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-92085-ICE-tree-check-expecte.patch
3c8e341b996546607fa1f39a0fd9a9d7c2c38214

diff -Nurp a/gcc/testsuite/gcc.dg/tree-ssa/pr92085-1.c b/gcc/testsuite/gcc.dg/tree-ssa/pr92085-1.c
--- a/gcc/testsuite/gcc.dg/tree-ssa/pr92085-1.c	1970-01-01 08:00:00.000000000 +0800
+++ b/gcc/testsuite/gcc.dg/tree-ssa/pr92085-1.c	2020-07-09 11:05:23.136000000 +0800
@@ -0,0 +1,20 @@
+/* { dg-do compile } */
+/* { dg-options "-O1 -fexceptions -fnon-call-exceptions -ftree-loop-vectorize -fno-tree-sink --param dse-max-alias-queries-per-store=2 -w" } */
+
+void
+di (int y9, int qw)
+{
+  if ((int) &y9 != 0)
+    {
+      int py;
+      int **fq = &py;
+
+      while (qw < 1)
+        {
+          if ((0 < (**fq ? **fq : (**fq = 1))) / (**fq = y9))
+            ;
+
+          ++qw;
+        }
+    }
+}
diff -Nurp a/gcc/testsuite/gcc.dg/tree-ssa/pr92085-2.c b/gcc/testsuite/gcc.dg/tree-ssa/pr92085-2.c
--- a/gcc/testsuite/gcc.dg/tree-ssa/pr92085-2.c	1970-01-01 08:00:00.000000000 +0800
+++ b/gcc/testsuite/gcc.dg/tree-ssa/pr92085-2.c	2020-07-09 11:05:23.136000000 +0800
@@ -0,0 +1,29 @@
+/* { dg-do compile } */
+/* { dg-options "-O1 -ftree-loop-vectorize -fno-tree-dce -fno-tree-sink -w" } */
+
+int a8;
+
+void
+c1 (int oz, int dk, int ub)
+{
+  int *hd = 0;
+  long int *th = &dk;
+
+  while (ub < 1)
+    {
+      oz || dk;
+      ++ub;
+    }
+
+  while (oz < 2)
+    {
+      long int *lq = &oz;
+
+      (*hd < (*lq = *th)) < oz;
+
+      if (oz == 0)
+        *th = a8 = oz;
+
+      *lq = 0;
+    }
+}
diff -Nurp a/gcc/tree-if-conv.c b/gcc/tree-if-conv.c
--- a/gcc/tree-if-conv.c	2020-07-09 11:04:58.832000000 +0800
+++ b/gcc/tree-if-conv.c	2020-07-09 11:05:23.136000000 +0800
@@ -2984,10 +2984,11 @@ ifcvt_local_dce (class loop *loop)
 	  ao_ref write;
 	  ao_ref_init (&write, lhs);
 
-          if (dse_classify_store (&write, stmt, false, NULL, NULL, latch_vdef)
-              == DSE_STORE_DEAD)
-            delete_dead_or_redundant_assignment (&gsi, "dead");
-	  gsi_next (&gsi);
+	  if (dse_classify_store (&write, stmt, false, NULL, NULL, latch_vdef)
+	      == DSE_STORE_DEAD)
+	    delete_dead_or_redundant_assignment (&gsi, "dead");
+	  else
+	    gsi_next (&gsi);
 	  continue;
 	}