Copy ArrayBuffers at serialization time

See #936 (comment)

Author: domenic

source

@@ -2901,8 +2901,9 @@ a.setAttribute('href', 'https://example.com/'); // change the content attribute
 
      <li>The <dfn data-x-href="https://tc39.github.io/ecma262/#sec-arraycreate">ArrayCreate</dfn> abstract operation</li>
      <li>The <dfn data-x-href="https://tc39.github.io/ecma262/#sec-call">Call</dfn> abstract operation</li>
-     <li>The <dfn data-x-href="https://tc39.github.io/ecma262/#sec-clonearraybuffer">CloneArrayBuffer</dfn> abstract operation</li>
      <li>The <dfn data-x-href="https://tc39.github.io/ecma262/#sec-construct">Construct</dfn> abstract operation</li>
+     <li>The <dfn data-x-href="https://tc39.github.io/ecma262/#sec-copydatablockbytes">CopyDataBlockBytes</dfn> abstract operation</li>
+     <li>The <dfn data-x-href="https://tc39.github.io/ecma262/#sec-createbytedatablock">CreateByteDataBlock</dfn> abstract operation</li>
      <li>The <dfn data-x-href="https://tc39.github.io/ecma262/#sec-createdataproperty">CreateDataProperty</dfn> abstract operation</li>
      <li>The <dfn data-x-href="https://tc39.github.io/ecma262/#sec-detacharraybuffer">DetachArrayBuffer</dfn> abstract operation</li>
      <li>The <dfn data-x="js-EnqueueJob" data-x-href="https://tc39.github.io/ecma262/#sec-enqueuejob">EnqueueJob</dfn> abstract operation</li>
@@ -7885,9 +7886,20 @@ interface <dfn>DOMStringList</dfn> {
      <li><p>If <span>IsDetachedBuffer</span>(<var>value</var>) is true, then throw a
      <span>"<code>DataCloneError</code>"</span> <code>DOMException</code>.</p></li>
 
+     <li><p>Let <var>size</var> be <var>value</var>.[[ArrayBufferByteLength]].</p></li>
+
+     <li>
+      <p>Let <var>dataCopy</var> be ? <span>CreateByteDataBlock</span>(<var>size</var>).</p>
+
+      <p class="note">This can throw a <code data-x="js-RangeError">RangeError</code> exception upon
+      allocation failure.</p>
+     </li>
+
+     <li><p>Perform ! <span>CopyDataBlockBytes</span>(<var>dataCopy</var>, 0,
+     <var>value</var>.[[ArrayBufferData]], 0, <var>size</var>).</p></li>
+
      <li><p>Set <var>serialized</var> to { [[Type]]: "ArrayBuffer", [[ArrayBufferData]]:
-     <var>value</var>.[[ArrayBufferData]], [[ArrayBufferByteLength]]:
-     <var>value</var>.[[ArrayBufferByteLength]] }.</p></li>
+     <var>dataCopy</var>, [[ArrayBufferByteLength]]: <var>size</var> }.</p></li>
     </ol>
    </li>
 
@@ -8663,7 +8675,7 @@ interface <dfn>DOMStringList</dfn> {
      <li><p>Let <var>outputArrayBuffer</var> be the <span>%ArrayBuffer%</span> intrinsic object in
      <var>targetRealm</var>.
 
-     <li><p>Let <var>output</var> be ? <span>CloneArrayBuffer</span>(<var>input</var>, 0,
+     <li><p>Let <var>output</var> be ? CloneArrayBuffer(<var>input</var>, 0,
      <var>outputArrayBuffer</var>).</p></li>
     </ol>
    </li>