re PR tree-optimization/83581 (ICE in expand_LOOP_VECTORIZED, at internal-fn.c:2397)

	PR tree-optimization/83581
	* tree-loop-distribution.c (pass_loop_distribution::execute): Return
	TODO_cleanup_cfg if any changes have been made.

	* gcc.dg/pr83581.c: New test.

From-SVN: r256055

gcc/ChangeLog

 2018-01-01  Jakub Jelinek  <jakub@redhat.com>
 
+	PR tree-optimization/83581
+	* tree-loop-distribution.c (pass_loop_distribution::execute): Return
+	TODO_cleanup_cfg if any changes have been made.
+
 	PR middle-end/83608
 	* expr.c (store_expr_with_bounds): Use simplify_gen_subreg instead of
 	convert_modes if target mode has the right side, but different mode

gcc/testsuite/ChangeLog

 2018-01-01  Jakub Jelinek  <jakub@redhat.com>
 
+	PR tree-optimization/83581
+	* gcc.dg/pr83581.c: New test.
+
 	PR c/83595
 	* gcc.dg/pr83595.c: New test.
 

gcc/testsuite/gcc.dg/pr83581.c

+/* PR tree-optimization/83581 */
+/* { dg-do compile } */
+/* { dg-options "-O3 -fno-tree-copy-prop -fno-tree-loop-im" } */
+
+int a, b, c;
+
+int
+foo (int x)
+{
+  int *d = &x;
+  while (a < 1)
+    {
+      for (b = 0; b < 2; ++b)
+        {
+          *d += !!x + 1;
+          d = &c;
+        }
+      ++a;
+    }
+  return *d;
+}

gcc/tree-loop-distribution.c

@@ -3103,7 +3103,7 @@ pass_loop_distribution::execute (function *fun)
 
   checking_verify_loop_structure ();
 
-  return 0;
+  return changed ? TODO_cleanup_cfg : 0;
 }
 
 } // anon namespace