The "combat roll" came up in a thread last yere.
Nobody seemed to be too impressed with the concept and few had very much knowledge of it being used outside of Hollywood movies.
I finally found an example, not a great example, but the only thing like it that I have seen.
After a chase by officers, the suspects' truck crashed into a telephone pole. On approaching the vehicle, they see it only has teenagers. At that point, they considered the situation diffused (maybe thinking that they were just joyriding kids?) and start with post accident activities of calling for medical and trying to assess the "kids'" situation inside.
So one officer is watching the the truck. Another has returned to his car. A third has just rolled on scene.
The occupants won't let the officer get the passenger side door open and so the officer walks around to the driver's side and suspects something is amiss and draws his gun, issues commands, and is shot by one of the suspects. He goes down and then escapes to the concealment of the woods by rolling. Unlike the Hollywood version, the injured officer does not enter the roll from standing as he was already down. He enters it from a crawling position He does not bounce up with his gun and join the fight as he lost his gun when he was shot.
I don't know how well he considered his roll option. The roll did keep him below much of the initial shots fired, but he rolled behind the suspects which probably was not ideal given his fellow officers were shooting at the suspects. However, going in that direction took him out of the shooter's field of view that was toward the officers shooting. This meant that the suspects were not likely to try shooting him again.
After the shooting started, the officer that had gone to handle medical draws his gun and aims at the truck. The shooting suspect peers around the rear of the cab and starts shooting at the officer handling medical. The officer was very fortunate as the suspect apparently has a flinch and puts his first few rounds toward the officer into the ground.
So what of the combat roll? While it might have been handy to use as a low level way to traverse the open distance between the officers and the truck, neither of the unwounded officers used it. Only the wounded officer used.