<html xmlns:v="urn:schemas-microsoft-com:vml" xmlns:o="urn:schemas-microsoft-com:office:office" xmlns:w="urn:schemas-microsoft-com:office:word" xmlns:m="http://schemas.microsoft.com/office/2004/12/omml" xmlns="http://www.w3.org/TR/REC-html40">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=Windows-1252">
<meta name="Generator" content="Microsoft Word 14 (filtered medium)">
<style><!--
/* Font Definitions */
@font-face
{font-family:Calibri;
panose-1:2 15 5 2 2 2 4 3 2 4;}
@font-face
{font-family:Tahoma;
panose-1:2 11 6 4 3 5 4 4 2 4;}
@font-face
{font-family:Menlo-Regular;
panose-1:0 0 0 0 0 0 0 0 0 0;}
/* Style Definitions */
p.MsoNormal, li.MsoNormal, div.MsoNormal
{margin:0in;
margin-bottom:.0001pt;
font-size:12.0pt;
font-family:"Times New Roman","serif";}
a:link, span.MsoHyperlink
{mso-style-priority:99;
color:blue;
text-decoration:underline;}
a:visited, span.MsoHyperlinkFollowed
{mso-style-priority:99;
color:purple;
text-decoration:underline;}
p.MsoAcetate, li.MsoAcetate, div.MsoAcetate
{mso-style-priority:99;
mso-style-link:"Balloon Text Char";
margin:0in;
margin-bottom:.0001pt;
font-size:8.0pt;
font-family:"Tahoma","sans-serif";}
span.apple-converted-space
{mso-style-name:apple-converted-space;}
span.BalloonTextChar
{mso-style-name:"Balloon Text Char";
mso-style-priority:99;
mso-style-link:"Balloon Text";
font-family:"Tahoma","sans-serif";}
span.EmailStyle20
{mso-style-type:personal-reply;
font-family:"Calibri","sans-serif";
color:#1F497D;}
.MsoChpDefault
{mso-style-type:export-only;
font-size:10.0pt;}
@page WordSection1
{size:8.5in 11.0in;
margin:1.0in 1.0in 1.0in 1.0in;}
div.WordSection1
{page:WordSection1;}
--></style><!--[if gte mso 9]><xml>
<o:shapedefaults v:ext="edit" spidmax="1026" />
</xml><![endif]--><!--[if gte mso 9]><xml>
<o:shapelayout v:ext="edit">
<o:idmap v:ext="edit" data="1" />
</o:shapelayout></xml><![endif]-->
</head>
<body lang="EN-US" link="blue" vlink="purple">
<div class="WordSection1">
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D">r195317, thanks Bill!<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D">Still waiting on Chandler for #2, not that I’m impatient or anything…<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D">--paulr<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>
<div style="border:none;border-left:solid blue 1.5pt;padding:0in 0in 0in 4.0pt">
<div>
<div style="border:none;border-top:solid #B5C4DF 1.0pt;padding:3.0pt 0in 0in 0in">
<p class="MsoNormal"><b><span style="font-size:10.0pt;font-family:"Tahoma","sans-serif"">From:</span></b><span style="font-size:10.0pt;font-family:"Tahoma","sans-serif""> Bill Wendling [mailto:isanbard@gmail.com]
<br>
<b>Sent:</b> Tuesday, November 19, 2013 10:30 PM<br>
<b>To:</b> Robinson, Paul<br>
<b>Cc:</b> Chandler Carruth; llvm-commits@cs.uiuc.edu commits (llvm-commits@cs.uiuc.edu)<br>
<b>Subject:</b> Re: [PATCH] Implement ‘optnone’ attribute semantics<o:p></o:p></span></p>
</div>
</div>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Patch #3 LGTM.<o:p></o:p></p>
<div>
<p class="MsoNormal"><o:p> </o:p></p>
</div>
<div>
<p class="MsoNormal">Chandler should look at #2. :-)<o:p></o:p></p>
<div>
<p class="MsoNormal"><o:p> </o:p></p>
</div>
<div>
<p class="MsoNormal">-bw<o:p></o:p></p>
</div>
<div>
<p class="MsoNormal"><o:p> </o:p></p>
<div>
<div>
<p class="MsoNormal">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:<o:p></o:p></p>
</div>
<p class="MsoNormal"><br>
<br>
<o:p></o:p></p>
<div>
<div>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D">New patch #2 (passes) and #3 (backend).</span><o:p></o:p></p>
</div>
<div>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D">--paulr</span><o:p></o:p></p>
</div>
<div>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D"> </span><o:p></o:p></p>
</div>
<div style="border:none;border-left:solid blue 1.5pt;padding:0in 0in 0in 4.0pt">
<div>
<div style="border:none;border-top:solid #B5C4DF 1.0pt;padding:3.0pt 0in 0in 0in">
<div>
<p class="MsoNormal"><b><span style="font-size:10.0pt;font-family:"Tahoma","sans-serif"">From:</span></b><span class="apple-converted-space"><span style="font-size:10.0pt;font-family:"Tahoma","sans-serif""> </span></span><span style="font-size:10.0pt;font-family:"Tahoma","sans-serif""><a href="mailto:llvm-commits-bounces@cs.uiuc.edu"><span style="color:purple">llvm-commits-bounces@cs.uiuc.edu</span></a><span class="apple-converted-space"> </span>[<a href="mailto:llvm-commits-bounces@cs.uiuc.edu"><span style="color:purple">mailto:llvm-commits-bounces@cs.uiuc.edu</span></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"><span style="color:purple">llvm-commits@cs.uiuc.edu</span></a><span class="apple-converted-space"> </span>commits (<a href="mailto:llvm-commits@cs.uiuc.edu"><span style="color:purple">llvm-commits@cs.uiuc.edu</span></a>)<br>
<b>Subject:</b><span class="apple-converted-space"> </span>RE: [PATCH] Implement ‘optnone’ attribute semantics</span><o:p></o:p></p>
</div>
</div>
</div>
<div>
<p class="MsoNormal"> <o:p></o:p></p>
</div>
<div>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D">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.</span><o:p></o:p></p>
</div>
<div>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D">--paulr</span><o:p></o:p></p>
</div>
<div>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D"> </span><o:p></o:p></p>
</div>
<div style="border:none;border-left:solid blue 1.5pt;padding:0in 0in 0in 4.0pt">
<div>
<div style="border:none;border-top:solid #B5C4DF 1.0pt;padding:3.0pt 0in 0in 0in">
<div>
<p class="MsoNormal"><b><span style="font-size:10.0pt;font-family:"Tahoma","sans-serif"">From:</span></b><span class="apple-converted-space"><span style="font-size:10.0pt;font-family:"Tahoma","sans-serif""> </span></span><span style="font-size:10.0pt;font-family:"Tahoma","sans-serif"">Chandler
Carruth [<a href="mailto:chandlerc@google.com"><span style="color:purple">mailto:chandlerc@google.com</span></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"><span style="color:purple">llvm-commits@cs.uiuc.edu</span></a><span class="apple-converted-space"> </span>commits (<a href="mailto:llvm-commits@cs.uiuc.edu"><span style="color:purple">llvm-commits@cs.uiuc.edu</span></a>)<br>
<b>Subject:</b><span class="apple-converted-space"> </span>Re: [PATCH] Implement ‘optnone’ attribute semantics</span><o:p></o:p></p>
</div>
</div>
</div>
<div>
<p class="MsoNormal"> <o:p></o:p></p>
</div>
<div>
<div>
<div>
<p class="MsoNormal"> <o:p></o:p></p>
</div>
<div>
<div>
<p class="MsoNormal">On Wed, Nov 13, 2013 at 4:09 PM, Robinson, Paul <<a href="mailto:Paul_Robinson@playstation.sony.com" target="_blank"><span style="color:purple">Paul_Robinson@playstation.sony.com</span></a>> wrote:<o:p></o:p></p>
</div>
<div id=":2tp">
<div>
<p class="MsoNormal">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></p>
</div>
</div>
</div>
<div>
<p class="MsoNormal"><br>
I don't really like this approach.<o:p></o:p></p>
</div>
</div>
<div>
<div>
<p class="MsoNormal"> <o:p></o:p></p>
</div>
</div>
<div>
<div>
<p class="MsoNormal">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></p>
</div>
</div>
</div>
</div>
</div>
<p class="MsoNormal"><span style="font-size:9.0pt;font-family:"Menlo-Regular","serif""><2-optnone-Passes.patch><3-optnone-CodeGen.patch>_______________________________________________<br>
llvm-commits mailing list<br>
<a href="mailto:llvm-commits@cs.uiuc.edu"><span style="color:purple">llvm-commits@cs.uiuc.edu</span></a><br>
<a href="http://lists.cs.uiuc.edu/mailman/listinfo/llvm-commits"><span style="color:purple">http://lists.cs.uiuc.edu/mailman/listinfo/llvm-commits</span></a><o:p></o:p></span></p>
</div>
</div>
<p class="MsoNormal"><o:p> </o:p></p>
</div>
</div>
</div>
</div>
</body>
</html>