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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