1 /* 2 * Copyright (c) 2005, 2018, 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 "memory/resourceArea.hpp" 31 #include "opto/c2compiler.hpp" 32 #include "opto/arraycopynode.hpp" 33 #include "opto/callnode.hpp" 34 #include "opto/cfgnode.hpp" 35 #include "opto/compile.hpp" 36 #include "opto/escape.hpp" 37 #include "opto/phaseX.hpp" 38 #include "opto/movenode.hpp" 39 #include "opto/rootnode.hpp" 40 #if INCLUDE_ALL_GCS 41 #include "gc/g1/g1ThreadLocalData.hpp" 42 #endif // INCLUDE_ALL_GCS 43 44 ConnectionGraph::ConnectionGraph(Compile * C, PhaseIterGVN *igvn) : 45 _nodes(C->comp_arena(), C->unique(), C->unique(), NULL), 46 _in_worklist(C->comp_arena()), 47 _next_pidx(0), 48 _collecting(true), 49 _verify(false), 50 _compile(C), 51 _igvn(igvn), 52 _node_map(C->comp_arena()) { 53 // Add unknown java object. 54 add_java_object(C->top(), PointsToNode::GlobalEscape); 55 phantom_obj = ptnode_adr(C->top()->_idx)->as_JavaObject(); 56 // Add ConP(#NULL) and ConN(#NULL) nodes. 57 Node* oop_null = igvn->zerocon(T_OBJECT); 58 assert(oop_null->_idx < nodes_size(), "should be created already"); 59 add_java_object(oop_null, PointsToNode::NoEscape); 60 null_obj = ptnode_adr(oop_null->_idx)->as_JavaObject(); 61 if (UseCompressedOops) { 62 Node* noop_null = igvn->zerocon(T_NARROWOOP); 63 assert(noop_null->_idx < nodes_size(), "should be created already"); 64 map_ideal_node(noop_null, null_obj); 65 } 66 _pcmp_neq = NULL; // Should be initialized 67 _pcmp_eq = NULL; 68 } 69 70 bool ConnectionGraph::has_candidates(Compile *C) { 71 // EA brings benefits only when the code has allocations and/or locks which 72 // are represented by ideal Macro nodes. 73 int cnt = C->macro_count(); 74 for (int i = 0; i < cnt; i++) { 75 Node *n = C->macro_node(i); 76 if (n->is_Allocate()) 77 return true; 78 if (n->is_Lock()) { 79 Node* obj = n->as_Lock()->obj_node()->uncast(); 80 if (!(obj->is_Parm() || obj->is_Con())) 81 return true; 82 } 83 if (n->is_CallStaticJava() && 84 n->as_CallStaticJava()->is_boxing_method()) { 85 return true; 86 } 87 } 88 return false; 89 } 90 91 void ConnectionGraph::do_analysis(Compile *C, PhaseIterGVN *igvn) { 92 Compile::TracePhase tp("escapeAnalysis", &Phase::timers[Phase::_t_escapeAnalysis]); 93 ResourceMark rm; 94 95 // Add ConP#NULL and ConN#NULL nodes before ConnectionGraph construction 96 // to create space for them in ConnectionGraph::_nodes[]. 97 Node* oop_null = igvn->zerocon(T_OBJECT); 98 Node* noop_null = igvn->zerocon(T_NARROWOOP); 99 ConnectionGraph* congraph = new(C->comp_arena()) ConnectionGraph(C, igvn); 100 // Perform escape analysis 101 if (congraph->compute_escape()) { 102 // There are non escaping objects. 103 C->set_congraph(congraph); 104 } 105 // Cleanup. 106 if (oop_null->outcnt() == 0) 107 igvn->hash_delete(oop_null); 108 if (noop_null->outcnt() == 0) 109 igvn->hash_delete(noop_null); 110 } 111 112 bool ConnectionGraph::compute_escape() { 113 Compile* C = _compile; 114 PhaseGVN* igvn = _igvn; 115 116 // Worklists used by EA. 117 Unique_Node_List delayed_worklist; 118 GrowableArray<Node*> alloc_worklist; 119 GrowableArray<Node*> ptr_cmp_worklist; 120 GrowableArray<Node*> storestore_worklist; 121 GrowableArray<ArrayCopyNode*> arraycopy_worklist; 122 GrowableArray<PointsToNode*> ptnodes_worklist; 123 GrowableArray<JavaObjectNode*> java_objects_worklist; 124 GrowableArray<JavaObjectNode*> non_escaped_worklist; 125 GrowableArray<FieldNode*> oop_fields_worklist; 126 DEBUG_ONLY( GrowableArray<Node*> addp_worklist; ) 127 128 { Compile::TracePhase tp("connectionGraph", &Phase::timers[Phase::_t_connectionGraph]); 129 130 // 1. Populate Connection Graph (CG) with PointsTo nodes. 131 ideal_nodes.map(C->live_nodes(), NULL); // preallocate space 132 // Initialize worklist 133 if (C->root() != NULL) { 134 ideal_nodes.push(C->root()); 135 } 136 // Processed ideal nodes are unique on ideal_nodes list 137 // but several ideal nodes are mapped to the phantom_obj. 138 // To avoid duplicated entries on the following worklists 139 // add the phantom_obj only once to them. 140 ptnodes_worklist.append(phantom_obj); 141 java_objects_worklist.append(phantom_obj); 142 for( uint next = 0; next < ideal_nodes.size(); ++next ) { 143 Node* n = ideal_nodes.at(next); 144 // Create PointsTo nodes and add them to Connection Graph. Called 145 // only once per ideal node since ideal_nodes is Unique_Node list. 146 add_node_to_connection_graph(n, &delayed_worklist); 147 PointsToNode* ptn = ptnode_adr(n->_idx); 148 if (ptn != NULL && ptn != phantom_obj) { 149 ptnodes_worklist.append(ptn); 150 if (ptn->is_JavaObject()) { 151 java_objects_worklist.append(ptn->as_JavaObject()); 152 if ((n->is_Allocate() || n->is_CallStaticJava()) && 153 (ptn->escape_state() < PointsToNode::GlobalEscape)) { 154 // Only allocations and java static calls results are interesting. 155 non_escaped_worklist.append(ptn->as_JavaObject()); 156 } 157 } else if (ptn->is_Field() && ptn->as_Field()->is_oop()) { 158 oop_fields_worklist.append(ptn->as_Field()); 159 } 160 } 161 if (n->is_MergeMem()) { 162 // Collect all MergeMem nodes to add memory slices for 163 // scalar replaceable objects in split_unique_types(). 164 _mergemem_worklist.append(n->as_MergeMem()); 165 } else if (OptimizePtrCompare && n->is_Cmp() && 166 (n->Opcode() == Op_CmpP || n->Opcode() == Op_CmpN)) { 167 // Collect compare pointers nodes. 168 ptr_cmp_worklist.append(n); 169 } else if (n->is_MemBarStoreStore()) { 170 // Collect all MemBarStoreStore nodes so that depending on the 171 // escape status of the associated Allocate node some of them 172 // may be eliminated. 173 storestore_worklist.append(n); 174 } else if (n->is_MemBar() && (n->Opcode() == Op_MemBarRelease) && 175 (n->req() > MemBarNode::Precedent)) { 176 record_for_optimizer(n); 177 #ifdef ASSERT 178 } else if (n->is_AddP()) { 179 // Collect address nodes for graph verification. 180 addp_worklist.append(n); 181 #endif 182 } else if (n->is_ArrayCopy()) { 183 // Keep a list of ArrayCopy nodes so if one of its input is non 184 // escaping, we can record a unique type 185 arraycopy_worklist.append(n->as_ArrayCopy()); 186 } 187 for (DUIterator_Fast imax, i = n->fast_outs(imax); i < imax; i++) { 188 Node* m = n->fast_out(i); // Get user 189 ideal_nodes.push(m); 190 } 191 } 192 if (non_escaped_worklist.length() == 0) { 193 _collecting = false; 194 return false; // Nothing to do. 195 } 196 // Add final simple edges to graph. 197 while(delayed_worklist.size() > 0) { 198 Node* n = delayed_worklist.pop(); 199 add_final_edges(n); 200 } 201 int ptnodes_length = ptnodes_worklist.length(); 202 203 #ifdef ASSERT 204 if (VerifyConnectionGraph) { 205 // Verify that no new simple edges could be created and all 206 // local vars has edges. 207 _verify = true; 208 for (int next = 0; next < ptnodes_length; ++next) { 209 PointsToNode* ptn = ptnodes_worklist.at(next); 210 add_final_edges(ptn->ideal_node()); 211 if (ptn->is_LocalVar() && ptn->edge_count() == 0) { 212 ptn->dump(); 213 assert(ptn->as_LocalVar()->edge_count() > 0, "sanity"); 214 } 215 } 216 _verify = false; 217 } 218 #endif 219 // Bytecode analyzer BCEscapeAnalyzer, used for Call nodes 220 // processing, calls to CI to resolve symbols (types, fields, methods) 221 // referenced in bytecode. During symbol resolution VM may throw 222 // an exception which CI cleans and converts to compilation failure. 223 if (C->failing()) return false; 224 225 // 2. Finish Graph construction by propagating references to all 226 // java objects through graph. 227 if (!complete_connection_graph(ptnodes_worklist, non_escaped_worklist, 228 java_objects_worklist, oop_fields_worklist)) { 229 // All objects escaped or hit time or iterations limits. 230 _collecting = false; 231 return false; 232 } 233 234 // 3. Adjust scalar_replaceable state of nonescaping objects and push 235 // scalar replaceable allocations on alloc_worklist for processing 236 // in split_unique_types(). 237 int non_escaped_length = non_escaped_worklist.length(); 238 for (int next = 0; next < non_escaped_length; next++) { 239 JavaObjectNode* ptn = non_escaped_worklist.at(next); 240 bool noescape = (ptn->escape_state() == PointsToNode::NoEscape); 241 Node* n = ptn->ideal_node(); 242 if (n->is_Allocate()) { 243 n->as_Allocate()->_is_non_escaping = noescape; 244 } 245 if (n->is_CallStaticJava()) { 246 n->as_CallStaticJava()->_is_non_escaping = noescape; 247 } 248 if (noescape && ptn->scalar_replaceable()) { 249 adjust_scalar_replaceable_state(ptn); 250 if (ptn->scalar_replaceable()) { 251 alloc_worklist.append(ptn->ideal_node()); 252 } 253 } 254 } 255 256 #ifdef ASSERT 257 if (VerifyConnectionGraph) { 258 // Verify that graph is complete - no new edges could be added or needed. 259 verify_connection_graph(ptnodes_worklist, non_escaped_worklist, 260 java_objects_worklist, addp_worklist); 261 } 262 assert(C->unique() == nodes_size(), "no new ideal nodes should be added during ConnectionGraph build"); 263 assert(null_obj->escape_state() == PointsToNode::NoEscape && 264 null_obj->edge_count() == 0 && 265 !null_obj->arraycopy_src() && 266 !null_obj->arraycopy_dst(), "sanity"); 267 #endif 268 269 _collecting = false; 270 271 } // TracePhase t3("connectionGraph") 272 273 // 4. Optimize ideal graph based on EA information. 274 bool has_non_escaping_obj = (non_escaped_worklist.length() > 0); 275 if (has_non_escaping_obj) { 276 optimize_ideal_graph(ptr_cmp_worklist, storestore_worklist); 277 } 278 279 #ifndef PRODUCT 280 if (PrintEscapeAnalysis) { 281 dump(ptnodes_worklist); // Dump ConnectionGraph 282 } 283 #endif 284 285 bool has_scalar_replaceable_candidates = (alloc_worklist.length() > 0); 286 #ifdef ASSERT 287 if (VerifyConnectionGraph) { 288 int alloc_length = alloc_worklist.length(); 289 for (int next = 0; next < alloc_length; ++next) { 290 Node* n = alloc_worklist.at(next); 291 PointsToNode* ptn = ptnode_adr(n->_idx); 292 assert(ptn->escape_state() == PointsToNode::NoEscape && ptn->scalar_replaceable(), "sanity"); 293 } 294 } 295 #endif 296 297 // 5. Separate memory graph for scalar replaceable allcations. 298 if (has_scalar_replaceable_candidates && 299 C->AliasLevel() >= 3 && EliminateAllocations) { 300 // Now use the escape information to create unique types for 301 // scalar replaceable objects. 302 split_unique_types(alloc_worklist, arraycopy_worklist); 303 if (C->failing()) return false; 304 C->print_method(PHASE_AFTER_EA, 2); 305 306 #ifdef ASSERT 307 } else if (Verbose && (PrintEscapeAnalysis || PrintEliminateAllocations)) { 308 tty->print("=== No allocations eliminated for "); 309 C->method()->print_short_name(); 310 if(!EliminateAllocations) { 311 tty->print(" since EliminateAllocations is off ==="); 312 } else if(!has_scalar_replaceable_candidates) { 313 tty->print(" since there are no scalar replaceable candidates ==="); 314 } else if(C->AliasLevel() < 3) { 315 tty->print(" since AliasLevel < 3 ==="); 316 } 317 tty->cr(); 318 #endif 319 } 320 return has_non_escaping_obj; 321 } 322 323 // Utility function for nodes that load an object 324 void ConnectionGraph::add_objload_to_connection_graph(Node *n, Unique_Node_List *delayed_worklist) { 325 // Using isa_ptr() instead of isa_oopptr() for LoadP and Phi because 326 // ThreadLocal has RawPtr type. 327 const Type* t = _igvn->type(n); 328 if (t->make_ptr() != NULL) { 329 Node* adr = n->in(MemNode::Address); 330 #ifdef ASSERT 331 if (!adr->is_AddP()) { 332 assert(_igvn->type(adr)->isa_rawptr(), "sanity"); 333 } else { 334 assert((ptnode_adr(adr->_idx) == NULL || 335 ptnode_adr(adr->_idx)->as_Field()->is_oop()), "sanity"); 336 } 337 #endif 338 add_local_var_and_edge(n, PointsToNode::NoEscape, 339 adr, delayed_worklist); 340 } 341 } 342 343 // Populate Connection Graph with PointsTo nodes and create simple 344 // connection graph edges. 345 void ConnectionGraph::add_node_to_connection_graph(Node *n, Unique_Node_List *delayed_worklist) { 346 assert(!_verify, "this method should not be called for verification"); 347 PhaseGVN* igvn = _igvn; 348 uint n_idx = n->_idx; 349 PointsToNode* n_ptn = ptnode_adr(n_idx); 350 if (n_ptn != NULL) 351 return; // No need to redefine PointsTo node during first iteration. 352 353 if (n->is_Call()) { 354 // Arguments to allocation and locking don't escape. 355 if (n->is_AbstractLock()) { 356 // Put Lock and Unlock nodes on IGVN worklist to process them during 357 // first IGVN optimization when escape information is still available. 358 record_for_optimizer(n); 359 } else if (n->is_Allocate()) { 360 add_call_node(n->as_Call()); 361 record_for_optimizer(n); 362 } else { 363 if (n->is_CallStaticJava()) { 364 const char* name = n->as_CallStaticJava()->_name; 365 if (name != NULL && strcmp(name, "uncommon_trap") == 0) 366 return; // Skip uncommon traps 367 } 368 // Don't mark as processed since call's arguments have to be processed. 369 delayed_worklist->push(n); 370 // Check if a call returns an object. 371 if ((n->as_Call()->returns_pointer() && 372 n->as_Call()->proj_out_or_null(TypeFunc::Parms) != NULL) || 373 (n->is_CallStaticJava() && 374 n->as_CallStaticJava()->is_boxing_method())) { 375 add_call_node(n->as_Call()); 376 } 377 } 378 return; 379 } 380 // Put this check here to process call arguments since some call nodes 381 // point to phantom_obj. 382 if (n_ptn == phantom_obj || n_ptn == null_obj) 383 return; // Skip predefined nodes. 384 385 int opcode = n->Opcode(); 386 switch (opcode) { 387 case Op_AddP: { 388 Node* base = get_addp_base(n); 389 PointsToNode* ptn_base = ptnode_adr(base->_idx); 390 // Field nodes are created for all field types. They are used in 391 // adjust_scalar_replaceable_state() and split_unique_types(). 392 // Note, non-oop fields will have only base edges in Connection 393 // Graph because such fields are not used for oop loads and stores. 394 int offset = address_offset(n, igvn); 395 add_field(n, PointsToNode::NoEscape, offset); 396 if (ptn_base == NULL) { 397 delayed_worklist->push(n); // Process it later. 398 } else { 399 n_ptn = ptnode_adr(n_idx); 400 add_base(n_ptn->as_Field(), ptn_base); 401 } 402 break; 403 } 404 case Op_CastX2P: { 405 map_ideal_node(n, phantom_obj); 406 break; 407 } 408 case Op_CastPP: 409 case Op_CheckCastPP: 410 case Op_EncodeP: 411 case Op_DecodeN: 412 case Op_EncodePKlass: 413 case Op_DecodeNKlass: { 414 add_local_var_and_edge(n, PointsToNode::NoEscape, 415 n->in(1), delayed_worklist); 416 break; 417 } 418 case Op_CMoveP: { 419 add_local_var(n, PointsToNode::NoEscape); 420 // Do not add edges during first iteration because some could be 421 // not defined yet. 422 delayed_worklist->push(n); 423 break; 424 } 425 case Op_ConP: 426 case Op_ConN: 427 case Op_ConNKlass: { 428 // assume all oop constants globally escape except for null 429 PointsToNode::EscapeState es; 430 const Type* t = igvn->type(n); 431 if (t == TypePtr::NULL_PTR || t == TypeNarrowOop::NULL_PTR) { 432 es = PointsToNode::NoEscape; 433 } else { 434 es = PointsToNode::GlobalEscape; 435 } 436 add_java_object(n, es); 437 break; 438 } 439 case Op_CreateEx: { 440 // assume that all exception objects globally escape 441 map_ideal_node(n, phantom_obj); 442 break; 443 } 444 case Op_LoadKlass: 445 case Op_LoadNKlass: { 446 // Unknown class is loaded 447 map_ideal_node(n, phantom_obj); 448 break; 449 } 450 case Op_LoadP: 451 case Op_LoadN: 452 case Op_LoadPLocked: { 453 add_objload_to_connection_graph(n, delayed_worklist); 454 break; 455 } 456 case Op_Parm: { 457 map_ideal_node(n, phantom_obj); 458 break; 459 } 460 case Op_PartialSubtypeCheck: { 461 // Produces Null or notNull and is used in only in CmpP so 462 // phantom_obj could be used. 463 map_ideal_node(n, phantom_obj); // Result is unknown 464 break; 465 } 466 case Op_Phi: { 467 // Using isa_ptr() instead of isa_oopptr() for LoadP and Phi because 468 // ThreadLocal has RawPtr type. 469 const Type* t = n->as_Phi()->type(); 470 if (t->make_ptr() != NULL) { 471 add_local_var(n, PointsToNode::NoEscape); 472 // Do not add edges during first iteration because some could be 473 // not defined yet. 474 delayed_worklist->push(n); 475 } 476 break; 477 } 478 case Op_Proj: { 479 // we are only interested in the oop result projection from a call 480 if (n->as_Proj()->_con == TypeFunc::Parms && n->in(0)->is_Call() && 481 n->in(0)->as_Call()->returns_pointer()) { 482 add_local_var_and_edge(n, PointsToNode::NoEscape, 483 n->in(0), delayed_worklist); 484 } 485 break; 486 } 487 case Op_Rethrow: // Exception object escapes 488 case Op_Return: { 489 if (n->req() > TypeFunc::Parms && 490 igvn->type(n->in(TypeFunc::Parms))->isa_oopptr()) { 491 // Treat Return value as LocalVar with GlobalEscape escape state. 492 add_local_var_and_edge(n, PointsToNode::GlobalEscape, 493 n->in(TypeFunc::Parms), delayed_worklist); 494 } 495 break; 496 } 497 case Op_CompareAndExchangeP: 498 case Op_CompareAndExchangeN: 499 case Op_GetAndSetP: 500 case Op_GetAndSetN: { 501 add_objload_to_connection_graph(n, delayed_worklist); 502 // fallthrough 503 } 504 case Op_StoreP: 505 case Op_StoreN: 506 case Op_StoreNKlass: 507 case Op_StorePConditional: 508 case Op_WeakCompareAndSwapP: 509 case Op_WeakCompareAndSwapN: 510 case Op_CompareAndSwapP: 511 case Op_CompareAndSwapN: { 512 Node* adr = n->in(MemNode::Address); 513 const Type *adr_type = igvn->type(adr); 514 adr_type = adr_type->make_ptr(); 515 if (adr_type == NULL) { 516 break; // skip dead nodes 517 } 518 if ( adr_type->isa_oopptr() 519 || ( (opcode == Op_StoreP || opcode == Op_StoreN || opcode == Op_StoreNKlass) 520 && adr_type == TypeRawPtr::NOTNULL 521 && adr->in(AddPNode::Address)->is_Proj() 522 && adr->in(AddPNode::Address)->in(0)->is_Allocate())) { 523 delayed_worklist->push(n); // Process it later. 524 #ifdef ASSERT 525 assert(adr->is_AddP(), "expecting an AddP"); 526 if (adr_type == TypeRawPtr::NOTNULL) { 527 // Verify a raw address for a store captured by Initialize node. 528 int offs = (int)igvn->find_intptr_t_con(adr->in(AddPNode::Offset), Type::OffsetBot); 529 assert(offs != Type::OffsetBot, "offset must be a constant"); 530 } 531 #endif 532 } else { 533 // Ignore copy the displaced header to the BoxNode (OSR compilation). 534 if (adr->is_BoxLock()) 535 break; 536 // Stored value escapes in unsafe access. 537 if ((opcode == Op_StoreP) && adr_type->isa_rawptr()) { 538 // Pointer stores in G1 barriers looks like unsafe access. 539 // Ignore such stores to be able scalar replace non-escaping 540 // allocations. 541 if (UseG1GC && adr->is_AddP()) { 542 Node* base = get_addp_base(adr); 543 if (base->Opcode() == Op_LoadP && 544 base->in(MemNode::Address)->is_AddP()) { 545 adr = base->in(MemNode::Address); 546 Node* tls = get_addp_base(adr); 547 if (tls->Opcode() == Op_ThreadLocal) { 548 int offs = (int)igvn->find_intptr_t_con(adr->in(AddPNode::Offset), Type::OffsetBot); 549 if (offs == in_bytes(G1ThreadLocalData::satb_mark_queue_buffer_offset())) { 550 break; // G1 pre barrier previous oop value store. 551 } 552 if (offs == in_bytes(G1ThreadLocalData::dirty_card_queue_buffer_offset())) { 553 break; // G1 post barrier card address store. 554 } 555 } 556 } 557 } 558 delayed_worklist->push(n); // Process unsafe access later. 559 break; 560 } 561 #ifdef ASSERT 562 n->dump(1); 563 assert(false, "not unsafe or G1 barrier raw StoreP"); 564 #endif 565 } 566 break; 567 } 568 case Op_AryEq: 569 case Op_HasNegatives: 570 case Op_StrComp: 571 case Op_StrEquals: 572 case Op_StrIndexOf: 573 case Op_StrIndexOfChar: 574 case Op_StrInflatedCopy: 575 case Op_StrCompressedCopy: 576 case Op_EncodeISOArray: { 577 add_local_var(n, PointsToNode::ArgEscape); 578 delayed_worklist->push(n); // Process it later. 579 break; 580 } 581 case Op_ThreadLocal: { 582 add_java_object(n, PointsToNode::ArgEscape); 583 break; 584 } 585 default: 586 ; // Do nothing for nodes not related to EA. 587 } 588 return; 589 } 590 591 #ifdef ASSERT 592 #define ELSE_FAIL(name) \ 593 /* Should not be called for not pointer type. */ \ 594 n->dump(1); \ 595 assert(false, name); \ 596 break; 597 #else 598 #define ELSE_FAIL(name) \ 599 break; 600 #endif 601 602 // Add final simple edges to graph. 603 void ConnectionGraph::add_final_edges(Node *n) { 604 PointsToNode* n_ptn = ptnode_adr(n->_idx); 605 #ifdef ASSERT 606 if (_verify && n_ptn->is_JavaObject()) 607 return; // This method does not change graph for JavaObject. 608 #endif 609 610 if (n->is_Call()) { 611 process_call_arguments(n->as_Call()); 612 return; 613 } 614 assert(n->is_Store() || n->is_LoadStore() || 615 (n_ptn != NULL) && (n_ptn->ideal_node() != NULL), 616 "node should be registered already"); 617 int opcode = n->Opcode(); 618 switch (opcode) { 619 case Op_AddP: { 620 Node* base = get_addp_base(n); 621 PointsToNode* ptn_base = ptnode_adr(base->_idx); 622 assert(ptn_base != NULL, "field's base should be registered"); 623 add_base(n_ptn->as_Field(), ptn_base); 624 break; 625 } 626 case Op_CastPP: 627 case Op_CheckCastPP: 628 case Op_EncodeP: 629 case Op_DecodeN: 630 case Op_EncodePKlass: 631 case Op_DecodeNKlass: { 632 add_local_var_and_edge(n, PointsToNode::NoEscape, 633 n->in(1), NULL); 634 break; 635 } 636 case Op_CMoveP: { 637 for (uint i = CMoveNode::IfFalse; i < n->req(); i++) { 638 Node* in = n->in(i); 639 if (in == NULL) 640 continue; // ignore NULL 641 Node* uncast_in = in->uncast(); 642 if (uncast_in->is_top() || uncast_in == n) 643 continue; // ignore top or inputs which go back this node 644 PointsToNode* ptn = ptnode_adr(in->_idx); 645 assert(ptn != NULL, "node should be registered"); 646 add_edge(n_ptn, ptn); 647 } 648 break; 649 } 650 case Op_LoadP: 651 case Op_LoadN: 652 case Op_LoadPLocked: { 653 // Using isa_ptr() instead of isa_oopptr() for LoadP and Phi because 654 // ThreadLocal has RawPtr type. 655 const Type* t = _igvn->type(n); 656 if (t->make_ptr() != NULL) { 657 Node* adr = n->in(MemNode::Address); 658 add_local_var_and_edge(n, PointsToNode::NoEscape, adr, NULL); 659 break; 660 } 661 ELSE_FAIL("Op_LoadP"); 662 } 663 case Op_Phi: { 664 // Using isa_ptr() instead of isa_oopptr() for LoadP and Phi because 665 // ThreadLocal has RawPtr type. 666 const Type* t = n->as_Phi()->type(); 667 if (t->make_ptr() != NULL) { 668 for (uint i = 1; i < n->req(); i++) { 669 Node* in = n->in(i); 670 if (in == NULL) 671 continue; // ignore NULL 672 Node* uncast_in = in->uncast(); 673 if (uncast_in->is_top() || uncast_in == n) 674 continue; // ignore top or inputs which go back this node 675 PointsToNode* ptn = ptnode_adr(in->_idx); 676 assert(ptn != NULL, "node should be registered"); 677 add_edge(n_ptn, ptn); 678 } 679 break; 680 } 681 ELSE_FAIL("Op_Phi"); 682 } 683 case Op_Proj: { 684 // we are only interested in the oop result projection from a call 685 if (n->as_Proj()->_con == TypeFunc::Parms && n->in(0)->is_Call() && 686 n->in(0)->as_Call()->returns_pointer()) { 687 add_local_var_and_edge(n, PointsToNode::NoEscape, n->in(0), NULL); 688 break; 689 } 690 ELSE_FAIL("Op_Proj"); 691 } 692 case Op_Rethrow: // Exception object escapes 693 case Op_Return: { 694 if (n->req() > TypeFunc::Parms && 695 _igvn->type(n->in(TypeFunc::Parms))->isa_oopptr()) { 696 // Treat Return value as LocalVar with GlobalEscape escape state. 697 add_local_var_and_edge(n, PointsToNode::GlobalEscape, 698 n->in(TypeFunc::Parms), NULL); 699 break; 700 } 701 ELSE_FAIL("Op_Return"); 702 } 703 case Op_StoreP: 704 case Op_StoreN: 705 case Op_StoreNKlass: 706 case Op_StorePConditional: 707 case Op_CompareAndExchangeP: 708 case Op_CompareAndExchangeN: 709 case Op_CompareAndSwapP: 710 case Op_CompareAndSwapN: 711 case Op_WeakCompareAndSwapP: 712 case Op_WeakCompareAndSwapN: 713 case Op_GetAndSetP: 714 case Op_GetAndSetN: { 715 Node* adr = n->in(MemNode::Address); 716 const Type *adr_type = _igvn->type(adr); 717 adr_type = adr_type->make_ptr(); 718 #ifdef ASSERT 719 if (adr_type == NULL) { 720 n->dump(1); 721 assert(adr_type != NULL, "dead node should not be on list"); 722 break; 723 } 724 #endif 725 if (opcode == Op_GetAndSetP || opcode == Op_GetAndSetN || 726 opcode == Op_CompareAndExchangeN || opcode == Op_CompareAndExchangeP) { 727 add_local_var_and_edge(n, PointsToNode::NoEscape, adr, NULL); 728 } 729 if ( adr_type->isa_oopptr() 730 || ( (opcode == Op_StoreP || opcode == Op_StoreN || opcode == Op_StoreNKlass) 731 && adr_type == TypeRawPtr::NOTNULL 732 && adr->in(AddPNode::Address)->is_Proj() 733 && adr->in(AddPNode::Address)->in(0)->is_Allocate())) { 734 // Point Address to Value 735 PointsToNode* adr_ptn = ptnode_adr(adr->_idx); 736 assert(adr_ptn != NULL && 737 adr_ptn->as_Field()->is_oop(), "node should be registered"); 738 Node *val = n->in(MemNode::ValueIn); 739 PointsToNode* ptn = ptnode_adr(val->_idx); 740 assert(ptn != NULL, "node should be registered"); 741 add_edge(adr_ptn, ptn); 742 break; 743 } else if ((opcode == Op_StoreP) && adr_type->isa_rawptr()) { 744 // Stored value escapes in unsafe access. 745 Node *val = n->in(MemNode::ValueIn); 746 PointsToNode* ptn = ptnode_adr(val->_idx); 747 assert(ptn != NULL, "node should be registered"); 748 set_escape_state(ptn, PointsToNode::GlobalEscape); 749 // Add edge to object for unsafe access with offset. 750 PointsToNode* adr_ptn = ptnode_adr(adr->_idx); 751 assert(adr_ptn != NULL, "node should be registered"); 752 if (adr_ptn->is_Field()) { 753 assert(adr_ptn->as_Field()->is_oop(), "should be oop field"); 754 add_edge(adr_ptn, ptn); 755 } 756 break; 757 } 758 ELSE_FAIL("Op_StoreP"); 759 } 760 case Op_AryEq: 761 case Op_HasNegatives: 762 case Op_StrComp: 763 case Op_StrEquals: 764 case Op_StrIndexOf: 765 case Op_StrIndexOfChar: 766 case Op_StrInflatedCopy: 767 case Op_StrCompressedCopy: 768 case Op_EncodeISOArray: { 769 // char[]/byte[] arrays passed to string intrinsic do not escape but 770 // they are not scalar replaceable. Adjust escape state for them. 771 // Start from in(2) edge since in(1) is memory edge. 772 for (uint i = 2; i < n->req(); i++) { 773 Node* adr = n->in(i); 774 const Type* at = _igvn->type(adr); 775 if (!adr->is_top() && at->isa_ptr()) { 776 assert(at == Type::TOP || at == TypePtr::NULL_PTR || 777 at->isa_ptr() != NULL, "expecting a pointer"); 778 if (adr->is_AddP()) { 779 adr = get_addp_base(adr); 780 } 781 PointsToNode* ptn = ptnode_adr(adr->_idx); 782 assert(ptn != NULL, "node should be registered"); 783 add_edge(n_ptn, ptn); 784 } 785 } 786 break; 787 } 788 default: { 789 // This method should be called only for EA specific nodes which may 790 // miss some edges when they were created. 791 #ifdef ASSERT 792 n->dump(1); 793 #endif 794 guarantee(false, "unknown node"); 795 } 796 } 797 return; 798 } 799 800 void ConnectionGraph::add_call_node(CallNode* call) { 801 assert(call->returns_pointer(), "only for call which returns pointer"); 802 uint call_idx = call->_idx; 803 if (call->is_Allocate()) { 804 Node* k = call->in(AllocateNode::KlassNode); 805 const TypeKlassPtr* kt = k->bottom_type()->isa_klassptr(); 806 assert(kt != NULL, "TypeKlassPtr required."); 807 ciKlass* cik = kt->klass(); 808 PointsToNode::EscapeState es = PointsToNode::NoEscape; 809 bool scalar_replaceable = true; 810 if (call->is_AllocateArray()) { 811 if (!cik->is_array_klass()) { // StressReflectiveCode 812 es = PointsToNode::GlobalEscape; 813 } else { 814 int length = call->in(AllocateNode::ALength)->find_int_con(-1); 815 if (length < 0 || length > EliminateAllocationArraySizeLimit) { 816 // Not scalar replaceable if the length is not constant or too big. 817 scalar_replaceable = false; 818 } 819 } 820 } else { // Allocate instance 821 if (cik->is_subclass_of(_compile->env()->Thread_klass()) || 822 cik->is_subclass_of(_compile->env()->Reference_klass()) || 823 !cik->is_instance_klass() || // StressReflectiveCode 824 !cik->as_instance_klass()->can_be_instantiated() || 825 cik->as_instance_klass()->has_finalizer()) { 826 es = PointsToNode::GlobalEscape; 827 } 828 } 829 add_java_object(call, es); 830 PointsToNode* ptn = ptnode_adr(call_idx); 831 if (!scalar_replaceable && ptn->scalar_replaceable()) { 832 ptn->set_scalar_replaceable(false); 833 } 834 } else if (call->is_CallStaticJava()) { 835 // Call nodes could be different types: 836 // 837 // 1. CallDynamicJavaNode (what happened during call is unknown): 838 // 839 // - mapped to GlobalEscape JavaObject node if oop is returned; 840 // 841 // - all oop arguments are escaping globally; 842 // 843 // 2. CallStaticJavaNode (execute bytecode analysis if possible): 844 // 845 // - the same as CallDynamicJavaNode if can't do bytecode analysis; 846 // 847 // - mapped to GlobalEscape JavaObject node if unknown oop is returned; 848 // - mapped to NoEscape JavaObject node if non-escaping object allocated 849 // during call is returned; 850 // - mapped to ArgEscape LocalVar node pointed to object arguments 851 // which are returned and does not escape during call; 852 // 853 // - oop arguments escaping status is defined by bytecode analysis; 854 // 855 // For a static call, we know exactly what method is being called. 856 // Use bytecode estimator to record whether the call's return value escapes. 857 ciMethod* meth = call->as_CallJava()->method(); 858 if (meth == NULL) { 859 const char* name = call->as_CallStaticJava()->_name; 860 assert(strncmp(name, "_multianewarray", 15) == 0, "TODO: add failed case check"); 861 // Returns a newly allocated unescaped object. 862 add_java_object(call, PointsToNode::NoEscape); 863 ptnode_adr(call_idx)->set_scalar_replaceable(false); 864 } else if (meth->is_boxing_method()) { 865 // Returns boxing object 866 PointsToNode::EscapeState es; 867 vmIntrinsics::ID intr = meth->intrinsic_id(); 868 if (intr == vmIntrinsics::_floatValue || intr == vmIntrinsics::_doubleValue) { 869 // It does not escape if object is always allocated. 870 es = PointsToNode::NoEscape; 871 } else { 872 // It escapes globally if object could be loaded from cache. 873 es = PointsToNode::GlobalEscape; 874 } 875 add_java_object(call, es); 876 } else { 877 BCEscapeAnalyzer* call_analyzer = meth->get_bcea(); 878 call_analyzer->copy_dependencies(_compile->dependencies()); 879 if (call_analyzer->is_return_allocated()) { 880 // Returns a newly allocated unescaped object, simply 881 // update dependency information. 882 // Mark it as NoEscape so that objects referenced by 883 // it's fields will be marked as NoEscape at least. 884 add_java_object(call, PointsToNode::NoEscape); 885 ptnode_adr(call_idx)->set_scalar_replaceable(false); 886 } else { 887 // Determine whether any arguments are returned. 888 const TypeTuple* d = call->tf()->domain(); 889 bool ret_arg = false; 890 for (uint i = TypeFunc::Parms; i < d->cnt(); i++) { 891 if (d->field_at(i)->isa_ptr() != NULL && 892 call_analyzer->is_arg_returned(i - TypeFunc::Parms)) { 893 ret_arg = true; 894 break; 895 } 896 } 897 if (ret_arg) { 898 add_local_var(call, PointsToNode::ArgEscape); 899 } else { 900 // Returns unknown object. 901 map_ideal_node(call, phantom_obj); 902 } 903 } 904 } 905 } else { 906 // An other type of call, assume the worst case: 907 // returned value is unknown and globally escapes. 908 assert(call->Opcode() == Op_CallDynamicJava, "add failed case check"); 909 map_ideal_node(call, phantom_obj); 910 } 911 } 912 913 void ConnectionGraph::process_call_arguments(CallNode *call) { 914 bool is_arraycopy = false; 915 switch (call->Opcode()) { 916 #ifdef ASSERT 917 case Op_Allocate: 918 case Op_AllocateArray: 919 case Op_Lock: 920 case Op_Unlock: 921 assert(false, "should be done already"); 922 break; 923 #endif 924 case Op_ArrayCopy: 925 case Op_CallLeafNoFP: 926 // Most array copies are ArrayCopy nodes at this point but there 927 // are still a few direct calls to the copy subroutines (See 928 // PhaseStringOpts::copy_string()) 929 is_arraycopy = (call->Opcode() == Op_ArrayCopy) || 930 call->as_CallLeaf()->is_call_to_arraycopystub(); 931 // fall through 932 case Op_CallLeaf: { 933 // Stub calls, objects do not escape but they are not scale replaceable. 934 // Adjust escape state for outgoing arguments. 935 const TypeTuple * d = call->tf()->domain(); 936 bool src_has_oops = false; 937 for (uint i = TypeFunc::Parms; i < d->cnt(); i++) { 938 const Type* at = d->field_at(i); 939 Node *arg = call->in(i); 940 if (arg == NULL) { 941 continue; 942 } 943 const Type *aat = _igvn->type(arg); 944 if (arg->is_top() || !at->isa_ptr() || !aat->isa_ptr()) 945 continue; 946 if (arg->is_AddP()) { 947 // 948 // The inline_native_clone() case when the arraycopy stub is called 949 // after the allocation before Initialize and CheckCastPP nodes. 950 // Or normal arraycopy for object arrays case. 951 // 952 // Set AddP's base (Allocate) as not scalar replaceable since 953 // pointer to the base (with offset) is passed as argument. 954 // 955 arg = get_addp_base(arg); 956 } 957 PointsToNode* arg_ptn = ptnode_adr(arg->_idx); 958 assert(arg_ptn != NULL, "should be registered"); 959 PointsToNode::EscapeState arg_esc = arg_ptn->escape_state(); 960 if (is_arraycopy || arg_esc < PointsToNode::ArgEscape) { 961 assert(aat == Type::TOP || aat == TypePtr::NULL_PTR || 962 aat->isa_ptr() != NULL, "expecting an Ptr"); 963 bool arg_has_oops = aat->isa_oopptr() && 964 (aat->isa_oopptr()->klass() == NULL || aat->isa_instptr() || 965 (aat->isa_aryptr() && aat->isa_aryptr()->klass()->is_obj_array_klass())); 966 if (i == TypeFunc::Parms) { 967 src_has_oops = arg_has_oops; 968 } 969 // 970 // src or dst could be j.l.Object when other is basic type array: 971 // 972 // arraycopy(char[],0,Object*,0,size); 973 // arraycopy(Object*,0,char[],0,size); 974 // 975 // Don't add edges in such cases. 976 // 977 bool arg_is_arraycopy_dest = src_has_oops && is_arraycopy && 978 arg_has_oops && (i > TypeFunc::Parms); 979 #ifdef ASSERT 980 if (!(is_arraycopy || 981 (call->as_CallLeaf()->_name != NULL && 982 (strcmp(call->as_CallLeaf()->_name, "g1_wb_pre") == 0 || 983 strcmp(call->as_CallLeaf()->_name, "g1_wb_post") == 0 || 984 strcmp(call->as_CallLeaf()->_name, "updateBytesCRC32") == 0 || 985 strcmp(call->as_CallLeaf()->_name, "updateBytesCRC32C") == 0 || 986 strcmp(call->as_CallLeaf()->_name, "updateBytesAdler32") == 0 || 987 strcmp(call->as_CallLeaf()->_name, "aescrypt_encryptBlock") == 0 || 988 strcmp(call->as_CallLeaf()->_name, "aescrypt_decryptBlock") == 0 || 989 strcmp(call->as_CallLeaf()->_name, "cipherBlockChaining_encryptAESCrypt") == 0 || 990 strcmp(call->as_CallLeaf()->_name, "cipherBlockChaining_decryptAESCrypt") == 0 || 991 strcmp(call->as_CallLeaf()->_name, "counterMode_AESCrypt") == 0 || 992 strcmp(call->as_CallLeaf()->_name, "ghash_processBlocks") == 0 || 993 strcmp(call->as_CallLeaf()->_name, "implEncode") == 0 || 994 strcmp(call->as_CallLeaf()->_name, "sha1_implCompress") == 0 || 995 strcmp(call->as_CallLeaf()->_name, "sha1_implCompressMB") == 0 || 996 strcmp(call->as_CallLeaf()->_name, "sha256_implCompress") == 0 || 997 strcmp(call->as_CallLeaf()->_name, "sha256_implCompressMB") == 0 || 998 strcmp(call->as_CallLeaf()->_name, "sha512_implCompress") == 0 || 999 strcmp(call->as_CallLeaf()->_name, "sha512_implCompressMB") == 0 || 1000 strcmp(call->as_CallLeaf()->_name, "multiplyToLen") == 0 || 1001 strcmp(call->as_CallLeaf()->_name, "squareToLen") == 0 || 1002 strcmp(call->as_CallLeaf()->_name, "mulAdd") == 0 || 1003 strcmp(call->as_CallLeaf()->_name, "montgomery_multiply") == 0 || 1004 strcmp(call->as_CallLeaf()->_name, "montgomery_square") == 0 || 1005 strcmp(call->as_CallLeaf()->_name, "vectorizedMismatch") == 0) 1006 ))) { 1007 call->dump(); 1008 fatal("EA unexpected CallLeaf %s", call->as_CallLeaf()->_name); 1009 } 1010 #endif 1011 // Always process arraycopy's destination object since 1012 // we need to add all possible edges to references in 1013 // source object. 1014 if (arg_esc >= PointsToNode::ArgEscape && 1015 !arg_is_arraycopy_dest) { 1016 continue; 1017 } 1018 PointsToNode::EscapeState es = PointsToNode::ArgEscape; 1019 if (call->is_ArrayCopy()) { 1020 ArrayCopyNode* ac = call->as_ArrayCopy(); 1021 if (ac->is_clonebasic() || 1022 ac->is_arraycopy_validated() || 1023 ac->is_copyof_validated() || 1024 ac->is_copyofrange_validated()) { 1025 es = PointsToNode::NoEscape; 1026 } 1027 } 1028 set_escape_state(arg_ptn, es); 1029 if (arg_is_arraycopy_dest) { 1030 Node* src = call->in(TypeFunc::Parms); 1031 if (src->is_AddP()) { 1032 src = get_addp_base(src); 1033 } 1034 PointsToNode* src_ptn = ptnode_adr(src->_idx); 1035 assert(src_ptn != NULL, "should be registered"); 1036 if (arg_ptn != src_ptn) { 1037 // Special arraycopy edge: 1038 // A destination object's field can't have the source object 1039 // as base since objects escape states are not related. 1040 // Only escape state of destination object's fields affects 1041 // escape state of fields in source object. 1042 add_arraycopy(call, es, src_ptn, arg_ptn); 1043 } 1044 } 1045 } 1046 } 1047 break; 1048 } 1049 case Op_CallStaticJava: { 1050 // For a static call, we know exactly what method is being called. 1051 // Use bytecode estimator to record the call's escape affects 1052 #ifdef ASSERT 1053 const char* name = call->as_CallStaticJava()->_name; 1054 assert((name == NULL || strcmp(name, "uncommon_trap") != 0), "normal calls only"); 1055 #endif 1056 ciMethod* meth = call->as_CallJava()->method(); 1057 if ((meth != NULL) && meth->is_boxing_method()) { 1058 break; // Boxing methods do not modify any oops. 1059 } 1060 BCEscapeAnalyzer* call_analyzer = (meth !=NULL) ? meth->get_bcea() : NULL; 1061 // fall-through if not a Java method or no analyzer information 1062 if (call_analyzer != NULL) { 1063 PointsToNode* call_ptn = ptnode_adr(call->_idx); 1064 const TypeTuple* d = call->tf()->domain(); 1065 for (uint i = TypeFunc::Parms; i < d->cnt(); i++) { 1066 const Type* at = d->field_at(i); 1067 int k = i - TypeFunc::Parms; 1068 Node* arg = call->in(i); 1069 PointsToNode* arg_ptn = ptnode_adr(arg->_idx); 1070 if (at->isa_ptr() != NULL && 1071 call_analyzer->is_arg_returned(k)) { 1072 // The call returns arguments. 1073 if (call_ptn != NULL) { // Is call's result used? 1074 assert(call_ptn->is_LocalVar(), "node should be registered"); 1075 assert(arg_ptn != NULL, "node should be registered"); 1076 add_edge(call_ptn, arg_ptn); 1077 } 1078 } 1079 if (at->isa_oopptr() != NULL && 1080 arg_ptn->escape_state() < PointsToNode::GlobalEscape) { 1081 if (!call_analyzer->is_arg_stack(k)) { 1082 // The argument global escapes 1083 set_escape_state(arg_ptn, PointsToNode::GlobalEscape); 1084 } else { 1085 set_escape_state(arg_ptn, PointsToNode::ArgEscape); 1086 if (!call_analyzer->is_arg_local(k)) { 1087 // The argument itself doesn't escape, but any fields might 1088 set_fields_escape_state(arg_ptn, PointsToNode::GlobalEscape); 1089 } 1090 } 1091 } 1092 } 1093 if (call_ptn != NULL && call_ptn->is_LocalVar()) { 1094 // The call returns arguments. 1095 assert(call_ptn->edge_count() > 0, "sanity"); 1096 if (!call_analyzer->is_return_local()) { 1097 // Returns also unknown object. 1098 add_edge(call_ptn, phantom_obj); 1099 } 1100 } 1101 break; 1102 } 1103 } 1104 default: { 1105 // Fall-through here if not a Java method or no analyzer information 1106 // or some other type of call, assume the worst case: all arguments 1107 // globally escape. 1108 const TypeTuple* d = call->tf()->domain(); 1109 for (uint i = TypeFunc::Parms; i < d->cnt(); i++) { 1110 const Type* at = d->field_at(i); 1111 if (at->isa_oopptr() != NULL) { 1112 Node* arg = call->in(i); 1113 if (arg->is_AddP()) { 1114 arg = get_addp_base(arg); 1115 } 1116 assert(ptnode_adr(arg->_idx) != NULL, "should be defined already"); 1117 set_escape_state(ptnode_adr(arg->_idx), PointsToNode::GlobalEscape); 1118 } 1119 } 1120 } 1121 } 1122 } 1123 1124 1125 // Finish Graph construction. 1126 bool ConnectionGraph::complete_connection_graph( 1127 GrowableArray<PointsToNode*>& ptnodes_worklist, 1128 GrowableArray<JavaObjectNode*>& non_escaped_worklist, 1129 GrowableArray<JavaObjectNode*>& java_objects_worklist, 1130 GrowableArray<FieldNode*>& oop_fields_worklist) { 1131 // Normally only 1-3 passes needed to build Connection Graph depending 1132 // on graph complexity. Observed 8 passes in jvm2008 compiler.compiler. 1133 // Set limit to 20 to catch situation when something did go wrong and 1134 // bailout Escape Analysis. 1135 // Also limit build time to 20 sec (60 in debug VM), EscapeAnalysisTimeout flag. 1136 #define CG_BUILD_ITER_LIMIT 20 1137 1138 // Propagate GlobalEscape and ArgEscape escape states and check that 1139 // we still have non-escaping objects. The method pushs on _worklist 1140 // Field nodes which reference phantom_object. 1141 if (!find_non_escaped_objects(ptnodes_worklist, non_escaped_worklist)) { 1142 return false; // Nothing to do. 1143 } 1144 // Now propagate references to all JavaObject nodes. 1145 int java_objects_length = java_objects_worklist.length(); 1146 elapsedTimer time; 1147 bool timeout = false; 1148 int new_edges = 1; 1149 int iterations = 0; 1150 do { 1151 while ((new_edges > 0) && 1152 (iterations++ < CG_BUILD_ITER_LIMIT)) { 1153 double start_time = time.seconds(); 1154 time.start(); 1155 new_edges = 0; 1156 // Propagate references to phantom_object for nodes pushed on _worklist 1157 // by find_non_escaped_objects() and find_field_value(). 1158 new_edges += add_java_object_edges(phantom_obj, false); 1159 for (int next = 0; next < java_objects_length; ++next) { 1160 JavaObjectNode* ptn = java_objects_worklist.at(next); 1161 new_edges += add_java_object_edges(ptn, true); 1162 1163 #define SAMPLE_SIZE 4 1164 if ((next % SAMPLE_SIZE) == 0) { 1165 // Each 4 iterations calculate how much time it will take 1166 // to complete graph construction. 1167 time.stop(); 1168 // Poll for requests from shutdown mechanism to quiesce compiler 1169 // because Connection graph construction may take long time. 1170 CompileBroker::maybe_block(); 1171 double stop_time = time.seconds(); 1172 double time_per_iter = (stop_time - start_time) / (double)SAMPLE_SIZE; 1173 double time_until_end = time_per_iter * (double)(java_objects_length - next); 1174 if ((start_time + time_until_end) >= EscapeAnalysisTimeout) { 1175 timeout = true; 1176 break; // Timeout 1177 } 1178 start_time = stop_time; 1179 time.start(); 1180 } 1181 #undef SAMPLE_SIZE 1182 1183 } 1184 if (timeout) break; 1185 if (new_edges > 0) { 1186 // Update escape states on each iteration if graph was updated. 1187 if (!find_non_escaped_objects(ptnodes_worklist, non_escaped_worklist)) { 1188 return false; // Nothing to do. 1189 } 1190 } 1191 time.stop(); 1192 if (time.seconds() >= EscapeAnalysisTimeout) { 1193 timeout = true; 1194 break; 1195 } 1196 } 1197 if ((iterations < CG_BUILD_ITER_LIMIT) && !timeout) { 1198 time.start(); 1199 // Find fields which have unknown value. 1200 int fields_length = oop_fields_worklist.length(); 1201 for (int next = 0; next < fields_length; next++) { 1202 FieldNode* field = oop_fields_worklist.at(next); 1203 if (field->edge_count() == 0) { 1204 new_edges += find_field_value(field); 1205 // This code may added new edges to phantom_object. 1206 // Need an other cycle to propagate references to phantom_object. 1207 } 1208 } 1209 time.stop(); 1210 if (time.seconds() >= EscapeAnalysisTimeout) { 1211 timeout = true; 1212 break; 1213 } 1214 } else { 1215 new_edges = 0; // Bailout 1216 } 1217 } while (new_edges > 0); 1218 1219 // Bailout if passed limits. 1220 if ((iterations >= CG_BUILD_ITER_LIMIT) || timeout) { 1221 Compile* C = _compile; 1222 if (C->log() != NULL) { 1223 C->log()->begin_elem("connectionGraph_bailout reason='reached "); 1224 C->log()->text("%s", timeout ? "time" : "iterations"); 1225 C->log()->end_elem(" limit'"); 1226 } 1227 assert(ExitEscapeAnalysisOnTimeout, "infinite EA connection graph build (%f sec, %d iterations) with %d nodes and worklist size %d", 1228 time.seconds(), iterations, nodes_size(), ptnodes_worklist.length()); 1229 // Possible infinite build_connection_graph loop, 1230 // bailout (no changes to ideal graph were made). 1231 return false; 1232 } 1233 #ifdef ASSERT 1234 if (Verbose && PrintEscapeAnalysis) { 1235 tty->print_cr("EA: %d iterations to build connection graph with %d nodes and worklist size %d", 1236 iterations, nodes_size(), ptnodes_worklist.length()); 1237 } 1238 #endif 1239 1240 #undef CG_BUILD_ITER_LIMIT 1241 1242 // Find fields initialized by NULL for non-escaping Allocations. 1243 int non_escaped_length = non_escaped_worklist.length(); 1244 for (int next = 0; next < non_escaped_length; next++) { 1245 JavaObjectNode* ptn = non_escaped_worklist.at(next); 1246 PointsToNode::EscapeState es = ptn->escape_state(); 1247 assert(es <= PointsToNode::ArgEscape, "sanity"); 1248 if (es == PointsToNode::NoEscape) { 1249 if (find_init_values(ptn, null_obj, _igvn) > 0) { 1250 // Adding references to NULL object does not change escape states 1251 // since it does not escape. Also no fields are added to NULL object. 1252 add_java_object_edges(null_obj, false); 1253 } 1254 } 1255 Node* n = ptn->ideal_node(); 1256 if (n->is_Allocate()) { 1257 // The object allocated by this Allocate node will never be 1258 // seen by an other thread. Mark it so that when it is 1259 // expanded no MemBarStoreStore is added. 1260 InitializeNode* ini = n->as_Allocate()->initialization(); 1261 if (ini != NULL) 1262 ini->set_does_not_escape(); 1263 } 1264 } 1265 return true; // Finished graph construction. 1266 } 1267 1268 // Propagate GlobalEscape and ArgEscape escape states to all nodes 1269 // and check that we still have non-escaping java objects. 1270 bool ConnectionGraph::find_non_escaped_objects(GrowableArray<PointsToNode*>& ptnodes_worklist, 1271 GrowableArray<JavaObjectNode*>& non_escaped_worklist) { 1272 GrowableArray<PointsToNode*> escape_worklist; 1273 // First, put all nodes with GlobalEscape and ArgEscape states on worklist. 1274 int ptnodes_length = ptnodes_worklist.length(); 1275 for (int next = 0; next < ptnodes_length; ++next) { 1276 PointsToNode* ptn = ptnodes_worklist.at(next); 1277 if (ptn->escape_state() >= PointsToNode::ArgEscape || 1278 ptn->fields_escape_state() >= PointsToNode::ArgEscape) { 1279 escape_worklist.push(ptn); 1280 } 1281 } 1282 // Set escape states to referenced nodes (edges list). 1283 while (escape_worklist.length() > 0) { 1284 PointsToNode* ptn = escape_worklist.pop(); 1285 PointsToNode::EscapeState es = ptn->escape_state(); 1286 PointsToNode::EscapeState field_es = ptn->fields_escape_state(); 1287 if (ptn->is_Field() && ptn->as_Field()->is_oop() && 1288 es >= PointsToNode::ArgEscape) { 1289 // GlobalEscape or ArgEscape state of field means it has unknown value. 1290 if (add_edge(ptn, phantom_obj)) { 1291 // New edge was added 1292 add_field_uses_to_worklist(ptn->as_Field()); 1293 } 1294 } 1295 for (EdgeIterator i(ptn); i.has_next(); i.next()) { 1296 PointsToNode* e = i.get(); 1297 if (e->is_Arraycopy()) { 1298 assert(ptn->arraycopy_dst(), "sanity"); 1299 // Propagate only fields escape state through arraycopy edge. 1300 if (e->fields_escape_state() < field_es) { 1301 set_fields_escape_state(e, field_es); 1302 escape_worklist.push(e); 1303 } 1304 } else if (es >= field_es) { 1305 // fields_escape_state is also set to 'es' if it is less than 'es'. 1306 if (e->escape_state() < es) { 1307 set_escape_state(e, es); 1308 escape_worklist.push(e); 1309 } 1310 } else { 1311 // Propagate field escape state. 1312 bool es_changed = false; 1313 if (e->fields_escape_state() < field_es) { 1314 set_fields_escape_state(e, field_es); 1315 es_changed = true; 1316 } 1317 if ((e->escape_state() < field_es) && 1318 e->is_Field() && ptn->is_JavaObject() && 1319 e->as_Field()->is_oop()) { 1320 // Change escape state of referenced fields. 1321 set_escape_state(e, field_es); 1322 es_changed = true; 1323 } else if (e->escape_state() < es) { 1324 set_escape_state(e, es); 1325 es_changed = true; 1326 } 1327 if (es_changed) { 1328 escape_worklist.push(e); 1329 } 1330 } 1331 } 1332 } 1333 // Remove escaped objects from non_escaped list. 1334 for (int next = non_escaped_worklist.length()-1; next >= 0 ; --next) { 1335 JavaObjectNode* ptn = non_escaped_worklist.at(next); 1336 if (ptn->escape_state() >= PointsToNode::GlobalEscape) { 1337 non_escaped_worklist.delete_at(next); 1338 } 1339 if (ptn->escape_state() == PointsToNode::NoEscape) { 1340 // Find fields in non-escaped allocations which have unknown value. 1341 find_init_values(ptn, phantom_obj, NULL); 1342 } 1343 } 1344 return (non_escaped_worklist.length() > 0); 1345 } 1346 1347 // Add all references to JavaObject node by walking over all uses. 1348 int ConnectionGraph::add_java_object_edges(JavaObjectNode* jobj, bool populate_worklist) { 1349 int new_edges = 0; 1350 if (populate_worklist) { 1351 // Populate _worklist by uses of jobj's uses. 1352 for (UseIterator i(jobj); i.has_next(); i.next()) { 1353 PointsToNode* use = i.get(); 1354 if (use->is_Arraycopy()) 1355 continue; 1356 add_uses_to_worklist(use); 1357 if (use->is_Field() && use->as_Field()->is_oop()) { 1358 // Put on worklist all field's uses (loads) and 1359 // related field nodes (same base and offset). 1360 add_field_uses_to_worklist(use->as_Field()); 1361 } 1362 } 1363 } 1364 for (int l = 0; l < _worklist.length(); l++) { 1365 PointsToNode* use = _worklist.at(l); 1366 if (PointsToNode::is_base_use(use)) { 1367 // Add reference from jobj to field and from field to jobj (field's base). 1368 use = PointsToNode::get_use_node(use)->as_Field(); 1369 if (add_base(use->as_Field(), jobj)) { 1370 new_edges++; 1371 } 1372 continue; 1373 } 1374 assert(!use->is_JavaObject(), "sanity"); 1375 if (use->is_Arraycopy()) { 1376 if (jobj == null_obj) // NULL object does not have field edges 1377 continue; 1378 // Added edge from Arraycopy node to arraycopy's source java object 1379 if (add_edge(use, jobj)) { 1380 jobj->set_arraycopy_src(); 1381 new_edges++; 1382 } 1383 // and stop here. 1384 continue; 1385 } 1386 if (!add_edge(use, jobj)) 1387 continue; // No new edge added, there was such edge already. 1388 new_edges++; 1389 if (use->is_LocalVar()) { 1390 add_uses_to_worklist(use); 1391 if (use->arraycopy_dst()) { 1392 for (EdgeIterator i(use); i.has_next(); i.next()) { 1393 PointsToNode* e = i.get(); 1394 if (e->is_Arraycopy()) { 1395 if (jobj == null_obj) // NULL object does not have field edges 1396 continue; 1397 // Add edge from arraycopy's destination java object to Arraycopy node. 1398 if (add_edge(jobj, e)) { 1399 new_edges++; 1400 jobj->set_arraycopy_dst(); 1401 } 1402 } 1403 } 1404 } 1405 } else { 1406 // Added new edge to stored in field values. 1407 // Put on worklist all field's uses (loads) and 1408 // related field nodes (same base and offset). 1409 add_field_uses_to_worklist(use->as_Field()); 1410 } 1411 } 1412 _worklist.clear(); 1413 _in_worklist.Reset(); 1414 return new_edges; 1415 } 1416 1417 // Put on worklist all related field nodes. 1418 void ConnectionGraph::add_field_uses_to_worklist(FieldNode* field) { 1419 assert(field->is_oop(), "sanity"); 1420 int offset = field->offset(); 1421 add_uses_to_worklist(field); 1422 // Loop over all bases of this field and push on worklist Field nodes 1423 // with the same offset and base (since they may reference the same field). 1424 for (BaseIterator i(field); i.has_next(); i.next()) { 1425 PointsToNode* base = i.get(); 1426 add_fields_to_worklist(field, base); 1427 // Check if the base was source object of arraycopy and go over arraycopy's 1428 // destination objects since values stored to a field of source object are 1429 // accessable by uses (loads) of fields of destination objects. 1430 if (base->arraycopy_src()) { 1431 for (UseIterator j(base); j.has_next(); j.next()) { 1432 PointsToNode* arycp = j.get(); 1433 if (arycp->is_Arraycopy()) { 1434 for (UseIterator k(arycp); k.has_next(); k.next()) { 1435 PointsToNode* abase = k.get(); 1436 if (abase->arraycopy_dst() && abase != base) { 1437 // Look for the same arraycopy reference. 1438 add_fields_to_worklist(field, abase); 1439 } 1440 } 1441 } 1442 } 1443 } 1444 } 1445 } 1446 1447 // Put on worklist all related field nodes. 1448 void ConnectionGraph::add_fields_to_worklist(FieldNode* field, PointsToNode* base) { 1449 int offset = field->offset(); 1450 if (base->is_LocalVar()) { 1451 for (UseIterator j(base); j.has_next(); j.next()) { 1452 PointsToNode* f = j.get(); 1453 if (PointsToNode::is_base_use(f)) { // Field 1454 f = PointsToNode::get_use_node(f); 1455 if (f == field || !f->as_Field()->is_oop()) 1456 continue; 1457 int offs = f->as_Field()->offset(); 1458 if (offs == offset || offset == Type::OffsetBot || offs == Type::OffsetBot) { 1459 add_to_worklist(f); 1460 } 1461 } 1462 } 1463 } else { 1464 assert(base->is_JavaObject(), "sanity"); 1465 if (// Skip phantom_object since it is only used to indicate that 1466 // this field's content globally escapes. 1467 (base != phantom_obj) && 1468 // NULL object node does not have fields. 1469 (base != null_obj)) { 1470 for (EdgeIterator i(base); i.has_next(); i.next()) { 1471 PointsToNode* f = i.get(); 1472 // Skip arraycopy edge since store to destination object field 1473 // does not update value in source object field. 1474 if (f->is_Arraycopy()) { 1475 assert(base->arraycopy_dst(), "sanity"); 1476 continue; 1477 } 1478 if (f == field || !f->as_Field()->is_oop()) 1479 continue; 1480 int offs = f->as_Field()->offset(); 1481 if (offs == offset || offset == Type::OffsetBot || offs == Type::OffsetBot) { 1482 add_to_worklist(f); 1483 } 1484 } 1485 } 1486 } 1487 } 1488 1489 // Find fields which have unknown value. 1490 int ConnectionGraph::find_field_value(FieldNode* field) { 1491 // Escaped fields should have init value already. 1492 assert(field->escape_state() == PointsToNode::NoEscape, "sanity"); 1493 int new_edges = 0; 1494 for (BaseIterator i(field); i.has_next(); i.next()) { 1495 PointsToNode* base = i.get(); 1496 if (base->is_JavaObject()) { 1497 // Skip Allocate's fields which will be processed later. 1498 if (base->ideal_node()->is_Allocate()) 1499 return 0; 1500 assert(base == null_obj, "only NULL ptr base expected here"); 1501 } 1502 } 1503 if (add_edge(field, phantom_obj)) { 1504 // New edge was added 1505 new_edges++; 1506 add_field_uses_to_worklist(field); 1507 } 1508 return new_edges; 1509 } 1510 1511 // Find fields initializing values for allocations. 1512 int ConnectionGraph::find_init_values(JavaObjectNode* pta, PointsToNode* init_val, PhaseTransform* phase) { 1513 assert(pta->escape_state() == PointsToNode::NoEscape, "Not escaped Allocate nodes only"); 1514 int new_edges = 0; 1515 Node* alloc = pta->ideal_node(); 1516 if (init_val == phantom_obj) { 1517 // Do nothing for Allocate nodes since its fields values are 1518 // "known" unless they are initialized by arraycopy/clone. 1519 if (alloc->is_Allocate() && !pta->arraycopy_dst()) 1520 return 0; 1521 assert(pta->arraycopy_dst() || alloc->as_CallStaticJava(), "sanity"); 1522 #ifdef ASSERT 1523 if (!pta->arraycopy_dst() && alloc->as_CallStaticJava()->method() == NULL) { 1524 const char* name = alloc->as_CallStaticJava()->_name; 1525 assert(strncmp(name, "_multianewarray", 15) == 0, "sanity"); 1526 } 1527 #endif 1528 // Non-escaped allocation returned from Java or runtime call have 1529 // unknown values in fields. 1530 for (EdgeIterator i(pta); i.has_next(); i.next()) { 1531 PointsToNode* field = i.get(); 1532 if (field->is_Field() && field->as_Field()->is_oop()) { 1533 if (add_edge(field, phantom_obj)) { 1534 // New edge was added 1535 new_edges++; 1536 add_field_uses_to_worklist(field->as_Field()); 1537 } 1538 } 1539 } 1540 return new_edges; 1541 } 1542 assert(init_val == null_obj, "sanity"); 1543 // Do nothing for Call nodes since its fields values are unknown. 1544 if (!alloc->is_Allocate()) 1545 return 0; 1546 1547 InitializeNode* ini = alloc->as_Allocate()->initialization(); 1548 bool visited_bottom_offset = false; 1549 GrowableArray<int> offsets_worklist; 1550 1551 // Check if an oop field's initializing value is recorded and add 1552 // a corresponding NULL if field's value if it is not recorded. 1553 // Connection Graph does not record a default initialization by NULL 1554 // captured by Initialize node. 1555 // 1556 for (EdgeIterator i(pta); i.has_next(); i.next()) { 1557 PointsToNode* field = i.get(); // Field (AddP) 1558 if (!field->is_Field() || !field->as_Field()->is_oop()) 1559 continue; // Not oop field 1560 int offset = field->as_Field()->offset(); 1561 if (offset == Type::OffsetBot) { 1562 if (!visited_bottom_offset) { 1563 // OffsetBot is used to reference array's element, 1564 // always add reference to NULL to all Field nodes since we don't 1565 // known which element is referenced. 1566 if (add_edge(field, null_obj)) { 1567 // New edge was added 1568 new_edges++; 1569 add_field_uses_to_worklist(field->as_Field()); 1570 visited_bottom_offset = true; 1571 } 1572 } 1573 } else { 1574 // Check only oop fields. 1575 const Type* adr_type = field->ideal_node()->as_AddP()->bottom_type(); 1576 if (adr_type->isa_rawptr()) { 1577 #ifdef ASSERT 1578 // Raw pointers are used for initializing stores so skip it 1579 // since it should be recorded already 1580 Node* base = get_addp_base(field->ideal_node()); 1581 assert(adr_type->isa_rawptr() && base->is_Proj() && 1582 (base->in(0) == alloc),"unexpected pointer type"); 1583 #endif 1584 continue; 1585 } 1586 if (!offsets_worklist.contains(offset)) { 1587 offsets_worklist.append(offset); 1588 Node* value = NULL; 1589 if (ini != NULL) { 1590 // StoreP::memory_type() == T_ADDRESS 1591 BasicType ft = UseCompressedOops ? T_NARROWOOP : T_ADDRESS; 1592 Node* store = ini->find_captured_store(offset, type2aelembytes(ft, true), phase); 1593 // Make sure initializing store has the same type as this AddP. 1594 // This AddP may reference non existing field because it is on a 1595 // dead branch of bimorphic call which is not eliminated yet. 1596 if (store != NULL && store->is_Store() && 1597 store->as_Store()->memory_type() == ft) { 1598 value = store->in(MemNode::ValueIn); 1599 #ifdef ASSERT 1600 if (VerifyConnectionGraph) { 1601 // Verify that AddP already points to all objects the value points to. 1602 PointsToNode* val = ptnode_adr(value->_idx); 1603 assert((val != NULL), "should be processed already"); 1604 PointsToNode* missed_obj = NULL; 1605 if (val->is_JavaObject()) { 1606 if (!field->points_to(val->as_JavaObject())) { 1607 missed_obj = val; 1608 } 1609 } else { 1610 if (!val->is_LocalVar() || (val->edge_count() == 0)) { 1611 tty->print_cr("----------init store has invalid value -----"); 1612 store->dump(); 1613 val->dump(); 1614 assert(val->is_LocalVar() && (val->edge_count() > 0), "should be processed already"); 1615 } 1616 for (EdgeIterator j(val); j.has_next(); j.next()) { 1617 PointsToNode* obj = j.get(); 1618 if (obj->is_JavaObject()) { 1619 if (!field->points_to(obj->as_JavaObject())) { 1620 missed_obj = obj; 1621 break; 1622 } 1623 } 1624 } 1625 } 1626 if (missed_obj != NULL) { 1627 tty->print_cr("----------field---------------------------------"); 1628 field->dump(); 1629 tty->print_cr("----------missed referernce to object-----------"); 1630 missed_obj->dump(); 1631 tty->print_cr("----------object referernced by init store -----"); 1632 store->dump(); 1633 val->dump(); 1634 assert(!field->points_to(missed_obj->as_JavaObject()), "missed JavaObject reference"); 1635 } 1636 } 1637 #endif 1638 } else { 1639 // There could be initializing stores which follow allocation. 1640 // For example, a volatile field store is not collected 1641 // by Initialize node. 1642 // 1643 // Need to check for dependent loads to separate such stores from 1644 // stores which follow loads. For now, add initial value NULL so 1645 // that compare pointers optimization works correctly. 1646 } 1647 } 1648 if (value == NULL) { 1649 // A field's initializing value was not recorded. Add NULL. 1650 if (add_edge(field, null_obj)) { 1651 // New edge was added 1652 new_edges++; 1653 add_field_uses_to_worklist(field->as_Field()); 1654 } 1655 } 1656 } 1657 } 1658 } 1659 return new_edges; 1660 } 1661 1662 // Adjust scalar_replaceable state after Connection Graph is built. 1663 void ConnectionGraph::adjust_scalar_replaceable_state(JavaObjectNode* jobj) { 1664 // Search for non-escaping objects which are not scalar replaceable 1665 // and mark them to propagate the state to referenced objects. 1666 1667 // 1. An object is not scalar replaceable if the field into which it is 1668 // stored has unknown offset (stored into unknown element of an array). 1669 // 1670 for (UseIterator i(jobj); i.has_next(); i.next()) { 1671 PointsToNode* use = i.get(); 1672 if (use->is_Arraycopy()) { 1673 continue; 1674 } 1675 if (use->is_Field()) { 1676 FieldNode* field = use->as_Field(); 1677 assert(field->is_oop() && field->scalar_replaceable(), "sanity"); 1678 if (field->offset() == Type::OffsetBot) { 1679 jobj->set_scalar_replaceable(false); 1680 return; 1681 } 1682 // 2. An object is not scalar replaceable if the field into which it is 1683 // stored has multiple bases one of which is null. 1684 if (field->base_count() > 1) { 1685 for (BaseIterator i(field); i.has_next(); i.next()) { 1686 PointsToNode* base = i.get(); 1687 if (base == null_obj) { 1688 jobj->set_scalar_replaceable(false); 1689 return; 1690 } 1691 } 1692 } 1693 } 1694 assert(use->is_Field() || use->is_LocalVar(), "sanity"); 1695 // 3. An object is not scalar replaceable if it is merged with other objects. 1696 for (EdgeIterator j(use); j.has_next(); j.next()) { 1697 PointsToNode* ptn = j.get(); 1698 if (ptn->is_JavaObject() && ptn != jobj) { 1699 // Mark all objects. 1700 jobj->set_scalar_replaceable(false); 1701 ptn->set_scalar_replaceable(false); 1702 } 1703 } 1704 if (!jobj->scalar_replaceable()) { 1705 return; 1706 } 1707 } 1708 1709 for (EdgeIterator j(jobj); j.has_next(); j.next()) { 1710 if (j.get()->is_Arraycopy()) { 1711 continue; 1712 } 1713 1714 // Non-escaping object node should point only to field nodes. 1715 FieldNode* field = j.get()->as_Field(); 1716 int offset = field->as_Field()->offset(); 1717 1718 // 4. An object is not scalar replaceable if it has a field with unknown 1719 // offset (array's element is accessed in loop). 1720 if (offset == Type::OffsetBot) { 1721 jobj->set_scalar_replaceable(false); 1722 return; 1723 } 1724 // 5. Currently an object is not scalar replaceable if a LoadStore node 1725 // access its field since the field value is unknown after it. 1726 // 1727 Node* n = field->ideal_node(); 1728 for (DUIterator_Fast imax, i = n->fast_outs(imax); i < imax; i++) { 1729 if (n->fast_out(i)->is_LoadStore()) { 1730 jobj->set_scalar_replaceable(false); 1731 return; 1732 } 1733 } 1734 1735 // 6. Or the address may point to more then one object. This may produce 1736 // the false positive result (set not scalar replaceable) 1737 // since the flow-insensitive escape analysis can't separate 1738 // the case when stores overwrite the field's value from the case 1739 // when stores happened on different control branches. 1740 // 1741 // Note: it will disable scalar replacement in some cases: 1742 // 1743 // Point p[] = new Point[1]; 1744 // p[0] = new Point(); // Will be not scalar replaced 1745 // 1746 // but it will save us from incorrect optimizations in next cases: 1747 // 1748 // Point p[] = new Point[1]; 1749 // if ( x ) p[0] = new Point(); // Will be not scalar replaced 1750 // 1751 if (field->base_count() > 1) { 1752 for (BaseIterator i(field); i.has_next(); i.next()) { 1753 PointsToNode* base = i.get(); 1754 // Don't take into account LocalVar nodes which 1755 // may point to only one object which should be also 1756 // this field's base by now. 1757 if (base->is_JavaObject() && base != jobj) { 1758 // Mark all bases. 1759 jobj->set_scalar_replaceable(false); 1760 base->set_scalar_replaceable(false); 1761 } 1762 } 1763 } 1764 } 1765 } 1766 1767 #ifdef ASSERT 1768 void ConnectionGraph::verify_connection_graph( 1769 GrowableArray<PointsToNode*>& ptnodes_worklist, 1770 GrowableArray<JavaObjectNode*>& non_escaped_worklist, 1771 GrowableArray<JavaObjectNode*>& java_objects_worklist, 1772 GrowableArray<Node*>& addp_worklist) { 1773 // Verify that graph is complete - no new edges could be added. 1774 int java_objects_length = java_objects_worklist.length(); 1775 int non_escaped_length = non_escaped_worklist.length(); 1776 int new_edges = 0; 1777 for (int next = 0; next < java_objects_length; ++next) { 1778 JavaObjectNode* ptn = java_objects_worklist.at(next); 1779 new_edges += add_java_object_edges(ptn, true); 1780 } 1781 assert(new_edges == 0, "graph was not complete"); 1782 // Verify that escape state is final. 1783 int length = non_escaped_worklist.length(); 1784 find_non_escaped_objects(ptnodes_worklist, non_escaped_worklist); 1785 assert((non_escaped_length == non_escaped_worklist.length()) && 1786 (non_escaped_length == length) && 1787 (_worklist.length() == 0), "escape state was not final"); 1788 1789 // Verify fields information. 1790 int addp_length = addp_worklist.length(); 1791 for (int next = 0; next < addp_length; ++next ) { 1792 Node* n = addp_worklist.at(next); 1793 FieldNode* field = ptnode_adr(n->_idx)->as_Field(); 1794 if (field->is_oop()) { 1795 // Verify that field has all bases 1796 Node* base = get_addp_base(n); 1797 PointsToNode* ptn = ptnode_adr(base->_idx); 1798 if (ptn->is_JavaObject()) { 1799 assert(field->has_base(ptn->as_JavaObject()), "sanity"); 1800 } else { 1801 assert(ptn->is_LocalVar(), "sanity"); 1802 for (EdgeIterator i(ptn); i.has_next(); i.next()) { 1803 PointsToNode* e = i.get(); 1804 if (e->is_JavaObject()) { 1805 assert(field->has_base(e->as_JavaObject()), "sanity"); 1806 } 1807 } 1808 } 1809 // Verify that all fields have initializing values. 1810 if (field->edge_count() == 0) { 1811 tty->print_cr("----------field does not have references----------"); 1812 field->dump(); 1813 for (BaseIterator i(field); i.has_next(); i.next()) { 1814 PointsToNode* base = i.get(); 1815 tty->print_cr("----------field has next base---------------------"); 1816 base->dump(); 1817 if (base->is_JavaObject() && (base != phantom_obj) && (base != null_obj)) { 1818 tty->print_cr("----------base has fields-------------------------"); 1819 for (EdgeIterator j(base); j.has_next(); j.next()) { 1820 j.get()->dump(); 1821 } 1822 tty->print_cr("----------base has references---------------------"); 1823 for (UseIterator j(base); j.has_next(); j.next()) { 1824 j.get()->dump(); 1825 } 1826 } 1827 } 1828 for (UseIterator i(field); i.has_next(); i.next()) { 1829 i.get()->dump(); 1830 } 1831 assert(field->edge_count() > 0, "sanity"); 1832 } 1833 } 1834 } 1835 } 1836 #endif 1837 1838 // Optimize ideal graph. 1839 void ConnectionGraph::optimize_ideal_graph(GrowableArray<Node*>& ptr_cmp_worklist, 1840 GrowableArray<Node*>& storestore_worklist) { 1841 Compile* C = _compile; 1842 PhaseIterGVN* igvn = _igvn; 1843 if (EliminateLocks) { 1844 // Mark locks before changing ideal graph. 1845 int cnt = C->macro_count(); 1846 for( int i=0; i < cnt; i++ ) { 1847 Node *n = C->macro_node(i); 1848 if (n->is_AbstractLock()) { // Lock and Unlock nodes 1849 AbstractLockNode* alock = n->as_AbstractLock(); 1850 if (!alock->is_non_esc_obj()) { 1851 if (not_global_escape(alock->obj_node())) { 1852 assert(!alock->is_eliminated() || alock->is_coarsened(), "sanity"); 1853 // The lock could be marked eliminated by lock coarsening 1854 // code during first IGVN before EA. Replace coarsened flag 1855 // to eliminate all associated locks/unlocks. 1856 #ifdef ASSERT 1857 alock->log_lock_optimization(C, "eliminate_lock_set_non_esc3"); 1858 #endif 1859 alock->set_non_esc_obj(); 1860 } 1861 } 1862 } 1863 } 1864 } 1865 1866 if (OptimizePtrCompare) { 1867 // Add ConI(#CC_GT) and ConI(#CC_EQ). 1868 _pcmp_neq = igvn->makecon(TypeInt::CC_GT); 1869 _pcmp_eq = igvn->makecon(TypeInt::CC_EQ); 1870 // Optimize objects compare. 1871 while (ptr_cmp_worklist.length() != 0) { 1872 Node *n = ptr_cmp_worklist.pop(); 1873 Node *res = optimize_ptr_compare(n); 1874 if (res != NULL) { 1875 #ifndef PRODUCT 1876 if (PrintOptimizePtrCompare) { 1877 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")); 1878 if (Verbose) { 1879 n->dump(1); 1880 } 1881 } 1882 #endif 1883 igvn->replace_node(n, res); 1884 } 1885 } 1886 // cleanup 1887 if (_pcmp_neq->outcnt() == 0) 1888 igvn->hash_delete(_pcmp_neq); 1889 if (_pcmp_eq->outcnt() == 0) 1890 igvn->hash_delete(_pcmp_eq); 1891 } 1892 1893 // For MemBarStoreStore nodes added in library_call.cpp, check 1894 // escape status of associated AllocateNode and optimize out 1895 // MemBarStoreStore node if the allocated object never escapes. 1896 while (storestore_worklist.length() != 0) { 1897 Node *n = storestore_worklist.pop(); 1898 MemBarStoreStoreNode *storestore = n ->as_MemBarStoreStore(); 1899 Node *alloc = storestore->in(MemBarNode::Precedent)->in(0); 1900 assert (alloc->is_Allocate(), "storestore should point to AllocateNode"); 1901 if (not_global_escape(alloc)) { 1902 MemBarNode* mb = MemBarNode::make(C, Op_MemBarCPUOrder, Compile::AliasIdxBot); 1903 mb->init_req(TypeFunc::Memory, storestore->in(TypeFunc::Memory)); 1904 mb->init_req(TypeFunc::Control, storestore->in(TypeFunc::Control)); 1905 igvn->register_new_node_with_optimizer(mb); 1906 igvn->replace_node(storestore, mb); 1907 } 1908 } 1909 } 1910 1911 // Optimize objects compare. 1912 Node* ConnectionGraph::optimize_ptr_compare(Node* n) { 1913 assert(OptimizePtrCompare, "sanity"); 1914 PointsToNode* ptn1 = ptnode_adr(n->in(1)->_idx); 1915 PointsToNode* ptn2 = ptnode_adr(n->in(2)->_idx); 1916 JavaObjectNode* jobj1 = unique_java_object(n->in(1)); 1917 JavaObjectNode* jobj2 = unique_java_object(n->in(2)); 1918 assert(ptn1->is_JavaObject() || ptn1->is_LocalVar(), "sanity"); 1919 assert(ptn2->is_JavaObject() || ptn2->is_LocalVar(), "sanity"); 1920 1921 // Check simple cases first. 1922 if (jobj1 != NULL) { 1923 if (jobj1->escape_state() == PointsToNode::NoEscape) { 1924 if (jobj1 == jobj2) { 1925 // Comparing the same not escaping object. 1926 return _pcmp_eq; 1927 } 1928 Node* obj = jobj1->ideal_node(); 1929 // Comparing not escaping allocation. 1930 if ((obj->is_Allocate() || obj->is_CallStaticJava()) && 1931 !ptn2->points_to(jobj1)) { 1932 return _pcmp_neq; // This includes nullness check. 1933 } 1934 } 1935 } 1936 if (jobj2 != NULL) { 1937 if (jobj2->escape_state() == PointsToNode::NoEscape) { 1938 Node* obj = jobj2->ideal_node(); 1939 // Comparing not escaping allocation. 1940 if ((obj->is_Allocate() || obj->is_CallStaticJava()) && 1941 !ptn1->points_to(jobj2)) { 1942 return _pcmp_neq; // This includes nullness check. 1943 } 1944 } 1945 } 1946 if (jobj1 != NULL && jobj1 != phantom_obj && 1947 jobj2 != NULL && jobj2 != phantom_obj && 1948 jobj1->ideal_node()->is_Con() && 1949 jobj2->ideal_node()->is_Con()) { 1950 // Klass or String constants compare. Need to be careful with 1951 // compressed pointers - compare types of ConN and ConP instead of nodes. 1952 const Type* t1 = jobj1->ideal_node()->get_ptr_type(); 1953 const Type* t2 = jobj2->ideal_node()->get_ptr_type(); 1954 if (t1->make_ptr() == t2->make_ptr()) { 1955 return _pcmp_eq; 1956 } else { 1957 return _pcmp_neq; 1958 } 1959 } 1960 if (ptn1->meet(ptn2)) { 1961 return NULL; // Sets are not disjoint 1962 } 1963 1964 // Sets are disjoint. 1965 bool set1_has_unknown_ptr = ptn1->points_to(phantom_obj); 1966 bool set2_has_unknown_ptr = ptn2->points_to(phantom_obj); 1967 bool set1_has_null_ptr = ptn1->points_to(null_obj); 1968 bool set2_has_null_ptr = ptn2->points_to(null_obj); 1969 if ((set1_has_unknown_ptr && set2_has_null_ptr) || 1970 (set2_has_unknown_ptr && set1_has_null_ptr)) { 1971 // Check nullness of unknown object. 1972 return NULL; 1973 } 1974 1975 // Disjointness by itself is not sufficient since 1976 // alias analysis is not complete for escaped objects. 1977 // Disjoint sets are definitely unrelated only when 1978 // at least one set has only not escaping allocations. 1979 if (!set1_has_unknown_ptr && !set1_has_null_ptr) { 1980 if (ptn1->non_escaping_allocation()) { 1981 return _pcmp_neq; 1982 } 1983 } 1984 if (!set2_has_unknown_ptr && !set2_has_null_ptr) { 1985 if (ptn2->non_escaping_allocation()) { 1986 return _pcmp_neq; 1987 } 1988 } 1989 return NULL; 1990 } 1991 1992 // Connection Graph constuction functions. 1993 1994 void ConnectionGraph::add_local_var(Node *n, PointsToNode::EscapeState es) { 1995 PointsToNode* ptadr = _nodes.at(n->_idx); 1996 if (ptadr != NULL) { 1997 assert(ptadr->is_LocalVar() && ptadr->ideal_node() == n, "sanity"); 1998 return; 1999 } 2000 Compile* C = _compile; 2001 ptadr = new (C->comp_arena()) LocalVarNode(this, n, es); 2002 _nodes.at_put(n->_idx, ptadr); 2003 } 2004 2005 void ConnectionGraph::add_java_object(Node *n, PointsToNode::EscapeState es) { 2006 PointsToNode* ptadr = _nodes.at(n->_idx); 2007 if (ptadr != NULL) { 2008 assert(ptadr->is_JavaObject() && ptadr->ideal_node() == n, "sanity"); 2009 return; 2010 } 2011 Compile* C = _compile; 2012 ptadr = new (C->comp_arena()) JavaObjectNode(this, n, es); 2013 _nodes.at_put(n->_idx, ptadr); 2014 } 2015 2016 void ConnectionGraph::add_field(Node *n, PointsToNode::EscapeState es, int offset) { 2017 PointsToNode* ptadr = _nodes.at(n->_idx); 2018 if (ptadr != NULL) { 2019 assert(ptadr->is_Field() && ptadr->ideal_node() == n, "sanity"); 2020 return; 2021 } 2022 bool unsafe = false; 2023 bool is_oop = is_oop_field(n, offset, &unsafe); 2024 if (unsafe) { 2025 es = PointsToNode::GlobalEscape; 2026 } 2027 Compile* C = _compile; 2028 FieldNode* field = new (C->comp_arena()) FieldNode(this, n, es, offset, is_oop); 2029 _nodes.at_put(n->_idx, field); 2030 } 2031 2032 void ConnectionGraph::add_arraycopy(Node *n, PointsToNode::EscapeState es, 2033 PointsToNode* src, PointsToNode* dst) { 2034 assert(!src->is_Field() && !dst->is_Field(), "only for JavaObject and LocalVar"); 2035 assert((src != null_obj) && (dst != null_obj), "not for ConP NULL"); 2036 PointsToNode* ptadr = _nodes.at(n->_idx); 2037 if (ptadr != NULL) { 2038 assert(ptadr->is_Arraycopy() && ptadr->ideal_node() == n, "sanity"); 2039 return; 2040 } 2041 Compile* C = _compile; 2042 ptadr = new (C->comp_arena()) ArraycopyNode(this, n, es); 2043 _nodes.at_put(n->_idx, ptadr); 2044 // Add edge from arraycopy node to source object. 2045 (void)add_edge(ptadr, src); 2046 src->set_arraycopy_src(); 2047 // Add edge from destination object to arraycopy node. 2048 (void)add_edge(dst, ptadr); 2049 dst->set_arraycopy_dst(); 2050 } 2051 2052 bool ConnectionGraph::is_oop_field(Node* n, int offset, bool* unsafe) { 2053 const Type* adr_type = n->as_AddP()->bottom_type(); 2054 BasicType bt = T_INT; 2055 if (offset == Type::OffsetBot) { 2056 // Check only oop fields. 2057 if (!adr_type->isa_aryptr() || 2058 (adr_type->isa_aryptr()->klass() == NULL) || 2059 adr_type->isa_aryptr()->klass()->is_obj_array_klass()) { 2060 // OffsetBot is used to reference array's element. Ignore first AddP. 2061 if (find_second_addp(n, n->in(AddPNode::Base)) == NULL) { 2062 bt = T_OBJECT; 2063 } 2064 } 2065 } else if (offset != oopDesc::klass_offset_in_bytes()) { 2066 if (adr_type->isa_instptr()) { 2067 ciField* field = _compile->alias_type(adr_type->isa_instptr())->field(); 2068 if (field != NULL) { 2069 bt = field->layout_type(); 2070 } else { 2071 // Check for unsafe oop field access 2072 if (n->has_out_with(Op_StoreP, Op_LoadP, Op_StoreN, Op_LoadN) || 2073 n->has_out_with(Op_GetAndSetP, Op_GetAndSetN, Op_CompareAndExchangeP, Op_CompareAndExchangeN) || 2074 n->has_out_with(Op_CompareAndSwapP, Op_CompareAndSwapN, Op_WeakCompareAndSwapP, Op_WeakCompareAndSwapN)) { 2075 bt = T_OBJECT; 2076 (*unsafe) = true; 2077 } 2078 } 2079 } else if (adr_type->isa_aryptr()) { 2080 if (offset == arrayOopDesc::length_offset_in_bytes()) { 2081 // Ignore array length load. 2082 } else if (find_second_addp(n, n->in(AddPNode::Base)) != NULL) { 2083 // Ignore first AddP. 2084 } else { 2085 const Type* elemtype = adr_type->isa_aryptr()->elem(); 2086 bt = elemtype->array_element_basic_type(); 2087 } 2088 } else if (adr_type->isa_rawptr() || adr_type->isa_klassptr()) { 2089 // Allocation initialization, ThreadLocal field access, unsafe access 2090 if (n->has_out_with(Op_StoreP, Op_LoadP, Op_StoreN, Op_LoadN) || 2091 n->has_out_with(Op_GetAndSetP, Op_GetAndSetN, Op_CompareAndExchangeP, Op_CompareAndExchangeN) || 2092 n->has_out_with(Op_CompareAndSwapP, Op_CompareAndSwapN, Op_WeakCompareAndSwapP, Op_WeakCompareAndSwapN)) { 2093 bt = T_OBJECT; 2094 } 2095 } 2096 } 2097 return (bt == T_OBJECT || bt == T_NARROWOOP || bt == T_ARRAY); 2098 } 2099 2100 // Returns unique pointed java object or NULL. 2101 JavaObjectNode* ConnectionGraph::unique_java_object(Node *n) { 2102 assert(!_collecting, "should not call when contructed graph"); 2103 // If the node was created after the escape computation we can't answer. 2104 uint idx = n->_idx; 2105 if (idx >= nodes_size()) { 2106 return NULL; 2107 } 2108 PointsToNode* ptn = ptnode_adr(idx); 2109 if (ptn->is_JavaObject()) { 2110 return ptn->as_JavaObject(); 2111 } 2112 assert(ptn->is_LocalVar(), "sanity"); 2113 // Check all java objects it points to. 2114 JavaObjectNode* jobj = NULL; 2115 for (EdgeIterator i(ptn); i.has_next(); i.next()) { 2116 PointsToNode* e = i.get(); 2117 if (e->is_JavaObject()) { 2118 if (jobj == NULL) { 2119 jobj = e->as_JavaObject(); 2120 } else if (jobj != e) { 2121 return NULL; 2122 } 2123 } 2124 } 2125 return jobj; 2126 } 2127 2128 // Return true if this node points only to non-escaping allocations. 2129 bool PointsToNode::non_escaping_allocation() { 2130 if (is_JavaObject()) { 2131 Node* n = ideal_node(); 2132 if (n->is_Allocate() || n->is_CallStaticJava()) { 2133 return (escape_state() == PointsToNode::NoEscape); 2134 } else { 2135 return false; 2136 } 2137 } 2138 assert(is_LocalVar(), "sanity"); 2139 // Check all java objects it points to. 2140 for (EdgeIterator i(this); i.has_next(); i.next()) { 2141 PointsToNode* e = i.get(); 2142 if (e->is_JavaObject()) { 2143 Node* n = e->ideal_node(); 2144 if ((e->escape_state() != PointsToNode::NoEscape) || 2145 !(n->is_Allocate() || n->is_CallStaticJava())) { 2146 return false; 2147 } 2148 } 2149 } 2150 return true; 2151 } 2152 2153 // Return true if we know the node does not escape globally. 2154 bool ConnectionGraph::not_global_escape(Node *n) { 2155 assert(!_collecting, "should not call during graph construction"); 2156 // If the node was created after the escape computation we can't answer. 2157 uint idx = n->_idx; 2158 if (idx >= nodes_size()) { 2159 return false; 2160 } 2161 PointsToNode* ptn = ptnode_adr(idx); 2162 PointsToNode::EscapeState es = ptn->escape_state(); 2163 // If we have already computed a value, return it. 2164 if (es >= PointsToNode::GlobalEscape) 2165 return false; 2166 if (ptn->is_JavaObject()) { 2167 return true; // (es < PointsToNode::GlobalEscape); 2168 } 2169 assert(ptn->is_LocalVar(), "sanity"); 2170 // Check all java objects it points to. 2171 for (EdgeIterator i(ptn); i.has_next(); i.next()) { 2172 if (i.get()->escape_state() >= PointsToNode::GlobalEscape) 2173 return false; 2174 } 2175 return true; 2176 } 2177 2178 2179 // Helper functions 2180 2181 // Return true if this node points to specified node or nodes it points to. 2182 bool PointsToNode::points_to(JavaObjectNode* ptn) const { 2183 if (is_JavaObject()) { 2184 return (this == ptn); 2185 } 2186 assert(is_LocalVar() || is_Field(), "sanity"); 2187 for (EdgeIterator i(this); i.has_next(); i.next()) { 2188 if (i.get() == ptn) 2189 return true; 2190 } 2191 return false; 2192 } 2193 2194 // Return true if one node points to an other. 2195 bool PointsToNode::meet(PointsToNode* ptn) { 2196 if (this == ptn) { 2197 return true; 2198 } else if (ptn->is_JavaObject()) { 2199 return this->points_to(ptn->as_JavaObject()); 2200 } else if (this->is_JavaObject()) { 2201 return ptn->points_to(this->as_JavaObject()); 2202 } 2203 assert(this->is_LocalVar() && ptn->is_LocalVar(), "sanity"); 2204 int ptn_count = ptn->edge_count(); 2205 for (EdgeIterator i(this); i.has_next(); i.next()) { 2206 PointsToNode* this_e = i.get(); 2207 for (int j = 0; j < ptn_count; j++) { 2208 if (this_e == ptn->edge(j)) 2209 return true; 2210 } 2211 } 2212 return false; 2213 } 2214 2215 #ifdef ASSERT 2216 // Return true if bases point to this java object. 2217 bool FieldNode::has_base(JavaObjectNode* jobj) const { 2218 for (BaseIterator i(this); i.has_next(); i.next()) { 2219 if (i.get() == jobj) 2220 return true; 2221 } 2222 return false; 2223 } 2224 #endif 2225 2226 int ConnectionGraph::address_offset(Node* adr, PhaseTransform *phase) { 2227 const Type *adr_type = phase->type(adr); 2228 if (adr->is_AddP() && adr_type->isa_oopptr() == NULL && 2229 adr->in(AddPNode::Address)->is_Proj() && 2230 adr->in(AddPNode::Address)->in(0)->is_Allocate()) { 2231 // We are computing a raw address for a store captured by an Initialize 2232 // compute an appropriate address type. AddP cases #3 and #5 (see below). 2233 int offs = (int)phase->find_intptr_t_con(adr->in(AddPNode::Offset), Type::OffsetBot); 2234 assert(offs != Type::OffsetBot || 2235 adr->in(AddPNode::Address)->in(0)->is_AllocateArray(), 2236 "offset must be a constant or it is initialization of array"); 2237 return offs; 2238 } 2239 const TypePtr *t_ptr = adr_type->isa_ptr(); 2240 assert(t_ptr != NULL, "must be a pointer type"); 2241 return t_ptr->offset(); 2242 } 2243 2244 Node* ConnectionGraph::get_addp_base(Node *addp) { 2245 assert(addp->is_AddP(), "must be AddP"); 2246 // 2247 // AddP cases for Base and Address inputs: 2248 // case #1. Direct object's field reference: 2249 // Allocate 2250 // | 2251 // Proj #5 ( oop result ) 2252 // | 2253 // CheckCastPP (cast to instance type) 2254 // | | 2255 // AddP ( base == address ) 2256 // 2257 // case #2. Indirect object's field reference: 2258 // Phi 2259 // | 2260 // CastPP (cast to instance type) 2261 // | | 2262 // AddP ( base == address ) 2263 // 2264 // case #3. Raw object's field reference for Initialize node: 2265 // Allocate 2266 // | 2267 // Proj #5 ( oop result ) 2268 // top | 2269 // \ | 2270 // AddP ( base == top ) 2271 // 2272 // case #4. Array's element reference: 2273 // {CheckCastPP | CastPP} 2274 // | | | 2275 // | AddP ( array's element offset ) 2276 // | | 2277 // AddP ( array's offset ) 2278 // 2279 // case #5. Raw object's field reference for arraycopy stub call: 2280 // The inline_native_clone() case when the arraycopy stub is called 2281 // after the allocation before Initialize and CheckCastPP nodes. 2282 // Allocate 2283 // | 2284 // Proj #5 ( oop result ) 2285 // | | 2286 // AddP ( base == address ) 2287 // 2288 // case #6. Constant Pool, ThreadLocal, CastX2P or 2289 // Raw object's field reference: 2290 // {ConP, ThreadLocal, CastX2P, raw Load} 2291 // top | 2292 // \ | 2293 // AddP ( base == top ) 2294 // 2295 // case #7. Klass's field reference. 2296 // LoadKlass 2297 // | | 2298 // AddP ( base == address ) 2299 // 2300 // case #8. narrow Klass's field reference. 2301 // LoadNKlass 2302 // | 2303 // DecodeN 2304 // | | 2305 // AddP ( base == address ) 2306 // 2307 // case #9. Mixed unsafe access 2308 // {instance} 2309 // | 2310 // CheckCastPP (raw) 2311 // top | 2312 // \ | 2313 // AddP ( base == top ) 2314 // 2315 Node *base = addp->in(AddPNode::Base); 2316 if (base->uncast()->is_top()) { // The AddP case #3 and #6 and #9. 2317 base = addp->in(AddPNode::Address); 2318 while (base->is_AddP()) { 2319 // Case #6 (unsafe access) may have several chained AddP nodes. 2320 assert(base->in(AddPNode::Base)->uncast()->is_top(), "expected unsafe access address only"); 2321 base = base->in(AddPNode::Address); 2322 } 2323 if (base->Opcode() == Op_CheckCastPP && 2324 base->bottom_type()->isa_rawptr() && 2325 _igvn->type(base->in(1))->isa_oopptr()) { 2326 base = base->in(1); // Case #9 2327 } else { 2328 Node* uncast_base = base->uncast(); 2329 int opcode = uncast_base->Opcode(); 2330 assert(opcode == Op_ConP || opcode == Op_ThreadLocal || 2331 opcode == Op_CastX2P || uncast_base->is_DecodeNarrowPtr() || 2332 (uncast_base->is_Mem() && (uncast_base->bottom_type()->isa_rawptr() != NULL)) || 2333 (uncast_base->is_Proj() && uncast_base->in(0)->is_Allocate()), "sanity"); 2334 } 2335 } 2336 return base; 2337 } 2338 2339 Node* ConnectionGraph::find_second_addp(Node* addp, Node* n) { 2340 assert(addp->is_AddP() && addp->outcnt() > 0, "Don't process dead nodes"); 2341 Node* addp2 = addp->raw_out(0); 2342 if (addp->outcnt() == 1 && addp2->is_AddP() && 2343 addp2->in(AddPNode::Base) == n && 2344 addp2->in(AddPNode::Address) == addp) { 2345 assert(addp->in(AddPNode::Base) == n, "expecting the same base"); 2346 // 2347 // Find array's offset to push it on worklist first and 2348 // as result process an array's element offset first (pushed second) 2349 // to avoid CastPP for the array's offset. 2350 // Otherwise the inserted CastPP (LocalVar) will point to what 2351 // the AddP (Field) points to. Which would be wrong since 2352 // the algorithm expects the CastPP has the same point as 2353 // as AddP's base CheckCastPP (LocalVar). 2354 // 2355 // ArrayAllocation 2356 // | 2357 // CheckCastPP 2358 // | 2359 // memProj (from ArrayAllocation CheckCastPP) 2360 // | || 2361 // | || Int (element index) 2362 // | || | ConI (log(element size)) 2363 // | || | / 2364 // | || LShift 2365 // | || / 2366 // | AddP (array's element offset) 2367 // | | 2368 // | | ConI (array's offset: #12(32-bits) or #24(64-bits)) 2369 // | / / 2370 // AddP (array's offset) 2371 // | 2372 // Load/Store (memory operation on array's element) 2373 // 2374 return addp2; 2375 } 2376 return NULL; 2377 } 2378 2379 // 2380 // Adjust the type and inputs of an AddP which computes the 2381 // address of a field of an instance 2382 // 2383 bool ConnectionGraph::split_AddP(Node *addp, Node *base) { 2384 PhaseGVN* igvn = _igvn; 2385 const TypeOopPtr *base_t = igvn->type(base)->isa_oopptr(); 2386 assert(base_t != NULL && base_t->is_known_instance(), "expecting instance oopptr"); 2387 const TypeOopPtr *t = igvn->type(addp)->isa_oopptr(); 2388 if (t == NULL) { 2389 // We are computing a raw address for a store captured by an Initialize 2390 // compute an appropriate address type (cases #3 and #5). 2391 assert(igvn->type(addp) == TypeRawPtr::NOTNULL, "must be raw pointer"); 2392 assert(addp->in(AddPNode::Address)->is_Proj(), "base of raw address must be result projection from allocation"); 2393 intptr_t offs = (int)igvn->find_intptr_t_con(addp->in(AddPNode::Offset), Type::OffsetBot); 2394 assert(offs != Type::OffsetBot, "offset must be a constant"); 2395 t = base_t->add_offset(offs)->is_oopptr(); 2396 } 2397 int inst_id = base_t->instance_id(); 2398 assert(!t->is_known_instance() || t->instance_id() == inst_id, 2399 "old type must be non-instance or match new type"); 2400 2401 // The type 't' could be subclass of 'base_t'. 2402 // As result t->offset() could be large then base_t's size and it will 2403 // cause the failure in add_offset() with narrow oops since TypeOopPtr() 2404 // constructor verifies correctness of the offset. 2405 // 2406 // It could happened on subclass's branch (from the type profiling 2407 // inlining) which was not eliminated during parsing since the exactness 2408 // of the allocation type was not propagated to the subclass type check. 2409 // 2410 // Or the type 't' could be not related to 'base_t' at all. 2411 // It could happened when CHA type is different from MDO type on a dead path 2412 // (for example, from instanceof check) which is not collapsed during parsing. 2413 // 2414 // Do nothing for such AddP node and don't process its users since 2415 // this code branch will go away. 2416 // 2417 if (!t->is_known_instance() && 2418 !base_t->klass()->is_subtype_of(t->klass())) { 2419 return false; // bail out 2420 } 2421 const TypeOopPtr *tinst = base_t->add_offset(t->offset())->is_oopptr(); 2422 // Do NOT remove the next line: ensure a new alias index is allocated 2423 // for the instance type. Note: C++ will not remove it since the call 2424 // has side effect. 2425 int alias_idx = _compile->get_alias_index(tinst); 2426 igvn->set_type(addp, tinst); 2427 // record the allocation in the node map 2428 set_map(addp, get_map(base->_idx)); 2429 // Set addp's Base and Address to 'base'. 2430 Node *abase = addp->in(AddPNode::Base); 2431 Node *adr = addp->in(AddPNode::Address); 2432 if (adr->is_Proj() && adr->in(0)->is_Allocate() && 2433 adr->in(0)->_idx == (uint)inst_id) { 2434 // Skip AddP cases #3 and #5. 2435 } else { 2436 assert(!abase->is_top(), "sanity"); // AddP case #3 2437 if (abase != base) { 2438 igvn->hash_delete(addp); 2439 addp->set_req(AddPNode::Base, base); 2440 if (abase == adr) { 2441 addp->set_req(AddPNode::Address, base); 2442 } else { 2443 // AddP case #4 (adr is array's element offset AddP node) 2444 #ifdef ASSERT 2445 const TypeOopPtr *atype = igvn->type(adr)->isa_oopptr(); 2446 assert(adr->is_AddP() && atype != NULL && 2447 atype->instance_id() == inst_id, "array's element offset should be processed first"); 2448 #endif 2449 } 2450 igvn->hash_insert(addp); 2451 } 2452 } 2453 // Put on IGVN worklist since at least addp's type was changed above. 2454 record_for_optimizer(addp); 2455 return true; 2456 } 2457 2458 // 2459 // Create a new version of orig_phi if necessary. Returns either the newly 2460 // created phi or an existing phi. Sets create_new to indicate whether a new 2461 // phi was created. Cache the last newly created phi in the node map. 2462 // 2463 PhiNode *ConnectionGraph::create_split_phi(PhiNode *orig_phi, int alias_idx, GrowableArray<PhiNode *> &orig_phi_worklist, bool &new_created) { 2464 Compile *C = _compile; 2465 PhaseGVN* igvn = _igvn; 2466 new_created = false; 2467 int phi_alias_idx = C->get_alias_index(orig_phi->adr_type()); 2468 // nothing to do if orig_phi is bottom memory or matches alias_idx 2469 if (phi_alias_idx == alias_idx) { 2470 return orig_phi; 2471 } 2472 // Have we recently created a Phi for this alias index? 2473 PhiNode *result = get_map_phi(orig_phi->_idx); 2474 if (result != NULL && C->get_alias_index(result->adr_type()) == alias_idx) { 2475 return result; 2476 } 2477 // Previous check may fail when the same wide memory Phi was split into Phis 2478 // for different memory slices. Search all Phis for this region. 2479 if (result != NULL) { 2480 Node* region = orig_phi->in(0); 2481 for (DUIterator_Fast imax, i = region->fast_outs(imax); i < imax; i++) { 2482 Node* phi = region->fast_out(i); 2483 if (phi->is_Phi() && 2484 C->get_alias_index(phi->as_Phi()->adr_type()) == alias_idx) { 2485 assert(phi->_idx >= nodes_size(), "only new Phi per instance memory slice"); 2486 return phi->as_Phi(); 2487 } 2488 } 2489 } 2490 if (C->live_nodes() + 2*NodeLimitFudgeFactor > C->max_node_limit()) { 2491 if (C->do_escape_analysis() == true && !C->failing()) { 2492 // Retry compilation without escape analysis. 2493 // If this is the first failure, the sentinel string will "stick" 2494 // to the Compile object, and the C2Compiler will see it and retry. 2495 C->record_failure(C2Compiler::retry_no_escape_analysis()); 2496 } 2497 return NULL; 2498 } 2499 orig_phi_worklist.append_if_missing(orig_phi); 2500 const TypePtr *atype = C->get_adr_type(alias_idx); 2501 result = PhiNode::make(orig_phi->in(0), NULL, Type::MEMORY, atype); 2502 C->copy_node_notes_to(result, orig_phi); 2503 igvn->set_type(result, result->bottom_type()); 2504 record_for_optimizer(result); 2505 set_map(orig_phi, result); 2506 new_created = true; 2507 return result; 2508 } 2509 2510 // 2511 // Return a new version of Memory Phi "orig_phi" with the inputs having the 2512 // specified alias index. 2513 // 2514 PhiNode *ConnectionGraph::split_memory_phi(PhiNode *orig_phi, int alias_idx, GrowableArray<PhiNode *> &orig_phi_worklist) { 2515 assert(alias_idx != Compile::AliasIdxBot, "can't split out bottom memory"); 2516 Compile *C = _compile; 2517 PhaseGVN* igvn = _igvn; 2518 bool new_phi_created; 2519 PhiNode *result = create_split_phi(orig_phi, alias_idx, orig_phi_worklist, new_phi_created); 2520 if (!new_phi_created) { 2521 return result; 2522 } 2523 GrowableArray<PhiNode *> phi_list; 2524 GrowableArray<uint> cur_input; 2525 PhiNode *phi = orig_phi; 2526 uint idx = 1; 2527 bool finished = false; 2528 while(!finished) { 2529 while (idx < phi->req()) { 2530 Node *mem = find_inst_mem(phi->in(idx), alias_idx, orig_phi_worklist); 2531 if (mem != NULL && mem->is_Phi()) { 2532 PhiNode *newphi = create_split_phi(mem->as_Phi(), alias_idx, orig_phi_worklist, new_phi_created); 2533 if (new_phi_created) { 2534 // found an phi for which we created a new split, push current one on worklist and begin 2535 // processing new one 2536 phi_list.push(phi); 2537 cur_input.push(idx); 2538 phi = mem->as_Phi(); 2539 result = newphi; 2540 idx = 1; 2541 continue; 2542 } else { 2543 mem = newphi; 2544 } 2545 } 2546 if (C->failing()) { 2547 return NULL; 2548 } 2549 result->set_req(idx++, mem); 2550 } 2551 #ifdef ASSERT 2552 // verify that the new Phi has an input for each input of the original 2553 assert( phi->req() == result->req(), "must have same number of inputs."); 2554 assert( result->in(0) != NULL && result->in(0) == phi->in(0), "regions must match"); 2555 #endif 2556 // Check if all new phi's inputs have specified alias index. 2557 // Otherwise use old phi. 2558 for (uint i = 1; i < phi->req(); i++) { 2559 Node* in = result->in(i); 2560 assert((phi->in(i) == NULL) == (in == NULL), "inputs must correspond."); 2561 } 2562 // we have finished processing a Phi, see if there are any more to do 2563 finished = (phi_list.length() == 0 ); 2564 if (!finished) { 2565 phi = phi_list.pop(); 2566 idx = cur_input.pop(); 2567 PhiNode *prev_result = get_map_phi(phi->_idx); 2568 prev_result->set_req(idx++, result); 2569 result = prev_result; 2570 } 2571 } 2572 return result; 2573 } 2574 2575 // 2576 // The next methods are derived from methods in MemNode. 2577 // 2578 Node* ConnectionGraph::step_through_mergemem(MergeMemNode *mmem, int alias_idx, const TypeOopPtr *toop) { 2579 Node *mem = mmem; 2580 // TypeOopPtr::NOTNULL+any is an OOP with unknown offset - generally 2581 // means an array I have not precisely typed yet. Do not do any 2582 // alias stuff with it any time soon. 2583 if (toop->base() != Type::AnyPtr && 2584 !(toop->klass() != NULL && 2585 toop->klass()->is_java_lang_Object() && 2586 toop->offset() == Type::OffsetBot)) { 2587 mem = mmem->memory_at(alias_idx); 2588 // Update input if it is progress over what we have now 2589 } 2590 return mem; 2591 } 2592 2593 // 2594 // Move memory users to their memory slices. 2595 // 2596 void ConnectionGraph::move_inst_mem(Node* n, GrowableArray<PhiNode *> &orig_phis) { 2597 Compile* C = _compile; 2598 PhaseGVN* igvn = _igvn; 2599 const TypePtr* tp = igvn->type(n->in(MemNode::Address))->isa_ptr(); 2600 assert(tp != NULL, "ptr type"); 2601 int alias_idx = C->get_alias_index(tp); 2602 int general_idx = C->get_general_index(alias_idx); 2603 2604 // Move users first 2605 for (DUIterator_Fast imax, i = n->fast_outs(imax); i < imax; i++) { 2606 Node* use = n->fast_out(i); 2607 if (use->is_MergeMem()) { 2608 MergeMemNode* mmem = use->as_MergeMem(); 2609 assert(n == mmem->memory_at(alias_idx), "should be on instance memory slice"); 2610 if (n != mmem->memory_at(general_idx) || alias_idx == general_idx) { 2611 continue; // Nothing to do 2612 } 2613 // Replace previous general reference to mem node. 2614 uint orig_uniq = C->unique(); 2615 Node* m = find_inst_mem(n, general_idx, orig_phis); 2616 assert(orig_uniq == C->unique(), "no new nodes"); 2617 mmem->set_memory_at(general_idx, m); 2618 --imax; 2619 --i; 2620 } else if (use->is_MemBar()) { 2621 assert(!use->is_Initialize(), "initializing stores should not be moved"); 2622 if (use->req() > MemBarNode::Precedent && 2623 use->in(MemBarNode::Precedent) == n) { 2624 // Don't move related membars. 2625 record_for_optimizer(use); 2626 continue; 2627 } 2628 tp = use->as_MemBar()->adr_type()->isa_ptr(); 2629 if ((tp != NULL && C->get_alias_index(tp) == alias_idx) || 2630 alias_idx == general_idx) { 2631 continue; // Nothing to do 2632 } 2633 // Move to general memory slice. 2634 uint orig_uniq = C->unique(); 2635 Node* m = find_inst_mem(n, general_idx, orig_phis); 2636 assert(orig_uniq == C->unique(), "no new nodes"); 2637 igvn->hash_delete(use); 2638 imax -= use->replace_edge(n, m); 2639 igvn->hash_insert(use); 2640 record_for_optimizer(use); 2641 --i; 2642 #ifdef ASSERT 2643 } else if (use->is_Mem()) { 2644 if (use->Opcode() == Op_StoreCM && use->in(MemNode::OopStore) == n) { 2645 // Don't move related cardmark. 2646 continue; 2647 } 2648 // Memory nodes should have new memory input. 2649 tp = igvn->type(use->in(MemNode::Address))->isa_ptr(); 2650 assert(tp != NULL, "ptr type"); 2651 int idx = C->get_alias_index(tp); 2652 assert(get_map(use->_idx) != NULL || idx == alias_idx, 2653 "Following memory nodes should have new memory input or be on the same memory slice"); 2654 } else if (use->is_Phi()) { 2655 // Phi nodes should be split and moved already. 2656 tp = use->as_Phi()->adr_type()->isa_ptr(); 2657 assert(tp != NULL, "ptr type"); 2658 int idx = C->get_alias_index(tp); 2659 assert(idx == alias_idx, "Following Phi nodes should be on the same memory slice"); 2660 } else { 2661 use->dump(); 2662 assert(false, "should not be here"); 2663 #endif 2664 } 2665 } 2666 } 2667 2668 // 2669 // Search memory chain of "mem" to find a MemNode whose address 2670 // is the specified alias index. 2671 // 2672 Node* ConnectionGraph::find_inst_mem(Node *orig_mem, int alias_idx, GrowableArray<PhiNode *> &orig_phis) { 2673 if (orig_mem == NULL) 2674 return orig_mem; 2675 Compile* C = _compile; 2676 PhaseGVN* igvn = _igvn; 2677 const TypeOopPtr *toop = C->get_adr_type(alias_idx)->isa_oopptr(); 2678 bool is_instance = (toop != NULL) && toop->is_known_instance(); 2679 Node *start_mem = C->start()->proj_out_or_null(TypeFunc::Memory); 2680 Node *prev = NULL; 2681 Node *result = orig_mem; 2682 while (prev != result) { 2683 prev = result; 2684 if (result == start_mem) 2685 break; // hit one of our sentinels 2686 if (result->is_Mem()) { 2687 const Type *at = igvn->type(result->in(MemNode::Address)); 2688 if (at == Type::TOP) 2689 break; // Dead 2690 assert (at->isa_ptr() != NULL, "pointer type required."); 2691 int idx = C->get_alias_index(at->is_ptr()); 2692 if (idx == alias_idx) 2693 break; // Found 2694 if (!is_instance && (at->isa_oopptr() == NULL || 2695 !at->is_oopptr()->is_known_instance())) { 2696 break; // Do not skip store to general memory slice. 2697 } 2698 result = result->in(MemNode::Memory); 2699 } 2700 if (!is_instance) 2701 continue; // don't search further for non-instance types 2702 // skip over a call which does not affect this memory slice 2703 if (result->is_Proj() && result->as_Proj()->_con == TypeFunc::Memory) { 2704 Node *proj_in = result->in(0); 2705 if (proj_in->is_Allocate() && proj_in->_idx == (uint)toop->instance_id()) { 2706 break; // hit one of our sentinels 2707 } else if (proj_in->is_Call()) { 2708 // ArrayCopy node processed here as well 2709 CallNode *call = proj_in->as_Call(); 2710 if (!call->may_modify(toop, igvn)) { 2711 result = call->in(TypeFunc::Memory); 2712 } 2713 } else if (proj_in->is_Initialize()) { 2714 AllocateNode* alloc = proj_in->as_Initialize()->allocation(); 2715 // Stop if this is the initialization for the object instance which 2716 // which contains this memory slice, otherwise skip over it. 2717 if (alloc == NULL || alloc->_idx != (uint)toop->instance_id()) { 2718 result = proj_in->in(TypeFunc::Memory); 2719 } 2720 } else if (proj_in->is_MemBar()) { 2721 if (proj_in->in(TypeFunc::Memory)->is_MergeMem() && 2722 proj_in->in(TypeFunc::Memory)->as_MergeMem()->in(Compile::AliasIdxRaw)->is_Proj() && 2723 proj_in->in(TypeFunc::Memory)->as_MergeMem()->in(Compile::AliasIdxRaw)->in(0)->is_ArrayCopy()) { 2724 // clone 2725 ArrayCopyNode* ac = proj_in->in(TypeFunc::Memory)->as_MergeMem()->in(Compile::AliasIdxRaw)->in(0)->as_ArrayCopy(); 2726 if (ac->may_modify(toop, igvn)) { 2727 break; 2728 } 2729 } 2730 result = proj_in->in(TypeFunc::Memory); 2731 } 2732 } else if (result->is_MergeMem()) { 2733 MergeMemNode *mmem = result->as_MergeMem(); 2734 result = step_through_mergemem(mmem, alias_idx, toop); 2735 if (result == mmem->base_memory()) { 2736 // Didn't find instance memory, search through general slice recursively. 2737 result = mmem->memory_at(C->get_general_index(alias_idx)); 2738 result = find_inst_mem(result, alias_idx, orig_phis); 2739 if (C->failing()) { 2740 return NULL; 2741 } 2742 mmem->set_memory_at(alias_idx, result); 2743 } 2744 } else if (result->is_Phi() && 2745 C->get_alias_index(result->as_Phi()->adr_type()) != alias_idx) { 2746 Node *un = result->as_Phi()->unique_input(igvn); 2747 if (un != NULL) { 2748 orig_phis.append_if_missing(result->as_Phi()); 2749 result = un; 2750 } else { 2751 break; 2752 } 2753 } else if (result->is_ClearArray()) { 2754 if (!ClearArrayNode::step_through(&result, (uint)toop->instance_id(), igvn)) { 2755 // Can not bypass initialization of the instance 2756 // we are looking for. 2757 break; 2758 } 2759 // Otherwise skip it (the call updated 'result' value). 2760 } else if (result->Opcode() == Op_SCMemProj) { 2761 Node* mem = result->in(0); 2762 Node* adr = NULL; 2763 if (mem->is_LoadStore()) { 2764 adr = mem->in(MemNode::Address); 2765 } else { 2766 assert(mem->Opcode() == Op_EncodeISOArray || 2767 mem->Opcode() == Op_StrCompressedCopy, "sanity"); 2768 adr = mem->in(3); // Memory edge corresponds to destination array 2769 } 2770 const Type *at = igvn->type(adr); 2771 if (at != Type::TOP) { 2772 assert(at->isa_ptr() != NULL, "pointer type required."); 2773 int idx = C->get_alias_index(at->is_ptr()); 2774 if (idx == alias_idx) { 2775 // Assert in debug mode 2776 assert(false, "Object is not scalar replaceable if a LoadStore node accesses its field"); 2777 break; // In product mode return SCMemProj node 2778 } 2779 } 2780 result = mem->in(MemNode::Memory); 2781 } else if (result->Opcode() == Op_StrInflatedCopy) { 2782 Node* adr = result->in(3); // Memory edge corresponds to destination array 2783 const Type *at = igvn->type(adr); 2784 if (at != Type::TOP) { 2785 assert(at->isa_ptr() != NULL, "pointer type required."); 2786 int idx = C->get_alias_index(at->is_ptr()); 2787 if (idx == alias_idx) { 2788 // Assert in debug mode 2789 assert(false, "Object is not scalar replaceable if a StrInflatedCopy node accesses its field"); 2790 break; // In product mode return SCMemProj node 2791 } 2792 } 2793 result = result->in(MemNode::Memory); 2794 } 2795 } 2796 if (result->is_Phi()) { 2797 PhiNode *mphi = result->as_Phi(); 2798 assert(mphi->bottom_type() == Type::MEMORY, "memory phi required"); 2799 const TypePtr *t = mphi->adr_type(); 2800 if (!is_instance) { 2801 // Push all non-instance Phis on the orig_phis worklist to update inputs 2802 // during Phase 4 if needed. 2803 orig_phis.append_if_missing(mphi); 2804 } else if (C->get_alias_index(t) != alias_idx) { 2805 // Create a new Phi with the specified alias index type. 2806 result = split_memory_phi(mphi, alias_idx, orig_phis); 2807 } 2808 } 2809 // the result is either MemNode, PhiNode, InitializeNode. 2810 return result; 2811 } 2812 2813 // 2814 // Convert the types of unescaped object to instance types where possible, 2815 // propagate the new type information through the graph, and update memory 2816 // edges and MergeMem inputs to reflect the new type. 2817 // 2818 // We start with allocations (and calls which may be allocations) on alloc_worklist. 2819 // The processing is done in 4 phases: 2820 // 2821 // Phase 1: Process possible allocations from alloc_worklist. Create instance 2822 // types for the CheckCastPP for allocations where possible. 2823 // Propagate the new types through users as follows: 2824 // casts and Phi: push users on alloc_worklist 2825 // AddP: cast Base and Address inputs to the instance type 2826 // push any AddP users on alloc_worklist and push any memnode 2827 // users onto memnode_worklist. 2828 // Phase 2: Process MemNode's from memnode_worklist. compute new address type and 2829 // search the Memory chain for a store with the appropriate type 2830 // address type. If a Phi is found, create a new version with 2831 // the appropriate memory slices from each of the Phi inputs. 2832 // For stores, process the users as follows: 2833 // MemNode: push on memnode_worklist 2834 // MergeMem: push on mergemem_worklist 2835 // Phase 3: Process MergeMem nodes from mergemem_worklist. Walk each memory slice 2836 // moving the first node encountered of each instance type to the 2837 // the input corresponding to its alias index. 2838 // appropriate memory slice. 2839 // Phase 4: Update the inputs of non-instance memory Phis and the Memory input of memnodes. 2840 // 2841 // In the following example, the CheckCastPP nodes are the cast of allocation 2842 // results and the allocation of node 29 is unescaped and eligible to be an 2843 // instance type. 2844 // 2845 // We start with: 2846 // 2847 // 7 Parm #memory 2848 // 10 ConI "12" 2849 // 19 CheckCastPP "Foo" 2850 // 20 AddP _ 19 19 10 Foo+12 alias_index=4 2851 // 29 CheckCastPP "Foo" 2852 // 30 AddP _ 29 29 10 Foo+12 alias_index=4 2853 // 2854 // 40 StoreP 25 7 20 ... alias_index=4 2855 // 50 StoreP 35 40 30 ... alias_index=4 2856 // 60 StoreP 45 50 20 ... alias_index=4 2857 // 70 LoadP _ 60 30 ... alias_index=4 2858 // 80 Phi 75 50 60 Memory alias_index=4 2859 // 90 LoadP _ 80 30 ... alias_index=4 2860 // 100 LoadP _ 80 20 ... alias_index=4 2861 // 2862 // 2863 // Phase 1 creates an instance type for node 29 assigning it an instance id of 24 2864 // and creating a new alias index for node 30. This gives: 2865 // 2866 // 7 Parm #memory 2867 // 10 ConI "12" 2868 // 19 CheckCastPP "Foo" 2869 // 20 AddP _ 19 19 10 Foo+12 alias_index=4 2870 // 29 CheckCastPP "Foo" iid=24 2871 // 30 AddP _ 29 29 10 Foo+12 alias_index=6 iid=24 2872 // 2873 // 40 StoreP 25 7 20 ... alias_index=4 2874 // 50 StoreP 35 40 30 ... alias_index=6 2875 // 60 StoreP 45 50 20 ... alias_index=4 2876 // 70 LoadP _ 60 30 ... alias_index=6 2877 // 80 Phi 75 50 60 Memory alias_index=4 2878 // 90 LoadP _ 80 30 ... alias_index=6 2879 // 100 LoadP _ 80 20 ... alias_index=4 2880 // 2881 // In phase 2, new memory inputs are computed for the loads and stores, 2882 // And a new version of the phi is created. In phase 4, the inputs to 2883 // node 80 are updated and then the memory nodes are updated with the 2884 // values computed in phase 2. This results in: 2885 // 2886 // 7 Parm #memory 2887 // 10 ConI "12" 2888 // 19 CheckCastPP "Foo" 2889 // 20 AddP _ 19 19 10 Foo+12 alias_index=4 2890 // 29 CheckCastPP "Foo" iid=24 2891 // 30 AddP _ 29 29 10 Foo+12 alias_index=6 iid=24 2892 // 2893 // 40 StoreP 25 7 20 ... alias_index=4 2894 // 50 StoreP 35 7 30 ... alias_index=6 2895 // 60 StoreP 45 40 20 ... alias_index=4 2896 // 70 LoadP _ 50 30 ... alias_index=6 2897 // 80 Phi 75 40 60 Memory alias_index=4 2898 // 120 Phi 75 50 50 Memory alias_index=6 2899 // 90 LoadP _ 120 30 ... alias_index=6 2900 // 100 LoadP _ 80 20 ... alias_index=4 2901 // 2902 void ConnectionGraph::split_unique_types(GrowableArray<Node *> &alloc_worklist, GrowableArray<ArrayCopyNode*> &arraycopy_worklist) { 2903 GrowableArray<Node *> memnode_worklist; 2904 GrowableArray<PhiNode *> orig_phis; 2905 PhaseIterGVN *igvn = _igvn; 2906 uint new_index_start = (uint) _compile->num_alias_types(); 2907 Arena* arena = Thread::current()->resource_area(); 2908 VectorSet visited(arena); 2909 ideal_nodes.clear(); // Reset for use with set_map/get_map. 2910 uint unique_old = _compile->unique(); 2911 2912 // Phase 1: Process possible allocations from alloc_worklist. 2913 // Create instance types for the CheckCastPP for allocations where possible. 2914 // 2915 // (Note: don't forget to change the order of the second AddP node on 2916 // the alloc_worklist if the order of the worklist processing is changed, 2917 // see the comment in find_second_addp().) 2918 // 2919 while (alloc_worklist.length() != 0) { 2920 Node *n = alloc_worklist.pop(); 2921 uint ni = n->_idx; 2922 if (n->is_Call()) { 2923 CallNode *alloc = n->as_Call(); 2924 // copy escape information to call node 2925 PointsToNode* ptn = ptnode_adr(alloc->_idx); 2926 PointsToNode::EscapeState es = ptn->escape_state(); 2927 // We have an allocation or call which returns a Java object, 2928 // see if it is unescaped. 2929 if (es != PointsToNode::NoEscape || !ptn->scalar_replaceable()) 2930 continue; 2931 // Find CheckCastPP for the allocate or for the return value of a call 2932 n = alloc->result_cast(); 2933 if (n == NULL) { // No uses except Initialize node 2934 if (alloc->is_Allocate()) { 2935 // Set the scalar_replaceable flag for allocation 2936 // so it could be eliminated if it has no uses. 2937 alloc->as_Allocate()->_is_scalar_replaceable = true; 2938 } 2939 if (alloc->is_CallStaticJava()) { 2940 // Set the scalar_replaceable flag for boxing method 2941 // so it could be eliminated if it has no uses. 2942 alloc->as_CallStaticJava()->_is_scalar_replaceable = true; 2943 } 2944 continue; 2945 } 2946 if (!n->is_CheckCastPP()) { // not unique CheckCastPP. 2947 assert(!alloc->is_Allocate(), "allocation should have unique type"); 2948 continue; 2949 } 2950 2951 // The inline code for Object.clone() casts the allocation result to 2952 // java.lang.Object and then to the actual type of the allocated 2953 // object. Detect this case and use the second cast. 2954 // Also detect j.l.reflect.Array.newInstance(jobject, jint) case when 2955 // the allocation result is cast to java.lang.Object and then 2956 // to the actual Array type. 2957 if (alloc->is_Allocate() && n->as_Type()->type() == TypeInstPtr::NOTNULL 2958 && (alloc->is_AllocateArray() || 2959 igvn->type(alloc->in(AllocateNode::KlassNode)) != TypeKlassPtr::OBJECT)) { 2960 Node *cast2 = NULL; 2961 for (DUIterator_Fast imax, i = n->fast_outs(imax); i < imax; i++) { 2962 Node *use = n->fast_out(i); 2963 if (use->is_CheckCastPP()) { 2964 cast2 = use; 2965 break; 2966 } 2967 } 2968 if (cast2 != NULL) { 2969 n = cast2; 2970 } else { 2971 // Non-scalar replaceable if the allocation type is unknown statically 2972 // (reflection allocation), the object can't be restored during 2973 // deoptimization without precise type. 2974 continue; 2975 } 2976 } 2977 2978 const TypeOopPtr *t = igvn->type(n)->isa_oopptr(); 2979 if (t == NULL) 2980 continue; // not a TypeOopPtr 2981 if (!t->klass_is_exact()) 2982 continue; // not an unique type 2983 2984 if (alloc->is_Allocate()) { 2985 // Set the scalar_replaceable flag for allocation 2986 // so it could be eliminated. 2987 alloc->as_Allocate()->_is_scalar_replaceable = true; 2988 } 2989 if (alloc->is_CallStaticJava()) { 2990 // Set the scalar_replaceable flag for boxing method 2991 // so it could be eliminated. 2992 alloc->as_CallStaticJava()->_is_scalar_replaceable = true; 2993 } 2994 set_escape_state(ptnode_adr(n->_idx), es); // CheckCastPP escape state 2995 // in order for an object to be scalar-replaceable, it must be: 2996 // - a direct allocation (not a call returning an object) 2997 // - non-escaping 2998 // - eligible to be a unique type 2999 // - not determined to be ineligible by escape analysis 3000 set_map(alloc, n); 3001 set_map(n, alloc); 3002 const TypeOopPtr* tinst = t->cast_to_instance_id(ni); 3003 igvn->hash_delete(n); 3004 igvn->set_type(n, tinst); 3005 n->raise_bottom_type(tinst); 3006 igvn->hash_insert(n); 3007 record_for_optimizer(n); 3008 if (alloc->is_Allocate() && (t->isa_instptr() || t->isa_aryptr())) { 3009 3010 // First, put on the worklist all Field edges from Connection Graph 3011 // which is more accurate than putting immediate users from Ideal Graph. 3012 for (EdgeIterator e(ptn); e.has_next(); e.next()) { 3013 PointsToNode* tgt = e.get(); 3014 if (tgt->is_Arraycopy()) { 3015 continue; 3016 } 3017 Node* use = tgt->ideal_node(); 3018 assert(tgt->is_Field() && use->is_AddP(), 3019 "only AddP nodes are Field edges in CG"); 3020 if (use->outcnt() > 0) { // Don't process dead nodes 3021 Node* addp2 = find_second_addp(use, use->in(AddPNode::Base)); 3022 if (addp2 != NULL) { 3023 assert(alloc->is_AllocateArray(),"array allocation was expected"); 3024 alloc_worklist.append_if_missing(addp2); 3025 } 3026 alloc_worklist.append_if_missing(use); 3027 } 3028 } 3029 3030 // An allocation may have an Initialize which has raw stores. Scan 3031 // the users of the raw allocation result and push AddP users 3032 // on alloc_worklist. 3033 Node *raw_result = alloc->proj_out_or_null(TypeFunc::Parms); 3034 assert (raw_result != NULL, "must have an allocation result"); 3035 for (DUIterator_Fast imax, i = raw_result->fast_outs(imax); i < imax; i++) { 3036 Node *use = raw_result->fast_out(i); 3037 if (use->is_AddP() && use->outcnt() > 0) { // Don't process dead nodes 3038 Node* addp2 = find_second_addp(use, raw_result); 3039 if (addp2 != NULL) { 3040 assert(alloc->is_AllocateArray(),"array allocation was expected"); 3041 alloc_worklist.append_if_missing(addp2); 3042 } 3043 alloc_worklist.append_if_missing(use); 3044 } else if (use->is_MemBar()) { 3045 memnode_worklist.append_if_missing(use); 3046 } 3047 } 3048 } 3049 } else if (n->is_AddP()) { 3050 JavaObjectNode* jobj = unique_java_object(get_addp_base(n)); 3051 if (jobj == NULL || jobj == phantom_obj) { 3052 #ifdef ASSERT 3053 ptnode_adr(get_addp_base(n)->_idx)->dump(); 3054 ptnode_adr(n->_idx)->dump(); 3055 assert(jobj != NULL && jobj != phantom_obj, "escaped allocation"); 3056 #endif 3057 _compile->record_failure(C2Compiler::retry_no_escape_analysis()); 3058 return; 3059 } 3060 Node *base = get_map(jobj->idx()); // CheckCastPP node 3061 if (!split_AddP(n, base)) continue; // wrong type from dead path 3062 } else if (n->is_Phi() || 3063 n->is_CheckCastPP() || 3064 n->is_EncodeP() || 3065 n->is_DecodeN() || 3066 (n->is_ConstraintCast() && n->Opcode() == Op_CastPP)) { 3067 if (visited.test_set(n->_idx)) { 3068 assert(n->is_Phi(), "loops only through Phi's"); 3069 continue; // already processed 3070 } 3071 JavaObjectNode* jobj = unique_java_object(n); 3072 if (jobj == NULL || jobj == phantom_obj) { 3073 #ifdef ASSERT 3074 ptnode_adr(n->_idx)->dump(); 3075 assert(jobj != NULL && jobj != phantom_obj, "escaped allocation"); 3076 #endif 3077 _compile->record_failure(C2Compiler::retry_no_escape_analysis()); 3078 return; 3079 } else { 3080 Node *val = get_map(jobj->idx()); // CheckCastPP node 3081 TypeNode *tn = n->as_Type(); 3082 const TypeOopPtr* tinst = igvn->type(val)->isa_oopptr(); 3083 assert(tinst != NULL && tinst->is_known_instance() && 3084 tinst->instance_id() == jobj->idx() , "instance type expected."); 3085 3086 const Type *tn_type = igvn->type(tn); 3087 const TypeOopPtr *tn_t; 3088 if (tn_type->isa_narrowoop()) { 3089 tn_t = tn_type->make_ptr()->isa_oopptr(); 3090 } else { 3091 tn_t = tn_type->isa_oopptr(); 3092 } 3093 if (tn_t != NULL && tinst->klass()->is_subtype_of(tn_t->klass())) { 3094 if (tn_type->isa_narrowoop()) { 3095 tn_type = tinst->make_narrowoop(); 3096 } else { 3097 tn_type = tinst; 3098 } 3099 igvn->hash_delete(tn); 3100 igvn->set_type(tn, tn_type); 3101 tn->set_type(tn_type); 3102 igvn->hash_insert(tn); 3103 record_for_optimizer(n); 3104 } else { 3105 assert(tn_type == TypePtr::NULL_PTR || 3106 tn_t != NULL && !tinst->klass()->is_subtype_of(tn_t->klass()), 3107 "unexpected type"); 3108 continue; // Skip dead path with different type 3109 } 3110 } 3111 } else { 3112 debug_only(n->dump();) 3113 assert(false, "EA: unexpected node"); 3114 continue; 3115 } 3116 // push allocation's users on appropriate worklist 3117 for (DUIterator_Fast imax, i = n->fast_outs(imax); i < imax; i++) { 3118 Node *use = n->fast_out(i); 3119 if(use->is_Mem() && use->in(MemNode::Address) == n) { 3120 // Load/store to instance's field 3121 memnode_worklist.append_if_missing(use); 3122 } else if (use->is_MemBar()) { 3123 if (use->in(TypeFunc::Memory) == n) { // Ignore precedent edge 3124 memnode_worklist.append_if_missing(use); 3125 } 3126 } else if (use->is_AddP() && use->outcnt() > 0) { // No dead nodes 3127 Node* addp2 = find_second_addp(use, n); 3128 if (addp2 != NULL) { 3129 alloc_worklist.append_if_missing(addp2); 3130 } 3131 alloc_worklist.append_if_missing(use); 3132 } else if (use->is_Phi() || 3133 use->is_CheckCastPP() || 3134 use->is_EncodeNarrowPtr() || 3135 use->is_DecodeNarrowPtr() || 3136 (use->is_ConstraintCast() && use->Opcode() == Op_CastPP)) { 3137 alloc_worklist.append_if_missing(use); 3138 #ifdef ASSERT 3139 } else if (use->is_Mem()) { 3140 assert(use->in(MemNode::Address) != n, "EA: missing allocation reference path"); 3141 } else if (use->is_MergeMem()) { 3142 assert(_mergemem_worklist.contains(use->as_MergeMem()), "EA: missing MergeMem node in the worklist"); 3143 } else if (use->is_SafePoint()) { 3144 // Look for MergeMem nodes for calls which reference unique allocation 3145 // (through CheckCastPP nodes) even for debug info. 3146 Node* m = use->in(TypeFunc::Memory); 3147 if (m->is_MergeMem()) { 3148 assert(_mergemem_worklist.contains(m->as_MergeMem()), "EA: missing MergeMem node in the worklist"); 3149 } 3150 } else if (use->Opcode() == Op_EncodeISOArray) { 3151 if (use->in(MemNode::Memory) == n || use->in(3) == n) { 3152 // EncodeISOArray overwrites destination array 3153 memnode_worklist.append_if_missing(use); 3154 } 3155 } else { 3156 uint op = use->Opcode(); 3157 if ((op == Op_StrCompressedCopy || op == Op_StrInflatedCopy) && 3158 (use->in(MemNode::Memory) == n)) { 3159 // They overwrite memory edge corresponding to destination array, 3160 memnode_worklist.append_if_missing(use); 3161 } else if (!(op == Op_CmpP || op == Op_Conv2B || 3162 op == Op_CastP2X || op == Op_StoreCM || 3163 op == Op_FastLock || op == Op_AryEq || op == Op_StrComp || op == Op_HasNegatives || 3164 op == Op_StrCompressedCopy || op == Op_StrInflatedCopy || 3165 op == Op_StrEquals || op == Op_StrIndexOf || op == Op_StrIndexOfChar)) { 3166 n->dump(); 3167 use->dump(); 3168 assert(false, "EA: missing allocation reference path"); 3169 } 3170 #endif 3171 } 3172 } 3173 3174 } 3175 3176 // Go over all ArrayCopy nodes and if one of the inputs has a unique 3177 // type, record it in the ArrayCopy node so we know what memory this 3178 // node uses/modified. 3179 for (int next = 0; next < arraycopy_worklist.length(); next++) { 3180 ArrayCopyNode* ac = arraycopy_worklist.at(next); 3181 Node* dest = ac->in(ArrayCopyNode::Dest); 3182 if (dest->is_AddP()) { 3183 dest = get_addp_base(dest); 3184 } 3185 JavaObjectNode* jobj = unique_java_object(dest); 3186 if (jobj != NULL) { 3187 Node *base = get_map(jobj->idx()); 3188 if (base != NULL) { 3189 const TypeOopPtr *base_t = _igvn->type(base)->isa_oopptr(); 3190 ac->_dest_type = base_t; 3191 } 3192 } 3193 Node* src = ac->in(ArrayCopyNode::Src); 3194 if (src->is_AddP()) { 3195 src = get_addp_base(src); 3196 } 3197 jobj = unique_java_object(src); 3198 if (jobj != NULL) { 3199 Node* base = get_map(jobj->idx()); 3200 if (base != NULL) { 3201 const TypeOopPtr *base_t = _igvn->type(base)->isa_oopptr(); 3202 ac->_src_type = base_t; 3203 } 3204 } 3205 } 3206 3207 // New alias types were created in split_AddP(). 3208 uint new_index_end = (uint) _compile->num_alias_types(); 3209 assert(unique_old == _compile->unique(), "there should be no new ideal nodes after Phase 1"); 3210 3211 // Phase 2: Process MemNode's from memnode_worklist. compute new address type and 3212 // compute new values for Memory inputs (the Memory inputs are not 3213 // actually updated until phase 4.) 3214 if (memnode_worklist.length() == 0) 3215 return; // nothing to do 3216 while (memnode_worklist.length() != 0) { 3217 Node *n = memnode_worklist.pop(); 3218 if (visited.test_set(n->_idx)) 3219 continue; 3220 if (n->is_Phi() || n->is_ClearArray()) { 3221 // we don't need to do anything, but the users must be pushed 3222 } else if (n->is_MemBar()) { // Initialize, MemBar nodes 3223 // we don't need to do anything, but the users must be pushed 3224 n = n->as_MemBar()->proj_out_or_null(TypeFunc::Memory); 3225 if (n == NULL) 3226 continue; 3227 } else if (n->Opcode() == Op_StrCompressedCopy || 3228 n->Opcode() == Op_EncodeISOArray) { 3229 // get the memory projection 3230 n = n->find_out_with(Op_SCMemProj); 3231 assert(n != NULL && n->Opcode() == Op_SCMemProj, "memory projection required"); 3232 } else { 3233 assert(n->is_Mem(), "memory node required."); 3234 Node *addr = n->in(MemNode::Address); 3235 const Type *addr_t = igvn->type(addr); 3236 if (addr_t == Type::TOP) 3237 continue; 3238 assert (addr_t->isa_ptr() != NULL, "pointer type required."); 3239 int alias_idx = _compile->get_alias_index(addr_t->is_ptr()); 3240 assert ((uint)alias_idx < new_index_end, "wrong alias index"); 3241 Node *mem = find_inst_mem(n->in(MemNode::Memory), alias_idx, orig_phis); 3242 if (_compile->failing()) { 3243 return; 3244 } 3245 if (mem != n->in(MemNode::Memory)) { 3246 // We delay the memory edge update since we need old one in 3247 // MergeMem code below when instances memory slices are separated. 3248 set_map(n, mem); 3249 } 3250 if (n->is_Load()) { 3251 continue; // don't push users 3252 } else if (n->is_LoadStore()) { 3253 // get the memory projection 3254 n = n->find_out_with(Op_SCMemProj); 3255 assert(n != NULL && n->Opcode() == Op_SCMemProj, "memory projection required"); 3256 } 3257 } 3258 // push user on appropriate worklist 3259 for (DUIterator_Fast imax, i = n->fast_outs(imax); i < imax; i++) { 3260 Node *use = n->fast_out(i); 3261 if (use->is_Phi() || use->is_ClearArray()) { 3262 memnode_worklist.append_if_missing(use); 3263 } else if (use->is_Mem() && use->in(MemNode::Memory) == n) { 3264 if (use->Opcode() == Op_StoreCM) // Ignore cardmark stores 3265 continue; 3266 memnode_worklist.append_if_missing(use); 3267 } else if (use->is_MemBar()) { 3268 if (use->in(TypeFunc::Memory) == n) { // Ignore precedent edge 3269 memnode_worklist.append_if_missing(use); 3270 } 3271 #ifdef ASSERT 3272 } else if(use->is_Mem()) { 3273 assert(use->in(MemNode::Memory) != n, "EA: missing memory path"); 3274 } else if (use->is_MergeMem()) { 3275 assert(_mergemem_worklist.contains(use->as_MergeMem()), "EA: missing MergeMem node in the worklist"); 3276 } else if (use->Opcode() == Op_EncodeISOArray) { 3277 if (use->in(MemNode::Memory) == n || use->in(3) == n) { 3278 // EncodeISOArray overwrites destination array 3279 memnode_worklist.append_if_missing(use); 3280 } 3281 } else { 3282 uint op = use->Opcode(); 3283 if ((use->in(MemNode::Memory) == n) && 3284 (op == Op_StrCompressedCopy || op == Op_StrInflatedCopy)) { 3285 // They overwrite memory edge corresponding to destination array, 3286 memnode_worklist.append_if_missing(use); 3287 } else if (!(op == Op_StoreCM || 3288 (op == Op_CallLeaf && use->as_CallLeaf()->_name != NULL && 3289 strcmp(use->as_CallLeaf()->_name, "g1_wb_pre") == 0) || 3290 op == Op_AryEq || op == Op_StrComp || op == Op_HasNegatives || 3291 op == Op_StrCompressedCopy || op == Op_StrInflatedCopy || 3292 op == Op_StrEquals || op == Op_StrIndexOf || op == Op_StrIndexOfChar)) { 3293 n->dump(); 3294 use->dump(); 3295 assert(false, "EA: missing memory path"); 3296 } 3297 #endif 3298 } 3299 } 3300 } 3301 3302 // Phase 3: Process MergeMem nodes from mergemem_worklist. 3303 // Walk each memory slice moving the first node encountered of each 3304 // instance type to the the input corresponding to its alias index. 3305 uint length = _mergemem_worklist.length(); 3306 for( uint next = 0; next < length; ++next ) { 3307 MergeMemNode* nmm = _mergemem_worklist.at(next); 3308 assert(!visited.test_set(nmm->_idx), "should not be visited before"); 3309 // Note: we don't want to use MergeMemStream here because we only want to 3310 // scan inputs which exist at the start, not ones we add during processing. 3311 // Note 2: MergeMem may already contains instance memory slices added 3312 // during find_inst_mem() call when memory nodes were processed above. 3313 igvn->hash_delete(nmm); 3314 uint nslices = MIN2(nmm->req(), new_index_start); 3315 for (uint i = Compile::AliasIdxRaw+1; i < nslices; i++) { 3316 Node* mem = nmm->in(i); 3317 Node* cur = NULL; 3318 if (mem == NULL || mem->is_top()) 3319 continue; 3320 // First, update mergemem by moving memory nodes to corresponding slices 3321 // if their type became more precise since this mergemem was created. 3322 while (mem->is_Mem()) { 3323 const Type *at = igvn->type(mem->in(MemNode::Address)); 3324 if (at != Type::TOP) { 3325 assert (at->isa_ptr() != NULL, "pointer type required."); 3326 uint idx = (uint)_compile->get_alias_index(at->is_ptr()); 3327 if (idx == i) { 3328 if (cur == NULL) 3329 cur = mem; 3330 } else { 3331 if (idx >= nmm->req() || nmm->is_empty_memory(nmm->in(idx))) { 3332 nmm->set_memory_at(idx, mem); 3333 } 3334 } 3335 } 3336 mem = mem->in(MemNode::Memory); 3337 } 3338 nmm->set_memory_at(i, (cur != NULL) ? cur : mem); 3339 // Find any instance of the current type if we haven't encountered 3340 // already a memory slice of the instance along the memory chain. 3341 for (uint ni = new_index_start; ni < new_index_end; ni++) { 3342 if((uint)_compile->get_general_index(ni) == i) { 3343 Node *m = (ni >= nmm->req()) ? nmm->empty_memory() : nmm->in(ni); 3344 if (nmm->is_empty_memory(m)) { 3345 Node* result = find_inst_mem(mem, ni, orig_phis); 3346 if (_compile->failing()) { 3347 return; 3348 } 3349 nmm->set_memory_at(ni, result); 3350 } 3351 } 3352 } 3353 } 3354 // Find the rest of instances values 3355 for (uint ni = new_index_start; ni < new_index_end; ni++) { 3356 const TypeOopPtr *tinst = _compile->get_adr_type(ni)->isa_oopptr(); 3357 Node* result = step_through_mergemem(nmm, ni, tinst); 3358 if (result == nmm->base_memory()) { 3359 // Didn't find instance memory, search through general slice recursively. 3360 result = nmm->memory_at(_compile->get_general_index(ni)); 3361 result = find_inst_mem(result, ni, orig_phis); 3362 if (_compile->failing()) { 3363 return; 3364 } 3365 nmm->set_memory_at(ni, result); 3366 } 3367 } 3368 igvn->hash_insert(nmm); 3369 record_for_optimizer(nmm); 3370 } 3371 3372 // Phase 4: Update the inputs of non-instance memory Phis and 3373 // the Memory input of memnodes 3374 // First update the inputs of any non-instance Phi's from 3375 // which we split out an instance Phi. Note we don't have 3376 // to recursively process Phi's encounted on the input memory 3377 // chains as is done in split_memory_phi() since they will 3378 // also be processed here. 3379 for (int j = 0; j < orig_phis.length(); j++) { 3380 PhiNode *phi = orig_phis.at(j); 3381 int alias_idx = _compile->get_alias_index(phi->adr_type()); 3382 igvn->hash_delete(phi); 3383 for (uint i = 1; i < phi->req(); i++) { 3384 Node *mem = phi->in(i); 3385 Node *new_mem = find_inst_mem(mem, alias_idx, orig_phis); 3386 if (_compile->failing()) { 3387 return; 3388 } 3389 if (mem != new_mem) { 3390 phi->set_req(i, new_mem); 3391 } 3392 } 3393 igvn->hash_insert(phi); 3394 record_for_optimizer(phi); 3395 } 3396 3397 // Update the memory inputs of MemNodes with the value we computed 3398 // in Phase 2 and move stores memory users to corresponding memory slices. 3399 // Disable memory split verification code until the fix for 6984348. 3400 // Currently it produces false negative results since it does not cover all cases. 3401 #if 0 // ifdef ASSERT 3402 visited.Reset(); 3403 Node_Stack old_mems(arena, _compile->unique() >> 2); 3404 #endif 3405 for (uint i = 0; i < ideal_nodes.size(); i++) { 3406 Node* n = ideal_nodes.at(i); 3407 Node* nmem = get_map(n->_idx); 3408 assert(nmem != NULL, "sanity"); 3409 if (n->is_Mem()) { 3410 #if 0 // ifdef ASSERT 3411 Node* old_mem = n->in(MemNode::Memory); 3412 if (!visited.test_set(old_mem->_idx)) { 3413 old_mems.push(old_mem, old_mem->outcnt()); 3414 } 3415 #endif 3416 assert(n->in(MemNode::Memory) != nmem, "sanity"); 3417 if (!n->is_Load()) { 3418 // Move memory users of a store first. 3419 move_inst_mem(n, orig_phis); 3420 } 3421 // Now update memory input 3422 igvn->hash_delete(n); 3423 n->set_req(MemNode::Memory, nmem); 3424 igvn->hash_insert(n); 3425 record_for_optimizer(n); 3426 } else { 3427 assert(n->is_Allocate() || n->is_CheckCastPP() || 3428 n->is_AddP() || n->is_Phi(), "unknown node used for set_map()"); 3429 } 3430 } 3431 #if 0 // ifdef ASSERT 3432 // Verify that memory was split correctly 3433 while (old_mems.is_nonempty()) { 3434 Node* old_mem = old_mems.node(); 3435 uint old_cnt = old_mems.index(); 3436 old_mems.pop(); 3437 assert(old_cnt == old_mem->outcnt(), "old mem could be lost"); 3438 } 3439 #endif 3440 } 3441 3442 #ifndef PRODUCT 3443 static const char *node_type_names[] = { 3444 "UnknownType", 3445 "JavaObject", 3446 "LocalVar", 3447 "Field", 3448 "Arraycopy" 3449 }; 3450 3451 static const char *esc_names[] = { 3452 "UnknownEscape", 3453 "NoEscape", 3454 "ArgEscape", 3455 "GlobalEscape" 3456 }; 3457 3458 void PointsToNode::dump(bool print_state) const { 3459 NodeType nt = node_type(); 3460 tty->print("%s ", node_type_names[(int) nt]); 3461 if (print_state) { 3462 EscapeState es = escape_state(); 3463 EscapeState fields_es = fields_escape_state(); 3464 tty->print("%s(%s) ", esc_names[(int)es], esc_names[(int)fields_es]); 3465 if (nt == PointsToNode::JavaObject && !this->scalar_replaceable()) 3466 tty->print("NSR "); 3467 } 3468 if (is_Field()) { 3469 FieldNode* f = (FieldNode*)this; 3470 if (f->is_oop()) 3471 tty->print("oop "); 3472 if (f->offset() > 0) 3473 tty->print("+%d ", f->offset()); 3474 tty->print("("); 3475 for (BaseIterator i(f); i.has_next(); i.next()) { 3476 PointsToNode* b = i.get(); 3477 tty->print(" %d%s", b->idx(),(b->is_JavaObject() ? "P" : "")); 3478 } 3479 tty->print(" )"); 3480 } 3481 tty->print("["); 3482 for (EdgeIterator i(this); i.has_next(); i.next()) { 3483 PointsToNode* e = i.get(); 3484 tty->print(" %d%s%s", e->idx(),(e->is_JavaObject() ? "P" : (e->is_Field() ? "F" : "")), e->is_Arraycopy() ? "cp" : ""); 3485 } 3486 tty->print(" ["); 3487 for (UseIterator i(this); i.has_next(); i.next()) { 3488 PointsToNode* u = i.get(); 3489 bool is_base = false; 3490 if (PointsToNode::is_base_use(u)) { 3491 is_base = true; 3492 u = PointsToNode::get_use_node(u)->as_Field(); 3493 } 3494 tty->print(" %d%s%s", u->idx(), is_base ? "b" : "", u->is_Arraycopy() ? "cp" : ""); 3495 } 3496 tty->print(" ]] "); 3497 if (_node == NULL) 3498 tty->print_cr("<null>"); 3499 else 3500 _node->dump(); 3501 } 3502 3503 void ConnectionGraph::dump(GrowableArray<PointsToNode*>& ptnodes_worklist) { 3504 bool first = true; 3505 int ptnodes_length = ptnodes_worklist.length(); 3506 for (int i = 0; i < ptnodes_length; i++) { 3507 PointsToNode *ptn = ptnodes_worklist.at(i); 3508 if (ptn == NULL || !ptn->is_JavaObject()) 3509 continue; 3510 PointsToNode::EscapeState es = ptn->escape_state(); 3511 if ((es != PointsToNode::NoEscape) && !Verbose) { 3512 continue; 3513 } 3514 Node* n = ptn->ideal_node(); 3515 if (n->is_Allocate() || (n->is_CallStaticJava() && 3516 n->as_CallStaticJava()->is_boxing_method())) { 3517 if (first) { 3518 tty->cr(); 3519 tty->print("======== Connection graph for "); 3520 _compile->method()->print_short_name(); 3521 tty->cr(); 3522 first = false; 3523 } 3524 ptn->dump(); 3525 // Print all locals and fields which reference this allocation 3526 for (UseIterator j(ptn); j.has_next(); j.next()) { 3527 PointsToNode* use = j.get(); 3528 if (use->is_LocalVar()) { 3529 use->dump(Verbose); 3530 } else if (Verbose) { 3531 use->dump(); 3532 } 3533 } 3534 tty->cr(); 3535 } 3536 } 3537 } 3538 #endif