function float64ToInt32( x ) {
	// NOTE: we could also use typed-arrays to achieve the same end.
	return x|0; // asm type annotation
}
Converts a double-precision floating-point number to a signed 32-bit integer.

@param {number} x - double-precision floating-point number
@returns {integer32} signed 32-bit integer

@example
var y = float64ToInt32( 4294967295.0 );
// returns -1

@example
var y = float64ToInt32( 3.14 );
// returns 3

@example
var y = float64ToInt32( -3.14 );
// returns -3

@example
var y = float64ToInt32( NaN );
// returns 0

@example
var y = float64ToInt32( Infinity );
// returns 0

@example
var y = float64ToInt32( -Infinity );
// returns 0