<div dir="ltr">If you think it's useful I can make the code unconditional w.r.t. NaCl, and make sahf/lahf the only thing generated here. I don't think performance is a real argument here, though, since this code path shouldn't get exercised often. If we really cared about performance then we wouldn't hit this path in the first place!</div><div class="gmail_extra"><br><div class="gmail_quote">On Fri, Dec 12, 2014 at 10:33 AM, Reid Kleckner <span dir="ltr"><<a href="mailto:rnk@google.com" target="_blank">rnk@google.com</a>></span> wrote:<br><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex">LLVM should never, ever generate popf from normal code. It's ridiculously slow. We should use sahf/lahf if we can.<br>
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