<html><head><meta http-equiv="Content-Type" content="text/html charset=windows-1252"></head><body style="word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space;">Patch #3 LGTM.<div><br></div><div>Chandler should look at #2. :-)<br><div><br></div><div>-bw</div><div><br><div><div>On Nov 19, 2013, at 2:15 PM, Robinson, Paul <<a href="mailto:Paul_Robinson@playstation.sony.com">Paul_Robinson@playstation.sony.com</a>> wrote:</div><br class="Apple-interchange-newline"><blockquote type="cite"><div lang="EN-US" link="blue" vlink="purple" style="font-family: Menlo-Regular; font-size: 12px; font-style: normal; font-variant: normal; font-weight: normal; letter-spacing: normal; line-height: 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="WordSection1" style="page: WordSection1;"><div style="margin: 0in 0in 0.0001pt; font-size: 12pt; font-family: 'Times New Roman', serif;"><span style="font-size: 11pt; font-family: Calibri, sans-serif; color: rgb(31, 73, 125);">New patch #2 (passes) and #3 (backend).<o:p></o:p></span></div><div style="margin: 0in 0in 0.0001pt; font-size: 12pt; font-family: 'Times New Roman', serif;"><span style="font-size: 11pt; font-family: Calibri, sans-serif; color: rgb(31, 73, 125);">--paulr<o:p></o:p></span></div><div style="margin: 0in 0in 0.0001pt; font-size: 12pt; font-family: 'Times New Roman', serif;"><span style="font-size: 11pt; font-family: Calibri, sans-serif; color: rgb(31, 73, 125);"> </span></div><div style="border-style: none none none solid; border-left-color: blue; border-left-width: 1.5pt; padding: 0in 0in 0in 4pt;"><div><div style="border-style: solid none none; border-top-color: rgb(181, 196, 223); border-top-width: 1pt; padding: 3pt 0in 0in;"><div style="margin: 0in 0in 0.0001pt; font-size: 12pt; font-family: 'Times New Roman', serif;"><b><span style="font-size: 10pt; font-family: Tahoma, sans-serif;">From:</span></b><span style="font-size: 10pt; font-family: Tahoma, sans-serif;"><span class="Apple-converted-space"> </span><a href="mailto:llvm-commits-bounces@cs.uiuc.edu" style="color: purple; text-decoration: underline;">llvm-commits-bounces@cs.uiuc.edu</a><span class="Apple-converted-space"> </span>[<a href="mailto:llvm-commits-bounces@cs.uiuc.edu" style="color: purple; text-decoration: underline;">mailto:llvm-commits-bounces@cs.uiuc.edu</a>]<span class="Apple-converted-space"> </span><b>On Behalf Of</b>Robinson, Paul<br><b>Sent:</b><span class="Apple-converted-space"> </span>Monday, November 18, 2013 11:53 AM<br><b>To:</b><span class="Apple-converted-space"> </span>Chandler Carruth<br><b>Cc:</b><span class="Apple-converted-space"> </span><a href="mailto:llvm-commits@cs.uiuc.edu" style="color: purple; text-decoration: underline;">llvm-commits@cs.uiuc.edu</a><span class="Apple-converted-space"> </span>commits (<a href="mailto:llvm-commits@cs.uiuc.edu" style="color: purple; text-decoration: underline;">llvm-commits@cs.uiuc.edu</a>)<br><b>Subject:</b><span class="Apple-converted-space"> </span>RE: [PATCH] Implement ‘optnone’ attribute semantics<o:p></o:p></span></div></div></div><div style="margin: 0in 0in 0.0001pt; font-size: 12pt; font-family: 'Times New Roman', serif;"><o:p> </o:p></div><div style="margin: 0in 0in 0.0001pt; font-size: 12pt; font-family: 'Times New Roman', serif;"><span style="font-size: 11pt; font-family: Calibri, sans-serif; color: rgb(31, 73, 125);">We looked at having each pass decide whether to check ‘optnone’, and it seemed that refactoring that logic into PM was cleaner. Also, PM seemed like the right place to make decisions about what passes would run…. Without PM involved, the chunk of code in each pass is more intrusive. But we can do that.<o:p></o:p></span></div><div style="margin: 0in 0in 0.0001pt; font-size: 12pt; font-family: 'Times New Roman', serif;"><span style="font-size: 11pt; font-family: Calibri, sans-serif; color: rgb(31, 73, 125);">--paulr<o:p></o:p></span></div><div style="margin: 0in 0in 0.0001pt; font-size: 12pt; font-family: 'Times New Roman', serif;"><span style="font-size: 11pt; font-family: Calibri, sans-serif; color: rgb(31, 73, 125);"> </span></div><div style="border-style: none none none solid; border-left-color: blue; border-left-width: 1.5pt; padding: 0in 0in 0in 4pt;"><div><div style="border-style: solid none none; border-top-color: rgb(181, 196, 223); border-top-width: 1pt; padding: 3pt 0in 0in;"><div style="margin: 0in 0in 0.0001pt; font-size: 12pt; font-family: 'Times New Roman', serif;"><b><span style="font-size: 10pt; font-family: Tahoma, sans-serif;">From:</span></b><span style="font-size: 10pt; font-family: Tahoma, sans-serif;"><span class="Apple-converted-space"> </span>Chandler Carruth [<a href="mailto:chandlerc@google.com" style="color: purple; text-decoration: underline;">mailto:chandlerc@google.com</a>]<span class="Apple-converted-space"> </span><br><b>Sent:</b><span class="Apple-converted-space"> </span>Monday, November 18, 2013 12:17 AM<br><b>To:</b><span class="Apple-converted-space"> </span>Robinson, Paul<br><b>Cc:</b><span class="Apple-converted-space"> </span><a href="mailto:llvm-commits@cs.uiuc.edu" style="color: purple; text-decoration: underline;">llvm-commits@cs.uiuc.edu</a><span class="Apple-converted-space"> </span>commits (<a href="mailto:llvm-commits@cs.uiuc.edu" style="color: purple; text-decoration: underline;">llvm-commits@cs.uiuc.edu</a>)<br><b>Subject:</b><span class="Apple-converted-space"> </span>Re: [PATCH] Implement ‘optnone’ attribute semantics<o:p></o:p></span></div></div></div><div style="margin: 0in 0in 0.0001pt; font-size: 12pt; font-family: 'Times New Roman', serif;"><o:p> </o:p></div><div><div><div style="margin: 0in 0in 0.0001pt; font-size: 12pt; font-family: 'Times New Roman', serif;"><o:p> </o:p></div><div><div style="margin: 0in 0in 0.0001pt; font-size: 12pt; font-family: 'Times New Roman', serif;">On Wed, Nov 13, 2013 at 4:09 PM, Robinson, Paul <<a href="mailto:Paul_Robinson@playstation.sony.com" target="_blank" style="color: purple; text-decoration: underline;">Paul_Robinson@playstation.sony.com</a>> wrote:<o:p></o:p></div><div id=":2tp"><div style="margin: 0in 0in 0.0001pt; font-size: 12pt; font-family: 'Times New Roman', serif;">Patch #2 deals with skipping optimization passes for 'optnone'<br>functions. This is probably the piece that has caused the most angst.<br>We tried to minimize the fiddling with the dreaded Pass Manager, and<br>made as straightforward and simple a change as we could come up with<br>that got the job done. That is:<br><br>We introduce a 'bool mustAlwaysRun()' method on passes, and say that<br>an 'optnone' function doesn't run any function IR, loop, or basic<br>block pass, unless that pass is marked 'mustAlwaysRun.' The default<br>for 'mustAlwaysRun' is true, so we explicitly turn it off for all the<br>Transform passes that we do not want to run on an 'optnone' function.<br>This is kind of tedious but is a mostly mechanical change.<br><br>Note that module-level passes will still consider 'optnone' functions.<o:p></o:p></div></div></div><div style="margin: 0in 0in 0.0001pt; font-size: 12pt; font-family: 'Times New Roman', serif;"><br>I don't really like this approach.<o:p></o:p></div></div><div><div style="margin: 0in 0in 0.0001pt; font-size: 12pt; font-family: 'Times New Roman', serif;"><o:p> </o:p></div></div><div><div style="margin: 0in 0in 0.0001pt; font-size: 12pt; font-family: 'Times New Roman', serif;">In re-working the pass manager stuff it is really desirable that the pass interface narrow. And if you're going to have to update each transform pass to handle this attribute anyways, it would seem better to just go into each pass's run method and add an early exit if the attribute is set. Did folks see any problems with doing that?<o:p></o:p></div></div></div></div></div></div><span><2-optnone-Passes.patch></span><span><3-optnone-CodeGen.patch></span>_______________________________________________<br>llvm-commits mailing list<br><a href="mailto:llvm-commits@cs.uiuc.edu" style="color: purple; text-decoration: underline;">llvm-commits@cs.uiuc.edu</a><br><a href="http://lists.cs.uiuc.edu/mailman/listinfo/llvm-commits" style="color: purple; text-decoration: underline;">http://lists.cs.uiuc.edu/mailman/listinfo/llvm-commits</a><br></div></blockquote></div><br></div></div></body></html>