hotspot/src/share/vm/opto/escape.hpp
changeset 12158 f24f2560da32
parent 11198 34c860ff41e3
child 13391 30245956af37
equal deleted inserted replaced
12112:56e3093129dc 12158:f24f2560da32
     1 /*
     1 /*
     2  * Copyright (c) 2005, 2011, Oracle and/or its affiliates. All rights reserved.
     2  * Copyright (c) 2005, 2012, Oracle and/or its affiliates. All rights reserved.
     3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
     3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
     4  *
     4  *
     5  * This code is free software; you can redistribute it and/or modify it
     5  * This code is free software; you can redistribute it and/or modify it
     6  * under the terms of the GNU General Public License version 2 only, as
     6  * under the terms of the GNU General Public License version 2 only, as
     7  * published by the Free Software Foundation.
     7  * published by the Free Software Foundation.
   113 class  Compile;
   113 class  Compile;
   114 class  Node;
   114 class  Node;
   115 class  CallNode;
   115 class  CallNode;
   116 class  PhiNode;
   116 class  PhiNode;
   117 class  PhaseTransform;
   117 class  PhaseTransform;
       
   118 class  PointsToNode;
   118 class  Type;
   119 class  Type;
   119 class  TypePtr;
   120 class  TypePtr;
   120 class  VectorSet;
   121 class  VectorSet;
   121 
   122 
   122 class PointsToNode {
   123 class JavaObjectNode;
   123 friend class ConnectionGraph;
   124 class LocalVarNode;
       
   125 class FieldNode;
       
   126 class ArraycopyNode;
       
   127 
       
   128 // ConnectionGraph nodes
       
   129 class PointsToNode : public ResourceObj {
       
   130   GrowableArray<PointsToNode*> _edges; // List of nodes this node points to
       
   131   GrowableArray<PointsToNode*> _uses;  // List of nodes which point to this node
       
   132 
       
   133   const u1           _type;  // NodeType
       
   134   u1                _flags;  // NodeFlags
       
   135   u1               _escape;  // EscapeState of object
       
   136   u1        _fields_escape;  // EscapeState of object's fields
       
   137 
       
   138   Node* const        _node;  // Ideal node corresponding to this PointsTo node.
       
   139   const int           _idx;  // Cached ideal node's _idx
       
   140 
   124 public:
   141 public:
   125   typedef enum {
   142   typedef enum {
   126     UnknownType = 0,
   143     UnknownType = 0,
   127     JavaObject  = 1,
   144     JavaObject  = 1,
   128     LocalVar    = 2,
   145     LocalVar    = 2,
   129     Field       = 3
   146     Field       = 3,
       
   147     Arraycopy   = 4
   130   } NodeType;
   148   } NodeType;
   131 
   149 
   132   typedef enum {
   150   typedef enum {
   133     UnknownEscape = 0,
   151     UnknownEscape = 0,
   134     NoEscape      = 1, // An object does not escape method or thread and it is
   152     NoEscape      = 1, // An object does not escape method or thread and it is
   138                        // and it does not escape during call.
   156                        // and it does not escape during call.
   139     GlobalEscape  = 3  // An object escapes the method or thread.
   157     GlobalEscape  = 3  // An object escapes the method or thread.
   140   } EscapeState;
   158   } EscapeState;
   141 
   159 
   142   typedef enum {
   160   typedef enum {
   143     UnknownEdge   = 0,
   161     ScalarReplaceable = 1,  // Not escaped object could be replaced with scalar
   144     PointsToEdge  = 1,
   162     PointsToUnknown   = 2,  // Has edge to phantom_object
   145     DeferredEdge  = 2,
   163     ArraycopySrc      = 4,  // Has edge from Arraycopy node
   146     FieldEdge     = 3
   164     ArraycopyDst      = 8   // Has edge to Arraycopy node
   147   } EdgeType;
   165   } NodeFlags;
   148 
   166 
   149 private:
   167 
   150   enum {
   168   PointsToNode(Compile *C, Node* n, EscapeState es, NodeType type):
   151     EdgeMask = 3,
   169     _edges(C->comp_arena(), 2, 0, NULL),
   152     EdgeShift = 2,
   170     _uses (C->comp_arena(), 2, 0, NULL),
   153 
   171     _node(n),
   154     INITIAL_EDGE_COUNT = 4
   172     _idx(n->_idx),
   155   };
   173     _type((u1)type),
   156 
   174     _escape((u1)es),
   157   NodeType             _type;
   175     _fields_escape((u1)es),
   158   EscapeState          _escape;
   176     _flags(ScalarReplaceable) {
   159   GrowableArray<uint>* _edges; // outgoing edges
   177     assert(n != NULL && es != UnknownEscape, "sanity");
   160   Node* _node;                 // Ideal node corresponding to this PointsTo node.
   178   }
   161   int   _offset;               // Object fields offsets.
   179 
   162   bool  _scalar_replaceable;   // Not escaped object could be replaced with scalar
   180   Node* ideal_node()   const { return _node; }
   163   bool  _has_unknown_ptr;      // Has edge to phantom_object
   181   int          idx()   const { return _idx; }
   164 
   182 
   165 public:
   183   bool is_JavaObject() const { return _type == (u1)JavaObject; }
   166   PointsToNode():
   184   bool is_LocalVar()   const { return _type == (u1)LocalVar; }
   167     _type(UnknownType),
   185   bool is_Field()      const { return _type == (u1)Field; }
   168     _escape(UnknownEscape),
   186   bool is_Arraycopy()  const { return _type == (u1)Arraycopy; }
   169     _edges(NULL),
   187 
   170     _node(NULL),
   188   JavaObjectNode* as_JavaObject() { assert(is_JavaObject(),""); return (JavaObjectNode*)this; }
   171     _offset(-1),
   189   LocalVarNode*   as_LocalVar()   { assert(is_LocalVar(),"");   return (LocalVarNode*)this; }
   172     _has_unknown_ptr(false),
   190   FieldNode*      as_Field()      { assert(is_Field(),"");      return (FieldNode*)this; }
   173     _scalar_replaceable(true) {}
   191   ArraycopyNode*  as_Arraycopy()  { assert(is_Arraycopy(),"");  return (ArraycopyNode*)this; }
   174 
   192 
   175 
   193   EscapeState escape_state() const { return (EscapeState)_escape; }
   176   EscapeState escape_state() const { return _escape; }
   194   void    set_escape_state(EscapeState state) { _escape = (u1)state; }
   177   NodeType node_type() const { return _type;}
   195 
   178   int offset() { return _offset;}
   196   EscapeState fields_escape_state() const { return (EscapeState)_fields_escape; }
   179   bool scalar_replaceable() { return _scalar_replaceable;}
   197   void    set_fields_escape_state(EscapeState state) { _fields_escape = (u1)state; }
   180   bool has_unknown_ptr()    { return _has_unknown_ptr;}
   198 
   181 
   199   bool     has_unknown_ptr() const { return (_flags & PointsToUnknown) != 0; }
   182   void set_offset(int offs) { _offset = offs;}
   200   void set_has_unknown_ptr()       { _flags |= PointsToUnknown; }
   183   void set_escape_state(EscapeState state) { _escape = state; }
   201 
   184   void set_node_type(NodeType ntype) {
   202   bool     arraycopy_src() const { return (_flags & ArraycopySrc) != 0; }
   185     assert(_type == UnknownType || _type == ntype, "Can't change node type");
   203   void set_arraycopy_src()       { _flags |= ArraycopySrc; }
   186     _type = ntype;
   204   bool     arraycopy_dst() const { return (_flags & ArraycopyDst) != 0; }
   187   }
   205   void set_arraycopy_dst()       { _flags |= ArraycopyDst; }
   188   void set_scalar_replaceable(bool v) { _scalar_replaceable = v; }
   206 
   189   void set_has_unknown_ptr()          { _has_unknown_ptr = true; }
   207   bool     scalar_replaceable() const { return (_flags & ScalarReplaceable) != 0;}
   190 
   208   void set_scalar_replaceable(bool v) {
   191   // count of outgoing edges
   209     if (v)
   192   uint edge_count() const { return (_edges == NULL) ? 0 : _edges->length(); }
   210       _flags |= ScalarReplaceable;
   193 
   211     else
   194   // node index of target of outgoing edge "e"
   212       _flags &= ~ScalarReplaceable;
   195   uint edge_target(uint e) const {
   213   }
   196     assert(_edges != NULL, "valid edge index");
   214 
   197     return (_edges->at(e) >> EdgeShift);
   215   int edge_count()              const { return _edges.length(); }
   198   }
   216   PointsToNode* edge(int e)     const { return _edges.at(e); }
   199   // type of outgoing edge "e"
   217   bool add_edge(PointsToNode* edge)    { return _edges.append_if_missing(edge); }
   200   EdgeType edge_type(uint e) const {
   218 
   201     assert(_edges != NULL, "valid edge index");
   219   int use_count()             const { return _uses.length(); }
   202     return (EdgeType) (_edges->at(e) & EdgeMask);
   220   PointsToNode* use(int e)    const { return _uses.at(e); }
   203   }
   221   bool add_use(PointsToNode* use)    { return _uses.append_if_missing(use); }
   204 
   222 
   205   // add a edge of the specified type pointing to the specified target
   223   // Mark base edge use to distinguish from stored value edge.
   206   void add_edge(uint targIdx, EdgeType et);
   224   bool add_base_use(FieldNode* use) { return _uses.append_if_missing((PointsToNode*)((intptr_t)use + 1)); }
   207 
   225   static bool is_base_use(PointsToNode* use) { return (((intptr_t)use) & 1); }
   208   // remove an edge of the specified type pointing to the specified target
   226   static PointsToNode* get_use_node(PointsToNode* use) { return (PointsToNode*)(((intptr_t)use) & ~1); }
   209   void remove_edge(uint targIdx, EdgeType et);
   227 
       
   228   // Return true if this node points to specified node or nodes it points to.
       
   229   bool points_to(JavaObjectNode* ptn) const;
       
   230 
       
   231   // Return true if this node points only to non-escaping allocations.
       
   232   bool non_escaping_allocation();
       
   233 
       
   234   // Return true if one node points to an other.
       
   235   bool meet(PointsToNode* ptn);
   210 
   236 
   211 #ifndef PRODUCT
   237 #ifndef PRODUCT
       
   238   NodeType node_type() const { return (NodeType)_type;}
   212   void dump(bool print_state=true) const;
   239   void dump(bool print_state=true) const;
   213 #endif
   240 #endif
   214 
   241 
   215 };
   242 };
   216 
   243 
       
   244 class LocalVarNode: public PointsToNode {
       
   245 public:
       
   246   LocalVarNode(Compile *C, Node* n, EscapeState es):
       
   247     PointsToNode(C, n, es, LocalVar) {}
       
   248 };
       
   249 
       
   250 class JavaObjectNode: public PointsToNode {
       
   251 public:
       
   252   JavaObjectNode(Compile *C, Node* n, EscapeState es):
       
   253     PointsToNode(C, n, es, JavaObject) {
       
   254       if (es > NoEscape)
       
   255         set_scalar_replaceable(false);
       
   256     }
       
   257 };
       
   258 
       
   259 class FieldNode: public PointsToNode {
       
   260   GrowableArray<PointsToNode*> _bases; // List of JavaObject nodes which point to this node
       
   261   const int   _offset; // Field's offset.
       
   262   const bool  _is_oop; // Field points to object
       
   263         bool  _has_unknown_base; // Has phantom_object base
       
   264 public:
       
   265   FieldNode(Compile *C, Node* n, EscapeState es, int offs, bool is_oop):
       
   266     PointsToNode(C, n, es, Field),
       
   267     _offset(offs), _is_oop(is_oop),
       
   268     _has_unknown_base(false) {}
       
   269 
       
   270   int      offset()              const { return _offset;}
       
   271   bool     is_oop()              const { return _is_oop;}
       
   272   bool     has_unknown_base()    const { return _has_unknown_base; }
       
   273   void set_has_unknown_base()          { _has_unknown_base = true; }
       
   274 
       
   275   int base_count()              const { return _bases.length(); }
       
   276   PointsToNode* base(int e)     const { return _bases.at(e); }
       
   277   bool add_base(PointsToNode* base)    { return _bases.append_if_missing(base); }
       
   278 #ifdef ASSERT
       
   279   // Return true if bases points to this java object.
       
   280   bool has_base(JavaObjectNode* ptn) const;
       
   281 #endif
       
   282 
       
   283 };
       
   284 
       
   285 class ArraycopyNode: public PointsToNode {
       
   286 public:
       
   287   ArraycopyNode(Compile *C, Node* n, EscapeState es):
       
   288     PointsToNode(C, n, es, Arraycopy) {}
       
   289 };
       
   290 
       
   291 // Iterators for PointsTo node's edges:
       
   292 //   for (EdgeIterator i(n); i.has_next(); i.next()) {
       
   293 //     PointsToNode* u = i.get();
       
   294 class PointsToIterator: public StackObj {
       
   295 protected:
       
   296   const PointsToNode* node;
       
   297   const int cnt;
       
   298   int i;
       
   299 public:
       
   300   inline PointsToIterator(const PointsToNode* n, int cnt) : node(n), cnt(cnt), i(0) { }
       
   301   inline bool has_next() const { return i < cnt; }
       
   302   inline void next() { i++; }
       
   303   PointsToNode* get() const { ShouldNotCallThis(); return NULL; }
       
   304 };
       
   305 
       
   306 class EdgeIterator: public PointsToIterator {
       
   307 public:
       
   308   inline EdgeIterator(const PointsToNode* n) : PointsToIterator(n, n->edge_count()) { }
       
   309   inline PointsToNode* get() const { return node->edge(i); }
       
   310 };
       
   311 
       
   312 class UseIterator: public PointsToIterator {
       
   313 public:
       
   314   inline UseIterator(const PointsToNode* n) : PointsToIterator(n, n->use_count()) { }
       
   315   inline PointsToNode* get() const { return node->use(i); }
       
   316 };
       
   317 
       
   318 class BaseIterator: public PointsToIterator {
       
   319 public:
       
   320   inline BaseIterator(const FieldNode* n) : PointsToIterator(n, n->base_count()) { }
       
   321   inline PointsToNode* get() const { return ((PointsToNode*)node)->as_Field()->base(i); }
       
   322 };
       
   323 
       
   324 
   217 class ConnectionGraph: public ResourceObj {
   325 class ConnectionGraph: public ResourceObj {
   218 private:
   326 private:
   219   GrowableArray<PointsToNode>  _nodes; // Connection graph nodes indexed
   327   GrowableArray<PointsToNode*>  _nodes; // Map from ideal nodes to
   220                                        // by ideal node index.
   328                                         // ConnectionGraph nodes.
   221 
   329 
   222   Unique_Node_List  _delayed_worklist; // Nodes to be processed before
   330   GrowableArray<PointsToNode*>  _worklist; // Nodes to be processed
   223                                        // the call build_connection_graph().
   331 
   224 
   332   bool            _collecting; // Indicates whether escape information
   225   GrowableArray<MergeMemNode *>  _mergemem_worklist; // List of all MergeMem nodes
   333                                // is still being collected. If false,
   226 
   334                                // no new nodes will be processed.
   227   VectorSet                _processed; // Records which nodes have been
   335 
   228                                        // processed.
   336   bool               _verify;  // verify graph
   229 
   337 
   230   bool                    _collecting; // Indicates whether escape information
   338   JavaObjectNode* phantom_obj; // Unknown object
   231                                        // is still being collected. If false,
   339   JavaObjectNode*    null_obj;
   232                                        // no new nodes will be processed.
   340   Node*             _pcmp_neq; // ConI(#CC_GT)
   233 
   341   Node*              _pcmp_eq; // ConI(#CC_EQ)
   234   bool                    _progress;   // Indicates whether new Graph's edges
   342 
   235                                        // were created.
   343   Compile*           _compile; // Compile object for current compilation
   236 
   344   PhaseIterGVN*         _igvn; // Value numbering
   237   uint                _phantom_object; // Index of globally escaping object
   345 
   238                                        // that pointer values loaded from
   346   Unique_Node_List ideal_nodes; // Used by CG construction and types splitting.
   239                                        // a field which has not been set
       
   240                                        // are assumed to point to.
       
   241   uint                      _oop_null; // ConP(#NULL)->_idx
       
   242   uint                     _noop_null; // ConN(#NULL)->_idx
       
   243   Node*                     _pcmp_neq; // ConI(#CC_GT)
       
   244   Node*                      _pcmp_eq; // ConI(#CC_EQ)
       
   245 
       
   246   Compile *                  _compile; // Compile object for current compilation
       
   247   PhaseIterGVN *                _igvn; // Value numbering
       
   248 
   347 
   249   // Address of an element in _nodes.  Used when the element is to be modified
   348   // Address of an element in _nodes.  Used when the element is to be modified
   250   PointsToNode *ptnode_adr(uint idx) const {
   349   PointsToNode* ptnode_adr(int idx) const {
   251     // There should be no new ideal nodes during ConnectionGraph build,
   350     // There should be no new ideal nodes during ConnectionGraph build,
   252     // growableArray::adr_at() will throw assert otherwise.
   351     // growableArray::at() will throw assert otherwise.
   253     return _nodes.adr_at(idx);
   352     return _nodes.at(idx);
   254   }
   353   }
   255   uint nodes_size() const { return _nodes.length(); }
   354   uint nodes_size() const { return _nodes.length(); }
   256 
   355 
   257   bool is_null_ptr(uint idx) const { return (idx == _noop_null || idx == _oop_null); }
   356   // Add nodes to ConnectionGraph.
   258 
   357   void add_local_var(Node* n, PointsToNode::EscapeState es);
   259   // Add node to ConnectionGraph.
   358   void add_java_object(Node* n, PointsToNode::EscapeState es);
   260   void add_node(Node *n, PointsToNode::NodeType nt, PointsToNode::EscapeState es, bool done);
   359   void add_field(Node* n, PointsToNode::EscapeState es, int offset);
       
   360   void add_arraycopy(Node* n, PointsToNode::EscapeState es, PointsToNode* src, PointsToNode* dst);
       
   361 
       
   362   // Compute the escape state for arguments to a call.
       
   363   void process_call_arguments(CallNode *call);
       
   364 
       
   365   // Add PointsToNode node corresponding to a call
       
   366   void add_call_node(CallNode* call);
       
   367 
       
   368   // Map ideal node to existing PointsTo node (usually phantom_object).
       
   369   void map_ideal_node(Node *n, PointsToNode* ptn) {
       
   370     assert(ptn != NULL, "only existing PointsTo node");
       
   371     _nodes.at_put(n->_idx, ptn);
       
   372   }
       
   373 
       
   374   // Create PointsToNode node and add it to Connection Graph.
       
   375   void add_node_to_connection_graph(Node *n, Unique_Node_List *delayed_worklist);
       
   376 
       
   377   // Add final simple edges to graph.
       
   378   void add_final_edges(Node *n);
       
   379 
       
   380   // Finish Graph construction.
       
   381   bool complete_connection_graph(GrowableArray<PointsToNode*>&   ptnodes_worklist,
       
   382                                  GrowableArray<JavaObjectNode*>& non_escaped_worklist,
       
   383                                  GrowableArray<JavaObjectNode*>& java_objects_worklist,
       
   384                                  GrowableArray<FieldNode*>&      oop_fields_worklist);
       
   385 
       
   386 #ifdef ASSERT
       
   387   void verify_connection_graph(GrowableArray<PointsToNode*>&   ptnodes_worklist,
       
   388                                GrowableArray<JavaObjectNode*>& non_escaped_worklist,
       
   389                                GrowableArray<JavaObjectNode*>& java_objects_worklist,
       
   390                                GrowableArray<Node*>& addp_worklist);
       
   391 #endif
       
   392 
       
   393   // Add all references to this JavaObject node.
       
   394   int add_java_object_edges(JavaObjectNode* jobj, bool populate_worklist);
       
   395 
       
   396   // Put node on worklist if it is (or was) not there.
       
   397   void add_to_worklist(PointsToNode* pt) {
       
   398     _worklist.push(pt);
       
   399     return;
       
   400   }
       
   401 
       
   402   // Put on worklist all uses of this node.
       
   403   void add_uses_to_worklist(PointsToNode* pt) {
       
   404     for (UseIterator i(pt); i.has_next(); i.next())
       
   405       _worklist.push(i.get());
       
   406   }
       
   407 
       
   408   // Put on worklist all field's uses and related field nodes.
       
   409   void add_field_uses_to_worklist(FieldNode* field);
       
   410 
       
   411   // Put on worklist all related field nodes.
       
   412   void add_fields_to_worklist(FieldNode* field, PointsToNode* base);
       
   413 
       
   414   // Find fields which have unknown value.
       
   415   int find_field_value(FieldNode* field);
       
   416 
       
   417   // Find fields initializing values for allocations.
       
   418   int find_init_values(JavaObjectNode* ptn, PointsToNode* init_val, PhaseTransform* phase);
       
   419 
       
   420   // Set the escape state of an object and its fields.
       
   421   void set_escape_state(PointsToNode* ptn, PointsToNode::EscapeState esc) {
       
   422     // Don't change non-escaping state of NULL pointer.
       
   423     if (ptn != null_obj) {
       
   424       if (ptn->escape_state() < esc)
       
   425         ptn->set_escape_state(esc);
       
   426       if (ptn->fields_escape_state() < esc)
       
   427         ptn->set_fields_escape_state(esc);
       
   428     }
       
   429   }
       
   430   void set_fields_escape_state(PointsToNode* ptn, PointsToNode::EscapeState esc) {
       
   431     // Don't change non-escaping state of NULL pointer.
       
   432     if (ptn != null_obj) {
       
   433       if (ptn->fields_escape_state() < esc)
       
   434         ptn->set_fields_escape_state(esc);
       
   435     }
       
   436   }
       
   437 
       
   438   // Propagate GlobalEscape and ArgEscape escape states to all nodes
       
   439   // and check that we still have non-escaping java objects.
       
   440   bool find_non_escaped_objects(GrowableArray<PointsToNode*>& ptnodes_worklist,
       
   441                                 GrowableArray<JavaObjectNode*>& non_escaped_worklist);
       
   442 
       
   443   // Adjust scalar_replaceable state after Connection Graph is built.
       
   444   void adjust_scalar_replaceable_state(JavaObjectNode* jobj);
       
   445 
       
   446   // Optimize ideal graph.
       
   447   void optimize_ideal_graph(GrowableArray<Node*>& ptr_cmp_worklist,
       
   448                             GrowableArray<Node*>& storestore_worklist);
       
   449   // Optimize objects compare.
       
   450   Node* optimize_ptr_compare(Node* n);
       
   451 
       
   452   // Returns unique corresponding java object or NULL.
       
   453   JavaObjectNode* unique_java_object(Node *n);
       
   454 
       
   455   // Add an edge of the specified type pointing to the specified target.
       
   456   bool add_edge(PointsToNode* from, PointsToNode* to) {
       
   457     assert(!from->is_Field() || from->as_Field()->is_oop(), "sanity");
       
   458 
       
   459     if (to == phantom_obj) {
       
   460       if (from->has_unknown_ptr()) {
       
   461         return false; // already points to phantom_obj
       
   462       }
       
   463       from->set_has_unknown_ptr();
       
   464     }
       
   465 
       
   466     bool is_new = from->add_edge(to);
       
   467     assert(to != phantom_obj || is_new, "sanity");
       
   468     if (is_new) { // New edge?
       
   469       assert(!_verify, "graph is incomplete");
       
   470       is_new = to->add_use(from);
       
   471       assert(is_new, "use should be also new");
       
   472     }
       
   473     return is_new;
       
   474   }
       
   475 
       
   476   // Add an edge from Field node to its base and back.
       
   477   bool add_base(FieldNode* from, PointsToNode* to) {
       
   478     assert(!to->is_Arraycopy(), "sanity");
       
   479     if (to == phantom_obj) {
       
   480       if (from->has_unknown_base()) {
       
   481         return false; // already has phantom_obj base
       
   482       }
       
   483       from->set_has_unknown_base();
       
   484     }
       
   485     bool is_new = from->add_base(to);
       
   486     assert(to != phantom_obj || is_new, "sanity");
       
   487     if (is_new) {      // New edge?
       
   488       assert(!_verify, "graph is incomplete");
       
   489       if (to == null_obj)
       
   490         return is_new; // Don't add fields to NULL pointer.
       
   491       if (to->is_JavaObject()) {
       
   492         is_new = to->add_edge(from);
       
   493       } else {
       
   494         is_new = to->add_base_use(from);
       
   495       }
       
   496       assert(is_new, "use should be also new");
       
   497     }
       
   498     return is_new;
       
   499   }
       
   500 
       
   501   // Add LocalVar node and edge if possible
       
   502   void add_local_var_and_edge(Node* n, PointsToNode::EscapeState es, Node* to,
       
   503                               Unique_Node_List *delayed_worklist) {
       
   504     PointsToNode* ptn = ptnode_adr(to->_idx);
       
   505     if (delayed_worklist != NULL) { // First iteration of CG construction
       
   506       add_local_var(n, es);
       
   507       if (ptn == NULL) {
       
   508         delayed_worklist->push(n);
       
   509         return; // Process it later.
       
   510       }
       
   511     } else {
       
   512       assert(ptn != NULL, "node should be registered");
       
   513     }
       
   514     add_edge(ptnode_adr(n->_idx), ptn);
       
   515   }
       
   516 
       
   517   // Helper functions
       
   518   bool   is_oop_field(Node* n, int offset);
       
   519   static Node* get_addp_base(Node *addp);
       
   520   static Node* find_second_addp(Node* addp, Node* n);
   261 
   521 
   262   // offset of a field reference
   522   // offset of a field reference
   263   int address_offset(Node* adr, PhaseTransform *phase);
   523   int address_offset(Node* adr, PhaseTransform *phase);
   264 
   524 
   265   // compute the escape state for arguments to a call
   525 
   266   void process_call_arguments(CallNode *call, PhaseTransform *phase);
   526   // Propagate unique types created for unescaped allocated objects
   267 
   527   // through the graph
   268   // compute the escape state for the return value of a call
   528   void split_unique_types(GrowableArray<Node *>  &alloc_worklist);
   269   void process_call_result(ProjNode *resproj, PhaseTransform *phase);
   529 
   270 
   530   // Helper methods for unique types split.
   271   // Populate Connection Graph with Ideal nodes.
   531   bool split_AddP(Node *addp, Node *base);
   272   void record_for_escape_analysis(Node *n, PhaseTransform *phase);
   532 
   273 
   533   PhiNode *create_split_phi(PhiNode *orig_phi, int alias_idx, GrowableArray<PhiNode *>  &orig_phi_worklist, bool &new_created);
   274   // Build Connection Graph and set nodes escape state.
   534   PhiNode *split_memory_phi(PhiNode *orig_phi, int alias_idx, GrowableArray<PhiNode *>  &orig_phi_worklist);
   275   void build_connection_graph(Node *n, PhaseTransform *phase);
   535 
   276 
   536   void  move_inst_mem(Node* n, GrowableArray<PhiNode *>  &orig_phis);
   277   // walk the connection graph starting at the node corresponding to "n" and
   537   Node* find_inst_mem(Node* mem, int alias_idx,GrowableArray<PhiNode *>  &orig_phi_worklist);
   278   // add the index of everything it could point to, to "ptset".  This may cause
   538   Node* step_through_mergemem(MergeMemNode *mmem, int alias_idx, const TypeOopPtr *toop);
   279   // Phi's encountered to get (re)processed  (which requires "phase".)
   539 
   280   VectorSet* PointsTo(Node * n);
   540 
   281 
   541   GrowableArray<MergeMemNode*>  _mergemem_worklist; // List of all MergeMem nodes
   282   // Reused structures for PointsTo().
       
   283   VectorSet            pt_ptset;
       
   284   VectorSet            pt_visited;
       
   285   GrowableArray<uint>  pt_worklist;
       
   286 
       
   287   //  Edge manipulation.  The "from_i" and "to_i" arguments are the
       
   288   //  node indices of the source and destination of the edge
       
   289   void add_pointsto_edge(uint from_i, uint to_i);
       
   290   void add_deferred_edge(uint from_i, uint to_i);
       
   291   void add_field_edge(uint from_i, uint to_i, int offs);
       
   292 
       
   293   // Add an edge of the specified type pointing to the specified target.
       
   294   // Set _progress if new edge is added.
       
   295   void add_edge(PointsToNode *f, uint to_i, PointsToNode::EdgeType et) {
       
   296     uint e_cnt = f->edge_count();
       
   297     f->add_edge(to_i, et);
       
   298     _progress |= (f->edge_count() != e_cnt);
       
   299   }
       
   300 
       
   301   // Add an edge to node given by "to_i" from any field of adr_i whose offset
       
   302   // matches "offset"  A deferred edge is added if to_i is a LocalVar, and
       
   303   // a pointsto edge is added if it is a JavaObject
       
   304   void add_edge_from_fields(uint adr, uint to_i, int offs);
       
   305 
       
   306   // Add a deferred  edge from node given by "from_i" to any field
       
   307   // of adr_i whose offset matches "offset"
       
   308   void add_deferred_edge_to_fields(uint from_i, uint adr, int offs);
       
   309 
       
   310 
       
   311   // Remove outgoing deferred edges from the node referenced by "ni".
       
   312   // Any outgoing edges from the target of the deferred edge are copied
       
   313   // to "ni".
       
   314   void remove_deferred(uint ni, GrowableArray<uint>* deferred_edges, VectorSet* visited);
       
   315 
   542 
   316   Node_Array _node_map; // used for bookeeping during type splitting
   543   Node_Array _node_map; // used for bookeeping during type splitting
   317                         // Used for the following purposes:
   544                         // Used for the following purposes:
   318                         // Memory Phi    - most recent unique Phi split out
   545                         // Memory Phi    - most recent unique Phi split out
   319                         //                 from this Phi
   546                         //                 from this Phi
   320                         // MemNode       - new memory input for this node
   547                         // MemNode       - new memory input for this node
   321                         // ChecCastPP    - allocation that this is a cast of
   548                         // ChecCastPP    - allocation that this is a cast of
   322                         // allocation    - CheckCastPP of the allocation
   549                         // allocation    - CheckCastPP of the allocation
   323   bool split_AddP(Node *addp, Node *base,  PhaseGVN  *igvn);
       
   324   PhiNode *create_split_phi(PhiNode *orig_phi, int alias_idx, GrowableArray<PhiNode *>  &orig_phi_worklist, PhaseGVN  *igvn, bool &new_created);
       
   325   PhiNode *split_memory_phi(PhiNode *orig_phi, int alias_idx, GrowableArray<PhiNode *>  &orig_phi_worklist, PhaseGVN  *igvn);
       
   326   void  move_inst_mem(Node* n, GrowableArray<PhiNode *>  &orig_phis, PhaseGVN *igvn);
       
   327   Node *find_inst_mem(Node *mem, int alias_idx,GrowableArray<PhiNode *>  &orig_phi_worklist,  PhaseGVN  *igvn);
       
   328 
       
   329   // Propagate unique types created for unescaped allocated objects
       
   330   // through the graph
       
   331   void split_unique_types(GrowableArray<Node *>  &alloc_worklist);
       
   332 
   550 
   333   // manage entries in _node_map
   551   // manage entries in _node_map
   334   void  set_map(int idx, Node *n)        { _node_map.map(idx, n); }
   552 
   335   Node *get_map(int idx)                 { return _node_map[idx]; }
   553   void  set_map(Node* from, Node* to)  {
   336   PhiNode *get_map_phi(int idx) {
   554     ideal_nodes.push(from);
   337     Node *phi = _node_map[idx];
   555     _node_map.map(from->_idx, to);
       
   556   }
       
   557 
       
   558   Node* get_map(int idx) { return _node_map[idx]; }
       
   559 
       
   560   PhiNode* get_map_phi(int idx) {
       
   561     Node* phi = _node_map[idx];
   338     return (phi == NULL) ? NULL : phi->as_Phi();
   562     return (phi == NULL) ? NULL : phi->as_Phi();
   339   }
   563   }
   340 
   564 
   341   // Notify optimizer that a node has been modified
   565   // Notify optimizer that a node has been modified
   342   void record_for_optimizer(Node *n) {
   566   void record_for_optimizer(Node *n) {
   343     _igvn->_worklist.push(n);
   567     _igvn->_worklist.push(n);
   344     _igvn->add_users_to_worklist(n);
   568     _igvn->add_users_to_worklist(n);
   345   }
   569   }
   346 
   570 
   347   // Set the escape state of a node
       
   348   void set_escape_state(uint ni, PointsToNode::EscapeState es);
       
   349 
       
   350   // Find fields initializing values for allocations.
       
   351   void find_init_values(Node* n, VectorSet* visited, PhaseTransform* phase);
       
   352 
       
   353   // Adjust escape state after Connection Graph is built.
       
   354   void adjust_escape_state(Node* n);
       
   355 
       
   356   // Propagate escape states to referenced nodes.
       
   357   bool propagate_escape_state(GrowableArray<int>* cg_worklist,
       
   358                               GrowableArray<uint>* worklist,
       
   359                               PointsToNode::EscapeState esc_state);
       
   360 
       
   361   // Optimize objects compare.
       
   362   Node* optimize_ptr_compare(Node* n);
       
   363 
       
   364   // Compute the escape information
   571   // Compute the escape information
   365   bool compute_escape();
   572   bool compute_escape();
   366 
   573 
   367 public:
   574 public:
   368   ConnectionGraph(Compile *C, PhaseIterGVN *igvn);
   575   ConnectionGraph(Compile *C, PhaseIterGVN *igvn);
   371   static bool has_candidates(Compile *C);
   578   static bool has_candidates(Compile *C);
   372 
   579 
   373   // Perform escape analysis
   580   // Perform escape analysis
   374   static void do_analysis(Compile *C, PhaseIterGVN *igvn);
   581   static void do_analysis(Compile *C, PhaseIterGVN *igvn);
   375 
   582 
   376   // escape state of a node
   583   bool not_global_escape(Node *n);
   377   PointsToNode::EscapeState escape_state(Node *n);
       
   378 
   584 
   379 #ifndef PRODUCT
   585 #ifndef PRODUCT
   380   void dump();
   586   void dump(GrowableArray<PointsToNode*>& ptnodes_worklist);
   381 #endif
   587 #endif
   382 };
   588 };
   383 
   589 
   384 #endif // SHARE_VM_OPTO_ESCAPE_HPP
   590 #endif // SHARE_VM_OPTO_ESCAPE_HPP