ARM64 (AArch64) ripped out a lot of the original design ideas. No conditional execution, and the program counter is no longer directly addressable. This does

ARM64 (AArch64) ripped out a lot of the original design ideas. No conditional execution, and the program counter is no longer directly addressable. This does increase performance, at the cost of code density (no thumb instructions either). Fujitsu's ARM supercomputer was the first that I'd heard of removing all 32-bit support, but mainline designs are about to do the same with phones.