1/* This file contains definitions for the register renamer.
2   Copyright (C) 2011-2015 Free Software Foundation, Inc.
3
4This file is part of GCC.
5
6GCC is free software; you can redistribute it and/or modify it under
7the terms of the GNU General Public License as published by the Free
8Software Foundation; either version 3, or (at your option) any later
9version.
10
11GCC is distributed in the hope that it will be useful, but WITHOUT ANY
12WARRANTY; without even the implied warranty of MERCHANTABILITY or
13FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
14for more details.
15
16You should have received a copy of the GNU General Public License
17along with GCC; see the file COPYING3.  If not see
18<http://www.gnu.org/licenses/>.  */
19
20#ifndef GCC_REGRENAME_H
21#define GCC_REGRENAME_H
22
23/* We keep linked lists of DU_HEAD structures, each of which describes
24   a chain of occurrences of a reg.  */
25struct du_head
26{
27  /* The next chain.  */
28  struct du_head *next_chain;
29  /* The first and last elements of this chain.  */
30  struct du_chain *first, *last;
31  /* Describes the register being tracked.  */
32  unsigned regno;
33  int nregs;
34
35  /* A unique id to be used as an index into the conflicts bitmaps.  */
36  unsigned id;
37  /* A bitmap to record conflicts with other chains.  */
38  bitmap_head conflicts;
39  /* Conflicts with untracked hard registers.  */
40  HARD_REG_SET hard_conflicts;
41
42  /* Nonzero if the chain crosses a call.  */
43  unsigned int need_caller_save_reg:1;
44  /* Nonzero if the register is used in a way that prevents renaming,
45     such as the SET_DEST of a CALL_INSN or an asm operand that used
46     to be a hard register.  */
47  unsigned int cannot_rename:1;
48};
49
50typedef struct du_head *du_head_p;
51
52/* This struct describes a single occurrence of a register.  */
53struct du_chain
54{
55  /* Links to the next occurrence of the register.  */
56  struct du_chain *next_use;
57
58  /* The insn where the register appears.  */
59  rtx_insn *insn;
60  /* The location inside the insn.  */
61  rtx *loc;
62  /* The register class required by the insn at this location.  */
63  ENUM_BITFIELD(reg_class) cl : 16;
64};
65
66/* This struct describes data gathered during regrename_analyze about
67   a single operand of an insn.  */
68struct operand_rr_info
69{
70  /* The number of chains recorded for this operand.  */
71  int n_chains;
72  /* Holds either the chain for the operand itself, or for the registers in
73     a memory operand.  */
74  struct du_chain *chains[MAX_REGS_PER_ADDRESS];
75  struct du_head *heads[MAX_REGS_PER_ADDRESS];
76};
77
78/* A struct to hold a vector of operand_rr_info structures describing the
79   operands of an insn.  */
80struct insn_rr_info
81{
82  operand_rr_info *op_info;
83};
84
85
86extern vec<insn_rr_info> insn_rr;
87
88extern void regrename_init (bool);
89extern void regrename_finish (void);
90extern void regrename_analyze (bitmap);
91extern du_head_p regrename_chain_from_id (unsigned int);
92extern int find_rename_reg (du_head_p, enum reg_class, HARD_REG_SET *, int,
93			    bool);
94extern void regrename_do_replace (du_head_p, int);
95
96#endif
97