From bd223423220bec2ab8c4fa9506fd7c5692ef6039 Mon Sep 17 00:00:00 2001 From: Matt Arsenault Date: Wed, 14 Jan 2015 01:35:17 +0000 Subject: Implement new way of expanding extloads. Now that the source and destination types can be specified, allow doing an expansion that doesn't use an EXTLOAD of the result type. Try to do a legal extload to an intermediate type and extend that if possible. This generalizes the special case custom lowering of extloads R600 has been using to work around this problem. This also happens to fix a bug that would incorrectly use more aligned loads than should be used. llvm-svn: 225925 --- llvm/lib/CodeGen/SelectionDAG/LegalizeDAG.cpp | 31 +++++++++++++++------------ 1 file changed, 17 insertions(+), 14 deletions(-) (limited to 'llvm/lib/CodeGen/SelectionDAG/LegalizeDAG.cpp') diff --git a/llvm/lib/CodeGen/SelectionDAG/LegalizeDAG.cpp b/llvm/lib/CodeGen/SelectionDAG/LegalizeDAG.cpp index ce8f96b7605..e5473e35cae 100644 --- a/llvm/lib/CodeGen/SelectionDAG/LegalizeDAG.cpp +++ b/llvm/lib/CodeGen/SelectionDAG/LegalizeDAG.cpp @@ -1090,22 +1090,25 @@ void SelectionDAGLegalize::LegalizeLoadOps(SDNode *Node) { break; } case TargetLowering::Expand: - if (!TLI.isLoadExtLegal(ISD::EXTLOAD, Node->getValueType(0), - SrcVT) && TLI.isTypeLegal(SrcVT)) { - SDValue Load = DAG.getLoad(SrcVT, dl, Chain, Ptr, LD->getMemOperand()); - unsigned ExtendOp; - switch (ExtType) { - case ISD::EXTLOAD: - ExtendOp = (SrcVT.isFloatingPoint() ? - ISD::FP_EXTEND : ISD::ANY_EXTEND); + if (!TLI.isLoadExtLegal(ISD::EXTLOAD, Node->getValueType(0), SrcVT)) { + // If the source type is not legal, see if there is a legal extload to + // an intermediate type that we can then extend further. + EVT LoadVT = TLI.getRegisterType(SrcVT.getSimpleVT()); + if (TLI.isTypeLegal(SrcVT) || // Same as SrcVT == LoadVT? + TLI.isLoadExtLegal(ExtType, LoadVT, SrcVT)) { + // If we are loading a legal type, this is a non-extload followed by a + // full extend. + ISD::LoadExtType MidExtType = + (LoadVT == SrcVT) ? ISD::NON_EXTLOAD : ExtType; + + SDValue Load = DAG.getExtLoad(MidExtType, dl, LoadVT, Chain, Ptr, + SrcVT, LD->getMemOperand()); + unsigned ExtendOp = + ISD::getExtForLoadExtType(SrcVT.isFloatingPoint(), ExtType); + Value = DAG.getNode(ExtendOp, dl, Node->getValueType(0), Load); + Chain = Load.getValue(1); break; - case ISD::SEXTLOAD: ExtendOp = ISD::SIGN_EXTEND; break; - case ISD::ZEXTLOAD: ExtendOp = ISD::ZERO_EXTEND; break; - default: llvm_unreachable("Unexpected extend load type!"); } - Value = DAG.getNode(ExtendOp, dl, Node->getValueType(0), Load); - Chain = Load.getValue(1); - break; } assert(!SrcVT.isVector() && -- cgit v1.2.3