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cache-builder/AppCacheBuilder.cpp dyld-1122.1 dyld-940
--- dyld/dyld-1122.1/cache-builder/AppCacheBuilder.cpp
+++ dyld/dyld-940/cache-builder/AppCacheBuilder.cpp
@@ -117,11 +117,9 @@
     }
 }
 
-void AppCacheBuilder::forEachDylibInfo(void (^callback)(const DylibInfo& dylib, Diagnostics& dylibDiag,
-                                                        cache_builder::ASLR_Tracker& dylibASLRTracker,
-                                                        const CacheBuilder::DylibSectionCoalescer* sectionCoalescer)) {
+void AppCacheBuilder::forEachDylibInfo(void (^callback)(const DylibInfo& dylib, Diagnostics& dylibDiag, ASLR_Tracker& dylibASLRTracker)) {
     for (const AppCacheDylibInfo& dylibInfo : sortedDylibs)
-        callback(dylibInfo, *dylibInfo.errors, _aslrTracker, &dylibInfo._coalescer);
+        callback(dylibInfo, *dylibInfo.errors, _aslrTracker);
 }
 
 const CacheBuilder::DylibInfo* AppCacheBuilder::getKernelStaticExecutableInputFile() const {
@@ -167,17 +165,9 @@
     if ( branchStubsRegion.bufferSize != 0 )
         callback(branchStubsRegion);
 
-    // textBootExecRegion
-    if ( textBootExecRegion.sizeInUse != 0 )
-        callback(textBootExecRegion);
-
     // dataConstRegion
     if ( dataConstRegion.sizeInUse != 0 )
         callback(dataConstRegion);
-
-    // dataSptmRegion
-    if ( dataSptmRegion.sizeInUse != 0 )
-        callback(dataSptmRegion);
 
     // branchGOTsRegion
     if ( branchGOTsRegion.bufferSize != 0 )
@@ -289,69 +279,6 @@
         totalTargets += seenSymbols.size();
     }
     return totalTargets;
-}
-
-bool AppCacheBuilder::hasSancovGateSection() const
-{
-    for ( const AppCacheDylibInfo& dylib : sortedDylibs ) {
-        const dyld3::MachOAnalyzer* ma = dylib.input->mappedFile.mh;
-        if ( ma->hasSection("__DATA", "__sancov_gate") )
-            return true;
-    }
-
-    return false;
-}
-
-bool AppCacheBuilder::removeStubs()
-{
-    // Only eliminate stubs in the base kernel collection.  We could eliminate stubs
-    // in the auxKC too, for those calls resolved within the auxKC, but its not worth it right now
-    if ( appCacheOptions.cacheKind != Options::AppCacheKind::kernel )
-        return false;
-
-    if ( _options.archs != &dyld3::GradedArchs::arm64e )
-        return false;
-
-    if ( hasSancovGateSection() )
-        return false;
-
-    return true;
-}
-
-void AppCacheBuilder::parseStubs()
-{
-    if ( !removeStubs() )
-        return;
-
-    for (AppCacheDylibInfo& dylib : sortedDylibs) {
-
-        const dyld3::MachOAnalyzer* ma = dylib.input->mappedFile.mh;
-
-        // We can only remove sections if we know we have split seg v2 to point to it
-        uint32_t splitSegSize = 0;
-        const void* splitSegStart = ma->getSplitSeg(splitSegSize);
-        if (!splitSegStart)
-            continue;
-
-        if ((*(const uint8_t*)splitSegStart) != DYLD_CACHE_ADJ_V2_FORMAT)
-            continue;
-
-        // Find __TEXT_EXEC __auth_stubs, and remove it if we have it
-        __block bool lastSectionWasAuthStubs = false;
-        ma->forEachSection(^(const dyld3::MachOAnalyzer::SectionInfo& sectInfo, bool malformedSectionRange, bool& stop) {
-            if ( strcmp(sectInfo.segInfo.segName, "__TEXT_EXEC") != 0 )
-                return;
-            lastSectionWasAuthStubs = false;
-            if ( strcmp(sectInfo.sectName, "__auth_stubs") == 0 ) {
-                // The auth stubs are only valid if the sections is 16-byte stubs
-                if ( ((sectInfo.sectFlags & SECTION_TYPE) == S_SYMBOL_STUBS) && (sectInfo.reserved2 == 16) )
-                    lastSectionWasAuthStubs = true;
-            }
-        });
-
-        if ( lastSectionWasAuthStubs )
-            dylib._coalescer.auth_stubs.sectionIsObliterated = true;
-    }
 }
 
 void AppCacheBuilder::assignSegmentRegionsAndOffsets()
@@ -466,7 +393,7 @@
     {
         // __TEXT segments with r/x permissions
         __block uint64_t offsetInRegion = 0;
-        for (AppCacheDylibInfo& dylib : sortedDylibs) {
+        for (DylibInfo& dylib : sortedDylibs) {
             bool canBePacked = dylib.input->mappedFile.mh->hasSplitSeg();
             if (!canBePacked)
                 continue;
@@ -477,34 +404,16 @@
                     textSegVmAddr = segInfo.vmAddr;
                 if ( strcmp(segInfo.segName, "__HIB") == 0 )
                     return;
-                if ( (strcmp(segInfo.segName, "__TEXT_BOOT_EXEC") == 0) && dylib.input->mappedFile.mh->isStaticExecutable() )
-                    return;
                 if ( segInfo.protections != (VM_PROT_READ | VM_PROT_EXECUTE) )
                    return;
-
-                // We may have coalesced the sections at the end of this segment.  In that case, shrink the segment to remove them.
-                __block size_t sizeOfSections = 0;
-                __block bool foundRemovedSection = false;
-                dylib.input->mappedFile.mh->forEachSection(^(const dyld3::MachOAnalyzer::SectionInfo &sectInfo, bool malformedSectionRange, bool &stopSection) {
-                    if (strcmp(sectInfo.segInfo.segName, segInfo.segName) != 0)
-                        return;
-                    if ( dylib._coalescer.sectionWasObliterated(segInfo.segName, sectInfo.sectName)) {
-                        foundRemovedSection = true;
-                    } else {
-                        sizeOfSections = sectInfo.sectAddr + sectInfo.sectSize - segInfo.vmAddr;
-                    }
-                });
-                if ( !foundRemovedSection )
-                    sizeOfSections = segInfo.sizeOfSections;
-
                 // kxld packs __TEXT_EXEC so we will do
                 // Note we align to at least 16-bytes as LDR's can scale up to 16 from their address
                 // and aligning them less than 16 would break that
                 uint32_t minAlignmentP2 = getMinAlignment(dylib.input->mappedFile.mh);
                 offsetInRegion = align(offsetInRegion, std::max(segInfo.p2align, 4U));
                 offsetInRegion = align(offsetInRegion, minAlignmentP2);
-                size_t copySize = std::min((size_t)segInfo.fileSize, (size_t)sizeOfSections);
-                uint64_t dstCacheSegmentSize = align(sizeOfSections, minAlignmentP2);
+                size_t copySize = std::min((size_t)segInfo.fileSize, (size_t)segInfo.sizeOfSections);
+                uint64_t dstCacheSegmentSize = align(segInfo.sizeOfSections, minAlignmentP2);
                 SegmentMappingInfo loc;
                 loc.srcSegment             = (uint8_t*)dylib.input->mappedFile.mh + segInfo.vmAddr - textSegVmAddr;
                 loc.segName                = segInfo.segName;
@@ -536,74 +445,6 @@
         branchStubsRegion.initProt      = VM_PROT_READ | VM_PROT_EXECUTE;
         branchStubsRegion.maxProt       = VM_PROT_READ | VM_PROT_EXECUTE;
         branchStubsRegion.name          = "__BRANCH_STUBS";
-    }
-
-    // __TEXT_BOOT_EXEC segments in xnu with r/x permissions
-    {
-        __block uint64_t offsetInRegion = 0;
-        for (AppCacheDylibInfo& dylib : sortedDylibs) {
-            bool canBePacked = dylib.input->mappedFile.mh->hasSplitSeg();
-            if (!canBePacked)
-                continue;
-
-            // Only do this for xnu
-            if ( !dylib.input->mappedFile.mh->isStaticExecutable() )
-                continue;
-
-            __block uint64_t textSegVmAddr = 0;
-            dylib.input->mappedFile.mh->forEachSegment(^(const dyld3::MachOFile::SegmentInfo& segInfo, bool& stop) {
-                if ( strcmp(segInfo.segName, "__TEXT") == 0 )
-                    textSegVmAddr = segInfo.vmAddr;
-                if ( strcmp(segInfo.segName, "__TEXT_BOOT_EXEC") != 0 )
-                    return;
-                if ( segInfo.protections != (VM_PROT_READ | VM_PROT_EXECUTE) )
-                    return;
-
-                // We may have coalesced the sections at the end of this segment.  In that case, shrink the segment to remove them.
-                __block size_t sizeOfSections = 0;
-                __block bool foundRemovedSection = false;
-                dylib.input->mappedFile.mh->forEachSection(^(const dyld3::MachOAnalyzer::SectionInfo &sectInfo, bool malformedSectionRange, bool &stopSection) {
-                    if (strcmp(sectInfo.segInfo.segName, segInfo.segName) != 0)
-                        return;
-                    if ( dylib._coalescer.sectionWasObliterated(segInfo.segName, sectInfo.sectName)) {
-                        foundRemovedSection = true;
-                    } else {
-                        sizeOfSections = sectInfo.sectAddr + sectInfo.sectSize - segInfo.vmAddr;
-                    }
-                });
-                if ( !foundRemovedSection )
-                    sizeOfSections = segInfo.sizeOfSections;
-
-                // kxld packs __TEXT_EXEC so we will do
-                // Note we align to at least 16-bytes as LDR's can scale up to 16 from their address
-                // and aligning them less than 16 would break that
-                uint32_t minAlignmentP2 = getMinAlignment(dylib.input->mappedFile.mh);
-                offsetInRegion = align(offsetInRegion, std::max(segInfo.p2align, 4U));
-                offsetInRegion = align(offsetInRegion, minAlignmentP2);
-                size_t copySize = std::min((size_t)segInfo.fileSize, (size_t)sizeOfSections);
-                uint64_t dstCacheSegmentSize = align(sizeOfSections, minAlignmentP2);
-                SegmentMappingInfo loc;
-                loc.srcSegment             = (uint8_t*)dylib.input->mappedFile.mh + segInfo.vmAddr - textSegVmAddr;
-                loc.segName                = segInfo.segName;
-                loc.dstSegment             = nullptr;
-                loc.dstCacheUnslidAddress  = offsetInRegion; // This will be updated later once we've assigned addresses
-                loc.dstCacheFileOffset     = (uint32_t)offsetInRegion;
-                loc.dstCacheSegmentSize    = (uint32_t)dstCacheSegmentSize;
-                loc.dstCacheFileSize       = (uint32_t)copySize;
-                loc.copySegmentSize        = (uint32_t)copySize;
-                loc.srcSegmentIndex        = segInfo.segIndex;
-                loc.parentRegion           = &textBootExecRegion;
-                dylib.cacheLocation[segInfo.segIndex] = loc;
-                offsetInRegion += loc.dstCacheSegmentSize;
-            });
-        }
-
-        // align r/x region end
-        textBootExecRegion.bufferSize  = align(offsetInRegion, 14);
-        textBootExecRegion.sizeInUse   = textBootExecRegion.bufferSize;
-        textBootExecRegion.initProt    = VM_PROT_READ | VM_PROT_EXECUTE;
-        textBootExecRegion.maxProt     = VM_PROT_READ | VM_PROT_EXECUTE;
-        textBootExecRegion.name        = "__TEXT_BOOT_EXEC";
     }
 
     // __DATA_CONST segments
@@ -652,51 +493,6 @@
         dataConstRegion.maxProt     = VM_PROT_READ;
         dataConstRegion.name        = "__DATA_CONST";
     }
-
-    // __DATA_SPTM segments
-    {
-        __block uint64_t offsetInRegion = 0;
-        for (DylibInfo& dylib : sortedDylibs) {
-            if (!dylib.input->mappedFile.mh->hasSplitSeg())
-                continue;
-
-            __block uint64_t textSegVmAddr = 0;
-            dylib.input->mappedFile.mh->forEachSegment(^(const dyld3::MachOFile::SegmentInfo& segInfo, bool& stop) {
-                if ( strcmp(segInfo.segName, "__TEXT") == 0 )
-                    textSegVmAddr = segInfo.vmAddr;
-                if ( (segInfo.protections & VM_PROT_EXECUTE) != 0 )
-                    return;
-                if ( (strcmp(segInfo.segName, "__DATA_SPTM") != 0) )
-                    return;
-                uint32_t minAlignmentP2 = getMinAlignment(dylib.input->mappedFile.mh);
-                offsetInRegion = align(offsetInRegion, segInfo.p2align);
-                offsetInRegion = align(offsetInRegion, minAlignmentP2);
-                size_t copySize = std::min((size_t)segInfo.fileSize, (size_t)segInfo.sizeOfSections);
-                uint64_t dstCacheSegmentSize = align(segInfo.sizeOfSections, minAlignmentP2);
-                SegmentMappingInfo loc;
-                loc.srcSegment             = (uint8_t*)dylib.input->mappedFile.mh + segInfo.vmAddr - textSegVmAddr;
-                loc.segName                = segInfo.segName;
-                loc.dstSegment             = nullptr;
-                loc.dstCacheUnslidAddress  = offsetInRegion; // This will be updated later once we've assigned addresses
-                loc.dstCacheFileOffset     = (uint32_t)offsetInRegion;
-                loc.dstCacheSegmentSize    = (uint32_t)dstCacheSegmentSize;
-                loc.dstCacheFileSize       = (uint32_t)copySize;
-                loc.copySegmentSize        = (uint32_t)copySize;
-                loc.srcSegmentIndex        = segInfo.segIndex;
-                loc.parentRegion           = &dataSptmRegion;
-                dylib.cacheLocation[segInfo.segIndex] = loc;
-                offsetInRegion += loc.dstCacheSegmentSize;
-            });
-        }
-
-        // align r/o region end
-        dataSptmRegion.bufferSize  = align(offsetInRegion, 14);
-        dataSptmRegion.sizeInUse   = dataSptmRegion.bufferSize;
-        dataSptmRegion.initProt    = VM_PROT_READ;
-        dataSptmRegion.maxProt     = VM_PROT_READ;
-        dataSptmRegion.name        = "__DATA_SPTM";
-    }
-
 
     // Branch GOTs
     if ( branchTargetsFromKexts != 0 ) {
@@ -765,7 +561,6 @@
                 continue;
 
             __block uint64_t textSegVmAddr = 0;
-            __block uint64_t hibernateAddress = 0;
             dylib.input->mappedFile.mh->forEachSegment(^(const dyld3::MachOFile::SegmentInfo& segInfo, bool& stop) {
                 if ( strcmp(segInfo.segName, "__TEXT") == 0 )
                     textSegVmAddr = segInfo.vmAddr;
@@ -789,21 +584,6 @@
                 hibernateAddress = segInfo.vmAddr;
             });
 
-            if ( offsetInRegion != 0 ) {
-                // Pad out the VM offset so that the cache header starts where the base address
-                // really should be
-                uint64_t paddedSize = cacheBaseAddress - hibernateAddress;
-                if ( offsetInRegion > paddedSize ) {
-                    _diagnostics.error("Could not lay out __HIB segment");
-                    return;
-                }
-                offsetInRegion = paddedSize;
-
-                // Set the base address to the hibernate address so that we actually put the
-                // hibernate segment there
-                cacheBaseAddress = hibernateAddress;
-            }
-
             // Only xnu has __HIB, so no need to continue once we've found it.
             break;
         }
@@ -936,16 +716,16 @@
             }
 
             // _PrelinkExecutableSize
-            // Use the size of the TEXT sections in the cache.  This is required as we pack segments
-            __block uint64_t textSegSize = 0;
+            // This seems to be the file size of __TEXT
+            __block uint64_t textSegFileSize = 0;
             if ( info.ma != nullptr ) {
                 info.ma->forEachSegment(^(const dyld3::MachOFile::SegmentInfo& segInfo, bool& stop) {
                     if ( strcmp(segInfo.segName, "__TEXT") == 0 )
-                        textSegSize = segInfo.sizeOfSections == 0 ? segInfo.fileSize : segInfo.sizeOfSections;
+                        textSegFileSize = segInfo.fileSize;
                 });
             }
-            if (textSegSize != 0) {
-                CFNumberRef fileSizeRef = CFNumberCreate(kCFAllocatorDefault, kCFNumberLongLongType, &textSegSize);
+            if (textSegFileSize != 0) {
+                CFNumberRef fileSizeRef = CFNumberCreate(kCFAllocatorDefault, kCFNumberLongLongType, &textSegFileSize);
                 CFDictionarySetValue(dictCopyRef, CFSTR("_PrelinkExecutableSize"), fileSizeRef);
                 CFRelease(fileSizeRef);
             }
@@ -1108,23 +888,15 @@
                 return;
             // Keep segments 4K or more aligned
             offsetInRegion = align(offsetInRegion, std::max((int)segInfo.p2align, (int)12));
-            size_t copySize = segInfo.fileSize;
-
-            // HACK: When we adjust LINKEDIT, we may grow function starts.  This is because the kernel and kexts
-            // have __TEXT_EXEC __text (or other __text) which is going to be moved away from __TEXT.
-            // That is, the first function start is effectively going to be an offset from __TEXT to __TEXT_EXEC
-            // and that may grow.
-            // Everything is ULEB encoded. We've only seen a need for 8-bytes more, but use 16-bytes to be safe
-            const uint32_t extraLinkeditSpace = 16;
-
+            size_t copySize = std::min((size_t)segInfo.fileSize, (size_t)segInfo.sizeOfSections);
             SegmentMappingInfo loc;
             loc.srcSegment             = (uint8_t*)dylib.input->mappedFile.mh + segInfo.vmAddr - textSegVmAddr;
             loc.segName                = segInfo.segName;
             loc.dstSegment             = nullptr;
             loc.dstCacheUnslidAddress  = offsetInRegion; // This will be updated later once we've assigned addresses
             loc.dstCacheFileOffset     = (uint32_t)offsetInRegion;
-            loc.dstCacheSegmentSize    = (uint32_t)align(copySize + extraLinkeditSpace, 12);
-            loc.dstCacheFileSize       = (uint32_t)copySize + extraLinkeditSpace;
+            loc.dstCacheSegmentSize    = (uint32_t)align(segInfo.sizeOfSections, 12);
+            loc.dstCacheFileSize       = (uint32_t)copySize;
             loc.copySegmentSize        = (uint32_t)copySize;
             loc.srcSegmentIndex        = segInfo.segIndex;
             loc.parentRegion           = &_readOnlyRegion;
@@ -1168,8 +940,6 @@
         uint64_t numBytesForPageStarts = 0;
         if ( dataConstRegion.sizeInUse != 0 )
             numBytesForPageStarts += sizeof(dyld_chained_starts_in_segment) + (sizeof(uint16_t) * numWritablePagesToFixup(dataConstRegion.bufferSize));
-        if ( dataSptmRegion.sizeInUse != 0 )
-            numBytesForPageStarts += sizeof(dyld_chained_starts_in_segment) + (sizeof(uint16_t) * numWritablePagesToFixup(dataSptmRegion.bufferSize));
         if ( branchGOTsRegion.bufferSize != 0 )
             numBytesForPageStarts += sizeof(dyld_chained_starts_in_segment) + (sizeof(uint16_t) * numWritablePagesToFixup(branchGOTsRegion.bufferSize));
         if ( readWriteRegion.sizeInUse != 0 )
@@ -1337,17 +1107,16 @@
                                    std::map<std::string, DylibSymbols>& dylibsToSymbols);
     void findVTables(uint8_t currentLevel, const dyld3::MachOAnalyzer* kernelMA,
                      std::map<std::string, DylibSymbols>& dylibsToSymbols,
-                     const cache_builder::ASLR_Tracker& aslrTracker,
+                     const AppCacheBuilder::ASLR_Tracker& aslrTracker,
                      const std::map<const uint8_t*, const VTableBindSymbol>& missingBindLocations);
     void calculateSymbols();
     void patchVTables(Diagnostics& diags,
                       std::map<const uint8_t*, const VTableBindSymbol>& missingBindLocations,
-                      cache_builder::ASLR_Tracker& aslrTracker,
+                      AppCacheBuilder::ASLR_Tracker& aslrTracker,
                       uint8_t currentLevel);
 
 private:
 
-    __attribute__((format(printf, 2, 3)))
     void logFunc(const char* format, ...) {
         if ( logPatching ) {
             va_list list;
@@ -1357,7 +1126,6 @@
         }
     };
 
-    __attribute__((format(printf, 2, 3)))
     void logFuncVerbose(const char* format, ...) {
         if ( logPatchingVerbose ) {
             va_list list;
@@ -2076,7 +1844,7 @@
 
 void VTablePatcher::findVTables(uint8_t currentLevel, const dyld3::MachOAnalyzer* kernelMA,
                                 std::map<std::string, DylibSymbols>& dylibsToSymbols,
-                                const cache_builder::ASLR_Tracker& aslrTracker,
+                                const AppCacheBuilder::ASLR_Tracker& aslrTracker,
                                 const std::map<const uint8_t*, const VTableBindSymbol>& missingBindLocations)
 {
     const bool is64 = pointerSize == 8;
@@ -2346,7 +2114,7 @@
 
 void VTablePatcher::patchVTables(Diagnostics& diags,
                                  std::map<const uint8_t*, const VTableBindSymbol>& missingBindLocations,
-                                 cache_builder::ASLR_Tracker& aslrTracker,
+                                 AppCacheBuilder::ASLR_Tracker& aslrTracker,
                                  uint8_t currentLevel)
 {
     const bool is64 = pointerSize == 8;
@@ -2418,7 +2186,7 @@
             }
         }
 
-        logFunc("Found %lu vtable items: '%s'\n", vtable.entries.size(), vtable.name.c_str());
+        logFunc("Found %d vtable items: '%s'\n", vtable.entries.size(), vtable.name.c_str());
     };
 
     // Map from MachO to diagnostics to emit for that file
@@ -2621,7 +2389,7 @@
 struct DylibFixups {
     void processFixups(const std::map<std::string, DylibSymbols>& dylibsToSymbols,
                        const std::unordered_map<std::string_view, std::vector<DylibSymbolLocation>>& symbolMap,
-                       const std::string& kernelID, const cache_builder::ASLR_Tracker& aslrTracker);
+                       const std::string& kernelID, const CacheBuilder::ASLR_Tracker& aslrTracker);
 
     // Inputs
     const dyld3::MachOAnalyzer*     ma              = nullptr;
@@ -2649,7 +2417,7 @@
 
 void DylibFixups::processFixups(const std::map<std::string, DylibSymbols>& dylibsToSymbols,
                                 const std::unordered_map<std::string_view, std::vector<DylibSymbolLocation>>& symbolMap,
-                                const std::string& kernelID, const cache_builder::ASLR_Tracker& aslrTracker) {
+                                const std::string& kernelID, const CacheBuilder::ASLR_Tracker& aslrTracker) {
     auto& resolvedBindLocations = dylibSymbols.resolvedBindLocations;
     const std::string& dylibID = dylibSymbols.dylibName;
 
@@ -3190,152 +2958,13 @@
     return std::make_unique<std::unordered_set<std::string>>(std::move(symbols));
 }
 
-void AppCacheBuilder::patchVTables(const dyld3::MachOAnalyzer* kernelMA,
-                                   const std::string& kernelID,
-                                   std::map<std::string, DylibSymbols>& dylibsToSymbols,
-                                   std::map<const uint8_t*, const VTableBindSymbol>& missingBindLocations)
-{
-    // We only patch vtables on macOS.  Luckily the platform is in the kernel binary
-    if ( !kernelMA->builtForPlatform(dyld3::Platform::macOS) )
-        return;
-
-    auto vtablePatcherOwner = std::make_unique<VTablePatcher>(numFixupLevels);
-    VTablePatcher& vtablePatcher = *vtablePatcherOwner.get();
-
-    uint8_t currentLevel = getCurrentFixupLevel();
-
-    // Add all the collections to the vtable patcher
-    if ( existingKernelCollection != nullptr ) {
-        // The baseKC for x86_64 has __HIB mapped first , so we need to get either the __DATA or __TEXT depending on what is earliest
-        // The kernel base address is still __TEXT, even if __DATA or __HIB is mapped prior to that.
-        // The loader may have loaded something before __TEXT, but the existingKernelCollection pointer still corresponds to __TEXT
-        __block uint64_t baseAddress = ~0ULL;
-        existingKernelCollection->forEachSegment(^(const dyld3::MachOAnalyzer::SegmentInfo& info, bool& stop) {
-            baseAddress = std::min(baseAddress, info.vmAddr);
-        });
-
-        // The existing collection is a pointer to the mach_header for the baseKC, but __HIB and other segments may be before that
-        // Offset those here
-        uint64_t basePointerOffset = existingKernelCollection->preferredLoadAddress() - baseAddress;
-        const uint8_t* basePointer = (uint8_t*)existingKernelCollection - basePointerOffset;
-
-        vtablePatcher.addKernelCollection(existingKernelCollection, Options::AppCacheKind::kernel,
-                                          basePointer, baseAddress);
-    }
-
-    if ( pageableKernelCollection != nullptr ) {
-        // The baseKC for x86_64 has __HIB mapped first , so we need to get either the __DATA or __TEXT depending on what is earliest
-        // The kernel base address is still __TEXT, even if __DATA or __HIB is mapped prior to that.
-        // The loader may have loaded something before __TEXT, but the existingKernelCollection pointer still corresponds to __TEXT
-        __block uint64_t baseAddress = ~0ULL;
-        pageableKernelCollection->forEachSegment(^(const dyld3::MachOAnalyzer::SegmentInfo& info, bool& stop) {
-            baseAddress = std::min(baseAddress, info.vmAddr);
-        });
-
-        // The existing collection is a pointer to the mach_header for the baseKC, but __HIB and other segments may be before that
-        // Offset those here
-        uint64_t basePointerOffset = pageableKernelCollection->preferredLoadAddress() - baseAddress;
-        const uint8_t* basePointer = (uint8_t*)pageableKernelCollection - basePointerOffset;
-
-        vtablePatcher.addKernelCollection(pageableKernelCollection, Options::AppCacheKind::pageableKC,
-                                          basePointer, baseAddress);
-    }
-
-    // Also add our KC
-    vtablePatcher.addKernelCollection((const dyld3::MachOAppCache*)cacheHeader.header, appCacheOptions.cacheKind,
-                                      (const uint8_t*)_fullAllocatedBuffer, cacheBaseAddress);
-
-    // Add all the dylibs to the patcher
-    {
-        if ( existingKernelCollection != nullptr ) {
-            uint8_t fixupLevel = getFixupLevel(Options::AppCacheKind::kernel);
-
-            __block std::map<std::string, std::vector<std::string>> kextDependencies;
-            kextDependencies[kernelID] = {};
-            existingKernelCollection->forEachPrelinkInfoLibrary(_diagnostics,
-                                                                ^(const char *bundleName, const char* relativePath,
-                                                                  const std::vector<const char *> &deps) {
-                std::vector<std::string>& dependencies = kextDependencies[bundleName];
-                dependencies.insert(dependencies.end(), deps.begin(), deps.end());
-            });
-
-            existingKernelCollection->forEachDylib(_diagnostics, ^(const dyld3::MachOAnalyzer *ma, const char *dylibID, bool &stop) {
-                auto depsIt = kextDependencies.find(dylibID);
-                assert(depsIt != kextDependencies.end());
-                vtablePatcher.addDylib(_diagnostics, ma, dylibID, depsIt->second, fixupLevel);
-            });
-        }
-
-        if ( pageableKernelCollection != nullptr ) {
-            uint8_t fixupLevel = getFixupLevel(Options::AppCacheKind::pageableKC);
-
-            __block std::map<std::string, std::vector<std::string>> kextDependencies;
-            pageableKernelCollection->forEachPrelinkInfoLibrary(_diagnostics,
-                                                                ^(const char *bundleName, const char* relativePath,
-                                                                  const std::vector<const char *> &deps) {
-                std::vector<std::string>& dependencies = kextDependencies[bundleName];
-                dependencies.insert(dependencies.end(), deps.begin(), deps.end());
-            });
-
-            pageableKernelCollection->forEachDylib(_diagnostics, ^(const dyld3::MachOAnalyzer *ma, const char *dylibID, bool &stop) {
-                auto depsIt = kextDependencies.find(dylibID);
-                assert(depsIt != kextDependencies.end());
-                vtablePatcher.addDylib(_diagnostics, ma, dylibID, depsIt->second, fixupLevel);
-            });
-        }
-
-        forEachCacheDylib(^(const dyld3::MachOAnalyzer *ma, const std::string &dylibID, DylibStripMode stripMode,
-                            const std::vector<std::string> &dependencies, Diagnostics& dylibDiag, bool &stop) {
-            vtablePatcher.addDylib(dylibDiag, ma, dylibID, dependencies, currentLevel);
-        });
-    }
-
-    vtablePatcher.findMetaclassDefinitions(dylibsToSymbols, kernelID, kernelMA, appCacheOptions.cacheKind);
-    vtablePatcher.findExistingFixups(_diagnostics, existingKernelCollection, pageableKernelCollection);
-    if ( _diagnostics.hasError() )
-        return;
-
-    // Add vtables from the base KC if we have one
-    if ( existingKernelCollection != nullptr ) {
-        vtablePatcher.findBaseKernelVTables(_diagnostics, existingKernelCollection, dylibsToSymbols);
-        if ( _diagnostics.hasError() )
-            return;
-    }
-
-    // Add vtables from the pageable KC if we have one
-    if ( pageableKernelCollection != nullptr ) {
-        vtablePatcher.findPageableKernelVTables(_diagnostics, pageableKernelCollection, dylibsToSymbols);
-        if ( _diagnostics.hasError() )
-            return;
-    }
-
-    // Add vables from our level
-    vtablePatcher.findVTables(currentLevel, kernelMA, dylibsToSymbols, _aslrTracker, missingBindLocations);
-
-    // Don't run the patcher if we have a failure finding the vtables
-    if ( vtablePatcher.hasError() ) {
-        _diagnostics.error("One or more binaries has an error which prevented linking.  See other errors.");
-        return;
-    }
-
-    // Now patch all of the vtables.
-    vtablePatcher.patchVTables(_diagnostics, missingBindLocations, _aslrTracker, currentLevel);
-    if ( _diagnostics.hasError() )
-        return;
-
-    if ( vtablePatcher.hasError() ) {
-        _diagnostics.error("One or more binaries has an error which prevented linking.  See other errors.");
-        return;
-    }
-
-    // FIXME: We could move vtablePatcherOwner to a worker thread to be destroyed
-    vtablePatcherOwner.reset();
-}
-
 void AppCacheBuilder::processFixups()
 {
     auto dylibsToSymbolsOwner = std::make_unique<std::map<std::string, DylibSymbols>>();
     std::map<std::string, DylibSymbols>& dylibsToSymbols = *dylibsToSymbolsOwner.get();
+
+    auto vtablePatcherOwner = std::make_unique<VTablePatcher>(numFixupLevels);
+    VTablePatcher& vtablePatcher = *vtablePatcherOwner.get();
 
     const uint32_t kernelLevel = 0;
     uint8_t currentLevel = getCurrentFixupLevel();
@@ -3829,9 +3458,133 @@
     }
 
     // Now that we've processes all rebases/binds, patch all the vtables
-    this->patchVTables(kernelMA, kernelID, dylibsToSymbols, missingBindLocations);
+
+    // Add all the collections to the vtable patcher
+    if ( existingKernelCollection != nullptr ) {
+        // The baseKC for x86_64 has __HIB mapped first , so we need to get either the __DATA or __TEXT depending on what is earliest
+        // The kernel base address is still __TEXT, even if __DATA or __HIB is mapped prior to that.
+        // The loader may have loaded something before __TEXT, but the existingKernelCollection pointer still corresponds to __TEXT
+        __block uint64_t baseAddress = ~0ULL;
+        existingKernelCollection->forEachSegment(^(const dyld3::MachOAnalyzer::SegmentInfo& info, bool& stop) {
+            baseAddress = std::min(baseAddress, info.vmAddr);
+        });
+
+        // The existing collection is a pointer to the mach_header for the baseKC, but __HIB and other segments may be before that
+        // Offset those here
+        uint64_t basePointerOffset = existingKernelCollection->preferredLoadAddress() - baseAddress;
+        const uint8_t* basePointer = (uint8_t*)existingKernelCollection - basePointerOffset;
+
+        vtablePatcher.addKernelCollection(existingKernelCollection, Options::AppCacheKind::kernel,
+                                          basePointer, baseAddress);
+    }
+
+    if ( pageableKernelCollection != nullptr ) {
+        // The baseKC for x86_64 has __HIB mapped first , so we need to get either the __DATA or __TEXT depending on what is earliest
+        // The kernel base address is still __TEXT, even if __DATA or __HIB is mapped prior to that.
+        // The loader may have loaded something before __TEXT, but the existingKernelCollection pointer still corresponds to __TEXT
+        __block uint64_t baseAddress = ~0ULL;
+        pageableKernelCollection->forEachSegment(^(const dyld3::MachOAnalyzer::SegmentInfo& info, bool& stop) {
+            baseAddress = std::min(baseAddress, info.vmAddr);
+        });
+
+        // The existing collection is a pointer to the mach_header for the baseKC, but __HIB and other segments may be before that
+        // Offset those here
+        uint64_t basePointerOffset = pageableKernelCollection->preferredLoadAddress() - baseAddress;
+        const uint8_t* basePointer = (uint8_t*)pageableKernelCollection - basePointerOffset;
+
+        vtablePatcher.addKernelCollection(pageableKernelCollection, Options::AppCacheKind::pageableKC,
+                                          basePointer, baseAddress);
+    }
+
+    // Also add our KC
+    vtablePatcher.addKernelCollection((const dyld3::MachOAppCache*)cacheHeader.header, appCacheOptions.cacheKind,
+                                      (const uint8_t*)_fullAllocatedBuffer, cacheBaseAddress);
+
+    // Add all the dylibs to the patcher
+    {
+        if ( existingKernelCollection != nullptr ) {
+            uint8_t fixupLevel = getFixupLevel(Options::AppCacheKind::kernel);
+
+            __block std::map<std::string, std::vector<std::string>> kextDependencies;
+            kextDependencies[kernelID] = {};
+            existingKernelCollection->forEachPrelinkInfoLibrary(_diagnostics,
+                                                                ^(const char *bundleName, const char* relativePath,
+                                                                  const std::vector<const char *> &deps) {
+                std::vector<std::string>& dependencies = kextDependencies[bundleName];
+                dependencies.insert(dependencies.end(), deps.begin(), deps.end());
+            });
+
+            existingKernelCollection->forEachDylib(_diagnostics, ^(const dyld3::MachOAnalyzer *ma, const char *dylibID, bool &stop) {
+                auto depsIt = kextDependencies.find(dylibID);
+                assert(depsIt != kextDependencies.end());
+                vtablePatcher.addDylib(_diagnostics, ma, dylibID, depsIt->second, fixupLevel);
+            });
+        }
+
+        if ( pageableKernelCollection != nullptr ) {
+            uint8_t fixupLevel = getFixupLevel(Options::AppCacheKind::pageableKC);
+
+            __block std::map<std::string, std::vector<std::string>> kextDependencies;
+            pageableKernelCollection->forEachPrelinkInfoLibrary(_diagnostics,
+                                                                ^(const char *bundleName, const char* relativePath,
+                                                                  const std::vector<const char *> &deps) {
+                std::vector<std::string>& dependencies = kextDependencies[bundleName];
+                dependencies.insert(dependencies.end(), deps.begin(), deps.end());
+            });
+
+            pageableKernelCollection->forEachDylib(_diagnostics, ^(const dyld3::MachOAnalyzer *ma, const char *dylibID, bool &stop) {
+                auto depsIt = kextDependencies.find(dylibID);
+                assert(depsIt != kextDependencies.end());
+                vtablePatcher.addDylib(_diagnostics, ma, dylibID, depsIt->second, fixupLevel);
+            });
+        }
+
+        forEachCacheDylib(^(const dyld3::MachOAnalyzer *ma, const std::string &dylibID, DylibStripMode stripMode,
+                            const std::vector<std::string> &dependencies, Diagnostics& dylibDiag, bool &stop) {
+            vtablePatcher.addDylib(dylibDiag, ma, dylibID, dependencies, currentLevel);
+        });
+    }
+
+    vtablePatcher.findMetaclassDefinitions(dylibsToSymbols, kernelID, kernelMA, appCacheOptions.cacheKind);
+    vtablePatcher.findExistingFixups(_diagnostics, existingKernelCollection, pageableKernelCollection);
     if ( _diagnostics.hasError() )
         return;
+
+    // Add vtables from the base KC if we have one
+    if ( existingKernelCollection != nullptr ) {
+        vtablePatcher.findBaseKernelVTables(_diagnostics, existingKernelCollection, dylibsToSymbols);
+        if ( _diagnostics.hasError() )
+            return;
+    }
+
+    // Add vtables from the pageable KC if we have one
+    if ( pageableKernelCollection != nullptr ) {
+        vtablePatcher.findPageableKernelVTables(_diagnostics, pageableKernelCollection, dylibsToSymbols);
+        if ( _diagnostics.hasError() )
+            return;
+    }
+
+    // Add vables from our level
+    vtablePatcher.findVTables(currentLevel, kernelMA, dylibsToSymbols, _aslrTracker, missingBindLocations);
+
+    // Don't run the patcher if we have a failure finding the vtables
+    if ( vtablePatcher.hasError() ) {
+        _diagnostics.error("One or more binaries has an error which prevented linking.  See other errors.");
+        return;
+    }
+
+    // Now patch all of the vtables.
+    vtablePatcher.patchVTables(_diagnostics, missingBindLocations, _aslrTracker, currentLevel);
+    if ( _diagnostics.hasError() )
+        return;
+
+    if ( vtablePatcher.hasError() ) {
+        _diagnostics.error("One or more binaries has an error which prevented linking.  See other errors.");
+        return;
+    }
+
+    // FIXME: We could move vtablePatcherOwner to a worker thread to be destroyed
+    vtablePatcherOwner.reset();
 
     // Also error out if we have an error on any of the dylib diagnostic objects
 
@@ -4046,9 +3799,11 @@
         // We have a dyld_chained_starts_in_image plus an offset for each segment
         dyld_chained_starts_in_image* startsInImage = (dyld_chained_starts_in_image*)byteBuffer.makeSpace(sizeof(dyld_chained_starts_in_image) + (segmentCount * sizeof(uint32_t)));
 
+        const uint8_t* endOfStarts = nullptr;
         for (SegmentFixups& segmentFixups : startsInSegments) {
             uint64_t startsInSegmentByteSize = sizeof(dyld_chained_starts_in_segment) + (segmentFixups.numPagesToFixup * sizeof(uint16_t));
             dyld_chained_starts_in_segment* startsInSegment = (dyld_chained_starts_in_segment*)byteBuffer.makeSpace(startsInSegmentByteSize);
+            endOfStarts = (const uint8_t*)startsInSegment + startsInSegmentByteSize;
 
             segmentFixups.starts            = startsInSegment;
             segmentFixups.startsByteSize    = startsInSegmentByteSize;
@@ -4274,8 +4029,6 @@
 
         if ( dataConstRegion.sizeInUse != 0 )
             addSegmentStarts(dataConstRegion);
-        if ( dataSptmRegion.sizeInUse != 0 )
-            addSegmentStarts(dataSptmRegion);
         if ( branchGOTsRegion.sizeInUse != 0 )
             addSegmentStarts(branchGOTsRegion);
         if ( readWriteRegion.sizeInUse != 0 )
@@ -4335,151 +4088,6 @@
 #endif
 }
 
-void AppCacheBuilder::getRegionOrder(bool dataRegionFirstInVMOrder,
-                                     bool hibernateRegionFirstInVMOrder,
-                                     std::vector<AlignedRegion>& fileOrder,
-                                     std::vector<AlignedRegion>& vmOrder,
-                                     std::map<const Region*, uint32_t>& sectionsToAddToRegions)
-{
-    if ( hibernateRegionFirstInVMOrder ) {
-        vmOrder.emplace_back(&hibernateRegion, 14, 14);
-        // Add a section too
-        sectionsToAddToRegions[&hibernateRegion] = 1;
-    } else if ( dataRegionFirstInVMOrder ) {
-        if ( prelinkInfoDict != nullptr ) {
-            vmOrder.emplace_back(&prelinkInfoRegion, 14, 14);
-        }
-        if ( readWriteRegion.sizeInUse != 0 ) {
-            vmOrder.emplace_back(&readWriteRegion, 14, 14);
-        }
-    }
-
-    // Cache header (__TEXT)
-    vmOrder.emplace_back(&cacheHeaderRegion, 14, 14);
-    fileOrder.emplace_back(&cacheHeaderRegion, 14, 14);
-
-    // Split seg __TEXT (ie, __PRELINK_TEXT)
-    {
-        vmOrder.emplace_back(&readOnlyTextRegion, 14, 14);
-        fileOrder.emplace_back(&readOnlyTextRegion, 14, 14);
-        // Add a section too
-        sectionsToAddToRegions[&readOnlyTextRegion] = 1;
-    }
-
-    // __DATA_CONST
-    if ( dataConstRegion.sizeInUse != 0 ) {
-        vmOrder.emplace_back(&dataConstRegion, 14, 14);
-        fileOrder.emplace_back(&dataConstRegion, 14, 14);
-    }
-
-    // __DATA_SPTM
-    if ( dataSptmRegion.sizeInUse != 0 ) {
-        vmOrder.emplace_back(&dataSptmRegion, 14, 14);
-        fileOrder.emplace_back(&dataSptmRegion, 14, 14);
-    }
-
-    // Split seg __TEXT_EXEC
-    if ( readExecuteRegion.sizeInUse != 0 ) {
-        vmOrder.emplace_back(&readExecuteRegion, 14, 14);
-        fileOrder.emplace_back(&readExecuteRegion, 14, 14);
-    }
-
-    // __BRANCH_STUBS
-    if ( branchStubsRegion.bufferSize != 0 ) {
-        vmOrder.emplace_back(&branchStubsRegion, 14, 14);
-        fileOrder.emplace_back(&branchStubsRegion, 14, 14);
-    }
-
-    // __TEXT_BOOT_EXEC
-    if ( textBootExecRegion.sizeInUse != 0 ) {
-        vmOrder.emplace_back(&textBootExecRegion, 14, 14);
-        fileOrder.emplace_back(&textBootExecRegion, 14, 14);
-    }
-
-    // __BRANCH_GOTS
-    if ( branchGOTsRegion.bufferSize != 0 ) {
-        vmOrder.emplace_back(&branchGOTsRegion, 14, 14);
-        fileOrder.emplace_back(&branchGOTsRegion, 14, 14);
-    }
-
-    // -sectcreate
-    // Align to 16k before we lay out all contiguous regions
-    if ( !customSegments.empty() ) {
-        uint32_t alignFileBefore = 14;
-        for (CustomSegment& customSegment : customSegments) {
-            Region& region = *customSegment.parentRegion;
-            vmOrder.emplace_back(&region, 0, 0);
-            fileOrder.emplace_back(&region, alignFileBefore, 0);
-            alignFileBefore = 0;
-
-            // Maybe add sections too
-            uint32_t sectionsToAdd = 0;
-            if ( customSegment.sections.size() > 1 ) {
-                // More than one section, so they all need names
-                sectionsToAdd = (uint32_t)customSegment.sections.size();
-            } else if ( !customSegment.sections.front().sectionName.empty() ) {
-                // Only one section, but it has a name
-                sectionsToAdd = 1;
-            }
-            sectionsToAddToRegions[&region] = sectionsToAdd;
-        }
-
-        // Align the last region after
-        vmOrder.back().alignmentAfter = 14;
-        fileOrder.back().alignmentAfter = 14;
-    }
-
-    // __PRELINK_INFO
-    if ( prelinkInfoDict != nullptr )
-    {
-        fileOrder.emplace_back(&prelinkInfoRegion, 14, 14);
-        if ( !dataRegionFirstInVMOrder )
-            vmOrder.emplace_back(&prelinkInfoRegion, 14, 14);
-        // Add a section too
-        sectionsToAddToRegions[&prelinkInfoRegion] = 1;
-    }
-
-    // Split seg __DATA
-    if ( readWriteRegion.sizeInUse != 0 ) {
-        fileOrder.emplace_back(&readWriteRegion, 14, 14);
-        if ( !dataRegionFirstInVMOrder ) {
-            vmOrder.emplace_back(&readWriteRegion, 14, 14);
-        }
-    }
-
-    // Split seg __HIB
-    // Align to 16k
-    if ( hibernateRegion.sizeInUse != 0 ) {
-        fileOrder.emplace_back(&hibernateRegion, 14, 14);
-        // VM offset was already handled earlier
-    }
-
-    // Non split seg regions
-    // Align to 16k before we lay out all contiguous regions
-    if ( !nonSplitSegRegions.empty() ) {
-        uint32_t alignFileBefore = 14;
-        for (Region& region : nonSplitSegRegions) {
-            vmOrder.emplace_back(&region, 0, 0);
-            fileOrder.emplace_back(&region, alignFileBefore, 0);
-            alignFileBefore = 0;
-        }
-
-        // Align the last region after
-        vmOrder.back().alignmentAfter = 14;
-        fileOrder.back().alignmentAfter = 14;
-    }
-
-    // __LINKEDIT
-    vmOrder.emplace_back(&_readOnlyRegion, 14, 14);
-    fileOrder.emplace_back(&_readOnlyRegion, 14, 14);
-
-    // __LINKEDIT fixups sub region
-    if ( fixupsSubRegion.sizeInUse != 0 ) {
-        vmOrder.emplace_back(&fixupsSubRegion, 14, 14);
-        fileOrder.emplace_back(&fixupsSubRegion, 14, 14);
-    }
-}
-
 void AppCacheBuilder::allocateBuffer()
 {
     // Whether to order the regions __TEXT, __DATA, __LINKEDIT or __DATA, __TEXT, __LINKEDIT in VM address order
@@ -4490,7 +4098,7 @@
             assert(0 && "Cache kind should have been set");
             break;
         case Options::AppCacheKind::kernel:
-            if ( hibernateRegion.sizeInUse != 0 )
+            if ( hibernateAddress != 0 )
                 hibernateRegionFirstInVMOrder = true;
             break;
         case Options::AppCacheKind::pageableKC:
@@ -4504,11 +4112,228 @@
             break;
     }
 
-    std::vector<AlignedRegion> fileOrder;
-    std::vector<AlignedRegion> vmOrder;
+    // Count how many bytes we need from all our regions
+    __block uint64_t numRegionFileBytes = 0;
+    __block uint64_t numRegionVMBytes = 0;
+
+    std::vector<std::pair<Region*, uint64_t>> regions;
+    std::vector<std::pair<Region*, uint64_t>> regionsVMOrder;
     std::map<const Region*, uint32_t> sectionsToAddToRegions;
-    getRegionOrder(dataRegionFirstInVMOrder, hibernateRegionFirstInVMOrder,
-                   fileOrder, vmOrder, sectionsToAddToRegions);
+
+    if ( hibernateRegionFirstInVMOrder ) {
+        regionsVMOrder.push_back({ &hibernateRegion, numRegionVMBytes });
+        // Pad out the VM offset so that the cache header starts where the base address
+        // really should be
+        uint64_t paddedSize = cacheBaseAddress - hibernateAddress;
+        if ( hibernateRegion.bufferSize > paddedSize ) {
+            _diagnostics.error("Could not lay out __HIB segment");
+            return;
+        }
+        numRegionVMBytes = paddedSize;
+        // Set the base address to the hibernate address so that we actually put the
+        // hibernate segment there
+        cacheBaseAddress = hibernateAddress;
+
+        // Add a section too
+        sectionsToAddToRegions[&hibernateRegion] = 1;
+    } else if ( dataRegionFirstInVMOrder ) {
+        if ( prelinkInfoDict != nullptr ) {
+            numRegionVMBytes = align(numRegionVMBytes, 14);
+            regionsVMOrder.push_back({ &prelinkInfoRegion, numRegionVMBytes });
+            numRegionVMBytes += prelinkInfoRegion.bufferSize;
+        }
+        if ( readWriteRegion.sizeInUse != 0 ) {
+            numRegionVMBytes = align(numRegionVMBytes, 14);
+            regionsVMOrder.push_back({ &readWriteRegion, numRegionVMBytes });
+            numRegionVMBytes += readWriteRegion.bufferSize;
+        }
+    }
+
+    // Cache header
+    numRegionVMBytes = align(numRegionVMBytes, 14);
+    regions.push_back({ &cacheHeaderRegion, 0 });
+    regionsVMOrder.push_back({ &cacheHeaderRegion, numRegionVMBytes });
+
+    // Split seg __TEXT
+    {
+        // File offset
+        readOnlyTextRegion.cacheFileOffset = numRegionFileBytes;
+        numRegionFileBytes += readOnlyTextRegion.bufferSize;
+        regions.push_back({ &readOnlyTextRegion, 0 });
+        // VM offset
+        numRegionVMBytes = align(numRegionVMBytes, 14);
+        regionsVMOrder.push_back({ &readOnlyTextRegion, numRegionVMBytes });
+        numRegionVMBytes += readOnlyTextRegion.bufferSize;
+
+        // Add a section too
+        sectionsToAddToRegions[&readOnlyTextRegion] = 1;
+    }
+
+    // Split seg __TEXT_EXEC
+    if ( readExecuteRegion.sizeInUse != 0 ) {
+        // File offset
+        readExecuteRegion.cacheFileOffset = numRegionFileBytes;
+        numRegionFileBytes += readExecuteRegion.bufferSize;
+        regions.push_back({ &readExecuteRegion, 0 });
+        // VM offset
+        numRegionVMBytes = align(numRegionVMBytes, 14);
+        regionsVMOrder.push_back({ &readExecuteRegion, numRegionVMBytes });
+        numRegionVMBytes += readExecuteRegion.bufferSize;
+    }
+
+    // __BRANCH_STUBS
+    if ( branchStubsRegion.bufferSize != 0 ) {
+        // File offset
+        branchStubsRegion.cacheFileOffset = numRegionFileBytes;
+        numRegionFileBytes += branchStubsRegion.bufferSize;
+        regions.push_back({ &branchStubsRegion, 0 });
+        // VM offset
+        numRegionVMBytes = align(numRegionVMBytes, 14);
+        regionsVMOrder.push_back({ &branchStubsRegion, numRegionVMBytes });
+        numRegionVMBytes += branchStubsRegion.bufferSize;
+    }
+
+    // __DATA_CONST
+    if ( dataConstRegion.sizeInUse != 0 ) {
+        // File offset
+        dataConstRegion.cacheFileOffset = numRegionFileBytes;
+        numRegionFileBytes += dataConstRegion.bufferSize;
+        regions.push_back({ &dataConstRegion, 0 });
+        // VM offset
+        numRegionVMBytes = align(numRegionVMBytes, 14);
+        regionsVMOrder.push_back({ &dataConstRegion, numRegionVMBytes });
+        numRegionVMBytes += dataConstRegion.bufferSize;
+    }
+
+    // __BRANCH_GOTS
+    if ( branchGOTsRegion.bufferSize != 0 ) {
+        // File offset
+        branchGOTsRegion.cacheFileOffset = numRegionFileBytes;
+        numRegionFileBytes += branchGOTsRegion.bufferSize;
+        regions.push_back({ &branchGOTsRegion, 0 });
+        // VM offset
+        numRegionVMBytes = align(numRegionVMBytes, 14);
+        regionsVMOrder.push_back({ &branchGOTsRegion, numRegionVMBytes });
+        numRegionVMBytes += branchGOTsRegion.bufferSize;
+    }
+
+    // -sectcreate
+    // Align to 16k before we lay out all contiguous regions
+    numRegionFileBytes = align(numRegionFileBytes, 14);
+    for (CustomSegment& customSegment : customSegments) {
+        Region& region = *customSegment.parentRegion;
+
+        region.cacheFileOffset = numRegionFileBytes;
+        numRegionFileBytes += region.bufferSize;
+        regions.push_back({ &region, 0 });
+        // VM offset
+        // Note we can't align the vm offset in here
+        assert( (numRegionVMBytes % 4096) == 0);
+        regionsVMOrder.push_back({ &region, numRegionVMBytes });
+        numRegionVMBytes += region.bufferSize;
+
+        // Maybe add sections too
+        uint32_t sectionsToAdd = 0;
+        if ( customSegment.sections.size() > 1 ) {
+            // More than one section, so they all need names
+            sectionsToAdd = (uint32_t)customSegment.sections.size();
+        } else if ( !customSegment.sections.front().sectionName.empty() ) {
+            // Only one section, but it has a name
+            sectionsToAdd = 1;
+        }
+        sectionsToAddToRegions[&region] = sectionsToAdd;
+    }
+    numRegionVMBytes = align(numRegionVMBytes, 14);
+
+    // __PRELINK_INFO
+    // Align to 16k
+    numRegionFileBytes = align(numRegionFileBytes, 14);
+    if ( prelinkInfoDict != nullptr )
+    {
+        // File offset
+        prelinkInfoRegion.cacheFileOffset = numRegionFileBytes;
+        numRegionFileBytes += prelinkInfoRegion.bufferSize;
+        regions.push_back({ &prelinkInfoRegion, 0 });
+
+        if ( !dataRegionFirstInVMOrder ) {
+            // VM offset
+            numRegionVMBytes = align(numRegionVMBytes, 14);
+            regionsVMOrder.push_back({ &prelinkInfoRegion, numRegionVMBytes });
+            numRegionVMBytes += prelinkInfoRegion.bufferSize;
+        }
+
+        // Add a section too
+        sectionsToAddToRegions[&prelinkInfoRegion] = 1;
+    }
+
+    // Split seg __DATA
+    // Align to 16k
+    numRegionFileBytes = align(numRegionFileBytes, 14);
+    if ( readWriteRegion.sizeInUse != 0 ) {
+        // File offset
+        readWriteRegion.cacheFileOffset = numRegionFileBytes;
+        numRegionFileBytes += readWriteRegion.bufferSize;
+        regions.push_back({ &readWriteRegion, 0 });
+
+        if ( !dataRegionFirstInVMOrder ) {
+            // VM offset
+            numRegionVMBytes = align(numRegionVMBytes, 14);
+            regionsVMOrder.push_back({ &readWriteRegion, numRegionVMBytes });
+            numRegionVMBytes += readWriteRegion.bufferSize;
+        }
+    }
+
+    // Split seg __HIB
+    // Align to 16k
+    numRegionFileBytes = align(numRegionFileBytes, 14);
+    if ( hibernateRegion.sizeInUse != 0 ) {
+        // File offset
+        hibernateRegion.cacheFileOffset = numRegionFileBytes;
+        numRegionFileBytes += hibernateRegion.bufferSize;
+        regions.push_back({ &hibernateRegion, 0 });
+
+        // VM offset was already handled earlier
+    }
+
+    // Non split seg regions
+    // Align to 16k before we lay out all contiguous regions
+    numRegionFileBytes = align(numRegionFileBytes, 14);
+    for (Region& region : nonSplitSegRegions) {
+        region.cacheFileOffset = numRegionFileBytes;
+        numRegionFileBytes += region.bufferSize;
+        regions.push_back({ &region, 0 });
+        // VM offset
+        // Note we can't align the vm offset in here
+        assert( (numRegionVMBytes % 4096) == 0);
+        regionsVMOrder.push_back({ &region, numRegionVMBytes });
+        numRegionVMBytes += region.bufferSize;
+    }
+    numRegionVMBytes = align(numRegionVMBytes, 14);
+
+    // __LINKEDIT
+    // Align to 16k
+    // File offset
+    numRegionFileBytes = align(numRegionFileBytes, 14);
+    _readOnlyRegion.cacheFileOffset = numRegionFileBytes;
+    numRegionFileBytes += _readOnlyRegion.bufferSize;
+    regions.push_back({ &_readOnlyRegion, 0 });
+    // VM offset
+    numRegionVMBytes = align(numRegionVMBytes, 14);
+    regionsVMOrder.push_back({ &_readOnlyRegion, numRegionVMBytes });
+    numRegionVMBytes += _readOnlyRegion.bufferSize;
+
+    // __LINKEDIT fixups sub region
+    // Align to 16k
+    numRegionFileBytes = align(numRegionFileBytes, 14);
+    if ( fixupsSubRegion.sizeInUse != 0 ) {
+        fixupsSubRegion.cacheFileOffset = numRegionFileBytes;
+        numRegionFileBytes += fixupsSubRegion.bufferSize;
+        //regions.push_back({ &fixupsSubRegion, 0 });
+
+        // VM offset
+        regionsVMOrder.push_back({ &fixupsSubRegion, numRegionVMBytes });
+        numRegionVMBytes += fixupsSubRegion.bufferSize;
+    }
 
     const thread_command* unixThread = nullptr;
     if (const DylibInfo* dylib = getKernelStaticExecutableInputFile()) {
@@ -4567,19 +4392,13 @@
         }
 
         // Add an LC_SEGMENT_64 for each region
-        std::unordered_map<const Region*, uint64_t> regionLoadCommandOffsets;
-        for ( const AlignedRegion& region : fileOrder ) {
-            // The fixups sub region doesn't get a load command, as its a range inside LINKEDIT
-            if ( region.region == &fixupsSubRegion )
-                continue;
-
-            regionLoadCommandOffsets[region.region] = cacheHeaderSize + cacheLoadCommandsSize;
-
+        for (auto& regionAndOffset : regions) {
             ++cacheNumLoadCommands;
+            regionAndOffset.second = cacheHeaderSize + cacheLoadCommandsSize;
             cacheLoadCommandsSize += sizeof(segment_command_64);
 
             // Add space for any sections too
-            auto sectionIt = sectionsToAddToRegions.find(region.region);
+            auto sectionIt = sectionsToAddToRegions.find(regionAndOffset.first);
             if ( sectionIt != sectionsToAddToRegions.end() ) {
                 uint32_t numSections = sectionIt->second;
                 cacheLoadCommandsSize += sizeof(section_64) * numSections;
@@ -4601,51 +4420,6 @@
         // Align the app cache header before the rest of the bytes
         cacheHeaderRegionSize = align(cacheHeaderRegionSize, 14);
 
-        // Cache header
-        cacheHeaderRegion.bufferSize            = cacheHeaderRegionSize;
-        cacheHeaderRegion.sizeInUse             = cacheHeaderRegion.bufferSize;
-        cacheHeaderRegion.cacheFileOffset       = 0;
-        cacheHeaderRegion.initProt              = VM_PROT_READ;
-        cacheHeaderRegion.maxProt               = VM_PROT_READ;
-        cacheHeaderRegion.name                  = "__TEXT";
-
-        // Walk all the regions and compute the total file and VM bytes
-        uint64_t numRegionVMBytes = 0;
-        {
-            uint64_t vmAddr = cacheBaseAddress;
-            for ( AlignedRegion& alignedRegion : vmOrder ) {
-                if ( alignedRegion.alignmentBefore != 0 )
-                    vmAddr = align(vmAddr, alignedRegion.alignmentBefore);
-
-                Region* region = alignedRegion.region;
-                region->unslidLoadAddress = vmAddr;
-                vmAddr += region->bufferSize;
-
-                if ( alignedRegion.alignmentAfter != 0 )
-                    vmAddr = align(vmAddr, alignedRegion.alignmentAfter);
-            }
-
-            numRegionVMBytes = vmAddr - cacheBaseAddress;
-        }
-
-        uint64_t numRegionFileBytes = 0;
-        {
-            uint64_t fileOffset = 0;
-            for ( AlignedRegion& alignedRegion : fileOrder ) {
-                if ( alignedRegion.alignmentBefore != 0 )
-                    fileOffset = align(fileOffset, alignedRegion.alignmentBefore);
-
-                Region* region = alignedRegion.region;
-                region->cacheFileOffset = fileOffset;
-                fileOffset += region->bufferSize;
-
-                if ( alignedRegion.alignmentAfter != 0 )
-                    fileOffset = align(fileOffset, alignedRegion.alignmentAfter);
-            }
-
-            numRegionFileBytes = fileOffset;
-        }
-
         assert(numRegionFileBytes <= numRegionVMBytes);
 
         _allocatedBufferSize = cacheHeaderRegionSize + numRegionVMBytes;
@@ -4667,10 +4441,33 @@
 
         // Assign region vm and buffer addresses now that we know the size of
         // the cache header
-        for ( AlignedRegion& alignedRegion : vmOrder ) {
-            Region* region = alignedRegion.region;
-            region->buffer = (uint8_t*)_fullAllocatedBuffer + (region->unslidLoadAddress - cacheBaseAddress);
-        }
+        {
+            // All vm offsets prior to the cache header are already correct
+            // All those after the cache header need to be shifted by the cache
+            // header size
+            bool seenCacheHeader = false;
+            for (const auto& regionAndVMOffset : regionsVMOrder) {
+                Region* region = regionAndVMOffset.first;
+                uint64_t vmOffset = regionAndVMOffset.second;
+                region->unslidLoadAddress = cacheBaseAddress + vmOffset;
+                if ( seenCacheHeader ) {
+                    // Shift by the cache header size
+                    region->unslidLoadAddress += cacheHeaderRegionSize;
+                } else {
+                    // The offset is correct but add in the base address
+                    seenCacheHeader = (region == &cacheHeaderRegion);
+                }
+                region->buffer = (uint8_t*)_fullAllocatedBuffer + (region->unslidLoadAddress - cacheBaseAddress);
+            }
+        }
+
+        // Cache header
+        cacheHeaderRegion.bufferSize            = cacheHeaderRegionSize;
+        cacheHeaderRegion.sizeInUse             = cacheHeaderRegion.bufferSize;
+        cacheHeaderRegion.cacheFileOffset       = 0;
+        cacheHeaderRegion.initProt              = VM_PROT_READ;
+        cacheHeaderRegion.maxProt               = VM_PROT_READ;
+        cacheHeaderRegion.name                  = "__TEXT";
 
 #if 0
         for (const auto& regionAndVMOffset : regionsVMOrder) {
@@ -4702,23 +4499,57 @@
             header.chainedFixups = (linkedit_data_command*)(cacheHeaderRegion.buffer + chainedFixupsOffset);
         }
 
-        for ( AlignedRegion& alignedRegion : fileOrder ) {
-            Region* region = alignedRegion.region;
-            // The fixups sub region doesn't get a load command, as its a range inside LINKEDIT
-            if ( region == &fixupsSubRegion )
-                continue;
-
-            assert(region->initProt != 0);
-            assert(region->maxProt != 0);
-
-            uint64_t loadCommandOffset = regionLoadCommandOffsets.at(region);
-            segment_command_64* loadCommand = (segment_command_64*)(cacheHeaderRegion.buffer + loadCommandOffset);
-            header.segments.push_back({ loadCommand, region });
+        for (auto& regionAndOffset : regions) {
+            assert(regionAndOffset.first->initProt != 0);
+            assert(regionAndOffset.first->maxProt != 0);
+            segment_command_64* loadCommand = (segment_command_64*)(cacheHeaderRegion.buffer + regionAndOffset.second);
+            header.segments.push_back({ loadCommand, regionAndOffset.first });
         }
         for (const auto& dylibAndOffset : dylibs) {
             fileset_entry_command* loadCommand = (fileset_entry_command*)(cacheHeaderRegion.buffer + dylibAndOffset.second);
             header.dylibs.push_back({ loadCommand, dylibAndOffset.first });
         }
+
+        // Move the offsets of all the other regions
+        // Split seg __TEXT
+        readOnlyTextRegion.cacheFileOffset += cacheHeaderRegion.sizeInUse;
+
+        // Split seg __TEXT_EXEC
+        readExecuteRegion.cacheFileOffset += cacheHeaderRegion.sizeInUse;
+
+        // __BRANCH_STUBS
+        branchStubsRegion.cacheFileOffset += cacheHeaderRegion.sizeInUse;
+
+        // Split seg __DATA_CONST
+        dataConstRegion.cacheFileOffset += cacheHeaderRegion.sizeInUse;
+
+        // __BRANCH_GOTS
+        branchGOTsRegion.cacheFileOffset += cacheHeaderRegion.sizeInUse;
+
+        // Split seg __DATA
+        readWriteRegion.cacheFileOffset += cacheHeaderRegion.sizeInUse;
+
+        // Split seg __HIB
+        hibernateRegion.cacheFileOffset += cacheHeaderRegion.sizeInUse;
+
+        // -sectcreate
+        for (Region& region : customDataRegions) {
+            region.cacheFileOffset += cacheHeaderRegion.sizeInUse;
+        }
+
+        // Non split seg regions
+        for (Region& region : nonSplitSegRegions) {
+            region.cacheFileOffset += cacheHeaderRegion.sizeInUse;
+        }
+
+        // __PRELINK_INFO
+        prelinkInfoRegion.cacheFileOffset += cacheHeaderRegion.sizeInUse;
+
+        // __LINKEDIT
+        _readOnlyRegion.cacheFileOffset += cacheHeaderRegion.sizeInUse;
+
+        // __LINKEDIT fixups sub region
+        fixupsSubRegion.cacheFileOffset += cacheHeaderRegion.sizeInUse;
     } else {
         assert(false);
     }
@@ -5215,9 +5046,6 @@
         return;
     }
 
-    // Find stubs to remove, if any
-    parseStubs();
-
     // assign addresses for each segment of each dylib in new cache
     assignSegmentRegionsAndOffsets();
     if ( _diagnostics.hasError() )
@@ -5268,13 +5096,6 @@
                 lastDataRegion = &dataConstRegion;
         }
 
-        if ( dataSptmRegion.sizeInUse != 0 ) {
-            if ( firstDataRegion == nullptr )
-                firstDataRegion = &dataSptmRegion;
-            if ( (lastDataRegion == nullptr) || (dataSptmRegion.buffer > lastDataRegion->buffer) )
-                lastDataRegion = &dataSptmRegion;
-        }
-
         if ( branchGOTsRegion.bufferSize != 0 ) {
             if ( firstDataRegion == nullptr )
                 firstDataRegion = &branchGOTsRegion;
@@ -5308,7 +5129,7 @@
             _aslrTracker.setDataRegion(firstDataRegion->buffer, size);
         }
     }
-    adjustAllImagesForNewSegmentLocations(cacheBaseAddress, nullptr);
+    adjustAllImagesForNewSegmentLocations(cacheBaseAddress, nullptr, nullptr);
     if ( _diagnostics.hasError() )
         return;
 
@@ -5327,17 +5148,12 @@
 
     // optimize away stubs
     uint64_t t6 = mach_absolute_time();
-
-    if ( removeStubs() ) {
-        // Stubs were removed, but we need to rewrite calls which would have gone through those stubs
-        rewriteRemovedStubs();
-    } else {
-        // Stubs weren't removed, so do the existing stub optimizer
-        __block std::vector<StubOptimizerInfo> images;
+    {
+        __block std::vector<std::pair<const mach_header*, const char*>> images;
         forEachCacheDylib(^(const dyld3::MachOAnalyzer *ma, const std::string &dylibID,
                             DylibStripMode stripMode, const std::vector<std::string>& dependencies,
                             Diagnostics& dylibDiag, bool& stop) {
-            images.push_back({ ma, dylibID.c_str(), nullptr, nullptr });
+            images.push_back({ ma, dylibID.c_str() });
         });
         // FIXME: Should we keep the same never stub eliminate symbols?  Eg, for gmalloc.
         const char* const neverStubEliminateSymbols[] = {
@@ -5346,8 +5162,8 @@
 
         uint64_t cacheUnslidAddr = cacheBaseAddress;
         int64_t cacheSlide = (long)_fullAllocatedBuffer - cacheUnslidAddr;
-        std::unordered_map<uint64_t, std::pair<uint64_t, uint8_t*>> stubsToIslandAddr;
-        optimizeAwayStubs(images, cacheSlide, nullptr, stubsToIslandAddr, neverStubEliminateSymbols);
+        optimizeAwayStubs(images, cacheSlide, cacheUnslidAddr,
+                          nullptr, neverStubEliminateSymbols);
     }
 
     // FIPS seal corecrypto, This must be done after stub elimination (so that __TEXT,__text is not changed after sealing)
@@ -5467,213 +5283,6 @@
     }
 }
 
-static void getSectionLayout(const dyld3::MachOAnalyzer* ma,
-                             std::vector<uint64_t>& sectionAddresses,
-                             std::vector<uint8_t*>& sectionBuffers,
-                             uint32_t& authStubSectionIndex)
-{
-    // section index 0 refers to mach_header
-    sectionAddresses.push_back(ma->preferredLoadAddress());
-    sectionBuffers.push_back(nullptr);
-
-    intptr_t slide = ma->getSlide();
-    ma->forEachSection(^(const dyld3::MachOAnalyzer::SectionInfo& sectInfo, bool malformedSectionRange, bool& stop) {
-        if ( !strcmp(sectInfo.segInfo.segName, "__TEXT_EXEC") && !strcmp(sectInfo.sectName, "__auth_stubs") )
-            authStubSectionIndex = (uint32_t)sectionAddresses.size();
-        sectionAddresses.push_back(sectInfo.sectAddr);
-        sectionBuffers.push_back((uint8_t*)sectInfo.sectAddr + slide);
-    });
-}
-
-// Auth stubs will load a value then jump to it.  This returns the list of locations they jump to
-static void getAuthStubTargets(Diagnostics& diag, const dyld3::MachOAnalyzer* ma,
-                               std::string_view dylibID,
-                               const std::vector<uint64_t>& sectionAddresses,
-                               const std::vector<uint8_t*>& sectionBuffers,
-                               uint32_t stubSectionIndex,
-                               std::map<uint64_t, uint64_t>& stubToTargetMap)
-{
-    uint32_t splitSegSize = 0;
-    const uint8_t* infoStart = (const uint8_t*)ma->getSplitSeg(splitSegSize);
-    const uint8_t* infoEnd = infoStart + splitSegSize;
-    if ( *infoStart++ != DYLD_CACHE_ADJ_V2_FORMAT ) {
-        diag.error("malformed split seg info in %s", dylibID.data());
-        return;
-    }
-
-    // Whole         :== <count> FromToSection+
-    // FromToSection :== <from-sect-index> <to-sect-index> <count> ToOffset+
-    // ToOffset      :== <to-sect-offset-delta> <count> FromOffset+
-    // FromOffset    :== <kind> <count> <from-sect-offset-delta>
-    const uint8_t* p = infoStart;
-    uint64_t sectionCount = read_uleb128(p, infoEnd);
-    for (uint64_t i=0; i < sectionCount; ++i) {
-        uint64_t fromSectionIndex = read_uleb128(p, infoEnd);
-        uint64_t toSectionIndex = read_uleb128(p, infoEnd);
-        uint64_t toOffsetCount = read_uleb128(p, infoEnd);
-        uint64_t toSectionOffset = 0;
-        for (uint64_t j=0; j < toOffsetCount; ++j) {
-            uint64_t toSectionDelta = read_uleb128(p, infoEnd);
-            uint64_t fromOffsetCount = read_uleb128(p, infoEnd);
-            toSectionOffset += toSectionDelta;
-            for (uint64_t k=0; k < fromOffsetCount; ++k) {
-                uint64_t kind = read_uleb128(p, infoEnd);
-                if ( kind > 13 ) {
-                    diag.error("bad kind (%llu) value in %s\n", kind, dylibID.data());
-                }
-                uint64_t fromSectDeltaCount = dyld3::MachOFile::read_uleb128(diag, p, infoEnd);
-                if ( diag.hasError() )
-                    return;
-                uint64_t fromSectionOffset = 0;
-                for (uint64_t l=0; l < fromSectDeltaCount; ++l) {
-                    uint64_t delta = dyld3::MachOFile::read_uleb128(diag, p, infoEnd);
-                    if ( diag.hasError() )
-                        return;
-                    fromSectionOffset += delta;
-                    if ( fromSectionIndex == stubSectionIndex ) {
-                        // The stub is 16-bytes in size, and contains the stub fixup here.
-                        // We need to work out the stub for the fixup
-                        uint64_t stubOffset = fromSectionOffset & ~0xF;
-                        uint64_t stubAddr = sectionAddresses[fromSectionIndex] + stubOffset;
-
-                        uint64_t* gotPtr = (uint64_t*)(sectionBuffers[toSectionIndex] + toSectionOffset);
-                        uint64_t gotTargetAddr = *gotPtr;
-                        printf("");
-
-                        stubToTargetMap[stubAddr] = gotTargetAddr;
-                    }
-                }
-            }
-        }
-    }
-}
-
-static void rewriteBranchesToStubs(Diagnostics& diag, const dyld3::MachOAnalyzer* ma,
-                                   std::string_view dylibID,
-                                   const std::vector<uint64_t>& sectionAddresses,
-                                   const std::vector<uint8_t*>& sectionBuffers,
-                                   uint32_t stubSectionIndex,
-                                   const std::map<uint64_t, uint64_t>& stubToTargetMap)
-{
-    static const int64_t b128MegLimit = 0x07FFFFFF;
-
-    uint32_t splitSegSize = 0;
-    const uint8_t* infoStart = (const uint8_t*)ma->getSplitSeg(splitSegSize);
-    const uint8_t* infoEnd = infoStart + splitSegSize;
-    if ( *infoStart++ != DYLD_CACHE_ADJ_V2_FORMAT ) {
-        diag.error("malformed split seg info in %s", dylibID.data());
-        return;
-    }
-
-    // Whole         :== <count> FromToSection+
-    // FromToSection :== <from-sect-index> <to-sect-index> <count> ToOffset+
-    // ToOffset      :== <to-sect-offset-delta> <count> FromOffset+
-    // FromOffset    :== <kind> <count> <from-sect-offset-delta>
-    const uint8_t* p = infoStart;
-    uint64_t sectionCount = read_uleb128(p, infoEnd);
-    for (uint64_t i=0; i < sectionCount; ++i) {
-        uint64_t fromSectionIndex = read_uleb128(p, infoEnd);
-        uint64_t toSectionIndex = read_uleb128(p, infoEnd);
-        uint64_t toOffsetCount = read_uleb128(p, infoEnd);
-        uint64_t toSectionOffset = 0;
-        for (uint64_t j=0; j < toOffsetCount; ++j) {
-            uint64_t toSectionDelta = read_uleb128(p, infoEnd);
-            uint64_t fromOffsetCount = read_uleb128(p, infoEnd);
-            toSectionOffset += toSectionDelta;
-            for (uint64_t k=0; k < fromOffsetCount; ++k) {
-                uint64_t kind = read_uleb128(p, infoEnd);
-                if ( kind > 13 ) {
-                    diag.error("bad kind (%llu) value in %s\n", kind, dylibID.data());
-                }
-                uint64_t fromSectDeltaCount = dyld3::MachOFile::read_uleb128(diag, p, infoEnd);
-                if ( diag.hasError() )
-                    return;
-                uint64_t fromSectionOffset = 0;
-                for (uint64_t l=0; l < fromSectDeltaCount; ++l) {
-                    uint64_t delta = dyld3::MachOFile::read_uleb128(diag, p, infoEnd);
-                    if ( diag.hasError() )
-                        return;
-                    fromSectionOffset += delta;
-                    if ( toSectionIndex == stubSectionIndex ) {
-                        // The stub is 16-bytes in size, and contains the stub fixup here.
-                        // We need to work out the stub for the fixup
-                        uint32_t* instrPtr = (uint32_t*)(sectionBuffers[fromSectionIndex] + fromSectionOffset);
-                        uint64_t instrAddr = sectionAddresses[fromSectionIndex] + fromSectionOffset;
-                        uint64_t stubAddr = sectionAddresses[toSectionIndex] + toSectionOffset;
-
-                        auto it = stubToTargetMap.find(stubAddr);
-                        if ( it == stubToTargetMap.end() ) {
-                            diag.error("couldn't find stub at 0x%llx, for branch 0x%llx in %s\n", stubAddr, instrAddr, dylibID.data());
-                        }
-
-                        uint64_t finalTargetAddr = it->second;
-
-                        if ( kind != DYLD_CACHE_ADJ_V2_ARM64_BR26 ) {
-                            diag.error("bad kind (%llu) value in %s\n", kind, dylibID.data());
-                            return;
-                        }
-                        // skip all but BL or B
-                        uint32_t& instruction = *instrPtr;
-                        if ( (instruction & 0x7C000000) != 0x14000000 ) {
-                            diag.error("bad instruction (0x%x) value in %s\n", instruction, dylibID.data());
-                            return;
-                        }
-
-                        int64_t deltaToFinalTarget = finalTargetAddr - instrAddr;
-                        // if final target within range, change to branch there directly
-                        if ( (deltaToFinalTarget > -b128MegLimit) && (deltaToFinalTarget < b128MegLimit) ) {
-                            instruction = (instruction & 0xFC000000) | ((deltaToFinalTarget >> 2) & 0x03FFFFFF);
-                        } else {
-                            diag.error("branch (%llx -> %llx) out of reach (%llx) in %s\n", fromSectionOffset, toSectionOffset,
-                                       deltaToFinalTarget, dylibID.data());
-                        }
-                    }
-                }
-            }
-        }
-    }
-}
-
-void AppCacheBuilder::rewriteRemovedStubs()
-{
-    if ( _diagnostics.hasError() )
-        return;
-
-    for (AppCacheDylibInfo& dylib : sortedDylibs) {
-        if ( !dylib._coalescer.auth_stubs.sectionIsObliterated )
-            continue;
-
-        const dyld3::MachOAnalyzer* ma = nullptr;
-        for (const SegmentMappingInfo& loc : dylib.cacheLocation) {
-            if ( !strcmp(loc.segName, "__TEXT") ) {
-                // Assume __TEXT contains the mach header
-                ma = (const dyld3::MachOAnalyzer*)loc.dstSegment;
-                break;
-            }
-        }
-
-        // We need to find what the auth stubs pointed to, then rewrite all
-        // users of the auth stubs to jump to those locations instead
-        std::vector<uint64_t> sectionAddresses;
-        std::vector<uint8_t*> sectionBuffers;
-        uint32_t authStubSectionIndex = ~0U;
-        getSectionLayout(ma, sectionAddresses, sectionBuffers, authStubSectionIndex);
-
-        std::map<uint64_t, uint64_t> stubToTargetMap;
-        getAuthStubTargets(_diagnostics, dylib.input->mappedFile.mh, dylib.dylibID,
-                           sectionAddresses, sectionBuffers, authStubSectionIndex,
-                           stubToTargetMap);
-        if ( _diagnostics.hasError() )
-            return;
-
-        rewriteBranchesToStubs(_diagnostics, dylib.input->mappedFile.mh, dylib.dylibID,
-                               sectionAddresses, sectionBuffers, authStubSectionIndex,
-                               stubToTargetMap);
-        if ( _diagnostics.hasError() )
-            return;
-    }
-}
-
 void AppCacheBuilder::fipsSign()
 {
     if ( appCacheOptions.cacheKind != Options::AppCacheKind::kernel )