[clang] [clang] Implement __builtin_rotate{left,right}g (PR #160259)

[Nikolas Klauser via cfe-commits]

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@@ -767,12 +767,24 @@ def RotateLeft : BitInt8_16_32_64BuiltinsTemplate, Builtin {
   let Prototype = "T(T, T)";
 }
 
+def RotateLeftg : Builtin {
+  let Spellings = ["__builtin_rotateleftg"];
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philnik777 wrote:

These should probably be named `__builtin_stdc_rotate_{left,right}`, since GCC already named them that way.

https://github.com/llvm/llvm-project/pull/160259