vect: Don't guard scalar epilogue for inverted loops [PR118211]

For loops with LOOP_VINFO_EARLY_BREAKS_VECT_PEELED we should always
enter the scalar epilogue, so avoid emitting a guard on entry to the
epilogue.

gcc/ChangeLog:

	PR tree-optimization/118211
	PR tree-optimization/116126
	* tree-vect-loop-manip.cc (vect_do_peeling): Avoid emitting an
	epilogue guard for inverted early-exit loops.

diff --git a/gcc/tree-vect-loop-manip.cc b/gcc/tree-vect-loop-manip.cc
index 15cac0fe27dfb239401f75f46dfbfba44ef94e88..4505e5d87ddb99f172bfd13e97eac6eb8f210f54 100644 (file)
--- a/gcc/tree-vect-loop-manip.cc
+++ b/gcc/tree-vect-loop-manip.cc
@@ -3530,7 +3530,9 @@ vect_do_peeling (loop_vec_info loop_vinfo, tree niters, tree nitersm1,
 
       /* If we have a peeled vector iteration we will never skip the epilog loop
         and we can simplify the cfg a lot by not doing the edge split.  */
-      if (skip_epilog || LOOP_VINFO_EARLY_BREAKS (loop_vinfo))
+      if (skip_epilog
+         || (LOOP_VINFO_EARLY_BREAKS (loop_vinfo)
+             && !LOOP_VINFO_EARLY_BREAKS_VECT_PEELED (loop_vinfo)))
        {
          guard_cond = fold_build2 (EQ_EXPR, boolean_type_node,
                                    niters, niters_vector_mult_vf);