Well, at first glance, it sounded like a really stupid question. But, it is a valid point, it does happen in real life, The fact that it happens probably 100 times a day on a cable channel somewhere doesn't mean that it never happens in real life.
Rodney king was picking up a transexual prostitute once, after the incident, a plain clothes cop flashed his shield, and rodney gunned his car and tried to run him over. Cop jumped over a concrete divider and saved his own life.
In May 1991, he was arrested on suspicion of trying to run over a vice officer who allegedly found him with a transvestite prostitute in Hollywood, but no charges were filed
Here, in my hometown, two or three whacked out nutcases ran over another whacked out nutcase that they knew with a pickup truck. IIRC, they then backed up over the corpse, and hit him again. They eventually were convicted.
Don't look to me for answers. As has been said, this isn't a question about what gun will stop a charging swarm of killer bees, this is entirely about how to handle the scenario of having a car, maliciously or not, bearing down on you. The only answer to save your life is dodge. The ONLY answer. If the driver makes a second go at it, well, what the heck. he's engaged in attempted vehicular manslaughter once. All bets are off. Draw your gun, and expend all the ammo you have trying to stop the car. You might get lucky.
A newton county deputy sheriff fired a pistol through the back of an SUV whose driver had attempted to kill him, stopped the car, and killed the driver. he was crucified.
The police chief of Duquesne village fired a .40 S&W through the windshield of a car that was bearing down on him, after a fairly short high speed chase. He was canned for it.
No, It doesn't seem to be a good idea, even if you're the chief of police, the guy is trying to kill you, and he's already attempted to kill other people during a high speed chase. You'll wind up in the cell next to the driver.