diff options
Diffstat (limited to 'llvm/lib/Transforms/InstCombine/InstCombineSimplifyDemanded.cpp')
| -rw-r--r-- | llvm/lib/Transforms/InstCombine/InstCombineSimplifyDemanded.cpp | 6 |
1 files changed, 6 insertions, 0 deletions
diff --git a/llvm/lib/Transforms/InstCombine/InstCombineSimplifyDemanded.cpp b/llvm/lib/Transforms/InstCombine/InstCombineSimplifyDemanded.cpp index dd789fad569..279f44c2eae 100644 --- a/llvm/lib/Transforms/InstCombine/InstCombineSimplifyDemanded.cpp +++ b/llvm/lib/Transforms/InstCombine/InstCombineSimplifyDemanded.cpp @@ -834,6 +834,12 @@ Value *InstCombiner::SimplifyMultipleUseDemandedBits(Instruction *I, // Compute the KnownZero/KnownOne bits to simplify things downstream. computeKnownBits(I, KnownZero, KnownOne, Depth, CxtI); + + // If this user is only demanding bits that we know, return the known + // constant. + if ((DemandedMask & (KnownZero|KnownOne)) == DemandedMask) + return Constant::getIntegerValue(ITy, KnownOne); + return nullptr; } |
