[PATCH] D68209: [LiveDebugValues] Introduce entry values of unmodified params

[Adrian Prantl via Phabricator via llvm-commits]

aprantl added a comment.

I was wondering if it would make sense to let LiveDebugValues compute all available locations, and then have DbgEntityHistoryCalculator pick the best one (e.g., prefer anything over an entry value). The downside of that approach is that we'd need to reimplement some of DbgEntityHistoryCalculator in LiveDebugValues for this to work: For example whether DBG_VALUE should truncate a previous DBG_VALUE's range (e.g, if the previous one was constant) or whether it is an alternative location (such as, if a register is copied). I'm not saying that we need to do this now. But it is something we could evolve LiveDebugValues towards.



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Comment at: llvm/lib/CodeGen/LiveDebugValues.cpp:92
 
+static bool isRegOtherThanSPAndFP(const MachineOperand &Op, MachineInstr &MI,
+                                  const TargetRegisterInfo *TRI) {
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Can you adda a /// comment that explains, why this is useful / why a caller might want to know this?


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https://reviews.llvm.org/D68209