[vect] Disable vectorization of epilogues for loops with SIMDUID set

gcc/ChangeLog:
2019-11-08  Andre Vieira  <andre.simoesdiasvieira@arm.com>

	* tree-vect-loop.c (vect_analyze_loop): Disable epilogue vectorization
	for loops with SIMDUID set.  Enable epilogue vectorization for loops
	with SIMDLEN set after finding a main loop with a VF that matches it.

From-SVN: r277964

gcc/ChangeLog

+2019-11-08  Andre Vieira  <andre.simoesdiasvieira@arm.com>
+
+	* tree-vect-loop.c (vect_analyze_loop): Disable epilogue vectorization
+	for loops with SIMDUID set.  Enable epilogue vectorization for loops
+	with SIMDLEN set after finding a main loop with a VF that matches it.
+
 2019-11-08  Jakub Jelinek  <jakub@redhat.com>
 
 	PR target/92038

gcc/tree-vect-loop.c

@@ -2455,11 +2455,15 @@ vect_analyze_loop (class loop *loop, vec_info_shared *shared)
 	    delete loop_vinfo;
 
 	  /* Only vectorize epilogues if PARAM_VECT_EPILOGUES_NOMASK is
-	     enabled, this is not a simd loop and it is the innermost loop.  */
-	  vect_epilogues = (!loop->simdlen
+	     enabled, SIMDUID is not set, it is the innermost loop and we have
+	     either already found the loop's SIMDLEN or there was no SIMDLEN to
+	     begin with.
+	     TODO: Enable epilogue vectorization for loops with SIMDUID set.  */
+	  vect_epilogues = (!simdlen
 			    && loop->inner == NULL
 			    && PARAM_VALUE (PARAM_VECT_EPILOGUES_NOMASK)
 			    && LOOP_VINFO_PEELING_FOR_NITER (first_loop_vinfo)
+			    && !loop->simduid
 			    /* For now only allow one epilogue loop.  */
 			    && first_loop_vinfo->epilogue_vinfos.is_empty ());