dart2js cps: Use definitions by default, not references.

pkg/compiler/lib/src/cps_ir/scalar_replacement.dart

 // Copyright (c) 2015, 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.cps_ir.scalar_replacement;
 
 import 'optimizers.dart';
 
 import 'dart:collection' show Queue;
 
 import '../common.dart';
@@ skipping 59 matching lines @@
     }
   }
 
   void tryScalarReplacement(Primitive allocation) {
 
     // We can do scalar replacement of an aggregate if all uses of an allocation
     // are reads or writes.
     for (Reference ref = allocation.firstRef; ref != null; ref = ref.next) {
       Node use = ref.parent;
       if (use is GetField) continue;
-      if (use is SetField && use.object == ref) continue;
+      if (use is SetField && use.objectRef == ref) continue;
       return;
     }
 
     Set<FieldElement> reads = new Set<FieldElement>();
     Set<FieldElement> writes = new Set<FieldElement>();
     for (Reference ref = allocation.firstRef; ref != null; ref = ref.next) {
       Node use = ref.parent;
       if (use is GetField) {
         reads.add(use.field);
       } else if (use is SetField) {
         writes.add(use.field);
       } else {
         assert(false);
       }
     }
 
     // Find the initial values of the fields. A CreateBox has no initial
     // values. CreateInstance has initial values in the order of the fields.
     Map<FieldElement, Primitive> fieldInitialValues =
         <FieldElement, Primitive>{};
     if (allocation is CreateInstance) {
       int i = 0;
       allocation.classElement.forEachInstanceField(
         (ClassElement enclosingClass, FieldElement field) {
-          Primitive argument = allocation.arguments[i++].definition;
+          Primitive argument = allocation.argument(i++);
           fieldInitialValues[field] = argument;
         },
         includeSuperAndInjectedMembers: true);
     }
 
     // Create [MutableVariable]s for each written field. Initialize the
     // MutableVariable with the value from the allocator, or initialize with a
     // `null` constant if there is not initial value.
     Map<FieldElement, MutableVariable> cells =
         <FieldElement, MutableVariable>{};
     InteriorNode insertionPoint = allocation.parent;  // LetPrim
     for (FieldElement field in writes) {
       MutableVariable variable = new MutableVariable(field);
       variable.type = new TypeMask.nonNullEmpty();
       cells[field] = variable;
       Primitive initialValue = fieldInitialValues[field];
       if (initialValue == null) {
         assert(allocation is CreateBox);
         initialValue = new Constant(new NullConstantValue());
         LetPrim let = new LetPrim(initialValue);
         let.primitive.parent = let;
         insertionPoint = let..insertBelow(insertionPoint);
       }
       LetMutable let = new LetMutable(variable, initialValue);
-      let.value.parent = let;
+      let.valueRef.parent = let;
       insertionPoint = let..insertBelow(insertionPoint);
     }
 
     // Replace references with MutableVariable operations or references to the
     // field's value.
     for (Reference ref = allocation.firstRef; ref != null; ref = ref.next) {
       Node use = ref.parent;
       if (use is GetField) {
         GetField getField = use;
         MutableVariable variable = cells[getField.field];
         if (variable != null) {
           GetMutable getter = new GetMutable(variable);
           getter.type = getField.type;
-          getter.variable.parent = getter;
+          getter.variableRef.parent = getter;
           getField.replaceUsesWith(getter);
           replacePrimitive(getField, getter);
           deletePrimitive(getField);
         } else {
           Primitive value = fieldInitialValues[getField.field];
           getField.replaceUsesWith(value);
           deleteLetPrimOf(getField);
         }
-      } else if (use is SetField && use.object == ref) {
+      } else if (use is SetField && use.objectRef == ref) {
         SetField setField = use;
         MutableVariable variable = cells[setField.field];
-        Primitive value = setField.value.definition;
+        Primitive value = setField.value;
         variable.type = variable.type.union(value.type, classWorld);
         SetMutable setter = new SetMutable(variable, value);
-        setter.variable.parent = setter;
-        setter.value.parent = setter;
+        setter.variableRef.parent = setter;
+        setter.valueRef.parent = setter;
         setField.replaceUsesWith(setter);
         replacePrimitive(setField, setter);
         deletePrimitive(setField);
       } else {
         assert(false);
       }
     }
 
     // Delete [allocation] since that might 'free' another scalar replacement
     // candidate by deleting the last non-field-access.
@@ skipping 49 matching lines @@
 class ScalarReplacementRemovalVisitor extends TrampolineRecursiveVisitor {
   ScalarReplacementVisitor process;
 
   ScalarReplacementRemovalVisitor(this.process);
 
   processReference(Reference reference) {
     process.reconsider(reference.definition);
     reference.unlink();
   }
 }