Re: [PATCH] [4.3 projects] Verctorizer - versioning for alias

[Victor Kaplansky <VICTORK@il.ibm.com>]

Dorit Nuzman/Haifa/IBM wrote on 16/08/2007 04:11:46 PM:
>
> Is there a testcase that catches this case?

vect-vfa-01.c catches it.

>
> >   - POINTER_PLUS_EXPR used insted of PLUS_EXPR for pointer
> > arithmentics.
> >   - Parameters "vect-max-version-for-alignment-checks" and
> > "vect-max-version-for-alias-checks" documented in invoke.texi.
>
> (make sure you pass make info/make dvi, if you haven't yet)

OK.

>
> So you're going to address the rest of the comments in a separate
> patch (cost-model updates, improved handling of interleaved-
> accesses, adding testcases that combine interleaving and versioning-
> for-aliasing, factoring out the versioning related stuff from
> vect_transform_loop)? (that would be fine with me, just want to make
> sure you're planning to address these issues too).

Yes, sure. Just forgot to mention that I'm planing to submit an
additional patch with performance and other imrovments to versioning for
alias and above issued will be addressed there.

> so I asked this before: I think you mean "don't perform **peeling**
> for alignment if versioning for alias is required", right?

Sorry, I'll fix this in the Changelog.

> I think you can use TYPE_VECTOR_SUBPARTS() instead of
> GET_MODE_SIZE (TYPE_MODE ()) (just a tiny bit more compact)

I think that it slightly different.  For example TYPE_VECTOR_SUBPARTS()
returns 4 for a vector of integers on ppc, while
GET_MODE_SIZE (TYPE_MODE ()) returns 16 - size of vector in bytes.

>
> Also, for more compact code, you could compute the vf*step once and
> reuse it for both then and else. For your consideration.
>
> +     (vinfo_for_stmt (DR_STMT (dr))))));
> +
> +      segment_length =
> + fold_convert (sizetype,
> +   fold_build2 (PLUS_EXPR, integer_type_node,
> +     fold_build2 (MULT_EXPR, integer_type_node, DR_STEP (dr),
> +    vect_factor),
> +     vector_size));
> +
> +
> +    }
> +  else
> +    {
> +      segment_length =
> + fold_convert (sizetype,
> +   fold_build2 (MULT_EXPR, integer_type_node, DR_STEP (dr),
> +         vect_factor));
> +    }
> +
> +    return segment_length;
> +}

OK, I'll address this in next patch.