splitting before sched2
Jeffrey A Law
law@cygnus.com
Sat Apr 4 14:20:00 GMT 1998
In message < 19980404120552.48484@dot.cygnus.com >you write:
> On Alpha at least there are a number of splits that are only enabled
> after reload is complete. I could have sworn other machines did this
> as well. My problem is that Haifa only tries splitting once, usually
> before reload.
Some machines do post reload splitting to help delay slot filling.
Recently (within the last year?) Joern added post reload splitting
to the old scheduler. I thought I had merged up all the changes
to the old scheduler into hafia, but I must have missed that one.
/* It is probably not worthwhile to try to split again in the
second pass. However, if flag_schedule_insns is not set,
the first and only (if any) scheduling pass is after reload. */
if (reload_completed == 0 || ! flag_schedule_insns)
I might argue that always splitting after reload would be a good
thing -- it would help some of the older PA7000 series machines
and there's also a case where it would help the PA8000 series.
My vote would be to unconditionally split after reload for both
schedulers.
jeff
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