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Re: [trunk<-vta] Re: [vta] stabilize loop-unroll across insn uid variations


> On Mon, Jun 1, 2009 at 10:14 AM, Alexandre Oliva <> wrote:
> > On Oct ?7, 2008, Alexandre Oliva <> wrote:
> >
> >> compare-debug detected some differences causes by RTL loop unrolling,
> >> because debug insns changed the insn uids it uses as hashes. ?Because
> >> of this change, insns were walked in different orders, and different
> >> decisions were made.
> >
> >> I couldn't find a simple way to stabilize the uids or compute good and
> >> stable hashes without using them. ?This is the only place AFAICT that
> >> uses them as hashes, so I came up with a solution that will waste a
> >> bit of memory, but that will ensure we walk the insns in a consistent
> >> order, regardless of changes to insn uids. ?To make up for the
> >> (little) additional memory, we should get a slight speedup when
> >> walking the lists with type-safe inlinable calls, rather than walking
> >> every entry of a hashtable that's designed to be about half empty,
> >> with a type-unsafe non-inlinable callback.
> >
> > Ok for trunk?
> I'll defer to Zdenek.

looks OK to me,


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