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src/ImageLoaderMachO.cpp dyld-851.27 dyld-421.2
--- dyld/dyld-851.27/src/ImageLoaderMachO.cpp
+++ dyld/dyld-421.2/src/ImageLoaderMachO.cpp
@@ -39,7 +39,6 @@
 #include <mach/thread_status.h>
 #include <mach-o/loader.h> 
 #include <mach-o/nlist.h> 
-#include <mach-o/dyld_images.h>
 #include <sys/sysctl.h>
 #include <sys/syscall.h>
 #include <libkern/OSAtomic.h>
@@ -47,26 +46,34 @@
 #include <stdint.h>
 #include <System/sys/codesign.h>
 
-#if __has_feature(ptrauth_calls)
-#include <ptrauth.h>
-#endif
-
 #include "ImageLoaderMachO.h"
 #include "ImageLoaderMachOCompressed.h"
 #if SUPPORT_CLASSIC_MACHO
 #include "ImageLoaderMachOClassic.h"
 #endif
-#include "Tracing.h"
-#include "dyld2.h"
+#include "mach-o/dyld_images.h"
+#include "dyld.h"
 
 // <rdar://problem/8718137> use stack guard random value to add padding between dylibs
 extern "C" long __stack_chk_guard;
 
-#define LIBSYSTEM_DYLIB_PATH 		  	  "/usr/lib/libSystem.B.dylib"
-#define LIBDYLD_DYLIB_PATH 		  	  "/usr/lib/system/libdyld.dylib"
-#if TARGET_OS_OSX
-  #define DRIVERKIT_LIBSYSTEM_DYLIB_PATH  "/System/DriverKit/usr/lib/libSystem.dylib"
-  #define DRIVERKIT_LIBDYLD_DYLIB_PATH 	  "/System/DriverKit/usr/lib/system/libdyld.dylib"
+#ifndef LC_LOAD_UPWARD_DYLIB
+	#define	LC_LOAD_UPWARD_DYLIB (0x23|LC_REQ_DYLD)	/* load of dylib whose initializers run later */
+#endif
+
+#ifndef LC_VERSION_MIN_TVOS
+	#define LC_VERSION_MIN_TVOS 0x2F
+#endif
+
+#ifndef LC_VERSION_MIN_WATCHOS
+	#define LC_VERSION_MIN_WATCHOS 0x30
+#endif
+
+
+#if TARGET_IPHONE_SIMULATOR
+	#define LIBSYSTEM_DYLIB_PATH "/usr/lib/libSystem.dylib"
+#else
+	#define LIBSYSTEM_DYLIB_PATH "/usr/lib/libSystem.B.dylib"
 #endif
 
 // relocation_info.r_length field has value 3 for 64-bit executables and value 2 for 32-bit executables
@@ -97,14 +104,12 @@
 #if TEXT_RELOC_SUPPORT
 	fTextSegmentRebases(false),
 	fTextSegmentBinds(false),
-#else
-    fReadOnlyDataSegment(false),
 #endif
 #if __i386__
 	fReadOnlyImportSegment(false),
 #endif
 	fHasSubLibraries(false), fHasSubUmbrella(false), fInUmbrella(false), fHasDOFSections(false), fHasDashInit(false),
-	fHasInitializers(false), fHasTerminators(false), fNotifyObjC(false), fRetainForObjC(false), fRegisteredAsRequiresCoalescing(false), fOverrideOfCacheImageNum(0)
+	fHasInitializers(false), fHasTerminators(false), fNotifyObjC(false), fRetainForObjC(false), fRegisteredAsRequiresCoalescing(false)
 {
 	fIsSplitSeg = ((mh->flags & MH_SPLIT_SEGS) != 0);        
 
@@ -127,7 +132,7 @@
 
 }
 
-#if TARGET_OS_OSX
+#if __MAC_OS_X_VERSION_MIN_REQUIRED
 static uintptr_t pageAlign(uintptr_t value)
 {
 	return (value + 4095) & (-4096);
@@ -148,6 +153,8 @@
 
 	const uint32_t cmd_count = mh->ncmds;
 	const uint32_t sizeofcmds = mh->sizeofcmds;
+	if ( sizeofcmds > (MAX_MACH_O_HEADER_AND_LOAD_COMMANDS_SIZE-sizeof(macho_header)) )
+		dyld::throwf("malformed mach-o: load commands size (%u) > %u", sizeofcmds, MAX_MACH_O_HEADER_AND_LOAD_COMMANDS_SIZE);
 	if ( cmd_count > (sizeofcmds/sizeof(load_command)) )
 		dyld::throwf("malformed mach-o: ncmds (%u) too large to fit in sizeofcmds (%u)", cmd_count, sizeofcmds);
 	const struct load_command* const startCmds = (struct load_command*)(((uint8_t*)mh) + sizeof(macho_header));
@@ -157,8 +164,6 @@
 	const macho_segment_command* linkeditSegCmd = NULL;
 	const macho_segment_command* startOfFileSegCmd = NULL;
 	const dyld_info_command* dyldInfoCmd = NULL;
-	const linkedit_data_command* chainedFixupsCmd = NULL;
-	const linkedit_data_command* exportsTrieCmd = NULL;
 	const symtab_command* symTabCmd = NULL;
 	const dysymtab_command*	dynSymbTabCmd = NULL;
 	for (uint32_t i = 0; i < cmd_count; ++i) {
@@ -182,20 +187,9 @@
 				dyldInfoCmd = (struct dyld_info_command*)cmd;
 				*compressed = true;
 				break;
-			case LC_DYLD_CHAINED_FIXUPS:
-				if ( cmd->cmdsize != sizeof(linkedit_data_command) )
-					throw "malformed mach-o image: LC_DYLD_CHAINED_FIXUPS size wrong";
-				chainedFixupsCmd = (struct linkedit_data_command*)cmd;
-				*compressed = true;
-				break;
-			case LC_DYLD_EXPORTS_TRIE:
-				if ( cmd->cmdsize != sizeof(linkedit_data_command) )
-					throw "malformed mach-o image: LC_DYLD_EXPORTS_TRIE size wrong";
-				exportsTrieCmd = (struct linkedit_data_command*)cmd;
-				break;
 			case LC_SEGMENT_COMMAND:
 				segCmd = (struct macho_segment_command*)cmd;
-#if TARGET_OS_OSX
+#if __MAC_OS_X_VERSION_MIN_REQUIRED
 				// rdar://problem/19617624 allow unmapped segments on OSX (but not iOS)
 				if ( ((segCmd->filesize) > pageAlign(segCmd->vmsize)) && (segCmd->vmsize != 0) )
 #else
@@ -211,7 +205,7 @@
 				if ( segCmd->vmsize != 0 )
 					*segCount += 1;
 				if ( strcmp(segCmd->segname, "__LINKEDIT") == 0 ) {
-		#if TARGET_OS_SIMULATOR
+		#if TARGET_IPHONE_SIMULATOR
 					// Note: should check on all platforms that __LINKEDIT is read-only, but <rdar://problem/22637626&22525618>
 					if ( segCmd->initprot != VM_PROT_READ )
 						throw "malformed mach-o image: __LINKEDIT segment does not have read-only permissions";
@@ -230,7 +224,7 @@
 					if ( (segCmd->initprot != 0) && ((segCmd->initprot & VM_PROT_READ) == 0) )
 						dyld::throwf("malformed mach-o image: %s segment is not mapped readable", segCmd->segname);
 				}
-                if ( (segCmd->fileoff == 0) && (segCmd->filesize != 0) ) {
+				if ( (segCmd->fileoff == 0) && (segCmd->filesize != 0) ) {
 					if ( (segCmd->initprot & VM_PROT_READ) == 0 )
 						dyld::throwf("malformed mach-o image: %s segment maps start of file but is not readable", segCmd->segname);
 					if ( (segCmd->initprot & VM_PROT_WRITE) == VM_PROT_WRITE ) {
@@ -305,7 +299,6 @@
 			case LC_LOAD_UPWARD_DYLIB:
 				*libCount += 1;
 				// fall thru
-				[[clang::fallthrough]];
 			case LC_ID_DYLIB:
 				dylibCmd = (dylib_command*)cmd;
 				if ( dylibCmd->dylib.name.offset > cmdLength )
@@ -347,13 +340,12 @@
 					throw "malformed mach-o image: LC_DYSYMTAB size wrong";
 				dynSymbTabCmd = (dysymtab_command*)cmd;
 				break;
-#if TARGET_OS_OSX
+#if __MAC_OS_X_VERSION_MIN_REQUIRED
 			// <rdar://problem/26797345> error when loading iOS Simulator mach-o binary into macOS process
 			case LC_VERSION_MIN_WATCHOS:
 			case LC_VERSION_MIN_TVOS:
 			case LC_VERSION_MIN_IPHONEOS:
-				if ( !context.iOSonMac )
-					throw "mach-o, but built for simulator (not macOS)";
+				throw "mach-o, but built for simulator (not macOS)";
 				break;
 #endif
 		}
@@ -364,10 +356,10 @@
 		throw "load commands not in a segment";
 	if ( linkeditSegCmd == NULL )
 		throw "malformed mach-o image: missing __LINKEDIT segment";
-	if ( !inCache && (startOfFileSegCmd == NULL) )
+	if ( startOfFileSegCmd == NULL )
 		throw "malformed mach-o image: missing __TEXT segment that maps start of file";
 	// <rdar://problem/13145644> verify every segment does not overlap another segment
-	if ( context.strictMachORequired && !inCache ) {
+	if ( context.strictMachORequired ) {
 		uintptr_t lastFileStart = 0;
 		uintptr_t linkeditFileStart = 0;
 		const struct load_command* cmd1 = startCmds;
@@ -414,8 +406,8 @@
 	}
 
 	// validate linkedit content
-	if  ( (dyldInfoCmd == NULL) && (chainedFixupsCmd == NULL) && (symTabCmd == NULL) )
-		throw "malformed mach-o image: missing LC_SYMTAB, LC_DYLD_INFO, or LC_DYLD_CHAINED_FIXUPS";
+	if  ( (dyldInfoCmd == NULL) && (symTabCmd == NULL) )
+		throw "malformed mach-o image: missing LC_SYMTAB or LC_DYLD_INFO";
 	if  ( dynSymbTabCmd == NULL )
 		throw "malformed mach-o image: missing LC_DYSYMTAB";
 
@@ -472,25 +464,9 @@
 		}
 	}
 
-	if ( !inCache && (chainedFixupsCmd != NULL) && context.strictMachORequired ) {
-		// validate all LC_DYLD_CHAINED_FIXUPS chunks fit in LINKEDIT and don't overlap
-		if ( chainedFixupsCmd->dataoff < linkeditFileOffsetStart )
-			throw "malformed mach-o image: dyld chained fixups info underruns __LINKEDIT";
-		if ( (chainedFixupsCmd->dataoff + chainedFixupsCmd->datasize) > linkeditFileOffsetEnd )
-			throw "malformed mach-o image: dyld chained fixups info overruns __LINKEDIT";
-	}
-
-	if ( !inCache && (exportsTrieCmd != NULL) && context.strictMachORequired ) {
-		// validate all LC_DYLD_EXPORTS_TRIE chunks fit in LINKEDIT and don't overlap
-		if ( exportsTrieCmd->dataoff < linkeditFileOffsetStart )
-			throw "malformed mach-o image: dyld chained fixups info underruns __LINKEDIT";
-		if ( (exportsTrieCmd->dataoff + exportsTrieCmd->datasize) > linkeditFileOffsetEnd )
-			throw "malformed mach-o image: dyld chained fixups info overruns __LINKEDIT";
-	}
-
 	if ( symTabCmd != NULL ) {
 		// validate symbol table fits in LINKEDIT
-		if ( (symTabCmd->nsyms > 0) && (symTabCmd->symoff < linkeditFileOffsetStart) )
+		if ( symTabCmd->symoff < linkeditFileOffsetStart )
 			throw "malformed mach-o image: symbol table underruns __LINKEDIT";
 		if ( symTabCmd->nsyms > 0x10000000 )
 			throw "malformed mach-o image: symbol table too large";
@@ -508,13 +484,6 @@
 			if ( context.strictMachORequired || (symTabCmd->stroff + symTabCmd->strsize > ((linkeditFileOffsetEnd + 4095) & (-4096))) )
 				throw "malformed mach-o image: symbol strings overrun __LINKEDIT";
 		}
-#if TARGET_OS_OSX
-		if ( (symTabCmd->symoff % sizeof(void*)) != 0 ) {
-			// <rdar://53723577> allow old malformed plugins in new app
-			if ( sdkVersion((mach_header*)mh) >= DYLD_PACKED_VERSION(10,15,0) )
-				throw "malformed mach-o image: mis-aligned symbol table __LINKEDIT";
-		}
-#endif
 		// validate indirect symbol table
 		if ( dynSymbTabCmd->nindirectsyms != 0 ) {
 			if ( dynSymbTabCmd->indirectsymoff < linkeditFileOffsetStart )
@@ -554,10 +523,6 @@
 
 	if ( needsAddedLibSystemDepency(*libCount, mh) )
 		*libCount = 1;
-
-	// dylibs that use LC_DYLD_CHAINED_FIXUPS have that load command removed when put in the dyld cache
-	if ( !*compressed && (mh->flags & MH_DYLIB_IN_CACHE) )
-		*compressed = true;
 }
 
 
@@ -670,11 +635,8 @@
 	for(unsigned int i=0; i < fSegmentsCount; ++i) {
 		// set up pointer to __LINKEDIT segment
 		if ( strcmp(segName(i),"__LINKEDIT") == 0 ) {
-	#if !TARGET_OS_OSX
-			// <rdar://problem/42419336> historically, macOS never did this check
-			if ( segFileOffset(i) > fCoveredCodeLength )
+			if ( context.requireCodeSignature && (segFileOffset(i) > fCoveredCodeLength))
 				dyld::throwf("cannot load '%s' (segment outside of code signature)", this->getShortName());
-	#endif
 			fLinkEditBase = (uint8_t*)(segActualLoadAddress(i) - segFileOffset(i));
 		}
 #if TEXT_RELOC_SUPPORT
@@ -685,9 +647,6 @@
 			if ( segHasBindFixUps(i) )
 				fTextSegmentBinds = true;
 		}
-#else
-		if ( segIsReadOnlyData(i) )
-			fReadOnlyDataSegment = true;
 #endif
 #if __i386__
 		if ( segIsReadOnlyImport(i) )
@@ -713,8 +672,6 @@
 
 	// walk load commands (mapped in at start of __TEXT segment)
 	const dyld_info_command* dyldInfo = NULL;
-	const linkedit_data_command* chainedFixupsCmd = NULL;
-	const linkedit_data_command* exportsTrieCmd = NULL;
 	const macho_nlist* symbolTable = NULL;
 	const char* symbolTableStrings = NULL;
 	const struct load_command* firstUnknownCmd = NULL;
@@ -751,17 +708,11 @@
 			case LC_DYLD_INFO_ONLY:
 				dyldInfo = (struct dyld_info_command*)cmd;
 				break;
-			case LC_DYLD_CHAINED_FIXUPS:
-				chainedFixupsCmd = (struct linkedit_data_command*)cmd;
-				break;
-			case LC_DYLD_EXPORTS_TRIE:
-				exportsTrieCmd = (struct linkedit_data_command*)cmd;
-				break;
 			case LC_SEGMENT_COMMAND:
 				{
 					const struct macho_segment_command* seg = (struct macho_segment_command*)cmd;
 					const bool isTextSeg = (strcmp(seg->segname, "__TEXT") == 0);
-		#if __i386__ && TARGET_OS_OSX
+		#if __i386__ && __MAC_OS_X_VERSION_MIN_REQUIRED
 					const bool isObjCSeg = (strcmp(seg->segname, "__OBJC") == 0);
 					if ( isObjCSeg )
 						fNotifyObjC = true;
@@ -774,8 +725,6 @@
 						const uint8_t type = sect->flags & SECTION_TYPE;
 						if ( type == S_MOD_INIT_FUNC_POINTERS )
 							fHasInitializers = true;
-						else if ( type == S_INIT_FUNC_OFFSETS )
-							fHasInitializers = true;
 						else if ( type == S_MOD_TERM_FUNC_POINTERS )
 							fHasTerminators = true;
 						else if ( type == S_DTRACE_DOF )
@@ -785,7 +734,7 @@
 						else if ( isTextSeg && (strcmp(sect->sectname, "__unwind_info") == 0) )
 							fUnwindInfoSectionOffset = (uint32_t)((uint8_t*)sect - fMachOData);
 
-		#if __i386__ && TARGET_OS_OSX
+		#if __i386__ && __MAC_OS_X_VERSION_MIN_REQUIRED
 						else if ( isObjCSeg ) {
 							if ( strcmp(sect->sectname, "__image_info") == 0 ) {
 								const uint32_t* imageInfo = (uint32_t*)(sect->addr + fSlide);
@@ -799,7 +748,7 @@
 						}
 		#else
 						else if ( isDataSeg && (strncmp(sect->sectname, "__objc_imageinfo", 16) == 0) ) {
-			#if TARGET_OS_OSX
+			#if __MAC_OS_X_VERSION_MIN_REQUIRED
 							const uint32_t* imageInfo = (uint32_t*)(sect->addr + fSlide);
 							uint32_t flags = imageInfo[1];
 							if ( (flags & 4) && (((macho_header*)fMachOData)->filetype != MH_EXECUTE) )
@@ -826,6 +775,7 @@
 		    case LC_REEXPORT_DYLIB:
 			case LC_LOAD_UPWARD_DYLIB:
 			case LC_MAIN:
+				// do nothing, just prevent LC_REQ_DYLD exception from occuring
 				break;
 			case LC_VERSION_MIN_MACOSX:
 			case LC_VERSION_MIN_IPHONEOS:
@@ -857,13 +807,9 @@
 	
 	if ( dyldInfo != NULL )
 		this->setDyldInfo(dyldInfo);
-	if ( chainedFixupsCmd != NULL )
-		this->setChainedFixups(chainedFixupsCmd);
-	if ( exportsTrieCmd != NULL )
-		this->setExportsTrie(exportsTrieCmd);
-
 	if ( symbolTable != NULL)
 		this->setSymbolTableInfo(symbolTable, symbolTableStrings, dynSymbolTable);
+	
 }
 
 // don't do this work in destructor because we need object to be full subclass
@@ -1013,13 +959,6 @@
 }
 #endif
 
-bool ImageLoaderMachO::segIsReadOnlyData(unsigned int segIndex) const
-{
-	const macho_segment_command* segCmd = segLoadCommand(segIndex);
-	return (    (segCmd->initprot & VM_PROT_WRITE)
-			&& ((segCmd->initprot & VM_PROT_EXECUTE) == 0)
-			&& (segCmd->flags & SG_READ_ONLY) );
-}
 
 void ImageLoaderMachO::UnmapSegments()
 {
@@ -1047,6 +986,32 @@
 }
 
 
+// prefetch __DATA/__OBJC pages during launch, but not for dynamically loaded code
+void ImageLoaderMachO::preFetchDATA(int fd, uint64_t offsetInFat, const LinkContext& context)
+{
+	if ( context.linkingMainExecutable ) {
+		for(unsigned int i=0, e=segmentCount(); i < e; ++i) {
+			if ( segWriteable(i) && (segFileSize(i) > 0) ) {
+				// prefetch writable segment that have mmap'ed regions
+				radvisory advice;
+				advice.ra_offset = offsetInFat + segFileOffset(i);
+				advice.ra_count = (int)segFileSize(i);
+				// limit prefetch to 1MB (256 pages)
+				if ( advice.ra_count > 1024*1024 )
+					advice.ra_count = 1024*1024;
+				// don't prefetch single pages, let them fault in
+				fgTotalBytesPreFetched += advice.ra_count;
+				fcntl(fd, F_RDADVISE, &advice);
+				if ( context.verboseMapping ) {
+					dyld::log("%18s prefetching 0x%0lX -> 0x%0lX\n", 
+						segName(i), segActualLoadAddress(i), segActualLoadAddress(i)+advice.ra_count-1);
+				}
+			}
+		}
+	}
+}
+
+
 bool ImageLoaderMachO::segmentsMustSlideTogether() const 
 {
 	return true;
@@ -1131,27 +1096,29 @@
 
 void ImageLoaderMachO::loadCodeSignature(const struct linkedit_data_command* codeSigCmd, int fd,  uint64_t offsetInFatFile, const LinkContext& context)
 {
-	dyld3::ScopedTimer(DBG_DYLD_TIMING_ATTACH_CODESIGNATURE, 0, 0, 0);
 	// if dylib being loaded has no code signature load command
 	if ( codeSigCmd == NULL) {
-		disableCoverageCheck();
+		if (context.requireCodeSignature ) {
+			// if we require dylibs to be codesigned there needs to be a signature.
+			dyld::throwf("required code signature missing for '%s'\n", this->getPath());
+		} else {
+			disableCoverageCheck();
+		}
 	}
 	else {
-#if TARGET_OS_OSX
+#if __MAC_OS_X_VERSION_MIN_REQUIRED
 		// <rdar://problem/13622786> ignore code signatures in binaries built with pre-10.9 tools
-		if ( this->sdkVersion() < DYLD_PACKED_VERSION(10,9,0) ) {
-			disableCoverageCheck();
+		if ( this->sdkVersion() < DYLD_MACOSX_VERSION_10_9 ) {
 			return;
 		}
 #endif
-
 		fsignatures_t siginfo;
-		siginfo.fs_file_start=offsetInFatFile;				// start of mach-o slice in fat file
+		siginfo.fs_file_start=offsetInFatFile;				// start of mach-o slice in fat file 
 		siginfo.fs_blob_start=(void*)(long)(codeSigCmd->dataoff);	// start of CD in mach-o file
 		siginfo.fs_blob_size=codeSigCmd->datasize;			// size of CD
 		int result = fcntl(fd, F_ADDFILESIGS_RETURN, &siginfo);
 
-#if TARGET_OS_SIMULATOR
+#if TARGET_IPHONE_SIMULATOR
 		// rdar://problem/18759224> check range covered by the code directory after loading
 		// Attempt to fallback only if we are in the simulator
 
@@ -1164,50 +1131,60 @@
 		if ( result == -1 ) {
 			if ( (errno == EPERM) || (errno == EBADEXEC) )
 				dyld::throwf("code signature invalid for '%s'\n", this->getPath());
-			if ( context.verboseCodeSignatures )
+			if ( context.verboseCodeSignatures ) 
 				dyld::log("dyld: Failed registering code signature for %s, errno=%d\n", this->getPath(), errno);
 			siginfo.fs_file_start = UINT64_MAX;
 		} else if ( context.verboseCodeSignatures )  {
 			dyld::log("dyld: Registered code signature for %s\n", this->getPath());
 		}
 		fCoveredCodeLength = siginfo.fs_file_start;
-	}
-
-	{
-		fchecklv checkInfo;
-		char  messageBuffer[512];
-		messageBuffer[0] = '\0';
-		checkInfo.lv_file_start = offsetInFatFile;
-		checkInfo.lv_error_message_size = sizeof(messageBuffer);
-		checkInfo.lv_error_message = messageBuffer;
-		int res = fcntl(fd, F_CHECK_LV, &checkInfo);
-		if ( res == -1 ) {
-			dyld::throwf("code signature in (%s) not valid for use in process using Library Validation: %s", this->getPath(), messageBuffer);
-		}
+
+#if __MAC_OS_X_VERSION_MIN_REQUIRED
+		if ( context.processUsingLibraryValidation ) {
+			fchecklv checkInfo;
+			char  messageBuffer[512];
+			messageBuffer[0] = '\0';
+			checkInfo.lv_file_start = offsetInFatFile;
+			checkInfo.lv_error_message_size = sizeof(messageBuffer);
+			checkInfo.lv_error_message = messageBuffer;
+			int res = fcntl(fd, F_CHECK_LV, &checkInfo);
+			if ( res == -1 ) {
+				dyld::throwf("code signature in (%s) not valid for use in process using Library Validation: %s", this->getPath(), messageBuffer);
+			}
+		}
+#endif
 	}
 }
 
 void ImageLoaderMachO::validateFirstPages(const struct linkedit_data_command* codeSigCmd, int fd, const uint8_t *fileData, size_t lenFileData, off_t offsetInFat, const LinkContext& context)
 {
-#if TARGET_OS_OSX
+#if __MAC_OS_X_VERSION_MIN_REQUIRED
 	// rdar://problem/21839703> 15A226d: dyld crashes in mageLoaderMachO::validateFirstPages during dlopen() after encountering an mmap failure
 	// We need to ignore older code signatures because they will be bad.
-	if ( this->sdkVersion() < DYLD_PACKED_VERSION(10,9,0) ) {
+	if ( this->sdkVersion() < DYLD_MACOSX_VERSION_10_9 ) {
 		return;
 	}
 #endif
 	if (codeSigCmd != NULL) {
-		void *fdata = xmmap(NULL, lenFileData, PROT_READ, MAP_SHARED, fd, offsetInFat);
+		void *fdata = xmmap(NULL, lenFileData, PROT_READ | PROT_EXEC, MAP_SHARED, fd, offsetInFat);
 		if ( fdata == MAP_FAILED ) {
-			int errnoCopy = errno;
-			if ( errnoCopy == EPERM ) {
-				if ( dyld::sandboxBlockedMmap(getPath()) )
-					dyld::throwf("file system sandbox blocked mmap() of '%s'", getPath());
-				else
-					dyld::throwf("code signing blocked mmap() of '%s'", getPath());
+#if __MAC_OS_X_VERSION_MIN_REQUIRED
+			if ( context.processUsingLibraryValidation ) {
+				dyld::throwf("cannot load image with wrong team ID in process using Library Validation");
 			}
 			else
-				dyld::throwf("mmap() errno=%d validating first page of '%s'", errnoCopy, getPath());
+#endif
+			{
+				int errnoCopy = errno;
+				if ( errnoCopy == EPERM ) {
+					if ( dyld::sandboxBlockedMmap(getPath()) )
+						dyld::throwf("file system sandbox blocked mmap() of '%s'", getPath());
+					else
+						dyld::throwf("code signing blocked mmap() of '%s'", getPath());
+				}
+				else
+					dyld::throwf("mmap() errno=%d validating first page of '%s'", errnoCopy, getPath());
+			}
 		}
 		if ( memcmp(fdata, fileData, lenFileData) != 0 )
 			dyld::throwf("mmap() page compare failed for '%s'", getPath());
@@ -1225,7 +1202,7 @@
 	return NULL;
 }
 
-void ImageLoaderMachO::registerInterposing(const LinkContext& context)
+void ImageLoaderMachO::registerInterposing()
 {
 	// mach-o files advertise interposing by having a __DATA __interpose section
 	struct InterposeData { uintptr_t replacement; uintptr_t replacee; };
@@ -1281,7 +1258,6 @@
 	const struct load_command* const cmds = (struct load_command*)(((char*)mh) + sizeof(macho_header));
 	const struct load_command* cmd = cmds;
 	const struct version_min_command* versCmd;
-	const struct build_version_command* buildVersCmd;
 	for (uint32_t i = 0; i < cmd_count; ++i) {
 		switch ( cmd->cmd ) {
 			case LC_VERSION_MIN_MACOSX:
@@ -1290,9 +1266,6 @@
 			case LC_VERSION_MIN_WATCHOS:
 				versCmd = (version_min_command*)cmd;
 				return versCmd->sdk;
-			case LC_BUILD_VERSION:
-				buildVersCmd = (build_version_command*)cmd;
-				return buildVersCmd->sdk;
 		}
 		cmd = (const struct load_command*)(((char*)cmd)+cmd->cmdsize);
 	}
@@ -1310,7 +1283,6 @@
 	const struct load_command* const cmds = (struct load_command*)(((char*)mh) + sizeof(macho_header));
 	const struct load_command* cmd = cmds;
 	const struct version_min_command* versCmd;
-	const struct build_version_command* buildVersCmd;
 	for (uint32_t i = 0; i < cmd_count; ++i) {
 		switch ( cmd->cmd ) {
 			case LC_VERSION_MIN_MACOSX:
@@ -1319,9 +1291,6 @@
 			case LC_VERSION_MIN_WATCHOS:
 				versCmd = (version_min_command*)cmd;
 				return versCmd->version;
-			case LC_BUILD_VERSION:
-				buildVersCmd = (build_version_command*)cmd;
-				return buildVersCmd->minos;
 		}
 		cmd = (const struct load_command*)(((char*)cmd)+cmd->cmdsize);
 	}
@@ -1334,7 +1303,7 @@
 }
 
 
-void* ImageLoaderMachO::getEntryFromLC_MAIN() const
+void* ImageLoaderMachO::getThreadPC() const
 {
 	const uint32_t cmd_count = ((macho_header*)fMachOData)->ncmds;
 	const struct load_command* const cmds = (struct load_command*)&fMachOData[sizeof(macho_header)];
@@ -1344,13 +1313,8 @@
 			entry_point_command* mainCmd = (entry_point_command*)cmd;
 			void* entry = (void*)(mainCmd->entryoff + (char*)fMachOData);
 			// <rdar://problem/8543820&9228031> verify entry point is in image
-			if ( this->containsAddress(entry) ) {
-#if __has_feature(ptrauth_calls)
-				// start() calls the result pointer as a function pointer so we need to sign it.
-				return __builtin_ptrauth_sign_unauthenticated(entry, 0, 0);
-#endif
+			if ( this->containsAddress(entry) )
 				return entry;
-			}
 			else
 				throw "LC_MAIN entryoff is out of range";
 		}
@@ -1360,26 +1324,36 @@
 }
 
 
-void* ImageLoaderMachO::getEntryFromLC_UNIXTHREAD() const
+void* ImageLoaderMachO::getMain() const
 {
 	const uint32_t cmd_count = ((macho_header*)fMachOData)->ncmds;
 	const struct load_command* const cmds = (struct load_command*)&fMachOData[sizeof(macho_header)];
 	const struct load_command* cmd = cmds;
 	for (uint32_t i = 0; i < cmd_count; ++i) {
-		if ( cmd->cmd == LC_UNIXTHREAD ) {
-	#if __i386__
-			const i386_thread_state_t* registers = (i386_thread_state_t*)(((char*)cmd) + 16);
-			void* entry = (void*)(registers->eip + fSlide);
-			// <rdar://problem/8543820&9228031> verify entry point is in image
-			if ( this->containsAddress(entry) )
-				return entry;
-	#elif __x86_64__
-			const x86_thread_state64_t* registers = (x86_thread_state64_t*)(((char*)cmd) + 16);
-			void* entry = (void*)(registers->rip + fSlide);
-			// <rdar://problem/8543820&9228031> verify entry point is in image
-			if ( this->containsAddress(entry) )
-				return entry;
-	#endif
+		switch (cmd->cmd) {
+			case LC_UNIXTHREAD:
+			{
+			#if __i386__
+				const i386_thread_state_t* registers = (i386_thread_state_t*)(((char*)cmd) + 16);
+				void* entry = (void*)(registers->eip + fSlide);
+			#elif __x86_64__
+				const x86_thread_state64_t* registers = (x86_thread_state64_t*)(((char*)cmd) + 16);
+				void* entry = (void*)(registers->rip + fSlide);
+			#elif __arm__
+				const arm_thread_state_t* registers = (arm_thread_state_t*)(((char*)cmd) + 16);
+				void* entry = (void*)(registers->__pc + fSlide);
+			#elif __arm64__
+				const arm_thread_state64_t* registers = (arm_thread_state64_t*)(((char*)cmd) + 16);
+				void* entry = (void*)(registers->__pc + fSlide);
+			#else
+				#warning need processor specific code
+			#endif
+				// <rdar://problem/8543820&9228031> verify entry point is in image
+				if ( this->containsAddress(entry) ) {
+					return entry;
+				}
+			}
+			break;
 		}
 		cmd = (const struct load_command*)(((char*)cmd)+cmd->cmdsize);
 	}
@@ -1411,10 +1385,10 @@
 				{
 				const dylib_command* dylibID = (dylib_command*)cmd;
 				const char* installPath = (char*)cmd + dylibID->dylib.name.offset;
-				// It is OK for OS dylibs (libSystem or libmath) to have no dependents
+				// It is OK for OS dylibs (libSystem or libmath or Rosetta shims) to have no dependents
 				// but all other dylibs must depend on libSystem for initialization to initialize libSystem first
-				isNonOSdylib = ( (strncmp(installPath, "/usr/lib/", 9) != 0) && (strncmp(installPath, "/System/DriverKit/usr/lib/", 26) != 0) );
-				// if (isNonOSdylib) dyld::log("ImageLoaderMachO::needsAddedLibSystemDepency(%s)\n", installPath);
+				// <rdar://problem/6497528> rosetta circular dependency spew
+				isNonOSdylib = ( (strncmp(installPath, "/usr/lib/", 9) != 0) && (strncmp(installPath, "/usr/libexec/oah/Shims", 9) != 0) );
 				}
 				break;
 		}
@@ -1494,10 +1468,12 @@
 				const char* pathToAdd = NULL;
 				const char* path = (char*)cmd + ((struct rpath_command*)cmd)->path.offset;
 				if ( (strncmp(path, "@loader_path", 12) == 0) && ((path[12] == '/') || (path[12] == '\0')) ) {
-					if ( !context.allowAtPaths && (context.mainExecutable == this) ) {
-						dyld::warn("LC_RPATH %s in %s being ignored in restricted program because of @loader_path (Codesign main executable with Library Validation to allow @ paths)\n", path, this->getPath());
+#if __MAC_OS_X_VERSION_MIN_REQUIRED
+					if ( context.processIsRestricted && (context.mainExecutable == this) ) {
+						dyld::warn("LC_RPATH %s in %s being ignored in restricted program because of @loader_path\n", path, this->getPath());
 						break;
 					}
+#endif
 					char resolvedPath[PATH_MAX];
 					if ( realpath(this->getPath(), resolvedPath) != NULL ) {
 						char newRealPath[strlen(resolvedPath) + strlen(path)];
@@ -1510,10 +1486,12 @@
 					}
 				}
 				else if ( (strncmp(path, "@executable_path", 16) == 0) && ((path[16] == '/') || (path[16] == '\0')) ) {
-					if ( !context.allowAtPaths) {
-						dyld::warn("LC_RPATH %s in %s being ignored in restricted program because of @executable_path (Codesign main executable with Library Validation to allow @ paths)\n", path, this->getPath());
+#if __MAC_OS_X_VERSION_MIN_REQUIRED
+					if ( context.processIsRestricted ) {
+						dyld::warn("LC_RPATH %s in %s being ignored in restricted program because of @executable_path\n", path, this->getPath());
 						break;
 					}
+#endif
 					char resolvedPath[PATH_MAX];
 					if ( realpath(context.mainExecutable->getPath(), resolvedPath) != NULL ) {
 						char newRealPath[strlen(resolvedPath) + strlen(path)];
@@ -1525,38 +1503,36 @@
 						}
 					}
 				}
-				else if ( (path[0] != '/') && !context.allowAtPaths) {
+#if __MAC_OS_X_VERSION_MIN_REQUIRED
+				else if ( (path[0] != '/') && context.processIsRestricted ) {
 					dyld::warn("LC_RPATH %s in %s being ignored in restricted program because it is a relative path\n", path, this->getPath());
 					break;
 				}
+#endif
 #if SUPPORT_ROOT_PATH
 				else if ( (path[0] == '/') && (context.rootPaths != NULL) ) {
 					// <rdar://problem/5869973> DYLD_ROOT_PATH should apply to LC_RPATH rpaths
-					// <rdar://problem/49576123> Even if DYLD_ROOT_PATH exists, LC_RPATH should add raw path to rpaths
 					// DYLD_ROOT_PATH can be a list of paths, but at this point we can only support one, so use first combination that exists
-					for (const char** rp = context.rootPaths; *rp != NULL; ++rp) {
+					bool found = false;
+					for(const char** rp = context.rootPaths; *rp != NULL; ++rp) {
 						char newPath[PATH_MAX];
 						strlcpy(newPath, *rp, PATH_MAX);
 						strlcat(newPath, path, PATH_MAX);
 						struct stat stat_buf;
-						if ( dyld3::stat(newPath, &stat_buf) != -1 ) {
-							// dyld::log("combined DYLD_ROOT_PATH and LC_RPATH: %s\n", newPath);
-							paths.push_back(strdup(newPath));
+						if ( stat(newPath, &stat_buf) != -1 ) {
+							//dyld::log("combined DYLD_ROOT_PATH and LC_RPATH: %s\n", newPath);
+							pathToAdd = strdup(newPath);
+							found = true;
+							break;
 						}
 					}
-					// add in raw absolute path without root prefix
-					pathToAdd = strdup(path);
+					if ( ! found ) {
+						// make copy so that all elements of 'paths' can be freed
+						pathToAdd = strdup(path);
+					}
 				}
 #endif
 				else {
-					// realpath() is slow, and /usr/lib/swift is a real path, so don't realpath it
-					if ( strcmp(path, "/usr/lib/swift") != 0 ) {
-						char resolvedPath[PATH_MAX];
-						if ( (realpath(path, resolvedPath) != NULL) && (strcmp(path, resolvedPath) != 0) ) {
-							// <rdar://problem/45470293> support LC_RPATH symlinks to directories of things in the dyld cache
-							path = resolvedPath;
-						}
-					}
 					// make copy so that all elements of 'paths' can be freed
 					pathToAdd = strdup(path);
 				}
@@ -1593,10 +1569,6 @@
 	if ( fRetainForObjC )
 		this->setNeverUnload();
 
-    // dylibs with thread local variables cannot be unloaded because there is no way to clean up all threads
-    if ( !this->inSharedCache() && (this->machHeader()->flags & MH_HAS_TLV_DESCRIPTORS) )
-        this->setNeverUnload();
-
 	// if prebound and loaded at prebound address, then no need to rebase
 	if ( this->usablePrebinding(context) ) {
 		// skip rebasing because prebinding is valid
@@ -1633,7 +1605,7 @@
 #endif
 
 	// if loaded at preferred address, no rebasing necessary
-	if ( this->fSlide == 0 )
+	if ( this->fSlide == 0 ) 
 		return;
 
 #if TEXT_RELOC_SUPPORT
@@ -1822,7 +1794,7 @@
 	for (uint32_t i = 0; i < cmd_count; ++i) {
 		if ( cmd->cmd == LC_SEGMENT_COMMAND ) {
 			const macho_segment_command* seg = (macho_segment_command*)cmd;
-			if ( strcmp(seg->segname, "__TEXT") == 0 )
+			if ( (seg->fileoff == 0) && (seg->filesize != 0) )
 				return (char*)mh - (char*)(seg->vmaddr);
 		}
 		cmd = (const load_command*)(((char*)cmd)+cmd->cmdsize);
@@ -1858,7 +1830,7 @@
 }
 
 
-const macho_section* ImageLoaderMachO::findSection(const void* imageInterior) const
+bool ImageLoaderMachO::findSection(const void* imageInterior, const char** segmentName, const char** sectionName, size_t* sectionOffset)
 {
 	const uint32_t cmd_count = ((macho_header*)fMachOData)->ncmds;
 	const struct load_command* const cmds = (struct load_command*)&fMachOData[sizeof(macho_header)];
@@ -1874,7 +1846,13 @@
 						const struct macho_section* const sectionsEnd = &sectionsStart[seg->nsects];
 						for (const struct macho_section* sect=sectionsStart; sect < sectionsEnd; ++sect) {
 							if ((sect->addr <= unslidInteriorAddress) && (unslidInteriorAddress < (sect->addr+sect->size))) {
-								return sect;
+								if ( segmentName != NULL )
+									*segmentName = sect->segname;
+								if ( sectionName != NULL )
+									*sectionName = sect->sectname;
+								if ( sectionOffset != NULL )
+									*sectionOffset = unslidInteriorAddress - sect->addr;
+								return true;
 							}
 						}
 					}
@@ -1882,22 +1860,6 @@
 				break;
 		}
 		cmd = (const struct load_command*)(((char*)cmd)+cmd->cmdsize);
-	}
-	return nullptr;
-}
-
-
-bool ImageLoaderMachO::findSection(const void* imageInterior, const char** segmentName, const char** sectionName, size_t* sectionOffset)
-{
-	if (const struct macho_section* sect = findSection(imageInterior)) {
-		const uintptr_t unslidInteriorAddress = (uintptr_t)imageInterior - this->getSlide();
-		if ( segmentName != NULL )
-			*segmentName = sect->segname;
-		if ( sectionName != NULL )
-			*sectionName = sect->sectname;
-		if ( sectionOffset != NULL )
-			*sectionOffset = unslidInteriorAddress - sect->addr;
-		return true;
 	}
 	return false;
 }
@@ -1967,29 +1929,24 @@
 	return (const void*)lastAddress;
 }
 
-uintptr_t ImageLoaderMachO::bindLocation(const LinkContext& context, uintptr_t baseVMAddress,
-                                         uintptr_t location, uintptr_t value,
-                                         uint8_t type, const char* symbolName,
-                                         intptr_t addend, const char* inPath, const char* toPath, const char* msg,
-                                         ExtraBindData *extraBindData, uintptr_t slide)
-{
-    auto logBind = [&]() {
-        if ( !context.verboseBind )
-            return;
-        if ( addend != 0 ) {
-            dyld::log("dyld: %sbind: %s:0x%08lX = %s:%s, *0x%08lX = 0x%08lX + %ld\n",
-                      msg, shortName(inPath), (uintptr_t)location,
-                      ((toPath != NULL) ? shortName(toPath) : "<missing weak_import>"),
-                      symbolName, (uintptr_t)location, value, addend);
-        } else {
-            dyld::log("dyld: %sbind: %s:0x%08lX = %s:%s, *0x%08lX = 0x%08lX\n",
-                      msg, shortName(inPath), (uintptr_t)location,
-                      ((toPath != NULL) ? shortName(toPath) : "<missing weak_import>"),
-                      symbolName, (uintptr_t)location, value);
-        }
-    };
-
-
+
+uintptr_t ImageLoaderMachO::bindLocation(const LinkContext& context, uintptr_t location, uintptr_t value, 
+										uint8_t type, const char* symbolName,
+										intptr_t addend, const char* inPath, const char* toPath, const char* msg)
+{
+	// log
+	if ( context.verboseBind ) {
+		if ( addend != 0 )
+			dyld::log("dyld: %sbind: %s:0x%08lX = %s:%s, *0x%08lX = 0x%08lX + %ld\n",
+						msg, shortName(inPath), (uintptr_t)location,
+						((toPath != NULL) ? shortName(toPath) : "<missing weak_import>"),
+						symbolName, (uintptr_t)location, value, addend);
+		else
+			dyld::log("dyld: %sbind: %s:0x%08lX = %s:%s, *0x%08lX = 0x%08lX\n",
+						msg, shortName(inPath), (uintptr_t)location,
+						((toPath != NULL) ? shortName(toPath) : "<missing weak_import>"),
+						 symbolName, (uintptr_t)location, value);
+	}
 #if LOG_BINDINGS
 //	dyld::logBindings("%s: %s\n", targetImage->getShortName(), symbolName);
 #endif
@@ -2001,45 +1958,22 @@
 	uint32_t value32;
 	switch (type) {
 		case BIND_TYPE_POINTER:
-            logBind();
 			// test first so we don't needless dirty pages
 			if ( *locationToFix != newValue )
 				*locationToFix = newValue;
 			break;
-        case BIND_TYPE_TEXT_ABSOLUTE32:
-            logBind();
+		case BIND_TYPE_TEXT_ABSOLUTE32:
 			loc32 = (uint32_t*)locationToFix;
 			value32 = (uint32_t)newValue;
 			if ( *loc32 != value32 )
 				*loc32 = value32;
 			break;
-        case BIND_TYPE_TEXT_PCREL32:
-            logBind();
+		case BIND_TYPE_TEXT_PCREL32:
 			loc32 = (uint32_t*)locationToFix;
 			value32 = (uint32_t)(newValue - (((uintptr_t)locationToFix) + 4));
 			if ( *loc32 != value32 )
 				*loc32 = value32;
-            break;
-        case BIND_TYPE_THREADED_BIND:
-            logBind();
-            // test first so we don't needless dirty pages
-            if ( *locationToFix != newValue )
-                *locationToFix = newValue;
-            break;
-        case BIND_TYPE_THREADED_REBASE: {
-            // Regular pointer which needs to fit in 51-bits of value.
-            // C++ RTTI uses the top bit, so we'll allow the whole top-byte
-            // and the signed-extended bottom 43-bits to be fit in to 51-bits.
-            uint64_t top8Bits = *locationToFix & 0x0007F80000000000ULL;
-            uint64_t bottom43Bits = *locationToFix & 0x000007FFFFFFFFFFULL;
-            uint64_t targetValue = ( top8Bits << 13 ) | (((intptr_t)(bottom43Bits << 21) >> 21) & 0x00FFFFFFFFFFFFFF);
-            newValue = (uintptr_t)(targetValue + slide);
-            if ( context.verboseRebase ) {
-                dyld::log("dyld: rebase: %s:*0x%08lX += 0x%08lX = 0x%08lX\n", shortName(inPath), (uintptr_t)locationToFix, slide, newValue);
-            }
-            *locationToFix = newValue;
 			break;
-        }
 		default:
 			dyld::throwf("bad bind type %d", type);
 	}
@@ -2070,17 +2004,7 @@
 
 // These are defined in dyldStartup.s
 extern "C" void stub_binding_helper();
-extern "C" int _dyld_func_lookup(const char* name, void** address);
-
-static const char* libDyldPath(const ImageLoader::LinkContext& context)
-{
-#if TARGET_OS_OSX
-	if ( context.driverKit )
-		return DRIVERKIT_LIBDYLD_DYLIB_PATH;
-	else
-#endif
-	return LIBDYLD_DYLIB_PATH;
-}
+
 
 void ImageLoaderMachO::setupLazyPointerHandler(const LinkContext& context)
 {
@@ -2108,24 +2032,6 @@
 									dd->dyldLazyBinder = (void*)&stub_binding_helper;
 							}
 				#endif // !__arm64__
-							// <rdar://problem/40352925> Add work around for existing apps that have deprecated __dyld section
-							const char* installNm = this->getInstallPath();
-							if ( (mh->filetype != MH_DYLIB) || (installNm == NULL) || (strcmp(installNm, libDyldPath(context)) != 0) ) {
-						#if TARGET_OS_OSX
-								// don't allow macOS apps build with 10.14 or later SDK and targeting 10.8 or later to have a __dyld section
-								if ( (minOSVersion() >= 0x000a0800) && (sdkVersion() >= 0x000a0e00) )
-									dyld::throwf("__dyld section not supported in %s", this->getPath());
-						#endif
-						#if TARGET_OS_IOS || TARGET_OS_TV
-								// don't allow iOS apps build with 12.0 or later SDK to have a __dyld section
-								if ( sdkVersion() >= 0x000c0000 )
-									dyld::throwf("__dyld section not supported in %s", this->getPath());
-						#endif
-						#if TARGET_OS_WATCH
-								if ( sdkVersion() >= 0x00050000 )
-									dyld::throwf("__dyld section not supported in %s", this->getPath());
-						#endif
-							}
 							if ( sect->size > offsetof(DATAdyld, dyldFuncLookup) ) {
 								if ( dd->dyldFuncLookup != (void*)&_dyld_func_lookup )
 									dd->dyldFuncLookup = (void*)&_dyld_func_lookup;
@@ -2145,7 +2051,7 @@
 									// match what crt1.o supplies, then the program has a custom entry point.
 									// This means it might be doing something that needs to be executed before 
 									// initializers are run. 
-									if ( memcmp(this->getEntryFromLC_UNIXTHREAD(), sStandardEntryPointInstructions, 16) != 0 ) {
+									if ( memcmp(this->getMain(), sStandardEntryPointInstructions, 16) != 0 ) {
 										if ( context.verboseInit )
 											dyld::log("dyld: program uses non-standard entry point so delaying running of initializers\n");
 										context.setRunInitialzersOldWay();
@@ -2155,7 +2061,7 @@
 							}
 							else if ( mh->filetype == MH_DYLIB ) {
 								const char* installPath = this->getInstallPath();
-								if ( (installPath != NULL) && ((strncmp(installPath, "/usr/lib/", 9) == 0) || (strncmp(installPath, "/System/DriverKit/usr/lib/", 26) == 0)) ) {
+								if ( (installPath != NULL) && (strncmp(installPath, "/usr/lib/", 9) == 0) ) {
 									if ( sect->size > offsetof(DATAdyld, vars) ) {
 										// use ProgramVars from libdyld.dylib but tweak mh field to correct value
 										dd->vars.mh = context.mainExecutable->machHeader();
@@ -2212,9 +2118,10 @@
 
 bool ImageLoaderMachO::usablePrebinding(const LinkContext& context) const
 {
-	// dylibs in dyld cache do not need to be rebased or bound
-	// for chained fixups always pretend dylib is up to date, patch tables will be used later
-	if ( fInSharedCache && (this->allDependentLibrariesAsWhenPreBound() || context.dyldCache->header.builtFromChainedFixups) ) {
+	// if prebound and loaded at prebound address, and all libraries are same as when this was prebound, then no need to bind
+	if ( ((this->isPrebindable() && (this->getSlide() == 0)) || fInSharedCache)
+		&& this->usesTwoLevelNameSpace()
+		&& this->allDependentLibrariesAsWhenPreBound() ) {
 		// allow environment variables to disable prebinding
 		if ( context.bindFlat )
 			return false;
@@ -2232,14 +2139,6 @@
 	return false;
 }
 
-static void *stripPointer(void *ptr) {
-#if __has_feature(ptrauth_calls)
-    return __builtin_ptrauth_strip(ptr, ptrauth_key_asia);
-#else
-    return ptr;
-#endif
-}
-
 
 void ImageLoaderMachO::doImageInit(const LinkContext& context)
 {
@@ -2251,11 +2150,8 @@
 			switch (cmd->cmd) {
 				case LC_ROUTINES_COMMAND:
 					Initializer func = (Initializer)(((struct macho_routines_command*)cmd)->init_address + fSlide);
-#if __has_feature(ptrauth_calls)
-					func = (Initializer)__builtin_ptrauth_sign_unauthenticated((void*)func, ptrauth_key_asia, 0);
-#endif
 					// <rdar://problem/8543820&9228031> verify initializers are in image
-					if ( ! this->containsAddress(stripPointer((void*)func)) ) {
+					if ( ! this->containsAddress((void*)func) ) {
 						dyld::throwf("initializer function %p not in mapped image for %s\n", func, this->getPath());
 					}
 					if ( ! dyld::gProcessInfo->libSystemInitialized ) {
@@ -2264,28 +2160,13 @@
 					}
 					if ( context.verboseInit )
 						dyld::log("dyld: calling -init function %p in %s\n", func, this->getPath());
-					{
-						dyld3::ScopedTimer(DBG_DYLD_TIMING_STATIC_INITIALIZER, (uint64_t)fMachOData, (uint64_t)func, 0);
-						func(context.argc, context.argv, context.envp, context.apple, &context.programVars);
-					}
+					func(context.argc, context.argv, context.envp, context.apple, &context.programVars);
 					break;
 			}
 			cmd = (const struct load_command*)(((char*)cmd)+cmd->cmdsize);
 		}
 	}
 }
-
-static const char* libSystemPath(const ImageLoader::LinkContext& context)
-{
-#if TARGET_OS_OSX
-	if ( context.driverKit )
-		return DRIVERKIT_LIBSYSTEM_DYLIB_PATH;
-	else
-#endif
-	return LIBSYSTEM_DYLIB_PATH;
-}
-
-
 
 void ImageLoaderMachO::doModInitFunctions(const LinkContext& context)
 {
@@ -2309,60 +2190,19 @@
 						for (size_t j=0; j < count; ++j) {
 							Initializer func = inits[j];
 							// <rdar://problem/8543820&9228031> verify initializers are in image
-							if ( ! this->containsAddress(stripPointer((void*)func)) ) {
+							if ( ! this->containsAddress((void*)func) ) {
 								dyld::throwf("initializer function %p not in mapped image for %s\n", func, this->getPath());
 							}
 							if ( ! dyld::gProcessInfo->libSystemInitialized ) {
 								// <rdar://problem/17973316> libSystem initializer must run first
 								const char* installPath = getInstallPath();
-								if ( (installPath == NULL) || (strcmp(installPath, libSystemPath(context)) != 0) )
+								if ( (installPath == NULL) || (strcmp(installPath, LIBSYSTEM_DYLIB_PATH) != 0) )
 									dyld::throwf("initializer in image (%s) that does not link with libSystem.dylib\n", this->getPath());
 							}
 							if ( context.verboseInit )
 								dyld::log("dyld: calling initializer function %p in %s\n", func, this->getPath());
 							bool haveLibSystemHelpersBefore = (dyld::gLibSystemHelpers != NULL);
-							{
-								dyld3::ScopedTimer(DBG_DYLD_TIMING_STATIC_INITIALIZER, (uint64_t)fMachOData, (uint64_t)func, 0);
-								func(context.argc, context.argv, context.envp, context.apple, &context.programVars);
-							}
-							bool haveLibSystemHelpersAfter = (dyld::gLibSystemHelpers != NULL);
-							if ( !haveLibSystemHelpersBefore && haveLibSystemHelpersAfter ) {
-								// now safe to use malloc() and other calls in libSystem.dylib
-								dyld::gProcessInfo->libSystemInitialized = true;
-							}
-						}
-					}
-					else if ( type == S_INIT_FUNC_OFFSETS ) {
-						const uint32_t* inits = (uint32_t*)(sect->addr + fSlide);
-						const size_t count = sect->size / sizeof(uint32_t);
-						// Ensure section is within segment
-						if ( (sect->addr < seg->vmaddr) || (sect->addr+sect->size > seg->vmaddr+seg->vmsize) || (sect->addr+sect->size < sect->addr) )
-							dyld::throwf("__init_offsets section has malformed address range for %s\n", this->getPath());
-						if ( seg->initprot & VM_PROT_WRITE )
-							dyld::throwf("__init_offsets section is not in read-only segment %s\n", this->getPath());
-						for (size_t j=0; j < count; ++j) {
-							uint32_t funcOffset = inits[j];
-							// verify initializers are in image
-							if ( ! this->containsAddress((uint8_t*)this->machHeader() + funcOffset) ) {
-								dyld::throwf("initializer function offset 0x%08X not in mapped image for %s\n", funcOffset, this->getPath());
-							}
-							if ( ! dyld::gProcessInfo->libSystemInitialized ) {
-								// <rdar://problem/17973316> libSystem initializer must run first
-								const char* installPath = getInstallPath();
-								if ( (installPath == NULL) || (strcmp(installPath, libSystemPath(context)) != 0) )
-									dyld::throwf("initializer in image (%s) that does not link with libSystem.dylib\n", this->getPath());
-							}
-                            Initializer func = (Initializer)((uint8_t*)this->machHeader() + funcOffset);
-							if ( context.verboseInit )
-								dyld::log("dyld: calling initializer function %p in %s\n", func, this->getPath());
-#if __has_feature(ptrauth_calls)
-							func = (Initializer)__builtin_ptrauth_sign_unauthenticated((void*)func, ptrauth_key_asia, 0);
-#endif
-							bool haveLibSystemHelpersBefore = (dyld::gLibSystemHelpers != NULL);
-							{
-								dyld3::ScopedTimer(DBG_DYLD_TIMING_STATIC_INITIALIZER, (uint64_t)fMachOData, (uint64_t)func, 0);
-                                func(context.argc, context.argv, context.envp, context.apple, &context.programVars);
-                            }
+							func(context.argc, context.argv, context.envp, context.apple, &context.programVars);
 							bool haveLibSystemHelpersAfter = (dyld::gLibSystemHelpers != NULL);
 							if ( !haveLibSystemHelpersBefore && haveLibSystemHelpersAfter ) {
 								// now safe to use malloc() and other calls in libSystem.dylib
@@ -2460,11 +2300,8 @@
 						const size_t count = sect->size / sizeof(uintptr_t);
 						for (size_t j=count; j > 0; --j) {
 							Terminator func = terms[j-1];
-#if __has_feature(ptrauth_calls)
-							func = (Terminator)__builtin_ptrauth_sign_unauthenticated((void*)func, ptrauth_key_asia, 0);
-#endif
 							// <rdar://problem/8543820&9228031> verify terminators are in image
-							if ( ! this->containsAddress(stripPointer((void*)func)) ) {
+							if ( ! this->containsAddress((void*)func) ) {
 								dyld::throwf("termination function %p not in mapped image for %s\n", func, this->getPath());
 							}
 							if ( context.verboseInit )
@@ -2489,13 +2326,13 @@
 	dyld::log("total images using weak symbols:  %u\n", fgImagesRequiringCoalescing);
 }
 
-intptr_t ImageLoaderMachO::assignSegmentAddresses(const LinkContext& context, size_t extraAllocationSize)
+
+intptr_t ImageLoaderMachO::assignSegmentAddresses(const LinkContext& context)
 {
 	// preflight and calculate slide if needed
 	const bool inPIE = (fgNextPIEDylibAddress != 0);
 	intptr_t slide = 0;
 	if ( this->segmentsCanSlide() && this->segmentsMustSlideTogether() ) {
-		intptr_t segmentReAlignSlide = 0;
 		bool needsToSlide = false;
 		bool imageHasPreferredLoadAddress = segHasPreferredLoadAddress(0);
 		uintptr_t lowAddr = (unsigned long)(-1);
@@ -2513,53 +2350,22 @@
 				lowAddr = segLow;
 			if ( segHigh > highAddr )
 				highAddr = segHigh;
-
-#if defined(__x86_64__) && !TARGET_OS_SIMULATOR
-			// For Cambria on Aruba systems (16k page size), realign the image so the first segment ends on a 16k boundry.
-			// FIXME: this can be removed when Aruba dev systems are no longer supported.
-			if ( dyld::isTranslated() && vm_page_size == 0x4000 && i == 0 && segLow == 0 ) {
-				const uintptr_t segHighPageOffset = segHigh & vm_page_mask;
-				if ( segHighPageOffset > 0 ) {
-					// Adjust the slide to make the first segment end on a page boundry.
-					needsToSlide = true;
-					segmentReAlignSlide = vm_page_size - segHighPageOffset;
-
-					if (context.verboseMapping) {
-						dyld::log("dyld: Image %s first segment(%s) does not end on a page boundry [0x%lx, 0x%lx) adding 0x%lx to slide to realign\n", getPath(), segName(i), segLow, segHigh, segmentReAlignSlide);
-					}
-				}
-			}
-#endif
+				
 			if ( needsToSlide || !imageHasPreferredLoadAddress || inPIE || !reserveAddressRange(segPreferredLoadAddress(i), segSize(i)) )
 				needsToSlide = true;
 		}
 		if ( needsToSlide ) {
 			// find a chunk of address space to hold all segments
-			size_t size = highAddr-lowAddr+segmentReAlignSlide;
-			uintptr_t addr = reserveAnAddressRange(size+extraAllocationSize, context);
-			slide = addr - lowAddr + segmentReAlignSlide;
-		} else if ( extraAllocationSize ) {
-			if (!reserveAddressRange(highAddr, extraAllocationSize)) {
-				throw "failed to reserve space for aot";
-			}
+			uintptr_t addr = reserveAnAddressRange(highAddr-lowAddr, context);
+			slide = addr - lowAddr;
 		}
 	} 
 	else if ( ! this->segmentsCanSlide() ) {
-		uintptr_t highAddr = 0;
 		for(unsigned int i=0, e=segmentCount(); i < e; ++i) {
-			const uintptr_t segLow = segPreferredLoadAddress(i);
-			const uintptr_t segHigh = dyld_page_round(segLow + segSize(i));
-
-			if ( segHigh > highAddr )
-				highAddr = segHigh;
-
 			if ( (strcmp(segName(i), "__PAGEZERO") == 0) && (segFileSize(i) == 0) && (segPreferredLoadAddress(i) == 0) )
 				continue;
 			if ( !reserveAddressRange(segPreferredLoadAddress(i), segSize(i)) )
 				dyld::throwf("can't map unslidable segment %s to 0x%lX with size 0x%lX", segName(i), segPreferredLoadAddress(i), segSize(i));
-		}
-		if (extraAllocationSize) {
-			dyld::throwf("binaries with non-slidable segments don't support aot: %s", this->getPath());
 		}
 	}
 	else {
@@ -2602,61 +2408,28 @@
 	return true;
 }
 
+
+
 void ImageLoaderMachO::mapSegments(int fd, uint64_t offsetInFat, uint64_t lenInFat, uint64_t fileLen, const LinkContext& context)
 {
-	uint64_t extra_allocation_size = 0;
-
-#if defined(__x86_64__) && !TARGET_OS_SIMULATOR
-	if (dyld::isTranslated()) {
-		fAotPath = new char[PATH_MAX];
-		int ret = syscall(0x7000001, fd, this->getPath(), &extra_allocation_size, fAotPath, PATH_MAX);
-		if (ret != 0) {
-			delete fAotPath;
-			fAotPath = nullptr;
-		}
-	}
-#endif
-
 	// find address range for image
-	intptr_t slide = this->assignSegmentAddresses(context, extra_allocation_size);
+	intptr_t slide = this->assignSegmentAddresses(context);
 	if ( context.verboseMapping ) {
 		if ( offsetInFat != 0 )
 			dyld::log("dyld: Mapping %s (slice offset=%llu)\n", this->getPath(), (unsigned long long)offsetInFat);
 		else
 			dyld::log("dyld: Mapping %s\n", this->getPath());
 	}
-
-	// <rdar://problem/47163421> speculatively read whole slice
-	fspecread_t specread = {} ;
-	specread.fsr_offset = offsetInFat;
-	specread.fsr_length = lenInFat;
-	specread.fsr_flags  = 0;
-	fcntl(fd, F_SPECULATIVE_READ, &specread);
-	if ( context.verboseMapping )
-		dyld::log("dyld: Speculatively read offset=0x%08llX, len=0x%08llX, path=%s\n", offsetInFat, lenInFat, this->getPath());
-
 	// map in all segments
-	uintptr_t baseAddress = (unsigned long)(-1);
-	uintptr_t endAddress = 0;
-	uintptr_t mappedMachHeaderAddress = 0;
 	for(unsigned int i=0, e=segmentCount(); i < e; ++i) {
-		vm_offset_t fileOffset = (vm_offset_t)(segFileOffset(i) + offsetInFat);
+		vm_offset_t fileOffset = segFileOffset(i) + offsetInFat;
 		vm_size_t size = segFileSize(i);
 		uintptr_t requestedLoadAddress = segPreferredLoadAddress(i) + slide;
-		const uintptr_t segmentEnd = dyld_page_round(requestedLoadAddress + segSize(i));
-
-		if ( requestedLoadAddress < baseAddress )
-			baseAddress = requestedLoadAddress;
-		if ( segmentEnd > endAddress )
-			endAddress = segmentEnd;
-
-		if (segFileOffset(i) == 0 && segFileSize(i) != 0) {
-			mappedMachHeaderAddress = requestedLoadAddress;
-		}
-
 		int protection = 0;
 		if ( !segUnaccessible(i) ) {
-			if ( segExecutable(i) )
+			// If has text-relocs, don't set x-bit initially.
+			// Instead set it later after text-relocs have been done.
+			if ( segExecutable(i) && !(segHasRebaseFixUps(i) && (slide != 0)) )
 				protection   |= PROT_EXEC;
 			if ( segReadable(i) )
 				protection   |= PROT_READ;
@@ -2700,24 +2473,6 @@
 				(protection & PROT_READ) ? 'r' : '.',  (protection & PROT_WRITE) ? 'w' : '.',  (protection & PROT_EXEC) ? 'x' : '.' );
 	}
 
-#if defined(__x86_64__) && !TARGET_OS_SIMULATOR
-	if (dyld::isTranslated() && extra_allocation_size != 0) {
-		const struct mach_header* aot_load_address;
-		dyld_aot_image_info aot_image_info = {};
-		int ret = syscall(0x7000002, this->getPath(), mappedMachHeaderAddress, endAddress, &aot_load_address, &aot_image_info.aotImageSize, aot_image_info.aotImageKey);
-		if (ret == 0) {
-			extern void addAotImagesToAllAotImages(uint32_t aotInfoCount, const dyld_aot_image_info aotInfo[]);
-
-			// fill in the aot load address, at this point the cambria trap has filled in
-			// the image size and image key fields
-			aot_image_info.aotLoadAddress = aot_load_address;
-			aot_image_info.x86LoadAddress = (struct mach_header*)baseAddress;
-
-			addAotImagesToAllAotImages(1, &aot_image_info);
-		}
-	}
-#endif
-
 	// update slide to reflect load location			
 	this->setSlide(slide);
 }
@@ -2725,7 +2480,7 @@
 void ImageLoaderMachO::mapSegments(const void* memoryImage, uint64_t imageLen, const LinkContext& context)
 {
 	// find address range for image
-	intptr_t slide = this->assignSegmentAddresses(context, 0);
+	intptr_t slide = this->assignSegmentAddresses(context);
 	if ( context.verboseMapping )
 		dyld::log("dyld: Mapping memory %p\n", memoryImage);
 	// map in all segments
@@ -2743,52 +2498,24 @@
 	this->setSlide(slide);
 	// set R/W permissions on all segments at slide location
 	for(unsigned int i=0, e=segmentCount(); i < e; ++i) {
-		segProtect(i, context);
-	}
-}
-
-static vm_prot_t protectionForSegIndex(const ImageLoaderMachO* image, unsigned int segIndex)
-{
-	if ( image->segUnaccessible(segIndex) )
-		return 0;
+		segProtect(i, context);		
+	}
+}
+
+
+void ImageLoaderMachO::segProtect(unsigned int segIndex, const ImageLoader::LinkContext& context)
+{
 	vm_prot_t protection = 0;
-	if ( image->segExecutable(segIndex) )
-		protection |= PROT_EXEC;
-	if ( image->segReadable(segIndex) )
-		protection |= PROT_READ;
-	if ( image->segWriteable(segIndex) )
-		protection |= PROT_WRITE;
-	return protection;
-}
-
-
-void ImageLoaderMachO::segProtect(unsigned int segIndex, const ImageLoader::LinkContext& context)
-{
-	vm_prot_t protection = protectionForSegIndex(this, segIndex);
+	if ( !segUnaccessible(segIndex) ) {
+		if ( segExecutable(segIndex) )
+			protection   |= PROT_EXEC;
+		if ( segReadable(segIndex) )
+			protection   |= PROT_READ;
+		if ( segWriteable(segIndex) )
+			protection   |= PROT_WRITE;
+	}
 	vm_address_t addr = segActualLoadAddress(segIndex);
 	vm_size_t size = segSize(segIndex);
-
-#if defined(__x86_64__) && !TARGET_OS_SIMULATOR
-	if ( dyld::isTranslated() ) {
-		// <rdar://problem/60543794> can't vm_protect non-16KB segments
-		if ( (segIndex > 0) && ((addr & 0x3FFF) != 0) ) {
-			// overlaps previous segment
-			vm_prot_t prevProt = protectionForSegIndex(this, segIndex-1);
-			if ( (protection & prevProt) != prevProt ) {
-				// previous had more bits, so we need to not apply new permissions to the overlap
-				vm_size_t overlap = 0x4000 - (addr & 0x3FFF);
-				addr += overlap;
-				if ( size >= overlap )
-					size -= overlap;
-				else if ( size < overlap )
-					size = 0;
-			}
-			if ( size == 0 )
-				return;
-		}
-	}
-#endif
-
 	const bool setCurrentPermissions = false;
 	kern_return_t r = vm_protect(mach_task_self(), addr, size, setCurrentPermissions, protection);
 	if ( r != KERN_SUCCESS ) {
@@ -2801,13 +2528,12 @@
 	}
 }	
 
-#if TEXT_RELOC_SUPPORT
 void ImageLoaderMachO::segMakeWritable(unsigned int segIndex, const ImageLoader::LinkContext& context)
 {
 	vm_address_t addr = segActualLoadAddress(segIndex);
 	vm_size_t size = segSize(segIndex);
 	const bool setCurrentPermissions = false;
-	vm_prot_t protection = VM_PROT_WRITE | VM_PROT_READ | VM_PROT_COPY;
+	vm_prot_t protection = VM_PROT_WRITE | VM_PROT_READ;
 	if ( segExecutable(segIndex) && !segHasRebaseFixUps(segIndex) )
 		protection |= VM_PROT_EXECUTE;
 	kern_return_t r = vm_protect(mach_task_self(), addr, size, setCurrentPermissions, protection);
@@ -2820,7 +2546,7 @@
 			(protection & PROT_READ) ? 'r' : '.',  (protection & PROT_WRITE) ? 'w' : '.',  (protection & PROT_EXEC) ? 'x' : '.' );
 	}
 }
-#endif
+
 
 const char* ImageLoaderMachO::findClosestSymbol(const mach_header* mh, const void* addr, const void** closestAddr)
 {
@@ -2843,9 +2569,8 @@
 					unslidLinkEditBase = (uint8_t*)(seg->vmaddr - seg->fileoff);
 					linkEditBaseFound = true;
 				}
-				else if ( strcmp(seg->segname, "__TEXT") == 0 ) {
+				else if ( (seg->fileoff == 0) && (seg->filesize != 0) )
 					slide = (uintptr_t)mh - seg->vmaddr;
-                }
 				break;
 			case LC_SYMTAB:
 				symtab = (symtab_command*)cmd;
@@ -2913,6 +2638,8 @@
 {
 	if ( lazyBindingInfoOffset > (lazyInfoEnd-lazyInfoStart) )
 		return false;
+	uint8_t type = BIND_TYPE_POINTER;
+	uint8_t symboFlags = 0;
 	bool done = false;
 	const uint8_t* p = &lazyInfoStart[lazyBindingInfoOffset];
 	while ( !done && (p < lazyInfoEnd) ) {
@@ -2941,11 +2668,13 @@
 				break;
 			case BIND_OPCODE_SET_SYMBOL_TRAILING_FLAGS_IMM:
 				*symbolName = (char*)p;
+				symboFlags = immediate;
 				while (*p != '\0')
 					++p;
 				++p;
 				break;
 			case BIND_OPCODE_SET_TYPE_IMM:
+				type = immediate;
 				break;
 			case BIND_OPCODE_SET_SEGMENT_AND_OFFSET_ULEB:
 				*segIndex  = immediate;
@@ -3006,12 +2735,3 @@
 
 
 
-uintptr_t ImageLoaderMachO::imageBaseAddress() const {
-    //printf("imageBaseAddress: %s %d->%d\n", getPath(), 0, segmentCount());
-    for (unsigned int i = 0, e = segmentCount(); i != e; ++i) {
-        if ( (segFileOffset(i) == 0) && (segFileSize(i) != 0) )
-            return segPreferredLoadAddress(i);
-    }
-    return 0;
-}
-