llvm-6502/lib/Target/X86/X86MCInstLower.cpp
Sanjoy Das a4b0d863f9 [ImplicitNullChecks] Work with implicit defs.
Summary:
This change generalizes the implicit null checks pass to work with
instructions that don't have any explicit register defs.  This lets us
use X86's `cmp` against memory as faulting load instructions.

Reviewers: reames, JosephTremoulet

Subscribers: llvm-commits

Differential Revision: http://reviews.llvm.org/D11286

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@242703 91177308-0d34-0410-b5e6-96231b3b80d8
2015-07-20 20:31:39 +00:00

1344 lines
50 KiB
C++

//===-- X86MCInstLower.cpp - Convert X86 MachineInstr to an MCInst --------===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This file contains code to lower X86 MachineInstrs to their corresponding
// MCInst records.
//
//===----------------------------------------------------------------------===//
#include "X86AsmPrinter.h"
#include "X86RegisterInfo.h"
#include "InstPrinter/X86ATTInstPrinter.h"
#include "MCTargetDesc/X86BaseInfo.h"
#include "Utils/X86ShuffleDecode.h"
#include "llvm/ADT/Optional.h"
#include "llvm/ADT/SmallString.h"
#include "llvm/CodeGen/MachineFunction.h"
#include "llvm/CodeGen/MachineConstantPool.h"
#include "llvm/CodeGen/MachineOperand.h"
#include "llvm/CodeGen/MachineModuleInfoImpls.h"
#include "llvm/CodeGen/StackMaps.h"
#include "llvm/IR/DataLayout.h"
#include "llvm/IR/GlobalValue.h"
#include "llvm/IR/Mangler.h"
#include "llvm/MC/MCAsmInfo.h"
#include "llvm/MC/MCCodeEmitter.h"
#include "llvm/MC/MCContext.h"
#include "llvm/MC/MCExpr.h"
#include "llvm/MC/MCFixup.h"
#include "llvm/MC/MCInst.h"
#include "llvm/MC/MCInstBuilder.h"
#include "llvm/MC/MCStreamer.h"
#include "llvm/MC/MCSymbol.h"
#include "llvm/Support/TargetRegistry.h"
using namespace llvm;
namespace {
/// X86MCInstLower - This class is used to lower an MachineInstr into an MCInst.
class X86MCInstLower {
MCContext &Ctx;
const MachineFunction &MF;
const TargetMachine &TM;
const MCAsmInfo &MAI;
X86AsmPrinter &AsmPrinter;
public:
X86MCInstLower(const MachineFunction &MF, X86AsmPrinter &asmprinter);
Optional<MCOperand> LowerMachineOperand(const MachineInstr *MI,
const MachineOperand &MO) const;
void Lower(const MachineInstr *MI, MCInst &OutMI) const;
MCSymbol *GetSymbolFromOperand(const MachineOperand &MO) const;
MCOperand LowerSymbolOperand(const MachineOperand &MO, MCSymbol *Sym) const;
private:
MachineModuleInfoMachO &getMachOMMI() const;
Mangler *getMang() const {
return AsmPrinter.Mang;
}
};
} // end anonymous namespace
// Emit a minimal sequence of nops spanning NumBytes bytes.
static void EmitNops(MCStreamer &OS, unsigned NumBytes, bool Is64Bit,
const MCSubtargetInfo &STI);
namespace llvm {
X86AsmPrinter::StackMapShadowTracker::StackMapShadowTracker(TargetMachine &TM)
: TM(TM), InShadow(false), RequiredShadowSize(0), CurrentShadowSize(0) {}
X86AsmPrinter::StackMapShadowTracker::~StackMapShadowTracker() {}
void
X86AsmPrinter::StackMapShadowTracker::startFunction(MachineFunction &F) {
MF = &F;
CodeEmitter.reset(TM.getTarget().createMCCodeEmitter(
*MF->getSubtarget().getInstrInfo(),
*MF->getSubtarget().getRegisterInfo(), MF->getContext()));
}
void X86AsmPrinter::StackMapShadowTracker::count(MCInst &Inst,
const MCSubtargetInfo &STI) {
if (InShadow) {
SmallString<256> Code;
SmallVector<MCFixup, 4> Fixups;
raw_svector_ostream VecOS(Code);
CodeEmitter->encodeInstruction(Inst, VecOS, Fixups, STI);
VecOS.flush();
CurrentShadowSize += Code.size();
if (CurrentShadowSize >= RequiredShadowSize)
InShadow = false; // The shadow is big enough. Stop counting.
}
}
void X86AsmPrinter::StackMapShadowTracker::emitShadowPadding(
MCStreamer &OutStreamer, const MCSubtargetInfo &STI) {
if (InShadow && CurrentShadowSize < RequiredShadowSize) {
InShadow = false;
EmitNops(OutStreamer, RequiredShadowSize - CurrentShadowSize,
MF->getSubtarget<X86Subtarget>().is64Bit(), STI);
}
}
void X86AsmPrinter::EmitAndCountInstruction(MCInst &Inst) {
OutStreamer->EmitInstruction(Inst, getSubtargetInfo());
SMShadowTracker.count(Inst, getSubtargetInfo());
}
} // end llvm namespace
X86MCInstLower::X86MCInstLower(const MachineFunction &mf,
X86AsmPrinter &asmprinter)
: Ctx(mf.getContext()), MF(mf), TM(mf.getTarget()), MAI(*TM.getMCAsmInfo()),
AsmPrinter(asmprinter) {}
MachineModuleInfoMachO &X86MCInstLower::getMachOMMI() const {
return MF.getMMI().getObjFileInfo<MachineModuleInfoMachO>();
}
/// GetSymbolFromOperand - Lower an MO_GlobalAddress or MO_ExternalSymbol
/// operand to an MCSymbol.
MCSymbol *X86MCInstLower::
GetSymbolFromOperand(const MachineOperand &MO) const {
const DataLayout &DL = MF.getDataLayout();
assert((MO.isGlobal() || MO.isSymbol() || MO.isMBB()) && "Isn't a symbol reference");
MCSymbol *Sym = nullptr;
SmallString<128> Name;
StringRef Suffix;
switch (MO.getTargetFlags()) {
case X86II::MO_DLLIMPORT:
// Handle dllimport linkage.
Name += "__imp_";
break;
case X86II::MO_DARWIN_STUB:
Suffix = "$stub";
break;
case X86II::MO_DARWIN_NONLAZY:
case X86II::MO_DARWIN_NONLAZY_PIC_BASE:
case X86II::MO_DARWIN_HIDDEN_NONLAZY_PIC_BASE:
Suffix = "$non_lazy_ptr";
break;
}
if (!Suffix.empty())
Name += DL.getPrivateGlobalPrefix();
unsigned PrefixLen = Name.size();
if (MO.isGlobal()) {
const GlobalValue *GV = MO.getGlobal();
AsmPrinter.getNameWithPrefix(Name, GV);
} else if (MO.isSymbol()) {
Mangler::getNameWithPrefix(Name, MO.getSymbolName(), DL);
} else if (MO.isMBB()) {
assert(Suffix.empty());
Sym = MO.getMBB()->getSymbol();
}
unsigned OrigLen = Name.size() - PrefixLen;
Name += Suffix;
if (!Sym)
Sym = Ctx.getOrCreateSymbol(Name);
StringRef OrigName = StringRef(Name).substr(PrefixLen, OrigLen);
// If the target flags on the operand changes the name of the symbol, do that
// before we return the symbol.
switch (MO.getTargetFlags()) {
default: break;
case X86II::MO_DARWIN_NONLAZY:
case X86II::MO_DARWIN_NONLAZY_PIC_BASE: {
MachineModuleInfoImpl::StubValueTy &StubSym =
getMachOMMI().getGVStubEntry(Sym);
if (!StubSym.getPointer()) {
assert(MO.isGlobal() && "Extern symbol not handled yet");
StubSym =
MachineModuleInfoImpl::
StubValueTy(AsmPrinter.getSymbol(MO.getGlobal()),
!MO.getGlobal()->hasInternalLinkage());
}
break;
}
case X86II::MO_DARWIN_HIDDEN_NONLAZY_PIC_BASE: {
MachineModuleInfoImpl::StubValueTy &StubSym =
getMachOMMI().getHiddenGVStubEntry(Sym);
if (!StubSym.getPointer()) {
assert(MO.isGlobal() && "Extern symbol not handled yet");
StubSym =
MachineModuleInfoImpl::
StubValueTy(AsmPrinter.getSymbol(MO.getGlobal()),
!MO.getGlobal()->hasInternalLinkage());
}
break;
}
case X86II::MO_DARWIN_STUB: {
MachineModuleInfoImpl::StubValueTy &StubSym =
getMachOMMI().getFnStubEntry(Sym);
if (StubSym.getPointer())
return Sym;
if (MO.isGlobal()) {
StubSym =
MachineModuleInfoImpl::
StubValueTy(AsmPrinter.getSymbol(MO.getGlobal()),
!MO.getGlobal()->hasInternalLinkage());
} else {
StubSym =
MachineModuleInfoImpl::
StubValueTy(Ctx.getOrCreateSymbol(OrigName), false);
}
break;
}
}
return Sym;
}
MCOperand X86MCInstLower::LowerSymbolOperand(const MachineOperand &MO,
MCSymbol *Sym) const {
// FIXME: We would like an efficient form for this, so we don't have to do a
// lot of extra uniquing.
const MCExpr *Expr = nullptr;
MCSymbolRefExpr::VariantKind RefKind = MCSymbolRefExpr::VK_None;
switch (MO.getTargetFlags()) {
default: llvm_unreachable("Unknown target flag on GV operand");
case X86II::MO_NO_FLAG: // No flag.
// These affect the name of the symbol, not any suffix.
case X86II::MO_DARWIN_NONLAZY:
case X86II::MO_DLLIMPORT:
case X86II::MO_DARWIN_STUB:
break;
case X86II::MO_TLVP: RefKind = MCSymbolRefExpr::VK_TLVP; break;
case X86II::MO_TLVP_PIC_BASE:
Expr = MCSymbolRefExpr::create(Sym, MCSymbolRefExpr::VK_TLVP, Ctx);
// Subtract the pic base.
Expr = MCBinaryExpr::createSub(Expr,
MCSymbolRefExpr::create(MF.getPICBaseSymbol(),
Ctx),
Ctx);
break;
case X86II::MO_SECREL: RefKind = MCSymbolRefExpr::VK_SECREL; break;
case X86II::MO_TLSGD: RefKind = MCSymbolRefExpr::VK_TLSGD; break;
case X86II::MO_TLSLD: RefKind = MCSymbolRefExpr::VK_TLSLD; break;
case X86II::MO_TLSLDM: RefKind = MCSymbolRefExpr::VK_TLSLDM; break;
case X86II::MO_GOTTPOFF: RefKind = MCSymbolRefExpr::VK_GOTTPOFF; break;
case X86II::MO_INDNTPOFF: RefKind = MCSymbolRefExpr::VK_INDNTPOFF; break;
case X86II::MO_TPOFF: RefKind = MCSymbolRefExpr::VK_TPOFF; break;
case X86II::MO_DTPOFF: RefKind = MCSymbolRefExpr::VK_DTPOFF; break;
case X86II::MO_NTPOFF: RefKind = MCSymbolRefExpr::VK_NTPOFF; break;
case X86II::MO_GOTNTPOFF: RefKind = MCSymbolRefExpr::VK_GOTNTPOFF; break;
case X86II::MO_GOTPCREL: RefKind = MCSymbolRefExpr::VK_GOTPCREL; break;
case X86II::MO_GOT: RefKind = MCSymbolRefExpr::VK_GOT; break;
case X86II::MO_GOTOFF: RefKind = MCSymbolRefExpr::VK_GOTOFF; break;
case X86II::MO_PLT: RefKind = MCSymbolRefExpr::VK_PLT; break;
case X86II::MO_PIC_BASE_OFFSET:
case X86II::MO_DARWIN_NONLAZY_PIC_BASE:
case X86II::MO_DARWIN_HIDDEN_NONLAZY_PIC_BASE:
Expr = MCSymbolRefExpr::create(Sym, Ctx);
// Subtract the pic base.
Expr = MCBinaryExpr::createSub(Expr,
MCSymbolRefExpr::create(MF.getPICBaseSymbol(), Ctx),
Ctx);
if (MO.isJTI()) {
assert(MAI.doesSetDirectiveSuppressesReloc());
// If .set directive is supported, use it to reduce the number of
// relocations the assembler will generate for differences between
// local labels. This is only safe when the symbols are in the same
// section so we are restricting it to jumptable references.
MCSymbol *Label = Ctx.createTempSymbol();
AsmPrinter.OutStreamer->EmitAssignment(Label, Expr);
Expr = MCSymbolRefExpr::create(Label, Ctx);
}
break;
}
if (!Expr)
Expr = MCSymbolRefExpr::create(Sym, RefKind, Ctx);
if (!MO.isJTI() && !MO.isMBB() && MO.getOffset())
Expr = MCBinaryExpr::createAdd(Expr,
MCConstantExpr::create(MO.getOffset(), Ctx),
Ctx);
return MCOperand::createExpr(Expr);
}
/// \brief Simplify FOO $imm, %{al,ax,eax,rax} to FOO $imm, for instruction with
/// a short fixed-register form.
static void SimplifyShortImmForm(MCInst &Inst, unsigned Opcode) {
unsigned ImmOp = Inst.getNumOperands() - 1;
assert(Inst.getOperand(0).isReg() &&
(Inst.getOperand(ImmOp).isImm() || Inst.getOperand(ImmOp).isExpr()) &&
((Inst.getNumOperands() == 3 && Inst.getOperand(1).isReg() &&
Inst.getOperand(0).getReg() == Inst.getOperand(1).getReg()) ||
Inst.getNumOperands() == 2) && "Unexpected instruction!");
// Check whether the destination register can be fixed.
unsigned Reg = Inst.getOperand(0).getReg();
if (Reg != X86::AL && Reg != X86::AX && Reg != X86::EAX && Reg != X86::RAX)
return;
// If so, rewrite the instruction.
MCOperand Saved = Inst.getOperand(ImmOp);
Inst = MCInst();
Inst.setOpcode(Opcode);
Inst.addOperand(Saved);
}
/// \brief If a movsx instruction has a shorter encoding for the used register
/// simplify the instruction to use it instead.
static void SimplifyMOVSX(MCInst &Inst) {
unsigned NewOpcode = 0;
unsigned Op0 = Inst.getOperand(0).getReg(), Op1 = Inst.getOperand(1).getReg();
switch (Inst.getOpcode()) {
default:
llvm_unreachable("Unexpected instruction!");
case X86::MOVSX16rr8: // movsbw %al, %ax --> cbtw
if (Op0 == X86::AX && Op1 == X86::AL)
NewOpcode = X86::CBW;
break;
case X86::MOVSX32rr16: // movswl %ax, %eax --> cwtl
if (Op0 == X86::EAX && Op1 == X86::AX)
NewOpcode = X86::CWDE;
break;
case X86::MOVSX64rr32: // movslq %eax, %rax --> cltq
if (Op0 == X86::RAX && Op1 == X86::EAX)
NewOpcode = X86::CDQE;
break;
}
if (NewOpcode != 0) {
Inst = MCInst();
Inst.setOpcode(NewOpcode);
}
}
/// \brief Simplify things like MOV32rm to MOV32o32a.
static void SimplifyShortMoveForm(X86AsmPrinter &Printer, MCInst &Inst,
unsigned Opcode) {
// Don't make these simplifications in 64-bit mode; other assemblers don't
// perform them because they make the code larger.
if (Printer.getSubtarget().is64Bit())
return;
bool IsStore = Inst.getOperand(0).isReg() && Inst.getOperand(1).isReg();
unsigned AddrBase = IsStore;
unsigned RegOp = IsStore ? 0 : 5;
unsigned AddrOp = AddrBase + 3;
assert(Inst.getNumOperands() == 6 && Inst.getOperand(RegOp).isReg() &&
Inst.getOperand(AddrBase + X86::AddrBaseReg).isReg() &&
Inst.getOperand(AddrBase + X86::AddrScaleAmt).isImm() &&
Inst.getOperand(AddrBase + X86::AddrIndexReg).isReg() &&
Inst.getOperand(AddrBase + X86::AddrSegmentReg).isReg() &&
(Inst.getOperand(AddrOp).isExpr() ||
Inst.getOperand(AddrOp).isImm()) &&
"Unexpected instruction!");
// Check whether the destination register can be fixed.
unsigned Reg = Inst.getOperand(RegOp).getReg();
if (Reg != X86::AL && Reg != X86::AX && Reg != X86::EAX && Reg != X86::RAX)
return;
// Check whether this is an absolute address.
// FIXME: We know TLVP symbol refs aren't, but there should be a better way
// to do this here.
bool Absolute = true;
if (Inst.getOperand(AddrOp).isExpr()) {
const MCExpr *MCE = Inst.getOperand(AddrOp).getExpr();
if (const MCSymbolRefExpr *SRE = dyn_cast<MCSymbolRefExpr>(MCE))
if (SRE->getKind() == MCSymbolRefExpr::VK_TLVP)
Absolute = false;
}
if (Absolute &&
(Inst.getOperand(AddrBase + X86::AddrBaseReg).getReg() != 0 ||
Inst.getOperand(AddrBase + X86::AddrScaleAmt).getImm() != 1 ||
Inst.getOperand(AddrBase + X86::AddrIndexReg).getReg() != 0))
return;
// If so, rewrite the instruction.
MCOperand Saved = Inst.getOperand(AddrOp);
MCOperand Seg = Inst.getOperand(AddrBase + X86::AddrSegmentReg);
Inst = MCInst();
Inst.setOpcode(Opcode);
Inst.addOperand(Saved);
Inst.addOperand(Seg);
}
static unsigned getRetOpcode(const X86Subtarget &Subtarget) {
return Subtarget.is64Bit() ? X86::RETQ : X86::RETL;
}
Optional<MCOperand>
X86MCInstLower::LowerMachineOperand(const MachineInstr *MI,
const MachineOperand &MO) const {
switch (MO.getType()) {
default:
MI->dump();
llvm_unreachable("unknown operand type");
case MachineOperand::MO_Register:
// Ignore all implicit register operands.
if (MO.isImplicit())
return None;
return MCOperand::createReg(MO.getReg());
case MachineOperand::MO_Immediate:
return MCOperand::createImm(MO.getImm());
case MachineOperand::MO_MachineBasicBlock:
case MachineOperand::MO_GlobalAddress:
case MachineOperand::MO_ExternalSymbol:
return LowerSymbolOperand(MO, GetSymbolFromOperand(MO));
case MachineOperand::MO_MCSymbol:
return LowerSymbolOperand(MO, MO.getMCSymbol());
case MachineOperand::MO_JumpTableIndex:
return LowerSymbolOperand(MO, AsmPrinter.GetJTISymbol(MO.getIndex()));
case MachineOperand::MO_ConstantPoolIndex:
return LowerSymbolOperand(MO, AsmPrinter.GetCPISymbol(MO.getIndex()));
case MachineOperand::MO_BlockAddress:
return LowerSymbolOperand(
MO, AsmPrinter.GetBlockAddressSymbol(MO.getBlockAddress()));
case MachineOperand::MO_RegisterMask:
// Ignore call clobbers.
return None;
}
}
void X86MCInstLower::Lower(const MachineInstr *MI, MCInst &OutMI) const {
OutMI.setOpcode(MI->getOpcode());
for (const MachineOperand &MO : MI->operands())
if (auto MaybeMCOp = LowerMachineOperand(MI, MO))
OutMI.addOperand(MaybeMCOp.getValue());
// Handle a few special cases to eliminate operand modifiers.
ReSimplify:
switch (OutMI.getOpcode()) {
case X86::LEA64_32r:
case X86::LEA64r:
case X86::LEA16r:
case X86::LEA32r:
// LEA should have a segment register, but it must be empty.
assert(OutMI.getNumOperands() == 1+X86::AddrNumOperands &&
"Unexpected # of LEA operands");
assert(OutMI.getOperand(1+X86::AddrSegmentReg).getReg() == 0 &&
"LEA has segment specified!");
break;
case X86::MOV32ri64:
OutMI.setOpcode(X86::MOV32ri);
break;
// Commute operands to get a smaller encoding by using VEX.R instead of VEX.B
// if one of the registers is extended, but other isn't.
case X86::VMOVAPDrr:
case X86::VMOVAPDYrr:
case X86::VMOVAPSrr:
case X86::VMOVAPSYrr:
case X86::VMOVDQArr:
case X86::VMOVDQAYrr:
case X86::VMOVDQUrr:
case X86::VMOVDQUYrr:
case X86::VMOVUPDrr:
case X86::VMOVUPDYrr:
case X86::VMOVUPSrr:
case X86::VMOVUPSYrr: {
if (!X86II::isX86_64ExtendedReg(OutMI.getOperand(0).getReg()) &&
X86II::isX86_64ExtendedReg(OutMI.getOperand(1).getReg())) {
unsigned NewOpc;
switch (OutMI.getOpcode()) {
default: llvm_unreachable("Invalid opcode");
case X86::VMOVAPDrr: NewOpc = X86::VMOVAPDrr_REV; break;
case X86::VMOVAPDYrr: NewOpc = X86::VMOVAPDYrr_REV; break;
case X86::VMOVAPSrr: NewOpc = X86::VMOVAPSrr_REV; break;
case X86::VMOVAPSYrr: NewOpc = X86::VMOVAPSYrr_REV; break;
case X86::VMOVDQArr: NewOpc = X86::VMOVDQArr_REV; break;
case X86::VMOVDQAYrr: NewOpc = X86::VMOVDQAYrr_REV; break;
case X86::VMOVDQUrr: NewOpc = X86::VMOVDQUrr_REV; break;
case X86::VMOVDQUYrr: NewOpc = X86::VMOVDQUYrr_REV; break;
case X86::VMOVUPDrr: NewOpc = X86::VMOVUPDrr_REV; break;
case X86::VMOVUPDYrr: NewOpc = X86::VMOVUPDYrr_REV; break;
case X86::VMOVUPSrr: NewOpc = X86::VMOVUPSrr_REV; break;
case X86::VMOVUPSYrr: NewOpc = X86::VMOVUPSYrr_REV; break;
}
OutMI.setOpcode(NewOpc);
}
break;
}
case X86::VMOVSDrr:
case X86::VMOVSSrr: {
if (!X86II::isX86_64ExtendedReg(OutMI.getOperand(0).getReg()) &&
X86II::isX86_64ExtendedReg(OutMI.getOperand(2).getReg())) {
unsigned NewOpc;
switch (OutMI.getOpcode()) {
default: llvm_unreachable("Invalid opcode");
case X86::VMOVSDrr: NewOpc = X86::VMOVSDrr_REV; break;
case X86::VMOVSSrr: NewOpc = X86::VMOVSSrr_REV; break;
}
OutMI.setOpcode(NewOpc);
}
break;
}
// TAILJMPr64, CALL64r, CALL64pcrel32 - These instructions have register
// inputs modeled as normal uses instead of implicit uses. As such, truncate
// off all but the first operand (the callee). FIXME: Change isel.
case X86::TAILJMPr64:
case X86::TAILJMPr64_REX:
case X86::CALL64r:
case X86::CALL64pcrel32: {
unsigned Opcode = OutMI.getOpcode();
MCOperand Saved = OutMI.getOperand(0);
OutMI = MCInst();
OutMI.setOpcode(Opcode);
OutMI.addOperand(Saved);
break;
}
case X86::EH_RETURN:
case X86::EH_RETURN64: {
OutMI = MCInst();
OutMI.setOpcode(getRetOpcode(AsmPrinter.getSubtarget()));
break;
}
// TAILJMPd, TAILJMPd64 - Lower to the correct jump instructions.
case X86::TAILJMPr:
case X86::TAILJMPd:
case X86::TAILJMPd64: {
unsigned Opcode;
switch (OutMI.getOpcode()) {
default: llvm_unreachable("Invalid opcode");
case X86::TAILJMPr: Opcode = X86::JMP32r; break;
case X86::TAILJMPd:
case X86::TAILJMPd64: Opcode = X86::JMP_1; break;
}
MCOperand Saved = OutMI.getOperand(0);
OutMI = MCInst();
OutMI.setOpcode(Opcode);
OutMI.addOperand(Saved);
break;
}
case X86::DEC16r:
case X86::DEC32r:
case X86::INC16r:
case X86::INC32r:
// If we aren't in 64-bit mode we can use the 1-byte inc/dec instructions.
if (!AsmPrinter.getSubtarget().is64Bit()) {
unsigned Opcode;
switch (OutMI.getOpcode()) {
default: llvm_unreachable("Invalid opcode");
case X86::DEC16r: Opcode = X86::DEC16r_alt; break;
case X86::DEC32r: Opcode = X86::DEC32r_alt; break;
case X86::INC16r: Opcode = X86::INC16r_alt; break;
case X86::INC32r: Opcode = X86::INC32r_alt; break;
}
OutMI.setOpcode(Opcode);
}
break;
// These are pseudo-ops for OR to help with the OR->ADD transformation. We do
// this with an ugly goto in case the resultant OR uses EAX and needs the
// short form.
case X86::ADD16rr_DB: OutMI.setOpcode(X86::OR16rr); goto ReSimplify;
case X86::ADD32rr_DB: OutMI.setOpcode(X86::OR32rr); goto ReSimplify;
case X86::ADD64rr_DB: OutMI.setOpcode(X86::OR64rr); goto ReSimplify;
case X86::ADD16ri_DB: OutMI.setOpcode(X86::OR16ri); goto ReSimplify;
case X86::ADD32ri_DB: OutMI.setOpcode(X86::OR32ri); goto ReSimplify;
case X86::ADD64ri32_DB: OutMI.setOpcode(X86::OR64ri32); goto ReSimplify;
case X86::ADD16ri8_DB: OutMI.setOpcode(X86::OR16ri8); goto ReSimplify;
case X86::ADD32ri8_DB: OutMI.setOpcode(X86::OR32ri8); goto ReSimplify;
case X86::ADD64ri8_DB: OutMI.setOpcode(X86::OR64ri8); goto ReSimplify;
// Atomic load and store require a separate pseudo-inst because Acquire
// implies mayStore and Release implies mayLoad; fix these to regular MOV
// instructions here
case X86::ACQUIRE_MOV8rm: OutMI.setOpcode(X86::MOV8rm); goto ReSimplify;
case X86::ACQUIRE_MOV16rm: OutMI.setOpcode(X86::MOV16rm); goto ReSimplify;
case X86::ACQUIRE_MOV32rm: OutMI.setOpcode(X86::MOV32rm); goto ReSimplify;
case X86::ACQUIRE_MOV64rm: OutMI.setOpcode(X86::MOV64rm); goto ReSimplify;
case X86::RELEASE_MOV8mr: OutMI.setOpcode(X86::MOV8mr); goto ReSimplify;
case X86::RELEASE_MOV16mr: OutMI.setOpcode(X86::MOV16mr); goto ReSimplify;
case X86::RELEASE_MOV32mr: OutMI.setOpcode(X86::MOV32mr); goto ReSimplify;
case X86::RELEASE_MOV64mr: OutMI.setOpcode(X86::MOV64mr); goto ReSimplify;
case X86::RELEASE_MOV8mi: OutMI.setOpcode(X86::MOV8mi); goto ReSimplify;
case X86::RELEASE_MOV16mi: OutMI.setOpcode(X86::MOV16mi); goto ReSimplify;
case X86::RELEASE_MOV32mi: OutMI.setOpcode(X86::MOV32mi); goto ReSimplify;
case X86::RELEASE_MOV64mi32: OutMI.setOpcode(X86::MOV64mi32); goto ReSimplify;
case X86::RELEASE_ADD8mi: OutMI.setOpcode(X86::ADD8mi); goto ReSimplify;
case X86::RELEASE_ADD32mi: OutMI.setOpcode(X86::ADD32mi); goto ReSimplify;
case X86::RELEASE_ADD64mi32: OutMI.setOpcode(X86::ADD64mi32); goto ReSimplify;
case X86::RELEASE_AND8mi: OutMI.setOpcode(X86::AND8mi); goto ReSimplify;
case X86::RELEASE_AND32mi: OutMI.setOpcode(X86::AND32mi); goto ReSimplify;
case X86::RELEASE_AND64mi32: OutMI.setOpcode(X86::AND64mi32); goto ReSimplify;
case X86::RELEASE_OR8mi: OutMI.setOpcode(X86::OR8mi); goto ReSimplify;
case X86::RELEASE_OR32mi: OutMI.setOpcode(X86::OR32mi); goto ReSimplify;
case X86::RELEASE_OR64mi32: OutMI.setOpcode(X86::OR64mi32); goto ReSimplify;
case X86::RELEASE_XOR8mi: OutMI.setOpcode(X86::XOR8mi); goto ReSimplify;
case X86::RELEASE_XOR32mi: OutMI.setOpcode(X86::XOR32mi); goto ReSimplify;
case X86::RELEASE_XOR64mi32: OutMI.setOpcode(X86::XOR64mi32); goto ReSimplify;
case X86::RELEASE_INC8m: OutMI.setOpcode(X86::INC8m); goto ReSimplify;
case X86::RELEASE_INC16m: OutMI.setOpcode(X86::INC16m); goto ReSimplify;
case X86::RELEASE_INC32m: OutMI.setOpcode(X86::INC32m); goto ReSimplify;
case X86::RELEASE_INC64m: OutMI.setOpcode(X86::INC64m); goto ReSimplify;
case X86::RELEASE_DEC8m: OutMI.setOpcode(X86::DEC8m); goto ReSimplify;
case X86::RELEASE_DEC16m: OutMI.setOpcode(X86::DEC16m); goto ReSimplify;
case X86::RELEASE_DEC32m: OutMI.setOpcode(X86::DEC32m); goto ReSimplify;
case X86::RELEASE_DEC64m: OutMI.setOpcode(X86::DEC64m); goto ReSimplify;
// We don't currently select the correct instruction form for instructions
// which have a short %eax, etc. form. Handle this by custom lowering, for
// now.
//
// Note, we are currently not handling the following instructions:
// MOV64ao8, MOV64o8a
// XCHG16ar, XCHG32ar, XCHG64ar
case X86::MOV8mr_NOREX:
case X86::MOV8mr: SimplifyShortMoveForm(AsmPrinter, OutMI, X86::MOV8o32a); break;
case X86::MOV8rm_NOREX:
case X86::MOV8rm: SimplifyShortMoveForm(AsmPrinter, OutMI, X86::MOV8ao32); break;
case X86::MOV16mr: SimplifyShortMoveForm(AsmPrinter, OutMI, X86::MOV16o32a); break;
case X86::MOV16rm: SimplifyShortMoveForm(AsmPrinter, OutMI, X86::MOV16ao32); break;
case X86::MOV32mr: SimplifyShortMoveForm(AsmPrinter, OutMI, X86::MOV32o32a); break;
case X86::MOV32rm: SimplifyShortMoveForm(AsmPrinter, OutMI, X86::MOV32ao32); break;
case X86::ADC8ri: SimplifyShortImmForm(OutMI, X86::ADC8i8); break;
case X86::ADC16ri: SimplifyShortImmForm(OutMI, X86::ADC16i16); break;
case X86::ADC32ri: SimplifyShortImmForm(OutMI, X86::ADC32i32); break;
case X86::ADC64ri32: SimplifyShortImmForm(OutMI, X86::ADC64i32); break;
case X86::ADD8ri: SimplifyShortImmForm(OutMI, X86::ADD8i8); break;
case X86::ADD16ri: SimplifyShortImmForm(OutMI, X86::ADD16i16); break;
case X86::ADD32ri: SimplifyShortImmForm(OutMI, X86::ADD32i32); break;
case X86::ADD64ri32: SimplifyShortImmForm(OutMI, X86::ADD64i32); break;
case X86::AND8ri: SimplifyShortImmForm(OutMI, X86::AND8i8); break;
case X86::AND16ri: SimplifyShortImmForm(OutMI, X86::AND16i16); break;
case X86::AND32ri: SimplifyShortImmForm(OutMI, X86::AND32i32); break;
case X86::AND64ri32: SimplifyShortImmForm(OutMI, X86::AND64i32); break;
case X86::CMP8ri: SimplifyShortImmForm(OutMI, X86::CMP8i8); break;
case X86::CMP16ri: SimplifyShortImmForm(OutMI, X86::CMP16i16); break;
case X86::CMP32ri: SimplifyShortImmForm(OutMI, X86::CMP32i32); break;
case X86::CMP64ri32: SimplifyShortImmForm(OutMI, X86::CMP64i32); break;
case X86::OR8ri: SimplifyShortImmForm(OutMI, X86::OR8i8); break;
case X86::OR16ri: SimplifyShortImmForm(OutMI, X86::OR16i16); break;
case X86::OR32ri: SimplifyShortImmForm(OutMI, X86::OR32i32); break;
case X86::OR64ri32: SimplifyShortImmForm(OutMI, X86::OR64i32); break;
case X86::SBB8ri: SimplifyShortImmForm(OutMI, X86::SBB8i8); break;
case X86::SBB16ri: SimplifyShortImmForm(OutMI, X86::SBB16i16); break;
case X86::SBB32ri: SimplifyShortImmForm(OutMI, X86::SBB32i32); break;
case X86::SBB64ri32: SimplifyShortImmForm(OutMI, X86::SBB64i32); break;
case X86::SUB8ri: SimplifyShortImmForm(OutMI, X86::SUB8i8); break;
case X86::SUB16ri: SimplifyShortImmForm(OutMI, X86::SUB16i16); break;
case X86::SUB32ri: SimplifyShortImmForm(OutMI, X86::SUB32i32); break;
case X86::SUB64ri32: SimplifyShortImmForm(OutMI, X86::SUB64i32); break;
case X86::TEST8ri: SimplifyShortImmForm(OutMI, X86::TEST8i8); break;
case X86::TEST16ri: SimplifyShortImmForm(OutMI, X86::TEST16i16); break;
case X86::TEST32ri: SimplifyShortImmForm(OutMI, X86::TEST32i32); break;
case X86::TEST64ri32: SimplifyShortImmForm(OutMI, X86::TEST64i32); break;
case X86::XOR8ri: SimplifyShortImmForm(OutMI, X86::XOR8i8); break;
case X86::XOR16ri: SimplifyShortImmForm(OutMI, X86::XOR16i16); break;
case X86::XOR32ri: SimplifyShortImmForm(OutMI, X86::XOR32i32); break;
case X86::XOR64ri32: SimplifyShortImmForm(OutMI, X86::XOR64i32); break;
// Try to shrink some forms of movsx.
case X86::MOVSX16rr8:
case X86::MOVSX32rr16:
case X86::MOVSX64rr32:
SimplifyMOVSX(OutMI);
break;
}
}
void X86AsmPrinter::LowerTlsAddr(X86MCInstLower &MCInstLowering,
const MachineInstr &MI) {
bool is64Bits = MI.getOpcode() == X86::TLS_addr64 ||
MI.getOpcode() == X86::TLS_base_addr64;
bool needsPadding = MI.getOpcode() == X86::TLS_addr64;
MCContext &context = OutStreamer->getContext();
if (needsPadding)
EmitAndCountInstruction(MCInstBuilder(X86::DATA16_PREFIX));
MCSymbolRefExpr::VariantKind SRVK;
switch (MI.getOpcode()) {
case X86::TLS_addr32:
case X86::TLS_addr64:
SRVK = MCSymbolRefExpr::VK_TLSGD;
break;
case X86::TLS_base_addr32:
SRVK = MCSymbolRefExpr::VK_TLSLDM;
break;
case X86::TLS_base_addr64:
SRVK = MCSymbolRefExpr::VK_TLSLD;
break;
default:
llvm_unreachable("unexpected opcode");
}
MCSymbol *sym = MCInstLowering.GetSymbolFromOperand(MI.getOperand(3));
const MCSymbolRefExpr *symRef = MCSymbolRefExpr::create(sym, SRVK, context);
MCInst LEA;
if (is64Bits) {
LEA.setOpcode(X86::LEA64r);
LEA.addOperand(MCOperand::createReg(X86::RDI)); // dest
LEA.addOperand(MCOperand::createReg(X86::RIP)); // base
LEA.addOperand(MCOperand::createImm(1)); // scale
LEA.addOperand(MCOperand::createReg(0)); // index
LEA.addOperand(MCOperand::createExpr(symRef)); // disp
LEA.addOperand(MCOperand::createReg(0)); // seg
} else if (SRVK == MCSymbolRefExpr::VK_TLSLDM) {
LEA.setOpcode(X86::LEA32r);
LEA.addOperand(MCOperand::createReg(X86::EAX)); // dest
LEA.addOperand(MCOperand::createReg(X86::EBX)); // base
LEA.addOperand(MCOperand::createImm(1)); // scale
LEA.addOperand(MCOperand::createReg(0)); // index
LEA.addOperand(MCOperand::createExpr(symRef)); // disp
LEA.addOperand(MCOperand::createReg(0)); // seg
} else {
LEA.setOpcode(X86::LEA32r);
LEA.addOperand(MCOperand::createReg(X86::EAX)); // dest
LEA.addOperand(MCOperand::createReg(0)); // base
LEA.addOperand(MCOperand::createImm(1)); // scale
LEA.addOperand(MCOperand::createReg(X86::EBX)); // index
LEA.addOperand(MCOperand::createExpr(symRef)); // disp
LEA.addOperand(MCOperand::createReg(0)); // seg
}
EmitAndCountInstruction(LEA);
if (needsPadding) {
EmitAndCountInstruction(MCInstBuilder(X86::DATA16_PREFIX));
EmitAndCountInstruction(MCInstBuilder(X86::DATA16_PREFIX));
EmitAndCountInstruction(MCInstBuilder(X86::REX64_PREFIX));
}
StringRef name = is64Bits ? "__tls_get_addr" : "___tls_get_addr";
MCSymbol *tlsGetAddr = context.getOrCreateSymbol(name);
const MCSymbolRefExpr *tlsRef =
MCSymbolRefExpr::create(tlsGetAddr,
MCSymbolRefExpr::VK_PLT,
context);
EmitAndCountInstruction(MCInstBuilder(is64Bits ? X86::CALL64pcrel32
: X86::CALLpcrel32)
.addExpr(tlsRef));
}
/// \brief Emit the optimal amount of multi-byte nops on X86.
static void EmitNops(MCStreamer &OS, unsigned NumBytes, bool Is64Bit, const MCSubtargetInfo &STI) {
// This works only for 64bit. For 32bit we have to do additional checking if
// the CPU supports multi-byte nops.
assert(Is64Bit && "EmitNops only supports X86-64");
while (NumBytes) {
unsigned Opc, BaseReg, ScaleVal, IndexReg, Displacement, SegmentReg;
Opc = IndexReg = Displacement = SegmentReg = 0;
BaseReg = X86::RAX; ScaleVal = 1;
switch (NumBytes) {
case 0: llvm_unreachable("Zero nops?"); break;
case 1: NumBytes -= 1; Opc = X86::NOOP; break;
case 2: NumBytes -= 2; Opc = X86::XCHG16ar; break;
case 3: NumBytes -= 3; Opc = X86::NOOPL; break;
case 4: NumBytes -= 4; Opc = X86::NOOPL; Displacement = 8; break;
case 5: NumBytes -= 5; Opc = X86::NOOPL; Displacement = 8;
IndexReg = X86::RAX; break;
case 6: NumBytes -= 6; Opc = X86::NOOPW; Displacement = 8;
IndexReg = X86::RAX; break;
case 7: NumBytes -= 7; Opc = X86::NOOPL; Displacement = 512; break;
case 8: NumBytes -= 8; Opc = X86::NOOPL; Displacement = 512;
IndexReg = X86::RAX; break;
case 9: NumBytes -= 9; Opc = X86::NOOPW; Displacement = 512;
IndexReg = X86::RAX; break;
default: NumBytes -= 10; Opc = X86::NOOPW; Displacement = 512;
IndexReg = X86::RAX; SegmentReg = X86::CS; break;
}
unsigned NumPrefixes = std::min(NumBytes, 5U);
NumBytes -= NumPrefixes;
for (unsigned i = 0; i != NumPrefixes; ++i)
OS.EmitBytes("\x66");
switch (Opc) {
default: llvm_unreachable("Unexpected opcode"); break;
case X86::NOOP:
OS.EmitInstruction(MCInstBuilder(Opc), STI);
break;
case X86::XCHG16ar:
OS.EmitInstruction(MCInstBuilder(Opc).addReg(X86::AX), STI);
break;
case X86::NOOPL:
case X86::NOOPW:
OS.EmitInstruction(MCInstBuilder(Opc).addReg(BaseReg)
.addImm(ScaleVal).addReg(IndexReg)
.addImm(Displacement).addReg(SegmentReg), STI);
break;
}
} // while (NumBytes)
}
void X86AsmPrinter::LowerSTATEPOINT(const MachineInstr &MI,
X86MCInstLower &MCIL) {
assert(Subtarget->is64Bit() && "Statepoint currently only supports X86-64");
StatepointOpers SOpers(&MI);
if (unsigned PatchBytes = SOpers.getNumPatchBytes()) {
EmitNops(*OutStreamer, PatchBytes, Subtarget->is64Bit(),
getSubtargetInfo());
} else {
// Lower call target and choose correct opcode
const MachineOperand &CallTarget = SOpers.getCallTarget();
MCOperand CallTargetMCOp;
unsigned CallOpcode;
switch (CallTarget.getType()) {
case MachineOperand::MO_GlobalAddress:
case MachineOperand::MO_ExternalSymbol:
CallTargetMCOp = MCIL.LowerSymbolOperand(
CallTarget, MCIL.GetSymbolFromOperand(CallTarget));
CallOpcode = X86::CALL64pcrel32;
// Currently, we only support relative addressing with statepoints.
// Otherwise, we'll need a scratch register to hold the target
// address. You'll fail asserts during load & relocation if this
// symbol is to far away. (TODO: support non-relative addressing)
break;
case MachineOperand::MO_Immediate:
CallTargetMCOp = MCOperand::createImm(CallTarget.getImm());
CallOpcode = X86::CALL64pcrel32;
// Currently, we only support relative addressing with statepoints.
// Otherwise, we'll need a scratch register to hold the target
// immediate. You'll fail asserts during load & relocation if this
// address is to far away. (TODO: support non-relative addressing)
break;
case MachineOperand::MO_Register:
CallTargetMCOp = MCOperand::createReg(CallTarget.getReg());
CallOpcode = X86::CALL64r;
break;
default:
llvm_unreachable("Unsupported operand type in statepoint call target");
break;
}
// Emit call
MCInst CallInst;
CallInst.setOpcode(CallOpcode);
CallInst.addOperand(CallTargetMCOp);
OutStreamer->EmitInstruction(CallInst, getSubtargetInfo());
}
// Record our statepoint node in the same section used by STACKMAP
// and PATCHPOINT
SM.recordStatepoint(MI);
}
void X86AsmPrinter::LowerFAULTING_LOAD_OP(const MachineInstr &MI,
X86MCInstLower &MCIL) {
// FAULTING_LOAD_OP <def>, <handler label>, <load opcode>, <load operands>
unsigned LoadDefRegister = MI.getOperand(0).getReg();
MCSymbol *HandlerLabel = MI.getOperand(1).getMCSymbol();
unsigned LoadOpcode = MI.getOperand(2).getImm();
unsigned LoadOperandsBeginIdx = 3;
FM.recordFaultingOp(FaultMaps::FaultingLoad, HandlerLabel);
MCInst LoadMI;
LoadMI.setOpcode(LoadOpcode);
if (LoadDefRegister != X86::NoRegister)
LoadMI.addOperand(MCOperand::createReg(LoadDefRegister));
for (auto I = MI.operands_begin() + LoadOperandsBeginIdx,
E = MI.operands_end();
I != E; ++I)
if (auto MaybeOperand = MCIL.LowerMachineOperand(&MI, *I))
LoadMI.addOperand(MaybeOperand.getValue());
OutStreamer->EmitInstruction(LoadMI, getSubtargetInfo());
}
// Lower a stackmap of the form:
// <id>, <shadowBytes>, ...
void X86AsmPrinter::LowerSTACKMAP(const MachineInstr &MI) {
SMShadowTracker.emitShadowPadding(*OutStreamer, getSubtargetInfo());
SM.recordStackMap(MI);
unsigned NumShadowBytes = MI.getOperand(1).getImm();
SMShadowTracker.reset(NumShadowBytes);
}
// Lower a patchpoint of the form:
// [<def>], <id>, <numBytes>, <target>, <numArgs>, <cc>, ...
void X86AsmPrinter::LowerPATCHPOINT(const MachineInstr &MI,
X86MCInstLower &MCIL) {
assert(Subtarget->is64Bit() && "Patchpoint currently only supports X86-64");
SMShadowTracker.emitShadowPadding(*OutStreamer, getSubtargetInfo());
SM.recordPatchPoint(MI);
PatchPointOpers opers(&MI);
unsigned ScratchIdx = opers.getNextScratchIdx();
unsigned EncodedBytes = 0;
const MachineOperand &CalleeMO =
opers.getMetaOper(PatchPointOpers::TargetPos);
// Check for null target. If target is non-null (i.e. is non-zero or is
// symbolic) then emit a call.
if (!(CalleeMO.isImm() && !CalleeMO.getImm())) {
MCOperand CalleeMCOp;
switch (CalleeMO.getType()) {
default:
/// FIXME: Add a verifier check for bad callee types.
llvm_unreachable("Unrecognized callee operand type.");
case MachineOperand::MO_Immediate:
if (CalleeMO.getImm())
CalleeMCOp = MCOperand::createImm(CalleeMO.getImm());
break;
case MachineOperand::MO_ExternalSymbol:
case MachineOperand::MO_GlobalAddress:
CalleeMCOp =
MCIL.LowerSymbolOperand(CalleeMO,
MCIL.GetSymbolFromOperand(CalleeMO));
break;
}
// Emit MOV to materialize the target address and the CALL to target.
// This is encoded with 12-13 bytes, depending on which register is used.
unsigned ScratchReg = MI.getOperand(ScratchIdx).getReg();
if (X86II::isX86_64ExtendedReg(ScratchReg))
EncodedBytes = 13;
else
EncodedBytes = 12;
EmitAndCountInstruction(
MCInstBuilder(X86::MOV64ri).addReg(ScratchReg).addOperand(CalleeMCOp));
EmitAndCountInstruction(MCInstBuilder(X86::CALL64r).addReg(ScratchReg));
}
// Emit padding.
unsigned NumBytes = opers.getMetaOper(PatchPointOpers::NBytesPos).getImm();
assert(NumBytes >= EncodedBytes &&
"Patchpoint can't request size less than the length of a call.");
EmitNops(*OutStreamer, NumBytes - EncodedBytes, Subtarget->is64Bit(),
getSubtargetInfo());
}
// Returns instruction preceding MBBI in MachineFunction.
// If MBBI is the first instruction of the first basic block, returns null.
static MachineBasicBlock::const_iterator
PrevCrossBBInst(MachineBasicBlock::const_iterator MBBI) {
const MachineBasicBlock *MBB = MBBI->getParent();
while (MBBI == MBB->begin()) {
if (MBB == MBB->getParent()->begin())
return nullptr;
MBB = MBB->getPrevNode();
MBBI = MBB->end();
}
return --MBBI;
}
static const Constant *getConstantFromPool(const MachineInstr &MI,
const MachineOperand &Op) {
if (!Op.isCPI())
return nullptr;
ArrayRef<MachineConstantPoolEntry> Constants =
MI.getParent()->getParent()->getConstantPool()->getConstants();
const MachineConstantPoolEntry &ConstantEntry =
Constants[Op.getIndex()];
// Bail if this is a machine constant pool entry, we won't be able to dig out
// anything useful.
if (ConstantEntry.isMachineConstantPoolEntry())
return nullptr;
auto *C = dyn_cast<Constant>(ConstantEntry.Val.ConstVal);
assert((!C || ConstantEntry.getType() == C->getType()) &&
"Expected a constant of the same type!");
return C;
}
static std::string getShuffleComment(const MachineOperand &DstOp,
const MachineOperand &SrcOp,
ArrayRef<int> Mask) {
std::string Comment;
// Compute the name for a register. This is really goofy because we have
// multiple instruction printers that could (in theory) use different
// names. Fortunately most people use the ATT style (outside of Windows)
// and they actually agree on register naming here. Ultimately, this is
// a comment, and so its OK if it isn't perfect.
auto GetRegisterName = [](unsigned RegNum) -> StringRef {
return X86ATTInstPrinter::getRegisterName(RegNum);
};
StringRef DstName = DstOp.isReg() ? GetRegisterName(DstOp.getReg()) : "mem";
StringRef SrcName = SrcOp.isReg() ? GetRegisterName(SrcOp.getReg()) : "mem";
raw_string_ostream CS(Comment);
CS << DstName << " = ";
bool NeedComma = false;
bool InSrc = false;
for (int M : Mask) {
// Wrap up any prior entry...
if (M == SM_SentinelZero && InSrc) {
InSrc = false;
CS << "]";
}
if (NeedComma)
CS << ",";
else
NeedComma = true;
// Print this shuffle...
if (M == SM_SentinelZero) {
CS << "zero";
} else {
if (!InSrc) {
InSrc = true;
CS << SrcName << "[";
}
if (M == SM_SentinelUndef)
CS << "u";
else
CS << M;
}
}
if (InSrc)
CS << "]";
CS.flush();
return Comment;
}
void X86AsmPrinter::EmitInstruction(const MachineInstr *MI) {
X86MCInstLower MCInstLowering(*MF, *this);
const X86RegisterInfo *RI = MF->getSubtarget<X86Subtarget>().getRegisterInfo();
switch (MI->getOpcode()) {
case TargetOpcode::DBG_VALUE:
llvm_unreachable("Should be handled target independently");
// Emit nothing here but a comment if we can.
case X86::Int_MemBarrier:
OutStreamer->emitRawComment("MEMBARRIER");
return;
case X86::EH_RETURN:
case X86::EH_RETURN64: {
// Lower these as normal, but add some comments.
unsigned Reg = MI->getOperand(0).getReg();
OutStreamer->AddComment(StringRef("eh_return, addr: %") +
X86ATTInstPrinter::getRegisterName(Reg));
break;
}
case X86::TAILJMPr:
case X86::TAILJMPm:
case X86::TAILJMPd:
case X86::TAILJMPr64:
case X86::TAILJMPm64:
case X86::TAILJMPd64:
case X86::TAILJMPr64_REX:
case X86::TAILJMPm64_REX:
case X86::TAILJMPd64_REX:
// Lower these as normal, but add some comments.
OutStreamer->AddComment("TAILCALL");
break;
case X86::TLS_addr32:
case X86::TLS_addr64:
case X86::TLS_base_addr32:
case X86::TLS_base_addr64:
return LowerTlsAddr(MCInstLowering, *MI);
case X86::MOVPC32r: {
// This is a pseudo op for a two instruction sequence with a label, which
// looks like:
// call "L1$pb"
// "L1$pb":
// popl %esi
// Emit the call.
MCSymbol *PICBase = MF->getPICBaseSymbol();
// FIXME: We would like an efficient form for this, so we don't have to do a
// lot of extra uniquing.
EmitAndCountInstruction(MCInstBuilder(X86::CALLpcrel32)
.addExpr(MCSymbolRefExpr::create(PICBase, OutContext)));
// Emit the label.
OutStreamer->EmitLabel(PICBase);
// popl $reg
EmitAndCountInstruction(MCInstBuilder(X86::POP32r)
.addReg(MI->getOperand(0).getReg()));
return;
}
case X86::ADD32ri: {
// Lower the MO_GOT_ABSOLUTE_ADDRESS form of ADD32ri.
if (MI->getOperand(2).getTargetFlags() != X86II::MO_GOT_ABSOLUTE_ADDRESS)
break;
// Okay, we have something like:
// EAX = ADD32ri EAX, MO_GOT_ABSOLUTE_ADDRESS(@MYGLOBAL)
// For this, we want to print something like:
// MYGLOBAL + (. - PICBASE)
// However, we can't generate a ".", so just emit a new label here and refer
// to it.
MCSymbol *DotSym = OutContext.createTempSymbol();
OutStreamer->EmitLabel(DotSym);
// Now that we have emitted the label, lower the complex operand expression.
MCSymbol *OpSym = MCInstLowering.GetSymbolFromOperand(MI->getOperand(2));
const MCExpr *DotExpr = MCSymbolRefExpr::create(DotSym, OutContext);
const MCExpr *PICBase =
MCSymbolRefExpr::create(MF->getPICBaseSymbol(), OutContext);
DotExpr = MCBinaryExpr::createSub(DotExpr, PICBase, OutContext);
DotExpr = MCBinaryExpr::createAdd(MCSymbolRefExpr::create(OpSym,OutContext),
DotExpr, OutContext);
EmitAndCountInstruction(MCInstBuilder(X86::ADD32ri)
.addReg(MI->getOperand(0).getReg())
.addReg(MI->getOperand(1).getReg())
.addExpr(DotExpr));
return;
}
case TargetOpcode::STATEPOINT:
return LowerSTATEPOINT(*MI, MCInstLowering);
case TargetOpcode::FAULTING_LOAD_OP:
return LowerFAULTING_LOAD_OP(*MI, MCInstLowering);
case TargetOpcode::STACKMAP:
return LowerSTACKMAP(*MI);
case TargetOpcode::PATCHPOINT:
return LowerPATCHPOINT(*MI, MCInstLowering);
case X86::MORESTACK_RET:
EmitAndCountInstruction(MCInstBuilder(getRetOpcode(*Subtarget)));
return;
case X86::MORESTACK_RET_RESTORE_R10:
// Return, then restore R10.
EmitAndCountInstruction(MCInstBuilder(getRetOpcode(*Subtarget)));
EmitAndCountInstruction(MCInstBuilder(X86::MOV64rr)
.addReg(X86::R10)
.addReg(X86::RAX));
return;
case X86::SEH_PushReg:
OutStreamer->EmitWinCFIPushReg(RI->getSEHRegNum(MI->getOperand(0).getImm()));
return;
case X86::SEH_SaveReg:
OutStreamer->EmitWinCFISaveReg(RI->getSEHRegNum(MI->getOperand(0).getImm()),
MI->getOperand(1).getImm());
return;
case X86::SEH_SaveXMM:
OutStreamer->EmitWinCFISaveXMM(RI->getSEHRegNum(MI->getOperand(0).getImm()),
MI->getOperand(1).getImm());
return;
case X86::SEH_StackAlloc:
OutStreamer->EmitWinCFIAllocStack(MI->getOperand(0).getImm());
return;
case X86::SEH_SetFrame:
OutStreamer->EmitWinCFISetFrame(RI->getSEHRegNum(MI->getOperand(0).getImm()),
MI->getOperand(1).getImm());
return;
case X86::SEH_PushFrame:
OutStreamer->EmitWinCFIPushFrame(MI->getOperand(0).getImm());
return;
case X86::SEH_EndPrologue:
OutStreamer->EmitWinCFIEndProlog();
return;
case X86::SEH_Epilogue: {
MachineBasicBlock::const_iterator MBBI(MI);
// Check if preceded by a call and emit nop if so.
for (MBBI = PrevCrossBBInst(MBBI); MBBI; MBBI = PrevCrossBBInst(MBBI)) {
// Conservatively assume that pseudo instructions don't emit code and keep
// looking for a call. We may emit an unnecessary nop in some cases.
if (!MBBI->isPseudo()) {
if (MBBI->isCall())
EmitAndCountInstruction(MCInstBuilder(X86::NOOP));
break;
}
}
return;
}
// Lower PSHUFB and VPERMILP normally but add a comment if we can find
// a constant shuffle mask. We won't be able to do this at the MC layer
// because the mask isn't an immediate.
case X86::PSHUFBrm:
case X86::VPSHUFBrm:
case X86::VPSHUFBYrm: {
if (!OutStreamer->isVerboseAsm())
break;
assert(MI->getNumOperands() > 5 &&
"We should always have at least 5 operands!");
const MachineOperand &DstOp = MI->getOperand(0);
const MachineOperand &SrcOp = MI->getOperand(1);
const MachineOperand &MaskOp = MI->getOperand(5);
if (auto *C = getConstantFromPool(*MI, MaskOp)) {
SmallVector<int, 16> Mask;
DecodePSHUFBMask(C, Mask);
if (!Mask.empty())
OutStreamer->AddComment(getShuffleComment(DstOp, SrcOp, Mask));
}
break;
}
case X86::VPERMILPSrm:
case X86::VPERMILPDrm:
case X86::VPERMILPSYrm:
case X86::VPERMILPDYrm: {
if (!OutStreamer->isVerboseAsm())
break;
assert(MI->getNumOperands() > 5 &&
"We should always have at least 5 operands!");
const MachineOperand &DstOp = MI->getOperand(0);
const MachineOperand &SrcOp = MI->getOperand(1);
const MachineOperand &MaskOp = MI->getOperand(5);
if (auto *C = getConstantFromPool(*MI, MaskOp)) {
SmallVector<int, 16> Mask;
DecodeVPERMILPMask(C, Mask);
if (!Mask.empty())
OutStreamer->AddComment(getShuffleComment(DstOp, SrcOp, Mask));
}
break;
}
// For loads from a constant pool to a vector register, print the constant
// loaded.
case X86::MOVAPDrm:
case X86::VMOVAPDrm:
case X86::VMOVAPDYrm:
case X86::MOVUPDrm:
case X86::VMOVUPDrm:
case X86::VMOVUPDYrm:
case X86::MOVAPSrm:
case X86::VMOVAPSrm:
case X86::VMOVAPSYrm:
case X86::MOVUPSrm:
case X86::VMOVUPSrm:
case X86::VMOVUPSYrm:
case X86::MOVDQArm:
case X86::VMOVDQArm:
case X86::VMOVDQAYrm:
case X86::MOVDQUrm:
case X86::VMOVDQUrm:
case X86::VMOVDQUYrm:
if (!OutStreamer->isVerboseAsm())
break;
if (MI->getNumOperands() > 4)
if (auto *C = getConstantFromPool(*MI, MI->getOperand(4))) {
std::string Comment;
raw_string_ostream CS(Comment);
const MachineOperand &DstOp = MI->getOperand(0);
CS << X86ATTInstPrinter::getRegisterName(DstOp.getReg()) << " = ";
if (auto *CDS = dyn_cast<ConstantDataSequential>(C)) {
CS << "[";
for (int i = 0, NumElements = CDS->getNumElements(); i < NumElements; ++i) {
if (i != 0)
CS << ",";
if (CDS->getElementType()->isIntegerTy())
CS << CDS->getElementAsInteger(i);
else if (CDS->getElementType()->isFloatTy())
CS << CDS->getElementAsFloat(i);
else if (CDS->getElementType()->isDoubleTy())
CS << CDS->getElementAsDouble(i);
else
CS << "?";
}
CS << "]";
OutStreamer->AddComment(CS.str());
} else if (auto *CV = dyn_cast<ConstantVector>(C)) {
CS << "<";
for (int i = 0, NumOperands = CV->getNumOperands(); i < NumOperands; ++i) {
if (i != 0)
CS << ",";
Constant *COp = CV->getOperand(i);
if (isa<UndefValue>(COp)) {
CS << "u";
} else if (auto *CI = dyn_cast<ConstantInt>(COp)) {
CS << CI->getZExtValue();
} else if (auto *CF = dyn_cast<ConstantFP>(COp)) {
SmallString<32> Str;
CF->getValueAPF().toString(Str);
CS << Str;
} else {
CS << "?";
}
}
CS << ">";
OutStreamer->AddComment(CS.str());
}
}
break;
}
MCInst TmpInst;
MCInstLowering.Lower(MI, TmpInst);
// Stackmap shadows cannot include branch targets, so we can count the bytes
// in a call towards the shadow, but must ensure that the no thread returns
// in to the stackmap shadow. The only way to achieve this is if the call
// is at the end of the shadow.
if (MI->isCall()) {
// Count then size of the call towards the shadow
SMShadowTracker.count(TmpInst, getSubtargetInfo());
// Then flush the shadow so that we fill with nops before the call, not
// after it.
SMShadowTracker.emitShadowPadding(*OutStreamer, getSubtargetInfo());
// Then emit the call
OutStreamer->EmitInstruction(TmpInst, getSubtargetInfo());
return;
}
EmitAndCountInstruction(TmpInst);
}