X86RegisterInfo.cpp [plain text]
#include "X86RegisterInfo.h"
#include "X86FrameLowering.h"
#include "X86InstrBuilder.h"
#include "X86MachineFunctionInfo.h"
#include "X86Subtarget.h"
#include "X86TargetMachine.h"
#include "llvm/ADT/BitVector.h"
#include "llvm/ADT/STLExtras.h"
#include "llvm/CodeGen/MachineFrameInfo.h"
#include "llvm/CodeGen/MachineFunction.h"
#include "llvm/CodeGen/MachineFunctionPass.h"
#include "llvm/CodeGen/MachineInstrBuilder.h"
#include "llvm/CodeGen/MachineModuleInfo.h"
#include "llvm/CodeGen/MachineRegisterInfo.h"
#include "llvm/IR/Constants.h"
#include "llvm/IR/Function.h"
#include "llvm/IR/Type.h"
#include "llvm/MC/MCAsmInfo.h"
#include "llvm/Support/CommandLine.h"
#include "llvm/Support/ErrorHandling.h"
#include "llvm/Target/TargetFrameLowering.h"
#include "llvm/Target/TargetInstrInfo.h"
#include "llvm/Target/TargetMachine.h"
#include "llvm/Target/TargetOptions.h"
using namespace llvm;
#define GET_REGINFO_TARGET_DESC
#include "X86GenRegisterInfo.inc"
static cl::opt<bool>
EnableBasePointer("x86-use-base-pointer", cl::Hidden, cl::init(true),
cl::desc("Enable use of a base pointer for complex stack frames"));
X86RegisterInfo::X86RegisterInfo(const Triple &TT)
: X86GenRegisterInfo((TT.isArch64Bit() ? X86::RIP : X86::EIP),
X86_MC::getDwarfRegFlavour(TT, false),
X86_MC::getDwarfRegFlavour(TT, true),
(TT.isArch64Bit() ? X86::RIP : X86::EIP)) {
X86_MC::InitLLVM2SEHRegisterMapping(this);
Is64Bit = TT.isArch64Bit();
IsWin64 = Is64Bit && TT.isOSWindows();
if (Is64Bit) {
SlotSize = 8;
bool Use64BitReg = TT.getEnvironment() != Triple::GNUX32;
StackPtr = Use64BitReg ? X86::RSP : X86::ESP;
FramePtr = Use64BitReg ? X86::RBP : X86::EBP;
BasePtr = Use64BitReg ? X86::RBX : X86::EBX;
} else {
SlotSize = 4;
StackPtr = X86::ESP;
FramePtr = X86::EBP;
BasePtr = X86::ESI;
}
}
bool
X86RegisterInfo::trackLivenessAfterRegAlloc(const MachineFunction &MF) const {
return true;
}
int
X86RegisterInfo::getSEHRegNum(unsigned i) const {
return getEncodingValue(i);
}
const TargetRegisterClass *
X86RegisterInfo::getSubClassWithSubReg(const TargetRegisterClass *RC,
unsigned Idx) const {
if (!Is64Bit && Idx == X86::sub_8bit)
Idx = X86::sub_8bit_hi;
return X86GenRegisterInfo::getSubClassWithSubReg(RC, Idx);
}
const TargetRegisterClass *
X86RegisterInfo::getMatchingSuperRegClass(const TargetRegisterClass *A,
const TargetRegisterClass *B,
unsigned SubIdx) const {
if (!Is64Bit && SubIdx == X86::sub_8bit) {
A = X86GenRegisterInfo::getSubClassWithSubReg(A, X86::sub_8bit_hi);
if (!A)
return nullptr;
}
return X86GenRegisterInfo::getMatchingSuperRegClass(A, B, SubIdx);
}
const TargetRegisterClass *
X86RegisterInfo::getLargestLegalSuperClass(const TargetRegisterClass *RC,
const MachineFunction &MF) const {
if (RC == &X86::GR8_NOREXRegClass)
return RC;
const TargetRegisterClass *Super = RC;
TargetRegisterClass::sc_iterator I = RC->getSuperClasses();
do {
switch (Super->getID()) {
case X86::GR8RegClassID:
case X86::GR16RegClassID:
case X86::GR32RegClassID:
case X86::GR64RegClassID:
case X86::FR32RegClassID:
case X86::FR64RegClassID:
case X86::RFP32RegClassID:
case X86::RFP64RegClassID:
case X86::RFP80RegClassID:
case X86::VR128RegClassID:
case X86::VR256RegClassID:
if (Super->getSize() == RC->getSize())
return Super;
}
Super = *I++;
} while (Super);
return RC;
}
const TargetRegisterClass *
X86RegisterInfo::getPointerRegClass(const MachineFunction &MF,
unsigned Kind) const {
const X86Subtarget &Subtarget = MF.getSubtarget<X86Subtarget>();
switch (Kind) {
default: llvm_unreachable("Unexpected Kind in getPointerRegClass!");
case 0: if (Subtarget.isTarget64BitLP64())
return &X86::GR64RegClass;
return &X86::GR32RegClass;
case 1: if (Subtarget.isTarget64BitLP64())
return &X86::GR64_NOSPRegClass;
return &X86::GR32_NOSPRegClass;
case 2: if (Subtarget.isTarget64BitLP64())
return &X86::GR64_NOREXRegClass;
return &X86::GR32_NOREXRegClass;
case 3: if (Subtarget.isTarget64BitLP64())
return &X86::GR64_NOREX_NOSPRegClass;
return &X86::GR32_NOREX_NOSPRegClass;
case 4: return getGPRsForTailCall(MF);
}
}
const TargetRegisterClass *
X86RegisterInfo::getGPRsForTailCall(const MachineFunction &MF) const {
const Function *F = MF.getFunction();
if (IsWin64 || (F && F->getCallingConv() == CallingConv::X86_64_Win64))
return &X86::GR64_TCW64RegClass;
else if (Is64Bit)
return &X86::GR64_TCRegClass;
bool hasHipeCC = (F ? F->getCallingConv() == CallingConv::HiPE : false);
if (hasHipeCC)
return &X86::GR32RegClass;
return &X86::GR32_TCRegClass;
}
const TargetRegisterClass *
X86RegisterInfo::getCrossCopyRegClass(const TargetRegisterClass *RC) const {
if (RC == &X86::CCRRegClass) {
if (Is64Bit)
return &X86::GR64RegClass;
else
return &X86::GR32RegClass;
}
return RC;
}
unsigned
X86RegisterInfo::getRegPressureLimit(const TargetRegisterClass *RC,
MachineFunction &MF) const {
const X86FrameLowering *TFI = getFrameLowering(MF);
unsigned FPDiff = TFI->hasFP(MF) ? 1 : 0;
switch (RC->getID()) {
default:
return 0;
case X86::GR32RegClassID:
return 4 - FPDiff;
case X86::GR64RegClassID:
return 12 - FPDiff;
case X86::VR128RegClassID:
return Is64Bit ? 10 : 4;
case X86::VR64RegClassID:
return 4;
}
}
const MCPhysReg *
X86RegisterInfo::getCalleeSavedRegs(const MachineFunction *MF) const {
const X86Subtarget &Subtarget = MF->getSubtarget<X86Subtarget>();
bool HasSSE = Subtarget.hasSSE1();
bool HasAVX = Subtarget.hasAVX();
bool HasAVX512 = Subtarget.hasAVX512();
bool CallsEHReturn = MF->getMMI().callsEHReturn();
assert(MF && "MachineFunction required");
switch (MF->getFunction()->getCallingConv()) {
case CallingConv::GHC:
case CallingConv::HiPE:
return CSR_NoRegs_SaveList;
case CallingConv::AnyReg:
if (HasAVX)
return CSR_64_AllRegs_AVX_SaveList;
return CSR_64_AllRegs_SaveList;
case CallingConv::PreserveMost:
return CSR_64_RT_MostRegs_SaveList;
case CallingConv::PreserveAll:
if (HasAVX)
return CSR_64_RT_AllRegs_AVX_SaveList;
return CSR_64_RT_AllRegs_SaveList;
case CallingConv::CXX_FAST_TLS:
if (Is64Bit)
return MF->getInfo<X86MachineFunctionInfo>()->isSplitCSR() ?
CSR_64_CXX_TLS_Darwin_PE_SaveList : CSR_64_TLS_Darwin_SaveList;
break;
case CallingConv::Intel_OCL_BI: {
if (HasAVX512 && IsWin64)
return CSR_Win64_Intel_OCL_BI_AVX512_SaveList;
if (HasAVX512 && Is64Bit)
return CSR_64_Intel_OCL_BI_AVX512_SaveList;
if (HasAVX && IsWin64)
return CSR_Win64_Intel_OCL_BI_AVX_SaveList;
if (HasAVX && Is64Bit)
return CSR_64_Intel_OCL_BI_AVX_SaveList;
if (!HasAVX && !IsWin64 && Is64Bit)
return CSR_64_Intel_OCL_BI_SaveList;
break;
}
case CallingConv::HHVM:
return CSR_64_HHVM_SaveList;
case CallingConv::Cold:
if (Is64Bit)
return CSR_64_MostRegs_SaveList;
break;
case CallingConv::X86_64_Win64:
return CSR_Win64_SaveList;
case CallingConv::X86_64_SysV:
if (CallsEHReturn)
return CSR_64EHRet_SaveList;
return CSR_64_SaveList;
case CallingConv::X86_INTR:
if (Is64Bit) {
if (HasAVX)
return CSR_64_AllRegs_AVX_SaveList;
else
return CSR_64_AllRegs_SaveList;
} else {
if (HasSSE)
return CSR_32_AllRegs_SSE_SaveList;
else
return CSR_32_AllRegs_SaveList;
}
default:
break;
}
if (Is64Bit) {
if (IsWin64)
return CSR_Win64_SaveList;
if (CallsEHReturn)
return CSR_64EHRet_SaveList;
if (Subtarget.getTargetLowering()->supportSwiftError() &&
MF->getFunction()->getAttributes().hasAttrSomewhere(
Attribute::SwiftError))
return CSR_64_SwiftError_SaveList;
return CSR_64_SaveList;
}
if (CallsEHReturn)
return CSR_32EHRet_SaveList;
return CSR_32_SaveList;
}
const MCPhysReg *X86RegisterInfo::getCalleeSavedRegsViaCopy(
const MachineFunction *MF) const {
assert(MF && "Invalid MachineFunction pointer.");
if (MF->getFunction()->getCallingConv() == CallingConv::CXX_FAST_TLS &&
MF->getInfo<X86MachineFunctionInfo>()->isSplitCSR())
return CSR_64_CXX_TLS_Darwin_ViaCopy_SaveList;
return nullptr;
}
const uint32_t *
X86RegisterInfo::getCallPreservedMask(const MachineFunction &MF,
CallingConv::ID CC) const {
const X86Subtarget &Subtarget = MF.getSubtarget<X86Subtarget>();
bool HasSSE = Subtarget.hasSSE1();
bool HasAVX = Subtarget.hasAVX();
bool HasAVX512 = Subtarget.hasAVX512();
switch (CC) {
case CallingConv::GHC:
case CallingConv::HiPE:
return CSR_NoRegs_RegMask;
case CallingConv::AnyReg:
if (HasAVX)
return CSR_64_AllRegs_AVX_RegMask;
return CSR_64_AllRegs_RegMask;
case CallingConv::PreserveMost:
return CSR_64_RT_MostRegs_RegMask;
case CallingConv::PreserveAll:
if (HasAVX)
return CSR_64_RT_AllRegs_AVX_RegMask;
return CSR_64_RT_AllRegs_RegMask;
case CallingConv::CXX_FAST_TLS:
if (Is64Bit)
return CSR_64_TLS_Darwin_RegMask;
break;
case CallingConv::Intel_OCL_BI: {
if (HasAVX512 && IsWin64)
return CSR_Win64_Intel_OCL_BI_AVX512_RegMask;
if (HasAVX512 && Is64Bit)
return CSR_64_Intel_OCL_BI_AVX512_RegMask;
if (HasAVX && IsWin64)
return CSR_Win64_Intel_OCL_BI_AVX_RegMask;
if (HasAVX && Is64Bit)
return CSR_64_Intel_OCL_BI_AVX_RegMask;
if (!HasAVX && !IsWin64 && Is64Bit)
return CSR_64_Intel_OCL_BI_RegMask;
break;
}
case CallingConv::HHVM:
return CSR_64_HHVM_RegMask;
case CallingConv::Cold:
if (Is64Bit)
return CSR_64_MostRegs_RegMask;
break;
case CallingConv::X86_64_Win64:
return CSR_Win64_RegMask;
case CallingConv::X86_64_SysV:
return CSR_64_RegMask;
case CallingConv::X86_INTR:
if (Is64Bit) {
if (HasAVX)
return CSR_64_AllRegs_AVX_RegMask;
else
return CSR_64_AllRegs_RegMask;
} else {
if (HasSSE)
return CSR_32_AllRegs_SSE_RegMask;
else
return CSR_32_AllRegs_RegMask;
}
default:
break;
}
if (Is64Bit) {
if (IsWin64)
return CSR_Win64_RegMask;
if (Subtarget.getTargetLowering()->supportSwiftError() &&
MF.getFunction()->getAttributes().hasAttrSomewhere(
Attribute::SwiftError))
return CSR_64_SwiftError_RegMask;
return CSR_64_RegMask;
}
return CSR_32_RegMask;
}
const uint32_t*
X86RegisterInfo::getNoPreservedMask() const {
return CSR_NoRegs_RegMask;
}
const uint32_t *X86RegisterInfo::getDarwinTLSCallPreservedMask() const {
return CSR_64_TLS_Darwin_RegMask;
}
BitVector X86RegisterInfo::getReservedRegs(const MachineFunction &MF) const {
BitVector Reserved(getNumRegs());
const X86FrameLowering *TFI = getFrameLowering(MF);
for (MCSubRegIterator I(X86::RSP, this, true); I.isValid();
++I)
Reserved.set(*I);
for (MCSubRegIterator I(X86::RIP, this, true); I.isValid();
++I)
Reserved.set(*I);
if (TFI->hasFP(MF)) {
for (MCSubRegIterator I(X86::RBP, this, true); I.isValid();
++I)
Reserved.set(*I);
}
if (hasBasePointer(MF)) {
CallingConv::ID CC = MF.getFunction()->getCallingConv();
const uint32_t *RegMask = getCallPreservedMask(MF, CC);
if (MachineOperand::clobbersPhysReg(RegMask, getBaseRegister()))
report_fatal_error(
"Stack realignment in presence of dynamic allocas is not supported with"
"this calling convention.");
unsigned BasePtr = getX86SubSuperRegister(getBaseRegister(), 64);
for (MCSubRegIterator I(BasePtr, this, true);
I.isValid(); ++I)
Reserved.set(*I);
}
Reserved.set(X86::CS);
Reserved.set(X86::SS);
Reserved.set(X86::DS);
Reserved.set(X86::ES);
Reserved.set(X86::FS);
Reserved.set(X86::GS);
for (unsigned n = 0; n != 8; ++n)
Reserved.set(X86::ST0 + n);
if (!Is64Bit) {
Reserved.set(X86::SIL);
Reserved.set(X86::DIL);
Reserved.set(X86::BPL);
Reserved.set(X86::SPL);
for (unsigned n = 0; n != 8; ++n) {
for (MCRegAliasIterator AI(X86::R8 + n, this, true); AI.isValid(); ++AI)
Reserved.set(*AI);
for (MCRegAliasIterator AI(X86::XMM8 + n, this, true); AI.isValid(); ++AI)
Reserved.set(*AI);
}
}
if (!Is64Bit || !MF.getSubtarget<X86Subtarget>().hasAVX512()) {
for (unsigned n = 16; n != 32; ++n) {
for (MCRegAliasIterator AI(X86::XMM0 + n, this, true); AI.isValid(); ++AI)
Reserved.set(*AI);
}
}
return Reserved;
}
void X86RegisterInfo::adjustStackMapLiveOutMask(uint32_t *Mask) const {
assert(!(Mask[X86::EFLAGS / 32] & (1U << (X86::EFLAGS % 32))) &&
"EFLAGS are not live-out from a patchpoint.");
for (auto Reg : {X86::EFLAGS, X86::RIP, X86::EIP, X86::IP})
Mask[Reg / 32] &= ~(1U << (Reg % 32));
}
static bool CantUseSP(const MachineFrameInfo *MFI) {
return MFI->hasVarSizedObjects() || MFI->hasOpaqueSPAdjustment();
}
bool X86RegisterInfo::hasBasePointer(const MachineFunction &MF) const {
const MachineFrameInfo *MFI = MF.getFrameInfo();
if (!EnableBasePointer)
return false;
bool CantUseFP = needsStackRealignment(MF);
return CantUseFP && CantUseSP(MFI);
}
bool X86RegisterInfo::canRealignStack(const MachineFunction &MF) const {
if (!TargetRegisterInfo::canRealignStack(MF))
return false;
const MachineFrameInfo *MFI = MF.getFrameInfo();
const MachineRegisterInfo *MRI = &MF.getRegInfo();
if (!MRI->canReserveReg(FramePtr))
return false;
if (CantUseSP(MFI))
return MRI->canReserveReg(BasePtr);
return true;
}
bool X86RegisterInfo::hasReservedSpillSlot(const MachineFunction &MF,
unsigned Reg, int &FrameIdx) const {
llvm_unreachable("Unused function on X86. Otherwise need a test case.");
}
void
X86RegisterInfo::eliminateFrameIndex(MachineBasicBlock::iterator II,
int SPAdj, unsigned FIOperandNum,
RegScavenger *RS) const {
MachineInstr &MI = *II;
MachineFunction &MF = *MI.getParent()->getParent();
const X86FrameLowering *TFI = getFrameLowering(MF);
int FrameIndex = MI.getOperand(FIOperandNum).getIndex();
unsigned BasePtr;
unsigned Opc = MI.getOpcode();
bool AfterFPPop = Opc == X86::TAILJMPm64 || Opc == X86::TAILJMPm ||
Opc == X86::TCRETURNmi || Opc == X86::TCRETURNmi64;
if (hasBasePointer(MF))
BasePtr = (FrameIndex < 0 ? FramePtr : getBaseRegister());
else if (needsStackRealignment(MF))
BasePtr = (FrameIndex < 0 ? FramePtr : StackPtr);
else if (AfterFPPop)
BasePtr = StackPtr;
else
BasePtr = (TFI->hasFP(MF) ? FramePtr : StackPtr);
unsigned IgnoredFrameReg;
if (Opc == TargetOpcode::LOCAL_ESCAPE) {
MachineOperand &FI = MI.getOperand(FIOperandNum);
int Offset;
Offset = TFI->getFrameIndexReference(MF, FrameIndex, IgnoredFrameReg);
FI.ChangeToImmediate(Offset);
return;
}
if (Opc == X86::LEA64_32r && X86::GR32RegClass.contains(BasePtr))
BasePtr = getX86SubSuperRegister(BasePtr, 64);
MI.getOperand(FIOperandNum).ChangeToRegister(BasePtr, false);
int FIOffset;
if (AfterFPPop) {
const MachineFrameInfo *MFI = MF.getFrameInfo();
FIOffset = MFI->getObjectOffset(FrameIndex) - TFI->getOffsetOfLocalArea();
} else
FIOffset = TFI->getFrameIndexReference(MF, FrameIndex, IgnoredFrameReg);
if (BasePtr == StackPtr)
FIOffset += SPAdj;
if (Opc == TargetOpcode::STACKMAP || Opc == TargetOpcode::PATCHPOINT) {
assert(BasePtr == FramePtr && "Expected the FP as base register");
int64_t Offset = MI.getOperand(FIOperandNum + 1).getImm() + FIOffset;
MI.getOperand(FIOperandNum + 1).ChangeToImmediate(Offset);
return;
}
if (MI.getOperand(FIOperandNum+3).isImm()) {
int Imm = (int)(MI.getOperand(FIOperandNum + 3).getImm());
int Offset = FIOffset + Imm;
assert((!Is64Bit || isInt<32>((long long)FIOffset + Imm)) &&
"Requesting 64-bit offset in 32-bit immediate!");
MI.getOperand(FIOperandNum + 3).ChangeToImmediate(Offset);
} else {
uint64_t Offset = FIOffset +
(uint64_t)MI.getOperand(FIOperandNum+3).getOffset();
MI.getOperand(FIOperandNum + 3).setOffset(Offset);
}
}
unsigned X86RegisterInfo::getFrameRegister(const MachineFunction &MF) const {
const X86FrameLowering *TFI = getFrameLowering(MF);
return TFI->hasFP(MF) ? FramePtr : StackPtr;
}
unsigned
X86RegisterInfo::getPtrSizedFrameRegister(const MachineFunction &MF) const {
const X86Subtarget &Subtarget = MF.getSubtarget<X86Subtarget>();
unsigned FrameReg = getFrameRegister(MF);
if (Subtarget.isTarget64BitILP32())
FrameReg = getX86SubSuperRegister(FrameReg, 32);
return FrameReg;
}
unsigned llvm::get512BitSuperRegister(unsigned Reg) {
if (Reg >= X86::XMM0 && Reg <= X86::XMM31)
return X86::ZMM0 + (Reg - X86::XMM0);
if (Reg >= X86::YMM0 && Reg <= X86::YMM31)
return X86::ZMM0 + (Reg - X86::YMM0);
if (Reg >= X86::ZMM0 && Reg <= X86::ZMM31)
return Reg;
llvm_unreachable("Unexpected SIMD register");
}