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;
}
Beispiel #2
0
/// 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");
}