Bertrand Bonello’s fictionalized tribute to the life and times of “the world’s most famous Frenchman” is slick, appropriately ironic and full of flash fashion detail. But it is also two and half hours long, and totally lacks real emotion as it traverses its increasingly downbeat story. It is almost as if Bonello admires his flawed hero but can’t quite get at either his heart or soul. Fashionistas, however, will lap up the film. And the curious about Yves Saint Laurent will learn more than enough about him to chew over endlessly.