393     if (*p != NULL)  (*p)->del_out((Node *)this);
 394     (*p) = n;
 395     if (n != NULL)      n->add_out((Node *)this);
 396   }
 397   // Light version of set_req() to init inputs after node creation.
 398   void init_req( uint i, Node *n ) {
 399     assert( i == 0 && this == n ||
 400             is_not_dead(n), "can not use dead node");
 401     assert( i < _cnt, "oob");
 402     assert( !VerifyHashTableKeys || _hash_lock == 0,
 403             "remove node from hash table before modifying it");
 404     assert( _in[i] == NULL, "sanity");
 405     _in[i] = n;
 406     if (n != NULL)      n->add_out((Node *)this);
 407   }
 408   // Find first occurrence of n among my edges:
 409   int find_edge(Node* n);
 410   int replace_edge(Node* old, Node* neww);
 411   // NULL out all inputs to eliminate incoming Def-Use edges.
 412   // Return the number of edges between 'n' and 'this'
 413   int  disconnect_inputs(Node *n);
 414 
 415   // Quickly, return true if and only if I am Compile::current()->top().
 416   bool is_top() const {
 417     assert((this == (Node*) Compile::current()->top()) == (_out == NULL), "");
 418     return (_out == NULL);
 419   }
 420   // Reaffirm invariants for is_top.  (Only from Compile::set_cached_top_node.)
 421   void setup_is_top();
 422 
 423   // Strip away casting.  (It is depth-limited.)
 424   Node* uncast() const;
 425   // Return whether two Nodes are equivalent, after stripping casting.
 426   bool eqv_uncast(const Node* n) const {
 427     return (this->uncast() == n->uncast());
 428   }
 429 
 430 private:
 431   static Node* uncast_helper(const Node* n);
 432 
 433   // Add an output edge to the end of the list

 441     if (is_top())  return;
 442     Node** outp = &_out[_outcnt];
 443     // Find and remove n
 444     do {
 445       assert(outp > _out, "Missing Def-Use edge");
 446     } while (*--outp != n);
 447     *outp = _out[--_outcnt];
 448     // Smash the old edge so it can't be used accidentally.
 449     debug_only(_out[_outcnt] = (Node *)(uintptr_t)0xdeadbeef);
 450     // Record that a change happened here.
 451     #if OPTO_DU_ITERATOR_ASSERT
 452     debug_only(_last_del = n; ++_del_tick);
 453     #endif
 454   }
 455 
 456 public:
 457   // Globally replace this node by a given new node, updating all uses.
 458   void replace_by(Node* new_node);
 459   // Globally replace this node by a given new node, updating all uses
 460   // and cutting input edges of old node.
 461   void subsume_by(Node* new_node) {
 462     replace_by(new_node);
 463     disconnect_inputs(NULL);
 464   }
 465   void set_req_X( uint i, Node *n, PhaseIterGVN *igvn );
 466   // Find the one non-null required input.  RegionNode only
 467   Node *nonnull_req() const;
 468   // Add or remove precedence edges
 469   void add_prec( Node *n );
 470   void rm_prec( uint i );
 471   void set_prec( uint i, Node *n ) {
 472     assert( is_not_dead(n), "can not use dead node");
 473     assert( i >= _cnt, "not a precedence edge");
 474     if (_in[i] != NULL) _in[i]->del_out((Node *)this);
 475     _in[i] = n;
 476     if (n != NULL) n->add_out((Node *)this);
 477   }
 478   // Set this node's index, used by cisc_version to replace current node
 479   void set_idx(uint new_idx) {
 480     const node_idx_t* ref = &_idx;
 481     *(node_idx_t*)ref = new_idx;
 482   }
 483   // Swap input edge order.  (Edge indexes i1 and i2 are usually 1 and 2.)

 393     if (*p != NULL)  (*p)->del_out((Node *)this);
 394     (*p) = n;
 395     if (n != NULL)      n->add_out((Node *)this);
 396   }
 397   // Light version of set_req() to init inputs after node creation.
 398   void init_req( uint i, Node *n ) {
 399     assert( i == 0 && this == n ||
 400             is_not_dead(n), "can not use dead node");
 401     assert( i < _cnt, "oob");
 402     assert( !VerifyHashTableKeys || _hash_lock == 0,
 403             "remove node from hash table before modifying it");
 404     assert( _in[i] == NULL, "sanity");
 405     _in[i] = n;
 406     if (n != NULL)      n->add_out((Node *)this);
 407   }
 408   // Find first occurrence of n among my edges:
 409   int find_edge(Node* n);
 410   int replace_edge(Node* old, Node* neww);
 411   // NULL out all inputs to eliminate incoming Def-Use edges.
 412   // Return the number of edges between 'n' and 'this'
 413   int  disconnect_inputs(Node *n, Compile *c);
 414 
 415   // Quickly, return true if and only if I am Compile::current()->top().
 416   bool is_top() const {
 417     assert((this == (Node*) Compile::current()->top()) == (_out == NULL), "");
 418     return (_out == NULL);
 419   }
 420   // Reaffirm invariants for is_top.  (Only from Compile::set_cached_top_node.)
 421   void setup_is_top();
 422 
 423   // Strip away casting.  (It is depth-limited.)
 424   Node* uncast() const;
 425   // Return whether two Nodes are equivalent, after stripping casting.
 426   bool eqv_uncast(const Node* n) const {
 427     return (this->uncast() == n->uncast());
 428   }
 429 
 430 private:
 431   static Node* uncast_helper(const Node* n);
 432 
 433   // Add an output edge to the end of the list

 441     if (is_top())  return;
 442     Node** outp = &_out[_outcnt];
 443     // Find and remove n
 444     do {
 445       assert(outp > _out, "Missing Def-Use edge");
 446     } while (*--outp != n);
 447     *outp = _out[--_outcnt];
 448     // Smash the old edge so it can't be used accidentally.
 449     debug_only(_out[_outcnt] = (Node *)(uintptr_t)0xdeadbeef);
 450     // Record that a change happened here.
 451     #if OPTO_DU_ITERATOR_ASSERT
 452     debug_only(_last_del = n; ++_del_tick);
 453     #endif
 454   }
 455 
 456 public:
 457   // Globally replace this node by a given new node, updating all uses.
 458   void replace_by(Node* new_node);
 459   // Globally replace this node by a given new node, updating all uses
 460   // and cutting input edges of old node.
 461   void subsume_by(Node* new_node, Compile* c) {
 462     replace_by(new_node);
 463     disconnect_inputs(NULL, c);
 464   }
 465   void set_req_X( uint i, Node *n, PhaseIterGVN *igvn );
 466   // Find the one non-null required input.  RegionNode only
 467   Node *nonnull_req() const;
 468   // Add or remove precedence edges
 469   void add_prec( Node *n );
 470   void rm_prec( uint i );
 471   void set_prec( uint i, Node *n ) {
 472     assert( is_not_dead(n), "can not use dead node");
 473     assert( i >= _cnt, "not a precedence edge");
 474     if (_in[i] != NULL) _in[i]->del_out((Node *)this);
 475     _in[i] = n;
 476     if (n != NULL) n->add_out((Node *)this);
 477   }
 478   // Set this node's index, used by cisc_version to replace current node
 479   void set_idx(uint new_idx) {
 480     const node_idx_t* ref = &_idx;
 481     *(node_idx_t*)ref = new_idx;
 482   }
 483   // Swap input edge order.  (Edge indexes i1 and i2 are usually 1 and 2.)