<html>
<head>
<base href="https://bugs.webkit.org/" />
</head>
<body><table border="1" cellspacing="0" cellpadding="8">
<tr>
<th>Bug ID</th>
<td><a class="bz_bug_link
bz_status_NEW "
title="NEW - Factoring out baseline code generation for JS operations into snippet generators"
href="https://bugs.webkit.org/show_bug.cgi?id=149600">149600</a>
</td>
</tr>
<tr>
<th>Summary</th>
<td>Factoring out baseline code generation for JS operations into snippet generators
</td>
</tr>
<tr>
<th>Classification</th>
<td>Unclassified
</td>
</tr>
<tr>
<th>Product</th>
<td>WebKit
</td>
</tr>
<tr>
<th>Version</th>
<td>WebKit Local Build
</td>
</tr>
<tr>
<th>Hardware</th>
<td>Unspecified
</td>
</tr>
<tr>
<th>OS</th>
<td>Unspecified
</td>
</tr>
<tr>
<th>Status</th>
<td>NEW
</td>
</tr>
<tr>
<th>Severity</th>
<td>Normal
</td>
</tr>
<tr>
<th>Priority</th>
<td>P2
</td>
</tr>
<tr>
<th>Component</th>
<td>JavaScriptCore
</td>
</tr>
<tr>
<th>Assignee</th>
<td>webkit-unassigned@lists.webkit.org
</td>
</tr>
<tr>
<th>Reporter</th>
<td>mark.lam@apple.com
</td>
</tr></table>
<p>
<div>
<pre>Currently, a lot of DFG and FTL code generation for JS operations only handles operands that are of a primitive type like int32 and double. This is the case even when type profiling predicts that the operands will be of a non-number or polymorphic type. If the operand is not an int32 or double, the generated DFG/FTL code will currently OSR exit to the baseline JIT. In contrast, the baseline JIT does have code to handle all types of operands (either via generated code or via a call to a C++ runtime helper). We should factor out the baseline code that handles these polymorphic operands into re-targettable snippet generators, and allow the DFG and FTL to use them to generate code to handle polymorphic operands when the type profiling data calls for it. This will prevent OSR exits due to operations on polymorphic operands when they can be predicted.</pre>
</div>
</p>
<hr>
<span>You are receiving this mail because:</span>
<ul>
<li>You are the assignee for the bug.</li>
</ul>
</body>
</html>