[PATCH] D78383: [LVI] Use Optional instead of out parameter (NFC)

[Nikita Popov via Phabricator via llvm-commits]

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Comment at: lib/Analysis/LazyValueInfo.cpp:839
+    return None;
+  ValueLatticeElement TrueVal = *OptTrueVal;
 
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My C++ foo is weak... would the proper way to write this without copying the lattice value be `TrueValue = *std::move(OptTrueVal)`?


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Comment at: lib/Analysis/LazyValueInfo.cpp:839
+    return None;
+  ValueLatticeElement TrueVal = *OptTrueVal;
 
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nikic wrote:
> My C++ foo is weak... would the proper way to write this without copying the lattice value be `TrueValue = *std::move(OptTrueVal)`?
Hm, it looks like moving an Optional moves the value (rather than making the Optional empty). As ValueLatticeElement does not specify a move constructor, I guess that means it would end up being copied, so that probably doesn't make sense.


As suggested on D76788 <https://reviews.llvm.org/D76788>, this switches the LVI implementation to return Optional<ValueLatticeElement> from various methods, instead of passing in a ValueLatticeElement reference and returning a boolean.


Repository:
  rG LLVM Github Monorepo

https://reviews.llvm.org/D78383

Files:
  lib/Analysis/LazyValueInfo.cpp

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