--- a/hotspot/src/share/vm/opto/loopopts.cpp	Tue Sep 15 12:59:51 2015 +0000
+++ b/hotspot/src/share/vm/opto/loopopts.cpp	Tue Sep 15 13:08:43 2015 +0200
@@ -653,7 +653,6 @@
   return iff->in(1);
 }
 
-#ifdef ASSERT
 static void enqueue_cfg_uses(Node* m, Unique_Node_List& wq) {
   for (DUIterator_Fast imax, i = m->fast_outs(imax); i < imax; i++) {
     Node* u = m->fast_out(i);
@@ -667,7 +666,6 @@
     }
   }
 }
-#endif
 
 // Try moving a store out of a loop, right before the loop
 Node* PhaseIdealLoop::try_move_store_before_loop(Node* n, Node *n_ctrl) {
@@ -687,11 +685,15 @@
     // written at iteration i by the second store could be overwritten
     // at iteration i+n by the first store: it's not safe to move the
     // first store out of the loop
-    // - nothing must observe the Phi memory: it guarantees no read
-    // before the store and no early exit out of the loop
-    // With those conditions, we are also guaranteed the store post
-    // dominates the loop head. Otherwise there would be extra Phi
-    // involved between the loop's Phi and the store.
+    // - nothing must observe the memory Phi: it guarantees no read
+    // before the store, we are also guaranteed the store post
+    // dominates the loop head (ignoring a possible early
+    // exit). Otherwise there would be extra Phi involved between the
+    // loop's Phi and the store.
+    // - there must be no early exit from the loop before the Store
+    // (such an exit most of the time would be an extra use of the
+    // memory Phi but sometimes is a bottom memory Phi that takes the
+    // store as input).
 
     if (!n_loop->is_member(address_loop) &&
         !n_loop->is_member(value_loop) &&
@@ -699,9 +701,10 @@
         mem->outcnt() == 1 &&
         mem->in(LoopNode::LoopBackControl) == n) {
 
-#ifdef ASSERT
-      // Verify that store's control does post dominate loop entry and
-      // that there's no early exit of the loop before the store.
+      assert(n_loop->_tail != NULL, "need a tail");
+      assert(is_dominator(n_ctrl, n_loop->_tail), "store control must not be in a branch in the loop");
+
+      // Verify that there's no early exit of the loop before the store.
       bool ctrl_ok = false;
       {
         // Follow control from loop head until n, we exit the loop or
@@ -709,7 +712,7 @@
         ResourceMark rm;
         Unique_Node_List wq;
         wq.push(n_loop->_head);
-        assert(n_loop->_tail != NULL, "need a tail");
+
         for (uint next = 0; next < wq.size(); ++next) {
           Node *m = wq.at(next);
           if (m == n->in(0)) {
@@ -722,24 +725,27 @@
             break;
           }
           enqueue_cfg_uses(m, wq);
+          if (wq.size() > 10) {
+            ctrl_ok = false;
+            break;
+          }
         }
       }
-      assert(ctrl_ok, "bad control");
-#endif
+      if (ctrl_ok) {
+        // move the Store
+        _igvn.replace_input_of(mem, LoopNode::LoopBackControl, mem);
+        _igvn.replace_input_of(n, 0, n_loop->_head->in(LoopNode::EntryControl));
+        _igvn.replace_input_of(n, MemNode::Memory, mem->in(LoopNode::EntryControl));
+        // Disconnect the phi now. An empty phi can confuse other
+        // optimizations in this pass of loop opts.
+        _igvn.replace_node(mem, mem->in(LoopNode::EntryControl));
+        n_loop->_body.yank(mem);
 
-      // move the Store
-      _igvn.replace_input_of(mem, LoopNode::LoopBackControl, mem);
-      _igvn.replace_input_of(n, 0, n_loop->_head->in(LoopNode::EntryControl));
-      _igvn.replace_input_of(n, MemNode::Memory, mem->in(LoopNode::EntryControl));
-      // Disconnect the phi now. An empty phi can confuse other
-      // optimizations in this pass of loop opts.
-      _igvn.replace_node(mem, mem->in(LoopNode::EntryControl));
-      n_loop->_body.yank(mem);
+        IdealLoopTree* new_loop = get_loop(n->in(0));
+        set_ctrl_and_loop(n, n->in(0));
 
-      IdealLoopTree* new_loop = get_loop(n->in(0));
-      set_ctrl_and_loop(n, n->in(0));
-
-      return n;
+        return n;
+      }
     }
   }
   return NULL;

--- a/hotspot/test/compiler/TestMoveStoresOutOfLoopsStoreNoCtrl.java	Tue Sep 15 12:59:51 2015 +0000
+++ /dev/null	Thu Jan 01 00:00:00 1970 +0000
@@ -1,49 +0,0 @@
-/*
- * Copyright (c) 2015, Oracle and/or its affiliates. All rights reserved.
- * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
- *
- * This code is free software; you can redistribute it and/or modify it
- * under the terms of the GNU General Public License version 2 only, as
- * published by the Free Software Foundation.
- *
- * This code is distributed in the hope that it will be useful, but WITHOUT
- * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
- * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
- * version 2 for more details (a copy is included in the LICENSE file that
- * accompanied this code).
- *
- * You should have received a copy of the GNU General Public License version
- * 2 along with this work; if not, write to the Free Software Foundation,
- * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
- *
- * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
- * or visit www.oracle.com if you need additional information or have any
- * questions.
- */
-
-/*
- * @test
- * @bug 8134288
- * @summary Store nodes may not have a control if used to update profiling
- * @run main/othervm -XX:-ProfileInterpreter -XX:-TieredCompilation -XX:-BackgroundCompilation TestMoveStoresOutOfLoopsStoreNoCtrl
- *
- */
-
-public class TestMoveStoresOutOfLoopsStoreNoCtrl {
-
-    static void test(boolean flag) {
-        for (int i = 0; i < 20000; i++) {
-            if (flag) {
-                int j = 0;
-                do {
-                    j++;
-                } while(j < 10);
-            }
-        }
-    }
-
-    static public void main(String[] args) {
-        test(false);
-    }
-
-}

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/hotspot/test/compiler/loopopts/TestMoveStoresOutOfLoopsStoreNoCtrl.java	Tue Sep 15 13:08:43 2015 +0200
@@ -0,0 +1,49 @@
+/*
+ * Copyright (c) 2015, Oracle and/or its affiliates. All rights reserved.
+ * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
+ *
+ * This code is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 only, as
+ * published by the Free Software Foundation.
+ *
+ * This code is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+ * version 2 for more details (a copy is included in the LICENSE file that
+ * accompanied this code).
+ *
+ * You should have received a copy of the GNU General Public License version
+ * 2 along with this work; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
+ * or visit www.oracle.com if you need additional information or have any
+ * questions.
+ */
+
+/*
+ * @test
+ * @bug 8134288
+ * @summary Store nodes may not have a control if used to update profiling
+ * @run main/othervm -XX:-ProfileInterpreter -XX:-TieredCompilation -XX:-BackgroundCompilation TestMoveStoresOutOfLoopsStoreNoCtrl
+ *
+ */
+
+public class TestMoveStoresOutOfLoopsStoreNoCtrl {
+
+    static void test(boolean flag) {
+        for (int i = 0; i < 20000; i++) {
+            if (flag) {
+                int j = 0;
+                do {
+                    j++;
+                } while(j < 10);
+            }
+        }
+    }
+
+    static public void main(String[] args) {
+        test(false);
+    }
+
+}