bool X86IntelAsmPrinter::doInitialization(Module &M) { bool Result = AsmPrinter::doInitialization(M); Mang->markCharUnacceptable('.'); O << "\t.686\n\t.model flat\n\n"; // Emit declarations for external functions. for (Module::iterator I = M.begin(), E = M.end(); I != E; ++I) if (I->isDeclaration()) { std::string Name = Mang->getValueName(I); decorateName(Name, I); O << "\textern " ; if (I->hasDLLImportLinkage()) { O << "__imp_"; } O << Name << ":near\n"; } // Emit declarations for external globals. Note that VC++ always declares // external globals to have type byte, and if that's good enough for VC++... for (Module::const_global_iterator I = M.global_begin(), E = M.global_end(); I != E; ++I) { if (I->isDeclaration()) { std::string Name = Mang->getValueName(I); O << "\textern " ; if (I->hasDLLImportLinkage()) { O << "__imp_"; } O << Name << ":byte\n"; } } return Result; }
void PIC16AsmPrinter::EmitExternsAndGlobals (Module &M) { // Emit declarations for external functions. O << "section.0" <<"\n"; for (Module::iterator I = M.begin(), E = M.end(); I != E; I++) { std::string Name = Mang->getValueName(I); if (Name.compare("abort") == 0) continue; if (I->isDeclaration()) { O << "\textern " <<Name << "\n"; O << "\textern " << Name << ".retval\n"; O << "\textern " << Name << ".args\n"; } else if (I->hasExternalLinkage()) { O << "\tglobal " << Name << "\n"; O << "\tglobal " << Name << ".retval\n"; O << "\tglobal " << Name << ".args\n"; } } // Emit header file to include declaration of library functions O << "\t#include C16IntrinsicCalls.INC\n"; // Emit declarations for external globals. for (Module::const_global_iterator I = M.global_begin(), E = M.global_end(); I != E; I++) { // Any variables reaching here with ".auto." in its name is a local scope // variable and should not be printed in global data section. std::string Name = Mang->getValueName(I); if (isLocalName (Name)) continue; if (I->isDeclaration()) O << "\textern "<< Name << "\n"; else if (I->hasCommonLinkage() || I->hasExternalLinkage()) O << "\tglobal "<< Name << "\n"; } }
/// EmitGlobals - Emit all of the global variables to memory, storing their /// addresses into GlobalAddress. This must make sure to copy the contents of /// their initializers into the memory. /// void ExecutionEngine::emitGlobals() { // Loop over all of the global variables in the program, allocating the memory // to hold them. If there is more than one module, do a prepass over globals // to figure out how the different modules should link together. // std::map<std::pair<std::string, const Type*>, const GlobalValue*> LinkedGlobalsMap; if (Modules.size() != 1) { for (unsigned m = 0, e = Modules.size(); m != e; ++m) { Module &M = *Modules[m]->getModule(); for (Module::const_global_iterator I = M.global_begin(), E = M.global_end(); I != E; ++I) { const GlobalValue *GV = I; if (GV->hasLocalLinkage() || GV->isDeclaration() || GV->hasAppendingLinkage() || !GV->hasName()) continue;// Ignore external globals and globals with internal linkage. const GlobalValue *&GVEntry = LinkedGlobalsMap[std::make_pair(GV->getName(), GV->getType())]; // If this is the first time we've seen this global, it is the canonical // version. if (!GVEntry) { GVEntry = GV; continue; } // If the existing global is strong, never replace it. if (GVEntry->hasExternalLinkage() || GVEntry->hasDLLImportLinkage() || GVEntry->hasDLLExportLinkage()) continue; // Otherwise, we know it's linkonce/weak, replace it if this is a strong // symbol. FIXME is this right for common? if (GV->hasExternalLinkage() || GVEntry->hasExternalWeakLinkage()) GVEntry = GV; } } } std::vector<const GlobalValue*> NonCanonicalGlobals; for (unsigned m = 0, e = Modules.size(); m != e; ++m) { Module &M = *Modules[m]->getModule(); for (Module::const_global_iterator I = M.global_begin(), E = M.global_end(); I != E; ++I) { // In the multi-module case, see what this global maps to. if (!LinkedGlobalsMap.empty()) { if (const GlobalValue *GVEntry = LinkedGlobalsMap[std::make_pair(I->getName(), I->getType())]) { // If something else is the canonical global, ignore this one. if (GVEntry != &*I) { NonCanonicalGlobals.push_back(I); continue; } } } if (!I->isDeclaration()) { addGlobalMapping(I, getMemoryForGV(I)); } else { // External variable reference. Try to use the dynamic loader to // get a pointer to it. if (void *SymAddr = sys::DynamicLibrary::SearchForAddressOfSymbol(I->getName().c_str())) addGlobalMapping(I, SymAddr); else { cerr << "Could not resolve external global address: " << I->getName() << "\n"; abort(); } } } // If there are multiple modules, map the non-canonical globals to their // canonical location. if (!NonCanonicalGlobals.empty()) { for (unsigned i = 0, e = NonCanonicalGlobals.size(); i != e; ++i) { const GlobalValue *GV = NonCanonicalGlobals[i]; const GlobalValue *CGV = LinkedGlobalsMap[std::make_pair(GV->getName(), GV->getType())]; void *Ptr = getPointerToGlobalIfAvailable(CGV); assert(Ptr && "Canonical global wasn't codegen'd!"); addGlobalMapping(GV, Ptr); } } // Now that all of the globals are set up in memory, loop through them all // and initialize their contents. for (Module::const_global_iterator I = M.global_begin(), E = M.global_end(); I != E; ++I) { if (!I->isDeclaration()) { if (!LinkedGlobalsMap.empty()) { if (const GlobalValue *GVEntry = LinkedGlobalsMap[std::make_pair(I->getName(), I->getType())]) if (GVEntry != &*I) // Not the canonical variable. continue; } EmitGlobalVariable(I); } } } }
void externalsAndGlobalsCheck(const Module *m) { std::map<std::string, bool> externals; std::set<std::string> modelled(modelledExternals, modelledExternals+NELEMS(modelledExternals)); std::set<std::string> dontCare(dontCareExternals, dontCareExternals+NELEMS(dontCareExternals)); std::set<std::string> unsafe(unsafeExternals, unsafeExternals+NELEMS(unsafeExternals)); switch (Libc) { case KleeLibc: dontCare.insert(dontCareKlee, dontCareKlee+NELEMS(dontCareKlee)); break; case UcLibc: dontCare.insert(dontCareUclibc, dontCareUclibc+NELEMS(dontCareUclibc)); break; case NoLibc: /* silence compiler warning */ break; } if (WithPOSIXRuntime) dontCare.insert("syscall"); for (Module::const_iterator fnIt = m->begin(), fn_ie = m->end(); fnIt != fn_ie; ++fnIt) { if (fnIt->isDeclaration() && !fnIt->use_empty()) externals.insert(std::make_pair(fnIt->getName(), false)); for (Function::const_iterator bbIt = fnIt->begin(), bb_ie = fnIt->end(); bbIt != bb_ie; ++bbIt) { for (BasicBlock::const_iterator it = bbIt->begin(), ie = bbIt->end(); it != ie; ++it) { if (const CallInst *ci = dyn_cast<CallInst>(it)) { if (isa<InlineAsm>(ci->getCalledValue())) { klee_warning_once(&*fnIt, "function \"%s\" has inline asm", fnIt->getName().data()); } } } } } for (Module::const_global_iterator it = m->global_begin(), ie = m->global_end(); it != ie; ++it) if (it->isDeclaration() && !it->use_empty()) externals.insert(std::make_pair(it->getName(), true)); // and remove aliases (they define the symbol after global // initialization) for (Module::const_alias_iterator it = m->alias_begin(), ie = m->alias_end(); it != ie; ++it) { std::map<std::string, bool>::iterator it2 = externals.find(it->getName()); if (it2!=externals.end()) externals.erase(it2); } std::map<std::string, bool> foundUnsafe; for (std::map<std::string, bool>::iterator it = externals.begin(), ie = externals.end(); it != ie; ++it) { const std::string &ext = it->first; if (!modelled.count(ext) && (WarnAllExternals || !dontCare.count(ext))) { if (unsafe.count(ext)) { foundUnsafe.insert(*it); } else { klee_warning("undefined reference to %s: %s", it->second ? "variable" : "function", ext.c_str()); } } } for (std::map<std::string, bool>::iterator it = foundUnsafe.begin(), ie = foundUnsafe.end(); it != ie; ++it) { const std::string &ext = it->first; klee_warning("undefined reference to %s: %s (UNSAFE)!", it->second ? "variable" : "function", ext.c_str()); } }
/// Based on GetAllUndefinedSymbols() from LLVM3.2 /// /// GetAllUndefinedSymbols - calculates the set of undefined symbols that still /// exist in an LLVM module. This is a bit tricky because there may be two /// symbols with the same name but different LLVM types that will be resolved to /// each other but aren't currently (thus we need to treat it as resolved). /// /// Inputs: /// M - The module in which to find undefined symbols. /// /// Outputs: /// UndefinedSymbols - A set of C++ strings containing the name of all /// undefined symbols. /// static void GetAllUndefinedSymbols(Module *M, std::set<std::string> &UndefinedSymbols) { static const std::string llvmIntrinsicPrefix="llvm."; std::set<std::string> DefinedSymbols; UndefinedSymbols.clear(); KLEE_DEBUG_WITH_TYPE("klee_linker", dbgs() << "*** Computing undefined symbols for " << M->getModuleIdentifier() << " ***\n"); for (auto const &Function : *M) { if (Function.hasName()) { if (Function.isDeclaration()) UndefinedSymbols.insert(Function.getName()); else if (!Function.hasLocalLinkage()) { #if LLVM_VERSION_CODE < LLVM_VERSION(3, 5) assert(!Function.hasDLLImportLinkage() && "Found dllimported non-external symbol!"); #else assert(!Function.hasDLLImportStorageClass() && "Found dllimported non-external symbol!"); #endif DefinedSymbols.insert(Function.getName()); } } } for (Module::const_global_iterator I = M->global_begin(), E = M->global_end(); I != E; ++I) if (I->hasName()) { if (I->isDeclaration()) UndefinedSymbols.insert(I->getName()); else if (!I->hasLocalLinkage()) { #if LLVM_VERSION_CODE < LLVM_VERSION(3, 5) assert(!I->hasDLLImportLinkage() && "Found dllimported non-external symbol!"); #else assert(!I->hasDLLImportStorageClass() && "Found dllimported non-external symbol!"); #endif DefinedSymbols.insert(I->getName()); } } for (Module::const_alias_iterator I = M->alias_begin(), E = M->alias_end(); I != E; ++I) if (I->hasName()) DefinedSymbols.insert(I->getName()); // Prune out any defined symbols from the undefined symbols set // and other symbols we don't want to treat as an undefined symbol std::vector<std::string> SymbolsToRemove; for (std::set<std::string>::iterator I = UndefinedSymbols.begin(); I != UndefinedSymbols.end(); ++I ) { if (DefinedSymbols.find(*I) != DefinedSymbols.end()) { SymbolsToRemove.push_back(*I); continue; } // Strip out llvm intrinsics if ( (I->size() >= llvmIntrinsicPrefix.size() ) && (I->compare(0, llvmIntrinsicPrefix.size(), llvmIntrinsicPrefix) == 0) ) { KLEE_DEBUG_WITH_TYPE("klee_linker", dbgs() << "LLVM intrinsic " << *I << " has will be removed from undefined symbols"<< "\n"); SymbolsToRemove.push_back(*I); continue; } // Symbol really is undefined KLEE_DEBUG_WITH_TYPE("klee_linker", dbgs() << "Symbol " << *I << " is undefined.\n"); } // Now remove the symbols from undefined set. for (auto const &symbol : SymbolsToRemove) UndefinedSymbols.erase(symbol); KLEE_DEBUG_WITH_TYPE("klee_linker", dbgs() << "*** Finished computing undefined symbols ***\n"); }
bool X86IntelAsmPrinter::doFinalization(Module &M) { const TargetData *TD = TM.getTargetData(); // Print out module-level global variables here. for (Module::const_global_iterator I = M.global_begin(), E = M.global_end(); I != E; ++I) { if (I->isDeclaration()) continue; // External global require no code // Check to see if this is a special global used by LLVM, if so, emit it. if (EmitSpecialLLVMGlobal(I)) continue; std::string name = Mang->getValueName(I); Constant *C = I->getInitializer(); unsigned Align = TD->getPreferredAlignmentLog(I); bool bCustomSegment = false; switch (I->getLinkage()) { case GlobalValue::CommonLinkage: case GlobalValue::LinkOnceLinkage: case GlobalValue::WeakLinkage: SwitchToDataSection(""); O << name << "?\tsegment common 'COMMON'\n"; bCustomSegment = true; // FIXME: the default alignment is 16 bytes, but 1, 2, 4, and 256 // are also available. break; case GlobalValue::AppendingLinkage: SwitchToDataSection(""); O << name << "?\tsegment public 'DATA'\n"; bCustomSegment = true; // FIXME: the default alignment is 16 bytes, but 1, 2, 4, and 256 // are also available. break; case GlobalValue::DLLExportLinkage: DLLExportedGVs.insert(name); // FALL THROUGH case GlobalValue::ExternalLinkage: O << "\tpublic " << name << "\n"; // FALL THROUGH case GlobalValue::InternalLinkage: SwitchToSection(TAI->getDataSection()); break; default: assert(0 && "Unknown linkage type!"); } if (!bCustomSegment) EmitAlignment(Align, I); O << name << ":\t\t\t\t" << TAI->getCommentString() << " " << I->getName() << '\n'; EmitGlobalConstant(C); if (bCustomSegment) O << name << "?\tends\n"; } // Output linker support code for dllexported globals if (!DLLExportedGVs.empty() || !DLLExportedFns.empty()) { SwitchToDataSection(""); O << "; WARNING: The following code is valid only with MASM v8.x" << "and (possible) higher\n" << "; This version of MASM is usually shipped with Microsoft " << "Visual Studio 2005\n" << "; or (possible) further versions. Unfortunately, there is no " << "way to support\n" << "; dllexported symbols in the earlier versions of MASM in fully " << "automatic way\n\n"; O << "_drectve\t segment info alias('.drectve')\n"; } for (StringSet<>::iterator i = DLLExportedGVs.begin(), e = DLLExportedGVs.end(); i != e; ++i) O << "\t db ' /EXPORT:" << i->getKeyData() << ",data'\n"; for (StringSet<>::iterator i = DLLExportedFns.begin(), e = DLLExportedFns.end(); i != e; ++i) O << "\t db ' /EXPORT:" << i->getKeyData() << "'\n"; if (!DLLExportedGVs.empty() || !DLLExportedFns.empty()) O << "_drectve\t ends\n"; // Bypass X86SharedAsmPrinter::doFinalization(). bool Result = AsmPrinter::doFinalization(M); SwitchToDataSection(""); O << "\tend\n"; return Result; }
std::unique_ptr<Module> llvm::CloneModule( const Module *M, ValueToValueMapTy &VMap, function_ref<bool(const GlobalValue *)> ShouldCloneDefinition) { // First off, we need to create the new module. std::unique_ptr<Module> New = llvm::make_unique<Module>(M->getModuleIdentifier(), M->getContext()); New->setDataLayout(M->getDataLayout()); New->setTargetTriple(M->getTargetTriple()); New->setModuleInlineAsm(M->getModuleInlineAsm()); // Loop over all of the global variables, making corresponding globals in the // new module. Here we add them to the VMap and to the new Module. We // don't worry about attributes or initializers, they will come later. // for (Module::const_global_iterator I = M->global_begin(), E = M->global_end(); I != E; ++I) { GlobalVariable *GV = new GlobalVariable(*New, I->getValueType(), I->isConstant(), I->getLinkage(), (Constant*) nullptr, I->getName(), (GlobalVariable*) nullptr, I->getThreadLocalMode(), I->getType()->getAddressSpace()); GV->copyAttributesFrom(&*I); VMap[&*I] = GV; } // Loop over the functions in the module, making external functions as before for (const Function &I : *M) { Function *NF = Function::Create(cast<FunctionType>(I.getValueType()), I.getLinkage(), I.getName(), New.get()); NF->copyAttributesFrom(&I); VMap[&I] = NF; } // Loop over the aliases in the module for (Module::const_alias_iterator I = M->alias_begin(), E = M->alias_end(); I != E; ++I) { if (!ShouldCloneDefinition(&*I)) { // An alias cannot act as an external reference, so we need to create // either a function or a global variable depending on the value type. // FIXME: Once pointee types are gone we can probably pick one or the // other. GlobalValue *GV; if (I->getValueType()->isFunctionTy()) GV = Function::Create(cast<FunctionType>(I->getValueType()), GlobalValue::ExternalLinkage, I->getName(), New.get()); else GV = new GlobalVariable( *New, I->getValueType(), false, GlobalValue::ExternalLinkage, (Constant *)nullptr, I->getName(), (GlobalVariable *)nullptr, I->getThreadLocalMode(), I->getType()->getAddressSpace()); VMap[&*I] = GV; // We do not copy attributes (mainly because copying between different // kinds of globals is forbidden), but this is generally not required for // correctness. continue; } auto *GA = GlobalAlias::create(I->getValueType(), I->getType()->getPointerAddressSpace(), I->getLinkage(), I->getName(), New.get()); GA->copyAttributesFrom(&*I); VMap[&*I] = GA; } // Now that all of the things that global variable initializer can refer to // have been created, loop through and copy the global variable referrers // over... We also set the attributes on the global now. // for (Module::const_global_iterator I = M->global_begin(), E = M->global_end(); I != E; ++I) { if (I->isDeclaration()) continue; GlobalVariable *GV = cast<GlobalVariable>(VMap[&*I]); if (!ShouldCloneDefinition(&*I)) { // Skip after setting the correct linkage for an external reference. GV->setLinkage(GlobalValue::ExternalLinkage); continue; } if (I->hasInitializer()) GV->setInitializer(MapValue(I->getInitializer(), VMap)); SmallVector<std::pair<unsigned, MDNode *>, 1> MDs; I->getAllMetadata(MDs); for (auto MD : MDs) GV->addMetadata(MD.first, *MapMetadata(MD.second, VMap)); } // Similarly, copy over function bodies now... // for (const Function &I : *M) { if (I.isDeclaration()) continue; Function *F = cast<Function>(VMap[&I]); if (!ShouldCloneDefinition(&I)) { // Skip after setting the correct linkage for an external reference. F->setLinkage(GlobalValue::ExternalLinkage); // Personality function is not valid on a declaration. F->setPersonalityFn(nullptr); continue; } Function::arg_iterator DestI = F->arg_begin(); for (Function::const_arg_iterator J = I.arg_begin(); J != I.arg_end(); ++J) { DestI->setName(J->getName()); VMap[&*J] = &*DestI++; } SmallVector<ReturnInst *, 8> Returns; // Ignore returns cloned. CloneFunctionInto(F, &I, VMap, /*ModuleLevelChanges=*/true, Returns); if (I.hasPersonalityFn()) F->setPersonalityFn(MapValue(I.getPersonalityFn(), VMap)); } // And aliases for (Module::const_alias_iterator I = M->alias_begin(), E = M->alias_end(); I != E; ++I) { // We already dealt with undefined aliases above. if (!ShouldCloneDefinition(&*I)) continue; GlobalAlias *GA = cast<GlobalAlias>(VMap[&*I]); if (const Constant *C = I->getAliasee()) GA->setAliasee(MapValue(C, VMap)); } // And named metadata.... for (Module::const_named_metadata_iterator I = M->named_metadata_begin(), E = M->named_metadata_end(); I != E; ++I) { const NamedMDNode &NMD = *I; NamedMDNode *NewNMD = New->getOrInsertNamedMetadata(NMD.getName()); for (unsigned i = 0, e = NMD.getNumOperands(); i != e; ++i) NewNMD->addOperand(MapMetadata(NMD.getOperand(i), VMap)); } return New; }