llvm::MCExpr Class Reference

Base class for the full range of assembler expressions which are needed for parsing. More...

#include "llvm/MC/MCExpr.h"

Inheritance diagram for llvm::MCExpr:

Public Types
enum	ExprKind : uint8_t {   Binary , Constant , SymbolRef , Unary ,   Target }

Public Member Functions
	MCExpr (const MCExpr &)=delete
MCExpr &	operator= (const MCExpr &)=delete
Accessors
ExprKind	getKind () const
SMLoc	getLoc () const
Utility Methods
void	print (raw_ostream &OS, const MCAsmInfo *MAI, bool InParens=false) const
void	dump () const
bool	isSymbolUsedInExpression (const MCSymbol *Sym) const
	Returns whether the given symbol is used anywhere in the expression or subexpressions.
Expression Evaluation
bool	evaluateAsAbsolute (int64_t &Res, const MCAssembler &Asm, const SectionAddrMap &Addrs) const
	Try to evaluate the expression to an absolute value.
bool	evaluateAsAbsolute (int64_t &Res) const
bool	evaluateAsAbsolute (int64_t &Res, const MCAssembler &Asm) const
bool	evaluateAsAbsolute (int64_t &Res, const MCAssembler *Asm) const
bool	evaluateKnownAbsolute (int64_t &Res, const MCAssembler &Asm) const
	Aggressive variant of evaluateAsRelocatable when relocations are unavailable (e.g.
bool	evaluateAsRelocatable (MCValue &Res, const MCAssembler *Asm, const MCFixup *Fixup) const
	Try to evaluate the expression to a relocatable value, i.e.
bool	evaluateAsValue (MCValue &Res, const MCAssembler &Asm) const
	Try to evaluate the expression to the form (a - b + constant) where neither a nor b are variables.
MCFragment *	findAssociatedFragment () const
	Find the "associated section" for this expression, which is currently defined as the absolute section for constants, or otherwise the section associated with the first defined symbol in the expression.

Protected Member Functions
	MCExpr (ExprKind Kind, SMLoc Loc, unsigned SubclassData=0)
bool	evaluateAsRelocatableImpl (MCValue &Res, const MCAssembler *Asm, const MCFixup *Fixup, const SectionAddrMap *Addrs, bool InSet) const
unsigned	getSubclassData () const

Detailed Description

Base class for the full range of assembler expressions which are needed for parsing.

Definition at line 34 of file MCExpr.h.

Member Enumeration Documentation

ExprKind

enum llvm::MCExpr::ExprKind : uint8_t

Enumerator
Binary	Binary expressions.
Constant	Constant expressions.
SymbolRef	References to labels and assigned expressions.
Unary	Unary expressions.
Target	Target specific expression.

Definition at line 36 of file MCExpr.h.

Constructor & Destructor Documentation

MCExpr() [1/2]

llvm::MCExpr::MCExpr ( ExprKind  Kind, SMLoc  Loc, unsigned  SubclassData = 0  )

inlineexplicitprotected

Definition at line 59 of file MCExpr.h.

References assert().

MCExpr() [2/2]

llvm::MCExpr::MCExpr ( const MCExpr &  )

delete

Member Function Documentation

dump()

LLVM_DUMP_METHOD void MCExpr::dump

(

)

const

Definition at line 174 of file MCExpr.cpp.

References llvm::dbgs().

evaluateAsAbsolute() [1/4]

bool MCExpr::evaluateAsAbsolute

(

int64_t &

Res

)

const

Definition at line 577 of file MCExpr.cpp.

evaluateAsAbsolute() [2/4]

bool MCExpr::evaluateAsAbsolute	(	int64_t &	Res,
		const MCAssembler &	Asm
	)		const

Definition at line 588 of file MCExpr.cpp.

evaluateAsAbsolute() [3/4]

bool MCExpr::evaluateAsAbsolute	(	int64_t &	Res,
		const MCAssembler &	Asm,
		const SectionAddrMap &	Addrs
	)		const

Try to evaluate the expression to an absolute value.

Parameters

Res	- The absolute value, if evaluation succeeds.

Returns

- True on success.

Definition at line 581 of file MCExpr.cpp.

Referenced by targetOpKnownBitsMapHelper().

evaluateAsAbsolute() [4/4]

bool MCExpr::evaluateAsAbsolute	(	int64_t &	Res,
		const MCAssembler *	Asm
	)		const

Definition at line 592 of file MCExpr.cpp.

evaluateAsRelocatable()

bool MCExpr::evaluateAsRelocatable	(	MCValue &	Res,
		const MCAssembler *	Asm,
		const MCFixup *	Fixup
	)		const

Try to evaluate the expression to a relocatable value, i.e.

an expression of the fixed form (a - b + constant).

Parameters

Res	- The relocatable value, if evaluation succeeds.
Asm	- The assembler object to use for evaluating values.
Fixup	- The Fixup object if available.

Returns

- True on success.

Definition at line 819 of file MCExpr.cpp.

References evaluateAsRelocatableImpl(), and Fixup.

Referenced by llvm::DelayedMCExprs::assignDocNode(), llvm::PPCMCExpr::evaluateAsConstant(), llvm::RISCVMCExpr::evaluateAsConstant(), llvm::AVRMCExpr::evaluateAsConstant(), llvm::AArch64MCExpr::evaluateAsRelocatableImpl(), llvm::AArch64AuthMCExpr::evaluateAsRelocatableImpl(), llvm::AMDGPUMCExpr::evaluateAsRelocatableImpl(), llvm::AVRMCExpr::evaluateAsRelocatableImpl(), llvm::CSKYMCExpr::evaluateAsRelocatableImpl(), llvm::HexagonMCExpr::evaluateAsRelocatableImpl(), llvm::LanaiMCExpr::evaluateAsRelocatableImpl(), llvm::LoongArchMCExpr::evaluateAsRelocatableImpl(), llvm::MipsMCExpr::evaluateAsRelocatableImpl(), llvm::PPCMCExpr::evaluateAsRelocatableImpl(), llvm::RISCVMCExpr::evaluateAsRelocatableImpl(), llvm::SparcMCExpr::evaluateAsRelocatableImpl(), llvm::SystemZMCExpr::evaluateAsRelocatableImpl(), llvm::VEMCExpr::evaluateAsRelocatableImpl(), llvm::XtensaMCExpr::evaluateAsRelocatableImpl(), llvm::RISCVAsmBackend::evaluateTargetFixup(), getOffsetAndDataFragment(), llvm::RISCVMCExpr::getPCRelHiFixup(), llvm::MachObjectWriter::getSymbolAddress(), and llvm::MCAssembler::isThumbFunc().

evaluateAsRelocatableImpl()

bool MCExpr::evaluateAsRelocatableImpl ( MCValue &  Res, const MCAssembler *  Asm, const MCFixup *  Fixup, const SectionAddrMap *  Addrs, bool  InSet  ) const

protected

-(a - b + const) ==> (b - a - const)

Definition at line 844 of file MCExpr.cpp.

References A, llvm::MCBinaryExpr::Add, llvm::MCBinaryExpr::And, llvm::MCBinaryExpr::AShr, B, Binary, canExpand(), Constant, llvm::MCSymbolRefExpr::create(), llvm::MCBinaryExpr::Div, llvm::MCBinaryExpr::EQ, evaluateAsRelocatableImpl(), evaluateSymbolicAdd(), Fixup, llvm::MCValue::get(), llvm::MCValue::getConstant(), getKind(), llvm::MCSymbolRefExpr::getKind(), llvm::MCBinaryExpr::getLHS(), llvm::MCUnaryExpr::getOpcode(), llvm::MCBinaryExpr::getOpcode(), llvm::MCValue::getRefKind(), llvm::MCBinaryExpr::getRHS(), llvm::MCUnaryExpr::getSubExpr(), llvm::MCValue::getSymA(), llvm::MCValue::getSymB(), llvm::MCSymbolRefExpr::getSymbol(), llvm::MCBinaryExpr::GT, llvm::MCBinaryExpr::GTE, llvm::MCSymbolRefExpr::hasSubsectionsViaSymbols(), llvm::MCValue::isAbsolute(), llvm::MCBinaryExpr::LAnd, LHS, llvm_unreachable, llvm::MCUnaryExpr::LNot, llvm::MCBinaryExpr::LOr, llvm::MCBinaryExpr::LShr, llvm::MCBinaryExpr::LT, llvm::MCBinaryExpr::LTE, llvm::MCUnaryExpr::Minus, llvm::MCBinaryExpr::Mod, llvm::MCBinaryExpr::Mul, llvm::MCBinaryExpr::NE, llvm::MCUnaryExpr::Not, llvm::MCBinaryExpr::Or, llvm::MCBinaryExpr::OrNot, llvm::MCUnaryExpr::Plus, RHS, llvm::MCBinaryExpr::Shl, llvm::MCBinaryExpr::Sub, Sym, SymbolRef, Target, Unary, llvm::MCSymbolRefExpr::VK_None, and llvm::MCBinaryExpr::Xor.

Referenced by evaluateAsRelocatable(), evaluateAsRelocatableImpl(), and evaluateAsValue().

evaluateAsValue()

bool MCExpr::evaluateAsValue	(	MCValue &	Res,
		const MCAssembler &	Asm
	)		const

Try to evaluate the expression to the form (a - b + constant) where neither a nor b are variables.

This is a more aggressive variant of evaluateAsRelocatable. The intended use is for when relocations are not available, like the .size directive.

Definition at line 824 of file MCExpr.cpp.

References evaluateAsRelocatableImpl().

Referenced by llvm::MCAssembler::computeFragmentSize(), llvm::MCAssembler::getBaseSymbol(), and getSymbolOffsetImpl().

evaluateKnownAbsolute()

bool MCExpr::evaluateKnownAbsolute	(	int64_t &	Res,
		const MCAssembler &	Asm
	)		const

Aggressive variant of evaluateAsRelocatable when relocations are unavailable (e.g.

.fill). Expects callers to handle errors when true is returned.

Definition at line 596 of file MCExpr.cpp.

Referenced by computeLabelDiff(), llvm::LoongArchAsmBackend::relaxDwarfCFA(), llvm::RISCVAsmBackend::relaxDwarfCFA(), llvm::LoongArchAsmBackend::relaxDwarfLineAddr(), llvm::RISCVAsmBackend::relaxDwarfLineAddr(), llvm::LoongArchAsmBackend::relaxLEB128(), and llvm::RISCVAsmBackend::relaxLEB128().

findAssociatedFragment()

MCFragment * MCExpr::findAssociatedFragment

(

)

const

Find the "associated section" for this expression, which is currently defined as the absolute section for constants, or otherwise the section associated with the first defined symbol in the expression.

Definition at line 1060 of file MCExpr.cpp.

References llvm::MCSymbol::AbsolutePseudoFragment, Binary, Constant, findAssociatedFragment(), getKind(), llvm::MCBinaryExpr::getLHS(), llvm::MCBinaryExpr::getOpcode(), llvm::MCBinaryExpr::getRHS(), llvm::MCSymbolRefExpr::getSymbol(), llvm_unreachable, llvm::MCBinaryExpr::Sub, Sym, SymbolRef, Target, and Unary.

Referenced by findAssociatedFragment(), llvm::AMDGPUMCExpr::findAssociatedFragment(), llvm::ARMMCExpr::findAssociatedFragment(), llvm::AVRMCExpr::findAssociatedFragment(), llvm::CSKYMCExpr::findAssociatedFragment(), llvm::HexagonMCExpr::findAssociatedFragment(), llvm::LanaiMCExpr::findAssociatedFragment(), llvm::LoongArchMCExpr::findAssociatedFragment(), llvm::MipsMCExpr::findAssociatedFragment(), llvm::PPCMCExpr::findAssociatedFragment(), llvm::RISCVMCExpr::findAssociatedFragment(), llvm::SparcMCExpr::findAssociatedFragment(), llvm::SystemZMCExpr::findAssociatedFragment(), llvm::VEMCExpr::findAssociatedFragment(), llvm::XtensaMCExpr::findAssociatedFragment(), and llvm::MCSymbol::getFragment().

getKind()

ExprKind llvm::MCExpr::getKind ( ) const

inline

Definition at line 78 of file MCExpr.h.

Referenced by evaluateAsRelocatableImpl(), EvaluateCRExpr(), findAssociatedFragment(), fixELFSymbolsInTLSFixupsImpl(), getAccessVariant(), llvm::CSKYMCCodeEmitter::getBareSymbolOpValue(), llvm::CSKYMCCodeEmitter::getBranchSymbolOpValue(), llvm::CSKYMCCodeEmitter::getCallSymbolOpValue(), llvm::CSKYMCCodeEmitter::getConstpoolSymbolOpValue(), llvm::CSKYMCCodeEmitter::getDataSymbolOpValue(), llvm::PPCMCCodeEmitter::getDispRI34PCRelEncoding(), llvm::MipsMCCodeEmitter::getExprOpValue(), hasGOTReference(), hasSecRelSymbolRef(), hasVariantSymbol(), llvm::MCOperand::isBareSymbolRef(), isEvaluated(), isSymbolUsedInExpression(), knownBitsMapHelper(), needsExpandMemInst(), needsPCRel(), llvm::X86Operand::print(), print(), llvm::ARMMCExpr::printImpl(), llvm::ARMInstPrinter::printOperand(), startsWithGlobalOffsetTable(), tryFoldHelper(), and llvm::MCStreamer::visitUsedExpr().

getLoc()

SMLoc llvm::MCExpr::getLoc ( ) const

inline

Definition at line 79 of file MCExpr.h.

Referenced by llvm::MCAssembler::getBaseSymbol(), llvm::MipsMCCodeEmitter::getExprOpValue(), llvm::LoongArchAsmBackend::relaxLEB128(), llvm::RISCVAsmBackend::relaxLEB128(), llvm::MCStreamer::switchSection(), and tryFoldHelper().

getSubclassData()

unsigned llvm::MCExpr::getSubclassData ( ) const

inlineprotected

Definition at line 69 of file MCExpr.h.

Referenced by llvm::MCSymbolRefExpr::getKind(), llvm::MCUnaryExpr::getOpcode(), llvm::MCBinaryExpr::getOpcode(), llvm::MCConstantExpr::getSizeInBytes(), llvm::MCSymbolRefExpr::hasSubsectionsViaSymbols(), and llvm::MCConstantExpr::useHexFormat().

isSymbolUsedInExpression()

bool MCExpr::isSymbolUsedInExpression

(

const MCSymbol *

Sym

)

const

Returns whether the given symbol is used anywhere in the expression or subexpressions.

Definition at line 180 of file MCExpr.cpp.

References Binary, Constant, getKind(), llvm::MCBinaryExpr::getLHS(), llvm::MCBinaryExpr::getRHS(), llvm::MCSymbol::getVariableValue(), isSymbolUsedInExpression(), llvm::MCSymbol::isVariable(), llvm::MCSymbol::isWeakExternal(), llvm_unreachable, Sym, SymbolRef, Target, and Unary.

Referenced by llvm::MCResourceInfo::gatherResourceInfo(), and isSymbolUsedInExpression().

operator=()

MCExpr & llvm::MCExpr::operator= ( const MCExpr &  )

delete

print()

void MCExpr::print	(	raw_ostream &	OS,
		const MCAsmInfo *	MAI,
		bool	InParens = false
	)		const

Definition at line 40 of file MCExpr.cpp.

References llvm::MCBinaryExpr::Add, llvm::MCBinaryExpr::And, llvm::MCBinaryExpr::AShr, Binary, Constant, llvm::MCBinaryExpr::Div, llvm::MCBinaryExpr::EQ, llvm::format(), getKind(), llvm::MCSymbolRefExpr::getKind(), llvm::MCBinaryExpr::getLHS(), llvm::MCUnaryExpr::getOpcode(), llvm::MCBinaryExpr::getOpcode(), llvm::MCBinaryExpr::getRHS(), llvm::MCUnaryExpr::getSubExpr(), llvm::MCSymbolRefExpr::getSymbol(), llvm::MCSymbolRefExpr::getVariantKindName(), llvm::MCBinaryExpr::GT, llvm::MCBinaryExpr::GTE, llvm::MCBinaryExpr::LAnd, llvm_unreachable, llvm::MCUnaryExpr::LNot, llvm::MCBinaryExpr::LOr, llvm::MCBinaryExpr::LShr, llvm::MCBinaryExpr::LT, llvm::MCBinaryExpr::LTE, llvm::MCUnaryExpr::Minus, llvm::MCBinaryExpr::Mod, llvm::MCBinaryExpr::Mul, llvm::MCBinaryExpr::NE, llvm::MCUnaryExpr::Not, llvm::MCBinaryExpr::Or, llvm::MCBinaryExpr::OrNot, OS, llvm::MCUnaryExpr::Plus, print(), llvm::MCBinaryExpr::Shl, llvm::MCBinaryExpr::Sub, Sym, SymbolRef, Target, Unary, llvm::MCAsmInfo::useParensForDollarSignNames(), llvm::MCAsmInfo::useParensForSymbolVariant(), llvm::Twine::utohexstr(), llvm::MCSymbolRefExpr::VK_None, and llvm::MCBinaryExpr::Xor.

Referenced by print(), llvm::AArch64InstPrinter::printAddSubImm(), llvm::ARMInstPrinter::printAdrLabelOperand(), llvm::AMDGPU::printAMDGPUMCExpr(), llvm::AArch64InstPrinter::printAMIndexedWB(), llvm::CSKYInstPrinter::printConstpool(), llvm::CSKYInstPrinter::printDataSymbol(), llvm::AArch64MCExpr::printImpl(), llvm::AArch64AuthMCExpr::printImpl(), llvm::ARMMCExpr::printImpl(), llvm::AVRMCExpr::printImpl(), llvm::CSKYMCExpr::printImpl(), llvm::HexagonMCExpr::printImpl(), llvm::LanaiMCExpr::printImpl(), llvm::LoongArchMCExpr::printImpl(), llvm::MipsMCExpr::printImpl(), llvm::NVPTXGenericMCSymbolRefExpr::printImpl(), llvm::PPCMCExpr::printImpl(), llvm::RISCVMCExpr::printImpl(), llvm::SparcMCExpr::printImpl(), llvm::SystemZMCExpr::printImpl(), llvm::VEMCExpr::printImpl(), llvm::XtensaMCExpr::printImpl(), llvm::X86IntelInstPrinter::printMemOffset(), llvm::X86ATTInstPrinter::printMemOffset(), printMemoryImmediateOffset(), llvm::X86IntelInstPrinter::printMemReference(), llvm::X86ATTInstPrinter::printMemReference(), llvm::SparcInstPrinter::printOperand(), llvm::VEInstPrinter::printOperand(), llvm::ARMInstPrinter::printOperand(), llvm::CSKYInstPrinter::printOperand(), llvm::RISCVInstPrinter::printOperand(), printOperand(), llvm::SystemZInstPrinterCommon::printOperand(), llvm::SystemZInstPrinterCommon::printPCRelOperand(), llvm::ARMInstPrinter::printThumbLdrLabelOperand(), llvm::PPCInstPrinter::printTLSCall(), and llvm::AArch64InstPrinter::printUImm12Offset().

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The documentation for this class was generated from the following files:

• include/llvm/MC/MCExpr.h
• lib/MC/MCExpr.cpp