diff options
| author | Bob Wilson <bob.wilson@apple.com> | 2010-02-12 01:30:21 +0000 |
|---|---|---|
| committer | Bob Wilson <bob.wilson@apple.com> | 2010-02-12 01:30:21 +0000 |
| commit | fe61fb1e1082c81653ed78efd6d471592a2e57ad (patch) | |
| tree | df0bb339b5cb79a8d22e66430b920e47fae100a5 /include | |
| parent | ccfa1db5380fd3089fc68f3ed9ccfe6a41d7a309 (diff) | |
Add a new pass on machine instructions to optimize away PHI cycles that
reduce down to a single value. InstCombine already does this transformation
but DAG legalization may introduce new opportunities. This has turned out to
be important for ARM where 64-bit values are split up during type legalization:
InstCombine is not able to remove the PHI cycles on the 64-bit values but
the separate 32-bit values can be optimized. I measured the compile time
impact of this (running llc on 176.gcc) and it was not significant.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@95951 91177308-0d34-0410-b5e6-96231b3b80d8
Diffstat (limited to 'include')
| -rw-r--r-- | include/llvm/CodeGen/Passes.h | 4 |
1 files changed, 4 insertions, 0 deletions
diff --git a/include/llvm/CodeGen/Passes.h b/include/llvm/CodeGen/Passes.h index 7e0da3f6a8..dbc73cbc54 100644 --- a/include/llvm/CodeGen/Passes.h +++ b/include/llvm/CodeGen/Passes.h @@ -174,6 +174,10 @@ namespace llvm { /// optimization by increasing uses of extended values. FunctionPass *createOptimizeExtsPass(); + /// createOptimizePHIsPass - This pass optimizes machine instruction PHIs + /// to take advantage of opportunities created during DAG legalization. + FunctionPass *createOptimizePHIsPass(); + /// createStackSlotColoringPass - This pass performs stack slot coloring. FunctionPass *createStackSlotColoringPass(bool); |