static void replaceFrameIndexes(MachineFunction &MF,
SmallVector<std::pair<int,int64_t>, 16> &FR) {
MachineFrameInfo *MFI = MF.getFrameInfo();
MBlazeFunctionInfo *MBlazeFI = MF.getInfo<MBlazeFunctionInfo>();
const SmallVector<std::pair<int,int64_t>, 16>::iterator FRB = FR.begin();
const SmallVector<std::pair<int,int64_t>, 16>::iterator FRE = FR.end();
SmallVector<std::pair<int,int64_t>, 16>::iterator FRI = FRB;
for (; FRI != FRE; ++FRI) {
MFI->RemoveStackObject(FRI->first);
int NFI = MFI->CreateFixedObject(4, FRI->second, true);
MBlazeFI->recordReplacement(FRI->first, NFI);
for (MachineFunction::iterator MB=MF.begin(), ME=MF.end(); MB!=ME; ++MB) {
MachineBasicBlock::iterator MBB = MB->begin();
const MachineBasicBlock::iterator MBE = MB->end();
for (; MBB != MBE; ++MBB) {
MachineInstr::mop_iterator MIB = MBB->operands_begin();
const MachineInstr::mop_iterator MIE = MBB->operands_end();
for (MachineInstr::mop_iterator MII = MIB; MII != MIE; ++MII) {
if (!MII->isFI() || MII->getIndex() != FRI->first) continue;
DEBUG(dbgs() << "FOUND FI#" << MII->getIndex() << "\n");
MII->setIndex(NFI);
}
}
}
}
}
static void determineFrameLayout(MachineFunction &MF) {
MachineFrameInfo *MFI = MF.getFrameInfo();
MBlazeFunctionInfo *MBlazeFI = MF.getInfo<MBlazeFunctionInfo>();
// Replace the dummy '0' SPOffset by the negative offsets, as explained on
// LowerFORMAL_ARGUMENTS. Leaving '0' for while is necessary to avoid
// the approach done by calculateFrameObjectOffsets to the stack frame.
MBlazeFI->adjustLoadArgsFI(MFI);
MBlazeFI->adjustStoreVarArgsFI(MFI);
// Get the number of bytes to allocate from the FrameInfo
unsigned FrameSize = MFI->getStackSize();
DEBUG(dbgs() << "Original Frame Size: " << FrameSize << "\n" );
// Get the alignments provided by the target, and the maximum alignment
// (if any) of the fixed frame objects.
// unsigned MaxAlign = MFI->getMaxAlignment();
unsigned TargetAlign = MF.getTarget().getFrameLowering()->getStackAlignment();
unsigned AlignMask = TargetAlign - 1;
// Make sure the frame is aligned.
FrameSize = (FrameSize + AlignMask) & ~AlignMask;
MFI->setStackSize(FrameSize);
DEBUG(dbgs() << "Aligned Frame Size: " << FrameSize << "\n" );
}
void MBlazeRegisterInfo::
processFunctionBeforeFrameFinalized(MachineFunction &MF) const {
// Set the stack offset where GP must be saved/loaded from.
MachineFrameInfo *MFI = MF.getFrameInfo();
MBlazeFunctionInfo *MBlazeFI = MF.getInfo<MBlazeFunctionInfo>();
if (MBlazeFI->needGPSaveRestore())
MFI->setObjectOffset(MBlazeFI->getGPFI(), MBlazeFI->getGPStackOffset());
}
void MBlazeFrameInfo::processFunctionBeforeCalleeSavedScan(MachineFunction &MF, RegScavenger *RS)
const {
MachineFrameInfo *MFI = MF.getFrameInfo();
MBlazeFunctionInfo *MBlazeFI = MF.getInfo<MBlazeFunctionInfo>();
if (MFI->adjustsStack()) {
MBlazeFI->setRAStackOffset(0);
MFI->CreateFixedObject(4,0,true);
}
if (hasFP(MF)) {
MBlazeFI->setFPStackOffset(4);
MFI->CreateFixedObject(4,4,true);
}
}
SDValue MBlazeTargetLowering::LowerVASTART(SDValue Op,
SelectionDAG &DAG) const {
MachineFunction &MF = DAG.getMachineFunction();
MBlazeFunctionInfo *FuncInfo = MF.getInfo<MBlazeFunctionInfo>();
DebugLoc dl = Op.getDebugLoc();
SDValue FI = DAG.getFrameIndex(FuncInfo->getVarArgsFrameIndex(),
getPointerTy());
// vastart just stores the address of the VarArgsFrameIndex slot into the
// memory location argument.
const Value *SV = cast<SrcValueSDNode>(Op.getOperand(2))->getValue();
return DAG.getStore(Op.getOperand(0), dl, FI, Op.getOperand(1),
MachinePointerInfo(SV),
false, false, 0);
}
void MBlazeFrameLowering::emitPrologue(MachineFunction &MF) const {
MachineBasicBlock &MBB = MF.front();
MachineFrameInfo *MFI = MF.getFrameInfo();
const MBlazeInstrInfo &TII =
*static_cast<const MBlazeInstrInfo*>(MF.getTarget().getInstrInfo());
MBlazeFunctionInfo *MBlazeFI = MF.getInfo<MBlazeFunctionInfo>();
MachineBasicBlock::iterator MBBI = MBB.begin();
DebugLoc DL = MBBI != MBB.end() ? MBBI->getDebugLoc() : DebugLoc();
llvm::CallingConv::ID CallConv = MF.getFunction()->getCallingConv();
bool requiresRA = CallConv == llvm::CallingConv::MBLAZE_INTR;
// Determine the correct frame layout
determineFrameLayout(MF);
// Get the number of bytes to allocate from the FrameInfo.
unsigned StackSize = MFI->getStackSize();
// No need to allocate space on the stack.
if (StackSize == 0 && !MFI->adjustsStack() && !requiresRA) return;
int FPOffset = MBlazeFI->getFPStackOffset();
int RAOffset = MBlazeFI->getRAStackOffset();
// Adjust stack : addi R1, R1, -imm
BuildMI(MBB, MBBI, DL, TII.get(MBlaze::ADDIK), MBlaze::R1)
.addReg(MBlaze::R1).addImm(-StackSize);
// swi R15, R1, stack_loc
if (MFI->adjustsStack() || requiresRA) {
BuildMI(MBB, MBBI, DL, TII.get(MBlaze::SWI))
.addReg(MBlaze::R15).addReg(MBlaze::R1).addImm(RAOffset);
}
if (hasFP(MF)) {
// swi R19, R1, stack_loc
BuildMI(MBB, MBBI, DL, TII.get(MBlaze::SWI))
.addReg(MBlaze::R19).addReg(MBlaze::R1).addImm(FPOffset);
// add R19, R1, R0
BuildMI(MBB, MBBI, DL, TII.get(MBlaze::ADD), MBlaze::R19)
.addReg(MBlaze::R1).addReg(MBlaze::R0);
}
}
void MBlazeFrameInfo::emitPrologue(MachineFunction &MF) const {
MachineBasicBlock &MBB = MF.front();
MachineFrameInfo *MFI = MF.getFrameInfo();
const MBlazeInstrInfo &TII =
*static_cast<const MBlazeInstrInfo*>(MF.getTarget().getInstrInfo());
MBlazeFunctionInfo *MBlazeFI = MF.getInfo<MBlazeFunctionInfo>();
MachineBasicBlock::iterator MBBI = MBB.begin();
DebugLoc DL = MBBI != MBB.end() ? MBBI->getDebugLoc() : DebugLoc();
// Replace the dummy '0' SPOffset by the negative offsets, as explained on
// LowerFORMAL_ARGUMENTS. Leaving '0' for while is necessary to avoid
// the approach done by calculateFrameObjectOffsets to the stack frame.
MBlazeFI->adjustLoadArgsFI(MFI);
MBlazeFI->adjustStoreVarArgsFI(MFI);
// Get the number of bytes to allocate from the FrameInfo.
unsigned StackSize = MFI->getStackSize();
// No need to allocate space on the stack.
if (StackSize == 0 && !MFI->adjustsStack()) return;
int FPOffset = MBlazeFI->getFPStackOffset();
int RAOffset = MBlazeFI->getRAStackOffset();
// Adjust stack : addi R1, R1, -imm
BuildMI(MBB, MBBI, DL, TII.get(MBlaze::ADDI), MBlaze::R1)
.addReg(MBlaze::R1).addImm(-StackSize);
// swi R15, R1, stack_loc
if (MFI->adjustsStack()) {
BuildMI(MBB, MBBI, DL, TII.get(MBlaze::SWI))
.addReg(MBlaze::R15).addReg(MBlaze::R1).addImm(RAOffset);
}
if (hasFP(MF)) {
// swi R19, R1, stack_loc
BuildMI(MBB, MBBI, DL, TII.get(MBlaze::SWI))
.addReg(MBlaze::R19).addReg(MBlaze::R1).addImm(FPOffset);
// add R19, R1, R0
BuildMI(MBB, MBBI, DL, TII.get(MBlaze::ADD), MBlaze::R19)
.addReg(MBlaze::R1).addReg(MBlaze::R0);
}
}
void MBlazeFrameLowering::emitEpilogue(MachineFunction &MF,
MachineBasicBlock &MBB) const {
MachineBasicBlock::iterator MBBI = MBB.getLastNonDebugInstr();
MachineFrameInfo *MFI = MF.getFrameInfo();
MBlazeFunctionInfo *MBlazeFI = MF.getInfo<MBlazeFunctionInfo>();
const MBlazeInstrInfo &TII =
*static_cast<const MBlazeInstrInfo*>(MF.getTarget().getInstrInfo());
DebugLoc dl = MBBI->getDebugLoc();
llvm::CallingConv::ID CallConv = MF.getFunction()->getCallingConv();
bool requiresRA = CallConv == llvm::CallingConv::MBLAZE_INTR;
// Get the FI's where RA and FP are saved.
int FPOffset = MBlazeFI->getFPStackOffset();
int RAOffset = MBlazeFI->getRAStackOffset();
if (hasFP(MF)) {
// add R1, R19, R0
BuildMI(MBB, MBBI, dl, TII.get(MBlaze::ADD), MBlaze::R1)
.addReg(MBlaze::R19).addReg(MBlaze::R0);
// lwi R19, R1, stack_loc
BuildMI(MBB, MBBI, dl, TII.get(MBlaze::LWI), MBlaze::R19)
.addReg(MBlaze::R1).addImm(FPOffset);
}
// lwi R15, R1, stack_loc
if (MFI->adjustsStack() || requiresRA) {
BuildMI(MBB, MBBI, dl, TII.get(MBlaze::LWI), MBlaze::R15)
.addReg(MBlaze::R1).addImm(RAOffset);
}
// Get the number of bytes from FrameInfo
int StackSize = (int) MFI->getStackSize();
// addi R1, R1, imm
if (StackSize) {
BuildMI(MBB, MBBI, dl, TII.get(MBlaze::ADDIK), MBlaze::R1)
.addReg(MBlaze::R1).addImm(StackSize);
}
}
/// getGlobalBaseReg - Return a virtual register initialized with the
/// the global base register value. Output instructions required to
/// initialize the register in the function entry block, if necessary.
///
unsigned MBlazeInstrInfo::getGlobalBaseReg(MachineFunction *MF) const {
MBlazeFunctionInfo *MBlazeFI = MF->getInfo<MBlazeFunctionInfo>();
unsigned GlobalBaseReg = MBlazeFI->getGlobalBaseReg();
if (GlobalBaseReg != 0)
return GlobalBaseReg;
// Insert the set of GlobalBaseReg into the first MBB of the function
MachineBasicBlock &FirstMBB = MF->front();
MachineBasicBlock::iterator MBBI = FirstMBB.begin();
MachineRegisterInfo &RegInfo = MF->getRegInfo();
const TargetInstrInfo *TII = MF->getTarget().getInstrInfo();
GlobalBaseReg = RegInfo.createVirtualRegister(MBlaze::GPRRegisterClass);
BuildMI(FirstMBB, MBBI, DebugLoc(), TII->get(TargetOpcode::COPY),
GlobalBaseReg).addReg(MBlaze::R20);
RegInfo.addLiveIn(MBlaze::R20);
MBlazeFI->setGlobalBaseReg(GlobalBaseReg);
return GlobalBaseReg;
}
void MBlazeFrameLowering::
processFunctionBeforeCalleeSavedScan(MachineFunction &MF,
RegScavenger *RS) const {
MachineFrameInfo *MFI = MF.getFrameInfo();
MBlazeFunctionInfo *MBlazeFI = MF.getInfo<MBlazeFunctionInfo>();
llvm::CallingConv::ID CallConv = MF.getFunction()->getCallingConv();
bool requiresRA = CallConv == llvm::CallingConv::MBLAZE_INTR;
if (MFI->adjustsStack() || requiresRA) {
MBlazeFI->setRAStackOffset(0);
MFI->CreateFixedObject(4,0,true);
}
if (hasFP(MF)) {
MBlazeFI->setFPStackOffset(4);
MFI->CreateFixedObject(4,4,true);
}
interruptFrameLayout(MF);
analyzeFrameIndexes(MF);
}
void MBlazeFrameInfo::emitEpilogue(MachineFunction &MF,
MachineBasicBlock &MBB) const {
MachineBasicBlock::iterator MBBI = prior(MBB.end());
MachineFrameInfo *MFI = MF.getFrameInfo();
MBlazeFunctionInfo *MBlazeFI = MF.getInfo<MBlazeFunctionInfo>();
const MBlazeInstrInfo &TII =
*static_cast<const MBlazeInstrInfo*>(MF.getTarget().getInstrInfo());
DebugLoc dl = MBBI->getDebugLoc();
// Get the FI's where RA and FP are saved.
int FPOffset = MBlazeFI->getFPStackOffset();
int RAOffset = MBlazeFI->getRAStackOffset();
if (hasFP(MF)) {
// add R1, R19, R0
BuildMI(MBB, MBBI, dl, TII.get(MBlaze::ADD), MBlaze::R1)
.addReg(MBlaze::R19).addReg(MBlaze::R0);
// lwi R19, R1, stack_loc
BuildMI(MBB, MBBI, dl, TII.get(MBlaze::LWI), MBlaze::R19)
.addReg(MBlaze::R1).addImm(FPOffset);
}
// lwi R15, R1, stack_loc
if (MFI->adjustsStack()) {
BuildMI(MBB, MBBI, dl, TII.get(MBlaze::LWI), MBlaze::R15)
.addReg(MBlaze::R1).addImm(RAOffset);
}
// Get the number of bytes from FrameInfo
int StackSize = (int) MFI->getStackSize();
// addi R1, R1, imm
if (StackSize) {
BuildMI(MBB, MBBI, dl, TII.get(MBlaze::ADDI), MBlaze::R1)
.addReg(MBlaze::R1).addImm(StackSize);
}
}
/// getGlobalBaseReg - Return a virtual register initialized with the
/// the global base register value. Output instructions required to
/// initialize the register in the function entry block, if necessary.
///
unsigned MBlazeInstrInfo::getGlobalBaseReg(MachineFunction *MF) const {
MBlazeFunctionInfo *MBlazeFI = MF->getInfo<MBlazeFunctionInfo>();
unsigned GlobalBaseReg = MBlazeFI->getGlobalBaseReg();
if (GlobalBaseReg != 0)
return GlobalBaseReg;
// Insert the set of GlobalBaseReg into the first MBB of the function
MachineBasicBlock &FirstMBB = MF->front();
MachineBasicBlock::iterator MBBI = FirstMBB.begin();
MachineRegisterInfo &RegInfo = MF->getRegInfo();
const TargetInstrInfo *TII = MF->getTarget().getInstrInfo();
GlobalBaseReg = RegInfo.createVirtualRegister(MBlaze::CPURegsRegisterClass);
bool Ok = TII->copyRegToReg(FirstMBB, MBBI, GlobalBaseReg, MBlaze::R20,
MBlaze::CPURegsRegisterClass,
MBlaze::CPURegsRegisterClass,
DebugLoc());
assert(Ok && "Couldn't assign to global base register!");
Ok = Ok; // Silence warning when assertions are turned off.
RegInfo.addLiveIn(MBlaze::R20);
MBlazeFI->setGlobalBaseReg(GlobalBaseReg);
return GlobalBaseReg;
}
static void analyzeFrameIndexes(MachineFunction &MF) {
if (MBDisableStackAdjust) return;
MachineFrameInfo *MFI = MF.getFrameInfo();
MBlazeFunctionInfo *MBlazeFI = MF.getInfo<MBlazeFunctionInfo>();
const MachineRegisterInfo &MRI = MF.getRegInfo();
MachineRegisterInfo::livein_iterator LII = MRI.livein_begin();
MachineRegisterInfo::livein_iterator LIE = MRI.livein_end();
const SmallVector<int, 16> &LiveInFI = MBlazeFI->getLiveIn();
SmallVector<MachineInstr*, 16> EraseInstr;
SmallVector<std::pair<int,int64_t>, 16> FrameRelocate;
MachineBasicBlock *MBB = MF.getBlockNumbered(0);
MachineBasicBlock::iterator MIB = MBB->begin();
MachineBasicBlock::iterator MIE = MBB->end();
int StackAdjust = 0;
int StackOffset = -28;
// In this loop we are searching frame indexes that corrospond to incoming
// arguments that are already in the stack. We look for instruction sequences
// like the following:
//
// LWI REG, FI1, 0
// ...
// SWI REG, FI2, 0
//
// As long as there are no defs of REG in the ... part, we can eliminate
// the SWI instruction because the value has already been stored to the
// stack by the caller. All we need to do is locate FI at the correct
// stack location according to the calling convensions.
//
// Additionally, if the SWI operation kills the def of REG then we don't
// need the LWI operation so we can erase it as well.
for (unsigned i = 0, e = LiveInFI.size(); i < e; ++i) {
for (MachineBasicBlock::iterator I=MIB; I != MIE; ++I) {
if (I->getOpcode() != MBlaze::LWI || I->getNumOperands() != 3 ||
!I->getOperand(1).isFI() || !I->getOperand(0).isReg() ||
I->getOperand(1).getIndex() != LiveInFI[i]) continue;
unsigned FIReg = I->getOperand(0).getReg();
MachineBasicBlock::iterator SI = I;
for (SI++; SI != MIE; ++SI) {
if (!SI->getOperand(0).isReg() ||
!SI->getOperand(1).isFI() ||
SI->getOpcode() != MBlaze::SWI) continue;
int FI = SI->getOperand(1).getIndex();
if (SI->getOperand(0).getReg() != FIReg ||
MFI->isFixedObjectIndex(FI) ||
MFI->getObjectSize(FI) != 4) continue;
if (SI->getOperand(0).isDef()) break;
if (SI->getOperand(0).isKill()) {
DEBUG(dbgs() << "LWI for FI#" << I->getOperand(1).getIndex()
<< " removed\n");
EraseInstr.push_back(I);
}
EraseInstr.push_back(SI);
DEBUG(dbgs() << "SWI for FI#" << FI << " removed\n");
FrameRelocate.push_back(std::make_pair(FI,StackOffset));
DEBUG(dbgs() << "FI#" << FI << " relocated to " << StackOffset << "\n");
StackOffset -= 4;
StackAdjust += 4;
break;
}
}
}
// In this loop we are searching for frame indexes that corrospond to
// incoming arguments that are in registers. We look for instruction
// sequences like the following:
//
// ... SWI REG, FI, 0
//
// As long as the ... part does not define REG and if REG is an incoming
// parameter register then we know that, according to ABI convensions, the
// caller has allocated stack space for it already. Instead of allocating
// stack space on our frame, we record the correct location in the callers
// frame.
for (MachineRegisterInfo::livein_iterator LI = LII; LI != LIE; ++LI) {
for (MachineBasicBlock::iterator I=MIB; I != MIE; ++I) {
if (I->definesRegister(LI->first))
break;
if (I->getOpcode() != MBlaze::SWI || I->getNumOperands() != 3 ||
!I->getOperand(1).isFI() || !I->getOperand(0).isReg() ||
I->getOperand(1).getIndex() < 0) continue;
if (I->getOperand(0).getReg() == LI->first) {
int FI = I->getOperand(1).getIndex();
MBlazeFI->recordLiveIn(FI);
int FILoc = 0;
switch (LI->first) {
default: llvm_unreachable("invalid incoming parameter!");
case MBlaze::R5: FILoc = -4; break;
case MBlaze::R6: FILoc = -8; break;
case MBlaze::R7: FILoc = -12; break;
case MBlaze::R8: FILoc = -16; break;
case MBlaze::R9: FILoc = -20; break;
case MBlaze::R10: FILoc = -24; break;
}
StackAdjust += 4;
FrameRelocate.push_back(std::make_pair(FI,FILoc));
DEBUG(dbgs() << "FI#" << FI << " relocated to " << FILoc << "\n");
break;
}
}
}
// Go ahead and erase all of the instructions that we determined were
// no longer needed.
for (int i = 0, e = EraseInstr.size(); i < e; ++i)
MBB->erase(EraseInstr[i]);
// Replace all of the frame indexes that we have relocated with new
// fixed object frame indexes.
replaceFrameIndexes(MF, FrameRelocate);
}
/// LowerFormalArguments - transform physical registers into
/// virtual registers and generate load operations for
/// arguments places on the stack.
SDValue MBlazeTargetLowering::
LowerFormalArguments(SDValue Chain, CallingConv::ID CallConv, bool isVarArg,
const SmallVectorImpl<ISD::InputArg> &Ins,
DebugLoc dl, SelectionDAG &DAG,
SmallVectorImpl<SDValue> &InVals) const {
MachineFunction &MF = DAG.getMachineFunction();
MachineFrameInfo *MFI = MF.getFrameInfo();
MBlazeFunctionInfo *MBlazeFI = MF.getInfo<MBlazeFunctionInfo>();
unsigned StackReg = MF.getTarget().getRegisterInfo()->getFrameRegister(MF);
MBlazeFI->setVarArgsFrameIndex(0);
// Used with vargs to acumulate store chains.
std::vector<SDValue> OutChains;
// Keep track of the last register used for arguments
unsigned ArgRegEnd = 0;
// Assign locations to all of the incoming arguments.
SmallVector<CCValAssign, 16> ArgLocs;
CCState CCInfo(CallConv, isVarArg, getTargetMachine(),
ArgLocs, *DAG.getContext());
CCInfo.AnalyzeFormalArguments(Ins, CC_MBlaze);
SDValue StackPtr;
for (unsigned i = 0, e = ArgLocs.size(); i != e; ++i) {
CCValAssign &VA = ArgLocs[i];
// Arguments stored on registers
if (VA.isRegLoc()) {
MVT RegVT = VA.getLocVT();
ArgRegEnd = VA.getLocReg();
TargetRegisterClass *RC = 0;
if (RegVT == MVT::i32)
RC = MBlaze::GPRRegisterClass;
else if (RegVT == MVT::f32)
RC = MBlaze::GPRRegisterClass;
else
llvm_unreachable("RegVT not supported by LowerFormalArguments");
// Transform the arguments stored on
// physical registers into virtual ones
unsigned Reg = MF.addLiveIn(ArgRegEnd, RC);
SDValue ArgValue = DAG.getCopyFromReg(Chain, dl, Reg, RegVT);
// If this is an 8 or 16-bit value, it has been passed promoted
// to 32 bits. Insert an assert[sz]ext to capture this, then
// truncate to the right size. If if is a floating point value
// then convert to the correct type.
if (VA.getLocInfo() != CCValAssign::Full) {
unsigned Opcode = 0;
if (VA.getLocInfo() == CCValAssign::SExt)
Opcode = ISD::AssertSext;
else if (VA.getLocInfo() == CCValAssign::ZExt)
Opcode = ISD::AssertZext;
if (Opcode)
ArgValue = DAG.getNode(Opcode, dl, RegVT, ArgValue,
DAG.getValueType(VA.getValVT()));
ArgValue = DAG.getNode(ISD::TRUNCATE, dl, VA.getValVT(), ArgValue);
}
InVals.push_back(ArgValue);
} else { // VA.isRegLoc()
// sanity check
assert(VA.isMemLoc());
// The last argument is not a register
ArgRegEnd = 0;
// The stack pointer offset is relative to the caller stack frame.
// Since the real stack size is unknown here, a negative SPOffset
// is used so there's a way to adjust these offsets when the stack
// size get known (on EliminateFrameIndex). A dummy SPOffset is
// used instead of a direct negative address (which is recorded to
// be used on emitPrologue) to avoid mis-calc of the first stack
// offset on PEI::calculateFrameObjectOffsets.
// Arguments are always 32-bit.
unsigned ArgSize = VA.getLocVT().getSizeInBits()/8;
unsigned StackLoc = VA.getLocMemOffset() + 4;
int FI = MFI->CreateFixedObject(ArgSize, 0, true);
MBlazeFI->recordLoadArgsFI(FI, -StackLoc);
// Create load nodes to retrieve arguments from the stack
SDValue FIN = DAG.getFrameIndex(FI, getPointerTy());
InVals.push_back(DAG.getLoad(VA.getValVT(), dl, Chain, FIN,
MachinePointerInfo::getFixedStack(FI),
false, false, 0));
}
}
// To meet ABI, when VARARGS are passed on registers, the registers
// must have their values written to the caller stack frame. If the last
// argument was placed in the stack, there's no need to save any register.
if ((isVarArg) && ArgRegEnd) {
if (StackPtr.getNode() == 0)
StackPtr = DAG.getRegister(StackReg, getPointerTy());
// The last register argument that must be saved is MBlaze::R10
TargetRegisterClass *RC = MBlaze::GPRRegisterClass;
unsigned Begin = MBlazeRegisterInfo::getRegisterNumbering(MBlaze::R5);
unsigned Start = MBlazeRegisterInfo::getRegisterNumbering(ArgRegEnd+1);
unsigned End = MBlazeRegisterInfo::getRegisterNumbering(MBlaze::R10);
unsigned StackLoc = Start - Begin + 1;
for (; Start <= End; ++Start, ++StackLoc) {
unsigned Reg = MBlazeRegisterInfo::getRegisterFromNumbering(Start);
unsigned LiveReg = MF.addLiveIn(Reg, RC);
SDValue ArgValue = DAG.getCopyFromReg(Chain, dl, LiveReg, MVT::i32);
int FI = MFI->CreateFixedObject(4, 0, true);
MBlazeFI->recordStoreVarArgsFI(FI, -(StackLoc*4));
SDValue PtrOff = DAG.getFrameIndex(FI, getPointerTy());
OutChains.push_back(DAG.getStore(Chain, dl, ArgValue, PtrOff,
MachinePointerInfo(),
false, false, 0));
// Record the frame index of the first variable argument
// which is a value necessary to VASTART.
if (!MBlazeFI->getVarArgsFrameIndex())
MBlazeFI->setVarArgsFrameIndex(FI);
}
}
// All stores are grouped in one node to allow the matching between
// the size of Ins and InVals. This only happens when on varg functions
if (!OutChains.empty()) {
OutChains.push_back(Chain);
Chain = DAG.getNode(ISD::TokenFactor, dl, MVT::Other,
&OutChains[0], OutChains.size());
}
return Chain;
}
