[Bug tree-optimization/64946] [AArch64] gcc.target/aarch64/vect-abs-compile.c - "abs" vectorization fails for char/short types

[rguenther at suse dot de]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=64946

--- Comment #7 from rguenther at suse dot de <rguenther at suse dot de> ---
On Thu, 26 Feb 2015, vekumar at gcc dot gnu.org wrote:

> https://gcc.gnu.org/bugzilla/show_bug.cgi?id=64946
> 
> vekumar at gcc dot gnu.org changed:
> 
>            What    |Removed                     |Added
> ----------------------------------------------------------------------------
>                  CC|                            |rguenth at gcc dot gnu.org
> 
> --- Comment #3 from vekumar at gcc dot gnu.org ---
> Richard, 
> 
> As per your suggestion, adding a pattern for type demotion in match.pd solves
> this.
> 
> (simplify
>  ( convert (abs (convert@1 @0)))
>  ( if (INTEGRAL_TYPE_P (type)
>       /* We check for type compatibility between @0 and @1 below,
>          so there's no need to check that @1/@3 are integral types.  */
>       && INTEGRAL_TYPE_P (TREE_TYPE (@0))
>       && INTEGRAL_TYPE_P (TREE_TYPE (@1))
>       /* The precision of the type of each operand must match the
>          precision of the mode of each operand, similarly for the
>          result.  */
>       && (TYPE_PRECISION (TREE_TYPE (@0))
>           == GET_MODE_PRECISION (TYPE_MODE (TREE_TYPE (@0))))
>       && (TYPE_PRECISION (TREE_TYPE (@1))
>           == GET_MODE_PRECISION (TYPE_MODE (TREE_TYPE (@1))))
>       && TYPE_PRECISION (type) == GET_MODE_PRECISION (TYPE_MODE (type))
>       /* The inner conversion must be a widening conversion.  */
>       && TYPE_PRECISION (TREE_TYPE (@1)) > TYPE_PRECISION (TREE_TYPE (@0))
>       && ((GENERIC
>            && (TYPE_MAIN_VARIANT (TREE_TYPE (@0))
>                == TYPE_MAIN_VARIANT (type)))
>           || (GIMPLE
>               && types_compatible_p (TREE_TYPE (@0), type))))
>    (abs @0)))
> 
> 
> I have not yet tested it. Will it have implication on targets that does not
> support vectorization with short/char types?

I don't see how it could.