function roundf( x ) {
	if ( isnanf( x ) ) {
		return NaN;
	}
	if ( isNegativeZerof( x ) || ( x >= -0.5 && x < 0.0 ) ) {
		return -0.0; // -0
	}
	if ( x > 0.0 && x < 0.5 ) {
		return 0.0; // 0
	}

	// If the magnitude is big enough, there's no place for the fraction part. If we try to add 0.5 to this number, 1.0 will be added instead...
	if ( x >= 8388608.0 || x <= -8388608.0 ) {
		return x;
	}
	return floorf( float64ToFloat32( x + 0.5 ) );
}
Rounds a single-precision floating-point number to the nearest integer.

@param {number} x - input value
@returns {number} output value

@example
var v = roundf( -4.2 );
// returns -4.0

@example
var v = roundf( -4.5 );
// returns -4.0

@example
var v = roundf( -4.6 );
// returns -5.0

@example
var v = roundf( 9.99999 );
// returns 10.0

@example
var v = roundf( 9.5 );
// returns 10.0

@example
var v = roundf( 9.2 );
// returns 9.0

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

@example
var v = roundf( -0.0 );
// returns -0.0

@example
var v = roundf( Infinity );
// returns Infinity

@example
var v = roundf( -Infinity );
// returns -Infinity

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