[clang] [Clang] Add `__builtin_reduce_addf` for ordered/unordered fp reductions (PR #176160)

[Benjamin Maxwell via cfe-commits]

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@@ -1136,6 +1136,7 @@ RValue CIRGenFunction::emitBuiltinExpr(const GlobalDecl &gd, unsigned builtinID,
   case Builtin::BI__builtin_reduce_xor:
   case Builtin::BI__builtin_reduce_or:
   case Builtin::BI__builtin_reduce_and:
+  case Builtin::BI__builtin_reduce_addf:
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MacDue wrote:

It's more in line with other math/clang builtins to have the `f` as a suffix for floating-point types. 

https://github.com/llvm/llvm-project/pull/176160