RemF or ModF

Gets the modulus of a f32

(module 
  (func $fract (export "fract") (param $x f32) (result f32)
    (f32.sub
      (get_local $x)
      (f32.floor (get_local $x))
    )
  )
  (func $remf (export "remf") (param $x f32)  (param $y f32) (result f32)
    (f32.div
      (get_local $x)
      (get_local $y)
    )
    call $fract
    (get_local $y)
    f32.mul
  )
)