🚀 go-pugleaf

Perhaps this is the place to get a bit of myth/rumor I picked up years and
years ago straightened out.  

What i heard was that in an attempt to get the 7030 to go as fast as
possible, IBM gave it the first (?) instruction lookahead/prefetch
logic.  Not only did they prefetch the next instruction on 'ordinary'
instructions, but they also prefetched across GOTOs.  The tricky part,
as I heard it, was that for _conditional_ transfers, they put in a fair
pile of heuristics to try to *guess* which branch a conditional would
take.

The rumor basically asserted that they got the heuristics almost always
wrong [like 70+% of the time], and so when it came time to make a
similar lookahead box for the 360, they just used the SAME heuristics,
but simply reversed the 'which branch' decision... and presto: went
from being WRONG 70% of the time to being RIGHT 70% of the time.

Is any of this grounded in reality?

  /Bernie\