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<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D">Thanks for the replies Mark, Michael and Filip.<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D">To follow up:<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D">Michael asks –“</span>What processor(s) and OS(es) are you targeting?”<o:p></o:p></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D">We are developing on game consoles, our focus is on the ps4 and xboxone. The cpu’s are
</span><span style="font-size:9.5pt;font-family:Consolas;color:black;background:white;mso-highlight:white">X86_64</span><span style="font-size:9.5pt;font-family:Consolas;color:black">,
</span><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D">and their OS are ‘similar’ to unix/windows.<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D">Mark wrote – “</span>the C LOOP LLINT emulated a CPU’s behavior using emitted C instructions. As a result, it incurs a performance penalty that is under 10%
(vs the ASM LLINT) if I remember correctly”<span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D"><o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D">A potential 10% savings is something we’re interested in, we really do want it to perform as well as it can within the limitations are working with (no JIT).
We gave it a quick try since it appeared easy to do but encountered some build problems. We have decided to try again once we re-integrate the recent changes from webkit into our codebase. This will probably be quite some time from now, so I’ll pick it up
again then.<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D">Thanks again for the help<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D">Chris
<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D"><o:p> </o:p></span></p>
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<p class="MsoNormal"><b><span style="font-size:11.0pt;font-family:"Calibri","sans-serif"">From:</span></b><span style="font-size:11.0pt;font-family:"Calibri","sans-serif""> Mark Lam [mailto:mark.lam@apple.com]
<br>
<b>Sent:</b> Friday, September 05, 2014 4:14 PM<br>
<b>To:</b> Vienneau, Christopher<br>
<b>Cc:</b> webkit-dev@lists.webkit.org<br>
<b>Subject:</b> Re: [webkit-dev] Using OfflineAsm<o:p></o:p></span></p>
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<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal">On Sep 5, 2014, at 4:05 PM, Mark Lam <<a href="mailto:mark.lam@apple.com">mark.lam@apple.com</a>> wrote:<o:p></o:p></p>
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<p class="MsoNormal" style="text-indent:-.25in"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif"">4)</span><span style="font-size:7.0pt"> <span class="apple-converted-space"> </span></span><span style="font-size:11.0pt;font-family:"Calibri","sans-serif"">Should
I actually expect a performance increase compared to the “C LOOP”?<o:p></o:p></span></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal">Yes. The ASM LLINT should be faster than the C LOOP LLINT.<o:p></o:p></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal">To clarify, the C LOOP LLINT emulated a CPU’s behavior using emitted C instructions. As a result, it incurs a performance penalty that is under 10% (vs the ASM LLINT) if I remember correctly. So, the perf gain you’ll get comes from recuperating
the losses due to the C loop being a CPU emulator. You should not expect to see any of the more substantive gains that come from the JITs.<o:p></o:p></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal">Regards,<o:p></o:p></p>
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<p class="MsoNormal">Mark<o:p></o:p></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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