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diff --git a/contrib/llvm/tools/lto/LTOModule.cpp b/contrib/llvm/tools/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 "LTOModule.h"
+
+#include "llvm/Constants.h"
+#include "llvm/LLVMContext.h"
+#include "llvm/Module.h"
+#include "llvm/ADT/OwningPtr.h"
+#include "llvm/ADT/Triple.h"
+#include "llvm/Bitcode/ReaderWriter.h"
+#include "llvm/Support/SystemUtils.h"
+#include "llvm/Support/MemoryBuffer.h"
+#include "llvm/Support/MathExtras.h"
+#include "llvm/System/Host.h"
+#include "llvm/System/Path.h"
+#include "llvm/System/Process.h"
+#include "llvm/Target/Mangler.h"
+#include "llvm/Target/SubtargetFeature.h"
+#include "llvm/MC/MCAsmInfo.h"
+#include "llvm/MC/MCContext.h"
+#include "llvm/Target/TargetMachine.h"
+#include "llvm/Target/TargetRegistry.h"
+#include "llvm/Target/TargetSelect.h"
+
+using namespace llvm;
+
+bool LTOModule::isBitcodeFile(const void *mem, size_t length) {
+ return llvm::sys::IdentifyFileType((char*)mem, length)
+ == llvm::sys::Bitcode_FileType;
+}
+
+bool LTOModule::isBitcodeFile(const char *path) {
+ return llvm::sys::Path(path).isBitcodeFile();
+}
+
+bool LTOModule::isBitcodeFileForTarget(const void *mem, size_t length,
+ const char *triplePrefix) {
+ MemoryBuffer *buffer = makeBuffer(mem, length);
+ if (!buffer)
+ return false;
+ return isTargetMatch(buffer, triplePrefix);
+}
+
+
+bool LTOModule::isBitcodeFileForTarget(const char *path,
+ const char *triplePrefix) {
+ MemoryBuffer *buffer = MemoryBuffer::getFile(path);
+ if (buffer == NULL)
+ return false;
+ return isTargetMatch(buffer, triplePrefix);
+}
+
+// Takes ownership of buffer.
+bool LTOModule::isTargetMatch(MemoryBuffer *buffer, const char *triplePrefix) {
+ OwningPtr<Module> m(getLazyBitcodeModule(buffer, getGlobalContext()));
+ // On success, m owns buffer and both are deleted at end of this method.
+ if (!m) {
+ delete buffer;
+ return false;
+ }
+ std::string actualTarget = m->getTargetTriple();
+ return (strncmp(actualTarget.c_str(), triplePrefix,
+ strlen(triplePrefix)) == 0);
+}
+
+
+LTOModule::LTOModule(Module *m, TargetMachine *t)
+ : _module(m), _target(t), _symbolsParsed(false)
+{
+}
+
+LTOModule *LTOModule::makeLTOModule(const char *path,
+ std::string &errMsg) {
+ OwningPtr<MemoryBuffer> buffer(MemoryBuffer::getFile(path, &errMsg));
+ if (!buffer)
+ return NULL;
+ return makeLTOModule(buffer.get(), errMsg);
+}
+
+/// makeBuffer - Create a MemoryBuffer from a memory range. MemoryBuffer
+/// requires the byte past end of the buffer to be a zero. We might get lucky
+/// and already be that way, otherwise make a copy. Also if next byte is on a
+/// different page, don't assume it is readable.
+MemoryBuffer *LTOModule::makeBuffer(const void *mem, size_t length) {
+ const char *startPtr = (char*)mem;
+ const char *endPtr = startPtr+length;
+ if (((uintptr_t)endPtr & (sys::Process::GetPageSize()-1)) == 0 ||
+ *endPtr != 0)
+ return MemoryBuffer::getMemBufferCopy(StringRef(startPtr, length));
+
+ return MemoryBuffer::getMemBuffer(StringRef(startPtr, length));
+}
+
+
+LTOModule *LTOModule::makeLTOModule(const void *mem, size_t length,
+ std::string &errMsg) {
+ OwningPtr<MemoryBuffer> buffer(makeBuffer(mem, length));
+ if (!buffer)
+ return NULL;
+ return makeLTOModule(buffer.get(), errMsg);
+}
+
+LTOModule *LTOModule::makeLTOModule(MemoryBuffer *buffer,
+ std::string &errMsg) {
+ InitializeAllTargets();
+
+ // parse bitcode buffer
+ OwningPtr<Module> m(ParseBitcodeFile(buffer, getGlobalContext(), &errMsg));
+ if (!m)
+ return NULL;
+
+ std::string Triple = m->getTargetTriple();
+ if (Triple.empty())
+ Triple = sys::getHostTriple();
+
+ // find machine architecture for this module
+ const Target *march = TargetRegistry::lookupTarget(Triple, errMsg);
+ if (!march)
+ return NULL;
+
+ // construct LTModule, hand over ownership of module and target
+ SubtargetFeatures Features;
+ Features.getDefaultSubtargetFeatures("" /* cpu */, llvm::Triple(Triple));
+ std::string FeatureStr = Features.getString();
+ TargetMachine *target = march->createTargetMachine(Triple, FeatureStr);
+ return new LTOModule(m.take(), target);
+}
+
+
+const char *LTOModule::getTargetTriple() {
+ return _module->getTargetTriple().c_str();
+}
+
+void LTOModule::setTargetTriple(const char *triple) {
+ _module->setTargetTriple(triple);
+}
+
+void LTOModule::addDefinedFunctionSymbol(Function *f, Mangler &mangler) {
+ // add to list of defined symbols
+ addDefinedSymbol(f, mangler, true);
+
+ // add external symbols referenced by this function.
+ for (Function::iterator b = f->begin(); b != f->end(); ++b) {
+ for (BasicBlock::iterator i = b->begin(); i != b->end(); ++i) {
+ for (unsigned count = 0, total = i->getNumOperands();
+ count != total; ++count) {
+ findExternalRefs(i->getOperand(count), mangler);
+ }
+ }
+ }
+}
+
+// Get string that data pointer points to.
+bool LTOModule::objcClassNameFromExpression(Constant *c, std::string &name) {
+ if (ConstantExpr *ce = dyn_cast<ConstantExpr>(c)) {
+ Constant *op = ce->getOperand(0);
+ if (GlobalVariable *gvn = dyn_cast<GlobalVariable>(op)) {
+ Constant *cn = gvn->getInitializer();
+ if (ConstantArray *ca = dyn_cast<ConstantArray>(cn)) {
+ if (ca->isCString()) {
+ name = ".objc_class_name_" + ca->getAsString();
+ return true;
+ }
+ }
+ }
+ }
+ return false;
+}
+
+// Parse i386/ppc ObjC class data structure.
+void LTOModule::addObjCClass(GlobalVariable *clgv) {
+ if (ConstantStruct *c = dyn_cast<ConstantStruct>(clgv->getInitializer())) {
+ // second slot in __OBJC,__class is pointer to superclass name
+ std::string superclassName;
+ if (objcClassNameFromExpression(c->getOperand(1), superclassName)) {
+ NameAndAttributes info;
+ if (_undefines.find(superclassName.c_str()) == _undefines.end()) {
+ const char *symbolName = ::strdup(superclassName.c_str());
+ info.name = symbolName;
+ info.attributes = LTO_SYMBOL_DEFINITION_UNDEFINED;
+ // string is owned by _undefines
+ _undefines[info.name] = info;
+ }
+ }
+ // third slot in __OBJC,__class is pointer to class name
+ std::string className;
+ if (objcClassNameFromExpression(c->getOperand(2), className)) {
+ const char *symbolName = ::strdup(className.c_str());
+ NameAndAttributes info;
+ info.name = symbolName;
+ info.attributes = (lto_symbol_attributes)
+ (LTO_SYMBOL_PERMISSIONS_DATA |
+ LTO_SYMBOL_DEFINITION_REGULAR |
+ LTO_SYMBOL_SCOPE_DEFAULT);
+ _symbols.push_back(info);
+ _defines[info.name] = 1;
+ }
+ }
+}
+
+
+// Parse i386/ppc ObjC category data structure.
+void LTOModule::addObjCCategory(GlobalVariable *clgv) {
+ if (ConstantStruct *c = dyn_cast<ConstantStruct>(clgv->getInitializer())) {
+ // second slot in __OBJC,__category is pointer to target class name
+ std::string targetclassName;
+ if (objcClassNameFromExpression(c->getOperand(1), targetclassName)) {
+ NameAndAttributes info;
+ if (_undefines.find(targetclassName.c_str()) == _undefines.end()) {
+ const char *symbolName = ::strdup(targetclassName.c_str());
+ info.name = symbolName;
+ info.attributes = LTO_SYMBOL_DEFINITION_UNDEFINED;
+ // string is owned by _undefines
+ _undefines[info.name] = info;
+ }
+ }
+ }
+}
+
+
+// Parse i386/ppc ObjC class list data structure.
+void LTOModule::addObjCClassRef(GlobalVariable *clgv) {
+ std::string targetclassName;
+ if (objcClassNameFromExpression(clgv->getInitializer(), targetclassName)) {
+ NameAndAttributes info;
+ if (_undefines.find(targetclassName.c_str()) == _undefines.end()) {
+ const char *symbolName = ::strdup(targetclassName.c_str());
+ info.name = symbolName;
+ info.attributes = LTO_SYMBOL_DEFINITION_UNDEFINED;
+ // string is owned by _undefines
+ _undefines[info.name] = info;
+ }
+ }
+}
+
+
+void LTOModule::addDefinedDataSymbol(GlobalValue *v, Mangler &mangler) {
+ // Add to list of defined symbols.
+ addDefinedSymbol(v, mangler, false);
+
+ // 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.
+ if (v->hasSection() /* && isTargetDarwin */) {
+ // special case if this data blob is an ObjC class definition
+ if (v->getSection().compare(0, 15, "__OBJC,__class,") == 0) {
+ if (GlobalVariable *gv = dyn_cast<GlobalVariable>(v)) {
+ addObjCClass(gv);
+ }
+ }
+
+ // special case if this data blob is an ObjC category definition
+ else if (v->getSection().compare(0, 18, "__OBJC,__category,") == 0) {
+ if (GlobalVariable *gv = dyn_cast<GlobalVariable>(v)) {
+ addObjCCategory(gv);
+ }
+ }
+
+ // special case if this data blob is the list of referenced classes
+ else if (v->getSection().compare(0, 18, "__OBJC,__cls_refs,") == 0) {
+ if (GlobalVariable *gv = dyn_cast<GlobalVariable>(v)) {
+ addObjCClassRef(gv);
+ }
+ }
+ }
+
+ // add external symbols referenced by this data.
+ for (unsigned count = 0, total = v->getNumOperands();
+ count != total; ++count) {
+ findExternalRefs(v->getOperand(count), mangler);
+ }
+}
+
+
+void LTOModule::addDefinedSymbol(GlobalValue *def, Mangler &mangler,
+ bool isFunction) {
+ // ignore all llvm.* symbols
+ if (def->getName().startswith("llvm."))
+ return;
+
+ // string is owned by _defines
+ const char *symbolName = ::strdup(mangler.getNameWithPrefix(def).c_str());
+
+ // set alignment part log2() can have rounding errors
+ uint32_t align = def->getAlignment();
+ uint32_t attr = align ? CountTrailingZeros_32(def->getAlignment()) : 0;
+
+ // set permissions part
+ if (isFunction)
+ attr |= LTO_SYMBOL_PERMISSIONS_CODE;
+ else {
+ 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->hasHiddenVisibility())
+ attr |= LTO_SYMBOL_SCOPE_HIDDEN;
+ else if (def->hasProtectedVisibility())
+ attr |= LTO_SYMBOL_SCOPE_PROTECTED;
+ else if (def->hasExternalLinkage() || def->hasWeakLinkage()
+ || def->hasLinkOnceLinkage() || def->hasCommonLinkage())
+ attr |= LTO_SYMBOL_SCOPE_DEFAULT;
+ else
+ attr |= LTO_SYMBOL_SCOPE_INTERNAL;
+
+ // add to table of symbols
+ NameAndAttributes info;
+ info.name = symbolName;
+ info.attributes = (lto_symbol_attributes)attr;
+ _symbols.push_back(info);
+ _defines[info.name] = 1;
+}
+
+void LTOModule::addAsmGlobalSymbol(const char *name) {
+ // only add new define if not already defined
+ if (_defines.count(name))
+ return;
+
+ // string is owned by _defines
+ const char *symbolName = ::strdup(name);
+ uint32_t attr = LTO_SYMBOL_DEFINITION_REGULAR;
+ attr |= LTO_SYMBOL_SCOPE_DEFAULT;
+ NameAndAttributes info;
+ info.name = symbolName;
+ info.attributes = (lto_symbol_attributes)attr;
+ _symbols.push_back(info);
+ _defines[info.name] = 1;
+}
+
+void LTOModule::addPotentialUndefinedSymbol(GlobalValue *decl,
+ Mangler &mangler) {
+ // ignore all llvm.* symbols
+ if (decl->getName().startswith("llvm."))
+ return;
+
+ // ignore all aliases
+ if (isa<GlobalAlias>(decl))
+ return;
+
+ std::string name = mangler.getNameWithPrefix(decl);
+
+ // we already have the symbol
+ if (_undefines.find(name) != _undefines.end())
+ return;
+
+ NameAndAttributes info;
+ // string is owned by _undefines
+ info.name = ::strdup(name.c_str());
+ if (decl->hasExternalWeakLinkage())
+ info.attributes = LTO_SYMBOL_DEFINITION_WEAKUNDEF;
+ else
+ info.attributes = LTO_SYMBOL_DEFINITION_UNDEFINED;
+ _undefines[name] = info;
+}
+
+
+
+// Find external symbols referenced by VALUE. This is a recursive function.
+void LTOModule::findExternalRefs(Value *value, Mangler &mangler) {
+ if (GlobalValue *gv = dyn_cast<GlobalValue>(value)) {
+ if (!gv->hasExternalLinkage())
+ addPotentialUndefinedSymbol(gv, mangler);
+ // If this is a variable definition, do not recursively process
+ // initializer. It might contain a reference to this variable
+ // and cause an infinite loop. The initializer will be
+ // processed in addDefinedDataSymbol().
+ return;
+ }
+
+ // GlobalValue, even with InternalLinkage type, may have operands with
+ // ExternalLinkage type. Do not ignore these operands.
+ if (Constant *c = dyn_cast<Constant>(value)) {
+ // Handle ConstantExpr, ConstantStruct, ConstantArry etc.
+ for (unsigned i = 0, e = c->getNumOperands(); i != e; ++i)
+ findExternalRefs(c->getOperand(i), mangler);
+ }
+}
+
+void LTOModule::lazyParseSymbols() {
+ if (_symbolsParsed)
+ return;
+
+ _symbolsParsed = true;
+
+ // Use mangler to add GlobalPrefix to names to match linker names.
+ MCContext Context(*_target->getMCAsmInfo());
+ Mangler mangler(Context, *_target->getTargetData());
+
+ // add functions
+ for (Module::iterator f = _module->begin(); f != _module->end(); ++f) {
+ if (f->isDeclaration())
+ addPotentialUndefinedSymbol(f, mangler);
+ else
+ addDefinedFunctionSymbol(f, mangler);
+ }
+
+ // add data
+ for (Module::global_iterator v = _module->global_begin(),
+ e = _module->global_end(); v != e; ++v) {
+ if (v->isDeclaration())
+ addPotentialUndefinedSymbol(v, mangler);
+ else
+ addDefinedDataSymbol(v, mangler);
+ }
+
+ // add asm globals
+ const std::string &inlineAsm = _module->getModuleInlineAsm();
+ const std::string glbl = ".globl";
+ std::string asmSymbolName;
+ std::string::size_type pos = inlineAsm.find(glbl, 0);
+ while (pos != std::string::npos) {
+ // eat .globl
+ pos = pos + 6;
+
+ // skip white space between .globl and symbol name
+ std::string::size_type pbegin = inlineAsm.find_first_not_of(' ', pos);
+ if (pbegin == std::string::npos)
+ break;
+
+ // find end-of-line
+ std::string::size_type pend = inlineAsm.find_first_of('\n', pbegin);
+ if (pend == std::string::npos)
+ break;
+
+ asmSymbolName.assign(inlineAsm, pbegin, pend - pbegin);
+ addAsmGlobalSymbol(asmSymbolName.c_str());
+
+ // search next .globl
+ pos = inlineAsm.find(glbl, pend);
+ }
+
+ // make symbols for all undefines
+ for (StringMap<NameAndAttributes>::iterator it=_undefines.begin();
+ it != _undefines.end(); ++it) {
+ // if this symbol also has a definition, then don't make an undefine
+ // because it is a tentative definition
+ if (_defines.count(it->getKey()) == 0) {
+ NameAndAttributes info = it->getValue();
+ _symbols.push_back(info);
+ }
+ }
+}
+
+
+uint32_t LTOModule::getSymbolCount() {
+ lazyParseSymbols();
+ return _symbols.size();
+}
+
+
+lto_symbol_attributes LTOModule::getSymbolAttributes(uint32_t index) {
+ lazyParseSymbols();
+ if (index < _symbols.size())
+ return _symbols[index].attributes;
+ else
+ return lto_symbol_attributes(0);
+}
+
+const char *LTOModule::getSymbolName(uint32_t index) {
+ lazyParseSymbols();
+ if (index < _symbols.size())
+ return _symbols[index].name;
+ else
+ return NULL;
+}
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