This backport contains 1 patch from gcc main stream tree.
The commit id of these patchs list as following in the order of time.

0001-re-PR-tree-optimization-92461-ICE-verify_ssa-failed-.patch
830d1b18526dd1f085e8a2e1467a6dde18fc6434

diff -Nurp a/gcc/testsuite/gcc.dg/torture/pr92461.c b/gcc/testsuite/gcc.dg/torture/pr92461.c
--- a/gcc/testsuite/gcc.dg/torture/pr92461.c	1970-01-01 08:00:00.000000000 +0800
+++ b/gcc/testsuite/gcc.dg/torture/pr92461.c	2020-07-28 19:48:09.324000000 +0800
@@ -0,0 +1,20 @@
+/* { dg-do compile } */
+/* { dg-additional-options "-ftree-vectorize" } */
+
+short int zb;
+
+void
+gs (void)
+{
+  while (zb < 1)
+    {
+      int at;
+
+      zb %= 1;
+
+      for (at = 0; at < 56; ++at)
+	zb += zb;
+
+      ++zb;
+    }
+}
diff -Nurp a/gcc/tree-vect-loop.c b/gcc/tree-vect-loop.c
--- a/gcc/tree-vect-loop.c	2020-07-28 19:47:53.896000000 +0800
+++ b/gcc/tree-vect-loop.c	2020-07-28 19:48:09.324000000 +0800
@@ -5459,8 +5459,11 @@ vect_create_epilog_for_reduction (stmt_v
           orig_name = PHI_RESULT (exit_phi);
           scalar_result = scalar_results[k];
           FOR_EACH_IMM_USE_STMT (use_stmt, imm_iter, orig_name)
-            FOR_EACH_IMM_USE_ON_STMT (use_p, imm_iter)
-              SET_USE (use_p, scalar_result);
+	    {
+	      FOR_EACH_IMM_USE_ON_STMT (use_p, imm_iter)
+		SET_USE (use_p, scalar_result);
+	      update_stmt (use_stmt);
+	    }
         }
 
       phis.release ();