1 /* 2 * Copyright (c) 2005, 2015, 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 // Bytecode analyzer BCEscapeAnalyzer, used for Call nodes 210 // processing, calls to CI to resolve symbols (types, fields, methods) 211 // referenced in bytecode. During symbol resolution VM may throw 212 // an exception which CI cleans and converts to compilation failure. 213 if (C->failing()) return false; 214 215 // 2. Finish Graph construction by propagating references to all 216 // java objects through graph. 217 if (!complete_connection_graph(ptnodes_worklist, non_escaped_worklist, 218 java_objects_worklist, oop_fields_worklist)) { 219 // All objects escaped or hit time or iterations limits. 220 _collecting = false; 221 return false; 222 } 223 224 // 3. Adjust scalar_replaceable state of nonescaping objects and push 225 // scalar replaceable allocations on alloc_worklist for processing 226 // in split_unique_types(). 227 int non_escaped_length = non_escaped_worklist.length(); 228 for (int next = 0; next < non_escaped_length; next++) { 229 JavaObjectNode* ptn = non_escaped_worklist.at(next); 230 bool noescape = (ptn->escape_state() == PointsToNode::NoEscape); 231 Node* n = ptn->ideal_node(); 232 if (n->is_Allocate()) { 233 n->as_Allocate()->_is_non_escaping = noescape; 234 } 235 if (n->is_CallStaticJava()) { 236 n->as_CallStaticJava()->_is_non_escaping = noescape; 237 } 238 if (noescape && ptn->scalar_replaceable()) { 239 adjust_scalar_replaceable_state(ptn); 240 if (ptn->scalar_replaceable()) { 241 alloc_worklist.append(ptn->ideal_node()); 242 } 243 } 244 } 245 246 #ifdef ASSERT 247 if (VerifyConnectionGraph) { 248 // Verify that graph is complete - no new edges could be added or needed. 249 verify_connection_graph(ptnodes_worklist, non_escaped_worklist, 250 java_objects_worklist, addp_worklist); 251 } 252 assert(C->unique() == nodes_size(), "no new ideal nodes should be added during ConnectionGraph build"); 253 assert(null_obj->escape_state() == PointsToNode::NoEscape && 254 null_obj->edge_count() == 0 && 255 !null_obj->arraycopy_src() && 256 !null_obj->arraycopy_dst(), "sanity"); 257 #endif 258 259 _collecting = false; 260 261 } // TracePhase t3("connectionGraph") 262 263 // 4. Optimize ideal graph based on EA information. 264 bool has_non_escaping_obj = (non_escaped_worklist.length() > 0); 265 if (has_non_escaping_obj) { 266 optimize_ideal_graph(ptr_cmp_worklist, storestore_worklist); 267 } 268 269 #ifndef PRODUCT 270 if (PrintEscapeAnalysis) { 271 dump(ptnodes_worklist); // Dump ConnectionGraph 272 } 273 #endif 274 275 bool has_scalar_replaceable_candidates = (alloc_worklist.length() > 0); 276 #ifdef ASSERT 277 if (VerifyConnectionGraph) { 278 int alloc_length = alloc_worklist.length(); 279 for (int next = 0; next < alloc_length; ++next) { 280 Node* n = alloc_worklist.at(next); 281 PointsToNode* ptn = ptnode_adr(n->_idx); 282 assert(ptn->escape_state() == PointsToNode::NoEscape && ptn->scalar_replaceable(), "sanity"); 283 } 284 } 285 #endif 286 287 // 5. Separate memory graph for scalar replaceable allcations. 288 if (has_scalar_replaceable_candidates && 289 C->AliasLevel() >= 3 && EliminateAllocations) { 290 // Now use the escape information to create unique types for 291 // scalar replaceable objects. 292 split_unique_types(alloc_worklist); 293 if (C->failing()) return false; 294 C->print_method(PHASE_AFTER_EA, 2); 295 296 #ifdef ASSERT 297 } else if (Verbose && (PrintEscapeAnalysis || PrintEliminateAllocations)) { 298 tty->print("=== No allocations eliminated for "); 299 C->method()->print_short_name(); 300 if(!EliminateAllocations) { 301 tty->print(" since EliminateAllocations is off ==="); 302 } else if(!has_scalar_replaceable_candidates) { 303 tty->print(" since there are no scalar replaceable candidates ==="); 304 } else if(C->AliasLevel() < 3) { 305 tty->print(" since AliasLevel < 3 ==="); 306 } 307 tty->cr(); 308 #endif 309 } 310 return has_non_escaping_obj; 311 } 312 313 // Utility function for nodes that load an object 314 void ConnectionGraph::add_objload_to_connection_graph(Node *n, Unique_Node_List *delayed_worklist) { 315 // Using isa_ptr() instead of isa_oopptr() for LoadP and Phi because 316 // ThreadLocal has RawPtr type. 317 const Type* t = _igvn->type(n); 318 if (t->make_ptr() != NULL) { 319 Node* adr = n->in(MemNode::Address); 320 #ifdef ASSERT 321 if (!adr->is_AddP()) { 322 assert(_igvn->type(adr)->isa_rawptr(), "sanity"); 323 } else { 324 assert((ptnode_adr(adr->_idx) == NULL || 325 ptnode_adr(adr->_idx)->as_Field()->is_oop()), "sanity"); 326 } 327 #endif 328 add_local_var_and_edge(n, PointsToNode::NoEscape, 329 adr, delayed_worklist); 330 } 331 } 332 333 // Populate Connection Graph with PointsTo nodes and create simple 334 // connection graph edges. 335 void ConnectionGraph::add_node_to_connection_graph(Node *n, Unique_Node_List *delayed_worklist) { 336 assert(!_verify, "this method sould not be called for verification"); 337 PhaseGVN* igvn = _igvn; 338 uint n_idx = n->_idx; 339 PointsToNode* n_ptn = ptnode_adr(n_idx); 340 if (n_ptn != NULL) 341 return; // No need to redefine PointsTo node during first iteration. 342 343 if (n->is_Call()) { 344 // Arguments to allocation and locking don't escape. 345 if (n->is_AbstractLock()) { 346 // Put Lock and Unlock nodes on IGVN worklist to process them during 347 // first IGVN optimization when escape information is still available. 348 record_for_optimizer(n); 349 } else if (n->is_Allocate()) { 350 add_call_node(n->as_Call()); 351 record_for_optimizer(n); 352 } else { 353 if (n->is_CallStaticJava()) { 354 const char* name = n->as_CallStaticJava()->_name; 355 if (name != NULL && strcmp(name, "uncommon_trap") == 0) 356 return; // Skip uncommon traps 357 } 358 // Don't mark as processed since call's arguments have to be processed. 359 delayed_worklist->push(n); 360 // Check if a call returns an object. 361 if ((n->as_Call()->returns_pointer() && 362 n->as_Call()->proj_out(TypeFunc::Parms) != NULL) || 363 (n->is_CallStaticJava() && 364 n->as_CallStaticJava()->is_boxing_method())) { 365 add_call_node(n->as_Call()); 366 } 367 } 368 return; 369 } 370 // Put this check here to process call arguments since some call nodes 371 // point to phantom_obj. 372 if (n_ptn == phantom_obj || n_ptn == null_obj) 373 return; // Skip predefined nodes. 374 375 int opcode = n->Opcode(); 376 switch (opcode) { 377 case Op_AddP: { 378 Node* base = get_addp_base(n); 379 PointsToNode* ptn_base = ptnode_adr(base->_idx); 380 // Field nodes are created for all field types. They are used in 381 // adjust_scalar_replaceable_state() and split_unique_types(). 382 // Note, non-oop fields will have only base edges in Connection 383 // Graph because such fields are not used for oop loads and stores. 384 int offset = address_offset(n, igvn); 385 add_field(n, PointsToNode::NoEscape, offset); 386 if (ptn_base == NULL) { 387 delayed_worklist->push(n); // Process it later. 388 } else { 389 n_ptn = ptnode_adr(n_idx); 390 add_base(n_ptn->as_Field(), ptn_base); 391 } 392 break; 393 } 394 case Op_CastX2P: { 395 map_ideal_node(n, phantom_obj); 396 break; 397 } 398 case Op_CastPP: 399 case Op_CheckCastPP: 400 case Op_EncodeP: 401 case Op_DecodeN: 402 case Op_EncodePKlass: 403 case Op_DecodeNKlass: { 404 add_local_var_and_edge(n, PointsToNode::NoEscape, 405 n->in(1), delayed_worklist); 406 break; 407 } 408 case Op_CMoveP: { 409 add_local_var(n, PointsToNode::NoEscape); 410 // Do not add edges during first iteration because some could be 411 // not defined yet. 412 delayed_worklist->push(n); 413 break; 414 } 415 case Op_ConP: 416 case Op_ConN: 417 case Op_ConNKlass: { 418 // assume all oop constants globally escape except for null 419 PointsToNode::EscapeState es; 420 const Type* t = igvn->type(n); 421 if (t == TypePtr::NULL_PTR || t == TypeNarrowOop::NULL_PTR) { 422 es = PointsToNode::NoEscape; 423 } else { 424 es = PointsToNode::GlobalEscape; 425 } 426 add_java_object(n, es); 427 break; 428 } 429 case Op_CreateEx: { 430 // assume that all exception objects globally escape 431 map_ideal_node(n, phantom_obj); 432 break; 433 } 434 case Op_LoadKlass: 435 case Op_LoadNKlass: { 436 // Unknown class is loaded 437 map_ideal_node(n, phantom_obj); 438 break; 439 } 440 case Op_LoadP: 441 case Op_LoadN: 442 case Op_LoadPLocked: { 443 add_objload_to_connection_graph(n, delayed_worklist); 444 break; 445 } 446 case Op_Parm: { 447 map_ideal_node(n, phantom_obj); 448 break; 449 } 450 case Op_PartialSubtypeCheck: { 451 // Produces Null or notNull and is used in only in CmpP so 452 // phantom_obj could be used. 453 map_ideal_node(n, phantom_obj); // Result is unknown 454 break; 455 } 456 case Op_Phi: { 457 // Using isa_ptr() instead of isa_oopptr() for LoadP and Phi because 458 // ThreadLocal has RawPtr type. 459 const Type* t = n->as_Phi()->type(); 460 if (t->make_ptr() != NULL) { 461 add_local_var(n, PointsToNode::NoEscape); 462 // Do not add edges during first iteration because some could be 463 // not defined yet. 464 delayed_worklist->push(n); 465 } 466 break; 467 } 468 case Op_Proj: { 469 // we are only interested in the oop result projection from a call 470 if (n->as_Proj()->_con == TypeFunc::Parms && n->in(0)->is_Call() && 471 n->in(0)->as_Call()->returns_pointer()) { 472 add_local_var_and_edge(n, PointsToNode::NoEscape, 473 n->in(0), delayed_worklist); 474 } 475 break; 476 } 477 case Op_Rethrow: // Exception object escapes 478 case Op_Return: { 479 if (n->req() > TypeFunc::Parms && 480 igvn->type(n->in(TypeFunc::Parms))->isa_oopptr()) { 481 // Treat Return value as LocalVar with GlobalEscape escape state. 482 add_local_var_and_edge(n, PointsToNode::GlobalEscape, 483 n->in(TypeFunc::Parms), delayed_worklist); 484 } 485 break; 486 } 487 case Op_GetAndSetP: 488 case Op_GetAndSetN: { 489 add_objload_to_connection_graph(n, delayed_worklist); 490 // fallthrough 491 } 492 case Op_StoreP: 493 case Op_StoreN: 494 case Op_StoreNKlass: 495 case Op_StorePConditional: 496 case Op_CompareAndSwapP: 497 case Op_CompareAndSwapN: { 498 Node* adr = n->in(MemNode::Address); 499 const Type *adr_type = igvn->type(adr); 500 adr_type = adr_type->make_ptr(); 501 if (adr_type == NULL) { 502 break; // skip dead nodes 503 } 504 if (adr_type->isa_oopptr() || 505 (opcode == Op_StoreP || opcode == Op_StoreN || opcode == Op_StoreNKlass) && 506 (adr_type == TypeRawPtr::NOTNULL && 507 adr->in(AddPNode::Address)->is_Proj() && 508 adr->in(AddPNode::Address)->in(0)->is_Allocate())) { 509 delayed_worklist->push(n); // Process it later. 510 #ifdef ASSERT 511 assert(adr->is_AddP(), "expecting an AddP"); 512 if (adr_type == TypeRawPtr::NOTNULL) { 513 // Verify a raw address for a store captured by Initialize node. 514 int offs = (int)igvn->find_intptr_t_con(adr->in(AddPNode::Offset), Type::OffsetBot); 515 assert(offs != Type::OffsetBot, "offset must be a constant"); 516 } 517 #endif 518 } else { 519 // Ignore copy the displaced header to the BoxNode (OSR compilation). 520 if (adr->is_BoxLock()) 521 break; 522 // Stored value escapes in unsafe access. 523 if ((opcode == Op_StoreP) && (adr_type == TypeRawPtr::BOTTOM)) { 524 // Pointer stores in G1 barriers looks like unsafe access. 525 // Ignore such stores to be able scalar replace non-escaping 526 // allocations. 527 if (UseG1GC && adr->is_AddP()) { 528 Node* base = get_addp_base(adr); 529 if (base->Opcode() == Op_LoadP && 530 base->in(MemNode::Address)->is_AddP()) { 531 adr = base->in(MemNode::Address); 532 Node* tls = get_addp_base(adr); 533 if (tls->Opcode() == Op_ThreadLocal) { 534 int offs = (int)igvn->find_intptr_t_con(adr->in(AddPNode::Offset), Type::OffsetBot); 535 if (offs == in_bytes(JavaThread::satb_mark_queue_offset() + 536 PtrQueue::byte_offset_of_buf())) { 537 break; // G1 pre barier previous oop value store. 538 } 539 if (offs == in_bytes(JavaThread::dirty_card_queue_offset() + 540 PtrQueue::byte_offset_of_buf())) { 541 break; // G1 post barier card address store. 542 } 543 } 544 } 545 } 546 delayed_worklist->push(n); // Process unsafe access later. 547 break; 548 } 549 #ifdef ASSERT 550 n->dump(1); 551 assert(false, "not unsafe or G1 barrier raw StoreP"); 552 #endif 553 } 554 break; 555 } 556 case Op_AryEq: 557 case Op_StrComp: 558 case Op_StrEquals: 559 case Op_StrIndexOf: 560 case Op_EncodeISOArray: { 561 add_local_var(n, PointsToNode::ArgEscape); 562 delayed_worklist->push(n); // Process it later. 563 break; 564 } 565 case Op_ThreadLocal: { 566 add_java_object(n, PointsToNode::ArgEscape); 567 break; 568 } 569 default: 570 ; // Do nothing for nodes not related to EA. 571 } 572 return; 573 } 574 575 #ifdef ASSERT 576 #define ELSE_FAIL(name) \ 577 /* Should not be called for not pointer type. */ \ 578 n->dump(1); \ 579 assert(false, name); \ 580 break; 581 #else 582 #define ELSE_FAIL(name) \ 583 break; 584 #endif 585 586 // Add final simple edges to graph. 587 void ConnectionGraph::add_final_edges(Node *n) { 588 PointsToNode* n_ptn = ptnode_adr(n->_idx); 589 #ifdef ASSERT 590 if (_verify && n_ptn->is_JavaObject()) 591 return; // This method does not change graph for JavaObject. 592 #endif 593 594 if (n->is_Call()) { 595 process_call_arguments(n->as_Call()); 596 return; 597 } 598 assert(n->is_Store() || n->is_LoadStore() || 599 (n_ptn != NULL) && (n_ptn->ideal_node() != NULL), 600 "node should be registered already"); 601 int opcode = n->Opcode(); 602 switch (opcode) { 603 case Op_AddP: { 604 Node* base = get_addp_base(n); 605 PointsToNode* ptn_base = ptnode_adr(base->_idx); 606 assert(ptn_base != NULL, "field's base should be registered"); 607 add_base(n_ptn->as_Field(), ptn_base); 608 break; 609 } 610 case Op_CastPP: 611 case Op_CheckCastPP: 612 case Op_EncodeP: 613 case Op_DecodeN: 614 case Op_EncodePKlass: 615 case Op_DecodeNKlass: { 616 add_local_var_and_edge(n, PointsToNode::NoEscape, 617 n->in(1), NULL); 618 break; 619 } 620 case Op_CMoveP: { 621 for (uint i = CMoveNode::IfFalse; i < n->req(); i++) { 622 Node* in = n->in(i); 623 if (in == NULL) 624 continue; // ignore NULL 625 Node* uncast_in = in->uncast(); 626 if (uncast_in->is_top() || uncast_in == n) 627 continue; // ignore top or inputs which go back this node 628 PointsToNode* ptn = ptnode_adr(in->_idx); 629 assert(ptn != NULL, "node should be registered"); 630 add_edge(n_ptn, ptn); 631 } 632 break; 633 } 634 case Op_LoadP: 635 case Op_LoadN: 636 case Op_LoadPLocked: { 637 // Using isa_ptr() instead of isa_oopptr() for LoadP and Phi because 638 // ThreadLocal has RawPtr type. 639 const Type* t = _igvn->type(n); 640 if (t->make_ptr() != NULL) { 641 Node* adr = n->in(MemNode::Address); 642 add_local_var_and_edge(n, PointsToNode::NoEscape, adr, NULL); 643 break; 644 } 645 ELSE_FAIL("Op_LoadP"); 646 } 647 case Op_Phi: { 648 // Using isa_ptr() instead of isa_oopptr() for LoadP and Phi because 649 // ThreadLocal has RawPtr type. 650 const Type* t = n->as_Phi()->type(); 651 if (t->make_ptr() != NULL) { 652 for (uint i = 1; i < n->req(); i++) { 653 Node* in = n->in(i); 654 if (in == NULL) 655 continue; // ignore NULL 656 Node* uncast_in = in->uncast(); 657 if (uncast_in->is_top() || uncast_in == n) 658 continue; // ignore top or inputs which go back this node 659 PointsToNode* ptn = ptnode_adr(in->_idx); 660 assert(ptn != NULL, "node should be registered"); 661 add_edge(n_ptn, ptn); 662 } 663 break; 664 } 665 ELSE_FAIL("Op_Phi"); 666 } 667 case Op_Proj: { 668 // we are only interested in the oop result projection from a call 669 if (n->as_Proj()->_con == TypeFunc::Parms && n->in(0)->is_Call() && 670 n->in(0)->as_Call()->returns_pointer()) { 671 add_local_var_and_edge(n, PointsToNode::NoEscape, n->in(0), NULL); 672 break; 673 } 674 ELSE_FAIL("Op_Proj"); 675 } 676 case Op_Rethrow: // Exception object escapes 677 case Op_Return: { 678 if (n->req() > TypeFunc::Parms && 679 _igvn->type(n->in(TypeFunc::Parms))->isa_oopptr()) { 680 // Treat Return value as LocalVar with GlobalEscape escape state. 681 add_local_var_and_edge(n, PointsToNode::GlobalEscape, 682 n->in(TypeFunc::Parms), NULL); 683 break; 684 } 685 ELSE_FAIL("Op_Return"); 686 } 687 case Op_StoreP: 688 case Op_StoreN: 689 case Op_StoreNKlass: 690 case Op_StorePConditional: 691 case Op_CompareAndSwapP: 692 case Op_CompareAndSwapN: 693 case Op_GetAndSetP: 694 case Op_GetAndSetN: { 695 Node* adr = n->in(MemNode::Address); 696 const Type *adr_type = _igvn->type(adr); 697 adr_type = adr_type->make_ptr(); 698 #ifdef ASSERT 699 if (adr_type == NULL) { 700 n->dump(1); 701 assert(adr_type != NULL, "dead node should not be on list"); 702 break; 703 } 704 #endif 705 if (opcode == Op_GetAndSetP || opcode == Op_GetAndSetN) { 706 add_local_var_and_edge(n, PointsToNode::NoEscape, adr, NULL); 707 } 708 if (adr_type->isa_oopptr() || 709 (opcode == Op_StoreP || opcode == Op_StoreN || opcode == Op_StoreNKlass) && 710 (adr_type == TypeRawPtr::NOTNULL && 711 adr->in(AddPNode::Address)->is_Proj() && 712 adr->in(AddPNode::Address)->in(0)->is_Allocate())) { 713 // Point Address to Value 714 PointsToNode* adr_ptn = ptnode_adr(adr->_idx); 715 assert(adr_ptn != NULL && 716 adr_ptn->as_Field()->is_oop(), "node should be registered"); 717 Node *val = n->in(MemNode::ValueIn); 718 PointsToNode* ptn = ptnode_adr(val->_idx); 719 assert(ptn != NULL, "node should be registered"); 720 add_edge(adr_ptn, ptn); 721 break; 722 } else if ((opcode == Op_StoreP) && (adr_type == TypeRawPtr::BOTTOM)) { 723 // Stored value escapes in unsafe access. 724 Node *val = n->in(MemNode::ValueIn); 725 PointsToNode* ptn = ptnode_adr(val->_idx); 726 assert(ptn != NULL, "node should be registered"); 727 set_escape_state(ptn, PointsToNode::GlobalEscape); 728 // Add edge to object for unsafe access with offset. 729 PointsToNode* adr_ptn = ptnode_adr(adr->_idx); 730 assert(adr_ptn != NULL, "node should be registered"); 731 if (adr_ptn->is_Field()) { 732 assert(adr_ptn->as_Field()->is_oop(), "should be oop field"); 733 add_edge(adr_ptn, ptn); 734 } 735 break; 736 } 737 ELSE_FAIL("Op_StoreP"); 738 } 739 case Op_AryEq: 740 case Op_StrComp: 741 case Op_StrEquals: 742 case Op_StrIndexOf: 743 case Op_EncodeISOArray: { 744 // char[] arrays passed to string intrinsic do not escape but 745 // they are not scalar replaceable. Adjust escape state for them. 746 // Start from in(2) edge since in(1) is memory edge. 747 for (uint i = 2; i < n->req(); i++) { 748 Node* adr = n->in(i); 749 const Type* at = _igvn->type(adr); 750 if (!adr->is_top() && at->isa_ptr()) { 751 assert(at == Type::TOP || at == TypePtr::NULL_PTR || 752 at->isa_ptr() != NULL, "expecting a pointer"); 753 if (adr->is_AddP()) { 754 adr = get_addp_base(adr); 755 } 756 PointsToNode* ptn = ptnode_adr(adr->_idx); 757 assert(ptn != NULL, "node should be registered"); 758 add_edge(n_ptn, ptn); 759 } 760 } 761 break; 762 } 763 default: { 764 // This method should be called only for EA specific nodes which may 765 // miss some edges when they were created. 766 #ifdef ASSERT 767 n->dump(1); 768 #endif 769 guarantee(false, "unknown node"); 770 } 771 } 772 return; 773 } 774 775 void ConnectionGraph::add_call_node(CallNode* call) { 776 assert(call->returns_pointer(), "only for call which returns pointer"); 777 uint call_idx = call->_idx; 778 if (call->is_Allocate()) { 779 Node* k = call->in(AllocateNode::KlassNode); 780 const TypeKlassPtr* kt = k->bottom_type()->isa_klassptr(); 781 assert(kt != NULL, "TypeKlassPtr required."); 782 ciKlass* cik = kt->klass(); 783 PointsToNode::EscapeState es = PointsToNode::NoEscape; 784 bool scalar_replaceable = true; 785 if (call->is_AllocateArray()) { 786 if (!cik->is_array_klass()) { // StressReflectiveCode 787 es = PointsToNode::GlobalEscape; 788 } else { 789 int length = call->in(AllocateNode::ALength)->find_int_con(-1); 790 if (length < 0 || length > EliminateAllocationArraySizeLimit) { 791 // Not scalar replaceable if the length is not constant or too big. 792 scalar_replaceable = false; 793 } 794 } 795 } else { // Allocate instance 796 if (cik->is_subclass_of(_compile->env()->Thread_klass()) || 797 cik->is_subclass_of(_compile->env()->Reference_klass()) || 798 !cik->is_instance_klass() || // StressReflectiveCode 799 cik->as_instance_klass()->has_finalizer()) { 800 es = PointsToNode::GlobalEscape; 801 } 802 } 803 add_java_object(call, es); 804 PointsToNode* ptn = ptnode_adr(call_idx); 805 if (!scalar_replaceable && ptn->scalar_replaceable()) { 806 ptn->set_scalar_replaceable(false); 807 } 808 } else if (call->is_CallStaticJava()) { 809 // Call nodes could be different types: 810 // 811 // 1. CallDynamicJavaNode (what happened during call is unknown): 812 // 813 // - mapped to GlobalEscape JavaObject node if oop is returned; 814 // 815 // - all oop arguments are escaping globally; 816 // 817 // 2. CallStaticJavaNode (execute bytecode analysis if possible): 818 // 819 // - the same as CallDynamicJavaNode if can't do bytecode analysis; 820 // 821 // - mapped to GlobalEscape JavaObject node if unknown oop is returned; 822 // - mapped to NoEscape JavaObject node if non-escaping object allocated 823 // during call is returned; 824 // - mapped to ArgEscape LocalVar node pointed to object arguments 825 // which are returned and does not escape during call; 826 // 827 // - oop arguments escaping status is defined by bytecode analysis; 828 // 829 // For a static call, we know exactly what method is being called. 830 // Use bytecode estimator to record whether the call's return value escapes. 831 ciMethod* meth = call->as_CallJava()->method(); 832 if (meth == NULL) { 833 const char* name = call->as_CallStaticJava()->_name; 834 assert(strncmp(name, "_multianewarray", 15) == 0, "TODO: add failed case check"); 835 // Returns a newly allocated unescaped object. 836 add_java_object(call, PointsToNode::NoEscape); 837 ptnode_adr(call_idx)->set_scalar_replaceable(false); 838 } else if (meth->is_boxing_method()) { 839 // Returns boxing object 840 PointsToNode::EscapeState es; 841 vmIntrinsics::ID intr = meth->intrinsic_id(); 842 if (intr == vmIntrinsics::_floatValue || intr == vmIntrinsics::_doubleValue) { 843 // It does not escape if object is always allocated. 844 es = PointsToNode::NoEscape; 845 } else { 846 // It escapes globally if object could be loaded from cache. 847 es = PointsToNode::GlobalEscape; 848 } 849 add_java_object(call, es); 850 } else { 851 BCEscapeAnalyzer* call_analyzer = meth->get_bcea(); 852 call_analyzer->copy_dependencies(_compile->dependencies()); 853 if (call_analyzer->is_return_allocated()) { 854 // Returns a newly allocated unescaped object, simply 855 // update dependency information. 856 // Mark it as NoEscape so that objects referenced by 857 // it's fields will be marked as NoEscape at least. 858 add_java_object(call, PointsToNode::NoEscape); 859 ptnode_adr(call_idx)->set_scalar_replaceable(false); 860 } else { 861 // Determine whether any arguments are returned. 862 const TypeTuple* d = call->tf()->domain(); 863 bool ret_arg = false; 864 for (uint i = TypeFunc::Parms; i < d->cnt(); i++) { 865 if (d->field_at(i)->isa_ptr() != NULL && 866 call_analyzer->is_arg_returned(i - TypeFunc::Parms)) { 867 ret_arg = true; 868 break; 869 } 870 } 871 if (ret_arg) { 872 add_local_var(call, PointsToNode::ArgEscape); 873 } else { 874 // Returns unknown object. 875 map_ideal_node(call, phantom_obj); 876 } 877 } 878 } 879 } else { 880 // An other type of call, assume the worst case: 881 // returned value is unknown and globally escapes. 882 assert(call->Opcode() == Op_CallDynamicJava, "add failed case check"); 883 map_ideal_node(call, phantom_obj); 884 } 885 } 886 887 void ConnectionGraph::process_call_arguments(CallNode *call) { 888 bool is_arraycopy = false; 889 switch (call->Opcode()) { 890 #ifdef ASSERT 891 case Op_Allocate: 892 case Op_AllocateArray: 893 case Op_Lock: 894 case Op_Unlock: 895 assert(false, "should be done already"); 896 break; 897 #endif 898 case Op_ArrayCopy: 899 case Op_CallLeafNoFP: 900 // Most array copies are ArrayCopy nodes at this point but there 901 // are still a few direct calls to the copy subroutines (See 902 // PhaseStringOpts::copy_string()) 903 is_arraycopy = (call->Opcode() == Op_ArrayCopy) || 904 (call->as_CallLeaf()->_name != NULL && 905 strstr(call->as_CallLeaf()->_name, "arraycopy") != 0); 906 // fall through 907 case Op_CallLeaf: { 908 // Stub calls, objects do not escape but they are not scale replaceable. 909 // Adjust escape state for outgoing arguments. 910 const TypeTuple * d = call->tf()->domain(); 911 bool src_has_oops = false; 912 for (uint i = TypeFunc::Parms; i < d->cnt(); i++) { 913 const Type* at = d->field_at(i); 914 Node *arg = call->in(i); 915 if (arg == NULL) { 916 continue; 917 } 918 const Type *aat = _igvn->type(arg); 919 if (arg->is_top() || !at->isa_ptr() || !aat->isa_ptr()) 920 continue; 921 if (arg->is_AddP()) { 922 // 923 // The inline_native_clone() case when the arraycopy stub is called 924 // after the allocation before Initialize and CheckCastPP nodes. 925 // Or normal arraycopy for object arrays case. 926 // 927 // Set AddP's base (Allocate) as not scalar replaceable since 928 // pointer to the base (with offset) is passed as argument. 929 // 930 arg = get_addp_base(arg); 931 } 932 PointsToNode* arg_ptn = ptnode_adr(arg->_idx); 933 assert(arg_ptn != NULL, "should be registered"); 934 PointsToNode::EscapeState arg_esc = arg_ptn->escape_state(); 935 if (is_arraycopy || arg_esc < PointsToNode::ArgEscape) { 936 assert(aat == Type::TOP || aat == TypePtr::NULL_PTR || 937 aat->isa_ptr() != NULL, "expecting an Ptr"); 938 bool arg_has_oops = aat->isa_oopptr() && 939 (aat->isa_oopptr()->klass() == NULL || aat->isa_instptr() || 940 (aat->isa_aryptr() && aat->isa_aryptr()->klass()->is_obj_array_klass())); 941 if (i == TypeFunc::Parms) { 942 src_has_oops = arg_has_oops; 943 } 944 // 945 // src or dst could be j.l.Object when other is basic type array: 946 // 947 // arraycopy(char[],0,Object*,0,size); 948 // arraycopy(Object*,0,char[],0,size); 949 // 950 // Don't add edges in such cases. 951 // 952 bool arg_is_arraycopy_dest = src_has_oops && is_arraycopy && 953 arg_has_oops && (i > TypeFunc::Parms); 954 #ifdef ASSERT 955 if (!(is_arraycopy || 956 (call->as_CallLeaf()->_name != NULL && 957 (strcmp(call->as_CallLeaf()->_name, "g1_wb_pre") == 0 || 958 strcmp(call->as_CallLeaf()->_name, "g1_wb_post") == 0 || 959 strcmp(call->as_CallLeaf()->_name, "updateBytesCRC32") == 0 || 960 strcmp(call->as_CallLeaf()->_name, "aescrypt_encryptBlock") == 0 || 961 strcmp(call->as_CallLeaf()->_name, "aescrypt_decryptBlock") == 0 || 962 strcmp(call->as_CallLeaf()->_name, "cipherBlockChaining_encryptAESCrypt") == 0 || 963 strcmp(call->as_CallLeaf()->_name, "cipherBlockChaining_decryptAESCrypt") == 0 || 964 strcmp(call->as_CallLeaf()->_name, "sha1_implCompress") == 0 || 965 strcmp(call->as_CallLeaf()->_name, "sha1_implCompressMB") == 0 || 966 strcmp(call->as_CallLeaf()->_name, "sha256_implCompress") == 0 || 967 strcmp(call->as_CallLeaf()->_name, "sha256_implCompressMB") == 0 || 968 strcmp(call->as_CallLeaf()->_name, "sha512_implCompress") == 0 || 969 strcmp(call->as_CallLeaf()->_name, "sha512_implCompressMB") == 0 || 970 strcmp(call->as_CallLeaf()->_name, "multiplyToLen") == 0) 971 ))) { 972 call->dump(); 973 fatal(err_msg_res("EA unexpected CallLeaf %s", call->as_CallLeaf()->_name)); 974 } 975 #endif 976 // Always process arraycopy's destination object since 977 // we need to add all possible edges to references in 978 // source object. 979 if (arg_esc >= PointsToNode::ArgEscape && 980 !arg_is_arraycopy_dest) { 981 continue; 982 } 983 set_escape_state(arg_ptn, PointsToNode::ArgEscape); 984 if (arg_is_arraycopy_dest) { 985 Node* src = call->in(TypeFunc::Parms); 986 if (src->is_AddP()) { 987 src = get_addp_base(src); 988 } 989 PointsToNode* src_ptn = ptnode_adr(src->_idx); 990 assert(src_ptn != NULL, "should be registered"); 991 if (arg_ptn != src_ptn) { 992 // Special arraycopy edge: 993 // A destination object's field can't have the source object 994 // as base since objects escape states are not related. 995 // Only escape state of destination object's fields affects 996 // escape state of fields in source object. 997 add_arraycopy(call, PointsToNode::ArgEscape, src_ptn, arg_ptn); 998 } 999 } 1000 } 1001 } 1002 break; 1003 } 1004 case Op_CallStaticJava: { 1005 // For a static call, we know exactly what method is being called. 1006 // Use bytecode estimator to record the call's escape affects 1007 #ifdef ASSERT 1008 const char* name = call->as_CallStaticJava()->_name; 1009 assert((name == NULL || strcmp(name, "uncommon_trap") != 0), "normal calls only"); 1010 #endif 1011 ciMethod* meth = call->as_CallJava()->method(); 1012 if ((meth != NULL) && meth->is_boxing_method()) { 1013 break; // Boxing methods do not modify any oops. 1014 } 1015 BCEscapeAnalyzer* call_analyzer = (meth !=NULL) ? meth->get_bcea() : NULL; 1016 // fall-through if not a Java method or no analyzer information 1017 if (call_analyzer != NULL) { 1018 PointsToNode* call_ptn = ptnode_adr(call->_idx); 1019 const TypeTuple* d = call->tf()->domain(); 1020 for (uint i = TypeFunc::Parms; i < d->cnt(); i++) { 1021 const Type* at = d->field_at(i); 1022 int k = i - TypeFunc::Parms; 1023 Node* arg = call->in(i); 1024 PointsToNode* arg_ptn = ptnode_adr(arg->_idx); 1025 if (at->isa_ptr() != NULL && 1026 call_analyzer->is_arg_returned(k)) { 1027 // The call returns arguments. 1028 if (call_ptn != NULL) { // Is call's result used? 1029 assert(call_ptn->is_LocalVar(), "node should be registered"); 1030 assert(arg_ptn != NULL, "node should be registered"); 1031 add_edge(call_ptn, arg_ptn); 1032 } 1033 } 1034 if (at->isa_oopptr() != NULL && 1035 arg_ptn->escape_state() < PointsToNode::GlobalEscape) { 1036 if (!call_analyzer->is_arg_stack(k)) { 1037 // The argument global escapes 1038 set_escape_state(arg_ptn, PointsToNode::GlobalEscape); 1039 } else { 1040 set_escape_state(arg_ptn, PointsToNode::ArgEscape); 1041 if (!call_analyzer->is_arg_local(k)) { 1042 // The argument itself doesn't escape, but any fields might 1043 set_fields_escape_state(arg_ptn, PointsToNode::GlobalEscape); 1044 } 1045 } 1046 } 1047 } 1048 if (call_ptn != NULL && call_ptn->is_LocalVar()) { 1049 // The call returns arguments. 1050 assert(call_ptn->edge_count() > 0, "sanity"); 1051 if (!call_analyzer->is_return_local()) { 1052 // Returns also unknown object. 1053 add_edge(call_ptn, phantom_obj); 1054 } 1055 } 1056 break; 1057 } 1058 } 1059 default: { 1060 // Fall-through here if not a Java method or no analyzer information 1061 // or some other type of call, assume the worst case: all arguments 1062 // globally escape. 1063 const TypeTuple* d = call->tf()->domain(); 1064 for (uint i = TypeFunc::Parms; i < d->cnt(); i++) { 1065 const Type* at = d->field_at(i); 1066 if (at->isa_oopptr() != NULL) { 1067 Node* arg = call->in(i); 1068 if (arg->is_AddP()) { 1069 arg = get_addp_base(arg); 1070 } 1071 assert(ptnode_adr(arg->_idx) != NULL, "should be defined already"); 1072 set_escape_state(ptnode_adr(arg->_idx), PointsToNode::GlobalEscape); 1073 } 1074 } 1075 } 1076 } 1077 } 1078 1079 1080 // Finish Graph construction. 1081 bool ConnectionGraph::complete_connection_graph( 1082 GrowableArray<PointsToNode*>& ptnodes_worklist, 1083 GrowableArray<JavaObjectNode*>& non_escaped_worklist, 1084 GrowableArray<JavaObjectNode*>& java_objects_worklist, 1085 GrowableArray<FieldNode*>& oop_fields_worklist) { 1086 // Normally only 1-3 passes needed to build Connection Graph depending 1087 // on graph complexity. Observed 8 passes in jvm2008 compiler.compiler. 1088 // Set limit to 20 to catch situation when something did go wrong and 1089 // bailout Escape Analysis. 1090 // Also limit build time to 20 sec (60 in debug VM), EscapeAnalysisTimeout flag. 1091 #define CG_BUILD_ITER_LIMIT 20 1092 1093 // Propagate GlobalEscape and ArgEscape escape states and check that 1094 // we still have non-escaping objects. The method pushs on _worklist 1095 // Field nodes which reference phantom_object. 1096 if (!find_non_escaped_objects(ptnodes_worklist, non_escaped_worklist)) { 1097 return false; // Nothing to do. 1098 } 1099 // Now propagate references to all JavaObject nodes. 1100 int java_objects_length = java_objects_worklist.length(); 1101 elapsedTimer time; 1102 bool timeout = false; 1103 int new_edges = 1; 1104 int iterations = 0; 1105 do { 1106 while ((new_edges > 0) && 1107 (iterations++ < CG_BUILD_ITER_LIMIT)) { 1108 double start_time = time.seconds(); 1109 time.start(); 1110 new_edges = 0; 1111 // Propagate references to phantom_object for nodes pushed on _worklist 1112 // by find_non_escaped_objects() and find_field_value(). 1113 new_edges += add_java_object_edges(phantom_obj, false); 1114 for (int next = 0; next < java_objects_length; ++next) { 1115 JavaObjectNode* ptn = java_objects_worklist.at(next); 1116 new_edges += add_java_object_edges(ptn, true); 1117 1118 #define SAMPLE_SIZE 4 1119 if ((next % SAMPLE_SIZE) == 0) { 1120 // Each 4 iterations calculate how much time it will take 1121 // to complete graph construction. 1122 time.stop(); 1123 // Poll for requests from shutdown mechanism to quiesce compiler 1124 // because Connection graph construction may take long time. 1125 CompileBroker::maybe_block(); 1126 double stop_time = time.seconds(); 1127 double time_per_iter = (stop_time - start_time) / (double)SAMPLE_SIZE; 1128 double time_until_end = time_per_iter * (double)(java_objects_length - next); 1129 if ((start_time + time_until_end) >= EscapeAnalysisTimeout) { 1130 timeout = true; 1131 break; // Timeout 1132 } 1133 start_time = stop_time; 1134 time.start(); 1135 } 1136 #undef SAMPLE_SIZE 1137 1138 } 1139 if (timeout) break; 1140 if (new_edges > 0) { 1141 // Update escape states on each iteration if graph was updated. 1142 if (!find_non_escaped_objects(ptnodes_worklist, non_escaped_worklist)) { 1143 return false; // Nothing to do. 1144 } 1145 } 1146 time.stop(); 1147 if (time.seconds() >= EscapeAnalysisTimeout) { 1148 timeout = true; 1149 break; 1150 } 1151 } 1152 if ((iterations < CG_BUILD_ITER_LIMIT) && !timeout) { 1153 time.start(); 1154 // Find fields which have unknown value. 1155 int fields_length = oop_fields_worklist.length(); 1156 for (int next = 0; next < fields_length; next++) { 1157 FieldNode* field = oop_fields_worklist.at(next); 1158 if (field->edge_count() == 0) { 1159 new_edges += find_field_value(field); 1160 // This code may added new edges to phantom_object. 1161 // Need an other cycle to propagate references to phantom_object. 1162 } 1163 } 1164 time.stop(); 1165 if (time.seconds() >= EscapeAnalysisTimeout) { 1166 timeout = true; 1167 break; 1168 } 1169 } else { 1170 new_edges = 0; // Bailout 1171 } 1172 } while (new_edges > 0); 1173 1174 // Bailout if passed limits. 1175 if ((iterations >= CG_BUILD_ITER_LIMIT) || timeout) { 1176 Compile* C = _compile; 1177 if (C->log() != NULL) { 1178 C->log()->begin_elem("connectionGraph_bailout reason='reached "); 1179 C->log()->text("%s", timeout ? "time" : "iterations"); 1180 C->log()->end_elem(" limit'"); 1181 } 1182 assert(ExitEscapeAnalysisOnTimeout, err_msg_res("infinite EA connection graph build (%f sec, %d iterations) with %d nodes and worklist size %d", 1183 time.seconds(), iterations, nodes_size(), ptnodes_worklist.length())); 1184 // Possible infinite build_connection_graph loop, 1185 // bailout (no changes to ideal graph were made). 1186 return false; 1187 } 1188 #ifdef ASSERT 1189 if (Verbose && PrintEscapeAnalysis) { 1190 tty->print_cr("EA: %d iterations to build connection graph with %d nodes and worklist size %d", 1191 iterations, nodes_size(), ptnodes_worklist.length()); 1192 } 1193 #endif 1194 1195 #undef CG_BUILD_ITER_LIMIT 1196 1197 // Find fields initialized by NULL for non-escaping Allocations. 1198 int non_escaped_length = non_escaped_worklist.length(); 1199 for (int next = 0; next < non_escaped_length; next++) { 1200 JavaObjectNode* ptn = non_escaped_worklist.at(next); 1201 PointsToNode::EscapeState es = ptn->escape_state(); 1202 assert(es <= PointsToNode::ArgEscape, "sanity"); 1203 if (es == PointsToNode::NoEscape) { 1204 if (find_init_values(ptn, null_obj, _igvn) > 0) { 1205 // Adding references to NULL object does not change escape states 1206 // since it does not escape. Also no fields are added to NULL object. 1207 add_java_object_edges(null_obj, false); 1208 } 1209 } 1210 Node* n = ptn->ideal_node(); 1211 if (n->is_Allocate()) { 1212 // The object allocated by this Allocate node will never be 1213 // seen by an other thread. Mark it so that when it is 1214 // expanded no MemBarStoreStore is added. 1215 InitializeNode* ini = n->as_Allocate()->initialization(); 1216 if (ini != NULL) 1217 ini->set_does_not_escape(); 1218 } 1219 } 1220 return true; // Finished graph construction. 1221 } 1222 1223 // Propagate GlobalEscape and ArgEscape escape states to all nodes 1224 // and check that we still have non-escaping java objects. 1225 bool ConnectionGraph::find_non_escaped_objects(GrowableArray<PointsToNode*>& ptnodes_worklist, 1226 GrowableArray<JavaObjectNode*>& non_escaped_worklist) { 1227 GrowableArray<PointsToNode*> escape_worklist; 1228 // First, put all nodes with GlobalEscape and ArgEscape states on worklist. 1229 int ptnodes_length = ptnodes_worklist.length(); 1230 for (int next = 0; next < ptnodes_length; ++next) { 1231 PointsToNode* ptn = ptnodes_worklist.at(next); 1232 if (ptn->escape_state() >= PointsToNode::ArgEscape || 1233 ptn->fields_escape_state() >= PointsToNode::ArgEscape) { 1234 escape_worklist.push(ptn); 1235 } 1236 } 1237 // Set escape states to referenced nodes (edges list). 1238 while (escape_worklist.length() > 0) { 1239 PointsToNode* ptn = escape_worklist.pop(); 1240 PointsToNode::EscapeState es = ptn->escape_state(); 1241 PointsToNode::EscapeState field_es = ptn->fields_escape_state(); 1242 if (ptn->is_Field() && ptn->as_Field()->is_oop() && 1243 es >= PointsToNode::ArgEscape) { 1244 // GlobalEscape or ArgEscape state of field means it has unknown value. 1245 if (add_edge(ptn, phantom_obj)) { 1246 // New edge was added 1247 add_field_uses_to_worklist(ptn->as_Field()); 1248 } 1249 } 1250 for (EdgeIterator i(ptn); i.has_next(); i.next()) { 1251 PointsToNode* e = i.get(); 1252 if (e->is_Arraycopy()) { 1253 assert(ptn->arraycopy_dst(), "sanity"); 1254 // Propagate only fields escape state through arraycopy edge. 1255 if (e->fields_escape_state() < field_es) { 1256 set_fields_escape_state(e, field_es); 1257 escape_worklist.push(e); 1258 } 1259 } else if (es >= field_es) { 1260 // fields_escape_state is also set to 'es' if it is less than 'es'. 1261 if (e->escape_state() < es) { 1262 set_escape_state(e, es); 1263 escape_worklist.push(e); 1264 } 1265 } else { 1266 // Propagate field escape state. 1267 bool es_changed = false; 1268 if (e->fields_escape_state() < field_es) { 1269 set_fields_escape_state(e, field_es); 1270 es_changed = true; 1271 } 1272 if ((e->escape_state() < field_es) && 1273 e->is_Field() && ptn->is_JavaObject() && 1274 e->as_Field()->is_oop()) { 1275 // Change escape state of referenced fileds. 1276 set_escape_state(e, field_es); 1277 es_changed = true;; 1278 } else if (e->escape_state() < es) { 1279 set_escape_state(e, es); 1280 es_changed = true;; 1281 } 1282 if (es_changed) { 1283 escape_worklist.push(e); 1284 } 1285 } 1286 } 1287 } 1288 // Remove escaped objects from non_escaped list. 1289 for (int next = non_escaped_worklist.length()-1; next >= 0 ; --next) { 1290 JavaObjectNode* ptn = non_escaped_worklist.at(next); 1291 if (ptn->escape_state() >= PointsToNode::GlobalEscape) { 1292 non_escaped_worklist.delete_at(next); 1293 } 1294 if (ptn->escape_state() == PointsToNode::NoEscape) { 1295 // Find fields in non-escaped allocations which have unknown value. 1296 find_init_values(ptn, phantom_obj, NULL); 1297 } 1298 } 1299 return (non_escaped_worklist.length() > 0); 1300 } 1301 1302 // Add all references to JavaObject node by walking over all uses. 1303 int ConnectionGraph::add_java_object_edges(JavaObjectNode* jobj, bool populate_worklist) { 1304 int new_edges = 0; 1305 if (populate_worklist) { 1306 // Populate _worklist by uses of jobj's uses. 1307 for (UseIterator i(jobj); i.has_next(); i.next()) { 1308 PointsToNode* use = i.get(); 1309 if (use->is_Arraycopy()) 1310 continue; 1311 add_uses_to_worklist(use); 1312 if (use->is_Field() && use->as_Field()->is_oop()) { 1313 // Put on worklist all field's uses (loads) and 1314 // related field nodes (same base and offset). 1315 add_field_uses_to_worklist(use->as_Field()); 1316 } 1317 } 1318 } 1319 for (int l = 0; l < _worklist.length(); l++) { 1320 PointsToNode* use = _worklist.at(l); 1321 if (PointsToNode::is_base_use(use)) { 1322 // Add reference from jobj to field and from field to jobj (field's base). 1323 use = PointsToNode::get_use_node(use)->as_Field(); 1324 if (add_base(use->as_Field(), jobj)) { 1325 new_edges++; 1326 } 1327 continue; 1328 } 1329 assert(!use->is_JavaObject(), "sanity"); 1330 if (use->is_Arraycopy()) { 1331 if (jobj == null_obj) // NULL object does not have field edges 1332 continue; 1333 // Added edge from Arraycopy node to arraycopy's source java object 1334 if (add_edge(use, jobj)) { 1335 jobj->set_arraycopy_src(); 1336 new_edges++; 1337 } 1338 // and stop here. 1339 continue; 1340 } 1341 if (!add_edge(use, jobj)) 1342 continue; // No new edge added, there was such edge already. 1343 new_edges++; 1344 if (use->is_LocalVar()) { 1345 add_uses_to_worklist(use); 1346 if (use->arraycopy_dst()) { 1347 for (EdgeIterator i(use); i.has_next(); i.next()) { 1348 PointsToNode* e = i.get(); 1349 if (e->is_Arraycopy()) { 1350 if (jobj == null_obj) // NULL object does not have field edges 1351 continue; 1352 // Add edge from arraycopy's destination java object to Arraycopy node. 1353 if (add_edge(jobj, e)) { 1354 new_edges++; 1355 jobj->set_arraycopy_dst(); 1356 } 1357 } 1358 } 1359 } 1360 } else { 1361 // Added new edge to stored in field values. 1362 // Put on worklist all field's uses (loads) and 1363 // related field nodes (same base and offset). 1364 add_field_uses_to_worklist(use->as_Field()); 1365 } 1366 } 1367 _worklist.clear(); 1368 _in_worklist.Reset(); 1369 return new_edges; 1370 } 1371 1372 // Put on worklist all related field nodes. 1373 void ConnectionGraph::add_field_uses_to_worklist(FieldNode* field) { 1374 assert(field->is_oop(), "sanity"); 1375 int offset = field->offset(); 1376 add_uses_to_worklist(field); 1377 // Loop over all bases of this field and push on worklist Field nodes 1378 // with the same offset and base (since they may reference the same field). 1379 for (BaseIterator i(field); i.has_next(); i.next()) { 1380 PointsToNode* base = i.get(); 1381 add_fields_to_worklist(field, base); 1382 // Check if the base was source object of arraycopy and go over arraycopy's 1383 // destination objects since values stored to a field of source object are 1384 // accessable by uses (loads) of fields of destination objects. 1385 if (base->arraycopy_src()) { 1386 for (UseIterator j(base); j.has_next(); j.next()) { 1387 PointsToNode* arycp = j.get(); 1388 if (arycp->is_Arraycopy()) { 1389 for (UseIterator k(arycp); k.has_next(); k.next()) { 1390 PointsToNode* abase = k.get(); 1391 if (abase->arraycopy_dst() && abase != base) { 1392 // Look for the same arracopy reference. 1393 add_fields_to_worklist(field, abase); 1394 } 1395 } 1396 } 1397 } 1398 } 1399 } 1400 } 1401 1402 // Put on worklist all related field nodes. 1403 void ConnectionGraph::add_fields_to_worklist(FieldNode* field, PointsToNode* base) { 1404 int offset = field->offset(); 1405 if (base->is_LocalVar()) { 1406 for (UseIterator j(base); j.has_next(); j.next()) { 1407 PointsToNode* f = j.get(); 1408 if (PointsToNode::is_base_use(f)) { // Field 1409 f = PointsToNode::get_use_node(f); 1410 if (f == field || !f->as_Field()->is_oop()) 1411 continue; 1412 int offs = f->as_Field()->offset(); 1413 if (offs == offset || offset == Type::OffsetBot || offs == Type::OffsetBot) { 1414 add_to_worklist(f); 1415 } 1416 } 1417 } 1418 } else { 1419 assert(base->is_JavaObject(), "sanity"); 1420 if (// Skip phantom_object since it is only used to indicate that 1421 // this field's content globally escapes. 1422 (base != phantom_obj) && 1423 // NULL object node does not have fields. 1424 (base != null_obj)) { 1425 for (EdgeIterator i(base); i.has_next(); i.next()) { 1426 PointsToNode* f = i.get(); 1427 // Skip arraycopy edge since store to destination object field 1428 // does not update value in source object field. 1429 if (f->is_Arraycopy()) { 1430 assert(base->arraycopy_dst(), "sanity"); 1431 continue; 1432 } 1433 if (f == field || !f->as_Field()->is_oop()) 1434 continue; 1435 int offs = f->as_Field()->offset(); 1436 if (offs == offset || offset == Type::OffsetBot || offs == Type::OffsetBot) { 1437 add_to_worklist(f); 1438 } 1439 } 1440 } 1441 } 1442 } 1443 1444 // Find fields which have unknown value. 1445 int ConnectionGraph::find_field_value(FieldNode* field) { 1446 // Escaped fields should have init value already. 1447 assert(field->escape_state() == PointsToNode::NoEscape, "sanity"); 1448 int new_edges = 0; 1449 for (BaseIterator i(field); i.has_next(); i.next()) { 1450 PointsToNode* base = i.get(); 1451 if (base->is_JavaObject()) { 1452 // Skip Allocate's fields which will be processed later. 1453 if (base->ideal_node()->is_Allocate()) 1454 return 0; 1455 assert(base == null_obj, "only NULL ptr base expected here"); 1456 } 1457 } 1458 if (add_edge(field, phantom_obj)) { 1459 // New edge was added 1460 new_edges++; 1461 add_field_uses_to_worklist(field); 1462 } 1463 return new_edges; 1464 } 1465 1466 // Find fields initializing values for allocations. 1467 int ConnectionGraph::find_init_values(JavaObjectNode* pta, PointsToNode* init_val, PhaseTransform* phase) { 1468 assert(pta->escape_state() == PointsToNode::NoEscape, "Not escaped Allocate nodes only"); 1469 int new_edges = 0; 1470 Node* alloc = pta->ideal_node(); 1471 if (init_val == phantom_obj) { 1472 // Do nothing for Allocate nodes since its fields values are "known". 1473 if (alloc->is_Allocate()) 1474 return 0; 1475 assert(alloc->as_CallStaticJava(), "sanity"); 1476 #ifdef ASSERT 1477 if (alloc->as_CallStaticJava()->method() == NULL) { 1478 const char* name = alloc->as_CallStaticJava()->_name; 1479 assert(strncmp(name, "_multianewarray", 15) == 0, "sanity"); 1480 } 1481 #endif 1482 // Non-escaped allocation returned from Java or runtime call have 1483 // unknown values in fields. 1484 for (EdgeIterator i(pta); i.has_next(); i.next()) { 1485 PointsToNode* field = i.get(); 1486 if (field->is_Field() && field->as_Field()->is_oop()) { 1487 if (add_edge(field, phantom_obj)) { 1488 // New edge was added 1489 new_edges++; 1490 add_field_uses_to_worklist(field->as_Field()); 1491 } 1492 } 1493 } 1494 return new_edges; 1495 } 1496 assert(init_val == null_obj, "sanity"); 1497 // Do nothing for Call nodes since its fields values are unknown. 1498 if (!alloc->is_Allocate()) 1499 return 0; 1500 1501 InitializeNode* ini = alloc->as_Allocate()->initialization(); 1502 bool visited_bottom_offset = false; 1503 GrowableArray<int> offsets_worklist; 1504 1505 // Check if an oop field's initializing value is recorded and add 1506 // a corresponding NULL if field's value if it is not recorded. 1507 // Connection Graph does not record a default initialization by NULL 1508 // captured by Initialize node. 1509 // 1510 for (EdgeIterator i(pta); i.has_next(); i.next()) { 1511 PointsToNode* field = i.get(); // Field (AddP) 1512 if (!field->is_Field() || !field->as_Field()->is_oop()) 1513 continue; // Not oop field 1514 int offset = field->as_Field()->offset(); 1515 if (offset == Type::OffsetBot) { 1516 if (!visited_bottom_offset) { 1517 // OffsetBot is used to reference array's element, 1518 // always add reference to NULL to all Field nodes since we don't 1519 // known which element is referenced. 1520 if (add_edge(field, null_obj)) { 1521 // New edge was added 1522 new_edges++; 1523 add_field_uses_to_worklist(field->as_Field()); 1524 visited_bottom_offset = true; 1525 } 1526 } 1527 } else { 1528 // Check only oop fields. 1529 const Type* adr_type = field->ideal_node()->as_AddP()->bottom_type(); 1530 if (adr_type->isa_rawptr()) { 1531 #ifdef ASSERT 1532 // Raw pointers are used for initializing stores so skip it 1533 // since it should be recorded already 1534 Node* base = get_addp_base(field->ideal_node()); 1535 assert(adr_type->isa_rawptr() && base->is_Proj() && 1536 (base->in(0) == alloc),"unexpected pointer type"); 1537 #endif 1538 continue; 1539 } 1540 if (!offsets_worklist.contains(offset)) { 1541 offsets_worklist.append(offset); 1542 Node* value = NULL; 1543 if (ini != NULL) { 1544 // StoreP::memory_type() == T_ADDRESS 1545 BasicType ft = UseCompressedOops ? T_NARROWOOP : T_ADDRESS; 1546 Node* store = ini->find_captured_store(offset, type2aelembytes(ft, true), phase); 1547 // Make sure initializing store has the same type as this AddP. 1548 // This AddP may reference non existing field because it is on a 1549 // dead branch of bimorphic call which is not eliminated yet. 1550 if (store != NULL && store->is_Store() && 1551 store->as_Store()->memory_type() == ft) { 1552 value = store->in(MemNode::ValueIn); 1553 #ifdef ASSERT 1554 if (VerifyConnectionGraph) { 1555 // Verify that AddP already points to all objects the value points to. 1556 PointsToNode* val = ptnode_adr(value->_idx); 1557 assert((val != NULL), "should be processed already"); 1558 PointsToNode* missed_obj = NULL; 1559 if (val->is_JavaObject()) { 1560 if (!field->points_to(val->as_JavaObject())) { 1561 missed_obj = val; 1562 } 1563 } else { 1564 if (!val->is_LocalVar() || (val->edge_count() == 0)) { 1565 tty->print_cr("----------init store has invalid value -----"); 1566 store->dump(); 1567 val->dump(); 1568 assert(val->is_LocalVar() && (val->edge_count() > 0), "should be processed already"); 1569 } 1570 for (EdgeIterator j(val); j.has_next(); j.next()) { 1571 PointsToNode* obj = j.get(); 1572 if (obj->is_JavaObject()) { 1573 if (!field->points_to(obj->as_JavaObject())) { 1574 missed_obj = obj; 1575 break; 1576 } 1577 } 1578 } 1579 } 1580 if (missed_obj != NULL) { 1581 tty->print_cr("----------field---------------------------------"); 1582 field->dump(); 1583 tty->print_cr("----------missed referernce to object-----------"); 1584 missed_obj->dump(); 1585 tty->print_cr("----------object referernced by init store -----"); 1586 store->dump(); 1587 val->dump(); 1588 assert(!field->points_to(missed_obj->as_JavaObject()), "missed JavaObject reference"); 1589 } 1590 } 1591 #endif 1592 } else { 1593 // There could be initializing stores which follow allocation. 1594 // For example, a volatile field store is not collected 1595 // by Initialize node. 1596 // 1597 // Need to check for dependent loads to separate such stores from 1598 // stores which follow loads. For now, add initial value NULL so 1599 // that compare pointers optimization works correctly. 1600 } 1601 } 1602 if (value == NULL) { 1603 // A field's initializing value was not recorded. Add NULL. 1604 if (add_edge(field, null_obj)) { 1605 // New edge was added 1606 new_edges++; 1607 add_field_uses_to_worklist(field->as_Field()); 1608 } 1609 } 1610 } 1611 } 1612 } 1613 return new_edges; 1614 } 1615 1616 // Adjust scalar_replaceable state after Connection Graph is built. 1617 void ConnectionGraph::adjust_scalar_replaceable_state(JavaObjectNode* jobj) { 1618 // Search for non-escaping objects which are not scalar replaceable 1619 // and mark them to propagate the state to referenced objects. 1620 1621 // 1. An object is not scalar replaceable if the field into which it is 1622 // stored has unknown offset (stored into unknown element of an array). 1623 // 1624 for (UseIterator i(jobj); i.has_next(); i.next()) { 1625 PointsToNode* use = i.get(); 1626 assert(!use->is_Arraycopy(), "sanity"); 1627 if (use->is_Field()) { 1628 FieldNode* field = use->as_Field(); 1629 assert(field->is_oop() && field->scalar_replaceable() && 1630 field->fields_escape_state() == PointsToNode::NoEscape, "sanity"); 1631 if (field->offset() == Type::OffsetBot) { 1632 jobj->set_scalar_replaceable(false); 1633 return; 1634 } 1635 // 2. An object is not scalar replaceable if the field into which it is 1636 // stored has multiple bases one of which is null. 1637 if (field->base_count() > 1) { 1638 for (BaseIterator i(field); i.has_next(); i.next()) { 1639 PointsToNode* base = i.get(); 1640 if (base == null_obj) { 1641 jobj->set_scalar_replaceable(false); 1642 return; 1643 } 1644 } 1645 } 1646 } 1647 assert(use->is_Field() || use->is_LocalVar(), "sanity"); 1648 // 3. An object is not scalar replaceable if it is merged with other objects. 1649 for (EdgeIterator j(use); j.has_next(); j.next()) { 1650 PointsToNode* ptn = j.get(); 1651 if (ptn->is_JavaObject() && ptn != jobj) { 1652 // Mark all objects. 1653 jobj->set_scalar_replaceable(false); 1654 ptn->set_scalar_replaceable(false); 1655 } 1656 } 1657 if (!jobj->scalar_replaceable()) { 1658 return; 1659 } 1660 } 1661 1662 for (EdgeIterator j(jobj); j.has_next(); j.next()) { 1663 // Non-escaping object node should point only to field nodes. 1664 FieldNode* field = j.get()->as_Field(); 1665 int offset = field->as_Field()->offset(); 1666 1667 // 4. An object is not scalar replaceable if it has a field with unknown 1668 // offset (array's element is accessed in loop). 1669 if (offset == Type::OffsetBot) { 1670 jobj->set_scalar_replaceable(false); 1671 return; 1672 } 1673 // 5. Currently an object is not scalar replaceable if a LoadStore node 1674 // access its field since the field value is unknown after it. 1675 // 1676 Node* n = field->ideal_node(); 1677 for (DUIterator_Fast imax, i = n->fast_outs(imax); i < imax; i++) { 1678 if (n->fast_out(i)->is_LoadStore()) { 1679 jobj->set_scalar_replaceable(false); 1680 return; 1681 } 1682 } 1683 1684 // 6. Or the address may point to more then one object. This may produce 1685 // the false positive result (set not scalar replaceable) 1686 // since the flow-insensitive escape analysis can't separate 1687 // the case when stores overwrite the field's value from the case 1688 // when stores happened on different control branches. 1689 // 1690 // Note: it will disable scalar replacement in some cases: 1691 // 1692 // Point p[] = new Point[1]; 1693 // p[0] = new Point(); // Will be not scalar replaced 1694 // 1695 // but it will save us from incorrect optimizations in next cases: 1696 // 1697 // Point p[] = new Point[1]; 1698 // if ( x ) p[0] = new Point(); // Will be not scalar replaced 1699 // 1700 if (field->base_count() > 1) { 1701 for (BaseIterator i(field); i.has_next(); i.next()) { 1702 PointsToNode* base = i.get(); 1703 // Don't take into account LocalVar nodes which 1704 // may point to only one object which should be also 1705 // this field's base by now. 1706 if (base->is_JavaObject() && base != jobj) { 1707 // Mark all bases. 1708 jobj->set_scalar_replaceable(false); 1709 base->set_scalar_replaceable(false); 1710 } 1711 } 1712 } 1713 } 1714 } 1715 1716 #ifdef ASSERT 1717 void ConnectionGraph::verify_connection_graph( 1718 GrowableArray<PointsToNode*>& ptnodes_worklist, 1719 GrowableArray<JavaObjectNode*>& non_escaped_worklist, 1720 GrowableArray<JavaObjectNode*>& java_objects_worklist, 1721 GrowableArray<Node*>& addp_worklist) { 1722 // Verify that graph is complete - no new edges could be added. 1723 int java_objects_length = java_objects_worklist.length(); 1724 int non_escaped_length = non_escaped_worklist.length(); 1725 int new_edges = 0; 1726 for (int next = 0; next < java_objects_length; ++next) { 1727 JavaObjectNode* ptn = java_objects_worklist.at(next); 1728 new_edges += add_java_object_edges(ptn, true); 1729 } 1730 assert(new_edges == 0, "graph was not complete"); 1731 // Verify that escape state is final. 1732 int length = non_escaped_worklist.length(); 1733 find_non_escaped_objects(ptnodes_worklist, non_escaped_worklist); 1734 assert((non_escaped_length == non_escaped_worklist.length()) && 1735 (non_escaped_length == length) && 1736 (_worklist.length() == 0), "escape state was not final"); 1737 1738 // Verify fields information. 1739 int addp_length = addp_worklist.length(); 1740 for (int next = 0; next < addp_length; ++next ) { 1741 Node* n = addp_worklist.at(next); 1742 FieldNode* field = ptnode_adr(n->_idx)->as_Field(); 1743 if (field->is_oop()) { 1744 // Verify that field has all bases 1745 Node* base = get_addp_base(n); 1746 PointsToNode* ptn = ptnode_adr(base->_idx); 1747 if (ptn->is_JavaObject()) { 1748 assert(field->has_base(ptn->as_JavaObject()), "sanity"); 1749 } else { 1750 assert(ptn->is_LocalVar(), "sanity"); 1751 for (EdgeIterator i(ptn); i.has_next(); i.next()) { 1752 PointsToNode* e = i.get(); 1753 if (e->is_JavaObject()) { 1754 assert(field->has_base(e->as_JavaObject()), "sanity"); 1755 } 1756 } 1757 } 1758 // Verify that all fields have initializing values. 1759 if (field->edge_count() == 0) { 1760 tty->print_cr("----------field does not have references----------"); 1761 field->dump(); 1762 for (BaseIterator i(field); i.has_next(); i.next()) { 1763 PointsToNode* base = i.get(); 1764 tty->print_cr("----------field has next base---------------------"); 1765 base->dump(); 1766 if (base->is_JavaObject() && (base != phantom_obj) && (base != null_obj)) { 1767 tty->print_cr("----------base has fields-------------------------"); 1768 for (EdgeIterator j(base); j.has_next(); j.next()) { 1769 j.get()->dump(); 1770 } 1771 tty->print_cr("----------base has references---------------------"); 1772 for (UseIterator j(base); j.has_next(); j.next()) { 1773 j.get()->dump(); 1774 } 1775 } 1776 } 1777 for (UseIterator i(field); i.has_next(); i.next()) { 1778 i.get()->dump(); 1779 } 1780 assert(field->edge_count() > 0, "sanity"); 1781 } 1782 } 1783 } 1784 } 1785 #endif 1786 1787 // Optimize ideal graph. 1788 void ConnectionGraph::optimize_ideal_graph(GrowableArray<Node*>& ptr_cmp_worklist, 1789 GrowableArray<Node*>& storestore_worklist) { 1790 Compile* C = _compile; 1791 PhaseIterGVN* igvn = _igvn; 1792 if (EliminateLocks) { 1793 // Mark locks before changing ideal graph. 1794 int cnt = C->macro_count(); 1795 for( int i=0; i < cnt; i++ ) { 1796 Node *n = C->macro_node(i); 1797 if (n->is_AbstractLock()) { // Lock and Unlock nodes 1798 AbstractLockNode* alock = n->as_AbstractLock(); 1799 if (!alock->is_non_esc_obj()) { 1800 if (not_global_escape(alock->obj_node())) { 1801 assert(!alock->is_eliminated() || alock->is_coarsened(), "sanity"); 1802 // The lock could be marked eliminated by lock coarsening 1803 // code during first IGVN before EA. Replace coarsened flag 1804 // to eliminate all associated locks/unlocks. 1805 #ifdef ASSERT 1806 alock->log_lock_optimization(C, "eliminate_lock_set_non_esc3"); 1807 #endif 1808 alock->set_non_esc_obj(); 1809 } 1810 } 1811 } 1812 } 1813 } 1814 1815 if (OptimizePtrCompare) { 1816 // Add ConI(#CC_GT) and ConI(#CC_EQ). 1817 _pcmp_neq = igvn->makecon(TypeInt::CC_GT); 1818 _pcmp_eq = igvn->makecon(TypeInt::CC_EQ); 1819 // Optimize objects compare. 1820 while (ptr_cmp_worklist.length() != 0) { 1821 Node *n = ptr_cmp_worklist.pop(); 1822 Node *res = optimize_ptr_compare(n); 1823 if (res != NULL) { 1824 #ifndef PRODUCT 1825 if (PrintOptimizePtrCompare) { 1826 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")); 1827 if (Verbose) { 1828 n->dump(1); 1829 } 1830 } 1831 #endif 1832 igvn->replace_node(n, res); 1833 } 1834 } 1835 // cleanup 1836 if (_pcmp_neq->outcnt() == 0) 1837 igvn->hash_delete(_pcmp_neq); 1838 if (_pcmp_eq->outcnt() == 0) 1839 igvn->hash_delete(_pcmp_eq); 1840 } 1841 1842 // For MemBarStoreStore nodes added in library_call.cpp, check 1843 // escape status of associated AllocateNode and optimize out 1844 // MemBarStoreStore node if the allocated object never escapes. 1845 while (storestore_worklist.length() != 0) { 1846 Node *n = storestore_worklist.pop(); 1847 MemBarStoreStoreNode *storestore = n ->as_MemBarStoreStore(); 1848 Node *alloc = storestore->in(MemBarNode::Precedent)->in(0); 1849 assert (alloc->is_Allocate(), "storestore should point to AllocateNode"); 1850 if (not_global_escape(alloc)) { 1851 MemBarNode* mb = MemBarNode::make(C, Op_MemBarCPUOrder, Compile::AliasIdxBot); 1852 mb->init_req(TypeFunc::Memory, storestore->in(TypeFunc::Memory)); 1853 mb->init_req(TypeFunc::Control, storestore->in(TypeFunc::Control)); 1854 igvn->register_new_node_with_optimizer(mb); 1855 igvn->replace_node(storestore, mb); 1856 } 1857 } 1858 } 1859 1860 // Optimize objects compare. 1861 Node* ConnectionGraph::optimize_ptr_compare(Node* n) { 1862 assert(OptimizePtrCompare, "sanity"); 1863 PointsToNode* ptn1 = ptnode_adr(n->in(1)->_idx); 1864 PointsToNode* ptn2 = ptnode_adr(n->in(2)->_idx); 1865 JavaObjectNode* jobj1 = unique_java_object(n->in(1)); 1866 JavaObjectNode* jobj2 = unique_java_object(n->in(2)); 1867 assert(ptn1->is_JavaObject() || ptn1->is_LocalVar(), "sanity"); 1868 assert(ptn2->is_JavaObject() || ptn2->is_LocalVar(), "sanity"); 1869 1870 // Check simple cases first. 1871 if (jobj1 != NULL) { 1872 if (jobj1->escape_state() == PointsToNode::NoEscape) { 1873 if (jobj1 == jobj2) { 1874 // Comparing the same not escaping object. 1875 return _pcmp_eq; 1876 } 1877 Node* obj = jobj1->ideal_node(); 1878 // Comparing not escaping allocation. 1879 if ((obj->is_Allocate() || obj->is_CallStaticJava()) && 1880 !ptn2->points_to(jobj1)) { 1881 return _pcmp_neq; // This includes nullness check. 1882 } 1883 } 1884 } 1885 if (jobj2 != NULL) { 1886 if (jobj2->escape_state() == PointsToNode::NoEscape) { 1887 Node* obj = jobj2->ideal_node(); 1888 // Comparing not escaping allocation. 1889 if ((obj->is_Allocate() || obj->is_CallStaticJava()) && 1890 !ptn1->points_to(jobj2)) { 1891 return _pcmp_neq; // This includes nullness check. 1892 } 1893 } 1894 } 1895 if (jobj1 != NULL && jobj1 != phantom_obj && 1896 jobj2 != NULL && jobj2 != phantom_obj && 1897 jobj1->ideal_node()->is_Con() && 1898 jobj2->ideal_node()->is_Con()) { 1899 // Klass or String constants compare. Need to be careful with 1900 // compressed pointers - compare types of ConN and ConP instead of nodes. 1901 const Type* t1 = jobj1->ideal_node()->get_ptr_type(); 1902 const Type* t2 = jobj2->ideal_node()->get_ptr_type(); 1903 if (t1->make_ptr() == t2->make_ptr()) { 1904 return _pcmp_eq; 1905 } else { 1906 return _pcmp_neq; 1907 } 1908 } 1909 if (ptn1->meet(ptn2)) { 1910 return NULL; // Sets are not disjoint 1911 } 1912 1913 // Sets are disjoint. 1914 bool set1_has_unknown_ptr = ptn1->points_to(phantom_obj); 1915 bool set2_has_unknown_ptr = ptn2->points_to(phantom_obj); 1916 bool set1_has_null_ptr = ptn1->points_to(null_obj); 1917 bool set2_has_null_ptr = ptn2->points_to(null_obj); 1918 if (set1_has_unknown_ptr && set2_has_null_ptr || 1919 set2_has_unknown_ptr && set1_has_null_ptr) { 1920 // Check nullness of unknown object. 1921 return NULL; 1922 } 1923 1924 // Disjointness by itself is not sufficient since 1925 // alias analysis is not complete for escaped objects. 1926 // Disjoint sets are definitely unrelated only when 1927 // at least one set has only not escaping allocations. 1928 if (!set1_has_unknown_ptr && !set1_has_null_ptr) { 1929 if (ptn1->non_escaping_allocation()) { 1930 return _pcmp_neq; 1931 } 1932 } 1933 if (!set2_has_unknown_ptr && !set2_has_null_ptr) { 1934 if (ptn2->non_escaping_allocation()) { 1935 return _pcmp_neq; 1936 } 1937 } 1938 return NULL; 1939 } 1940 1941 // Connection Graph constuction functions. 1942 1943 void ConnectionGraph::add_local_var(Node *n, PointsToNode::EscapeState es) { 1944 PointsToNode* ptadr = _nodes.at(n->_idx); 1945 if (ptadr != NULL) { 1946 assert(ptadr->is_LocalVar() && ptadr->ideal_node() == n, "sanity"); 1947 return; 1948 } 1949 Compile* C = _compile; 1950 ptadr = new (C->comp_arena()) LocalVarNode(this, n, es); 1951 _nodes.at_put(n->_idx, ptadr); 1952 } 1953 1954 void ConnectionGraph::add_java_object(Node *n, PointsToNode::EscapeState es) { 1955 PointsToNode* ptadr = _nodes.at(n->_idx); 1956 if (ptadr != NULL) { 1957 assert(ptadr->is_JavaObject() && ptadr->ideal_node() == n, "sanity"); 1958 return; 1959 } 1960 Compile* C = _compile; 1961 ptadr = new (C->comp_arena()) JavaObjectNode(this, n, es); 1962 _nodes.at_put(n->_idx, ptadr); 1963 } 1964 1965 void ConnectionGraph::add_field(Node *n, PointsToNode::EscapeState es, int offset) { 1966 PointsToNode* ptadr = _nodes.at(n->_idx); 1967 if (ptadr != NULL) { 1968 assert(ptadr->is_Field() && ptadr->ideal_node() == n, "sanity"); 1969 return; 1970 } 1971 bool unsafe = false; 1972 bool is_oop = is_oop_field(n, offset, &unsafe); 1973 if (unsafe) { 1974 es = PointsToNode::GlobalEscape; 1975 } 1976 Compile* C = _compile; 1977 FieldNode* field = new (C->comp_arena()) FieldNode(this, n, es, offset, is_oop); 1978 _nodes.at_put(n->_idx, field); 1979 } 1980 1981 void ConnectionGraph::add_arraycopy(Node *n, PointsToNode::EscapeState es, 1982 PointsToNode* src, PointsToNode* dst) { 1983 assert(!src->is_Field() && !dst->is_Field(), "only for JavaObject and LocalVar"); 1984 assert((src != null_obj) && (dst != null_obj), "not for ConP NULL"); 1985 PointsToNode* ptadr = _nodes.at(n->_idx); 1986 if (ptadr != NULL) { 1987 assert(ptadr->is_Arraycopy() && ptadr->ideal_node() == n, "sanity"); 1988 return; 1989 } 1990 Compile* C = _compile; 1991 ptadr = new (C->comp_arena()) ArraycopyNode(this, n, es); 1992 _nodes.at_put(n->_idx, ptadr); 1993 // Add edge from arraycopy node to source object. 1994 (void)add_edge(ptadr, src); 1995 src->set_arraycopy_src(); 1996 // Add edge from destination object to arraycopy node. 1997 (void)add_edge(dst, ptadr); 1998 dst->set_arraycopy_dst(); 1999 } 2000 2001 bool ConnectionGraph::is_oop_field(Node* n, int offset, bool* unsafe) { 2002 const Type* adr_type = n->as_AddP()->bottom_type(); 2003 BasicType bt = T_INT; 2004 if (offset == Type::OffsetBot) { 2005 // Check only oop fields. 2006 if (!adr_type->isa_aryptr() || 2007 (adr_type->isa_aryptr()->klass() == NULL) || 2008 adr_type->isa_aryptr()->klass()->is_obj_array_klass()) { 2009 // OffsetBot is used to reference array's element. Ignore first AddP. 2010 if (find_second_addp(n, n->in(AddPNode::Base)) == NULL) { 2011 bt = T_OBJECT; 2012 } 2013 } 2014 } else if (offset != oopDesc::klass_offset_in_bytes()) { 2015 if (adr_type->isa_instptr()) { 2016 ciField* field = _compile->alias_type(adr_type->isa_instptr())->field(); 2017 if (field != NULL) { 2018 bt = field->layout_type(); 2019 } else { 2020 // Check for unsafe oop field access 2021 if (n->has_out_with(Op_StoreP, Op_LoadP, Op_StoreN, Op_LoadN)) { 2022 bt = T_OBJECT; 2023 (*unsafe) = true; 2024 } 2025 } 2026 } else if (adr_type->isa_aryptr()) { 2027 if (offset == arrayOopDesc::length_offset_in_bytes()) { 2028 // Ignore array length load. 2029 } else if (find_second_addp(n, n->in(AddPNode::Base)) != NULL) { 2030 // Ignore first AddP. 2031 } else { 2032 const Type* elemtype = adr_type->isa_aryptr()->elem(); 2033 bt = elemtype->array_element_basic_type(); 2034 } 2035 } else if (adr_type->isa_rawptr() || adr_type->isa_klassptr()) { 2036 // Allocation initialization, ThreadLocal field access, unsafe access 2037 if (n->has_out_with(Op_StoreP, Op_LoadP, Op_StoreN, Op_LoadN)) { 2038 bt = T_OBJECT; 2039 } 2040 } 2041 } 2042 return (bt == T_OBJECT || bt == T_NARROWOOP || bt == T_ARRAY); 2043 } 2044 2045 // Returns unique pointed java object or NULL. 2046 JavaObjectNode* ConnectionGraph::unique_java_object(Node *n) { 2047 assert(!_collecting, "should not call when contructed graph"); 2048 // If the node was created after the escape computation we can't answer. 2049 uint idx = n->_idx; 2050 if (idx >= nodes_size()) { 2051 return NULL; 2052 } 2053 PointsToNode* ptn = ptnode_adr(idx); 2054 if (ptn->is_JavaObject()) { 2055 return ptn->as_JavaObject(); 2056 } 2057 assert(ptn->is_LocalVar(), "sanity"); 2058 // Check all java objects it points to. 2059 JavaObjectNode* jobj = NULL; 2060 for (EdgeIterator i(ptn); i.has_next(); i.next()) { 2061 PointsToNode* e = i.get(); 2062 if (e->is_JavaObject()) { 2063 if (jobj == NULL) { 2064 jobj = e->as_JavaObject(); 2065 } else if (jobj != e) { 2066 return NULL; 2067 } 2068 } 2069 } 2070 return jobj; 2071 } 2072 2073 // Return true if this node points only to non-escaping allocations. 2074 bool PointsToNode::non_escaping_allocation() { 2075 if (is_JavaObject()) { 2076 Node* n = ideal_node(); 2077 if (n->is_Allocate() || n->is_CallStaticJava()) { 2078 return (escape_state() == PointsToNode::NoEscape); 2079 } else { 2080 return false; 2081 } 2082 } 2083 assert(is_LocalVar(), "sanity"); 2084 // Check all java objects it points to. 2085 for (EdgeIterator i(this); i.has_next(); i.next()) { 2086 PointsToNode* e = i.get(); 2087 if (e->is_JavaObject()) { 2088 Node* n = e->ideal_node(); 2089 if ((e->escape_state() != PointsToNode::NoEscape) || 2090 !(n->is_Allocate() || n->is_CallStaticJava())) { 2091 return false; 2092 } 2093 } 2094 } 2095 return true; 2096 } 2097 2098 // Return true if we know the node does not escape globally. 2099 bool ConnectionGraph::not_global_escape(Node *n) { 2100 assert(!_collecting, "should not call during graph construction"); 2101 // If the node was created after the escape computation we can't answer. 2102 uint idx = n->_idx; 2103 if (idx >= nodes_size()) { 2104 return false; 2105 } 2106 PointsToNode* ptn = ptnode_adr(idx); 2107 PointsToNode::EscapeState es = ptn->escape_state(); 2108 // If we have already computed a value, return it. 2109 if (es >= PointsToNode::GlobalEscape) 2110 return false; 2111 if (ptn->is_JavaObject()) { 2112 return true; // (es < PointsToNode::GlobalEscape); 2113 } 2114 assert(ptn->is_LocalVar(), "sanity"); 2115 // Check all java objects it points to. 2116 for (EdgeIterator i(ptn); i.has_next(); i.next()) { 2117 if (i.get()->escape_state() >= PointsToNode::GlobalEscape) 2118 return false; 2119 } 2120 return true; 2121 } 2122 2123 2124 // Helper functions 2125 2126 // Return true if this node points to specified node or nodes it points to. 2127 bool PointsToNode::points_to(JavaObjectNode* ptn) const { 2128 if (is_JavaObject()) { 2129 return (this == ptn); 2130 } 2131 assert(is_LocalVar() || is_Field(), "sanity"); 2132 for (EdgeIterator i(this); i.has_next(); i.next()) { 2133 if (i.get() == ptn) 2134 return true; 2135 } 2136 return false; 2137 } 2138 2139 // Return true if one node points to an other. 2140 bool PointsToNode::meet(PointsToNode* ptn) { 2141 if (this == ptn) { 2142 return true; 2143 } else if (ptn->is_JavaObject()) { 2144 return this->points_to(ptn->as_JavaObject()); 2145 } else if (this->is_JavaObject()) { 2146 return ptn->points_to(this->as_JavaObject()); 2147 } 2148 assert(this->is_LocalVar() && ptn->is_LocalVar(), "sanity"); 2149 int ptn_count = ptn->edge_count(); 2150 for (EdgeIterator i(this); i.has_next(); i.next()) { 2151 PointsToNode* this_e = i.get(); 2152 for (int j = 0; j < ptn_count; j++) { 2153 if (this_e == ptn->edge(j)) 2154 return true; 2155 } 2156 } 2157 return false; 2158 } 2159 2160 #ifdef ASSERT 2161 // Return true if bases point to this java object. 2162 bool FieldNode::has_base(JavaObjectNode* jobj) const { 2163 for (BaseIterator i(this); i.has_next(); i.next()) { 2164 if (i.get() == jobj) 2165 return true; 2166 } 2167 return false; 2168 } 2169 #endif 2170 2171 int ConnectionGraph::address_offset(Node* adr, PhaseTransform *phase) { 2172 const Type *adr_type = phase->type(adr); 2173 if (adr->is_AddP() && adr_type->isa_oopptr() == NULL && 2174 adr->in(AddPNode::Address)->is_Proj() && 2175 adr->in(AddPNode::Address)->in(0)->is_Allocate()) { 2176 // We are computing a raw address for a store captured by an Initialize 2177 // compute an appropriate address type. AddP cases #3 and #5 (see below). 2178 int offs = (int)phase->find_intptr_t_con(adr->in(AddPNode::Offset), Type::OffsetBot); 2179 assert(offs != Type::OffsetBot || 2180 adr->in(AddPNode::Address)->in(0)->is_AllocateArray(), 2181 "offset must be a constant or it is initialization of array"); 2182 return offs; 2183 } 2184 const TypePtr *t_ptr = adr_type->isa_ptr(); 2185 assert(t_ptr != NULL, "must be a pointer type"); 2186 return t_ptr->offset(); 2187 } 2188 2189 Node* ConnectionGraph::get_addp_base(Node *addp) { 2190 assert(addp->is_AddP(), "must be AddP"); 2191 // 2192 // AddP cases for Base and Address inputs: 2193 // case #1. Direct object's field reference: 2194 // Allocate 2195 // | 2196 // Proj #5 ( oop result ) 2197 // | 2198 // CheckCastPP (cast to instance type) 2199 // | | 2200 // AddP ( base == address ) 2201 // 2202 // case #2. Indirect object's field reference: 2203 // Phi 2204 // | 2205 // CastPP (cast to instance type) 2206 // | | 2207 // AddP ( base == address ) 2208 // 2209 // case #3. Raw object's field reference for Initialize node: 2210 // Allocate 2211 // | 2212 // Proj #5 ( oop result ) 2213 // top | 2214 // \ | 2215 // AddP ( base == top ) 2216 // 2217 // case #4. Array's element reference: 2218 // {CheckCastPP | CastPP} 2219 // | | | 2220 // | AddP ( array's element offset ) 2221 // | | 2222 // AddP ( array's offset ) 2223 // 2224 // case #5. Raw object's field reference for arraycopy stub call: 2225 // The inline_native_clone() case when the arraycopy stub is called 2226 // after the allocation before Initialize and CheckCastPP nodes. 2227 // Allocate 2228 // | 2229 // Proj #5 ( oop result ) 2230 // | | 2231 // AddP ( base == address ) 2232 // 2233 // case #6. Constant Pool, ThreadLocal, CastX2P or 2234 // Raw object's field reference: 2235 // {ConP, ThreadLocal, CastX2P, raw Load} 2236 // top | 2237 // \ | 2238 // AddP ( base == top ) 2239 // 2240 // case #7. Klass's field reference. 2241 // LoadKlass 2242 // | | 2243 // AddP ( base == address ) 2244 // 2245 // case #8. narrow Klass's field reference. 2246 // LoadNKlass 2247 // | 2248 // DecodeN 2249 // | | 2250 // AddP ( base == address ) 2251 // 2252 Node *base = addp->in(AddPNode::Base); 2253 if (base->uncast()->is_top()) { // The AddP case #3 and #6. 2254 base = addp->in(AddPNode::Address); 2255 while (base->is_AddP()) { 2256 // Case #6 (unsafe access) may have several chained AddP nodes. 2257 assert(base->in(AddPNode::Base)->uncast()->is_top(), "expected unsafe access address only"); 2258 base = base->in(AddPNode::Address); 2259 } 2260 Node* uncast_base = base->uncast(); 2261 int opcode = uncast_base->Opcode(); 2262 assert(opcode == Op_ConP || opcode == Op_ThreadLocal || 2263 opcode == Op_CastX2P || uncast_base->is_DecodeNarrowPtr() || 2264 (uncast_base->is_Mem() && (uncast_base->bottom_type()->isa_rawptr() != NULL)) || 2265 (uncast_base->is_Proj() && uncast_base->in(0)->is_Allocate()), "sanity"); 2266 } 2267 return base; 2268 } 2269 2270 Node* ConnectionGraph::find_second_addp(Node* addp, Node* n) { 2271 assert(addp->is_AddP() && addp->outcnt() > 0, "Don't process dead nodes"); 2272 Node* addp2 = addp->raw_out(0); 2273 if (addp->outcnt() == 1 && addp2->is_AddP() && 2274 addp2->in(AddPNode::Base) == n && 2275 addp2->in(AddPNode::Address) == addp) { 2276 assert(addp->in(AddPNode::Base) == n, "expecting the same base"); 2277 // 2278 // Find array's offset to push it on worklist first and 2279 // as result process an array's element offset first (pushed second) 2280 // to avoid CastPP for the array's offset. 2281 // Otherwise the inserted CastPP (LocalVar) will point to what 2282 // the AddP (Field) points to. Which would be wrong since 2283 // the algorithm expects the CastPP has the same point as 2284 // as AddP's base CheckCastPP (LocalVar). 2285 // 2286 // ArrayAllocation 2287 // | 2288 // CheckCastPP 2289 // | 2290 // memProj (from ArrayAllocation CheckCastPP) 2291 // | || 2292 // | || Int (element index) 2293 // | || | ConI (log(element size)) 2294 // | || | / 2295 // | || LShift 2296 // | || / 2297 // | AddP (array's element offset) 2298 // | | 2299 // | | ConI (array's offset: #12(32-bits) or #24(64-bits)) 2300 // | / / 2301 // AddP (array's offset) 2302 // | 2303 // Load/Store (memory operation on array's element) 2304 // 2305 return addp2; 2306 } 2307 return NULL; 2308 } 2309 2310 // 2311 // Adjust the type and inputs of an AddP which computes the 2312 // address of a field of an instance 2313 // 2314 bool ConnectionGraph::split_AddP(Node *addp, Node *base) { 2315 PhaseGVN* igvn = _igvn; 2316 const TypeOopPtr *base_t = igvn->type(base)->isa_oopptr(); 2317 assert(base_t != NULL && base_t->is_known_instance(), "expecting instance oopptr"); 2318 const TypeOopPtr *t = igvn->type(addp)->isa_oopptr(); 2319 if (t == NULL) { 2320 // We are computing a raw address for a store captured by an Initialize 2321 // compute an appropriate address type (cases #3 and #5). 2322 assert(igvn->type(addp) == TypeRawPtr::NOTNULL, "must be raw pointer"); 2323 assert(addp->in(AddPNode::Address)->is_Proj(), "base of raw address must be result projection from allocation"); 2324 intptr_t offs = (int)igvn->find_intptr_t_con(addp->in(AddPNode::Offset), Type::OffsetBot); 2325 assert(offs != Type::OffsetBot, "offset must be a constant"); 2326 t = base_t->add_offset(offs)->is_oopptr(); 2327 } 2328 int inst_id = base_t->instance_id(); 2329 assert(!t->is_known_instance() || t->instance_id() == inst_id, 2330 "old type must be non-instance or match new type"); 2331 2332 // The type 't' could be subclass of 'base_t'. 2333 // As result t->offset() could be large then base_t's size and it will 2334 // cause the failure in add_offset() with narrow oops since TypeOopPtr() 2335 // constructor verifies correctness of the offset. 2336 // 2337 // It could happened on subclass's branch (from the type profiling 2338 // inlining) which was not eliminated during parsing since the exactness 2339 // of the allocation type was not propagated to the subclass type check. 2340 // 2341 // Or the type 't' could be not related to 'base_t' at all. 2342 // It could happened when CHA type is different from MDO type on a dead path 2343 // (for example, from instanceof check) which is not collapsed during parsing. 2344 // 2345 // Do nothing for such AddP node and don't process its users since 2346 // this code branch will go away. 2347 // 2348 if (!t->is_known_instance() && 2349 !base_t->klass()->is_subtype_of(t->klass())) { 2350 return false; // bail out 2351 } 2352 const TypeOopPtr *tinst = base_t->add_offset(t->offset())->is_oopptr(); 2353 // Do NOT remove the next line: ensure a new alias index is allocated 2354 // for the instance type. Note: C++ will not remove it since the call 2355 // has side effect. 2356 int alias_idx = _compile->get_alias_index(tinst); 2357 igvn->set_type(addp, tinst); 2358 // record the allocation in the node map 2359 set_map(addp, get_map(base->_idx)); 2360 // Set addp's Base and Address to 'base'. 2361 Node *abase = addp->in(AddPNode::Base); 2362 Node *adr = addp->in(AddPNode::Address); 2363 if (adr->is_Proj() && adr->in(0)->is_Allocate() && 2364 adr->in(0)->_idx == (uint)inst_id) { 2365 // Skip AddP cases #3 and #5. 2366 } else { 2367 assert(!abase->is_top(), "sanity"); // AddP case #3 2368 if (abase != base) { 2369 igvn->hash_delete(addp); 2370 addp->set_req(AddPNode::Base, base); 2371 if (abase == adr) { 2372 addp->set_req(AddPNode::Address, base); 2373 } else { 2374 // AddP case #4 (adr is array's element offset AddP node) 2375 #ifdef ASSERT 2376 const TypeOopPtr *atype = igvn->type(adr)->isa_oopptr(); 2377 assert(adr->is_AddP() && atype != NULL && 2378 atype->instance_id() == inst_id, "array's element offset should be processed first"); 2379 #endif 2380 } 2381 igvn->hash_insert(addp); 2382 } 2383 } 2384 // Put on IGVN worklist since at least addp's type was changed above. 2385 record_for_optimizer(addp); 2386 return true; 2387 } 2388 2389 // 2390 // Create a new version of orig_phi if necessary. Returns either the newly 2391 // created phi or an existing phi. Sets create_new to indicate whether a new 2392 // phi was created. Cache the last newly created phi in the node map. 2393 // 2394 PhiNode *ConnectionGraph::create_split_phi(PhiNode *orig_phi, int alias_idx, GrowableArray<PhiNode *> &orig_phi_worklist, bool &new_created) { 2395 Compile *C = _compile; 2396 PhaseGVN* igvn = _igvn; 2397 new_created = false; 2398 int phi_alias_idx = C->get_alias_index(orig_phi->adr_type()); 2399 // nothing to do if orig_phi is bottom memory or matches alias_idx 2400 if (phi_alias_idx == alias_idx) { 2401 return orig_phi; 2402 } 2403 // Have we recently created a Phi for this alias index? 2404 PhiNode *result = get_map_phi(orig_phi->_idx); 2405 if (result != NULL && C->get_alias_index(result->adr_type()) == alias_idx) { 2406 return result; 2407 } 2408 // Previous check may fail when the same wide memory Phi was split into Phis 2409 // for different memory slices. Search all Phis for this region. 2410 if (result != NULL) { 2411 Node* region = orig_phi->in(0); 2412 for (DUIterator_Fast imax, i = region->fast_outs(imax); i < imax; i++) { 2413 Node* phi = region->fast_out(i); 2414 if (phi->is_Phi() && 2415 C->get_alias_index(phi->as_Phi()->adr_type()) == alias_idx) { 2416 assert(phi->_idx >= nodes_size(), "only new Phi per instance memory slice"); 2417 return phi->as_Phi(); 2418 } 2419 } 2420 } 2421 if (C->live_nodes() + 2*NodeLimitFudgeFactor > C->max_node_limit()) { 2422 if (C->do_escape_analysis() == true && !C->failing()) { 2423 // Retry compilation without escape analysis. 2424 // If this is the first failure, the sentinel string will "stick" 2425 // to the Compile object, and the C2Compiler will see it and retry. 2426 C->record_failure(C2Compiler::retry_no_escape_analysis()); 2427 } 2428 return NULL; 2429 } 2430 orig_phi_worklist.append_if_missing(orig_phi); 2431 const TypePtr *atype = C->get_adr_type(alias_idx); 2432 result = PhiNode::make(orig_phi->in(0), NULL, Type::MEMORY, atype); 2433 C->copy_node_notes_to(result, orig_phi); 2434 igvn->set_type(result, result->bottom_type()); 2435 record_for_optimizer(result); 2436 set_map(orig_phi, result); 2437 new_created = true; 2438 return result; 2439 } 2440 2441 // 2442 // Return a new version of Memory Phi "orig_phi" with the inputs having the 2443 // specified alias index. 2444 // 2445 PhiNode *ConnectionGraph::split_memory_phi(PhiNode *orig_phi, int alias_idx, GrowableArray<PhiNode *> &orig_phi_worklist) { 2446 assert(alias_idx != Compile::AliasIdxBot, "can't split out bottom memory"); 2447 Compile *C = _compile; 2448 PhaseGVN* igvn = _igvn; 2449 bool new_phi_created; 2450 PhiNode *result = create_split_phi(orig_phi, alias_idx, orig_phi_worklist, new_phi_created); 2451 if (!new_phi_created) { 2452 return result; 2453 } 2454 GrowableArray<PhiNode *> phi_list; 2455 GrowableArray<uint> cur_input; 2456 PhiNode *phi = orig_phi; 2457 uint idx = 1; 2458 bool finished = false; 2459 while(!finished) { 2460 while (idx < phi->req()) { 2461 Node *mem = find_inst_mem(phi->in(idx), alias_idx, orig_phi_worklist); 2462 if (mem != NULL && mem->is_Phi()) { 2463 PhiNode *newphi = create_split_phi(mem->as_Phi(), alias_idx, orig_phi_worklist, new_phi_created); 2464 if (new_phi_created) { 2465 // found an phi for which we created a new split, push current one on worklist and begin 2466 // processing new one 2467 phi_list.push(phi); 2468 cur_input.push(idx); 2469 phi = mem->as_Phi(); 2470 result = newphi; 2471 idx = 1; 2472 continue; 2473 } else { 2474 mem = newphi; 2475 } 2476 } 2477 if (C->failing()) { 2478 return NULL; 2479 } 2480 result->set_req(idx++, mem); 2481 } 2482 #ifdef ASSERT 2483 // verify that the new Phi has an input for each input of the original 2484 assert( phi->req() == result->req(), "must have same number of inputs."); 2485 assert( result->in(0) != NULL && result->in(0) == phi->in(0), "regions must match"); 2486 #endif 2487 // Check if all new phi's inputs have specified alias index. 2488 // Otherwise use old phi. 2489 for (uint i = 1; i < phi->req(); i++) { 2490 Node* in = result->in(i); 2491 assert((phi->in(i) == NULL) == (in == NULL), "inputs must correspond."); 2492 } 2493 // we have finished processing a Phi, see if there are any more to do 2494 finished = (phi_list.length() == 0 ); 2495 if (!finished) { 2496 phi = phi_list.pop(); 2497 idx = cur_input.pop(); 2498 PhiNode *prev_result = get_map_phi(phi->_idx); 2499 prev_result->set_req(idx++, result); 2500 result = prev_result; 2501 } 2502 } 2503 return result; 2504 } 2505 2506 // 2507 // The next methods are derived from methods in MemNode. 2508 // 2509 Node* ConnectionGraph::step_through_mergemem(MergeMemNode *mmem, int alias_idx, const TypeOopPtr *toop) { 2510 Node *mem = mmem; 2511 // TypeOopPtr::NOTNULL+any is an OOP with unknown offset - generally 2512 // means an array I have not precisely typed yet. Do not do any 2513 // alias stuff with it any time soon. 2514 if (toop->base() != Type::AnyPtr && 2515 !(toop->klass() != NULL && 2516 toop->klass()->is_java_lang_Object() && 2517 toop->offset() == Type::OffsetBot)) { 2518 mem = mmem->memory_at(alias_idx); 2519 // Update input if it is progress over what we have now 2520 } 2521 return mem; 2522 } 2523 2524 // 2525 // Move memory users to their memory slices. 2526 // 2527 void ConnectionGraph::move_inst_mem(Node* n, GrowableArray<PhiNode *> &orig_phis) { 2528 Compile* C = _compile; 2529 PhaseGVN* igvn = _igvn; 2530 const TypePtr* tp = igvn->type(n->in(MemNode::Address))->isa_ptr(); 2531 assert(tp != NULL, "ptr type"); 2532 int alias_idx = C->get_alias_index(tp); 2533 int general_idx = C->get_general_index(alias_idx); 2534 2535 // Move users first 2536 for (DUIterator_Fast imax, i = n->fast_outs(imax); i < imax; i++) { 2537 Node* use = n->fast_out(i); 2538 if (use->is_MergeMem()) { 2539 MergeMemNode* mmem = use->as_MergeMem(); 2540 assert(n == mmem->memory_at(alias_idx), "should be on instance memory slice"); 2541 if (n != mmem->memory_at(general_idx) || alias_idx == general_idx) { 2542 continue; // Nothing to do 2543 } 2544 // Replace previous general reference to mem node. 2545 uint orig_uniq = C->unique(); 2546 Node* m = find_inst_mem(n, general_idx, orig_phis); 2547 assert(orig_uniq == C->unique(), "no new nodes"); 2548 mmem->set_memory_at(general_idx, m); 2549 --imax; 2550 --i; 2551 } else if (use->is_MemBar()) { 2552 assert(!use->is_Initialize(), "initializing stores should not be moved"); 2553 if (use->req() > MemBarNode::Precedent && 2554 use->in(MemBarNode::Precedent) == n) { 2555 // Don't move related membars. 2556 record_for_optimizer(use); 2557 continue; 2558 } 2559 tp = use->as_MemBar()->adr_type()->isa_ptr(); 2560 if (tp != NULL && C->get_alias_index(tp) == alias_idx || 2561 alias_idx == general_idx) { 2562 continue; // Nothing to do 2563 } 2564 // Move to general memory slice. 2565 uint orig_uniq = C->unique(); 2566 Node* m = find_inst_mem(n, general_idx, orig_phis); 2567 assert(orig_uniq == C->unique(), "no new nodes"); 2568 igvn->hash_delete(use); 2569 imax -= use->replace_edge(n, m); 2570 igvn->hash_insert(use); 2571 record_for_optimizer(use); 2572 --i; 2573 #ifdef ASSERT 2574 } else if (use->is_Mem()) { 2575 if (use->Opcode() == Op_StoreCM && use->in(MemNode::OopStore) == n) { 2576 // Don't move related cardmark. 2577 continue; 2578 } 2579 // Memory nodes should have new memory input. 2580 tp = igvn->type(use->in(MemNode::Address))->isa_ptr(); 2581 assert(tp != NULL, "ptr type"); 2582 int idx = C->get_alias_index(tp); 2583 assert(get_map(use->_idx) != NULL || idx == alias_idx, 2584 "Following memory nodes should have new memory input or be on the same memory slice"); 2585 } else if (use->is_Phi()) { 2586 // Phi nodes should be split and moved already. 2587 tp = use->as_Phi()->adr_type()->isa_ptr(); 2588 assert(tp != NULL, "ptr type"); 2589 int idx = C->get_alias_index(tp); 2590 assert(idx == alias_idx, "Following Phi nodes should be on the same memory slice"); 2591 } else { 2592 use->dump(); 2593 assert(false, "should not be here"); 2594 #endif 2595 } 2596 } 2597 } 2598 2599 // 2600 // Search memory chain of "mem" to find a MemNode whose address 2601 // is the specified alias index. 2602 // 2603 Node* ConnectionGraph::find_inst_mem(Node *orig_mem, int alias_idx, GrowableArray<PhiNode *> &orig_phis) { 2604 if (orig_mem == NULL) 2605 return orig_mem; 2606 Compile* C = _compile; 2607 PhaseGVN* igvn = _igvn; 2608 const TypeOopPtr *toop = C->get_adr_type(alias_idx)->isa_oopptr(); 2609 bool is_instance = (toop != NULL) && toop->is_known_instance(); 2610 Node *start_mem = C->start()->proj_out(TypeFunc::Memory); 2611 Node *prev = NULL; 2612 Node *result = orig_mem; 2613 while (prev != result) { 2614 prev = result; 2615 if (result == start_mem) 2616 break; // hit one of our sentinels 2617 if (result->is_Mem()) { 2618 const Type *at = igvn->type(result->in(MemNode::Address)); 2619 if (at == Type::TOP) 2620 break; // Dead 2621 assert (at->isa_ptr() != NULL, "pointer type required."); 2622 int idx = C->get_alias_index(at->is_ptr()); 2623 if (idx == alias_idx) 2624 break; // Found 2625 if (!is_instance && (at->isa_oopptr() == NULL || 2626 !at->is_oopptr()->is_known_instance())) { 2627 break; // Do not skip store to general memory slice. 2628 } 2629 result = result->in(MemNode::Memory); 2630 } 2631 if (!is_instance) 2632 continue; // don't search further for non-instance types 2633 // skip over a call which does not affect this memory slice 2634 if (result->is_Proj() && result->as_Proj()->_con == TypeFunc::Memory) { 2635 Node *proj_in = result->in(0); 2636 if (proj_in->is_Allocate() && proj_in->_idx == (uint)toop->instance_id()) { 2637 break; // hit one of our sentinels 2638 } else if (proj_in->is_Call()) { 2639 CallNode *call = proj_in->as_Call(); 2640 if (!call->may_modify(toop, igvn)) { 2641 result = call->in(TypeFunc::Memory); 2642 } 2643 } else if (proj_in->is_Initialize()) { 2644 AllocateNode* alloc = proj_in->as_Initialize()->allocation(); 2645 // Stop if this is the initialization for the object instance which 2646 // which contains this memory slice, otherwise skip over it. 2647 if (alloc == NULL || alloc->_idx != (uint)toop->instance_id()) { 2648 result = proj_in->in(TypeFunc::Memory); 2649 } 2650 } else if (proj_in->is_MemBar()) { 2651 result = proj_in->in(TypeFunc::Memory); 2652 } 2653 } else if (result->is_MergeMem()) { 2654 MergeMemNode *mmem = result->as_MergeMem(); 2655 result = step_through_mergemem(mmem, alias_idx, toop); 2656 if (result == mmem->base_memory()) { 2657 // Didn't find instance memory, search through general slice recursively. 2658 result = mmem->memory_at(C->get_general_index(alias_idx)); 2659 result = find_inst_mem(result, alias_idx, orig_phis); 2660 if (C->failing()) { 2661 return NULL; 2662 } 2663 mmem->set_memory_at(alias_idx, result); 2664 } 2665 } else if (result->is_Phi() && 2666 C->get_alias_index(result->as_Phi()->adr_type()) != alias_idx) { 2667 Node *un = result->as_Phi()->unique_input(igvn); 2668 if (un != NULL) { 2669 orig_phis.append_if_missing(result->as_Phi()); 2670 result = un; 2671 } else { 2672 break; 2673 } 2674 } else if (result->is_ClearArray()) { 2675 if (!ClearArrayNode::step_through(&result, (uint)toop->instance_id(), igvn)) { 2676 // Can not bypass initialization of the instance 2677 // we are looking for. 2678 break; 2679 } 2680 // Otherwise skip it (the call updated 'result' value). 2681 } else if (result->Opcode() == Op_SCMemProj) { 2682 Node* mem = result->in(0); 2683 Node* adr = NULL; 2684 if (mem->is_LoadStore()) { 2685 adr = mem->in(MemNode::Address); 2686 } else { 2687 assert(mem->Opcode() == Op_EncodeISOArray, "sanity"); 2688 adr = mem->in(3); // Memory edge corresponds to destination array 2689 } 2690 const Type *at = igvn->type(adr); 2691 if (at != Type::TOP) { 2692 assert (at->isa_ptr() != NULL, "pointer type required."); 2693 int idx = C->get_alias_index(at->is_ptr()); 2694 assert(idx != alias_idx, "Object is not scalar replaceable if a LoadStore node access its field"); 2695 break; 2696 } 2697 result = mem->in(MemNode::Memory); 2698 } 2699 } 2700 if (result->is_Phi()) { 2701 PhiNode *mphi = result->as_Phi(); 2702 assert(mphi->bottom_type() == Type::MEMORY, "memory phi required"); 2703 const TypePtr *t = mphi->adr_type(); 2704 if (!is_instance) { 2705 // Push all non-instance Phis on the orig_phis worklist to update inputs 2706 // during Phase 4 if needed. 2707 orig_phis.append_if_missing(mphi); 2708 } else if (C->get_alias_index(t) != alias_idx) { 2709 // Create a new Phi with the specified alias index type. 2710 result = split_memory_phi(mphi, alias_idx, orig_phis); 2711 } 2712 } 2713 // the result is either MemNode, PhiNode, InitializeNode. 2714 return result; 2715 } 2716 2717 // 2718 // Convert the types of unescaped object to instance types where possible, 2719 // propagate the new type information through the graph, and update memory 2720 // edges and MergeMem inputs to reflect the new type. 2721 // 2722 // We start with allocations (and calls which may be allocations) on alloc_worklist. 2723 // The processing is done in 4 phases: 2724 // 2725 // Phase 1: Process possible allocations from alloc_worklist. Create instance 2726 // types for the CheckCastPP for allocations where possible. 2727 // Propagate the the new types through users as follows: 2728 // casts and Phi: push users on alloc_worklist 2729 // AddP: cast Base and Address inputs to the instance type 2730 // push any AddP users on alloc_worklist and push any memnode 2731 // users onto memnode_worklist. 2732 // Phase 2: Process MemNode's from memnode_worklist. compute new address type and 2733 // search the Memory chain for a store with the appropriate type 2734 // address type. If a Phi is found, create a new version with 2735 // the appropriate memory slices from each of the Phi inputs. 2736 // For stores, process the users as follows: 2737 // MemNode: push on memnode_worklist 2738 // MergeMem: push on mergemem_worklist 2739 // Phase 3: Process MergeMem nodes from mergemem_worklist. Walk each memory slice 2740 // moving the first node encountered of each instance type to the 2741 // the input corresponding to its alias index. 2742 // appropriate memory slice. 2743 // Phase 4: Update the inputs of non-instance memory Phis and the Memory input of memnodes. 2744 // 2745 // In the following example, the CheckCastPP nodes are the cast of allocation 2746 // results and the allocation of node 29 is unescaped and eligible to be an 2747 // instance type. 2748 // 2749 // We start with: 2750 // 2751 // 7 Parm #memory 2752 // 10 ConI "12" 2753 // 19 CheckCastPP "Foo" 2754 // 20 AddP _ 19 19 10 Foo+12 alias_index=4 2755 // 29 CheckCastPP "Foo" 2756 // 30 AddP _ 29 29 10 Foo+12 alias_index=4 2757 // 2758 // 40 StoreP 25 7 20 ... alias_index=4 2759 // 50 StoreP 35 40 30 ... alias_index=4 2760 // 60 StoreP 45 50 20 ... alias_index=4 2761 // 70 LoadP _ 60 30 ... alias_index=4 2762 // 80 Phi 75 50 60 Memory alias_index=4 2763 // 90 LoadP _ 80 30 ... alias_index=4 2764 // 100 LoadP _ 80 20 ... alias_index=4 2765 // 2766 // 2767 // Phase 1 creates an instance type for node 29 assigning it an instance id of 24 2768 // and creating a new alias index for node 30. This gives: 2769 // 2770 // 7 Parm #memory 2771 // 10 ConI "12" 2772 // 19 CheckCastPP "Foo" 2773 // 20 AddP _ 19 19 10 Foo+12 alias_index=4 2774 // 29 CheckCastPP "Foo" iid=24 2775 // 30 AddP _ 29 29 10 Foo+12 alias_index=6 iid=24 2776 // 2777 // 40 StoreP 25 7 20 ... alias_index=4 2778 // 50 StoreP 35 40 30 ... alias_index=6 2779 // 60 StoreP 45 50 20 ... alias_index=4 2780 // 70 LoadP _ 60 30 ... alias_index=6 2781 // 80 Phi 75 50 60 Memory alias_index=4 2782 // 90 LoadP _ 80 30 ... alias_index=6 2783 // 100 LoadP _ 80 20 ... alias_index=4 2784 // 2785 // In phase 2, new memory inputs are computed for the loads and stores, 2786 // And a new version of the phi is created. In phase 4, the inputs to 2787 // node 80 are updated and then the memory nodes are updated with the 2788 // values computed in phase 2. This results in: 2789 // 2790 // 7 Parm #memory 2791 // 10 ConI "12" 2792 // 19 CheckCastPP "Foo" 2793 // 20 AddP _ 19 19 10 Foo+12 alias_index=4 2794 // 29 CheckCastPP "Foo" iid=24 2795 // 30 AddP _ 29 29 10 Foo+12 alias_index=6 iid=24 2796 // 2797 // 40 StoreP 25 7 20 ... alias_index=4 2798 // 50 StoreP 35 7 30 ... alias_index=6 2799 // 60 StoreP 45 40 20 ... alias_index=4 2800 // 70 LoadP _ 50 30 ... alias_index=6 2801 // 80 Phi 75 40 60 Memory alias_index=4 2802 // 120 Phi 75 50 50 Memory alias_index=6 2803 // 90 LoadP _ 120 30 ... alias_index=6 2804 // 100 LoadP _ 80 20 ... alias_index=4 2805 // 2806 void ConnectionGraph::split_unique_types(GrowableArray<Node *> &alloc_worklist) { 2807 GrowableArray<Node *> memnode_worklist; 2808 GrowableArray<PhiNode *> orig_phis; 2809 PhaseIterGVN *igvn = _igvn; 2810 uint new_index_start = (uint) _compile->num_alias_types(); 2811 Arena* arena = Thread::current()->resource_area(); 2812 VectorSet visited(arena); 2813 ideal_nodes.clear(); // Reset for use with set_map/get_map. 2814 uint unique_old = _compile->unique(); 2815 2816 // Phase 1: Process possible allocations from alloc_worklist. 2817 // Create instance types for the CheckCastPP for allocations where possible. 2818 // 2819 // (Note: don't forget to change the order of the second AddP node on 2820 // the alloc_worklist if the order of the worklist processing is changed, 2821 // see the comment in find_second_addp().) 2822 // 2823 while (alloc_worklist.length() != 0) { 2824 Node *n = alloc_worklist.pop(); 2825 uint ni = n->_idx; 2826 if (n->is_Call()) { 2827 CallNode *alloc = n->as_Call(); 2828 // copy escape information to call node 2829 PointsToNode* ptn = ptnode_adr(alloc->_idx); 2830 PointsToNode::EscapeState es = ptn->escape_state(); 2831 // We have an allocation or call which returns a Java object, 2832 // see if it is unescaped. 2833 if (es != PointsToNode::NoEscape || !ptn->scalar_replaceable()) 2834 continue; 2835 // Find CheckCastPP for the allocate or for the return value of a call 2836 n = alloc->result_cast(); 2837 if (n == NULL) { // No uses except Initialize node 2838 if (alloc->is_Allocate()) { 2839 // Set the scalar_replaceable flag for allocation 2840 // so it could be eliminated if it has no uses. 2841 alloc->as_Allocate()->_is_scalar_replaceable = true; 2842 } 2843 if (alloc->is_CallStaticJava()) { 2844 // Set the scalar_replaceable flag for boxing method 2845 // so it could be eliminated if it has no uses. 2846 alloc->as_CallStaticJava()->_is_scalar_replaceable = true; 2847 } 2848 continue; 2849 } 2850 if (!n->is_CheckCastPP()) { // not unique CheckCastPP. 2851 assert(!alloc->is_Allocate(), "allocation should have unique type"); 2852 continue; 2853 } 2854 2855 // The inline code for Object.clone() casts the allocation result to 2856 // java.lang.Object and then to the actual type of the allocated 2857 // object. Detect this case and use the second cast. 2858 // Also detect j.l.reflect.Array.newInstance(jobject, jint) case when 2859 // the allocation result is cast to java.lang.Object and then 2860 // to the actual Array type. 2861 if (alloc->is_Allocate() && n->as_Type()->type() == TypeInstPtr::NOTNULL 2862 && (alloc->is_AllocateArray() || 2863 igvn->type(alloc->in(AllocateNode::KlassNode)) != TypeKlassPtr::OBJECT)) { 2864 Node *cast2 = NULL; 2865 for (DUIterator_Fast imax, i = n->fast_outs(imax); i < imax; i++) { 2866 Node *use = n->fast_out(i); 2867 if (use->is_CheckCastPP()) { 2868 cast2 = use; 2869 break; 2870 } 2871 } 2872 if (cast2 != NULL) { 2873 n = cast2; 2874 } else { 2875 // Non-scalar replaceable if the allocation type is unknown statically 2876 // (reflection allocation), the object can't be restored during 2877 // deoptimization without precise type. 2878 continue; 2879 } 2880 } 2881 2882 const TypeOopPtr *t = igvn->type(n)->isa_oopptr(); 2883 if (t == NULL) 2884 continue; // not a TypeOopPtr 2885 if (!t->klass_is_exact()) 2886 continue; // not an unique type 2887 2888 if (alloc->is_Allocate()) { 2889 // Set the scalar_replaceable flag for allocation 2890 // so it could be eliminated. 2891 alloc->as_Allocate()->_is_scalar_replaceable = true; 2892 } 2893 if (alloc->is_CallStaticJava()) { 2894 // Set the scalar_replaceable flag for boxing method 2895 // so it could be eliminated. 2896 alloc->as_CallStaticJava()->_is_scalar_replaceable = true; 2897 } 2898 set_escape_state(ptnode_adr(n->_idx), es); // CheckCastPP escape state 2899 // in order for an object to be scalar-replaceable, it must be: 2900 // - a direct allocation (not a call returning an object) 2901 // - non-escaping 2902 // - eligible to be a unique type 2903 // - not determined to be ineligible by escape analysis 2904 set_map(alloc, n); 2905 set_map(n, alloc); 2906 const TypeOopPtr* tinst = t->cast_to_instance_id(ni); 2907 igvn->hash_delete(n); 2908 igvn->set_type(n, tinst); 2909 n->raise_bottom_type(tinst); 2910 igvn->hash_insert(n); 2911 record_for_optimizer(n); 2912 if (alloc->is_Allocate() && (t->isa_instptr() || t->isa_aryptr())) { 2913 2914 // First, put on the worklist all Field edges from Connection Graph 2915 // which is more accurate then putting immediate users from Ideal Graph. 2916 for (EdgeIterator e(ptn); e.has_next(); e.next()) { 2917 PointsToNode* tgt = e.get(); 2918 Node* use = tgt->ideal_node(); 2919 assert(tgt->is_Field() && use->is_AddP(), 2920 "only AddP nodes are Field edges in CG"); 2921 if (use->outcnt() > 0) { // Don't process dead nodes 2922 Node* addp2 = find_second_addp(use, use->in(AddPNode::Base)); 2923 if (addp2 != NULL) { 2924 assert(alloc->is_AllocateArray(),"array allocation was expected"); 2925 alloc_worklist.append_if_missing(addp2); 2926 } 2927 alloc_worklist.append_if_missing(use); 2928 } 2929 } 2930 2931 // An allocation may have an Initialize which has raw stores. Scan 2932 // the users of the raw allocation result and push AddP users 2933 // on alloc_worklist. 2934 Node *raw_result = alloc->proj_out(TypeFunc::Parms); 2935 assert (raw_result != NULL, "must have an allocation result"); 2936 for (DUIterator_Fast imax, i = raw_result->fast_outs(imax); i < imax; i++) { 2937 Node *use = raw_result->fast_out(i); 2938 if (use->is_AddP() && use->outcnt() > 0) { // Don't process dead nodes 2939 Node* addp2 = find_second_addp(use, raw_result); 2940 if (addp2 != NULL) { 2941 assert(alloc->is_AllocateArray(),"array allocation was expected"); 2942 alloc_worklist.append_if_missing(addp2); 2943 } 2944 alloc_worklist.append_if_missing(use); 2945 } else if (use->is_MemBar()) { 2946 memnode_worklist.append_if_missing(use); 2947 } 2948 } 2949 } 2950 } else if (n->is_AddP()) { 2951 JavaObjectNode* jobj = unique_java_object(get_addp_base(n)); 2952 if (jobj == NULL || jobj == phantom_obj) { 2953 #ifdef ASSERT 2954 ptnode_adr(get_addp_base(n)->_idx)->dump(); 2955 ptnode_adr(n->_idx)->dump(); 2956 assert(jobj != NULL && jobj != phantom_obj, "escaped allocation"); 2957 #endif 2958 _compile->record_failure(C2Compiler::retry_no_escape_analysis()); 2959 return; 2960 } 2961 Node *base = get_map(jobj->idx()); // CheckCastPP node 2962 if (!split_AddP(n, base)) continue; // wrong type from dead path 2963 } else if (n->is_Phi() || 2964 n->is_CheckCastPP() || 2965 n->is_EncodeP() || 2966 n->is_DecodeN() || 2967 (n->is_ConstraintCast() && n->Opcode() == Op_CastPP)) { 2968 if (visited.test_set(n->_idx)) { 2969 assert(n->is_Phi(), "loops only through Phi's"); 2970 continue; // already processed 2971 } 2972 JavaObjectNode* jobj = unique_java_object(n); 2973 if (jobj == NULL || jobj == phantom_obj) { 2974 #ifdef ASSERT 2975 ptnode_adr(n->_idx)->dump(); 2976 assert(jobj != NULL && jobj != phantom_obj, "escaped allocation"); 2977 #endif 2978 _compile->record_failure(C2Compiler::retry_no_escape_analysis()); 2979 return; 2980 } else { 2981 Node *val = get_map(jobj->idx()); // CheckCastPP node 2982 TypeNode *tn = n->as_Type(); 2983 const TypeOopPtr* tinst = igvn->type(val)->isa_oopptr(); 2984 assert(tinst != NULL && tinst->is_known_instance() && 2985 tinst->instance_id() == jobj->idx() , "instance type expected."); 2986 2987 const Type *tn_type = igvn->type(tn); 2988 const TypeOopPtr *tn_t; 2989 if (tn_type->isa_narrowoop()) { 2990 tn_t = tn_type->make_ptr()->isa_oopptr(); 2991 } else { 2992 tn_t = tn_type->isa_oopptr(); 2993 } 2994 if (tn_t != NULL && tinst->klass()->is_subtype_of(tn_t->klass())) { 2995 if (tn_type->isa_narrowoop()) { 2996 tn_type = tinst->make_narrowoop(); 2997 } else { 2998 tn_type = tinst; 2999 } 3000 igvn->hash_delete(tn); 3001 igvn->set_type(tn, tn_type); 3002 tn->set_type(tn_type); 3003 igvn->hash_insert(tn); 3004 record_for_optimizer(n); 3005 } else { 3006 assert(tn_type == TypePtr::NULL_PTR || 3007 tn_t != NULL && !tinst->klass()->is_subtype_of(tn_t->klass()), 3008 "unexpected type"); 3009 continue; // Skip dead path with different type 3010 } 3011 } 3012 } else { 3013 debug_only(n->dump();) 3014 assert(false, "EA: unexpected node"); 3015 continue; 3016 } 3017 // push allocation's users on appropriate worklist 3018 for (DUIterator_Fast imax, i = n->fast_outs(imax); i < imax; i++) { 3019 Node *use = n->fast_out(i); 3020 if(use->is_Mem() && use->in(MemNode::Address) == n) { 3021 // Load/store to instance's field 3022 memnode_worklist.append_if_missing(use); 3023 } else if (use->is_MemBar()) { 3024 if (use->in(TypeFunc::Memory) == n) { // Ignore precedent edge 3025 memnode_worklist.append_if_missing(use); 3026 } 3027 } else if (use->is_AddP() && use->outcnt() > 0) { // No dead nodes 3028 Node* addp2 = find_second_addp(use, n); 3029 if (addp2 != NULL) { 3030 alloc_worklist.append_if_missing(addp2); 3031 } 3032 alloc_worklist.append_if_missing(use); 3033 } else if (use->is_Phi() || 3034 use->is_CheckCastPP() || 3035 use->is_EncodeNarrowPtr() || 3036 use->is_DecodeNarrowPtr() || 3037 (use->is_ConstraintCast() && use->Opcode() == Op_CastPP)) { 3038 alloc_worklist.append_if_missing(use); 3039 #ifdef ASSERT 3040 } else if (use->is_Mem()) { 3041 assert(use->in(MemNode::Address) != n, "EA: missing allocation reference path"); 3042 } else if (use->is_MergeMem()) { 3043 assert(_mergemem_worklist.contains(use->as_MergeMem()), "EA: missing MergeMem node in the worklist"); 3044 } else if (use->is_SafePoint()) { 3045 // Look for MergeMem nodes for calls which reference unique allocation 3046 // (through CheckCastPP nodes) even for debug info. 3047 Node* m = use->in(TypeFunc::Memory); 3048 if (m->is_MergeMem()) { 3049 assert(_mergemem_worklist.contains(m->as_MergeMem()), "EA: missing MergeMem node in the worklist"); 3050 } 3051 } else if (use->Opcode() == Op_EncodeISOArray) { 3052 if (use->in(MemNode::Memory) == n || use->in(3) == n) { 3053 // EncodeISOArray overwrites destination array 3054 memnode_worklist.append_if_missing(use); 3055 } 3056 } else { 3057 uint op = use->Opcode(); 3058 if (!(op == Op_CmpP || op == Op_Conv2B || 3059 op == Op_CastP2X || op == Op_StoreCM || 3060 op == Op_FastLock || op == Op_AryEq || op == Op_StrComp || 3061 op == Op_StrEquals || op == Op_StrIndexOf)) { 3062 n->dump(); 3063 use->dump(); 3064 assert(false, "EA: missing allocation reference path"); 3065 } 3066 #endif 3067 } 3068 } 3069 3070 } 3071 // New alias types were created in split_AddP(). 3072 uint new_index_end = (uint) _compile->num_alias_types(); 3073 assert(unique_old == _compile->unique(), "there should be no new ideal nodes after Phase 1"); 3074 3075 // Phase 2: Process MemNode's from memnode_worklist. compute new address type and 3076 // compute new values for Memory inputs (the Memory inputs are not 3077 // actually updated until phase 4.) 3078 if (memnode_worklist.length() == 0) 3079 return; // nothing to do 3080 while (memnode_worklist.length() != 0) { 3081 Node *n = memnode_worklist.pop(); 3082 if (visited.test_set(n->_idx)) 3083 continue; 3084 if (n->is_Phi() || n->is_ClearArray()) { 3085 // we don't need to do anything, but the users must be pushed 3086 } else if (n->is_MemBar()) { // Initialize, MemBar nodes 3087 // we don't need to do anything, but the users must be pushed 3088 n = n->as_MemBar()->proj_out(TypeFunc::Memory); 3089 if (n == NULL) 3090 continue; 3091 } else if (n->Opcode() == Op_EncodeISOArray) { 3092 // get the memory projection 3093 n = n->find_out_with(Op_SCMemProj); 3094 assert(n->Opcode() == Op_SCMemProj, "memory projection required"); 3095 } else { 3096 assert(n->is_Mem(), "memory node required."); 3097 Node *addr = n->in(MemNode::Address); 3098 const Type *addr_t = igvn->type(addr); 3099 if (addr_t == Type::TOP) 3100 continue; 3101 assert (addr_t->isa_ptr() != NULL, "pointer type required."); 3102 int alias_idx = _compile->get_alias_index(addr_t->is_ptr()); 3103 assert ((uint)alias_idx < new_index_end, "wrong alias index"); 3104 Node *mem = find_inst_mem(n->in(MemNode::Memory), alias_idx, orig_phis); 3105 if (_compile->failing()) { 3106 return; 3107 } 3108 if (mem != n->in(MemNode::Memory)) { 3109 // We delay the memory edge update since we need old one in 3110 // MergeMem code below when instances memory slices are separated. 3111 set_map(n, mem); 3112 } 3113 if (n->is_Load()) { 3114 continue; // don't push users 3115 } else if (n->is_LoadStore()) { 3116 // get the memory projection 3117 n = n->find_out_with(Op_SCMemProj); 3118 assert(n->Opcode() == Op_SCMemProj, "memory projection required"); 3119 } 3120 } 3121 // push user on appropriate worklist 3122 for (DUIterator_Fast imax, i = n->fast_outs(imax); i < imax; i++) { 3123 Node *use = n->fast_out(i); 3124 if (use->is_Phi() || use->is_ClearArray()) { 3125 memnode_worklist.append_if_missing(use); 3126 } else if (use->is_Mem() && use->in(MemNode::Memory) == n) { 3127 if (use->Opcode() == Op_StoreCM) // Ignore cardmark stores 3128 continue; 3129 memnode_worklist.append_if_missing(use); 3130 } else if (use->is_MemBar()) { 3131 if (use->in(TypeFunc::Memory) == n) { // Ignore precedent edge 3132 memnode_worklist.append_if_missing(use); 3133 } 3134 #ifdef ASSERT 3135 } else if(use->is_Mem()) { 3136 assert(use->in(MemNode::Memory) != n, "EA: missing memory path"); 3137 } else if (use->is_MergeMem()) { 3138 assert(_mergemem_worklist.contains(use->as_MergeMem()), "EA: missing MergeMem node in the worklist"); 3139 } else if (use->Opcode() == Op_EncodeISOArray) { 3140 if (use->in(MemNode::Memory) == n || use->in(3) == n) { 3141 // EncodeISOArray overwrites destination array 3142 memnode_worklist.append_if_missing(use); 3143 } 3144 } else { 3145 uint op = use->Opcode(); 3146 if (!(op == Op_StoreCM || 3147 (op == Op_CallLeaf && use->as_CallLeaf()->_name != NULL && 3148 strcmp(use->as_CallLeaf()->_name, "g1_wb_pre") == 0) || 3149 op == Op_AryEq || op == Op_StrComp || 3150 op == Op_StrEquals || op == Op_StrIndexOf)) { 3151 n->dump(); 3152 use->dump(); 3153 assert(false, "EA: missing memory path"); 3154 } 3155 #endif 3156 } 3157 } 3158 } 3159 3160 // Phase 3: Process MergeMem nodes from mergemem_worklist. 3161 // Walk each memory slice moving the first node encountered of each 3162 // instance type to the the input corresponding to its alias index. 3163 uint length = _mergemem_worklist.length(); 3164 for( uint next = 0; next < length; ++next ) { 3165 MergeMemNode* nmm = _mergemem_worklist.at(next); 3166 assert(!visited.test_set(nmm->_idx), "should not be visited before"); 3167 // Note: we don't want to use MergeMemStream here because we only want to 3168 // scan inputs which exist at the start, not ones we add during processing. 3169 // Note 2: MergeMem may already contains instance memory slices added 3170 // during find_inst_mem() call when memory nodes were processed above. 3171 igvn->hash_delete(nmm); 3172 uint nslices = nmm->req(); 3173 for (uint i = Compile::AliasIdxRaw+1; i < nslices; i++) { 3174 Node* mem = nmm->in(i); 3175 Node* cur = NULL; 3176 if (mem == NULL || mem->is_top()) 3177 continue; 3178 // First, update mergemem by moving memory nodes to corresponding slices 3179 // if their type became more precise since this mergemem was created. 3180 while (mem->is_Mem()) { 3181 const Type *at = igvn->type(mem->in(MemNode::Address)); 3182 if (at != Type::TOP) { 3183 assert (at->isa_ptr() != NULL, "pointer type required."); 3184 uint idx = (uint)_compile->get_alias_index(at->is_ptr()); 3185 if (idx == i) { 3186 if (cur == NULL) 3187 cur = mem; 3188 } else { 3189 if (idx >= nmm->req() || nmm->is_empty_memory(nmm->in(idx))) { 3190 nmm->set_memory_at(idx, mem); 3191 } 3192 } 3193 } 3194 mem = mem->in(MemNode::Memory); 3195 } 3196 nmm->set_memory_at(i, (cur != NULL) ? cur : mem); 3197 // Find any instance of the current type if we haven't encountered 3198 // already a memory slice of the instance along the memory chain. 3199 for (uint ni = new_index_start; ni < new_index_end; ni++) { 3200 if((uint)_compile->get_general_index(ni) == i) { 3201 Node *m = (ni >= nmm->req()) ? nmm->empty_memory() : nmm->in(ni); 3202 if (nmm->is_empty_memory(m)) { 3203 Node* result = find_inst_mem(mem, ni, orig_phis); 3204 if (_compile->failing()) { 3205 return; 3206 } 3207 nmm->set_memory_at(ni, result); 3208 } 3209 } 3210 } 3211 } 3212 // Find the rest of instances values 3213 for (uint ni = new_index_start; ni < new_index_end; ni++) { 3214 const TypeOopPtr *tinst = _compile->get_adr_type(ni)->isa_oopptr(); 3215 Node* result = step_through_mergemem(nmm, ni, tinst); 3216 if (result == nmm->base_memory()) { 3217 // Didn't find instance memory, search through general slice recursively. 3218 result = nmm->memory_at(_compile->get_general_index(ni)); 3219 result = find_inst_mem(result, ni, orig_phis); 3220 if (_compile->failing()) { 3221 return; 3222 } 3223 nmm->set_memory_at(ni, result); 3224 } 3225 } 3226 igvn->hash_insert(nmm); 3227 record_for_optimizer(nmm); 3228 } 3229 3230 // Phase 4: Update the inputs of non-instance memory Phis and 3231 // the Memory input of memnodes 3232 // First update the inputs of any non-instance Phi's from 3233 // which we split out an instance Phi. Note we don't have 3234 // to recursively process Phi's encounted on the input memory 3235 // chains as is done in split_memory_phi() since they will 3236 // also be processed here. 3237 for (int j = 0; j < orig_phis.length(); j++) { 3238 PhiNode *phi = orig_phis.at(j); 3239 int alias_idx = _compile->get_alias_index(phi->adr_type()); 3240 igvn->hash_delete(phi); 3241 for (uint i = 1; i < phi->req(); i++) { 3242 Node *mem = phi->in(i); 3243 Node *new_mem = find_inst_mem(mem, alias_idx, orig_phis); 3244 if (_compile->failing()) { 3245 return; 3246 } 3247 if (mem != new_mem) { 3248 phi->set_req(i, new_mem); 3249 } 3250 } 3251 igvn->hash_insert(phi); 3252 record_for_optimizer(phi); 3253 } 3254 3255 // Update the memory inputs of MemNodes with the value we computed 3256 // in Phase 2 and move stores memory users to corresponding memory slices. 3257 // Disable memory split verification code until the fix for 6984348. 3258 // Currently it produces false negative results since it does not cover all cases. 3259 #if 0 // ifdef ASSERT 3260 visited.Reset(); 3261 Node_Stack old_mems(arena, _compile->unique() >> 2); 3262 #endif 3263 for (uint i = 0; i < ideal_nodes.size(); i++) { 3264 Node* n = ideal_nodes.at(i); 3265 Node* nmem = get_map(n->_idx); 3266 assert(nmem != NULL, "sanity"); 3267 if (n->is_Mem()) { 3268 #if 0 // ifdef ASSERT 3269 Node* old_mem = n->in(MemNode::Memory); 3270 if (!visited.test_set(old_mem->_idx)) { 3271 old_mems.push(old_mem, old_mem->outcnt()); 3272 } 3273 #endif 3274 assert(n->in(MemNode::Memory) != nmem, "sanity"); 3275 if (!n->is_Load()) { 3276 // Move memory users of a store first. 3277 move_inst_mem(n, orig_phis); 3278 } 3279 // Now update memory input 3280 igvn->hash_delete(n); 3281 n->set_req(MemNode::Memory, nmem); 3282 igvn->hash_insert(n); 3283 record_for_optimizer(n); 3284 } else { 3285 assert(n->is_Allocate() || n->is_CheckCastPP() || 3286 n->is_AddP() || n->is_Phi(), "unknown node used for set_map()"); 3287 } 3288 } 3289 #if 0 // ifdef ASSERT 3290 // Verify that memory was split correctly 3291 while (old_mems.is_nonempty()) { 3292 Node* old_mem = old_mems.node(); 3293 uint old_cnt = old_mems.index(); 3294 old_mems.pop(); 3295 assert(old_cnt == old_mem->outcnt(), "old mem could be lost"); 3296 } 3297 #endif 3298 } 3299 3300 #ifndef PRODUCT 3301 static const char *node_type_names[] = { 3302 "UnknownType", 3303 "JavaObject", 3304 "LocalVar", 3305 "Field", 3306 "Arraycopy" 3307 }; 3308 3309 static const char *esc_names[] = { 3310 "UnknownEscape", 3311 "NoEscape", 3312 "ArgEscape", 3313 "GlobalEscape" 3314 }; 3315 3316 void PointsToNode::dump(bool print_state) const { 3317 NodeType nt = node_type(); 3318 tty->print("%s ", node_type_names[(int) nt]); 3319 if (print_state) { 3320 EscapeState es = escape_state(); 3321 EscapeState fields_es = fields_escape_state(); 3322 tty->print("%s(%s) ", esc_names[(int)es], esc_names[(int)fields_es]); 3323 if (nt == PointsToNode::JavaObject && !this->scalar_replaceable()) 3324 tty->print("NSR "); 3325 } 3326 if (is_Field()) { 3327 FieldNode* f = (FieldNode*)this; 3328 if (f->is_oop()) 3329 tty->print("oop "); 3330 if (f->offset() > 0) 3331 tty->print("+%d ", f->offset()); 3332 tty->print("("); 3333 for (BaseIterator i(f); i.has_next(); i.next()) { 3334 PointsToNode* b = i.get(); 3335 tty->print(" %d%s", b->idx(),(b->is_JavaObject() ? "P" : "")); 3336 } 3337 tty->print(" )"); 3338 } 3339 tty->print("["); 3340 for (EdgeIterator i(this); i.has_next(); i.next()) { 3341 PointsToNode* e = i.get(); 3342 tty->print(" %d%s%s", e->idx(),(e->is_JavaObject() ? "P" : (e->is_Field() ? "F" : "")), e->is_Arraycopy() ? "cp" : ""); 3343 } 3344 tty->print(" ["); 3345 for (UseIterator i(this); i.has_next(); i.next()) { 3346 PointsToNode* u = i.get(); 3347 bool is_base = false; 3348 if (PointsToNode::is_base_use(u)) { 3349 is_base = true; 3350 u = PointsToNode::get_use_node(u)->as_Field(); 3351 } 3352 tty->print(" %d%s%s", u->idx(), is_base ? "b" : "", u->is_Arraycopy() ? "cp" : ""); 3353 } 3354 tty->print(" ]] "); 3355 if (_node == NULL) 3356 tty->print_cr("<null>"); 3357 else 3358 _node->dump(); 3359 } 3360 3361 void ConnectionGraph::dump(GrowableArray<PointsToNode*>& ptnodes_worklist) { 3362 bool first = true; 3363 int ptnodes_length = ptnodes_worklist.length(); 3364 for (int i = 0; i < ptnodes_length; i++) { 3365 PointsToNode *ptn = ptnodes_worklist.at(i); 3366 if (ptn == NULL || !ptn->is_JavaObject()) 3367 continue; 3368 PointsToNode::EscapeState es = ptn->escape_state(); 3369 if ((es != PointsToNode::NoEscape) && !Verbose) { 3370 continue; 3371 } 3372 Node* n = ptn->ideal_node(); 3373 if (n->is_Allocate() || (n->is_CallStaticJava() && 3374 n->as_CallStaticJava()->is_boxing_method())) { 3375 if (first) { 3376 tty->cr(); 3377 tty->print("======== Connection graph for "); 3378 _compile->method()->print_short_name(); 3379 tty->cr(); 3380 first = false; 3381 } 3382 ptn->dump(); 3383 // Print all locals and fields which reference this allocation 3384 for (UseIterator j(ptn); j.has_next(); j.next()) { 3385 PointsToNode* use = j.get(); 3386 if (use->is_LocalVar()) { 3387 use->dump(Verbose); 3388 } else if (Verbose) { 3389 use->dump(); 3390 } 3391 } 3392 tty->cr(); 3393 } 3394 } 3395 } 3396 #endif