1 //===-- ARMMCExpr.h - ARM specific MC expression classes --------*- 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_LIB_TARGET_ARM_MCTARGETDESC_ARMMCEXPR_H
10 #define LLVM_LIB_TARGET_ARM_MCTARGETDESC_ARMMCEXPR_H
11 
12 #include "llvm/MC/MCExpr.h"
13 
14 namespace llvm {
15 
16 class ARMMCExpr : public MCTargetExpr {
17 public:
18   enum VariantKind {
19     VK_ARM_None,
20     VK_ARM_HI16, // The R_ARM_MOVT_ABS relocation (:upper16: in the .s file)
21     VK_ARM_LO16, // The R_ARM_MOVW_ABS_NC relocation (:lower16: in the .s file)
22 
23     VK_ARM_HI_8_15, // The R_ARM_THM_ALU_ABS_G3    relocation (:upper8_15: in
24                     // the .s file)
25     VK_ARM_HI_0_7,  // The R_ARM_THM_ALU_ABS_G2_NC relocation (:upper0_8: in the
26                     // .s file)
27     VK_ARM_LO_8_15, // The R_ARM_THM_ALU_ABS_G1_NC relocation (:lower8_15: in
28                     // the .s file)
29     VK_ARM_LO_0_7,  // The R_ARM_THM_ALU_ABS_G0_NC relocation (:lower0_7: in the
30                     // .s file)
31   };
32 
33 private:
34   const VariantKind Kind;
35   const MCExpr *Expr;
36 
37   explicit ARMMCExpr(VariantKind Kind, const MCExpr *Expr)
38       : Kind(Kind), Expr(Expr) {}
39 
40 public:
41   /// @name Construction
42   /// @{
43 
44   static const ARMMCExpr *create(VariantKind Kind, const MCExpr *Expr,
45                                       MCContext &Ctx);
46 
47   static const ARMMCExpr *createUpper16(const MCExpr *Expr, MCContext &Ctx) {
48     return create(VK_ARM_HI16, Expr, Ctx);
49   }
50 
51   static const ARMMCExpr *createLower16(const MCExpr *Expr, MCContext &Ctx) {
52     return create(VK_ARM_LO16, Expr, Ctx);
53   }
54 
55   static const ARMMCExpr *createUpper8_15(const MCExpr *Expr, MCContext &Ctx) {
56     return create(VK_ARM_HI_8_15, Expr, Ctx);
57   }
58 
59   static const ARMMCExpr *createUpper0_7(const MCExpr *Expr, MCContext &Ctx) {
60     return create(VK_ARM_HI_0_7, Expr, Ctx);
61   }
62 
63   static const ARMMCExpr *createLower8_15(const MCExpr *Expr, MCContext &Ctx) {
64     return create(VK_ARM_LO_8_15, Expr, Ctx);
65   }
66 
67   static const ARMMCExpr *createLower0_7(const MCExpr *Expr, MCContext &Ctx) {
68     return create(VK_ARM_LO_0_7, Expr, Ctx);
69   }
70 
71   /// @}
72   /// @name Accessors
73   /// @{
74 
75   /// getOpcode - Get the kind of this expression.
76   VariantKind getKind() const { return Kind; }
77 
78   /// getSubExpr - Get the child of this expression.
79   const MCExpr *getSubExpr() const { return Expr; }
80 
81   /// @}
82 
83   void printImpl(raw_ostream &OS, const MCAsmInfo *MAI) const override;
84   bool evaluateAsRelocatableImpl(MCValue &Res,
85                                  const MCAsmLayout *Layout,
86                                  const MCFixup *Fixup) const override {
87     return false;
88   }
89   void visitUsedExpr(MCStreamer &Streamer) const override;
90   MCFragment *findAssociatedFragment() const override {
91     return getSubExpr()->findAssociatedFragment();
92   }
93 
94   // There are no TLS ARMMCExprs at the moment.
95   void fixELFSymbolsInTLSFixups(MCAssembler &Asm) const override {}
96 
97   static bool classof(const MCExpr *E) {
98     return E->getKind() == MCExpr::Target;
99   }
100 };
101 } // end namespace llvm
102 
103 #endif
104