1 //===-- LTOModule.cpp - LLVM Link Time Optimizer --------------------------===//
3 // The LLVM Compiler Infrastructure
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
8 //===----------------------------------------------------------------------===//
10 // This file implements the Link Time Optimization library. This library is
11 // intended to be used by linker to optimize code at link time.
13 //===----------------------------------------------------------------------===//
15 #include "llvm/LTO/LTOModule.h"
16 #include "llvm/ADT/Triple.h"
17 #include "llvm/Bitcode/ReaderWriter.h"
18 #include "llvm/IR/Constants.h"
19 #include "llvm/IR/LLVMContext.h"
20 #include "llvm/IR/Metadata.h"
21 #include "llvm/IR/Module.h"
22 #include "llvm/MC/MCExpr.h"
23 #include "llvm/MC/MCInst.h"
24 #include "llvm/MC/MCInstrInfo.h"
25 #include "llvm/MC/MCParser/MCAsmParser.h"
26 #include "llvm/MC/MCSection.h"
27 #include "llvm/MC/MCStreamer.h"
28 #include "llvm/MC/MCSubtargetInfo.h"
29 #include "llvm/MC/MCSymbol.h"
30 #include "llvm/MC/MCTargetAsmParser.h"
31 #include "llvm/MC/SubtargetFeature.h"
32 #include "llvm/Support/CommandLine.h"
33 #include "llvm/Support/FileSystem.h"
34 #include "llvm/Support/Host.h"
35 #include "llvm/Support/MemoryBuffer.h"
36 #include "llvm/Support/Path.h"
37 #include "llvm/Support/SourceMgr.h"
38 #include "llvm/Support/TargetRegistry.h"
39 #include "llvm/Support/TargetSelect.h"
40 #include "llvm/Support/system_error.h"
41 #include "llvm/Target/TargetLowering.h"
42 #include "llvm/Target/TargetLoweringObjectFile.h"
43 #include "llvm/Target/TargetRegisterInfo.h"
44 #include "llvm/Transforms/Utils/GlobalStatus.h"
47 LTOModule::LTOModule(llvm::Module *m, llvm::TargetMachine *t)
48 : _module(m), _target(t),
49 _context(_target->getMCAsmInfo(), _target->getRegisterInfo(), &ObjFileInfo),
50 _mangler(t->getDataLayout()) {
51 ObjFileInfo.InitMCObjectFileInfo(t->getTargetTriple(),
52 t->getRelocationModel(), t->getCodeModel(),
56 /// isBitcodeFile - Returns 'true' if the file (or memory contents) is LLVM
58 bool LTOModule::isBitcodeFile(const void *mem, size_t length) {
59 return sys::fs::identify_magic(StringRef((const char *)mem, length)) ==
60 sys::fs::file_magic::bitcode;
63 bool LTOModule::isBitcodeFile(const char *path) {
64 sys::fs::file_magic type;
65 if (sys::fs::identify_magic(path, type))
67 return type == sys::fs::file_magic::bitcode;
70 /// isBitcodeFileForTarget - Returns 'true' if the file (or memory contents) is
71 /// LLVM bitcode for the specified triple.
72 bool LTOModule::isBitcodeFileForTarget(const void *mem, size_t length,
73 const char *triplePrefix) {
74 MemoryBuffer *buffer = makeBuffer(mem, length);
77 return isTargetMatch(buffer, triplePrefix);
80 bool LTOModule::isBitcodeFileForTarget(const char *path,
81 const char *triplePrefix) {
82 std::unique_ptr<MemoryBuffer> buffer;
83 if (MemoryBuffer::getFile(path, buffer))
85 return isTargetMatch(buffer.release(), triplePrefix);
88 /// isTargetMatch - Returns 'true' if the memory buffer is for the specified
90 bool LTOModule::isTargetMatch(MemoryBuffer *buffer, const char *triplePrefix) {
91 std::string Triple = getBitcodeTargetTriple(buffer, getGlobalContext());
93 return strncmp(Triple.c_str(), triplePrefix, strlen(triplePrefix)) == 0;
96 /// makeLTOModule - Create an LTOModule. N.B. These methods take ownership of
98 LTOModule *LTOModule::makeLTOModule(const char *path, TargetOptions options,
99 std::string &errMsg) {
100 std::unique_ptr<MemoryBuffer> buffer;
101 if (error_code ec = MemoryBuffer::getFile(path, buffer)) {
102 errMsg = ec.message();
105 return makeLTOModule(buffer.release(), options, errMsg);
108 LTOModule *LTOModule::makeLTOModule(int fd, const char *path,
109 size_t size, TargetOptions options,
110 std::string &errMsg) {
111 return makeLTOModule(fd, path, size, 0, options, errMsg);
114 LTOModule *LTOModule::makeLTOModule(int fd, const char *path,
117 TargetOptions options,
118 std::string &errMsg) {
119 std::unique_ptr<MemoryBuffer> buffer;
121 MemoryBuffer::getOpenFileSlice(fd, path, buffer, map_size, offset)) {
122 errMsg = ec.message();
125 return makeLTOModule(buffer.release(), options, errMsg);
128 LTOModule *LTOModule::makeLTOModule(const void *mem, size_t length,
129 TargetOptions options,
130 std::string &errMsg, StringRef path) {
131 std::unique_ptr<MemoryBuffer> buffer(makeBuffer(mem, length, path));
134 return makeLTOModule(buffer.release(), options, errMsg);
137 LTOModule *LTOModule::makeLTOModule(MemoryBuffer *buffer,
138 TargetOptions options,
139 std::string &errMsg) {
140 // parse bitcode buffer
141 ErrorOr<Module *> ModuleOrErr =
142 getLazyBitcodeModule(buffer, getGlobalContext());
143 if (error_code EC = ModuleOrErr.getError()) {
144 errMsg = EC.message();
148 std::unique_ptr<Module> m(ModuleOrErr.get());
150 std::string TripleStr = m->getTargetTriple();
151 if (TripleStr.empty())
152 TripleStr = sys::getDefaultTargetTriple();
153 llvm::Triple Triple(TripleStr);
155 // find machine architecture for this module
156 const Target *march = TargetRegistry::lookupTarget(TripleStr, errMsg);
160 // construct LTOModule, hand over ownership of module and target
161 SubtargetFeatures Features;
162 Features.getDefaultSubtargetFeatures(Triple);
163 std::string FeatureStr = Features.getString();
164 // Set a default CPU for Darwin triples.
166 if (Triple.isOSDarwin()) {
167 if (Triple.getArch() == llvm::Triple::x86_64)
169 else if (Triple.getArch() == llvm::Triple::x86)
171 else if (Triple.getArch() == llvm::Triple::arm64 ||
172 Triple.getArch() == llvm::Triple::aarch64)
176 TargetMachine *target = march->createTargetMachine(TripleStr, CPU, FeatureStr,
178 m->materializeAllPermanently();
180 LTOModule *Ret = new LTOModule(m.release(), target);
182 // We need a MCContext set up in order to get mangled names of private
183 // symbols. It is a bit odd that we need to report uses and definitions
184 // of private symbols, but it does look like ld64 expects to be informed
185 // of at least the ones with an 'l' prefix.
186 MCContext &Context = Ret->_context;
187 const TargetLoweringObjectFile &TLOF =
188 target->getTargetLowering()->getObjFileLowering();
189 const_cast<TargetLoweringObjectFile &>(TLOF).Initialize(Context, *target);
191 if (Ret->parseSymbols(errMsg)) {
196 Ret->parseMetadata();
201 /// Create a MemoryBuffer from a memory range with an optional name.
202 MemoryBuffer *LTOModule::makeBuffer(const void *mem, size_t length,
204 const char *startPtr = (const char*)mem;
205 return MemoryBuffer::getMemBuffer(StringRef(startPtr, length), name, false);
208 /// objcClassNameFromExpression - Get string that the data pointer points to.
210 LTOModule::objcClassNameFromExpression(const Constant *c, std::string &name) {
211 if (const ConstantExpr *ce = dyn_cast<ConstantExpr>(c)) {
212 Constant *op = ce->getOperand(0);
213 if (GlobalVariable *gvn = dyn_cast<GlobalVariable>(op)) {
214 Constant *cn = gvn->getInitializer();
215 if (ConstantDataArray *ca = dyn_cast<ConstantDataArray>(cn)) {
216 if (ca->isCString()) {
217 name = ".objc_class_name_" + ca->getAsCString().str();
226 /// addObjCClass - Parse i386/ppc ObjC class data structure.
227 void LTOModule::addObjCClass(const GlobalVariable *clgv) {
228 const ConstantStruct *c = dyn_cast<ConstantStruct>(clgv->getInitializer());
231 // second slot in __OBJC,__class is pointer to superclass name
232 std::string superclassName;
233 if (objcClassNameFromExpression(c->getOperand(1), superclassName)) {
234 NameAndAttributes info;
235 StringMap<NameAndAttributes>::value_type &entry =
236 _undefines.GetOrCreateValue(superclassName);
237 if (!entry.getValue().name) {
238 const char *symbolName = entry.getKey().data();
239 info.name = symbolName;
240 info.attributes = LTO_SYMBOL_DEFINITION_UNDEFINED;
241 info.isFunction = false;
243 entry.setValue(info);
247 // third slot in __OBJC,__class is pointer to class name
248 std::string className;
249 if (objcClassNameFromExpression(c->getOperand(2), className)) {
250 StringSet::value_type &entry = _defines.GetOrCreateValue(className);
253 NameAndAttributes info;
254 info.name = entry.getKey().data();
255 info.attributes = LTO_SYMBOL_PERMISSIONS_DATA |
256 LTO_SYMBOL_DEFINITION_REGULAR | LTO_SYMBOL_SCOPE_DEFAULT;
257 info.isFunction = false;
259 _symbols.push_back(info);
263 /// addObjCCategory - Parse i386/ppc ObjC category data structure.
264 void LTOModule::addObjCCategory(const GlobalVariable *clgv) {
265 const ConstantStruct *c = dyn_cast<ConstantStruct>(clgv->getInitializer());
268 // second slot in __OBJC,__category is pointer to target class name
269 std::string targetclassName;
270 if (!objcClassNameFromExpression(c->getOperand(1), targetclassName))
273 NameAndAttributes info;
274 StringMap<NameAndAttributes>::value_type &entry =
275 _undefines.GetOrCreateValue(targetclassName);
277 if (entry.getValue().name)
280 const char *symbolName = entry.getKey().data();
281 info.name = symbolName;
282 info.attributes = LTO_SYMBOL_DEFINITION_UNDEFINED;
283 info.isFunction = false;
285 entry.setValue(info);
288 /// addObjCClassRef - Parse i386/ppc ObjC class list data structure.
289 void LTOModule::addObjCClassRef(const GlobalVariable *clgv) {
290 std::string targetclassName;
291 if (!objcClassNameFromExpression(clgv->getInitializer(), targetclassName))
294 NameAndAttributes info;
295 StringMap<NameAndAttributes>::value_type &entry =
296 _undefines.GetOrCreateValue(targetclassName);
297 if (entry.getValue().name)
300 const char *symbolName = entry.getKey().data();
301 info.name = symbolName;
302 info.attributes = LTO_SYMBOL_DEFINITION_UNDEFINED;
303 info.isFunction = false;
305 entry.setValue(info);
308 /// addDefinedDataSymbol - Add a data symbol as defined to the list.
309 void LTOModule::addDefinedDataSymbol(const GlobalValue *v) {
310 // Add to list of defined symbols.
311 addDefinedSymbol(v, false);
313 if (!v->hasSection() /* || !isTargetDarwin */)
316 // Special case i386/ppc ObjC data structures in magic sections:
317 // The issue is that the old ObjC object format did some strange
318 // contortions to avoid real linker symbols. For instance, the
319 // ObjC class data structure is allocated statically in the executable
320 // that defines that class. That data structures contains a pointer to
321 // its superclass. But instead of just initializing that part of the
322 // struct to the address of its superclass, and letting the static and
323 // dynamic linkers do the rest, the runtime works by having that field
324 // instead point to a C-string that is the name of the superclass.
325 // At runtime the objc initialization updates that pointer and sets
326 // it to point to the actual super class. As far as the linker
327 // knows it is just a pointer to a string. But then someone wanted the
328 // linker to issue errors at build time if the superclass was not found.
329 // So they figured out a way in mach-o object format to use an absolute
330 // symbols (.objc_class_name_Foo = 0) and a floating reference
331 // (.reference .objc_class_name_Bar) to cause the linker into erroring when
332 // a class was missing.
333 // The following synthesizes the implicit .objc_* symbols for the linker
334 // from the ObjC data structures generated by the front end.
336 // special case if this data blob is an ObjC class definition
337 if (v->getSection().compare(0, 15, "__OBJC,__class,") == 0) {
338 if (const GlobalVariable *gv = dyn_cast<GlobalVariable>(v)) {
343 // special case if this data blob is an ObjC category definition
344 else if (v->getSection().compare(0, 18, "__OBJC,__category,") == 0) {
345 if (const GlobalVariable *gv = dyn_cast<GlobalVariable>(v)) {
350 // special case if this data blob is the list of referenced classes
351 else if (v->getSection().compare(0, 18, "__OBJC,__cls_refs,") == 0) {
352 if (const GlobalVariable *gv = dyn_cast<GlobalVariable>(v)) {
358 /// addDefinedFunctionSymbol - Add a function symbol as defined to the list.
359 void LTOModule::addDefinedFunctionSymbol(const Function *f) {
360 // add to list of defined symbols
361 addDefinedSymbol(f, true);
364 static bool canBeHidden(const GlobalValue *GV) {
365 // FIXME: this is duplicated with another static function in AsmPrinter.cpp
366 GlobalValue::LinkageTypes L = GV->getLinkage();
368 if (L != GlobalValue::LinkOnceODRLinkage)
371 if (GV->hasUnnamedAddr())
374 // If it is a non constant variable, it needs to be uniqued across shared
376 if (const GlobalVariable *Var = dyn_cast<GlobalVariable>(GV)) {
377 if (!Var->isConstant())
382 if (GlobalStatus::analyzeGlobal(GV, GS))
385 return !GS.IsCompared;
388 /// addDefinedSymbol - Add a defined symbol to the list.
389 void LTOModule::addDefinedSymbol(const GlobalValue *def, bool isFunction) {
390 // ignore all llvm.* symbols
391 if (def->getName().startswith("llvm."))
394 // string is owned by _defines
395 SmallString<64> Buffer;
396 _target->getNameWithPrefix(Buffer, def, _mangler);
398 // set alignment part log2() can have rounding errors
399 uint32_t align = def->getAlignment();
400 uint32_t attr = align ? countTrailingZeros(align) : 0;
402 // set permissions part
404 attr |= LTO_SYMBOL_PERMISSIONS_CODE;
406 const GlobalVariable *gv = dyn_cast<GlobalVariable>(def);
407 if (gv && gv->isConstant())
408 attr |= LTO_SYMBOL_PERMISSIONS_RODATA;
410 attr |= LTO_SYMBOL_PERMISSIONS_DATA;
413 // set definition part
414 if (def->hasWeakLinkage() || def->hasLinkOnceLinkage())
415 attr |= LTO_SYMBOL_DEFINITION_WEAK;
416 else if (def->hasCommonLinkage())
417 attr |= LTO_SYMBOL_DEFINITION_TENTATIVE;
419 attr |= LTO_SYMBOL_DEFINITION_REGULAR;
422 if (def->hasLocalLinkage())
423 // Ignore visibility if linkage is local.
424 attr |= LTO_SYMBOL_SCOPE_INTERNAL;
425 else if (def->hasHiddenVisibility())
426 attr |= LTO_SYMBOL_SCOPE_HIDDEN;
427 else if (def->hasProtectedVisibility())
428 attr |= LTO_SYMBOL_SCOPE_PROTECTED;
429 else if (canBeHidden(def))
430 attr |= LTO_SYMBOL_SCOPE_DEFAULT_CAN_BE_HIDDEN;
432 attr |= LTO_SYMBOL_SCOPE_DEFAULT;
434 StringSet::value_type &entry = _defines.GetOrCreateValue(Buffer);
437 // fill information structure
438 NameAndAttributes info;
439 StringRef Name = entry.getKey();
440 info.name = Name.data();
441 assert(info.name[Name.size()] == '\0');
442 info.attributes = attr;
443 info.isFunction = isFunction;
446 // add to table of symbols
447 _symbols.push_back(info);
450 /// addAsmGlobalSymbol - Add a global symbol from module-level ASM to the
452 void LTOModule::addAsmGlobalSymbol(const char *name,
453 lto_symbol_attributes scope) {
454 StringSet::value_type &entry = _defines.GetOrCreateValue(name);
456 // only add new define if not already defined
457 if (entry.getValue())
462 NameAndAttributes &info = _undefines[entry.getKey().data()];
464 if (info.symbol == nullptr) {
465 // FIXME: This is trying to take care of module ASM like this:
467 // module asm ".zerofill __FOO, __foo, _bar_baz_qux, 0"
469 // but is gross and its mother dresses it funny. Have the ASM parser give us
470 // more details for this type of situation so that we're not guessing so
473 // fill information structure
474 info.name = entry.getKey().data();
476 LTO_SYMBOL_PERMISSIONS_DATA | LTO_SYMBOL_DEFINITION_REGULAR | scope;
477 info.isFunction = false;
478 info.symbol = nullptr;
480 // add to table of symbols
481 _symbols.push_back(info);
486 addDefinedFunctionSymbol(cast<Function>(info.symbol));
488 addDefinedDataSymbol(info.symbol);
490 _symbols.back().attributes &= ~LTO_SYMBOL_SCOPE_MASK;
491 _symbols.back().attributes |= scope;
494 /// addAsmGlobalSymbolUndef - Add a global symbol from module-level ASM to the
496 void LTOModule::addAsmGlobalSymbolUndef(const char *name) {
497 StringMap<NameAndAttributes>::value_type &entry =
498 _undefines.GetOrCreateValue(name);
500 _asm_undefines.push_back(entry.getKey().data());
502 // we already have the symbol
503 if (entry.getValue().name)
506 uint32_t attr = LTO_SYMBOL_DEFINITION_UNDEFINED;
507 attr |= LTO_SYMBOL_SCOPE_DEFAULT;
508 NameAndAttributes info;
509 info.name = entry.getKey().data();
510 info.attributes = attr;
511 info.isFunction = false;
512 info.symbol = nullptr;
514 entry.setValue(info);
517 /// addPotentialUndefinedSymbol - Add a symbol which isn't defined just yet to a
518 /// list to be resolved later.
520 LTOModule::addPotentialUndefinedSymbol(const GlobalValue *decl, bool isFunc) {
521 // ignore all llvm.* symbols
522 if (decl->getName().startswith("llvm."))
525 // ignore all aliases
526 if (isa<GlobalAlias>(decl))
529 SmallString<64> name;
530 _target->getNameWithPrefix(name, decl, _mangler);
532 StringMap<NameAndAttributes>::value_type &entry =
533 _undefines.GetOrCreateValue(name);
535 // we already have the symbol
536 if (entry.getValue().name)
539 NameAndAttributes info;
541 info.name = entry.getKey().data();
543 if (decl->hasExternalWeakLinkage())
544 info.attributes = LTO_SYMBOL_DEFINITION_WEAKUNDEF;
546 info.attributes = LTO_SYMBOL_DEFINITION_UNDEFINED;
548 info.isFunction = isFunc;
551 entry.setValue(info);
556 class RecordStreamer : public MCStreamer {
558 enum State { NeverSeen, Global, Defined, DefinedGlobal, Used };
561 StringMap<State> Symbols;
563 void markDefined(const MCSymbol &Symbol) {
564 State &S = Symbols[Symbol.getName()];
577 void markGlobal(const MCSymbol &Symbol) {
578 State &S = Symbols[Symbol.getName()];
592 void markUsed(const MCSymbol &Symbol) {
593 State &S = Symbols[Symbol.getName()];
607 // FIXME: mostly copied for the obj streamer.
608 void AddValueSymbols(const MCExpr *Value) {
609 switch (Value->getKind()) {
611 // FIXME: What should we do in here?
614 case MCExpr::Constant:
617 case MCExpr::Binary: {
618 const MCBinaryExpr *BE = cast<MCBinaryExpr>(Value);
619 AddValueSymbols(BE->getLHS());
620 AddValueSymbols(BE->getRHS());
624 case MCExpr::SymbolRef:
625 markUsed(cast<MCSymbolRefExpr>(Value)->getSymbol());
629 AddValueSymbols(cast<MCUnaryExpr>(Value)->getSubExpr());
635 typedef StringMap<State>::const_iterator const_iterator;
637 const_iterator begin() {
638 return Symbols.begin();
641 const_iterator end() {
642 return Symbols.end();
645 RecordStreamer(MCContext &Context) : MCStreamer(Context) {}
647 void EmitInstruction(const MCInst &Inst,
648 const MCSubtargetInfo &STI) override {
650 for (unsigned i = Inst.getNumOperands(); i--; )
651 if (Inst.getOperand(i).isExpr())
652 AddValueSymbols(Inst.getOperand(i).getExpr());
654 void EmitLabel(MCSymbol *Symbol) override {
655 Symbol->setSection(*getCurrentSection().first);
656 markDefined(*Symbol);
658 void EmitDebugLabel(MCSymbol *Symbol) override {
661 void EmitAssignment(MCSymbol *Symbol, const MCExpr *Value) override {
662 // FIXME: should we handle aliases?
663 markDefined(*Symbol);
664 AddValueSymbols(Value);
666 bool EmitSymbolAttribute(MCSymbol *Symbol,
667 MCSymbolAttr Attribute) override {
668 if (Attribute == MCSA_Global)
672 void EmitZerofill(const MCSection *Section, MCSymbol *Symbol,
673 uint64_t Size , unsigned ByteAlignment) override {
674 markDefined(*Symbol);
676 void EmitCommonSymbol(MCSymbol *Symbol, uint64_t Size,
677 unsigned ByteAlignment) override {
678 markDefined(*Symbol);
681 void EmitBundleAlignMode(unsigned AlignPow2) override {}
682 void EmitBundleLock(bool AlignToEnd) override {}
683 void EmitBundleUnlock() override {}
686 void ChangeSection(const MCSection *Section,
687 const MCExpr *Subsection) override {}
688 void EmitAssemblerFlag(MCAssemblerFlag Flag) override {}
689 void EmitThumbFunc(MCSymbol *Func) override {}
690 void EmitSymbolDesc(MCSymbol *Symbol, unsigned DescValue) override {}
691 void EmitWeakReference(MCSymbol *Alias, const MCSymbol *Symbol) override {}
692 void BeginCOFFSymbolDef(const MCSymbol *Symbol) override {}
693 void EmitCOFFSymbolStorageClass(int StorageClass) override {}
694 void EmitCOFFSymbolType(int Type) override {}
695 void EndCOFFSymbolDef() override {}
696 void EmitELFSize(MCSymbol *Symbol, const MCExpr *Value) override {}
697 void EmitLocalCommonSymbol(MCSymbol *Symbol, uint64_t Size,
698 unsigned ByteAlignment) override {}
699 void EmitTBSSSymbol(const MCSection *Section, MCSymbol *Symbol,
700 uint64_t Size, unsigned ByteAlignment) override {}
701 void EmitBytes(StringRef Data) override {}
702 void EmitValueImpl(const MCExpr *Value, unsigned Size,
703 const SMLoc &Loc) override {}
704 void EmitULEB128Value(const MCExpr *Value) override {}
705 void EmitSLEB128Value(const MCExpr *Value) override {}
706 void EmitValueToAlignment(unsigned ByteAlignment, int64_t Value,
708 unsigned MaxBytesToEmit) override {}
709 void EmitCodeAlignment(unsigned ByteAlignment,
710 unsigned MaxBytesToEmit) override {}
711 bool EmitValueToOffset(const MCExpr *Offset,
712 unsigned char Value) override { return false; }
713 void EmitFileDirective(StringRef Filename) override {}
714 void FinishImpl() override {}
715 void EmitCFIEndProcImpl(MCDwarfFrameInfo &Frame) override {
716 RecordProcEnd(Frame);
719 } // end anonymous namespace
721 /// addAsmGlobalSymbols - Add global symbols from module-level ASM to the
722 /// defined or undefined lists.
723 bool LTOModule::addAsmGlobalSymbols(std::string &errMsg) {
724 const std::string &inlineAsm = _module->getModuleInlineAsm();
725 if (inlineAsm.empty())
728 std::unique_ptr<RecordStreamer> Streamer(new RecordStreamer(_context));
729 MemoryBuffer *Buffer = MemoryBuffer::getMemBuffer(inlineAsm);
731 SrcMgr.AddNewSourceBuffer(Buffer, SMLoc());
732 std::unique_ptr<MCAsmParser> Parser(
733 createMCAsmParser(SrcMgr, _context, *Streamer, *_target->getMCAsmInfo()));
734 const Target &T = _target->getTarget();
735 std::unique_ptr<MCInstrInfo> MCII(T.createMCInstrInfo());
736 std::unique_ptr<MCSubtargetInfo> STI(T.createMCSubtargetInfo(
737 _target->getTargetTriple(), _target->getTargetCPU(),
738 _target->getTargetFeatureString()));
739 std::unique_ptr<MCTargetAsmParser> TAP(
740 T.createMCAsmParser(*STI, *Parser.get(), *MCII,
741 _target->Options.MCOptions));
743 errMsg = "target " + std::string(T.getName()) +
744 " does not define AsmParser.";
748 Parser->setTargetParser(*TAP);
749 if (Parser->Run(false))
752 for (RecordStreamer::const_iterator i = Streamer->begin(),
753 e = Streamer->end(); i != e; ++i) {
754 StringRef Key = i->first();
755 RecordStreamer::State Value = i->second;
756 if (Value == RecordStreamer::DefinedGlobal)
757 addAsmGlobalSymbol(Key.data(), LTO_SYMBOL_SCOPE_DEFAULT);
758 else if (Value == RecordStreamer::Defined)
759 addAsmGlobalSymbol(Key.data(), LTO_SYMBOL_SCOPE_INTERNAL);
760 else if (Value == RecordStreamer::Global ||
761 Value == RecordStreamer::Used)
762 addAsmGlobalSymbolUndef(Key.data());
768 /// isDeclaration - Return 'true' if the global value is a declaration.
769 static bool isDeclaration(const GlobalValue &V) {
770 if (V.hasAvailableExternallyLinkage())
773 if (V.isMaterializable())
776 return V.isDeclaration();
779 /// parseSymbols - Parse the symbols from the module and model-level ASM and add
780 /// them to either the defined or undefined lists.
781 bool LTOModule::parseSymbols(std::string &errMsg) {
783 for (Module::iterator f = _module->begin(), e = _module->end(); f != e; ++f) {
784 if (isDeclaration(*f))
785 addPotentialUndefinedSymbol(f, true);
787 addDefinedFunctionSymbol(f);
791 for (Module::global_iterator v = _module->global_begin(),
792 e = _module->global_end(); v != e; ++v) {
793 if (isDeclaration(*v))
794 addPotentialUndefinedSymbol(v, false);
796 addDefinedDataSymbol(v);
800 if (addAsmGlobalSymbols(errMsg))
804 for (const auto &Alias : _module->aliases())
805 addDefinedDataSymbol(&Alias);
807 // make symbols for all undefines
808 for (StringMap<NameAndAttributes>::iterator u =_undefines.begin(),
809 e = _undefines.end(); u != e; ++u) {
810 // If this symbol also has a definition, then don't make an undefine because
811 // it is a tentative definition.
812 if (_defines.count(u->getKey())) continue;
813 NameAndAttributes info = u->getValue();
814 _symbols.push_back(info);
820 /// parseMetadata - Parse metadata from the module
821 void LTOModule::parseMetadata() {
823 if (Value *Val = _module->getModuleFlag("Linker Options")) {
824 MDNode *LinkerOptions = cast<MDNode>(Val);
825 for (unsigned i = 0, e = LinkerOptions->getNumOperands(); i != e; ++i) {
826 MDNode *MDOptions = cast<MDNode>(LinkerOptions->getOperand(i));
827 for (unsigned ii = 0, ie = MDOptions->getNumOperands(); ii != ie; ++ii) {
828 MDString *MDOption = cast<MDString>(MDOptions->getOperand(ii));
829 StringRef Op = _linkeropt_strings.
830 GetOrCreateValue(MDOption->getString()).getKey();
831 StringRef DepLibName = _target->getTargetLowering()->
832 getObjFileLowering().getDepLibFromLinkerOpt(Op);
833 if (!DepLibName.empty())
834 _deplibs.push_back(DepLibName.data());
835 else if (!Op.empty())
836 _linkeropts.push_back(Op.data());
841 // Add other interesting metadata here.