Function ieee 

pub fn ieee<T>(work: impl FnOnce() -> T) -> T

Run work with IEEE 754 subnormals on the current thread.

Clears flush-to-zero and denormals-are-zero (FZ and FIZ on AArch64) for work, then restores the caller’s flushing bits exactly, also while unwinding a panic; other control bits and the status flags keep their values. A caller that keeps subnormals pays one register read, one that flushes a read and a write on each side. Work on compile-time constants only is not anchored (see the module’s soundness section).