[PATCH] D61940: [DebugInfo] Don't always extend variable locations when the reg location is unchanging

[Bjorn Pettersson via Phabricator via llvm-commits]

bjope added inline comments.


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Comment at: lib/CodeGen/AsmPrinter/DbgEntityHistoryCalculator.cpp:257
+            else if (MO.getReg() != FrameReg ||
+                     !MI.getFlag(MachineInstr::FrameDestroy)) {
               for (MCRegAliasIterator AI(MO.getReg(), TRI, true); AI.isValid();
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The old solution using getFirstEpilogueInst was a little bit weird so it is nice to get rid of that. However, if I remember correctly FrameDestroy isn't used by all in-tree targets (and this change is not fully backwards compatible for OOT targets either).

Maybe that shouldn't stop us. But just something that should be taken into consideration (maybe we should make sure in-tree targets are using FrameDestroy consistently and make it obvious in commit msg or something that we now rely on FrameDestroy here).
It could even be possible to swap into relying on FrameDestory in a separate patch.



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  https://reviews.llvm.org/D61940/new/

https://reviews.llvm.org/D61940