diff options
Diffstat (limited to 'llvm/lib/CodeGen/SelectionDAG')
| -rw-r--r-- | llvm/lib/CodeGen/SelectionDAG/DAGCombiner.cpp | 6 |
1 files changed, 6 insertions, 0 deletions
diff --git a/llvm/lib/CodeGen/SelectionDAG/DAGCombiner.cpp b/llvm/lib/CodeGen/SelectionDAG/DAGCombiner.cpp index 40ce46a0d79..bc051f07bb2 100644 --- a/llvm/lib/CodeGen/SelectionDAG/DAGCombiner.cpp +++ b/llvm/lib/CodeGen/SelectionDAG/DAGCombiner.cpp @@ -8320,6 +8320,9 @@ SDValue DAGCombiner::visitBITCAST(SDNode *N) { SDValue N0 = N->getOperand(0); EVT VT = N->getValueType(0); + if (N0.isUndef()) + return DAG.getUNDEF(VT); + // If the input is a BUILD_VECTOR with all constant elements, fold this now. // Only do this before legalize, since afterward the target may be depending // on the bitconvert. @@ -13189,6 +13192,9 @@ SDValue DAGCombiner::visitEXTRACT_VECTOR_ELT(SDNode *N) { EVT VT = InVec.getValueType(); EVT NVT = N->getValueType(0); + if (InVec.isUndef()) + return DAG.getUNDEF(NVT); + if (InVec.getOpcode() == ISD::SCALAR_TO_VECTOR) { // Check if the result type doesn't match the inserted element type. A // SCALAR_TO_VECTOR may truncate the inserted element and the |

