[PATCH, PR 40744] Turn down SRA a bit

[Richard Guenther]

On Thu, 6 Aug 2009, Diego Novillo wrote:

> On Thu, Aug 6, 2009 at 14:23, Martin Jambor<mjambor@suse.cz> wrote:
> 
> > This patch changes SRA in such a way that in order
> > to create a replacement, the corresponding access (group) must either:
> >
> > - be read individually multiple times or
> 
> What if the only read is inside a hot loop?  The multiple reads
> heuristic should probably use scalar evolutions to distinguish 1
> from many in the presence of loops.  Perhaps just finding out
> whether the read is inside a loop is good enough.

It would just generate

  SR_1 = var;
  D.123_2 = SR_1;

thus not do anything interesting.

> > - Â if (allow_replacements && scalar && !root->first_child)
> > + Â if (allow_replacements && scalar && !root->first_child
> > + Â  Â  Â && (root->grp_hint
> > + Â  Â  Â  Â  || (direct_read && root->grp_write)))
> 
> Clearer to line up the whole predicate vertically.

indeed.

Thanks,
Richard.