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<dt>Revision</dt> <dd><a href="http://trac.webkit.org/projects/webkit/changeset/194542">194542</a></dd>
<dt>Author</dt> <dd>fpizlo@apple.com</dd>
<dt>Date</dt> <dd>2016-01-04 11:33:35 -0800 (Mon, 04 Jan 2016)</dd>
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<h3>Log Message</h3>
<pre>B3 patchpoints should allow requesting scratch registers
https://bugs.webkit.org/show_bug.cgi?id=152669
Reviewed by Benjamin Poulain.
Scratch registers are something that we often need in many patchpoint use cases. In LLVM's
patchpoints, we didn't have a good way to request scratch registers. So, our current FTL code
often does crazy scratch register allocation madness even when it would be better to just ask
the backend for some registers. This patch adds a mechanism for requesting scratch registers
in B3, and wires it all the way to all of our register allocation and liveness
infrastructure.