[PATCH] Fix up IV-opts more for pointer plus

[Andrew_Pinski at PlayStation dot Sony dot Com]

While looking into the gzip performance regression, I noticed that IV-opts 
was not taking into account in two places POINTER_PLUS_EXPR.  The problem 
is IV-OPTs really needs to look at POINTER_PLUS_EXPR a bit more.  This 
makes IV-OPTS does that and the IV selection is better for the inner loops 
in deflact.c in gzip.

I have not done a full performance analysis to double check that this 
speeds up gzip but as mentioned before I looked into deflact.c and it 
improved the loops there.

OK?  Bootstrapped and tested on i686-linux-gnu with no regression.

Thanks,
Andrew Pinski

        * tree-ssa-loop-ivopts.c (strip_offset_1): Treat POINTER_PLUS_EXPR
        like PLUS_EXPR.
        (rewrite_use_nonlinear_expr): Likewise.

Attachment: fixivopts.diff.txt
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