uaarch64 has very little legacy stuff left. When ARM announced A715, they got rid of uaarch32 and said it got them a 75% reduction in the size of the decoder w

uaarch64 has very little legacy stuff left. When ARM announced A715, they got rid of uaarch32 and said it got them a 75% reduction in the size of the decoder while increasing the width of the decoder from 4 to 5-wide. They even got rid of the uop-cache because the new encoding was so much smaller and efficient that it didn't make sense to keep it around.