<div class="gmail_quote">On Tue, Jul 31, 2012 at 7:37 AM, Bertram Felgenhauer <span dir="ltr"><<a href="mailto:bertram.felgenhauer@googlemail.com" target="_blank">bertram.felgenhauer@googlemail.com</a>></span> wrote:<br>
<blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex"><div>Note that MVar# itself cannot be unpacked -- the StgMVar record will</div>
always be a separate heap object.</blockquote><div><br></div><div>One could imagine a couple of techniques to unpack the MVar# itself, and was curious if GHC might employ one of them.</div><div><br></div><div>So, really, unpacking the MVar does not eliminate a layer of indirection, it just eliminates the need to check a pointer tag (and possibly execute a thunk or follow some redirects if you don't have a pointer to an MVar#). I think this is what I was ultimately after.</div>
<div><br></div><div>Best,<br>Leon</div><div><br></div><div><br></div>
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