tree-vrp.c (vrp_dom_walker::before_dom_childern): Push unwinding markers.

	* tree-vrp.c (vrp_dom_walker::before_dom_childern): Push unwinding
	markers.

	* g++.dg/tree-ssa/ssa-dom-thread-4.c: Update expected output.

From-SVN: r247985

gcc/ChangeLog

+2017-05-12  Jeff Law  <law@redhat.com>
+
+	* tree-vrp.c (vrp_dom_walker::before_dom_childern): Push unwinding
+	markers.
+
 2017-05-12  Peter Bergner  <bergner@vnet.ibm.com>
 
 	PR middle-end/80707

gcc/testsuite/ChangeLog

+2017-05-12  Jeff Law  <law@redhat.com>
+
+	* g++.dg/tree-ssa/ssa-dom-thread-4.c: Update expected output.
+
 2017-05-12  Peter Bergner  <bergner@vnet.ibm.com>
 
 	PR middle-end/80707

gcc/testsuite/gcc.dg/tree-ssa/ssa-dom-thread-4.c

@@ -57,12 +57,8 @@ bitmap_ior_and_compl (bitmap dst, const_bitmap a, const_bitmap b,
    we should thread all three, but due to a bug in the threading
    code we missed the edge when the first conditional is false
    (b_elt is zero, which means the second conditional is always
-   zero.  
-
-   The first two are caught by VRP1, the last is caught by DOM
-   along with another jump thread.  */
-/* { dg-final { scan-tree-dump-times "Threaded" 2 "vrp1" { target { ! logical_op_short_circuit } } } } */
-/* { dg-final { scan-tree-dump-times "Threaded" 2 "dom2" { target { ! logical_op_short_circuit } } } } */
+   zero.  VRP1 catches all three.  */
+/* { dg-final { scan-tree-dump-times "Threaded" 3 "vrp1" { target { ! logical_op_short_circuit } } } } */
 
 /* On targets that define LOGICAL_OP_NON_SHORT_CIRCUIT to 0, we split both
    "a_elt || b_elt" and "b_elt && kill_elt" into two conditions each,

gcc/tree-vrp.c

@@ -10540,6 +10540,8 @@ vrp_dom_walker::before_dom_children (basic_block bb)
 {
   gimple_stmt_iterator gsi;
 
+  m_avail_exprs_stack->push_marker ();
+  m_const_and_copies->push_marker ();
   for (gsi = gsi_start_nondebug_bb (bb); !gsi_end_p (gsi); gsi_next (&gsi))
     {
       gimple *stmt = gsi_stmt (gsi);