In Star Fox for the SNES Pepper Hare would ask of you to do a barrel roll. Doing a barrel roll in Star Fox is to press the shoulder buttons twice, pressing L shoulder button then L again would make the R-wing do a barrel roll counter clockwise, pressing the R shoulder button then R again would make the R-wing do a barrel roll clockwise.
utlizing a barrel roll is extremly usful in Star Fox as it deflects most objects fired at the R-wing
The term "Do a barrel roll" is commonly mistaken that it froms from Star Fox 64. It did not. But it was spoken by a voice actor for Peppy Hare in Star Fox 64. In Star Foxes training mode, the game would give you simple tasks. Eventually 3 other R-wings would fly around as you were told to do the same as them, after sometime before the 3 other R-wings would barrel roll Peppy would tell you to do a barrel roll.
Peppy: Do a Barrel Roll! (text only)
(The player decides if they want to do a barrel roll)
Guy 1: You should do a barrel roll...
Guy 2: Dude, shut up!
Guy 1: Ha you died, only if you would have done a barrel roll!