Menu
▾
▴
[X10-issues] [JIRA] (XTENLANG-3500) NativeX10: poor performance of arraty indexing in loop in Lulesh
|
From: David G. (JIRA) <ji...@xt...> - 2015-03-30 20:24:36
|
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd"> <html xmlns="http://www.w3.org/1999/xhtml"> <head> <meta http-equiv="Content-Type" content="text/html; charset=utf-8" /> <meta name="viewport" content="width=device-width, initial-scale=1.0, maximum-scale=1.0" /> <base href="https://xtenlang.atlassian.net" /> <title>Message Title</title> </head> <body class="jira" style="color: #333; font-family: Arial, sans-serif; font-size: 14px; line-height: 1.429"> <table id="background-table" cellpadding="0" cellspacing="0" width="100%" style="border-collapse: collapse; mso-table-lspace: 0pt; mso-table-rspace: 0pt; background-color: #f5f5f5; border-collapse: collapse; mso-table-lspace: 0pt; mso-table-rspace: 0pt"> <!-- header here --> <tr> <td id="header-pattern-container" style="padding: 0px; border-collapse: collapse; padding: 10px 20px"> <table id="header-pattern" cellspacing="0" cellpadding="0" border="0" style="border-collapse: collapse; mso-table-lspace: 0pt; mso-table-rspace: 0pt"> <tr> <td id="header-avatar-image-container" valign="top" style="padding: 0px; border-collapse: collapse; vertical-align: top; width: 32px; padding-right: 8px"> <img id="header-avatar-image" class="image_fix" src="cid:jira-generated-image-avatar-dgrove-07d59f44-1e0a-466d-bc17-0eb2a549b8e4" height="32" width="32" border="0" style="border-radius: 3px; vertical-align: top" /> </td> <td id="header-text-container" valign="middle" style="padding: 0px; border-collapse: collapse; vertical-align: middle; font-family: Arial, sans-serif; font-size: 14px; line-height: 20px; mso-line-height-rule: exactly; mso-text-raise: 1px"> <a class="user-hover" rel="dgrove" id="email_dgrove" href="https://xtenlang.atlassian.net/secure/ViewProfile.jspa?name=dgrove" style="color:#3b73af;; color: #3b73af; text-decoration: none">David Grove</a> <strong>updated</strong> an issue </td> </tr> </table> </td> </tr> <tr> <td id="email-content-container" style="padding: 0px; border-collapse: collapse; padding: 0 20px"> <table id="email-content-table" cellspacing="0" cellpadding="0" border="0" width="100%" style="border-collapse: collapse; mso-table-lspace: 0pt; mso-table-rspace: 0pt; border-spacing: 0; border-collapse: separate"> <tr> <!-- there needs to be content in the cell for it to render in some clients --> <td class="email-content-rounded-top mobile-expand" style="padding: 0px; border-collapse: collapse; color: #fff; padding: 0 15px 0 16px; height: 15px; background-color: #fff; border-left: 1px solid #ccc; border-top: 1px solid #ccc; border-right: 1px solid #ccc; border-bottom: 0; border-top-right-radius: 5px; border-top-left-radius: 5px; height: 10px; line-height: 10px; padding: 0 15px 0 16px; mso-line-height-rule: exactly"> </td> </tr> <tr> <td class="email-content-main mobile-expand " style="padding: 0px; border-collapse: collapse; border-left: 1px solid #ccc; border-right: 1px solid #ccc; border-top: 0; border-bottom: 0; padding: 0 15px 0 16px; background-color: #fff"> <table class="page-title-pattern" cellspacing="0" cellpadding="0" border="0" width="100%" style="border-collapse: collapse; mso-table-lspace: 0pt; mso-table-rspace: 0pt"> <tr> <td class="page-title-pattern-first-line " style="padding: 0px; border-collapse: collapse; font-family: Arial, sans-serif; font-size: 14px; padding-top: 10px"> <a href="https://xtenlang.atlassian.net/browse/XTENLANG" style="color: #3b73af; text-decoration: none">X10</a> / <a href="https://xtenlang.atlassian.net/browse/XTENLANG-3500" style="color: #3b73af; text-decoration: none"><img src="cid:jira-generated-image-static-bug-b93d6e83-961b-410d-b375-62557bddc63d" height="16" width="16" border="0" align="absmiddle" alt="Bug" style="vertical-align: text-bottom" /></a> <a href="https://xtenlang.atlassian.net/browse/XTENLANG-3500" style="color: #3b73af; text-decoration: none">XTENLANG-3500</a> </td> </tr> <tr> <td style="vertical-align: top;; padding: 0px; border-collapse: collapse; padding-right: 5px; font-size: 20px; line-height: 30px; mso-line-height-rule: exactly" class="page-title-pattern-header-container"> <span class="page-title-pattern-header" style="font-family: Arial, sans-serif; padding: 0; font-size: 20px; line-height: 30px; mso-text-raise: 2px; mso-line-height-rule: exactly; vertical-align: middle"> <a href="https://xtenlang.atlassian.net/browse/XTENLANG-3500" style="color: #3b73af; text-decoration: none">NativeX10: poor performance of arraty indexing in loop in Lulesh</a> </span> </td> </tr> </table> </td> </tr> <tr> <td class="email-content-main mobile-expand wrapper-special-margin" style="padding: 0px; border-collapse: collapse; border-left: 1px solid #ccc; border-right: 1px solid #ccc; border-top: 0; border-bottom: 0; padding: 0 15px 0 16px; background-color: #fff; padding-top: 10px; padding-bottom: 5px"> <table class="keyvalue-table" style="border-collapse: collapse; mso-table-lspace: 0pt; mso-table-rspace: 0pt"> <tr> <th style="color: #707070; font: normal 14px/20px Arial, sans-serif; text-align: left; vertical-align: top; padding: 2px 0"> Change By: </th> <td style="padding: 0px; border-collapse: collapse; font: normal 14px/20px Arial, sans-serif; padding: 2px 0 2px 5px; vertical-align: top"> <a class="user-hover" rel="dgrove" id="email_dgrove" href="https://xtenlang.atlassian.net/secure/ViewProfile.jspa?name=dgrove" style="color:#3b73af;; color: #3b73af; text-decoration: none">David Grove</a> </td> </tr> </table> </td> </tr> <tr> <td class="email-content-main mobile-expand issue-description-container" style="padding: 0px; border-collapse: collapse; border-left: 1px solid #ccc; border-right: 1px solid #ccc; border-top: 0; border-bottom: 0; padding: 0 15px 0 16px; background-color: #fff; padding-top: 5px; padding-bottom: 10px"> <table class="text-paragraph-pattern" cellspacing="0" cellpadding="0" border="0" width="100%" style="border-collapse: collapse; mso-table-lspace: 0pt; mso-table-rspace: 0pt; font-family: Arial, sans-serif; font-size: 14px; line-height: 20px; mso-line-height-rule: exactly; mso-text-raise: 2px"> <tr> <td class="text-paragraph-pattern-container mobile-resize-text " style="padding: 0px; border-collapse: collapse; padding: 0 0 10px 0"> <span class="diffcontext">Note from Josh: <br /><br />I just discovered a nasty 'anti-pattern' for our compiler. This code is around line 796 of Lulesh.x10 (it's also part of the kernel code I'm using to test foreach):<br /><br />{quote} <br /> for (i2 in min_i..max_i) {<br /> val i3 = 8*i2;<br /> val volinv = 1.0 / determ(i2);<br /> for (i1 in 0..3) {<br /> val i3f = i3;<br /> val hourmod = (a8n:Rail[Double]) => {<br /> a8n(i3f) * gamma(i1,0) + a8n(i3f+1) * gamma(i1,1) +<br /> a8n(i3f+2) * gamma(i1,2) + a8n(i3f+3) * gamma(i1,3) +<br /> a8n(i3f+4) * gamma(i1,4) + a8n(i3f+5) * gamma(i1,5) +<br /> a8n(i3f+6) * gamma(i1,6) + a8n(i3f+7) * gamma(i1,7)<br /> };<br /> ...<br /> }<br /> }<br />{quote}<br /><br />From perf report, I see an enormous set of integer instructions for array indexing inside the closure. I think this is happening because g++ is trying to be clever with our generated code and allocating separate stack variables for each of (i3+1, i3+2, i3+3, ...).<br /><br />The following hack eliminates most of the addq instructions, improving the performance of the kernel by about 25%:<br /><br />{</span> <span class="diffremovedchars" style="background-color: #ffe7e7; text-decoration:line-through;">{</span> <span class="diffaddedchars" style="background-color:#ddfade;">quote}</span> <span class="diffcontext"> var i3:Long = 8*min_i;<br /> for (i2 in min_i..max_i) {<br /> val volinv = 1.0 / determ(i2);<br /> for (i1 in 0..3) {<br /> val i3f = i3;<br /> val hourmod = (a8n:Rail[Double]) => {<br /> a8n(i3f) * gamma(i1,0) + a8n(i3f+1) * gamma(i1,1) +<br /> a8n(i3f+2) * gamma(i1,2) + a8n(i3f+3) * gamma(i1,3) +<br /> a8n(i3f+4) * gamma(i1,4) + a8n(i3f+5) * gamma(i1,5) +<br /> a8n(i3f+6) * gamma(i1,6) + a8n(i3f+7) * gamma(i1,7)<br /> };<br /> ...<br /> }<br /> i3 += 8;<br /> }</span> <span class="diffaddedchars" style="background-color:#ddfade;"><br />{quote</span> <span class="diffcontext">}</span> <span class="diffremovedchars" style="background-color: #ffe7e7; text-decoration:line-through;">}</span> </td> </tr> </table> </td> </tr> <tr> <td class="email-content-main mobile-expand " style="padding: 0px; border-collapse: collapse; border-left: 1px solid #ccc; border-right: 1px solid #ccc; border-top: 0; border-bottom: 0; padding: 0 15px 0 16px; background-color: #fff"> <table id="actions-pattern" cellspacing="0" cellpadding="0" border="0" width="100%" style="border-collapse: collapse; mso-table-lspace: 0pt; mso-table-rspace: 0pt; font-family: Arial, sans-serif; font-size: 14px; line-height: 20px; mso-line-height-rule: exactly; mso-text-raise: 1px"> <tr> <td id="actions-pattern-container" valign="middle" style="padding: 0px; border-collapse: collapse; padding: 10px 0 10px 24px; vertical-align: middle; padding-left: 0"> <table align="left" style="border-collapse: collapse; mso-table-lspace: 0pt; mso-table-rspace: 0pt"> <tr> <td class="actions-pattern-action-icon-container" style="padding: 0px; border-collapse: collapse; font-family: Arial, sans-serif; font-size: 14px; line-height: 20px; mso-line-height-rule: exactly; mso-text-raise: 0px; vertical-align: middle"> <a href="https://xtenlang.atlassian.net/browse/XTENLANG-3500#add-comment" target="_blank" title="Add Comment" style="color: #3b73af; text-decoration: none"> <img class="actions-pattern-action-icon-image" src="cid:jira-generated-image-static-comment-icon-ce71d97f-a7bc-499d-a732-0dfc27cd553d" alt="Add Comment" title="Add Comment" height="16" width="16" border="0" style="vertical-align: middle" /> </a> </td> <td class="actions-pattern-action-text-container" style="padding: 0px; border-collapse: collapse; font-family: Arial, sans-serif; font-size: 14px; line-height: 20px; mso-line-height-rule: exactly; mso-text-raise: 4px; padding-left: 5px"> <a href="https://xtenlang.atlassian.net/browse/XTENLANG-3500#add-comment" target="_blank" title="Add Comment" style="color: #3b73af; text-decoration: none">Add Comment</a> </td> </tr> </table> </td> </tr> </table> </td> </tr> <!-- there needs to be content in the cell for it to render in some clients --> <tr> <td class="email-content-rounded-bottom mobile-expand" style="padding: 0px; border-collapse: collapse; color: #fff; padding: 0 15px 0 16px; height: 5px; line-height: 5px; background-color: #fff; border-top: 0; border-left: 1px solid #ccc; border-bottom: 1px solid #ccc; border-right: 1px solid #ccc; border-bottom-right-radius: 5px; border-bottom-left-radius: 5px; mso-line-height-rule: exactly"> </td> </tr> </table> </td> </tr> <tr> <td id="footer-pattern" style="padding: 0px; border-collapse: collapse; padding: 12px 20px"> <table id="footer-pattern-container" cellspacing="0" cellpadding="0" border="0" style="border-collapse: collapse; mso-table-lspace: 0pt; mso-table-rspace: 0pt"> <tr> <td id="footer-pattern-text" class="mobile-resize-text" width="100%" style="padding: 0px; border-collapse: collapse; color: #999; font-size: 12px; line-height: 18px; font-family: Arial, sans-serif; mso-line-height-rule: exactly; mso-text-raise: 2px"> This message was sent by Atlassian JIRA <span id="footer-build-information">(v6.4-OD-16-006#64014-<span title="e47e3fa9ffcc5dfe1abb9ad8079120623d9886be" data-commit-id="e47e3fa9ffcc5dfe1abb9ad8079120623d9886be}">sha1:e47e3fa</span>)</span> </td> <td id="footer-pattern-logo-desktop-container" valign="top" style="padding: 0px; border-collapse: collapse; padding-left: 20px; vertical-align: top"> <table style="border-collapse: collapse; mso-table-lspace: 0pt; mso-table-rspace: 0pt"> <tr> <td id="footer-pattern-logo-desktop-padding" style="padding: 0px; border-collapse: collapse; padding-top: 3px"> <img id="footer-pattern-logo-desktop" src="cid:jira-generated-image-static-footer-desktop-logo-f3fc7610-18ab-4c6f-9778-260d351d1390" alt="Atlassian logo" title="Atlassian logo" width="169" height="36" class="image_fix" /> </td> </tr> </table> </td> </tr> </table> </td> </tr> </table> </body> </html> |