<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=utf-8">
<meta name="Generator" content="Microsoft Word 15 (filtered medium)">
<style><!--
/* Font Definitions */
@font-face
{font-family:"Cambria Math";
panose-1:2 4 5 3 5 4 6 3 2 4;}
@font-face
{font-family:Calibri;
panose-1:2 15 5 2 2 2 4 3 2 4;}
/* Style Definitions */
p.MsoNormal, li.MsoNormal, div.MsoNormal
{margin:0in;
margin-bottom:.0001pt;
font-size:11.0pt;
font-family:"Calibri",sans-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.MsoPlainText, li.MsoPlainText, div.MsoPlainText
{mso-style-priority:99;
mso-style-link:"Plain Text Char";
margin:0in;
margin-bottom:.0001pt;
font-size:11.0pt;
font-family:"Courier New";}
p.msonormal0, li.msonormal0, div.msonormal0
{mso-style-name:msonormal;
mso-margin-top-alt:auto;
margin-right:0in;
mso-margin-bottom-alt:auto;
margin-left:0in;
font-size:11.0pt;
font-family:"Calibri",sans-serif;}
span.EmailStyle19
{mso-style-type:personal-reply;
font-family:"Courier New";
color:#44546A;
font-weight:normal;
font-style:normal;
text-decoration:none none;}
span.PlainTextChar
{mso-style-name:"Plain Text Char";
mso-style-priority:99;
mso-style-link:"Plain Text";
font-family:"Courier New";}
.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-family:"Courier New";color:#44546A">What I did was run the test suite and examine every failure. In every test that had an fsub get changed into an fneg I updated the test. That only left a few failures:<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-family:"Courier New";color:#44546A"><o:p> </o:p></span></p>
<p class="MsoPlainText"> LLVM :: Transforms/InstCombine/cos-1.ll<o:p></o:p></p>
<p class="MsoPlainText"> LLVM :: Transforms/InstCombine/fsub.ll<o:p></o:p></p>
<p class="MsoPlainText"> LLVM :: Transforms/Reassociate/canonicalize-neg-const.ll<o:p></o:p></p>
<p class="MsoPlainText"> LLVM :: Transforms/Reassociate/reassoc-intermediate-fnegs.ll<o:p></o:p></p>
<p class="MsoNormal"><span style="font-family:"Courier New";color:#44546A"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-family:"Courier New";color:#44546A">These four need work beyond changing fsub’s into fneg’s.
<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:10.0pt;font-family:"Courier New";color:#44546A">--</span><span style="color:#44546A">
<br>
</span><span style="font-size:10.0pt;font-family:"Courier New";color:#44546A">Kevin P. Neal</span><span style="color:#44546A"><br>
</span><span style="font-size:10.0pt;font-family:"Courier New";color:#44546A">SAS/C and SAS/C++ Compiler<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:10.0pt;font-family:"Courier New";color:#44546A">Host Research and Development<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:10.0pt;font-family:"Courier New";color:#44546A">SAS Institute, Inc.</span><span style="color:#44546A"><o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-family:"Courier New";color:#44546A"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-family:"Courier New";color:#44546A"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-family:"Courier New";color:#44546A"><o:p> </o:p></span></p>
<div>
<div style="border:none;border-top:solid #E1E1E1 1.0pt;padding:3.0pt 0in 0in 0in">
<p class="MsoNormal"><b>From:</b> Sanjay Patel <spatel@rotateright.com> <br>
<b>Sent:</b> Tuesday, May 07, 2019 11:44 AM<br>
<b>To:</b> Kevin Neal <Kevin.Neal@sas.com><br>
<b>Cc:</b> cameron.mcinally@nyu.edu; Matthew.Arsenault@amd.com; andrew.kaylor@intel.com; mcrosier@codeaurora.org; wei.ding2@amd.com; hiraditya@msn.com; llvm-commits@lists.llvm.org; jun.l@samsung.com<br>
<b>Subject:</b> Re: [PATCH] D61604: [InstCombine] sink FP negation of operands through select<o:p></o:p></p>
</div>
</div>
<p class="MsoNormal"><o:p> </o:p></p>
<p><b><i><span style="font-size:12.0pt;font-family:"Arial",sans-serif;color:red">EXTERNAL</span></i></b><span style="font-size:12.0pt;font-family:"Arial",sans-serif;color:red">
</span><o:p></o:p></p>
<div>
<div>
<div>
<p class="MsoNormal"><o:p> </o:p></p>
</div>
<div>
<div>
<p class="MsoNormal">On Tue, May 7, 2019 at 7:16 AM Kevin Neal <<a href="mailto:Kevin.Neal@sas.com">Kevin.Neal@sas.com</a>> wrote:<o:p></o:p></p>
</div>
<blockquote style="border:none;border-left:solid #CCCCCC 1.0pt;padding:0in 0in 0in 6.0pt;margin-left:4.8pt;margin-right:0in">
<p class="MsoNormal"><br>
How should we handle regressions in code quality that are exposed by tests?<o:p></o:p></p>
</blockquote>
<div>
<p class="MsoNormal"><o:p> </o:p></p>
</div>
<div>
<p class="MsoNormal">One idea I had (or I may be remembering someone else's suggestion) was to grep the existing IR regression tests for 'fsub -0.0', then create a sibling test using fneg. If that doesn't result in the same output, then we need to do some pattern
matching enhancement.<o:p></o:p></p>
</div>
</div>
</div>
</div>
</div>
</body>
</html>