Remove the temporary array for reductions written to memory.
[official-gcc/graphite-test-results.git] / gcc / ipa-cp.c
blobce6fd598715b7e94404c941fd8b924d7680385e4
1 /* Interprocedural constant propagation
2 Copyright (C) 2005, 2006, 2007, 2008, 2009, 2010
3 Free Software Foundation, Inc.
4 Contributed by Razya Ladelsky <RAZYA@il.ibm.com>
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
11 version.
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
16 for more details.
18 You should have received a copy of the GNU General Public License
19 along with GCC; see the file COPYING3. If not see
20 <http://www.gnu.org/licenses/>. */
22 /* Interprocedural constant propagation. The aim of interprocedural constant
23 propagation (IPCP) is to find which function's argument has the same
24 constant value in each invocation throughout the whole program. For example,
25 consider the following program:
27 int g (int y)
29 printf ("value is %d",y);
32 int f (int x)
34 g (x);
37 int h (int y)
39 g (y);
42 void main (void)
44 f (3);
45 h (3);
49 The IPCP algorithm will find that g's formal argument y is always called
50 with the value 3.
52 The algorithm used is based on "Interprocedural Constant Propagation", by
53 Challahan David, Keith D Cooper, Ken Kennedy, Linda Torczon, Comp86, pg
54 152-161
56 The optimization is divided into three stages:
58 First stage - intraprocedural analysis
59 =======================================
60 This phase computes jump_function and modification flags.
62 A jump function for a callsite represents the values passed as an actual
63 arguments of a given callsite. There are three types of values:
64 Pass through - the caller's formal parameter is passed as an actual argument.
65 Constant - a constant is passed as an actual argument.
66 Unknown - neither of the above.
68 The jump function info, ipa_jump_func, is stored in ipa_edge_args
69 structure (defined in ipa_prop.h and pointed to by cgraph_node->aux)
70 modified_flags are defined in ipa_node_params structure
71 (defined in ipa_prop.h and pointed to by cgraph_edge->aux).
73 -ipcp_generate_summary() is the first stage driver.
75 Second stage - interprocedural analysis
76 ========================================
77 This phase does the interprocedural constant propagation.
78 It computes lattices for all formal parameters in the program
79 and their value that may be:
80 TOP - unknown.
81 BOTTOM - non constant.
82 CONSTANT - constant value.
84 Lattice describing a formal parameter p will have a constant value if all
85 callsites invoking this function have the same constant value passed to p.
87 The lattices are stored in ipcp_lattice which is itself in ipa_node_params
88 structure (defined in ipa_prop.h and pointed to by cgraph_edge->aux).
90 -ipcp_iterate_stage() is the second stage driver.
92 Third phase - transformation of function code
93 ============================================
94 Propagates the constant-valued formals into the function.
95 For each function whose parameters are constants, we create its clone.
97 Then we process the clone in two ways:
98 1. We insert an assignment statement 'parameter = const' at the beginning
99 of the cloned function.
100 2. For read-only parameters that do not live in memory, we replace all their
101 uses with the constant.
103 We also need to modify some callsites to call the cloned functions instead
104 of the original ones. For a callsite passing an argument found to be a
105 constant by IPCP, there are two different cases to handle:
106 1. A constant is passed as an argument. In this case the callsite in the
107 should be redirected to call the cloned callee.
108 2. A parameter (of the caller) passed as an argument (pass through
109 argument). In such cases both the caller and the callee have clones and
110 only the callsite in the cloned caller is redirected to call to the
111 cloned callee.
113 This update is done in two steps: First all cloned functions are created
114 during a traversal of the call graph, during which all callsites are
115 redirected to call the cloned function. Then the callsites are traversed
116 and many calls redirected back to fit the description above.
118 -ipcp_insert_stage() is the third phase driver.
121 This pass also performs devirtualization - turns virtual calls into direct
122 ones if it can prove that all invocations of the function call the same
123 callee. This is achieved by building a list of all base types (actually,
124 their BINFOs) that individual parameters can have in an iterative matter
125 just like propagating scalar constants and then examining whether virtual
126 calls which take a parameter as their object fold to the same target for all
127 these types. If we cannot enumerate all types or there is a type which does
128 not have any BINFO associated with it, cannot_devirtualize of the associated
129 parameter descriptor is set which is an equivalent of BOTTOM lattice value
130 in standard IPA constant propagation.
133 #include "config.h"
134 #include "system.h"
135 #include "coretypes.h"
136 #include "tree.h"
137 #include "target.h"
138 #include "gimple.h"
139 #include "cgraph.h"
140 #include "ipa-prop.h"
141 #include "tree-flow.h"
142 #include "tree-pass.h"
143 #include "flags.h"
144 #include "timevar.h"
145 #include "diagnostic.h"
146 #include "tree-pretty-print.h"
147 #include "tree-dump.h"
148 #include "tree-inline.h"
149 #include "fibheap.h"
150 #include "params.h"
152 /* Number of functions identified as candidates for cloning. When not cloning
153 we can simplify iterate stage not forcing it to go through the decision
154 on what is profitable and what not. */
155 static int n_cloning_candidates;
157 /* Maximal count found in program. */
158 static gcov_type max_count;
160 /* Cgraph nodes that has been completely replaced by cloning during iterate
161 * stage and will be removed after ipcp is finished. */
162 static bitmap dead_nodes;
164 static void ipcp_print_profile_data (FILE *);
165 static void ipcp_function_scale_print (FILE *);
167 /* Get the original node field of ipa_node_params associated with node NODE. */
168 static inline struct cgraph_node *
169 ipcp_get_orig_node (struct cgraph_node *node)
171 return IPA_NODE_REF (node)->ipcp_orig_node;
174 /* Return true if NODE describes a cloned/versioned function. */
175 static inline bool
176 ipcp_node_is_clone (struct cgraph_node *node)
178 return (ipcp_get_orig_node (node) != NULL);
181 /* Create ipa_node_params and its data structures for NEW_NODE. Set ORIG_NODE
182 as the ipcp_orig_node field in ipa_node_params. */
183 static void
184 ipcp_init_cloned_node (struct cgraph_node *orig_node,
185 struct cgraph_node *new_node)
187 gcc_checking_assert (ipa_node_params_vector
188 && (VEC_length (ipa_node_params_t,
189 ipa_node_params_vector)
190 > (unsigned) cgraph_max_uid));
191 gcc_checking_assert (IPA_NODE_REF (new_node)->params);
192 IPA_NODE_REF (new_node)->ipcp_orig_node = orig_node;
195 /* Return scale for NODE. */
196 static inline gcov_type
197 ipcp_get_node_scale (struct cgraph_node *node)
199 return IPA_NODE_REF (node)->count_scale;
202 /* Set COUNT as scale for NODE. */
203 static inline void
204 ipcp_set_node_scale (struct cgraph_node *node, gcov_type count)
206 IPA_NODE_REF (node)->count_scale = count;
209 /* Return whether LAT is a constant lattice. */
210 static inline bool
211 ipcp_lat_is_const (struct ipcp_lattice *lat)
213 if (lat->type == IPA_CONST_VALUE)
214 return true;
215 else
216 return false;
219 /* Return whether LAT is a constant lattice that ipa-cp can actually insert
220 into the code (i.e. constants excluding member pointers and pointers). */
221 static inline bool
222 ipcp_lat_is_insertable (struct ipcp_lattice *lat)
224 return lat->type == IPA_CONST_VALUE;
227 /* Return true if LAT1 and LAT2 are equal. */
228 static inline bool
229 ipcp_lats_are_equal (struct ipcp_lattice *lat1, struct ipcp_lattice *lat2)
231 gcc_assert (ipcp_lat_is_const (lat1) && ipcp_lat_is_const (lat2));
232 if (lat1->type != lat2->type)
233 return false;
235 if (TREE_CODE (lat1->constant) == ADDR_EXPR
236 && TREE_CODE (lat2->constant) == ADDR_EXPR
237 && TREE_CODE (TREE_OPERAND (lat1->constant, 0)) == CONST_DECL
238 && TREE_CODE (TREE_OPERAND (lat2->constant, 0)) == CONST_DECL)
239 return operand_equal_p (DECL_INITIAL (TREE_OPERAND (lat1->constant, 0)),
240 DECL_INITIAL (TREE_OPERAND (lat2->constant, 0)), 0);
241 else
242 return operand_equal_p (lat1->constant, lat2->constant, 0);
245 /* Compute Meet arithmetics:
246 Meet (IPA_BOTTOM, x) = IPA_BOTTOM
247 Meet (IPA_TOP,x) = x
248 Meet (const_a,const_b) = IPA_BOTTOM, if const_a != const_b.
249 MEET (const_a,const_b) = const_a, if const_a == const_b.*/
250 static void
251 ipa_lattice_meet (struct ipcp_lattice *res, struct ipcp_lattice *lat1,
252 struct ipcp_lattice *lat2)
254 if (lat1->type == IPA_BOTTOM || lat2->type == IPA_BOTTOM)
256 res->type = IPA_BOTTOM;
257 return;
259 if (lat1->type == IPA_TOP)
261 res->type = lat2->type;
262 res->constant = lat2->constant;
263 return;
265 if (lat2->type == IPA_TOP)
267 res->type = lat1->type;
268 res->constant = lat1->constant;
269 return;
271 if (!ipcp_lats_are_equal (lat1, lat2))
273 res->type = IPA_BOTTOM;
274 return;
276 res->type = lat1->type;
277 res->constant = lat1->constant;
280 /* Return the lattice corresponding to the Ith formal parameter of the function
281 described by INFO. */
282 static inline struct ipcp_lattice *
283 ipcp_get_lattice (struct ipa_node_params *info, int i)
285 return &(info->params[i].ipcp_lattice);
288 /* Given the jump function JFUNC, compute the lattice LAT that describes the
289 value coming down the callsite. INFO describes the caller node so that
290 pass-through jump functions can be evaluated. */
291 static void
292 ipcp_lattice_from_jfunc (struct ipa_node_params *info, struct ipcp_lattice *lat,
293 struct ipa_jump_func *jfunc)
295 if (jfunc->type == IPA_JF_CONST)
297 lat->type = IPA_CONST_VALUE;
298 lat->constant = jfunc->value.constant;
300 else if (jfunc->type == IPA_JF_PASS_THROUGH)
302 struct ipcp_lattice *caller_lat;
303 tree cst;
305 caller_lat = ipcp_get_lattice (info, jfunc->value.pass_through.formal_id);
306 lat->type = caller_lat->type;
307 if (caller_lat->type != IPA_CONST_VALUE)
308 return;
309 cst = caller_lat->constant;
311 if (jfunc->value.pass_through.operation != NOP_EXPR)
313 tree restype;
314 if (TREE_CODE_CLASS (jfunc->value.pass_through.operation)
315 == tcc_comparison)
316 restype = boolean_type_node;
317 else
318 restype = TREE_TYPE (cst);
319 cst = fold_binary (jfunc->value.pass_through.operation,
320 restype, cst, jfunc->value.pass_through.operand);
322 if (!cst || !is_gimple_ip_invariant (cst))
323 lat->type = IPA_BOTTOM;
324 lat->constant = cst;
326 else if (jfunc->type == IPA_JF_ANCESTOR)
328 struct ipcp_lattice *caller_lat;
329 tree t;
331 caller_lat = ipcp_get_lattice (info, jfunc->value.ancestor.formal_id);
332 lat->type = caller_lat->type;
333 if (caller_lat->type != IPA_CONST_VALUE)
334 return;
335 if (TREE_CODE (caller_lat->constant) != ADDR_EXPR)
337 /* This can happen when the constant is a NULL pointer. */
338 lat->type = IPA_BOTTOM;
339 return;
341 t = TREE_OPERAND (caller_lat->constant, 0);
342 t = build_ref_for_offset (EXPR_LOCATION (t), t,
343 jfunc->value.ancestor.offset,
344 jfunc->value.ancestor.type, NULL, false);
345 lat->constant = build_fold_addr_expr (t);
347 else
348 lat->type = IPA_BOTTOM;
351 /* True when OLD_LAT and NEW_LAT values are not the same. */
353 static bool
354 ipcp_lattice_changed (struct ipcp_lattice *old_lat,
355 struct ipcp_lattice *new_lat)
357 if (old_lat->type == new_lat->type)
359 if (!ipcp_lat_is_const (old_lat))
360 return false;
361 if (ipcp_lats_are_equal (old_lat, new_lat))
362 return false;
364 return true;
367 /* Print all ipcp_lattices of all functions to F. */
368 static void
369 ipcp_print_all_lattices (FILE * f)
371 struct cgraph_node *node;
372 int i, count;
374 fprintf (f, "\nLattice:\n");
375 for (node = cgraph_nodes; node; node = node->next)
377 struct ipa_node_params *info;
379 if (!node->analyzed)
380 continue;
381 info = IPA_NODE_REF (node);
382 fprintf (f, " Node: %s:\n", cgraph_node_name (node));
383 count = ipa_get_param_count (info);
384 for (i = 0; i < count; i++)
386 struct ipcp_lattice *lat = ipcp_get_lattice (info, i);
388 fprintf (f, " param [%d]: ", i);
389 if (lat->type == IPA_CONST_VALUE)
391 tree cst = lat->constant;
392 fprintf (f, "type is CONST ");
393 print_generic_expr (f, cst, 0);
394 if (TREE_CODE (cst) == ADDR_EXPR
395 && TREE_CODE (TREE_OPERAND (cst, 0)) == CONST_DECL)
397 fprintf (f, " -> ");
398 print_generic_expr (f, DECL_INITIAL (TREE_OPERAND (cst, 0)),
402 else if (lat->type == IPA_TOP)
403 fprintf (f, "type is TOP");
404 else
405 fprintf (f, "type is BOTTOM");
406 if (ipa_param_cannot_devirtualize_p (info, i))
407 fprintf (f, " - cannot_devirtualize set\n");
408 else if (ipa_param_types_vec_empty (info, i))
409 fprintf (f, " - type list empty\n");
410 else
411 fprintf (f, "\n");
416 /* Return true if ipcp algorithms would allow cloning NODE. */
418 static bool
419 ipcp_versionable_function_p (struct cgraph_node *node)
421 struct cgraph_edge *edge;
423 /* There are a number of generic reasons functions cannot be versioned. We
424 also cannot remove parameters if there are type attributes such as fnspec
425 present. */
426 if (!node->local.versionable
427 || TYPE_ATTRIBUTES (TREE_TYPE (node->decl)))
428 return false;
430 /* Removing arguments doesn't work if the function takes varargs
431 or use __builtin_apply_args. */
432 for (edge = node->callees; edge; edge = edge->next_callee)
434 tree t = edge->callee->decl;
435 if (DECL_BUILT_IN_CLASS (t) == BUILT_IN_NORMAL
436 && (DECL_FUNCTION_CODE (t) == BUILT_IN_APPLY_ARGS
437 || DECL_FUNCTION_CODE (t) == BUILT_IN_VA_START))
438 return false;
441 return true;
444 /* Return true if this NODE is viable candidate for cloning. */
445 static bool
446 ipcp_cloning_candidate_p (struct cgraph_node *node)
448 int n_calls = 0;
449 int n_hot_calls = 0;
450 gcov_type direct_call_sum = 0;
451 struct cgraph_edge *e;
453 /* We never clone functions that are not visible from outside.
454 FIXME: in future we should clone such functions when they are called with
455 different constants, but current ipcp implementation is not good on this.
457 if (cgraph_only_called_directly_p (node) || !node->analyzed)
458 return false;
460 /* When function address is taken, we are pretty sure it will be called in hidden way. */
461 if (node->address_taken)
463 if (dump_file)
464 fprintf (dump_file, "Not considering %s for cloning; address is taken.\n",
465 cgraph_node_name (node));
466 return false;
469 if (cgraph_function_body_availability (node) <= AVAIL_OVERWRITABLE)
471 if (dump_file)
472 fprintf (dump_file, "Not considering %s for cloning; body is overwrittable.\n",
473 cgraph_node_name (node));
474 return false;
476 if (!ipcp_versionable_function_p (node))
478 if (dump_file)
479 fprintf (dump_file, "Not considering %s for cloning; body is not versionable.\n",
480 cgraph_node_name (node));
481 return false;
483 for (e = node->callers; e; e = e->next_caller)
485 direct_call_sum += e->count;
486 n_calls ++;
487 if (cgraph_maybe_hot_edge_p (e))
488 n_hot_calls ++;
491 if (!n_calls)
493 if (dump_file)
494 fprintf (dump_file, "Not considering %s for cloning; no direct calls.\n",
495 cgraph_node_name (node));
496 return false;
498 if (node->local.inline_summary.self_size < n_calls)
500 if (dump_file)
501 fprintf (dump_file, "Considering %s for cloning; code would shrink.\n",
502 cgraph_node_name (node));
503 return true;
506 if (!flag_ipa_cp_clone)
508 if (dump_file)
509 fprintf (dump_file, "Not considering %s for cloning; -fipa-cp-clone disabled.\n",
510 cgraph_node_name (node));
511 return false;
514 if (!optimize_function_for_speed_p (DECL_STRUCT_FUNCTION (node->decl)))
516 if (dump_file)
517 fprintf (dump_file, "Not considering %s for cloning; optimizing it for size.\n",
518 cgraph_node_name (node));
519 return false;
522 /* When profile is available and function is hot, propagate into it even if
523 calls seems cold; constant propagation can improve function's speed
524 significandly. */
525 if (max_count)
527 if (direct_call_sum > node->count * 90 / 100)
529 if (dump_file)
530 fprintf (dump_file, "Considering %s for cloning; usually called directly.\n",
531 cgraph_node_name (node));
532 return true;
535 if (!n_hot_calls)
537 if (dump_file)
538 fprintf (dump_file, "Not considering %s for cloning; no hot calls.\n",
539 cgraph_node_name (node));
540 return false;
542 if (dump_file)
543 fprintf (dump_file, "Considering %s for cloning.\n",
544 cgraph_node_name (node));
545 return true;
548 /* Mark parameter with index I of function described by INFO as unsuitable for
549 devirtualization. Return true if it has already been marked so. */
551 static bool
552 ipa_set_param_cannot_devirtualize (struct ipa_node_params *info, int i)
554 bool ret = info->params[i].cannot_devirtualize;
555 info->params[i].cannot_devirtualize = true;
556 if (info->params[i].types)
557 VEC_free (tree, heap, info->params[i].types);
558 return ret;
561 /* Initialize ipcp_lattices array. The lattices corresponding to supported
562 types (integers, real types and Fortran constants defined as const_decls)
563 are initialized to IPA_TOP, the rest of them to IPA_BOTTOM. */
564 static void
565 ipcp_initialize_node_lattices (struct cgraph_node *node)
567 int i;
568 struct ipa_node_params *info = IPA_NODE_REF (node);
569 enum ipa_lattice_type type;
571 if (ipa_is_called_with_var_arguments (info))
572 type = IPA_BOTTOM;
573 else if (node->local.local)
574 type = IPA_TOP;
575 /* When cloning is allowed, we can assume that externally visible functions
576 are not called. We will compensate this by cloning later. */
577 else if (ipcp_cloning_candidate_p (node))
578 type = IPA_TOP, n_cloning_candidates ++;
579 else
580 type = IPA_BOTTOM;
582 for (i = 0; i < ipa_get_param_count (info) ; i++)
584 ipcp_get_lattice (info, i)->type = type;
585 if (type == IPA_BOTTOM)
586 ipa_set_param_cannot_devirtualize (info, i);
590 /* build INTEGER_CST tree with type TREE_TYPE and value according to LAT.
591 Return the tree. */
592 static tree
593 build_const_val (struct ipcp_lattice *lat, tree tree_type)
595 tree val;
597 gcc_assert (ipcp_lat_is_const (lat));
598 val = lat->constant;
600 if (!useless_type_conversion_p (tree_type, TREE_TYPE (val)))
602 if (fold_convertible_p (tree_type, val))
603 return fold_build1 (NOP_EXPR, tree_type, val);
604 else
605 return fold_build1 (VIEW_CONVERT_EXPR, tree_type, val);
607 return val;
610 /* Compute the proper scale for NODE. It is the ratio between the number of
611 direct calls (represented on the incoming cgraph_edges) and sum of all
612 invocations of NODE (represented as count in cgraph_node).
614 FIXME: This code is wrong. Since the callers can be also clones and
615 the clones are not scaled yet, the sums gets unrealistically high.
616 To properly compute the counts, we would need to do propagation across
617 callgraph (as external call to A might imply call to non-clonned B
618 if A's clone calls clonned B). */
619 static void
620 ipcp_compute_node_scale (struct cgraph_node *node)
622 gcov_type sum;
623 struct cgraph_edge *cs;
625 sum = 0;
626 /* Compute sum of all counts of callers. */
627 for (cs = node->callers; cs != NULL; cs = cs->next_caller)
628 sum += cs->count;
629 /* Work around the unrealistically high sum problem. We just don't want
630 the non-cloned body to have negative or very low frequency. Since
631 majority of execution time will be spent in clones anyway, this should
632 give good enough profile. */
633 if (sum > node->count * 9 / 10)
634 sum = node->count * 9 / 10;
635 if (node->count == 0)
636 ipcp_set_node_scale (node, 0);
637 else
638 ipcp_set_node_scale (node, sum * REG_BR_PROB_BASE / node->count);
641 /* Return true if there are some formal parameters whose value is IPA_TOP (in
642 the whole compilation unit). Change their values to IPA_BOTTOM, since they
643 most probably get their values from outside of this compilation unit. */
644 static bool
645 ipcp_change_tops_to_bottom (void)
647 int i, count;
648 struct cgraph_node *node;
649 bool prop_again;
651 prop_again = false;
652 for (node = cgraph_nodes; node; node = node->next)
654 struct ipa_node_params *info = IPA_NODE_REF (node);
655 count = ipa_get_param_count (info);
656 for (i = 0; i < count; i++)
658 struct ipcp_lattice *lat = ipcp_get_lattice (info, i);
659 if (lat->type == IPA_TOP)
661 prop_again = true;
662 if (dump_file)
664 fprintf (dump_file, "Forcing param ");
665 print_generic_expr (dump_file, ipa_get_param (info, i), 0);
666 fprintf (dump_file, " of node %s to bottom.\n",
667 cgraph_node_name (node));
669 lat->type = IPA_BOTTOM;
671 if (!ipa_param_cannot_devirtualize_p (info, i)
672 && ipa_param_types_vec_empty (info, i))
674 prop_again = true;
675 ipa_set_param_cannot_devirtualize (info, i);
676 if (dump_file)
678 fprintf (dump_file, "Marking param ");
679 print_generic_expr (dump_file, ipa_get_param (info, i), 0);
680 fprintf (dump_file, " of node %s as unusable for "
681 "devirtualization.\n",
682 cgraph_node_name (node));
687 return prop_again;
690 /* Insert BINFO to the list of known types of parameter number I of the
691 function described by CALLEE_INFO. Return true iff the type information
692 associated with the callee parameter changed in any way. */
694 static bool
695 ipcp_add_param_type (struct ipa_node_params *callee_info, int i, tree binfo)
697 int j, count;
699 if (ipa_param_cannot_devirtualize_p (callee_info, i))
700 return false;
702 if (callee_info->params[i].types)
704 count = VEC_length (tree, callee_info->params[i].types);
705 for (j = 0; j < count; j++)
706 if (VEC_index (tree, callee_info->params[i].types, j) == binfo)
707 return false;
710 if (VEC_length (tree, callee_info->params[i].types)
711 == (unsigned) PARAM_VALUE (PARAM_DEVIRT_TYPE_LIST_SIZE))
712 return !ipa_set_param_cannot_devirtualize (callee_info, i);
714 VEC_safe_push (tree, heap, callee_info->params[i].types, binfo);
715 return true;
718 /* Copy known types information for parameter number CALLEE_IDX of CALLEE_INFO
719 from a parameter of CALLER_INFO as described by JF. Return true iff the
720 type information changed in any way. JF must be a pass-through or an
721 ancestor jump function. */
723 static bool
724 ipcp_copy_types (struct ipa_node_params *caller_info,
725 struct ipa_node_params *callee_info,
726 int callee_idx, struct ipa_jump_func *jf)
728 int caller_idx, j, count;
729 bool res;
731 if (ipa_param_cannot_devirtualize_p (callee_info, callee_idx))
732 return false;
734 if (jf->type == IPA_JF_PASS_THROUGH)
736 if (jf->value.pass_through.operation != NOP_EXPR)
738 ipa_set_param_cannot_devirtualize (callee_info, callee_idx);
739 return true;
741 caller_idx = jf->value.pass_through.formal_id;
743 else
744 caller_idx = jf->value.ancestor.formal_id;
746 if (ipa_param_cannot_devirtualize_p (caller_info, caller_idx))
748 ipa_set_param_cannot_devirtualize (callee_info, callee_idx);
749 return true;
752 if (!caller_info->params[caller_idx].types)
753 return false;
755 res = false;
756 count = VEC_length (tree, caller_info->params[caller_idx].types);
757 for (j = 0; j < count; j++)
759 tree binfo = VEC_index (tree, caller_info->params[caller_idx].types, j);
760 if (jf->type == IPA_JF_ANCESTOR)
762 binfo = get_binfo_at_offset (binfo, jf->value.ancestor.offset,
763 jf->value.ancestor.type);
764 if (!binfo)
766 ipa_set_param_cannot_devirtualize (callee_info, callee_idx);
767 return true;
770 res |= ipcp_add_param_type (callee_info, callee_idx, binfo);
772 return res;
775 /* Propagate type information for parameter of CALLEE_INFO number I as
776 described by JF. CALLER_INFO describes the caller. Return true iff the
777 type information changed in any way. */
779 static bool
780 ipcp_propagate_types (struct ipa_node_params *caller_info,
781 struct ipa_node_params *callee_info,
782 struct ipa_jump_func *jf, int i)
784 switch (jf->type)
786 case IPA_JF_UNKNOWN:
787 case IPA_JF_CONST_MEMBER_PTR:
788 case IPA_JF_CONST:
789 break;
791 case IPA_JF_KNOWN_TYPE:
792 return ipcp_add_param_type (callee_info, i, jf->value.base_binfo);
794 case IPA_JF_PASS_THROUGH:
795 case IPA_JF_ANCESTOR:
796 return ipcp_copy_types (caller_info, callee_info, i, jf);
799 /* If we reach this we cannot use this parameter for devirtualization. */
800 return !ipa_set_param_cannot_devirtualize (callee_info, i);
803 /* Interprocedural analysis. The algorithm propagates constants from the
804 caller's parameters to the callee's arguments. */
805 static void
806 ipcp_propagate_stage (void)
808 int i;
809 struct ipcp_lattice inc_lat = { IPA_BOTTOM, NULL };
810 struct ipcp_lattice new_lat = { IPA_BOTTOM, NULL };
811 struct ipcp_lattice *dest_lat;
812 struct cgraph_edge *cs;
813 struct ipa_jump_func *jump_func;
814 struct ipa_func_list *wl;
815 int count;
817 ipa_check_create_node_params ();
818 ipa_check_create_edge_args ();
820 /* Initialize worklist to contain all functions. */
821 wl = ipa_init_func_list ();
822 while (wl)
824 struct cgraph_node *node = ipa_pop_func_from_list (&wl);
825 struct ipa_node_params *info = IPA_NODE_REF (node);
827 for (cs = node->callees; cs; cs = cs->next_callee)
829 struct ipa_node_params *callee_info = IPA_NODE_REF (cs->callee);
830 struct ipa_edge_args *args = IPA_EDGE_REF (cs);
832 if (ipa_is_called_with_var_arguments (callee_info)
833 || !cs->callee->analyzed
834 || ipa_is_called_with_var_arguments (callee_info))
835 continue;
837 count = ipa_get_cs_argument_count (args);
838 for (i = 0; i < count; i++)
840 jump_func = ipa_get_ith_jump_func (args, i);
841 ipcp_lattice_from_jfunc (info, &inc_lat, jump_func);
842 dest_lat = ipcp_get_lattice (callee_info, i);
843 ipa_lattice_meet (&new_lat, &inc_lat, dest_lat);
844 if (ipcp_lattice_changed (&new_lat, dest_lat))
846 dest_lat->type = new_lat.type;
847 dest_lat->constant = new_lat.constant;
848 ipa_push_func_to_list (&wl, cs->callee);
851 if (ipcp_propagate_types (info, callee_info, jump_func, i))
852 ipa_push_func_to_list (&wl, cs->callee);
858 /* Call the constant propagation algorithm and re-call it if necessary
859 (if there are undetermined values left). */
860 static void
861 ipcp_iterate_stage (void)
863 struct cgraph_node *node;
864 n_cloning_candidates = 0;
866 if (dump_file)
867 fprintf (dump_file, "\nIPA iterate stage:\n\n");
869 if (in_lto_p)
870 ipa_update_after_lto_read ();
872 for (node = cgraph_nodes; node; node = node->next)
874 ipcp_initialize_node_lattices (node);
875 ipcp_compute_node_scale (node);
877 if (dump_file && (dump_flags & TDF_DETAILS))
879 ipcp_print_all_lattices (dump_file);
880 ipcp_function_scale_print (dump_file);
883 ipcp_propagate_stage ();
884 if (ipcp_change_tops_to_bottom ())
885 /* Some lattices have changed from IPA_TOP to IPA_BOTTOM.
886 This change should be propagated. */
888 gcc_assert (n_cloning_candidates);
889 ipcp_propagate_stage ();
891 if (dump_file)
893 fprintf (dump_file, "\nIPA lattices after propagation:\n");
894 ipcp_print_all_lattices (dump_file);
895 if (dump_flags & TDF_DETAILS)
896 ipcp_print_profile_data (dump_file);
900 /* Check conditions to forbid constant insertion to function described by
901 NODE. */
902 static inline bool
903 ipcp_node_modifiable_p (struct cgraph_node *node)
905 /* Once we will be able to do in-place replacement, we can be more
906 lax here. */
907 return ipcp_versionable_function_p (node);
910 /* Print count scale data structures. */
911 static void
912 ipcp_function_scale_print (FILE * f)
914 struct cgraph_node *node;
916 for (node = cgraph_nodes; node; node = node->next)
918 if (!node->analyzed)
919 continue;
920 fprintf (f, "printing scale for %s: ", cgraph_node_name (node));
921 fprintf (f, "value is " HOST_WIDE_INT_PRINT_DEC
922 " \n", (HOST_WIDE_INT) ipcp_get_node_scale (node));
926 /* Print counts of all cgraph nodes. */
927 static void
928 ipcp_print_func_profile_counts (FILE * f)
930 struct cgraph_node *node;
932 for (node = cgraph_nodes; node; node = node->next)
934 fprintf (f, "function %s: ", cgraph_node_name (node));
935 fprintf (f, "count is " HOST_WIDE_INT_PRINT_DEC
936 " \n", (HOST_WIDE_INT) node->count);
940 /* Print counts of all cgraph edges. */
941 static void
942 ipcp_print_call_profile_counts (FILE * f)
944 struct cgraph_node *node;
945 struct cgraph_edge *cs;
947 for (node = cgraph_nodes; node; node = node->next)
949 for (cs = node->callees; cs; cs = cs->next_callee)
951 fprintf (f, "%s -> %s ", cgraph_node_name (cs->caller),
952 cgraph_node_name (cs->callee));
953 fprintf (f, "count is " HOST_WIDE_INT_PRINT_DEC " \n",
954 (HOST_WIDE_INT) cs->count);
959 /* Print profile info for all functions. */
960 static void
961 ipcp_print_profile_data (FILE * f)
963 fprintf (f, "\nNODE COUNTS :\n");
964 ipcp_print_func_profile_counts (f);
965 fprintf (f, "\nCS COUNTS stage:\n");
966 ipcp_print_call_profile_counts (f);
969 /* Build and initialize ipa_replace_map struct according to LAT. This struct is
970 processed by versioning, which operates according to the flags set.
971 PARM_TREE is the formal parameter found to be constant. LAT represents the
972 constant. */
973 static struct ipa_replace_map *
974 ipcp_create_replace_map (tree parm_tree, struct ipcp_lattice *lat)
976 struct ipa_replace_map *replace_map;
977 tree const_val;
979 replace_map = ggc_alloc_ipa_replace_map ();
980 const_val = build_const_val (lat, TREE_TYPE (parm_tree));
981 if (dump_file)
983 fprintf (dump_file, " replacing param ");
984 print_generic_expr (dump_file, parm_tree, 0);
985 fprintf (dump_file, " with const ");
986 print_generic_expr (dump_file, const_val, 0);
987 fprintf (dump_file, "\n");
989 replace_map->old_tree = parm_tree;
990 replace_map->new_tree = const_val;
991 replace_map->replace_p = true;
992 replace_map->ref_p = false;
994 return replace_map;
997 /* Return true if this callsite should be redirected to the original callee
998 (instead of the cloned one). */
999 static bool
1000 ipcp_need_redirect_p (struct cgraph_edge *cs)
1002 struct ipa_node_params *orig_callee_info;
1003 int i, count;
1004 struct cgraph_node *node = cs->callee, *orig;
1006 if (!n_cloning_candidates)
1007 return false;
1009 if ((orig = ipcp_get_orig_node (node)) != NULL)
1010 node = orig;
1011 if (ipcp_get_orig_node (cs->caller))
1012 return false;
1014 orig_callee_info = IPA_NODE_REF (node);
1015 count = ipa_get_param_count (orig_callee_info);
1016 for (i = 0; i < count; i++)
1018 struct ipcp_lattice *lat = ipcp_get_lattice (orig_callee_info, i);
1019 struct ipa_jump_func *jump_func;
1021 jump_func = ipa_get_ith_jump_func (IPA_EDGE_REF (cs), i);
1022 if ((ipcp_lat_is_const (lat)
1023 && jump_func->type != IPA_JF_CONST)
1024 || (!ipa_param_cannot_devirtualize_p (orig_callee_info, i)
1025 && !ipa_param_types_vec_empty (orig_callee_info, i)
1026 && jump_func->type != IPA_JF_CONST
1027 && jump_func->type != IPA_JF_KNOWN_TYPE))
1028 return true;
1031 return false;
1034 /* Fix the callsites and the call graph after function cloning was done. */
1035 static void
1036 ipcp_update_callgraph (void)
1038 struct cgraph_node *node;
1040 for (node = cgraph_nodes; node; node = node->next)
1041 if (node->analyzed && ipcp_node_is_clone (node))
1043 bitmap args_to_skip = BITMAP_ALLOC (NULL);
1044 struct cgraph_node *orig_node = ipcp_get_orig_node (node);
1045 struct ipa_node_params *info = IPA_NODE_REF (orig_node);
1046 int i, count = ipa_get_param_count (info);
1047 struct cgraph_edge *cs, *next;
1049 for (i = 0; i < count; i++)
1051 struct ipcp_lattice *lat = ipcp_get_lattice (info, i);
1053 /* We can proactively remove obviously unused arguments. */
1054 if (!ipa_is_param_used (info, i))
1056 bitmap_set_bit (args_to_skip, i);
1057 continue;
1060 if (lat->type == IPA_CONST_VALUE)
1061 bitmap_set_bit (args_to_skip, i);
1063 for (cs = node->callers; cs; cs = next)
1065 next = cs->next_caller;
1066 if (!ipcp_node_is_clone (cs->caller) && ipcp_need_redirect_p (cs))
1068 if (dump_file)
1069 fprintf (dump_file, "Redirecting edge %s/%i -> %s/%i "
1070 "back to %s/%i.",
1071 cgraph_node_name (cs->caller), cs->caller->uid,
1072 cgraph_node_name (cs->callee), cs->callee->uid,
1073 cgraph_node_name (orig_node), orig_node->uid);
1074 cgraph_redirect_edge_callee (cs, orig_node);
1080 /* Update profiling info for versioned functions and the functions they were
1081 versioned from. */
1082 static void
1083 ipcp_update_profiling (void)
1085 struct cgraph_node *node, *orig_node;
1086 gcov_type scale, scale_complement;
1087 struct cgraph_edge *cs;
1089 for (node = cgraph_nodes; node; node = node->next)
1091 if (ipcp_node_is_clone (node))
1093 orig_node = ipcp_get_orig_node (node);
1094 scale = ipcp_get_node_scale (orig_node);
1095 node->count = orig_node->count * scale / REG_BR_PROB_BASE;
1096 scale_complement = REG_BR_PROB_BASE - scale;
1097 orig_node->count =
1098 orig_node->count * scale_complement / REG_BR_PROB_BASE;
1099 for (cs = node->callees; cs; cs = cs->next_callee)
1100 cs->count = cs->count * scale / REG_BR_PROB_BASE;
1101 for (cs = orig_node->callees; cs; cs = cs->next_callee)
1102 cs->count = cs->count * scale_complement / REG_BR_PROB_BASE;
1107 /* If NODE was cloned, how much would program grow? */
1108 static long
1109 ipcp_estimate_growth (struct cgraph_node *node)
1111 struct cgraph_edge *cs;
1112 int redirectable_node_callers = 0;
1113 int removable_args = 0;
1114 bool need_original
1115 = !cgraph_will_be_removed_from_program_if_no_direct_calls (node);
1116 struct ipa_node_params *info;
1117 int i, count;
1118 int growth;
1120 for (cs = node->callers; cs != NULL; cs = cs->next_caller)
1121 if (cs->caller == node || !ipcp_need_redirect_p (cs))
1122 redirectable_node_callers++;
1123 else
1124 need_original = true;
1126 /* If we will be able to fully replace orignal node, we never increase
1127 program size. */
1128 if (!need_original)
1129 return 0;
1131 info = IPA_NODE_REF (node);
1132 count = ipa_get_param_count (info);
1133 for (i = 0; i < count; i++)
1135 struct ipcp_lattice *lat = ipcp_get_lattice (info, i);
1137 /* We can proactively remove obviously unused arguments. */
1138 if (!ipa_is_param_used (info, i))
1139 removable_args++;
1141 if (lat->type == IPA_CONST_VALUE)
1142 removable_args++;
1145 /* We make just very simple estimate of savings for removal of operand from
1146 call site. Precise cost is dificult to get, as our size metric counts
1147 constants and moves as free. Generally we are looking for cases that
1148 small function is called very many times. */
1149 growth = node->local.inline_summary.self_size
1150 - removable_args * redirectable_node_callers;
1151 if (growth < 0)
1152 return 0;
1153 return growth;
1157 /* Estimate cost of cloning NODE. */
1158 static long
1159 ipcp_estimate_cloning_cost (struct cgraph_node *node)
1161 int freq_sum = 1;
1162 gcov_type count_sum = 1;
1163 struct cgraph_edge *e;
1164 int cost;
1166 cost = ipcp_estimate_growth (node) * 1000;
1167 if (!cost)
1169 if (dump_file)
1170 fprintf (dump_file, "Versioning of %s will save code size\n",
1171 cgraph_node_name (node));
1172 return 0;
1175 for (e = node->callers; e; e = e->next_caller)
1176 if (!bitmap_bit_p (dead_nodes, e->caller->uid)
1177 && !ipcp_need_redirect_p (e))
1179 count_sum += e->count;
1180 freq_sum += e->frequency + 1;
1183 if (max_count)
1184 cost /= count_sum * 1000 / max_count + 1;
1185 else
1186 cost /= freq_sum * 1000 / REG_BR_PROB_BASE + 1;
1187 if (dump_file)
1188 fprintf (dump_file, "Cost of versioning %s is %i, (size: %i, freq: %i)\n",
1189 cgraph_node_name (node), cost, node->local.inline_summary.self_size,
1190 freq_sum);
1191 return cost + 1;
1194 /* Walk indirect calls of NODE and if any polymorphic can be turned into a
1195 direct one now, do so. */
1197 static void
1198 ipcp_process_devirtualization_opportunities (struct cgraph_node *node)
1200 struct ipa_node_params *info = IPA_NODE_REF (node);
1201 struct cgraph_edge *ie, *next_ie;
1203 for (ie = node->indirect_calls; ie; ie = next_ie)
1205 int param_index, types_count, j;
1206 HOST_WIDE_INT token;
1207 tree target, delta;
1209 next_ie = ie->next_callee;
1210 if (!ie->indirect_info->polymorphic)
1211 continue;
1212 param_index = ie->indirect_info->param_index;
1213 if (param_index == -1
1214 || ipa_param_cannot_devirtualize_p (info, param_index)
1215 || ipa_param_types_vec_empty (info, param_index))
1216 continue;
1218 token = ie->indirect_info->otr_token;
1219 target = NULL_TREE;
1220 types_count = VEC_length (tree, info->params[param_index].types);
1221 for (j = 0; j < types_count; j++)
1223 tree binfo = VEC_index (tree, info->params[param_index].types, j);
1224 tree d;
1225 tree t = gimple_get_virt_mehtod_for_binfo (token, binfo, &d, true);
1227 if (!t)
1229 target = NULL_TREE;
1230 break;
1232 else if (!target)
1234 target = t;
1235 delta = d;
1237 else if (target != t || !tree_int_cst_equal (delta, d))
1239 target = NULL_TREE;
1240 break;
1244 if (target)
1245 ipa_make_edge_direct_to_target (ie, target, delta);
1249 /* Return number of live constant parameters. */
1250 static int
1251 ipcp_const_param_count (struct cgraph_node *node)
1253 int const_param = 0;
1254 struct ipa_node_params *info = IPA_NODE_REF (node);
1255 int count = ipa_get_param_count (info);
1256 int i;
1258 for (i = 0; i < count; i++)
1260 struct ipcp_lattice *lat = ipcp_get_lattice (info, i);
1261 if ((ipcp_lat_is_insertable (lat)
1262 /* Do not count obviously unused arguments. */
1263 && ipa_is_param_used (info, i))
1264 || (!ipa_param_cannot_devirtualize_p (info, i)
1265 && !ipa_param_types_vec_empty (info, i)))
1266 const_param++;
1268 return const_param;
1271 /* Given that a formal parameter of NODE given by INDEX is known to be constant
1272 CST, try to find any indirect edges that can be made direct and make them
1273 so. Note that INDEX is the number the parameter at the time of analyzing
1274 parameter uses and parameter removals should not be considered for it. (In
1275 fact, the parameter itself has just been removed.) */
1277 static void
1278 ipcp_discover_new_direct_edges (struct cgraph_node *node, int index, tree cst)
1280 struct cgraph_edge *ie, *next_ie;
1282 for (ie = node->indirect_calls; ie; ie = next_ie)
1284 struct cgraph_indirect_call_info *ici = ie->indirect_info;
1286 next_ie = ie->next_callee;
1287 if (ici->param_index != index
1288 || ici->polymorphic)
1289 continue;
1291 ipa_make_edge_direct_to_target (ie, cst, NULL_TREE);
1296 /* Propagate the constant parameters found by ipcp_iterate_stage()
1297 to the function's code. */
1298 static void
1299 ipcp_insert_stage (void)
1301 struct cgraph_node *node, *node1 = NULL;
1302 int i;
1303 VEC (cgraph_edge_p, heap) * redirect_callers;
1304 VEC (ipa_replace_map_p,gc)* replace_trees;
1305 int node_callers, count;
1306 tree parm_tree;
1307 struct ipa_replace_map *replace_param;
1308 fibheap_t heap;
1309 long overall_size = 0, new_size = 0;
1310 long max_new_size;
1312 ipa_check_create_node_params ();
1313 ipa_check_create_edge_args ();
1314 if (dump_file)
1315 fprintf (dump_file, "\nIPA insert stage:\n\n");
1317 dead_nodes = BITMAP_ALLOC (NULL);
1319 for (node = cgraph_nodes; node; node = node->next)
1320 if (node->analyzed)
1322 if (node->count > max_count)
1323 max_count = node->count;
1324 overall_size += node->local.inline_summary.self_size;
1327 max_new_size = overall_size;
1328 if (max_new_size < PARAM_VALUE (PARAM_LARGE_UNIT_INSNS))
1329 max_new_size = PARAM_VALUE (PARAM_LARGE_UNIT_INSNS);
1330 max_new_size = max_new_size * PARAM_VALUE (PARAM_IPCP_UNIT_GROWTH) / 100 + 1;
1332 /* First collect all functions we proved to have constant arguments to
1333 heap. */
1334 heap = fibheap_new ();
1335 for (node = cgraph_nodes; node; node = node->next)
1337 struct ipa_node_params *info;
1338 /* Propagation of the constant is forbidden in certain conditions. */
1339 if (!node->analyzed || !ipcp_node_modifiable_p (node))
1340 continue;
1341 info = IPA_NODE_REF (node);
1342 if (ipa_is_called_with_var_arguments (info))
1343 continue;
1344 if (ipcp_const_param_count (node))
1345 node->aux = fibheap_insert (heap, ipcp_estimate_cloning_cost (node),
1346 node);
1349 /* Now clone in priority order until code size growth limits are met or
1350 heap is emptied. */
1351 while (!fibheap_empty (heap))
1353 struct ipa_node_params *info;
1354 int growth = 0;
1355 bitmap args_to_skip;
1356 struct cgraph_edge *cs;
1358 node = (struct cgraph_node *)fibheap_extract_min (heap);
1359 node->aux = NULL;
1360 if (dump_file)
1361 fprintf (dump_file, "considering function %s\n",
1362 cgraph_node_name (node));
1364 growth = ipcp_estimate_growth (node);
1366 if (new_size + growth > max_new_size)
1367 break;
1368 if (growth
1369 && optimize_function_for_size_p (DECL_STRUCT_FUNCTION (node->decl)))
1371 if (dump_file)
1372 fprintf (dump_file, "Not versioning, cold code would grow");
1373 continue;
1376 new_size += growth;
1378 /* Look if original function becomes dead after clonning. */
1379 for (cs = node->callers; cs != NULL; cs = cs->next_caller)
1380 if (cs->caller == node || ipcp_need_redirect_p (cs))
1381 break;
1382 if (!cs && cgraph_will_be_removed_from_program_if_no_direct_calls (node))
1383 bitmap_set_bit (dead_nodes, node->uid);
1385 info = IPA_NODE_REF (node);
1386 count = ipa_get_param_count (info);
1388 replace_trees = VEC_alloc (ipa_replace_map_p, gc, 1);
1389 args_to_skip = BITMAP_GGC_ALLOC ();
1390 for (i = 0; i < count; i++)
1392 struct ipcp_lattice *lat = ipcp_get_lattice (info, i);
1393 parm_tree = ipa_get_param (info, i);
1395 /* We can proactively remove obviously unused arguments. */
1396 if (!ipa_is_param_used (info, i))
1398 bitmap_set_bit (args_to_skip, i);
1399 continue;
1402 if (lat->type == IPA_CONST_VALUE)
1404 replace_param =
1405 ipcp_create_replace_map (parm_tree, lat);
1406 VEC_safe_push (ipa_replace_map_p, gc, replace_trees, replace_param);
1407 bitmap_set_bit (args_to_skip, i);
1411 /* Compute how many callers node has. */
1412 node_callers = 0;
1413 for (cs = node->callers; cs != NULL; cs = cs->next_caller)
1414 node_callers++;
1415 redirect_callers = VEC_alloc (cgraph_edge_p, heap, node_callers);
1416 for (cs = node->callers; cs != NULL; cs = cs->next_caller)
1417 if (!cs->indirect_inlining_edge)
1418 VEC_quick_push (cgraph_edge_p, redirect_callers, cs);
1420 /* Redirecting all the callers of the node to the
1421 new versioned node. */
1422 node1 =
1423 cgraph_create_virtual_clone (node, redirect_callers, replace_trees,
1424 args_to_skip, "constprop");
1425 args_to_skip = NULL;
1426 VEC_free (cgraph_edge_p, heap, redirect_callers);
1427 replace_trees = NULL;
1429 if (node1 == NULL)
1430 continue;
1431 ipcp_process_devirtualization_opportunities (node1);
1433 if (dump_file)
1434 fprintf (dump_file, "versioned function %s with growth %i, overall %i\n",
1435 cgraph_node_name (node), (int)growth, (int)new_size);
1436 ipcp_init_cloned_node (node, node1);
1438 info = IPA_NODE_REF (node);
1439 for (i = 0; i < count; i++)
1441 struct ipcp_lattice *lat = ipcp_get_lattice (info, i);
1442 if (lat->type == IPA_CONST_VALUE)
1443 ipcp_discover_new_direct_edges (node1, i, lat->constant);
1446 if (dump_file)
1447 dump_function_to_file (node1->decl, dump_file, dump_flags);
1449 for (cs = node->callees; cs; cs = cs->next_callee)
1450 if (cs->callee->aux)
1452 fibheap_delete_node (heap, (fibnode_t) cs->callee->aux);
1453 cs->callee->aux = fibheap_insert (heap,
1454 ipcp_estimate_cloning_cost (cs->callee),
1455 cs->callee);
1459 while (!fibheap_empty (heap))
1461 if (dump_file)
1462 fprintf (dump_file, "skipping function %s\n",
1463 cgraph_node_name (node));
1464 node = (struct cgraph_node *) fibheap_extract_min (heap);
1465 node->aux = NULL;
1467 fibheap_delete (heap);
1468 BITMAP_FREE (dead_nodes);
1469 ipcp_update_callgraph ();
1470 ipcp_update_profiling ();
1473 /* The IPCP driver. */
1474 static unsigned int
1475 ipcp_driver (void)
1477 cgraph_remove_unreachable_nodes (true,dump_file);
1478 if (dump_file)
1480 fprintf (dump_file, "\nIPA structures before propagation:\n");
1481 if (dump_flags & TDF_DETAILS)
1482 ipa_print_all_params (dump_file);
1483 ipa_print_all_jump_functions (dump_file);
1485 /* 2. Do the interprocedural propagation. */
1486 ipcp_iterate_stage ();
1487 /* 3. Insert the constants found to the functions. */
1488 ipcp_insert_stage ();
1489 if (dump_file && (dump_flags & TDF_DETAILS))
1491 fprintf (dump_file, "\nProfiling info after insert stage:\n");
1492 ipcp_print_profile_data (dump_file);
1494 /* Free all IPCP structures. */
1495 ipa_free_all_structures_after_ipa_cp ();
1496 if (dump_file)
1497 fprintf (dump_file, "\nIPA constant propagation end\n");
1498 return 0;
1501 /* Initialization and computation of IPCP data structures. This is the initial
1502 intraprocedural analysis of functions, which gathers information to be
1503 propagated later on. */
1505 static void
1506 ipcp_generate_summary (void)
1508 struct cgraph_node *node;
1510 if (dump_file)
1511 fprintf (dump_file, "\nIPA constant propagation start:\n");
1512 ipa_check_create_node_params ();
1513 ipa_check_create_edge_args ();
1514 ipa_register_cgraph_hooks ();
1516 for (node = cgraph_nodes; node; node = node->next)
1517 if (node->analyzed)
1519 /* Unreachable nodes should have been eliminated before ipcp. */
1520 gcc_assert (node->needed || node->reachable);
1522 node->local.versionable = tree_versionable_function_p (node->decl);
1523 ipa_analyze_node (node);
1527 /* Write ipcp summary for nodes in SET. */
1528 static void
1529 ipcp_write_summary (cgraph_node_set set,
1530 varpool_node_set vset ATTRIBUTE_UNUSED)
1532 ipa_prop_write_jump_functions (set);
1535 /* Read ipcp summary. */
1536 static void
1537 ipcp_read_summary (void)
1539 ipa_prop_read_jump_functions ();
1542 /* Gate for IPCP optimization. */
1543 static bool
1544 cgraph_gate_cp (void)
1546 /* FIXME: We should remove the optimize check after we ensure we never run
1547 IPA passes when not optimizng. */
1548 return flag_ipa_cp && optimize;
1551 struct ipa_opt_pass_d pass_ipa_cp =
1554 IPA_PASS,
1555 "cp", /* name */
1556 cgraph_gate_cp, /* gate */
1557 ipcp_driver, /* execute */
1558 NULL, /* sub */
1559 NULL, /* next */
1560 0, /* static_pass_number */
1561 TV_IPA_CONSTANT_PROP, /* tv_id */
1562 0, /* properties_required */
1563 0, /* properties_provided */
1564 0, /* properties_destroyed */
1565 0, /* todo_flags_start */
1566 TODO_dump_cgraph | TODO_dump_func |
1567 TODO_remove_functions | TODO_ggc_collect /* todo_flags_finish */
1569 ipcp_generate_summary, /* generate_summary */
1570 ipcp_write_summary, /* write_summary */
1571 ipcp_read_summary, /* read_summary */
1572 NULL, /* write_optimization_summary */
1573 NULL, /* read_optimization_summary */
1574 NULL, /* stmt_fixup */
1575 0, /* TODOs */
1576 NULL, /* function_transform */
1577 NULL, /* variable_transform */