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<p class="MsoNormal">PPC64 doesn’t have 32-bit floating point values in registers, they are always 64-bit. 32-bit FP loads/stores perform implicit conversions to/from 64-bit FP. In such cases it’s not legal to do a bitcast to a 32-bit integer for the purpose
of storing.<o:p></o:p></p>
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<p class="MsoNormal"><span style="font-size:8.0pt;font-family:Consolas">Krzysztof Parzyszek
<a href="mailto:kparzysz@quicinc.com"><span style="color:#0563C1">kparzysz@quicinc.com</span></a> AI tools development<o:p></o:p></span></p>
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<p class="MsoNormal"><b>From:</b> llvm-dev <llvm-dev-bounces@lists.llvm.org> <b>On Behalf Of
</b>Matt Arsenault via llvm-dev<br>
<b>Sent:</b> Monday, February 24, 2020 1:30 PM<br>
<b>To:</b> Philip Reames <listmail@philipreames.com><br>
<b>Cc:</b> llvm-dev <llvm-dev@lists.llvm.org><br>
<b>Subject:</b> [EXT] Re: [llvm-dev] New atomic handling status<o:p></o:p></p>
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<p class="MsoNormal">On Jan 22, 2020, at 19:49, Philip Reames <<a href="mailto:listmail@philipreames.com">listmail@philipreames.com</a>> wrote:<o:p></o:p></p>
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<p class="MsoNormal"><span style="font-size:9.0pt;font-family:"Helvetica",sans-serif">In short, I hit a major stumbling block. I hadn't account for the fact that some atomic stores dependent on element type (float vs int for instance) for legality.</span><o:p></o:p></p>
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<p class="MsoNormal">I think this qualifies as a target/infrastructure bug. It should always be legal to cast the FP atomic load/store to integer. This distinction isn’t possible in GlobalISel, so it makes sense to move away from this being a situation to deal
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<p class="MsoNormal">-Matt<o:p></o:p></p>
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