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kernel-collection-builder/KernelCacheBuilder.cpp /dev/null dyld-1340
--- /dev/null
+++ dyld/dyld-1340/kernel-collection-builder/KernelCacheBuilder.cpp
@@ -0,0 +1,186 @@
+/* -*- mode: C++; c-basic-offset: 4; indent-tabs-mode: nil -*-
+ *
+ * Copyright (c) 2014 Apple Inc. All rights reserved.
+ *
+ * @APPLE_LICENSE_HEADER_START@
+ *
+ * This file contains Original Code and/or Modifications of Original Code
+ * as defined in and that are subject to the Apple Public Source License
+ * Version 2.0 (the 'License'). You may not use this file except in
+ * compliance with the License. Please obtain a copy of the License at
+ * http://www.opensource.apple.com/apsl/ and read it before using this
+ * file.
+ *
+ * The Original Code and all software distributed under the License are
+ * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
+ * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
+ * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
+ * Please see the License for the specific language governing rights and
+ * limitations under the License.
+ *
+ * @APPLE_LICENSE_HEADER_END@
+ */
+
+#include <assert.h>
+
+#include "ASLRTracker.h"
+#include "MachOFileAbstraction.hpp"
+#include "DyldSharedCache.h"
+#include "KernelCacheBuilder.h"
+#include "Diagnostics.h"
+#include "IMPCaches.hpp"
+
+CacheBuilder::CacheBuilder(const DyldSharedCache::CreateOptions& options, const dyld3::closure::FileSystem& fileSystem)
+    : _options(options)
+    , _fileSystem(fileSystem)
+    , _fullAllocatedBuffer(0)
+    , _diagnostics(options.loggingPrefix, options.verbose)
+    , _allocatedBufferSize(0)
+{
+}
+
+CacheBuilder::~CacheBuilder() {
+}
+
+
+std::string CacheBuilder::errorMessage()
+{
+    return _diagnostics.errorMessage();
+}
+
+void CacheBuilder::copyRawSegments()
+{
+    const bool log = false;
+
+    forEachDylibInfo(^(const DylibInfo& dylib, Diagnostics& dylibDiag, cache_builder::ASLR_Tracker& dylibASLRTracker,
+                       const CacheBuilder::DylibSectionCoalescer* sectionCoalescer) {
+        for (const SegmentMappingInfo& info : dylib.cacheLocation) {
+            if (log) fprintf(stderr, "copy %s segment %15.*s (0x%08X bytes) from %p to %p (logical addr 0x%llX) for %s\n",
+                             _options.arch.name(), (int)info.segName.size(), info.segName.data(),
+                             info.copySegmentSize, info.srcSegment, info.dstSegment, info.dstCacheUnslidAddress, dylib.input->mappedFile.runtimePath.c_str());
+            ::memcpy(info.dstSegment, info.srcSegment, info.copySegmentSize);
+        }
+    });
+
+    // Copy the coalesced __TEXT sections
+    for ( const auto* coalescedSection : { &_objcCoalescedClassNames, &_objcCoalescedMethodNames, &_objcCoalescedMethodTypes } ) {
+        if ( coalescedSection->bufferSize == 0 )
+            continue;
+
+        if (log) {
+            fprintf(stderr, "copy %s __TEXT_COAL section %s (0x%08X bytes) to %p (logical addr 0x%llX)\n",
+                    _options.arch.name(), coalescedSection->sectionName.data(),
+                    coalescedSection->bufferSize, coalescedSection->bufferAddr, coalescedSection->bufferVMAddr);
+        }
+        for (const auto& stringAndOffset : coalescedSection->stringsToOffsets) {
+            ::memcpy(coalescedSection->bufferAddr + stringAndOffset.second,
+                     stringAndOffset.first.data(), stringAndOffset.first.size() + 1);
+        }
+    }
+}
+
+void CacheBuilder::adjustAllImagesForNewSegmentLocations(uint64_t cacheBaseAddress,
+                                                         LOH_Tracker* lohTracker)
+{
+    // 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,
+                       cache_builder::ASLR_Tracker& dylibASLRTracker,
+                       const CacheBuilder::DylibSectionCoalescer* sectionCoalescer) {
+        if ( dylibDiag.hasError() )
+            return;
+        adjustDylibSegments(dylib, dylibDiag, cacheBaseAddress, dylibASLRTracker,
+                            lohTracker, sectionCoalescer);
+        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::DylibSectionCoalescer ////////////////////////////////////
+
+// Returns true if the section was removed from the source dylib after being optimized
+bool CacheBuilder::DylibSectionCoalescer::sectionWasRemoved(std::string_view segmentName,
+                                                            std::string_view sectionName) const
+{
+    if ( const OptimizedSection* section = this->getSection(segmentName, sectionName) ) {
+        // Some sections, eg, GOTs, are optimized but not removed
+        if ( !section->sectionWillBeRemoved )
+            return false;
+
+        return !section->offsetMap.empty();
+    }
+
+    return false;
+}
+
+// Returns true if the section was totally removed, and hasn't been redirected to some coalesced or
+// optimized location
+bool CacheBuilder::DylibSectionCoalescer::sectionWasObliterated(std::string_view segmentName,
+                                                                std::string_view sectionName) const
+{
+    if ( const OptimizedSection* section = this->getSection(segmentName, sectionName) ) {
+        return section->sectionIsObliterated;
+    }
+
+    return false;
+}
+
+// Returns true if the section was optimized.  It may or may not have been removed too, see sectionWasRemoved().
+bool CacheBuilder::DylibSectionCoalescer::sectionWasOptimized(std::string_view segmentName,
+                                                              std::string_view sectionName) const
+{
+    if ( const OptimizedSection* section = this->getSection(segmentName, sectionName) )
+        return !section->offsetMap.empty() || section->sectionIsObliterated;
+
+    return false;
+}
+
+CacheBuilder::DylibSectionCoalescer::OptimizedSection*
+CacheBuilder::DylibSectionCoalescer::getSection(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" ) {
+        if ( sectionName == "__objc_classname" )
+            return &this->objcClassNames;
+        if ( sectionName == "__objc_methname" )
+            return &this->objcMethNames;
+        if ( sectionName == "__objc_methtype" )
+            return &this->objcMethTypes;
+    } else if ( segmentName == "__TEXT_EXEC" ) {
+        if ( sectionName == "__auth_stubs" )
+            return &this->auth_stubs;
+    } else if ( segmentName == "__DATA_CONST" ) {
+        if ( sectionName == "__got" )
+            return &this->gots;
+    } else if ( segmentName == "__AUTH_CONST" ) {
+        if ( sectionName == "__auth_got" )
+            return &this->auth_gots;
+    }
+
+    return nullptr;
+}
+
+const CacheBuilder::DylibSectionCoalescer::OptimizedSection*
+CacheBuilder::DylibSectionCoalescer::getSection(std::string_view segmentName, std::string_view sectionName) const
+{
+    return ((CacheBuilder::DylibSectionCoalescer*)this)->getSection(segmentName, sectionName);
+}
+
+void CacheBuilder::DylibSectionCoalescer::clear()
+{
+    objcClassNames.clear();
+    objcMethNames.clear();
+    objcMethTypes.clear();
+    auth_stubs.clear();
+    gots.clear();
+    auth_gots.clear();
+}