1 /* Definitions for branch prediction routines in the GNU compiler.
2 Copyright (C) 2001-2022 Free Software Foundation, Inc.
4 This file is part of GCC.
6 GCC is free software; you can redistribute it and/or modify it under
7 the terms of the GNU General Public License as published by the Free
8 Software Foundation; either version 3, or (at your option) any later
11 GCC is distributed in the hope that it will be useful, but WITHOUT ANY
12 WARRANTY; without even the implied warranty of MERCHANTABILITY or
13 FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
16 You should have received a copy of the GNU General Public License
17 along with GCC; see the file COPYING3. If not see
18 <http://www.gnu.org/licenses/>. */
23 #include "profile-count.h"
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 #define PROB_UNINITIALIZED (-1)
36 #define DEF_PREDICTOR(ENUM, NAME, HITRATE, FLAGS) ENUM,
39 #include "predict.def"
41 /* Upper bound on non-language-specific builtins. */
52 extern profile_probability split_branch_probability
;
54 extern gcov_type
get_hot_bb_threshold (void);
55 extern void set_hot_bb_threshold (gcov_type
);
56 extern bool maybe_hot_count_p (struct function
*, profile_count
);
57 extern bool maybe_hot_bb_p (struct function
*, const_basic_block
);
58 extern bool maybe_hot_edge_p (edge
);
59 extern bool probably_never_executed_bb_p (struct function
*, const_basic_block
);
60 extern bool probably_never_executed_edge_p (struct function
*, edge
);
61 extern enum optimize_size_level
optimize_function_for_size_p (struct function
*);
62 extern bool optimize_function_for_speed_p (struct function
*);
63 extern optimization_type
function_optimization_type (struct function
*);
64 extern enum optimize_size_level
optimize_bb_for_size_p (const_basic_block
);
65 extern bool optimize_bb_for_speed_p (const_basic_block
);
66 extern optimization_type
bb_optimization_type (const_basic_block
);
67 extern enum optimize_size_level
optimize_edge_for_size_p (edge
);
68 extern bool optimize_edge_for_speed_p (edge
);
69 extern enum optimize_size_level
optimize_insn_for_size_p (void);
70 extern bool optimize_insn_for_speed_p (void);
71 extern enum optimize_size_level
optimize_loop_for_size_p (class loop
*);
72 extern bool optimize_loop_for_speed_p (class loop
*);
73 extern bool optimize_loop_nest_for_speed_p (class loop
*);
74 extern enum optimize_size_level
optimize_loop_nest_for_size_p (class loop
*);
75 extern bool predictable_edge_p (edge
);
76 extern void rtl_profile_for_bb (basic_block
);
77 extern void rtl_profile_for_edge (edge
);
78 extern void default_rtl_profile (void);
79 extern bool rtl_predicted_by_p (const_basic_block
, enum br_predictor
);
80 extern bool gimple_predicted_by_p (const_basic_block
, enum br_predictor
);
81 extern bool edge_probability_reliable_p (const_edge
);
82 extern bool br_prob_note_reliable_p (const_rtx
);
83 extern void predict_insn_def (rtx_insn
*, enum br_predictor
, enum prediction
);
84 extern void rtl_predict_edge (edge
, enum br_predictor
, int);
85 extern void gimple_predict_edge (edge
, enum br_predictor
, int);
86 extern void remove_predictions_associated_with_edge (edge
);
87 extern void predict_edge_def (edge
, enum br_predictor
, enum prediction
);
88 extern void invert_br_probabilities (rtx
);
89 extern void guess_outgoing_edge_probabilities (basic_block
);
90 extern void tree_guess_outgoing_edge_probabilities (basic_block
);
91 extern void tree_estimate_probability (bool);
92 extern void handle_missing_profiles (void);
93 extern bool update_max_bb_count (void);
94 extern bool expensive_function_p (int);
95 extern void estimate_bb_frequencies (bool);
96 extern void compute_function_frequency (void);
97 extern tree
build_predict_expr (enum br_predictor
, enum prediction
);
98 extern const char *predictor_name (enum br_predictor
);
99 extern void rebuild_frequencies (void);
100 extern void report_predictor_hitrates (void);
101 extern void force_edge_cold (edge
, bool);
102 extern void propagate_unlikely_bbs_forward (void);
103 extern void change_edge_frequency (edge
, profile_probability
);
105 extern void add_reg_br_prob_note (rtx_insn
*, profile_probability
);
107 /* In ipa-pure-const.cc */
108 extern void warn_function_cold (tree
);
110 #endif /* GCC_PREDICT_H */