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 LLVM_LIB_TARGET_MIPS_MCTARGETDESC_MIPSASMBACKEND_H
16 #define LLVM_LIB_TARGET_MIPS_MCTARGETDESC_MIPSASMBACKEND_H
17 
18 #include "MCTargetDesc/MipsFixupKinds.h"
19 #include "llvm/ADT/Triple.h"
20 #include "llvm/MC/MCAsmBackend.h"
21 
22 namespace llvm {
23 
24 class MCAssembler;
25 struct MCFixupKindInfo;
26 class MCObjectWriter;
27 class MCRegisterInfo;
28 class MCSymbolELF;
29 class Target;
30 
31 class MipsAsmBackend : public MCAsmBackend {
32   Triple TheTriple;
33   bool IsN32;
34 
35 public:
MipsAsmBackend(const Target & T,const MCRegisterInfo & MRI,const Triple & TT,StringRef CPU,bool N32)36   MipsAsmBackend(const Target &T, const MCRegisterInfo &MRI, const Triple &TT,
37                  StringRef CPU, bool N32)
38       : MCAsmBackend(TT.isLittleEndian() ? support::little : support::big),
39         TheTriple(TT), IsN32(N32) {}
40 
41   std::unique_ptr<MCObjectTargetWriter>
42   createObjectTargetWriter() const override;
43 
44   void applyFixup(const MCAssembler &Asm, const MCFixup &Fixup,
45                   const MCValue &Target, MutableArrayRef<char> Data,
46                   uint64_t Value, bool IsResolved,
47                   const MCSubtargetInfo *STI) const override;
48 
49   Optional<MCFixupKind> getFixupKind(StringRef Name) const override;
50   const MCFixupKindInfo &getFixupKindInfo(MCFixupKind Kind) const override;
51 
getNumFixupKinds()52   unsigned getNumFixupKinds() const override {
53     return Mips::NumTargetFixupKinds;
54   }
55 
56   /// @name Target Relaxation Interfaces
57   /// @{
58 
59   /// MayNeedRelaxation - Check whether the given instruction may need
60   /// relaxation.
61   ///
62   /// \param Inst - The instruction to test.
mayNeedRelaxation(const MCInst & Inst,const MCSubtargetInfo & STI)63   bool mayNeedRelaxation(const MCInst &Inst,
64                          const MCSubtargetInfo &STI) const override {
65     return false;
66   }
67 
68   /// fixupNeedsRelaxation - Target specific predicate for whether a given
69   /// fixup requires the associated instruction to be relaxed.
fixupNeedsRelaxation(const MCFixup & Fixup,uint64_t Value,const MCRelaxableFragment * DF,const MCAsmLayout & Layout)70    bool fixupNeedsRelaxation(const MCFixup &Fixup, uint64_t Value,
71                              const MCRelaxableFragment *DF,
72                              const MCAsmLayout &Layout) const override {
73     // FIXME.
74     llvm_unreachable("RelaxInstruction() unimplemented");
75     return false;
76   }
77 
78   /// RelaxInstruction - Relax the instruction in the given fragment
79   /// to the next wider instruction.
80   ///
81   /// \param Inst - The instruction to relax, which may be the same
82   /// as the output.
83   /// \param [out] Res On return, the relaxed instruction.
relaxInstruction(const MCInst & Inst,const MCSubtargetInfo & STI,MCInst & Res)84   void relaxInstruction(const MCInst &Inst, const MCSubtargetInfo &STI,
85                         MCInst &Res) const override {}
86 
87   /// @}
88 
89   bool writeNopData(raw_ostream &OS, uint64_t Count) const override;
90 
91   bool shouldForceRelocation(const MCAssembler &Asm, const MCFixup &Fixup,
92                              const MCValue &Target) override;
93 
94   bool isMicroMips(const MCSymbol *Sym) const override;
95 }; // class MipsAsmBackend
96 
97 } // namespace
98 
99 #endif
100