blob: a705ebb6b193bc9e6d27fd4a2b87fb2c6b62fd2c [file] [log] [blame]
//===- MipsCallLowering.cpp -------------------------------------*- C++ -*-===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
/// \file
/// This file implements the lowering of LLVM calls to machine code calls for
/// GlobalISel.
//
//===----------------------------------------------------------------------===//
#include "MipsCallLowering.h"
#include "MipsCCState.h"
#include "MipsTargetMachine.h"
#include "llvm/CodeGen/GlobalISel/MachineIRBuilder.h"
using namespace llvm;
MipsCallLowering::MipsCallLowering(const MipsTargetLowering &TLI)
: CallLowering(&TLI) {}
bool MipsCallLowering::MipsHandler::assign(const CCValAssign &VA,
unsigned vreg) {
if (VA.isRegLoc()) {
assignValueToReg(vreg, VA.getLocReg());
} else if (VA.isMemLoc()) {
unsigned Size = alignTo(VA.getValVT().getSizeInBits(), 8) / 8;
unsigned Offset = VA.getLocMemOffset();
MachinePointerInfo MPO;
unsigned StackAddr = getStackAddress(Size, Offset, MPO);
assignValueToAddress(vreg, StackAddr, Size, MPO);
} else {
return false;
}
return true;
}
namespace {
class IncomingValueHandler : public MipsCallLowering::MipsHandler {
public:
IncomingValueHandler(MachineIRBuilder &MIRBuilder, MachineRegisterInfo &MRI)
: MipsHandler(MIRBuilder, MRI) {}
bool handle(ArrayRef<CCValAssign> ArgLocs,
ArrayRef<CallLowering::ArgInfo> Args);
private:
void assignValueToReg(unsigned ValVReg, unsigned PhysReg) override;
unsigned getStackAddress(uint64_t Size, int64_t Offset,
MachinePointerInfo &MPO) override;
void assignValueToAddress(unsigned ValVReg, unsigned Addr, uint64_t Size,
MachinePointerInfo &MPO) override;
virtual void markPhysRegUsed(unsigned PhysReg) {
MIRBuilder.getMBB().addLiveIn(PhysReg);
}
void buildLoad(unsigned Val, unsigned Addr, uint64_t Size, unsigned Alignment,
MachinePointerInfo &MPO) {
MachineMemOperand *MMO = MIRBuilder.getMF().getMachineMemOperand(
MPO, MachineMemOperand::MOLoad, Size, Alignment);
MIRBuilder.buildLoad(Val, Addr, *MMO);
}
};
class CallReturnHandler : public IncomingValueHandler {
public:
CallReturnHandler(MachineIRBuilder &MIRBuilder, MachineRegisterInfo &MRI,
MachineInstrBuilder &MIB)
: IncomingValueHandler(MIRBuilder, MRI), MIB(MIB) {}
private:
void markPhysRegUsed(unsigned PhysReg) override {
MIB.addDef(PhysReg, RegState::Implicit);
}
MachineInstrBuilder &MIB;
};
} // end anonymous namespace
void IncomingValueHandler::assignValueToReg(unsigned ValVReg,
unsigned PhysReg) {
MIRBuilder.buildCopy(ValVReg, PhysReg);
markPhysRegUsed(PhysReg);
}
unsigned IncomingValueHandler::getStackAddress(uint64_t Size, int64_t Offset,
MachinePointerInfo &MPO) {
MachineFrameInfo &MFI = MIRBuilder.getMF().getFrameInfo();
int FI = MFI.CreateFixedObject(Size, Offset, true);
MPO = MachinePointerInfo::getFixedStack(MIRBuilder.getMF(), FI);
unsigned AddrReg = MRI.createGenericVirtualRegister(LLT::pointer(0, 32));
MIRBuilder.buildFrameIndex(AddrReg, FI);
return AddrReg;
}
void IncomingValueHandler::assignValueToAddress(unsigned ValVReg, unsigned Addr,
uint64_t Size,
MachinePointerInfo &MPO) {
// If the value is not extended, a simple load will suffice.
buildLoad(ValVReg, Addr, Size, /* Alignment */ 0, MPO);
}
bool IncomingValueHandler::handle(ArrayRef<CCValAssign> ArgLocs,
ArrayRef<CallLowering::ArgInfo> Args) {
for (unsigned i = 0, ArgsSize = Args.size(); i < ArgsSize; ++i) {
if (!assign(ArgLocs[i], Args[i].Reg))
return false;
}
return true;
}
namespace {
class OutgoingValueHandler : public MipsCallLowering::MipsHandler {
public:
OutgoingValueHandler(MachineIRBuilder &MIRBuilder, MachineRegisterInfo &MRI,
MachineInstrBuilder &MIB)
: MipsHandler(MIRBuilder, MRI), MIB(MIB) {}
bool handle(ArrayRef<CCValAssign> ArgLocs,
ArrayRef<CallLowering::ArgInfo> Args);
private:
void assignValueToReg(unsigned ValVReg, unsigned PhysReg) override;
unsigned getStackAddress(uint64_t Size, int64_t Offset,
MachinePointerInfo &MPO) override;
void assignValueToAddress(unsigned ValVReg, unsigned Addr, uint64_t Size,
MachinePointerInfo &MPO) override;
MachineInstrBuilder &MIB;
};
} // end anonymous namespace
void OutgoingValueHandler::assignValueToReg(unsigned ValVReg,
unsigned PhysReg) {
MIRBuilder.buildCopy(PhysReg, ValVReg);
MIB.addUse(PhysReg, RegState::Implicit);
}
unsigned OutgoingValueHandler::getStackAddress(uint64_t Size, int64_t Offset,
MachinePointerInfo &MPO) {
LLT p0 = LLT::pointer(0, 32);
LLT s32 = LLT::scalar(32);
unsigned SPReg = MRI.createGenericVirtualRegister(p0);
MIRBuilder.buildCopy(SPReg, Mips::SP);
unsigned OffsetReg = MRI.createGenericVirtualRegister(s32);
MIRBuilder.buildConstant(OffsetReg, Offset);
unsigned AddrReg = MRI.createGenericVirtualRegister(p0);
MIRBuilder.buildGEP(AddrReg, SPReg, OffsetReg);
MPO = MachinePointerInfo::getStack(MIRBuilder.getMF(), Offset);
return AddrReg;
}
void OutgoingValueHandler::assignValueToAddress(unsigned ValVReg, unsigned Addr,
uint64_t Size,
MachinePointerInfo &MPO) {
MachineMemOperand *MMO = MIRBuilder.getMF().getMachineMemOperand(
MPO, MachineMemOperand::MOStore, Size, /* Alignment */ 0);
MIRBuilder.buildStore(ValVReg, Addr, *MMO);
}
bool OutgoingValueHandler::handle(ArrayRef<CCValAssign> ArgLocs,
ArrayRef<CallLowering::ArgInfo> Args) {
for (unsigned i = 0; i < Args.size(); ++i) {
if (!assign(ArgLocs[i], Args[i].Reg))
return false;
}
return true;
}
static bool isSupportedType(Type *T) {
if (T->isIntegerTy() && T->getScalarSizeInBits() == 32)
return true;
if (T->isPointerTy())
return true;
return false;
}
bool MipsCallLowering::lowerReturn(MachineIRBuilder &MIRBuilder,
const Value *Val, unsigned VReg) const {
MachineInstrBuilder Ret = MIRBuilder.buildInstrNoInsert(Mips::RetRA);
if (Val != nullptr) {
if (!isSupportedType(Val->getType()))
return false;
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(VReg, Val->getType());
setArgFlags(ArgRetInfo, AttributeList::ReturnIndex, DL, F);
splitToValueTypes(ArgRetInfo, 0, RetInfos, OrigArgIndices);
SmallVector<ISD::OutputArg, 8> Outs;
subTargetRegTypeForCallingConv(
MIRBuilder, RetInfos, OrigArgIndices,
[&](ISD::ArgFlagsTy flags, EVT vt, EVT argvt, bool used,
unsigned origIdx, unsigned partOffs) {
Outs.emplace_back(flags, vt, argvt, used, origIdx, partOffs);
});
SmallVector<CCValAssign, 16> ArgLocs;
MipsCCState CCInfo(F.getCallingConv(), F.isVarArg(), MF, ArgLocs,
F.getContext());
CCInfo.AnalyzeReturn(Outs, TLI.CCAssignFnForReturn());
OutgoingValueHandler 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<unsigned> VRegs) const {
// Quick exit if there aren't any args.
if (F.arg_empty())
return true;
if (F.isVarArg()) {
return false;
}
for (auto &Arg : F.args()) {
if (!isSupportedType(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);
splitToValueTypes(AInfo, i, ArgInfos, OrigArgIndices);
++i;
}
SmallVector<ISD::InputArg, 8> Ins;
subTargetRegTypeForCallingConv(
MIRBuilder, ArgInfos, OrigArgIndices,
[&](ISD::ArgFlagsTy flags, EVT vt, EVT argvt, bool used, unsigned origIdx,
unsigned partOffs) {
Ins.emplace_back(flags, vt, argvt, used, origIdx, partOffs);
});
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()),
1);
CCInfo.AnalyzeFormalArguments(Ins, TLI.CCAssignFnForCall());
IncomingValueHandler Handler(MIRBuilder, MF.getRegInfo());
if (!Handler.handle(ArgLocs, ArgInfos))
return false;
return true;
}
bool MipsCallLowering::lowerCall(MachineIRBuilder &MIRBuilder,
CallingConv::ID CallConv,
const MachineOperand &Callee,
const ArgInfo &OrigRet,
ArrayRef<ArgInfo> OrigArgs) const {
if (CallConv != CallingConv::C)
return false;
for (auto &Arg : OrigArgs) {
if (!isSupportedType(Arg.Ty))
return false;
if (Arg.Flags.isByVal() || Arg.Flags.isSRet())
return false;
}
if (OrigRet.Reg && !isSupportedType(OrigRet.Ty))
return false;
MachineFunction &MF = MIRBuilder.getMF();
const Function &F = MF.getFunction();
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);
// FIXME: Add support for pic calling sequences, long call sequences for O32,
// N32 and N64. First handle the case when Callee.isReg().
if (Callee.isReg())
return false;
MachineInstrBuilder MIB = MIRBuilder.buildInstrNoInsert(Mips::JAL);
MIB.addDef(Mips::SP, RegState::Implicit);
MIB.add(Callee);
const TargetRegisterInfo *TRI = MF.getSubtarget().getRegisterInfo();
MIB.addRegMask(TRI->getCallPreservedMask(MF, F.getCallingConv()));
TargetLowering::ArgListTy FuncOrigArgs;
FuncOrigArgs.reserve(OrigArgs.size());
SmallVector<ArgInfo, 8> ArgInfos;
SmallVector<unsigned, 8> OrigArgIndices;
unsigned i = 0;
for (auto &Arg : OrigArgs) {
TargetLowering::ArgListEntry Entry;
Entry.Ty = Arg.Ty;
FuncOrigArgs.push_back(Entry);
splitToValueTypes(Arg, i, ArgInfos, OrigArgIndices);
++i;
}
SmallVector<ISD::OutputArg, 8> Outs;
subTargetRegTypeForCallingConv(
MIRBuilder, ArgInfos, OrigArgIndices,
[&](ISD::ArgFlagsTy flags, EVT vt, EVT argvt, bool used, unsigned origIdx,
unsigned partOffs) {
Outs.emplace_back(flags, vt, argvt, used, origIdx, partOffs);
});
SmallVector<CCValAssign, 8> ArgLocs;
MipsCCState CCInfo(F.getCallingConv(), F.isVarArg(), MF, ArgLocs,
F.getContext());
CCInfo.AllocateStack(ABI.GetCalleeAllocdArgSizeInBytes(CallConv), 1);
const char *Call = Callee.isSymbol() ? Callee.getSymbolName() : nullptr;
CCInfo.AnalyzeCallOperands(Outs, TLI.CCAssignFnForCall(), FuncOrigArgs, Call);
OutgoingValueHandler 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);
MIRBuilder.insertInstr(MIB);
if (OrigRet.Reg) {
ArgInfos.clear();
SmallVector<unsigned, 8> OrigRetIndices;
splitToValueTypes(OrigRet, 0, ArgInfos, OrigRetIndices);
SmallVector<ISD::InputArg, 8> Ins;
subTargetRegTypeForCallingConv(
MIRBuilder, ArgInfos, OrigRetIndices,
[&](ISD::ArgFlagsTy flags, EVT vt, EVT argvt, bool used,
unsigned origIdx, unsigned partOffs) {
Ins.emplace_back(flags, vt, argvt, used, origIdx, partOffs);
});
SmallVector<CCValAssign, 8> ArgLocs;
MipsCCState CCInfo(F.getCallingConv(), F.isVarArg(), MF, ArgLocs,
F.getContext());
CCInfo.AnalyzeCallResult(Ins, TLI.CCAssignFnForReturn(), OrigRet.Ty, Call);
CallReturnHandler Handler(MIRBuilder, MF.getRegInfo(), MIB);
if (!Handler.handle(ArgLocs, ArgInfos))
return false;
}
MIRBuilder.buildInstr(Mips::ADJCALLSTACKUP).addImm(NextStackOffset).addImm(0);
return true;
}
void MipsCallLowering::subTargetRegTypeForCallingConv(
MachineIRBuilder &MIRBuilder, ArrayRef<ArgInfo> Args,
ArrayRef<unsigned> OrigArgIndices, const FunTy &PushBack) const {
MachineFunction &MF = MIRBuilder.getMF();
const Function &F = MF.getFunction();
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);
ISD::ArgFlagsTy Flags = Arg.Flags;
Flags.setOrigAlign(TLI.getABIAlignmentForCallingConv(Arg.Ty, DL));
PushBack(Flags, RegisterVT, VT, true, OrigArgIndices[ArgNo], 0);
++ArgNo;
}
}
void MipsCallLowering::splitToValueTypes(
const ArgInfo &OrigArg, unsigned OriginalIndex,
SmallVectorImpl<ArgInfo> &SplitArgs,
SmallVectorImpl<unsigned> &SplitArgsOrigIndices) const {
// TODO : perform structure and array split. For now we only deal with
// types that pass isSupportedType check.
SplitArgs.push_back(OrigArg);
SplitArgsOrigIndices.push_back(OriginalIndex);
}