blob: b345bbc4fd7e75c0ff8bfa79c0c7619e16de1864 [file] [log] [blame]
/* IPA function body analysis.
Copyright (C) 2003-2017 Free Software Foundation, Inc.
Contributed by Jan Hubicka
This file is part of GCC.
GCC is free software; you can redistribute it and/or modify it under
the terms of the GNU General Public License as published by the Free
Software Foundation; either version 3, or (at your option) any later
version.
GCC is distributed in the hope that it will be useful, but WITHOUT ANY
WARRANTY; without even the implied warranty of MERCHANTABILITY or
FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
for more details.
You should have received a copy of the GNU General Public License
along with GCC; see the file COPYING3. If not see
<http://www.gnu.org/licenses/>. */
#ifndef GCC_IPA_SUMMARY_H
#define GCC_IPA_SUMMARY_H
#include "sreal.h"
#include "ipa-predicate.h"
/* Hints are reasons why IPA heuristics should preffer specializing given
function. They are represtented as bitmap of the following values. */
enum ipa_hints_vals {
/* When specialization turns indirect call into a direct call,
it is good idea to do so. */
INLINE_HINT_indirect_call = 1,
/* Inlining may make loop iterations or loop stride known. It is good idea
to do so because it enables loop optimizatoins. */
INLINE_HINT_loop_iterations = 2,
INLINE_HINT_loop_stride = 4,
/* Inlining within same strongly connected component of callgraph is often
a loss due to increased stack frame usage and prologue setup costs. */
INLINE_HINT_same_scc = 8,
/* Inlining functions in strongly connected component is not such a great
win. */
INLINE_HINT_in_scc = 16,
/* If function is declared inline by user, it may be good idea to inline
it. Set by simple_edge_hints in ipa-inline-analysis.c. */
INLINE_HINT_declared_inline = 32,
/* Programs are usually still organized for non-LTO compilation and thus
if functions are in different modules, inlining may not be so important.
Set by simple_edge_hints in ipa-inline-analysis.c. */
INLINE_HINT_cross_module = 64,
/* If array indexes of loads/stores become known there may be room for
further optimization. */
INLINE_HINT_array_index = 128,
/* We know that the callee is hot by profile. */
INLINE_HINT_known_hot = 256
};
typedef int ipa_hints;
/* Simple description of whether a memory load or a condition refers to a load
from an aggregate and if so, how and where from in the aggregate.
Individual fields have the same meaning like fields with the same name in
struct condition. */
struct agg_position_info
{
HOST_WIDE_INT offset;
bool agg_contents;
bool by_ref;
};
/* Representation of function body size and time depending on the call
context. We keep simple array of record, every containing of predicate
and time/size to account. */
struct GTY(()) size_time_entry
{
/* Predicate for code to be executed. */
predicate exec_predicate;
/* Predicate for value to be constant and optimized out in a specialized copy.
When deciding on specialization this makes it possible to see how much
the executed code paths will simplify. */
predicate nonconst_predicate;
int size;
sreal GTY((skip)) time;
};
/* Function inlining information. */
struct GTY(()) ipa_fn_summary
{
/* Information about the function body itself. */
/* Estimated stack frame consumption by the function. */
HOST_WIDE_INT estimated_self_stack_size;
/* Size of the function body. */
int self_size;
/* Minimal size increase after inlining. */
int min_size;
/* False when there something makes inlining impossible (such as va_arg). */
unsigned inlinable : 1;
/* True when function contains cilk spawn (and thus we can not inline
into it). */
unsigned contains_cilk_spawn : 1;
/* True wen there is only one caller of the function before small function
inlining. */
unsigned int single_caller : 1;
/* True if function contains any floating point expressions. */
unsigned int fp_expressions : 1;
/* Information about function that will result after applying all the
inline decisions present in the callgraph. Generally kept up to
date only for functions that are not inline clones. */
/* Estimated stack frame consumption by the function. */
HOST_WIDE_INT estimated_stack_size;
/* Expected offset of the stack frame of function. */
HOST_WIDE_INT stack_frame_offset;
/* Estimated size of the function after inlining. */
sreal GTY((skip)) time;
int size;
/* Conditional size/time information. The summaries are being
merged during inlining. */
conditions conds;
vec<size_time_entry, va_gc> *size_time_table;
/* Predicate on when some loop in the function becomes to have known
bounds. */
predicate * GTY((skip)) loop_iterations;
/* Predicate on when some loop in the function becomes to have known
stride. */
predicate * GTY((skip)) loop_stride;
/* Predicate on when some array indexes become constants. */
predicate * GTY((skip)) array_index;
/* Estimated growth for inlining all copies of the function before start
of small functions inlining.
This value will get out of date as the callers are duplicated, but
using up-to-date value in the badness metric mean a lot of extra
expenses. */
int growth;
/* Number of SCC on the beginning of inlining process. */
int scc_no;
/* Keep all field empty so summary dumping works during its computation.
This is useful for debugging. */
ipa_fn_summary ()
: estimated_self_stack_size (0), self_size (0), min_size (0),
inlinable (false), contains_cilk_spawn (false), single_caller (false),
fp_expressions (false), estimated_stack_size (false),
stack_frame_offset (false), time (0), size (0), conds (NULL),
size_time_table (NULL), loop_iterations (NULL), loop_stride (NULL),
array_index (NULL), growth (0), scc_no (0)
{
}
/* Record time and size under given predicates. */
void account_size_time (int, sreal, const predicate &, const predicate &);
/* Reset summary to empty state. */
void reset (struct cgraph_node *node);
/* We keep values scaled up, so fractional sizes can be accounted. */
static const int size_scale = 2;
};
class GTY((user)) ipa_fn_summary_t: public function_summary <ipa_fn_summary *>
{
public:
ipa_fn_summary_t (symbol_table *symtab, bool ggc):
function_summary <ipa_fn_summary *> (symtab, ggc) {}
static ipa_fn_summary_t *create_ggc (symbol_table *symtab)
{
struct ipa_fn_summary_t *summary = new (ggc_alloc <ipa_fn_summary_t> ())
ipa_fn_summary_t(symtab, true);
summary->disable_insertion_hook ();
return summary;
}
virtual void insert (cgraph_node *, ipa_fn_summary *);
virtual void remove (cgraph_node *node, ipa_fn_summary *);
virtual void duplicate (cgraph_node *src, cgraph_node *dst,
ipa_fn_summary *src_data, ipa_fn_summary *dst_data);
};
extern GTY(()) function_summary <ipa_fn_summary *> *ipa_fn_summaries;
/* Information kept about callgraph edges. */
struct ipa_call_summary
{
class predicate *predicate;
/* Vector indexed by parameters. */
vec<inline_param_summary> param;
/* Estimated size and time of the call statement. */
int call_stmt_size;
int call_stmt_time;
/* Depth of loop nest, 0 means no nesting. */
unsigned int loop_depth;
/* Indicates whether the caller returns the value of it's callee. */
bool is_return_callee_uncaptured;
/* Keep all field empty so summary dumping works during its computation.
This is useful for debugging. */
ipa_call_summary ()
: predicate (NULL), param (vNULL), call_stmt_size (0), call_stmt_time (0),
loop_depth (0)
{
}
/* Reset inline summary to empty state. */
void reset ();
};
class ipa_call_summary_t: public call_summary <ipa_call_summary *>
{
public:
ipa_call_summary_t (symbol_table *symtab, bool ggc):
call_summary <ipa_call_summary *> (symtab, ggc) {}
/* Hook that is called by summary when an edge is duplicated. */
virtual void remove (cgraph_edge *cs, ipa_call_summary *);
/* Hook that is called by summary when an edge is duplicated. */
virtual void duplicate (cgraph_edge *src, cgraph_edge *dst,
ipa_call_summary *src_data,
ipa_call_summary *dst_data);
};
extern call_summary <ipa_call_summary *> *ipa_call_summaries;
/* In ipa-fnsummary.c */
void ipa_debug_fn_summary (struct cgraph_node *);
void ipa_dump_fn_summaries (FILE *f);
void ipa_dump_fn_summary (FILE *f, struct cgraph_node *node);
void ipa_dump_hints (FILE *f, ipa_hints);
void ipa_free_fn_summary (void);
void inline_analyze_function (struct cgraph_node *node);
void estimate_ipcp_clone_size_and_time (struct cgraph_node *,
vec<tree>,
vec<ipa_polymorphic_call_context>,
vec<ipa_agg_jump_function_p>,
int *, sreal *, sreal *,
ipa_hints *);
void ipa_merge_fn_summary_after_inlining (struct cgraph_edge *edge);
void ipa_update_overall_fn_summary (struct cgraph_node *node);
void compute_fn_summary (struct cgraph_node *, bool);
void evaluate_properties_for_edge (struct cgraph_edge *e, bool inline_p,
clause_t *clause_ptr,
clause_t *nonspec_clause_ptr,
vec<tree> *known_vals_ptr,
vec<ipa_polymorphic_call_context>
*known_contexts_ptr,
vec<ipa_agg_jump_function_p> *);
void estimate_node_size_and_time (struct cgraph_node *node,
clause_t possible_truths,
clause_t nonspec_possible_truths,
vec<tree> known_vals,
vec<ipa_polymorphic_call_context>,
vec<ipa_agg_jump_function_p> known_aggs,
int *ret_size, int *ret_min_size,
sreal *ret_time,
sreal *ret_nonspecialized_time,
ipa_hints *ret_hints,
vec<inline_param_summary>
inline_param_summary);
void ipa_fnsummary_c_finalize (void);
#endif /* GCC_IPA_FNSUMMARY_H */