Beispiel #1
0
        private void GenStmt(ParseTreeNode stmt, ILGenerator il, SymbolTable symbolTable)
        {
            if (stmt.Term.Name == "program")
            {
                if (stmt.ChildNodes.Count > 0)
                {
                    this.GenStmt(stmt.ChildNodes[0].ChildNodes[0], il, symbolTable);
                    this.GenStmt(stmt.ChildNodes[1], il, symbolTable);
                }
            }
            else if (stmt.Term.Name == "variableDeclaration")
            {
                Type localType;
                // declare a local
                if (stmt.ChildNodes[2].Term.Name == "typeSpecifier")
                {
                    localType = this.TypeOfTypeDeclaration(stmt.ChildNodes[2].ChildNodes[1]);
                }
                else
                {
                    localType = this.TypeOfExpr(stmt.ChildNodes[2].ChildNodes[1], symbolTable);
                    //symbolTable.locals[stmt.ChildNodes[1].ChildNodes[0].Token.ValueString] = il.DeclareLocal(this.TypeOfExpr(stmt.ChildNodes[2].ChildNodes[1], symbolTable));
                }
                Action <string> generateAssign = null;
                ParseTreeNode   assign         = stmt.ChildNodes.Where(x => x.Term.Name == "setEqual").SingleOrDefault();
                // set the initial value
                if (assign != null)
                {
                    generateAssign = new Action <string>(name =>
                    {
                        this.GenExpr(assign.ChildNodes[1], symbolTable.locals[name].LocalType, il, symbolTable);
                        symbolTable.Store(name, this.TypeOfExpr(assign.ChildNodes[1], symbolTable), il);
                    });
                }
                var variableIden = stmt.ChildNodes[1];
                while (true)
                {
                    string name = variableIden.ChildNodes[0].Token.ValueString;
                    symbolTable.AddLocal(name, il.DeclareLocal(localType));
                    if (generateAssign != null)
                    {
                        generateAssign(name);
                    }

                    if (variableIden.ChildNodes.Count < 2)
                    {
                        break;
                    }
                    variableIden = variableIden.ChildNodes[1];
                }
            }
            else if (stmt.Term.Name == "io")
            {
                if (stmt.ChildNodes[0].Token.ValueString == "put")
                {
                    ParseTreeNode argItem = stmt.ChildNodes[1];
                    while (true)
                    {
                        this.GenExpr(argItem.ChildNodes[0], typeof(string), il, symbolTable);
                        il.Emit(OpCodes.Call, typeof(System.Console).GetMethod("Write", new System.Type[] { typeof(string) }));
                        if (argItem.ChildNodes.Count > 1)
                        {
                            argItem = argItem.ChildNodes[1];
                        }
                        else
                        {
                            break;
                        }
                    }
                    il.Emit(OpCodes.Call, typeof(System.Console).GetMethod("WriteLine", new System.Type[] { }));
                }
            }
            else if (stmt.Term.Name == "assignment")
            {
                string ident = stmt.ChildNodes[0].Token.ValueString;
                this.GenExpr(stmt.ChildNodes[1].ChildNodes[1], this.TypeOfExpr(stmt.ChildNodes[1].ChildNodes[1], symbolTable), il, symbolTable);
                symbolTable.Store(ident, this.TypeOfExpr(stmt.ChildNodes[1].ChildNodes[1], symbolTable), il);
                //this.Store(ident, this.TypeOfExpr(stmt.ChildNodes[1].ChildNodes[1], symbolTable), ref il, symbolTable);
            }
            else if (stmt.Term.Name == "functionDefinition")
            {
                string functionName = stmt.ChildNodes[1].Token.ValueString;
                if (functionTable.ContainsKey(functionName))
                {
                    throw new Exception(functionName + " has already been defined");
                }
                var         parameterList = new List <FunctionDefinition.Argument>();
                List <Type> types         = new List <Type>();
                SymbolTable localSymbols  = new SymbolTable();
                if (stmt.ChildNodes[2].ChildNodes.Count > 0)
                {
                    var currParam = stmt.ChildNodes[2].ChildNodes[0];
                    while (true)
                    {
                        var parameterType   = TypeOfExpr(currParam.ChildNodes[0].ChildNodes[1].ChildNodes[1], symbolTable);
                        var paramIdentifier = currParam.ChildNodes[0].ChildNodes[0];
                        while (true)
                        {
                            var parameterName = paramIdentifier.ChildNodes[0].Token.ValueString;
                            parameterList.Add(new FunctionDefinition.Argument()
                            {
                                argName = parameterName, argType = parameterType
                            });
                            localSymbols.AddParameter(parameterName, parameterType);
                            types.Add(parameterType);
                            if (paramIdentifier.ChildNodes.Count == 1)
                            {
                                break;
                            }
                            paramIdentifier = paramIdentifier.ChildNodes[1];
                        }

                        if (currParam.ChildNodes.Count == 1)
                        {
                            break;
                        }
                        currParam = currParam.ChildNodes[1];
                    }
                }
                var methodDeclaration = mainProgram.DefineMethod(functionName, MethodAttributes.Static, TypeOfExpr(stmt.ChildNodes[3].ChildNodes[1], symbolTable), types.ToArray());
                var ilMeth            = methodDeclaration.GetILGenerator();
                //if (stmt.ChildNodes[2].ChildNodes.Count > 0)
                //{
                //    var currParam = stmt.ChildNodes[2].ChildNodes[0];
                //    while (true)
                //    {
                //        //localSymbols.parameters.Add(new Tuple<string, Type>(currParam.ChildNodes[0].ChildNodes[0].Token.ValueString, TypeOfExpr(currParam.ChildNodes[0].ChildNodes[1].ChildNodes[1], symbolTable)));
                //        if (currParam.ChildNodes.Count == 1)
                //            break;
                //        currParam = currParam.ChildNodes[1];
                //    }
                //}
                GenStmt(stmt.ChildNodes[4], ilMeth, localSymbols);
                ilMeth.Emit(OpCodes.Ret);
                var methodDec = new FunctionDefinition()
                {
                    methodDefinition = methodDeclaration,
                    arguments        = parameterList
                };
                functionTable.Add(functionName, methodDec);
            }
            else if (stmt.Term.Name == "result")
            {
                GenExpr(stmt.ChildNodes[1], TypeOfExpr(stmt.ChildNodes[1], symbolTable), il, symbolTable);
                var result = il.DeclareLocal(TypeOfExpr(stmt.ChildNodes[1], symbolTable));
                il.Emit(OpCodes.Stloc, result);
                il.Emit(OpCodes.Ldloc, result);
                il.Emit(OpCodes.Ret, result);
            }

            /*
             * else if (stmt is ReadInt)
             * {
             *  this.il.Emit(Emit.OpCodes.Call, typeof(System.Console).GetMethod("ReadLine", System.Reflection.BindingFlags.Public | System.Reflection.BindingFlags.Static, null, new System.Type[] { }, null));
             *  this.il.Emit(Emit.OpCodes.Call, typeof(int).GetMethod("Parse", System.Reflection.BindingFlags.Public | System.Reflection.BindingFlags.Static, null, new System.Type[] { typeof(string) }, null));
             *  this.Store(((ReadInt)stmt).Ident, typeof(int));
             * }
             * else if (stmt is ForLoop)
             * {
             *  // example:
             *  // for x = 0 to 100 do
             *  //   print "hello";
             *  // end;
             *
             *  // x = 0
             *  ForLoop forLoop = (ForLoop)stmt;
             *  Assign assign = new Assign();
             *  assign.Ident = forLoop.Ident;
             *  assign.Expr = forLoop.From;
             *  this.GenStmt(assign);
             *  // jump to the test
             *  Emit.Label test = this.il.DefineLabel();
             *  this.il.Emit(Emit.OpCodes.Br, test);
             *
             *  // statements in the body of the for loop
             *  Emit.Label body = this.il.DefineLabel();
             *  this.il.MarkLabel(body);
             *  this.GenStmt(forLoop.Body);
             *
             *  // to (increment the value of x)
             *  this.il.Emit(Emit.OpCodes.Ldloc, this.symbolTable[forLoop.Ident]);
             *  this.il.Emit(Emit.OpCodes.Ldc_I4, 1);
             *  this.il.Emit(Emit.OpCodes.Add);
             *  this.Store(forLoop.Ident, typeof(int));
             *
             *  // **test** does x equal 100? (do the test)
             *  this.il.MarkLabel(test);
             *  this.il.Emit(Emit.OpCodes.Ldloc, this.symbolTable[forLoop.Ident]);
             *  this.GenExpr(forLoop.To, typeof(int));
             *  this.il.Emit(Emit.OpCodes.Blt, body);
             * }*/
            else
            {
                throw new System.Exception("don't know how to gen a " + stmt.Term.Name);
            }
        }
Beispiel #2
0
        private void GenStmt(ParseTreeNode stmt, ILGenerator il, SymbolTable symbolTable, Label?exitScope = null)
        {
            if (stmt.Term.Name == "program")
            {
                if (stmt.ChildNodes.Count > 0)
                {
                    this.GenStmt(stmt.ChildNodes[0].ChildNodes[0], il, symbolTable);
                    this.GenStmt(stmt.ChildNodes[1], il, symbolTable);
                }
            }
            else if (stmt.Term.Name == "variableDeclaration")
            {
                Type localType;
                // declare a local
                if (stmt.ChildNodes[2].Term.Name == "typeSpecifier")
                {
                    localType = this.TypeOfTypeDeclaration(stmt.ChildNodes[2].ChildNodes[0]);
                }
                else
                {
                    localType = TypeOfExpr(stmt.ChildNodes[2].ChildNodes[1], symbolTable);
                }
                Action <string> generateAssign = null;
                ParseTreeNode   assign         = stmt.ChildNodes.Where(x => x.Term.Name == "setEqual").SingleOrDefault();
                // set the initial value
                if (assign != null)
                {
                    generateAssign = new Action <string>(name =>
                    {
                        this.GenExpr(assign.ChildNodes[1], symbolTable.locals[name].LocalType, il, symbolTable);
                        symbolTable.Store(name, TypeOfExpr(assign.ChildNodes[1], symbolTable), il);
                    });
                }
                var variableIden = stmt.ChildNodes[1];
                while (true)
                {
                    string name = variableIden.ChildNodes[0].Token.ValueString;
                    symbolTable.AddLocal(name, il.DeclareLocal(localType));
                    if (generateAssign != null)
                    {
                        generateAssign(name);
                    }

                    if (variableIden.ChildNodes.Count < 2)
                    {
                        break;
                    }
                    variableIden = variableIden.ChildNodes[1];
                }
            }
            else if (stmt.Term.Name == "io")
            {
                if (stmt.ChildNodes[0].Token.ValueString == "put")
                {
                    //the first argument is always there, until we can build a proper AST this'll have to do
                    ParseTreeNode argItem = stmt.ChildNodes[1];
                    this.GenExpr(argItem.ChildNodes[0], typeof(string), il, symbolTable);
                    il.Emit(OpCodes.Call, typeof(System.Console).GetMethod("Write", new System.Type[] { typeof(string) }));
                    argItem = stmt.ChildNodes[2];
                    while (true)
                    {
                        if (argItem.ChildNodes.Count == 0)
                        {
                            break;
                        }
                        this.GenExpr(argItem.ChildNodes[0].ChildNodes[0], typeof(string), il, symbolTable);
                        il.Emit(OpCodes.Call, typeof(System.Console).GetMethod("Write", new System.Type[] { typeof(string) }));
                        argItem = argItem.ChildNodes[1];
                    }
                    if (stmt.ChildNodes[3].ChildNodes.Count == 0)//put a newline character if there is no ...
                    {
                        il.Emit(OpCodes.Call, typeof(System.Console).GetMethod("WriteLine", new System.Type[] { }));
                    }
                }
                else if (stmt.ChildNodes[0].Token.ValueString == "get")
                {
                    foreach (var argument in stmt.ChildNodes[1].ChildNodes)
                    {
                        //switch(symbolTable.TypeOfVar(
                        il.Emit(OpCodes.Call, typeof(System.Console).GetMethod("ReadLine", new System.Type[] { }));
                        symbolTable.Store(argument.Token.ValueString, typeof(string), il);
                    }
                }
            }
            else if (stmt.Term.Name == "assignment")
            {
                if (stmt.ChildNodes[0].Term.Name == "functionCall")//if we see this as a function call, we know that's not true, and it's actually an array (which is kinda the same thing in turing)
                {
                    string arrayName = stmt.ChildNodes[0].ChildNodes[0].Token.ValueString;
                    if (symbolTable.TypeOfVar(arrayName).IsArray)
                    {
                        symbolTable.PushVar(arrayName, il);
                        if (stmt.ChildNodes[0].ChildNodes[1].ChildNodes.Count > 1)
                        {
                            throw new NotImplementedException("Multi-Dimensional arrays are not yet supported");
                        }

                        this.GenExpr(stmt.ChildNodes[0].ChildNodes[1].ChildNodes[0], typeof(int), il, symbolTable);
                        this.GenExpr(stmt.ChildNodes[1].ChildNodes[1], TypeOfExpr(stmt.ChildNodes[1].ChildNodes[1], symbolTable), il, symbolTable);

                        il.Emit(OpCodes.Stelem, symbolTable.TypeOfVar(arrayName).GetElementType());
                    }
                    else
                    {
                        throw new NotSupportedException(String.Format("Non-array identifier used like an array: {0}", arrayName));
                    }
                }
                else
                {
                    this.GenExpr(stmt.ChildNodes[1].ChildNodes[1], TypeOfExpr(stmt.ChildNodes[1].ChildNodes[1], symbolTable), il, symbolTable);
                    string ident = stmt.ChildNodes[0].Token.ValueString;
                    symbolTable.Store(ident, TypeOfExpr(stmt.ChildNodes[1].ChildNodes[1], symbolTable), il);
                }
            }
            else if (stmt.Term.Name == "functionDefinition")
            {
                string functionName = stmt.ChildNodes[0].ChildNodes[1].Token.ValueString;

                SymbolTable localSymbols = new SymbolTable(symbolTable);
                foreach (var parameter in symbolTable.functionTable[functionName].arguments)
                {
                    localSymbols.AddParameter(parameter.argName, parameter.argType);
                }

                var ilMeth = symbolTable.functionTable[functionName].GetILGenerator();
                GenStmt(stmt.ChildNodes[1], ilMeth, localSymbols);
                ilMeth.Emit(OpCodes.Ret);
            }
            else if (stmt.Term.Name == "result")
            {
                GenExpr(stmt.ChildNodes[1], TypeOfExpr(stmt.ChildNodes[1], symbolTable), il, symbolTable);
                var result = il.DeclareLocal(TypeOfExpr(stmt.ChildNodes[1], symbolTable));
                il.Emit(OpCodes.Stloc, result);
                il.Emit(OpCodes.Ldloc, result);
                il.Emit(OpCodes.Ret, result);
            }
            else if (stmt.Term.Name == "functionCall" | stmt.Term.Name == "memberCall")
            {
                GenExpr(stmt, null, il, symbolTable);
            }
            else if (stmt.Term.Name == "ifBlock")
            {
                Label ifTrue   = il.DefineLabel();
                Label ifFalse  = il.DefineLabel();
                Label endLabel = il.DefineLabel();

                GenExpr(stmt.ChildNodes[0], typeof(bool), il, symbolTable); //expression to check if true
                il.Emit(OpCodes.Brtrue, ifTrue);                            //if true then jump to true block
                il.Emit(OpCodes.Br, ifFalse);                               //otherwise jump to false block

                il.MarkLabel(ifTrue);                                       //true block
                GenStmt(stmt.ChildNodes[1], il, symbolTable);
                il.Emit(OpCodes.Br, endLabel);                              //jump to after false block

                il.MarkLabel(ifFalse);                                      //false block
                if (stmt.ChildNodes[2].ChildNodes.Count > 0)                //then there's an else-if, this takes place in the else section
                {
                    ParseTreeNode elseBlockStmt = stmt.ChildNodes[2];       //Turn the elsif to an inner if statement
                    elseBlockStmt.ChildNodes.Add(stmt.ChildNodes[3]);       //Move the optional else statement to the inner if statement
                    elseBlockStmt.Term.Name = "ifBlock";

                    GenStmt(elseBlockStmt, il, symbolTable);
                }
                else if (stmt.ChildNodes[3].ChildNodes.Count > 0)
                {
                    GenStmt(stmt.ChildNodes[3].ChildNodes[0], il, symbolTable); //generate expresson for false section, otherwise the label will be at the same spot as the end
                }
                il.MarkLabel(endLabel);                                         //the end of the if statement
            }
            else if (stmt.Term.Name == "loop")
            {
                Label beginLoop = il.DefineLabel();
                Label endLoop   = il.DefineLabel();
                il.MarkLabel(beginLoop);
                GenStmt(stmt.ChildNodes[0], il, symbolTable, endLoop);
                il.Emit(OpCodes.Br, beginLoop);
                il.MarkLabel(endLoop);
            }
            else if (stmt.Term.Name == "forLoop")
            {
                il.BeginScope();

                Label        beginLoop = il.DefineLabel();
                Label        endLoop   = il.DefineLabel();
                LocalBuilder i         = il.DeclareLocal(typeof(int));
                string       identName = stmt.ChildNodes[1].Token.ValueString;
                symbolTable.AddLocal(identName, i);
                symbolTable.AddLocal("___endLoop", il.DeclareLocal(typeof(int)));
                if (stmt.ChildNodes[2].ChildNodes.Count == 1)//then an identifier is used as a range, or char. We just fail for now
                {
                    throw new NotImplementedException();
                }
                else
                {
                    GenExpr(stmt.ChildNodes[2].ChildNodes[0], typeof(int), il, symbolTable);
                    symbolTable.Store(identName, typeof(int), il);
                    GenExpr(stmt.ChildNodes[2].ChildNodes[1], typeof(int), il, symbolTable);
                    symbolTable.Store("___endLoop", typeof(int), il);
                }
                il.MarkLabel(beginLoop);
                GenStmt(stmt.ChildNodes[4], il, symbolTable, endLoop);
                symbolTable.PushVar(identName, il);
                il.Emit(OpCodes.Ldc_I4_1);
                if (stmt.ChildNodes[3].ChildNodes.Count > 0)//then there is a decreasing statement, so do decreasing
                {
                    il.Emit(OpCodes.Sub);
                }
                else
                {
                    il.Emit(OpCodes.Add);
                }
                il.Emit(OpCodes.Dup);
                symbolTable.Store(identName, typeof(int), il);
                symbolTable.PushVar("___endLoop", il);

                if (stmt.ChildNodes[3].ChildNodes.Count > 0)//then there is a decreasing statement, so do decreasing
                {
                    il.Emit(OpCodes.Bge, beginLoop);
                }
                else
                {
                    il.Emit(OpCodes.Ble, beginLoop);
                }
                il.MarkLabel(endLoop);
                symbolTable.RemoveLocal(identName);
                symbolTable.RemoveLocal("___endLoop");

                il.EndScope();
            }
            else
            {
                throw new System.Exception("don't know how to gen a " + stmt.Term.Name);
            }
        }