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diff --git a/contrib/llvm/lib/LTO/LTOModule.cpp b/contrib/llvm/lib/LTO/LTOModule.cpp
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+//===-- LTOModule.cpp - LLVM Link Time Optimizer --------------------------===//
+//
+// The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+// This file implements the Link Time Optimization library. This library is
+// intended to be used by linker to optimize code at link time.
+//
+//===----------------------------------------------------------------------===//
+
+#include "llvm/LTO/LTOModule.h"
+#include "llvm/ADT/Triple.h"
+#include "llvm/Bitcode/ReaderWriter.h"
+#include "llvm/CodeGen/Analysis.h"
+#include "llvm/IR/Constants.h"
+#include "llvm/IR/DiagnosticPrinter.h"
+#include "llvm/IR/LLVMContext.h"
+#include "llvm/IR/Metadata.h"
+#include "llvm/IR/Module.h"
+#include "llvm/MC/MCExpr.h"
+#include "llvm/MC/MCInst.h"
+#include "llvm/MC/MCInstrInfo.h"
+#include "llvm/MC/MCParser/MCAsmParser.h"
+#include "llvm/MC/MCSection.h"
+#include "llvm/MC/MCSubtargetInfo.h"
+#include "llvm/MC/MCSymbol.h"
+#include "llvm/MC/MCTargetAsmParser.h"
+#include "llvm/MC/SubtargetFeature.h"
+#include "llvm/Object/IRObjectFile.h"
+#include "llvm/Object/ObjectFile.h"
+#include "llvm/Support/CommandLine.h"
+#include "llvm/Support/FileSystem.h"
+#include "llvm/Support/Host.h"
+#include "llvm/Support/MemoryBuffer.h"
+#include "llvm/Support/Path.h"
+#include "llvm/Support/SourceMgr.h"
+#include "llvm/Support/TargetRegistry.h"
+#include "llvm/Support/TargetSelect.h"
+#include "llvm/Target/TargetLowering.h"
+#include "llvm/Target/TargetLoweringObjectFile.h"
+#include "llvm/Target/TargetRegisterInfo.h"
+#include "llvm/Target/TargetSubtargetInfo.h"
+#include "llvm/Transforms/Utils/GlobalStatus.h"
+#include <system_error>
+using namespace llvm;
+using namespace llvm::object;
+
+LTOModule::LTOModule(std::unique_ptr<object::IRObjectFile> Obj,
+ llvm::TargetMachine *TM)
+ : IRFile(std::move(Obj)), _target(TM) {}
+
+LTOModule::LTOModule(std::unique_ptr<object::IRObjectFile> Obj,
+ llvm::TargetMachine *TM,
+ std::unique_ptr<LLVMContext> Context)
+ : OwnedContext(std::move(Context)), IRFile(std::move(Obj)), _target(TM) {}
+
+LTOModule::~LTOModule() {}
+
+/// isBitcodeFile - Returns 'true' if the file (or memory contents) is LLVM
+/// bitcode.
+bool LTOModule::isBitcodeFile(const void *Mem, size_t Length) {
+ ErrorOr<MemoryBufferRef> BCData = IRObjectFile::findBitcodeInMemBuffer(
+ MemoryBufferRef(StringRef((const char *)Mem, Length), "<mem>"));
+ return bool(BCData);
+}
+
+bool LTOModule::isBitcodeFile(const char *Path) {
+ ErrorOr<std::unique_ptr<MemoryBuffer>> BufferOrErr =
+ MemoryBuffer::getFile(Path);
+ if (!BufferOrErr)
+ return false;
+
+ ErrorOr<MemoryBufferRef> BCData = IRObjectFile::findBitcodeInMemBuffer(
+ BufferOrErr.get()->getMemBufferRef());
+ return bool(BCData);
+}
+
+bool LTOModule::isBitcodeForTarget(MemoryBuffer *Buffer,
+ StringRef TriplePrefix) {
+ ErrorOr<MemoryBufferRef> BCOrErr =
+ IRObjectFile::findBitcodeInMemBuffer(Buffer->getMemBufferRef());
+ if (!BCOrErr)
+ return false;
+ LLVMContext Context;
+ std::string Triple = getBitcodeTargetTriple(*BCOrErr, Context);
+ return StringRef(Triple).startswith(TriplePrefix);
+}
+
+LTOModule *LTOModule::createFromFile(const char *path, TargetOptions options,
+ std::string &errMsg) {
+ ErrorOr<std::unique_ptr<MemoryBuffer>> BufferOrErr =
+ MemoryBuffer::getFile(path);
+ if (std::error_code EC = BufferOrErr.getError()) {
+ errMsg = EC.message();
+ return nullptr;
+ }
+ std::unique_ptr<MemoryBuffer> Buffer = std::move(BufferOrErr.get());
+ return makeLTOModule(Buffer->getMemBufferRef(), options, errMsg,
+ &getGlobalContext());
+}
+
+LTOModule *LTOModule::createFromOpenFile(int fd, const char *path, size_t size,
+ TargetOptions options,
+ std::string &errMsg) {
+ return createFromOpenFileSlice(fd, path, size, 0, options, errMsg);
+}
+
+LTOModule *LTOModule::createFromOpenFileSlice(int fd, const char *path,
+ size_t map_size, off_t offset,
+ TargetOptions options,
+ std::string &errMsg) {
+ ErrorOr<std::unique_ptr<MemoryBuffer>> BufferOrErr =
+ MemoryBuffer::getOpenFileSlice(fd, path, map_size, offset);
+ if (std::error_code EC = BufferOrErr.getError()) {
+ errMsg = EC.message();
+ return nullptr;
+ }
+ std::unique_ptr<MemoryBuffer> Buffer = std::move(BufferOrErr.get());
+ return makeLTOModule(Buffer->getMemBufferRef(), options, errMsg,
+ &getGlobalContext());
+}
+
+LTOModule *LTOModule::createFromBuffer(const void *mem, size_t length,
+ TargetOptions options,
+ std::string &errMsg, StringRef path) {
+ return createInContext(mem, length, options, errMsg, path,
+ &getGlobalContext());
+}
+
+LTOModule *LTOModule::createInLocalContext(const void *mem, size_t length,
+ TargetOptions options,
+ std::string &errMsg,
+ StringRef path) {
+ return createInContext(mem, length, options, errMsg, path, nullptr);
+}
+
+LTOModule *LTOModule::createInContext(const void *mem, size_t length,
+ TargetOptions options,
+ std::string &errMsg, StringRef path,
+ LLVMContext *Context) {
+ StringRef Data((const char *)mem, length);
+ MemoryBufferRef Buffer(Data, path);
+ return makeLTOModule(Buffer, options, errMsg, Context);
+}
+
+static Module *parseBitcodeFileImpl(MemoryBufferRef Buffer,
+ LLVMContext &Context, bool ShouldBeLazy,
+ std::string &ErrMsg) {
+
+ // Find the buffer.
+ ErrorOr<MemoryBufferRef> MBOrErr =
+ IRObjectFile::findBitcodeInMemBuffer(Buffer);
+ if (std::error_code EC = MBOrErr.getError()) {
+ ErrMsg = EC.message();
+ return nullptr;
+ }
+
+ std::function<void(const DiagnosticInfo &)> DiagnosticHandler =
+ [&ErrMsg](const DiagnosticInfo &DI) {
+ raw_string_ostream Stream(ErrMsg);
+ DiagnosticPrinterRawOStream DP(Stream);
+ DI.print(DP);
+ };
+
+ if (!ShouldBeLazy) {
+ // Parse the full file.
+ ErrorOr<Module *> M =
+ parseBitcodeFile(*MBOrErr, Context, DiagnosticHandler);
+ if (!M)
+ return nullptr;
+ return *M;
+ }
+
+ // Parse lazily.
+ std::unique_ptr<MemoryBuffer> LightweightBuf =
+ MemoryBuffer::getMemBuffer(*MBOrErr, false);
+ ErrorOr<Module *> M = getLazyBitcodeModule(std::move(LightweightBuf), Context,
+ DiagnosticHandler);
+ if (!M)
+ return nullptr;
+ return *M;
+}
+
+LTOModule *LTOModule::makeLTOModule(MemoryBufferRef Buffer,
+ TargetOptions options, std::string &errMsg,
+ LLVMContext *Context) {
+ std::unique_ptr<LLVMContext> OwnedContext;
+ if (!Context) {
+ OwnedContext = llvm::make_unique<LLVMContext>();
+ Context = OwnedContext.get();
+ }
+
+ // If we own a context, we know this is being used only for symbol
+ // extraction, not linking. Be lazy in that case.
+ std::unique_ptr<Module> M(parseBitcodeFileImpl(
+ Buffer, *Context,
+ /* ShouldBeLazy */ static_cast<bool>(OwnedContext), errMsg));
+ if (!M)
+ return nullptr;
+
+ std::string TripleStr = M->getTargetTriple();
+ if (TripleStr.empty())
+ TripleStr = sys::getDefaultTargetTriple();
+ llvm::Triple Triple(TripleStr);
+
+ // find machine architecture for this module
+ const Target *march = TargetRegistry::lookupTarget(TripleStr, errMsg);
+ if (!march)
+ return nullptr;
+
+ // construct LTOModule, hand over ownership of module and target
+ SubtargetFeatures Features;
+ Features.getDefaultSubtargetFeatures(Triple);
+ std::string FeatureStr = Features.getString();
+ // Set a default CPU for Darwin triples.
+ std::string CPU;
+ if (Triple.isOSDarwin()) {
+ if (Triple.getArch() == llvm::Triple::x86_64)
+ CPU = "core2";
+ else if (Triple.getArch() == llvm::Triple::x86)
+ CPU = "yonah";
+ else if (Triple.getArch() == llvm::Triple::aarch64)
+ CPU = "cyclone";
+ }
+
+ TargetMachine *target = march->createTargetMachine(TripleStr, CPU, FeatureStr,
+ options);
+ M->setDataLayout(target->getSubtargetImpl()->getDataLayout());
+
+ std::unique_ptr<object::IRObjectFile> IRObj(
+ new object::IRObjectFile(Buffer, std::move(M)));
+
+ LTOModule *Ret;
+ if (OwnedContext)
+ Ret = new LTOModule(std::move(IRObj), target, std::move(OwnedContext));
+ else
+ Ret = new LTOModule(std::move(IRObj), target);
+
+ if (Ret->parseSymbols(errMsg)) {
+ delete Ret;
+ return nullptr;
+ }
+
+ Ret->parseMetadata();
+
+ return Ret;
+}
+
+/// Create a MemoryBuffer from a memory range with an optional name.
+std::unique_ptr<MemoryBuffer>
+LTOModule::makeBuffer(const void *mem, size_t length, StringRef name) {
+ const char *startPtr = (const char*)mem;
+ return MemoryBuffer::getMemBuffer(StringRef(startPtr, length), name, false);
+}
+
+/// objcClassNameFromExpression - Get string that the data pointer points to.
+bool
+LTOModule::objcClassNameFromExpression(const Constant *c, std::string &name) {
+ if (const ConstantExpr *ce = dyn_cast<ConstantExpr>(c)) {
+ Constant *op = ce->getOperand(0);
+ if (GlobalVariable *gvn = dyn_cast<GlobalVariable>(op)) {
+ Constant *cn = gvn->getInitializer();
+ if (ConstantDataArray *ca = dyn_cast<ConstantDataArray>(cn)) {
+ if (ca->isCString()) {
+ name = ".objc_class_name_" + ca->getAsCString().str();
+ return true;
+ }
+ }
+ }
+ }
+ return false;
+}
+
+/// addObjCClass - Parse i386/ppc ObjC class data structure.
+void LTOModule::addObjCClass(const GlobalVariable *clgv) {
+ const ConstantStruct *c = dyn_cast<ConstantStruct>(clgv->getInitializer());
+ if (!c) return;
+
+ // second slot in __OBJC,__class is pointer to superclass name
+ std::string superclassName;
+ if (objcClassNameFromExpression(c->getOperand(1), superclassName)) {
+ auto IterBool =
+ _undefines.insert(std::make_pair(superclassName, NameAndAttributes()));
+ if (IterBool.second) {
+ NameAndAttributes &info = IterBool.first->second;
+ info.name = IterBool.first->first().data();
+ info.attributes = LTO_SYMBOL_DEFINITION_UNDEFINED;
+ info.isFunction = false;
+ info.symbol = clgv;
+ }
+ }
+
+ // third slot in __OBJC,__class is pointer to class name
+ std::string className;
+ if (objcClassNameFromExpression(c->getOperand(2), className)) {
+ auto Iter = _defines.insert(className).first;
+
+ NameAndAttributes info;
+ info.name = Iter->first().data();
+ info.attributes = LTO_SYMBOL_PERMISSIONS_DATA |
+ LTO_SYMBOL_DEFINITION_REGULAR | LTO_SYMBOL_SCOPE_DEFAULT;
+ info.isFunction = false;
+ info.symbol = clgv;
+ _symbols.push_back(info);
+ }
+}
+
+/// addObjCCategory - Parse i386/ppc ObjC category data structure.
+void LTOModule::addObjCCategory(const GlobalVariable *clgv) {
+ const ConstantStruct *c = dyn_cast<ConstantStruct>(clgv->getInitializer());
+ if (!c) return;
+
+ // second slot in __OBJC,__category is pointer to target class name
+ std::string targetclassName;
+ if (!objcClassNameFromExpression(c->getOperand(1), targetclassName))
+ return;
+
+ auto IterBool =
+ _undefines.insert(std::make_pair(targetclassName, NameAndAttributes()));
+
+ if (!IterBool.second)
+ return;
+
+ NameAndAttributes &info = IterBool.first->second;
+ info.name = IterBool.first->first().data();
+ info.attributes = LTO_SYMBOL_DEFINITION_UNDEFINED;
+ info.isFunction = false;
+ info.symbol = clgv;
+}
+
+/// addObjCClassRef - Parse i386/ppc ObjC class list data structure.
+void LTOModule::addObjCClassRef(const GlobalVariable *clgv) {
+ std::string targetclassName;
+ if (!objcClassNameFromExpression(clgv->getInitializer(), targetclassName))
+ return;
+
+ auto IterBool =
+ _undefines.insert(std::make_pair(targetclassName, NameAndAttributes()));
+
+ if (!IterBool.second)
+ return;
+
+ NameAndAttributes &info = IterBool.first->second;
+ info.name = IterBool.first->first().data();
+ info.attributes = LTO_SYMBOL_DEFINITION_UNDEFINED;
+ info.isFunction = false;
+ info.symbol = clgv;
+}
+
+void LTOModule::addDefinedDataSymbol(const object::BasicSymbolRef &Sym) {
+ SmallString<64> Buffer;
+ {
+ raw_svector_ostream OS(Buffer);
+ Sym.printName(OS);
+ }
+
+ const GlobalValue *V = IRFile->getSymbolGV(Sym.getRawDataRefImpl());
+ addDefinedDataSymbol(Buffer.c_str(), V);
+}
+
+void LTOModule::addDefinedDataSymbol(const char *Name, const GlobalValue *v) {
+ // Add to list of defined symbols.
+ addDefinedSymbol(Name, v, false);
+
+ if (!v->hasSection() /* || !isTargetDarwin */)
+ return;
+
+ // Special case i386/ppc ObjC data structures in magic sections:
+ // The issue is that the old ObjC object format did some strange
+ // contortions to avoid real linker symbols. For instance, the
+ // ObjC class data structure is allocated statically in the executable
+ // that defines that class. That data structures contains a pointer to
+ // its superclass. But instead of just initializing that part of the
+ // struct to the address of its superclass, and letting the static and
+ // dynamic linkers do the rest, the runtime works by having that field
+ // instead point to a C-string that is the name of the superclass.
+ // At runtime the objc initialization updates that pointer and sets
+ // it to point to the actual super class. As far as the linker
+ // knows it is just a pointer to a string. But then someone wanted the
+ // linker to issue errors at build time if the superclass was not found.
+ // So they figured out a way in mach-o object format to use an absolute
+ // symbols (.objc_class_name_Foo = 0) and a floating reference
+ // (.reference .objc_class_name_Bar) to cause the linker into erroring when
+ // a class was missing.
+ // The following synthesizes the implicit .objc_* symbols for the linker
+ // from the ObjC data structures generated by the front end.
+
+ // special case if this data blob is an ObjC class definition
+ std::string Section = v->getSection();
+ if (Section.compare(0, 15, "__OBJC,__class,") == 0) {
+ if (const GlobalVariable *gv = dyn_cast<GlobalVariable>(v)) {
+ addObjCClass(gv);
+ }
+ }
+
+ // special case if this data blob is an ObjC category definition
+ else if (Section.compare(0, 18, "__OBJC,__category,") == 0) {
+ if (const GlobalVariable *gv = dyn_cast<GlobalVariable>(v)) {
+ addObjCCategory(gv);
+ }
+ }
+
+ // special case if this data blob is the list of referenced classes
+ else if (Section.compare(0, 18, "__OBJC,__cls_refs,") == 0) {
+ if (const GlobalVariable *gv = dyn_cast<GlobalVariable>(v)) {
+ addObjCClassRef(gv);
+ }
+ }
+}
+
+void LTOModule::addDefinedFunctionSymbol(const object::BasicSymbolRef &Sym) {
+ SmallString<64> Buffer;
+ {
+ raw_svector_ostream OS(Buffer);
+ Sym.printName(OS);
+ }
+
+ const Function *F =
+ cast<Function>(IRFile->getSymbolGV(Sym.getRawDataRefImpl()));
+ addDefinedFunctionSymbol(Buffer.c_str(), F);
+}
+
+void LTOModule::addDefinedFunctionSymbol(const char *Name, const Function *F) {
+ // add to list of defined symbols
+ addDefinedSymbol(Name, F, true);
+}
+
+void LTOModule::addDefinedSymbol(const char *Name, const GlobalValue *def,
+ bool isFunction) {
+ // set alignment part log2() can have rounding errors
+ uint32_t align = def->getAlignment();
+ uint32_t attr = align ? countTrailingZeros(align) : 0;
+
+ // set permissions part
+ if (isFunction) {
+ attr |= LTO_SYMBOL_PERMISSIONS_CODE;
+ } else {
+ const GlobalVariable *gv = dyn_cast<GlobalVariable>(def);
+ if (gv && gv->isConstant())
+ attr |= LTO_SYMBOL_PERMISSIONS_RODATA;
+ else
+ attr |= LTO_SYMBOL_PERMISSIONS_DATA;
+ }
+
+ // set definition part
+ if (def->hasWeakLinkage() || def->hasLinkOnceLinkage())
+ attr |= LTO_SYMBOL_DEFINITION_WEAK;
+ else if (def->hasCommonLinkage())
+ attr |= LTO_SYMBOL_DEFINITION_TENTATIVE;
+ else
+ attr |= LTO_SYMBOL_DEFINITION_REGULAR;
+
+ // set scope part
+ if (def->hasLocalLinkage())
+ // Ignore visibility if linkage is local.
+ attr |= LTO_SYMBOL_SCOPE_INTERNAL;
+ else if (def->hasHiddenVisibility())
+ attr |= LTO_SYMBOL_SCOPE_HIDDEN;
+ else if (def->hasProtectedVisibility())
+ attr |= LTO_SYMBOL_SCOPE_PROTECTED;
+ else if (canBeOmittedFromSymbolTable(def))
+ attr |= LTO_SYMBOL_SCOPE_DEFAULT_CAN_BE_HIDDEN;
+ else
+ attr |= LTO_SYMBOL_SCOPE_DEFAULT;
+
+ auto Iter = _defines.insert(Name).first;
+
+ // fill information structure
+ NameAndAttributes info;
+ StringRef NameRef = Iter->first();
+ info.name = NameRef.data();
+ assert(info.name[NameRef.size()] == '\0');
+ info.attributes = attr;
+ info.isFunction = isFunction;
+ info.symbol = def;
+
+ // add to table of symbols
+ _symbols.push_back(info);
+}
+
+/// addAsmGlobalSymbol - Add a global symbol from module-level ASM to the
+/// defined list.
+void LTOModule::addAsmGlobalSymbol(const char *name,
+ lto_symbol_attributes scope) {
+ auto IterBool = _defines.insert(name);
+
+ // only add new define if not already defined
+ if (!IterBool.second)
+ return;
+
+ NameAndAttributes &info = _undefines[IterBool.first->first().data()];
+
+ if (info.symbol == nullptr) {
+ // FIXME: This is trying to take care of module ASM like this:
+ //
+ // module asm ".zerofill __FOO, __foo, _bar_baz_qux, 0"
+ //
+ // but is gross and its mother dresses it funny. Have the ASM parser give us
+ // more details for this type of situation so that we're not guessing so
+ // much.
+
+ // fill information structure
+ info.name = IterBool.first->first().data();
+ info.attributes =
+ LTO_SYMBOL_PERMISSIONS_DATA | LTO_SYMBOL_DEFINITION_REGULAR | scope;
+ info.isFunction = false;
+ info.symbol = nullptr;
+
+ // add to table of symbols
+ _symbols.push_back(info);
+ return;
+ }
+
+ if (info.isFunction)
+ addDefinedFunctionSymbol(info.name, cast<Function>(info.symbol));
+ else
+ addDefinedDataSymbol(info.name, info.symbol);
+
+ _symbols.back().attributes &= ~LTO_SYMBOL_SCOPE_MASK;
+ _symbols.back().attributes |= scope;
+}
+
+/// addAsmGlobalSymbolUndef - Add a global symbol from module-level ASM to the
+/// undefined list.
+void LTOModule::addAsmGlobalSymbolUndef(const char *name) {
+ auto IterBool = _undefines.insert(std::make_pair(name, NameAndAttributes()));
+
+ _asm_undefines.push_back(IterBool.first->first().data());
+
+ // we already have the symbol
+ if (!IterBool.second)
+ return;
+
+ uint32_t attr = LTO_SYMBOL_DEFINITION_UNDEFINED;
+ attr |= LTO_SYMBOL_SCOPE_DEFAULT;
+ NameAndAttributes &info = IterBool.first->second;
+ info.name = IterBool.first->first().data();
+ info.attributes = attr;
+ info.isFunction = false;
+ info.symbol = nullptr;
+}
+
+/// Add a symbol which isn't defined just yet to a list to be resolved later.
+void LTOModule::addPotentialUndefinedSymbol(const object::BasicSymbolRef &Sym,
+ bool isFunc) {
+ SmallString<64> name;
+ {
+ raw_svector_ostream OS(name);
+ Sym.printName(OS);
+ }
+
+ auto IterBool = _undefines.insert(std::make_pair(name, NameAndAttributes()));
+
+ // we already have the symbol
+ if (!IterBool.second)
+ return;
+
+ NameAndAttributes &info = IterBool.first->second;
+
+ info.name = IterBool.first->first().data();
+
+ const GlobalValue *decl = IRFile->getSymbolGV(Sym.getRawDataRefImpl());
+
+ if (decl->hasExternalWeakLinkage())
+ info.attributes = LTO_SYMBOL_DEFINITION_WEAKUNDEF;
+ else
+ info.attributes = LTO_SYMBOL_DEFINITION_UNDEFINED;
+
+ info.isFunction = isFunc;
+ info.symbol = decl;
+}
+
+/// parseSymbols - Parse the symbols from the module and model-level ASM and add
+/// them to either the defined or undefined lists.
+bool LTOModule::parseSymbols(std::string &errMsg) {
+ for (auto &Sym : IRFile->symbols()) {
+ const GlobalValue *GV = IRFile->getSymbolGV(Sym.getRawDataRefImpl());
+ uint32_t Flags = Sym.getFlags();
+ if (Flags & object::BasicSymbolRef::SF_FormatSpecific)
+ continue;
+
+ bool IsUndefined = Flags & object::BasicSymbolRef::SF_Undefined;
+
+ if (!GV) {
+ SmallString<64> Buffer;
+ {
+ raw_svector_ostream OS(Buffer);
+ Sym.printName(OS);
+ }
+ const char *Name = Buffer.c_str();
+
+ if (IsUndefined)
+ addAsmGlobalSymbolUndef(Name);
+ else if (Flags & object::BasicSymbolRef::SF_Global)
+ addAsmGlobalSymbol(Name, LTO_SYMBOL_SCOPE_DEFAULT);
+ else
+ addAsmGlobalSymbol(Name, LTO_SYMBOL_SCOPE_INTERNAL);
+ continue;
+ }
+
+ auto *F = dyn_cast<Function>(GV);
+ if (IsUndefined) {
+ addPotentialUndefinedSymbol(Sym, F != nullptr);
+ continue;
+ }
+
+ if (F) {
+ addDefinedFunctionSymbol(Sym);
+ continue;
+ }
+
+ if (isa<GlobalVariable>(GV)) {
+ addDefinedDataSymbol(Sym);
+ continue;
+ }
+
+ assert(isa<GlobalAlias>(GV));
+ addDefinedDataSymbol(Sym);
+ }
+
+ // make symbols for all undefines
+ for (StringMap<NameAndAttributes>::iterator u =_undefines.begin(),
+ e = _undefines.end(); u != e; ++u) {
+ // If this symbol also has a definition, then don't make an undefine because
+ // it is a tentative definition.
+ if (_defines.count(u->getKey())) continue;
+ NameAndAttributes info = u->getValue();
+ _symbols.push_back(info);
+ }
+
+ return false;
+}
+
+/// parseMetadata - Parse metadata from the module
+void LTOModule::parseMetadata() {
+ // Linker Options
+ if (Metadata *Val = getModule().getModuleFlag("Linker Options")) {
+ MDNode *LinkerOptions = cast<MDNode>(Val);
+ for (unsigned i = 0, e = LinkerOptions->getNumOperands(); i != e; ++i) {
+ MDNode *MDOptions = cast<MDNode>(LinkerOptions->getOperand(i));
+ for (unsigned ii = 0, ie = MDOptions->getNumOperands(); ii != ie; ++ii) {
+ MDString *MDOption = cast<MDString>(MDOptions->getOperand(ii));
+ // FIXME: Make StringSet::insert match Self-Associative Container
+ // requirements, returning <iter,bool> rather than bool, and use that
+ // here.
+ StringRef Op =
+ _linkeropt_strings.insert(MDOption->getString()).first->first();
+ StringRef DepLibName = _target->getSubtargetImpl()
+ ->getTargetLowering()
+ ->getObjFileLowering()
+ .getDepLibFromLinkerOpt(Op);
+ if (!DepLibName.empty())
+ _deplibs.push_back(DepLibName.data());
+ else if (!Op.empty())
+ _linkeropts.push_back(Op.data());
+ }
+ }
+ }
+
+ // Add other interesting metadata here.
+}
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