gcc/domwalk.h

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