1 /* 2 * Copyright (c) 2015, 2018, Oracle and/or its affiliates. All rights reserved. 3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. 4 * 5 * This code is free software; you can redistribute it and/or modify it 6 * under the terms of the GNU General Public License version 2 only, as 7 * published by the Free Software Foundation. 8 * 9 * This code is distributed in the hope that it will be useful, but WITHOUT 10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 12 * version 2 for more details (a copy is included in the LICENSE file that 13 * accompanied this code). 14 * 15 * You should have received a copy of the GNU General Public License version 16 * 2 along with this work; if not, write to the Free Software Foundation, 17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. 18 * 19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA 20 * or visit www.oracle.com if you need additional information or have any 21 * questions. 22 */ 23 24 #include "precompiled.hpp" 25 #include "opto/compile.hpp" 26 #include "opto/castnode.hpp" 27 #include "opto/escape.hpp" 28 #include "opto/graphKit.hpp" 29 #include "opto/idealKit.hpp" 30 #include "opto/loopnode.hpp" 31 #include "opto/macro.hpp" 32 #include "opto/node.hpp" 33 #include "opto/type.hpp" 34 #include "utilities/macros.hpp" 35 #include "gc/z/c2/zBarrierSetC2.hpp" 36 #include "gc/z/zThreadLocalData.hpp" 37 #include "gc/z/zBarrierSetRuntime.hpp" 38 39 ZBarrierSetC2State::ZBarrierSetC2State(Arena* comp_arena) 40 : _load_barrier_nodes(new (comp_arena) GrowableArray<LoadBarrierNode*>(comp_arena, 8, 0, NULL)) {} 41 42 int ZBarrierSetC2State::load_barrier_count() const { 43 return _load_barrier_nodes->length(); 44 } 45 46 void ZBarrierSetC2State::add_load_barrier_node(LoadBarrierNode * n) { 47 assert(!_load_barrier_nodes->contains(n), " duplicate entry in expand list"); 48 _load_barrier_nodes->append(n); 49 } 50 51 void ZBarrierSetC2State::remove_load_barrier_node(LoadBarrierNode * n) { 52 // this function may be called twice for a node so check 53 // that the node is in the array before attempting to remove it 54 if (_load_barrier_nodes->contains(n)) { 55 _load_barrier_nodes->remove(n); 56 } 57 } 58 59 LoadBarrierNode* ZBarrierSetC2State::load_barrier_node(int idx) const { 60 return _load_barrier_nodes->at(idx); 61 } 62 63 void* ZBarrierSetC2::create_barrier_state(Arena* comp_arena) const { 64 return new(comp_arena) ZBarrierSetC2State(comp_arena); 65 } 66 67 ZBarrierSetC2State* ZBarrierSetC2::state() const { 68 return reinterpret_cast<ZBarrierSetC2State*>(Compile::current()->barrier_set_state()); 69 } 70 71 bool ZBarrierSetC2::is_gc_barrier_node(Node* node) const { 72 // 1. This step follows potential oop projections of a load barrier before expansion 73 if (node->is_Proj()) { 74 node = node->in(0); 75 } 76 77 // 2. This step checks for unexpanded load barriers 78 if (node->is_LoadBarrier()) { 79 return true; 80 } 81 82 // 3. This step checks for the phi corresponding to an optimized load barrier expansion 83 if (node->is_Phi()) { 84 PhiNode* phi = node->as_Phi(); 85 Node* n = phi->in(1); 86 if (n != NULL && (n->is_LoadBarrierSlowReg() || n->is_LoadBarrierWeakSlowReg())) { 87 return true; 88 } 89 } 90 91 return false; 92 } 93 94 void ZBarrierSetC2::register_potential_barrier_node(Node* node) const { 95 if (node->is_LoadBarrier()) { 96 state()->add_load_barrier_node(node->as_LoadBarrier()); 97 } 98 } 99 100 void ZBarrierSetC2::unregister_potential_barrier_node(Node* node) const { 101 if (node->is_LoadBarrier()) { 102 state()->remove_load_barrier_node(node->as_LoadBarrier()); 103 } 104 } 105 106 void ZBarrierSetC2::eliminate_useless_gc_barriers(Unique_Node_List &useful, Compile* C) const { 107 // Remove useless LoadBarrier nodes 108 ZBarrierSetC2State* s = state(); 109 for (int i = s->load_barrier_count()-1; i >= 0; i--) { 110 LoadBarrierNode* n = s->load_barrier_node(i); 111 if (!useful.member(n)) { 112 unregister_potential_barrier_node(n); 113 } 114 } 115 } 116 117 void ZBarrierSetC2::enqueue_useful_gc_barrier(PhaseIterGVN* igvn, Node* node) const { 118 if (node->is_LoadBarrier() && !node->as_LoadBarrier()->has_true_uses()) { 119 igvn->_worklist.push(node); 120 } 121 } 122 123 void ZBarrierSetC2::find_dominating_barriers(PhaseIterGVN& igvn) { 124 // Look for dominating barriers on the same address only once all 125 // other loop opts are over: loop opts may cause a safepoint to be 126 // inserted between a barrier and its dominating barrier. 127 Compile* C = Compile::current(); 128 ZBarrierSetC2* bs = (ZBarrierSetC2*)BarrierSet::barrier_set()->barrier_set_c2(); 129 ZBarrierSetC2State* s = bs->state(); 130 if (s->load_barrier_count() >= 2) { 131 Compile::TracePhase tp("idealLoop", &C->timers[Phase::_t_idealLoop]); 132 PhaseIdealLoop ideal_loop(igvn, LoopOptsLastRound); 133 if (C->major_progress()) C->print_method(PHASE_PHASEIDEALLOOP_ITERATIONS, 2); 134 } 135 } 136 137 void ZBarrierSetC2::add_users_to_worklist(Unique_Node_List* worklist) const { 138 // Permanent temporary workaround 139 // Loadbarriers may have non-obvious dead uses keeping them alive during parsing. The use is 140 // removed by RemoveUseless (after parsing, before optimize) but the barriers won't be added to 141 // the worklist. Unless we add them explicitly they are not guaranteed to end up there. 142 ZBarrierSetC2State* s = state(); 143 144 for (int i = 0; i < s->load_barrier_count(); i++) { 145 LoadBarrierNode* n = s->load_barrier_node(i); 146 worklist->push(n); 147 } 148 } 149 150 const TypeFunc* ZBarrierSetC2::load_barrier_Type() const { 151 const Type** fields; 152 153 // Create input types (domain) 154 fields = TypeTuple::fields(2); 155 fields[TypeFunc::Parms+0] = TypeInstPtr::NOTNULL; 156 fields[TypeFunc::Parms+1] = TypeOopPtr::BOTTOM; 157 const TypeTuple *domain = TypeTuple::make(TypeFunc::Parms+2, fields); 158 159 // Create result type (range) 160 fields = TypeTuple::fields(1); 161 fields[TypeFunc::Parms+0] = TypeInstPtr::BOTTOM; 162 const TypeTuple *range = TypeTuple::make(TypeFunc::Parms+1, fields); 163 164 return TypeFunc::make(domain, range); 165 } 166 167 // == LoadBarrierNode == 168 169 LoadBarrierNode::LoadBarrierNode(Compile* C, 170 Node* c, 171 Node* mem, 172 Node* val, 173 Node* adr, 174 bool weak, 175 bool writeback, 176 bool oop_reload_allowed) : 177 MultiNode(Number_of_Inputs), 178 _weak(weak), 179 _writeback(writeback), 180 _oop_reload_allowed(oop_reload_allowed) { 181 init_req(Control, c); 182 init_req(Memory, mem); 183 init_req(Oop, val); 184 init_req(Address, adr); 185 init_req(Similar, C->top()); 186 187 init_class_id(Class_LoadBarrier); 188 BarrierSetC2* bs = BarrierSet::barrier_set()->barrier_set_c2(); 189 bs->register_potential_barrier_node(this); 190 } 191 192 const Type *LoadBarrierNode::bottom_type() const { 193 const Type** floadbarrier = (const Type **)(Compile::current()->type_arena()->Amalloc_4((Number_of_Outputs)*sizeof(Type*))); 194 Node* in_oop = in(Oop); 195 floadbarrier[Control] = Type::CONTROL; 196 floadbarrier[Memory] = Type::MEMORY; 197 floadbarrier[Oop] = in_oop == NULL ? Type::TOP : in_oop->bottom_type(); 198 return TypeTuple::make(Number_of_Outputs, floadbarrier); 199 } 200 201 const Type *LoadBarrierNode::Value(PhaseGVN *phase) const { 202 const Type** floadbarrier = (const Type **)(phase->C->type_arena()->Amalloc_4((Number_of_Outputs)*sizeof(Type*))); 203 const Type* val_t = phase->type(in(Oop)); 204 floadbarrier[Control] = Type::CONTROL; 205 floadbarrier[Memory] = Type::MEMORY; 206 floadbarrier[Oop] = val_t; 207 return TypeTuple::make(Number_of_Outputs, floadbarrier); 208 } 209 210 bool LoadBarrierNode::is_dominator(PhaseIdealLoop* phase, bool linear_only, Node *d, Node *n) { 211 if (phase != NULL) { 212 return phase->is_dominator(d, n); 213 } 214 215 for (int i = 0; i < 10 && n != NULL; i++) { 216 n = IfNode::up_one_dom(n, linear_only); 217 if (n == d) { 218 return true; 219 } 220 } 221 222 return false; 223 } 224 225 LoadBarrierNode* LoadBarrierNode::has_dominating_barrier(PhaseIdealLoop* phase, bool linear_only, bool look_for_similar) { 226 Node* val = in(LoadBarrierNode::Oop); 227 if (in(Similar)->is_Proj() && in(Similar)->in(0)->is_LoadBarrier()) { 228 LoadBarrierNode* lb = in(Similar)->in(0)->as_LoadBarrier(); 229 assert(lb->in(Address) == in(Address), ""); 230 // Load barrier on Similar edge dominates so if it now has the Oop field it can replace this barrier. 231 if (lb->in(Oop) == in(Oop)) { 232 return lb; 233 } 234 // Follow chain of load barrier through Similar edges 235 while (!lb->in(Similar)->is_top()) { 236 lb = lb->in(Similar)->in(0)->as_LoadBarrier(); 237 assert(lb->in(Address) == in(Address), ""); 238 } 239 if (lb != in(Similar)->in(0)) { 240 return lb; 241 } 242 } 243 for (DUIterator_Fast imax, i = val->fast_outs(imax); i < imax; i++) { 244 Node* u = val->fast_out(i); 245 if (u != this && u->is_LoadBarrier() && u->in(Oop) == val && u->as_LoadBarrier()->has_true_uses()) { 246 Node* this_ctrl = in(LoadBarrierNode::Control); 247 Node* other_ctrl = u->in(LoadBarrierNode::Control); 248 if (is_dominator(phase, linear_only, other_ctrl, this_ctrl)) { 249 return u->as_LoadBarrier(); 250 } 251 } 252 } 253 254 if (ZVerifyLoadBarriers || can_be_eliminated()) { 255 return NULL; 256 } 257 258 if (!look_for_similar) { 259 return NULL; 260 } 261 262 Node* addr = in(LoadBarrierNode::Address); 263 for (DUIterator_Fast imax, i = addr->fast_outs(imax); i < imax; i++) { 264 Node* u = addr->fast_out(i); 265 if (u != this && u->is_LoadBarrier() && u->as_LoadBarrier()->has_true_uses()) { 266 Node* this_ctrl = in(LoadBarrierNode::Control); 267 Node* other_ctrl = u->in(LoadBarrierNode::Control); 268 if (is_dominator(phase, linear_only, other_ctrl, this_ctrl)) { 269 ResourceMark rm; 270 Unique_Node_List wq; 271 wq.push(in(LoadBarrierNode::Control)); 272 bool ok = true; 273 bool dom_found = false; 274 for (uint next = 0; next < wq.size(); ++next) { 275 Node *n = wq.at(next); 276 if (n->is_top()) { 277 return NULL; 278 } 279 assert(n->is_CFG(), ""); 280 if (n->is_SafePoint()) { 281 ok = false; 282 break; 283 } 284 if (n == u) { 285 dom_found = true; 286 continue; 287 } 288 if (n->is_Region()) { 289 for (uint i = 1; i < n->req(); i++) { 290 Node* m = n->in(i); 291 if (m != NULL) { 292 wq.push(m); 293 } 294 } 295 } else { 296 Node* m = n->in(0); 297 if (m != NULL) { 298 wq.push(m); 299 } 300 } 301 } 302 if (ok) { 303 assert(dom_found, ""); 304 return u->as_LoadBarrier();; 305 } 306 break; 307 } 308 } 309 } 310 311 return NULL; 312 } 313 314 void LoadBarrierNode::push_dominated_barriers(PhaseIterGVN* igvn) const { 315 // Change to that barrier may affect a dominated barrier so re-push those 316 Node* val = in(LoadBarrierNode::Oop); 317 318 for (DUIterator_Fast imax, i = val->fast_outs(imax); i < imax; i++) { 319 Node* u = val->fast_out(i); 320 if (u != this && u->is_LoadBarrier() && u->in(Oop) == val) { 321 Node* this_ctrl = in(Control); 322 Node* other_ctrl = u->in(Control); 323 if (is_dominator(NULL, false, this_ctrl, other_ctrl)) { 324 igvn->_worklist.push(u); 325 } 326 } 327 328 Node* addr = in(LoadBarrierNode::Address); 329 for (DUIterator_Fast imax, i = addr->fast_outs(imax); i < imax; i++) { 330 Node* u = addr->fast_out(i); 331 if (u != this && u->is_LoadBarrier() && u->in(Similar)->is_top()) { 332 Node* this_ctrl = in(Control); 333 Node* other_ctrl = u->in(Control); 334 if (is_dominator(NULL, false, this_ctrl, other_ctrl)) { 335 igvn->_worklist.push(u); 336 } 337 } 338 } 339 } 340 } 341 342 Node *LoadBarrierNode::Identity(PhaseGVN *phase) { 343 if (!phase->C->directive()->ZOptimizeLoadBarriersOption) { 344 return this; 345 } 346 347 bool redundant_addr = false; 348 LoadBarrierNode* dominating_barrier = has_dominating_barrier(NULL, true, false); 349 if (dominating_barrier != NULL) { 350 assert(dominating_barrier->in(Oop) == in(Oop), ""); 351 return dominating_barrier; 352 } 353 354 return this; 355 } 356 357 Node *LoadBarrierNode::Ideal(PhaseGVN *phase, bool can_reshape) { 358 if (remove_dead_region(phase, can_reshape)) { 359 return this; 360 } 361 362 Node* val = in(Oop); 363 Node* mem = in(Memory); 364 Node* ctrl = in(Control); 365 Node* adr = in(Address); 366 assert(val->Opcode() != Op_LoadN, ""); 367 368 if (mem->is_MergeMem()) { 369 Node* new_mem = mem->as_MergeMem()->memory_at(Compile::AliasIdxRaw); 370 set_req(Memory, new_mem); 371 if (mem->outcnt() == 0 && can_reshape) { 372 phase->is_IterGVN()->_worklist.push(mem); 373 } 374 375 return this; 376 } 377 378 bool optimizeLoadBarriers = phase->C->directive()->ZOptimizeLoadBarriersOption; 379 LoadBarrierNode* dominating_barrier = optimizeLoadBarriers ? has_dominating_barrier(NULL, !can_reshape, !phase->C->major_progress()) : NULL; 380 if (dominating_barrier != NULL && dominating_barrier->in(Oop) != in(Oop)) { 381 assert(in(Address) == dominating_barrier->in(Address), ""); 382 set_req(Similar, dominating_barrier->proj_out(Oop)); 383 return this; 384 } 385 386 bool eliminate = (optimizeLoadBarriers && !(val->is_Phi() || val->Opcode() == Op_LoadP || val->Opcode() == Op_GetAndSetP || val->is_DecodeN())) || 387 (can_reshape && (dominating_barrier != NULL || !has_true_uses())); 388 389 if (eliminate) { 390 if (can_reshape) { 391 PhaseIterGVN* igvn = phase->is_IterGVN(); 392 Node* out_ctrl = proj_out_or_null(Control); 393 Node* out_res = proj_out_or_null(Oop); 394 395 if (out_ctrl != NULL) { 396 igvn->replace_node(out_ctrl, ctrl); 397 } 398 399 // That transformation may cause the Similar edge on the load barrier to be invalid 400 fix_similar_in_uses(igvn); 401 if (out_res != NULL) { 402 if (dominating_barrier != NULL) { 403 igvn->replace_node(out_res, dominating_barrier->proj_out(Oop)); 404 } else { 405 igvn->replace_node(out_res, val); 406 } 407 } 408 } 409 410 return new ConINode(TypeInt::ZERO); 411 } 412 413 // If the Similar edge is no longer a load barrier, clear it 414 Node* similar = in(Similar); 415 if (!similar->is_top() && !(similar->is_Proj() && similar->in(0)->is_LoadBarrier())) { 416 set_req(Similar, phase->C->top()); 417 return this; 418 } 419 420 if (can_reshape) { 421 // If this barrier is linked through the Similar edge by a 422 // dominated barrier and both barriers have the same Oop field, 423 // the dominated barrier can go away, so push it for reprocessing. 424 // We also want to avoid a barrier to depend on another dominating 425 // barrier through its Similar edge that itself depend on another 426 // barrier through its Similar edge and rather have the first 427 // depend on the third. 428 PhaseIterGVN* igvn = phase->is_IterGVN(); 429 Node* out_res = proj_out(Oop); 430 for (DUIterator_Fast imax, i = out_res->fast_outs(imax); i < imax; i++) { 431 Node* u = out_res->fast_out(i); 432 if (u->is_LoadBarrier() && u->in(Similar) == out_res && 433 (u->in(Oop) == val || !u->in(Similar)->is_top())) { 434 igvn->_worklist.push(u); 435 } 436 } 437 438 push_dominated_barriers(igvn); 439 } 440 441 return NULL; 442 } 443 444 void LoadBarrierNode::fix_similar_in_uses(PhaseIterGVN* igvn) { 445 Node* out_res = proj_out_or_null(Oop); 446 if (out_res == NULL) { 447 return; 448 } 449 450 for (DUIterator_Fast imax, i = out_res->fast_outs(imax); i < imax; i++) { 451 Node* u = out_res->fast_out(i); 452 if (u->is_LoadBarrier() && u->in(Similar) == out_res) { 453 igvn->replace_input_of(u, Similar, igvn->C->top()); 454 --i; 455 --imax; 456 } 457 } 458 } 459 460 bool LoadBarrierNode::has_true_uses() const { 461 Node* out_res = proj_out_or_null(Oop); 462 if (out_res == NULL) { 463 return false; 464 } 465 466 for (DUIterator_Fast imax, i = out_res->fast_outs(imax); i < imax; i++) { 467 Node* u = out_res->fast_out(i); 468 if (!u->is_LoadBarrier() || u->in(Similar) != out_res) { 469 return true; 470 } 471 } 472 473 return false; 474 } 475 476 // == Accesses == 477 478 Node* ZBarrierSetC2::make_cas_loadbarrier(C2AtomicParseAccess& access) const { 479 assert(!UseCompressedOops, "Not allowed"); 480 CompareAndSwapNode* cas = (CompareAndSwapNode*)access.raw_access(); 481 PhaseGVN& gvn = access.gvn(); 482 Compile* C = Compile::current(); 483 GraphKit* kit = access.kit(); 484 485 Node* in_ctrl = cas->in(MemNode::Control); 486 Node* in_mem = cas->in(MemNode::Memory); 487 Node* in_adr = cas->in(MemNode::Address); 488 Node* in_val = cas->in(MemNode::ValueIn); 489 Node* in_expected = cas->in(LoadStoreConditionalNode::ExpectedIn); 490 491 float likely = PROB_LIKELY(0.999); 492 493 const TypePtr *adr_type = gvn.type(in_adr)->isa_ptr(); 494 Compile::AliasType* alias_type = C->alias_type(adr_type); 495 int alias_idx = C->get_alias_index(adr_type); 496 497 // Outer check - true: continue, false: load and check 498 Node* region = new RegionNode(3); 499 Node* phi = new PhiNode(region, TypeInt::BOOL); 500 Node* phi_mem = new PhiNode(region, Type::MEMORY, adr_type); 501 502 // Inner check - is the healed ref equal to the expected 503 Node* region2 = new RegionNode(3); 504 Node* phi2 = new PhiNode(region2, TypeInt::BOOL); 505 Node* phi_mem2 = new PhiNode(region2, Type::MEMORY, adr_type); 506 507 // CAS node returns 0 or 1 508 Node* cmp = gvn.transform(new CmpINode(cas, kit->intcon(0))); 509 Node* bol = gvn.transform(new BoolNode(cmp, BoolTest::ne))->as_Bool(); 510 IfNode* iff = gvn.transform(new IfNode(in_ctrl, bol, likely, COUNT_UNKNOWN))->as_If(); 511 Node* then = gvn.transform(new IfTrueNode(iff)); 512 Node* elsen = gvn.transform(new IfFalseNode(iff)); 513 514 Node* scmemproj1 = gvn.transform(new SCMemProjNode(cas)); 515 516 kit->set_memory(scmemproj1, alias_idx); 517 phi_mem->init_req(1, scmemproj1); 518 phi_mem2->init_req(2, scmemproj1); 519 520 // CAS fail - reload and heal oop 521 Node* reload = kit->make_load(elsen, in_adr, TypeOopPtr::BOTTOM, T_OBJECT, MemNode::unordered); 522 Node* barrier = gvn.transform(new LoadBarrierNode(C, elsen, scmemproj1, reload, in_adr, false, true, false)); 523 Node* barrierctrl = gvn.transform(new ProjNode(barrier, LoadBarrierNode::Control)); 524 Node* barrierdata = gvn.transform(new ProjNode(barrier, LoadBarrierNode::Oop)); 525 526 // Check load 527 Node* tmpX = gvn.transform(new CastP2XNode(NULL, barrierdata)); 528 Node* in_expX = gvn.transform(new CastP2XNode(NULL, in_expected)); 529 Node* cmp2 = gvn.transform(new CmpXNode(tmpX, in_expX)); 530 Node *bol2 = gvn.transform(new BoolNode(cmp2, BoolTest::ne))->as_Bool(); 531 IfNode* iff2 = gvn.transform(new IfNode(barrierctrl, bol2, likely, COUNT_UNKNOWN))->as_If(); 532 Node* then2 = gvn.transform(new IfTrueNode(iff2)); 533 Node* elsen2 = gvn.transform(new IfFalseNode(iff2)); 534 535 // redo CAS 536 Node* cas2 = gvn.transform(new CompareAndSwapPNode(elsen2, kit->memory(alias_idx), in_adr, in_val, in_expected, cas->order())); 537 Node* scmemproj2 = gvn.transform(new SCMemProjNode(cas2)); 538 kit->set_control(elsen2); 539 kit->set_memory(scmemproj2, alias_idx); 540 541 // Merge inner flow - check if healed oop was equal too expected. 542 region2->set_req(1, kit->control()); 543 region2->set_req(2, then2); 544 phi2->set_req(1, cas2); 545 phi2->set_req(2, kit->intcon(0)); 546 phi_mem2->init_req(1, scmemproj2); 547 kit->set_memory(phi_mem2, alias_idx); 548 549 // Merge outer flow - then check if first CAS succeeded 550 region->set_req(1, then); 551 region->set_req(2, region2); 552 phi->set_req(1, kit->intcon(1)); 553 phi->set_req(2, phi2); 554 phi_mem->init_req(2, phi_mem2); 555 kit->set_memory(phi_mem, alias_idx); 556 557 gvn.transform(region2); 558 gvn.transform(phi2); 559 gvn.transform(phi_mem2); 560 gvn.transform(region); 561 gvn.transform(phi); 562 gvn.transform(phi_mem); 563 564 kit->set_control(region); 565 kit->insert_mem_bar(Op_MemBarCPUOrder); 566 567 return phi; 568 } 569 570 Node* ZBarrierSetC2::make_cmpx_loadbarrier(C2AtomicParseAccess& access) const { 571 CompareAndExchangePNode* cmpx = (CompareAndExchangePNode*)access.raw_access(); 572 GraphKit* kit = access.kit(); 573 PhaseGVN& gvn = kit->gvn(); 574 Compile* C = Compile::current(); 575 576 Node* in_ctrl = cmpx->in(MemNode::Control); 577 Node* in_mem = cmpx->in(MemNode::Memory); 578 Node* in_adr = cmpx->in(MemNode::Address); 579 Node* in_val = cmpx->in(MemNode::ValueIn); 580 Node* in_expected = cmpx->in(LoadStoreConditionalNode::ExpectedIn); 581 582 float likely = PROB_LIKELY(0.999); 583 584 const TypePtr *adr_type = cmpx->get_ptr_type(); 585 Compile::AliasType* alias_type = C->alias_type(adr_type); 586 int alias_idx = C->get_alias_index(adr_type); 587 588 // Outer check - true: continue, false: load and check 589 Node* region = new RegionNode(3); 590 Node* phi = new PhiNode(region, adr_type); 591 592 // Inner check - is the healed ref equal to the expected 593 Node* region2 = new RegionNode(3); 594 Node* phi2 = new PhiNode(region2, adr_type); 595 596 // Check if cmpx succeeded 597 Node* cmp = gvn.transform(new CmpPNode(cmpx, in_expected)); 598 Node* bol = gvn.transform(new BoolNode(cmp, BoolTest::eq))->as_Bool(); 599 IfNode* iff = gvn.transform(new IfNode(in_ctrl, bol, likely, COUNT_UNKNOWN))->as_If(); 600 Node* then = gvn.transform(new IfTrueNode(iff)); 601 Node* elsen = gvn.transform(new IfFalseNode(iff)); 602 603 Node* scmemproj1 = gvn.transform(new SCMemProjNode(cmpx)); 604 kit->set_memory(scmemproj1, alias_idx); 605 606 // CAS fail - reload and heal oop 607 Node* reload = kit->make_load(elsen, in_adr, TypeOopPtr::BOTTOM, T_OBJECT, MemNode::unordered); 608 Node* barrier = gvn.transform(new LoadBarrierNode(C, elsen, scmemproj1, reload, in_adr, false, true, false)); 609 Node* barrierctrl = gvn.transform(new ProjNode(barrier, LoadBarrierNode::Control)); 610 Node* barrierdata = gvn.transform(new ProjNode(barrier, LoadBarrierNode::Oop)); 611 612 // Check load 613 Node* tmpX = gvn.transform(new CastP2XNode(NULL, barrierdata)); 614 Node* in_expX = gvn.transform(new CastP2XNode(NULL, in_expected)); 615 Node* cmp2 = gvn.transform(new CmpXNode(tmpX, in_expX)); 616 Node *bol2 = gvn.transform(new BoolNode(cmp2, BoolTest::ne))->as_Bool(); 617 IfNode* iff2 = gvn.transform(new IfNode(barrierctrl, bol2, likely, COUNT_UNKNOWN))->as_If(); 618 Node* then2 = gvn.transform(new IfTrueNode(iff2)); 619 Node* elsen2 = gvn.transform(new IfFalseNode(iff2)); 620 621 // Redo CAS 622 Node* cmpx2 = gvn.transform(new CompareAndExchangePNode(elsen2, kit->memory(alias_idx), in_adr, in_val, in_expected, adr_type, cmpx->get_ptr_type(), cmpx->order())); 623 Node* scmemproj2 = gvn.transform(new SCMemProjNode(cmpx2)); 624 kit->set_control(elsen2); 625 kit->set_memory(scmemproj2, alias_idx); 626 627 // Merge inner flow - check if healed oop was equal too expected. 628 region2->set_req(1, kit->control()); 629 region2->set_req(2, then2); 630 phi2->set_req(1, cmpx2); 631 phi2->set_req(2, barrierdata); 632 633 // Merge outer flow - then check if first cas succeeded 634 region->set_req(1, then); 635 region->set_req(2, region2); 636 phi->set_req(1, cmpx); 637 phi->set_req(2, phi2); 638 639 gvn.transform(region2); 640 gvn.transform(phi2); 641 gvn.transform(region); 642 gvn.transform(phi); 643 644 kit->set_control(region); 645 kit->set_memory(in_mem, alias_idx); 646 kit->insert_mem_bar(Op_MemBarCPUOrder); 647 648 return phi; 649 } 650 651 Node* ZBarrierSetC2::load_barrier(GraphKit* kit, Node* val, Node* adr, bool weak, bool writeback, bool oop_reload_allowed) const { 652 PhaseGVN& gvn = kit->gvn(); 653 Node* barrier = new LoadBarrierNode(Compile::current(), kit->control(), kit->memory(TypeRawPtr::BOTTOM), val, adr, weak, writeback, oop_reload_allowed); 654 Node* transformed_barrier = gvn.transform(barrier); 655 656 if (transformed_barrier->is_LoadBarrier()) { 657 if (barrier == transformed_barrier) { 658 kit->set_control(gvn.transform(new ProjNode(barrier, LoadBarrierNode::Control))); 659 } 660 Node* result = gvn.transform(new ProjNode(transformed_barrier, LoadBarrierNode::Oop)); 661 assert(is_gc_barrier_node(result), "sanity"); 662 assert(step_over_gc_barrier(result) == val, "sanity"); 663 return result; 664 } else { 665 return val; 666 } 667 } 668 669 static bool barrier_needed(C2Access& access) { 670 return ZBarrierSet::barrier_needed(access.decorators(), access.type()); 671 } 672 673 Node* ZBarrierSetC2::load_at_resolved(C2Access& access, const Type* val_type) const { 674 Node* p = BarrierSetC2::load_at_resolved(access, val_type); 675 if (!barrier_needed(access)) { 676 return p; 677 } 678 679 bool weak = (access.decorators() & ON_WEAK_OOP_REF) != 0; 680 681 assert(access.is_parse_access(), "entry not supported at optimization time"); 682 C2ParseAccess& parse_access = static_cast<C2ParseAccess&>(access); 683 GraphKit* kit = parse_access.kit(); 684 PhaseGVN& gvn = kit->gvn(); 685 Node* adr = access.addr().node(); 686 Node* heap_base_oop = access.base(); 687 bool unsafe = (access.decorators() & C2_UNSAFE_ACCESS) != 0; 688 if (unsafe) { 689 if (!ZVerifyLoadBarriers) { 690 p = load_barrier(kit, p, adr); 691 } else { 692 if (!TypePtr::NULL_PTR->higher_equal(gvn.type(heap_base_oop))) { 693 p = load_barrier(kit, p, adr); 694 } else { 695 IdealKit ideal(kit); 696 IdealVariable res(ideal); 697 #define __ ideal. 698 __ declarations_done(); 699 __ set(res, p); 700 __ if_then(heap_base_oop, BoolTest::ne, kit->null(), PROB_UNLIKELY(0.999)); { 701 kit->sync_kit(ideal); 702 p = load_barrier(kit, p, adr); 703 __ set(res, p); 704 __ sync_kit(kit); 705 } __ end_if(); 706 kit->final_sync(ideal); 707 p = __ value(res); 708 #undef __ 709 } 710 } 711 return p; 712 } else { 713 return load_barrier(parse_access.kit(), p, access.addr().node(), weak, true, true); 714 } 715 } 716 717 Node* ZBarrierSetC2::atomic_cmpxchg_val_at_resolved(C2AtomicParseAccess& access, Node* expected_val, 718 Node* new_val, const Type* val_type) const { 719 Node* result = BarrierSetC2::atomic_cmpxchg_val_at_resolved(access, expected_val, new_val, val_type); 720 if (!barrier_needed(access)) { 721 return result; 722 } 723 724 access.set_needs_pinning(false); 725 return make_cmpx_loadbarrier(access); 726 } 727 728 Node* ZBarrierSetC2::atomic_cmpxchg_bool_at_resolved(C2AtomicParseAccess& access, Node* expected_val, 729 Node* new_val, const Type* value_type) const { 730 Node* result = BarrierSetC2::atomic_cmpxchg_bool_at_resolved(access, expected_val, new_val, value_type); 731 if (!barrier_needed(access)) { 732 return result; 733 } 734 735 Node* load_store = access.raw_access(); 736 bool weak_cas = (access.decorators() & C2_WEAK_CMPXCHG) != 0; 737 bool expected_is_null = (expected_val->get_ptr_type() == TypePtr::NULL_PTR); 738 739 if (!expected_is_null) { 740 if (weak_cas) { 741 access.set_needs_pinning(false); 742 load_store = make_cas_loadbarrier(access); 743 } else { 744 access.set_needs_pinning(false); 745 load_store = make_cas_loadbarrier(access); 746 } 747 } 748 749 return load_store; 750 } 751 752 Node* ZBarrierSetC2::atomic_xchg_at_resolved(C2AtomicParseAccess& access, Node* new_val, const Type* val_type) const { 753 Node* result = BarrierSetC2::atomic_xchg_at_resolved(access, new_val, val_type); 754 if (!barrier_needed(access)) { 755 return result; 756 } 757 758 Node* load_store = access.raw_access(); 759 Node* adr = access.addr().node(); 760 761 assert(access.is_parse_access(), "entry not supported at optimization time"); 762 C2ParseAccess& parse_access = static_cast<C2ParseAccess&>(access); 763 return load_barrier(parse_access.kit(), load_store, adr, false, false, false); 764 } 765 766 // == Macro Expansion == 767 768 void ZBarrierSetC2::expand_loadbarrier_node(PhaseMacroExpand* phase, LoadBarrierNode* barrier) const { 769 Node* in_ctrl = barrier->in(LoadBarrierNode::Control); 770 Node* in_mem = barrier->in(LoadBarrierNode::Memory); 771 Node* in_val = barrier->in(LoadBarrierNode::Oop); 772 Node* in_adr = barrier->in(LoadBarrierNode::Address); 773 774 Node* out_ctrl = barrier->proj_out(LoadBarrierNode::Control); 775 Node* out_res = barrier->proj_out(LoadBarrierNode::Oop); 776 777 PhaseIterGVN &igvn = phase->igvn(); 778 779 if (ZVerifyLoadBarriers) { 780 igvn.replace_node(out_res, in_val); 781 igvn.replace_node(out_ctrl, in_ctrl); 782 return; 783 } 784 785 if (barrier->can_be_eliminated()) { 786 // Clone and pin the load for this barrier below the dominating 787 // barrier: the load cannot be allowed to float above the 788 // dominating barrier 789 Node* load = in_val; 790 791 if (load->is_Load()) { 792 Node* new_load = load->clone(); 793 Node* addp = new_load->in(MemNode::Address); 794 assert(addp->is_AddP() || addp->is_Phi() || addp->is_Load(), "bad address"); 795 Node* cast = new CastPPNode(addp, igvn.type(addp), true); 796 Node* ctrl = NULL; 797 Node* similar = barrier->in(LoadBarrierNode::Similar); 798 if (similar->is_Phi()) { 799 // already expanded 800 ctrl = similar->in(0); 801 } else { 802 assert(similar->is_Proj() && similar->in(0)->is_LoadBarrier(), "unexpected graph shape"); 803 ctrl = similar->in(0)->as_LoadBarrier()->proj_out(LoadBarrierNode::Control); 804 } 805 assert(ctrl != NULL, "bad control"); 806 cast->set_req(0, ctrl); 807 igvn.transform(cast); 808 new_load->set_req(MemNode::Address, cast); 809 igvn.transform(new_load); 810 811 igvn.replace_node(out_res, new_load); 812 igvn.replace_node(out_ctrl, in_ctrl); 813 return; 814 } 815 // cannot eliminate 816 } 817 818 // There are two cases that require the basic loadbarrier 819 // 1) When the writeback of a healed oop must be avoided (swap) 820 // 2) When we must guarantee that no reload of is done (swap, cas, cmpx) 821 if (!barrier->is_writeback()) { 822 assert(!barrier->oop_reload_allowed(), "writeback barriers should be marked as requires oop"); 823 } 824 825 if (!barrier->oop_reload_allowed()) { 826 expand_loadbarrier_basic(phase, barrier); 827 } else { 828 expand_loadbarrier_optimized(phase, barrier); 829 } 830 } 831 832 // Basic loadbarrier using conventional argument passing 833 void ZBarrierSetC2::expand_loadbarrier_basic(PhaseMacroExpand* phase, LoadBarrierNode *barrier) const { 834 PhaseIterGVN &igvn = phase->igvn(); 835 836 Node* in_ctrl = barrier->in(LoadBarrierNode::Control); 837 Node* in_mem = barrier->in(LoadBarrierNode::Memory); 838 Node* in_val = barrier->in(LoadBarrierNode::Oop); 839 Node* in_adr = barrier->in(LoadBarrierNode::Address); 840 841 Node* out_ctrl = barrier->proj_out(LoadBarrierNode::Control); 842 Node* out_res = barrier->proj_out(LoadBarrierNode::Oop); 843 844 float unlikely = PROB_UNLIKELY(0.999); 845 const Type* in_val_maybe_null_t = igvn.type(in_val); 846 847 Node* jthread = igvn.transform(new ThreadLocalNode()); 848 Node* adr = phase->basic_plus_adr(jthread, in_bytes(ZThreadLocalData::address_bad_mask_offset())); 849 Node* bad_mask = igvn.transform(LoadNode::make(igvn, in_ctrl, in_mem, adr, TypeRawPtr::BOTTOM, TypeX_X, TypeX_X->basic_type(), MemNode::unordered)); 850 Node* cast = igvn.transform(new CastP2XNode(in_ctrl, in_val)); 851 Node* obj_masked = igvn.transform(new AndXNode(cast, bad_mask)); 852 Node* cmp = igvn.transform(new CmpXNode(obj_masked, igvn.zerocon(TypeX_X->basic_type()))); 853 Node *bol = igvn.transform(new BoolNode(cmp, BoolTest::ne))->as_Bool(); 854 IfNode* iff = igvn.transform(new IfNode(in_ctrl, bol, unlikely, COUNT_UNKNOWN))->as_If(); 855 Node* then = igvn.transform(new IfTrueNode(iff)); 856 Node* elsen = igvn.transform(new IfFalseNode(iff)); 857 858 Node* result_region; 859 Node* result_val; 860 861 result_region = new RegionNode(3); 862 result_val = new PhiNode(result_region, TypeInstPtr::BOTTOM); 863 864 result_region->set_req(1, elsen); 865 Node* res = igvn.transform(new CastPPNode(in_val, in_val_maybe_null_t)); 866 res->init_req(0, elsen); 867 result_val->set_req(1, res); 868 869 const TypeFunc *tf = load_barrier_Type(); 870 Node* call; 871 if (barrier->is_weak()) { 872 call = new CallLeafNode(tf, 873 ZBarrierSetRuntime::load_barrier_on_weak_oop_field_preloaded_addr(), 874 "ZBarrierSetRuntime::load_barrier_on_weak_oop_field_preloaded", 875 TypeRawPtr::BOTTOM); 876 } else { 877 call = new CallLeafNode(tf, 878 ZBarrierSetRuntime::load_barrier_on_oop_field_preloaded_addr(), 879 "ZBarrierSetRuntime::load_barrier_on_oop_field_preloaded", 880 TypeRawPtr::BOTTOM); 881 } 882 883 call->init_req(TypeFunc::Control, then); 884 call->init_req(TypeFunc::I_O , phase->top()); 885 call->init_req(TypeFunc::Memory , in_mem); 886 call->init_req(TypeFunc::FramePtr, phase->top()); 887 call->init_req(TypeFunc::ReturnAdr, phase->top()); 888 call->init_req(TypeFunc::Parms+0, in_val); 889 if (barrier->is_writeback()) { 890 call->init_req(TypeFunc::Parms+1, in_adr); 891 } else { 892 // When slow path is called with a null address, the healed oop will not be written back 893 call->init_req(TypeFunc::Parms+1, igvn.zerocon(T_OBJECT)); 894 } 895 call = igvn.transform(call); 896 897 Node* ctrl = igvn.transform(new ProjNode(call, TypeFunc::Control)); 898 res = igvn.transform(new ProjNode(call, TypeFunc::Parms)); 899 res = igvn.transform(new CheckCastPPNode(ctrl, res, in_val_maybe_null_t)); 900 901 result_region->set_req(2, ctrl); 902 result_val->set_req(2, res); 903 904 result_region = igvn.transform(result_region); 905 result_val = igvn.transform(result_val); 906 907 if (out_ctrl != NULL) { // Added if cond 908 igvn.replace_node(out_ctrl, result_region); 909 } 910 igvn.replace_node(out_res, result_val); 911 } 912 913 // Optimized, low spill, loadbarrier variant using stub specialized on register used 914 void ZBarrierSetC2::expand_loadbarrier_optimized(PhaseMacroExpand* phase, LoadBarrierNode *barrier) const { 915 PhaseIterGVN &igvn = phase->igvn(); 916 #ifdef PRINT_NODE_TRAVERSALS 917 Node* preceding_barrier_node = barrier->in(LoadBarrierNode::Oop); 918 #endif 919 920 Node* in_ctrl = barrier->in(LoadBarrierNode::Control); 921 Node* in_mem = barrier->in(LoadBarrierNode::Memory); 922 Node* in_val = barrier->in(LoadBarrierNode::Oop); 923 Node* in_adr = barrier->in(LoadBarrierNode::Address); 924 925 Node* out_ctrl = barrier->proj_out(LoadBarrierNode::Control); 926 Node* out_res = barrier->proj_out(LoadBarrierNode::Oop); 927 928 assert(barrier->in(LoadBarrierNode::Oop) != NULL, "oop to loadbarrier node cannot be null"); 929 930 #ifdef PRINT_NODE_TRAVERSALS 931 tty->print("\n\n\nBefore barrier optimization:\n"); 932 traverse(barrier, out_ctrl, out_res, -1); 933 934 tty->print("\nBefore barrier optimization: preceding_barrier_node\n"); 935 traverse(preceding_barrier_node, out_ctrl, out_res, -1); 936 #endif 937 938 float unlikely = PROB_UNLIKELY(0.999); 939 940 Node* jthread = igvn.transform(new ThreadLocalNode()); 941 Node* adr = phase->basic_plus_adr(jthread, in_bytes(ZThreadLocalData::address_bad_mask_offset())); 942 Node* bad_mask = igvn.transform(LoadNode::make(igvn, in_ctrl, in_mem, adr, 943 TypeRawPtr::BOTTOM, TypeX_X, TypeX_X->basic_type(), 944 MemNode::unordered)); 945 Node* cast = igvn.transform(new CastP2XNode(in_ctrl, in_val)); 946 Node* obj_masked = igvn.transform(new AndXNode(cast, bad_mask)); 947 Node* cmp = igvn.transform(new CmpXNode(obj_masked, igvn.zerocon(TypeX_X->basic_type()))); 948 Node *bol = igvn.transform(new BoolNode(cmp, BoolTest::ne))->as_Bool(); 949 IfNode* iff = igvn.transform(new IfNode(in_ctrl, bol, unlikely, COUNT_UNKNOWN))->as_If(); 950 Node* then = igvn.transform(new IfTrueNode(iff)); 951 Node* elsen = igvn.transform(new IfFalseNode(iff)); 952 953 Node* slow_path_surrogate; 954 if (!barrier->is_weak()) { 955 slow_path_surrogate = igvn.transform(new LoadBarrierSlowRegNode(then, in_mem, in_adr, in_val->adr_type(), 956 (const TypePtr*) in_val->bottom_type(), MemNode::unordered)); 957 } else { 958 slow_path_surrogate = igvn.transform(new LoadBarrierWeakSlowRegNode(then, in_mem, in_adr, in_val->adr_type(), 959 (const TypePtr*) in_val->bottom_type(), MemNode::unordered)); 960 } 961 962 Node *new_loadp; 963 new_loadp = slow_path_surrogate; 964 // Create the final region/phi pair to converge cntl/data paths to downstream code 965 Node* result_region = igvn.transform(new RegionNode(3)); 966 result_region->set_req(1, then); 967 result_region->set_req(2, elsen); 968 969 Node* result_phi = igvn.transform(new PhiNode(result_region, TypeInstPtr::BOTTOM)); 970 result_phi->set_req(1, new_loadp); 971 result_phi->set_req(2, barrier->in(LoadBarrierNode::Oop)); 972 973 // Finally, connect the original outputs to the barrier region and phi to complete the expansion/substitution 974 // igvn.replace_node(out_ctrl, result_region); 975 if (out_ctrl != NULL) { // added if cond 976 igvn.replace_node(out_ctrl, result_region); 977 } 978 igvn.replace_node(out_res, result_phi); 979 980 assert(barrier->outcnt() == 0,"LoadBarrier macro node has non-null outputs after expansion!"); 981 982 #ifdef PRINT_NODE_TRAVERSALS 983 tty->print("\nAfter barrier optimization: old out_ctrl\n"); 984 traverse(out_ctrl, out_ctrl, out_res, -1); 985 tty->print("\nAfter barrier optimization: old out_res\n"); 986 traverse(out_res, out_ctrl, out_res, -1); 987 tty->print("\nAfter barrier optimization: old barrier\n"); 988 traverse(barrier, out_ctrl, out_res, -1); 989 tty->print("\nAfter barrier optimization: preceding_barrier_node\n"); 990 traverse(preceding_barrier_node, result_region, result_phi, -1); 991 #endif 992 993 assert(is_gc_barrier_node(result_phi), "sanity"); 994 assert(step_over_gc_barrier(result_phi) == in_val, "sanity"); 995 996 return; 997 } 998 999 bool ZBarrierSetC2::expand_barriers(Compile* C, PhaseIterGVN& igvn) const { 1000 PhaseMacroExpand macro(igvn); 1001 ZBarrierSetC2State* s = state(); 1002 if (s->load_barrier_count() > 0) { 1003 #ifdef ASSERT 1004 verify_gc_barriers(false); 1005 #endif 1006 igvn.set_delay_transform(true); 1007 int skipped = 0; 1008 while (s->load_barrier_count() > skipped) { 1009 int load_barrier_count = s->load_barrier_count(); 1010 LoadBarrierNode * n = s->load_barrier_node(load_barrier_count-1-skipped); 1011 if (igvn.type(n) == Type::TOP || (n->in(0) != NULL && n->in(0)->is_top())) { 1012 // Node is unreachable, so don't try to expand it 1013 s->remove_load_barrier_node(n); 1014 continue; 1015 } 1016 if (!n->can_be_eliminated()) { 1017 skipped++; 1018 continue; 1019 } 1020 expand_loadbarrier_node(¯o, n); 1021 assert(s->load_barrier_count() < load_barrier_count, "must have deleted a node from load barrier list"); 1022 if (C->failing()) return true; 1023 } 1024 while (s->load_barrier_count() > 0) { 1025 int load_barrier_count = s->load_barrier_count(); 1026 LoadBarrierNode* n = s->load_barrier_node(load_barrier_count - 1); 1027 assert(!(igvn.type(n) == Type::TOP || (n->in(0) != NULL && n->in(0)->is_top())), "should have been processed already"); 1028 assert(!n->can_be_eliminated(), "should have been processed already"); 1029 expand_loadbarrier_node(¯o, n); 1030 assert(s->load_barrier_count() < load_barrier_count, "must have deleted a node from load barrier list"); 1031 if (C->failing()) return true; 1032 } 1033 igvn.set_delay_transform(false); 1034 igvn.optimize(); 1035 if (C->failing()) return true; 1036 } 1037 return false; 1038 } 1039 1040 // == Loop optimization == 1041 1042 static bool replace_with_dominating_barrier(PhaseIdealLoop* phase, LoadBarrierNode* lb, bool last_round) { 1043 PhaseIterGVN &igvn = phase->igvn(); 1044 Compile* C = Compile::current(); 1045 1046 LoadBarrierNode* lb2 = lb->has_dominating_barrier(phase, false, last_round); 1047 if (lb2 != NULL) { 1048 if (lb->in(LoadBarrierNode::Oop) != lb2->in(LoadBarrierNode::Oop)) { 1049 assert(lb->in(LoadBarrierNode::Address) == lb2->in(LoadBarrierNode::Address), ""); 1050 igvn.replace_input_of(lb, LoadBarrierNode::Similar, lb2->proj_out(LoadBarrierNode::Oop)); 1051 C->set_major_progress(); 1052 } else { 1053 // That transformation may cause the Similar edge on dominated load barriers to be invalid 1054 lb->fix_similar_in_uses(&igvn); 1055 1056 Node* val = lb->proj_out(LoadBarrierNode::Oop); 1057 assert(lb2->has_true_uses(), ""); 1058 assert(lb2->in(LoadBarrierNode::Oop) == lb->in(LoadBarrierNode::Oop), ""); 1059 1060 phase->lazy_update(lb, lb->in(LoadBarrierNode::Control)); 1061 phase->lazy_replace(lb->proj_out(LoadBarrierNode::Control), lb->in(LoadBarrierNode::Control)); 1062 igvn.replace_node(val, lb2->proj_out(LoadBarrierNode::Oop)); 1063 1064 return true; 1065 } 1066 } 1067 return false; 1068 } 1069 1070 static Node* find_dominating_memory(PhaseIdealLoop* phase, Node* mem, Node* dom, int i) { 1071 assert(dom->is_Region() || i == -1, ""); 1072 Node* m = mem; 1073 while(phase->is_dominator(dom, phase->has_ctrl(m) ? phase->get_ctrl(m) : m->in(0))) { 1074 if (m->is_Mem()) { 1075 assert(m->as_Mem()->adr_type() == TypeRawPtr::BOTTOM, ""); 1076 m = m->in(MemNode::Memory); 1077 } else if (m->is_MergeMem()) { 1078 m = m->as_MergeMem()->memory_at(Compile::AliasIdxRaw); 1079 } else if (m->is_Phi()) { 1080 if (m->in(0) == dom && i != -1) { 1081 m = m->in(i); 1082 break; 1083 } else { 1084 m = m->in(LoopNode::EntryControl); 1085 } 1086 } else if (m->is_Proj()) { 1087 m = m->in(0); 1088 } else if (m->is_SafePoint() || m->is_MemBar()) { 1089 m = m->in(TypeFunc::Memory); 1090 } else { 1091 #ifdef ASSERT 1092 m->dump(); 1093 #endif 1094 ShouldNotReachHere(); 1095 } 1096 } 1097 return m; 1098 } 1099 1100 static LoadBarrierNode* clone_load_barrier(PhaseIdealLoop* phase, LoadBarrierNode* lb, Node* ctl, Node* mem, Node* oop_in) { 1101 PhaseIterGVN &igvn = phase->igvn(); 1102 Compile* C = Compile::current(); 1103 Node* the_clone = lb->clone(); 1104 the_clone->set_req(LoadBarrierNode::Control, ctl); 1105 the_clone->set_req(LoadBarrierNode::Memory, mem); 1106 if (oop_in != NULL) { 1107 the_clone->set_req(LoadBarrierNode::Oop, oop_in); 1108 } 1109 1110 LoadBarrierNode* new_lb = the_clone->as_LoadBarrier(); 1111 igvn.register_new_node_with_optimizer(new_lb); 1112 IdealLoopTree *loop = phase->get_loop(new_lb->in(0)); 1113 phase->set_ctrl(new_lb, new_lb->in(0)); 1114 phase->set_loop(new_lb, loop); 1115 phase->set_idom(new_lb, new_lb->in(0), phase->dom_depth(new_lb->in(0))+1); 1116 if (!loop->_child) { 1117 loop->_body.push(new_lb); 1118 } 1119 1120 Node* proj_ctl = new ProjNode(new_lb, LoadBarrierNode::Control); 1121 igvn.register_new_node_with_optimizer(proj_ctl); 1122 phase->set_ctrl(proj_ctl, proj_ctl->in(0)); 1123 phase->set_loop(proj_ctl, loop); 1124 phase->set_idom(proj_ctl, new_lb, phase->dom_depth(new_lb)+1); 1125 if (!loop->_child) { 1126 loop->_body.push(proj_ctl); 1127 } 1128 1129 Node* proj_oop = new ProjNode(new_lb, LoadBarrierNode::Oop); 1130 phase->register_new_node(proj_oop, new_lb); 1131 1132 if (!new_lb->in(LoadBarrierNode::Similar)->is_top()) { 1133 LoadBarrierNode* similar = new_lb->in(LoadBarrierNode::Similar)->in(0)->as_LoadBarrier(); 1134 if (!phase->is_dominator(similar, ctl)) { 1135 igvn.replace_input_of(new_lb, LoadBarrierNode::Similar, C->top()); 1136 } 1137 } 1138 1139 return new_lb; 1140 } 1141 1142 static void replace_barrier(PhaseIdealLoop* phase, LoadBarrierNode* lb, Node* new_val) { 1143 PhaseIterGVN &igvn = phase->igvn(); 1144 Node* val = lb->proj_out(LoadBarrierNode::Oop); 1145 igvn.replace_node(val, new_val); 1146 phase->lazy_update(lb, lb->in(LoadBarrierNode::Control)); 1147 phase->lazy_replace(lb->proj_out(LoadBarrierNode::Control), lb->in(LoadBarrierNode::Control)); 1148 } 1149 1150 static bool split_barrier_thru_phi(PhaseIdealLoop* phase, LoadBarrierNode* lb) { 1151 PhaseIterGVN &igvn = phase->igvn(); 1152 Compile* C = Compile::current(); 1153 1154 if (lb->in(LoadBarrierNode::Oop)->is_Phi()) { 1155 Node* oop_phi = lb->in(LoadBarrierNode::Oop); 1156 1157 if (oop_phi->in(2) == oop_phi) { 1158 // Ignore phis with only one input 1159 return false; 1160 } 1161 1162 if (phase->is_dominator(phase->get_ctrl(lb->in(LoadBarrierNode::Address)), 1163 oop_phi->in(0)) && phase->get_ctrl(lb->in(LoadBarrierNode::Address)) != oop_phi->in(0)) { 1164 // That transformation may cause the Similar edge on dominated load barriers to be invalid 1165 lb->fix_similar_in_uses(&igvn); 1166 1167 RegionNode* region = oop_phi->in(0)->as_Region(); 1168 1169 int backedge = LoopNode::LoopBackControl; 1170 if (region->is_Loop() && region->in(backedge)->is_Proj() && region->in(backedge)->in(0)->is_If()) { 1171 Node* c = region->in(backedge)->in(0)->in(0); 1172 assert(c->unique_ctrl_out() == region->in(backedge)->in(0), ""); 1173 Node* oop = lb->in(LoadBarrierNode::Oop)->in(backedge); 1174 Node* oop_c = phase->has_ctrl(oop) ? phase->get_ctrl(oop) : oop; 1175 if (!phase->is_dominator(oop_c, c)) { 1176 return false; 1177 } 1178 } 1179 1180 // If the node on the backedge above the phi is the node itself - we have a self loop. 1181 // Don't clone - this will be folded later. 1182 if (oop_phi->in(LoopNode::LoopBackControl) == lb->proj_out(LoadBarrierNode::Oop)) { 1183 return false; 1184 } 1185 1186 bool is_strip_mined = region->is_CountedLoop() && region->as_CountedLoop()->is_strip_mined(); 1187 Node *phi = oop_phi->clone(); 1188 1189 for (uint i = 1; i < region->req(); i++) { 1190 Node* ctrl = region->in(i); 1191 if (ctrl != C->top()) { 1192 assert(!phase->is_dominator(ctrl, region) || region->is_Loop(), ""); 1193 1194 Node* mem = lb->in(LoadBarrierNode::Memory); 1195 Node* m = find_dominating_memory(phase, mem, region, i); 1196 1197 if (region->is_Loop() && i == LoopNode::LoopBackControl && ctrl->is_Proj() && ctrl->in(0)->is_If()) { 1198 ctrl = ctrl->in(0)->in(0); 1199 } else if (region->is_Loop() && is_strip_mined) { 1200 // If this is a strip mined loop, control must move above OuterStripMinedLoop 1201 assert(i == LoopNode::EntryControl, "check"); 1202 assert(ctrl->is_OuterStripMinedLoop(), "sanity"); 1203 ctrl = ctrl->as_OuterStripMinedLoop()->in(LoopNode::EntryControl); 1204 } 1205 1206 LoadBarrierNode* new_lb = clone_load_barrier(phase, lb, ctrl, m, lb->in(LoadBarrierNode::Oop)->in(i)); 1207 Node* out_ctrl = new_lb->proj_out(LoadBarrierNode::Control); 1208 1209 if (is_strip_mined && (i == LoopNode::EntryControl)) { 1210 assert(region->in(i)->is_OuterStripMinedLoop(), ""); 1211 igvn.replace_input_of(region->in(i), i, out_ctrl); 1212 phase->set_idom(region->in(i), out_ctrl, phase->dom_depth(out_ctrl)); 1213 } else if (ctrl == region->in(i)) { 1214 igvn.replace_input_of(region, i, out_ctrl); 1215 // Only update the idom if is the loop entry we are updating 1216 // - A loop backedge doesn't change the idom 1217 if (region->is_Loop() && i == LoopNode::EntryControl) { 1218 phase->set_idom(region, out_ctrl, phase->dom_depth(out_ctrl)); 1219 } 1220 } else { 1221 Node* iff = region->in(i)->in(0); 1222 igvn.replace_input_of(iff, 0, out_ctrl); 1223 phase->set_idom(iff, out_ctrl, phase->dom_depth(out_ctrl)+1); 1224 } 1225 phi->set_req(i, new_lb->proj_out(LoadBarrierNode::Oop)); 1226 } 1227 } 1228 phase->register_new_node(phi, region); 1229 replace_barrier(phase, lb, phi); 1230 1231 if (region->is_Loop()) { 1232 // Load barrier moved to the back edge of the Loop may now 1233 // have a safepoint on the path to the barrier on the Similar 1234 // edge 1235 igvn.replace_input_of(phi->in(LoopNode::LoopBackControl)->in(0), LoadBarrierNode::Similar, C->top()); 1236 Node* head = region->in(LoopNode::EntryControl); 1237 phase->set_idom(region, head, phase->dom_depth(head)+1); 1238 phase->recompute_dom_depth(); 1239 if (head->is_CountedLoop() && head->as_CountedLoop()->is_main_loop()) { 1240 head->as_CountedLoop()->set_normal_loop(); 1241 } 1242 } 1243 1244 return true; 1245 } 1246 } 1247 1248 return false; 1249 } 1250 1251 static bool move_out_of_loop(PhaseIdealLoop* phase, LoadBarrierNode* lb) { 1252 PhaseIterGVN &igvn = phase->igvn(); 1253 IdealLoopTree *lb_loop = phase->get_loop(lb->in(0)); 1254 if (lb_loop != phase->ltree_root() && !lb_loop->_irreducible) { 1255 Node* oop_ctrl = phase->get_ctrl(lb->in(LoadBarrierNode::Oop)); 1256 IdealLoopTree *oop_loop = phase->get_loop(oop_ctrl); 1257 IdealLoopTree* adr_loop = phase->get_loop(phase->get_ctrl(lb->in(LoadBarrierNode::Address))); 1258 if (!lb_loop->is_member(oop_loop) && !lb_loop->is_member(adr_loop)) { 1259 // That transformation may cause the Similar edge on dominated load barriers to be invalid 1260 lb->fix_similar_in_uses(&igvn); 1261 1262 Node* head = lb_loop->_head; 1263 assert(head->is_Loop(), ""); 1264 1265 if (phase->is_dominator(head, oop_ctrl)) { 1266 assert(oop_ctrl->Opcode() == Op_CProj && oop_ctrl->in(0)->Opcode() == Op_NeverBranch, ""); 1267 assert(lb_loop->is_member(phase->get_loop(oop_ctrl->in(0)->in(0))), ""); 1268 return false; 1269 } 1270 1271 if (head->is_CountedLoop()) { 1272 CountedLoopNode* cloop = head->as_CountedLoop(); 1273 if (cloop->is_main_loop()) { 1274 cloop->set_normal_loop(); 1275 } 1276 // When we are moving barrier out of a counted loop, 1277 // make sure we move it all the way out of the strip mined outer loop. 1278 if (cloop->is_strip_mined()) { 1279 head = cloop->outer_loop(); 1280 } 1281 } 1282 1283 Node* mem = lb->in(LoadBarrierNode::Memory); 1284 Node* m = find_dominating_memory(phase, mem, head, -1); 1285 1286 LoadBarrierNode* new_lb = clone_load_barrier(phase, lb, head->in(LoopNode::EntryControl), m, NULL); 1287 1288 assert(phase->idom(head) == head->in(LoopNode::EntryControl), ""); 1289 Node* proj_ctl = new_lb->proj_out(LoadBarrierNode::Control); 1290 igvn.replace_input_of(head, LoopNode::EntryControl, proj_ctl); 1291 phase->set_idom(head, proj_ctl, phase->dom_depth(proj_ctl) + 1); 1292 1293 replace_barrier(phase, lb, new_lb->proj_out(LoadBarrierNode::Oop)); 1294 1295 phase->recompute_dom_depth(); 1296 1297 return true; 1298 } 1299 } 1300 1301 return false; 1302 } 1303 1304 static bool common_barriers(PhaseIdealLoop* phase, LoadBarrierNode* lb) { 1305 PhaseIterGVN &igvn = phase->igvn(); 1306 Node* in_val = lb->in(LoadBarrierNode::Oop); 1307 for (DUIterator_Fast imax, i = in_val->fast_outs(imax); i < imax; i++) { 1308 Node* u = in_val->fast_out(i); 1309 if (u != lb && u->is_LoadBarrier() && u->as_LoadBarrier()->has_true_uses()) { 1310 Node* this_ctrl = lb->in(LoadBarrierNode::Control); 1311 Node* other_ctrl = u->in(LoadBarrierNode::Control); 1312 1313 Node* lca = phase->dom_lca(this_ctrl, other_ctrl); 1314 bool ok = true; 1315 1316 Node* proj1 = NULL; 1317 Node* proj2 = NULL; 1318 1319 while (this_ctrl != lca && ok) { 1320 if (this_ctrl->in(0) != NULL && 1321 this_ctrl->in(0)->is_MultiBranch()) { 1322 if (this_ctrl->in(0)->in(0) == lca) { 1323 assert(proj1 == NULL, ""); 1324 assert(this_ctrl->is_Proj(), ""); 1325 proj1 = this_ctrl; 1326 } else if (!(this_ctrl->in(0)->is_If() && this_ctrl->as_Proj()->is_uncommon_trap_if_pattern(Deoptimization::Reason_none))) { 1327 ok = false; 1328 } 1329 } 1330 this_ctrl = phase->idom(this_ctrl); 1331 } 1332 while (other_ctrl != lca && ok) { 1333 if (other_ctrl->in(0) != NULL && 1334 other_ctrl->in(0)->is_MultiBranch()) { 1335 if (other_ctrl->in(0)->in(0) == lca) { 1336 assert(other_ctrl->is_Proj(), ""); 1337 assert(proj2 == NULL, ""); 1338 proj2 = other_ctrl; 1339 } else if (!(other_ctrl->in(0)->is_If() && other_ctrl->as_Proj()->is_uncommon_trap_if_pattern(Deoptimization::Reason_none))) { 1340 ok = false; 1341 } 1342 } 1343 other_ctrl = phase->idom(other_ctrl); 1344 } 1345 assert(proj1 == NULL || proj2 == NULL || proj1->in(0) == proj2->in(0), ""); 1346 if (ok && proj1 && proj2 && proj1 != proj2 && proj1->in(0)->is_If()) { 1347 // That transformation may cause the Similar edge on dominated load barriers to be invalid 1348 lb->fix_similar_in_uses(&igvn); 1349 u->as_LoadBarrier()->fix_similar_in_uses(&igvn); 1350 1351 Node* split = lca->unique_ctrl_out(); 1352 assert(split->in(0) == lca, ""); 1353 1354 Node* mem = lb->in(LoadBarrierNode::Memory); 1355 Node* m = find_dominating_memory(phase, mem, split, -1); 1356 LoadBarrierNode* new_lb = clone_load_barrier(phase, lb, lca, m, NULL); 1357 1358 Node* proj_ctl = new_lb->proj_out(LoadBarrierNode::Control); 1359 igvn.replace_input_of(split, 0, new_lb->proj_out(LoadBarrierNode::Control)); 1360 phase->set_idom(split, proj_ctl, phase->dom_depth(proj_ctl)+1); 1361 1362 Node* proj_oop = new_lb->proj_out(LoadBarrierNode::Oop); 1363 replace_barrier(phase, lb, proj_oop); 1364 replace_barrier(phase, u->as_LoadBarrier(), proj_oop); 1365 1366 phase->recompute_dom_depth(); 1367 1368 return true; 1369 } 1370 } 1371 } 1372 1373 return false; 1374 } 1375 1376 static void optimize_load_barrier(PhaseIdealLoop* phase, LoadBarrierNode* lb, bool last_round) { 1377 Compile* C = Compile::current(); 1378 1379 if (!C->directive()->ZOptimizeLoadBarriersOption) { 1380 return; 1381 } 1382 1383 if (lb->has_true_uses()) { 1384 if (replace_with_dominating_barrier(phase, lb, last_round)) { 1385 return; 1386 } 1387 1388 if (split_barrier_thru_phi(phase, lb)) { 1389 return; 1390 } 1391 1392 if (move_out_of_loop(phase, lb)) { 1393 return; 1394 } 1395 1396 if (common_barriers(phase, lb)) { 1397 return; 1398 } 1399 } 1400 } 1401 1402 void ZBarrierSetC2::loop_optimize_gc_barrier(PhaseIdealLoop* phase, Node* node, bool last_round) { 1403 if (node->is_LoadBarrier()) { 1404 optimize_load_barrier(phase, node->as_LoadBarrier(), last_round); 1405 } 1406 } 1407 1408 Node* ZBarrierSetC2::step_over_gc_barrier(Node* c) const { 1409 Node* node = c; 1410 1411 // 1. This step follows potential oop projections of a load barrier before expansion 1412 if (node->is_Proj()) { 1413 node = node->in(0); 1414 } 1415 1416 // 2. This step checks for unexpanded load barriers 1417 if (node->is_LoadBarrier()) { 1418 return node->in(LoadBarrierNode::Oop); 1419 } 1420 1421 // 3. This step checks for the phi corresponding to an optimized load barrier expansion 1422 if (node->is_Phi()) { 1423 PhiNode* phi = node->as_Phi(); 1424 Node* n = phi->in(1); 1425 if (n != NULL && (n->is_LoadBarrierSlowReg() || n->is_LoadBarrierWeakSlowReg())) { 1426 assert(c == node, "projections from step 1 should only be seen before macro expansion"); 1427 return phi->in(2); 1428 } 1429 } 1430 1431 return c; 1432 } 1433 1434 bool ZBarrierSetC2::array_copy_requires_gc_barriers(bool tightly_coupled_alloc, BasicType type, bool is_clone, ArrayCopyPhase phase) const { 1435 return type == T_OBJECT || type == T_ARRAY; 1436 } 1437 1438 bool ZBarrierSetC2::final_graph_reshaping(Compile* compile, Node* n, uint opcode) const { 1439 bool handled; 1440 switch (opcode) { 1441 case Op_LoadBarrierSlowReg: 1442 case Op_LoadBarrierWeakSlowReg: 1443 #ifdef ASSERT 1444 if (VerifyOptoOopOffsets) { 1445 MemNode* mem = n->as_Mem(); 1446 // Check to see if address types have grounded out somehow. 1447 const TypeInstPtr* tp = mem->in(MemNode::Address)->bottom_type()->isa_instptr(); 1448 ciInstanceKlass* k = tp->klass()->as_instance_klass(); 1449 bool oop_offset_is_sane = k->contains_field_offset(tp->offset()); 1450 assert(!tp || oop_offset_is_sane, ""); 1451 } 1452 #endif 1453 handled = true; 1454 break; 1455 default: 1456 handled = false; 1457 } 1458 return handled; 1459 } 1460 1461 bool ZBarrierSetC2::matcher_find_shared_visit(Matcher* matcher, Matcher::MStack& mstack, Node* n, uint opcode, bool& mem_op, int& mem_addr_idx) const { 1462 if (opcode == Op_CallLeaf && 1463 (n->as_Call()->entry_point() == ZBarrierSetRuntime::load_barrier_on_oop_field_preloaded_addr() || 1464 n->as_Call()->entry_point() == ZBarrierSetRuntime::load_barrier_on_weak_oop_field_preloaded_addr())) { 1465 mem_op = true; 1466 mem_addr_idx = TypeFunc::Parms + 1; 1467 return true; 1468 } 1469 return false; 1470 } 1471 1472 // == Verification == 1473 1474 #ifdef ASSERT 1475 1476 static bool look_for_barrier(Node* n, bool post_parse, VectorSet& visited) { 1477 if (visited.test_set(n->_idx)) { 1478 return true; 1479 } 1480 1481 for (DUIterator_Fast imax, i = n->fast_outs(imax); i < imax; i++) { 1482 Node* u = n->fast_out(i); 1483 if (u->is_LoadBarrier()) { 1484 } else if ((u->is_Phi() || u->is_CMove()) && !post_parse) { 1485 if (!look_for_barrier(u, post_parse, visited)) { 1486 return false; 1487 } 1488 } else if (u->Opcode() == Op_EncodeP || u->Opcode() == Op_DecodeN) { 1489 if (!look_for_barrier(u, post_parse, visited)) { 1490 return false; 1491 } 1492 } else if (u->Opcode() != Op_SCMemProj) { 1493 tty->print("bad use"); u->dump(); 1494 return false; 1495 } 1496 } 1497 1498 return true; 1499 } 1500 1501 void ZBarrierSetC2::verify_gc_barriers(Compile* compile, CompilePhase phase) const { 1502 if (phase == BarrierSetC2::BeforeCodeGen) return; 1503 bool post_parse = phase == BarrierSetC2::BeforeOptimize; 1504 verify_gc_barriers(post_parse); 1505 } 1506 1507 void ZBarrierSetC2::verify_gc_barriers(bool post_parse) const { 1508 ZBarrierSetC2State* s = state(); 1509 Compile* C = Compile::current(); 1510 ResourceMark rm; 1511 VectorSet visited(Thread::current()->resource_area()); 1512 for (int i = 0; i < s->load_barrier_count(); i++) { 1513 LoadBarrierNode* n = s->load_barrier_node(i); 1514 1515 // The dominating barrier on the same address if it exists and 1516 // this barrier must not be applied on the value from the same 1517 // load otherwise the value is not reloaded before it's used the 1518 // second time. 1519 assert(n->in(LoadBarrierNode::Similar)->is_top() || 1520 (n->in(LoadBarrierNode::Similar)->in(0)->is_LoadBarrier() && 1521 n->in(LoadBarrierNode::Similar)->in(0)->in(LoadBarrierNode::Address) == n->in(LoadBarrierNode::Address) && 1522 n->in(LoadBarrierNode::Similar)->in(0)->in(LoadBarrierNode::Oop) != n->in(LoadBarrierNode::Oop)), 1523 "broken similar edge"); 1524 1525 assert(post_parse || n->as_LoadBarrier()->has_true_uses(), 1526 "found unneeded load barrier"); 1527 1528 // Several load barrier nodes chained through their Similar edge 1529 // break the code that remove the barriers in final graph reshape. 1530 assert(n->in(LoadBarrierNode::Similar)->is_top() || 1531 (n->in(LoadBarrierNode::Similar)->in(0)->is_LoadBarrier() && 1532 n->in(LoadBarrierNode::Similar)->in(0)->in(LoadBarrierNode::Similar)->is_top()), 1533 "chain of Similar load barriers"); 1534 1535 if (!n->in(LoadBarrierNode::Similar)->is_top()) { 1536 ResourceMark rm; 1537 Unique_Node_List wq; 1538 Node* other = n->in(LoadBarrierNode::Similar)->in(0); 1539 wq.push(n); 1540 bool ok = true; 1541 bool dom_found = false; 1542 for (uint next = 0; next < wq.size(); ++next) { 1543 Node *n = wq.at(next); 1544 assert(n->is_CFG(), ""); 1545 assert(!n->is_SafePoint(), ""); 1546 1547 if (n == other) { 1548 continue; 1549 } 1550 1551 if (n->is_Region()) { 1552 for (uint i = 1; i < n->req(); i++) { 1553 Node* m = n->in(i); 1554 if (m != NULL) { 1555 wq.push(m); 1556 } 1557 } 1558 } else { 1559 Node* m = n->in(0); 1560 if (m != NULL) { 1561 wq.push(m); 1562 } 1563 } 1564 } 1565 } 1566 1567 if (ZVerifyLoadBarriers) { 1568 if ((n->is_Load() || n->is_LoadStore()) && n->bottom_type()->make_oopptr() != NULL) { 1569 visited.Clear(); 1570 bool found = look_for_barrier(n, post_parse, visited); 1571 if (!found) { 1572 n->dump(1); 1573 n->dump(-3); 1574 stringStream ss; 1575 C->method()->print_short_name(&ss); 1576 tty->print_cr("-%s-", ss.as_string()); 1577 assert(found, ""); 1578 } 1579 } 1580 } 1581 } 1582 } 1583 1584 #endif 1585 1586 bool ZBarrierSetC2::escape_add_to_con_graph(ConnectionGraph* conn_graph, PhaseGVN* gvn, Unique_Node_List* delayed_worklist, Node* n, uint opcode) const { 1587 switch (opcode) { 1588 case Op_LoadBarrierSlowReg: 1589 case Op_LoadBarrierWeakSlowReg: 1590 conn_graph->add_objload_to_connection_graph(n, delayed_worklist); 1591 return true; 1592 case Op_Proj: 1593 if (n->as_Proj()->_con == LoadBarrierNode::Oop && n->in(0)->is_LoadBarrier()) { 1594 conn_graph->add_local_var_and_edge(n, PointsToNode::NoEscape, n->in(0)->in(LoadBarrierNode::Oop), 1595 delayed_worklist); 1596 return true; 1597 } 1598 default: 1599 break; 1600 } 1601 return false; 1602 } 1603 1604 bool ZBarrierSetC2::escape_add_final_edges(ConnectionGraph* conn_graph, PhaseGVN* gvn, Node* n, uint opcode) const { 1605 switch (opcode) { 1606 case Op_LoadBarrierSlowReg: 1607 case Op_LoadBarrierWeakSlowReg: { 1608 const Type *t = gvn->type(n); 1609 if (t->make_ptr() != NULL) { 1610 Node *adr = n->in(MemNode::Address); 1611 conn_graph->add_local_var_and_edge(n, PointsToNode::NoEscape, adr, NULL); 1612 return true; 1613 } 1614 } 1615 case Op_Proj: { 1616 if (n->as_Proj()->_con == LoadBarrierNode::Oop && n->in(0)->is_LoadBarrier()) { 1617 conn_graph->add_local_var_and_edge(n, PointsToNode::NoEscape, n->in(0)->in(LoadBarrierNode::Oop), NULL); 1618 return true; 1619 } 1620 } 1621 default: 1622 break; 1623 } 1624 return false; 1625 }