Loading...
--- dyld/dyld-750.5/dyld3/shared-cache/OptimizerObjC.cpp
+++ dyld/dyld-551.3/dyld3/shared-cache/OptimizerObjC.cpp
@@ -32,15 +32,10 @@
#include "DyldSharedCache.h"
#include "Diagnostics.h"
-#include "SharedCacheBuilder.h"
+#include "CacheBuilder.h"
#include "FileAbstraction.hpp"
#include "MachOFileAbstraction.hpp"
-#include "MachOLoaded.h"
-#include "MachOAnalyzer.h"
-
-#ifndef MH_HAS_OBJC
- #define MH_HAS_OBJC 0x40000000
-#endif
+
// Scan a C++ or Swift length-mangled field.
static bool scanMangledField(const char *&string, const char *end,
@@ -114,40 +109,37 @@
ContentAccessor(const DyldSharedCache* cache, Diagnostics& diag)
: _diagnostics(diag)
{
- _cacheStart = (uint8_t*)cache;
- _cacheUnslideAddr = cache->unslidLoadAddress();
- _slide = (uint64_t)cache - _cacheUnslideAddr;
- }
-
- // Converts from an on disk vmAddr to the real vmAddr
- // That is, for a chained fixup, decodes the chain, for a non-chained fixup, does nothing.
- uint64_t vmAddrForOnDiskVMAddr(uint64_t vmaddr) {
- return vmaddr;
+ __block int index = 0;
+ cache->forEachRegion(^(const void* content, uint64_t vmAddr, uint64_t size, uint32_t permissions) {
+ _regions[index++] = { (uint8_t*)content, (uint8_t*)content+size, vmAddr, vmAddr+size };
+ });
}
void* contentForVMAddr(uint64_t vmaddr) {
- vmaddr = vmAddrForOnDiskVMAddr(vmaddr);
- if ( vmaddr != 0 ) {
- uint64_t offset = vmaddr - _cacheUnslideAddr;
- return _cacheStart + offset;
- } else
- return nullptr;
+ for (const Info& info : _regions) {
+ if ( (info.startAddr <= vmaddr) && (vmaddr < info.endAddr) )
+ return (void*)(info.contentStart + vmaddr - info.startAddr);
+ }
+ if ( vmaddr != 0 )
+ _diagnostics.error("invalid vmaddr 0x%0llX in ObjC data", vmaddr);
+ return nullptr;
}
uint64_t vmAddrForContent(const void* content) {
- if ( content != nullptr )
- return _cacheUnslideAddr + ((uint8_t*)content - _cacheStart);
- else
- return 0;
+ for (const Info& info : _regions) {
+ if ( (info.contentStart <= content) && (content < info.contentEnd) )
+ return info.startAddr + ((uint8_t*)content - (uint8_t*)info.contentStart);
+ }
+ _diagnostics.error("invalid content pointer %p in ObjC data", content);
+ return 0;
}
Diagnostics& diagnostics() { return _diagnostics; }
private:
- Diagnostics& _diagnostics;
- uint64_t _slide;
- uint64_t _cacheUnslideAddr;
- uint8_t* _cacheStart;
+ struct Info { uint8_t* contentStart; uint8_t* contentEnd; uint64_t startAddr; uint64_t endAddr; };
+ Diagnostics& _diagnostics;
+ Info _regions[3];
};
@@ -175,10 +167,6 @@
return (pint_t)P::getP(_base[index]);
}
- pint_t getSectionVMAddress() const {
- return (pint_t)_section->addr();
- }
-
T get(pint_t index) const {
return (T)_cache->contentForVMAddr(getVMAddress(index));
}
@@ -265,18 +253,9 @@
{
_count++;
const char *s = (const char *)_cache->contentForVMAddr(oldValue);
- oldValue = (pint_t)_cache->vmAddrForOnDiskVMAddr(oldValue);
objc_opt::string_map::iterator element =
_selectorStrings.insert(objc_opt::string_map::value_type(s, oldValue)).first;
return (pint_t)element->second;
- }
-
- void visitCoalescedStrings(const CacheBuilder::CacheCoalescedText& coalescedText) {
- const CacheBuilder::CacheCoalescedText::StringSection& methodNames = coalescedText.getSectionData("__objc_methname");
- for (const auto& stringAndOffset : methodNames.stringsToOffsets) {
- uint64_t vmAddr = methodNames.bufferVMAddr + stringAndOffset.second;
- _selectorStrings[stringAndOffset.first.data()] = vmAddr;
- }
}
objc_opt::string_map& strings() {
@@ -337,13 +316,11 @@
private:
typedef typename P::uint_t pint_t;
- objc_opt::string_map _protocolNames;
- objc_opt::legacy_protocol_map _protocols;
- objc_opt::protocol_map _protocolsAndHeaders;
- size_t _protocolCount;
- size_t _protocolReferenceCount;
- Diagnostics& _diagnostics;
- HeaderInfoOptimizer<P, objc_header_info_ro_t<P>>& _hInfos;
+ objc_opt::string_map _protocolNames;
+ objc_opt::protocol_map _protocols;
+ size_t _protocolCount;
+ size_t _protocolReferenceCount;
+ Diagnostics& _diagnostics;
friend class ProtocolReferenceWalker<P, ProtocolOptimizer<P>>;
@@ -358,8 +335,8 @@
public:
- ProtocolOptimizer(Diagnostics& diag, HeaderInfoOptimizer<P, objc_header_info_ro_t<P>>& hinfos)
- : _protocolCount(0), _protocolReferenceCount(0), _diagnostics(diag), _hInfos(hinfos) {
+ ProtocolOptimizer(Diagnostics& diag)
+ : _protocolCount(0), _protocolReferenceCount(0), _diagnostics(diag) {
}
void addProtocols(ContentAccessor* cache, const macho_header<P>* header)
@@ -376,24 +353,20 @@
_diagnostics.error("objc protocol is too big");
return;
}
+
uint64_t name_vmaddr = cache->vmAddrForContent((void*)name);
uint64_t proto_vmaddr = cache->vmAddrForContent(proto);
_protocolNames.insert(objc_opt::string_map::value_type(name, name_vmaddr));
- _protocols.insert(objc_opt::legacy_protocol_map::value_type(name, proto_vmaddr));
+ _protocols.insert(objc_opt::protocol_map::value_type(name, proto_vmaddr));
_protocolCount++;
}
-
- // Note down which header this protocol came from. We'll fill in the proto_vmaddr here later
- // once we've chosen a single definition for the protocol with this name.
- uint64_t hinfo_vmaddr = cache->vmAddrForContent(_hInfos.hinfoForHeader(cache, header));
- _protocolsAndHeaders.insert(objc_opt::class_map::value_type(name, std::pair<uint64_t, uint64_t>(0, hinfo_vmaddr)));
}
}
const char *writeProtocols(ContentAccessor* cache,
uint8_t *& rwdest, size_t& rwremaining,
uint8_t *& rodest, size_t& roremaining,
- CacheBuilder::ASLR_Tracker& aslrTracker,
+ std::vector<void*>& pointersInData,
pint_t protocolClassVMAddr)
{
if (_protocolCount == 0) return NULL;
@@ -407,7 +380,9 @@
return "libobjc's read-write section is too small (metadata not optimized)";
}
- for (auto iter = _protocols.begin(); iter != _protocols.end(); ++iter)
+ for (objc_opt::protocol_map::iterator iter = _protocols.begin();
+ iter != _protocols.end();
+ ++iter)
{
objc_protocol_t<P>* oldProto = (objc_protocol_t<P>*)
cache->contentForVMAddr(iter->second);
@@ -450,19 +425,12 @@
proto->setDemangledName(cache, roName, _diagnostics);
}
proto->setFixedUp();
- proto->setIsCanonical();
// Redirect the protocol table at our new object.
iter->second = cache->vmAddrForContent(proto);
// Add new rebase entries.
- proto->addPointers(cache, aslrTracker);
- }
-
- // Now that we've chosen the canonical protocols, set the duplicate headers to
- // point to their protocols.
- for (auto iter = _protocolsAndHeaders.begin(); iter != _protocolsAndHeaders.end(); ++iter) {
- iter->second.first = _protocols[iter->first];
+ proto->addPointers(pointersInData);
}
return NULL;
@@ -474,17 +442,13 @@
refs.walk(cache, header);
}
- objc_opt::string_map& protocolNames() {
+ objc_opt::string_map& protocolNames() {
return _protocolNames;
}
- objc_opt::legacy_protocol_map& protocols() {
+ objc_opt::protocol_map& protocols() {
return _protocols;
- }
-
- objc_opt::protocol_map& protocolsAndHeaders() {
- return _protocolsAndHeaders;
- }
+ }
size_t protocolCount() const { return _protocolCount; }
size_t protocolReferenceCount() const { return _protocolReferenceCount; }
@@ -498,87 +462,9 @@
return 100;
}
+
template <typename P>
-void addObjcSegments(Diagnostics& diag, DyldSharedCache* cache, const mach_header* libobjcMH,
- uint8_t* objcReadOnlyBuffer, uint64_t objcReadOnlyBufferSizeAllocated,
- uint8_t* objcReadWriteBuffer, uint64_t objcReadWriteBufferSizeAllocated,
- uint32_t objcRwFileOffset)
-{
- // validate there is enough free space to add the load commands
- const dyld3::MachOAnalyzer* libobjcMA = ((dyld3::MachOAnalyzer*)libobjcMH);
- uint32_t freeSpace = libobjcMA->loadCommandsFreeSpace();
- const uint32_t segSize = sizeof(macho_segment_command<P>);
- if ( freeSpace < 2*segSize ) {
- diag.warning("not enough space in libojbc.dylib to add load commands for objc optimization regions");
- return;
- }
-
- // find location of LINKEDIT LC_SEGMENT load command, we need to insert new segments before it
- __block uint8_t* linkeditSeg = nullptr;
- libobjcMA->forEachSegment(^(const dyld3::MachOFile::SegmentInfo& info, bool& stop) {
- if ( strcmp(info.segName, "__LINKEDIT") == 0 )
- linkeditSeg = (uint8_t*)libobjcMH + info.loadCommandOffset;
- });
- if ( linkeditSeg == nullptr ) {
- diag.warning("__LINKEDIT not found in libojbc.dylib");
- return;
- }
-
- // move load commands to make room to insert two new ones before LINKEDIT segment load command
- uint8_t* endOfLoadCommands = (uint8_t*)libobjcMH + sizeof(macho_header<P>) + libobjcMH->sizeofcmds;
- uint32_t remainingSize = (uint32_t)(endOfLoadCommands - linkeditSeg);
- memmove(linkeditSeg+2*segSize, linkeditSeg, remainingSize);
-
- // insert new segments
- macho_segment_command<P>* roSeg = (macho_segment_command<P>*)(linkeditSeg);
- macho_segment_command<P>* rwSeg = (macho_segment_command<P>*)(linkeditSeg+sizeof(macho_segment_command<P>));
- roSeg->set_cmd(macho_segment_command<P>::CMD);
- roSeg->set_cmdsize(segSize);
- roSeg->set_segname("__OBJC_RO");
- roSeg->set_vmaddr(cache->unslidLoadAddress() + objcReadOnlyBuffer - (uint8_t*)cache);
- roSeg->set_vmsize(objcReadOnlyBufferSizeAllocated);
- roSeg->set_fileoff(objcReadOnlyBuffer - (uint8_t*)cache);
- roSeg->set_filesize(objcReadOnlyBufferSizeAllocated);
- roSeg->set_maxprot(VM_PROT_READ);
- roSeg->set_initprot(VM_PROT_READ);
- roSeg->set_nsects(0);
- roSeg->set_flags(0);
- rwSeg->set_cmd(macho_segment_command<P>::CMD);
- rwSeg->set_cmdsize(segSize);
- rwSeg->set_segname("__OBJC_RW");
- rwSeg->set_vmaddr(cache->unslidLoadAddress() + objcReadWriteBuffer - (uint8_t*)cache);
- rwSeg->set_vmsize(objcReadWriteBufferSizeAllocated);
- rwSeg->set_fileoff(objcRwFileOffset);
- rwSeg->set_filesize(objcReadWriteBufferSizeAllocated);
- rwSeg->set_maxprot(VM_PROT_WRITE|VM_PROT_READ);
- rwSeg->set_initprot(VM_PROT_WRITE|VM_PROT_READ);
- rwSeg->set_nsects(0);
- rwSeg->set_flags(0);
-
- // update mach_header to account for new load commands
- macho_header<P>* mh = (macho_header<P>*)libobjcMH;
- mh->set_sizeofcmds(mh->sizeofcmds() + 2*segSize);
- mh->set_ncmds(mh->ncmds()+2);
-
- // fix up table at start of dyld cache that has pointer into install name for libobjc
- dyld_cache_image_info* images = (dyld_cache_image_info*)((uint8_t*)cache + cache->header.imagesOffset);
- uint64_t libobjcUnslidAddress = cache->unslidLoadAddress() + ((uint8_t*)libobjcMH - (uint8_t*)cache);
- for (uint32_t i=0; i < cache->header.imagesCount; ++i) {
- if ( images[i].address == libobjcUnslidAddress ) {
- images[i].pathFileOffset += (2*segSize);
- break;
- }
- }
-}
-
-
-template <typename P>
-void doOptimizeObjC(DyldSharedCache* cache, bool forProduction, CacheBuilder::ASLR_Tracker& aslrTracker,
- CacheBuilder::LOH_Tracker& lohTracker, const CacheBuilder::CacheCoalescedText& coalescedText,
- const std::map<void*, std::string>& missingWeakImports, Diagnostics& diag,
- uint8_t* objcReadOnlyBuffer, uint64_t objcReadOnlyBufferSizeUsed, uint64_t objcReadOnlyBufferSizeAllocated,
- uint8_t* objcReadWriteBuffer, uint64_t objcReadWriteBufferSizeAllocated,
- uint32_t objcRwFileOffset)
+void optimizeObjC(DyldSharedCache* cache, bool forProduction, std::vector<void*>& pointersForASLR, Diagnostics& diag)
{
typedef typename P::E E;
typedef typename P::uint_t pint_t;
@@ -596,15 +482,15 @@
//
// Find libobjc's empty sections and build list of images with objc metadata
//
- __block const mach_header* libobjcMH = nullptr;
__block const macho_section<P> *optROSection = nullptr;
+ __block const macho_section<P> *optRWSection = nullptr;
__block const macho_section<P> *optPointerListSection = nullptr;
__block std::vector<const macho_header<P>*> objcDylibs;
cache->forEachImage(^(const mach_header* machHeader, const char* installName) {
const macho_header<P>* mh = (const macho_header<P>*)machHeader;
if ( strstr(installName, "/libobjc.") != nullptr ) {
- libobjcMH = (mach_header*)mh;
optROSection = mh->getSection("__TEXT", "__objc_opt_ro");
+ optRWSection = mh->getSection("__DATA", "__objc_opt_rw");
optPointerListSection = mh->getSection("__DATA", "__objc_opt_ptrs");
}
if ( mh->getSection("__DATA", "__objc_imageinfo") || mh->getSection("__OBJC", "__image_info") ) {
@@ -616,21 +502,23 @@
diag.warning("libobjc's read-only section missing (metadata not optimized)");
return;
}
+ if ( optRWSection == nullptr ) {
+ diag.warning("libobjc's read/write section missing (metadata not optimized)");
+ return;
+ }
if ( optPointerListSection == nullptr ) {
diag.warning("libobjc's pointer list section missing (metadata not optimized)");
return;
}
- // point optROData into space allocated in dyld cache
- uint8_t* optROData = objcReadOnlyBuffer + objcReadOnlyBufferSizeUsed;
- size_t optRORemaining = objcReadOnlyBufferSizeAllocated - objcReadOnlyBufferSizeUsed;
- *((uint32_t*)optROData) = objc_opt::VERSION;
+
+ uint8_t* optROData = (uint8_t*)cacheAccessor.contentForVMAddr(optROSection->addr());
if ( optROData == nullptr ) {
diag.warning("libobjc's read-only section has bad content");
return;
}
-
- uint8_t* optRWData = objcReadWriteBuffer;
- size_t optRWRemaining = objcReadWriteBufferSizeAllocated;
+ size_t optRORemaining = optROSection->size();
+ uint8_t* optRWData = (uint8_t*)cacheAccessor.contentForVMAddr(optRWSection->addr());
+ size_t optRWRemaining = optRWSection->size();
if (optRORemaining < headerSize) {
diag.warning("libobjc's read-only section is too small (metadata not optimized)");
return;
@@ -666,7 +554,7 @@
//
// First the RO header info
// log("writing out %d RO dylibs at offset %d", (uint32_t)objcDylibs.size(), (uint32_t)(optROSection->size() - optRORemaining));
- uint64_t hinfoROVMAddr = cacheAccessor.vmAddrForContent(optROData);
+ uint64_t hinfoROVMAddr = optROSection->addr() + optROSection->size() - optRORemaining;
HeaderInfoOptimizer<P, objc_header_info_ro_t<P>> hinfoROOptimizer;
const char* err = hinfoROOptimizer.init((uint32_t)objcDylibs.size(), optROData, optRORemaining);
if (err) {
@@ -675,13 +563,13 @@
}
else {
for (const macho_header<P>* mh : addressSortedDylibs) {
- hinfoROOptimizer.update(&cacheAccessor, mh, aslrTracker);
+ hinfoROOptimizer.update(&cacheAccessor, mh, pointersForASLR);
}
}
// Then the RW header info
// log("writing out %d RW dylibs at offset %d", (uint32_t)objcDylibs.size(), (uint32_t)(optRWSection->size() - optRWRemaining));
- uint64_t hinfoRWVMAddr = cacheAccessor.vmAddrForContent(optRWData);
+ uint64_t hinfoRWVMAddr = (uint64_t)optRWSection->addr() + (uint64_t)optRWSection->size() - optRWRemaining;
HeaderInfoOptimizer<P, objc_header_info_rw_t<P>> hinfoRWOptimizer;
err = hinfoRWOptimizer.init((uint32_t)objcDylibs.size(), optRWData, optRWRemaining);
if (err) {
@@ -690,7 +578,7 @@
}
else {
for (const macho_header<P>* mh : addressSortedDylibs) {
- hinfoRWOptimizer.update(&cacheAccessor, mh, aslrTracker);
+ hinfoRWOptimizer.update(&cacheAccessor, mh, pointersForASLR);
}
}
@@ -706,39 +594,6 @@
ObjCSelectorUniquer<P> uniq(&cacheAccessor);
std::vector<const macho_header<P>*> sizeSortedDylibs = objcDylibs;
std::sort(sizeSortedDylibs.begin(), sizeSortedDylibs.end(), [](const macho_header<P>* lmh, const macho_header<P>* rmh) -> bool {
- // Sort a select few heavy hitters first.
- auto getPriority = [](const char* installName) -> int {
- if (!strcmp(installName, "/usr/lib/libobjc.A.dylib"))
- return 0;
- if (!strcmp(installName, "/System/Library/Frameworks/Foundation.framework/Versions/C/Foundation") ||
- !strcmp(installName, "/System/Library/Frameworks/Foundation.framework/Foundation"))
- return 1;
- if (!strcmp(installName, "/System/Library/Frameworks/CoreFoundation.framework/Versions/A/CoreFoundation") ||
- !strcmp(installName, "/System/Library/Frameworks/CoreFoundation.framework/CoreFoundation"))
- return 2;
- // Note we don't sort iOSMac UIKitCore early as we want iOSMac after macOS.
- if (!strcmp(installName, "/System/Library/PrivateFrameworks/UIKitCore.framework/UIKitCore"))
- return 3;
- if (!strcmp(installName, "/System/Library/Frameworks/AppKit.framework/Versions/C/AppKit"))
- return 4;
- if (!strcmp(installName, "/System/Library/Frameworks/CFNetwork.framework/Versions/A/CFNetwork") ||
- !strcmp(installName, "/System/Library/Frameworks/CFNetwork.framework/CFNetwork"))
- return 5;
- return INT_MAX;
- };
-
- // Sort by priority first
- int priorityA = getPriority(((const dyld3::MachOFile*)lmh)->installName());
- int priorityB = getPriority(((const dyld3::MachOFile*)rmh)->installName());
- if (priorityA != priorityB)
- return priorityA < priorityB;
-
- // Sort mac before iOSMac
- bool isIOSMacA = strncmp(((const dyld3::MachOFile*)lmh)->installName(), "/System/iOSSupport/", 19) == 0;
- bool isIOSMacB = strncmp(((const dyld3::MachOFile*)rmh)->installName(), "/System/iOSSupport/", 19) == 0;
- if (isIOSMacA != isIOSMacB)
- return !isIOSMacA;
-
const macho_section<P>* lSection = lmh->getSection("__TEXT", "__objc_methname");
const macho_section<P>* rSection = rmh->getSection("__TEXT", "__objc_methname");
uint64_t lSelectorSize = (lSection ? lSection->size() : 0);
@@ -746,12 +601,7 @@
return lSelectorSize > rSelectorSize;
});
- auto alignPointer = [](uint8_t* ptr) -> uint8_t* {
- return (uint8_t*)(((uintptr_t)ptr + 0x7) & ~0x7);
- };
-
SelectorOptimizer<P, ObjCSelectorUniquer<P> > selOptimizer(uniq);
- selOptimizer.visitCoalescedStrings(coalescedText);
for (const macho_header<P>* mh : sizeSortedDylibs) {
LegacySelectorUpdater<P, ObjCSelectorUniquer<P>>::update(&cacheAccessor, mh, uniq);
selOptimizer.optimize(&cacheAccessor, mh);
@@ -760,7 +610,7 @@
diag.verbose(" uniqued %6lu selectors\n", uniq.strings().size());
diag.verbose(" updated %6lu selector references\n", uniq.count());
- uint64_t seloptVMAddr = cacheAccessor.vmAddrForContent(optROData);
+ uint64_t seloptVMAddr = optROSection->addr() + optROSection->size() - optRORemaining;
objc_opt::objc_selopt_t *selopt = new(optROData) objc_opt::objc_selopt_t;
err = selopt->write(seloptVMAddr, optRORemaining, uniq.strings());
if (err) {
@@ -768,7 +618,6 @@
return;
}
optROData += selopt->size();
- optROData = alignPointer(optROData);
optRORemaining -= selopt->size();
uint32_t seloptCapacity = selopt->capacity;
uint32_t seloptOccupied = selopt->occupied;
@@ -782,24 +631,20 @@
//
// Detect classes that have missing weak-import superclasses.
//
- // Production shared caches don't support roots so we can set this and know
- // there will definitely not be missing weak superclasses at runtime.
- // Development shared caches can set this bit as the objc runtime only trusts
- // this bit if there are no roots at runtime.
+ // Production only. Development cache does not do this: a replacement
+ // library could omit a class at runtime that was present during
+ // cache construction.
//
// This is SAFE: the binaries themselves are unmodified.
- WeakClassDetector<P> weakopt;
- bool noMissingWeakSuperclasses = weakopt.noMissingWeakSuperclasses(&cacheAccessor,
- missingWeakImports,
- sizeSortedDylibs);
-
+ bool noMissingWeakSuperclasses = false; // dev cache can't promise otherwise
if (forProduction) {
- // Shared cache does not currently support unbound weak references.
- // Here we assert that there are none. If support is added later then
+ WeakClassDetector<P> weakopt;
+ noMissingWeakSuperclasses =
+ weakopt.noMissingWeakSuperclasses(&cacheAccessor, sizeSortedDylibs);
+
+ // Shared cache does not currently support unbound weak references.
+ // Here we assert that there are none. If support is added later then
// this assertion needs to be removed and this path needs to be tested.
- // FIXME: The internal cache also isn't going to notice that an on-disk
- // dylib could resolve a weak bind from the shared cache. Should we just
- // error on all caches, regardless of dev/customer?
if (!noMissingWeakSuperclasses) {
diag.error("Some Objective-C class has a superclass that is "
"weak-import and missing from the cache.");
@@ -819,7 +664,7 @@
diag.verbose(" recorded % 6ld classes\n", classes.classNames().size());
- uint64_t clsoptVMAddr = cacheAccessor.vmAddrForContent(optROData);
+ uint64_t clsoptVMAddr = optROSection->addr() + optROSection->size() - optRORemaining;
objc_opt::objc_clsopt_t *clsopt = new(optROData) objc_opt::objc_clsopt_t;
err = clsopt->write(clsoptVMAddr, optRORemaining,
classes.classNames(), classes.classes(), false);
@@ -828,7 +673,6 @@
return;
}
optROData += clsopt->size();
- optROData = alignPointer(optROData);
optRORemaining -= clsopt->size();
size_t duplicateCount = clsopt->duplicateCount();
uint32_t clsoptCapacity = clsopt->capacity;
@@ -861,7 +705,7 @@
// This is SAFE: no protocol references are updated yet
// This must be done AFTER updating method lists.
- ProtocolOptimizer<P> protocolOptimizer(diag, hinfoROOptimizer);
+ ProtocolOptimizer<P> protocolOptimizer(diag);
for (const macho_header<P>* mh : sizeSortedDylibs) {
protocolOptimizer.addProtocols(&cacheAccessor, mh);
}
@@ -873,35 +717,30 @@
err = protocolOptimizer.writeProtocols(&cacheAccessor,
optRWData, optRWRemaining,
optROData, optRORemaining,
- aslrTracker, protocolClassVMAddr);
+ pointersForASLR, protocolClassVMAddr);
if (err) {
diag.warning("%s", err);
return;
}
- // Align the buffer again. The new protocols may have added an odd number of name characters
- optROData = alignPointer(optROData);
-
- // New protocol table which tracks loaded images.
- uint64_t protocoloptVMAddr = cacheAccessor.vmAddrForContent(optROData);
- objc_opt::objc_protocolopt2_t *protocolopt = new (optROData) objc_opt::objc_protocolopt2_t;
- err = protocolopt->write(protocoloptVMAddr, optRORemaining,
- protocolOptimizer.protocolNames(),
- protocolOptimizer.protocolsAndHeaders(), false);
+ uint64_t protocoloptVMAddr = optROSection->addr() + optROSection->size() - optRORemaining;
+ objc_opt::objc_protocolopt_t *protocolopt = new (optROData) objc_opt::objc_protocolopt_t;
+ err = protocolopt->write(protocoloptVMAddr, optRORemaining,
+ protocolOptimizer.protocolNames(),
+ protocolOptimizer.protocols(), true);
if (err) {
diag.warning("%s", err);
return;
}
optROData += protocolopt->size();
- optROData = alignPointer(optROData);
optRORemaining -= protocolopt->size();
uint32_t protocoloptCapacity = protocolopt->capacity;
uint32_t protocoloptOccupied = protocolopt->occupied;
protocolopt->byteswap(E::little_endian), protocolopt = NULL;
diag.verbose(" protocol table occupancy %u/%u (%u%%)\n",
- protocoloptOccupied, protocoloptCapacity,
- (unsigned)(protocoloptOccupied/(double)protocoloptCapacity*100));
+ protocoloptOccupied, protocoloptCapacity,
+ (unsigned)(protocoloptOccupied/(double)protocoloptCapacity*100));
// Redirect protocol references to the uniqued protocols.
@@ -949,174 +788,33 @@
}
- // Success. Update __objc_opt_ro section in libobjc.dylib to contain offsets to generated optimization structures
- objc_opt::objc_opt_t* libROHeader = (objc_opt::objc_opt_t *)cacheAccessor.contentForVMAddr(optROSection->addr());
- E::set32(libROHeader->flags, headerFlags);
- E::set32(libROHeader->selopt_offset, (uint32_t)(seloptVMAddr - optROSection->addr()));
- E::set32(libROHeader->clsopt_offset, (uint32_t)(clsoptVMAddr - optROSection->addr()));
- E::set32(libROHeader->unused_protocolopt_offset, 0);
- E::set32(libROHeader->headeropt_ro_offset, (uint32_t)(hinfoROVMAddr - optROSection->addr()));
- E::set32(libROHeader->headeropt_rw_offset, (uint32_t)(hinfoRWVMAddr - optROSection->addr()));
- E::set32(libROHeader->protocolopt_offset, (uint32_t)(protocoloptVMAddr - optROSection->addr()));
+ // Success. Update RO header last.
+ E::set32(optROHeader->flags, headerFlags);
+ E::set32(optROHeader->selopt_offset, (uint32_t)(seloptVMAddr - optROSection->addr()));
+ E::set32(optROHeader->clsopt_offset, (uint32_t)(clsoptVMAddr - optROSection->addr()));
+ E::set32(optROHeader->protocolopt_offset, (uint32_t)(protocoloptVMAddr - optROSection->addr()));
+ E::set32(optROHeader->headeropt_ro_offset, (uint32_t)(hinfoROVMAddr - optROSection->addr()));
+ E::set32(optROHeader->headeropt_rw_offset, (uint32_t)(hinfoRWVMAddr - optROSection->addr()));
// Log statistics.
- size_t roSize = objcReadOnlyBufferSizeAllocated - optRORemaining;
- size_t rwSize = objcReadWriteBufferSizeAllocated - optRWRemaining;
- diag.verbose(" %lu/%llu bytes (%d%%) used in shared cache read-only optimization region\n",
- roSize, objcReadOnlyBufferSizeAllocated, percent(roSize, objcReadOnlyBufferSizeAllocated));
- diag.verbose(" %lu/%llu bytes (%d%%) used in shared cache read/write optimization region\n",
- rwSize, objcReadWriteBufferSizeAllocated, percent(rwSize, objcReadWriteBufferSizeAllocated));
+ size_t roSize = optROSection->size() - optRORemaining;
+ size_t rwSize = optRWSection->size() - optRWRemaining;
+ diag.verbose(" %lu/%llu bytes (%d%%) used in libobjc read-only optimization section\n",
+ roSize, optROSection->size(), percent(roSize, optROSection->size()));
+ diag.verbose(" %lu/%llu bytes (%d%%) used in libobjc read/write optimization section\n",
+ rwSize, optRWSection->size(), percent(rwSize, optRWSection->size()));
diag.verbose(" wrote objc metadata optimization version %d\n", objc_opt::VERSION);
-
- // Add segments to libobjc.dylib that cover cache builder allocated r/o and r/w regions
- addObjcSegments<P>(diag, cache, libobjcMH, objcReadOnlyBuffer, objcReadOnlyBufferSizeAllocated, objcReadWriteBuffer, objcReadWriteBufferSizeAllocated, objcRwFileOffset);
-
-
- // Now that objc has uniqued the selector references, we can apply the LOHs so that ADRP/LDR -> ADRP/ADD
- if (forProduction) {
- const bool logSelectors = false;
- uint64_t lohADRPCount = 0;
- uint64_t lohLDRCount = 0;
-
- for (auto& targetAndInstructions : lohTracker) {
- uint64_t targetVMAddr = targetAndInstructions.first;
- if (!selOptimizer.isSelectorRefAddress((pint_t)targetVMAddr))
- continue;
-
- std::set<void*>& instructions = targetAndInstructions.second;
- // We do 2 passes over the instructions. The first to validate them and the second
- // to actually update them.
- for (unsigned pass = 0; pass != 2; ++pass) {
- uint32_t adrpCount = 0;
- uint32_t ldrCount = 0;
- for (void* instructionAddress : instructions) {
- uint32_t& instruction = *(uint32_t*)instructionAddress;
- uint64_t instructionVMAddr = cacheAccessor.vmAddrForContent(&instruction);
- uint64_t selRefContent = *(uint64_t*)cacheAccessor.contentForVMAddr(targetVMAddr);
- const char* selectorString = (const char*)cacheAccessor.contentForVMAddr(selRefContent);
- uint64_t selectorStringVMAddr = cacheAccessor.vmAddrForContent(selectorString);
-
- if ( (instruction & 0x9F000000) == 0x90000000 ) {
- // ADRP
- int64_t pageDistance = ((selectorStringVMAddr & ~0xFFF) - (instructionVMAddr & ~0xFFF));
- int64_t newPage21 = pageDistance >> 12;
-
- if (pass == 0) {
- if ( (newPage21 > 2097151) || (newPage21 < -2097151) ) {
- if (logSelectors)
- fprintf(stderr, "Out of bounds ADRP selector reference target\n");
- instructions.clear();
- break;
- }
- ++adrpCount;
- }
-
- if (pass == 1) {
- instruction = (instruction & 0x9F00001F) | ((newPage21 << 29) & 0x60000000) | ((newPage21 << 3) & 0x00FFFFE0);
- ++lohADRPCount;
- }
- continue;
- }
-
- if ( (instruction & 0x3B000000) == 0x39000000 ) {
- // LDR/STR. STR shouldn't be possible as this is a selref!
- if (pass == 0) {
- if ( (instruction & 0xC0C00000) != 0xC0400000 ) {
- // Not a load, or dest reg isn't xN, or uses sign extension
- if (logSelectors)
- fprintf(stderr, "Bad LDR for selector reference optimisation\n");
- instructions.clear();
- break;
- }
- if ( (instruction & 0x04000000) != 0 ) {
- // Loading a float
- if (logSelectors)
- fprintf(stderr, "Bad LDR for selector reference optimisation\n");
- instructions.clear();
- break;
- }
- ++ldrCount;
- }
-
- if (pass == 1) {
- uint32_t ldrDestReg = (instruction & 0x1F);
- uint32_t ldrBaseReg = ((instruction >> 5) & 0x1F);
-
- // Convert the LDR to an ADD
- instruction = 0x91000000;
- instruction |= ldrDestReg;
- instruction |= ldrBaseReg << 5;
- instruction |= (selectorStringVMAddr & 0xFFF) << 10;
-
- ++lohLDRCount;
- }
- continue;
- }
-
- if ( (instruction & 0xFFC00000) == 0x91000000 ) {
- // ADD imm12
- // We don't support ADDs.
- if (logSelectors)
- fprintf(stderr, "Bad ADD for selector reference optimisation\n");
- instructions.clear();
- break;
- }
-
- if (logSelectors)
- fprintf(stderr, "Unknown instruction for selref optimisation\n");
- instructions.clear();
- break;
- }
- if (pass == 0) {
- // If we didn't see at least one ADRP/LDR in pass one then don't optimize this location
- if ((adrpCount == 0) || (ldrCount == 0)) {
- instructions.clear();
- break;
- }
- }
- }
- }
-
- diag.verbose(" Optimized %lld ADRP LOHs\n", lohADRPCount);
- diag.verbose(" Optimized %lld LDR LOHs\n", lohLDRCount);
- }
}
} // anon namespace
-void SharedCacheBuilder::optimizeObjC()
+void optimizeObjC(DyldSharedCache* cache, bool is64, bool customerCache, std::vector<void*>& pointersForASLR, Diagnostics& diag)
{
- uint32_t objcRwFileOffset = (uint32_t)((_objcReadWriteBuffer - _readWriteRegion.buffer) + _readWriteRegion.cacheFileOffset);
- if ( _archLayout->is64 )
- doOptimizeObjC<Pointer64<LittleEndian>>((DyldSharedCache*)_readExecuteRegion.buffer, _options.optimizeStubs, _aslrTracker, _lohTracker,
- _coalescedText, _missingWeakImports,
- _diagnostics, _objcReadOnlyBuffer, _objcReadOnlyBufferSizeUsed, _objcReadOnlyBufferSizeAllocated,
- _objcReadWriteBuffer, _objcReadWriteBufferSizeAllocated, objcRwFileOffset);
+ if ( is64 )
+ optimizeObjC<Pointer64<LittleEndian>>(cache, customerCache, pointersForASLR, diag);
else
- doOptimizeObjC<Pointer32<LittleEndian>>((DyldSharedCache*)_readExecuteRegion.buffer, _options.optimizeStubs, _aslrTracker, _lohTracker,
- _coalescedText, _missingWeakImports,
- _diagnostics, _objcReadOnlyBuffer, _objcReadOnlyBufferSizeUsed, _objcReadOnlyBufferSizeAllocated,
- _objcReadWriteBuffer, _objcReadWriteBufferSizeAllocated, objcRwFileOffset);
+ optimizeObjC<Pointer32<LittleEndian>>(cache, customerCache, pointersForASLR, diag);
}
-static uint32_t hashTableSize(uint32_t maxElements, uint32_t perElementData)
-{
- uint32_t elementsWithPadding = maxElements*11/10; // if close to power of 2, perfect hash may fail, so don't get within 10% of that
- uint32_t powTwoCapacity = 1 << (32 - __builtin_clz(elementsWithPadding - 1));
- uint32_t headerSize = 4*(8+256);
- return headerSize + powTwoCapacity/2 + powTwoCapacity + powTwoCapacity*perElementData;
-}
-
-// The goal here is to allocate space in the dyld shared cache (while it is being laid out) that will contain
-// the objc structures that previously were in the __objc_opt_ro section.
-uint32_t SharedCacheBuilder::computeReadOnlyObjC(uint32_t selRefCount, uint32_t classDefCount, uint32_t protocolDefCount)
-{
- return 0xA000 + hashTableSize(selRefCount, 5) + hashTableSize(classDefCount, 12) + hashTableSize(protocolDefCount, 8);
-}
-
-// Space to replace the __objc_opt_rw section.
-uint32_t SharedCacheBuilder::computeReadWriteObjC(uint32_t imageCount, uint32_t protocolDefCount)
-{
- return 8*imageCount + protocolDefCount*12*(_archLayout->is64 ? 8 : 4);
-}
+