[clang] [Clang] Add __builtin_bswapg (PR #162433)

[Nikolas Klauser via cfe-commits]

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@@ -281,6 +281,10 @@ Non-comprehensive list of changes in this release
   allocator-level heap organization strategies. A feature to instrument all
   allocation functions with a token ID can be enabled via the
   ``-fsanitize=alloc-token`` flag.
+ 
+- A new generic byte swap builtin function ``__builtin_bswapg`` that extends the existing 
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philnik777 wrote:

That's just following the precedent of `__builtin_popcountg`, `__builtin_clzg` and `__builtin_ctzg`.

https://github.com/llvm/llvm-project/pull/162433