant (leader
)))
6964 if (dump_file
&& (dump_flags
& TDF_DETAILS
))
6966 fprintf (dump_file
, "Replaced redundant PHI node "
6968 print_generic_expr (dump_file
, res
);
6969 fprintf (dump_file
, " with ");
6970 print_generic_expr (dump_file
, leader
);
6971 fprintf (dump_file
, "\n");
6973 avail
.eliminations
++;
6975 if (may_propagate_copy (res
, leader
))
6977 /* Schedule for removal. */
6978 avail
.to_remove
.safe_push (phi
);
6981 /* ??? Else generate a copy stmt. */
6985 /* Only make defs available that not already are. But make
6986 sure loop-closed SSA PHI node defs are picked up for
6990 || ! avail
.eliminate_avail (bb
, res
))
6991 avail
.eliminate_push_avail (bb
, res
);
6994 /* For empty BBs mark outgoing edges executable. For non-empty BBs
6995 we do this when processing the last stmt as we have to do this
6996 before elimination which otherwise forces GIMPLE_CONDs to
6997 if (1 != 0) style when seeing non-executable edges. */
6998 if (gsi_end_p (gsi_start_bb (bb
)))
7000 FOR_EACH_EDGE (e
, ei
, bb
->succs
)
7002 if (!(e
->flags
& EDGE_EXECUTABLE
))
7004 if (dump_file
&& (dump_flags
& TDF_DETAILS
))
7006 "marking outgoing edge %d -> %d executable\n",
7007 e
->src
->index
, e
->dest
->index
);
7008 e
->flags
|= EDGE_EXECUTABLE
;
7009 e
->dest
->flags
|= BB_EXECUTABLE
;
7011 else if (!(e
->dest
->flags
& BB_EXECUTABLE
))
7013 if (dump_file
&& (dump_flags
& TDF_DETAILS
))
7015 "marking destination block %d reachable\n",
7017 e
->dest
->flags
|= BB_EXECUTABLE
;
7021 for (gimple_stmt_iterator gsi
= gsi_start_bb (bb
);
7022 !gsi_end_p (gsi
); gsi_next (&gsi
))
7028 FOR_EACH_SSA_TREE_OPERAND (op
, gsi_stmt (gsi
), i
, SSA_OP_ALL_DEFS
)
7030 vn_ssa_aux_t op_info
= VN_INFO (op
);
7031 gcc_assert (!op_info
->visited
);
7032 op_info
->valnum
= VN_TOP
;
7033 op_info
->visited
= true;
7036 /* We somehow have to deal with uses that are not defined
7037 in the processed region. Forcing unvisited uses to
7038 varying here doesn't play well with def-use following during
7039 expression simplification, so we deal with this by checking
7040 the visited flag in SSA_VAL. */
7043 visit_stmt (gsi_stmt (gsi
));
7045 gimple
*last
= gsi_stmt (gsi
);
7047 switch (gimple_code (last
))
7050 e
= find_taken_edge (bb
, vn_valueize (gimple_switch_index
7051 (as_a
<gswitch
*> (last
))));
7055 tree lhs
= vn_valueize (gimple_cond_lhs (last
));
7056 tree rhs
= vn_valueize (gimple_cond_rhs (last
));
7057 tree val
= gimple_simplify (gimple_cond_code (last
),
7058 boolean_type_node
, lhs
, rhs
,
7060 /* If the condition didn't simplfy see if we have recorded
7061 an expression from sofar taken edges. */
7062 if (! val
|| TREE_CODE (val
) != INTEGER_CST
)
7064 vn_nary_op_t vnresult
;
7068 val
= vn_nary_op_lookup_pieces (2, gimple_cond_code (last
),
7069 boolean_type_node
, ops
,
7071 /* Did we get a predicated value? */
7072 if (! val
&& vnresult
&& vnresult
->predicated_values
)
7074 val
= vn_nary_op_get_predicated_value (vnresult
, bb
);
7075 if (val
&& dump_file
&& (dump_flags
& TDF_DETAILS
))
7077 fprintf (dump_file
, "Got predicated value ");
7078 print_generic_expr (dump_file
, val
, TDF_NONE
);
7079 fprintf (dump_file
, " for ");
7080 print_gimple_stmt (dump_file
, last
, TDF_SLIM
);
7085 e
= find_taken_edge (bb
, val
);
7088 /* If we didn't manage to compute the taken edge then
7089 push predicated expressions for the condition itself
7090 and related conditions to the hashtables. This allows
7091 simplification of redundant conditions which is
7092 important as early cleanup. */
7093 edge true_e
, false_e
;
7094 extract_true_false_edges_from_block (bb
, &true_e
, &false_e
);
7095 enum tree_code code
= gimple_cond_code (last
);
7096 enum tree_code icode
7097 = invert_tree_comparison (code
, HONOR_NANS (lhs
));
7102 && bitmap_bit_p (exit_bbs
, true_e
->dest
->index
))
7105 && bitmap_bit_p (exit_bbs
, false_e
->dest
->index
))
7108 vn_nary_op_insert_pieces_predicated
7109 (2, code
, boolean_type_node
, ops
,
7110 boolean_true_node
, 0, true_e
);
7112 vn_nary_op_insert_pieces_predicated
7113 (2, code
, boolean_type_node
, ops
,
7114 boolean_false_node
, 0, false_e
);
7115 if (icode
!= ERROR_MARK
)
7118 vn_nary_op_insert_pieces_predicated
7119 (2, icode
, boolean_type_node
, ops
,
7120 boolean_false_node
, 0, true_e
);
7122 vn_nary_op_insert_pieces_predicated
7123 (2, icode
, boolean_type_node
, ops
,
7124 boolean_true_node
, 0, false_e
);
7126 /* Relax for non-integers, inverted condition handled
7128 if (INTEGRAL_TYPE_P (TREE_TYPE (lhs
)))
7131 insert_related_predicates_on_edge (code
, ops
, true_e
);
7133 insert_related_predicates_on_edge (icode
, ops
, false_e
);
7139 e
= find_taken_edge (bb
, vn_valueize (gimple_goto_dest (last
)));
7146 todo
= TODO_cleanup_cfg
;
7147 if (!(e
->flags
& EDGE_EXECUTABLE
))
7149 if (dump_file
&& (dump_flags
& TDF_DETAILS
))
7151 "marking known outgoing %sedge %d -> %d executable\n",
7152 e
->flags
& EDGE_DFS_BACK
? "back-" : "",
7153 e
->src
->index
, e
->dest
->index
);
7154 e
->flags
|= EDGE_EXECUTABLE
;
7155 e
->dest
->flags
|= BB_EXECUTABLE
;
7157 else if (!(e
->dest
->flags
& BB_EXECUTABLE
))
7159 if (dump_file
&& (dump_flags
& TDF_DETAILS
))
7161 "marking destination block %d reachable\n",
7163 e
->dest
->flags
|= BB_EXECUTABLE
;
7166 else if (gsi_one_before_end_p (gsi
))
7168 FOR_EACH_EDGE (e
, ei
, bb
->succs
)
7170 if (!(e
->flags
& EDGE_EXECUTABLE
))
7172 if (dump_file
&& (dump_flags
& TDF_DETAILS
))
7174 "marking outgoing edge %d -> %d executable\n",
7175 e
->src
->index
, e
->dest
->index
);
7176 e
->flags
|= EDGE_EXECUTABLE
;
7177 e
->dest
->flags
|= BB_EXECUTABLE
;
7179 else if (!(e
->dest
->flags
& BB_EXECUTABLE
))
7181 if (dump_file
&& (dump_flags
& TDF_DETAILS
))
7183 "marking destination block %d reachable\n",
7185 e
->dest
->flags
|= BB_EXECUTABLE
;
7190 /* Eliminate. That also pushes to avail. */
7191 if (eliminate
&& ! iterate
)
7192 avail
.eliminate_stmt (bb
, &gsi
);
7194 /* If not eliminating, make all not already available defs
7196 FOR_EACH_SSA_TREE_OPERAND (op
, gsi_stmt (gsi
), i
, SSA_OP_DEF
)
7197 if (! avail
.eliminate_avail (bb
, op
))
7198 avail
.eliminate_push_avail (bb
, op
);
7201 /* Eliminate in destination PHI arguments. Always substitute in dest
7202 PHIs, even for non-executable edges. This handles region
7204 if (!iterate
&& eliminate
)
7205 FOR_EACH_EDGE (e
, ei
, bb
->succs
)
7206 for (gphi_iterator gsi
= gsi_start_phis (e
->dest
);
7207 !gsi_end_p (gsi
); gsi_next (&gsi
))
7209 gphi
*phi
= gsi
.phi ();
7210 use_operand_p use_p
= PHI_ARG_DEF_PTR_FROM_EDGE (phi
, e
);
7211 tree arg
= USE_FROM_PTR (use_p
);
7212 if (TREE_CODE (arg
) != SSA_NAME
7213 || virtual_operand_p (arg
))
7216 if (SSA_NAME_IS_DEFAULT_DEF (arg
))
7218 sprime
= SSA_VAL (arg
);
7219 gcc_assert (TREE_CODE (sprime
) != SSA_NAME
7220 || SSA_NAME_IS_DEFAULT_DEF (sprime
));
7223 /* Look for sth available at the definition block of the argument.
7224 This avoids inconsistencies between availability there which
7225 decides if the stmt can be removed and availability at the
7226 use site. The SSA property ensures that things available
7227 at the definition are also available at uses. */
7228 sprime
= avail
.eliminate_avail (gimple_bb (SSA_NAME_DEF_STMT (arg
)),
7232 && may_propagate_copy (arg
, sprime
))
7233 propagate_value (use_p
, sprime
);
7236 vn_context_bb
= NULL
;
7240 /* Unwind state per basic-block. */
7244 /* Times this block has been visited. */
7246 /* Whether to handle this as iteration point or whether to treat
7247 incoming backedge PHI values as varying. */
7249 /* Maximum RPO index this block is reachable from. */
7253 vn_reference_t ref_top
;
7255 vn_nary_op_t nary_top
;
7258 /* Unwind the RPO VN state for iteration. */
7261 do_unwind (unwind_state
*to
, int rpo_idx
, rpo_elim
&avail
, int *bb_to_rpo
)
7263 gcc_assert (to
->iterate
);
7264 for (; last_inserted_nary
!= to
->nary_top
;
7265 last_inserted_nary
= last_inserted_nary
->next
)
7268 slot
= valid_info
->nary
->find_slot_with_hash
7269 (last_inserted_nary
, last_inserted_nary
->hashcode
, NO_INSERT
);
7270 /* Predication causes the need to restore previous state. */
7271 if ((*slot
)->unwind_to
)
7272 *slot
= (*slot
)->unwind_to
;
7274 valid_info
->nary
->clear_slot (slot
);
7276 for (; last_inserted_phi
!= to
->phi_top
;
7277 last_inserted_phi
= last_inserted_phi
->next
)
7280 slot
= valid_info
->phis
->find_slot_with_hash
7281 (last_inserted_phi
, last_inserted_phi
->hashcode
, NO_INSERT
);
7282 valid_info
->phis
->clear_slot (slot
);
7284 for (; last_inserted_ref
!= to
->ref_top
;
7285 last_inserted_ref
= last_inserted_ref
->next
)
7287 vn_reference_t
*slot
;
7288 slot
= valid_info
->references
->find_slot_with_hash
7289 (last_inserted_ref
, last_inserted_ref
->hashcode
, NO_INSERT
);
7290 (*slot
)->operands
.release ();
7291 valid_info
->references
->clear_slot (slot
);
7293 obstack_free (&vn_tables_obstack
, to
->ob_top
);
7295 /* Prune [rpo_idx, ] from avail. */
7296 /* ??? This is O(number-of-values-in-region) which is
7297 O(region-size) rather than O(iteration-piece). */
7298 for (hash_table
<vn_ssa_aux_hasher
>::iterator i
= vn_ssa_aux_hash
->begin ();
7299 i
!= vn_ssa_aux_hash
->end (); ++i
)
7303 if (bb_to_rpo
[(*i
)->avail
->location
] < rpo_idx
)
7305 vn_avail
*av
= (*i
)->avail
;
7306 (*i
)->avail
= (*i
)->avail
->next
;
7307 av
->next
= avail
.m_avail_freelist
;
7308 avail
.m_avail_freelist
= av
;
7313 /* Do VN on a SEME region specified by ENTRY and EXIT_BBS in FN.
7314 If ITERATE is true then treat backedges optimistically as not
7315 executed and iterate. If ELIMINATE is true then perform
7316 elimination, otherwise leave that to the caller. */
7319 do_rpo_vn (function
*fn
, edge entry
, bitmap exit_bbs
,
7320 bool iterate
, bool eliminate
)
7324 /* We currently do not support region-based iteration when
7325 elimination is requested. */
7326 gcc_assert (!entry
|| !iterate
|| !eliminate
);
7327 /* When iterating we need loop info up-to-date. */
7328 gcc_assert (!iterate
|| !loops_state_satisfies_p (LOOPS_NEED_FIXUP
));
7330 bool do_region
= entry
!= NULL
;
7333 entry
= single_succ_edge (ENTRY_BLOCK_PTR_FOR_FN (fn
));
7334 exit_bbs
= BITMAP_ALLOC (NULL
);
7335 bitmap_set_bit (exit_bbs
, EXIT_BLOCK
);
7338 /* Clear EDGE_DFS_BACK on "all" entry edges, RPO order compute will
7339 re-mark those that are contained in the region. */
7342 FOR_EACH_EDGE (e
, ei
, entry
->dest
->preds
)
7343 e
->flags
&= ~EDGE_DFS_BACK
;
7345 int *rpo
= XNEWVEC (int, n_basic_blocks_for_fn (fn
) - NUM_FIXED_BLOCKS
);
7346 auto_vec
<std::pair
<int, int> > toplevel_scc_extents
;
7347 int n
= rev_post_order_and_mark_dfs_back_seme
7348 (fn
, entry
, exit_bbs
, true, rpo
, !iterate
? &toplevel_scc_extents
: NULL
);
7351 BITMAP_FREE (exit_bbs
);
7353 /* If there are any non-DFS_BACK edges into entry->dest skip
7354 processing PHI nodes for that block. This supports
7355 value-numbering loop bodies w/o the actual loop. */
7356 FOR_EACH_EDGE (e
, ei
, entry
->dest
->preds
)
7358 && !(e
->flags
& EDGE_DFS_BACK
))
7360 bool skip_entry_phis
= e
!= NULL
;
7361 if (skip_entry_phis
&& dump_file
&& (dump_flags
& TDF_DETAILS
))
7362 fprintf (dump_file
, "Region does not contain all edges into "
7363 "the entry block, skipping its PHIs.\n");
7365 int *bb_to_rpo
= XNEWVEC (int, last_basic_block_for_fn (fn
));
7366 for (int i
= 0; i
< n
; ++i
)
7367 bb_to_rpo
[rpo
[i
]] = i
;
7369 unwind_state
*rpo_state
= XNEWVEC (unwind_state
, n
);
7371 rpo_elim
avail (entry
->dest
);
7374 /* Verify we have no extra entries into the region. */
7375 if (flag_checking
&& do_region
)
7377 auto_bb_flag
bb_in_region (fn
);
7378 for (int i
= 0; i
< n
; ++i
)
7380 basic_block bb
= BASIC_BLOCK_FOR_FN (fn
, rpo
[i
]);
7381 bb
->flags
|= bb_in_region
;
7383 /* We can't merge the first two loops because we cannot rely
7384 on EDGE_DFS_BACK for edges not within the region. But if
7385 we decide to always have the bb_in_region flag we can
7386 do the checking during the RPO walk itself (but then it's
7387 also easy to handle MEME conservatively). */
7388 for (int i
= 0; i
< n
; ++i
)
7390 basic_block bb
= BASIC_BLOCK_FOR_FN (fn
, rpo
[i
]);
7393 FOR_EACH_EDGE (e
, ei
, bb
->preds
)
7394 gcc_assert (e
== entry
7395 || (skip_entry_phis
&& bb
== entry
->dest
)
7396 || (e
->src
->flags
& bb_in_region
));
7398 for (int i
= 0; i
< n
; ++i
)
7400 basic_block bb
= BASIC_BLOCK_FOR_FN (fn
, rpo
[i
]);
7401 bb
->flags
&= ~bb_in_region
;
7405 /* Create the VN state. For the initial size of the various hashtables
7406 use a heuristic based on region size and number of SSA names. */
7407 unsigned region_size
= (((unsigned HOST_WIDE_INT
)n
* num_ssa_names
)
7408 / (n_basic_blocks_for_fn (fn
) - NUM_FIXED_BLOCKS
));
7409 VN_TOP
= create_tmp_var_raw (void_type_node
, "vn_top");
7412 vn_ssa_aux_hash
= new hash_table
<vn_ssa_aux_hasher
> (region_size
* 2);
7413 gcc_obstack_init (&vn_ssa_aux_obstack
);
7415 gcc_obstack_init (&vn_tables_obstack
);
7416 gcc_obstack_init (&vn_tables_insert_obstack
);
7417 valid_info
= XCNEW (struct vn_tables_s
);
7418 allocate_vn_table (valid_info
, region_size
);
7419 last_inserted_ref
= NULL
;
7420 last_inserted_phi
= NULL
;
7421 last_inserted_nary
= NULL
;
7423 vn_valueize
= rpo_vn_valueize
;
7425 /* Initialize the unwind state and edge/BB executable state. */
7426 unsigned curr_scc
= 0;
7427 for (int i
= 0; i
< n
; ++i
)
7429 basic_block bb
= BASIC_BLOCK_FOR_FN (fn
, rpo
[i
]);
7430 rpo_state
[i
].visited
= 0;
7431 rpo_state
[i
].max_rpo
= i
;
7432 if (!iterate
&& curr_scc
< toplevel_scc_extents
.length ())
7434 if (i
>= toplevel_scc_extents
[curr_scc
].first
7435 && i
<= toplevel_scc_extents
[curr_scc
].second
)
7436 rpo_state
[i
].max_rpo
= toplevel_scc_extents
[curr_scc
].second
;
7437 if (i
== toplevel_scc_extents
[curr_scc
].second
)
7440 bb
->flags
&= ~BB_EXECUTABLE
;
7441 bool has_backedges
= false;
7444 FOR_EACH_EDGE (e
, ei
, bb
->preds
)
7446 if (e
->flags
& EDGE_DFS_BACK
)
7447 has_backedges
= true;
7448 e
->flags
&= ~EDGE_EXECUTABLE
;
7449 if (iterate
|| e
== entry
|| (skip_entry_phis
&& bb
== entry
->dest
))
7452 rpo_state
[i
].iterate
= iterate
&& has_backedges
;
7454 entry
->flags
|= EDGE_EXECUTABLE
;
7455 entry
->dest
->flags
|= BB_EXECUTABLE
;
7457 /* As heuristic to improve compile-time we handle only the N innermost
7458 loops and the outermost one optimistically. */
7462 unsigned max_depth
= param_rpo_vn_max_loop_depth
;
7463 FOR_EACH_LOOP (loop
, LI_ONLY_INNERMOST
)
7464 if (loop_depth (loop
) > max_depth
)
7465 for (unsigned i
= 2;
7466 i
< loop_depth (loop
) - max_depth
; ++i
)
7468 basic_block header
= superloop_at_depth (loop
, i
)->header
;
7469 bool non_latch_backedge
= false;
7472 FOR_EACH_EDGE (e
, ei
, header
->preds
)
7473 if (e
->flags
& EDGE_DFS_BACK
)
7475 /* There can be a non-latch backedge into the header
7476 which is part of an outer irreducible region. We
7477 cannot avoid iterating this block then. */
7478 if (!dominated_by_p (CDI_DOMINATORS
,
7481 if (dump_file
&& (dump_flags
& TDF_DETAILS
))
7482 fprintf (dump_file
, "non-latch backedge %d -> %d "
7483 "forces iteration of loop %d\n",
7484 e
->src
->index
, e
->dest
->index
, loop
->num
);
7485 non_latch_backedge
= true;
7488 e
->flags
|= EDGE_EXECUTABLE
;
7490 rpo_state
[bb_to_rpo
[header
->index
]].iterate
= non_latch_backedge
;
7497 /* Go and process all blocks, iterating as necessary. */
7500 basic_block bb
= BASIC_BLOCK_FOR_FN (fn
, rpo
[idx
]);
7502 /* If the block has incoming backedges remember unwind state. This
7503 is required even for non-executable blocks since in irreducible
7504 regions we might reach them via the backedge and re-start iterating
7506 Note we can individually mark blocks with incoming backedges to
7507 not iterate where we then handle PHIs conservatively. We do that
7508 heuristically to reduce compile-time for degenerate cases. */
7509 if (rpo_state
[idx
].iterate
)
7511 rpo_state
[idx
].ob_top
= obstack_alloc (&vn_tables_obstack
, 0);
7512 rpo_state
[idx
].ref_top
= last_inserted_ref
;
7513 rpo_state
[idx
].phi_top
= last_inserted_phi
;
7514 rpo_state
[idx
].nary_top
= last_inserted_nary
;
7517 if (!(bb
->flags
& BB_EXECUTABLE
))
7519 if (dump_file
&& (dump_flags
& TDF_DETAILS
))
7520 fprintf (dump_file
, "Block %d: BB%d found not executable\n",
7526 if (dump_file
&& (dump_flags
& TDF_DETAILS
))
7527 fprintf (dump_file
, "Processing block %d: BB%d\n", idx
, bb
->index
);
7529 todo
|= process_bb (avail
, bb
,
7530 rpo_state
[idx
].visited
!= 0,
7531 rpo_state
[idx
].iterate
,
7532 iterate
, eliminate
, do_region
, exit_bbs
, false);
7533 rpo_state
[idx
].visited
++;
7535 /* Verify if changed values flow over executable outgoing backedges
7536 and those change destination PHI values (that's the thing we
7537 can easily verify). Reduce over all such edges to the farthest
7539 int iterate_to
= -1;
7542 FOR_EACH_EDGE (e
, ei
, bb
->succs
)
7543 if ((e
->flags
& (EDGE_DFS_BACK
|EDGE_EXECUTABLE
))
7544 == (EDGE_DFS_BACK
|EDGE_EXECUTABLE
)
7545 && rpo_state
[bb_to_rpo
[e
->dest
->index
]].iterate
)
7547 int destidx
= bb_to_rpo
[e
->dest
->index
];
7548 if (!rpo_state
[destidx
].visited
)
7550 if (dump_file
&& (dump_flags
& TDF_DETAILS
))
7551 fprintf (dump_file
, "Unvisited destination %d\n",
7553 if (iterate_to
== -1 || destidx
< iterate_to
)
7554 iterate_to
= destidx
;
7557 if (dump_file
&& (dump_flags
& TDF_DETAILS
))
7558 fprintf (dump_file
, "Looking for changed values of backedge"
7559 " %d->%d destination PHIs\n",
7560 e
->src
->index
, e
->dest
->index
);
7561 vn_context_bb
= e
->dest
;
7563 for (gsi
= gsi_start_phis (e
->dest
);
7564 !gsi_end_p (gsi
); gsi_next (&gsi
))
7566 bool inserted
= false;
7567 /* While we'd ideally just iterate on value changes
7568 we CSE PHIs and do that even across basic-block
7569 boundaries. So even hashtable state changes can
7570 be important (which is roughly equivalent to
7571 PHI argument value changes). To not excessively
7572 iterate because of that we track whether a PHI
7573 was CSEd to with GF_PLF_1. */
7574 bool phival_changed
;
7575 if ((phival_changed
= visit_phi (gsi
.phi (),
7577 || (inserted
&& gimple_plf (gsi
.phi (), GF_PLF_1
)))
7580 && dump_file
&& (dump_flags
& TDF_DETAILS
))
7581 fprintf (dump_file
, "PHI was CSEd and hashtable "
7582 "state (changed)\n");
7583 if (iterate_to
== -1 || destidx
< iterate_to
)
7584 iterate_to
= destidx
;
7588 vn_context_bb
= NULL
;
7590 if (iterate_to
!= -1)
7592 do_unwind (&rpo_state
[iterate_to
], iterate_to
, avail
, bb_to_rpo
);
7594 if (dump_file
&& (dump_flags
& TDF_DETAILS
))
7595 fprintf (dump_file
, "Iterating to %d BB%d\n",
7596 iterate_to
, rpo
[iterate_to
]);
7606 /* Process all blocks greedily with a worklist that enforces RPO
7607 processing of reachable blocks. */
7608 auto_bitmap worklist
;
7609 bitmap_set_bit (worklist
, 0);
7610 while (!bitmap_empty_p (worklist
))
7612 int idx
= bitmap_first_set_bit (worklist
);
7613 bitmap_clear_bit (worklist
, idx
);
7614 basic_block bb
= BASIC_BLOCK_FOR_FN (fn
, rpo
[idx
]);
7615 gcc_assert ((bb
->flags
& BB_EXECUTABLE
)
7616 && !rpo_state
[idx
].visited
);
7618 if (dump_file
&& (dump_flags
& TDF_DETAILS
))
7619 fprintf (dump_file
, "Processing block %d: BB%d\n", idx
, bb
->index
);
7621 /* When we run into predecessor edges where we cannot trust its
7622 executable state mark them executable so PHI processing will
7624 ??? Do we need to force arguments flowing over that edge
7625 to be varying or will they even always be? */
7628 FOR_EACH_EDGE (e
, ei
, bb
->preds
)
7629 if (!(e
->flags
& EDGE_EXECUTABLE
)
7630 && (bb
== entry
->dest
7631 || (!rpo_state
[bb_to_rpo
[e
->src
->index
]].visited
7632 && (rpo_state
[bb_to_rpo
[e
->src
->index
]].max_rpo
7635 if (dump_file
&& (dump_flags
& TDF_DETAILS
))
7636 fprintf (dump_file
, "Cannot trust state of predecessor "
7637 "edge %d -> %d, marking executable\n",
7638 e
->src
->index
, e
->dest
->index
);
7639 e
->flags
|= EDGE_EXECUTABLE
;
7643 todo
|= process_bb (avail
, bb
, false, false, false, eliminate
,
7644 do_region
, exit_bbs
,
7645 skip_entry_phis
&& bb
== entry
->dest
);
7646 rpo_state
[idx
].visited
++;
7648 FOR_EACH_EDGE (e
, ei
, bb
->succs
)
7649 if ((e
->flags
& EDGE_EXECUTABLE
)
7650 && e
->dest
->index
!= EXIT_BLOCK
7651 && (!do_region
|| !bitmap_bit_p (exit_bbs
, e
->dest
->index
))
7652 && !rpo_state
[bb_to_rpo
[e
->dest
->index
]].visited
)
7653 bitmap_set_bit (worklist
, bb_to_rpo
[e
->dest
->index
]);
7657 /* If statistics or dump file active. */
7659 unsigned max_visited
= 1;
7660 for (int i
= 0; i
< n
; ++i
)
7662 basic_block bb
= BASIC_BLOCK_FOR_FN (fn
, rpo
[i
]);
7663 if (bb
->flags
& BB_EXECUTABLE
)
7665 statistics_histogram_event (cfun
, "RPO block visited times",
7666 rpo_state
[i
].visited
);
7667 if (rpo_state
[i
].visited
> max_visited
)
7668 max_visited
= rpo_state
[i
].visited
;
7670 unsigned nvalues
= 0, navail
= 0;
7671 for (hash_table
<vn_ssa_aux_hasher
>::iterator i
= vn_ssa_aux_hash
->begin ();
7672 i
!= vn_ssa_aux_hash
->end (); ++i
)
7675 vn_avail
*av
= (*i
)->avail
;
7682 statistics_counter_event (cfun
, "RPO blocks", n
);
7683 statistics_counter_event (cfun
, "RPO blocks visited", nblk
);
7684 statistics_counter_event (cfun
, "RPO blocks executable", nex
);
7685 statistics_histogram_event (cfun
, "RPO iterations", 10*nblk
/ nex
);
7686 statistics_histogram_event (cfun
, "RPO num values", nvalues
);
7687 statistics_histogram_event (cfun
, "RPO num avail", navail
);
7688 statistics_histogram_event (cfun
, "RPO num lattice",
7689 vn_ssa_aux_hash
->elements ());
7690 if (dump_file
&& (dump_flags
& (TDF_DETAILS
|TDF_STATS
)))
7692 fprintf (dump_file
, "RPO iteration over %d blocks visited %" PRIu64
7693 " blocks in total discovering %d executable blocks iterating "
7694 "%d.%d times, a block was visited max. %u times\n",
7696 (int)((10*nblk
/ nex
)/10), (int)((10*nblk
/ nex
)%10),
7698 fprintf (dump_file
, "RPO tracked %d values available at %d locations "
7699 "and %" PRIu64
" lattice elements\n",
7700 nvalues
, navail
, (uint64_t) vn_ssa_aux_hash
->elements ());
7705 /* When !iterate we already performed elimination during the RPO
7709 /* Elimination for region-based VN needs to be done within the
7711 gcc_assert (! do_region
);
7712 /* Note we can't use avail.walk here because that gets confused
7713 by the existing availability and it will be less efficient
7715 todo
|= eliminate_with_rpo_vn (NULL
);
7718 todo
|= avail
.eliminate_cleanup (do_region
);
7724 XDELETEVEC (bb_to_rpo
);
7726 XDELETEVEC (rpo_state
);
7731 /* Region-based entry for RPO VN. Performs value-numbering and elimination
7732 on the SEME region specified by ENTRY and EXIT_BBS. If ENTRY is not
7733 the only edge into the region at ENTRY->dest PHI nodes in ENTRY->dest
7734 are not considered. */
7737 do_rpo_vn (function
*fn
, edge entry
, bitmap exit_bbs
)
7739 default_vn_walk_kind
= VN_WALKREWRITE
;
7740 unsigned todo
= do_rpo_vn (fn
, entry
, exit_bbs
, false, true);
7748 const pass_data pass_data_fre
=
7750 GIMPLE_PASS
, /* type */
7752 OPTGROUP_NONE
, /* optinfo_flags */
7753 TV_TREE_FRE
, /* tv_id */
7754 ( PROP_cfg
| PROP_ssa
), /* properties_required */
7755 0, /* properties_provided */
7756 0, /* properties_destroyed */
7757 0, /* todo_flags_start */
7758 0, /* todo_flags_finish */
7761 class pass_fre
: public gimple_opt_pass
7764 pass_fre (gcc::context
*ctxt
)
7765 : gimple_opt_pass (pass_data_fre
, ctxt
), may_iterate (true)
7768 /* opt_pass methods: */
7769 opt_pass
* clone () { return new pass_fre (m_ctxt
); }
7770 void set_pass_param (unsigned int n
, bool param
)
7772 gcc_assert (n
== 0);
7773 may_iterate
= param
;
7775 virtual bool gate (function
*)
7777 return flag_tree_fre
!= 0 && (may_iterate
|| optimize
> 1);
7779 virtual unsigned int execute (function
*);
7783 }; // class pass_fre
7786 pass_fre::execute (function
*fun
)
7790 /* At -O[1g] use the cheap non-iterating mode. */
7791 bool iterate_p
= may_iterate
&& (optimize
> 1);
7792 calculate_dominance_info (CDI_DOMINATORS
);
7794 loop_optimizer_init (AVOID_CFG_MODIFICATIONS
);
7796 default_vn_walk_kind
= VN_WALKREWRITE
;
7797 todo
= do_rpo_vn (fun
, NULL
, NULL
, iterate_p
, true);
7801 loop_optimizer_finalize ();
7803 /* For late FRE after IVOPTs and unrolling, see if we can
7804 remove some TREE_ADDRESSABLE and rewrite stuff into SSA. */
7806 todo
|= TODO_update_address_taken
;
7814 make_pass_fre (gcc::context
*ctxt
)
7816 return new pass_fre (ctxt
);
7819 #undef BB_EXECUTABLE