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llvm-mirror/include/llvm/MC/MCExpr.h
Victor Huang de9b762793 [AIX][TLS] Add ASM portion changes to support TLSGD relocations to XCOFF objects 
- Add new variantKinds for the symbol's variable offset and region handle
- Print the proper relocation specifier @gd in the asm streamer when emitting
  the TC Entry for the variable offset for the symbol
- Fix the switch section failure between the TC Entry of variable offset and
  region handle
- Put .__tls_get_addr symbol in the ProgramCodeSects with XTY_ER property

Reviewed by: sfertile

Differential Revision: https://reviews.llvm.org/D100956
2021-04-29 13:18:59 -05:00

673 lines
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//===- MCExpr.h - Assembly Level Expressions --------------------*- C++ -*-===//
//
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
// See https://llvm.org/LICENSE.txt for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
//
//===----------------------------------------------------------------------===//
#ifndef LLVM_MC_MCEXPR_H
#define LLVM_MC_MCEXPR_H
#include "llvm/ADT/DenseMap.h"
#include "llvm/Support/SMLoc.h"
#include <cstdint>
namespace llvm {
class MCAsmInfo;
class MCAsmLayout;
class MCAssembler;
class MCContext;
class MCFixup;
class MCFragment;
class MCSection;
class MCStreamer;
class MCSymbol;
class MCValue;
class raw_ostream;
class StringRef;
using SectionAddrMap = DenseMap<const MCSection *, uint64_t>;
/// Base class for the full range of assembler expressions which are
/// needed for parsing.
class MCExpr {
public:
enum ExprKind : uint8_t {
Binary, ///< Binary expressions.
Constant, ///< Constant expressions.
SymbolRef, ///< References to labels and assigned expressions.
Unary, ///< Unary expressions.
Target ///< Target specific expression.
};
private:
static const unsigned NumSubclassDataBits = 24;
static_assert(
NumSubclassDataBits == CHAR_BIT * (sizeof(unsigned) - sizeof(ExprKind)),
"ExprKind and SubclassData together should take up one word");
ExprKind Kind;
/// Field reserved for use by MCExpr subclasses.
unsigned SubclassData : NumSubclassDataBits;
SMLoc Loc;
bool evaluateAsAbsolute(int64_t &Res, const MCAssembler *Asm,
const MCAsmLayout *Layout,
const SectionAddrMap *Addrs, bool InSet) const;
protected:
explicit MCExpr(ExprKind Kind, SMLoc Loc, unsigned SubclassData = 0)
: Kind(Kind), SubclassData(SubclassData), Loc(Loc) {
assert(SubclassData < (1 << NumSubclassDataBits) &&
"Subclass data too large");
}
bool evaluateAsRelocatableImpl(MCValue &Res, const MCAssembler *Asm,
const MCAsmLayout *Layout,
const MCFixup *Fixup,
const SectionAddrMap *Addrs, bool InSet) const;
unsigned getSubclassData() const { return SubclassData; }
public:
MCExpr(const MCExpr &) = delete;
MCExpr &operator=(const MCExpr &) = delete;
/// \name Accessors
/// @{
ExprKind getKind() const { return Kind; }
SMLoc getLoc() const { return Loc; }
/// @}
/// \name Utility Methods
/// @{
void print(raw_ostream &OS, const MCAsmInfo *MAI,
bool InParens = false) const;
void dump() const;
/// @}
/// \name Expression Evaluation
/// @{
/// Try to evaluate the expression to an absolute value.
///
/// \param Res - The absolute value, if evaluation succeeds.
/// \param Layout - The assembler layout object to use for evaluating symbol
/// values. If not given, then only non-symbolic expressions will be
/// evaluated.
/// \return - True on success.
bool evaluateAsAbsolute(int64_t &Res, const MCAsmLayout &Layout,
const SectionAddrMap &Addrs) const;
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 evaluateAsAbsolute(int64_t &Res, const MCAsmLayout &Layout) const;
bool evaluateKnownAbsolute(int64_t &Res, const MCAsmLayout &Layout) const;
/// Try to evaluate the expression to a relocatable value, i.e. an
/// expression of the fixed form (a - b + constant).
///
/// \param Res - The relocatable value, if evaluation succeeds.
/// \param Layout - The assembler layout object to use for evaluating values.
/// \param Fixup - The Fixup object if available.
/// \return - True on success.
bool evaluateAsRelocatable(MCValue &Res, const MCAsmLayout *Layout,
const MCFixup *Fixup) 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.
bool evaluateAsValue(MCValue &Res, const MCAsmLayout &Layout) 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.
MCFragment *findAssociatedFragment() const;
/// @}
};
inline raw_ostream &operator<<(raw_ostream &OS, const MCExpr &E) {
E.print(OS, nullptr);
return OS;
}
//// Represent a constant integer expression.
class MCConstantExpr : public MCExpr {
int64_t Value;
// Subclass data stores SizeInBytes in bits 0..7 and PrintInHex in bit 8.
static const unsigned SizeInBytesBits = 8;
static const unsigned SizeInBytesMask = (1 << SizeInBytesBits) - 1;
static const unsigned PrintInHexBit = 1 << SizeInBytesBits;
static unsigned encodeSubclassData(bool PrintInHex, unsigned SizeInBytes) {
assert(SizeInBytes <= sizeof(int64_t) && "Excessive size");
return SizeInBytes | (PrintInHex ? PrintInHexBit : 0);
}
MCConstantExpr(int64_t Value, bool PrintInHex, unsigned SizeInBytes)
: MCExpr(MCExpr::Constant, SMLoc(),
encodeSubclassData(PrintInHex, SizeInBytes)), Value(Value) {}
public:
/// \name Construction
/// @{
static const MCConstantExpr *create(int64_t Value, MCContext &Ctx,
bool PrintInHex = false,
unsigned SizeInBytes = 0);
/// @}
/// \name Accessors
/// @{
int64_t getValue() const { return Value; }
unsigned getSizeInBytes() const {
return getSubclassData() & SizeInBytesMask;
}
bool useHexFormat() const { return (getSubclassData() & PrintInHexBit) != 0; }
/// @}
static bool classof(const MCExpr *E) {
return E->getKind() == MCExpr::Constant;
}
};
/// Represent a reference to a symbol from inside an expression.
///
/// A symbol reference in an expression may be a use of a label, a use of an
/// assembler variable (defined constant), or constitute an implicit definition
/// of the symbol as external.
class MCSymbolRefExpr : public MCExpr {
public:
enum VariantKind : uint16_t {
VK_None,
VK_Invalid,
VK_GOT,
VK_GOTOFF,
VK_GOTREL,
VK_PCREL,
VK_GOTPCREL,
VK_GOTTPOFF,
VK_INDNTPOFF,
VK_NTPOFF,
VK_GOTNTPOFF,
VK_PLT,
VK_TLSGD,
VK_TLSLD,
VK_TLSLDM,
VK_TPOFF,
VK_DTPOFF,
VK_TLSCALL, // symbol(tlscall)
VK_TLSDESC, // symbol(tlsdesc)
VK_TLVP, // Mach-O thread local variable relocations
VK_TLVPPAGE,
VK_TLVPPAGEOFF,
VK_PAGE,
VK_PAGEOFF,
VK_GOTPAGE,
VK_GOTPAGEOFF,
VK_SECREL,
VK_SIZE, // symbol@SIZE
VK_WEAKREF, // The link between the symbols in .weakref foo, bar
VK_X86_ABS8,
VK_X86_PLTOFF,
VK_ARM_NONE,
VK_ARM_GOT_PREL,
VK_ARM_TARGET1,
VK_ARM_TARGET2,
VK_ARM_PREL31,
VK_ARM_SBREL, // symbol(sbrel)
VK_ARM_TLSLDO, // symbol(tlsldo)
VK_ARM_TLSDESCSEQ,
VK_AVR_NONE,
VK_AVR_LO8,
VK_AVR_HI8,
VK_AVR_HLO8,
VK_AVR_DIFF8,
VK_AVR_DIFF16,
VK_AVR_DIFF32,
VK_AVR_PM,
VK_PPC_LO, // symbol@l
VK_PPC_HI, // symbol@h
VK_PPC_HA, // symbol@ha
VK_PPC_HIGH, // symbol@high
VK_PPC_HIGHA, // symbol@higha
VK_PPC_HIGHER, // symbol@higher
VK_PPC_HIGHERA, // symbol@highera
VK_PPC_HIGHEST, // symbol@highest
VK_PPC_HIGHESTA, // symbol@highesta
VK_PPC_GOT_LO, // symbol@got@l
VK_PPC_GOT_HI, // symbol@got@h
VK_PPC_GOT_HA, // symbol@got@ha
VK_PPC_TOCBASE, // symbol@tocbase
VK_PPC_TOC, // symbol@toc
VK_PPC_TOC_LO, // symbol@toc@l
VK_PPC_TOC_HI, // symbol@toc@h
VK_PPC_TOC_HA, // symbol@toc@ha
VK_PPC_U, // symbol@u
VK_PPC_L, // symbol@l
VK_PPC_DTPMOD, // symbol@dtpmod
VK_PPC_TPREL_LO, // symbol@tprel@l
VK_PPC_TPREL_HI, // symbol@tprel@h
VK_PPC_TPREL_HA, // symbol@tprel@ha
VK_PPC_TPREL_HIGH, // symbol@tprel@high
VK_PPC_TPREL_HIGHA, // symbol@tprel@higha
VK_PPC_TPREL_HIGHER, // symbol@tprel@higher
VK_PPC_TPREL_HIGHERA, // symbol@tprel@highera
VK_PPC_TPREL_HIGHEST, // symbol@tprel@highest
VK_PPC_TPREL_HIGHESTA, // symbol@tprel@highesta
VK_PPC_DTPREL_LO, // symbol@dtprel@l
VK_PPC_DTPREL_HI, // symbol@dtprel@h
VK_PPC_DTPREL_HA, // symbol@dtprel@ha
VK_PPC_DTPREL_HIGH, // symbol@dtprel@high
VK_PPC_DTPREL_HIGHA, // symbol@dtprel@higha
VK_PPC_DTPREL_HIGHER, // symbol@dtprel@higher
VK_PPC_DTPREL_HIGHERA, // symbol@dtprel@highera
VK_PPC_DTPREL_HIGHEST, // symbol@dtprel@highest
VK_PPC_DTPREL_HIGHESTA, // symbol@dtprel@highesta
VK_PPC_GOT_TPREL, // symbol@got@tprel
VK_PPC_GOT_TPREL_LO, // symbol@got@tprel@l
VK_PPC_GOT_TPREL_HI, // symbol@got@tprel@h
VK_PPC_GOT_TPREL_HA, // symbol@got@tprel@ha
VK_PPC_GOT_DTPREL, // symbol@got@dtprel
VK_PPC_GOT_DTPREL_LO, // symbol@got@dtprel@l
VK_PPC_GOT_DTPREL_HI, // symbol@got@dtprel@h
VK_PPC_GOT_DTPREL_HA, // symbol@got@dtprel@ha
VK_PPC_TLS, // symbol@tls
VK_PPC_GOT_TLSGD, // symbol@got@tlsgd
VK_PPC_GOT_TLSGD_LO, // symbol@got@tlsgd@l
VK_PPC_GOT_TLSGD_HI, // symbol@got@tlsgd@h
VK_PPC_GOT_TLSGD_HA, // symbol@got@tlsgd@ha
VK_PPC_TLSGD, // symbol@tlsgd
VK_PPC_AIX_TLSGD, // symbol@gd
VK_PPC_AIX_TLSGDM, // symbol@m
VK_PPC_GOT_TLSLD, // symbol@got@tlsld
VK_PPC_GOT_TLSLD_LO, // symbol@got@tlsld@l
VK_PPC_GOT_TLSLD_HI, // symbol@got@tlsld@h
VK_PPC_GOT_TLSLD_HA, // symbol@got@tlsld@ha
VK_PPC_GOT_PCREL, // symbol@got@pcrel
VK_PPC_GOT_TLSGD_PCREL, // symbol@got@tlsgd@pcrel
VK_PPC_GOT_TLSLD_PCREL, // symbol@got@tlsld@pcrel
VK_PPC_GOT_TPREL_PCREL, // symbol@got@tprel@pcrel
VK_PPC_TLS_PCREL, // symbol@tls@pcrel
VK_PPC_TLSLD, // symbol@tlsld
VK_PPC_LOCAL, // symbol@local
VK_PPC_NOTOC, // symbol@notoc
VK_PPC_PCREL_OPT, // .reloc expr, R_PPC64_PCREL_OPT, expr
VK_COFF_IMGREL32, // symbol@imgrel (image-relative)
VK_Hexagon_LO16,
VK_Hexagon_HI16,
VK_Hexagon_GPREL,
VK_Hexagon_GD_GOT,
VK_Hexagon_LD_GOT,
VK_Hexagon_GD_PLT,
VK_Hexagon_LD_PLT,
VK_Hexagon_IE,
VK_Hexagon_IE_GOT,
VK_WASM_TYPEINDEX, // Reference to a symbol's type (signature)
VK_WASM_TLSREL, // Memory address relative to __tls_base
VK_WASM_MBREL, // Memory address relative to __memory_base
VK_WASM_TBREL, // Table index relative to __table_base
VK_AMDGPU_GOTPCREL32_LO, // symbol@gotpcrel32@lo
VK_AMDGPU_GOTPCREL32_HI, // symbol@gotpcrel32@hi
VK_AMDGPU_REL32_LO, // symbol@rel32@lo
VK_AMDGPU_REL32_HI, // symbol@rel32@hi
VK_AMDGPU_REL64, // symbol@rel64
VK_AMDGPU_ABS32_LO, // symbol@abs32@lo
VK_AMDGPU_ABS32_HI, // symbol@abs32@hi
VK_VE_HI32, // symbol@hi
VK_VE_LO32, // symbol@lo
VK_VE_PC_HI32, // symbol@pc_hi
VK_VE_PC_LO32, // symbol@pc_lo
VK_VE_GOT_HI32, // symbol@got_hi
VK_VE_GOT_LO32, // symbol@got_lo
VK_VE_GOTOFF_HI32, // symbol@gotoff_hi
VK_VE_GOTOFF_LO32, // symbol@gotoff_lo
VK_VE_PLT_HI32, // symbol@plt_hi
VK_VE_PLT_LO32, // symbol@plt_lo
VK_VE_TLS_GD_HI32, // symbol@tls_gd_hi
VK_VE_TLS_GD_LO32, // symbol@tls_gd_lo
VK_VE_TPOFF_HI32, // symbol@tpoff_hi
VK_VE_TPOFF_LO32, // symbol@tpoff_lo
VK_TPREL,
VK_DTPREL
};
private:
/// The symbol being referenced.
const MCSymbol *Symbol;
// Subclass data stores VariantKind in bits 0..15 and HasSubsectionsViaSymbols
// in bit 16.
static const unsigned VariantKindBits = 16;
static const unsigned VariantKindMask = (1 << VariantKindBits) - 1;
// FIXME: Remove this bit.
static const unsigned HasSubsectionsViaSymbolsBit = 1 << VariantKindBits;
static unsigned encodeSubclassData(VariantKind Kind,
bool HasSubsectionsViaSymbols) {
return (unsigned)Kind |
(HasSubsectionsViaSymbols ? HasSubsectionsViaSymbolsBit : 0);
}
explicit MCSymbolRefExpr(const MCSymbol *Symbol, VariantKind Kind,
const MCAsmInfo *MAI, SMLoc Loc = SMLoc());
public:
/// \name Construction
/// @{
static const MCSymbolRefExpr *create(const MCSymbol *Symbol, MCContext &Ctx) {
return MCSymbolRefExpr::create(Symbol, VK_None, Ctx);
}
static const MCSymbolRefExpr *create(const MCSymbol *Symbol, VariantKind Kind,
MCContext &Ctx, SMLoc Loc = SMLoc());
static const MCSymbolRefExpr *create(StringRef Name, VariantKind Kind,
MCContext &Ctx);
/// @}
/// \name Accessors
/// @{
const MCSymbol &getSymbol() const { return *Symbol; }
VariantKind getKind() const {
return (VariantKind)(getSubclassData() & VariantKindMask);
}
bool hasSubsectionsViaSymbols() const {
return (getSubclassData() & HasSubsectionsViaSymbolsBit) != 0;
}
/// @}
/// \name Static Utility Functions
/// @{
static StringRef getVariantKindName(VariantKind Kind);
static VariantKind getVariantKindForName(StringRef Name);
/// @}
static bool classof(const MCExpr *E) {
return E->getKind() == MCExpr::SymbolRef;
}
};
/// Unary assembler expressions.
class MCUnaryExpr : public MCExpr {
public:
enum Opcode {
LNot, ///< Logical negation.
Minus, ///< Unary minus.
Not, ///< Bitwise negation.
Plus ///< Unary plus.
};
private:
const MCExpr *Expr;
MCUnaryExpr(Opcode Op, const MCExpr *Expr, SMLoc Loc)
: MCExpr(MCExpr::Unary, Loc, Op), Expr(Expr) {}
public:
/// \name Construction
/// @{
static const MCUnaryExpr *create(Opcode Op, const MCExpr *Expr,
MCContext &Ctx, SMLoc Loc = SMLoc());
static const MCUnaryExpr *createLNot(const MCExpr *Expr, MCContext &Ctx, SMLoc Loc = SMLoc()) {
return create(LNot, Expr, Ctx, Loc);
}
static const MCUnaryExpr *createMinus(const MCExpr *Expr, MCContext &Ctx, SMLoc Loc = SMLoc()) {
return create(Minus, Expr, Ctx, Loc);
}
static const MCUnaryExpr *createNot(const MCExpr *Expr, MCContext &Ctx, SMLoc Loc = SMLoc()) {
return create(Not, Expr, Ctx, Loc);
}
static const MCUnaryExpr *createPlus(const MCExpr *Expr, MCContext &Ctx, SMLoc Loc = SMLoc()) {
return create(Plus, Expr, Ctx, Loc);
}
/// @}
/// \name Accessors
/// @{
/// Get the kind of this unary expression.
Opcode getOpcode() const { return (Opcode)getSubclassData(); }
/// Get the child of this unary expression.
const MCExpr *getSubExpr() const { return Expr; }
/// @}
static bool classof(const MCExpr *E) {
return E->getKind() == MCExpr::Unary;
}
};
/// Binary assembler expressions.
class MCBinaryExpr : public MCExpr {
public:
enum Opcode {
Add, ///< Addition.
And, ///< Bitwise and.
Div, ///< Signed division.
EQ, ///< Equality comparison.
GT, ///< Signed greater than comparison (result is either 0 or some
///< target-specific non-zero value)
GTE, ///< Signed greater than or equal comparison (result is either 0 or
///< some target-specific non-zero value).
LAnd, ///< Logical and.
LOr, ///< Logical or.
LT, ///< Signed less than comparison (result is either 0 or
///< some target-specific non-zero value).
LTE, ///< Signed less than or equal comparison (result is either 0 or
///< some target-specific non-zero value).
Mod, ///< Signed remainder.
Mul, ///< Multiplication.
NE, ///< Inequality comparison.
Or, ///< Bitwise or.
OrNot, ///< Bitwise or not.
Shl, ///< Shift left.
AShr, ///< Arithmetic shift right.
LShr, ///< Logical shift right.
Sub, ///< Subtraction.
Xor ///< Bitwise exclusive or.
};
private:
const MCExpr *LHS, *RHS;
MCBinaryExpr(Opcode Op, const MCExpr *LHS, const MCExpr *RHS,
SMLoc Loc = SMLoc())
: MCExpr(MCExpr::Binary, Loc, Op), LHS(LHS), RHS(RHS) {}
public:
/// \name Construction
/// @{
static const MCBinaryExpr *create(Opcode Op, const MCExpr *LHS,
const MCExpr *RHS, MCContext &Ctx,
SMLoc Loc = SMLoc());
static const MCBinaryExpr *createAdd(const MCExpr *LHS, const MCExpr *RHS,
MCContext &Ctx) {
return create(Add, LHS, RHS, Ctx);
}
static const MCBinaryExpr *createAnd(const MCExpr *LHS, const MCExpr *RHS,
MCContext &Ctx) {
return create(And, LHS, RHS, Ctx);
}
static const MCBinaryExpr *createDiv(const MCExpr *LHS, const MCExpr *RHS,
MCContext &Ctx) {
return create(Div, LHS, RHS, Ctx);
}
static const MCBinaryExpr *createEQ(const MCExpr *LHS, const MCExpr *RHS,
MCContext &Ctx) {
return create(EQ, LHS, RHS, Ctx);
}
static const MCBinaryExpr *createGT(const MCExpr *LHS, const MCExpr *RHS,
MCContext &Ctx) {
return create(GT, LHS, RHS, Ctx);
}
static const MCBinaryExpr *createGTE(const MCExpr *LHS, const MCExpr *RHS,
MCContext &Ctx) {
return create(GTE, LHS, RHS, Ctx);
}
static const MCBinaryExpr *createLAnd(const MCExpr *LHS, const MCExpr *RHS,
MCContext &Ctx) {
return create(LAnd, LHS, RHS, Ctx);
}
static const MCBinaryExpr *createLOr(const MCExpr *LHS, const MCExpr *RHS,
MCContext &Ctx) {
return create(LOr, LHS, RHS, Ctx);
}
static const MCBinaryExpr *createLT(const MCExpr *LHS, const MCExpr *RHS,
MCContext &Ctx) {
return create(LT, LHS, RHS, Ctx);
}
static const MCBinaryExpr *createLTE(const MCExpr *LHS, const MCExpr *RHS,
MCContext &Ctx) {
return create(LTE, LHS, RHS, Ctx);
}
static const MCBinaryExpr *createMod(const MCExpr *LHS, const MCExpr *RHS,
MCContext &Ctx) {
return create(Mod, LHS, RHS, Ctx);
}
static const MCBinaryExpr *createMul(const MCExpr *LHS, const MCExpr *RHS,
MCContext &Ctx) {
return create(Mul, LHS, RHS, Ctx);
}
static const MCBinaryExpr *createNE(const MCExpr *LHS, const MCExpr *RHS,
MCContext &Ctx) {
return create(NE, LHS, RHS, Ctx);
}
static const MCBinaryExpr *createOr(const MCExpr *LHS, const MCExpr *RHS,
MCContext &Ctx) {
return create(Or, LHS, RHS, Ctx);
}
static const MCBinaryExpr *createShl(const MCExpr *LHS, const MCExpr *RHS,
MCContext &Ctx) {
return create(Shl, LHS, RHS, Ctx);
}
static const MCBinaryExpr *createAShr(const MCExpr *LHS, const MCExpr *RHS,
MCContext &Ctx) {
return create(AShr, LHS, RHS, Ctx);
}
static const MCBinaryExpr *createLShr(const MCExpr *LHS, const MCExpr *RHS,
MCContext &Ctx) {
return create(LShr, LHS, RHS, Ctx);
}
static const MCBinaryExpr *createSub(const MCExpr *LHS, const MCExpr *RHS,
MCContext &Ctx) {
return create(Sub, LHS, RHS, Ctx);
}
static const MCBinaryExpr *createXor(const MCExpr *LHS, const MCExpr *RHS,
MCContext &Ctx) {
return create(Xor, LHS, RHS, Ctx);
}
/// @}
/// \name Accessors
/// @{
/// Get the kind of this binary expression.
Opcode getOpcode() const { return (Opcode)getSubclassData(); }
/// Get the left-hand side expression of the binary operator.
const MCExpr *getLHS() const { return LHS; }
/// Get the right-hand side expression of the binary operator.
const MCExpr *getRHS() const { return RHS; }
/// @}
static bool classof(const MCExpr *E) {
return E->getKind() == MCExpr::Binary;
}
};
/// This is an extension point for target-specific MCExpr subclasses to
/// implement.
///
/// NOTE: All subclasses are required to have trivial destructors because
/// MCExprs are bump pointer allocated and not destructed.
class MCTargetExpr : public MCExpr {
virtual void anchor();
protected:
MCTargetExpr() : MCExpr(Target, SMLoc()) {}
virtual ~MCTargetExpr() = default;
public:
virtual void printImpl(raw_ostream &OS, const MCAsmInfo *MAI) const = 0;
virtual bool evaluateAsRelocatableImpl(MCValue &Res,
const MCAsmLayout *Layout,
const MCFixup *Fixup) const = 0;
// allow Target Expressions to be checked for equality
virtual bool isEqualTo(const MCExpr *x) const { return false; }
// This should be set when assigned expressions are not valid ".set"
// expressions, e.g. registers, and must be inlined.
virtual bool inlineAssignedExpr() const { return false; }
virtual void visitUsedExpr(MCStreamer& Streamer) const = 0;
virtual MCFragment *findAssociatedFragment() const = 0;
virtual void fixELFSymbolsInTLSFixups(MCAssembler &) const = 0;
static bool classof(const MCExpr *E) {
return E->getKind() == MCExpr::Target;
}
};
} // end namespace llvm
#endif // LLVM_MC_MCEXPR_H
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