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<p class="MsoNormal">Making the pointer const appears to be enough too.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">--<o:p></o:p></p>
<p class="MsoNormal">Danila<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal"><b>From:</b> llvm-dev [mailto:llvm-dev-bounces@lists.llvm.org]
<b>On Behalf Of </b>Jakub (Kuba) Kuderski via llvm-dev<br>
<b>Sent:</b> Thursday, August 8, 2019 20:23<br>
<b>To:</b> Joan Lluch <joan.lluch@icloud.com><br>
<b>Cc:</b> LLVM Developers Mailing List <llvm-dev@lists.llvm.org><br>
<b>Subject:</b> Re: [llvm-dev] Suboptimal code generated by clang+llc in quite a common scenario (?)<o:p></o:p></p>
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<p class="MsoNormal">You can add <span style="font-family:"Courier New";color:black;background:#FFFFFE">__builtin_assume(scscx == pp);</span><span style="color:black;background:#FFFFFE"> if that's your invariant -- this causes the loads to be gone using the
clang from trunk.</span><o:p></o:p></p>
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<p class="MsoNormal">On Thu, Aug 8, 2019 at 1:01 PM Joan Lluch via llvm-dev <<a href="mailto:llvm-dev@lists.llvm.org" target="_blank">llvm-dev@lists.llvm.org</a>> wrote:<o:p></o:p></p>
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<p class="MsoNormal">Hi Tim and Alex<br>
<br>
Thanks for your replies. <br>
<br>
So just to make it clear for me: does this imply that there’s indeed no way on the current version to tell the compiler or Clang to optimize this?<br>
<br>
Thanks,<br>
<br>
Joan<br>
<br>
<br>
> On 8 Aug 2019, at 18:30, Tim Northover via llvm-dev <<a href="mailto:llvm-dev@lists.llvm.org" target="_blank">llvm-dev@lists.llvm.org</a>> wrote:<br>
> <br>
> On Thu, 8 Aug 2019 at 17:08, Alex Brachet-Mialot via llvm-dev<br>
> <<a href="mailto:llvm-dev@lists.llvm.org" target="_blank">llvm-dev@lists.llvm.org</a>> wrote:<br>
>> This might not be the workaround you want because it is only available in C, but you can use restrict to allow such optimizations.<br>
> <br>
> It also doesn't work in Clang unfortunately. We can only represent<br>
> restrict on function arguments at the moment.<br>
> <br>
> Cheers.<br>
> <br>
> Tim.<br>
> _______________________________________________<br>
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<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal">-- <o:p></o:p></p>
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<p class="MsoNormal">Jakub Kuderski<o:p></o:p></p>
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