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  1. //===- MCExpr.h - Assembly Level Expressions --------------------*- C++ -*-===//
  2. //
  3. // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
  4. // See https://llvm.org/LICENSE.txt for license information.
  5. // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
  6. //
  7. //===----------------------------------------------------------------------===//
  8.  
  9. #ifndef LLVM_MC_MCEXPR_H
  10. #define LLVM_MC_MCEXPR_H
  11.  
  12. #include "llvm/ADT/DenseMap.h"
  13. #include "llvm/Support/SMLoc.h"
  14. #include <cstdint>
  15.  
  16. namespace llvm {
  17.  
  18. class MCAsmInfo;
  19. class MCAsmLayout;
  20. class MCAssembler;
  21. class MCContext;
  22. class MCFixup;
  23. class MCFragment;
  24. class MCSection;
  25. class MCStreamer;
  26. class MCSymbol;
  27. class MCValue;
  28. class raw_ostream;
  29. class StringRef;
  30.  
  31. using SectionAddrMap = DenseMap<const MCSection *, uint64_t>;
  32.  
  33. /// Base class for the full range of assembler expressions which are
  34. /// needed for parsing.
  35. class MCExpr {
  36. public:
  37.   enum ExprKind : uint8_t {
  38.     Binary,    ///< Binary expressions.
  39.     Constant,  ///< Constant expressions.
  40.     SymbolRef, ///< References to labels and assigned expressions.
  41.     Unary,     ///< Unary expressions.
  42.     Target     ///< Target specific expression.
  43.   };
  44.  
  45. private:
  46.   static const unsigned NumSubclassDataBits = 24;
  47.   static_assert(
  48.       NumSubclassDataBits == CHAR_BIT * (sizeof(unsigned) - sizeof(ExprKind)),
  49.       "ExprKind and SubclassData together should take up one word");
  50.  
  51.   ExprKind Kind;
  52.   /// Field reserved for use by MCExpr subclasses.
  53.   unsigned SubclassData : NumSubclassDataBits;
  54.   SMLoc Loc;
  55.  
  56.   bool evaluateAsAbsolute(int64_t &Res, const MCAssembler *Asm,
  57.                           const MCAsmLayout *Layout,
  58.                           const SectionAddrMap *Addrs, bool InSet) const;
  59.  
  60. protected:
  61.   explicit MCExpr(ExprKind Kind, SMLoc Loc, unsigned SubclassData = 0)
  62.       : Kind(Kind), SubclassData(SubclassData), Loc(Loc) {
  63.     assert(SubclassData < (1 << NumSubclassDataBits) &&
  64.            "Subclass data too large");
  65.   }
  66.  
  67.   bool evaluateAsRelocatableImpl(MCValue &Res, const MCAssembler *Asm,
  68.                                  const MCAsmLayout *Layout,
  69.                                  const MCFixup *Fixup,
  70.                                  const SectionAddrMap *Addrs, bool InSet) const;
  71.  
  72.   unsigned getSubclassData() const { return SubclassData; }
  73.  
  74. public:
  75.   MCExpr(const MCExpr &) = delete;
  76.   MCExpr &operator=(const MCExpr &) = delete;
  77.  
  78.   /// \name Accessors
  79.   /// @{
  80.  
  81.   ExprKind getKind() const { return Kind; }
  82.   SMLoc getLoc() const { return Loc; }
  83.  
  84.   /// @}
  85.   /// \name Utility Methods
  86.   /// @{
  87.  
  88.   void print(raw_ostream &OS, const MCAsmInfo *MAI,
  89.              bool InParens = false) const;
  90.   void dump() const;
  91.  
  92.   /// @}
  93.   /// \name Expression Evaluation
  94.   /// @{
  95.  
  96.   /// Try to evaluate the expression to an absolute value.
  97.   ///
  98.   /// \param Res - The absolute value, if evaluation succeeds.
  99.   /// \param Layout - The assembler layout object to use for evaluating symbol
  100.   /// values. If not given, then only non-symbolic expressions will be
  101.   /// evaluated.
  102.   /// \return - True on success.
  103.   bool evaluateAsAbsolute(int64_t &Res, const MCAsmLayout &Layout,
  104.                           const SectionAddrMap &Addrs) const;
  105.   bool evaluateAsAbsolute(int64_t &Res) const;
  106.   bool evaluateAsAbsolute(int64_t &Res, const MCAssembler &Asm) const;
  107.   bool evaluateAsAbsolute(int64_t &Res, const MCAssembler *Asm) const;
  108.   bool evaluateAsAbsolute(int64_t &Res, const MCAsmLayout &Layout) const;
  109.  
  110.   bool evaluateKnownAbsolute(int64_t &Res, const MCAsmLayout &Layout) const;
  111.  
  112.   /// Try to evaluate the expression to a relocatable value, i.e. an
  113.   /// expression of the fixed form (a - b + constant).
  114.   ///
  115.   /// \param Res - The relocatable value, if evaluation succeeds.
  116.   /// \param Layout - The assembler layout object to use for evaluating values.
  117.   /// \param Fixup - The Fixup object if available.
  118.   /// \return - True on success.
  119.   bool evaluateAsRelocatable(MCValue &Res, const MCAsmLayout *Layout,
  120.                              const MCFixup *Fixup) const;
  121.  
  122.   /// Try to evaluate the expression to the form (a - b + constant) where
  123.   /// neither a nor b are variables.
  124.   ///
  125.   /// This is a more aggressive variant of evaluateAsRelocatable. The intended
  126.   /// use is for when relocations are not available, like the .size directive.
  127.   bool evaluateAsValue(MCValue &Res, const MCAsmLayout &Layout) const;
  128.  
  129.   /// Find the "associated section" for this expression, which is
  130.   /// currently defined as the absolute section for constants, or
  131.   /// otherwise the section associated with the first defined symbol in the
  132.   /// expression.
  133.   MCFragment *findAssociatedFragment() const;
  134.  
  135.   /// @}
  136. };
  137.  
  138. inline raw_ostream &operator<<(raw_ostream &OS, const MCExpr &E) {
  139.   E.print(OS, nullptr);
  140.   return OS;
  141. }
  142.  
  143. ////  Represent a constant integer expression.
  144. class MCConstantExpr : public MCExpr {
  145.   int64_t Value;
  146.  
  147.   // Subclass data stores SizeInBytes in bits 0..7 and PrintInHex in bit 8.
  148.   static const unsigned SizeInBytesBits = 8;
  149.   static const unsigned SizeInBytesMask = (1 << SizeInBytesBits) - 1;
  150.   static const unsigned PrintInHexBit = 1 << SizeInBytesBits;
  151.  
  152.   static unsigned encodeSubclassData(bool PrintInHex, unsigned SizeInBytes) {
  153.     assert(SizeInBytes <= sizeof(int64_t) && "Excessive size");
  154.     return SizeInBytes | (PrintInHex ? PrintInHexBit : 0);
  155.   }
  156.  
  157.   MCConstantExpr(int64_t Value, bool PrintInHex, unsigned SizeInBytes)
  158.       : MCExpr(MCExpr::Constant, SMLoc(),
  159.                encodeSubclassData(PrintInHex, SizeInBytes)), Value(Value) {}
  160.  
  161. public:
  162.   /// \name Construction
  163.   /// @{
  164.  
  165.   static const MCConstantExpr *create(int64_t Value, MCContext &Ctx,
  166.                                       bool PrintInHex = false,
  167.                                       unsigned SizeInBytes = 0);
  168.  
  169.   /// @}
  170.   /// \name Accessors
  171.   /// @{
  172.  
  173.   int64_t getValue() const { return Value; }
  174.   unsigned getSizeInBytes() const {
  175.     return getSubclassData() & SizeInBytesMask;
  176.   }
  177.  
  178.   bool useHexFormat() const { return (getSubclassData() & PrintInHexBit) != 0; }
  179.  
  180.   /// @}
  181.  
  182.   static bool classof(const MCExpr *E) {
  183.     return E->getKind() == MCExpr::Constant;
  184.   }
  185. };
  186.  
  187. ///  Represent a reference to a symbol from inside an expression.
  188. ///
  189. /// A symbol reference in an expression may be a use of a label, a use of an
  190. /// assembler variable (defined constant), or constitute an implicit definition
  191. /// of the symbol as external.
  192. class MCSymbolRefExpr : public MCExpr {
  193. public:
  194.   enum VariantKind : uint16_t {
  195.     VK_None,
  196.     VK_Invalid,
  197.  
  198.     VK_GOT,
  199.     VK_GOTOFF,
  200.     VK_GOTREL,
  201.     VK_PCREL,
  202.     VK_GOTPCREL,
  203.     VK_GOTPCREL_NORELAX,
  204.     VK_GOTTPOFF,
  205.     VK_INDNTPOFF,
  206.     VK_NTPOFF,
  207.     VK_GOTNTPOFF,
  208.     VK_PLT,
  209.     VK_TLSGD,
  210.     VK_TLSLD,
  211.     VK_TLSLDM,
  212.     VK_TPOFF,
  213.     VK_DTPOFF,
  214.     VK_TLSCALL, // symbol(tlscall)
  215.     VK_TLSDESC, // symbol(tlsdesc)
  216.     VK_TLVP,    // Mach-O thread local variable relocations
  217.     VK_TLVPPAGE,
  218.     VK_TLVPPAGEOFF,
  219.     VK_PAGE,
  220.     VK_PAGEOFF,
  221.     VK_GOTPAGE,
  222.     VK_GOTPAGEOFF,
  223.     VK_SECREL,
  224.     VK_SIZE,    // symbol@SIZE
  225.     VK_WEAKREF, // The link between the symbols in .weakref foo, bar
  226.  
  227.     VK_X86_ABS8,
  228.     VK_X86_PLTOFF,
  229.  
  230.     VK_ARM_NONE,
  231.     VK_ARM_GOT_PREL,
  232.     VK_ARM_TARGET1,
  233.     VK_ARM_TARGET2,
  234.     VK_ARM_PREL31,
  235.     VK_ARM_SBREL,  // symbol(sbrel)
  236.     VK_ARM_TLSLDO, // symbol(tlsldo)
  237.     VK_ARM_TLSDESCSEQ,
  238.  
  239.     VK_AVR_NONE,
  240.     VK_AVR_LO8,
  241.     VK_AVR_HI8,
  242.     VK_AVR_HLO8,
  243.     VK_AVR_DIFF8,
  244.     VK_AVR_DIFF16,
  245.     VK_AVR_DIFF32,
  246.     VK_AVR_PM,
  247.  
  248.     VK_PPC_LO,              // symbol@l
  249.     VK_PPC_HI,              // symbol@h
  250.     VK_PPC_HA,              // symbol@ha
  251.     VK_PPC_HIGH,            // symbol@high
  252.     VK_PPC_HIGHA,           // symbol@higha
  253.     VK_PPC_HIGHER,          // symbol@higher
  254.     VK_PPC_HIGHERA,         // symbol@highera
  255.     VK_PPC_HIGHEST,         // symbol@highest
  256.     VK_PPC_HIGHESTA,        // symbol@highesta
  257.     VK_PPC_GOT_LO,          // symbol@got@l
  258.     VK_PPC_GOT_HI,          // symbol@got@h
  259.     VK_PPC_GOT_HA,          // symbol@got@ha
  260.     VK_PPC_TOCBASE,         // symbol@tocbase
  261.     VK_PPC_TOC,             // symbol@toc
  262.     VK_PPC_TOC_LO,          // symbol@toc@l
  263.     VK_PPC_TOC_HI,          // symbol@toc@h
  264.     VK_PPC_TOC_HA,          // symbol@toc@ha
  265.     VK_PPC_U,               // symbol@u
  266.     VK_PPC_L,               // symbol@l
  267.     VK_PPC_DTPMOD,          // symbol@dtpmod
  268.     VK_PPC_TPREL_LO,        // symbol@tprel@l
  269.     VK_PPC_TPREL_HI,        // symbol@tprel@h
  270.     VK_PPC_TPREL_HA,        // symbol@tprel@ha
  271.     VK_PPC_TPREL_HIGH,      // symbol@tprel@high
  272.     VK_PPC_TPREL_HIGHA,     // symbol@tprel@higha
  273.     VK_PPC_TPREL_HIGHER,    // symbol@tprel@higher
  274.     VK_PPC_TPREL_HIGHERA,   // symbol@tprel@highera
  275.     VK_PPC_TPREL_HIGHEST,   // symbol@tprel@highest
  276.     VK_PPC_TPREL_HIGHESTA,  // symbol@tprel@highesta
  277.     VK_PPC_DTPREL_LO,       // symbol@dtprel@l
  278.     VK_PPC_DTPREL_HI,       // symbol@dtprel@h
  279.     VK_PPC_DTPREL_HA,       // symbol@dtprel@ha
  280.     VK_PPC_DTPREL_HIGH,     // symbol@dtprel@high
  281.     VK_PPC_DTPREL_HIGHA,    // symbol@dtprel@higha
  282.     VK_PPC_DTPREL_HIGHER,   // symbol@dtprel@higher
  283.     VK_PPC_DTPREL_HIGHERA,  // symbol@dtprel@highera
  284.     VK_PPC_DTPREL_HIGHEST,  // symbol@dtprel@highest
  285.     VK_PPC_DTPREL_HIGHESTA, // symbol@dtprel@highesta
  286.     VK_PPC_GOT_TPREL,       // symbol@got@tprel
  287.     VK_PPC_GOT_TPREL_LO,    // symbol@got@tprel@l
  288.     VK_PPC_GOT_TPREL_HI,    // symbol@got@tprel@h
  289.     VK_PPC_GOT_TPREL_HA,    // symbol@got@tprel@ha
  290.     VK_PPC_GOT_DTPREL,      // symbol@got@dtprel
  291.     VK_PPC_GOT_DTPREL_LO,   // symbol@got@dtprel@l
  292.     VK_PPC_GOT_DTPREL_HI,   // symbol@got@dtprel@h
  293.     VK_PPC_GOT_DTPREL_HA,   // symbol@got@dtprel@ha
  294.     VK_PPC_TLS,             // symbol@tls
  295.     VK_PPC_GOT_TLSGD,       // symbol@got@tlsgd
  296.     VK_PPC_GOT_TLSGD_LO,    // symbol@got@tlsgd@l
  297.     VK_PPC_GOT_TLSGD_HI,    // symbol@got@tlsgd@h
  298.     VK_PPC_GOT_TLSGD_HA,    // symbol@got@tlsgd@ha
  299.     VK_PPC_TLSGD,           // symbol@tlsgd
  300.     VK_PPC_AIX_TLSGD,       // symbol@gd
  301.     VK_PPC_AIX_TLSGDM,      // symbol@m
  302.     VK_PPC_GOT_TLSLD,       // symbol@got@tlsld
  303.     VK_PPC_GOT_TLSLD_LO,    // symbol@got@tlsld@l
  304.     VK_PPC_GOT_TLSLD_HI,    // symbol@got@tlsld@h
  305.     VK_PPC_GOT_TLSLD_HA,    // symbol@got@tlsld@ha
  306.     VK_PPC_GOT_PCREL,       // symbol@got@pcrel
  307.     VK_PPC_GOT_TLSGD_PCREL, // symbol@got@tlsgd@pcrel
  308.     VK_PPC_GOT_TLSLD_PCREL, // symbol@got@tlsld@pcrel
  309.     VK_PPC_GOT_TPREL_PCREL, // symbol@got@tprel@pcrel
  310.     VK_PPC_TLS_PCREL,       // symbol@tls@pcrel
  311.     VK_PPC_TLSLD,           // symbol@tlsld
  312.     VK_PPC_LOCAL,           // symbol@local
  313.     VK_PPC_NOTOC,           // symbol@notoc
  314.     VK_PPC_PCREL_OPT,       // .reloc expr, R_PPC64_PCREL_OPT, expr
  315.  
  316.     VK_COFF_IMGREL32, // symbol@imgrel (image-relative)
  317.  
  318.     VK_Hexagon_LO16,
  319.     VK_Hexagon_HI16,
  320.     VK_Hexagon_GPREL,
  321.     VK_Hexagon_GD_GOT,
  322.     VK_Hexagon_LD_GOT,
  323.     VK_Hexagon_GD_PLT,
  324.     VK_Hexagon_LD_PLT,
  325.     VK_Hexagon_IE,
  326.     VK_Hexagon_IE_GOT,
  327.  
  328.     VK_WASM_TYPEINDEX, // Reference to a symbol's type (signature)
  329.     VK_WASM_TLSREL,    // Memory address relative to __tls_base
  330.     VK_WASM_MBREL,     // Memory address relative to __memory_base
  331.     VK_WASM_TBREL,     // Table index relative to __table_base
  332.     VK_WASM_GOT_TLS,   // Wasm global index of TLS symbol.
  333.  
  334.     VK_AMDGPU_GOTPCREL32_LO, // symbol@gotpcrel32@lo
  335.     VK_AMDGPU_GOTPCREL32_HI, // symbol@gotpcrel32@hi
  336.     VK_AMDGPU_REL32_LO,      // symbol@rel32@lo
  337.     VK_AMDGPU_REL32_HI,      // symbol@rel32@hi
  338.     VK_AMDGPU_REL64,         // symbol@rel64
  339.     VK_AMDGPU_ABS32_LO,      // symbol@abs32@lo
  340.     VK_AMDGPU_ABS32_HI,      // symbol@abs32@hi
  341.  
  342.     VK_VE_HI32,        // symbol@hi
  343.     VK_VE_LO32,        // symbol@lo
  344.     VK_VE_PC_HI32,     // symbol@pc_hi
  345.     VK_VE_PC_LO32,     // symbol@pc_lo
  346.     VK_VE_GOT_HI32,    // symbol@got_hi
  347.     VK_VE_GOT_LO32,    // symbol@got_lo
  348.     VK_VE_GOTOFF_HI32, // symbol@gotoff_hi
  349.     VK_VE_GOTOFF_LO32, // symbol@gotoff_lo
  350.     VK_VE_PLT_HI32,    // symbol@plt_hi
  351.     VK_VE_PLT_LO32,    // symbol@plt_lo
  352.     VK_VE_TLS_GD_HI32, // symbol@tls_gd_hi
  353.     VK_VE_TLS_GD_LO32, // symbol@tls_gd_lo
  354.     VK_VE_TPOFF_HI32,  // symbol@tpoff_hi
  355.     VK_VE_TPOFF_LO32,  // symbol@tpoff_lo
  356.  
  357.     VK_TPREL,
  358.     VK_DTPREL
  359.   };
  360.  
  361. private:
  362.   /// The symbol being referenced.
  363.   const MCSymbol *Symbol;
  364.  
  365.   // Subclass data stores VariantKind in bits 0..15 and HasSubsectionsViaSymbols
  366.   // in bit 16.
  367.   static const unsigned VariantKindBits = 16;
  368.   static const unsigned VariantKindMask = (1 << VariantKindBits) - 1;
  369.  
  370.   // FIXME: Remove this bit.
  371.   static const unsigned HasSubsectionsViaSymbolsBit = 1 << VariantKindBits;
  372.  
  373.   static unsigned encodeSubclassData(VariantKind Kind,
  374.                                      bool HasSubsectionsViaSymbols) {
  375.     return (unsigned)Kind |
  376.            (HasSubsectionsViaSymbols ? HasSubsectionsViaSymbolsBit : 0);
  377.   }
  378.  
  379.   explicit MCSymbolRefExpr(const MCSymbol *Symbol, VariantKind Kind,
  380.                            const MCAsmInfo *MAI, SMLoc Loc = SMLoc());
  381.  
  382. public:
  383.   /// \name Construction
  384.   /// @{
  385.  
  386.   static const MCSymbolRefExpr *create(const MCSymbol *Symbol, MCContext &Ctx) {
  387.     return MCSymbolRefExpr::create(Symbol, VK_None, Ctx);
  388.   }
  389.  
  390.   static const MCSymbolRefExpr *create(const MCSymbol *Symbol, VariantKind Kind,
  391.                                        MCContext &Ctx, SMLoc Loc = SMLoc());
  392.   static const MCSymbolRefExpr *create(StringRef Name, VariantKind Kind,
  393.                                        MCContext &Ctx);
  394.  
  395.   /// @}
  396.   /// \name Accessors
  397.   /// @{
  398.  
  399.   const MCSymbol &getSymbol() const { return *Symbol; }
  400.  
  401.   VariantKind getKind() const {
  402.     return (VariantKind)(getSubclassData() & VariantKindMask);
  403.   }
  404.  
  405.   bool hasSubsectionsViaSymbols() const {
  406.     return (getSubclassData() & HasSubsectionsViaSymbolsBit) != 0;
  407.   }
  408.  
  409.   /// @}
  410.   /// \name Static Utility Functions
  411.   /// @{
  412.  
  413.   static StringRef getVariantKindName(VariantKind Kind);
  414.  
  415.   static VariantKind getVariantKindForName(StringRef Name);
  416.  
  417.   /// @}
  418.  
  419.   static bool classof(const MCExpr *E) {
  420.     return E->getKind() == MCExpr::SymbolRef;
  421.   }
  422. };
  423.  
  424. /// Unary assembler expressions.
  425. class MCUnaryExpr : public MCExpr {
  426. public:
  427.   enum Opcode {
  428.     LNot,  ///< Logical negation.
  429.     Minus, ///< Unary minus.
  430.     Not,   ///< Bitwise negation.
  431.     Plus   ///< Unary plus.
  432.   };
  433.  
  434. private:
  435.   const MCExpr *Expr;
  436.  
  437.   MCUnaryExpr(Opcode Op, const MCExpr *Expr, SMLoc Loc)
  438.       : MCExpr(MCExpr::Unary, Loc, Op), Expr(Expr) {}
  439.  
  440. public:
  441.   /// \name Construction
  442.   /// @{
  443.  
  444.   static const MCUnaryExpr *create(Opcode Op, const MCExpr *Expr,
  445.                                    MCContext &Ctx, SMLoc Loc = SMLoc());
  446.  
  447.   static const MCUnaryExpr *createLNot(const MCExpr *Expr, MCContext &Ctx, SMLoc Loc = SMLoc()) {
  448.     return create(LNot, Expr, Ctx, Loc);
  449.   }
  450.  
  451.   static const MCUnaryExpr *createMinus(const MCExpr *Expr, MCContext &Ctx, SMLoc Loc = SMLoc()) {
  452.     return create(Minus, Expr, Ctx, Loc);
  453.   }
  454.  
  455.   static const MCUnaryExpr *createNot(const MCExpr *Expr, MCContext &Ctx, SMLoc Loc = SMLoc()) {
  456.     return create(Not, Expr, Ctx, Loc);
  457.   }
  458.  
  459.   static const MCUnaryExpr *createPlus(const MCExpr *Expr, MCContext &Ctx, SMLoc Loc = SMLoc()) {
  460.     return create(Plus, Expr, Ctx, Loc);
  461.   }
  462.  
  463.   /// @}
  464.   /// \name Accessors
  465.   /// @{
  466.  
  467.   /// Get the kind of this unary expression.
  468.   Opcode getOpcode() const { return (Opcode)getSubclassData(); }
  469.  
  470.   /// Get the child of this unary expression.
  471.   const MCExpr *getSubExpr() const { return Expr; }
  472.  
  473.   /// @}
  474.  
  475.   static bool classof(const MCExpr *E) {
  476.     return E->getKind() == MCExpr::Unary;
  477.   }
  478. };
  479.  
  480. /// Binary assembler expressions.
  481. class MCBinaryExpr : public MCExpr {
  482. public:
  483.   enum Opcode {
  484.     Add,  ///< Addition.
  485.     And,  ///< Bitwise and.
  486.     Div,  ///< Signed division.
  487.     EQ,   ///< Equality comparison.
  488.     GT,   ///< Signed greater than comparison (result is either 0 or some
  489.           ///< target-specific non-zero value)
  490.     GTE,  ///< Signed greater than or equal comparison (result is either 0 or
  491.           ///< some target-specific non-zero value).
  492.     LAnd, ///< Logical and.
  493.     LOr,  ///< Logical or.
  494.     LT,   ///< Signed less than comparison (result is either 0 or
  495.           ///< some target-specific non-zero value).
  496.     LTE,  ///< Signed less than or equal comparison (result is either 0 or
  497.           ///< some target-specific non-zero value).
  498.     Mod,  ///< Signed remainder.
  499.     Mul,  ///< Multiplication.
  500.     NE,   ///< Inequality comparison.
  501.     Or,   ///< Bitwise or.
  502.     OrNot, ///< Bitwise or not.
  503.     Shl,  ///< Shift left.
  504.     AShr, ///< Arithmetic shift right.
  505.     LShr, ///< Logical shift right.
  506.     Sub,  ///< Subtraction.
  507.     Xor   ///< Bitwise exclusive or.
  508.   };
  509.  
  510. private:
  511.   const MCExpr *LHS, *RHS;
  512.  
  513.   MCBinaryExpr(Opcode Op, const MCExpr *LHS, const MCExpr *RHS,
  514.                SMLoc Loc = SMLoc())
  515.       : MCExpr(MCExpr::Binary, Loc, Op), LHS(LHS), RHS(RHS) {}
  516.  
  517. public:
  518.   /// \name Construction
  519.   /// @{
  520.  
  521.   static const MCBinaryExpr *create(Opcode Op, const MCExpr *LHS,
  522.                                     const MCExpr *RHS, MCContext &Ctx,
  523.                                     SMLoc Loc = SMLoc());
  524.  
  525.   static const MCBinaryExpr *createAdd(const MCExpr *LHS, const MCExpr *RHS,
  526.                                        MCContext &Ctx) {
  527.     return create(Add, LHS, RHS, Ctx);
  528.   }
  529.  
  530.   static const MCBinaryExpr *createAnd(const MCExpr *LHS, const MCExpr *RHS,
  531.                                        MCContext &Ctx) {
  532.     return create(And, LHS, RHS, Ctx);
  533.   }
  534.  
  535.   static const MCBinaryExpr *createDiv(const MCExpr *LHS, const MCExpr *RHS,
  536.                                        MCContext &Ctx) {
  537.     return create(Div, LHS, RHS, Ctx);
  538.   }
  539.  
  540.   static const MCBinaryExpr *createEQ(const MCExpr *LHS, const MCExpr *RHS,
  541.                                       MCContext &Ctx) {
  542.     return create(EQ, LHS, RHS, Ctx);
  543.   }
  544.  
  545.   static const MCBinaryExpr *createGT(const MCExpr *LHS, const MCExpr *RHS,
  546.                                       MCContext &Ctx) {
  547.     return create(GT, LHS, RHS, Ctx);
  548.   }
  549.  
  550.   static const MCBinaryExpr *createGTE(const MCExpr *LHS, const MCExpr *RHS,
  551.                                        MCContext &Ctx) {
  552.     return create(GTE, LHS, RHS, Ctx);
  553.   }
  554.  
  555.   static const MCBinaryExpr *createLAnd(const MCExpr *LHS, const MCExpr *RHS,
  556.                                         MCContext &Ctx) {
  557.     return create(LAnd, LHS, RHS, Ctx);
  558.   }
  559.  
  560.   static const MCBinaryExpr *createLOr(const MCExpr *LHS, const MCExpr *RHS,
  561.                                        MCContext &Ctx) {
  562.     return create(LOr, LHS, RHS, Ctx);
  563.   }
  564.  
  565.   static const MCBinaryExpr *createLT(const MCExpr *LHS, const MCExpr *RHS,
  566.                                       MCContext &Ctx) {
  567.     return create(LT, LHS, RHS, Ctx);
  568.   }
  569.  
  570.   static const MCBinaryExpr *createLTE(const MCExpr *LHS, const MCExpr *RHS,
  571.                                        MCContext &Ctx) {
  572.     return create(LTE, LHS, RHS, Ctx);
  573.   }
  574.  
  575.   static const MCBinaryExpr *createMod(const MCExpr *LHS, const MCExpr *RHS,
  576.                                        MCContext &Ctx) {
  577.     return create(Mod, LHS, RHS, Ctx);
  578.   }
  579.  
  580.   static const MCBinaryExpr *createMul(const MCExpr *LHS, const MCExpr *RHS,
  581.                                        MCContext &Ctx) {
  582.     return create(Mul, LHS, RHS, Ctx);
  583.   }
  584.  
  585.   static const MCBinaryExpr *createNE(const MCExpr *LHS, const MCExpr *RHS,
  586.                                       MCContext &Ctx) {
  587.     return create(NE, LHS, RHS, Ctx);
  588.   }
  589.  
  590.   static const MCBinaryExpr *createOr(const MCExpr *LHS, const MCExpr *RHS,
  591.                                       MCContext &Ctx) {
  592.     return create(Or, LHS, RHS, Ctx);
  593.   }
  594.  
  595.   static const MCBinaryExpr *createShl(const MCExpr *LHS, const MCExpr *RHS,
  596.                                        MCContext &Ctx) {
  597.     return create(Shl, LHS, RHS, Ctx);
  598.   }
  599.  
  600.   static const MCBinaryExpr *createAShr(const MCExpr *LHS, const MCExpr *RHS,
  601.                                        MCContext &Ctx) {
  602.     return create(AShr, LHS, RHS, Ctx);
  603.   }
  604.  
  605.   static const MCBinaryExpr *createLShr(const MCExpr *LHS, const MCExpr *RHS,
  606.                                        MCContext &Ctx) {
  607.     return create(LShr, LHS, RHS, Ctx);
  608.   }
  609.  
  610.   static const MCBinaryExpr *createSub(const MCExpr *LHS, const MCExpr *RHS,
  611.                                        MCContext &Ctx) {
  612.     return create(Sub, LHS, RHS, Ctx);
  613.   }
  614.  
  615.   static const MCBinaryExpr *createXor(const MCExpr *LHS, const MCExpr *RHS,
  616.                                        MCContext &Ctx) {
  617.     return create(Xor, LHS, RHS, Ctx);
  618.   }
  619.  
  620.   /// @}
  621.   /// \name Accessors
  622.   /// @{
  623.  
  624.   /// Get the kind of this binary expression.
  625.   Opcode getOpcode() const { return (Opcode)getSubclassData(); }
  626.  
  627.   /// Get the left-hand side expression of the binary operator.
  628.   const MCExpr *getLHS() const { return LHS; }
  629.  
  630.   /// Get the right-hand side expression of the binary operator.
  631.   const MCExpr *getRHS() const { return RHS; }
  632.  
  633.   /// @}
  634.  
  635.   static bool classof(const MCExpr *E) {
  636.     return E->getKind() == MCExpr::Binary;
  637.   }
  638. };
  639.  
  640. /// This is an extension point for target-specific MCExpr subclasses to
  641. /// implement.
  642. ///
  643. /// NOTE: All subclasses are required to have trivial destructors because
  644. /// MCExprs are bump pointer allocated and not destructed.
  645. class MCTargetExpr : public MCExpr {
  646.   virtual void anchor();
  647.  
  648. protected:
  649.   MCTargetExpr() : MCExpr(Target, SMLoc()) {}
  650.   virtual ~MCTargetExpr() = default;
  651.  
  652. public:
  653.   virtual void printImpl(raw_ostream &OS, const MCAsmInfo *MAI) const = 0;
  654.   virtual bool evaluateAsRelocatableImpl(MCValue &Res,
  655.                                          const MCAsmLayout *Layout,
  656.                                          const MCFixup *Fixup) const = 0;
  657.   // allow Target Expressions to be checked for equality
  658.   virtual bool isEqualTo(const MCExpr *x) const { return false; }
  659.   // This should be set when assigned expressions are not valid ".set"
  660.   // expressions, e.g. registers, and must be inlined.
  661.   virtual bool inlineAssignedExpr() const { return false; }
  662.   virtual void visitUsedExpr(MCStreamer& Streamer) const = 0;
  663.   virtual MCFragment *findAssociatedFragment() const = 0;
  664.  
  665.   virtual void fixELFSymbolsInTLSFixups(MCAssembler &) const = 0;
  666.  
  667.   static bool classof(const MCExpr *E) {
  668.     return E->getKind() == MCExpr::Target;
  669.   }
  670. };
  671.  
  672. } // end namespace llvm
  673.  
  674. #endif // LLVM_MC_MCEXPR_H
  675.