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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="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> 16 March 2020 08:53<br>
<b>To:</b> Sjoerd Meijer <Sjoerd.Meijer@arm.com><br>
<b>Cc:</b> LLVM-Dev <llvm-dev@lists.llvm.org>; Sam Parker <Sam.Parker@arm.com><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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