[clang] [LifetimeSafety] Implement multi-level origins (PR #168344)

[Utkarsh Saxena via cfe-commits]

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@@ -52,41 +62,118 @@ struct Origin {
   }
 };
 
-/// Manages the creation, storage, and retrieval of origins for pointer-like
-/// variables and expressions.
-class OriginManager {
+/// A list of origins representing levels of indirection for pointer-like types.
+///
+/// Each node in the list contains an OriginID representing a level of
+/// indirection. The list structure captures the multi-level nature of
+/// pointer and reference types in the lifetime analysis.
+///
+/// Examples:
+///   - For `int& x`, the list has size 2:
+///     * Root: origin for the reference storage itself (the lvalue `x`)
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usx95 wrote:

Changed to `Outer` and `Inner` to match the updated field names.

https://github.com/llvm/llvm-project/pull/168344