From a software perspective, changes in flow are identical. But from a hardware standpoint, local jumps, indirect calls and returns are all predicted differentl

From a software perspective, changes in flow are identical. But from a hardware standpoint, local jumps, indirect calls and returns are all predicted differently. The spec actually has suggested forms for each kind (the author points them out in the article), so a good portion of encoding space is used on a large number of variants that will have poor performance and never be seen in practice. Especially when those bits could be used for far better purposes.