#ifndef LLVM_MC_MCMACHOBJECTWRITER_H
#define LLVM_MC_MCMACHOBJECTWRITER_H
+#include "llvm/ADT/DenseMap.h"
+#include "llvm/ADT/SmallString.h"
+#include "llvm/MC/MCExpr.h"
#include "llvm/MC/MCObjectWriter.h"
#include "llvm/Support/DataTypes.h"
+#include "llvm/Support/MachO.h"
+#include <vector>
namespace llvm {
+class MCSectionData;
+class MachObjectWriter;
+
class MCMachObjectTargetWriter {
const unsigned Is64Bit : 1;
const uint32_t CPUType;
public:
virtual ~MCMachObjectTargetWriter();
+ /// @name Lifetime Management
+ /// @{
+
+ virtual void reset() {};
+
+ /// @}
+
/// @name Accessors
/// @{
}
/// @}
+
+ /// @name API
+ /// @{
+
+ virtual void RecordRelocation(MachObjectWriter *Writer,
+ const MCAssembler &Asm,
+ const MCAsmLayout &Layout,
+ const MCFragment *Fragment,
+ const MCFixup &Fixup,
+ MCValue Target,
+ uint64_t &FixedValue) = 0;
+
+ /// @}
+};
+
+class MachObjectWriter : public MCObjectWriter {
+ /// MachSymbolData - Helper struct for containing some precomputed information
+ /// on symbols.
+ struct MachSymbolData {
+ MCSymbolData *SymbolData;
+ uint64_t StringIndex;
+ uint8_t SectionIndex;
+
+ // Support lexicographic sorting.
+ bool operator<(const MachSymbolData &RHS) const;
+ };
+
+ /// The target specific Mach-O writer instance.
+ std::unique_ptr<MCMachObjectTargetWriter> TargetObjectWriter;
+
+ /// @name Relocation Data
+ /// @{
+
+ llvm::DenseMap<const MCSectionData*,
+ std::vector<MachO::any_relocation_info> > Relocations;
+ llvm::DenseMap<const MCSectionData*, unsigned> IndirectSymBase;
+
+ /// @}
+ /// @name Symbol Table Data
+ /// @{
+
+ SmallString<256> StringTable;
+ std::vector<MachSymbolData> LocalSymbolData;
+ std::vector<MachSymbolData> ExternalSymbolData;
+ std::vector<MachSymbolData> UndefinedSymbolData;
+
+ /// @}
+
+ MachSymbolData *findSymbolData(const MCSymbol &Sym);
+
+public:
+ MachObjectWriter(MCMachObjectTargetWriter *MOTW, raw_ostream &_OS,
+ bool _IsLittleEndian)
+ : MCObjectWriter(_OS, _IsLittleEndian), TargetObjectWriter(MOTW) {
+ }
+
+ /// @name Lifetime management Methods
+ /// @{
+
+ void reset() override;
+
+ /// @}
+
+ /// @name Utility Methods
+ /// @{
+
+ bool isFixupKindPCRel(const MCAssembler &Asm, unsigned Kind);
+
+ SectionAddrMap SectionAddress;
+
+ SectionAddrMap &getSectionAddressMap() { return SectionAddress; }
+
+ uint64_t getSectionAddress(const MCSectionData* SD) const {
+ return SectionAddress.lookup(SD);
+ }
+ uint64_t getSymbolAddress(const MCSymbolData* SD,
+ const MCAsmLayout &Layout) const;
+
+ uint64_t getFragmentAddress(const MCFragment *Fragment,
+ const MCAsmLayout &Layout) const;
+
+ uint64_t getPaddingSize(const MCSectionData *SD,
+ const MCAsmLayout &Layout) const;
+
+ bool doesSymbolRequireExternRelocation(const MCSymbolData *SD);
+
+ /// @}
+
+ /// @name Target Writer Proxy Accessors
+ /// @{
+
+ bool is64Bit() const { return TargetObjectWriter->is64Bit(); }
+ bool isX86_64() const {
+ uint32_t CPUType = TargetObjectWriter->getCPUType();
+ return CPUType == MachO::CPU_TYPE_X86_64;
+ }
+
+ /// @}
+
+ void WriteHeader(unsigned NumLoadCommands, unsigned LoadCommandsSize,
+ bool SubsectionsViaSymbols);
+
+ /// WriteSegmentLoadCommand - Write a segment load command.
+ ///
+ /// \param NumSections The number of sections in this segment.
+ /// \param SectionDataSize The total size of the sections.
+ void WriteSegmentLoadCommand(unsigned NumSections,
+ uint64_t VMSize,
+ uint64_t SectionDataStartOffset,
+ uint64_t SectionDataSize);
+
+ void WriteSection(const MCAssembler &Asm, const MCAsmLayout &Layout,
+ const MCSectionData &SD, uint64_t FileOffset,
+ uint64_t RelocationsStart, unsigned NumRelocations);
+
+ void WriteSymtabLoadCommand(uint32_t SymbolOffset, uint32_t NumSymbols,
+ uint32_t StringTableOffset,
+ uint32_t StringTableSize);
+
+ void WriteDysymtabLoadCommand(uint32_t FirstLocalSymbol,
+ uint32_t NumLocalSymbols,
+ uint32_t FirstExternalSymbol,
+ uint32_t NumExternalSymbols,
+ uint32_t FirstUndefinedSymbol,
+ uint32_t NumUndefinedSymbols,
+ uint32_t IndirectSymbolOffset,
+ uint32_t NumIndirectSymbols);
+
+ void WriteNlist(MachSymbolData &MSD, const MCAsmLayout &Layout);
+
+ void WriteLinkeditLoadCommand(uint32_t Type, uint32_t DataOffset,
+ uint32_t DataSize);
+
+ void WriteLinkerOptionsLoadCommand(const std::vector<std::string> &Options);
+
+ // FIXME: We really need to improve the relocation validation. Basically, we
+ // want to implement a separate computation which evaluates the relocation
+ // entry as the linker would, and verifies that the resultant fixup value is
+ // exactly what the encoder wanted. This will catch several classes of
+ // problems:
+ //
+ // - Relocation entry bugs, the two algorithms are unlikely to have the same
+ // exact bug.
+ //
+ // - Relaxation issues, where we forget to relax something.
+ //
+ // - Input errors, where something cannot be correctly encoded. 'as' allows
+ // these through in many cases.
+
+ void addRelocation(const MCSectionData *SD,
+ MachO::any_relocation_info &MRE) {
+ Relocations[SD].push_back(MRE);
+ }
+
+ void RecordScatteredRelocation(const MCAssembler &Asm,
+ const MCAsmLayout &Layout,
+ const MCFragment *Fragment,
+ const MCFixup &Fixup, MCValue Target,
+ unsigned Log2Size,
+ uint64_t &FixedValue);
+
+ void RecordTLVPRelocation(const MCAssembler &Asm,
+ const MCAsmLayout &Layout,
+ const MCFragment *Fragment,
+ const MCFixup &Fixup, MCValue Target,
+ uint64_t &FixedValue);
+
+ void RecordRelocation(const MCAssembler &Asm, const MCAsmLayout &Layout,
+ const MCFragment *Fragment, const MCFixup &Fixup,
+ MCValue Target, bool &IsPCRel,
+ uint64_t &FixedValue) override;
+
+ void BindIndirectSymbols(MCAssembler &Asm);
+
+ /// ComputeSymbolTable - Compute the symbol table data
+ ///
+ /// \param StringTable [out] - The string table data.
+ void ComputeSymbolTable(MCAssembler &Asm, SmallString<256> &StringTable,
+ std::vector<MachSymbolData> &LocalSymbolData,
+ std::vector<MachSymbolData> &ExternalSymbolData,
+ std::vector<MachSymbolData> &UndefinedSymbolData);
+
+ void computeSectionAddresses(const MCAssembler &Asm,
+ const MCAsmLayout &Layout);
+
+ void markAbsoluteVariableSymbols(MCAssembler &Asm,
+ const MCAsmLayout &Layout);
+ void ExecutePostLayoutBinding(MCAssembler &Asm,
+ const MCAsmLayout &Layout) override;
+
+ bool IsSymbolRefDifferenceFullyResolvedImpl(const MCAssembler &Asm,
+ const MCSymbolData &DataA,
+ const MCFragment &FB,
+ bool InSet,
+ bool IsPCRel) const override;
+
+ void WriteObject(MCAssembler &Asm, const MCAsmLayout &Layout) override;
};
+
/// \brief Construct a new Mach-O writer instance.
///
/// This routine takes ownership of the target writer subclass.
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