[PATCH] D83561: [ScheduleDAG] Move DBG_VALUEs after first term forward.

Mon Jul 13 12:37:45 PDT 2020

fhahn marked an inline comment as done.
fhahn added inline comments.

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Comment at: llvm/lib/CodeGen/SelectionDAG/ScheduleDAGSDNodes.cpp:1037-1039
+  // In some cases, DBG_VALUEs might be inserted after the first terminator,
+  // which results in an invalid MBB. If that happens, move the DBG_VALUEs
+  // before the first terminator.
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paquette wrote:
> Does this ever happen with anything other than tail calls?
I am not sure. I think the reason this happens here is that the instruction with the debug value attached (the `sdiv`) gets folded with the return instruction into `TCRETURNdi` during SelectionDAG. And now the DBG_VALUE is attached to the TCRETURN.

Repository:
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  https://reviews.llvm.org/D83561/new/

https://reviews.llvm.org/D83561