diff options
Diffstat (limited to 'llvm/lib/CodeGen')
| -rw-r--r-- | llvm/lib/CodeGen/SelectionDAG/DAGCombiner.cpp | 9 |
1 files changed, 9 insertions, 0 deletions
diff --git a/llvm/lib/CodeGen/SelectionDAG/DAGCombiner.cpp b/llvm/lib/CodeGen/SelectionDAG/DAGCombiner.cpp index 8bcdda4e00a..2d2bd94eee0 100644 --- a/llvm/lib/CodeGen/SelectionDAG/DAGCombiner.cpp +++ b/llvm/lib/CodeGen/SelectionDAG/DAGCombiner.cpp @@ -17687,6 +17687,15 @@ SDValue DAGCombiner::visitCONCAT_VECTORS(SDNode *N) { SDValue In = N->getOperand(0); assert(In.getValueType().isVector() && "Must concat vectors"); + // If the input is a concat_vectors, just make a larger concat by padding + // with smaller undefs. + if (In.getOpcode() == ISD::CONCAT_VECTORS && In.hasOneUse()) { + unsigned NumOps = N->getNumOperands() * In.getNumOperands(); + SmallVector<SDValue, 4> Ops(In->op_begin(), In->op_end()); + Ops.resize(NumOps, DAG.getUNDEF(Ops[0].getValueType())); + return DAG.getNode(ISD::CONCAT_VECTORS, SDLoc(N), VT, Ops); + } + SDValue Scalar = peekThroughOneUseBitcasts(In); // concat_vectors(scalar_to_vector(scalar), undef) -> |
