/* Generic dominator tree walker Copyright (C) 2003, 2004 Free Software Foundation, Inc. Contributed by Diego Novillo <dnovillo@redhat.com> This file is part of GCC. GCC is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation; either version 2, or (at your option) any later version. GCC is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details. You should have received a copy of the GNU General Public License along with GCC; see the file COPYING. If not, write to the Free Software Foundation, 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. */ /* This is the main data structure for the dominator walker. It provides the callback hooks as well as a convenient place to hang block local data and pass-global data. */ struct dom_walk_data { /* This is the direction of the dominator tree we want to walk. i.e., if it is set to CDI_DOMINATORS, then we walk the dominator tree, if it is set to CDI_POST_DOMINATORS, then we walk the post dominator tree. */ ENUM_BITFIELD (cdi_direction) dom_direction : 2; /* Nonzero if the statement walker should walk the statements from last to first within a basic block instead of first to last. Note this affects both statement walkers. We haven't yet needed to use the second statement walker for anything, so it's hard to predict if we really need the ability to select their direction independently. */ BOOL_BITFIELD walk_stmts_backward : 1; /* Function to initialize block local data. Note that the dominator walker infrastructure may provide a new fresh, and zero'd block local data structure, or it may re-use an existing block local data structure. If the block local structure has items such as virtual arrays, then that allows your optimizer to re-use those arrays rather than creating new ones. */ void (*initialize_block_local_data) (struct dom_walk_data *, basic_block, bool); /* Function to call before the statement walk occurring before the recursive walk of the dominator children. This typically initializes an block local data and pushes that data onto BLOCK_DATA_STACK. */ void (*before_dom_children_before_stmts) (struct dom_walk_data *, basic_block); /* Function to call to walk statements before the recursive walk of the dominator children. */ void (*before_dom_children_walk_stmts) (struct dom_walk_data *, basic_block, block_stmt_iterator); /* Function to call after the statement walk occurring before the recursive walk of the dominator children. */ void (*before_dom_children_after_stmts) (struct dom_walk_data *, basic_block); /* Function to call before the statement walk occurring after the recursive walk of the dominator children. */ void (*after_dom_children_before_stmts) (struct dom_walk_data *, basic_block); /* Function to call to walk statements after the recursive walk of the dominator children. */ void (*after_dom_children_walk_stmts) (struct dom_walk_data *, basic_block, block_stmt_iterator); /* Function to call after the statement walk occurring after the recursive walk of the dominator children. This typically finalizes any block local data and pops that data from BLOCK_DATA_STACK. */ void (*after_dom_children_after_stmts) (struct dom_walk_data *, basic_block); /* Global data for a walk through the dominator tree. */ void *global_data; /* Stack of any data we need to keep on a per-block basis. If you have no local data, then BLOCK_DATA_STACK will be NULL. */ varray_type block_data_stack; /* Size of the block local data. If this is zero, then it is assumed you have no local data and thus no BLOCK_DATA_STACK as well. */ size_t block_local_data_size; /* From here below are private data. Please do not use this information/data outside domwalk.c. */ /* Stack of available block local structures. */ varray_type free_block_data; }; void walk_dominator_tree (struct dom_walk_data *, basic_block); void init_walk_dominator_tree (struct dom_walk_data *); void fini_walk_dominator_tree (struct dom_walk_data *);