1/* Definitions for branch prediction routines in the GNU compiler.
2 Copyright (C) 2001-2017 Free Software Foundation, Inc.
3
4This file is part of GCC.
5
6GCC is free software; you can redistribute it and/or modify it under
7the terms of the GNU General Public License as published by the Free
8Software Foundation; either version 3, or (at your option) any later
9version.
10
11GCC is distributed in the hope that it will be useful, but WITHOUT ANY
12WARRANTY; without even the implied warranty of MERCHANTABILITY or
13FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
14for more details.
15
16You should have received a copy of the GNU General Public License
17along with GCC; see the file COPYING3. If not see
18<http://www.gnu.org/licenses/>. */
19
20#ifndef GCC_PREDICT_H
21#define GCC_PREDICT_H
22
23#include "profile-count.h"
24
25/* Random guesstimation given names.
26 PROB_VERY_UNLIKELY should be small enough so basic block predicted
27 by it gets below HOT_BB_FREQUENCY_FRACTION. */
28#define PROB_VERY_UNLIKELY (REG_BR_PROB_BASE / 2000 - 1)
29#define PROB_EVEN (REG_BR_PROB_BASE / 2)
30#define PROB_VERY_LIKELY (REG_BR_PROB_BASE - PROB_VERY_UNLIKELY)
31#define PROB_ALWAYS (REG_BR_PROB_BASE)
32#define PROB_UNLIKELY (REG_BR_PROB_BASE / 5 - 1)
33#define PROB_LIKELY (REG_BR_PROB_BASE - PROB_UNLIKELY)
34
35#define DEF_PREDICTOR(ENUM, NAME, HITRATE, FLAGS) ENUM,
36enum br_predictor
37{
38#include "predict.def"
39
40 /* Upper bound on non-language-specific builtins. */
41 END_PREDICTORS
42};
43#undef DEF_PREDICTOR
44enum prediction
45{
46 NOT_TAKEN,
47 TAKEN
48};
49
50/* In emit-rtl.c. */
51extern profile_probability split_branch_probability;
52
53extern gcov_type get_hot_bb_threshold (void);
54extern void set_hot_bb_threshold (gcov_type);
55extern bool maybe_hot_count_p (struct function *, profile_count);
56extern bool maybe_hot_bb_p (struct function *, const_basic_block);
57extern bool maybe_hot_edge_p (edge);
58extern bool probably_never_executed_bb_p (struct function *, const_basic_block);
59extern bool probably_never_executed_edge_p (struct function *, edge);
60extern bool optimize_function_for_size_p (struct function *);
61extern bool optimize_function_for_speed_p (struct function *);
62extern optimization_type function_optimization_type (struct function *);
63extern bool optimize_bb_for_size_p (const_basic_block);
64extern bool optimize_bb_for_speed_p (const_basic_block);
65extern optimization_type bb_optimization_type (const_basic_block);
66extern bool optimize_edge_for_size_p (edge);
67extern bool optimize_edge_for_speed_p (edge);
68extern bool optimize_insn_for_size_p (void);
69extern bool optimize_insn_for_speed_p (void);
70extern bool optimize_loop_for_size_p (struct loop *);
71extern bool optimize_loop_for_speed_p (struct loop *);
72extern bool optimize_loop_nest_for_speed_p (struct loop *);
73extern bool optimize_loop_nest_for_size_p (struct loop *);
74extern bool predictable_edge_p (edge);
75extern void rtl_profile_for_bb (basic_block);
76extern void rtl_profile_for_edge (edge);
77extern void default_rtl_profile (void);
78extern bool rtl_predicted_by_p (const_basic_block, enum br_predictor);
79extern bool gimple_predicted_by_p (const_basic_block, enum br_predictor);
80extern bool edge_probability_reliable_p (const_edge);
81extern bool br_prob_note_reliable_p (const_rtx);
82extern void predict_insn_def (rtx_insn *, enum br_predictor, enum prediction);
83extern void rtl_predict_edge (edge, enum br_predictor, int);
84extern void gimple_predict_edge (edge, enum br_predictor, int);
85extern void remove_predictions_associated_with_edge (edge);
86extern void predict_edge_def (edge, enum br_predictor, enum prediction);
87extern void invert_br_probabilities (rtx);
88extern void guess_outgoing_edge_probabilities (basic_block);
89extern void tree_guess_outgoing_edge_probabilities (basic_block);
90extern void tree_estimate_probability (bool);
91extern void handle_missing_profiles (void);
92extern bool update_max_bb_count (void);
93extern bool expensive_function_p (int);
94extern void estimate_bb_frequencies (bool);
95extern void compute_function_frequency (void);
96extern tree build_predict_expr (enum br_predictor, enum prediction);
97extern const char *predictor_name (enum br_predictor);
98extern void rebuild_frequencies (void);
99extern void report_predictor_hitrates (void);
100extern void force_edge_cold (edge, bool);
101extern void propagate_unlikely_bbs_forward (void);
102
103extern void add_reg_br_prob_note (rtx_insn *, profile_probability);
104
105/* In ipa-pure-const.c */
106extern void warn_function_cold (tree);
107
108#endif /* GCC_PREDICT_H */
109