lower-subreg.h revision 1.7
1/* Target-dependent costs for lower-subreg.c. 2 Copyright (C) 2012-2018 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