2138 lines
67 KiB
C
2138 lines
67 KiB
C
/* Inlining decision heuristics.
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Copyright (C) 2003-2013 Free Software Foundation, Inc.
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Contributed by Jan Hubicka
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This file is part of GCC.
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GCC is free software; you can redistribute it and/or modify it under
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the terms of the GNU General Public License as published by the Free
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Software Foundation; either version 3, or (at your option) any later
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version.
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GCC is distributed in the hope that it will be useful, but WITHOUT ANY
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WARRANTY; without even the implied warranty of MERCHANTABILITY or
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FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
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for more details.
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You should have received a copy of the GNU General Public License
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along with GCC; see the file COPYING3. If not see
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<http://www.gnu.org/licenses/>. */
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/* Inlining decision heuristics
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The implementation of inliner is organized as follows:
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inlining heuristics limits
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can_inline_edge_p allow to check that particular inlining is allowed
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by the limits specified by user (allowed function growth, growth and so
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on).
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Functions are inlined when it is obvious the result is profitable (such
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as functions called once or when inlining reduce code size).
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In addition to that we perform inlining of small functions and recursive
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inlining.
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inlining heuristics
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The inliner itself is split into two passes:
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pass_early_inlining
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Simple local inlining pass inlining callees into current function.
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This pass makes no use of whole unit analysis and thus it can do only
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very simple decisions based on local properties.
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The strength of the pass is that it is run in topological order
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(reverse postorder) on the callgraph. Functions are converted into SSA
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form just before this pass and optimized subsequently. As a result, the
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callees of the function seen by the early inliner was already optimized
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and results of early inlining adds a lot of optimization opportunities
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for the local optimization.
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The pass handle the obvious inlining decisions within the compilation
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unit - inlining auto inline functions, inlining for size and
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flattening.
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main strength of the pass is the ability to eliminate abstraction
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penalty in C++ code (via combination of inlining and early
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optimization) and thus improve quality of analysis done by real IPA
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optimizers.
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Because of lack of whole unit knowledge, the pass can not really make
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good code size/performance tradeoffs. It however does very simple
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speculative inlining allowing code size to grow by
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EARLY_INLINING_INSNS when callee is leaf function. In this case the
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optimizations performed later are very likely to eliminate the cost.
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pass_ipa_inline
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This is the real inliner able to handle inlining with whole program
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knowledge. It performs following steps:
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1) inlining of small functions. This is implemented by greedy
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algorithm ordering all inlinable cgraph edges by their badness and
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inlining them in this order as long as inline limits allows doing so.
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This heuristics is not very good on inlining recursive calls. Recursive
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calls can be inlined with results similar to loop unrolling. To do so,
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special purpose recursive inliner is executed on function when
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recursive edge is met as viable candidate.
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2) Unreachable functions are removed from callgraph. Inlining leads
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to devirtualization and other modification of callgraph so functions
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may become unreachable during the process. Also functions declared as
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extern inline or virtual functions are removed, since after inlining
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we no longer need the offline bodies.
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3) Functions called once and not exported from the unit are inlined.
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This should almost always lead to reduction of code size by eliminating
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the need for offline copy of the function. */
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#include "config.h"
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#include "system.h"
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#include "coretypes.h"
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#include "tm.h"
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#include "tree.h"
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#include "tree-inline.h"
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#include "langhooks.h"
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#include "flags.h"
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#include "cgraph.h"
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#include "diagnostic.h"
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#include "gimple-pretty-print.h"
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#include "params.h"
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#include "fibheap.h"
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#include "intl.h"
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#include "tree-pass.h"
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#include "coverage.h"
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#include "ggc.h"
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#include "rtl.h"
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#include "tree-flow.h"
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#include "ipa-prop.h"
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#include "except.h"
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#include "target.h"
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#include "ipa-inline.h"
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#include "ipa-utils.h"
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/* Statistics we collect about inlining algorithm. */
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static int overall_size;
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static gcov_type max_count;
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/* Return false when inlining edge E would lead to violating
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limits on function unit growth or stack usage growth.
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The relative function body growth limit is present generally
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to avoid problems with non-linear behavior of the compiler.
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To allow inlining huge functions into tiny wrapper, the limit
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is always based on the bigger of the two functions considered.
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For stack growth limits we always base the growth in stack usage
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of the callers. We want to prevent applications from segfaulting
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on stack overflow when functions with huge stack frames gets
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inlined. */
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static bool
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caller_growth_limits (struct cgraph_edge *e)
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{
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struct cgraph_node *to = e->caller;
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struct cgraph_node *what = cgraph_function_or_thunk_node (e->callee, NULL);
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int newsize;
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int limit = 0;
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HOST_WIDE_INT stack_size_limit = 0, inlined_stack;
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struct inline_summary *info, *what_info, *outer_info = inline_summary (to);
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/* Look for function e->caller is inlined to. While doing
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so work out the largest function body on the way. As
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described above, we want to base our function growth
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limits based on that. Not on the self size of the
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outer function, not on the self size of inline code
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we immediately inline to. This is the most relaxed
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interpretation of the rule "do not grow large functions
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too much in order to prevent compiler from exploding". */
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while (true)
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{
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info = inline_summary (to);
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if (limit < info->self_size)
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limit = info->self_size;
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if (stack_size_limit < info->estimated_self_stack_size)
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stack_size_limit = info->estimated_self_stack_size;
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if (to->global.inlined_to)
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to = to->callers->caller;
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else
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break;
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}
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what_info = inline_summary (what);
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if (limit < what_info->self_size)
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limit = what_info->self_size;
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limit += limit * PARAM_VALUE (PARAM_LARGE_FUNCTION_GROWTH) / 100;
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/* Check the size after inlining against the function limits. But allow
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the function to shrink if it went over the limits by forced inlining. */
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newsize = estimate_size_after_inlining (to, e);
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if (newsize >= info->size
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&& newsize > PARAM_VALUE (PARAM_LARGE_FUNCTION_INSNS)
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&& newsize > limit)
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{
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e->inline_failed = CIF_LARGE_FUNCTION_GROWTH_LIMIT;
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return false;
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}
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if (!what_info->estimated_stack_size)
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return true;
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/* FIXME: Stack size limit often prevents inlining in Fortran programs
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due to large i/o datastructures used by the Fortran front-end.
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We ought to ignore this limit when we know that the edge is executed
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on every invocation of the caller (i.e. its call statement dominates
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exit block). We do not track this information, yet. */
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stack_size_limit += ((gcov_type)stack_size_limit
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* PARAM_VALUE (PARAM_STACK_FRAME_GROWTH) / 100);
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inlined_stack = (outer_info->stack_frame_offset
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+ outer_info->estimated_self_stack_size
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+ what_info->estimated_stack_size);
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/* Check new stack consumption with stack consumption at the place
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stack is used. */
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if (inlined_stack > stack_size_limit
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/* If function already has large stack usage from sibling
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inline call, we can inline, too.
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This bit overoptimistically assume that we are good at stack
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packing. */
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&& inlined_stack > info->estimated_stack_size
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&& inlined_stack > PARAM_VALUE (PARAM_LARGE_STACK_FRAME))
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{
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e->inline_failed = CIF_LARGE_STACK_FRAME_GROWTH_LIMIT;
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return false;
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}
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return true;
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}
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/* Dump info about why inlining has failed. */
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static void
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report_inline_failed_reason (struct cgraph_edge *e)
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{
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if (dump_file)
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{
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fprintf (dump_file, " not inlinable: %s/%i -> %s/%i, %s\n",
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xstrdup (cgraph_node_name (e->caller)), e->caller->uid,
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xstrdup (cgraph_node_name (e->callee)), e->callee->uid,
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cgraph_inline_failed_string (e->inline_failed));
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}
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}
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/* Decide if we can inline the edge and possibly update
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inline_failed reason.
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We check whether inlining is possible at all and whether
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caller growth limits allow doing so.
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if REPORT is true, output reason to the dump file. */
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static bool
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can_inline_edge_p (struct cgraph_edge *e, bool report)
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{
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bool inlinable = true;
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enum availability avail;
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struct cgraph_node *callee
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= cgraph_function_or_thunk_node (e->callee, &avail);
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tree caller_tree = DECL_FUNCTION_SPECIFIC_OPTIMIZATION (e->caller->symbol.decl);
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tree callee_tree
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= callee ? DECL_FUNCTION_SPECIFIC_OPTIMIZATION (callee->symbol.decl) : NULL;
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struct function *caller_cfun = DECL_STRUCT_FUNCTION (e->caller->symbol.decl);
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struct function *callee_cfun
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= callee ? DECL_STRUCT_FUNCTION (callee->symbol.decl) : NULL;
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if (!caller_cfun && e->caller->clone_of)
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caller_cfun = DECL_STRUCT_FUNCTION (e->caller->clone_of->symbol.decl);
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if (!callee_cfun && callee && callee->clone_of)
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callee_cfun = DECL_STRUCT_FUNCTION (callee->clone_of->symbol.decl);
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gcc_assert (e->inline_failed);
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if (!callee || !callee->analyzed)
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{
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e->inline_failed = CIF_BODY_NOT_AVAILABLE;
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inlinable = false;
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}
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else if (!inline_summary (callee)->inlinable)
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{
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e->inline_failed = CIF_FUNCTION_NOT_INLINABLE;
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inlinable = false;
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}
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else if (avail <= AVAIL_OVERWRITABLE)
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{
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e->inline_failed = CIF_OVERWRITABLE;
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return false;
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}
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else if (e->call_stmt_cannot_inline_p)
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{
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e->inline_failed = CIF_MISMATCHED_ARGUMENTS;
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inlinable = false;
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}
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/* Don't inline if the functions have different EH personalities. */
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else if (DECL_FUNCTION_PERSONALITY (e->caller->symbol.decl)
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&& DECL_FUNCTION_PERSONALITY (callee->symbol.decl)
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&& (DECL_FUNCTION_PERSONALITY (e->caller->symbol.decl)
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!= DECL_FUNCTION_PERSONALITY (callee->symbol.decl)))
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{
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e->inline_failed = CIF_EH_PERSONALITY;
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inlinable = false;
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}
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/* TM pure functions should not be inlined into non-TM_pure
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functions. */
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else if (is_tm_pure (callee->symbol.decl)
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&& !is_tm_pure (e->caller->symbol.decl))
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{
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e->inline_failed = CIF_UNSPECIFIED;
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inlinable = false;
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}
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/* Don't inline if the callee can throw non-call exceptions but the
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caller cannot.
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FIXME: this is obviously wrong for LTO where STRUCT_FUNCTION is missing.
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Move the flag into cgraph node or mirror it in the inline summary. */
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else if (callee_cfun && callee_cfun->can_throw_non_call_exceptions
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&& !(caller_cfun && caller_cfun->can_throw_non_call_exceptions))
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{
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e->inline_failed = CIF_NON_CALL_EXCEPTIONS;
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inlinable = false;
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}
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/* Check compatibility of target optimization options. */
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else if (!targetm.target_option.can_inline_p (e->caller->symbol.decl,
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callee->symbol.decl))
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{
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e->inline_failed = CIF_TARGET_OPTION_MISMATCH;
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inlinable = false;
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}
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/* Check if caller growth allows the inlining. */
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else if (!DECL_DISREGARD_INLINE_LIMITS (callee->symbol.decl)
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&& !lookup_attribute ("flatten",
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DECL_ATTRIBUTES
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(e->caller->global.inlined_to
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? e->caller->global.inlined_to->symbol.decl
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: e->caller->symbol.decl))
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&& !caller_growth_limits (e))
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inlinable = false;
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/* Don't inline a function with a higher optimization level than the
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caller. FIXME: this is really just tip of iceberg of handling
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optimization attribute. */
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else if (caller_tree != callee_tree)
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{
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struct cl_optimization *caller_opt
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= TREE_OPTIMIZATION ((caller_tree)
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? caller_tree
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: optimization_default_node);
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struct cl_optimization *callee_opt
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= TREE_OPTIMIZATION ((callee_tree)
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? callee_tree
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: optimization_default_node);
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if (((caller_opt->x_optimize > callee_opt->x_optimize)
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|| (caller_opt->x_optimize_size != callee_opt->x_optimize_size))
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/* gcc.dg/pr43564.c. Look at forced inline even in -O0. */
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&& !DECL_DISREGARD_INLINE_LIMITS (e->callee->symbol.decl))
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{
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e->inline_failed = CIF_OPTIMIZATION_MISMATCH;
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inlinable = false;
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}
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}
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if (!inlinable && report)
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report_inline_failed_reason (e);
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return inlinable;
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}
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/* Return true if the edge E is inlinable during early inlining. */
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static bool
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can_early_inline_edge_p (struct cgraph_edge *e)
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{
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struct cgraph_node *callee = cgraph_function_or_thunk_node (e->callee,
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NULL);
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/* Early inliner might get called at WPA stage when IPA pass adds new
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function. In this case we can not really do any of early inlining
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because function bodies are missing. */
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if (!gimple_has_body_p (callee->symbol.decl))
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{
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e->inline_failed = CIF_BODY_NOT_AVAILABLE;
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return false;
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}
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/* In early inliner some of callees may not be in SSA form yet
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(i.e. the callgraph is cyclic and we did not process
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the callee by early inliner, yet). We don't have CIF code for this
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case; later we will re-do the decision in the real inliner. */
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if (!gimple_in_ssa_p (DECL_STRUCT_FUNCTION (e->caller->symbol.decl))
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|| !gimple_in_ssa_p (DECL_STRUCT_FUNCTION (callee->symbol.decl)))
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{
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if (dump_file)
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fprintf (dump_file, " edge not inlinable: not in SSA form\n");
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return false;
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}
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if (!can_inline_edge_p (e, true))
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return false;
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return true;
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}
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/* Return number of calls in N. Ignore cheap builtins. */
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static int
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num_calls (struct cgraph_node *n)
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{
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struct cgraph_edge *e;
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int num = 0;
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for (e = n->callees; e; e = e->next_callee)
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if (!is_inexpensive_builtin (e->callee->symbol.decl))
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num++;
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return num;
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}
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/* Return true if we are interested in inlining small function. */
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static bool
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want_early_inline_function_p (struct cgraph_edge *e)
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{
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bool want_inline = true;
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struct cgraph_node *callee = cgraph_function_or_thunk_node (e->callee, NULL);
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if (DECL_DISREGARD_INLINE_LIMITS (callee->symbol.decl))
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;
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else if (!DECL_DECLARED_INLINE_P (callee->symbol.decl)
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&& !flag_inline_small_functions)
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{
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e->inline_failed = CIF_FUNCTION_NOT_INLINE_CANDIDATE;
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report_inline_failed_reason (e);
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want_inline = false;
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}
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else
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{
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int growth = estimate_edge_growth (e);
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int n;
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if (growth <= 0)
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;
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else if (!cgraph_maybe_hot_edge_p (e)
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&& growth > 0)
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{
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if (dump_file)
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fprintf (dump_file, " will not early inline: %s/%i->%s/%i, "
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"call is cold and code would grow by %i\n",
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xstrdup (cgraph_node_name (e->caller)), e->caller->uid,
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xstrdup (cgraph_node_name (callee)), callee->uid,
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growth);
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want_inline = false;
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}
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else if (growth > PARAM_VALUE (PARAM_EARLY_INLINING_INSNS))
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{
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if (dump_file)
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fprintf (dump_file, " will not early inline: %s/%i->%s/%i, "
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"growth %i exceeds --param early-inlining-insns\n",
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xstrdup (cgraph_node_name (e->caller)), e->caller->uid,
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xstrdup (cgraph_node_name (callee)), callee->uid,
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growth);
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want_inline = false;
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}
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else if ((n = num_calls (callee)) != 0
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&& growth * (n + 1) > PARAM_VALUE (PARAM_EARLY_INLINING_INSNS))
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{
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if (dump_file)
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fprintf (dump_file, " will not early inline: %s/%i->%s/%i, "
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"growth %i exceeds --param early-inlining-insns "
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"divided by number of calls\n",
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xstrdup (cgraph_node_name (e->caller)), e->caller->uid,
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xstrdup (cgraph_node_name (callee)), callee->uid,
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growth);
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want_inline = false;
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}
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}
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return want_inline;
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}
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/* Compute time of the edge->caller + edge->callee execution when inlining
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does not happen. */
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inline gcov_type
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compute_uninlined_call_time (struct inline_summary *callee_info,
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struct cgraph_edge *edge)
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{
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gcov_type uninlined_call_time =
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RDIV ((gcov_type)callee_info->time * MAX (edge->frequency, 1),
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CGRAPH_FREQ_BASE);
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gcov_type caller_time = inline_summary (edge->caller->global.inlined_to
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? edge->caller->global.inlined_to
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: edge->caller)->time;
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return uninlined_call_time + caller_time;
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}
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/* Same as compute_uinlined_call_time but compute time when inlining
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does happen. */
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inline gcov_type
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compute_inlined_call_time (struct cgraph_edge *edge,
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int edge_time)
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{
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gcov_type caller_time = inline_summary (edge->caller->global.inlined_to
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? edge->caller->global.inlined_to
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: edge->caller)->time;
|
|
gcov_type time = (caller_time
|
|
+ RDIV (((gcov_type) edge_time
|
|
- inline_edge_summary (edge)->call_stmt_time)
|
|
* MAX (edge->frequency, 1), CGRAPH_FREQ_BASE));
|
|
/* Possible one roundoff error, but watch for overflows. */
|
|
gcc_checking_assert (time >= INT_MIN / 2);
|
|
if (time < 0)
|
|
time = 0;
|
|
return time;
|
|
}
|
|
|
|
/* Return true if the speedup for inlining E is bigger than
|
|
PARAM_MAX_INLINE_MIN_SPEEDUP. */
|
|
|
|
static bool
|
|
big_speedup_p (struct cgraph_edge *e)
|
|
{
|
|
gcov_type time = compute_uninlined_call_time (inline_summary (e->callee),
|
|
e);
|
|
gcov_type inlined_time = compute_inlined_call_time (e,
|
|
estimate_edge_time (e));
|
|
if (time - inlined_time
|
|
> RDIV (time * PARAM_VALUE (PARAM_INLINE_MIN_SPEEDUP), 100))
|
|
return true;
|
|
return false;
|
|
}
|
|
|
|
/* Return true if we are interested in inlining small function.
|
|
When REPORT is true, report reason to dump file. */
|
|
|
|
static bool
|
|
want_inline_small_function_p (struct cgraph_edge *e, bool report)
|
|
{
|
|
bool want_inline = true;
|
|
struct cgraph_node *callee = cgraph_function_or_thunk_node (e->callee, NULL);
|
|
|
|
if (DECL_DISREGARD_INLINE_LIMITS (callee->symbol.decl))
|
|
;
|
|
else if (!DECL_DECLARED_INLINE_P (callee->symbol.decl)
|
|
&& !flag_inline_small_functions)
|
|
{
|
|
e->inline_failed = CIF_FUNCTION_NOT_INLINE_CANDIDATE;
|
|
want_inline = false;
|
|
}
|
|
else
|
|
{
|
|
int growth = estimate_edge_growth (e);
|
|
inline_hints hints = estimate_edge_hints (e);
|
|
bool big_speedup = big_speedup_p (e);
|
|
|
|
if (growth <= 0)
|
|
;
|
|
/* Apply MAX_INLINE_INSNS_SINGLE limit. Do not do so when
|
|
hints suggests that inlining given function is very profitable. */
|
|
else if (DECL_DECLARED_INLINE_P (callee->symbol.decl)
|
|
&& growth >= MAX_INLINE_INSNS_SINGLE
|
|
&& !big_speedup
|
|
&& !(hints & (INLINE_HINT_indirect_call
|
|
| INLINE_HINT_loop_iterations
|
|
| INLINE_HINT_array_index
|
|
| INLINE_HINT_loop_stride)))
|
|
{
|
|
e->inline_failed = CIF_MAX_INLINE_INSNS_SINGLE_LIMIT;
|
|
want_inline = false;
|
|
}
|
|
/* Before giving up based on fact that caller size will grow, allow
|
|
functions that are called few times and eliminating the offline
|
|
copy will lead to overall code size reduction.
|
|
Not all of these will be handled by subsequent inlining of functions
|
|
called once: in particular weak functions are not handled or funcitons
|
|
that inline to multiple calls but a lot of bodies is optimized out.
|
|
Finally we want to inline earlier to allow inlining of callbacks.
|
|
|
|
This is slightly wrong on aggressive side: it is entirely possible
|
|
that function is called many times with a context where inlining
|
|
reduces code size and few times with a context where inlining increase
|
|
code size. Resoluting growth estimate will be negative even if it
|
|
would make more sense to keep offline copy and do not inline into the
|
|
call sites that makes the code size grow.
|
|
|
|
When badness orders the calls in a way that code reducing calls come
|
|
first, this situation is not a problem at all: after inlining all
|
|
"good" calls, we will realize that keeping the function around is
|
|
better. */
|
|
else if (growth <= MAX_INLINE_INSNS_SINGLE
|
|
/* Unlike for functions called once, we play unsafe with
|
|
COMDATs. We can allow that since we know functions
|
|
in consideration are small (and thus risk is small) and
|
|
moreover grow estimates already accounts that COMDAT
|
|
functions may or may not disappear when eliminated from
|
|
current unit. With good probability making aggressive
|
|
choice in all units is going to make overall program
|
|
smaller.
|
|
|
|
Consequently we ask cgraph_can_remove_if_no_direct_calls_p
|
|
instead of
|
|
cgraph_will_be_removed_from_program_if_no_direct_calls */
|
|
&& !DECL_EXTERNAL (callee->symbol.decl)
|
|
&& cgraph_can_remove_if_no_direct_calls_p (callee)
|
|
&& estimate_growth (callee) <= 0)
|
|
;
|
|
else if (!DECL_DECLARED_INLINE_P (callee->symbol.decl)
|
|
&& !flag_inline_functions)
|
|
{
|
|
e->inline_failed = CIF_NOT_DECLARED_INLINED;
|
|
want_inline = false;
|
|
}
|
|
/* Apply MAX_INLINE_INSNS_AUTO limit for functions not declared inline
|
|
Upgrade it to MAX_INLINE_INSNS_SINGLE when hints suggests that
|
|
inlining given function is very profitable. */
|
|
else if (!DECL_DECLARED_INLINE_P (callee->symbol.decl)
|
|
&& !big_speedup
|
|
&& growth >= ((hints & (INLINE_HINT_indirect_call
|
|
| INLINE_HINT_loop_iterations
|
|
| INLINE_HINT_array_index
|
|
| INLINE_HINT_loop_stride))
|
|
? MAX (MAX_INLINE_INSNS_AUTO,
|
|
MAX_INLINE_INSNS_SINGLE)
|
|
: MAX_INLINE_INSNS_AUTO))
|
|
{
|
|
e->inline_failed = CIF_MAX_INLINE_INSNS_AUTO_LIMIT;
|
|
want_inline = false;
|
|
}
|
|
/* If call is cold, do not inline when function body would grow. */
|
|
else if (!cgraph_maybe_hot_edge_p (e))
|
|
{
|
|
e->inline_failed = CIF_UNLIKELY_CALL;
|
|
want_inline = false;
|
|
}
|
|
}
|
|
if (!want_inline && report)
|
|
report_inline_failed_reason (e);
|
|
return want_inline;
|
|
}
|
|
|
|
/* EDGE is self recursive edge.
|
|
We hand two cases - when function A is inlining into itself
|
|
or when function A is being inlined into another inliner copy of function
|
|
A within function B.
|
|
|
|
In first case OUTER_NODE points to the toplevel copy of A, while
|
|
in the second case OUTER_NODE points to the outermost copy of A in B.
|
|
|
|
In both cases we want to be extra selective since
|
|
inlining the call will just introduce new recursive calls to appear. */
|
|
|
|
static bool
|
|
want_inline_self_recursive_call_p (struct cgraph_edge *edge,
|
|
struct cgraph_node *outer_node,
|
|
bool peeling,
|
|
int depth)
|
|
{
|
|
char const *reason = NULL;
|
|
bool want_inline = true;
|
|
int caller_freq = CGRAPH_FREQ_BASE;
|
|
int max_depth = PARAM_VALUE (PARAM_MAX_INLINE_RECURSIVE_DEPTH_AUTO);
|
|
|
|
if (DECL_DECLARED_INLINE_P (edge->caller->symbol.decl))
|
|
max_depth = PARAM_VALUE (PARAM_MAX_INLINE_RECURSIVE_DEPTH);
|
|
|
|
if (!cgraph_maybe_hot_edge_p (edge))
|
|
{
|
|
reason = "recursive call is cold";
|
|
want_inline = false;
|
|
}
|
|
else if (max_count && !outer_node->count)
|
|
{
|
|
reason = "not executed in profile";
|
|
want_inline = false;
|
|
}
|
|
else if (depth > max_depth)
|
|
{
|
|
reason = "--param max-inline-recursive-depth exceeded.";
|
|
want_inline = false;
|
|
}
|
|
|
|
if (outer_node->global.inlined_to)
|
|
caller_freq = outer_node->callers->frequency;
|
|
|
|
if (!want_inline)
|
|
;
|
|
/* Inlining of self recursive function into copy of itself within other function
|
|
is transformation similar to loop peeling.
|
|
|
|
Peeling is profitable if we can inline enough copies to make probability
|
|
of actual call to the self recursive function very small. Be sure that
|
|
the probability of recursion is small.
|
|
|
|
We ensure that the frequency of recursing is at most 1 - (1/max_depth).
|
|
This way the expected number of recision is at most max_depth. */
|
|
else if (peeling)
|
|
{
|
|
int max_prob = CGRAPH_FREQ_BASE - ((CGRAPH_FREQ_BASE + max_depth - 1)
|
|
/ max_depth);
|
|
int i;
|
|
for (i = 1; i < depth; i++)
|
|
max_prob = max_prob * max_prob / CGRAPH_FREQ_BASE;
|
|
if (max_count
|
|
&& (edge->count * CGRAPH_FREQ_BASE / outer_node->count
|
|
>= max_prob))
|
|
{
|
|
reason = "profile of recursive call is too large";
|
|
want_inline = false;
|
|
}
|
|
if (!max_count
|
|
&& (edge->frequency * CGRAPH_FREQ_BASE / caller_freq
|
|
>= max_prob))
|
|
{
|
|
reason = "frequency of recursive call is too large";
|
|
want_inline = false;
|
|
}
|
|
}
|
|
/* Recursive inlining, i.e. equivalent of unrolling, is profitable if recursion
|
|
depth is large. We reduce function call overhead and increase chances that
|
|
things fit in hardware return predictor.
|
|
|
|
Recursive inlining might however increase cost of stack frame setup
|
|
actually slowing down functions whose recursion tree is wide rather than
|
|
deep.
|
|
|
|
Deciding reliably on when to do recursive inlining without profile feedback
|
|
is tricky. For now we disable recursive inlining when probability of self
|
|
recursion is low.
|
|
|
|
Recursive inlining of self recursive call within loop also results in large loop
|
|
depths that generally optimize badly. We may want to throttle down inlining
|
|
in those cases. In particular this seems to happen in one of libstdc++ rb tree
|
|
methods. */
|
|
else
|
|
{
|
|
if (max_count
|
|
&& (edge->count * 100 / outer_node->count
|
|
<= PARAM_VALUE (PARAM_MIN_INLINE_RECURSIVE_PROBABILITY)))
|
|
{
|
|
reason = "profile of recursive call is too small";
|
|
want_inline = false;
|
|
}
|
|
else if (!max_count
|
|
&& (edge->frequency * 100 / caller_freq
|
|
<= PARAM_VALUE (PARAM_MIN_INLINE_RECURSIVE_PROBABILITY)))
|
|
{
|
|
reason = "frequency of recursive call is too small";
|
|
want_inline = false;
|
|
}
|
|
}
|
|
if (!want_inline && dump_file)
|
|
fprintf (dump_file, " not inlining recursively: %s\n", reason);
|
|
return want_inline;
|
|
}
|
|
|
|
/* Return true when NODE has caller other than EDGE.
|
|
Worker for cgraph_for_node_and_aliases. */
|
|
|
|
static bool
|
|
check_caller_edge (struct cgraph_node *node, void *edge)
|
|
{
|
|
return (node->callers
|
|
&& node->callers != edge);
|
|
}
|
|
|
|
|
|
/* Decide if inlining NODE would reduce unit size by eliminating
|
|
the offline copy of function.
|
|
When COLD is true the cold calls are considered, too. */
|
|
|
|
static bool
|
|
want_inline_function_to_all_callers_p (struct cgraph_node *node, bool cold)
|
|
{
|
|
struct cgraph_node *function = cgraph_function_or_thunk_node (node, NULL);
|
|
struct cgraph_edge *e;
|
|
bool has_hot_call = false;
|
|
|
|
/* Does it have callers? */
|
|
if (!node->callers)
|
|
return false;
|
|
/* Already inlined? */
|
|
if (function->global.inlined_to)
|
|
return false;
|
|
if (cgraph_function_or_thunk_node (node, NULL) != node)
|
|
return false;
|
|
/* Inlining into all callers would increase size? */
|
|
if (estimate_growth (node) > 0)
|
|
return false;
|
|
/* Maybe other aliases has more direct calls. */
|
|
if (cgraph_for_node_and_aliases (node, check_caller_edge, node->callers, true))
|
|
return false;
|
|
/* All inlines must be possible. */
|
|
for (e = node->callers; e; e = e->next_caller)
|
|
{
|
|
if (!can_inline_edge_p (e, true))
|
|
return false;
|
|
if (!has_hot_call && cgraph_maybe_hot_edge_p (e))
|
|
has_hot_call = 1;
|
|
}
|
|
|
|
if (!cold && !has_hot_call)
|
|
return false;
|
|
return true;
|
|
}
|
|
|
|
#define RELATIVE_TIME_BENEFIT_RANGE (INT_MAX / 64)
|
|
|
|
/* Return relative time improvement for inlining EDGE in range
|
|
1...RELATIVE_TIME_BENEFIT_RANGE */
|
|
|
|
static inline int
|
|
relative_time_benefit (struct inline_summary *callee_info,
|
|
struct cgraph_edge *edge,
|
|
int edge_time)
|
|
{
|
|
gcov_type relbenefit;
|
|
gcov_type uninlined_call_time = compute_uninlined_call_time (callee_info, edge);
|
|
gcov_type inlined_call_time = compute_inlined_call_time (edge, edge_time);
|
|
|
|
/* Inlining into extern inline function is not a win. */
|
|
if (DECL_EXTERNAL (edge->caller->global.inlined_to
|
|
? edge->caller->global.inlined_to->symbol.decl
|
|
: edge->caller->symbol.decl))
|
|
return 1;
|
|
|
|
/* Watch overflows. */
|
|
gcc_checking_assert (uninlined_call_time >= 0);
|
|
gcc_checking_assert (inlined_call_time >= 0);
|
|
gcc_checking_assert (uninlined_call_time >= inlined_call_time);
|
|
|
|
/* Compute relative time benefit, i.e. how much the call becomes faster.
|
|
??? perhaps computing how much the caller+calle together become faster
|
|
would lead to more realistic results. */
|
|
if (!uninlined_call_time)
|
|
uninlined_call_time = 1;
|
|
relbenefit =
|
|
RDIV (((gcov_type)uninlined_call_time - inlined_call_time) * RELATIVE_TIME_BENEFIT_RANGE,
|
|
uninlined_call_time);
|
|
relbenefit = MIN (relbenefit, RELATIVE_TIME_BENEFIT_RANGE);
|
|
gcc_checking_assert (relbenefit >= 0);
|
|
relbenefit = MAX (relbenefit, 1);
|
|
return relbenefit;
|
|
}
|
|
|
|
|
|
/* A cost model driving the inlining heuristics in a way so the edges with
|
|
smallest badness are inlined first. After each inlining is performed
|
|
the costs of all caller edges of nodes affected are recomputed so the
|
|
metrics may accurately depend on values such as number of inlinable callers
|
|
of the function or function body size. */
|
|
|
|
static int
|
|
edge_badness (struct cgraph_edge *edge, bool dump)
|
|
{
|
|
gcov_type badness;
|
|
int growth, edge_time;
|
|
struct cgraph_node *callee = cgraph_function_or_thunk_node (edge->callee,
|
|
NULL);
|
|
struct inline_summary *callee_info = inline_summary (callee);
|
|
inline_hints hints;
|
|
|
|
if (DECL_DISREGARD_INLINE_LIMITS (callee->symbol.decl))
|
|
return INT_MIN;
|
|
|
|
growth = estimate_edge_growth (edge);
|
|
edge_time = estimate_edge_time (edge);
|
|
hints = estimate_edge_hints (edge);
|
|
gcc_checking_assert (edge_time >= 0);
|
|
gcc_checking_assert (edge_time <= callee_info->time);
|
|
gcc_checking_assert (growth <= callee_info->size);
|
|
|
|
if (dump)
|
|
{
|
|
fprintf (dump_file, " Badness calculation for %s/%i -> %s/%i\n",
|
|
xstrdup (cgraph_node_name (edge->caller)),
|
|
edge->caller->uid,
|
|
xstrdup (cgraph_node_name (callee)),
|
|
edge->callee->uid);
|
|
fprintf (dump_file, " size growth %i, time %i ",
|
|
growth,
|
|
edge_time);
|
|
dump_inline_hints (dump_file, hints);
|
|
if (big_speedup_p (edge))
|
|
fprintf (dump_file, " big_speedup");
|
|
fprintf (dump_file, "\n");
|
|
}
|
|
|
|
/* Always prefer inlining saving code size. */
|
|
if (growth <= 0)
|
|
{
|
|
badness = INT_MIN / 2 + growth;
|
|
if (dump)
|
|
fprintf (dump_file, " %i: Growth %i <= 0\n", (int) badness,
|
|
growth);
|
|
}
|
|
|
|
/* When profiling is available, compute badness as:
|
|
|
|
relative_edge_count * relative_time_benefit
|
|
goodness = -------------------------------------------
|
|
growth_f_caller
|
|
badness = -goodness
|
|
|
|
The fraction is upside down, because on edge counts and time beneits
|
|
the bounds are known. Edge growth is essentially unlimited. */
|
|
|
|
else if (max_count)
|
|
{
|
|
int relbenefit = relative_time_benefit (callee_info, edge, edge_time);
|
|
badness =
|
|
((int)
|
|
((double) edge->count * INT_MIN / 2 / max_count / RELATIVE_TIME_BENEFIT_RANGE) *
|
|
relbenefit) / growth;
|
|
|
|
/* Be sure that insanity of the profile won't lead to increasing counts
|
|
in the scalling and thus to overflow in the computation above. */
|
|
gcc_assert (max_count >= edge->count);
|
|
if (dump)
|
|
{
|
|
fprintf (dump_file,
|
|
" %i (relative %f): profile info. Relative count %f"
|
|
" * Relative benefit %f\n",
|
|
(int) badness, (double) badness / INT_MIN,
|
|
(double) edge->count / max_count,
|
|
relbenefit * 100.0 / RELATIVE_TIME_BENEFIT_RANGE);
|
|
}
|
|
}
|
|
|
|
/* When function local profile is available. Compute badness as:
|
|
|
|
relative_time_benefit
|
|
goodness = ---------------------------------
|
|
growth_of_caller * overall_growth
|
|
|
|
badness = - goodness
|
|
|
|
compensated by the inline hints.
|
|
*/
|
|
else if (flag_guess_branch_prob)
|
|
{
|
|
badness = (relative_time_benefit (callee_info, edge, edge_time)
|
|
* (INT_MIN / 16 / RELATIVE_TIME_BENEFIT_RANGE));
|
|
badness /= (MIN (65536/2, growth) * MIN (65536/2, MAX (1, callee_info->growth)));
|
|
gcc_checking_assert (badness <=0 && badness >= INT_MIN / 16);
|
|
if ((hints & (INLINE_HINT_indirect_call
|
|
| INLINE_HINT_loop_iterations
|
|
| INLINE_HINT_array_index
|
|
| INLINE_HINT_loop_stride))
|
|
|| callee_info->growth <= 0)
|
|
badness *= 8;
|
|
if (hints & (INLINE_HINT_same_scc))
|
|
badness /= 16;
|
|
else if (hints & (INLINE_HINT_in_scc))
|
|
badness /= 8;
|
|
else if (hints & (INLINE_HINT_cross_module))
|
|
badness /= 2;
|
|
gcc_checking_assert (badness <= 0 && badness >= INT_MIN / 2);
|
|
if ((hints & INLINE_HINT_declared_inline) && badness >= INT_MIN / 32)
|
|
badness *= 16;
|
|
if (dump)
|
|
{
|
|
fprintf (dump_file,
|
|
" %i: guessed profile. frequency %f,"
|
|
" benefit %f%%, time w/o inlining %i, time w inlining %i"
|
|
" overall growth %i (current) %i (original)\n",
|
|
(int) badness, (double)edge->frequency / CGRAPH_FREQ_BASE,
|
|
relative_time_benefit (callee_info, edge, edge_time) * 100.0
|
|
/ RELATIVE_TIME_BENEFIT_RANGE,
|
|
(int)compute_uninlined_call_time (callee_info, edge),
|
|
(int)compute_inlined_call_time (edge, edge_time),
|
|
estimate_growth (callee),
|
|
callee_info->growth);
|
|
}
|
|
}
|
|
/* When function local profile is not available or it does not give
|
|
useful information (ie frequency is zero), base the cost on
|
|
loop nest and overall size growth, so we optimize for overall number
|
|
of functions fully inlined in program. */
|
|
else
|
|
{
|
|
int nest = MIN (inline_edge_summary (edge)->loop_depth, 8);
|
|
badness = growth * 256;
|
|
|
|
/* Decrease badness if call is nested. */
|
|
if (badness > 0)
|
|
badness >>= nest;
|
|
else
|
|
{
|
|
badness <<= nest;
|
|
}
|
|
if (dump)
|
|
fprintf (dump_file, " %i: no profile. nest %i\n", (int) badness,
|
|
nest);
|
|
}
|
|
|
|
/* Ensure that we did not overflow in all the fixed point math above. */
|
|
gcc_assert (badness >= INT_MIN);
|
|
gcc_assert (badness <= INT_MAX - 1);
|
|
/* Make recursive inlining happen always after other inlining is done. */
|
|
if (cgraph_edge_recursive_p (edge))
|
|
return badness + 1;
|
|
else
|
|
return badness;
|
|
}
|
|
|
|
/* Recompute badness of EDGE and update its key in HEAP if needed. */
|
|
static inline void
|
|
update_edge_key (fibheap_t heap, struct cgraph_edge *edge)
|
|
{
|
|
int badness = edge_badness (edge, false);
|
|
if (edge->aux)
|
|
{
|
|
fibnode_t n = (fibnode_t) edge->aux;
|
|
gcc_checking_assert (n->data == edge);
|
|
|
|
/* fibheap_replace_key only decrease the keys.
|
|
When we increase the key we do not update heap
|
|
and instead re-insert the element once it becomes
|
|
a minimum of heap. */
|
|
if (badness < n->key)
|
|
{
|
|
if (dump_file && (dump_flags & TDF_DETAILS))
|
|
{
|
|
fprintf (dump_file,
|
|
" decreasing badness %s/%i -> %s/%i, %i to %i\n",
|
|
xstrdup (cgraph_node_name (edge->caller)),
|
|
edge->caller->uid,
|
|
xstrdup (cgraph_node_name (edge->callee)),
|
|
edge->callee->uid,
|
|
(int)n->key,
|
|
badness);
|
|
}
|
|
fibheap_replace_key (heap, n, badness);
|
|
gcc_checking_assert (n->key == badness);
|
|
}
|
|
}
|
|
else
|
|
{
|
|
if (dump_file && (dump_flags & TDF_DETAILS))
|
|
{
|
|
fprintf (dump_file,
|
|
" enqueuing call %s/%i -> %s/%i, badness %i\n",
|
|
xstrdup (cgraph_node_name (edge->caller)),
|
|
edge->caller->uid,
|
|
xstrdup (cgraph_node_name (edge->callee)),
|
|
edge->callee->uid,
|
|
badness);
|
|
}
|
|
edge->aux = fibheap_insert (heap, badness, edge);
|
|
}
|
|
}
|
|
|
|
|
|
/* NODE was inlined.
|
|
All caller edges needs to be resetted because
|
|
size estimates change. Similarly callees needs reset
|
|
because better context may be known. */
|
|
|
|
static void
|
|
reset_edge_caches (struct cgraph_node *node)
|
|
{
|
|
struct cgraph_edge *edge;
|
|
struct cgraph_edge *e = node->callees;
|
|
struct cgraph_node *where = node;
|
|
int i;
|
|
struct ipa_ref *ref;
|
|
|
|
if (where->global.inlined_to)
|
|
where = where->global.inlined_to;
|
|
|
|
/* WHERE body size has changed, the cached growth is invalid. */
|
|
reset_node_growth_cache (where);
|
|
|
|
for (edge = where->callers; edge; edge = edge->next_caller)
|
|
if (edge->inline_failed)
|
|
reset_edge_growth_cache (edge);
|
|
for (i = 0; ipa_ref_list_referring_iterate (&where->symbol.ref_list,
|
|
i, ref); i++)
|
|
if (ref->use == IPA_REF_ALIAS)
|
|
reset_edge_caches (ipa_ref_referring_node (ref));
|
|
|
|
if (!e)
|
|
return;
|
|
|
|
while (true)
|
|
if (!e->inline_failed && e->callee->callees)
|
|
e = e->callee->callees;
|
|
else
|
|
{
|
|
if (e->inline_failed)
|
|
reset_edge_growth_cache (e);
|
|
if (e->next_callee)
|
|
e = e->next_callee;
|
|
else
|
|
{
|
|
do
|
|
{
|
|
if (e->caller == node)
|
|
return;
|
|
e = e->caller->callers;
|
|
}
|
|
while (!e->next_callee);
|
|
e = e->next_callee;
|
|
}
|
|
}
|
|
}
|
|
|
|
/* Recompute HEAP nodes for each of caller of NODE.
|
|
UPDATED_NODES track nodes we already visited, to avoid redundant work.
|
|
When CHECK_INLINABLITY_FOR is set, re-check for specified edge that
|
|
it is inlinable. Otherwise check all edges. */
|
|
|
|
static void
|
|
update_caller_keys (fibheap_t heap, struct cgraph_node *node,
|
|
bitmap updated_nodes,
|
|
struct cgraph_edge *check_inlinablity_for)
|
|
{
|
|
struct cgraph_edge *edge;
|
|
int i;
|
|
struct ipa_ref *ref;
|
|
|
|
if ((!node->alias && !inline_summary (node)->inlinable)
|
|
|| cgraph_function_body_availability (node) <= AVAIL_OVERWRITABLE
|
|
|| node->global.inlined_to)
|
|
return;
|
|
if (!bitmap_set_bit (updated_nodes, node->uid))
|
|
return;
|
|
|
|
for (i = 0; ipa_ref_list_referring_iterate (&node->symbol.ref_list,
|
|
i, ref); i++)
|
|
if (ref->use == IPA_REF_ALIAS)
|
|
{
|
|
struct cgraph_node *alias = ipa_ref_referring_node (ref);
|
|
update_caller_keys (heap, alias, updated_nodes, check_inlinablity_for);
|
|
}
|
|
|
|
for (edge = node->callers; edge; edge = edge->next_caller)
|
|
if (edge->inline_failed)
|
|
{
|
|
if (!check_inlinablity_for
|
|
|| check_inlinablity_for == edge)
|
|
{
|
|
if (can_inline_edge_p (edge, false)
|
|
&& want_inline_small_function_p (edge, false))
|
|
update_edge_key (heap, edge);
|
|
else if (edge->aux)
|
|
{
|
|
report_inline_failed_reason (edge);
|
|
fibheap_delete_node (heap, (fibnode_t) edge->aux);
|
|
edge->aux = NULL;
|
|
}
|
|
}
|
|
else if (edge->aux)
|
|
update_edge_key (heap, edge);
|
|
}
|
|
}
|
|
|
|
/* Recompute HEAP nodes for each uninlined call in NODE.
|
|
This is used when we know that edge badnesses are going only to increase
|
|
(we introduced new call site) and thus all we need is to insert newly
|
|
created edges into heap. */
|
|
|
|
static void
|
|
update_callee_keys (fibheap_t heap, struct cgraph_node *node,
|
|
bitmap updated_nodes)
|
|
{
|
|
struct cgraph_edge *e = node->callees;
|
|
|
|
if (!e)
|
|
return;
|
|
while (true)
|
|
if (!e->inline_failed && e->callee->callees)
|
|
e = e->callee->callees;
|
|
else
|
|
{
|
|
enum availability avail;
|
|
struct cgraph_node *callee;
|
|
/* We do not reset callee growth cache here. Since we added a new call,
|
|
growth chould have just increased and consequentely badness metric
|
|
don't need updating. */
|
|
if (e->inline_failed
|
|
&& (callee = cgraph_function_or_thunk_node (e->callee, &avail))
|
|
&& inline_summary (callee)->inlinable
|
|
&& cgraph_function_body_availability (callee) >= AVAIL_AVAILABLE
|
|
&& !bitmap_bit_p (updated_nodes, callee->uid))
|
|
{
|
|
if (can_inline_edge_p (e, false)
|
|
&& want_inline_small_function_p (e, false))
|
|
update_edge_key (heap, e);
|
|
else if (e->aux)
|
|
{
|
|
report_inline_failed_reason (e);
|
|
fibheap_delete_node (heap, (fibnode_t) e->aux);
|
|
e->aux = NULL;
|
|
}
|
|
}
|
|
if (e->next_callee)
|
|
e = e->next_callee;
|
|
else
|
|
{
|
|
do
|
|
{
|
|
if (e->caller == node)
|
|
return;
|
|
e = e->caller->callers;
|
|
}
|
|
while (!e->next_callee);
|
|
e = e->next_callee;
|
|
}
|
|
}
|
|
}
|
|
|
|
/* Enqueue all recursive calls from NODE into priority queue depending on
|
|
how likely we want to recursively inline the call. */
|
|
|
|
static void
|
|
lookup_recursive_calls (struct cgraph_node *node, struct cgraph_node *where,
|
|
fibheap_t heap)
|
|
{
|
|
struct cgraph_edge *e;
|
|
enum availability avail;
|
|
|
|
for (e = where->callees; e; e = e->next_callee)
|
|
if (e->callee == node
|
|
|| (cgraph_function_or_thunk_node (e->callee, &avail) == node
|
|
&& avail > AVAIL_OVERWRITABLE))
|
|
{
|
|
/* When profile feedback is available, prioritize by expected number
|
|
of calls. */
|
|
fibheap_insert (heap,
|
|
!max_count ? -e->frequency
|
|
: -(e->count / ((max_count + (1<<24) - 1) / (1<<24))),
|
|
e);
|
|
}
|
|
for (e = where->callees; e; e = e->next_callee)
|
|
if (!e->inline_failed)
|
|
lookup_recursive_calls (node, e->callee, heap);
|
|
}
|
|
|
|
/* Decide on recursive inlining: in the case function has recursive calls,
|
|
inline until body size reaches given argument. If any new indirect edges
|
|
are discovered in the process, add them to *NEW_EDGES, unless NEW_EDGES
|
|
is NULL. */
|
|
|
|
static bool
|
|
recursive_inlining (struct cgraph_edge *edge,
|
|
vec<cgraph_edge_p> *new_edges)
|
|
{
|
|
int limit = PARAM_VALUE (PARAM_MAX_INLINE_INSNS_RECURSIVE_AUTO);
|
|
fibheap_t heap;
|
|
struct cgraph_node *node;
|
|
struct cgraph_edge *e;
|
|
struct cgraph_node *master_clone = NULL, *next;
|
|
int depth = 0;
|
|
int n = 0;
|
|
|
|
node = edge->caller;
|
|
if (node->global.inlined_to)
|
|
node = node->global.inlined_to;
|
|
|
|
if (DECL_DECLARED_INLINE_P (node->symbol.decl))
|
|
limit = PARAM_VALUE (PARAM_MAX_INLINE_INSNS_RECURSIVE);
|
|
|
|
/* Make sure that function is small enough to be considered for inlining. */
|
|
if (estimate_size_after_inlining (node, edge) >= limit)
|
|
return false;
|
|
heap = fibheap_new ();
|
|
lookup_recursive_calls (node, node, heap);
|
|
if (fibheap_empty (heap))
|
|
{
|
|
fibheap_delete (heap);
|
|
return false;
|
|
}
|
|
|
|
if (dump_file)
|
|
fprintf (dump_file,
|
|
" Performing recursive inlining on %s\n",
|
|
cgraph_node_name (node));
|
|
|
|
/* Do the inlining and update list of recursive call during process. */
|
|
while (!fibheap_empty (heap))
|
|
{
|
|
struct cgraph_edge *curr
|
|
= (struct cgraph_edge *) fibheap_extract_min (heap);
|
|
struct cgraph_node *cnode, *dest = curr->callee;
|
|
|
|
if (!can_inline_edge_p (curr, true))
|
|
continue;
|
|
|
|
/* MASTER_CLONE is produced in the case we already started modified
|
|
the function. Be sure to redirect edge to the original body before
|
|
estimating growths otherwise we will be seeing growths after inlining
|
|
the already modified body. */
|
|
if (master_clone)
|
|
{
|
|
cgraph_redirect_edge_callee (curr, master_clone);
|
|
reset_edge_growth_cache (curr);
|
|
}
|
|
|
|
if (estimate_size_after_inlining (node, curr) > limit)
|
|
{
|
|
cgraph_redirect_edge_callee (curr, dest);
|
|
reset_edge_growth_cache (curr);
|
|
break;
|
|
}
|
|
|
|
depth = 1;
|
|
for (cnode = curr->caller;
|
|
cnode->global.inlined_to; cnode = cnode->callers->caller)
|
|
if (node->symbol.decl
|
|
== cgraph_function_or_thunk_node (curr->callee, NULL)->symbol.decl)
|
|
depth++;
|
|
|
|
if (!want_inline_self_recursive_call_p (curr, node, false, depth))
|
|
{
|
|
cgraph_redirect_edge_callee (curr, dest);
|
|
reset_edge_growth_cache (curr);
|
|
continue;
|
|
}
|
|
|
|
if (dump_file)
|
|
{
|
|
fprintf (dump_file,
|
|
" Inlining call of depth %i", depth);
|
|
if (node->count)
|
|
{
|
|
fprintf (dump_file, " called approx. %.2f times per call",
|
|
(double)curr->count / node->count);
|
|
}
|
|
fprintf (dump_file, "\n");
|
|
}
|
|
if (!master_clone)
|
|
{
|
|
/* We need original clone to copy around. */
|
|
master_clone = cgraph_clone_node (node, node->symbol.decl,
|
|
node->count, CGRAPH_FREQ_BASE,
|
|
false, vNULL, true);
|
|
for (e = master_clone->callees; e; e = e->next_callee)
|
|
if (!e->inline_failed)
|
|
clone_inlined_nodes (e, true, false, NULL);
|
|
cgraph_redirect_edge_callee (curr, master_clone);
|
|
reset_edge_growth_cache (curr);
|
|
}
|
|
|
|
inline_call (curr, false, new_edges, &overall_size, true);
|
|
lookup_recursive_calls (node, curr->callee, heap);
|
|
n++;
|
|
}
|
|
|
|
if (!fibheap_empty (heap) && dump_file)
|
|
fprintf (dump_file, " Recursive inlining growth limit met.\n");
|
|
fibheap_delete (heap);
|
|
|
|
if (!master_clone)
|
|
return false;
|
|
|
|
if (dump_file)
|
|
fprintf (dump_file,
|
|
"\n Inlined %i times, "
|
|
"body grown from size %i to %i, time %i to %i\n", n,
|
|
inline_summary (master_clone)->size, inline_summary (node)->size,
|
|
inline_summary (master_clone)->time, inline_summary (node)->time);
|
|
|
|
/* Remove master clone we used for inlining. We rely that clones inlined
|
|
into master clone gets queued just before master clone so we don't
|
|
need recursion. */
|
|
for (node = cgraph_first_function (); node != master_clone;
|
|
node = next)
|
|
{
|
|
next = cgraph_next_function (node);
|
|
if (node->global.inlined_to == master_clone)
|
|
cgraph_remove_node (node);
|
|
}
|
|
cgraph_remove_node (master_clone);
|
|
return true;
|
|
}
|
|
|
|
|
|
/* Given whole compilation unit estimate of INSNS, compute how large we can
|
|
allow the unit to grow. */
|
|
|
|
static int
|
|
compute_max_insns (int insns)
|
|
{
|
|
int max_insns = insns;
|
|
if (max_insns < PARAM_VALUE (PARAM_LARGE_UNIT_INSNS))
|
|
max_insns = PARAM_VALUE (PARAM_LARGE_UNIT_INSNS);
|
|
|
|
return ((HOST_WIDEST_INT) max_insns
|
|
* (100 + PARAM_VALUE (PARAM_INLINE_UNIT_GROWTH)) / 100);
|
|
}
|
|
|
|
|
|
/* Compute badness of all edges in NEW_EDGES and add them to the HEAP. */
|
|
|
|
static void
|
|
add_new_edges_to_heap (fibheap_t heap, vec<cgraph_edge_p> new_edges)
|
|
{
|
|
while (new_edges.length () > 0)
|
|
{
|
|
struct cgraph_edge *edge = new_edges.pop ();
|
|
|
|
gcc_assert (!edge->aux);
|
|
if (edge->inline_failed
|
|
&& can_inline_edge_p (edge, true)
|
|
&& want_inline_small_function_p (edge, true))
|
|
edge->aux = fibheap_insert (heap, edge_badness (edge, false), edge);
|
|
}
|
|
}
|
|
|
|
|
|
/* We use greedy algorithm for inlining of small functions:
|
|
All inline candidates are put into prioritized heap ordered in
|
|
increasing badness.
|
|
|
|
The inlining of small functions is bounded by unit growth parameters. */
|
|
|
|
static void
|
|
inline_small_functions (void)
|
|
{
|
|
struct cgraph_node *node;
|
|
struct cgraph_edge *edge;
|
|
fibheap_t edge_heap = fibheap_new ();
|
|
bitmap updated_nodes = BITMAP_ALLOC (NULL);
|
|
int min_size, max_size;
|
|
vec<cgraph_edge_p> new_indirect_edges = vNULL;
|
|
int initial_size = 0;
|
|
struct cgraph_node **order = XCNEWVEC (struct cgraph_node *, cgraph_n_nodes);
|
|
|
|
if (flag_indirect_inlining)
|
|
new_indirect_edges.create (8);
|
|
|
|
/* Compute overall unit size and other global parameters used by badness
|
|
metrics. */
|
|
|
|
max_count = 0;
|
|
ipa_reduced_postorder (order, true, true, NULL);
|
|
free (order);
|
|
|
|
FOR_EACH_DEFINED_FUNCTION (node)
|
|
if (!node->global.inlined_to)
|
|
{
|
|
if (cgraph_function_with_gimple_body_p (node)
|
|
|| node->thunk.thunk_p)
|
|
{
|
|
struct inline_summary *info = inline_summary (node);
|
|
struct ipa_dfs_info *dfs = (struct ipa_dfs_info *) node->symbol.aux;
|
|
|
|
if (!DECL_EXTERNAL (node->symbol.decl))
|
|
initial_size += info->size;
|
|
info->growth = estimate_growth (node);
|
|
if (dfs && dfs->next_cycle)
|
|
{
|
|
struct cgraph_node *n2;
|
|
int id = dfs->scc_no + 1;
|
|
for (n2 = node; n2;
|
|
n2 = ((struct ipa_dfs_info *) node->symbol.aux)->next_cycle)
|
|
{
|
|
struct inline_summary *info2 = inline_summary (n2);
|
|
if (info2->scc_no)
|
|
break;
|
|
info2->scc_no = id;
|
|
}
|
|
}
|
|
}
|
|
|
|
for (edge = node->callers; edge; edge = edge->next_caller)
|
|
if (max_count < edge->count)
|
|
max_count = edge->count;
|
|
}
|
|
ipa_free_postorder_info ();
|
|
initialize_growth_caches ();
|
|
|
|
if (dump_file)
|
|
fprintf (dump_file,
|
|
"\nDeciding on inlining of small functions. Starting with size %i.\n",
|
|
initial_size);
|
|
|
|
overall_size = initial_size;
|
|
max_size = compute_max_insns (overall_size);
|
|
min_size = overall_size;
|
|
|
|
/* Populate the heeap with all edges we might inline. */
|
|
|
|
FOR_EACH_DEFINED_FUNCTION (node)
|
|
if (!node->global.inlined_to)
|
|
{
|
|
if (dump_file)
|
|
fprintf (dump_file, "Enqueueing calls of %s/%i.\n",
|
|
cgraph_node_name (node), node->uid);
|
|
|
|
for (edge = node->callers; edge; edge = edge->next_caller)
|
|
if (edge->inline_failed
|
|
&& can_inline_edge_p (edge, true)
|
|
&& want_inline_small_function_p (edge, true)
|
|
&& edge->inline_failed)
|
|
{
|
|
gcc_assert (!edge->aux);
|
|
update_edge_key (edge_heap, edge);
|
|
}
|
|
}
|
|
|
|
gcc_assert (in_lto_p
|
|
|| !max_count
|
|
|| (profile_info && flag_branch_probabilities));
|
|
|
|
while (!fibheap_empty (edge_heap))
|
|
{
|
|
int old_size = overall_size;
|
|
struct cgraph_node *where, *callee;
|
|
int badness = fibheap_min_key (edge_heap);
|
|
int current_badness;
|
|
int cached_badness;
|
|
int growth;
|
|
|
|
edge = (struct cgraph_edge *) fibheap_extract_min (edge_heap);
|
|
gcc_assert (edge->aux);
|
|
edge->aux = NULL;
|
|
if (!edge->inline_failed)
|
|
continue;
|
|
|
|
/* Be sure that caches are maintained consistent.
|
|
We can not make this ENABLE_CHECKING only because it cause different
|
|
updates of the fibheap queue. */
|
|
cached_badness = edge_badness (edge, false);
|
|
reset_edge_growth_cache (edge);
|
|
reset_node_growth_cache (edge->callee);
|
|
|
|
/* When updating the edge costs, we only decrease badness in the keys.
|
|
Increases of badness are handled lazilly; when we see key with out
|
|
of date value on it, we re-insert it now. */
|
|
current_badness = edge_badness (edge, false);
|
|
gcc_assert (cached_badness == current_badness);
|
|
gcc_assert (current_badness >= badness);
|
|
if (current_badness != badness)
|
|
{
|
|
edge->aux = fibheap_insert (edge_heap, current_badness, edge);
|
|
continue;
|
|
}
|
|
|
|
if (!can_inline_edge_p (edge, true))
|
|
continue;
|
|
|
|
callee = cgraph_function_or_thunk_node (edge->callee, NULL);
|
|
growth = estimate_edge_growth (edge);
|
|
if (dump_file)
|
|
{
|
|
fprintf (dump_file,
|
|
"\nConsidering %s with %i size\n",
|
|
cgraph_node_name (callee),
|
|
inline_summary (callee)->size);
|
|
fprintf (dump_file,
|
|
" to be inlined into %s in %s:%i\n"
|
|
" Estimated growth after inlined into all is %+i insns.\n"
|
|
" Estimated badness is %i, frequency %.2f.\n",
|
|
cgraph_node_name (edge->caller),
|
|
flag_wpa ? "unknown"
|
|
: gimple_filename ((const_gimple) edge->call_stmt),
|
|
flag_wpa ? -1
|
|
: gimple_lineno ((const_gimple) edge->call_stmt),
|
|
estimate_growth (callee),
|
|
badness,
|
|
edge->frequency / (double)CGRAPH_FREQ_BASE);
|
|
if (edge->count)
|
|
fprintf (dump_file," Called "HOST_WIDEST_INT_PRINT_DEC"x\n",
|
|
edge->count);
|
|
if (dump_flags & TDF_DETAILS)
|
|
edge_badness (edge, true);
|
|
}
|
|
|
|
if (overall_size + growth > max_size
|
|
&& !DECL_DISREGARD_INLINE_LIMITS (callee->symbol.decl))
|
|
{
|
|
edge->inline_failed = CIF_INLINE_UNIT_GROWTH_LIMIT;
|
|
report_inline_failed_reason (edge);
|
|
continue;
|
|
}
|
|
|
|
if (!want_inline_small_function_p (edge, true))
|
|
continue;
|
|
|
|
/* Heuristics for inlining small functions works poorly for
|
|
recursive calls where we do efect similar to loop unrolling.
|
|
When inliing such edge seems profitable, leave decision on
|
|
specific inliner. */
|
|
if (cgraph_edge_recursive_p (edge))
|
|
{
|
|
where = edge->caller;
|
|
if (where->global.inlined_to)
|
|
where = where->global.inlined_to;
|
|
if (!recursive_inlining (edge,
|
|
flag_indirect_inlining
|
|
? &new_indirect_edges : NULL))
|
|
{
|
|
edge->inline_failed = CIF_RECURSIVE_INLINING;
|
|
continue;
|
|
}
|
|
reset_edge_caches (where);
|
|
/* Recursive inliner inlines all recursive calls of the function
|
|
at once. Consequently we need to update all callee keys. */
|
|
if (flag_indirect_inlining)
|
|
add_new_edges_to_heap (edge_heap, new_indirect_edges);
|
|
update_callee_keys (edge_heap, where, updated_nodes);
|
|
}
|
|
else
|
|
{
|
|
struct cgraph_node *outer_node = NULL;
|
|
int depth = 0;
|
|
|
|
/* Consider the case where self recursive function A is inlined into B.
|
|
This is desired optimization in some cases, since it leads to effect
|
|
similar of loop peeling and we might completely optimize out the
|
|
recursive call. However we must be extra selective. */
|
|
|
|
where = edge->caller;
|
|
while (where->global.inlined_to)
|
|
{
|
|
if (where->symbol.decl == callee->symbol.decl)
|
|
outer_node = where, depth++;
|
|
where = where->callers->caller;
|
|
}
|
|
if (outer_node
|
|
&& !want_inline_self_recursive_call_p (edge, outer_node,
|
|
true, depth))
|
|
{
|
|
edge->inline_failed
|
|
= (DECL_DISREGARD_INLINE_LIMITS (edge->callee->symbol.decl)
|
|
? CIF_RECURSIVE_INLINING : CIF_UNSPECIFIED);
|
|
continue;
|
|
}
|
|
else if (depth && dump_file)
|
|
fprintf (dump_file, " Peeling recursion with depth %i\n", depth);
|
|
|
|
gcc_checking_assert (!callee->global.inlined_to);
|
|
inline_call (edge, true, &new_indirect_edges, &overall_size, true);
|
|
if (flag_indirect_inlining)
|
|
add_new_edges_to_heap (edge_heap, new_indirect_edges);
|
|
|
|
reset_edge_caches (edge->callee);
|
|
reset_node_growth_cache (callee);
|
|
|
|
update_callee_keys (edge_heap, where, updated_nodes);
|
|
}
|
|
where = edge->caller;
|
|
if (where->global.inlined_to)
|
|
where = where->global.inlined_to;
|
|
|
|
/* Our profitability metric can depend on local properties
|
|
such as number of inlinable calls and size of the function body.
|
|
After inlining these properties might change for the function we
|
|
inlined into (since it's body size changed) and for the functions
|
|
called by function we inlined (since number of it inlinable callers
|
|
might change). */
|
|
update_caller_keys (edge_heap, where, updated_nodes, NULL);
|
|
bitmap_clear (updated_nodes);
|
|
|
|
if (dump_file)
|
|
{
|
|
fprintf (dump_file,
|
|
" Inlined into %s which now has time %i and size %i,"
|
|
"net change of %+i.\n",
|
|
cgraph_node_name (edge->caller),
|
|
inline_summary (edge->caller)->time,
|
|
inline_summary (edge->caller)->size,
|
|
overall_size - old_size);
|
|
}
|
|
if (min_size > overall_size)
|
|
{
|
|
min_size = overall_size;
|
|
max_size = compute_max_insns (min_size);
|
|
|
|
if (dump_file)
|
|
fprintf (dump_file, "New minimal size reached: %i\n", min_size);
|
|
}
|
|
}
|
|
|
|
free_growth_caches ();
|
|
new_indirect_edges.release ();
|
|
fibheap_delete (edge_heap);
|
|
if (dump_file)
|
|
fprintf (dump_file,
|
|
"Unit growth for small function inlining: %i->%i (%i%%)\n",
|
|
initial_size, overall_size,
|
|
initial_size ? overall_size * 100 / (initial_size) - 100: 0);
|
|
BITMAP_FREE (updated_nodes);
|
|
}
|
|
|
|
/* Flatten NODE. Performed both during early inlining and
|
|
at IPA inlining time. */
|
|
|
|
static void
|
|
flatten_function (struct cgraph_node *node, bool early)
|
|
{
|
|
struct cgraph_edge *e;
|
|
|
|
/* We shouldn't be called recursively when we are being processed. */
|
|
gcc_assert (node->symbol.aux == NULL);
|
|
|
|
node->symbol.aux = (void *) node;
|
|
|
|
for (e = node->callees; e; e = e->next_callee)
|
|
{
|
|
struct cgraph_node *orig_callee;
|
|
struct cgraph_node *callee = cgraph_function_or_thunk_node (e->callee, NULL);
|
|
|
|
/* We've hit cycle? It is time to give up. */
|
|
if (callee->symbol.aux)
|
|
{
|
|
if (dump_file)
|
|
fprintf (dump_file,
|
|
"Not inlining %s into %s to avoid cycle.\n",
|
|
xstrdup (cgraph_node_name (callee)),
|
|
xstrdup (cgraph_node_name (e->caller)));
|
|
e->inline_failed = CIF_RECURSIVE_INLINING;
|
|
continue;
|
|
}
|
|
|
|
/* When the edge is already inlined, we just need to recurse into
|
|
it in order to fully flatten the leaves. */
|
|
if (!e->inline_failed)
|
|
{
|
|
flatten_function (callee, early);
|
|
continue;
|
|
}
|
|
|
|
/* Flatten attribute needs to be processed during late inlining. For
|
|
extra code quality we however do flattening during early optimization,
|
|
too. */
|
|
if (!early
|
|
? !can_inline_edge_p (e, true)
|
|
: !can_early_inline_edge_p (e))
|
|
continue;
|
|
|
|
if (cgraph_edge_recursive_p (e))
|
|
{
|
|
if (dump_file)
|
|
fprintf (dump_file, "Not inlining: recursive call.\n");
|
|
continue;
|
|
}
|
|
|
|
if (gimple_in_ssa_p (DECL_STRUCT_FUNCTION (node->symbol.decl))
|
|
!= gimple_in_ssa_p (DECL_STRUCT_FUNCTION (callee->symbol.decl)))
|
|
{
|
|
if (dump_file)
|
|
fprintf (dump_file, "Not inlining: SSA form does not match.\n");
|
|
continue;
|
|
}
|
|
|
|
/* Inline the edge and flatten the inline clone. Avoid
|
|
recursing through the original node if the node was cloned. */
|
|
if (dump_file)
|
|
fprintf (dump_file, " Inlining %s into %s.\n",
|
|
xstrdup (cgraph_node_name (callee)),
|
|
xstrdup (cgraph_node_name (e->caller)));
|
|
orig_callee = callee;
|
|
inline_call (e, true, NULL, NULL, false);
|
|
if (e->callee != orig_callee)
|
|
orig_callee->symbol.aux = (void *) node;
|
|
flatten_function (e->callee, early);
|
|
if (e->callee != orig_callee)
|
|
orig_callee->symbol.aux = NULL;
|
|
}
|
|
|
|
node->symbol.aux = NULL;
|
|
if (!node->global.inlined_to)
|
|
inline_update_overall_summary (node);
|
|
}
|
|
|
|
/* Decide on the inlining. We do so in the topological order to avoid
|
|
expenses on updating data structures. */
|
|
|
|
static unsigned int
|
|
ipa_inline (void)
|
|
{
|
|
struct cgraph_node *node;
|
|
int nnodes;
|
|
struct cgraph_node **order =
|
|
XCNEWVEC (struct cgraph_node *, cgraph_n_nodes);
|
|
int i;
|
|
|
|
if (in_lto_p && optimize)
|
|
ipa_update_after_lto_read ();
|
|
|
|
if (dump_file)
|
|
dump_inline_summaries (dump_file);
|
|
|
|
nnodes = ipa_reverse_postorder (order);
|
|
|
|
FOR_EACH_FUNCTION (node)
|
|
node->symbol.aux = 0;
|
|
|
|
if (dump_file)
|
|
fprintf (dump_file, "\nFlattening functions:\n");
|
|
|
|
/* In the first pass handle functions to be flattened. Do this with
|
|
a priority so none of our later choices will make this impossible. */
|
|
for (i = nnodes - 1; i >= 0; i--)
|
|
{
|
|
node = order[i];
|
|
|
|
/* Handle nodes to be flattened.
|
|
Ideally when processing callees we stop inlining at the
|
|
entry of cycles, possibly cloning that entry point and
|
|
try to flatten itself turning it into a self-recursive
|
|
function. */
|
|
if (lookup_attribute ("flatten",
|
|
DECL_ATTRIBUTES (node->symbol.decl)) != NULL)
|
|
{
|
|
if (dump_file)
|
|
fprintf (dump_file,
|
|
"Flattening %s\n", cgraph_node_name (node));
|
|
flatten_function (node, false);
|
|
}
|
|
}
|
|
|
|
inline_small_functions ();
|
|
symtab_remove_unreachable_nodes (false, dump_file);
|
|
free (order);
|
|
|
|
/* Inline functions with a property that after inlining into all callers the
|
|
code size will shrink because the out-of-line copy is eliminated.
|
|
We do this regardless on the callee size as long as function growth limits
|
|
are met. */
|
|
if (flag_inline_functions_called_once)
|
|
{
|
|
int cold;
|
|
if (dump_file)
|
|
fprintf (dump_file,
|
|
"\nDeciding on functions to be inlined into all callers:\n");
|
|
|
|
/* Inlining one function called once has good chance of preventing
|
|
inlining other function into the same callee. Ideally we should
|
|
work in priority order, but probably inlining hot functions first
|
|
is good cut without the extra pain of maintaining the queue.
|
|
|
|
??? this is not really fitting the bill perfectly: inlining function
|
|
into callee often leads to better optimization of callee due to
|
|
increased context for optimization.
|
|
For example if main() function calls a function that outputs help
|
|
and then function that does the main optmization, we should inline
|
|
the second with priority even if both calls are cold by themselves.
|
|
|
|
We probably want to implement new predicate replacing our use of
|
|
maybe_hot_edge interpreted as maybe_hot_edge || callee is known
|
|
to be hot. */
|
|
for (cold = 0; cold <= 1; cold ++)
|
|
{
|
|
FOR_EACH_DEFINED_FUNCTION (node)
|
|
{
|
|
if (want_inline_function_to_all_callers_p (node, cold))
|
|
{
|
|
int num_calls = 0;
|
|
struct cgraph_edge *e;
|
|
for (e = node->callers; e; e = e->next_caller)
|
|
num_calls++;
|
|
while (node->callers && !node->global.inlined_to)
|
|
{
|
|
struct cgraph_node *caller = node->callers->caller;
|
|
|
|
if (dump_file)
|
|
{
|
|
fprintf (dump_file,
|
|
"\nInlining %s size %i.\n",
|
|
cgraph_node_name (node),
|
|
inline_summary (node)->size);
|
|
fprintf (dump_file,
|
|
" Called once from %s %i insns.\n",
|
|
cgraph_node_name (node->callers->caller),
|
|
inline_summary (node->callers->caller)->size);
|
|
}
|
|
|
|
inline_call (node->callers, true, NULL, NULL, true);
|
|
if (dump_file)
|
|
fprintf (dump_file,
|
|
" Inlined into %s which now has %i size\n",
|
|
cgraph_node_name (caller),
|
|
inline_summary (caller)->size);
|
|
if (!num_calls--)
|
|
{
|
|
if (dump_file)
|
|
fprintf (dump_file, "New calls found; giving up.\n");
|
|
break;
|
|
}
|
|
}
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
/* Free ipa-prop structures if they are no longer needed. */
|
|
if (optimize)
|
|
ipa_free_all_structures_after_iinln ();
|
|
|
|
if (dump_file)
|
|
fprintf (dump_file,
|
|
"\nInlined %i calls, eliminated %i functions\n\n",
|
|
ncalls_inlined, nfunctions_inlined);
|
|
|
|
if (dump_file)
|
|
dump_inline_summaries (dump_file);
|
|
/* In WPA we use inline summaries for partitioning process. */
|
|
if (!flag_wpa)
|
|
inline_free_summary ();
|
|
return 0;
|
|
}
|
|
|
|
/* Inline always-inline function calls in NODE. */
|
|
|
|
static bool
|
|
inline_always_inline_functions (struct cgraph_node *node)
|
|
{
|
|
struct cgraph_edge *e;
|
|
bool inlined = false;
|
|
|
|
for (e = node->callees; e; e = e->next_callee)
|
|
{
|
|
struct cgraph_node *callee = cgraph_function_or_thunk_node (e->callee, NULL);
|
|
if (!DECL_DISREGARD_INLINE_LIMITS (callee->symbol.decl))
|
|
continue;
|
|
|
|
if (cgraph_edge_recursive_p (e))
|
|
{
|
|
if (dump_file)
|
|
fprintf (dump_file, " Not inlining recursive call to %s.\n",
|
|
cgraph_node_name (e->callee));
|
|
e->inline_failed = CIF_RECURSIVE_INLINING;
|
|
continue;
|
|
}
|
|
|
|
if (!can_early_inline_edge_p (e))
|
|
continue;
|
|
|
|
if (dump_file)
|
|
fprintf (dump_file, " Inlining %s into %s (always_inline).\n",
|
|
xstrdup (cgraph_node_name (e->callee)),
|
|
xstrdup (cgraph_node_name (e->caller)));
|
|
inline_call (e, true, NULL, NULL, false);
|
|
inlined = true;
|
|
}
|
|
if (inlined)
|
|
inline_update_overall_summary (node);
|
|
|
|
return inlined;
|
|
}
|
|
|
|
/* Decide on the inlining. We do so in the topological order to avoid
|
|
expenses on updating data structures. */
|
|
|
|
static bool
|
|
early_inline_small_functions (struct cgraph_node *node)
|
|
{
|
|
struct cgraph_edge *e;
|
|
bool inlined = false;
|
|
|
|
for (e = node->callees; e; e = e->next_callee)
|
|
{
|
|
struct cgraph_node *callee = cgraph_function_or_thunk_node (e->callee, NULL);
|
|
if (!inline_summary (callee)->inlinable
|
|
|| !e->inline_failed)
|
|
continue;
|
|
|
|
/* Do not consider functions not declared inline. */
|
|
if (!DECL_DECLARED_INLINE_P (callee->symbol.decl)
|
|
&& !flag_inline_small_functions
|
|
&& !flag_inline_functions)
|
|
continue;
|
|
|
|
if (dump_file)
|
|
fprintf (dump_file, "Considering inline candidate %s.\n",
|
|
cgraph_node_name (callee));
|
|
|
|
if (!can_early_inline_edge_p (e))
|
|
continue;
|
|
|
|
if (cgraph_edge_recursive_p (e))
|
|
{
|
|
if (dump_file)
|
|
fprintf (dump_file, " Not inlining: recursive call.\n");
|
|
continue;
|
|
}
|
|
|
|
if (!want_early_inline_function_p (e))
|
|
continue;
|
|
|
|
if (dump_file)
|
|
fprintf (dump_file, " Inlining %s into %s.\n",
|
|
xstrdup (cgraph_node_name (callee)),
|
|
xstrdup (cgraph_node_name (e->caller)));
|
|
inline_call (e, true, NULL, NULL, true);
|
|
inlined = true;
|
|
}
|
|
|
|
return inlined;
|
|
}
|
|
|
|
/* Do inlining of small functions. Doing so early helps profiling and other
|
|
passes to be somewhat more effective and avoids some code duplication in
|
|
later real inlining pass for testcases with very many function calls. */
|
|
static unsigned int
|
|
early_inliner (void)
|
|
{
|
|
struct cgraph_node *node = cgraph_get_node (current_function_decl);
|
|
struct cgraph_edge *edge;
|
|
unsigned int todo = 0;
|
|
int iterations = 0;
|
|
bool inlined = false;
|
|
|
|
if (seen_error ())
|
|
return 0;
|
|
|
|
/* Do nothing if datastructures for ipa-inliner are already computed. This
|
|
happens when some pass decides to construct new function and
|
|
cgraph_add_new_function calls lowering passes and early optimization on
|
|
it. This may confuse ourself when early inliner decide to inline call to
|
|
function clone, because function clones don't have parameter list in
|
|
ipa-prop matching their signature. */
|
|
if (ipa_node_params_vector.exists ())
|
|
return 0;
|
|
|
|
#ifdef ENABLE_CHECKING
|
|
verify_cgraph_node (node);
|
|
#endif
|
|
|
|
/* Even when not optimizing or not inlining inline always-inline
|
|
functions. */
|
|
inlined = inline_always_inline_functions (node);
|
|
|
|
if (!optimize
|
|
|| flag_no_inline
|
|
|| !flag_early_inlining
|
|
/* Never inline regular functions into always-inline functions
|
|
during incremental inlining. This sucks as functions calling
|
|
always inline functions will get less optimized, but at the
|
|
same time inlining of functions calling always inline
|
|
function into an always inline function might introduce
|
|
cycles of edges to be always inlined in the callgraph.
|
|
|
|
We might want to be smarter and just avoid this type of inlining. */
|
|
|| DECL_DISREGARD_INLINE_LIMITS (node->symbol.decl))
|
|
;
|
|
else if (lookup_attribute ("flatten",
|
|
DECL_ATTRIBUTES (node->symbol.decl)) != NULL)
|
|
{
|
|
/* When the function is marked to be flattened, recursively inline
|
|
all calls in it. */
|
|
if (dump_file)
|
|
fprintf (dump_file,
|
|
"Flattening %s\n", cgraph_node_name (node));
|
|
flatten_function (node, true);
|
|
inlined = true;
|
|
}
|
|
else
|
|
{
|
|
/* We iterate incremental inlining to get trivial cases of indirect
|
|
inlining. */
|
|
while (iterations < PARAM_VALUE (PARAM_EARLY_INLINER_MAX_ITERATIONS)
|
|
&& early_inline_small_functions (node))
|
|
{
|
|
timevar_push (TV_INTEGRATION);
|
|
todo |= optimize_inline_calls (current_function_decl);
|
|
|
|
/* Technically we ought to recompute inline parameters so the new
|
|
iteration of early inliner works as expected. We however have
|
|
values approximately right and thus we only need to update edge
|
|
info that might be cleared out for newly discovered edges. */
|
|
for (edge = node->callees; edge; edge = edge->next_callee)
|
|
{
|
|
struct inline_edge_summary *es = inline_edge_summary (edge);
|
|
es->call_stmt_size
|
|
= estimate_num_insns (edge->call_stmt, &eni_size_weights);
|
|
es->call_stmt_time
|
|
= estimate_num_insns (edge->call_stmt, &eni_time_weights);
|
|
if (edge->callee->symbol.decl
|
|
&& !gimple_check_call_matching_types (edge->call_stmt,
|
|
edge->callee->symbol.decl))
|
|
edge->call_stmt_cannot_inline_p = true;
|
|
}
|
|
timevar_pop (TV_INTEGRATION);
|
|
iterations++;
|
|
inlined = false;
|
|
}
|
|
if (dump_file)
|
|
fprintf (dump_file, "Iterations: %i\n", iterations);
|
|
}
|
|
|
|
if (inlined)
|
|
{
|
|
timevar_push (TV_INTEGRATION);
|
|
todo |= optimize_inline_calls (current_function_decl);
|
|
timevar_pop (TV_INTEGRATION);
|
|
}
|
|
|
|
cfun->always_inline_functions_inlined = true;
|
|
|
|
return todo;
|
|
}
|
|
|
|
struct gimple_opt_pass pass_early_inline =
|
|
{
|
|
{
|
|
GIMPLE_PASS,
|
|
"einline", /* name */
|
|
OPTGROUP_INLINE, /* optinfo_flags */
|
|
NULL, /* gate */
|
|
early_inliner, /* execute */
|
|
NULL, /* sub */
|
|
NULL, /* next */
|
|
0, /* static_pass_number */
|
|
TV_EARLY_INLINING, /* tv_id */
|
|
PROP_ssa, /* properties_required */
|
|
0, /* properties_provided */
|
|
0, /* properties_destroyed */
|
|
0, /* todo_flags_start */
|
|
0 /* todo_flags_finish */
|
|
}
|
|
};
|
|
|
|
|
|
/* When to run IPA inlining. Inlining of always-inline functions
|
|
happens during early inlining.
|
|
|
|
Enable inlining unconditoinally at -flto. We need size estimates to
|
|
drive partitioning. */
|
|
|
|
static bool
|
|
gate_ipa_inline (void)
|
|
{
|
|
return optimize || flag_lto || flag_wpa;
|
|
}
|
|
|
|
struct ipa_opt_pass_d pass_ipa_inline =
|
|
{
|
|
{
|
|
IPA_PASS,
|
|
"inline", /* name */
|
|
OPTGROUP_INLINE, /* optinfo_flags */
|
|
gate_ipa_inline, /* gate */
|
|
ipa_inline, /* execute */
|
|
NULL, /* sub */
|
|
NULL, /* next */
|
|
0, /* static_pass_number */
|
|
TV_IPA_INLINING, /* tv_id */
|
|
0, /* properties_required */
|
|
0, /* properties_provided */
|
|
0, /* properties_destroyed */
|
|
TODO_remove_functions, /* todo_flags_finish */
|
|
TODO_dump_symtab
|
|
| TODO_remove_functions | TODO_ggc_collect /* todo_flags_finish */
|
|
},
|
|
inline_generate_summary, /* generate_summary */
|
|
inline_write_summary, /* write_summary */
|
|
inline_read_summary, /* read_summary */
|
|
NULL, /* write_optimization_summary */
|
|
NULL, /* read_optimization_summary */
|
|
NULL, /* stmt_fixup */
|
|
0, /* TODOs */
|
|
inline_transform, /* function_transform */
|
|
NULL, /* variable_transform */
|
|
};
|