From 011381d48b1a5d2bd85c54b697f902f958c181c2 Mon Sep 17 00:00:00 2001 From: Simon Pilgrim Date: Sat, 13 Jun 2015 14:08:15 +0000 Subject: [DAGCombiner] Added BSWAP vector constant folding support. llvm-svn: 239675 --- llvm/lib/CodeGen/SelectionDAG/DAGCombiner.cpp | 12 ++++++++++++ 1 file changed, 12 insertions(+) (limited to 'llvm/lib/CodeGen/SelectionDAG/DAGCombiner.cpp') diff --git a/llvm/lib/CodeGen/SelectionDAG/DAGCombiner.cpp b/llvm/lib/CodeGen/SelectionDAG/DAGCombiner.cpp index 35943351665..1e33f1ed10f 100644 --- a/llvm/lib/CodeGen/SelectionDAG/DAGCombiner.cpp +++ b/llvm/lib/CodeGen/SelectionDAG/DAGCombiner.cpp @@ -255,6 +255,7 @@ namespace { SDValue visitSRA(SDNode *N); SDValue visitSRL(SDNode *N); SDValue visitRotate(SDNode *N); + SDValue visitBSWAP(SDNode *N); SDValue visitCTLZ(SDNode *N); SDValue visitCTLZ_ZERO_UNDEF(SDNode *N); SDValue visitCTTZ(SDNode *N); @@ -1335,6 +1336,7 @@ SDValue DAGCombiner::visit(SDNode *N) { case ISD::SRL: return visitSRL(N); case ISD::ROTR: case ISD::ROTL: return visitRotate(N); + case ISD::BSWAP: return visitBSWAP(N); case ISD::CTLZ: return visitCTLZ(N); case ISD::CTLZ_ZERO_UNDEF: return visitCTLZ_ZERO_UNDEF(N); case ISD::CTTZ: return visitCTTZ(N); @@ -4764,6 +4766,16 @@ SDValue DAGCombiner::visitSRL(SDNode *N) { return SDValue(); } +SDValue DAGCombiner::visitBSWAP(SDNode *N) { + SDValue N0 = N->getOperand(0); + EVT VT = N->getValueType(0); + + // fold (bswap c1) -> c2 + if (isConstantIntBuildVectorOrConstantInt(N0)) + return DAG.getNode(ISD::BSWAP, SDLoc(N), VT, N0); + return SDValue(); +} + SDValue DAGCombiner::visitCTLZ(SDNode *N) { SDValue N0 = N->getOperand(0); EVT VT = N->getValueType(0); -- cgit v1.2.3