Re: [PATCH 1/2] Mid engine setup [SU]ABDL

[Richard Sandiford <richard.sandiford@arm.com>]

Oluwatamilore Adebayo <oluwatamilore.adebayo@arm.com> writes:
> From: oluade01 <oluwatamilore.adebayo@arm.com>
>
> This updates vect_recog_abd_pattern to recognize the widening
> variant of absolute difference (ABDL, ABDL2).
>
> gcc/ChangeLog:
>
> 	* internal-fn.cc (widening_fn_p, decomposes_to_hilo_fn_p):
> 	Add IFN_VEC_WIDEN_ABD to the switch statement.
> 	* internal-fn.def (VEC_WIDEN_ABD): New internal hilo optab.
> 	* optabs.def (vec_widen_sabd_optab,
> 	vec_widen_sabd_hi_optab, vec_widen_sabd_lo_optab,
> 	vec_widen_sabd_odd_even, vec_widen_sabd_even_optab,
> 	vec_widen_uabd_optab,
> 	vec_widen_uabd_hi_optab, vec_widen_uabd_lo_optab,
> 	vec_widen_uabd_odd_even, vec_widen_uabd_even_optab):
> 	New optabs.
> 	* tree-vect-patterns.cc (vect_recog_abd_pattern): Update to
> 	to build a VEC_WIDEN_ABD call if the input precision is smaller
> 	than the precision of the output.
> 	(vect_recog_widen_abd_pattern): Should an ABD expression be
> 	found preceeding an extension, replace the two with a
> 	VEC_WIDEN_ABD.

Thanks.  Testing on an updated trunk shows that we need to check
INTEGRAL_TYPE_P…

> @@ -1703,6 +1736,66 @@ vect_recog_widen_minus_pattern (vec_info *vinfo, stmt_vec_info last_stmt_info,
>  				      &subtype);
>  }
>  
> +/* Try to detect abd on widened inputs, converting IFN_ABD
> +   to IFN_VEC_WIDEN_ABD.  */
> +static gimple *
> +vect_recog_widen_abd_pattern (vec_info *vinfo, stmt_vec_info stmt_vinfo,
> +			      tree *type_out)
> +{
> +  gassign *last_stmt = dyn_cast <gassign *> (STMT_VINFO_STMT (stmt_vinfo));
> +  if (!last_stmt || !CONVERT_EXPR_CODE_P (gimple_assign_rhs_code (last_stmt)))
> +    return NULL;
> +
> +  tree last_rhs = gimple_assign_rhs1 (last_stmt);
> +
> +  tree in_type = TREE_TYPE (last_rhs);
> +  tree out_type = TREE_TYPE (gimple_assign_lhs (last_stmt));
> +  if (TYPE_PRECISION (in_type) * 2 != TYPE_PRECISION (out_type)
> +      || !TYPE_UNSIGNED (in_type))
> +    return NULL;

…here to avoid new stricter testing for TYPE_PRECISION on VECTOR_TYPEs.
I've pushed the series with that change.

Thanks again for working on this.  It's a really nice improvement.

Richard

> +
> +  vect_unpromoted_value unprom;
> +  tree op = vect_look_through_possible_promotion (vinfo, last_rhs, &unprom);
> +  if (!op || TYPE_PRECISION (TREE_TYPE (op)) != TYPE_PRECISION (in_type))
> +    return NULL;
> +
> +  stmt_vec_info abd_pattern_vinfo = vect_get_internal_def (vinfo, op);
> +  if (!abd_pattern_vinfo)
> +    return NULL;
> +
> +  abd_pattern_vinfo = vect_stmt_to_vectorize (abd_pattern_vinfo);
> +  gcall *abd_stmt = dyn_cast <gcall *> (STMT_VINFO_STMT (abd_pattern_vinfo));
> +  if (!abd_stmt
> +      || !gimple_call_internal_p (abd_stmt)
> +      || gimple_call_internal_fn (abd_stmt) != IFN_ABD)
> +    return NULL;
> +
> +  tree vectype_in = get_vectype_for_scalar_type (vinfo, in_type);
> +  tree vectype_out = get_vectype_for_scalar_type (vinfo, out_type);
> +
> +  code_helper dummy_code;
> +  int dummy_int;
> +  auto_vec<tree> dummy_vec;
> +  if (!supportable_widening_operation (vinfo, IFN_VEC_WIDEN_ABD, stmt_vinfo,
> +				       vectype_out, vectype_in,
> +				       &dummy_code, &dummy_code,
> +				       &dummy_int, &dummy_vec))
> +    return NULL;
> +
> +  vect_pattern_detected ("vect_recog_widen_abd_pattern", last_stmt);
> +
> +  *type_out = vectype_out;
> +
> +  tree abd_oprnd0 = gimple_call_arg (abd_stmt, 0);
> +  tree abd_oprnd1 = gimple_call_arg (abd_stmt, 1);
> +  tree widen_abd_result = vect_recog_temp_ssa_var (out_type, NULL);
> +  gcall *widen_abd_stmt = gimple_build_call_internal (IFN_VEC_WIDEN_ABD, 2,
> +						      abd_oprnd0, abd_oprnd1);
> +  gimple_call_set_lhs (widen_abd_stmt, widen_abd_result);
> +  gimple_set_location (widen_abd_stmt, gimple_location (last_stmt));
> +  return widen_abd_stmt;
> +}
> +
>  /* Function vect_recog_ctz_ffs_pattern
>  
>     Try to find the following pattern:
> @@ -6670,6 +6763,7 @@ static vect_recog_func vect_vect_recog_func_ptrs[] = {
>    { vect_recog_mask_conversion_pattern, "mask_conversion" },
>    { vect_recog_widen_plus_pattern, "widen_plus" },
>    { vect_recog_widen_minus_pattern, "widen_minus" },
> +  { vect_recog_widen_abd_pattern, "widen_abd" },
>    /* These must come after the double widening ones.  */
>  };