--- a/hotspot/src/share/vm/opto/callnode.cpp	Sat Jan 07 13:26:43 2012 -0800
+++ b/hotspot/src/share/vm/opto/callnode.cpp	Tue Jan 10 18:05:38 2012 -0800
@@ -1386,7 +1386,7 @@
     Node *n = ctrl_proj->in(0);
     if (n != NULL && n->is_Unlock()) {
       UnlockNode *unlock = n->as_Unlock();
-      if ((lock->obj_node() == unlock->obj_node()) &&
+      if (lock->obj_node()->eqv_uncast(unlock->obj_node()) &&
           BoxLockNode::same_slot(lock->box_node(), unlock->box_node()) &&
           !unlock->is_eliminated()) {
         lock_ops.append(unlock);
@@ -1431,7 +1431,7 @@
   }
   if (ctrl->is_Lock()) {
     LockNode *lock = ctrl->as_Lock();
-    if ((lock->obj_node() == unlock->obj_node()) &&
+    if (lock->obj_node()->eqv_uncast(unlock->obj_node()) &&
         BoxLockNode::same_slot(lock->box_node(), unlock->box_node())) {
       lock_result = lock;
     }
@@ -1462,7 +1462,7 @@
       }
       if (lock1_node != NULL && lock1_node->is_Lock()) {
         LockNode *lock1 = lock1_node->as_Lock();
-        if ((lock->obj_node() == lock1->obj_node()) &&
+        if (lock->obj_node()->eqv_uncast(lock1->obj_node()) &&
             BoxLockNode::same_slot(lock->box_node(), lock1->box_node()) &&
             !lock1->is_eliminated()) {
           lock_ops.append(lock1);
@@ -1650,7 +1650,7 @@
     for (int idx = 0; idx < num_mon; idx++) {
       Node* obj_node = sfn->monitor_obj(jvms, idx);
       BoxLockNode* box_node = BoxLockNode::box_node(sfn->monitor_box(jvms, idx));
-      if ((obj_node == obj) && (box_node->stack_slot() < stk_slot)) {
+      if ((box_node->stack_slot() < stk_slot) && obj_node->eqv_uncast(obj)) {
         return true;
       }
     }

--- a/hotspot/src/share/vm/opto/cfgnode.cpp	Sat Jan 07 13:26:43 2012 -0800
+++ b/hotspot/src/share/vm/opto/cfgnode.cpp	Tue Jan 10 18:05:38 2012 -0800
@@ -1597,7 +1597,7 @@
       bool is_loop = (r->is_Loop() && r->req() == 3);
       // Then, check if there is a data loop when phi references itself directly
       // or through other data nodes.
-      if (is_loop && !phase->eqv_uncast(uin, in(LoopNode::EntryControl)) ||
+      if (is_loop && !uin->eqv_uncast(in(LoopNode::EntryControl)) ||
          !is_loop && is_unsafe_data_reference(uin)) {
         // Break this data loop to avoid creation of a dead loop.
         if (can_reshape) {

--- a/hotspot/src/share/vm/opto/library_call.cpp	Sat Jan 07 13:26:43 2012 -0800
+++ b/hotspot/src/share/vm/opto/library_call.cpp	Tue Jan 10 18:05:38 2012 -0800
@@ -819,7 +819,7 @@
   if (stopped())
     return NULL;                // already stopped
   bool zero_offset = _gvn.type(offset) == TypeInt::ZERO;
-  if (zero_offset && _gvn.eqv_uncast(subseq_length, array_length))
+  if (zero_offset && subseq_length->eqv_uncast(array_length))
     return NULL;                // common case of whole-array copy
   Node* last = subseq_length;
   if (!zero_offset)             // last += offset
@@ -4667,7 +4667,7 @@
   if (ReduceBulkZeroing
       && !ZeroTLAB              // pointless if already zeroed
       && basic_elem_type != T_CONFLICT // avoid corner case
-      && !_gvn.eqv_uncast(src, dest)
+      && !src->eqv_uncast(dest)
       && ((alloc = tightly_coupled_allocation(dest, slow_region))
           != NULL)
       && _gvn.find_int_con(alloc->in(AllocateNode::ALength), 1) > 0
@@ -4745,7 +4745,7 @@
     // copy_length is 0.
     if (!stopped() && dest_uninitialized) {
       Node* dest_length = alloc->in(AllocateNode::ALength);
-      if (_gvn.eqv_uncast(copy_length, dest_length)
+      if (copy_length->eqv_uncast(dest_length)
           || _gvn.find_int_con(dest_length, 1) <= 0) {
         // There is no zeroing to do. No need for a secondary raw memory barrier.
       } else {
@@ -4791,7 +4791,7 @@
     // with its attendant messy index arithmetic, and upgrade
     // the copy to a more hardware-friendly word size of 64 bits.
     Node* tail_ctl = NULL;
-    if (!stopped() && !_gvn.eqv_uncast(dest_tail, dest_length)) {
+    if (!stopped() && !dest_tail->eqv_uncast(dest_length)) {
       Node* cmp_lt   = _gvn.transform( new(C,3) CmpINode(dest_tail, dest_length) );
       Node* bol_lt   = _gvn.transform( new(C,2) BoolNode(cmp_lt, BoolTest::lt) );
       tail_ctl = generate_slow_guard(bol_lt, NULL);

--- a/hotspot/src/share/vm/opto/locknode.cpp	Sat Jan 07 13:26:43 2012 -0800
+++ b/hotspot/src/share/vm/opto/locknode.cpp	Tue Jan 10 18:05:38 2012 -0800
@@ -100,7 +100,7 @@
       AbstractLockNode* alock = n->as_AbstractLock();
       // Check lock's box since box could be referenced by Lock's debug info.
       if (alock->box_node() == this) {
-        if (alock->obj_node() == obj) {
+        if (alock->obj_node()->eqv_uncast(obj)) {
           if ((unique_lock != NULL) && alock->is_Lock()) {
             if (lock == NULL) {
               lock = alock->as_Lock();
@@ -121,7 +121,7 @@
     Node* n = this->raw_out(i);
     if (n->is_FastLock()) {
       FastLockNode* flock = n->as_FastLock();
-      assert((flock->box_node() == this) && (flock->obj_node() == obj),"");
+      assert((flock->box_node() == this) && flock->obj_node()->eqv_uncast(obj),"");
     }
     if (n->is_SafePoint() && n->as_SafePoint()->jvms()) {
       SafePointNode* sfn = n->as_SafePoint();
@@ -135,7 +135,7 @@
           Node* obj_node = sfn->monitor_obj(jvms, idx);
           Node* box_node = sfn->monitor_box(jvms, idx);
           if (box_node == this) {
-            assert(obj_node == obj,"");
+            assert(obj_node->eqv_uncast(obj),"");
           }
         }
       }

--- a/hotspot/src/share/vm/opto/macro.cpp	Sat Jan 07 13:26:43 2012 -0800
+++ b/hotspot/src/share/vm/opto/macro.cpp	Tue Jan 10 18:05:38 2012 -0800
@@ -1818,7 +1818,7 @@
         AbstractLockNode* alock = u->as_AbstractLock();
         // Check lock's box since box could be referenced by Lock's debug info.
         if (alock->box_node() == oldbox) {
-          assert(alock->obj_node() == obj, "");
+          assert(alock->obj_node()->eqv_uncast(obj), "");
           // Mark eliminated all related locks and unlocks.
           alock->set_non_esc_obj();
         }
@@ -1845,7 +1845,7 @@
     Node* u = oldbox->raw_out(i);
     if (u->is_AbstractLock()) {
       AbstractLockNode* alock = u->as_AbstractLock();
-      if (alock->obj_node() == obj && alock->box_node() == oldbox) {
+      if (alock->box_node() == oldbox && alock->obj_node()->eqv_uncast(obj)) {
         // Replace Box and mark eliminated all related locks and unlocks.
         alock->set_non_esc_obj();
         _igvn.hash_delete(alock);
@@ -1854,7 +1854,7 @@
         next_edge = false;
       }
     }
-    if (u->is_FastLock() && u->as_FastLock()->obj_node() == obj) {
+    if (u->is_FastLock() && u->as_FastLock()->obj_node()->eqv_uncast(obj)) {
       FastLockNode* flock = u->as_FastLock();
       assert(flock->box_node() == oldbox, "sanity");
       _igvn.hash_delete(flock);
@@ -1875,7 +1875,7 @@
         for (int idx = 0; idx < num_mon; idx++) {
           Node* obj_node = sfn->monitor_obj(jvms, idx);
           Node* box_node = sfn->monitor_box(jvms, idx);
-          if (box_node == oldbox && obj_node == obj) {
+          if (box_node == oldbox && obj_node->eqv_uncast(obj)) {
             int j = jvms->monitor_box_offset(idx);
             _igvn.hash_delete(u);
             u->set_req(j, newbox);
@@ -1912,7 +1912,7 @@
             alock = u->as_AbstractLock();
             if (alock->box_node() == box_node) {
               // Verify that this Box is referenced only by related locks.
-              assert(alock->obj_node() == obj, "");
+              assert(alock->obj_node()->eqv_uncast(obj), "");
               // Mark all related locks and unlocks.
               alock->set_nested();
             }
@@ -1931,7 +1931,8 @@
     Node* obj = alock->obj_node();
     for (uint j = 0; j < obj->outcnt(); j++) {
       Node* o = obj->raw_out(j);
-      if (o->is_AbstractLock() && o->as_AbstractLock()->obj_node() == obj) {
+      if (o->is_AbstractLock() &&
+          o->as_AbstractLock()->obj_node()->eqv_uncast(obj)) {
         alock = o->as_AbstractLock();
         Node* box = alock->box_node();
         // Replace old box node with new eliminated box for all users

--- a/hotspot/src/share/vm/opto/memnode.cpp	Sat Jan 07 13:26:43 2012 -0800
+++ b/hotspot/src/share/vm/opto/memnode.cpp	Tue Jan 10 18:05:38 2012 -0800
@@ -2201,7 +2201,7 @@
   // unsafe if I have intervening uses...  Also disallowed for StoreCM
   // since they must follow each StoreP operation.  Redundant StoreCMs
   // are eliminated just before matching in final_graph_reshape.
-  if (mem->is_Store() && phase->eqv_uncast(mem->in(MemNode::Address), address) &&
+  if (mem->is_Store() && mem->in(MemNode::Address)->eqv_uncast(address) &&
       mem->Opcode() != Op_StoreCM) {
     // Looking at a dead closed cycle of memory?
     assert(mem != mem->in(MemNode::Memory), "dead loop in StoreNode::Ideal");
@@ -2274,16 +2274,16 @@
 
   // Load then Store?  Then the Store is useless
   if (val->is_Load() &&
-      phase->eqv_uncast( val->in(MemNode::Address), adr ) &&
-      phase->eqv_uncast( val->in(MemNode::Memory ), mem ) &&
+      val->in(MemNode::Address)->eqv_uncast(adr) &&
+      val->in(MemNode::Memory )->eqv_uncast(mem) &&
       val->as_Load()->store_Opcode() == Opcode()) {
     return mem;
   }
 
   // Two stores in a row of the same value?
   if (mem->is_Store() &&
-      phase->eqv_uncast( mem->in(MemNode::Address), adr ) &&
-      phase->eqv_uncast( mem->in(MemNode::ValueIn), val ) &&
+      mem->in(MemNode::Address)->eqv_uncast(adr) &&
+      mem->in(MemNode::ValueIn)->eqv_uncast(val) &&
       mem->Opcode() == Opcode()) {
     return mem;
   }

--- a/hotspot/src/share/vm/opto/node.cpp	Sat Jan 07 13:26:43 2012 -0800
+++ b/hotspot/src/share/vm/opto/node.cpp	Tue Jan 10 18:05:38 2012 -0800
@@ -833,8 +833,20 @@
 
 //---------------------------uncast_helper-------------------------------------
 Node* Node::uncast_helper(const Node* p) {
-  uint max_depth = 3;
-  for (uint i = 0; i < max_depth; i++) {
+#ifdef ASSERT
+  uint depth_count = 0;
+  const Node* orig_p = p;
+#endif
+
+  while (true) {
+#ifdef ASSERT
+    if (depth_count >= K) {
+      orig_p->dump(4);
+      if (p != orig_p)
+        p->dump(1);
+    }
+    assert(depth_count++ < K, "infinite loop in Node::uncast_helper");
+#endif
     if (p == NULL || p->req() != 2) {
       break;
     } else if (p->is_ConstraintCast()) {

--- a/hotspot/src/share/vm/opto/node.hpp	Sat Jan 07 13:26:43 2012 -0800
+++ b/hotspot/src/share/vm/opto/node.hpp	Tue Jan 10 18:05:38 2012 -0800
@@ -429,6 +429,10 @@
 
   // Strip away casting.  (It is depth-limited.)
   Node* uncast() const;
+  // Return whether two Nodes are equivalent, after stripping casting.
+  bool eqv_uncast(const Node* n) const {
+    return (this->uncast() == n->uncast());
+  }
 
 private:
   static Node* uncast_helper(const Node* n);

--- a/hotspot/src/share/vm/opto/phaseX.hpp	Sat Jan 07 13:26:43 2012 -0800
+++ b/hotspot/src/share/vm/opto/phaseX.hpp	Tue Jan 10 18:05:38 2012 -0800
@@ -256,11 +256,6 @@
   // For pessimistic optimizations this is simply pointer equivalence.
   bool eqv(const Node* n1, const Node* n2) const { return n1 == n2; }
 
-  // Return whether two Nodes are equivalent, after stripping casting.
-  bool eqv_uncast(const Node* n1, const Node* n2) const {
-    return eqv(n1->uncast(), n2->uncast());
-  }
-
   // For pessimistic passes, the return type must monotonically narrow.
   // For optimistic  passes, the return type must monotonically widen.
   // It is possible to get into a "death march" in either type of pass,

--- a/hotspot/src/share/vm/opto/subnode.cpp	Sat Jan 07 13:26:43 2012 -0800
+++ b/hotspot/src/share/vm/opto/subnode.cpp	Tue Jan 10 18:05:38 2012 -0800
@@ -91,7 +91,7 @@
 
   // Not correct for SubFnode and AddFNode (must check for infinity)
   // Equal?  Subtract is zero
-  if (phase->eqv_uncast(in1, in2))  return add_id();
+  if (in1->eqv_uncast(in2))  return add_id();
 
   // Either input is BOTTOM ==> the result is the local BOTTOM
   if( t1 == Type::BOTTOM || t2 == Type::BOTTOM )

--- a/hotspot/test/compiler/7116216/StackOverflow.java	Sat Jan 07 13:26:43 2012 -0800
+++ b/hotspot/test/compiler/7116216/StackOverflow.java	Tue Jan 10 18:05:38 2012 -0800
@@ -30,7 +30,7 @@
  * @run main/othervm -Xcomp -Xbatch StackOverflow
  */
 
-class StackOverflow {
+public class StackOverflow {
     static String stackOverflow_largeFrame_liveOopForGC;
 
     public static int stackOverflow_largeFrame(int call_count, String liveOopForGC) {