Split interceptor emitter.

sdk/lib/_internal/compiler/implementation/js_emitter/interceptor_emitter.dart

Index: sdk/lib/_internal/compiler/implementation/js_emitter/interceptor_emitter.dart
diff --git a/sdk/lib/_internal/compiler/implementation/js_emitter/interceptor_emitter.dart b/sdk/lib/_internal/compiler/implementation/js_emitter/interceptor_emitter.dart
deleted file mode 100644
index 603e93b8eb230cca54dd93113bb9649484aab3d9..0000000000000000000000000000000000000000
--- a/sdk/lib/_internal/compiler/implementation/js_emitter/interceptor_emitter.dart
+++ /dev/null
@@ -1,458 +0,0 @@
-// Copyright (c) 2013, 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 dart2js.js_emitter;
-
-class InterceptorEmitter extends CodeEmitterHelper {
-  final Set<String> interceptorInvocationNames = new Set<String>();
-
-  void recordMangledNameOfMemberMethod(FunctionElement member, String name) {
-    if (backend.isInterceptedMethod(member)) {
-      interceptorInvocationNames.add(name);
-    }
-  }
-
-  Set<ClassElement> interceptorsReferencedFromConstants() {
-    Set<ClassElement> classes = new Set<ClassElement>();
-    JavaScriptConstantCompiler handler = backend.constants;
-    List<Constant> constants = handler.getConstantsForEmission();
-    for (Constant constant in constants) {
-      if (constant is InterceptorConstant) {
-        InterceptorConstant interceptorConstant = constant;
-        classes.add(interceptorConstant.dispatchedType.element);
-      }
-    }
-    return classes;
-  }
-
-  void emitGetInterceptorMethod(CodeBuffer buffer,
-                                String key,
-                                Set<ClassElement> classes) {
-    jsAst.Expression interceptorFor(ClassElement cls) {
-      return js('#.prototype', namer.elementAccess(cls));
-    }
-
-    /**
-     * Build a JavaScrit AST node for doing a type check on
-     * [cls]. [cls] must be a non-native interceptor class.
-     */
-    jsAst.Statement buildInterceptorCheck(ClassElement cls) {
-      jsAst.Expression condition;
-      assert(backend.isInterceptorClass(cls));
-      if (cls == backend.jsBoolClass) {
-        condition = js('(typeof receiver) == "boolean"');
-      } else if (cls == backend.jsIntClass ||
-                 cls == backend.jsDoubleClass ||
-                 cls == backend.jsNumberClass) {
-        throw 'internal error';
-      } else if (cls == backend.jsArrayClass ||
-                 cls == backend.jsMutableArrayClass ||
-                 cls == backend.jsFixedArrayClass ||
-                 cls == backend.jsExtendableArrayClass) {
-        condition = js('receiver.constructor == Array');
-      } else if (cls == backend.jsStringClass) {
-        condition = js('(typeof receiver) == "string"');
-      } else if (cls == backend.jsNullClass) {
-        condition = js('receiver == null');
-      } else {
-        throw 'internal error';
-      }
-      return js.statement('if (#) return #', [condition, interceptorFor(cls)]);
-    }
-
-    bool hasArray = false;
-    bool hasBool = false;
-    bool hasDouble = false;
-    bool hasInt = false;
-    bool hasNull = false;
-    bool hasNumber = false;
-    bool hasString = false;
-    bool hasNative = false;
-    bool anyNativeClasses = compiler.enqueuer.codegen.nativeEnqueuer
-          .hasInstantiatedNativeClasses();
-
-    for (ClassElement cls in classes) {
-      if (cls == backend.jsArrayClass ||
-          cls == backend.jsMutableArrayClass ||
-          cls == backend.jsFixedArrayClass ||
-          cls == backend.jsExtendableArrayClass) hasArray = true;
-      else if (cls == backend.jsBoolClass) hasBool = true;
-      else if (cls == backend.jsDoubleClass) hasDouble = true;
-      else if (cls == backend.jsIntClass) hasInt = true;
-      else if (cls == backend.jsNullClass) hasNull = true;
-      else if (cls == backend.jsNumberClass) hasNumber = true;
-      else if (cls == backend.jsStringClass) hasString = true;
-      else {
-        // The set of classes includes classes mixed-in to interceptor classes
-        // and user extensions of native classes.
-        //
-        // The set of classes also includes the 'primitive' interceptor
-        // PlainJavaScriptObject even when it has not been resolved, since it is
-        // only resolved through the reference in getNativeInterceptor when
-        // getNativeInterceptor is marked as used.  Guard against probing
-        // unresolved PlainJavaScriptObject by testing for anyNativeClasses.
-
-        if (anyNativeClasses) {
-          if (Elements.isNativeOrExtendsNative(cls)) hasNative = true;
-        }
-      }
-    }
-    if (hasDouble) {
-      hasNumber = true;
-    }
-    if (hasInt) hasNumber = true;
-
-    if (classes.containsAll(backend.interceptedClasses)) {
-      // I.e. this is the general interceptor.
-      hasNative = anyNativeClasses;
-    }
-
-    List<jsAst.Statement> statements = <jsAst.Statement>[];
-
-    if (hasNumber) {
-      jsAst.Statement whenNumber;
-
-      /// Note: there are two number classes in play: Dart's [num],
-      /// and JavaScript's Number (typeof receiver == 'number').  This
-      /// is the fallback used when we have determined that receiver
-      /// is a JavaScript Number.
-      jsAst.Expression interceptorForNumber = interceptorFor(
-          hasDouble ? backend.jsDoubleClass : backend.jsNumberClass);
-
-      if (hasInt) {
-        whenNumber = js.statement('''{
-            if (Math.floor(receiver) == receiver) return #;
-            return #;
-        }''', [interceptorFor(backend.jsIntClass), interceptorForNumber]);
-      } else {
-        whenNumber = js.statement('return #', interceptorForNumber);
-      }
-      statements.add(
-          js.statement('if (typeof receiver == "number") #;', whenNumber));
-    }
-
-    if (hasString) {
-      statements.add(buildInterceptorCheck(backend.jsStringClass));
-    }
-    if (hasNull) {
-      statements.add(buildInterceptorCheck(backend.jsNullClass));
-    } else {
-      // Returning "undefined" or "null" here will provoke a JavaScript
-      // TypeError which is later identified as a null-error by
-      // [unwrapException] in js_helper.dart.
-      statements.add(
-          js.statement('if (receiver == null) return receiver'));
-    }
-    if (hasBool) {
-      statements.add(buildInterceptorCheck(backend.jsBoolClass));
-    }
-    // TODO(ahe): It might be faster to check for Array before
-    // function and bool.
-    if (hasArray) {
-      statements.add(buildInterceptorCheck(backend.jsArrayClass));
-    }
-
-    if (hasNative) {
-      statements.add(js.statement(r'''{
-          if (typeof receiver != "object") return receiver;
-          if (receiver instanceof #) return receiver;
-          return #(receiver);
-      }''', [
-          namer.elementAccess(compiler.objectClass),
-          namer.elementAccess(backend.getNativeInterceptorMethod)]));
-
-    } else {
-      ClassElement jsUnknown = backend.jsUnknownJavaScriptObjectClass;
-      if (compiler.codegenWorld.instantiatedClasses.contains(jsUnknown)) {
-        statements.add(
-            js.statement('if (!(receiver instanceof #)) return #;',
-                [namer.elementAccess(compiler.objectClass),
-                 interceptorFor(jsUnknown)]));
-      }
-
-      statements.add(js.statement('return receiver'));
-    }
-
-    buffer.write(jsAst.prettyPrint(
-        js('''${namer.globalObjectFor(backend.interceptorsLibrary)}.# =
-              function(receiver) { #; }''',
-            [key, statements]),
-        compiler));
-    buffer.write(N);
-  }
-
-  /**
-   * Emit all versions of the [:getInterceptor:] method.
-   */
-  void emitGetInterceptorMethods(CodeBuffer buffer) {
-    emitter.addComment('getInterceptor methods', buffer);
-    Map<String, Set<ClassElement>> specializedGetInterceptors =
-        backend.specializedGetInterceptors;
-    for (String name in specializedGetInterceptors.keys.toList()..sort()) {
-      Set<ClassElement> classes = specializedGetInterceptors[name];
-      emitGetInterceptorMethod(buffer, name, classes);
-    }
-  }
-
-  // Returns a statement that takes care of performance critical
-  // common case for a one-shot interceptor, or null if there is no
-  // fast path.
-  jsAst.Statement fastPathForOneShotInterceptor(Selector selector,
-                                                Set<ClassElement> classes) {
-
-    if (selector.isOperator) {
-      String name = selector.name;
-      if (name == '==') {
-        return js.statement('''{
-          if (receiver == null) return a0 == null;
-          if (typeof receiver != "object")
-            return a0 != null && receiver === a0;
-        }''');
-      }
-      if (!classes.contains(backend.jsIntClass)
-          && !classes.contains(backend.jsNumberClass)
-          && !classes.contains(backend.jsDoubleClass)) {
-        return null;
-      }
-      if (selector.argumentCount == 1) {
-        // The following operators do not map to a JavaScript operator.
-        if (name == '~/' || name == '<<' || name == '%' || name == '>>') {
-          return null;
-        }
-        jsAst.Expression result = js('receiver $name a0');
-        if (name == '&' || name == '|' || name == '^') {
-          result = js('# >>> 0', result);
-        }
-        return js.statement(
-            'if (typeof receiver == "number" && typeof a0 == "number")'
-            '  return #;',
-            result);
-      } else if (name == 'unary-') {
-        return js.statement(
-            'if (typeof receiver == "number") return -receiver');
-      } else {
-        assert(name == '~');
-        return js.statement('''
-          if (typeof receiver == "number" && Math.floor(receiver) == receiver)
-            return (~receiver) >>> 0;
-          ''');
-      }
-    } else if (selector.isIndex || selector.isIndexSet) {
-      // For an index operation, this code generates:
-      //
-      //    if (receiver.constructor == Array || typeof receiver == "string") {
-      //      if (a0 >>> 0 === a0 && a0 < receiver.length) {
-      //        return receiver[a0];
-      //      }
-      //    }
-      //
-      // For an index set operation, this code generates:
-      //
-      //    if (receiver.constructor == Array && !receiver.immutable$list) {
-      //      if (a0 >>> 0 === a0 && a0 < receiver.length) {
-      //        return receiver[a0] = a1;
-      //      }
-      //    }
-      bool containsArray = classes.contains(backend.jsArrayClass);
-      bool containsString = classes.contains(backend.jsStringClass);
-      bool containsJsIndexable =
-          backend.jsIndexingBehaviorInterface.isResolved && classes.any((cls) {
-        return compiler.world.isSubtypeOf(cls,
-            backend.jsIndexingBehaviorInterface);
-      });
-      // The index set operator requires a check on its set value in
-      // checked mode, so we don't optimize the interceptor if the
-      // compiler has type assertions enabled.
-      if (selector.isIndexSet
-          && (compiler.enableTypeAssertions || !containsArray)) {
-        return null;
-      }
-      if (!containsArray && !containsString) {
-        return null;
-      }
-      jsAst.Expression arrayCheck = js('receiver.constructor == Array');
-      jsAst.Expression indexableCheck =
-          backend.generateIsJsIndexableCall(js('receiver'), js('receiver'));
-
-      jsAst.Expression orExp(left, right) {
-        return left == null ? right : js('# || #', [left, right]);
-      }
-
-      if (selector.isIndex) {
-        jsAst.Expression typeCheck;
-        if (containsArray) {
-          typeCheck = arrayCheck;
-        }
-
-        if (containsString) {
-          typeCheck = orExp(typeCheck, js('typeof receiver == "string"'));
-        }
-
-        if (containsJsIndexable) {
-          typeCheck = orExp(typeCheck, indexableCheck);
-        }
-
-        return js.statement('''
-          if (#)
-            if ((a0 >>> 0) === a0 && a0 < receiver.length)
-              return receiver[a0];
-          ''', typeCheck);
-      } else {
-        jsAst.Expression typeCheck;
-        if (containsArray) {
-          typeCheck = arrayCheck;
-        }
-
-        if (containsJsIndexable) {
-          typeCheck = orExp(typeCheck, indexableCheck);
-        }
-
-        return js.statement(r'''
-          if (# && !receiver.immutable$list &&
-              (a0 >>> 0) === a0 && a0 < receiver.length)
-            return receiver[a0] = a1;
-          ''', typeCheck);
-      }
-    }
-    return null;
-  }
-
-  void emitOneShotInterceptors(CodeBuffer buffer) {
-    List<String> names = backend.oneShotInterceptors.keys.toList();
-    names.sort();
-    for (String name in names) {
-      Selector selector = backend.oneShotInterceptors[name];
-      Set<ClassElement> classes =
-          backend.getInterceptedClassesOn(selector.name);
-      String getInterceptorName =
-          namer.getInterceptorName(backend.getInterceptorMethod, classes);
-
-      List<String> parameterNames = <String>[];
-      parameterNames.add('receiver');
-
-      if (selector.isSetter) {
-        parameterNames.add('value');
-      } else {
-        for (int i = 0; i < selector.argumentCount; i++) {
-          parameterNames.add('a$i');
-        }
-      }
-
-      String invocationName = backend.namer.invocationName(selector);
-      String globalObject = namer.globalObjectFor(backend.interceptorsLibrary);
-
-      jsAst.Statement optimizedPath =
-          fastPathForOneShotInterceptor(selector, classes);
-      if (optimizedPath == null) optimizedPath = js.statement(';');
-
-      jsAst.Expression assignment = js('${globalObject}.# = function(#) {'
-          '  #;'
-          '  return #.#(receiver).#(#) }',
-          [name, parameterNames,
-           optimizedPath,
-           globalObject, getInterceptorName, invocationName, parameterNames]);
-
-      buffer.write(jsAst.prettyPrint(assignment, compiler));
-      buffer.write(N);
-    }
-  }
-
-  /**
-   * If [JSInvocationMirror._invokeOn] has been compiled, emit all the
-   * possible selector names that are intercepted into the
-   * [interceptedNames] top-level variable. The implementation of
-   * [_invokeOn] will use it to determine whether it should call the
-   * method with an extra parameter.
-   */
-  void emitInterceptedNames(CodeBuffer buffer) {
-    // TODO(ahe): We should not generate the list of intercepted names at
-    // compile time, it can be generated automatically at runtime given
-    // subclasses of Interceptor (which can easily be identified).
-    if (!compiler.enabledInvokeOn) return;
-
-    // TODO(ahe): We should roll this into
-    // [emitStaticNonFinalFieldInitializations].
-    String name = backend.namer.getNameOfGlobalField(backend.interceptedNames);
-
-    int index = 0;
-    var invocationNames = interceptorInvocationNames.toList()..sort();
-    List<jsAst.ArrayElement> elements = invocationNames.map(
-      (String invocationName) {
-        jsAst.Literal str = js.string(invocationName);
-        return new jsAst.ArrayElement(index++, str);
-      }).toList();
-    jsAst.ArrayInitializer array =
-        new jsAst.ArrayInitializer(invocationNames.length, elements);
-
-    jsAst.Expression assignment =
-        js('${emitter.isolateProperties}.# = #', [name, array]);
-
-    buffer.write(jsAst.prettyPrint(assignment, compiler));
-    buffer.write(N);
-  }
-
-  /**
-   * Emit initializer for [mapTypeToInterceptor] data structure used by
-   * [findInterceptorForType].  See declaration of [mapTypeToInterceptor] in
-   * `interceptors.dart`.
-   */
-  void emitMapTypeToInterceptor(CodeBuffer buffer) {
-    // TODO(sra): Perhaps inject a constant instead?
-    CustomElementsAnalysis analysis = backend.customElementsAnalysis;
-    if (!analysis.needsTable) return;
-
-    List<jsAst.Expression> elements = <jsAst.Expression>[];
-    JavaScriptConstantCompiler handler = backend.constants;
-    List<Constant> constants =
-        handler.getConstantsForEmission(emitter.compareConstants);
-    for (Constant constant in constants) {
-      if (constant is TypeConstant) {
-        TypeConstant typeConstant = constant;
-        Element element = typeConstant.representedType.element;
-        if (element is ClassElement) {
-          ClassElement classElement = element;
-          if (!analysis.needsClass(classElement)) continue;
-
-          elements.add(emitter.constantReference(constant));
-          elements.add(namer.elementAccess(classElement));
-
-          // Create JavaScript Object map for by-name lookup of generative
-          // constructors.  For example, the class A has three generative
-          // constructors
-          //
-          //     class A {
-          //       A() {}
-          //       A.foo() {}
-          //       A.bar() {}
-          //     }
-          //
-          // Which are described by the map
-          //
-          //     {"": A.A$, "foo": A.A$foo, "bar": A.A$bar}
-          //
-          // We expect most of the time the map will be a singleton.
-          var properties = [];
-          for (Element member in analysis.constructors(classElement)) {
-            properties.add(
-                new jsAst.Property(
-                    js.string(member.name),
-                    backend.namer.elementAccess(member)));
-          }
-
-          var map = new jsAst.ObjectInitializer(properties);
-          elements.add(map);
-        }
-      }
-    }
-
-    jsAst.ArrayInitializer array = new jsAst.ArrayInitializer.from(elements);
-    String name =
-        backend.namer.getNameOfGlobalField(backend.mapTypeToInterceptor);
-    jsAst.Expression assignment =
-        js('${emitter.isolateProperties}.# = #', [name, array]);
-
-    buffer.write(jsAst.prettyPrint(assignment, compiler));
-    buffer.write(N);
-  }
-}