Support runtime check of function types.

sdk/lib/_internal/compiler/implementation/ssa/builder.dart

 // Copyright (c) 2012, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 part of ssa;
 
 /**
  * A special element for the extra parameter taken by intercepted
  * methods. We need to override [Element.computeType] because our
  * optimizers may look at its declared type.
@@ skipping 1765 matching lines @@
      HType subtype = new HType.subtype(type, compiler);
      HInstruction representations = buildTypeArgumentRepresentations(type);
      add(representations);
      return new HTypeConversion.withTypeRepresentation(type, kind, subtype,
           original, representations);
     } else if (type.kind == TypeKind.TYPE_VARIABLE) {
       HType subtype = original.instructionType;
       HInstruction typeVariable = addTypeVariableReference(type);
       return new HTypeConversion.withTypeRepresentation(type, kind, subtype,
           original, typeVariable);
+    } else if (type.kind == TypeKind.FUNCTION) {
+      HType subtype = original.instructionType;
+      bool contextIsTypeArguments = false;
+      HInstruction context;
+      if (type.containsTypeVariables) {
+        if (currentElement.isInstanceMember()) {
+          context = localsHandler.readThis();
+        } else {
+          ClassElement contextClass = Types.getClassContext(type);
+          List<HInstruction> inputs = <HInstruction>[];
+          for (Link<DartType> link = contextClass.typeVariables;
+              !link.isEmpty;
+              link = link.tail) {
+            inputs.add(addTypeVariableReference(link.head));
+          }
+          context = buildLiteralList(inputs);
+          add(context);
+          contextIsTypeArguments = true;
+        }
+      } else {
+        context = graph.addConstantNull(compiler);
+      }
+      return new HTypeConversion.withContext(type, kind, subtype,

[karlklose, 2013/06/20 07:32:55]

I'd rather not create a new conversion withContext for the case of no context.
Couldn't you just create a normal conversion and get rid of the else-branch in
1805?

[Johnni Winther, 2013/06/21 12:19:15]

Done.

+          original, context, contextIsTypeArguments: contextIsTypeArguments);
     } else {
       return original.convertType(compiler, type, kind);
     }
   }
 
   HInstruction potentiallyCheckType(HInstruction original, DartType type,
       { int kind: HTypeConversion.CHECKED_MODE_CHECK }) {
     if (!compiler.enableTypeAssertions) return original;
+    type = type.unalias(compiler);
     HInstruction other = buildTypeConversion(original, type, kind);
     if (other != original) add(other);
+    compiler.enqueuer.codegen.registerIsCheck(type, work.resolutionTree);
     return other;
   }
 
   HGraph closeFunction() {
     // TODO(kasperl): Make this goto an implicit return.
     if (!isAborted()) closeAndGotoExit(new HGoto());
     graph.finalize();
     return graph;
   }
 
@@ skipping 625 matching lines @@
         Element capturedLocal = nestedClosureData.capturedFieldMapping[member];
         assert(capturedLocal != null);
         capturedVariables.add(localsHandler.readLocal(capturedLocal));
       }
     });
 
     HType type = new HType.nonNullExact(
         compiler.functionClass.computeType(compiler),
         compiler);
     push(new HForeignNew(closureClassElement, type, capturedVariables));
+
+    Element methodElement = nestedClosureData.closureElement;
+    if (compiler.backend.methodNeedsRti(methodElement)) {
+      compiler.backend.registerGenericClosure(
+          methodElement, compiler.enqueuer.codegen, work.resolutionTree);
+    }
   }
 
   visitFunctionDeclaration(FunctionDeclaration node) {
     assert(isReachable);
     visit(node.function);
     localsHandler.updateLocal(elements[node], pop());
   }
 
   visitIdentifier(Identifier node) {
     if (node.isThis()) {
@@ skipping 263 matching lines @@
           inputs.add(runtimeType);
         }));
       }
       String template = '[${templates.join(', ')}]';
       HInstruction representation =
         createForeign(template, backend.readableArrayType, inputs);
       return representation;
     }
   }
 
-  visitOperatorSend(node) {
+  visitOperatorSend(Send node) {
     Operator op = node.selector;
     if (const SourceString("[]") == op.source) {
       visitDynamicSend(node);
     } else if (const SourceString("&&") == op.source ||
                const SourceString("||") == op.source) {
       visitLogicalAndOr(node, op);
     } else if (const SourceString("!") == op.source) {
       visitLogicalNot(node);
     } else if (node.argumentsNode is Prefix) {
       visitUnary(node, op);
     } else if (const SourceString("is") == op.source) {
       visitIsSend(node);
     } else if (const SourceString("as") == op.source) {
       visit(node.receiver);
       HInstruction expression = pop();
       Node argument = node.arguments.head;
       TypeAnnotation typeAnnotation = argument.asTypeAnnotation();
       DartType type = elements.getType(typeAnnotation);
+      type = type.unalias(compiler);

[karlklose, 2013/06/20 07:32:55]

Move to buildTypeConversion?

[Johnni Winther, 2013/06/21 12:19:15]

Done.

       HInstruction converted = buildTypeConversion(
           expression, type, HTypeConversion.CAST_TYPE_CHECK);
       if (converted != expression) add(converted);
       stack.add(converted);
     } else {
       visit(node.receiver);
       visit(node.argumentsNode);
       var right = pop();
       var left = pop();
       visitBinary(left, op, right, elements.getSelector(node), node);
     }
   }
 
   void visitIsSend(Send node) {
     visit(node.receiver);
     HInstruction expression = pop();
     bool isNot = node.isIsNotCheck;
     DartType type = elements.getType(node.typeAnnotationFromIsCheck);
+    type = type.unalias(compiler);

[karlklose, 2013/06/20 07:32:55]

Move to buildIsNode? isMalformed on an unaliased type could simply unalias
itself and call isMalformed on the result.

[Johnni Winther, 2013/06/21 12:19:15]

Currently we can't. And this will be removed when the new malformedness is
implemented.

     if (type.isMalformed) {
       String reasons = Types.fetchReasonsFromMalformedType(type);
       if (compiler.enableTypeAssertions) {
         generateMalformedSubtypeError(node, expression, type, reasons);
       } else {
         generateRuntimeError(node, '$type is malformed: $reasons');
       }
     } else {
       HInstruction instruction = buildIsNode(node, type, expression);
       if (isNot) {
         add(instruction);
         instruction = new HNot(instruction);
       }
       push(instruction);
     }
   }
 
   HInstruction buildIsNode(Node node, DartType type, HInstruction expression) {
-    if (type.kind == TypeKind.TYPE_VARIABLE) {
+    if (type.kind == TypeKind.FUNCTION) {
+      Element checkFunctionSubtype = backend.getCheckFunctionSubtype();
+
+      HInstruction signatureName = graph.addConstantString(
+          new DartString.literal(backend.namer.getFunctionTypeName(type)),
+          node, compiler);
+
+      HInstruction contextName;
+      HInstruction context;
+      HInstruction typeArguments;
+      if (type.containsTypeVariables) {
+        ClassElement contextClass = Types.getClassContext(type);
+        contextName = graph.addConstantString(
+            new DartString.literal(backend.namer.getName(contextClass)),
+            node, compiler);
+        if (currentElement.isInstanceMember()) {
+          context = localsHandler.readThis();
+          typeArguments = graph.addConstantNull(compiler);
+        } else {
+          context = graph.addConstantNull(compiler);

[karlklose, 2013/06/20 07:32:55]

This code (and the else-branch) could be shared with buildTypeConversion.

[Johnni Winther, 2013/06/21 12:19:15]

Added a buildTypeVariableList method used by both buildTypeConversion and
buildIsNode.

+          List<HInstruction> inputs = <HInstruction>[];
+          for (Link<DartType> link = contextClass.typeVariables;
+               !link.isEmpty;
+               link = link.tail) {
+            inputs.add(addTypeVariableReference(link.head));
+          }
+          typeArguments = buildLiteralList(inputs);
+          add(typeArguments);
+        }
+      } else {
+        contextName = graph.addConstantNull(compiler);
+        context = graph.addConstantNull(compiler);
+        typeArguments = graph.addConstantNull(compiler);
+      }
+
+      List<HInstruction> inputs = <HInstruction>[expression,
+                                                 signatureName,
+                                                 contextName,
+                                                 context,
+                                                 typeArguments];
+      pushInvokeStatic(node, checkFunctionSubtype, inputs, HType.BOOLEAN);

[karlklose, 2013/06/20 07:32:55]

Could you move this to the codegen by creating a new version of HIs?

[Johnni Winther, 2013/06/21 12:19:15]

The generation is already handle in codegen. We just prepare the needed call
here.

+      HInstruction call = pop();
+      return new HIs(type, <HInstruction>[expression, call],
+          HIs.COMPOUND_CHECK);
+    } else if (type.kind == TypeKind.TYPE_VARIABLE) {
       HInstruction runtimeType = addTypeVariableReference(type);
       Element helper = backend.getCheckSubtypeOfRuntimeType();
       List<HInstruction> inputs = <HInstruction>[expression, runtimeType];
       pushInvokeStatic(null, helper, inputs, HType.BOOLEAN);
       HInstruction call = pop();
       return new HIs(type, <HInstruction>[expression, call],
                      HIs.VARIABLE_CHECK);
     } else if (RuntimeTypes.hasTypeArguments(type)) {
       ClassElement element = type.element;
       Element helper = backend.getCheckSubtype();
@@ skipping 177 matching lines @@
       Element element = compiler.isolateHelperLibrary.find(
           const SourceString('_currentIsolate'));
       if (element == null) {
         compiler.cancel(
             'Isolate library and compiler mismatch', node: node);
       }
       pushInvokeStatic(null, element, [], HType.UNKNOWN);
     }
   }
 
+  void handleForeignJsSetupObject(Send node) {
+    if (!node.arguments.isEmpty) {
+      compiler.cancel(
+          'Too many arguments to JS_SETUP_OBJECT', node: node);
+    }
+
+    String name = backend.namer.SETUP_OBJECT;
+    push(new HForeign(new js.LiteralString(name),
+                      HType.UNKNOWN,
+                      <HInstruction>[]));
+  }
+
   void handleForeignJsCallInIsolate(Send node) {
     Link<Node> link = node.arguments;
     if (!compiler.hasIsolateSupport()) {
       // If the isolate library is not used, we just invoke the
       // closure.
       visit(link.tail.head);
       Selector selector = new Selector.callClosure(0);
       push(new HInvokeClosure(selector, <HInstruction>[pop()]));
     } else {
       // Call a helper method from the isolate library.
@@ skipping 91 matching lines @@
                       <HInstruction>[]));
   }
 
   visitForeignSend(Send node) {
     Selector selector = elements.getSelector(node);
     SourceString name = selector.name;
     if (name == const SourceString('JS')) {
       handleForeignJs(node);
     } else if (name == const SourceString('JS_CURRENT_ISOLATE_CONTEXT')) {
       handleForeignJsCurrentIsolateContext(node);
+    } else if (name == const SourceString('JS_SETUP_OBJECT')) {
+      handleForeignJsSetupObject(node);
     } else if (name == const SourceString('JS_CALL_IN_ISOLATE')) {
       handleForeignJsCallInIsolate(node);
     } else if (name == const SourceString('DART_CLOSURE_TO_JS')) {
       handleForeignDartClosureToJs(node, 'DART_CLOSURE_TO_JS');
     } else if (name == const SourceString('RAW_DART_FUNCTION_REF')) {
       handleForeignRawFunctionRef(node, 'RAW_DART_FUNCTION_REF');
     } else if (name == const SourceString('JS_SET_CURRENT_ISOLATE')) {
       handleForeignSetCurrentIsolate(node);
     } else if (name == const SourceString('JS_CREATE_ISOLATE')) {
       handleForeignCreateIsolate(node);
     } else if (name == const SourceString('JS_OPERATOR_IS_PREFIX')) {
       stack.add(addConstantString(node, backend.namer.operatorIsPrefix()));
     } else if (name == const SourceString('JS_OBJECT_CLASS_NAME')) {
       String name = backend.namer.getRuntimeTypeName(compiler.objectClass);
       stack.add(addConstantString(node, name));
+    } else if (name == const SourceString('JS_FUNCTION_CLASS_NAME')) {
+      String name = backend.namer.getRuntimeTypeName(compiler.functionClass);
+      stack.add(addConstantString(node, name));
     } else if (name == const SourceString('JS_OPERATOR_AS_PREFIX')) {
       stack.add(addConstantString(node, backend.namer.operatorAsPrefix()));
+    } else if (name == const SourceString('JS_SIGNATURE_NAME')) {
+      stack.add(addConstantString(node, backend.namer.operatorSignature()));
+    } else if (name == const SourceString('JS_FUNCTION_TYPE_TAG')) {
+      stack.add(addConstantString(node, backend.namer.functionTypeTag()));
+    } else if (name == const SourceString('JS_FUNCTION_TYPE_VOID_RETURN_TAG')) {
+      stack.add(addConstantString(node,
+                                  backend.namer.functionTypeVoidReturnTag()));
+    } else if (name == const SourceString('JS_FUNCTION_TYPE_RETURN_TYPE_TAG')) {
+      stack.add(addConstantString(node,
+                                  backend.namer.functionTypeReturnTypeTag()));
+    } else if (name ==
+               const SourceString('JS_FUNCTION_TYPE_REQUIRED_PARAMETERS_TAG')) {
+      stack.add(addConstantString(node,
+          backend.namer.functionTypeRequiredParametersTag()));
+    } else if (name ==
+               const SourceString('JS_FUNCTION_TYPE_OPTIONAL_PARAMETERS_TAG')) {
+      stack.add(addConstantString(node,
+          backend.namer.functionTypeOptionalParametersTag()));
+    } else if (name ==
+               const SourceString('JS_FUNCTION_TYPE_NAMED_PARAMETERS_TAG')) {
+      stack.add(addConstantString(node,
+          backend.namer.functionTypeNamedParametersTag()));
     } else if (name == const SourceString('JS_DART_OBJECT_CONSTRUCTOR')) {
       handleForeignDartObjectJsConstructorFunction(node);
     } else if (name == const SourceString('JS_IS_INDEXABLE_FIELD_NAME')) {
       Element element = compiler.findHelper(
           const SourceString('JavaScriptIndexingBehavior'));
       stack.add(addConstantString(node, backend.namer.operatorIs(element)));
     } else if (name == const SourceString('JS_CURRENT_ISOLATE')) {
       handleForeignJsCurrentIsolate(node);
     } else {
       throw "Unknown foreign: ${selector}";
@@ skipping 96 matching lines @@
   /**
    * Generate code to extract the type arguments from the object, substitute
    * them as an instance of the type we are testing against (if necessary), and
    * extract the type argument by the index of the variable in the list of type
    * variables for that class.
    */
   HInstruction readTypeVariable(ClassElement cls,
                                 TypeVariableElement variable) {
     assert(currentElement.isInstanceMember());
     int index = RuntimeTypes.getTypeVariableIndex(variable);
-    String substitutionNameString = backend.namer.substitutionName(cls);
+    String substitutionNameString = backend.namer.getName(cls);

[karlklose, 2013/06/20 07:32:55]

How does this work? substitutionName contains the asPrefix.

[Johnni Winther, 2013/06/21 12:19:15]

getRuntimeTypeArgument has been changed to take the name of the class instead.
The helper then use this to create the is/as-predicate names as needed.

     HInstruction substitutionName = graph.addConstantString(
         new LiteralDartString(substitutionNameString), null, compiler);
     HInstruction target = localsHandler.readThis();
-    HInstruction substitution = createForeign('#[#]', HType.UNKNOWN,
-        <HInstruction>[target, substitutionName]);
-    add(substitution);
     pushInvokeStatic(null,
                      backend.getGetRuntimeTypeArgument(),
                      [target,
-                      substitution,
+                      substitutionName,
                       graph.addConstantInt(index, compiler)],
                       HType.UNKNOWN);
     return pop();
   }
 
   /**
    * Helper to create an instruction that gets the value of a type variable.
    */
   HInstruction addTypeVariableReference(TypeVariableType type) {
     Element member = currentElement;
@@ skipping 2138 matching lines @@
           new HSubGraphBlockInformation(elseBranch.graph));
 
     HBasicBlock conditionStartBlock = conditionBranch.block;
     conditionStartBlock.setBlockFlow(info, joinBlock);
     SubGraph conditionGraph = conditionBranch.graph;
     HIf branch = conditionGraph.end.last;
     assert(branch is HIf);
     branch.blockInformation = conditionStartBlock.blockFlow;
   }
 }