MipsAsmBackend.h revision dce4a407a24b04eebc6a376f8e62b41aaa7b071f 
1//===-- MipsAsmBackend.h - Mips Asm Backend  ------------------------------===//
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// This file defines the MipsAsmBackend class.
11//
12//===----------------------------------------------------------------------===//
13//
14
15#ifndef MIPSASMBACKEND_H
16#define MIPSASMBACKEND_H
17
18#include "MCTargetDesc/MipsFixupKinds.h"
19#include "llvm/MC/MCAsmBackend.h"
20#include "llvm/ADT/Triple.h"
21
22namespace llvm {
23
24class MCAssembler;
25struct MCFixupKindInfo;
26class Target;
27class MCObjectWriter;
28
29class MipsAsmBackend : public MCAsmBackend {
30  Triple::OSType OSType;
31  bool IsLittle; // Big or little endian
32  bool Is64Bit;  // 32 or 64 bit words
33
34public:
35  MipsAsmBackend(const Target &T, Triple::OSType _OSType, bool _isLittle,
36                 bool _is64Bit)
37      : MCAsmBackend(), OSType(_OSType), IsLittle(_isLittle),
38        Is64Bit(_is64Bit) {}
39
40  MCObjectWriter *createObjectWriter(raw_ostream &OS) const override;
41
42  void applyFixup(const MCFixup &Fixup, char *Data, unsigned DataSize,
43                  uint64_t Value, bool IsPCRel) const override;
44
45  const MCFixupKindInfo &getFixupKindInfo(MCFixupKind Kind) const override;
46
47  unsigned getNumFixupKinds() const override {
48    return Mips::NumTargetFixupKinds;
49  }
50
51  /// @name Target Relaxation Interfaces
52  /// @{
53
54  /// MayNeedRelaxation - Check whether the given instruction may need
55  /// relaxation.
56  ///
57  /// \param Inst - The instruction to test.
58  bool mayNeedRelaxation(const MCInst &Inst) const override {
59    return false;
60  }
61
62  /// fixupNeedsRelaxation - Target specific predicate for whether a given
63  /// fixup requires the associated instruction to be relaxed.
64   bool fixupNeedsRelaxation(const MCFixup &Fixup, uint64_t Value,
65                             const MCRelaxableFragment *DF,
66                             const MCAsmLayout &Layout) const override {
67    // FIXME.
68    assert(0 && "RelaxInstruction() unimplemented");
69    return false;
70  }
71
72  /// RelaxInstruction - Relax the instruction in the given fragment
73  /// to the next wider instruction.
74  ///
75  /// \param Inst - The instruction to relax, which may be the same
76  /// as the output.
77  /// \param [out] Res On return, the relaxed instruction.
78  void relaxInstruction(const MCInst &Inst, MCInst &Res) const override {}
79
80  /// @}
81
82  bool writeNopData(uint64_t Count, MCObjectWriter *OW) const override;
83
84  void processFixupValue(const MCAssembler &Asm, const MCAsmLayout &Layout,
85                         const MCFixup &Fixup, const MCFragment *DF,
86                         const MCValue &Target, uint64_t &Value,
87                         bool &IsResolved) override;
88
89}; // class MipsAsmBackend
90
91} // namespace
92
93#endif
94