blob: 3e6b25c2b01d5dc1f85bd27f507743ced5351c3f (
plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
|
/* Match-and-simplify patterns for shared GENERIC and GIMPLE folding.
This file is consumed by genmatch which produces gimple-match.c
and generic-match.c from it.
Copyright (C) 2014 Free Software Foundation, Inc.
Contributed by Richard Biener <rguenther@suse.de>
and Prathamesh Kulkarni <bilbotheelffriend@gmail.com>
This file is part of GCC.
GCC is free software; you can redistribute it and/or modify it under
the terms of the GNU General Public License as published by the Free
Software Foundation; either version 3, or (at your option) any later
version.
GCC is distributed in the hope that it will be useful, but WITHOUT ANY
WARRANTY; without even the implied warranty of MERCHANTABILITY or
FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
for more details.
You should have received a copy of the GNU General Public License
along with GCC; see the file COPYING3. If not see
<http://www.gnu.org/licenses/>. */
/* Generic tree predicates we inherit. */
(define_predicates
integer_onep integer_zerop integer_all_onesp
real_zerop real_onep
CONSTANT_CLASS_P)
/* Simplifications of operations with one constant operand and
simplifications to constants. */
(for op (plus pointer_plus minus bit_ior bit_xor)
(simplify
(op @0 integer_zerop)
(non_lvalue @0)))
/* Simplify x - x.
This is unsafe for certain floats even in non-IEEE formats.
In IEEE, it is unsafe because it does wrong for NaNs.
Also note that operand_equal_p is always false if an operand
is volatile. */
(simplify
(minus @0 @0)
(if (!FLOAT_TYPE_P (type) || !HONOR_NANS (TYPE_MODE (type)))
{ build_zero_cst (type); }))
(simplify
(mult @0 integer_zerop@1)
@1)
/* Make sure to preserve divisions by zero. This is the reason why
we don't simplify x / x to 1 or 0 / x to 0. */
(for op (mult trunc_div ceil_div floor_div round_div exact_div)
(simplify
(op @0 integer_onep)
(non_lvalue @0)))
/* Same applies to modulo operations, but fold is inconsistent here
and simplifies 0 % x to 0, only preserving literal 0 % 0. */
(for op (ceil_mod floor_mod round_mod trunc_mod)
/* 0 % X is always zero. */
(simplify
(op integer_zerop@0 @1)
/* But not for 0 % 0 so that we can get the proper warnings and errors. */
(if (!integer_zerop (@1))
@0))
/* X % 1 is always zero. */
(simplify
(op @0 integer_onep)
{ build_zero_cst (type); }))
/* x | ~0 -> ~0 */
(simplify
(bit_ior @0 integer_all_onesp@1)
@1)
/* x & 0 -> 0 */
(simplify
(bit_and @0 integer_zerop@1)
@1)
/* x ^ x -> 0 */
(simplify
(bit_xor @0 @0)
{ build_zero_cst (type); })
|
