1 /* 2 * Copyright (c) 2005, 2013, Oracle and/or its affiliates. All rights reserved. 3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. 4 * 5 * This code is free software; you can redistribute it and/or modify it 6 * under the terms of the GNU General Public License version 2 only, as 7 * published by the Free Software Foundation. 8 * 9 * This code is distributed in the hope that it will be useful, but WITHOUT 10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 12 * version 2 for more details (a copy is included in the LICENSE file that 13 * accompanied this code). 14 * 15 * You should have received a copy of the GNU General Public License version 16 * 2 along with this work; if not, write to the Free Software Foundation, 17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. 18 * 19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA 20 * or visit www.oracle.com if you need additional information or have any 21 * questions. 22 * 23 */ 24 25 #include "precompiled.hpp" 26 #include "ci/bcEscapeAnalyzer.hpp" 27 #include "compiler/compileLog.hpp" 28 #include "libadt/vectset.hpp" 29 #include "memory/allocation.hpp" 30 #include "opto/c2compiler.hpp" 31 #include "opto/callnode.hpp" 32 #include "opto/cfgnode.hpp" 33 #include "opto/compile.hpp" 34 #include "opto/escape.hpp" 35 #include "opto/phaseX.hpp" 36 #include "opto/rootnode.hpp" 37 38 ConnectionGraph::ConnectionGraph(Compile * C, PhaseIterGVN *igvn) : 39 _nodes(C->comp_arena(), C->unique(), C->unique(), NULL), 40 _collecting(true), 41 _verify(false), 42 _compile(C), 43 _igvn(igvn), 44 _node_map(C->comp_arena()) { 45 // Add unknown java object. 46 add_java_object(C->top(), PointsToNode::GlobalEscape); 47 phantom_obj = ptnode_adr(C->top()->_idx)->as_JavaObject(); 48 // Add ConP(#NULL) and ConN(#NULL) nodes. 49 Node* oop_null = igvn->zerocon(T_OBJECT); 50 assert(oop_null->_idx < nodes_size(), "should be created already"); 51 add_java_object(oop_null, PointsToNode::NoEscape); 52 null_obj = ptnode_adr(oop_null->_idx)->as_JavaObject(); 53 if (UseCompressedOops) { 54 Node* noop_null = igvn->zerocon(T_NARROWOOP); 55 assert(noop_null->_idx < nodes_size(), "should be created already"); 56 map_ideal_node(noop_null, null_obj); 57 } 58 _pcmp_neq = NULL; // Should be initialized 59 _pcmp_eq = NULL; 60 } 61 62 bool ConnectionGraph::has_candidates(Compile *C) { 63 // EA brings benefits only when the code has allocations and/or locks which 64 // are represented by ideal Macro nodes. 65 int cnt = C->macro_count(); 66 for (int i = 0; i < cnt; i++) { 67 Node *n = C->macro_node(i); 68 if (n->is_Allocate()) 69 return true; 70 if (n->is_Lock()) { 71 Node* obj = n->as_Lock()->obj_node()->uncast(); 72 if (!(obj->is_Parm() || obj->is_Con())) 73 return true; 74 } 75 if (n->is_CallStaticJava() && 76 n->as_CallStaticJava()->is_boxing_method()) { 77 return true; 78 } 79 } 80 return false; 81 } 82 83 void ConnectionGraph::do_analysis(Compile *C, PhaseIterGVN *igvn) { 84 Compile::TracePhase t2("escapeAnalysis", &Phase::_t_escapeAnalysis, true); 85 ResourceMark rm; 86 87 // Add ConP#NULL and ConN#NULL nodes before ConnectionGraph construction 88 // to create space for them in ConnectionGraph::_nodes[]. 89 Node* oop_null = igvn->zerocon(T_OBJECT); 90 Node* noop_null = igvn->zerocon(T_NARROWOOP); 91 ConnectionGraph* congraph = new(C->comp_arena()) ConnectionGraph(C, igvn); 92 // Perform escape analysis 93 if (congraph->compute_escape()) { 94 // There are non escaping objects. 95 C->set_congraph(congraph); 96 } 97 // Cleanup. 98 if (oop_null->outcnt() == 0) 99 igvn->hash_delete(oop_null); 100 if (noop_null->outcnt() == 0) 101 igvn->hash_delete(noop_null); 102 } 103 104 bool ConnectionGraph::compute_escape() { 105 Compile* C = _compile; 106 PhaseGVN* igvn = _igvn; 107 108 // Worklists used by EA. 109 Unique_Node_List delayed_worklist; 110 GrowableArray<Node*> alloc_worklist; 111 GrowableArray<Node*> ptr_cmp_worklist; 112 GrowableArray<Node*> storestore_worklist; 113 GrowableArray<PointsToNode*> ptnodes_worklist; 114 GrowableArray<JavaObjectNode*> java_objects_worklist; 115 GrowableArray<JavaObjectNode*> non_escaped_worklist; 116 GrowableArray<FieldNode*> oop_fields_worklist; 117 DEBUG_ONLY( GrowableArray<Node*> addp_worklist; ) 118 119 { Compile::TracePhase t3("connectionGraph", &Phase::_t_connectionGraph, true); 120 121 // 1. Populate Connection Graph (CG) with PointsTo nodes. 122 ideal_nodes.map(C->live_nodes(), NULL); // preallocate space 123 // Initialize worklist 124 if (C->root() != NULL) { 125 ideal_nodes.push(C->root()); 126 } 127 for( uint next = 0; next < ideal_nodes.size(); ++next ) { 128 Node* n = ideal_nodes.at(next); 129 // Create PointsTo nodes and add them to Connection Graph. Called 130 // only once per ideal node since ideal_nodes is Unique_Node list. 131 add_node_to_connection_graph(n, &delayed_worklist); 132 PointsToNode* ptn = ptnode_adr(n->_idx); 133 if (ptn != NULL) { 134 ptnodes_worklist.append(ptn); 135 if (ptn->is_JavaObject()) { 136 java_objects_worklist.append(ptn->as_JavaObject()); 137 if ((n->is_Allocate() || n->is_CallStaticJava()) && 138 (ptn->escape_state() < PointsToNode::GlobalEscape)) { 139 // Only allocations and java static calls results are interesting. 140 non_escaped_worklist.append(ptn->as_JavaObject()); 141 } 142 } else if (ptn->is_Field() && ptn->as_Field()->is_oop()) { 143 oop_fields_worklist.append(ptn->as_Field()); 144 } 145 } 146 if (n->is_MergeMem()) { 147 // Collect all MergeMem nodes to add memory slices for 148 // scalar replaceable objects in split_unique_types(). 149 _mergemem_worklist.append(n->as_MergeMem()); 150 } else if (OptimizePtrCompare && n->is_Cmp() && 151 (n->Opcode() == Op_CmpP || n->Opcode() == Op_CmpN)) { 152 // Collect compare pointers nodes. 153 ptr_cmp_worklist.append(n); 154 } else if (n->is_MemBarStoreStore()) { 155 // Collect all MemBarStoreStore nodes so that depending on the 156 // escape status of the associated Allocate node some of them 157 // may be eliminated. 158 storestore_worklist.append(n); 159 } else if (n->is_MemBar() && (n->Opcode() == Op_MemBarRelease) && 160 (n->req() > MemBarNode::Precedent)) { 161 record_for_optimizer(n); 162 #ifdef ASSERT 163 } else if (n->is_AddP()) { 164 // Collect address nodes for graph verification. 165 addp_worklist.append(n); 166 #endif 167 } 168 for (DUIterator_Fast imax, i = n->fast_outs(imax); i < imax; i++) { 169 Node* m = n->fast_out(i); // Get user 170 ideal_nodes.push(m); 171 } 172 } 173 if (non_escaped_worklist.length() == 0) { 174 _collecting = false; 175 return false; // Nothing to do. 176 } 177 // Add final simple edges to graph. 178 while(delayed_worklist.size() > 0) { 179 Node* n = delayed_worklist.pop(); 180 add_final_edges(n); 181 } 182 int ptnodes_length = ptnodes_worklist.length(); 183 184 #ifdef ASSERT 185 if (VerifyConnectionGraph) { 186 // Verify that no new simple edges could be created and all 187 // local vars has edges. 188 _verify = true; 189 for (int next = 0; next < ptnodes_length; ++next) { 190 PointsToNode* ptn = ptnodes_worklist.at(next); 191 add_final_edges(ptn->ideal_node()); 192 if (ptn->is_LocalVar() && ptn->edge_count() == 0) { 193 ptn->dump(); 194 assert(ptn->as_LocalVar()->edge_count() > 0, "sanity"); 195 } 196 } 197 _verify = false; 198 } 199 #endif 200 201 // 2. Finish Graph construction by propagating references to all 202 // java objects through graph. 203 if (!complete_connection_graph(ptnodes_worklist, non_escaped_worklist, 204 java_objects_worklist, oop_fields_worklist)) { 205 // All objects escaped or hit time or iterations limits. 206 _collecting = false; 207 return false; 208 } 209 210 // 3. Adjust scalar_replaceable state of nonescaping objects and push 211 // scalar replaceable allocations on alloc_worklist for processing 212 // in split_unique_types(). 213 int non_escaped_length = non_escaped_worklist.length(); 214 for (int next = 0; next < non_escaped_length; next++) { 215 JavaObjectNode* ptn = non_escaped_worklist.at(next); 216 bool noescape = (ptn->escape_state() == PointsToNode::NoEscape); 217 Node* n = ptn->ideal_node(); 218 if (n->is_Allocate()) { 219 n->as_Allocate()->_is_non_escaping = noescape; 220 } 221 if (n->is_CallStaticJava()) { 222 n->as_CallStaticJava()->_is_non_escaping = noescape; 223 } 224 if (noescape && ptn->scalar_replaceable()) { 225 adjust_scalar_replaceable_state(ptn); 226 if (ptn->scalar_replaceable()) { 227 alloc_worklist.append(ptn->ideal_node()); 228 } 229 } 230 } 231 232 #ifdef ASSERT 233 if (VerifyConnectionGraph) { 234 // Verify that graph is complete - no new edges could be added or needed. 235 verify_connection_graph(ptnodes_worklist, non_escaped_worklist, 236 java_objects_worklist, addp_worklist); 237 } 238 assert(C->unique() == nodes_size(), "no new ideal nodes should be added during ConnectionGraph build"); 239 assert(null_obj->escape_state() == PointsToNode::NoEscape && 240 null_obj->edge_count() == 0 && 241 !null_obj->arraycopy_src() && 242 !null_obj->arraycopy_dst(), "sanity"); 243 #endif 244 245 _collecting = false; 246 247 } // TracePhase t3("connectionGraph") 248 249 // 4. Optimize ideal graph based on EA information. 250 bool has_non_escaping_obj = (non_escaped_worklist.length() > 0); 251 if (has_non_escaping_obj) { 252 optimize_ideal_graph(ptr_cmp_worklist, storestore_worklist); 253 } 254 255 #ifndef PRODUCT 256 if (PrintEscapeAnalysis) { 257 dump(ptnodes_worklist); // Dump ConnectionGraph 258 } 259 #endif 260 261 bool has_scalar_replaceable_candidates = (alloc_worklist.length() > 0); 262 #ifdef ASSERT 263 if (VerifyConnectionGraph) { 264 int alloc_length = alloc_worklist.length(); 265 for (int next = 0; next < alloc_length; ++next) { 266 Node* n = alloc_worklist.at(next); 267 PointsToNode* ptn = ptnode_adr(n->_idx); 268 assert(ptn->escape_state() == PointsToNode::NoEscape && ptn->scalar_replaceable(), "sanity"); 269 } 270 } 271 #endif 272 273 // 5. Separate memory graph for scalar replaceable allcations. 274 if (has_scalar_replaceable_candidates && 275 C->AliasLevel() >= 3 && EliminateAllocations) { 276 // Now use the escape information to create unique types for 277 // scalar replaceable objects. 278 split_unique_types(alloc_worklist); 279 if (C->failing()) return false; 280 C->print_method(PHASE_AFTER_EA, 2); 281 282 #ifdef ASSERT 283 } else if (Verbose && (PrintEscapeAnalysis || PrintEliminateAllocations)) { 284 tty->print("=== No allocations eliminated for "); 285 C->method()->print_short_name(); 286 if(!EliminateAllocations) { 287 tty->print(" since EliminateAllocations is off ==="); 288 } else if(!has_scalar_replaceable_candidates) { 289 tty->print(" since there are no scalar replaceable candidates ==="); 290 } else if(C->AliasLevel() < 3) { 291 tty->print(" since AliasLevel < 3 ==="); 292 } 293 tty->cr(); 294 #endif 295 } 296 return has_non_escaping_obj; 297 } 298 299 // Utility function for nodes that load an object 300 void ConnectionGraph::add_objload_to_connection_graph(Node *n, Unique_Node_List *delayed_worklist) { 301 // Using isa_ptr() instead of isa_oopptr() for LoadP and Phi because 302 // ThreadLocal has RawPtr type. 303 const Type* t = _igvn->type(n); 304 if (t->make_ptr() != NULL) { 305 Node* adr = n->in(MemNode::Address); 306 #ifdef ASSERT 307 if (!adr->is_AddP()) { 308 assert(_igvn->type(adr)->isa_rawptr(), "sanity"); 309 } else { 310 assert((ptnode_adr(adr->_idx) == NULL || 311 ptnode_adr(adr->_idx)->as_Field()->is_oop()), "sanity"); 312 } 313 #endif 314 add_local_var_and_edge(n, PointsToNode::NoEscape, 315 adr, delayed_worklist); 316 } 317 } 318 319 // Populate Connection Graph with PointsTo nodes and create simple 320 // connection graph edges. 321 void ConnectionGraph::add_node_to_connection_graph(Node *n, Unique_Node_List *delayed_worklist) { 322 assert(!_verify, "this method sould not be called for verification"); 323 PhaseGVN* igvn = _igvn; 324 uint n_idx = n->_idx; 325 PointsToNode* n_ptn = ptnode_adr(n_idx); 326 if (n_ptn != NULL) 327 return; // No need to redefine PointsTo node during first iteration. 328 329 if (n->is_Call()) { 330 // Arguments to allocation and locking don't escape. 331 if (n->is_AbstractLock()) { 332 // Put Lock and Unlock nodes on IGVN worklist to process them during 333 // first IGVN optimization when escape information is still available. 334 record_for_optimizer(n); 335 } else if (n->is_Allocate()) { 336 add_call_node(n->as_Call()); 337 record_for_optimizer(n); 338 } else { 339 if (n->is_CallStaticJava()) { 340 const char* name = n->as_CallStaticJava()->_name; 341 if (name != NULL && strcmp(name, "uncommon_trap") == 0) 342 return; // Skip uncommon traps 343 } 344 // Don't mark as processed since call's arguments have to be processed. 345 delayed_worklist->push(n); 346 // Check if a call returns an object. 347 if ((n->as_Call()->returns_pointer() && 348 n->as_Call()->proj_out(TypeFunc::Parms) != NULL) || 349 (n->is_CallStaticJava() && 350 n->as_CallStaticJava()->is_boxing_method())) { 351 add_call_node(n->as_Call()); 352 } 353 } 354 return; 355 } 356 // Put this check here to process call arguments since some call nodes 357 // point to phantom_obj. 358 if (n_ptn == phantom_obj || n_ptn == null_obj) 359 return; // Skip predefined nodes. 360 361 int opcode = n->Opcode(); 362 switch (opcode) { 363 case Op_AddP: { 364 Node* base = get_addp_base(n); 365 PointsToNode* ptn_base = ptnode_adr(base->_idx); 366 // Field nodes are created for all field types. They are used in 367 // adjust_scalar_replaceable_state() and split_unique_types(). 368 // Note, non-oop fields will have only base edges in Connection 369 // Graph because such fields are not used for oop loads and stores. 370 int offset = address_offset(n, igvn); 371 add_field(n, PointsToNode::NoEscape, offset); 372 if (ptn_base == NULL) { 373 delayed_worklist->push(n); // Process it later. 374 } else { 375 n_ptn = ptnode_adr(n_idx); 376 add_base(n_ptn->as_Field(), ptn_base); 377 } 378 break; 379 } 380 case Op_CastX2P: { 381 map_ideal_node(n, phantom_obj); 382 break; 383 } 384 case Op_CastPP: 385 case Op_CheckCastPP: 386 case Op_EncodeP: 387 case Op_DecodeN: 388 case Op_EncodePKlass: 389 case Op_DecodeNKlass: { 390 add_local_var_and_edge(n, PointsToNode::NoEscape, 391 n->in(1), delayed_worklist); 392 break; 393 } 394 case Op_CMoveP: { 395 add_local_var(n, PointsToNode::NoEscape); 396 // Do not add edges during first iteration because some could be 397 // not defined yet. 398 delayed_worklist->push(n); 399 break; 400 } 401 case Op_ConP: 402 case Op_ConN: 403 case Op_ConNKlass: { 404 // assume all oop constants globally escape except for null 405 PointsToNode::EscapeState es; 406 const Type* t = igvn->type(n); 407 if (t == TypePtr::NULL_PTR || t == TypeNarrowOop::NULL_PTR) { 408 es = PointsToNode::NoEscape; 409 } else { 410 es = PointsToNode::GlobalEscape; 411 } 412 add_java_object(n, es); 413 break; 414 } 415 case Op_CreateEx: { 416 // assume that all exception objects globally escape 417 add_java_object(n, PointsToNode::GlobalEscape); 418 break; 419 } 420 case Op_LoadKlass: 421 case Op_LoadNKlass: { 422 // Unknown class is loaded 423 map_ideal_node(n, phantom_obj); 424 break; 425 } 426 case Op_LoadP: 427 case Op_LoadN: 428 case Op_LoadPLocked: { 429 add_objload_to_connection_graph(n, delayed_worklist); 430 break; 431 } 432 case Op_Parm: { 433 map_ideal_node(n, phantom_obj); 434 break; 435 } 436 case Op_PartialSubtypeCheck: { 437 // Produces Null or notNull and is used in only in CmpP so 438 // phantom_obj could be used. 439 map_ideal_node(n, phantom_obj); // Result is unknown 440 break; 441 } 442 case Op_Phi: { 443 // Using isa_ptr() instead of isa_oopptr() for LoadP and Phi because 444 // ThreadLocal has RawPtr type. 445 const Type* t = n->as_Phi()->type(); 446 if (t->make_ptr() != NULL) { 447 add_local_var(n, PointsToNode::NoEscape); 448 // Do not add edges during first iteration because some could be 449 // not defined yet. 450 delayed_worklist->push(n); 451 } 452 break; 453 } 454 case Op_Proj: { 455 // we are only interested in the oop result projection from a call 456 if (n->as_Proj()->_con == TypeFunc::Parms && n->in(0)->is_Call() && 457 n->in(0)->as_Call()->returns_pointer()) { 458 add_local_var_and_edge(n, PointsToNode::NoEscape, 459 n->in(0), delayed_worklist); 460 } 461 break; 462 } 463 case Op_Rethrow: // Exception object escapes 464 case Op_Return: { 465 if (n->req() > TypeFunc::Parms && 466 igvn->type(n->in(TypeFunc::Parms))->isa_oopptr()) { 467 // Treat Return value as LocalVar with GlobalEscape escape state. 468 add_local_var_and_edge(n, PointsToNode::GlobalEscape, 469 n->in(TypeFunc::Parms), delayed_worklist); 470 } 471 break; 472 } 473 case Op_GetAndSetP: 474 case Op_GetAndSetN: { 475 add_objload_to_connection_graph(n, delayed_worklist); 476 // fallthrough 477 } 478 case Op_StoreP: 479 case Op_StoreN: 480 case Op_StoreNKlass: 481 case Op_StorePConditional: 482 case Op_CompareAndSwapP: 483 case Op_CompareAndSwapN: { 484 Node* adr = n->in(MemNode::Address); 485 const Type *adr_type = igvn->type(adr); 486 adr_type = adr_type->make_ptr(); 487 if (adr_type == NULL) { 488 break; // skip dead nodes 489 } 490 if (adr_type->isa_oopptr() || 491 (opcode == Op_StoreP || opcode == Op_StoreN || opcode == Op_StoreNKlass) && 492 (adr_type == TypeRawPtr::NOTNULL && 493 adr->in(AddPNode::Address)->is_Proj() && 494 adr->in(AddPNode::Address)->in(0)->is_Allocate())) { 495 delayed_worklist->push(n); // Process it later. 496 #ifdef ASSERT 497 assert(adr->is_AddP(), "expecting an AddP"); 498 if (adr_type == TypeRawPtr::NOTNULL) { 499 // Verify a raw address for a store captured by Initialize node. 500 int offs = (int)igvn->find_intptr_t_con(adr->in(AddPNode::Offset), Type::OffsetBot); 501 assert(offs != Type::OffsetBot, "offset must be a constant"); 502 } 503 #endif 504 } else { 505 // Ignore copy the displaced header to the BoxNode (OSR compilation). 506 if (adr->is_BoxLock()) 507 break; 508 // Stored value escapes in unsafe access. 509 if ((opcode == Op_StoreP) && (adr_type == TypeRawPtr::BOTTOM)) { 510 // Pointer stores in G1 barriers looks like unsafe access. 511 // Ignore such stores to be able scalar replace non-escaping 512 // allocations. 513 if (UseG1GC && adr->is_AddP()) { 514 Node* base = get_addp_base(adr); 515 if (base->Opcode() == Op_LoadP && 516 base->in(MemNode::Address)->is_AddP()) { 517 adr = base->in(MemNode::Address); 518 Node* tls = get_addp_base(adr); 519 if (tls->Opcode() == Op_ThreadLocal) { 520 int offs = (int)igvn->find_intptr_t_con(adr->in(AddPNode::Offset), Type::OffsetBot); 521 if (offs == in_bytes(JavaThread::satb_mark_queue_offset() + 522 PtrQueue::byte_offset_of_buf())) { 523 break; // G1 pre barier previous oop value store. 524 } 525 if (offs == in_bytes(JavaThread::dirty_card_queue_offset() + 526 PtrQueue::byte_offset_of_buf())) { 527 break; // G1 post barier card address store. 528 } 529 } 530 } 531 } 532 delayed_worklist->push(n); // Process unsafe access later. 533 break; 534 } 535 #ifdef ASSERT 536 n->dump(1); 537 assert(false, "not unsafe or G1 barrier raw StoreP"); 538 #endif 539 } 540 break; 541 } 542 case Op_AryEq: 543 case Op_StrComp: 544 case Op_StrEquals: 545 case Op_StrIndexOf: 546 case Op_EncodeISOArray: { 547 add_local_var(n, PointsToNode::ArgEscape); 548 delayed_worklist->push(n); // Process it later. 549 break; 550 } 551 case Op_ThreadLocal: { 552 add_java_object(n, PointsToNode::ArgEscape); 553 break; 554 } 555 default: 556 ; // Do nothing for nodes not related to EA. 557 } 558 return; 559 } 560 561 #ifdef ASSERT 562 #define ELSE_FAIL(name) \ 563 /* Should not be called for not pointer type. */ \ 564 n->dump(1); \ 565 assert(false, name); \ 566 break; 567 #else 568 #define ELSE_FAIL(name) \ 569 break; 570 #endif 571 572 // Add final simple edges to graph. 573 void ConnectionGraph::add_final_edges(Node *n) { 574 PointsToNode* n_ptn = ptnode_adr(n->_idx); 575 #ifdef ASSERT 576 if (_verify && n_ptn->is_JavaObject()) 577 return; // This method does not change graph for JavaObject. 578 #endif 579 580 if (n->is_Call()) { 581 process_call_arguments(n->as_Call()); 582 return; 583 } 584 assert(n->is_Store() || n->is_LoadStore() || 585 (n_ptn != NULL) && (n_ptn->ideal_node() != NULL), 586 "node should be registered already"); 587 int opcode = n->Opcode(); 588 switch (opcode) { 589 case Op_AddP: { 590 Node* base = get_addp_base(n); 591 PointsToNode* ptn_base = ptnode_adr(base->_idx); 592 assert(ptn_base != NULL, "field's base should be registered"); 593 add_base(n_ptn->as_Field(), ptn_base); 594 break; 595 } 596 case Op_CastPP: 597 case Op_CheckCastPP: 598 case Op_EncodeP: 599 case Op_DecodeN: 600 case Op_EncodePKlass: 601 case Op_DecodeNKlass: { 602 add_local_var_and_edge(n, PointsToNode::NoEscape, 603 n->in(1), NULL); 604 break; 605 } 606 case Op_CMoveP: { 607 for (uint i = CMoveNode::IfFalse; i < n->req(); i++) { 608 Node* in = n->in(i); 609 if (in == NULL) 610 continue; // ignore NULL 611 Node* uncast_in = in->uncast(); 612 if (uncast_in->is_top() || uncast_in == n) 613 continue; // ignore top or inputs which go back this node 614 PointsToNode* ptn = ptnode_adr(in->_idx); 615 assert(ptn != NULL, "node should be registered"); 616 add_edge(n_ptn, ptn); 617 } 618 break; 619 } 620 case Op_LoadP: 621 case Op_LoadN: 622 case Op_LoadPLocked: { 623 // Using isa_ptr() instead of isa_oopptr() for LoadP and Phi because 624 // ThreadLocal has RawPtr type. 625 const Type* t = _igvn->type(n); 626 if (t->make_ptr() != NULL) { 627 Node* adr = n->in(MemNode::Address); 628 add_local_var_and_edge(n, PointsToNode::NoEscape, adr, NULL); 629 break; 630 } 631 ELSE_FAIL("Op_LoadP"); 632 } 633 case Op_Phi: { 634 // Using isa_ptr() instead of isa_oopptr() for LoadP and Phi because 635 // ThreadLocal has RawPtr type. 636 const Type* t = n->as_Phi()->type(); 637 if (t->make_ptr() != NULL) { 638 for (uint i = 1; i < n->req(); i++) { 639 Node* in = n->in(i); 640 if (in == NULL) 641 continue; // ignore NULL 642 Node* uncast_in = in->uncast(); 643 if (uncast_in->is_top() || uncast_in == n) 644 continue; // ignore top or inputs which go back this node 645 PointsToNode* ptn = ptnode_adr(in->_idx); 646 assert(ptn != NULL, "node should be registered"); 647 add_edge(n_ptn, ptn); 648 } 649 break; 650 } 651 ELSE_FAIL("Op_Phi"); 652 } 653 case Op_Proj: { 654 // we are only interested in the oop result projection from a call 655 if (n->as_Proj()->_con == TypeFunc::Parms && n->in(0)->is_Call() && 656 n->in(0)->as_Call()->returns_pointer()) { 657 add_local_var_and_edge(n, PointsToNode::NoEscape, n->in(0), NULL); 658 break; 659 } 660 ELSE_FAIL("Op_Proj"); 661 } 662 case Op_Rethrow: // Exception object escapes 663 case Op_Return: { 664 if (n->req() > TypeFunc::Parms && 665 _igvn->type(n->in(TypeFunc::Parms))->isa_oopptr()) { 666 // Treat Return value as LocalVar with GlobalEscape escape state. 667 add_local_var_and_edge(n, PointsToNode::GlobalEscape, 668 n->in(TypeFunc::Parms), NULL); 669 break; 670 } 671 ELSE_FAIL("Op_Return"); 672 } 673 case Op_StoreP: 674 case Op_StoreN: 675 case Op_StoreNKlass: 676 case Op_StorePConditional: 677 case Op_CompareAndSwapP: 678 case Op_CompareAndSwapN: 679 case Op_GetAndSetP: 680 case Op_GetAndSetN: { 681 Node* adr = n->in(MemNode::Address); 682 const Type *adr_type = _igvn->type(adr); 683 adr_type = adr_type->make_ptr(); 684 #ifdef ASSERT 685 if (adr_type == NULL) { 686 n->dump(1); 687 assert(adr_type != NULL, "dead node should not be on list"); 688 break; 689 } 690 #endif 691 if (opcode == Op_GetAndSetP || opcode == Op_GetAndSetN) { 692 add_local_var_and_edge(n, PointsToNode::NoEscape, adr, NULL); 693 } 694 if (adr_type->isa_oopptr() || 695 (opcode == Op_StoreP || opcode == Op_StoreN || opcode == Op_StoreNKlass) && 696 (adr_type == TypeRawPtr::NOTNULL && 697 adr->in(AddPNode::Address)->is_Proj() && 698 adr->in(AddPNode::Address)->in(0)->is_Allocate())) { 699 // Point Address to Value 700 PointsToNode* adr_ptn = ptnode_adr(adr->_idx); 701 assert(adr_ptn != NULL && 702 adr_ptn->as_Field()->is_oop(), "node should be registered"); 703 Node *val = n->in(MemNode::ValueIn); 704 PointsToNode* ptn = ptnode_adr(val->_idx); 705 assert(ptn != NULL, "node should be registered"); 706 add_edge(adr_ptn, ptn); 707 break; 708 } else if ((opcode == Op_StoreP) && (adr_type == TypeRawPtr::BOTTOM)) { 709 // Stored value escapes in unsafe access. 710 Node *val = n->in(MemNode::ValueIn); 711 PointsToNode* ptn = ptnode_adr(val->_idx); 712 assert(ptn != NULL, "node should be registered"); 713 ptn->set_escape_state(PointsToNode::GlobalEscape); 714 // Add edge to object for unsafe access with offset. 715 PointsToNode* adr_ptn = ptnode_adr(adr->_idx); 716 assert(adr_ptn != NULL, "node should be registered"); 717 if (adr_ptn->is_Field()) { 718 assert(adr_ptn->as_Field()->is_oop(), "should be oop field"); 719 add_edge(adr_ptn, ptn); 720 } 721 break; 722 } 723 ELSE_FAIL("Op_StoreP"); 724 } 725 case Op_AryEq: 726 case Op_StrComp: 727 case Op_StrEquals: 728 case Op_StrIndexOf: 729 case Op_EncodeISOArray: { 730 // char[] arrays passed to string intrinsic do not escape but 731 // they are not scalar replaceable. Adjust escape state for them. 732 // Start from in(2) edge since in(1) is memory edge. 733 for (uint i = 2; i < n->req(); i++) { 734 Node* adr = n->in(i); 735 const Type* at = _igvn->type(adr); 736 if (!adr->is_top() && at->isa_ptr()) { 737 assert(at == Type::TOP || at == TypePtr::NULL_PTR || 738 at->isa_ptr() != NULL, "expecting a pointer"); 739 if (adr->is_AddP()) { 740 adr = get_addp_base(adr); 741 } 742 PointsToNode* ptn = ptnode_adr(adr->_idx); 743 assert(ptn != NULL, "node should be registered"); 744 add_edge(n_ptn, ptn); 745 } 746 } 747 break; 748 } 749 default: { 750 // This method should be called only for EA specific nodes which may 751 // miss some edges when they were created. 752 #ifdef ASSERT 753 n->dump(1); 754 #endif 755 guarantee(false, "unknown node"); 756 } 757 } 758 return; 759 } 760 761 void ConnectionGraph::add_call_node(CallNode* call) { 762 assert(call->returns_pointer(), "only for call which returns pointer"); 763 uint call_idx = call->_idx; 764 if (call->is_Allocate()) { 765 Node* k = call->in(AllocateNode::KlassNode); 766 const TypeKlassPtr* kt = k->bottom_type()->isa_klassptr(); 767 assert(kt != NULL, "TypeKlassPtr required."); 768 ciKlass* cik = kt->klass(); 769 PointsToNode::EscapeState es = PointsToNode::NoEscape; 770 bool scalar_replaceable = true; 771 if (call->is_AllocateArray()) { 772 if (!cik->is_array_klass()) { // StressReflectiveCode 773 es = PointsToNode::GlobalEscape; 774 } else { 775 int length = call->in(AllocateNode::ALength)->find_int_con(-1); 776 if (length < 0 || length > EliminateAllocationArraySizeLimit) { 777 // Not scalar replaceable if the length is not constant or too big. 778 scalar_replaceable = false; 779 } 780 } 781 } else { // Allocate instance 782 if (cik->is_subclass_of(_compile->env()->Thread_klass()) || 783 !cik->is_instance_klass() || // StressReflectiveCode 784 cik->as_instance_klass()->has_finalizer()) { 785 es = PointsToNode::GlobalEscape; 786 } 787 } 788 add_java_object(call, es); 789 PointsToNode* ptn = ptnode_adr(call_idx); 790 if (!scalar_replaceable && ptn->scalar_replaceable()) { 791 ptn->set_scalar_replaceable(false); 792 } 793 } else if (call->is_CallStaticJava()) { 794 // Call nodes could be different types: 795 // 796 // 1. CallDynamicJavaNode (what happened during call is unknown): 797 // 798 // - mapped to GlobalEscape JavaObject node if oop is returned; 799 // 800 // - all oop arguments are escaping globally; 801 // 802 // 2. CallStaticJavaNode (execute bytecode analysis if possible): 803 // 804 // - the same as CallDynamicJavaNode if can't do bytecode analysis; 805 // 806 // - mapped to GlobalEscape JavaObject node if unknown oop is returned; 807 // - mapped to NoEscape JavaObject node if non-escaping object allocated 808 // during call is returned; 809 // - mapped to ArgEscape LocalVar node pointed to object arguments 810 // which are returned and does not escape during call; 811 // 812 // - oop arguments escaping status is defined by bytecode analysis; 813 // 814 // For a static call, we know exactly what method is being called. 815 // Use bytecode estimator to record whether the call's return value escapes. 816 ciMethod* meth = call->as_CallJava()->method(); 817 if (meth == NULL) { 818 const char* name = call->as_CallStaticJava()->_name; 819 assert(strncmp(name, "_multianewarray", 15) == 0, "TODO: add failed case check"); 820 // Returns a newly allocated unescaped object. 821 add_java_object(call, PointsToNode::NoEscape); 822 ptnode_adr(call_idx)->set_scalar_replaceable(false); 823 } else if (meth->is_boxing_method()) { 824 // Returns boxing object 825 PointsToNode::EscapeState es; 826 vmIntrinsics::ID intr = meth->intrinsic_id(); 827 if (intr == vmIntrinsics::_floatValue || intr == vmIntrinsics::_doubleValue) { 828 // It does not escape if object is always allocated. 829 es = PointsToNode::NoEscape; 830 } else { 831 // It escapes globally if object could be loaded from cache. 832 es = PointsToNode::GlobalEscape; 833 } 834 add_java_object(call, es); 835 } else { 836 BCEscapeAnalyzer* call_analyzer = meth->get_bcea(); 837 call_analyzer->copy_dependencies(_compile->dependencies()); 838 if (call_analyzer->is_return_allocated()) { 839 // Returns a newly allocated unescaped object, simply 840 // update dependency information. 841 // Mark it as NoEscape so that objects referenced by 842 // it's fields will be marked as NoEscape at least. 843 add_java_object(call, PointsToNode::NoEscape); 844 ptnode_adr(call_idx)->set_scalar_replaceable(false); 845 } else { 846 // Determine whether any arguments are returned. 847 const TypeTuple* d = call->tf()->domain(); 848 bool ret_arg = false; 849 for (uint i = TypeFunc::Parms; i < d->cnt(); i++) { 850 if (d->field_at(i)->isa_ptr() != NULL && 851 call_analyzer->is_arg_returned(i - TypeFunc::Parms)) { 852 ret_arg = true; 853 break; 854 } 855 } 856 if (ret_arg) { 857 add_local_var(call, PointsToNode::ArgEscape); 858 } else { 859 // Returns unknown object. 860 map_ideal_node(call, phantom_obj); 861 } 862 } 863 } 864 } else { 865 // An other type of call, assume the worst case: 866 // returned value is unknown and globally escapes. 867 assert(call->Opcode() == Op_CallDynamicJava, "add failed case check"); 868 map_ideal_node(call, phantom_obj); 869 } 870 } 871 872 void ConnectionGraph::process_call_arguments(CallNode *call) { 873 bool is_arraycopy = false; 874 switch (call->Opcode()) { 875 #ifdef ASSERT 876 case Op_Allocate: 877 case Op_AllocateArray: 878 case Op_Lock: 879 case Op_Unlock: 880 assert(false, "should be done already"); 881 break; 882 #endif 883 case Op_CallLeafNoFP: 884 is_arraycopy = (call->as_CallLeaf()->_name != NULL && 885 strstr(call->as_CallLeaf()->_name, "arraycopy") != 0); 886 // fall through 887 case Op_CallLeaf: { 888 // Stub calls, objects do not escape but they are not scale replaceable. 889 // Adjust escape state for outgoing arguments. 890 const TypeTuple * d = call->tf()->domain(); 891 bool src_has_oops = false; 892 for (uint i = TypeFunc::Parms; i < d->cnt(); i++) { 893 const Type* at = d->field_at(i); 894 Node *arg = call->in(i); 895 const Type *aat = _igvn->type(arg); 896 if (arg->is_top() || !at->isa_ptr() || !aat->isa_ptr()) 897 continue; 898 if (arg->is_AddP()) { 899 // 900 // The inline_native_clone() case when the arraycopy stub is called 901 // after the allocation before Initialize and CheckCastPP nodes. 902 // Or normal arraycopy for object arrays case. 903 // 904 // Set AddP's base (Allocate) as not scalar replaceable since 905 // pointer to the base (with offset) is passed as argument. 906 // 907 arg = get_addp_base(arg); 908 } 909 PointsToNode* arg_ptn = ptnode_adr(arg->_idx); 910 assert(arg_ptn != NULL, "should be registered"); 911 PointsToNode::EscapeState arg_esc = arg_ptn->escape_state(); 912 if (is_arraycopy || arg_esc < PointsToNode::ArgEscape) { 913 assert(aat == Type::TOP || aat == TypePtr::NULL_PTR || 914 aat->isa_ptr() != NULL, "expecting an Ptr"); 915 bool arg_has_oops = aat->isa_oopptr() && 916 (aat->isa_oopptr()->klass() == NULL || aat->isa_instptr() || 917 (aat->isa_aryptr() && aat->isa_aryptr()->klass()->is_obj_array_klass())); 918 if (i == TypeFunc::Parms) { 919 src_has_oops = arg_has_oops; 920 } 921 // 922 // src or dst could be j.l.Object when other is basic type array: 923 // 924 // arraycopy(char[],0,Object*,0,size); 925 // arraycopy(Object*,0,char[],0,size); 926 // 927 // Don't add edges in such cases. 928 // 929 bool arg_is_arraycopy_dest = src_has_oops && is_arraycopy && 930 arg_has_oops && (i > TypeFunc::Parms); 931 #ifdef ASSERT 932 if (!(is_arraycopy || 933 (call->as_CallLeaf()->_name != NULL && 934 (strcmp(call->as_CallLeaf()->_name, "g1_wb_pre") == 0 || 935 strcmp(call->as_CallLeaf()->_name, "g1_wb_post") == 0 || 936 strcmp(call->as_CallLeaf()->_name, "aescrypt_encryptBlock") == 0 || 937 strcmp(call->as_CallLeaf()->_name, "aescrypt_decryptBlock") == 0 || 938 strcmp(call->as_CallLeaf()->_name, "cipherBlockChaining_encryptAESCrypt") == 0 || 939 strcmp(call->as_CallLeaf()->_name, "cipherBlockChaining_decryptAESCrypt") == 0) 940 ))) { 941 call->dump(); 942 fatal(err_msg_res("EA unexpected CallLeaf %s", call->as_CallLeaf()->_name)); 943 } 944 #endif 945 // Always process arraycopy's destination object since 946 // we need to add all possible edges to references in 947 // source object. 948 if (arg_esc >= PointsToNode::ArgEscape && 949 !arg_is_arraycopy_dest) { 950 continue; 951 } 952 set_escape_state(arg_ptn, PointsToNode::ArgEscape); 953 if (arg_is_arraycopy_dest) { 954 Node* src = call->in(TypeFunc::Parms); 955 if (src->is_AddP()) { 956 src = get_addp_base(src); 957 } 958 PointsToNode* src_ptn = ptnode_adr(src->_idx); 959 assert(src_ptn != NULL, "should be registered"); 960 if (arg_ptn != src_ptn) { 961 // Special arraycopy edge: 962 // A destination object's field can't have the source object 963 // as base since objects escape states are not related. 964 // Only escape state of destination object's fields affects 965 // escape state of fields in source object. 966 add_arraycopy(call, PointsToNode::ArgEscape, src_ptn, arg_ptn); 967 } 968 } 969 } 970 } 971 break; 972 } 973 case Op_CallStaticJava: { 974 // For a static call, we know exactly what method is being called. 975 // Use bytecode estimator to record the call's escape affects 976 #ifdef ASSERT 977 const char* name = call->as_CallStaticJava()->_name; 978 assert((name == NULL || strcmp(name, "uncommon_trap") != 0), "normal calls only"); 979 #endif 980 ciMethod* meth = call->as_CallJava()->method(); 981 if ((meth != NULL) && meth->is_boxing_method()) { 982 break; // Boxing methods do not modify any oops. 983 } 984 BCEscapeAnalyzer* call_analyzer = (meth !=NULL) ? meth->get_bcea() : NULL; 985 // fall-through if not a Java method or no analyzer information 986 if (call_analyzer != NULL) { 987 PointsToNode* call_ptn = ptnode_adr(call->_idx); 988 const TypeTuple* d = call->tf()->domain(); 989 for (uint i = TypeFunc::Parms; i < d->cnt(); i++) { 990 const Type* at = d->field_at(i); 991 int k = i - TypeFunc::Parms; 992 Node* arg = call->in(i); 993 PointsToNode* arg_ptn = ptnode_adr(arg->_idx); 994 if (at->isa_ptr() != NULL && 995 call_analyzer->is_arg_returned(k)) { 996 // The call returns arguments. 997 if (call_ptn != NULL) { // Is call's result used? 998 assert(call_ptn->is_LocalVar(), "node should be registered"); 999 assert(arg_ptn != NULL, "node should be registered"); 1000 add_edge(call_ptn, arg_ptn); 1001 } 1002 } 1003 if (at->isa_oopptr() != NULL && 1004 arg_ptn->escape_state() < PointsToNode::GlobalEscape) { 1005 if (!call_analyzer->is_arg_stack(k)) { 1006 // The argument global escapes 1007 set_escape_state(arg_ptn, PointsToNode::GlobalEscape); 1008 } else { 1009 set_escape_state(arg_ptn, PointsToNode::ArgEscape); 1010 if (!call_analyzer->is_arg_local(k)) { 1011 // The argument itself doesn't escape, but any fields might 1012 set_fields_escape_state(arg_ptn, PointsToNode::GlobalEscape); 1013 } 1014 } 1015 } 1016 } 1017 if (call_ptn != NULL && call_ptn->is_LocalVar()) { 1018 // The call returns arguments. 1019 assert(call_ptn->edge_count() > 0, "sanity"); 1020 if (!call_analyzer->is_return_local()) { 1021 // Returns also unknown object. 1022 add_edge(call_ptn, phantom_obj); 1023 } 1024 } 1025 break; 1026 } 1027 } 1028 default: { 1029 // Fall-through here if not a Java method or no analyzer information 1030 // or some other type of call, assume the worst case: all arguments 1031 // globally escape. 1032 const TypeTuple* d = call->tf()->domain(); 1033 for (uint i = TypeFunc::Parms; i < d->cnt(); i++) { 1034 const Type* at = d->field_at(i); 1035 if (at->isa_oopptr() != NULL) { 1036 Node* arg = call->in(i); 1037 if (arg->is_AddP()) { 1038 arg = get_addp_base(arg); 1039 } 1040 assert(ptnode_adr(arg->_idx) != NULL, "should be defined already"); 1041 set_escape_state(ptnode_adr(arg->_idx), PointsToNode::GlobalEscape); 1042 } 1043 } 1044 } 1045 } 1046 } 1047 1048 1049 // Finish Graph construction. 1050 bool ConnectionGraph::complete_connection_graph( 1051 GrowableArray<PointsToNode*>& ptnodes_worklist, 1052 GrowableArray<JavaObjectNode*>& non_escaped_worklist, 1053 GrowableArray<JavaObjectNode*>& java_objects_worklist, 1054 GrowableArray<FieldNode*>& oop_fields_worklist) { 1055 // Normally only 1-3 passes needed to build Connection Graph depending 1056 // on graph complexity. Observed 8 passes in jvm2008 compiler.compiler. 1057 // Set limit to 20 to catch situation when something did go wrong and 1058 // bailout Escape Analysis. 1059 // Also limit build time to 30 sec (60 in debug VM). 1060 #define CG_BUILD_ITER_LIMIT 20 1061 #ifdef ASSERT 1062 #define CG_BUILD_TIME_LIMIT 60.0 1063 #else 1064 #define CG_BUILD_TIME_LIMIT 30.0 1065 #endif 1066 1067 // Propagate GlobalEscape and ArgEscape escape states and check that 1068 // we still have non-escaping objects. The method pushs on _worklist 1069 // Field nodes which reference phantom_object. 1070 if (!find_non_escaped_objects(ptnodes_worklist, non_escaped_worklist)) { 1071 return false; // Nothing to do. 1072 } 1073 // Now propagate references to all JavaObject nodes. 1074 int java_objects_length = java_objects_worklist.length(); 1075 elapsedTimer time; 1076 int new_edges = 1; 1077 int iterations = 0; 1078 do { 1079 while ((new_edges > 0) && 1080 (iterations++ < CG_BUILD_ITER_LIMIT) && 1081 (time.seconds() < CG_BUILD_TIME_LIMIT)) { 1082 time.start(); 1083 new_edges = 0; 1084 // Propagate references to phantom_object for nodes pushed on _worklist 1085 // by find_non_escaped_objects() and find_field_value(). 1086 new_edges += add_java_object_edges(phantom_obj, false); 1087 for (int next = 0; next < java_objects_length; ++next) { 1088 JavaObjectNode* ptn = java_objects_worklist.at(next); 1089 new_edges += add_java_object_edges(ptn, true); 1090 } 1091 if (new_edges > 0) { 1092 // Update escape states on each iteration if graph was updated. 1093 if (!find_non_escaped_objects(ptnodes_worklist, non_escaped_worklist)) { 1094 return false; // Nothing to do. 1095 } 1096 } 1097 time.stop(); 1098 } 1099 if ((iterations < CG_BUILD_ITER_LIMIT) && 1100 (time.seconds() < CG_BUILD_TIME_LIMIT)) { 1101 time.start(); 1102 // Find fields which have unknown value. 1103 int fields_length = oop_fields_worklist.length(); 1104 for (int next = 0; next < fields_length; next++) { 1105 FieldNode* field = oop_fields_worklist.at(next); 1106 if (field->edge_count() == 0) { 1107 new_edges += find_field_value(field); 1108 // This code may added new edges to phantom_object. 1109 // Need an other cycle to propagate references to phantom_object. 1110 } 1111 } 1112 time.stop(); 1113 } else { 1114 new_edges = 0; // Bailout 1115 } 1116 } while (new_edges > 0); 1117 1118 // Bailout if passed limits. 1119 if ((iterations >= CG_BUILD_ITER_LIMIT) || 1120 (time.seconds() >= CG_BUILD_TIME_LIMIT)) { 1121 Compile* C = _compile; 1122 if (C->log() != NULL) { 1123 C->log()->begin_elem("connectionGraph_bailout reason='reached "); 1124 C->log()->text("%s", (iterations >= CG_BUILD_ITER_LIMIT) ? "iterations" : "time"); 1125 C->log()->end_elem(" limit'"); 1126 } 1127 assert(ExitEscapeAnalysisOnTimeout, err_msg_res("infinite EA connection graph build (%f sec, %d iterations) with %d nodes and worklist size %d", 1128 time.seconds(), iterations, nodes_size(), ptnodes_worklist.length())); 1129 // Possible infinite build_connection_graph loop, 1130 // bailout (no changes to ideal graph were made). 1131 return false; 1132 } 1133 #ifdef ASSERT 1134 if (Verbose && PrintEscapeAnalysis) { 1135 tty->print_cr("EA: %d iterations to build connection graph with %d nodes and worklist size %d", 1136 iterations, nodes_size(), ptnodes_worklist.length()); 1137 } 1138 #endif 1139 1140 #undef CG_BUILD_ITER_LIMIT 1141 #undef CG_BUILD_TIME_LIMIT 1142 1143 // Find fields initialized by NULL for non-escaping Allocations. 1144 int non_escaped_length = non_escaped_worklist.length(); 1145 for (int next = 0; next < non_escaped_length; next++) { 1146 JavaObjectNode* ptn = non_escaped_worklist.at(next); 1147 PointsToNode::EscapeState es = ptn->escape_state(); 1148 assert(es <= PointsToNode::ArgEscape, "sanity"); 1149 if (es == PointsToNode::NoEscape) { 1150 if (find_init_values(ptn, null_obj, _igvn) > 0) { 1151 // Adding references to NULL object does not change escape states 1152 // since it does not escape. Also no fields are added to NULL object. 1153 add_java_object_edges(null_obj, false); 1154 } 1155 } 1156 Node* n = ptn->ideal_node(); 1157 if (n->is_Allocate()) { 1158 // The object allocated by this Allocate node will never be 1159 // seen by an other thread. Mark it so that when it is 1160 // expanded no MemBarStoreStore is added. 1161 InitializeNode* ini = n->as_Allocate()->initialization(); 1162 if (ini != NULL) 1163 ini->set_does_not_escape(); 1164 } 1165 } 1166 return true; // Finished graph construction. 1167 } 1168 1169 // Propagate GlobalEscape and ArgEscape escape states to all nodes 1170 // and check that we still have non-escaping java objects. 1171 bool ConnectionGraph::find_non_escaped_objects(GrowableArray<PointsToNode*>& ptnodes_worklist, 1172 GrowableArray<JavaObjectNode*>& non_escaped_worklist) { 1173 GrowableArray<PointsToNode*> escape_worklist; 1174 // First, put all nodes with GlobalEscape and ArgEscape states on worklist. 1175 int ptnodes_length = ptnodes_worklist.length(); 1176 for (int next = 0; next < ptnodes_length; ++next) { 1177 PointsToNode* ptn = ptnodes_worklist.at(next); 1178 if (ptn->escape_state() >= PointsToNode::ArgEscape || 1179 ptn->fields_escape_state() >= PointsToNode::ArgEscape) { 1180 escape_worklist.push(ptn); 1181 } 1182 } 1183 // Set escape states to referenced nodes (edges list). 1184 while (escape_worklist.length() > 0) { 1185 PointsToNode* ptn = escape_worklist.pop(); 1186 PointsToNode::EscapeState es = ptn->escape_state(); 1187 PointsToNode::EscapeState field_es = ptn->fields_escape_state(); 1188 if (ptn->is_Field() && ptn->as_Field()->is_oop() && 1189 es >= PointsToNode::ArgEscape) { 1190 // GlobalEscape or ArgEscape state of field means it has unknown value. 1191 if (add_edge(ptn, phantom_obj)) { 1192 // New edge was added 1193 add_field_uses_to_worklist(ptn->as_Field()); 1194 } 1195 } 1196 for (EdgeIterator i(ptn); i.has_next(); i.next()) { 1197 PointsToNode* e = i.get(); 1198 if (e->is_Arraycopy()) { 1199 assert(ptn->arraycopy_dst(), "sanity"); 1200 // Propagate only fields escape state through arraycopy edge. 1201 if (e->fields_escape_state() < field_es) { 1202 set_fields_escape_state(e, field_es); 1203 escape_worklist.push(e); 1204 } 1205 } else if (es >= field_es) { 1206 // fields_escape_state is also set to 'es' if it is less than 'es'. 1207 if (e->escape_state() < es) { 1208 set_escape_state(e, es); 1209 escape_worklist.push(e); 1210 } 1211 } else { 1212 // Propagate field escape state. 1213 bool es_changed = false; 1214 if (e->fields_escape_state() < field_es) { 1215 set_fields_escape_state(e, field_es); 1216 es_changed = true; 1217 } 1218 if ((e->escape_state() < field_es) && 1219 e->is_Field() && ptn->is_JavaObject() && 1220 e->as_Field()->is_oop()) { 1221 // Change escape state of referenced fileds. 1222 set_escape_state(e, field_es); 1223 es_changed = true;; 1224 } else if (e->escape_state() < es) { 1225 set_escape_state(e, es); 1226 es_changed = true;; 1227 } 1228 if (es_changed) { 1229 escape_worklist.push(e); 1230 } 1231 } 1232 } 1233 } 1234 // Remove escaped objects from non_escaped list. 1235 for (int next = non_escaped_worklist.length()-1; next >= 0 ; --next) { 1236 JavaObjectNode* ptn = non_escaped_worklist.at(next); 1237 if (ptn->escape_state() >= PointsToNode::GlobalEscape) { 1238 non_escaped_worklist.delete_at(next); 1239 } 1240 if (ptn->escape_state() == PointsToNode::NoEscape) { 1241 // Find fields in non-escaped allocations which have unknown value. 1242 find_init_values(ptn, phantom_obj, NULL); 1243 } 1244 } 1245 return (non_escaped_worklist.length() > 0); 1246 } 1247 1248 // Add all references to JavaObject node by walking over all uses. 1249 int ConnectionGraph::add_java_object_edges(JavaObjectNode* jobj, bool populate_worklist) { 1250 int new_edges = 0; 1251 if (populate_worklist) { 1252 // Populate _worklist by uses of jobj's uses. 1253 for (UseIterator i(jobj); i.has_next(); i.next()) { 1254 PointsToNode* use = i.get(); 1255 if (use->is_Arraycopy()) 1256 continue; 1257 add_uses_to_worklist(use); 1258 if (use->is_Field() && use->as_Field()->is_oop()) { 1259 // Put on worklist all field's uses (loads) and 1260 // related field nodes (same base and offset). 1261 add_field_uses_to_worklist(use->as_Field()); 1262 } 1263 } 1264 } 1265 while(_worklist.length() > 0) { 1266 PointsToNode* use = _worklist.pop(); 1267 if (PointsToNode::is_base_use(use)) { 1268 // Add reference from jobj to field and from field to jobj (field's base). 1269 use = PointsToNode::get_use_node(use)->as_Field(); 1270 if (add_base(use->as_Field(), jobj)) { 1271 new_edges++; 1272 } 1273 continue; 1274 } 1275 assert(!use->is_JavaObject(), "sanity"); 1276 if (use->is_Arraycopy()) { 1277 if (jobj == null_obj) // NULL object does not have field edges 1278 continue; 1279 // Added edge from Arraycopy node to arraycopy's source java object 1280 if (add_edge(use, jobj)) { 1281 jobj->set_arraycopy_src(); 1282 new_edges++; 1283 } 1284 // and stop here. 1285 continue; 1286 } 1287 if (!add_edge(use, jobj)) 1288 continue; // No new edge added, there was such edge already. 1289 new_edges++; 1290 if (use->is_LocalVar()) { 1291 add_uses_to_worklist(use); 1292 if (use->arraycopy_dst()) { 1293 for (EdgeIterator i(use); i.has_next(); i.next()) { 1294 PointsToNode* e = i.get(); 1295 if (e->is_Arraycopy()) { 1296 if (jobj == null_obj) // NULL object does not have field edges 1297 continue; 1298 // Add edge from arraycopy's destination java object to Arraycopy node. 1299 if (add_edge(jobj, e)) { 1300 new_edges++; 1301 jobj->set_arraycopy_dst(); 1302 } 1303 } 1304 } 1305 } 1306 } else { 1307 // Added new edge to stored in field values. 1308 // Put on worklist all field's uses (loads) and 1309 // related field nodes (same base and offset). 1310 add_field_uses_to_worklist(use->as_Field()); 1311 } 1312 } 1313 return new_edges; 1314 } 1315 1316 // Put on worklist all related field nodes. 1317 void ConnectionGraph::add_field_uses_to_worklist(FieldNode* field) { 1318 assert(field->is_oop(), "sanity"); 1319 int offset = field->offset(); 1320 add_uses_to_worklist(field); 1321 // Loop over all bases of this field and push on worklist Field nodes 1322 // with the same offset and base (since they may reference the same field). 1323 for (BaseIterator i(field); i.has_next(); i.next()) { 1324 PointsToNode* base = i.get(); 1325 add_fields_to_worklist(field, base); 1326 // Check if the base was source object of arraycopy and go over arraycopy's 1327 // destination objects since values stored to a field of source object are 1328 // accessable by uses (loads) of fields of destination objects. 1329 if (base->arraycopy_src()) { 1330 for (UseIterator j(base); j.has_next(); j.next()) { 1331 PointsToNode* arycp = j.get(); 1332 if (arycp->is_Arraycopy()) { 1333 for (UseIterator k(arycp); k.has_next(); k.next()) { 1334 PointsToNode* abase = k.get(); 1335 if (abase->arraycopy_dst() && abase != base) { 1336 // Look for the same arracopy reference. 1337 add_fields_to_worklist(field, abase); 1338 } 1339 } 1340 } 1341 } 1342 } 1343 } 1344 } 1345 1346 // Put on worklist all related field nodes. 1347 void ConnectionGraph::add_fields_to_worklist(FieldNode* field, PointsToNode* base) { 1348 int offset = field->offset(); 1349 if (base->is_LocalVar()) { 1350 for (UseIterator j(base); j.has_next(); j.next()) { 1351 PointsToNode* f = j.get(); 1352 if (PointsToNode::is_base_use(f)) { // Field 1353 f = PointsToNode::get_use_node(f); 1354 if (f == field || !f->as_Field()->is_oop()) 1355 continue; 1356 int offs = f->as_Field()->offset(); 1357 if (offs == offset || offset == Type::OffsetBot || offs == Type::OffsetBot) { 1358 add_to_worklist(f); 1359 } 1360 } 1361 } 1362 } else { 1363 assert(base->is_JavaObject(), "sanity"); 1364 if (// Skip phantom_object since it is only used to indicate that 1365 // this field's content globally escapes. 1366 (base != phantom_obj) && 1367 // NULL object node does not have fields. 1368 (base != null_obj)) { 1369 for (EdgeIterator i(base); i.has_next(); i.next()) { 1370 PointsToNode* f = i.get(); 1371 // Skip arraycopy edge since store to destination object field 1372 // does not update value in source object field. 1373 if (f->is_Arraycopy()) { 1374 assert(base->arraycopy_dst(), "sanity"); 1375 continue; 1376 } 1377 if (f == field || !f->as_Field()->is_oop()) 1378 continue; 1379 int offs = f->as_Field()->offset(); 1380 if (offs == offset || offset == Type::OffsetBot || offs == Type::OffsetBot) { 1381 add_to_worklist(f); 1382 } 1383 } 1384 } 1385 } 1386 } 1387 1388 // Find fields which have unknown value. 1389 int ConnectionGraph::find_field_value(FieldNode* field) { 1390 // Escaped fields should have init value already. 1391 assert(field->escape_state() == PointsToNode::NoEscape, "sanity"); 1392 int new_edges = 0; 1393 for (BaseIterator i(field); i.has_next(); i.next()) { 1394 PointsToNode* base = i.get(); 1395 if (base->is_JavaObject()) { 1396 // Skip Allocate's fields which will be processed later. 1397 if (base->ideal_node()->is_Allocate()) 1398 return 0; 1399 assert(base == null_obj, "only NULL ptr base expected here"); 1400 } 1401 } 1402 if (add_edge(field, phantom_obj)) { 1403 // New edge was added 1404 new_edges++; 1405 add_field_uses_to_worklist(field); 1406 } 1407 return new_edges; 1408 } 1409 1410 // Find fields initializing values for allocations. 1411 int ConnectionGraph::find_init_values(JavaObjectNode* pta, PointsToNode* init_val, PhaseTransform* phase) { 1412 assert(pta->escape_state() == PointsToNode::NoEscape, "Not escaped Allocate nodes only"); 1413 int new_edges = 0; 1414 Node* alloc = pta->ideal_node(); 1415 if (init_val == phantom_obj) { 1416 // Do nothing for Allocate nodes since its fields values are "known". 1417 if (alloc->is_Allocate()) 1418 return 0; 1419 assert(alloc->as_CallStaticJava(), "sanity"); 1420 #ifdef ASSERT 1421 if (alloc->as_CallStaticJava()->method() == NULL) { 1422 const char* name = alloc->as_CallStaticJava()->_name; 1423 assert(strncmp(name, "_multianewarray", 15) == 0, "sanity"); 1424 } 1425 #endif 1426 // Non-escaped allocation returned from Java or runtime call have 1427 // unknown values in fields. 1428 for (EdgeIterator i(pta); i.has_next(); i.next()) { 1429 PointsToNode* field = i.get(); 1430 if (field->is_Field() && field->as_Field()->is_oop()) { 1431 if (add_edge(field, phantom_obj)) { 1432 // New edge was added 1433 new_edges++; 1434 add_field_uses_to_worklist(field->as_Field()); 1435 } 1436 } 1437 } 1438 return new_edges; 1439 } 1440 assert(init_val == null_obj, "sanity"); 1441 // Do nothing for Call nodes since its fields values are unknown. 1442 if (!alloc->is_Allocate()) 1443 return 0; 1444 1445 InitializeNode* ini = alloc->as_Allocate()->initialization(); 1446 Compile* C = _compile; 1447 bool visited_bottom_offset = false; 1448 GrowableArray<int> offsets_worklist; 1449 1450 // Check if an oop field's initializing value is recorded and add 1451 // a corresponding NULL if field's value if it is not recorded. 1452 // Connection Graph does not record a default initialization by NULL 1453 // captured by Initialize node. 1454 // 1455 for (EdgeIterator i(pta); i.has_next(); i.next()) { 1456 PointsToNode* field = i.get(); // Field (AddP) 1457 if (!field->is_Field() || !field->as_Field()->is_oop()) 1458 continue; // Not oop field 1459 int offset = field->as_Field()->offset(); 1460 if (offset == Type::OffsetBot) { 1461 if (!visited_bottom_offset) { 1462 // OffsetBot is used to reference array's element, 1463 // always add reference to NULL to all Field nodes since we don't 1464 // known which element is referenced. 1465 if (add_edge(field, null_obj)) { 1466 // New edge was added 1467 new_edges++; 1468 add_field_uses_to_worklist(field->as_Field()); 1469 visited_bottom_offset = true; 1470 } 1471 } 1472 } else { 1473 // Check only oop fields. 1474 const Type* adr_type = field->ideal_node()->as_AddP()->bottom_type(); 1475 if (adr_type->isa_rawptr()) { 1476 #ifdef ASSERT 1477 // Raw pointers are used for initializing stores so skip it 1478 // since it should be recorded already 1479 Node* base = get_addp_base(field->ideal_node()); 1480 assert(adr_type->isa_rawptr() && base->is_Proj() && 1481 (base->in(0) == alloc),"unexpected pointer type"); 1482 #endif 1483 continue; 1484 } 1485 if (!offsets_worklist.contains(offset)) { 1486 offsets_worklist.append(offset); 1487 Node* value = NULL; 1488 if (ini != NULL) { 1489 // StoreP::memory_type() == T_ADDRESS 1490 BasicType ft = UseCompressedOops ? T_NARROWOOP : T_ADDRESS; 1491 Node* store = ini->find_captured_store(offset, type2aelembytes(ft, true), phase); 1492 // Make sure initializing store has the same type as this AddP. 1493 // This AddP may reference non existing field because it is on a 1494 // dead branch of bimorphic call which is not eliminated yet. 1495 if (store != NULL && store->is_Store() && 1496 store->as_Store()->memory_type() == ft) { 1497 value = store->in(MemNode::ValueIn); 1498 #ifdef ASSERT 1499 if (VerifyConnectionGraph) { 1500 // Verify that AddP already points to all objects the value points to. 1501 PointsToNode* val = ptnode_adr(value->_idx); 1502 assert((val != NULL), "should be processed already"); 1503 PointsToNode* missed_obj = NULL; 1504 if (val->is_JavaObject()) { 1505 if (!field->points_to(val->as_JavaObject())) { 1506 missed_obj = val; 1507 } 1508 } else { 1509 if (!val->is_LocalVar() || (val->edge_count() == 0)) { 1510 tty->print_cr("----------init store has invalid value -----"); 1511 store->dump(); 1512 val->dump(); 1513 assert(val->is_LocalVar() && (val->edge_count() > 0), "should be processed already"); 1514 } 1515 for (EdgeIterator j(val); j.has_next(); j.next()) { 1516 PointsToNode* obj = j.get(); 1517 if (obj->is_JavaObject()) { 1518 if (!field->points_to(obj->as_JavaObject())) { 1519 missed_obj = obj; 1520 break; 1521 } 1522 } 1523 } 1524 } 1525 if (missed_obj != NULL) { 1526 tty->print_cr("----------field---------------------------------"); 1527 field->dump(); 1528 tty->print_cr("----------missed referernce to object-----------"); 1529 missed_obj->dump(); 1530 tty->print_cr("----------object referernced by init store -----"); 1531 store->dump(); 1532 val->dump(); 1533 assert(!field->points_to(missed_obj->as_JavaObject()), "missed JavaObject reference"); 1534 } 1535 } 1536 #endif 1537 } else { 1538 // There could be initializing stores which follow allocation. 1539 // For example, a volatile field store is not collected 1540 // by Initialize node. 1541 // 1542 // Need to check for dependent loads to separate such stores from 1543 // stores which follow loads. For now, add initial value NULL so 1544 // that compare pointers optimization works correctly. 1545 } 1546 } 1547 if (value == NULL) { 1548 // A field's initializing value was not recorded. Add NULL. 1549 if (add_edge(field, null_obj)) { 1550 // New edge was added 1551 new_edges++; 1552 add_field_uses_to_worklist(field->as_Field()); 1553 } 1554 } 1555 } 1556 } 1557 } 1558 return new_edges; 1559 } 1560 1561 // Adjust scalar_replaceable state after Connection Graph is built. 1562 void ConnectionGraph::adjust_scalar_replaceable_state(JavaObjectNode* jobj) { 1563 // Search for non-escaping objects which are not scalar replaceable 1564 // and mark them to propagate the state to referenced objects. 1565 1566 // 1. An object is not scalar replaceable if the field into which it is 1567 // stored has unknown offset (stored into unknown element of an array). 1568 // 1569 for (UseIterator i(jobj); i.has_next(); i.next()) { 1570 PointsToNode* use = i.get(); 1571 assert(!use->is_Arraycopy(), "sanity"); 1572 if (use->is_Field()) { 1573 FieldNode* field = use->as_Field(); 1574 assert(field->is_oop() && field->scalar_replaceable() && 1575 field->fields_escape_state() == PointsToNode::NoEscape, "sanity"); 1576 if (field->offset() == Type::OffsetBot) { 1577 jobj->set_scalar_replaceable(false); 1578 return; 1579 } 1580 } 1581 assert(use->is_Field() || use->is_LocalVar(), "sanity"); 1582 // 2. An object is not scalar replaceable if it is merged with other objects. 1583 for (EdgeIterator j(use); j.has_next(); j.next()) { 1584 PointsToNode* ptn = j.get(); 1585 if (ptn->is_JavaObject() && ptn != jobj) { 1586 // Mark all objects. 1587 jobj->set_scalar_replaceable(false); 1588 ptn->set_scalar_replaceable(false); 1589 } 1590 } 1591 if (!jobj->scalar_replaceable()) { 1592 return; 1593 } 1594 } 1595 1596 for (EdgeIterator j(jobj); j.has_next(); j.next()) { 1597 // Non-escaping object node should point only to field nodes. 1598 FieldNode* field = j.get()->as_Field(); 1599 int offset = field->as_Field()->offset(); 1600 1601 // 3. An object is not scalar replaceable if it has a field with unknown 1602 // offset (array's element is accessed in loop). 1603 if (offset == Type::OffsetBot) { 1604 jobj->set_scalar_replaceable(false); 1605 return; 1606 } 1607 // 4. Currently an object is not scalar replaceable if a LoadStore node 1608 // access its field since the field value is unknown after it. 1609 // 1610 Node* n = field->ideal_node(); 1611 for (DUIterator_Fast imax, i = n->fast_outs(imax); i < imax; i++) { 1612 if (n->fast_out(i)->is_LoadStore()) { 1613 jobj->set_scalar_replaceable(false); 1614 return; 1615 } 1616 } 1617 1618 // 5. Or the address may point to more then one object. This may produce 1619 // the false positive result (set not scalar replaceable) 1620 // since the flow-insensitive escape analysis can't separate 1621 // the case when stores overwrite the field's value from the case 1622 // when stores happened on different control branches. 1623 // 1624 // Note: it will disable scalar replacement in some cases: 1625 // 1626 // Point p[] = new Point[1]; 1627 // p[0] = new Point(); // Will be not scalar replaced 1628 // 1629 // but it will save us from incorrect optimizations in next cases: 1630 // 1631 // Point p[] = new Point[1]; 1632 // if ( x ) p[0] = new Point(); // Will be not scalar replaced 1633 // 1634 if (field->base_count() > 1) { 1635 for (BaseIterator i(field); i.has_next(); i.next()) { 1636 PointsToNode* base = i.get(); 1637 // Don't take into account LocalVar nodes which 1638 // may point to only one object which should be also 1639 // this field's base by now. 1640 if (base->is_JavaObject() && base != jobj) { 1641 // Mark all bases. 1642 jobj->set_scalar_replaceable(false); 1643 base->set_scalar_replaceable(false); 1644 } 1645 } 1646 } 1647 } 1648 } 1649 1650 #ifdef ASSERT 1651 void ConnectionGraph::verify_connection_graph( 1652 GrowableArray<PointsToNode*>& ptnodes_worklist, 1653 GrowableArray<JavaObjectNode*>& non_escaped_worklist, 1654 GrowableArray<JavaObjectNode*>& java_objects_worklist, 1655 GrowableArray<Node*>& addp_worklist) { 1656 // Verify that graph is complete - no new edges could be added. 1657 int java_objects_length = java_objects_worklist.length(); 1658 int non_escaped_length = non_escaped_worklist.length(); 1659 int new_edges = 0; 1660 for (int next = 0; next < java_objects_length; ++next) { 1661 JavaObjectNode* ptn = java_objects_worklist.at(next); 1662 new_edges += add_java_object_edges(ptn, true); 1663 } 1664 assert(new_edges == 0, "graph was not complete"); 1665 // Verify that escape state is final. 1666 int length = non_escaped_worklist.length(); 1667 find_non_escaped_objects(ptnodes_worklist, non_escaped_worklist); 1668 assert((non_escaped_length == non_escaped_worklist.length()) && 1669 (non_escaped_length == length) && 1670 (_worklist.length() == 0), "escape state was not final"); 1671 1672 // Verify fields information. 1673 int addp_length = addp_worklist.length(); 1674 for (int next = 0; next < addp_length; ++next ) { 1675 Node* n = addp_worklist.at(next); 1676 FieldNode* field = ptnode_adr(n->_idx)->as_Field(); 1677 if (field->is_oop()) { 1678 // Verify that field has all bases 1679 Node* base = get_addp_base(n); 1680 PointsToNode* ptn = ptnode_adr(base->_idx); 1681 if (ptn->is_JavaObject()) { 1682 assert(field->has_base(ptn->as_JavaObject()), "sanity"); 1683 } else { 1684 assert(ptn->is_LocalVar(), "sanity"); 1685 for (EdgeIterator i(ptn); i.has_next(); i.next()) { 1686 PointsToNode* e = i.get(); 1687 if (e->is_JavaObject()) { 1688 assert(field->has_base(e->as_JavaObject()), "sanity"); 1689 } 1690 } 1691 } 1692 // Verify that all fields have initializing values. 1693 if (field->edge_count() == 0) { 1694 tty->print_cr("----------field does not have references----------"); 1695 field->dump(); 1696 for (BaseIterator i(field); i.has_next(); i.next()) { 1697 PointsToNode* base = i.get(); 1698 tty->print_cr("----------field has next base---------------------"); 1699 base->dump(); 1700 if (base->is_JavaObject() && (base != phantom_obj) && (base != null_obj)) { 1701 tty->print_cr("----------base has fields-------------------------"); 1702 for (EdgeIterator j(base); j.has_next(); j.next()) { 1703 j.get()->dump(); 1704 } 1705 tty->print_cr("----------base has references---------------------"); 1706 for (UseIterator j(base); j.has_next(); j.next()) { 1707 j.get()->dump(); 1708 } 1709 } 1710 } 1711 for (UseIterator i(field); i.has_next(); i.next()) { 1712 i.get()->dump(); 1713 } 1714 assert(field->edge_count() > 0, "sanity"); 1715 } 1716 } 1717 } 1718 } 1719 #endif 1720 1721 // Optimize ideal graph. 1722 void ConnectionGraph::optimize_ideal_graph(GrowableArray<Node*>& ptr_cmp_worklist, 1723 GrowableArray<Node*>& storestore_worklist) { 1724 Compile* C = _compile; 1725 PhaseIterGVN* igvn = _igvn; 1726 if (EliminateLocks) { 1727 // Mark locks before changing ideal graph. 1728 int cnt = C->macro_count(); 1729 for( int i=0; i < cnt; i++ ) { 1730 Node *n = C->macro_node(i); 1731 if (n->is_AbstractLock()) { // Lock and Unlock nodes 1732 AbstractLockNode* alock = n->as_AbstractLock(); 1733 if (!alock->is_non_esc_obj()) { 1734 if (not_global_escape(alock->obj_node())) { 1735 assert(!alock->is_eliminated() || alock->is_coarsened(), "sanity"); 1736 // The lock could be marked eliminated by lock coarsening 1737 // code during first IGVN before EA. Replace coarsened flag 1738 // to eliminate all associated locks/unlocks. 1739 alock->set_non_esc_obj(); 1740 } 1741 } 1742 } 1743 } 1744 } 1745 1746 if (OptimizePtrCompare) { 1747 // Add ConI(#CC_GT) and ConI(#CC_EQ). 1748 _pcmp_neq = igvn->makecon(TypeInt::CC_GT); 1749 _pcmp_eq = igvn->makecon(TypeInt::CC_EQ); 1750 // Optimize objects compare. 1751 while (ptr_cmp_worklist.length() != 0) { 1752 Node *n = ptr_cmp_worklist.pop(); 1753 Node *res = optimize_ptr_compare(n); 1754 if (res != NULL) { 1755 #ifndef PRODUCT 1756 if (PrintOptimizePtrCompare) { 1757 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")); 1758 if (Verbose) { 1759 n->dump(1); 1760 } 1761 } 1762 #endif 1763 igvn->replace_node(n, res); 1764 } 1765 } 1766 // cleanup 1767 if (_pcmp_neq->outcnt() == 0) 1768 igvn->hash_delete(_pcmp_neq); 1769 if (_pcmp_eq->outcnt() == 0) 1770 igvn->hash_delete(_pcmp_eq); 1771 } 1772 1773 // For MemBarStoreStore nodes added in library_call.cpp, check 1774 // escape status of associated AllocateNode and optimize out 1775 // MemBarStoreStore node if the allocated object never escapes. 1776 while (storestore_worklist.length() != 0) { 1777 Node *n = storestore_worklist.pop(); 1778 MemBarStoreStoreNode *storestore = n ->as_MemBarStoreStore(); 1779 Node *alloc = storestore->in(MemBarNode::Precedent)->in(0); 1780 assert (alloc->is_Allocate(), "storestore should point to AllocateNode"); 1781 if (not_global_escape(alloc)) { 1782 MemBarNode* mb = MemBarNode::make(C, Op_MemBarCPUOrder, Compile::AliasIdxBot); 1783 mb->init_req(TypeFunc::Memory, storestore->in(TypeFunc::Memory)); 1784 mb->init_req(TypeFunc::Control, storestore->in(TypeFunc::Control)); 1785 igvn->register_new_node_with_optimizer(mb); 1786 igvn->replace_node(storestore, mb); 1787 } 1788 } 1789 } 1790 1791 // Optimize objects compare. 1792 Node* ConnectionGraph::optimize_ptr_compare(Node* n) { 1793 assert(OptimizePtrCompare, "sanity"); 1794 PointsToNode* ptn1 = ptnode_adr(n->in(1)->_idx); 1795 PointsToNode* ptn2 = ptnode_adr(n->in(2)->_idx); 1796 JavaObjectNode* jobj1 = unique_java_object(n->in(1)); 1797 JavaObjectNode* jobj2 = unique_java_object(n->in(2)); 1798 assert(ptn1->is_JavaObject() || ptn1->is_LocalVar(), "sanity"); 1799 assert(ptn2->is_JavaObject() || ptn2->is_LocalVar(), "sanity"); 1800 1801 // Check simple cases first. 1802 if (jobj1 != NULL) { 1803 if (jobj1->escape_state() == PointsToNode::NoEscape) { 1804 if (jobj1 == jobj2) { 1805 // Comparing the same not escaping object. 1806 return _pcmp_eq; 1807 } 1808 Node* obj = jobj1->ideal_node(); 1809 // Comparing not escaping allocation. 1810 if ((obj->is_Allocate() || obj->is_CallStaticJava()) && 1811 !ptn2->points_to(jobj1)) { 1812 return _pcmp_neq; // This includes nullness check. 1813 } 1814 } 1815 } 1816 if (jobj2 != NULL) { 1817 if (jobj2->escape_state() == PointsToNode::NoEscape) { 1818 Node* obj = jobj2->ideal_node(); 1819 // Comparing not escaping allocation. 1820 if ((obj->is_Allocate() || obj->is_CallStaticJava()) && 1821 !ptn1->points_to(jobj2)) { 1822 return _pcmp_neq; // This includes nullness check. 1823 } 1824 } 1825 } 1826 if (jobj1 != NULL && jobj1 != phantom_obj && 1827 jobj2 != NULL && jobj2 != phantom_obj && 1828 jobj1->ideal_node()->is_Con() && 1829 jobj2->ideal_node()->is_Con()) { 1830 // Klass or String constants compare. Need to be careful with 1831 // compressed pointers - compare types of ConN and ConP instead of nodes. 1832 const Type* t1 = jobj1->ideal_node()->get_ptr_type(); 1833 const Type* t2 = jobj2->ideal_node()->get_ptr_type(); 1834 if (t1->make_ptr() == t2->make_ptr()) { 1835 return _pcmp_eq; 1836 } else { 1837 return _pcmp_neq; 1838 } 1839 } 1840 if (ptn1->meet(ptn2)) { 1841 return NULL; // Sets are not disjoint 1842 } 1843 1844 // Sets are disjoint. 1845 bool set1_has_unknown_ptr = ptn1->points_to(phantom_obj); 1846 bool set2_has_unknown_ptr = ptn2->points_to(phantom_obj); 1847 bool set1_has_null_ptr = ptn1->points_to(null_obj); 1848 bool set2_has_null_ptr = ptn2->points_to(null_obj); 1849 if (set1_has_unknown_ptr && set2_has_null_ptr || 1850 set2_has_unknown_ptr && set1_has_null_ptr) { 1851 // Check nullness of unknown object. 1852 return NULL; 1853 } 1854 1855 // Disjointness by itself is not sufficient since 1856 // alias analysis is not complete for escaped objects. 1857 // Disjoint sets are definitely unrelated only when 1858 // at least one set has only not escaping allocations. 1859 if (!set1_has_unknown_ptr && !set1_has_null_ptr) { 1860 if (ptn1->non_escaping_allocation()) { 1861 return _pcmp_neq; 1862 } 1863 } 1864 if (!set2_has_unknown_ptr && !set2_has_null_ptr) { 1865 if (ptn2->non_escaping_allocation()) { 1866 return _pcmp_neq; 1867 } 1868 } 1869 return NULL; 1870 } 1871 1872 // Connection Graph constuction functions. 1873 1874 void ConnectionGraph::add_local_var(Node *n, PointsToNode::EscapeState es) { 1875 PointsToNode* ptadr = _nodes.at(n->_idx); 1876 if (ptadr != NULL) { 1877 assert(ptadr->is_LocalVar() && ptadr->ideal_node() == n, "sanity"); 1878 return; 1879 } 1880 Compile* C = _compile; 1881 ptadr = new (C->comp_arena()) LocalVarNode(C, n, es); 1882 _nodes.at_put(n->_idx, ptadr); 1883 } 1884 1885 void ConnectionGraph::add_java_object(Node *n, PointsToNode::EscapeState es) { 1886 PointsToNode* ptadr = _nodes.at(n->_idx); 1887 if (ptadr != NULL) { 1888 assert(ptadr->is_JavaObject() && ptadr->ideal_node() == n, "sanity"); 1889 return; 1890 } 1891 Compile* C = _compile; 1892 ptadr = new (C->comp_arena()) JavaObjectNode(C, n, es); 1893 _nodes.at_put(n->_idx, ptadr); 1894 } 1895 1896 void ConnectionGraph::add_field(Node *n, PointsToNode::EscapeState es, int offset) { 1897 PointsToNode* ptadr = _nodes.at(n->_idx); 1898 if (ptadr != NULL) { 1899 assert(ptadr->is_Field() && ptadr->ideal_node() == n, "sanity"); 1900 return; 1901 } 1902 bool unsafe = false; 1903 bool is_oop = is_oop_field(n, offset, &unsafe); 1904 if (unsafe) { 1905 es = PointsToNode::GlobalEscape; 1906 } 1907 Compile* C = _compile; 1908 FieldNode* field = new (C->comp_arena()) FieldNode(C, n, es, offset, is_oop); 1909 _nodes.at_put(n->_idx, field); 1910 } 1911 1912 void ConnectionGraph::add_arraycopy(Node *n, PointsToNode::EscapeState es, 1913 PointsToNode* src, PointsToNode* dst) { 1914 assert(!src->is_Field() && !dst->is_Field(), "only for JavaObject and LocalVar"); 1915 assert((src != null_obj) && (dst != null_obj), "not for ConP NULL"); 1916 PointsToNode* ptadr = _nodes.at(n->_idx); 1917 if (ptadr != NULL) { 1918 assert(ptadr->is_Arraycopy() && ptadr->ideal_node() == n, "sanity"); 1919 return; 1920 } 1921 Compile* C = _compile; 1922 ptadr = new (C->comp_arena()) ArraycopyNode(C, n, es); 1923 _nodes.at_put(n->_idx, ptadr); 1924 // Add edge from arraycopy node to source object. 1925 (void)add_edge(ptadr, src); 1926 src->set_arraycopy_src(); 1927 // Add edge from destination object to arraycopy node. 1928 (void)add_edge(dst, ptadr); 1929 dst->set_arraycopy_dst(); 1930 } 1931 1932 bool ConnectionGraph::is_oop_field(Node* n, int offset, bool* unsafe) { 1933 const Type* adr_type = n->as_AddP()->bottom_type(); 1934 BasicType bt = T_INT; 1935 if (offset == Type::OffsetBot) { 1936 // Check only oop fields. 1937 if (!adr_type->isa_aryptr() || 1938 (adr_type->isa_aryptr()->klass() == NULL) || 1939 adr_type->isa_aryptr()->klass()->is_obj_array_klass()) { 1940 // OffsetBot is used to reference array's element. Ignore first AddP. 1941 if (find_second_addp(n, n->in(AddPNode::Base)) == NULL) { 1942 bt = T_OBJECT; 1943 } 1944 } 1945 } else if (offset != oopDesc::klass_offset_in_bytes()) { 1946 if (adr_type->isa_instptr()) { 1947 ciField* field = _compile->alias_type(adr_type->isa_instptr())->field(); 1948 if (field != NULL) { 1949 bt = field->layout_type(); 1950 } else { 1951 // Check for unsafe oop field access 1952 for (DUIterator_Fast imax, i = n->fast_outs(imax); i < imax; i++) { 1953 int opcode = n->fast_out(i)->Opcode(); 1954 if (opcode == Op_StoreP || opcode == Op_LoadP || 1955 opcode == Op_StoreN || opcode == Op_LoadN) { 1956 bt = T_OBJECT; 1957 (*unsafe) = true; 1958 break; 1959 } 1960 } 1961 } 1962 } else if (adr_type->isa_aryptr()) { 1963 if (offset == arrayOopDesc::length_offset_in_bytes()) { 1964 // Ignore array length load. 1965 } else if (find_second_addp(n, n->in(AddPNode::Base)) != NULL) { 1966 // Ignore first AddP. 1967 } else { 1968 const Type* elemtype = adr_type->isa_aryptr()->elem(); 1969 bt = elemtype->array_element_basic_type(); 1970 } 1971 } else if (adr_type->isa_rawptr() || adr_type->isa_klassptr()) { 1972 // Allocation initialization, ThreadLocal field access, unsafe access 1973 for (DUIterator_Fast imax, i = n->fast_outs(imax); i < imax; i++) { 1974 int opcode = n->fast_out(i)->Opcode(); 1975 if (opcode == Op_StoreP || opcode == Op_LoadP || 1976 opcode == Op_StoreN || opcode == Op_LoadN) { 1977 bt = T_OBJECT; 1978 break; 1979 } 1980 } 1981 } 1982 } 1983 return (bt == T_OBJECT || bt == T_NARROWOOP || bt == T_ARRAY); 1984 } 1985 1986 // Returns unique pointed java object or NULL. 1987 JavaObjectNode* ConnectionGraph::unique_java_object(Node *n) { 1988 assert(!_collecting, "should not call when contructed graph"); 1989 // If the node was created after the escape computation we can't answer. 1990 uint idx = n->_idx; 1991 if (idx >= nodes_size()) { 1992 return NULL; 1993 } 1994 PointsToNode* ptn = ptnode_adr(idx); 1995 if (ptn->is_JavaObject()) { 1996 return ptn->as_JavaObject(); 1997 } 1998 assert(ptn->is_LocalVar(), "sanity"); 1999 // Check all java objects it points to. 2000 JavaObjectNode* jobj = NULL; 2001 for (EdgeIterator i(ptn); i.has_next(); i.next()) { 2002 PointsToNode* e = i.get(); 2003 if (e->is_JavaObject()) { 2004 if (jobj == NULL) { 2005 jobj = e->as_JavaObject(); 2006 } else if (jobj != e) { 2007 return NULL; 2008 } 2009 } 2010 } 2011 return jobj; 2012 } 2013 2014 // Return true if this node points only to non-escaping allocations. 2015 bool PointsToNode::non_escaping_allocation() { 2016 if (is_JavaObject()) { 2017 Node* n = ideal_node(); 2018 if (n->is_Allocate() || n->is_CallStaticJava()) { 2019 return (escape_state() == PointsToNode::NoEscape); 2020 } else { 2021 return false; 2022 } 2023 } 2024 assert(is_LocalVar(), "sanity"); 2025 // Check all java objects it points to. 2026 for (EdgeIterator i(this); i.has_next(); i.next()) { 2027 PointsToNode* e = i.get(); 2028 if (e->is_JavaObject()) { 2029 Node* n = e->ideal_node(); 2030 if ((e->escape_state() != PointsToNode::NoEscape) || 2031 !(n->is_Allocate() || n->is_CallStaticJava())) { 2032 return false; 2033 } 2034 } 2035 } 2036 return true; 2037 } 2038 2039 // Return true if we know the node does not escape globally. 2040 bool ConnectionGraph::not_global_escape(Node *n) { 2041 assert(!_collecting, "should not call during graph construction"); 2042 // If the node was created after the escape computation we can't answer. 2043 uint idx = n->_idx; 2044 if (idx >= nodes_size()) { 2045 return false; 2046 } 2047 PointsToNode* ptn = ptnode_adr(idx); 2048 PointsToNode::EscapeState es = ptn->escape_state(); 2049 // If we have already computed a value, return it. 2050 if (es >= PointsToNode::GlobalEscape) 2051 return false; 2052 if (ptn->is_JavaObject()) { 2053 return true; // (es < PointsToNode::GlobalEscape); 2054 } 2055 assert(ptn->is_LocalVar(), "sanity"); 2056 // Check all java objects it points to. 2057 for (EdgeIterator i(ptn); i.has_next(); i.next()) { 2058 if (i.get()->escape_state() >= PointsToNode::GlobalEscape) 2059 return false; 2060 } 2061 return true; 2062 } 2063 2064 2065 // Helper functions 2066 2067 // Return true if this node points to specified node or nodes it points to. 2068 bool PointsToNode::points_to(JavaObjectNode* ptn) const { 2069 if (is_JavaObject()) { 2070 return (this == ptn); 2071 } 2072 assert(is_LocalVar() || is_Field(), "sanity"); 2073 for (EdgeIterator i(this); i.has_next(); i.next()) { 2074 if (i.get() == ptn) 2075 return true; 2076 } 2077 return false; 2078 } 2079 2080 // Return true if one node points to an other. 2081 bool PointsToNode::meet(PointsToNode* ptn) { 2082 if (this == ptn) { 2083 return true; 2084 } else if (ptn->is_JavaObject()) { 2085 return this->points_to(ptn->as_JavaObject()); 2086 } else if (this->is_JavaObject()) { 2087 return ptn->points_to(this->as_JavaObject()); 2088 } 2089 assert(this->is_LocalVar() && ptn->is_LocalVar(), "sanity"); 2090 int ptn_count = ptn->edge_count(); 2091 for (EdgeIterator i(this); i.has_next(); i.next()) { 2092 PointsToNode* this_e = i.get(); 2093 for (int j = 0; j < ptn_count; j++) { 2094 if (this_e == ptn->edge(j)) 2095 return true; 2096 } 2097 } 2098 return false; 2099 } 2100 2101 #ifdef ASSERT 2102 // Return true if bases point to this java object. 2103 bool FieldNode::has_base(JavaObjectNode* jobj) const { 2104 for (BaseIterator i(this); i.has_next(); i.next()) { 2105 if (i.get() == jobj) 2106 return true; 2107 } 2108 return false; 2109 } 2110 #endif 2111 2112 int ConnectionGraph::address_offset(Node* adr, PhaseTransform *phase) { 2113 const Type *adr_type = phase->type(adr); 2114 if (adr->is_AddP() && adr_type->isa_oopptr() == NULL && 2115 adr->in(AddPNode::Address)->is_Proj() && 2116 adr->in(AddPNode::Address)->in(0)->is_Allocate()) { 2117 // We are computing a raw address for a store captured by an Initialize 2118 // compute an appropriate address type. AddP cases #3 and #5 (see below). 2119 int offs = (int)phase->find_intptr_t_con(adr->in(AddPNode::Offset), Type::OffsetBot); 2120 assert(offs != Type::OffsetBot || 2121 adr->in(AddPNode::Address)->in(0)->is_AllocateArray(), 2122 "offset must be a constant or it is initialization of array"); 2123 return offs; 2124 } 2125 const TypePtr *t_ptr = adr_type->isa_ptr(); 2126 assert(t_ptr != NULL, "must be a pointer type"); 2127 return t_ptr->offset(); 2128 } 2129 2130 Node* ConnectionGraph::get_addp_base(Node *addp) { 2131 assert(addp->is_AddP(), "must be AddP"); 2132 // 2133 // AddP cases for Base and Address inputs: 2134 // case #1. Direct object's field reference: 2135 // Allocate 2136 // | 2137 // Proj #5 ( oop result ) 2138 // | 2139 // CheckCastPP (cast to instance type) 2140 // | | 2141 // AddP ( base == address ) 2142 // 2143 // case #2. Indirect object's field reference: 2144 // Phi 2145 // | 2146 // CastPP (cast to instance type) 2147 // | | 2148 // AddP ( base == address ) 2149 // 2150 // case #3. Raw object's field reference for Initialize node: 2151 // Allocate 2152 // | 2153 // Proj #5 ( oop result ) 2154 // top | 2155 // \ | 2156 // AddP ( base == top ) 2157 // 2158 // case #4. Array's element reference: 2159 // {CheckCastPP | CastPP} 2160 // | | | 2161 // | AddP ( array's element offset ) 2162 // | | 2163 // AddP ( array's offset ) 2164 // 2165 // case #5. Raw object's field reference for arraycopy stub call: 2166 // The inline_native_clone() case when the arraycopy stub is called 2167 // after the allocation before Initialize and CheckCastPP nodes. 2168 // Allocate 2169 // | 2170 // Proj #5 ( oop result ) 2171 // | | 2172 // AddP ( base == address ) 2173 // 2174 // case #6. Constant Pool, ThreadLocal, CastX2P or 2175 // Raw object's field reference: 2176 // {ConP, ThreadLocal, CastX2P, raw Load} 2177 // top | 2178 // \ | 2179 // AddP ( base == top ) 2180 // 2181 // case #7. Klass's field reference. 2182 // LoadKlass 2183 // | | 2184 // AddP ( base == address ) 2185 // 2186 // case #8. narrow Klass's field reference. 2187 // LoadNKlass 2188 // | 2189 // DecodeN 2190 // | | 2191 // AddP ( base == address ) 2192 // 2193 Node *base = addp->in(AddPNode::Base); 2194 if (base->uncast()->is_top()) { // The AddP case #3 and #6. 2195 base = addp->in(AddPNode::Address); 2196 while (base->is_AddP()) { 2197 // Case #6 (unsafe access) may have several chained AddP nodes. 2198 assert(base->in(AddPNode::Base)->uncast()->is_top(), "expected unsafe access address only"); 2199 base = base->in(AddPNode::Address); 2200 } 2201 Node* uncast_base = base->uncast(); 2202 int opcode = uncast_base->Opcode(); 2203 assert(opcode == Op_ConP || opcode == Op_ThreadLocal || 2204 opcode == Op_CastX2P || uncast_base->is_DecodeNarrowPtr() || 2205 (uncast_base->is_Mem() && uncast_base->bottom_type() == TypeRawPtr::NOTNULL) || 2206 (uncast_base->is_Proj() && uncast_base->in(0)->is_Allocate()), "sanity"); 2207 } 2208 return base; 2209 } 2210 2211 Node* ConnectionGraph::find_second_addp(Node* addp, Node* n) { 2212 assert(addp->is_AddP() && addp->outcnt() > 0, "Don't process dead nodes"); 2213 Node* addp2 = addp->raw_out(0); 2214 if (addp->outcnt() == 1 && addp2->is_AddP() && 2215 addp2->in(AddPNode::Base) == n && 2216 addp2->in(AddPNode::Address) == addp) { 2217 assert(addp->in(AddPNode::Base) == n, "expecting the same base"); 2218 // 2219 // Find array's offset to push it on worklist first and 2220 // as result process an array's element offset first (pushed second) 2221 // to avoid CastPP for the array's offset. 2222 // Otherwise the inserted CastPP (LocalVar) will point to what 2223 // the AddP (Field) points to. Which would be wrong since 2224 // the algorithm expects the CastPP has the same point as 2225 // as AddP's base CheckCastPP (LocalVar). 2226 // 2227 // ArrayAllocation 2228 // | 2229 // CheckCastPP 2230 // | 2231 // memProj (from ArrayAllocation CheckCastPP) 2232 // | || 2233 // | || Int (element index) 2234 // | || | ConI (log(element size)) 2235 // | || | / 2236 // | || LShift 2237 // | || / 2238 // | AddP (array's element offset) 2239 // | | 2240 // | | ConI (array's offset: #12(32-bits) or #24(64-bits)) 2241 // | / / 2242 // AddP (array's offset) 2243 // | 2244 // Load/Store (memory operation on array's element) 2245 // 2246 return addp2; 2247 } 2248 return NULL; 2249 } 2250 2251 // 2252 // Adjust the type and inputs of an AddP which computes the 2253 // address of a field of an instance 2254 // 2255 bool ConnectionGraph::split_AddP(Node *addp, Node *base) { 2256 PhaseGVN* igvn = _igvn; 2257 const TypeOopPtr *base_t = igvn->type(base)->isa_oopptr(); 2258 assert(base_t != NULL && base_t->is_known_instance(), "expecting instance oopptr"); 2259 const TypeOopPtr *t = igvn->type(addp)->isa_oopptr(); 2260 if (t == NULL) { 2261 // We are computing a raw address for a store captured by an Initialize 2262 // compute an appropriate address type (cases #3 and #5). 2263 assert(igvn->type(addp) == TypeRawPtr::NOTNULL, "must be raw pointer"); 2264 assert(addp->in(AddPNode::Address)->is_Proj(), "base of raw address must be result projection from allocation"); 2265 intptr_t offs = (int)igvn->find_intptr_t_con(addp->in(AddPNode::Offset), Type::OffsetBot); 2266 assert(offs != Type::OffsetBot, "offset must be a constant"); 2267 t = base_t->add_offset(offs)->is_oopptr(); 2268 } 2269 int inst_id = base_t->instance_id(); 2270 assert(!t->is_known_instance() || t->instance_id() == inst_id, 2271 "old type must be non-instance or match new type"); 2272 2273 // The type 't' could be subclass of 'base_t'. 2274 // As result t->offset() could be large then base_t's size and it will 2275 // cause the failure in add_offset() with narrow oops since TypeOopPtr() 2276 // constructor verifies correctness of the offset. 2277 // 2278 // It could happened on subclass's branch (from the type profiling 2279 // inlining) which was not eliminated during parsing since the exactness 2280 // of the allocation type was not propagated to the subclass type check. 2281 // 2282 // Or the type 't' could be not related to 'base_t' at all. 2283 // It could happened when CHA type is different from MDO type on a dead path 2284 // (for example, from instanceof check) which is not collapsed during parsing. 2285 // 2286 // Do nothing for such AddP node and don't process its users since 2287 // this code branch will go away. 2288 // 2289 if (!t->is_known_instance() && 2290 !base_t->klass()->is_subtype_of(t->klass())) { 2291 return false; // bail out 2292 } 2293 const TypeOopPtr *tinst = base_t->add_offset(t->offset())->is_oopptr(); 2294 // Do NOT remove the next line: ensure a new alias index is allocated 2295 // for the instance type. Note: C++ will not remove it since the call 2296 // has side effect. 2297 int alias_idx = _compile->get_alias_index(tinst); 2298 igvn->set_type(addp, tinst); 2299 // record the allocation in the node map 2300 set_map(addp, get_map(base->_idx)); 2301 // Set addp's Base and Address to 'base'. 2302 Node *abase = addp->in(AddPNode::Base); 2303 Node *adr = addp->in(AddPNode::Address); 2304 if (adr->is_Proj() && adr->in(0)->is_Allocate() && 2305 adr->in(0)->_idx == (uint)inst_id) { 2306 // Skip AddP cases #3 and #5. 2307 } else { 2308 assert(!abase->is_top(), "sanity"); // AddP case #3 2309 if (abase != base) { 2310 igvn->hash_delete(addp); 2311 addp->set_req(AddPNode::Base, base); 2312 if (abase == adr) { 2313 addp->set_req(AddPNode::Address, base); 2314 } else { 2315 // AddP case #4 (adr is array's element offset AddP node) 2316 #ifdef ASSERT 2317 const TypeOopPtr *atype = igvn->type(adr)->isa_oopptr(); 2318 assert(adr->is_AddP() && atype != NULL && 2319 atype->instance_id() == inst_id, "array's element offset should be processed first"); 2320 #endif 2321 } 2322 igvn->hash_insert(addp); 2323 } 2324 } 2325 // Put on IGVN worklist since at least addp's type was changed above. 2326 record_for_optimizer(addp); 2327 return true; 2328 } 2329 2330 // 2331 // Create a new version of orig_phi if necessary. Returns either the newly 2332 // created phi or an existing phi. Sets create_new to indicate whether a new 2333 // phi was created. Cache the last newly created phi in the node map. 2334 // 2335 PhiNode *ConnectionGraph::create_split_phi(PhiNode *orig_phi, int alias_idx, GrowableArray<PhiNode *> &orig_phi_worklist, bool &new_created) { 2336 Compile *C = _compile; 2337 PhaseGVN* igvn = _igvn; 2338 new_created = false; 2339 int phi_alias_idx = C->get_alias_index(orig_phi->adr_type()); 2340 // nothing to do if orig_phi is bottom memory or matches alias_idx 2341 if (phi_alias_idx == alias_idx) { 2342 return orig_phi; 2343 } 2344 // Have we recently created a Phi for this alias index? 2345 PhiNode *result = get_map_phi(orig_phi->_idx); 2346 if (result != NULL && C->get_alias_index(result->adr_type()) == alias_idx) { 2347 return result; 2348 } 2349 // Previous check may fail when the same wide memory Phi was split into Phis 2350 // for different memory slices. Search all Phis for this region. 2351 if (result != NULL) { 2352 Node* region = orig_phi->in(0); 2353 for (DUIterator_Fast imax, i = region->fast_outs(imax); i < imax; i++) { 2354 Node* phi = region->fast_out(i); 2355 if (phi->is_Phi() && 2356 C->get_alias_index(phi->as_Phi()->adr_type()) == alias_idx) { 2357 assert(phi->_idx >= nodes_size(), "only new Phi per instance memory slice"); 2358 return phi->as_Phi(); 2359 } 2360 } 2361 } 2362 if ((int) (C->live_nodes() + 2*NodeLimitFudgeFactor) > MaxNodeLimit) { 2363 if (C->do_escape_analysis() == true && !C->failing()) { 2364 // Retry compilation without escape analysis. 2365 // If this is the first failure, the sentinel string will "stick" 2366 // to the Compile object, and the C2Compiler will see it and retry. 2367 C->record_failure(C2Compiler::retry_no_escape_analysis()); 2368 } 2369 return NULL; 2370 } 2371 orig_phi_worklist.append_if_missing(orig_phi); 2372 const TypePtr *atype = C->get_adr_type(alias_idx); 2373 result = PhiNode::make(orig_phi->in(0), NULL, Type::MEMORY, atype); 2374 C->copy_node_notes_to(result, orig_phi); 2375 igvn->set_type(result, result->bottom_type()); 2376 record_for_optimizer(result); 2377 set_map(orig_phi, result); 2378 new_created = true; 2379 return result; 2380 } 2381 2382 // 2383 // Return a new version of Memory Phi "orig_phi" with the inputs having the 2384 // specified alias index. 2385 // 2386 PhiNode *ConnectionGraph::split_memory_phi(PhiNode *orig_phi, int alias_idx, GrowableArray<PhiNode *> &orig_phi_worklist) { 2387 assert(alias_idx != Compile::AliasIdxBot, "can't split out bottom memory"); 2388 Compile *C = _compile; 2389 PhaseGVN* igvn = _igvn; 2390 bool new_phi_created; 2391 PhiNode *result = create_split_phi(orig_phi, alias_idx, orig_phi_worklist, new_phi_created); 2392 if (!new_phi_created) { 2393 return result; 2394 } 2395 GrowableArray<PhiNode *> phi_list; 2396 GrowableArray<uint> cur_input; 2397 PhiNode *phi = orig_phi; 2398 uint idx = 1; 2399 bool finished = false; 2400 while(!finished) { 2401 while (idx < phi->req()) { 2402 Node *mem = find_inst_mem(phi->in(idx), alias_idx, orig_phi_worklist); 2403 if (mem != NULL && mem->is_Phi()) { 2404 PhiNode *newphi = create_split_phi(mem->as_Phi(), alias_idx, orig_phi_worklist, new_phi_created); 2405 if (new_phi_created) { 2406 // found an phi for which we created a new split, push current one on worklist and begin 2407 // processing new one 2408 phi_list.push(phi); 2409 cur_input.push(idx); 2410 phi = mem->as_Phi(); 2411 result = newphi; 2412 idx = 1; 2413 continue; 2414 } else { 2415 mem = newphi; 2416 } 2417 } 2418 if (C->failing()) { 2419 return NULL; 2420 } 2421 result->set_req(idx++, mem); 2422 } 2423 #ifdef ASSERT 2424 // verify that the new Phi has an input for each input of the original 2425 assert( phi->req() == result->req(), "must have same number of inputs."); 2426 assert( result->in(0) != NULL && result->in(0) == phi->in(0), "regions must match"); 2427 #endif 2428 // Check if all new phi's inputs have specified alias index. 2429 // Otherwise use old phi. 2430 for (uint i = 1; i < phi->req(); i++) { 2431 Node* in = result->in(i); 2432 assert((phi->in(i) == NULL) == (in == NULL), "inputs must correspond."); 2433 } 2434 // we have finished processing a Phi, see if there are any more to do 2435 finished = (phi_list.length() == 0 ); 2436 if (!finished) { 2437 phi = phi_list.pop(); 2438 idx = cur_input.pop(); 2439 PhiNode *prev_result = get_map_phi(phi->_idx); 2440 prev_result->set_req(idx++, result); 2441 result = prev_result; 2442 } 2443 } 2444 return result; 2445 } 2446 2447 // 2448 // The next methods are derived from methods in MemNode. 2449 // 2450 Node* ConnectionGraph::step_through_mergemem(MergeMemNode *mmem, int alias_idx, const TypeOopPtr *toop) { 2451 Node *mem = mmem; 2452 // TypeOopPtr::NOTNULL+any is an OOP with unknown offset - generally 2453 // means an array I have not precisely typed yet. Do not do any 2454 // alias stuff with it any time soon. 2455 if (toop->base() != Type::AnyPtr && 2456 !(toop->klass() != NULL && 2457 toop->klass()->is_java_lang_Object() && 2458 toop->offset() == Type::OffsetBot)) { 2459 mem = mmem->memory_at(alias_idx); 2460 // Update input if it is progress over what we have now 2461 } 2462 return mem; 2463 } 2464 2465 // 2466 // Move memory users to their memory slices. 2467 // 2468 void ConnectionGraph::move_inst_mem(Node* n, GrowableArray<PhiNode *> &orig_phis) { 2469 Compile* C = _compile; 2470 PhaseGVN* igvn = _igvn; 2471 const TypePtr* tp = igvn->type(n->in(MemNode::Address))->isa_ptr(); 2472 assert(tp != NULL, "ptr type"); 2473 int alias_idx = C->get_alias_index(tp); 2474 int general_idx = C->get_general_index(alias_idx); 2475 2476 // Move users first 2477 for (DUIterator_Fast imax, i = n->fast_outs(imax); i < imax; i++) { 2478 Node* use = n->fast_out(i); 2479 if (use->is_MergeMem()) { 2480 MergeMemNode* mmem = use->as_MergeMem(); 2481 assert(n == mmem->memory_at(alias_idx), "should be on instance memory slice"); 2482 if (n != mmem->memory_at(general_idx) || alias_idx == general_idx) { 2483 continue; // Nothing to do 2484 } 2485 // Replace previous general reference to mem node. 2486 uint orig_uniq = C->unique(); 2487 Node* m = find_inst_mem(n, general_idx, orig_phis); 2488 assert(orig_uniq == C->unique(), "no new nodes"); 2489 mmem->set_memory_at(general_idx, m); 2490 --imax; 2491 --i; 2492 } else if (use->is_MemBar()) { 2493 assert(!use->is_Initialize(), "initializing stores should not be moved"); 2494 if (use->req() > MemBarNode::Precedent && 2495 use->in(MemBarNode::Precedent) == n) { 2496 // Don't move related membars. 2497 record_for_optimizer(use); 2498 continue; 2499 } 2500 tp = use->as_MemBar()->adr_type()->isa_ptr(); 2501 if (tp != NULL && C->get_alias_index(tp) == alias_idx || 2502 alias_idx == general_idx) { 2503 continue; // Nothing to do 2504 } 2505 // Move to general memory slice. 2506 uint orig_uniq = C->unique(); 2507 Node* m = find_inst_mem(n, general_idx, orig_phis); 2508 assert(orig_uniq == C->unique(), "no new nodes"); 2509 igvn->hash_delete(use); 2510 imax -= use->replace_edge(n, m); 2511 igvn->hash_insert(use); 2512 record_for_optimizer(use); 2513 --i; 2514 #ifdef ASSERT 2515 } else if (use->is_Mem()) { 2516 if (use->Opcode() == Op_StoreCM && use->in(MemNode::OopStore) == n) { 2517 // Don't move related cardmark. 2518 continue; 2519 } 2520 // Memory nodes should have new memory input. 2521 tp = igvn->type(use->in(MemNode::Address))->isa_ptr(); 2522 assert(tp != NULL, "ptr type"); 2523 int idx = C->get_alias_index(tp); 2524 assert(get_map(use->_idx) != NULL || idx == alias_idx, 2525 "Following memory nodes should have new memory input or be on the same memory slice"); 2526 } else if (use->is_Phi()) { 2527 // Phi nodes should be split and moved already. 2528 tp = use->as_Phi()->adr_type()->isa_ptr(); 2529 assert(tp != NULL, "ptr type"); 2530 int idx = C->get_alias_index(tp); 2531 assert(idx == alias_idx, "Following Phi nodes should be on the same memory slice"); 2532 } else { 2533 use->dump(); 2534 assert(false, "should not be here"); 2535 #endif 2536 } 2537 } 2538 } 2539 2540 // 2541 // Search memory chain of "mem" to find a MemNode whose address 2542 // is the specified alias index. 2543 // 2544 Node* ConnectionGraph::find_inst_mem(Node *orig_mem, int alias_idx, GrowableArray<PhiNode *> &orig_phis) { 2545 if (orig_mem == NULL) 2546 return orig_mem; 2547 Compile* C = _compile; 2548 PhaseGVN* igvn = _igvn; 2549 const TypeOopPtr *toop = C->get_adr_type(alias_idx)->isa_oopptr(); 2550 bool is_instance = (toop != NULL) && toop->is_known_instance(); 2551 Node *start_mem = C->start()->proj_out(TypeFunc::Memory); 2552 Node *prev = NULL; 2553 Node *result = orig_mem; 2554 while (prev != result) { 2555 prev = result; 2556 if (result == start_mem) 2557 break; // hit one of our sentinels 2558 if (result->is_Mem()) { 2559 const Type *at = igvn->type(result->in(MemNode::Address)); 2560 if (at == Type::TOP) 2561 break; // Dead 2562 assert (at->isa_ptr() != NULL, "pointer type required."); 2563 int idx = C->get_alias_index(at->is_ptr()); 2564 if (idx == alias_idx) 2565 break; // Found 2566 if (!is_instance && (at->isa_oopptr() == NULL || 2567 !at->is_oopptr()->is_known_instance())) { 2568 break; // Do not skip store to general memory slice. 2569 } 2570 result = result->in(MemNode::Memory); 2571 } 2572 if (!is_instance) 2573 continue; // don't search further for non-instance types 2574 // skip over a call which does not affect this memory slice 2575 if (result->is_Proj() && result->as_Proj()->_con == TypeFunc::Memory) { 2576 Node *proj_in = result->in(0); 2577 if (proj_in->is_Allocate() && proj_in->_idx == (uint)toop->instance_id()) { 2578 break; // hit one of our sentinels 2579 } else if (proj_in->is_Call()) { 2580 CallNode *call = proj_in->as_Call(); 2581 if (!call->may_modify(toop, igvn)) { 2582 result = call->in(TypeFunc::Memory); 2583 } 2584 } else if (proj_in->is_Initialize()) { 2585 AllocateNode* alloc = proj_in->as_Initialize()->allocation(); 2586 // Stop if this is the initialization for the object instance which 2587 // which contains this memory slice, otherwise skip over it. 2588 if (alloc == NULL || alloc->_idx != (uint)toop->instance_id()) { 2589 result = proj_in->in(TypeFunc::Memory); 2590 } 2591 } else if (proj_in->is_MemBar()) { 2592 result = proj_in->in(TypeFunc::Memory); 2593 } 2594 } else if (result->is_MergeMem()) { 2595 MergeMemNode *mmem = result->as_MergeMem(); 2596 result = step_through_mergemem(mmem, alias_idx, toop); 2597 if (result == mmem->base_memory()) { 2598 // Didn't find instance memory, search through general slice recursively. 2599 result = mmem->memory_at(C->get_general_index(alias_idx)); 2600 result = find_inst_mem(result, alias_idx, orig_phis); 2601 if (C->failing()) { 2602 return NULL; 2603 } 2604 mmem->set_memory_at(alias_idx, result); 2605 } 2606 } else if (result->is_Phi() && 2607 C->get_alias_index(result->as_Phi()->adr_type()) != alias_idx) { 2608 Node *un = result->as_Phi()->unique_input(igvn); 2609 if (un != NULL) { 2610 orig_phis.append_if_missing(result->as_Phi()); 2611 result = un; 2612 } else { 2613 break; 2614 } 2615 } else if (result->is_ClearArray()) { 2616 if (!ClearArrayNode::step_through(&result, (uint)toop->instance_id(), igvn)) { 2617 // Can not bypass initialization of the instance 2618 // we are looking for. 2619 break; 2620 } 2621 // Otherwise skip it (the call updated 'result' value). 2622 } else if (result->Opcode() == Op_SCMemProj) { 2623 Node* mem = result->in(0); 2624 Node* adr = NULL; 2625 if (mem->is_LoadStore()) { 2626 adr = mem->in(MemNode::Address); 2627 } else { 2628 assert(mem->Opcode() == Op_EncodeISOArray, "sanity"); 2629 adr = mem->in(3); // Memory edge corresponds to destination array 2630 } 2631 const Type *at = igvn->type(adr); 2632 if (at != Type::TOP) { 2633 assert (at->isa_ptr() != NULL, "pointer type required."); 2634 int idx = C->get_alias_index(at->is_ptr()); 2635 assert(idx != alias_idx, "Object is not scalar replaceable if a LoadStore node access its field"); 2636 break; 2637 } 2638 result = mem->in(MemNode::Memory); 2639 } 2640 } 2641 if (result->is_Phi()) { 2642 PhiNode *mphi = result->as_Phi(); 2643 assert(mphi->bottom_type() == Type::MEMORY, "memory phi required"); 2644 const TypePtr *t = mphi->adr_type(); 2645 if (!is_instance) { 2646 // Push all non-instance Phis on the orig_phis worklist to update inputs 2647 // during Phase 4 if needed. 2648 orig_phis.append_if_missing(mphi); 2649 } else if (C->get_alias_index(t) != alias_idx) { 2650 // Create a new Phi with the specified alias index type. 2651 result = split_memory_phi(mphi, alias_idx, orig_phis); 2652 } 2653 } 2654 // the result is either MemNode, PhiNode, InitializeNode. 2655 return result; 2656 } 2657 2658 // 2659 // Convert the types of unescaped object to instance types where possible, 2660 // propagate the new type information through the graph, and update memory 2661 // edges and MergeMem inputs to reflect the new type. 2662 // 2663 // We start with allocations (and calls which may be allocations) on alloc_worklist. 2664 // The processing is done in 4 phases: 2665 // 2666 // Phase 1: Process possible allocations from alloc_worklist. Create instance 2667 // types for the CheckCastPP for allocations where possible. 2668 // Propagate the the new types through users as follows: 2669 // casts and Phi: push users on alloc_worklist 2670 // AddP: cast Base and Address inputs to the instance type 2671 // push any AddP users on alloc_worklist and push any memnode 2672 // users onto memnode_worklist. 2673 // Phase 2: Process MemNode's from memnode_worklist. compute new address type and 2674 // search the Memory chain for a store with the appropriate type 2675 // address type. If a Phi is found, create a new version with 2676 // the appropriate memory slices from each of the Phi inputs. 2677 // For stores, process the users as follows: 2678 // MemNode: push on memnode_worklist 2679 // MergeMem: push on mergemem_worklist 2680 // Phase 3: Process MergeMem nodes from mergemem_worklist. Walk each memory slice 2681 // moving the first node encountered of each instance type to the 2682 // the input corresponding to its alias index. 2683 // appropriate memory slice. 2684 // Phase 4: Update the inputs of non-instance memory Phis and the Memory input of memnodes. 2685 // 2686 // In the following example, the CheckCastPP nodes are the cast of allocation 2687 // results and the allocation of node 29 is unescaped and eligible to be an 2688 // instance type. 2689 // 2690 // We start with: 2691 // 2692 // 7 Parm #memory 2693 // 10 ConI "12" 2694 // 19 CheckCastPP "Foo" 2695 // 20 AddP _ 19 19 10 Foo+12 alias_index=4 2696 // 29 CheckCastPP "Foo" 2697 // 30 AddP _ 29 29 10 Foo+12 alias_index=4 2698 // 2699 // 40 StoreP 25 7 20 ... alias_index=4 2700 // 50 StoreP 35 40 30 ... alias_index=4 2701 // 60 StoreP 45 50 20 ... alias_index=4 2702 // 70 LoadP _ 60 30 ... alias_index=4 2703 // 80 Phi 75 50 60 Memory alias_index=4 2704 // 90 LoadP _ 80 30 ... alias_index=4 2705 // 100 LoadP _ 80 20 ... alias_index=4 2706 // 2707 // 2708 // Phase 1 creates an instance type for node 29 assigning it an instance id of 24 2709 // and creating a new alias index for node 30. This gives: 2710 // 2711 // 7 Parm #memory 2712 // 10 ConI "12" 2713 // 19 CheckCastPP "Foo" 2714 // 20 AddP _ 19 19 10 Foo+12 alias_index=4 2715 // 29 CheckCastPP "Foo" iid=24 2716 // 30 AddP _ 29 29 10 Foo+12 alias_index=6 iid=24 2717 // 2718 // 40 StoreP 25 7 20 ... alias_index=4 2719 // 50 StoreP 35 40 30 ... alias_index=6 2720 // 60 StoreP 45 50 20 ... alias_index=4 2721 // 70 LoadP _ 60 30 ... alias_index=6 2722 // 80 Phi 75 50 60 Memory alias_index=4 2723 // 90 LoadP _ 80 30 ... alias_index=6 2724 // 100 LoadP _ 80 20 ... alias_index=4 2725 // 2726 // In phase 2, new memory inputs are computed for the loads and stores, 2727 // And a new version of the phi is created. In phase 4, the inputs to 2728 // node 80 are updated and then the memory nodes are updated with the 2729 // values computed in phase 2. This results in: 2730 // 2731 // 7 Parm #memory 2732 // 10 ConI "12" 2733 // 19 CheckCastPP "Foo" 2734 // 20 AddP _ 19 19 10 Foo+12 alias_index=4 2735 // 29 CheckCastPP "Foo" iid=24 2736 // 30 AddP _ 29 29 10 Foo+12 alias_index=6 iid=24 2737 // 2738 // 40 StoreP 25 7 20 ... alias_index=4 2739 // 50 StoreP 35 7 30 ... alias_index=6 2740 // 60 StoreP 45 40 20 ... alias_index=4 2741 // 70 LoadP _ 50 30 ... alias_index=6 2742 // 80 Phi 75 40 60 Memory alias_index=4 2743 // 120 Phi 75 50 50 Memory alias_index=6 2744 // 90 LoadP _ 120 30 ... alias_index=6 2745 // 100 LoadP _ 80 20 ... alias_index=4 2746 // 2747 void ConnectionGraph::split_unique_types(GrowableArray<Node *> &alloc_worklist) { 2748 GrowableArray<Node *> memnode_worklist; 2749 GrowableArray<PhiNode *> orig_phis; 2750 PhaseIterGVN *igvn = _igvn; 2751 uint new_index_start = (uint) _compile->num_alias_types(); 2752 Arena* arena = Thread::current()->resource_area(); 2753 VectorSet visited(arena); 2754 ideal_nodes.clear(); // Reset for use with set_map/get_map. 2755 uint unique_old = _compile->unique(); 2756 2757 // Phase 1: Process possible allocations from alloc_worklist. 2758 // Create instance types for the CheckCastPP for allocations where possible. 2759 // 2760 // (Note: don't forget to change the order of the second AddP node on 2761 // the alloc_worklist if the order of the worklist processing is changed, 2762 // see the comment in find_second_addp().) 2763 // 2764 while (alloc_worklist.length() != 0) { 2765 Node *n = alloc_worklist.pop(); 2766 uint ni = n->_idx; 2767 if (n->is_Call()) { 2768 CallNode *alloc = n->as_Call(); 2769 // copy escape information to call node 2770 PointsToNode* ptn = ptnode_adr(alloc->_idx); 2771 PointsToNode::EscapeState es = ptn->escape_state(); 2772 // We have an allocation or call which returns a Java object, 2773 // see if it is unescaped. 2774 if (es != PointsToNode::NoEscape || !ptn->scalar_replaceable()) 2775 continue; 2776 // Find CheckCastPP for the allocate or for the return value of a call 2777 n = alloc->result_cast(); 2778 if (n == NULL) { // No uses except Initialize node 2779 if (alloc->is_Allocate()) { 2780 // Set the scalar_replaceable flag for allocation 2781 // so it could be eliminated if it has no uses. 2782 alloc->as_Allocate()->_is_scalar_replaceable = true; 2783 } 2784 if (alloc->is_CallStaticJava()) { 2785 // Set the scalar_replaceable flag for boxing method 2786 // so it could be eliminated if it has no uses. 2787 alloc->as_CallStaticJava()->_is_scalar_replaceable = true; 2788 } 2789 continue; 2790 } 2791 if (!n->is_CheckCastPP()) { // not unique CheckCastPP. 2792 assert(!alloc->is_Allocate(), "allocation should have unique type"); 2793 continue; 2794 } 2795 2796 // The inline code for Object.clone() casts the allocation result to 2797 // java.lang.Object and then to the actual type of the allocated 2798 // object. Detect this case and use the second cast. 2799 // Also detect j.l.reflect.Array.newInstance(jobject, jint) case when 2800 // the allocation result is cast to java.lang.Object and then 2801 // to the actual Array type. 2802 if (alloc->is_Allocate() && n->as_Type()->type() == TypeInstPtr::NOTNULL 2803 && (alloc->is_AllocateArray() || 2804 igvn->type(alloc->in(AllocateNode::KlassNode)) != TypeKlassPtr::OBJECT)) { 2805 Node *cast2 = NULL; 2806 for (DUIterator_Fast imax, i = n->fast_outs(imax); i < imax; i++) { 2807 Node *use = n->fast_out(i); 2808 if (use->is_CheckCastPP()) { 2809 cast2 = use; 2810 break; 2811 } 2812 } 2813 if (cast2 != NULL) { 2814 n = cast2; 2815 } else { 2816 // Non-scalar replaceable if the allocation type is unknown statically 2817 // (reflection allocation), the object can't be restored during 2818 // deoptimization without precise type. 2819 continue; 2820 } 2821 } 2822 if (alloc->is_Allocate()) { 2823 // Set the scalar_replaceable flag for allocation 2824 // so it could be eliminated. 2825 alloc->as_Allocate()->_is_scalar_replaceable = true; 2826 } 2827 if (alloc->is_CallStaticJava()) { 2828 // Set the scalar_replaceable flag for boxing method 2829 // so it could be eliminated. 2830 alloc->as_CallStaticJava()->_is_scalar_replaceable = true; 2831 } 2832 set_escape_state(ptnode_adr(n->_idx), es); // CheckCastPP escape state 2833 // in order for an object to be scalar-replaceable, it must be: 2834 // - a direct allocation (not a call returning an object) 2835 // - non-escaping 2836 // - eligible to be a unique type 2837 // - not determined to be ineligible by escape analysis 2838 set_map(alloc, n); 2839 set_map(n, alloc); 2840 const TypeOopPtr *t = igvn->type(n)->isa_oopptr(); 2841 if (t == NULL) 2842 continue; // not a TypeOopPtr 2843 const TypeOopPtr* tinst = t->cast_to_exactness(true)->is_oopptr()->cast_to_instance_id(ni); 2844 igvn->hash_delete(n); 2845 igvn->set_type(n, tinst); 2846 n->raise_bottom_type(tinst); 2847 igvn->hash_insert(n); 2848 record_for_optimizer(n); 2849 if (alloc->is_Allocate() && (t->isa_instptr() || t->isa_aryptr())) { 2850 2851 // First, put on the worklist all Field edges from Connection Graph 2852 // which is more accurate then putting immediate users from Ideal Graph. 2853 for (EdgeIterator e(ptn); e.has_next(); e.next()) { 2854 PointsToNode* tgt = e.get(); 2855 Node* use = tgt->ideal_node(); 2856 assert(tgt->is_Field() && use->is_AddP(), 2857 "only AddP nodes are Field edges in CG"); 2858 if (use->outcnt() > 0) { // Don't process dead nodes 2859 Node* addp2 = find_second_addp(use, use->in(AddPNode::Base)); 2860 if (addp2 != NULL) { 2861 assert(alloc->is_AllocateArray(),"array allocation was expected"); 2862 alloc_worklist.append_if_missing(addp2); 2863 } 2864 alloc_worklist.append_if_missing(use); 2865 } 2866 } 2867 2868 // An allocation may have an Initialize which has raw stores. Scan 2869 // the users of the raw allocation result and push AddP users 2870 // on alloc_worklist. 2871 Node *raw_result = alloc->proj_out(TypeFunc::Parms); 2872 assert (raw_result != NULL, "must have an allocation result"); 2873 for (DUIterator_Fast imax, i = raw_result->fast_outs(imax); i < imax; i++) { 2874 Node *use = raw_result->fast_out(i); 2875 if (use->is_AddP() && use->outcnt() > 0) { // Don't process dead nodes 2876 Node* addp2 = find_second_addp(use, raw_result); 2877 if (addp2 != NULL) { 2878 assert(alloc->is_AllocateArray(),"array allocation was expected"); 2879 alloc_worklist.append_if_missing(addp2); 2880 } 2881 alloc_worklist.append_if_missing(use); 2882 } else if (use->is_MemBar()) { 2883 memnode_worklist.append_if_missing(use); 2884 } 2885 } 2886 } 2887 } else if (n->is_AddP()) { 2888 JavaObjectNode* jobj = unique_java_object(get_addp_base(n)); 2889 if (jobj == NULL || jobj == phantom_obj) { 2890 #ifdef ASSERT 2891 ptnode_adr(get_addp_base(n)->_idx)->dump(); 2892 ptnode_adr(n->_idx)->dump(); 2893 assert(jobj != NULL && jobj != phantom_obj, "escaped allocation"); 2894 #endif 2895 _compile->record_failure(C2Compiler::retry_no_escape_analysis()); 2896 return; 2897 } 2898 Node *base = get_map(jobj->idx()); // CheckCastPP node 2899 if (!split_AddP(n, base)) continue; // wrong type from dead path 2900 } else if (n->is_Phi() || 2901 n->is_CheckCastPP() || 2902 n->is_EncodeP() || 2903 n->is_DecodeN() || 2904 (n->is_ConstraintCast() && n->Opcode() == Op_CastPP)) { 2905 if (visited.test_set(n->_idx)) { 2906 assert(n->is_Phi(), "loops only through Phi's"); 2907 continue; // already processed 2908 } 2909 JavaObjectNode* jobj = unique_java_object(n); 2910 if (jobj == NULL || jobj == phantom_obj) { 2911 #ifdef ASSERT 2912 ptnode_adr(n->_idx)->dump(); 2913 assert(jobj != NULL && jobj != phantom_obj, "escaped allocation"); 2914 #endif 2915 _compile->record_failure(C2Compiler::retry_no_escape_analysis()); 2916 return; 2917 } else { 2918 Node *val = get_map(jobj->idx()); // CheckCastPP node 2919 TypeNode *tn = n->as_Type(); 2920 const TypeOopPtr* tinst = igvn->type(val)->isa_oopptr(); 2921 assert(tinst != NULL && tinst->is_known_instance() && 2922 tinst->instance_id() == jobj->idx() , "instance type expected."); 2923 2924 const Type *tn_type = igvn->type(tn); 2925 const TypeOopPtr *tn_t; 2926 if (tn_type->isa_narrowoop()) { 2927 tn_t = tn_type->make_ptr()->isa_oopptr(); 2928 } else { 2929 tn_t = tn_type->isa_oopptr(); 2930 } 2931 if (tn_t != NULL && tinst->klass()->is_subtype_of(tn_t->klass())) { 2932 if (tn_type->isa_narrowoop()) { 2933 tn_type = tinst->make_narrowoop(); 2934 } else { 2935 tn_type = tinst; 2936 } 2937 igvn->hash_delete(tn); 2938 igvn->set_type(tn, tn_type); 2939 tn->set_type(tn_type); 2940 igvn->hash_insert(tn); 2941 record_for_optimizer(n); 2942 } else { 2943 assert(tn_type == TypePtr::NULL_PTR || 2944 tn_t != NULL && !tinst->klass()->is_subtype_of(tn_t->klass()), 2945 "unexpected type"); 2946 continue; // Skip dead path with different type 2947 } 2948 } 2949 } else { 2950 debug_only(n->dump();) 2951 assert(false, "EA: unexpected node"); 2952 continue; 2953 } 2954 // push allocation's users on appropriate worklist 2955 for (DUIterator_Fast imax, i = n->fast_outs(imax); i < imax; i++) { 2956 Node *use = n->fast_out(i); 2957 if(use->is_Mem() && use->in(MemNode::Address) == n) { 2958 // Load/store to instance's field 2959 memnode_worklist.append_if_missing(use); 2960 } else if (use->is_MemBar()) { 2961 if (use->in(TypeFunc::Memory) == n) { // Ignore precedent edge 2962 memnode_worklist.append_if_missing(use); 2963 } 2964 } else if (use->is_AddP() && use->outcnt() > 0) { // No dead nodes 2965 Node* addp2 = find_second_addp(use, n); 2966 if (addp2 != NULL) { 2967 alloc_worklist.append_if_missing(addp2); 2968 } 2969 alloc_worklist.append_if_missing(use); 2970 } else if (use->is_Phi() || 2971 use->is_CheckCastPP() || 2972 use->is_EncodeNarrowPtr() || 2973 use->is_DecodeNarrowPtr() || 2974 (use->is_ConstraintCast() && use->Opcode() == Op_CastPP)) { 2975 alloc_worklist.append_if_missing(use); 2976 #ifdef ASSERT 2977 } else if (use->is_Mem()) { 2978 assert(use->in(MemNode::Address) != n, "EA: missing allocation reference path"); 2979 } else if (use->is_MergeMem()) { 2980 assert(_mergemem_worklist.contains(use->as_MergeMem()), "EA: missing MergeMem node in the worklist"); 2981 } else if (use->is_SafePoint()) { 2982 // Look for MergeMem nodes for calls which reference unique allocation 2983 // (through CheckCastPP nodes) even for debug info. 2984 Node* m = use->in(TypeFunc::Memory); 2985 if (m->is_MergeMem()) { 2986 assert(_mergemem_worklist.contains(m->as_MergeMem()), "EA: missing MergeMem node in the worklist"); 2987 } 2988 } else if (use->Opcode() == Op_EncodeISOArray) { 2989 if (use->in(MemNode::Memory) == n || use->in(3) == n) { 2990 // EncodeISOArray overwrites destination array 2991 memnode_worklist.append_if_missing(use); 2992 } 2993 } else { 2994 uint op = use->Opcode(); 2995 if (!(op == Op_CmpP || op == Op_Conv2B || 2996 op == Op_CastP2X || op == Op_StoreCM || 2997 op == Op_FastLock || op == Op_AryEq || op == Op_StrComp || 2998 op == Op_StrEquals || op == Op_StrIndexOf)) { 2999 n->dump(); 3000 use->dump(); 3001 assert(false, "EA: missing allocation reference path"); 3002 } 3003 #endif 3004 } 3005 } 3006 3007 } 3008 // New alias types were created in split_AddP(). 3009 uint new_index_end = (uint) _compile->num_alias_types(); 3010 assert(unique_old == _compile->unique(), "there should be no new ideal nodes after Phase 1"); 3011 3012 // Phase 2: Process MemNode's from memnode_worklist. compute new address type and 3013 // compute new values for Memory inputs (the Memory inputs are not 3014 // actually updated until phase 4.) 3015 if (memnode_worklist.length() == 0) 3016 return; // nothing to do 3017 while (memnode_worklist.length() != 0) { 3018 Node *n = memnode_worklist.pop(); 3019 if (visited.test_set(n->_idx)) 3020 continue; 3021 if (n->is_Phi() || n->is_ClearArray()) { 3022 // we don't need to do anything, but the users must be pushed 3023 } else if (n->is_MemBar()) { // Initialize, MemBar nodes 3024 // we don't need to do anything, but the users must be pushed 3025 n = n->as_MemBar()->proj_out(TypeFunc::Memory); 3026 if (n == NULL) 3027 continue; 3028 } else if (n->Opcode() == Op_EncodeISOArray) { 3029 // get the memory projection 3030 for (DUIterator_Fast imax, i = n->fast_outs(imax); i < imax; i++) { 3031 Node *use = n->fast_out(i); 3032 if (use->Opcode() == Op_SCMemProj) { 3033 n = use; 3034 break; 3035 } 3036 } 3037 assert(n->Opcode() == Op_SCMemProj, "memory projection required"); 3038 } else { 3039 assert(n->is_Mem(), "memory node required."); 3040 Node *addr = n->in(MemNode::Address); 3041 const Type *addr_t = igvn->type(addr); 3042 if (addr_t == Type::TOP) 3043 continue; 3044 assert (addr_t->isa_ptr() != NULL, "pointer type required."); 3045 int alias_idx = _compile->get_alias_index(addr_t->is_ptr()); 3046 assert ((uint)alias_idx < new_index_end, "wrong alias index"); 3047 Node *mem = find_inst_mem(n->in(MemNode::Memory), alias_idx, orig_phis); 3048 if (_compile->failing()) { 3049 return; 3050 } 3051 if (mem != n->in(MemNode::Memory)) { 3052 // We delay the memory edge update since we need old one in 3053 // MergeMem code below when instances memory slices are separated. 3054 set_map(n, mem); 3055 } 3056 if (n->is_Load()) { 3057 continue; // don't push users 3058 } else if (n->is_LoadStore()) { 3059 // get the memory projection 3060 for (DUIterator_Fast imax, i = n->fast_outs(imax); i < imax; i++) { 3061 Node *use = n->fast_out(i); 3062 if (use->Opcode() == Op_SCMemProj) { 3063 n = use; 3064 break; 3065 } 3066 } 3067 assert(n->Opcode() == Op_SCMemProj, "memory projection required"); 3068 } 3069 } 3070 // push user on appropriate worklist 3071 for (DUIterator_Fast imax, i = n->fast_outs(imax); i < imax; i++) { 3072 Node *use = n->fast_out(i); 3073 if (use->is_Phi() || use->is_ClearArray()) { 3074 memnode_worklist.append_if_missing(use); 3075 } else if (use->is_Mem() && use->in(MemNode::Memory) == n) { 3076 if (use->Opcode() == Op_StoreCM) // Ignore cardmark stores 3077 continue; 3078 memnode_worklist.append_if_missing(use); 3079 } else if (use->is_MemBar()) { 3080 if (use->in(TypeFunc::Memory) == n) { // Ignore precedent edge 3081 memnode_worklist.append_if_missing(use); 3082 } 3083 #ifdef ASSERT 3084 } else if(use->is_Mem()) { 3085 assert(use->in(MemNode::Memory) != n, "EA: missing memory path"); 3086 } else if (use->is_MergeMem()) { 3087 assert(_mergemem_worklist.contains(use->as_MergeMem()), "EA: missing MergeMem node in the worklist"); 3088 } else if (use->Opcode() == Op_EncodeISOArray) { 3089 if (use->in(MemNode::Memory) == n || use->in(3) == n) { 3090 // EncodeISOArray overwrites destination array 3091 memnode_worklist.append_if_missing(use); 3092 } 3093 } else { 3094 uint op = use->Opcode(); 3095 if (!(op == Op_StoreCM || 3096 (op == Op_CallLeaf && use->as_CallLeaf()->_name != NULL && 3097 strcmp(use->as_CallLeaf()->_name, "g1_wb_pre") == 0) || 3098 op == Op_AryEq || op == Op_StrComp || 3099 op == Op_StrEquals || op == Op_StrIndexOf)) { 3100 n->dump(); 3101 use->dump(); 3102 assert(false, "EA: missing memory path"); 3103 } 3104 #endif 3105 } 3106 } 3107 } 3108 3109 // Phase 3: Process MergeMem nodes from mergemem_worklist. 3110 // Walk each memory slice moving the first node encountered of each 3111 // instance type to the the input corresponding to its alias index. 3112 uint length = _mergemem_worklist.length(); 3113 for( uint next = 0; next < length; ++next ) { 3114 MergeMemNode* nmm = _mergemem_worklist.at(next); 3115 assert(!visited.test_set(nmm->_idx), "should not be visited before"); 3116 // Note: we don't want to use MergeMemStream here because we only want to 3117 // scan inputs which exist at the start, not ones we add during processing. 3118 // Note 2: MergeMem may already contains instance memory slices added 3119 // during find_inst_mem() call when memory nodes were processed above. 3120 igvn->hash_delete(nmm); 3121 uint nslices = nmm->req(); 3122 for (uint i = Compile::AliasIdxRaw+1; i < nslices; i++) { 3123 Node* mem = nmm->in(i); 3124 Node* cur = NULL; 3125 if (mem == NULL || mem->is_top()) 3126 continue; 3127 // First, update mergemem by moving memory nodes to corresponding slices 3128 // if their type became more precise since this mergemem was created. 3129 while (mem->is_Mem()) { 3130 const Type *at = igvn->type(mem->in(MemNode::Address)); 3131 if (at != Type::TOP) { 3132 assert (at->isa_ptr() != NULL, "pointer type required."); 3133 uint idx = (uint)_compile->get_alias_index(at->is_ptr()); 3134 if (idx == i) { 3135 if (cur == NULL) 3136 cur = mem; 3137 } else { 3138 if (idx >= nmm->req() || nmm->is_empty_memory(nmm->in(idx))) { 3139 nmm->set_memory_at(idx, mem); 3140 } 3141 } 3142 } 3143 mem = mem->in(MemNode::Memory); 3144 } 3145 nmm->set_memory_at(i, (cur != NULL) ? cur : mem); 3146 // Find any instance of the current type if we haven't encountered 3147 // already a memory slice of the instance along the memory chain. 3148 for (uint ni = new_index_start; ni < new_index_end; ni++) { 3149 if((uint)_compile->get_general_index(ni) == i) { 3150 Node *m = (ni >= nmm->req()) ? nmm->empty_memory() : nmm->in(ni); 3151 if (nmm->is_empty_memory(m)) { 3152 Node* result = find_inst_mem(mem, ni, orig_phis); 3153 if (_compile->failing()) { 3154 return; 3155 } 3156 nmm->set_memory_at(ni, result); 3157 } 3158 } 3159 } 3160 } 3161 // Find the rest of instances values 3162 for (uint ni = new_index_start; ni < new_index_end; ni++) { 3163 const TypeOopPtr *tinst = _compile->get_adr_type(ni)->isa_oopptr(); 3164 Node* result = step_through_mergemem(nmm, ni, tinst); 3165 if (result == nmm->base_memory()) { 3166 // Didn't find instance memory, search through general slice recursively. 3167 result = nmm->memory_at(_compile->get_general_index(ni)); 3168 result = find_inst_mem(result, ni, orig_phis); 3169 if (_compile->failing()) { 3170 return; 3171 } 3172 nmm->set_memory_at(ni, result); 3173 } 3174 } 3175 igvn->hash_insert(nmm); 3176 record_for_optimizer(nmm); 3177 } 3178 3179 // Phase 4: Update the inputs of non-instance memory Phis and 3180 // the Memory input of memnodes 3181 // First update the inputs of any non-instance Phi's from 3182 // which we split out an instance Phi. Note we don't have 3183 // to recursively process Phi's encounted on the input memory 3184 // chains as is done in split_memory_phi() since they will 3185 // also be processed here. 3186 for (int j = 0; j < orig_phis.length(); j++) { 3187 PhiNode *phi = orig_phis.at(j); 3188 int alias_idx = _compile->get_alias_index(phi->adr_type()); 3189 igvn->hash_delete(phi); 3190 for (uint i = 1; i < phi->req(); i++) { 3191 Node *mem = phi->in(i); 3192 Node *new_mem = find_inst_mem(mem, alias_idx, orig_phis); 3193 if (_compile->failing()) { 3194 return; 3195 } 3196 if (mem != new_mem) { 3197 phi->set_req(i, new_mem); 3198 } 3199 } 3200 igvn->hash_insert(phi); 3201 record_for_optimizer(phi); 3202 } 3203 3204 // Update the memory inputs of MemNodes with the value we computed 3205 // in Phase 2 and move stores memory users to corresponding memory slices. 3206 // Disable memory split verification code until the fix for 6984348. 3207 // Currently it produces false negative results since it does not cover all cases. 3208 #if 0 // ifdef ASSERT 3209 visited.Reset(); 3210 Node_Stack old_mems(arena, _compile->unique() >> 2); 3211 #endif 3212 for (uint i = 0; i < ideal_nodes.size(); i++) { 3213 Node* n = ideal_nodes.at(i); 3214 Node* nmem = get_map(n->_idx); 3215 assert(nmem != NULL, "sanity"); 3216 if (n->is_Mem()) { 3217 #if 0 // ifdef ASSERT 3218 Node* old_mem = n->in(MemNode::Memory); 3219 if (!visited.test_set(old_mem->_idx)) { 3220 old_mems.push(old_mem, old_mem->outcnt()); 3221 } 3222 #endif 3223 assert(n->in(MemNode::Memory) != nmem, "sanity"); 3224 if (!n->is_Load()) { 3225 // Move memory users of a store first. 3226 move_inst_mem(n, orig_phis); 3227 } 3228 // Now update memory input 3229 igvn->hash_delete(n); 3230 n->set_req(MemNode::Memory, nmem); 3231 igvn->hash_insert(n); 3232 record_for_optimizer(n); 3233 } else { 3234 assert(n->is_Allocate() || n->is_CheckCastPP() || 3235 n->is_AddP() || n->is_Phi(), "unknown node used for set_map()"); 3236 } 3237 } 3238 #if 0 // ifdef ASSERT 3239 // Verify that memory was split correctly 3240 while (old_mems.is_nonempty()) { 3241 Node* old_mem = old_mems.node(); 3242 uint old_cnt = old_mems.index(); 3243 old_mems.pop(); 3244 assert(old_cnt == old_mem->outcnt(), "old mem could be lost"); 3245 } 3246 #endif 3247 } 3248 3249 #ifndef PRODUCT 3250 static const char *node_type_names[] = { 3251 "UnknownType", 3252 "JavaObject", 3253 "LocalVar", 3254 "Field", 3255 "Arraycopy" 3256 }; 3257 3258 static const char *esc_names[] = { 3259 "UnknownEscape", 3260 "NoEscape", 3261 "ArgEscape", 3262 "GlobalEscape" 3263 }; 3264 3265 void PointsToNode::dump(bool print_state) const { 3266 NodeType nt = node_type(); 3267 tty->print("%s ", node_type_names[(int) nt]); 3268 if (print_state) { 3269 EscapeState es = escape_state(); 3270 EscapeState fields_es = fields_escape_state(); 3271 tty->print("%s(%s) ", esc_names[(int)es], esc_names[(int)fields_es]); 3272 if (nt == PointsToNode::JavaObject && !this->scalar_replaceable()) 3273 tty->print("NSR "); 3274 } 3275 if (is_Field()) { 3276 FieldNode* f = (FieldNode*)this; 3277 if (f->is_oop()) 3278 tty->print("oop "); 3279 if (f->offset() > 0) 3280 tty->print("+%d ", f->offset()); 3281 tty->print("("); 3282 for (BaseIterator i(f); i.has_next(); i.next()) { 3283 PointsToNode* b = i.get(); 3284 tty->print(" %d%s", b->idx(),(b->is_JavaObject() ? "P" : "")); 3285 } 3286 tty->print(" )"); 3287 } 3288 tty->print("["); 3289 for (EdgeIterator i(this); i.has_next(); i.next()) { 3290 PointsToNode* e = i.get(); 3291 tty->print(" %d%s%s", e->idx(),(e->is_JavaObject() ? "P" : (e->is_Field() ? "F" : "")), e->is_Arraycopy() ? "cp" : ""); 3292 } 3293 tty->print(" ["); 3294 for (UseIterator i(this); i.has_next(); i.next()) { 3295 PointsToNode* u = i.get(); 3296 bool is_base = false; 3297 if (PointsToNode::is_base_use(u)) { 3298 is_base = true; 3299 u = PointsToNode::get_use_node(u)->as_Field(); 3300 } 3301 tty->print(" %d%s%s", u->idx(), is_base ? "b" : "", u->is_Arraycopy() ? "cp" : ""); 3302 } 3303 tty->print(" ]] "); 3304 if (_node == NULL) 3305 tty->print_cr("<null>"); 3306 else 3307 _node->dump(); 3308 } 3309 3310 void ConnectionGraph::dump(GrowableArray<PointsToNode*>& ptnodes_worklist) { 3311 bool first = true; 3312 int ptnodes_length = ptnodes_worklist.length(); 3313 for (int i = 0; i < ptnodes_length; i++) { 3314 PointsToNode *ptn = ptnodes_worklist.at(i); 3315 if (ptn == NULL || !ptn->is_JavaObject()) 3316 continue; 3317 PointsToNode::EscapeState es = ptn->escape_state(); 3318 if ((es != PointsToNode::NoEscape) && !Verbose) { 3319 continue; 3320 } 3321 Node* n = ptn->ideal_node(); 3322 if (n->is_Allocate() || (n->is_CallStaticJava() && 3323 n->as_CallStaticJava()->is_boxing_method())) { 3324 if (first) { 3325 tty->cr(); 3326 tty->print("======== Connection graph for "); 3327 _compile->method()->print_short_name(); 3328 tty->cr(); 3329 first = false; 3330 } 3331 ptn->dump(); 3332 // Print all locals and fields which reference this allocation 3333 for (UseIterator j(ptn); j.has_next(); j.next()) { 3334 PointsToNode* use = j.get(); 3335 if (use->is_LocalVar()) { 3336 use->dump(Verbose); 3337 } else if (Verbose) { 3338 use->dump(); 3339 } 3340 } 3341 tty->cr(); 3342 } 3343 } 3344 } 3345 #endif