CbC/CbC_gcc: gcc/compare-elim.c annotate

annotate gcc/compare-elim.c @ 131:84e7813d76e9

gcc-8.2

author	mir3636
date	Thu, 25 Oct 2018 07:37:49 +0900
parents	04ced10e8804
children	1830386684a0

rev	line source
68 561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	1 /* Post-reload compare elimination.
131 84e7813d76e9 gcc-8.2 mir3636 parents: 111 diff changeset	2 Copyright (C) 2010-2018 Free Software Foundation, Inc.
68 561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	3
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	4 This file is part of GCC.
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	5
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	6 GCC is free software; you can redistribute it and/or modify it under
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	7 the terms of the GNU General Public License as published by the Free
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	8 Software Foundation; either version 3, or (at your option) any later
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	9 version.
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	10
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	11 GCC is distributed in the hope that it will be useful, but WITHOUT ANY
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	12 WARRANTY; without even the implied warranty of MERCHANTABILITY or
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	13 FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	14 for more details.
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	15
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	16 You should have received a copy of the GNU General Public License
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	17 along with GCC; see the file COPYING3. If not see
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	18 <http://www.gnu.org/licenses/>. */
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	19
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	20 /* There is a set of targets whose general-purpose move or addition
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	21 instructions clobber the flags. These targets cannot split their
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	22 CBRANCH/CSTORE etc patterns before reload is complete, lest reload
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	23 itself insert these instructions in between the flags setter and user.
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	24 Because these targets cannot split the compare from the use, they
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	25 cannot make use of the comparison elimination offered by the combine pass.
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	26
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	27 This is a small pass intended to provide comparison elimination similar to
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	28 what is available via NOTICE_UPDATE_CC for cc0 targets. This should help
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	29 encourage cc0 targets to convert to an explicit post-reload representation
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	30 of the flags.
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	31
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	32 This pass assumes:
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	33
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	34 (0) CBRANCH/CSTORE etc have been split in pass_split_after_reload.
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	35
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	36 (1) All comparison patterns are represented as
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	37
111 04ced10e8804 gcc 7 kono parents: 68 diff changeset	38 [(set (reg:CC) (compare:CC (reg) (reg_or_immediate)))]
68 561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	39
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	40 (2) All insn patterns that modify the flags are represented as
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	41
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	42 [(set (reg) (operation)
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	43 (clobber (reg:CC))]
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	44
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	45 (3) If an insn of form (2) can usefully set the flags, there is
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	46 another pattern of the form
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	47
111 04ced10e8804 gcc 7 kono parents: 68 diff changeset	48 [(set (reg:CCM) (compare:CCM (operation) (immediate)))
04ced10e8804 gcc 7 kono parents: 68 diff changeset	49 (set (reg) (operation)]
04ced10e8804 gcc 7 kono parents: 68 diff changeset	50
68 561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	51 The mode CCM will be chosen as if by SELECT_CC_MODE.
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	52
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	53 Note that unlike NOTICE_UPDATE_CC, we do not handle memory operands.
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	54 This could be handled as a future enhancement.
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	55 */
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	56
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	57 #include "config.h"
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	58 #include "system.h"
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	59 #include "coretypes.h"
111 04ced10e8804 gcc 7 kono parents: 68 diff changeset	60 #include "backend.h"
04ced10e8804 gcc 7 kono parents: 68 diff changeset	61 #include "target.h"
68 561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	62 #include "rtl.h"
111 04ced10e8804 gcc 7 kono parents: 68 diff changeset	63 #include "df.h"
04ced10e8804 gcc 7 kono parents: 68 diff changeset	64 #include "memmodel.h"
68 561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	65 #include "tm_p.h"
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	66 #include "insn-config.h"
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	67 #include "recog.h"
111 04ced10e8804 gcc 7 kono parents: 68 diff changeset	68 #include "emit-rtl.h"
04ced10e8804 gcc 7 kono parents: 68 diff changeset	69 #include "cfgrtl.h"
68 561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	70 #include "tree-pass.h"
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	71 #include "domwalk.h"
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	72
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	73
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	74 /* These structures describe a comparison and how it is used. */
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	75
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	76 /* The choice of maximum 3 uses comes from wanting to eliminate the two
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	77 duplicate compares from a three-way branch on the sign of a value.
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	78 This is also sufficient to eliminate the duplicate compare against the
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	79 high-part of a double-word comparison. */
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	80 #define MAX_CMP_USE 3
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	81
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	82 struct comparison_use
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	83 {
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	84 /* The instruction in which the result of the compare is used. */
111 04ced10e8804 gcc 7 kono parents: 68 diff changeset	85 rtx_insn *insn;
68 561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	86 /* The location of the flags register within the use. */
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	87 rtx *loc;
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	88 /* The comparison code applied against the flags register. */
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	89 enum rtx_code code;
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	90 };
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	91
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	92 struct comparison
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	93 {
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	94 /* The comparison instruction. */
111 04ced10e8804 gcc 7 kono parents: 68 diff changeset	95 rtx_insn *insn;
68 561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	96
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	97 /* The insn prior to the comparison insn that clobbers the flags. */
111 04ced10e8804 gcc 7 kono parents: 68 diff changeset	98 rtx_insn *prev_clobber;
68 561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	99
131 84e7813d76e9 gcc-8.2 mir3636 parents: 111 diff changeset	100 /* The insn prior to the comparison insn that sets in_a REG. */
84e7813d76e9 gcc-8.2 mir3636 parents: 111 diff changeset	101 rtx_insn *in_a_setter;
84e7813d76e9 gcc-8.2 mir3636 parents: 111 diff changeset	102
68 561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	103 /* The two values being compared. These will be either REGs or
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	104 constants. */
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	105 rtx in_a, in_b;
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	106
111 04ced10e8804 gcc 7 kono parents: 68 diff changeset	107 /* The REG_EH_REGION of the comparison. */
04ced10e8804 gcc 7 kono parents: 68 diff changeset	108 rtx eh_note;
04ced10e8804 gcc 7 kono parents: 68 diff changeset	109
68 561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	110 /* Information about how this comparison is used. */
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	111 struct comparison_use uses[MAX_CMP_USE];
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	112
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	113 /* The original CC_MODE for this comparison. */
111 04ced10e8804 gcc 7 kono parents: 68 diff changeset	114 machine_mode orig_mode;
68 561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	115
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	116 /* The number of uses identified for this comparison. */
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	117 unsigned short n_uses;
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	118
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	119 /* True if not all uses of this comparison have been identified.
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	120 This can happen either for overflowing the array above, or if
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	121 the flags register is used in some unusual context. */
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	122 bool missing_uses;
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	123
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	124 /* True if its inputs are still valid at the end of the block. */
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	125 bool inputs_valid;
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	126 };
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	127
111 04ced10e8804 gcc 7 kono parents: 68 diff changeset	128 static vec<comparison *> all_compares;
68 561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	129
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	130 /* Look for a "conforming" comparison, as defined above. If valid, return
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	131 the rtx for the COMPARE itself. */
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	132
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	133 static rtx
111 04ced10e8804 gcc 7 kono parents: 68 diff changeset	134 conforming_compare (rtx_insn *insn)
68 561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	135 {
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	136 rtx set, src, dest;
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	137
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	138 set = single_set (insn);
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	139 if (set == NULL)
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	140 return NULL;
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	141
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	142 src = SET_SRC (set);
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	143 if (GET_CODE (src) != COMPARE)
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	144 return NULL;
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	145
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	146 dest = SET_DEST (set);
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	147 if (!REG_P (dest) \|\| REGNO (dest) != targetm.flags_regnum)
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	148 return NULL;
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	149
111 04ced10e8804 gcc 7 kono parents: 68 diff changeset	150 if (!REG_P (XEXP (src, 0)))
04ced10e8804 gcc 7 kono parents: 68 diff changeset	151 return NULL;
04ced10e8804 gcc 7 kono parents: 68 diff changeset	152
04ced10e8804 gcc 7 kono parents: 68 diff changeset	153 if (CONSTANT_P (XEXP (src, 1)) \|\| REG_P (XEXP (src, 1)))
68 561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	154 return src;
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	155
111 04ced10e8804 gcc 7 kono parents: 68 diff changeset	156 if (GET_CODE (XEXP (src, 1)) == UNSPEC)
04ced10e8804 gcc 7 kono parents: 68 diff changeset	157 {
04ced10e8804 gcc 7 kono parents: 68 diff changeset	158 for (int i = 0; i < XVECLEN (XEXP (src, 1), 0); i++)
04ced10e8804 gcc 7 kono parents: 68 diff changeset	159 if (!REG_P (XVECEXP (XEXP (src, 1), 0, i)))
04ced10e8804 gcc 7 kono parents: 68 diff changeset	160 return NULL;
04ced10e8804 gcc 7 kono parents: 68 diff changeset	161 return src;
04ced10e8804 gcc 7 kono parents: 68 diff changeset	162 }
04ced10e8804 gcc 7 kono parents: 68 diff changeset	163
68 561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	164 return NULL;
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	165 }
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	166
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	167 /* Look for a pattern of the "correct" form for an insn with a flags clobber
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	168 for which we may be able to eliminate a compare later. We're not looking
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	169 to validate any inputs at this time, merely see that the basic shape is
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	170 correct. The term "arithmetic" may be somewhat misleading... */
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	171
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	172 static bool
111 04ced10e8804 gcc 7 kono parents: 68 diff changeset	173 arithmetic_flags_clobber_p (rtx_insn *insn)
68 561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	174 {
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	175 rtx pat, x;
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	176
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	177 if (!NONJUMP_INSN_P (insn))
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	178 return false;
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	179 pat = PATTERN (insn);
111 04ced10e8804 gcc 7 kono parents: 68 diff changeset	180 if (asm_noperands (pat) >= 0)
68 561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	181 return false;
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	182
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	183 if (GET_CODE (pat) == PARALLEL && XVECLEN (pat, 0) == 2)
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	184 {
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	185 x = XVECEXP (pat, 0, 0);
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	186 if (GET_CODE (x) != SET)
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	187 return false;
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	188 x = SET_DEST (x);
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	189 if (!REG_P (x))
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	190 return false;
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	191
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	192 x = XVECEXP (pat, 0, 1);
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	193 if (GET_CODE (x) == CLOBBER)
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	194 {
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	195 x = XEXP (x, 0);
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	196 if (REG_P (x) && REGNO (x) == targetm.flags_regnum)
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	197 return true;
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	198 }
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	199 }
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	200
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	201 return false;
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	202 }
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	203
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	204 /* Look for uses of FLAGS in INSN. If we find one we can analyze, record
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	205 it in CMP; otherwise indicate that we've missed a use. */
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	206
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	207 static void
111 04ced10e8804 gcc 7 kono parents: 68 diff changeset	208 find_flags_uses_in_insn (struct comparison cmp, rtx_insn insn)
68 561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	209 {
111 04ced10e8804 gcc 7 kono parents: 68 diff changeset	210 df_ref use;
68 561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	211
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	212 /* If we've already lost track of uses, don't bother collecting more. */
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	213 if (cmp->missing_uses)
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	214 return;
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	215
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	216 /* Find a USE of the flags register. */
111 04ced10e8804 gcc 7 kono parents: 68 diff changeset	217 FOR_EACH_INSN_USE (use, insn)
68 561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	218 if (DF_REF_REGNO (use) == targetm.flags_regnum)
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	219 {
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	220 rtx x, *loc;
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	221
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	222 /* If this is an unusual use, quit. */
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	223 if (DF_REF_TYPE (use) != DF_REF_REG_USE)
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	224 goto fail;
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	225
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	226 /* If we've run out of slots to record uses, quit. */
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	227 if (cmp->n_uses == MAX_CMP_USE)
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	228 goto fail;
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	229
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	230 /* Unfortunately the location of the flags register, while present
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	231 in the reference structure, doesn't help. We need to find the
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	232 comparison code that is outer to the actual flags use. */
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	233 loc = DF_REF_LOC (use);
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	234 x = PATTERN (insn);
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	235 if (GET_CODE (x) == PARALLEL)
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	236 x = XVECEXP (x, 0, 0);
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	237 x = SET_SRC (x);
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	238 if (GET_CODE (x) == IF_THEN_ELSE)
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	239 x = XEXP (x, 0);
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	240 if (COMPARISON_P (x)
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	241 && loc == &XEXP (x, 0)
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	242 && XEXP (x, 1) == const0_rtx)
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	243 {
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	244 /* We've found a use of the flags that we understand. */
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	245 struct comparison_use *cuse = &cmp->uses[cmp->n_uses++];
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	246 cuse->insn = insn;
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	247 cuse->loc = loc;
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	248 cuse->code = GET_CODE (x);
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	249 }
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	250 else
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	251 goto fail;
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	252 }
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	253 return;
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	254
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	255 fail:
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	256 /* We failed to recognize this use of the flags register. */
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	257 cmp->missing_uses = true;
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	258 }
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	259
111 04ced10e8804 gcc 7 kono parents: 68 diff changeset	260 class find_comparison_dom_walker : public dom_walker
04ced10e8804 gcc 7 kono parents: 68 diff changeset	261 {
04ced10e8804 gcc 7 kono parents: 68 diff changeset	262 public:
04ced10e8804 gcc 7 kono parents: 68 diff changeset	263 find_comparison_dom_walker (cdi_direction direction)
04ced10e8804 gcc 7 kono parents: 68 diff changeset	264 : dom_walker (direction) {}
04ced10e8804 gcc 7 kono parents: 68 diff changeset	265
04ced10e8804 gcc 7 kono parents: 68 diff changeset	266 virtual edge before_dom_children (basic_block);
04ced10e8804 gcc 7 kono parents: 68 diff changeset	267 };
04ced10e8804 gcc 7 kono parents: 68 diff changeset	268
04ced10e8804 gcc 7 kono parents: 68 diff changeset	269 /* Return true if conforming COMPARE with EH_NOTE is redundant with comparison
04ced10e8804 gcc 7 kono parents: 68 diff changeset	270 CMP and can thus be eliminated. */
04ced10e8804 gcc 7 kono parents: 68 diff changeset	271
04ced10e8804 gcc 7 kono parents: 68 diff changeset	272 static bool
04ced10e8804 gcc 7 kono parents: 68 diff changeset	273 can_eliminate_compare (rtx compare, rtx eh_note, struct comparison *cmp)
04ced10e8804 gcc 7 kono parents: 68 diff changeset	274 {
04ced10e8804 gcc 7 kono parents: 68 diff changeset	275 /* Take care that it's in the same EH region. */
04ced10e8804 gcc 7 kono parents: 68 diff changeset	276 if (cfun->can_throw_non_call_exceptions
04ced10e8804 gcc 7 kono parents: 68 diff changeset	277 && !rtx_equal_p (eh_note, cmp->eh_note))
04ced10e8804 gcc 7 kono parents: 68 diff changeset	278 return false;
04ced10e8804 gcc 7 kono parents: 68 diff changeset	279
04ced10e8804 gcc 7 kono parents: 68 diff changeset	280 /* Make sure the compare is redundant with the previous. */
04ced10e8804 gcc 7 kono parents: 68 diff changeset	281 if (!rtx_equal_p (XEXP (compare, 0), cmp->in_a)
04ced10e8804 gcc 7 kono parents: 68 diff changeset	282 \|\| !rtx_equal_p (XEXP (compare, 1), cmp->in_b))
04ced10e8804 gcc 7 kono parents: 68 diff changeset	283 return false;
04ced10e8804 gcc 7 kono parents: 68 diff changeset	284
04ced10e8804 gcc 7 kono parents: 68 diff changeset	285 /* New mode must be compatible with the previous compare mode. */
04ced10e8804 gcc 7 kono parents: 68 diff changeset	286 machine_mode new_mode
04ced10e8804 gcc 7 kono parents: 68 diff changeset	287 = targetm.cc_modes_compatible (GET_MODE (compare), cmp->orig_mode);
04ced10e8804 gcc 7 kono parents: 68 diff changeset	288
04ced10e8804 gcc 7 kono parents: 68 diff changeset	289 if (new_mode == VOIDmode)
04ced10e8804 gcc 7 kono parents: 68 diff changeset	290 return false;
04ced10e8804 gcc 7 kono parents: 68 diff changeset	291
04ced10e8804 gcc 7 kono parents: 68 diff changeset	292 if (cmp->orig_mode != new_mode)
04ced10e8804 gcc 7 kono parents: 68 diff changeset	293 {
04ced10e8804 gcc 7 kono parents: 68 diff changeset	294 /* Generate new comparison for substitution. */
04ced10e8804 gcc 7 kono parents: 68 diff changeset	295 rtx flags = gen_rtx_REG (new_mode, targetm.flags_regnum);
04ced10e8804 gcc 7 kono parents: 68 diff changeset	296 rtx x = gen_rtx_COMPARE (new_mode, cmp->in_a, cmp->in_b);
04ced10e8804 gcc 7 kono parents: 68 diff changeset	297 x = gen_rtx_SET (flags, x);
04ced10e8804 gcc 7 kono parents: 68 diff changeset	298
04ced10e8804 gcc 7 kono parents: 68 diff changeset	299 if (!validate_change (cmp->insn, &PATTERN (cmp->insn), x, false))
04ced10e8804 gcc 7 kono parents: 68 diff changeset	300 return false;
04ced10e8804 gcc 7 kono parents: 68 diff changeset	301
04ced10e8804 gcc 7 kono parents: 68 diff changeset	302 cmp->orig_mode = new_mode;
04ced10e8804 gcc 7 kono parents: 68 diff changeset	303 }
04ced10e8804 gcc 7 kono parents: 68 diff changeset	304
04ced10e8804 gcc 7 kono parents: 68 diff changeset	305 return true;
04ced10e8804 gcc 7 kono parents: 68 diff changeset	306 }
04ced10e8804 gcc 7 kono parents: 68 diff changeset	307
68 561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	308 /* Identify comparison instructions within BB. If the flags from the last
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	309 compare in the BB is live at the end of the block, install the compare
111 04ced10e8804 gcc 7 kono parents: 68 diff changeset	310 in BB->AUX. Called via dom_walker.walk (). */
68 561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	311
111 04ced10e8804 gcc 7 kono parents: 68 diff changeset	312 edge
04ced10e8804 gcc 7 kono parents: 68 diff changeset	313 find_comparison_dom_walker::before_dom_children (basic_block bb)
68 561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	314 {
131 84e7813d76e9 gcc-8.2 mir3636 parents: 111 diff changeset	315 rtx_insn insn, next;
111 04ced10e8804 gcc 7 kono parents: 68 diff changeset	316 bool need_purge = false;
131 84e7813d76e9 gcc-8.2 mir3636 parents: 111 diff changeset	317 rtx_insn *last_setter[FIRST_PSEUDO_REGISTER];
68 561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	318
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	319 /* The last comparison that was made. Will be reset to NULL
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	320 once the flags are clobbered. */
131 84e7813d76e9 gcc-8.2 mir3636 parents: 111 diff changeset	321 struct comparison *last_cmp = NULL;
68 561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	322
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	323 /* True iff the last comparison has not been clobbered, nor
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	324 have its inputs. Used to eliminate duplicate compares. */
131 84e7813d76e9 gcc-8.2 mir3636 parents: 111 diff changeset	325 bool last_cmp_valid = false;
68 561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	326
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	327 /* The last insn that clobbered the flags, if that insn is of
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	328 a form that may be valid for eliminating a following compare.
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	329 To be reset to NULL once the flags are set otherwise. */
131 84e7813d76e9 gcc-8.2 mir3636 parents: 111 diff changeset	330 rtx_insn *last_clobber = NULL;
68 561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	331
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	332 /* Propagate the last live comparison throughout the extended basic block. */
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	333 if (single_pred_p (bb))
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	334 {
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	335 last_cmp = (struct comparison *) single_pred (bb)->aux;
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	336 if (last_cmp)
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	337 last_cmp_valid = last_cmp->inputs_valid;
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	338 }
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	339
131 84e7813d76e9 gcc-8.2 mir3636 parents: 111 diff changeset	340 memset (last_setter, 0, sizeof (last_setter));
68 561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	341 for (insn = BB_HEAD (bb); insn; insn = next)
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	342 {
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	343 rtx src;
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	344
111 04ced10e8804 gcc 7 kono parents: 68 diff changeset	345 next = (insn == BB_END (bb) ? NULL : NEXT_INSN (insn));
68 561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	346 if (!NONDEBUG_INSN_P (insn))
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	347 continue;
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	348
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	349 src = conforming_compare (insn);
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	350 if (src)
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	351 {
111 04ced10e8804 gcc 7 kono parents: 68 diff changeset	352 rtx eh_note = NULL;
04ced10e8804 gcc 7 kono parents: 68 diff changeset	353
04ced10e8804 gcc 7 kono parents: 68 diff changeset	354 if (cfun->can_throw_non_call_exceptions)
04ced10e8804 gcc 7 kono parents: 68 diff changeset	355 eh_note = find_reg_note (insn, REG_EH_REGION, NULL);
04ced10e8804 gcc 7 kono parents: 68 diff changeset	356
04ced10e8804 gcc 7 kono parents: 68 diff changeset	357 if (last_cmp_valid && can_eliminate_compare (src, eh_note, last_cmp))
68 561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	358 {
111 04ced10e8804 gcc 7 kono parents: 68 diff changeset	359 if (eh_note)
04ced10e8804 gcc 7 kono parents: 68 diff changeset	360 need_purge = true;
68 561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	361 delete_insn (insn);
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	362 continue;
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	363 }
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	364
111 04ced10e8804 gcc 7 kono parents: 68 diff changeset	365 last_cmp = XCNEW (struct comparison);
68 561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	366 last_cmp->insn = insn;
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	367 last_cmp->prev_clobber = last_clobber;
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	368 last_cmp->in_a = XEXP (src, 0);
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	369 last_cmp->in_b = XEXP (src, 1);
111 04ced10e8804 gcc 7 kono parents: 68 diff changeset	370 last_cmp->eh_note = eh_note;
04ced10e8804 gcc 7 kono parents: 68 diff changeset	371 last_cmp->orig_mode = GET_MODE (src);
131 84e7813d76e9 gcc-8.2 mir3636 parents: 111 diff changeset	372 if (last_cmp->in_b == const0_rtx
84e7813d76e9 gcc-8.2 mir3636 parents: 111 diff changeset	373 && last_setter[REGNO (last_cmp->in_a)])
84e7813d76e9 gcc-8.2 mir3636 parents: 111 diff changeset	374 {
84e7813d76e9 gcc-8.2 mir3636 parents: 111 diff changeset	375 rtx set = single_set (last_setter[REGNO (last_cmp->in_a)]);
84e7813d76e9 gcc-8.2 mir3636 parents: 111 diff changeset	376 if (set && rtx_equal_p (SET_DEST (set), last_cmp->in_a))
84e7813d76e9 gcc-8.2 mir3636 parents: 111 diff changeset	377 last_cmp->in_a_setter = last_setter[REGNO (last_cmp->in_a)];
84e7813d76e9 gcc-8.2 mir3636 parents: 111 diff changeset	378 }
111 04ced10e8804 gcc 7 kono parents: 68 diff changeset	379 all_compares.safe_push (last_cmp);
68 561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	380
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	381 /* It's unusual, but be prepared for comparison patterns that
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	382 also clobber an input, or perhaps a scratch. */
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	383 last_clobber = NULL;
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	384 last_cmp_valid = true;
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	385 }
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	386
111 04ced10e8804 gcc 7 kono parents: 68 diff changeset	387 else
68 561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	388 {
111 04ced10e8804 gcc 7 kono parents: 68 diff changeset	389 /* Notice if this instruction uses the flags register. */
04ced10e8804 gcc 7 kono parents: 68 diff changeset	390 if (last_cmp)
04ced10e8804 gcc 7 kono parents: 68 diff changeset	391 find_flags_uses_in_insn (last_cmp, insn);
68 561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	392
111 04ced10e8804 gcc 7 kono parents: 68 diff changeset	393 /* Notice if this instruction kills the flags register. */
131 84e7813d76e9 gcc-8.2 mir3636 parents: 111 diff changeset	394 df_ref def;
84e7813d76e9 gcc-8.2 mir3636 parents: 111 diff changeset	395 FOR_EACH_INSN_DEF (def, insn)
84e7813d76e9 gcc-8.2 mir3636 parents: 111 diff changeset	396 if (DF_REF_REGNO (def) == targetm.flags_regnum)
84e7813d76e9 gcc-8.2 mir3636 parents: 111 diff changeset	397 {
84e7813d76e9 gcc-8.2 mir3636 parents: 111 diff changeset	398 /* See if this insn could be the "clobber" that eliminates
84e7813d76e9 gcc-8.2 mir3636 parents: 111 diff changeset	399 a future comparison. */
84e7813d76e9 gcc-8.2 mir3636 parents: 111 diff changeset	400 last_clobber = (arithmetic_flags_clobber_p (insn)
84e7813d76e9 gcc-8.2 mir3636 parents: 111 diff changeset	401 ? insn : NULL);
111 04ced10e8804 gcc 7 kono parents: 68 diff changeset	402
131 84e7813d76e9 gcc-8.2 mir3636 parents: 111 diff changeset	403 /* In either case, the previous compare is no longer valid. */
84e7813d76e9 gcc-8.2 mir3636 parents: 111 diff changeset	404 last_cmp = NULL;
84e7813d76e9 gcc-8.2 mir3636 parents: 111 diff changeset	405 last_cmp_valid = false;
84e7813d76e9 gcc-8.2 mir3636 parents: 111 diff changeset	406 break;
84e7813d76e9 gcc-8.2 mir3636 parents: 111 diff changeset	407 }
68 561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	408 }
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	409
131 84e7813d76e9 gcc-8.2 mir3636 parents: 111 diff changeset	410 /* Notice if any of the inputs to the comparison have changed
84e7813d76e9 gcc-8.2 mir3636 parents: 111 diff changeset	411 and remember last insn that sets each register. */
84e7813d76e9 gcc-8.2 mir3636 parents: 111 diff changeset	412 df_ref def;
84e7813d76e9 gcc-8.2 mir3636 parents: 111 diff changeset	413 FOR_EACH_INSN_DEF (def, insn)
84e7813d76e9 gcc-8.2 mir3636 parents: 111 diff changeset	414 {
84e7813d76e9 gcc-8.2 mir3636 parents: 111 diff changeset	415 if (last_cmp_valid
84e7813d76e9 gcc-8.2 mir3636 parents: 111 diff changeset	416 && (DF_REF_REGNO (def) == REGNO (last_cmp->in_a)
84e7813d76e9 gcc-8.2 mir3636 parents: 111 diff changeset	417 \|\| (REG_P (last_cmp->in_b)
84e7813d76e9 gcc-8.2 mir3636 parents: 111 diff changeset	418 && DF_REF_REGNO (def) == REGNO (last_cmp->in_b))))
84e7813d76e9 gcc-8.2 mir3636 parents: 111 diff changeset	419 last_cmp_valid = false;
84e7813d76e9 gcc-8.2 mir3636 parents: 111 diff changeset	420 last_setter[DF_REF_REGNO (def)] = insn;
84e7813d76e9 gcc-8.2 mir3636 parents: 111 diff changeset	421 }
68 561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	422 }
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	423
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	424 /* Remember the live comparison for subsequent members of
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	425 the extended basic block. */
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	426 if (last_cmp)
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	427 {
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	428 bb->aux = last_cmp;
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	429 last_cmp->inputs_valid = last_cmp_valid;
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	430
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	431 /* Look to see if the flags register is live outgoing here, and
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	432 incoming to any successor not part of the extended basic block. */
111 04ced10e8804 gcc 7 kono parents: 68 diff changeset	433 if (bitmap_bit_p (df_get_live_out (bb), targetm.flags_regnum))
68 561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	434 {
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	435 edge e;
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	436 edge_iterator ei;
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	437
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	438 FOR_EACH_EDGE (e, ei, bb->succs)
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	439 {
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	440 basic_block dest = e->dest;
111 04ced10e8804 gcc 7 kono parents: 68 diff changeset	441 if (bitmap_bit_p (df_get_live_in (bb), targetm.flags_regnum)
68 561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	442 && !single_pred_p (dest))
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	443 {
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	444 last_cmp->missing_uses = true;
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	445 break;
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	446 }
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	447 }
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	448 }
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	449 }
111 04ced10e8804 gcc 7 kono parents: 68 diff changeset	450
04ced10e8804 gcc 7 kono parents: 68 diff changeset	451 /* If we deleted a compare with a REG_EH_REGION note, we may need to
04ced10e8804 gcc 7 kono parents: 68 diff changeset	452 remove EH edges. */
04ced10e8804 gcc 7 kono parents: 68 diff changeset	453 if (need_purge)
04ced10e8804 gcc 7 kono parents: 68 diff changeset	454 purge_dead_edges (bb);
04ced10e8804 gcc 7 kono parents: 68 diff changeset	455
04ced10e8804 gcc 7 kono parents: 68 diff changeset	456 return NULL;
68 561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	457 }
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	458
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	459 /* Find all comparisons in the function. */
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	460
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	461 static void
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	462 find_comparisons (void)
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	463 {
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	464 calculate_dominance_info (CDI_DOMINATORS);
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	465
111 04ced10e8804 gcc 7 kono parents: 68 diff changeset	466 find_comparison_dom_walker (CDI_DOMINATORS)
04ced10e8804 gcc 7 kono parents: 68 diff changeset	467 .walk (cfun->cfg->x_entry_block_ptr);
68 561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	468
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	469 clear_aux_for_blocks ();
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	470 free_dominance_info (CDI_DOMINATORS);
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	471 }
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	472
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	473 /* Select an alternate CC_MODE for a comparison insn comparing A and B.
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	474 Note that inputs are almost certainly different than the IN_A and IN_B
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	475 stored in CMP -- we're called while attempting to eliminate the compare
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	476 after all. Return the new FLAGS rtx if successful, else return NULL.
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	477 Note that this function may start a change group. */
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	478
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	479 static rtx
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	480 maybe_select_cc_mode (struct comparison *cmp, rtx a ATTRIBUTE_UNUSED,
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	481 rtx b ATTRIBUTE_UNUSED)
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	482 {
111 04ced10e8804 gcc 7 kono parents: 68 diff changeset	483 machine_mode sel_mode;
68 561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	484 const int n = cmp->n_uses;
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	485 rtx flags = NULL;
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	486
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	487 #ifndef SELECT_CC_MODE
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	488 /* Minimize code differences when this target macro is undefined. */
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	489 return NULL;
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	490 #define SELECT_CC_MODE(A,B,C) (gcc_unreachable (), VOIDmode)
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	491 #endif
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	492
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	493 /* If we don't have access to all of the uses, we can't validate. */
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	494 if (cmp->missing_uses \|\| n == 0)
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	495 return NULL;
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	496
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	497 /* Find a new mode that works for all of the uses. Special case the
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	498 common case of exactly one use. */
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	499 if (n == 1)
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	500 {
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	501 sel_mode = SELECT_CC_MODE (cmp->uses[0].code, a, b);
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	502 if (sel_mode != cmp->orig_mode)
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	503 {
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	504 flags = gen_rtx_REG (sel_mode, targetm.flags_regnum);
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	505 validate_change (cmp->uses[0].insn, cmp->uses[0].loc, flags, true);
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	506 }
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	507 }
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	508 else
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	509 {
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	510 int i;
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	511
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	512 sel_mode = SELECT_CC_MODE (cmp->uses[0].code, a, b);
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	513 for (i = 1; i < n; ++i)
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	514 {
111 04ced10e8804 gcc 7 kono parents: 68 diff changeset	515 machine_mode new_mode = SELECT_CC_MODE (cmp->uses[i].code, a, b);
68 561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	516 if (new_mode != sel_mode)
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	517 {
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	518 sel_mode = targetm.cc_modes_compatible (sel_mode, new_mode);
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	519 if (sel_mode == VOIDmode)
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	520 return NULL;
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	521 }
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	522 }
111 04ced10e8804 gcc 7 kono parents: 68 diff changeset	523
68 561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	524 if (sel_mode != cmp->orig_mode)
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	525 {
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	526 flags = gen_rtx_REG (sel_mode, targetm.flags_regnum);
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	527 for (i = 0; i < n; ++i)
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	528 validate_change (cmp->uses[i].insn, cmp->uses[i].loc, flags, true);
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	529 }
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	530 }
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	531
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	532 return flags;
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	533 }
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	534
111 04ced10e8804 gcc 7 kono parents: 68 diff changeset	535 /* Return a register RTX holding the same value at START as REG at END, or
04ced10e8804 gcc 7 kono parents: 68 diff changeset	536 NULL_RTX if there is none. */
04ced10e8804 gcc 7 kono parents: 68 diff changeset	537
04ced10e8804 gcc 7 kono parents: 68 diff changeset	538 static rtx
04ced10e8804 gcc 7 kono parents: 68 diff changeset	539 equivalent_reg_at_start (rtx reg, rtx_insn end, rtx_insn start)
04ced10e8804 gcc 7 kono parents: 68 diff changeset	540 {
04ced10e8804 gcc 7 kono parents: 68 diff changeset	541 machine_mode orig_mode = GET_MODE (reg);
04ced10e8804 gcc 7 kono parents: 68 diff changeset	542 rtx_insn *bb_head = BB_HEAD (BLOCK_FOR_INSN (end));
04ced10e8804 gcc 7 kono parents: 68 diff changeset	543
04ced10e8804 gcc 7 kono parents: 68 diff changeset	544 for (rtx_insn *insn = PREV_INSN (end);
04ced10e8804 gcc 7 kono parents: 68 diff changeset	545 insn != start;
04ced10e8804 gcc 7 kono parents: 68 diff changeset	546 insn = PREV_INSN (insn))
04ced10e8804 gcc 7 kono parents: 68 diff changeset	547 {
04ced10e8804 gcc 7 kono parents: 68 diff changeset	548 const int abnormal_flags
04ced10e8804 gcc 7 kono parents: 68 diff changeset	549 = (DF_REF_CONDITIONAL \| DF_REF_PARTIAL \| DF_REF_MAY_CLOBBER
04ced10e8804 gcc 7 kono parents: 68 diff changeset	550 \| DF_REF_MUST_CLOBBER \| DF_REF_SIGN_EXTRACT
04ced10e8804 gcc 7 kono parents: 68 diff changeset	551 \| DF_REF_ZERO_EXTRACT \| DF_REF_STRICT_LOW_PART
04ced10e8804 gcc 7 kono parents: 68 diff changeset	552 \| DF_REF_PRE_POST_MODIFY);
04ced10e8804 gcc 7 kono parents: 68 diff changeset	553 df_ref def;
04ced10e8804 gcc 7 kono parents: 68 diff changeset	554
04ced10e8804 gcc 7 kono parents: 68 diff changeset	555 /* Note that the BB_HEAD is always either a note or a label, but in
04ced10e8804 gcc 7 kono parents: 68 diff changeset	556 any case it means that REG is defined outside the block. */
04ced10e8804 gcc 7 kono parents: 68 diff changeset	557 if (insn == bb_head)
04ced10e8804 gcc 7 kono parents: 68 diff changeset	558 return NULL_RTX;
04ced10e8804 gcc 7 kono parents: 68 diff changeset	559 if (NOTE_P (insn) \|\| DEBUG_INSN_P (insn))
04ced10e8804 gcc 7 kono parents: 68 diff changeset	560 continue;
04ced10e8804 gcc 7 kono parents: 68 diff changeset	561
04ced10e8804 gcc 7 kono parents: 68 diff changeset	562 /* Find a possible def of REG in INSN. */
04ced10e8804 gcc 7 kono parents: 68 diff changeset	563 FOR_EACH_INSN_DEF (def, insn)
04ced10e8804 gcc 7 kono parents: 68 diff changeset	564 if (DF_REF_REGNO (def) == REGNO (reg))
04ced10e8804 gcc 7 kono parents: 68 diff changeset	565 break;
04ced10e8804 gcc 7 kono parents: 68 diff changeset	566
04ced10e8804 gcc 7 kono parents: 68 diff changeset	567 /* No definitions of REG; continue searching. */
04ced10e8804 gcc 7 kono parents: 68 diff changeset	568 if (def == NULL)
04ced10e8804 gcc 7 kono parents: 68 diff changeset	569 continue;
04ced10e8804 gcc 7 kono parents: 68 diff changeset	570
04ced10e8804 gcc 7 kono parents: 68 diff changeset	571 /* Bail if this is not a totally normal set of REG. */
04ced10e8804 gcc 7 kono parents: 68 diff changeset	572 if (DF_REF_IS_ARTIFICIAL (def))
04ced10e8804 gcc 7 kono parents: 68 diff changeset	573 return NULL_RTX;
04ced10e8804 gcc 7 kono parents: 68 diff changeset	574 if (DF_REF_FLAGS (def) & abnormal_flags)
04ced10e8804 gcc 7 kono parents: 68 diff changeset	575 return NULL_RTX;
04ced10e8804 gcc 7 kono parents: 68 diff changeset	576
04ced10e8804 gcc 7 kono parents: 68 diff changeset	577 /* We've found an insn between the compare and the clobber that sets
04ced10e8804 gcc 7 kono parents: 68 diff changeset	578 REG. Given that pass_cprop_hardreg has not yet run, we still find
04ced10e8804 gcc 7 kono parents: 68 diff changeset	579 situations in which we can usefully look through a copy insn. */
04ced10e8804 gcc 7 kono parents: 68 diff changeset	580 rtx x = single_set (insn);
04ced10e8804 gcc 7 kono parents: 68 diff changeset	581 if (x == NULL_RTX)
04ced10e8804 gcc 7 kono parents: 68 diff changeset	582 return NULL_RTX;
04ced10e8804 gcc 7 kono parents: 68 diff changeset	583 reg = SET_SRC (x);
04ced10e8804 gcc 7 kono parents: 68 diff changeset	584 if (!REG_P (reg))
04ced10e8804 gcc 7 kono parents: 68 diff changeset	585 return NULL_RTX;
04ced10e8804 gcc 7 kono parents: 68 diff changeset	586 }
04ced10e8804 gcc 7 kono parents: 68 diff changeset	587
04ced10e8804 gcc 7 kono parents: 68 diff changeset	588 if (GET_MODE (reg) != orig_mode)
04ced10e8804 gcc 7 kono parents: 68 diff changeset	589 return NULL_RTX;
04ced10e8804 gcc 7 kono parents: 68 diff changeset	590
04ced10e8804 gcc 7 kono parents: 68 diff changeset	591 return reg;
04ced10e8804 gcc 7 kono parents: 68 diff changeset	592 }
04ced10e8804 gcc 7 kono parents: 68 diff changeset	593
04ced10e8804 gcc 7 kono parents: 68 diff changeset	594 /* Return true if it is okay to merge the comparison CMP_INSN with
04ced10e8804 gcc 7 kono parents: 68 diff changeset	595 the instruction ARITH_INSN. Both instructions are assumed to be in the
04ced10e8804 gcc 7 kono parents: 68 diff changeset	596 same basic block with ARITH_INSN appearing before CMP_INSN. This checks
04ced10e8804 gcc 7 kono parents: 68 diff changeset	597 that there are no uses or defs of the condition flags or control flow
04ced10e8804 gcc 7 kono parents: 68 diff changeset	598 changes between the two instructions. */
04ced10e8804 gcc 7 kono parents: 68 diff changeset	599
04ced10e8804 gcc 7 kono parents: 68 diff changeset	600 static bool
04ced10e8804 gcc 7 kono parents: 68 diff changeset	601 can_merge_compare_into_arith (rtx_insn cmp_insn, rtx_insn arith_insn)
04ced10e8804 gcc 7 kono parents: 68 diff changeset	602 {
04ced10e8804 gcc 7 kono parents: 68 diff changeset	603 for (rtx_insn *insn = PREV_INSN (cmp_insn);
04ced10e8804 gcc 7 kono parents: 68 diff changeset	604 insn && insn != arith_insn;
04ced10e8804 gcc 7 kono parents: 68 diff changeset	605 insn = PREV_INSN (insn))
04ced10e8804 gcc 7 kono parents: 68 diff changeset	606 {
04ced10e8804 gcc 7 kono parents: 68 diff changeset	607 if (!NONDEBUG_INSN_P (insn))
04ced10e8804 gcc 7 kono parents: 68 diff changeset	608 continue;
04ced10e8804 gcc 7 kono parents: 68 diff changeset	609 /* Bail if there are jumps or calls in between. */
04ced10e8804 gcc 7 kono parents: 68 diff changeset	610 if (!NONJUMP_INSN_P (insn))
04ced10e8804 gcc 7 kono parents: 68 diff changeset	611 return false;
04ced10e8804 gcc 7 kono parents: 68 diff changeset	612
04ced10e8804 gcc 7 kono parents: 68 diff changeset	613 /* Bail on old-style asm statements because they lack
04ced10e8804 gcc 7 kono parents: 68 diff changeset	614 data flow information. */
04ced10e8804 gcc 7 kono parents: 68 diff changeset	615 if (GET_CODE (PATTERN (insn)) == ASM_INPUT)
04ced10e8804 gcc 7 kono parents: 68 diff changeset	616 return false;
04ced10e8804 gcc 7 kono parents: 68 diff changeset	617
04ced10e8804 gcc 7 kono parents: 68 diff changeset	618 df_ref ref;
04ced10e8804 gcc 7 kono parents: 68 diff changeset	619 /* Find a USE of the flags register. */
04ced10e8804 gcc 7 kono parents: 68 diff changeset	620 FOR_EACH_INSN_USE (ref, insn)
04ced10e8804 gcc 7 kono parents: 68 diff changeset	621 if (DF_REF_REGNO (ref) == targetm.flags_regnum)
04ced10e8804 gcc 7 kono parents: 68 diff changeset	622 return false;
04ced10e8804 gcc 7 kono parents: 68 diff changeset	623
04ced10e8804 gcc 7 kono parents: 68 diff changeset	624 /* Find a DEF of the flags register. */
04ced10e8804 gcc 7 kono parents: 68 diff changeset	625 FOR_EACH_INSN_DEF (ref, insn)
04ced10e8804 gcc 7 kono parents: 68 diff changeset	626 if (DF_REF_REGNO (ref) == targetm.flags_regnum)
04ced10e8804 gcc 7 kono parents: 68 diff changeset	627 return false;
04ced10e8804 gcc 7 kono parents: 68 diff changeset	628 }
04ced10e8804 gcc 7 kono parents: 68 diff changeset	629 return true;
04ced10e8804 gcc 7 kono parents: 68 diff changeset	630 }
04ced10e8804 gcc 7 kono parents: 68 diff changeset	631
04ced10e8804 gcc 7 kono parents: 68 diff changeset	632 /* Given two SET expressions, SET_A and SET_B determine whether they form
04ced10e8804 gcc 7 kono parents: 68 diff changeset	633 a recognizable pattern when emitted in parallel. Return that parallel
04ced10e8804 gcc 7 kono parents: 68 diff changeset	634 if so. Otherwise return NULL. */
04ced10e8804 gcc 7 kono parents: 68 diff changeset	635
04ced10e8804 gcc 7 kono parents: 68 diff changeset	636 static rtx
04ced10e8804 gcc 7 kono parents: 68 diff changeset	637 try_validate_parallel (rtx set_a, rtx set_b)
04ced10e8804 gcc 7 kono parents: 68 diff changeset	638 {
131 84e7813d76e9 gcc-8.2 mir3636 parents: 111 diff changeset	639 rtx par = gen_rtx_PARALLEL (VOIDmode, gen_rtvec (2, set_a, set_b));
84e7813d76e9 gcc-8.2 mir3636 parents: 111 diff changeset	640 rtx_insn *insn = make_insn_raw (par);
111 04ced10e8804 gcc 7 kono parents: 68 diff changeset	641
131 84e7813d76e9 gcc-8.2 mir3636 parents: 111 diff changeset	642 if (insn_invalid_p (insn, false))
84e7813d76e9 gcc-8.2 mir3636 parents: 111 diff changeset	643 {
84e7813d76e9 gcc-8.2 mir3636 parents: 111 diff changeset	644 crtl->emit.x_cur_insn_uid--;
84e7813d76e9 gcc-8.2 mir3636 parents: 111 diff changeset	645 return NULL_RTX;
84e7813d76e9 gcc-8.2 mir3636 parents: 111 diff changeset	646 }
111 04ced10e8804 gcc 7 kono parents: 68 diff changeset	647
131 84e7813d76e9 gcc-8.2 mir3636 parents: 111 diff changeset	648 SET_PREV_INSN (insn) = NULL_RTX;
84e7813d76e9 gcc-8.2 mir3636 parents: 111 diff changeset	649 SET_NEXT_INSN (insn) = NULL_RTX;
84e7813d76e9 gcc-8.2 mir3636 parents: 111 diff changeset	650 INSN_LOCATION (insn) = 0;
84e7813d76e9 gcc-8.2 mir3636 parents: 111 diff changeset	651 return insn;
111 04ced10e8804 gcc 7 kono parents: 68 diff changeset	652 }
04ced10e8804 gcc 7 kono parents: 68 diff changeset	653
04ced10e8804 gcc 7 kono parents: 68 diff changeset	654 /* For a comparison instruction described by CMP check if it compares a
04ced10e8804 gcc 7 kono parents: 68 diff changeset	655 register with zero i.e. it is of the form CC := CMP R1, 0.
04ced10e8804 gcc 7 kono parents: 68 diff changeset	656 If it is, find the instruction defining R1 (say I1) and try to create a
04ced10e8804 gcc 7 kono parents: 68 diff changeset	657 PARALLEL consisting of I1 and the comparison, representing a flag-setting
04ced10e8804 gcc 7 kono parents: 68 diff changeset	658 arithmetic instruction. Example:
04ced10e8804 gcc 7 kono parents: 68 diff changeset	659 I1: R1 := R2 + R3
04ced10e8804 gcc 7 kono parents: 68 diff changeset	660 <instructions that don't read the condition register>
04ced10e8804 gcc 7 kono parents: 68 diff changeset	661 I2: CC := CMP R1 0
04ced10e8804 gcc 7 kono parents: 68 diff changeset	662 I2 can be merged with I1 into:
131 84e7813d76e9 gcc-8.2 mir3636 parents: 111 diff changeset	663 I1: { CC := CMP (R2 + R3) 0 ; R1 := R2 + R3 }
111 04ced10e8804 gcc 7 kono parents: 68 diff changeset	664 This catches cases where R1 is used between I1 and I2 and therefore
04ced10e8804 gcc 7 kono parents: 68 diff changeset	665 combine and other RTL optimisations will not try to propagate it into
04ced10e8804 gcc 7 kono parents: 68 diff changeset	666 I2. Return true if we succeeded in merging CMP. */
04ced10e8804 gcc 7 kono parents: 68 diff changeset	667
04ced10e8804 gcc 7 kono parents: 68 diff changeset	668 static bool
04ced10e8804 gcc 7 kono parents: 68 diff changeset	669 try_merge_compare (struct comparison *cmp)
04ced10e8804 gcc 7 kono parents: 68 diff changeset	670 {
04ced10e8804 gcc 7 kono parents: 68 diff changeset	671 rtx_insn *cmp_insn = cmp->insn;
04ced10e8804 gcc 7 kono parents: 68 diff changeset	672
131 84e7813d76e9 gcc-8.2 mir3636 parents: 111 diff changeset	673 if (cmp->in_b != const0_rtx \|\| cmp->in_a_setter == NULL)
111 04ced10e8804 gcc 7 kono parents: 68 diff changeset	674 return false;
04ced10e8804 gcc 7 kono parents: 68 diff changeset	675 rtx in_a = cmp->in_a;
04ced10e8804 gcc 7 kono parents: 68 diff changeset	676 df_ref use;
04ced10e8804 gcc 7 kono parents: 68 diff changeset	677
04ced10e8804 gcc 7 kono parents: 68 diff changeset	678 FOR_EACH_INSN_USE (use, cmp_insn)
04ced10e8804 gcc 7 kono parents: 68 diff changeset	679 if (DF_REF_REGNO (use) == REGNO (in_a))
04ced10e8804 gcc 7 kono parents: 68 diff changeset	680 break;
04ced10e8804 gcc 7 kono parents: 68 diff changeset	681 if (!use)
04ced10e8804 gcc 7 kono parents: 68 diff changeset	682 return false;
04ced10e8804 gcc 7 kono parents: 68 diff changeset	683
131 84e7813d76e9 gcc-8.2 mir3636 parents: 111 diff changeset	684 rtx_insn *def_insn = cmp->in_a_setter;
111 04ced10e8804 gcc 7 kono parents: 68 diff changeset	685 rtx set = single_set (def_insn);
04ced10e8804 gcc 7 kono parents: 68 diff changeset	686 if (!set)
04ced10e8804 gcc 7 kono parents: 68 diff changeset	687 return false;
04ced10e8804 gcc 7 kono parents: 68 diff changeset	688
04ced10e8804 gcc 7 kono parents: 68 diff changeset	689 if (!can_merge_compare_into_arith (cmp_insn, def_insn))
04ced10e8804 gcc 7 kono parents: 68 diff changeset	690 return false;
04ced10e8804 gcc 7 kono parents: 68 diff changeset	691
04ced10e8804 gcc 7 kono parents: 68 diff changeset	692 rtx src = SET_SRC (set);
131 84e7813d76e9 gcc-8.2 mir3636 parents: 111 diff changeset	693
84e7813d76e9 gcc-8.2 mir3636 parents: 111 diff changeset	694 /* If the source uses addressing modes with side effects, we can't
84e7813d76e9 gcc-8.2 mir3636 parents: 111 diff changeset	695 do the merge because we'd end up with a PARALLEL that has two
84e7813d76e9 gcc-8.2 mir3636 parents: 111 diff changeset	696 instances of that side effect in it. */
84e7813d76e9 gcc-8.2 mir3636 parents: 111 diff changeset	697 if (side_effects_p (src))
84e7813d76e9 gcc-8.2 mir3636 parents: 111 diff changeset	698 return false;
84e7813d76e9 gcc-8.2 mir3636 parents: 111 diff changeset	699
111 04ced10e8804 gcc 7 kono parents: 68 diff changeset	700 rtx flags = maybe_select_cc_mode (cmp, src, CONST0_RTX (GET_MODE (src)));
04ced10e8804 gcc 7 kono parents: 68 diff changeset	701 if (!flags)
04ced10e8804 gcc 7 kono parents: 68 diff changeset	702 {
04ced10e8804 gcc 7 kono parents: 68 diff changeset	703 /* We may already have a change group going through maybe_select_cc_mode.
04ced10e8804 gcc 7 kono parents: 68 diff changeset	704 Discard it properly. */
04ced10e8804 gcc 7 kono parents: 68 diff changeset	705 cancel_changes (0);
04ced10e8804 gcc 7 kono parents: 68 diff changeset	706 return false;
04ced10e8804 gcc 7 kono parents: 68 diff changeset	707 }
04ced10e8804 gcc 7 kono parents: 68 diff changeset	708
04ced10e8804 gcc 7 kono parents: 68 diff changeset	709 rtx flag_set
04ced10e8804 gcc 7 kono parents: 68 diff changeset	710 = gen_rtx_SET (flags, gen_rtx_COMPARE (GET_MODE (flags),
04ced10e8804 gcc 7 kono parents: 68 diff changeset	711 copy_rtx (src),
04ced10e8804 gcc 7 kono parents: 68 diff changeset	712 CONST0_RTX (GET_MODE (src))));
04ced10e8804 gcc 7 kono parents: 68 diff changeset	713 rtx arith_set = copy_rtx (PATTERN (def_insn));
04ced10e8804 gcc 7 kono parents: 68 diff changeset	714 rtx par = try_validate_parallel (flag_set, arith_set);
04ced10e8804 gcc 7 kono parents: 68 diff changeset	715 if (!par)
04ced10e8804 gcc 7 kono parents: 68 diff changeset	716 {
04ced10e8804 gcc 7 kono parents: 68 diff changeset	717 /* We may already have a change group going through maybe_select_cc_mode.
04ced10e8804 gcc 7 kono parents: 68 diff changeset	718 Discard it properly. */
04ced10e8804 gcc 7 kono parents: 68 diff changeset	719 cancel_changes (0);
04ced10e8804 gcc 7 kono parents: 68 diff changeset	720 return false;
04ced10e8804 gcc 7 kono parents: 68 diff changeset	721 }
04ced10e8804 gcc 7 kono parents: 68 diff changeset	722 if (!apply_change_group ())
04ced10e8804 gcc 7 kono parents: 68 diff changeset	723 return false;
04ced10e8804 gcc 7 kono parents: 68 diff changeset	724 emit_insn_after (par, def_insn);
04ced10e8804 gcc 7 kono parents: 68 diff changeset	725 delete_insn (def_insn);
04ced10e8804 gcc 7 kono parents: 68 diff changeset	726 delete_insn (cmp->insn);
04ced10e8804 gcc 7 kono parents: 68 diff changeset	727 return true;
04ced10e8804 gcc 7 kono parents: 68 diff changeset	728 }
04ced10e8804 gcc 7 kono parents: 68 diff changeset	729
68 561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	730 /* Attempt to replace a comparison with a prior arithmetic insn that can
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	731 compute the same flags value as the comparison itself. Return true if
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	732 successful, having made all rtl modifications necessary. */
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	733
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	734 static bool
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	735 try_eliminate_compare (struct comparison *cmp)
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	736 {
111 04ced10e8804 gcc 7 kono parents: 68 diff changeset	737 rtx flags, in_a, in_b, cmp_src;
68 561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	738
111 04ced10e8804 gcc 7 kono parents: 68 diff changeset	739 if (try_merge_compare (cmp))
04ced10e8804 gcc 7 kono parents: 68 diff changeset	740 return true;
04ced10e8804 gcc 7 kono parents: 68 diff changeset	741
04ced10e8804 gcc 7 kono parents: 68 diff changeset	742 /* We must have found an interesting "clobber" preceding the compare. */
04ced10e8804 gcc 7 kono parents: 68 diff changeset	743 if (cmp->prev_clobber == NULL)
68 561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	744 return false;
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	745
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	746 /* Verify that IN_A is not clobbered in between CMP and PREV_CLOBBER.
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	747 Given that this target requires this pass, we can assume that most
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	748 insns do clobber the flags, and so the distance between the compare
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	749 and the clobber is likely to be small. */
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	750 /* ??? This is one point at which one could argue that DF_REF_CHAIN would
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	751 be useful, but it is thought to be too heavy-weight a solution here. */
111 04ced10e8804 gcc 7 kono parents: 68 diff changeset	752 in_a = equivalent_reg_at_start (cmp->in_a, cmp->insn, cmp->prev_clobber);
04ced10e8804 gcc 7 kono parents: 68 diff changeset	753 if (!in_a)
04ced10e8804 gcc 7 kono parents: 68 diff changeset	754 return false;
68 561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	755
111 04ced10e8804 gcc 7 kono parents: 68 diff changeset	756 /* Likewise for IN_B if need be. */
04ced10e8804 gcc 7 kono parents: 68 diff changeset	757 if (CONSTANT_P (cmp->in_b))
04ced10e8804 gcc 7 kono parents: 68 diff changeset	758 in_b = cmp->in_b;
04ced10e8804 gcc 7 kono parents: 68 diff changeset	759 else if (REG_P (cmp->in_b))
04ced10e8804 gcc 7 kono parents: 68 diff changeset	760 {
04ced10e8804 gcc 7 kono parents: 68 diff changeset	761 in_b = equivalent_reg_at_start (cmp->in_b, cmp->insn, cmp->prev_clobber);
04ced10e8804 gcc 7 kono parents: 68 diff changeset	762 if (!in_b)
68 561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	763 return false;
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	764 }
111 04ced10e8804 gcc 7 kono parents: 68 diff changeset	765 else if (GET_CODE (cmp->in_b) == UNSPEC)
04ced10e8804 gcc 7 kono parents: 68 diff changeset	766 {
04ced10e8804 gcc 7 kono parents: 68 diff changeset	767 const int len = XVECLEN (cmp->in_b, 0);
04ced10e8804 gcc 7 kono parents: 68 diff changeset	768 rtvec v = rtvec_alloc (len);
04ced10e8804 gcc 7 kono parents: 68 diff changeset	769 for (int i = 0; i < len; i++)
04ced10e8804 gcc 7 kono parents: 68 diff changeset	770 {
04ced10e8804 gcc 7 kono parents: 68 diff changeset	771 rtx r = equivalent_reg_at_start (XVECEXP (cmp->in_b, 0, i),
04ced10e8804 gcc 7 kono parents: 68 diff changeset	772 cmp->insn, cmp->prev_clobber);
04ced10e8804 gcc 7 kono parents: 68 diff changeset	773 if (!r)
04ced10e8804 gcc 7 kono parents: 68 diff changeset	774 return false;
04ced10e8804 gcc 7 kono parents: 68 diff changeset	775 RTVEC_ELT (v, i) = r;
04ced10e8804 gcc 7 kono parents: 68 diff changeset	776 }
04ced10e8804 gcc 7 kono parents: 68 diff changeset	777 in_b = gen_rtx_UNSPEC (GET_MODE (cmp->in_b), v, XINT (cmp->in_b, 1));
04ced10e8804 gcc 7 kono parents: 68 diff changeset	778 }
04ced10e8804 gcc 7 kono parents: 68 diff changeset	779 else
04ced10e8804 gcc 7 kono parents: 68 diff changeset	780 gcc_unreachable ();
68 561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	781
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	782 /* We've reached PREV_CLOBBER without finding a modification of IN_A.
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	783 Validate that PREV_CLOBBER itself does in fact refer to IN_A. Do
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	784 recall that we've already validated the shape of PREV_CLOBBER. */
111 04ced10e8804 gcc 7 kono parents: 68 diff changeset	785 rtx_insn *insn = cmp->prev_clobber;
04ced10e8804 gcc 7 kono parents: 68 diff changeset	786
04ced10e8804 gcc 7 kono parents: 68 diff changeset	787 rtx x = XVECEXP (PATTERN (insn), 0, 0);
04ced10e8804 gcc 7 kono parents: 68 diff changeset	788 if (rtx_equal_p (SET_DEST (x), in_a))
04ced10e8804 gcc 7 kono parents: 68 diff changeset	789 cmp_src = SET_SRC (x);
04ced10e8804 gcc 7 kono parents: 68 diff changeset	790
04ced10e8804 gcc 7 kono parents: 68 diff changeset	791 /* Also check operations with implicit extensions, e.g.:
04ced10e8804 gcc 7 kono parents: 68 diff changeset	792 [(set (reg:DI)
04ced10e8804 gcc 7 kono parents: 68 diff changeset	793 (zero_extend:DI (plus:SI (reg:SI) (reg:SI))))
04ced10e8804 gcc 7 kono parents: 68 diff changeset	794 (set (reg:CCZ flags)
04ced10e8804 gcc 7 kono parents: 68 diff changeset	795 (compare:CCZ (plus:SI (reg:SI) (reg:SI))
04ced10e8804 gcc 7 kono parents: 68 diff changeset	796 (const_int 0)))] */
04ced10e8804 gcc 7 kono parents: 68 diff changeset	797 else if (REG_P (SET_DEST (x))
04ced10e8804 gcc 7 kono parents: 68 diff changeset	798 && REG_P (in_a)
04ced10e8804 gcc 7 kono parents: 68 diff changeset	799 && REGNO (SET_DEST (x)) == REGNO (in_a)
04ced10e8804 gcc 7 kono parents: 68 diff changeset	800 && (GET_CODE (SET_SRC (x)) == ZERO_EXTEND
04ced10e8804 gcc 7 kono parents: 68 diff changeset	801 \|\| GET_CODE (SET_SRC (x)) == SIGN_EXTEND)
04ced10e8804 gcc 7 kono parents: 68 diff changeset	802 && GET_MODE (XEXP (SET_SRC (x), 0)) == GET_MODE (in_a))
04ced10e8804 gcc 7 kono parents: 68 diff changeset	803 cmp_src = XEXP (SET_SRC (x), 0);
04ced10e8804 gcc 7 kono parents: 68 diff changeset	804
04ced10e8804 gcc 7 kono parents: 68 diff changeset	805 /* Also check fully redundant comparisons, e.g.:
04ced10e8804 gcc 7 kono parents: 68 diff changeset	806 [(set (reg:SI)
04ced10e8804 gcc 7 kono parents: 68 diff changeset	807 (minus:SI (reg:SI) (reg:SI))))
04ced10e8804 gcc 7 kono parents: 68 diff changeset	808 (set (reg:CC flags)
04ced10e8804 gcc 7 kono parents: 68 diff changeset	809 (compare:CC (reg:SI) (reg:SI)))] */
04ced10e8804 gcc 7 kono parents: 68 diff changeset	810 else if (REG_P (in_b)
04ced10e8804 gcc 7 kono parents: 68 diff changeset	811 && GET_CODE (SET_SRC (x)) == MINUS
04ced10e8804 gcc 7 kono parents: 68 diff changeset	812 && rtx_equal_p (XEXP (SET_SRC (x), 0), in_a)
04ced10e8804 gcc 7 kono parents: 68 diff changeset	813 && rtx_equal_p (XEXP (SET_SRC (x), 1), in_b))
04ced10e8804 gcc 7 kono parents: 68 diff changeset	814 cmp_src = in_a;
04ced10e8804 gcc 7 kono parents: 68 diff changeset	815
04ced10e8804 gcc 7 kono parents: 68 diff changeset	816 else
68 561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	817 return false;
111 04ced10e8804 gcc 7 kono parents: 68 diff changeset	818
131 84e7813d76e9 gcc-8.2 mir3636 parents: 111 diff changeset	819 /* If the source uses addressing modes with side effects, we can't
84e7813d76e9 gcc-8.2 mir3636 parents: 111 diff changeset	820 do the merge because we'd end up with a PARALLEL that has two
84e7813d76e9 gcc-8.2 mir3636 parents: 111 diff changeset	821 instances of that side effect in it. */
84e7813d76e9 gcc-8.2 mir3636 parents: 111 diff changeset	822 if (side_effects_p (cmp_src))
84e7813d76e9 gcc-8.2 mir3636 parents: 111 diff changeset	823 return false;
84e7813d76e9 gcc-8.2 mir3636 parents: 111 diff changeset	824
68 561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	825 /* Determine if we ought to use a different CC_MODE here. */
111 04ced10e8804 gcc 7 kono parents: 68 diff changeset	826 flags = maybe_select_cc_mode (cmp, cmp_src, in_b);
68 561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	827 if (flags == NULL)
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	828 flags = gen_rtx_REG (cmp->orig_mode, targetm.flags_regnum);
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	829
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	830 /* Generate a new comparison for installation in the setter. */
111 04ced10e8804 gcc 7 kono parents: 68 diff changeset	831 rtx y = copy_rtx (cmp_src);
04ced10e8804 gcc 7 kono parents: 68 diff changeset	832 y = gen_rtx_COMPARE (GET_MODE (flags), y, in_b);
04ced10e8804 gcc 7 kono parents: 68 diff changeset	833 y = gen_rtx_SET (flags, y);
68 561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	834
111 04ced10e8804 gcc 7 kono parents: 68 diff changeset	835 /* Canonicalize instruction to:
04ced10e8804 gcc 7 kono parents: 68 diff changeset	836 [(set (reg:CCM) (compare:CCM (operation) (immediate)))
04ced10e8804 gcc 7 kono parents: 68 diff changeset	837 (set (reg) (operation)] */
04ced10e8804 gcc 7 kono parents: 68 diff changeset	838
04ced10e8804 gcc 7 kono parents: 68 diff changeset	839 rtvec v = rtvec_alloc (2);
04ced10e8804 gcc 7 kono parents: 68 diff changeset	840 RTVEC_ELT (v, 0) = y;
04ced10e8804 gcc 7 kono parents: 68 diff changeset	841 RTVEC_ELT (v, 1) = x;
04ced10e8804 gcc 7 kono parents: 68 diff changeset	842
04ced10e8804 gcc 7 kono parents: 68 diff changeset	843 rtx pat = gen_rtx_PARALLEL (VOIDmode, v);
04ced10e8804 gcc 7 kono parents: 68 diff changeset	844
68 561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	845 /* Succeed if the new instruction is valid. Note that we may have started
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	846 a change group within maybe_select_cc_mode, therefore we must continue. */
111 04ced10e8804 gcc 7 kono parents: 68 diff changeset	847 validate_change (insn, &PATTERN (insn), pat, true);
04ced10e8804 gcc 7 kono parents: 68 diff changeset	848
68 561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	849 if (!apply_change_group ())
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	850 return false;
111 04ced10e8804 gcc 7 kono parents: 68 diff changeset	851
68 561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	852 /* Success. Delete the compare insn... */
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	853 delete_insn (cmp->insn);
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	854
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	855 /* ... and any notes that are now invalid due to multiple sets. */
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	856 x = find_regno_note (insn, REG_UNUSED, targetm.flags_regnum);
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	857 if (x)
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	858 remove_note (insn, x);
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	859 x = find_reg_note (insn, REG_EQUAL, NULL);
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	860 if (x)
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	861 remove_note (insn, x);
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	862 x = find_reg_note (insn, REG_EQUIV, NULL);
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	863 if (x)
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	864 remove_note (insn, x);
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	865
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	866 return true;
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	867 }
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	868
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	869 /* Main entry point to the pass. */
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	870
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	871 static unsigned int
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	872 execute_compare_elim_after_reload (void)
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	873 {
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	874 df_analyze ();
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	875
111 04ced10e8804 gcc 7 kono parents: 68 diff changeset	876 gcc_checking_assert (!all_compares.exists ());
68 561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	877
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	878 /* Locate all comparisons and their uses, and eliminate duplicates. */
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	879 find_comparisons ();
111 04ced10e8804 gcc 7 kono parents: 68 diff changeset	880 if (all_compares.exists ())
68 561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	881 {
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	882 struct comparison *cmp;
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	883 size_t i;
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	884
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	885 /* Eliminate comparisons that are redundant with flags computation. */
111 04ced10e8804 gcc 7 kono parents: 68 diff changeset	886 FOR_EACH_VEC_ELT (all_compares, i, cmp)
68 561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	887 {
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	888 try_eliminate_compare (cmp);
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	889 XDELETE (cmp);
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	890 }
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	891
111 04ced10e8804 gcc 7 kono parents: 68 diff changeset	892 all_compares.release ();
68 561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	893 }
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	894
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	895 return 0;
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	896 }
561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	897
111 04ced10e8804 gcc 7 kono parents: 68 diff changeset	898 namespace {
04ced10e8804 gcc 7 kono parents: 68 diff changeset	899
04ced10e8804 gcc 7 kono parents: 68 diff changeset	900 const pass_data pass_data_compare_elim_after_reload =
68 561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	901 {
111 04ced10e8804 gcc 7 kono parents: 68 diff changeset	902 RTL_PASS, /* type */
04ced10e8804 gcc 7 kono parents: 68 diff changeset	903 "cmpelim", /* name */
04ced10e8804 gcc 7 kono parents: 68 diff changeset	904 OPTGROUP_NONE, /* optinfo_flags */
04ced10e8804 gcc 7 kono parents: 68 diff changeset	905 TV_NONE, /* tv_id */
04ced10e8804 gcc 7 kono parents: 68 diff changeset	906 0, /* properties_required */
04ced10e8804 gcc 7 kono parents: 68 diff changeset	907 0, /* properties_provided */
04ced10e8804 gcc 7 kono parents: 68 diff changeset	908 0, /* properties_destroyed */
04ced10e8804 gcc 7 kono parents: 68 diff changeset	909 0, /* todo_flags_start */
04ced10e8804 gcc 7 kono parents: 68 diff changeset	910 ( TODO_df_finish \| TODO_df_verify ), /* todo_flags_finish */
04ced10e8804 gcc 7 kono parents: 68 diff changeset	911 };
68 561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	912
111 04ced10e8804 gcc 7 kono parents: 68 diff changeset	913 class pass_compare_elim_after_reload : public rtl_opt_pass
68 561a7518be6b update gcc-4.6 Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> parents: diff changeset	914 {
111 04ced10e8804 gcc 7 kono parents: 68 diff changeset	915 public:
04ced10e8804 gcc 7 kono parents: 68 diff changeset	916 pass_compare_elim_after_reload (gcc::context *ctxt)
04ced10e8804 gcc 7 kono parents: 68 diff changeset	917 : rtl_opt_pass (pass_data_compare_elim_after_reload, ctxt)
04ced10e8804 gcc 7 kono parents: 68 diff changeset	918 {}
04ced10e8804 gcc 7 kono parents: 68 diff changeset	919
04ced10e8804 gcc 7 kono parents: 68 diff changeset	920 /* opt_pass methods: */
04ced10e8804 gcc 7 kono parents: 68 diff changeset	921 virtual bool gate (function *)
04ced10e8804 gcc 7 kono parents: 68 diff changeset	922 {
04ced10e8804 gcc 7 kono parents: 68 diff changeset	923 /* Setting this target hook value is how a backend indicates the need. */
04ced10e8804 gcc 7 kono parents: 68 diff changeset	924 if (targetm.flags_regnum == INVALID_REGNUM)
04ced10e8804 gcc 7 kono parents: 68 diff changeset	925 return false;
04ced10e8804 gcc 7 kono parents: 68 diff changeset	926 return flag_compare_elim_after_reload;
04ced10e8804 gcc 7 kono parents: 68 diff changeset	927 }
04ced10e8804 gcc 7 kono parents: 68 diff changeset	928
04ced10e8804 gcc 7 kono parents: 68 diff changeset	929 virtual unsigned int execute (function *)
04ced10e8804 gcc 7 kono parents: 68 diff changeset	930 {
04ced10e8804 gcc 7 kono parents: 68 diff changeset	931 return execute_compare_elim_after_reload ();
04ced10e8804 gcc 7 kono parents: 68 diff changeset	932 }
04ced10e8804 gcc 7 kono parents: 68 diff changeset	933
04ced10e8804 gcc 7 kono parents: 68 diff changeset	934 }; // class pass_compare_elim_after_reload
04ced10e8804 gcc 7 kono parents: 68 diff changeset	935
04ced10e8804 gcc 7 kono parents: 68 diff changeset	936 } // anon namespace
04ced10e8804 gcc 7 kono parents: 68 diff changeset	937
04ced10e8804 gcc 7 kono parents: 68 diff changeset	938 rtl_opt_pass *
04ced10e8804 gcc 7 kono parents: 68 diff changeset	939 make_pass_compare_elim_after_reload (gcc::context *ctxt)
04ced10e8804 gcc 7 kono parents: 68 diff changeset	940 {
04ced10e8804 gcc 7 kono parents: 68 diff changeset	941 return new pass_compare_elim_after_reload (ctxt);
04ced10e8804 gcc 7 kono parents: 68 diff changeset	942 }

Mercurial > hg > CbC > CbC_gcc

annotate gcc/compare-elim.c @ 131:84e7813d76e9