[clang] [clang] Implement constexpr support for __builtin_{clzg, ctzg} (PR #86577)

[via cfe-commits]

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@@ -12354,6 +12354,7 @@ bool IntExprEvaluator::VisitBuiltinCallExpr(const CallExpr *E,
   case Builtin::BI__builtin_clzl:
   case Builtin::BI__builtin_clzll:
   case Builtin::BI__builtin_clzs:
+  case Builtin::BI__builtin_clzg:
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overmighty wrote:

ctzg is added at line 12424.

https://github.com/llvm/llvm-project/pull/86577