dart2js cps: Replace GetLazyStatic with GetStatic.

pkg/compiler/lib/src/cps_ir/cps_ir_nodes.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.
 library dart2js.ir_nodes;
 
 import 'dart:collection';
 import '../constants/values.dart' as values;
 import '../dart_types.dart' show DartType, InterfaceType, TypeVariableType;
 import '../elements/elements.dart';
 import '../io/source_information.dart' show SourceInformation;
@@ skipping 1287 matching lines @@
 
   void setParentPointers() {
     object.parent = this;
     index.parent = this;
     value.parent = this;
   }
 }
 
 /// Reads the value of a static field or tears off a static method.
 ///
-/// Note that lazily initialized fields should be read using GetLazyStatic.
+/// If [GetStatic] is used to load a lazily initialized static field, it must
+/// have been initialized beforehand, and a [witness] must be set to restrict
+/// code motion.
 class GetStatic extends Primitive {
   /// Can be [FieldElement] or [FunctionElement].
   final Element element;
   final SourceInformation sourceInformation;
 
+  /// If reading a lazily initialized field, [witness] must refer to a node
+  /// that initializes the field or always occurs after the field initializer.
+  ///
+  /// The value of the witness is not used.
+  Reference<Primitive> witness;
+
   GetStatic(this.element, [this.sourceInformation]);
 
+  /// Read a lazily initialized static field that is known to have been
+  /// initialized by [witness] or earlier.
+  GetStatic.witnessed(this.element, Primitive witness, [this.sourceInformation])
+      : witness = witness == null ? null : new Reference<Primitive>(witness);
+
   accept(Visitor visitor) => visitor.visitGetStatic(this);
 
   bool get hasValue => true;
   bool get isSafeForElimination => true;
   bool get isSafeForReordering {
     return element is FunctionElement || element.isFinal;
   }
 
-  void setParentPointers() {}
+  void setParentPointers() {
+    if (witness != null) {
+      witness.parent = this;
+    }
+  }
 }
 
 /// Sets the value of a static field.
 class SetStatic extends Primitive {
   final FieldElement element;
   final Reference<Primitive> value;
   final SourceInformation sourceInformation;
 
   SetStatic(this.element, Primitive value, [this.sourceInformation])
       : this.value = new Reference<Primitive>(value);
@@ skipping 766 matching lines @@
 
   processGetField(GetField node) {}
   visitGetField(GetField node) {
     processGetField(node);
     processReference(node.object);
   }
 
   processGetStatic(GetStatic node) {}
   visitGetStatic(GetStatic node) {
     processGetStatic(node);
+    if (node.witness != null) {
+      processReference(node.witness);
+    }
   }
 
   processSetStatic(SetStatic node) {}
   visitSetStatic(SetStatic node) {
     processSetStatic(node);
     processReference(node.value);
   }
 
   processCreateBox(CreateBox node) {}
   visitCreateBox(CreateBox node) {
@@ skipping 233 matching lines @@
 /// Visit a just-deleted subterm and unlink all [Reference]s in it.
 class RemovalVisitor extends TrampolineRecursiveVisitor {
   processReference(Reference reference) {
     reference.unlink();
   }
 
   static void remove(Node node) {
     (new RemovalVisitor()).visit(node);
   }
 }