[clang] [Clang] Add vector gather / scatter builtins to clang (PR #157895)

[Nikolas Klauser via cfe-commits]

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@@ -1256,6 +1256,18 @@ def MaskedCompressStore : Builtin {
   let Prototype = "void(...)";
 }
 
+def MaskedGather : Builtin {
+  let Spellings = ["__builtin_masked_gather"];
+  let Attributes = [NoThrow, CustomTypeChecking];
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philnik777 wrote:

I think this is `pure`?

https://github.com/llvm/llvm-project/pull/157895