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
77