diff options
| -rw-r--r-- | lib/CodeGen/SelectionDAG/DAGCombiner.cpp | 5 |
1 files changed, 5 insertions, 0 deletions
diff --git a/lib/CodeGen/SelectionDAG/DAGCombiner.cpp b/lib/CodeGen/SelectionDAG/DAGCombiner.cpp index 9c469b53c7..e90f902736 100644 --- a/lib/CodeGen/SelectionDAG/DAGCombiner.cpp +++ b/lib/CodeGen/SelectionDAG/DAGCombiner.cpp @@ -1575,6 +1575,11 @@ SDOperand DAGCombiner::visitSRA(SDNode *N) { } } + // Simplify, based on bits shifted out of the LHS. + if (N1C && SimplifyDemandedBits(SDOperand(N, 0))) + return SDOperand(N, 0); + + // If the sign bit is known to be zero, switch this to a SRL. if (TLI.MaskedValueIsZero(N0, MVT::getIntVTSignBit(VT))) return DAG.getNode(ISD::SRL, VT, N0, N1); |