<html><head><meta http-equiv="Content-Type" content="text/html charset=utf-8"></head><body style="word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space;" class=""><br class=""><div><blockquote type="cite" class=""><div class="">On Jul 22, 2016, at 2:35 PM, Adve, Vikram Sadanand <<a href="mailto:vadve@illinois.edu" class="">vadve@illinois.edu</a>> wrote:</div><br class="Apple-interchange-newline"><div class=""><div style="font-family: Helvetica; font-size: 12px; font-style: normal; font-variant-caps: normal; font-weight: normal; letter-spacing: normal; orphans: auto; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; widows: auto; word-spacing: 0px; -webkit-text-stroke-width: 0px;" class=""><blockquote type="cite" class=""><div class="">On Jul 22, 2016, at 4:31 PM, Mehdi Amini <<a href="mailto:mehdi.amini@apple.com" class="">mehdi.amini@apple.com</a>> wrote:</div><br class="Apple-interchange-newline"><div class=""><blockquote type="cite" class="" style="font-family: Calibri; font-size: 14px; font-style: normal; font-variant-ligatures: normal; font-variant-position: normal; font-variant-caps: normal; font-variant-numeric: normal; font-variant-alternates: normal; font-variant-east-asian: normal; font-weight: normal; letter-spacing: normal; orphans: auto; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; widows: auto; word-spacing: 0px; -webkit-text-stroke-width: 0px;"><div class=""><br class="Apple-interchange-newline">On Jul 22, 2016, at 12:36 PM, Teresa Johnson via llvm-dev <<a href="mailto:llvm-dev@lists.llvm.org" class="">llvm-dev@lists.llvm.org</a>> wrote:</div><br class="Apple-interchange-newline"><div class=""><div dir="ltr" class="">Hi Vikram,<div class=""><br class=""></div><div class="">Thanks!</div><div class=""><br class=""></div><div class="">I'm not sure what part got committed in the 3.8 timeframe - it looks like that was released back in March?</div></div></div></blockquote><div class="" style="font-family: Calibri; font-size: 14px; font-style: normal; font-variant-ligatures: normal; font-variant-position: normal; font-variant-caps: normal; font-variant-numeric: normal; font-variant-alternates: normal; font-variant-east-asian: normal; font-weight: normal; letter-spacing: normal; orphans: auto; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; widows: auto; word-spacing: 0px; -webkit-text-stroke-width: 0px;"><br class=""></div><div class="" style="font-family: Calibri; font-size: 14px; font-style: normal; font-variant-ligatures: normal; font-variant-position: normal; font-variant-caps: normal; font-variant-numeric: normal; font-variant-alternates: normal; font-variant-east-asian: normal; font-weight: normal; letter-spacing: normal; orphans: auto; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; widows: auto; word-spacing: 0px; -webkit-text-stroke-width: 0px;">3.8 was branched in early January though. </div><div class="" style="font-family: Calibri; font-size: 14px; font-style: normal; font-variant-ligatures: normal; font-variant-position: normal; font-variant-caps: normal; font-variant-numeric: normal; font-variant-alternates: normal; font-variant-east-asian: normal; font-weight: normal; letter-spacing: normal; orphans: auto; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; widows: auto; word-spacing: 0px; -webkit-text-stroke-width: 0px;">It has some of the work-in-progress for ThinLTO, it “could” work in simple cases I guess, but it hasn’t really been tested.</div><div class="" style="font-family: Calibri; font-size: 14px; font-style: normal; font-variant-ligatures: normal; font-variant-position: normal; font-variant-caps: normal; font-variant-numeric: normal; font-variant-alternates: normal; font-variant-east-asian: normal; font-weight: normal; letter-spacing: normal; orphans: auto; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; widows: auto; word-spacing: 0px; -webkit-text-stroke-width: 0px;">Also, in 3.8, the state was basically what was presented at EuroLLVM, while (as explained in the blog post), we ended up redesigning it significantly.</div></div></blockquote><div class=""><br class=""></div>OK. I’m not really trying to use 3.8.</div><div style="font-family: Helvetica; font-size: 12px; font-style: normal; font-variant-caps: normal; font-weight: normal; letter-spacing: normal; orphans: auto; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; widows: auto; word-spacing: 0px; -webkit-text-stroke-width: 0px;" class=""><br class=""></div><div style="font-family: Helvetica; font-size: 12px; font-style: normal; font-variant-caps: normal; font-weight: normal; letter-spacing: normal; orphans: auto; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; widows: auto; word-spacing: 0px; -webkit-text-stroke-width: 0px;" class=""><br class=""><blockquote type="cite" class=""><div class=""><div class="" style="font-family: Calibri; font-size: 14px; font-style: normal; font-variant-ligatures: normal; font-variant-position: normal; font-variant-caps: normal; font-variant-numeric: normal; font-variant-alternates: normal; font-variant-east-asian: normal; font-weight: normal; letter-spacing: normal; orphans: auto; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; widows: auto; word-spacing: 0px; -webkit-text-stroke-width: 0px;">In 3.9 we changed the bitcode format and broke backward compatibility: 3.9 won’t be able to read a ThinLTO bitcode generated by 3.8 (this is possible only because “ThinLTO was not supported in 3.8”). </div></div></blockquote><div class=""><br class=""></div><div class="">Since 3.9 isn’t quite out yet, is this also true for trunk, then? Thanks,</div></div></div></blockquote><div><br class=""></div><div>3.9 has been branched last week, so you can consider trunk “feature complete” for ThinLTO.</div><div><br class=""></div><div><br class=""></div><div>— </div><div>Mehdi</div><div><br class=""></div><br class=""><blockquote type="cite" class=""><div class=""><div style="font-family: Helvetica; font-size: 12px; font-style: normal; font-variant-caps: normal; font-weight: normal; letter-spacing: normal; orphans: auto; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; widows: auto; word-spacing: 0px; -webkit-text-stroke-width: 0px;" class=""><div class=""><br class=""></div><div class="">—Vikram</div><div class=""><br class=""></div><div class=""><br class=""></div><br class=""><blockquote type="cite" class=""><div class="" style="font-family: Calibri; font-size: 14px; font-style: normal; font-variant-ligatures: normal; font-variant-position: normal; font-variant-caps: normal; font-variant-numeric: normal; font-variant-alternates: normal; font-variant-east-asian: normal; font-weight: normal; letter-spacing: normal; orphans: auto; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; widows: auto; word-spacing: 0px; -webkit-text-stroke-width: 0px;">— </div><div class="" style="font-family: Calibri; font-size: 14px; font-style: normal; font-variant-ligatures: normal; font-variant-position: normal; font-variant-caps: normal; font-variant-numeric: normal; font-variant-alternates: normal; font-variant-east-asian: normal; font-weight: normal; letter-spacing: normal; orphans: auto; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; widows: auto; word-spacing: 0px; -webkit-text-stroke-width: 0px;">Mehdi</div><div class="" style="font-family: Calibri; font-size: 14px; font-style: normal; font-variant-ligatures: normal; font-variant-position: normal; font-variant-caps: normal; font-variant-numeric: normal; font-variant-alternates: normal; font-variant-east-asian: normal; font-weight: normal; letter-spacing: normal; orphans: auto; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; widows: auto; word-spacing: 0px; -webkit-text-stroke-width: 0px;"><br class=""></div><div class="" style="font-family: Calibri; font-size: 14px; font-style: normal; font-variant-ligatures: normal; font-variant-position: normal; font-variant-caps: normal; font-variant-numeric: normal; font-variant-alternates: normal; font-variant-east-asian: normal; font-weight: normal; letter-spacing: normal; orphans: auto; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; widows: auto; word-spacing: 0px; -webkit-text-stroke-width: 0px;"><br class=""></div><div class="" style="font-family: Calibri; font-size: 14px; font-style: normal; font-variant-ligatures: normal; font-variant-position: normal; font-variant-caps: normal; font-variant-numeric: normal; font-variant-alternates: normal; font-variant-east-asian: normal; font-weight: normal; letter-spacing: normal; orphans: auto; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; widows: auto; word-spacing: 0px; -webkit-text-stroke-width: 0px;"><br class=""></div><br class="" style="font-family: Calibri; font-size: 14px; font-style: normal; font-variant-ligatures: normal; font-variant-position: normal; font-variant-caps: normal; font-variant-numeric: normal; font-variant-alternates: normal; font-variant-east-asian: normal; font-weight: normal; letter-spacing: normal; orphans: auto; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; widows: auto; word-spacing: 0px; -webkit-text-stroke-width: 0px;"><blockquote type="cite" class="" style="font-family: Calibri; font-size: 14px; font-style: normal; font-variant-ligatures: normal; font-variant-position: normal; font-variant-caps: normal; font-variant-numeric: normal; font-variant-alternates: normal; font-variant-east-asian: normal; font-weight: normal; letter-spacing: normal; orphans: auto; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; widows: auto; word-spacing: 0px; -webkit-text-stroke-width: 0px;"><div class=""><div dir="ltr" class=""><div class="">A number of fixes have gone in since then so I would stick with a more recent version. The ThinLTO in trunk and (presumably 3.9 which seems to have not yet gone out?) is complete and working with multiple threads using gold. </div><div class=""><br class=""></div><div class="">The distributed build support is also in (which needs support in the build system however), although I am fixing a few bugs right now that popped up in testing our internal apps. Which distributed build system do you use? We have support coming out in Bazel, which is our open sourced distributed build system.</div><div class=""><br class=""></div><div class="">Let me know if you run into any issues or have any other questions!</div><div class=""><br class=""></div><div class="">Teresa</div><div class=""><br class=""></div></div><div class="gmail_extra"><br class=""><div class="gmail_quote">On Fri, Jul 22, 2016 at 12:15 PM, Adve, Vikram Sadanand via llvm-dev<span class="Apple-converted-space"> </span><span dir="ltr" class=""><<a href="mailto:llvm-dev@lists.llvm.org" target="_blank" class="">llvm-dev@lists.llvm.org</a>></span><span class="Apple-converted-space"> </span>wrote:<br class=""><blockquote class="gmail_quote" style="margin: 0px 0px 0px 0.8ex; border-left-width: 1px; border-left-color: rgb(204, 204, 204); border-left-style: solid; padding-left: 1ex;">First, kudos on the ThinLTO results reported in your blog post — they’re impressive and the system sounds really well engineered.<br class=""><br class="">I’m starting to try it out on a large piece of software and I’d like to make sure I know what to expect. The blog said it will be available in clang-3.9 but both clang-3.8 and trunk seem to have some degree of support for it. What is the status of ThinLTO in 3.8 (preferably) or trunk (otherwise)? Are either of these usable with multiple threads? What about for a distributed build?<br class=""><br class="">Thanks!<br class=""><br class="">-—Vikram<br class=""><br class="">// Vikram S. Adve<br class="">// Professor, Department of Computer Science<br class="">// University of Illinois at Urbana-Champaign<br class="">//<span class="Apple-converted-space"> </span><a href="mailto:vadve@illinois.edu" class="">vadve@illinois.edu</a><br class="">//<span class="Apple-converted-space"> </span><a href="https://urldefense.proofpoint.com/v2/url?u=http-3A__llvm.org_&d=CwMFaQ&c=8hUWFZcy2Z-Za5rBPlktOQ&r=b7uK7dJM4Fx7J_ehsuohEdD-6NdkoLyTwBFfHX-XKcc&m=JW9g_P9abYPtr9wIwNKwtHt0tcKqV8j_7oJ-7R7dd8U&s=K7WpW1rDZu2vzCM633oS96pOLLMpi6Tkn2wbIARNnBw&e=" rel="noreferrer" target="_blank" class="">http://llvm.org</a><br class=""><br class="">_______________________________________________<br class="">LLVM Developers mailing list<br class=""><a href="mailto:llvm-dev@lists.llvm.org" class="">llvm-dev@lists.llvm.org</a><br class=""><a href="https://urldefense.proofpoint.com/v2/url?u=http-3A__lists.llvm.org_cgi-2Dbin_mailman_listinfo_llvm-2Ddev&d=CwMFaQ&c=8hUWFZcy2Z-Za5rBPlktOQ&r=b7uK7dJM4Fx7J_ehsuohEdD-6NdkoLyTwBFfHX-XKcc&m=JW9g_P9abYPtr9wIwNKwtHt0tcKqV8j_7oJ-7R7dd8U&s=fVCeEw1e8BpO10e-LWWTewoeS34-RSbIj5CLt78ifY8&e=" rel="noreferrer" target="_blank" class="">http://lists.llvm.org/cgi-bin/mailman/listinfo/llvm-dev</a><br class=""></blockquote></div><br class=""><br clear="all" class=""><div class=""><br class=""></div>--<span class="Apple-converted-space"> </span><br class=""><div class="gmail_signature" data-smartmail="gmail_signature"><span class="" style="font-family: Times; font-size: inherit;"><table cellspacing="0" cellpadding="0" class=""><tbody class=""><tr class="" style="color: rgb(85, 85, 85); font-family: sans-serif; font-size: small;"><td nowrap="" class="" style="border-top-style: solid; border-top-color: rgb(213, 15, 37); border-top-width: 2px;">Teresa Johnson |</td><td nowrap="" class="" style="border-top-style: solid; border-top-color: rgb(51, 105, 232); border-top-width: 2px;"> Software Engineer |</td><td nowrap="" class="" style="border-top-style: solid; border-top-color: rgb(0, 153, 57); border-top-width: 2px;"> <a href="mailto:tejohnson@google.com" target="_blank" class="">tejohnson@google.com</a> |</td><td nowrap="" class="" style="border-top-style: solid; border-top-color: rgb(238, 178, 17); border-top-width: 2px;"> 408-460-2413</td></tr></tbody></table></span></div></div>_______________________________________________<br class="">LLVM Developers mailing list<br class=""><a href="mailto:llvm-dev@lists.llvm.org" class="">llvm-dev@lists.llvm.org</a><br class=""><a href="http://lists.llvm.org/cgi-bin/mailman/listinfo/llvm-dev" class="">http://lists.llvm.org/cgi-bin/mailman/listinfo/llvm-dev</a></div></blockquote></blockquote></div></div></blockquote></div><br class=""></body></html>