Function s_barrier_signal_isfirst 

pub unsafe fn s_barrier_signal_isfirst<const BARRIER_TYPE: i32>() -> bool

🔬This is a nightly-only experimental API. (stdarch_amdgpu #149988)

Available on target_arch=amdgpu only.

Signal a specific barrier type.

Only for non-named barriers. Provides access to the s_barrier_signal_first instruction; additionally ensures that the result value is valid even when the intrinsic is used from a wavefront that is not running in a workgroup.