It's rude, but not illegal.
Illegal would be commenting on someones breasts (nice, what are you, a C cup?), the bulge in their pants (my my, what a big...unit you have), how good their butt looks.....
These would be legal also: "your top is too low cut and revealing", "your skirt is too short, please start wearing something that comes to your knees or lower"; "your pants are too tight, please find more appropriate clothing for work....".
For the record, I cannot think of anything that would be illegal if said during a performance review that would not be illegal elsewhere in the workplace. Either it is or it isn't.
One cannot prove the intent of the manager in making the comments, but they did not come across in a manner that would infer concern.
But just for fun discussion, since this thread seems to be living on - what if the comment made was that the employee was too heavy? "Your work is great, but you're too fat."
I suspect that the answer remains the same - rude, but not illegal, but the group consensus here seems to jump to the side of the manager, and assume that the manager is expressing concern for the employee.
Rude and offensive but not illegal. As to why we "jumped on the side of the manager," it's because we can't see any reason why the manager would make those comments other than his concern for the well being of the employee.
I think we've exhausted this topic.