<div dir="ltr"><br><div class="gmail_extra"><br><div class="gmail_quote">On Tue, Mar 17, 2015 at 2:38 PM, Nicolas Cellier <span dir="ltr"><<a href="mailto:nicolas.cellier.aka.nice@gmail.com" target="_blank">nicolas.cellier.aka.nice@gmail.com</a>></span> wrote:<br><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex"> <br><div dir="ltr"><div><div><div><div><div><div><div><div><br></div>Hi again,<br></div>I've noticed the COG code currently branches on objectMemory wordSize = 8 condition,<br></div>to either load self positive64BitValueOf: integerArgument.<br></div>or to load self positive32BitValueOf: integerArgument.<br><br></div>Of course, this could be resolved to a single<br> integerArgument := self positiveMachineIntegerValueOf: integerArgument<br>which will care of the branch by itself...<br></div><div>That's what I did.<br></div><div><br></div>But maybe the intention was rather to deal with signed64BitValueOf in the 64 bit branch like what was done to primitiveBitShift?<br></div></div></div></blockquote><div><br></div><div>Right. I want to avoid the call altogether in that case.</div><div><br></div><div><br></div><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex"><div dir="ltr"><div><div>Of course, all this is assuming that the machine uses a 2-complement implementation, otherwise it won't match the Smalltalk semantic.<br>That's not so rare ;) - but theoretically not fully portable - contrarily to actual strategy which is fully portable.<br></div><div>Since other parts of the VM also rely on such specific, maybe we can trade a little portability tribute for the sake of speed.<br></div></div></div></blockquote><div><br></div><div>Yes, for me trying to make the VM portable to non-2's compliment systems isn't worth it. I remember that there's a fair bit of code in HPS that tries to cope with systems that don't have 8-bit bytes. Again pointless. The world is more homogenous now than it was in the time of PDP-10s, and that's a good thing. If some feature isn't exercised it atrophies and becomes a hindrance. </div><div><br></div><div> </div><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex"><div dir="ltr"><div><div></div><div><br>Thoughts?</div></div></div></blockquote><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex"><div dir="ltr"><div><div></div><br></div>Nicolas<br></div>
<br></blockquote></div><br><br clear="all"><div><br></div>-- <br><div>best,<div>Eliot</div></div>
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