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<p class="MsoNormal"><span style="font-family:"Calibri",sans-serif;mso-fareast-language:EN-US">No let’s not revert. But:<o:p></o:p></span></p>
<p class="MsoListParagraph" style="text-indent:-18.0pt;mso-list:l0 level1 lfo1"><![if !supportLists]><span style="font-family:Symbol;mso-fareast-language:EN-US"><span style="mso-list:Ignore">·<span style="font:7.0pt "Times New Roman"">
</span></span></span><![endif]><span style="font-family:"Calibri",sans-serif;mso-fareast-language:EN-US">Please put a list of the tickets (there are several) on the wiki page (where is the wiki page?)<o:p></o:p></span></p>
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</span></span></span><![endif]><span style="font-family:"Calibri",sans-serif;mso-fareast-language:EN-US">perf/compiler/T783<o:p></o:p></span></p>
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<![if !supportLists]><span style="font-family:"Courier New";mso-fareast-language:EN-US"><span style="mso-list:Ignore">o<span style="font:7.0pt "Times New Roman"">
</span></span></span><![endif]><span style="font-family:"Calibri",sans-serif;mso-fareast-language:EN-US">#11163: perf/compiler/T5642<o:p></o:p></span></p>
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</span></span></span><![endif]><span style="font-family:"Calibri",sans-serif;mso-fareast-language:EN-US"> <o:p></o:p></span></p>
<p class="MsoListParagraph" style="text-indent:-18.0pt;mso-list:l0 level1 lfo1"><![if !supportLists]><span style="font-family:Symbol;mso-fareast-language:EN-US"><span style="mso-list:Ignore">·<span style="font:7.0pt "Times New Roman"">
</span></span></span><![endif]><span style="font-family:"Calibri",sans-serif;mso-fareast-language:EN-US">Let’s have a flag to skip overlap testing so that there is always a workaround<o:p></o:p></span></p>
<p class="MsoListParagraph" style="text-indent:-18.0pt;mso-list:l0 level1 lfo1"><![if !supportLists]><span style="font-family:Symbol;mso-fareast-language:EN-US"><span style="mso-list:Ignore">·<span style="font:7.0pt "Times New Roman"">
</span></span></span><![endif]><span style="font-family:"Calibri",sans-serif;mso-fareast-language:EN-US">Are you happy to continue to work on these perf issues?<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-family:"Calibri",sans-serif;mso-fareast-language:EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-family:"Calibri",sans-serif;mso-fareast-language:EN-US">Simon<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-family:"Calibri",sans-serif;mso-fareast-language:EN-US"><o:p> </o:p></span></p>
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<p class="MsoNormal"><b><span lang="EN-US" style="font-size:11.0pt;font-family:"Calibri",sans-serif">From:</span></b><span lang="EN-US" style="font-size:11.0pt;font-family:"Calibri",sans-serif"> George Karachalias [mailto:george.karachalias@gmail.com]
<br>
<b>Sent:</b> 04 December 2015 09:41<br>
<b>To:</b> Simon Peyton Jones <simonpj@microsoft.com><br>
<b>Subject:</b> Re: [GHC] #11160: New exhaustiveness checker breaks ghcirun004<o:p></o:p></span></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal">Simon,<o:p></o:p></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal">On Fri, Dec 4, 2015 at 10:34 AM, GHC <<a href="mailto:ghc-devs@haskell.org" target="_blank">ghc-devs@haskell.org</a>> wrote:<o:p></o:p></p>
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<p class="MsoNormal">Comment (by simonpj):<br>
<br>
Very fast response thank you.<br>
<br>
Your commit message is very informative. Did you include the same<br>
information in a `Note` in the code, so that we don't lose the information<br>
here?<o:p></o:p></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal">I haven't yet but I can. Actually, I wanted to ask you something. At the moment<br>
I pass all the normal tests but I fail some performance tests. They <u>do compile</u> but there is a<br>
deviation from the expected and HEAD is broken. For the additional expressive power I expected<o:p></o:p></p>
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<p class="MsoNormal">some more memory and time. For example, for perf/compiler/T783.hs which has 500 guards in a<br>
single function definition I take ~5 sec to compile but the deviation in allocated bytes is 753%,<o:p></o:p></p>
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<p class="MsoNormal">compared to what the "expected" is. I feel terrible since we are really close to the freeze and I<o:p></o:p></p>
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<p class="MsoNormal">think I am stalling everyone. I know of no good way to reduce memory consumption without<o:p></o:p></p>
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<p class="MsoNormal">losing substantial expressivity. Do you think I shall revert?<o:p></o:p></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal" style="margin-bottom:12.0pt">George<o:p></o:p></p>
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<p class="MsoNormal">-- <o:p></o:p></p>
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<p class="MsoNormal"><span style="font-family:"Arial",sans-serif;color:#660000">things you own end up owning you</span><o:p></o:p></p>
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