private static bool RemoveReturnCheck(Statement stat, StructMethod mt) { Statement parent = stat.GetParent(); if (parent != null && parent.type == Statement.Type_If && stat.type == Statement. Type_Basicblock && stat.GetExprents().Count == 1) { Exprent exprent = stat.GetExprents()[0]; if (exprent.type == Exprent.Exprent_Exit) { ExitExprent exit_exprent = (ExitExprent)exprent; if (exit_exprent.GetExitType() == ExitExprent.Exit_Return) { Exprent exprent_value = exit_exprent.GetValue(); //if(exprent_value.type == Exprent.EXPRENT_VAR) { // VarExprent var_value = (VarExprent)exprent_value; IfStatement ifparent = (IfStatement)parent; Exprent if_condition = ifparent.GetHeadexprent().GetCondition(); if (ifparent.GetElsestat() == stat && if_condition.type == Exprent.Exprent_Function && ((FunctionExprent)if_condition).GetFuncType() == FunctionExprent.Function_Eq) { // TODO: reversed order possible (in theory) FunctionExprent func = (FunctionExprent)if_condition; Exprent first_param = func.GetLstOperands()[0]; Exprent second_param = func.GetLstOperands()[1]; StatEdge ifedge = ifparent.GetIfEdge(); StatEdge elseedge = ifparent.GetElseEdge(); Statement ifbranch = ifparent.GetIfstat(); Statement elsebranch = ifparent.GetElsestat(); if (second_param.type == Exprent.Exprent_Const && second_param.GetExprType().type == ICodeConstants.Type_Null) { // TODO: reversed parameter order //if(first_param.type == Exprent.EXPRENT_VAR && ((VarExprent)first_param).getIndex() == var_value.getIndex()) { if (first_param.Equals(exprent_value)) { // TODO: check for absence of side effects like method invocations etc. if (ifbranch.type == Statement.Type_Basicblock && ifbranch.GetExprents().Count == 1 && ifbranch.GetExprents()[0].type == Exprent.Exprent_Exit) { // TODO: special check for IllegalStateException ifparent.GetFirst().RemoveSuccessor(ifedge); ifparent.GetFirst().RemoveSuccessor(elseedge); ifparent.GetStats().RemoveWithKey(ifbranch.id); ifparent.GetStats().RemoveWithKey(elsebranch.id); if (!(ifbranch.GetAllSuccessorEdges().Count == 0)) { ifbranch.RemoveSuccessor(ifbranch.GetAllSuccessorEdges()[0]); } if (!(ifparent.GetFirst().GetExprents().Count == 0)) { elsebranch.GetExprents().InsertRange(0, ifparent.GetFirst().GetExprents()); } ifparent.GetParent().ReplaceStatement(ifparent, elsebranch); ifparent.GetParent().SetAllParent(); return(true); } } } } } } } else if (parent != null && parent.type == Statement.Type_Sequence && stat.type == Statement.Type_Basicblock && stat.GetExprents().Count == 1) { //} Exprent exprent = stat.GetExprents()[0]; if (exprent.type == Exprent.Exprent_Exit) { ExitExprent exit_exprent = (ExitExprent)exprent; if (exit_exprent.GetExitType() == ExitExprent.Exit_Return) { Exprent exprent_value = exit_exprent.GetValue(); SequenceStatement sequence = (SequenceStatement)parent; int sequence_stats_number = sequence.GetStats().Count; if (sequence_stats_number > 1 && sequence.GetStats().GetLast() == stat && sequence .GetStats()[sequence_stats_number - 2].type == Statement.Type_If) { IfStatement ifstat = (IfStatement)sequence.GetStats()[sequence_stats_number - 2]; Exprent if_condition = ifstat.GetHeadexprent().GetCondition(); if (ifstat.iftype == IfStatement.Iftype_If && if_condition.type == Exprent.Exprent_Function && ((FunctionExprent)if_condition).GetFuncType() == FunctionExprent.Function_Eq) { // TODO: reversed order possible (in theory) FunctionExprent func = (FunctionExprent)if_condition; Exprent first_param = func.GetLstOperands()[0]; Exprent second_param = func.GetLstOperands()[1]; Statement ifbranch = ifstat.GetIfstat(); if (second_param.type == Exprent.Exprent_Const && second_param.GetExprType().type == ICodeConstants.Type_Null) { // TODO: reversed parameter order if (first_param.Equals(exprent_value)) { // TODO: check for absence of side effects like method invocations etc. if (ifbranch.type == Statement.Type_Basicblock && ifbranch.GetExprents().Count == 1 && ifbranch.GetExprents()[0].type == Exprent.Exprent_Exit) { // TODO: special check for IllegalStateException ifstat.RemoveSuccessor(ifstat.GetAllSuccessorEdges()[0]); // remove 'else' edge if (!(ifstat.GetFirst().GetExprents().Count == 0)) { stat.GetExprents().InsertRange(0, ifstat.GetFirst().GetExprents()); } foreach (StatEdge edge in ifstat.GetAllPredecessorEdges()) { ifstat.RemovePredecessor(edge); edge.GetSource().ChangeEdgeNode(Statement.Direction_Forward, edge, stat); stat.AddPredecessor(edge); } sequence.GetStats().RemoveWithKey(ifstat.id); sequence.SetFirst(sequence.GetStats()[0]); return(true); } } } } } } } } foreach (Statement st in stat.GetStats()) { if (RemoveReturnCheck(st, mt)) { return(true); } } return(false); }
private static void RemoveEmptyStatements(SequenceStatement sequence) { if (sequence.GetStats().Count <= 1) { return; } MergeFlatStatements(sequence); while (true) { bool found = false; foreach (Statement st in sequence.GetStats()) { if (st.GetExprents() != null && (st.GetExprents().Count == 0)) { if ((st.GetAllSuccessorEdges().Count == 0)) { List <StatEdge> lstBreaks = st.GetPredecessorEdges(StatEdge.Type_Break); if ((lstBreaks.Count == 0)) { foreach (StatEdge edge in st.GetAllPredecessorEdges()) { edge.GetSource().RemoveSuccessor(edge); } found = true; } } else { StatEdge sucedge = st.GetAllSuccessorEdges()[0]; if (sucedge.GetType() != StatEdge.Type_Finallyexit) { st.RemoveSuccessor(sucedge); foreach (StatEdge edge in st.GetAllPredecessorEdges()) { if (sucedge.GetType() != StatEdge.Type_Regular) { edge.GetSource().ChangeEdgeType(Statement.Direction_Forward, edge, sucedge.GetType ()); } st.RemovePredecessor(edge); edge.GetSource().ChangeEdgeNode(Statement.Direction_Forward, edge, sucedge.GetDestination ()); sucedge.GetDestination().AddPredecessor(edge); if (sucedge.closure != null) { sucedge.closure.AddLabeledEdge(edge); } } found = true; } } if (found) { sequence.GetStats().RemoveWithKey(st.id); break; } } } if (!found) { break; } } sequence.SetFirst(sequence.GetStats()[0]); }