1 /* Match-and-simplify patterns for shared GENERIC and GIMPLE folding.
2 This file is consumed by genmatch which produces gimple-match.c
3 and generic-match.c from it.
5 Copyright (C) 2014 Free Software Foundation, Inc.
6 Contributed by Richard Biener <rguenther@suse.de>
7 and Prathamesh Kulkarni <bilbotheelffriend@gmail.com>
9 This file is part of GCC.
11 GCC is free software; you can redistribute it and/or modify it under
12 the terms of the GNU General Public License as published by the Free
13 Software Foundation; either version 3, or (at your option) any later
16 GCC is distributed in the hope that it will be useful, but WITHOUT ANY
17 WARRANTY; without even the implied warranty of MERCHANTABILITY or
18 FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
21 You should have received a copy of the GNU General Public License
22 along with GCC; see the file COPYING3. If not see
23 <http://www.gnu.org/licenses/>. */
26 /* Generic tree predicates we inherit. */
28 integer_onep integer_zerop integer_all_onesp
31 tree_expr_nonnegative_p)
34 /* Simplifications of operations with one constant operand and
35 simplifications to constants or single values. */
37 (for op (plus pointer_plus minus bit_ior bit_xor)
43 This is unsafe for certain floats even in non-IEEE formats.
44 In IEEE, it is unsafe because it does wrong for NaNs.
45 Also note that operand_equal_p is always false if an operand
49 (if (!FLOAT_TYPE_P (type) || !HONOR_NANS (TYPE_MODE (type)))
50 { build_zero_cst (type); }))
53 (mult @0 integer_zerop@1)
56 /* Make sure to preserve divisions by zero. This is the reason why
57 we don't simplify x / x to 1 or 0 / x to 0. */
58 (for op (mult trunc_div ceil_div floor_div round_div exact_div)
63 /* Same applies to modulo operations, but fold is inconsistent here
64 and simplifies 0 % x to 0, only preserving literal 0 % 0. */
65 (for op (ceil_mod floor_mod round_mod trunc_mod)
66 /* 0 % X is always zero. */
68 (op integer_zerop@0 @1)
69 /* But not for 0 % 0 so that we can get the proper warnings and errors. */
70 (if (!integer_zerop (@1))
72 /* X % 1 is always zero. */
75 { build_zero_cst (type); }))
79 (bit_ior @0 integer_all_onesp@1)
84 (bit_and @0 integer_zerop@1)
90 { build_zero_cst (type); })
92 /* Canonicalize X ^ ~0 to ~X. */
94 (bit_xor @0 integer_all_onesp@1)
99 (bit_and @0 integer_all_onesp)
102 /* x & x -> x, x | x -> x */
103 (for bitop (bit_and bit_ior)
112 (abs tree_expr_nonnegative_p@0)
116 /* Simplifications of conversions. */
118 /* Basic strip-useless-type-conversions / strip_nops. */
119 (for cvt (convert view_convert float fix_trunc)
122 (if ((GIMPLE && useless_type_conversion_p (type, TREE_TYPE (@0)))
123 || (GENERIC && type == TREE_TYPE (@0)))
126 /* Contract view-conversions. */
128 (view_convert (view_convert @0))
131 /* For integral conversions with the same precision or pointer
132 conversions use a NOP_EXPR instead. */
135 (if ((INTEGRAL_TYPE_P (type) || POINTER_TYPE_P (type))
136 && (INTEGRAL_TYPE_P (TREE_TYPE (@0)) || POINTER_TYPE_P (TREE_TYPE (@0)))
137 && TYPE_PRECISION (type) == TYPE_PRECISION (TREE_TYPE (@0)))
140 /* Strip inner integral conversions that do not change precision or size. */
142 (view_convert (convert@0 @1))
143 (if ((INTEGRAL_TYPE_P (TREE_TYPE (@0)) || POINTER_TYPE_P (TREE_TYPE (@0)))
144 && (INTEGRAL_TYPE_P (TREE_TYPE (@1)) || POINTER_TYPE_P (TREE_TYPE (@1)))
145 && (TYPE_PRECISION (TREE_TYPE (@0)) == TYPE_PRECISION (TREE_TYPE (@1)))
146 && (TYPE_SIZE (TREE_TYPE (@0)) == TYPE_SIZE (TREE_TYPE (@1))))
149 /* Re-association barriers around constants and other re-association
150 barriers can be removed. */
152 (paren CONSTANT_CLASS_P@0)