<div dir="ltr">Oooh. Neat. Thanks Dave. Please go ahead and commit that.<div><br></div><div>Arnaud - I have no idea whether Dave's patch will help with this bug, but it's certainly worth testing.</div><div><br></div><div>- Lang.</div></div><div class="gmail_extra"><br><div class="gmail_quote">On Wed, Sep 10, 2014 at 4:10 PM, David Blaikie <span dir="ltr"><<a href="mailto:dblaikie@gmail.com" target="_blank">dblaikie@gmail.com</a>></span> wrote:<br><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex"><div dir="ltr">While I'm not sure where the leak is, using some pre-canned memory management might help... <br><br>Attached is a patch that changes this allocation to use shared_ptr, perhaps it'll address the bug?<br><br>(ideally we shouldn't need the intrusive ref counting (std::enable_shared_from_this) but instead have a weak_set that has std::weak_ptr in it & implicitly removes elements as they become null (probably on a harvesting schedule, rather than with a direct callback as is currently implemented))<br><div class="gmail_chip gmail_drive_chip" style="width:396px;min-height:18px;max-height:18px;background-color:#f5f5f5;padding:5px;color:#222;font-family:arial;font-style:normal;font-weight:bold;font-size:13px;border:1px solid #ddd;line-height:1"><a href="https://docs.google.com/file/d/0B0jpkch3iC_7TXFVU2hCcUpfZXM/edit?usp=drive_web" style="display:inline-block;overflow:hidden;text-overflow:ellipsis;white-space:nowrap;text-decoration:none;padding:1px 0px;border:none;width:100%" target="_blank"><img style="vertical-align:bottom;border:none" src="https://ssl.gstatic.com/docs/doclist/images/icon_10_generic_list.png"> <span dir="ltr" style="color:#15c;text-decoration:none;vertical-align:bottom">pbqp_leak.diff</span></a></div></div><div class="gmail_extra"><br><div class="gmail_quote">On Wed, Sep 10, 2014 at 3:19 PM, Arnaud A. de Grandmaison <span dir="ltr"><<a href="mailto:arnaud.degrandmaison@arm.com" target="_blank">arnaud.degrandmaison@arm.com</a>></span> wrote:<br><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex"><div lang="EN-GB" link="blue" vlink="purple"><div><p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1f497d">Hi Lang,<u></u><u></u></span></p><p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1f497d"><u></u> <u></u></span></p><p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1f497d">In PBQPBuilderWithCoalescing::build, around line 360, we have code looking like:<u></u><u></u></span></p><p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1f497d"><u></u> <u></u></span></p><p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1f497d">…<u></u><u></u></span></p><p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1f497d">PBQP::Vector newCosts(g.getNodeCosts(node));<u></u><u></u></span></p><p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1f497d">addPhysRegCoalesce(newCosts, pregOpt, cBenefit);<u></u><u></u></span></p><p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1f497d">g.setNodeCosts(node, newCosts);<u></u><u></u></span></p><p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1f497d">…<u></u><u></u></span></p><p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1f497d"><u></u> <u></u></span></p><p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1f497d">I suspect the leak occurs around the setNodeCosts method, and I have trouble understanding how it handles the case where the node already has costs.<u></u><u></u></span></p><p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1f497d"><u></u> <u></u></span></p><p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1f497d">It seems to me that:<u></u><u></u></span></p><p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1f497d"> - we make of copy of the node’s costs (probably because someone else can refer to it ?)<u></u><u></u></span></p><p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1f497d"> - we modify the copy<u></u><u></u></span></p><p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1f497d"> - we set the node’s new costs. But what is supposed to happen there, especially in the CostAllocator part ?<u></u><u></u></span></p><p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1f497d"><u></u> <u></u></span></p><p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1f497d">Could you shed some light there ?<u></u><u></u></span></p><p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1f497d"><u></u> <u></u></span></p><p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1f497d">Thanks,<u></u><u></u></span></p><p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1f497d">Arnaud<u></u><u></u></span></p><p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1f497d"><u></u> <u></u></span></p><p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1f497d"><u></u> <u></u></span></p><p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1f497d"><u></u> <u></u></span></p><p class="MsoNormal" style="margin-left:36.0pt"><b><span lang="EN-US" style="font-size:10.0pt;font-family:"Tahoma","sans-serif"">From:</span></b><span lang="EN-US" style="font-size:10.0pt;font-family:"Tahoma","sans-serif""> Lang Hames [mailto:<a href="mailto:lhames@gmail.com" target="_blank">lhames@gmail.com</a>] <br><b>Sent:</b> 10 September 2014 19:26<br><b>To:</b> Arnaud De Grandmaison<br><b>Subject:</b> Re: Leaks in PBQPBuilderWithCoalescing::build ?<u></u><u></u></span></p><p class="MsoNormal" style="margin-left:36.0pt"><u></u> <u></u></p><div><p class="MsoNormal" style="margin-left:36.0pt">Thanks Arnaud!<u></u><u></u></p><div><p class="MsoNormal" style="margin-left:36.0pt"><u></u> <u></u></p></div><div><p class="MsoNormal" style="margin-left:36.0pt">- Lang.<u></u><u></u></p></div></div><div><p class="MsoNormal" style="margin-left:36.0pt"><u></u> <u></u></p><div><p class="MsoNormal" style="margin-left:36.0pt">On Wed, Sep 10, 2014 at 11:23 AM, Arnaud A. de Grandmaison <<a href="mailto:arnaud.degrandmaison@arm.com" target="_blank">arnaud.degrandmaison@arm.com</a>> wrote:<u></u><u></u></p><div><div><p class="MsoNormal" style="margin-left:36.0pt">Hi Lang,<u></u><u></u></p><p class="MsoNormal" style="margin-left:36.0pt"> <u></u><u></u></p><p class="MsoNormal" style="margin-left:36.0pt">For your information, the leak sanitizer found something when I committed my patch:<u></u><u></u></p><p class="MsoNormal" style="margin-left:36.0pt"> <u></u><u></u></p><p class="MsoNormal" style="margin-left:36.0pt"><a href="http://lab.llvm.org:8011/builders/sanitizer-x86_64-linux-bootstrap/builds/4506/steps/check-llvm%20asan/logs/stdio" target="_blank">http://lab.llvm.org:8011/builders/sanitizer-x86_64-linux-bootstrap/builds/4506/steps/check-llvm%20asan/logs/stdio</a><u></u><u></u></p><p class="MsoNormal" style="margin-left:36.0pt"> <u></u><u></u></p><p class="MsoNormal" style="margin-left:36.0pt">I will try to have a look at it.<u></u><u></u></p><p class="MsoNormal" style="margin-left:36.0pt"> <u></u><u></u></p><p class="MsoNormal" style="margin-left:36.0pt">Cheers,<u></u><u></u></p><p class="MsoNormal" style="margin-left:36.0pt">--<u></u><u></u></p><p class="MsoNormal" style="margin-left:36.0pt">Arnaud A. de Grandmaison<u></u><u></u></p><p class="MsoNormal" style="margin-left:36.0pt"> <u></u><u></u></p></div></div></div><p class="MsoNormal" style="margin-left:36.0pt"><u></u> <u></u></p></div></div></div><br>_______________________________________________<br>
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