1 //===- MCWasmStreamer.h - MCStreamer Wasm Object File Interface -*- 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_MC_MCWASMSTREAMER_H
10 #define LLVM_MC_MCWASMSTREAMER_H
11 
12 #include "MCAsmBackend.h"
13 #include "MCCodeEmitter.h"
14 #include "llvm/MC/MCDirectives.h"
15 #include "llvm/MC/MCObjectStreamer.h"
16 #include "llvm/MC/MCObjectWriter.h"
17 #include "llvm/Support/DataTypes.h"
18 
19 namespace llvm {
20 class MCExpr;
21 class MCInst;
22 
23 class MCWasmStreamer : public MCObjectStreamer {
24 public:
25   MCWasmStreamer(MCContext &Context, std::unique_ptr<MCAsmBackend> TAB,
26                  std::unique_ptr<MCObjectWriter> OW,
27                  std::unique_ptr<MCCodeEmitter> Emitter)
28       : MCObjectStreamer(Context, std::move(TAB), std::move(OW),
29                          std::move(Emitter)),
30         SeenIdent(false) {}
31 
32   ~MCWasmStreamer() override;
33 
34   /// state management
35   void reset() override {
36     SeenIdent = false;
37     MCObjectStreamer::reset();
38   }
39 
40   /// \name MCStreamer Interface
41   /// @{
42 
43   void changeSection(MCSection *Section, const MCExpr *Subsection) override;
44   void emitLabel(MCSymbol *Symbol, SMLoc Loc = SMLoc()) override;
45   void emitLabelAtPos(MCSymbol *Symbol, SMLoc Loc, MCFragment *F,
46                       uint64_t Offset) override;
47   void emitAssemblerFlag(MCAssemblerFlag Flag) override;
48   void emitThumbFunc(MCSymbol *Func) override;
49   void emitWeakReference(MCSymbol *Alias, const MCSymbol *Symbol) override;
50   bool emitSymbolAttribute(MCSymbol *Symbol, MCSymbolAttr Attribute) override;
51   void emitSymbolDesc(MCSymbol *Symbol, unsigned DescValue) override;
52   void emitCommonSymbol(MCSymbol *Symbol, uint64_t Size,
53                         unsigned ByteAlignment) override;
54 
55   void emitELFSize(MCSymbol *Symbol, const MCExpr *Value) override;
56 
57   void emitLocalCommonSymbol(MCSymbol *Symbol, uint64_t Size,
58                              unsigned ByteAlignment) override;
59 
60   void emitZerofill(MCSection *Section, MCSymbol *Symbol = nullptr,
61                     uint64_t Size = 0, unsigned ByteAlignment = 0,
62                     SMLoc Loc = SMLoc()) override;
63   void emitTBSSSymbol(MCSection *Section, MCSymbol *Symbol, uint64_t Size,
64                       unsigned ByteAlignment = 0) override;
65 
66   void emitIdent(StringRef IdentString) override;
67 
68   void finishImpl() override;
69 
70 private:
71   void emitInstToFragment(const MCInst &Inst, const MCSubtargetInfo &) override;
72   void emitInstToData(const MCInst &Inst, const MCSubtargetInfo &) override;
73 
74   void fixSymbolsInTLSFixups(const MCExpr *expr);
75 
76   /// Merge the content of the fragment \p EF into the fragment \p DF.
77   void mergeFragment(MCDataFragment *, MCDataFragment *);
78 
79   bool SeenIdent;
80 };
81 
82 } // end namespace llvm
83 
84 #endif
85