diff options
| author | Richard Sandiford <richard.sandiford@arm.com> | 2015-10-13 07:34:41 +0000 |
|---|---|---|
| committer | Richard Sandiford <rsandifo@gcc.gnu.org> | 2015-10-13 07:34:41 +0000 |
| commit | 9b054b08813d37586d6765fd087b0fc85dc94daf (patch) | |
| tree | ce58f25ea3acb2f496d0e9a22bb891f6e38e668d /gcc/match.pd | |
| parent | 6696de8a7f7e9bf37e2b9358ad5608dc863ad7a4 (diff) | |
| download | gcc-9b054b08813d37586d6765fd087b0fc85dc94daf.zip gcc-9b054b08813d37586d6765fd087b0fc85dc94daf.tar.gz gcc-9b054b08813d37586d6765fd087b0fc85dc94daf.tar.bz2 | |
To...
To: gcc-patches@gcc.gnu.org
Subject: Add an extra pow rule to match.pd
From: Richard Sandiford <richard.sandiford@arm.com>
Gcc: private.sent
--text follows this line--
Simplify pow(|x|,y) and pow(-x,y) to pow(x,y) if y is an even integer.
At the moment this duplicates a case in fold_builtin_pow, but an
upcoming patch will move all the fold_builtin_pow rules to match.pd.
I'm doing this one early to fix a regression in builtin-10.c for
soft-float ARM.
gcc/
* real.h (real_isinteger): Declare.
* real.c (real_isinteger): New function.
* match.pd: Simplify pow(|x|,y) and pow(-x,y) to pow(x,y)
if y is an even integer.
From-SVN: r228750
Diffstat (limited to 'gcc/match.pd')
| -rw-r--r-- | gcc/match.pd | 17 |
1 files changed, 12 insertions, 5 deletions
diff --git a/gcc/match.pd b/gcc/match.pd index b02dd03..6714796 100644 --- a/gcc/match.pd +++ b/gcc/match.pd @@ -309,12 +309,19 @@ along with GCC; see the file COPYING3. If not see && TYPE_OVERFLOW_UNDEFINED (type)) @0))) -/* Simplify cos (-x) -> cos (x). */ (for op (negate abs) -(for coss (COS COSH) - (simplify - (coss (op @0)) - (coss @0)))) + /* Simplify cos(-x) and cos(|x|) -> cos(x). Similarly for cosh. */ + (for coss (COS COSH) + (simplify + (coss (op @0)) + (coss @0))) + /* Simplify pow(-x, y) and pow(|x|,y) -> pow(x,y) if y is an even integer. */ + (for pows (POW) + (simplify + (pows (op @0) REAL_CST@1) + (with { HOST_WIDE_INT n; } + (if (real_isinteger (&TREE_REAL_CST (@1), &n) && (n & 1) == 0) + (pows @0 @1)))))) /* X % Y is smaller than Y. */ (for cmp (lt ge) |