[cwzwarich]

> Call/ret instructions work really well with branch predictors. Lots of jumps (to continuations) might not work quite as well.

On x86, the use of paired call/return is conflated with usage of the stack to store activation records. On AArch64, indirect branches can be marked with a hint bit indicating that they are a call or return, so branch prediction can work exactly the same with activation records elsewhere.