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            <b><a class="bz_bug_link 
          bz_status_NEW "
   title="NEW - New tests introduced in r188545 fail on 32 bit ARM"
   href="https://bugs.webkit.org/show_bug.cgi?id=148376#c17">Comment # 17</a>
              on <a class="bz_bug_link 
          bz_status_NEW "
   title="NEW - New tests introduced in r188545 fail on 32 bit ARM"
   href="https://bugs.webkit.org/show_bug.cgi?id=148376">bug 148376</a>
              from <span class="vcard"><a class="email" href="mailto:gskachkov&#64;gmail.com" title="GSkachkov &lt;gskachkov&#64;gmail.com&gt;"> <span class="fn">GSkachkov</span></a>
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        <pre>Comment on <span class=""><a href="attachment.cgi?id=261574&amp;action=diff" name="attach_261574" title="Patch">attachment 261574</a> <a href="attachment.cgi?id=261574&amp;action=edit" title="Patch">[details]</a></span>
Patch

View in context: <a href="https://bugs.webkit.org/attachment.cgi?id=261574&amp;action=review">https://bugs.webkit.org/attachment.cgi?id=261574&amp;action=review</a>

<span class="quote">&gt;&gt; Source/JavaScriptCore/dfg/DFGSpeculativeJIT.cpp:4660
&gt;&gt; +        DFG_TYPE_CHECK(thisValue.jsValueRegs(), node-&gt;child2(), SpecCell, m_jit.branchIfNotCell(thisValue.jsValueRegs()));
&gt; 
&gt; When would this ever not be a cell?</span >

At start child2 type is SpeculatedType SpecHeapTop  = 0x3bbfffff -&gt; after this line it converts to SpeculatedType SpecCell = 0x000fffff
Without this line this code raise ASSERT error in following module <a href="https://github.com/WebKit/webkit/blob/master/Source/JavaScriptCore/dfg/DFGAbstractInterpreterInlines.h#L120">https://github.com/WebKit/webkit/blob/master/Source/JavaScriptCore/dfg/DFGAbstractInterpreterInlines.h#L120</a>
and it says that it expect Cell but there was Top. 
In JSVALUE64 branch this type check is done by following statement SpeculateCellOperand thisValue(this, node-&gt;child2()); (4653)</pre>
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