[clang] [llvm] [IR][IPO] Don't rewrite the signature of optnone functions (PR #211804)

[Shilei Tian via cfe-commits]

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@@ -2551,6 +2551,8 @@ fn -> other_fn -> other_fn ; fn is norecurse
 `optnone`
 :   This function attribute indicates that most optimization passes will skip
     this function, with the exception of interprocedural optimization passes.
+    Interprocedural passes may still analyze this function, transform its body,
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shiltian wrote:

I don't know enough about history, but It is really weird that `optnone` implies that IPO can still do some local changes…I thought `optnone` reads "optimization none".

https://github.com/llvm/llvm-project/pull/211804