1 /* Scalar Replacement of Aggregates (SRA) converts some structure
2 references into scalar references, exposing them to the scalar
4 Copyright (C) 2008, 2009, 2010 Free Software Foundation, Inc.
5 Contributed by Martin Jambor <mjambor@suse.cz>
7 This file is part of GCC.
9 GCC is free software; you can redistribute it and/or modify it under
10 the terms of the GNU General Public License as published by the Free
11 Software Foundation; either version 3, or (at your option) any later
14 GCC is distributed in the hope that it will be useful, but WITHOUT ANY
15 WARRANTY; without even the implied warranty of MERCHANTABILITY or
16 FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
19 You should have received a copy of the GNU General Public License
20 along with GCC; see the file COPYING3. If not see
21 <http://www.gnu.org/licenses/>. */
23 /* This file implements Scalar Reduction of Aggregates (SRA). SRA is run
24 twice, once in the early stages of compilation (early SRA) and once in the
25 late stages (late SRA). The aim of both is to turn references to scalar
26 parts of aggregates into uses of independent scalar variables.
28 The two passes are nearly identical, the only difference is that early SRA
29 does not scalarize unions which are used as the result in a GIMPLE_RETURN
30 statement because together with inlining this can lead to weird type
33 Both passes operate in four stages:
35 1. The declarations that have properties which make them candidates for
36 scalarization are identified in function find_var_candidates(). The
37 candidates are stored in candidate_bitmap.
39 2. The function body is scanned. In the process, declarations which are
40 used in a manner that prevent their scalarization are removed from the
41 candidate bitmap. More importantly, for every access into an aggregate,
42 an access structure (struct access) is created by create_access() and
43 stored in a vector associated with the aggregate. Among other
44 information, the aggregate declaration, the offset and size of the access
45 and its type are stored in the structure.
47 On a related note, assign_link structures are created for every assign
48 statement between candidate aggregates and attached to the related
51 3. The vectors of accesses are analyzed. They are first sorted according to
52 their offset and size and then scanned for partially overlapping accesses
53 (i.e. those which overlap but one is not entirely within another). Such
54 an access disqualifies the whole aggregate from being scalarized.
56 If there is no such inhibiting overlap, a representative access structure
57 is chosen for every unique combination of offset and size. Afterwards,
58 the pass builds a set of trees from these structures, in which children
59 of an access are within their parent (in terms of offset and size).
61 Then accesses are propagated whenever possible (i.e. in cases when it
62 does not create a partially overlapping access) across assign_links from
63 the right hand side to the left hand side.
65 Then the set of trees for each declaration is traversed again and those
66 accesses which should be replaced by a scalar are identified.
68 4. The function is traversed again, and for every reference into an
69 aggregate that has some component which is about to be scalarized,
70 statements are amended and new statements are created as necessary.
71 Finally, if a parameter got scalarized, the scalar replacements are
72 initialized with values from respective parameter aggregates. */
76 #include "coretypes.h"
77 #include "alloc-pool.h"
83 #include "tree-flow.h"
85 #include "diagnostic.h"
86 #include "statistics.h"
87 #include "tree-dump.h"
93 /* Enumeration of all aggregate reductions we can do. */
94 enum sra_mode { SRA_MODE_EARLY_IPA, /* early call regularization */
95 SRA_MODE_EARLY_INTRA, /* early intraprocedural SRA */
96 SRA_MODE_INTRA }; /* late intraprocedural SRA */
98 /* Global variable describing which aggregate reduction we are performing at
100 static enum sra_mode sra_mode;
104 /* ACCESS represents each access to an aggregate variable (as a whole or a
105 part). It can also represent a group of accesses that refer to exactly the
106 same fragment of an aggregate (i.e. those that have exactly the same offset
107 and size). Such representatives for a single aggregate, once determined,
108 are linked in a linked list and have the group fields set.
110 Moreover, when doing intraprocedural SRA, a tree is built from those
111 representatives (by the means of first_child and next_sibling pointers), in
112 which all items in a subtree are "within" the root, i.e. their offset is
113 greater or equal to offset of the root and offset+size is smaller or equal
114 to offset+size of the root. Children of an access are sorted by offset.
116 Note that accesses to parts of vector and complex number types always
117 represented by an access to the whole complex number or a vector. It is a
118 duty of the modifying functions to replace them appropriately. */
122 /* Values returned by `get_ref_base_and_extent' for each component reference
123 If EXPR isn't a component reference just set `BASE = EXPR', `OFFSET = 0',
124 `SIZE = TREE_SIZE (TREE_TYPE (expr))'. */
125 HOST_WIDE_INT offset;
129 /* Expression. It is context dependent so do not use it to create new
130 expressions to access the original aggregate. See PR 42154 for a
136 /* The statement this access belongs to. */
139 /* Next group representative for this aggregate. */
140 struct access *next_grp;
142 /* Pointer to the group representative. Pointer to itself if the struct is
143 the representative. */
144 struct access *group_representative;
146 /* If this access has any children (in terms of the definition above), this
147 points to the first one. */
148 struct access *first_child;
150 /* In intraprocedural SRA, pointer to the next sibling in the access tree as
151 described above. In IPA-SRA this is a pointer to the next access
152 belonging to the same group (having the same representative). */
153 struct access *next_sibling;
155 /* Pointers to the first and last element in the linked list of assign
157 struct assign_link *first_link, *last_link;
159 /* Pointer to the next access in the work queue. */
160 struct access *next_queued;
162 /* Replacement variable for this access "region." Never to be accessed
163 directly, always only by the means of get_access_replacement() and only
164 when grp_to_be_replaced flag is set. */
165 tree replacement_decl;
167 /* Is this particular access write access? */
170 /* Is this access an artificial one created to scalarize some record
172 unsigned total_scalarization : 1;
174 /* Is this access currently in the work queue? */
175 unsigned grp_queued : 1;
177 /* Does this group contain a write access? This flag is propagated down the
179 unsigned grp_write : 1;
181 /* Does this group contain a read access? This flag is propagated down the
183 unsigned grp_read : 1;
185 /* Does this group contain a read access that comes from an assignment
186 statement? This flag is propagated down the access tree. */
187 unsigned grp_assignment_read : 1;
189 /* Other passes of the analysis use this bit to make function
190 analyze_access_subtree create scalar replacements for this group if
192 unsigned grp_hint : 1;
194 /* Is the subtree rooted in this access fully covered by scalar
196 unsigned grp_covered : 1;
198 /* If set to true, this access and all below it in an access tree must not be
200 unsigned grp_unscalarizable_region : 1;
202 /* Whether data have been written to parts of the aggregate covered by this
203 access which is not to be scalarized. This flag is propagated up in the
205 unsigned grp_unscalarized_data : 1;
207 /* Does this access and/or group contain a write access through a
209 unsigned grp_partial_lhs : 1;
211 /* Set when a scalar replacement should be created for this variable. We do
212 the decision and creation at different places because create_tmp_var
213 cannot be called from within FOR_EACH_REFERENCED_VAR. */
214 unsigned grp_to_be_replaced : 1;
216 /* Is it possible that the group refers to data which might be (directly or
217 otherwise) modified? */
218 unsigned grp_maybe_modified : 1;
220 /* Set when this is a representative of a pointer to scalar (i.e. by
221 reference) parameter which we consider for turning into a plain scalar
222 (i.e. a by value parameter). */
223 unsigned grp_scalar_ptr : 1;
225 /* Set when we discover that this pointer is not safe to dereference in the
227 unsigned grp_not_necessarilly_dereferenced : 1;
230 typedef struct access *access_p;
232 DEF_VEC_P (access_p);
233 DEF_VEC_ALLOC_P (access_p, heap);
235 /* Alloc pool for allocating access structures. */
236 static alloc_pool access_pool;
238 /* A structure linking lhs and rhs accesses from an aggregate assignment. They
239 are used to propagate subaccesses from rhs to lhs as long as they don't
240 conflict with what is already there. */
243 struct access *lacc, *racc;
244 struct assign_link *next;
247 /* Alloc pool for allocating assign link structures. */
248 static alloc_pool link_pool;
250 /* Base (tree) -> Vector (VEC(access_p,heap) *) map. */
251 static struct pointer_map_t *base_access_vec;
253 /* Bitmap of candidates. */
254 static bitmap candidate_bitmap;
256 /* Bitmap of candidates which we should try to entirely scalarize away and
257 those which cannot be (because they are and need be used as a whole). */
258 static bitmap should_scalarize_away_bitmap, cannot_scalarize_away_bitmap;
260 /* Obstack for creation of fancy names. */
261 static struct obstack name_obstack;
263 /* Head of a linked list of accesses that need to have its subaccesses
264 propagated to their assignment counterparts. */
265 static struct access *work_queue_head;
267 /* Number of parameters of the analyzed function when doing early ipa SRA. */
268 static int func_param_count;
270 /* scan_function sets the following to true if it encounters a call to
271 __builtin_apply_args. */
272 static bool encountered_apply_args;
274 /* Set by scan_function when it finds a recursive call. */
275 static bool encountered_recursive_call;
277 /* Set by scan_function when it finds a recursive call with less actual
278 arguments than formal parameters.. */
279 static bool encountered_unchangable_recursive_call;
281 /* This is a table in which for each basic block and parameter there is a
282 distance (offset + size) in that parameter which is dereferenced and
283 accessed in that BB. */
284 static HOST_WIDE_INT *bb_dereferences;
285 /* Bitmap of BBs that can cause the function to "stop" progressing by
286 returning, throwing externally, looping infinitely or calling a function
287 which might abort etc.. */
288 static bitmap final_bbs;
290 /* Representative of no accesses at all. */
291 static struct access no_accesses_representant;
293 /* Predicate to test the special value. */
296 no_accesses_p (struct access *access)
298 return access == &no_accesses_representant;
301 /* Dump contents of ACCESS to file F in a human friendly way. If GRP is true,
302 representative fields are dumped, otherwise those which only describe the
303 individual access are. */
307 /* Number of processed aggregates is readily available in
308 analyze_all_variable_accesses and so is not stored here. */
310 /* Number of created scalar replacements. */
313 /* Number of times sra_modify_expr or sra_modify_assign themselves changed an
317 /* Number of statements created by generate_subtree_copies. */
320 /* Number of statements created by load_assign_lhs_subreplacements. */
323 /* Number of times sra_modify_assign has deleted a statement. */
326 /* Number of times sra_modify_assign has to deal with subaccesses of LHS and
327 RHS reparately due to type conversions or nonexistent matching
329 int separate_lhs_rhs_handling;
331 /* Number of parameters that were removed because they were unused. */
332 int deleted_unused_parameters;
334 /* Number of scalars passed as parameters by reference that have been
335 converted to be passed by value. */
336 int scalar_by_ref_to_by_val;
338 /* Number of aggregate parameters that were replaced by one or more of their
340 int aggregate_params_reduced;
342 /* Numbber of components created when splitting aggregate parameters. */
343 int param_reductions_created;
347 dump_access (FILE *f, struct access *access, bool grp)
349 fprintf (f, "access { ");
350 fprintf (f, "base = (%d)'", DECL_UID (access->base));
351 print_generic_expr (f, access->base, 0);
352 fprintf (f, "', offset = " HOST_WIDE_INT_PRINT_DEC, access->offset);
353 fprintf (f, ", size = " HOST_WIDE_INT_PRINT_DEC, access->size);
354 fprintf (f, ", expr = ");
355 print_generic_expr (f, access->expr, 0);
356 fprintf (f, ", type = ");
357 print_generic_expr (f, access->type, 0);
359 fprintf (f, ", grp_write = %d, total_scalarization = %d, "
360 "grp_read = %d, grp_hint = %d, "
361 "grp_covered = %d, grp_unscalarizable_region = %d, "
362 "grp_unscalarized_data = %d, grp_partial_lhs = %d, "
363 "grp_to_be_replaced = %d, grp_maybe_modified = %d, "
364 "grp_not_necessarilly_dereferenced = %d\n",
365 access->grp_write, access->total_scalarization,
366 access->grp_read, access->grp_hint,
367 access->grp_covered, access->grp_unscalarizable_region,
368 access->grp_unscalarized_data, access->grp_partial_lhs,
369 access->grp_to_be_replaced, access->grp_maybe_modified,
370 access->grp_not_necessarilly_dereferenced);
372 fprintf (f, ", write = %d, total_scalarization = %d, "
373 "grp_partial_lhs = %d\n",
374 access->write, access->total_scalarization,
375 access->grp_partial_lhs);
378 /* Dump a subtree rooted in ACCESS to file F, indent by LEVEL. */
381 dump_access_tree_1 (FILE *f, struct access *access, int level)
387 for (i = 0; i < level; i++)
388 fputs ("* ", dump_file);
390 dump_access (f, access, true);
392 if (access->first_child)
393 dump_access_tree_1 (f, access->first_child, level + 1);
395 access = access->next_sibling;
400 /* Dump all access trees for a variable, given the pointer to the first root in
404 dump_access_tree (FILE *f, struct access *access)
406 for (; access; access = access->next_grp)
407 dump_access_tree_1 (f, access, 0);
410 /* Return true iff ACC is non-NULL and has subaccesses. */
413 access_has_children_p (struct access *acc)
415 return acc && acc->first_child;
418 /* Return a vector of pointers to accesses for the variable given in BASE or
419 NULL if there is none. */
421 static VEC (access_p, heap) *
422 get_base_access_vector (tree base)
426 slot = pointer_map_contains (base_access_vec, base);
430 return *(VEC (access_p, heap) **) slot;
433 /* Find an access with required OFFSET and SIZE in a subtree of accesses rooted
434 in ACCESS. Return NULL if it cannot be found. */
436 static struct access *
437 find_access_in_subtree (struct access *access, HOST_WIDE_INT offset,
440 while (access && (access->offset != offset || access->size != size))
442 struct access *child = access->first_child;
444 while (child && (child->offset + child->size <= offset))
445 child = child->next_sibling;
452 /* Return the first group representative for DECL or NULL if none exists. */
454 static struct access *
455 get_first_repr_for_decl (tree base)
457 VEC (access_p, heap) *access_vec;
459 access_vec = get_base_access_vector (base);
463 return VEC_index (access_p, access_vec, 0);
466 /* Find an access representative for the variable BASE and given OFFSET and
467 SIZE. Requires that access trees have already been built. Return NULL if
468 it cannot be found. */
470 static struct access *
471 get_var_base_offset_size_access (tree base, HOST_WIDE_INT offset,
474 struct access *access;
476 access = get_first_repr_for_decl (base);
477 while (access && (access->offset + access->size <= offset))
478 access = access->next_grp;
482 return find_access_in_subtree (access, offset, size);
485 /* Add LINK to the linked list of assign links of RACC. */
487 add_link_to_rhs (struct access *racc, struct assign_link *link)
489 gcc_assert (link->racc == racc);
491 if (!racc->first_link)
493 gcc_assert (!racc->last_link);
494 racc->first_link = link;
497 racc->last_link->next = link;
499 racc->last_link = link;
503 /* Move all link structures in their linked list in OLD_RACC to the linked list
506 relink_to_new_repr (struct access *new_racc, struct access *old_racc)
508 if (!old_racc->first_link)
510 gcc_assert (!old_racc->last_link);
514 if (new_racc->first_link)
516 gcc_assert (!new_racc->last_link->next);
517 gcc_assert (!old_racc->last_link || !old_racc->last_link->next);
519 new_racc->last_link->next = old_racc->first_link;
520 new_racc->last_link = old_racc->last_link;
524 gcc_assert (!new_racc->last_link);
526 new_racc->first_link = old_racc->first_link;
527 new_racc->last_link = old_racc->last_link;
529 old_racc->first_link = old_racc->last_link = NULL;
532 /* Add ACCESS to the work queue (which is actually a stack). */
535 add_access_to_work_queue (struct access *access)
537 if (!access->grp_queued)
539 gcc_assert (!access->next_queued);
540 access->next_queued = work_queue_head;
541 access->grp_queued = 1;
542 work_queue_head = access;
546 /* Pop an access from the work queue, and return it, assuming there is one. */
548 static struct access *
549 pop_access_from_work_queue (void)
551 struct access *access = work_queue_head;
553 work_queue_head = access->next_queued;
554 access->next_queued = NULL;
555 access->grp_queued = 0;
560 /* Allocate necessary structures. */
563 sra_initialize (void)
565 candidate_bitmap = BITMAP_ALLOC (NULL);
566 should_scalarize_away_bitmap = BITMAP_ALLOC (NULL);
567 cannot_scalarize_away_bitmap = BITMAP_ALLOC (NULL);
568 gcc_obstack_init (&name_obstack);
569 access_pool = create_alloc_pool ("SRA accesses", sizeof (struct access), 16);
570 link_pool = create_alloc_pool ("SRA links", sizeof (struct assign_link), 16);
571 base_access_vec = pointer_map_create ();
572 memset (&sra_stats, 0, sizeof (sra_stats));
573 encountered_apply_args = false;
574 encountered_recursive_call = false;
575 encountered_unchangable_recursive_call = false;
578 /* Hook fed to pointer_map_traverse, deallocate stored vectors. */
581 delete_base_accesses (const void *key ATTRIBUTE_UNUSED, void **value,
582 void *data ATTRIBUTE_UNUSED)
584 VEC (access_p, heap) *access_vec;
585 access_vec = (VEC (access_p, heap) *) *value;
586 VEC_free (access_p, heap, access_vec);
591 /* Deallocate all general structures. */
594 sra_deinitialize (void)
596 BITMAP_FREE (candidate_bitmap);
597 BITMAP_FREE (should_scalarize_away_bitmap);
598 BITMAP_FREE (cannot_scalarize_away_bitmap);
599 free_alloc_pool (access_pool);
600 free_alloc_pool (link_pool);
601 obstack_free (&name_obstack, NULL);
603 pointer_map_traverse (base_access_vec, delete_base_accesses, NULL);
604 pointer_map_destroy (base_access_vec);
607 /* Remove DECL from candidates for SRA and write REASON to the dump file if
610 disqualify_candidate (tree decl, const char *reason)
612 bitmap_clear_bit (candidate_bitmap, DECL_UID (decl));
614 if (dump_file && (dump_flags & TDF_DETAILS))
616 fprintf (dump_file, "! Disqualifying ");
617 print_generic_expr (dump_file, decl, 0);
618 fprintf (dump_file, " - %s\n", reason);
622 /* Return true iff the type contains a field or an element which does not allow
626 type_internals_preclude_sra_p (tree type)
631 switch (TREE_CODE (type))
635 case QUAL_UNION_TYPE:
636 for (fld = TYPE_FIELDS (type); fld; fld = TREE_CHAIN (fld))
637 if (TREE_CODE (fld) == FIELD_DECL)
639 tree ft = TREE_TYPE (fld);
641 if (TREE_THIS_VOLATILE (fld)
642 || !DECL_FIELD_OFFSET (fld) || !DECL_SIZE (fld)
643 || !host_integerp (DECL_FIELD_OFFSET (fld), 1)
644 || !host_integerp (DECL_SIZE (fld), 1))
647 if (AGGREGATE_TYPE_P (ft)
648 && type_internals_preclude_sra_p (ft))
655 et = TREE_TYPE (type);
657 if (AGGREGATE_TYPE_P (et))
658 return type_internals_preclude_sra_p (et);
667 /* If T is an SSA_NAME, return NULL if it is not a default def or return its
668 base variable if it is. Return T if it is not an SSA_NAME. */
671 get_ssa_base_param (tree t)
673 if (TREE_CODE (t) == SSA_NAME)
675 if (SSA_NAME_IS_DEFAULT_DEF (t))
676 return SSA_NAME_VAR (t);
683 /* Mark a dereference of BASE of distance DIST in a basic block tht STMT
684 belongs to, unless the BB has already been marked as a potentially
688 mark_parm_dereference (tree base, HOST_WIDE_INT dist, gimple stmt)
690 basic_block bb = gimple_bb (stmt);
691 int idx, parm_index = 0;
694 if (bitmap_bit_p (final_bbs, bb->index))
697 for (parm = DECL_ARGUMENTS (current_function_decl);
698 parm && parm != base;
699 parm = TREE_CHAIN (parm))
702 gcc_assert (parm_index < func_param_count);
704 idx = bb->index * func_param_count + parm_index;
705 if (bb_dereferences[idx] < dist)
706 bb_dereferences[idx] = dist;
709 /* Allocate an access structure for BASE, OFFSET and SIZE, clear it, fill in
710 the three fields. Also add it to the vector of accesses corresponding to
711 the base. Finally, return the new access. */
713 static struct access *
714 create_access_1 (tree base, HOST_WIDE_INT offset, HOST_WIDE_INT size)
716 VEC (access_p, heap) *vec;
717 struct access *access;
720 access = (struct access *) pool_alloc (access_pool);
721 memset (access, 0, sizeof (struct access));
723 access->offset = offset;
726 slot = pointer_map_contains (base_access_vec, base);
728 vec = (VEC (access_p, heap) *) *slot;
730 vec = VEC_alloc (access_p, heap, 32);
732 VEC_safe_push (access_p, heap, vec, access);
734 *((struct VEC (access_p,heap) **)
735 pointer_map_insert (base_access_vec, base)) = vec;
740 /* Create and insert access for EXPR. Return created access, or NULL if it is
743 static struct access *
744 create_access (tree expr, gimple stmt, bool write)
746 struct access *access;
747 HOST_WIDE_INT offset, size, max_size;
749 bool ptr, unscalarizable_region = false;
751 base = get_ref_base_and_extent (expr, &offset, &size, &max_size);
753 if (sra_mode == SRA_MODE_EARLY_IPA && INDIRECT_REF_P (base))
755 base = get_ssa_base_param (TREE_OPERAND (base, 0));
763 if (!DECL_P (base) || !bitmap_bit_p (candidate_bitmap, DECL_UID (base)))
766 if (sra_mode == SRA_MODE_EARLY_IPA)
768 if (size < 0 || size != max_size)
770 disqualify_candidate (base, "Encountered a variable sized access.");
773 if ((offset % BITS_PER_UNIT) != 0 || (size % BITS_PER_UNIT) != 0)
775 disqualify_candidate (base,
776 "Encountered an acces not aligned to a byte.");
781 mark_parm_dereference (base, offset + size, stmt);
785 if (size != max_size)
788 unscalarizable_region = true;
792 disqualify_candidate (base, "Encountered an unconstrained access.");
797 access = create_access_1 (base, offset, size);
799 access->type = TREE_TYPE (expr);
800 access->write = write;
801 access->grp_unscalarizable_region = unscalarizable_region;
808 /* Return true iff TYPE is a RECORD_TYPE with fields that are either of gimple
809 register types or (recursively) records with only these two kinds of fields.
810 It also returns false if any of these records has a zero-size field as its
814 type_consists_of_records_p (tree type)
817 bool last_fld_has_zero_size = false;
819 if (TREE_CODE (type) != RECORD_TYPE)
822 for (fld = TYPE_FIELDS (type); fld; fld = TREE_CHAIN (fld))
823 if (TREE_CODE (fld) == FIELD_DECL)
825 tree ft = TREE_TYPE (fld);
827 if (!is_gimple_reg_type (ft)
828 && !type_consists_of_records_p (ft))
831 last_fld_has_zero_size = tree_low_cst (DECL_SIZE (fld), 1) == 0;
834 if (last_fld_has_zero_size)
840 /* Create total_scalarization accesses for all scalar type fields in DECL that
841 must be of a RECORD_TYPE conforming to type_consists_of_records_p. BASE
842 must be the top-most VAR_DECL representing the variable, OFFSET must be the
843 offset of DECL within BASE. */
846 completely_scalarize_record (tree base, tree decl, HOST_WIDE_INT offset)
848 tree fld, decl_type = TREE_TYPE (decl);
850 for (fld = TYPE_FIELDS (decl_type); fld; fld = TREE_CHAIN (fld))
851 if (TREE_CODE (fld) == FIELD_DECL)
853 HOST_WIDE_INT pos = offset + int_bit_position (fld);
854 tree ft = TREE_TYPE (fld);
856 if (is_gimple_reg_type (ft))
858 struct access *access;
863 size = tree_low_cst (DECL_SIZE (fld), 1);
865 ok = build_ref_for_offset (&expr, TREE_TYPE (base), pos,
869 access = create_access_1 (base, pos, size);
872 access->total_scalarization = 1;
873 /* Accesses for intraprocedural SRA can have their stmt NULL. */
876 completely_scalarize_record (base, fld, pos);
881 /* Search the given tree for a declaration by skipping handled components and
882 exclude it from the candidates. */
885 disqualify_base_of_expr (tree t, const char *reason)
887 while (handled_component_p (t))
888 t = TREE_OPERAND (t, 0);
890 if (sra_mode == SRA_MODE_EARLY_IPA)
892 if (INDIRECT_REF_P (t))
893 t = TREE_OPERAND (t, 0);
894 t = get_ssa_base_param (t);
898 disqualify_candidate (t, reason);
901 /* Scan expression EXPR and create access structures for all accesses to
902 candidates for scalarization. Return the created access or NULL if none is
905 static struct access *
906 build_access_from_expr_1 (tree expr, gimple stmt, bool write)
908 struct access *ret = NULL;
911 if (TREE_CODE (expr) == BIT_FIELD_REF
912 || TREE_CODE (expr) == IMAGPART_EXPR
913 || TREE_CODE (expr) == REALPART_EXPR)
915 expr = TREE_OPERAND (expr, 0);
921 /* We need to dive through V_C_Es in order to get the size of its parameter
922 and not the result type. Ada produces such statements. We are also
923 capable of handling the topmost V_C_E but not any of those buried in other
924 handled components. */
925 if (TREE_CODE (expr) == VIEW_CONVERT_EXPR)
926 expr = TREE_OPERAND (expr, 0);
928 if (contains_view_convert_expr_p (expr))
930 disqualify_base_of_expr (expr, "V_C_E under a different handled "
935 switch (TREE_CODE (expr))
938 if (sra_mode != SRA_MODE_EARLY_IPA)
946 case ARRAY_RANGE_REF:
947 ret = create_access (expr, stmt, write);
954 if (write && partial_ref && ret)
955 ret->grp_partial_lhs = 1;
960 /* Scan expression EXPR and create access structures for all accesses to
961 candidates for scalarization. Return true if any access has been inserted.
962 STMT must be the statement from which the expression is taken, WRITE must be
963 true if the expression is a store and false otherwise. */
966 build_access_from_expr (tree expr, gimple stmt, bool write)
968 struct access *access;
970 access = build_access_from_expr_1 (expr, stmt, write);
973 /* This means the aggregate is accesses as a whole in a way other than an
974 assign statement and thus cannot be removed even if we had a scalar
975 replacement for everything. */
976 if (cannot_scalarize_away_bitmap)
977 bitmap_set_bit (cannot_scalarize_away_bitmap, DECL_UID (access->base));
983 /* Disqualify LHS and RHS for scalarization if STMT must end its basic block in
984 modes in which it matters, return true iff they have been disqualified. RHS
985 may be NULL, in that case ignore it. If we scalarize an aggregate in
986 intra-SRA we may need to add statements after each statement. This is not
987 possible if a statement unconditionally has to end the basic block. */
989 disqualify_ops_if_throwing_stmt (gimple stmt, tree lhs, tree rhs)
991 if ((sra_mode == SRA_MODE_EARLY_INTRA || sra_mode == SRA_MODE_INTRA)
992 && (stmt_can_throw_internal (stmt) || stmt_ends_bb_p (stmt)))
994 disqualify_base_of_expr (lhs, "LHS of a throwing stmt.");
996 disqualify_base_of_expr (rhs, "RHS of a throwing stmt.");
1002 /* Scan expressions occuring in STMT, create access structures for all accesses
1003 to candidates for scalarization and remove those candidates which occur in
1004 statements or expressions that prevent them from being split apart. Return
1005 true if any access has been inserted. */
1008 build_accesses_from_assign (gimple stmt)
1011 struct access *lacc, *racc;
1013 if (!gimple_assign_single_p (stmt))
1016 lhs = gimple_assign_lhs (stmt);
1017 rhs = gimple_assign_rhs1 (stmt);
1019 if (disqualify_ops_if_throwing_stmt (stmt, lhs, rhs))
1022 racc = build_access_from_expr_1 (rhs, stmt, false);
1023 lacc = build_access_from_expr_1 (lhs, stmt, true);
1027 racc->grp_assignment_read = 1;
1028 if (should_scalarize_away_bitmap && !gimple_has_volatile_ops (stmt)
1029 && !is_gimple_reg_type (racc->type))
1030 bitmap_set_bit (should_scalarize_away_bitmap, DECL_UID (racc->base));
1034 && (sra_mode == SRA_MODE_EARLY_INTRA || sra_mode == SRA_MODE_INTRA)
1035 && !lacc->grp_unscalarizable_region
1036 && !racc->grp_unscalarizable_region
1037 && AGGREGATE_TYPE_P (TREE_TYPE (lhs))
1038 /* FIXME: Turn the following line into an assert after PR 40058 is
1040 && lacc->size == racc->size
1041 && useless_type_conversion_p (lacc->type, racc->type))
1043 struct assign_link *link;
1045 link = (struct assign_link *) pool_alloc (link_pool);
1046 memset (link, 0, sizeof (struct assign_link));
1051 add_link_to_rhs (racc, link);
1054 return lacc || racc;
1057 /* Callback of walk_stmt_load_store_addr_ops visit_addr used to determine
1058 GIMPLE_ASM operands with memory constrains which cannot be scalarized. */
1061 asm_visit_addr (gimple stmt ATTRIBUTE_UNUSED, tree op,
1062 void *data ATTRIBUTE_UNUSED)
1064 op = get_base_address (op);
1067 disqualify_candidate (op, "Non-scalarizable GIMPLE_ASM operand.");
1072 /* Return true iff callsite CALL has at least as many actual arguments as there
1073 are formal parameters of the function currently processed by IPA-SRA. */
1076 callsite_has_enough_arguments_p (gimple call)
1078 return gimple_call_num_args (call) >= (unsigned) func_param_count;
1081 /* Scan function and look for interesting expressions and create access
1082 structures for them. Return true iff any access is created. */
1085 scan_function (void)
1092 gimple_stmt_iterator gsi;
1093 for (gsi = gsi_start_bb (bb); !gsi_end_p (gsi); gsi_next (&gsi))
1095 gimple stmt = gsi_stmt (gsi);
1099 if (final_bbs && stmt_can_throw_external (stmt))
1100 bitmap_set_bit (final_bbs, bb->index);
1101 switch (gimple_code (stmt))
1104 t = gimple_return_retval (stmt);
1106 ret |= build_access_from_expr (t, stmt, false);
1108 bitmap_set_bit (final_bbs, bb->index);
1112 ret |= build_accesses_from_assign (stmt);
1116 for (i = 0; i < gimple_call_num_args (stmt); i++)
1117 ret |= build_access_from_expr (gimple_call_arg (stmt, i),
1120 if (sra_mode == SRA_MODE_EARLY_IPA)
1122 tree dest = gimple_call_fndecl (stmt);
1123 int flags = gimple_call_flags (stmt);
1127 if (DECL_BUILT_IN_CLASS (dest) == BUILT_IN_NORMAL
1128 && DECL_FUNCTION_CODE (dest) == BUILT_IN_APPLY_ARGS)
1129 encountered_apply_args = true;
1130 if (cgraph_get_node (dest)
1131 == cgraph_get_node (current_function_decl))
1133 encountered_recursive_call = true;
1134 if (!callsite_has_enough_arguments_p (stmt))
1135 encountered_unchangable_recursive_call = true;
1140 && (flags & (ECF_CONST | ECF_PURE)) == 0)
1141 bitmap_set_bit (final_bbs, bb->index);
1144 t = gimple_call_lhs (stmt);
1145 if (t && !disqualify_ops_if_throwing_stmt (stmt, t, NULL))
1146 ret |= build_access_from_expr (t, stmt, true);
1150 walk_stmt_load_store_addr_ops (stmt, NULL, NULL, NULL,
1153 bitmap_set_bit (final_bbs, bb->index);
1155 for (i = 0; i < gimple_asm_ninputs (stmt); i++)
1157 t = TREE_VALUE (gimple_asm_input_op (stmt, i));
1158 ret |= build_access_from_expr (t, stmt, false);
1160 for (i = 0; i < gimple_asm_noutputs (stmt); i++)
1162 t = TREE_VALUE (gimple_asm_output_op (stmt, i));
1163 ret |= build_access_from_expr (t, stmt, true);
1176 /* Helper of QSORT function. There are pointers to accesses in the array. An
1177 access is considered smaller than another if it has smaller offset or if the
1178 offsets are the same but is size is bigger. */
1181 compare_access_positions (const void *a, const void *b)
1183 const access_p *fp1 = (const access_p *) a;
1184 const access_p *fp2 = (const access_p *) b;
1185 const access_p f1 = *fp1;
1186 const access_p f2 = *fp2;
1188 if (f1->offset != f2->offset)
1189 return f1->offset < f2->offset ? -1 : 1;
1191 if (f1->size == f2->size)
1193 if (f1->type == f2->type)
1195 /* Put any non-aggregate type before any aggregate type. */
1196 else if (!is_gimple_reg_type (f1->type)
1197 && is_gimple_reg_type (f2->type))
1199 else if (is_gimple_reg_type (f1->type)
1200 && !is_gimple_reg_type (f2->type))
1202 /* Put any complex or vector type before any other scalar type. */
1203 else if (TREE_CODE (f1->type) != COMPLEX_TYPE
1204 && TREE_CODE (f1->type) != VECTOR_TYPE
1205 && (TREE_CODE (f2->type) == COMPLEX_TYPE
1206 || TREE_CODE (f2->type) == VECTOR_TYPE))
1208 else if ((TREE_CODE (f1->type) == COMPLEX_TYPE
1209 || TREE_CODE (f1->type) == VECTOR_TYPE)
1210 && TREE_CODE (f2->type) != COMPLEX_TYPE
1211 && TREE_CODE (f2->type) != VECTOR_TYPE)
1213 /* Put the integral type with the bigger precision first. */
1214 else if (INTEGRAL_TYPE_P (f1->type)
1215 && INTEGRAL_TYPE_P (f2->type))
1216 return TYPE_PRECISION (f2->type) - TYPE_PRECISION (f1->type);
1217 /* Put any integral type with non-full precision last. */
1218 else if (INTEGRAL_TYPE_P (f1->type)
1219 && (TREE_INT_CST_LOW (TYPE_SIZE (f1->type))
1220 != TYPE_PRECISION (f1->type)))
1222 else if (INTEGRAL_TYPE_P (f2->type)
1223 && (TREE_INT_CST_LOW (TYPE_SIZE (f2->type))
1224 != TYPE_PRECISION (f2->type)))
1226 /* Stabilize the sort. */
1227 return TYPE_UID (f1->type) - TYPE_UID (f2->type);
1230 /* We want the bigger accesses first, thus the opposite operator in the next
1232 return f1->size > f2->size ? -1 : 1;
1236 /* Append a name of the declaration to the name obstack. A helper function for
1240 make_fancy_decl_name (tree decl)
1244 tree name = DECL_NAME (decl);
1246 obstack_grow (&name_obstack, IDENTIFIER_POINTER (name),
1247 IDENTIFIER_LENGTH (name));
1250 sprintf (buffer, "D%u", DECL_UID (decl));
1251 obstack_grow (&name_obstack, buffer, strlen (buffer));
1255 /* Helper for make_fancy_name. */
1258 make_fancy_name_1 (tree expr)
1265 make_fancy_decl_name (expr);
1269 switch (TREE_CODE (expr))
1272 make_fancy_name_1 (TREE_OPERAND (expr, 0));
1273 obstack_1grow (&name_obstack, '$');
1274 make_fancy_decl_name (TREE_OPERAND (expr, 1));
1278 make_fancy_name_1 (TREE_OPERAND (expr, 0));
1279 obstack_1grow (&name_obstack, '$');
1280 /* Arrays with only one element may not have a constant as their
1282 index = TREE_OPERAND (expr, 1);
1283 if (TREE_CODE (index) != INTEGER_CST)
1285 sprintf (buffer, HOST_WIDE_INT_PRINT_DEC, TREE_INT_CST_LOW (index));
1286 obstack_grow (&name_obstack, buffer, strlen (buffer));
1293 gcc_unreachable (); /* we treat these as scalars. */
1300 /* Create a human readable name for replacement variable of ACCESS. */
1303 make_fancy_name (tree expr)
1305 make_fancy_name_1 (expr);
1306 obstack_1grow (&name_obstack, '\0');
1307 return XOBFINISH (&name_obstack, char *);
1310 /* Helper function for build_ref_for_offset. */
1313 build_ref_for_offset_1 (tree *res, tree type, HOST_WIDE_INT offset,
1319 tree tr_size, index, minidx;
1320 HOST_WIDE_INT el_size;
1322 if (offset == 0 && exp_type
1323 && types_compatible_p (exp_type, type))
1326 switch (TREE_CODE (type))
1329 case QUAL_UNION_TYPE:
1331 for (fld = TYPE_FIELDS (type); fld; fld = TREE_CHAIN (fld))
1333 HOST_WIDE_INT pos, size;
1334 tree expr, *expr_ptr;
1336 if (TREE_CODE (fld) != FIELD_DECL)
1339 pos = int_bit_position (fld);
1340 gcc_assert (TREE_CODE (type) == RECORD_TYPE || pos == 0);
1341 tr_size = DECL_SIZE (fld);
1342 if (!tr_size || !host_integerp (tr_size, 1))
1344 size = tree_low_cst (tr_size, 1);
1350 else if (pos > offset || (pos + size) <= offset)
1355 expr = build3 (COMPONENT_REF, TREE_TYPE (fld), *res, fld,
1361 if (build_ref_for_offset_1 (expr_ptr, TREE_TYPE (fld),
1362 offset - pos, exp_type))
1372 tr_size = TYPE_SIZE (TREE_TYPE (type));
1373 if (!tr_size || !host_integerp (tr_size, 1))
1375 el_size = tree_low_cst (tr_size, 1);
1377 minidx = TYPE_MIN_VALUE (TYPE_DOMAIN (type));
1378 if (TREE_CODE (minidx) != INTEGER_CST || el_size == 0)
1382 index = build_int_cst (TYPE_DOMAIN (type), offset / el_size);
1383 if (!integer_zerop (minidx))
1384 index = int_const_binop (PLUS_EXPR, index, minidx, 0);
1385 *res = build4 (ARRAY_REF, TREE_TYPE (type), *res, index,
1386 NULL_TREE, NULL_TREE);
1388 offset = offset % el_size;
1389 type = TREE_TYPE (type);
1404 /* Construct an expression that would reference a part of aggregate *EXPR of
1405 type TYPE at the given OFFSET of the type EXP_TYPE. If EXPR is NULL, the
1406 function only determines whether it can build such a reference without
1407 actually doing it, otherwise, the tree it points to is unshared first and
1408 then used as a base for furhter sub-references.
1410 FIXME: Eventually this should be replaced with
1411 maybe_fold_offset_to_reference() from tree-ssa-ccp.c but that requires a
1412 minor rewrite of fold_stmt.
1416 build_ref_for_offset (tree *expr, tree type, HOST_WIDE_INT offset,
1417 tree exp_type, bool allow_ptr)
1419 location_t loc = expr ? EXPR_LOCATION (*expr) : UNKNOWN_LOCATION;
1422 *expr = unshare_expr (*expr);
1424 if (allow_ptr && POINTER_TYPE_P (type))
1426 type = TREE_TYPE (type);
1428 *expr = fold_build1_loc (loc, INDIRECT_REF, type, *expr);
1431 return build_ref_for_offset_1 (expr, type, offset, exp_type);
1434 /* Return true iff TYPE is stdarg va_list type. */
1437 is_va_list_type (tree type)
1439 return TYPE_MAIN_VARIANT (type) == TYPE_MAIN_VARIANT (va_list_type_node);
1442 /* The very first phase of intraprocedural SRA. It marks in candidate_bitmap
1443 those with type which is suitable for scalarization. */
1446 find_var_candidates (void)
1449 referenced_var_iterator rvi;
1452 FOR_EACH_REFERENCED_VAR (var, rvi)
1454 if (TREE_CODE (var) != VAR_DECL && TREE_CODE (var) != PARM_DECL)
1456 type = TREE_TYPE (var);
1458 if (!AGGREGATE_TYPE_P (type)
1459 || needs_to_live_in_memory (var)
1460 || TREE_THIS_VOLATILE (var)
1461 || !COMPLETE_TYPE_P (type)
1462 || !host_integerp (TYPE_SIZE (type), 1)
1463 || tree_low_cst (TYPE_SIZE (type), 1) == 0
1464 || type_internals_preclude_sra_p (type)
1465 /* Fix for PR 41089. tree-stdarg.c needs to have va_lists intact but
1466 we also want to schedule it rather late. Thus we ignore it in
1468 || (sra_mode == SRA_MODE_EARLY_INTRA
1469 && is_va_list_type (type)))
1472 bitmap_set_bit (candidate_bitmap, DECL_UID (var));
1474 if (dump_file && (dump_flags & TDF_DETAILS))
1476 fprintf (dump_file, "Candidate (%d): ", DECL_UID (var));
1477 print_generic_expr (dump_file, var, 0);
1478 fprintf (dump_file, "\n");
1486 /* Sort all accesses for the given variable, check for partial overlaps and
1487 return NULL if there are any. If there are none, pick a representative for
1488 each combination of offset and size and create a linked list out of them.
1489 Return the pointer to the first representative and make sure it is the first
1490 one in the vector of accesses. */
1492 static struct access *
1493 sort_and_splice_var_accesses (tree var)
1495 int i, j, access_count;
1496 struct access *res, **prev_acc_ptr = &res;
1497 VEC (access_p, heap) *access_vec;
1499 HOST_WIDE_INT low = -1, high = 0;
1501 access_vec = get_base_access_vector (var);
1504 access_count = VEC_length (access_p, access_vec);
1506 /* Sort by <OFFSET, SIZE>. */
1507 qsort (VEC_address (access_p, access_vec), access_count, sizeof (access_p),
1508 compare_access_positions);
1511 while (i < access_count)
1513 struct access *access = VEC_index (access_p, access_vec, i);
1514 bool grp_write = access->write;
1515 bool grp_read = !access->write;
1516 bool grp_assignment_read = access->grp_assignment_read;
1517 bool multiple_reads = false;
1518 bool total_scalarization = access->total_scalarization;
1519 bool grp_partial_lhs = access->grp_partial_lhs;
1520 bool first_scalar = is_gimple_reg_type (access->type);
1521 bool unscalarizable_region = access->grp_unscalarizable_region;
1523 if (first || access->offset >= high)
1526 low = access->offset;
1527 high = access->offset + access->size;
1529 else if (access->offset > low && access->offset + access->size > high)
1532 gcc_assert (access->offset >= low
1533 && access->offset + access->size <= high);
1536 while (j < access_count)
1538 struct access *ac2 = VEC_index (access_p, access_vec, j);
1539 if (ac2->offset != access->offset || ac2->size != access->size)
1546 multiple_reads = true;
1550 grp_assignment_read |= ac2->grp_assignment_read;
1551 grp_partial_lhs |= ac2->grp_partial_lhs;
1552 unscalarizable_region |= ac2->grp_unscalarizable_region;
1553 total_scalarization |= ac2->total_scalarization;
1554 relink_to_new_repr (access, ac2);
1556 /* If there are both aggregate-type and scalar-type accesses with
1557 this combination of size and offset, the comparison function
1558 should have put the scalars first. */
1559 gcc_assert (first_scalar || !is_gimple_reg_type (ac2->type));
1560 ac2->group_representative = access;
1566 access->group_representative = access;
1567 access->grp_write = grp_write;
1568 access->grp_read = grp_read;
1569 access->grp_assignment_read = grp_assignment_read;
1570 access->grp_hint = multiple_reads || total_scalarization;
1571 access->grp_partial_lhs = grp_partial_lhs;
1572 access->grp_unscalarizable_region = unscalarizable_region;
1573 if (access->first_link)
1574 add_access_to_work_queue (access);
1576 *prev_acc_ptr = access;
1577 prev_acc_ptr = &access->next_grp;
1580 gcc_assert (res == VEC_index (access_p, access_vec, 0));
1584 /* Create a variable for the given ACCESS which determines the type, name and a
1585 few other properties. Return the variable declaration and store it also to
1586 ACCESS->replacement. */
1589 create_access_replacement (struct access *access)
1593 repl = create_tmp_var (access->type, "SR");
1595 add_referenced_var (repl);
1596 mark_sym_for_renaming (repl);
1598 if (!access->grp_partial_lhs
1599 && (TREE_CODE (access->type) == COMPLEX_TYPE
1600 || TREE_CODE (access->type) == VECTOR_TYPE))
1601 DECL_GIMPLE_REG_P (repl) = 1;
1603 DECL_SOURCE_LOCATION (repl) = DECL_SOURCE_LOCATION (access->base);
1604 DECL_ARTIFICIAL (repl) = 1;
1605 DECL_IGNORED_P (repl) = DECL_IGNORED_P (access->base);
1607 if (DECL_NAME (access->base)
1608 && !DECL_IGNORED_P (access->base)
1609 && !DECL_ARTIFICIAL (access->base))
1611 char *pretty_name = make_fancy_name (access->expr);
1612 tree debug_expr = unshare_expr (access->expr), d;
1614 DECL_NAME (repl) = get_identifier (pretty_name);
1615 obstack_free (&name_obstack, pretty_name);
1617 /* Get rid of any SSA_NAMEs embedded in debug_expr,
1618 as DECL_DEBUG_EXPR isn't considered when looking for still
1619 used SSA_NAMEs and thus they could be freed. All debug info
1620 generation cares is whether something is constant or variable
1621 and that get_ref_base_and_extent works properly on the
1623 for (d = debug_expr; handled_component_p (d); d = TREE_OPERAND (d, 0))
1624 switch (TREE_CODE (d))
1627 case ARRAY_RANGE_REF:
1628 if (TREE_OPERAND (d, 1)
1629 && TREE_CODE (TREE_OPERAND (d, 1)) == SSA_NAME)
1630 TREE_OPERAND (d, 1) = SSA_NAME_VAR (TREE_OPERAND (d, 1));
1631 if (TREE_OPERAND (d, 3)
1632 && TREE_CODE (TREE_OPERAND (d, 3)) == SSA_NAME)
1633 TREE_OPERAND (d, 3) = SSA_NAME_VAR (TREE_OPERAND (d, 3));
1636 if (TREE_OPERAND (d, 2)
1637 && TREE_CODE (TREE_OPERAND (d, 2)) == SSA_NAME)
1638 TREE_OPERAND (d, 2) = SSA_NAME_VAR (TREE_OPERAND (d, 2));
1643 SET_DECL_DEBUG_EXPR (repl, debug_expr);
1644 DECL_DEBUG_EXPR_IS_FROM (repl) = 1;
1645 TREE_NO_WARNING (repl) = TREE_NO_WARNING (access->base);
1648 TREE_NO_WARNING (repl) = 1;
1652 fprintf (dump_file, "Created a replacement for ");
1653 print_generic_expr (dump_file, access->base, 0);
1654 fprintf (dump_file, " offset: %u, size: %u: ",
1655 (unsigned) access->offset, (unsigned) access->size);
1656 print_generic_expr (dump_file, repl, 0);
1657 fprintf (dump_file, "\n");
1659 sra_stats.replacements++;
1664 /* Return ACCESS scalar replacement, create it if it does not exist yet. */
1667 get_access_replacement (struct access *access)
1669 gcc_assert (access->grp_to_be_replaced);
1671 if (!access->replacement_decl)
1672 access->replacement_decl = create_access_replacement (access);
1673 return access->replacement_decl;
1676 /* Build a subtree of accesses rooted in *ACCESS, and move the pointer in the
1677 linked list along the way. Stop when *ACCESS is NULL or the access pointed
1678 to it is not "within" the root. */
1681 build_access_subtree (struct access **access)
1683 struct access *root = *access, *last_child = NULL;
1684 HOST_WIDE_INT limit = root->offset + root->size;
1686 *access = (*access)->next_grp;
1687 while (*access && (*access)->offset + (*access)->size <= limit)
1690 root->first_child = *access;
1692 last_child->next_sibling = *access;
1693 last_child = *access;
1695 build_access_subtree (access);
1699 /* Build a tree of access representatives, ACCESS is the pointer to the first
1700 one, others are linked in a list by the next_grp field. Decide about scalar
1701 replacements on the way, return true iff any are to be created. */
1704 build_access_trees (struct access *access)
1708 struct access *root = access;
1710 build_access_subtree (&access);
1711 root->next_grp = access;
1715 /* Return true if expr contains some ARRAY_REFs into a variable bounded
1719 expr_with_var_bounded_array_refs_p (tree expr)
1721 while (handled_component_p (expr))
1723 if (TREE_CODE (expr) == ARRAY_REF
1724 && !host_integerp (array_ref_low_bound (expr), 0))
1726 expr = TREE_OPERAND (expr, 0);
1731 enum mark_read_status { SRA_MR_NOT_READ, SRA_MR_READ, SRA_MR_ASSIGN_READ};
1733 /* Analyze the subtree of accesses rooted in ROOT, scheduling replacements when
1734 both seeming beneficial and when ALLOW_REPLACEMENTS allows it. Also set all
1735 sorts of access flags appropriately along the way, notably always set
1736 grp_read and grp_assign_read according to MARK_READ and grp_write when
1737 MARK_WRITE is true. */
1740 analyze_access_subtree (struct access *root, bool allow_replacements,
1741 enum mark_read_status mark_read, bool mark_write)
1743 struct access *child;
1744 HOST_WIDE_INT limit = root->offset + root->size;
1745 HOST_WIDE_INT covered_to = root->offset;
1746 bool scalar = is_gimple_reg_type (root->type);
1747 bool hole = false, sth_created = false;
1748 bool direct_read = root->grp_read;
1750 if (mark_read == SRA_MR_ASSIGN_READ)
1753 root->grp_assignment_read = 1;
1755 if (mark_read == SRA_MR_READ)
1757 else if (root->grp_assignment_read)
1758 mark_read = SRA_MR_ASSIGN_READ;
1759 else if (root->grp_read)
1760 mark_read = SRA_MR_READ;
1763 root->grp_write = true;
1764 else if (root->grp_write)
1767 if (root->grp_unscalarizable_region)
1768 allow_replacements = false;
1770 if (allow_replacements && expr_with_var_bounded_array_refs_p (root->expr))
1771 allow_replacements = false;
1773 for (child = root->first_child; child; child = child->next_sibling)
1775 if (!hole && child->offset < covered_to)
1778 covered_to += child->size;
1780 sth_created |= analyze_access_subtree (child, allow_replacements,
1781 mark_read, mark_write);
1783 root->grp_unscalarized_data |= child->grp_unscalarized_data;
1784 hole |= !child->grp_covered;
1787 if (allow_replacements && scalar && !root->first_child
1789 || (root->grp_write && (direct_read || root->grp_assignment_read)))
1790 /* We must not ICE later on when trying to build an access to the
1791 original data within the aggregate even when it is impossible to do in
1792 a defined way like in the PR 42703 testcase. Therefore we check
1793 pre-emptively here that we will be able to do that. */
1794 && build_ref_for_offset (NULL, TREE_TYPE (root->base), root->offset,
1797 if (dump_file && (dump_flags & TDF_DETAILS))
1799 fprintf (dump_file, "Marking ");
1800 print_generic_expr (dump_file, root->base, 0);
1801 fprintf (dump_file, " offset: %u, size: %u: ",
1802 (unsigned) root->offset, (unsigned) root->size);
1803 fprintf (dump_file, " to be replaced.\n");
1806 root->grp_to_be_replaced = 1;
1810 else if (covered_to < limit)
1813 if (sth_created && !hole)
1815 root->grp_covered = 1;
1818 if (root->grp_write || TREE_CODE (root->base) == PARM_DECL)
1819 root->grp_unscalarized_data = 1; /* not covered and written to */
1825 /* Analyze all access trees linked by next_grp by the means of
1826 analyze_access_subtree. */
1828 analyze_access_trees (struct access *access)
1834 if (analyze_access_subtree (access, true, SRA_MR_NOT_READ, false))
1836 access = access->next_grp;
1842 /* Return true iff a potential new child of LACC at offset OFFSET and with size
1843 SIZE would conflict with an already existing one. If exactly such a child
1844 already exists in LACC, store a pointer to it in EXACT_MATCH. */
1847 child_would_conflict_in_lacc (struct access *lacc, HOST_WIDE_INT norm_offset,
1848 HOST_WIDE_INT size, struct access **exact_match)
1850 struct access *child;
1852 for (child = lacc->first_child; child; child = child->next_sibling)
1854 if (child->offset == norm_offset && child->size == size)
1856 *exact_match = child;
1860 if (child->offset < norm_offset + size
1861 && child->offset + child->size > norm_offset)
1868 /* Create a new child access of PARENT, with all properties just like MODEL
1869 except for its offset and with its grp_write false and grp_read true.
1870 Return the new access or NULL if it cannot be created. Note that this access
1871 is created long after all splicing and sorting, it's not located in any
1872 access vector and is automatically a representative of its group. */
1874 static struct access *
1875 create_artificial_child_access (struct access *parent, struct access *model,
1876 HOST_WIDE_INT new_offset)
1878 struct access *access;
1879 struct access **child;
1880 tree expr = parent->base;;
1882 gcc_assert (!model->grp_unscalarizable_region);
1884 if (!build_ref_for_offset (&expr, TREE_TYPE (expr), new_offset,
1885 model->type, false))
1888 access = (struct access *) pool_alloc (access_pool);
1889 memset (access, 0, sizeof (struct access));
1890 access->base = parent->base;
1891 access->expr = expr;
1892 access->offset = new_offset;
1893 access->size = model->size;
1894 access->type = model->type;
1895 access->grp_write = true;
1896 access->grp_read = false;
1898 child = &parent->first_child;
1899 while (*child && (*child)->offset < new_offset)
1900 child = &(*child)->next_sibling;
1902 access->next_sibling = *child;
1909 /* Propagate all subaccesses of RACC across an assignment link to LACC. Return
1910 true if any new subaccess was created. Additionally, if RACC is a scalar
1911 access but LACC is not, change the type of the latter, if possible. */
1914 propagate_subaccesses_across_link (struct access *lacc, struct access *racc)
1916 struct access *rchild;
1917 HOST_WIDE_INT norm_delta = lacc->offset - racc->offset;
1920 if (is_gimple_reg_type (lacc->type)
1921 || lacc->grp_unscalarizable_region
1922 || racc->grp_unscalarizable_region)
1925 if (!lacc->first_child && !racc->first_child
1926 && is_gimple_reg_type (racc->type))
1928 tree t = lacc->base;
1930 if (build_ref_for_offset (&t, TREE_TYPE (t), lacc->offset, racc->type,
1934 lacc->type = racc->type;
1939 for (rchild = racc->first_child; rchild; rchild = rchild->next_sibling)
1941 struct access *new_acc = NULL;
1942 HOST_WIDE_INT norm_offset = rchild->offset + norm_delta;
1944 if (rchild->grp_unscalarizable_region)
1947 if (child_would_conflict_in_lacc (lacc, norm_offset, rchild->size,
1952 rchild->grp_hint = 1;
1953 new_acc->grp_hint |= new_acc->grp_read;
1954 if (rchild->first_child)
1955 ret |= propagate_subaccesses_across_link (new_acc, rchild);
1960 /* If a (part of) a union field is on the RHS of an assignment, it can
1961 have sub-accesses which do not make sense on the LHS (PR 40351).
1962 Check that this is not the case. */
1963 if (!build_ref_for_offset (NULL, TREE_TYPE (lacc->base), norm_offset,
1964 rchild->type, false))
1967 rchild->grp_hint = 1;
1968 new_acc = create_artificial_child_access (lacc, rchild, norm_offset);
1972 if (racc->first_child)
1973 propagate_subaccesses_across_link (new_acc, rchild);
1980 /* Propagate all subaccesses across assignment links. */
1983 propagate_all_subaccesses (void)
1985 while (work_queue_head)
1987 struct access *racc = pop_access_from_work_queue ();
1988 struct assign_link *link;
1990 gcc_assert (racc->first_link);
1992 for (link = racc->first_link; link; link = link->next)
1994 struct access *lacc = link->lacc;
1996 if (!bitmap_bit_p (candidate_bitmap, DECL_UID (lacc->base)))
1998 lacc = lacc->group_representative;
1999 if (propagate_subaccesses_across_link (lacc, racc)
2000 && lacc->first_link)
2001 add_access_to_work_queue (lacc);
2006 /* Go through all accesses collected throughout the (intraprocedural) analysis
2007 stage, exclude overlapping ones, identify representatives and build trees
2008 out of them, making decisions about scalarization on the way. Return true
2009 iff there are any to-be-scalarized variables after this stage. */
2012 analyze_all_variable_accesses (void)
2015 bitmap tmp = BITMAP_ALLOC (NULL);
2017 unsigned i, max_total_scalarization_size;
2019 max_total_scalarization_size = UNITS_PER_WORD * BITS_PER_UNIT
2020 * MOVE_RATIO (optimize_function_for_speed_p (cfun));
2022 EXECUTE_IF_SET_IN_BITMAP (candidate_bitmap, 0, i, bi)
2023 if (bitmap_bit_p (should_scalarize_away_bitmap, i)
2024 && !bitmap_bit_p (cannot_scalarize_away_bitmap, i))
2026 tree var = referenced_var (i);
2028 if (TREE_CODE (var) == VAR_DECL
2029 && ((unsigned) tree_low_cst (TYPE_SIZE (TREE_TYPE (var)), 1)
2030 <= max_total_scalarization_size)
2031 && type_consists_of_records_p (TREE_TYPE (var)))
2033 completely_scalarize_record (var, var, 0);
2034 if (dump_file && (dump_flags & TDF_DETAILS))
2036 fprintf (dump_file, "Will attempt to totally scalarize ");
2037 print_generic_expr (dump_file, var, 0);
2038 fprintf (dump_file, " (UID: %u): \n", DECL_UID (var));
2043 bitmap_copy (tmp, candidate_bitmap);
2044 EXECUTE_IF_SET_IN_BITMAP (tmp, 0, i, bi)
2046 tree var = referenced_var (i);
2047 struct access *access;
2049 access = sort_and_splice_var_accesses (var);
2051 build_access_trees (access);
2053 disqualify_candidate (var,
2054 "No or inhibitingly overlapping accesses.");
2057 propagate_all_subaccesses ();
2059 bitmap_copy (tmp, candidate_bitmap);
2060 EXECUTE_IF_SET_IN_BITMAP (tmp, 0, i, bi)
2062 tree var = referenced_var (i);
2063 struct access *access = get_first_repr_for_decl (var);
2065 if (analyze_access_trees (access))
2068 if (dump_file && (dump_flags & TDF_DETAILS))
2070 fprintf (dump_file, "\nAccess trees for ");
2071 print_generic_expr (dump_file, var, 0);
2072 fprintf (dump_file, " (UID: %u): \n", DECL_UID (var));
2073 dump_access_tree (dump_file, access);
2074 fprintf (dump_file, "\n");
2078 disqualify_candidate (var, "No scalar replacements to be created.");
2085 statistics_counter_event (cfun, "Scalarized aggregates", res);
2092 /* Return true iff a reference statement into aggregate AGG can be built for
2093 every single to-be-replaced accesses that is a child of ACCESS, its sibling
2094 or a child of its sibling. TOP_OFFSET is the offset from the processed
2095 access subtree that has to be subtracted from offset of each access. */
2098 ref_expr_for_all_replacements_p (struct access *access, tree agg,
2099 HOST_WIDE_INT top_offset)
2103 if (access->grp_to_be_replaced
2104 && !build_ref_for_offset (NULL, TREE_TYPE (agg),
2105 access->offset - top_offset,
2106 access->type, false))
2109 if (access->first_child
2110 && !ref_expr_for_all_replacements_p (access->first_child, agg,
2114 access = access->next_sibling;
2121 /* Generate statements copying scalar replacements of accesses within a subtree
2122 into or out of AGG. ACCESS is the first child of the root of the subtree to
2123 be processed. AGG is an aggregate type expression (can be a declaration but
2124 does not have to be, it can for example also be an indirect_ref).
2125 TOP_OFFSET is the offset of the processed subtree which has to be subtracted
2126 from offsets of individual accesses to get corresponding offsets for AGG.
2127 If CHUNK_SIZE is non-null, copy only replacements in the interval
2128 <start_offset, start_offset + chunk_size>, otherwise copy all. GSI is a
2129 statement iterator used to place the new statements. WRITE should be true
2130 when the statements should write from AGG to the replacement and false if
2131 vice versa. if INSERT_AFTER is true, new statements will be added after the
2132 current statement in GSI, they will be added before the statement
2136 generate_subtree_copies (struct access *access, tree agg,
2137 HOST_WIDE_INT top_offset,
2138 HOST_WIDE_INT start_offset, HOST_WIDE_INT chunk_size,
2139 gimple_stmt_iterator *gsi, bool write,
2146 if (chunk_size && access->offset >= start_offset + chunk_size)
2149 if (access->grp_to_be_replaced
2151 || access->offset + access->size > start_offset))
2153 tree repl = get_access_replacement (access);
2157 ref_found = build_ref_for_offset (&expr, TREE_TYPE (agg),
2158 access->offset - top_offset,
2159 access->type, false);
2160 gcc_assert (ref_found);
2164 if (access->grp_partial_lhs)
2165 expr = force_gimple_operand_gsi (gsi, expr, true, NULL_TREE,
2167 insert_after ? GSI_NEW_STMT
2169 stmt = gimple_build_assign (repl, expr);
2173 TREE_NO_WARNING (repl) = 1;
2174 if (access->grp_partial_lhs)
2175 repl = force_gimple_operand_gsi (gsi, repl, true, NULL_TREE,
2177 insert_after ? GSI_NEW_STMT
2179 stmt = gimple_build_assign (expr, repl);
2183 gsi_insert_after (gsi, stmt, GSI_NEW_STMT);
2185 gsi_insert_before (gsi, stmt, GSI_SAME_STMT);
2187 sra_stats.subtree_copies++;
2190 if (access->first_child)
2191 generate_subtree_copies (access->first_child, agg, top_offset,
2192 start_offset, chunk_size, gsi,
2193 write, insert_after);
2195 access = access->next_sibling;
2200 /* Assign zero to all scalar replacements in an access subtree. ACCESS is the
2201 the root of the subtree to be processed. GSI is the statement iterator used
2202 for inserting statements which are added after the current statement if
2203 INSERT_AFTER is true or before it otherwise. */
2206 init_subtree_with_zero (struct access *access, gimple_stmt_iterator *gsi,
2210 struct access *child;
2212 if (access->grp_to_be_replaced)
2216 stmt = gimple_build_assign (get_access_replacement (access),
2217 fold_convert (access->type,
2218 integer_zero_node));
2220 gsi_insert_after (gsi, stmt, GSI_NEW_STMT);
2222 gsi_insert_before (gsi, stmt, GSI_SAME_STMT);
2226 for (child = access->first_child; child; child = child->next_sibling)
2227 init_subtree_with_zero (child, gsi, insert_after);
2230 /* Search for an access representative for the given expression EXPR and
2231 return it or NULL if it cannot be found. */
2233 static struct access *
2234 get_access_for_expr (tree expr)
2236 HOST_WIDE_INT offset, size, max_size;
2239 /* FIXME: This should not be necessary but Ada produces V_C_Es with a type of
2240 a different size than the size of its argument and we need the latter
2242 if (TREE_CODE (expr) == VIEW_CONVERT_EXPR)
2243 expr = TREE_OPERAND (expr, 0);
2245 base = get_ref_base_and_extent (expr, &offset, &size, &max_size);
2246 if (max_size == -1 || !DECL_P (base))
2249 if (!bitmap_bit_p (candidate_bitmap, DECL_UID (base)))
2252 return get_var_base_offset_size_access (base, offset, max_size);
2255 /* Replace the expression EXPR with a scalar replacement if there is one and
2256 generate other statements to do type conversion or subtree copying if
2257 necessary. GSI is used to place newly created statements, WRITE is true if
2258 the expression is being written to (it is on a LHS of a statement or output
2259 in an assembly statement). */
2262 sra_modify_expr (tree *expr, gimple_stmt_iterator *gsi, bool write)
2264 struct access *access;
2267 if (TREE_CODE (*expr) == BIT_FIELD_REF)
2270 expr = &TREE_OPERAND (*expr, 0);
2275 if (TREE_CODE (*expr) == REALPART_EXPR || TREE_CODE (*expr) == IMAGPART_EXPR)
2276 expr = &TREE_OPERAND (*expr, 0);
2277 access = get_access_for_expr (*expr);
2280 type = TREE_TYPE (*expr);
2282 if (access->grp_to_be_replaced)
2284 tree repl = get_access_replacement (access);
2285 /* If we replace a non-register typed access simply use the original
2286 access expression to extract the scalar component afterwards.
2287 This happens if scalarizing a function return value or parameter
2288 like in gcc.c-torture/execute/20041124-1.c, 20050316-1.c and
2289 gcc.c-torture/compile/20011217-1.c.
2291 We also want to use this when accessing a complex or vector which can
2292 be accessed as a different type too, potentially creating a need for
2293 type conversion (see PR42196) and when scalarized unions are involved
2294 in assembler statements (see PR42398). */
2295 if (!useless_type_conversion_p (type, access->type))
2297 tree ref = access->base;
2300 ok = build_ref_for_offset (&ref, TREE_TYPE (ref),
2301 access->offset, access->type, false);
2308 if (access->grp_partial_lhs)
2309 ref = force_gimple_operand_gsi (gsi, ref, true, NULL_TREE,
2310 false, GSI_NEW_STMT);
2311 stmt = gimple_build_assign (repl, ref);
2312 gsi_insert_after (gsi, stmt, GSI_NEW_STMT);
2318 if (access->grp_partial_lhs)
2319 repl = force_gimple_operand_gsi (gsi, repl, true, NULL_TREE,
2320 true, GSI_SAME_STMT);
2321 stmt = gimple_build_assign (ref, repl);
2322 gsi_insert_before (gsi, stmt, GSI_SAME_STMT);
2330 if (access->first_child)
2332 HOST_WIDE_INT start_offset, chunk_size;
2334 && host_integerp (TREE_OPERAND (bfr, 1), 1)
2335 && host_integerp (TREE_OPERAND (bfr, 2), 1))
2337 chunk_size = tree_low_cst (TREE_OPERAND (bfr, 1), 1);
2338 start_offset = access->offset
2339 + tree_low_cst (TREE_OPERAND (bfr, 2), 1);
2342 start_offset = chunk_size = 0;
2344 generate_subtree_copies (access->first_child, access->base, 0,
2345 start_offset, chunk_size, gsi, write, write);
2350 /* Where scalar replacements of the RHS have been written to when a replacement
2351 of a LHS of an assigments cannot be direclty loaded from a replacement of
2353 enum unscalarized_data_handling { SRA_UDH_NONE, /* Nothing done so far. */
2354 SRA_UDH_RIGHT, /* Data flushed to the RHS. */
2355 SRA_UDH_LEFT }; /* Data flushed to the LHS. */
2357 /* Store all replacements in the access tree rooted in TOP_RACC either to their
2358 base aggregate if there are unscalarized data or directly to LHS
2361 static enum unscalarized_data_handling
2362 handle_unscalarized_data_in_subtree (struct access *top_racc, tree lhs,
2363 gimple_stmt_iterator *gsi)
2365 if (top_racc->grp_unscalarized_data)
2367 generate_subtree_copies (top_racc->first_child, top_racc->base, 0, 0, 0,
2369 return SRA_UDH_RIGHT;
2373 generate_subtree_copies (top_racc->first_child, lhs, top_racc->offset,
2374 0, 0, gsi, false, false);
2375 return SRA_UDH_LEFT;
2380 /* Try to generate statements to load all sub-replacements in an access
2381 (sub)tree (LACC is the first child) from scalar replacements in the TOP_RACC
2382 (sub)tree. If that is not possible, refresh the TOP_RACC base aggregate and
2383 load the accesses from it. LEFT_OFFSET is the offset of the left whole
2384 subtree being copied, RIGHT_OFFSET is the same thing for the right subtree.
2385 GSI is stmt iterator used for statement insertions. *REFRESHED is true iff
2386 the rhs top aggregate has already been refreshed by contents of its scalar
2387 reductions and is set to true if this function has to do it. */
2390 load_assign_lhs_subreplacements (struct access *lacc, struct access *top_racc,
2391 HOST_WIDE_INT left_offset,
2392 HOST_WIDE_INT right_offset,
2393 gimple_stmt_iterator *old_gsi,
2394 gimple_stmt_iterator *new_gsi,
2395 enum unscalarized_data_handling *refreshed,
2398 location_t loc = EXPR_LOCATION (lacc->expr);
2401 if (lacc->grp_to_be_replaced)
2403 struct access *racc;
2404 HOST_WIDE_INT offset = lacc->offset - left_offset + right_offset;
2408 racc = find_access_in_subtree (top_racc, offset, lacc->size);
2409 if (racc && racc->grp_to_be_replaced)
2411 rhs = get_access_replacement (racc);
2412 if (!useless_type_conversion_p (lacc->type, racc->type))
2413 rhs = fold_build1_loc (loc, VIEW_CONVERT_EXPR, lacc->type, rhs);
2417 /* No suitable access on the right hand side, need to load from
2418 the aggregate. See if we have to update it first... */
2419 if (*refreshed == SRA_UDH_NONE)
2420 *refreshed = handle_unscalarized_data_in_subtree (top_racc,
2423 if (*refreshed == SRA_UDH_LEFT)
2428 repl_found = build_ref_for_offset (&rhs, TREE_TYPE (rhs),
2429 lacc->offset, lacc->type,
2431 gcc_assert (repl_found);
2437 rhs = top_racc->base;
2438 repl_found = build_ref_for_offset (&rhs,
2439 TREE_TYPE (top_racc->base),
2440 offset, lacc->type, false);
2441 gcc_assert (repl_found);
2445 stmt = gimple_build_assign (get_access_replacement (lacc), rhs);
2446 gsi_insert_after (new_gsi, stmt, GSI_NEW_STMT);
2448 sra_stats.subreplacements++;
2450 else if (*refreshed == SRA_UDH_NONE
2451 && lacc->grp_read && !lacc->grp_covered)
2452 *refreshed = handle_unscalarized_data_in_subtree (top_racc, lhs,
2455 if (lacc->first_child)
2456 load_assign_lhs_subreplacements (lacc->first_child, top_racc,
2457 left_offset, right_offset,
2458 old_gsi, new_gsi, refreshed, lhs);
2459 lacc = lacc->next_sibling;
2464 /* Result code for SRA assignment modification. */
2465 enum assignment_mod_result { SRA_AM_NONE, /* nothing done for the stmt */
2466 SRA_AM_MODIFIED, /* stmt changed but not
2468 SRA_AM_REMOVED }; /* stmt eliminated */
2470 /* Modify assignments with a CONSTRUCTOR on their RHS. STMT contains a pointer
2471 to the assignment and GSI is the statement iterator pointing at it. Returns
2472 the same values as sra_modify_assign. */
2474 static enum assignment_mod_result
2475 sra_modify_constructor_assign (gimple *stmt, gimple_stmt_iterator *gsi)
2477 tree lhs = gimple_assign_lhs (*stmt);
2480 acc = get_access_for_expr (lhs);
2484 if (VEC_length (constructor_elt,
2485 CONSTRUCTOR_ELTS (gimple_assign_rhs1 (*stmt))) > 0)
2487 /* I have never seen this code path trigger but if it can happen the
2488 following should handle it gracefully. */
2489 if (access_has_children_p (acc))
2490 generate_subtree_copies (acc->first_child, acc->base, 0, 0, 0, gsi,
2492 return SRA_AM_MODIFIED;
2495 if (acc->grp_covered)
2497 init_subtree_with_zero (acc, gsi, false);
2498 unlink_stmt_vdef (*stmt);
2499 gsi_remove (gsi, true);
2500 return SRA_AM_REMOVED;
2504 init_subtree_with_zero (acc, gsi, true);
2505 return SRA_AM_MODIFIED;
2509 /* Create a new suitable default definition SSA_NAME and replace all uses of
2513 replace_uses_with_default_def_ssa_name (tree ssa)
2515 tree repl, decl = SSA_NAME_VAR (ssa);
2516 if (TREE_CODE (decl) == PARM_DECL)
2518 tree tmp = create_tmp_reg (TREE_TYPE (decl), "SR");
2521 add_referenced_var (tmp);
2522 repl = make_ssa_name (tmp, gimple_build_nop ());
2523 set_default_def (tmp, repl);
2527 repl = gimple_default_def (cfun, decl);
2530 repl = make_ssa_name (decl, gimple_build_nop ());
2531 set_default_def (decl, repl);
2535 replace_uses_by (ssa, repl);
2538 /* Examine both sides of the assignment statement pointed to by STMT, replace
2539 them with a scalare replacement if there is one and generate copying of
2540 replacements if scalarized aggregates have been used in the assignment. GSI
2541 is used to hold generated statements for type conversions and subtree
2544 static enum assignment_mod_result
2545 sra_modify_assign (gimple *stmt, gimple_stmt_iterator *gsi)
2547 struct access *lacc, *racc;
2549 bool modify_this_stmt = false;
2550 bool force_gimple_rhs = false;
2551 location_t loc = gimple_location (*stmt);
2552 gimple_stmt_iterator orig_gsi = *gsi;
2554 if (!gimple_assign_single_p (*stmt))
2556 lhs = gimple_assign_lhs (*stmt);
2557 rhs = gimple_assign_rhs1 (*stmt);
2559 if (TREE_CODE (rhs) == CONSTRUCTOR)
2560 return sra_modify_constructor_assign (stmt, gsi);
2562 if (TREE_CODE (rhs) == REALPART_EXPR || TREE_CODE (lhs) == REALPART_EXPR
2563 || TREE_CODE (rhs) == IMAGPART_EXPR || TREE_CODE (lhs) == IMAGPART_EXPR
2564 || TREE_CODE (rhs) == BIT_FIELD_REF || TREE_CODE (lhs) == BIT_FIELD_REF)
2566 modify_this_stmt = sra_modify_expr (gimple_assign_rhs1_ptr (*stmt),
2568 modify_this_stmt |= sra_modify_expr (gimple_assign_lhs_ptr (*stmt),
2570 return modify_this_stmt ? SRA_AM_MODIFIED : SRA_AM_NONE;
2573 lacc = get_access_for_expr (lhs);
2574 racc = get_access_for_expr (rhs);
2578 if (lacc && lacc->grp_to_be_replaced)
2580 lhs = get_access_replacement (lacc);
2581 gimple_assign_set_lhs (*stmt, lhs);
2582 modify_this_stmt = true;
2583 if (lacc->grp_partial_lhs)
2584 force_gimple_rhs = true;
2588 if (racc && racc->grp_to_be_replaced)
2590 rhs = get_access_replacement (racc);
2591 modify_this_stmt = true;
2592 if (racc->grp_partial_lhs)
2593 force_gimple_rhs = true;
2597 if (modify_this_stmt)
2599 if (!useless_type_conversion_p (TREE_TYPE (lhs), TREE_TYPE (rhs)))
2601 /* If we can avoid creating a VIEW_CONVERT_EXPR do so.
2602 ??? This should move to fold_stmt which we simply should
2603 call after building a VIEW_CONVERT_EXPR here. */
2604 if (AGGREGATE_TYPE_P (TREE_TYPE (lhs))
2605 && !access_has_children_p (lacc))
2608 if (build_ref_for_offset (&expr, TREE_TYPE (lhs), 0,
2609 TREE_TYPE (rhs), false))
2612 gimple_assign_set_lhs (*stmt, expr);
2615 else if (AGGREGATE_TYPE_P (TREE_TYPE (rhs))
2616 && !access_has_children_p (racc))
2619 if (build_ref_for_offset (&expr, TREE_TYPE (rhs), 0,
2620 TREE_TYPE (lhs), false))
2623 if (!useless_type_conversion_p (TREE_TYPE (lhs), TREE_TYPE (rhs)))
2625 rhs = fold_build1_loc (loc, VIEW_CONVERT_EXPR, TREE_TYPE (lhs), rhs);
2626 if (is_gimple_reg_type (TREE_TYPE (lhs))
2627 && TREE_CODE (lhs) != SSA_NAME)
2628 force_gimple_rhs = true;
2633 /* From this point on, the function deals with assignments in between
2634 aggregates when at least one has scalar reductions of some of its
2635 components. There are three possible scenarios: Both the LHS and RHS have
2636 to-be-scalarized components, 2) only the RHS has or 3) only the LHS has.
2638 In the first case, we would like to load the LHS components from RHS
2639 components whenever possible. If that is not possible, we would like to
2640 read it directly from the RHS (after updating it by storing in it its own
2641 components). If there are some necessary unscalarized data in the LHS,
2642 those will be loaded by the original assignment too. If neither of these
2643 cases happen, the original statement can be removed. Most of this is done
2644 by load_assign_lhs_subreplacements.
2646 In the second case, we would like to store all RHS scalarized components
2647 directly into LHS and if they cover the aggregate completely, remove the
2648 statement too. In the third case, we want the LHS components to be loaded
2649 directly from the RHS (DSE will remove the original statement if it
2652 This is a bit complex but manageable when types match and when unions do
2653 not cause confusion in a way that we cannot really load a component of LHS
2654 from the RHS or vice versa (the access representing this level can have
2655 subaccesses that are accessible only through a different union field at a
2656 higher level - different from the one used in the examined expression).
2659 Therefore, I specially handle a fourth case, happening when there is a
2660 specific type cast or it is impossible to locate a scalarized subaccess on
2661 the other side of the expression. If that happens, I simply "refresh" the
2662 RHS by storing in it is scalarized components leave the original statement
2663 there to do the copying and then load the scalar replacements of the LHS.
2664 This is what the first branch does. */
2666 if (gimple_has_volatile_ops (*stmt)
2667 || contains_view_convert_expr_p (rhs)
2668 || contains_view_convert_expr_p (lhs)
2669 || (access_has_children_p (racc)
2670 && !ref_expr_for_all_replacements_p (racc, lhs, racc->offset))
2671 || (access_has_children_p (lacc)
2672 && !ref_expr_for_all_replacements_p (lacc, rhs, lacc->offset)))
2674 if (access_has_children_p (racc))
2675 generate_subtree_copies (racc->first_child, racc->base, 0, 0, 0,
2677 if (access_has_children_p (lacc))
2678 generate_subtree_copies (lacc->first_child, lacc->base, 0, 0, 0,
2680 sra_stats.separate_lhs_rhs_handling++;
2684 if (access_has_children_p (lacc) && access_has_children_p (racc))
2686 gimple_stmt_iterator orig_gsi = *gsi;
2687 enum unscalarized_data_handling refreshed;
2689 if (lacc->grp_read && !lacc->grp_covered)
2690 refreshed = handle_unscalarized_data_in_subtree (racc, lhs, gsi);
2692 refreshed = SRA_UDH_NONE;
2694 load_assign_lhs_subreplacements (lacc->first_child, racc,
2695 lacc->offset, racc->offset,
2696 &orig_gsi, gsi, &refreshed, lhs);
2697 if (refreshed != SRA_UDH_RIGHT)
2699 if (*stmt == gsi_stmt (*gsi))
2702 unlink_stmt_vdef (*stmt);
2703 gsi_remove (&orig_gsi, true);
2704 sra_stats.deleted++;
2705 return SRA_AM_REMOVED;
2712 if (!racc->grp_to_be_replaced && !racc->grp_unscalarized_data)
2714 if (racc->first_child)
2715 generate_subtree_copies (racc->first_child, lhs,
2716 racc->offset, 0, 0, gsi,
2718 gcc_assert (*stmt == gsi_stmt (*gsi));
2719 if (TREE_CODE (lhs) == SSA_NAME)
2720 replace_uses_with_default_def_ssa_name (lhs);
2722 unlink_stmt_vdef (*stmt);
2723 gsi_remove (gsi, true);
2724 sra_stats.deleted++;
2725 return SRA_AM_REMOVED;
2727 else if (racc->first_child)
2728 generate_subtree_copies (racc->first_child, lhs,
2729 racc->offset, 0, 0, gsi, false, true);
2731 if (access_has_children_p (lacc))
2732 generate_subtree_copies (lacc->first_child, rhs, lacc->offset,
2733 0, 0, gsi, true, true);
2737 /* This gimplification must be done after generate_subtree_copies, lest we
2738 insert the subtree copies in the middle of the gimplified sequence. */
2739 if (force_gimple_rhs)
2740 rhs = force_gimple_operand_gsi (&orig_gsi, rhs, true, NULL_TREE,
2741 true, GSI_SAME_STMT);
2742 if (gimple_assign_rhs1 (*stmt) != rhs)
2744 gimple_assign_set_rhs_from_tree (&orig_gsi, rhs);
2745 gcc_assert (*stmt == gsi_stmt (orig_gsi));
2748 return modify_this_stmt ? SRA_AM_MODIFIED : SRA_AM_NONE;
2751 /* Traverse the function body and all modifications as decided in
2752 analyze_all_variable_accesses. */
2755 sra_modify_function_body (void)
2761 gimple_stmt_iterator gsi = gsi_start_bb (bb);
2762 while (!gsi_end_p (gsi))
2764 gimple stmt = gsi_stmt (gsi);
2765 enum assignment_mod_result assign_result;
2766 bool modified = false, deleted = false;
2770 switch (gimple_code (stmt))
2773 t = gimple_return_retval_ptr (stmt);
2774 if (*t != NULL_TREE)
2775 modified |= sra_modify_expr (t, &gsi, false);
2779 assign_result = sra_modify_assign (&stmt, &gsi);
2780 modified |= assign_result == SRA_AM_MODIFIED;
2781 deleted = assign_result == SRA_AM_REMOVED;
2785 /* Operands must be processed before the lhs. */
2786 for (i = 0; i < gimple_call_num_args (stmt); i++)
2788 t = gimple_call_arg_ptr (stmt, i);
2789 modified |= sra_modify_expr (t, &gsi, false);
2792 if (gimple_call_lhs (stmt))
2794 t = gimple_call_lhs_ptr (stmt);
2795 modified |= sra_modify_expr (t, &gsi, true);
2800 for (i = 0; i < gimple_asm_ninputs (stmt); i++)
2802 t = &TREE_VALUE (gimple_asm_input_op (stmt, i));
2803 modified |= sra_modify_expr (t, &gsi, false);
2805 for (i = 0; i < gimple_asm_noutputs (stmt); i++)
2807 t = &TREE_VALUE (gimple_asm_output_op (stmt, i));
2808 modified |= sra_modify_expr (t, &gsi, true);
2819 maybe_clean_eh_stmt (stmt);
2827 /* Generate statements initializing scalar replacements of parts of function
2831 initialize_parameter_reductions (void)
2833 gimple_stmt_iterator gsi;
2834 gimple_seq seq = NULL;
2837 for (parm = DECL_ARGUMENTS (current_function_decl);
2839 parm = TREE_CHAIN (parm))
2841 VEC (access_p, heap) *access_vec;
2842 struct access *access;
2844 if (!bitmap_bit_p (candidate_bitmap, DECL_UID (parm)))
2846 access_vec = get_base_access_vector (parm);
2852 seq = gimple_seq_alloc ();
2853 gsi = gsi_start (seq);
2856 for (access = VEC_index (access_p, access_vec, 0);
2858 access = access->next_grp)
2859 generate_subtree_copies (access, parm, 0, 0, 0, &gsi, true, true);
2863 gsi_insert_seq_on_edge_immediate (single_succ_edge (ENTRY_BLOCK_PTR), seq);
2866 /* The "main" function of intraprocedural SRA passes. Runs the analysis and if
2867 it reveals there are components of some aggregates to be scalarized, it runs
2868 the required transformations. */
2870 perform_intra_sra (void)
2875 if (!find_var_candidates ())
2878 if (!scan_function ())
2881 if (!analyze_all_variable_accesses ())
2884 sra_modify_function_body ();
2885 initialize_parameter_reductions ();
2887 statistics_counter_event (cfun, "Scalar replacements created",
2888 sra_stats.replacements);
2889 statistics_counter_event (cfun, "Modified expressions", sra_stats.exprs);
2890 statistics_counter_event (cfun, "Subtree copy stmts",
2891 sra_stats.subtree_copies);
2892 statistics_counter_event (cfun, "Subreplacement stmts",
2893 sra_stats.subreplacements);
2894 statistics_counter_event (cfun, "Deleted stmts", sra_stats.deleted);
2895 statistics_counter_event (cfun, "Separate LHS and RHS handling",
2896 sra_stats.separate_lhs_rhs_handling);
2898 ret = TODO_update_ssa;
2901 sra_deinitialize ();
2905 /* Perform early intraprocedural SRA. */
2907 early_intra_sra (void)
2909 sra_mode = SRA_MODE_EARLY_INTRA;
2910 return perform_intra_sra ();
2913 /* Perform "late" intraprocedural SRA. */
2915 late_intra_sra (void)
2917 sra_mode = SRA_MODE_INTRA;
2918 return perform_intra_sra ();
2923 gate_intra_sra (void)
2925 return flag_tree_sra != 0;
2929 struct gimple_opt_pass pass_sra_early =
2934 gate_intra_sra, /* gate */
2935 early_intra_sra, /* execute */
2938 0, /* static_pass_number */
2939 TV_TREE_SRA, /* tv_id */
2940 PROP_cfg | PROP_ssa, /* properties_required */
2941 0, /* properties_provided */
2942 0, /* properties_destroyed */
2943 0, /* todo_flags_start */
2947 | TODO_verify_ssa /* todo_flags_finish */
2951 struct gimple_opt_pass pass_sra =
2956 gate_intra_sra, /* gate */
2957 late_intra_sra, /* execute */
2960 0, /* static_pass_number */
2961 TV_TREE_SRA, /* tv_id */
2962 PROP_cfg | PROP_ssa, /* properties_required */
2963 0, /* properties_provided */
2964 0, /* properties_destroyed */
2965 TODO_update_address_taken, /* todo_flags_start */
2969 | TODO_verify_ssa /* todo_flags_finish */
2974 /* Return true iff PARM (which must be a parm_decl) is an unused scalar
2978 is_unused_scalar_param (tree parm)
2981 return (is_gimple_reg (parm)
2982 && (!(name = gimple_default_def (cfun, parm))
2983 || has_zero_uses (name)));
2986 /* Scan immediate uses of a default definition SSA name of a parameter PARM and
2987 examine whether there are any direct or otherwise infeasible ones. If so,
2988 return true, otherwise return false. PARM must be a gimple register with a
2989 non-NULL default definition. */
2992 ptr_parm_has_direct_uses (tree parm)
2994 imm_use_iterator ui;
2996 tree name = gimple_default_def (cfun, parm);
2999 FOR_EACH_IMM_USE_STMT (stmt, ui, name)
3002 use_operand_p use_p;
3004 if (is_gimple_debug (stmt))
3007 /* Valid uses include dereferences on the lhs and the rhs. */
3008 if (gimple_has_lhs (stmt))
3010 tree lhs = gimple_get_lhs (stmt);
3011 while (handled_component_p (lhs))
3012 lhs = TREE_OPERAND (lhs, 0);
3013 if (INDIRECT_REF_P (lhs)
3014 && TREE_OPERAND (lhs, 0) == name)
3017 if (gimple_assign_single_p (stmt))
3019 tree rhs = gimple_assign_rhs1 (stmt);
3020 while (handled_component_p (rhs))
3021 rhs = TREE_OPERAND (rhs, 0);
3022 if (INDIRECT_REF_P (rhs)
3023 && TREE_OPERAND (rhs, 0) == name)
3026 else if (is_gimple_call (stmt))
3029 for (i = 0; i < gimple_call_num_args (stmt); ++i)
3031 tree arg = gimple_call_arg (stmt, i);
3032 while (handled_component_p (arg))
3033 arg = TREE_OPERAND (arg, 0);
3034 if (INDIRECT_REF_P (arg)
3035 && TREE_OPERAND (arg, 0) == name)
3040 /* If the number of valid uses does not match the number of
3041 uses in this stmt there is an unhandled use. */
3042 FOR_EACH_IMM_USE_ON_STMT (use_p, ui)
3049 BREAK_FROM_IMM_USE_STMT (ui);
3055 /* Identify candidates for reduction for IPA-SRA based on their type and mark
3056 them in candidate_bitmap. Note that these do not necessarily include
3057 parameter which are unused and thus can be removed. Return true iff any
3058 such candidate has been found. */
3061 find_param_candidates (void)
3067 for (parm = DECL_ARGUMENTS (current_function_decl);
3069 parm = TREE_CHAIN (parm))
3071 tree type = TREE_TYPE (parm);
3075 if (TREE_THIS_VOLATILE (parm)
3076 || TREE_ADDRESSABLE (parm)
3077 || (!is_gimple_reg_type (type) && is_va_list_type (type)))
3080 if (is_unused_scalar_param (parm))
3086 if (POINTER_TYPE_P (type))
3088 type = TREE_TYPE (type);
3090 if (TREE_CODE (type) == FUNCTION_TYPE
3091 || TYPE_VOLATILE (type)
3092 || !is_gimple_reg (parm)
3093 || is_va_list_type (type)
3094 || ptr_parm_has_direct_uses (parm))
3097 else if (!AGGREGATE_TYPE_P (type))
3100 if (!COMPLETE_TYPE_P (type)
3101 || !host_integerp (TYPE_SIZE (type), 1)
3102 || tree_low_cst (TYPE_SIZE (type), 1) == 0
3103 || (AGGREGATE_TYPE_P (type)
3104 && type_internals_preclude_sra_p (type)))
3107 bitmap_set_bit (candidate_bitmap, DECL_UID (parm));
3109 if (dump_file && (dump_flags & TDF_DETAILS))
3111 fprintf (dump_file, "Candidate (%d): ", DECL_UID (parm));
3112 print_generic_expr (dump_file, parm, 0);
3113 fprintf (dump_file, "\n");
3117 func_param_count = count;
3121 /* Callback of walk_aliased_vdefs, marks the access passed as DATA as
3125 mark_maybe_modified (ao_ref *ao ATTRIBUTE_UNUSED, tree vdef ATTRIBUTE_UNUSED,
3128 struct access *repr = (struct access *) data;
3130 repr->grp_maybe_modified = 1;
3134 /* Analyze what representatives (in linked lists accessible from
3135 REPRESENTATIVES) can be modified by side effects of statements in the
3136 current function. */
3139 analyze_modified_params (VEC (access_p, heap) *representatives)
3143 for (i = 0; i < func_param_count; i++)
3145 struct access *repr;
3147 for (repr = VEC_index (access_p, representatives, i);
3149 repr = repr->next_grp)
3151 struct access *access;
3155 if (no_accesses_p (repr))
3157 if (!POINTER_TYPE_P (TREE_TYPE (repr->base))
3158 || repr->grp_maybe_modified)
3161 ao_ref_init (&ar, repr->expr);
3162 visited = BITMAP_ALLOC (NULL);
3163 for (access = repr; access; access = access->next_sibling)
3165 /* All accesses are read ones, otherwise grp_maybe_modified would
3166 be trivially set. */
3167 walk_aliased_vdefs (&ar, gimple_vuse (access->stmt),
3168 mark_maybe_modified, repr, &visited);
3169 if (repr->grp_maybe_modified)
3172 BITMAP_FREE (visited);
3177 /* Propagate distances in bb_dereferences in the opposite direction than the
3178 control flow edges, in each step storing the maximum of the current value
3179 and the minimum of all successors. These steps are repeated until the table
3180 stabilizes. Note that BBs which might terminate the functions (according to
3181 final_bbs bitmap) never updated in this way. */
3184 propagate_dereference_distances (void)
3186 VEC (basic_block, heap) *queue;
3189 queue = VEC_alloc (basic_block, heap, last_basic_block_for_function (cfun));
3190 VEC_quick_push (basic_block, queue, ENTRY_BLOCK_PTR);
3193 VEC_quick_push (basic_block, queue, bb);
3197 while (!VEC_empty (basic_block, queue))
3201 bool change = false;
3204 bb = VEC_pop (basic_block, queue);
3207 if (bitmap_bit_p (final_bbs, bb->index))
3210 for (i = 0; i < func_param_count; i++)
3212 int idx = bb->index * func_param_count + i;
3214 HOST_WIDE_INT inh = 0;
3216 FOR_EACH_EDGE (e, ei, bb->succs)
3218 int succ_idx = e->dest->index * func_param_count + i;
3220 if (e->src == EXIT_BLOCK_PTR)
3226 inh = bb_dereferences [succ_idx];
3228 else if (bb_dereferences [succ_idx] < inh)
3229 inh = bb_dereferences [succ_idx];
3232 if (!first && bb_dereferences[idx] < inh)
3234 bb_dereferences[idx] = inh;
3239 if (change && !bitmap_bit_p (final_bbs, bb->index))
3240 FOR_EACH_EDGE (e, ei, bb->preds)
3245 e->src->aux = e->src;
3246 VEC_quick_push (basic_block, queue, e->src);
3250 VEC_free (basic_block, heap, queue);
3253 /* Dump a dereferences TABLE with heading STR to file F. */
3256 dump_dereferences_table (FILE *f, const char *str, HOST_WIDE_INT *table)
3260 fprintf (dump_file, str);
3261 FOR_BB_BETWEEN (bb, ENTRY_BLOCK_PTR, EXIT_BLOCK_PTR, next_bb)
3263 fprintf (f, "%4i %i ", bb->index, bitmap_bit_p (final_bbs, bb->index));
3264 if (bb != EXIT_BLOCK_PTR)
3267 for (i = 0; i < func_param_count; i++)
3269 int idx = bb->index * func_param_count + i;
3270 fprintf (f, " %4" HOST_WIDE_INT_PRINT "d", table[idx]);
3275 fprintf (dump_file, "\n");
3278 /* Determine what (parts of) parameters passed by reference that are not
3279 assigned to are not certainly dereferenced in this function and thus the
3280 dereferencing cannot be safely moved to the caller without potentially
3281 introducing a segfault. Mark such REPRESENTATIVES as
3282 grp_not_necessarilly_dereferenced.
3284 The dereferenced maximum "distance," i.e. the offset + size of the accessed
3285 part is calculated rather than simple booleans are calculated for each
3286 pointer parameter to handle cases when only a fraction of the whole
3287 aggregate is allocated (see testsuite/gcc.c-torture/execute/ipa-sra-2.c for
3290 The maximum dereference distances for each pointer parameter and BB are
3291 already stored in bb_dereference. This routine simply propagates these
3292 values upwards by propagate_dereference_distances and then compares the
3293 distances of individual parameters in the ENTRY BB to the equivalent
3294 distances of each representative of a (fraction of a) parameter. */
3297 analyze_caller_dereference_legality (VEC (access_p, heap) *representatives)
3301 if (dump_file && (dump_flags & TDF_DETAILS))
3302 dump_dereferences_table (dump_file,
3303 "Dereference table before propagation:\n",
3306 propagate_dereference_distances ();
3308 if (dump_file && (dump_flags & TDF_DETAILS))
3309 dump_dereferences_table (dump_file,
3310 "Dereference table after propagation:\n",
3313 for (i = 0; i < func_param_count; i++)
3315 struct access *repr = VEC_index (access_p, representatives, i);
3316 int idx = ENTRY_BLOCK_PTR->index * func_param_count + i;
3318 if (!repr || no_accesses_p (repr))
3323 if ((repr->offset + repr->size) > bb_dereferences[idx])
3324 repr->grp_not_necessarilly_dereferenced = 1;
3325 repr = repr->next_grp;
3331 /* Return the representative access for the parameter declaration PARM if it is
3332 a scalar passed by reference which is not written to and the pointer value
3333 is not used directly. Thus, if it is legal to dereference it in the caller
3334 and we can rule out modifications through aliases, such parameter should be
3335 turned into one passed by value. Return NULL otherwise. */
3337 static struct access *
3338 unmodified_by_ref_scalar_representative (tree parm)
3340 int i, access_count;
3341 struct access *repr;
3342 VEC (access_p, heap) *access_vec;
3344 access_vec = get_base_access_vector (parm);
3345 gcc_assert (access_vec);
3346 repr = VEC_index (access_p, access_vec, 0);
3349 repr->group_representative = repr;
3351 access_count = VEC_length (access_p, access_vec);
3352 for (i = 1; i < access_count; i++)
3354 struct access *access = VEC_index (access_p, access_vec, i);
3357 access->group_representative = repr;
3358 access->next_sibling = repr->next_sibling;
3359 repr->next_sibling = access;
3363 repr->grp_scalar_ptr = 1;
3367 /* Return true iff this access precludes IPA-SRA of the parameter it is
3371 access_precludes_ipa_sra_p (struct access *access)
3373 /* Avoid issues such as the second simple testcase in PR 42025. The problem
3374 is incompatible assign in a call statement (and possibly even in asm
3375 statements). This can be relaxed by using a new temporary but only for
3376 non-TREE_ADDRESSABLE types and is probably not worth the complexity. (In
3377 intraprocedural SRA we deal with this by keeping the old aggregate around,
3378 something we cannot do in IPA-SRA.) */
3380 && (is_gimple_call (access->stmt)
3381 || gimple_code (access->stmt) == GIMPLE_ASM))
3388 /* Sort collected accesses for parameter PARM, identify representatives for
3389 each accessed region and link them together. Return NULL if there are
3390 different but overlapping accesses, return the special ptr value meaning
3391 there are no accesses for this parameter if that is the case and return the
3392 first representative otherwise. Set *RO_GRP if there is a group of accesses
3393 with only read (i.e. no write) accesses. */
3395 static struct access *
3396 splice_param_accesses (tree parm, bool *ro_grp)
3398 int i, j, access_count, group_count;
3399 int agg_size, total_size = 0;
3400 struct access *access, *res, **prev_acc_ptr = &res;
3401 VEC (access_p, heap) *access_vec;
3403 access_vec = get_base_access_vector (parm);
3405 return &no_accesses_representant;
3406 access_count = VEC_length (access_p, access_vec);
3408 qsort (VEC_address (access_p, access_vec), access_count, sizeof (access_p),
3409 compare_access_positions);
3414 while (i < access_count)
3417 access = VEC_index (access_p, access_vec, i);
3418 modification = access->write;
3419 if (access_precludes_ipa_sra_p (access))
3422 /* Access is about to become group representative unless we find some
3423 nasty overlap which would preclude us from breaking this parameter
3427 while (j < access_count)
3429 struct access *ac2 = VEC_index (access_p, access_vec, j);
3430 if (ac2->offset != access->offset)
3432 /* All or nothing law for parameters. */
3433 if (access->offset + access->size > ac2->offset)
3438 else if (ac2->size != access->size)
3441 if (access_precludes_ipa_sra_p (ac2))
3444 modification |= ac2->write;
3445 ac2->group_representative = access;
3446 ac2->next_sibling = access->next_sibling;
3447 access->next_sibling = ac2;
3452 access->grp_maybe_modified = modification;
3455 *prev_acc_ptr = access;
3456 prev_acc_ptr = &access->next_grp;
3457 total_size += access->size;
3461 if (POINTER_TYPE_P (TREE_TYPE (parm)))
3462 agg_size = tree_low_cst (TYPE_SIZE (TREE_TYPE (TREE_TYPE (parm))), 1);
3464 agg_size = tree_low_cst (TYPE_SIZE (TREE_TYPE (parm)), 1);
3465 if (total_size >= agg_size)
3468 gcc_assert (group_count > 0);
3472 /* Decide whether parameters with representative accesses given by REPR should
3473 be reduced into components. */
3476 decide_one_param_reduction (struct access *repr)
3478 int total_size, cur_parm_size, agg_size, new_param_count, parm_size_limit;
3483 cur_parm_size = tree_low_cst (TYPE_SIZE (TREE_TYPE (parm)), 1);
3484 gcc_assert (cur_parm_size > 0);
3486 if (POINTER_TYPE_P (TREE_TYPE (parm)))
3489 agg_size = tree_low_cst (TYPE_SIZE (TREE_TYPE (TREE_TYPE (parm))), 1);
3494 agg_size = cur_parm_size;
3500 fprintf (dump_file, "Evaluating PARAM group sizes for ");
3501 print_generic_expr (dump_file, parm, 0);
3502 fprintf (dump_file, " (UID: %u): \n", DECL_UID (parm));
3503 for (acc = repr; acc; acc = acc->next_grp)
3504 dump_access (dump_file, acc, true);
3508 new_param_count = 0;
3510 for (; repr; repr = repr->next_grp)
3512 gcc_assert (parm == repr->base);
3515 if (!by_ref || (!repr->grp_maybe_modified
3516 && !repr->grp_not_necessarilly_dereferenced))
3517 total_size += repr->size;
3519 total_size += cur_parm_size;
3522 gcc_assert (new_param_count > 0);
3524 if (optimize_function_for_size_p (cfun))
3525 parm_size_limit = cur_parm_size;
3527 parm_size_limit = (PARAM_VALUE (PARAM_IPA_SRA_PTR_GROWTH_FACTOR)
3530 if (total_size < agg_size
3531 && total_size <= parm_size_limit)
3534 fprintf (dump_file, " ....will be split into %i components\n",
3536 return new_param_count;
3542 /* The order of the following enums is important, we need to do extra work for
3543 UNUSED_PARAMS, BY_VAL_ACCESSES and UNMODIF_BY_REF_ACCESSES. */
3544 enum ipa_splicing_result { NO_GOOD_ACCESS, UNUSED_PARAMS, BY_VAL_ACCESSES,
3545 MODIF_BY_REF_ACCESSES, UNMODIF_BY_REF_ACCESSES };
3547 /* Identify representatives of all accesses to all candidate parameters for
3548 IPA-SRA. Return result based on what representatives have been found. */
3550 static enum ipa_splicing_result
3551 splice_all_param_accesses (VEC (access_p, heap) **representatives)
3553 enum ipa_splicing_result result = NO_GOOD_ACCESS;
3555 struct access *repr;
3557 *representatives = VEC_alloc (access_p, heap, func_param_count);
3559 for (parm = DECL_ARGUMENTS (current_function_decl);
3561 parm = TREE_CHAIN (parm))
3563 if (is_unused_scalar_param (parm))
3565 VEC_quick_push (access_p, *representatives,
3566 &no_accesses_representant);
3567 if (result == NO_GOOD_ACCESS)
3568 result = UNUSED_PARAMS;
3570 else if (POINTER_TYPE_P (TREE_TYPE (parm))
3571 && is_gimple_reg_type (TREE_TYPE (TREE_TYPE (parm)))
3572 && bitmap_bit_p (candidate_bitmap, DECL_UID (parm)))
3574 repr = unmodified_by_ref_scalar_representative (parm);
3575 VEC_quick_push (access_p, *representatives, repr);
3577 result = UNMODIF_BY_REF_ACCESSES;
3579 else if (bitmap_bit_p (candidate_bitmap, DECL_UID (parm)))
3581 bool ro_grp = false;
3582 repr = splice_param_accesses (parm, &ro_grp);
3583 VEC_quick_push (access_p, *representatives, repr);
3585 if (repr && !no_accesses_p (repr))
3587 if (POINTER_TYPE_P (TREE_TYPE (parm)))
3590 result = UNMODIF_BY_REF_ACCESSES;
3591 else if (result < MODIF_BY_REF_ACCESSES)
3592 result = MODIF_BY_REF_ACCESSES;
3594 else if (result < BY_VAL_ACCESSES)
3595 result = BY_VAL_ACCESSES;
3597 else if (no_accesses_p (repr) && (result == NO_GOOD_ACCESS))
3598 result = UNUSED_PARAMS;
3601 VEC_quick_push (access_p, *representatives, NULL);
3604 if (result == NO_GOOD_ACCESS)
3606 VEC_free (access_p, heap, *representatives);
3607 *representatives = NULL;
3608 return NO_GOOD_ACCESS;
3614 /* Return the index of BASE in PARMS. Abort if it is not found. */
3617 get_param_index (tree base, VEC(tree, heap) *parms)
3621 len = VEC_length (tree, parms);
3622 for (i = 0; i < len; i++)
3623 if (VEC_index (tree, parms, i) == base)
3628 /* Convert the decisions made at the representative level into compact
3629 parameter adjustments. REPRESENTATIVES are pointers to first
3630 representatives of each param accesses, ADJUSTMENTS_COUNT is the expected
3631 final number of adjustments. */
3633 static ipa_parm_adjustment_vec
3634 turn_representatives_into_adjustments (VEC (access_p, heap) *representatives,
3635 int adjustments_count)
3637 VEC (tree, heap) *parms;
3638 ipa_parm_adjustment_vec adjustments;
3642 gcc_assert (adjustments_count > 0);
3643 parms = ipa_get_vector_of_formal_parms (current_function_decl);
3644 adjustments = VEC_alloc (ipa_parm_adjustment_t, heap, adjustments_count);
3645 parm = DECL_ARGUMENTS (current_function_decl);
3646 for (i = 0; i < func_param_count; i++, parm = TREE_CHAIN (parm))
3648 struct access *repr = VEC_index (access_p, representatives, i);
3650 if (!repr || no_accesses_p (repr))
3652 struct ipa_parm_adjustment *adj;
3654 adj = VEC_quick_push (ipa_parm_adjustment_t, adjustments, NULL);
3655 memset (adj, 0, sizeof (*adj));
3656 adj->base_index = get_param_index (parm, parms);
3659 adj->copy_param = 1;
3661 adj->remove_param = 1;
3665 struct ipa_parm_adjustment *adj;
3666 int index = get_param_index (parm, parms);
3668 for (; repr; repr = repr->next_grp)
3670 adj = VEC_quick_push (ipa_parm_adjustment_t, adjustments, NULL);
3671 memset (adj, 0, sizeof (*adj));
3672 gcc_assert (repr->base == parm);
3673 adj->base_index = index;
3674 adj->base = repr->base;
3675 adj->type = repr->type;
3676 adj->offset = repr->offset;
3677 adj->by_ref = (POINTER_TYPE_P (TREE_TYPE (repr->base))
3678 && (repr->grp_maybe_modified
3679 || repr->grp_not_necessarilly_dereferenced));
3684 VEC_free (tree, heap, parms);
3688 /* Analyze the collected accesses and produce a plan what to do with the
3689 parameters in the form of adjustments, NULL meaning nothing. */
3691 static ipa_parm_adjustment_vec
3692 analyze_all_param_acesses (void)
3694 enum ipa_splicing_result repr_state;
3695 bool proceed = false;
3696 int i, adjustments_count = 0;
3697 VEC (access_p, heap) *representatives;
3698 ipa_parm_adjustment_vec adjustments;
3700 repr_state = splice_all_param_accesses (&representatives);
3701 if (repr_state == NO_GOOD_ACCESS)
3704 /* If there are any parameters passed by reference which are not modified
3705 directly, we need to check whether they can be modified indirectly. */
3706 if (repr_state == UNMODIF_BY_REF_ACCESSES)
3708 analyze_caller_dereference_legality (representatives);
3709 analyze_modified_params (representatives);
3712 for (i = 0; i < func_param_count; i++)
3714 struct access *repr = VEC_index (access_p, representatives, i);
3716 if (repr && !no_accesses_p (repr))
3718 if (repr->grp_scalar_ptr)
3720 adjustments_count++;
3721 if (repr->grp_not_necessarilly_dereferenced
3722 || repr->grp_maybe_modified)
3723 VEC_replace (access_p, representatives, i, NULL);
3727 sra_stats.scalar_by_ref_to_by_val++;
3732 int new_components = decide_one_param_reduction (repr);
3734 if (new_components == 0)
3736 VEC_replace (access_p, representatives, i, NULL);
3737 adjustments_count++;
3741 adjustments_count += new_components;
3742 sra_stats.aggregate_params_reduced++;
3743 sra_stats.param_reductions_created += new_components;
3750 if (no_accesses_p (repr))
3753 sra_stats.deleted_unused_parameters++;
3755 adjustments_count++;
3759 if (!proceed && dump_file)
3760 fprintf (dump_file, "NOT proceeding to change params.\n");
3763 adjustments = turn_representatives_into_adjustments (representatives,
3768 VEC_free (access_p, heap, representatives);
3772 /* If a parameter replacement identified by ADJ does not yet exist in the form
3773 of declaration, create it and record it, otherwise return the previously
3777 get_replaced_param_substitute (struct ipa_parm_adjustment *adj)
3780 if (!adj->new_ssa_base)
3782 char *pretty_name = make_fancy_name (adj->base);
3784 repl = create_tmp_reg (TREE_TYPE (adj->base), "ISR");
3785 DECL_NAME (repl) = get_identifier (pretty_name);
3786 obstack_free (&name_obstack, pretty_name);
3789 add_referenced_var (repl);
3790 adj->new_ssa_base = repl;
3793 repl = adj->new_ssa_base;
3797 /* Find the first adjustment for a particular parameter BASE in a vector of
3798 ADJUSTMENTS which is not a copy_param. Return NULL if there is no such
3801 static struct ipa_parm_adjustment *
3802 get_adjustment_for_base (ipa_parm_adjustment_vec adjustments, tree base)
3806 len = VEC_length (ipa_parm_adjustment_t, adjustments);
3807 for (i = 0; i < len; i++)
3809 struct ipa_parm_adjustment *adj;
3811 adj = VEC_index (ipa_parm_adjustment_t, adjustments, i);
3812 if (!adj->copy_param && adj->base == base)
3819 /* If the statement STMT defines an SSA_NAME of a parameter which is to be
3820 removed because its value is not used, replace the SSA_NAME with a one
3821 relating to a created VAR_DECL together all of its uses and return true.
3822 ADJUSTMENTS is a pointer to an adjustments vector. */
3825 replace_removed_params_ssa_names (gimple stmt,
3826 ipa_parm_adjustment_vec adjustments)
3828 struct ipa_parm_adjustment *adj;
3829 tree lhs, decl, repl, name;
3831 if (gimple_code (stmt) == GIMPLE_PHI)
3832 lhs = gimple_phi_result (stmt);
3833 else if (is_gimple_assign (stmt))
3834 lhs = gimple_assign_lhs (stmt);
3835 else if (is_gimple_call (stmt))
3836 lhs = gimple_call_lhs (stmt);
3840 if (TREE_CODE (lhs) != SSA_NAME)
3842 decl = SSA_NAME_VAR (lhs);
3843 if (TREE_CODE (decl) != PARM_DECL)
3846 adj = get_adjustment_for_base (adjustments, decl);
3850 repl = get_replaced_param_substitute (adj);
3851 name = make_ssa_name (repl, stmt);
3855 fprintf (dump_file, "replacing an SSA name of a removed param ");
3856 print_generic_expr (dump_file, lhs, 0);
3857 fprintf (dump_file, " with ");
3858 print_generic_expr (dump_file, name, 0);
3859 fprintf (dump_file, "\n");
3862 if (is_gimple_assign (stmt))
3863 gimple_assign_set_lhs (stmt, name);
3864 else if (is_gimple_call (stmt))
3865 gimple_call_set_lhs (stmt, name);
3867 gimple_phi_set_result (stmt, name);
3869 replace_uses_by (lhs, name);
3873 /* If the expression *EXPR should be replaced by a reduction of a parameter, do
3874 so. ADJUSTMENTS is a pointer to a vector of adjustments. CONVERT
3875 specifies whether the function should care about type incompatibility the
3876 current and new expressions. If it is false, the function will leave
3877 incompatibility issues to the caller. Return true iff the expression
3881 sra_ipa_modify_expr (tree *expr, bool convert,
3882 ipa_parm_adjustment_vec adjustments)
3885 struct ipa_parm_adjustment *adj, *cand = NULL;
3886 HOST_WIDE_INT offset, size, max_size;
3889 len = VEC_length (ipa_parm_adjustment_t, adjustments);
3891 if (TREE_CODE (*expr) == BIT_FIELD_REF
3892 || TREE_CODE (*expr) == IMAGPART_EXPR
3893 || TREE_CODE (*expr) == REALPART_EXPR)
3895 expr = &TREE_OPERAND (*expr, 0);
3899 base = get_ref_base_and_extent (*expr, &offset, &size, &max_size);
3900 if (!base || size == -1 || max_size == -1)
3903 if (INDIRECT_REF_P (base))
3904 base = TREE_OPERAND (base, 0);
3906 base = get_ssa_base_param (base);
3907 if (!base || TREE_CODE (base) != PARM_DECL)
3910 for (i = 0; i < len; i++)
3912 adj = VEC_index (ipa_parm_adjustment_t, adjustments, i);
3914 if (adj->base == base &&
3915 (adj->offset == offset || adj->remove_param))
3921 if (!cand || cand->copy_param || cand->remove_param)
3927 src = build1 (INDIRECT_REF, TREE_TYPE (TREE_TYPE (cand->reduction)),
3929 folded = gimple_fold_indirect_ref (src);
3934 src = cand->reduction;
3936 if (dump_file && (dump_flags & TDF_DETAILS))
3938 fprintf (dump_file, "About to replace expr ");
3939 print_generic_expr (dump_file, *expr, 0);
3940 fprintf (dump_file, " with ");
3941 print_generic_expr (dump_file, src, 0);
3942 fprintf (dump_file, "\n");
3945 if (convert && !useless_type_conversion_p (TREE_TYPE (*expr), cand->type))
3947 tree vce = build1 (VIEW_CONVERT_EXPR, TREE_TYPE (*expr), src);
3955 /* If the statement pointed to by STMT_PTR contains any expressions that need
3956 to replaced with a different one as noted by ADJUSTMENTS, do so. Handle any
3957 potential type incompatibilities (GSI is used to accommodate conversion
3958 statements and must point to the statement). Return true iff the statement
3962 sra_ipa_modify_assign (gimple *stmt_ptr, gimple_stmt_iterator *gsi,
3963 ipa_parm_adjustment_vec adjustments)
3965 gimple stmt = *stmt_ptr;
3966 tree *lhs_p, *rhs_p;
3969 if (!gimple_assign_single_p (stmt))
3972 rhs_p = gimple_assign_rhs1_ptr (stmt);
3973 lhs_p = gimple_assign_lhs_ptr (stmt);
3975 any = sra_ipa_modify_expr (rhs_p, false, adjustments);
3976 any |= sra_ipa_modify_expr (lhs_p, false, adjustments);
3979 tree new_rhs = NULL_TREE;
3981 if (!useless_type_conversion_p (TREE_TYPE (*lhs_p), TREE_TYPE (*rhs_p)))
3983 if (TREE_CODE (*rhs_p) == CONSTRUCTOR)
3985 /* V_C_Es of constructors can cause trouble (PR 42714). */
3986 if (is_gimple_reg_type (TREE_TYPE (*lhs_p)))
3987 *rhs_p = fold_convert (TREE_TYPE (*lhs_p), integer_zero_node);
3989 *rhs_p = build_constructor (TREE_TYPE (*lhs_p), 0);
3992 new_rhs = fold_build1_loc (gimple_location (stmt),
3993 VIEW_CONVERT_EXPR, TREE_TYPE (*lhs_p),
3996 else if (REFERENCE_CLASS_P (*rhs_p)
3997 && is_gimple_reg_type (TREE_TYPE (*lhs_p))
3998 && !is_gimple_reg (*lhs_p))
3999 /* This can happen when an assignment in between two single field
4000 structures is turned into an assignment in between two pointers to
4001 scalars (PR 42237). */
4006 tree tmp = force_gimple_operand_gsi (gsi, new_rhs, true, NULL_TREE,
4007 true, GSI_SAME_STMT);
4009 gimple_assign_set_rhs_from_tree (gsi, tmp);
4018 /* Traverse the function body and all modifications as described in
4022 ipa_sra_modify_function_body (ipa_parm_adjustment_vec adjustments)
4028 gimple_stmt_iterator gsi;
4029 bool bb_changed = false;
4031 for (gsi = gsi_start_phis (bb); !gsi_end_p (gsi); gsi_next (&gsi))
4032 replace_removed_params_ssa_names (gsi_stmt (gsi), adjustments);
4034 gsi = gsi_start_bb (bb);
4035 while (!gsi_end_p (gsi))
4037 gimple stmt = gsi_stmt (gsi);
4038 bool modified = false;
4042 switch (gimple_code (stmt))
4045 t = gimple_return_retval_ptr (stmt);
4046 if (*t != NULL_TREE)
4047 modified |= sra_ipa_modify_expr (t, true, adjustments);
4051 modified |= sra_ipa_modify_assign (&stmt, &gsi, adjustments);
4052 modified |= replace_removed_params_ssa_names (stmt, adjustments);
4056 /* Operands must be processed before the lhs. */
4057 for (i = 0; i < gimple_call_num_args (stmt); i++)
4059 t = gimple_call_arg_ptr (stmt, i);
4060 modified |= sra_ipa_modify_expr (t, true, adjustments);
4063 if (gimple_call_lhs (stmt))
4065 t = gimple_call_lhs_ptr (stmt);
4066 modified |= sra_ipa_modify_expr (t, false, adjustments);
4067 modified |= replace_removed_params_ssa_names (stmt,
4073 for (i = 0; i < gimple_asm_ninputs (stmt); i++)
4075 t = &TREE_VALUE (gimple_asm_input_op (stmt, i));
4076 modified |= sra_ipa_modify_expr (t, true, adjustments);
4078 for (i = 0; i < gimple_asm_noutputs (stmt); i++)
4080 t = &TREE_VALUE (gimple_asm_output_op (stmt, i));
4081 modified |= sra_ipa_modify_expr (t, false, adjustments);
4093 maybe_clean_eh_stmt (stmt);
4098 gimple_purge_dead_eh_edges (bb);
4102 /* Call gimple_debug_bind_reset_value on all debug statements describing
4103 gimple register parameters that are being removed or replaced. */
4106 sra_ipa_reset_debug_stmts (ipa_parm_adjustment_vec adjustments)
4110 len = VEC_length (ipa_parm_adjustment_t, adjustments);
4111 for (i = 0; i < len; i++)
4113 struct ipa_parm_adjustment *adj;
4114 imm_use_iterator ui;
4118 adj = VEC_index (ipa_parm_adjustment_t, adjustments, i);
4119 if (adj->copy_param || !is_gimple_reg (adj->base))
4121 name = gimple_default_def (cfun, adj->base);
4124 FOR_EACH_IMM_USE_STMT (stmt, ui, name)
4126 /* All other users must have been removed by
4127 ipa_sra_modify_function_body. */
4128 gcc_assert (is_gimple_debug (stmt));
4129 gimple_debug_bind_reset_value (stmt);
4135 /* Return true iff all callers have at least as many actual arguments as there
4136 are formal parameters in the current function. */
4139 all_callers_have_enough_arguments_p (struct cgraph_node *node)
4141 struct cgraph_edge *cs;
4142 for (cs = node->callers; cs; cs = cs->next_caller)
4143 if (!callsite_has_enough_arguments_p (cs->call_stmt))
4150 /* Convert all callers of NODE to pass parameters as given in ADJUSTMENTS. */
4153 convert_callers (struct cgraph_node *node, ipa_parm_adjustment_vec adjustments)
4155 tree old_cur_fndecl = current_function_decl;
4156 struct cgraph_edge *cs;
4157 basic_block this_block;
4158 bitmap recomputed_callers = BITMAP_ALLOC (NULL);
4160 for (cs = node->callers; cs; cs = cs->next_caller)
4162 current_function_decl = cs->caller->decl;
4163 push_cfun (DECL_STRUCT_FUNCTION (cs->caller->decl));
4166 fprintf (dump_file, "Adjusting call (%i -> %i) %s -> %s\n",
4167 cs->caller->uid, cs->callee->uid,
4168 cgraph_node_name (cs->caller),
4169 cgraph_node_name (cs->callee));
4171 ipa_modify_call_arguments (cs, cs->call_stmt, adjustments);
4176 for (cs = node->callers; cs; cs = cs->next_caller)
4177 if (!bitmap_bit_p (recomputed_callers, cs->caller->uid))
4179 compute_inline_parameters (cs->caller);
4180 bitmap_set_bit (recomputed_callers, cs->caller->uid);
4182 BITMAP_FREE (recomputed_callers);
4184 current_function_decl = old_cur_fndecl;
4186 if (!encountered_recursive_call)
4189 FOR_EACH_BB (this_block)
4191 gimple_stmt_iterator gsi;
4193 for (gsi = gsi_start_bb (this_block); !gsi_end_p (gsi); gsi_next (&gsi))
4195 gimple stmt = gsi_stmt (gsi);
4197 if (gimple_code (stmt) != GIMPLE_CALL)
4199 call_fndecl = gimple_call_fndecl (stmt);
4200 if (call_fndecl && cgraph_get_node (call_fndecl) == node)
4203 fprintf (dump_file, "Adjusting recursive call");
4204 ipa_modify_call_arguments (NULL, stmt, adjustments);
4212 /* Create an abstract origin declaration for OLD_DECL and make it an abstract
4213 origin of the provided decl so that there are preserved parameters for debug
4217 create_abstract_origin (tree old_decl)
4219 if (!DECL_ABSTRACT_ORIGIN (old_decl))
4221 tree new_decl = copy_node (old_decl);
4223 DECL_ABSTRACT (new_decl) = 1;
4224 SET_DECL_ASSEMBLER_NAME (new_decl, NULL_TREE);
4225 SET_DECL_RTL (new_decl, NULL);
4226 DECL_STRUCT_FUNCTION (new_decl) = NULL;
4227 DECL_ARTIFICIAL (old_decl) = 1;
4228 DECL_ABSTRACT_ORIGIN (old_decl) = new_decl;
4232 /* Perform all the modification required in IPA-SRA for NODE to have parameters
4233 as given in ADJUSTMENTS. */
4236 modify_function (struct cgraph_node *node, ipa_parm_adjustment_vec adjustments)
4238 struct cgraph_node *alias;
4239 for (alias = node->same_body; alias; alias = alias->next)
4240 ipa_modify_formal_parameters (alias->decl, adjustments, "ISRA");
4241 /* current_function_decl must be handled last, after same_body aliases,
4242 as following functions will use what it computed. */
4243 create_abstract_origin (current_function_decl);
4244 ipa_modify_formal_parameters (current_function_decl, adjustments, "ISRA");
4245 ipa_sra_modify_function_body (adjustments);
4246 sra_ipa_reset_debug_stmts (adjustments);
4247 convert_callers (node, adjustments);
4248 cgraph_make_node_local (node);
4252 /* Return false the function is apparently unsuitable for IPA-SRA based on it's
4253 attributes, return true otherwise. NODE is the cgraph node of the current
4257 ipa_sra_preliminary_function_checks (struct cgraph_node *node)
4259 if (!cgraph_node_can_be_local_p (node))
4262 fprintf (dump_file, "Function not local to this compilation unit.\n");
4266 if (DECL_VIRTUAL_P (current_function_decl))
4269 fprintf (dump_file, "Function is a virtual method.\n");
4273 if ((DECL_COMDAT (node->decl) || DECL_EXTERNAL (node->decl))
4274 && node->global.size >= MAX_INLINE_INSNS_AUTO)
4277 fprintf (dump_file, "Function too big to be made truly local.\n");
4285 "Function has no callers in this compilation unit.\n");
4292 fprintf (dump_file, "Function uses stdarg. \n");
4296 if (TYPE_ATTRIBUTES (TREE_TYPE (node->decl)))
4302 /* Perform early interprocedural SRA. */
4305 ipa_early_sra (void)
4307 struct cgraph_node *node = cgraph_node (current_function_decl);
4308 ipa_parm_adjustment_vec adjustments;
4311 if (!ipa_sra_preliminary_function_checks (node))
4315 sra_mode = SRA_MODE_EARLY_IPA;
4317 if (!find_param_candidates ())
4320 fprintf (dump_file, "Function has no IPA-SRA candidates.\n");
4324 if (!all_callers_have_enough_arguments_p (node))
4327 fprintf (dump_file, "There are callers with insufficient number of "
4332 bb_dereferences = XCNEWVEC (HOST_WIDE_INT,
4334 * last_basic_block_for_function (cfun));
4335 final_bbs = BITMAP_ALLOC (NULL);
4338 if (encountered_apply_args)
4341 fprintf (dump_file, "Function calls __builtin_apply_args().\n");
4345 if (encountered_unchangable_recursive_call)
4348 fprintf (dump_file, "Function calls itself with insufficient "
4349 "number of arguments.\n");
4353 adjustments = analyze_all_param_acesses ();
4357 ipa_dump_param_adjustments (dump_file, adjustments, current_function_decl);
4359 modify_function (node, adjustments);
4360 VEC_free (ipa_parm_adjustment_t, heap, adjustments);
4361 ret = TODO_update_ssa;
4363 statistics_counter_event (cfun, "Unused parameters deleted",
4364 sra_stats.deleted_unused_parameters);
4365 statistics_counter_event (cfun, "Scalar parameters converted to by-value",
4366 sra_stats.scalar_by_ref_to_by_val);
4367 statistics_counter_event (cfun, "Aggregate parameters broken up",
4368 sra_stats.aggregate_params_reduced);
4369 statistics_counter_event (cfun, "Aggregate parameter components created",
4370 sra_stats.param_reductions_created);
4373 BITMAP_FREE (final_bbs);
4374 free (bb_dereferences);
4376 sra_deinitialize ();
4380 /* Return if early ipa sra shall be performed. */
4382 ipa_early_sra_gate (void)
4384 return flag_ipa_sra;
4387 struct gimple_opt_pass pass_early_ipa_sra =
4391 "eipa_sra", /* name */
4392 ipa_early_sra_gate, /* gate */
4393 ipa_early_sra, /* execute */
4396 0, /* static_pass_number */
4397 TV_IPA_SRA, /* tv_id */
4398 0, /* properties_required */
4399 0, /* properties_provided */
4400 0, /* properties_destroyed */
4401 0, /* todo_flags_start */
4402 TODO_dump_func | TODO_dump_cgraph /* todo_flags_finish */