diff options
Diffstat (limited to 'llvm/lib/CodeGen')
-rw-r--r-- | llvm/lib/CodeGen/SelectionDAG/DAGCombiner.cpp | 16 |
1 files changed, 13 insertions, 3 deletions
diff --git a/llvm/lib/CodeGen/SelectionDAG/DAGCombiner.cpp b/llvm/lib/CodeGen/SelectionDAG/DAGCombiner.cpp index 3902d4ec969..2b169b755fe 100644 --- a/llvm/lib/CodeGen/SelectionDAG/DAGCombiner.cpp +++ b/llvm/lib/CodeGen/SelectionDAG/DAGCombiner.cpp @@ -11514,9 +11514,10 @@ SDValue DAGCombiner::visitCONCAT_VECTORS(SDNode *N) { if (ISD::allOperandsUndef(N)) return DAG.getUNDEF(VT); - // Optimize concat_vectors where one of the vectors is undef. - if (N->getNumOperands() == 2 && - N->getOperand(1)->getOpcode() == ISD::UNDEF) { + // Optimize concat_vectors where all but the first of the vectors are undef. + if (std::all_of(std::next(N->op_begin()), N->op_end(), [](const SDValue &Op) { + return Op.getOpcode() == ISD::UNDEF; + })) { SDValue In = N->getOperand(0); assert(In.getValueType().isVector() && "Must concat vectors"); @@ -11524,6 +11525,15 @@ SDValue DAGCombiner::visitCONCAT_VECTORS(SDNode *N) { if (In->getOpcode() == ISD::BITCAST && !In->getOperand(0)->getValueType(0).isVector()) { SDValue Scalar = In->getOperand(0); + + // If the bitcast type isn't legal, it might be a trunc of a legal type; + // look through the trunc so we can still do the transform: + // concat_vectors(trunc(scalar), undef) -> scalar_to_vector(scalar) + if (Scalar->getOpcode() == ISD::TRUNCATE && + !TLI.isTypeLegal(Scalar.getValueType()) && + TLI.isTypeLegal(Scalar->getOperand(0).getValueType())) + Scalar = Scalar->getOperand(0); + EVT SclTy = Scalar->getValueType(0); if (!SclTy.isFloatingPoint() && !SclTy.isInteger()) |