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| author | Amara Emerson <aemerson@apple.com> | 2019-07-09 16:05:59 +0000 |
|---|---|---|
| committer | Amara Emerson <aemerson@apple.com> | 2019-07-09 16:05:59 +0000 |
| commit | 6616e269a690b12335946c4cd019ef298ed0b288 (patch) | |
| tree | db9b60a6db80777b0de1eb174c99696327178a7a /llvm/lib/Target | |
| parent | d088720edad9c29ee0d622b5d69092e18a9ac0bd (diff) | |
| download | bcm5719-llvm-6616e269a690b12335946c4cd019ef298ed0b288.tar.gz bcm5719-llvm-6616e269a690b12335946c4cd019ef298ed0b288.zip | |
[AArch64][GlobalISel] Optimize conditional branches followed by unconditional branches
If we have an icmp->brcond->br sequence where the brcond just branches to the
next block jumping over the br, while the br takes the false edge, then we can
modify the conditional branch to jump to the br's target while inverting the
condition of the incoming icmp. This means we can eliminate the br as an
unconditional branch to the fallthrough block.
Differential Revision: https://reviews.llvm.org/D64354
llvm-svn: 365510
Diffstat (limited to 'llvm/lib/Target')
| -rw-r--r-- | llvm/lib/Target/AArch64/AArch64PreLegalizerCombiner.cpp | 2 |
1 files changed, 2 insertions, 0 deletions
diff --git a/llvm/lib/Target/AArch64/AArch64PreLegalizerCombiner.cpp b/llvm/lib/Target/AArch64/AArch64PreLegalizerCombiner.cpp index fe8216a8d1f..5f7245bfbd7 100644 --- a/llvm/lib/Target/AArch64/AArch64PreLegalizerCombiner.cpp +++ b/llvm/lib/Target/AArch64/AArch64PreLegalizerCombiner.cpp @@ -45,6 +45,8 @@ bool AArch64PreLegalizerCombinerInfo::combine(GISelChangeObserver &Observer, return false; case TargetOpcode::COPY: return Helper.tryCombineCopy(MI); + case TargetOpcode::G_BR: + return Helper.tryCombineBr(MI); case TargetOpcode::G_LOAD: case TargetOpcode::G_SEXTLOAD: case TargetOpcode::G_ZEXTLOAD: |
