1 files changed, 5 insertions, 0 deletions
diff --git a/llvm/lib/CodeGen/SelectionDAG/DAGCombiner.cpp b/llvm/lib/CodeGen/SelectionDAG/DAGCombiner.cpp
index 255ddcacfdb..b7f9dad23ae 100644
--- a/llvm/lib/CodeGen/SelectionDAG/DAGCombiner.cpp
+++ b/llvm/lib/CodeGen/SelectionDAG/DAGCombiner.cpp
@@ -14055,6 +14055,11 @@ SDValue DAGCombiner::createBuildVecShuffle(const SDLoc &DL, SDNode *N,
         // when we start sorting the vectors by type.
         return SDValue();
       }
+    } else if (InVT2.getSizeInBits() * 2 == VT.getSizeInBits() &&
+               InVT1.getSizeInBits() == VT.getSizeInBits()) {
+      SmallVector<SDValue, 2> ConcatOps(2, DAG.getUNDEF(InVT2));
+      ConcatOps[0] = VecIn2;
+      VecIn2 = DAG.getNode(ISD::CONCAT_VECTORS, DL, VT, ConcatOps);
     } else {
       // TODO: Support cases where the length mismatch isn't exactly by a
       // factor of 2.