On Wed, 28 Jun 2023, Tamar Christina wrote:
> Hi All,
>
> expand_vector_piecewise does not support VLA expansion as it has a hard assert
> on the type not being VLA.
>
> Instead of just failing to expand and so the call marked unsupported we ICE.
> This adjust it so we don't and can gracefully handle the expansion in support
> checks.
>
> Bootstrapped Regtested on aarch64-none-linux-gnu and no issues.
>
> Ok for master?
Hmm, do we support _any_ VLA "generic" vectors? That is, why do
we get here at all? Doesn't that mean the vectorizer creates
code that vector lowering thinks is not supported by the target?
In any case I'd expect expand_vector_operations_1 at
if (compute_type == NULL_TREE)
compute_type = get_compute_type (code, op, type);
if (compute_type == type)
return;
<---- here
new_rhs = expand_vector_operation (gsi, type, compute_type, stmt, code,
dce_ssa_names);
to be able to assert that compute_type (or even type) isn't VLA?
So, why do we arrive here?
Richard.
> Thanks,
> Tamar
>
> gcc/ChangeLog:
>
> * tree-vect-generic.cc (expand_vector_comparison): Skip piecewise if not
> constant.
>
> --- inline copy of patch --
> diff --git a/gcc/tree-vect-generic.cc b/gcc/tree-vect-generic.cc
> index
> df04a0db68da3222f43dd938f8e7adb186cd93c9..da1fd2f40d82a9fa301e6ed0b2f4c3c222d58a8d
> 100644
> --- a/gcc/tree-vect-generic.cc
> +++ b/gcc/tree-vect-generic.cc
> @@ -481,7 +481,7 @@ expand_vector_comparison (gimple_stmt_iterator *gsi, tree
> type, tree op0,
> }
> t = gimplify_build1 (gsi, VIEW_CONVERT_EXPR, type, t);
> }
> - else
> + else if (TYPE_VECTOR_SUBPARTS (type).is_constant ())
> t = expand_vector_piecewise (gsi, do_compare, type,
> TREE_TYPE (TREE_TYPE (op0)), op0, op1,
> code, false);
>
>
>
>
>
--
Richard Biener <rguent...@suse.de>
SUSE Software Solutions Germany GmbH, Frankenstrasse 146, 90461 Nuernberg,
Germany; GF: Ivo Totev, Andrew Myers, Andrew McDonald, Boudien Moerman;
HRB 36809 (AG Nuernberg)
