[clang] [llvm] [clang][builtin] Implement __builtin_allow_runtime_check (PR #87568)

[Vitaly Buka via cfe-commits]

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@@ -3464,6 +3464,34 @@ Query for this feature with ``__has_builtin(__builtin_trap)``.
 
 ``__builtin_arm_trap`` is lowered to the ``llvm.aarch64.break`` builtin, and then to ``brk #payload``.
 
+``__builtin_allow_runtime_check``
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vitalybuka wrote:

Not sure how to do that. I would expected that from `__builtin_nan`, but it can't do that:
https://godbolt.org/z/hWx47Gqvn

https://github.com/llvm/llvm-project/pull/87568