Re: [PATCH] vect: Use statement vectype for conditional mask.

[Robin Dapp <rdapp.gcc@gmail.com>]

> But note you can explicitly specify a vector type as well, there's an
> overload for it, so we can fix the "invariant" case with the following
> (OK if you can test this on relevant targets)
> 
> diff --git a/gcc/tree-vect-loop.cc b/gcc/tree-vect-loop.cc
> index 3f59139cb01..936a3de9534 100644
> --- a/gcc/tree-vect-loop.cc
> +++ b/gcc/tree-vect-loop.cc
> @@ -8450,12 +8450,14 @@ vect_transform_reduction (loop_vec_info loop_vinfo,
>       value. */
>    bool cond_fn_p = code.is_internal_fn ()
>      && conditional_internal_fn_code (internal_fn (code)) != ERROR_MARK;
> +  int cond_index = -1;
>    if (cond_fn_p)
>      {
>        gcc_assert (code == IFN_COND_ADD || code == IFN_COND_SUB
>                   || code == IFN_COND_MUL || code == IFN_COND_AND
>                   || code == IFN_COND_IOR || code == IFN_COND_XOR);
>        gcc_assert (op.num_ops == 4 && (op.ops[1] == op.ops[3]));
> +      cond_index = 0;
>      }
> 
>    bool masked_loop_p = LOOP_VINFO_FULLY_MASKED_P (loop_vinfo);
> @@ -8486,12 +8488,13 @@ vect_transform_reduction (loop_vec_info loop_vinfo,
>    vect_get_vec_defs (loop_vinfo, stmt_info, slp_node, ncopies,
>                      single_defuse_cycle && reduc_index == 0
>                      ? NULL_TREE : op.ops[0], &vec_oprnds0,
> +                    cond_index == 0 ? truth_type_for (vectype_in) : NULL_TREE,
>                      single_defuse_cycle && reduc_index == 1
> -                    ? NULL_TREE : op.ops[1], &vec_oprnds1,
> +                    ? NULL_TREE : op.ops[1], &vec_oprnds1, NULL_TREE,
>                      op.num_ops == 4
>                      || (op.num_ops == 3
>                          && !(single_defuse_cycle && reduc_index == 2))
> -                    ? op.ops[2] : NULL_TREE, &vec_oprnds2);
> +                    ? op.ops[2] : NULL_TREE, &vec_oprnds2, NULL_TREE);

Ah, yes that's what I meant.  I had something along those lines:

+  if (!cond_fn_p)
+    {
+      vect_get_vec_defs (loop_vinfo, stmt_info, slp_node, ncopies,
+                        single_defuse_cycle && reduc_index == 0
+                        ? NULL_TREE : op.ops[0], &vec_oprnds0,
+                        single_defuse_cycle && reduc_index == 1
+                        ? NULL_TREE : op.ops[1], &vec_oprnds1,
+                        op.num_ops == 3
+                        && !(single_defuse_cycle && reduc_index == 2)
+                        ? op.ops[2] : NULL_TREE, &vec_oprnds2);
+    }
+  else
+    {
+      /* For a conditional operation, pass the truth type as vectype for the
+        mask.  */
+      gcc_assert (single_defuse_cycle && reduc_index == 1);
+      vect_get_vec_defs (loop_vinfo, stmt_info, slp_node, ncopies,
+                        op.ops[0], &vec_oprnds0,
+                        truth_type_for (vectype_in),
+                        NULL_TREE, &vec_oprnds1, NULL_TREE,
+                        op.ops[2], &vec_oprnds2, NULL_TREE);
+    }

Even though this has a bit of duplication now I prefer it slightly
because of the.  I'd hope, once fully tested (it's already running
but I'm having connection problems so don't know about the results
yet), this could go in independently of the pattern fix?

Regards
 Robin