C++ ObjectImage::begin_symbols方法代码示例

    virtual void NotifyObjectEmitted(const ObjectImage &obj)
    {
        uint64_t Addr;
        object::SymbolRef::Type SymbolType;

        #ifdef LLVM35
        for (const object::SymbolRef &sym_iter : obj.symbols()) {
            sym_iter.getType(SymbolType);
            if (SymbolType != object::SymbolRef::ST_Function) continue;
            sym_iter.getAddress(Addr);
            ObjectInfo tmp = {obj.getObjectFile(), sym_iter, obj.getData().size()};
            objectmap[Addr] = tmp;
        }
        #else
        error_code itererr; 
        object::symbol_iterator sym_iter = obj.begin_symbols();
        object::symbol_iterator sym_end = obj.end_symbols();
        for (; sym_iter != sym_end; sym_iter.increment(itererr)) {
            sym_iter->getType(SymbolType);
            if (SymbolType != object::SymbolRef::ST_Function) continue;
            sym_iter->getAddress(Addr);

            ObjectInfo tmp = {obj.getObjectFile(), *sym_iter};
            objectmap[Addr] = tmp;
        }
        #endif
    }

//.........这里部分代码省略.........
            objectmap[Addr] = tmp;
        }

#else // pre-LLVM37
        uint64_t Addr;
        uint64_t Size;
        object::SymbolRef::Type SymbolType;
        StringRef sName;
#ifdef LLVM36
        uint64_t SectionAddr = 0;
#else
        bool isText;
#ifdef _OS_WINDOWS_
        uint64_t SectionAddr = 0;
#endif
#endif

#if defined(LLVM35)
        for (const object::SymbolRef &sym_iter : obj.symbols()) {
            sym_iter.getType(SymbolType);
            if (SymbolType != object::SymbolRef::ST_Function) continue;
            sym_iter.getSize(Size);
            sym_iter.getAddress(Addr);
            sym_iter.getSection(Section);
            if (Section == EndSection) continue;
#if defined(LLVM36)
            if (!Section->isText()) continue;
            Section->getName(sName);
            SectionAddr = L.getSectionLoadAddress(sName);
            Addr += SectionAddr;
#else
            if (Section->isText(isText) || !isText) continue;
#endif
            sym_iter.getName(sName);
#ifdef _OS_DARWIN_
#   if !defined(LLVM36)
            Addr = ((MCJIT*)jl_ExecutionEngine)->getSymbolAddress(sName, true);
            if (!Addr && sName[0] == '_') {
                Addr = ((MCJIT*)jl_ExecutionEngine)->getSymbolAddress(sName.substr(1), true);
            }
            if (!Addr) continue;
#   endif
#elif defined(_OS_WINDOWS_)
            uint64_t SectionSize = 0;
#   if defined(LLVM36)
            SectionSize = Section->getSize();
#   else
            Section->getAddress(SectionAddr);
            Section->getSize(SectionSize);
#   endif
            if (SectionAddrCheck)
                assert(SectionAddrCheck == SectionAddr);
            else
                SectionAddrCheck = SectionAddr;
            create_PRUNTIME_FUNCTION(
                   (uint8_t*)(intptr_t)Addr, (size_t)Size, sName,
                   (uint8_t*)(intptr_t)SectionAddr, (size_t)SectionSize, UnwindData);
#endif
            StringMap<jl_lambda_info_t*>::iterator linfo_it = linfo_in_flight.find(sName);
            jl_lambda_info_t *linfo = NULL;
            if (linfo_it != linfo_in_flight.end()) {
                linfo = linfo_it->second;
                linfo_in_flight.erase(linfo_it);
            }
            const object::ObjectFile *objfile =
#ifdef LLVM36
                &obj;
#else
                obj.getObjectFile();
#endif
            ObjectInfo tmp = {objfile, (size_t)Size,
#ifdef LLVM37
                L.clone().release(),
#elif defined(LLVM36)
                (size_t)SectionAddr,
#endif
#ifdef _OS_DARWIN_
                strndup(sName.data(), sName.size()),
#endif
                linfo
            };
            objectmap[Addr] = tmp;
        }
#else //LLVM34
        error_code itererr;
        object::symbol_iterator sym_iter = obj.begin_symbols();
        object::symbol_iterator sym_end = obj.end_symbols();
        for (; sym_iter != sym_end; sym_iter.increment(itererr)) {
            sym_iter->getType(SymbolType);
            if (SymbolType != object::SymbolRef::ST_Function) continue;
            sym_iter->getAddress(Addr);
            sym_iter->getSize(Size);

            ObjectInfo tmp = {obj.getObjectFile(), (size_t)Size};
            objectmap[Addr] = tmp;
        }
#endif
#endif
        uv_rwlock_wrunlock(&threadsafe);
    }

// Compute an upper bound of the memory size that is required to load all
// sections
void RuntimeDyldImpl::computeTotalAllocSize(ObjectImage &Obj,
                                            uint64_t &CodeSize,
                                            uint64_t &DataSizeRO,
                                            uint64_t &DataSizeRW) {
  // Compute the size of all sections required for execution
  std::vector<uint64_t> CodeSectionSizes;
  std::vector<uint64_t> ROSectionSizes;
  std::vector<uint64_t> RWSectionSizes;
  uint64_t MaxAlignment = sizeof(void *);

  // Collect sizes of all sections to be loaded;
  // also determine the max alignment of all sections
  for (section_iterator SI = Obj.begin_sections(), SE = Obj.end_sections();
       SI != SE; ++SI) {
    const SectionRef &Section = *SI;

    bool IsRequired = Section.isRequiredForExecution();

    // Consider only the sections that are required to be loaded for execution
    if (IsRequired) {
      StringRef Name;
      uint64_t DataSize = Section.getSize();
      uint64_t Alignment64 = Section.getAlignment();
      bool IsCode = Section.isText();
      bool IsReadOnly = Section.isReadOnlyData();
      Check(Section.getName(Name));
      unsigned Alignment = (unsigned)Alignment64 & 0xffffffffL;

      uint64_t StubBufSize = computeSectionStubBufSize(Obj, Section);
      uint64_t SectionSize = DataSize + StubBufSize;

      // The .eh_frame section (at least on Linux) needs an extra four bytes
      // padded
      // with zeroes added at the end.  For MachO objects, this section has a
      // slightly different name, so this won't have any effect for MachO
      // objects.
      if (Name == ".eh_frame")
        SectionSize += 4;

      if (SectionSize > 0) {
        // save the total size of the section
        if (IsCode) {
          CodeSectionSizes.push_back(SectionSize);
        } else if (IsReadOnly) {
          ROSectionSizes.push_back(SectionSize);
        } else {
          RWSectionSizes.push_back(SectionSize);
        }
        // update the max alignment
        if (Alignment > MaxAlignment) {
          MaxAlignment = Alignment;
        }
      }
    }
  }

  // Compute the size of all common symbols
  uint64_t CommonSize = 0;
  for (symbol_iterator I = Obj.begin_symbols(), E = Obj.end_symbols(); I != E;
       ++I) {
    uint32_t Flags = I->getFlags();
    if (Flags & SymbolRef::SF_Common) {
      // Add the common symbols to a list.  We'll allocate them all below.
      uint64_t Size = 0;
      Check(I->getSize(Size));
      CommonSize += Size;
    }
  }
  if (CommonSize != 0) {
    RWSectionSizes.push_back(CommonSize);
  }

  // Compute the required allocation space for each different type of sections
  // (code, read-only data, read-write data) assuming that all sections are
  // allocated with the max alignment. Note that we cannot compute with the
  // individual alignments of the sections, because then the required size
  // depends on the order, in which the sections are allocated.
  CodeSize = computeAllocationSizeForSections(CodeSectionSizes, MaxAlignment);
  DataSizeRO = computeAllocationSizeForSections(ROSectionSizes, MaxAlignment);
  DataSizeRW = computeAllocationSizeForSections(RWSectionSizes, MaxAlignment);
}

//.........这里部分代码省略.........
        for (const object::SymbolRef &sym_iter : obj.symbols()) {
#           ifdef LLVM37
            SymbolType = sym_iter.getType();
#           else
            sym_iter.getType(SymbolType);
#           endif
            if (SymbolType != object::SymbolRef::ST_Function) continue;
#           ifdef LLVM37
            Addr = sym_iter.getAddress().get();
#           else
            sym_iter.getAddress(Addr);
#           endif
            sym_iter.getSection(Section);
            if (Section == EndSection) continue;
#if defined(LLVM36)
            if (!Section->isText()) continue;
            Section->getName(sName);
            SectionAddr = L.getSectionLoadAddress(sName);
            Addr += SectionAddr;
#else
            if (Section->isText(isText) || !isText) continue;
#endif
#if defined(LLVM36)
            SectionSize = Section->getSize();
#else
            Section->getAddress(SectionAddr);
            Section->getSize(SectionSize);
#endif
#ifdef _OS_DARWIN_
#   if defined(LLVM37)
            Size = Section->getSize();
            sName = sym_iter.getName().get();
#   else
            sym_iter.getName(sName);
#   endif
#   if defined(LLVM36)
            if (sName[0] == '_') {
                sName = sName.substr(1);
            }
#   else
            Addr = ((MCJIT*)jl_ExecutionEngine)->getSymbolAddress(sName, true);
            if (!Addr && sName[0] == '_') {
                sName = sName.substr(1);
                Addr = ((MCJIT*)jl_ExecutionEngine)->getSymbolAddress(sName, true);
            }
            if (!Addr) continue;
#   endif
#elif defined(_OS_WINDOWS_)
#   if defined(LLVM37)
            assert(obj.isELF());
            Size = ((llvm::object::ELFSymbolRef)sym_iter).getSize();
            sName = sym_iter.getName().get();
#   else
            sym_iter.getSize(Size);
            sym_iter.getName(sName);
#   endif
#   ifdef _CPU_X86_
            if (sName[0] == '_') sName = sName.substr(1);
#   endif
            if (SectionAddrCheck)
                assert(SectionAddrCheck == SectionAddr);
            else
                SectionAddrCheck = SectionAddr;
            create_PRUNTIME_FUNCTION(
                   (uint8_t*)(intptr_t)Addr, (size_t)Size, sName,
                   (uint8_t*)(intptr_t)SectionAddr, (size_t)SectionSize, UnwindData);
#endif
            const object::ObjectFile *objfile =
#ifdef LLVM36
                &obj;
#else
                obj.getObjectFile();
#endif
            ObjectInfo tmp = {objfile, SectionSize
#ifdef LLVM37
                ,L.clone().release()
#elif defined(LLVM36)
                ,(size_t)SectionAddr
#endif
#ifdef _OS_DARWIN_
                ,strndup(sName.data(), sName.size())
#endif
            };
            objectmap[Addr] = tmp;
        }
#else //LLVM34
        error_code itererr;
        object::symbol_iterator sym_iter = obj.begin_symbols();
        object::symbol_iterator sym_end = obj.end_symbols();
        for (; sym_iter != sym_end; sym_iter.increment(itererr)) {
            sym_iter->getType(SymbolType);
            if (SymbolType != object::SymbolRef::ST_Function) continue;
            sym_iter->getAddress(Addr);
            sym_iter->getSize(Size);

            ObjectInfo tmp = {obj.getObjectFile(), (size_t)Size};
            objectmap[Addr] = tmp;
        }
#endif
    }