1 /* Function splitting pass
2 Copyright (C) 2010, 2011
3 Free Software Foundation, Inc.
4 Contributed by Jan Hubicka <jh@suse.cz>
6 This file is part of GCC.
8 GCC is free software; you can redistribute it and/or modify it under
9 the terms of the GNU General Public License as published by the Free
10 Software Foundation; either version 3, or (at your option) any later
13 GCC is distributed in the hope that it will be useful, but WITHOUT ANY
14 WARRANTY; without even the implied warranty of MERCHANTABILITY or
15 FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
18 You should have received a copy of the GNU General Public License
19 along with GCC; see the file COPYING3. If not see
20 <http://www.gnu.org/licenses/>. */
22 /* The purpose of this pass is to split function bodies to improve
23 inlining. I.e. for function of the form:
48 When func becomes inlinable and when cheap_test is often true, inlining func,
49 but not fund.part leads to performance improvement similar as inlining
50 original func while the code size growth is smaller.
52 The pass is organized in three stages:
53 1) Collect local info about basic block into BB_INFO structure and
54 compute function body estimated size and time.
55 2) Via DFS walk find all possible basic blocks where we can split
57 3) If split point is found, split at the specified BB by creating a clone
58 and updating function to call it.
60 The decisions what functions to split are in execute_split_functions
63 There are several possible future improvements for this pass including:
65 1) Splitting to break up large functions
66 2) Splitting to reduce stack frame usage
67 3) Allow split part of function to use values computed in the header part.
68 The values needs to be passed to split function, perhaps via same
69 interface as for nested functions or as argument.
70 4) Support for simple rematerialization. I.e. when split part use
71 value computed in header from function parameter in very cheap way, we
72 can just recompute it.
73 5) Support splitting of nested functions.
74 6) Support non-SSA arguments.
75 7) There is nothing preventing us from producing multiple parts of single function
76 when needed or splitting also the parts. */
80 #include "coretypes.h"
85 #include "tree-flow.h"
86 #include "tree-pass.h"
89 #include "diagnostic.h"
90 #include "tree-dump.h"
91 #include "tree-inline.h"
94 #include "gimple-pretty-print.h"
96 /* Per basic block info. */
104 DEF_VEC_ALLOC_O(bb_info,heap);
106 static VEC(bb_info, heap) *bb_info_vec;
108 /* Description of split point. */
112 /* Size of the partitions. */
113 unsigned int header_time, header_size, split_time, split_size;
115 /* SSA names that need to be passed into spit function. */
116 bitmap ssa_names_to_pass;
118 /* Basic block where we split (that will become entry point of new function. */
119 basic_block entry_bb;
121 /* Basic blocks we are splitting away. */
124 /* True when return value is computed on split part and thus it needs
126 bool split_part_set_retval;
129 /* Best split point found. */
131 struct split_point best_split_point;
133 /* Set of basic blocks that are not allowed to dominate a split point. */
135 static bitmap forbidden_dominators;
137 static tree find_retval (basic_block return_bb);
139 /* Callback for walk_stmt_load_store_addr_ops. If T is non-SSA automatic
140 variable, check it if it is present in bitmap passed via DATA. */
143 test_nonssa_use (gimple stmt ATTRIBUTE_UNUSED, tree t, void *data)
145 t = get_base_address (t);
147 if (!t || is_gimple_reg (t))
150 if (TREE_CODE (t) == PARM_DECL
151 || (TREE_CODE (t) == VAR_DECL
152 && auto_var_in_fn_p (t, current_function_decl))
153 || TREE_CODE (t) == RESULT_DECL
154 || TREE_CODE (t) == LABEL_DECL)
155 return bitmap_bit_p ((bitmap)data, DECL_UID (t));
157 /* For DECL_BY_REFERENCE, the return value is actually a pointer. We want
158 to pretend that the value pointed to is actual result decl. */
159 if ((TREE_CODE (t) == MEM_REF || INDIRECT_REF_P (t))
160 && TREE_CODE (TREE_OPERAND (t, 0)) == SSA_NAME
161 && TREE_CODE (SSA_NAME_VAR (TREE_OPERAND (t, 0))) == RESULT_DECL
162 && DECL_BY_REFERENCE (DECL_RESULT (current_function_decl)))
164 bitmap_bit_p ((bitmap)data,
165 DECL_UID (DECL_RESULT (current_function_decl)));
170 /* Dump split point CURRENT. */
173 dump_split_point (FILE * file, struct split_point *current)
176 "Split point at BB %i header time:%i header size: %i"
177 " split time: %i split size: %i\n bbs: ",
178 current->entry_bb->index, current->header_time,
179 current->header_size, current->split_time, current->split_size);
180 dump_bitmap (file, current->split_bbs);
181 fprintf (file, " SSA names to pass: ");
182 dump_bitmap (file, current->ssa_names_to_pass);
185 /* Look for all BBs in header that might lead to the split part and verify
186 that they are not defining any non-SSA var used by the split part.
187 Parameters are the same as for consider_split. */
190 verify_non_ssa_vars (struct split_point *current, bitmap non_ssa_vars,
191 basic_block return_bb)
193 bitmap seen = BITMAP_ALLOC (NULL);
194 VEC (basic_block,heap) *worklist = NULL;
199 FOR_EACH_EDGE (e, ei, current->entry_bb->preds)
200 if (e->src != ENTRY_BLOCK_PTR
201 && !bitmap_bit_p (current->split_bbs, e->src->index))
203 VEC_safe_push (basic_block, heap, worklist, e->src);
204 bitmap_set_bit (seen, e->src->index);
207 while (!VEC_empty (basic_block, worklist))
209 gimple_stmt_iterator bsi;
210 basic_block bb = VEC_pop (basic_block, worklist);
212 FOR_EACH_EDGE (e, ei, bb->preds)
213 if (e->src != ENTRY_BLOCK_PTR
214 && bitmap_set_bit (seen, e->src->index))
216 gcc_checking_assert (!bitmap_bit_p (current->split_bbs,
218 VEC_safe_push (basic_block, heap, worklist, e->src);
220 for (bsi = gsi_start_bb (bb); !gsi_end_p (bsi); gsi_next (&bsi))
222 gimple stmt = gsi_stmt (bsi);
223 if (is_gimple_debug (stmt))
225 if (walk_stmt_load_store_addr_ops
226 (stmt, non_ssa_vars, test_nonssa_use, test_nonssa_use,
232 if (gimple_code (stmt) == GIMPLE_LABEL
233 && test_nonssa_use (stmt, gimple_label_label (stmt),
240 for (bsi = gsi_start_phis (bb); !gsi_end_p (bsi); gsi_next (&bsi))
242 if (walk_stmt_load_store_addr_ops
243 (gsi_stmt (bsi), non_ssa_vars, test_nonssa_use, test_nonssa_use,
250 FOR_EACH_EDGE (e, ei, bb->succs)
252 if (e->dest != return_bb)
254 for (bsi = gsi_start_phis (return_bb); !gsi_end_p (bsi);
257 gimple stmt = gsi_stmt (bsi);
258 tree op = gimple_phi_arg_def (stmt, e->dest_idx);
260 if (!is_gimple_reg (gimple_phi_result (stmt)))
262 if (TREE_CODE (op) != SSA_NAME
263 && test_nonssa_use (stmt, op, non_ssa_vars))
273 VEC_free (basic_block, heap, worklist);
277 /* If STMT is a call, check the callee against a list of forbidden
278 predicate functions. If a match is found, look for uses of the
279 call result in condition statements that compare against zero.
280 For each such use, find the block targeted by the condition
281 statement for the nonzero result, and set the bit for this block
282 in the forbidden dominators bitmap. The purpose of this is to avoid
283 selecting a split point where we are likely to lose the chance
284 to optimize away an unused function call. */
287 check_forbidden_calls (gimple stmt)
289 imm_use_iterator use_iter;
293 /* At the moment, __builtin_constant_p is the only forbidden
294 predicate function call (see PR49642). */
295 if (!gimple_call_builtin_p (stmt, BUILT_IN_CONSTANT_P))
298 lhs = gimple_call_lhs (stmt);
300 if (!lhs || TREE_CODE (lhs) != SSA_NAME)
303 FOR_EACH_IMM_USE_FAST (use_p, use_iter, lhs)
306 basic_block use_bb, forbidden_bb;
308 edge true_edge, false_edge;
309 gimple use_stmt = USE_STMT (use_p);
311 if (gimple_code (use_stmt) != GIMPLE_COND)
314 /* Assuming canonical form for GIMPLE_COND here, with constant
315 in second position. */
316 op1 = gimple_cond_rhs (use_stmt);
317 code = gimple_cond_code (use_stmt);
318 use_bb = gimple_bb (use_stmt);
320 extract_true_false_edges_from_block (use_bb, &true_edge, &false_edge);
322 /* We're only interested in comparisons that distinguish
323 unambiguously from zero. */
324 if (!integer_zerop (op1) || code == LE_EXPR || code == GE_EXPR)
328 forbidden_bb = false_edge->dest;
330 forbidden_bb = true_edge->dest;
332 bitmap_set_bit (forbidden_dominators, forbidden_bb->index);
336 /* If BB is dominated by any block in the forbidden dominators set,
337 return TRUE; else FALSE. */
340 dominated_by_forbidden (basic_block bb)
345 EXECUTE_IF_SET_IN_BITMAP (forbidden_dominators, 1, dom_bb, bi)
347 if (dominated_by_p (CDI_DOMINATORS, bb, BASIC_BLOCK (dom_bb)))
354 /* We found an split_point CURRENT. NON_SSA_VARS is bitmap of all non ssa
355 variables used and RETURN_BB is return basic block.
356 See if we can split function here. */
359 consider_split (struct split_point *current, bitmap non_ssa_vars,
360 basic_block return_bb)
363 unsigned int num_args = 0;
364 unsigned int call_overhead;
367 gimple_stmt_iterator bsi;
369 int incoming_freq = 0;
372 if (dump_file && (dump_flags & TDF_DETAILS))
373 dump_split_point (dump_file, current);
375 FOR_EACH_EDGE (e, ei, current->entry_bb->preds)
376 if (!bitmap_bit_p (current->split_bbs, e->src->index))
377 incoming_freq += EDGE_FREQUENCY (e);
379 /* Do not split when we would end up calling function anyway. */
381 >= (ENTRY_BLOCK_PTR->frequency
382 * PARAM_VALUE (PARAM_PARTIAL_INLINING_ENTRY_PROBABILITY) / 100))
384 if (dump_file && (dump_flags & TDF_DETAILS))
386 " Refused: incoming frequency is too large.\n");
390 if (!current->header_size)
392 if (dump_file && (dump_flags & TDF_DETAILS))
393 fprintf (dump_file, " Refused: header empty\n");
397 /* Verify that PHI args on entry are either virtual or all their operands
398 incoming from header are the same. */
399 for (bsi = gsi_start_phis (current->entry_bb); !gsi_end_p (bsi); gsi_next (&bsi))
401 gimple stmt = gsi_stmt (bsi);
404 if (!is_gimple_reg (gimple_phi_result (stmt)))
406 for (i = 0; i < gimple_phi_num_args (stmt); i++)
408 edge e = gimple_phi_arg_edge (stmt, i);
409 if (!bitmap_bit_p (current->split_bbs, e->src->index))
411 tree edge_val = gimple_phi_arg_def (stmt, i);
412 if (val && edge_val != val)
414 if (dump_file && (dump_flags & TDF_DETAILS))
416 " Refused: entry BB has PHI with multiple variants\n");
425 /* See what argument we will pass to the split function and compute
427 call_overhead = eni_size_weights.call_cost;
428 for (parm = DECL_ARGUMENTS (current_function_decl); parm;
429 parm = DECL_CHAIN (parm))
431 if (!is_gimple_reg (parm))
433 if (bitmap_bit_p (non_ssa_vars, DECL_UID (parm)))
435 if (dump_file && (dump_flags & TDF_DETAILS))
437 " Refused: need to pass non-ssa param values\n");
441 else if (gimple_default_def (cfun, parm)
442 && bitmap_bit_p (current->ssa_names_to_pass,
443 SSA_NAME_VERSION (gimple_default_def
446 if (!VOID_TYPE_P (TREE_TYPE (parm)))
447 call_overhead += estimate_move_cost (TREE_TYPE (parm));
451 if (!VOID_TYPE_P (TREE_TYPE (current_function_decl)))
452 call_overhead += estimate_move_cost (TREE_TYPE (current_function_decl));
454 if (current->split_size <= call_overhead)
456 if (dump_file && (dump_flags & TDF_DETAILS))
458 " Refused: split size is smaller than call overhead\n");
461 if (current->header_size + call_overhead
462 >= (unsigned int)(DECL_DECLARED_INLINE_P (current_function_decl)
463 ? MAX_INLINE_INSNS_SINGLE
464 : MAX_INLINE_INSNS_AUTO))
466 if (dump_file && (dump_flags & TDF_DETAILS))
468 " Refused: header size is too large for inline candidate\n");
472 /* FIXME: we currently can pass only SSA function parameters to the split
473 arguments. Once parm_adjustment infrastructure is supported by cloning,
474 we can pass more than that. */
475 if (num_args != bitmap_count_bits (current->ssa_names_to_pass))
478 if (dump_file && (dump_flags & TDF_DETAILS))
480 " Refused: need to pass non-param values\n");
484 /* When there are non-ssa vars used in the split region, see if they
485 are used in the header region. If so, reject the split.
486 FIXME: we can use nested function support to access both. */
487 if (!bitmap_empty_p (non_ssa_vars)
488 && !verify_non_ssa_vars (current, non_ssa_vars, return_bb))
490 if (dump_file && (dump_flags & TDF_DETAILS))
492 " Refused: split part has non-ssa uses\n");
496 /* If the split point is dominated by a forbidden block, reject
498 if (!bitmap_empty_p (forbidden_dominators)
499 && dominated_by_forbidden (current->entry_bb))
501 if (dump_file && (dump_flags & TDF_DETAILS))
503 " Refused: split point dominated by forbidden block\n");
507 /* See if retval used by return bb is computed by header or split part.
508 When it is computed by split part, we need to produce return statement
509 in the split part and add code to header to pass it around.
511 This is bit tricky to test:
512 1) When there is no return_bb or no return value, we always pass
514 2) Invariants are always computed by caller.
515 3) For SSA we need to look if defining statement is in header or split part
516 4) For non-SSA we need to look where the var is computed. */
517 retval = find_retval (return_bb);
519 current->split_part_set_retval = true;
520 else if (is_gimple_min_invariant (retval))
521 current->split_part_set_retval = false;
522 /* Special case is value returned by reference we record as if it was non-ssa
523 set to result_decl. */
524 else if (TREE_CODE (retval) == SSA_NAME
525 && TREE_CODE (SSA_NAME_VAR (retval)) == RESULT_DECL
526 && DECL_BY_REFERENCE (DECL_RESULT (current_function_decl)))
527 current->split_part_set_retval
528 = bitmap_bit_p (non_ssa_vars, DECL_UID (SSA_NAME_VAR (retval)));
529 else if (TREE_CODE (retval) == SSA_NAME)
530 current->split_part_set_retval
531 = (!SSA_NAME_IS_DEFAULT_DEF (retval)
532 && (bitmap_bit_p (current->split_bbs,
533 gimple_bb (SSA_NAME_DEF_STMT (retval))->index)
534 || gimple_bb (SSA_NAME_DEF_STMT (retval)) == return_bb));
535 else if (TREE_CODE (retval) == PARM_DECL)
536 current->split_part_set_retval = false;
537 else if (TREE_CODE (retval) == VAR_DECL
538 || TREE_CODE (retval) == RESULT_DECL)
539 current->split_part_set_retval
540 = bitmap_bit_p (non_ssa_vars, DECL_UID (retval));
542 current->split_part_set_retval = true;
544 /* split_function fixes up at most one PHI non-virtual PHI node in return_bb,
545 for the return value. If there are other PHIs, give up. */
546 if (return_bb != EXIT_BLOCK_PTR)
548 gimple_stmt_iterator psi;
550 for (psi = gsi_start_phis (return_bb); !gsi_end_p (psi); gsi_next (&psi))
551 if (is_gimple_reg (gimple_phi_result (gsi_stmt (psi)))
553 && current->split_part_set_retval
554 && TREE_CODE (retval) == SSA_NAME
555 && !DECL_BY_REFERENCE (DECL_RESULT (current_function_decl))
556 && SSA_NAME_DEF_STMT (retval) == gsi_stmt (psi)))
558 if (dump_file && (dump_flags & TDF_DETAILS))
560 " Refused: return bb has extra PHIs\n");
565 if (dump_file && (dump_flags & TDF_DETAILS))
566 fprintf (dump_file, " Accepted!\n");
568 /* At the moment chose split point with lowest frequency and that leaves
569 out smallest size of header.
570 In future we might re-consider this heuristics. */
571 if (!best_split_point.split_bbs
572 || best_split_point.entry_bb->frequency > current->entry_bb->frequency
573 || (best_split_point.entry_bb->frequency == current->entry_bb->frequency
574 && best_split_point.split_size < current->split_size))
577 if (dump_file && (dump_flags & TDF_DETAILS))
578 fprintf (dump_file, " New best split point!\n");
579 if (best_split_point.ssa_names_to_pass)
581 BITMAP_FREE (best_split_point.ssa_names_to_pass);
582 BITMAP_FREE (best_split_point.split_bbs);
584 best_split_point = *current;
585 best_split_point.ssa_names_to_pass = BITMAP_ALLOC (NULL);
586 bitmap_copy (best_split_point.ssa_names_to_pass,
587 current->ssa_names_to_pass);
588 best_split_point.split_bbs = BITMAP_ALLOC (NULL);
589 bitmap_copy (best_split_point.split_bbs, current->split_bbs);
593 /* Return basic block containing RETURN statement. We allow basic blocks
597 but return_bb can not be more complex than this.
598 If nothing is found, return EXIT_BLOCK_PTR.
600 When there are multiple RETURN statement, chose one with return value,
601 since that one is more likely shared by multiple code paths.
603 Return BB is special, because for function splitting it is the only
604 basic block that is duplicated in between header and split part of the
607 TODO: We might support multiple return blocks. */
610 find_return_bb (void)
613 basic_block return_bb = EXIT_BLOCK_PTR;
614 gimple_stmt_iterator bsi;
615 bool found_return = false;
616 tree retval = NULL_TREE;
618 if (!single_pred_p (EXIT_BLOCK_PTR))
621 e = single_pred_edge (EXIT_BLOCK_PTR);
622 for (bsi = gsi_last_bb (e->src); !gsi_end_p (bsi); gsi_prev (&bsi))
624 gimple stmt = gsi_stmt (bsi);
625 if (gimple_code (stmt) == GIMPLE_LABEL || is_gimple_debug (stmt))
627 else if (gimple_code (stmt) == GIMPLE_ASSIGN
629 && gimple_assign_single_p (stmt)
630 && (auto_var_in_fn_p (gimple_assign_rhs1 (stmt),
631 current_function_decl)
632 || is_gimple_min_invariant (gimple_assign_rhs1 (stmt)))
633 && retval == gimple_assign_lhs (stmt))
635 else if (gimple_code (stmt) == GIMPLE_RETURN)
638 retval = gimple_return_retval (stmt);
643 if (gsi_end_p (bsi) && found_return)
649 /* Given return basic block RETURN_BB, see where return value is really
652 find_retval (basic_block return_bb)
654 gimple_stmt_iterator bsi;
655 for (bsi = gsi_start_bb (return_bb); !gsi_end_p (bsi); gsi_next (&bsi))
656 if (gimple_code (gsi_stmt (bsi)) == GIMPLE_RETURN)
657 return gimple_return_retval (gsi_stmt (bsi));
658 else if (gimple_code (gsi_stmt (bsi)) == GIMPLE_ASSIGN)
659 return gimple_assign_rhs1 (gsi_stmt (bsi));
663 /* Callback for walk_stmt_load_store_addr_ops. If T is non-SSA automatic
664 variable, mark it as used in bitmap passed via DATA.
665 Return true when access to T prevents splitting the function. */
668 mark_nonssa_use (gimple stmt ATTRIBUTE_UNUSED, tree t, void *data)
670 t = get_base_address (t);
672 if (!t || is_gimple_reg (t))
675 /* At present we can't pass non-SSA arguments to split function.
676 FIXME: this can be relaxed by passing references to arguments. */
677 if (TREE_CODE (t) == PARM_DECL)
679 if (dump_file && (dump_flags & TDF_DETAILS))
681 "Cannot split: use of non-ssa function parameter.\n");
685 if ((TREE_CODE (t) == VAR_DECL
686 && auto_var_in_fn_p (t, current_function_decl))
687 || TREE_CODE (t) == RESULT_DECL
688 || TREE_CODE (t) == LABEL_DECL)
689 bitmap_set_bit ((bitmap)data, DECL_UID (t));
691 /* For DECL_BY_REFERENCE, the return value is actually a pointer. We want
692 to pretend that the value pointed to is actual result decl. */
693 if ((TREE_CODE (t) == MEM_REF || INDIRECT_REF_P (t))
694 && TREE_CODE (TREE_OPERAND (t, 0)) == SSA_NAME
695 && TREE_CODE (SSA_NAME_VAR (TREE_OPERAND (t, 0))) == RESULT_DECL
696 && DECL_BY_REFERENCE (DECL_RESULT (current_function_decl)))
698 bitmap_bit_p ((bitmap)data,
699 DECL_UID (DECL_RESULT (current_function_decl)));
704 /* Compute local properties of basic block BB we collect when looking for
705 split points. We look for ssa defs and store them in SET_SSA_NAMES,
706 for ssa uses and store them in USED_SSA_NAMES and for any non-SSA automatic
707 vars stored in NON_SSA_VARS.
709 When BB has edge to RETURN_BB, collect uses in RETURN_BB too.
711 Return false when BB contains something that prevents it from being put into
715 visit_bb (basic_block bb, basic_block return_bb,
716 bitmap set_ssa_names, bitmap used_ssa_names,
719 gimple_stmt_iterator bsi;
722 bool can_split = true;
724 for (bsi = gsi_start_bb (bb); !gsi_end_p (bsi); gsi_next (&bsi))
726 gimple stmt = gsi_stmt (bsi);
731 if (is_gimple_debug (stmt))
734 /* FIXME: We can split regions containing EH. We can not however
735 split RESX, EH_DISPATCH and EH_POINTER referring to same region
736 into different partitions. This would require tracking of
737 EH regions and checking in consider_split_point if they
738 are not used elsewhere. */
739 if (gimple_code (stmt) == GIMPLE_RESX)
741 if (dump_file && (dump_flags & TDF_DETAILS))
742 fprintf (dump_file, "Cannot split: resx.\n");
745 if (gimple_code (stmt) == GIMPLE_EH_DISPATCH)
747 if (dump_file && (dump_flags & TDF_DETAILS))
748 fprintf (dump_file, "Cannot split: eh dispatch.\n");
752 /* Check builtins that prevent splitting. */
753 if (gimple_code (stmt) == GIMPLE_CALL
754 && (decl = gimple_call_fndecl (stmt)) != NULL_TREE
755 && DECL_BUILT_IN (decl)
756 && DECL_BUILT_IN_CLASS (decl) == BUILT_IN_NORMAL)
757 switch (DECL_FUNCTION_CODE (decl))
759 /* FIXME: once we will allow passing non-parm values to split part,
760 we need to be sure to handle correct builtin_stack_save and
761 builtin_stack_restore. At the moment we are safe; there is no
762 way to store builtin_stack_save result in non-SSA variable
763 since all calls to those are compiler generated. */
765 case BUILT_IN_APPLY_ARGS:
766 case BUILT_IN_VA_START:
767 if (dump_file && (dump_flags & TDF_DETAILS))
769 "Cannot split: builtin_apply and va_start.\n");
772 case BUILT_IN_EH_POINTER:
773 if (dump_file && (dump_flags & TDF_DETAILS))
774 fprintf (dump_file, "Cannot split: builtin_eh_pointer.\n");
781 FOR_EACH_SSA_TREE_OPERAND (op, stmt, iter, SSA_OP_DEF)
782 bitmap_set_bit (set_ssa_names, SSA_NAME_VERSION (op));
783 FOR_EACH_SSA_TREE_OPERAND (op, stmt, iter, SSA_OP_USE)
784 bitmap_set_bit (used_ssa_names, SSA_NAME_VERSION (op));
785 can_split &= !walk_stmt_load_store_addr_ops (stmt, non_ssa_vars,
790 for (bsi = gsi_start_phis (bb); !gsi_end_p (bsi); gsi_next (&bsi))
792 gimple stmt = gsi_stmt (bsi);
795 if (is_gimple_debug (stmt))
797 if (!is_gimple_reg (gimple_phi_result (stmt)))
799 bitmap_set_bit (set_ssa_names,
800 SSA_NAME_VERSION (gimple_phi_result (stmt)));
801 for (i = 0; i < gimple_phi_num_args (stmt); i++)
803 tree op = gimple_phi_arg_def (stmt, i);
804 if (TREE_CODE (op) == SSA_NAME)
805 bitmap_set_bit (used_ssa_names, SSA_NAME_VERSION (op));
807 can_split &= !walk_stmt_load_store_addr_ops (stmt, non_ssa_vars,
812 /* Record also uses coming from PHI operand in return BB. */
813 FOR_EACH_EDGE (e, ei, bb->succs)
814 if (e->dest == return_bb)
816 for (bsi = gsi_start_phis (return_bb); !gsi_end_p (bsi); gsi_next (&bsi))
818 gimple stmt = gsi_stmt (bsi);
819 tree op = gimple_phi_arg_def (stmt, e->dest_idx);
821 if (is_gimple_debug (stmt))
823 if (!is_gimple_reg (gimple_phi_result (stmt)))
825 if (TREE_CODE (op) == SSA_NAME)
826 bitmap_set_bit (used_ssa_names, SSA_NAME_VERSION (op));
828 can_split &= !mark_nonssa_use (stmt, op, non_ssa_vars);
834 /* Stack entry for recursive DFS walk in find_split_point. */
838 /* Basic block we are examining. */
841 /* SSA names set and used by the BB and all BBs reachable
842 from it via DFS walk. */
843 bitmap set_ssa_names, used_ssa_names;
846 /* All BBS visited from this BB via DFS walk. */
849 /* Last examined edge in DFS walk. Since we walk unoriented graph,
850 the value is up to sum of incoming and outgoing edges of BB. */
851 unsigned int edge_num;
853 /* Stack entry index of earliest BB reachable from current BB
854 or any BB visited later in DFS walk. */
857 /* Overall time and size of all BBs reached from this BB in DFS walk. */
858 int overall_time, overall_size;
860 /* When false we can not split on this BB. */
863 DEF_VEC_O(stack_entry);
864 DEF_VEC_ALLOC_O(stack_entry,heap);
867 /* Find all articulations and call consider_split on them.
868 OVERALL_TIME and OVERALL_SIZE is time and size of the function.
870 We perform basic algorithm for finding an articulation in a graph
871 created from CFG by considering it to be an unoriented graph.
873 The articulation is discovered via DFS walk. We collect earliest
874 basic block on stack that is reachable via backward edge. Articulation
875 is any basic block such that there is no backward edge bypassing it.
876 To reduce stack usage we maintain heap allocated stack in STACK vector.
877 AUX pointer of BB is set to index it appears in the stack or -1 once
878 it is visited and popped off the stack.
880 The algorithm finds articulation after visiting the whole component
881 reachable by it. This makes it convenient to collect information about
882 the component used by consider_split. */
885 find_split_points (int overall_time, int overall_size)
888 VEC(stack_entry, heap) *stack = NULL;
890 basic_block return_bb = find_return_bb ();
891 struct split_point current;
893 current.header_time = overall_time;
894 current.header_size = overall_size;
895 current.split_time = 0;
896 current.split_size = 0;
897 current.ssa_names_to_pass = BITMAP_ALLOC (NULL);
899 first.bb = ENTRY_BLOCK_PTR;
901 first.overall_time = 0;
902 first.overall_size = 0;
903 first.earliest = INT_MAX;
904 first.set_ssa_names = 0;
905 first.used_ssa_names = 0;
906 first.bbs_visited = 0;
907 VEC_safe_push (stack_entry, heap, stack, &first);
908 ENTRY_BLOCK_PTR->aux = (void *)(intptr_t)-1;
910 while (!VEC_empty (stack_entry, stack))
912 stack_entry *entry = VEC_last (stack_entry, stack);
914 /* We are walking an acyclic graph, so edge_num counts
915 succ and pred edges together. However when considering
916 articulation, we want to have processed everything reachable
917 from articulation but nothing that reaches into it. */
918 if (entry->edge_num == EDGE_COUNT (entry->bb->succs)
919 && entry->bb != ENTRY_BLOCK_PTR)
921 int pos = VEC_length (stack_entry, stack);
922 entry->can_split &= visit_bb (entry->bb, return_bb,
923 entry->set_ssa_names,
924 entry->used_ssa_names,
925 entry->non_ssa_vars);
926 if (pos <= entry->earliest && !entry->can_split
927 && dump_file && (dump_flags & TDF_DETAILS))
929 "found articulation at bb %i but can not split\n",
931 if (pos <= entry->earliest && entry->can_split)
933 if (dump_file && (dump_flags & TDF_DETAILS))
934 fprintf (dump_file, "found articulation at bb %i\n",
936 current.entry_bb = entry->bb;
937 current.ssa_names_to_pass = BITMAP_ALLOC (NULL);
938 bitmap_and_compl (current.ssa_names_to_pass,
939 entry->used_ssa_names, entry->set_ssa_names);
940 current.header_time = overall_time - entry->overall_time;
941 current.header_size = overall_size - entry->overall_size;
942 current.split_time = entry->overall_time;
943 current.split_size = entry->overall_size;
944 current.split_bbs = entry->bbs_visited;
945 consider_split (¤t, entry->non_ssa_vars, return_bb);
946 BITMAP_FREE (current.ssa_names_to_pass);
949 /* Do actual DFS walk. */
951 < (EDGE_COUNT (entry->bb->succs)
952 + EDGE_COUNT (entry->bb->preds)))
956 if (entry->edge_num < EDGE_COUNT (entry->bb->succs))
958 e = EDGE_SUCC (entry->bb, entry->edge_num);
963 e = EDGE_PRED (entry->bb, entry->edge_num
964 - EDGE_COUNT (entry->bb->succs));
970 /* New BB to visit, push it to the stack. */
971 if (dest != return_bb && dest != EXIT_BLOCK_PTR
974 stack_entry new_entry;
977 new_entry.edge_num = 0;
978 new_entry.overall_time
979 = VEC_index (bb_info, bb_info_vec, dest->index)->time;
980 new_entry.overall_size
981 = VEC_index (bb_info, bb_info_vec, dest->index)->size;
982 new_entry.earliest = INT_MAX;
983 new_entry.set_ssa_names = BITMAP_ALLOC (NULL);
984 new_entry.used_ssa_names = BITMAP_ALLOC (NULL);
985 new_entry.bbs_visited = BITMAP_ALLOC (NULL);
986 new_entry.non_ssa_vars = BITMAP_ALLOC (NULL);
987 new_entry.can_split = true;
988 bitmap_set_bit (new_entry.bbs_visited, dest->index);
989 VEC_safe_push (stack_entry, heap, stack, &new_entry);
990 dest->aux = (void *)(intptr_t)VEC_length (stack_entry, stack);
992 /* Back edge found, record the earliest point. */
993 else if ((intptr_t)dest->aux > 0
994 && (intptr_t)dest->aux < entry->earliest)
995 entry->earliest = (intptr_t)dest->aux;
997 /* We are done with examining the edges. Pop off the value from stack
998 and merge stuff we accumulate during the walk. */
999 else if (entry->bb != ENTRY_BLOCK_PTR)
1001 stack_entry *prev = VEC_index (stack_entry, stack,
1002 VEC_length (stack_entry, stack) - 2);
1004 entry->bb->aux = (void *)(intptr_t)-1;
1005 prev->can_split &= entry->can_split;
1006 if (prev->set_ssa_names)
1008 bitmap_ior_into (prev->set_ssa_names, entry->set_ssa_names);
1009 bitmap_ior_into (prev->used_ssa_names, entry->used_ssa_names);
1010 bitmap_ior_into (prev->bbs_visited, entry->bbs_visited);
1011 bitmap_ior_into (prev->non_ssa_vars, entry->non_ssa_vars);
1013 if (prev->earliest > entry->earliest)
1014 prev->earliest = entry->earliest;
1015 prev->overall_time += entry->overall_time;
1016 prev->overall_size += entry->overall_size;
1017 BITMAP_FREE (entry->set_ssa_names);
1018 BITMAP_FREE (entry->used_ssa_names);
1019 BITMAP_FREE (entry->bbs_visited);
1020 BITMAP_FREE (entry->non_ssa_vars);
1021 VEC_pop (stack_entry, stack);
1024 VEC_pop (stack_entry, stack);
1026 ENTRY_BLOCK_PTR->aux = NULL;
1029 VEC_free (stack_entry, heap, stack);
1030 BITMAP_FREE (current.ssa_names_to_pass);
1033 /* Split function at SPLIT_POINT. */
1036 split_function (struct split_point *split_point)
1038 VEC (tree, heap) *args_to_pass = NULL;
1039 bitmap args_to_skip = BITMAP_ALLOC (NULL);
1042 struct cgraph_node *node, *cur_node = cgraph_node (current_function_decl);
1043 basic_block return_bb = find_return_bb ();
1044 basic_block call_bb;
1045 gimple_stmt_iterator gsi;
1049 tree retval = NULL, real_retval = NULL;
1050 bool split_part_return_p = false;
1051 gimple last_stmt = NULL;
1057 fprintf (dump_file, "\n\nSplitting function at:\n");
1058 dump_split_point (dump_file, split_point);
1061 if (cur_node->local.can_change_signature
1062 && !TYPE_ATTRIBUTES (TREE_TYPE (cur_node->decl)))
1063 args_to_skip = BITMAP_ALLOC (NULL);
1065 args_to_skip = NULL;
1067 /* Collect the parameters of new function and args_to_skip bitmap. */
1068 for (parm = DECL_ARGUMENTS (current_function_decl);
1069 parm; parm = DECL_CHAIN (parm), num++)
1071 && (!is_gimple_reg (parm)
1072 || !gimple_default_def (cfun, parm)
1073 || !bitmap_bit_p (split_point->ssa_names_to_pass,
1074 SSA_NAME_VERSION (gimple_default_def (cfun,
1076 bitmap_set_bit (args_to_skip, num);
1079 /* This parm might not have been used up to now, but is going to be
1080 used, hence register it. */
1081 add_referenced_var (parm);
1082 if (is_gimple_reg (parm))
1084 arg = gimple_default_def (cfun, parm);
1087 arg = make_ssa_name (parm, gimple_build_nop ());
1088 set_default_def (parm, arg);
1094 if (!useless_type_conversion_p (DECL_ARG_TYPE (parm), TREE_TYPE (arg)))
1095 arg = fold_convert (DECL_ARG_TYPE (parm), arg);
1096 VEC_safe_push (tree, heap, args_to_pass, arg);
1099 /* See if the split function will return. */
1100 FOR_EACH_EDGE (e, ei, return_bb->preds)
1101 if (bitmap_bit_p (split_point->split_bbs, e->src->index))
1104 split_part_return_p = true;
1106 /* Add return block to what will become the split function.
1107 We do not return; no return block is needed. */
1108 if (!split_part_return_p)
1110 /* We have no return block, so nothing is needed. */
1111 else if (return_bb == EXIT_BLOCK_PTR)
1113 /* When we do not want to return value, we need to construct
1114 new return block with empty return statement.
1115 FIXME: Once we are able to change return type, we should change function
1116 to return void instead of just outputting function with undefined return
1117 value. For structures this affects quality of codegen. */
1118 else if (!split_point->split_part_set_retval
1119 && find_retval (return_bb))
1121 bool redirected = true;
1122 basic_block new_return_bb = create_basic_block (NULL, 0, return_bb);
1123 gimple_stmt_iterator gsi = gsi_start_bb (new_return_bb);
1124 gsi_insert_after (&gsi, gimple_build_return (NULL), GSI_NEW_STMT);
1128 FOR_EACH_EDGE (e, ei, return_bb->preds)
1129 if (bitmap_bit_p (split_point->split_bbs, e->src->index))
1131 new_return_bb->count += e->count;
1132 new_return_bb->frequency += EDGE_FREQUENCY (e);
1133 redirect_edge_and_branch (e, new_return_bb);
1138 e = make_edge (new_return_bb, EXIT_BLOCK_PTR, 0);
1139 e->probability = REG_BR_PROB_BASE;
1140 e->count = new_return_bb->count;
1141 bitmap_set_bit (split_point->split_bbs, new_return_bb->index);
1143 /* When we pass around the value, use existing return block. */
1145 bitmap_set_bit (split_point->split_bbs, return_bb->index);
1147 /* If RETURN_BB has virtual operand PHIs, they must be removed and the
1148 virtual operand marked for renaming as we change the CFG in a way that
1149 tree-inline is not able to compensate for.
1151 Note this can happen whether or not we have a return value. If we have
1152 a return value, then RETURN_BB may have PHIs for real operands too. */
1153 if (return_bb != EXIT_BLOCK_PTR)
1155 for (gsi = gsi_start_phis (return_bb); !gsi_end_p (gsi);)
1157 gimple stmt = gsi_stmt (gsi);
1158 if (is_gimple_reg (gimple_phi_result (stmt)))
1163 mark_virtual_phi_result_for_renaming (stmt);
1164 remove_phi_node (&gsi, true);
1168 /* Now create the actual clone. */
1169 rebuild_cgraph_edges ();
1170 node = cgraph_function_versioning (cur_node, NULL, NULL, args_to_skip,
1171 split_point->split_bbs,
1172 split_point->entry_bb, "part");
1173 /* For usual cloning it is enough to clear builtin only when signature
1174 changes. For partial inlining we however can not expect the part
1175 of builtin implementation to have same semantic as the whole. */
1176 if (DECL_BUILT_IN (node->decl))
1178 DECL_BUILT_IN_CLASS (node->decl) = NOT_BUILT_IN;
1179 DECL_FUNCTION_CODE (node->decl) = (enum built_in_function) 0;
1181 cgraph_node_remove_callees (cur_node);
1182 if (!split_part_return_p)
1183 TREE_THIS_VOLATILE (node->decl) = 1;
1185 dump_function_to_file (node->decl, dump_file, dump_flags);
1187 /* Create the basic block we place call into. It is the entry basic block
1188 split after last label. */
1189 call_bb = split_point->entry_bb;
1190 for (gsi = gsi_start_bb (call_bb); !gsi_end_p (gsi);)
1191 if (gimple_code (gsi_stmt (gsi)) == GIMPLE_LABEL)
1193 last_stmt = gsi_stmt (gsi);
1198 e = split_block (split_point->entry_bb, last_stmt);
1201 /* Produce the call statement. */
1202 gsi = gsi_last_bb (call_bb);
1203 FOR_EACH_VEC_ELT (tree, args_to_pass, i, arg)
1204 if (!is_gimple_val (arg))
1206 arg = force_gimple_operand_gsi (&gsi, arg, true, NULL_TREE,
1207 false, GSI_CONTINUE_LINKING);
1208 VEC_replace (tree, args_to_pass, i, arg);
1210 call = gimple_build_call_vec (node->decl, args_to_pass);
1211 gimple_set_block (call, DECL_INITIAL (current_function_decl));
1213 /* We avoid address being taken on any variable used by split part,
1214 so return slot optimization is always possible. Moreover this is
1215 required to make DECL_BY_REFERENCE work. */
1216 if (aggregate_value_p (DECL_RESULT (current_function_decl),
1217 TREE_TYPE (current_function_decl)))
1218 gimple_call_set_return_slot_opt (call, true);
1220 /* Update return value. This is bit tricky. When we do not return,
1221 do nothing. When we return we might need to update return_bb
1222 or produce a new return statement. */
1223 if (!split_part_return_p)
1224 gsi_insert_after (&gsi, call, GSI_NEW_STMT);
1227 e = make_edge (call_bb, return_bb,
1228 return_bb == EXIT_BLOCK_PTR ? 0 : EDGE_FALLTHRU);
1229 e->count = call_bb->count;
1230 e->probability = REG_BR_PROB_BASE;
1232 /* If there is return basic block, see what value we need to store
1233 return value into and put call just before it. */
1234 if (return_bb != EXIT_BLOCK_PTR)
1236 real_retval = retval = find_retval (return_bb);
1238 if (real_retval && split_point->split_part_set_retval)
1240 gimple_stmt_iterator psi;
1242 /* See if we need new SSA_NAME for the result.
1243 When DECL_BY_REFERENCE is true, retval is actually pointer to
1244 return value and it is constant in whole function. */
1245 if (TREE_CODE (retval) == SSA_NAME
1246 && !DECL_BY_REFERENCE (DECL_RESULT (current_function_decl)))
1248 retval = make_ssa_name (SSA_NAME_VAR (retval), call);
1250 /* See if there is PHI defining return value. */
1251 for (psi = gsi_start_phis (return_bb);
1252 !gsi_end_p (psi); gsi_next (&psi))
1253 if (is_gimple_reg (gimple_phi_result (gsi_stmt (psi))))
1256 /* When there is PHI, just update its value. */
1257 if (TREE_CODE (retval) == SSA_NAME
1258 && !gsi_end_p (psi))
1259 add_phi_arg (gsi_stmt (psi), retval, e, UNKNOWN_LOCATION);
1260 /* Otherwise update the return BB itself.
1261 find_return_bb allows at most one assignment to return value,
1262 so update first statement. */
1265 gimple_stmt_iterator bsi;
1266 for (bsi = gsi_start_bb (return_bb); !gsi_end_p (bsi);
1268 if (gimple_code (gsi_stmt (bsi)) == GIMPLE_RETURN)
1270 gimple_return_set_retval (gsi_stmt (bsi), retval);
1273 else if (gimple_code (gsi_stmt (bsi)) == GIMPLE_ASSIGN)
1275 gimple_assign_set_rhs1 (gsi_stmt (bsi), retval);
1278 update_stmt (gsi_stmt (bsi));
1281 if (DECL_BY_REFERENCE (DECL_RESULT (current_function_decl)))
1282 gimple_call_set_lhs (call, build_simple_mem_ref (retval));
1284 gimple_call_set_lhs (call, retval);
1286 gsi_insert_after (&gsi, call, GSI_NEW_STMT);
1288 /* We don't use return block (there is either no return in function or
1289 multiple of them). So create new basic block with return statement.
1294 if (split_point->split_part_set_retval
1295 && !VOID_TYPE_P (TREE_TYPE (TREE_TYPE (current_function_decl))))
1297 retval = DECL_RESULT (current_function_decl);
1299 /* We use temporary register to hold value when aggregate_value_p
1300 is false. Similarly for DECL_BY_REFERENCE we must avoid extra
1302 if (!aggregate_value_p (retval, TREE_TYPE (current_function_decl))
1303 && !DECL_BY_REFERENCE (retval))
1304 retval = create_tmp_reg (TREE_TYPE (retval), NULL);
1305 if (is_gimple_reg (retval))
1307 /* When returning by reference, there is only one SSA name
1308 assigned to RESULT_DECL (that is pointer to return value).
1309 Look it up or create new one if it is missing. */
1310 if (DECL_BY_REFERENCE (retval))
1313 if ((retval_name = gimple_default_def (cfun, retval))
1315 retval = retval_name;
1318 retval_name = make_ssa_name (retval,
1319 gimple_build_nop ());
1320 set_default_def (retval, retval_name);
1321 retval = retval_name;
1324 /* Otherwise produce new SSA name for return value. */
1326 retval = make_ssa_name (retval, call);
1328 if (DECL_BY_REFERENCE (DECL_RESULT (current_function_decl)))
1329 gimple_call_set_lhs (call, build_simple_mem_ref (retval));
1331 gimple_call_set_lhs (call, retval);
1333 gsi_insert_after (&gsi, call, GSI_NEW_STMT);
1334 ret = gimple_build_return (retval);
1335 gsi_insert_after (&gsi, ret, GSI_NEW_STMT);
1338 free_dominance_info (CDI_DOMINATORS);
1339 free_dominance_info (CDI_POST_DOMINATORS);
1340 compute_inline_parameters (node);
1343 /* Execute function splitting pass. */
1346 execute_split_functions (void)
1348 gimple_stmt_iterator bsi;
1350 int overall_time = 0, overall_size = 0;
1352 struct cgraph_node *node = cgraph_node (current_function_decl);
1354 if (flags_from_decl_or_type (current_function_decl) & ECF_NORETURN)
1357 fprintf (dump_file, "Not splitting: noreturn function.\n");
1360 if (MAIN_NAME_P (DECL_NAME (current_function_decl)))
1363 fprintf (dump_file, "Not splitting: main function.\n");
1366 /* This can be relaxed; function might become inlinable after splitting
1367 away the uninlinable part. */
1368 if (!node->local.inlinable)
1371 fprintf (dump_file, "Not splitting: not inlinable.\n");
1374 if (node->local.disregard_inline_limits)
1377 fprintf (dump_file, "Not splitting: disregarding inline limits.\n");
1380 /* This can be relaxed; most of versioning tests actually prevents
1382 if (!tree_versionable_function_p (current_function_decl))
1385 fprintf (dump_file, "Not splitting: not versionable.\n");
1388 /* FIXME: we could support this. */
1389 if (DECL_STRUCT_FUNCTION (current_function_decl)->static_chain_decl)
1392 fprintf (dump_file, "Not splitting: nested function.\n");
1396 /* See if it makes sense to try to split.
1397 It makes sense to split if we inline, that is if we have direct calls to
1398 handle or direct calls are possibly going to appear as result of indirect
1399 inlining or LTO. Also handle -fprofile-generate as LTO to allow non-LTO
1400 training for LTO -fprofile-use build.
1402 Note that we are not completely conservative about disqualifying functions
1403 called once. It is possible that the caller is called more then once and
1404 then inlining would still benefit. */
1405 if ((!node->callers || !node->callers->next_caller)
1406 && !node->address_taken
1407 && (!flag_lto || !node->local.externally_visible))
1410 fprintf (dump_file, "Not splitting: not called directly "
1411 "or called once.\n");
1415 /* FIXME: We can actually split if splitting reduces call overhead. */
1416 if (!flag_inline_small_functions
1417 && !DECL_DECLARED_INLINE_P (current_function_decl))
1420 fprintf (dump_file, "Not splitting: not autoinlining and function"
1421 " is not inline.\n");
1425 /* Initialize bitmap to track forbidden calls. */
1426 forbidden_dominators = BITMAP_ALLOC (NULL);
1427 calculate_dominance_info (CDI_DOMINATORS);
1429 /* Compute local info about basic blocks and determine function size/time. */
1430 VEC_safe_grow_cleared (bb_info, heap, bb_info_vec, last_basic_block + 1);
1431 memset (&best_split_point, 0, sizeof (best_split_point));
1436 int freq = compute_call_stmt_bb_frequency (current_function_decl, bb);
1438 if (dump_file && (dump_flags & TDF_DETAILS))
1439 fprintf (dump_file, "Basic block %i\n", bb->index);
1441 for (bsi = gsi_start_bb (bb); !gsi_end_p (bsi); gsi_next (&bsi))
1443 int this_time, this_size;
1444 gimple stmt = gsi_stmt (bsi);
1446 this_size = estimate_num_insns (stmt, &eni_size_weights);
1447 this_time = estimate_num_insns (stmt, &eni_time_weights) * freq;
1450 check_forbidden_calls (stmt);
1452 if (dump_file && (dump_flags & TDF_DETAILS))
1454 fprintf (dump_file, " freq:%6i size:%3i time:%3i ",
1455 freq, this_size, this_time);
1456 print_gimple_stmt (dump_file, stmt, 0, 0);
1459 overall_time += time;
1460 overall_size += size;
1461 VEC_index (bb_info, bb_info_vec, bb->index)->time = time;
1462 VEC_index (bb_info, bb_info_vec, bb->index)->size = size;
1464 find_split_points (overall_time, overall_size);
1465 if (best_split_point.split_bbs)
1467 split_function (&best_split_point);
1468 BITMAP_FREE (best_split_point.ssa_names_to_pass);
1469 BITMAP_FREE (best_split_point.split_bbs);
1470 todo = TODO_update_ssa | TODO_cleanup_cfg;
1472 BITMAP_FREE (forbidden_dominators);
1473 VEC_free (bb_info, heap, bb_info_vec);
1478 /* Gate function splitting pass. When doing profile feedback, we want
1479 to execute the pass after profiling is read. So disable one in
1480 early optimization. */
1483 gate_split_functions (void)
1485 return (flag_partial_inlining
1486 && !profile_arc_flag && !flag_branch_probabilities);
1489 struct gimple_opt_pass pass_split_functions =
1493 "fnsplit", /* name */
1494 gate_split_functions, /* gate */
1495 execute_split_functions, /* execute */
1498 0, /* static_pass_number */
1499 TV_IPA_FNSPLIT, /* tv_id */
1500 PROP_cfg, /* properties_required */
1501 0, /* properties_provided */
1502 0, /* properties_destroyed */
1503 0, /* todo_flags_start */
1504 TODO_dump_func /* todo_flags_finish */
1508 /* Gate feedback driven function splitting pass.
1509 We don't need to split when profiling at all, we are producing
1510 lousy code anyway. */
1513 gate_feedback_split_functions (void)
1515 return (flag_partial_inlining
1516 && flag_branch_probabilities);
1519 /* Execute function splitting pass. */
1522 execute_feedback_split_functions (void)
1524 unsigned int retval = execute_split_functions ();
1526 retval |= TODO_rebuild_cgraph_edges;
1530 struct gimple_opt_pass pass_feedback_split_functions =
1534 "feedback_fnsplit", /* name */
1535 gate_feedback_split_functions, /* gate */
1536 execute_feedback_split_functions, /* execute */
1539 0, /* static_pass_number */
1540 TV_IPA_FNSPLIT, /* tv_id */
1541 PROP_cfg, /* properties_required */
1542 0, /* properties_provided */
1543 0, /* properties_destroyed */
1544 0, /* todo_flags_start */
1545 TODO_dump_func /* todo_flags_finish */