1/* Definitions for branch prediction routines in the GNU compiler.
2   Copyright (C) 2001-2015 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/* Random guesstimation given names.
24   PROB_VERY_UNLIKELY should be small enough so basic block predicted
25   by it gets below HOT_BB_FREQUENCY_FRACTION.  */
26#define PROB_VERY_UNLIKELY	(REG_BR_PROB_BASE / 2000 - 1)
27#define PROB_EVEN		(REG_BR_PROB_BASE / 2)
28#define PROB_VERY_LIKELY	(REG_BR_PROB_BASE - PROB_VERY_UNLIKELY)
29#define PROB_ALWAYS		(REG_BR_PROB_BASE)
30#define PROB_UNLIKELY           (REG_BR_PROB_BASE / 5 - 1)
31#define PROB_LIKELY             (REG_BR_PROB_BASE - PROB_UNLIKELY)
32
33#define DEF_PREDICTOR(ENUM, NAME, HITRATE, FLAGS) ENUM,
34enum br_predictor
35{
36#include "predict.def"
37
38  /* Upper bound on non-language-specific builtins.  */
39  END_PREDICTORS
40};
41#undef DEF_PREDICTOR
42enum prediction
43{
44   NOT_TAKEN,
45   TAKEN
46};
47
48extern gcov_type get_hot_bb_threshold (void);
49extern void set_hot_bb_threshold (gcov_type);
50extern bool maybe_hot_count_p (struct function *, gcov_type);
51extern bool maybe_hot_bb_p (struct function *, const_basic_block);
52extern bool maybe_hot_edge_p (edge);
53extern bool probably_never_executed_bb_p (struct function *, const_basic_block);
54extern bool probably_never_executed_edge_p (struct function *, edge);
55extern bool optimize_function_for_size_p (struct function *);
56extern bool optimize_function_for_speed_p (struct function *);
57extern bool optimize_bb_for_size_p (const_basic_block);
58extern bool optimize_bb_for_speed_p (const_basic_block);
59extern bool optimize_edge_for_size_p (edge);
60extern bool optimize_edge_for_speed_p (edge);
61extern bool optimize_insn_for_size_p (void);
62extern bool optimize_insn_for_speed_p (void);
63extern bool optimize_loop_for_size_p (struct loop *);
64extern bool optimize_loop_for_speed_p (struct loop *);
65extern bool optimize_loop_nest_for_speed_p (struct loop *);
66extern bool optimize_loop_nest_for_size_p (struct loop *);
67extern bool predictable_edge_p (edge);
68extern void rtl_profile_for_bb (basic_block);
69extern void rtl_profile_for_edge (edge);
70extern void default_rtl_profile (void);
71extern bool rtl_predicted_by_p (const_basic_block, enum br_predictor);
72extern bool gimple_predicted_by_p (const_basic_block, enum br_predictor);
73extern bool edge_probability_reliable_p (const_edge);
74extern bool br_prob_note_reliable_p (const_rtx);
75extern void predict_insn_def (rtx_insn *, enum br_predictor, enum prediction);
76extern void rtl_predict_edge (edge, enum br_predictor, int);
77extern void gimple_predict_edge (edge, enum br_predictor, int);
78extern void remove_predictions_associated_with_edge (edge);
79extern void predict_edge_def (edge, enum br_predictor, enum prediction);
80extern void invert_br_probabilities (rtx);
81extern void guess_outgoing_edge_probabilities (basic_block);
82extern void tree_estimate_probability (void);
83extern void handle_missing_profiles (void);
84extern int counts_to_freqs (void);
85extern bool expensive_function_p (int);
86extern void estimate_bb_frequencies (bool);
87extern void compute_function_frequency (void);
88extern tree build_predict_expr (enum br_predictor, enum prediction);
89extern const char *predictor_name (enum br_predictor);
90extern void rebuild_frequencies (void);
91
92#endif  /* GCC_PREDICT_H */
93