Linter Demo

Errors: 2

Warnings: 5

File: /home/fstrocco/Dart/dart/benchmark/compiler/lib/src/inferrer/node_tracer.dart

// 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 type_graph_inferrer; // A set of selectors we know do not escape the elements inside the // list. Set<String> doesNotEscapeListSet = new Set<String>.from( const <String>[ // From Object. '==', 'hashCode', 'toString', 'noSuchMethod', 'runtimeType', // From Iterable. 'isEmpty', 'isNotEmpty', 'length', 'any', 'contains', 'every', 'join', // From List. 'add', 'addAll', 'clear', 'fillRange', 'indexOf', 'insert', 'insertAll', 'lastIndexOf', 'remove', 'removeRange', 'replaceRange', 'setAll', 'setRange', 'shuffle', '[]=', // From JSArray. 'checkMutable', 'checkGrowable', ]); Set<String> doesNotEscapeMapSet = new Set<String>.from( const <String>[ // From Object. '==', 'hashCode', 'toString', 'noSuchMethod', 'runtimeType', // from Map. 'isEmpty', 'isNotEmpty', 'length', 'clear', 'containsKey', 'containsValue', '[]=', // [keys] only allows key values to escape, which we do not track. 'keys' ]); abstract class TracerVisitor<T extends TypeInformation> implements TypeInformationVisitor { final T tracedType; final TypeGraphInferrerEngine inferrer; final Compiler compiler; static const int MAX_ANALYSIS_COUNT = 16; final Setlet<Element> analyzedElements = new Setlet<Element>(); TracerVisitor(this.tracedType, TypeGraphInferrerEngine inferrer) : this.inferrer = inferrer, this.compiler = inferrer.compiler; // Work list that gets populated with [TypeInformation] that could // contain the container. final List<TypeInformation> workList = <TypeInformation>[]; // Work list of lists to analyze after analyzing the users of a // [TypeInformation]. We know the [tracedType] has been stored in these // lists and we must check how it escapes from these lists. final List<ListTypeInformation> listsToAnalyze = <ListTypeInformation>[]; // Work list of maps to analyze after analyzing the users of a // [TypeInformation]. We know the [tracedType] has been stored in these // maps and we must check how it escapes from these maps. final List<MapTypeInformation> mapsToAnalyze = <MapTypeInformation>[]; final Setlet<TypeInformation> flowsInto = new Setlet<TypeInformation>(); // The current [TypeInformation] in the analysis. TypeInformation currentUser; bool continueAnalyzing = true; void addNewEscapeInformation(TypeInformation info) { if (flowsInto.contains(info)) return; flowsInto.add(info); workList.add(info); } bool _wouldBeTooManyUsers(Set users) { int seenSoFar = analyzedElements.length; if (seenSoFar + users.length <= MAX_ANALYSIS_COUNT) return false; int actualWork = users .where((TypeInformation user) => !analyzedElements.contains(user.owner)) .length; return seenSoFar + actualWork > MAX_ANALYSIS_COUNT; } void analyze() { // Collect the [TypeInformation] where the list can flow in, // as well as the operations done on all these [TypeInformation]s. addNewEscapeInformation(tracedType); while (!workList.isEmpty) { currentUser = workList.removeLast(); if (_wouldBeTooManyUsers(currentUser.users)) { bailout('Too many users'); break; } for (TypeInformation info in currentUser.users) { analyzedElements.add(info.owner); info.accept(this); } while (!listsToAnalyze.isEmpty) { analyzeStoredIntoList(listsToAnalyze.removeLast()); } while (!mapsToAnalyze.isEmpty) { analyzeStoredIntoMap(mapsToAnalyze.removeLast()); } if (!continueAnalyzing) break; } } void bailout(String reason) { if (_VERBOSE) { print('Bailing out on $tracedType because: $reason'); } continueAnalyzing = false; } void visitAwaitTypeInformation(AwaitTypeInformation info) { bailout("Passed through await"); } void visitNarrowTypeInformation(NarrowTypeInformation info) { addNewEscapeInformation(info); } void visitPhiElementTypeInformation(PhiElementTypeInformation info) { addNewEscapeInformation(info); } void visitElementInContainerTypeInformation( ElementInContainerTypeInformation info) { addNewEscapeInformation(info); } void visitKeyInMapTypeInformation(KeyInMapTypeInformation info) { // We do not track the use of keys from a map, so we have to bail. bailout('Used as key in Map'); } void visitValueInMapTypeInformation(ValueInMapTypeInformation info) { addNewEscapeInformation(info); } void visitListTypeInformation(ListTypeInformation info) { listsToAnalyze.add(info); } void visitMapTypeInformation(MapTypeInformation info) { mapsToAnalyze.add(info); } void visitConcreteTypeInformation(ConcreteTypeInformation info) {} void visitStringLiteralTypeInformation(StringLiteralTypeInformation info) {} void visitClosureTypeInformation(ClosureTypeInformation info) {} void visitClosureCallSiteTypeInformation( ClosureCallSiteTypeInformation info) {} visitStaticCallSiteTypeInformation(StaticCallSiteTypeInformation info) { Element called = info.calledElement; if (inferrer.types.getInferredTypeOf(called) == currentUser) { addNewEscapeInformation(info); } } void analyzeStoredIntoList(ListTypeInformation list) { inferrer.analyzeListAndEnqueue(list); if (list.bailedOut) { bailout('Stored in a list that bailed out'); } else { list.flowsInto.forEach((flow) { flow.users.forEach((user) { if (user is !DynamicCallSiteTypeInformation) return; if (user.receiver != flow) return; if (inferrer._returnsListElementTypeSet.contains(user.selector)) { addNewEscapeInformation(user); } else if (!doesNotEscapeListSet.contains(user.selector.name)) { bailout('Escape from a list via [${user.selector.name}]'); } }); }); } } void analyzeStoredIntoMap(MapTypeInformation map) { inferrer.analyzeMapAndEnqueue(map); if (map.bailedOut) { bailout('Stored in a map that bailed out'); } else { map.flowsInto.forEach((flow) { flow.users.forEach((user) { if (user is !DynamicCallSiteTypeInformation) return; if (user.receiver != flow) return; if (user.selector.isIndex) { addNewEscapeInformation(user); } else if (!doesNotEscapeMapSet.contains(user.selector.name)) { bailout('Escape from a map via [${user.selector.name}]'); } }); }); } } /** * Checks whether this is a call to a list adding method. The definition * of what list adding means has to stay in sync with * [isParameterOfListAddingMethod]. */ bool isAddedToContainer(DynamicCallSiteTypeInformation info) { if (info.arguments == null) return false; var receiverType = info.receiver.type; if (!receiverType.isContainer) return false; String selectorName = info.selector.name; List<TypeInformation> arguments = info.arguments.positional; return (selectorName == '[]=' && currentUser == arguments[1]) || (selectorName == 'insert' && currentUser == arguments[1]) || (selectorName == 'add' && currentUser == arguments[0]); } bool isIndexSetOnMap(DynamicCallSiteTypeInformation info) { if (info.arguments == null) return false; var receiverType = info.receiver.type; if (!receiverType.isMap) return false; return info.selector.name == '[]='; } /** * Checks whether this is a call to a map adding method for values. The * definition of map adding method has to stay in sync with * [isParameterOfMapAddingMethod]. */ bool isValueAddedToMap(DynamicCallSiteTypeInformation info) { return isIndexSetOnMap(info) && currentUser == info.arguments.positional[1]; } /** * Checks whether this is a call to a map adding method for keys. The * definition of map adding method has to stay in sync with * [isParameterOfMapAddingMethod]. */ bool isKeyAddedToMap(DynamicCallSiteTypeInformation info) { return isIndexSetOnMap(info) && currentUser == info.arguments.positional[0]; } void visitDynamicCallSiteTypeInformation( DynamicCallSiteTypeInformation info) { if (isAddedToContainer(info)) { ContainerTypeMask mask = info.receiver.type; if (mask.allocationNode != null) { ListTypeInformation list = inferrer.types.allocatedLists[mask.allocationNode]; listsToAnalyze.add(list); } else { // The [ContainerTypeMask] is a union of two containers, and // we lose track of where these containers have been allocated // at this point. bailout('Stored in too many containers'); } } else if (isValueAddedToMap(info)) { MapTypeMask mask = info.receiver.type; if (mask.allocationNode != null) { MapTypeInformation map = inferrer.types.allocatedMaps[mask.allocationNode]; mapsToAnalyze.add(map); } else { // The [MapTypeMask] is a union. See comment for // [ContainerTypeMask] above. bailout('Stored in too many maps'); } } else if (isKeyAddedToMap(info)) { // We do not track the use of keys from a map, so we have to bail. bailout('Used as key in Map'); } if (info.targetsIncludeComplexNoSuchMethod(inferrer) && info.arguments != null && info.arguments.contains(currentUser)) { bailout('Passed to noSuchMethod'); } Iterable<Element> inferredTargetTypes = info.targets.map((element) { return inferrer.types.getInferredTypeOf(element); }); if (inferredTargetTypes.any((user) => user == currentUser)) { addNewEscapeInformation(info); } } /** * Check whether element is the parameter of a list adding method. * The definition of what a list adding method is has to stay in sync with * [isAddedToContainer]. */ bool isParameterOfListAddingMethod(Element element) { if (!element.isParameter) return false; if (element.enclosingClass != compiler.backend.listImplementation) { return false; } Element method = element.enclosingElement; return (method.name == '[]=') || (method.name == 'add') || (method.name == 'insert'); } /** * Check whether element is the parameter of a list adding method. * The definition of what a list adding method is has to stay in sync with * [isValueAddedToMap] and [isKeyAddedToMap]. */ bool isParameterOfMapAddingMethod(Element element) { if (!element.isParameter) return false; if (element.enclosingClass != compiler.backend.mapImplementation) { return false; } Element method = element.enclosingElement; return (method.name == '[]='); } bool isClosure(Element element) { if (!element.isFunction) return false; /// Creating an instance of a class that implements [Function] also /// closurizes the corresponding [call] member. We do not currently /// track these, thus the check for [isClosurized] on such a method will /// return false. Instead we catch that case here for now. // TODO(herhut): Handle creation of closures from instances of Function. if (element.isInstanceMember && element.name == Compiler.CALL_OPERATOR_NAME) { return true; } Element outermost = element.outermostEnclosingMemberOrTopLevel; return outermost.declaration != element.declaration; } void visitMemberTypeInformation(MemberTypeInformation info) { Element element = info.element; if (info.isClosurized) { bailout('Returned from a closurized method'); } if (isClosure(info.element)) { bailout('Returned from a closure'); } if (!inferrer.compiler.backend .canBeUsedForGlobalOptimizations(info.element)) { bailout('Escape to code that has special backend treatment'); } addNewEscapeInformation(info); } void visitParameterTypeInformation(ParameterTypeInformation info) { ParameterElement element = info.element; if (inferrer.isNativeElement(element.functionDeclaration)) { bailout('Passed to a native method'); } if (!inferrer.compiler.backend .canBeUsedForGlobalOptimizations(info.element)) { bailout('Escape to code that has special backend treatment'); } if (isParameterOfListAddingMethod(info.element) || isParameterOfMapAddingMethod(info.element)) { // These elements are being handled in // [visitDynamicCallSiteTypeInformation]. return; } addNewEscapeInformation(info); } }