1 /* 2 * Copyright (c) 2005, 2014, 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 #include "precompiled.hpp" 26 #include "ci/bcEscapeAnalyzer.hpp" 27 #include "compiler/compileLog.hpp" 28 #include "libadt/vectset.hpp" 29 #include "memory/allocation.hpp" 30 #include "opto/c2compiler.hpp" 31 #include "opto/callnode.hpp" 32 #include "opto/cfgnode.hpp" 33 #include "opto/compile.hpp" 34 #include "opto/escape.hpp" 35 #include "opto/phaseX.hpp" 36 #include "opto/movenode.hpp" 37 #include "opto/rootnode.hpp" 38 39 ConnectionGraph::ConnectionGraph(Compile * C, PhaseIterGVN *igvn) : 40 _nodes(C->comp_arena(), C->unique(), C->unique(), NULL), 41 _in_worklist(C->comp_arena()), 42 _next_pidx(0), 43 _collecting(true), 44 _verify(false), 45 _compile(C), 46 _igvn(igvn), 47 _node_map(C->comp_arena()) { 48 // Add unknown java object. 49 add_java_object(C->top(), PointsToNode::GlobalEscape); 50 phantom_obj = ptnode_adr(C->top()->_idx)->as_JavaObject(); 51 // Add ConP(#NULL) and ConN(#NULL) nodes. 52 Node* oop_null = igvn->zerocon(T_OBJECT); 53 assert(oop_null->_idx < nodes_size(), "should be created already"); 54 add_java_object(oop_null, PointsToNode::NoEscape); 55 null_obj = ptnode_adr(oop_null->_idx)->as_JavaObject(); 56 if (UseCompressedOops) { 57 Node* noop_null = igvn->zerocon(T_NARROWOOP); 58 assert(noop_null->_idx < nodes_size(), "should be created already"); 59 map_ideal_node(noop_null, null_obj); 60 } 61 _pcmp_neq = NULL; // Should be initialized 62 _pcmp_eq = NULL; 63 } 64 65 bool ConnectionGraph::has_candidates(Compile *C) { 66 // EA brings benefits only when the code has allocations and/or locks which 67 // are represented by ideal Macro nodes. 68 int cnt = C->macro_count(); 69 for (int i = 0; i < cnt; i++) { 70 Node *n = C->macro_node(i); 71 if (n->is_Allocate()) 72 return true; 73 if (n->is_Lock()) { 74 Node* obj = n->as_Lock()->obj_node()->uncast(); 75 if (!(obj->is_Parm() || obj->is_Con())) 76 return true; 77 } 78 if (n->is_CallStaticJava() && 79 n->as_CallStaticJava()->is_boxing_method()) { 80 return true; 81 } 82 } 83 return false; 84 } 85 86 void ConnectionGraph::do_analysis(Compile *C, PhaseIterGVN *igvn) { 87 Compile::TracePhase tp("escapeAnalysis", &Phase::timers[Phase::_t_escapeAnalysis]); 88 ResourceMark rm; 89 90 // Add ConP#NULL and ConN#NULL nodes before ConnectionGraph construction 91 // to create space for them in ConnectionGraph::_nodes[]. 92 Node* oop_null = igvn->zerocon(T_OBJECT); 93 Node* noop_null = igvn->zerocon(T_NARROWOOP); 94 ConnectionGraph* congraph = new(C->comp_arena()) ConnectionGraph(C, igvn); 95 // Perform escape analysis 96 if (congraph->compute_escape()) { 97 // There are non escaping objects. 98 C->set_congraph(congraph); 99 } 100 // Cleanup. 101 if (oop_null->outcnt() == 0) 102 igvn->hash_delete(oop_null); 103 if (noop_null->outcnt() == 0) 104 igvn->hash_delete(noop_null); 105 } 106 107 bool ConnectionGraph::compute_escape() { 108 Compile* C = _compile; 109 PhaseGVN* igvn = _igvn; 110 111 // Worklists used by EA. 112 Unique_Node_List delayed_worklist; 113 GrowableArray<Node*> alloc_worklist; 114 GrowableArray<Node*> ptr_cmp_worklist; 115 GrowableArray<Node*> storestore_worklist; 116 GrowableArray<PointsToNode*> ptnodes_worklist; 117 GrowableArray<JavaObjectNode*> java_objects_worklist; 118 GrowableArray<JavaObjectNode*> non_escaped_worklist; 119 GrowableArray<FieldNode*> oop_fields_worklist; 120 DEBUG_ONLY( GrowableArray<Node*> addp_worklist; ) 121 122 { Compile::TracePhase tp("connectionGraph", &Phase::timers[Phase::_t_connectionGraph]); 123 124 // 1. Populate Connection Graph (CG) with PointsTo nodes. 125 ideal_nodes.map(C->live_nodes(), NULL); // preallocate space 126 // Initialize worklist 127 if (C->root() != NULL) { 128 ideal_nodes.push(C->root()); 129 } 130 // Processed ideal nodes are unique on ideal_nodes list 131 // but several ideal nodes are mapped to the phantom_obj. 132 // To avoid duplicated entries on the following worklists 133 // add the phantom_obj only once to them. 134 ptnodes_worklist.append(phantom_obj); 135 java_objects_worklist.append(phantom_obj); 136 for( uint next = 0; next < ideal_nodes.size(); ++next ) { 137 Node* n = ideal_nodes.at(next); 138 // Create PointsTo nodes and add them to Connection Graph. Called 139 // only once per ideal node since ideal_nodes is Unique_Node list. 140 add_node_to_connection_graph(n, &delayed_worklist); 141 PointsToNode* ptn = ptnode_adr(n->_idx); 142 if (ptn != NULL && ptn != phantom_obj) { 143 ptnodes_worklist.append(ptn); 144 if (ptn->is_JavaObject()) { 145 java_objects_worklist.append(ptn->as_JavaObject()); 146 if ((n->is_Allocate() || n->is_CallStaticJava()) && 147 (ptn->escape_state() < PointsToNode::GlobalEscape)) { 148 // Only allocations and java static calls results are interesting. 149 non_escaped_worklist.append(ptn->as_JavaObject()); 150 } 151 } else if (ptn->is_Field() && ptn->as_Field()->is_oop()) { 152 oop_fields_worklist.append(ptn->as_Field()); 153 } 154 } 155 if (n->is_MergeMem()) { 156 // Collect all MergeMem nodes to add memory slices for 157 // scalar replaceable objects in split_unique_types(). 158 _mergemem_worklist.append(n->as_MergeMem()); 159 } else if (OptimizePtrCompare && n->is_Cmp() && 160 (n->Opcode() == Op_CmpP || n->Opcode() == Op_CmpN)) { 161 // Collect compare pointers nodes. 162 ptr_cmp_worklist.append(n); 163 } else if (n->is_MemBarStoreStore()) { 164 // Collect all MemBarStoreStore nodes so that depending on the 165 // escape status of the associated Allocate node some of them 166 // may be eliminated. 167 storestore_worklist.append(n); 168 } else if (n->is_MemBar() && (n->Opcode() == Op_MemBarRelease) && 169 (n->req() > MemBarNode::Precedent)) { 170 record_for_optimizer(n); 171 #ifdef ASSERT 172 } else if (n->is_AddP()) { 173 // Collect address nodes for graph verification. 174 addp_worklist.append(n); 175 #endif 176 } 177 for (DUIterator_Fast imax, i = n->fast_outs(imax); i < imax; i++) { 178 Node* m = n->fast_out(i); // Get user 179 ideal_nodes.push(m); 180 } 181 } 182 if (non_escaped_worklist.length() == 0) { 183 _collecting = false; 184 return false; // Nothing to do. 185 } 186 // Add final simple edges to graph. 187 while(delayed_worklist.size() > 0) { 188 Node* n = delayed_worklist.pop(); 189 add_final_edges(n); 190 } 191 int ptnodes_length = ptnodes_worklist.length(); 192 193 #ifdef ASSERT 194 if (VerifyConnectionGraph) { 195 // Verify that no new simple edges could be created and all 196 // local vars has edges. 197 _verify = true; 198 for (int next = 0; next < ptnodes_length; ++next) { 199 PointsToNode* ptn = ptnodes_worklist.at(next); 200 add_final_edges(ptn->ideal_node()); 201 if (ptn->is_LocalVar() && ptn->edge_count() == 0) { 202 ptn->dump(); 203 assert(ptn->as_LocalVar()->edge_count() > 0, "sanity"); 204 } 205 } 206 _verify = false; 207 } 208 #endif 209 210 // 2. Finish Graph construction by propagating references to all 211 // java objects through graph. 212 if (!complete_connection_graph(ptnodes_worklist, non_escaped_worklist, 213 java_objects_worklist, oop_fields_worklist)) { 214 // All objects escaped or hit time or iterations limits. 215 _collecting = false; 216 return false; 217 } 218 219 // 3. Adjust scalar_replaceable state of nonescaping objects and push 220 // scalar replaceable allocations on alloc_worklist for processing 221 // in split_unique_types(). 222 int non_escaped_length = non_escaped_worklist.length(); 223 for (int next = 0; next < non_escaped_length; next++) { 224 JavaObjectNode* ptn = non_escaped_worklist.at(next); 225 bool noescape = (ptn->escape_state() == PointsToNode::NoEscape); 226 Node* n = ptn->ideal_node(); 227 if (n->is_Allocate()) { 228 n->as_Allocate()->_is_non_escaping = noescape; 229 } 230 if (n->is_CallStaticJava()) { 231 n->as_CallStaticJava()->_is_non_escaping = noescape; 232 } 233 if (noescape && ptn->scalar_replaceable()) { 234 adjust_scalar_replaceable_state(ptn); 235 if (ptn->scalar_replaceable()) { 236 alloc_worklist.append(ptn->ideal_node()); 237 } 238 } 239 } 240 241 #ifdef ASSERT 242 if (VerifyConnectionGraph) { 243 // Verify that graph is complete - no new edges could be added or needed. 244 verify_connection_graph(ptnodes_worklist, non_escaped_worklist, 245 java_objects_worklist, addp_worklist); 246 } 247 assert(C->unique() == nodes_size(), "no new ideal nodes should be added during ConnectionGraph build"); 248 assert(null_obj->escape_state() == PointsToNode::NoEscape && 249 null_obj->edge_count() == 0 && 250 !null_obj->arraycopy_src() && 251 !null_obj->arraycopy_dst(), "sanity"); 252 #endif 253 254 _collecting = false; 255 256 } // TracePhase t3("connectionGraph") 257 258 // 4. Optimize ideal graph based on EA information. 259 bool has_non_escaping_obj = (non_escaped_worklist.length() > 0); 260 if (has_non_escaping_obj) { 261 optimize_ideal_graph(ptr_cmp_worklist, storestore_worklist); 262 } 263 264 #ifndef PRODUCT 265 if (PrintEscapeAnalysis) { 266 dump(ptnodes_worklist); // Dump ConnectionGraph 267 } 268 #endif 269 270 bool has_scalar_replaceable_candidates = (alloc_worklist.length() > 0); 271 #ifdef ASSERT 272 if (VerifyConnectionGraph) { 273 int alloc_length = alloc_worklist.length(); 274 for (int next = 0; next < alloc_length; ++next) { 275 Node* n = alloc_worklist.at(next); 276 PointsToNode* ptn = ptnode_adr(n->_idx); 277 assert(ptn->escape_state() == PointsToNode::NoEscape && ptn->scalar_replaceable(), "sanity"); 278 } 279 } 280 #endif 281 282 // 5. Separate memory graph for scalar replaceable allcations. 283 if (has_scalar_replaceable_candidates && 284 C->AliasLevel() >= 3 && EliminateAllocations) { 285 // Now use the escape information to create unique types for 286 // scalar replaceable objects. 287 split_unique_types(alloc_worklist); 288 if (C->failing()) return false; 289 C->print_method(PHASE_AFTER_EA, 2); 290 291 #ifdef ASSERT 292 } else if (Verbose && (PrintEscapeAnalysis || PrintEliminateAllocations)) { 293 tty->print("=== No allocations eliminated for "); 294 C->method()->print_short_name(); 295 if(!EliminateAllocations) { 296 tty->print(" since EliminateAllocations is off ==="); 297 } else if(!has_scalar_replaceable_candidates) { 298 tty->print(" since there are no scalar replaceable candidates ==="); 299 } else if(C->AliasLevel() < 3) { 300 tty->print(" since AliasLevel < 3 ==="); 301 } 302 tty->cr(); 303 #endif 304 } 305 return has_non_escaping_obj; 306 } 307 308 // Utility function for nodes that load an object 309 void ConnectionGraph::add_objload_to_connection_graph(Node *n, Unique_Node_List *delayed_worklist) { 310 // Using isa_ptr() instead of isa_oopptr() for LoadP and Phi because 311 // ThreadLocal has RawPtr type. 312 const Type* t = _igvn->type(n); 313 if (t->make_ptr() != NULL) { 314 Node* adr = n->in(MemNode::Address); 315 #ifdef ASSERT 316 if (!adr->is_AddP()) { 317 assert(_igvn->type(adr)->isa_rawptr(), "sanity"); 318 } else { 319 assert((ptnode_adr(adr->_idx) == NULL || 320 ptnode_adr(adr->_idx)->as_Field()->is_oop()), "sanity"); 321 } 322 #endif 323 add_local_var_and_edge(n, PointsToNode::NoEscape, 324 adr, delayed_worklist); 325 } 326 } 327 328 // Populate Connection Graph with PointsTo nodes and create simple 329 // connection graph edges. 330 void ConnectionGraph::add_node_to_connection_graph(Node *n, Unique_Node_List *delayed_worklist) { 331 assert(!_verify, "this method sould not be called for verification"); 332 PhaseGVN* igvn = _igvn; 333 uint n_idx = n->_idx; 334 PointsToNode* n_ptn = ptnode_adr(n_idx); 335 if (n_ptn != NULL) 336 return; // No need to redefine PointsTo node during first iteration. 337 338 if (n->is_Call()) { 339 // Arguments to allocation and locking don't escape. 340 if (n->is_AbstractLock()) { 341 // Put Lock and Unlock nodes on IGVN worklist to process them during 342 // first IGVN optimization when escape information is still available. 343 record_for_optimizer(n); 344 } else if (n->is_Allocate()) { 345 add_call_node(n->as_Call()); 346 record_for_optimizer(n); 347 } else { 348 if (n->is_CallStaticJava()) { 349 const char* name = n->as_CallStaticJava()->_name; 350 if (name != NULL && strcmp(name, "uncommon_trap") == 0) 351 return; // Skip uncommon traps 352 } 353 // Don't mark as processed since call's arguments have to be processed. 354 delayed_worklist->push(n); 355 // Check if a call returns an object. 356 if ((n->as_Call()->returns_pointer() && 357 n->as_Call()->proj_out(TypeFunc::Parms) != NULL) || 358 (n->is_CallStaticJava() && 359 n->as_CallStaticJava()->is_boxing_method())) { 360 add_call_node(n->as_Call()); 361 } 362 } 363 return; 364 } 365 // Put this check here to process call arguments since some call nodes 366 // point to phantom_obj. 367 if (n_ptn == phantom_obj || n_ptn == null_obj) 368 return; // Skip predefined nodes. 369 370 int opcode = n->Opcode(); 371 switch (opcode) { 372 case Op_AddP: { 373 Node* base = get_addp_base(n); 374 PointsToNode* ptn_base = ptnode_adr(base->_idx); 375 // Field nodes are created for all field types. They are used in 376 // adjust_scalar_replaceable_state() and split_unique_types(). 377 // Note, non-oop fields will have only base edges in Connection 378 // Graph because such fields are not used for oop loads and stores. 379 int offset = address_offset(n, igvn); 380 add_field(n, PointsToNode::NoEscape, offset); 381 if (ptn_base == NULL) { 382 delayed_worklist->push(n); // Process it later. 383 } else { 384 n_ptn = ptnode_adr(n_idx); 385 add_base(n_ptn->as_Field(), ptn_base); 386 } 387 break; 388 } 389 case Op_CastX2P: { 390 map_ideal_node(n, phantom_obj); 391 break; 392 } 393 case Op_CastPP: 394 case Op_CheckCastPP: 395 case Op_EncodeP: 396 case Op_DecodeN: 397 case Op_EncodePKlass: 398 case Op_DecodeNKlass: { 399 add_local_var_and_edge(n, PointsToNode::NoEscape, 400 n->in(1), delayed_worklist); 401 break; 402 } 403 case Op_CMoveP: { 404 add_local_var(n, PointsToNode::NoEscape); 405 // Do not add edges during first iteration because some could be 406 // not defined yet. 407 delayed_worklist->push(n); 408 break; 409 } 410 case Op_ConP: 411 case Op_ConN: 412 case Op_ConNKlass: { 413 // assume all oop constants globally escape except for null 414 PointsToNode::EscapeState es; 415 const Type* t = igvn->type(n); 416 if (t == TypePtr::NULL_PTR || t == TypeNarrowOop::NULL_PTR) { 417 es = PointsToNode::NoEscape; 418 } else { 419 es = PointsToNode::GlobalEscape; 420 } 421 add_java_object(n, es); 422 break; 423 } 424 case Op_CreateEx: { 425 // assume that all exception objects globally escape 426 map_ideal_node(n, phantom_obj); 427 break; 428 } 429 case Op_LoadKlass: 430 case Op_LoadNKlass: { 431 // Unknown class is loaded 432 map_ideal_node(n, phantom_obj); 433 break; 434 } 435 case Op_LoadP: 436 case Op_LoadN: 437 case Op_LoadPLocked: { 438 add_objload_to_connection_graph(n, delayed_worklist); 439 break; 440 } 441 case Op_Parm: { 442 map_ideal_node(n, phantom_obj); 443 break; 444 } 445 case Op_PartialSubtypeCheck: { 446 // Produces Null or notNull and is used in only in CmpP so 447 // phantom_obj could be used. 448 map_ideal_node(n, phantom_obj); // Result is unknown 449 break; 450 } 451 case Op_Phi: { 452 // Using isa_ptr() instead of isa_oopptr() for LoadP and Phi because 453 // ThreadLocal has RawPtr type. 454 const Type* t = n->as_Phi()->type(); 455 if (t->make_ptr() != NULL) { 456 add_local_var(n, PointsToNode::NoEscape); 457 // Do not add edges during first iteration because some could be 458 // not defined yet. 459 delayed_worklist->push(n); 460 } 461 break; 462 } 463 case Op_Proj: { 464 // we are only interested in the oop result projection from a call 465 if (n->as_Proj()->_con == TypeFunc::Parms && n->in(0)->is_Call() && 466 n->in(0)->as_Call()->returns_pointer()) { 467 add_local_var_and_edge(n, PointsToNode::NoEscape, 468 n->in(0), delayed_worklist); 469 } 470 break; 471 } 472 case Op_Rethrow: // Exception object escapes 473 case Op_Return: { 474 if (n->req() > TypeFunc::Parms && 475 igvn->type(n->in(TypeFunc::Parms))->isa_oopptr()) { 476 // Treat Return value as LocalVar with GlobalEscape escape state. 477 add_local_var_and_edge(n, PointsToNode::GlobalEscape, 478 n->in(TypeFunc::Parms), delayed_worklist); 479 } 480 break; 481 } 482 case Op_GetAndSetP: 483 case Op_GetAndSetN: { 484 add_objload_to_connection_graph(n, delayed_worklist); 485 // fallthrough 486 } 487 case Op_StoreP: 488 case Op_StoreN: 489 case Op_StoreNKlass: 490 case Op_StorePConditional: 491 case Op_CompareAndSwapP: 492 case Op_CompareAndSwapN: { 493 Node* adr = n->in(MemNode::Address); 494 const Type *adr_type = igvn->type(adr); 495 adr_type = adr_type->make_ptr(); 496 if (adr_type == NULL) { 497 break; // skip dead nodes 498 } 499 if (adr_type->isa_oopptr() || 500 (opcode == Op_StoreP || opcode == Op_StoreN || opcode == Op_StoreNKlass) && 501 (adr_type == TypeRawPtr::NOTNULL && 502 adr->in(AddPNode::Address)->is_Proj() && 503 adr->in(AddPNode::Address)->in(0)->is_Allocate())) { 504 delayed_worklist->push(n); // Process it later. 505 #ifdef ASSERT 506 assert(adr->is_AddP(), "expecting an AddP"); 507 if (adr_type == TypeRawPtr::NOTNULL) { 508 // Verify a raw address for a store captured by Initialize node. 509 int offs = (int)igvn->find_intptr_t_con(adr->in(AddPNode::Offset), Type::OffsetBot); 510 assert(offs != Type::OffsetBot, "offset must be a constant"); 511 } 512 #endif 513 } else { 514 // Ignore copy the displaced header to the BoxNode (OSR compilation). 515 if (adr->is_BoxLock()) 516 break; 517 // Stored value escapes in unsafe access. 518 if ((opcode == Op_StoreP) && (adr_type == TypeRawPtr::BOTTOM)) { 519 // Pointer stores in G1 barriers looks like unsafe access. 520 // Ignore such stores to be able scalar replace non-escaping 521 // allocations. 522 if (UseG1GC && adr->is_AddP()) { 523 Node* base = get_addp_base(adr); 524 if (base->Opcode() == Op_LoadP && 525 base->in(MemNode::Address)->is_AddP()) { 526 adr = base->in(MemNode::Address); 527 Node* tls = get_addp_base(adr); 528 if (tls->Opcode() == Op_ThreadLocal) { 529 int offs = (int)igvn->find_intptr_t_con(adr->in(AddPNode::Offset), Type::OffsetBot); 530 if (offs == in_bytes(JavaThread::satb_mark_queue_offset() + 531 PtrQueue::byte_offset_of_buf())) { 532 break; // G1 pre barier previous oop value store. 533 } 534 if (offs == in_bytes(JavaThread::dirty_card_queue_offset() + 535 PtrQueue::byte_offset_of_buf())) { 536 break; // G1 post barier card address store. 537 } 538 } 539 } 540 } 541 delayed_worklist->push(n); // Process unsafe access later. 542 break; 543 } 544 #ifdef ASSERT 545 n->dump(1); 546 assert(false, "not unsafe or G1 barrier raw StoreP"); 547 #endif 548 } 549 break; 550 } 551 case Op_AryEq: 552 case Op_StrComp: 553 case Op_StrEquals: 554 case Op_StrIndexOf: 555 case Op_EncodeISOArray: { 556 add_local_var(n, PointsToNode::ArgEscape); 557 delayed_worklist->push(n); // Process it later. 558 break; 559 } 560 case Op_ThreadLocal: { 561 add_java_object(n, PointsToNode::ArgEscape); 562 break; 563 } 564 default: 565 ; // Do nothing for nodes not related to EA. 566 } 567 return; 568 } 569 570 #ifdef ASSERT 571 #define ELSE_FAIL(name) \ 572 /* Should not be called for not pointer type. */ \ 573 n->dump(1); \ 574 assert(false, name); \ 575 break; 576 #else 577 #define ELSE_FAIL(name) \ 578 break; 579 #endif 580 581 // Add final simple edges to graph. 582 void ConnectionGraph::add_final_edges(Node *n) { 583 PointsToNode* n_ptn = ptnode_adr(n->_idx); 584 #ifdef ASSERT 585 if (_verify && n_ptn->is_JavaObject()) 586 return; // This method does not change graph for JavaObject. 587 #endif 588 589 if (n->is_Call()) { 590 process_call_arguments(n->as_Call()); 591 return; 592 } 593 assert(n->is_Store() || n->is_LoadStore() || 594 (n_ptn != NULL) && (n_ptn->ideal_node() != NULL), 595 "node should be registered already"); 596 int opcode = n->Opcode(); 597 switch (opcode) { 598 case Op_AddP: { 599 Node* base = get_addp_base(n); 600 PointsToNode* ptn_base = ptnode_adr(base->_idx); 601 assert(ptn_base != NULL, "field's base should be registered"); 602 add_base(n_ptn->as_Field(), ptn_base); 603 break; 604 } 605 case Op_CastPP: 606 case Op_CheckCastPP: 607 case Op_EncodeP: 608 case Op_DecodeN: 609 case Op_EncodePKlass: 610 case Op_DecodeNKlass: { 611 add_local_var_and_edge(n, PointsToNode::NoEscape, 612 n->in(1), NULL); 613 break; 614 } 615 case Op_CMoveP: { 616 for (uint i = CMoveNode::IfFalse; i < n->req(); i++) { 617 Node* in = n->in(i); 618 if (in == NULL) 619 continue; // ignore NULL 620 Node* uncast_in = in->uncast(); 621 if (uncast_in->is_top() || uncast_in == n) 622 continue; // ignore top or inputs which go back this node 623 PointsToNode* ptn = ptnode_adr(in->_idx); 624 assert(ptn != NULL, "node should be registered"); 625 add_edge(n_ptn, ptn); 626 } 627 break; 628 } 629 case Op_LoadP: 630 case Op_LoadN: 631 case Op_LoadPLocked: { 632 // Using isa_ptr() instead of isa_oopptr() for LoadP and Phi because 633 // ThreadLocal has RawPtr type. 634 const Type* t = _igvn->type(n); 635 if (t->make_ptr() != NULL) { 636 Node* adr = n->in(MemNode::Address); 637 add_local_var_and_edge(n, PointsToNode::NoEscape, adr, NULL); 638 break; 639 } 640 ELSE_FAIL("Op_LoadP"); 641 } 642 case Op_Phi: { 643 // Using isa_ptr() instead of isa_oopptr() for LoadP and Phi because 644 // ThreadLocal has RawPtr type. 645 const Type* t = n->as_Phi()->type(); 646 if (t->make_ptr() != NULL) { 647 for (uint i = 1; i < n->req(); i++) { 648 Node* in = n->in(i); 649 if (in == NULL) 650 continue; // ignore NULL 651 Node* uncast_in = in->uncast(); 652 if (uncast_in->is_top() || uncast_in == n) 653 continue; // ignore top or inputs which go back this node 654 PointsToNode* ptn = ptnode_adr(in->_idx); 655 assert(ptn != NULL, "node should be registered"); 656 add_edge(n_ptn, ptn); 657 } 658 break; 659 } 660 ELSE_FAIL("Op_Phi"); 661 } 662 case Op_Proj: { 663 // we are only interested in the oop result projection from a call 664 if (n->as_Proj()->_con == TypeFunc::Parms && n->in(0)->is_Call() && 665 n->in(0)->as_Call()->returns_pointer()) { 666 add_local_var_and_edge(n, PointsToNode::NoEscape, n->in(0), NULL); 667 break; 668 } 669 ELSE_FAIL("Op_Proj"); 670 } 671 case Op_Rethrow: // Exception object escapes 672 case Op_Return: { 673 if (n->req() > TypeFunc::Parms && 674 _igvn->type(n->in(TypeFunc::Parms))->isa_oopptr()) { 675 // Treat Return value as LocalVar with GlobalEscape escape state. 676 add_local_var_and_edge(n, PointsToNode::GlobalEscape, 677 n->in(TypeFunc::Parms), NULL); 678 break; 679 } 680 ELSE_FAIL("Op_Return"); 681 } 682 case Op_StoreP: 683 case Op_StoreN: 684 case Op_StoreNKlass: 685 case Op_StorePConditional: 686 case Op_CompareAndSwapP: 687 case Op_CompareAndSwapN: 688 case Op_GetAndSetP: 689 case Op_GetAndSetN: { 690 Node* adr = n->in(MemNode::Address); 691 const Type *adr_type = _igvn->type(adr); 692 adr_type = adr_type->make_ptr(); 693 #ifdef ASSERT 694 if (adr_type == NULL) { 695 n->dump(1); 696 assert(adr_type != NULL, "dead node should not be on list"); 697 break; 698 } 699 #endif 700 if (opcode == Op_GetAndSetP || opcode == Op_GetAndSetN) { 701 add_local_var_and_edge(n, PointsToNode::NoEscape, adr, NULL); 702 } 703 if (adr_type->isa_oopptr() || 704 (opcode == Op_StoreP || opcode == Op_StoreN || opcode == Op_StoreNKlass) && 705 (adr_type == TypeRawPtr::NOTNULL && 706 adr->in(AddPNode::Address)->is_Proj() && 707 adr->in(AddPNode::Address)->in(0)->is_Allocate())) { 708 // Point Address to Value 709 PointsToNode* adr_ptn = ptnode_adr(adr->_idx); 710 assert(adr_ptn != NULL && 711 adr_ptn->as_Field()->is_oop(), "node should be registered"); 712 Node *val = n->in(MemNode::ValueIn); 713 PointsToNode* ptn = ptnode_adr(val->_idx); 714 assert(ptn != NULL, "node should be registered"); 715 add_edge(adr_ptn, ptn); 716 break; 717 } else if ((opcode == Op_StoreP) && (adr_type == TypeRawPtr::BOTTOM)) { 718 // Stored value escapes in unsafe access. 719 Node *val = n->in(MemNode::ValueIn); 720 PointsToNode* ptn = ptnode_adr(val->_idx); 721 assert(ptn != NULL, "node should be registered"); 722 set_escape_state(ptn, PointsToNode::GlobalEscape); 723 // Add edge to object for unsafe access with offset. 724 PointsToNode* adr_ptn = ptnode_adr(adr->_idx); 725 assert(adr_ptn != NULL, "node should be registered"); 726 if (adr_ptn->is_Field()) { 727 assert(adr_ptn->as_Field()->is_oop(), "should be oop field"); 728 add_edge(adr_ptn, ptn); 729 } 730 break; 731 } 732 ELSE_FAIL("Op_StoreP"); 733 } 734 case Op_AryEq: 735 case Op_StrComp: 736 case Op_StrEquals: 737 case Op_StrIndexOf: 738 case Op_EncodeISOArray: { 739 // char[] arrays passed to string intrinsic do not escape but 740 // they are not scalar replaceable. Adjust escape state for them. 741 // Start from in(2) edge since in(1) is memory edge. 742 for (uint i = 2; i < n->req(); i++) { 743 Node* adr = n->in(i); 744 const Type* at = _igvn->type(adr); 745 if (!adr->is_top() && at->isa_ptr()) { 746 assert(at == Type::TOP || at == TypePtr::NULL_PTR || 747 at->isa_ptr() != NULL, "expecting a pointer"); 748 if (adr->is_AddP()) { 749 adr = get_addp_base(adr); 750 } 751 PointsToNode* ptn = ptnode_adr(adr->_idx); 752 assert(ptn != NULL, "node should be registered"); 753 add_edge(n_ptn, ptn); 754 } 755 } 756 break; 757 } 758 default: { 759 // This method should be called only for EA specific nodes which may 760 // miss some edges when they were created. 761 #ifdef ASSERT 762 n->dump(1); 763 #endif 764 guarantee(false, "unknown node"); 765 } 766 } 767 return; 768 } 769 770 void ConnectionGraph::add_call_node(CallNode* call) { 771 assert(call->returns_pointer(), "only for call which returns pointer"); 772 uint call_idx = call->_idx; 773 if (call->is_Allocate()) { 774 Node* k = call->in(AllocateNode::KlassNode); 775 const TypeKlassPtr* kt = k->bottom_type()->isa_klassptr(); 776 assert(kt != NULL, "TypeKlassPtr required."); 777 ciKlass* cik = kt->klass(); 778 PointsToNode::EscapeState es = PointsToNode::NoEscape; 779 bool scalar_replaceable = true; 780 if (call->is_AllocateArray()) { 781 if (!cik->is_array_klass()) { // StressReflectiveCode 782 es = PointsToNode::GlobalEscape; 783 } else { 784 int length = call->in(AllocateNode::ALength)->find_int_con(-1); 785 if (length < 0 || length > EliminateAllocationArraySizeLimit) { 786 // Not scalar replaceable if the length is not constant or too big. 787 scalar_replaceable = false; 788 } 789 } 790 } else { // Allocate instance 791 if (cik->is_subclass_of(_compile->env()->Thread_klass()) || 792 cik->is_subclass_of(_compile->env()->Reference_klass()) || 793 !cik->is_instance_klass() || // StressReflectiveCode 794 cik->as_instance_klass()->has_finalizer()) { 795 es = PointsToNode::GlobalEscape; 796 } 797 } 798 add_java_object(call, es); 799 PointsToNode* ptn = ptnode_adr(call_idx); 800 if (!scalar_replaceable && ptn->scalar_replaceable()) { 801 ptn->set_scalar_replaceable(false); 802 } 803 } else if (call->is_CallStaticJava()) { 804 // Call nodes could be different types: 805 // 806 // 1. CallDynamicJavaNode (what happened during call is unknown): 807 // 808 // - mapped to GlobalEscape JavaObject node if oop is returned; 809 // 810 // - all oop arguments are escaping globally; 811 // 812 // 2. CallStaticJavaNode (execute bytecode analysis if possible): 813 // 814 // - the same as CallDynamicJavaNode if can't do bytecode analysis; 815 // 816 // - mapped to GlobalEscape JavaObject node if unknown oop is returned; 817 // - mapped to NoEscape JavaObject node if non-escaping object allocated 818 // during call is returned; 819 // - mapped to ArgEscape LocalVar node pointed to object arguments 820 // which are returned and does not escape during call; 821 // 822 // - oop arguments escaping status is defined by bytecode analysis; 823 // 824 // For a static call, we know exactly what method is being called. 825 // Use bytecode estimator to record whether the call's return value escapes. 826 ciMethod* meth = call->as_CallJava()->method(); 827 if (meth == NULL) { 828 const char* name = call->as_CallStaticJava()->_name; 829 assert(strncmp(name, "_multianewarray", 15) == 0, "TODO: add failed case check"); 830 // Returns a newly allocated unescaped object. 831 add_java_object(call, PointsToNode::NoEscape); 832 ptnode_adr(call_idx)->set_scalar_replaceable(false); 833 } else if (meth->is_boxing_method()) { 834 // Returns boxing object 835 PointsToNode::EscapeState es; 836 vmIntrinsics::ID intr = meth->intrinsic_id(); 837 if (intr == vmIntrinsics::_floatValue || intr == vmIntrinsics::_doubleValue) { 838 // It does not escape if object is always allocated. 839 es = PointsToNode::NoEscape; 840 } else { 841 // It escapes globally if object could be loaded from cache. 842 es = PointsToNode::GlobalEscape; 843 } 844 add_java_object(call, es); 845 } else { 846 BCEscapeAnalyzer* call_analyzer = meth->get_bcea(); 847 call_analyzer->copy_dependencies(_compile->dependencies()); 848 if (call_analyzer->is_return_allocated()) { 849 // Returns a newly allocated unescaped object, simply 850 // update dependency information. 851 // Mark it as NoEscape so that objects referenced by 852 // it's fields will be marked as NoEscape at least. 853 add_java_object(call, PointsToNode::NoEscape); 854 ptnode_adr(call_idx)->set_scalar_replaceable(false); 855 } else { 856 // Determine whether any arguments are returned. 857 const TypeTuple* d = call->tf()->domain(); 858 bool ret_arg = false; 859 for (uint i = TypeFunc::Parms; i < d->cnt(); i++) { 860 if (d->field_at(i)->isa_ptr() != NULL && 861 call_analyzer->is_arg_returned(i - TypeFunc::Parms)) { 862 ret_arg = true; 863 break; 864 } 865 } 866 if (ret_arg) { 867 add_local_var(call, PointsToNode::ArgEscape); 868 } else { 869 // Returns unknown object. 870 map_ideal_node(call, phantom_obj); 871 } 872 } 873 } 874 } else { 875 // An other type of call, assume the worst case: 876 // returned value is unknown and globally escapes. 877 assert(call->Opcode() == Op_CallDynamicJava, "add failed case check"); 878 map_ideal_node(call, phantom_obj); 879 } 880 } 881 882 void ConnectionGraph::process_call_arguments(CallNode *call) { 883 bool is_arraycopy = false; 884 switch (call->Opcode()) { 885 #ifdef ASSERT 886 case Op_Allocate: 887 case Op_AllocateArray: 888 case Op_Lock: 889 case Op_Unlock: 890 assert(false, "should be done already"); 891 break; 892 #endif 893 case Op_ArrayCopy: 894 case Op_CallLeafNoFP: 895 // Most array copies are ArrayCopy nodes at this point but there 896 // are still a few direct calls to the copy subroutines (See 897 // PhaseStringOpts::copy_string()) 898 is_arraycopy = (call->Opcode() == Op_ArrayCopy) || 899 (call->as_CallLeaf()->_name != NULL && 900 strstr(call->as_CallLeaf()->_name, "arraycopy") != 0); 901 // fall through 902 case Op_CallLeaf: { 903 // Stub calls, objects do not escape but they are not scale replaceable. 904 // Adjust escape state for outgoing arguments. 905 const TypeTuple * d = call->tf()->domain(); 906 bool src_has_oops = false; 907 for (uint i = TypeFunc::Parms; i < d->cnt(); i++) { 908 const Type* at = d->field_at(i); 909 Node *arg = call->in(i); 910 if (arg == NULL) { 911 continue; 912 } 913 const Type *aat = _igvn->type(arg); 914 if (arg->is_top() || !at->isa_ptr() || !aat->isa_ptr()) 915 continue; 916 if (arg->is_AddP()) { 917 // 918 // The inline_native_clone() case when the arraycopy stub is called 919 // after the allocation before Initialize and CheckCastPP nodes. 920 // Or normal arraycopy for object arrays case. 921 // 922 // Set AddP's base (Allocate) as not scalar replaceable since 923 // pointer to the base (with offset) is passed as argument. 924 // 925 arg = get_addp_base(arg); 926 } 927 PointsToNode* arg_ptn = ptnode_adr(arg->_idx); 928 assert(arg_ptn != NULL, "should be registered"); 929 PointsToNode::EscapeState arg_esc = arg_ptn->escape_state(); 930 if (is_arraycopy || arg_esc < PointsToNode::ArgEscape) { 931 assert(aat == Type::TOP || aat == TypePtr::NULL_PTR || 932 aat->isa_ptr() != NULL, "expecting an Ptr"); 933 bool arg_has_oops = aat->isa_oopptr() && 934 (aat->isa_oopptr()->klass() == NULL || aat->isa_instptr() || 935 (aat->isa_aryptr() && aat->isa_aryptr()->klass()->is_obj_array_klass())); 936 if (i == TypeFunc::Parms) { 937 src_has_oops = arg_has_oops; 938 } 939 // 940 // src or dst could be j.l.Object when other is basic type array: 941 // 942 // arraycopy(char[],0,Object*,0,size); 943 // arraycopy(Object*,0,char[],0,size); 944 // 945 // Don't add edges in such cases. 946 // 947 bool arg_is_arraycopy_dest = src_has_oops && is_arraycopy && 948 arg_has_oops && (i > TypeFunc::Parms); 949 #ifdef ASSERT 950 if (!(is_arraycopy || 951 (call->as_CallLeaf()->_name != NULL && 952 (strcmp(call->as_CallLeaf()->_name, "g1_wb_pre") == 0 || 953 strcmp(call->as_CallLeaf()->_name, "g1_wb_post") == 0 || 954 strcmp(call->as_CallLeaf()->_name, "updateBytesCRC32") == 0 || 955 strcmp(call->as_CallLeaf()->_name, "aescrypt_encryptBlock") == 0 || 956 strcmp(call->as_CallLeaf()->_name, "aescrypt_decryptBlock") == 0 || 957 strcmp(call->as_CallLeaf()->_name, "cipherBlockChaining_encryptAESCrypt") == 0 || 958 strcmp(call->as_CallLeaf()->_name, "cipherBlockChaining_decryptAESCrypt") == 0 || 959 strcmp(call->as_CallLeaf()->_name, "sha1_implCompress") == 0 || 960 strcmp(call->as_CallLeaf()->_name, "sha1_implCompressMB") == 0 || 961 strcmp(call->as_CallLeaf()->_name, "sha256_implCompress") == 0 || 962 strcmp(call->as_CallLeaf()->_name, "sha256_implCompressMB") == 0 || 963 strcmp(call->as_CallLeaf()->_name, "sha512_implCompress") == 0 || 964 strcmp(call->as_CallLeaf()->_name, "sha512_implCompressMB") == 0 || 965 strcmp(call->as_CallLeaf()->_name, "multiplyToLen") == 0) 966 ))) { 967 call->dump(); 968 fatal(err_msg_res("EA unexpected CallLeaf %s", call->as_CallLeaf()->_name)); 969 } 970 #endif 971 // Always process arraycopy's destination object since 972 // we need to add all possible edges to references in 973 // source object. 974 if (arg_esc >= PointsToNode::ArgEscape && 975 !arg_is_arraycopy_dest) { 976 continue; 977 } 978 set_escape_state(arg_ptn, PointsToNode::ArgEscape); 979 if (arg_is_arraycopy_dest) { 980 Node* src = call->in(TypeFunc::Parms); 981 if (src->is_AddP()) { 982 src = get_addp_base(src); 983 } 984 PointsToNode* src_ptn = ptnode_adr(src->_idx); 985 assert(src_ptn != NULL, "should be registered"); 986 if (arg_ptn != src_ptn) { 987 // Special arraycopy edge: 988 // A destination object's field can't have the source object 989 // as base since objects escape states are not related. 990 // Only escape state of destination object's fields affects 991 // escape state of fields in source object. 992 add_arraycopy(call, PointsToNode::ArgEscape, src_ptn, arg_ptn); 993 } 994 } 995 } 996 } 997 break; 998 } 999 case Op_CallStaticJava: { 1000 // For a static call, we know exactly what method is being called. 1001 // Use bytecode estimator to record the call's escape affects 1002 #ifdef ASSERT 1003 const char* name = call->as_CallStaticJava()->_name; 1004 assert((name == NULL || strcmp(name, "uncommon_trap") != 0), "normal calls only"); 1005 #endif 1006 ciMethod* meth = call->as_CallJava()->method(); 1007 if ((meth != NULL) && meth->is_boxing_method()) { 1008 break; // Boxing methods do not modify any oops. 1009 } 1010 BCEscapeAnalyzer* call_analyzer = (meth !=NULL) ? meth->get_bcea() : NULL; 1011 // fall-through if not a Java method or no analyzer information 1012 if (call_analyzer != NULL) { 1013 PointsToNode* call_ptn = ptnode_adr(call->_idx); 1014 const TypeTuple* d = call->tf()->domain(); 1015 for (uint i = TypeFunc::Parms; i < d->cnt(); i++) { 1016 const Type* at = d->field_at(i); 1017 int k = i - TypeFunc::Parms; 1018 Node* arg = call->in(i); 1019 PointsToNode* arg_ptn = ptnode_adr(arg->_idx); 1020 if (at->isa_ptr() != NULL && 1021 call_analyzer->is_arg_returned(k)) { 1022 // The call returns arguments. 1023 if (call_ptn != NULL) { // Is call's result used? 1024 assert(call_ptn->is_LocalVar(), "node should be registered"); 1025 assert(arg_ptn != NULL, "node should be registered"); 1026 add_edge(call_ptn, arg_ptn); 1027 } 1028 } 1029 if (at->isa_oopptr() != NULL && 1030 arg_ptn->escape_state() < PointsToNode::GlobalEscape) { 1031 if (!call_analyzer->is_arg_stack(k)) { 1032 // The argument global escapes 1033 set_escape_state(arg_ptn, PointsToNode::GlobalEscape); 1034 } else { 1035 set_escape_state(arg_ptn, PointsToNode::ArgEscape); 1036 if (!call_analyzer->is_arg_local(k)) { 1037 // The argument itself doesn't escape, but any fields might 1038 set_fields_escape_state(arg_ptn, PointsToNode::GlobalEscape); 1039 } 1040 } 1041 } 1042 } 1043 if (call_ptn != NULL && call_ptn->is_LocalVar()) { 1044 // The call returns arguments. 1045 assert(call_ptn->edge_count() > 0, "sanity"); 1046 if (!call_analyzer->is_return_local()) { 1047 // Returns also unknown object. 1048 add_edge(call_ptn, phantom_obj); 1049 } 1050 } 1051 break; 1052 } 1053 } 1054 default: { 1055 // Fall-through here if not a Java method or no analyzer information 1056 // or some other type of call, assume the worst case: all arguments 1057 // globally escape. 1058 const TypeTuple* d = call->tf()->domain(); 1059 for (uint i = TypeFunc::Parms; i < d->cnt(); i++) { 1060 const Type* at = d->field_at(i); 1061 if (at->isa_oopptr() != NULL) { 1062 Node* arg = call->in(i); 1063 if (arg->is_AddP()) { 1064 arg = get_addp_base(arg); 1065 } 1066 assert(ptnode_adr(arg->_idx) != NULL, "should be defined already"); 1067 set_escape_state(ptnode_adr(arg->_idx), PointsToNode::GlobalEscape); 1068 } 1069 } 1070 } 1071 } 1072 } 1073 1074 1075 // Finish Graph construction. 1076 bool ConnectionGraph::complete_connection_graph( 1077 GrowableArray<PointsToNode*>& ptnodes_worklist, 1078 GrowableArray<JavaObjectNode*>& non_escaped_worklist, 1079 GrowableArray<JavaObjectNode*>& java_objects_worklist, 1080 GrowableArray<FieldNode*>& oop_fields_worklist) { 1081 // Normally only 1-3 passes needed to build Connection Graph depending 1082 // on graph complexity. Observed 8 passes in jvm2008 compiler.compiler. 1083 // Set limit to 20 to catch situation when something did go wrong and 1084 // bailout Escape Analysis. 1085 // Also limit build time to 20 sec (60 in debug VM), EscapeAnalysisTimeout flag. 1086 #define CG_BUILD_ITER_LIMIT 20 1087 1088 // Propagate GlobalEscape and ArgEscape escape states and check that 1089 // we still have non-escaping objects. The method pushs on _worklist 1090 // Field nodes which reference phantom_object. 1091 if (!find_non_escaped_objects(ptnodes_worklist, non_escaped_worklist)) { 1092 return false; // Nothing to do. 1093 } 1094 // Now propagate references to all JavaObject nodes. 1095 int java_objects_length = java_objects_worklist.length(); 1096 elapsedTimer time; 1097 bool timeout = false; 1098 int new_edges = 1; 1099 int iterations = 0; 1100 do { 1101 while ((new_edges > 0) && 1102 (iterations++ < CG_BUILD_ITER_LIMIT)) { 1103 double start_time = time.seconds(); 1104 time.start(); 1105 new_edges = 0; 1106 // Propagate references to phantom_object for nodes pushed on _worklist 1107 // by find_non_escaped_objects() and find_field_value(). 1108 new_edges += add_java_object_edges(phantom_obj, false); 1109 for (int next = 0; next < java_objects_length; ++next) { 1110 JavaObjectNode* ptn = java_objects_worklist.at(next); 1111 new_edges += add_java_object_edges(ptn, true); 1112 1113 #define SAMPLE_SIZE 4 1114 if ((next % SAMPLE_SIZE) == 0) { 1115 // Each 4 iterations calculate how much time it will take 1116 // to complete graph construction. 1117 time.stop(); 1118 double stop_time = time.seconds(); 1119 double time_per_iter = (stop_time - start_time) / (double)SAMPLE_SIZE; 1120 double time_until_end = time_per_iter * (double)(java_objects_length - next); 1121 if ((start_time + time_until_end) >= EscapeAnalysisTimeout) { 1122 timeout = true; 1123 break; // Timeout 1124 } 1125 start_time = stop_time; 1126 time.start(); 1127 } 1128 #undef SAMPLE_SIZE 1129 1130 } 1131 if (timeout) break; 1132 if (new_edges > 0) { 1133 // Update escape states on each iteration if graph was updated. 1134 if (!find_non_escaped_objects(ptnodes_worklist, non_escaped_worklist)) { 1135 return false; // Nothing to do. 1136 } 1137 } 1138 time.stop(); 1139 if (time.seconds() >= EscapeAnalysisTimeout) { 1140 timeout = true; 1141 break; 1142 } 1143 } 1144 if ((iterations < CG_BUILD_ITER_LIMIT) && !timeout) { 1145 time.start(); 1146 // Find fields which have unknown value. 1147 int fields_length = oop_fields_worklist.length(); 1148 for (int next = 0; next < fields_length; next++) { 1149 FieldNode* field = oop_fields_worklist.at(next); 1150 if (field->edge_count() == 0) { 1151 new_edges += find_field_value(field); 1152 // This code may added new edges to phantom_object. 1153 // Need an other cycle to propagate references to phantom_object. 1154 } 1155 } 1156 time.stop(); 1157 if (time.seconds() >= EscapeAnalysisTimeout) { 1158 timeout = true; 1159 break; 1160 } 1161 } else { 1162 new_edges = 0; // Bailout 1163 } 1164 } while (new_edges > 0); 1165 1166 // Bailout if passed limits. 1167 if ((iterations >= CG_BUILD_ITER_LIMIT) || timeout) { 1168 Compile* C = _compile; 1169 if (C->log() != NULL) { 1170 C->log()->begin_elem("connectionGraph_bailout reason='reached "); 1171 C->log()->text("%s", timeout ? "time" : "iterations"); 1172 C->log()->end_elem(" limit'"); 1173 } 1174 assert(ExitEscapeAnalysisOnTimeout, err_msg_res("infinite EA connection graph build (%f sec, %d iterations) with %d nodes and worklist size %d", 1175 time.seconds(), iterations, nodes_size(), ptnodes_worklist.length())); 1176 // Possible infinite build_connection_graph loop, 1177 // bailout (no changes to ideal graph were made). 1178 return false; 1179 } 1180 #ifdef ASSERT 1181 if (Verbose && PrintEscapeAnalysis) { 1182 tty->print_cr("EA: %d iterations to build connection graph with %d nodes and worklist size %d", 1183 iterations, nodes_size(), ptnodes_worklist.length()); 1184 } 1185 #endif 1186 1187 #undef CG_BUILD_ITER_LIMIT 1188 1189 // Find fields initialized by NULL for non-escaping Allocations. 1190 int non_escaped_length = non_escaped_worklist.length(); 1191 for (int next = 0; next < non_escaped_length; next++) { 1192 JavaObjectNode* ptn = non_escaped_worklist.at(next); 1193 PointsToNode::EscapeState es = ptn->escape_state(); 1194 assert(es <= PointsToNode::ArgEscape, "sanity"); 1195 if (es == PointsToNode::NoEscape) { 1196 if (find_init_values(ptn, null_obj, _igvn) > 0) { 1197 // Adding references to NULL object does not change escape states 1198 // since it does not escape. Also no fields are added to NULL object. 1199 add_java_object_edges(null_obj, false); 1200 } 1201 } 1202 Node* n = ptn->ideal_node(); 1203 if (n->is_Allocate()) { 1204 // The object allocated by this Allocate node will never be 1205 // seen by an other thread. Mark it so that when it is 1206 // expanded no MemBarStoreStore is added. 1207 InitializeNode* ini = n->as_Allocate()->initialization(); 1208 if (ini != NULL) 1209 ini->set_does_not_escape(); 1210 } 1211 } 1212 return true; // Finished graph construction. 1213 } 1214 1215 // Propagate GlobalEscape and ArgEscape escape states to all nodes 1216 // and check that we still have non-escaping java objects. 1217 bool ConnectionGraph::find_non_escaped_objects(GrowableArray<PointsToNode*>& ptnodes_worklist, 1218 GrowableArray<JavaObjectNode*>& non_escaped_worklist) { 1219 GrowableArray<PointsToNode*> escape_worklist; 1220 // First, put all nodes with GlobalEscape and ArgEscape states on worklist. 1221 int ptnodes_length = ptnodes_worklist.length(); 1222 for (int next = 0; next < ptnodes_length; ++next) { 1223 PointsToNode* ptn = ptnodes_worklist.at(next); 1224 if (ptn->escape_state() >= PointsToNode::ArgEscape || 1225 ptn->fields_escape_state() >= PointsToNode::ArgEscape) { 1226 escape_worklist.push(ptn); 1227 } 1228 } 1229 // Set escape states to referenced nodes (edges list). 1230 while (escape_worklist.length() > 0) { 1231 PointsToNode* ptn = escape_worklist.pop(); 1232 PointsToNode::EscapeState es = ptn->escape_state(); 1233 PointsToNode::EscapeState field_es = ptn->fields_escape_state(); 1234 if (ptn->is_Field() && ptn->as_Field()->is_oop() && 1235 es >= PointsToNode::ArgEscape) { 1236 // GlobalEscape or ArgEscape state of field means it has unknown value. 1237 if (add_edge(ptn, phantom_obj)) { 1238 // New edge was added 1239 add_field_uses_to_worklist(ptn->as_Field()); 1240 } 1241 } 1242 for (EdgeIterator i(ptn); i.has_next(); i.next()) { 1243 PointsToNode* e = i.get(); 1244 if (e->is_Arraycopy()) { 1245 assert(ptn->arraycopy_dst(), "sanity"); 1246 // Propagate only fields escape state through arraycopy edge. 1247 if (e->fields_escape_state() < field_es) { 1248 set_fields_escape_state(e, field_es); 1249 escape_worklist.push(e); 1250 } 1251 } else if (es >= field_es) { 1252 // fields_escape_state is also set to 'es' if it is less than 'es'. 1253 if (e->escape_state() < es) { 1254 set_escape_state(e, es); 1255 escape_worklist.push(e); 1256 } 1257 } else { 1258 // Propagate field escape state. 1259 bool es_changed = false; 1260 if (e->fields_escape_state() < field_es) { 1261 set_fields_escape_state(e, field_es); 1262 es_changed = true; 1263 } 1264 if ((e->escape_state() < field_es) && 1265 e->is_Field() && ptn->is_JavaObject() && 1266 e->as_Field()->is_oop()) { 1267 // Change escape state of referenced fileds. 1268 set_escape_state(e, field_es); 1269 es_changed = true;; 1270 } else if (e->escape_state() < es) { 1271 set_escape_state(e, es); 1272 es_changed = true;; 1273 } 1274 if (es_changed) { 1275 escape_worklist.push(e); 1276 } 1277 } 1278 } 1279 } 1280 // Remove escaped objects from non_escaped list. 1281 for (int next = non_escaped_worklist.length()-1; next >= 0 ; --next) { 1282 JavaObjectNode* ptn = non_escaped_worklist.at(next); 1283 if (ptn->escape_state() >= PointsToNode::GlobalEscape) { 1284 non_escaped_worklist.delete_at(next); 1285 } 1286 if (ptn->escape_state() == PointsToNode::NoEscape) { 1287 // Find fields in non-escaped allocations which have unknown value. 1288 find_init_values(ptn, phantom_obj, NULL); 1289 } 1290 } 1291 return (non_escaped_worklist.length() > 0); 1292 } 1293 1294 // Add all references to JavaObject node by walking over all uses. 1295 int ConnectionGraph::add_java_object_edges(JavaObjectNode* jobj, bool populate_worklist) { 1296 int new_edges = 0; 1297 if (populate_worklist) { 1298 // Populate _worklist by uses of jobj's uses. 1299 for (UseIterator i(jobj); i.has_next(); i.next()) { 1300 PointsToNode* use = i.get(); 1301 if (use->is_Arraycopy()) 1302 continue; 1303 add_uses_to_worklist(use); 1304 if (use->is_Field() && use->as_Field()->is_oop()) { 1305 // Put on worklist all field's uses (loads) and 1306 // related field nodes (same base and offset). 1307 add_field_uses_to_worklist(use->as_Field()); 1308 } 1309 } 1310 } 1311 for (int l = 0; l < _worklist.length(); l++) { 1312 PointsToNode* use = _worklist.at(l); 1313 if (PointsToNode::is_base_use(use)) { 1314 // Add reference from jobj to field and from field to jobj (field's base). 1315 use = PointsToNode::get_use_node(use)->as_Field(); 1316 if (add_base(use->as_Field(), jobj)) { 1317 new_edges++; 1318 } 1319 continue; 1320 } 1321 assert(!use->is_JavaObject(), "sanity"); 1322 if (use->is_Arraycopy()) { 1323 if (jobj == null_obj) // NULL object does not have field edges 1324 continue; 1325 // Added edge from Arraycopy node to arraycopy's source java object 1326 if (add_edge(use, jobj)) { 1327 jobj->set_arraycopy_src(); 1328 new_edges++; 1329 } 1330 // and stop here. 1331 continue; 1332 } 1333 if (!add_edge(use, jobj)) 1334 continue; // No new edge added, there was such edge already. 1335 new_edges++; 1336 if (use->is_LocalVar()) { 1337 add_uses_to_worklist(use); 1338 if (use->arraycopy_dst()) { 1339 for (EdgeIterator i(use); i.has_next(); i.next()) { 1340 PointsToNode* e = i.get(); 1341 if (e->is_Arraycopy()) { 1342 if (jobj == null_obj) // NULL object does not have field edges 1343 continue; 1344 // Add edge from arraycopy's destination java object to Arraycopy node. 1345 if (add_edge(jobj, e)) { 1346 new_edges++; 1347 jobj->set_arraycopy_dst(); 1348 } 1349 } 1350 } 1351 } 1352 } else { 1353 // Added new edge to stored in field values. 1354 // Put on worklist all field's uses (loads) and 1355 // related field nodes (same base and offset). 1356 add_field_uses_to_worklist(use->as_Field()); 1357 } 1358 } 1359 _worklist.clear(); 1360 _in_worklist.Reset(); 1361 return new_edges; 1362 } 1363 1364 // Put on worklist all related field nodes. 1365 void ConnectionGraph::add_field_uses_to_worklist(FieldNode* field) { 1366 assert(field->is_oop(), "sanity"); 1367 int offset = field->offset(); 1368 add_uses_to_worklist(field); 1369 // Loop over all bases of this field and push on worklist Field nodes 1370 // with the same offset and base (since they may reference the same field). 1371 for (BaseIterator i(field); i.has_next(); i.next()) { 1372 PointsToNode* base = i.get(); 1373 add_fields_to_worklist(field, base); 1374 // Check if the base was source object of arraycopy and go over arraycopy's 1375 // destination objects since values stored to a field of source object are 1376 // accessable by uses (loads) of fields of destination objects. 1377 if (base->arraycopy_src()) { 1378 for (UseIterator j(base); j.has_next(); j.next()) { 1379 PointsToNode* arycp = j.get(); 1380 if (arycp->is_Arraycopy()) { 1381 for (UseIterator k(arycp); k.has_next(); k.next()) { 1382 PointsToNode* abase = k.get(); 1383 if (abase->arraycopy_dst() && abase != base) { 1384 // Look for the same arracopy reference. 1385 add_fields_to_worklist(field, abase); 1386 } 1387 } 1388 } 1389 } 1390 } 1391 } 1392 } 1393 1394 // Put on worklist all related field nodes. 1395 void ConnectionGraph::add_fields_to_worklist(FieldNode* field, PointsToNode* base) { 1396 int offset = field->offset(); 1397 if (base->is_LocalVar()) { 1398 for (UseIterator j(base); j.has_next(); j.next()) { 1399 PointsToNode* f = j.get(); 1400 if (PointsToNode::is_base_use(f)) { // Field 1401 f = PointsToNode::get_use_node(f); 1402 if (f == field || !f->as_Field()->is_oop()) 1403 continue; 1404 int offs = f->as_Field()->offset(); 1405 if (offs == offset || offset == Type::OffsetBot || offs == Type::OffsetBot) { 1406 add_to_worklist(f); 1407 } 1408 } 1409 } 1410 } else { 1411 assert(base->is_JavaObject(), "sanity"); 1412 if (// Skip phantom_object since it is only used to indicate that 1413 // this field's content globally escapes. 1414 (base != phantom_obj) && 1415 // NULL object node does not have fields. 1416 (base != null_obj)) { 1417 for (EdgeIterator i(base); i.has_next(); i.next()) { 1418 PointsToNode* f = i.get(); 1419 // Skip arraycopy edge since store to destination object field 1420 // does not update value in source object field. 1421 if (f->is_Arraycopy()) { 1422 assert(base->arraycopy_dst(), "sanity"); 1423 continue; 1424 } 1425 if (f == field || !f->as_Field()->is_oop()) 1426 continue; 1427 int offs = f->as_Field()->offset(); 1428 if (offs == offset || offset == Type::OffsetBot || offs == Type::OffsetBot) { 1429 add_to_worklist(f); 1430 } 1431 } 1432 } 1433 } 1434 } 1435 1436 // Find fields which have unknown value. 1437 int ConnectionGraph::find_field_value(FieldNode* field) { 1438 // Escaped fields should have init value already. 1439 assert(field->escape_state() == PointsToNode::NoEscape, "sanity"); 1440 int new_edges = 0; 1441 for (BaseIterator i(field); i.has_next(); i.next()) { 1442 PointsToNode* base = i.get(); 1443 if (base->is_JavaObject()) { 1444 // Skip Allocate's fields which will be processed later. 1445 if (base->ideal_node()->is_Allocate()) 1446 return 0; 1447 assert(base == null_obj, "only NULL ptr base expected here"); 1448 } 1449 } 1450 if (add_edge(field, phantom_obj)) { 1451 // New edge was added 1452 new_edges++; 1453 add_field_uses_to_worklist(field); 1454 } 1455 return new_edges; 1456 } 1457 1458 // Find fields initializing values for allocations. 1459 int ConnectionGraph::find_init_values(JavaObjectNode* pta, PointsToNode* init_val, PhaseTransform* phase) { 1460 assert(pta->escape_state() == PointsToNode::NoEscape, "Not escaped Allocate nodes only"); 1461 int new_edges = 0; 1462 Node* alloc = pta->ideal_node(); 1463 if (init_val == phantom_obj) { 1464 // Do nothing for Allocate nodes since its fields values are "known". 1465 if (alloc->is_Allocate()) 1466 return 0; 1467 assert(alloc->as_CallStaticJava(), "sanity"); 1468 #ifdef ASSERT 1469 if (alloc->as_CallStaticJava()->method() == NULL) { 1470 const char* name = alloc->as_CallStaticJava()->_name; 1471 assert(strncmp(name, "_multianewarray", 15) == 0, "sanity"); 1472 } 1473 #endif 1474 // Non-escaped allocation returned from Java or runtime call have 1475 // unknown values in fields. 1476 for (EdgeIterator i(pta); i.has_next(); i.next()) { 1477 PointsToNode* field = i.get(); 1478 if (field->is_Field() && field->as_Field()->is_oop()) { 1479 if (add_edge(field, phantom_obj)) { 1480 // New edge was added 1481 new_edges++; 1482 add_field_uses_to_worklist(field->as_Field()); 1483 } 1484 } 1485 } 1486 return new_edges; 1487 } 1488 assert(init_val == null_obj, "sanity"); 1489 // Do nothing for Call nodes since its fields values are unknown. 1490 if (!alloc->is_Allocate()) 1491 return 0; 1492 1493 InitializeNode* ini = alloc->as_Allocate()->initialization(); 1494 bool visited_bottom_offset = false; 1495 GrowableArray<int> offsets_worklist; 1496 1497 // Check if an oop field's initializing value is recorded and add 1498 // a corresponding NULL if field's value if it is not recorded. 1499 // Connection Graph does not record a default initialization by NULL 1500 // captured by Initialize node. 1501 // 1502 for (EdgeIterator i(pta); i.has_next(); i.next()) { 1503 PointsToNode* field = i.get(); // Field (AddP) 1504 if (!field->is_Field() || !field->as_Field()->is_oop()) 1505 continue; // Not oop field 1506 int offset = field->as_Field()->offset(); 1507 if (offset == Type::OffsetBot) { 1508 if (!visited_bottom_offset) { 1509 // OffsetBot is used to reference array's element, 1510 // always add reference to NULL to all Field nodes since we don't 1511 // known which element is referenced. 1512 if (add_edge(field, null_obj)) { 1513 // New edge was added 1514 new_edges++; 1515 add_field_uses_to_worklist(field->as_Field()); 1516 visited_bottom_offset = true; 1517 } 1518 } 1519 } else { 1520 // Check only oop fields. 1521 const Type* adr_type = field->ideal_node()->as_AddP()->bottom_type(); 1522 if (adr_type->isa_rawptr()) { 1523 #ifdef ASSERT 1524 // Raw pointers are used for initializing stores so skip it 1525 // since it should be recorded already 1526 Node* base = get_addp_base(field->ideal_node()); 1527 assert(adr_type->isa_rawptr() && base->is_Proj() && 1528 (base->in(0) == alloc),"unexpected pointer type"); 1529 #endif 1530 continue; 1531 } 1532 if (!offsets_worklist.contains(offset)) { 1533 offsets_worklist.append(offset); 1534 Node* value = NULL; 1535 if (ini != NULL) { 1536 // StoreP::memory_type() == T_ADDRESS 1537 BasicType ft = UseCompressedOops ? T_NARROWOOP : T_ADDRESS; 1538 Node* store = ini->find_captured_store(offset, type2aelembytes(ft, true), phase); 1539 // Make sure initializing store has the same type as this AddP. 1540 // This AddP may reference non existing field because it is on a 1541 // dead branch of bimorphic call which is not eliminated yet. 1542 if (store != NULL && store->is_Store() && 1543 store->as_Store()->memory_type() == ft) { 1544 value = store->in(MemNode::ValueIn); 1545 #ifdef ASSERT 1546 if (VerifyConnectionGraph) { 1547 // Verify that AddP already points to all objects the value points to. 1548 PointsToNode* val = ptnode_adr(value->_idx); 1549 assert((val != NULL), "should be processed already"); 1550 PointsToNode* missed_obj = NULL; 1551 if (val->is_JavaObject()) { 1552 if (!field->points_to(val->as_JavaObject())) { 1553 missed_obj = val; 1554 } 1555 } else { 1556 if (!val->is_LocalVar() || (val->edge_count() == 0)) { 1557 tty->print_cr("----------init store has invalid value -----"); 1558 store->dump(); 1559 val->dump(); 1560 assert(val->is_LocalVar() && (val->edge_count() > 0), "should be processed already"); 1561 } 1562 for (EdgeIterator j(val); j.has_next(); j.next()) { 1563 PointsToNode* obj = j.get(); 1564 if (obj->is_JavaObject()) { 1565 if (!field->points_to(obj->as_JavaObject())) { 1566 missed_obj = obj; 1567 break; 1568 } 1569 } 1570 } 1571 } 1572 if (missed_obj != NULL) { 1573 tty->print_cr("----------field---------------------------------"); 1574 field->dump(); 1575 tty->print_cr("----------missed referernce to object-----------"); 1576 missed_obj->dump(); 1577 tty->print_cr("----------object referernced by init store -----"); 1578 store->dump(); 1579 val->dump(); 1580 assert(!field->points_to(missed_obj->as_JavaObject()), "missed JavaObject reference"); 1581 } 1582 } 1583 #endif 1584 } else { 1585 // There could be initializing stores which follow allocation. 1586 // For example, a volatile field store is not collected 1587 // by Initialize node. 1588 // 1589 // Need to check for dependent loads to separate such stores from 1590 // stores which follow loads. For now, add initial value NULL so 1591 // that compare pointers optimization works correctly. 1592 } 1593 } 1594 if (value == NULL) { 1595 // A field's initializing value was not recorded. Add NULL. 1596 if (add_edge(field, null_obj)) { 1597 // New edge was added 1598 new_edges++; 1599 add_field_uses_to_worklist(field->as_Field()); 1600 } 1601 } 1602 } 1603 } 1604 } 1605 return new_edges; 1606 } 1607 1608 // Adjust scalar_replaceable state after Connection Graph is built. 1609 void ConnectionGraph::adjust_scalar_replaceable_state(JavaObjectNode* jobj) { 1610 // Search for non-escaping objects which are not scalar replaceable 1611 // and mark them to propagate the state to referenced objects. 1612 1613 // 1. An object is not scalar replaceable if the field into which it is 1614 // stored has unknown offset (stored into unknown element of an array). 1615 // 1616 for (UseIterator i(jobj); i.has_next(); i.next()) { 1617 PointsToNode* use = i.get(); 1618 assert(!use->is_Arraycopy(), "sanity"); 1619 if (use->is_Field()) { 1620 FieldNode* field = use->as_Field(); 1621 assert(field->is_oop() && field->scalar_replaceable() && 1622 field->fields_escape_state() == PointsToNode::NoEscape, "sanity"); 1623 if (field->offset() == Type::OffsetBot) { 1624 jobj->set_scalar_replaceable(false); 1625 return; 1626 } 1627 // 2. An object is not scalar replaceable if the field into which it is 1628 // stored has multiple bases one of which is null. 1629 if (field->base_count() > 1) { 1630 for (BaseIterator i(field); i.has_next(); i.next()) { 1631 PointsToNode* base = i.get(); 1632 if (base == null_obj) { 1633 jobj->set_scalar_replaceable(false); 1634 return; 1635 } 1636 } 1637 } 1638 } 1639 assert(use->is_Field() || use->is_LocalVar(), "sanity"); 1640 // 3. An object is not scalar replaceable if it is merged with other objects. 1641 for (EdgeIterator j(use); j.has_next(); j.next()) { 1642 PointsToNode* ptn = j.get(); 1643 if (ptn->is_JavaObject() && ptn != jobj) { 1644 // Mark all objects. 1645 jobj->set_scalar_replaceable(false); 1646 ptn->set_scalar_replaceable(false); 1647 } 1648 } 1649 if (!jobj->scalar_replaceable()) { 1650 return; 1651 } 1652 } 1653 1654 for (EdgeIterator j(jobj); j.has_next(); j.next()) { 1655 // Non-escaping object node should point only to field nodes. 1656 FieldNode* field = j.get()->as_Field(); 1657 int offset = field->as_Field()->offset(); 1658 1659 // 4. An object is not scalar replaceable if it has a field with unknown 1660 // offset (array's element is accessed in loop). 1661 if (offset == Type::OffsetBot) { 1662 jobj->set_scalar_replaceable(false); 1663 return; 1664 } 1665 // 5. Currently an object is not scalar replaceable if a LoadStore node 1666 // access its field since the field value is unknown after it. 1667 // 1668 Node* n = field->ideal_node(); 1669 for (DUIterator_Fast imax, i = n->fast_outs(imax); i < imax; i++) { 1670 if (n->fast_out(i)->is_LoadStore()) { 1671 jobj->set_scalar_replaceable(false); 1672 return; 1673 } 1674 } 1675 1676 // 6. Or the address may point to more then one object. This may produce 1677 // the false positive result (set not scalar replaceable) 1678 // since the flow-insensitive escape analysis can't separate 1679 // the case when stores overwrite the field's value from the case 1680 // when stores happened on different control branches. 1681 // 1682 // Note: it will disable scalar replacement in some cases: 1683 // 1684 // Point p[] = new Point[1]; 1685 // p[0] = new Point(); // Will be not scalar replaced 1686 // 1687 // but it will save us from incorrect optimizations in next cases: 1688 // 1689 // Point p[] = new Point[1]; 1690 // if ( x ) p[0] = new Point(); // Will be not scalar replaced 1691 // 1692 if (field->base_count() > 1) { 1693 for (BaseIterator i(field); i.has_next(); i.next()) { 1694 PointsToNode* base = i.get(); 1695 // Don't take into account LocalVar nodes which 1696 // may point to only one object which should be also 1697 // this field's base by now. 1698 if (base->is_JavaObject() && base != jobj) { 1699 // Mark all bases. 1700 jobj->set_scalar_replaceable(false); 1701 base->set_scalar_replaceable(false); 1702 } 1703 } 1704 } 1705 } 1706 } 1707 1708 #ifdef ASSERT 1709 void ConnectionGraph::verify_connection_graph( 1710 GrowableArray<PointsToNode*>& ptnodes_worklist, 1711 GrowableArray<JavaObjectNode*>& non_escaped_worklist, 1712 GrowableArray<JavaObjectNode*>& java_objects_worklist, 1713 GrowableArray<Node*>& addp_worklist) { 1714 // Verify that graph is complete - no new edges could be added. 1715 int java_objects_length = java_objects_worklist.length(); 1716 int non_escaped_length = non_escaped_worklist.length(); 1717 int new_edges = 0; 1718 for (int next = 0; next < java_objects_length; ++next) { 1719 JavaObjectNode* ptn = java_objects_worklist.at(next); 1720 new_edges += add_java_object_edges(ptn, true); 1721 } 1722 assert(new_edges == 0, "graph was not complete"); 1723 // Verify that escape state is final. 1724 int length = non_escaped_worklist.length(); 1725 find_non_escaped_objects(ptnodes_worklist, non_escaped_worklist); 1726 assert((non_escaped_length == non_escaped_worklist.length()) && 1727 (non_escaped_length == length) && 1728 (_worklist.length() == 0), "escape state was not final"); 1729 1730 // Verify fields information. 1731 int addp_length = addp_worklist.length(); 1732 for (int next = 0; next < addp_length; ++next ) { 1733 Node* n = addp_worklist.at(next); 1734 FieldNode* field = ptnode_adr(n->_idx)->as_Field(); 1735 if (field->is_oop()) { 1736 // Verify that field has all bases 1737 Node* base = get_addp_base(n); 1738 PointsToNode* ptn = ptnode_adr(base->_idx); 1739 if (ptn->is_JavaObject()) { 1740 assert(field->has_base(ptn->as_JavaObject()), "sanity"); 1741 } else { 1742 assert(ptn->is_LocalVar(), "sanity"); 1743 for (EdgeIterator i(ptn); i.has_next(); i.next()) { 1744 PointsToNode* e = i.get(); 1745 if (e->is_JavaObject()) { 1746 assert(field->has_base(e->as_JavaObject()), "sanity"); 1747 } 1748 } 1749 } 1750 // Verify that all fields have initializing values. 1751 if (field->edge_count() == 0) { 1752 tty->print_cr("----------field does not have references----------"); 1753 field->dump(); 1754 for (BaseIterator i(field); i.has_next(); i.next()) { 1755 PointsToNode* base = i.get(); 1756 tty->print_cr("----------field has next base---------------------"); 1757 base->dump(); 1758 if (base->is_JavaObject() && (base != phantom_obj) && (base != null_obj)) { 1759 tty->print_cr("----------base has fields-------------------------"); 1760 for (EdgeIterator j(base); j.has_next(); j.next()) { 1761 j.get()->dump(); 1762 } 1763 tty->print_cr("----------base has references---------------------"); 1764 for (UseIterator j(base); j.has_next(); j.next()) { 1765 j.get()->dump(); 1766 } 1767 } 1768 } 1769 for (UseIterator i(field); i.has_next(); i.next()) { 1770 i.get()->dump(); 1771 } 1772 assert(field->edge_count() > 0, "sanity"); 1773 } 1774 } 1775 } 1776 } 1777 #endif 1778 1779 // Optimize ideal graph. 1780 void ConnectionGraph::optimize_ideal_graph(GrowableArray<Node*>& ptr_cmp_worklist, 1781 GrowableArray<Node*>& storestore_worklist) { 1782 Compile* C = _compile; 1783 PhaseIterGVN* igvn = _igvn; 1784 if (EliminateLocks) { 1785 // Mark locks before changing ideal graph. 1786 int cnt = C->macro_count(); 1787 for( int i=0; i < cnt; i++ ) { 1788 Node *n = C->macro_node(i); 1789 if (n->is_AbstractLock()) { // Lock and Unlock nodes 1790 AbstractLockNode* alock = n->as_AbstractLock(); 1791 if (!alock->is_non_esc_obj()) { 1792 if (not_global_escape(alock->obj_node())) { 1793 assert(!alock->is_eliminated() || alock->is_coarsened(), "sanity"); 1794 // The lock could be marked eliminated by lock coarsening 1795 // code during first IGVN before EA. Replace coarsened flag 1796 // to eliminate all associated locks/unlocks. 1797 alock->set_non_esc_obj(); 1798 } 1799 } 1800 } 1801 } 1802 } 1803 1804 if (OptimizePtrCompare) { 1805 // Add ConI(#CC_GT) and ConI(#CC_EQ). 1806 _pcmp_neq = igvn->makecon(TypeInt::CC_GT); 1807 _pcmp_eq = igvn->makecon(TypeInt::CC_EQ); 1808 // Optimize objects compare. 1809 while (ptr_cmp_worklist.length() != 0) { 1810 Node *n = ptr_cmp_worklist.pop(); 1811 Node *res = optimize_ptr_compare(n); 1812 if (res != NULL) { 1813 #ifndef PRODUCT 1814 if (PrintOptimizePtrCompare) { 1815 tty->print_cr("++++ Replaced: %d %s(%d,%d) --> %s", n->_idx, (n->Opcode() == Op_CmpP ? "CmpP" : "CmpN"), n->in(1)->_idx, n->in(2)->_idx, (res == _pcmp_eq ? "EQ" : "NotEQ")); 1816 if (Verbose) { 1817 n->dump(1); 1818 } 1819 } 1820 #endif 1821 igvn->replace_node(n, res); 1822 } 1823 } 1824 // cleanup 1825 if (_pcmp_neq->outcnt() == 0) 1826 igvn->hash_delete(_pcmp_neq); 1827 if (_pcmp_eq->outcnt() == 0) 1828 igvn->hash_delete(_pcmp_eq); 1829 } 1830 1831 // For MemBarStoreStore nodes added in library_call.cpp, check 1832 // escape status of associated AllocateNode and optimize out 1833 // MemBarStoreStore node if the allocated object never escapes. 1834 while (storestore_worklist.length() != 0) { 1835 Node *n = storestore_worklist.pop(); 1836 MemBarStoreStoreNode *storestore = n ->as_MemBarStoreStore(); 1837 Node *alloc = storestore->in(MemBarNode::Precedent)->in(0); 1838 assert (alloc->is_Allocate(), "storestore should point to AllocateNode"); 1839 if (not_global_escape(alloc)) { 1840 MemBarNode* mb = MemBarNode::make(C, Op_MemBarCPUOrder, Compile::AliasIdxBot); 1841 mb->init_req(TypeFunc::Memory, storestore->in(TypeFunc::Memory)); 1842 mb->init_req(TypeFunc::Control, storestore->in(TypeFunc::Control)); 1843 igvn->register_new_node_with_optimizer(mb); 1844 igvn->replace_node(storestore, mb); 1845 } 1846 } 1847 } 1848 1849 // Optimize objects compare. 1850 Node* ConnectionGraph::optimize_ptr_compare(Node* n) { 1851 assert(OptimizePtrCompare, "sanity"); 1852 PointsToNode* ptn1 = ptnode_adr(n->in(1)->_idx); 1853 PointsToNode* ptn2 = ptnode_adr(n->in(2)->_idx); 1854 JavaObjectNode* jobj1 = unique_java_object(n->in(1)); 1855 JavaObjectNode* jobj2 = unique_java_object(n->in(2)); 1856 assert(ptn1->is_JavaObject() || ptn1->is_LocalVar(), "sanity"); 1857 assert(ptn2->is_JavaObject() || ptn2->is_LocalVar(), "sanity"); 1858 1859 // Check simple cases first. 1860 if (jobj1 != NULL) { 1861 if (jobj1->escape_state() == PointsToNode::NoEscape) { 1862 if (jobj1 == jobj2) { 1863 // Comparing the same not escaping object. 1864 return _pcmp_eq; 1865 } 1866 Node* obj = jobj1->ideal_node(); 1867 // Comparing not escaping allocation. 1868 if ((obj->is_Allocate() || obj->is_CallStaticJava()) && 1869 !ptn2->points_to(jobj1)) { 1870 return _pcmp_neq; // This includes nullness check. 1871 } 1872 } 1873 } 1874 if (jobj2 != NULL) { 1875 if (jobj2->escape_state() == PointsToNode::NoEscape) { 1876 Node* obj = jobj2->ideal_node(); 1877 // Comparing not escaping allocation. 1878 if ((obj->is_Allocate() || obj->is_CallStaticJava()) && 1879 !ptn1->points_to(jobj2)) { 1880 return _pcmp_neq; // This includes nullness check. 1881 } 1882 } 1883 } 1884 if (jobj1 != NULL && jobj1 != phantom_obj && 1885 jobj2 != NULL && jobj2 != phantom_obj && 1886 jobj1->ideal_node()->is_Con() && 1887 jobj2->ideal_node()->is_Con()) { 1888 // Klass or String constants compare. Need to be careful with 1889 // compressed pointers - compare types of ConN and ConP instead of nodes. 1890 const Type* t1 = jobj1->ideal_node()->get_ptr_type(); 1891 const Type* t2 = jobj2->ideal_node()->get_ptr_type(); 1892 if (t1->make_ptr() == t2->make_ptr()) { 1893 return _pcmp_eq; 1894 } else { 1895 return _pcmp_neq; 1896 } 1897 } 1898 if (ptn1->meet(ptn2)) { 1899 return NULL; // Sets are not disjoint 1900 } 1901 1902 // Sets are disjoint. 1903 bool set1_has_unknown_ptr = ptn1->points_to(phantom_obj); 1904 bool set2_has_unknown_ptr = ptn2->points_to(phantom_obj); 1905 bool set1_has_null_ptr = ptn1->points_to(null_obj); 1906 bool set2_has_null_ptr = ptn2->points_to(null_obj); 1907 if (set1_has_unknown_ptr && set2_has_null_ptr || 1908 set2_has_unknown_ptr && set1_has_null_ptr) { 1909 // Check nullness of unknown object. 1910 return NULL; 1911 } 1912 1913 // Disjointness by itself is not sufficient since 1914 // alias analysis is not complete for escaped objects. 1915 // Disjoint sets are definitely unrelated only when 1916 // at least one set has only not escaping allocations. 1917 if (!set1_has_unknown_ptr && !set1_has_null_ptr) { 1918 if (ptn1->non_escaping_allocation()) { 1919 return _pcmp_neq; 1920 } 1921 } 1922 if (!set2_has_unknown_ptr && !set2_has_null_ptr) { 1923 if (ptn2->non_escaping_allocation()) { 1924 return _pcmp_neq; 1925 } 1926 } 1927 return NULL; 1928 } 1929 1930 // Connection Graph constuction functions. 1931 1932 void ConnectionGraph::add_local_var(Node *n, PointsToNode::EscapeState es) { 1933 PointsToNode* ptadr = _nodes.at(n->_idx); 1934 if (ptadr != NULL) { 1935 assert(ptadr->is_LocalVar() && ptadr->ideal_node() == n, "sanity"); 1936 return; 1937 } 1938 Compile* C = _compile; 1939 ptadr = new (C->comp_arena()) LocalVarNode(this, n, es); 1940 _nodes.at_put(n->_idx, ptadr); 1941 } 1942 1943 void ConnectionGraph::add_java_object(Node *n, PointsToNode::EscapeState es) { 1944 PointsToNode* ptadr = _nodes.at(n->_idx); 1945 if (ptadr != NULL) { 1946 assert(ptadr->is_JavaObject() && ptadr->ideal_node() == n, "sanity"); 1947 return; 1948 } 1949 Compile* C = _compile; 1950 ptadr = new (C->comp_arena()) JavaObjectNode(this, n, es); 1951 _nodes.at_put(n->_idx, ptadr); 1952 } 1953 1954 void ConnectionGraph::add_field(Node *n, PointsToNode::EscapeState es, int offset) { 1955 PointsToNode* ptadr = _nodes.at(n->_idx); 1956 if (ptadr != NULL) { 1957 assert(ptadr->is_Field() && ptadr->ideal_node() == n, "sanity"); 1958 return; 1959 } 1960 bool unsafe = false; 1961 bool is_oop = is_oop_field(n, offset, &unsafe); 1962 if (unsafe) { 1963 es = PointsToNode::GlobalEscape; 1964 } 1965 Compile* C = _compile; 1966 FieldNode* field = new (C->comp_arena()) FieldNode(this, n, es, offset, is_oop); 1967 _nodes.at_put(n->_idx, field); 1968 } 1969 1970 void ConnectionGraph::add_arraycopy(Node *n, PointsToNode::EscapeState es, 1971 PointsToNode* src, PointsToNode* dst) { 1972 assert(!src->is_Field() && !dst->is_Field(), "only for JavaObject and LocalVar"); 1973 assert((src != null_obj) && (dst != null_obj), "not for ConP NULL"); 1974 PointsToNode* ptadr = _nodes.at(n->_idx); 1975 if (ptadr != NULL) { 1976 assert(ptadr->is_Arraycopy() && ptadr->ideal_node() == n, "sanity"); 1977 return; 1978 } 1979 Compile* C = _compile; 1980 ptadr = new (C->comp_arena()) ArraycopyNode(this, n, es); 1981 _nodes.at_put(n->_idx, ptadr); 1982 // Add edge from arraycopy node to source object. 1983 (void)add_edge(ptadr, src); 1984 src->set_arraycopy_src(); 1985 // Add edge from destination object to arraycopy node. 1986 (void)add_edge(dst, ptadr); 1987 dst->set_arraycopy_dst(); 1988 } 1989 1990 bool ConnectionGraph::is_oop_field(Node* n, int offset, bool* unsafe) { 1991 const Type* adr_type = n->as_AddP()->bottom_type(); 1992 BasicType bt = T_INT; 1993 if (offset == Type::OffsetBot) { 1994 // Check only oop fields. 1995 if (!adr_type->isa_aryptr() || 1996 (adr_type->isa_aryptr()->klass() == NULL) || 1997 adr_type->isa_aryptr()->klass()->is_obj_array_klass()) { 1998 // OffsetBot is used to reference array's element. Ignore first AddP. 1999 if (find_second_addp(n, n->in(AddPNode::Base)) == NULL) { 2000 bt = T_OBJECT; 2001 } 2002 } 2003 } else if (offset != oopDesc::klass_offset_in_bytes()) { 2004 if (adr_type->isa_instptr()) { 2005 ciField* field = _compile->alias_type(adr_type->isa_instptr())->field(); 2006 if (field != NULL) { 2007 bt = field->layout_type(); 2008 } else { 2009 // Check for unsafe oop field access 2010 for (DUIterator_Fast imax, i = n->fast_outs(imax); i < imax; i++) { 2011 int opcode = n->fast_out(i)->Opcode(); 2012 if (opcode == Op_StoreP || opcode == Op_LoadP || 2013 opcode == Op_StoreN || opcode == Op_LoadN) { 2014 bt = T_OBJECT; 2015 (*unsafe) = true; 2016 break; 2017 } 2018 } 2019 } 2020 } else if (adr_type->isa_aryptr()) { 2021 if (offset == arrayOopDesc::length_offset_in_bytes()) { 2022 // Ignore array length load. 2023 } else if (find_second_addp(n, n->in(AddPNode::Base)) != NULL) { 2024 // Ignore first AddP. 2025 } else { 2026 const Type* elemtype = adr_type->isa_aryptr()->elem(); 2027 bt = elemtype->array_element_basic_type(); 2028 } 2029 } else if (adr_type->isa_rawptr() || adr_type->isa_klassptr()) { 2030 // Allocation initialization, ThreadLocal field access, unsafe access 2031 for (DUIterator_Fast imax, i = n->fast_outs(imax); i < imax; i++) { 2032 int opcode = n->fast_out(i)->Opcode(); 2033 if (opcode == Op_StoreP || opcode == Op_LoadP || 2034 opcode == Op_StoreN || opcode == Op_LoadN) { 2035 bt = T_OBJECT; 2036 break; 2037 } 2038 } 2039 } 2040 } 2041 return (bt == T_OBJECT || bt == T_NARROWOOP || bt == T_ARRAY); 2042 } 2043 2044 // Returns unique pointed java object or NULL. 2045 JavaObjectNode* ConnectionGraph::unique_java_object(Node *n) { 2046 assert(!_collecting, "should not call when contructed graph"); 2047 // If the node was created after the escape computation we can't answer. 2048 uint idx = n->_idx; 2049 if (idx >= nodes_size()) { 2050 return NULL; 2051 } 2052 PointsToNode* ptn = ptnode_adr(idx); 2053 if (ptn->is_JavaObject()) { 2054 return ptn->as_JavaObject(); 2055 } 2056 assert(ptn->is_LocalVar(), "sanity"); 2057 // Check all java objects it points to. 2058 JavaObjectNode* jobj = NULL; 2059 for (EdgeIterator i(ptn); i.has_next(); i.next()) { 2060 PointsToNode* e = i.get(); 2061 if (e->is_JavaObject()) { 2062 if (jobj == NULL) { 2063 jobj = e->as_JavaObject(); 2064 } else if (jobj != e) { 2065 return NULL; 2066 } 2067 } 2068 } 2069 return jobj; 2070 } 2071 2072 // Return true if this node points only to non-escaping allocations. 2073 bool PointsToNode::non_escaping_allocation() { 2074 if (is_JavaObject()) { 2075 Node* n = ideal_node(); 2076 if (n->is_Allocate() || n->is_CallStaticJava()) { 2077 return (escape_state() == PointsToNode::NoEscape); 2078 } else { 2079 return false; 2080 } 2081 } 2082 assert(is_LocalVar(), "sanity"); 2083 // Check all java objects it points to. 2084 for (EdgeIterator i(this); i.has_next(); i.next()) { 2085 PointsToNode* e = i.get(); 2086 if (e->is_JavaObject()) { 2087 Node* n = e->ideal_node(); 2088 if ((e->escape_state() != PointsToNode::NoEscape) || 2089 !(n->is_Allocate() || n->is_CallStaticJava())) { 2090 return false; 2091 } 2092 } 2093 } 2094 return true; 2095 } 2096 2097 // Return true if we know the node does not escape globally. 2098 bool ConnectionGraph::not_global_escape(Node *n) { 2099 assert(!_collecting, "should not call during graph construction"); 2100 // If the node was created after the escape computation we can't answer. 2101 uint idx = n->_idx; 2102 if (idx >= nodes_size()) { 2103 return false; 2104 } 2105 PointsToNode* ptn = ptnode_adr(idx); 2106 PointsToNode::EscapeState es = ptn->escape_state(); 2107 // If we have already computed a value, return it. 2108 if (es >= PointsToNode::GlobalEscape) 2109 return false; 2110 if (ptn->is_JavaObject()) { 2111 return true; // (es < PointsToNode::GlobalEscape); 2112 } 2113 assert(ptn->is_LocalVar(), "sanity"); 2114 // Check all java objects it points to. 2115 for (EdgeIterator i(ptn); i.has_next(); i.next()) { 2116 if (i.get()->escape_state() >= PointsToNode::GlobalEscape) 2117 return false; 2118 } 2119 return true; 2120 } 2121 2122 2123 // Helper functions 2124 2125 // Return true if this node points to specified node or nodes it points to. 2126 bool PointsToNode::points_to(JavaObjectNode* ptn) const { 2127 if (is_JavaObject()) { 2128 return (this == ptn); 2129 } 2130 assert(is_LocalVar() || is_Field(), "sanity"); 2131 for (EdgeIterator i(this); i.has_next(); i.next()) { 2132 if (i.get() == ptn) 2133 return true; 2134 } 2135 return false; 2136 } 2137 2138 // Return true if one node points to an other. 2139 bool PointsToNode::meet(PointsToNode* ptn) { 2140 if (this == ptn) { 2141 return true; 2142 } else if (ptn->is_JavaObject()) { 2143 return this->points_to(ptn->as_JavaObject()); 2144 } else if (this->is_JavaObject()) { 2145 return ptn->points_to(this->as_JavaObject()); 2146 } 2147 assert(this->is_LocalVar() && ptn->is_LocalVar(), "sanity"); 2148 int ptn_count = ptn->edge_count(); 2149 for (EdgeIterator i(this); i.has_next(); i.next()) { 2150 PointsToNode* this_e = i.get(); 2151 for (int j = 0; j < ptn_count; j++) { 2152 if (this_e == ptn->edge(j)) 2153 return true; 2154 } 2155 } 2156 return false; 2157 } 2158 2159 #ifdef ASSERT 2160 // Return true if bases point to this java object. 2161 bool FieldNode::has_base(JavaObjectNode* jobj) const { 2162 for (BaseIterator i(this); i.has_next(); i.next()) { 2163 if (i.get() == jobj) 2164 return true; 2165 } 2166 return false; 2167 } 2168 #endif 2169 2170 int ConnectionGraph::address_offset(Node* adr, PhaseTransform *phase) { 2171 const Type *adr_type = phase->type(adr); 2172 if (adr->is_AddP() && adr_type->isa_oopptr() == NULL && 2173 adr->in(AddPNode::Address)->is_Proj() && 2174 adr->in(AddPNode::Address)->in(0)->is_Allocate()) { 2175 // We are computing a raw address for a store captured by an Initialize 2176 // compute an appropriate address type. AddP cases #3 and #5 (see below). 2177 int offs = (int)phase->find_intptr_t_con(adr->in(AddPNode::Offset), Type::OffsetBot); 2178 assert(offs != Type::OffsetBot || 2179 adr->in(AddPNode::Address)->in(0)->is_AllocateArray(), 2180 "offset must be a constant or it is initialization of array"); 2181 return offs; 2182 } 2183 const TypePtr *t_ptr = adr_type->isa_ptr(); 2184 assert(t_ptr != NULL, "must be a pointer type"); 2185 return t_ptr->offset(); 2186 } 2187 2188 Node* ConnectionGraph::get_addp_base(Node *addp) { 2189 assert(addp->is_AddP(), "must be AddP"); 2190 // 2191 // AddP cases for Base and Address inputs: 2192 // case #1. Direct object's field reference: 2193 // Allocate 2194 // | 2195 // Proj #5 ( oop result ) 2196 // | 2197 // CheckCastPP (cast to instance type) 2198 // | | 2199 // AddP ( base == address ) 2200 // 2201 // case #2. Indirect object's field reference: 2202 // Phi 2203 // | 2204 // CastPP (cast to instance type) 2205 // | | 2206 // AddP ( base == address ) 2207 // 2208 // case #3. Raw object's field reference for Initialize node: 2209 // Allocate 2210 // | 2211 // Proj #5 ( oop result ) 2212 // top | 2213 // \ | 2214 // AddP ( base == top ) 2215 // 2216 // case #4. Array's element reference: 2217 // {CheckCastPP | CastPP} 2218 // | | | 2219 // | AddP ( array's element offset ) 2220 // | | 2221 // AddP ( array's offset ) 2222 // 2223 // case #5. Raw object's field reference for arraycopy stub call: 2224 // The inline_native_clone() case when the arraycopy stub is called 2225 // after the allocation before Initialize and CheckCastPP nodes. 2226 // Allocate 2227 // | 2228 // Proj #5 ( oop result ) 2229 // | | 2230 // AddP ( base == address ) 2231 // 2232 // case #6. Constant Pool, ThreadLocal, CastX2P or 2233 // Raw object's field reference: 2234 // {ConP, ThreadLocal, CastX2P, raw Load} 2235 // top | 2236 // \ | 2237 // AddP ( base == top ) 2238 // 2239 // case #7. Klass's field reference. 2240 // LoadKlass 2241 // | | 2242 // AddP ( base == address ) 2243 // 2244 // case #8. narrow Klass's field reference. 2245 // LoadNKlass 2246 // | 2247 // DecodeN 2248 // | | 2249 // AddP ( base == address ) 2250 // 2251 Node *base = addp->in(AddPNode::Base); 2252 if (base->uncast()->is_top()) { // The AddP case #3 and #6. 2253 base = addp->in(AddPNode::Address); 2254 while (base->is_AddP()) { 2255 // Case #6 (unsafe access) may have several chained AddP nodes. 2256 assert(base->in(AddPNode::Base)->uncast()->is_top(), "expected unsafe access address only"); 2257 base = base->in(AddPNode::Address); 2258 } 2259 Node* uncast_base = base->uncast(); 2260 int opcode = uncast_base->Opcode(); 2261 assert(opcode == Op_ConP || opcode == Op_ThreadLocal || 2262 opcode == Op_CastX2P || uncast_base->is_DecodeNarrowPtr() || 2263 (uncast_base->is_Mem() && (uncast_base->bottom_type()->isa_rawptr() != NULL)) || 2264 (uncast_base->is_Proj() && uncast_base->in(0)->is_Allocate()), "sanity"); 2265 } 2266 return base; 2267 } 2268 2269 Node* ConnectionGraph::find_second_addp(Node* addp, Node* n) { 2270 assert(addp->is_AddP() && addp->outcnt() > 0, "Don't process dead nodes"); 2271 Node* addp2 = addp->raw_out(0); 2272 if (addp->outcnt() == 1 && addp2->is_AddP() && 2273 addp2->in(AddPNode::Base) == n && 2274 addp2->in(AddPNode::Address) == addp) { 2275 assert(addp->in(AddPNode::Base) == n, "expecting the same base"); 2276 // 2277 // Find array's offset to push it on worklist first and 2278 // as result process an array's element offset first (pushed second) 2279 // to avoid CastPP for the array's offset. 2280 // Otherwise the inserted CastPP (LocalVar) will point to what 2281 // the AddP (Field) points to. Which would be wrong since 2282 // the algorithm expects the CastPP has the same point as 2283 // as AddP's base CheckCastPP (LocalVar). 2284 // 2285 // ArrayAllocation 2286 // | 2287 // CheckCastPP 2288 // | 2289 // memProj (from ArrayAllocation CheckCastPP) 2290 // | || 2291 // | || Int (element index) 2292 // | || | ConI (log(element size)) 2293 // | || | / 2294 // | || LShift 2295 // | || / 2296 // | AddP (array's element offset) 2297 // | | 2298 // | | ConI (array's offset: #12(32-bits) or #24(64-bits)) 2299 // | / / 2300 // AddP (array's offset) 2301 // | 2302 // Load/Store (memory operation on array's element) 2303 // 2304 return addp2; 2305 } 2306 return NULL; 2307 } 2308 2309 // 2310 // Adjust the type and inputs of an AddP which computes the 2311 // address of a field of an instance 2312 // 2313 bool ConnectionGraph::split_AddP(Node *addp, Node *base) { 2314 PhaseGVN* igvn = _igvn; 2315 const TypeOopPtr *base_t = igvn->type(base)->isa_oopptr(); 2316 assert(base_t != NULL && base_t->is_known_instance(), "expecting instance oopptr"); 2317 const TypeOopPtr *t = igvn->type(addp)->isa_oopptr(); 2318 if (t == NULL) { 2319 // We are computing a raw address for a store captured by an Initialize 2320 // compute an appropriate address type (cases #3 and #5). 2321 assert(igvn->type(addp) == TypeRawPtr::NOTNULL, "must be raw pointer"); 2322 assert(addp->in(AddPNode::Address)->is_Proj(), "base of raw address must be result projection from allocation"); 2323 intptr_t offs = (int)igvn->find_intptr_t_con(addp->in(AddPNode::Offset), Type::OffsetBot); 2324 assert(offs != Type::OffsetBot, "offset must be a constant"); 2325 t = base_t->add_offset(offs)->is_oopptr(); 2326 } 2327 int inst_id = base_t->instance_id(); 2328 assert(!t->is_known_instance() || t->instance_id() == inst_id, 2329 "old type must be non-instance or match new type"); 2330 2331 // The type 't' could be subclass of 'base_t'. 2332 // As result t->offset() could be large then base_t's size and it will 2333 // cause the failure in add_offset() with narrow oops since TypeOopPtr() 2334 // constructor verifies correctness of the offset. 2335 // 2336 // It could happened on subclass's branch (from the type profiling 2337 // inlining) which was not eliminated during parsing since the exactness 2338 // of the allocation type was not propagated to the subclass type check. 2339 // 2340 // Or the type 't' could be not related to 'base_t' at all. 2341 // It could happened when CHA type is different from MDO type on a dead path 2342 // (for example, from instanceof check) which is not collapsed during parsing. 2343 // 2344 // Do nothing for such AddP node and don't process its users since 2345 // this code branch will go away. 2346 // 2347 if (!t->is_known_instance() && 2348 !base_t->klass()->is_subtype_of(t->klass())) { 2349 return false; // bail out 2350 } 2351 const TypeOopPtr *tinst = base_t->add_offset(t->offset())->is_oopptr(); 2352 // Do NOT remove the next line: ensure a new alias index is allocated 2353 // for the instance type. Note: C++ will not remove it since the call 2354 // has side effect. 2355 int alias_idx = _compile->get_alias_index(tinst); 2356 igvn->set_type(addp, tinst); 2357 // record the allocation in the node map 2358 set_map(addp, get_map(base->_idx)); 2359 // Set addp's Base and Address to 'base'. 2360 Node *abase = addp->in(AddPNode::Base); 2361 Node *adr = addp->in(AddPNode::Address); 2362 if (adr->is_Proj() && adr->in(0)->is_Allocate() && 2363 adr->in(0)->_idx == (uint)inst_id) { 2364 // Skip AddP cases #3 and #5. 2365 } else { 2366 assert(!abase->is_top(), "sanity"); // AddP case #3 2367 if (abase != base) { 2368 igvn->hash_delete(addp); 2369 addp->set_req(AddPNode::Base, base); 2370 if (abase == adr) { 2371 addp->set_req(AddPNode::Address, base); 2372 } else { 2373 // AddP case #4 (adr is array's element offset AddP node) 2374 #ifdef ASSERT 2375 const TypeOopPtr *atype = igvn->type(adr)->isa_oopptr(); 2376 assert(adr->is_AddP() && atype != NULL && 2377 atype->instance_id() == inst_id, "array's element offset should be processed first"); 2378 #endif 2379 } 2380 igvn->hash_insert(addp); 2381 } 2382 } 2383 // Put on IGVN worklist since at least addp's type was changed above. 2384 record_for_optimizer(addp); 2385 return true; 2386 } 2387 2388 // 2389 // Create a new version of orig_phi if necessary. Returns either the newly 2390 // created phi or an existing phi. Sets create_new to indicate whether a new 2391 // phi was created. Cache the last newly created phi in the node map. 2392 // 2393 PhiNode *ConnectionGraph::create_split_phi(PhiNode *orig_phi, int alias_idx, GrowableArray<PhiNode *> &orig_phi_worklist, bool &new_created) { 2394 Compile *C = _compile; 2395 PhaseGVN* igvn = _igvn; 2396 new_created = false; 2397 int phi_alias_idx = C->get_alias_index(orig_phi->adr_type()); 2398 // nothing to do if orig_phi is bottom memory or matches alias_idx 2399 if (phi_alias_idx == alias_idx) { 2400 return orig_phi; 2401 } 2402 // Have we recently created a Phi for this alias index? 2403 PhiNode *result = get_map_phi(orig_phi->_idx); 2404 if (result != NULL && C->get_alias_index(result->adr_type()) == alias_idx) { 2405 return result; 2406 } 2407 // Previous check may fail when the same wide memory Phi was split into Phis 2408 // for different memory slices. Search all Phis for this region. 2409 if (result != NULL) { 2410 Node* region = orig_phi->in(0); 2411 for (DUIterator_Fast imax, i = region->fast_outs(imax); i < imax; i++) { 2412 Node* phi = region->fast_out(i); 2413 if (phi->is_Phi() && 2414 C->get_alias_index(phi->as_Phi()->adr_type()) == alias_idx) { 2415 assert(phi->_idx >= nodes_size(), "only new Phi per instance memory slice"); 2416 return phi->as_Phi(); 2417 } 2418 } 2419 } 2420 if (C->live_nodes() + 2*NodeLimitFudgeFactor > C->max_node_limit()) { 2421 if (C->do_escape_analysis() == true && !C->failing()) { 2422 // Retry compilation without escape analysis. 2423 // If this is the first failure, the sentinel string will "stick" 2424 // to the Compile object, and the C2Compiler will see it and retry. 2425 C->record_failure(C2Compiler::retry_no_escape_analysis()); 2426 } 2427 return NULL; 2428 } 2429 orig_phi_worklist.append_if_missing(orig_phi); 2430 const TypePtr *atype = C->get_adr_type(alias_idx); 2431 result = PhiNode::make(orig_phi->in(0), NULL, Type::MEMORY, atype); 2432 C->copy_node_notes_to(result, orig_phi); 2433 igvn->set_type(result, result->bottom_type()); 2434 record_for_optimizer(result); 2435 set_map(orig_phi, result); 2436 new_created = true; 2437 return result; 2438 } 2439 2440 // 2441 // Return a new version of Memory Phi "orig_phi" with the inputs having the 2442 // specified alias index. 2443 // 2444 PhiNode *ConnectionGraph::split_memory_phi(PhiNode *orig_phi, int alias_idx, GrowableArray<PhiNode *> &orig_phi_worklist) { 2445 assert(alias_idx != Compile::AliasIdxBot, "can't split out bottom memory"); 2446 Compile *C = _compile; 2447 PhaseGVN* igvn = _igvn; 2448 bool new_phi_created; 2449 PhiNode *result = create_split_phi(orig_phi, alias_idx, orig_phi_worklist, new_phi_created); 2450 if (!new_phi_created) { 2451 return result; 2452 } 2453 GrowableArray<PhiNode *> phi_list; 2454 GrowableArray<uint> cur_input; 2455 PhiNode *phi = orig_phi; 2456 uint idx = 1; 2457 bool finished = false; 2458 while(!finished) { 2459 while (idx < phi->req()) { 2460 Node *mem = find_inst_mem(phi->in(idx), alias_idx, orig_phi_worklist); 2461 if (mem != NULL && mem->is_Phi()) { 2462 PhiNode *newphi = create_split_phi(mem->as_Phi(), alias_idx, orig_phi_worklist, new_phi_created); 2463 if (new_phi_created) { 2464 // found an phi for which we created a new split, push current one on worklist and begin 2465 // processing new one 2466 phi_list.push(phi); 2467 cur_input.push(idx); 2468 phi = mem->as_Phi(); 2469 result = newphi; 2470 idx = 1; 2471 continue; 2472 } else { 2473 mem = newphi; 2474 } 2475 } 2476 if (C->failing()) { 2477 return NULL; 2478 } 2479 result->set_req(idx++, mem); 2480 } 2481 #ifdef ASSERT 2482 // verify that the new Phi has an input for each input of the original 2483 assert( phi->req() == result->req(), "must have same number of inputs."); 2484 assert( result->in(0) != NULL && result->in(0) == phi->in(0), "regions must match"); 2485 #endif 2486 // Check if all new phi's inputs have specified alias index. 2487 // Otherwise use old phi. 2488 for (uint i = 1; i < phi->req(); i++) { 2489 Node* in = result->in(i); 2490 assert((phi->in(i) == NULL) == (in == NULL), "inputs must correspond."); 2491 } 2492 // we have finished processing a Phi, see if there are any more to do 2493 finished = (phi_list.length() == 0 ); 2494 if (!finished) { 2495 phi = phi_list.pop(); 2496 idx = cur_input.pop(); 2497 PhiNode *prev_result = get_map_phi(phi->_idx); 2498 prev_result->set_req(idx++, result); 2499 result = prev_result; 2500 } 2501 } 2502 return result; 2503 } 2504 2505 // 2506 // The next methods are derived from methods in MemNode. 2507 // 2508 Node* ConnectionGraph::step_through_mergemem(MergeMemNode *mmem, int alias_idx, const TypeOopPtr *toop) { 2509 Node *mem = mmem; 2510 // TypeOopPtr::NOTNULL+any is an OOP with unknown offset - generally 2511 // means an array I have not precisely typed yet. Do not do any 2512 // alias stuff with it any time soon. 2513 if (toop->base() != Type::AnyPtr && 2514 !(toop->klass() != NULL && 2515 toop->klass()->is_java_lang_Object() && 2516 toop->offset() == Type::OffsetBot)) { 2517 mem = mmem->memory_at(alias_idx); 2518 // Update input if it is progress over what we have now 2519 } 2520 return mem; 2521 } 2522 2523 // 2524 // Move memory users to their memory slices. 2525 // 2526 void ConnectionGraph::move_inst_mem(Node* n, GrowableArray<PhiNode *> &orig_phis) { 2527 Compile* C = _compile; 2528 PhaseGVN* igvn = _igvn; 2529 const TypePtr* tp = igvn->type(n->in(MemNode::Address))->isa_ptr(); 2530 assert(tp != NULL, "ptr type"); 2531 int alias_idx = C->get_alias_index(tp); 2532 int general_idx = C->get_general_index(alias_idx); 2533 2534 // Move users first 2535 for (DUIterator_Fast imax, i = n->fast_outs(imax); i < imax; i++) { 2536 Node* use = n->fast_out(i); 2537 if (use->is_MergeMem()) { 2538 MergeMemNode* mmem = use->as_MergeMem(); 2539 assert(n == mmem->memory_at(alias_idx), "should be on instance memory slice"); 2540 if (n != mmem->memory_at(general_idx) || alias_idx == general_idx) { 2541 continue; // Nothing to do 2542 } 2543 // Replace previous general reference to mem node. 2544 uint orig_uniq = C->unique(); 2545 Node* m = find_inst_mem(n, general_idx, orig_phis); 2546 assert(orig_uniq == C->unique(), "no new nodes"); 2547 mmem->set_memory_at(general_idx, m); 2548 --imax; 2549 --i; 2550 } else if (use->is_MemBar()) { 2551 assert(!use->is_Initialize(), "initializing stores should not be moved"); 2552 if (use->req() > MemBarNode::Precedent && 2553 use->in(MemBarNode::Precedent) == n) { 2554 // Don't move related membars. 2555 record_for_optimizer(use); 2556 continue; 2557 } 2558 tp = use->as_MemBar()->adr_type()->isa_ptr(); 2559 if (tp != NULL && C->get_alias_index(tp) == alias_idx || 2560 alias_idx == general_idx) { 2561 continue; // Nothing to do 2562 } 2563 // Move to general memory slice. 2564 uint orig_uniq = C->unique(); 2565 Node* m = find_inst_mem(n, general_idx, orig_phis); 2566 assert(orig_uniq == C->unique(), "no new nodes"); 2567 igvn->hash_delete(use); 2568 imax -= use->replace_edge(n, m); 2569 igvn->hash_insert(use); 2570 record_for_optimizer(use); 2571 --i; 2572 #ifdef ASSERT 2573 } else if (use->is_Mem()) { 2574 if (use->Opcode() == Op_StoreCM && use->in(MemNode::OopStore) == n) { 2575 // Don't move related cardmark. 2576 continue; 2577 } 2578 // Memory nodes should have new memory input. 2579 tp = igvn->type(use->in(MemNode::Address))->isa_ptr(); 2580 assert(tp != NULL, "ptr type"); 2581 int idx = C->get_alias_index(tp); 2582 assert(get_map(use->_idx) != NULL || idx == alias_idx, 2583 "Following memory nodes should have new memory input or be on the same memory slice"); 2584 } else if (use->is_Phi()) { 2585 // Phi nodes should be split and moved already. 2586 tp = use->as_Phi()->adr_type()->isa_ptr(); 2587 assert(tp != NULL, "ptr type"); 2588 int idx = C->get_alias_index(tp); 2589 assert(idx == alias_idx, "Following Phi nodes should be on the same memory slice"); 2590 } else { 2591 use->dump(); 2592 assert(false, "should not be here"); 2593 #endif 2594 } 2595 } 2596 } 2597 2598 // 2599 // Search memory chain of "mem" to find a MemNode whose address 2600 // is the specified alias index. 2601 // 2602 Node* ConnectionGraph::find_inst_mem(Node *orig_mem, int alias_idx, GrowableArray<PhiNode *> &orig_phis) { 2603 if (orig_mem == NULL) 2604 return orig_mem; 2605 Compile* C = _compile; 2606 PhaseGVN* igvn = _igvn; 2607 const TypeOopPtr *toop = C->get_adr_type(alias_idx)->isa_oopptr(); 2608 bool is_instance = (toop != NULL) && toop->is_known_instance(); 2609 Node *start_mem = C->start()->proj_out(TypeFunc::Memory); 2610 Node *prev = NULL; 2611 Node *result = orig_mem; 2612 while (prev != result) { 2613 prev = result; 2614 if (result == start_mem) 2615 break; // hit one of our sentinels 2616 if (result->is_Mem()) { 2617 const Type *at = igvn->type(result->in(MemNode::Address)); 2618 if (at == Type::TOP) 2619 break; // Dead 2620 assert (at->isa_ptr() != NULL, "pointer type required."); 2621 int idx = C->get_alias_index(at->is_ptr()); 2622 if (idx == alias_idx) 2623 break; // Found 2624 if (!is_instance && (at->isa_oopptr() == NULL || 2625 !at->is_oopptr()->is_known_instance())) { 2626 break; // Do not skip store to general memory slice. 2627 } 2628 result = result->in(MemNode::Memory); 2629 } 2630 if (!is_instance) 2631 continue; // don't search further for non-instance types 2632 // skip over a call which does not affect this memory slice 2633 if (result->is_Proj() && result->as_Proj()->_con == TypeFunc::Memory) { 2634 Node *proj_in = result->in(0); 2635 if (proj_in->is_Allocate() && proj_in->_idx == (uint)toop->instance_id()) { 2636 break; // hit one of our sentinels 2637 } else if (proj_in->is_Call()) { 2638 CallNode *call = proj_in->as_Call(); 2639 if (!call->may_modify(toop, igvn)) { 2640 result = call->in(TypeFunc::Memory); 2641 } 2642 } else if (proj_in->is_Initialize()) { 2643 AllocateNode* alloc = proj_in->as_Initialize()->allocation(); 2644 // Stop if this is the initialization for the object instance which 2645 // which contains this memory slice, otherwise skip over it. 2646 if (alloc == NULL || alloc->_idx != (uint)toop->instance_id()) { 2647 result = proj_in->in(TypeFunc::Memory); 2648 } 2649 } else if (proj_in->is_MemBar()) { 2650 result = proj_in->in(TypeFunc::Memory); 2651 } 2652 } else if (result->is_MergeMem()) { 2653 MergeMemNode *mmem = result->as_MergeMem(); 2654 result = step_through_mergemem(mmem, alias_idx, toop); 2655 if (result == mmem->base_memory()) { 2656 // Didn't find instance memory, search through general slice recursively. 2657 result = mmem->memory_at(C->get_general_index(alias_idx)); 2658 result = find_inst_mem(result, alias_idx, orig_phis); 2659 if (C->failing()) { 2660 return NULL; 2661 } 2662 mmem->set_memory_at(alias_idx, result); 2663 } 2664 } else if (result->is_Phi() && 2665 C->get_alias_index(result->as_Phi()->adr_type()) != alias_idx) { 2666 Node *un = result->as_Phi()->unique_input(igvn); 2667 if (un != NULL) { 2668 orig_phis.append_if_missing(result->as_Phi()); 2669 result = un; 2670 } else { 2671 break; 2672 } 2673 } else if (result->is_ClearArray()) { 2674 if (!ClearArrayNode::step_through(&result, (uint)toop->instance_id(), igvn)) { 2675 // Can not bypass initialization of the instance 2676 // we are looking for. 2677 break; 2678 } 2679 // Otherwise skip it (the call updated 'result' value). 2680 } else if (result->Opcode() == Op_SCMemProj) { 2681 Node* mem = result->in(0); 2682 Node* adr = NULL; 2683 if (mem->is_LoadStore()) { 2684 adr = mem->in(MemNode::Address); 2685 } else { 2686 assert(mem->Opcode() == Op_EncodeISOArray, "sanity"); 2687 adr = mem->in(3); // Memory edge corresponds to destination array 2688 } 2689 const Type *at = igvn->type(adr); 2690 if (at != Type::TOP) { 2691 assert (at->isa_ptr() != NULL, "pointer type required."); 2692 int idx = C->get_alias_index(at->is_ptr()); 2693 assert(idx != alias_idx, "Object is not scalar replaceable if a LoadStore node access its field"); 2694 break; 2695 } 2696 result = mem->in(MemNode::Memory); 2697 } 2698 } 2699 if (result->is_Phi()) { 2700 PhiNode *mphi = result->as_Phi(); 2701 assert(mphi->bottom_type() == Type::MEMORY, "memory phi required"); 2702 const TypePtr *t = mphi->adr_type(); 2703 if (!is_instance) { 2704 // Push all non-instance Phis on the orig_phis worklist to update inputs 2705 // during Phase 4 if needed. 2706 orig_phis.append_if_missing(mphi); 2707 } else if (C->get_alias_index(t) != alias_idx) { 2708 // Create a new Phi with the specified alias index type. 2709 result = split_memory_phi(mphi, alias_idx, orig_phis); 2710 } 2711 } 2712 // the result is either MemNode, PhiNode, InitializeNode. 2713 return result; 2714 } 2715 2716 // 2717 // Convert the types of unescaped object to instance types where possible, 2718 // propagate the new type information through the graph, and update memory 2719 // edges and MergeMem inputs to reflect the new type. 2720 // 2721 // We start with allocations (and calls which may be allocations) on alloc_worklist. 2722 // The processing is done in 4 phases: 2723 // 2724 // Phase 1: Process possible allocations from alloc_worklist. Create instance 2725 // types for the CheckCastPP for allocations where possible. 2726 // Propagate the the new types through users as follows: 2727 // casts and Phi: push users on alloc_worklist 2728 // AddP: cast Base and Address inputs to the instance type 2729 // push any AddP users on alloc_worklist and push any memnode 2730 // users onto memnode_worklist. 2731 // Phase 2: Process MemNode's from memnode_worklist. compute new address type and 2732 // search the Memory chain for a store with the appropriate type 2733 // address type. If a Phi is found, create a new version with 2734 // the appropriate memory slices from each of the Phi inputs. 2735 // For stores, process the users as follows: 2736 // MemNode: push on memnode_worklist 2737 // MergeMem: push on mergemem_worklist 2738 // Phase 3: Process MergeMem nodes from mergemem_worklist. Walk each memory slice 2739 // moving the first node encountered of each instance type to the 2740 // the input corresponding to its alias index. 2741 // appropriate memory slice. 2742 // Phase 4: Update the inputs of non-instance memory Phis and the Memory input of memnodes. 2743 // 2744 // In the following example, the CheckCastPP nodes are the cast of allocation 2745 // results and the allocation of node 29 is unescaped and eligible to be an 2746 // instance type. 2747 // 2748 // We start with: 2749 // 2750 // 7 Parm #memory 2751 // 10 ConI "12" 2752 // 19 CheckCastPP "Foo" 2753 // 20 AddP _ 19 19 10 Foo+12 alias_index=4 2754 // 29 CheckCastPP "Foo" 2755 // 30 AddP _ 29 29 10 Foo+12 alias_index=4 2756 // 2757 // 40 StoreP 25 7 20 ... alias_index=4 2758 // 50 StoreP 35 40 30 ... alias_index=4 2759 // 60 StoreP 45 50 20 ... alias_index=4 2760 // 70 LoadP _ 60 30 ... alias_index=4 2761 // 80 Phi 75 50 60 Memory alias_index=4 2762 // 90 LoadP _ 80 30 ... alias_index=4 2763 // 100 LoadP _ 80 20 ... alias_index=4 2764 // 2765 // 2766 // Phase 1 creates an instance type for node 29 assigning it an instance id of 24 2767 // and creating a new alias index for node 30. This gives: 2768 // 2769 // 7 Parm #memory 2770 // 10 ConI "12" 2771 // 19 CheckCastPP "Foo" 2772 // 20 AddP _ 19 19 10 Foo+12 alias_index=4 2773 // 29 CheckCastPP "Foo" iid=24 2774 // 30 AddP _ 29 29 10 Foo+12 alias_index=6 iid=24 2775 // 2776 // 40 StoreP 25 7 20 ... alias_index=4 2777 // 50 StoreP 35 40 30 ... alias_index=6 2778 // 60 StoreP 45 50 20 ... alias_index=4 2779 // 70 LoadP _ 60 30 ... alias_index=6 2780 // 80 Phi 75 50 60 Memory alias_index=4 2781 // 90 LoadP _ 80 30 ... alias_index=6 2782 // 100 LoadP _ 80 20 ... alias_index=4 2783 // 2784 // In phase 2, new memory inputs are computed for the loads and stores, 2785 // And a new version of the phi is created. In phase 4, the inputs to 2786 // node 80 are updated and then the memory nodes are updated with the 2787 // values computed in phase 2. This results in: 2788 // 2789 // 7 Parm #memory 2790 // 10 ConI "12" 2791 // 19 CheckCastPP "Foo" 2792 // 20 AddP _ 19 19 10 Foo+12 alias_index=4 2793 // 29 CheckCastPP "Foo" iid=24 2794 // 30 AddP _ 29 29 10 Foo+12 alias_index=6 iid=24 2795 // 2796 // 40 StoreP 25 7 20 ... alias_index=4 2797 // 50 StoreP 35 7 30 ... alias_index=6 2798 // 60 StoreP 45 40 20 ... alias_index=4 2799 // 70 LoadP _ 50 30 ... alias_index=6 2800 // 80 Phi 75 40 60 Memory alias_index=4 2801 // 120 Phi 75 50 50 Memory alias_index=6 2802 // 90 LoadP _ 120 30 ... alias_index=6 2803 // 100 LoadP _ 80 20 ... alias_index=4 2804 // 2805 void ConnectionGraph::split_unique_types(GrowableArray<Node *> &alloc_worklist) { 2806 GrowableArray<Node *> memnode_worklist; 2807 GrowableArray<PhiNode *> orig_phis; 2808 PhaseIterGVN *igvn = _igvn; 2809 uint new_index_start = (uint) _compile->num_alias_types(); 2810 Arena* arena = Thread::current()->resource_area(); 2811 VectorSet visited(arena); 2812 ideal_nodes.clear(); // Reset for use with set_map/get_map. 2813 uint unique_old = _compile->unique(); 2814 2815 // Phase 1: Process possible allocations from alloc_worklist. 2816 // Create instance types for the CheckCastPP for allocations where possible. 2817 // 2818 // (Note: don't forget to change the order of the second AddP node on 2819 // the alloc_worklist if the order of the worklist processing is changed, 2820 // see the comment in find_second_addp().) 2821 // 2822 while (alloc_worklist.length() != 0) { 2823 Node *n = alloc_worklist.pop(); 2824 uint ni = n->_idx; 2825 if (n->is_Call()) { 2826 CallNode *alloc = n->as_Call(); 2827 // copy escape information to call node 2828 PointsToNode* ptn = ptnode_adr(alloc->_idx); 2829 PointsToNode::EscapeState es = ptn->escape_state(); 2830 // We have an allocation or call which returns a Java object, 2831 // see if it is unescaped. 2832 if (es != PointsToNode::NoEscape || !ptn->scalar_replaceable()) 2833 continue; 2834 // Find CheckCastPP for the allocate or for the return value of a call 2835 n = alloc->result_cast(); 2836 if (n == NULL) { // No uses except Initialize node 2837 if (alloc->is_Allocate()) { 2838 // Set the scalar_replaceable flag for allocation 2839 // so it could be eliminated if it has no uses. 2840 alloc->as_Allocate()->_is_scalar_replaceable = true; 2841 } 2842 if (alloc->is_CallStaticJava()) { 2843 // Set the scalar_replaceable flag for boxing method 2844 // so it could be eliminated if it has no uses. 2845 alloc->as_CallStaticJava()->_is_scalar_replaceable = true; 2846 } 2847 continue; 2848 } 2849 if (!n->is_CheckCastPP()) { // not unique CheckCastPP. 2850 assert(!alloc->is_Allocate(), "allocation should have unique type"); 2851 continue; 2852 } 2853 2854 // The inline code for Object.clone() casts the allocation result to 2855 // java.lang.Object and then to the actual type of the allocated 2856 // object. Detect this case and use the second cast. 2857 // Also detect j.l.reflect.Array.newInstance(jobject, jint) case when 2858 // the allocation result is cast to java.lang.Object and then 2859 // to the actual Array type. 2860 if (alloc->is_Allocate() && n->as_Type()->type() == TypeInstPtr::NOTNULL 2861 && (alloc->is_AllocateArray() || 2862 igvn->type(alloc->in(AllocateNode::KlassNode)) != TypeKlassPtr::OBJECT)) { 2863 Node *cast2 = NULL; 2864 for (DUIterator_Fast imax, i = n->fast_outs(imax); i < imax; i++) { 2865 Node *use = n->fast_out(i); 2866 if (use->is_CheckCastPP()) { 2867 cast2 = use; 2868 break; 2869 } 2870 } 2871 if (cast2 != NULL) { 2872 n = cast2; 2873 } else { 2874 // Non-scalar replaceable if the allocation type is unknown statically 2875 // (reflection allocation), the object can't be restored during 2876 // deoptimization without precise type. 2877 continue; 2878 } 2879 } 2880 2881 const TypeOopPtr *t = igvn->type(n)->isa_oopptr(); 2882 if (t == NULL) 2883 continue; // not a TypeOopPtr 2884 if (!t->klass_is_exact()) 2885 continue; // not an unique type 2886 2887 if (alloc->is_Allocate()) { 2888 // Set the scalar_replaceable flag for allocation 2889 // so it could be eliminated. 2890 alloc->as_Allocate()->_is_scalar_replaceable = true; 2891 } 2892 if (alloc->is_CallStaticJava()) { 2893 // Set the scalar_replaceable flag for boxing method 2894 // so it could be eliminated. 2895 alloc->as_CallStaticJava()->_is_scalar_replaceable = true; 2896 } 2897 set_escape_state(ptnode_adr(n->_idx), es); // CheckCastPP escape state 2898 // in order for an object to be scalar-replaceable, it must be: 2899 // - a direct allocation (not a call returning an object) 2900 // - non-escaping 2901 // - eligible to be a unique type 2902 // - not determined to be ineligible by escape analysis 2903 set_map(alloc, n); 2904 set_map(n, alloc); 2905 const TypeOopPtr* tinst = t->cast_to_instance_id(ni); 2906 igvn->hash_delete(n); 2907 igvn->set_type(n, tinst); 2908 n->raise_bottom_type(tinst); 2909 igvn->hash_insert(n); 2910 record_for_optimizer(n); 2911 if (alloc->is_Allocate() && (t->isa_instptr() || t->isa_aryptr())) { 2912 2913 // First, put on the worklist all Field edges from Connection Graph 2914 // which is more accurate then putting immediate users from Ideal Graph. 2915 for (EdgeIterator e(ptn); e.has_next(); e.next()) { 2916 PointsToNode* tgt = e.get(); 2917 Node* use = tgt->ideal_node(); 2918 assert(tgt->is_Field() && use->is_AddP(), 2919 "only AddP nodes are Field edges in CG"); 2920 if (use->outcnt() > 0) { // Don't process dead nodes 2921 Node* addp2 = find_second_addp(use, use->in(AddPNode::Base)); 2922 if (addp2 != NULL) { 2923 assert(alloc->is_AllocateArray(),"array allocation was expected"); 2924 alloc_worklist.append_if_missing(addp2); 2925 } 2926 alloc_worklist.append_if_missing(use); 2927 } 2928 } 2929 2930 // An allocation may have an Initialize which has raw stores. Scan 2931 // the users of the raw allocation result and push AddP users 2932 // on alloc_worklist. 2933 Node *raw_result = alloc->proj_out(TypeFunc::Parms); 2934 assert (raw_result != NULL, "must have an allocation result"); 2935 for (DUIterator_Fast imax, i = raw_result->fast_outs(imax); i < imax; i++) { 2936 Node *use = raw_result->fast_out(i); 2937 if (use->is_AddP() && use->outcnt() > 0) { // Don't process dead nodes 2938 Node* addp2 = find_second_addp(use, raw_result); 2939 if (addp2 != NULL) { 2940 assert(alloc->is_AllocateArray(),"array allocation was expected"); 2941 alloc_worklist.append_if_missing(addp2); 2942 } 2943 alloc_worklist.append_if_missing(use); 2944 } else if (use->is_MemBar()) { 2945 memnode_worklist.append_if_missing(use); 2946 } 2947 } 2948 } 2949 } else if (n->is_AddP()) { 2950 JavaObjectNode* jobj = unique_java_object(get_addp_base(n)); 2951 if (jobj == NULL || jobj == phantom_obj) { 2952 #ifdef ASSERT 2953 ptnode_adr(get_addp_base(n)->_idx)->dump(); 2954 ptnode_adr(n->_idx)->dump(); 2955 assert(jobj != NULL && jobj != phantom_obj, "escaped allocation"); 2956 #endif 2957 _compile->record_failure(C2Compiler::retry_no_escape_analysis()); 2958 return; 2959 } 2960 Node *base = get_map(jobj->idx()); // CheckCastPP node 2961 if (!split_AddP(n, base)) continue; // wrong type from dead path 2962 } else if (n->is_Phi() || 2963 n->is_CheckCastPP() || 2964 n->is_EncodeP() || 2965 n->is_DecodeN() || 2966 (n->is_ConstraintCast() && n->Opcode() == Op_CastPP)) { 2967 if (visited.test_set(n->_idx)) { 2968 assert(n->is_Phi(), "loops only through Phi's"); 2969 continue; // already processed 2970 } 2971 JavaObjectNode* jobj = unique_java_object(n); 2972 if (jobj == NULL || jobj == phantom_obj) { 2973 #ifdef ASSERT 2974 ptnode_adr(n->_idx)->dump(); 2975 assert(jobj != NULL && jobj != phantom_obj, "escaped allocation"); 2976 #endif 2977 _compile->record_failure(C2Compiler::retry_no_escape_analysis()); 2978 return; 2979 } else { 2980 Node *val = get_map(jobj->idx()); // CheckCastPP node 2981 TypeNode *tn = n->as_Type(); 2982 const TypeOopPtr* tinst = igvn->type(val)->isa_oopptr(); 2983 assert(tinst != NULL && tinst->is_known_instance() && 2984 tinst->instance_id() == jobj->idx() , "instance type expected."); 2985 2986 const Type *tn_type = igvn->type(tn); 2987 const TypeOopPtr *tn_t; 2988 if (tn_type->isa_narrowoop()) { 2989 tn_t = tn_type->make_ptr()->isa_oopptr(); 2990 } else { 2991 tn_t = tn_type->isa_oopptr(); 2992 } 2993 if (tn_t != NULL && tinst->klass()->is_subtype_of(tn_t->klass())) { 2994 if (tn_type->isa_narrowoop()) { 2995 tn_type = tinst->make_narrowoop(); 2996 } else { 2997 tn_type = tinst; 2998 } 2999 igvn->hash_delete(tn); 3000 igvn->set_type(tn, tn_type); 3001 tn->set_type(tn_type); 3002 igvn->hash_insert(tn); 3003 record_for_optimizer(n); 3004 } else { 3005 assert(tn_type == TypePtr::NULL_PTR || 3006 tn_t != NULL && !tinst->klass()->is_subtype_of(tn_t->klass()), 3007 "unexpected type"); 3008 continue; // Skip dead path with different type 3009 } 3010 } 3011 } else { 3012 debug_only(n->dump();) 3013 assert(false, "EA: unexpected node"); 3014 continue; 3015 } 3016 // push allocation's users on appropriate worklist 3017 for (DUIterator_Fast imax, i = n->fast_outs(imax); i < imax; i++) { 3018 Node *use = n->fast_out(i); 3019 if(use->is_Mem() && use->in(MemNode::Address) == n) { 3020 // Load/store to instance's field 3021 memnode_worklist.append_if_missing(use); 3022 } else if (use->is_MemBar()) { 3023 if (use->in(TypeFunc::Memory) == n) { // Ignore precedent edge 3024 memnode_worklist.append_if_missing(use); 3025 } 3026 } else if (use->is_AddP() && use->outcnt() > 0) { // No dead nodes 3027 Node* addp2 = find_second_addp(use, n); 3028 if (addp2 != NULL) { 3029 alloc_worklist.append_if_missing(addp2); 3030 } 3031 alloc_worklist.append_if_missing(use); 3032 } else if (use->is_Phi() || 3033 use->is_CheckCastPP() || 3034 use->is_EncodeNarrowPtr() || 3035 use->is_DecodeNarrowPtr() || 3036 (use->is_ConstraintCast() && use->Opcode() == Op_CastPP)) { 3037 alloc_worklist.append_if_missing(use); 3038 #ifdef ASSERT 3039 } else if (use->is_Mem()) { 3040 assert(use->in(MemNode::Address) != n, "EA: missing allocation reference path"); 3041 } else if (use->is_MergeMem()) { 3042 assert(_mergemem_worklist.contains(use->as_MergeMem()), "EA: missing MergeMem node in the worklist"); 3043 } else if (use->is_SafePoint()) { 3044 // Look for MergeMem nodes for calls which reference unique allocation 3045 // (through CheckCastPP nodes) even for debug info. 3046 Node* m = use->in(TypeFunc::Memory); 3047 if (m->is_MergeMem()) { 3048 assert(_mergemem_worklist.contains(m->as_MergeMem()), "EA: missing MergeMem node in the worklist"); 3049 } 3050 } else if (use->Opcode() == Op_EncodeISOArray) { 3051 if (use->in(MemNode::Memory) == n || use->in(3) == n) { 3052 // EncodeISOArray overwrites destination array 3053 memnode_worklist.append_if_missing(use); 3054 } 3055 } else { 3056 uint op = use->Opcode(); 3057 if (!(op == Op_CmpP || op == Op_Conv2B || 3058 op == Op_CastP2X || op == Op_StoreCM || 3059 op == Op_FastLock || op == Op_AryEq || op == Op_StrComp || 3060 op == Op_StrEquals || op == Op_StrIndexOf)) { 3061 n->dump(); 3062 use->dump(); 3063 assert(false, "EA: missing allocation reference path"); 3064 } 3065 #endif 3066 } 3067 } 3068 3069 } 3070 // New alias types were created in split_AddP(). 3071 uint new_index_end = (uint) _compile->num_alias_types(); 3072 assert(unique_old == _compile->unique(), "there should be no new ideal nodes after Phase 1"); 3073 3074 // Phase 2: Process MemNode's from memnode_worklist. compute new address type and 3075 // compute new values for Memory inputs (the Memory inputs are not 3076 // actually updated until phase 4.) 3077 if (memnode_worklist.length() == 0) 3078 return; // nothing to do 3079 while (memnode_worklist.length() != 0) { 3080 Node *n = memnode_worklist.pop(); 3081 if (visited.test_set(n->_idx)) 3082 continue; 3083 if (n->is_Phi() || n->is_ClearArray()) { 3084 // we don't need to do anything, but the users must be pushed 3085 } else if (n->is_MemBar()) { // Initialize, MemBar nodes 3086 // we don't need to do anything, but the users must be pushed 3087 n = n->as_MemBar()->proj_out(TypeFunc::Memory); 3088 if (n == NULL) 3089 continue; 3090 } else if (n->Opcode() == Op_EncodeISOArray) { 3091 // get the memory projection 3092 for (DUIterator_Fast imax, i = n->fast_outs(imax); i < imax; i++) { 3093 Node *use = n->fast_out(i); 3094 if (use->Opcode() == Op_SCMemProj) { 3095 n = use; 3096 break; 3097 } 3098 } 3099 assert(n->Opcode() == Op_SCMemProj, "memory projection required"); 3100 } else { 3101 assert(n->is_Mem(), "memory node required."); 3102 Node *addr = n->in(MemNode::Address); 3103 const Type *addr_t = igvn->type(addr); 3104 if (addr_t == Type::TOP) 3105 continue; 3106 assert (addr_t->isa_ptr() != NULL, "pointer type required."); 3107 int alias_idx = _compile->get_alias_index(addr_t->is_ptr()); 3108 assert ((uint)alias_idx < new_index_end, "wrong alias index"); 3109 Node *mem = find_inst_mem(n->in(MemNode::Memory), alias_idx, orig_phis); 3110 if (_compile->failing()) { 3111 return; 3112 } 3113 if (mem != n->in(MemNode::Memory)) { 3114 // We delay the memory edge update since we need old one in 3115 // MergeMem code below when instances memory slices are separated. 3116 set_map(n, mem); 3117 } 3118 if (n->is_Load()) { 3119 continue; // don't push users 3120 } else if (n->is_LoadStore()) { 3121 // get the memory projection 3122 for (DUIterator_Fast imax, i = n->fast_outs(imax); i < imax; i++) { 3123 Node *use = n->fast_out(i); 3124 if (use->Opcode() == Op_SCMemProj) { 3125 n = use; 3126 break; 3127 } 3128 } 3129 assert(n->Opcode() == Op_SCMemProj, "memory projection required"); 3130 } 3131 } 3132 // push user on appropriate worklist 3133 for (DUIterator_Fast imax, i = n->fast_outs(imax); i < imax; i++) { 3134 Node *use = n->fast_out(i); 3135 if (use->is_Phi() || use->is_ClearArray()) { 3136 memnode_worklist.append_if_missing(use); 3137 } else if (use->is_Mem() && use->in(MemNode::Memory) == n) { 3138 if (use->Opcode() == Op_StoreCM) // Ignore cardmark stores 3139 continue; 3140 memnode_worklist.append_if_missing(use); 3141 } else if (use->is_MemBar()) { 3142 if (use->in(TypeFunc::Memory) == n) { // Ignore precedent edge 3143 memnode_worklist.append_if_missing(use); 3144 } 3145 #ifdef ASSERT 3146 } else if(use->is_Mem()) { 3147 assert(use->in(MemNode::Memory) != n, "EA: missing memory path"); 3148 } else if (use->is_MergeMem()) { 3149 assert(_mergemem_worklist.contains(use->as_MergeMem()), "EA: missing MergeMem node in the worklist"); 3150 } else if (use->Opcode() == Op_EncodeISOArray) { 3151 if (use->in(MemNode::Memory) == n || use->in(3) == n) { 3152 // EncodeISOArray overwrites destination array 3153 memnode_worklist.append_if_missing(use); 3154 } 3155 } else { 3156 uint op = use->Opcode(); 3157 if (!(op == Op_StoreCM || 3158 (op == Op_CallLeaf && use->as_CallLeaf()->_name != NULL && 3159 strcmp(use->as_CallLeaf()->_name, "g1_wb_pre") == 0) || 3160 op == Op_AryEq || op == Op_StrComp || 3161 op == Op_StrEquals || op == Op_StrIndexOf)) { 3162 n->dump(); 3163 use->dump(); 3164 assert(false, "EA: missing memory path"); 3165 } 3166 #endif 3167 } 3168 } 3169 } 3170 3171 // Phase 3: Process MergeMem nodes from mergemem_worklist. 3172 // Walk each memory slice moving the first node encountered of each 3173 // instance type to the the input corresponding to its alias index. 3174 uint length = _mergemem_worklist.length(); 3175 for( uint next = 0; next < length; ++next ) { 3176 MergeMemNode* nmm = _mergemem_worklist.at(next); 3177 assert(!visited.test_set(nmm->_idx), "should not be visited before"); 3178 // Note: we don't want to use MergeMemStream here because we only want to 3179 // scan inputs which exist at the start, not ones we add during processing. 3180 // Note 2: MergeMem may already contains instance memory slices added 3181 // during find_inst_mem() call when memory nodes were processed above. 3182 igvn->hash_delete(nmm); 3183 uint nslices = nmm->req(); 3184 for (uint i = Compile::AliasIdxRaw+1; i < nslices; i++) { 3185 Node* mem = nmm->in(i); 3186 Node* cur = NULL; 3187 if (mem == NULL || mem->is_top()) 3188 continue; 3189 // First, update mergemem by moving memory nodes to corresponding slices 3190 // if their type became more precise since this mergemem was created. 3191 while (mem->is_Mem()) { 3192 const Type *at = igvn->type(mem->in(MemNode::Address)); 3193 if (at != Type::TOP) { 3194 assert (at->isa_ptr() != NULL, "pointer type required."); 3195 uint idx = (uint)_compile->get_alias_index(at->is_ptr()); 3196 if (idx == i) { 3197 if (cur == NULL) 3198 cur = mem; 3199 } else { 3200 if (idx >= nmm->req() || nmm->is_empty_memory(nmm->in(idx))) { 3201 nmm->set_memory_at(idx, mem); 3202 } 3203 } 3204 } 3205 mem = mem->in(MemNode::Memory); 3206 } 3207 nmm->set_memory_at(i, (cur != NULL) ? cur : mem); 3208 // Find any instance of the current type if we haven't encountered 3209 // already a memory slice of the instance along the memory chain. 3210 for (uint ni = new_index_start; ni < new_index_end; ni++) { 3211 if((uint)_compile->get_general_index(ni) == i) { 3212 Node *m = (ni >= nmm->req()) ? nmm->empty_memory() : nmm->in(ni); 3213 if (nmm->is_empty_memory(m)) { 3214 Node* result = find_inst_mem(mem, ni, orig_phis); 3215 if (_compile->failing()) { 3216 return; 3217 } 3218 nmm->set_memory_at(ni, result); 3219 } 3220 } 3221 } 3222 } 3223 // Find the rest of instances values 3224 for (uint ni = new_index_start; ni < new_index_end; ni++) { 3225 const TypeOopPtr *tinst = _compile->get_adr_type(ni)->isa_oopptr(); 3226 Node* result = step_through_mergemem(nmm, ni, tinst); 3227 if (result == nmm->base_memory()) { 3228 // Didn't find instance memory, search through general slice recursively. 3229 result = nmm->memory_at(_compile->get_general_index(ni)); 3230 result = find_inst_mem(result, ni, orig_phis); 3231 if (_compile->failing()) { 3232 return; 3233 } 3234 nmm->set_memory_at(ni, result); 3235 } 3236 } 3237 igvn->hash_insert(nmm); 3238 record_for_optimizer(nmm); 3239 } 3240 3241 // Phase 4: Update the inputs of non-instance memory Phis and 3242 // the Memory input of memnodes 3243 // First update the inputs of any non-instance Phi's from 3244 // which we split out an instance Phi. Note we don't have 3245 // to recursively process Phi's encounted on the input memory 3246 // chains as is done in split_memory_phi() since they will 3247 // also be processed here. 3248 for (int j = 0; j < orig_phis.length(); j++) { 3249 PhiNode *phi = orig_phis.at(j); 3250 int alias_idx = _compile->get_alias_index(phi->adr_type()); 3251 igvn->hash_delete(phi); 3252 for (uint i = 1; i < phi->req(); i++) { 3253 Node *mem = phi->in(i); 3254 Node *new_mem = find_inst_mem(mem, alias_idx, orig_phis); 3255 if (_compile->failing()) { 3256 return; 3257 } 3258 if (mem != new_mem) { 3259 phi->set_req(i, new_mem); 3260 } 3261 } 3262 igvn->hash_insert(phi); 3263 record_for_optimizer(phi); 3264 } 3265 3266 // Update the memory inputs of MemNodes with the value we computed 3267 // in Phase 2 and move stores memory users to corresponding memory slices. 3268 // Disable memory split verification code until the fix for 6984348. 3269 // Currently it produces false negative results since it does not cover all cases. 3270 #if 0 // ifdef ASSERT 3271 visited.Reset(); 3272 Node_Stack old_mems(arena, _compile->unique() >> 2); 3273 #endif 3274 for (uint i = 0; i < ideal_nodes.size(); i++) { 3275 Node* n = ideal_nodes.at(i); 3276 Node* nmem = get_map(n->_idx); 3277 assert(nmem != NULL, "sanity"); 3278 if (n->is_Mem()) { 3279 #if 0 // ifdef ASSERT 3280 Node* old_mem = n->in(MemNode::Memory); 3281 if (!visited.test_set(old_mem->_idx)) { 3282 old_mems.push(old_mem, old_mem->outcnt()); 3283 } 3284 #endif 3285 assert(n->in(MemNode::Memory) != nmem, "sanity"); 3286 if (!n->is_Load()) { 3287 // Move memory users of a store first. 3288 move_inst_mem(n, orig_phis); 3289 } 3290 // Now update memory input 3291 igvn->hash_delete(n); 3292 n->set_req(MemNode::Memory, nmem); 3293 igvn->hash_insert(n); 3294 record_for_optimizer(n); 3295 } else { 3296 assert(n->is_Allocate() || n->is_CheckCastPP() || 3297 n->is_AddP() || n->is_Phi(), "unknown node used for set_map()"); 3298 } 3299 } 3300 #if 0 // ifdef ASSERT 3301 // Verify that memory was split correctly 3302 while (old_mems.is_nonempty()) { 3303 Node* old_mem = old_mems.node(); 3304 uint old_cnt = old_mems.index(); 3305 old_mems.pop(); 3306 assert(old_cnt == old_mem->outcnt(), "old mem could be lost"); 3307 } 3308 #endif 3309 } 3310 3311 #ifndef PRODUCT 3312 static const char *node_type_names[] = { 3313 "UnknownType", 3314 "JavaObject", 3315 "LocalVar", 3316 "Field", 3317 "Arraycopy" 3318 }; 3319 3320 static const char *esc_names[] = { 3321 "UnknownEscape", 3322 "NoEscape", 3323 "ArgEscape", 3324 "GlobalEscape" 3325 }; 3326 3327 void PointsToNode::dump(bool print_state) const { 3328 NodeType nt = node_type(); 3329 tty->print("%s ", node_type_names[(int) nt]); 3330 if (print_state) { 3331 EscapeState es = escape_state(); 3332 EscapeState fields_es = fields_escape_state(); 3333 tty->print("%s(%s) ", esc_names[(int)es], esc_names[(int)fields_es]); 3334 if (nt == PointsToNode::JavaObject && !this->scalar_replaceable()) 3335 tty->print("NSR "); 3336 } 3337 if (is_Field()) { 3338 FieldNode* f = (FieldNode*)this; 3339 if (f->is_oop()) 3340 tty->print("oop "); 3341 if (f->offset() > 0) 3342 tty->print("+%d ", f->offset()); 3343 tty->print("("); 3344 for (BaseIterator i(f); i.has_next(); i.next()) { 3345 PointsToNode* b = i.get(); 3346 tty->print(" %d%s", b->idx(),(b->is_JavaObject() ? "P" : "")); 3347 } 3348 tty->print(" )"); 3349 } 3350 tty->print("["); 3351 for (EdgeIterator i(this); i.has_next(); i.next()) { 3352 PointsToNode* e = i.get(); 3353 tty->print(" %d%s%s", e->idx(),(e->is_JavaObject() ? "P" : (e->is_Field() ? "F" : "")), e->is_Arraycopy() ? "cp" : ""); 3354 } 3355 tty->print(" ["); 3356 for (UseIterator i(this); i.has_next(); i.next()) { 3357 PointsToNode* u = i.get(); 3358 bool is_base = false; 3359 if (PointsToNode::is_base_use(u)) { 3360 is_base = true; 3361 u = PointsToNode::get_use_node(u)->as_Field(); 3362 } 3363 tty->print(" %d%s%s", u->idx(), is_base ? "b" : "", u->is_Arraycopy() ? "cp" : ""); 3364 } 3365 tty->print(" ]] "); 3366 if (_node == NULL) 3367 tty->print_cr("<null>"); 3368 else 3369 _node->dump(); 3370 } 3371 3372 void ConnectionGraph::dump(GrowableArray<PointsToNode*>& ptnodes_worklist) { 3373 bool first = true; 3374 int ptnodes_length = ptnodes_worklist.length(); 3375 for (int i = 0; i < ptnodes_length; i++) { 3376 PointsToNode *ptn = ptnodes_worklist.at(i); 3377 if (ptn == NULL || !ptn->is_JavaObject()) 3378 continue; 3379 PointsToNode::EscapeState es = ptn->escape_state(); 3380 if ((es != PointsToNode::NoEscape) && !Verbose) { 3381 continue; 3382 } 3383 Node* n = ptn->ideal_node(); 3384 if (n->is_Allocate() || (n->is_CallStaticJava() && 3385 n->as_CallStaticJava()->is_boxing_method())) { 3386 if (first) { 3387 tty->cr(); 3388 tty->print("======== Connection graph for "); 3389 _compile->method()->print_short_name(); 3390 tty->cr(); 3391 first = false; 3392 } 3393 ptn->dump(); 3394 // Print all locals and fields which reference this allocation 3395 for (UseIterator j(ptn); j.has_next(); j.next()) { 3396 PointsToNode* use = j.get(); 3397 if (use->is_LocalVar()) { 3398 use->dump(Verbose); 3399 } else if (Verbose) { 3400 use->dump(); 3401 } 3402 } 3403 tty->cr(); 3404 } 3405 } 3406 } 3407 #endif