SH target - disable @(r0,rm) addressing mode?

Joern Rennecke
Wed Feb 5 20:35:00 GMT 2003 wrote:
> I don't think this allows the scheduler to move the loads, though?
Well, if the bulk of the arithmetic doesn't use r0, its relative
position to the loads can be changed.  If that is moving the loads
or moving the arithmetic is a matter of opinion ;-)

> The primary problem (as I see it) is the dependency of each load on the r0
> register, which limits the scheduling freedom.

If r0 was only used by loads, that would be a non-issue.
> Maybe reenabling the first instruction scheduling pass is a cleaner
> solution?

Yes, certainly.  We'd have to get it to actually work and also prevent it
from increasing register pressure too much, though.
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