target-supports.exp (check_effective_target_weak_undefined): Return 0 on hppa*-*...
[official-gcc.git] / gcc / ipa-inline.c
blob360c3de3289095971f344508e8d84d50fe8313b0
1 /* Inlining decision heuristics.
2 Copyright (C) 2003-2019 Free Software Foundation, Inc.
3 Contributed by Jan Hubicka
5 This file is part of GCC.
7 GCC is free software; you can redistribute it and/or modify it under
8 the terms of the GNU General Public License as published by the Free
9 Software Foundation; either version 3, or (at your option) any later
10 version.
12 GCC is distributed in the hope that it will be useful, but WITHOUT ANY
13 WARRANTY; without even the implied warranty of MERCHANTABILITY or
14 FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
15 for more details.
17 You should have received a copy of the GNU General Public License
18 along with GCC; see the file COPYING3. If not see
19 <http://www.gnu.org/licenses/>. */
21 /* Inlining decision heuristics
23 The implementation of inliner is organized as follows:
25 inlining heuristics limits
27 can_inline_edge_p allow to check that particular inlining is allowed
28 by the limits specified by user (allowed function growth, growth and so
29 on).
31 Functions are inlined when it is obvious the result is profitable (such
32 as functions called once or when inlining reduce code size).
33 In addition to that we perform inlining of small functions and recursive
34 inlining.
36 inlining heuristics
38 The inliner itself is split into two passes:
40 pass_early_inlining
42 Simple local inlining pass inlining callees into current function.
43 This pass makes no use of whole unit analysis and thus it can do only
44 very simple decisions based on local properties.
46 The strength of the pass is that it is run in topological order
47 (reverse postorder) on the callgraph. Functions are converted into SSA
48 form just before this pass and optimized subsequently. As a result, the
49 callees of the function seen by the early inliner was already optimized
50 and results of early inlining adds a lot of optimization opportunities
51 for the local optimization.
53 The pass handle the obvious inlining decisions within the compilation
54 unit - inlining auto inline functions, inlining for size and
55 flattening.
57 main strength of the pass is the ability to eliminate abstraction
58 penalty in C++ code (via combination of inlining and early
59 optimization) and thus improve quality of analysis done by real IPA
60 optimizers.
62 Because of lack of whole unit knowledge, the pass cannot really make
63 good code size/performance tradeoffs. It however does very simple
64 speculative inlining allowing code size to grow by
65 EARLY_INLINING_INSNS when callee is leaf function. In this case the
66 optimizations performed later are very likely to eliminate the cost.
68 pass_ipa_inline
70 This is the real inliner able to handle inlining with whole program
71 knowledge. It performs following steps:
73 1) inlining of small functions. This is implemented by greedy
74 algorithm ordering all inlinable cgraph edges by their badness and
75 inlining them in this order as long as inline limits allows doing so.
77 This heuristics is not very good on inlining recursive calls. Recursive
78 calls can be inlined with results similar to loop unrolling. To do so,
79 special purpose recursive inliner is executed on function when
80 recursive edge is met as viable candidate.
82 2) Unreachable functions are removed from callgraph. Inlining leads
83 to devirtualization and other modification of callgraph so functions
84 may become unreachable during the process. Also functions declared as
85 extern inline or virtual functions are removed, since after inlining
86 we no longer need the offline bodies.
88 3) Functions called once and not exported from the unit are inlined.
89 This should almost always lead to reduction of code size by eliminating
90 the need for offline copy of the function. */
92 #include "config.h"
93 #include "system.h"
94 #include "coretypes.h"
95 #include "backend.h"
96 #include "target.h"
97 #include "rtl.h"
98 #include "tree.h"
99 #include "gimple.h"
100 #include "alloc-pool.h"
101 #include "tree-pass.h"
102 #include "gimple-ssa.h"
103 #include "cgraph.h"
104 #include "lto-streamer.h"
105 #include "trans-mem.h"
106 #include "calls.h"
107 #include "tree-inline.h"
108 #include "params.h"
109 #include "profile.h"
110 #include "symbol-summary.h"
111 #include "tree-vrp.h"
112 #include "ipa-prop.h"
113 #include "ipa-fnsummary.h"
114 #include "ipa-inline.h"
115 #include "ipa-utils.h"
116 #include "sreal.h"
117 #include "auto-profile.h"
118 #include "builtins.h"
119 #include "fibonacci_heap.h"
120 #include "stringpool.h"
121 #include "attribs.h"
122 #include "asan.h"
124 typedef fibonacci_heap <sreal, cgraph_edge> edge_heap_t;
125 typedef fibonacci_node <sreal, cgraph_edge> edge_heap_node_t;
127 /* Statistics we collect about inlining algorithm. */
128 static int overall_size;
129 static profile_count max_count;
130 static profile_count spec_rem;
132 /* Return false when inlining edge E would lead to violating
133 limits on function unit growth or stack usage growth.
135 The relative function body growth limit is present generally
136 to avoid problems with non-linear behavior of the compiler.
137 To allow inlining huge functions into tiny wrapper, the limit
138 is always based on the bigger of the two functions considered.
140 For stack growth limits we always base the growth in stack usage
141 of the callers. We want to prevent applications from segfaulting
142 on stack overflow when functions with huge stack frames gets
143 inlined. */
145 static bool
146 caller_growth_limits (struct cgraph_edge *e)
148 struct cgraph_node *to = e->caller;
149 struct cgraph_node *what = e->callee->ultimate_alias_target ();
150 int newsize;
151 int limit = 0;
152 HOST_WIDE_INT stack_size_limit = 0, inlined_stack;
153 ipa_fn_summary *info, *what_info;
154 ipa_fn_summary *outer_info = ipa_fn_summaries->get (to);
156 /* Look for function e->caller is inlined to. While doing
157 so work out the largest function body on the way. As
158 described above, we want to base our function growth
159 limits based on that. Not on the self size of the
160 outer function, not on the self size of inline code
161 we immediately inline to. This is the most relaxed
162 interpretation of the rule "do not grow large functions
163 too much in order to prevent compiler from exploding". */
164 while (true)
166 info = ipa_fn_summaries->get (to);
167 if (limit < info->self_size)
168 limit = info->self_size;
169 if (stack_size_limit < info->estimated_self_stack_size)
170 stack_size_limit = info->estimated_self_stack_size;
171 if (to->global.inlined_to)
172 to = to->callers->caller;
173 else
174 break;
177 what_info = ipa_fn_summaries->get (what);
179 if (limit < what_info->self_size)
180 limit = what_info->self_size;
182 limit += limit * PARAM_VALUE (PARAM_LARGE_FUNCTION_GROWTH) / 100;
184 /* Check the size after inlining against the function limits. But allow
185 the function to shrink if it went over the limits by forced inlining. */
186 newsize = estimate_size_after_inlining (to, e);
187 if (newsize >= info->size
188 && newsize > PARAM_VALUE (PARAM_LARGE_FUNCTION_INSNS)
189 && newsize > limit)
191 e->inline_failed = CIF_LARGE_FUNCTION_GROWTH_LIMIT;
192 return false;
195 if (!what_info->estimated_stack_size)
196 return true;
198 /* FIXME: Stack size limit often prevents inlining in Fortran programs
199 due to large i/o datastructures used by the Fortran front-end.
200 We ought to ignore this limit when we know that the edge is executed
201 on every invocation of the caller (i.e. its call statement dominates
202 exit block). We do not track this information, yet. */
203 stack_size_limit += ((gcov_type)stack_size_limit
204 * PARAM_VALUE (PARAM_STACK_FRAME_GROWTH) / 100);
206 inlined_stack = (outer_info->stack_frame_offset
207 + outer_info->estimated_self_stack_size
208 + what_info->estimated_stack_size);
209 /* Check new stack consumption with stack consumption at the place
210 stack is used. */
211 if (inlined_stack > stack_size_limit
212 /* If function already has large stack usage from sibling
213 inline call, we can inline, too.
214 This bit overoptimistically assume that we are good at stack
215 packing. */
216 && inlined_stack > info->estimated_stack_size
217 && inlined_stack > PARAM_VALUE (PARAM_LARGE_STACK_FRAME))
219 e->inline_failed = CIF_LARGE_STACK_FRAME_GROWTH_LIMIT;
220 return false;
222 return true;
225 /* Dump info about why inlining has failed. */
227 static void
228 report_inline_failed_reason (struct cgraph_edge *e)
230 if (dump_enabled_p ())
232 dump_printf_loc (MSG_MISSED_OPTIMIZATION, e->call_stmt,
233 " not inlinable: %C -> %C, %s\n",
234 e->caller, e->callee,
235 cgraph_inline_failed_string (e->inline_failed));
236 if ((e->inline_failed == CIF_TARGET_OPTION_MISMATCH
237 || e->inline_failed == CIF_OPTIMIZATION_MISMATCH)
238 && e->caller->lto_file_data
239 && e->callee->ultimate_alias_target ()->lto_file_data)
241 dump_printf_loc (MSG_MISSED_OPTIMIZATION, e->call_stmt,
242 " LTO objects: %s, %s\n",
243 e->caller->lto_file_data->file_name,
244 e->callee->ultimate_alias_target ()->lto_file_data->file_name);
246 if (e->inline_failed == CIF_TARGET_OPTION_MISMATCH)
247 if (dump_file)
248 cl_target_option_print_diff
249 (dump_file, 2, target_opts_for_fn (e->caller->decl),
250 target_opts_for_fn (e->callee->ultimate_alias_target ()->decl));
251 if (e->inline_failed == CIF_OPTIMIZATION_MISMATCH)
252 if (dump_file)
253 cl_optimization_print_diff
254 (dump_file, 2, opts_for_fn (e->caller->decl),
255 opts_for_fn (e->callee->ultimate_alias_target ()->decl));
259 /* Decide whether sanitizer-related attributes allow inlining. */
261 static bool
262 sanitize_attrs_match_for_inline_p (const_tree caller, const_tree callee)
264 if (!caller || !callee)
265 return true;
267 /* Allow inlining always_inline functions into no_sanitize_address
268 functions. */
269 if (!sanitize_flags_p (SANITIZE_ADDRESS, caller)
270 && lookup_attribute ("always_inline", DECL_ATTRIBUTES (callee)))
271 return true;
273 return ((sanitize_flags_p (SANITIZE_ADDRESS, caller)
274 == sanitize_flags_p (SANITIZE_ADDRESS, callee))
275 && (sanitize_flags_p (SANITIZE_POINTER_COMPARE, caller)
276 == sanitize_flags_p (SANITIZE_POINTER_COMPARE, callee))
277 && (sanitize_flags_p (SANITIZE_POINTER_SUBTRACT, caller)
278 == sanitize_flags_p (SANITIZE_POINTER_SUBTRACT, callee)));
281 /* Used for flags where it is safe to inline when caller's value is
282 grater than callee's. */
283 #define check_maybe_up(flag) \
284 (opts_for_fn (caller->decl)->x_##flag \
285 != opts_for_fn (callee->decl)->x_##flag \
286 && (!always_inline \
287 || opts_for_fn (caller->decl)->x_##flag \
288 < opts_for_fn (callee->decl)->x_##flag))
289 /* Used for flags where it is safe to inline when caller's value is
290 smaller than callee's. */
291 #define check_maybe_down(flag) \
292 (opts_for_fn (caller->decl)->x_##flag \
293 != opts_for_fn (callee->decl)->x_##flag \
294 && (!always_inline \
295 || opts_for_fn (caller->decl)->x_##flag \
296 > opts_for_fn (callee->decl)->x_##flag))
297 /* Used for flags where exact match is needed for correctness. */
298 #define check_match(flag) \
299 (opts_for_fn (caller->decl)->x_##flag \
300 != opts_for_fn (callee->decl)->x_##flag)
302 /* Decide if we can inline the edge and possibly update
303 inline_failed reason.
304 We check whether inlining is possible at all and whether
305 caller growth limits allow doing so.
307 if REPORT is true, output reason to the dump file. */
309 static bool
310 can_inline_edge_p (struct cgraph_edge *e, bool report,
311 bool early = false)
313 gcc_checking_assert (e->inline_failed);
315 if (cgraph_inline_failed_type (e->inline_failed) == CIF_FINAL_ERROR)
317 if (report)
318 report_inline_failed_reason (e);
319 return false;
322 bool inlinable = true;
323 enum availability avail;
324 cgraph_node *caller = e->caller->global.inlined_to
325 ? e->caller->global.inlined_to : e->caller;
326 cgraph_node *callee = e->callee->ultimate_alias_target (&avail, caller);
328 if (!callee->definition)
330 e->inline_failed = CIF_BODY_NOT_AVAILABLE;
331 inlinable = false;
333 if (!early && (!opt_for_fn (callee->decl, optimize)
334 || !opt_for_fn (caller->decl, optimize)))
336 e->inline_failed = CIF_FUNCTION_NOT_OPTIMIZED;
337 inlinable = false;
339 else if (callee->calls_comdat_local)
341 e->inline_failed = CIF_USES_COMDAT_LOCAL;
342 inlinable = false;
344 else if (avail <= AVAIL_INTERPOSABLE)
346 e->inline_failed = CIF_OVERWRITABLE;
347 inlinable = false;
349 /* All edges with call_stmt_cannot_inline_p should have inline_failed
350 initialized to one of FINAL_ERROR reasons. */
351 else if (e->call_stmt_cannot_inline_p)
352 gcc_unreachable ();
353 /* Don't inline if the functions have different EH personalities. */
354 else if (DECL_FUNCTION_PERSONALITY (caller->decl)
355 && DECL_FUNCTION_PERSONALITY (callee->decl)
356 && (DECL_FUNCTION_PERSONALITY (caller->decl)
357 != DECL_FUNCTION_PERSONALITY (callee->decl)))
359 e->inline_failed = CIF_EH_PERSONALITY;
360 inlinable = false;
362 /* TM pure functions should not be inlined into non-TM_pure
363 functions. */
364 else if (is_tm_pure (callee->decl) && !is_tm_pure (caller->decl))
366 e->inline_failed = CIF_UNSPECIFIED;
367 inlinable = false;
369 /* Check compatibility of target optimization options. */
370 else if (!targetm.target_option.can_inline_p (caller->decl,
371 callee->decl))
373 e->inline_failed = CIF_TARGET_OPTION_MISMATCH;
374 inlinable = false;
376 else if (ipa_fn_summaries->get (callee) == NULL
377 || !ipa_fn_summaries->get (callee)->inlinable)
379 e->inline_failed = CIF_FUNCTION_NOT_INLINABLE;
380 inlinable = false;
382 /* Don't inline a function with mismatched sanitization attributes. */
383 else if (!sanitize_attrs_match_for_inline_p (caller->decl, callee->decl))
385 e->inline_failed = CIF_ATTRIBUTE_MISMATCH;
386 inlinable = false;
388 else if (callee->externally_visible
389 && flag_live_patching == LIVE_PATCHING_INLINE_ONLY_STATIC)
391 e->inline_failed = CIF_EXTERN_LIVE_ONLY_STATIC;
392 inlinable = false;
394 if (!inlinable && report)
395 report_inline_failed_reason (e);
396 return inlinable;
399 /* Decide if we can inline the edge and possibly update
400 inline_failed reason.
401 We check whether inlining is possible at all and whether
402 caller growth limits allow doing so.
404 if REPORT is true, output reason to the dump file.
406 if DISREGARD_LIMITS is true, ignore size limits. */
408 static bool
409 can_inline_edge_by_limits_p (struct cgraph_edge *e, bool report,
410 bool disregard_limits = false, bool early = false)
412 gcc_checking_assert (e->inline_failed);
414 if (cgraph_inline_failed_type (e->inline_failed) == CIF_FINAL_ERROR)
416 if (report)
417 report_inline_failed_reason (e);
418 return false;
421 bool inlinable = true;
422 enum availability avail;
423 cgraph_node *caller = e->caller->global.inlined_to
424 ? e->caller->global.inlined_to : e->caller;
425 cgraph_node *callee = e->callee->ultimate_alias_target (&avail, caller);
426 tree caller_tree = DECL_FUNCTION_SPECIFIC_OPTIMIZATION (caller->decl);
427 tree callee_tree
428 = callee ? DECL_FUNCTION_SPECIFIC_OPTIMIZATION (callee->decl) : NULL;
429 /* Check if caller growth allows the inlining. */
430 if (!DECL_DISREGARD_INLINE_LIMITS (callee->decl)
431 && !disregard_limits
432 && !lookup_attribute ("flatten",
433 DECL_ATTRIBUTES (caller->decl))
434 && !caller_growth_limits (e))
435 inlinable = false;
436 /* Don't inline a function with a higher optimization level than the
437 caller. FIXME: this is really just tip of iceberg of handling
438 optimization attribute. */
439 else if (caller_tree != callee_tree)
441 bool always_inline =
442 (DECL_DISREGARD_INLINE_LIMITS (callee->decl)
443 && lookup_attribute ("always_inline",
444 DECL_ATTRIBUTES (callee->decl)));
445 ipa_fn_summary *caller_info = ipa_fn_summaries->get (caller);
446 ipa_fn_summary *callee_info = ipa_fn_summaries->get (callee);
448 /* Until GCC 4.9 we did not check the semantics-altering flags
449 below and inlined across optimization boundaries.
450 Enabling checks below breaks several packages by refusing
451 to inline library always_inline functions. See PR65873.
452 Disable the check for early inlining for now until better solution
453 is found. */
454 if (always_inline && early)
456 /* There are some options that change IL semantics which means
457 we cannot inline in these cases for correctness reason.
458 Not even for always_inline declared functions. */
459 else if (check_match (flag_wrapv)
460 || check_match (flag_trapv)
461 || check_match (flag_pcc_struct_return)
462 /* When caller or callee does FP math, be sure FP codegen flags
463 compatible. */
464 || ((caller_info->fp_expressions && callee_info->fp_expressions)
465 && (check_maybe_up (flag_rounding_math)
466 || check_maybe_up (flag_trapping_math)
467 || check_maybe_down (flag_unsafe_math_optimizations)
468 || check_maybe_down (flag_finite_math_only)
469 || check_maybe_up (flag_signaling_nans)
470 || check_maybe_down (flag_cx_limited_range)
471 || check_maybe_up (flag_signed_zeros)
472 || check_maybe_down (flag_associative_math)
473 || check_maybe_down (flag_reciprocal_math)
474 || check_maybe_down (flag_fp_int_builtin_inexact)
475 /* Strictly speaking only when the callee contains function
476 calls that may end up setting errno. */
477 || check_maybe_up (flag_errno_math)))
478 /* We do not want to make code compiled with exceptions to be
479 brought into a non-EH function unless we know that the callee
480 does not throw.
481 This is tracked by DECL_FUNCTION_PERSONALITY. */
482 || (check_maybe_up (flag_non_call_exceptions)
483 && DECL_FUNCTION_PERSONALITY (callee->decl))
484 || (check_maybe_up (flag_exceptions)
485 && DECL_FUNCTION_PERSONALITY (callee->decl))
486 /* When devirtualization is diabled for callee, it is not safe
487 to inline it as we possibly mangled the type info.
488 Allow early inlining of always inlines. */
489 || (!early && check_maybe_down (flag_devirtualize)))
491 e->inline_failed = CIF_OPTIMIZATION_MISMATCH;
492 inlinable = false;
494 /* gcc.dg/pr43564.c. Apply user-forced inline even at -O0. */
495 else if (always_inline)
497 /* When user added an attribute to the callee honor it. */
498 else if (lookup_attribute ("optimize", DECL_ATTRIBUTES (callee->decl))
499 && opts_for_fn (caller->decl) != opts_for_fn (callee->decl))
501 e->inline_failed = CIF_OPTIMIZATION_MISMATCH;
502 inlinable = false;
504 /* If explicit optimize attribute are not used, the mismatch is caused
505 by different command line options used to build different units.
506 Do not care about COMDAT functions - those are intended to be
507 optimized with the optimization flags of module they are used in.
508 Also do not care about mixing up size/speed optimization when
509 DECL_DISREGARD_INLINE_LIMITS is set. */
510 else if ((callee->merged_comdat
511 && !lookup_attribute ("optimize",
512 DECL_ATTRIBUTES (caller->decl)))
513 || DECL_DISREGARD_INLINE_LIMITS (callee->decl))
515 /* If mismatch is caused by merging two LTO units with different
516 optimizationflags we want to be bit nicer. However never inline
517 if one of functions is not optimized at all. */
518 else if (!opt_for_fn (callee->decl, optimize)
519 || !opt_for_fn (caller->decl, optimize))
521 e->inline_failed = CIF_OPTIMIZATION_MISMATCH;
522 inlinable = false;
524 /* If callee is optimized for size and caller is not, allow inlining if
525 code shrinks or we are in MAX_INLINE_INSNS_SINGLE limit and callee
526 is inline (and thus likely an unified comdat). This will allow caller
527 to run faster. */
528 else if (opt_for_fn (callee->decl, optimize_size)
529 > opt_for_fn (caller->decl, optimize_size))
531 int growth = estimate_edge_growth (e);
532 if (growth > PARAM_VALUE (PARAM_MAX_INLINE_INSNS_SIZE)
533 && (!DECL_DECLARED_INLINE_P (callee->decl)
534 && growth >= MAX (MAX_INLINE_INSNS_SINGLE,
535 MAX_INLINE_INSNS_AUTO)))
537 e->inline_failed = CIF_OPTIMIZATION_MISMATCH;
538 inlinable = false;
541 /* If callee is more aggressively optimized for performance than caller,
542 we generally want to inline only cheap (runtime wise) functions. */
543 else if (opt_for_fn (callee->decl, optimize_size)
544 < opt_for_fn (caller->decl, optimize_size)
545 || (opt_for_fn (callee->decl, optimize)
546 > opt_for_fn (caller->decl, optimize)))
548 if (estimate_edge_time (e)
549 >= 20 + ipa_call_summaries->get (e)->call_stmt_time)
551 e->inline_failed = CIF_OPTIMIZATION_MISMATCH;
552 inlinable = false;
558 if (!inlinable && report)
559 report_inline_failed_reason (e);
560 return inlinable;
564 /* Return true if the edge E is inlinable during early inlining. */
566 static bool
567 can_early_inline_edge_p (struct cgraph_edge *e)
569 struct cgraph_node *callee = e->callee->ultimate_alias_target ();
570 /* Early inliner might get called at WPA stage when IPA pass adds new
571 function. In this case we cannot really do any of early inlining
572 because function bodies are missing. */
573 if (cgraph_inline_failed_type (e->inline_failed) == CIF_FINAL_ERROR)
574 return false;
575 if (!gimple_has_body_p (callee->decl))
577 e->inline_failed = CIF_BODY_NOT_AVAILABLE;
578 return false;
580 /* In early inliner some of callees may not be in SSA form yet
581 (i.e. the callgraph is cyclic and we did not process
582 the callee by early inliner, yet). We don't have CIF code for this
583 case; later we will re-do the decision in the real inliner. */
584 if (!gimple_in_ssa_p (DECL_STRUCT_FUNCTION (e->caller->decl))
585 || !gimple_in_ssa_p (DECL_STRUCT_FUNCTION (callee->decl)))
587 if (dump_enabled_p ())
588 dump_printf_loc (MSG_MISSED_OPTIMIZATION, e->call_stmt,
589 " edge not inlinable: not in SSA form\n");
590 return false;
592 if (!can_inline_edge_p (e, true, true)
593 || !can_inline_edge_by_limits_p (e, true, false, true))
594 return false;
595 return true;
599 /* Return number of calls in N. Ignore cheap builtins. */
601 static int
602 num_calls (struct cgraph_node *n)
604 struct cgraph_edge *e;
605 int num = 0;
607 for (e = n->callees; e; e = e->next_callee)
608 if (!is_inexpensive_builtin (e->callee->decl))
609 num++;
610 return num;
614 /* Return true if we are interested in inlining small function. */
616 static bool
617 want_early_inline_function_p (struct cgraph_edge *e)
619 bool want_inline = true;
620 struct cgraph_node *callee = e->callee->ultimate_alias_target ();
622 if (DECL_DISREGARD_INLINE_LIMITS (callee->decl))
624 /* For AutoFDO, we need to make sure that before profile summary, all
625 hot paths' IR look exactly the same as profiled binary. As a result,
626 in einliner, we will disregard size limit and inline those callsites
627 that are:
628 * inlined in the profiled binary, and
629 * the cloned callee has enough samples to be considered "hot". */
630 else if (flag_auto_profile && afdo_callsite_hot_enough_for_early_inline (e))
632 else if (!DECL_DECLARED_INLINE_P (callee->decl)
633 && !opt_for_fn (e->caller->decl, flag_inline_small_functions))
635 e->inline_failed = CIF_FUNCTION_NOT_INLINE_CANDIDATE;
636 report_inline_failed_reason (e);
637 want_inline = false;
639 else
641 int growth = estimate_edge_growth (e);
642 int n;
644 if (growth <= PARAM_VALUE (PARAM_MAX_INLINE_INSNS_SIZE))
646 else if (!e->maybe_hot_p ())
648 if (dump_enabled_p ())
649 dump_printf_loc (MSG_MISSED_OPTIMIZATION, e->call_stmt,
650 " will not early inline: %C->%C, "
651 "call is cold and code would grow by %i\n",
652 e->caller, callee,
653 growth);
654 want_inline = false;
656 else if (growth > PARAM_VALUE (PARAM_EARLY_INLINING_INSNS))
658 if (dump_enabled_p ())
659 dump_printf_loc (MSG_MISSED_OPTIMIZATION, e->call_stmt,
660 " will not early inline: %C->%C, "
661 "growth %i exceeds --param early-inlining-insns\n",
662 e->caller, callee,
663 growth);
664 want_inline = false;
666 else if ((n = num_calls (callee)) != 0
667 && growth * (n + 1) > PARAM_VALUE (PARAM_EARLY_INLINING_INSNS))
669 if (dump_enabled_p ())
670 dump_printf_loc (MSG_MISSED_OPTIMIZATION, e->call_stmt,
671 " will not early inline: %C->%C, "
672 "growth %i exceeds --param early-inlining-insns "
673 "divided by number of calls\n",
674 e->caller, callee,
675 growth);
676 want_inline = false;
679 return want_inline;
682 /* Compute time of the edge->caller + edge->callee execution when inlining
683 does not happen. */
685 inline sreal
686 compute_uninlined_call_time (struct cgraph_edge *edge,
687 sreal uninlined_call_time)
689 cgraph_node *caller = (edge->caller->global.inlined_to
690 ? edge->caller->global.inlined_to
691 : edge->caller);
693 sreal freq = edge->sreal_frequency ();
694 if (freq > 0)
695 uninlined_call_time *= freq;
696 else
697 uninlined_call_time = uninlined_call_time >> 11;
699 sreal caller_time = ipa_fn_summaries->get (caller)->time;
700 return uninlined_call_time + caller_time;
703 /* Same as compute_uinlined_call_time but compute time when inlining
704 does happen. */
706 inline sreal
707 compute_inlined_call_time (struct cgraph_edge *edge,
708 sreal time)
710 cgraph_node *caller = (edge->caller->global.inlined_to
711 ? edge->caller->global.inlined_to
712 : edge->caller);
713 sreal caller_time = ipa_fn_summaries->get (caller)->time;
715 sreal freq = edge->sreal_frequency ();
716 if (freq > 0)
717 time *= freq;
718 else
719 time = time >> 11;
721 /* This calculation should match one in ipa-inline-analysis.c
722 (estimate_edge_size_and_time). */
723 time -= (sreal)ipa_call_summaries->get (edge)->call_stmt_time * freq;
724 time += caller_time;
725 if (time <= 0)
726 time = ((sreal) 1) >> 8;
727 gcc_checking_assert (time >= 0);
728 return time;
731 /* Return true if the speedup for inlining E is bigger than
732 PARAM_MAX_INLINE_MIN_SPEEDUP. */
734 static bool
735 big_speedup_p (struct cgraph_edge *e)
737 sreal unspec_time;
738 sreal spec_time = estimate_edge_time (e, &unspec_time);
739 sreal time = compute_uninlined_call_time (e, unspec_time);
740 sreal inlined_time = compute_inlined_call_time (e, spec_time);
742 if ((time - inlined_time) * 100
743 > (sreal) (time * PARAM_VALUE (PARAM_INLINE_MIN_SPEEDUP)))
744 return true;
745 return false;
748 /* Return true if we are interested in inlining small function.
749 When REPORT is true, report reason to dump file. */
751 static bool
752 want_inline_small_function_p (struct cgraph_edge *e, bool report)
754 bool want_inline = true;
755 struct cgraph_node *callee = e->callee->ultimate_alias_target ();
757 /* Allow this function to be called before can_inline_edge_p,
758 since it's usually cheaper. */
759 if (cgraph_inline_failed_type (e->inline_failed) == CIF_FINAL_ERROR)
760 want_inline = false;
761 else if (DECL_DISREGARD_INLINE_LIMITS (callee->decl))
763 else if (!DECL_DECLARED_INLINE_P (callee->decl)
764 && !opt_for_fn (e->caller->decl, flag_inline_small_functions))
766 e->inline_failed = CIF_FUNCTION_NOT_INLINE_CANDIDATE;
767 want_inline = false;
769 /* Do fast and conservative check if the function can be good
770 inline candidate. At the moment we allow inline hints to
771 promote non-inline functions to inline and we increase
772 MAX_INLINE_INSNS_SINGLE 16-fold for inline functions. */
773 else if ((!DECL_DECLARED_INLINE_P (callee->decl)
774 && (!e->count.ipa ().initialized_p () || !e->maybe_hot_p ()))
775 && ipa_fn_summaries->get (callee)->min_size
776 - ipa_call_summaries->get (e)->call_stmt_size
777 > MAX (MAX_INLINE_INSNS_SINGLE, MAX_INLINE_INSNS_AUTO))
779 e->inline_failed = CIF_MAX_INLINE_INSNS_AUTO_LIMIT;
780 want_inline = false;
782 else if ((DECL_DECLARED_INLINE_P (callee->decl)
783 || e->count.ipa ().nonzero_p ())
784 && ipa_fn_summaries->get (callee)->min_size
785 - ipa_call_summaries->get (e)->call_stmt_size
786 > 16 * MAX_INLINE_INSNS_SINGLE)
788 e->inline_failed = (DECL_DECLARED_INLINE_P (callee->decl)
789 ? CIF_MAX_INLINE_INSNS_SINGLE_LIMIT
790 : CIF_MAX_INLINE_INSNS_AUTO_LIMIT);
791 want_inline = false;
793 else
795 int growth = estimate_edge_growth (e);
796 ipa_hints hints = estimate_edge_hints (e);
797 int big_speedup = -1; /* compute this lazily */
799 if (growth <= PARAM_VALUE (PARAM_MAX_INLINE_INSNS_SIZE))
801 /* Apply MAX_INLINE_INSNS_SINGLE limit. Do not do so when
802 hints suggests that inlining given function is very profitable. */
803 else if (DECL_DECLARED_INLINE_P (callee->decl)
804 && growth >= MAX_INLINE_INSNS_SINGLE
805 && (growth >= MAX_INLINE_INSNS_SINGLE * 16
806 || (!(hints & (INLINE_HINT_indirect_call
807 | INLINE_HINT_known_hot
808 | INLINE_HINT_loop_iterations
809 | INLINE_HINT_array_index
810 | INLINE_HINT_loop_stride))
811 && !(big_speedup = big_speedup_p (e)))))
813 e->inline_failed = CIF_MAX_INLINE_INSNS_SINGLE_LIMIT;
814 want_inline = false;
816 else if (!DECL_DECLARED_INLINE_P (callee->decl)
817 && !opt_for_fn (e->caller->decl, flag_inline_functions)
818 && growth >= PARAM_VALUE (PARAM_MAX_INLINE_INSNS_SMALL))
820 /* growth_likely_positive is expensive, always test it last. */
821 if (growth >= MAX_INLINE_INSNS_SINGLE
822 || growth_likely_positive (callee, growth))
824 e->inline_failed = CIF_NOT_DECLARED_INLINED;
825 want_inline = false;
828 /* Apply MAX_INLINE_INSNS_AUTO limit for functions not declared inline
829 Upgrade it to MAX_INLINE_INSNS_SINGLE when hints suggests that
830 inlining given function is very profitable. */
831 else if (!DECL_DECLARED_INLINE_P (callee->decl)
832 && !(hints & INLINE_HINT_known_hot)
833 && growth >= ((hints & (INLINE_HINT_indirect_call
834 | INLINE_HINT_loop_iterations
835 | INLINE_HINT_array_index
836 | INLINE_HINT_loop_stride))
837 ? MAX (MAX_INLINE_INSNS_AUTO,
838 MAX_INLINE_INSNS_SINGLE)
839 : MAX_INLINE_INSNS_AUTO)
840 && !(big_speedup == -1 ? big_speedup_p (e) : big_speedup))
842 /* growth_likely_positive is expensive, always test it last. */
843 if (growth >= MAX_INLINE_INSNS_SINGLE
844 || growth_likely_positive (callee, growth))
846 e->inline_failed = CIF_MAX_INLINE_INSNS_AUTO_LIMIT;
847 want_inline = false;
850 /* If call is cold, do not inline when function body would grow. */
851 else if (!e->maybe_hot_p ()
852 && (growth >= MAX_INLINE_INSNS_SINGLE
853 || growth_likely_positive (callee, growth)))
855 e->inline_failed = CIF_UNLIKELY_CALL;
856 want_inline = false;
859 if (!want_inline && report)
860 report_inline_failed_reason (e);
861 return want_inline;
864 /* EDGE is self recursive edge.
865 We hand two cases - when function A is inlining into itself
866 or when function A is being inlined into another inliner copy of function
867 A within function B.
869 In first case OUTER_NODE points to the toplevel copy of A, while
870 in the second case OUTER_NODE points to the outermost copy of A in B.
872 In both cases we want to be extra selective since
873 inlining the call will just introduce new recursive calls to appear. */
875 static bool
876 want_inline_self_recursive_call_p (struct cgraph_edge *edge,
877 struct cgraph_node *outer_node,
878 bool peeling,
879 int depth)
881 char const *reason = NULL;
882 bool want_inline = true;
883 sreal caller_freq = 1;
884 int max_depth = PARAM_VALUE (PARAM_MAX_INLINE_RECURSIVE_DEPTH_AUTO);
886 if (DECL_DECLARED_INLINE_P (edge->caller->decl))
887 max_depth = PARAM_VALUE (PARAM_MAX_INLINE_RECURSIVE_DEPTH);
889 if (!edge->maybe_hot_p ())
891 reason = "recursive call is cold";
892 want_inline = false;
894 else if (depth > max_depth)
896 reason = "--param max-inline-recursive-depth exceeded.";
897 want_inline = false;
899 else if (outer_node->global.inlined_to
900 && (caller_freq = outer_node->callers->sreal_frequency ()) == 0)
902 reason = "caller frequency is 0";
903 want_inline = false;
906 if (!want_inline)
908 /* Inlining of self recursive function into copy of itself within other
909 function is transformation similar to loop peeling.
911 Peeling is profitable if we can inline enough copies to make probability
912 of actual call to the self recursive function very small. Be sure that
913 the probability of recursion is small.
915 We ensure that the frequency of recursing is at most 1 - (1/max_depth).
916 This way the expected number of recursion is at most max_depth. */
917 else if (peeling)
919 sreal max_prob = (sreal)1 - ((sreal)1 / (sreal)max_depth);
920 int i;
921 for (i = 1; i < depth; i++)
922 max_prob = max_prob * max_prob;
923 if (edge->sreal_frequency () >= max_prob * caller_freq)
925 reason = "frequency of recursive call is too large";
926 want_inline = false;
929 /* Recursive inlining, i.e. equivalent of unrolling, is profitable if
930 recursion depth is large. We reduce function call overhead and increase
931 chances that things fit in hardware return predictor.
933 Recursive inlining might however increase cost of stack frame setup
934 actually slowing down functions whose recursion tree is wide rather than
935 deep.
937 Deciding reliably on when to do recursive inlining without profile feedback
938 is tricky. For now we disable recursive inlining when probability of self
939 recursion is low.
941 Recursive inlining of self recursive call within loop also results in
942 large loop depths that generally optimize badly. We may want to throttle
943 down inlining in those cases. In particular this seems to happen in one
944 of libstdc++ rb tree methods. */
945 else
947 if (edge->sreal_frequency () * 100
948 <= caller_freq
949 * PARAM_VALUE (PARAM_MIN_INLINE_RECURSIVE_PROBABILITY))
951 reason = "frequency of recursive call is too small";
952 want_inline = false;
955 if (!want_inline && dump_enabled_p ())
956 dump_printf_loc (MSG_MISSED_OPTIMIZATION, edge->call_stmt,
957 " not inlining recursively: %s\n", reason);
958 return want_inline;
961 /* Return true when NODE has uninlinable caller;
962 set HAS_HOT_CALL if it has hot call.
963 Worker for cgraph_for_node_and_aliases. */
965 static bool
966 check_callers (struct cgraph_node *node, void *has_hot_call)
968 struct cgraph_edge *e;
969 for (e = node->callers; e; e = e->next_caller)
971 if (!opt_for_fn (e->caller->decl, flag_inline_functions_called_once)
972 || !opt_for_fn (e->caller->decl, optimize))
973 return true;
974 if (!can_inline_edge_p (e, true))
975 return true;
976 if (e->recursive_p ())
977 return true;
978 if (!can_inline_edge_by_limits_p (e, true))
979 return true;
980 if (!(*(bool *)has_hot_call) && e->maybe_hot_p ())
981 *(bool *)has_hot_call = true;
983 return false;
986 /* If NODE has a caller, return true. */
988 static bool
989 has_caller_p (struct cgraph_node *node, void *data ATTRIBUTE_UNUSED)
991 if (node->callers)
992 return true;
993 return false;
996 /* Decide if inlining NODE would reduce unit size by eliminating
997 the offline copy of function.
998 When COLD is true the cold calls are considered, too. */
1000 static bool
1001 want_inline_function_to_all_callers_p (struct cgraph_node *node, bool cold)
1003 bool has_hot_call = false;
1005 /* Aliases gets inlined along with the function they alias. */
1006 if (node->alias)
1007 return false;
1008 /* Already inlined? */
1009 if (node->global.inlined_to)
1010 return false;
1011 /* Does it have callers? */
1012 if (!node->call_for_symbol_and_aliases (has_caller_p, NULL, true))
1013 return false;
1014 /* Inlining into all callers would increase size? */
1015 if (estimate_growth (node) > 0)
1016 return false;
1017 /* All inlines must be possible. */
1018 if (node->call_for_symbol_and_aliases (check_callers, &has_hot_call,
1019 true))
1020 return false;
1021 if (!cold && !has_hot_call)
1022 return false;
1023 return true;
1026 /* A cost model driving the inlining heuristics in a way so the edges with
1027 smallest badness are inlined first. After each inlining is performed
1028 the costs of all caller edges of nodes affected are recomputed so the
1029 metrics may accurately depend on values such as number of inlinable callers
1030 of the function or function body size. */
1032 static sreal
1033 edge_badness (struct cgraph_edge *edge, bool dump)
1035 sreal badness;
1036 int growth;
1037 sreal edge_time, unspec_edge_time;
1038 struct cgraph_node *callee = edge->callee->ultimate_alias_target ();
1039 struct ipa_fn_summary *callee_info = ipa_fn_summaries->get (callee);
1040 ipa_hints hints;
1041 cgraph_node *caller = (edge->caller->global.inlined_to
1042 ? edge->caller->global.inlined_to
1043 : edge->caller);
1045 growth = estimate_edge_growth (edge);
1046 edge_time = estimate_edge_time (edge, &unspec_edge_time);
1047 hints = estimate_edge_hints (edge);
1048 gcc_checking_assert (edge_time >= 0);
1049 /* Check that inlined time is better, but tolerate some roundoff issues.
1050 FIXME: When callee profile drops to 0 we account calls more. This
1051 should be fixed by never doing that. */
1052 gcc_checking_assert ((edge_time * 100
1053 - callee_info->time * 101).to_int () <= 0
1054 || callee->count.ipa ().initialized_p ());
1055 gcc_checking_assert (growth <= callee_info->size);
1057 if (dump)
1059 fprintf (dump_file, " Badness calculation for %s -> %s\n",
1060 edge->caller->dump_name (),
1061 edge->callee->dump_name ());
1062 fprintf (dump_file, " size growth %i, time %f unspec %f ",
1063 growth,
1064 edge_time.to_double (),
1065 unspec_edge_time.to_double ());
1066 ipa_dump_hints (dump_file, hints);
1067 if (big_speedup_p (edge))
1068 fprintf (dump_file, " big_speedup");
1069 fprintf (dump_file, "\n");
1072 /* Always prefer inlining saving code size. */
1073 if (growth <= 0)
1075 badness = (sreal) (-SREAL_MIN_SIG + growth) << (SREAL_MAX_EXP / 256);
1076 if (dump)
1077 fprintf (dump_file, " %f: Growth %d <= 0\n", badness.to_double (),
1078 growth);
1080 /* Inlining into EXTERNAL functions is not going to change anything unless
1081 they are themselves inlined. */
1082 else if (DECL_EXTERNAL (caller->decl))
1084 if (dump)
1085 fprintf (dump_file, " max: function is external\n");
1086 return sreal::max ();
1088 /* When profile is available. Compute badness as:
1090 time_saved * caller_count
1091 goodness = -------------------------------------------------
1092 growth_of_caller * overall_growth * combined_size
1094 badness = - goodness
1096 Again use negative value to make calls with profile appear hotter
1097 then calls without.
1099 else if (opt_for_fn (caller->decl, flag_guess_branch_prob)
1100 || caller->count.ipa ().nonzero_p ())
1102 sreal numerator, denominator;
1103 int overall_growth;
1104 sreal inlined_time = compute_inlined_call_time (edge, edge_time);
1106 numerator = (compute_uninlined_call_time (edge, unspec_edge_time)
1107 - inlined_time);
1108 if (numerator <= 0)
1109 numerator = ((sreal) 1 >> 8);
1110 if (caller->count.ipa ().nonzero_p ())
1111 numerator *= caller->count.ipa ().to_gcov_type ();
1112 else if (caller->count.ipa ().initialized_p ())
1113 numerator = numerator >> 11;
1114 denominator = growth;
1116 overall_growth = callee_info->growth;
1118 /* Look for inliner wrappers of the form:
1120 inline_caller ()
1122 do_fast_job...
1123 if (need_more_work)
1124 noninline_callee ();
1126 Withhout panilizing this case, we usually inline noninline_callee
1127 into the inline_caller because overall_growth is small preventing
1128 further inlining of inline_caller.
1130 Penalize only callgraph edges to functions with small overall
1131 growth ...
1133 if (growth > overall_growth
1134 /* ... and having only one caller which is not inlined ... */
1135 && callee_info->single_caller
1136 && !edge->caller->global.inlined_to
1137 /* ... and edges executed only conditionally ... */
1138 && edge->sreal_frequency () < 1
1139 /* ... consider case where callee is not inline but caller is ... */
1140 && ((!DECL_DECLARED_INLINE_P (edge->callee->decl)
1141 && DECL_DECLARED_INLINE_P (caller->decl))
1142 /* ... or when early optimizers decided to split and edge
1143 frequency still indicates splitting is a win ... */
1144 || (callee->split_part && !caller->split_part
1145 && edge->sreal_frequency () * 100
1146 < PARAM_VALUE
1147 (PARAM_PARTIAL_INLINING_ENTRY_PROBABILITY)
1148 /* ... and do not overwrite user specified hints. */
1149 && (!DECL_DECLARED_INLINE_P (edge->callee->decl)
1150 || DECL_DECLARED_INLINE_P (caller->decl)))))
1152 ipa_fn_summary *caller_info = ipa_fn_summaries->get (caller);
1153 int caller_growth = caller_info->growth;
1155 /* Only apply the penalty when caller looks like inline candidate,
1156 and it is not called once and. */
1157 if (!caller_info->single_caller && overall_growth < caller_growth
1158 && caller_info->inlinable
1159 && caller_info->size
1160 < (DECL_DECLARED_INLINE_P (caller->decl)
1161 ? MAX_INLINE_INSNS_SINGLE : MAX_INLINE_INSNS_AUTO))
1163 if (dump)
1164 fprintf (dump_file,
1165 " Wrapper penalty. Increasing growth %i to %i\n",
1166 overall_growth, caller_growth);
1167 overall_growth = caller_growth;
1170 if (overall_growth > 0)
1172 /* Strongly preffer functions with few callers that can be inlined
1173 fully. The square root here leads to smaller binaries at average.
1174 Watch however for extreme cases and return to linear function
1175 when growth is large. */
1176 if (overall_growth < 256)
1177 overall_growth *= overall_growth;
1178 else
1179 overall_growth += 256 * 256 - 256;
1180 denominator *= overall_growth;
1182 denominator *= ipa_fn_summaries->get (caller)->self_size + growth;
1184 badness = - numerator / denominator;
1186 if (dump)
1188 fprintf (dump_file,
1189 " %f: guessed profile. frequency %f, count %" PRId64
1190 " caller count %" PRId64
1191 " time w/o inlining %f, time with inlining %f"
1192 " overall growth %i (current) %i (original)"
1193 " %i (compensated)\n",
1194 badness.to_double (),
1195 edge->sreal_frequency ().to_double (),
1196 edge->count.ipa ().initialized_p () ? edge->count.ipa ().to_gcov_type () : -1,
1197 caller->count.ipa ().initialized_p () ? caller->count.ipa ().to_gcov_type () : -1,
1198 compute_uninlined_call_time (edge,
1199 unspec_edge_time).to_double (),
1200 inlined_time.to_double (),
1201 estimate_growth (callee),
1202 callee_info->growth, overall_growth);
1205 /* When function local profile is not available or it does not give
1206 useful information (ie frequency is zero), base the cost on
1207 loop nest and overall size growth, so we optimize for overall number
1208 of functions fully inlined in program. */
1209 else
1211 int nest = MIN (ipa_call_summaries->get (edge)->loop_depth, 8);
1212 badness = growth;
1214 /* Decrease badness if call is nested. */
1215 if (badness > 0)
1216 badness = badness >> nest;
1217 else
1218 badness = badness << nest;
1219 if (dump)
1220 fprintf (dump_file, " %f: no profile. nest %i\n",
1221 badness.to_double (), nest);
1223 gcc_checking_assert (badness != 0);
1225 if (edge->recursive_p ())
1226 badness = badness.shift (badness > 0 ? 4 : -4);
1227 if ((hints & (INLINE_HINT_indirect_call
1228 | INLINE_HINT_loop_iterations
1229 | INLINE_HINT_array_index
1230 | INLINE_HINT_loop_stride))
1231 || callee_info->growth <= 0)
1232 badness = badness.shift (badness > 0 ? -2 : 2);
1233 if (hints & (INLINE_HINT_same_scc))
1234 badness = badness.shift (badness > 0 ? 3 : -3);
1235 else if (hints & (INLINE_HINT_in_scc))
1236 badness = badness.shift (badness > 0 ? 2 : -2);
1237 else if (hints & (INLINE_HINT_cross_module))
1238 badness = badness.shift (badness > 0 ? 1 : -1);
1239 if (DECL_DISREGARD_INLINE_LIMITS (callee->decl))
1240 badness = badness.shift (badness > 0 ? -4 : 4);
1241 else if ((hints & INLINE_HINT_declared_inline))
1242 badness = badness.shift (badness > 0 ? -3 : 3);
1243 if (dump)
1244 fprintf (dump_file, " Adjusted by hints %f\n", badness.to_double ());
1245 return badness;
1248 /* Recompute badness of EDGE and update its key in HEAP if needed. */
1249 static inline void
1250 update_edge_key (edge_heap_t *heap, struct cgraph_edge *edge)
1252 sreal badness = edge_badness (edge, false);
1253 if (edge->aux)
1255 edge_heap_node_t *n = (edge_heap_node_t *) edge->aux;
1256 gcc_checking_assert (n->get_data () == edge);
1258 /* fibonacci_heap::replace_key does busy updating of the
1259 heap that is unnecesarily expensive.
1260 We do lazy increases: after extracting minimum if the key
1261 turns out to be out of date, it is re-inserted into heap
1262 with correct value. */
1263 if (badness < n->get_key ())
1265 if (dump_file && (dump_flags & TDF_DETAILS))
1267 fprintf (dump_file,
1268 " decreasing badness %s -> %s, %f to %f\n",
1269 edge->caller->dump_name (),
1270 edge->callee->dump_name (),
1271 n->get_key ().to_double (),
1272 badness.to_double ());
1274 heap->decrease_key (n, badness);
1277 else
1279 if (dump_file && (dump_flags & TDF_DETAILS))
1281 fprintf (dump_file,
1282 " enqueuing call %s -> %s, badness %f\n",
1283 edge->caller->dump_name (),
1284 edge->callee->dump_name (),
1285 badness.to_double ());
1287 edge->aux = heap->insert (badness, edge);
1292 /* NODE was inlined.
1293 All caller edges needs to be resetted because
1294 size estimates change. Similarly callees needs reset
1295 because better context may be known. */
1297 static void
1298 reset_edge_caches (struct cgraph_node *node)
1300 struct cgraph_edge *edge;
1301 struct cgraph_edge *e = node->callees;
1302 struct cgraph_node *where = node;
1303 struct ipa_ref *ref;
1305 if (where->global.inlined_to)
1306 where = where->global.inlined_to;
1308 if (edge_growth_cache != NULL)
1309 for (edge = where->callers; edge; edge = edge->next_caller)
1310 if (edge->inline_failed)
1311 edge_growth_cache->remove (edge);
1313 FOR_EACH_ALIAS (where, ref)
1314 reset_edge_caches (dyn_cast <cgraph_node *> (ref->referring));
1316 if (!e)
1317 return;
1319 while (true)
1320 if (!e->inline_failed && e->callee->callees)
1321 e = e->callee->callees;
1322 else
1324 if (edge_growth_cache != NULL && e->inline_failed)
1325 edge_growth_cache->remove (e);
1326 if (e->next_callee)
1327 e = e->next_callee;
1328 else
1332 if (e->caller == node)
1333 return;
1334 e = e->caller->callers;
1336 while (!e->next_callee);
1337 e = e->next_callee;
1342 /* Recompute HEAP nodes for each of caller of NODE.
1343 UPDATED_NODES track nodes we already visited, to avoid redundant work.
1344 When CHECK_INLINABLITY_FOR is set, re-check for specified edge that
1345 it is inlinable. Otherwise check all edges. */
1347 static void
1348 update_caller_keys (edge_heap_t *heap, struct cgraph_node *node,
1349 bitmap updated_nodes,
1350 struct cgraph_edge *check_inlinablity_for)
1352 struct cgraph_edge *edge;
1353 struct ipa_ref *ref;
1355 if ((!node->alias && !ipa_fn_summaries->get (node)->inlinable)
1356 || node->global.inlined_to)
1357 return;
1358 if (!bitmap_set_bit (updated_nodes, node->get_uid ()))
1359 return;
1361 FOR_EACH_ALIAS (node, ref)
1363 struct cgraph_node *alias = dyn_cast <cgraph_node *> (ref->referring);
1364 update_caller_keys (heap, alias, updated_nodes, check_inlinablity_for);
1367 for (edge = node->callers; edge; edge = edge->next_caller)
1368 if (edge->inline_failed)
1370 if (!check_inlinablity_for
1371 || check_inlinablity_for == edge)
1373 if (can_inline_edge_p (edge, false)
1374 && want_inline_small_function_p (edge, false)
1375 && can_inline_edge_by_limits_p (edge, false))
1376 update_edge_key (heap, edge);
1377 else if (edge->aux)
1379 report_inline_failed_reason (edge);
1380 heap->delete_node ((edge_heap_node_t *) edge->aux);
1381 edge->aux = NULL;
1384 else if (edge->aux)
1385 update_edge_key (heap, edge);
1389 /* Recompute HEAP nodes for each uninlined call in NODE.
1390 This is used when we know that edge badnesses are going only to increase
1391 (we introduced new call site) and thus all we need is to insert newly
1392 created edges into heap. */
1394 static void
1395 update_callee_keys (edge_heap_t *heap, struct cgraph_node *node,
1396 bitmap updated_nodes)
1398 struct cgraph_edge *e = node->callees;
1400 if (!e)
1401 return;
1402 while (true)
1403 if (!e->inline_failed && e->callee->callees)
1404 e = e->callee->callees;
1405 else
1407 enum availability avail;
1408 struct cgraph_node *callee;
1409 /* We do not reset callee growth cache here. Since we added a new call,
1410 growth chould have just increased and consequentely badness metric
1411 don't need updating. */
1412 if (e->inline_failed
1413 && (callee = e->callee->ultimate_alias_target (&avail, e->caller))
1414 && ipa_fn_summaries->get (callee) != NULL
1415 && ipa_fn_summaries->get (callee)->inlinable
1416 && avail >= AVAIL_AVAILABLE
1417 && !bitmap_bit_p (updated_nodes, callee->get_uid ()))
1419 if (can_inline_edge_p (e, false)
1420 && want_inline_small_function_p (e, false)
1421 && can_inline_edge_by_limits_p (e, false))
1422 update_edge_key (heap, e);
1423 else if (e->aux)
1425 report_inline_failed_reason (e);
1426 heap->delete_node ((edge_heap_node_t *) e->aux);
1427 e->aux = NULL;
1430 if (e->next_callee)
1431 e = e->next_callee;
1432 else
1436 if (e->caller == node)
1437 return;
1438 e = e->caller->callers;
1440 while (!e->next_callee);
1441 e = e->next_callee;
1446 /* Enqueue all recursive calls from NODE into priority queue depending on
1447 how likely we want to recursively inline the call. */
1449 static void
1450 lookup_recursive_calls (struct cgraph_node *node, struct cgraph_node *where,
1451 edge_heap_t *heap)
1453 struct cgraph_edge *e;
1454 enum availability avail;
1456 for (e = where->callees; e; e = e->next_callee)
1457 if (e->callee == node
1458 || (e->callee->ultimate_alias_target (&avail, e->caller) == node
1459 && avail > AVAIL_INTERPOSABLE))
1460 heap->insert (-e->sreal_frequency (), e);
1461 for (e = where->callees; e; e = e->next_callee)
1462 if (!e->inline_failed)
1463 lookup_recursive_calls (node, e->callee, heap);
1466 /* Decide on recursive inlining: in the case function has recursive calls,
1467 inline until body size reaches given argument. If any new indirect edges
1468 are discovered in the process, add them to *NEW_EDGES, unless NEW_EDGES
1469 is NULL. */
1471 static bool
1472 recursive_inlining (struct cgraph_edge *edge,
1473 vec<cgraph_edge *> *new_edges)
1475 int limit = PARAM_VALUE (PARAM_MAX_INLINE_INSNS_RECURSIVE_AUTO);
1476 edge_heap_t heap (sreal::min ());
1477 struct cgraph_node *node;
1478 struct cgraph_edge *e;
1479 struct cgraph_node *master_clone = NULL, *next;
1480 int depth = 0;
1481 int n = 0;
1483 node = edge->caller;
1484 if (node->global.inlined_to)
1485 node = node->global.inlined_to;
1487 if (DECL_DECLARED_INLINE_P (node->decl))
1488 limit = PARAM_VALUE (PARAM_MAX_INLINE_INSNS_RECURSIVE);
1490 /* Make sure that function is small enough to be considered for inlining. */
1491 if (estimate_size_after_inlining (node, edge) >= limit)
1492 return false;
1493 lookup_recursive_calls (node, node, &heap);
1494 if (heap.empty ())
1495 return false;
1497 if (dump_file)
1498 fprintf (dump_file,
1499 " Performing recursive inlining on %s\n",
1500 node->name ());
1502 /* Do the inlining and update list of recursive call during process. */
1503 while (!heap.empty ())
1505 struct cgraph_edge *curr = heap.extract_min ();
1506 struct cgraph_node *cnode, *dest = curr->callee;
1508 if (!can_inline_edge_p (curr, true)
1509 || can_inline_edge_by_limits_p (curr, true))
1510 continue;
1512 /* MASTER_CLONE is produced in the case we already started modified
1513 the function. Be sure to redirect edge to the original body before
1514 estimating growths otherwise we will be seeing growths after inlining
1515 the already modified body. */
1516 if (master_clone)
1518 curr->redirect_callee (master_clone);
1519 if (edge_growth_cache != NULL)
1520 edge_growth_cache->remove (curr);
1523 if (estimate_size_after_inlining (node, curr) > limit)
1525 curr->redirect_callee (dest);
1526 if (edge_growth_cache != NULL)
1527 edge_growth_cache->remove (curr);
1528 break;
1531 depth = 1;
1532 for (cnode = curr->caller;
1533 cnode->global.inlined_to; cnode = cnode->callers->caller)
1534 if (node->decl
1535 == curr->callee->ultimate_alias_target ()->decl)
1536 depth++;
1538 if (!want_inline_self_recursive_call_p (curr, node, false, depth))
1540 curr->redirect_callee (dest);
1541 if (edge_growth_cache != NULL)
1542 edge_growth_cache->remove (curr);
1543 continue;
1546 if (dump_file)
1548 fprintf (dump_file,
1549 " Inlining call of depth %i", depth);
1550 if (node->count.nonzero_p ())
1552 fprintf (dump_file, " called approx. %.2f times per call",
1553 (double)curr->count.to_gcov_type ()
1554 / node->count.to_gcov_type ());
1556 fprintf (dump_file, "\n");
1558 if (!master_clone)
1560 /* We need original clone to copy around. */
1561 master_clone = node->create_clone (node->decl, node->count,
1562 false, vNULL, true, NULL, NULL);
1563 for (e = master_clone->callees; e; e = e->next_callee)
1564 if (!e->inline_failed)
1565 clone_inlined_nodes (e, true, false, NULL);
1566 curr->redirect_callee (master_clone);
1567 if (edge_growth_cache != NULL)
1568 edge_growth_cache->remove (curr);
1571 inline_call (curr, false, new_edges, &overall_size, true);
1572 lookup_recursive_calls (node, curr->callee, &heap);
1573 n++;
1576 if (!heap.empty () && dump_file)
1577 fprintf (dump_file, " Recursive inlining growth limit met.\n");
1579 if (!master_clone)
1580 return false;
1582 if (dump_enabled_p ())
1583 dump_printf_loc (MSG_NOTE, edge->call_stmt,
1584 "\n Inlined %i times, "
1585 "body grown from size %i to %i, time %f to %f\n", n,
1586 ipa_fn_summaries->get (master_clone)->size,
1587 ipa_fn_summaries->get (node)->size,
1588 ipa_fn_summaries->get (master_clone)->time.to_double (),
1589 ipa_fn_summaries->get (node)->time.to_double ());
1591 /* Remove master clone we used for inlining. We rely that clones inlined
1592 into master clone gets queued just before master clone so we don't
1593 need recursion. */
1594 for (node = symtab->first_function (); node != master_clone;
1595 node = next)
1597 next = symtab->next_function (node);
1598 if (node->global.inlined_to == master_clone)
1599 node->remove ();
1601 master_clone->remove ();
1602 return true;
1606 /* Given whole compilation unit estimate of INSNS, compute how large we can
1607 allow the unit to grow. */
1609 static int
1610 compute_max_insns (int insns)
1612 int max_insns = insns;
1613 if (max_insns < PARAM_VALUE (PARAM_LARGE_UNIT_INSNS))
1614 max_insns = PARAM_VALUE (PARAM_LARGE_UNIT_INSNS);
1616 return ((int64_t) max_insns
1617 * (100 + PARAM_VALUE (PARAM_INLINE_UNIT_GROWTH)) / 100);
1621 /* Compute badness of all edges in NEW_EDGES and add them to the HEAP. */
1623 static void
1624 add_new_edges_to_heap (edge_heap_t *heap, vec<cgraph_edge *> new_edges)
1626 while (new_edges.length () > 0)
1628 struct cgraph_edge *edge = new_edges.pop ();
1630 gcc_assert (!edge->aux);
1631 if (edge->inline_failed
1632 && can_inline_edge_p (edge, true)
1633 && want_inline_small_function_p (edge, true)
1634 && can_inline_edge_by_limits_p (edge, true))
1635 edge->aux = heap->insert (edge_badness (edge, false), edge);
1639 /* Remove EDGE from the fibheap. */
1641 static void
1642 heap_edge_removal_hook (struct cgraph_edge *e, void *data)
1644 if (e->aux)
1646 ((edge_heap_t *)data)->delete_node ((edge_heap_node_t *)e->aux);
1647 e->aux = NULL;
1651 /* Return true if speculation of edge E seems useful.
1652 If ANTICIPATE_INLINING is true, be conservative and hope that E
1653 may get inlined. */
1655 bool
1656 speculation_useful_p (struct cgraph_edge *e, bool anticipate_inlining)
1658 enum availability avail;
1659 struct cgraph_node *target = e->callee->ultimate_alias_target (&avail,
1660 e->caller);
1661 struct cgraph_edge *direct, *indirect;
1662 struct ipa_ref *ref;
1664 gcc_assert (e->speculative && !e->indirect_unknown_callee);
1666 if (!e->maybe_hot_p ())
1667 return false;
1669 /* See if IP optimizations found something potentially useful about the
1670 function. For now we look only for CONST/PURE flags. Almost everything
1671 else we propagate is useless. */
1672 if (avail >= AVAIL_AVAILABLE)
1674 int ecf_flags = flags_from_decl_or_type (target->decl);
1675 if (ecf_flags & ECF_CONST)
1677 e->speculative_call_info (direct, indirect, ref);
1678 if (!(indirect->indirect_info->ecf_flags & ECF_CONST))
1679 return true;
1681 else if (ecf_flags & ECF_PURE)
1683 e->speculative_call_info (direct, indirect, ref);
1684 if (!(indirect->indirect_info->ecf_flags & ECF_PURE))
1685 return true;
1688 /* If we did not managed to inline the function nor redirect
1689 to an ipa-cp clone (that are seen by having local flag set),
1690 it is probably pointless to inline it unless hardware is missing
1691 indirect call predictor. */
1692 if (!anticipate_inlining && e->inline_failed && !target->local.local)
1693 return false;
1694 /* For overwritable targets there is not much to do. */
1695 if (e->inline_failed
1696 && (!can_inline_edge_p (e, false)
1697 || !can_inline_edge_by_limits_p (e, false, true)))
1698 return false;
1699 /* OK, speculation seems interesting. */
1700 return true;
1703 /* We know that EDGE is not going to be inlined.
1704 See if we can remove speculation. */
1706 static void
1707 resolve_noninline_speculation (edge_heap_t *edge_heap, struct cgraph_edge *edge)
1709 if (edge->speculative && !speculation_useful_p (edge, false))
1711 struct cgraph_node *node = edge->caller;
1712 struct cgraph_node *where = node->global.inlined_to
1713 ? node->global.inlined_to : node;
1714 auto_bitmap updated_nodes;
1716 if (edge->count.ipa ().initialized_p ())
1717 spec_rem += edge->count.ipa ();
1718 edge->resolve_speculation ();
1719 reset_edge_caches (where);
1720 ipa_update_overall_fn_summary (where);
1721 update_caller_keys (edge_heap, where,
1722 updated_nodes, NULL);
1723 update_callee_keys (edge_heap, where,
1724 updated_nodes);
1728 /* Return true if NODE should be accounted for overall size estimate.
1729 Skip all nodes optimized for size so we can measure the growth of hot
1730 part of program no matter of the padding. */
1732 bool
1733 inline_account_function_p (struct cgraph_node *node)
1735 return (!DECL_EXTERNAL (node->decl)
1736 && !opt_for_fn (node->decl, optimize_size)
1737 && node->frequency != NODE_FREQUENCY_UNLIKELY_EXECUTED);
1740 /* Count number of callers of NODE and store it into DATA (that
1741 points to int. Worker for cgraph_for_node_and_aliases. */
1743 static bool
1744 sum_callers (struct cgraph_node *node, void *data)
1746 struct cgraph_edge *e;
1747 int *num_calls = (int *)data;
1749 for (e = node->callers; e; e = e->next_caller)
1750 (*num_calls)++;
1751 return false;
1754 /* We use greedy algorithm for inlining of small functions:
1755 All inline candidates are put into prioritized heap ordered in
1756 increasing badness.
1758 The inlining of small functions is bounded by unit growth parameters. */
1760 static void
1761 inline_small_functions (void)
1763 struct cgraph_node *node;
1764 struct cgraph_edge *edge;
1765 edge_heap_t edge_heap (sreal::min ());
1766 auto_bitmap updated_nodes;
1767 int min_size, max_size;
1768 auto_vec<cgraph_edge *> new_indirect_edges;
1769 int initial_size = 0;
1770 struct cgraph_node **order = XCNEWVEC (cgraph_node *, symtab->cgraph_count);
1771 struct cgraph_edge_hook_list *edge_removal_hook_holder;
1772 new_indirect_edges.create (8);
1774 edge_removal_hook_holder
1775 = symtab->add_edge_removal_hook (&heap_edge_removal_hook, &edge_heap);
1777 /* Compute overall unit size and other global parameters used by badness
1778 metrics. */
1780 max_count = profile_count::uninitialized ();
1781 ipa_reduced_postorder (order, true, NULL);
1782 free (order);
1784 FOR_EACH_DEFINED_FUNCTION (node)
1785 if (!node->global.inlined_to)
1787 if (!node->alias && node->analyzed
1788 && (node->has_gimple_body_p () || node->thunk.thunk_p)
1789 && opt_for_fn (node->decl, optimize))
1791 struct ipa_fn_summary *info = ipa_fn_summaries->get (node);
1792 struct ipa_dfs_info *dfs = (struct ipa_dfs_info *) node->aux;
1794 /* Do not account external functions, they will be optimized out
1795 if not inlined. Also only count the non-cold portion of program. */
1796 if (inline_account_function_p (node))
1797 initial_size += info->size;
1798 info->growth = estimate_growth (node);
1800 int num_calls = 0;
1801 node->call_for_symbol_and_aliases (sum_callers, &num_calls,
1802 true);
1803 if (num_calls == 1)
1804 info->single_caller = true;
1805 if (dfs && dfs->next_cycle)
1807 struct cgraph_node *n2;
1808 int id = dfs->scc_no + 1;
1809 for (n2 = node; n2;
1810 n2 = ((struct ipa_dfs_info *) n2->aux)->next_cycle)
1811 if (opt_for_fn (n2->decl, optimize))
1813 ipa_fn_summary *info2 = ipa_fn_summaries->get (n2);
1814 if (info2->scc_no)
1815 break;
1816 info2->scc_no = id;
1821 for (edge = node->callers; edge; edge = edge->next_caller)
1822 max_count = max_count.max (edge->count.ipa ());
1824 ipa_free_postorder_info ();
1825 edge_growth_cache
1826 = new call_summary<edge_growth_cache_entry *> (symtab, false);
1828 if (dump_file)
1829 fprintf (dump_file,
1830 "\nDeciding on inlining of small functions. Starting with size %i.\n",
1831 initial_size);
1833 overall_size = initial_size;
1834 max_size = compute_max_insns (overall_size);
1835 min_size = overall_size;
1837 /* Populate the heap with all edges we might inline. */
1839 FOR_EACH_DEFINED_FUNCTION (node)
1841 bool update = false;
1842 struct cgraph_edge *next = NULL;
1843 bool has_speculative = false;
1845 if (!opt_for_fn (node->decl, optimize))
1846 continue;
1848 if (dump_file)
1849 fprintf (dump_file, "Enqueueing calls in %s.\n", node->dump_name ());
1851 for (edge = node->callees; edge; edge = next)
1853 next = edge->next_callee;
1854 if (edge->inline_failed
1855 && !edge->aux
1856 && can_inline_edge_p (edge, true)
1857 && want_inline_small_function_p (edge, true)
1858 && can_inline_edge_by_limits_p (edge, true)
1859 && edge->inline_failed)
1861 gcc_assert (!edge->aux);
1862 update_edge_key (&edge_heap, edge);
1864 if (edge->speculative)
1865 has_speculative = true;
1867 if (has_speculative)
1868 for (edge = node->callees; edge; edge = next)
1869 if (edge->speculative && !speculation_useful_p (edge,
1870 edge->aux != NULL))
1872 edge->resolve_speculation ();
1873 update = true;
1875 if (update)
1877 struct cgraph_node *where = node->global.inlined_to
1878 ? node->global.inlined_to : node;
1879 ipa_update_overall_fn_summary (where);
1880 reset_edge_caches (where);
1881 update_caller_keys (&edge_heap, where,
1882 updated_nodes, NULL);
1883 update_callee_keys (&edge_heap, where,
1884 updated_nodes);
1885 bitmap_clear (updated_nodes);
1889 gcc_assert (in_lto_p
1890 || !(max_count > 0)
1891 || (profile_info && flag_branch_probabilities));
1893 while (!edge_heap.empty ())
1895 int old_size = overall_size;
1896 struct cgraph_node *where, *callee;
1897 sreal badness = edge_heap.min_key ();
1898 sreal current_badness;
1899 int growth;
1901 edge = edge_heap.extract_min ();
1902 gcc_assert (edge->aux);
1903 edge->aux = NULL;
1904 if (!edge->inline_failed || !edge->callee->analyzed)
1905 continue;
1907 #if CHECKING_P
1908 /* Be sure that caches are maintained consistent.
1909 This check is affected by scaling roundoff errors when compiling for
1910 IPA this we skip it in that case. */
1911 if (!edge->callee->count.ipa_p ()
1912 && (!max_count.initialized_p () || !max_count.nonzero_p ()))
1914 sreal cached_badness = edge_badness (edge, false);
1916 int old_size_est = estimate_edge_size (edge);
1917 sreal old_time_est = estimate_edge_time (edge);
1918 int old_hints_est = estimate_edge_hints (edge);
1920 if (edge_growth_cache != NULL)
1921 edge_growth_cache->remove (edge);
1922 gcc_assert (old_size_est == estimate_edge_size (edge));
1923 gcc_assert (old_time_est == estimate_edge_time (edge));
1924 /* FIXME:
1926 gcc_assert (old_hints_est == estimate_edge_hints (edge));
1928 fails with profile feedback because some hints depends on
1929 maybe_hot_edge_p predicate and because callee gets inlined to other
1930 calls, the edge may become cold.
1931 This ought to be fixed by computing relative probabilities
1932 for given invocation but that will be better done once whole
1933 code is converted to sreals. Disable for now and revert to "wrong"
1934 value so enable/disable checking paths agree. */
1935 edge_growth_cache->get (edge)->hints = old_hints_est + 1;
1937 /* When updating the edge costs, we only decrease badness in the keys.
1938 Increases of badness are handled lazilly; when we see key with out
1939 of date value on it, we re-insert it now. */
1940 current_badness = edge_badness (edge, false);
1941 gcc_assert (cached_badness == current_badness);
1942 gcc_assert (current_badness >= badness);
1944 else
1945 current_badness = edge_badness (edge, false);
1946 #else
1947 current_badness = edge_badness (edge, false);
1948 #endif
1949 if (current_badness != badness)
1951 if (edge_heap.min () && current_badness > edge_heap.min_key ())
1953 edge->aux = edge_heap.insert (current_badness, edge);
1954 continue;
1956 else
1957 badness = current_badness;
1960 if (!can_inline_edge_p (edge, true)
1961 || !can_inline_edge_by_limits_p (edge, true))
1963 resolve_noninline_speculation (&edge_heap, edge);
1964 continue;
1967 callee = edge->callee->ultimate_alias_target ();
1968 growth = estimate_edge_growth (edge);
1969 if (dump_file)
1971 fprintf (dump_file,
1972 "\nConsidering %s with %i size\n",
1973 callee->dump_name (),
1974 ipa_fn_summaries->get (callee)->size);
1975 fprintf (dump_file,
1976 " to be inlined into %s in %s:%i\n"
1977 " Estimated badness is %f, frequency %.2f.\n",
1978 edge->caller->dump_name (),
1979 edge->call_stmt
1980 && (LOCATION_LOCUS (gimple_location ((const gimple *)
1981 edge->call_stmt))
1982 > BUILTINS_LOCATION)
1983 ? gimple_filename ((const gimple *) edge->call_stmt)
1984 : "unknown",
1985 edge->call_stmt
1986 ? gimple_lineno ((const gimple *) edge->call_stmt)
1987 : -1,
1988 badness.to_double (),
1989 edge->sreal_frequency ().to_double ());
1990 if (edge->count.ipa ().initialized_p ())
1992 fprintf (dump_file, " Called ");
1993 edge->count.ipa ().dump (dump_file);
1994 fprintf (dump_file, " times\n");
1996 if (dump_flags & TDF_DETAILS)
1997 edge_badness (edge, true);
2000 if (overall_size + growth > max_size
2001 && !DECL_DISREGARD_INLINE_LIMITS (callee->decl))
2003 edge->inline_failed = CIF_INLINE_UNIT_GROWTH_LIMIT;
2004 report_inline_failed_reason (edge);
2005 resolve_noninline_speculation (&edge_heap, edge);
2006 continue;
2009 if (!want_inline_small_function_p (edge, true))
2011 resolve_noninline_speculation (&edge_heap, edge);
2012 continue;
2015 /* Heuristics for inlining small functions work poorly for
2016 recursive calls where we do effects similar to loop unrolling.
2017 When inlining such edge seems profitable, leave decision on
2018 specific inliner. */
2019 if (edge->recursive_p ())
2021 where = edge->caller;
2022 if (where->global.inlined_to)
2023 where = where->global.inlined_to;
2024 if (!recursive_inlining (edge,
2025 opt_for_fn (edge->caller->decl,
2026 flag_indirect_inlining)
2027 ? &new_indirect_edges : NULL))
2029 edge->inline_failed = CIF_RECURSIVE_INLINING;
2030 resolve_noninline_speculation (&edge_heap, edge);
2031 continue;
2033 reset_edge_caches (where);
2034 /* Recursive inliner inlines all recursive calls of the function
2035 at once. Consequently we need to update all callee keys. */
2036 if (opt_for_fn (edge->caller->decl, flag_indirect_inlining))
2037 add_new_edges_to_heap (&edge_heap, new_indirect_edges);
2038 update_callee_keys (&edge_heap, where, updated_nodes);
2039 bitmap_clear (updated_nodes);
2041 else
2043 struct cgraph_node *outer_node = NULL;
2044 int depth = 0;
2046 /* Consider the case where self recursive function A is inlined
2047 into B. This is desired optimization in some cases, since it
2048 leads to effect similar of loop peeling and we might completely
2049 optimize out the recursive call. However we must be extra
2050 selective. */
2052 where = edge->caller;
2053 while (where->global.inlined_to)
2055 if (where->decl == callee->decl)
2056 outer_node = where, depth++;
2057 where = where->callers->caller;
2059 if (outer_node
2060 && !want_inline_self_recursive_call_p (edge, outer_node,
2061 true, depth))
2063 edge->inline_failed
2064 = (DECL_DISREGARD_INLINE_LIMITS (edge->callee->decl)
2065 ? CIF_RECURSIVE_INLINING : CIF_UNSPECIFIED);
2066 resolve_noninline_speculation (&edge_heap, edge);
2067 continue;
2069 else if (depth && dump_file)
2070 fprintf (dump_file, " Peeling recursion with depth %i\n", depth);
2072 gcc_checking_assert (!callee->global.inlined_to);
2073 inline_call (edge, true, &new_indirect_edges, &overall_size, true);
2074 add_new_edges_to_heap (&edge_heap, new_indirect_edges);
2076 reset_edge_caches (edge->callee);
2078 update_callee_keys (&edge_heap, where, updated_nodes);
2080 where = edge->caller;
2081 if (where->global.inlined_to)
2082 where = where->global.inlined_to;
2084 /* Our profitability metric can depend on local properties
2085 such as number of inlinable calls and size of the function body.
2086 After inlining these properties might change for the function we
2087 inlined into (since it's body size changed) and for the functions
2088 called by function we inlined (since number of it inlinable callers
2089 might change). */
2090 update_caller_keys (&edge_heap, where, updated_nodes, NULL);
2091 /* Offline copy count has possibly changed, recompute if profile is
2092 available. */
2093 struct cgraph_node *n = cgraph_node::get (edge->callee->decl);
2094 if (n != edge->callee && n->analyzed && n->count.ipa ().initialized_p ())
2095 update_callee_keys (&edge_heap, n, updated_nodes);
2096 bitmap_clear (updated_nodes);
2098 if (dump_enabled_p ())
2100 ipa_fn_summary *s = ipa_fn_summaries->get (edge->caller);
2102 /* dump_printf can't handle %+i. */
2103 char buf_net_change[100];
2104 snprintf (buf_net_change, sizeof buf_net_change, "%+i",
2105 overall_size - old_size);
2107 dump_printf_loc (MSG_OPTIMIZED_LOCATIONS, edge->call_stmt,
2108 " Inlined %C into %C which now has time %f and "
2109 "size %i, net change of %s.\n",
2110 edge->callee, edge->caller,
2111 s->time.to_double (), s->size, buf_net_change);
2113 if (min_size > overall_size)
2115 min_size = overall_size;
2116 max_size = compute_max_insns (min_size);
2118 if (dump_file)
2119 fprintf (dump_file, "New minimal size reached: %i\n", min_size);
2123 free_growth_caches ();
2124 if (dump_enabled_p ())
2125 dump_printf (MSG_NOTE,
2126 "Unit growth for small function inlining: %i->%i (%i%%)\n",
2127 initial_size, overall_size,
2128 initial_size ? overall_size * 100 / (initial_size) - 100: 0);
2129 symtab->remove_edge_removal_hook (edge_removal_hook_holder);
2132 /* Flatten NODE. Performed both during early inlining and
2133 at IPA inlining time. */
2135 static void
2136 flatten_function (struct cgraph_node *node, bool early)
2138 struct cgraph_edge *e;
2140 /* We shouldn't be called recursively when we are being processed. */
2141 gcc_assert (node->aux == NULL);
2143 node->aux = (void *) node;
2145 for (e = node->callees; e; e = e->next_callee)
2147 struct cgraph_node *orig_callee;
2148 struct cgraph_node *callee = e->callee->ultimate_alias_target ();
2150 /* We've hit cycle? It is time to give up. */
2151 if (callee->aux)
2153 if (dump_enabled_p ())
2154 dump_printf_loc (MSG_MISSED_OPTIMIZATION, e->call_stmt,
2155 "Not inlining %C into %C to avoid cycle.\n",
2156 callee, e->caller);
2157 if (cgraph_inline_failed_type (e->inline_failed) != CIF_FINAL_ERROR)
2158 e->inline_failed = CIF_RECURSIVE_INLINING;
2159 continue;
2162 /* When the edge is already inlined, we just need to recurse into
2163 it in order to fully flatten the leaves. */
2164 if (!e->inline_failed)
2166 flatten_function (callee, early);
2167 continue;
2170 /* Flatten attribute needs to be processed during late inlining. For
2171 extra code quality we however do flattening during early optimization,
2172 too. */
2173 if (!early
2174 ? !can_inline_edge_p (e, true)
2175 && !can_inline_edge_by_limits_p (e, true)
2176 : !can_early_inline_edge_p (e))
2177 continue;
2179 if (e->recursive_p ())
2181 if (dump_enabled_p ())
2182 dump_printf_loc (MSG_MISSED_OPTIMIZATION, e->call_stmt,
2183 "Not inlining: recursive call.\n");
2184 continue;
2187 if (gimple_in_ssa_p (DECL_STRUCT_FUNCTION (node->decl))
2188 != gimple_in_ssa_p (DECL_STRUCT_FUNCTION (callee->decl)))
2190 if (dump_enabled_p ())
2191 dump_printf_loc (MSG_MISSED_OPTIMIZATION, e->call_stmt,
2192 "Not inlining: SSA form does not match.\n");
2193 continue;
2196 /* Inline the edge and flatten the inline clone. Avoid
2197 recursing through the original node if the node was cloned. */
2198 if (dump_enabled_p ())
2199 dump_printf_loc (MSG_OPTIMIZED_LOCATIONS, e->call_stmt,
2200 " Inlining %C into %C.\n",
2201 callee, e->caller);
2202 orig_callee = callee;
2203 inline_call (e, true, NULL, NULL, false);
2204 if (e->callee != orig_callee)
2205 orig_callee->aux = (void *) node;
2206 flatten_function (e->callee, early);
2207 if (e->callee != orig_callee)
2208 orig_callee->aux = NULL;
2211 node->aux = NULL;
2212 if (!node->global.inlined_to)
2213 ipa_update_overall_fn_summary (node);
2216 /* Inline NODE to all callers. Worker for cgraph_for_node_and_aliases.
2217 DATA points to number of calls originally found so we avoid infinite
2218 recursion. */
2220 static bool
2221 inline_to_all_callers_1 (struct cgraph_node *node, void *data,
2222 hash_set<cgraph_node *> *callers)
2224 int *num_calls = (int *)data;
2225 bool callee_removed = false;
2227 while (node->callers && !node->global.inlined_to)
2229 struct cgraph_node *caller = node->callers->caller;
2231 if (!can_inline_edge_p (node->callers, true)
2232 || !can_inline_edge_by_limits_p (node->callers, true)
2233 || node->callers->recursive_p ())
2235 if (dump_file)
2236 fprintf (dump_file, "Uninlinable call found; giving up.\n");
2237 *num_calls = 0;
2238 return false;
2241 if (dump_file)
2243 cgraph_node *ultimate = node->ultimate_alias_target ();
2244 fprintf (dump_file,
2245 "\nInlining %s size %i.\n",
2246 ultimate->name (),
2247 ipa_fn_summaries->get (ultimate)->size);
2248 fprintf (dump_file,
2249 " Called once from %s %i insns.\n",
2250 node->callers->caller->name (),
2251 ipa_fn_summaries->get (node->callers->caller)->size);
2254 /* Remember which callers we inlined to, delaying updating the
2255 overall summary. */
2256 callers->add (node->callers->caller);
2257 inline_call (node->callers, true, NULL, NULL, false, &callee_removed);
2258 if (dump_file)
2259 fprintf (dump_file,
2260 " Inlined into %s which now has %i size\n",
2261 caller->name (),
2262 ipa_fn_summaries->get (caller)->size);
2263 if (!(*num_calls)--)
2265 if (dump_file)
2266 fprintf (dump_file, "New calls found; giving up.\n");
2267 return callee_removed;
2269 if (callee_removed)
2270 return true;
2272 return false;
2275 /* Wrapper around inline_to_all_callers_1 doing delayed overall summary
2276 update. */
2278 static bool
2279 inline_to_all_callers (struct cgraph_node *node, void *data)
2281 hash_set<cgraph_node *> callers;
2282 bool res = inline_to_all_callers_1 (node, data, &callers);
2283 /* Perform the delayed update of the overall summary of all callers
2284 processed. This avoids quadratic behavior in the cases where
2285 we have a lot of calls to the same function. */
2286 for (hash_set<cgraph_node *>::iterator i = callers.begin ();
2287 i != callers.end (); ++i)
2288 ipa_update_overall_fn_summary (*i);
2289 return res;
2292 /* Output overall time estimate. */
2293 static void
2294 dump_overall_stats (void)
2296 sreal sum_weighted = 0, sum = 0;
2297 struct cgraph_node *node;
2299 FOR_EACH_DEFINED_FUNCTION (node)
2300 if (!node->global.inlined_to
2301 && !node->alias)
2303 ipa_fn_summary *s = ipa_fn_summaries->get (node);
2304 if (s != NULL)
2306 sum += s->time;
2307 if (node->count.ipa ().initialized_p ())
2308 sum_weighted += s->time * node->count.ipa ().to_gcov_type ();
2311 fprintf (dump_file, "Overall time estimate: "
2312 "%f weighted by profile: "
2313 "%f\n", sum.to_double (), sum_weighted.to_double ());
2316 /* Output some useful stats about inlining. */
2318 static void
2319 dump_inline_stats (void)
2321 int64_t inlined_cnt = 0, inlined_indir_cnt = 0;
2322 int64_t inlined_virt_cnt = 0, inlined_virt_indir_cnt = 0;
2323 int64_t noninlined_cnt = 0, noninlined_indir_cnt = 0;
2324 int64_t noninlined_virt_cnt = 0, noninlined_virt_indir_cnt = 0;
2325 int64_t inlined_speculative = 0, inlined_speculative_ply = 0;
2326 int64_t indirect_poly_cnt = 0, indirect_cnt = 0;
2327 int64_t reason[CIF_N_REASONS][2];
2328 sreal reason_freq[CIF_N_REASONS];
2329 int i;
2330 struct cgraph_node *node;
2332 memset (reason, 0, sizeof (reason));
2333 for (i=0; i < CIF_N_REASONS; i++)
2334 reason_freq[i] = 0;
2335 FOR_EACH_DEFINED_FUNCTION (node)
2337 struct cgraph_edge *e;
2338 for (e = node->callees; e; e = e->next_callee)
2340 if (e->inline_failed)
2342 if (e->count.ipa ().initialized_p ())
2343 reason[(int) e->inline_failed][0] += e->count.ipa ().to_gcov_type ();
2344 reason_freq[(int) e->inline_failed] += e->sreal_frequency ();
2345 reason[(int) e->inline_failed][1] ++;
2346 if (DECL_VIRTUAL_P (e->callee->decl)
2347 && e->count.ipa ().initialized_p ())
2349 if (e->indirect_inlining_edge)
2350 noninlined_virt_indir_cnt += e->count.ipa ().to_gcov_type ();
2351 else
2352 noninlined_virt_cnt += e->count.ipa ().to_gcov_type ();
2354 else if (e->count.ipa ().initialized_p ())
2356 if (e->indirect_inlining_edge)
2357 noninlined_indir_cnt += e->count.ipa ().to_gcov_type ();
2358 else
2359 noninlined_cnt += e->count.ipa ().to_gcov_type ();
2362 else if (e->count.ipa ().initialized_p ())
2364 if (e->speculative)
2366 if (DECL_VIRTUAL_P (e->callee->decl))
2367 inlined_speculative_ply += e->count.ipa ().to_gcov_type ();
2368 else
2369 inlined_speculative += e->count.ipa ().to_gcov_type ();
2371 else if (DECL_VIRTUAL_P (e->callee->decl))
2373 if (e->indirect_inlining_edge)
2374 inlined_virt_indir_cnt += e->count.ipa ().to_gcov_type ();
2375 else
2376 inlined_virt_cnt += e->count.ipa ().to_gcov_type ();
2378 else
2380 if (e->indirect_inlining_edge)
2381 inlined_indir_cnt += e->count.ipa ().to_gcov_type ();
2382 else
2383 inlined_cnt += e->count.ipa ().to_gcov_type ();
2387 for (e = node->indirect_calls; e; e = e->next_callee)
2388 if (e->indirect_info->polymorphic
2389 & e->count.ipa ().initialized_p ())
2390 indirect_poly_cnt += e->count.ipa ().to_gcov_type ();
2391 else if (e->count.ipa ().initialized_p ())
2392 indirect_cnt += e->count.ipa ().to_gcov_type ();
2394 if (max_count.initialized_p ())
2396 fprintf (dump_file,
2397 "Inlined %" PRId64 " + speculative "
2398 "%" PRId64 " + speculative polymorphic "
2399 "%" PRId64 " + previously indirect "
2400 "%" PRId64 " + virtual "
2401 "%" PRId64 " + virtual and previously indirect "
2402 "%" PRId64 "\n" "Not inlined "
2403 "%" PRId64 " + previously indirect "
2404 "%" PRId64 " + virtual "
2405 "%" PRId64 " + virtual and previously indirect "
2406 "%" PRId64 " + stil indirect "
2407 "%" PRId64 " + still indirect polymorphic "
2408 "%" PRId64 "\n", inlined_cnt,
2409 inlined_speculative, inlined_speculative_ply,
2410 inlined_indir_cnt, inlined_virt_cnt, inlined_virt_indir_cnt,
2411 noninlined_cnt, noninlined_indir_cnt, noninlined_virt_cnt,
2412 noninlined_virt_indir_cnt, indirect_cnt, indirect_poly_cnt);
2413 fprintf (dump_file, "Removed speculations ");
2414 spec_rem.dump (dump_file);
2415 fprintf (dump_file, "\n");
2417 dump_overall_stats ();
2418 fprintf (dump_file, "\nWhy inlining failed?\n");
2419 for (i = 0; i < CIF_N_REASONS; i++)
2420 if (reason[i][1])
2421 fprintf (dump_file, "%-50s: %8i calls, %8f freq, %" PRId64" count\n",
2422 cgraph_inline_failed_string ((cgraph_inline_failed_t) i),
2423 (int) reason[i][1], reason_freq[i].to_double (), reason[i][0]);
2426 /* Called when node is removed. */
2428 static void
2429 flatten_remove_node_hook (struct cgraph_node *node, void *data)
2431 if (lookup_attribute ("flatten", DECL_ATTRIBUTES (node->decl)) == NULL)
2432 return;
2434 hash_set<struct cgraph_node *> *removed
2435 = (hash_set<struct cgraph_node *> *) data;
2436 removed->add (node);
2439 /* Decide on the inlining. We do so in the topological order to avoid
2440 expenses on updating data structures. */
2442 static unsigned int
2443 ipa_inline (void)
2445 struct cgraph_node *node;
2446 int nnodes;
2447 struct cgraph_node **order;
2448 int i, j;
2449 int cold;
2450 bool remove_functions = false;
2452 order = XCNEWVEC (struct cgraph_node *, symtab->cgraph_count);
2454 if (dump_file)
2455 ipa_dump_fn_summaries (dump_file);
2457 nnodes = ipa_reverse_postorder (order);
2458 spec_rem = profile_count::zero ();
2460 FOR_EACH_FUNCTION (node)
2462 node->aux = 0;
2464 /* Recompute the default reasons for inlining because they may have
2465 changed during merging. */
2466 if (in_lto_p)
2468 for (cgraph_edge *e = node->callees; e; e = e->next_callee)
2470 gcc_assert (e->inline_failed);
2471 initialize_inline_failed (e);
2473 for (cgraph_edge *e = node->indirect_calls; e; e = e->next_callee)
2474 initialize_inline_failed (e);
2478 if (dump_file)
2479 fprintf (dump_file, "\nFlattening functions:\n");
2481 /* First shrink order array, so that it only contains nodes with
2482 flatten attribute. */
2483 for (i = nnodes - 1, j = i; i >= 0; i--)
2485 node = order[i];
2486 if (lookup_attribute ("flatten",
2487 DECL_ATTRIBUTES (node->decl)) != NULL)
2488 order[j--] = order[i];
2491 /* After the above loop, order[j + 1] ... order[nnodes - 1] contain
2492 nodes with flatten attribute. If there is more than one such
2493 node, we need to register a node removal hook, as flatten_function
2494 could remove other nodes with flatten attribute. See PR82801. */
2495 struct cgraph_node_hook_list *node_removal_hook_holder = NULL;
2496 hash_set<struct cgraph_node *> *flatten_removed_nodes = NULL;
2497 if (j < nnodes - 2)
2499 flatten_removed_nodes = new hash_set<struct cgraph_node *>;
2500 node_removal_hook_holder
2501 = symtab->add_cgraph_removal_hook (&flatten_remove_node_hook,
2502 flatten_removed_nodes);
2505 /* In the first pass handle functions to be flattened. Do this with
2506 a priority so none of our later choices will make this impossible. */
2507 for (i = nnodes - 1; i > j; i--)
2509 node = order[i];
2510 if (flatten_removed_nodes
2511 && flatten_removed_nodes->contains (node))
2512 continue;
2514 /* Handle nodes to be flattened.
2515 Ideally when processing callees we stop inlining at the
2516 entry of cycles, possibly cloning that entry point and
2517 try to flatten itself turning it into a self-recursive
2518 function. */
2519 if (dump_file)
2520 fprintf (dump_file, "Flattening %s\n", node->name ());
2521 flatten_function (node, false);
2524 if (j < nnodes - 2)
2526 symtab->remove_cgraph_removal_hook (node_removal_hook_holder);
2527 delete flatten_removed_nodes;
2529 free (order);
2531 if (dump_file)
2532 dump_overall_stats ();
2534 inline_small_functions ();
2536 gcc_assert (symtab->state == IPA_SSA);
2537 symtab->state = IPA_SSA_AFTER_INLINING;
2538 /* Do first after-inlining removal. We want to remove all "stale" extern
2539 inline functions and virtual functions so we really know what is called
2540 once. */
2541 symtab->remove_unreachable_nodes (dump_file);
2543 /* Inline functions with a property that after inlining into all callers the
2544 code size will shrink because the out-of-line copy is eliminated.
2545 We do this regardless on the callee size as long as function growth limits
2546 are met. */
2547 if (dump_file)
2548 fprintf (dump_file,
2549 "\nDeciding on functions to be inlined into all callers and "
2550 "removing useless speculations:\n");
2552 /* Inlining one function called once has good chance of preventing
2553 inlining other function into the same callee. Ideally we should
2554 work in priority order, but probably inlining hot functions first
2555 is good cut without the extra pain of maintaining the queue.
2557 ??? this is not really fitting the bill perfectly: inlining function
2558 into callee often leads to better optimization of callee due to
2559 increased context for optimization.
2560 For example if main() function calls a function that outputs help
2561 and then function that does the main optmization, we should inline
2562 the second with priority even if both calls are cold by themselves.
2564 We probably want to implement new predicate replacing our use of
2565 maybe_hot_edge interpreted as maybe_hot_edge || callee is known
2566 to be hot. */
2567 for (cold = 0; cold <= 1; cold ++)
2569 FOR_EACH_DEFINED_FUNCTION (node)
2571 struct cgraph_edge *edge, *next;
2572 bool update=false;
2574 if (!opt_for_fn (node->decl, optimize)
2575 || !opt_for_fn (node->decl, flag_inline_functions_called_once))
2576 continue;
2578 for (edge = node->callees; edge; edge = next)
2580 next = edge->next_callee;
2581 if (edge->speculative && !speculation_useful_p (edge, false))
2583 if (edge->count.ipa ().initialized_p ())
2584 spec_rem += edge->count.ipa ();
2585 edge->resolve_speculation ();
2586 update = true;
2587 remove_functions = true;
2590 if (update)
2592 struct cgraph_node *where = node->global.inlined_to
2593 ? node->global.inlined_to : node;
2594 reset_edge_caches (where);
2595 ipa_update_overall_fn_summary (where);
2597 if (want_inline_function_to_all_callers_p (node, cold))
2599 int num_calls = 0;
2600 node->call_for_symbol_and_aliases (sum_callers, &num_calls,
2601 true);
2602 while (node->call_for_symbol_and_aliases
2603 (inline_to_all_callers, &num_calls, true))
2605 remove_functions = true;
2610 /* Free ipa-prop structures if they are no longer needed. */
2611 ipa_free_all_structures_after_iinln ();
2613 if (dump_enabled_p ())
2614 dump_printf (MSG_NOTE,
2615 "\nInlined %i calls, eliminated %i functions\n\n",
2616 ncalls_inlined, nfunctions_inlined);
2617 if (dump_file)
2618 dump_inline_stats ();
2620 if (dump_file)
2621 ipa_dump_fn_summaries (dump_file);
2622 return remove_functions ? TODO_remove_functions : 0;
2625 /* Inline always-inline function calls in NODE. */
2627 static bool
2628 inline_always_inline_functions (struct cgraph_node *node)
2630 struct cgraph_edge *e;
2631 bool inlined = false;
2633 for (e = node->callees; e; e = e->next_callee)
2635 struct cgraph_node *callee = e->callee->ultimate_alias_target ();
2636 if (!DECL_DISREGARD_INLINE_LIMITS (callee->decl))
2637 continue;
2639 if (e->recursive_p ())
2641 if (dump_enabled_p ())
2642 dump_printf_loc (MSG_MISSED_OPTIMIZATION, e->call_stmt,
2643 " Not inlining recursive call to %C.\n",
2644 e->callee);
2645 e->inline_failed = CIF_RECURSIVE_INLINING;
2646 continue;
2649 if (!can_early_inline_edge_p (e))
2651 /* Set inlined to true if the callee is marked "always_inline" but
2652 is not inlinable. This will allow flagging an error later in
2653 expand_call_inline in tree-inline.c. */
2654 if (lookup_attribute ("always_inline",
2655 DECL_ATTRIBUTES (callee->decl)) != NULL)
2656 inlined = true;
2657 continue;
2660 if (dump_enabled_p ())
2661 dump_printf_loc (MSG_OPTIMIZED_LOCATIONS, e->call_stmt,
2662 " Inlining %C into %C (always_inline).\n",
2663 e->callee, e->caller);
2664 inline_call (e, true, NULL, NULL, false);
2665 inlined = true;
2667 if (inlined)
2668 ipa_update_overall_fn_summary (node);
2670 return inlined;
2673 /* Decide on the inlining. We do so in the topological order to avoid
2674 expenses on updating data structures. */
2676 static bool
2677 early_inline_small_functions (struct cgraph_node *node)
2679 struct cgraph_edge *e;
2680 bool inlined = false;
2682 for (e = node->callees; e; e = e->next_callee)
2684 struct cgraph_node *callee = e->callee->ultimate_alias_target ();
2686 /* We can enounter not-yet-analyzed function during
2687 early inlining on callgraphs with strongly
2688 connected components. */
2689 ipa_fn_summary *s = ipa_fn_summaries->get (callee);
2690 if (s == NULL || !s->inlinable || !e->inline_failed)
2691 continue;
2693 /* Do not consider functions not declared inline. */
2694 if (!DECL_DECLARED_INLINE_P (callee->decl)
2695 && !opt_for_fn (node->decl, flag_inline_small_functions)
2696 && !opt_for_fn (node->decl, flag_inline_functions))
2697 continue;
2699 if (dump_enabled_p ())
2700 dump_printf_loc (MSG_NOTE, e->call_stmt,
2701 "Considering inline candidate %C.\n",
2702 callee);
2704 if (!can_early_inline_edge_p (e))
2705 continue;
2707 if (e->recursive_p ())
2709 if (dump_enabled_p ())
2710 dump_printf_loc (MSG_MISSED_OPTIMIZATION, e->call_stmt,
2711 " Not inlining: recursive call.\n");
2712 continue;
2715 if (!want_early_inline_function_p (e))
2716 continue;
2718 if (dump_enabled_p ())
2719 dump_printf_loc (MSG_OPTIMIZED_LOCATIONS, e->call_stmt,
2720 " Inlining %C into %C.\n",
2721 callee, e->caller);
2722 inline_call (e, true, NULL, NULL, false);
2723 inlined = true;
2726 if (inlined)
2727 ipa_update_overall_fn_summary (node);
2729 return inlined;
2732 unsigned int
2733 early_inliner (function *fun)
2735 struct cgraph_node *node = cgraph_node::get (current_function_decl);
2736 struct cgraph_edge *edge;
2737 unsigned int todo = 0;
2738 int iterations = 0;
2739 bool inlined = false;
2741 if (seen_error ())
2742 return 0;
2744 /* Do nothing if datastructures for ipa-inliner are already computed. This
2745 happens when some pass decides to construct new function and
2746 cgraph_add_new_function calls lowering passes and early optimization on
2747 it. This may confuse ourself when early inliner decide to inline call to
2748 function clone, because function clones don't have parameter list in
2749 ipa-prop matching their signature. */
2750 if (ipa_node_params_sum)
2751 return 0;
2753 if (flag_checking)
2754 node->verify ();
2755 node->remove_all_references ();
2757 /* Even when not optimizing or not inlining inline always-inline
2758 functions. */
2759 inlined = inline_always_inline_functions (node);
2761 if (!optimize
2762 || flag_no_inline
2763 || !flag_early_inlining
2764 /* Never inline regular functions into always-inline functions
2765 during incremental inlining. This sucks as functions calling
2766 always inline functions will get less optimized, but at the
2767 same time inlining of functions calling always inline
2768 function into an always inline function might introduce
2769 cycles of edges to be always inlined in the callgraph.
2771 We might want to be smarter and just avoid this type of inlining. */
2772 || (DECL_DISREGARD_INLINE_LIMITS (node->decl)
2773 && lookup_attribute ("always_inline",
2774 DECL_ATTRIBUTES (node->decl))))
2776 else if (lookup_attribute ("flatten",
2777 DECL_ATTRIBUTES (node->decl)) != NULL)
2779 /* When the function is marked to be flattened, recursively inline
2780 all calls in it. */
2781 if (dump_enabled_p ())
2782 dump_printf (MSG_OPTIMIZED_LOCATIONS,
2783 "Flattening %C\n", node);
2784 flatten_function (node, true);
2785 inlined = true;
2787 else
2789 /* If some always_inline functions was inlined, apply the changes.
2790 This way we will not account always inline into growth limits and
2791 moreover we will inline calls from always inlines that we skipped
2792 previously because of conditional above. */
2793 if (inlined)
2795 timevar_push (TV_INTEGRATION);
2796 todo |= optimize_inline_calls (current_function_decl);
2797 /* optimize_inline_calls call above might have introduced new
2798 statements that don't have inline parameters computed. */
2799 for (edge = node->callees; edge; edge = edge->next_callee)
2801 /* We can enounter not-yet-analyzed function during
2802 early inlining on callgraphs with strongly
2803 connected components. */
2804 ipa_call_summary *es = ipa_call_summaries->get_create (edge);
2805 es->call_stmt_size
2806 = estimate_num_insns (edge->call_stmt, &eni_size_weights);
2807 es->call_stmt_time
2808 = estimate_num_insns (edge->call_stmt, &eni_time_weights);
2810 ipa_update_overall_fn_summary (node);
2811 inlined = false;
2812 timevar_pop (TV_INTEGRATION);
2814 /* We iterate incremental inlining to get trivial cases of indirect
2815 inlining. */
2816 while (iterations < PARAM_VALUE (PARAM_EARLY_INLINER_MAX_ITERATIONS)
2817 && early_inline_small_functions (node))
2819 timevar_push (TV_INTEGRATION);
2820 todo |= optimize_inline_calls (current_function_decl);
2822 /* Technically we ought to recompute inline parameters so the new
2823 iteration of early inliner works as expected. We however have
2824 values approximately right and thus we only need to update edge
2825 info that might be cleared out for newly discovered edges. */
2826 for (edge = node->callees; edge; edge = edge->next_callee)
2828 /* We have no summary for new bound store calls yet. */
2829 ipa_call_summary *es = ipa_call_summaries->get_create (edge);
2830 es->call_stmt_size
2831 = estimate_num_insns (edge->call_stmt, &eni_size_weights);
2832 es->call_stmt_time
2833 = estimate_num_insns (edge->call_stmt, &eni_time_weights);
2835 if (edge->callee->decl
2836 && !gimple_check_call_matching_types (
2837 edge->call_stmt, edge->callee->decl, false))
2839 edge->inline_failed = CIF_MISMATCHED_ARGUMENTS;
2840 edge->call_stmt_cannot_inline_p = true;
2843 if (iterations < PARAM_VALUE (PARAM_EARLY_INLINER_MAX_ITERATIONS) - 1)
2844 ipa_update_overall_fn_summary (node);
2845 timevar_pop (TV_INTEGRATION);
2846 iterations++;
2847 inlined = false;
2849 if (dump_file)
2850 fprintf (dump_file, "Iterations: %i\n", iterations);
2853 if (inlined)
2855 timevar_push (TV_INTEGRATION);
2856 todo |= optimize_inline_calls (current_function_decl);
2857 timevar_pop (TV_INTEGRATION);
2860 fun->always_inline_functions_inlined = true;
2862 return todo;
2865 /* Do inlining of small functions. Doing so early helps profiling and other
2866 passes to be somewhat more effective and avoids some code duplication in
2867 later real inlining pass for testcases with very many function calls. */
2869 namespace {
2871 const pass_data pass_data_early_inline =
2873 GIMPLE_PASS, /* type */
2874 "einline", /* name */
2875 OPTGROUP_INLINE, /* optinfo_flags */
2876 TV_EARLY_INLINING, /* tv_id */
2877 PROP_ssa, /* properties_required */
2878 0, /* properties_provided */
2879 0, /* properties_destroyed */
2880 0, /* todo_flags_start */
2881 0, /* todo_flags_finish */
2884 class pass_early_inline : public gimple_opt_pass
2886 public:
2887 pass_early_inline (gcc::context *ctxt)
2888 : gimple_opt_pass (pass_data_early_inline, ctxt)
2891 /* opt_pass methods: */
2892 virtual unsigned int execute (function *);
2894 }; // class pass_early_inline
2896 unsigned int
2897 pass_early_inline::execute (function *fun)
2899 return early_inliner (fun);
2902 } // anon namespace
2904 gimple_opt_pass *
2905 make_pass_early_inline (gcc::context *ctxt)
2907 return new pass_early_inline (ctxt);
2910 namespace {
2912 const pass_data pass_data_ipa_inline =
2914 IPA_PASS, /* type */
2915 "inline", /* name */
2916 OPTGROUP_INLINE, /* optinfo_flags */
2917 TV_IPA_INLINING, /* tv_id */
2918 0, /* properties_required */
2919 0, /* properties_provided */
2920 0, /* properties_destroyed */
2921 0, /* todo_flags_start */
2922 ( TODO_dump_symtab ), /* todo_flags_finish */
2925 class pass_ipa_inline : public ipa_opt_pass_d
2927 public:
2928 pass_ipa_inline (gcc::context *ctxt)
2929 : ipa_opt_pass_d (pass_data_ipa_inline, ctxt,
2930 NULL, /* generate_summary */
2931 NULL, /* write_summary */
2932 NULL, /* read_summary */
2933 NULL, /* write_optimization_summary */
2934 NULL, /* read_optimization_summary */
2935 NULL, /* stmt_fixup */
2936 0, /* function_transform_todo_flags_start */
2937 inline_transform, /* function_transform */
2938 NULL) /* variable_transform */
2941 /* opt_pass methods: */
2942 virtual unsigned int execute (function *) { return ipa_inline (); }
2944 }; // class pass_ipa_inline
2946 } // anon namespace
2948 ipa_opt_pass_d *
2949 make_pass_ipa_inline (gcc::context *ctxt)
2951 return new pass_ipa_inline (ctxt);