function ahaversinf( x ) {
	return float64ToFloat32( 2.0 * asinf( sqrtf( x ) ) );
}
Computes the inverse half-value versed sine of a single-precision floating-point number.

@param {number} x - input value
@returns {number} inverse half-value versed sine

@example
var v = ahaversinf( 0.0 );
// returns 0.0

@example
var v = ahaversinf( 1.0 );
// returns ~3.1416

@example
var v = ahaversinf( 0.5 );
// returns ~1.5708

@example
var v = ahaversinf( NaN );
// returns NaN