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<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D">Andy<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>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D">Thanks for your quick response.
<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D">W.R.T your question on more CFG transforms, we have multiple targets that are code-based on LLVM but with minimum code-sharing. If people can realize that
this is not the right approach, sooner or later they will have the motivation to pool a variety of CFG transformations together. W.R.T the compilation time, it will take some time to change early-inlining to late-inlining. Before that happens, adding a
new pass is prohibited in the target that I am working on. So there is a code divergence between trunk-push and local development effort.
<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>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D">-Mei
<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>
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<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""> Andrew Trick [mailto:atrick@apple.com]
<br>
<b>Sent:</b> Friday, August 02, 2013 9:34 AM<br>
<b>To:</b> Ye, Mei<br>
<b>Cc:</b> Chandler Carruth; llvm commits<br>
<b>Subject:</b> Re: [patch] FlattenCFG (refactoring)<o:p></o:p></span></p>
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<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">On Aug 1, 2013, at 6:42 PM, Ye, Mei <<a href="mailto:Mei.Ye@amd.com">Mei.Ye@amd.com</a>> wrote:<o:p></o:p></p>
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<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D">Attached patch re-factor the code out from SimplifyCFG. Please review. Thanks a lot.</span><o:p></o:p></p>
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<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D"> </span><o:p></o:p></p>
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<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D">-Mei</span><o:p></o:p></p>
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<p class="MsoNormal"><span style="font-size:6.0pt;font-family:"Helvetica","sans-serif""><odc_refactor><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">Thanks for making those changes. I’m ok with this patch as-is. A couple questions though:<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 thought that FlattenCFGPass would be a target pass, AMDGPUFlattenCFG. Other targets could add their own equivalent pass but may choose to interleave other target-specific CFG transforms. Do you foresee adding more CFG transforms for AMD?
If so, you may want to start with this as a target pass so you can extend it incrementally without being forced to checkin to target-independent code.<o:p></o:p></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal">This is just curiosity, but does this patch measurably increase compile time? If so I’m curious if you can plugin a target-specific inlining pass. That could improve your compile time in general.<o:p></o:p></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal">-Andy<o:p></o:p></p>
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