C++ iterator::getFunctionType方法代码示例

/// CleanupAndPrepareModules - Get the specified modules ready for code
/// generator testing.
///
static void CleanupAndPrepareModules(BugDriver &BD, Module *&Test,
                                     Module *Safe) {
  // Clean up the modules, removing extra cruft that we don't need anymore...
  Test = BD.performFinalCleanups(Test);

  // If we are executing the JIT, we have several nasty issues to take care of.
  if (!BD.isExecutingJIT()) return;

  // First, if the main function is in the Safe module, we must add a stub to
  // the Test module to call into it.  Thus, we create a new function `main'
  // which just calls the old one.
  if (Function *oldMain = Safe->getFunction("main"))
    if (!oldMain->isDeclaration()) {
      // Rename it
      oldMain->setName("llvm_bugpoint_old_main");
      // Create a NEW `main' function with same type in the test module.
      Function *newMain = Function::Create(oldMain->getFunctionType(),
                                           GlobalValue::ExternalLinkage,
                                           "main", Test);
      // Create an `oldmain' prototype in the test module, which will
      // corresponds to the real main function in the same module.
      Function *oldMainProto = Function::Create(oldMain->getFunctionType(),
                                                GlobalValue::ExternalLinkage,
                                                oldMain->getName(), Test);
      // Set up and remember the argument list for the main function.
      std::vector<Value*> args;
      for (Function::arg_iterator
             I = newMain->arg_begin(), E = newMain->arg_end(),
             OI = oldMain->arg_begin(); I != E; ++I, ++OI) {
        I->setName(OI->getName());    // Copy argument names from oldMain
        args.push_back(I);
      }

      // Call the old main function and return its result
      BasicBlock *BB = BasicBlock::Create(Safe->getContext(), "entry", newMain);
      CallInst *call = CallInst::Create(oldMainProto, args.begin(), args.end(),
                                        "", BB);

      // If the type of old function wasn't void, return value of call
      ReturnInst::Create(Safe->getContext(), call, BB);
    }

  // The second nasty issue we must deal with in the JIT is that the Safe
  // module cannot directly reference any functions defined in the test
  // module.  Instead, we use a JIT API call to dynamically resolve the
  // symbol.

  // Add the resolver to the Safe module.
  // Prototype: void *getPointerToNamedFunction(const char* Name)
  Constant *resolverFunc =
    Safe->getOrInsertFunction("getPointerToNamedFunction",
                    Type::getInt8PtrTy(Safe->getContext()),
                    Type::getInt8PtrTy(Safe->getContext()),
                       (Type *)0);

  // Use the function we just added to get addresses of functions we need.
  for (Module::iterator F = Safe->begin(), E = Safe->end(); F != E; ++F) {
    if (F->isDeclaration() && !F->use_empty() && &*F != resolverFunc &&
        !F->isIntrinsic() /* ignore intrinsics */) {
      Function *TestFn = Test->getFunction(F->getName());

      // Don't forward functions which are external in the test module too.
      if (TestFn && !TestFn->isDeclaration()) {
        // 1. Add a string constant with its name to the global file
        Constant *InitArray = ConstantArray::get(F->getContext(), F->getName());
        GlobalVariable *funcName =
          new GlobalVariable(*Safe, InitArray->getType(), true /*isConstant*/,
                             GlobalValue::InternalLinkage, InitArray,
                             F->getName() + "_name");

        // 2. Use `GetElementPtr *funcName, 0, 0' to convert the string to an
        // sbyte* so it matches the signature of the resolver function.

        // GetElementPtr *funcName, ulong 0, ulong 0
        std::vector<Constant*> GEPargs(2,
                     Constant::getNullValue(Type::getInt32Ty(F->getContext())));
        Value *GEP =
                ConstantExpr::getGetElementPtr(funcName, &GEPargs[0], 2);
        std::vector<Value*> ResolverArgs;
        ResolverArgs.push_back(GEP);

        // Rewrite uses of F in global initializers, etc. to uses of a wrapper
        // function that dynamically resolves the calls to F via our JIT API
        if (!F->use_empty()) {
          // Create a new global to hold the cached function pointer.
          Constant *NullPtr = ConstantPointerNull::get(F->getType());
          GlobalVariable *Cache =
            new GlobalVariable(*F->getParent(), F->getType(), 
                               false, GlobalValue::InternalLinkage,
                               NullPtr,F->getName()+".fpcache");

          // Construct a new stub function that will re-route calls to F
          const FunctionType *FuncTy = F->getFunctionType();
          Function *FuncWrapper = Function::Create(FuncTy,
                                                   GlobalValue::InternalLinkage,
                                                   F->getName() + "_wrapper",
                                                   F->getParent());
//.........这里部分代码省略.........

/// ExtractLoops - Given a reduced list of functions that still exposed the bug,
/// check to see if we can extract the loops in the region without obscuring the
/// bug.  If so, it reduces the amount of code identified.
///
static bool ExtractLoops(BugDriver &BD,
                         bool (*TestFn)(BugDriver &, Module *, Module *,
                                        std::string &),
                         std::vector<Function*> &MiscompiledFunctions,
                         std::string &Error) {
  bool MadeChange = false;
  while (1) {
    if (BugpointIsInterrupted) return MadeChange;
    
    DenseMap<const Value*, Value*> ValueMap;
    Module *ToNotOptimize = CloneModule(BD.getProgram(), ValueMap);
    Module *ToOptimize = SplitFunctionsOutOfModule(ToNotOptimize,
                                                   MiscompiledFunctions,
                                                   ValueMap);
    Module *ToOptimizeLoopExtracted = BD.ExtractLoop(ToOptimize);
    if (!ToOptimizeLoopExtracted) {
      // If the loop extractor crashed or if there were no extractible loops,
      // then this chapter of our odyssey is over with.
      delete ToNotOptimize;
      delete ToOptimize;
      return MadeChange;
    }

    errs() << "Extracted a loop from the breaking portion of the program.\n";

    // Bugpoint is intentionally not very trusting of LLVM transformations.  In
    // particular, we're not going to assume that the loop extractor works, so
    // we're going to test the newly loop extracted program to make sure nothing
    // has broken.  If something broke, then we'll inform the user and stop
    // extraction.
    AbstractInterpreter *AI = BD.switchToSafeInterpreter();
    bool Failure = TestMergedProgram(BD, ToOptimizeLoopExtracted, ToNotOptimize,
                                     false, Error);
    if (!Error.empty())
      return false;
    if (Failure) {
      BD.switchToInterpreter(AI);

      // Merged program doesn't work anymore!
      errs() << "  *** ERROR: Loop extraction broke the program. :("
             << " Please report a bug!\n";
      errs() << "      Continuing on with un-loop-extracted version.\n";

      BD.writeProgramToFile(OutputPrefix + "-loop-extract-fail-tno.bc",
                            ToNotOptimize);
      BD.writeProgramToFile(OutputPrefix + "-loop-extract-fail-to.bc",
                            ToOptimize);
      BD.writeProgramToFile(OutputPrefix + "-loop-extract-fail-to-le.bc",
                            ToOptimizeLoopExtracted);

      errs() << "Please submit the " 
             << OutputPrefix << "-loop-extract-fail-*.bc files.\n";
      delete ToOptimize;
      delete ToNotOptimize;
      delete ToOptimizeLoopExtracted;
      return MadeChange;
    }
    delete ToOptimize;
    BD.switchToInterpreter(AI);

    outs() << "  Testing after loop extraction:\n";
    // Clone modules, the tester function will free them.
    Module *TOLEBackup = CloneModule(ToOptimizeLoopExtracted);
    Module *TNOBackup  = CloneModule(ToNotOptimize);
    Failure = TestFn(BD, ToOptimizeLoopExtracted, ToNotOptimize, Error);
    if (!Error.empty())
      return false;
    if (!Failure) {
      outs() << "*** Loop extraction masked the problem.  Undoing.\n";
      // If the program is not still broken, then loop extraction did something
      // that masked the error.  Stop loop extraction now.
      delete TOLEBackup;
      delete TNOBackup;
      return MadeChange;
    }
    ToOptimizeLoopExtracted = TOLEBackup;
    ToNotOptimize = TNOBackup;

    outs() << "*** Loop extraction successful!\n";

    std::vector<std::pair<std::string, const FunctionType*> > MisCompFunctions;
    for (Module::iterator I = ToOptimizeLoopExtracted->begin(),
           E = ToOptimizeLoopExtracted->end(); I != E; ++I)
      if (!I->isDeclaration())
        MisCompFunctions.push_back(std::make_pair(I->getName(),
                                                  I->getFunctionType()));

    // Okay, great!  Now we know that we extracted a loop and that loop
    // extraction both didn't break the program, and didn't mask the problem.
    // Replace the current program with the loop extracted version, and try to
    // extract another loop.
    std::string ErrorMsg;
    if (Linker::LinkModules(ToNotOptimize, ToOptimizeLoopExtracted, &ErrorMsg)){
      errs() << BD.getToolName() << ": Error linking modules together:"
             << ErrorMsg << '\n';
      exit(1);
//.........这里部分代码省略.........

/// ExtractBlocks - Given a reduced list of functions that still expose the bug,
/// extract as many basic blocks from the region as possible without obscuring
/// the bug.
///
static bool ExtractBlocks(BugDriver &BD,
                          bool (*TestFn)(BugDriver &, Module *, Module *,
                                         std::string &),
                          std::vector<Function*> &MiscompiledFunctions,
                          std::string &Error) {
  if (BugpointIsInterrupted) return false;
  
  std::vector<BasicBlock*> Blocks;
  for (unsigned i = 0, e = MiscompiledFunctions.size(); i != e; ++i)
    for (Function::iterator I = MiscompiledFunctions[i]->begin(),
           E = MiscompiledFunctions[i]->end(); I != E; ++I)
      Blocks.push_back(I);

  // Use the list reducer to identify blocks that can be extracted without
  // obscuring the bug.  The Blocks list will end up containing blocks that must
  // be retained from the original program.
  unsigned OldSize = Blocks.size();

  // Check to see if all blocks are extractible first.
  bool Ret = ReduceMiscompiledBlocks(BD, TestFn, MiscompiledFunctions)
                                  .TestFuncs(std::vector<BasicBlock*>(), Error);
  if (!Error.empty())
    return false;
  if (Ret) {
    Blocks.clear();
  } else {
    ReduceMiscompiledBlocks(BD, TestFn,
                            MiscompiledFunctions).reduceList(Blocks, Error);
    if (!Error.empty())
      return false;
    if (Blocks.size() == OldSize)
      return false;
  }

  DenseMap<const Value*, Value*> ValueMap;
  Module *ProgClone = CloneModule(BD.getProgram(), ValueMap);
  Module *ToExtract = SplitFunctionsOutOfModule(ProgClone,
                                                MiscompiledFunctions,
                                                ValueMap);
  Module *Extracted = BD.ExtractMappedBlocksFromModule(Blocks, ToExtract);
  if (Extracted == 0) {
    // Weird, extraction should have worked.
    errs() << "Nondeterministic problem extracting blocks??\n";
    delete ProgClone;
    delete ToExtract;
    return false;
  }

  // Otherwise, block extraction succeeded.  Link the two program fragments back
  // together.
  delete ToExtract;

  std::vector<std::pair<std::string, const FunctionType*> > MisCompFunctions;
  for (Module::iterator I = Extracted->begin(), E = Extracted->end();
       I != E; ++I)
    if (!I->isDeclaration())
      MisCompFunctions.push_back(std::make_pair(I->getName(),
                                                I->getFunctionType()));

  std::string ErrorMsg;
  if (Linker::LinkModules(ProgClone, Extracted, &ErrorMsg)) {
    errs() << BD.getToolName() << ": Error linking modules together:"
           << ErrorMsg << '\n';
    exit(1);
  }
  delete Extracted;

  // Set the new program and delete the old one.
  BD.setNewProgram(ProgClone);

  // Update the list of miscompiled functions.
  MiscompiledFunctions.clear();

  for (unsigned i = 0, e = MisCompFunctions.size(); i != e; ++i) {
    Function *NewF = ProgClone->getFunction(MisCompFunctions[i].first);
    assert(NewF && "Function not found??");
    assert(NewF->getFunctionType() == MisCompFunctions[i].second && 
           "Function has wrong type??");
    MiscompiledFunctions.push_back(NewF);
  }

  return true;
}

/*!
 *  This method identify which is value sym and which is object sym
 */
void SymbolTableInfo::buildMemModel(llvm::Module& module) {
    analysisUtil::increaseStackSize();

    prePassSchedule(module);

    mod = &module;

    maxFieldLimit = maxFieldNumLimit;

    // Object #0 is black hole the object that may point to any object
    assert(totalSymNum == BlackHole && "Something changed!");
    symTyMap.insert(std::make_pair(totalSymNum++, BlackHole));
    createBlkOrConstantObj(BlackHole);

    // Object #1 always represents the constant
    assert(totalSymNum == ConstantObj && "Something changed!");
    symTyMap.insert(std::make_pair(totalSymNum++, ConstantObj));
    createBlkOrConstantObj(ConstantObj);

    // Pointer #2 always represents the pointer points-to black hole.
    assert(totalSymNum == BlkPtr && "Something changed!");
    symTyMap.insert(std::make_pair(totalSymNum++, BlkPtr));

    // Pointer #3 always represents the null pointer.
    assert(totalSymNum == NullPtr && "Something changed!");
    symTyMap.insert(std::make_pair(totalSymNum, NullPtr));

    // Add symbols for all the globals .
    for (Module::global_iterator I = module.global_begin(), E =
                module.global_end(); I != E; ++I) {
        collectSym(&*I);
    }

    // Add symbols for all the global aliases
    for (Module::alias_iterator I = module.alias_begin(), E =
                module.alias_end(); I != E; I++) {
        collectSym(&*I);
    }

    // Add symbols for all of the functions and the instructions in them.
    for (Module::iterator F = module.begin(), E = module.end(); F != E; ++F) {
        collectSym(&*F);
        collectRet(&*F);
        if (F->getFunctionType()->isVarArg())
            collectVararg(&*F);

        // Add symbols for all formal parameters.
        for (Function::arg_iterator I = F->arg_begin(), E = F->arg_end();
                I != E; ++I) {
            collectSym(&*I);
        }

        // collect and create symbols inside the function body
        for (inst_iterator II = inst_begin(&*F), E = inst_end(&*F); II != E; ++II) {
            const Instruction *inst = &*II;
            collectSym(inst);

            // initialization for some special instructions
            //{@
            if (const StoreInst *st = dyn_cast<StoreInst>(inst)) {
                collectSym(st->getPointerOperand());
                collectSym(st->getValueOperand());
            }

            else if (const LoadInst *ld = dyn_cast<LoadInst>(inst)) {
                collectSym(ld->getPointerOperand());
            }

            else if (const PHINode *phi = dyn_cast<PHINode>(inst)) {
                for (u32_t i = 0; i < phi->getNumIncomingValues(); ++i) {
                    collectSym(phi->getIncomingValue(i));
                }
            }

            else if (const GetElementPtrInst *gep = dyn_cast<GetElementPtrInst>(
                    inst)) {
                collectSym(gep->getPointerOperand());
            }

            else if (const SelectInst *sel = dyn_cast<SelectInst>(inst)) {
                collectSym(sel->getTrueValue());
                collectSym(sel->getFalseValue());
            }

            else if (const CastInst *cast = dyn_cast<CastInst>(inst)) {
                collectSym(cast->getOperand(0));
            }
            else if (const ReturnInst *ret = dyn_cast<ReturnInst>(inst)) {
                if(ret->getReturnValue())
                    collectSym(ret->getReturnValue());
            }
            else if (isCallSite(inst) && isInstrinsicDbgInst(inst)==false) {

                CallSite cs = analysisUtil::getLLVMCallSite(inst);
                callSiteSet.insert(cs);
                for (CallSite::arg_iterator it = cs.arg_begin();
                        it != cs.arg_end(); ++it) {
//.........这里部分代码省略.........