I would recommend breathing though!
References :
http://www.seahorsescuba.co.uk

If you are ascending rapidly (ie out of control), then an inhale can actually lead to a lung over-expansion injury. You would have to be really out of control for this to happen. If you are truely that out of control, you will probably be breathing very quick anyway.
References :

1.Never try a dive you’re not comfortable with. During descent, you should gently equalize your ears and mask. At depth, never dive outside the parameters of the dive tables or your dive computer (information that helps you avoid decompression sickness).
2.Never hold your breath while ascending. You should always ascend slowly while breathing normally.
3.Become familiar with the underwater area and its dangers. Learn which fish, coral and other hazards to avoid so injuries do not occur. Be aware of local tides and currents.
4.Never panic under water. If you become confused or afraid during a dive, stop, try to relax and think the problem through. You can also get help from your dive buddy or dive master.
5.Never dive without a buddy.
6.Always plan your dive; then always dive your plan.
7.Be sure that your diving equipment can handle the dive you have planned and that the equipment is working well.
8.Don’t drink alcohol before diving.
9.Never dive while taking medicine unless your doctor tells you it’s safe.
10.Diving can be dangerous if you have certain medical problems. Ask your doctor how diving may affect your health.
11.Cave diving is dangerous and should only be attempted by divers with proper training and equipment.
12.If you don’t feel good or if you are in pain after diving, go to the nearest emergency room immediately.
13.Don’t fly for 12 hours after a no-decompression dive, even in a pressurized airplane. If your dive required decompression stops, don’t fly for at least 24 hours.
References :
Safe diving fella