1 /* Static Single Assignment (SSA) definitions for GNU C-Compiler
2 Copyright (C) 2000, 2001 Free Software Foundation, Inc.
3 Written by Jeffrey D. Oldham <oldham@codesourcery.com>.
5 This file is part of GCC.
7 GCC is free software; you can redistribute it and/or modify it under
8 the terms of the GNU General Public License as published by the Free
9 Software Foundation; either version 2, or (at your option) any later
12 GCC is distributed in the hope that it will be useful, but WITHOUT ANY
13 WARRANTY; without even the implied warranty of MERCHANTABILITY or
14 FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
17 You should have received a copy of the GNU General Public License
18 along with GCC; see the file COPYING. If not, write to the Free
19 Software Foundation, 59 Temple Place - Suite 330, Boston, MA
23 /* Main SSA routines. */
24 extern void convert_to_ssa
PARAMS ((void));
25 extern void convert_from_ssa
PARAMS ((void));
26 typedef int (*successor_phi_fn
) PARAMS ((rtx
, int, int, void *));
27 extern int for_each_successor_phi
PARAMS ((basic_block bb
,
30 void compute_dominance_frontiers
PARAMS ((sbitmap
*frontiers
,
31 dominance_info idom
));
32 extern int remove_phi_alternative
PARAMS ((rtx
, basic_block
));
37 extern void ssa_eliminate_dead_code
PARAMS ((void));
40 extern void ssa_const_prop
PARAMS ((void));
43 /* SSA definitions and uses. */
44 /* This flag is set when the CFG is in SSA form. */
45 extern int in_ssa_form
;
47 /* Element I is the single instruction that sets register I. */
48 extern GTY(()) varray_type ssa_definition
;
50 /* Element I is an INSN_LIST of instructions that use register I. */
51 extern varray_type ssa_uses
;
54 /* Specify which hard registers should be converted. */
56 /* All pseudo-registers (having register number >=
57 FIRST_PSEUDO_REGISTER) and hard registers satisfying
58 CONVERT_HARD_REGISTER_TO_SSA_P are converted to SSA form. */
60 /* Given a hard register number REG_NO, return nonzero if and only if
61 the register should be converted to SSA. */
63 #ifndef CONVERT_HARD_REGISTER_TO_SSA_P
64 #define CONVERT_HARD_REGISTER_TO_SSA_P(REG_NO) (0) /* default of no hard registers */
65 #endif /* CONVERT_HARD_REGISTER_TO_SSA_P */
67 /* Given a register number REG_NO, return nonzero if and only if the
68 register should be converted to SSA. */
70 #define CONVERT_REGISTER_TO_SSA_P(REG_NO) \
71 ((!HARD_REGISTER_NUM_P (REG_NO)) || \
72 (CONVERT_HARD_REGISTER_TO_SSA_P (REG_NO)))