277   // are required, from _cnt to _max-1 are precedence edges.
 278   node_idx_t _cnt;              // Total number of required Node inputs.
 279 
 280   node_idx_t _max;              // Actual length of input array.
 281 
 282   // Output edges are an unordered list of def-use edges which exactly
 283   // correspond to required input edges which point from other nodes
 284   // to this one.  Thus the count of the output edges is the number of
 285   // users of this node.
 286   node_idx_t _outcnt;           // Total number of Node outputs.
 287 
 288   node_idx_t _outmax;           // Actual length of output array.
 289 
 290   // Grow the actual input array to the next larger power-of-2 bigger than len.
 291   void grow( uint len );
 292   // Grow the output array to the next larger power-of-2 bigger than len.
 293   void out_grow( uint len );
 294 
 295  public:
 296   // Each Node is assigned a unique small/dense number.  This number is used
 297   // to index into auxiliary arrays of data and bitvectors.
 298   // It is declared const to defend against inadvertant assignment,
 299   // since it is used by clients as a naked field.





 300   const node_idx_t _idx;

 301 
 302   // Get the (read-only) number of input edges
 303   uint req() const { return _cnt; }
 304   uint len() const { return _max; }
 305   // Get the (read-only) number of output edges
 306   uint outcnt() const { return _outcnt; }
 307 
 308 #if OPTO_DU_ITERATOR_ASSERT
 309   // Iterate over the out-edges of this node.  Deletions are illegal.
 310   inline DUIterator outs() const;
 311   // Use this when the out array might have changed to suppress asserts.
 312   inline DUIterator& refresh_out_pos(DUIterator& i) const;
 313   // Does the node have an out at this position?  (Used for iteration.)
 314   inline bool has_out(DUIterator& i) const;
 315   inline Node*    out(DUIterator& i) const;
 316   // Iterate over the out-edges of this node.  All changes are illegal.
 317   inline DUIterator_Fast fast_outs(DUIterator_Fast& max) const;
 318   inline Node*    fast_out(DUIterator_Fast& i) const;
 319   // Iterate over the out-edges of this node, deleting one at a time.
 320   inline DUIterator_Last last_outs(DUIterator_Last& min) const;

 277   // are required, from _cnt to _max-1 are precedence edges.
 278   node_idx_t _cnt;              // Total number of required Node inputs.
 279 
 280   node_idx_t _max;              // Actual length of input array.
 281 
 282   // Output edges are an unordered list of def-use edges which exactly
 283   // correspond to required input edges which point from other nodes
 284   // to this one.  Thus the count of the output edges is the number of
 285   // users of this node.
 286   node_idx_t _outcnt;           // Total number of Node outputs.
 287 
 288   node_idx_t _outmax;           // Actual length of output array.
 289 
 290   // Grow the actual input array to the next larger power-of-2 bigger than len.
 291   void grow( uint len );
 292   // Grow the output array to the next larger power-of-2 bigger than len.
 293   void out_grow( uint len );
 294 
 295  public:
 296   // Each Node is assigned a unique small/dense number.  This number is used
 297   // to index into auxiliary arrays of data and bit vectors.
 298   // The field _idx is declared constant to defend against inadvertent assignments,
 299   // since it is used by clients as a naked field. However, the field's value can be
 300   // changed using the set_idx() method.
 301   //
 302   // The PhaseRenumberLive phase renumbers nodes based on liveness information.
 303   // Therefore, it updates the value of the _idx field. The parse-time _idx is
 304   // preserved in _parse_idx.
 305   const node_idx_t _idx;
 306   DEBUG_ONLY(const node_idx_t _parse_idx;)
 307 
 308   // Get the (read-only) number of input edges
 309   uint req() const { return _cnt; }
 310   uint len() const { return _max; }
 311   // Get the (read-only) number of output edges
 312   uint outcnt() const { return _outcnt; }
 313 
 314 #if OPTO_DU_ITERATOR_ASSERT
 315   // Iterate over the out-edges of this node.  Deletions are illegal.
 316   inline DUIterator outs() const;
 317   // Use this when the out array might have changed to suppress asserts.
 318   inline DUIterator& refresh_out_pos(DUIterator& i) const;
 319   // Does the node have an out at this position?  (Used for iteration.)
 320   inline bool has_out(DUIterator& i) const;
 321   inline Node*    out(DUIterator& i) const;
 322   // Iterate over the out-edges of this node.  All changes are illegal.
 323   inline DUIterator_Fast fast_outs(DUIterator_Fast& max) const;
 324   inline Node*    fast_out(DUIterator_Fast& i) const;
 325   // Iterate over the out-edges of this node, deleting one at a time.
 326   inline DUIterator_Last last_outs(DUIterator_Last& min) const;