1/* Target-dependent costs for lower-subreg.c.
2 Copyright (C) 2012-2017 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 LOWER_SUBREG_H
21#define LOWER_SUBREG_H 1
22
23/* Information about whether, and where, lower-subreg should be applied. */
24struct lower_subreg_choices {
25 /* A boolean vector for move splitting that is indexed by mode and is
26 true for each mode that is to have its copies split. */
27 bool move_modes_to_split[MAX_MACHINE_MODE];
28
29 /* True if zero-extensions from word_mode to twice_word_mode should
30 be split. */
31 bool splitting_zext;
32
33 /* Index X is true if twice_word_mode shifts by X + BITS_PER_WORD
34 should be split. */
35 bool splitting_ashift[MAX_BITS_PER_WORD];
36 bool splitting_lshiftrt[MAX_BITS_PER_WORD];
37 bool splitting_ashiftrt[MAX_BITS_PER_WORD];
38
39 /* True if there is at least one mode that is worth splitting. */
40 bool something_to_do;
41};
42
43/* Target-specific information for the subreg lowering pass. */
44struct target_lower_subreg {
45 /* An integer mode that is twice as wide as word_mode. */
46 scalar_int_mode_pod x_twice_word_mode;
47
48 /* What we have decided to do when optimizing for size (index 0)
49 and speed (index 1). */
50 struct lower_subreg_choices x_choices[2];
51};
52
53extern struct target_lower_subreg default_target_lower_subreg;
54#if SWITCHABLE_TARGET
55extern struct target_lower_subreg *this_target_lower_subreg;
56#else
57#define this_target_lower_subreg (&default_target_lower_subreg)
58#endif
59
60#endif
61