#include <stdlib.h>
#include <sys/param.h>
#include <sys/fcntl.h>
+#include <sys/mman.h>
#include <sys/stat.h>
#include <errno.h>
#include <pthread.h>
#include <map>
#include <unordered_set>
#include <unordered_map>
+#include <iostream>
+#include <fstream>
#include "MachOFileAbstraction.hpp"
#include "Architectures.hpp"
#include "macho_relocatable_file.h"
#include "lto_file.h"
-// #defines are a work around for <rdar://problem/8760268>
-#define __STDC_LIMIT_MACROS 1
-#define __STDC_CONSTANT_MACROS 1
#include "llvm-c/lto.h"
namespace lto {
public:
InternalAtom(class File& f);
// overrides of ld::Atom
- virtual ld::File* file() const { return &_file; }
- virtual const char* name() const { return "import-atom"; }
- virtual uint64_t size() const { return 0; }
- virtual uint64_t objectAddress() const { return 0; }
- virtual void copyRawContent(uint8_t buffer[]) const { }
- virtual void setScope(Scope) { }
- virtual ld::Fixup::iterator fixupsBegin() const { return &_undefs[0]; }
- virtual ld::Fixup::iterator fixupsEnd() const { return &_undefs[_undefs.size()]; }
+ ld::File* file() const override { return &_file; }
+ const char* name() const override { return "import-atom"; }
+ uint64_t size() const override { return 0; }
+ uint64_t objectAddress() const override { return 0; }
+ void copyRawContent(uint8_t buffer[]) const override { }
+ ld::Fixup::iterator fixupsBegin() const override { return &_undefs[0]; }
+ ld::Fixup::iterator fixupsEnd() const override { return &_undefs[_undefs.size()]; }
// for adding references to symbols outside bitcode file
void addReference(const char* nm)
public:
File(const char* path, time_t mTime, ld::File::Ordinal ordinal,
const uint8_t* content, uint32_t contentLength, cpu_type_t arch);
- virtual ~File();
+ ~File() override;
// overrides of ld::File
- virtual bool forEachAtom(ld::File::AtomHandler&) const;
- virtual bool justInTimeforEachAtom(const char* name, ld::File::AtomHandler&) const
+ bool forEachAtom(ld::File::AtomHandler&) const override;
+ bool justInTimeforEachAtom(const char* name, ld::File::AtomHandler&) const override
{ return false; }
- virtual uint32_t cpuSubType() const { return _cpuSubType; }
+ uint32_t cpuSubType() const override { return _cpuSubType; }
// overrides of ld::relocatable::File
- virtual DebugInfoKind debugInfo() const { return _debugInfo; }
- virtual const char* debugInfoPath() const { return _debugInfoPath; }
- virtual time_t debugInfoModificationTime() const
+ DebugInfoKind debugInfo() const override { return _debugInfo; }
+ const char* debugInfoPath() const override { return _debugInfoPath; }
+ time_t debugInfoModificationTime() const override
{ return _debugInfoModTime; }
- virtual const std::vector<ld::relocatable::File::Stab>* stabs() const { return NULL; }
- virtual bool canScatterAtoms() const { return true; }
- virtual LinkerOptionsList* linkerOptions() const { return NULL; }
-
-
+ const std::vector<ld::relocatable::File::Stab>* stabs() const override { return NULL; }
+ bool canScatterAtoms() const override { return true; }
+ LinkerOptionsList* linkerOptions() const override { return NULL; }
+ const ToolVersionList& toolVersions() const override { return _toolVersions; }
+ bool isThinLTO() const { return _isThinLTO; }
+ void setIsThinLTO(bool ThinLTO) { _isThinLTO = ThinLTO; }
+ // fixme rdar://24734472 objCConstraint() and objcHasCategoryClassProperties()
void release();
lto_module_t module() { return _module; }
class InternalAtom& internalAtom() { return _internalAtom; }
static bool sSupportsLocalContext;
static bool sHasTriedLocalContext;
bool mergeIntoGenerator(lto_code_gen_t generator, bool useSetModule);
+#if LTO_API_VERSION >= 18
+ void addToThinGenerator(thinlto_code_gen_t generator, int id);
+#endif
private:
friend class Atom;
friend class InternalAtom;
friend class Parser;
-
+
+ bool _isThinLTO;
cpu_type_t _architecture;
class InternalAtom _internalAtom;
class Atom* _atomArray;
ld::Fixup _fixupToInternal;
ld::relocatable::File::DebugInfoKind _debugInfo;
uint32_t _cpuSubType;
+ ToolVersionList _toolVersions; // unused, may some day contain version of clang the created bitcode
};
//
ld::Atom::Definition d, ld::Atom::Combine c, ld::Atom::Alignment a, bool ah);
// overrides of ld::Atom
- virtual ld::File* file() const { return &_file; }
- virtual const char* translationUnitSource() const
+ const ld::File* file() const override { return (_compiledAtom ? _compiledAtom->file() : &_file ); }
+ const ld::File* originalFile() const override { return &_file; }
+ const char* translationUnitSource() const override
{ return (_compiledAtom ? _compiledAtom->translationUnitSource() : NULL); }
- virtual const char* name() const { return _name; }
- virtual uint64_t size() const { return (_compiledAtom ? _compiledAtom->size() : 0); }
- virtual uint64_t objectAddress() const { return (_compiledAtom ? _compiledAtom->objectAddress() : 0); }
- virtual void copyRawContent(uint8_t buffer[]) const
+ const char* name() const override { return _name; }
+ uint64_t size() const override { return (_compiledAtom ? _compiledAtom->size() : 0); }
+ uint64_t objectAddress() const override { return (_compiledAtom ? _compiledAtom->objectAddress() : 0); }
+ void copyRawContent(uint8_t buffer[]) const override
{ if (_compiledAtom) _compiledAtom->copyRawContent(buffer); }
- virtual const uint8_t* rawContentPointer() const
+ const uint8_t* rawContentPointer() const override
{ return (_compiledAtom ? _compiledAtom->rawContentPointer() : NULL); }
- virtual unsigned long contentHash(const class ld::IndirectBindingTable& ibt) const
+ unsigned long contentHash(const class ld::IndirectBindingTable& ibt) const override
{ return (_compiledAtom ? _compiledAtom->contentHash(ibt) : 0); }
- virtual bool canCoalesceWith(const ld::Atom& rhs, const class ld::IndirectBindingTable& ibt) const
+ bool canCoalesceWith(const ld::Atom& rhs, const class ld::IndirectBindingTable& ibt) const override
{ return (_compiledAtom ? _compiledAtom->canCoalesceWith(rhs,ibt) : false); }
- virtual ld::Fixup::iterator fixupsBegin() const
+ ld::Fixup::iterator fixupsBegin() const override
{ return (_compiledAtom ? _compiledAtom->fixupsBegin() : (ld::Fixup*)&_file._fixupToInternal); }
- virtual ld::Fixup::iterator fixupsEnd() const
+ ld::Fixup::iterator fixupsEnd() const override
{ return (_compiledAtom ? _compiledAtom->fixupsEnd() : &((ld::Fixup*)&_file._fixupToInternal)[1]); }
- virtual ld::Atom::UnwindInfo::iterator beginUnwind() const
+ ld::Atom::UnwindInfo::iterator beginUnwind() const override
{ return (_compiledAtom ? _compiledAtom->beginUnwind() : NULL); }
- virtual ld::Atom::UnwindInfo::iterator endUnwind() const
+ ld::Atom::UnwindInfo::iterator endUnwind() const override
{ return (_compiledAtom ? _compiledAtom->endUnwind() : NULL); }
- virtual ld::Atom::LineInfo::iterator beginLineInfo() const
+ ld::Atom::LineInfo::iterator beginLineInfo() const override
{ return (_compiledAtom ? _compiledAtom->beginLineInfo() : NULL); }
- virtual ld::Atom::LineInfo::iterator endLineInfo() const
+ ld::Atom::LineInfo::iterator endLineInfo() const override
{ return (_compiledAtom ? _compiledAtom->endLineInfo() : NULL); }
const ld::Atom* compiledAtom() { return _compiledAtom; }
std::vector<const ld::Atom*>& newAtoms,
std::vector<const char*>& additionalUndefines);
- static const char* ltoVersion() { return ::lto_get_version(); }
+ static const char* ltoVersion() { return ::lto_get_version(); }
private:
+
static const char* tripletPrefixForArch(cpu_type_t arch);
- static ld::relocatable::File* parseMachOFile(const uint8_t* p, size_t len, const OptimizeOptions& options);
+ static ld::relocatable::File* parseMachOFile(const uint8_t* p, size_t len, const std::string &path, const OptimizeOptions& options,
+ ld::File::Ordinal ordinal);
#if LTO_API_VERSION >= 7
static void ltoDiagnosticHandler(lto_codegen_diagnostic_severity_t, const char*, void*);
#endif
class AtomSyncer : public ld::File::AtomHandler {
public:
AtomSyncer(std::vector<const char*>& a, std::vector<const ld::Atom*>&na,
- CStringToAtom la, CStringToAtom dla, const OptimizeOptions& options) :
- _options(options), _additionalUndefines(a), _newAtoms(na), _llvmAtoms(la), _deadllvmAtoms(dla) { }
- virtual void doAtom(const class ld::Atom&);
- virtual void doFile(const class ld::File&) { }
+ const CStringToAtom &la, const CStringToAtom &dla, const OptimizeOptions& options) :
+ _options(options), _additionalUndefines(a), _newAtoms(na), _llvmAtoms(la), _deadllvmAtoms(dla), _lastProxiedAtom(NULL), _lastProxiedFile(NULL) {}
+ void doAtom(const class ld::Atom&) override;
+ void doFile(const class ld::File&) override { }
-
const OptimizeOptions& _options;
std::vector<const char*>& _additionalUndefines;
std::vector<const ld::Atom*>& _newAtoms;
- CStringToAtom _llvmAtoms;
- CStringToAtom _deadllvmAtoms;
+ const CStringToAtom &_llvmAtoms;
+ const CStringToAtom &_deadllvmAtoms;
+ const ld::Atom* _lastProxiedAtom;
+ const ld::File* _lastProxiedFile;
};
+ static void setPreservedSymbols(const std::vector<const ld::Atom*>& allAtoms,
+ ld::Internal& state,
+ const OptimizeOptions& options,
+ CStringToAtom &deadllvmAtoms,
+ CStringToAtom &llvmAtoms,
+ lto_code_gen_t generator);
+
+ static std::tuple<uint8_t *, size_t> codegen(const OptimizeOptions& options,
+ ld::Internal& state,
+ lto_code_gen_t generator,
+ std::string& object_path);
+
+
+ static void loadMachO(ld::relocatable::File* machoFile,
+ const OptimizeOptions& options,
+ ld::File::AtomHandler& handler,
+ std::vector<const ld::Atom*>& newAtoms,
+ std::vector<const char*>& additionalUndefines,
+ CStringToAtom &llvmAtoms,
+ CStringToAtom &deadllvmAtoms);
+
+ static bool optimizeLTO(const std::vector<File*> files,
+ const std::vector<const ld::Atom*>& allAtoms,
+ ld::Internal& state,
+ const OptimizeOptions& options,
+ ld::File::AtomHandler& handler,
+ std::vector<const ld::Atom*>& newAtoms,
+ std::vector<const char*>& additionalUndefines);
+
+ static bool optimizeThinLTO(const std::vector<File*>& Files,
+ const std::vector<const ld::Atom*>& allAtoms,
+ ld::Internal& state,
+ const OptimizeOptions& options,
+ ld::File::AtomHandler& handler,
+ std::vector<const ld::Atom*>& newAtoms,
+ std::vector<const char*>& additionalUndefines);
+
+#if LTO_API_VERSION >= 18
+ static thinlto_code_gen_t init_thinlto_codegen(const std::vector<File*>& files,
+ const std::vector<const ld::Atom*>& allAtoms,
+ ld::Internal& state,
+ const OptimizeOptions& options,
+ CStringToAtom& deadllvmAtoms,
+ CStringToAtom& llvmAtoms);
+#endif
+
static std::vector<File*> _s_files;
+ static bool _s_llvmOptionsProcessed;
};
std::vector<File*> Parser::_s_files;
+bool Parser::_s_llvmOptionsProcessed = false;
bool Parser::validFile(const uint8_t* fileContent, uint64_t fileLength, cpu_type_t architecture, cpu_subtype_t subarch)
}
-ld::relocatable::File* Parser::parseMachOFile(const uint8_t* p, size_t len, const OptimizeOptions& options)
+ld::relocatable::File* Parser::parseMachOFile(const uint8_t* p, size_t len, const std::string &path, const OptimizeOptions& options,
+ ld::File::Ordinal ordinal)
{
mach_o::relocatable::ParserOptions objOpts;
objOpts.architecture = options.arch;
objOpts.simulator = options.simulator;
objOpts.ignoreMismatchPlatform = options.ignoreMismatchPlatform;
objOpts.platform = options.platform;
+ objOpts.minOSVersion = options.minOSVersion;
objOpts.subType = 0;
objOpts.srcKind = ld::relocatable::File::kSourceLTO;
-
- // mach-o parsing is done in-memory, but need path for debug notes
- const char* path = "/tmp/lto.o";
+ objOpts.treateBitcodeAsData = false;
+ objOpts.usingBitcode = options.bitcodeBundle;
+ objOpts.maxDefaultCommonAlignment = options.maxDefaultCommonAlignment;
+
+ const char *object_path = path.c_str();
+ if (path.empty())
+ object_path = "/tmp/lto.o";
+
time_t modTime = 0;
- if ( options.tmpObjectFilePath != NULL ) {
- path = options.tmpObjectFilePath;
- struct stat statBuffer;
- if ( stat(options.tmpObjectFilePath, &statBuffer) == 0 )
- modTime = statBuffer.st_mtime;
- }
-
- ld::relocatable::File* result = mach_o::relocatable::parse(p, len, path, modTime, ld::File::Ordinal::LTOOrdinal(), objOpts);
+ struct stat statBuffer;
+ if ( stat(object_path, &statBuffer) == 0 )
+ modTime = statBuffer.st_mtime;
+
+ ld::relocatable::File* result = mach_o::relocatable::parse(p, len, strdup(object_path), modTime, ordinal, objOpts);
if ( result != NULL )
return result;
throw "LLVM LTO, file is not of required architecture";
File::File(const char* pth, time_t mTime, ld::File::Ordinal ordinal, const uint8_t* content, uint32_t contentLength, cpu_type_t arch)
- : ld::relocatable::File(pth,mTime,ordinal), _architecture(arch), _internalAtom(*this),
+ : ld::relocatable::File(pth,mTime,ordinal), _isThinLTO(false), _architecture(arch), _internalAtom(*this),
_atomArray(NULL), _atomArrayCount(0), _module(NULL), _path(pth),
_content(content), _contentLength(contentLength), _debugInfoPath(pth),
_section("__TEXT_", "__tmp_lto", ld::Section::typeTempLTO),
throwf("could not parse object file %s: '%s', using libLTO version '%s'", pth, ::lto_get_error_message(), ::lto_get_version());
if ( log ) fprintf(stderr, "bitcode file: %s\n", pth);
-
+
+#if LTO_API_VERSION >= 18
+ _isThinLTO = ::lto_module_is_thinlto(_module);
+#endif
+
// create atom for each global symbol in module
uint32_t count = ::lto_module_get_num_symbols(_module);
_atomArray = (Atom*)malloc(sizeof(Atom)*count);
return false;
}
+#if LTO_API_VERSION >= 18
+void File::addToThinGenerator(thinlto_code_gen_t generator, int id) {
+ assert(!_module && "Expected module to be disposed");
+ std::string pathWithID = _path;
+ pathWithID += std::to_string(id);
+ ::thinlto_codegen_add_module(generator, strdup(pathWithID.c_str()), (const char *)_content, _contentLength);
+}
+#endif
+
void File::release()
{
if ( _module != NULL )
}
#endif
-bool Parser::optimize( const std::vector<const ld::Atom*>& allAtoms,
- ld::Internal& state,
- const OptimizeOptions& options,
- ld::File::AtomHandler& handler,
- std::vector<const ld::Atom*>& newAtoms,
- std::vector<const char*>& additionalUndefines)
-{
- const bool logMustPreserve = false;
- const bool logExtraOptions = false;
- const bool logBitcodeFiles = false;
- const bool logAtomsBeforeSync = false;
- // exit quickly if nothing to do
- if ( _s_files.size() == 0 )
- return false;
-
- // print out LTO version string if -v was used
- if ( options.verbose )
- fprintf(stderr, "%s\n", ::lto_get_version());
-
- // create optimizer and add each Reader
- lto_code_gen_t generator = NULL;
-#if LTO_API_VERSION >= 11
- if ( File::sSupportsLocalContext )
- generator = ::lto_codegen_create_in_local_context();
- else
-#endif
- generator = ::lto_codegen_create();
-#if LTO_API_VERSION >= 7
- lto_codegen_set_diagnostic_handler(generator, ltoDiagnosticHandler, NULL);
-#endif
-
- // <rdar://problem/12379604> The order that files are merged must match command line order
- std::sort(_s_files.begin(), _s_files.end(), CommandLineOrderFileSorter());
- ld::File::Ordinal lastOrdinal;
-
- // When flto_codegen_only is on and we have a single .bc file, use lto_codegen_set_module instead of
- // lto_codegen_add_module, to make sure the the destination module will be the same as the input .bc file.
- bool useSetModule = false;
-#if LTO_API_VERSION >= 13
- useSetModule = (_s_files.size() == 1) && options.ltoCodegenOnly && (::lto_api_version() >= 13);
-#endif
- for (std::vector<File*>::iterator it=_s_files.begin(); it != _s_files.end(); ++it) {
- File* f = *it;
- assert(f->ordinal() > lastOrdinal);
- if ( logBitcodeFiles && !useSetModule) fprintf(stderr, "lto_codegen_add_module(%s)\n", f->path());
- if ( logBitcodeFiles && useSetModule) fprintf(stderr, "lto_codegen_set_module(%s)\n", f->path());
- if ( f->mergeIntoGenerator(generator, useSetModule) )
- throwf("lto: could not merge in %s because '%s', using libLTO version '%s'", f->path(), ::lto_get_error_message(), ::lto_get_version());
- lastOrdinal = f->ordinal();
- }
-
- // add any -mllvm command line options
- for (std::vector<const char*>::const_iterator it=options.llvmOptions->begin(); it != options.llvmOptions->end(); ++it) {
- if ( logExtraOptions ) fprintf(stderr, "passing option to llvm: %s\n", *it);
- ::lto_codegen_debug_options(generator, *it);
- }
-
- // <rdar://problem/13687397> Need a way for LTO to get cpu variants (until that info is in bitcode)
- if ( options.mcpu != NULL )
- ::lto_codegen_set_cpu(generator, options.mcpu);
+/// Instruct libLTO about the list of symbols to preserve, compute deadllvmAtoms and llvmAtoms
+void Parser::setPreservedSymbols( const std::vector<const ld::Atom*>& allAtoms,
+ ld::Internal& state,
+ const OptimizeOptions& options,
+ CStringToAtom &deadllvmAtoms,
+ CStringToAtom &llvmAtoms,
+ lto_code_gen_t generator) {
+ const bool logMustPreserve = false;
- // The atom graph uses directed edges (references). Collect all references where
- // originating atom is not part of any LTO Reader. This allows optimizer to optimize an
- // external (i.e. not originated from same .o file) reference if all originating atoms are also
+ // The atom graph uses directed edges (references). Collect all references where
+ // originating atom is not part of any LTO Reader. This allows optimizer to optimize an
+ // external (i.e. not originated from same .o file) reference if all originating atoms are also
// defined in llvm bitcode file.
CStringSet nonLLVMRefs;
- CStringToAtom llvmAtoms;
- bool hasNonllvmAtoms = false;
+ bool hasNonllvmAtoms = false;
for (std::vector<const ld::Atom*>::const_iterator it = allAtoms.begin(); it != allAtoms.end(); ++it) {
const ld::Atom* atom = *it;
- // only look at references that come from an atom that is not an llvm atom
- if ( atom->contentType() != ld::Atom::typeLTOtemporary ) {
+ // only look at references that come from an atom that is not an LTO atom
+ if (atom->contentType() != ld::Atom::typeLTOtemporary ||
+ ((lto::File *)atom->file())->isThinLTO()) {
if ( (atom->section().type() != ld::Section::typeMachHeader) && (atom->definition() != ld::Atom::definitionProxy) ) {
hasNonllvmAtoms = true;
}
switch ( fit->binding ) {
case ld::Fixup::bindingDirectlyBound:
// that reference an llvm atom
- if ( fit->u.target->contentType() == ld::Atom::typeLTOtemporary )
+ if ( fit->u.target->contentType() == ld::Atom::typeLTOtemporary )
nonLLVMRefs.insert(fit->u.target->name());
break;
case ld::Fixup::bindingsIndirectlyBound:
}
// if entry point is in a llvm bitcode file, it must be preserved by LTO
if ( state.entryPoint!= NULL ) {
- if ( state.entryPoint->contentType() == ld::Atom::typeLTOtemporary )
+ if ( state.entryPoint->contentType() == ld::Atom::typeLTOtemporary )
nonLLVMRefs.insert(state.entryPoint->name());
}
-
+
// deadAtoms are the atoms that the linker coalesced. For instance weak or tentative definitions
// overriden by another atom. If any of these deadAtoms are llvm atoms and they were replaced
- // with a mach-o atom, we need to tell the lto engine to preserve (not optimize away) its dead
+ // with a mach-o atom, we need to tell the lto engine to preserve (not optimize away) its dead
// atom so that the linker can replace it with the mach-o one later.
- CStringToAtom deadllvmAtoms;
for (std::vector<const ld::Atom*>::const_iterator it = allAtoms.begin(); it != allAtoms.end(); ++it) {
const ld::Atom* atom = *it;
if ( atom->coalescedAway() && (atom->contentType() == ld::Atom::typeLTOtemporary) ) {
if ( llvmAtom->coalescedAway() ) {
const char* name = llvmAtom->name();
if ( deadllvmAtoms.find(name) == deadllvmAtoms.end() ) {
- if ( logMustPreserve )
+ if ( logMustPreserve )
fprintf(stderr, "lto_codegen_add_must_preserve_symbol(%s) because linker coalesce away and replace with a mach-o atom\n", name);
::lto_codegen_add_must_preserve_symbol(generator, name);
deadllvmAtoms[name] = (Atom*)llvmAtom;
}
}
}
-
+
// tell code generator about symbols that must be preserved
for (CStringToAtom::iterator it = llvmAtoms.begin(); it != llvmAtoms.end(); ++it) {
const char* name = it->first;
// 1 - atom scope is global (and not linkage unit).
// 2 - included in nonLLVMRefs set.
// If a symbol is not listed in exportList then LTO is free to optimize it away.
- if ( (atom->scope() == ld::Atom::scopeGlobal) && options.preserveAllGlobals ) {
+ if ( (atom->scope() == ld::Atom::scopeGlobal) && options.preserveAllGlobals ) {
if ( logMustPreserve ) fprintf(stderr, "lto_codegen_add_must_preserve_symbol(%s) because global symbol\n", name);
::lto_codegen_add_must_preserve_symbol(generator, name);
}
::lto_codegen_add_must_preserve_symbol(generator, name);
}
}
-
+
// <rdar://problem/16165191> tell code generator to preserve initial undefines
for( std::vector<const char*>::const_iterator it=options.initialUndefines->begin(); it != options.initialUndefines->end(); ++it) {
if ( logMustPreserve ) fprintf(stderr, "lto_codegen_add_must_preserve_symbol(%s) because it is an initial undefine\n", *it);
::lto_codegen_add_must_preserve_symbol(generator, *it);
}
- // special case running ld -r on all bitcode files to produce another bitcode file (instead of mach-o)
- if ( options.relocatable && !hasNonllvmAtoms ) {
+ // special case running ld -r on all bitcode files to produce another bitcode file (instead of mach-o)
+ if ( options.relocatable && !hasNonllvmAtoms ) {
#if LTO_API_VERSION >= 15
::lto_codegen_set_should_embed_uselists(generator, false);
#endif
exit(0);
}
warning("could not produce merged bitcode file");
- }
-
- // set code-gen model
- lto_codegen_model model = LTO_CODEGEN_PIC_MODEL_DYNAMIC;
+ }
+
+}
+
+// Retrieve the codegen model from the options
+static lto_codegen_model getCodeModel(const OptimizeOptions& options) {
if ( options.mainExecutable ) {
if ( options.staticExecutable ) {
// x86_64 "static" or any "-static -pie" is really dynamic code model
if ( (options.arch == CPU_TYPE_X86_64) || options.pie )
- model = LTO_CODEGEN_PIC_MODEL_DYNAMIC;
+ return LTO_CODEGEN_PIC_MODEL_DYNAMIC;
else
- model = LTO_CODEGEN_PIC_MODEL_STATIC;
+ return LTO_CODEGEN_PIC_MODEL_STATIC;
+ }
+ else if ( options.preload ) {
+ if ( options.pie )
+ return LTO_CODEGEN_PIC_MODEL_DYNAMIC;
+ else
+ return LTO_CODEGEN_PIC_MODEL_STATIC;
}
else {
if ( options.pie )
- model = LTO_CODEGEN_PIC_MODEL_DYNAMIC;
+ return LTO_CODEGEN_PIC_MODEL_DYNAMIC;
else
- model = LTO_CODEGEN_PIC_MODEL_DYNAMIC_NO_PIC;
+ return LTO_CODEGEN_PIC_MODEL_DYNAMIC_NO_PIC;
}
}
else {
if ( options.allowTextRelocs )
- model = LTO_CODEGEN_PIC_MODEL_DYNAMIC_NO_PIC;
+ return LTO_CODEGEN_PIC_MODEL_DYNAMIC_NO_PIC;
else
- model = LTO_CODEGEN_PIC_MODEL_DYNAMIC;
+ return LTO_CODEGEN_PIC_MODEL_DYNAMIC;
}
- if ( ::lto_codegen_set_pic_model(generator, model) )
+
+}
+
+std::tuple<uint8_t *, size_t> Parser::codegen(const OptimizeOptions& options,
+ ld::Internal& state,
+ lto_code_gen_t generator,
+ std::string& object_path) {
+ uint8_t *machOFile;
+ size_t machOFileLen;
+
+ if ( ::lto_codegen_set_pic_model(generator, getCodeModel(options)) )
throwf("could not create set codegen model: %s", lto_get_error_message());
- // if requested, save off merged bitcode file
- if ( options.saveTemps ) {
- char tempBitcodePath[MAXPATHLEN];
- strcpy(tempBitcodePath, options.outputFilePath);
- strcat(tempBitcodePath, ".lto.bc");
+ // if requested, save off merged bitcode file
+ if ( options.saveTemps ) {
+ char tempBitcodePath[MAXPATHLEN];
+ strcpy(tempBitcodePath, options.outputFilePath);
+ strcat(tempBitcodePath, ".lto.bc");
#if LTO_API_VERSION >= 15
- ::lto_codegen_set_should_embed_uselists(generator, true);
+ ::lto_codegen_set_should_embed_uselists(generator, true);
#endif
- ::lto_codegen_write_merged_modules(generator, tempBitcodePath);
- }
+ ::lto_codegen_write_merged_modules(generator, tempBitcodePath);
+ }
#if LTO_API_VERSION >= 3
// find assembler next to linker
useSplitAPI = true;
#endif
- size_t machOFileLen = 0;
- const uint8_t* machOFile = NULL;
if ( useSplitAPI) {
#if LTO_API_VERSION >= 12
#if LTO_API_VERSION >= 14
- if ( ::lto_api_version() >= 14 && options.ltoCodegenOnly)
- lto_codegen_set_should_internalize(generator, false);
+ if ( ::lto_api_version() >= 14 && options.ltoCodegenOnly)
+ lto_codegen_set_should_internalize(generator, false);
#endif
// run optimizer
if ( !options.ltoCodegenOnly && ::lto_codegen_optimize(generator) )
#endif
::lto_codegen_write_merged_modules(generator, tempOptBitcodePath);
if ( options.bitcodeBundle )
- state.ltoBitcodePath = tempOptBitcodePath;
+ state.ltoBitcodePath.push_back(tempOptBitcodePath);
}
// run code generator
::lto_codegen_write_merged_modules(generator, tempOptBitcodePath);
}
}
-
- // if requested, save off temp mach-o file
- if ( options.saveTemps ) {
- char tempMachoPath[MAXPATHLEN];
- strcpy(tempMachoPath, options.outputFilePath);
- strcat(tempMachoPath, ".lto.o");
- int fd = ::open(tempMachoPath, O_CREAT | O_WRONLY | O_TRUNC, 0666);
+
+ // if requested, save off temp mach-o file
+ if ( options.saveTemps ) {
+ char tempMachoPath[MAXPATHLEN];
+ strcpy(tempMachoPath, options.outputFilePath);
+ strcat(tempMachoPath, ".lto.o");
+ int fd = ::open(tempMachoPath, O_CREAT | O_WRONLY | O_TRUNC, 0666);
if ( fd != -1) {
::write(fd, machOFile, machOFileLen);
::close(fd);
}
// if needed, save temp mach-o file to specific location
- if ( options.tmpObjectFilePath != NULL ) {
- int fd = ::open(options.tmpObjectFilePath, O_CREAT | O_WRONLY | O_TRUNC, 0666);
+ if ( !object_path.empty() ) {
+ int fd = ::open(object_path.c_str(), O_CREAT | O_WRONLY | O_TRUNC, 0666);
if ( fd != -1) {
::write(fd, machOFile, machOFileLen);
::close(fd);
}
else {
- warning("could not write LTO temp file '%s', errno=%d", options.tmpObjectFilePath, errno);
+ warning("could not write LTO temp file '%s', errno=%d", object_path.c_str(), errno);
}
}
-
- // parse generated mach-o file into a MachOReader
- ld::relocatable::File* machoFile = parseMachOFile(machOFile, machOFileLen, options);
-
+ return std::make_tuple(machOFile, machOFileLen);
+}
+
+/// Load the MachO located in buffer \p machOFile with size \p machOFileLen.
+/// The loaded atoms are sync'ed using all the supplied lists.
+void Parser::loadMachO(ld::relocatable::File* machoFile,
+ const OptimizeOptions& options,
+ ld::File::AtomHandler& handler,
+ std::vector<const ld::Atom*>& newAtoms,
+ std::vector<const char*>& additionalUndefines,
+ CStringToAtom &llvmAtoms,
+ CStringToAtom &deadllvmAtoms) {
+ const bool logAtomsBeforeSync = false;
+
// sync generated mach-o atoms with existing atoms ld knows about
if ( logAtomsBeforeSync ) {
fprintf(stderr, "llvmAtoms:\n");
}
AtomSyncer syncer(additionalUndefines, newAtoms, llvmAtoms, deadllvmAtoms, options);
machoFile->forEachAtom(syncer);
-
- // Remove InternalAtoms from ld
- for (std::vector<File*>::iterator it=_s_files.begin(); it != _s_files.end(); ++it) {
- (*it)->internalAtom().setCoalescedAway();
+
+ // notify about file level attributes
+ handler.doFile(*machoFile);
+}
+
+// Full LTO processing
+bool Parser::optimizeLTO(const std::vector<File*> files,
+ const std::vector<const ld::Atom*>& allAtoms,
+ ld::Internal& state,
+ const OptimizeOptions& options,
+ ld::File::AtomHandler& handler,
+ std::vector<const ld::Atom*>& newAtoms,
+ std::vector<const char*>& additionalUndefines) {
+ const bool logExtraOptions = false;
+ const bool logBitcodeFiles = false;
+
+ if (files.empty())
+ return true;
+
+ // create optimizer and add each Reader
+ lto_code_gen_t generator = NULL;
+#if LTO_API_VERSION >= 11
+ if ( File::sSupportsLocalContext )
+ generator = ::lto_codegen_create_in_local_context();
+ else
+#endif
+ generator = ::lto_codegen_create();
+#if LTO_API_VERSION >= 7
+ lto_codegen_set_diagnostic_handler(generator, ltoDiagnosticHandler, NULL);
+#endif
+
+ ld::File::Ordinal lastOrdinal;
+
+ // When flto_codegen_only is on and we have a single .bc file, use lto_codegen_set_module instead of
+ // lto_codegen_add_module, to make sure the the destination module will be the same as the input .bc file.
+ bool useSetModule = false;
+#if LTO_API_VERSION >= 13
+ useSetModule = (files.size() == 1) && options.ltoCodegenOnly && (::lto_api_version() >= 13);
+#endif
+ for (auto *f : files) {
+ assert(f->ordinal() > lastOrdinal);
+ if ( logBitcodeFiles && !useSetModule ) fprintf(stderr, "lto_codegen_add_module(%s)\n", f->path());
+ if ( logBitcodeFiles && useSetModule ) fprintf(stderr, "lto_codegen_set_module(%s)\n", f->path());
+ if ( f->mergeIntoGenerator(generator, useSetModule) )
+ throwf("lto: could not merge in %s because '%s', using libLTO version '%s'", f->path(), ::lto_get_error_message(), ::lto_get_version());
+ lastOrdinal = f->ordinal();
+ }
+
+ // add any -mllvm command line options
+ if ( !_s_llvmOptionsProcessed ) {
+ for (const char* opt : *options.llvmOptions) {
+ if ( logExtraOptions ) fprintf(stderr, "passing option to llvm: %s\n", opt);
+ ::lto_codegen_debug_options(generator, opt);
+ }
+ _s_llvmOptionsProcessed = true;
+ }
+
+ // <rdar://problem/13687397> Need a way for LTO to get cpu variants (until that info is in bitcode)
+ if ( options.mcpu != NULL )
+ ::lto_codegen_set_cpu(generator, options.mcpu);
+
+ // Compute the preserved symbols
+ CStringToAtom deadllvmAtoms, llvmAtoms;
+ setPreservedSymbols(allAtoms, state, options, deadllvmAtoms, llvmAtoms, generator);
+
+ size_t machOFileLen = 0;
+ const uint8_t* machOFile = NULL;
+
+ // mach-o parsing is done in-memory, but need path for debug notes
+ std::string object_path;
+ if ( options.tmpObjectFilePath != NULL ) {
+ object_path = options.tmpObjectFilePath;
+ // If the path exists and is a directory (for instance if some files
+ // were processed with ThinLTO before), we create the LTO file inside
+ // the directory.
+ struct stat statBuffer;
+ if( stat(object_path.c_str(), &statBuffer) == 0 && S_ISDIR(statBuffer.st_mode) ) {
+ object_path += "/lto.o";
+ }
}
+
+ // Codegen Now
+ std::tie(machOFile, machOFileLen) = codegen(options, state, generator, object_path);
+
+ // parse generated mach-o file into a MachOReader
+ ld::relocatable::File* machoFile = parseMachOFile(machOFile, machOFileLen, object_path, options, ld::File::Ordinal::LTOOrdinal());
+
+ // Load the generated MachO file
+ loadMachO(machoFile, options, handler, newAtoms, additionalUndefines, llvmAtoms, deadllvmAtoms);
+
// Remove Atoms from ld if code generator optimized them away
for (CStringToAtom::iterator li = llvmAtoms.begin(), le = llvmAtoms.end(); li != le; ++li) {
// check if setRealAtom() called on this Atom
li->second->setCoalescedAway();
}
}
-
- // notify about file level attributes
- handler.doFile(*machoFile);
-
+
// if final mach-o file has debug info, update original bitcode files to match
- for (std::vector<File*>::iterator it=_s_files.begin(); it != _s_files.end(); ++it) {
- (*it)->setDebugInfo(machoFile->debugInfo(), machoFile->path(),
- machoFile->modificationTime(), machoFile->cpuSubType());
+ for (auto *f : files) {
+ f->setDebugInfo(machoFile->debugInfo(), machoFile->path(), machoFile->modificationTime(), machoFile->cpuSubType());
}
-
+
+ return true;
+}
+
+#if LTO_API_VERSION >= 18
+// Create the ThinLTO codegenerator
+thinlto_code_gen_t Parser::init_thinlto_codegen(const std::vector<File*>& files,
+ const std::vector<const ld::Atom*>& allAtoms,
+ ld::Internal& state,
+ const OptimizeOptions& options,
+ CStringToAtom& deadllvmAtoms,
+ CStringToAtom& llvmAtoms) {
+ const bool logMustPreserve = false;
+
+ thinlto_code_gen_t thingenerator = ::thinlto_create_codegen();
+
+ // Caching control
+ if (options.ltoCachePath && !options.bitcodeBundle) {
+ struct stat statBuffer;
+ if( stat(options.ltoCachePath, &statBuffer) != 0 || !S_ISDIR(statBuffer.st_mode) ) {
+ if ( mkdir(options.ltoCachePath, 0700) !=0 ) {
+ warning("unable to create ThinLTO cache directory: %s", options.ltoCachePath);
+ }
+ }
+ thinlto_codegen_set_cache_dir(thingenerator, options.ltoCachePath);
+ thinlto_codegen_set_cache_pruning_interval(thingenerator, options.ltoPruneInterval);
+ thinlto_codegen_set_cache_entry_expiration(thingenerator, options.ltoPruneAfter);
+ thinlto_codegen_set_final_cache_size_relative_to_available_space(thingenerator, options.ltoMaxCacheSize);
+ }
+
+ // if requested, ask the code generator to save off intermediate bitcode files
+ if ( options.saveTemps ) {
+ std::string tempPath = options.outputFilePath;
+ tempPath += ".thinlto.bcs/";
+ struct stat statBuffer;
+ if( stat(tempPath.c_str(), &statBuffer) != 0 || !S_ISDIR(statBuffer.st_mode) ) {
+ if ( mkdir(tempPath.c_str(), 0700) !=0 ) {
+ warning("unable to create ThinLTO output directory for temporary bitcode files: %s", tempPath.c_str());
+ }
+ }
+ thinlto_codegen_set_savetemps_dir(thingenerator, tempPath.c_str());
+ }
+
+ // Set some codegen options
+ if ( thinlto_codegen_set_pic_model(thingenerator, getCodeModel(options)) )
+ throwf("could not create set codegen model: %s", lto_get_error_message());
+
+ // Expose reachability informations for internalization in LTO
+
+ // The atom graph uses directed edges (references). Collect all references where
+ // originating atom is not part of any LTO Reader. This allows optimizer to optimize an
+ // external (i.e. not originated from same .o file) reference if all originating atoms are also
+ // defined in llvm bitcode file.
+ CStringSet nonLLVMRefs;
+ CStringSet LLVMRefs;
+ for (std::vector<const ld::Atom*>::const_iterator it = allAtoms.begin(); it != allAtoms.end(); ++it) {
+ const ld::Atom* atom = *it;
+ const ld::Atom* target;
+ for (ld::Fixup::iterator fit=atom->fixupsBegin(); fit != atom->fixupsEnd(); ++fit) {
+ switch ( fit->binding ) {
+ case ld::Fixup::bindingDirectlyBound:
+ // that reference a ThinLTO llvm atom
+ target = fit->u.target;
+ if ( target->contentType() == ld::Atom::typeLTOtemporary &&
+ ((lto::File *)target->file())->isThinLTO() &&
+ atom->file() != target->file()
+ ) {
+ if (atom->contentType() != ld::Atom::typeLTOtemporary ||
+ !((lto::File *)atom->file())->isThinLTO())
+ nonLLVMRefs.insert(target->name());
+ else
+ LLVMRefs.insert(target->name());
+ if ( logMustPreserve )
+ fprintf(stderr, "Found a reference from %s -> %s\n", atom->name(), target->name());
+ }
+ break;
+ case ld::Fixup::bindingsIndirectlyBound:
+ target = state.indirectBindingTable[fit->u.bindingIndex];
+ if ( (target != NULL) && (target->contentType() == ld::Atom::typeLTOtemporary) &&
+ ((lto::File *)target->file())->isThinLTO() &&
+ atom->file() != target->file()
+ ) {
+ if (atom->contentType() != ld::Atom::typeLTOtemporary ||
+ !((lto::File *)atom->file())->isThinLTO())
+ nonLLVMRefs.insert(target->name());
+ else
+ LLVMRefs.insert(target->name());
+ if ( logMustPreserve )
+ fprintf(stderr, "Found a reference from %s -> %s\n", atom->name(), target->name());
+ }
+ default:
+ break;
+ }
+ }
+ if (atom->contentType() == ld::Atom::typeLTOtemporary &&
+ ((lto::File *)atom->file())->isThinLTO()) {
+ llvmAtoms[atom->name()] = (Atom*)atom;
+ }
+ }
+ // if entry point is in a llvm bitcode file, it must be preserved by LTO
+ if ( state.entryPoint != NULL ) {
+ if ( state.entryPoint->contentType() == ld::Atom::typeLTOtemporary )
+ nonLLVMRefs.insert(state.entryPoint->name());
+ }
+ for (auto file : files) {
+ for(uint32_t i=0; i < file->_atomArrayCount; ++i) {
+ Atom* llvmAtom = &file->_atomArray[i];
+ if ( llvmAtom->coalescedAway() ) {
+ const char* name = llvmAtom->name();
+ if ( deadllvmAtoms.find(name) == deadllvmAtoms.end() ) {
+ if ( logMustPreserve )
+ fprintf(stderr, "thinlto_codegen_add_must_preserve_symbol(%s) because linker coalesce away and replace with a mach-o atom\n", name);
+ ::thinlto_codegen_add_must_preserve_symbol(thingenerator, name, strlen(name));
+ deadllvmAtoms[name] = (Atom*)llvmAtom;
+ }
+ }
+ else if ( options.linkerDeadStripping && !llvmAtom->live() ) {
+ const char* name = llvmAtom->name();
+ deadllvmAtoms[name] = (Atom*)llvmAtom;
+ }
+ }
+ }
+
+ // tell code generator about symbols that must be preserved
+ for (CStringToAtom::iterator it = llvmAtoms.begin(); it != llvmAtoms.end(); ++it) {
+ const char* name = it->first;
+ Atom* atom = it->second;
+ // Include llvm Symbol in export list if it meets one of following two conditions
+ // 1 - atom scope is global (and not linkage unit).
+ // 2 - included in nonLLVMRefs set.
+ // If a symbol is not listed in exportList then LTO is free to optimize it away.
+ if ( (atom->scope() == ld::Atom::scopeGlobal) && options.preserveAllGlobals ) {
+ if ( logMustPreserve ) fprintf(stderr, "thinlto_codegen_add_must_preserve_symbol(%s) because global symbol\n", name);
+ ::thinlto_codegen_add_must_preserve_symbol(thingenerator, name, strlen(name));
+ }
+ else if ( nonLLVMRefs.find(name) != nonLLVMRefs.end() ) {
+ if ( logMustPreserve ) fprintf(stderr, "thinlto_codegen_add_must_preserve_symbol(%s) because referenced from outside of ThinLTO\n", name);
+ ::thinlto_codegen_add_must_preserve_symbol(thingenerator, name, strlen(name));
+ }
+ else if ( LLVMRefs.find(name) != LLVMRefs.end() ) {
+ if ( logMustPreserve ) fprintf(stderr, "thinlto_codegen_add_cross_referenced_symbol(%s) because referenced from another file\n", name);
+ ::thinlto_codegen_add_cross_referenced_symbol(thingenerator, name, strlen(name));
+ } else {
+ if ( logMustPreserve ) fprintf(stderr, "NOT preserving(%s)\n", name);
+ }
+// FIXME: to be implemented
+// else if ( options.relocatable && hasNonllvmAtoms ) {
+// // <rdar://problem/14334895> ld -r mode but merging in some mach-o files, so need to keep libLTO from optimizing away anything
+// if ( logMustPreserve ) fprintf(stderr, "lto_codegen_add_must_preserve_symbol(%s) because -r mode disable LTO dead stripping\n", name);
+// ::thinlto_codegen_add_must_preserve_symbol(thingenerator, name, strlen(name));
+// }
+ }
+
+ return thingenerator;
+}
+#endif
+
+// Full LTO processing
+bool Parser::optimizeThinLTO(const std::vector<File*>& files,
+ const std::vector<const ld::Atom*>& allAtoms,
+ ld::Internal& state,
+ const OptimizeOptions& options,
+ ld::File::AtomHandler& handler,
+ std::vector<const ld::Atom*>& newAtoms,
+ std::vector<const char*>& additionalUndefines) {
+ const bool logBitcodeFiles = false;
+
+ if (files.empty())
+ return true;
+
+#if LTO_API_VERSION >= 18
+
+ if (::lto_api_version() < 18)
+ throwf("lto: could not use -thinlto because libLTO is too old (version '%d', >=18 is required)", ::lto_api_version());
+
+ // Handle -mllvm options
+ if ( !_s_llvmOptionsProcessed ) {
+ thinlto_debug_options(options.llvmOptions->data(), options.llvmOptions->size());
+ _s_llvmOptionsProcessed = true;
+ }
+
+ // Create the ThinLTO codegenerator
+ CStringToAtom deadllvmAtoms;
+ CStringToAtom llvmAtoms;
+ thinlto_code_gen_t thingenerator = init_thinlto_codegen(files, allAtoms, state, options, deadllvmAtoms, llvmAtoms);
+
+
+ ld::File::Ordinal lastOrdinal;
+ int FileId = 0;
+ for (auto *f : files) {
+ if ( logBitcodeFiles) fprintf(stderr, "thinlto_codegen_add_module(%s)\n", f->path());
+ f->addToThinGenerator(thingenerator, FileId++);
+ lastOrdinal = f->ordinal();
+ }
+
+#if LTO_API_VERSION >= 19
+ // In the bitcode bundle case, we first run the generator with codegen disabled
+ // and get the bitcode output. These files are added for later bundling, and a
+ // new codegenerator is setup with these as input, and the optimizer disabled.
+ if (options.bitcodeBundle) {
+ // Bitcode Bundle case
+ thinlto_codegen_disable_codegen(thingenerator, true);
+ // Process the optimizer only
+ thinlto_codegen_process(thingenerator);
+ auto numObjects = thinlto_module_get_num_objects(thingenerator);
+ // Save the codegenerator
+ thinlto_code_gen_t bitcode_generator = thingenerator;
+ // Create a new codegen generator for the codegen part.
+ thingenerator = init_thinlto_codegen(files, allAtoms, state, options, deadllvmAtoms, llvmAtoms);
+ // Disable the optimizer
+ thinlto_codegen_set_codegen_only(thingenerator, true);
+
+ // Save bitcode files for later, and add them to the codegen generator.
+ for (unsigned bufID = 0; bufID < numObjects; ++bufID) {
+ auto machOFile = thinlto_module_get_object(bitcode_generator, bufID);
+ std::string tempMachoPath = options.outputFilePath;
+ tempMachoPath += ".";
+ tempMachoPath += std::to_string(bufID);
+ tempMachoPath += ".thinlto.o.bc";
+ state.ltoBitcodePath.push_back(tempMachoPath);
+ int fd = ::open(tempMachoPath.c_str(), O_CREAT | O_WRONLY | O_TRUNC, 0666);
+ if ( fd != -1 ) {
+ ::write(fd, machOFile.Buffer, machOFile.Size);
+ ::close(fd);
+ } else {
+ throwf("unable to write temporary ThinLTO output: %s", tempMachoPath.c_str());
+ }
+
+ // Add the optimized bitcode to the codegen generator now.
+ ::thinlto_codegen_add_module(thingenerator, strdup(tempMachoPath.c_str()), (const char *)machOFile.Buffer, machOFile.Size);
+ }
+ }
+
+ if (options.ltoCodegenOnly)
+ // Disable the optimizer
+ thinlto_codegen_set_codegen_only(thingenerator, true);
+#endif
+
+ // If object_path_lto is used, we switch to a file-based API: libLTO will
+ // generate the files on disk and we'll map them on-demand.
+
+#if LTO_API_VERSION >= 21
+ bool useFileBasedAPI = (options.tmpObjectFilePath && ::lto_api_version() >= 21);
+ if ( useFileBasedAPI )
+ thinlto_set_generated_objects_dir(thingenerator, options.tmpObjectFilePath);
+#endif
+
+ // run code generator
+ thinlto_codegen_process(thingenerator);
+
+ unsigned numObjects;
+#if LTO_API_VERSION >= 21
+ if ( useFileBasedAPI )
+ numObjects = thinlto_module_get_num_object_files(thingenerator);
+ else
+#endif
+ numObjects = thinlto_module_get_num_objects(thingenerator);
+ if ( numObjects == 0 )
+ throwf("could not do ThinLTO codegen (thinlto_codegen_process didn't produce any object): '%s', using libLTO version '%s'", ::lto_get_error_message(), ::lto_get_version());
+
+ auto get_thinlto_buffer_or_load_file = [&] (unsigned ID) {
+#if LTO_API_VERSION >= 21
+ if ( useFileBasedAPI ) {
+ const char* path = thinlto_module_get_object_file(thingenerator, ID);
+ // map in whole file
+ struct stat stat_buf;
+ int fd = ::open(path, O_RDONLY, 0);
+ if ( fd == -1 )
+ throwf("can't open thinlto file '%s', errno=%d", path, errno);
+ if ( ::fstat(fd, &stat_buf) != 0 )
+ throwf("fstat thinlto file '%s' failed, errno=%d\n", path, errno);
+ size_t len = stat_buf.st_size;
+ if ( len < 20 )
+ throwf("ThinLTO file '%s' too small (length=%zu)", path, len);
+ const char* p = (const char*)::mmap(NULL, len, PROT_READ, MAP_FILE | MAP_PRIVATE, fd, 0);
+ if ( p == (const char*)(-1) )
+ throwf("can't map file, errno=%d", errno);
+ ::close(fd);
+ return LTOObjectBuffer{ p, len };
+ }
+#endif
+ return thinlto_module_get_object(thingenerator, ID);
+ };
+
+ // if requested, save off objects files
+ if ( options.saveTemps ) {
+ for (unsigned bufID = 0; bufID < numObjects; ++bufID) {
+ auto machOFile = get_thinlto_buffer_or_load_file(bufID);
+ std::string tempMachoPath = options.outputFilePath;
+ tempMachoPath += ".";
+ tempMachoPath += std::to_string(bufID);
+ tempMachoPath += ".thinlto.o";
+ int fd = ::open(tempMachoPath.c_str(), O_CREAT | O_WRONLY | O_TRUNC, 0666);
+ if ( fd != -1 ) {
+ ::write(fd, machOFile.Buffer, machOFile.Size);
+ ::close(fd);
+ }
+ else {
+ warning("unable to write temporary ThinLTO output: %s", tempMachoPath.c_str());
+ }
+ }
+ }
+
+ // mach-o parsing is done in-memory, but need path for debug notes
+ std::string macho_dirpath = "/tmp/thinlto.o";
+ if ( options.tmpObjectFilePath != NULL ) {
+ macho_dirpath = options.tmpObjectFilePath;
+ struct stat statBuffer;
+ if( stat(macho_dirpath.c_str(), &statBuffer) != 0 || !S_ISDIR(statBuffer.st_mode) ) {
+ unlink(macho_dirpath.c_str());
+ if ( mkdir(macho_dirpath.c_str(), 0700) !=0 ) {
+ warning("unable to create ThinLTO output directory for temporary object files: %s", macho_dirpath.c_str());
+ }
+ }
+ }
+
+ auto ordinal = ld::File::Ordinal::LTOOrdinal().nextFileListOrdinal();
+ for (unsigned bufID = 0; bufID < numObjects; ++bufID) {
+ auto machOFile = get_thinlto_buffer_or_load_file(bufID);
+ if (!machOFile.Size) {
+ warning("Ignoring empty buffer generated by ThinLTO");
+ continue;
+ }
+
+ // mach-o parsing is done in-memory, but need path for debug notes
+ std::string tmp_path;
+#if LTO_API_VERSION >= 21
+ if ( useFileBasedAPI ) {
+ tmp_path = thinlto_module_get_object_file(thingenerator, bufID);
+ }
+ else
+#endif
+ if ( options.tmpObjectFilePath != NULL) {
+ tmp_path = macho_dirpath + "/" + std::to_string(bufID) + ".o";
+ // if needed, save temp mach-o file to specific location
+ int fd = ::open(tmp_path.c_str(), O_CREAT | O_WRONLY | O_TRUNC, 0666);
+ if ( fd != -1) {
+ ::write(fd, (const uint8_t *)machOFile.Buffer, machOFile.Size);
+ ::close(fd);
+ }
+ else {
+ warning("could not write ThinLTO temp file '%s', errno=%d", tmp_path.c_str(), errno);
+ }
+ }
+
+ // parse generated mach-o file into a MachOReader
+ ld::relocatable::File* machoFile = parseMachOFile((const uint8_t *)machOFile.Buffer, machOFile.Size, tmp_path, options, ordinal);
+ ordinal = ordinal.nextFileListOrdinal();
+
+ // Load the generated MachO file
+ loadMachO(machoFile, options, handler, newAtoms, additionalUndefines, llvmAtoms, deadllvmAtoms);
+ }
+
+ // Remove Atoms from ld if code generator optimized them away
+ for (CStringToAtom::iterator li = llvmAtoms.begin(), le = llvmAtoms.end(); li != le; ++li) {
+ // check if setRealAtom() called on this Atom
+ if ( li->second->compiledAtom() == NULL ) {
+ //fprintf(stderr, "llvm optimized away %p %s\n", li->second, li->second->name());
+ li->second->setCoalescedAway();
+ }
+ }
+
return true;
+#else // ! (LTO_API_VERSION >= 18)
+ throwf("lto: could not use -thinlto because ld was built against a version of libLTO too old (version '%d', >=18 is required)", LTO_API_VERSION);
+#endif
+}
+
+bool Parser::optimize( const std::vector<const ld::Atom*>& allAtoms,
+ ld::Internal& state,
+ const OptimizeOptions& options,
+ ld::File::AtomHandler& handler,
+ std::vector<const ld::Atom*>& newAtoms,
+ std::vector<const char*>& additionalUndefines)
+{
+
+ // exit quickly if nothing to do
+ if ( _s_files.size() == 0 )
+ return false;
+
+ // print out LTO version string if -v was used
+ if ( options.verbose )
+ fprintf(stderr, "%s\n", ::lto_get_version());
+
+ // <rdar://problem/12379604> The order that files are merged must match command line order
+ std::sort(_s_files.begin(), _s_files.end(), CommandLineOrderFileSorter());
+
+#if LTO_API_VERSION >= 19
+ // If ltoCodegenOnly is set, we don't want to merge any bitcode files and perform FullLTO
+ // we just take the ThinLTO path (optimization will be disabled anyway).
+ if (options.ltoCodegenOnly) {
+ for (auto *file : _s_files) {
+ file->setIsThinLTO(true);
+ }
+ }
+#endif
+
+ std::vector<File *> theLTOFiles;
+ std::vector<File *> theThinLTOFiles;
+ for (auto *file : _s_files) {
+ if (file->isThinLTO()) {
+ theThinLTOFiles.push_back(file);
+ } else {
+ theLTOFiles.push_back(file);
+ }
+ }
+
+ auto result = optimizeThinLTO(theThinLTOFiles, allAtoms, state, options, handler, newAtoms, additionalUndefines) &&
+ optimizeLTO(theLTOFiles, allAtoms, state, options, handler, newAtoms, additionalUndefines);
+
+ // Remove InternalAtoms from ld
+ for (std::vector<File*>::iterator it=_s_files.begin(); it != _s_files.end(); ++it) {
+ (*it)->internalAtom().setCoalescedAway();
+ }
+
+ return result;
}
void Parser::AtomSyncer::doAtom(const ld::Atom& machoAtom)
{
static const bool log = false;
- static const ld::Atom* lastProxiedAtom = NULL;
- static const ld::File* lastProxiedFile = NULL;
// update proxy atoms to point to real atoms and find new atoms
const char* name = machoAtom.name();
- CStringToAtom::iterator pos = _llvmAtoms.find(name);
+ CStringToAtom::const_iterator pos = _llvmAtoms.find(name);
if ( pos != _llvmAtoms.end() ) {
// turn Atom into a proxy for this mach-o atom
+ if (pos->second->scope() == ld::Atom::scopeLinkageUnit) {
+ if (log) fprintf(stderr, "demote %s to hidden after LTO\n", name);
+ (const_cast<ld::Atom*>(&machoAtom))->setScope(ld::Atom::scopeLinkageUnit);
+ }
pos->second->setCompiledAtom(machoAtom);
- lastProxiedAtom = &machoAtom;
- lastProxiedFile = pos->second->file();
+ _lastProxiedAtom = &machoAtom;
+ _lastProxiedFile = pos->second->file();
if (log) fprintf(stderr, "AtomSyncer, mach-o atom %p synced to lto atom %p (name=%s)\n", &machoAtom, pos->second, machoAtom.name());
}
else {
// an atom of this name was not in the allAtoms list the linker gave us
- if ( _deadllvmAtoms.find(name) != _deadllvmAtoms.end() ) {
+ auto llvmAtom = _deadllvmAtoms.find(name);
+ if ( llvmAtom != _deadllvmAtoms.end() ) {
// this corresponding to an atom that the linker coalesced away or marked not-live
if ( _options.linkerDeadStripping ) {
// llvm seems to want this atom and -dead_strip is enabled, so it will be deleted if not needed, so add back
- Atom* llvmAtom = _deadllvmAtoms[name];
- llvmAtom->setCompiledAtom(machoAtom);
+ llvmAtom->second->setCompiledAtom(machoAtom);
_newAtoms.push_back(&machoAtom);
- if (log) fprintf(stderr, "AtomSyncer, mach-o atom %p matches dead lto atom %p but adding back (name=%s)\n", &machoAtom, llvmAtom, machoAtom.name());
+ if (log) fprintf(stderr, "AtomSyncer, mach-o atom %p matches dead lto atom %p but adding back (name=%s)\n", &machoAtom, llvmAtom->second, machoAtom.name());
}
else {
// Don't pass it back as a new atom
- if (log) fprintf(stderr, "AtomSyncer, mach-o atom %p matches dead lto atom %p (name=%s)\n", &machoAtom, _deadllvmAtoms[name], machoAtom.name());
+ if (log) fprintf(stderr, "AtomSyncer, mach-o atom %p matches dead lto atom %p (name=%s)\n", &machoAtom, llvmAtom->second, machoAtom.name());
+ if ( llvmAtom->second->coalescedAway() ) {
+ if (log) fprintf(stderr, "AtomSyncer: dead coalesced atom %s\n", machoAtom.name());
+ // <rdar://problem/28269547>
+ // We told libLTO to keep a weak atom that will replaced by an native mach-o atom.
+ // We also need to remove any atoms directly dependent on this (FDE, LSDA).
+ for (ld::Fixup::iterator fit=machoAtom.fixupsBegin(), fend=machoAtom.fixupsEnd(); fit != fend; ++fit) {
+ switch ( fit->kind ) {
+ case ld::Fixup::kindNoneGroupSubordinate:
+ case ld::Fixup::kindNoneGroupSubordinateFDE:
+ case ld::Fixup::kindNoneGroupSubordinateLSDA:
+ assert(fit->binding == ld::Fixup::bindingDirectlyBound);
+ (const_cast<ld::Atom*>(fit->u.target))->setCoalescedAway();
+ if (log) fprintf(stderr, "AtomSyncer: mark coalesced-away subordinate atom %s\n", fit->u.target->name());
+ break;
+ default:
+ break;
+ }
+ }
+ }
}
}
else
// this is something new that lto conjured up, tell ld its new
_newAtoms.push_back(&machoAtom);
// <rdar://problem/15469363> if new static atom in same section as previous non-static atom, assign to same file as previous
- if ( (lastProxiedAtom != NULL) && (lastProxiedAtom->section() == machoAtom.section()) ) {
+ if ( (_lastProxiedAtom != NULL) && (_lastProxiedAtom->section() == machoAtom.section()) ) {
ld::Atom* ma = const_cast<ld::Atom*>(&machoAtom);
- ma->setFile(lastProxiedFile);
+ ma->setFile(_lastProxiedFile);
+ if (log) fprintf(stderr, "AtomSyncer, mach-o atom %s is proxied to %s (path=%s)\n", machoAtom.name(), _lastProxiedAtom->name(), _lastProxiedFile->path());
}
if (log) fprintf(stderr, "AtomSyncer, mach-o atom %p is totally new (name=%s)\n", &machoAtom, machoAtom.name());
}
// llvm symbol references always go through Atom proxy.
{
const char* targetName = fit->u.target->name();
- CStringToAtom::iterator post = _llvmAtoms.find(targetName);
+ CStringToAtom::const_iterator post = _llvmAtoms.find(targetName);
if ( post != _llvmAtoms.end() ) {
const ld::Atom* t = post->second;
if (log) fprintf(stderr, " updating direct reference to %p to be ref to %p: %s\n", fit->u.target, t, targetName);
return Parser::validFile(fileContent, fileLength, architecture, subarch);
}
+//
+// Used by archive reader to see if member defines a Category (for -ObjC semantics)
+//
+bool hasObjCCategory(const uint8_t* fileContent, uint64_t fileLength)
+{
+#if LTO_API_VERSION >= 20
+ // note: if run with older libLTO.dylib that does not implement
+ // lto_module_has_objc_category, the call will return 0 which is "false"
+ return lto_module_has_objc_category(fileContent, fileLength);
+#else
+ return false;
+#endif
+}
+
static ld::relocatable::File *parseImpl(
const uint8_t *fileContent, uint64_t fileLength, const char *path,
cpu_type_t architecture, cpu_subtype_t subarch, bool logAllFiles,
bool verboseOptimizationHints)
{
+ // do light weight check before acquiring lock
+ if ( fileLength < 4 )
+ return NULL;
+ if ( (fileContent[0] != 0xDE) || (fileContent[1] != 0xC0) || (fileContent[2] != 0x17) || (fileContent[3] != 0x0B) )
+ return NULL;
+
// Note: Once lto_module_create_in_local_context() and friends are thread safe
// this lock can be removed.
Mutex lock;
return ::lto_get_version();
}
+//
+// used by "ld -v" to report static version of libLTO.dylib API being compiled
+//
+unsigned int static_api_version()
+{
+ return LTO_API_VERSION;
+}
+
+//
+// used by "ld -v" to report version of libLTO.dylib being used
+//
+unsigned int runtime_api_version()
+{
+ return ::lto_api_version();
+}
+
//
// used by ld for error reporting
projects / apple / ld64.git / blobdiff