[InstCombine] simplify code for shuffle mask canonicalization; NFC
We never use the local 'Mask' before returning, so that was dead code.
diff --git a/llvm/lib/Transforms/InstCombine/InstCombineVectorOps.cpp b/llvm/lib/Transforms/InstCombine/InstCombineVectorOps.cpp
index 2f9d342..fd31f52 100644
--- a/llvm/lib/Transforms/InstCombine/InstCombineVectorOps.cpp
+++ b/llvm/lib/Transforms/InstCombine/InstCombineVectorOps.cpp
@@ -1900,13 +1900,11 @@
continue;
}
- if (Mask[i] < (int)LHSWidth && isa<UndefValue>(LHS)) {
- Mask[i] = -1; // Turn into undef.
+ // Change select of undef to undef mask element or force to LHS.
+ if (Mask[i] < (int)LHSWidth && isa<UndefValue>(LHS))
Elts.push_back(UndefValue::get(Int32Ty));
- } else {
- Mask[i] = Mask[i] % LHSWidth; // Force to LHS.
- Elts.push_back(ConstantInt::get(Int32Ty, Mask[i]));
- }
+ else
+ Elts.push_back(ConstantInt::get(Int32Ty, Mask[i] % LHSWidth));
}
SVI.setOperand(0, SVI.getOperand(1));
SVI.setOperand(1, UndefValue::get(RHS->getType()));