コード例 #1
0
 public static void ValidatePayloadTypes(ITranslationErrorHandler handler, ParserRuleContext context,
                                         PLanguageType payloadType, IReadOnlyList <IPExpr> arguments)
 {
     if (arguments.Count == 0)
     {
         if (!payloadType.IsSameTypeAs(PrimitiveType.Null))
         {
             throw handler.TypeMismatch(context, PrimitiveType.Null, payloadType);
         }
     }
     else if (arguments.Count == 1)
     {
         CheckArgument(handler, context, payloadType, arguments[0]);
     }
     else if (payloadType.Canonicalize() is TupleType tuple)
     {
         foreach (Tuple <IPExpr, PLanguageType> pair in arguments.Zip(tuple.Types, Tuple.Create))
         {
             CheckArgument(handler, context, pair.Item2, pair.Item1);
         }
     }
     else
     {
         throw handler.IncorrectArgumentCount(context, arguments.Count, 1);
     }
 }
コード例 #2
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ファイル: MachineChecker.cs プロジェクト: yzhang90/P-1
        private static State FindStartState(Machine machine, ITranslationErrorHandler handler)
        {
            bool foundStartState = false;

            foreach (State state in machine.AllStates())
            {
                if (state == machine.StartState || state.IsStart)
                {
                    if (!foundStartState)
                    {
                        foundStartState = true;
                    }
                    else
                    {
                        throw handler.TwoStartStates(machine, state);
                    }
                }
            }

            Debug.Assert(!(foundStartState && machine.StartState == null), "machine has unregistered start state");

            if (!foundStartState || machine.StartState == null)
            {
                throw handler.MissingStartState(machine);
            }

            return(machine.StartState);
        }
コード例 #3
0
ファイル: TypeResolver.cs プロジェクト: yzhang90/P-1
 public static PLanguageType ResolveType(
     ParserRuleContext context,
     Scope scope,
     ITranslationErrorHandler handler)
 {
     return(context == null ? PrimitiveType.Null : new TypeVisitor(scope, handler).Visit(context));
 }
コード例 #4
0
ファイル: Validator.cs プロジェクト: zhaowei19920524/P
        private static State FindStartState(Machine machine, ITranslationErrorHandler handler)
        {
            var foundStartState = false;

            foreach (State state in machine.AllStates())
            {
                if (state == machine.StartState || state.IsStart)
                {
                    if (!foundStartState)
                    {
                        foundStartState = true;
                    }
                    else
                    {
                        throw handler.InternalError(state.SourceLocation,
                                                    $"Two start states {state.Name} occurs twice in all states list");
                    }
                }
            }

            if (foundStartState && machine.StartState == null)
            {
                throw handler.InternalError(machine.SourceLocation, "machine has unregistered start state");
            }

            if (!foundStartState || machine.StartState == null)
            {
                // Allow machines with no start state so long as there are no other states.
                throw handler.MissingStartState(machine);
            }

            return(machine.StartState);
        }
コード例 #5
0
ファイル: ModuleExprVisitor.cs プロジェクト: tushetodorov/P
 public ModuleExprVisitor(
     ITranslationErrorHandler handler,
     Scope globalScope)
 {
     this.handler     = handler;
     this.globalScope = globalScope;
 }
コード例 #6
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ファイル: Scope.cs プロジェクト: zhaowei19920524/P
 public Scope(ITranslationErrorHandler handler, Scope parent)
 {
     this.handler = handler;
     parent?.children.Remove(this);
     Parent = parent;
     parent?.children.Add(this);
 }
コード例 #7
0
ファイル: ANTLRCompiler.cs プロジェクト: zhaowei19920524/P
        private static PParser.ProgramContext Parse(ITranslationErrorHandler handler, FileInfo inputFile)
        {
            var fileStream = new AntlrFileStream(inputFile.FullName);
            var lexer      = new PLexer(fileStream);
            var tokens     = new CommonTokenStream(lexer);
            var parser     = new PParser(tokens);

            parser.RemoveErrorListeners();

            try
            {
                // Stage 1: use fast SLL parsing strategy
                parser.Interpreter.PredictionMode = PredictionMode.Sll;
                parser.ErrorHandler = new BailErrorStrategy();
                return(parser.program());
            }
            catch (Exception e) when(e is RecognitionException || e is OperationCanceledException)
            {
                // Stage 2: use slower LL(*) parsing strategy
                tokens.Reset();
                parser.AddErrorListener(new PParserErrorListener(inputFile, handler));
                parser.Interpreter.PredictionMode = PredictionMode.Ll;
                parser.ErrorHandler = new DefaultErrorStrategy();
                return(parser.program());
            }
        }
コード例 #8
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ファイル: FunctionBodyVisitor.cs プロジェクト: jzhang919/P
        public static void PopulateMethod(ITranslationErrorHandler handler, Function fun)
        {
            Contract.Requires(fun.Body == null);
            var visitor = new FunctionBodyVisitor(handler, fun.Owner, fun);

            visitor.Visit(fun.SourceLocation);
        }
コード例 #9
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        private static void ValidateEventPayloadToTransitionTarget(ITranslationErrorHandler handler,
                                                                   ParserRuleContext sourceLocation,
                                                                   PLanguageType eventPayloadType,
                                                                   Function targetFunction)
        {
            IReadOnlyList <PLanguageType> entrySignature = targetFunction.Signature.ParameterTypes.ToList();

            if (entrySignature.Count == 0)
            {
                return;
            }

            if (entrySignature.Count == 1 && entrySignature[0].IsAssignableFrom(eventPayloadType))
            {
                return;
            }

            if (entrySignature.Count == 1 && eventPayloadType.Canonicalize() is TupleType tuple &&
                tuple.Types.Count == 1 && entrySignature[0].IsAssignableFrom(tuple.Types[0]))
            {
                return;
            }

            if (entrySignature.Count == 1)
            {
                throw handler.TypeMismatch(sourceLocation, eventPayloadType, entrySignature[0]);
            }

            PLanguageType entrySignatureType = new TupleType(entrySignature.ToArray());

            if (!entrySignatureType.IsAssignableFrom(eventPayloadType))
            {
                throw handler.TypeMismatch(sourceLocation, eventPayloadType, entrySignatureType);
            }
        }
コード例 #10
0
ファイル: StatementVisitor.cs プロジェクト: zhaowei19920524/P
 public StatementVisitor(ITranslationErrorHandler handler, Machine machine, Function method)
 {
     this.handler = handler;
     this.machine = machine;
     this.method  = method;
     table        = method.Scope;
     exprVisitor  = new ExprVisitor(method, handler);
 }
コード例 #11
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        public static void Validate(ITranslationErrorHandler handler, Machine machine)
        {
            var startState            = FindStartState(machine, handler);
            var startStatePayloadType = GetStatePayload(startState);

            Debug.Assert(startStatePayloadType.IsSameTypeAs(machine.PayloadType));
            ValidateTransitions(handler, machine);
        }
コード例 #12
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        public static void AnalyzeMethods(ITranslationErrorHandler handler, IEnumerable <Function> allFunctions)
        {
            ControlFlowChecker checker = new ControlFlowChecker(handler);

            foreach (Function function in allFunctions)
            {
                checker.CheckFunction(function);
            }
        }
コード例 #13
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 private DeclarationVisitor(
     ITranslationErrorHandler handler,
     Scope topLevelScope,
     ParseTreeProperty <IPDecl> nodesToDeclarations)
 {
     Handler                  = handler;
     currentScope             = new StackProperty <Scope>(topLevelScope);
     this.nodesToDeclarations = nodesToDeclarations;
 }
コード例 #14
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        public static void PopulateDeclarations(
            ITranslationErrorHandler handler,
            Scope topLevelScope,
            PParser.ProgramContext context,
            ParseTreeProperty <IPDecl> nodesToDeclarations)
        {
            var visitor = new DeclarationVisitor(handler, topLevelScope, nodesToDeclarations);

            visitor.Visit(context);
        }
コード例 #15
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        public static void AnalyzeMethods(ITranslationErrorHandler handler, IEnumerable <Function> allFunctions)
        {
            var checker = new LinearTypeChecker(handler);

            foreach (Function function in allFunctions)
            {
                checker.CheckFunction(function);
            }
            checker.CheckInterproceduralCalls();
        }
コード例 #16
0
ファイル: ModuleExprVisitor.cs プロジェクト: tushetodorov/P
        public static void PopulateAllModuleExprs(
            ITranslationErrorHandler handler,
            Scope globalScope)
        {
            var modExprVisitor = new ModuleExprVisitor(handler, globalScope);

            // first do all the named modules
            foreach (var mod in globalScope.NamedModules)
            {
                var context = (PParser.NamedModuleDeclContext)mod.SourceLocation;
                mod.ModExpr = modExprVisitor.Visit(context.modExpr());
            }

            // all the test declarations
            foreach (var test in globalScope.SafetyTests)
            {
                var context = (PParser.SafetyTestDeclContext)test.SourceLocation;
                test.ModExpr = modExprVisitor.Visit(context.modExpr());
            }

            foreach (var test in globalScope.RefinementTests)
            {
                var context = (PParser.RefinementTestDeclContext)test.SourceLocation;
                test.LeftModExpr  = modExprVisitor.Visit(context.modExpr()[0]);
                test.RightModExpr = modExprVisitor.Visit(context.modExpr()[1]);
            }

            if (globalScope.Implementations.Any())
            {
                // all user defind implementations
                foreach (var impl in globalScope.Implementations)
                {
                    var context = (PParser.ImplementationDeclContext)impl.SourceLocation;
                    impl.ModExpr = modExprVisitor.Visit(context.modExpr());
                }
            }
            else if (!globalScope.SafetyTests.Any())
            {
                var defaultImplDecl = new Implementation(ParserRuleContext.EmptyContext, "DefaultImpl")
                {
                    Main = "Main"
                };
                // create bindings from each machine to itself
                var defaultBindings = new List <Tuple <Interface, Machine> >();
                foreach (var machine in globalScope.Machines.Where(m => !m.IsSpec))
                {
                    globalScope.Get(machine.Name, out Interface @interface);
                    defaultBindings.Add(new Tuple <Interface, Machine>(@interface, machine));
                }

                defaultImplDecl.ModExpr = new BindModuleExpr(ParserRuleContext.EmptyContext, defaultBindings);

                globalScope.AddDefaultImpl(defaultImplDecl);
            }
        }
コード例 #17
0
        public static void PopulateMethod(ITranslationErrorHandler handler, Function fun)
        {
            if (fun.Body != null)
            {
                return;
            }

            var visitor = new FunctionBodyVisitor(handler, fun.Owner, fun);

            visitor.Visit(fun.SourceLocation);
        }
コード例 #18
0
ファイル: InferMachineCreates.cs プロジェクト: mbrukman/P
        public static void Populate(Machine machine, ITranslationErrorHandler handler)
        {
            InterfaceSet interfaces = new InterfaceSet();

            foreach (Function function in machine.Methods)
            {
                interfaces.AddInterfaces(InferCreates(function, handler));
            }

            machine.Creates = interfaces;
        }
コード例 #19
0
        private static void ValidateTransitions(ITranslationErrorHandler handler, Machine machine)
        {
            foreach (var state in machine.AllStates())
            {
                foreach (var pair in state.AllEventHandlers)
                {
                    var handledEvent = pair.Key;
                    switch (pair.Value)
                    {
                    case EventDoAction eventDoAction:
                        if (eventDoAction.Target != null)
                        {
                            ValidateEventPayloadToTransitionTarget(handler, eventDoAction.SourceLocation,
                                                                   handledEvent.PayloadType, eventDoAction.Target);
                        }

                        break;

                    case EventGotoState eventGotoState:
                        if (eventGotoState.Target.Entry != null)
                        {
                            ValidateEventPayloadToTransitionTarget(handler, eventGotoState.SourceLocation,
                                                                   handledEvent.PayloadType,
                                                                   eventGotoState.Target.Entry);
                        }

                        if (eventGotoState.TransitionFunction != null)
                        {
                            ValidateEventPayloadToTransitionTarget(handler, eventGotoState.SourceLocation,
                                                                   handledEvent.PayloadType,
                                                                   eventGotoState.TransitionFunction);
                        }

                        break;

                    case EventPushState eventPushState:
                        if (eventPushState.Target.Entry != null)
                        {
                            ValidateEventPayloadToTransitionTarget(handler, eventPushState.SourceLocation,
                                                                   handledEvent.PayloadType,
                                                                   eventPushState.Target.Entry);
                        }

                        break;
                    }
                }

                if (state.Exit?.Signature.Parameters.Count > 0)
                {
                    throw handler.IncorrectArgumentCount(state.SourceLocation, state.Exit.Signature.Parameters.Count,
                                                         0);
                }
            }
        }
コード例 #20
0
ファイル: FunctionValidator.cs プロジェクト: tushetodorov/P
 public static void CheckAllPathsReturn(ITranslationErrorHandler handler, Function function)
 {
     if (function.IsForeign)
     {
         return;
     }
     if (!SurelyReturns(function.Body) &&
         !function.Signature.ReturnType.IsSameTypeAs(PrimitiveType.Null))
     {
         throw handler.NotAllPathsReturn(function);
     }
 }
コード例 #21
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        private Scope(ITranslationErrorHandler handler, Scope parent = null)
        {
            this.handler = handler;
            parent?.children.Remove(this);
            Parent = parent;
            parent?.children.Add(this);

            EventSet eventSetWithHalt = new EventSet();

            eventSetWithHalt.AddEvent(new PEvent("halt", null));
            UniversalEventSet = parent == null ? eventSetWithHalt : parent.UniversalEventSet;
        }
コード例 #22
0
ファイル: MachineChecker.cs プロジェクト: yzhang90/P-1
        public static void ValidateNoStaticHandlers(ITranslationErrorHandler handler, Machine machine)
        {
            foreach (State state in machine.AllStates())
            {
                bool illegalUsage = state.Entry != null && IsStaticOrForeign(state.Entry);
                if (illegalUsage)
                {
                    throw handler.StaticFunctionNotAllowedAsHandler(state.SourceLocation,
                                                                    state.Entry.Name);
                }

                illegalUsage = state.Exit != null && IsStaticOrForeign(state.Exit);
                if (illegalUsage)
                {
                    throw handler.StaticFunctionNotAllowedAsHandler(state.SourceLocation,
                                                                    state.Exit.Name);
                }

                foreach (KeyValuePair <PEvent, AST.IStateAction> pair in state.AllEventHandlers)
                {
                    switch (pair.Value)
                    {
                    case EventDoAction eventDoAction:
                        if (eventDoAction.Target != null && IsStaticOrForeign(eventDoAction.Target))
                        {
                            throw handler.StaticFunctionNotAllowedAsHandler(eventDoAction.SourceLocation,
                                                                            eventDoAction.Target.Name);
                        }

                        break;

                    case EventGotoState eventGotoState:
                        if (eventGotoState.TransitionFunction != null &&
                            IsStaticOrForeign(eventGotoState.TransitionFunction))
                        {
                            throw handler.StaticFunctionNotAllowedAsHandler(eventGotoState.SourceLocation,
                                                                            eventGotoState.TransitionFunction.Name);
                        }

                        break;

                    case EventDefer _:
                    case EventIgnore _:
                    case EventPushState _:
                        break;

                    default:
                        throw handler.InternalError(pair.Value.SourceLocation,
                                                    new System.Exception("Unknown transition type parsed, report to the P team"));
                    }
                }
            }
        }
コード例 #23
0
ファイル: Validator.cs プロジェクト: zhaowei19920524/P
 private static PLanguageType GetStatePayload(State startState, ITranslationErrorHandler handler)
 {
     if (!(startState.Entry?.Signature.Parameters.Count > 0))
     {
         return(PrimitiveType.Null);
     }
     if (startState.Entry.Signature.Parameters.Count != 1)
     {
         throw handler.InternalError(startState.OwningMachine.SourceLocation,
                                     "Allowed start state entry with multiple parameters");
     }
     return(startState.Entry.Signature.Parameters[0].Type);
 }
コード例 #24
0
ファイル: MachineChecker.cs プロジェクト: yzhang90/P-1
        private static void ValidateTransitions(ITranslationErrorHandler handler, Machine machine)
        {
            foreach (State state in machine.AllStates())
            {
                foreach (KeyValuePair <PEvent, AST.IStateAction> pair in state.AllEventHandlers)
                {
                    PEvent handledEvent = pair.Key;
                    switch (pair.Value)
                    {
                    case EventDoAction eventDoAction:
                        if (eventDoAction.Target != null)
                        {
                            ValidateEventPayloadToTransitionTarget(handler: handler, sourceLocation: eventDoAction.SourceLocation,
                                                                   eventPayloadType: handledEvent.PayloadType, targetFunction: eventDoAction.Target);
                        }

                        break;

                    case EventGotoState eventGotoState:
                        if (eventGotoState.Target.Entry != null)
                        {
                            ValidateEventPayloadToTransitionTarget(handler: handler, sourceLocation: eventGotoState.SourceLocation,
                                                                   eventPayloadType: handledEvent.PayloadType, targetFunction: eventGotoState.Target.Entry);
                        }

                        if (eventGotoState.TransitionFunction != null)
                        {
                            ValidateEventPayloadToTransitionTarget(handler: handler, sourceLocation: eventGotoState.SourceLocation,
                                                                   eventPayloadType: handledEvent.PayloadType, targetFunction: eventGotoState.TransitionFunction);
                        }

                        break;

                    case EventPushState eventPushState:
                        if (eventPushState.Target.Entry != null)
                        {
                            ValidateEventPayloadToTransitionTarget(handler: handler, sourceLocation: eventPushState.SourceLocation,
                                                                   eventPayloadType: handledEvent.PayloadType, targetFunction: eventPushState.Target.Entry);
                        }

                        break;

                    case EventDefer _:
                    case EventIgnore _:
                    {
                        break;
                    }
                    }
                }
            }
        }
コード例 #25
0
 public static void CheckArgument(ITranslationErrorHandler handler, ParserRuleContext context,
                                  PLanguageType argumentType, IPExpr arg)
 {
     if (arg is ILinearRef linearRef)
     {
         if (linearRef.LinearType.Equals(LinearType.Swap) && !arg.Type.IsSameTypeAs(argumentType))
         {
             throw handler.TypeMismatch(context, arg.Type, argumentType);
         }
     }
     if (!argumentType.IsAssignableFrom(arg.Type))
     {
         throw handler.TypeMismatch(context, arg.Type, argumentType);
     }
 }
コード例 #26
0
ファイル: Analyzer.cs プロジェクト: zhaowei19920524/P
        public static Scope AnalyzeCompilationUnit(ITranslationErrorHandler handler, params PParser.ProgramContext[] programUnits)
        {
            // Step 1: Build the global scope of declarations
            Scope globalScope = BuildGlobalScope(handler, programUnits);

            // Step 2: Validate machine specifications
            foreach (Machine machine in globalScope.Machines)
            {
                Validator.ValidateMachine(handler, machine);
            }

            // Step 3: Fill function bodies
            List <Function> allFunctions = AllFunctions(globalScope).ToList();

            foreach (Function machineFunction in allFunctions)
            {
                FunctionBodyVisitor.PopulateMethod(handler, machineFunction);
            }

            // Step 4: Propagate purity properties
            ApplyPropagations(allFunctions,
                              CreatePropagation(fn => fn.CanCommunicate, (fn, value) => fn.CanCommunicate = value,
                                                true),
                              CreatePropagation(fn => fn.CanChangeState, (fn, value) => fn.CanChangeState = value,
                                                true));

            // Step 5: Verify purity invariants
            foreach (Function machineFunction in allFunctions)
            {
                if (machineFunction.Owner?.IsSpec == true && machineFunction.IsNondeterministic == true)
                {
                    throw handler.NonDeterministicFunctionInSpecMachine(machineFunction);
                }
                if (machineFunction.CanChangeState == true &&
                    (machineFunction.Role.HasFlag(FunctionRole.TransitionFunction) ||
                     machineFunction.Role.HasFlag(FunctionRole.ExitHandler)))
                {
                    throw handler.ChangedStateMidTransition(machineFunction.SourceLocation, machineFunction);
                }
            }

            // Step 6: Check linear type ownership
            LinearTypeChecker.AnalyzeMethods(handler, allFunctions);

            return(globalScope);
        }
コード例 #27
0
ファイル: MachineChecker.cs プロジェクト: yzhang90/P-1
        private static void ValidateHandlers(ITranslationErrorHandler handler, Machine machine)
        {
            foreach (var state in machine.AllStates())
            {
                if (state.Entry?.Signature.Parameters.Count > 1)
                {
                    throw handler.MoreThanOneParameterForHandlers(state.SourceLocation, state.Entry.Signature.Parameters.Count);
                }

                if (state.Exit?.Signature.Parameters.Count > 0)
                {
                    throw handler.ExitFunctionCannotTakeParameters(state.SourceLocation, state.Exit.Signature.Parameters.Count);
                }

                foreach (KeyValuePair <PEvent, AST.IStateAction> pair in state.AllEventHandlers)
                {
                    PEvent handledEvent = pair.Key;
                    switch (pair.Value)
                    {
                    case EventDoAction eventDoAction:
                        if (eventDoAction.Target != null && eventDoAction.Target.Signature.ParameterTypes.Count() > 1)
                        {
                            throw handler.MoreThanOneParameterForHandlers(eventDoAction.SourceLocation,
                                                                          eventDoAction.Target.Signature.ParameterTypes.Count());
                        }
                        break;

                    case EventGotoState eventGotoState:
                        if (eventGotoState.TransitionFunction != null && eventGotoState.TransitionFunction.Signature.ParameterTypes.Count() > 1)
                        {
                            throw handler.MoreThanOneParameterForHandlers(eventGotoState.SourceLocation,
                                                                          eventGotoState.TransitionFunction.Signature.ParameterTypes.Count());
                        }
                        break;

                    case EventPushState _:
                    case EventDefer _:
                    case EventIgnore _:
                    {
                        break;
                    }
                    }
                }
            }
        }
コード例 #28
0
        public static void ValidateNoStaticHandlers(ITranslationErrorHandler handler, Machine machine)
        {
            foreach (var state in machine.AllStates())
            {
                var illegalUsage = state.Entry != null && IsStaticOrForeign(state.Entry);
                if (illegalUsage)
                {
                    throw handler.StaticFunctionNotAllowedAsHandler(state.SourceLocation,
                                                                    state.Entry.Name);
                }

                illegalUsage = state.Exit != null && IsStaticOrForeign(state.Exit);
                if (illegalUsage)
                {
                    throw handler.StaticFunctionNotAllowedAsHandler(state.SourceLocation,
                                                                    state.Exit.Name);
                }

                foreach (var pair in state.AllEventHandlers)
                {
                    switch (pair.Value)
                    {
                    case EventDoAction eventDoAction:
                        if (eventDoAction.Target != null && IsStaticOrForeign(eventDoAction.Target))
                        {
                            throw handler.StaticFunctionNotAllowedAsHandler(eventDoAction.SourceLocation,
                                                                            eventDoAction.Target.Name);
                        }

                        break;

                    case EventGotoState eventGotoState:
                        if (eventGotoState.TransitionFunction != null &&
                            IsStaticOrForeign(eventGotoState.TransitionFunction))
                        {
                            throw handler.StaticFunctionNotAllowedAsHandler(eventGotoState.SourceLocation,
                                                                            eventGotoState.TransitionFunction.Name);
                        }

                        break;
                    }
                }
            }
        }
コード例 #29
0
ファイル: Validator.cs プロジェクト: zhaowei19920524/P
        public static void ValidateMachine(ITranslationErrorHandler handler, Machine machine)
        {
            State         startState            = FindStartState(machine, handler);
            PLanguageType startStatePayloadType = GetStatePayload(startState, handler);

            if (!startStatePayloadType.IsSameTypeAs(machine.PayloadType))
            {
                throw handler.InternalError(machine.SourceLocation,
                                            "machine payload type is not the same as start state's entry payload type");
            }

            foreach (Interface machineInterface in machine.Interfaces)
            {
                if (!machine.PayloadType.IsAssignableFrom(machineInterface.PayloadType))
                {
                    // TODO: add special "invalid machine interface" error
                    throw handler.TypeMismatch(machine.StartState.Entry?.SourceLocation ?? machine.SourceLocation,
                                               machine.PayloadType,
                                               machineInterface.PayloadType);
                }
            }
        }
コード例 #30
0
ファイル: Analyzer.cs プロジェクト: zhaowei19920524/P
        private static Scope BuildGlobalScope(ITranslationErrorHandler handler, PParser.ProgramContext[] programUnits)
        {
            var globalScope         = new Scope(handler);
            var nodesToDeclarations = new ParseTreeProperty <IPDecl>();

            // Add built-in events to the table.
            globalScope.Put("halt", (PParser.EventDeclContext)null);
            globalScope.Put("null", (PParser.EventDeclContext)null);

            // Step 1: Create mapping of names to declaration stubs
            foreach (PParser.ProgramContext programUnit in programUnits)
            {
                DeclarationStubVisitor.PopulateStubs(globalScope, programUnit, nodesToDeclarations);
            }

            // Step 2: Validate declarations and fill with types
            foreach (PParser.ProgramContext programUnit in programUnits)
            {
                DeclarationVisitor.PopulateDeclarations(handler, globalScope, programUnit, nodesToDeclarations);
            }
            return(globalScope);
        }