lib/Target/ARM/ARMMCExpr.h

   1 //===-- ARMMCExpr.h - ARM specific MC expression classes ------------------===//
   2 //
   3 //                     The LLVM Compiler Infrastructure
   4 //
   5 // This file is distributed under the University of Illinois Open Source
   6 // License. See LICENSE.TXT for details.
   7 //
   8 //===----------------------------------------------------------------------===//
   9
  10 #ifndef ARMMCEXPR_H
  11 #define ARMMCEXPR_H
  12
  13 #include "llvm/MC/MCExpr.h"
  14
  15 namespace llvm {
  16
  17 class ARMMCExpr : public MCTargetExpr {
  18 public:
  19   enum VariantKind {
  20     VK_ARM_None,
  21     VK_ARM_HI16,  // The R_ARM_MOVT_ABS relocation (:upper16: in the .s file)
  22     VK_ARM_LO16   // The R_ARM_MOVW_ABS_NC relocation (:lower16: in the .s file)
  23   };
  24
  25 private:
  26   const VariantKind Kind;
  27   const MCExpr *Expr;
  28
  29   explicit ARMMCExpr(VariantKind _Kind, const MCExpr *_Expr)
  30     : Kind(_Kind), Expr(_Expr) {}
  31
  32 public:
  33   /// @name Construction
  34   /// @{
  35
  36   static const ARMMCExpr *Create(VariantKind Kind, const MCExpr *Expr,
  37                                       MCContext &Ctx);
  38
  39   static const ARMMCExpr *CreateUpper16(const MCExpr *Expr, MCContext &Ctx) {
  40     return Create(VK_ARM_HI16, Expr, Ctx);
  41   }
  42
  43   static const ARMMCExpr *CreateLower16(const MCExpr *Expr, MCContext &Ctx) {
  44     return Create(VK_ARM_LO16, Expr, Ctx);
  45   }
  46
  47   /// @}
  48   /// @name Accessors
  49   /// @{
  50
  51   /// getOpcode - Get the kind of this expression.
  52   VariantKind getKind() const { return Kind; }
  53
  54   /// getSubExpr - Get the child of this expression.
  55   const MCExpr *getSubExpr() const { return Expr; }
  56
  57   /// @}
  58
  59   void PrintImpl(raw_ostream &OS) const;
  60   bool EvaluateAsRelocatableImpl(MCValue &Res,
  61                                  const MCAsmLayout *Layout) const;
  62   void AddValueSymbols(MCAssembler *) const;
  63   const MCSection *FindAssociatedSection() const {
  64     return getSubExpr()->FindAssociatedSection();
  65   }
  66
  67   static bool classof(const MCExpr *E) {
  68     return E->getKind() == MCExpr::Target;
  69   }
  70
  71   static bool classof(const ARMMCExpr *) { return true; }
  72
  73 };
  74 } // end namespace llvm
  75
  76 #endif