Rejected 169195. As Duncan commented, bitcasting to proper type is wrong approach. We need to insert some valid TRANCATE node here.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@162354 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/CodeGen/SelectionDAG/DAGCombiner.cpp b/lib/CodeGen/SelectionDAG/DAGCombiner.cpp
index 1c485a0..4e29879 100644
--- a/lib/CodeGen/SelectionDAG/DAGCombiner.cpp
+++ b/lib/CodeGen/SelectionDAG/DAGCombiner.cpp
@@ -7876,29 +7876,9 @@
if (VecIn1.getValueType().getSizeInBits()*2 != VT.getSizeInBits())
return SDValue();
- // If the element type of the input vector is not the same as
- // the output element type, make concat_vectors based on input element
- // type and then bitcast it to the output vector type.
- //
- // In another words avoid nodes like this:
- // <NODE> v16i8 = concat_vectors v4i16 v4i16
- // Replace it with this one:
- // <NODE0> v8i16 = concat_vectors v4i16 v4i16
- // <NODE1> v16i8 = bitcast NODE0
- EVT ItemType = VecIn1.getValueType().getVectorElementType();
- if (ItemType != VT.getVectorElementType()) {
- EVT ConcatVT = EVT::getVectorVT(*DAG.getContext(),
- ItemType,
- VecIn1.getValueType().getVectorNumElements()*2);
- // Widen the input vector by adding undef values.
- VecIn1 = DAG.getNode(ISD::CONCAT_VECTORS, dl, ConcatVT,
- VecIn1, DAG.getUNDEF(VecIn1.getValueType()));
- VecIn1 = DAG.getNode(ISD::BITCAST, dl, VT, VecIn1);
- } else
- // Widen the input vector by adding undef values.
- VecIn1 = DAG.getNode(ISD::CONCAT_VECTORS, dl, VT,
- VecIn1, DAG.getUNDEF(VecIn1.getValueType()));
-
+ // Widen the input vector by adding undef values.
+ VecIn1 = DAG.getNode(ISD::CONCAT_VECTORS, N->getDebugLoc(), VT,
+ VecIn1, DAG.getUNDEF(VecIn1.getValueType()));
}
// If VecIn2 is unused then change it to undef.