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dyld3/shared-cache/CacheBuilder.cpp dyld-851.27 dyld-519.2.2
--- dyld/dyld-851.27/dyld3/shared-cache/CacheBuilder.cpp
+++ dyld/dyld-519.2.2/dyld3/shared-cache/CacheBuilder.cpp
@@ -22,24 +22,90 @@
  * @APPLE_LICENSE_HEADER_END@
  */
 
+
+#include <unistd.h>
+#include <dirent.h>
+#include <sys/errno.h>
+#include <sys/fcntl.h>
+#include <sys/param.h>
+#include <mach/mach.h>
+#include <mach/mach_time.h>
+#include <mach-o/loader.h>
+#include <mach-o/fat.h>
+#include <mach/shared_region.h>
 #include <assert.h>
-
-#include "MachOFileAbstraction.hpp"
+#include <CommonCrypto/CommonHMAC.h>
+#include <CommonCrypto/CommonDigest.h>
+#include <CommonCrypto/CommonDigestSPI.h>
+#include <pthread/pthread.h>
+
+#include <string>
+#include <vector>
+#include <unordered_map>
+#include <unordered_set>
+
+#include "MachOParser.h"
+#include "CodeSigningTypes.h"
 #include "DyldSharedCache.h"
 #include "CacheBuilder.h"
+#include "FileAbstraction.hpp"
+#include "LaunchCacheWriter.h"
+#include "Trie.hpp"
 #include "Diagnostics.h"
-#include "IMPCaches.hpp"
-
-CacheBuilder::CacheBuilder(const DyldSharedCache::CreateOptions& options, const dyld3::closure::FileSystem& fileSystem)
+#include "ImageProxy.h"
+
+#if __has_include("dyld_cache_config.h")
+    #include "dyld_cache_config.h"
+#else
+    #define ARM_SHARED_REGION_START    0x1A000000ULL
+    #define ARM_SHARED_REGION_SIZE     0x26000000ULL
+    #define ARM64_SHARED_REGION_START 0x180000000ULL
+    #define ARM64_SHARED_REGION_SIZE   0x40000000ULL
+#endif
+
+const CacheBuilder::ArchLayout CacheBuilder::_s_archLayout[] = {
+    { 0x7FFF20000000ULL,         0xEFE00000ULL,             0x40000000, 0xFFFF000000000000, "x86_64",  0,          0,          0,          12, true,  true  },
+    { 0x7FFF20000000ULL,         0xEFE00000ULL,             0x40000000, 0xFFFF000000000000, "x86_64h", 0,          0,          0,          12, true,  true  },
+    { SHARED_REGION_BASE_I386,   SHARED_REGION_SIZE_I386,   0x00200000,                0x0, "i386",    0,          0,          0,          12, false, false },
+    { ARM64_SHARED_REGION_START, ARM64_SHARED_REGION_SIZE,  0x02000000, 0x00FFFF0000000000, "arm64",   0x0000C000, 0x00100000, 0x07F00000, 14, false, true  },
+    { ARM64_SHARED_REGION_START, ARM64_SHARED_REGION_SIZE,  0x02000000, 0x00FFFF0000000000, "arm64e",  0x0000C000, 0x00100000, 0x07F00000, 14, false, true  },
+    { ARM_SHARED_REGION_START,   ARM_SHARED_REGION_SIZE,    0x02000000,         0xE0000000, "armv7s",  0,          0,          0,          14, false, false },
+    { ARM_SHARED_REGION_START,   ARM_SHARED_REGION_SIZE,    0x00400000,         0xE0000000, "armv7k",  0,          0,          0,          14, false, false },
+    { 0x40000000,                0x40000000,                0x02000000,                0x0, "sim-x86", 0,          0,          0,          14, false, false }
+};
+
+
+// These are dylibs that may be interposed, so stubs calling into them should never be bypassed
+const char* const CacheBuilder::_s_neverStubEliminate[] = {
+    "/usr/lib/system/libdispatch.dylib",
+    nullptr
+};
+
+
+CacheBuilder::CacheBuilder(const DyldSharedCache::CreateOptions& options)
     : _options(options)
-    , _fileSystem(fileSystem)
-    , _fullAllocatedBuffer(0)
+    , _buffer(nullptr)
     , _diagnostics(options.loggingPrefix, options.verbose)
+    , _archLayout(nullptr)
+    , _aliasCount(0)
+    , _slideInfoFileOffset(0)
+    , _slideInfoBufferSizeAllocated(0)
     , _allocatedBufferSize(0)
-{
-}
-
-CacheBuilder::~CacheBuilder() {
+    , _currentFileSize(0)
+    , _vmSize(0)
+    , _branchPoolsLinkEditStartAddr(0)
+{
+
+    std::string targetArch = options.archName;
+    if ( options.forSimulator && (options.archName == "i386") )
+        targetArch = "sim-x86";
+
+    for (const ArchLayout& layout : _s_archLayout) {
+        if ( layout.archName == targetArch ) {
+            _archLayout = &layout;
+            break;
+        }
+    }
 }
 
 
@@ -48,767 +114,1671 @@
     return _diagnostics.errorMessage();
 }
 
-void CacheBuilder::copyRawSegments()
+const std::set<std::string> CacheBuilder::warnings()
+{
+    return _diagnostics.warnings();
+}
+
+void CacheBuilder::deleteBuffer()
+{
+    vm_deallocate(mach_task_self(), (vm_address_t)_buffer, _allocatedBufferSize);
+    _buffer = nullptr;
+    _allocatedBufferSize = 0;
+}
+
+std::vector<DyldSharedCache::MappedMachO>
+CacheBuilder::makeSortedDylibs(const std::vector<DyldSharedCache::MappedMachO>& dylibs, const std::unordered_map<std::string, unsigned> sortOrder)
+{
+    std::vector<DyldSharedCache::MappedMachO> sortedDylibs = dylibs;
+
+    std::sort(sortedDylibs.begin(), sortedDylibs.end(), [&](const DyldSharedCache::MappedMachO& a, const DyldSharedCache::MappedMachO& b) {
+        const auto& orderA = sortOrder.find(a.runtimePath);
+        const auto& orderB = sortOrder.find(b.runtimePath);
+        bool foundA = (orderA != sortOrder.end());
+        bool foundB = (orderB != sortOrder.end());
+
+        // Order all __DATA_DIRTY segments specified in the order file first, in
+        // the order specified in the file, followed by any other __DATA_DIRTY
+        // segments in lexicographic order.
+        if ( foundA && foundB )
+            return orderA->second < orderB->second;
+        else if ( foundA )
+            return true;
+        else if ( foundB )
+             return false;
+        else
+             return a.runtimePath < b.runtimePath;
+    });
+
+    return sortedDylibs;
+}
+
+
+inline uint32_t absolutetime_to_milliseconds(uint64_t abstime)
+{
+    return (uint32_t)(abstime/1000/1000);
+}
+
+struct DylibAndSize
+{
+    const char*     installName;
+    uint64_t        size;
+};
+
+bool CacheBuilder::cacheOverflow(const dyld_cache_mapping_info regions[3])
+{
+    if ( _archLayout->sharedRegionsAreDiscontiguous ) {
+        // for macOS x86_64 cache, need to check each region for overflow
+        return ( (regions[0].size > 0x60000000) || (regions[1].size > 0x40000000) || (regions[2].size > 0x3FE00000) );
+    }
+    else {
+        return (_vmSize > _archLayout->sharedMemorySize);
+    }
+}
+
+bool CacheBuilder::build(const std::vector<DyldSharedCache::MappedMachO>& dylibs,
+                         const std::vector<DyldSharedCache::MappedMachO>& otherOsDylibsInput,
+                         const std::vector<DyldSharedCache::MappedMachO>& osExecutables)
+{
+    // <rdar://problem/21317611> error out instead of crash if cache has no dylibs
+    // FIXME: plist should specify required vs optional dylibs
+    if ( dylibs.size() < 30 ) {
+        _diagnostics.error("missing required minimum set of dylibs");
+        return false;
+    }
+    uint64_t t1 = mach_absolute_time();
+
+
+    // make copy of dylib list and sort
+    std::vector<DyldSharedCache::MappedMachO> sortedDylibs = makeSortedDylibs(dylibs, _options.dylibOrdering);
+    std::vector<DyldSharedCache::MappedMachO> otherOsDylibs = otherOsDylibsInput;
+
+    // assign addresses for each segment of each dylib in new cache
+    dyld_cache_mapping_info regions[3];
+    SegmentMapping segmentMapping = assignSegmentAddresses(sortedDylibs, regions);
+    if ( cacheOverflow(regions) ) {
+        if ( !_options.evictLeafDylibsOnOverflow ) {
+            _diagnostics.error("cache overflow: %lluMB (max %lluMB)", _vmSize / 1024 / 1024, (_archLayout->sharedMemorySize) / 1024 / 1024);
+            return false;
+        }
+        // find all leaf (not referenced by anything else in cache) dylibs
+
+        // build count of how many references there are to each dylib
+        __block std::map<std::string, unsigned int> referenceCount;
+        for (const DyldSharedCache::MappedMachO& dylib : sortedDylibs) {
+            dyld3::MachOParser parser(dylib.mh);
+            parser.forEachDependentDylib(^(const char* loadPath, bool isWeak, bool isReExport, bool isUpward, uint32_t compatVersion, uint32_t curVersion, bool &stop) {
+                referenceCount[loadPath] += 1;
+            });
+        }
+
+        // find all dylibs not referenced
+        std::vector<DylibAndSize> unreferencedDylibs;
+        for (const DyldSharedCache::MappedMachO& dylib : sortedDylibs) {
+            dyld3::MachOParser parser(dylib.mh);
+            const char* installName = parser.installName();
+            if ( referenceCount.count(installName) == 0 ) {
+                // conservative: sum up all segments except LINKEDIT
+                __block uint64_t segsSize = 0;
+                parser.forEachSegment(^(const char* segName, uint32_t fileOffset, uint32_t fileSize, uint64_t vmAddr, uint64_t vmSize, uint8_t protections, bool &stop) {
+                    if ( strcmp(segName, "__LINKEDIT") != 0 )
+                        segsSize += vmSize;
+                });
+                unreferencedDylibs.push_back({installName, segsSize});
+            }
+        }
+        // sort leaf dylibs by size
+        std::sort(unreferencedDylibs.begin(), unreferencedDylibs.end(), [&](const DylibAndSize& a, const DylibAndSize& b) {
+            return ( a.size > b.size );
+        });
+
+        // build set of dylibs that if removed will allow cache to build
+        uint64_t reductionTarget = _vmSize - _archLayout->sharedMemorySize;
+        std::set<std::string> toRemove;
+        for (DylibAndSize& dylib : unreferencedDylibs) {
+            if ( _options.verbose )
+                _diagnostics.warning("to prevent cache overflow, not caching %s", dylib.installName);
+            toRemove.insert(dylib.installName);
+            if ( dylib.size > reductionTarget )
+                break;
+            reductionTarget -= dylib.size;
+        }
+        // transfer overflow dylibs from cached vector to other vector
+        for (const std::string& installName : toRemove) {
+            for (std::vector<DyldSharedCache::MappedMachO>::iterator it=sortedDylibs.begin(); it != sortedDylibs.end(); ++it) {
+                dyld3::MachOParser parser(it->mh);
+                if ( installName == parser.installName() ) {
+                    otherOsDylibs.push_back(*it);
+                    sortedDylibs.erase(it);
+                    break;
+                }
+            }
+        }
+        // re-layout cache
+        segmentMapping = assignSegmentAddresses(sortedDylibs, regions);
+        if ( cacheOverflow(regions) ) {
+            _diagnostics.error("cache overflow, tried evicting %ld leaf daylibs, but still too big: %lluMB (max %lluMB)",
+                               toRemove.size(), _vmSize / 1024 / 1024, (_archLayout->sharedMemorySize) / 1024 / 1024);
+            return false;
+        }
+    }
+
+    // allocate buffer for new cache
+    _allocatedBufferSize = std::max(_currentFileSize, (uint64_t)0x100000)*1.1; // add 10% to allocation to support large closures
+    if ( vm_allocate(mach_task_self(), (vm_address_t*)&_buffer, _allocatedBufferSize, VM_FLAGS_ANYWHERE) != 0 ) {
+        _diagnostics.error("could not allocate buffer");
+        return false;
+    }
+    _currentFileSize = _allocatedBufferSize;
+
+    // write unoptimized cache
+    writeCacheHeader(regions, sortedDylibs, segmentMapping);
+    copyRawSegments(sortedDylibs, segmentMapping);
+    adjustAllImagesForNewSegmentLocations(sortedDylibs, segmentMapping);
+    if ( _diagnostics.hasError() )
+        return false;
+
+    bindAllImagesInCacheFile(regions);
+    if ( _diagnostics.hasError() )
+        return false;
+
+    // optimize ObjC
+    if ( _options.optimizeObjC )
+        optimizeObjC(_buffer, _archLayout->is64, _options.optimizeStubs, _pointersForASLR, _diagnostics);
+    if ( _diagnostics.hasError() )
+        return false;
+
+    // optimize away stubs
+    std::vector<uint64_t> branchPoolOffsets;
+    uint64_t cacheStartAddress = _archLayout->sharedMemoryStart;
+    if ( _options.optimizeStubs ) {
+        std::vector<uint64_t> branchPoolStartAddrs;
+        const uint64_t* p = (uint64_t*)((uint8_t*)_buffer + _buffer->header.branchPoolsOffset);
+        for (int i=0; i < _buffer->header.branchPoolsCount; ++i) {
+            uint64_t poolAddr = p[i];
+            branchPoolStartAddrs.push_back(poolAddr);
+            branchPoolOffsets.push_back(poolAddr - cacheStartAddress);
+        }
+        bypassStubs(_buffer, branchPoolStartAddrs, _s_neverStubEliminate, _diagnostics);
+    }
+    uint64_t t2 = mach_absolute_time();
+
+    // FIPS seal corecrypto, This must be done after stub elimination (so that
+    // __TEXT,__text is not changed after sealing), but before LINKEDIT
+    // optimization  (so that we still have access to local symbols)
+    fipsSign();
+
+    // merge and compact LINKEDIT segments
+    dyld_cache_local_symbols_info* localsInfo = nullptr;
+    if ( dylibs.size() == 0 )
+        _currentFileSize = 0x1000;
+    else
+        _currentFileSize = optimizeLinkedit(_buffer, _archLayout->is64, _options.excludeLocalSymbols, _options.optimizeStubs, branchPoolOffsets, _diagnostics, &localsInfo);
+
+    uint64_t t3 = mach_absolute_time();
+
+    // add ImageGroup for all dylibs in cache
+    __block std::vector<DyldSharedCache::MappedMachO> cachedDylibs;
+    std::unordered_map<std::string, const DyldSharedCache::MappedMachO*> mapIntoSortedDylibs;
+    for (const DyldSharedCache::MappedMachO& entry : sortedDylibs) {
+        mapIntoSortedDylibs[entry.runtimePath] = &entry;
+    }
+    _buffer->forEachImage(^(const mach_header* mh, const char* installName) {
+        auto pos = mapIntoSortedDylibs.find(installName);
+        if ( pos != mapIntoSortedDylibs.end() ) {
+            DyldSharedCache::MappedMachO newEntry = *(pos->second);
+            newEntry.mh = mh;
+            cachedDylibs.push_back(newEntry);
+        }
+        else {
+            bool found = false;
+            for (const std::string& prefix :  _options.pathPrefixes) {
+                std::string fullPath = prefix + installName;
+                char resolvedPath[PATH_MAX];
+                if ( realpath(fullPath.c_str(), resolvedPath) != nullptr ) {
+                    std::string resolvedUnPrefixed = &resolvedPath[prefix.size()];
+                    pos = mapIntoSortedDylibs.find(resolvedUnPrefixed);
+                    if ( pos != mapIntoSortedDylibs.end() ) {
+                        DyldSharedCache::MappedMachO newEntry = *(pos->second);
+                        newEntry.mh = mh;
+                        cachedDylibs.push_back(newEntry);
+                        found = true;
+                   }
+                }
+            }
+            if ( !found )
+                fprintf(stderr, "missing mapping for %s\n", installName);
+        }
+    });
+    dyld3::DyldCacheParser dyldCacheParser(_buffer, true);
+    dyld3::ImageProxyGroup* dylibGroup = dyld3::ImageProxyGroup::makeDyldCacheDylibsGroup(_diagnostics, dyldCacheParser, cachedDylibs,
+                                                                                          _options.pathPrefixes, _patchTable,
+                                                                                          _options.optimizeStubs, !_options.dylibsRemovedDuringMastering);
+    if ( _diagnostics.hasError() )
+        return false;
+    addCachedDylibsImageGroup(dylibGroup);
+    if ( _diagnostics.hasError() )
+        return false;
+
+    uint64_t t4 = mach_absolute_time();
+
+    // add ImageGroup for other OS dylibs and bundles
+    dyld3::ImageProxyGroup* otherGroup = dyld3::ImageProxyGroup::makeOtherOsGroup(_diagnostics, dyldCacheParser, dylibGroup, otherOsDylibs,
+                                                                                  _options.inodesAreSameAsRuntime, _options.pathPrefixes);
+    if ( _diagnostics.hasError() )
+        return false;
+    addCachedOtherDylibsImageGroup(otherGroup);
+    if ( _diagnostics.hasError() )
+        return false;
+
+    uint64_t t5 = mach_absolute_time();
+
+    // compute and add launch closures
+    std::map<std::string, const dyld3::launch_cache::binary_format::Closure*> closures;
+    for (const DyldSharedCache::MappedMachO& mainProg : osExecutables) {
+        Diagnostics clsDiag;
+        const dyld3::launch_cache::binary_format::Closure* cls = dyld3::ImageProxyGroup::makeClosure(clsDiag, dyldCacheParser, dylibGroup, otherGroup, mainProg,
+                                                                                                     _options.inodesAreSameAsRuntime, _options.pathPrefixes);
+        if ( clsDiag.hasError() ) {
+            // if closure cannot be built, silently skip it, unless in verbose mode
+            if ( _options.verbose ) {
+                _diagnostics.warning("building closure for '%s': %s", mainProg.runtimePath.c_str(), clsDiag.errorMessage().c_str());
+                for (const std::string& warn : clsDiag.warnings() )
+                    _diagnostics.warning("%s", warn.c_str());
+            }
+        }
+        else {
+            closures[mainProg.runtimePath] = cls;
+       }
+    }
+    addClosures(closures);
+    if ( _diagnostics.hasError() )
+        return false;
+
+    uint64_t t6 = mach_absolute_time();
+
+    // fill in slide info at start of region[2]
+    // do this last because it modifies pointers in DATA segments
+    if ( _options.cacheSupportsASLR ) {
+        if ( _archLayout->is64 )
+            writeSlideInfoV2<Pointer64<LittleEndian>>();
+        else
+            writeSlideInfoV2<Pointer32<LittleEndian>>();
+    }
+
+    uint64_t t7 = mach_absolute_time();
+
+    // update last region size
+    dyld_cache_mapping_info* mappings = (dyld_cache_mapping_info*)((char*)_buffer + _buffer->header.mappingOffset);
+    _currentFileSize = align(_currentFileSize, _archLayout->sharedRegionAlignP2);
+    mappings[2].size = _currentFileSize - mappings[2].fileOffset;
+
+    // record cache bounds
+    _buffer->header.sharedRegionStart = _archLayout->sharedMemoryStart;
+    _buffer->header.sharedRegionSize  = _archLayout->sharedMemorySize;
+    if ( _archLayout->sharedRegionsAreDiscontiguous ) {
+        // special case x86_64 which has three non-contiguous chunks each in their own 1GB regions
+        uint64_t maxSlide0 = 0x60000000 - mappings[0].size; // TEXT region has 1.5GB region
+        uint64_t maxSlide1 = 0x40000000 - mappings[1].size;
+        uint64_t maxSlide2 = 0x3FE00000 - mappings[2].size;
+        _buffer->header.maxSlide = std::min(std::min(maxSlide0, maxSlide1), maxSlide2);
+    }
+    else {
+        _buffer->header.maxSlide = (_archLayout->sharedMemoryStart + _archLayout->sharedMemorySize) - (mappings[2].address + mappings[2].size);
+    }
+
+    // append "unmapped" local symbols region
+    if ( _options.excludeLocalSymbols ) {
+        size_t localsInfoSize = align(localsInfo->stringsOffset + localsInfo->stringsSize, _archLayout->sharedRegionAlignP2);
+        if ( _currentFileSize + localsInfoSize > _allocatedBufferSize ) {
+            _diagnostics.warning("local symbols omitted because cache buffer overflow");
+        }
+        else {
+            memcpy((char*)_buffer+_currentFileSize, localsInfo, localsInfoSize);
+            _buffer->header.localSymbolsOffset = _currentFileSize;
+            _buffer->header.localSymbolsSize   = localsInfoSize;
+            _currentFileSize += localsInfoSize;
+        }
+        free((void*)localsInfo);
+    }
+
+    recomputeCacheUUID();
+
+    // Calculate the VMSize of the resulting cache
+    __block uint64_t endAddr = 0;
+    _buffer->forEachRegion(^(const void* content, uint64_t vmAddr, uint64_t size, uint32_t permissions) {
+        if (vmAddr+size > endAddr)
+            endAddr = vmAddr+size;
+    });
+    _vmSize = endAddr - cacheStartAddress;
+
+    // last sanity check on size
+    if ( _vmSize > _archLayout->sharedMemorySize ) {
+        _diagnostics.error("cache overflow after optimizations.  %lluMB (max %lluMB)", _vmSize / 1024 / 1024, (_archLayout->sharedMemorySize) / 1024 / 1024);
+        return true;
+    }
+
+    // codesignature is part of file, but is not mapped
+    codeSign();
+    if ( _diagnostics.hasError() )
+        return false;
+
+    uint64_t t8 = mach_absolute_time();
+
+    if ( _options.verbose ) {
+        fprintf(stderr, "time to copy and bind cached dylibs: %ums\n", absolutetime_to_milliseconds(t2-t1));
+        fprintf(stderr, "time to optimize LINKEDITs: %ums\n", absolutetime_to_milliseconds(t3-t2));
+        fprintf(stderr, "time to build ImageGroup of %lu cached dylibs: %ums\n", sortedDylibs.size(), absolutetime_to_milliseconds(t4-t3));
+        fprintf(stderr, "time to build ImageGroup of %lu other dylibs: %ums\n", otherOsDylibs.size(), absolutetime_to_milliseconds(t5-t4));
+        fprintf(stderr, "time to build %lu closures: %ums\n", osExecutables.size(), absolutetime_to_milliseconds(t6-t5));
+        fprintf(stderr, "time to compute slide info: %ums\n", absolutetime_to_milliseconds(t7-t6));
+        fprintf(stderr, "time to compute UUID and codesign cache file: %ums\n", absolutetime_to_milliseconds(t8-t7));
+    }
+
+    // trim over allocated buffer
+    if ( _allocatedBufferSize > _currentFileSize ) {
+        uint8_t* startOfUnused  = (uint8_t*)_buffer+_currentFileSize;
+        size_t unusedLen = _allocatedBufferSize-_currentFileSize;
+        vm_deallocate(mach_task_self(), (vm_address_t)startOfUnused, unusedLen);
+        _allocatedBufferSize = _currentFileSize;
+    }
+
+    return false;
+}
+
+
+void CacheBuilder::writeCacheHeader(const dyld_cache_mapping_info regions[3], const std::vector<DyldSharedCache::MappedMachO>& dylibs, const SegmentMapping& segmentMappings)
+{
+    // "dyld_v1" + spaces + archName(), with enough spaces to pad to 15 bytes
+    std::string magic = "dyld_v1";
+    magic.append(15 - magic.length() - _options.archName.length(), ' ');
+    magic.append(_options.archName);
+    assert(magic.length() == 15);
+
+    // fill in header
+    memcpy(_buffer->header.magic, magic.c_str(), 16);
+    _buffer->header.mappingOffset      = sizeof(dyld_cache_header);
+    _buffer->header.mappingCount       = 3;
+    _buffer->header.imagesOffset       = (uint32_t)(_buffer->header.mappingOffset + 3*sizeof(dyld_cache_mapping_info) + sizeof(uint64_t)*_branchPoolStarts.size());
+    _buffer->header.imagesCount        = (uint32_t)dylibs.size() + _aliasCount;
+    _buffer->header.dyldBaseAddress    = 0;
+    _buffer->header.codeSignatureOffset= 0;
+    _buffer->header.codeSignatureSize  = 0;
+    _buffer->header.slideInfoOffset    = _slideInfoFileOffset;
+    _buffer->header.slideInfoSize      = _slideInfoBufferSizeAllocated;
+    _buffer->header.localSymbolsOffset = 0;
+    _buffer->header.localSymbolsSize   = 0;
+    _buffer->header.cacheType          = _options.optimizeStubs ? kDyldSharedCacheTypeProduction : kDyldSharedCacheTypeDevelopment;
+    _buffer->header.accelerateInfoAddr = 0;
+    _buffer->header.accelerateInfoSize = 0;
+    bzero(_buffer->header.uuid, 16);    // overwritten later by recomputeCacheUUID()
+    _buffer->header.branchPoolsOffset    = _buffer->header.mappingOffset + 3*sizeof(dyld_cache_mapping_info);
+    _buffer->header.branchPoolsCount     = (uint32_t)_branchPoolStarts.size();
+    _buffer->header.imagesTextOffset     = _buffer->header.imagesOffset + sizeof(dyld_cache_image_info)*_buffer->header.imagesCount;
+    _buffer->header.imagesTextCount      = dylibs.size();
+    _buffer->header.platform             = (uint8_t)_options.platform;
+    _buffer->header.formatVersion        = dyld3::launch_cache::binary_format::kFormatVersion;
+    _buffer->header.dylibsExpectedOnDisk = !_options.dylibsRemovedDuringMastering;
+    _buffer->header.simulator            = _options.forSimulator;
+
+    // fill in mappings
+    dyld_cache_mapping_info* mappings = (dyld_cache_mapping_info*)((char*)_buffer + _buffer->header.mappingOffset);
+    mappings[0] = regions[0];
+    mappings[1] = regions[1];
+    mappings[2] = regions[2];
+
+    // fill in branch pool addresses
+    uint64_t* p = (uint64_t*)((char*)_buffer + _buffer->header.branchPoolsOffset);
+    for (uint64_t pool : _branchPoolStarts) {
+        *p++ = pool;
+    }
+
+    // fill in image table
+    dyld_cache_image_info* images = (dyld_cache_image_info*)((char*)_buffer + _buffer->header.imagesOffset);
+    for (const DyldSharedCache::MappedMachO& dylib : dylibs) {
+        const std::vector<SegmentMappingInfo>& segs = segmentMappings.at(dylib.mh);
+        dyld3::MachOParser parser(dylib.mh);
+        const char* installName = parser.installName();
+        images->address = segs[0].dstCacheAddress;
+        if ( _options.dylibsRemovedDuringMastering ) {
+            images->modTime = 0;
+            images->inode   = pathHash(installName);
+        }
+        else {
+            images->modTime = dylib.modTime;
+            images->inode   = dylib.inode;
+        }
+        uint32_t installNameOffsetInTEXT =  (uint32_t)(installName - (char*)dylib.mh);
+        images->pathFileOffset = (uint32_t)segs[0].dstCacheOffset + installNameOffsetInTEXT;
+        ++images;
+    }
+    // append aliases image records and strings
+/*
+    for (auto &dylib : _dylibs) {
+        if (!dylib->installNameAliases.empty()) {
+            for (const std::string& alias : dylib->installNameAliases) {
+                images->set_address(_segmentMap[dylib][0].address);
+                if (_manifest.platform() == "osx") {
+                    images->modTime = dylib->lastModTime;
+                    images->inode = dylib->inode;
+                }
+                else {
+                    images->modTime = 0;
+                    images->inode = pathHash(alias.c_str());
+                }
+                images->pathFileOffset = offset;
+                //fprintf(stderr, "adding alias %s for %s\n", alias.c_str(), dylib->installName.c_str());
+                ::strcpy((char*)&_buffer[offset], alias.c_str());
+                offset += alias.size() + 1;
+                ++images;
+            }
+        }
+    }
+*/
+    // calculate start of text image array and trailing string pool
+    dyld_cache_image_text_info* textImages = (dyld_cache_image_text_info*)((char*)_buffer + _buffer->header.imagesTextOffset);
+    uint32_t stringOffset = (uint32_t)(_buffer->header.imagesTextOffset + sizeof(dyld_cache_image_text_info) * dylibs.size());
+
+    // write text image array and image names pool at same time
+    for (const DyldSharedCache::MappedMachO& dylib : dylibs) {
+        const std::vector<SegmentMappingInfo>& segs = segmentMappings.at(dylib.mh);
+        dyld3::MachOParser parser(dylib.mh);
+        parser.getUuid(textImages->uuid);
+        textImages->loadAddress     = segs[0].dstCacheAddress;
+        textImages->textSegmentSize = (uint32_t)segs[0].dstCacheSegmentSize;
+        textImages->pathOffset      = stringOffset;
+        const char* installName = parser.installName();
+        ::strcpy((char*)_buffer + stringOffset, installName);
+        stringOffset += (uint32_t)strlen(installName)+1;
+        ++textImages;
+    }
+
+    // make sure header did not overflow into first mapped image
+    const dyld_cache_image_info* firstImage = (dyld_cache_image_info*)((char*)_buffer + _buffer->header.imagesOffset);
+    assert(stringOffset <= (firstImage->address - mappings[0].address));
+}
+
+
+void CacheBuilder::copyRawSegments(const std::vector<DyldSharedCache::MappedMachO>& dylibs, const SegmentMapping& mapping)
+{
+    uint8_t* cacheBytes = (uint8_t*)_buffer;
+    for (const DyldSharedCache::MappedMachO& dylib : dylibs) {
+        auto pos = mapping.find(dylib.mh);
+        assert(pos != mapping.end());
+        for (const SegmentMappingInfo& info : pos->second) {
+            //fprintf(stderr, "copy %s segment %s (0x%08X bytes) from %p to %p (logical addr 0x%llX) for %s\n", _options.archName.c_str(), info.segName, info.copySegmentSize, info.srcSegment, &cacheBytes[info.dstCacheOffset], info.dstCacheAddress, dylib.runtimePath.c_str());
+            ::memcpy(&cacheBytes[info.dstCacheOffset], info.srcSegment, info.copySegmentSize);
+        }
+    }
+}
+
+void CacheBuilder::adjustAllImagesForNewSegmentLocations(const std::vector<DyldSharedCache::MappedMachO>& dylibs, const SegmentMapping& mapping)
+{
+    uint8_t* cacheBytes = (uint8_t*)_buffer;
+    for (const DyldSharedCache::MappedMachO& dylib : dylibs) {
+        auto pos = mapping.find(dylib.mh);
+        assert(pos != mapping.end());
+        mach_header* mhInCache = (mach_header*)&cacheBytes[pos->second[0].dstCacheOffset];
+        adjustDylibSegments(_buffer, _archLayout->is64, mhInCache, pos->second, _pointersForASLR, _diagnostics);
+        if ( _diagnostics.hasError() )
+            break;
+    }
+}
+
+struct Counts {
+    unsigned long lazyCount    = 0;
+    unsigned long nonLazyCount = 0;
+};
+
+void CacheBuilder::bindAllImagesInCacheFile(const dyld_cache_mapping_info regions[3])
 {
     const bool log = false;
-    const bool logCFConstants = false;
-
-    forEachDylibInfo(^(const DylibInfo& dylib, Diagnostics& dylibDiag) {
-        for (const SegmentMappingInfo& info : dylib.cacheLocation) {
-            if (log) fprintf(stderr, "copy %s segment %s (0x%08X bytes) from %p to %p (logical addr 0x%llX) for %s\n",
-                             _options.archs->name(), info.segName, info.copySegmentSize, info.srcSegment, info.dstSegment, info.dstCacheUnslidAddress, dylib.input->mappedFile.runtimePath.c_str());
-            ::memcpy(info.dstSegment, info.srcSegment, info.copySegmentSize);
-        }
+    __block std::unordered_map<std::string, Counts> useCounts;
+
+    // build map of install names to mach_headers
+    __block std::unordered_map<std::string, const mach_header*> installNameToMH;
+    __block std::vector<const mach_header*> dylibMHs;
+    _buffer->forEachImage(^(const mach_header* mh, const char* installName) {
+        installNameToMH[installName] = mh;
+        dylibMHs.push_back(mh);
     });
 
-    // Copy the coalesced __TEXT sections
-    const uint64_t numCoalescedSections = sizeof(CacheCoalescedText::SupportedSections) / sizeof(*CacheCoalescedText::SupportedSections);
-    dispatch_apply(numCoalescedSections, DISPATCH_APPLY_AUTO, ^(size_t index) {
-        const CacheCoalescedText::StringSection& cacheStringSection = _coalescedText.getSectionData(CacheCoalescedText::SupportedSections[index]);
-        if (log) fprintf(stderr, "copy %s __TEXT_COAL section %s (0x%08X bytes) to %p (logical addr 0x%llX)\n",
-                         _options.archs->name(), CacheCoalescedText::SupportedSections[index],
-                         cacheStringSection.bufferSize, cacheStringSection.bufferAddr, cacheStringSection.bufferVMAddr);
-        for (const auto& stringAndOffset : cacheStringSection.stringsToOffsets)
-            ::memcpy(cacheStringSection.bufferAddr + stringAndOffset.second, stringAndOffset.first.data(), stringAndOffset.first.size() + 1);
+    __block Diagnostics parsingDiag;
+    bool (^dylibFinder)(uint32_t, const char*, void* , const mach_header**, void**) = ^(uint32_t depIndex, const char* depLoadPath, void* extra, const mach_header** foundMH, void** foundExtra) {
+        auto pos = installNameToMH.find(depLoadPath);
+        if ( pos != installNameToMH.end() ) {
+            *foundMH = pos->second;
+            *foundExtra = nullptr;
+            return true;
+        }
+        parsingDiag.error("dependent dylib %s not found", depLoadPath);
+        return false;
+    };
+    if ( parsingDiag.hasError() ) {
+        _diagnostics.error("%s", parsingDiag.errorMessage().c_str());
+        return;
+    }
+
+    // bind every dylib in cache
+    for (const mach_header* mh : dylibMHs) {
+        dyld3::MachOParser parser(mh, true);
+        bool is64 = parser.is64();
+        const char* depPaths[256];
+        const char** depPathsArray = depPaths;
+        __block int depIndex = 1;
+        parser.forEachDependentDylib(^(const char* loadPath, bool isWeak, bool isReExport, bool isUpward, uint32_t compatVersion, uint32_t curVersion, bool& stop) {
+            depPathsArray[depIndex++] = loadPath;
+        });
+        uint8_t*  segCacheStarts[10];
+        uint64_t  segCacheAddrs[10];
+        uint8_t** segCacheStartsArray = segCacheStarts;
+        uint64_t* segCacheAddrsArray  = segCacheAddrs;
+        __block int segIndex = 0;
+        parser.forEachSegment(^(const char* segName, uint32_t fileOffset, uint32_t fileSize, uint64_t vmAddr, uint64_t vmSize, uint8_t protections, bool& stop) {
+             segCacheStartsArray[segIndex] = (segIndex == 0) ? (uint8_t*)mh : (uint8_t*)_buffer + fileOffset;
+             segCacheAddrsArray[segIndex] = vmAddr;
+             ++segIndex;
+        });
+        __block Diagnostics bindingDiag;
+        parser.forEachBind(bindingDiag, ^(uint32_t dataSegIndex, uint64_t dataSegOffset, uint8_t type, int libOrdinal, uint64_t addend, const char* symbolName, bool weakImport, bool lazy, bool& stop) {
+            if ( log ) {
+                if ( lazy )
+                    useCounts[symbolName].lazyCount += 1;
+                else
+                    useCounts[symbolName].nonLazyCount += 1;
+            }
+            const mach_header* targetMH = nullptr;
+            if ( libOrdinal == BIND_SPECIAL_DYLIB_SELF ) {
+                targetMH = mh;
+            }
+            else if ( libOrdinal == BIND_SPECIAL_DYLIB_MAIN_EXECUTABLE ) {
+                parsingDiag.error("bind ordinal BIND_SPECIAL_DYLIB_MAIN_EXECUTABLE not supported in dylibs in dyld shared cache (found in %s)", parser.installName());
+                stop = true;
+                return;
+            }
+            else if ( libOrdinal == BIND_SPECIAL_DYLIB_FLAT_LOOKUP ) {
+                parsingDiag.error("bind ordinal BIND_SPECIAL_DYLIB_FLAT_LOOKUP not supported in dylibs in dyld shared cache (found in %s)", parser.installName());
+                stop = true;
+                return;
+            }
+            else {
+                const char* fromPath = depPathsArray[libOrdinal];
+                auto pos = installNameToMH.find(fromPath);
+                if (pos == installNameToMH.end()) {
+                    if (!weakImport) {
+                        _diagnostics.error("dependent dylib %s not found", fromPath);
+                    }
+                    return;
+                }
+                targetMH = pos->second;
+            }
+            dyld3::MachOParser targetParser(targetMH, true);
+            dyld3::MachOParser::FoundSymbol foundInfo;
+            uint64_t targetValue = 0;
+            uint8_t* fixupLoc = segCacheStartsArray[dataSegIndex] + dataSegOffset;
+            if ( targetParser.findExportedSymbol(parsingDiag, symbolName, nullptr, foundInfo, dylibFinder) ) {
+                const mach_header* foundInMH = foundInfo.foundInDylib;
+                dyld3::MachOParser foundInParser(foundInMH, true);
+                uint64_t foundInBaseAddress = foundInParser.preferredLoadAddress();
+                switch ( foundInfo.kind ) {
+                    case dyld3::MachOParser::FoundSymbol::Kind::resolverOffset:
+                        // Bind to the target stub for resolver based functions.
+                        // There may be a later optimization to alter the client
+                        // stubs to directly to the target stub's lazy pointer.
+                    case dyld3::MachOParser::FoundSymbol::Kind::headerOffset:
+                        targetValue = foundInBaseAddress + foundInfo.value + addend;
+                        _pointersForASLR.push_back((void*)fixupLoc);
+                        if ( foundInMH != mh ) {
+                            uint32_t mhVmOffset                 = (uint32_t)((uint8_t*)foundInMH - (uint8_t*)_buffer);
+                            uint32_t definitionCacheVmOffset    = (uint32_t)(mhVmOffset + foundInfo.value);
+                            uint32_t referenceCacheDataVmOffset = (uint32_t)(segCacheAddrsArray[dataSegIndex] + dataSegOffset - regions[1].address);
+                            assert(referenceCacheDataVmOffset < (1<<30));
+                            dyld3::launch_cache::binary_format::PatchOffset entry;
+                            entry.last              = false;
+                            entry.hasAddend         = (addend != 0);
+                            entry.dataRegionOffset  = referenceCacheDataVmOffset;
+                            _patchTable[foundInMH][definitionCacheVmOffset].insert(*((uint32_t*)&entry));
+                        }
+                       break;
+                    case dyld3::MachOParser::FoundSymbol::Kind::absolute:
+                        // pointers set to absolute values are not slid
+                        targetValue = foundInfo.value + addend;
+                        break;
+                }
+            }
+            else if ( weakImport ) {
+                // weak pointers set to zero are not slid
+                targetValue = 0;
+            }
+            else {
+                parsingDiag.error("cannot find symbol %s, needed in dylib %s", symbolName, parser.installName());
+                stop = true;
+            }
+            switch ( type ) {
+                case BIND_TYPE_POINTER:
+                    if ( is64 )
+                        *((uint64_t*)fixupLoc) = targetValue;
+                    else
+                        *((uint32_t*)fixupLoc) = (uint32_t)targetValue;
+                    break;
+                case BIND_TYPE_TEXT_ABSOLUTE32:
+                case BIND_TYPE_TEXT_PCREL32:
+                    parsingDiag.error("text relocs not supported for shared cache binding in %s", parser.installName());
+                    stop = true;
+                    break;
+                default:
+                    parsingDiag.error("bad bind type (%d) in %s", type, parser.installName());
+                    stop = true;
+                    break;
+
+            }
+        });
+        if ( bindingDiag.hasError() ) {
+            parsingDiag.error("%s in dylib %s", bindingDiag.errorMessage().c_str(), parser.installName());
+        }
+        if ( parsingDiag.hasError() )
+            break;
+        // also need to add patch locations for weak-binds that point within same image, since they are not captured by binds above
+        parser.forEachWeakDef(bindingDiag, ^(bool strongDef, uint32_t dataSegIndex, uint64_t dataSegOffset, uint64_t addend, const char* symbolName, bool &stop) {
+            if ( strongDef )
+                return;
+            uint8_t* fixupLoc = segCacheStartsArray[dataSegIndex] + dataSegOffset;
+            dyld3::MachOParser::FoundSymbol weakFoundInfo;
+            Diagnostics weakLookupDiag;
+            if ( parser.findExportedSymbol(weakLookupDiag, symbolName, nullptr, weakFoundInfo, nullptr) ) {
+                // this is an interior pointing (rebased) pointer
+                uint64_t targetValue;
+                if ( is64 )
+                    targetValue = *((uint64_t*)fixupLoc);
+                else
+                    targetValue = *((uint32_t*)fixupLoc);
+                uint32_t definitionCacheVmOffset    = (uint32_t)(targetValue - regions[0].address);
+                uint32_t referenceCacheDataVmOffset = (uint32_t)(segCacheAddrsArray[dataSegIndex] + dataSegOffset - regions[1].address);
+                assert(referenceCacheDataVmOffset < (1<<30));
+                dyld3::launch_cache::binary_format::PatchOffset entry;
+                entry.last              = false;
+                entry.hasAddend         = (addend != 0);
+                entry.dataRegionOffset  = referenceCacheDataVmOffset;
+                _patchTable[mh][definitionCacheVmOffset].insert(*((uint32_t*)&entry));
+            }
+        });
+        if ( bindingDiag.hasError() ) {
+            parsingDiag.error("%s in dylib %s", bindingDiag.errorMessage().c_str(), parser.installName());
+        }
+        if ( parsingDiag.hasError() )
+            break;
+    }
+
+    if ( log ) {
+        unsigned lazyCount = 0;
+        unsigned nonLazyCount = 0;
+        std::unordered_set<std::string> lazyTargets;
+        for (auto entry : useCounts) {
+            fprintf(stderr, "% 3ld      % 3ld     %s\n", entry.second.lazyCount, entry.second.nonLazyCount, entry.first.c_str());
+            lazyCount += entry.second.lazyCount;
+            nonLazyCount += entry.second.nonLazyCount;
+            if ( entry.second.lazyCount != 0 )
+                lazyTargets.insert(entry.first);
+        }
+        fprintf(stderr, "lazyCount = %d\n", lazyCount);
+        fprintf(stderr, "nonLazyCount = %d\n", nonLazyCount);
+        fprintf(stderr, "unique lazys = %ld\n", lazyTargets.size());
+    }
+    
+    if ( parsingDiag.hasError() )
+        _diagnostics.error("%s", parsingDiag.errorMessage().c_str());
+}
+
+
+void CacheBuilder::recomputeCacheUUID(void)
+{
+    // Clear existing UUID, then MD5 whole cache buffer.
+    uint8_t* uuidLoc = _buffer->header.uuid;
+    bzero(uuidLoc, 16);
+    CC_MD5(_buffer, (unsigned)_currentFileSize, uuidLoc);
+    // <rdar://problem/6723729> uuids should conform to RFC 4122 UUID version 4 & UUID version 5 formats
+    uuidLoc[6] = ( uuidLoc[6] & 0x0F ) | ( 3 << 4 );
+    uuidLoc[8] = ( uuidLoc[8] & 0x3F ) | 0x80;
+}
+
+
+CacheBuilder::SegmentMapping CacheBuilder::assignSegmentAddresses(const std::vector<DyldSharedCache::MappedMachO>& dylibs, dyld_cache_mapping_info regions[3])
+{
+    // calculate size of header info and where first dylib's mach_header should start
+    size_t startOffset = sizeof(dyld_cache_header) + 3*sizeof(dyld_cache_mapping_info);
+    size_t maxPoolCount = 0;
+    if (  _archLayout->branchReach != 0 )
+        maxPoolCount = (_archLayout->sharedMemorySize / _archLayout->branchReach);
+    startOffset += maxPoolCount * sizeof(uint64_t);
+    startOffset += sizeof(dyld_cache_image_info) * dylibs.size();
+    startOffset += sizeof(dyld_cache_image_text_info) * dylibs.size();
+    for (const DyldSharedCache::MappedMachO& dylib : dylibs) {
+        dyld3::MachOParser parser(dylib.mh);
+        startOffset += (strlen(parser.installName()) + 1);
+    }
+    //fprintf(stderr, "%s total header size = 0x%08lX\n", _options.archName.c_str(), startOffset);
+    startOffset = align(startOffset, 12);
+
+    _branchPoolStarts.clear();
+    __block uint64_t addr = _archLayout->sharedMemoryStart;
+    __block SegmentMapping result;
+
+    // assign TEXT segment addresses
+    regions[0].address      = addr;
+    regions[0].fileOffset   = 0;
+    regions[0].initProt     = VM_PROT_READ | VM_PROT_EXECUTE;
+    regions[0].maxProt      = VM_PROT_READ | VM_PROT_EXECUTE;
+    addr += startOffset; // header
+
+    __block uint64_t lastPoolAddress = addr;
+    for (const DyldSharedCache::MappedMachO& dylib : dylibs) {
+        dyld3::MachOParser parser(dylib.mh, true);
+        parser.forEachSegment(^(const char* segName, uint32_t fileOffset, uint32_t fileSize, uint64_t vmAddr, uint64_t vmSize, uint8_t protections, uint32_t segIndex, uint64_t sizeOfSections, uint8_t p2align, bool& stop) {
+             if ( protections != (VM_PROT_READ | VM_PROT_EXECUTE) )
+                return;
+            // Insert branch island pools every 128MB for arm64
+            if ( (_archLayout->branchPoolTextSize != 0) && ((addr + vmSize - lastPoolAddress) > _archLayout->branchReach) ) {
+                _branchPoolStarts.push_back(addr);
+                _diagnostics.verbose("adding branch pool at 0x%llX\n", addr);
+                lastPoolAddress = addr;
+                addr += _archLayout->branchPoolTextSize;
+            }
+            // Keep __TEXT segments 4K or more aligned
+            addr = align(addr, std::max(p2align, (uint8_t)12));
+            SegmentMappingInfo info;
+            info.srcSegment          = (uint8_t*)dylib.mh + fileOffset;
+            info.segName             = segName;
+            info.dstCacheAddress     = addr;
+            info.dstCacheOffset      = (uint32_t)(addr - regions[0].address + regions[0].fileOffset);
+            info.dstCacheSegmentSize = (uint32_t)align(sizeOfSections, 12);
+            info.copySegmentSize     = (uint32_t)align(sizeOfSections, 12);
+            info.srcSegmentIndex     = segIndex;
+            result[dylib.mh].push_back(info);
+            addr += info.dstCacheSegmentSize;
+        });
+    }
+    // align TEXT region end
+    uint64_t endTextAddress = align(addr, _archLayout->sharedRegionAlignP2);
+    regions[0].size         = endTextAddress - regions[0].address;
+
+    // assign __DATA* addresses
+    if ( _archLayout->sharedRegionsAreDiscontiguous )
+        addr = _archLayout->sharedMemoryStart + 0x60000000;
+    else
+        addr = align((addr + _archLayout->sharedRegionPadding), _archLayout->sharedRegionAlignP2);
+    regions[1].address      = addr;
+    regions[1].fileOffset   = regions[0].fileOffset + regions[0].size;
+    regions[1].initProt     = VM_PROT_READ | VM_PROT_WRITE;
+    regions[1].maxProt      = VM_PROT_READ | VM_PROT_WRITE;
+
+    // layout all __DATA_CONST segments
+    __block int dataConstSegmentCount = 0;
+    for (const DyldSharedCache::MappedMachO& dylib : dylibs) {
+        dyld3::MachOParser parser(dylib.mh, true);
+        parser.forEachSegment(^(const char* segName, uint32_t fileOffset, uint32_t fileSize, uint64_t vmAddr, uint64_t vmSize, uint8_t protections, uint32_t segIndex, uint64_t sizeOfSections, uint8_t p2align, bool& stop) {
+            if ( protections != (VM_PROT_READ | VM_PROT_WRITE) )
+                return;
+            if ( strcmp(segName, "__DATA_CONST") != 0 )
+                return;
+            ++dataConstSegmentCount;
+            // Pack __DATA_CONST segments
+            addr = align(addr, p2align);
+            size_t copySize = std::min((size_t)fileSize, (size_t)sizeOfSections);
+            SegmentMappingInfo info;
+            info.srcSegment          = (uint8_t*)dylib.mh + fileOffset;
+            info.segName             = segName;
+            info.dstCacheAddress     = addr;
+            info.dstCacheOffset      = (uint32_t)(addr - regions[1].address + regions[1].fileOffset);
+            info.dstCacheSegmentSize = (uint32_t)sizeOfSections;
+            info.copySegmentSize     = (uint32_t)copySize;
+            info.srcSegmentIndex     = segIndex;
+            result[dylib.mh].push_back(info);
+            addr += info.dstCacheSegmentSize;
+        });
+    }
+
+    // layout all __DATA segments (and other r/w non-dirty, non-const) segments
+    for (const DyldSharedCache::MappedMachO& dylib : dylibs) {
+        dyld3::MachOParser parser(dylib.mh, true);
+        parser.forEachSegment(^(const char* segName, uint32_t fileOffset, uint32_t fileSize, uint64_t vmAddr, uint64_t vmSize, uint8_t protections, uint32_t segIndex, uint64_t sizeOfSections, uint8_t p2align, bool& stop) {
+            if ( protections != (VM_PROT_READ | VM_PROT_WRITE) )
+                return;
+            if ( strcmp(segName, "__DATA_CONST") == 0 )
+                return;
+            if ( strcmp(segName, "__DATA_DIRTY") == 0 )
+                return;
+            if ( dataConstSegmentCount > 10 ) {
+                // Pack __DATA segments only if we also have __DATA_CONST segments
+                addr = align(addr, p2align);
+            }
+            else {
+                // Keep __DATA segments 4K or more aligned
+                addr = align(addr, std::max(p2align, (uint8_t)12));
+            }
+            size_t copySize = std::min((size_t)fileSize, (size_t)sizeOfSections);
+            SegmentMappingInfo info;
+            info.srcSegment          = (uint8_t*)dylib.mh + fileOffset;
+            info.segName             = segName;
+            info.dstCacheAddress     = addr;
+            info.dstCacheOffset      = (uint32_t)(addr - regions[1].address + regions[1].fileOffset);
+            info.dstCacheSegmentSize = (uint32_t)sizeOfSections;
+            info.copySegmentSize     = (uint32_t)copySize;
+            info.srcSegmentIndex     = segIndex;
+            result[dylib.mh].push_back(info);
+            addr += info.dstCacheSegmentSize;
+        });
+    }
+
+    // layout all __DATA_DIRTY segments, sorted
+    addr = align(addr, 12);
+    std::vector<DyldSharedCache::MappedMachO> dirtyDataDylibs = makeSortedDylibs(dylibs, _options.dirtyDataSegmentOrdering);
+    for (const DyldSharedCache::MappedMachO& dylib : dirtyDataDylibs) {
+        dyld3::MachOParser parser(dylib.mh, true);
+        parser.forEachSegment(^(const char* segName, uint32_t fileOffset, uint32_t fileSize, uint64_t vmAddr, uint64_t vmSize, uint8_t protections, uint32_t segIndex, uint64_t sizeOfSections, uint8_t p2align, bool& stop) {
+            if ( protections != (VM_PROT_READ | VM_PROT_WRITE) )
+                return;
+            if ( strcmp(segName, "__DATA_DIRTY") != 0 )
+                return;
+            // Pack __DATA_DIRTY segments
+            addr = align(addr, p2align);
+            size_t copySize = std::min((size_t)fileSize, (size_t)sizeOfSections);
+            SegmentMappingInfo info;
+            info.srcSegment          = (uint8_t*)dylib.mh + fileOffset;
+            info.segName             = segName;
+            info.dstCacheAddress     = addr;
+            info.dstCacheOffset      = (uint32_t)(addr - regions[1].address + regions[1].fileOffset);
+            info.dstCacheSegmentSize = (uint32_t)sizeOfSections;
+            info.copySegmentSize     = (uint32_t)copySize;
+            info.srcSegmentIndex     = segIndex;
+            result[dylib.mh].push_back(info);
+            addr += info.dstCacheSegmentSize;
+        });
+    }
+
+    // align DATA region end
+    uint64_t endDataAddress = align(addr, _archLayout->sharedRegionAlignP2);
+    regions[1].size         = endDataAddress - regions[1].address;
+
+    // start read-only region
+    if ( _archLayout->sharedRegionsAreDiscontiguous )
+        addr = _archLayout->sharedMemoryStart + 0xA0000000;
+    else
+        addr = align((addr + _archLayout->sharedRegionPadding), _archLayout->sharedRegionAlignP2);
+    regions[2].address    = addr;
+    regions[2].fileOffset = regions[1].fileOffset + regions[1].size;
+    regions[2].maxProt    = VM_PROT_READ;
+    regions[2].initProt   = VM_PROT_READ;
+
+    // reserve space for kernel ASLR slide info at start of r/o region
+    if ( _options.cacheSupportsASLR ) {
+        _slideInfoBufferSizeAllocated = align((regions[1].size/4096) * 4, _archLayout->sharedRegionAlignP2); // only need 2 bytes per page
+        _slideInfoFileOffset = regions[2].fileOffset;
+        addr += _slideInfoBufferSizeAllocated;
+    }
+
+    // layout all read-only (but not LINKEDIT) segments
+    for (const DyldSharedCache::MappedMachO& dylib : dylibs) {
+        dyld3::MachOParser parser(dylib.mh, true);
+        parser.forEachSegment(^(const char* segName, uint32_t fileOffset, uint32_t fileSize, uint64_t vmAddr, uint64_t vmSize, uint8_t protections, uint32_t segIndex, uint64_t sizeOfSections, uint8_t p2align, bool& stop) {
+            if ( protections != VM_PROT_READ )
+                return;
+            if ( strcmp(segName, "__LINKEDIT") == 0 )
+                return;
+            // Keep segments segments 4K or more aligned
+            addr = align(addr, std::max(p2align, (uint8_t)12));
+            SegmentMappingInfo info;
+            info.srcSegment          = (uint8_t*)dylib.mh + fileOffset;
+            info.segName             = segName;
+            info.dstCacheAddress     = addr;
+            info.dstCacheOffset      = (uint32_t)(addr - regions[2].address + regions[2].fileOffset);
+            info.dstCacheSegmentSize = (uint32_t)align(sizeOfSections, 12);
+            info.copySegmentSize     = (uint32_t)sizeOfSections;
+            info.srcSegmentIndex     = segIndex;
+            result[dylib.mh].push_back(info);
+            addr += info.dstCacheSegmentSize;
+        });
+    }
+    // layout all LINKEDIT segments (after other read-only segments)
+    for (const DyldSharedCache::MappedMachO& dylib : dylibs) {
+        dyld3::MachOParser parser(dylib.mh, true);
+        parser.forEachSegment(^(const char* segName, uint32_t fileOffset, uint32_t fileSize, uint64_t vmAddr, uint64_t vmSize, uint8_t protections, uint32_t segIndex, uint64_t sizeOfSections, uint8_t p2align, bool& stop) {
+            if ( protections != VM_PROT_READ )
+                return;
+            if ( strcmp(segName, "__LINKEDIT") != 0 )
+                return;
+            // Keep segments segments 4K or more aligned
+            addr = align(addr, std::max(p2align, (uint8_t)12));
+            SegmentMappingInfo info;
+            info.srcSegment          = (uint8_t*)dylib.mh + fileOffset;
+            info.segName             = segName;
+            info.dstCacheAddress     = addr;
+            info.dstCacheOffset      = (uint32_t)(addr - regions[2].address + regions[2].fileOffset);
+            info.dstCacheSegmentSize = (uint32_t)align(sizeOfSections, 12);
+            info.copySegmentSize     = (uint32_t)align(fileSize, 12);
+            info.srcSegmentIndex     = segIndex;
+            result[dylib.mh].push_back(info);
+            addr += info.dstCacheSegmentSize;
+        });
+    }
+    // add room for branch pool linkedits
+    _branchPoolsLinkEditStartAddr = addr;
+    addr += (_branchPoolStarts.size() * _archLayout->branchPoolLinkEditSize);
+
+    // align r/o region end
+    uint64_t endReadOnlyAddress = align(addr, _archLayout->sharedRegionAlignP2);
+    regions[2].size = endReadOnlyAddress - regions[2].address;
+    _currentFileSize = regions[2].fileOffset + regions[2].size;
+
+    // FIXME: Confirm these numbers for all platform/arch combos
+    // assume LINKEDIT optimzation reduces LINKEDITs to %40 of original size
+    if ( _options.excludeLocalSymbols ) {
+        _vmSize = regions[2].address + (regions[2].size * 2 / 5) - regions[0].address;
+    }
+    else {
+        _vmSize = regions[2].address + (regions[2].size * 9 / 10) - regions[0].address;
+    }
+
+    // sort SegmentMappingInfo for each image to be in the same order as original segments
+    for (auto& entry : result) {
+        std::vector<SegmentMappingInfo>& infos = entry.second;
+        std::sort(infos.begin(), infos.end(), [&](const SegmentMappingInfo& a, const SegmentMappingInfo& b) {
+            return a.srcSegmentIndex < b.srcSegmentIndex;
+        });
+    }
+
+    return result;
+}
+
+uint64_t CacheBuilder::pathHash(const char* path)
+{
+    uint64_t sum = 0;
+    for (const char* s=path; *s != '\0'; ++s)
+        sum += sum*4 + *s;
+    return sum;
+}
+
+
+void CacheBuilder::findDylibAndSegment(const void* contentPtr, std::string& foundDylibName, std::string& foundSegName)
+{
+    foundDylibName = "???";
+    foundSegName   = "???";
+    uint32_t cacheOffset = (uint32_t)((uint8_t*)contentPtr - (uint8_t*)_buffer);
+    _buffer->forEachImage(^(const mach_header* mh, const char* installName) {
+        dyld3::MachOParser parser(mh, true);
+        parser.forEachSegment(^(const char* segName, uint32_t fileOffset, uint32_t fileSize, uint64_t vmAddr, uint64_t vmSize, uint8_t protections, bool& stop) {
+            if ( (cacheOffset > fileOffset) && (cacheOffset < (fileOffset+vmSize)) ) {
+                foundDylibName = installName;
+                foundSegName = segName;
+            }
+        });
     });
-
-    // Copy the coalesced CF sections
-    if ( _coalescedText.cfStrings.bufferSize != 0 ) {
-        uint8_t* dstBuffer = _coalescedText.cfStrings.bufferAddr;
-        uint64_t dstBufferVMAddr = _coalescedText.cfStrings.bufferVMAddr;
-        forEachDylibInfo(^(const DylibInfo& dylib, Diagnostics& dylibDiag) {
-            const char* segmentName = "__OBJC_CONST";
-            const char* sectionName = "__cfstring";
-            const DylibTextCoalescer::DylibSectionOffsetToCacheSectionOffset& sectionData = dylib.textCoalescer.getSectionCoalescer(segmentName, sectionName);
-            if ( sectionData.empty() )
-                return;
-
-            uint64_t sectionContentSize = 0;
-            const void* sectionContent = dylib.input->mappedFile.mh->findSectionContent(segmentName, sectionName, sectionContentSize);
-            assert(sectionContent != nullptr);
-            assert(sectionContentSize != 0);
-            for (const auto& dylibOffsetAndCacheOffset : sectionData) {
-                uint64_t dylibOffset = dylibOffsetAndCacheOffset.first;
-                uint64_t cacheOffset = dylibOffsetAndCacheOffset.second;
-                if (logCFConstants) fprintf(stderr, "copy %s %s section %s (0x%08X bytes) to %p (logical addr 0x%llX)\n",
-                                            _options.archs->name(), segmentName, sectionName,
-                                            (uint32_t)DyldSharedCache::ConstantClasses::cfStringAtomSize, dstBuffer + cacheOffset, dstBufferVMAddr + cacheOffset);
-                ::memcpy(dstBuffer + cacheOffset, (const uint8_t*)sectionContent + dylibOffset, (size_t)DyldSharedCache::ConstantClasses::cfStringAtomSize);
-            }
-        });
-    }
-}
-
-void CacheBuilder::adjustAllImagesForNewSegmentLocations(uint64_t cacheBaseAddress,
-                                                         ASLR_Tracker& aslrTracker, LOH_Tracker* lohTracker,
-                                                         const CacheBuilder::CacheCoalescedText* coalescedText)
-{
-    // Note this cannot to be done in parallel because the LOH Tracker and aslr tracker are not thread safe
-    __block bool badDylib = false;
-    forEachDylibInfo(^(const DylibInfo& dylib, Diagnostics& dylibDiag) {
-        if ( dylibDiag.hasError() )
-            return;
-        adjustDylibSegments(dylib, dylibDiag, cacheBaseAddress, aslrTracker,
-                            lohTracker, coalescedText);
-        if ( dylibDiag.hasError() )
-            badDylib = true;
-    });
-
-    if ( badDylib && !_diagnostics.hasError() ) {
-        _diagnostics.error("One or more binaries has an error which prevented linking.  See other errors.");
-    }
-}
-
-
-CacheBuilder::ASLR_Tracker::~ASLR_Tracker()
-{
-    if ( _bitmap != nullptr )
-        ::free(_bitmap);
-#if BUILDING_APP_CACHE_UTIL
-    if ( _cacheLevels != nullptr )
-        ::free(_cacheLevels);
-#endif
-}
-
-void CacheBuilder::ASLR_Tracker::setDataRegion(const void* rwRegionStart, size_t rwRegionSize)
-{
-    _pageCount   = (unsigned)(rwRegionSize+_pageSize-1)/_pageSize;
-    _regionStart = (uint8_t*)rwRegionStart;
-    _regionEnd   = (uint8_t*)rwRegionStart + rwRegionSize;
-    _bitmap      = (bool*)calloc(_pageCount*(_pageSize/kMinimumFixupAlignment)*sizeof(bool), 1);
-#if BUILDING_APP_CACHE_UTIL
-    size_t cacheLevelsSize = (_pageCount*(_pageSize/kMinimumFixupAlignment)*sizeof(uint8_t));
-    _cacheLevels = (uint8_t*)malloc(cacheLevelsSize);
-    memset(_cacheLevels, (int)~0U, cacheLevelsSize);
-#endif
-}
-
-void CacheBuilder::ASLR_Tracker::add(void* loc, uint8_t level)
-{
-    if (!_enabled)
-        return;
-    uint8_t* p = (uint8_t*)loc;
-    assert(p >= _regionStart);
-    assert(p < _regionEnd);
-    _bitmap[(p-_regionStart)/kMinimumFixupAlignment] = true;
-
-#if BUILDING_APP_CACHE_UTIL
-    if ( level != (uint8_t)~0U ) {
-        _cacheLevels[(p-_regionStart)/kMinimumFixupAlignment] = level;
-    }
-#endif
-}
-
-void CacheBuilder::ASLR_Tracker::remove(void* loc)
-{
-    if (!_enabled)
-        return;
-    uint8_t* p = (uint8_t*)loc;
-    assert(p >= _regionStart);
-    assert(p < _regionEnd);
-    _bitmap[(p-_regionStart)/kMinimumFixupAlignment] = false;
-}
-
-bool CacheBuilder::ASLR_Tracker::has(void* loc, uint8_t* level) const
-{
-    if (!_enabled)
+ }
+
+
+template <typename P>
+bool CacheBuilder::makeRebaseChain(uint8_t* pageContent, uint16_t lastLocationOffset, uint16_t offset, const dyld_cache_slide_info2* info)
+{
+    typedef typename P::uint_t     pint_t;
+
+    const pint_t   deltaMask    = (pint_t)(info->delta_mask);
+    const pint_t   valueMask    = ~deltaMask;
+    const pint_t   valueAdd     = (pint_t)(info->value_add);
+    const unsigned deltaShift   = __builtin_ctzll(deltaMask) - 2;
+    const uint32_t maxDelta     = (uint32_t)(deltaMask >> deltaShift);
+
+    pint_t* lastLoc = (pint_t*)&pageContent[lastLocationOffset+0];
+    pint_t lastValue = (pint_t)P::getP(*lastLoc);
+    if ( (lastValue - valueAdd) & deltaMask ) {
+        std::string dylibName;
+        std::string segName;
+        findDylibAndSegment((void*)pageContent, dylibName, segName);
+        _diagnostics.error("rebase pointer does not point within cache. lastOffset=0x%04X, seg=%s, dylib=%s\n",
+                            lastLocationOffset, segName.c_str(), dylibName.c_str());
+        return false;
+    }
+    if ( offset <= (lastLocationOffset+maxDelta) ) {
+        // previous location in range, make link from it
+        // encode this location into last value
+        pint_t delta = offset - lastLocationOffset;
+        pint_t newLastValue = ((lastValue - valueAdd) & valueMask) | (delta << deltaShift);
+        //warning("  add chain: delta = %d, lastOffset=0x%03X, offset=0x%03X, org value=0x%08lX, new value=0x%08lX",
+        //                    offset - lastLocationOffset, lastLocationOffset, offset, (long)lastValue, (long)newLastValue);
+        P::setP(*lastLoc, newLastValue);
         return true;
-    uint8_t* p = (uint8_t*)loc;
-    assert(p >= _regionStart);
-    assert(p < _regionEnd);
-
-    if ( _bitmap[(p-_regionStart)/kMinimumFixupAlignment] ) {
-#if BUILDING_APP_CACHE_UTIL
-        if ( level != nullptr ) {
-            uint8_t levelValue = _cacheLevels[(p-_regionStart)/kMinimumFixupAlignment];
-            if ( levelValue != (uint8_t)~0U )
-                *level = levelValue;
-        }
-#endif
-        return true;
-    }
-    return false;
-}
-
-void CacheBuilder::ASLR_Tracker::setHigh8(void* p, uint8_t high8)
-{
-    _high8Map[p] = high8;
-}
-
-void CacheBuilder::ASLR_Tracker::setAuthData(void* p, uint16_t diversity, bool hasAddrDiv, uint8_t key)
-{
-    _authDataMap[p] = {diversity, hasAddrDiv, key};
-}
-
-void CacheBuilder::ASLR_Tracker::setRebaseTarget32(void*p, uint32_t targetVMAddr)
-{
-    _rebaseTarget32[p] = targetVMAddr;
-}
-
-void CacheBuilder::ASLR_Tracker::setRebaseTarget64(void*p, uint64_t targetVMAddr)
-{
-    _rebaseTarget64[p] = targetVMAddr;
-}
-
-bool CacheBuilder::ASLR_Tracker::hasHigh8(void* p, uint8_t* highByte) const
-{
-    auto pos = _high8Map.find(p);
-    if ( pos == _high8Map.end() )
-        return false;
-    *highByte = pos->second;
+    }
+    //warning("  too big delta = %d, lastOffset=0x%03X, offset=0x%03X", offset - lastLocationOffset, lastLocationOffset, offset);
+
+    // distance between rebase locations is too far
+    // see if we can make a chain from non-rebase locations
+    uint16_t nonRebaseLocationOffsets[1024];
+    unsigned nrIndex = 0;
+    for (uint16_t i = lastLocationOffset; i < offset-maxDelta; ) {
+        nonRebaseLocationOffsets[nrIndex] = 0;
+        for (int j=maxDelta; j > 0; j -= 4) {
+            pint_t value = (pint_t)P::getP(*(pint_t*)&pageContent[i+j]);
+            if ( value == 0 ) {
+                // Steal values of 0 to be used in the rebase chain
+                nonRebaseLocationOffsets[nrIndex] = i+j;
+                break;
+            }
+        }
+        if ( nonRebaseLocationOffsets[nrIndex] == 0 ) {
+            lastValue = (pint_t)P::getP(*lastLoc);
+            pint_t newValue = ((lastValue - valueAdd) & valueMask);
+            //warning("   no way to make non-rebase delta chain, terminate off=0x%03X, old value=0x%08lX, new value=0x%08lX", lastLocationOffset, (long)value, (long)newValue);
+            P::setP(*lastLoc, newValue);
+            return false;
+        }
+        i = nonRebaseLocationOffsets[nrIndex];
+        ++nrIndex;
+    }
+
+    // we can make chain. go back and add each non-rebase location to chain
+    uint16_t prevOffset = lastLocationOffset;
+    pint_t* prevLoc = (pint_t*)&pageContent[prevOffset];
+    for (int n=0; n < nrIndex; ++n) {
+        uint16_t nOffset = nonRebaseLocationOffsets[n];
+        assert(nOffset != 0);
+        pint_t* nLoc = (pint_t*)&pageContent[nOffset];
+        uint32_t delta2 = nOffset - prevOffset;
+        pint_t value = (pint_t)P::getP(*prevLoc);
+        pint_t newValue;
+        if ( value == 0 )
+            newValue = (delta2 << deltaShift);
+        else
+            newValue = ((value - valueAdd) & valueMask) | (delta2 << deltaShift);
+        //warning("    non-rebase delta = %d, to off=0x%03X, old value=0x%08lX, new value=0x%08lX", delta2, nOffset, (long)value, (long)newValue);
+        P::setP(*prevLoc, newValue);
+        prevOffset = nOffset;
+        prevLoc = nLoc;
+    }
+    uint32_t delta3 = offset - prevOffset;
+    pint_t value = (pint_t)P::getP(*prevLoc);
+    pint_t newValue;
+    if ( value == 0 )
+        newValue = (delta3 << deltaShift);
+    else
+        newValue = ((value - valueAdd) & valueMask) | (delta3 << deltaShift);
+    //warning("    non-rebase delta = %d, to off=0x%03X, old value=0x%08lX, new value=0x%08lX", delta3, offset, (long)value, (long)newValue);
+    P::setP(*prevLoc, newValue);
+
     return true;
 }
 
-bool CacheBuilder::ASLR_Tracker::hasAuthData(void* p, uint16_t* diversity, bool* hasAddrDiv, uint8_t* key) const
-{
-    auto pos = _authDataMap.find(p);
-    if ( pos == _authDataMap.end() )
-        return false;
-    *diversity  = pos->second.diversity;
-    *hasAddrDiv = pos->second.addrDiv;
-    *key        = pos->second.key;
-    return true;
-}
-
-bool CacheBuilder::ASLR_Tracker::hasRebaseTarget32(void* p, uint32_t* vmAddr) const
-{
-    auto pos = _rebaseTarget32.find(p);
-    if ( pos == _rebaseTarget32.end() )
-        return false;
-    *vmAddr = pos->second;
-    return true;
-}
-
-bool CacheBuilder::ASLR_Tracker::hasRebaseTarget64(void* p, uint64_t* vmAddr) const
-{
-    auto pos = _rebaseTarget64.find(p);
-    if ( pos == _rebaseTarget64.end() )
-        return false;
-    *vmAddr = pos->second;
-    return true;
-}
-
-std::vector<void*> CacheBuilder::ASLR_Tracker::getRebaseTargets() const {
-    std::vector<void*> targets;
-    for (const auto& target : _rebaseTarget32)
-        targets.push_back(target.first);
-    for (const auto& target : _rebaseTarget64)
-        targets.push_back(target.first);
-    return targets;
-}
-
-////////////////////////////  DylibTextCoalescer ////////////////////////////////////
-
-bool CacheBuilder::DylibTextCoalescer::segmentWasCoalesced(std::string_view segmentName) const {
-    if (segmentName.size() > 16)
-        segmentName = segmentName.substr(0, 16);
-
-    if ( segmentName == "__OBJC_CONST" ) {
-        return !cfStrings.empty();
-    }
-
-    return false;
-}
-
-bool CacheBuilder::DylibTextCoalescer::sectionWasCoalesced(std::string_view segmentName,
-                                                           std::string_view sectionName) const {
-    if (segmentName.size() > 16)
-        segmentName = segmentName.substr(0, 16);
-    if (sectionName.size() > 16)
-        sectionName = sectionName.substr(0, 16);
-
-    if ( segmentName == "__TEXT" ) {
-        std::map<std::string_view, const DylibSectionOffsetToCacheSectionOffset*> supportedSections = {
-            { "__objc_classname", &objcClassNames },
-            { "__objc_methname", &objcMethNames },
-            { "__objc_methtype", &objcMethTypes }
-        };
-        auto it = supportedSections.find(sectionName);
-        if (it == supportedSections.end())
-            return false;
-        return !it->second->empty();
-    }
-
-    if ( segmentName == "__OBJC_CONST" ) {
-        if ( sectionName == "__cfstring" ) {
-            return !cfStrings.empty();
-        }
-    }
-
-    return false;
-}
-
-CacheBuilder::DylibTextCoalescer::DylibSectionOffsetToCacheSectionOffset&
-CacheBuilder::DylibTextCoalescer::getSectionCoalescer(std::string_view segmentName, std::string_view sectionName) {
-    if (segmentName.size() > 16)
-        segmentName = segmentName.substr(0, 16);
-    if (sectionName.size() > 16)
-        sectionName = sectionName.substr(0, 16);
-
-    if ( segmentName == "__TEXT" ) {
-        std::map<std::string_view, DylibSectionOffsetToCacheSectionOffset*> supportedSections = {
-            { "__objc_classname", &objcClassNames },
-            { "__objc_methname", &objcMethNames },
-            { "__objc_methtype", &objcMethTypes }
-        };
-        auto it = supportedSections.find(sectionName);
-        assert(it != supportedSections.end());
-        return *it->second;
-    }
-
-    if ( segmentName == "__OBJC_CONST" ) {
-        if ( sectionName == "__cfstring" ) {
-            return cfStrings;
-        }
-    }
-
-    assert(false);
-}
-
-const CacheBuilder::DylibTextCoalescer::DylibSectionOffsetToCacheSectionOffset&
-CacheBuilder::DylibTextCoalescer::getSectionCoalescer(std::string_view segmentName, std::string_view sectionName) const {
-    if (segmentName.size() > 16)
-        segmentName = segmentName.substr(0, 16);
-    if (sectionName.size() > 16)
-        sectionName = sectionName.substr(0, 16);
-
-    if ( segmentName == "__TEXT" ) {
-        std::map<std::string_view, const DylibSectionOffsetToCacheSectionOffset*> supportedSections = {
-            { "__objc_classname", &objcClassNames },
-            { "__objc_methname", &objcMethNames },
-            { "__objc_methtype", &objcMethTypes }
-        };
-        auto it = supportedSections.find(sectionName);
-        assert(it != supportedSections.end());
-        return *it->second;
-    }
-
-    if ( segmentName == "__OBJC_CONST" ) {
-        if ( sectionName == "__cfstring" ) {
-            return cfStrings;
-        }
-    }
-
-    assert(false);
-}
-
-////////////////////////////  CacheCoalescedText ////////////////////////////////////
-const char* CacheBuilder::CacheCoalescedText::SupportedSections[] = {
-    "__objc_classname",
-    "__objc_methname",
-    "__objc_methtype",
-};
-
-void CacheBuilder::CacheCoalescedText::
-     parseCoalescableText(const dyld3::MachOAnalyzer* ma,
-                          DylibTextCoalescer& textCoalescer,
-                          const IMPCaches::SelectorMap& selectors,
-                          IMPCaches::HoleMap& selectorsHoleMap) {
-    static const bool log = false;
-
-    // We can only remove sections if we know we have split seg v2 to point to it
-    // Otherwise, a PC relative load in the __TEXT segment wouldn't know how to point to the new strings
-    // which are no longer in the same segment
-    uint32_t splitSegSize = 0;
-    const void* splitSegStart = ma->getSplitSeg(splitSegSize);
-    if (!splitSegStart)
-        return;
-
-    if ((*(const uint8_t*)splitSegStart) != DYLD_CACHE_ADJ_V2_FORMAT)
-        return;
-
-    // We can only remove sections from the end of a segment, so cache them all and walk backwards.
-    __block std::vector<std::pair<std::string, dyld3::MachOAnalyzer::SectionInfo>> textSectionInfos;
-    ma->forEachSection(^(const dyld3::MachOAnalyzer::SectionInfo &sectInfo, bool malformedSectionRange, bool &stop) {
-        if (strcmp(sectInfo.segInfo.segName, "__TEXT") != 0)
-            return;
-        assert(!malformedSectionRange);
-        textSectionInfos.push_back({ sectInfo.sectName, sectInfo });
-    });
-
-    const std::set<std::string_view> supportedSections(std::begin(SupportedSections), std::end(SupportedSections));
-    int64_t slide = ma->getSlide();
-
-    bool isSelectorsSection = false;
-    for (auto sectionInfoIt = textSectionInfos.rbegin(); sectionInfoIt != textSectionInfos.rend(); ++sectionInfoIt) {
-        const std::string& sectionName = sectionInfoIt->first;
-        const dyld3::MachOAnalyzer::SectionInfo& sectInfo = sectionInfoIt->second;
-
-        isSelectorsSection = (sectionName == "__objc_methname");
-
-        // If we find a section we can't handle then stop here.  Hopefully we coalesced some from the end.
-        if (supportedSections.find(sectionName) == supportedSections.end())
-            break;
-
-        StringSection& cacheStringSection = getSectionData(sectionName);
-
-        DylibTextCoalescer::DylibSectionOffsetToCacheSectionOffset& sectionStringData = textCoalescer.getSectionCoalescer("__TEXT", sectionName);
-
-        // Walk the strings in this section
-        const uint8_t* content = (uint8_t*)(sectInfo.sectAddr + slide);
-        const char* s   = (char*)content;
-        const char* end = s + sectInfo.sectSize;
-        while ( s < end ) {
-            std::string_view str = s;
-            int cacheSectionOffset = 0;
-
-            auto it = cacheStringSection.stringsToOffsets.find(str);
-            if (it != cacheStringSection.stringsToOffsets.end()) {
-                // Debugging only.  If we didn't include the string then we saved that many bytes
-                cacheStringSection.savedSpace += str.size() + 1;
-                cacheSectionOffset = it->second;
-            } else if (isSelectorsSection) {
-                // If we are in the selectors section, we need to move
-                // the selectors in the selector map to their correct addresses,
-                // and fill the holes with the rest
-
-#if BUILDING_APP_CACHE_UTIL
-                cacheSectionOffset = cacheStringSection.bufferSize;
-#else
-                const IMPCaches::SelectorMap::UnderlyingMap & map = selectors.map;
-                IMPCaches::SelectorMap::UnderlyingMap::const_iterator selectorsIterator = map.find(str);
-                if (selectorsIterator != map.end()) {
-                    cacheSectionOffset = selectorsIterator->second->offset;
-                } else {
-                    cacheSectionOffset = selectorsHoleMap.addStringOfSize((unsigned)str.size() + 1);
-                }
-#endif
-                cacheStringSection.stringsToOffsets[str] = cacheSectionOffset;
-                uint32_t sizeAtLeast = cacheSectionOffset + (uint32_t)str.size() + 1;
-                if (cacheStringSection.bufferSize < sizeAtLeast) {
-                    cacheStringSection.bufferSize = sizeAtLeast;
-                }
-            } else {
-                auto itAndInserted = cacheStringSection.stringsToOffsets.insert({ str, cacheStringSection.bufferSize });
-                cacheSectionOffset = itAndInserted.first->second;
-                assert(itAndInserted.second);
-
-                cacheStringSection.bufferSize += str.size() + 1;
-                if (log) {
-                    printf("Selector: %s -> %s\n", ma->installName(), s);
-                }
-            }
-
-            // Now keep track of this offset in our source dylib as pointing to this offset
-            uint32_t sourceSectionOffset = (uint32_t)((uint64_t)s - (uint64_t)content);
-            sectionStringData[sourceSectionOffset] = cacheSectionOffset;
-            s += str.size() + 1;
-        }
-    }
-}
-
-void CacheBuilder::CacheCoalescedText::parseCFConstants(const dyld3::MachOAnalyzer *ma,
-                                                        DylibTextCoalescer &textCoalescer) {
-    static const bool log = false;
-
-    // FIXME: Re-enable this once we can correctly patch the shared cache
-    if ( ma != nullptr )
-        return;
-
-    if ( !ma->is64() )
-        return;
-
-    // We only support chained fixups as we need to rewrite binds/rebases after applying split seg
-    // and that is much easier with chained fixups than opcodes
-    if ( !ma->hasChainedFixupsLoadCommand() )
-        return;
-
-    // FIXME: Support DYLD_CHAINED_PTR_ARM64E_USERLAND once ld64 moves to it.
-    const uint16_t pointerFormat = ma->chainedPointerFormat();
-    if ( pointerFormat != DYLD_CHAINED_PTR_ARM64E )
-        return;
-
-    // We can only remove sections if we know we have split seg v2 to point to it
-    // Otherwise, a PC relative load in the __TEXT segment wouldn't know how to point to the new constants
-    // which are no longer in the same segment
-    if ( !ma->isSplitSegV2() )
-        return;
-
-    // We can only remove sections from the end of a segment, so cache them all and walk backwards.
-    __block std::vector<std::pair<std::string, dyld3::MachOAnalyzer::SectionInfo>> dataSectionInfos;
-    __block uint64_t cstringStartVMAddr = 0;
-    __block uint64_t cstringEndVMAddr = 0;
-    ma->forEachSection(^(const dyld3::MachOAnalyzer::SectionInfo &sectInfo, bool malformedSectionRange, bool &stop) {
-        if ( malformedSectionRange )
-            return;
-        if ( strcmp(sectInfo.segInfo.segName, "__OBJC_CONST") == 0 ) {
-            dataSectionInfos.push_back({ sectInfo.sectName, sectInfo });
-            return;
-        }
-        if ( strcmp(sectInfo.segInfo.segName, "__TEXT") == 0 ) {
-            if ( strcmp(sectInfo.sectName, "__cstring") == 0 ) {
-                if ( ( (sectInfo.sectFlags & SECTION_TYPE) == S_CSTRING_LITERALS ) ) {
-                    cstringStartVMAddr = sectInfo.sectAddr;
-                    cstringEndVMAddr = cstringStartVMAddr + sectInfo.sectSize;
-                }
-            }
-        }
-    });
-
-    // We need to clear the chained pointer fixups for the whole segment, so can only
-    // process any type of CF object if we can process them all
-    if ( dataSectionInfos.size() != 1 )
-        return;
-
-    if ( dataSectionInfos.front().first != "__cfstring" )
-        return;
-
-    if ( cstringStartVMAddr == 0 )
-        return;
-
-    const dyld3::MachOAnalyzer::SectionInfo& cfStringsSection = dataSectionInfos.back().second;
-
-    // A CFString is layed out in memory as
-    // {
-    //     uintptr_t   isa;
-    //     uint32_t    encoding;
-    //     uint32_t    padding;
-    //     uintptr_t   cstringData;
-    //     uintptr_t   cstringLength;
-    // }
-    const uint64_t cstringDataOffset = 16;
-    const char* className = cfStrings.isaClassName;
-    if ( cfStringsSection.sectSize % (uint32_t)DyldSharedCache::ConstantClasses::cfStringAtomSize ) {
-        // We don't support padding or any kind on the section
-        return;
-    }
-
-    uint64_t baseAddress = ma->preferredLoadAddress();
-
-    uint64_t startVMOffset = cfStringsSection.sectAddr - baseAddress;
-    uint64_t endVMOffset = startVMOffset + cfStringsSection.sectSize;
-
-    __block Diagnostics diag;
-
-    // Make sure no symbols are pointing in to this section
-    __block bool hasSymbols = false;
-    ma->forEachGlobalSymbol(diag, ^(const char *symbolName, uint64_t n_value, uint8_t n_type, uint8_t n_sect, uint16_t n_desc, bool &stop) {
-        uint64_t vmOffset = n_value - baseAddress;
-        if ( vmOffset < startVMOffset )
-            return;
-        if ( vmOffset >= endVMOffset )
-            return;
-        // In range of our section
-        hasSymbols = true;
-        stop = true;
-    });
-    if ( diag.hasError() )
-        return;
-    if ( hasSymbols )
-        return;
-
-    ma->forEachLocalSymbol(diag, ^(const char *symbolName, uint64_t n_value, uint8_t n_type, uint8_t n_sect, uint16_t n_desc, bool &stop) {
-        uint64_t vmOffset = n_value - baseAddress;
-        if ( vmOffset < startVMOffset )
-            return;
-        if ( vmOffset >= endVMOffset )
-            return;
-        // In range of our section
-        hasSymbols = true;
-        stop = true;
-    });
-    if ( diag.hasError() )
-        return;
-    if ( hasSymbols )
-        return;
-
-    ma->forEachExportedSymbol(diag, ^(const char *symbolName, uint64_t imageOffset, uint64_t flags, uint64_t other, const char *importName, bool &stop) {
-        if ( imageOffset < startVMOffset )
-            return;
-        if ( imageOffset >= endVMOffset )
-            return;
-        // In range of our section
-        hasSymbols = true;
-        stop = true;
-    });
-    if ( diag.hasError() )
-        return;
-    if ( hasSymbols )
-        return;
-
-    __block std::vector<const char*> dependentPaths;
-    ma->forEachDependentDylib(^(const char *loadPath, bool isWeak, bool isReExport,
-                                bool isUpward, uint32_t compatVersion, uint32_t curVersion, bool &stop) {
-        dependentPaths.push_back(loadPath);
-    });
-
-    // Find all the binds to the ISA class.  These delineate the atoms
-    // In CoreFoundation itself, we are looking for rebases to the ISA
-    __block std::vector<uint64_t> atomOffsets;
-
-    bool dylibExportsISA = strcmp(ma->installName(), cfStrings.isaInstallName) == 0;
-    if ( !dylibExportsISA ) {
-        // This dylib doens't export the class, so look for binds to the ISA
-        __block std::vector<std::pair<const char*, int>> bindTargetSymbols;
-        ma->forEachChainedFixupTarget(diag, ^(int libraryOrdinal, const char* symbolName, uint64_t addend, bool weakImport, bool& stop) {
-            bindTargetSymbols.push_back({ symbolName, libraryOrdinal });
-        });
-
-        __block bool foundBadBind = false;
-        ma->withChainStarts(diag, ma->chainStartsOffset(), ^(const dyld_chained_starts_in_image* startsInfo) {
-            if ( foundBadBind )
-                return;
-            ma->forEachFixupInAllChains(diag, startsInfo, false, ^(dyld3::MachOLoaded::ChainedFixupPointerOnDisk* fixupLoc,
-                                                                   const dyld_chained_starts_in_segment* segInfo, bool& stopFixups) {
-                // Skip anything not in this section
-                uint64_t vmOffset = (uint8_t*)fixupLoc - (uint8_t*)ma;
-                if ( vmOffset < startVMOffset )
-                    return;
-                if ( vmOffset >= endVMOffset )
-                    return;
-
-                uint32_t bindOrdinal;
-                int64_t  ptrAddend;
-                if ( fixupLoc->isBind(pointerFormat, bindOrdinal, ptrAddend) ) {
-                    if ( ptrAddend != 0 ) {
-                        foundBadBind = true;
-                        stopFixups = true;
+
+template <typename P>
+void CacheBuilder::addPageStarts(uint8_t* pageContent, const bool bitmap[], const dyld_cache_slide_info2* info,
+                                std::vector<uint16_t>& pageStarts, std::vector<uint16_t>& pageExtras)
+{
+    typedef typename P::uint_t     pint_t;
+
+    const pint_t   deltaMask    = (pint_t)(info->delta_mask);
+    const pint_t   valueMask    = ~deltaMask;
+    const uint32_t pageSize     = info->page_size;
+    const pint_t   valueAdd     = (pint_t)(info->value_add);
+
+    uint16_t startValue = DYLD_CACHE_SLIDE_PAGE_ATTR_NO_REBASE;
+    uint16_t lastLocationOffset = 0xFFFF;
+    for(int i=0; i < pageSize/4; ++i) {
+        unsigned offset = i*4;
+        if ( bitmap[i] ) {
+            if ( startValue == DYLD_CACHE_SLIDE_PAGE_ATTR_NO_REBASE ) {
+                // found first rebase location in page
+                startValue = i;
+            }
+            else if ( !makeRebaseChain<P>(pageContent, lastLocationOffset, offset, info) ) {
+                // can't record all rebasings in one chain
+                if ( (startValue & DYLD_CACHE_SLIDE_PAGE_ATTR_EXTRA) == 0 ) {
+                    // switch page_start to "extras" which is a list of chain starts
+                    unsigned indexInExtras = (unsigned)pageExtras.size();
+                    if ( indexInExtras > 0x3FFF ) {
+                        _diagnostics.error("rebase overflow in page extras");
                         return;
                     }
-                    if ( bindOrdinal >= bindTargetSymbols.size() ) {
-                        foundBadBind = true;
-                        stopFixups = true;
-                        return;
-                    }
-                    if ( strcmp(bindTargetSymbols[bindOrdinal].first, className) != 0 ) {
-                        foundBadBind = true;
-                        stopFixups = true;
-                        return;
-                    }
-                    int libOrdinal = bindTargetSymbols[bindOrdinal].second;
-                    if ( libOrdinal <= 0 ) {
-                        foundBadBind = true;
-                        stopFixups = true;
-                        return;
-                    }
-                    int depIndex = libOrdinal - 1;
-                    if ( depIndex >= dependentPaths.size() ) {
-                        foundBadBind = true;
-                        stopFixups = true;
-                        return;
-                    }
-                    const char* depLoadPath = dependentPaths[depIndex];
-                    // All dylibs must find the ISA in the same place
-                    if ( strcmp(cfStrings.isaInstallName, depLoadPath) != 0 ) {
-                        foundBadBind = true;
-                        stopFixups = true;
-                        return;
-                    }
-                    atomOffsets.push_back(vmOffset);
+                    pageExtras.push_back(startValue);
+                    startValue = indexInExtras | DYLD_CACHE_SLIDE_PAGE_ATTR_EXTRA;
                 }
-            });
+                pageExtras.push_back(i);
+            }
+            lastLocationOffset = offset;
+        }
+    }
+    if ( lastLocationOffset != 0xFFFF ) {
+        // mark end of chain
+        pint_t* lastLoc = (pint_t*)&pageContent[lastLocationOffset];
+        pint_t lastValue = (pint_t)P::getP(*lastLoc);
+        pint_t newValue = ((lastValue - valueAdd) & valueMask);
+        P::setP(*lastLoc, newValue);
+    }
+    if ( startValue & DYLD_CACHE_SLIDE_PAGE_ATTR_EXTRA ) {
+        // add end bit to extras
+        pageExtras.back() |= DYLD_CACHE_SLIDE_PAGE_ATTR_END;
+    }
+    pageStarts.push_back(startValue);
+}
+
+template <typename P>
+void CacheBuilder::writeSlideInfoV2()
+{
+    typedef typename P::uint_t    pint_t;
+    typedef typename P::E         E;
+    const uint32_t pageSize = 4096;
+
+    // build one 1024/4096 bool bitmap per page (4KB/16KB) of DATA
+    const dyld_cache_mapping_info* mappings = (dyld_cache_mapping_info*)((char*)_buffer + _buffer->header.mappingOffset);
+    uint8_t* const dataStart = (uint8_t*)_buffer + mappings[1].fileOffset;
+    uint8_t* const dataEnd   = dataStart + mappings[1].size;
+    unsigned pageCount = (unsigned)(mappings[1].size+pageSize-1)/pageSize;
+    const long bitmapSize = pageCount*(pageSize/4)*sizeof(bool);
+    bool* bitmap = (bool*)calloc(bitmapSize, 1);
+    for (void* p : _pointersForASLR) {
+        if ( (p < dataStart) || ( p > dataEnd) ) {
+            _diagnostics.error("DATA pointer for sliding, out of range\n");
+            free(bitmap);
+            return;
+        }
+        long byteOffset = (long)((uint8_t*)p - dataStart);
+        if ( (byteOffset % 4) != 0 ) {
+            _diagnostics.error("pointer not 4-byte aligned in DATA offset 0x%08lX\n", byteOffset);
+            free(bitmap);
+            return;
+        }
+        long boolIndex = byteOffset / 4;
+        // work around <rdar://24941083> by ignoring pointers to be slid that are NULL on disk
+        if ( *((pint_t*)p) == 0 ) {
+            std::string dylibName;
+            std::string segName;
+            findDylibAndSegment(p, dylibName, segName);
+            _diagnostics.warning("NULL pointer asked to be slid in %s at DATA region offset 0x%04lX of %s", segName.c_str(), byteOffset, dylibName.c_str());
+            continue;
+        }
+        bitmap[boolIndex] = true;
+    }
+
+    // fill in fixed info
+    assert(_slideInfoFileOffset != 0);
+    dyld_cache_slide_info2* info = (dyld_cache_slide_info2*)((uint8_t*)_buffer + _slideInfoFileOffset);
+    info->version    = 2;
+    info->page_size  = pageSize;
+    info->delta_mask = _archLayout->pointerDeltaMask;
+    info->value_add  = (sizeof(pint_t) == 8) ? 0 : _archLayout->sharedMemoryStart;  // only value_add for 32-bit archs
+
+    // set page starts and extras for each page
+    std::vector<uint16_t> pageStarts;
+    std::vector<uint16_t> pageExtras;
+    pageStarts.reserve(pageCount);
+    uint8_t* pageContent = dataStart;;
+    const bool* bitmapForPage = bitmap;
+    for (unsigned i=0; i < pageCount; ++i) {
+        //warning("page[%d]", i);
+        addPageStarts<P>(pageContent, bitmapForPage, info, pageStarts, pageExtras);
+        if ( _diagnostics.hasError() ) {
+            free(bitmap);
+            return;
+        }
+        pageContent += pageSize;
+        bitmapForPage += (sizeof(bool)*(pageSize/4));
+    }
+    free((void*)bitmap);
+
+    // fill in computed info
+    info->page_starts_offset = sizeof(dyld_cache_slide_info2);
+    info->page_starts_count  = (unsigned)pageStarts.size();
+    info->page_extras_offset = (unsigned)(sizeof(dyld_cache_slide_info2)+pageStarts.size()*sizeof(uint16_t));
+    info->page_extras_count  = (unsigned)pageExtras.size();
+    uint16_t* pageStartsBuffer = (uint16_t*)((char*)info + info->page_starts_offset);
+    uint16_t* pageExtrasBuffer = (uint16_t*)((char*)info + info->page_extras_offset);
+    for (unsigned i=0; i < pageStarts.size(); ++i)
+        pageStartsBuffer[i] = pageStarts[i];
+    for (unsigned i=0; i < pageExtras.size(); ++i)
+        pageExtrasBuffer[i] = pageExtras[i];
+    // update header with final size
+    _buffer->header.slideInfoSize = align(info->page_extras_offset + pageExtras.size()*sizeof(uint16_t), _archLayout->sharedRegionAlignP2);
+    if ( _buffer->header.slideInfoSize > _slideInfoBufferSizeAllocated ) {
+        _diagnostics.error("kernel slide info overflow buffer");
+    }
+    //warning("pageCount=%u, page_starts_count=%lu, page_extras_count=%lu", pageCount, pageStarts.size(), pageExtras.size());
+}
+
+
+/*
+void CacheBuilder::writeSlideInfoV1()
+{
+    // build one 128-byte bitmap per page (4096) of DATA
+    uint8_t* const dataStart = (uint8_t*)_buffer.get() + regions[1].fileOffset;
+    uint8_t* const dataEnd   = dataStart + regions[1].size;
+    const long bitmapSize = (dataEnd - dataStart)/(4*8);
+    uint8_t* bitmap = (uint8_t*)calloc(bitmapSize, 1);
+    for (void* p : _pointersForASLR) {
+        if ( (p < dataStart) || ( p > dataEnd) )
+            terminate("DATA pointer for sliding, out of range\n");
+        long offset = (long)((uint8_t*)p - dataStart);
+        if ( (offset % 4) != 0 )
+            terminate("pointer not 4-byte aligned in DATA offset 0x%08lX\n", offset);
+        long byteIndex = offset / (4*8);
+        long bitInByte =  (offset % 32) >> 2;
+        bitmap[byteIndex] |= (1 << bitInByte);
+    }
+
+    // allocate worst case size block of all slide info
+    const unsigned entry_size = 4096/(8*4); // 8 bits per byte, possible pointer every 4 bytes.
+    const unsigned toc_count = (unsigned)bitmapSize/entry_size;
+    dyld_cache_slide_info* slideInfo = (dyld_cache_slide_info*)((uint8_t*)_buffer + _slideInfoFileOffset);
+    slideInfo->version          = 1;
+    slideInfo->toc_offset       = sizeof(dyld_cache_slide_info);
+    slideInfo->toc_count        = toc_count;
+    slideInfo->entries_offset   = (slideInfo->toc_offset+2*toc_count+127)&(-128);
+    slideInfo->entries_count    = 0;
+    slideInfo->entries_size     = entry_size;
+    // append each unique entry
+    const dyldCacheSlideInfoEntry* bitmapAsEntries = (dyldCacheSlideInfoEntry*)bitmap;
+    dyldCacheSlideInfoEntry* const entriesInSlidInfo = (dyldCacheSlideInfoEntry*)((char*)slideInfo+slideInfo->entries_offset());
+    int entry_count = 0;
+    for (int i=0; i < toc_count; ++i) {
+        const dyldCacheSlideInfoEntry* thisEntry = &bitmapAsEntries[i];
+        // see if it is same as one already added
+        bool found = false;
+        for (int j=0; j < entry_count; ++j) {
+            if ( memcmp(thisEntry, &entriesInSlidInfo[j], entry_size) == 0 ) {
+                slideInfo->set_toc(i, j);
+                found = true;
+                break;
+            }
+        }
+        if ( !found ) {
+            // append to end
+            memcpy(&entriesInSlidInfo[entry_count], thisEntry, entry_size);
+            slideInfo->set_toc(i, entry_count++);
+        }
+    }
+    slideInfo->entries_count  = entry_count;
+    ::free((void*)bitmap);
+
+    _buffer.header->slideInfoSize = align(slideInfo->entries_offset + entry_count*entry_size, _archLayout->sharedRegionAlignP2);
+}
+
+*/
+
+void CacheBuilder::fipsSign() {
+    __block bool found = false;
+    _buffer->forEachImage(^(const mach_header* mh, const char* installName) {
+        __block void *hash_location = nullptr;
+        // Return if this is not corecrypto
+        if (strcmp(installName, "/usr/lib/system/libcorecrypto.dylib") != 0) {
+            return;
+        }
+        found = true;
+        auto parser = dyld3::MachOParser(mh, true);
+        parser.forEachLocalSymbol(_diagnostics, ^(const char *symbolName, uint64_t n_value, uint8_t n_type, uint8_t n_sect, uint16_t n_desc, bool &stop) {
+            if (strcmp(symbolName, "_fipspost_precalc_hmac") != 0)
+                return;
+            hash_location = (void *)(n_value - _archLayout->sharedMemoryStart + (uintptr_t)_buffer);
+            stop = true;
         });
-        if ( foundBadBind )
+
+        // Bail out if we did not find the symbol
+        if (hash_location == nullptr) {
+            _diagnostics.warning("Could not find _fipspost_precalc_hmac, skipping FIPS sealing");
             return;
-
-        if ( atomOffsets.empty() )
-            return;
-    }
-
-    if ( diag.hasError() )
-        return;
-
-    // Find all the rebases in the atoms, which correpond to pointers strings
-    __block std::map<uint64_t, uint64_t> sectionRebases;
-    ma->withChainStarts(diag, ma->chainStartsOffset(), ^(const dyld_chained_starts_in_image* startsInfo) {
-        ma->forEachFixupInAllChains(diag, startsInfo, false, ^(dyld3::MachOLoaded::ChainedFixupPointerOnDisk* fixupLoc, const dyld_chained_starts_in_segment* segInfo, bool& stopFixups) {
-            // Skip anything not in this section
-            uint64_t vmOffset = (uint8_t*)fixupLoc - (uint8_t*)ma;
-            if ( vmOffset < startVMOffset )
+        }
+
+        parser.forEachSection(^(const char *segName, const char *sectionName, uint32_t flags, const void *content, size_t size, bool illegalSectionSize, bool &stop) {
+            // FIXME: If we ever implement userspace __TEXT_EXEC this will need to be updated
+            if ( (strcmp(segName, "__TEXT" ) != 0) || (strcmp(sectionName, "__text") != 0) )  {
                 return;
-            if ( vmOffset >= endVMOffset )
+            }
+
+            if (illegalSectionSize) {
+                _diagnostics.error("FIPS section %s/%s extends beyond the end of the segment", segName, sectionName);
                 return;
-
-            uint64_t rebaseTargetRuntimeOffset;
-            if ( fixupLoc->isRebase(pointerFormat, 0, rebaseTargetRuntimeOffset) ) {
-                if ( dylibExportsISA && (rebaseTargetRuntimeOffset == cfStrings.isaVMOffset) ) {
-                    atomOffsets.push_back(vmOffset);
-                } else {
-                    sectionRebases[vmOffset] = rebaseTargetRuntimeOffset;
-                }
-            }
+            }
+
+            //We have _fipspost_precalc_hmac and __TEXT,__text, seal it
+            unsigned char hmac_key = 0;
+            CCHmac(kCCHmacAlgSHA256, &hmac_key, 1, content, size, hash_location);
+            stop = true;
         });
     });
-    if ( diag.hasError() )
+
+    if (!found) {
+        _diagnostics.warning("Could not find /usr/lib/system/libcorecrypto.dylib, skipping FIPS sealing");
+    }
+}
+
+void CacheBuilder::codeSign()
+{
+    uint8_t  dscHashType;
+    uint8_t  dscHashSize;
+    uint32_t dscDigestFormat;
+    bool agile = false;
+
+    // select which codesigning hash
+    switch (_options.codeSigningDigestMode) {
+        case DyldSharedCache::Agile:
+            agile = true;
+            // Fall through to SHA1, because the main code directory remains SHA1 for compatibility.
+        case DyldSharedCache::SHA1only:
+            dscHashType     = CS_HASHTYPE_SHA1;
+            dscHashSize     = CS_HASH_SIZE_SHA1;
+            dscDigestFormat = kCCDigestSHA1;
+            break;
+        case DyldSharedCache::SHA256only:
+            dscHashType     = CS_HASHTYPE_SHA256;
+            dscHashSize     = CS_HASH_SIZE_SHA256;
+            dscDigestFormat = kCCDigestSHA256;
+            break;
+        default:
+            _diagnostics.error("codeSigningDigestMode has unknown, unexpected value %d, bailing out.",
+                               _options.codeSigningDigestMode);
+            return;
+    }
+
+    std::string cacheIdentifier = "com.apple.dyld.cache." + _options.archName;
+    if ( _options.dylibsRemovedDuringMastering ) {
+        if ( _options.optimizeStubs  )
+            cacheIdentifier = "com.apple.dyld.cache." + _options.archName + ".release";
+        else
+            cacheIdentifier = "com.apple.dyld.cache." + _options.archName + ".development";
+    }
+    // get pointers into shared cache buffer
+    size_t          inBbufferSize = _currentFileSize;
+    const uint8_t*  inBuffer = (uint8_t*)_buffer;
+    uint8_t*        csBuffer = (uint8_t*)_buffer+inBbufferSize;
+
+    // layout code signature contents
+    uint32_t blobCount     = agile ? 4 : 3;
+    size_t   idSize        = cacheIdentifier.size()+1; // +1 for terminating 0
+    uint32_t slotCount     = (uint32_t)((inBbufferSize + CS_PAGE_SIZE - 1) / CS_PAGE_SIZE);
+    uint32_t xSlotCount    = CSSLOT_REQUIREMENTS;
+    size_t   idOffset      = offsetof(CS_CodeDirectory, end_withExecSeg);
+    size_t   hashOffset    = idOffset+idSize + dscHashSize*xSlotCount;
+    size_t   hash256Offset = idOffset+idSize + CS_HASH_SIZE_SHA256*xSlotCount;
+    size_t   cdSize        = hashOffset + (slotCount * dscHashSize);
+    size_t   cd256Size     = agile ? hash256Offset + (slotCount * CS_HASH_SIZE_SHA256) : 0;
+    size_t   reqsSize      = 12;
+    size_t   cmsSize       = sizeof(CS_Blob);
+    size_t   cdOffset      = sizeof(CS_SuperBlob) + blobCount*sizeof(CS_BlobIndex);
+    size_t   cd256Offset   = cdOffset + cdSize;
+    size_t   reqsOffset    = cd256Offset + cd256Size; // equals cdOffset + cdSize if not agile
+    size_t   cmsOffset     = reqsOffset + reqsSize;
+    size_t   sbSize        = cmsOffset + cmsSize;
+    size_t   sigSize       = align(sbSize, 14);       // keep whole cache 16KB aligned
+
+    if ( _currentFileSize+sigSize > _allocatedBufferSize ) {
+        _diagnostics.error("cache buffer too small to hold code signature (buffer size=%lldMB, signature size=%ldMB, free space=%lldMB)",
+                            _allocatedBufferSize/1024/1024, sigSize/1024/1024, (_allocatedBufferSize-_currentFileSize)/1024/1024);
         return;
-
-    // Every atom should have a single rebase to a cstring
-    if ( sectionRebases.size() != atomOffsets.size() )
+    }
+
+    // create overall code signature which is a superblob
+    CS_SuperBlob* sb = reinterpret_cast<CS_SuperBlob*>(csBuffer);
+    sb->magic           = htonl(CSMAGIC_EMBEDDED_SIGNATURE);
+    sb->length          = htonl(sbSize);
+    sb->count           = htonl(blobCount);
+    sb->index[0].type   = htonl(CSSLOT_CODEDIRECTORY);
+    sb->index[0].offset = htonl(cdOffset);
+    sb->index[1].type   = htonl(CSSLOT_REQUIREMENTS);
+    sb->index[1].offset = htonl(reqsOffset);
+    sb->index[2].type   = htonl(CSSLOT_CMS_SIGNATURE);
+    sb->index[2].offset = htonl(cmsOffset);
+    if ( agile ) {
+        sb->index[3].type = htonl(CSSLOT_ALTERNATE_CODEDIRECTORIES + 0);
+        sb->index[3].offset = htonl(cd256Offset);
+    }
+
+    // fill in empty requirements
+    CS_RequirementsBlob* reqs = (CS_RequirementsBlob*)(((char*)sb)+reqsOffset);
+    reqs->magic  = htonl(CSMAGIC_REQUIREMENTS);
+    reqs->length = htonl(sizeof(CS_RequirementsBlob));
+    reqs->data   = 0;
+
+    // initialize fixed fields of Code Directory
+    CS_CodeDirectory* cd = (CS_CodeDirectory*)(((char*)sb)+cdOffset);
+    cd->magic           = htonl(CSMAGIC_CODEDIRECTORY);
+    cd->length          = htonl(cdSize);
+    cd->version         = htonl(0x20400);               // supports exec segment
+    cd->flags           = htonl(kSecCodeSignatureAdhoc);
+    cd->hashOffset      = htonl(hashOffset);
+    cd->identOffset     = htonl(idOffset);
+    cd->nSpecialSlots   = htonl(xSlotCount);
+    cd->nCodeSlots      = htonl(slotCount);
+    cd->codeLimit       = htonl(inBbufferSize);
+    cd->hashSize        = dscHashSize;
+    cd->hashType        = dscHashType;
+    cd->platform        = 0;                            // not platform binary
+    cd->pageSize        = __builtin_ctz(CS_PAGE_SIZE);  // log2(CS_PAGE_SIZE);
+    cd->spare2          = 0;                            // unused (must be zero)
+    cd->scatterOffset   = 0;                            // not supported anymore
+    cd->teamOffset      = 0;                            // no team ID
+    cd->spare3          = 0;                            // unused (must be zero)
+    cd->codeLimit64     = 0;                            // falls back to codeLimit
+
+    // executable segment info
+    const dyld_cache_mapping_info* mappings = (dyld_cache_mapping_info*)((char*)_buffer + _buffer->header.mappingOffset);
+    cd->execSegBase     = htonll(mappings[0].fileOffset); // base of TEXT segment
+    cd->execSegLimit    = htonll(mappings[0].size);     // size of TEXT segment
+    cd->execSegFlags    = 0;                            // not a main binary
+
+    // initialize dynamic fields of Code Directory
+    strcpy((char*)cd + idOffset, cacheIdentifier.c_str());
+
+    // add special slot hashes
+    uint8_t* hashSlot = (uint8_t*)cd + hashOffset;
+    uint8_t* reqsHashSlot = &hashSlot[-CSSLOT_REQUIREMENTS*dscHashSize];
+    CCDigest(dscDigestFormat, (uint8_t*)reqs, sizeof(CS_RequirementsBlob), reqsHashSlot);
+
+    CS_CodeDirectory* cd256;
+    uint8_t* hash256Slot;
+    uint8_t* reqsHash256Slot;
+    if ( agile ) {
+        // Note that the assumption here is that the size up to the hashes is the same as for
+        // sha1 code directory, and that they come last, after everything else.
+
+        cd256 = (CS_CodeDirectory*)(((char*)sb)+cd256Offset);
+        cd256->magic           = htonl(CSMAGIC_CODEDIRECTORY);
+        cd256->length          = htonl(cd256Size);
+        cd256->version         = htonl(0x20400);               // supports exec segment
+        cd256->flags           = htonl(kSecCodeSignatureAdhoc);
+        cd256->hashOffset      = htonl(hash256Offset);
+        cd256->identOffset     = htonl(idOffset);
+        cd256->nSpecialSlots   = htonl(xSlotCount);
+        cd256->nCodeSlots      = htonl(slotCount);
+        cd256->codeLimit       = htonl(inBbufferSize);
+        cd256->hashSize        = CS_HASH_SIZE_SHA256;
+        cd256->hashType        = CS_HASHTYPE_SHA256;
+        cd256->platform        = 0;                            // not platform binary
+        cd256->pageSize        = __builtin_ctz(CS_PAGE_SIZE);  // log2(CS_PAGE_SIZE);
+        cd256->spare2          = 0;                            // unused (must be zero)
+        cd256->scatterOffset   = 0;                            // not supported anymore
+        cd256->teamOffset      = 0;                            // no team ID
+        cd256->spare3          = 0;                            // unused (must be zero)
+        cd256->codeLimit64     = 0;                            // falls back to codeLimit
+
+        // executable segment info
+        cd256->execSegBase     = cd->execSegBase;
+        cd256->execSegLimit    = cd->execSegLimit;
+        cd256->execSegFlags    = cd->execSegFlags;
+
+        // initialize dynamic fields of Code Directory
+        strcpy((char*)cd256 + idOffset, cacheIdentifier.c_str());
+
+        // add special slot hashes
+        hash256Slot = (uint8_t*)cd256 + hash256Offset;
+        reqsHash256Slot = &hash256Slot[-CSSLOT_REQUIREMENTS*CS_HASH_SIZE_SHA256];
+        CCDigest(kCCDigestSHA256, (uint8_t*)reqs, sizeof(CS_RequirementsBlob), reqsHash256Slot);
+    }
+    else {
+        cd256 = NULL;
+        hash256Slot = NULL;
+        reqsHash256Slot = NULL;
+    }
+
+    // fill in empty CMS blob for ad-hoc signing
+    CS_Blob* cms = (CS_Blob*)(((char*)sb)+cmsOffset);
+    cms->magic  = htonl(CSMAGIC_BLOBWRAPPER);
+    cms->length = htonl(sizeof(CS_Blob));
+
+    // alter header of cache to record size and location of code signature
+    // do this *before* hashing each page
+    _buffer->header.codeSignatureOffset = inBbufferSize;
+    _buffer->header.codeSignatureSize   = sigSize;
+
+    // compute hashes
+    const uint8_t* code = inBuffer;
+    for (uint32_t i=0; i < slotCount; ++i) {
+        CCDigest(dscDigestFormat, code, CS_PAGE_SIZE, hashSlot);
+        hashSlot += dscHashSize;
+
+        if ( agile ) {
+            CCDigest(kCCDigestSHA256, code, CS_PAGE_SIZE, hash256Slot);
+            hash256Slot += CS_HASH_SIZE_SHA256;
+        }
+        code += CS_PAGE_SIZE;
+    }
+
+    // hash of entire code directory (cdHash) uses same hash as each page
+    uint8_t fullCdHash[dscHashSize];
+    CCDigest(dscDigestFormat, (const uint8_t*)cd, cdSize, fullCdHash);
+    // Note: cdHash is defined as first 20 bytes of hash
+    memcpy(_cdHashFirst, fullCdHash, 20);
+    if ( agile ) {
+        uint8_t fullCdHash256[CS_HASH_SIZE_SHA256];
+        CCDigest(kCCDigestSHA256, (const uint8_t*)cd256, cd256Size, fullCdHash256);
+        // Note: cdHash is defined as first 20 bytes of hash, even for sha256
+        memcpy(_cdHashSecond, fullCdHash256, 20);
+    }
+    else {
+        memset(_cdHashSecond, 0, 20);
+    }
+
+    // increase file size to include newly append code signature
+    _currentFileSize += sigSize;
+}
+
+const bool CacheBuilder::agileSignature()
+{
+    return _options.codeSigningDigestMode == DyldSharedCache::Agile;
+}
+
+static const std::string cdHash(uint8_t hash[20])
+{
+    char buff[48];
+    for (int i = 0; i < 20; ++i)
+        sprintf(&buff[2*i], "%2.2x", hash[i]);
+    return buff;
+}
+
+const std::string CacheBuilder::cdHashFirst()
+{
+    return cdHash(_cdHashFirst);
+}
+
+const std::string CacheBuilder::cdHashSecond()
+{
+    return cdHash(_cdHashSecond);
+}
+
+void CacheBuilder::addCachedDylibsImageGroup(dyld3::ImageProxyGroup* dylibGroup)
+{
+    const dyld3::launch_cache::binary_format::ImageGroup* groupBinary = dylibGroup->makeImageGroupBinary(_diagnostics, _s_neverStubEliminate);
+    if (!groupBinary)
         return;
 
-    std::sort(atomOffsets.begin(), atomOffsets.end());
-    for (uint64_t atomOffset : atomOffsets) {
-        auto it = sectionRebases.find(atomOffset + cstringDataOffset);
-        if ( it == sectionRebases.end() )
-            return;
-    }
-
-    CFSection& stringSection = this->cfStrings;
-    DylibTextCoalescer::DylibSectionOffsetToCacheSectionOffset& sectionData = textCoalescer.getSectionCoalescer("__OBJC_CONST", "__cfstring");
-    for (uint64_t atomOffset : atomOffsets) {
-        if ( log )
-            printf("%s: found __cfstring at: 0x%llx\n", ma->installName(), atomOffset);
-
-        // Now keep track of this offset in our source dylib as pointing to this offset
-        uint32_t sourceSectionOffset = (uint32_t)(atomOffset - startVMOffset);
-        uint32_t cacheSectionOffset = stringSection.bufferSize;
-        sectionData[sourceSectionOffset] = cacheSectionOffset;
-        stringSection.bufferSize += (uint32_t)DyldSharedCache::ConstantClasses::cfStringAtomSize;
-    }
-}
-
-void CacheBuilder::CacheCoalescedText::clear() {
-    *this = CacheBuilder::CacheCoalescedText();
-}
-
-
-CacheBuilder::CacheCoalescedText::StringSection& CacheBuilder::CacheCoalescedText::getSectionData(std::string_view sectionName) {
-    if (sectionName.size() > 16)
-        sectionName = sectionName.substr(0, 16);
-    std::map<std::string_view, StringSection*> supportedSections = {
-        { "__objc_classname", &objcClassNames },
-        { "__objc_methname", &objcMethNames },
-        { "__objc_methtype", &objcMethTypes }
-    };
-    auto it = supportedSections.find(sectionName);
-    assert(it != supportedSections.end());
-    return *it->second;
-}
-
-
-const CacheBuilder::CacheCoalescedText::StringSection& CacheBuilder::CacheCoalescedText::getSectionData(std::string_view sectionName) const {
-    if (sectionName.size() > 16)
-        sectionName = sectionName.substr(0, 16);
-    std::map<std::string_view, const StringSection*> supportedSections = {
-        { "__objc_classname", &objcClassNames },
-        { "__objc_methname", &objcMethNames },
-        { "__objc_methtype", &objcMethTypes }
-    };
-    auto it = supportedSections.find(sectionName);
-    assert(it != supportedSections.end());
-    return *it->second;
-}
-
-uint64_t CacheBuilder::CacheCoalescedText::getSectionVMAddr(std::string_view segmentName,
-                                                            std::string_view sectionName) const {
-    if (segmentName.size() > 16)
-        segmentName = segmentName.substr(0, 16);
-    if (sectionName.size() > 16)
-        sectionName = sectionName.substr(0, 16);
-
-    if ( segmentName == "__TEXT" ) {
-        return getSectionData(sectionName).bufferVMAddr;
-    }
-
-    if ( segmentName == "__OBJC_CONST" ) {
-        if ( sectionName == "__cfstring" ) {
-            return cfStrings.bufferVMAddr;
-        }
-    }
-
-    assert(false);
-}
-
-uint8_t* CacheBuilder::CacheCoalescedText::getSectionBufferAddr(std::string_view segmentName,
-                                                                std::string_view sectionName) const {
-    if (segmentName.size() > 16)
-        segmentName = segmentName.substr(0, 16);
-    if (sectionName.size() > 16)
-        sectionName = sectionName.substr(0, 16);
-
-    if ( segmentName == "__TEXT" ) {
-        return getSectionData(sectionName).bufferAddr;
-    }
-
-    if ( segmentName == "__OBJC_CONST" ) {
-        if ( sectionName == "__cfstring" ) {
-            return cfStrings.bufferAddr;
-        }
-    }
-
-    assert(false);
-}
-
-uint64_t CacheBuilder::CacheCoalescedText::getSectionObjcTag(std::string_view segmentName,
-                                                             std::string_view sectionName) const {
-    if (segmentName.size() > 16)
-        segmentName = segmentName.substr(0, 16);
-    if (sectionName.size() > 16)
-        sectionName = sectionName.substr(0, 16);
-
-    if ( segmentName == "__TEXT" ) {
-        // Nothing has a tag in __TEXT
-        return 0;
-    }
-
-    if ( segmentName == "__OBJC_CONST" ) {
-        if ( sectionName == "__cfstring" ) {
-            // This is defined by objc as the tag we put in the high bits
-            // FIXME: Get a tag from objc
-            // return 1ULL << 63;
-            return 0;
-        }
-    }
-
-    assert(false);
-}
+    dyld3::launch_cache::ImageGroup group(groupBinary);
+    size_t groupSize = group.size();
+
+    if ( _currentFileSize+groupSize > _allocatedBufferSize ) {
+        _diagnostics.error("cache buffer too small to hold group[0] info (buffer size=%lldMB, group size=%ldMB, free space=%lldMB)",
+                            _allocatedBufferSize/1024/1024, groupSize/1024/1024, (_allocatedBufferSize-_currentFileSize)/1024/1024);
+        return;
+    }
+
+    // append ImageGroup data to read-only region of cache
+    uint8_t* loc = (uint8_t*)_buffer + _currentFileSize;
+    memcpy(loc, groupBinary, groupSize);
+    dyld_cache_mapping_info* mappings = (dyld_cache_mapping_info*)((char*)_buffer + _buffer->header.mappingOffset);
+    _buffer->header.dylibsImageGroupAddr = mappings[2].address + (_currentFileSize - mappings[2].fileOffset);
+    _buffer->header.dylibsImageGroupSize = (uint32_t)groupSize;
+    _currentFileSize += groupSize;
+    free((void*)groupBinary);
+}
+
+
+void CacheBuilder::addCachedOtherDylibsImageGroup(dyld3::ImageProxyGroup* otherGroup)
+{
+    const dyld3::launch_cache::binary_format::ImageGroup* groupBinary = otherGroup->makeImageGroupBinary(_diagnostics);
+    if (!groupBinary)
+        return;
+
+    dyld3::launch_cache::ImageGroup group(groupBinary);
+    size_t groupSize = group.size();
+
+    if ( _currentFileSize+groupSize > _allocatedBufferSize ) {
+        _diagnostics.error("cache buffer too small to hold group[1] info (buffer size=%lldMB, group size=%ldMB, free space=%lldMB)",
+                            _allocatedBufferSize/1024/1024, groupSize/1024/1024, (_allocatedBufferSize-_currentFileSize)/1024/1024);
+        return;
+    }
+
+    // append ImageGroup data to read-only region of cache
+    uint8_t* loc = (uint8_t*)_buffer + _currentFileSize;
+    memcpy(loc, groupBinary, groupSize);
+    dyld_cache_mapping_info* mappings = (dyld_cache_mapping_info*)((char*)_buffer + _buffer->header.mappingOffset);
+    _buffer->header.otherImageGroupAddr = mappings[2].address + (_currentFileSize - mappings[2].fileOffset);
+    _buffer->header.otherImageGroupSize = (uint32_t)groupSize;
+    _currentFileSize += groupSize;
+    free((void*)groupBinary);
+}
+
+void CacheBuilder::addClosures(const std::map<std::string, const dyld3::launch_cache::binary_format::Closure*>& closures)
+{
+    // preflight space needed
+    size_t closuresSpace = 0;
+    for (const auto& entry : closures) {
+        dyld3::launch_cache::Closure closure(entry.second);
+        closuresSpace += closure.size();
+    }
+    size_t freeSpace = _allocatedBufferSize - _currentFileSize;
+    if ( closuresSpace > freeSpace ) {
+        _diagnostics.error("cache buffer too small to hold all closures (buffer size=%lldMB, closures size=%ldMB, free space=%ldMB)",
+                            _allocatedBufferSize/1024/1024, closuresSpace/1024/1024, freeSpace/1024/1024);
+        return;
+    }
+
+    dyld_cache_mapping_info* mappings = (dyld_cache_mapping_info*)((char*)_buffer + _buffer->header.mappingOffset);
+    _buffer->header.progClosuresAddr = mappings[2].address + (_currentFileSize - mappings[2].fileOffset);
+    uint8_t* closuresBase = (uint8_t*)_buffer + _currentFileSize;
+    std::vector<DylibIndexTrie::Entry> closureEntrys;
+    uint32_t currentClosureOffset = 0;
+    for (const auto& entry : closures) {
+        const dyld3::launch_cache::binary_format::Closure* closBuf = entry.second;
+        closureEntrys.push_back(DylibIndexTrie::Entry(entry.first, DylibIndex(currentClosureOffset)));
+        dyld3::launch_cache::Closure closure(closBuf);
+        size_t size = closure.size();
+        assert((size % 4) == 0);
+        memcpy(closuresBase+currentClosureOffset, closBuf, size);
+        currentClosureOffset += size;
+        freeSpace -= size;
+        free((void*)closBuf);
+    }
+    _buffer->header.progClosuresSize = currentClosureOffset;
+    _currentFileSize += currentClosureOffset;
+    freeSpace = _allocatedBufferSize - _currentFileSize;
+
+    // build trie of indexes into closures list
+    DylibIndexTrie closureTrie(closureEntrys);
+    std::vector<uint8_t> trieBytes;
+    closureTrie.emit(trieBytes);
+    while ( (trieBytes.size() % 8) != 0 )
+        trieBytes.push_back(0);
+    if ( trieBytes.size() > freeSpace ) {
+        _diagnostics.error("cache buffer too small to hold all closures trie (buffer size=%lldMB, trie size=%ldMB, free space=%ldMB)",
+                            _allocatedBufferSize/1024/1024, trieBytes.size()/1024/1024, freeSpace/1024/1024);
+        return;
+    }
+    memcpy((uint8_t*)_buffer + _currentFileSize, &trieBytes[0], trieBytes.size());
+    _buffer->header.progClosuresTrieAddr = mappings[2].address + (_currentFileSize - mappings[2].fileOffset);
+    _buffer->header.progClosuresTrieSize = trieBytes.size();
+    _currentFileSize += trieBytes.size();
+}
+
+