llvm-project/llvm/lib/Target/Mips/MipsSEInstrInfo.cpp

607 lines
23 KiB
C++

//===-- MipsSEInstrInfo.cpp - Mips32/64 Instruction Information -----------===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This file contains the Mips32/64 implementation of the TargetInstrInfo class.
//
//===----------------------------------------------------------------------===//
#include "MipsSEInstrInfo.h"
#include "InstPrinter/MipsInstPrinter.h"
#include "MipsMachineFunction.h"
#include "MipsTargetMachine.h"
#include "llvm/ADT/STLExtras.h"
#include "llvm/CodeGen/MachineInstrBuilder.h"
#include "llvm/CodeGen/MachineRegisterInfo.h"
#include "llvm/Support/CommandLine.h"
#include "llvm/Support/ErrorHandling.h"
#include "llvm/Support/TargetRegistry.h"
using namespace llvm;
MipsSEInstrInfo::MipsSEInstrInfo(MipsTargetMachine &tm)
: MipsInstrInfo(tm,
tm.getRelocationModel() == Reloc::PIC_ ? Mips::B : Mips::J),
RI(*tm.getSubtargetImpl()),
IsN64(tm.getSubtarget<MipsSubtarget>().isABI_N64()) {}
const MipsRegisterInfo &MipsSEInstrInfo::getRegisterInfo() const {
return RI;
}
/// isLoadFromStackSlot - If the specified machine instruction is a direct
/// load from a stack slot, return the virtual or physical register number of
/// the destination along with the FrameIndex of the loaded stack slot. If
/// not, return 0. This predicate must return 0 if the instruction has
/// any side effects other than loading from the stack slot.
unsigned MipsSEInstrInfo::
isLoadFromStackSlot(const MachineInstr *MI, int &FrameIndex) const
{
unsigned Opc = MI->getOpcode();
if ((Opc == Mips::LW) || (Opc == Mips::LD) ||
(Opc == Mips::LWC1) || (Opc == Mips::LDC1) || (Opc == Mips::LDC164)) {
if ((MI->getOperand(1).isFI()) && // is a stack slot
(MI->getOperand(2).isImm()) && // the imm is zero
(isZeroImm(MI->getOperand(2)))) {
FrameIndex = MI->getOperand(1).getIndex();
return MI->getOperand(0).getReg();
}
}
return 0;
}
/// isStoreToStackSlot - If the specified machine instruction is a direct
/// store to a stack slot, return the virtual or physical register number of
/// the source reg along with the FrameIndex of the loaded stack slot. If
/// not, return 0. This predicate must return 0 if the instruction has
/// any side effects other than storing to the stack slot.
unsigned MipsSEInstrInfo::
isStoreToStackSlot(const MachineInstr *MI, int &FrameIndex) const
{
unsigned Opc = MI->getOpcode();
if ((Opc == Mips::SW) || (Opc == Mips::SD) ||
(Opc == Mips::SWC1) || (Opc == Mips::SDC1) || (Opc == Mips::SDC164)) {
if ((MI->getOperand(1).isFI()) && // is a stack slot
(MI->getOperand(2).isImm()) && // the imm is zero
(isZeroImm(MI->getOperand(2)))) {
FrameIndex = MI->getOperand(1).getIndex();
return MI->getOperand(0).getReg();
}
}
return 0;
}
void MipsSEInstrInfo::copyPhysReg(MachineBasicBlock &MBB,
MachineBasicBlock::iterator I, DebugLoc DL,
unsigned DestReg, unsigned SrcReg,
bool KillSrc) const {
unsigned Opc = 0, ZeroReg = 0;
bool isMicroMips = TM.getSubtarget<MipsSubtarget>().inMicroMipsMode();
if (Mips::GPR32RegClass.contains(DestReg)) { // Copy to CPU Reg.
if (Mips::GPR32RegClass.contains(SrcReg)) {
if (isMicroMips)
Opc = Mips::MOVE16_MM;
else
Opc = Mips::ADDu, ZeroReg = Mips::ZERO;
} else if (Mips::CCRRegClass.contains(SrcReg))
Opc = Mips::CFC1;
else if (Mips::FGR32RegClass.contains(SrcReg))
Opc = Mips::MFC1;
else if (Mips::HI32RegClass.contains(SrcReg)) {
Opc = isMicroMips ? Mips::MFHI16_MM : Mips::MFHI;
SrcReg = 0;
} else if (Mips::LO32RegClass.contains(SrcReg)) {
Opc = isMicroMips ? Mips::MFLO16_MM : Mips::MFLO;
SrcReg = 0;
} else if (Mips::HI32DSPRegClass.contains(SrcReg))
Opc = Mips::MFHI_DSP;
else if (Mips::LO32DSPRegClass.contains(SrcReg))
Opc = Mips::MFLO_DSP;
else if (Mips::DSPCCRegClass.contains(SrcReg)) {
BuildMI(MBB, I, DL, get(Mips::RDDSP), DestReg).addImm(1 << 4)
.addReg(SrcReg, RegState::Implicit | getKillRegState(KillSrc));
return;
}
else if (Mips::MSACtrlRegClass.contains(SrcReg))
Opc = Mips::CFCMSA;
}
else if (Mips::GPR32RegClass.contains(SrcReg)) { // Copy from CPU Reg.
if (Mips::CCRRegClass.contains(DestReg))
Opc = Mips::CTC1;
else if (Mips::FGR32RegClass.contains(DestReg))
Opc = Mips::MTC1;
else if (Mips::HI32RegClass.contains(DestReg))
Opc = Mips::MTHI, DestReg = 0;
else if (Mips::LO32RegClass.contains(DestReg))
Opc = Mips::MTLO, DestReg = 0;
else if (Mips::HI32DSPRegClass.contains(DestReg))
Opc = Mips::MTHI_DSP;
else if (Mips::LO32DSPRegClass.contains(DestReg))
Opc = Mips::MTLO_DSP;
else if (Mips::DSPCCRegClass.contains(DestReg)) {
BuildMI(MBB, I, DL, get(Mips::WRDSP))
.addReg(SrcReg, getKillRegState(KillSrc)).addImm(1 << 4)
.addReg(DestReg, RegState::ImplicitDefine);
return;
}
else if (Mips::MSACtrlRegClass.contains(DestReg))
Opc = Mips::CTCMSA;
}
else if (Mips::FGR32RegClass.contains(DestReg, SrcReg))
Opc = Mips::FMOV_S;
else if (Mips::AFGR64RegClass.contains(DestReg, SrcReg))
Opc = Mips::FMOV_D32;
else if (Mips::FGR64RegClass.contains(DestReg, SrcReg))
Opc = Mips::FMOV_D64;
else if (Mips::GPR64RegClass.contains(DestReg)) { // Copy to CPU64 Reg.
if (Mips::GPR64RegClass.contains(SrcReg))
Opc = Mips::DADDu, ZeroReg = Mips::ZERO_64;
else if (Mips::HI64RegClass.contains(SrcReg))
Opc = Mips::MFHI64, SrcReg = 0;
else if (Mips::LO64RegClass.contains(SrcReg))
Opc = Mips::MFLO64, SrcReg = 0;
else if (Mips::FGR64RegClass.contains(SrcReg))
Opc = Mips::DMFC1;
}
else if (Mips::GPR64RegClass.contains(SrcReg)) { // Copy from CPU64 Reg.
if (Mips::HI64RegClass.contains(DestReg))
Opc = Mips::MTHI64, DestReg = 0;
else if (Mips::LO64RegClass.contains(DestReg))
Opc = Mips::MTLO64, DestReg = 0;
else if (Mips::FGR64RegClass.contains(DestReg))
Opc = Mips::DMTC1;
}
else if (Mips::MSA128BRegClass.contains(DestReg)) { // Copy to MSA reg
if (Mips::MSA128BRegClass.contains(SrcReg))
Opc = Mips::MOVE_V;
}
assert(Opc && "Cannot copy registers");
MachineInstrBuilder MIB = BuildMI(MBB, I, DL, get(Opc));
if (DestReg)
MIB.addReg(DestReg, RegState::Define);
if (SrcReg)
MIB.addReg(SrcReg, getKillRegState(KillSrc));
if (ZeroReg)
MIB.addReg(ZeroReg);
}
void MipsSEInstrInfo::
storeRegToStack(MachineBasicBlock &MBB, MachineBasicBlock::iterator I,
unsigned SrcReg, bool isKill, int FI,
const TargetRegisterClass *RC, const TargetRegisterInfo *TRI,
int64_t Offset) const {
DebugLoc DL;
if (I != MBB.end()) DL = I->getDebugLoc();
MachineMemOperand *MMO = GetMemOperand(MBB, FI, MachineMemOperand::MOStore);
unsigned Opc = 0;
if (Mips::GPR32RegClass.hasSubClassEq(RC))
Opc = Mips::SW;
else if (Mips::GPR64RegClass.hasSubClassEq(RC))
Opc = Mips::SD;
else if (Mips::ACC64RegClass.hasSubClassEq(RC))
Opc = Mips::STORE_ACC64;
else if (Mips::ACC64DSPRegClass.hasSubClassEq(RC))
Opc = Mips::STORE_ACC64DSP;
else if (Mips::ACC128RegClass.hasSubClassEq(RC))
Opc = Mips::STORE_ACC128;
else if (Mips::DSPCCRegClass.hasSubClassEq(RC))
Opc = Mips::STORE_CCOND_DSP;
else if (Mips::FGR32RegClass.hasSubClassEq(RC))
Opc = Mips::SWC1;
else if (Mips::AFGR64RegClass.hasSubClassEq(RC))
Opc = Mips::SDC1;
else if (Mips::FGR64RegClass.hasSubClassEq(RC))
Opc = Mips::SDC164;
else if (RC->hasType(MVT::v16i8))
Opc = Mips::ST_B;
else if (RC->hasType(MVT::v8i16) || RC->hasType(MVT::v8f16))
Opc = Mips::ST_H;
else if (RC->hasType(MVT::v4i32) || RC->hasType(MVT::v4f32))
Opc = Mips::ST_W;
else if (RC->hasType(MVT::v2i64) || RC->hasType(MVT::v2f64))
Opc = Mips::ST_D;
assert(Opc && "Register class not handled!");
BuildMI(MBB, I, DL, get(Opc)).addReg(SrcReg, getKillRegState(isKill))
.addFrameIndex(FI).addImm(Offset).addMemOperand(MMO);
}
void MipsSEInstrInfo::
loadRegFromStack(MachineBasicBlock &MBB, MachineBasicBlock::iterator I,
unsigned DestReg, int FI, const TargetRegisterClass *RC,
const TargetRegisterInfo *TRI, int64_t Offset) const {
DebugLoc DL;
if (I != MBB.end()) DL = I->getDebugLoc();
MachineMemOperand *MMO = GetMemOperand(MBB, FI, MachineMemOperand::MOLoad);
unsigned Opc = 0;
if (Mips::GPR32RegClass.hasSubClassEq(RC))
Opc = Mips::LW;
else if (Mips::GPR64RegClass.hasSubClassEq(RC))
Opc = Mips::LD;
else if (Mips::ACC64RegClass.hasSubClassEq(RC))
Opc = Mips::LOAD_ACC64;
else if (Mips::ACC64DSPRegClass.hasSubClassEq(RC))
Opc = Mips::LOAD_ACC64DSP;
else if (Mips::ACC128RegClass.hasSubClassEq(RC))
Opc = Mips::LOAD_ACC128;
else if (Mips::DSPCCRegClass.hasSubClassEq(RC))
Opc = Mips::LOAD_CCOND_DSP;
else if (Mips::FGR32RegClass.hasSubClassEq(RC))
Opc = Mips::LWC1;
else if (Mips::AFGR64RegClass.hasSubClassEq(RC))
Opc = Mips::LDC1;
else if (Mips::FGR64RegClass.hasSubClassEq(RC))
Opc = Mips::LDC164;
else if (RC->hasType(MVT::v16i8))
Opc = Mips::LD_B;
else if (RC->hasType(MVT::v8i16) || RC->hasType(MVT::v8f16))
Opc = Mips::LD_H;
else if (RC->hasType(MVT::v4i32) || RC->hasType(MVT::v4f32))
Opc = Mips::LD_W;
else if (RC->hasType(MVT::v2i64) || RC->hasType(MVT::v2f64))
Opc = Mips::LD_D;
assert(Opc && "Register class not handled!");
BuildMI(MBB, I, DL, get(Opc), DestReg).addFrameIndex(FI).addImm(Offset)
.addMemOperand(MMO);
}
bool MipsSEInstrInfo::expandPostRAPseudo(MachineBasicBlock::iterator MI) const {
MachineBasicBlock &MBB = *MI->getParent();
bool isMicroMips = TM.getSubtarget<MipsSubtarget>().inMicroMipsMode();
unsigned Opc;
switch(MI->getDesc().getOpcode()) {
default:
return false;
case Mips::RetRA:
expandRetRA(MBB, MI, Mips::RET);
break;
case Mips::PseudoMFHI:
Opc = isMicroMips ? Mips::MFHI16_MM : Mips::MFHI;
expandPseudoMFHiLo(MBB, MI, Opc);
break;
case Mips::PseudoMFLO:
Opc = isMicroMips ? Mips::MFLO16_MM : Mips::MFLO;
expandPseudoMFHiLo(MBB, MI, Opc);
break;
case Mips::PseudoMFHI64:
expandPseudoMFHiLo(MBB, MI, Mips::MFHI64);
break;
case Mips::PseudoMFLO64:
expandPseudoMFHiLo(MBB, MI, Mips::MFLO64);
break;
case Mips::PseudoMTLOHI:
expandPseudoMTLoHi(MBB, MI, Mips::MTLO, Mips::MTHI, false);
break;
case Mips::PseudoMTLOHI64:
expandPseudoMTLoHi(MBB, MI, Mips::MTLO64, Mips::MTHI64, false);
break;
case Mips::PseudoMTLOHI_DSP:
expandPseudoMTLoHi(MBB, MI, Mips::MTLO_DSP, Mips::MTHI_DSP, true);
break;
case Mips::PseudoCVT_S_W:
expandCvtFPInt(MBB, MI, Mips::CVT_S_W, Mips::MTC1, false);
break;
case Mips::PseudoCVT_D32_W:
expandCvtFPInt(MBB, MI, Mips::CVT_D32_W, Mips::MTC1, false);
break;
case Mips::PseudoCVT_S_L:
expandCvtFPInt(MBB, MI, Mips::CVT_S_L, Mips::DMTC1, true);
break;
case Mips::PseudoCVT_D64_W:
expandCvtFPInt(MBB, MI, Mips::CVT_D64_W, Mips::MTC1, true);
break;
case Mips::PseudoCVT_D64_L:
expandCvtFPInt(MBB, MI, Mips::CVT_D64_L, Mips::DMTC1, true);
break;
case Mips::BuildPairF64:
expandBuildPairF64(MBB, MI, false);
break;
case Mips::BuildPairF64_64:
expandBuildPairF64(MBB, MI, true);
break;
case Mips::ExtractElementF64:
expandExtractElementF64(MBB, MI, false);
break;
case Mips::ExtractElementF64_64:
expandExtractElementF64(MBB, MI, true);
break;
case Mips::MIPSeh_return32:
case Mips::MIPSeh_return64:
expandEhReturn(MBB, MI);
break;
}
MBB.erase(MI);
return true;
}
/// getOppositeBranchOpc - Return the inverse of the specified
/// opcode, e.g. turning BEQ to BNE.
unsigned MipsSEInstrInfo::getOppositeBranchOpc(unsigned Opc) const {
switch (Opc) {
default: llvm_unreachable("Illegal opcode!");
case Mips::BEQ: return Mips::BNE;
case Mips::BNE: return Mips::BEQ;
case Mips::BGTZ: return Mips::BLEZ;
case Mips::BGEZ: return Mips::BLTZ;
case Mips::BLTZ: return Mips::BGEZ;
case Mips::BLEZ: return Mips::BGTZ;
case Mips::BEQ64: return Mips::BNE64;
case Mips::BNE64: return Mips::BEQ64;
case Mips::BGTZ64: return Mips::BLEZ64;
case Mips::BGEZ64: return Mips::BLTZ64;
case Mips::BLTZ64: return Mips::BGEZ64;
case Mips::BLEZ64: return Mips::BGTZ64;
case Mips::BC1T: return Mips::BC1F;
case Mips::BC1F: return Mips::BC1T;
}
}
/// Adjust SP by Amount bytes.
void MipsSEInstrInfo::adjustStackPtr(unsigned SP, int64_t Amount,
MachineBasicBlock &MBB,
MachineBasicBlock::iterator I) const {
const MipsSubtarget &STI = TM.getSubtarget<MipsSubtarget>();
DebugLoc DL = I != MBB.end() ? I->getDebugLoc() : DebugLoc();
unsigned ADDu = STI.isABI_N64() ? Mips::DADDu : Mips::ADDu;
unsigned ADDiu = STI.isABI_N64() ? Mips::DADDiu : Mips::ADDiu;
if (isInt<16>(Amount))// addi sp, sp, amount
BuildMI(MBB, I, DL, get(ADDiu), SP).addReg(SP).addImm(Amount);
else { // Expand immediate that doesn't fit in 16-bit.
unsigned Reg = loadImmediate(Amount, MBB, I, DL, 0);
BuildMI(MBB, I, DL, get(ADDu), SP).addReg(SP).addReg(Reg, RegState::Kill);
}
}
/// This function generates the sequence of instructions needed to get the
/// result of adding register REG and immediate IMM.
unsigned
MipsSEInstrInfo::loadImmediate(int64_t Imm, MachineBasicBlock &MBB,
MachineBasicBlock::iterator II, DebugLoc DL,
unsigned *NewImm) const {
MipsAnalyzeImmediate AnalyzeImm;
const MipsSubtarget &STI = TM.getSubtarget<MipsSubtarget>();
MachineRegisterInfo &RegInfo = MBB.getParent()->getRegInfo();
unsigned Size = STI.isABI_N64() ? 64 : 32;
unsigned LUi = STI.isABI_N64() ? Mips::LUi64 : Mips::LUi;
unsigned ZEROReg = STI.isABI_N64() ? Mips::ZERO_64 : Mips::ZERO;
const TargetRegisterClass *RC = STI.isABI_N64() ?
&Mips::GPR64RegClass : &Mips::GPR32RegClass;
bool LastInstrIsADDiu = NewImm;
const MipsAnalyzeImmediate::InstSeq &Seq =
AnalyzeImm.Analyze(Imm, Size, LastInstrIsADDiu);
MipsAnalyzeImmediate::InstSeq::const_iterator Inst = Seq.begin();
assert(Seq.size() && (!LastInstrIsADDiu || (Seq.size() > 1)));
// The first instruction can be a LUi, which is different from other
// instructions (ADDiu, ORI and SLL) in that it does not have a register
// operand.
unsigned Reg = RegInfo.createVirtualRegister(RC);
if (Inst->Opc == LUi)
BuildMI(MBB, II, DL, get(LUi), Reg).addImm(SignExtend64<16>(Inst->ImmOpnd));
else
BuildMI(MBB, II, DL, get(Inst->Opc), Reg).addReg(ZEROReg)
.addImm(SignExtend64<16>(Inst->ImmOpnd));
// Build the remaining instructions in Seq.
for (++Inst; Inst != Seq.end() - LastInstrIsADDiu; ++Inst)
BuildMI(MBB, II, DL, get(Inst->Opc), Reg).addReg(Reg, RegState::Kill)
.addImm(SignExtend64<16>(Inst->ImmOpnd));
if (LastInstrIsADDiu)
*NewImm = Inst->ImmOpnd;
return Reg;
}
unsigned MipsSEInstrInfo::getAnalyzableBrOpc(unsigned Opc) const {
return (Opc == Mips::BEQ || Opc == Mips::BNE || Opc == Mips::BGTZ ||
Opc == Mips::BGEZ || Opc == Mips::BLTZ || Opc == Mips::BLEZ ||
Opc == Mips::BEQ64 || Opc == Mips::BNE64 || Opc == Mips::BGTZ64 ||
Opc == Mips::BGEZ64 || Opc == Mips::BLTZ64 || Opc == Mips::BLEZ64 ||
Opc == Mips::BC1T || Opc == Mips::BC1F || Opc == Mips::B ||
Opc == Mips::J) ?
Opc : 0;
}
void MipsSEInstrInfo::expandRetRA(MachineBasicBlock &MBB,
MachineBasicBlock::iterator I,
unsigned Opc) const {
BuildMI(MBB, I, I->getDebugLoc(), get(Opc)).addReg(Mips::RA);
}
std::pair<bool, bool>
MipsSEInstrInfo::compareOpndSize(unsigned Opc,
const MachineFunction &MF) const {
const MCInstrDesc &Desc = get(Opc);
assert(Desc.NumOperands == 2 && "Unary instruction expected.");
const MipsRegisterInfo *RI = &getRegisterInfo();
unsigned DstRegSize = getRegClass(Desc, 0, RI, MF)->getSize();
unsigned SrcRegSize = getRegClass(Desc, 1, RI, MF)->getSize();
return std::make_pair(DstRegSize > SrcRegSize, DstRegSize < SrcRegSize);
}
void MipsSEInstrInfo::expandPseudoMFHiLo(MachineBasicBlock &MBB,
MachineBasicBlock::iterator I,
unsigned NewOpc) const {
BuildMI(MBB, I, I->getDebugLoc(), get(NewOpc), I->getOperand(0).getReg());
}
void MipsSEInstrInfo::expandPseudoMTLoHi(MachineBasicBlock &MBB,
MachineBasicBlock::iterator I,
unsigned LoOpc,
unsigned HiOpc,
bool HasExplicitDef) const {
// Expand
// lo_hi pseudomtlohi $gpr0, $gpr1
// to these two instructions:
// mtlo $gpr0
// mthi $gpr1
DebugLoc DL = I->getDebugLoc();
const MachineOperand &SrcLo = I->getOperand(1), &SrcHi = I->getOperand(2);
MachineInstrBuilder LoInst = BuildMI(MBB, I, DL, get(LoOpc));
MachineInstrBuilder HiInst = BuildMI(MBB, I, DL, get(HiOpc));
LoInst.addReg(SrcLo.getReg(), getKillRegState(SrcLo.isKill()));
HiInst.addReg(SrcHi.getReg(), getKillRegState(SrcHi.isKill()));
// Add lo/hi registers if the mtlo/hi instructions created have explicit
// def registers.
if (HasExplicitDef) {
unsigned DstReg = I->getOperand(0).getReg();
unsigned DstLo = getRegisterInfo().getSubReg(DstReg, Mips::sub_lo);
unsigned DstHi = getRegisterInfo().getSubReg(DstReg, Mips::sub_hi);
LoInst.addReg(DstLo, RegState::Define);
HiInst.addReg(DstHi, RegState::Define);
}
}
void MipsSEInstrInfo::expandCvtFPInt(MachineBasicBlock &MBB,
MachineBasicBlock::iterator I,
unsigned CvtOpc, unsigned MovOpc,
bool IsI64) const {
const MCInstrDesc &CvtDesc = get(CvtOpc), &MovDesc = get(MovOpc);
const MachineOperand &Dst = I->getOperand(0), &Src = I->getOperand(1);
unsigned DstReg = Dst.getReg(), SrcReg = Src.getReg(), TmpReg = DstReg;
unsigned KillSrc = getKillRegState(Src.isKill());
DebugLoc DL = I->getDebugLoc();
bool DstIsLarger, SrcIsLarger;
std::tie(DstIsLarger, SrcIsLarger) =
compareOpndSize(CvtOpc, *MBB.getParent());
if (DstIsLarger)
TmpReg = getRegisterInfo().getSubReg(DstReg, Mips::sub_lo);
if (SrcIsLarger)
DstReg = getRegisterInfo().getSubReg(DstReg, Mips::sub_lo);
BuildMI(MBB, I, DL, MovDesc, TmpReg).addReg(SrcReg, KillSrc);
BuildMI(MBB, I, DL, CvtDesc, DstReg).addReg(TmpReg, RegState::Kill);
}
void MipsSEInstrInfo::expandExtractElementF64(MachineBasicBlock &MBB,
MachineBasicBlock::iterator I,
bool FP64) const {
unsigned DstReg = I->getOperand(0).getReg();
unsigned SrcReg = I->getOperand(1).getReg();
unsigned N = I->getOperand(2).getImm();
DebugLoc dl = I->getDebugLoc();
assert(N < 2 && "Invalid immediate");
unsigned SubIdx = N ? Mips::sub_hi : Mips::sub_lo;
unsigned SubReg = getRegisterInfo().getSubReg(SrcReg, SubIdx);
if (SubIdx == Mips::sub_hi && FP64) {
// FIXME: The .addReg(SrcReg, RegState::Implicit) is a white lie used to
// temporarily work around a widespread bug in the -mfp64 support.
// The problem is that none of the 32-bit fpu ops mention the fact
// that they clobber the upper 32-bits of the 64-bit FPR. Fixing that
// requires a major overhaul of the FPU implementation which can't
// be done right now due to time constraints.
// MFHC1 is one of two instructions that are affected since they are
// the only instructions that don't read the lower 32-bits.
// We therefore pretend that it reads the bottom 32-bits to
// artificially create a dependency and prevent the scheduler
// changing the behaviour of the code.
BuildMI(MBB, I, dl, get(Mips::MFHC1), DstReg).addReg(SubReg).addReg(
SrcReg, RegState::Implicit);
} else
BuildMI(MBB, I, dl, get(Mips::MFC1), DstReg).addReg(SubReg);
}
void MipsSEInstrInfo::expandBuildPairF64(MachineBasicBlock &MBB,
MachineBasicBlock::iterator I,
bool FP64) const {
unsigned DstReg = I->getOperand(0).getReg();
unsigned LoReg = I->getOperand(1).getReg(), HiReg = I->getOperand(2).getReg();
const MCInstrDesc& Mtc1Tdd = get(Mips::MTC1);
DebugLoc dl = I->getDebugLoc();
const TargetRegisterInfo &TRI = getRegisterInfo();
// For FP32 mode:
// mtc1 Lo, $fp
// mtc1 Hi, $fp + 1
// For FP64 mode:
// mtc1 Lo, $fp
// mthc1 Hi, $fp
BuildMI(MBB, I, dl, Mtc1Tdd, TRI.getSubReg(DstReg, Mips::sub_lo))
.addReg(LoReg);
if (FP64) {
// FIXME: The .addReg(DstReg, RegState::Implicit) is a white lie used to
// temporarily work around a widespread bug in the -mfp64 support.
// The problem is that none of the 32-bit fpu ops mention the fact
// that they clobber the upper 32-bits of the 64-bit FPR. Fixing that
// requires a major overhaul of the FPU implementation which can't
// be done right now due to time constraints.
// MTHC1 is one of two instructions that are affected since they are
// the only instructions that don't read the lower 32-bits.
// We therefore pretend that it reads the bottom 32-bits to
// artificially create a dependency and prevent the scheduler
// changing the behaviour of the code.
BuildMI(MBB, I, dl, get(Mips::MTHC1), TRI.getSubReg(DstReg, Mips::sub_hi))
.addReg(HiReg)
.addReg(DstReg, RegState::Implicit);
} else
BuildMI(MBB, I, dl, Mtc1Tdd, TRI.getSubReg(DstReg, Mips::sub_hi))
.addReg(HiReg);
}
void MipsSEInstrInfo::expandEhReturn(MachineBasicBlock &MBB,
MachineBasicBlock::iterator I) const {
// This pseudo instruction is generated as part of the lowering of
// ISD::EH_RETURN. We convert it to a stack increment by OffsetReg, and
// indirect jump to TargetReg
const MipsSubtarget &STI = TM.getSubtarget<MipsSubtarget>();
unsigned ADDU = STI.isABI_N64() ? Mips::DADDu : Mips::ADDu;
unsigned JR = STI.isABI_N64() ? Mips::JR64 : Mips::JR;
unsigned SP = STI.isABI_N64() ? Mips::SP_64 : Mips::SP;
unsigned RA = STI.isABI_N64() ? Mips::RA_64 : Mips::RA;
unsigned T9 = STI.isABI_N64() ? Mips::T9_64 : Mips::T9;
unsigned ZERO = STI.isABI_N64() ? Mips::ZERO_64 : Mips::ZERO;
unsigned OffsetReg = I->getOperand(0).getReg();
unsigned TargetReg = I->getOperand(1).getReg();
// addu $ra, $v0, $zero
// addu $sp, $sp, $v1
// jr $ra
if (TM.getRelocationModel() == Reloc::PIC_)
BuildMI(MBB, I, I->getDebugLoc(), TM.getInstrInfo()->get(ADDU), T9)
.addReg(TargetReg).addReg(ZERO);
BuildMI(MBB, I, I->getDebugLoc(), TM.getInstrInfo()->get(ADDU), RA)
.addReg(TargetReg).addReg(ZERO);
BuildMI(MBB, I, I->getDebugLoc(), TM.getInstrInfo()->get(ADDU), SP)
.addReg(SP).addReg(OffsetReg);
BuildMI(MBB, I, I->getDebugLoc(), TM.getInstrInfo()->get(JR)).addReg(RA);
}
const MipsInstrInfo *llvm::createMipsSEInstrInfo(MipsTargetMachine &TM) {
return new MipsSEInstrInfo(TM);
}