Function fmul_fast 

pub unsafe fn fmul_fast<T>(a: T, b: T) -> T
where
    T: Copy,

🔬This is a nightly-only experimental API. (core_intrinsics)

Float multiplication that allows optimizations based on algebraic rules. Requires that inputs and output of the operation are finite, causing UB otherwise.

This intrinsic does not have a stable counterpart.