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, 54 const MCExpr *Subsection = nullptr) override; 55 56 /// Overriding these functions allows us to dismiss all labels that are 57 /// candidates for marking as microMIPS when .word/.long/.4byte etc 58 /// directives are emitted. 59 void EmitValueImpl(const MCExpr *Value, unsigned Size, SMLoc Loc) override; 60 void EmitIntValue(uint64_t Value, unsigned Size) override; 61 62 // Overriding these functions allows us to avoid recording of these labels 63 // in EmitLabel and later marking them as microMIPS. 64 void EmitCFIStartProcImpl(MCDwarfFrameInfo &Frame) override; 65 void EmitCFIEndProcImpl(MCDwarfFrameInfo &Frame) override; 66 MCSymbol *EmitCFILabel() override; 67 68 /// Emits all the option records stored up until the point it's called. 69 void EmitMipsOptionRecords(); 70 71 /// Mark labels as microMIPS, if necessary for the subtarget. 72 void createPendingLabelRelocs(); 73}; 74 75MCELFStreamer *createMipsELFStreamer(MCContext &Context, 76 std::unique_ptr<MCAsmBackend> MAB, 77 std::unique_ptr<MCObjectWriter> OW, 78 std::unique_ptr<MCCodeEmitter> Emitter, 79 bool RelaxAll); 80} // end namespace llvm 81 82#endif // LLVM_LIB_TARGET_MIPS_MCTARGETDESC_MIPSELFSTREAMER_H 83