[PATCH 3/7] vect: Factor out codes for niters smaller than vf check

[Kewen.Lin via Gcc-patches]

gcc/ChangeLog:

2020-MM-DD  Kewen Lin  <li...@gcc.gnu.org>

        * tree-vect-loop.c (known_niters_smaller_than_vf): New function, 
        factored out from ...
        (vect_analyze_loop_costing): ... here.

---
 gcc/tree-vect-loop.c | 31 ++++++++++++++++++++++---------
 1 file changed, 22 insertions(+), 9 deletions(-)

diff --git a/gcc/tree-vect-loop.c b/gcc/tree-vect-loop.c
index 4f94b4baad9..80e33b61be7 100644
--- a/gcc/tree-vect-loop.c
+++ b/gcc/tree-vect-loop.c
@@ -155,6 +155,7 @@ along with GCC; see the file COPYING3.  If not see
 static void vect_estimate_min_profitable_iters (loop_vec_info, int *, int *);
 static stmt_vec_info vect_is_simple_reduction (loop_vec_info, stmt_vec_info,
                                               bool *, bool *);
+static bool known_niters_smaller_than_vf (loop_vec_info);
 
 /* Subroutine of vect_determine_vf_for_stmt that handles only one
    statement.  VECTYPE_MAYBE_SET_P is true if STMT_VINFO_VECTYPE
@@ -1631,15 +1632,7 @@ vect_analyze_loop_costing (loop_vec_info loop_vinfo)
      vectorization factor.  */
   if (!LOOP_VINFO_FULLY_MASKED_P (loop_vinfo))
     {
-      HOST_WIDE_INT max_niter;
-
-      if (LOOP_VINFO_NITERS_KNOWN_P (loop_vinfo))
-       max_niter = LOOP_VINFO_INT_NITERS (loop_vinfo);
-      else
-       max_niter = max_stmt_executions_int (loop);
-
-      if (max_niter != -1
-         && (unsigned HOST_WIDE_INT) max_niter < assumed_vf)
+      if (known_niters_smaller_than_vf (loop_vinfo))
        {
          if (dump_enabled_p ())
            dump_printf_loc (MSG_MISSED_OPTIMIZATION, vect_location,
@@ -9231,3 +9224,23 @@ vect_iv_limit_for_full_masking (loop_vec_info loop_vinfo)
   return iv_limit;
 }
 
+/* If we know the iteration count is smaller than vectorization factor, return
+   true, otherwise return false.  */
+
+static bool
+known_niters_smaller_than_vf (loop_vec_info loop_vinfo)
+{
+  unsigned int assumed_vf = vect_vf_for_cost (loop_vinfo);
+
+  HOST_WIDE_INT max_niter;
+  if (LOOP_VINFO_NITERS_KNOWN_P (loop_vinfo))
+    max_niter = LOOP_VINFO_INT_NITERS (loop_vinfo);
+  else
+    max_niter = max_stmt_executions_int (LOOP_VINFO_LOOP (loop_vinfo));
+
+  if (max_niter != -1 && (unsigned HOST_WIDE_INT) max_niter < assumed_vf)
+    return true;
+
+  return false;
+}
+
--