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Re: stepanov on sparc; sparc backend scheduling issues


Joe Buck <jbuck@racerx.synopsys.com> writes:

> > 	Sigh.  On PowerPC, the first loops look like:
> 
> [ a loop with one memory read ]
> 
> > but later loops look like:
> 
> [ a loop with two reads and a write ]
> 
> > repeatedly moving the address in and out of a stack slot instead of
> > keeping the value in a register.  This is not good.
> 
> Jason Merrill's ADDRESSOF optimization is supposed to take care of this;
> the question is why it is not working.  That is, why on the PowerPC and
> x86 do we get loops that needlessly commit the iterator to memory.
> 

Am I correct in thinking ADDRESSOF == Scalar replacement of aggregates?

It seems to do much the same thing if it's not.
At least, resultwise.

-- 
"My friend Winnie is a procrastinator.  He didn't get his
birthmark until he was eight years old.
"-Steven Wright


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