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_G1GC 41 #include "gc/g1/g1ThreadLocalData.hpp" 42 #endif // INCLUDE_G1GC 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 INCLUDE_G1GC 542 if (UseG1GC && adr->is_AddP()) { 543 Node* base = get_addp_base(adr); 544 if (base->Opcode() == Op_LoadP && 545 base->in(MemNode::Address)->is_AddP()) { 546 adr = base->in(MemNode::Address); 547 Node* tls = get_addp_base(adr); 548 if (tls->Opcode() == Op_ThreadLocal) { 549 int offs = (int)igvn->find_intptr_t_con(adr->in(AddPNode::Offset), Type::OffsetBot); 550 if (offs == in_bytes(G1ThreadLocalData::satb_mark_queue_buffer_offset())) { 551 break; // G1 pre barrier previous oop value store. 552 } 553 if (offs == in_bytes(G1ThreadLocalData::dirty_card_queue_buffer_offset())) { 554 break; // G1 post barrier card address store. 555 } 556 } 557 } 558 } 559 #endif 560 delayed_worklist->push(n); // Process unsafe access later. 561 break; 562 } 563 #ifdef ASSERT 564 n->dump(1); 565 assert(false, "not unsafe or G1 barrier raw StoreP"); 566 #endif 567 } 568 break; 569 } 570 case Op_AryEq: 571 case Op_HasNegatives: 572 case Op_StrComp: 573 case Op_StrEquals: 574 case Op_StrIndexOf: 575 case Op_StrIndexOfChar: 576 case Op_StrInflatedCopy: 577 case Op_StrCompressedCopy: 578 case Op_EncodeISOArray: { 579 add_local_var(n, PointsToNode::ArgEscape); 580 delayed_worklist->push(n); // Process it later. 581 break; 582 } 583 case Op_ThreadLocal: { 584 add_java_object(n, PointsToNode::ArgEscape); 585 break; 586 } 587 default: 588 ; // Do nothing for nodes not related to EA. 589 } 590 return; 591 } 592 593 #ifdef ASSERT 594 #define ELSE_FAIL(name) \ 595 /* Should not be called for not pointer type. */ \ 596 n->dump(1); \ 597 assert(false, name); \ 598 break; 599 #else 600 #define ELSE_FAIL(name) \ 601 break; 602 #endif 603 604 // Add final simple edges to graph. 605 void ConnectionGraph::add_final_edges(Node *n) { 606 PointsToNode* n_ptn = ptnode_adr(n->_idx); 607 #ifdef ASSERT 608 if (_verify && n_ptn->is_JavaObject()) 609 return; // This method does not change graph for JavaObject. 610 #endif 611 612 if (n->is_Call()) { 613 process_call_arguments(n->as_Call()); 614 return; 615 } 616 assert(n->is_Store() || n->is_LoadStore() || 617 (n_ptn != NULL) && (n_ptn->ideal_node() != NULL), 618 "node should be registered already"); 619 int opcode = n->Opcode(); 620 switch (opcode) { 621 case Op_AddP: { 622 Node* base = get_addp_base(n); 623 PointsToNode* ptn_base = ptnode_adr(base->_idx); 624 assert(ptn_base != NULL, "field's base should be registered"); 625 add_base(n_ptn->as_Field(), ptn_base); 626 break; 627 } 628 case Op_CastPP: 629 case Op_CheckCastPP: 630 case Op_EncodeP: 631 case Op_DecodeN: 632 case Op_EncodePKlass: 633 case Op_DecodeNKlass: { 634 add_local_var_and_edge(n, PointsToNode::NoEscape, 635 n->in(1), NULL); 636 break; 637 } 638 case Op_CMoveP: { 639 for (uint i = CMoveNode::IfFalse; i < n->req(); i++) { 640 Node* in = n->in(i); 641 if (in == NULL) 642 continue; // ignore NULL 643 Node* uncast_in = in->uncast(); 644 if (uncast_in->is_top() || uncast_in == n) 645 continue; // ignore top or inputs which go back this node 646 PointsToNode* ptn = ptnode_adr(in->_idx); 647 assert(ptn != NULL, "node should be registered"); 648 add_edge(n_ptn, ptn); 649 } 650 break; 651 } 652 case Op_LoadP: 653 case Op_LoadN: 654 case Op_LoadPLocked: { 655 // Using isa_ptr() instead of isa_oopptr() for LoadP and Phi because 656 // ThreadLocal has RawPtr type. 657 const Type* t = _igvn->type(n); 658 if (t->make_ptr() != NULL) { 659 Node* adr = n->in(MemNode::Address); 660 add_local_var_and_edge(n, PointsToNode::NoEscape, adr, NULL); 661 break; 662 } 663 ELSE_FAIL("Op_LoadP"); 664 } 665 case Op_Phi: { 666 // Using isa_ptr() instead of isa_oopptr() for LoadP and Phi because 667 // ThreadLocal has RawPtr type. 668 const Type* t = n->as_Phi()->type(); 669 if (t->make_ptr() != NULL) { 670 for (uint i = 1; i < n->req(); i++) { 671 Node* in = n->in(i); 672 if (in == NULL) 673 continue; // ignore NULL 674 Node* uncast_in = in->uncast(); 675 if (uncast_in->is_top() || uncast_in == n) 676 continue; // ignore top or inputs which go back this node 677 PointsToNode* ptn = ptnode_adr(in->_idx); 678 assert(ptn != NULL, "node should be registered"); 679 add_edge(n_ptn, ptn); 680 } 681 break; 682 } 683 ELSE_FAIL("Op_Phi"); 684 } 685 case Op_Proj: { 686 // we are only interested in the oop result projection from a call 687 if (n->as_Proj()->_con == TypeFunc::Parms && n->in(0)->is_Call() && 688 n->in(0)->as_Call()->returns_pointer()) { 689 add_local_var_and_edge(n, PointsToNode::NoEscape, n->in(0), NULL); 690 break; 691 } 692 ELSE_FAIL("Op_Proj"); 693 } 694 case Op_Rethrow: // Exception object escapes 695 case Op_Return: { 696 if (n->req() > TypeFunc::Parms && 697 _igvn->type(n->in(TypeFunc::Parms))->isa_oopptr()) { 698 // Treat Return value as LocalVar with GlobalEscape escape state. 699 add_local_var_and_edge(n, PointsToNode::GlobalEscape, 700 n->in(TypeFunc::Parms), NULL); 701 break; 702 } 703 ELSE_FAIL("Op_Return"); 704 } 705 case Op_StoreP: 706 case Op_StoreN: 707 case Op_StoreNKlass: 708 case Op_StorePConditional: 709 case Op_CompareAndExchangeP: 710 case Op_CompareAndExchangeN: 711 case Op_CompareAndSwapP: 712 case Op_CompareAndSwapN: 713 case Op_WeakCompareAndSwapP: 714 case Op_WeakCompareAndSwapN: 715 case Op_GetAndSetP: 716 case Op_GetAndSetN: { 717 Node* adr = n->in(MemNode::Address); 718 const Type *adr_type = _igvn->type(adr); 719 adr_type = adr_type->make_ptr(); 720 #ifdef ASSERT 721 if (adr_type == NULL) { 722 n->dump(1); 723 assert(adr_type != NULL, "dead node should not be on list"); 724 break; 725 } 726 #endif 727 if (opcode == Op_GetAndSetP || opcode == Op_GetAndSetN || 728 opcode == Op_CompareAndExchangeN || opcode == Op_CompareAndExchangeP) { 729 add_local_var_and_edge(n, PointsToNode::NoEscape, adr, NULL); 730 } 731 if ( adr_type->isa_oopptr() 732 || ( (opcode == Op_StoreP || opcode == Op_StoreN || opcode == Op_StoreNKlass) 733 && adr_type == TypeRawPtr::NOTNULL 734 && adr->in(AddPNode::Address)->is_Proj() 735 && adr->in(AddPNode::Address)->in(0)->is_Allocate())) { 736 // Point Address to Value 737 PointsToNode* adr_ptn = ptnode_adr(adr->_idx); 738 assert(adr_ptn != NULL && 739 adr_ptn->as_Field()->is_oop(), "node should be registered"); 740 Node *val = n->in(MemNode::ValueIn); 741 PointsToNode* ptn = ptnode_adr(val->_idx); 742 assert(ptn != NULL, "node should be registered"); 743 add_edge(adr_ptn, ptn); 744 break; 745 } else if ((opcode == Op_StoreP) && adr_type->isa_rawptr()) { 746 // Stored value escapes in unsafe access. 747 Node *val = n->in(MemNode::ValueIn); 748 PointsToNode* ptn = ptnode_adr(val->_idx); 749 assert(ptn != NULL, "node should be registered"); 750 set_escape_state(ptn, PointsToNode::GlobalEscape); 751 // Add edge to object for unsafe access with offset. 752 PointsToNode* adr_ptn = ptnode_adr(adr->_idx); 753 assert(adr_ptn != NULL, "node should be registered"); 754 if (adr_ptn->is_Field()) { 755 assert(adr_ptn->as_Field()->is_oop(), "should be oop field"); 756 add_edge(adr_ptn, ptn); 757 } 758 break; 759 } 760 ELSE_FAIL("Op_StoreP"); 761 } 762 case Op_AryEq: 763 case Op_HasNegatives: 764 case Op_StrComp: 765 case Op_StrEquals: 766 case Op_StrIndexOf: 767 case Op_StrIndexOfChar: 768 case Op_StrInflatedCopy: 769 case Op_StrCompressedCopy: 770 case Op_EncodeISOArray: { 771 // char[]/byte[] arrays passed to string intrinsic do not escape but 772 // they are not scalar replaceable. Adjust escape state for them. 773 // Start from in(2) edge since in(1) is memory edge. 774 for (uint i = 2; i < n->req(); i++) { 775 Node* adr = n->in(i); 776 const Type* at = _igvn->type(adr); 777 if (!adr->is_top() && at->isa_ptr()) { 778 assert(at == Type::TOP || at == TypePtr::NULL_PTR || 779 at->isa_ptr() != NULL, "expecting a pointer"); 780 if (adr->is_AddP()) { 781 adr = get_addp_base(adr); 782 } 783 PointsToNode* ptn = ptnode_adr(adr->_idx); 784 assert(ptn != NULL, "node should be registered"); 785 add_edge(n_ptn, ptn); 786 } 787 } 788 break; 789 } 790 default: { 791 // This method should be called only for EA specific nodes which may 792 // miss some edges when they were created. 793 #ifdef ASSERT 794 n->dump(1); 795 #endif 796 guarantee(false, "unknown node"); 797 } 798 } 799 return; 800 } 801 802 void ConnectionGraph::add_call_node(CallNode* call) { 803 assert(call->returns_pointer(), "only for call which returns pointer"); 804 uint call_idx = call->_idx; 805 if (call->is_Allocate()) { 806 Node* k = call->in(AllocateNode::KlassNode); 807 const TypeKlassPtr* kt = k->bottom_type()->isa_klassptr(); 808 assert(kt != NULL, "TypeKlassPtr required."); 809 ciKlass* cik = kt->klass(); 810 PointsToNode::EscapeState es = PointsToNode::NoEscape; 811 bool scalar_replaceable = true; 812 if (call->is_AllocateArray()) { 813 if (!cik->is_array_klass()) { // StressReflectiveCode 814 es = PointsToNode::GlobalEscape; 815 } else { 816 int length = call->in(AllocateNode::ALength)->find_int_con(-1); 817 if (length < 0 || length > EliminateAllocationArraySizeLimit) { 818 // Not scalar replaceable if the length is not constant or too big. 819 scalar_replaceable = false; 820 } 821 } 822 } else { // Allocate instance 823 if (cik->is_subclass_of(_compile->env()->Thread_klass()) || 824 cik->is_subclass_of(_compile->env()->Reference_klass()) || 825 !cik->is_instance_klass() || // StressReflectiveCode 826 !cik->as_instance_klass()->can_be_instantiated() || 827 cik->as_instance_klass()->has_finalizer()) { 828 es = PointsToNode::GlobalEscape; 829 } 830 } 831 add_java_object(call, es); 832 PointsToNode* ptn = ptnode_adr(call_idx); 833 if (!scalar_replaceable && ptn->scalar_replaceable()) { 834 ptn->set_scalar_replaceable(false); 835 } 836 } else if (call->is_CallStaticJava()) { 837 // Call nodes could be different types: 838 // 839 // 1. CallDynamicJavaNode (what happened during call is unknown): 840 // 841 // - mapped to GlobalEscape JavaObject node if oop is returned; 842 // 843 // - all oop arguments are escaping globally; 844 // 845 // 2. CallStaticJavaNode (execute bytecode analysis if possible): 846 // 847 // - the same as CallDynamicJavaNode if can't do bytecode analysis; 848 // 849 // - mapped to GlobalEscape JavaObject node if unknown oop is returned; 850 // - mapped to NoEscape JavaObject node if non-escaping object allocated 851 // during call is returned; 852 // - mapped to ArgEscape LocalVar node pointed to object arguments 853 // which are returned and does not escape during call; 854 // 855 // - oop arguments escaping status is defined by bytecode analysis; 856 // 857 // For a static call, we know exactly what method is being called. 858 // Use bytecode estimator to record whether the call's return value escapes. 859 ciMethod* meth = call->as_CallJava()->method(); 860 if (meth == NULL) { 861 const char* name = call->as_CallStaticJava()->_name; 862 assert(strncmp(name, "_multianewarray", 15) == 0, "TODO: add failed case check"); 863 // Returns a newly allocated unescaped object. 864 add_java_object(call, PointsToNode::NoEscape); 865 ptnode_adr(call_idx)->set_scalar_replaceable(false); 866 } else if (meth->is_boxing_method()) { 867 // Returns boxing object 868 PointsToNode::EscapeState es; 869 vmIntrinsics::ID intr = meth->intrinsic_id(); 870 if (intr == vmIntrinsics::_floatValue || intr == vmIntrinsics::_doubleValue) { 871 // It does not escape if object is always allocated. 872 es = PointsToNode::NoEscape; 873 } else { 874 // It escapes globally if object could be loaded from cache. 875 es = PointsToNode::GlobalEscape; 876 } 877 add_java_object(call, es); 878 } else { 879 BCEscapeAnalyzer* call_analyzer = meth->get_bcea(); 880 call_analyzer->copy_dependencies(_compile->dependencies()); 881 if (call_analyzer->is_return_allocated()) { 882 // Returns a newly allocated unescaped object, simply 883 // update dependency information. 884 // Mark it as NoEscape so that objects referenced by 885 // it's fields will be marked as NoEscape at least. 886 add_java_object(call, PointsToNode::NoEscape); 887 ptnode_adr(call_idx)->set_scalar_replaceable(false); 888 } else { 889 // Determine whether any arguments are returned. 890 const TypeTuple* d = call->tf()->domain(); 891 bool ret_arg = false; 892 for (uint i = TypeFunc::Parms; i < d->cnt(); i++) { 893 if (d->field_at(i)->isa_ptr() != NULL && 894 call_analyzer->is_arg_returned(i - TypeFunc::Parms)) { 895 ret_arg = true; 896 break; 897 } 898 } 899 if (ret_arg) { 900 add_local_var(call, PointsToNode::ArgEscape); 901 } else { 902 // Returns unknown object. 903 map_ideal_node(call, phantom_obj); 904 } 905 } 906 } 907 } else { 908 // An other type of call, assume the worst case: 909 // returned value is unknown and globally escapes. 910 assert(call->Opcode() == Op_CallDynamicJava, "add failed case check"); 911 map_ideal_node(call, phantom_obj); 912 } 913 } 914 915 void ConnectionGraph::process_call_arguments(CallNode *call) { 916 bool is_arraycopy = false; 917 switch (call->Opcode()) { 918 #ifdef ASSERT 919 case Op_Allocate: 920 case Op_AllocateArray: 921 case Op_Lock: 922 case Op_Unlock: 923 assert(false, "should be done already"); 924 break; 925 #endif 926 case Op_ArrayCopy: 927 case Op_CallLeafNoFP: 928 // Most array copies are ArrayCopy nodes at this point but there 929 // are still a few direct calls to the copy subroutines (See 930 // PhaseStringOpts::copy_string()) 931 is_arraycopy = (call->Opcode() == Op_ArrayCopy) || 932 call->as_CallLeaf()->is_call_to_arraycopystub(); 933 // fall through 934 case Op_CallLeaf: { 935 // Stub calls, objects do not escape but they are not scale replaceable. 936 // Adjust escape state for outgoing arguments. 937 const TypeTuple * d = call->tf()->domain(); 938 bool src_has_oops = false; 939 for (uint i = TypeFunc::Parms; i < d->cnt(); i++) { 940 const Type* at = d->field_at(i); 941 Node *arg = call->in(i); 942 if (arg == NULL) { 943 continue; 944 } 945 const Type *aat = _igvn->type(arg); 946 if (arg->is_top() || !at->isa_ptr() || !aat->isa_ptr()) 947 continue; 948 if (arg->is_AddP()) { 949 // 950 // The inline_native_clone() case when the arraycopy stub is called 951 // after the allocation before Initialize and CheckCastPP nodes. 952 // Or normal arraycopy for object arrays case. 953 // 954 // Set AddP's base (Allocate) as not scalar replaceable since 955 // pointer to the base (with offset) is passed as argument. 956 // 957 arg = get_addp_base(arg); 958 } 959 PointsToNode* arg_ptn = ptnode_adr(arg->_idx); 960 assert(arg_ptn != NULL, "should be registered"); 961 PointsToNode::EscapeState arg_esc = arg_ptn->escape_state(); 962 if (is_arraycopy || arg_esc < PointsToNode::ArgEscape) { 963 assert(aat == Type::TOP || aat == TypePtr::NULL_PTR || 964 aat->isa_ptr() != NULL, "expecting an Ptr"); 965 bool arg_has_oops = aat->isa_oopptr() && 966 (aat->isa_oopptr()->klass() == NULL || aat->isa_instptr() || 967 (aat->isa_aryptr() && aat->isa_aryptr()->klass()->is_obj_array_klass())); 968 if (i == TypeFunc::Parms) { 969 src_has_oops = arg_has_oops; 970 } 971 // 972 // src or dst could be j.l.Object when other is basic type array: 973 // 974 // arraycopy(char[],0,Object*,0,size); 975 // arraycopy(Object*,0,char[],0,size); 976 // 977 // Don't add edges in such cases. 978 // 979 bool arg_is_arraycopy_dest = src_has_oops && is_arraycopy && 980 arg_has_oops && (i > TypeFunc::Parms); 981 #ifdef ASSERT 982 if (!(is_arraycopy || 983 (call->as_CallLeaf()->_name != NULL && 984 (strcmp(call->as_CallLeaf()->_name, "g1_wb_pre") == 0 || 985 strcmp(call->as_CallLeaf()->_name, "g1_wb_post") == 0 || 986 strcmp(call->as_CallLeaf()->_name, "updateBytesCRC32") == 0 || 987 strcmp(call->as_CallLeaf()->_name, "updateBytesCRC32C") == 0 || 988 strcmp(call->as_CallLeaf()->_name, "updateBytesAdler32") == 0 || 989 strcmp(call->as_CallLeaf()->_name, "aescrypt_encryptBlock") == 0 || 990 strcmp(call->as_CallLeaf()->_name, "aescrypt_decryptBlock") == 0 || 991 strcmp(call->as_CallLeaf()->_name, "cipherBlockChaining_encryptAESCrypt") == 0 || 992 strcmp(call->as_CallLeaf()->_name, "cipherBlockChaining_decryptAESCrypt") == 0 || 993 strcmp(call->as_CallLeaf()->_name, "counterMode_AESCrypt") == 0 || 994 strcmp(call->as_CallLeaf()->_name, "ghash_processBlocks") == 0 || 995 strcmp(call->as_CallLeaf()->_name, "sha1_implCompress") == 0 || 996 strcmp(call->as_CallLeaf()->_name, "sha1_implCompressMB") == 0 || 997 strcmp(call->as_CallLeaf()->_name, "sha256_implCompress") == 0 || 998 strcmp(call->as_CallLeaf()->_name, "sha256_implCompressMB") == 0 || 999 strcmp(call->as_CallLeaf()->_name, "sha512_implCompress") == 0 || 1000 strcmp(call->as_CallLeaf()->_name, "sha512_implCompressMB") == 0 || 1001 strcmp(call->as_CallLeaf()->_name, "multiplyToLen") == 0 || 1002 strcmp(call->as_CallLeaf()->_name, "squareToLen") == 0 || 1003 strcmp(call->as_CallLeaf()->_name, "mulAdd") == 0 || 1004 strcmp(call->as_CallLeaf()->_name, "montgomery_multiply") == 0 || 1005 strcmp(call->as_CallLeaf()->_name, "montgomery_square") == 0 || 1006 strcmp(call->as_CallLeaf()->_name, "vectorizedMismatch") == 0) 1007 ))) { 1008 call->dump(); 1009 fatal("EA unexpected CallLeaf %s", call->as_CallLeaf()->_name); 1010 } 1011 #endif 1012 // Always process arraycopy's destination object since 1013 // we need to add all possible edges to references in 1014 // source object. 1015 if (arg_esc >= PointsToNode::ArgEscape && 1016 !arg_is_arraycopy_dest) { 1017 continue; 1018 } 1019 PointsToNode::EscapeState es = PointsToNode::ArgEscape; 1020 if (call->is_ArrayCopy()) { 1021 ArrayCopyNode* ac = call->as_ArrayCopy(); 1022 if (ac->is_clonebasic() || 1023 ac->is_arraycopy_validated() || 1024 ac->is_copyof_validated() || 1025 ac->is_copyofrange_validated()) { 1026 es = PointsToNode::NoEscape; 1027 } 1028 } 1029 set_escape_state(arg_ptn, es); 1030 if (arg_is_arraycopy_dest) { 1031 Node* src = call->in(TypeFunc::Parms); 1032 if (src->is_AddP()) { 1033 src = get_addp_base(src); 1034 } 1035 PointsToNode* src_ptn = ptnode_adr(src->_idx); 1036 assert(src_ptn != NULL, "should be registered"); 1037 if (arg_ptn != src_ptn) { 1038 // Special arraycopy edge: 1039 // A destination object's field can't have the source object 1040 // as base since objects escape states are not related. 1041 // Only escape state of destination object's fields affects 1042 // escape state of fields in source object. 1043 add_arraycopy(call, es, src_ptn, arg_ptn); 1044 } 1045 } 1046 } 1047 } 1048 break; 1049 } 1050 case Op_CallStaticJava: { 1051 // For a static call, we know exactly what method is being called. 1052 // Use bytecode estimator to record the call's escape affects 1053 #ifdef ASSERT 1054 const char* name = call->as_CallStaticJava()->_name; 1055 assert((name == NULL || strcmp(name, "uncommon_trap") != 0), "normal calls only"); 1056 #endif 1057 ciMethod* meth = call->as_CallJava()->method(); 1058 if ((meth != NULL) && meth->is_boxing_method()) { 1059 break; // Boxing methods do not modify any oops. 1060 } 1061 BCEscapeAnalyzer* call_analyzer = (meth !=NULL) ? meth->get_bcea() : NULL; 1062 // fall-through if not a Java method or no analyzer information 1063 if (call_analyzer != NULL) { 1064 PointsToNode* call_ptn = ptnode_adr(call->_idx); 1065 const TypeTuple* d = call->tf()->domain(); 1066 for (uint i = TypeFunc::Parms; i < d->cnt(); i++) { 1067 const Type* at = d->field_at(i); 1068 int k = i - TypeFunc::Parms; 1069 Node* arg = call->in(i); 1070 PointsToNode* arg_ptn = ptnode_adr(arg->_idx); 1071 if (at->isa_ptr() != NULL && 1072 call_analyzer->is_arg_returned(k)) { 1073 // The call returns arguments. 1074 if (call_ptn != NULL) { // Is call's result used? 1075 assert(call_ptn->is_LocalVar(), "node should be registered"); 1076 assert(arg_ptn != NULL, "node should be registered"); 1077 add_edge(call_ptn, arg_ptn); 1078 } 1079 } 1080 if (at->isa_oopptr() != NULL && 1081 arg_ptn->escape_state() < PointsToNode::GlobalEscape) { 1082 if (!call_analyzer->is_arg_stack(k)) { 1083 // The argument global escapes 1084 set_escape_state(arg_ptn, PointsToNode::GlobalEscape); 1085 } else { 1086 set_escape_state(arg_ptn, PointsToNode::ArgEscape); 1087 if (!call_analyzer->is_arg_local(k)) { 1088 // The argument itself doesn't escape, but any fields might 1089 set_fields_escape_state(arg_ptn, PointsToNode::GlobalEscape); 1090 } 1091 } 1092 } 1093 } 1094 if (call_ptn != NULL && call_ptn->is_LocalVar()) { 1095 // The call returns arguments. 1096 assert(call_ptn->edge_count() > 0, "sanity"); 1097 if (!call_analyzer->is_return_local()) { 1098 // Returns also unknown object. 1099 add_edge(call_ptn, phantom_obj); 1100 } 1101 } 1102 break; 1103 } 1104 } 1105 default: { 1106 // Fall-through here if not a Java method or no analyzer information 1107 // or some other type of call, assume the worst case: all arguments 1108 // globally escape. 1109 const TypeTuple* d = call->tf()->domain(); 1110 for (uint i = TypeFunc::Parms; i < d->cnt(); i++) { 1111 const Type* at = d->field_at(i); 1112 if (at->isa_oopptr() != NULL) { 1113 Node* arg = call->in(i); 1114 if (arg->is_AddP()) { 1115 arg = get_addp_base(arg); 1116 } 1117 assert(ptnode_adr(arg->_idx) != NULL, "should be defined already"); 1118 set_escape_state(ptnode_adr(arg->_idx), PointsToNode::GlobalEscape); 1119 } 1120 } 1121 } 1122 } 1123 } 1124 1125 1126 // Finish Graph construction. 1127 bool ConnectionGraph::complete_connection_graph( 1128 GrowableArray<PointsToNode*>& ptnodes_worklist, 1129 GrowableArray<JavaObjectNode*>& non_escaped_worklist, 1130 GrowableArray<JavaObjectNode*>& java_objects_worklist, 1131 GrowableArray<FieldNode*>& oop_fields_worklist) { 1132 // Normally only 1-3 passes needed to build Connection Graph depending 1133 // on graph complexity. Observed 8 passes in jvm2008 compiler.compiler. 1134 // Set limit to 20 to catch situation when something did go wrong and 1135 // bailout Escape Analysis. 1136 // Also limit build time to 20 sec (60 in debug VM), EscapeAnalysisTimeout flag. 1137 #define CG_BUILD_ITER_LIMIT 20 1138 1139 // Propagate GlobalEscape and ArgEscape escape states and check that 1140 // we still have non-escaping objects. The method pushs on _worklist 1141 // Field nodes which reference phantom_object. 1142 if (!find_non_escaped_objects(ptnodes_worklist, non_escaped_worklist)) { 1143 return false; // Nothing to do. 1144 } 1145 // Now propagate references to all JavaObject nodes. 1146 int java_objects_length = java_objects_worklist.length(); 1147 elapsedTimer time; 1148 bool timeout = false; 1149 int new_edges = 1; 1150 int iterations = 0; 1151 do { 1152 while ((new_edges > 0) && 1153 (iterations++ < CG_BUILD_ITER_LIMIT)) { 1154 double start_time = time.seconds(); 1155 time.start(); 1156 new_edges = 0; 1157 // Propagate references to phantom_object for nodes pushed on _worklist 1158 // by find_non_escaped_objects() and find_field_value(). 1159 new_edges += add_java_object_edges(phantom_obj, false); 1160 for (int next = 0; next < java_objects_length; ++next) { 1161 JavaObjectNode* ptn = java_objects_worklist.at(next); 1162 new_edges += add_java_object_edges(ptn, true); 1163 1164 #define SAMPLE_SIZE 4 1165 if ((next % SAMPLE_SIZE) == 0) { 1166 // Each 4 iterations calculate how much time it will take 1167 // to complete graph construction. 1168 time.stop(); 1169 // Poll for requests from shutdown mechanism to quiesce compiler 1170 // because Connection graph construction may take long time. 1171 CompileBroker::maybe_block(); 1172 double stop_time = time.seconds(); 1173 double time_per_iter = (stop_time - start_time) / (double)SAMPLE_SIZE; 1174 double time_until_end = time_per_iter * (double)(java_objects_length - next); 1175 if ((start_time + time_until_end) >= EscapeAnalysisTimeout) { 1176 timeout = true; 1177 break; // Timeout 1178 } 1179 start_time = stop_time; 1180 time.start(); 1181 } 1182 #undef SAMPLE_SIZE 1183 1184 } 1185 if (timeout) break; 1186 if (new_edges > 0) { 1187 // Update escape states on each iteration if graph was updated. 1188 if (!find_non_escaped_objects(ptnodes_worklist, non_escaped_worklist)) { 1189 return false; // Nothing to do. 1190 } 1191 } 1192 time.stop(); 1193 if (time.seconds() >= EscapeAnalysisTimeout) { 1194 timeout = true; 1195 break; 1196 } 1197 } 1198 if ((iterations < CG_BUILD_ITER_LIMIT) && !timeout) { 1199 time.start(); 1200 // Find fields which have unknown value. 1201 int fields_length = oop_fields_worklist.length(); 1202 for (int next = 0; next < fields_length; next++) { 1203 FieldNode* field = oop_fields_worklist.at(next); 1204 if (field->edge_count() == 0) { 1205 new_edges += find_field_value(field); 1206 // This code may added new edges to phantom_object. 1207 // Need an other cycle to propagate references to phantom_object. 1208 } 1209 } 1210 time.stop(); 1211 if (time.seconds() >= EscapeAnalysisTimeout) { 1212 timeout = true; 1213 break; 1214 } 1215 } else { 1216 new_edges = 0; // Bailout 1217 } 1218 } while (new_edges > 0); 1219 1220 // Bailout if passed limits. 1221 if ((iterations >= CG_BUILD_ITER_LIMIT) || timeout) { 1222 Compile* C = _compile; 1223 if (C->log() != NULL) { 1224 C->log()->begin_elem("connectionGraph_bailout reason='reached "); 1225 C->log()->text("%s", timeout ? "time" : "iterations"); 1226 C->log()->end_elem(" limit'"); 1227 } 1228 assert(ExitEscapeAnalysisOnTimeout, "infinite EA connection graph build (%f sec, %d iterations) with %d nodes and worklist size %d", 1229 time.seconds(), iterations, nodes_size(), ptnodes_worklist.length()); 1230 // Possible infinite build_connection_graph loop, 1231 // bailout (no changes to ideal graph were made). 1232 return false; 1233 } 1234 #ifdef ASSERT 1235 if (Verbose && PrintEscapeAnalysis) { 1236 tty->print_cr("EA: %d iterations to build connection graph with %d nodes and worklist size %d", 1237 iterations, nodes_size(), ptnodes_worklist.length()); 1238 } 1239 #endif 1240 1241 #undef CG_BUILD_ITER_LIMIT 1242 1243 // Find fields initialized by NULL for non-escaping Allocations. 1244 int non_escaped_length = non_escaped_worklist.length(); 1245 for (int next = 0; next < non_escaped_length; next++) { 1246 JavaObjectNode* ptn = non_escaped_worklist.at(next); 1247 PointsToNode::EscapeState es = ptn->escape_state(); 1248 assert(es <= PointsToNode::ArgEscape, "sanity"); 1249 if (es == PointsToNode::NoEscape) { 1250 if (find_init_values(ptn, null_obj, _igvn) > 0) { 1251 // Adding references to NULL object does not change escape states 1252 // since it does not escape. Also no fields are added to NULL object. 1253 add_java_object_edges(null_obj, false); 1254 } 1255 } 1256 Node* n = ptn->ideal_node(); 1257 if (n->is_Allocate()) { 1258 // The object allocated by this Allocate node will never be 1259 // seen by an other thread. Mark it so that when it is 1260 // expanded no MemBarStoreStore is added. 1261 InitializeNode* ini = n->as_Allocate()->initialization(); 1262 if (ini != NULL) 1263 ini->set_does_not_escape(); 1264 } 1265 } 1266 return true; // Finished graph construction. 1267 } 1268 1269 // Propagate GlobalEscape and ArgEscape escape states to all nodes 1270 // and check that we still have non-escaping java objects. 1271 bool ConnectionGraph::find_non_escaped_objects(GrowableArray<PointsToNode*>& ptnodes_worklist, 1272 GrowableArray<JavaObjectNode*>& non_escaped_worklist) { 1273 GrowableArray<PointsToNode*> escape_worklist; 1274 // First, put all nodes with GlobalEscape and ArgEscape states on worklist. 1275 int ptnodes_length = ptnodes_worklist.length(); 1276 for (int next = 0; next < ptnodes_length; ++next) { 1277 PointsToNode* ptn = ptnodes_worklist.at(next); 1278 if (ptn->escape_state() >= PointsToNode::ArgEscape || 1279 ptn->fields_escape_state() >= PointsToNode::ArgEscape) { 1280 escape_worklist.push(ptn); 1281 } 1282 } 1283 // Set escape states to referenced nodes (edges list). 1284 while (escape_worklist.length() > 0) { 1285 PointsToNode* ptn = escape_worklist.pop(); 1286 PointsToNode::EscapeState es = ptn->escape_state(); 1287 PointsToNode::EscapeState field_es = ptn->fields_escape_state(); 1288 if (ptn->is_Field() && ptn->as_Field()->is_oop() && 1289 es >= PointsToNode::ArgEscape) { 1290 // GlobalEscape or ArgEscape state of field means it has unknown value. 1291 if (add_edge(ptn, phantom_obj)) { 1292 // New edge was added 1293 add_field_uses_to_worklist(ptn->as_Field()); 1294 } 1295 } 1296 for (EdgeIterator i(ptn); i.has_next(); i.next()) { 1297 PointsToNode* e = i.get(); 1298 if (e->is_Arraycopy()) { 1299 assert(ptn->arraycopy_dst(), "sanity"); 1300 // Propagate only fields escape state through arraycopy edge. 1301 if (e->fields_escape_state() < field_es) { 1302 set_fields_escape_state(e, field_es); 1303 escape_worklist.push(e); 1304 } 1305 } else if (es >= field_es) { 1306 // fields_escape_state is also set to 'es' if it is less than 'es'. 1307 if (e->escape_state() < es) { 1308 set_escape_state(e, es); 1309 escape_worklist.push(e); 1310 } 1311 } else { 1312 // Propagate field escape state. 1313 bool es_changed = false; 1314 if (e->fields_escape_state() < field_es) { 1315 set_fields_escape_state(e, field_es); 1316 es_changed = true; 1317 } 1318 if ((e->escape_state() < field_es) && 1319 e->is_Field() && ptn->is_JavaObject() && 1320 e->as_Field()->is_oop()) { 1321 // Change escape state of referenced fields. 1322 set_escape_state(e, field_es); 1323 es_changed = true; 1324 } else if (e->escape_state() < es) { 1325 set_escape_state(e, es); 1326 es_changed = true; 1327 } 1328 if (es_changed) { 1329 escape_worklist.push(e); 1330 } 1331 } 1332 } 1333 } 1334 // Remove escaped objects from non_escaped list. 1335 for (int next = non_escaped_worklist.length()-1; next >= 0 ; --next) { 1336 JavaObjectNode* ptn = non_escaped_worklist.at(next); 1337 if (ptn->escape_state() >= PointsToNode::GlobalEscape) { 1338 non_escaped_worklist.delete_at(next); 1339 } 1340 if (ptn->escape_state() == PointsToNode::NoEscape) { 1341 // Find fields in non-escaped allocations which have unknown value. 1342 find_init_values(ptn, phantom_obj, NULL); 1343 } 1344 } 1345 return (non_escaped_worklist.length() > 0); 1346 } 1347 1348 // Add all references to JavaObject node by walking over all uses. 1349 int ConnectionGraph::add_java_object_edges(JavaObjectNode* jobj, bool populate_worklist) { 1350 int new_edges = 0; 1351 if (populate_worklist) { 1352 // Populate _worklist by uses of jobj's uses. 1353 for (UseIterator i(jobj); i.has_next(); i.next()) { 1354 PointsToNode* use = i.get(); 1355 if (use->is_Arraycopy()) 1356 continue; 1357 add_uses_to_worklist(use); 1358 if (use->is_Field() && use->as_Field()->is_oop()) { 1359 // Put on worklist all field's uses (loads) and 1360 // related field nodes (same base and offset). 1361 add_field_uses_to_worklist(use->as_Field()); 1362 } 1363 } 1364 } 1365 for (int l = 0; l < _worklist.length(); l++) { 1366 PointsToNode* use = _worklist.at(l); 1367 if (PointsToNode::is_base_use(use)) { 1368 // Add reference from jobj to field and from field to jobj (field's base). 1369 use = PointsToNode::get_use_node(use)->as_Field(); 1370 if (add_base(use->as_Field(), jobj)) { 1371 new_edges++; 1372 } 1373 continue; 1374 } 1375 assert(!use->is_JavaObject(), "sanity"); 1376 if (use->is_Arraycopy()) { 1377 if (jobj == null_obj) // NULL object does not have field edges 1378 continue; 1379 // Added edge from Arraycopy node to arraycopy's source java object 1380 if (add_edge(use, jobj)) { 1381 jobj->set_arraycopy_src(); 1382 new_edges++; 1383 } 1384 // and stop here. 1385 continue; 1386 } 1387 if (!add_edge(use, jobj)) 1388 continue; // No new edge added, there was such edge already. 1389 new_edges++; 1390 if (use->is_LocalVar()) { 1391 add_uses_to_worklist(use); 1392 if (use->arraycopy_dst()) { 1393 for (EdgeIterator i(use); i.has_next(); i.next()) { 1394 PointsToNode* e = i.get(); 1395 if (e->is_Arraycopy()) { 1396 if (jobj == null_obj) // NULL object does not have field edges 1397 continue; 1398 // Add edge from arraycopy's destination java object to Arraycopy node. 1399 if (add_edge(jobj, e)) { 1400 new_edges++; 1401 jobj->set_arraycopy_dst(); 1402 } 1403 } 1404 } 1405 } 1406 } else { 1407 // Added new edge to stored in field values. 1408 // Put on worklist all field's uses (loads) and 1409 // related field nodes (same base and offset). 1410 add_field_uses_to_worklist(use->as_Field()); 1411 } 1412 } 1413 _worklist.clear(); 1414 _in_worklist.Reset(); 1415 return new_edges; 1416 } 1417 1418 // Put on worklist all related field nodes. 1419 void ConnectionGraph::add_field_uses_to_worklist(FieldNode* field) { 1420 assert(field->is_oop(), "sanity"); 1421 int offset = field->offset(); 1422 add_uses_to_worklist(field); 1423 // Loop over all bases of this field and push on worklist Field nodes 1424 // with the same offset and base (since they may reference the same field). 1425 for (BaseIterator i(field); i.has_next(); i.next()) { 1426 PointsToNode* base = i.get(); 1427 add_fields_to_worklist(field, base); 1428 // Check if the base was source object of arraycopy and go over arraycopy's 1429 // destination objects since values stored to a field of source object are 1430 // accessable by uses (loads) of fields of destination objects. 1431 if (base->arraycopy_src()) { 1432 for (UseIterator j(base); j.has_next(); j.next()) { 1433 PointsToNode* arycp = j.get(); 1434 if (arycp->is_Arraycopy()) { 1435 for (UseIterator k(arycp); k.has_next(); k.next()) { 1436 PointsToNode* abase = k.get(); 1437 if (abase->arraycopy_dst() && abase != base) { 1438 // Look for the same arraycopy reference. 1439 add_fields_to_worklist(field, abase); 1440 } 1441 } 1442 } 1443 } 1444 } 1445 } 1446 } 1447 1448 // Put on worklist all related field nodes. 1449 void ConnectionGraph::add_fields_to_worklist(FieldNode* field, PointsToNode* base) { 1450 int offset = field->offset(); 1451 if (base->is_LocalVar()) { 1452 for (UseIterator j(base); j.has_next(); j.next()) { 1453 PointsToNode* f = j.get(); 1454 if (PointsToNode::is_base_use(f)) { // Field 1455 f = PointsToNode::get_use_node(f); 1456 if (f == field || !f->as_Field()->is_oop()) 1457 continue; 1458 int offs = f->as_Field()->offset(); 1459 if (offs == offset || offset == Type::OffsetBot || offs == Type::OffsetBot) { 1460 add_to_worklist(f); 1461 } 1462 } 1463 } 1464 } else { 1465 assert(base->is_JavaObject(), "sanity"); 1466 if (// Skip phantom_object since it is only used to indicate that 1467 // this field's content globally escapes. 1468 (base != phantom_obj) && 1469 // NULL object node does not have fields. 1470 (base != null_obj)) { 1471 for (EdgeIterator i(base); i.has_next(); i.next()) { 1472 PointsToNode* f = i.get(); 1473 // Skip arraycopy edge since store to destination object field 1474 // does not update value in source object field. 1475 if (f->is_Arraycopy()) { 1476 assert(base->arraycopy_dst(), "sanity"); 1477 continue; 1478 } 1479 if (f == field || !f->as_Field()->is_oop()) 1480 continue; 1481 int offs = f->as_Field()->offset(); 1482 if (offs == offset || offset == Type::OffsetBot || offs == Type::OffsetBot) { 1483 add_to_worklist(f); 1484 } 1485 } 1486 } 1487 } 1488 } 1489 1490 // Find fields which have unknown value. 1491 int ConnectionGraph::find_field_value(FieldNode* field) { 1492 // Escaped fields should have init value already. 1493 assert(field->escape_state() == PointsToNode::NoEscape, "sanity"); 1494 int new_edges = 0; 1495 for (BaseIterator i(field); i.has_next(); i.next()) { 1496 PointsToNode* base = i.get(); 1497 if (base->is_JavaObject()) { 1498 // Skip Allocate's fields which will be processed later. 1499 if (base->ideal_node()->is_Allocate()) 1500 return 0; 1501 assert(base == null_obj, "only NULL ptr base expected here"); 1502 } 1503 } 1504 if (add_edge(field, phantom_obj)) { 1505 // New edge was added 1506 new_edges++; 1507 add_field_uses_to_worklist(field); 1508 } 1509 return new_edges; 1510 } 1511 1512 // Find fields initializing values for allocations. 1513 int ConnectionGraph::find_init_values(JavaObjectNode* pta, PointsToNode* init_val, PhaseTransform* phase) { 1514 assert(pta->escape_state() == PointsToNode::NoEscape, "Not escaped Allocate nodes only"); 1515 int new_edges = 0; 1516 Node* alloc = pta->ideal_node(); 1517 if (init_val == phantom_obj) { 1518 // Do nothing for Allocate nodes since its fields values are 1519 // "known" unless they are initialized by arraycopy/clone. 1520 if (alloc->is_Allocate() && !pta->arraycopy_dst()) 1521 return 0; 1522 assert(pta->arraycopy_dst() || alloc->as_CallStaticJava(), "sanity"); 1523 #ifdef ASSERT 1524 if (!pta->arraycopy_dst() && alloc->as_CallStaticJava()->method() == NULL) { 1525 const char* name = alloc->as_CallStaticJava()->_name; 1526 assert(strncmp(name, "_multianewarray", 15) == 0, "sanity"); 1527 } 1528 #endif 1529 // Non-escaped allocation returned from Java or runtime call have 1530 // unknown values in fields. 1531 for (EdgeIterator i(pta); i.has_next(); i.next()) { 1532 PointsToNode* field = i.get(); 1533 if (field->is_Field() && field->as_Field()->is_oop()) { 1534 if (add_edge(field, phantom_obj)) { 1535 // New edge was added 1536 new_edges++; 1537 add_field_uses_to_worklist(field->as_Field()); 1538 } 1539 } 1540 } 1541 return new_edges; 1542 } 1543 assert(init_val == null_obj, "sanity"); 1544 // Do nothing for Call nodes since its fields values are unknown. 1545 if (!alloc->is_Allocate()) 1546 return 0; 1547 1548 InitializeNode* ini = alloc->as_Allocate()->initialization(); 1549 bool visited_bottom_offset = false; 1550 GrowableArray<int> offsets_worklist; 1551 1552 // Check if an oop field's initializing value is recorded and add 1553 // a corresponding NULL if field's value if it is not recorded. 1554 // Connection Graph does not record a default initialization by NULL 1555 // captured by Initialize node. 1556 // 1557 for (EdgeIterator i(pta); i.has_next(); i.next()) { 1558 PointsToNode* field = i.get(); // Field (AddP) 1559 if (!field->is_Field() || !field->as_Field()->is_oop()) 1560 continue; // Not oop field 1561 int offset = field->as_Field()->offset(); 1562 if (offset == Type::OffsetBot) { 1563 if (!visited_bottom_offset) { 1564 // OffsetBot is used to reference array's element, 1565 // always add reference to NULL to all Field nodes since we don't 1566 // known which element is referenced. 1567 if (add_edge(field, null_obj)) { 1568 // New edge was added 1569 new_edges++; 1570 add_field_uses_to_worklist(field->as_Field()); 1571 visited_bottom_offset = true; 1572 } 1573 } 1574 } else { 1575 // Check only oop fields. 1576 const Type* adr_type = field->ideal_node()->as_AddP()->bottom_type(); 1577 if (adr_type->isa_rawptr()) { 1578 #ifdef ASSERT 1579 // Raw pointers are used for initializing stores so skip it 1580 // since it should be recorded already 1581 Node* base = get_addp_base(field->ideal_node()); 1582 assert(adr_type->isa_rawptr() && base->is_Proj() && 1583 (base->in(0) == alloc),"unexpected pointer type"); 1584 #endif 1585 continue; 1586 } 1587 if (!offsets_worklist.contains(offset)) { 1588 offsets_worklist.append(offset); 1589 Node* value = NULL; 1590 if (ini != NULL) { 1591 // StoreP::memory_type() == T_ADDRESS 1592 BasicType ft = UseCompressedOops ? T_NARROWOOP : T_ADDRESS; 1593 Node* store = ini->find_captured_store(offset, type2aelembytes(ft, true), phase); 1594 // Make sure initializing store has the same type as this AddP. 1595 // This AddP may reference non existing field because it is on a 1596 // dead branch of bimorphic call which is not eliminated yet. 1597 if (store != NULL && store->is_Store() && 1598 store->as_Store()->memory_type() == ft) { 1599 value = store->in(MemNode::ValueIn); 1600 #ifdef ASSERT 1601 if (VerifyConnectionGraph) { 1602 // Verify that AddP already points to all objects the value points to. 1603 PointsToNode* val = ptnode_adr(value->_idx); 1604 assert((val != NULL), "should be processed already"); 1605 PointsToNode* missed_obj = NULL; 1606 if (val->is_JavaObject()) { 1607 if (!field->points_to(val->as_JavaObject())) { 1608 missed_obj = val; 1609 } 1610 } else { 1611 if (!val->is_LocalVar() || (val->edge_count() == 0)) { 1612 tty->print_cr("----------init store has invalid value -----"); 1613 store->dump(); 1614 val->dump(); 1615 assert(val->is_LocalVar() && (val->edge_count() > 0), "should be processed already"); 1616 } 1617 for (EdgeIterator j(val); j.has_next(); j.next()) { 1618 PointsToNode* obj = j.get(); 1619 if (obj->is_JavaObject()) { 1620 if (!field->points_to(obj->as_JavaObject())) { 1621 missed_obj = obj; 1622 break; 1623 } 1624 } 1625 } 1626 } 1627 if (missed_obj != NULL) { 1628 tty->print_cr("----------field---------------------------------"); 1629 field->dump(); 1630 tty->print_cr("----------missed referernce to object-----------"); 1631 missed_obj->dump(); 1632 tty->print_cr("----------object referernced by init store -----"); 1633 store->dump(); 1634 val->dump(); 1635 assert(!field->points_to(missed_obj->as_JavaObject()), "missed JavaObject reference"); 1636 } 1637 } 1638 #endif 1639 } else { 1640 // There could be initializing stores which follow allocation. 1641 // For example, a volatile field store is not collected 1642 // by Initialize node. 1643 // 1644 // Need to check for dependent loads to separate such stores from 1645 // stores which follow loads. For now, add initial value NULL so 1646 // that compare pointers optimization works correctly. 1647 } 1648 } 1649 if (value == NULL) { 1650 // A field's initializing value was not recorded. Add NULL. 1651 if (add_edge(field, null_obj)) { 1652 // New edge was added 1653 new_edges++; 1654 add_field_uses_to_worklist(field->as_Field()); 1655 } 1656 } 1657 } 1658 } 1659 } 1660 return new_edges; 1661 } 1662 1663 // Adjust scalar_replaceable state after Connection Graph is built. 1664 void ConnectionGraph::adjust_scalar_replaceable_state(JavaObjectNode* jobj) { 1665 // Search for non-escaping objects which are not scalar replaceable 1666 // and mark them to propagate the state to referenced objects. 1667 1668 // 1. An object is not scalar replaceable if the field into which it is 1669 // stored has unknown offset (stored into unknown element of an array). 1670 // 1671 for (UseIterator i(jobj); i.has_next(); i.next()) { 1672 PointsToNode* use = i.get(); 1673 if (use->is_Arraycopy()) { 1674 continue; 1675 } 1676 if (use->is_Field()) { 1677 FieldNode* field = use->as_Field(); 1678 assert(field->is_oop() && field->scalar_replaceable(), "sanity"); 1679 if (field->offset() == Type::OffsetBot) { 1680 jobj->set_scalar_replaceable(false); 1681 return; 1682 } 1683 // 2. An object is not scalar replaceable if the field into which it is 1684 // stored has multiple bases one of which is null. 1685 if (field->base_count() > 1) { 1686 for (BaseIterator i(field); i.has_next(); i.next()) { 1687 PointsToNode* base = i.get(); 1688 if (base == null_obj) { 1689 jobj->set_scalar_replaceable(false); 1690 return; 1691 } 1692 } 1693 } 1694 } 1695 assert(use->is_Field() || use->is_LocalVar(), "sanity"); 1696 // 3. An object is not scalar replaceable if it is merged with other objects. 1697 for (EdgeIterator j(use); j.has_next(); j.next()) { 1698 PointsToNode* ptn = j.get(); 1699 if (ptn->is_JavaObject() && ptn != jobj) { 1700 // Mark all objects. 1701 jobj->set_scalar_replaceable(false); 1702 ptn->set_scalar_replaceable(false); 1703 } 1704 } 1705 if (!jobj->scalar_replaceable()) { 1706 return; 1707 } 1708 } 1709 1710 for (EdgeIterator j(jobj); j.has_next(); j.next()) { 1711 if (j.get()->is_Arraycopy()) { 1712 continue; 1713 } 1714 1715 // Non-escaping object node should point only to field nodes. 1716 FieldNode* field = j.get()->as_Field(); 1717 int offset = field->as_Field()->offset(); 1718 1719 // 4. An object is not scalar replaceable if it has a field with unknown 1720 // offset (array's element is accessed in loop). 1721 if (offset == Type::OffsetBot) { 1722 jobj->set_scalar_replaceable(false); 1723 return; 1724 } 1725 // 5. Currently an object is not scalar replaceable if a LoadStore node 1726 // access its field since the field value is unknown after it. 1727 // 1728 Node* n = field->ideal_node(); 1729 for (DUIterator_Fast imax, i = n->fast_outs(imax); i < imax; i++) { 1730 if (n->fast_out(i)->is_LoadStore()) { 1731 jobj->set_scalar_replaceable(false); 1732 return; 1733 } 1734 } 1735 1736 // 6. Or the address may point to more then one object. This may produce 1737 // the false positive result (set not scalar replaceable) 1738 // since the flow-insensitive escape analysis can't separate 1739 // the case when stores overwrite the field's value from the case 1740 // when stores happened on different control branches. 1741 // 1742 // Note: it will disable scalar replacement in some cases: 1743 // 1744 // Point p[] = new Point[1]; 1745 // p[0] = new Point(); // Will be not scalar replaced 1746 // 1747 // but it will save us from incorrect optimizations in next cases: 1748 // 1749 // Point p[] = new Point[1]; 1750 // if ( x ) p[0] = new Point(); // Will be not scalar replaced 1751 // 1752 if (field->base_count() > 1) { 1753 for (BaseIterator i(field); i.has_next(); i.next()) { 1754 PointsToNode* base = i.get(); 1755 // Don't take into account LocalVar nodes which 1756 // may point to only one object which should be also 1757 // this field's base by now. 1758 if (base->is_JavaObject() && base != jobj) { 1759 // Mark all bases. 1760 jobj->set_scalar_replaceable(false); 1761 base->set_scalar_replaceable(false); 1762 } 1763 } 1764 } 1765 } 1766 } 1767 1768 #ifdef ASSERT 1769 void ConnectionGraph::verify_connection_graph( 1770 GrowableArray<PointsToNode*>& ptnodes_worklist, 1771 GrowableArray<JavaObjectNode*>& non_escaped_worklist, 1772 GrowableArray<JavaObjectNode*>& java_objects_worklist, 1773 GrowableArray<Node*>& addp_worklist) { 1774 // Verify that graph is complete - no new edges could be added. 1775 int java_objects_length = java_objects_worklist.length(); 1776 int non_escaped_length = non_escaped_worklist.length(); 1777 int new_edges = 0; 1778 for (int next = 0; next < java_objects_length; ++next) { 1779 JavaObjectNode* ptn = java_objects_worklist.at(next); 1780 new_edges += add_java_object_edges(ptn, true); 1781 } 1782 assert(new_edges == 0, "graph was not complete"); 1783 // Verify that escape state is final. 1784 int length = non_escaped_worklist.length(); 1785 find_non_escaped_objects(ptnodes_worklist, non_escaped_worklist); 1786 assert((non_escaped_length == non_escaped_worklist.length()) && 1787 (non_escaped_length == length) && 1788 (_worklist.length() == 0), "escape state was not final"); 1789 1790 // Verify fields information. 1791 int addp_length = addp_worklist.length(); 1792 for (int next = 0; next < addp_length; ++next ) { 1793 Node* n = addp_worklist.at(next); 1794 FieldNode* field = ptnode_adr(n->_idx)->as_Field(); 1795 if (field->is_oop()) { 1796 // Verify that field has all bases 1797 Node* base = get_addp_base(n); 1798 PointsToNode* ptn = ptnode_adr(base->_idx); 1799 if (ptn->is_JavaObject()) { 1800 assert(field->has_base(ptn->as_JavaObject()), "sanity"); 1801 } else { 1802 assert(ptn->is_LocalVar(), "sanity"); 1803 for (EdgeIterator i(ptn); i.has_next(); i.next()) { 1804 PointsToNode* e = i.get(); 1805 if (e->is_JavaObject()) { 1806 assert(field->has_base(e->as_JavaObject()), "sanity"); 1807 } 1808 } 1809 } 1810 // Verify that all fields have initializing values. 1811 if (field->edge_count() == 0) { 1812 tty->print_cr("----------field does not have references----------"); 1813 field->dump(); 1814 for (BaseIterator i(field); i.has_next(); i.next()) { 1815 PointsToNode* base = i.get(); 1816 tty->print_cr("----------field has next base---------------------"); 1817 base->dump(); 1818 if (base->is_JavaObject() && (base != phantom_obj) && (base != null_obj)) { 1819 tty->print_cr("----------base has fields-------------------------"); 1820 for (EdgeIterator j(base); j.has_next(); j.next()) { 1821 j.get()->dump(); 1822 } 1823 tty->print_cr("----------base has references---------------------"); 1824 for (UseIterator j(base); j.has_next(); j.next()) { 1825 j.get()->dump(); 1826 } 1827 } 1828 } 1829 for (UseIterator i(field); i.has_next(); i.next()) { 1830 i.get()->dump(); 1831 } 1832 assert(field->edge_count() > 0, "sanity"); 1833 } 1834 } 1835 } 1836 } 1837 #endif 1838 1839 // Optimize ideal graph. 1840 void ConnectionGraph::optimize_ideal_graph(GrowableArray<Node*>& ptr_cmp_worklist, 1841 GrowableArray<Node*>& storestore_worklist) { 1842 Compile* C = _compile; 1843 PhaseIterGVN* igvn = _igvn; 1844 if (EliminateLocks) { 1845 // Mark locks before changing ideal graph. 1846 int cnt = C->macro_count(); 1847 for( int i=0; i < cnt; i++ ) { 1848 Node *n = C->macro_node(i); 1849 if (n->is_AbstractLock()) { // Lock and Unlock nodes 1850 AbstractLockNode* alock = n->as_AbstractLock(); 1851 if (!alock->is_non_esc_obj()) { 1852 if (not_global_escape(alock->obj_node())) { 1853 assert(!alock->is_eliminated() || alock->is_coarsened(), "sanity"); 1854 // The lock could be marked eliminated by lock coarsening 1855 // code during first IGVN before EA. Replace coarsened flag 1856 // to eliminate all associated locks/unlocks. 1857 #ifdef ASSERT 1858 alock->log_lock_optimization(C, "eliminate_lock_set_non_esc3"); 1859 #endif 1860 alock->set_non_esc_obj(); 1861 } 1862 } 1863 } 1864 } 1865 } 1866 1867 if (OptimizePtrCompare) { 1868 // Add ConI(#CC_GT) and ConI(#CC_EQ). 1869 _pcmp_neq = igvn->makecon(TypeInt::CC_GT); 1870 _pcmp_eq = igvn->makecon(TypeInt::CC_EQ); 1871 // Optimize objects compare. 1872 while (ptr_cmp_worklist.length() != 0) { 1873 Node *n = ptr_cmp_worklist.pop(); 1874 Node *res = optimize_ptr_compare(n); 1875 if (res != NULL) { 1876 #ifndef PRODUCT 1877 if (PrintOptimizePtrCompare) { 1878 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")); 1879 if (Verbose) { 1880 n->dump(1); 1881 } 1882 } 1883 #endif 1884 igvn->replace_node(n, res); 1885 } 1886 } 1887 // cleanup 1888 if (_pcmp_neq->outcnt() == 0) 1889 igvn->hash_delete(_pcmp_neq); 1890 if (_pcmp_eq->outcnt() == 0) 1891 igvn->hash_delete(_pcmp_eq); 1892 } 1893 1894 // For MemBarStoreStore nodes added in library_call.cpp, check 1895 // escape status of associated AllocateNode and optimize out 1896 // MemBarStoreStore node if the allocated object never escapes. 1897 while (storestore_worklist.length() != 0) { 1898 Node *n = storestore_worklist.pop(); 1899 MemBarStoreStoreNode *storestore = n ->as_MemBarStoreStore(); 1900 Node *alloc = storestore->in(MemBarNode::Precedent)->in(0); 1901 assert (alloc->is_Allocate(), "storestore should point to AllocateNode"); 1902 if (not_global_escape(alloc)) { 1903 MemBarNode* mb = MemBarNode::make(C, Op_MemBarCPUOrder, Compile::AliasIdxBot); 1904 mb->init_req(TypeFunc::Memory, storestore->in(TypeFunc::Memory)); 1905 mb->init_req(TypeFunc::Control, storestore->in(TypeFunc::Control)); 1906 igvn->register_new_node_with_optimizer(mb); 1907 igvn->replace_node(storestore, mb); 1908 } 1909 } 1910 } 1911 1912 // Optimize objects compare. 1913 Node* ConnectionGraph::optimize_ptr_compare(Node* n) { 1914 assert(OptimizePtrCompare, "sanity"); 1915 PointsToNode* ptn1 = ptnode_adr(n->in(1)->_idx); 1916 PointsToNode* ptn2 = ptnode_adr(n->in(2)->_idx); 1917 JavaObjectNode* jobj1 = unique_java_object(n->in(1)); 1918 JavaObjectNode* jobj2 = unique_java_object(n->in(2)); 1919 assert(ptn1->is_JavaObject() || ptn1->is_LocalVar(), "sanity"); 1920 assert(ptn2->is_JavaObject() || ptn2->is_LocalVar(), "sanity"); 1921 1922 // Check simple cases first. 1923 if (jobj1 != NULL) { 1924 if (jobj1->escape_state() == PointsToNode::NoEscape) { 1925 if (jobj1 == jobj2) { 1926 // Comparing the same not escaping object. 1927 return _pcmp_eq; 1928 } 1929 Node* obj = jobj1->ideal_node(); 1930 // Comparing not escaping allocation. 1931 if ((obj->is_Allocate() || obj->is_CallStaticJava()) && 1932 !ptn2->points_to(jobj1)) { 1933 return _pcmp_neq; // This includes nullness check. 1934 } 1935 } 1936 } 1937 if (jobj2 != NULL) { 1938 if (jobj2->escape_state() == PointsToNode::NoEscape) { 1939 Node* obj = jobj2->ideal_node(); 1940 // Comparing not escaping allocation. 1941 if ((obj->is_Allocate() || obj->is_CallStaticJava()) && 1942 !ptn1->points_to(jobj2)) { 1943 return _pcmp_neq; // This includes nullness check. 1944 } 1945 } 1946 } 1947 if (jobj1 != NULL && jobj1 != phantom_obj && 1948 jobj2 != NULL && jobj2 != phantom_obj && 1949 jobj1->ideal_node()->is_Con() && 1950 jobj2->ideal_node()->is_Con()) { 1951 // Klass or String constants compare. Need to be careful with 1952 // compressed pointers - compare types of ConN and ConP instead of nodes. 1953 const Type* t1 = jobj1->ideal_node()->get_ptr_type(); 1954 const Type* t2 = jobj2->ideal_node()->get_ptr_type(); 1955 if (t1->make_ptr() == t2->make_ptr()) { 1956 return _pcmp_eq; 1957 } else { 1958 return _pcmp_neq; 1959 } 1960 } 1961 if (ptn1->meet(ptn2)) { 1962 return NULL; // Sets are not disjoint 1963 } 1964 1965 // Sets are disjoint. 1966 bool set1_has_unknown_ptr = ptn1->points_to(phantom_obj); 1967 bool set2_has_unknown_ptr = ptn2->points_to(phantom_obj); 1968 bool set1_has_null_ptr = ptn1->points_to(null_obj); 1969 bool set2_has_null_ptr = ptn2->points_to(null_obj); 1970 if ((set1_has_unknown_ptr && set2_has_null_ptr) || 1971 (set2_has_unknown_ptr && set1_has_null_ptr)) { 1972 // Check nullness of unknown object. 1973 return NULL; 1974 } 1975 1976 // Disjointness by itself is not sufficient since 1977 // alias analysis is not complete for escaped objects. 1978 // Disjoint sets are definitely unrelated only when 1979 // at least one set has only not escaping allocations. 1980 if (!set1_has_unknown_ptr && !set1_has_null_ptr) { 1981 if (ptn1->non_escaping_allocation()) { 1982 return _pcmp_neq; 1983 } 1984 } 1985 if (!set2_has_unknown_ptr && !set2_has_null_ptr) { 1986 if (ptn2->non_escaping_allocation()) { 1987 return _pcmp_neq; 1988 } 1989 } 1990 return NULL; 1991 } 1992 1993 // Connection Graph constuction functions. 1994 1995 void ConnectionGraph::add_local_var(Node *n, PointsToNode::EscapeState es) { 1996 PointsToNode* ptadr = _nodes.at(n->_idx); 1997 if (ptadr != NULL) { 1998 assert(ptadr->is_LocalVar() && ptadr->ideal_node() == n, "sanity"); 1999 return; 2000 } 2001 Compile* C = _compile; 2002 ptadr = new (C->comp_arena()) LocalVarNode(this, n, es); 2003 _nodes.at_put(n->_idx, ptadr); 2004 } 2005 2006 void ConnectionGraph::add_java_object(Node *n, PointsToNode::EscapeState es) { 2007 PointsToNode* ptadr = _nodes.at(n->_idx); 2008 if (ptadr != NULL) { 2009 assert(ptadr->is_JavaObject() && ptadr->ideal_node() == n, "sanity"); 2010 return; 2011 } 2012 Compile* C = _compile; 2013 ptadr = new (C->comp_arena()) JavaObjectNode(this, n, es); 2014 _nodes.at_put(n->_idx, ptadr); 2015 } 2016 2017 void ConnectionGraph::add_field(Node *n, PointsToNode::EscapeState es, int offset) { 2018 PointsToNode* ptadr = _nodes.at(n->_idx); 2019 if (ptadr != NULL) { 2020 assert(ptadr->is_Field() && ptadr->ideal_node() == n, "sanity"); 2021 return; 2022 } 2023 bool unsafe = false; 2024 bool is_oop = is_oop_field(n, offset, &unsafe); 2025 if (unsafe) { 2026 es = PointsToNode::GlobalEscape; 2027 } 2028 Compile* C = _compile; 2029 FieldNode* field = new (C->comp_arena()) FieldNode(this, n, es, offset, is_oop); 2030 _nodes.at_put(n->_idx, field); 2031 } 2032 2033 void ConnectionGraph::add_arraycopy(Node *n, PointsToNode::EscapeState es, 2034 PointsToNode* src, PointsToNode* dst) { 2035 assert(!src->is_Field() && !dst->is_Field(), "only for JavaObject and LocalVar"); 2036 assert((src != null_obj) && (dst != null_obj), "not for ConP NULL"); 2037 PointsToNode* ptadr = _nodes.at(n->_idx); 2038 if (ptadr != NULL) { 2039 assert(ptadr->is_Arraycopy() && ptadr->ideal_node() == n, "sanity"); 2040 return; 2041 } 2042 Compile* C = _compile; 2043 ptadr = new (C->comp_arena()) ArraycopyNode(this, n, es); 2044 _nodes.at_put(n->_idx, ptadr); 2045 // Add edge from arraycopy node to source object. 2046 (void)add_edge(ptadr, src); 2047 src->set_arraycopy_src(); 2048 // Add edge from destination object to arraycopy node. 2049 (void)add_edge(dst, ptadr); 2050 dst->set_arraycopy_dst(); 2051 } 2052 2053 bool ConnectionGraph::is_oop_field(Node* n, int offset, bool* unsafe) { 2054 const Type* adr_type = n->as_AddP()->bottom_type(); 2055 BasicType bt = T_INT; 2056 if (offset == Type::OffsetBot) { 2057 // Check only oop fields. 2058 if (!adr_type->isa_aryptr() || 2059 (adr_type->isa_aryptr()->klass() == NULL) || 2060 adr_type->isa_aryptr()->klass()->is_obj_array_klass()) { 2061 // OffsetBot is used to reference array's element. Ignore first AddP. 2062 if (find_second_addp(n, n->in(AddPNode::Base)) == NULL) { 2063 bt = T_OBJECT; 2064 } 2065 } 2066 } else if (offset != oopDesc::klass_offset_in_bytes()) { 2067 if (adr_type->isa_instptr()) { 2068 ciField* field = _compile->alias_type(adr_type->isa_instptr())->field(); 2069 if (field != NULL) { 2070 bt = field->layout_type(); 2071 } else { 2072 // Check for unsafe oop field access 2073 if (n->has_out_with(Op_StoreP, Op_LoadP, Op_StoreN, Op_LoadN) || 2074 n->has_out_with(Op_GetAndSetP, Op_GetAndSetN, Op_CompareAndExchangeP, Op_CompareAndExchangeN) || 2075 n->has_out_with(Op_CompareAndSwapP, Op_CompareAndSwapN, Op_WeakCompareAndSwapP, Op_WeakCompareAndSwapN)) { 2076 bt = T_OBJECT; 2077 (*unsafe) = true; 2078 } 2079 } 2080 } else if (adr_type->isa_aryptr()) { 2081 if (offset == arrayOopDesc::length_offset_in_bytes()) { 2082 // Ignore array length load. 2083 } else if (find_second_addp(n, n->in(AddPNode::Base)) != NULL) { 2084 // Ignore first AddP. 2085 } else { 2086 const Type* elemtype = adr_type->isa_aryptr()->elem(); 2087 bt = elemtype->array_element_basic_type(); 2088 } 2089 } else if (adr_type->isa_rawptr() || adr_type->isa_klassptr()) { 2090 // Allocation initialization, ThreadLocal field access, unsafe access 2091 if (n->has_out_with(Op_StoreP, Op_LoadP, Op_StoreN, Op_LoadN) || 2092 n->has_out_with(Op_GetAndSetP, Op_GetAndSetN, Op_CompareAndExchangeP, Op_CompareAndExchangeN) || 2093 n->has_out_with(Op_CompareAndSwapP, Op_CompareAndSwapN, Op_WeakCompareAndSwapP, Op_WeakCompareAndSwapN)) { 2094 bt = T_OBJECT; 2095 } 2096 } 2097 } 2098 return (bt == T_OBJECT || bt == T_NARROWOOP || bt == T_ARRAY); 2099 } 2100 2101 // Returns unique pointed java object or NULL. 2102 JavaObjectNode* ConnectionGraph::unique_java_object(Node *n) { 2103 assert(!_collecting, "should not call when contructed graph"); 2104 // If the node was created after the escape computation we can't answer. 2105 uint idx = n->_idx; 2106 if (idx >= nodes_size()) { 2107 return NULL; 2108 } 2109 PointsToNode* ptn = ptnode_adr(idx); 2110 if (ptn->is_JavaObject()) { 2111 return ptn->as_JavaObject(); 2112 } 2113 assert(ptn->is_LocalVar(), "sanity"); 2114 // Check all java objects it points to. 2115 JavaObjectNode* jobj = NULL; 2116 for (EdgeIterator i(ptn); i.has_next(); i.next()) { 2117 PointsToNode* e = i.get(); 2118 if (e->is_JavaObject()) { 2119 if (jobj == NULL) { 2120 jobj = e->as_JavaObject(); 2121 } else if (jobj != e) { 2122 return NULL; 2123 } 2124 } 2125 } 2126 return jobj; 2127 } 2128 2129 // Return true if this node points only to non-escaping allocations. 2130 bool PointsToNode::non_escaping_allocation() { 2131 if (is_JavaObject()) { 2132 Node* n = ideal_node(); 2133 if (n->is_Allocate() || n->is_CallStaticJava()) { 2134 return (escape_state() == PointsToNode::NoEscape); 2135 } else { 2136 return false; 2137 } 2138 } 2139 assert(is_LocalVar(), "sanity"); 2140 // Check all java objects it points to. 2141 for (EdgeIterator i(this); i.has_next(); i.next()) { 2142 PointsToNode* e = i.get(); 2143 if (e->is_JavaObject()) { 2144 Node* n = e->ideal_node(); 2145 if ((e->escape_state() != PointsToNode::NoEscape) || 2146 !(n->is_Allocate() || n->is_CallStaticJava())) { 2147 return false; 2148 } 2149 } 2150 } 2151 return true; 2152 } 2153 2154 // Return true if we know the node does not escape globally. 2155 bool ConnectionGraph::not_global_escape(Node *n) { 2156 assert(!_collecting, "should not call during graph construction"); 2157 // If the node was created after the escape computation we can't answer. 2158 uint idx = n->_idx; 2159 if (idx >= nodes_size()) { 2160 return false; 2161 } 2162 PointsToNode* ptn = ptnode_adr(idx); 2163 PointsToNode::EscapeState es = ptn->escape_state(); 2164 // If we have already computed a value, return it. 2165 if (es >= PointsToNode::GlobalEscape) 2166 return false; 2167 if (ptn->is_JavaObject()) { 2168 return true; // (es < PointsToNode::GlobalEscape); 2169 } 2170 assert(ptn->is_LocalVar(), "sanity"); 2171 // Check all java objects it points to. 2172 for (EdgeIterator i(ptn); i.has_next(); i.next()) { 2173 if (i.get()->escape_state() >= PointsToNode::GlobalEscape) 2174 return false; 2175 } 2176 return true; 2177 } 2178 2179 2180 // Helper functions 2181 2182 // Return true if this node points to specified node or nodes it points to. 2183 bool PointsToNode::points_to(JavaObjectNode* ptn) const { 2184 if (is_JavaObject()) { 2185 return (this == ptn); 2186 } 2187 assert(is_LocalVar() || is_Field(), "sanity"); 2188 for (EdgeIterator i(this); i.has_next(); i.next()) { 2189 if (i.get() == ptn) 2190 return true; 2191 } 2192 return false; 2193 } 2194 2195 // Return true if one node points to an other. 2196 bool PointsToNode::meet(PointsToNode* ptn) { 2197 if (this == ptn) { 2198 return true; 2199 } else if (ptn->is_JavaObject()) { 2200 return this->points_to(ptn->as_JavaObject()); 2201 } else if (this->is_JavaObject()) { 2202 return ptn->points_to(this->as_JavaObject()); 2203 } 2204 assert(this->is_LocalVar() && ptn->is_LocalVar(), "sanity"); 2205 int ptn_count = ptn->edge_count(); 2206 for (EdgeIterator i(this); i.has_next(); i.next()) { 2207 PointsToNode* this_e = i.get(); 2208 for (int j = 0; j < ptn_count; j++) { 2209 if (this_e == ptn->edge(j)) 2210 return true; 2211 } 2212 } 2213 return false; 2214 } 2215 2216 #ifdef ASSERT 2217 // Return true if bases point to this java object. 2218 bool FieldNode::has_base(JavaObjectNode* jobj) const { 2219 for (BaseIterator i(this); i.has_next(); i.next()) { 2220 if (i.get() == jobj) 2221 return true; 2222 } 2223 return false; 2224 } 2225 #endif 2226 2227 int ConnectionGraph::address_offset(Node* adr, PhaseTransform *phase) { 2228 const Type *adr_type = phase->type(adr); 2229 if (adr->is_AddP() && adr_type->isa_oopptr() == NULL && 2230 adr->in(AddPNode::Address)->is_Proj() && 2231 adr->in(AddPNode::Address)->in(0)->is_Allocate()) { 2232 // We are computing a raw address for a store captured by an Initialize 2233 // compute an appropriate address type. AddP cases #3 and #5 (see below). 2234 int offs = (int)phase->find_intptr_t_con(adr->in(AddPNode::Offset), Type::OffsetBot); 2235 assert(offs != Type::OffsetBot || 2236 adr->in(AddPNode::Address)->in(0)->is_AllocateArray(), 2237 "offset must be a constant or it is initialization of array"); 2238 return offs; 2239 } 2240 const TypePtr *t_ptr = adr_type->isa_ptr(); 2241 assert(t_ptr != NULL, "must be a pointer type"); 2242 return t_ptr->offset(); 2243 } 2244 2245 Node* ConnectionGraph::get_addp_base(Node *addp) { 2246 assert(addp->is_AddP(), "must be AddP"); 2247 // 2248 // AddP cases for Base and Address inputs: 2249 // case #1. Direct object's field reference: 2250 // Allocate 2251 // | 2252 // Proj #5 ( oop result ) 2253 // | 2254 // CheckCastPP (cast to instance type) 2255 // | | 2256 // AddP ( base == address ) 2257 // 2258 // case #2. Indirect object's field reference: 2259 // Phi 2260 // | 2261 // CastPP (cast to instance type) 2262 // | | 2263 // AddP ( base == address ) 2264 // 2265 // case #3. Raw object's field reference for Initialize node: 2266 // Allocate 2267 // | 2268 // Proj #5 ( oop result ) 2269 // top | 2270 // \ | 2271 // AddP ( base == top ) 2272 // 2273 // case #4. Array's element reference: 2274 // {CheckCastPP | CastPP} 2275 // | | | 2276 // | AddP ( array's element offset ) 2277 // | | 2278 // AddP ( array's offset ) 2279 // 2280 // case #5. Raw object's field reference for arraycopy stub call: 2281 // The inline_native_clone() case when the arraycopy stub is called 2282 // after the allocation before Initialize and CheckCastPP nodes. 2283 // Allocate 2284 // | 2285 // Proj #5 ( oop result ) 2286 // | | 2287 // AddP ( base == address ) 2288 // 2289 // case #6. Constant Pool, ThreadLocal, CastX2P or 2290 // Raw object's field reference: 2291 // {ConP, ThreadLocal, CastX2P, raw Load} 2292 // top | 2293 // \ | 2294 // AddP ( base == top ) 2295 // 2296 // case #7. Klass's field reference. 2297 // LoadKlass 2298 // | | 2299 // AddP ( base == address ) 2300 // 2301 // case #8. narrow Klass's field reference. 2302 // LoadNKlass 2303 // | 2304 // DecodeN 2305 // | | 2306 // AddP ( base == address ) 2307 // 2308 // case #9. Mixed unsafe access 2309 // {instance} 2310 // | 2311 // CheckCastPP (raw) 2312 // top | 2313 // \ | 2314 // AddP ( base == top ) 2315 // 2316 Node *base = addp->in(AddPNode::Base); 2317 if (base->uncast()->is_top()) { // The AddP case #3 and #6 and #9. 2318 base = addp->in(AddPNode::Address); 2319 while (base->is_AddP()) { 2320 // Case #6 (unsafe access) may have several chained AddP nodes. 2321 assert(base->in(AddPNode::Base)->uncast()->is_top(), "expected unsafe access address only"); 2322 base = base->in(AddPNode::Address); 2323 } 2324 if (base->Opcode() == Op_CheckCastPP && 2325 base->bottom_type()->isa_rawptr() && 2326 _igvn->type(base->in(1))->isa_oopptr()) { 2327 base = base->in(1); // Case #9 2328 } else { 2329 Node* uncast_base = base->uncast(); 2330 int opcode = uncast_base->Opcode(); 2331 assert(opcode == Op_ConP || opcode == Op_ThreadLocal || 2332 opcode == Op_CastX2P || uncast_base->is_DecodeNarrowPtr() || 2333 (uncast_base->is_Mem() && (uncast_base->bottom_type()->isa_rawptr() != NULL)) || 2334 (uncast_base->is_Proj() && uncast_base->in(0)->is_Allocate()), "sanity"); 2335 } 2336 } 2337 return base; 2338 } 2339 2340 Node* ConnectionGraph::find_second_addp(Node* addp, Node* n) { 2341 assert(addp->is_AddP() && addp->outcnt() > 0, "Don't process dead nodes"); 2342 Node* addp2 = addp->raw_out(0); 2343 if (addp->outcnt() == 1 && addp2->is_AddP() && 2344 addp2->in(AddPNode::Base) == n && 2345 addp2->in(AddPNode::Address) == addp) { 2346 assert(addp->in(AddPNode::Base) == n, "expecting the same base"); 2347 // 2348 // Find array's offset to push it on worklist first and 2349 // as result process an array's element offset first (pushed second) 2350 // to avoid CastPP for the array's offset. 2351 // Otherwise the inserted CastPP (LocalVar) will point to what 2352 // the AddP (Field) points to. Which would be wrong since 2353 // the algorithm expects the CastPP has the same point as 2354 // as AddP's base CheckCastPP (LocalVar). 2355 // 2356 // ArrayAllocation 2357 // | 2358 // CheckCastPP 2359 // | 2360 // memProj (from ArrayAllocation CheckCastPP) 2361 // | || 2362 // | || Int (element index) 2363 // | || | ConI (log(element size)) 2364 // | || | / 2365 // | || LShift 2366 // | || / 2367 // | AddP (array's element offset) 2368 // | | 2369 // | | ConI (array's offset: #12(32-bits) or #24(64-bits)) 2370 // | / / 2371 // AddP (array's offset) 2372 // | 2373 // Load/Store (memory operation on array's element) 2374 // 2375 return addp2; 2376 } 2377 return NULL; 2378 } 2379 2380 // 2381 // Adjust the type and inputs of an AddP which computes the 2382 // address of a field of an instance 2383 // 2384 bool ConnectionGraph::split_AddP(Node *addp, Node *base) { 2385 PhaseGVN* igvn = _igvn; 2386 const TypeOopPtr *base_t = igvn->type(base)->isa_oopptr(); 2387 assert(base_t != NULL && base_t->is_known_instance(), "expecting instance oopptr"); 2388 const TypeOopPtr *t = igvn->type(addp)->isa_oopptr(); 2389 if (t == NULL) { 2390 // We are computing a raw address for a store captured by an Initialize 2391 // compute an appropriate address type (cases #3 and #5). 2392 assert(igvn->type(addp) == TypeRawPtr::NOTNULL, "must be raw pointer"); 2393 assert(addp->in(AddPNode::Address)->is_Proj(), "base of raw address must be result projection from allocation"); 2394 intptr_t offs = (int)igvn->find_intptr_t_con(addp->in(AddPNode::Offset), Type::OffsetBot); 2395 assert(offs != Type::OffsetBot, "offset must be a constant"); 2396 t = base_t->add_offset(offs)->is_oopptr(); 2397 } 2398 int inst_id = base_t->instance_id(); 2399 assert(!t->is_known_instance() || t->instance_id() == inst_id, 2400 "old type must be non-instance or match new type"); 2401 2402 // The type 't' could be subclass of 'base_t'. 2403 // As result t->offset() could be large then base_t's size and it will 2404 // cause the failure in add_offset() with narrow oops since TypeOopPtr() 2405 // constructor verifies correctness of the offset. 2406 // 2407 // It could happened on subclass's branch (from the type profiling 2408 // inlining) which was not eliminated during parsing since the exactness 2409 // of the allocation type was not propagated to the subclass type check. 2410 // 2411 // Or the type 't' could be not related to 'base_t' at all. 2412 // It could happened when CHA type is different from MDO type on a dead path 2413 // (for example, from instanceof check) which is not collapsed during parsing. 2414 // 2415 // Do nothing for such AddP node and don't process its users since 2416 // this code branch will go away. 2417 // 2418 if (!t->is_known_instance() && 2419 !base_t->klass()->is_subtype_of(t->klass())) { 2420 return false; // bail out 2421 } 2422 const TypeOopPtr *tinst = base_t->add_offset(t->offset())->is_oopptr(); 2423 // Do NOT remove the next line: ensure a new alias index is allocated 2424 // for the instance type. Note: C++ will not remove it since the call 2425 // has side effect. 2426 int alias_idx = _compile->get_alias_index(tinst); 2427 igvn->set_type(addp, tinst); 2428 // record the allocation in the node map 2429 set_map(addp, get_map(base->_idx)); 2430 // Set addp's Base and Address to 'base'. 2431 Node *abase = addp->in(AddPNode::Base); 2432 Node *adr = addp->in(AddPNode::Address); 2433 if (adr->is_Proj() && adr->in(0)->is_Allocate() && 2434 adr->in(0)->_idx == (uint)inst_id) { 2435 // Skip AddP cases #3 and #5. 2436 } else { 2437 assert(!abase->is_top(), "sanity"); // AddP case #3 2438 if (abase != base) { 2439 igvn->hash_delete(addp); 2440 addp->set_req(AddPNode::Base, base); 2441 if (abase == adr) { 2442 addp->set_req(AddPNode::Address, base); 2443 } else { 2444 // AddP case #4 (adr is array's element offset AddP node) 2445 #ifdef ASSERT 2446 const TypeOopPtr *atype = igvn->type(adr)->isa_oopptr(); 2447 assert(adr->is_AddP() && atype != NULL && 2448 atype->instance_id() == inst_id, "array's element offset should be processed first"); 2449 #endif 2450 } 2451 igvn->hash_insert(addp); 2452 } 2453 } 2454 // Put on IGVN worklist since at least addp's type was changed above. 2455 record_for_optimizer(addp); 2456 return true; 2457 } 2458 2459 // 2460 // Create a new version of orig_phi if necessary. Returns either the newly 2461 // created phi or an existing phi. Sets create_new to indicate whether a new 2462 // phi was created. Cache the last newly created phi in the node map. 2463 // 2464 PhiNode *ConnectionGraph::create_split_phi(PhiNode *orig_phi, int alias_idx, GrowableArray<PhiNode *> &orig_phi_worklist, bool &new_created) { 2465 Compile *C = _compile; 2466 PhaseGVN* igvn = _igvn; 2467 new_created = false; 2468 int phi_alias_idx = C->get_alias_index(orig_phi->adr_type()); 2469 // nothing to do if orig_phi is bottom memory or matches alias_idx 2470 if (phi_alias_idx == alias_idx) { 2471 return orig_phi; 2472 } 2473 // Have we recently created a Phi for this alias index? 2474 PhiNode *result = get_map_phi(orig_phi->_idx); 2475 if (result != NULL && C->get_alias_index(result->adr_type()) == alias_idx) { 2476 return result; 2477 } 2478 // Previous check may fail when the same wide memory Phi was split into Phis 2479 // for different memory slices. Search all Phis for this region. 2480 if (result != NULL) { 2481 Node* region = orig_phi->in(0); 2482 for (DUIterator_Fast imax, i = region->fast_outs(imax); i < imax; i++) { 2483 Node* phi = region->fast_out(i); 2484 if (phi->is_Phi() && 2485 C->get_alias_index(phi->as_Phi()->adr_type()) == alias_idx) { 2486 assert(phi->_idx >= nodes_size(), "only new Phi per instance memory slice"); 2487 return phi->as_Phi(); 2488 } 2489 } 2490 } 2491 if (C->live_nodes() + 2*NodeLimitFudgeFactor > C->max_node_limit()) { 2492 if (C->do_escape_analysis() == true && !C->failing()) { 2493 // Retry compilation without escape analysis. 2494 // If this is the first failure, the sentinel string will "stick" 2495 // to the Compile object, and the C2Compiler will see it and retry. 2496 C->record_failure(C2Compiler::retry_no_escape_analysis()); 2497 } 2498 return NULL; 2499 } 2500 orig_phi_worklist.append_if_missing(orig_phi); 2501 const TypePtr *atype = C->get_adr_type(alias_idx); 2502 result = PhiNode::make(orig_phi->in(0), NULL, Type::MEMORY, atype); 2503 C->copy_node_notes_to(result, orig_phi); 2504 igvn->set_type(result, result->bottom_type()); 2505 record_for_optimizer(result); 2506 set_map(orig_phi, result); 2507 new_created = true; 2508 return result; 2509 } 2510 2511 // 2512 // Return a new version of Memory Phi "orig_phi" with the inputs having the 2513 // specified alias index. 2514 // 2515 PhiNode *ConnectionGraph::split_memory_phi(PhiNode *orig_phi, int alias_idx, GrowableArray<PhiNode *> &orig_phi_worklist) { 2516 assert(alias_idx != Compile::AliasIdxBot, "can't split out bottom memory"); 2517 Compile *C = _compile; 2518 PhaseGVN* igvn = _igvn; 2519 bool new_phi_created; 2520 PhiNode *result = create_split_phi(orig_phi, alias_idx, orig_phi_worklist, new_phi_created); 2521 if (!new_phi_created) { 2522 return result; 2523 } 2524 GrowableArray<PhiNode *> phi_list; 2525 GrowableArray<uint> cur_input; 2526 PhiNode *phi = orig_phi; 2527 uint idx = 1; 2528 bool finished = false; 2529 while(!finished) { 2530 while (idx < phi->req()) { 2531 Node *mem = find_inst_mem(phi->in(idx), alias_idx, orig_phi_worklist); 2532 if (mem != NULL && mem->is_Phi()) { 2533 PhiNode *newphi = create_split_phi(mem->as_Phi(), alias_idx, orig_phi_worklist, new_phi_created); 2534 if (new_phi_created) { 2535 // found an phi for which we created a new split, push current one on worklist and begin 2536 // processing new one 2537 phi_list.push(phi); 2538 cur_input.push(idx); 2539 phi = mem->as_Phi(); 2540 result = newphi; 2541 idx = 1; 2542 continue; 2543 } else { 2544 mem = newphi; 2545 } 2546 } 2547 if (C->failing()) { 2548 return NULL; 2549 } 2550 result->set_req(idx++, mem); 2551 } 2552 #ifdef ASSERT 2553 // verify that the new Phi has an input for each input of the original 2554 assert( phi->req() == result->req(), "must have same number of inputs."); 2555 assert( result->in(0) != NULL && result->in(0) == phi->in(0), "regions must match"); 2556 #endif 2557 // Check if all new phi's inputs have specified alias index. 2558 // Otherwise use old phi. 2559 for (uint i = 1; i < phi->req(); i++) { 2560 Node* in = result->in(i); 2561 assert((phi->in(i) == NULL) == (in == NULL), "inputs must correspond."); 2562 } 2563 // we have finished processing a Phi, see if there are any more to do 2564 finished = (phi_list.length() == 0 ); 2565 if (!finished) { 2566 phi = phi_list.pop(); 2567 idx = cur_input.pop(); 2568 PhiNode *prev_result = get_map_phi(phi->_idx); 2569 prev_result->set_req(idx++, result); 2570 result = prev_result; 2571 } 2572 } 2573 return result; 2574 } 2575 2576 // 2577 // The next methods are derived from methods in MemNode. 2578 // 2579 Node* ConnectionGraph::step_through_mergemem(MergeMemNode *mmem, int alias_idx, const TypeOopPtr *toop) { 2580 Node *mem = mmem; 2581 // TypeOopPtr::NOTNULL+any is an OOP with unknown offset - generally 2582 // means an array I have not precisely typed yet. Do not do any 2583 // alias stuff with it any time soon. 2584 if (toop->base() != Type::AnyPtr && 2585 !(toop->klass() != NULL && 2586 toop->klass()->is_java_lang_Object() && 2587 toop->offset() == Type::OffsetBot)) { 2588 mem = mmem->memory_at(alias_idx); 2589 // Update input if it is progress over what we have now 2590 } 2591 return mem; 2592 } 2593 2594 // 2595 // Move memory users to their memory slices. 2596 // 2597 void ConnectionGraph::move_inst_mem(Node* n, GrowableArray<PhiNode *> &orig_phis) { 2598 Compile* C = _compile; 2599 PhaseGVN* igvn = _igvn; 2600 const TypePtr* tp = igvn->type(n->in(MemNode::Address))->isa_ptr(); 2601 assert(tp != NULL, "ptr type"); 2602 int alias_idx = C->get_alias_index(tp); 2603 int general_idx = C->get_general_index(alias_idx); 2604 2605 // Move users first 2606 for (DUIterator_Fast imax, i = n->fast_outs(imax); i < imax; i++) { 2607 Node* use = n->fast_out(i); 2608 if (use->is_MergeMem()) { 2609 MergeMemNode* mmem = use->as_MergeMem(); 2610 assert(n == mmem->memory_at(alias_idx), "should be on instance memory slice"); 2611 if (n != mmem->memory_at(general_idx) || alias_idx == general_idx) { 2612 continue; // Nothing to do 2613 } 2614 // Replace previous general reference to mem node. 2615 uint orig_uniq = C->unique(); 2616 Node* m = find_inst_mem(n, general_idx, orig_phis); 2617 assert(orig_uniq == C->unique(), "no new nodes"); 2618 mmem->set_memory_at(general_idx, m); 2619 --imax; 2620 --i; 2621 } else if (use->is_MemBar()) { 2622 assert(!use->is_Initialize(), "initializing stores should not be moved"); 2623 if (use->req() > MemBarNode::Precedent && 2624 use->in(MemBarNode::Precedent) == n) { 2625 // Don't move related membars. 2626 record_for_optimizer(use); 2627 continue; 2628 } 2629 tp = use->as_MemBar()->adr_type()->isa_ptr(); 2630 if ((tp != NULL && C->get_alias_index(tp) == alias_idx) || 2631 alias_idx == general_idx) { 2632 continue; // Nothing to do 2633 } 2634 // Move to general memory slice. 2635 uint orig_uniq = C->unique(); 2636 Node* m = find_inst_mem(n, general_idx, orig_phis); 2637 assert(orig_uniq == C->unique(), "no new nodes"); 2638 igvn->hash_delete(use); 2639 imax -= use->replace_edge(n, m); 2640 igvn->hash_insert(use); 2641 record_for_optimizer(use); 2642 --i; 2643 #ifdef ASSERT 2644 } else if (use->is_Mem()) { 2645 if (use->Opcode() == Op_StoreCM && use->in(MemNode::OopStore) == n) { 2646 // Don't move related cardmark. 2647 continue; 2648 } 2649 // Memory nodes should have new memory input. 2650 tp = igvn->type(use->in(MemNode::Address))->isa_ptr(); 2651 assert(tp != NULL, "ptr type"); 2652 int idx = C->get_alias_index(tp); 2653 assert(get_map(use->_idx) != NULL || idx == alias_idx, 2654 "Following memory nodes should have new memory input or be on the same memory slice"); 2655 } else if (use->is_Phi()) { 2656 // Phi nodes should be split and moved already. 2657 tp = use->as_Phi()->adr_type()->isa_ptr(); 2658 assert(tp != NULL, "ptr type"); 2659 int idx = C->get_alias_index(tp); 2660 assert(idx == alias_idx, "Following Phi nodes should be on the same memory slice"); 2661 } else { 2662 use->dump(); 2663 assert(false, "should not be here"); 2664 #endif 2665 } 2666 } 2667 } 2668 2669 // 2670 // Search memory chain of "mem" to find a MemNode whose address 2671 // is the specified alias index. 2672 // 2673 Node* ConnectionGraph::find_inst_mem(Node *orig_mem, int alias_idx, GrowableArray<PhiNode *> &orig_phis) { 2674 if (orig_mem == NULL) 2675 return orig_mem; 2676 Compile* C = _compile; 2677 PhaseGVN* igvn = _igvn; 2678 const TypeOopPtr *toop = C->get_adr_type(alias_idx)->isa_oopptr(); 2679 bool is_instance = (toop != NULL) && toop->is_known_instance(); 2680 Node *start_mem = C->start()->proj_out_or_null(TypeFunc::Memory); 2681 Node *prev = NULL; 2682 Node *result = orig_mem; 2683 while (prev != result) { 2684 prev = result; 2685 if (result == start_mem) 2686 break; // hit one of our sentinels 2687 if (result->is_Mem()) { 2688 const Type *at = igvn->type(result->in(MemNode::Address)); 2689 if (at == Type::TOP) 2690 break; // Dead 2691 assert (at->isa_ptr() != NULL, "pointer type required."); 2692 int idx = C->get_alias_index(at->is_ptr()); 2693 if (idx == alias_idx) 2694 break; // Found 2695 if (!is_instance && (at->isa_oopptr() == NULL || 2696 !at->is_oopptr()->is_known_instance())) { 2697 break; // Do not skip store to general memory slice. 2698 } 2699 result = result->in(MemNode::Memory); 2700 } 2701 if (!is_instance) 2702 continue; // don't search further for non-instance types 2703 // skip over a call which does not affect this memory slice 2704 if (result->is_Proj() && result->as_Proj()->_con == TypeFunc::Memory) { 2705 Node *proj_in = result->in(0); 2706 if (proj_in->is_Allocate() && proj_in->_idx == (uint)toop->instance_id()) { 2707 break; // hit one of our sentinels 2708 } else if (proj_in->is_Call()) { 2709 // ArrayCopy node processed here as well 2710 CallNode *call = proj_in->as_Call(); 2711 if (!call->may_modify(toop, igvn)) { 2712 result = call->in(TypeFunc::Memory); 2713 } 2714 } else if (proj_in->is_Initialize()) { 2715 AllocateNode* alloc = proj_in->as_Initialize()->allocation(); 2716 // Stop if this is the initialization for the object instance which 2717 // which contains this memory slice, otherwise skip over it. 2718 if (alloc == NULL || alloc->_idx != (uint)toop->instance_id()) { 2719 result = proj_in->in(TypeFunc::Memory); 2720 } 2721 } else if (proj_in->is_MemBar()) { 2722 if (proj_in->in(TypeFunc::Memory)->is_MergeMem() && 2723 proj_in->in(TypeFunc::Memory)->as_MergeMem()->in(Compile::AliasIdxRaw)->is_Proj() && 2724 proj_in->in(TypeFunc::Memory)->as_MergeMem()->in(Compile::AliasIdxRaw)->in(0)->is_ArrayCopy()) { 2725 // clone 2726 ArrayCopyNode* ac = proj_in->in(TypeFunc::Memory)->as_MergeMem()->in(Compile::AliasIdxRaw)->in(0)->as_ArrayCopy(); 2727 if (ac->may_modify(toop, igvn)) { 2728 break; 2729 } 2730 } 2731 result = proj_in->in(TypeFunc::Memory); 2732 } 2733 } else if (result->is_MergeMem()) { 2734 MergeMemNode *mmem = result->as_MergeMem(); 2735 result = step_through_mergemem(mmem, alias_idx, toop); 2736 if (result == mmem->base_memory()) { 2737 // Didn't find instance memory, search through general slice recursively. 2738 result = mmem->memory_at(C->get_general_index(alias_idx)); 2739 result = find_inst_mem(result, alias_idx, orig_phis); 2740 if (C->failing()) { 2741 return NULL; 2742 } 2743 mmem->set_memory_at(alias_idx, result); 2744 } 2745 } else if (result->is_Phi() && 2746 C->get_alias_index(result->as_Phi()->adr_type()) != alias_idx) { 2747 Node *un = result->as_Phi()->unique_input(igvn); 2748 if (un != NULL) { 2749 orig_phis.append_if_missing(result->as_Phi()); 2750 result = un; 2751 } else { 2752 break; 2753 } 2754 } else if (result->is_ClearArray()) { 2755 if (!ClearArrayNode::step_through(&result, (uint)toop->instance_id(), igvn)) { 2756 // Can not bypass initialization of the instance 2757 // we are looking for. 2758 break; 2759 } 2760 // Otherwise skip it (the call updated 'result' value). 2761 } else if (result->Opcode() == Op_SCMemProj) { 2762 Node* mem = result->in(0); 2763 Node* adr = NULL; 2764 if (mem->is_LoadStore()) { 2765 adr = mem->in(MemNode::Address); 2766 } else { 2767 assert(mem->Opcode() == Op_EncodeISOArray || 2768 mem->Opcode() == Op_StrCompressedCopy, "sanity"); 2769 adr = mem->in(3); // Memory edge corresponds to destination array 2770 } 2771 const Type *at = igvn->type(adr); 2772 if (at != Type::TOP) { 2773 assert(at->isa_ptr() != NULL, "pointer type required."); 2774 int idx = C->get_alias_index(at->is_ptr()); 2775 if (idx == alias_idx) { 2776 // Assert in debug mode 2777 assert(false, "Object is not scalar replaceable if a LoadStore node accesses its field"); 2778 break; // In product mode return SCMemProj node 2779 } 2780 } 2781 result = mem->in(MemNode::Memory); 2782 } else if (result->Opcode() == Op_StrInflatedCopy) { 2783 Node* adr = result->in(3); // Memory edge corresponds to destination array 2784 const Type *at = igvn->type(adr); 2785 if (at != Type::TOP) { 2786 assert(at->isa_ptr() != NULL, "pointer type required."); 2787 int idx = C->get_alias_index(at->is_ptr()); 2788 if (idx == alias_idx) { 2789 // Assert in debug mode 2790 assert(false, "Object is not scalar replaceable if a StrInflatedCopy node accesses its field"); 2791 break; // In product mode return SCMemProj node 2792 } 2793 } 2794 result = result->in(MemNode::Memory); 2795 } 2796 } 2797 if (result->is_Phi()) { 2798 PhiNode *mphi = result->as_Phi(); 2799 assert(mphi->bottom_type() == Type::MEMORY, "memory phi required"); 2800 const TypePtr *t = mphi->adr_type(); 2801 if (!is_instance) { 2802 // Push all non-instance Phis on the orig_phis worklist to update inputs 2803 // during Phase 4 if needed. 2804 orig_phis.append_if_missing(mphi); 2805 } else if (C->get_alias_index(t) != alias_idx) { 2806 // Create a new Phi with the specified alias index type. 2807 result = split_memory_phi(mphi, alias_idx, orig_phis); 2808 } 2809 } 2810 // the result is either MemNode, PhiNode, InitializeNode. 2811 return result; 2812 } 2813 2814 // 2815 // Convert the types of unescaped object to instance types where possible, 2816 // propagate the new type information through the graph, and update memory 2817 // edges and MergeMem inputs to reflect the new type. 2818 // 2819 // We start with allocations (and calls which may be allocations) on alloc_worklist. 2820 // The processing is done in 4 phases: 2821 // 2822 // Phase 1: Process possible allocations from alloc_worklist. Create instance 2823 // types for the CheckCastPP for allocations where possible. 2824 // Propagate the new types through users as follows: 2825 // casts and Phi: push users on alloc_worklist 2826 // AddP: cast Base and Address inputs to the instance type 2827 // push any AddP users on alloc_worklist and push any memnode 2828 // users onto memnode_worklist. 2829 // Phase 2: Process MemNode's from memnode_worklist. compute new address type and 2830 // search the Memory chain for a store with the appropriate type 2831 // address type. If a Phi is found, create a new version with 2832 // the appropriate memory slices from each of the Phi inputs. 2833 // For stores, process the users as follows: 2834 // MemNode: push on memnode_worklist 2835 // MergeMem: push on mergemem_worklist 2836 // Phase 3: Process MergeMem nodes from mergemem_worklist. Walk each memory slice 2837 // moving the first node encountered of each instance type to the 2838 // the input corresponding to its alias index. 2839 // appropriate memory slice. 2840 // Phase 4: Update the inputs of non-instance memory Phis and the Memory input of memnodes. 2841 // 2842 // In the following example, the CheckCastPP nodes are the cast of allocation 2843 // results and the allocation of node 29 is unescaped and eligible to be an 2844 // instance type. 2845 // 2846 // We start with: 2847 // 2848 // 7 Parm #memory 2849 // 10 ConI "12" 2850 // 19 CheckCastPP "Foo" 2851 // 20 AddP _ 19 19 10 Foo+12 alias_index=4 2852 // 29 CheckCastPP "Foo" 2853 // 30 AddP _ 29 29 10 Foo+12 alias_index=4 2854 // 2855 // 40 StoreP 25 7 20 ... alias_index=4 2856 // 50 StoreP 35 40 30 ... alias_index=4 2857 // 60 StoreP 45 50 20 ... alias_index=4 2858 // 70 LoadP _ 60 30 ... alias_index=4 2859 // 80 Phi 75 50 60 Memory alias_index=4 2860 // 90 LoadP _ 80 30 ... alias_index=4 2861 // 100 LoadP _ 80 20 ... alias_index=4 2862 // 2863 // 2864 // Phase 1 creates an instance type for node 29 assigning it an instance id of 24 2865 // and creating a new alias index for node 30. This gives: 2866 // 2867 // 7 Parm #memory 2868 // 10 ConI "12" 2869 // 19 CheckCastPP "Foo" 2870 // 20 AddP _ 19 19 10 Foo+12 alias_index=4 2871 // 29 CheckCastPP "Foo" iid=24 2872 // 30 AddP _ 29 29 10 Foo+12 alias_index=6 iid=24 2873 // 2874 // 40 StoreP 25 7 20 ... alias_index=4 2875 // 50 StoreP 35 40 30 ... alias_index=6 2876 // 60 StoreP 45 50 20 ... alias_index=4 2877 // 70 LoadP _ 60 30 ... alias_index=6 2878 // 80 Phi 75 50 60 Memory alias_index=4 2879 // 90 LoadP _ 80 30 ... alias_index=6 2880 // 100 LoadP _ 80 20 ... alias_index=4 2881 // 2882 // In phase 2, new memory inputs are computed for the loads and stores, 2883 // And a new version of the phi is created. In phase 4, the inputs to 2884 // node 80 are updated and then the memory nodes are updated with the 2885 // values computed in phase 2. This results in: 2886 // 2887 // 7 Parm #memory 2888 // 10 ConI "12" 2889 // 19 CheckCastPP "Foo" 2890 // 20 AddP _ 19 19 10 Foo+12 alias_index=4 2891 // 29 CheckCastPP "Foo" iid=24 2892 // 30 AddP _ 29 29 10 Foo+12 alias_index=6 iid=24 2893 // 2894 // 40 StoreP 25 7 20 ... alias_index=4 2895 // 50 StoreP 35 7 30 ... alias_index=6 2896 // 60 StoreP 45 40 20 ... alias_index=4 2897 // 70 LoadP _ 50 30 ... alias_index=6 2898 // 80 Phi 75 40 60 Memory alias_index=4 2899 // 120 Phi 75 50 50 Memory alias_index=6 2900 // 90 LoadP _ 120 30 ... alias_index=6 2901 // 100 LoadP _ 80 20 ... alias_index=4 2902 // 2903 void ConnectionGraph::split_unique_types(GrowableArray<Node *> &alloc_worklist, GrowableArray<ArrayCopyNode*> &arraycopy_worklist) { 2904 GrowableArray<Node *> memnode_worklist; 2905 GrowableArray<PhiNode *> orig_phis; 2906 PhaseIterGVN *igvn = _igvn; 2907 uint new_index_start = (uint) _compile->num_alias_types(); 2908 Arena* arena = Thread::current()->resource_area(); 2909 VectorSet visited(arena); 2910 ideal_nodes.clear(); // Reset for use with set_map/get_map. 2911 uint unique_old = _compile->unique(); 2912 2913 // Phase 1: Process possible allocations from alloc_worklist. 2914 // Create instance types for the CheckCastPP for allocations where possible. 2915 // 2916 // (Note: don't forget to change the order of the second AddP node on 2917 // the alloc_worklist if the order of the worklist processing is changed, 2918 // see the comment in find_second_addp().) 2919 // 2920 while (alloc_worklist.length() != 0) { 2921 Node *n = alloc_worklist.pop(); 2922 uint ni = n->_idx; 2923 if (n->is_Call()) { 2924 CallNode *alloc = n->as_Call(); 2925 // copy escape information to call node 2926 PointsToNode* ptn = ptnode_adr(alloc->_idx); 2927 PointsToNode::EscapeState es = ptn->escape_state(); 2928 // We have an allocation or call which returns a Java object, 2929 // see if it is unescaped. 2930 if (es != PointsToNode::NoEscape || !ptn->scalar_replaceable()) 2931 continue; 2932 // Find CheckCastPP for the allocate or for the return value of a call 2933 n = alloc->result_cast(); 2934 if (n == NULL) { // No uses except Initialize node 2935 if (alloc->is_Allocate()) { 2936 // Set the scalar_replaceable flag for allocation 2937 // so it could be eliminated if it has no uses. 2938 alloc->as_Allocate()->_is_scalar_replaceable = true; 2939 } 2940 if (alloc->is_CallStaticJava()) { 2941 // Set the scalar_replaceable flag for boxing method 2942 // so it could be eliminated if it has no uses. 2943 alloc->as_CallStaticJava()->_is_scalar_replaceable = true; 2944 } 2945 continue; 2946 } 2947 if (!n->is_CheckCastPP()) { // not unique CheckCastPP. 2948 assert(!alloc->is_Allocate(), "allocation should have unique type"); 2949 continue; 2950 } 2951 2952 // The inline code for Object.clone() casts the allocation result to 2953 // java.lang.Object and then to the actual type of the allocated 2954 // object. Detect this case and use the second cast. 2955 // Also detect j.l.reflect.Array.newInstance(jobject, jint) case when 2956 // the allocation result is cast to java.lang.Object and then 2957 // to the actual Array type. 2958 if (alloc->is_Allocate() && n->as_Type()->type() == TypeInstPtr::NOTNULL 2959 && (alloc->is_AllocateArray() || 2960 igvn->type(alloc->in(AllocateNode::KlassNode)) != TypeKlassPtr::OBJECT)) { 2961 Node *cast2 = NULL; 2962 for (DUIterator_Fast imax, i = n->fast_outs(imax); i < imax; i++) { 2963 Node *use = n->fast_out(i); 2964 if (use->is_CheckCastPP()) { 2965 cast2 = use; 2966 break; 2967 } 2968 } 2969 if (cast2 != NULL) { 2970 n = cast2; 2971 } else { 2972 // Non-scalar replaceable if the allocation type is unknown statically 2973 // (reflection allocation), the object can't be restored during 2974 // deoptimization without precise type. 2975 continue; 2976 } 2977 } 2978 2979 const TypeOopPtr *t = igvn->type(n)->isa_oopptr(); 2980 if (t == NULL) 2981 continue; // not a TypeOopPtr 2982 if (!t->klass_is_exact()) 2983 continue; // not an unique type 2984 2985 if (alloc->is_Allocate()) { 2986 // Set the scalar_replaceable flag for allocation 2987 // so it could be eliminated. 2988 alloc->as_Allocate()->_is_scalar_replaceable = true; 2989 } 2990 if (alloc->is_CallStaticJava()) { 2991 // Set the scalar_replaceable flag for boxing method 2992 // so it could be eliminated. 2993 alloc->as_CallStaticJava()->_is_scalar_replaceable = true; 2994 } 2995 set_escape_state(ptnode_adr(n->_idx), es); // CheckCastPP escape state 2996 // in order for an object to be scalar-replaceable, it must be: 2997 // - a direct allocation (not a call returning an object) 2998 // - non-escaping 2999 // - eligible to be a unique type 3000 // - not determined to be ineligible by escape analysis 3001 set_map(alloc, n); 3002 set_map(n, alloc); 3003 const TypeOopPtr* tinst = t->cast_to_instance_id(ni); 3004 igvn->hash_delete(n); 3005 igvn->set_type(n, tinst); 3006 n->raise_bottom_type(tinst); 3007 igvn->hash_insert(n); 3008 record_for_optimizer(n); 3009 if (alloc->is_Allocate() && (t->isa_instptr() || t->isa_aryptr())) { 3010 3011 // First, put on the worklist all Field edges from Connection Graph 3012 // which is more accurate than putting immediate users from Ideal Graph. 3013 for (EdgeIterator e(ptn); e.has_next(); e.next()) { 3014 PointsToNode* tgt = e.get(); 3015 if (tgt->is_Arraycopy()) { 3016 continue; 3017 } 3018 Node* use = tgt->ideal_node(); 3019 assert(tgt->is_Field() && use->is_AddP(), 3020 "only AddP nodes are Field edges in CG"); 3021 if (use->outcnt() > 0) { // Don't process dead nodes 3022 Node* addp2 = find_second_addp(use, use->in(AddPNode::Base)); 3023 if (addp2 != NULL) { 3024 assert(alloc->is_AllocateArray(),"array allocation was expected"); 3025 alloc_worklist.append_if_missing(addp2); 3026 } 3027 alloc_worklist.append_if_missing(use); 3028 } 3029 } 3030 3031 // An allocation may have an Initialize which has raw stores. Scan 3032 // the users of the raw allocation result and push AddP users 3033 // on alloc_worklist. 3034 Node *raw_result = alloc->proj_out_or_null(TypeFunc::Parms); 3035 assert (raw_result != NULL, "must have an allocation result"); 3036 for (DUIterator_Fast imax, i = raw_result->fast_outs(imax); i < imax; i++) { 3037 Node *use = raw_result->fast_out(i); 3038 if (use->is_AddP() && use->outcnt() > 0) { // Don't process dead nodes 3039 Node* addp2 = find_second_addp(use, raw_result); 3040 if (addp2 != NULL) { 3041 assert(alloc->is_AllocateArray(),"array allocation was expected"); 3042 alloc_worklist.append_if_missing(addp2); 3043 } 3044 alloc_worklist.append_if_missing(use); 3045 } else if (use->is_MemBar()) { 3046 memnode_worklist.append_if_missing(use); 3047 } 3048 } 3049 } 3050 } else if (n->is_AddP()) { 3051 JavaObjectNode* jobj = unique_java_object(get_addp_base(n)); 3052 if (jobj == NULL || jobj == phantom_obj) { 3053 #ifdef ASSERT 3054 ptnode_adr(get_addp_base(n)->_idx)->dump(); 3055 ptnode_adr(n->_idx)->dump(); 3056 assert(jobj != NULL && jobj != phantom_obj, "escaped allocation"); 3057 #endif 3058 _compile->record_failure(C2Compiler::retry_no_escape_analysis()); 3059 return; 3060 } 3061 Node *base = get_map(jobj->idx()); // CheckCastPP node 3062 if (!split_AddP(n, base)) continue; // wrong type from dead path 3063 } else if (n->is_Phi() || 3064 n->is_CheckCastPP() || 3065 n->is_EncodeP() || 3066 n->is_DecodeN() || 3067 (n->is_ConstraintCast() && n->Opcode() == Op_CastPP)) { 3068 if (visited.test_set(n->_idx)) { 3069 assert(n->is_Phi(), "loops only through Phi's"); 3070 continue; // already processed 3071 } 3072 JavaObjectNode* jobj = unique_java_object(n); 3073 if (jobj == NULL || jobj == phantom_obj) { 3074 #ifdef ASSERT 3075 ptnode_adr(n->_idx)->dump(); 3076 assert(jobj != NULL && jobj != phantom_obj, "escaped allocation"); 3077 #endif 3078 _compile->record_failure(C2Compiler::retry_no_escape_analysis()); 3079 return; 3080 } else { 3081 Node *val = get_map(jobj->idx()); // CheckCastPP node 3082 TypeNode *tn = n->as_Type(); 3083 const TypeOopPtr* tinst = igvn->type(val)->isa_oopptr(); 3084 assert(tinst != NULL && tinst->is_known_instance() && 3085 tinst->instance_id() == jobj->idx() , "instance type expected."); 3086 3087 const Type *tn_type = igvn->type(tn); 3088 const TypeOopPtr *tn_t; 3089 if (tn_type->isa_narrowoop()) { 3090 tn_t = tn_type->make_ptr()->isa_oopptr(); 3091 } else { 3092 tn_t = tn_type->isa_oopptr(); 3093 } 3094 if (tn_t != NULL && tinst->klass()->is_subtype_of(tn_t->klass())) { 3095 if (tn_type->isa_narrowoop()) { 3096 tn_type = tinst->make_narrowoop(); 3097 } else { 3098 tn_type = tinst; 3099 } 3100 igvn->hash_delete(tn); 3101 igvn->set_type(tn, tn_type); 3102 tn->set_type(tn_type); 3103 igvn->hash_insert(tn); 3104 record_for_optimizer(n); 3105 } else { 3106 assert(tn_type == TypePtr::NULL_PTR || 3107 tn_t != NULL && !tinst->klass()->is_subtype_of(tn_t->klass()), 3108 "unexpected type"); 3109 continue; // Skip dead path with different type 3110 } 3111 } 3112 } else { 3113 debug_only(n->dump();) 3114 assert(false, "EA: unexpected node"); 3115 continue; 3116 } 3117 // push allocation's users on appropriate worklist 3118 for (DUIterator_Fast imax, i = n->fast_outs(imax); i < imax; i++) { 3119 Node *use = n->fast_out(i); 3120 if(use->is_Mem() && use->in(MemNode::Address) == n) { 3121 // Load/store to instance's field 3122 memnode_worklist.append_if_missing(use); 3123 } else if (use->is_MemBar()) { 3124 if (use->in(TypeFunc::Memory) == n) { // Ignore precedent edge 3125 memnode_worklist.append_if_missing(use); 3126 } 3127 } else if (use->is_AddP() && use->outcnt() > 0) { // No dead nodes 3128 Node* addp2 = find_second_addp(use, n); 3129 if (addp2 != NULL) { 3130 alloc_worklist.append_if_missing(addp2); 3131 } 3132 alloc_worklist.append_if_missing(use); 3133 } else if (use->is_Phi() || 3134 use->is_CheckCastPP() || 3135 use->is_EncodeNarrowPtr() || 3136 use->is_DecodeNarrowPtr() || 3137 (use->is_ConstraintCast() && use->Opcode() == Op_CastPP)) { 3138 alloc_worklist.append_if_missing(use); 3139 #ifdef ASSERT 3140 } else if (use->is_Mem()) { 3141 assert(use->in(MemNode::Address) != n, "EA: missing allocation reference path"); 3142 } else if (use->is_MergeMem()) { 3143 assert(_mergemem_worklist.contains(use->as_MergeMem()), "EA: missing MergeMem node in the worklist"); 3144 } else if (use->is_SafePoint()) { 3145 // Look for MergeMem nodes for calls which reference unique allocation 3146 // (through CheckCastPP nodes) even for debug info. 3147 Node* m = use->in(TypeFunc::Memory); 3148 if (m->is_MergeMem()) { 3149 assert(_mergemem_worklist.contains(m->as_MergeMem()), "EA: missing MergeMem node in the worklist"); 3150 } 3151 } else if (use->Opcode() == Op_EncodeISOArray) { 3152 if (use->in(MemNode::Memory) == n || use->in(3) == n) { 3153 // EncodeISOArray overwrites destination array 3154 memnode_worklist.append_if_missing(use); 3155 } 3156 } else { 3157 uint op = use->Opcode(); 3158 if ((op == Op_StrCompressedCopy || op == Op_StrInflatedCopy) && 3159 (use->in(MemNode::Memory) == n)) { 3160 // They overwrite memory edge corresponding to destination array, 3161 memnode_worklist.append_if_missing(use); 3162 } else if (!(op == Op_CmpP || op == Op_Conv2B || 3163 op == Op_CastP2X || op == Op_StoreCM || 3164 op == Op_FastLock || op == Op_AryEq || op == Op_StrComp || op == Op_HasNegatives || 3165 op == Op_StrCompressedCopy || op == Op_StrInflatedCopy || 3166 op == Op_StrEquals || op == Op_StrIndexOf || op == Op_StrIndexOfChar)) { 3167 n->dump(); 3168 use->dump(); 3169 assert(false, "EA: missing allocation reference path"); 3170 } 3171 #endif 3172 } 3173 } 3174 3175 } 3176 3177 // Go over all ArrayCopy nodes and if one of the inputs has a unique 3178 // type, record it in the ArrayCopy node so we know what memory this 3179 // node uses/modified. 3180 for (int next = 0; next < arraycopy_worklist.length(); next++) { 3181 ArrayCopyNode* ac = arraycopy_worklist.at(next); 3182 Node* dest = ac->in(ArrayCopyNode::Dest); 3183 if (dest->is_AddP()) { 3184 dest = get_addp_base(dest); 3185 } 3186 JavaObjectNode* jobj = unique_java_object(dest); 3187 if (jobj != NULL) { 3188 Node *base = get_map(jobj->idx()); 3189 if (base != NULL) { 3190 const TypeOopPtr *base_t = _igvn->type(base)->isa_oopptr(); 3191 ac->_dest_type = base_t; 3192 } 3193 } 3194 Node* src = ac->in(ArrayCopyNode::Src); 3195 if (src->is_AddP()) { 3196 src = get_addp_base(src); 3197 } 3198 jobj = unique_java_object(src); 3199 if (jobj != NULL) { 3200 Node* base = get_map(jobj->idx()); 3201 if (base != NULL) { 3202 const TypeOopPtr *base_t = _igvn->type(base)->isa_oopptr(); 3203 ac->_src_type = base_t; 3204 } 3205 } 3206 } 3207 3208 // New alias types were created in split_AddP(). 3209 uint new_index_end = (uint) _compile->num_alias_types(); 3210 assert(unique_old == _compile->unique(), "there should be no new ideal nodes after Phase 1"); 3211 3212 // Phase 2: Process MemNode's from memnode_worklist. compute new address type and 3213 // compute new values for Memory inputs (the Memory inputs are not 3214 // actually updated until phase 4.) 3215 if (memnode_worklist.length() == 0) 3216 return; // nothing to do 3217 while (memnode_worklist.length() != 0) { 3218 Node *n = memnode_worklist.pop(); 3219 if (visited.test_set(n->_idx)) 3220 continue; 3221 if (n->is_Phi() || n->is_ClearArray()) { 3222 // we don't need to do anything, but the users must be pushed 3223 } else if (n->is_MemBar()) { // Initialize, MemBar nodes 3224 // we don't need to do anything, but the users must be pushed 3225 n = n->as_MemBar()->proj_out_or_null(TypeFunc::Memory); 3226 if (n == NULL) 3227 continue; 3228 } else if (n->Opcode() == Op_StrCompressedCopy || 3229 n->Opcode() == Op_EncodeISOArray) { 3230 // get the memory projection 3231 n = n->find_out_with(Op_SCMemProj); 3232 assert(n != NULL && n->Opcode() == Op_SCMemProj, "memory projection required"); 3233 } else { 3234 assert(n->is_Mem(), "memory node required."); 3235 Node *addr = n->in(MemNode::Address); 3236 const Type *addr_t = igvn->type(addr); 3237 if (addr_t == Type::TOP) 3238 continue; 3239 assert (addr_t->isa_ptr() != NULL, "pointer type required."); 3240 int alias_idx = _compile->get_alias_index(addr_t->is_ptr()); 3241 assert ((uint)alias_idx < new_index_end, "wrong alias index"); 3242 Node *mem = find_inst_mem(n->in(MemNode::Memory), alias_idx, orig_phis); 3243 if (_compile->failing()) { 3244 return; 3245 } 3246 if (mem != n->in(MemNode::Memory)) { 3247 // We delay the memory edge update since we need old one in 3248 // MergeMem code below when instances memory slices are separated. 3249 set_map(n, mem); 3250 } 3251 if (n->is_Load()) { 3252 continue; // don't push users 3253 } else if (n->is_LoadStore()) { 3254 // get the memory projection 3255 n = n->find_out_with(Op_SCMemProj); 3256 assert(n != NULL && n->Opcode() == Op_SCMemProj, "memory projection required"); 3257 } 3258 } 3259 // push user on appropriate worklist 3260 for (DUIterator_Fast imax, i = n->fast_outs(imax); i < imax; i++) { 3261 Node *use = n->fast_out(i); 3262 if (use->is_Phi() || use->is_ClearArray()) { 3263 memnode_worklist.append_if_missing(use); 3264 } else if (use->is_Mem() && use->in(MemNode::Memory) == n) { 3265 if (use->Opcode() == Op_StoreCM) // Ignore cardmark stores 3266 continue; 3267 memnode_worklist.append_if_missing(use); 3268 } else if (use->is_MemBar()) { 3269 if (use->in(TypeFunc::Memory) == n) { // Ignore precedent edge 3270 memnode_worklist.append_if_missing(use); 3271 } 3272 #ifdef ASSERT 3273 } else if(use->is_Mem()) { 3274 assert(use->in(MemNode::Memory) != n, "EA: missing memory path"); 3275 } else if (use->is_MergeMem()) { 3276 assert(_mergemem_worklist.contains(use->as_MergeMem()), "EA: missing MergeMem node in the worklist"); 3277 } else if (use->Opcode() == Op_EncodeISOArray) { 3278 if (use->in(MemNode::Memory) == n || use->in(3) == n) { 3279 // EncodeISOArray overwrites destination array 3280 memnode_worklist.append_if_missing(use); 3281 } 3282 } else { 3283 uint op = use->Opcode(); 3284 if ((use->in(MemNode::Memory) == n) && 3285 (op == Op_StrCompressedCopy || op == Op_StrInflatedCopy)) { 3286 // They overwrite memory edge corresponding to destination array, 3287 memnode_worklist.append_if_missing(use); 3288 } else if (!(op == Op_StoreCM || 3289 (op == Op_CallLeaf && use->as_CallLeaf()->_name != NULL && 3290 strcmp(use->as_CallLeaf()->_name, "g1_wb_pre") == 0) || 3291 op == Op_AryEq || op == Op_StrComp || op == Op_HasNegatives || 3292 op == Op_StrCompressedCopy || op == Op_StrInflatedCopy || 3293 op == Op_StrEquals || op == Op_StrIndexOf || op == Op_StrIndexOfChar)) { 3294 n->dump(); 3295 use->dump(); 3296 assert(false, "EA: missing memory path"); 3297 } 3298 #endif 3299 } 3300 } 3301 } 3302 3303 // Phase 3: Process MergeMem nodes from mergemem_worklist. 3304 // Walk each memory slice moving the first node encountered of each 3305 // instance type to the the input corresponding to its alias index. 3306 uint length = _mergemem_worklist.length(); 3307 for( uint next = 0; next < length; ++next ) { 3308 MergeMemNode* nmm = _mergemem_worklist.at(next); 3309 assert(!visited.test_set(nmm->_idx), "should not be visited before"); 3310 // Note: we don't want to use MergeMemStream here because we only want to 3311 // scan inputs which exist at the start, not ones we add during processing. 3312 // Note 2: MergeMem may already contains instance memory slices added 3313 // during find_inst_mem() call when memory nodes were processed above. 3314 igvn->hash_delete(nmm); 3315 uint nslices = MIN2(nmm->req(), new_index_start); 3316 for (uint i = Compile::AliasIdxRaw+1; i < nslices; i++) { 3317 Node* mem = nmm->in(i); 3318 Node* cur = NULL; 3319 if (mem == NULL || mem->is_top()) 3320 continue; 3321 // First, update mergemem by moving memory nodes to corresponding slices 3322 // if their type became more precise since this mergemem was created. 3323 while (mem->is_Mem()) { 3324 const Type *at = igvn->type(mem->in(MemNode::Address)); 3325 if (at != Type::TOP) { 3326 assert (at->isa_ptr() != NULL, "pointer type required."); 3327 uint idx = (uint)_compile->get_alias_index(at->is_ptr()); 3328 if (idx == i) { 3329 if (cur == NULL) 3330 cur = mem; 3331 } else { 3332 if (idx >= nmm->req() || nmm->is_empty_memory(nmm->in(idx))) { 3333 nmm->set_memory_at(idx, mem); 3334 } 3335 } 3336 } 3337 mem = mem->in(MemNode::Memory); 3338 } 3339 nmm->set_memory_at(i, (cur != NULL) ? cur : mem); 3340 // Find any instance of the current type if we haven't encountered 3341 // already a memory slice of the instance along the memory chain. 3342 for (uint ni = new_index_start; ni < new_index_end; ni++) { 3343 if((uint)_compile->get_general_index(ni) == i) { 3344 Node *m = (ni >= nmm->req()) ? nmm->empty_memory() : nmm->in(ni); 3345 if (nmm->is_empty_memory(m)) { 3346 Node* result = find_inst_mem(mem, ni, orig_phis); 3347 if (_compile->failing()) { 3348 return; 3349 } 3350 nmm->set_memory_at(ni, result); 3351 } 3352 } 3353 } 3354 } 3355 // Find the rest of instances values 3356 for (uint ni = new_index_start; ni < new_index_end; ni++) { 3357 const TypeOopPtr *tinst = _compile->get_adr_type(ni)->isa_oopptr(); 3358 Node* result = step_through_mergemem(nmm, ni, tinst); 3359 if (result == nmm->base_memory()) { 3360 // Didn't find instance memory, search through general slice recursively. 3361 result = nmm->memory_at(_compile->get_general_index(ni)); 3362 result = find_inst_mem(result, ni, orig_phis); 3363 if (_compile->failing()) { 3364 return; 3365 } 3366 nmm->set_memory_at(ni, result); 3367 } 3368 } 3369 igvn->hash_insert(nmm); 3370 record_for_optimizer(nmm); 3371 } 3372 3373 // Phase 4: Update the inputs of non-instance memory Phis and 3374 // the Memory input of memnodes 3375 // First update the inputs of any non-instance Phi's from 3376 // which we split out an instance Phi. Note we don't have 3377 // to recursively process Phi's encounted on the input memory 3378 // chains as is done in split_memory_phi() since they will 3379 // also be processed here. 3380 for (int j = 0; j < orig_phis.length(); j++) { 3381 PhiNode *phi = orig_phis.at(j); 3382 int alias_idx = _compile->get_alias_index(phi->adr_type()); 3383 igvn->hash_delete(phi); 3384 for (uint i = 1; i < phi->req(); i++) { 3385 Node *mem = phi->in(i); 3386 Node *new_mem = find_inst_mem(mem, alias_idx, orig_phis); 3387 if (_compile->failing()) { 3388 return; 3389 } 3390 if (mem != new_mem) { 3391 phi->set_req(i, new_mem); 3392 } 3393 } 3394 igvn->hash_insert(phi); 3395 record_for_optimizer(phi); 3396 } 3397 3398 // Update the memory inputs of MemNodes with the value we computed 3399 // in Phase 2 and move stores memory users to corresponding memory slices. 3400 // Disable memory split verification code until the fix for 6984348. 3401 // Currently it produces false negative results since it does not cover all cases. 3402 #if 0 // ifdef ASSERT 3403 visited.Reset(); 3404 Node_Stack old_mems(arena, _compile->unique() >> 2); 3405 #endif 3406 for (uint i = 0; i < ideal_nodes.size(); i++) { 3407 Node* n = ideal_nodes.at(i); 3408 Node* nmem = get_map(n->_idx); 3409 assert(nmem != NULL, "sanity"); 3410 if (n->is_Mem()) { 3411 #if 0 // ifdef ASSERT 3412 Node* old_mem = n->in(MemNode::Memory); 3413 if (!visited.test_set(old_mem->_idx)) { 3414 old_mems.push(old_mem, old_mem->outcnt()); 3415 } 3416 #endif 3417 assert(n->in(MemNode::Memory) != nmem, "sanity"); 3418 if (!n->is_Load()) { 3419 // Move memory users of a store first. 3420 move_inst_mem(n, orig_phis); 3421 } 3422 // Now update memory input 3423 igvn->hash_delete(n); 3424 n->set_req(MemNode::Memory, nmem); 3425 igvn->hash_insert(n); 3426 record_for_optimizer(n); 3427 } else { 3428 assert(n->is_Allocate() || n->is_CheckCastPP() || 3429 n->is_AddP() || n->is_Phi(), "unknown node used for set_map()"); 3430 } 3431 } 3432 #if 0 // ifdef ASSERT 3433 // Verify that memory was split correctly 3434 while (old_mems.is_nonempty()) { 3435 Node* old_mem = old_mems.node(); 3436 uint old_cnt = old_mems.index(); 3437 old_mems.pop(); 3438 assert(old_cnt == old_mem->outcnt(), "old mem could be lost"); 3439 } 3440 #endif 3441 } 3442 3443 #ifndef PRODUCT 3444 static const char *node_type_names[] = { 3445 "UnknownType", 3446 "JavaObject", 3447 "LocalVar", 3448 "Field", 3449 "Arraycopy" 3450 }; 3451 3452 static const char *esc_names[] = { 3453 "UnknownEscape", 3454 "NoEscape", 3455 "ArgEscape", 3456 "GlobalEscape" 3457 }; 3458 3459 void PointsToNode::dump(bool print_state) const { 3460 NodeType nt = node_type(); 3461 tty->print("%s ", node_type_names[(int) nt]); 3462 if (print_state) { 3463 EscapeState es = escape_state(); 3464 EscapeState fields_es = fields_escape_state(); 3465 tty->print("%s(%s) ", esc_names[(int)es], esc_names[(int)fields_es]); 3466 if (nt == PointsToNode::JavaObject && !this->scalar_replaceable()) 3467 tty->print("NSR "); 3468 } 3469 if (is_Field()) { 3470 FieldNode* f = (FieldNode*)this; 3471 if (f->is_oop()) 3472 tty->print("oop "); 3473 if (f->offset() > 0) 3474 tty->print("+%d ", f->offset()); 3475 tty->print("("); 3476 for (BaseIterator i(f); i.has_next(); i.next()) { 3477 PointsToNode* b = i.get(); 3478 tty->print(" %d%s", b->idx(),(b->is_JavaObject() ? "P" : "")); 3479 } 3480 tty->print(" )"); 3481 } 3482 tty->print("["); 3483 for (EdgeIterator i(this); i.has_next(); i.next()) { 3484 PointsToNode* e = i.get(); 3485 tty->print(" %d%s%s", e->idx(),(e->is_JavaObject() ? "P" : (e->is_Field() ? "F" : "")), e->is_Arraycopy() ? "cp" : ""); 3486 } 3487 tty->print(" ["); 3488 for (UseIterator i(this); i.has_next(); i.next()) { 3489 PointsToNode* u = i.get(); 3490 bool is_base = false; 3491 if (PointsToNode::is_base_use(u)) { 3492 is_base = true; 3493 u = PointsToNode::get_use_node(u)->as_Field(); 3494 } 3495 tty->print(" %d%s%s", u->idx(), is_base ? "b" : "", u->is_Arraycopy() ? "cp" : ""); 3496 } 3497 tty->print(" ]] "); 3498 if (_node == NULL) 3499 tty->print_cr("<null>"); 3500 else 3501 _node->dump(); 3502 } 3503 3504 void ConnectionGraph::dump(GrowableArray<PointsToNode*>& ptnodes_worklist) { 3505 bool first = true; 3506 int ptnodes_length = ptnodes_worklist.length(); 3507 for (int i = 0; i < ptnodes_length; i++) { 3508 PointsToNode *ptn = ptnodes_worklist.at(i); 3509 if (ptn == NULL || !ptn->is_JavaObject()) 3510 continue; 3511 PointsToNode::EscapeState es = ptn->escape_state(); 3512 if ((es != PointsToNode::NoEscape) && !Verbose) { 3513 continue; 3514 } 3515 Node* n = ptn->ideal_node(); 3516 if (n->is_Allocate() || (n->is_CallStaticJava() && 3517 n->as_CallStaticJava()->is_boxing_method())) { 3518 if (first) { 3519 tty->cr(); 3520 tty->print("======== Connection graph for "); 3521 _compile->method()->print_short_name(); 3522 tty->cr(); 3523 first = false; 3524 } 3525 ptn->dump(); 3526 // Print all locals and fields which reference this allocation 3527 for (UseIterator j(ptn); j.has_next(); j.next()) { 3528 PointsToNode* use = j.get(); 3529 if (use->is_LocalVar()) { 3530 use->dump(Verbose); 3531 } else if (Verbose) { 3532 use->dump(); 3533 } 3534 } 3535 tty->cr(); 3536 } 3537 } 3538 } 3539 #endif