Change List constructors.

sdk/lib/_internal/compiler/implementation/ssa/optimize.dart

 // Copyright (c) 2012, 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 ssa;
 
 abstract class OptimizationPhase {
   String get name;
   void visitGraph(HGraph graph);
 }
@@ skipping 201 matching lines @@
       return node.inputs[1];
     }
     return node;
   }
 
   bool isFixedSizeListConstructor(HInvokeStatic node) {
     Element element = node.target.element;
     DartType defaultClass = compiler.listClass.defaultClass;
     // TODO(ngeoffray): make sure that the only reason the List class is
     // not resolved is because it's not being used.
-    return element.isConstructor()
-        && defaultClass != null
-        && element.enclosingElement.declaration == defaultClass.element
-        && node.inputs.length == 2
-        && node.inputs[1].isInteger(types);
+    if (defaultClass == null) return false;
+    if (!element.isConstructor()) return false;
+    // TODO(ngeoffray): cache constructor.
+    if (element.enclosingElement.declaration != defaultClass.element) {
+      return false;
+    }
+    FunctionElement fixedLengthListConstructor =
+        compiler.listClass.lookupConstructor(
+            new Selector.callConstructor(const SourceString("fixedLength"),
+                                         compiler.listClass.getLibrary()));
+    return element == fixedLengthListConstructor.defaultImplementation;
   }
 
   HInstruction visitInvokeStatic(HInvokeStatic node) {
     if (isFixedSizeListConstructor(node)) {
       node.guaranteedType = HType.FIXED_ARRAY;
     }
     return node;
   }
 
   HInstruction visitInvokeDynamic(HInvokeDynamic node) {
@@ skipping 315 matching lines @@
     if (!receiverType.isUseful()) return null;
     if (receiverType.canBeNull()) return null;
     DartType type = receiverType.computeType(compiler);
     if (type == null) return null;
     return compiler.world.locateSingleField(type, selector);
   }
 
   HInstruction visitFieldGet(HFieldGet node) {
     if (node.element == backend.jsArrayLength) {
       if (node.receiver is HInvokeStatic) {
-        // Try to recognize the length getter with input [:new List(int):].
+        // Try to recognize the length getter with input [:new List.fixedLength(int):].
         HInvokeStatic call = node.receiver;
         if (isFixedSizeListConstructor(call)) {
           return call.inputs[1];
         }
       }
     }
     return node;
   }
 
   HInstruction optimizeLengthInterceptedCall(HInvokeDynamicGetter node) {
@@ skipping 785 matching lines @@
     }
 
     // For other fields having setters in the generative constructor body, set
     // the type to UNKNOWN to avoid relying on the type set in the initializer
     // list.
     allSetters.forEach((Element element) {
       backend.registerFieldConstructor(element, HType.UNKNOWN);
     });
   }
 }