[clang] [clang][LifetimeSafety] Split live origins into persistent and block-local (PR #213543)

[Utkarsh Saxena via cfe-commits]

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@@ -336,7 +286,7 @@ class AnalysisImpl
   /// Boolean vector indexed by origin ID. If true, the origin appears in
   /// multiple basic blocks and must participate in join operations. If false,
   /// the origin is block-local and can be discarded at block boundaries.
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usx95 wrote:

consider having the same doc as the live origins with a reference to the BitVector in FactManager.
Also this doc needs to move to the field in FactManager.

https://github.com/llvm/llvm-project/pull/213543