[clang] [clang][ssaf] Add EntityId and EntityIdTable for efficient entity handling (PR #171660)

[Balázs Benics via cfe-commits]

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@@ -0,0 +1,40 @@
+//===- EntityIdTable.cpp ----------------------------------------*- C++ -*-===//
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steakhal wrote:

I've seen that in other cpp files you don't have `-*- C++ -*-` part. Strictly speaking, in cpp files the editor already knows that it's C++, so this only really applies to header files.
I don't mind this either way, but keep it consistent.
Probably, we should just have this special comment for the headers where they were designed to apply.

https://github.com/llvm/llvm-project/pull/171660