[clang] [Clang] Introduce scoped variants of GNU atomic functions (PR #72280)

[Matt Arsenault via cfe-commits]

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@@ -54,6 +59,16 @@ enum class SyncScope {
 
 inline llvm::StringRef getAsString(SyncScope S) {
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arsenm wrote:

I guess this is a pre-existing problem, but why don't these just match the backend string names?

https://github.com/llvm/llvm-project/pull/72280