diff options
Diffstat (limited to 'llvm/lib/CodeGen/SelectionDAG/DAGCombiner.cpp')
| -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 b35c84f8da0..24f019d55c9 100644 --- a/llvm/lib/CodeGen/SelectionDAG/DAGCombiner.cpp +++ b/llvm/lib/CodeGen/SelectionDAG/DAGCombiner.cpp @@ -7240,6 +7240,12 @@ SDValue DAGCombiner::visitSELECT(SDNode *N) { if (N1 == N2) return N1; + // fold (select, C, X, undef) -> X + if (N2.isUndef()) + return N1; + if (N1.isUndef()) + return N2; + if (const ConstantSDNode *N0C = dyn_cast<const ConstantSDNode>(N0)) { // fold (select true, X, Y) -> X // fold (select false, X, Y) -> Y |
