//===- MCExpr.h - Assembly Level Expressions --------------------*- C++ -*-===// // // The LLVM Compiler Infrastructure // // This file is distributed under the University of Illinois Open Source // License. See LICENSE.TXT for details. // //===----------------------------------------------------------------------===// #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>; /// \brief Base class for the full range of assembler expressions which are /// needed for parsing. class MCExpr { public: enum ExprKind { Binary, ///< Binary expressions. Constant, ///< Constant expressions. SymbolRef, ///< References to labels and assigned expressions. Unary, ///< Unary expressions. Target ///< Target specific expression. }; private: ExprKind Kind; SMLoc Loc; bool evaluateAsAbsolute(int64_t &Res, const MCAssembler *Asm, const MCAsmLayout *Layout, const SectionAddrMap *Addrs) const; bool evaluateAsAbsolute(int64_t &Res, const MCAssembler *Asm, const MCAsmLayout *Layout, const SectionAddrMap *Addrs, bool InSet) const; protected: explicit MCExpr(ExprKind Kind, SMLoc Loc) : Kind(Kind), Loc(Loc) {} bool evaluateAsRelocatableImpl(MCValue &Res, const MCAssembler *Asm, const MCAsmLayout *Layout, const MCFixup *Fixup, const SectionAddrMap *Addrs, bool InSet) const; 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 /// @{ /// \brief 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 MCAsmLayout &Layout) const; bool evaluateKnownAbsolute(int64_t &Res, const MCAsmLayout &Layout) const; /// \brief 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; /// \brief 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; /// \brief 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; } //// \brief Represent a constant integer expression. class MCConstantExpr : public MCExpr { int64_t Value; explicit MCConstantExpr(int64_t Value) : MCExpr(MCExpr::Constant, SMLoc()), Value(Value) {} public: /// \name Construction /// @{ static const MCConstantExpr *create(int64_t Value, MCContext &Ctx); /// @} /// \name Accessors /// @{ int64_t getValue() const { return Value; } /// @} static bool classof(const MCExpr *E) { return E->getKind() == MCExpr::Constant; } }; /// \brief 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_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_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_PPC_LO, // symbol@l VK_PPC_HI, // symbol@h VK_PPC_HA, // symbol@ha 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_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_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_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_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_TLSLD, // symbol@tlsld VK_PPC_LOCAL, // symbol@local VK_COFF_IMGREL32, // symbol@imgrel (image-relative) VK_Hexagon_PCREL, 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_WebAssembly_FUNCTION, // Function table index, rather than virtual addr VK_WebAssembly_TYPEINDEX,// Type table index 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_TPREL, VK_DTPREL }; private: /// The symbol reference modifier. const VariantKind Kind; /// Specifies how the variant kind should be printed. const unsigned UseParensForSymbolVariant : 1; // FIXME: Remove this bit. const unsigned HasSubsectionsViaSymbols : 1; /// The symbol being referenced. const MCSymbol *Symbol; 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 Kind; } void printVariantKind(raw_ostream &OS) const; bool hasSubsectionsViaSymbols() const { return HasSubsectionsViaSymbols; } /// @} /// \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; } }; /// \brief Unary assembler expressions. class MCUnaryExpr : public MCExpr { public: enum Opcode { LNot, ///< Logical negation. Minus, ///< Unary minus. Not, ///< Bitwise negation. Plus ///< Unary plus. }; private: Opcode Op; const MCExpr *Expr; MCUnaryExpr(Opcode Op, const MCExpr *Expr, SMLoc Loc) : MCExpr(MCExpr::Unary, Loc), Op(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 /// @{ /// \brief Get the kind of this unary expression. Opcode getOpcode() const { return Op; } /// \brief Get the child of this unary expression. const MCExpr *getSubExpr() const { return Expr; } /// @} static bool classof(const MCExpr *E) { return E->getKind() == MCExpr::Unary; } }; /// \brief 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. Shl, ///< Shift left. AShr, ///< Arithmetic shift right. LShr, ///< Logical shift right. Sub, ///< Subtraction. Xor ///< Bitwise exclusive or. }; private: Opcode Op; const MCExpr *LHS, *RHS; MCBinaryExpr(Opcode Op, const MCExpr *LHS, const MCExpr *RHS, SMLoc Loc = SMLoc()) : MCExpr(MCExpr::Binary, Loc), Op(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 /// @{ /// \brief Get the kind of this binary expression. Opcode getOpcode() const { return Op; } /// \brief Get the left-hand side expression of the binary operator. const MCExpr *getLHS() const { return LHS; } /// \brief 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; } }; /// \brief 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; 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