1 /* 2 * Copyright (c) 2005, 2019, Oracle and/or its affiliates. All rights reserved. 3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. 4 * 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 7 * published by the Free Software Foundation. 8 * 9 * This code is distributed in the hope that it will be useful, but WITHOUT 10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 12 * version 2 for more details (a copy is included in the LICENSE file that 13 * accompanied this code). 14 * 15 * You should have received a copy of the GNU General Public License version 16 * 2 along with this work; if not, write to the Free Software Foundation, 17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. 18 * 19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA 20 * or visit www.oracle.com if you need additional information or have any 21 * questions. 22 * 23 */ 24 25 #ifndef SHARE_OPTO_ESCAPE_HPP 26 #define SHARE_OPTO_ESCAPE_HPP 27 28 #include "opto/addnode.hpp" 29 #include "opto/node.hpp" 30 #include "utilities/growableArray.hpp" 31 32 // 33 // Adaptation for C2 of the escape analysis algorithm described in: 34 // 35 // [Choi99] Jong-Deok Shoi, Manish Gupta, Mauricio Seffano, 36 // Vugranam C. Sreedhar, Sam Midkiff, 37 // "Escape Analysis for Java", Procedings of ACM SIGPLAN 38 // OOPSLA Conference, November 1, 1999 39 // 40 // The flow-insensitive analysis described in the paper has been implemented. 41 // 42 // The analysis requires construction of a "connection graph" (CG) for 43 // the method being analyzed. The nodes of the connection graph are: 44 // 45 // - Java objects (JO) 46 // - Local variables (LV) 47 // - Fields of an object (OF), these also include array elements 48 // 49 // The CG contains 3 types of edges: 50 // 51 // - PointsTo (-P>) {LV, OF} to JO 52 // - Deferred (-D>) from {LV, OF} to {LV, OF} 53 // - Field (-F>) from JO to OF 54 // 55 // The following utility functions is used by the algorithm: 56 // 57 // PointsTo(n) - n is any CG node, it returns the set of JO that n could 58 // point to. 59 // 60 // The algorithm describes how to construct the connection graph 61 // in the following 4 cases: 62 // 63 // Case Edges Created 64 // 65 // (1) p = new T() LV -P> JO 66 // (2) p = q LV -D> LV 67 // (3) p.f = q JO -F> OF, OF -D> LV 68 // (4) p = q.f JO -F> OF, LV -D> OF 69 // 70 // In all these cases, p and q are local variables. For static field 71 // references, we can construct a local variable containing a reference 72 // to the static memory. 73 // 74 // C2 does not have local variables. However for the purposes of constructing 75 // the connection graph, the following IR nodes are treated as local variables: 76 // Phi (pointer values) 77 // LoadP, LoadN 78 // Proj#5 (value returned from callnodes including allocations) 79 // CheckCastPP, CastPP 80 // 81 // The LoadP, Proj and CheckCastPP behave like variables assigned to only once. 82 // Only a Phi can have multiple assignments. Each input to a Phi is treated 83 // as an assignment to it. 84 // 85 // The following node types are JavaObject: 86 // 87 // phantom_object (general globally escaped object) 88 // Allocate 89 // AllocateArray 90 // Parm (for incoming arguments) 91 // CastX2P ("unsafe" operations) 92 // CreateEx 93 // ConP 94 // LoadKlass 95 // ThreadLocal 96 // CallStaticJava (which returns Object) 97 // 98 // AddP nodes are fields. 99 // 100 // After building the graph, a pass is made over the nodes, deleting deferred 101 // nodes and copying the edges from the target of the deferred edge to the 102 // source. This results in a graph with no deferred edges, only: 103 // 104 // LV -P> JO 105 // OF -P> JO (the object whose oop is stored in the field) 106 // JO -F> OF 107 // 108 // Then, for each node which is GlobalEscape, anything it could point to 109 // is marked GlobalEscape. Finally, for any node marked ArgEscape, anything 110 // it could point to is marked ArgEscape. 111 // 112 113 class Compile; 114 class Node; 115 class CallNode; 116 class PhiNode; 117 class PhaseTransform; 118 class PointsToNode; 119 class Type; 120 class TypePtr; 121 class VectorSet; 122 123 class JavaObjectNode; 124 class LocalVarNode; 125 class FieldNode; 126 class ArraycopyNode; 127 128 class ConnectionGraph; 129 130 // ConnectionGraph nodes 131 class PointsToNode : public ResourceObj { 132 GrowableArray<PointsToNode*> _edges; // List of nodes this node points to 133 GrowableArray<PointsToNode*> _uses; // List of nodes which point to this node 134 135 const u1 _type; // NodeType 136 u1 _flags; // NodeFlags 137 u1 _escape; // EscapeState of object 138 u1 _fields_escape; // EscapeState of object's fields 139 140 Node* const _node; // Ideal node corresponding to this PointsTo node. 141 const int _idx; // Cached ideal node's _idx 142 const uint _pidx; // Index of this node 143 144 public: 145 typedef enum { 146 UnknownType = 0, 147 JavaObject = 1, 148 LocalVar = 2, 149 Field = 3, 150 Arraycopy = 4 151 } NodeType; 152 153 typedef enum { 154 UnknownEscape = 0, 155 NoEscape = 1, // An object does not escape method or thread and it is 156 // not passed to call. It could be replaced with scalar. 157 ArgEscape = 2, // An object does not escape method or thread but it is 158 // passed as argument to call or referenced by argument 159 // and it does not escape during call. 160 GlobalEscape = 3 // An object escapes the method or thread. 161 } EscapeState; 162 163 typedef enum { 164 ScalarReplaceable = 1, // Not escaped object could be replaced with scalar 165 PointsToUnknown = 2, // Has edge to phantom_object 166 ArraycopySrc = 4, // Has edge from Arraycopy node 167 ArraycopyDst = 8 // Has edge to Arraycopy node 168 } NodeFlags; 169 170 171 inline PointsToNode(ConnectionGraph* CG, Node* n, EscapeState es, NodeType type); 172 173 uint pidx() const { return _pidx; } 174 175 Node* ideal_node() const { return _node; } 176 int idx() const { return _idx; } 177 178 bool is_JavaObject() const { return _type == (u1)JavaObject; } 179 bool is_LocalVar() const { return _type == (u1)LocalVar; } 180 bool is_Field() const { return _type == (u1)Field; } 181 bool is_Arraycopy() const { return _type == (u1)Arraycopy; } 182 183 JavaObjectNode* as_JavaObject() { assert(is_JavaObject(),""); return (JavaObjectNode*)this; } 184 LocalVarNode* as_LocalVar() { assert(is_LocalVar(),""); return (LocalVarNode*)this; } 185 FieldNode* as_Field() { assert(is_Field(),""); return (FieldNode*)this; } 186 ArraycopyNode* as_Arraycopy() { assert(is_Arraycopy(),""); return (ArraycopyNode*)this; } 187 188 EscapeState escape_state() const { return (EscapeState)_escape; } 189 void set_escape_state(EscapeState state) { _escape = (u1)state; } 190 191 EscapeState fields_escape_state() const { return (EscapeState)_fields_escape; } 192 void set_fields_escape_state(EscapeState state) { _fields_escape = (u1)state; } 193 194 bool has_unknown_ptr() const { return (_flags & PointsToUnknown) != 0; } 195 void set_has_unknown_ptr() { _flags |= PointsToUnknown; } 196 197 bool arraycopy_src() const { return (_flags & ArraycopySrc) != 0; } 198 void set_arraycopy_src() { _flags |= ArraycopySrc; } 199 bool arraycopy_dst() const { return (_flags & ArraycopyDst) != 0; } 200 void set_arraycopy_dst() { _flags |= ArraycopyDst; } 201 202 bool scalar_replaceable() const { return (_flags & ScalarReplaceable) != 0;} 203 void set_scalar_replaceable(bool v) { 204 if (v) 205 _flags |= ScalarReplaceable; 206 else 207 _flags &= ~ScalarReplaceable; 208 } 209 210 int edge_count() const { return _edges.length(); } 211 PointsToNode* edge(int e) const { return _edges.at(e); } 212 bool add_edge(PointsToNode* edge) { return _edges.append_if_missing(edge); } 213 214 int use_count() const { return _uses.length(); } 215 PointsToNode* use(int e) const { return _uses.at(e); } 216 bool add_use(PointsToNode* use) { return _uses.append_if_missing(use); } 217 218 // Mark base edge use to distinguish from stored value edge. 219 bool add_base_use(FieldNode* use) { return _uses.append_if_missing((PointsToNode*)((intptr_t)use + 1)); } 220 static bool is_base_use(PointsToNode* use) { return (((intptr_t)use) & 1); } 221 static PointsToNode* get_use_node(PointsToNode* use) { return (PointsToNode*)(((intptr_t)use) & ~1); } 222 223 // Return true if this node points to specified node or nodes it points to. 224 bool points_to(JavaObjectNode* ptn) const; 225 226 // Return true if this node points only to non-escaping allocations. 227 bool non_escaping_allocation(); 228 229 // Return true if one node points to an other. 230 bool meet(PointsToNode* ptn); 231 232 #ifndef PRODUCT 233 NodeType node_type() const { return (NodeType)_type;} 234 void dump(bool print_state=true) const; 235 #endif 236 237 }; 238 239 class LocalVarNode: public PointsToNode { 240 public: 241 LocalVarNode(ConnectionGraph *CG, Node* n, EscapeState es): 242 PointsToNode(CG, n, es, LocalVar) {} 243 }; 244 245 class JavaObjectNode: public PointsToNode { 246 public: 247 JavaObjectNode(ConnectionGraph *CG, Node* n, EscapeState es): 248 PointsToNode(CG, n, es, JavaObject) { 249 if (es > NoEscape) 250 set_scalar_replaceable(false); 251 } 252 }; 253 254 class FieldNode: public PointsToNode { 255 GrowableArray<PointsToNode*> _bases; // List of JavaObject nodes which point to this node 256 const int _offset; // Field's offset. 257 const bool _is_oop; // Field points to object 258 bool _has_unknown_base; // Has phantom_object base 259 public: 260 FieldNode(ConnectionGraph *CG, Node* n, EscapeState es, int offs, bool is_oop): 261 PointsToNode(CG, n, es, Field), 262 _offset(offs), _is_oop(is_oop), 263 _has_unknown_base(false) {} 264 265 int offset() const { return _offset;} 266 bool is_oop() const { return _is_oop;} 267 bool has_unknown_base() const { return _has_unknown_base; } 268 void set_has_unknown_base() { _has_unknown_base = true; } 269 270 int base_count() const { return _bases.length(); } 271 PointsToNode* base(int e) const { return _bases.at(e); } 272 bool add_base(PointsToNode* base) { return _bases.append_if_missing(base); } 273 #ifdef ASSERT 274 // Return true if bases points to this java object. 275 bool has_base(JavaObjectNode* ptn) const; 276 #endif 277 278 }; 279 280 class ArraycopyNode: public PointsToNode { 281 public: 282 ArraycopyNode(ConnectionGraph *CG, Node* n, EscapeState es): 283 PointsToNode(CG, n, es, Arraycopy) {} 284 }; 285 286 // Iterators for PointsTo node's edges: 287 // for (EdgeIterator i(n); i.has_next(); i.next()) { 288 // PointsToNode* u = i.get(); 289 class PointsToIterator: public StackObj { 290 protected: 291 const PointsToNode* node; 292 const int cnt; 293 int i; 294 public: 295 inline PointsToIterator(const PointsToNode* n, int cnt) : node(n), cnt(cnt), i(0) { } 296 inline bool has_next() const { return i < cnt; } 297 inline void next() { i++; } 298 PointsToNode* get() const { ShouldNotCallThis(); return NULL; } 299 }; 300 301 class EdgeIterator: public PointsToIterator { 302 public: 303 inline EdgeIterator(const PointsToNode* n) : PointsToIterator(n, n->edge_count()) { } 304 inline PointsToNode* get() const { return node->edge(i); } 305 }; 306 307 class UseIterator: public PointsToIterator { 308 public: 309 inline UseIterator(const PointsToNode* n) : PointsToIterator(n, n->use_count()) { } 310 inline PointsToNode* get() const { return node->use(i); } 311 }; 312 313 class BaseIterator: public PointsToIterator { 314 public: 315 inline BaseIterator(const FieldNode* n) : PointsToIterator(n, n->base_count()) { } 316 inline PointsToNode* get() const { return ((PointsToNode*)node)->as_Field()->base(i); } 317 }; 318 319 320 class ConnectionGraph: public ResourceObj { 321 friend class PointsToNode; 322 private: 323 GrowableArray<PointsToNode*> _nodes; // Map from ideal nodes to 324 // ConnectionGraph nodes. 325 326 GrowableArray<PointsToNode*> _worklist; // Nodes to be processed 327 VectorSet _in_worklist; 328 uint _next_pidx; 329 330 bool _collecting; // Indicates whether escape information 331 // is still being collected. If false, 332 // no new nodes will be processed. 333 334 bool _verify; // verify graph 335 336 bool _has_locks; // Used by stack allocation 337 338 JavaObjectNode* null_obj; 339 Node* _pcmp_neq; // ConI(#CC_GT) 340 Node* _pcmp_eq; // ConI(#CC_EQ) 341 342 Compile* _compile; // Compile object for current compilation 343 PhaseIterGVN* _igvn; // Value numbering 344 345 Unique_Node_List ideal_nodes; // Used by CG construction and types splitting. 346 347 public: 348 JavaObjectNode* phantom_obj; // Unknown object 349 350 private: 351 // Address of an element in _nodes. Used when the element is to be modified 352 PointsToNode* ptnode_adr(int idx) const { 353 // There should be no new ideal nodes during ConnectionGraph build, 354 // growableArray::at() will throw assert otherwise. 355 return _nodes.at(idx); 356 } 357 uint nodes_size() const { return _nodes.length(); } 358 359 uint next_pidx() { return _next_pidx++; } 360 361 // Add nodes to ConnectionGraph. 362 void add_local_var(Node* n, PointsToNode::EscapeState es); 363 void add_java_object(Node* n, PointsToNode::EscapeState es); 364 void add_field(Node* n, PointsToNode::EscapeState es, int offset); 365 void add_arraycopy(Node* n, PointsToNode::EscapeState es, PointsToNode* src, PointsToNode* dst); 366 367 // Compute the escape state for arguments to a call. 368 void process_call_arguments(CallNode *call); 369 370 // Add PointsToNode node corresponding to a call 371 void add_call_node(CallNode* call); 372 373 // Create PointsToNode node and add it to Connection Graph. 374 void add_node_to_connection_graph(Node *n, Unique_Node_List *delayed_worklist); 375 376 // Add final simple edges to graph. 377 void add_final_edges(Node *n); 378 379 // Finish Graph construction. 380 bool complete_connection_graph(GrowableArray<PointsToNode*>& ptnodes_worklist, 381 GrowableArray<JavaObjectNode*>& non_escaped_worklist, 382 GrowableArray<JavaObjectNode*>& java_objects_worklist, 383 GrowableArray<FieldNode*>& oop_fields_worklist); 384 385 #ifdef ASSERT 386 void verify_connection_graph(GrowableArray<PointsToNode*>& ptnodes_worklist, 387 GrowableArray<JavaObjectNode*>& non_escaped_worklist, 388 GrowableArray<JavaObjectNode*>& java_objects_worklist, 389 GrowableArray<Node*>& addp_worklist); 390 #endif 391 392 // Add all references to this JavaObject node. 393 int add_java_object_edges(JavaObjectNode* jobj, bool populate_worklist); 394 395 // Put node on worklist if it is (or was) not there. 396 inline void add_to_worklist(PointsToNode* pt) { 397 PointsToNode* ptf = pt; 398 uint pidx_bias = 0; 399 if (PointsToNode::is_base_use(pt)) { 400 // Create a separate entry in _in_worklist for a marked base edge 401 // because _worklist may have an entry for a normal edge pointing 402 // to the same node. To separate them use _next_pidx as bias. 403 ptf = PointsToNode::get_use_node(pt)->as_Field(); 404 pidx_bias = _next_pidx; 405 } 406 if (!_in_worklist.test_set(ptf->pidx() + pidx_bias)) { 407 _worklist.append(pt); 408 } 409 } 410 411 // Put on worklist all uses of this node. 412 inline void add_uses_to_worklist(PointsToNode* pt) { 413 for (UseIterator i(pt); i.has_next(); i.next()) { 414 add_to_worklist(i.get()); 415 } 416 } 417 418 // Put on worklist all field's uses and related field nodes. 419 void add_field_uses_to_worklist(FieldNode* field); 420 421 // Put on worklist all related field nodes. 422 void add_fields_to_worklist(FieldNode* field, PointsToNode* base); 423 424 // Find fields which have unknown value. 425 int find_field_value(FieldNode* field); 426 427 // Find fields initializing values for allocations. 428 int find_init_values(JavaObjectNode* ptn, PointsToNode* init_val, PhaseTransform* phase); 429 430 // Set the escape state of an object and its fields. 431 void set_escape_state(PointsToNode* ptn, PointsToNode::EscapeState esc) { 432 // Don't change non-escaping state of NULL pointer. 433 if (ptn != null_obj) { 434 if (ptn->escape_state() < esc) 435 ptn->set_escape_state(esc); 436 if (ptn->fields_escape_state() < esc) 437 ptn->set_fields_escape_state(esc); 438 } 439 } 440 void set_fields_escape_state(PointsToNode* ptn, PointsToNode::EscapeState esc) { 441 // Don't change non-escaping state of NULL pointer. 442 if (ptn != null_obj) { 443 if (ptn->fields_escape_state() < esc) 444 ptn->set_fields_escape_state(esc); 445 } 446 } 447 448 // Propagate GlobalEscape and ArgEscape escape states to all nodes 449 // and check that we still have non-escaping java objects. 450 bool find_non_escaped_objects(GrowableArray<PointsToNode*>& ptnodes_worklist, 451 GrowableArray<JavaObjectNode*>& non_escaped_worklist); 452 453 // Adjust scalar_replaceable state after Connection Graph is built. 454 void adjust_scalar_replaceable_state(JavaObjectNode* jobj); 455 456 // Optimize ideal graph. 457 void optimize_ideal_graph(GrowableArray<Node*>& ptr_cmp_worklist, 458 GrowableArray<Node*>& storestore_worklist); 459 // Optimize objects compare. 460 Node* optimize_ptr_compare(Node* n); 461 462 // Returns unique corresponding java object or NULL. 463 JavaObjectNode* unique_java_object(Node *n); 464 465 // Add an edge of the specified type pointing to the specified target. 466 bool add_edge(PointsToNode* from, PointsToNode* to) { 467 assert(!from->is_Field() || from->as_Field()->is_oop(), "sanity"); 468 469 if (to == phantom_obj) { 470 if (from->has_unknown_ptr()) { 471 return false; // already points to phantom_obj 472 } 473 from->set_has_unknown_ptr(); 474 } 475 476 bool is_new = from->add_edge(to); 477 assert(to != phantom_obj || is_new, "sanity"); 478 if (is_new) { // New edge? 479 assert(!_verify, "graph is incomplete"); 480 is_new = to->add_use(from); 481 assert(is_new, "use should be also new"); 482 } 483 return is_new; 484 } 485 486 // Add an edge from Field node to its base and back. 487 bool add_base(FieldNode* from, PointsToNode* to) { 488 assert(!to->is_Arraycopy(), "sanity"); 489 if (to == phantom_obj) { 490 if (from->has_unknown_base()) { 491 return false; // already has phantom_obj base 492 } 493 from->set_has_unknown_base(); 494 } 495 bool is_new = from->add_base(to); 496 assert(to != phantom_obj || is_new, "sanity"); 497 if (is_new) { // New edge? 498 assert(!_verify, "graph is incomplete"); 499 if (to == null_obj) 500 return is_new; // Don't add fields to NULL pointer. 501 if (to->is_JavaObject()) { 502 is_new = to->add_edge(from); 503 } else { 504 is_new = to->add_base_use(from); 505 } 506 assert(is_new, "use should be also new"); 507 } 508 return is_new; 509 } 510 511 // Helper functions 512 bool is_oop_field(Node* n, int offset, bool* unsafe); 513 static Node* find_second_addp(Node* addp, Node* n); 514 // offset of a field reference 515 int address_offset(Node* adr, PhaseTransform *phase); 516 517 518 // Propagate unique types created for unescaped allocated objects 519 // through the graph 520 void split_unique_types(GrowableArray<Node *> &alloc_worklist, GrowableArray<ArrayCopyNode*> &arraycopy_worklist); 521 522 // Helper methods for unique types split. 523 bool split_AddP(Node *addp, Node *base); 524 525 PhiNode *create_split_phi(PhiNode *orig_phi, int alias_idx, GrowableArray<PhiNode *> &orig_phi_worklist, bool &new_created); 526 PhiNode *split_memory_phi(PhiNode *orig_phi, int alias_idx, GrowableArray<PhiNode *> &orig_phi_worklist); 527 528 void move_inst_mem(Node* n, GrowableArray<PhiNode *> &orig_phis); 529 Node* find_inst_mem(Node* mem, int alias_idx,GrowableArray<PhiNode *> &orig_phi_worklist); 530 Node* step_through_mergemem(MergeMemNode *mmem, int alias_idx, const TypeOopPtr *toop); 531 532 533 GrowableArray<MergeMemNode*> _mergemem_worklist; // List of all MergeMem nodes 534 535 Node_Array _node_map; // used for bookeeping during type splitting 536 // Used for the following purposes: 537 // Memory Phi - most recent unique Phi split out 538 // from this Phi 539 // MemNode - new memory input for this node 540 // ChecCastPP - allocation that this is a cast of 541 // allocation - CheckCastPP of the allocation 542 543 // manage entries in _node_map 544 545 void set_map(Node* from, Node* to) { 546 ideal_nodes.push(from); 547 _node_map.map(from->_idx, to); 548 } 549 550 Node* get_map(int idx) { return _node_map[idx]; } 551 552 PhiNode* get_map_phi(int idx) { 553 Node* phi = _node_map[idx]; 554 return (phi == NULL) ? NULL : phi->as_Phi(); 555 } 556 557 // Notify optimizer that a node has been modified 558 void record_for_optimizer(Node *n); 559 560 // Compute the escape information 561 bool compute_escape(); 562 563 public: 564 ConnectionGraph(Compile *C, PhaseIterGVN *igvn); 565 566 // Check for non-escaping candidates 567 static bool has_candidates(Compile *C); 568 569 // Perform escape analysis 570 static void do_analysis(Compile *C, PhaseIterGVN *igvn); 571 572 bool not_global_escape(Node *n); 573 574 // To be used by, e.g., BarrierSetC2 impls 575 Node* get_addp_base(Node* addp); 576 577 // Utility function for nodes that load an object 578 void add_objload_to_connection_graph(Node* n, Unique_Node_List* delayed_worklist); 579 580 // Add LocalVar node and edge if possible 581 void add_local_var_and_edge(Node* n, PointsToNode::EscapeState es, Node* to, 582 Unique_Node_List *delayed_worklist) { 583 PointsToNode* ptn = ptnode_adr(to->_idx); 584 if (delayed_worklist != NULL) { // First iteration of CG construction 585 add_local_var(n, es); 586 if (ptn == NULL) { 587 delayed_worklist->push(n); 588 return; // Process it later. 589 } 590 } else { 591 assert(ptn != NULL, "node should be registered"); 592 } 593 add_edge(ptnode_adr(n->_idx), ptn); 594 } 595 596 // Map ideal node to existing PointsTo node (usually phantom_object). 597 void map_ideal_node(Node *n, PointsToNode* ptn) { 598 assert(ptn != NULL, "only existing PointsTo node"); 599 _nodes.at_put(n->_idx, ptn); 600 } 601 602 void add_to_congraph_unsafe_access(Node* n, uint opcode, Unique_Node_List* delayed_worklist); 603 bool add_final_edges_unsafe_access(Node* n, uint opcode); 604 605 // Helpers for stack allocation 606 607 // If an allocation is dominated by a loop, check to see if the lifetime of two instances 608 // may overlap. If they do this allocate is not eligible for stack allocation 609 bool allocation_lifetime_overlap(AllocateNode *alloc, PhiNode *phi); 610 // Stack allocation has limited support for compressed references at the moment. 611 // This helper checks if an oop may be compressed at some point in the graph. 612 bool oop_may_be_compressed(Node* alloc_result); 613 // Check if the alloc node is eligible for stack allocation 614 bool eligible_for_stack_allocation(PointsToNode* ptn); 615 // Check if the alloc has uses that make it ineligible for stack allocation 616 bool all_uses_eligible_for_stack_allocation(PointsToNode *ptn); 617 // Verify object chains for stack allocated objects. Heap objects cannot point to stack allocated objects. 618 bool verify_stack_allocated_object_chains(GrowableArray<JavaObjectNode*> &non_escaped_worklist, int non_escaped_length); 619 #ifndef PRODUCT 620 void print_stack_allocated_candidates(GrowableArray<JavaObjectNode*> &non_escaped_worklist, int non_escaped_length); 621 #endif 622 623 #ifndef PRODUCT 624 void dump(GrowableArray<PointsToNode*>& ptnodes_worklist); 625 626 bool print_escape_analysis() { 627 return PrintEscapeAnalysis || _compile->directive()->PrintEscapeAnalysisOption; 628 } 629 630 bool print_eliminate_allocations() { 631 return PrintEliminateAllocations || _compile->directive()->PrintEliminateAllocationsOption; 632 } 633 634 bool print_stack_allocation() { 635 return PrintStackAllocation || _compile->directive()->PrintStackAllocationOption; 636 } 637 #endif 638 }; 639 640 inline PointsToNode::PointsToNode(ConnectionGraph *CG, Node* n, EscapeState es, NodeType type): 641 _edges(CG->_compile->comp_arena(), 2, 0, NULL), 642 _uses (CG->_compile->comp_arena(), 2, 0, NULL), 643 _type((u1)type), 644 _flags(ScalarReplaceable), 645 _escape((u1)es), 646 _fields_escape((u1)es), 647 _node(n), 648 _idx(n->_idx), 649 _pidx(CG->next_pidx()) { 650 assert(n != NULL && es != UnknownEscape, "sanity"); 651 } 652 653 #endif // SHARE_OPTO_ESCAPE_HPP