escape.cpp revision 293:c3e045194476
1/* 2 * Copyright 2005-2008 Sun Microsystems, Inc. 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 Sun Microsystems, Inc., 4150 Network Circle, Santa Clara, 20 * CA 95054 USA or visit www.sun.com if you need additional information or 21 * have any questions. 22 * 23 */ 24 25#include "incls/_precompiled.incl" 26#include "incls/_escape.cpp.incl" 27 28void PointsToNode::add_edge(uint targIdx, PointsToNode::EdgeType et) { 29 uint v = (targIdx << EdgeShift) + ((uint) et); 30 if (_edges == NULL) { 31 Arena *a = Compile::current()->comp_arena(); 32 _edges = new(a) GrowableArray<uint>(a, INITIAL_EDGE_COUNT, 0, 0); 33 } 34 _edges->append_if_missing(v); 35} 36 37void PointsToNode::remove_edge(uint targIdx, PointsToNode::EdgeType et) { 38 uint v = (targIdx << EdgeShift) + ((uint) et); 39 40 _edges->remove(v); 41} 42 43#ifndef PRODUCT 44static const char *node_type_names[] = { 45 "UnknownType", 46 "JavaObject", 47 "LocalVar", 48 "Field" 49}; 50 51static const char *esc_names[] = { 52 "UnknownEscape", 53 "NoEscape", 54 "ArgEscape", 55 "GlobalEscape" 56}; 57 58static const char *edge_type_suffix[] = { 59 "?", // UnknownEdge 60 "P", // PointsToEdge 61 "D", // DeferredEdge 62 "F" // FieldEdge 63}; 64 65void PointsToNode::dump(bool print_state) const { 66 NodeType nt = node_type(); 67 tty->print("%s ", node_type_names[(int) nt]); 68 if (print_state) { 69 EscapeState es = escape_state(); 70 tty->print("%s %s ", esc_names[(int) es], _scalar_replaceable ? "":"NSR"); 71 } 72 tty->print("[["); 73 for (uint i = 0; i < edge_count(); i++) { 74 tty->print(" %d%s", edge_target(i), edge_type_suffix[(int) edge_type(i)]); 75 } 76 tty->print("]] "); 77 if (_node == NULL) 78 tty->print_cr("<null>"); 79 else 80 _node->dump(); 81} 82#endif 83 84ConnectionGraph::ConnectionGraph(Compile * C) : 85 _nodes(C->comp_arena(), C->unique(), C->unique(), PointsToNode()), 86 _processed(C->comp_arena()), 87 _collecting(true), 88 _compile(C), 89 _node_map(C->comp_arena()) { 90 91 _phantom_object = C->top()->_idx, 92 add_node(C->top(), PointsToNode::JavaObject, PointsToNode::GlobalEscape,true); 93 94 // Add ConP(#NULL) and ConN(#NULL) nodes. 95 PhaseGVN* igvn = C->initial_gvn(); 96 Node* oop_null = igvn->zerocon(T_OBJECT); 97 _oop_null = oop_null->_idx; 98 assert(_oop_null < C->unique(), "should be created already"); 99 add_node(oop_null, PointsToNode::JavaObject, PointsToNode::NoEscape, true); 100 101 if (UseCompressedOops) { 102 Node* noop_null = igvn->zerocon(T_NARROWOOP); 103 _noop_null = noop_null->_idx; 104 assert(_noop_null < C->unique(), "should be created already"); 105 add_node(noop_null, PointsToNode::JavaObject, PointsToNode::NoEscape, true); 106 } 107} 108 109void ConnectionGraph::add_pointsto_edge(uint from_i, uint to_i) { 110 PointsToNode *f = ptnode_adr(from_i); 111 PointsToNode *t = ptnode_adr(to_i); 112 113 assert(f->node_type() != PointsToNode::UnknownType && t->node_type() != PointsToNode::UnknownType, "node types must be set"); 114 assert(f->node_type() == PointsToNode::LocalVar || f->node_type() == PointsToNode::Field, "invalid source of PointsTo edge"); 115 assert(t->node_type() == PointsToNode::JavaObject, "invalid destination of PointsTo edge"); 116 f->add_edge(to_i, PointsToNode::PointsToEdge); 117} 118 119void ConnectionGraph::add_deferred_edge(uint from_i, uint to_i) { 120 PointsToNode *f = ptnode_adr(from_i); 121 PointsToNode *t = ptnode_adr(to_i); 122 123 assert(f->node_type() != PointsToNode::UnknownType && t->node_type() != PointsToNode::UnknownType, "node types must be set"); 124 assert(f->node_type() == PointsToNode::LocalVar || f->node_type() == PointsToNode::Field, "invalid source of Deferred edge"); 125 assert(t->node_type() == PointsToNode::LocalVar || t->node_type() == PointsToNode::Field, "invalid destination of Deferred edge"); 126 // don't add a self-referential edge, this can occur during removal of 127 // deferred edges 128 if (from_i != to_i) 129 f->add_edge(to_i, PointsToNode::DeferredEdge); 130} 131 132int ConnectionGraph::address_offset(Node* adr, PhaseTransform *phase) { 133 const Type *adr_type = phase->type(adr); 134 if (adr->is_AddP() && adr_type->isa_oopptr() == NULL && 135 adr->in(AddPNode::Address)->is_Proj() && 136 adr->in(AddPNode::Address)->in(0)->is_Allocate()) { 137 // We are computing a raw address for a store captured by an Initialize 138 // compute an appropriate address type. AddP cases #3 and #5 (see below). 139 int offs = (int)phase->find_intptr_t_con(adr->in(AddPNode::Offset), Type::OffsetBot); 140 assert(offs != Type::OffsetBot || 141 adr->in(AddPNode::Address)->in(0)->is_AllocateArray(), 142 "offset must be a constant or it is initialization of array"); 143 return offs; 144 } 145 const TypePtr *t_ptr = adr_type->isa_ptr(); 146 assert(t_ptr != NULL, "must be a pointer type"); 147 return t_ptr->offset(); 148} 149 150void ConnectionGraph::add_field_edge(uint from_i, uint to_i, int offset) { 151 PointsToNode *f = ptnode_adr(from_i); 152 PointsToNode *t = ptnode_adr(to_i); 153 154 assert(f->node_type() != PointsToNode::UnknownType && t->node_type() != PointsToNode::UnknownType, "node types must be set"); 155 assert(f->node_type() == PointsToNode::JavaObject, "invalid destination of Field edge"); 156 assert(t->node_type() == PointsToNode::Field, "invalid destination of Field edge"); 157 assert (t->offset() == -1 || t->offset() == offset, "conflicting field offsets"); 158 t->set_offset(offset); 159 160 f->add_edge(to_i, PointsToNode::FieldEdge); 161} 162 163void ConnectionGraph::set_escape_state(uint ni, PointsToNode::EscapeState es) { 164 PointsToNode *npt = ptnode_adr(ni); 165 PointsToNode::EscapeState old_es = npt->escape_state(); 166 if (es > old_es) 167 npt->set_escape_state(es); 168} 169 170void ConnectionGraph::add_node(Node *n, PointsToNode::NodeType nt, 171 PointsToNode::EscapeState es, bool done) { 172 PointsToNode* ptadr = ptnode_adr(n->_idx); 173 ptadr->_node = n; 174 ptadr->set_node_type(nt); 175 176 // inline set_escape_state(idx, es); 177 PointsToNode::EscapeState old_es = ptadr->escape_state(); 178 if (es > old_es) 179 ptadr->set_escape_state(es); 180 181 if (done) 182 _processed.set(n->_idx); 183} 184 185PointsToNode::EscapeState ConnectionGraph::escape_state(Node *n, PhaseTransform *phase) { 186 uint idx = n->_idx; 187 PointsToNode::EscapeState es; 188 189 // If we are still collecting or there were no non-escaping allocations 190 // we don't know the answer yet 191 if (_collecting) 192 return PointsToNode::UnknownEscape; 193 194 // if the node was created after the escape computation, return 195 // UnknownEscape 196 if (idx >= nodes_size()) 197 return PointsToNode::UnknownEscape; 198 199 es = ptnode_adr(idx)->escape_state(); 200 201 // if we have already computed a value, return it 202 if (es != PointsToNode::UnknownEscape) 203 return es; 204 205 // PointsTo() calls n->uncast() which can return a new ideal node. 206 if (n->uncast()->_idx >= nodes_size()) 207 return PointsToNode::UnknownEscape; 208 209 // compute max escape state of anything this node could point to 210 VectorSet ptset(Thread::current()->resource_area()); 211 PointsTo(ptset, n, phase); 212 for(VectorSetI i(&ptset); i.test() && es != PointsToNode::GlobalEscape; ++i) { 213 uint pt = i.elem; 214 PointsToNode::EscapeState pes = ptnode_adr(pt)->escape_state(); 215 if (pes > es) 216 es = pes; 217 } 218 // cache the computed escape state 219 assert(es != PointsToNode::UnknownEscape, "should have computed an escape state"); 220 ptnode_adr(idx)->set_escape_state(es); 221 return es; 222} 223 224void ConnectionGraph::PointsTo(VectorSet &ptset, Node * n, PhaseTransform *phase) { 225 VectorSet visited(Thread::current()->resource_area()); 226 GrowableArray<uint> worklist; 227 228#ifdef ASSERT 229 Node *orig_n = n; 230#endif 231 232 n = n->uncast(); 233 PointsToNode* npt = ptnode_adr(n->_idx); 234 235 // If we have a JavaObject, return just that object 236 if (npt->node_type() == PointsToNode::JavaObject) { 237 ptset.set(n->_idx); 238 return; 239 } 240#ifdef ASSERT 241 if (npt->_node == NULL) { 242 if (orig_n != n) 243 orig_n->dump(); 244 n->dump(); 245 assert(npt->_node != NULL, "unregistered node"); 246 } 247#endif 248 worklist.push(n->_idx); 249 while(worklist.length() > 0) { 250 int ni = worklist.pop(); 251 if (visited.test_set(ni)) 252 continue; 253 254 PointsToNode* pn = ptnode_adr(ni); 255 // ensure that all inputs of a Phi have been processed 256 assert(!_collecting || !pn->_node->is_Phi() || _processed.test(ni),""); 257 258 int edges_processed = 0; 259 uint e_cnt = pn->edge_count(); 260 for (uint e = 0; e < e_cnt; e++) { 261 uint etgt = pn->edge_target(e); 262 PointsToNode::EdgeType et = pn->edge_type(e); 263 if (et == PointsToNode::PointsToEdge) { 264 ptset.set(etgt); 265 edges_processed++; 266 } else if (et == PointsToNode::DeferredEdge) { 267 worklist.push(etgt); 268 edges_processed++; 269 } else { 270 assert(false,"neither PointsToEdge or DeferredEdge"); 271 } 272 } 273 if (edges_processed == 0) { 274 // no deferred or pointsto edges found. Assume the value was set 275 // outside this method. Add the phantom object to the pointsto set. 276 ptset.set(_phantom_object); 277 } 278 } 279} 280 281void ConnectionGraph::remove_deferred(uint ni, GrowableArray<uint>* deferred_edges, VectorSet* visited) { 282 // This method is most expensive during ConnectionGraph construction. 283 // Reuse vectorSet and an additional growable array for deferred edges. 284 deferred_edges->clear(); 285 visited->Clear(); 286 287 visited->set(ni); 288 PointsToNode *ptn = ptnode_adr(ni); 289 290 // Mark current edges as visited and move deferred edges to separate array. 291 for (uint i = 0; i < ptn->edge_count(); ) { 292 uint t = ptn->edge_target(i); 293#ifdef ASSERT 294 assert(!visited->test_set(t), "expecting no duplications"); 295#else 296 visited->set(t); 297#endif 298 if (ptn->edge_type(i) == PointsToNode::DeferredEdge) { 299 ptn->remove_edge(t, PointsToNode::DeferredEdge); 300 deferred_edges->append(t); 301 } else { 302 i++; 303 } 304 } 305 for (int next = 0; next < deferred_edges->length(); ++next) { 306 uint t = deferred_edges->at(next); 307 PointsToNode *ptt = ptnode_adr(t); 308 uint e_cnt = ptt->edge_count(); 309 for (uint e = 0; e < e_cnt; e++) { 310 uint etgt = ptt->edge_target(e); 311 if (visited->test_set(etgt)) 312 continue; 313 314 PointsToNode::EdgeType et = ptt->edge_type(e); 315 if (et == PointsToNode::PointsToEdge) { 316 add_pointsto_edge(ni, etgt); 317 if(etgt == _phantom_object) { 318 // Special case - field set outside (globally escaping). 319 ptn->set_escape_state(PointsToNode::GlobalEscape); 320 } 321 } else if (et == PointsToNode::DeferredEdge) { 322 deferred_edges->append(etgt); 323 } else { 324 assert(false,"invalid connection graph"); 325 } 326 } 327 } 328} 329 330 331// Add an edge to node given by "to_i" from any field of adr_i whose offset 332// matches "offset" A deferred edge is added if to_i is a LocalVar, and 333// a pointsto edge is added if it is a JavaObject 334 335void ConnectionGraph::add_edge_from_fields(uint adr_i, uint to_i, int offs) { 336 PointsToNode* an = ptnode_adr(adr_i); 337 PointsToNode* to = ptnode_adr(to_i); 338 bool deferred = (to->node_type() == PointsToNode::LocalVar); 339 340 for (uint fe = 0; fe < an->edge_count(); fe++) { 341 assert(an->edge_type(fe) == PointsToNode::FieldEdge, "expecting a field edge"); 342 int fi = an->edge_target(fe); 343 PointsToNode* pf = ptnode_adr(fi); 344 int po = pf->offset(); 345 if (po == offs || po == Type::OffsetBot || offs == Type::OffsetBot) { 346 if (deferred) 347 add_deferred_edge(fi, to_i); 348 else 349 add_pointsto_edge(fi, to_i); 350 } 351 } 352} 353 354// Add a deferred edge from node given by "from_i" to any field of adr_i 355// whose offset matches "offset". 356void ConnectionGraph::add_deferred_edge_to_fields(uint from_i, uint adr_i, int offs) { 357 PointsToNode* an = ptnode_adr(adr_i); 358 for (uint fe = 0; fe < an->edge_count(); fe++) { 359 assert(an->edge_type(fe) == PointsToNode::FieldEdge, "expecting a field edge"); 360 int fi = an->edge_target(fe); 361 PointsToNode* pf = ptnode_adr(fi); 362 int po = pf->offset(); 363 if (pf->edge_count() == 0) { 364 // we have not seen any stores to this field, assume it was set outside this method 365 add_pointsto_edge(fi, _phantom_object); 366 } 367 if (po == offs || po == Type::OffsetBot || offs == Type::OffsetBot) { 368 add_deferred_edge(from_i, fi); 369 } 370 } 371} 372 373// Helper functions 374 375static Node* get_addp_base(Node *addp) { 376 assert(addp->is_AddP(), "must be AddP"); 377 // 378 // AddP cases for Base and Address inputs: 379 // case #1. Direct object's field reference: 380 // Allocate 381 // | 382 // Proj #5 ( oop result ) 383 // | 384 // CheckCastPP (cast to instance type) 385 // | | 386 // AddP ( base == address ) 387 // 388 // case #2. Indirect object's field reference: 389 // Phi 390 // | 391 // CastPP (cast to instance type) 392 // | | 393 // AddP ( base == address ) 394 // 395 // case #3. Raw object's field reference for Initialize node: 396 // Allocate 397 // | 398 // Proj #5 ( oop result ) 399 // top | 400 // \ | 401 // AddP ( base == top ) 402 // 403 // case #4. Array's element reference: 404 // {CheckCastPP | CastPP} 405 // | | | 406 // | AddP ( array's element offset ) 407 // | | 408 // AddP ( array's offset ) 409 // 410 // case #5. Raw object's field reference for arraycopy stub call: 411 // The inline_native_clone() case when the arraycopy stub is called 412 // after the allocation before Initialize and CheckCastPP nodes. 413 // Allocate 414 // | 415 // Proj #5 ( oop result ) 416 // | | 417 // AddP ( base == address ) 418 // 419 // case #6. Constant Pool, ThreadLocal, CastX2P or 420 // Raw object's field reference: 421 // {ConP, ThreadLocal, CastX2P, raw Load} 422 // top | 423 // \ | 424 // AddP ( base == top ) 425 // 426 // case #7. Klass's field reference. 427 // LoadKlass 428 // | | 429 // AddP ( base == address ) 430 // 431 // case #8. narrow Klass's field reference. 432 // LoadNKlass 433 // | 434 // DecodeN 435 // | | 436 // AddP ( base == address ) 437 // 438 Node *base = addp->in(AddPNode::Base)->uncast(); 439 if (base->is_top()) { // The AddP case #3 and #6. 440 base = addp->in(AddPNode::Address)->uncast(); 441 assert(base->Opcode() == Op_ConP || base->Opcode() == Op_ThreadLocal || 442 base->Opcode() == Op_CastX2P || base->is_DecodeN() || 443 (base->is_Mem() && base->bottom_type() == TypeRawPtr::NOTNULL) || 444 (base->is_Proj() && base->in(0)->is_Allocate()), "sanity"); 445 } 446 return base; 447} 448 449static Node* find_second_addp(Node* addp, Node* n) { 450 assert(addp->is_AddP() && addp->outcnt() > 0, "Don't process dead nodes"); 451 452 Node* addp2 = addp->raw_out(0); 453 if (addp->outcnt() == 1 && addp2->is_AddP() && 454 addp2->in(AddPNode::Base) == n && 455 addp2->in(AddPNode::Address) == addp) { 456 457 assert(addp->in(AddPNode::Base) == n, "expecting the same base"); 458 // 459 // Find array's offset to push it on worklist first and 460 // as result process an array's element offset first (pushed second) 461 // to avoid CastPP for the array's offset. 462 // Otherwise the inserted CastPP (LocalVar) will point to what 463 // the AddP (Field) points to. Which would be wrong since 464 // the algorithm expects the CastPP has the same point as 465 // as AddP's base CheckCastPP (LocalVar). 466 // 467 // ArrayAllocation 468 // | 469 // CheckCastPP 470 // | 471 // memProj (from ArrayAllocation CheckCastPP) 472 // | || 473 // | || Int (element index) 474 // | || | ConI (log(element size)) 475 // | || | / 476 // | || LShift 477 // | || / 478 // | AddP (array's element offset) 479 // | | 480 // | | ConI (array's offset: #12(32-bits) or #24(64-bits)) 481 // | / / 482 // AddP (array's offset) 483 // | 484 // Load/Store (memory operation on array's element) 485 // 486 return addp2; 487 } 488 return NULL; 489} 490 491// 492// Adjust the type and inputs of an AddP which computes the 493// address of a field of an instance 494// 495bool ConnectionGraph::split_AddP(Node *addp, Node *base, PhaseGVN *igvn) { 496 const TypeOopPtr *base_t = igvn->type(base)->isa_oopptr(); 497 assert(base_t != NULL && base_t->is_known_instance(), "expecting instance oopptr"); 498 const TypeOopPtr *t = igvn->type(addp)->isa_oopptr(); 499 if (t == NULL) { 500 // We are computing a raw address for a store captured by an Initialize 501 // compute an appropriate address type (cases #3 and #5). 502 assert(igvn->type(addp) == TypeRawPtr::NOTNULL, "must be raw pointer"); 503 assert(addp->in(AddPNode::Address)->is_Proj(), "base of raw address must be result projection from allocation"); 504 int offs = (int)igvn->find_intptr_t_con(addp->in(AddPNode::Offset), Type::OffsetBot); 505 assert(offs != Type::OffsetBot, "offset must be a constant"); 506 t = base_t->add_offset(offs)->is_oopptr(); 507 } 508 int inst_id = base_t->instance_id(); 509 assert(!t->is_known_instance() || t->instance_id() == inst_id, 510 "old type must be non-instance or match new type"); 511 512 // The type 't' could be subclass of 'base_t'. 513 // As result t->offset() could be large then base_t's size and it will 514 // cause the failure in add_offset() with narrow oops since TypeOopPtr() 515 // constructor verifies correctness of the offset. 516 // 517 // It could happend on subclass's branch (from the type profiling 518 // inlining) which was not eliminated during parsing since the exactness 519 // of the allocation type was not propagated to the subclass type check. 520 // 521 // Do nothing for such AddP node and don't process its users since 522 // this code branch will go away. 523 // 524 if (!t->is_known_instance() && 525 !t->klass()->equals(base_t->klass()) && 526 t->klass()->is_subtype_of(base_t->klass())) { 527 return false; // bail out 528 } 529 530 const TypeOopPtr *tinst = base_t->add_offset(t->offset())->is_oopptr(); 531 // Do NOT remove the next call: ensure an new alias index is allocated 532 // for the instance type 533 int alias_idx = _compile->get_alias_index(tinst); 534 igvn->set_type(addp, tinst); 535 // record the allocation in the node map 536 set_map(addp->_idx, get_map(base->_idx)); 537 538 // Set addp's Base and Address to 'base'. 539 Node *abase = addp->in(AddPNode::Base); 540 Node *adr = addp->in(AddPNode::Address); 541 if (adr->is_Proj() && adr->in(0)->is_Allocate() && 542 adr->in(0)->_idx == (uint)inst_id) { 543 // Skip AddP cases #3 and #5. 544 } else { 545 assert(!abase->is_top(), "sanity"); // AddP case #3 546 if (abase != base) { 547 igvn->hash_delete(addp); 548 addp->set_req(AddPNode::Base, base); 549 if (abase == adr) { 550 addp->set_req(AddPNode::Address, base); 551 } else { 552 // AddP case #4 (adr is array's element offset AddP node) 553#ifdef ASSERT 554 const TypeOopPtr *atype = igvn->type(adr)->isa_oopptr(); 555 assert(adr->is_AddP() && atype != NULL && 556 atype->instance_id() == inst_id, "array's element offset should be processed first"); 557#endif 558 } 559 igvn->hash_insert(addp); 560 } 561 } 562 // Put on IGVN worklist since at least addp's type was changed above. 563 record_for_optimizer(addp); 564 return true; 565} 566 567// 568// Create a new version of orig_phi if necessary. Returns either the newly 569// created phi or an existing phi. Sets create_new to indicate wheter a new 570// phi was created. Cache the last newly created phi in the node map. 571// 572PhiNode *ConnectionGraph::create_split_phi(PhiNode *orig_phi, int alias_idx, GrowableArray<PhiNode *> &orig_phi_worklist, PhaseGVN *igvn, bool &new_created) { 573 Compile *C = _compile; 574 new_created = false; 575 int phi_alias_idx = C->get_alias_index(orig_phi->adr_type()); 576 // nothing to do if orig_phi is bottom memory or matches alias_idx 577 if (phi_alias_idx == alias_idx) { 578 return orig_phi; 579 } 580 // have we already created a Phi for this alias index? 581 PhiNode *result = get_map_phi(orig_phi->_idx); 582 if (result != NULL && C->get_alias_index(result->adr_type()) == alias_idx) { 583 return result; 584 } 585 if ((int)C->unique() + 2*NodeLimitFudgeFactor > MaxNodeLimit) { 586 if (C->do_escape_analysis() == true && !C->failing()) { 587 // Retry compilation without escape analysis. 588 // If this is the first failure, the sentinel string will "stick" 589 // to the Compile object, and the C2Compiler will see it and retry. 590 C->record_failure(C2Compiler::retry_no_escape_analysis()); 591 } 592 return NULL; 593 } 594 orig_phi_worklist.append_if_missing(orig_phi); 595 const TypePtr *atype = C->get_adr_type(alias_idx); 596 result = PhiNode::make(orig_phi->in(0), NULL, Type::MEMORY, atype); 597 set_map_phi(orig_phi->_idx, result); 598 igvn->set_type(result, result->bottom_type()); 599 record_for_optimizer(result); 600 new_created = true; 601 return result; 602} 603 604// 605// Return a new version of Memory Phi "orig_phi" with the inputs having the 606// specified alias index. 607// 608PhiNode *ConnectionGraph::split_memory_phi(PhiNode *orig_phi, int alias_idx, GrowableArray<PhiNode *> &orig_phi_worklist, PhaseGVN *igvn) { 609 610 assert(alias_idx != Compile::AliasIdxBot, "can't split out bottom memory"); 611 Compile *C = _compile; 612 bool new_phi_created; 613 PhiNode *result = create_split_phi(orig_phi, alias_idx, orig_phi_worklist, igvn, new_phi_created); 614 if (!new_phi_created) { 615 return result; 616 } 617 618 GrowableArray<PhiNode *> phi_list; 619 GrowableArray<uint> cur_input; 620 621 PhiNode *phi = orig_phi; 622 uint idx = 1; 623 bool finished = false; 624 while(!finished) { 625 while (idx < phi->req()) { 626 Node *mem = find_inst_mem(phi->in(idx), alias_idx, orig_phi_worklist, igvn); 627 if (mem != NULL && mem->is_Phi()) { 628 PhiNode *newphi = create_split_phi(mem->as_Phi(), alias_idx, orig_phi_worklist, igvn, new_phi_created); 629 if (new_phi_created) { 630 // found an phi for which we created a new split, push current one on worklist and begin 631 // processing new one 632 phi_list.push(phi); 633 cur_input.push(idx); 634 phi = mem->as_Phi(); 635 result = newphi; 636 idx = 1; 637 continue; 638 } else { 639 mem = newphi; 640 } 641 } 642 if (C->failing()) { 643 return NULL; 644 } 645 result->set_req(idx++, mem); 646 } 647#ifdef ASSERT 648 // verify that the new Phi has an input for each input of the original 649 assert( phi->req() == result->req(), "must have same number of inputs."); 650 assert( result->in(0) != NULL && result->in(0) == phi->in(0), "regions must match"); 651#endif 652 // Check if all new phi's inputs have specified alias index. 653 // Otherwise use old phi. 654 for (uint i = 1; i < phi->req(); i++) { 655 Node* in = result->in(i); 656 assert((phi->in(i) == NULL) == (in == NULL), "inputs must correspond."); 657 } 658 // we have finished processing a Phi, see if there are any more to do 659 finished = (phi_list.length() == 0 ); 660 if (!finished) { 661 phi = phi_list.pop(); 662 idx = cur_input.pop(); 663 PhiNode *prev_result = get_map_phi(phi->_idx); 664 prev_result->set_req(idx++, result); 665 result = prev_result; 666 } 667 } 668 return result; 669} 670 671 672// 673// The next methods are derived from methods in MemNode. 674// 675static Node *step_through_mergemem(MergeMemNode *mmem, int alias_idx, const TypeOopPtr *tinst) { 676 Node *mem = mmem; 677 // TypeInstPtr::NOTNULL+any is an OOP with unknown offset - generally 678 // means an array I have not precisely typed yet. Do not do any 679 // alias stuff with it any time soon. 680 if( tinst->base() != Type::AnyPtr && 681 !(tinst->klass()->is_java_lang_Object() && 682 tinst->offset() == Type::OffsetBot) ) { 683 mem = mmem->memory_at(alias_idx); 684 // Update input if it is progress over what we have now 685 } 686 return mem; 687} 688 689// 690// Search memory chain of "mem" to find a MemNode whose address 691// is the specified alias index. 692// 693Node* ConnectionGraph::find_inst_mem(Node *orig_mem, int alias_idx, GrowableArray<PhiNode *> &orig_phis, PhaseGVN *phase) { 694 if (orig_mem == NULL) 695 return orig_mem; 696 Compile* C = phase->C; 697 const TypeOopPtr *tinst = C->get_adr_type(alias_idx)->isa_oopptr(); 698 bool is_instance = (tinst != NULL) && tinst->is_known_instance(); 699 Node *start_mem = C->start()->proj_out(TypeFunc::Memory); 700 Node *prev = NULL; 701 Node *result = orig_mem; 702 while (prev != result) { 703 prev = result; 704 if (result == start_mem) 705 break; // hit one of our sentinals 706 if (result->is_Mem()) { 707 const Type *at = phase->type(result->in(MemNode::Address)); 708 if (at != Type::TOP) { 709 assert (at->isa_ptr() != NULL, "pointer type required."); 710 int idx = C->get_alias_index(at->is_ptr()); 711 if (idx == alias_idx) 712 break; 713 } 714 result = result->in(MemNode::Memory); 715 } 716 if (!is_instance) 717 continue; // don't search further for non-instance types 718 // skip over a call which does not affect this memory slice 719 if (result->is_Proj() && result->as_Proj()->_con == TypeFunc::Memory) { 720 Node *proj_in = result->in(0); 721 if (proj_in->is_Allocate() && proj_in->_idx == (uint)tinst->instance_id()) { 722 break; // hit one of our sentinals 723 } else if (proj_in->is_Call()) { 724 CallNode *call = proj_in->as_Call(); 725 if (!call->may_modify(tinst, phase)) { 726 result = call->in(TypeFunc::Memory); 727 } 728 } else if (proj_in->is_Initialize()) { 729 AllocateNode* alloc = proj_in->as_Initialize()->allocation(); 730 // Stop if this is the initialization for the object instance which 731 // which contains this memory slice, otherwise skip over it. 732 if (alloc == NULL || alloc->_idx != (uint)tinst->instance_id()) { 733 result = proj_in->in(TypeFunc::Memory); 734 } 735 } else if (proj_in->is_MemBar()) { 736 result = proj_in->in(TypeFunc::Memory); 737 } 738 } else if (result->is_MergeMem()) { 739 MergeMemNode *mmem = result->as_MergeMem(); 740 result = step_through_mergemem(mmem, alias_idx, tinst); 741 if (result == mmem->base_memory()) { 742 // Didn't find instance memory, search through general slice recursively. 743 result = mmem->memory_at(C->get_general_index(alias_idx)); 744 result = find_inst_mem(result, alias_idx, orig_phis, phase); 745 if (C->failing()) { 746 return NULL; 747 } 748 mmem->set_memory_at(alias_idx, result); 749 } 750 } else if (result->is_Phi() && 751 C->get_alias_index(result->as_Phi()->adr_type()) != alias_idx) { 752 Node *un = result->as_Phi()->unique_input(phase); 753 if (un != NULL) { 754 result = un; 755 } else { 756 break; 757 } 758 } 759 } 760 if (result->is_Phi()) { 761 PhiNode *mphi = result->as_Phi(); 762 assert(mphi->bottom_type() == Type::MEMORY, "memory phi required"); 763 const TypePtr *t = mphi->adr_type(); 764 if (C->get_alias_index(t) != alias_idx) { 765 // Create a new Phi with the specified alias index type. 766 result = split_memory_phi(mphi, alias_idx, orig_phis, phase); 767 } else if (!is_instance) { 768 // Push all non-instance Phis on the orig_phis worklist to update inputs 769 // during Phase 4 if needed. 770 orig_phis.append_if_missing(mphi); 771 } 772 } 773 // the result is either MemNode, PhiNode, InitializeNode. 774 return result; 775} 776 777 778// 779// Convert the types of unescaped object to instance types where possible, 780// propagate the new type information through the graph, and update memory 781// edges and MergeMem inputs to reflect the new type. 782// 783// We start with allocations (and calls which may be allocations) on alloc_worklist. 784// The processing is done in 4 phases: 785// 786// Phase 1: Process possible allocations from alloc_worklist. Create instance 787// types for the CheckCastPP for allocations where possible. 788// Propagate the the new types through users as follows: 789// casts and Phi: push users on alloc_worklist 790// AddP: cast Base and Address inputs to the instance type 791// push any AddP users on alloc_worklist and push any memnode 792// users onto memnode_worklist. 793// Phase 2: Process MemNode's from memnode_worklist. compute new address type and 794// search the Memory chain for a store with the appropriate type 795// address type. If a Phi is found, create a new version with 796// the approriate memory slices from each of the Phi inputs. 797// For stores, process the users as follows: 798// MemNode: push on memnode_worklist 799// MergeMem: push on mergemem_worklist 800// Phase 3: Process MergeMem nodes from mergemem_worklist. Walk each memory slice 801// moving the first node encountered of each instance type to the 802// the input corresponding to its alias index. 803// appropriate memory slice. 804// Phase 4: Update the inputs of non-instance memory Phis and the Memory input of memnodes. 805// 806// In the following example, the CheckCastPP nodes are the cast of allocation 807// results and the allocation of node 29 is unescaped and eligible to be an 808// instance type. 809// 810// We start with: 811// 812// 7 Parm #memory 813// 10 ConI "12" 814// 19 CheckCastPP "Foo" 815// 20 AddP _ 19 19 10 Foo+12 alias_index=4 816// 29 CheckCastPP "Foo" 817// 30 AddP _ 29 29 10 Foo+12 alias_index=4 818// 819// 40 StoreP 25 7 20 ... alias_index=4 820// 50 StoreP 35 40 30 ... alias_index=4 821// 60 StoreP 45 50 20 ... alias_index=4 822// 70 LoadP _ 60 30 ... alias_index=4 823// 80 Phi 75 50 60 Memory alias_index=4 824// 90 LoadP _ 80 30 ... alias_index=4 825// 100 LoadP _ 80 20 ... alias_index=4 826// 827// 828// Phase 1 creates an instance type for node 29 assigning it an instance id of 24 829// and creating a new alias index for node 30. This gives: 830// 831// 7 Parm #memory 832// 10 ConI "12" 833// 19 CheckCastPP "Foo" 834// 20 AddP _ 19 19 10 Foo+12 alias_index=4 835// 29 CheckCastPP "Foo" iid=24 836// 30 AddP _ 29 29 10 Foo+12 alias_index=6 iid=24 837// 838// 40 StoreP 25 7 20 ... alias_index=4 839// 50 StoreP 35 40 30 ... alias_index=6 840// 60 StoreP 45 50 20 ... alias_index=4 841// 70 LoadP _ 60 30 ... alias_index=6 842// 80 Phi 75 50 60 Memory alias_index=4 843// 90 LoadP _ 80 30 ... alias_index=6 844// 100 LoadP _ 80 20 ... alias_index=4 845// 846// In phase 2, new memory inputs are computed for the loads and stores, 847// And a new version of the phi is created. In phase 4, the inputs to 848// node 80 are updated and then the memory nodes are updated with the 849// values computed in phase 2. This results in: 850// 851// 7 Parm #memory 852// 10 ConI "12" 853// 19 CheckCastPP "Foo" 854// 20 AddP _ 19 19 10 Foo+12 alias_index=4 855// 29 CheckCastPP "Foo" iid=24 856// 30 AddP _ 29 29 10 Foo+12 alias_index=6 iid=24 857// 858// 40 StoreP 25 7 20 ... alias_index=4 859// 50 StoreP 35 7 30 ... alias_index=6 860// 60 StoreP 45 40 20 ... alias_index=4 861// 70 LoadP _ 50 30 ... alias_index=6 862// 80 Phi 75 40 60 Memory alias_index=4 863// 120 Phi 75 50 50 Memory alias_index=6 864// 90 LoadP _ 120 30 ... alias_index=6 865// 100 LoadP _ 80 20 ... alias_index=4 866// 867void ConnectionGraph::split_unique_types(GrowableArray<Node *> &alloc_worklist) { 868 GrowableArray<Node *> memnode_worklist; 869 GrowableArray<Node *> mergemem_worklist; 870 GrowableArray<PhiNode *> orig_phis; 871 PhaseGVN *igvn = _compile->initial_gvn(); 872 uint new_index_start = (uint) _compile->num_alias_types(); 873 VectorSet visited(Thread::current()->resource_area()); 874 VectorSet ptset(Thread::current()->resource_area()); 875 876 877 // Phase 1: Process possible allocations from alloc_worklist. 878 // Create instance types for the CheckCastPP for allocations where possible. 879 // 880 // (Note: don't forget to change the order of the second AddP node on 881 // the alloc_worklist if the order of the worklist processing is changed, 882 // see the comment in find_second_addp().) 883 // 884 while (alloc_worklist.length() != 0) { 885 Node *n = alloc_worklist.pop(); 886 uint ni = n->_idx; 887 const TypeOopPtr* tinst = NULL; 888 if (n->is_Call()) { 889 CallNode *alloc = n->as_Call(); 890 // copy escape information to call node 891 PointsToNode* ptn = ptnode_adr(alloc->_idx); 892 PointsToNode::EscapeState es = escape_state(alloc, igvn); 893 // We have an allocation or call which returns a Java object, 894 // see if it is unescaped. 895 if (es != PointsToNode::NoEscape || !ptn->_scalar_replaceable) 896 continue; 897 if (alloc->is_Allocate()) { 898 // Set the scalar_replaceable flag before the next check. 899 alloc->as_Allocate()->_is_scalar_replaceable = true; 900 } 901 // find CheckCastPP of call return value 902 n = alloc->result_cast(); 903 if (n == NULL || // No uses accept Initialize or 904 !n->is_CheckCastPP()) // not unique CheckCastPP. 905 continue; 906 // The inline code for Object.clone() casts the allocation result to 907 // java.lang.Object and then to the actual type of the allocated 908 // object. Detect this case and use the second cast. 909 // Also detect j.l.reflect.Array.newInstance(jobject, jint) case when 910 // the allocation result is cast to java.lang.Object and then 911 // to the actual Array type. 912 if (alloc->is_Allocate() && n->as_Type()->type() == TypeInstPtr::NOTNULL 913 && (alloc->is_AllocateArray() || 914 igvn->type(alloc->in(AllocateNode::KlassNode)) != TypeKlassPtr::OBJECT)) { 915 Node *cast2 = NULL; 916 for (DUIterator_Fast imax, i = n->fast_outs(imax); i < imax; i++) { 917 Node *use = n->fast_out(i); 918 if (use->is_CheckCastPP()) { 919 cast2 = use; 920 break; 921 } 922 } 923 if (cast2 != NULL) { 924 n = cast2; 925 } else { 926 continue; 927 } 928 } 929 set_escape_state(n->_idx, es); 930 // in order for an object to be scalar-replaceable, it must be: 931 // - a direct allocation (not a call returning an object) 932 // - non-escaping 933 // - eligible to be a unique type 934 // - not determined to be ineligible by escape analysis 935 set_map(alloc->_idx, n); 936 set_map(n->_idx, alloc); 937 const TypeOopPtr *t = igvn->type(n)->isa_oopptr(); 938 if (t == NULL) 939 continue; // not a TypeInstPtr 940 tinst = t->cast_to_exactness(true)->is_oopptr()->cast_to_instance_id(ni); 941 igvn->hash_delete(n); 942 igvn->set_type(n, tinst); 943 n->raise_bottom_type(tinst); 944 igvn->hash_insert(n); 945 record_for_optimizer(n); 946 if (alloc->is_Allocate() && ptn->_scalar_replaceable && 947 (t->isa_instptr() || t->isa_aryptr())) { 948 949 // First, put on the worklist all Field edges from Connection Graph 950 // which is more accurate then putting immediate users from Ideal Graph. 951 for (uint e = 0; e < ptn->edge_count(); e++) { 952 Node *use = ptnode_adr(ptn->edge_target(e))->_node; 953 assert(ptn->edge_type(e) == PointsToNode::FieldEdge && use->is_AddP(), 954 "only AddP nodes are Field edges in CG"); 955 if (use->outcnt() > 0) { // Don't process dead nodes 956 Node* addp2 = find_second_addp(use, use->in(AddPNode::Base)); 957 if (addp2 != NULL) { 958 assert(alloc->is_AllocateArray(),"array allocation was expected"); 959 alloc_worklist.append_if_missing(addp2); 960 } 961 alloc_worklist.append_if_missing(use); 962 } 963 } 964 965 // An allocation may have an Initialize which has raw stores. Scan 966 // the users of the raw allocation result and push AddP users 967 // on alloc_worklist. 968 Node *raw_result = alloc->proj_out(TypeFunc::Parms); 969 assert (raw_result != NULL, "must have an allocation result"); 970 for (DUIterator_Fast imax, i = raw_result->fast_outs(imax); i < imax; i++) { 971 Node *use = raw_result->fast_out(i); 972 if (use->is_AddP() && use->outcnt() > 0) { // Don't process dead nodes 973 Node* addp2 = find_second_addp(use, raw_result); 974 if (addp2 != NULL) { 975 assert(alloc->is_AllocateArray(),"array allocation was expected"); 976 alloc_worklist.append_if_missing(addp2); 977 } 978 alloc_worklist.append_if_missing(use); 979 } else if (use->is_Initialize()) { 980 memnode_worklist.append_if_missing(use); 981 } 982 } 983 } 984 } else if (n->is_AddP()) { 985 ptset.Clear(); 986 PointsTo(ptset, get_addp_base(n), igvn); 987 assert(ptset.Size() == 1, "AddP address is unique"); 988 uint elem = ptset.getelem(); // Allocation node's index 989 if (elem == _phantom_object) 990 continue; // Assume the value was set outside this method. 991 Node *base = get_map(elem); // CheckCastPP node 992 if (!split_AddP(n, base, igvn)) continue; // wrong type 993 tinst = igvn->type(base)->isa_oopptr(); 994 } else if (n->is_Phi() || 995 n->is_CheckCastPP() || 996 n->is_EncodeP() || 997 n->is_DecodeN() || 998 (n->is_ConstraintCast() && n->Opcode() == Op_CastPP)) { 999 if (visited.test_set(n->_idx)) { 1000 assert(n->is_Phi(), "loops only through Phi's"); 1001 continue; // already processed 1002 } 1003 ptset.Clear(); 1004 PointsTo(ptset, n, igvn); 1005 if (ptset.Size() == 1) { 1006 uint elem = ptset.getelem(); // Allocation node's index 1007 if (elem == _phantom_object) 1008 continue; // Assume the value was set outside this method. 1009 Node *val = get_map(elem); // CheckCastPP node 1010 TypeNode *tn = n->as_Type(); 1011 tinst = igvn->type(val)->isa_oopptr(); 1012 assert(tinst != NULL && tinst->is_known_instance() && 1013 (uint)tinst->instance_id() == elem , "instance type expected."); 1014 1015 const Type *tn_type = igvn->type(tn); 1016 const TypeOopPtr *tn_t; 1017 if (tn_type->isa_narrowoop()) { 1018 tn_t = tn_type->make_ptr()->isa_oopptr(); 1019 } else { 1020 tn_t = tn_type->isa_oopptr(); 1021 } 1022 1023 if (tn_t != NULL && 1024 tinst->cast_to_instance_id(TypeOopPtr::InstanceBot)->higher_equal(tn_t)) { 1025 if (tn_type->isa_narrowoop()) { 1026 tn_type = tinst->make_narrowoop(); 1027 } else { 1028 tn_type = tinst; 1029 } 1030 igvn->hash_delete(tn); 1031 igvn->set_type(tn, tn_type); 1032 tn->set_type(tn_type); 1033 igvn->hash_insert(tn); 1034 record_for_optimizer(n); 1035 } else { 1036 continue; // wrong type 1037 } 1038 } 1039 } else { 1040 continue; 1041 } 1042 // push users on appropriate worklist 1043 for (DUIterator_Fast imax, i = n->fast_outs(imax); i < imax; i++) { 1044 Node *use = n->fast_out(i); 1045 if(use->is_Mem() && use->in(MemNode::Address) == n) { 1046 memnode_worklist.append_if_missing(use); 1047 } else if (use->is_Initialize()) { 1048 memnode_worklist.append_if_missing(use); 1049 } else if (use->is_MergeMem()) { 1050 mergemem_worklist.append_if_missing(use); 1051 } else if (use->is_SafePoint() && tinst != NULL) { 1052 // Look for MergeMem nodes for calls which reference unique allocation 1053 // (through CheckCastPP nodes) even for debug info. 1054 Node* m = use->in(TypeFunc::Memory); 1055 uint iid = tinst->instance_id(); 1056 while (m->is_Proj() && m->in(0)->is_SafePoint() && 1057 m->in(0) != use && !m->in(0)->_idx != iid) { 1058 m = m->in(0)->in(TypeFunc::Memory); 1059 } 1060 if (m->is_MergeMem()) { 1061 mergemem_worklist.append_if_missing(m); 1062 } 1063 } else if (use->is_AddP() && use->outcnt() > 0) { // No dead nodes 1064 Node* addp2 = find_second_addp(use, n); 1065 if (addp2 != NULL) { 1066 alloc_worklist.append_if_missing(addp2); 1067 } 1068 alloc_worklist.append_if_missing(use); 1069 } else if (use->is_Phi() || 1070 use->is_CheckCastPP() || 1071 use->is_EncodeP() || 1072 use->is_DecodeN() || 1073 (use->is_ConstraintCast() && use->Opcode() == Op_CastPP)) { 1074 alloc_worklist.append_if_missing(use); 1075 } 1076 } 1077 1078 } 1079 // New alias types were created in split_AddP(). 1080 uint new_index_end = (uint) _compile->num_alias_types(); 1081 1082 // Phase 2: Process MemNode's from memnode_worklist. compute new address type and 1083 // compute new values for Memory inputs (the Memory inputs are not 1084 // actually updated until phase 4.) 1085 if (memnode_worklist.length() == 0) 1086 return; // nothing to do 1087 1088 while (memnode_worklist.length() != 0) { 1089 Node *n = memnode_worklist.pop(); 1090 if (visited.test_set(n->_idx)) 1091 continue; 1092 if (n->is_Phi()) { 1093 assert(n->as_Phi()->adr_type() != TypePtr::BOTTOM, "narrow memory slice required"); 1094 // we don't need to do anything, but the users must be pushed if we haven't processed 1095 // this Phi before 1096 } else if (n->is_Initialize()) { 1097 // we don't need to do anything, but the users of the memory projection must be pushed 1098 n = n->as_Initialize()->proj_out(TypeFunc::Memory); 1099 if (n == NULL) 1100 continue; 1101 } else { 1102 assert(n->is_Mem(), "memory node required."); 1103 Node *addr = n->in(MemNode::Address); 1104 assert(addr->is_AddP(), "AddP required"); 1105 const Type *addr_t = igvn->type(addr); 1106 if (addr_t == Type::TOP) 1107 continue; 1108 assert (addr_t->isa_ptr() != NULL, "pointer type required."); 1109 int alias_idx = _compile->get_alias_index(addr_t->is_ptr()); 1110 assert ((uint)alias_idx < new_index_end, "wrong alias index"); 1111 Node *mem = find_inst_mem(n->in(MemNode::Memory), alias_idx, orig_phis, igvn); 1112 if (_compile->failing()) { 1113 return; 1114 } 1115 if (mem != n->in(MemNode::Memory)) { 1116 set_map(n->_idx, mem); 1117 ptnode_adr(n->_idx)->_node = n; 1118 } 1119 if (n->is_Load()) { 1120 continue; // don't push users 1121 } else if (n->is_LoadStore()) { 1122 // get the memory projection 1123 for (DUIterator_Fast imax, i = n->fast_outs(imax); i < imax; i++) { 1124 Node *use = n->fast_out(i); 1125 if (use->Opcode() == Op_SCMemProj) { 1126 n = use; 1127 break; 1128 } 1129 } 1130 assert(n->Opcode() == Op_SCMemProj, "memory projection required"); 1131 } 1132 } 1133 // push user on appropriate worklist 1134 for (DUIterator_Fast imax, i = n->fast_outs(imax); i < imax; i++) { 1135 Node *use = n->fast_out(i); 1136 if (use->is_Phi()) { 1137 memnode_worklist.append_if_missing(use); 1138 } else if(use->is_Mem() && use->in(MemNode::Memory) == n) { 1139 memnode_worklist.append_if_missing(use); 1140 } else if (use->is_Initialize()) { 1141 memnode_worklist.append_if_missing(use); 1142 } else if (use->is_MergeMem()) { 1143 mergemem_worklist.append_if_missing(use); 1144 } 1145 } 1146 } 1147 1148 // Phase 3: Process MergeMem nodes from mergemem_worklist. 1149 // Walk each memory moving the first node encountered of each 1150 // instance type to the the input corresponding to its alias index. 1151 while (mergemem_worklist.length() != 0) { 1152 Node *n = mergemem_worklist.pop(); 1153 assert(n->is_MergeMem(), "MergeMem node required."); 1154 if (visited.test_set(n->_idx)) 1155 continue; 1156 MergeMemNode *nmm = n->as_MergeMem(); 1157 // Note: we don't want to use MergeMemStream here because we only want to 1158 // scan inputs which exist at the start, not ones we add during processing. 1159 uint nslices = nmm->req(); 1160 igvn->hash_delete(nmm); 1161 for (uint i = Compile::AliasIdxRaw+1; i < nslices; i++) { 1162 Node* mem = nmm->in(i); 1163 Node* cur = NULL; 1164 if (mem == NULL || mem->is_top()) 1165 continue; 1166 while (mem->is_Mem()) { 1167 const Type *at = igvn->type(mem->in(MemNode::Address)); 1168 if (at != Type::TOP) { 1169 assert (at->isa_ptr() != NULL, "pointer type required."); 1170 uint idx = (uint)_compile->get_alias_index(at->is_ptr()); 1171 if (idx == i) { 1172 if (cur == NULL) 1173 cur = mem; 1174 } else { 1175 if (idx >= nmm->req() || nmm->is_empty_memory(nmm->in(idx))) { 1176 nmm->set_memory_at(idx, mem); 1177 } 1178 } 1179 } 1180 mem = mem->in(MemNode::Memory); 1181 } 1182 nmm->set_memory_at(i, (cur != NULL) ? cur : mem); 1183 // Find any instance of the current type if we haven't encountered 1184 // a value of the instance along the chain. 1185 for (uint ni = new_index_start; ni < new_index_end; ni++) { 1186 if((uint)_compile->get_general_index(ni) == i) { 1187 Node *m = (ni >= nmm->req()) ? nmm->empty_memory() : nmm->in(ni); 1188 if (nmm->is_empty_memory(m)) { 1189 Node* result = find_inst_mem(mem, ni, orig_phis, igvn); 1190 if (_compile->failing()) { 1191 return; 1192 } 1193 nmm->set_memory_at(ni, result); 1194 } 1195 } 1196 } 1197 } 1198 // Find the rest of instances values 1199 for (uint ni = new_index_start; ni < new_index_end; ni++) { 1200 const TypeOopPtr *tinst = igvn->C->get_adr_type(ni)->isa_oopptr(); 1201 Node* result = step_through_mergemem(nmm, ni, tinst); 1202 if (result == nmm->base_memory()) { 1203 // Didn't find instance memory, search through general slice recursively. 1204 result = nmm->memory_at(igvn->C->get_general_index(ni)); 1205 result = find_inst_mem(result, ni, orig_phis, igvn); 1206 if (_compile->failing()) { 1207 return; 1208 } 1209 nmm->set_memory_at(ni, result); 1210 } 1211 } 1212 igvn->hash_insert(nmm); 1213 record_for_optimizer(nmm); 1214 1215 // Propagate new memory slices to following MergeMem nodes. 1216 for (DUIterator_Fast imax, i = n->fast_outs(imax); i < imax; i++) { 1217 Node *use = n->fast_out(i); 1218 if (use->is_Call()) { 1219 CallNode* in = use->as_Call(); 1220 if (in->proj_out(TypeFunc::Memory) != NULL) { 1221 Node* m = in->proj_out(TypeFunc::Memory); 1222 for (DUIterator_Fast jmax, j = m->fast_outs(jmax); j < jmax; j++) { 1223 Node* mm = m->fast_out(j); 1224 if (mm->is_MergeMem()) { 1225 mergemem_worklist.append_if_missing(mm); 1226 } 1227 } 1228 } 1229 if (use->is_Allocate()) { 1230 use = use->as_Allocate()->initialization(); 1231 if (use == NULL) { 1232 continue; 1233 } 1234 } 1235 } 1236 if (use->is_Initialize()) { 1237 InitializeNode* in = use->as_Initialize(); 1238 if (in->proj_out(TypeFunc::Memory) != NULL) { 1239 Node* m = in->proj_out(TypeFunc::Memory); 1240 for (DUIterator_Fast jmax, j = m->fast_outs(jmax); j < jmax; j++) { 1241 Node* mm = m->fast_out(j); 1242 if (mm->is_MergeMem()) { 1243 mergemem_worklist.append_if_missing(mm); 1244 } 1245 } 1246 } 1247 } 1248 } 1249 } 1250 1251 // Phase 4: Update the inputs of non-instance memory Phis and 1252 // the Memory input of memnodes 1253 // First update the inputs of any non-instance Phi's from 1254 // which we split out an instance Phi. Note we don't have 1255 // to recursively process Phi's encounted on the input memory 1256 // chains as is done in split_memory_phi() since they will 1257 // also be processed here. 1258 for (int j = 0; j < orig_phis.length(); j++) { 1259 PhiNode *phi = orig_phis.at(j); 1260 int alias_idx = _compile->get_alias_index(phi->adr_type()); 1261 igvn->hash_delete(phi); 1262 for (uint i = 1; i < phi->req(); i++) { 1263 Node *mem = phi->in(i); 1264 Node *new_mem = find_inst_mem(mem, alias_idx, orig_phis, igvn); 1265 if (_compile->failing()) { 1266 return; 1267 } 1268 if (mem != new_mem) { 1269 phi->set_req(i, new_mem); 1270 } 1271 } 1272 igvn->hash_insert(phi); 1273 record_for_optimizer(phi); 1274 } 1275 1276 // Update the memory inputs of MemNodes with the value we computed 1277 // in Phase 2. 1278 for (uint i = 0; i < nodes_size(); i++) { 1279 Node *nmem = get_map(i); 1280 if (nmem != NULL) { 1281 Node *n = ptnode_adr(i)->_node; 1282 if (n != NULL && n->is_Mem()) { 1283 igvn->hash_delete(n); 1284 n->set_req(MemNode::Memory, nmem); 1285 igvn->hash_insert(n); 1286 record_for_optimizer(n); 1287 } 1288 } 1289 } 1290} 1291 1292bool ConnectionGraph::has_candidates(Compile *C) { 1293 // EA brings benefits only when the code has allocations and/or locks which 1294 // are represented by ideal Macro nodes. 1295 int cnt = C->macro_count(); 1296 for( int i=0; i < cnt; i++ ) { 1297 Node *n = C->macro_node(i); 1298 if ( n->is_Allocate() ) 1299 return true; 1300 if( n->is_Lock() ) { 1301 Node* obj = n->as_Lock()->obj_node()->uncast(); 1302 if( !(obj->is_Parm() || obj->is_Con()) ) 1303 return true; 1304 } 1305 } 1306 return false; 1307} 1308 1309bool ConnectionGraph::compute_escape() { 1310 Compile* C = _compile; 1311 1312 // 1. Populate Connection Graph (CG) with Ideal nodes. 1313 1314 Unique_Node_List worklist_init; 1315 worklist_init.map(C->unique(), NULL); // preallocate space 1316 1317 // Initialize worklist 1318 if (C->root() != NULL) { 1319 worklist_init.push(C->root()); 1320 } 1321 1322 GrowableArray<int> cg_worklist; 1323 PhaseGVN* igvn = C->initial_gvn(); 1324 bool has_allocations = false; 1325 1326 // Push all useful nodes onto CG list and set their type. 1327 for( uint next = 0; next < worklist_init.size(); ++next ) { 1328 Node* n = worklist_init.at(next); 1329 record_for_escape_analysis(n, igvn); 1330 // Only allocations and java static calls results are checked 1331 // for an escape status. See process_call_result() below. 1332 if (n->is_Allocate() || n->is_CallStaticJava() && 1333 ptnode_adr(n->_idx)->node_type() == PointsToNode::JavaObject) { 1334 has_allocations = true; 1335 } 1336 if(n->is_AddP()) 1337 cg_worklist.append(n->_idx); 1338 for (DUIterator_Fast imax, i = n->fast_outs(imax); i < imax; i++) { 1339 Node* m = n->fast_out(i); // Get user 1340 worklist_init.push(m); 1341 } 1342 } 1343 1344 if (!has_allocations) { 1345 _collecting = false; 1346 return false; // Nothing to do. 1347 } 1348 1349 // 2. First pass to create simple CG edges (doesn't require to walk CG). 1350 uint delayed_size = _delayed_worklist.size(); 1351 for( uint next = 0; next < delayed_size; ++next ) { 1352 Node* n = _delayed_worklist.at(next); 1353 build_connection_graph(n, igvn); 1354 } 1355 1356 // 3. Pass to create fields edges (Allocate -F-> AddP). 1357 uint cg_length = cg_worklist.length(); 1358 for( uint next = 0; next < cg_length; ++next ) { 1359 int ni = cg_worklist.at(next); 1360 build_connection_graph(ptnode_adr(ni)->_node, igvn); 1361 } 1362 1363 cg_worklist.clear(); 1364 cg_worklist.append(_phantom_object); 1365 1366 // 4. Build Connection Graph which need 1367 // to walk the connection graph. 1368 for (uint ni = 0; ni < nodes_size(); ni++) { 1369 PointsToNode* ptn = ptnode_adr(ni); 1370 Node *n = ptn->_node; 1371 if (n != NULL) { // Call, AddP, LoadP, StoreP 1372 build_connection_graph(n, igvn); 1373 if (ptn->node_type() != PointsToNode::UnknownType) 1374 cg_worklist.append(n->_idx); // Collect CG nodes 1375 } 1376 } 1377 1378 VectorSet ptset(Thread::current()->resource_area()); 1379 GrowableArray<uint> deferred_edges; 1380 VectorSet visited(Thread::current()->resource_area()); 1381 1382 // 5. Remove deferred edges from the graph and collect 1383 // information needed for type splitting. 1384 cg_length = cg_worklist.length(); 1385 for( uint next = 0; next < cg_length; ++next ) { 1386 int ni = cg_worklist.at(next); 1387 PointsToNode* ptn = ptnode_adr(ni); 1388 PointsToNode::NodeType nt = ptn->node_type(); 1389 if (nt == PointsToNode::LocalVar || nt == PointsToNode::Field) { 1390 remove_deferred(ni, &deferred_edges, &visited); 1391 Node *n = ptn->_node; 1392 if (n->is_AddP()) { 1393 // Search for objects which are not scalar replaceable. 1394 // Mark their escape state as ArgEscape to propagate the state 1395 // to referenced objects. 1396 // Note: currently there are no difference in compiler optimizations 1397 // for ArgEscape objects and NoEscape objects which are not 1398 // scalar replaceable. 1399 1400 int offset = ptn->offset(); 1401 Node *base = get_addp_base(n); 1402 ptset.Clear(); 1403 PointsTo(ptset, base, igvn); 1404 int ptset_size = ptset.Size(); 1405 1406 // Check if a field's initializing value is recorded and add 1407 // a corresponding NULL field's value if it is not recorded. 1408 // Connection Graph does not record a default initialization by NULL 1409 // captured by Initialize node. 1410 // 1411 // Note: it will disable scalar replacement in some cases: 1412 // 1413 // Point p[] = new Point[1]; 1414 // p[0] = new Point(); // Will be not scalar replaced 1415 // 1416 // but it will save us from incorrect optimizations in next cases: 1417 // 1418 // Point p[] = new Point[1]; 1419 // if ( x ) p[0] = new Point(); // Will be not scalar replaced 1420 // 1421 // Without a control flow analysis we can't distinguish above cases. 1422 // 1423 if (offset != Type::OffsetBot && ptset_size == 1) { 1424 uint elem = ptset.getelem(); // Allocation node's index 1425 // It does not matter if it is not Allocation node since 1426 // only non-escaping allocations are scalar replaced. 1427 if (ptnode_adr(elem)->_node->is_Allocate() && 1428 ptnode_adr(elem)->escape_state() == PointsToNode::NoEscape) { 1429 AllocateNode* alloc = ptnode_adr(elem)->_node->as_Allocate(); 1430 InitializeNode* ini = alloc->initialization(); 1431 Node* value = NULL; 1432 if (ini != NULL) { 1433 BasicType ft = UseCompressedOops ? T_NARROWOOP : T_OBJECT; 1434 Node* store = ini->find_captured_store(offset, type2aelembytes(ft), igvn); 1435 if (store != NULL && store->is_Store()) 1436 value = store->in(MemNode::ValueIn); 1437 } 1438 if (value == NULL || value != ptnode_adr(value->_idx)->_node) { 1439 // A field's initializing value was not recorded. Add NULL. 1440 uint null_idx = UseCompressedOops ? _noop_null : _oop_null; 1441 add_pointsto_edge(ni, null_idx); 1442 } 1443 } 1444 } 1445 1446 // An object is not scalar replaceable if the field which may point 1447 // to it has unknown offset (unknown element of an array of objects). 1448 // 1449 if (offset == Type::OffsetBot) { 1450 uint e_cnt = ptn->edge_count(); 1451 for (uint ei = 0; ei < e_cnt; ei++) { 1452 uint npi = ptn->edge_target(ei); 1453 set_escape_state(npi, PointsToNode::ArgEscape); 1454 ptnode_adr(npi)->_scalar_replaceable = false; 1455 } 1456 } 1457 1458 // Currently an object is not scalar replaceable if a LoadStore node 1459 // access its field since the field value is unknown after it. 1460 // 1461 bool has_LoadStore = false; 1462 for (DUIterator_Fast imax, i = n->fast_outs(imax); i < imax; i++) { 1463 Node *use = n->fast_out(i); 1464 if (use->is_LoadStore()) { 1465 has_LoadStore = true; 1466 break; 1467 } 1468 } 1469 // An object is not scalar replaceable if the address points 1470 // to unknown field (unknown element for arrays, offset is OffsetBot). 1471 // 1472 // Or the address may point to more then one object. This may produce 1473 // the false positive result (set scalar_replaceable to false) 1474 // since the flow-insensitive escape analysis can't separate 1475 // the case when stores overwrite the field's value from the case 1476 // when stores happened on different control branches. 1477 // 1478 if (ptset_size > 1 || ptset_size != 0 && 1479 (has_LoadStore || offset == Type::OffsetBot)) { 1480 for( VectorSetI j(&ptset); j.test(); ++j ) { 1481 set_escape_state(j.elem, PointsToNode::ArgEscape); 1482 ptnode_adr(j.elem)->_scalar_replaceable = false; 1483 } 1484 } 1485 } 1486 } 1487 } 1488 1489 // 6. Propagate escape states. 1490 GrowableArray<int> worklist; 1491 bool has_non_escaping_obj = false; 1492 1493 // push all GlobalEscape nodes on the worklist 1494 for( uint next = 0; next < cg_length; ++next ) { 1495 int nk = cg_worklist.at(next); 1496 if (ptnode_adr(nk)->escape_state() == PointsToNode::GlobalEscape) 1497 worklist.push(nk); 1498 } 1499 // mark all nodes reachable from GlobalEscape nodes 1500 while(worklist.length() > 0) { 1501 PointsToNode* ptn = ptnode_adr(worklist.pop()); 1502 uint e_cnt = ptn->edge_count(); 1503 for (uint ei = 0; ei < e_cnt; ei++) { 1504 uint npi = ptn->edge_target(ei); 1505 PointsToNode *np = ptnode_adr(npi); 1506 if (np->escape_state() < PointsToNode::GlobalEscape) { 1507 np->set_escape_state(PointsToNode::GlobalEscape); 1508 worklist.push(npi); 1509 } 1510 } 1511 } 1512 1513 // push all ArgEscape nodes on the worklist 1514 for( uint next = 0; next < cg_length; ++next ) { 1515 int nk = cg_worklist.at(next); 1516 if (ptnode_adr(nk)->escape_state() == PointsToNode::ArgEscape) 1517 worklist.push(nk); 1518 } 1519 // mark all nodes reachable from ArgEscape nodes 1520 while(worklist.length() > 0) { 1521 PointsToNode* ptn = ptnode_adr(worklist.pop()); 1522 if (ptn->node_type() == PointsToNode::JavaObject) 1523 has_non_escaping_obj = true; // Non GlobalEscape 1524 uint e_cnt = ptn->edge_count(); 1525 for (uint ei = 0; ei < e_cnt; ei++) { 1526 uint npi = ptn->edge_target(ei); 1527 PointsToNode *np = ptnode_adr(npi); 1528 if (np->escape_state() < PointsToNode::ArgEscape) { 1529 np->set_escape_state(PointsToNode::ArgEscape); 1530 worklist.push(npi); 1531 } 1532 } 1533 } 1534 1535 GrowableArray<Node*> alloc_worklist; 1536 1537 // push all NoEscape nodes on the worklist 1538 for( uint next = 0; next < cg_length; ++next ) { 1539 int nk = cg_worklist.at(next); 1540 if (ptnode_adr(nk)->escape_state() == PointsToNode::NoEscape) 1541 worklist.push(nk); 1542 } 1543 // mark all nodes reachable from NoEscape nodes 1544 while(worklist.length() > 0) { 1545 PointsToNode* ptn = ptnode_adr(worklist.pop()); 1546 if (ptn->node_type() == PointsToNode::JavaObject) 1547 has_non_escaping_obj = true; // Non GlobalEscape 1548 Node* n = ptn->_node; 1549 if (n->is_Allocate() && ptn->_scalar_replaceable ) { 1550 // Push scalar replaceable alocations on alloc_worklist 1551 // for processing in split_unique_types(). 1552 alloc_worklist.append(n); 1553 } 1554 uint e_cnt = ptn->edge_count(); 1555 for (uint ei = 0; ei < e_cnt; ei++) { 1556 uint npi = ptn->edge_target(ei); 1557 PointsToNode *np = ptnode_adr(npi); 1558 if (np->escape_state() < PointsToNode::NoEscape) { 1559 np->set_escape_state(PointsToNode::NoEscape); 1560 worklist.push(npi); 1561 } 1562 } 1563 } 1564 1565 _collecting = false; 1566 assert(C->unique() == nodes_size(), "there should be no new ideal nodes during ConnectionGraph build"); 1567 1568 bool has_scalar_replaceable_candidates = alloc_worklist.length() > 0; 1569 if ( has_scalar_replaceable_candidates && 1570 C->AliasLevel() >= 3 && EliminateAllocations ) { 1571 1572 // Now use the escape information to create unique types for 1573 // scalar replaceable objects. 1574 split_unique_types(alloc_worklist); 1575 1576 if (C->failing()) return false; 1577 1578 // Clean up after split unique types. 1579 ResourceMark rm; 1580 PhaseRemoveUseless pru(C->initial_gvn(), C->for_igvn()); 1581 1582 C->print_method("After Escape Analysis", 2); 1583 1584#ifdef ASSERT 1585 } else if (Verbose && (PrintEscapeAnalysis || PrintEliminateAllocations)) { 1586 tty->print("=== No allocations eliminated for "); 1587 C->method()->print_short_name(); 1588 if(!EliminateAllocations) { 1589 tty->print(" since EliminateAllocations is off ==="); 1590 } else if(!has_scalar_replaceable_candidates) { 1591 tty->print(" since there are no scalar replaceable candidates ==="); 1592 } else if(C->AliasLevel() < 3) { 1593 tty->print(" since AliasLevel < 3 ==="); 1594 } 1595 tty->cr(); 1596#endif 1597 } 1598 return has_non_escaping_obj; 1599} 1600 1601void ConnectionGraph::process_call_arguments(CallNode *call, PhaseTransform *phase) { 1602 1603 switch (call->Opcode()) { 1604#ifdef ASSERT 1605 case Op_Allocate: 1606 case Op_AllocateArray: 1607 case Op_Lock: 1608 case Op_Unlock: 1609 assert(false, "should be done already"); 1610 break; 1611#endif 1612 case Op_CallLeafNoFP: 1613 { 1614 // Stub calls, objects do not escape but they are not scale replaceable. 1615 // Adjust escape state for outgoing arguments. 1616 const TypeTuple * d = call->tf()->domain(); 1617 VectorSet ptset(Thread::current()->resource_area()); 1618 for (uint i = TypeFunc::Parms; i < d->cnt(); i++) { 1619 const Type* at = d->field_at(i); 1620 Node *arg = call->in(i)->uncast(); 1621 const Type *aat = phase->type(arg); 1622 if (!arg->is_top() && at->isa_ptr() && aat->isa_ptr()) { 1623 assert(aat == Type::TOP || aat == TypePtr::NULL_PTR || 1624 aat->isa_ptr() != NULL, "expecting an Ptr"); 1625 set_escape_state(arg->_idx, PointsToNode::ArgEscape); 1626 if (arg->is_AddP()) { 1627 // 1628 // The inline_native_clone() case when the arraycopy stub is called 1629 // after the allocation before Initialize and CheckCastPP nodes. 1630 // 1631 // Set AddP's base (Allocate) as not scalar replaceable since 1632 // pointer to the base (with offset) is passed as argument. 1633 // 1634 arg = get_addp_base(arg); 1635 } 1636 ptset.Clear(); 1637 PointsTo(ptset, arg, phase); 1638 for( VectorSetI j(&ptset); j.test(); ++j ) { 1639 uint pt = j.elem; 1640 set_escape_state(pt, PointsToNode::ArgEscape); 1641 } 1642 } 1643 } 1644 break; 1645 } 1646 1647 case Op_CallStaticJava: 1648 // For a static call, we know exactly what method is being called. 1649 // Use bytecode estimator to record the call's escape affects 1650 { 1651 ciMethod *meth = call->as_CallJava()->method(); 1652 BCEscapeAnalyzer *call_analyzer = (meth !=NULL) ? meth->get_bcea() : NULL; 1653 // fall-through if not a Java method or no analyzer information 1654 if (call_analyzer != NULL) { 1655 const TypeTuple * d = call->tf()->domain(); 1656 VectorSet ptset(Thread::current()->resource_area()); 1657 bool copy_dependencies = false; 1658 for (uint i = TypeFunc::Parms; i < d->cnt(); i++) { 1659 const Type* at = d->field_at(i); 1660 int k = i - TypeFunc::Parms; 1661 1662 if (at->isa_oopptr() != NULL) { 1663 Node *arg = call->in(i)->uncast(); 1664 1665 bool global_escapes = false; 1666 bool fields_escapes = false; 1667 if (!call_analyzer->is_arg_stack(k)) { 1668 // The argument global escapes, mark everything it could point to 1669 set_escape_state(arg->_idx, PointsToNode::GlobalEscape); 1670 global_escapes = true; 1671 } else { 1672 if (!call_analyzer->is_arg_local(k)) { 1673 // The argument itself doesn't escape, but any fields might 1674 fields_escapes = true; 1675 } 1676 set_escape_state(arg->_idx, PointsToNode::ArgEscape); 1677 copy_dependencies = true; 1678 } 1679 1680 ptset.Clear(); 1681 PointsTo(ptset, arg, phase); 1682 for( VectorSetI j(&ptset); j.test(); ++j ) { 1683 uint pt = j.elem; 1684 if (global_escapes) { 1685 //The argument global escapes, mark everything it could point to 1686 set_escape_state(pt, PointsToNode::GlobalEscape); 1687 } else { 1688 if (fields_escapes) { 1689 // The argument itself doesn't escape, but any fields might 1690 add_edge_from_fields(pt, _phantom_object, Type::OffsetBot); 1691 } 1692 set_escape_state(pt, PointsToNode::ArgEscape); 1693 } 1694 } 1695 } 1696 } 1697 if (copy_dependencies) 1698 call_analyzer->copy_dependencies(_compile->dependencies()); 1699 break; 1700 } 1701 } 1702 1703 default: 1704 // Fall-through here if not a Java method or no analyzer information 1705 // or some other type of call, assume the worst case: all arguments 1706 // globally escape. 1707 { 1708 // adjust escape state for outgoing arguments 1709 const TypeTuple * d = call->tf()->domain(); 1710 VectorSet ptset(Thread::current()->resource_area()); 1711 for (uint i = TypeFunc::Parms; i < d->cnt(); i++) { 1712 const Type* at = d->field_at(i); 1713 if (at->isa_oopptr() != NULL) { 1714 Node *arg = call->in(i)->uncast(); 1715 set_escape_state(arg->_idx, PointsToNode::GlobalEscape); 1716 ptset.Clear(); 1717 PointsTo(ptset, arg, phase); 1718 for( VectorSetI j(&ptset); j.test(); ++j ) { 1719 uint pt = j.elem; 1720 set_escape_state(pt, PointsToNode::GlobalEscape); 1721 } 1722 } 1723 } 1724 } 1725 } 1726} 1727void ConnectionGraph::process_call_result(ProjNode *resproj, PhaseTransform *phase) { 1728 CallNode *call = resproj->in(0)->as_Call(); 1729 uint call_idx = call->_idx; 1730 uint resproj_idx = resproj->_idx; 1731 1732 switch (call->Opcode()) { 1733 case Op_Allocate: 1734 { 1735 Node *k = call->in(AllocateNode::KlassNode); 1736 const TypeKlassPtr *kt; 1737 if (k->Opcode() == Op_LoadKlass) { 1738 kt = k->as_Load()->type()->isa_klassptr(); 1739 } else { 1740 // Also works for DecodeN(LoadNKlass). 1741 kt = k->as_Type()->type()->isa_klassptr(); 1742 } 1743 assert(kt != NULL, "TypeKlassPtr required."); 1744 ciKlass* cik = kt->klass(); 1745 ciInstanceKlass* ciik = cik->as_instance_klass(); 1746 1747 PointsToNode::EscapeState es; 1748 uint edge_to; 1749 if (cik->is_subclass_of(_compile->env()->Thread_klass()) || ciik->has_finalizer()) { 1750 es = PointsToNode::GlobalEscape; 1751 edge_to = _phantom_object; // Could not be worse 1752 } else { 1753 es = PointsToNode::NoEscape; 1754 edge_to = call_idx; 1755 } 1756 set_escape_state(call_idx, es); 1757 add_pointsto_edge(resproj_idx, edge_to); 1758 _processed.set(resproj_idx); 1759 break; 1760 } 1761 1762 case Op_AllocateArray: 1763 { 1764 int length = call->in(AllocateNode::ALength)->find_int_con(-1); 1765 if (length < 0 || length > EliminateAllocationArraySizeLimit) { 1766 // Not scalar replaceable if the length is not constant or too big. 1767 ptnode_adr(call_idx)->_scalar_replaceable = false; 1768 } 1769 set_escape_state(call_idx, PointsToNode::NoEscape); 1770 add_pointsto_edge(resproj_idx, call_idx); 1771 _processed.set(resproj_idx); 1772 break; 1773 } 1774 1775 case Op_CallStaticJava: 1776 // For a static call, we know exactly what method is being called. 1777 // Use bytecode estimator to record whether the call's return value escapes 1778 { 1779 bool done = true; 1780 const TypeTuple *r = call->tf()->range(); 1781 const Type* ret_type = NULL; 1782 1783 if (r->cnt() > TypeFunc::Parms) 1784 ret_type = r->field_at(TypeFunc::Parms); 1785 1786 // Note: we use isa_ptr() instead of isa_oopptr() here because the 1787 // _multianewarray functions return a TypeRawPtr. 1788 if (ret_type == NULL || ret_type->isa_ptr() == NULL) { 1789 _processed.set(resproj_idx); 1790 break; // doesn't return a pointer type 1791 } 1792 ciMethod *meth = call->as_CallJava()->method(); 1793 const TypeTuple * d = call->tf()->domain(); 1794 if (meth == NULL) { 1795 // not a Java method, assume global escape 1796 set_escape_state(call_idx, PointsToNode::GlobalEscape); 1797 add_pointsto_edge(resproj_idx, _phantom_object); 1798 } else { 1799 BCEscapeAnalyzer *call_analyzer = meth->get_bcea(); 1800 bool copy_dependencies = false; 1801 1802 if (call_analyzer->is_return_allocated()) { 1803 // Returns a newly allocated unescaped object, simply 1804 // update dependency information. 1805 // Mark it as NoEscape so that objects referenced by 1806 // it's fields will be marked as NoEscape at least. 1807 set_escape_state(call_idx, PointsToNode::NoEscape); 1808 add_pointsto_edge(resproj_idx, call_idx); 1809 copy_dependencies = true; 1810 } else if (call_analyzer->is_return_local()) { 1811 // determine whether any arguments are returned 1812 set_escape_state(call_idx, PointsToNode::NoEscape); 1813 for (uint i = TypeFunc::Parms; i < d->cnt(); i++) { 1814 const Type* at = d->field_at(i); 1815 1816 if (at->isa_oopptr() != NULL) { 1817 Node *arg = call->in(i)->uncast(); 1818 1819 if (call_analyzer->is_arg_returned(i - TypeFunc::Parms)) { 1820 PointsToNode *arg_esp = ptnode_adr(arg->_idx); 1821 if (arg_esp->node_type() == PointsToNode::UnknownType) 1822 done = false; 1823 else if (arg_esp->node_type() == PointsToNode::JavaObject) 1824 add_pointsto_edge(resproj_idx, arg->_idx); 1825 else 1826 add_deferred_edge(resproj_idx, arg->_idx); 1827 arg_esp->_hidden_alias = true; 1828 } 1829 } 1830 } 1831 copy_dependencies = true; 1832 } else { 1833 set_escape_state(call_idx, PointsToNode::GlobalEscape); 1834 add_pointsto_edge(resproj_idx, _phantom_object); 1835 for (uint i = TypeFunc::Parms; i < d->cnt(); i++) { 1836 const Type* at = d->field_at(i); 1837 if (at->isa_oopptr() != NULL) { 1838 Node *arg = call->in(i)->uncast(); 1839 PointsToNode *arg_esp = ptnode_adr(arg->_idx); 1840 arg_esp->_hidden_alias = true; 1841 } 1842 } 1843 } 1844 if (copy_dependencies) 1845 call_analyzer->copy_dependencies(_compile->dependencies()); 1846 } 1847 if (done) 1848 _processed.set(resproj_idx); 1849 break; 1850 } 1851 1852 default: 1853 // Some other type of call, assume the worst case that the 1854 // returned value, if any, globally escapes. 1855 { 1856 const TypeTuple *r = call->tf()->range(); 1857 if (r->cnt() > TypeFunc::Parms) { 1858 const Type* ret_type = r->field_at(TypeFunc::Parms); 1859 1860 // Note: we use isa_ptr() instead of isa_oopptr() here because the 1861 // _multianewarray functions return a TypeRawPtr. 1862 if (ret_type->isa_ptr() != NULL) { 1863 set_escape_state(call_idx, PointsToNode::GlobalEscape); 1864 add_pointsto_edge(resproj_idx, _phantom_object); 1865 } 1866 } 1867 _processed.set(resproj_idx); 1868 } 1869 } 1870} 1871 1872// Populate Connection Graph with Ideal nodes and create simple 1873// connection graph edges (do not need to check the node_type of inputs 1874// or to call PointsTo() to walk the connection graph). 1875void ConnectionGraph::record_for_escape_analysis(Node *n, PhaseTransform *phase) { 1876 if (_processed.test(n->_idx)) 1877 return; // No need to redefine node's state. 1878 1879 if (n->is_Call()) { 1880 // Arguments to allocation and locking don't escape. 1881 if (n->is_Allocate()) { 1882 add_node(n, PointsToNode::JavaObject, PointsToNode::UnknownEscape, true); 1883 record_for_optimizer(n); 1884 } else if (n->is_Lock() || n->is_Unlock()) { 1885 // Put Lock and Unlock nodes on IGVN worklist to process them during 1886 // the first IGVN optimization when escape information is still available. 1887 record_for_optimizer(n); 1888 _processed.set(n->_idx); 1889 } else { 1890 // Have to process call's arguments first. 1891 PointsToNode::NodeType nt = PointsToNode::UnknownType; 1892 1893 // Check if a call returns an object. 1894 const TypeTuple *r = n->as_Call()->tf()->range(); 1895 if (n->is_CallStaticJava() && r->cnt() > TypeFunc::Parms && 1896 n->as_Call()->proj_out(TypeFunc::Parms) != NULL) { 1897 // Note: use isa_ptr() instead of isa_oopptr() here because 1898 // the _multianewarray functions return a TypeRawPtr. 1899 if (r->field_at(TypeFunc::Parms)->isa_ptr() != NULL) { 1900 nt = PointsToNode::JavaObject; 1901 } 1902 } 1903 add_node(n, nt, PointsToNode::UnknownEscape, false); 1904 } 1905 return; 1906 } 1907 1908 // Using isa_ptr() instead of isa_oopptr() for LoadP and Phi because 1909 // ThreadLocal has RawPrt type. 1910 switch (n->Opcode()) { 1911 case Op_AddP: 1912 { 1913 add_node(n, PointsToNode::Field, PointsToNode::UnknownEscape, false); 1914 break; 1915 } 1916 case Op_CastX2P: 1917 { // "Unsafe" memory access. 1918 add_node(n, PointsToNode::JavaObject, PointsToNode::GlobalEscape, true); 1919 break; 1920 } 1921 case Op_CastPP: 1922 case Op_CheckCastPP: 1923 case Op_EncodeP: 1924 case Op_DecodeN: 1925 { 1926 add_node(n, PointsToNode::LocalVar, PointsToNode::UnknownEscape, false); 1927 int ti = n->in(1)->_idx; 1928 PointsToNode::NodeType nt = ptnode_adr(ti)->node_type(); 1929 if (nt == PointsToNode::UnknownType) { 1930 _delayed_worklist.push(n); // Process it later. 1931 break; 1932 } else if (nt == PointsToNode::JavaObject) { 1933 add_pointsto_edge(n->_idx, ti); 1934 } else { 1935 add_deferred_edge(n->_idx, ti); 1936 } 1937 _processed.set(n->_idx); 1938 break; 1939 } 1940 case Op_ConP: 1941 { 1942 // assume all pointer constants globally escape except for null 1943 PointsToNode::EscapeState es; 1944 if (phase->type(n) == TypePtr::NULL_PTR) 1945 es = PointsToNode::NoEscape; 1946 else 1947 es = PointsToNode::GlobalEscape; 1948 1949 add_node(n, PointsToNode::JavaObject, es, true); 1950 break; 1951 } 1952 case Op_ConN: 1953 { 1954 // assume all narrow oop constants globally escape except for null 1955 PointsToNode::EscapeState es; 1956 if (phase->type(n) == TypeNarrowOop::NULL_PTR) 1957 es = PointsToNode::NoEscape; 1958 else 1959 es = PointsToNode::GlobalEscape; 1960 1961 add_node(n, PointsToNode::JavaObject, es, true); 1962 break; 1963 } 1964 case Op_CreateEx: 1965 { 1966 // assume that all exception objects globally escape 1967 add_node(n, PointsToNode::JavaObject, PointsToNode::GlobalEscape, true); 1968 break; 1969 } 1970 case Op_LoadKlass: 1971 case Op_LoadNKlass: 1972 { 1973 add_node(n, PointsToNode::JavaObject, PointsToNode::GlobalEscape, true); 1974 break; 1975 } 1976 case Op_LoadP: 1977 case Op_LoadN: 1978 { 1979 const Type *t = phase->type(n); 1980 if (t->make_ptr() == NULL) { 1981 _processed.set(n->_idx); 1982 return; 1983 } 1984 add_node(n, PointsToNode::LocalVar, PointsToNode::UnknownEscape, false); 1985 break; 1986 } 1987 case Op_Parm: 1988 { 1989 _processed.set(n->_idx); // No need to redefine it state. 1990 uint con = n->as_Proj()->_con; 1991 if (con < TypeFunc::Parms) 1992 return; 1993 const Type *t = n->in(0)->as_Start()->_domain->field_at(con); 1994 if (t->isa_ptr() == NULL) 1995 return; 1996 // We have to assume all input parameters globally escape 1997 // (Note: passing 'false' since _processed is already set). 1998 add_node(n, PointsToNode::JavaObject, PointsToNode::GlobalEscape, false); 1999 break; 2000 } 2001 case Op_Phi: 2002 { 2003 const Type *t = n->as_Phi()->type(); 2004 if (t->make_ptr() == NULL) { 2005 // nothing to do if not an oop or narrow oop 2006 _processed.set(n->_idx); 2007 return; 2008 } 2009 add_node(n, PointsToNode::LocalVar, PointsToNode::UnknownEscape, false); 2010 uint i; 2011 for (i = 1; i < n->req() ; i++) { 2012 Node* in = n->in(i); 2013 if (in == NULL) 2014 continue; // ignore NULL 2015 in = in->uncast(); 2016 if (in->is_top() || in == n) 2017 continue; // ignore top or inputs which go back this node 2018 int ti = in->_idx; 2019 PointsToNode::NodeType nt = ptnode_adr(ti)->node_type(); 2020 if (nt == PointsToNode::UnknownType) { 2021 break; 2022 } else if (nt == PointsToNode::JavaObject) { 2023 add_pointsto_edge(n->_idx, ti); 2024 } else { 2025 add_deferred_edge(n->_idx, ti); 2026 } 2027 } 2028 if (i >= n->req()) 2029 _processed.set(n->_idx); 2030 else 2031 _delayed_worklist.push(n); 2032 break; 2033 } 2034 case Op_Proj: 2035 { 2036 // we are only interested in the result projection from a call 2037 if (n->as_Proj()->_con == TypeFunc::Parms && n->in(0)->is_Call() ) { 2038 add_node(n, PointsToNode::LocalVar, PointsToNode::UnknownEscape, false); 2039 process_call_result(n->as_Proj(), phase); 2040 if (!_processed.test(n->_idx)) { 2041 // The call's result may need to be processed later if the call 2042 // returns it's argument and the argument is not processed yet. 2043 _delayed_worklist.push(n); 2044 } 2045 } else { 2046 _processed.set(n->_idx); 2047 } 2048 break; 2049 } 2050 case Op_Return: 2051 { 2052 if( n->req() > TypeFunc::Parms && 2053 phase->type(n->in(TypeFunc::Parms))->isa_oopptr() ) { 2054 // Treat Return value as LocalVar with GlobalEscape escape state. 2055 add_node(n, PointsToNode::LocalVar, PointsToNode::GlobalEscape, false); 2056 int ti = n->in(TypeFunc::Parms)->_idx; 2057 PointsToNode::NodeType nt = ptnode_adr(ti)->node_type(); 2058 if (nt == PointsToNode::UnknownType) { 2059 _delayed_worklist.push(n); // Process it later. 2060 break; 2061 } else if (nt == PointsToNode::JavaObject) { 2062 add_pointsto_edge(n->_idx, ti); 2063 } else { 2064 add_deferred_edge(n->_idx, ti); 2065 } 2066 } 2067 _processed.set(n->_idx); 2068 break; 2069 } 2070 case Op_StoreP: 2071 case Op_StoreN: 2072 { 2073 const Type *adr_type = phase->type(n->in(MemNode::Address)); 2074 adr_type = adr_type->make_ptr(); 2075 if (adr_type->isa_oopptr()) { 2076 add_node(n, PointsToNode::UnknownType, PointsToNode::UnknownEscape, false); 2077 } else { 2078 Node* adr = n->in(MemNode::Address); 2079 if (adr->is_AddP() && phase->type(adr) == TypeRawPtr::NOTNULL && 2080 adr->in(AddPNode::Address)->is_Proj() && 2081 adr->in(AddPNode::Address)->in(0)->is_Allocate()) { 2082 add_node(n, PointsToNode::UnknownType, PointsToNode::UnknownEscape, false); 2083 // We are computing a raw address for a store captured 2084 // by an Initialize compute an appropriate address type. 2085 int offs = (int)phase->find_intptr_t_con(adr->in(AddPNode::Offset), Type::OffsetBot); 2086 assert(offs != Type::OffsetBot, "offset must be a constant"); 2087 } else { 2088 _processed.set(n->_idx); 2089 return; 2090 } 2091 } 2092 break; 2093 } 2094 case Op_StorePConditional: 2095 case Op_CompareAndSwapP: 2096 case Op_CompareAndSwapN: 2097 { 2098 const Type *adr_type = phase->type(n->in(MemNode::Address)); 2099 adr_type = adr_type->make_ptr(); 2100 if (adr_type->isa_oopptr()) { 2101 add_node(n, PointsToNode::UnknownType, PointsToNode::UnknownEscape, false); 2102 } else { 2103 _processed.set(n->_idx); 2104 return; 2105 } 2106 break; 2107 } 2108 case Op_ThreadLocal: 2109 { 2110 add_node(n, PointsToNode::JavaObject, PointsToNode::ArgEscape, true); 2111 break; 2112 } 2113 default: 2114 ; 2115 // nothing to do 2116 } 2117 return; 2118} 2119 2120void ConnectionGraph::build_connection_graph(Node *n, PhaseTransform *phase) { 2121 uint n_idx = n->_idx; 2122 2123 // Don't set processed bit for AddP, LoadP, StoreP since 2124 // they may need more then one pass to process. 2125 if (_processed.test(n_idx)) 2126 return; // No need to redefine node's state. 2127 2128 if (n->is_Call()) { 2129 CallNode *call = n->as_Call(); 2130 process_call_arguments(call, phase); 2131 _processed.set(n_idx); 2132 return; 2133 } 2134 2135 switch (n->Opcode()) { 2136 case Op_AddP: 2137 { 2138 Node *base = get_addp_base(n); 2139 // Create a field edge to this node from everything base could point to. 2140 VectorSet ptset(Thread::current()->resource_area()); 2141 PointsTo(ptset, base, phase); 2142 for( VectorSetI i(&ptset); i.test(); ++i ) { 2143 uint pt = i.elem; 2144 add_field_edge(pt, n_idx, address_offset(n, phase)); 2145 } 2146 break; 2147 } 2148 case Op_CastX2P: 2149 { 2150 assert(false, "Op_CastX2P"); 2151 break; 2152 } 2153 case Op_CastPP: 2154 case Op_CheckCastPP: 2155 case Op_EncodeP: 2156 case Op_DecodeN: 2157 { 2158 int ti = n->in(1)->_idx; 2159 if (ptnode_adr(ti)->node_type() == PointsToNode::JavaObject) { 2160 add_pointsto_edge(n_idx, ti); 2161 } else { 2162 add_deferred_edge(n_idx, ti); 2163 } 2164 _processed.set(n_idx); 2165 break; 2166 } 2167 case Op_ConP: 2168 { 2169 assert(false, "Op_ConP"); 2170 break; 2171 } 2172 case Op_ConN: 2173 { 2174 assert(false, "Op_ConN"); 2175 break; 2176 } 2177 case Op_CreateEx: 2178 { 2179 assert(false, "Op_CreateEx"); 2180 break; 2181 } 2182 case Op_LoadKlass: 2183 case Op_LoadNKlass: 2184 { 2185 assert(false, "Op_LoadKlass"); 2186 break; 2187 } 2188 case Op_LoadP: 2189 case Op_LoadN: 2190 { 2191 const Type *t = phase->type(n); 2192#ifdef ASSERT 2193 if (t->make_ptr() == NULL) 2194 assert(false, "Op_LoadP"); 2195#endif 2196 2197 Node* adr = n->in(MemNode::Address)->uncast(); 2198 const Type *adr_type = phase->type(adr); 2199 Node* adr_base; 2200 if (adr->is_AddP()) { 2201 adr_base = get_addp_base(adr); 2202 } else { 2203 adr_base = adr; 2204 } 2205 2206 // For everything "adr_base" could point to, create a deferred edge from 2207 // this node to each field with the same offset. 2208 VectorSet ptset(Thread::current()->resource_area()); 2209 PointsTo(ptset, adr_base, phase); 2210 int offset = address_offset(adr, phase); 2211 for( VectorSetI i(&ptset); i.test(); ++i ) { 2212 uint pt = i.elem; 2213 add_deferred_edge_to_fields(n_idx, pt, offset); 2214 } 2215 break; 2216 } 2217 case Op_Parm: 2218 { 2219 assert(false, "Op_Parm"); 2220 break; 2221 } 2222 case Op_Phi: 2223 { 2224#ifdef ASSERT 2225 const Type *t = n->as_Phi()->type(); 2226 if (t->make_ptr() == NULL) 2227 assert(false, "Op_Phi"); 2228#endif 2229 for (uint i = 1; i < n->req() ; i++) { 2230 Node* in = n->in(i); 2231 if (in == NULL) 2232 continue; // ignore NULL 2233 in = in->uncast(); 2234 if (in->is_top() || in == n) 2235 continue; // ignore top or inputs which go back this node 2236 int ti = in->_idx; 2237 if (ptnode_adr(in->_idx)->node_type() == PointsToNode::JavaObject) { 2238 add_pointsto_edge(n_idx, ti); 2239 } else { 2240 add_deferred_edge(n_idx, ti); 2241 } 2242 } 2243 _processed.set(n_idx); 2244 break; 2245 } 2246 case Op_Proj: 2247 { 2248 // we are only interested in the result projection from a call 2249 if (n->as_Proj()->_con == TypeFunc::Parms && n->in(0)->is_Call() ) { 2250 process_call_result(n->as_Proj(), phase); 2251 assert(_processed.test(n_idx), "all call results should be processed"); 2252 } else { 2253 assert(false, "Op_Proj"); 2254 } 2255 break; 2256 } 2257 case Op_Return: 2258 { 2259#ifdef ASSERT 2260 if( n->req() <= TypeFunc::Parms || 2261 !phase->type(n->in(TypeFunc::Parms))->isa_oopptr() ) { 2262 assert(false, "Op_Return"); 2263 } 2264#endif 2265 int ti = n->in(TypeFunc::Parms)->_idx; 2266 if (ptnode_adr(ti)->node_type() == PointsToNode::JavaObject) { 2267 add_pointsto_edge(n_idx, ti); 2268 } else { 2269 add_deferred_edge(n_idx, ti); 2270 } 2271 _processed.set(n_idx); 2272 break; 2273 } 2274 case Op_StoreP: 2275 case Op_StoreN: 2276 case Op_StorePConditional: 2277 case Op_CompareAndSwapP: 2278 case Op_CompareAndSwapN: 2279 { 2280 Node *adr = n->in(MemNode::Address); 2281 const Type *adr_type = phase->type(adr)->make_ptr(); 2282#ifdef ASSERT 2283 if (!adr_type->isa_oopptr()) 2284 assert(phase->type(adr) == TypeRawPtr::NOTNULL, "Op_StoreP"); 2285#endif 2286 2287 assert(adr->is_AddP(), "expecting an AddP"); 2288 Node *adr_base = get_addp_base(adr); 2289 Node *val = n->in(MemNode::ValueIn)->uncast(); 2290 // For everything "adr_base" could point to, create a deferred edge 2291 // to "val" from each field with the same offset. 2292 VectorSet ptset(Thread::current()->resource_area()); 2293 PointsTo(ptset, adr_base, phase); 2294 for( VectorSetI i(&ptset); i.test(); ++i ) { 2295 uint pt = i.elem; 2296 add_edge_from_fields(pt, val->_idx, address_offset(adr, phase)); 2297 } 2298 break; 2299 } 2300 case Op_ThreadLocal: 2301 { 2302 assert(false, "Op_ThreadLocal"); 2303 break; 2304 } 2305 default: 2306 ; 2307 // nothing to do 2308 } 2309} 2310 2311#ifndef PRODUCT 2312void ConnectionGraph::dump() { 2313 PhaseGVN *igvn = _compile->initial_gvn(); 2314 bool first = true; 2315 2316 uint size = nodes_size(); 2317 for (uint ni = 0; ni < size; ni++) { 2318 PointsToNode *ptn = ptnode_adr(ni); 2319 PointsToNode::NodeType ptn_type = ptn->node_type(); 2320 2321 if (ptn_type != PointsToNode::JavaObject || ptn->_node == NULL) 2322 continue; 2323 PointsToNode::EscapeState es = escape_state(ptn->_node, igvn); 2324 if (ptn->_node->is_Allocate() && (es == PointsToNode::NoEscape || Verbose)) { 2325 if (first) { 2326 tty->cr(); 2327 tty->print("======== Connection graph for "); 2328 _compile->method()->print_short_name(); 2329 tty->cr(); 2330 first = false; 2331 } 2332 tty->print("%6d ", ni); 2333 ptn->dump(); 2334 // Print all locals which reference this allocation 2335 for (uint li = ni; li < size; li++) { 2336 PointsToNode *ptn_loc = ptnode_adr(li); 2337 PointsToNode::NodeType ptn_loc_type = ptn_loc->node_type(); 2338 if ( ptn_loc_type == PointsToNode::LocalVar && ptn_loc->_node != NULL && 2339 ptn_loc->edge_count() == 1 && ptn_loc->edge_target(0) == ni ) { 2340 ptnode_adr(li)->dump(false); 2341 } 2342 } 2343 if (Verbose) { 2344 // Print all fields which reference this allocation 2345 for (uint i = 0; i < ptn->edge_count(); i++) { 2346 uint ei = ptn->edge_target(i); 2347 ptnode_adr(ei)->dump(false); 2348 } 2349 } 2350 tty->cr(); 2351 } 2352 } 2353} 2354#endif 2355