src/hotspot/share/opto/phaseX.cpp

*** 428,451 ****
    // Remove all useless nodes from future worklist
    worklist->remove_useless_nodes(_useful.member_set());
  
    // Disconnect 'useless' nodes that are adjacent to useful nodes
    C->remove_useless_nodes(_useful);
- 
-   // Remove edges from "root" to each SafePoint at a backward branch.
-   // They were inserted during parsing (see add_safepoint()) to make infinite
-   // loops without calls or exceptions visible to root, i.e., useful.
-   Node *root = C->root();
-   if( root != NULL ) {
-     for( uint i = root->req(); i < root->len(); ++i ) {
-       Node *n = root->in(i);
-       if( n != NULL && n->is_SafePoint() ) {
-         root->rm_prec(i);
-         --i;
-       }
-     }
-   }
  }
  
  //=============================================================================
  //------------------------------PhaseRenumberLive------------------------------
  // First, remove useless nodes (equivalent to identifying live nodes).
--- 428,437 ----
*** 1352,1361 ****
--- 1338,1350 ----
    assert(_stack.is_empty(), "not empty");
    _stack.push(dead, PROCESS_INPUTS);
  
    while (_stack.is_nonempty()) {
      dead = _stack.node();
+     if (dead->Opcode() == Op_SafePoint) {
+       dead->as_SafePoint()->disconnect_from_root(this);
+     }
      uint progress_state = _stack.index();
      assert(dead != C->root(), "killing root, eh?");
      assert(!dead->is_top(), "add check for top when pushing");
      NOT_PRODUCT( set_progress(); )
      if (progress_state == PROCESS_INPUTS) {
*** 1454,1463 ****
--- 1443,1455 ----
  }
  
  //------------------------------subsume_node-----------------------------------
  // Remove users from node 'old' and add them to node 'nn'.
  void PhaseIterGVN::subsume_node( Node *old, Node *nn ) {
+   if (old->Opcode() == Op_SafePoint) {
+     old->as_SafePoint()->disconnect_from_root(this);
+   }
    assert( old != hash_find(old), "should already been removed" );
    assert( old != C->top(), "cannot subsume top node");
    // Copy debug or profile information to the new version:
    C->copy_node_notes_to(nn, old);
    // Move users of node 'old' to node 'nn'