1//===- MipsELFStreamer.h - ELF Object Output --------------------*- 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// This is a custom MCELFStreamer which allows us to insert some hooks before
10// emitting data into an actual object file.
11//
12//===----------------------------------------------------------------------===//
13
14#ifndef LLVM_LIB_TARGET_MIPS_MCTARGETDESC_MIPSELFSTREAMER_H
15#define LLVM_LIB_TARGET_MIPS_MCTARGETDESC_MIPSELFSTREAMER_H
16
17#include "MipsOptionRecord.h"
18#include "llvm/ADT/SmallVector.h"
19#include "llvm/MC/MCELFStreamer.h"
20#include <memory>
21
22namespace llvm {
23
24class MCAsmBackend;
25class MCCodeEmitter;
26class MCContext;
27class MCSubtargetInfo;
28struct MCDwarfFrameInfo;
29
30class MipsELFStreamer : public MCELFStreamer {
31 SmallVector<std::unique_ptr<MipsOptionRecord>, 8> MipsOptionRecords;
32 MipsRegInfoRecord *RegInfoRecord;
33 SmallVector<MCSymbol*, 4> Labels;
34
35public:
36 MipsELFStreamer(MCContext &Context, std::unique_ptr<MCAsmBackend> MAB,
37 std::unique_ptr<MCObjectWriter> OW,
38 std::unique_ptr<MCCodeEmitter> Emitter);
39
40 /// Overriding this function allows us to add arbitrary behaviour before the
41 /// \p Inst is actually emitted. For example, we can inspect the operands and
42 /// gather sufficient information that allows us to reason about the register
43 /// usage for the translation unit.
44 void emitInstruction(const MCInst &Inst, const MCSubtargetInfo &STI) override;
45
46 /// Overriding this function allows us to record all labels that should be
47 /// marked as microMIPS. Based on this data marking is done in
48 /// EmitInstruction.
49 void emitLabel(MCSymbol *Symbol, SMLoc Loc = SMLoc()) override;
50
51 /// Overriding this function allows us to dismiss all labels that are
52 /// candidates for marking as microMIPS when .section directive is processed.
53 void switchSection(MCSection *Section, uint32_t Subsection = 0) override;
54
55 /// Overriding these functions allows us to dismiss all labels that are
56 /// candidates for marking as microMIPS when .word/.long/.4byte etc
57 /// directives are emitted.
58 void emitValueImpl(const MCExpr *Value, unsigned Size, SMLoc Loc) override;
59 void emitIntValue(uint64_t Value, unsigned Size) override;
60
61 // Overriding these functions allows us to avoid recording of these labels
62 // in EmitLabel and later marking them as microMIPS.
63 void emitCFIStartProcImpl(MCDwarfFrameInfo &Frame) override;
64 void emitCFIEndProcImpl(MCDwarfFrameInfo &Frame) override;
65 MCSymbol *emitCFILabel() override;
66
67 /// Emits all the option records stored up until the point it's called.
68 void EmitMipsOptionRecords();
69
70 /// Mark labels as microMIPS, if necessary for the subtarget.
71 void createPendingLabelRelocs();
72};
73
74MCELFStreamer *createMipsELFStreamer(MCContext &Context,
75 std::unique_ptr<MCAsmBackend> MAB,
76 std::unique_ptr<MCObjectWriter> OW,
77 std::unique_ptr<MCCodeEmitter> Emitter);
78} // end namespace llvm
79
80#endif // LLVM_LIB_TARGET_MIPS_MCTARGETDESC_MIPSELFSTREAMER_H
81