Hi All,
Here's a respin of this patch with the requested changes.
Thanks,
Tamar
gcc/ChangeLog:
* tree-vect-loop.c (vect_dissolve_slp_only_patterns): New
(vect_dissolve_slp_only_groups): Call vect_dissolve_slp_only_patterns.
> -----Original Message-----
> From: Gcc-patches <gcc-patches-boun...@gcc.gnu.org> On Behalf Of Tamar
> Christina
> Sent: Friday, September 25, 2020 3:28 PM
> To: gcc-patches@gcc.gnu.org
> Cc: nd <n...@arm.com>; rguent...@suse.de; o...@ucw.cz
> Subject: [PATCH v2 4/16]middle-end: Add dissolve code for when SLP fails
> and non-SLP loop vectorization is to be tried.
>
> Hi All,
>
> This adds the dissolve code to undo the patterns created by the pattern
> matcher in case SLP is to be aborted.
>
> As mentioned in the cover letter this has one issue in that the number of
> copies can needed can change depending on whether TWO_OPERATORS is
> needed or not.
>
> Because of this I don't analyze the original statement when it's replaced by a
> pattern and attempt to correct it here by analyzing it after dissolve.
>
> This however seems too late and I would need to change the unroll factor,
> which seems a bit odd. Any advice would be appreciated.
>
> Bootstrapped Regtested on aarch64-none-linux-gnu and no issues.
>
> Thanks,
> Tamar
>
> gcc/ChangeLog:
>
> * tree-vect-loop.c (vect_dissolve_slp_only_patterns): New
> (vect_dissolve_slp_only_groups): Call
> vect_dissolve_slp_only_patterns.
>
> --
diff --git a/gcc/tree-vect-loop.c b/gcc/tree-vect-loop.c
index 6fa185daa2836062814f9c9a6659011a3153c6a2..9601a83edcb05e994e27d4bb16a537190ad8471d 100644
--- a/gcc/tree-vect-loop.c
+++ b/gcc/tree-vect-loop.c
@@ -1979,6 +1979,63 @@ vect_get_datarefs_in_loop (loop_p loop, basic_block *bbs,
return opt_result::success ();
}
+/* For every SLP only pattern created by the pattern matched rooted in ROOT
+ restore the relevancy of the original statements over those of the pattern
+ and destroy the pattern relationship. This restores the SLP tree to a state
+ where it can be used when SLP build is cancelled or re-tried. */
+
+static void
+vect_dissolve_slp_only_patterns (loop_vec_info loop_vinfo,
+ hash_set<slp_tree> *visited, slp_tree root)
+{
+ if (!root || visited->contains (root))
+ return;
+
+ unsigned int i;
+ slp_tree node;
+ stmt_vec_info related_stmt_info;
+ stmt_vec_info stmt_info = SLP_TREE_REPRESENTATIVE (root);
+
+ visited->add (root);
+
+ if (stmt_info && STMT_VINFO_SLP_VECT_ONLY (stmt_info)
+ && (related_stmt_info = STMT_VINFO_RELATED_STMT (stmt_info)) != NULL)
+ {
+ if (dump_enabled_p ())
+ dump_printf_loc (MSG_NOTE, vect_location,
+ "dissolving relevancy of %G",
+ STMT_VINFO_STMT (stmt_info));
+ STMT_VINFO_RELEVANT (stmt_info) = vect_unused_in_scope;
+ STMT_VINFO_RELEVANT (related_stmt_info) = vect_used_in_scope;
+ STMT_VINFO_IN_PATTERN_P (related_stmt_info) = false;
+ STMT_SLP_TYPE (related_stmt_info) = loop_vect;
+ }
+
+ FOR_EACH_VEC_ELT (SLP_TREE_CHILDREN (root), i, node)
+ vect_dissolve_slp_only_patterns (loop_vinfo, visited, node);
+}
+
+/* Lookup any SLP Only Pattern statements created by the SLP pattern matcher in
+ all slp_instances in LOOP_VINFO and undo the relevancy of statements such
+ that the original SLP tree before the pattern matching is used. */
+
+static void
+vect_dissolve_slp_only_patterns (loop_vec_info loop_vinfo)
+{
+
+ unsigned int i;
+ hash_set<slp_tree> visited;
+
+ DUMP_VECT_SCOPE ("vect_dissolve_slp_only_patterns");
+
+ /* Unmark any SLP only patterns as relevant and restore the STMT_INFO of the
+ related instruction. */
+ slp_instance instance;
+ FOR_EACH_VEC_ELT (LOOP_VINFO_SLP_INSTANCES (loop_vinfo), i, instance)
+ vect_dissolve_slp_only_patterns (loop_vinfo, &visited,
+ SLP_INSTANCE_TREE (instance));
+}
+
/* Look for SLP-only access groups and turn each individual access into its own
group. */
static void
@@ -2510,6 +2567,9 @@ again:
/* Ensure that "ok" is false (with an opt_problem if dumping is enabled). */
gcc_assert (!ok);
+ /* Dissolve any SLP patterns created by the SLP pattern matcher. */
+ vect_dissolve_slp_only_patterns (loop_vinfo);
+
/* Try again with SLP forced off but if we didn't do any SLP there is
no point in re-trying. */
if (!slp)
