From f2617291e31bc93d3dae2c80d45df5dfb9a70ae5 Mon Sep 17 00:00:00 2001 From: Robert Lytton Date: Thu, 1 Aug 2013 08:18:55 +0000 Subject: XCore target: Add byval handling git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@187563 91177308-0d34-0410-b5e6-96231b3b80d8 --- lib/Target/XCore/XCoreISelLowering.cpp | 74 +++++++++++++++++++++++++++++----- 1 file changed, 63 insertions(+), 11 deletions(-) (limited to 'lib/Target/XCore') diff --git a/lib/Target/XCore/XCoreISelLowering.cpp b/lib/Target/XCore/XCoreISelLowering.cpp index 21add4de33..1d75a2849e 100644 --- a/lib/Target/XCore/XCoreISelLowering.cpp +++ b/lib/Target/XCore/XCoreISelLowering.cpp @@ -1031,6 +1031,10 @@ XCoreTargetLowering::LowerCallResult(SDValue Chain, SDValue InFlag, // Formal Arguments Calling Convention Implementation //===----------------------------------------------------------------------===// +namespace { + struct ArgDataPair { SDValue SDV; ISD::ArgFlagsTy Flags; }; +} + /// XCore formal arguments implementation SDValue XCoreTargetLowering::LowerFormalArguments(SDValue Chain, @@ -1080,11 +1084,22 @@ XCoreTargetLowering::LowerCCCArguments(SDValue Chain, unsigned LRSaveSize = StackSlotSize; - // TODO: need to make copies of any byVal arguments - + // All getCopyFromReg ops must precede any getMemcpys to prevent the + // scheduler clobbering a register before it has been copied. + // The stages are: + // 1. CopyFromReg (and load) arg & vararg registers. + // 2. Chain CopyFromReg nodes into a TokenFactor. + // 3. Memcpy 'byVal' args & push final InVals. + // 4. Chain mem ops nodes into a TokenFactor. + SmallVector CFRegNode; + SmallVector ArgData; + SmallVector MemOps; + + // 1a. CopyFromReg (and load) arg registers. for (unsigned i = 0, e = ArgLocs.size(); i != e; ++i) { CCValAssign &VA = ArgLocs[i]; + SDValue ArgIn; if (VA.isRegLoc()) { // Arguments passed in registers @@ -1101,7 +1116,8 @@ XCoreTargetLowering::LowerCCCArguments(SDValue Chain, case MVT::i32: unsigned VReg = RegInfo.createVirtualRegister(&XCore::GRRegsRegClass); RegInfo.addLiveIn(VA.getLocReg(), VReg); - InVals.push_back(DAG.getCopyFromReg(Chain, dl, VReg, RegVT)); + ArgIn = DAG.getCopyFromReg(Chain, dl, VReg, RegVT); + CFRegNode.push_back(ArgIn.getValue(ArgIn->getNumValues() - 1)); } } else { // sanity check @@ -1121,14 +1137,17 @@ XCoreTargetLowering::LowerCCCArguments(SDValue Chain, // Create the SelectionDAG nodes corresponding to a load //from this parameter SDValue FIN = DAG.getFrameIndex(FI, MVT::i32); - InVals.push_back(DAG.getLoad(VA.getLocVT(), dl, Chain, FIN, - MachinePointerInfo::getFixedStack(FI), - false, false, false, 0)); + ArgIn = DAG.getLoad(VA.getLocVT(), dl, Chain, FIN, + MachinePointerInfo::getFixedStack(FI), + false, false, false, 0); } + const ArgDataPair ADP = { ArgIn, Ins[i].Flags }; + ArgData.push_back(ADP); } + // 1b. CopyFromReg vararg registers. if (isVarArg) { - /* Argument registers */ + // Argument registers static const uint16_t ArgRegs[] = { XCore::R0, XCore::R1, XCore::R2, XCore::R3 }; @@ -1136,7 +1155,6 @@ XCoreTargetLowering::LowerCCCArguments(SDValue Chain, unsigned FirstVAReg = CCInfo.getFirstUnallocated(ArgRegs, array_lengthof(ArgRegs)); if (FirstVAReg < array_lengthof(ArgRegs)) { - SmallVector MemOps; int offset = 0; // Save remaining registers, storing higher register numbers at a higher // address @@ -1152,14 +1170,12 @@ XCoreTargetLowering::LowerCCCArguments(SDValue Chain, unsigned VReg = RegInfo.createVirtualRegister(&XCore::GRRegsRegClass); RegInfo.addLiveIn(ArgRegs[i], VReg); SDValue Val = DAG.getCopyFromReg(Chain, dl, VReg, MVT::i32); + CFRegNode.push_back(Val.getValue(Val->getNumValues() - 1)); // Move argument from virt reg -> stack SDValue Store = DAG.getStore(Val.getValue(1), dl, Val, FIN, MachinePointerInfo(), false, false, 0); MemOps.push_back(Store); } - if (!MemOps.empty()) - Chain = DAG.getNode(ISD::TokenFactor, dl, MVT::Other, - &MemOps[0], MemOps.size()); } else { // This will point to the next argument passed via stack. XFI->setVarArgsFrameIndex( @@ -1168,6 +1184,42 @@ XCoreTargetLowering::LowerCCCArguments(SDValue Chain, } } + // 2. chain CopyFromReg nodes into a TokenFactor. + if (!CFRegNode.empty()) + Chain = DAG.getNode(ISD::TokenFactor, dl, MVT::Other, &CFRegNode[0], + CFRegNode.size()); + + // 3. Memcpy 'byVal' args & push final InVals. + // Aggregates passed "byVal" need to be copied by the callee. + // The callee will use a pointer to this copy, rather than the original + // pointer. + for (SmallVectorImpl::const_iterator ArgDI = ArgData.begin(), + ArgDE = ArgData.end(); + ArgDI != ArgDE; ++ArgDI) { + if (ArgDI->Flags.isByVal() && ArgDI->Flags.getByValSize()) { + unsigned Size = ArgDI->Flags.getByValSize(); + unsigned Align = ArgDI->Flags.getByValAlign(); + // Create a new object on the stack and copy the pointee into it. + int FI = MFI->CreateStackObject(Size, Align, false, false); + SDValue FIN = DAG.getFrameIndex(FI, MVT::i32); + InVals.push_back(FIN); + MemOps.push_back(DAG.getMemcpy(Chain, dl, FIN, ArgDI->SDV, + DAG.getConstant(Size, MVT::i32), + Align, false, false, + MachinePointerInfo(), + MachinePointerInfo())); + } else { + InVals.push_back(ArgDI->SDV); + } + } + + // 4, chain mem ops nodes into a TokenFactor. + if (!MemOps.empty()) { + MemOps.push_back(Chain); + Chain = DAG.getNode(ISD::TokenFactor, dl, MVT::Other, &MemOps[0], + MemOps.size()); + } + return Chain; } -- cgit v1.2.3