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/* Static Single Assignment (SSA) definitions for GNU C-Compiler
Copyright (C) 2000, 2001 Free Software Foundation, Inc.
Written by Jeffrey D. Oldham <oldham@codesourcery.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. */
/* Main SSA routines. */
extern void convert_to_ssa PARAMS ((void));
extern void convert_from_ssa PARAMS ((void));
typedef int (*successor_phi_fn) PARAMS ((rtx, int, int, void *));
extern int for_each_successor_phi PARAMS ((basic_block bb,
successor_phi_fn,
void *));
void compute_dominance_frontiers PARAMS ((sbitmap *frontiers, int *idom));
extern int remove_phi_alternative PARAMS ((rtx, basic_block));
/* Optimizations. */
/* In ssa-dce.c */
extern void ssa_eliminate_dead_code PARAMS ((void));
/* In ssa-ccp.c */
extern void ssa_const_prop PARAMS ((void));
/* SSA definitions and uses. */
/* This flag is set when the CFG is in SSA form. */
extern int in_ssa_form;
/* Element I is the single instruction that sets register I. */
extern varray_type ssa_definition;
/* Element I is an INSN_LIST of instructions that use register I. */
extern varray_type ssa_uses;
/* Specify which hard registers should be converted. */
/* All pseudo-registers (having register number >=
FIRST_PSEUDO_REGISTER) and hard registers satisfying
CONVERT_HARD_REGISTER_TO_SSA_P are converted to SSA form. */
/* Given a hard register number REG_NO, return nonzero if and only if
the register should be converted to SSA. */
#ifndef CONVERT_HARD_REGISTER_TO_SSA_P
#define CONVERT_HARD_REGISTER_TO_SSA_P(REG_NO) (0) /* default of no hard registers */
#endif /* CONVERT_HARD_REGISTER_TO_SSA_P */
/* Given a register number REG_NO, return nonzero if and only if the
register should be converted to SSA. */
#define CONVERT_REGISTER_TO_SSA_P(REG_NO) \
((!HARD_REGISTER_NUM_P (REG_NO)) || \
(CONVERT_HARD_REGISTER_TO_SSA_P (REG_NO)))