| commit | 8f01b96d93b557de0c860be4f5512bde3c31ed64 | [log] [tgz] |
|---|---|---|
| author | David Majnemer <david.majnemer@gmail.com> | Wed Mar 18 00:03:36 2015 +0000 |
| committer | David Majnemer <david.majnemer@gmail.com> | Wed Mar 18 00:03:36 2015 +0000 |
| tree | bf7db0b8eeec3c01181eb0db9312b80e41a0fa1f | |
| parent | 7605cdd6e4926a0f0f15ebb81e21f41b8a378488 [diff] |
DAGCombiner: fold (xor (shl 1, x), -1) -> (rotl ~1, x) Targets which provide a rotate make it possible to replace a sequence of (XOR (SHL 1, x), -1) with (ROTL ~1, x). This saves an instruction on architectures like X86 and POWER(64). Differential Revision: http://reviews.llvm.org/D8350 git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@232572 91177308-0d34-0410-b5e6-96231b3b80d8