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author | Roger Sayle <roger@nextmovesoftware.com> | 2020-06-24 19:18:03 +0000 |
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committer | Segher Boessenkool <segher@kernel.crashing.org> | 2020-06-24 19:27:57 +0000 |
commit | 0c586913e61021681e3221e8760cd87b24142aea (patch) | |
tree | e38ce13f24f1481798513b381d2c9321d71b94c4 /gcc | |
parent | 35eca8c5e16933b5cdb17eac4ed51e6b3877b288 (diff) | |
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simplify-rtx: Simplify rotates by zero
2020-06-24 Roger Sayle <roger@nextmovesoftware.com>
Segher Boessenkool <segher@kernel.crashing.org>
* simplify-rtx.c (simplify_unary_operation_1): Simplify rotates by 0.
Diffstat (limited to 'gcc')
-rw-r--r-- | gcc/simplify-rtx.c | 2 |
1 files changed, 2 insertions, 0 deletions
diff --git a/gcc/simplify-rtx.c b/gcc/simplify-rtx.c index 65008ea..3e913b5 100644 --- a/gcc/simplify-rtx.c +++ b/gcc/simplify-rtx.c @@ -3645,6 +3645,8 @@ simplify_binary_operation_1 (enum rtx_code code, machine_mode mode, case ROTATERT: case ROTATE: + if (trueop1 == CONST0_RTX (mode)) + return op0; /* Canonicalize rotates by constant amount. If op1 is bitsize / 2, prefer left rotation, if op1 is from bitsize / 2 + 1 to bitsize - 1, use other direction of rotate with 1 .. bitsize / 2 - 1 |