gcc/domwalk.h

   1 /* Generic dominator tree walker
   2    Copyright (C) 2003, 2004, 2005, 2007, 2008, 2012
   3    Free Software Foundation, Inc.
   4    Contributed by Diego Novillo <dnovillo@redhat.com>
   5
   6 This file is part of GCC.
   7
   8 GCC is free software; you can redistribute it and/or modify
   9 it under the terms of the GNU General Public License as published by
  10 the Free Software Foundation; either version 3, or (at your option)
  11 any later version.
  12
  13 GCC is distributed in the hope that it will be useful,
  14 but WITHOUT ANY WARRANTY; without even the implied warranty of
  15 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  16 GNU General Public License for more details.
  17
  18 You should have received a copy of the GNU General Public License
  19 along with GCC; see the file COPYING3.  If not see
  20 <http://www.gnu.org/licenses/>.  */
  21
  22 typedef void *void_p;
  23
  24 /* This is the main data structure for the dominator walker.  It provides
  25    the callback hooks as well as a convenient place to hang block local
  26    data and pass-global data.  */
  27
  28 struct dom_walk_data
  29 {
  30   /* This is the direction of the dominator tree we want to walk.  i.e.,
  31      if it is set to CDI_DOMINATORS, then we walk the dominator tree,
  32      if it is set to CDI_POST_DOMINATORS, then we walk the post
  33      dominator tree.  */
  34   ENUM_BITFIELD (cdi_direction) dom_direction : 2;
  35
  36   /* Function to initialize block local data.
  37
  38      Note that the dominator walker infrastructure may provide a new
  39      fresh, and zero'd block local data structure, or it may re-use an
  40      existing block local data structure.
  41
  42      If the block local structure has items such as virtual arrays, then
  43      that allows your optimizer to re-use those arrays rather than
  44      creating new ones.  */
  45   void (*initialize_block_local_data) (struct dom_walk_data *,
  46                                        basic_block, bool);
  47
  48   /* Function to call before the recursive walk of the dominator children.  */
  49   void (*before_dom_children) (struct dom_walk_data *, basic_block);
  50
  51   /* Function to call after the recursive walk of the dominator children.  */
  52   void (*after_dom_children) (struct dom_walk_data *, basic_block);
  53
  54   /* Global data for a walk through the dominator tree.  */
  55   void *global_data;
  56
  57   /* Stack of any data we need to keep on a per-block basis.
  58
  59      If you have no local data, then BLOCK_DATA_STACK will be NULL.  */
  60   vec<void_p> block_data_stack;
  61
  62   /* Size of the block local data.   If this is zero, then it is assumed
  63      you have no local data and thus no BLOCK_DATA_STACK as well.  */
  64   size_t block_local_data_size;
  65
  66   /* From here below are private data.  Please do not use this
  67      information/data outside domwalk.c.  */
  68
  69   /* Stack of available block local structures.  */
  70   vec<void_p> free_block_data;
  71 };
  72
  73 void walk_dominator_tree (struct dom_walk_data *, basic_block);
  74 void init_walk_dominator_tree (struct dom_walk_data *);
  75 void fini_walk_dominator_tree (struct dom_walk_data *);