xref: /openbsd-src/gnu/gcc/gcc/value-prof.h (revision 404b540a9034ac75a6199ad1a32d1bbc7a0d4210)
1 /* Definitions for transformations based on profile information for values.
2    Copyright (C) 2003, 2004, 2005 Free Software Foundation, Inc.
3 
4 This file is part of GCC.
5 
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 2, or (at your option) any later
9 version.
10 
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
14 for more details.
15 
16 You should have received a copy of the GNU General Public License
17 along with GCC; see the file COPYING.  If not, write to the Free
18 Software Foundation, 51 Franklin Street, Fifth Floor, Boston, MA
19 02110-1301, USA.  */
20 
21 #ifndef GCC_VALUE_PROF_H
22 #define GCC_VALUE_PROF_H
23 
24 /* Supported histogram types.  */
25 enum hist_type
26 {
27   HIST_TYPE_INTERVAL,	/* Measures histogram of values inside a specified
28 			   interval.  */
29   HIST_TYPE_POW2,	/* Histogram of power of 2 values.  */
30   HIST_TYPE_SINGLE_VALUE, /* Tries to identify the value that is (almost)
31 			   always constant.  */
32   HIST_TYPE_CONST_DELTA	/* Tries to identify the (almost) always constant
33 			   difference between two evaluations of a value.  */
34 };
35 
36 #define COUNTER_FOR_HIST_TYPE(TYPE) ((int) (TYPE) + GCOV_FIRST_VALUE_COUNTER)
37 #define HIST_TYPE_FOR_COUNTER(COUNTER) \
38   ((enum hist_type) ((COUNTER) - GCOV_FIRST_VALUE_COUNTER))
39 
40 /* The value to measure.  */
41 struct histogram_value_t
42 {
43   struct
44     {
45       tree value;		/* The value to profile.  */
46       tree stmt;		/* Insn containing the value.  */
47       gcov_type *counters;		        /* Pointer to first counter.  */
48       struct histogram_value_t *next;		/* Linked list pointer.  */
49     } hvalue;
50   enum hist_type type;			/* Type of information to measure.  */
51   unsigned n_counters;			/* Number of required counters.  */
52   union
53     {
54       struct
55 	{
56 	  int int_start;	/* First value in interval.  */
57 	  unsigned int steps;	/* Number of values in it.  */
58 	} intvl;	/* Interval histogram data.  */
59     } hdata;		/* Profiled information specific data.  */
60 };
61 
62 typedef struct histogram_value_t *histogram_value;
63 
64 DEF_VEC_P(histogram_value);
65 DEF_VEC_ALLOC_P(histogram_value,heap);
66 
67 typedef VEC(histogram_value,heap) *histogram_values;
68 
69 /* Hooks registration.  */
70 extern void tree_register_value_prof_hooks (void);
71 
72 /* IR-independent entry points.  */
73 extern void find_values_to_profile (histogram_values *);
74 extern bool value_profile_transformations (void);
75 
76 /* External declarations for edge-based profiling.  */
77 struct profile_hooks {
78 
79   /* Insert code to initialize edge profiler.  */
80   void (*init_edge_profiler) (void);
81 
82   /* Insert code to increment an edge count.  */
83   void (*gen_edge_profiler) (int, edge);
84 
85   /* Insert code to increment the interval histogram counter.  */
86   void (*gen_interval_profiler) (histogram_value, unsigned, unsigned);
87 
88   /* Insert code to increment the power of two histogram counter.  */
89   void (*gen_pow2_profiler) (histogram_value, unsigned, unsigned);
90 
91   /* Insert code to find the most common value.  */
92   void (*gen_one_value_profiler) (histogram_value, unsigned, unsigned);
93 
94   /* Insert code to find the most common value of a difference between two
95      evaluations of an expression.  */
96   void (*gen_const_delta_profiler) (histogram_value, unsigned, unsigned);
97 };
98 
99 /* In profile.c.  */
100 extern void init_branch_prob (void);
101 extern void branch_prob (void);
102 extern void end_branch_prob (void);
103 extern void tree_register_profile_hooks (void);
104 
105 /* In tree-profile.c.  */
106 extern struct profile_hooks tree_profile_hooks;
107 
108 #endif	/* GCC_VALUE_PROF_H */
109 
110