llvm-for-llvmta/lib/Target/Mips/MipsCallLowering.cpp

686 lines
24 KiB
C++

//===- MipsCallLowering.cpp -------------------------------------*- C++ -*-===//
//
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
// See https://llvm.org/LICENSE.txt for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
//
//===----------------------------------------------------------------------===//
//
/// \file
/// This file implements the lowering of LLVM calls to machine code calls for
/// GlobalISel.
//
//===----------------------------------------------------------------------===//
#include "MipsCallLowering.h"
#include "MipsCCState.h"
#include "MipsMachineFunction.h"
#include "MipsTargetMachine.h"
#include "llvm/CodeGen/Analysis.h"
#include "llvm/CodeGen/GlobalISel/MachineIRBuilder.h"
using namespace llvm;
MipsCallLowering::MipsCallLowering(const MipsTargetLowering &TLI)
: CallLowering(&TLI) {}
bool MipsCallLowering::MipsHandler::assign(Register VReg, const CCValAssign &VA,
const EVT &VT) {
if (VA.isRegLoc()) {
assignValueToReg(VReg, VA, VT);
} else if (VA.isMemLoc()) {
assignValueToAddress(VReg, VA);
} else {
return false;
}
return true;
}
bool MipsCallLowering::MipsHandler::assignVRegs(ArrayRef<Register> VRegs,
ArrayRef<CCValAssign> ArgLocs,
unsigned ArgLocsStartIndex,
const EVT &VT) {
for (unsigned i = 0; i < VRegs.size(); ++i)
if (!assign(VRegs[i], ArgLocs[ArgLocsStartIndex + i], VT))
return false;
return true;
}
void MipsCallLowering::MipsHandler::setLeastSignificantFirst(
SmallVectorImpl<Register> &VRegs) {
if (!MIRBuilder.getMF().getDataLayout().isLittleEndian())
std::reverse(VRegs.begin(), VRegs.end());
}
bool MipsCallLowering::MipsHandler::handle(
ArrayRef<CCValAssign> ArgLocs, ArrayRef<CallLowering::ArgInfo> Args) {
SmallVector<Register, 4> VRegs;
unsigned SplitLength;
const Function &F = MIRBuilder.getMF().getFunction();
const DataLayout &DL = F.getParent()->getDataLayout();
const MipsTargetLowering &TLI = *static_cast<const MipsTargetLowering *>(
MIRBuilder.getMF().getSubtarget().getTargetLowering());
for (unsigned ArgsIndex = 0, ArgLocsIndex = 0; ArgsIndex < Args.size();
++ArgsIndex, ArgLocsIndex += SplitLength) {
EVT VT = TLI.getValueType(DL, Args[ArgsIndex].Ty);
SplitLength = TLI.getNumRegistersForCallingConv(F.getContext(),
F.getCallingConv(), VT);
assert(Args[ArgsIndex].Regs.size() == 1 && "Can't handle multple regs yet");
if (SplitLength > 1) {
VRegs.clear();
MVT RegisterVT = TLI.getRegisterTypeForCallingConv(
F.getContext(), F.getCallingConv(), VT);
for (unsigned i = 0; i < SplitLength; ++i)
VRegs.push_back(MRI.createGenericVirtualRegister(LLT{RegisterVT}));
if (!handleSplit(VRegs, ArgLocs, ArgLocsIndex, Args[ArgsIndex].Regs[0],
VT))
return false;
} else {
if (!assign(Args[ArgsIndex].Regs[0], ArgLocs[ArgLocsIndex], VT))
return false;
}
}
return true;
}
namespace {
class MipsIncomingValueHandler : public MipsCallLowering::MipsHandler {
public:
MipsIncomingValueHandler(MachineIRBuilder &MIRBuilder,
MachineRegisterInfo &MRI)
: MipsHandler(MIRBuilder, MRI) {}
private:
void assignValueToReg(Register ValVReg, const CCValAssign &VA,
const EVT &VT) override;
Register getStackAddress(const CCValAssign &VA,
MachineMemOperand *&MMO) override;
void assignValueToAddress(Register ValVReg, const CCValAssign &VA) override;
bool handleSplit(SmallVectorImpl<Register> &VRegs,
ArrayRef<CCValAssign> ArgLocs, unsigned ArgLocsStartIndex,
Register ArgsReg, const EVT &VT) override;
virtual void markPhysRegUsed(unsigned PhysReg) {
MIRBuilder.getMRI()->addLiveIn(PhysReg);
MIRBuilder.getMBB().addLiveIn(PhysReg);
}
MachineInstrBuilder buildLoad(const DstOp &Res, const CCValAssign &VA) {
MachineMemOperand *MMO;
Register Addr = getStackAddress(VA, MMO);
return MIRBuilder.buildLoad(Res, Addr, *MMO);
}
};
class CallReturnHandler : public MipsIncomingValueHandler {
public:
CallReturnHandler(MachineIRBuilder &MIRBuilder, MachineRegisterInfo &MRI,
MachineInstrBuilder &MIB)
: MipsIncomingValueHandler(MIRBuilder, MRI), MIB(MIB) {}
private:
void markPhysRegUsed(unsigned PhysReg) override {
MIB.addDef(PhysReg, RegState::Implicit);
}
MachineInstrBuilder &MIB;
};
} // end anonymous namespace
void MipsIncomingValueHandler::assignValueToReg(Register ValVReg,
const CCValAssign &VA,
const EVT &VT) {
Register PhysReg = VA.getLocReg();
if (VT == MVT::f64 && PhysReg >= Mips::A0 && PhysReg <= Mips::A3) {
const MipsSubtarget &STI =
static_cast<const MipsSubtarget &>(MIRBuilder.getMF().getSubtarget());
bool IsEL = STI.isLittle();
LLT s32 = LLT::scalar(32);
auto Lo = MIRBuilder.buildCopy(s32, Register(PhysReg + (IsEL ? 0 : 1)));
auto Hi = MIRBuilder.buildCopy(s32, Register(PhysReg + (IsEL ? 1 : 0)));
MIRBuilder.buildMerge(ValVReg, {Lo, Hi});
markPhysRegUsed(PhysReg);
markPhysRegUsed(PhysReg + 1);
} else if (VT == MVT::f32 && PhysReg >= Mips::A0 && PhysReg <= Mips::A3) {
MIRBuilder.buildCopy(ValVReg, PhysReg);
markPhysRegUsed(PhysReg);
} else {
switch (VA.getLocInfo()) {
case CCValAssign::LocInfo::SExt:
case CCValAssign::LocInfo::ZExt:
case CCValAssign::LocInfo::AExt: {
auto Copy = MIRBuilder.buildCopy(LLT{VA.getLocVT()}, PhysReg);
MIRBuilder.buildTrunc(ValVReg, Copy);
break;
}
default:
MIRBuilder.buildCopy(ValVReg, PhysReg);
break;
}
markPhysRegUsed(PhysReg);
}
}
Register MipsIncomingValueHandler::getStackAddress(const CCValAssign &VA,
MachineMemOperand *&MMO) {
MachineFunction &MF = MIRBuilder.getMF();
unsigned Size = alignTo(VA.getValVT().getSizeInBits(), 8) / 8;
unsigned Offset = VA.getLocMemOffset();
MachineFrameInfo &MFI = MF.getFrameInfo();
int FI = MFI.CreateFixedObject(Size, Offset, true);
MachinePointerInfo MPO =
MachinePointerInfo::getFixedStack(MIRBuilder.getMF(), FI);
const TargetFrameLowering *TFL = MF.getSubtarget().getFrameLowering();
Align Alignment = commonAlignment(TFL->getStackAlign(), Offset);
MMO =
MF.getMachineMemOperand(MPO, MachineMemOperand::MOLoad, Size, Alignment);
return MIRBuilder.buildFrameIndex(LLT::pointer(0, 32), FI).getReg(0);
}
void MipsIncomingValueHandler::assignValueToAddress(Register ValVReg,
const CCValAssign &VA) {
if (VA.getLocInfo() == CCValAssign::SExt ||
VA.getLocInfo() == CCValAssign::ZExt ||
VA.getLocInfo() == CCValAssign::AExt) {
auto Load = buildLoad(LLT::scalar(32), VA);
MIRBuilder.buildTrunc(ValVReg, Load);
} else
buildLoad(ValVReg, VA);
}
bool MipsIncomingValueHandler::handleSplit(SmallVectorImpl<Register> &VRegs,
ArrayRef<CCValAssign> ArgLocs,
unsigned ArgLocsStartIndex,
Register ArgsReg, const EVT &VT) {
if (!assignVRegs(VRegs, ArgLocs, ArgLocsStartIndex, VT))
return false;
setLeastSignificantFirst(VRegs);
MIRBuilder.buildMerge(ArgsReg, VRegs);
return true;
}
namespace {
class MipsOutgoingValueHandler : public MipsCallLowering::MipsHandler {
public:
MipsOutgoingValueHandler(MachineIRBuilder &MIRBuilder,
MachineRegisterInfo &MRI, MachineInstrBuilder &MIB)
: MipsHandler(MIRBuilder, MRI), MIB(MIB) {}
private:
void assignValueToReg(Register ValVReg, const CCValAssign &VA,
const EVT &VT) override;
Register getStackAddress(const CCValAssign &VA,
MachineMemOperand *&MMO) override;
void assignValueToAddress(Register ValVReg, const CCValAssign &VA) override;
bool handleSplit(SmallVectorImpl<Register> &VRegs,
ArrayRef<CCValAssign> ArgLocs, unsigned ArgLocsStartIndex,
Register ArgsReg, const EVT &VT) override;
Register extendRegister(Register ValReg, const CCValAssign &VA);
MachineInstrBuilder &MIB;
};
} // end anonymous namespace
void MipsOutgoingValueHandler::assignValueToReg(Register ValVReg,
const CCValAssign &VA,
const EVT &VT) {
Register PhysReg = VA.getLocReg();
if (VT == MVT::f64 && PhysReg >= Mips::A0 && PhysReg <= Mips::A3) {
const MipsSubtarget &STI =
static_cast<const MipsSubtarget &>(MIRBuilder.getMF().getSubtarget());
bool IsEL = STI.isLittle();
auto Unmerge = MIRBuilder.buildUnmerge(LLT::scalar(32), ValVReg);
MIRBuilder.buildCopy(Register(PhysReg + (IsEL ? 0 : 1)), Unmerge.getReg(0));
MIRBuilder.buildCopy(Register(PhysReg + (IsEL ? 1 : 0)), Unmerge.getReg(1));
} else if (VT == MVT::f32 && PhysReg >= Mips::A0 && PhysReg <= Mips::A3) {
MIRBuilder.buildCopy(PhysReg, ValVReg);
} else {
Register ExtReg = extendRegister(ValVReg, VA);
MIRBuilder.buildCopy(PhysReg, ExtReg);
MIB.addUse(PhysReg, RegState::Implicit);
}
}
Register MipsOutgoingValueHandler::getStackAddress(const CCValAssign &VA,
MachineMemOperand *&MMO) {
MachineFunction &MF = MIRBuilder.getMF();
const TargetFrameLowering *TFL = MF.getSubtarget().getFrameLowering();
LLT p0 = LLT::pointer(0, 32);
LLT s32 = LLT::scalar(32);
auto SPReg = MIRBuilder.buildCopy(p0, Register(Mips::SP));
unsigned Offset = VA.getLocMemOffset();
auto OffsetReg = MIRBuilder.buildConstant(s32, Offset);
auto AddrReg = MIRBuilder.buildPtrAdd(p0, SPReg, OffsetReg);
MachinePointerInfo MPO =
MachinePointerInfo::getStack(MIRBuilder.getMF(), Offset);
unsigned Size = alignTo(VA.getValVT().getSizeInBits(), 8) / 8;
Align Alignment = commonAlignment(TFL->getStackAlign(), Offset);
MMO =
MF.getMachineMemOperand(MPO, MachineMemOperand::MOStore, Size, Alignment);
return AddrReg.getReg(0);
}
void MipsOutgoingValueHandler::assignValueToAddress(Register ValVReg,
const CCValAssign &VA) {
MachineMemOperand *MMO;
Register Addr = getStackAddress(VA, MMO);
Register ExtReg = extendRegister(ValVReg, VA);
MIRBuilder.buildStore(ExtReg, Addr, *MMO);
}
Register MipsOutgoingValueHandler::extendRegister(Register ValReg,
const CCValAssign &VA) {
LLT LocTy{VA.getLocVT()};
switch (VA.getLocInfo()) {
case CCValAssign::SExt: {
return MIRBuilder.buildSExt(LocTy, ValReg).getReg(0);
}
case CCValAssign::ZExt: {
return MIRBuilder.buildZExt(LocTy, ValReg).getReg(0);
}
case CCValAssign::AExt: {
return MIRBuilder.buildAnyExt(LocTy, ValReg).getReg(0);
}
// TODO : handle upper extends
case CCValAssign::Full:
return ValReg;
default:
break;
}
llvm_unreachable("unable to extend register");
}
bool MipsOutgoingValueHandler::handleSplit(SmallVectorImpl<Register> &VRegs,
ArrayRef<CCValAssign> ArgLocs,
unsigned ArgLocsStartIndex,
Register ArgsReg, const EVT &VT) {
MIRBuilder.buildUnmerge(VRegs, ArgsReg);
setLeastSignificantFirst(VRegs);
if (!assignVRegs(VRegs, ArgLocs, ArgLocsStartIndex, VT))
return false;
return true;
}
static bool isSupportedArgumentType(Type *T) {
if (T->isIntegerTy())
return true;
if (T->isPointerTy())
return true;
if (T->isFloatingPointTy())
return true;
return false;
}
static bool isSupportedReturnType(Type *T) {
if (T->isIntegerTy())
return true;
if (T->isPointerTy())
return true;
if (T->isFloatingPointTy())
return true;
if (T->isAggregateType())
return true;
return false;
}
static CCValAssign::LocInfo determineLocInfo(const MVT RegisterVT, const EVT VT,
const ISD::ArgFlagsTy &Flags) {
// > does not mean loss of information as type RegisterVT can't hold type VT,
// it means that type VT is split into multiple registers of type RegisterVT
if (VT.getFixedSizeInBits() >= RegisterVT.getFixedSizeInBits())
return CCValAssign::LocInfo::Full;
if (Flags.isSExt())
return CCValAssign::LocInfo::SExt;
if (Flags.isZExt())
return CCValAssign::LocInfo::ZExt;
return CCValAssign::LocInfo::AExt;
}
template <typename T>
static void setLocInfo(SmallVectorImpl<CCValAssign> &ArgLocs,
const SmallVectorImpl<T> &Arguments) {
for (unsigned i = 0; i < ArgLocs.size(); ++i) {
const CCValAssign &VA = ArgLocs[i];
CCValAssign::LocInfo LocInfo = determineLocInfo(
Arguments[i].VT, Arguments[i].ArgVT, Arguments[i].Flags);
if (VA.isMemLoc())
ArgLocs[i] =
CCValAssign::getMem(VA.getValNo(), VA.getValVT(),
VA.getLocMemOffset(), VA.getLocVT(), LocInfo);
else
ArgLocs[i] = CCValAssign::getReg(VA.getValNo(), VA.getValVT(),
VA.getLocReg(), VA.getLocVT(), LocInfo);
}
}
bool MipsCallLowering::lowerReturn(MachineIRBuilder &MIRBuilder,
const Value *Val, ArrayRef<Register> VRegs,
FunctionLoweringInfo &FLI) const {
MachineInstrBuilder Ret = MIRBuilder.buildInstrNoInsert(Mips::RetRA);
if (Val != nullptr && !isSupportedReturnType(Val->getType()))
return false;
if (!VRegs.empty()) {
MachineFunction &MF = MIRBuilder.getMF();
const Function &F = MF.getFunction();
const DataLayout &DL = MF.getDataLayout();
const MipsTargetLowering &TLI = *getTLI<MipsTargetLowering>();
SmallVector<ArgInfo, 8> RetInfos;
SmallVector<unsigned, 8> OrigArgIndices;
ArgInfo ArgRetInfo(VRegs, Val->getType());
setArgFlags(ArgRetInfo, AttributeList::ReturnIndex, DL, F);
splitToValueTypes(DL, ArgRetInfo, 0, RetInfos, OrigArgIndices);
SmallVector<ISD::OutputArg, 8> Outs;
subTargetRegTypeForCallingConv(F, RetInfos, OrigArgIndices, Outs);
SmallVector<CCValAssign, 16> ArgLocs;
MipsCCState CCInfo(F.getCallingConv(), F.isVarArg(), MF, ArgLocs,
F.getContext());
CCInfo.AnalyzeReturn(Outs, TLI.CCAssignFnForReturn());
setLocInfo(ArgLocs, Outs);
MipsOutgoingValueHandler RetHandler(MIRBuilder, MF.getRegInfo(), Ret);
if (!RetHandler.handle(ArgLocs, RetInfos)) {
return false;
}
}
MIRBuilder.insertInstr(Ret);
return true;
}
bool MipsCallLowering::lowerFormalArguments(MachineIRBuilder &MIRBuilder,
const Function &F,
ArrayRef<ArrayRef<Register>> VRegs,
FunctionLoweringInfo &FLI) const {
// Quick exit if there aren't any args.
if (F.arg_empty())
return true;
for (auto &Arg : F.args()) {
if (!isSupportedArgumentType(Arg.getType()))
return false;
}
MachineFunction &MF = MIRBuilder.getMF();
const DataLayout &DL = MF.getDataLayout();
const MipsTargetLowering &TLI = *getTLI<MipsTargetLowering>();
SmallVector<ArgInfo, 8> ArgInfos;
SmallVector<unsigned, 8> OrigArgIndices;
unsigned i = 0;
for (auto &Arg : F.args()) {
ArgInfo AInfo(VRegs[i], Arg.getType());
setArgFlags(AInfo, i + AttributeList::FirstArgIndex, DL, F);
ArgInfos.push_back(AInfo);
OrigArgIndices.push_back(i);
++i;
}
SmallVector<ISD::InputArg, 8> Ins;
subTargetRegTypeForCallingConv(F, ArgInfos, OrigArgIndices, Ins);
SmallVector<CCValAssign, 16> ArgLocs;
MipsCCState CCInfo(F.getCallingConv(), F.isVarArg(), MF, ArgLocs,
F.getContext());
const MipsTargetMachine &TM =
static_cast<const MipsTargetMachine &>(MF.getTarget());
const MipsABIInfo &ABI = TM.getABI();
CCInfo.AllocateStack(ABI.GetCalleeAllocdArgSizeInBytes(F.getCallingConv()),
Align(1));
CCInfo.AnalyzeFormalArguments(Ins, TLI.CCAssignFnForCall());
setLocInfo(ArgLocs, Ins);
MipsIncomingValueHandler Handler(MIRBuilder, MF.getRegInfo());
if (!Handler.handle(ArgLocs, ArgInfos))
return false;
if (F.isVarArg()) {
ArrayRef<MCPhysReg> ArgRegs = ABI.GetVarArgRegs();
unsigned Idx = CCInfo.getFirstUnallocated(ArgRegs);
int VaArgOffset;
unsigned RegSize = 4;
if (ArgRegs.size() == Idx)
VaArgOffset = alignTo(CCInfo.getNextStackOffset(), RegSize);
else {
VaArgOffset =
(int)ABI.GetCalleeAllocdArgSizeInBytes(CCInfo.getCallingConv()) -
(int)(RegSize * (ArgRegs.size() - Idx));
}
MachineFrameInfo &MFI = MF.getFrameInfo();
int FI = MFI.CreateFixedObject(RegSize, VaArgOffset, true);
MF.getInfo<MipsFunctionInfo>()->setVarArgsFrameIndex(FI);
for (unsigned I = Idx; I < ArgRegs.size(); ++I, VaArgOffset += RegSize) {
MIRBuilder.getMBB().addLiveIn(ArgRegs[I]);
MachineInstrBuilder Copy =
MIRBuilder.buildCopy(LLT::scalar(RegSize * 8), Register(ArgRegs[I]));
FI = MFI.CreateFixedObject(RegSize, VaArgOffset, true);
MachinePointerInfo MPO = MachinePointerInfo::getFixedStack(MF, FI);
MachineInstrBuilder FrameIndex =
MIRBuilder.buildFrameIndex(LLT::pointer(MPO.getAddrSpace(), 32), FI);
MachineMemOperand *MMO = MF.getMachineMemOperand(
MPO, MachineMemOperand::MOStore, RegSize, Align(RegSize));
MIRBuilder.buildStore(Copy, FrameIndex, *MMO);
}
}
return true;
}
bool MipsCallLowering::lowerCall(MachineIRBuilder &MIRBuilder,
CallLoweringInfo &Info) const {
if (Info.CallConv != CallingConv::C)
return false;
for (auto &Arg : Info.OrigArgs) {
if (!isSupportedArgumentType(Arg.Ty))
return false;
if (Arg.Flags[0].isByVal())
return false;
if (Arg.Flags[0].isSRet() && !Arg.Ty->isPointerTy())
return false;
}
if (!Info.OrigRet.Ty->isVoidTy() && !isSupportedReturnType(Info.OrigRet.Ty))
return false;
MachineFunction &MF = MIRBuilder.getMF();
const Function &F = MF.getFunction();
const DataLayout &DL = MF.getDataLayout();
const MipsTargetLowering &TLI = *getTLI<MipsTargetLowering>();
const MipsTargetMachine &TM =
static_cast<const MipsTargetMachine &>(MF.getTarget());
const MipsABIInfo &ABI = TM.getABI();
MachineInstrBuilder CallSeqStart =
MIRBuilder.buildInstr(Mips::ADJCALLSTACKDOWN);
const bool IsCalleeGlobalPIC =
Info.Callee.isGlobal() && TM.isPositionIndependent();
MachineInstrBuilder MIB = MIRBuilder.buildInstrNoInsert(
Info.Callee.isReg() || IsCalleeGlobalPIC ? Mips::JALRPseudo : Mips::JAL);
MIB.addDef(Mips::SP, RegState::Implicit);
if (IsCalleeGlobalPIC) {
Register CalleeReg =
MF.getRegInfo().createGenericVirtualRegister(LLT::pointer(0, 32));
MachineInstr *CalleeGlobalValue =
MIRBuilder.buildGlobalValue(CalleeReg, Info.Callee.getGlobal());
if (!Info.Callee.getGlobal()->hasLocalLinkage())
CalleeGlobalValue->getOperand(1).setTargetFlags(MipsII::MO_GOT_CALL);
MIB.addUse(CalleeReg);
} else
MIB.add(Info.Callee);
const TargetRegisterInfo *TRI = MF.getSubtarget().getRegisterInfo();
MIB.addRegMask(TRI->getCallPreservedMask(MF, F.getCallingConv()));
TargetLowering::ArgListTy FuncOrigArgs;
FuncOrigArgs.reserve(Info.OrigArgs.size());
SmallVector<ArgInfo, 8> ArgInfos;
SmallVector<unsigned, 8> OrigArgIndices;
unsigned i = 0;
for (auto &Arg : Info.OrigArgs) {
TargetLowering::ArgListEntry Entry;
Entry.Ty = Arg.Ty;
FuncOrigArgs.push_back(Entry);
ArgInfos.push_back(Arg);
OrigArgIndices.push_back(i);
++i;
}
SmallVector<ISD::OutputArg, 8> Outs;
subTargetRegTypeForCallingConv(F, ArgInfos, OrigArgIndices, Outs);
SmallVector<CCValAssign, 8> ArgLocs;
bool IsCalleeVarArg = false;
if (Info.Callee.isGlobal()) {
const Function *CF = static_cast<const Function *>(Info.Callee.getGlobal());
IsCalleeVarArg = CF->isVarArg();
}
MipsCCState CCInfo(F.getCallingConv(), IsCalleeVarArg, MF, ArgLocs,
F.getContext());
CCInfo.AllocateStack(ABI.GetCalleeAllocdArgSizeInBytes(Info.CallConv),
Align(1));
const char *Call =
Info.Callee.isSymbol() ? Info.Callee.getSymbolName() : nullptr;
CCInfo.AnalyzeCallOperands(Outs, TLI.CCAssignFnForCall(), FuncOrigArgs, Call);
setLocInfo(ArgLocs, Outs);
MipsOutgoingValueHandler RetHandler(MIRBuilder, MF.getRegInfo(), MIB);
if (!RetHandler.handle(ArgLocs, ArgInfos)) {
return false;
}
unsigned NextStackOffset = CCInfo.getNextStackOffset();
const TargetFrameLowering *TFL = MF.getSubtarget().getFrameLowering();
unsigned StackAlignment = TFL->getStackAlignment();
NextStackOffset = alignTo(NextStackOffset, StackAlignment);
CallSeqStart.addImm(NextStackOffset).addImm(0);
if (IsCalleeGlobalPIC) {
MIRBuilder.buildCopy(
Register(Mips::GP),
MF.getInfo<MipsFunctionInfo>()->getGlobalBaseRegForGlobalISel(MF));
MIB.addDef(Mips::GP, RegState::Implicit);
}
MIRBuilder.insertInstr(MIB);
if (MIB->getOpcode() == Mips::JALRPseudo) {
const MipsSubtarget &STI =
static_cast<const MipsSubtarget &>(MIRBuilder.getMF().getSubtarget());
MIB.constrainAllUses(MIRBuilder.getTII(), *STI.getRegisterInfo(),
*STI.getRegBankInfo());
}
if (!Info.OrigRet.Ty->isVoidTy()) {
ArgInfos.clear();
SmallVector<unsigned, 8> OrigRetIndices;
splitToValueTypes(DL, Info.OrigRet, 0, ArgInfos, OrigRetIndices);
SmallVector<ISD::InputArg, 8> Ins;
subTargetRegTypeForCallingConv(F, ArgInfos, OrigRetIndices, Ins);
SmallVector<CCValAssign, 8> ArgLocs;
MipsCCState CCInfo(F.getCallingConv(), F.isVarArg(), MF, ArgLocs,
F.getContext());
CCInfo.AnalyzeCallResult(Ins, TLI.CCAssignFnForReturn(), Info.OrigRet.Ty,
Call);
setLocInfo(ArgLocs, Ins);
CallReturnHandler Handler(MIRBuilder, MF.getRegInfo(), MIB);
if (!Handler.handle(ArgLocs, ArgInfos))
return false;
}
MIRBuilder.buildInstr(Mips::ADJCALLSTACKUP).addImm(NextStackOffset).addImm(0);
return true;
}
template <typename T>
void MipsCallLowering::subTargetRegTypeForCallingConv(
const Function &F, ArrayRef<ArgInfo> Args,
ArrayRef<unsigned> OrigArgIndices, SmallVectorImpl<T> &ISDArgs) const {
const DataLayout &DL = F.getParent()->getDataLayout();
const MipsTargetLowering &TLI = *getTLI<MipsTargetLowering>();
unsigned ArgNo = 0;
for (auto &Arg : Args) {
EVT VT = TLI.getValueType(DL, Arg.Ty);
MVT RegisterVT = TLI.getRegisterTypeForCallingConv(F.getContext(),
F.getCallingConv(), VT);
unsigned NumRegs = TLI.getNumRegistersForCallingConv(
F.getContext(), F.getCallingConv(), VT);
for (unsigned i = 0; i < NumRegs; ++i) {
ISD::ArgFlagsTy Flags = Arg.Flags[0];
if (i == 0)
Flags.setOrigAlign(TLI.getABIAlignmentForCallingConv(Arg.Ty, DL));
else
Flags.setOrigAlign(Align(1));
ISDArgs.emplace_back(Flags, RegisterVT, VT, true, OrigArgIndices[ArgNo],
0);
}
++ArgNo;
}
}
void MipsCallLowering::splitToValueTypes(
const DataLayout &DL, const ArgInfo &OrigArg, unsigned OriginalIndex,
SmallVectorImpl<ArgInfo> &SplitArgs,
SmallVectorImpl<unsigned> &SplitArgsOrigIndices) const {
SmallVector<EVT, 4> SplitEVTs;
SmallVector<Register, 4> SplitVRegs;
const MipsTargetLowering &TLI = *getTLI<MipsTargetLowering>();
LLVMContext &Ctx = OrigArg.Ty->getContext();
ComputeValueVTs(TLI, DL, OrigArg.Ty, SplitEVTs);
for (unsigned i = 0; i < SplitEVTs.size(); ++i) {
ArgInfo Info = ArgInfo{OrigArg.Regs[i], SplitEVTs[i].getTypeForEVT(Ctx)};
Info.Flags = OrigArg.Flags;
SplitArgs.push_back(Info);
SplitArgsOrigIndices.push_back(OriginalIndex);
}
}