Trace static tear-off closures.

sdk/lib/_internal/compiler/implementation/inferrer/closure_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;
 
 class ClosureTracerVisitor extends TracerVisitor {
-  ClosureTracerVisitor(tracedType, inferrer) : super(tracedType, inferrer);
+  final Element tracedElement;
+
+  ClosureTracerVisitor(this.tracedElement, tracedType, inferrer)
+      : super(tracedType, inferrer);
 
   void run() {
-    ClosureTypeInformation closure = tracedType;
-    FunctionElement element = closure.element;
-    element.functionSignature.forEachParameter((Element parameter) {
+    tracedElement.functionSignature.forEachParameter((Element parameter) {
       ElementTypeInformation info = inferrer.types.getInferredTypeOf(parameter);
       info.abandonInferencing = false;
     });
     analyze();
-    element.functionSignature.forEachParameter((Element parameter) {
+    tracedElement.functionSignature.forEachParameter((Element parameter) {
       ElementTypeInformation info = inferrer.types.getInferredTypeOf(parameter);
       if (continueAnalyzing) {
         info.disableHandleSpecialCases = true;
       } else {
         info.giveUp(inferrer);
       }
     });
   }
 
   visitMapTypeInformation(MapTypeInformation info) {
     bailout('Stored in a map');
   }
 
   void analyzeCall(CallSiteTypeInformation info) {
-    ClosureTypeInformation closure = tracedType;
-    FunctionElement element = closure.element;
     Selector selector = info.selector;
-    if (!selector.signatureApplies(element, compiler)) return;
+    if (!selector.signatureApplies(tracedElement, compiler)) return;
     inferrer.updateParameterAssignments(
-        info, element, info.arguments, selector, remove: false,
+        info, tracedElement, info.arguments, selector, remove: false,
         addToQueue: false);
   }
 
   visitClosureCallSiteTypeInformation(ClosureCallSiteTypeInformation info) {
     super.visitClosureCallSiteTypeInformation(info);
     if (info.closure == currentUser) {
       analyzeCall(info);
     } else {
       bailout('Passed to a closure');
     }
   }
 
   visitStaticCallSiteTypeInformation(StaticCallSiteTypeInformation info) {
     super.visitStaticCallSiteTypeInformation(info);
     Element called = info.calledElement;
-    if (called.isForeign(compiler) && called.name == 'JS') {
-      bailout('Used in JS ${info.call}');
+    if (called.isForeign(compiler)) {
+      String name = called.name;
+      if (name == 'JS' || name == 'DART_CLOSURE_TO_JS') {
+        bailout('Used in JS ${info.call}');
+      }
     }
-    if (inferrer.types.getInferredTypeOf(called) == currentUser) {
+    if (called.isGetter()
+        && info.selector != null
+        && info.selector.isCall()
+        && inferrer.types.getInferredTypeOf(called) == currentUser) {
       // This node can be a closure call as well. For example, `foo()`
       // where `foo` is a getter.
       analyzeCall(info);
     }
   }
 
   bool checkIfCurrentUser(element) {
     return inferrer.types.getInferredTypeOf(element) == currentUser;
   }
 
   visitDynamicCallSiteTypeInformation(DynamicCallSiteTypeInformation info) {
     super.visitDynamicCallSiteTypeInformation(info);
     if (info.selector.isCall()) {
       if (info.arguments.contains(currentUser)
           && !info.targets.every((element) => element.isFunction())) {
         bailout('Passed to a closure');
       } else if (info.targets.any((element) => checkIfCurrentUser(element))) {
         analyzeCall(info);
       }
     }
   }
 }
+
+class StaticTearOffClosureTracerVisitor extends ClosureTracerVisitor {
+  StaticTearOffClosureTracerVisitor(tracedElement, tracedType, inferrer)
+      : super(tracedElement, tracedType, inferrer);
+
+  visitStaticCallSiteTypeInformation(StaticCallSiteTypeInformation info) {
+    super.visitStaticCallSiteTypeInformation(info);
+    if (info.calledElement == tracedElement
+        && info.selector != null
+        && info.selector.isGetter()) {
+      addNewEscapeInformation(info);
+    }
+  }
+}