Re: Suitable regression test for vectorizer patches?

[Richard Biener <richard dot guenther at gmail dot com>]

On Mon, Oct 29, 2018 at 7:03 PM Joern Wolfgang Rennecke
<joern.rennecke@riscy-ip.com> wrote:
>
> I want to submit some vectorizer patches, what would be a suitable
> regression test?

I am sure you have testcases, no?  For new features please make them
dg-do run ones by checking correctness.

> Preferably some native or cross test that can run on an i7 x86_64
> GNU/Linux machine.

You are probably talking about the need for specific HW features?
We have dg-requires-effective-target FOO where IIRC there are
ones that enable extra options for compilation (look for avx-runtime
or so for example).

Richard.


>
> To give an idea what code I'm patching, here are the patches I got so far:
>
>          * tree-vect-patterns.c (vect_recog_dot_prod_pattern): Recognize
> unsigned dot product pattern.
>
> Allow widening multiply-add to be used for DOT_PROF_EXPR reductions.
>          * tree-vect-data-refs.c (vect_get_smallest_scalar_type):
>          Treat WIDEN_MULT_PLUS_EXPR like WIDEN_SUM_EXPR.
>          * tree-vect-loop.c (get_initial_def_for_reduction): Likewise.
>          Get VECTYPE from STMT_VINFO_VECTYPE.
>          (vect_determine_vectorization_factor):
>          Allow vcector size input/output mismatch for reduction.
>          (vect_analyze_scalar_cycles_1): When we find a phi for a reduction,
>          put the reduction statement into the phi's STMT_VINFO_RELATED_STMT.
>          * tree-vect-patterns.c (vect_pattern_recog_1): If DOT_PROD_EXPR
> can't
>          be expanded directly, try to use WIDEN_MULT_PLUS_EXPR instead.
>
> Fix bug where a vectorizer reduction split (from
> TARGET_VECTORIZE_SPLIT_REDUCTION)
> would end up not being used.
>          * tree-vect-loop.c (vect_create_epilog_for_reduction):
>          If we split the reduction, use the result in Case 3 too.