]> git.saurik.com Git - apple/ld64.git/blobdiff - src/ld/parsers/macho_relocatable_file.cpp
ld64-236.3.tar.gz
[apple/ld64.git] / src / ld / parsers / macho_relocatable_file.cpp
index b49d63f6580a78b610480f4c506588c782e97434..ad5720ed1212e2b3b060c558df673658b49c5eb6 100644 (file)
@@ -92,9 +92,10 @@ public:
        virtual ObjcConstraint                                                          objCConstraint() const                  { return _objConstraint; }
        virtual uint32_t                                                                        cpuSubType() const                              { return _cpuSubType; }
        virtual DebugInfoKind                                                           debugInfo() const                               { return _debugInfoKind; }
-       virtual const std::vector<ld::relocatable::File::Stab>* stabs() const                                   { return &_stabs; }
+       virtual const std::vector<ld::relocatable::File::Stab>* stabs() const                           { return &_stabs; }
        virtual bool                                                                            canScatterAtoms() const                 { return _canScatterAtoms; }
        virtual const char*                                                                     translationUnitSource() const;
+       virtual LinkerOptionsList*                                                      linkerOptions() const                   { return &_linkerOptions; }
        
        const uint8_t*                                                                          fileContent()                                   { return _fileContent; }
 private:
@@ -123,6 +124,7 @@ private:
        ld::File::ObjcConstraint                                _objConstraint;
        uint32_t                                                                _cpuSubType;
        bool                                                                    _canScatterAtoms;
+       std::vector<std::vector<const char*> >  _linkerOptions;
 };
 
 
@@ -154,6 +156,7 @@ public:
        virtual unsigned long                   contentHash(const class Atom<A>* atom, const ld::IndirectBindingTable& ind) const { return 0; }
        virtual bool                                    canCoalesceWith(const class Atom<A>* atom, const ld::Atom& rhs, 
                                                                                                        const ld::IndirectBindingTable& ind) const { return false; }
+       virtual bool                                    ignoreLabel(const char* label) const { return false; }
        static const char*                              makeSectionName(const macho_section<typename A::P>* s);
 
 protected:     
@@ -167,6 +170,7 @@ protected:
 
        Atom<A>*                                                findContentAtomByAddress(pint_t addr, class Atom<A>* start, class Atom<A>* end);
        uint32_t                                                x86_64PcRelOffset(uint8_t r_type);
+       void                                                    addLOH(class Parser<A>& parser, int kind, int count, const uint64_t addrs[]);
        static const char*                              makeSegmentName(const macho_section<typename A::P>* s);
        static bool                                             readable(const macho_section<typename A::P>* s);
        static bool                                             writable(const macho_section<typename A::P>* s);
@@ -235,7 +239,7 @@ public:
        typedef typename A::P::uint_t                   pint_t;
        typedef libunwind::CFI_Atom_Info<OAS>   CFI_Atom_Info;
        
-       void                            cfiParse(class Parser<A>& parser, uint8_t* buffer, CFI_Atom_Info cfiArray[], uint32_t cfiCount);
+       void                            cfiParse(class Parser<A>& parser, uint8_t* buffer, CFI_Atom_Info cfiArray[], uint32_t& cfiCount, const pint_t cuStarts[], uint32_t cuCount);
        bool                            needsRelocating();
 
        static bool                     bigEndian();
@@ -274,6 +278,7 @@ public:
 
        uint32_t                                count();
        void                                    parse(class Parser<A>& parser, uint32_t cnt, Info array[]);
+       static bool                             encodingMeansUseDwarf(compact_unwind_encoding_t enc);
        
        
 private:
@@ -379,16 +384,17 @@ protected:
        
        virtual bool                                            addFollowOnFixups() const               { return false; }
        virtual const char*                                     unlabeledAtomName(Parser<A>& parser, pint_t addr) = 0;
-       virtual ld::Atom::SymbolTableInclusion  symbolTableInclusion()          { return ld::Atom::symbolTableNotIn; }
+       virtual ld::Atom::SymbolTableInclusion  symbolTableInclusion();
        virtual pint_t                                          elementSizeAtAddress(pint_t addr) = 0;
        virtual ld::Atom::Scope                         scopeAtAddress(Parser<A>& parser, pint_t addr) { return ld::Atom::scopeLinkageUnit; }
        virtual bool                                            useElementAt(Parser<A>& parser, 
                                                                                                struct Parser<A>::LabelAndCFIBreakIterator& it, pint_t addr) = 0;
        virtual ld::Atom::Definition            definition()                                    { return ld::Atom::definitionRegular; }
        virtual ld::Atom::Combine                       combine(Parser<A>& parser, pint_t addr) = 0;
-       virtual bool                                            ignoreLabel(const char* label)  { return (label[0] == 'L'); }
+       virtual bool                                            ignoreLabel(const char* label) const { return (label[0] == 'L'); }
 };
 
+
 template <typename A>
 class FixedSizeSection : public ImplicitSizeSection<A>
 {
@@ -481,7 +487,7 @@ protected:
        virtual pint_t                                  elementSizeAtAddress(pint_t addr)               { return sizeof(pint_t); }
        virtual ld::Atom::Scope                 scopeAtAddress(Parser<A>& parser, pint_t addr);
        virtual ld::Atom::Combine               combine(Parser<A>&, pint_t);
-       virtual bool                                    ignoreLabel(const char* label)                  { return true; }
+       virtual bool                                    ignoreLabel(const char* label) const    { return true; }
        virtual unsigned long                   contentHash(const class Atom<A>* atom, const ld::IndirectBindingTable& ind) const;
        virtual bool                                    canCoalesceWith(const class Atom<A>* atom, const ld::Atom& rhs, 
                                                                                                        const ld::IndirectBindingTable& ind) const;
@@ -505,7 +511,7 @@ protected:
        virtual const char*                             unlabeledAtomName(Parser<A>&, pint_t)   { return "CFString"; }
        virtual pint_t                                  elementSizeAtAddress(pint_t addr)               { return 4*sizeof(pint_t); }
        virtual ld::Atom::Combine               combine(Parser<A>&, pint_t)                             { return ld::Atom::combineByNameAndReferences; }
-       virtual bool                                    ignoreLabel(const char* label)                  { return true; }
+       virtual bool                                    ignoreLabel(const char* label) const    { return true; }
        virtual unsigned long                   contentHash(const class Atom<A>* atom, const ld::IndirectBindingTable& ind) const;
        virtual bool                                    canCoalesceWith(const class Atom<A>* atom, const ld::Atom& rhs, 
                                                                                                        const ld::IndirectBindingTable& ind) const;
@@ -533,7 +539,7 @@ protected:
        virtual ld::Atom::SymbolTableInclusion  symbolTableInclusion()                  { return ld::Atom::symbolTableIn; }
        virtual pint_t                                  elementSizeAtAddress(pint_t addr);
        virtual ld::Atom::Combine               combine(Parser<A>&, pint_t)                             { return ld::Atom::combineNever; }
-       virtual bool                                    ignoreLabel(const char* label)                  { return true; }
+       virtual bool                                    ignoreLabel(const char* label) const    { return true; }
        virtual unsigned long                   contentHash(const class Atom<A>* atom, const ld::IndirectBindingTable& ind) const
                                                                                                                                                        { return 0; }
        virtual bool                                    canCoalesceWith(const class Atom<A>* atom, const ld::Atom& rhs, 
@@ -555,7 +561,7 @@ protected:
        virtual const char*                             unlabeledAtomName(Parser<A>&, pint_t)   { return "objc-class-ref"; }
        virtual pint_t                                  elementSizeAtAddress(pint_t addr)               { return sizeof(pint_t); }
        virtual ld::Atom::Combine               combine(Parser<A>&, pint_t)                             { return ld::Atom::combineByNameAndReferences; }
-       virtual bool                                    ignoreLabel(const char* label)                  { return true; }
+       virtual bool                                    ignoreLabel(const char* label) const    { return true; }
        virtual unsigned long                   contentHash(const class Atom<A>* atom, const ld::IndirectBindingTable& ind) const;
        virtual bool                                    canCoalesceWith(const class Atom<A>* atom, const ld::Atom& rhs, 
                                                                                                        const ld::IndirectBindingTable& ind) const;
@@ -578,7 +584,7 @@ protected:
        virtual const char*                             unlabeledAtomName(Parser<A>&, pint_t)   { return "objc-cat-list"; }
        virtual pint_t                                  elementSizeAtAddress(pint_t addr)               { return sizeof(pint_t); }
        virtual ld::Atom::Combine               combine(Parser<A>&, pint_t)                             { return ld::Atom::combineNever; }
-       virtual bool                                    ignoreLabel(const char* label)                  { return true; }
+       virtual bool                                    ignoreLabel(const char* label) const    { return true; }
 private:
        const char*                                             targetClassName(const class Atom<A>* atom, const ld::IndirectBindingTable& ind) const;
 };
@@ -597,7 +603,7 @@ protected:
        virtual const char*                             unlabeledAtomName(Parser<A>&, pint_t)   { return "pointer-to-literal-cstring"; }
        virtual pint_t                                  elementSizeAtAddress(pint_t addr)               { return sizeof(pint_t); }
        virtual ld::Atom::Combine               combine(Parser<A>&, pint_t)                             { return ld::Atom::combineByNameAndReferences; }
-       virtual bool                                    ignoreLabel(const char* label)                  { return true; }
+       virtual bool                                    ignoreLabel(const char* label) const    { return true; }
        virtual unsigned long                   contentHash(const class Atom<A>* atom, const ld::IndirectBindingTable& ind) const;
        virtual bool                                    canCoalesceWith(const class Atom<A>* atom, const ld::Atom& rhs, 
                                                                                                        const ld::IndirectBindingTable& ind) const;
@@ -635,7 +641,7 @@ protected:
        virtual Atom<A>*                                findAtomByAddress(pint_t addr);
        virtual const char*                             unlabeledAtomName(Parser<A>&, pint_t)   { return "cstring"; }
        virtual pint_t                                  elementSizeAtAddress(pint_t addr);
-       virtual bool                                    ignoreLabel(const char* label);
+       virtual bool                                    ignoreLabel(const char* label) const;
        virtual bool                                    useElementAt(Parser<A>& parser, 
                                                                                                struct Parser<A>::LabelAndCFIBreakIterator& it, pint_t addr);
        virtual ld::Atom::Combine               combine(Parser<A>&, pint_t)                             { return ld::Atom::combineByNameAndContent; }
@@ -671,7 +677,7 @@ class Atom : public ld::Atom
 {
 public:
        // overrides of ld::Atom
-       virtual ld::File*                                                       file() const            { return &sect().file(); }
+       virtual const ld::File*                                         file() const;
        virtual const char*                                                     translationUnitSource() const
                                                                                                                                        { return sect().file().translationUnitSource(); }
        virtual const char*                                                     name() const            { return _name; }
@@ -689,6 +695,7 @@ public:
        virtual ld::Atom::UnwindInfo::iterator          endUnwind()     const   { return &machofile()._unwindInfos[_unwindInfoStartIndex+_unwindInfoCount];  }
        virtual ld::Atom::LineInfo::iterator            beginLineInfo() const{ return &machofile()._lineInfos[_lineInfoStartIndex]; }
        virtual ld::Atom::LineInfo::iterator            endLineInfo() const { return &machofile()._lineInfos[_lineInfoStartIndex+_lineInfoCount];  }
+       virtual void                                                            setFile(const ld::File* f);
 
 private:
 
@@ -714,7 +721,7 @@ public:
                                                                                                                                                        throwf("too may fixups in %s", name()); ++_fixupsCount; }
                        const uint8_t*                                          contentPointer() const;
                        uint32_t                                                        fixupCount() const { return _fixupsCount; }
-                       void                                                            verifyAlignment() const;
+                       void                                                            verifyAlignment(const macho_section<typename A::P>&) const;
        
        typedef typename A::P                                           P;
        typedef typename A::P::E                                        E;
@@ -748,7 +755,7 @@ public:
                                                                                                                                if ( _scope == ld::Atom::scopeGlobal && 
                                                                                                                                                (sym.n_desc() & (N_WEAK_DEF|N_WEAK_REF)) == (N_WEAK_DEF|N_WEAK_REF) )
                                                                                                                                        this->setAutoHide();
-                                                                                                                                       this->verifyAlignment();
+                                                                                                                                       this->verifyAlignment(*sct.machoSection());
                                                                                                                        }
 
 private:
@@ -768,10 +775,27 @@ private:
                                                                                                _fixupsCount                    : kFixupCountBits,
                                                                                                _lineInfoCount                  : kLineInfoCountBits,
                                                                                                _unwindInfoCount                : kUnwindInfoCountBits;
-
+                                                                                               
+       static std::map<const ld::Atom*, const ld::File*> _s_fileOverride;
 };
 
+template <typename A>
+std::map<const ld::Atom*, const ld::File*> Atom<A>::_s_fileOverride;
 
+template <typename A>
+void Atom<A>::setFile(const ld::File* f) {
+       _s_fileOverride[this] = f;
+}
+
+template <typename A>
+const ld::File* Atom<A>::file() const
+{
+       std::map<const ld::Atom*, const ld::File*>::iterator pos = _s_fileOverride.find(this);
+       if ( pos != _s_fileOverride.end() )
+               return pos->second;
+               
+       return &sect().file();
+}
 
 template <typename A>
 void Atom<A>::setFixupsRange(uint32_t startIndex, uint32_t count)
@@ -838,7 +862,7 @@ void Atom<A>::copyRawContent(uint8_t buffer[]) const
 }
 
 template <>
-void Atom<arm>::verifyAlignment() const
+void Atom<arm>::verifyAlignment(const macho_section<P>&) const
 {
        if ( (this->section().type() == ld::Section::typeCode) && ! isThumb() ) {
                if ( ((_objAddress % 4) != 0) || (this->alignment().powerOf2 < 2) )
@@ -846,8 +870,19 @@ void Atom<arm>::verifyAlignment() const
        }
 }
 
+#if SUPPORT_ARCH_arm64
+template <>
+void Atom<arm64>::verifyAlignment(const macho_section<P>& sect) const
+{
+       if ( (this->section().type() == ld::Section::typeCode) && (sect.size() != 0) ) {
+               if ( ((_objAddress % 4) != 0) || (this->alignment().powerOf2 < 2) )
+                       warning("arm64 function not 4-byte aligned: %s from %s", this->name(), this->file()->path());
+       }
+}
+#endif
+
 template <typename A>
-void Atom<A>::verifyAlignment() const
+void Atom<A>::verifyAlignment(const macho_section<P>&) const
 {
 }
 
@@ -865,7 +900,9 @@ public:
                                                                                                                        const char* path, time_t modTime, ld::File::Ordinal ordinal,
                                                                                                                         const ParserOptions& opts) {
                                                                                                                                Parser p(fileContent, fileLength, path, modTime, 
-                                                                                                                                               ordinal, opts.convertUnwindInfo);
+                                                                                                                                               ordinal, opts.warnUnwindConversionProblems,
+                                                                                                                                               opts.keepDwarfUnwind, opts.forceDwarfConversion,
+                                                                                                                                               opts.neverConvertDwarf, opts.verboseOptimizationHints);
                                                                                                                                return p.parse(opts);
                                                                                                                }
 
@@ -934,7 +971,7 @@ public:
                _allFixups.push_back(FixupInAtom(src, c, k)); 
        }
 
-
+       const char*                                                                             path() { return _path; }
        uint32_t                                                                                symbolCount() { return _symbolCount; }
        uint32_t                                                                                indirectSymbol(uint32_t indirectIndex);
        const macho_nlist<P>&                                                   symbolFromIndex(uint32_t index);
@@ -971,11 +1008,19 @@ public:
        unsigned int                                                                    stubsSectionNum() { return _stubsSectionNum; }
        void                                                                                    addDtraceExtraInfos(const SourceLocation& src, const char* provider);
        const char*                                                                             scanSymbolTableForAddress(uint64_t addr);
-       bool                                                                                    convertUnwindInfo() { return _convertUnwindInfo; }
+       bool                                                                                    warnUnwindConversionProblems() { return _warnUnwindConversionProblems; }
        bool                                                                                    hasDataInCodeLabels() { return _hasDataInCodeLabels; }
-
+       bool                                                                                    keepDwarfUnwind() { return _keepDwarfUnwind; }
+       bool                                                                                    forceDwarfConversion() { return _forceDwarfConversion; }
+       bool                                                                                    verboseOptimizationHints() { return _verboseOptimizationHints; }
+       bool                                                                                    neverConvertDwarf() { return _neverConvertDwarf; }
+       
        macho_data_in_code_entry<P>*                                    dataInCodeStart() { return _dataInCodeStart; }
        macho_data_in_code_entry<P>*                                    dataInCodeEnd()   { return _dataInCodeEnd; }
+       const uint8_t*                                                                  optimizationHintsStart() { return _lohStart; }
+       const uint8_t*                                                                  optimizationHintsEnd() { return _lohEnd; }
+       bool                                                                                    hasOptimizationHints() { return _lohStart != _lohEnd; }
+
        
        void                                                    addFixups(const SourceLocation& src, ld::Fixup::Kind kind, const TargetDesc& target);
        void                                                    addFixups(const SourceLocation& src, ld::Fixup::Kind kind, const TargetDesc& target, const TargetDesc& picBase);
@@ -989,7 +1034,7 @@ public:
                                                                        : sortedSymbolIndexes(ssa), sortedSymbolCount(ssc), cfiStartsArray(cfisa), 
                                                                                cfiStartsCount(cfisc), fileHasOverlappingSymbols(ols),
                                                                                newSection(false), cfiIndex(0), symIndex(0) {}
-               bool                                    next(Parser<A>& parser, uint32_t sectNum, pint_t startAddr, pint_t endAddr, 
+               bool                                    next(Parser<A>& parser, const Section<A>& sect, uint32_t sectNum, pint_t startAddr, pint_t endAddr, 
                                                                                pint_t* addr, pint_t* size, const macho_nlist<P>** sym);
                pint_t                                  peek(Parser<A>& parser, pint_t startAddr, pint_t endAddr);
                void                                    beginSection() { newSection = true; symIndex = 0; }
@@ -1050,8 +1095,9 @@ private:
        
 
                                                                                                        Parser(const uint8_t* fileContent, uint64_t fileLength, 
-                                                                                                                       const char* path, time_t modTime, 
-                                                                                                                       ld::File::Ordinal ordinal, bool convertUnwindInfo);
+                                                                                                                       const char* path, time_t modTime, ld::File::Ordinal ordinal, 
+                                                                                                                       bool warnUnwindConversionProblems, bool keepDwarfUnwind,
+                                                                                                                       bool forceDwarfConversion, bool neverConvertDwarf, bool verboseOptimizationHints);
        ld::relocatable::File*                                                  parse(const ParserOptions& opts);
        uint8_t                                                                                 loadCommandSizeMask();
        bool                                                                                    parseLoadCommands();
@@ -1095,6 +1141,8 @@ private:
        bool                                                                            _hasUUID;
        macho_data_in_code_entry<P>*                            _dataInCodeStart;
        macho_data_in_code_entry<P>*                            _dataInCodeEnd;
+       const uint8_t*                                                          _lohStart;
+       const uint8_t*                                                          _lohEnd;
                
        // filled in by parse()
        CFISection<A>*                                                          _EHFrameSection;
@@ -1106,8 +1154,12 @@ private:
        bool                                                                            _hasLongBranchStubs;
        bool                                                                            _AppleObjc; // FSF has objc that uses different data layout
        bool                                                                            _overlappingSymbols;
-       bool                                                                            _convertUnwindInfo;
+       bool                                                                            _warnUnwindConversionProblems;
        bool                                                                            _hasDataInCodeLabels;
+       bool                                                                            _keepDwarfUnwind;
+       bool                                                                            _forceDwarfConversion;
+       bool                                                                            _neverConvertDwarf;
+       bool                                                                            _verboseOptimizationHints;
        unsigned int                                                            _stubsSectionNum;
        const macho_section<P>*                                         _stubsMachOSection;
        std::vector<const char*>                                        _dtraceProviderInfo;
@@ -1118,7 +1170,8 @@ private:
 
 template <typename A>
 Parser<A>::Parser(const uint8_t* fileContent, uint64_t fileLength, const char* path, time_t modTime, 
-                                       ld::File::Ordinal ordinal, bool convertDUI)
+                                       ld::File::Ordinal ordinal, bool convertDUI, bool keepDwarfUnwind, bool forceDwarfConversion, 
+                                       bool neverConvertDwarf, bool verboseOptimizationHints)
                : _fileContent(fileContent), _fileLength(fileLength), _path(path), _modTime(modTime),
                        _ordinal(ordinal), _file(NULL),
                        _symbols(NULL), _symbolCount(0), _strings(NULL), _stringsSize(0),
@@ -1126,10 +1179,14 @@ Parser<A>::Parser(const uint8_t* fileContent, uint64_t fileLength, const char* p
                        _undefinedStartIndex(0), _undefinedEndIndex(0), 
                        _sectionsStart(NULL), _machOSectionsCount(0), _hasUUID(false), 
                        _dataInCodeStart(NULL), _dataInCodeEnd(NULL),
+                       _lohStart(NULL), _lohEnd(NULL),
                        _EHFrameSection(NULL), _compactUnwindSection(NULL), _absoluteSection(NULL),
                        _tentativeDefinitionCount(0), _absoluteSymbolCount(0),
                        _symbolsInSections(0), _hasLongBranchStubs(false),  _AppleObjc(false),
-                       _overlappingSymbols(false), _convertUnwindInfo(convertDUI), _hasDataInCodeLabels(false), 
+                       _overlappingSymbols(false), _warnUnwindConversionProblems(convertDUI), _hasDataInCodeLabels(false),
+                       _keepDwarfUnwind(keepDwarfUnwind), _forceDwarfConversion(forceDwarfConversion),
+                       _neverConvertDwarf(neverConvertDwarf),
+                       _verboseOptimizationHints(verboseOptimizationHints),
                        _stubsSectionNum(0), _stubsMachOSection(NULL)
 {
 }
@@ -1183,6 +1240,19 @@ bool Parser<arm>::validFile(const uint8_t* fileContent, bool subtypeMustMatch, c
 }
 
 
+template <>
+bool Parser<arm64>::validFile(const uint8_t* fileContent, bool subtypeMustMatch, cpu_subtype_t subtype)
+{
+       const macho_header<P>* header = (const macho_header<P>*)fileContent;
+       if ( header->magic() != MH_MAGIC_64 )
+               return false;
+       if ( header->cputype() != CPU_TYPE_ARM64 )
+               return false;
+       if ( header->filetype() != MH_OBJECT )
+               return false;
+       return true;
+}
+
 
 template <>
 const char* Parser<x86>::fileKind(const uint8_t* fileContent)
@@ -1222,6 +1292,18 @@ const char* Parser<arm>::fileKind(const uint8_t* fileContent)
        return "arm???";
 }
 
+#if SUPPORT_ARCH_arm64
+template <>
+const char* Parser<arm64>::fileKind(const uint8_t* fileContent)
+{
+       const macho_header<P>* header = (const macho_header<P>*)fileContent;
+       if ( header->magic() != MH_MAGIC )
+               return NULL;
+       if ( header->cputype() != CPU_TYPE_ARM64 )
+               return NULL;
+       return "arm64";
+}
+#endif
 
 template <typename A>
 bool Parser<A>::hasObjC2Categories(const uint8_t* fileContent)
@@ -1322,7 +1404,7 @@ typename A::P::uint_t Parser<A>::LabelAndCFIBreakIterator::peek(Parser<A>& parse
 // was becuase of a label, the symbol). Returns false when no more chunks.
 //
 template <typename A>
-bool Parser<A>::LabelAndCFIBreakIterator::next(Parser<A>& parser, uint32_t sectNum, pint_t startAddr, pint_t endAddr, 
+bool Parser<A>::LabelAndCFIBreakIterator::next(Parser<A>& parser, const Section<A>& sect, uint32_t sectNum, pint_t startAddr, pint_t endAddr, 
                                                                                                pint_t* addr, pint_t* size, const macho_nlist<P>** symbol)
 {
        // may not be a label on start of section, but need atom demarcation there
@@ -1331,10 +1413,12 @@ bool Parser<A>::LabelAndCFIBreakIterator::next(Parser<A>& parser, uint32_t sectN
                // advance symIndex until we get to the first label at or past the start of this section
                while ( symIndex < sortedSymbolCount ) {
                        const macho_nlist<P>& sym = parser.symbolFromIndex(sortedSymbolIndexes[symIndex]);
-                       pint_t nextSymbolAddr = sym.n_value();
-                       //fprintf(stderr, "sectNum=%d, nextSymbolAddr=0x%08llX, name=%s\n", sectNum, (uint64_t)nextSymbolAddr, parser.nameFromSymbol(sym));
-                       if ( (nextSymbolAddr > startAddr) || ((nextSymbolAddr == startAddr) && (sym.n_sect() == sectNum)) )
-                               break;
+                       if ( ! sect.ignoreLabel(parser.nameFromSymbol(sym)) ) {
+                               pint_t nextSymbolAddr = sym.n_value();
+                               //fprintf(stderr, "sectNum=%d, nextSymbolAddr=0x%08llX, name=%s\n", sectNum, (uint64_t)nextSymbolAddr, parser.nameFromSymbol(sym));
+                               if ( (nextSymbolAddr > startAddr) || ((nextSymbolAddr == startAddr) && (sym.n_sect() == sectNum)) )
+                                       break;
+                       }
                        ++symIndex;
                }
                if ( symIndex < sortedSymbolCount ) {
@@ -1381,7 +1465,19 @@ bool Parser<A>::LabelAndCFIBreakIterator::next(Parser<A>& parser, uint32_t sectN
                        *symbol = NULL;
                        return true;
                }
-               // no symbols left in whole file, so entire section is one chunk
+               // no symbols in section, check CFI
+               if ( cfiIndex < cfiStartsCount ) {
+                       pint_t nextCfiAddr = cfiStartsArray[cfiIndex];
+                       if ( nextCfiAddr < endAddr ) {
+                               // use cfi
+                               ++cfiIndex;
+                               *addr = nextCfiAddr;
+                               *size = peek(parser, startAddr, endAddr) - nextCfiAddr;
+                               *symbol = NULL;
+                               return true;
+                       }
+               }
+               // no cfi, so whole section is one chunk
                *addr = startAddr;
                *size = endAddr - startAddr;
                *symbol = NULL;
@@ -1459,6 +1555,16 @@ bool Parser<A>::LabelAndCFIBreakIterator::next(Parser<A>& parser, uint32_t sectN
        return false;
 }
 
+#define STACK_ALLOC_IF_SMALL(_type, _name, _actual_count, _maxCount) \
+       _type*  _name = NULL;   \
+       uint32_t _name##_count = 1; \
+       if ( _actual_count > _maxCount ) \
+               _name = (_type*)malloc(sizeof(_type) * _actual_count); \
+       else \
+               _name##_count = _actual_count; \
+       _type  _name##_buffer[_name##_count]; \
+       if ( _name == NULL ) \
+               _name = _name##_buffer;
 
 
 template <typename A>
@@ -1475,7 +1581,7 @@ ld::relocatable::File* Parser<A>::parse(const ParserOptions& opts)
        if ( ! parseLoadCommands() )
                return _file;
        
-       // make array of 
+       // make array of
        uint32_t sortedSectionIndexes[_machOSectionsCount];
        this->makeSortedSectionsArray(sortedSectionIndexes);
        
@@ -1491,40 +1597,46 @@ ld::relocatable::File* Parser<A>::parse(const ParserOptions& opts)
        uint32_t countOfCUs = 0;
        if ( _compactUnwindSection != NULL )
                countOfCUs = _compactUnwindSection->count();
-       uint8_t cuInfoBuffer[sizeof(typename CUSection<A>::Info) * countOfCUs];
-       typename CUSection<A>::Info*  cuInfoArray = (typename CUSection<A>::Info*)cuInfoBuffer;
+       // stack allocate (if not too large) cuInfoBuffer
+       STACK_ALLOC_IF_SMALL(typename CUSection<A>::Info, cuInfoArray, countOfCUs, 1024);
        if ( countOfCUs != 0 )
                _compactUnwindSection->parse(*this, countOfCUs, cuInfoArray);
+
+       // create lists of address that already have compact unwind and thus don't need the dwarf parsed
+       unsigned cuLsdaCount = 0;
+       pint_t cuStarts[countOfCUs];
+       for (uint32_t i=0; i < countOfCUs; ++i) {
+               if ( CUSection<A>::encodingMeansUseDwarf(cuInfoArray[i].compactUnwindInfo) )
+                       cuStarts[i] = -1;
+               else
+                       cuStarts[i] = cuInfoArray[i].functionStartAddress;
+               if ( cuInfoArray[i].lsdaAddress != 0 )
+                       ++cuLsdaCount;
+       }
+       
        
        // if it exists, do special early parsing of __eh_frame section 
-       // stack allocate array of CFI_Atom_Info
+       // stack allocate (if not too large) array of CFI_Atom_Info
        uint32_t countOfCFIs = 0;
        if ( _EHFrameSection != NULL )
                countOfCFIs = _EHFrameSection->cfiCount();
-       typename CFISection<A>::CFI_Atom_Info  cfiArray[countOfCFIs];
+       STACK_ALLOC_IF_SMALL(typename CFISection<A>::CFI_Atom_Info, cfiArray, countOfCFIs, 1024);
+       
        // stack allocate (if not too large) a copy of __eh_frame to apply relocations to
-       uint8_t* ehBuffer = NULL;
-       uint32_t stackAllocSize = 0;
-       if ( (countOfCFIs != 0) && _EHFrameSection->needsRelocating() ) {
-               uint32_t sectSize = _EHFrameSection->machoSection()->size();
-               if ( sectSize > 50*1024 )
-                       ehBuffer = (uint8_t*)malloc(sectSize);
-               else
-                       stackAllocSize = sectSize;
-       }
-       uint32_t ehStackBuffer[1+stackAllocSize/4]; // make 4-byte aligned stack bufffer
-       if ( ehBuffer == NULL )
-               ehBuffer = (uint8_t*)&ehStackBuffer;
+       uint32_t sectSize = 4;
+       if ( (countOfCFIs != 0) && _EHFrameSection->needsRelocating() ) 
+               sectSize = _EHFrameSection->machoSection()->size()+4;
+       STACK_ALLOC_IF_SMALL(uint8_t, ehBuffer, sectSize, 50*1024);
        uint32_t cfiStartsCount = 0;
        if ( countOfCFIs != 0 ) {
-               _EHFrameSection->cfiParse(*this, ehBuffer, cfiArray, countOfCFIs);
+               _EHFrameSection->cfiParse(*this, ehBuffer, cfiArray, countOfCFIs, cuStarts, countOfCUs);
                // count functions and lsdas
                for(uint32_t i=0; i < countOfCFIs; ++i) {
                        if ( cfiArray[i].isCIE )
                                continue;
-                       //fprintf(stderr, "cfiArray[i].func = 0x%08llX, cfiArray[i].lsda = 0x%08llX, encoding=0x%08X\n", 
-                       //                      (uint64_t)cfiArray[i].u.fdeInfo.function.targetAddress, 
-                       //                      (uint64_t)cfiArray[i].u.fdeInfo.lsda.targetAddress, 
+                       //fprintf(stderr, "cfiArray[i].func = 0x%08llX, cfiArray[i].lsda = 0x%08llX, encoding=0x%08X\n",
+                       //                      (uint64_t)cfiArray[i].u.fdeInfo.function.targetAddress,
+                       //                      (uint64_t)cfiArray[i].u.fdeInfo.lsda.targetAddress,
                        //                      cfiArray[i].u.fdeInfo.compactUnwindInfo);
                        if ( cfiArray[i].u.fdeInfo.function.targetAddress != CFI_INVALID_ADDRESS )
                                ++cfiStartsCount;
@@ -1535,23 +1647,41 @@ ld::relocatable::File* Parser<A>::parse(const ParserOptions& opts)
        CFI_CU_InfoArrays cfis(cfiArray, countOfCFIs, cuInfoArray, countOfCUs);
        
        // create sorted array of function starts and lsda starts
-       pint_t cfiStartsArray[cfiStartsCount];
+       pint_t cfiStartsArray[cfiStartsCount+cuLsdaCount];
        uint32_t countOfFDEs = 0;
+       uint32_t cfiStartsArrayCount = 0;
        if ( countOfCFIs != 0 ) {
-               int index = 0;
                for(uint32_t i=0; i < countOfCFIs; ++i) {
                        if ( cfiArray[i].isCIE )
                                continue;
                        if ( cfiArray[i].u.fdeInfo.function.targetAddress != CFI_INVALID_ADDRESS )
-                               cfiStartsArray[index++] = cfiArray[i].u.fdeInfo.function.targetAddress;
+                               cfiStartsArray[cfiStartsArrayCount++] = cfiArray[i].u.fdeInfo.function.targetAddress;
                        if ( cfiArray[i].u.fdeInfo.lsda.targetAddress != CFI_INVALID_ADDRESS )
-                               cfiStartsArray[index++] = cfiArray[i].u.fdeInfo.lsda.targetAddress;
+                               cfiStartsArray[cfiStartsArrayCount++] = cfiArray[i].u.fdeInfo.lsda.targetAddress;
                        ++countOfFDEs;
                }
-               ::qsort(cfiStartsArray, cfiStartsCount, sizeof(pint_t), pointerSorter);
+       }
+       if ( cuLsdaCount != 0 ) {
+               // merge in an lsda info from compact unwind
+               for (uint32_t i=0; i < countOfCUs; ++i) {
+                       if ( cuInfoArray[i].lsdaAddress == 0 )
+                               continue;
+                       // append to cfiStartsArray if not already in that list
+                       bool found = false;
+                       for(uint32_t j=0; j < cfiStartsArrayCount; ++j) {
+                               if ( cfiStartsArray[j] == cuInfoArray[i].lsdaAddress )
+                                       found = true;
+                       }
+                       if ( ! found ) {
+                               cfiStartsArray[cfiStartsArrayCount++] = cuInfoArray[i].lsdaAddress;
+                       }
+               }
+       }
+       if ( cfiStartsArrayCount != 0 ) {
+               ::qsort(cfiStartsArray, cfiStartsArrayCount, sizeof(pint_t), pointerSorter);
        #ifndef NDEBUG
                // scan for FDEs claming the same function
-               for(int i=1; i < index; ++i) {
+               for(uint32_t i=1; i < cfiStartsArrayCount; ++i) {
                        assert( cfiStartsArray[i] != cfiStartsArray[i-1] );
                }
        #endif  
@@ -1562,7 +1692,7 @@ ld::relocatable::File* Parser<A>::parse(const ParserOptions& opts)
 
        // figure out how many atoms will be allocated and allocate
        LabelAndCFIBreakIterator breakIterator(sortedSymbolIndexes, _symbolsInSections, cfiStartsArray, 
-                                                                                       cfiStartsCount, _overlappingSymbols);
+                                                                                       cfiStartsArrayCount, _overlappingSymbols);
        uint32_t computedAtomCount = 0;
        for (uint32_t i=0; i < sectionsCount; ++i ) {
                breakIterator.beginSection();
@@ -1577,7 +1707,7 @@ ld::relocatable::File* Parser<A>::parse(const ParserOptions& opts)
        
        // have each section append atoms to _atomsArray
        LabelAndCFIBreakIterator breakIterator2(sortedSymbolIndexes, _symbolsInSections, cfiStartsArray, 
-                                                                                               cfiStartsCount, _overlappingSymbols);
+                                                                                               cfiStartsArrayCount, _overlappingSymbols);
        for (uint32_t i=0; i < sectionsCount; ++i ) {
                uint8_t* atoms = _file->_atomsArray + _file->_atomsArrayCount*sizeof(Atom<A>);
                breakIterator2.beginSection();
@@ -1628,6 +1758,7 @@ ld::relocatable::File* Parser<A>::parse(const ParserOptions& opts)
                        _file->_unwindInfos.push_back(info);
                        Atom<A>* func = findAtomByAddress(cfiArray[i].u.fdeInfo.function.targetAddress);
                        func->setUnwindInfoRange(_file->_unwindInfos.size()-1, 1);
+                       //fprintf(stderr, "cu from dwarf =0x%08X, atom=%s\n", info.unwindInfo, func->name());
                }
        }
        // apply compact infos in __LD,__compact_unwind section to each function
@@ -1639,22 +1770,26 @@ ld::relocatable::File* Parser<A>::parse(const ParserOptions& opts)
                assert(info->function != NULL);
                ld::Atom::UnwindInfo ui;
                ui.startOffset = info->functionStartAddress - info->function->objectAddress();
-               ui.unwindInfo = info->compactUnwindInfo;                
+               ui.unwindInfo = info->compactUnwindInfo;
                _file->_unwindInfos.push_back(ui);
-               // if previous is for same function, extend range
-               if ( info->function == lastFunc ) {
-                       if ( lastEnd != ui.startOffset ) {
-                               if ( lastEnd < ui.startOffset )
-                                       warning("__LD,__compact_unwind entries for %s have a gap at offset 0x%0X", info->function->name(), lastEnd);
-                               else
-                                       warning("__LD,__compact_unwind entries for %s overlap at offset 0x%0X", info->function->name(), lastEnd);
+               // don't override with converted cu with "use dwarf" cu, if forcing dwarf conversion
+               if ( !_forceDwarfConversion || !CUSection<A>::encodingMeansUseDwarf(info->compactUnwindInfo) ) {
+                       //fprintf(stderr, "cu=0x%08X, atom=%s\n", ui.unwindInfo, info->function->name());
+                       // if previous is for same function, extend range
+                       if ( info->function == lastFunc ) {
+                               if ( lastEnd != ui.startOffset ) {
+                                       if ( lastEnd < ui.startOffset )
+                                               warning("__LD,__compact_unwind entries for %s have a gap at offset 0x%0X", info->function->name(), lastEnd);
+                                       else
+                                               warning("__LD,__compact_unwind entries for %s overlap at offset 0x%0X", info->function->name(), lastEnd);
+                               }
+                               lastFunc->extendUnwindInfoRange();
                        }
-                       lastFunc->extendUnwindInfoRange();
+                       else 
+                               info->function->setUnwindInfoRange(_file->_unwindInfos.size()-1, 1);
+                       lastFunc = info->function;
+                       lastEnd = ui.startOffset + info->rangeLength;
                }
-               else 
-                       info->function->setUnwindInfoRange(_file->_unwindInfos.size()-1, 1);
-               lastFunc = info->function;
-               lastEnd = ui.startOffset + info->rangeLength;
        }
        
        // parse dwarf debug info to get line info
@@ -1668,6 +1803,7 @@ ld::relocatable::File* Parser<A>::parse(const ParserOptions& opts)
 template <> uint8_t Parser<x86>::loadCommandSizeMask()         { return 0x03; }
 template <> uint8_t Parser<x86_64>::loadCommandSizeMask()      { return 0x07; }
 template <> uint8_t Parser<arm>::loadCommandSizeMask()         { return 0x03; }
+template <> uint8_t Parser<arm64>::loadCommandSizeMask()       { return 0x07; }
 
 template <typename A>
 bool Parser<A>::parseLoadCommands()
@@ -1738,6 +1874,30 @@ bool Parser<A>::parseLoadCommands()
                                        if ( _dataInCodeEnd > (macho_data_in_code_entry<P>*)endOfFile )
                                                throw "LC_DATA_IN_CODE table extends beyond end of file";
                                }
+                               break;
+                       case LC_LINKER_OPTION:
+                               {
+                                       const macho_linker_option_command<P>* loc = (macho_linker_option_command<P>*)cmd;
+                                       const char* buffer = loc->buffer();
+                                       _file->_linkerOptions.resize(_file->_linkerOptions.size() + 1);
+                                       std::vector<const char*>& vec = _file->_linkerOptions.back();
+                                       for (uint32_t j=0; j < loc->count(); ++j) {
+                                               vec.push_back(buffer);
+                                               buffer += strlen(buffer) + 1;
+                                       }
+                                       if ( buffer > ((char*)cmd + loc->cmdsize()) )
+                                               throw "malformed LC_LINKER_OPTION";
+                               }
+                               break;
+                       case LC_LINKER_OPTIMIZATION_HINTS:
+                               {
+                                       const macho_linkedit_data_command<P>* loh = (macho_linkedit_data_command<P>*)cmd;
+                                       _lohStart = _fileContent + loh->dataoff();
+                                       _lohEnd = _fileContent + loh->dataoff() + loh->datasize();
+                                       if ( _lohEnd > endOfFile )
+                                               throw "LC_LINKER_OPTIMIZATION_HINTS table extends beyond end of file";
+                               }
+                               break;
                        default:
                                if ( cmd->cmd() == macho_segment_command<P>::CMD ) {
                                        if ( segment != NULL )
@@ -1984,7 +2144,6 @@ void Parser<A>::makeSortedSymbolsArray(uint32_t array[], const uint32_t sectionA
        }
 }
 
-
 template <typename A>
 void Parser<A>::makeSections()
 {
@@ -2034,6 +2193,7 @@ void Parser<A>::makeSections()
                        //      };
                        // #define OBJC_IMAGE_SUPPORTS_GC   2
                        // #define OBJC_IMAGE_GC_ONLY       4
+                       // #define OBJC_IMAGE_IS_SIMULATED  32
                        //
                        const uint32_t* contents = (uint32_t*)(_file->fileContent()+sect->offset());
                        if ( (sect->size() >= 8) && (contents[0] == 0) ) {
@@ -2042,6 +2202,8 @@ void Parser<A>::makeSections()
                                        _file->_objConstraint = ld::File::objcConstraintGC;
                                else if ( (flags & 2) == 2 )
                                        _file->_objConstraint = ld::File::objcConstraintRetainReleaseOrGC;
+                               else if ( (flags & 32) == 32 )
+                                       _file->_objConstraint = ld::File::objcConstraintRetainReleaseForSimulator;
                                else
                                        _file->_objConstraint = ld::File::objcConstraintRetainRelease;
                                if ( sect->size() > 8 ) {
@@ -2463,8 +2625,14 @@ const char* Parser<A>::scanSymbolTableForAddress(uint64_t addr)
                        continue;
 
                // return with exact match
-               if ( sym.n_value() == addr )
-                       return nameFromSymbol(sym);
+               if ( sym.n_value() == addr ) {
+                       const char* name = nameFromSymbol(sym);
+                       if ( strncmp(name, "ltmp", 4) != 0 ) 
+                               return name;
+                       // treat 'ltmp*' labels as close match
+                       closestSymAddr = sym.n_value();
+                       closestSymName = name;
+               }
                
                // record closest seen so far
                if ( (sym.n_value() < addr) && ((sym.n_value() > closestSymAddr) || (closestSymName == NULL)) )
@@ -2519,6 +2687,29 @@ void Parser<A>::addFixups(const SourceLocation& src, ld::Fixup::Kind setKind, co
                        case ld::Fixup::kindStoreThumbBranch22:
                                firstKind = ld::Fixup::kindStoreTargetAddressThumbBranch22;
                                break;
+#if SUPPORT_ARCH_arm64
+                       case ld::Fixup::kindStoreARM64Branch26:
+                               firstKind = ld::Fixup::kindStoreTargetAddressARM64Branch26;
+                               break;
+                       case ld::Fixup::kindStoreARM64Page21:
+                               firstKind = ld::Fixup::kindStoreTargetAddressARM64Page21;
+                               break;
+                       case ld::Fixup::kindStoreARM64PageOff12:
+                               firstKind = ld::Fixup::kindStoreTargetAddressARM64PageOff12;
+                               break;
+                       case ld::Fixup::kindStoreARM64GOTLoadPage21:
+                               firstKind = ld::Fixup::kindStoreTargetAddressARM64GOTLoadPage21;
+                               break;
+                       case ld::Fixup::kindStoreARM64GOTLoadPageOff12:
+                               firstKind = ld::Fixup::kindStoreTargetAddressARM64GOTLoadPageOff12;
+                               break;
+                       case ld::Fixup::kindStoreARM64TLVPLoadPage21:
+                               firstKind = ld::Fixup::kindStoreTargetAddressARM64TLVPLoadPage21;
+                               break;
+                       case ld::Fixup::kindStoreARM64TLVPLoadPageOff12:
+                               firstKind = ld::Fixup::kindStoreTargetAddressARM64TLVPLoadPageOff12;
+                               break;
+#endif
                        default:
                                combined = false;
                                cl = ld::Fixup::k1of2;
@@ -2537,6 +2728,10 @@ void Parser<A>::addFixups(const SourceLocation& src, ld::Fixup::Kind setKind, co
                        // backing string in CFStrings should always be direct
                        addFixup(src, cl, firstKind, target.atom);
                }
+               else if ( (src.atom == target.atom) && (target.atom->combine() == ld::Atom::combineByName) ) {
+                       // reference to self should always be direct
+                       addFixup(src, cl, firstKind, target.atom);
+               }
                else {
                        // change direct fixup to by-name fixup
                        addFixup(src, cl, firstKind, false, target.atom->name());
@@ -2922,6 +3117,22 @@ bool Parser<A>::skip_form(const uint8_t ** offset, const uint8_t * end, uint64_t
       sz = 4;
       break;
 
+       case DW_FORM_sec_offset:
+         sz = sizeof(typename A::P::uint_t);
+      break;
+       
+       case DW_FORM_exprloc:
+      sz = read_uleb128 (offset, end);
+      break;
+
+    case DW_FORM_flag_present:
+         sz = 0;
+         break;
+         
+    case DW_FORM_ref_sig8:
+         sz = 8;
+         break;
+
     default:
       return false;
     }
@@ -3402,7 +3613,7 @@ bool Parser<A>::read_comp_unit(const char ** name, const char ** comp_dir,
                return false;
 
        vers = A::P::E::get16(*(uint16_t*)di);
-       if (vers < 2 || vers > 3)
+       if (vers < 2 || vers > 4)
        /* DWARF version wrong for this code.
           Chances are we could continue anyway, but we don't know for sure.  */
                return false;
@@ -3695,7 +3906,10 @@ template <typename A>
 ld::Atom::Alignment Section<A>::alignmentForAddress(pint_t addr) 
 { 
        const uint32_t sectionAlignment = this->_machOSection->align();
-       return ld::Atom::Alignment(sectionAlignment, (addr % (1 << sectionAlignment)));
+       uint32_t modulus = (addr % (1 << sectionAlignment));
+       if ( modulus > 0xFFFF )
+               warning("alignment for symbol at address 0x%08llX in %s exceeds 2^16", (uint64_t)addr, this->file().path());
+       return ld::Atom::Alignment(sectionAlignment, modulus);
 }
 
 template <typename A>
@@ -3723,7 +3937,7 @@ template <typename A>
 void CFISection<A>::warnFunc(void* ref, uint64_t funcAddr, const char* msg)
 {
        Parser<A>* parser = (Parser<A>*)ref;
-       if ( ! parser->convertUnwindInfo() ) 
+       if ( ! parser->warnUnwindConversionProblems() ) 
                return;
        if ( funcAddr != CFI_INVALID_ADDRESS ) {
                // atoms are not constructed yet, so scan symbol table for labels
@@ -3741,6 +3955,12 @@ bool CFISection<x86_64>::needsRelocating()
        return true;
 }
 
+template <>
+bool CFISection<arm64>::needsRelocating()
+{
+       return true;
+}
+
 template <typename A>
 bool CFISection<A>::needsRelocating()
 {
@@ -3748,9 +3968,9 @@ bool CFISection<A>::needsRelocating()
 }
 
 template <>
-void CFISection<x86_64>::cfiParse(class Parser<x86_64>& parser, uint8_t* buffer, 
+void CFISection<x86_64>::cfiParse(class Parser<x86_64>& parser, uint8_t* buffer,
                                                                        libunwind::CFI_Atom_Info<CFISection<x86_64>::OAS>::CFI_Atom_Info cfiArray[], 
-                                                                       uint32_t count)
+                                                                       uint32_t& count, const pint_t cuStarts[], uint32_t cuCount)
 {
        // copy __eh_frame data to buffer
        memcpy(buffer, file().fileContent() + this->_machOSection->offset(), this->_machOSection->size());
@@ -3796,7 +4016,6 @@ void CFISection<x86_64>::cfiParse(class Parser<x86_64>& parser, uint8_t* buffer,
                }
        }
        
-       
        // create ObjectAddressSpace object for use by libunwind
        OAS oas(*this, buffer);
        
@@ -3804,6 +4023,7 @@ void CFISection<x86_64>::cfiParse(class Parser<x86_64>& parser, uint8_t* buffer,
        const char* msg;
        msg = libunwind::DwarfInstructions<OAS, libunwind::Registers_x86_64>::parseCFIs(
                                                        oas, this->_machOSection->addr(), this->_machOSection->size(), 
+                                                       cuStarts, cuCount, parser.keepDwarfUnwind(), parser.forceDwarfConversion(), parser.neverConvertDwarf(), 
                                                        cfiArray, count, (void*)&parser, warnFunc);
        if ( msg != NULL ) 
                throwf("malformed __eh_frame section: %s", msg);
@@ -3812,7 +4032,7 @@ void CFISection<x86_64>::cfiParse(class Parser<x86_64>& parser, uint8_t* buffer,
 template <>
 void CFISection<x86>::cfiParse(class Parser<x86>& parser, uint8_t* buffer, 
                                                                        libunwind::CFI_Atom_Info<CFISection<x86>::OAS>::CFI_Atom_Info cfiArray[], 
-                                                                       uint32_t count)
+                                                                       uint32_t& count, const pint_t cuStarts[], uint32_t cuCount)
 {
        // create ObjectAddressSpace object for use by libunwind
        OAS oas(*this, (uint8_t*)this->file().fileContent()+this->_machOSection->offset());
@@ -3821,6 +4041,7 @@ void CFISection<x86>::cfiParse(class Parser<x86>& parser, uint8_t* buffer,
        const char* msg;
        msg = libunwind::DwarfInstructions<OAS, libunwind::Registers_x86>::parseCFIs(
                                                        oas, this->_machOSection->addr(), this->_machOSection->size(), 
+                                                       cuStarts, cuCount, parser.keepDwarfUnwind(), parser.forceDwarfConversion(), parser.neverConvertDwarf(),
                                                        cfiArray, count, (void*)&parser, warnFunc);
        if ( msg != NULL ) 
                throwf("malformed __eh_frame section: %s", msg);
@@ -3832,12 +4053,76 @@ void CFISection<x86>::cfiParse(class Parser<x86>& parser, uint8_t* buffer,
 template <>
 void CFISection<arm>::cfiParse(class Parser<arm>& parser, uint8_t* buffer, 
                                                                        libunwind::CFI_Atom_Info<CFISection<arm>::OAS>::CFI_Atom_Info cfiArray[], 
-                                                                       uint32_t count)
+                                                                       uint32_t& count, const pint_t cuStarts[], uint32_t cuCount)
 {
        // arm does not use zero cost exceptions
        assert(count == 0);
 }
 
+template <>
+void CFISection<arm64>::cfiParse(class Parser<arm64>& parser, uint8_t* buffer, 
+                                                                       libunwind::CFI_Atom_Info<CFISection<arm64>::OAS>::CFI_Atom_Info cfiArray[], 
+                                                                       uint32_t& count, const pint_t cuStarts[], uint32_t cuCount)
+{
+       // copy __eh_frame data to buffer
+       memcpy(buffer, file().fileContent() + this->_machOSection->offset(), this->_machOSection->size());
+
+       // and apply relocations
+       const macho_relocation_info<P>* relocs = (macho_relocation_info<P>*)(file().fileContent() + this->_machOSection->reloff());
+       const macho_relocation_info<P>* relocsEnd = &relocs[this->_machOSection->nreloc()];
+       for (const macho_relocation_info<P>* reloc = relocs; reloc < relocsEnd; ++reloc) {
+               uint64_t* p64 = (uint64_t*)&buffer[reloc->r_address()];
+               uint32_t* p32 = (uint32_t*)&buffer[reloc->r_address()];
+               uint32_t addend32 = E::get32(*p32); 
+               uint64_t addend64 = E::get64(*p64); 
+               uint64_t value = 0;
+               switch ( reloc->r_type() ) {
+                       case ARM64_RELOC_SUBTRACTOR:    
+                               value =  0 - parser.symbolFromIndex(reloc->r_symbolnum()).n_value();
+                               ++reloc;
+                               if ( reloc->r_extern() )
+                                       value += parser.symbolFromIndex(reloc->r_symbolnum()).n_value();
+                               break;
+                       case ARM64_RELOC_UNSIGNED:
+                               value = parser.symbolFromIndex(reloc->r_symbolnum()).n_value();
+                               break;
+                       case ARM64_RELOC_POINTER_TO_GOT:
+                               // this is used for the reference to the personality function in CIEs
+                               // store the symbol number of the personality function for later use as a Fixup
+                               value = reloc->r_symbolnum();
+                               addend32 = 0;
+                               addend64 = 0;
+                               break;
+                       default:
+                               fprintf(stderr, "CFISection::cfiParse() unexpected relocation type at r_address=0x%08X\n", reloc->r_address());
+                               break;
+               }
+               switch ( reloc->r_length() ) {
+                       case 3:
+                               E::set64(*p64, value + addend64);
+                               break;
+                       case 2:
+                               E::set32(*p32, value + addend32);
+                               break;
+                       default:
+                               fprintf(stderr, "CFISection::cfiParse() unexpected relocation size at r_address=0x%08X\n", reloc->r_address());
+                               break;
+               }
+       }
+       
+       
+       // create ObjectAddressSpace object for use by libunwind
+       OAS oas(*this, buffer);
+       
+       // use libuwind to parse __eh_frame data into array of CFI_Atom_Info
+       const char* msg;
+       msg = libunwind::DwarfInstructions<OAS, libunwind::Registers_arm64>::parseCFIs(
+                                                       oas, this->_machOSection->addr(), this->_machOSection->size(), 
+                                                       cuStarts, cuCount, parser.keepDwarfUnwind(), parser.forceDwarfConversion(), parser.neverConvertDwarf(),
+                                                       cfiArray, count, (void*)&parser, warnFunc);
+       if ( msg != NULL ) 
+               throwf("malformed __eh_frame section: %s", msg);
+}
 
 
 template <typename A>
@@ -3875,6 +4160,7 @@ uint32_t CFISection<A>::appendAtoms(class Parser<A>& parser, uint8_t* p,
 template <> bool CFISection<x86_64>::bigEndian() { return false; }
 template <> bool CFISection<x86>::bigEndian() { return false; }
 template <> bool CFISection<arm>::bigEndian() { return false; }
+template <> bool CFISection<arm64>::bigEndian() { return false; }
 
 
 template <>
@@ -3924,11 +4210,36 @@ void CFISection<x86>::addCiePersonalityFixups(class Parser<x86>& parser, const C
 }
 
 
+
+#if SUPPORT_ARCH_arm64
+template <>
+void CFISection<arm64>::addCiePersonalityFixups(class Parser<arm64>& parser, const CFI_Atom_Info* cieInfo)
+{
+       uint8_t personalityEncoding = cieInfo->u.cieInfo.personality.encodingOfTargetAddress;
+       if ( personalityEncoding == 0x9B ) {
+               // compiler always produces ARM64_RELOC_GOT r_pcrel=1 to personality function
+               // CFISection<arm64>::cfiParse() set targetAddress to be symbolIndex + addressInCIE
+               uint32_t symbolIndex = cieInfo->u.cieInfo.personality.targetAddress 
+                                                                       - cieInfo->address - cieInfo->u.cieInfo.personality.offsetInCFI;
+               const macho_nlist<P>& sym = parser.symbolFromIndex(symbolIndex);
+               const char* personalityName = parser.nameFromSymbol(sym);
+
+               Atom<arm64>* cieAtom = this->findAtomByAddress(cieInfo->address);
+               Parser<arm64>::SourceLocation src(cieAtom, cieInfo->u.cieInfo.personality.offsetInCFI);
+               parser.addFixup(src, ld::Fixup::k1of2, ld::Fixup::kindSetTargetAddress, false, personalityName);
+               parser.addFixup(src, ld::Fixup::k2of2, ld::Fixup::kindStoreARM64PCRelToGOT);
+       }
+       else if ( personalityEncoding != 0 ) {
+               throwf("unsupported address encoding (%02X) of personality function in CIE", 
+                               personalityEncoding);
+       }
+}
+#endif
+
 template <typename A>
 void CFISection<A>::addCiePersonalityFixups(class Parser<A>& parser, const CFI_Atom_Info* cieInfo)
 {
-       // FIX ME
-       assert(0);
+       assert(0 && "addCiePersonalityFixups() not implemented for arch");
 }
 
 template <typename A>
@@ -4162,27 +4473,103 @@ typename A::P::uint_t CFISection<A>::OAS::getEncodedP(pint_t& addr, pint_t end,
 template <>
 const char* CUSection<x86_64>::personalityName(class Parser<x86_64>& parser, const macho_relocation_info<x86_64::P>* reloc)
 {
-       assert(reloc->r_extern() && "reloc not extern on personality column in __compact_unwind section");
-       assert((reloc->r_type() == X86_64_RELOC_UNSIGNED) && "wrong reloc type on personality column in __compact_unwind section");
-       const macho_nlist<P>& sym = parser.symbolFromIndex(reloc->r_symbolnum());
-       return parser.nameFromSymbol(sym);
+       if ( reloc->r_extern() ) {
+               assert((reloc->r_type() == X86_64_RELOC_UNSIGNED) && "wrong reloc type on personality column in __compact_unwind section");
+               const macho_nlist<P>& sym = parser.symbolFromIndex(reloc->r_symbolnum());
+               return parser.nameFromSymbol(sym);
+       }
+       else {
+               const pint_t* content = (pint_t*)(this->file().fileContent() + this->_machOSection->offset() + reloc->r_address());
+               pint_t personalityAddr = *content;
+               Section<x86_64>* personalitySection = parser.sectionForAddress(personalityAddr);
+               assert((personalitySection->type() == ld::Section::typeCode) && "personality column in __compact_unwind section is not pointer to function");
+               // atoms may not be constructed yet, so scan symbol table for labels
+               const char* name = parser.scanSymbolTableForAddress(personalityAddr);
+               return name;
+       }
 }
 
 template <>
 const char* CUSection<x86>::personalityName(class Parser<x86>& parser, const macho_relocation_info<x86::P>* reloc)
 {
-       assert(reloc->r_extern() && "reloc not extern on personality column in __compact_unwind section");
-       assert((reloc->r_type() == GENERIC_RELOC_VANILLA) && "wrong reloc type on personality column in __compact_unwind section");
-       const macho_nlist<P>& sym = parser.symbolFromIndex(reloc->r_symbolnum());
-       return parser.nameFromSymbol(sym);
+       if ( reloc->r_extern() ) {
+               assert((reloc->r_type() == GENERIC_RELOC_VANILLA) && "wrong reloc type on personality column in __compact_unwind section");
+               const macho_nlist<P>& sym = parser.symbolFromIndex(reloc->r_symbolnum());
+               return parser.nameFromSymbol(sym);
+       }
+       else {
+               // support __LD, __compact_unwind personality entries which are pointer to personality non-lazy pointer
+               const pint_t* content = (pint_t*)(this->file().fileContent() + this->_machOSection->offset() + reloc->r_address());
+               pint_t nlPointerAddr = *content;
+               Section<x86>* nlSection = parser.sectionForAddress(nlPointerAddr);
+               if ( nlSection->type() == ld::Section::typeCode ) {
+                       // personality function is defined in this .o file, so this is a direct reference to it
+                       // atoms may not be constructed yet, so scan symbol table for labels
+                       const char* name = parser.scanSymbolTableForAddress(nlPointerAddr);
+                       return name;
+               }
+               else {
+                       uint32_t symIndex = parser.symbolIndexFromIndirectSectionAddress(nlPointerAddr, nlSection->machoSection());
+                       const macho_nlist<P>& nlSymbol = parser.symbolFromIndex(symIndex);
+                       return parser.nameFromSymbol(nlSymbol);
+               }
+       }
 }
 
+#if SUPPORT_ARCH_arm64
+template <>
+const char* CUSection<arm64>::personalityName(class Parser<arm64>& parser, const macho_relocation_info<arm64::P>* reloc)
+{
+       if ( reloc->r_extern() ) {
+               assert((reloc->r_type() == ARM64_RELOC_UNSIGNED) && "wrong reloc type on personality column in __compact_unwind section");
+               const macho_nlist<P>& sym = parser.symbolFromIndex(reloc->r_symbolnum());
+               return parser.nameFromSymbol(sym);
+       }
+       else {
+               const pint_t* content = (pint_t*)(this->file().fileContent() + this->_machOSection->offset() + reloc->r_address());
+               pint_t personalityAddr = *content;
+               Section<arm64>* personalitySection = parser.sectionForAddress(personalityAddr);
+               assert((personalitySection->type() == ld::Section::typeCode) && "personality column in __compact_unwind section is not pointer to function");
+               // atoms may not be constructed yet, so scan symbol table for labels
+               const char* name = parser.scanSymbolTableForAddress(personalityAddr);
+               return name;
+       }
+}
+#endif
+
 template <typename A>
 const char* CUSection<A>::personalityName(class Parser<A>& parser, const macho_relocation_info<P>* reloc)
 {
        return NULL;
 }
 
+template <>
+bool CUSection<x86>::encodingMeansUseDwarf(compact_unwind_encoding_t enc)
+{
+       return ((enc & UNWIND_X86_MODE_MASK) == UNWIND_X86_MODE_DWARF);
+}
+
+template <>
+bool CUSection<x86_64>::encodingMeansUseDwarf(compact_unwind_encoding_t enc)
+{
+       return ((enc & UNWIND_X86_64_MODE_MASK) == UNWIND_X86_64_MODE_DWARF);
+}
+
+#if SUPPORT_ARCH_arm_any
+template <>
+bool CUSection<arm>::encodingMeansUseDwarf(compact_unwind_encoding_t enc)
+{
+       return false;
+}
+#endif
+
+#if SUPPORT_ARCH_arm64
+template <>
+bool CUSection<arm64>::encodingMeansUseDwarf(compact_unwind_encoding_t enc)
+{
+       return ((enc & UNWIND_ARM64_MODE_MASK) == UNWIND_ARM64_MODE_DWARF);
+}
+#endif
 
 template <typename A>
 int CUSection<A>::infoSorter(const void* l, const void* r)
@@ -4219,8 +4606,7 @@ void CUSection<A>::parse(class Parser<A>& parser, uint32_t cnt, Info array[])
                }
        }
        
-       // scan relocs, local relocs are useless - ignore them
-       // extern relocs are needed for personality references (possibly for function/lsda refs??)
+       // scan relocs, extern relocs are needed for personality references (possibly for function/lsda refs??)
        const macho_relocation_info<P>* relocs = (macho_relocation_info<P>*)(this->file().fileContent() + this->_machOSection->reloff());
        const macho_relocation_info<P>* relocsEnd = &relocs[this->_machOSection->nreloc()];
        for (const macho_relocation_info<P>* reloc = relocs; reloc < relocsEnd; ++reloc) {
@@ -4241,11 +4627,18 @@ void CUSection<A>::parse(class Parser<A>& parser, uint32_t cnt, Info array[])
                        else if ( (reloc->r_address() % sizeof(macho_compact_unwind_entry<P>)) == macho_compact_unwind_entry<P>::codeStartFieldOffset() ) {
                                uint32_t entryIndex = reloc->r_address() / sizeof(macho_compact_unwind_entry<P>);
                                array[entryIndex].functionSymbolIndex = reloc->r_symbolnum();
+                               array[entryIndex].functionStartAddress += parser.symbolFromIndex(reloc->r_symbolnum()).n_value();
                        }
                        else {
                                warning("unexpected extern relocation in __compact_unwind section");
                        }
                }
+               else {
+                       if ( (reloc->r_address() % sizeof(macho_compact_unwind_entry<P>)) == macho_compact_unwind_entry<P>::personalityFieldOffset() ) {
+                               uint32_t entryIndex = reloc->r_address() / sizeof(macho_compact_unwind_entry<P>);
+                               array[entryIndex].personality = this->personalityName(parser, reloc);
+                       }
+               }
        }
        
        // sort array by function start address so unwind infos will be contiguous for a given function
@@ -4268,9 +4661,6 @@ void CUSection<A>::makeFixups(class Parser<A>& parser, const struct Parser<A>::C
        Info* const arrayStart = cus.cuArray;
        Info* const arrayEnd = &cus.cuArray[cus.cuCount];
        for (Info* info=arrayStart; info < arrayEnd; ++info) {
-               // if external reloc was used, real address is symbol n_value + addend
-               if ( info->functionSymbolIndex != 0xFFFFFFFF )
-                       info->functionStartAddress += parser.symbolFromIndex(info->functionSymbolIndex).n_value();
                // find function atom from address
                info->function = parser.findAtomByAddress(info->functionStartAddress);  
                // find lsda atom from address
@@ -4356,7 +4746,7 @@ uint32_t SymboledSection<A>::computeAtomCount(class Parser<A>& parser,
        pint_t  addr;
        pint_t  size;
        const macho_nlist<P>* sym;
-       while ( it.next(parser, sectNum, startAddr, endAddr, &addr, &size, &sym) ) {
+       while ( it.next(parser, *this, sectNum, startAddr, endAddr, &addr, &size, &sym) ) {
                ++count;
        }
        //fprintf(stderr, "computeAtomCount(%s,%s) => %d\n", this->segmentName(), this->sectionName(), count);
@@ -4365,7 +4755,7 @@ uint32_t SymboledSection<A>::computeAtomCount(class Parser<A>& parser,
 
 template <typename A>
 uint32_t SymboledSection<A>::appendAtoms(class Parser<A>& parser, uint8_t* p, 
-                                                                                       struct Parser<A>::LabelAndCFIBreakIterator& it, 
+                                                                                       struct Parser<A>::LabelAndCFIBreakIterator& it,
                                                                                        const struct Parser<A>::CFI_CU_InfoArrays&)
 {
        this->_beginAtoms = (Atom<A>*)p;
@@ -4379,7 +4769,7 @@ uint32_t SymboledSection<A>::appendAtoms(class Parser<A>& parser, uint8_t* p,
        pint_t  addr;
        pint_t  size;
        const macho_nlist<P>* label;
-       while ( it.next(parser, sectNum, startAddr, endAddr, &addr, &size, &label) ) {
+       while ( it.next(parser, *this, sectNum, startAddr, endAddr, &addr, &size, &label) ) {
                Atom<A>* allocatedSpace = (Atom<A>*)p;
                // is break because of label or CFI?
                if ( label != NULL ) {
@@ -4396,7 +4786,7 @@ uint32_t SymboledSection<A>::appendAtoms(class Parser<A>& parser, uint8_t* p,
                        ld::Atom::ContentType ctype = this->contentType();
                        if ( ctype == ld::Atom::typeLSDA )
                                inclusion = ld::Atom::symbolTableInWithRandomAutoStripLabel;
-                       new (allocatedSpace) Atom<A>(*this, "anon", addr, size, ld::Atom::definitionRegular, ld::Atom::combineNever, 
+                       new (allocatedSpace) Atom<A>(*this, "anon", addr, size, ld::Atom::definitionRegular, ld::Atom::combineNever,
                                                                                ld::Atom::scopeTranslationUnit, ctype, inclusion, 
                                                                                this->dontDeadStrip(), false, false, this->alignmentForAddress(addr));
                }
@@ -4409,6 +4799,19 @@ uint32_t SymboledSection<A>::appendAtoms(class Parser<A>& parser, uint8_t* p,
 }
 
 
+template <>
+ld::Atom::SymbolTableInclusion ImplicitSizeSection<arm64>::symbolTableInclusion()
+{
+       return ld::Atom::symbolTableInWithRandomAutoStripLabel;
+}
+
+template <typename A>
+ld::Atom::SymbolTableInclusion ImplicitSizeSection<A>::symbolTableInclusion()
+{
+       return ld::Atom::symbolTableNotIn;
+}
+
+
 template <typename A>
 uint32_t ImplicitSizeSection<A>::computeAtomCount(class Parser<A>& parser, 
                                                                                                        struct Parser<A>::LabelAndCFIBreakIterator& it, 
@@ -4426,15 +4829,18 @@ uint32_t ImplicitSizeSection<A>::computeAtomCount(class Parser<A>& parser,
                // if there are multiple labels in this section for the same address, then clone them into multi atoms
                pint_t  prevSymbolAddr = (pint_t)(-1);
                uint8_t prevSymbolSectNum = 0;
+               bool prevIgnore = false;
                for(uint32_t i=0; i < it.sortedSymbolCount; ++i) {
                        const macho_nlist<P>& sym = parser.symbolFromIndex(it.sortedSymbolIndexes[i]);
                        const pint_t symbolAddr = sym.n_value();
-                       const pint_t symbolSectNum = sym.n_sect();
-                       if ( (symbolAddr == prevSymbolAddr) && (prevSymbolSectNum == symbolSectNum) && (symbolSectNum == this->sectionNum(parser)) ) { 
+                       const uint8_t symbolSectNum = sym.n_sect();
+                       const bool ignore = this->ignoreLabel(parser.nameFromSymbol(sym));
+                       if ( !ignore && !prevIgnore && (symbolAddr == prevSymbolAddr) && (prevSymbolSectNum == symbolSectNum) && (symbolSectNum == this->sectionNum(parser)) ) { 
                                ++count;
                        }
                        prevSymbolAddr = symbolAddr;
                        prevSymbolSectNum = symbolSectNum;
+                       prevIgnore = ignore;
                }
        }
        return count;
@@ -4457,33 +4863,44 @@ uint32_t ImplicitSizeSection<A>::appendAtoms(class Parser<A>& parser, uint8_t* p
        pint_t  size;
        const macho_nlist<P>* foundLabel;
        Atom<A>* allocatedSpace;
-       while ( it.next(parser, sectNum, startAddr, endAddr, &foundAddr, &size, &foundLabel) ) {
+       while ( it.next(parser, *this, sectNum, startAddr, endAddr, &foundAddr, &size, &foundLabel) ) {
                if ( foundLabel != NULL ) {
+                       bool skip = false;
                        pint_t labeledAtomSize = this->elementSizeAtAddress(foundAddr);
                        allocatedSpace = (Atom<A>*)p;
                        if ( this->ignoreLabel(parser.nameFromSymbol(*foundLabel)) ) {
-                               //fprintf(stderr, "  0x%08llX make annon\n", (uint64_t)foundAddr);
-                               new (allocatedSpace) Atom<A>(*this, this->unlabeledAtomName(parser, foundAddr), foundAddr, 
+                               if ( size == 0 ) {
+                                       // <rdar://problem/10018737> 
+                                       // a size of zero means there is another label at same location 
+                                       // and we are supposed to ignore this label
+                                       skip = true;
+                               }
+                               else {
+                                       //fprintf(stderr, "  0x%08llX make annon, size=%lld\n", (uint64_t)foundAddr, (uint64_t)size);
+                                       new (allocatedSpace) Atom<A>(*this, this->unlabeledAtomName(parser, foundAddr), foundAddr, 
                                                                                        this->elementSizeAtAddress(foundAddr), this->definition(), 
                                                                                        this->combine(parser, foundAddr), this->scopeAtAddress(parser, foundAddr), 
                                                                                        this->contentType(), this->symbolTableInclusion(), 
                                                                                        this->dontDeadStrip(), false, false, this->alignmentForAddress(foundAddr));
+                               }
                        }
                        else {
                                // make named atom for label
                                //fprintf(stderr, "  0x%08llX make labeled\n", (uint64_t)foundAddr);
                                new (allocatedSpace) Atom<A>(*this, parser, *foundLabel, labeledAtomSize);
                        }
-                       ++count;
-                       p += sizeof(Atom<A>);
-                       foundAddr += labeledAtomSize;
-                       size -= labeledAtomSize;
+                       if ( !skip ) {
+                               ++count;
+                               p += sizeof(Atom<A>);
+                               foundAddr += labeledAtomSize;
+                               size -= labeledAtomSize;
+                       }
                }
                // some number of anonymous atoms
                for (pint_t addr = foundAddr; addr < (foundAddr+size); addr += elementSizeAtAddress(addr) ) {
                        // make anon atoms for area before label
                        if ( this->useElementAt(parser, it, addr) ) {
-                               //fprintf(stderr, "  0x%08llX make annon\n", (uint64_t)addr);
+                               //fprintf(stderr, "  0x%08llX make annon, size=%lld\n", (uint64_t)addr, (uint64_t)elementSizeAtAddress(addr));
                                allocatedSpace = (Atom<A>*)p;
                                new (allocatedSpace) Atom<A>(*this, this->unlabeledAtomName(parser, addr), addr, this->elementSizeAtAddress(addr), 
                                                                                        this->definition(), this->combine(parser, addr), this->scopeAtAddress(parser, addr), 
@@ -4606,11 +5023,12 @@ bool CStringSection<A>::useElementAt(Parser<A>& parser, struct Parser<A>::LabelA
 }
 
 template <typename A>
-bool CStringSection<A>::ignoreLabel(const char* label)  
+bool CStringSection<A>::ignoreLabel(const char* label) const
 { 
        return (label[0] == 'L') || (label[0] == 'l'); 
 }
 
+
 template <typename A>
 Atom<A>* CStringSection<A>::findAtomByAddress(pint_t addr)
 {
@@ -4665,6 +5083,12 @@ ld::Fixup::Kind NonLazyPointerSection<arm>::fixupKind()
        return ld::Fixup::kindStoreLittleEndian32;
 }
 
+template <>
+ld::Fixup::Kind NonLazyPointerSection<arm64>::fixupKind()
+{
+       return ld::Fixup::kindStoreLittleEndian64;
+}
+
 
 template <>
 void NonLazyPointerSection<x86_64>::makeFixups(class Parser<x86_64>& parser, const struct Parser<x86_64>::CFI_CU_InfoArrays&)
@@ -4832,7 +5256,11 @@ const uint8_t* CFStringSection<A>::targetContent(const class Atom<A>* atom, cons
                        *ct = contentUTF16;
                        *count = (targetAtom->size()+1)/2; // round up incase of buggy compiler that has only one trailing zero byte
                }
-               assert(target !=  NULL);
+               else {
+                       *ct = contentUnknown;
+                       *count = 0;
+                       return NULL;
+               }
                return target->contentPointer();
        }
        assert(0);
@@ -4862,7 +5290,8 @@ unsigned long CFStringSection<A>::contentHash(const class Atom<A>* atom, const l
                        }
                        return hash;
                case contentUnknown:
-                       return 0;
+                       // <rdar://problem/14134211> For malformed CFStrings, hash to address of atom so they have unique hashes
+                       return ULONG_MAX - (unsigned long)(atom);
        }
        return 0;
 }
@@ -4891,6 +5320,12 @@ bool CFStringSection<A>::canCoalesceWith(const class Atom<A>* atom, const ld::At
        if ( thisType != rhsType )
                return false;
 
+       if ( thisType == contentUnknown )
+               return false;
+
+       if ( rhsType == contentUnknown )
+               return false;
+
        // no need to compare content of pointers are already the same
        if ( cstringContent == rhsStringContent ) 
                return true;
@@ -5056,12 +5491,16 @@ const char* PointerToCStringSection<A>::targetCString(const class Atom<A>* atom,
                case ld::Fixup::bindingsIndirectlyBound:
                        targetAtom = ind.indirectAtom(fit->u.bindingIndex);
                        break;
+               case ld::Fixup::bindingDirectlyBound:
+                       targetAtom = fit->u.target;
+                       break;
                default:
-                       assert(0);
+                       assert(0 && "unsupported reference to selector");
        }
        assert(targetAtom != NULL);
        const Atom<A>* target = dynamic_cast<const Atom<A>*>(targetAtom);
-       assert(target !=  NULL);
+       assert(target != NULL);
+       assert(target->contentType() == ld::Atom::typeCString);
        return (char*)target->contentPointer();
 }
 
@@ -6054,8 +6493,314 @@ bool Section<arm>::addRelocFixup(class Parser<arm>& parser, const macho_relocati
 #endif
 
 
-
-
+#if SUPPORT_ARCH_arm64
+template <>
+bool Section<arm64>::addRelocFixup(class Parser<arm64>& parser, const macho_relocation_info<P>* reloc)
+{
+       bool result = false;
+       Parser<arm64>::SourceLocation   src;
+       Parser<arm64>::TargetDesc               target = { NULL, NULL, false, 0 };
+       Parser<arm64>::TargetDesc               toTarget;
+       int32_t prefixRelocAddend = 0;
+       if ( reloc->r_type() == ARM64_RELOC_ADDEND ) {
+               uint32_t rawAddend = reloc->r_symbolnum(); 
+               prefixRelocAddend = rawAddend;
+               if ( rawAddend & 0x00800000 )
+                       prefixRelocAddend |= 0xFF000000; // sign extend 24-bit signed int to 32-bits
+               uint32_t addendAddress = reloc->r_address();
+               ++reloc;  //advance to next reloc record
+               result = true;
+               if ( reloc->r_address() != addendAddress )
+                       throw "ARM64_RELOC_ADDEND r_address does not match next reloc's r_address";
+       }
+       const macho_section<P>* sect = this->machoSection();
+       uint64_t srcAddr = sect->addr() + reloc->r_address();
+       src.atom = this->findAtomByAddress(srcAddr);
+       src.offsetInAtom = srcAddr - src.atom->_objAddress;
+       const uint8_t* fixUpPtr = file().fileContent() + sect->offset() + reloc->r_address();
+       uint64_t contentValue = 0;
+       const macho_relocation_info<arm64::P>* nextReloc = &reloc[1];
+       bool useDirectBinding;
+       uint32_t instruction;
+       uint32_t encodedAddend;
+       switch ( reloc->r_length() ) {
+               case 0:
+                       contentValue = *fixUpPtr;
+                       break;
+               case 1:
+                       contentValue = (int64_t)(int16_t)E::get16(*((uint16_t*)fixUpPtr));
+                       break;
+               case 2:
+                       contentValue = (int64_t)(int32_t)E::get32(*((uint32_t*)fixUpPtr));
+                       break;
+               case 3:
+                       contentValue = E::get64(*((uint64_t*)fixUpPtr));
+                       break;
+       }
+       if ( reloc->r_extern() ) {
+               const macho_nlist<P>& sym = parser.symbolFromIndex(reloc->r_symbolnum());
+               const char* symbolName = parser.nameFromSymbol(sym);
+               if ( ((sym.n_type() & N_TYPE) == N_SECT) && (((sym.n_type() & N_EXT) == 0) || (symbolName[0] == 'L') || (symbolName[0] == 'l')) ) {
+                       // use direct reference for local symbols
+                       parser.findTargetFromAddressAndSectionNum(sym.n_value(), sym.n_sect(), target);
+                       //target.addend += contentValue;
+               }
+               else if ( ((sym.n_type() & N_TYPE) == N_SECT) && (src.atom->_objAddress <= sym.n_value()) && (sym.n_value() < (src.atom->_objAddress+src.atom->size())) ) {
+                       // <rdar://problem/13700961> spurious warning when weak function has reference to itself
+                       // use direct reference when atom targets itself
+                       target.atom = src.atom;
+                       target.name = NULL;
+               }
+               else {
+                       target.name = symbolName;
+                       target.weakImport = parser.weakImportFromSymbol(sym);
+                       //target.addend = contentValue;
+               }
+               // cfstrings should always use direct reference to backing store
+               if ( (this->type() == ld::Section::typeCFString) && (src.offsetInAtom != 0) ) {
+                       parser.findTargetFromAddressAndSectionNum(sym.n_value(), sym.n_sect(), target);
+                       //target.addend = contentValue;
+               }
+       }
+       else {
+               if ( reloc->r_pcrel()  )
+                       contentValue += srcAddr;
+               parser.findTargetFromAddressAndSectionNum(contentValue, reloc->r_symbolnum(), target);
+       }
+       switch ( reloc->r_type() ) {
+               case ARM64_RELOC_UNSIGNED:
+                       if ( reloc->r_pcrel() )
+                               throw "pcrel and ARM64_RELOC_UNSIGNED not supported";
+                       target.addend = contentValue;
+                       switch ( reloc->r_length() ) {
+                               case 0:
+                               case 1:
+                                       throw "length < 2 and ARM64_RELOC_UNSIGNED not supported";
+                               case 2:
+                                       parser.addFixups(src, ld::Fixup::kindStoreLittleEndian32, target);
+                                       break;
+                               case 3:
+                                       parser.addFixups(src, ld::Fixup::kindStoreLittleEndian64, target);
+                                       break;
+                       }
+                       break;
+               case ARM64_RELOC_BRANCH26:
+                       if ( ! reloc->r_pcrel() )
+                               throw "not pcrel and ARM64_RELOC_BRANCH26 not supported";
+                       if ( ! reloc->r_extern() ) 
+                               throw "r_extern == 0 and ARM64_RELOC_BRANCH26 not supported";
+                       if ( reloc->r_length() != 2 )
+                               throw "r_length != 2 and ARM64_RELOC_BRANCH26 not supported";
+                       if ( (target.name != NULL) && (strncmp(target.name, "___dtrace_probe$", 16) == 0) ) {
+                               parser.addFixup(src, ld::Fixup::k1of1, ld::Fixup::kindStoreARM64DtraceCallSiteNop, false, target.name);
+                               parser.addDtraceExtraInfos(src, &target.name[16]);
+                       }
+                       else if ( (target.name != NULL) && (strncmp(target.name, "___dtrace_isenabled$", 20) == 0) ) {
+                               parser.addFixup(src, ld::Fixup::k1of1, ld::Fixup::kindStoreARM64DtraceIsEnableSiteClear, false, target.name);
+                               parser.addDtraceExtraInfos(src, &target.name[20]);
+                       }
+                       else {
+                               target.addend = prefixRelocAddend;
+                               instruction = contentValue;
+                               encodedAddend = (instruction & 0x03FFFFFF) << 2;
+                               if ( encodedAddend != 0 ) {
+                                       if ( prefixRelocAddend == 0 ) {
+                                               warning("branch26 instruction at 0x%08X has embedded addend. ARM64_RELOC_ADDEND should be used instead", reloc->r_address());
+                                               target.addend = encodedAddend;
+                                       }
+                                       else {
+                                               throwf("branch26 instruction at 0x%08X has embedded addend and ARM64_RELOC_ADDEND also used", reloc->r_address());
+                                       }
+                               }
+                               parser.addFixups(src, ld::Fixup::kindStoreARM64Branch26, target);
+                       }
+                       break;
+               case ARM64_RELOC_PAGE21:
+                       if ( ! reloc->r_pcrel() )
+                               throw "not pcrel and ARM64_RELOC_PAGE21 not supported";
+                       if ( ! reloc->r_extern() ) 
+                               throw "r_extern == 0 and ARM64_RELOC_PAGE21 not supported";
+                       if ( reloc->r_length() != 2 ) 
+                               throw "length != 2 and ARM64_RELOC_PAGE21 not supported";
+                       target.addend = prefixRelocAddend;
+                       instruction = contentValue;
+                       encodedAddend  = ((instruction & 0x60000000) >> 29) | ((instruction & 0x01FFFFE0) >> 3);
+                       encodedAddend *= 4096; // internally addend is in bytes, so scale
+                       if ( encodedAddend != 0 ) {
+                               if ( prefixRelocAddend == 0 ) {
+                                       warning("adrp instruction at 0x%08X has embedded addend. ARM64_RELOC_ADDEND should be used instead", reloc->r_address());
+                                       target.addend = encodedAddend;
+                               }
+                               else {
+                                       throwf("adrp instruction at 0x%08X has embedded addend and ARM64_RELOC_ADDEND also used", reloc->r_address());
+                               }
+                       }
+                       parser.addFixups(src, ld::Fixup::kindStoreARM64Page21, target);
+                       break;
+               case ARM64_RELOC_PAGEOFF12:
+                       if ( reloc->r_pcrel() )
+                               throw "pcrel and ARM64_RELOC_PAGEOFF12 not supported";
+                       if ( ! reloc->r_extern() ) 
+                               throw "r_extern == 0 and ARM64_RELOC_PAGEOFF12 not supported";
+                       if ( reloc->r_length() != 2 ) 
+                               throw "length != 2 and ARM64_RELOC_PAGEOFF12 not supported";
+                       target.addend = prefixRelocAddend;
+                       instruction = contentValue;
+                       encodedAddend = ((instruction & 0x003FFC00) >> 10);
+            // internally addend is in bytes.  Some instructions have an implicit scale factor
+            if ( (instruction & 0x3B000000) == 0x39000000 ) {
+                switch ( instruction & 0xC0000000 ) {
+                    case 0x00000000:
+                        break;
+                    case 0x40000000:
+                        encodedAddend *= 2;
+                        break;
+                    case 0x80000000:
+                        encodedAddend *= 4;
+                        break;
+                    case 0xC0000000:
+                        encodedAddend *= 8;
+                        break;
+                               }
+            }
+                       if ( encodedAddend != 0 ) {
+                               if ( prefixRelocAddend == 0 ) {
+                                       warning("pageoff12 instruction at 0x%08X has embedded addend. ARM64_RELOC_ADDEND should be used instead", reloc->r_address());
+                                       target.addend = encodedAddend;
+                               }
+                               else {  
+                                       throwf("pageoff12 instruction at 0x%08X has embedded addend and ARM64_RELOC_ADDEND also used", reloc->r_address());
+                               }
+                       }
+                       parser.addFixups(src, ld::Fixup::kindStoreARM64PageOff12, target);
+                       break;
+               case ARM64_RELOC_GOT_LOAD_PAGE21:
+                       if ( ! reloc->r_pcrel() )
+                               throw "not pcrel and ARM64_RELOC_GOT_LOAD_PAGE21 not supported";
+                       if ( ! reloc->r_extern() ) 
+                               throw "r_extern == 0 and ARM64_RELOC_GOT_LOAD_PAGE21 not supported";
+                       if ( reloc->r_length() != 2 ) 
+                               throw "length != 2 and ARM64_RELOC_GOT_LOAD_PAGE21 not supported";
+                       if ( prefixRelocAddend != 0 )
+                               throw "ARM64_RELOC_ADDEND followed by ARM64_RELOC_GOT_LOAD_PAGE21 not supported";
+                       instruction = contentValue;
+                       target.addend = ((instruction & 0x60000000) >> 29) | ((instruction & 0x01FFFFE0) >> 3);
+            if ( target.addend != 0 )
+                throw "non-zero addend with ARM64_RELOC_GOT_LOAD_PAGE21 is not supported";
+                       parser.addFixups(src, ld::Fixup::kindStoreARM64GOTLoadPage21, target);
+                       break;
+               case ARM64_RELOC_GOT_LOAD_PAGEOFF12:
+                       if ( reloc->r_pcrel() )
+                               throw "pcrel and ARM64_RELOC_GOT_LOAD_PAGEOFF12 not supported";
+                       if ( ! reloc->r_extern() ) 
+                               throw "r_extern == 0 and ARM64_RELOC_GOT_LOAD_PAGEOFF12 not supported";
+                       if ( reloc->r_length() != 2 ) 
+                               throw "length != 2 and ARM64_RELOC_GOT_LOAD_PAGEOFF12 not supported";
+                       if ( prefixRelocAddend != 0 )
+                               throw "ARM64_RELOC_ADDEND followed by ARM64_RELOC_GOT_LOAD_PAGEOFF12 not supported";
+                       instruction = contentValue;
+                       target.addend = ((instruction & 0x003FFC00) >> 10);
+                       parser.addFixups(src, ld::Fixup::kindStoreARM64GOTLoadPageOff12, target);
+                       break;
+               case ARM64_RELOC_TLVP_LOAD_PAGE21:
+                       if ( ! reloc->r_pcrel() )
+                               throw "not pcrel and ARM64_RELOC_TLVP_LOAD_PAGE21 not supported";
+                       if ( ! reloc->r_extern() ) 
+                               throw "r_extern == 0 and ARM64_RELOC_TLVP_LOAD_PAGE21 not supported";
+                       if ( reloc->r_length() != 2 ) 
+                               throw "length != 2 and ARM64_RELOC_TLVP_LOAD_PAGE21 not supported";
+                       if ( prefixRelocAddend != 0 )
+                               throw "ARM64_RELOC_ADDEND followed by ARM64_RELOC_TLVP_LOAD_PAGE21 not supported";
+                       instruction = contentValue;
+                       target.addend = ((instruction & 0x60000000) >> 29) | ((instruction & 0x01FFFFE0) >> 3);
+            if ( target.addend != 0 )
+                throw "non-zero addend with ARM64_RELOC_GOT_LOAD_PAGE21 is not supported";
+                       parser.addFixups(src, ld::Fixup::kindStoreARM64TLVPLoadPage21, target);
+                       break;
+               case ARM64_RELOC_TLVP_LOAD_PAGEOFF12:
+                       if ( reloc->r_pcrel() )
+                               throw "pcrel and ARM64_RELOC_TLVP_LOAD_PAGEOFF12 not supported";
+                       if ( ! reloc->r_extern() ) 
+                               throw "r_extern == 0 and ARM64_RELOC_TLVP_LOAD_PAGEOFF12 not supported";
+                       if ( reloc->r_length() != 2 ) 
+                               throw "length != 2 and ARM64_RELOC_TLVP_LOAD_PAGEOFF12 not supported";
+                       if ( prefixRelocAddend != 0 )
+                               throw "ARM64_RELOC_ADDEND followed by ARM64_RELOC_TLVP_LOAD_PAGEOFF12 not supported";
+                       instruction = contentValue;
+                       target.addend = ((instruction & 0x003FFC00) >> 10);
+                       parser.addFixups(src, ld::Fixup::kindStoreARM64TLVPLoadPageOff12, target);
+                       break;
+               case ARM64_RELOC_SUBTRACTOR:
+                       if ( reloc->r_pcrel() )
+                               throw "ARM64_RELOC_SUBTRACTOR cannot be pc-relative";
+                       if ( reloc->r_length() < 2 )
+                               throw "ARM64_RELOC_SUBTRACTOR must have r_length of 2 or 3";
+                       if ( !reloc->r_extern() )
+                               throw "ARM64_RELOC_SUBTRACTOR must have r_extern=1";
+                       if ( nextReloc->r_type() != ARM64_RELOC_UNSIGNED )
+                               throw "ARM64_RELOC_SUBTRACTOR must be followed by ARM64_RELOC_UNSIGNED";
+                       if ( prefixRelocAddend != 0 )
+                               throw "ARM64_RELOC_ADDEND followed by ARM64_RELOC_SUBTRACTOR not supported";
+                       result = true;
+                       if ( nextReloc->r_pcrel() )
+                               throw "ARM64_RELOC_UNSIGNED following a ARM64_RELOC_SUBTRACTOR cannot be pc-relative";
+                       if ( nextReloc->r_length() != reloc->r_length() )
+                               throw "ARM64_RELOC_UNSIGNED following a ARM64_RELOC_SUBTRACTOR must have same r_length";
+                       if ( nextReloc->r_extern() ) {
+                               const macho_nlist<P>& sym = parser.symbolFromIndex(nextReloc->r_symbolnum());
+                               // use direct reference for local symbols
+                               if ( ((sym.n_type() & N_TYPE) == N_SECT) && (((sym.n_type() & N_EXT) == 0) || (parser.nameFromSymbol(sym)[0] == 'L')) ) {
+                                       parser.findTargetFromAddressAndSectionNum(sym.n_value(), sym.n_sect(), toTarget);
+                                       toTarget.addend = contentValue;
+                                       useDirectBinding = true;
+                               }
+                               else {
+                                       toTarget.name = parser.nameFromSymbol(sym);
+                                       toTarget.weakImport = parser.weakImportFromSymbol(sym);
+                                       toTarget.addend = contentValue;
+                                       useDirectBinding = false;
+                               }
+                       }
+                       else {
+                               parser.findTargetFromAddressAndSectionNum(contentValue, nextReloc->r_symbolnum(), toTarget);
+                               useDirectBinding = (toTarget.atom->scope() == ld::Atom::scopeTranslationUnit);
+                       }
+                       if ( useDirectBinding )
+                               parser.addFixup(src, ld::Fixup::k1of4, ld::Fixup::kindSetTargetAddress, toTarget.atom);
+                       else
+                               parser.addFixup(src, ld::Fixup::k1of4, ld::Fixup::kindSetTargetAddress, toTarget.weakImport, toTarget.name);
+                       parser.addFixup(src, ld::Fixup::k2of4, ld::Fixup::kindAddAddend, toTarget.addend);
+                       if ( target.atom == NULL )
+                               parser.addFixup(src, ld::Fixup::k3of4, ld::Fixup::kindSubtractTargetAddress, false, target.name);
+                       else
+                               parser.addFixup(src, ld::Fixup::k3of4, ld::Fixup::kindSubtractTargetAddress, target.atom);
+                       if ( reloc->r_length() == 2 )
+                               parser.addFixup(src, ld::Fixup::k4of4, ld::Fixup::kindStoreLittleEndian32);
+                       else
+                               parser.addFixup(src, ld::Fixup::k4of4, ld::Fixup::kindStoreLittleEndian64);
+                       break;
+        case ARM64_RELOC_POINTER_TO_GOT:
+                       if ( ! reloc->r_extern() ) 
+                               throw "r_extern == 0 and ARM64_RELOC_POINTER_TO_GOT not supported";
+                       if ( prefixRelocAddend != 0 )
+                               throw "ARM64_RELOC_ADDEND followed by ARM64_RELOC_POINTER_TO_GOT not supported";
+                       if ( reloc->r_pcrel() ) {
+                if ( reloc->r_length() != 2 ) 
+                    throw "r_length != 2 and r_extern = 1 and ARM64_RELOC_POINTER_TO_GOT not supported";
+                parser.addFixups(src, ld::Fixup::kindStoreARM64PCRelToGOT, target);
+            }
+            else {
+                if ( reloc->r_length() != 3 ) 
+                    throw "r_length != 3 and r_extern = 0 and ARM64_RELOC_POINTER_TO_GOT not supported";
+                parser.addFixups(src, ld::Fixup::kindStoreARM64PointerToGOT, target);
+            }
+            break;
+               default:
+                       throwf("unknown relocation type %d", reloc->r_type());
+       }
+       return result;
+}
+#endif
 
 template <typename A>
 bool ObjC1ClassSection<A>::addRelocFixup(class Parser<A>& parser, const macho_relocation_info<P>* reloc)
@@ -6146,6 +6891,72 @@ bool Objc1ClassReferences<x86>::addRelocFixup(class Parser<x86>& parser, const m
        return PointerToCStringSection<x86>::addRelocFixup(parser, reloc);
 }
 
+#if SUPPORT_ARCH_arm64
+template <>
+void Section<arm64>::addLOH(class Parser<arm64>& parser, int kind, int count, const uint64_t addrs[]) {
+       switch (kind) {
+               case LOH_ARM64_ADRP_ADRP:
+               case LOH_ARM64_ADRP_LDR:
+               case LOH_ARM64_ADRP_ADD:
+               case LOH_ARM64_ADRP_LDR_GOT:
+                       if ( count != 2 )
+                               warning("arm64 Linker Optimiztion Hint %d has wrong number of arguments", kind);
+                       break;
+               case LOH_ARM64_ADRP_ADD_LDR:
+               case LOH_ARM64_ADRP_LDR_GOT_LDR:
+               case LOH_ARM64_ADRP_ADD_STR:
+               case LOH_ARM64_ADRP_LDR_GOT_STR:
+                       if ( count != 3 )
+                               warning("arm64 Linker Optimiztion Hint %d has wrong number of arguments", kind);
+       }
+       
+       // pick lowest address in tuple for use as offsetInAtom
+       uint64_t lowestAddress = addrs[0];
+       for(int i=1; i < count; ++i) {
+               if ( addrs[i] < lowestAddress )
+                       lowestAddress = addrs[i];
+       }
+       // verify all other address are in same atom
+       Atom<arm64>* inAtom = parser.findAtomByAddress(lowestAddress);
+       const uint64_t atomStartAddr = inAtom->objectAddress();
+       const uint64_t atomEndAddr = atomStartAddr + inAtom->size();
+       for(int i=0; i < count; ++i) {
+               if ( (addrs[i] < atomStartAddr) || (addrs[i] >= atomEndAddr) ) {
+                       warning("arm64 Linker Optimiztion Hint addresses are not in same atom: 0x%08llX and 0x%08llX",
+                               lowestAddress, addrs[i]);
+                       return; // skip this LOH
+               }
+               if ( (addrs[i] & 0x3) != 0 ) {
+                       warning("arm64 Linker Optimiztion Hint address is not 4-byte aligned: 0x%08llX", addrs[i]);
+                       return; // skip this LOH
+               }
+               if ( (addrs[i] - lowestAddress) > 0xFFFF ) {
+                       if ( parser.verboseOptimizationHints() ) {
+                               warning("arm64 Linker Optimiztion Hint addresses are too far apart: 0x%08llX and 0x%08llX",
+                                       lowestAddress, addrs[i]);
+                       }
+                       return; // skip this LOH
+               }
+       }
+       
+       // encoded kind, count, and address deltas in 64-bit addend 
+       ld::Fixup::LOH_arm64 extra;
+       extra.addend = 0;
+       extra.info.kind = kind;
+       extra.info.count = count-1;
+       extra.info.delta1 = (addrs[0] - lowestAddress) >> 2;
+       extra.info.delta2 = (count > 1) ? ((addrs[1] - lowestAddress) >> 2) : 0;
+       extra.info.delta3 = (count > 2) ? ((addrs[2] - lowestAddress) >> 2) : 0;
+       extra.info.delta4 = (count > 3) ? ((addrs[3] - lowestAddress) >> 2) : 0;
+       typename Parser<arm64>::SourceLocation src(inAtom, lowestAddress- inAtom->objectAddress());
+       parser.addFixup(src, ld::Fixup::k1of1, ld::Fixup::kindLinkerOptimizationHint, extra.addend);
+}
+#endif
+
+template <typename A>
+void Section<A>::addLOH(class Parser<A>& parser, int kind, int count, const uint64_t addrs[]) {
+
+}
 
 template <typename A>
 void Section<A>::makeFixups(class Parser<A>& parser, const struct Parser<A>::CFI_CU_InfoArrays&)
@@ -6261,6 +7072,42 @@ void Section<A>::makeFixups(class Parser<A>& parser, const struct Parser<A>::CFI
                }
        }
        
+       // <rdar://problem/11945700> convert linker optimization hints into internal format
+       if ( this->type() == ld::Section::typeCode && parser.hasOptimizationHints() ) {
+               const pint_t startAddr = this->_machOSection->addr();
+               const pint_t endAddr = startAddr + this->_machOSection->size();
+               for (const uint8_t* p = parser.optimizationHintsStart(); p < parser.optimizationHintsEnd(); ) {
+                       uint64_t addrs[4];
+                       int32_t kind = read_uleb128(&p, parser.optimizationHintsEnd());
+                       if ( kind == 0 ) // padding at end of loh buffer
+                               break;
+                       if ( kind == -1 ) {
+                               warning("malformed uleb128 kind in LC_LINKER_OPTIMIZATION_HINTS");
+                               break;
+                       }
+                       int32_t count = read_uleb128(&p, parser.optimizationHintsEnd());
+                       if ( count == -1 ) {
+                               warning("malformed uleb128 count in LC_LINKER_OPTIMIZATION_HINTS");
+                               break;
+                       }
+                       if ( count > 3 ) {
+                               warning("address count > 3 in LC_LINKER_OPTIMIZATION_HINTS");
+                               break;
+                       }
+                       for (int32_t i=0; i < count; ++i) {
+                               addrs[i] = read_uleb128(&p, parser.optimizationHintsEnd());
+                       }
+                       if ( (startAddr <= addrs[0]) && (addrs[0] < endAddr) ) {
+                               this->addLOH(parser, kind, count, addrs);
+                               //fprintf(stderr, "kind=%d", kind);
+                               //for (int32_t i=0; i < count; ++i) {
+                               //      fprintf(stderr, ", addr=0x%08llX", addrs[i]);
+                               //}
+                               //fprintf(stderr, "\n");
+                       }
+               }
+       }
+       
        
        // add follow-on fixups for aliases
        if ( _hasAliases ) {
@@ -6302,6 +7149,12 @@ ld::relocatable::File* parse(const uint8_t* fileContent, uint64_t fileLength,
                        if ( mach_o::relocatable::Parser<arm>::validFile(fileContent, opts.objSubtypeMustMatch, opts.subType) )
                                return mach_o::relocatable::Parser<arm>::parse(fileContent, fileLength, path, modTime, ordinal, opts);
                        break;
+#endif
+#if SUPPORT_ARCH_arm64
+               case CPU_TYPE_ARM64:
+                       if ( mach_o::relocatable::Parser<arm64>::validFile(fileContent, opts.objSubtypeMustMatch, opts.subType) )
+                               return mach_o::relocatable::Parser<arm64>::parse(fileContent, fileLength, path, modTime, ordinal, opts);
+                       break;
 #endif
        }
        return NULL;
@@ -6319,6 +7172,8 @@ bool isObjectFile(const uint8_t* fileContent, uint64_t fileLength, const ParserO
                        return ( mach_o::relocatable::Parser<x86>::validFile(fileContent) );
                case CPU_TYPE_ARM:
                        return ( mach_o::relocatable::Parser<arm>::validFile(fileContent, opts.objSubtypeMustMatch, opts.subType) );
+               case CPU_TYPE_ARM64:
+                       return ( mach_o::relocatable::Parser<arm64>::validFile(fileContent, opts.objSubtypeMustMatch, opts.subType) );
        }
        return false;
 }
@@ -6330,7 +7185,8 @@ bool isObjectFile(const uint8_t* fileContent, cpu_type_t* result, cpu_subtype_t*
 {
        if ( mach_o::relocatable::Parser<x86_64>::validFile(fileContent) ) {
                *result = CPU_TYPE_X86_64;
-               *subResult = CPU_SUBTYPE_X86_64_ALL;
+               const macho_header<Pointer64<LittleEndian> >* header = (const macho_header<Pointer64<LittleEndian> >*)fileContent;
+               *subResult = header->cpusubtype();
                return true;
        }
        if ( mach_o::relocatable::Parser<x86>::validFile(fileContent) ) {
@@ -6344,6 +7200,11 @@ bool isObjectFile(const uint8_t* fileContent, cpu_type_t* result, cpu_subtype_t*
                *subResult = header->cpusubtype();
                return true;
        }
+       if ( mach_o::relocatable::Parser<arm64>::validFile(fileContent, false, 0) ) {
+               *result = CPU_TYPE_ARM64;
+               *subResult = CPU_SUBTYPE_ARM64_ALL;
+               return true;
+       }
        return false;
 }                                      
 
@@ -6378,6 +7239,11 @@ bool hasObjC2Categories(const uint8_t* fileContent)
        else if ( mach_o::relocatable::Parser<x86>::validFile(fileContent, false, 0) ) {
                return mach_o::relocatable::Parser<x86>::hasObjC2Categories(fileContent);
        }
+#if SUPPORT_ARCH_arm64
+    else if ( mach_o::relocatable::Parser<arm64>::validFile(fileContent, false, 0) ) {
+        return mach_o::relocatable::Parser<arm64>::hasObjC2Categories(fileContent);
+    }
+#endif
        return false;
 }