text: //===-- CSKYELFStreamer.h - CSKY ELF Target Streamer -----------*- C++ -*--===//
  //
  // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
  // See https://llvm.org/LICENSE.txt for license information.
  // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
  //
  //===----------------------------------------------------------------------===//
  
  #ifndef LLVM_LIB_TARGET_CSKY_CSKYELFSTREAMER_H
  #define LLVM_LIB_TARGET_CSKY_CSKYELFSTREAMER_H
  
  #include "CSKYTargetStreamer.h"
  #include "llvm/MC/MCCodeEmitter.h"
  #include "llvm/MC/MCELFStreamer.h"
  #include "llvm/MC/MCObjectWriter.h"
  
  namespace llvm {
  
  class CSKYTargetELFStreamer : public CSKYTargetStreamer {
  private:
    enum class AttributeType { Hidden, Numeric, Text, NumericAndText };
  
    struct AttributeItem {
      AttributeType Type;
      unsigned Tag;
      unsigned IntValue;
      std::string StringValue;
    };
  
    StringRef CurrentVendor;
    SmallVector<AttributeItem, 64> Contents;
  
    MCSection *AttributeSection = nullptr;
  
    AttributeItem *getAttributeItem(unsigned Attribute) {
      for (size_t i = 0; i < Contents.size(); ++i)
        if (Contents[i].Tag == Attribute)
          return &Contents[i];
      return nullptr;
    }
  
    void setAttributeItem(unsigned Attribute, unsigned Value,
                          bool OverwriteExisting) {
      // Look for existing attribute item.
      if (AttributeItem *Item = getAttributeItem(Attribute)) {
        if (!OverwriteExisting)
          return;
        Item->Type = AttributeType::Numeric;
        Item->IntValue = Value;
        return;
      }
  
      // Create new attribute item.
      Contents.push_back({AttributeType::Numeric, Attribute, Value, ""});
    }
  
    void setAttributeItem(unsigned Attribute, StringRef Value,
                          bool OverwriteExisting) {
      // Look for existing attribute item.
      if (AttributeItem *Item = getAttributeItem(Attribute)) {
        if (!OverwriteExisting)
          return;
        Item->Type = AttributeType::Text;
        Item->StringValue = std::string(Value);
        return;
      }
  
      // Create new attribute item.
      Contents.push_back({AttributeType::Text, Attribute, 0, std::string(Value)});
    }
  
    void setAttributeItems(unsigned Attribute, unsigned IntValue,
                           StringRef StringValue, bool OverwriteExisting) {
      // Look for existing attribute item.
      if (AttributeItem *Item = getAttributeItem(Attribute)) {
        if (!OverwriteExisting)
          return;
        Item->Type = AttributeType::NumericAndText;
        Item->IntValue = IntValue;
        Item->StringValue = std::string(StringValue);
        return;
      }
  
      // Create new attribute item.
      Contents.push_back({AttributeType::NumericAndText, Attribute, IntValue,
                          std::string(StringValue)});
    }
  
    void emitAttribute(unsigned Attribute, unsigned Value) override;
    void emitTextAttribute(unsigned Attribute, StringRef String) override;
    void finishAttributeSection() override;
    size_t calculateContentSize() const;
  
    void emitTargetAttributes(const MCSubtargetInfo &STI) override;
  
  public:
    MCELFStreamer &getStreamer();
    CSKYTargetELFStreamer(MCStreamer &S, const MCSubtargetInfo &STI);
  };
  
  class CSKYELFStreamer : public MCELFStreamer {
    int64_t MappingSymbolCounter = 0;
  
    void EmitMappingSymbol(StringRef Name);
  
  public:
    friend class CSKYTargetELFStreamer;
  
    enum ElfMappingSymbol { EMS_None, EMS_Text, EMS_Data };
  
    ElfMappingSymbol State;
  
    CSKYELFStreamer(MCContext &Context, std::unique_ptr<MCAsmBackend> TAB,
                    std::unique_ptr<MCObjectWriter> OW,
                    std::unique_ptr<MCCodeEmitter> Emitter)
        : MCELFStreamer(Context, std::move(TAB), std::move(OW),
                        std::move(Emitter)),
          State(EMS_None) {}
  
    ~CSKYELFStreamer() override = default;
  
    void emitFill(const MCExpr &NumBytes, uint64_t FillValue,
                  SMLoc Loc) override {
      EmitMappingSymbol("$d");
      MCObjectStreamer::emitFill(NumBytes, FillValue, Loc);
    }
    void emitBytes(StringRef Data) override {
      EmitMappingSymbol("$d");
      MCELFStreamer::emitBytes(Data);
    }
    void emitInstruction(const MCInst &Inst,
                         const MCSubtargetInfo &STI) override {
      EmitMappingSymbol("$t");
      MCELFStreamer::emitInstruction(Inst, STI);
    }
    void emitValueImpl(const MCExpr *Value, unsigned Size, SMLoc Loc) override {
      EmitMappingSymbol("$d");
      MCELFStreamer::emitValueImpl(Value, Size, Loc);
    }
    void reset() override {
      MappingSymbolCounter = 0;
      State = EMS_None;
      MCELFStreamer::reset();
    }
  };
  
  } // namespace llvm
  #endif
  