Beispiel #1
0
/** 
 * class: SgArrayType
 * term: array_type(nested,index)
 * arg nested: nested type
 * arg index: index (a SgExpression)
 */
PrologCompTerm* 
RoseToTerm::getArrayTypeSpecific(SgType* mtype) {
  /*make sure we are actually dealing with an array type*/
  SgArrayType* a = isSgArrayType(mtype);
  ROSE_ASSERT(a != NULL);
  return new PrologCompTerm
    ("array_type", //2,
     getTypeSpecific(a->get_base_type()), /* get nested type*/ 
     (a->get_index() /* get expression*/
      ? traverseSingleNode(a->get_index())
      : new PrologAtom("null")));
}
Beispiel #2
0
void examineType(SgType *type, ostream &out) {
    int nr_stars = 0;
    stringstream ss1;
    if (NULL == type) {
        out << "void";
        return;
    }
    while (isSgArrayType(type) ||
            isSgPointerType(type)) {
        if (isSgArrayType(type)) {
            SgArrayType *atype = isSgArrayType(type);
            SgExpression *expr = atype->get_index();

            type = atype->get_base_type();
            /*
            ss1 << "[";
            if (expr)
                examineExpr(expr, ss1);
            ss1 << "]";
            */
            nr_stars++;
        } else {
            SgPointerType *ttype = isSgPointerType(type);
            type = ttype->get_base_type();
            nr_stars++;
        }
    }

    examinePrimTypeName(type, out);
    out << " ";
    for (int i = 0; i < nr_stars; ++i)
        out << "*";
    out << ss1.str();
}
InheritedAttribute
BugSeeding::evaluateInheritedAttribute (
     SgNode* astNode,
     InheritedAttribute inheritedAttribute )
   {
  // Use this if we only want to seed bugs in loops
     bool isLoop = inheritedAttribute.isLoop           ||
                   (isSgForStatement(astNode) != NULL) ||
                   (isSgWhileStmt(astNode) != NULL)    ||
                   (isSgDoWhileStmt(astNode) != NULL);
  // Add Fortran support
     isLoop = isLoop || (isSgFortranDo(astNode) != NULL);

  // Mark future noes in this subtree as being part of a loop
     inheritedAttribute.isLoop = isLoop;

  // To test this on simple codes, optionally allow it to be applied everywhere
     bool applyEveryWhere = true;

     if (isLoop == true || applyEveryWhere == true)
        {
       // The inherited attribute is true iff we are inside a loop and this is a SgPntrArrRefExp.
          SgPntrArrRefExp *arrayReference = isSgPntrArrRefExp(astNode);
          if (arrayReference != NULL)
             {
            // Mark as a vulnerability
               inheritedAttribute.isVulnerability = true;

            // Now change the array index (to seed the buffer overflow bug)
               SgVarRefExp* arrayVarRef = isSgVarRefExp(arrayReference->get_lhs_operand());
               ROSE_ASSERT(arrayVarRef != NULL);
               ROSE_ASSERT(arrayVarRef->get_symbol() != NULL);
               SgInitializedName* arrayName = isSgInitializedName(arrayVarRef->get_symbol()->get_declaration());
               ROSE_ASSERT(arrayName != NULL);
               SgArrayType* arrayType = isSgArrayType(arrayName->get_type());
               ROSE_ASSERT(arrayType != NULL);
               SgExpression* arraySize = arrayType->get_index();

               SgTreeCopy copyHelp;
            // Make a copy of the expression used to hold the array size in the array declaration.
               SgExpression* arraySizeCopy = isSgExpression(arraySize->copy(copyHelp));
               ROSE_ASSERT(arraySizeCopy != NULL);

            // This is the existing index expression
               SgExpression* indexExpression = arrayReference->get_rhs_operand();
               ROSE_ASSERT(indexExpression != NULL);

            // Build a new expression: "array[n]" --> "array[n+arraySizeCopy]", where the arraySizeCopy is a size of "array"
               SgExpression* newIndexExpression = buildAddOp(indexExpression,arraySizeCopy);

            // Substitute the new expression for the old expression
               arrayReference->set_rhs_operand(newIndexExpression);
             }
        }

     return inheritedAttribute;
   }
Beispiel #4
0
void examineInitializedName(SgInitializedName *name, ostream &out) {
    SgSymbol* symbol = name->get_symbol_from_symbol_table();
    if (NULL == symbol)
        return;
    SgType *type = symbol->get_type();
    int nr_stars = 0;
    stringstream ss1;
    
    while (isSgArrayType(type) ||
            isSgPointerType(type)) {
        if (isSgArrayType(type)) {
            SgArrayType *atype = isSgArrayType(type);
            SgExpression *expr = atype->get_index();

            type = atype->get_base_type();
            ss1 << "[";
            if (expr)
                examineExpr(expr, ss1);
            ss1 << "]";
        } else {
            SgPointerType *ttype = isSgPointerType(type);
            type = ttype->get_base_type();
            nr_stars++;
        }
    }
    examinePrimTypeName(type, out);
    out << " ";
    for (int i = 0; i < nr_stars; ++i)
        out << "*";
    out << symbol->get_name().getString();
    out << ss1.str();

    SgInitializer *initer = name->get_initializer();
    if (initer) {
        switch (initer->variantT()) {
            case V_SgAssignInitializer:
                SgAssignInitializer *ai = isSgAssignInitializer(initer);
                SgExpression *expr = ai->get_operand();
                if (expr) {
                    out << "=";
                    examineExpr(expr, out);
                }
                break;
            default:
                break;
        }
    }
}
Beispiel #5
0
void
DetectHiddenOriginalExpressionTreeTraversal::visit ( SgNode* node )
   {
  // We only want to search for original expression trees where they can be hidden.

     ROSE_ASSERT(node != NULL);

     SgArrayType* arrayType = isSgArrayType(node);
     if (arrayType != NULL)
        {
#if 0
          printf ("Found an array type arrayType = %p (looking for original expression tree) \n",arrayType);
#endif
          SgExpression* index = arrayType->get_index();
          if (index != NULL)
             {
               DetectOriginalExpressionTreeTraversal t;
               t.traverse(index,preorder);
             }
        }

#if 0
  // DQ (9/18/2011): This code will not work since the bitfile data member in SgVariableDefinition is a SgUnsignedLongVal instead of a SgExpression.
     SgVariableDefinition* variableDefinition = isSgVariableDefinition(node);
     if (variableDefinition != NULL)
        {
#if 0
          printf ("Found a SgVariableDefinition (looking for original expression tree) \n");
#endif
          SgExpression* bitfieldExp = variableDefinition->get_bitfield();
          if (bitfieldExp != NULL)
             {
               DetectOriginalExpressionTreeTraversal t;
               t.traverse(bitfieldExp,preorder);
             }
        }
#endif
   }
Beispiel #6
0
void
RemoveConstantFoldedValueViaParent::visit ( SgNode* node )
   {
  // This is an alternative implementation that allows us to handle expression that are not 
  // traversed in the AST (e.g. types like SgArrayType which can contain expressions).

     ROSE_ASSERT(node != NULL);

  // DQ (3/11/2006): Set NULL pointers where we would like to have none.
#if 0
     printf ("In RemoveConstantFoldedValueViaParent::visit(): node = %p = %s \n",node,node->class_name().c_str());
#endif

  // DQ (10/12/2012): Turn this on so that we can detect failing IR nodes (failing later) that have valid originalExpressionTrees.
  // DQ (10/12/2012): Turn this back off because it appears to fail...
#if 0
     SgExpression* exp = isSgExpression(node);
     if (exp != NULL)
        {
          SgExpression* originalExpressionTree = exp->get_originalExpressionTree();
          if (originalExpressionTree != NULL)
             {
               SgNode* parent = exp->get_parent();
               if (parent != NULL)
                  {
                    printf ("Current IR node with SgExpression parent = %p = %s child = %p = %s originalExpressionTree = %p = %s \n",parent,parent->class_name().c_str(),node,node->class_name().c_str(),originalExpressionTree,originalExpressionTree->class_name().c_str());
                    bool traceReplacement = true;
                    ConstantFoldedValueReplacer r(traceReplacement, exp);
                    parent->processDataMemberReferenceToPointers(&r);
                 // node->processDataMemberReferenceToPointers(&r);
                  }

            // Set the originalExpressionTree to NULL.
               exp->set_originalExpressionTree(NULL);

            // Set the parent of originalExpressionTree to be the parent of exp.
               originalExpressionTree->set_parent(parent);

            // And then delete the folded constant.
               SageInterface::deleteAST(exp);
             }
        }
#endif

     SgArrayType* arrayType = isSgArrayType(node);
     if (arrayType != NULL)
        {
#if 0
          printf ("Found an array type arrayType = %p arrayType->get_index() = %p \n",arrayType,arrayType->get_index());
#endif
          SgExpression* index = arrayType->get_index();
          if (index != NULL)
             {
#if 0
               printf ("Fixup array index = %p = %s (traverse index AST subtree) \n",index,index->class_name().c_str());
#endif
               RemoveConstantFoldedValue astFixupTraversal;
               astFixupTraversal.traverse(index);
#if 0
               printf ("DONE: Fixup array index = %p (traverse index AST) \n\n\n\n",index);
#endif
#if 0
               printf ("Found an array index = %p (fixup index directly) \n",index);
#endif
            // Handle the case where the original expression tree is at the root of the subtree.
               SgExpression* originalExpressionTree = index->get_originalExpressionTree();
               if (originalExpressionTree != NULL)
                  {
#if 0
                    printf ("Found an originalExpressionTree in the array index originalExpressionTree = %p \n",originalExpressionTree);
#endif
                 // DQ (6/12/2013): This appears to be a problem in EDG 4.7 (see test2011_117.C).
                    std::vector<SgExpression*> redundantChainOfOriginalExpressionTrees;
                    if (originalExpressionTree->get_originalExpressionTree() != NULL)
                       {
#if 0
                         printf ("Detected originalExpressionTree nested directly within the originalExpressionTree \n",
                              originalExpressionTree,originalExpressionTree->class_name().c_str(),
                              originalExpressionTree->get_originalExpressionTree(),originalExpressionTree->get_originalExpressionTree()->class_name().c_str());
#endif
                      // Loop to the end of the chain of original expressions (which EDG 4.7 should never have constructed).
                         while (originalExpressionTree->get_originalExpressionTree() != NULL)
                            {
#if 0
                              printf ("Looping through a chain of originalExpressionTrees \n");
#endif
                           // Save the list of redundnat nodes so that we can delete them properly.
                              redundantChainOfOriginalExpressionTrees.push_back(originalExpressionTree);

                              originalExpressionTree = originalExpressionTree->get_originalExpressionTree();
                            }
#if 0
                         printf ("Exiting as a test! \n");
                         ROSE_ASSERT(false);
#endif
                       }

                    arrayType->set_index(originalExpressionTree);
                    originalExpressionTree->set_parent(arrayType);

                    index->set_originalExpressionTree(NULL);

                 // printf ("DEBUGING: skip delete of index in array type \n");
                    delete index;

                 // DQ (6/12/2013): Delete the nodes that we had to skip over (caused by chain of redundant entries from EDG 4.7).
                    std::vector<SgExpression*>::iterator i = redundantChainOfOriginalExpressionTrees.begin();
                    while (i != redundantChainOfOriginalExpressionTrees.end())
                       {
#if 0
                         printf ("deleting the redundnat originalExpressionTree chain caused by EDG 4.7 (delete %p = %s) \n",*i,(*i)->class_name().c_str());
#endif
                         delete *i;
                         i++;
                       }

                    index = NULL;
                  }
             }
        }

     SgVariableDefinition* variableDefinition = isSgVariableDefinition(node);
     if (variableDefinition != NULL)
        {
#if 0
          printf ("Found a SgVariableDefinition \n");
#endif
          SgExpression* bitfieldExp = variableDefinition->get_bitfield();
          if (bitfieldExp != NULL)
             {
#if 0
               printf ("Fixup bitfieldExp = %p (traverse bitfieldExp AST subtree) \n",bitfieldExp);
#endif
               RemoveConstantFoldedValue astFixupTraversal;
               astFixupTraversal.traverse(bitfieldExp);

            // Handle the case where the original expression tree is at the root of the subtree.
               SgExpression* originalExpressionTree = bitfieldExp->get_originalExpressionTree();
               if (originalExpressionTree != NULL)
                  {
#if 0
                 // DQ (9/18/2011): This code will not work since the bitfile data member in SgVariableDefinition is a SgUnsignedLongVal instead of a SgExpression.
                    variableDefinition->set_bitfield(originalExpressionTree);
                    originalExpressionTree->set_parent(variableDefinition);

                    bitfieldExp->set_originalExpressionTree(NULL);
                    delete bitfieldExp;
                    bitfieldExp = NULL;
#else
                 // The ROSE AST needs to be fixed to handle more general expressions for bitfield widths (this does not effect the CFG).
                 // TODO: Change the data type of the bitfield data member in SgVariableDefinition.

                 // DQ (1/20/2014): This has been done now.
                 // printf ("Member data bitfield widths need to be changed (in the ROSE IR) to support more general expressions (can't fix this original expression tree) \n");
#endif
#if 0
                 // This case is not handled yet!
                    printf ("Found an original expression tree in a bitfield expression \n");
                    ROSE_ASSERT(false);
#endif
                  }
             }
        }
   }
Beispiel #7
0
ExprSynAttr *examineVariableDeclaration(SgVariableDeclaration* decl, ostream &out) {
  SgInitializedNamePtrList& name_list = decl->get_variables();
  SgInitializedNamePtrList::const_iterator name_iter;
  ExprSynAttr *ret = NULL;
  ExprSynAttr *gc = NULL;
  ret = new ExprSynAttr();
  for (name_iter = name_list.begin(); 
       name_iter != name_list.end(); 
       name_iter++) {
    SgInitializedName* name = *name_iter;
    SgSymbol* symbol = name->get_symbol_from_symbol_table();
    SgType *type = symbol->get_type();
    int nr_stars = 0;
    stringstream ss1;
    
    while (isSgArrayType(type) ||
            isSgPointerType(type)) {
        if (isSgArrayType(type)) {
            SgArrayType *atype = isSgArrayType(type);
            SgExpression *expr = atype->get_index();

            type = atype->get_base_type();
            ss1 << "[";
            if (expr)
                examineExpr(expr, ss1);
            ss1 << "]";
        } else {
            SgPointerType *ttype = isSgPointerType(type);
            type = ttype->get_base_type();
            nr_stars++;
        }
    }

    examinePrimTypeName(type, ret->code);
    ret->code << " ";
    for (int i = 0; i < nr_stars; ++i)
        ret->code << "*";
    ret->code << symbol->get_name().getString();
    ret->code << ss1.str();

    ss1.str("");

    SgInitializer *initer = name->get_initializer();
    if (initer) {
        switch (initer->variantT()) {
            case V_SgAssignInitializer:
                SgAssignInitializer *ai = isSgAssignInitializer(initer);
                SgExpression *expr = ai->get_operand();
                if (expr) {
                    ret->code << "=";
                    gc = examineExpr(expr, ret->code);
                    if (gc != NULL)
                        delete gc;
                }
                break;
            default:
                break;
        }
    }

    /* end of this decl */
    ret->code << ";";
    out << ret->code.str();

    return ret;

    /*
    cout << "[Decl] Variable (name:"<<symbol->get_name().getString();
    cout << ",type:"<<symbol->get_type()->class_name();
    cout << ",init:";

    SgInitializer* init_expr = name->get_initializer();
    if (init_expr) 
      cout << init_expr->class_name();
    else
      cout << "none";
    cout << ")" << endl;
    */
  }
}
Beispiel #8
0
std::string initializeVariable(SgInitializedName* initName) {
	//if array type we need to get the index expression
	std::string index_expression_string;
	std::stringstream nameStringStream;
	SgName initNameName = initName->get_qualified_name();
	SgSymbol* initNameSym = initName->search_for_symbol_from_symbol_table();
	if (variablesOfNameX.find(initNameName.getString()) == variablesOfNameX.end()) {
		nameStringStream << initNameName.getString() << "_0";
		variablesOfNameX[initNameName.getString()] = 1;
	}
	else {
		int occurrence = variablesOfNameX[initNameName.getString()];
		nameStringStream << initNameName.getString() << "_" << occurrence;
		variablesOfNameX[initNameName.getString()] = occurrence+1;
	}
	SymbolToZ3[initNameSym] = nameStringStream.str();
	SymbolToInstances[initNameSym] = 0;
	SgType* initNameType = initName->get_type();
	std::string typeZ3;
	if (initNameType->isIntegerType()) {
		typeZ3 = "Int";
	}
	else if (initNameType->isFloatType()) {
		typeZ3 = "Real";
	}
	else if (isSgArrayType(initNameType)) {
		SgArrayType* arrTyp = isSgArrayType(initNameType);
		ROSE_ASSERT(arrTyp != NULL);
		SgType* underlying_type = arrTyp->get_base_type();
		std::string array_typeZ3;
		if (underlying_type->isIntegerType()) {
			array_typeZ3 = "Int";
		}
		else if (underlying_type->isFloatType()) {
			array_typeZ3 = "Real";
		}
		else {
			std::cout << "unknown underlying type of array!" << std::endl;
			std::cout << underlying_type->class_name() << std::endl;
			ROSE_ASSERT(false);
		}
		SgExpression* ind = arrTyp->get_index();
		std::stringstream arrStr;
		index_expression_string = getSgExpressionString(ind);
		typeZ3 = "(Array Int " + array_typeZ3 + ")";
	}
	else if (isSgClassType(initNameType)) {
		
		std::cout << "structs are not yet implemented" << std::endl;
		ROSE_ASSERT(false);
	}
	else if (isSgPointerType(initNameType)) {
		std::cout << "pointers are not yet implemented" << std::endl;
		ROSE_ASSERT(false);
	}
	else if (isSgEnumType(initNameType)) {
		SgEnumType* et = isSgEnumType(initNameType);
		SgEnumDeclaration* enum_d = isSgEnumDeclaration(et->getAssociatedDeclaration());
		getSgDeclarationStatement(enum_d);	
		typeZ3 = et->get_name().getString(); 
	}
	else {
		std::cout << "unknown type: " << initNameType->class_name() << std::endl;
		ROSE_ASSERT(false);
	}		
	std::string name = nameStringStream.str() + "_0";
	std::stringstream streamZ3;
	if (isSgArrayType(initNameType)) {
	streamZ3 << "(declare-const " << name << " " << typeZ3 << ")";
	streamZ3 << "\n(declare-fun " << name << "_len () Int)";
	streamZ3 << "\n(assert (= " << name << "_len " << index_expression_string << "))"; 	
	#ifdef ARRAY_TEST
	std::cout << "arrStream: " << streamZ3.str() << std::endl;
	#endif

	}
	else if (isSgEnumType(initNameType)) {
		streamZ3 << "(declare-const " << name << " " << typeZ3 << ")";
	}
	else {
	streamZ3 << "(declare-fun " << name << " () " << typeZ3 << ")";
	}
	return streamZ3.str();
}
int
main( int argc, char* argv[] )
   {
  // Initialize and check compatibility. See rose::initialize
     ROSE_INITIALIZE;

     SgProject* project = frontend(argc,argv);
     AstTests::runAllTests(project);

#if 0
  // Output the graph so that we can see the whole AST graph, for debugging.
     generateAstGraph(project, 4000);
#endif
#if 1
     printf ("Generate the dot output of the SAGE III AST \n");
     generateDOT ( *project );
     printf ("DONE: Generate the dot output of the SAGE III AST \n");
#endif

  // There are lots of way to write this, this is one simple approach; get all the function calls.
     std::vector<SgNode*> functionCalls = NodeQuery::querySubTree (project,V_SgFunctionCallExp);

  // Find the SgFunctionSymbol for snprintf so that we can reset references to "sprintf" to "snprintf" instead.
  // SgGlobal* globalScope = (*project)[0]->get_globalScope();
     SgSourceFile* sourceFile = isSgSourceFile(project->get_fileList()[0]);
     ROSE_ASSERT(sourceFile != NULL);
     SgGlobal* globalScope = sourceFile->get_globalScope();
     SgFunctionSymbol* snprintf_functionSymbol = globalScope->lookup_function_symbol("snprintf");
     ROSE_ASSERT(snprintf_functionSymbol != NULL);

  // Iterate over the function calls to find the calls to "sprintf"
     for (unsigned long i = 0; i < functionCalls.size(); i++)
        {
          SgFunctionCallExp* functionCallExp = isSgFunctionCallExp(functionCalls[i]);
          ROSE_ASSERT(functionCallExp != NULL);

          SgFunctionRefExp* functionRefExp = isSgFunctionRefExp(functionCallExp->get_function());
          if (functionRefExp != NULL)
             {
               SgFunctionSymbol* functionSymbol = functionRefExp->get_symbol();
               if (functionSymbol != NULL)
                  {
                    SgName functionName = functionSymbol->get_name();
                 // printf ("Function being called: %s \n",functionName.str());
                    if (functionName == "sprintf")
                       {
                      // Now we have something to do!
                         functionRefExp->set_symbol(snprintf_functionSymbol);

                      // Now add the "n" argument
                         SgExprListExp* functionArguments = functionCallExp->get_args();
                         SgExpressionPtrList & functionArgumentList = functionArguments->get_expressions();

                      // "sprintf" shuld have exactly 2 arguments (I guess the "..." don't count)
                         printf ("functionArgumentList.size() = %zu \n",functionArgumentList.size());
                      // ROSE_ASSERT(functionArgumentList.size() == 2);
                         SgExpressionPtrList::iterator i = functionArgumentList.begin();

                      // printf ("(*i) = %p = %s = %s \n",*i,(*i)->class_name().c_str(),SageInterface::get_name(*i).c_str());
                         SgVarRefExp* variableRefExp = isSgVarRefExp(*i);
                         ROSE_ASSERT(variableRefExp != NULL);

                      // printf ("variableRefExp->get_type() = %p = %s = %s \n",variableRefExp->get_type(),variableRefExp->get_type()->class_name().c_str(),SageInterface::get_name(variableRefExp->get_type()).c_str());

                         SgType* bufferType = variableRefExp->get_type();
                         SgExpression* bufferLengthExpression = NULL;
                         switch(bufferType->variantT())
                            {
                              case V_SgArrayType:
                                 {
                                   SgArrayType* arrayType = isSgArrayType(bufferType);
                                   bufferLengthExpression = arrayType->get_index();
                                   break;
                                 }

                              case V_SgPointerType:
                                 {
                                // SgPointerType* pointerType = isSgPointerType(bufferType);
                                   SgInitializedName* variableDeclaration = variableRefExp->get_symbol()->get_declaration();
                                   ROSE_ASSERT(variableDeclaration != NULL);
                                   SgExpression* initializer = variableDeclaration->get_initializer();
                                   if (initializer != NULL)
                                      {
                                        SgAssignInitializer* assignmentInitializer = isSgAssignInitializer(initializer);
                                        ROSE_ASSERT(assignmentInitializer != NULL);

                                     // This is the rhs of the initialization of the pointer (likely a malloc through a cast).
                                     // This assumes: buffer = (char*) malloc(bufferLengthExpression);
                                        SgExpression* initializationExpression = assignmentInitializer->get_operand();
                                        ROSE_ASSERT(initializationExpression != NULL);
                                        SgCastExp* castExp = isSgCastExp(initializationExpression);
                                        ROSE_ASSERT(castExp != NULL);
                                        SgFunctionCallExp* functionCall = isSgFunctionCallExp(castExp->get_operand());
                                        ROSE_ASSERT(functionCall != NULL);
                                        SgExprListExp* functionArguments = isSgExprListExp(functionCall->get_args());
                                        bufferLengthExpression = functionArguments->get_expressions()[0];
                                        ROSE_ASSERT(bufferLengthExpression != NULL);
                                      }
                                     else
                                      {
                                        printf ("Initializer not found, so no value for n in snprintf can be computed currently \n");
                                      }
                                   break;
                                 }

                              default:
                                 {
                                   printf ("Error: default reached in evaluation of buffer type = %p = %s \n",bufferType,bufferType->class_name().c_str());
                                   ROSE_ASSERT(false);
                                 }
                            }

                         ROSE_ASSERT(bufferLengthExpression != NULL);

                      // printf ("bufferLengthExpression = %p = %s = %s \n",bufferLengthExpression,bufferLengthExpression->class_name().c_str(),SageInterface::get_name(bufferLengthExpression).c_str());

                      // Jump over the first argument, the "n" is defined to be the 2nd argument (the rest are shifted one position).
                         i++;

                      // Build a deep copy of the expression used to define the static buffer (could be any complex expression).
                         SgTreeCopy copy_help;
                         SgExpression* bufferLengthExpression_copy = isSgExpression(bufferLengthExpression->copy(copy_help));

                      // Insert the "n" for the parameter list to work with "snprintf" instead of "sprintf"
                         functionArgumentList.insert(i,bufferLengthExpression_copy);
                       }
                  }
             }
        }

     return backend(project);
   }