diff options
Diffstat (limited to 'llvm/lib/Transforms')
| -rw-r--r-- | llvm/lib/Transforms/InstCombine/InstCombineSimplifyDemanded.cpp | 6 |
1 files changed, 5 insertions, 1 deletions
diff --git a/llvm/lib/Transforms/InstCombine/InstCombineSimplifyDemanded.cpp b/llvm/lib/Transforms/InstCombine/InstCombineSimplifyDemanded.cpp index 2dea7eea404..1d52938d1f8 100644 --- a/llvm/lib/Transforms/InstCombine/InstCombineSimplifyDemanded.cpp +++ b/llvm/lib/Transforms/InstCombine/InstCombineSimplifyDemanded.cpp @@ -1437,7 +1437,11 @@ Value *InstCombiner::SimplifyDemandedVectorElts(Value *V, APInt DemandedElts, switch (II->getIntrinsicID()) { case Intrinsic::masked_gather: // fallthrough case Intrinsic::masked_load: { - APInt DemandedPtrs(DemandedElts), DemandedPassThrough(DemandedElts); + // Subtlety: If we load from a pointer, the pointer must be valid + // regardless of whether the element is demanded. Doing otherwise risks + // segfaults which didn't exist in the original program. + APInt DemandedPtrs(APInt::getAllOnesValue(VWidth)), + DemandedPassThrough(DemandedElts); if (auto *CV = dyn_cast<ConstantVector>(II->getOperand(2))) for (unsigned i = 0; i < VWidth; i++) { Constant *CElt = CV->getAggregateElement(i); |
