8 Feb
2022
8 Feb
'22
12:16 a.m.
Thomas DeBellis <tommytimesharing(a)gmail.com>
wrote:
And then I said, "When was the last time I
actually used a JFCL and
JOV".� Well, yeah if you are doing big math, but that just doesn't
happen in day to day systems programming.� There wasn't any in all of
Galaxy, even when I fixed to to calculate dates properly.
... and the KL had double precision integer math instructions (DADD, DSUB, DMUL, DDIV)
as well as double word integer MOVEs, so you could get 72 bit integer arithmetic without
needing to deal directly with the carry flag anyway. I can't remember about the KI -
I think it had DMOVE, but not any of the arithmetic instructions.
As a practical matter the PC flags were not very useful to the average user mode
programmer.
And JFCL, with no flag bit specified, was the traditional NOP. I believe on a KL
something like TRNN was actually faster to execute, but by then nobody was willing to
switch.
Bob