Revert "typed arrays: only share ArrayBuffer backing store"

We're going to fix this differently. The real bug is that
Buffer::HasInstance() returns true for typed arrays.

This reverts commit 01ee551e70.

src/v8_typed_array.cc

@@ -35,41 +35,11 @@ using node::ThrowRangeError;
 using node::ThrowTypeError;
 using node::ThrowError;
 
-template <unsigned int TBytes, v8::ExternalArrayType TEAType>
-class TypedArray;
-
-typedef TypedArray<1, v8::kExternalByteArray> Int8Array;
-typedef TypedArray<1, v8::kExternalUnsignedByteArray> Uint8Array;
-typedef TypedArray<1, v8::kExternalPixelArray> Uint8ClampedArray;
-typedef TypedArray<2, v8::kExternalShortArray> Int16Array;
-typedef TypedArray<2, v8::kExternalUnsignedShortArray> Uint16Array;
-typedef TypedArray<4, v8::kExternalIntArray> Int32Array;
-typedef TypedArray<4, v8::kExternalUnsignedIntArray> Uint32Array;
-typedef TypedArray<4, v8::kExternalFloatArray> Float32Array;
-typedef TypedArray<8, v8::kExternalDoubleArray> Float64Array;
-
 struct BatchedMethods {
   const char* name;
   v8::Handle<v8::Value> (*func)(const v8::Arguments& args);
 };
 
-void WeakCallback(v8::Persistent<v8::Value> value, void* data) {
-  v8::Object* obj = v8::Object::Cast(*value);
-
-  void* ptr = obj->GetIndexedPropertiesExternalArrayData();
-  int element_size = v8_typed_array::SizeOfArrayElementForType(
-      obj->GetIndexedPropertiesExternalArrayDataType());
-  int size =
-      obj->GetIndexedPropertiesExternalArrayDataLength() * element_size;
-
-  v8::V8::AdjustAmountOfExternalAllocatedMemory(-size);
-
-  value.ClearWeak();
-  value.Dispose();
-
-  free(ptr);
-}
-
 class ArrayBuffer {
  public:
   static v8::Persistent<v8::FunctionTemplate> GetTemplate() {
@@ -99,6 +69,23 @@ class ArrayBuffer {
   }
 
  private:
+  static void WeakCallback(v8::Persistent<v8::Value> value, void* data) {
+    v8::Object* obj = v8::Object::Cast(*value);
+
+    void* ptr = obj->GetIndexedPropertiesExternalArrayData();
+    int element_size = v8_typed_array::SizeOfArrayElementForType(
+        obj->GetIndexedPropertiesExternalArrayDataType());
+    int size =
+        obj->GetIndexedPropertiesExternalArrayDataLength() * element_size;
+
+    v8::V8::AdjustAmountOfExternalAllocatedMemory(-size);
+
+    value.ClearWeak();
+    value.Dispose();
+
+    free(ptr);
+  }
+
   static v8::Handle<v8::Value> V8New(const v8::Arguments& args) {
     if (!args.IsConstructCall())
       return ThrowTypeError("Constructor cannot be called as a function.");
@@ -138,7 +125,7 @@ class ArrayBuffer {
 
     v8::Persistent<v8::Object> persistent =
         v8::Persistent<v8::Object>::New(args.This());
-    persistent.MakeWeak(NULL, WeakCallback);
+    persistent.MakeWeak(NULL, &ArrayBuffer::WeakCallback);
 
     return args.This();
   }
@@ -264,23 +251,12 @@ class TypedArray {
     unsigned int length = 0;
     unsigned int byte_offset = 0;
 
-    if (node::Buffer::HasInstance(args[0]) ||
+    // [m1k3] added support for Buffer constructor
-        ArrayBuffer::HasInstance(args[0])) {
+    if (node::Buffer::HasInstance(args[0])
+        || ArrayBuffer::HasInstance(args[0])) {  // ArrayBuffer constructor.
       buffer = v8::Local<v8::Object>::Cast(args[0]);
-      size_t buflen = buffer->GetIndexedPropertiesExternalArrayDataLength();
+      size_t buflen =
-
+          buffer->GetIndexedPropertiesExternalArrayDataLength();
-      // Try to short-circuit as early as possible. Assume that in most
-      // `new TypedArray(other_array)` calls, the old and the new array
-      // have the same type.
-      bool make_copy = HasInstance(buffer) ||
-                       Int8Array::HasInstance(buffer) ||
-                       Uint8Array::HasInstance(buffer) ||
-                       Int16Array::HasInstance(buffer) ||
-                       Uint16Array::HasInstance(buffer) ||
-                       Int32Array::HasInstance(buffer) ||
-                       Uint32Array::HasInstance(buffer) ||
-                       Float32Array::HasInstance(buffer) ||
-                       Float64Array::HasInstance(buffer);
 
       if (!args[1]->IsUndefined() && args[1]->Int32Value() < 0)
         return ThrowRangeError("Byte offset out of range.");
@@ -305,23 +281,6 @@ class TypedArray {
       }
 
       void* buf = buffer->GetIndexedPropertiesExternalArrayData();
-
-      if (make_copy) {
-        void* dst = malloc(length);
-
-        if (dst == NULL)
-          return ThrowError("Out of memory.");
-
-        v8::V8::AdjustAmountOfExternalAllocatedMemory(length);
-        memcpy(dst, static_cast<const char*>(buf) + byte_offset, length);
-        v8::Persistent<v8::Object> persistent =
-            v8::Persistent<v8::Object>::New(args.This());
-        persistent->SetIndexedPropertiesToExternalArrayData(dst,
-                                                            TEAType,
-                                                            length);
-        persistent.MakeWeak(NULL, WeakCallback);
-      }
-      else {
       char* begin = reinterpret_cast<char*>(buf) + byte_offset;
 
       if (!checkAlignment(reinterpret_cast<uintptr_t>(begin), TBytes))
@@ -330,7 +289,6 @@ class TypedArray {
       args.This()->SetIndexedPropertiesToExternalArrayData(
         begin, TEAType, length);
     }
-    }
     else if (args[0]->IsObject()) {  // TypedArray / type[] constructor.
       v8::Local<v8::Object> obj = v8::Local<v8::Object>::Cast(args[0]);
       length = obj->Get(v8::String::New("length"))->Uint32Value();
@@ -503,6 +461,16 @@ class TypedArray {
   }
 };
 
+class Int8Array : public TypedArray<1, v8::kExternalByteArray> { };
+class Uint8Array : public TypedArray<1, v8::kExternalUnsignedByteArray> { };
+class Uint8ClampedArray : public TypedArray<1, v8::kExternalPixelArray> { };
+class Int16Array : public TypedArray<2, v8::kExternalShortArray> { };
+class Uint16Array : public TypedArray<2, v8::kExternalUnsignedShortArray> { };
+class Int32Array : public TypedArray<4, v8::kExternalIntArray> { };
+class Uint32Array : public TypedArray<4, v8::kExternalUnsignedIntArray> { };
+class Float32Array : public TypedArray<4, v8::kExternalFloatArray> { };
+class Float64Array : public TypedArray<8, v8::kExternalDoubleArray> { };
+
 template <typename T>
 v8::Handle<v8::Value> cTypeToValue(T) {
   return v8::Undefined();

test/simple/test-typed-arrays.js

@@ -201,36 +201,3 @@ assert.throws(function() {
   view.setUint16(0, 1);
   assert.equal(view.getUint16(0), 1);
 })();
-
-(function() {
-  // Backing store should not be shared.
-  var a = new Uint8Array(1);
-  var b = new Uint8Array(a);
-  a[0] = 0;
-  b[0] = 1;
-  assert.equal(a[0], 0);
-  assert.equal(b[0], 1);
-})();
-
-(function() {
-  // Backing store should not be shared.
-  var a = new Uint8Array(2);
-  var b = new Uint16Array(a);
-  a[0] = 0;
-  a[1] = 0;
-  b[0] = 257;
-  assert.equal(a[0], 0);
-  assert.equal(a[1], 0);
-  assert.equal(b[0], 257);
-})();
-
-(function() {
-  // Backing store should be shared.
-  var abuf = new ArrayBuffer(32);
-  var a = new Uint8Array(abuf);
-  var b = new Uint8Array(abuf);
-  a[0] = 0;
-  b[0] = 1;
-  assert.equal(a[0], 1);
-  assert.equal(b[0], 1);
-})();