[clang] [NFC][LifetimeSafety]: Track assignment history within a single CFGBlock (PR #196075)

[Yuan Suo via cfe-commits]

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@@ -27,6 +27,13 @@ namespace clang::lifetimes::internal {
 
 using OriginID = utils::ID<struct OriginTag>;
 
+/// Represents all possible expressions or declarations that function
+/// as the Src/Dest Origin in a visible assignment.
+using DestOriginEntity =
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suoyuan666 wrote:

Ah, the "entity" can certainly be replaced with another word; I added the comments precisely to help clear up some potential misunderstandings. I didn't really have any better ideas for the naming here. Initially, I only considered `DeclRefExpr`, but I later realized that I would encounter a wider variety of types, so I needed a unified type to refer to them all.

https://github.com/llvm/llvm-project/pull/196075