C++ module::iterator类代码示例

/// DisambiguateGlobalSymbols - Mangle symbols to guarantee uniqueness by
/// modifying predominantly internal symbols rather than external ones.
///
static void DisambiguateGlobalSymbols(Module *M) {
  // Try not to cause collisions by minimizing chances of renaming an
  // already-external symbol, so take in external globals and functions as-is.
  // The code should work correctly without disambiguation (assuming the same
  // mangler is used by the two code generators), but having symbols with the
  // same name causes warnings to be emitted by the code generator.
  Mangler Mang(*M);
  // Agree with the CBE on symbol naming
  Mang.markCharUnacceptable('.');
  Mang.setPreserveAsmNames(true);
  for (Module::global_iterator I = M->global_begin(), E = M->global_end();
       I != E; ++I)
    I->setName(Mang.getValueName(I));
  for (Module::iterator  I = M->begin(),  E = M->end();  I != E; ++I)
    I->setName(Mang.getValueName(I));
}

void Preparer::replaceUndefsWithNull(Module &M) {
  ValueSet Replaced;
  for (Module::global_iterator GI = M.global_begin(); GI != M.global_end();
       ++GI) {
    if (GI->hasInitializer()) {
      replaceUndefsWithNull(GI->getInitializer(), Replaced);
    }
  }
  for (Module::iterator F = M.begin(); F != M.end(); ++F) {
    for (Function::iterator BB = F->begin(); BB != F->end(); ++BB) {
      for (BasicBlock::iterator Ins = BB->begin(); Ins != BB->end(); ++Ins) {
        replaceUndefsWithNull(Ins, Replaced);
      }
    }
  }
}

// StripDebugInfo - Strip debug info in the module if it exists.  
// To do this, we remove llvm.dbg.func.start, llvm.dbg.stoppoint, and 
// llvm.dbg.region.end calls, and any globals they point to if now dead.
static bool StripDebugInfo(Module &M) {

  bool Changed = false;

  // Remove all of the calls to the debugger intrinsics, and remove them from
  // the module.
  if (Function *Declare = M.getFunction("llvm.dbg.declare")) {
    while (!Declare->use_empty()) {
      CallInst *CI = cast<CallInst>(Declare->use_back());
      CI->eraseFromParent();
    }
    Declare->eraseFromParent();
    Changed = true;
  }

  if (Function *DbgVal = M.getFunction("llvm.dbg.value")) {
    while (!DbgVal->use_empty()) {
      CallInst *CI = cast<CallInst>(DbgVal->use_back());
      CI->eraseFromParent();
    }
    DbgVal->eraseFromParent();
    Changed = true;
  }

  for (Module::named_metadata_iterator NMI = M.named_metadata_begin(),
         NME = M.named_metadata_end(); NMI != NME;) {
    NamedMDNode *NMD = NMI;
    ++NMI;
    if (NMD->getName().startswith("llvm.dbg.")) {
      NMD->eraseFromParent();
      Changed = true;
    }
  }

  for (Module::iterator MI = M.begin(), ME = M.end(); MI != ME; ++MI)
    for (Function::iterator FI = MI->begin(), FE = MI->end(); FI != FE;
         ++FI)
      for (BasicBlock::iterator BI = FI->begin(), BE = FI->end(); BI != BE;
           ++BI) {
        if (!BI->getDebugLoc().isUnknown()) {
          Changed = true;
          BI->setDebugLoc(DebugLoc());
        }
      }

  return Changed;
}

bool MipsOs16::runOnModule(Module &M) {
  DEBUG(errs() << "Run on Module MipsOs16\n");
  bool modified = false;
  for (Module::iterator F = M.begin(), E = M.end(); F != E; ++F) {
    if (F->isDeclaration()) continue;
    DEBUG(dbgs() << "Working on " << F->getName() << "\n");
    if (needsFP(*F)) {
      DEBUG(dbgs() << " need to compile as nomips16 \n");
      F->addFnAttr("nomips16");
    }
    else {
      F->addFnAttr("mips16");
      DEBUG(dbgs() << " no need to compile as nomips16 \n");
    }
  }
  return modified;
}

// Unfortunately, the LLVM C API doesn't provide an easy way of iterating over
// all the functions in a module, so we do that manually here. You'll find
// similar code in clang's BackendUtil.cpp file.
extern "C" void
LLVMRustRunFunctionPassManager(LLVMPassManagerRef PM, LLVMModuleRef M) {
    llvm::legacy::FunctionPassManager *P = unwrap<llvm::legacy::FunctionPassManager>(PM);
    P->doInitialization();

    // Upgrade all calls to old intrinsics first.
    for (Module::iterator I = unwrap(M)->begin(),
         E = unwrap(M)->end(); I != E;)
        UpgradeCallsToIntrinsic(&*I++); // must be post-increment, as we remove

    for (Module::iterator I = unwrap(M)->begin(),
         E = unwrap(M)->end(); I != E; ++I)
        if (!I->isDeclaration())
            P->run(*I);

    P->doFinalization();
}

bool IDManager::runOnModule(Module &M) {
	IDMapping.clear();
	for (Module::iterator F = M.begin(); F != M.end(); ++F) {
		for (Function::iterator B = F->begin(); B != F->end(); ++B) {
			for (BasicBlock::iterator I = B->begin(); I != B->end(); ++I) {
				unsigned InsID = getInstructionID(I);
				if (InsID != INVALID_ID)
					IDMapping[InsID].push_back(I);
			}
		}
	}

	if (size() == 0)
		errs() << "[Warning] No ID information in this program.\n";

	return false;
}

/// findFunctionScopedAllocas - store all allocas that are known to be valid
/// to the end of their function in a set. The current algorithm does this by
/// finding all the allocas in the entry block that are before the first
/// llvm.stacksave call (if any).
///
/// FIXME: There can also be allocas elsewhere that get deallocated at the end
/// of the function but they are pessimistically ignored for now.
///
void ExactCheckOpt::findFunctionScopedAllocas(Module &M) {
  for (Module::iterator F = M.begin(), E = M.end(); F != E; ++F) {
    if (F->empty())
      continue;

    BasicBlock &BB = F->getEntryBlock();
    for (BasicBlock::iterator I = BB.begin(), E = BB.end(); I != E; ++I) {
      if (AllocaInst *AI = dyn_cast<AllocaInst>(I)) {
        FunctionScopedAllocas.insert(AI);
      } else if(CallInst *CI = dyn_cast<CallInst>(I)) {
        Function *CalledFunction = CI->getCalledFunction();
        if (CalledFunction && CalledFunction->getName() == "llvm.stacksave")
          break;
      }
    }
  }
}

/// deleteInstructionFromProgram - This method clones the current Program and
/// deletes the specified instruction from the cloned module.  It then runs a
/// series of cleanup passes (ADCE and SimplifyCFG) to eliminate any code which
/// depends on the value.  The modified module is then returned.
///
Module *BugDriver::deleteInstructionFromProgram(const Instruction *I,
                                                unsigned Simplification) const {
  Module *Result = CloneModule(Program);

  const BasicBlock *PBB = I->getParent();
  const Function *PF = PBB->getParent();

  Module::iterator RFI = Result->begin(); // Get iterator to corresponding fn
  std::advance(RFI, std::distance(PF->getParent()->begin(),
                                  Module::const_iterator(PF)));

  Function::iterator RBI = RFI->begin();  // Get iterator to corresponding BB
  std::advance(RBI, std::distance(PF->begin(), Function::const_iterator(PBB)));

  BasicBlock::iterator RI = RBI->begin(); // Get iterator to corresponding inst
  std::advance(RI, std::distance(PBB->begin(), BasicBlock::const_iterator(I)));
  Instruction *TheInst = RI;              // Got the corresponding instruction!

  // If this instruction produces a value, replace any users with null values
  if (isa<StructType>(TheInst->getType()))
    TheInst->replaceAllUsesWith(UndefValue::get(TheInst->getType()));
  else if (TheInst->getType() != Type::getVoidTy(I->getContext()))
    TheInst->replaceAllUsesWith(Constant::getNullValue(TheInst->getType()));

  // Remove the instruction from the program.
  TheInst->getParent()->getInstList().erase(TheInst);

  
  //writeProgramToFile("current.bc", Result);
    
  // Spiff up the output a little bit.
  PassManager Passes;
  // Make sure that the appropriate target data is always used...
  Passes.add(new TargetData(Result));

  /// FIXME: If this used runPasses() like the methods below, we could get rid
  /// of the -disable-* options!
  if (Simplification > 1 && !NoDCE)
    Passes.add(createDeadCodeEliminationPass());
  if (Simplification && !DisableSimplifyCFG)
    Passes.add(createCFGSimplificationPass());      // Delete dead control flow

  Passes.add(createVerifierPass());
  Passes.run(*Result);
  return Result;
}

// Check the assumptions we made.
void CheckInserter::checkFeatures(Module &M) {
  // Assume no function name starts with Loom.
  for (Module::iterator F = M.begin(); F != M.end(); ++F) {
    assert(!F->getName().startswith("Loom") &&
           "Loom update engine seems already instrumented");
  }
  // We do not support the situation where some important functions are called
  // via a function pointer, e.g. pthread_create, pthread_join and fork.
  for (Module::iterator F = M.begin(); F != M.end(); ++F) {
    if (F->getName() == "pthread_create" ||
        F->getName() == "pthread_join" ||
        F->getName() == "fork") {
      for (Value::use_iterator UI = F->use_begin(); UI != F->use_end(); ++UI) {
        User *Usr = *UI;
        assert(isa<CallInst>(Usr) || isa<InvokeInst>(Usr));
        CallSite CS(cast<Instruction>(Usr));
        for (unsigned i = 0; i < CS.arg_size(); ++i)
          assert(CS.getArgument(i) != F);
      }
    }
  }
  // pthread_cancel provides another way of terminating a thread, which we have
  // not supported yet.
  assert(M.getFunction("pthread_cancel") == NULL);
}

/// Emit extern decls for functions imported from other modules, and emit
/// global declarations for function defined in this module and which are
/// available to other modules.
///
void PIC16AsmPrinter::EmitFunctionDecls(Module &M) {
 // Emit declarations for external functions.
  O <<"\n"<<MAI->getCommentString() << "Function Declarations - BEGIN." <<"\n";
  for (Module::iterator I = M.begin(), E = M.end(); I != E; I++) {
    if (I->isIntrinsic() || I->getName() == "@abort")
      continue;
    
    if (!I->isDeclaration() && !I->hasExternalLinkage())
      continue;

    MCSymbol *Sym = Mang->getSymbol(I);
    
    // Do not emit memcpy, memset, and memmove here.
    // Calls to these routines can be generated in two ways,
    // 1. User calling the standard lib function
    // 2. Codegen generating these calls for llvm intrinsics.
    // In the first case a prototype is alread availale, while in
    // second case the call is via and externalsym and the prototype is missing.
    // So declarations for these are currently always getting printing by
    // tracking both kind of references in printInstrunction.
    if (I->isDeclaration() && PAN::isMemIntrinsic(Sym->getName())) continue;

    const char *directive = I->isDeclaration() ? MAI->getExternDirective() :
                                                 MAI->getGlobalDirective();
      
    O << directive << Sym->getName() << "\n";
    O << directive << PAN::getRetvalLabel(Sym->getName()) << "\n";
    O << directive << PAN::getArgsLabel(Sym->getName()) << "\n";
  }

  O << MAI->getCommentString() << "Function Declarations - END." <<"\n";
}

bool DivCheckPass::runOnModule(Module &M) { 
  Function *divZeroCheckFunction = 0;
  LLVMContext &ctx = M.getContext();

  bool moduleChanged = false;
  
  for (Module::iterator f = M.begin(), fe = M.end(); f != fe; ++f) {
    for (Function::iterator b = f->begin(), be = f->end(); b != be; ++b) {
      for (BasicBlock::iterator i = b->begin(), ie = b->end(); i != ie; ++i) {     
          if (BinaryOperator* binOp = dyn_cast<BinaryOperator>(i)) {
          // find all [s|u][div|mod] instructions
          Instruction::BinaryOps opcode = binOp->getOpcode();
          if (opcode == Instruction::SDiv || opcode == Instruction::UDiv ||
              opcode == Instruction::SRem || opcode == Instruction::URem) {
            
            CastInst *denominator =
              CastInst::CreateIntegerCast(i->getOperand(1),
                                          Type::getInt64Ty(ctx),
                                          false,  /* sign doesn't matter */
                                          "int_cast_to_i64",
                                          &*i);
            
            // Lazily bind the function to avoid always importing it.
            if (!divZeroCheckFunction) {
              Constant *fc = M.getOrInsertFunction("klee_div_zero_check", 
                                                   Type::getVoidTy(ctx),
                                                   Type::getInt64Ty(ctx),
                                                   NULL);
              divZeroCheckFunction = cast<Function>(fc);
            }

            CallInst * ci = CallInst::Create(divZeroCheckFunction, denominator, "", &*i);

            // Set debug location of checking call to that of the div/rem
            // operation so error locations are reported in the correct
            // location.
            ci->setDebugLoc(binOp->getDebugLoc());
            moduleChanged = true;
          }
        }
      }
    }
  }
  return moduleChanged;
}

bool ExpandByVal::runOnModule(Module &M) {
  bool Modified = false;
  DataLayout DL(&M);

  for (Module::iterator Func = M.begin(), E = M.end(); Func != E; ++Func) {
    AttributeSet NewAttrs = RemoveAttrs(Func->getContext(),
                                        Func->getAttributes());
    Modified |= (NewAttrs != Func->getAttributes());
    Func->setAttributes(NewAttrs);

    for (Function::iterator BB = Func->begin(), E = Func->end();
         BB != E; ++BB) {
      for (BasicBlock::iterator Inst = BB->begin(), E = BB->end();
           Inst != E; ++Inst) {
        if (CallInst *Call = dyn_cast<CallInst>(Inst)) {
          Modified |= ExpandCall(&DL, Call);
        } else if (InvokeInst *Call = dyn_cast<InvokeInst>(Inst)) {
          Modified |= ExpandCall(&DL, Call);
        }
      }
    }
  }

  return Modified;
}

bool llvm::InputValues::runOnModule(Module& M) {

	module = &M;

	initializeWhiteList();

    collectMainArguments();

	for(Module::iterator Fit = M.begin(), Fend = M.end(); Fit != Fend; Fit++){

		for (Function::iterator BBit = Fit->begin(), BBend = Fit->end(); BBit != BBend; BBit++) {

			for (BasicBlock::iterator Iit = BBit->begin(), Iend = BBit->end(); Iit != Iend; Iit++) {

				if (CallInst *CI = dyn_cast<CallInst>(Iit)) {

					if (isMarkedCallInst(CI)){

						//Values returned by marked instructions
						insertInInputDepValues(CI);

						for(unsigned int i = 0; i < CI->getNumOperands(); i++){

							if (CI->getOperand(i)->getType()->isPointerTy()){
								//Arguments with pointer type of marked functions
								insertInInputDepValues(CI->getOperand(i));
							}

						}

					}

				}

			}

		}

	}

	NumInputValues = inputValues.size();

	//We don't modify anything, so we must return false;
	return false;
}

std::unique_ptr<Module>
BugDriver::deleteInstructionFromProgram(const Instruction *I,
                                        unsigned Simplification) {
  // FIXME, use vmap?
  Module *Clone = CloneModule(Program);

  const BasicBlock *PBB = I->getParent();
  const Function *PF = PBB->getParent();

  Module::iterator RFI = Clone->begin(); // Get iterator to corresponding fn
  std::advance(RFI, std::distance(PF->getParent()->begin(),
                                  Module::const_iterator(PF)));

  Function::iterator RBI = RFI->begin();  // Get iterator to corresponding BB
  std::advance(RBI, std::distance(PF->begin(), Function::const_iterator(PBB)));

  BasicBlock::iterator RI = RBI->begin(); // Get iterator to corresponding inst
  std::advance(RI, std::distance(PBB->begin(), BasicBlock::const_iterator(I)));
  Instruction *TheInst = RI;              // Got the corresponding instruction!

  // If this instruction produces a value, replace any users with null values
  if (!TheInst->getType()->isVoidTy())
    TheInst->replaceAllUsesWith(Constant::getNullValue(TheInst->getType()));

  // Remove the instruction from the program.
  TheInst->getParent()->getInstList().erase(TheInst);

  // Spiff up the output a little bit.
  std::vector<std::string> Passes;

  /// Can we get rid of the -disable-* options?
  if (Simplification > 1 && !NoDCE)
    Passes.push_back("dce");
  if (Simplification && !DisableSimplifyCFG)
    Passes.push_back("simplifycfg");      // Delete dead control flow

  Passes.push_back("verify");
  std::unique_ptr<Module> New = runPassesOn(Clone, Passes);
  delete Clone;
  if (!New) {
    errs() << "Instruction removal failed.  Sorry. :(  Please report a bug!\n";
    exit(1);
  }
  return New;
}

bool StripAttributes::runOnModule(Module &M) {
  DataLayout DL(&M);
  for (Module::iterator Func = M.begin(), E = M.end(); Func != E; ++Func) {
    // Avoid stripping attributes from intrinsics because the
    // constructor for Functions just adds them back again.  It would
    // be confusing if the attributes were sometimes present on
    // intrinsics and sometimes not.
    if (!Func->isIntrinsic()) {
      stripGlobalValueAttrs(Func);
      stripFunctionAttrs(&DL, Func);
    }
  }
  for (Module::global_iterator GV = M.global_begin(), E = M.global_end();
       GV != E; ++GV) {
    stripGlobalValueAttrs(GV);
  }
  return true;
}