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<p class="MsoNormal">I’d like to get another set of eyes to confirm.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">In 2019, commit 9db00f7e “DAG: propagate whether an arg is a pointer for CallingConv decisions.” added the ‘IsPointer’ field to the ArgFlagsTy struct in TargetCallingConv.h.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">This field is set in SelectionDAGBuilder, in the functions visitRet, LowerCallTo, and LowerArguments.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">In LowerArguments particularly, the field is set when a formal argument has a pointer type. However, in the case that the function has an implicit SRet argument, there is no associated formal argument to inspect. Thus, SRet is handled in
a block above the main loop.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal"><a href="https://github.com/llvm-mirror/llvm/blob/2c4ca6832fa6b306ee6a7010bfb80a3f2596f824/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp#L9565">https://github.com/llvm-mirror/llvm/blob/2c4ca6832fa6b306ee6a7010bfb80a3f2596f824/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp#L9565</a><o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">In this case, the SRet argument is always a pointer (F.getReturnType()->getPointerTo(…)), but the pointer field of the ArgFlagsTy struct is not set.<o:p></o:p></p>
<p class="MsoNormal">A simple addition of “Flags.setPointer()” fixes the issue. My review with the change is posted at:<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal"><a href="https://reviews.llvm.org/D105310">https://reviews.llvm.org/D105310</a><o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Regards,<o:p></o:p></p>
<p class="MsoNormal">J.B. Nagurne<o:p></o:p></p>
<p class="MsoNormal">Code Generation<o:p></o:p></p>
<p class="MsoNormal">Texas Instruments<o:p></o:p></p>
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