gcc/value-prof.h

   1 /* Definitions for transformations based on profile information for values.
   2    Copyright (C) 2003 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, 59 Temple Place - Suite 330, Boston, MA
  19 02111-1307, USA.  */
  20
  21 /* Supported histogram types.  */
  22 enum hist_type
  23 {
  24   HIST_TYPE_INTERVAL,   /* Measures histogram of values inside a specified
  25                            interval.  */
  26   HIST_TYPE_POW2,       /* Histogram of power of 2 values.  */
  27   HIST_TYPE_SINGLE_VALUE, /* Tries to identify the value that is (almost)
  28                            always constant.  */
  29   HIST_TYPE_CONST_DELTA /* Tries to identify the (almost) always constant
  30                            difference between two evaluations of a value.  */
  31 };
  32
  33 #define COUNTER_FOR_HIST_TYPE(TYPE) ((int) (TYPE) + GCOV_FIRST_VALUE_COUNTER)
  34 #define HIST_TYPE_FOR_COUNTER(COUNTER) \
  35   ((enum hist_type) ((COUNTER) - GCOV_FIRST_VALUE_COUNTER))
  36
  37 /* The value to measure.  */
  38 struct histogram_value
  39 {
  40   rtx value;            /* The value to profile.  */
  41   enum machine_mode mode; /* And its mode.  */
  42   rtx seq;              /* Insns required to count the profiled value.  */
  43   rtx insn;             /* Insn before that to measure.  */
  44   enum hist_type type;  /* Type of information to measure.  */
  45   unsigned n_counters;  /* Number of required counters.  */
  46   union
  47     {
  48       struct
  49         {
  50           int int_start;        /* First value in interval.  */
  51           int steps;            /* Number of values in it.  */
  52           int may_be_less;      /* May the value be below?  */
  53           int may_be_more;      /* Or above.  */
  54         } intvl;        /* Interval histogram data.  */
  55       struct
  56         {
  57           int may_be_other;     /* If the value may be non-positive or not 2^k.  */
  58         } pow2;         /* Power of 2 histogram data.  */
  59     } hdata;            /* Profiled information specific data.  */
  60 };
  61
  62 extern void find_values_to_profile (unsigned *, struct histogram_value **);
  63 extern void free_profiled_values (unsigned, struct histogram_value *);
  64 extern bool value_profile_transformations (void);