Address review comment

Author: preames

llvm/lib/Target/RISCV/RISCVISelLowering.cpp

@@ -5805,19 +5805,16 @@ bool RISCVTargetLowering::isShuffleMaskLegal(ArrayRef<int> M, EVT VT) const {
   if (ShuffleVectorSDNode::isSplatMask(M.data(), VT))
     return true;
 
+  const unsigned NumElts = M.size();
   MVT SVT = VT.getSimpleVT();
 
   // Not for i1 vectors.
   if (SVT.getScalarType() == MVT::i1)
     return false;
 
-  unsigned NumElts = M.size();
-  if (ShuffleVectorInst::isReverseMask(M, NumElts) &&
-      ShuffleVectorInst::isSingleSourceMask(M, NumElts))
-    return true;
-
   int Dummy1, Dummy2;
-  return (isElementRotate(Dummy1, Dummy2, M) > 0) ||
+  return ShuffleVectorInst::isReverseMask(M, NumElts) ||
+         (isElementRotate(Dummy1, Dummy2, M) > 0) ||
          isInterleaveShuffle(M, SVT, Dummy1, Dummy2, Subtarget);
 }