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Hi Roger,</div>
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I don't have anything on my TODO list for the analysis, so any patches welcome! And, of course, I'll happily help out with reviews.</div>
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cheers,</div>
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<p style="margin-top: 0px; margin-bottom: 0px;font-family:"Times New Roman""><span style="font-family:Calibri,Helvetica,sans-serif">Sam Parker</span></p>
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<div id="divRplyFwdMsg" dir="ltr"><font face="Calibri, sans-serif" style="font-size:11pt" color="#000000"><b>From:</b> Roger Ferrer Ibáñez <rofirrim@gmail.com><br>
<b>Sent:</b> 23 March 2020 13:52<br>
<b>To:</b> Sam Parker <Sam.Parker@arm.com><br>
<b>Cc:</b> LLVM-Dev <llvm-dev@lists.llvm.org>; Sjoerd Meijer <Sjoerd.Meijer@arm.com><br>
<b>Subject:</b> Re: [llvm-dev] Redundant copies</font>
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<div>Hi Sam,</div>
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<div>just a short question: I was taking a look at the RDA pass and it doesn't currently handle RegMasks. Is in your backlog to add support for those?</div>
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<div>I am asking because I found myself analyzing across call instructions. Not taking the regmasks into account leads to inexact results and needs extra care. So I wondered if this was already in your phabricator backlog. I made a first implementation downstream
but before I continue with it I wanted to make sure I'm not stepping on your toes :)<br>
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<div>Thank you very much,<br>
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<div dir="ltr" class="x_gmail_attr">Missatge de Sjoerd Meijer <<a href="mailto:Sjoerd.Meijer@arm.com">Sjoerd.Meijer@arm.com</a>> del dia dl., 16 de març 2020 a les 13:28:<br>
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Yep, exactly that. We see quite a lot of them, most of them get cleaned up, but not always...</div>
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Cheers.</div>
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<div id="x_gmail-m_1288950087438718093divRplyFwdMsg" dir="ltr"><font face="Calibri, sans-serif" color="#000000" style="font-size:11pt"><b>From:</b> Roger Ferrer Ibáñez <<a href="mailto:rofirrim@gmail.com" target="_blank">rofirrim@gmail.com</a>><br>
<b>Sent:</b> 16 March 2020 08:53<br>
<b>To:</b> Sjoerd Meijer <<a href="mailto:Sjoerd.Meijer@arm.com" target="_blank">Sjoerd.Meijer@arm.com</a>><br>
<b>Cc:</b> LLVM-Dev <<a href="mailto:llvm-dev@lists.llvm.org" target="_blank">llvm-dev@lists.llvm.org</a>>; Sam Parker <<a href="mailto:Sam.Parker@arm.com" target="_blank">Sam.Parker@arm.com</a>><br>
<b>Subject:</b> Re: [llvm-dev] Redundant copies</font>
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<div>At this point however it doesn't (obviously) look like one (it still using different vregs) which suggests it might require a bit more of work to discover something that will ultimately lead to a redundant copy. I will investigate this option as well.<br>
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<div>I correct myself here: in the MIR dumps (for this example) right after copy coalescing the copy is redundant even at vregs</div>
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<div><span style="font-family:monospace"> %14:gpr = COPY %0 <br>
BEQ %6, $x0, %bb.3 <br>
PseudoBR %bb.1 <br>
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bb.1.for.body.preheader:<br>
%14:gpr = COPY %0</span></div>
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<div>Kind regards,<br>
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-- <br>
<div dir="ltr" class="x_gmail_signature">Roger Ferrer Ibáñez<br>
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