Add alignment checks to typed_data views

runtime/lib/typed_data.dart

Index: runtime/lib/typed_data.dart
diff --git a/runtime/lib/typed_data.dart b/runtime/lib/typed_data.dart
index e60c1459d560d8fa0179812755741de54faaae5a..c0b523b648f5cc37af5d3b801b0826afaec3437c 100644
--- a/runtime/lib/typed_data.dart
+++ b/runtime/lib/typed_data.dart
@@ -2181,6 +2181,7 @@ class _Int8ArrayView extends _TypedListView implements Int8List {
     _rangeCheck(buffer.lengthInBytes,
                 _offsetInBytes,
                 length * Int8List.BYTES_PER_ELEMENT);
+    _offsetAlignmentCheck(_offsetInBytes, Int8List.BYTES_PER_ELEMENT);

[siva, 2013/08/29 16:30:16]

int8, uint8 and uint8 clamped do not need any alignment checks
(BYTES_PER_ELEMENT is 1).

[Cutch, 2013/09/08 13:16:36]

Done.

   }
 
 
@@ -2232,6 +2233,7 @@ class _Uint8ArrayView extends _TypedListView implements Uint8List {
     _rangeCheck(buffer.lengthInBytes,
                 _offsetInBytes,
                 length * Uint8List.BYTES_PER_ELEMENT);
+    _offsetAlignmentCheck(_offsetInBytes, Uint8List.BYTES_PER_ELEMENT);

[siva, 2013/08/29 16:30:16]

see comment above.

[Cutch, 2013/09/08 13:16:36]

Done.

   }
 
 
@@ -2284,6 +2286,7 @@ class _Uint8ClampedArrayView extends _TypedListView implements Uint8ClampedList
     _rangeCheck(buffer.lengthInBytes,
                 offsetInBytes,
                 length * Uint8List.BYTES_PER_ELEMENT);
+    _offsetAlignmentCheck(_offsetInBytes, Uint8List.BYTES_PER_ELEMENT);

[siva, 2013/08/29 16:30:16]

Ditto.

[Cutch, 2013/09/08 13:16:36]

Done.

   }
 
 
@@ -2335,6 +2338,7 @@ class _Int16ArrayView extends _TypedListView implements Int16List {
     _rangeCheck(buffer.lengthInBytes,
                 offsetInBytes,
                 length * Int16List.BYTES_PER_ELEMENT);
+    _offsetAlignmentCheck(_offsetInBytes, Int16List.BYTES_PER_ELEMENT);
   }
 
 
@@ -2386,6 +2390,7 @@ class _Uint16ArrayView extends _TypedListView implements Uint16List {
     _rangeCheck(buffer.lengthInBytes,
                 offsetInBytes,
                 length * Uint16List.BYTES_PER_ELEMENT);
+    _offsetAlignmentCheck(_offsetInBytes, Uint16List.BYTES_PER_ELEMENT);
   }
 
 
@@ -2437,6 +2442,7 @@ class _Int32ArrayView extends _TypedListView implements Int32List {
     _rangeCheck(buffer.lengthInBytes,
                 offsetInBytes,
                 length * Int32List.BYTES_PER_ELEMENT);
+    _offsetAlignmentCheck(_offsetInBytes, Int32List.BYTES_PER_ELEMENT);
   }
 
 
@@ -2488,6 +2494,7 @@ class _Uint32ArrayView extends _TypedListView implements Uint32List {
     _rangeCheck(buffer.lengthInBytes,
                 offsetInBytes,
                 length * Uint32List.BYTES_PER_ELEMENT);
+    _offsetAlignmentCheck(_offsetInBytes, Uint32List.BYTES_PER_ELEMENT);
   }
 
 
@@ -2539,6 +2546,7 @@ class _Int64ArrayView extends _TypedListView implements Int64List {
     _rangeCheck(buffer.lengthInBytes,
                 offsetInBytes,
                 length * Int64List.BYTES_PER_ELEMENT);
+    _offsetAlignmentCheck(_offsetInBytes, Int64List.BYTES_PER_ELEMENT);
   }
 
 
@@ -2590,6 +2598,7 @@ class _Uint64ArrayView extends _TypedListView implements Uint64List {
     _rangeCheck(buffer.lengthInBytes,
                 offsetInBytes,
                 length * Uint64List.BYTES_PER_ELEMENT);
+    _offsetAlignmentCheck(_offsetInBytes, Uint64List.BYTES_PER_ELEMENT);
   }
 
 
@@ -2641,6 +2650,7 @@ class _Float32ArrayView extends _TypedListView implements Float32List {
     _rangeCheck(buffer.lengthInBytes,
                 offsetInBytes,
                 length * Float32List.BYTES_PER_ELEMENT);
+    _offsetAlignmentCheck(_offsetInBytes, Float32List.BYTES_PER_ELEMENT);
   }
 
 
@@ -2692,6 +2702,7 @@ class _Float64ArrayView extends _TypedListView implements Float64List {
     _rangeCheck(buffer.lengthInBytes,
                 offsetInBytes,
                 length * Float64List.BYTES_PER_ELEMENT);
+    _offsetAlignmentCheck(_offsetInBytes, Float64List.BYTES_PER_ELEMENT);
   }
 
 
@@ -2743,6 +2754,7 @@ class _Float32x4ArrayView extends _TypedListView implements Float32x4List {
     _rangeCheck(buffer.lengthInBytes,
                 offsetInBytes,
                 length * Float32x4List.BYTES_PER_ELEMENT);
+    _offsetAlignmentCheck(_offsetInBytes, Float32x4List.BYTES_PER_ELEMENT);
   }
 
 
@@ -3135,6 +3147,14 @@ void _rangeCheck(int listLength, int start, int length) {
 }
 
 
+void _offsetAlignmentCheck(int offset, int alignment) {
+  if ((offset % alignment) != 0) {
+    throw new RangeError('Offset ($offset) must be a multiple of '
+                         'BYTES_PER_ELEMENT ($alignment)');
+  }
+}
+
+
 int _defaultIfNull(object, value) {
   if (object == null) {
     return value;