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peephole vs. scheduler


I have a case where I'd like to combine two insn's into one late in the 
game.  I have a nice short define_peephole that does just what I 
want.[*]   However, the scheduler is run first, and often disrupts the 
pattern I'm looking for.  I can get the scheduler not to do that by 
setting SCHED_GROUP_P on the second insn.  But the only way I can find 
to do that is by altering the scheduler code.  I'd like to have a hook, 
something like
MD_SCHED_CHECK_FOR_GROUP(insn)
to let me do this in a more controlled fashion.  Comments?

[*] I tried various combinations of define_insn, define_expand and 
define_split without success.  Possibly I'm missing something; details 
available on request [probably Wed.], but they don't affect the main 
point here.


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