1 /* Target-dependent costs for lower-subreg.c.
2    Copyright (C) 2012-2018 Free Software Foundation, Inc.
3 
4 This file is part of GCC.
5 
6 GCC is free software; you can redistribute it and/or modify it under
7 the terms of the GNU General Public License as published by the Free
8 Software Foundation; either version 3, or (at your option) any later
9 version.
10 
11 GCC is distributed in the hope that it will be useful, but WITHOUT ANY
12 WARRANTY; without even the implied warranty of MERCHANTABILITY or
13 FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
14 for more details.
15 
16 You should have received a copy of the GNU General Public License
17 along 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.  */
24 struct 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.  */
44 struct 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 
53 extern struct target_lower_subreg default_target_lower_subreg;
54 #if SWITCHABLE_TARGET
55 extern 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