Redo "Use TypedArray.set for setRange of between similarly typed lists implemented as TypedArrays"

sdk/lib/typed_data/dart2js/typed_data_dart2js.dart

Index: sdk/lib/typed_data/dart2js/typed_data_dart2js.dart
diff --git a/sdk/lib/typed_data/dart2js/typed_data_dart2js.dart b/sdk/lib/typed_data/dart2js/typed_data_dart2js.dart
index 6a4e0f1ac7b129a5cf8a71924881e398e5435efc..f91472af77c2c05631253d0e58392fb15280e737 100644
--- a/sdk/lib/typed_data/dart2js/typed_data_dart2js.dart
+++ b/sdk/lib/typed_data/dart2js/typed_data_dart2js.dart
@@ -456,16 +456,78 @@ class ByteData extends TypedData native "DataView" {
       JS('ByteData', 'new DataView(#, #, #)', arg1, arg2, arg3);
 }
 
+
+// TODO(sra): Move this type to a public name in a private library so that other
+// platform libraries like dart:html and dart:webaudio can tell a native array
+// from a list that implements the implicit interface.
+abstract class _NativeTypedArray extends TypedData
+    implements JavaScriptIndexingBehavior {
+  int get length => JS("JSUInt32", '#.length', this);
+
+  bool _setRangeFast(int start, int end,
+      _NativeTypedArray source, int skipCount) {
+    int targetLength = this.length;
+    _checkIndex(start, targetLength + 1);
+    _checkIndex(end, targetLength + 1);
+    if (start > end) throw new RangeError.range(start, 0, end);
+    int count = end - start;
+
+    if (skipCount < 0) throw new ArgumentError(skipCount);
+
+    int sourceLength = source.length;
+    if (sourceLength - skipCount < count)  {
+      throw new StateError("Not enough elements");
+    }
+
+    if (skipCount != 0 || sourceLength != count) {
+      // Create a view of the exact subrange that is copied from the source.
+      source = JS('', '#.subarray(#, #)',
+          source, skipCount, skipCount + count);
+    }
+    JS('void', '#.set(#, #)', this, source, start);
+  }
+}
+
+// TODO(sra): Move to private library, like [_NativeTypedArray].
+abstract class _NativeTypedArrayOfDouble
+    extends _NativeTypedArray
+        with ListMixin<double>, FixedLengthListMixin<double>
+    implements List<double> {
+
+  void setRange(int start, int end, Iterable<double> iterable,
+                [int skipCount = 0]) {
+    if (iterable is _NativeTypedArrayOfDouble) {
+      _setRangeFast(start, end, iterable, skipCount);
+      return;
+    }
+    super.setRange(start, end, iterable, skipCount);
+  }
+}
+
+// TODO(sra): Move to private library, like [_NativeTypedArray].
+abstract class _NativeTypedArrayOfInt
+    extends _NativeTypedArray
+        with ListMixin<int>, FixedLengthListMixin<int>
+    implements List<int> {
+
+  void setRange(int start, int end, Iterable<int> iterable,
+                [int skipCount = 0]) {
+    if (iterable is _NativeTypedArrayOfInt) {
+      _setRangeFast(start, end, iterable, skipCount);
+      return;
+    }
+    super.setRange(start, end, iterable, skipCount);
+  }
+}
+
+
 /**
  * A fixed-length list of IEEE 754 single-precision binary floating-point
  * numbers  that is viewable as a [TypedData]. For long lists, this
  * implementation can be considerably more space- and time-efficient than
  * the default [List] implementation.
  */
-class Float32List
-    extends TypedData with ListMixin<double>, FixedLengthListMixin<double>
-    implements JavaScriptIndexingBehavior, List<double>
-    native "Float32Array" {
+class Float32List extends _NativeTypedArrayOfDouble native "Float32Array" {
   /**
    * Creates a [Float32List] of the specified length (in elements), all of
    * whose elements are initially zero.
@@ -502,8 +564,6 @@ class Float32List
 
   static const int BYTES_PER_ELEMENT = 4;
 
-  int get length => JS("JSUInt32", '#.length', this);
-
   num operator[](int index) {
     _checkIndex(index, length);
     return JS("num", "#[#]", this, index);
@@ -537,10 +597,7 @@ class Float32List
  * implementation can be considerably more space- and time-efficient than
  * the default [List] implementation.
  */
-class Float64List
-    extends TypedData with ListMixin<double>, FixedLengthListMixin<double>
-    implements JavaScriptIndexingBehavior, List<double>
-    native "Float64Array" {
+class Float64List extends _NativeTypedArrayOfDouble native "Float64Array" {
   /**
    * Creates a [Float64List] of the specified length (in elements), all of
    * whose elements are initially zero.
@@ -577,8 +634,6 @@ class Float64List
 
   static const int BYTES_PER_ELEMENT = 8;
 
-  int get length => JS("JSUInt32", '#.length', this);
-
   num operator[](int index) {
     _checkIndex(index, length);
     return JS("num", "#[#]", this, index);
@@ -614,10 +669,7 @@ class Float64List
  * [TypedData]. For long lists, this implementation can be considerably
  * more space- and time-efficient than the default [List] implementation.
  */
-class Int16List
-    extends TypedData with ListMixin<int>, FixedLengthListMixin<int>
-    implements JavaScriptIndexingBehavior, List<int>
-    native "Int16Array" {
+class Int16List extends _NativeTypedArrayOfInt native "Int16Array" {
   /**
    * Creates an [Int16List] of the specified length (in elements), all of
    * whose elements are initially zero.
@@ -653,8 +705,6 @@ class Int16List
 
   static const int BYTES_PER_ELEMENT = 2;
 
-  int get length => JS("JSUInt32", '#.length', this);
-
   int operator[](int index) {
     _checkIndex(index, length);
     return JS("int", "#[#]", this, index);
@@ -687,10 +737,7 @@ class Int16List
  * [TypedData]. For long lists, this implementation can be considerably
  * more space- and time-efficient than the default [List] implementation.
  */
-class Int32List
-    extends TypedData with ListMixin<int>, FixedLengthListMixin<int>
-    implements JavaScriptIndexingBehavior, List<int>
-    native "Int32Array" {
+class Int32List extends _NativeTypedArrayOfInt native "Int32Array" {
   /**
    * Creates an [Int32List] of the specified length (in elements), all of
    * whose elements are initially zero.
@@ -726,8 +773,6 @@ class Int32List
 
   static const int BYTES_PER_ELEMENT = 4;
 
-  int get length => JS("JSUInt32", '#.length', this);
-
   int operator[](int index) {
     _checkIndex(index, length);
     return JS("int", "#[#]", this, index);
@@ -760,10 +805,7 @@ class Int32List
  * For long lists, this implementation can be considerably
  * more space- and time-efficient than the default [List] implementation.
  */
-class Int8List
-    extends TypedData with ListMixin<int>, FixedLengthListMixin<int>
-    implements JavaScriptIndexingBehavior, List<int>
-    native "Int8Array" {
+class Int8List extends _NativeTypedArrayOfInt native "Int8Array" {
   /**
    * Creates an [Int8List] of the specified length (in elements), all of
    * whose elements are initially zero.
@@ -796,8 +838,6 @@ class Int8List
 
   static const int BYTES_PER_ELEMENT = 1;
 
-  int get length => JS("JSUInt32", '#.length', this);
-
   int operator[](int index) {
     _checkIndex(index, length);
     return JS("int", "#[#]", this, index);
@@ -830,10 +870,7 @@ class Int8List
  * [TypedData]. For long lists, this implementation can be considerably
  * more space- and time-efficient than the default [List] implementation.
  */
-class Uint16List
-    extends TypedData with ListMixin<int>, FixedLengthListMixin<int>
-    implements JavaScriptIndexingBehavior, List<int>
-    native "Uint16Array" {
+class Uint16List extends _NativeTypedArrayOfInt native "Uint16Array" {
   /**
    * Creates a [Uint16List] of the specified length (in elements), all
    * of whose elements are initially zero.
@@ -870,8 +907,6 @@ class Uint16List
 
   static const int BYTES_PER_ELEMENT = 2;
 
-  int get length => JS("JSUInt32", '#.length', this);
-
   int operator[](int index) {
     _checkIndex(index, length);
     return JS("JSUInt31", "#[#]", this, index);
@@ -904,10 +939,7 @@ class Uint16List
  * [TypedData]. For long lists, this implementation can be considerably
  * more space- and time-efficient than the default [List] implementation.
  */
-class Uint32List
-    extends TypedData with ListMixin<int>, FixedLengthListMixin<int>
-    implements JavaScriptIndexingBehavior, List<int>
-    native "Uint32Array" {
+class Uint32List extends _NativeTypedArrayOfInt native "Uint32Array" {
   /**
    * Creates a [Uint32List] of the specified length (in elements), all
    * of whose elements are initially zero.
@@ -944,8 +976,6 @@ class Uint32List
 
   static const int BYTES_PER_ELEMENT = 4;
 
-  int get length => JS("JSUInt32", '#.length', this);
-
   int operator[](int index) {
     _checkIndex(index, length);
     return JS("JSUInt32", "#[#]", this, index);
@@ -979,8 +1009,7 @@ class Uint32List
  * more space- and time-efficient than the default [List] implementation.
  * Indexed store clamps the value to range 0..0xFF.
  */
-class Uint8ClampedList extends TypedData with ListMixin<int>,
-    FixedLengthListMixin<int> implements JavaScriptIndexingBehavior, List<int>
+class Uint8ClampedList extends _NativeTypedArrayOfInt
     native "Uint8ClampedArray,CanvasPixelArray" {
   /**
    * Creates a [Uint8ClampedList] of the specified length (in elements), all of
@@ -1050,9 +1079,7 @@ class Uint8ClampedList extends TypedData with ListMixin<int>,
  * For long lists, this implementation can be considerably
  * more space- and time-efficient than the default [List] implementation.
  */
-class Uint8List
-    extends TypedData with ListMixin<int>, FixedLengthListMixin<int>
-    implements JavaScriptIndexingBehavior, List<int>
+class Uint8List extends _NativeTypedArrayOfInt
     // On some browsers Uint8ClampedArray is a subtype of Uint8Array.  Marking
     // Uint8List as !nonleaf ensures that the native dispatch correctly handles
     // the potential for Uint8ClampedArray to 'accidentally' pick up the
@@ -1125,7 +1152,9 @@ class Uint8List
  * [TypedData]. For long lists, this implementation can be considerably
  * more space- and time-efficient than the default [List] implementation.
  */
-class Int64List extends TypedData implements JavaScriptIndexingBehavior, List<int> {
+class Int64List
+    extends TypedData
+    implements JavaScriptIndexingBehavior, List<int> {
   /**
    * Creates an [Int64List] of the specified length (in elements), all of
    * whose elements are initially zero.
@@ -1170,7 +1199,9 @@ class Int64List extends TypedData implements JavaScriptIndexingBehavior, List<in
  * [TypedData]. For long lists, this implementation can be considerably
  * more space- and time-efficient than the default [List] implementation.
  */
-class Uint64List extends TypedData implements JavaScriptIndexingBehavior, List<int> {
+class Uint64List
+    extends TypedData
+    implements JavaScriptIndexingBehavior, List<int> {
   /**
    * Creates a [Uint64List] of the specified length (in elements), all
    * of whose elements are initially zero.