dart2js cps: Store the TypeMask for each primitive in a field.

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 '../closure.dart' show
@@ skipping 22 matching lines @@
 import 'cps_ir_nodes_sexpr.dart' show SExpressionStringifier;
 
 /**
  * Replaces aggregates with a set of local values.  Performs inlining of
  * single-use closures to generate more replacable aggregates.
  */
 class ScalarReplacer extends Pass {
   String get passName => 'Scalar replacement';
 
   final dart2js.InternalErrorFunction _internalError;
+  final World _classWorld;
 
   ScalarReplacer(dart2js.Compiler compiler)
-      : _internalError = compiler.internalError;
+      : _internalError = compiler.internalError,
+        _classWorld = compiler.world;
 
   @override
   void rewrite(FunctionDefinition root) {
     // Set all parent pointers.
     new ParentVisitor().visit(root);
     ScalarReplacementVisitor analyzer =
-        new ScalarReplacementVisitor(_internalError);
+        new ScalarReplacementVisitor(_internalError, _classWorld);
     analyzer.analyze(root);
     analyzer.process();
   }
 }
 
 /**
  * Do scalar replacement of aggregates on instances. Since scalar replacement
  * can create new candidiates, iterate until all scalar replacements are done.
  */
 class ScalarReplacementVisitor extends RecursiveVisitor {
 
   final dart2js.InternalErrorFunction internalError;
+  final World classWorld;
   ScalarReplacementRemovalVisitor removalVisitor;
 
   Primitive _current = null;
   Set<Primitive> _allocations = new Set<Primitive>();
   Queue<Primitive> _queue = new Queue<Primitive>();
 
-  ScalarReplacementVisitor(this.internalError) {
+  ScalarReplacementVisitor(this.internalError, this.classWorld) {
     removalVisitor = new ScalarReplacementRemovalVisitor(this);
   }
 
   void analyze(FunctionDefinition root) {
     visit(root);
   }
 
   void process() {
     while (_queue.isNotEmpty) {
       Primitive allocation = _queue.removeFirst();
@@ skipping 41 matching lines @@
     }
 
     // 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 = insertAtBody(insertionPoint, let);
       }
       LetMutable let = new LetMutable(variable, initialValue);
       let.value.parent = let;
       insertionPoint = insertAtBody(insertionPoint, let);
     }
 
     // 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.substituteFor(getField);
           replacePrimitive(getField, getter);
           deletePrimitive(getField);
         } else {
           Primitive value = fieldInitialValues[getField.field];
           value.substituteFor(getField);
           deleteLetPrimOf(getField);
         }
       } else if (use is SetField && use.object == ref) {
         SetField setField = use;
         MutableVariable variable = cells[setField.field];
         Primitive value = setField.value.definition;
+        variable.type = variable.type.union(value.type, classWorld);
         SetMutable setter = new SetMutable(variable, value);
         setter.variable.parent = setter;
         setter.value.parent = setter;
         setter.substituteFor(setField);
         replacePrimitive(setField, setter);
         deletePrimitive(setField);
       } else {
         assert(false);
       }
     }
@@ skipping 64 matching lines @@
 class ScalarReplacementRemovalVisitor extends RecursiveVisitor {
   ScalarReplacementVisitor process;
 
   ScalarReplacementRemovalVisitor(this.process);
 
   processReference(Reference reference) {
     process.reconsider(reference.definition);
     reference.unlink();
   }
 }