1 //===-- AVRMCExpr.h - AVR 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_AVR_MCEXPR_H
10 #define LLVM_AVR_MCEXPR_H
11 
12 #include "llvm/MC/MCExpr.h"
13 
14 #include "MCTargetDesc/AVRFixupKinds.h"
15 
16 namespace llvm {
17 
18 /// A expression in AVR machine code.
19 class AVRMCExpr : public MCTargetExpr {
20 public:
21   /// Specifies the type of an expression.
22   enum VariantKind {
23     VK_AVR_None = 0,
24 
25     VK_AVR_HI8,  ///< Corresponds to `hi8()`.
26     VK_AVR_LO8,  ///< Corresponds to `lo8()`.
27     VK_AVR_HH8,  ///< Corresponds to `hlo8() and hh8()`.
28     VK_AVR_HHI8, ///< Corresponds to `hhi8()`.
29 
30     VK_AVR_PM,     ///< Corresponds to `pm()`, reference to program memory.
31     VK_AVR_PM_LO8, ///< Corresponds to `pm_lo8()`.
32     VK_AVR_PM_HI8, ///< Corresponds to `pm_hi8()`.
33     VK_AVR_PM_HH8, ///< Corresponds to `pm_hh8()`.
34 
35     VK_AVR_LO8_GS, ///< Corresponds to `lo8(gs())`.
36     VK_AVR_HI8_GS, ///< Corresponds to `hi8(gs())`.
37     VK_AVR_GS,     ///< Corresponds to `gs()`.
38   };
39 
40 public:
41   /// Creates an AVR machine code expression.
42   static const AVRMCExpr *create(VariantKind Kind, const MCExpr *Expr,
43                                  bool isNegated, MCContext &Ctx);
44 
45   /// Gets the type of the expression.
46   VariantKind getKind() const { return Kind; }
47   /// Gets the name of the expression.
48   const char *getName() const;
49   const MCExpr *getSubExpr() const { return SubExpr; }
50   /// Gets the fixup which corresponds to the expression.
51   AVR::Fixups getFixupKind() const;
52   /// Evaluates the fixup as a constant value.
53   bool evaluateAsConstant(int64_t &Result) const;
54 
55   bool isNegated() const { return Negated; }
56   void setNegated(bool negated = true) { Negated = negated; }
57 
58   void printImpl(raw_ostream &OS, const MCAsmInfo *MAI) const override;
59   bool evaluateAsRelocatableImpl(MCValue &Res, const MCAsmLayout *Layout,
60                                  const MCFixup *Fixup) const override;
61 
62   void visitUsedExpr(MCStreamer &streamer) const override;
63 
64   MCFragment *findAssociatedFragment() const override {
65     return getSubExpr()->findAssociatedFragment();
66   }
67 
68   void fixELFSymbolsInTLSFixups(MCAssembler &Asm) const override {}
69 
70   static bool classof(const MCExpr *E) {
71     return E->getKind() == MCExpr::Target;
72   }
73 
74 public:
75   static VariantKind getKindByName(StringRef Name);
76 
77 private:
78   int64_t evaluateAsInt64(int64_t Value) const;
79 
80   const VariantKind Kind;
81   const MCExpr *SubExpr;
82   bool Negated;
83 
84 private:
85   explicit AVRMCExpr(VariantKind Kind, const MCExpr *Expr, bool Negated)
86       : Kind(Kind), SubExpr(Expr), Negated(Negated) {}
87   ~AVRMCExpr() = default;
88 };
89 
90 } // end namespace llvm
91 
92 #endif // LLVM_AVR_MCEXPR_H
93