1 /* 2 * Copyright (c) 2018, 2019, Red Hat, Inc. All rights reserved. 3 * 4 * This code is free software; you can redistribute it and/or modify it 5 * under the terms of the GNU General Public License version 2 only, as 6 * published by the Free Software Foundation. 7 * 8 * This code is distributed in the hope that it will be useful, but WITHOUT 9 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 10 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 11 * version 2 for more details (a copy is included in the LICENSE file that 12 * accompanied this code). 13 * 14 * You should have received a copy of the GNU General Public License version 15 * 2 along with this work; if not, write to the Free Software Foundation, 16 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. 17 * 18 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA 19 * or visit www.oracle.com if you need additional information or have any 20 * questions. 21 * 22 */ 23 24 #include "precompiled.hpp" 25 #include "gc/shared/barrierSet.hpp" 26 #include "gc/shenandoah/shenandoahForwarding.hpp" 27 #include "gc/shenandoah/shenandoahHeap.hpp" 28 #include "gc/shenandoah/shenandoahHeuristics.hpp" 29 #include "gc/shenandoah/shenandoahRuntime.hpp" 30 #include "gc/shenandoah/shenandoahThreadLocalData.hpp" 31 #include "gc/shenandoah/c2/shenandoahBarrierSetC2.hpp" 32 #include "gc/shenandoah/c2/shenandoahSupport.hpp" 33 #include "opto/arraycopynode.hpp" 34 #include "opto/escape.hpp" 35 #include "opto/graphKit.hpp" 36 #include "opto/idealKit.hpp" 37 #include "opto/macro.hpp" 38 #include "opto/movenode.hpp" 39 #include "opto/narrowptrnode.hpp" 40 #include "opto/rootnode.hpp" 41 42 ShenandoahBarrierSetC2* ShenandoahBarrierSetC2::bsc2() { 43 return reinterpret_cast<ShenandoahBarrierSetC2*>(BarrierSet::barrier_set()->barrier_set_c2()); 44 } 45 46 ShenandoahBarrierSetC2State::ShenandoahBarrierSetC2State(Arena* comp_arena) 47 : _enqueue_barriers(new (comp_arena) GrowableArray<ShenandoahEnqueueBarrierNode*>(comp_arena, 8, 0, NULL)), 48 _load_reference_barriers(new (comp_arena) GrowableArray<ShenandoahLoadReferenceBarrierNode*>(comp_arena, 8, 0, NULL)) { 49 } 50 51 int ShenandoahBarrierSetC2State::enqueue_barriers_count() const { 52 return _enqueue_barriers->length(); 53 } 54 55 ShenandoahEnqueueBarrierNode* ShenandoahBarrierSetC2State::enqueue_barrier(int idx) const { 56 return _enqueue_barriers->at(idx); 57 } 58 59 void ShenandoahBarrierSetC2State::add_enqueue_barrier(ShenandoahEnqueueBarrierNode * n) { 60 assert(!_enqueue_barriers->contains(n), "duplicate entry in barrier list"); 61 _enqueue_barriers->append(n); 62 } 63 64 void ShenandoahBarrierSetC2State::remove_enqueue_barrier(ShenandoahEnqueueBarrierNode * n) { 65 if (_enqueue_barriers->contains(n)) { 66 _enqueue_barriers->remove(n); 67 } 68 } 69 70 int ShenandoahBarrierSetC2State::load_reference_barriers_count() const { 71 return _load_reference_barriers->length(); 72 } 73 74 ShenandoahLoadReferenceBarrierNode* ShenandoahBarrierSetC2State::load_reference_barrier(int idx) const { 75 return _load_reference_barriers->at(idx); 76 } 77 78 void ShenandoahBarrierSetC2State::add_load_reference_barrier(ShenandoahLoadReferenceBarrierNode * n) { 79 assert(!_load_reference_barriers->contains(n), "duplicate entry in barrier list"); 80 _load_reference_barriers->append(n); 81 } 82 83 void ShenandoahBarrierSetC2State::remove_load_reference_barrier(ShenandoahLoadReferenceBarrierNode * n) { 84 if (_load_reference_barriers->contains(n)) { 85 _load_reference_barriers->remove(n); 86 } 87 } 88 89 Node* ShenandoahBarrierSetC2::shenandoah_storeval_barrier(GraphKit* kit, Node* obj) const { 90 if (ShenandoahStoreValEnqueueBarrier) { 91 obj = shenandoah_enqueue_barrier(kit, obj); 92 } 93 return obj; 94 } 95 96 #define __ kit-> 97 98 bool ShenandoahBarrierSetC2::satb_can_remove_pre_barrier(GraphKit* kit, PhaseTransform* phase, Node* adr, 99 BasicType bt, uint adr_idx) const { 100 intptr_t offset = 0; 101 Node* base = AddPNode::Ideal_base_and_offset(adr, phase, offset); 102 AllocateNode* alloc = AllocateNode::Ideal_allocation(base, phase); 103 104 if (offset == Type::OffsetBot) { 105 return false; // cannot unalias unless there are precise offsets 106 } 107 108 if (alloc == NULL) { 109 return false; // No allocation found 110 } 111 112 intptr_t size_in_bytes = type2aelembytes(bt); 113 114 Node* mem = __ memory(adr_idx); // start searching here... 115 116 for (int cnt = 0; cnt < 50; cnt++) { 117 118 if (mem->is_Store()) { 119 120 Node* st_adr = mem->in(MemNode::Address); 121 intptr_t st_offset = 0; 122 Node* st_base = AddPNode::Ideal_base_and_offset(st_adr, phase, st_offset); 123 124 if (st_base == NULL) { 125 break; // inscrutable pointer 126 } 127 128 // Break we have found a store with same base and offset as ours so break 129 if (st_base == base && st_offset == offset) { 130 break; 131 } 132 133 if (st_offset != offset && st_offset != Type::OffsetBot) { 134 const int MAX_STORE = BytesPerLong; 135 if (st_offset >= offset + size_in_bytes || 136 st_offset <= offset - MAX_STORE || 137 st_offset <= offset - mem->as_Store()->memory_size()) { 138 // Success: The offsets are provably independent. 139 // (You may ask, why not just test st_offset != offset and be done? 140 // The answer is that stores of different sizes can co-exist 141 // in the same sequence of RawMem effects. We sometimes initialize 142 // a whole 'tile' of array elements with a single jint or jlong.) 143 mem = mem->in(MemNode::Memory); 144 continue; // advance through independent store memory 145 } 146 } 147 148 if (st_base != base 149 && MemNode::detect_ptr_independence(base, alloc, st_base, 150 AllocateNode::Ideal_allocation(st_base, phase), 151 phase)) { 152 // Success: The bases are provably independent. 153 mem = mem->in(MemNode::Memory); 154 continue; // advance through independent store memory 155 } 156 } else if (mem->is_Proj() && mem->in(0)->is_Initialize()) { 157 158 InitializeNode* st_init = mem->in(0)->as_Initialize(); 159 AllocateNode* st_alloc = st_init->allocation(); 160 161 // Make sure that we are looking at the same allocation site. 162 // The alloc variable is guaranteed to not be null here from earlier check. 163 if (alloc == st_alloc) { 164 // Check that the initialization is storing NULL so that no previous store 165 // has been moved up and directly write a reference 166 Node* captured_store = st_init->find_captured_store(offset, 167 type2aelembytes(T_OBJECT), 168 phase); 169 if (captured_store == NULL || captured_store == st_init->zero_memory()) { 170 return true; 171 } 172 } 173 } 174 175 // Unless there is an explicit 'continue', we must bail out here, 176 // because 'mem' is an inscrutable memory state (e.g., a call). 177 break; 178 } 179 180 return false; 181 } 182 183 #undef __ 184 #define __ ideal. 185 186 void ShenandoahBarrierSetC2::satb_write_barrier_pre(GraphKit* kit, 187 bool do_load, 188 Node* obj, 189 Node* adr, 190 uint alias_idx, 191 Node* val, 192 const TypeOopPtr* val_type, 193 Node* pre_val, 194 BasicType bt) const { 195 // Some sanity checks 196 // Note: val is unused in this routine. 197 198 if (do_load) { 199 // We need to generate the load of the previous value 200 assert(obj != NULL, "must have a base"); 201 assert(adr != NULL, "where are loading from?"); 202 assert(pre_val == NULL, "loaded already?"); 203 assert(val_type != NULL, "need a type"); 204 205 if (ReduceInitialCardMarks 206 && satb_can_remove_pre_barrier(kit, &kit->gvn(), adr, bt, alias_idx)) { 207 return; 208 } 209 210 } else { 211 // In this case both val_type and alias_idx are unused. 212 assert(pre_val != NULL, "must be loaded already"); 213 // Nothing to be done if pre_val is null. 214 if (pre_val->bottom_type() == TypePtr::NULL_PTR) return; 215 assert(pre_val->bottom_type()->basic_type() == T_OBJECT, "or we shouldn't be here"); 216 } 217 assert(bt == T_OBJECT, "or we shouldn't be here"); 218 219 IdealKit ideal(kit, true); 220 221 Node* tls = __ thread(); // ThreadLocalStorage 222 223 Node* no_base = __ top(); 224 Node* zero = __ ConI(0); 225 Node* zeroX = __ ConX(0); 226 227 float likely = PROB_LIKELY(0.999); 228 float unlikely = PROB_UNLIKELY(0.999); 229 230 // Offsets into the thread 231 const int index_offset = in_bytes(ShenandoahThreadLocalData::satb_mark_queue_index_offset()); 232 const int buffer_offset = in_bytes(ShenandoahThreadLocalData::satb_mark_queue_buffer_offset()); 233 234 // Now the actual pointers into the thread 235 Node* buffer_adr = __ AddP(no_base, tls, __ ConX(buffer_offset)); 236 Node* index_adr = __ AddP(no_base, tls, __ ConX(index_offset)); 237 238 // Now some of the values 239 Node* marking; 240 Node* gc_state = __ AddP(no_base, tls, __ ConX(in_bytes(ShenandoahThreadLocalData::gc_state_offset()))); 241 Node* ld = __ load(__ ctrl(), gc_state, TypeInt::BYTE, T_BYTE, Compile::AliasIdxRaw); 242 marking = __ AndI(ld, __ ConI(ShenandoahHeap::MARKING)); 243 assert(ShenandoahBarrierC2Support::is_gc_state_load(ld), "Should match the shape"); 244 245 // if (!marking) 246 __ if_then(marking, BoolTest::ne, zero, unlikely); { 247 BasicType index_bt = TypeX_X->basic_type(); 248 assert(sizeof(size_t) == type2aelembytes(index_bt), "Loading G1 SATBMarkQueue::_index with wrong size."); 249 Node* index = __ load(__ ctrl(), index_adr, TypeX_X, index_bt, Compile::AliasIdxRaw); 250 251 if (do_load) { 252 // load original value 253 // alias_idx correct?? 254 pre_val = __ load(__ ctrl(), adr, val_type, bt, alias_idx); 255 } 256 257 // if (pre_val != NULL) 258 __ if_then(pre_val, BoolTest::ne, kit->null()); { 259 Node* buffer = __ load(__ ctrl(), buffer_adr, TypeRawPtr::NOTNULL, T_ADDRESS, Compile::AliasIdxRaw); 260 261 // is the queue for this thread full? 262 __ if_then(index, BoolTest::ne, zeroX, likely); { 263 264 // decrement the index 265 Node* next_index = kit->gvn().transform(new SubXNode(index, __ ConX(sizeof(intptr_t)))); 266 267 // Now get the buffer location we will log the previous value into and store it 268 Node *log_addr = __ AddP(no_base, buffer, next_index); 269 __ store(__ ctrl(), log_addr, pre_val, T_OBJECT, Compile::AliasIdxRaw, MemNode::unordered); 270 // update the index 271 __ store(__ ctrl(), index_adr, next_index, index_bt, Compile::AliasIdxRaw, MemNode::unordered); 272 273 } __ else_(); { 274 275 // logging buffer is full, call the runtime 276 const TypeFunc *tf = ShenandoahBarrierSetC2::write_ref_field_pre_entry_Type(); 277 __ make_leaf_call(tf, CAST_FROM_FN_PTR(address, ShenandoahRuntime::write_ref_field_pre_entry), "shenandoah_wb_pre", pre_val, tls); 278 } __ end_if(); // (!index) 279 } __ end_if(); // (pre_val != NULL) 280 } __ end_if(); // (!marking) 281 282 // Final sync IdealKit and GraphKit. 283 kit->final_sync(ideal); 284 285 if (ShenandoahSATBBarrier && adr != NULL) { 286 Node* c = kit->control(); 287 Node* call = c->in(1)->in(1)->in(1)->in(0); 288 assert(is_shenandoah_wb_pre_call(call), "shenandoah_wb_pre call expected"); 289 call->add_req(adr); 290 } 291 } 292 293 bool ShenandoahBarrierSetC2::is_shenandoah_wb_pre_call(Node* call) { 294 return call->is_CallLeaf() && 295 call->as_CallLeaf()->entry_point() == CAST_FROM_FN_PTR(address, ShenandoahRuntime::write_ref_field_pre_entry); 296 } 297 298 bool ShenandoahBarrierSetC2::is_shenandoah_lrb_call(Node* call) { 299 return call->is_CallLeaf() && 300 call->as_CallLeaf()->entry_point() == CAST_FROM_FN_PTR(address, ShenandoahRuntime::load_reference_barrier); 301 } 302 303 bool ShenandoahBarrierSetC2::is_shenandoah_marking_if(PhaseTransform *phase, Node* n) { 304 if (n->Opcode() != Op_If) { 305 return false; 306 } 307 308 Node* bol = n->in(1); 309 assert(bol->is_Bool(), ""); 310 Node* cmpx = bol->in(1); 311 if (bol->as_Bool()->_test._test == BoolTest::ne && 312 cmpx->is_Cmp() && cmpx->in(2) == phase->intcon(0) && 313 is_shenandoah_state_load(cmpx->in(1)->in(1)) && 314 cmpx->in(1)->in(2)->is_Con() && 315 cmpx->in(1)->in(2) == phase->intcon(ShenandoahHeap::MARKING)) { 316 return true; 317 } 318 319 return false; 320 } 321 322 bool ShenandoahBarrierSetC2::is_shenandoah_state_load(Node* n) { 323 if (!n->is_Load()) return false; 324 const int state_offset = in_bytes(ShenandoahThreadLocalData::gc_state_offset()); 325 return n->in(2)->is_AddP() && n->in(2)->in(2)->Opcode() == Op_ThreadLocal 326 && n->in(2)->in(3)->is_Con() 327 && n->in(2)->in(3)->bottom_type()->is_intptr_t()->get_con() == state_offset; 328 } 329 330 void ShenandoahBarrierSetC2::shenandoah_write_barrier_pre(GraphKit* kit, 331 bool do_load, 332 Node* obj, 333 Node* adr, 334 uint alias_idx, 335 Node* val, 336 const TypeOopPtr* val_type, 337 Node* pre_val, 338 BasicType bt) const { 339 if (ShenandoahSATBBarrier) { 340 IdealKit ideal(kit); 341 kit->sync_kit(ideal); 342 343 satb_write_barrier_pre(kit, do_load, obj, adr, alias_idx, val, val_type, pre_val, bt); 344 345 ideal.sync_kit(kit); 346 kit->final_sync(ideal); 347 } 348 } 349 350 Node* ShenandoahBarrierSetC2::shenandoah_enqueue_barrier(GraphKit* kit, Node* pre_val) const { 351 return kit->gvn().transform(new ShenandoahEnqueueBarrierNode(pre_val)); 352 } 353 354 // Helper that guards and inserts a pre-barrier. 355 void ShenandoahBarrierSetC2::insert_pre_barrier(GraphKit* kit, Node* base_oop, Node* offset, 356 Node* pre_val, bool need_mem_bar) const { 357 // We could be accessing the referent field of a reference object. If so, when G1 358 // is enabled, we need to log the value in the referent field in an SATB buffer. 359 // This routine performs some compile time filters and generates suitable 360 // runtime filters that guard the pre-barrier code. 361 // Also add memory barrier for non volatile load from the referent field 362 // to prevent commoning of loads across safepoint. 363 364 // Some compile time checks. 365 366 // If offset is a constant, is it java_lang_ref_Reference::_reference_offset? 367 const TypeX* otype = offset->find_intptr_t_type(); 368 if (otype != NULL && otype->is_con() && 369 otype->get_con() != java_lang_ref_Reference::referent_offset) { 370 // Constant offset but not the reference_offset so just return 371 return; 372 } 373 374 // We only need to generate the runtime guards for instances. 375 const TypeOopPtr* btype = base_oop->bottom_type()->isa_oopptr(); 376 if (btype != NULL) { 377 if (btype->isa_aryptr()) { 378 // Array type so nothing to do 379 return; 380 } 381 382 const TypeInstPtr* itype = btype->isa_instptr(); 383 if (itype != NULL) { 384 // Can the klass of base_oop be statically determined to be 385 // _not_ a sub-class of Reference and _not_ Object? 386 ciKlass* klass = itype->klass(); 387 if ( klass->is_loaded() && 388 !klass->is_subtype_of(kit->env()->Reference_klass()) && 389 !kit->env()->Object_klass()->is_subtype_of(klass)) { 390 return; 391 } 392 } 393 } 394 395 // The compile time filters did not reject base_oop/offset so 396 // we need to generate the following runtime filters 397 // 398 // if (offset == java_lang_ref_Reference::_reference_offset) { 399 // if (instance_of(base, java.lang.ref.Reference)) { 400 // pre_barrier(_, pre_val, ...); 401 // } 402 // } 403 404 float likely = PROB_LIKELY( 0.999); 405 float unlikely = PROB_UNLIKELY(0.999); 406 407 IdealKit ideal(kit); 408 409 Node* referent_off = __ ConX(java_lang_ref_Reference::referent_offset); 410 411 __ if_then(offset, BoolTest::eq, referent_off, unlikely); { 412 // Update graphKit memory and control from IdealKit. 413 kit->sync_kit(ideal); 414 415 Node* ref_klass_con = kit->makecon(TypeKlassPtr::make(kit->env()->Reference_klass())); 416 Node* is_instof = kit->gen_instanceof(base_oop, ref_klass_con); 417 418 // Update IdealKit memory and control from graphKit. 419 __ sync_kit(kit); 420 421 Node* one = __ ConI(1); 422 // is_instof == 0 if base_oop == NULL 423 __ if_then(is_instof, BoolTest::eq, one, unlikely); { 424 425 // Update graphKit from IdeakKit. 426 kit->sync_kit(ideal); 427 428 // Use the pre-barrier to record the value in the referent field 429 satb_write_barrier_pre(kit, false /* do_load */, 430 NULL /* obj */, NULL /* adr */, max_juint /* alias_idx */, NULL /* val */, NULL /* val_type */, 431 pre_val /* pre_val */, 432 T_OBJECT); 433 if (need_mem_bar) { 434 // Add memory barrier to prevent commoning reads from this field 435 // across safepoint since GC can change its value. 436 kit->insert_mem_bar(Op_MemBarCPUOrder); 437 } 438 // Update IdealKit from graphKit. 439 __ sync_kit(kit); 440 441 } __ end_if(); // _ref_type != ref_none 442 } __ end_if(); // offset == referent_offset 443 444 // Final sync IdealKit and GraphKit. 445 kit->final_sync(ideal); 446 } 447 448 #undef __ 449 450 const TypeFunc* ShenandoahBarrierSetC2::write_ref_field_pre_entry_Type() { 451 const Type **fields = TypeTuple::fields(2); 452 fields[TypeFunc::Parms+0] = TypeInstPtr::NOTNULL; // original field value 453 fields[TypeFunc::Parms+1] = TypeRawPtr::NOTNULL; // thread 454 const TypeTuple *domain = TypeTuple::make(TypeFunc::Parms+2, fields); 455 456 // create result type (range) 457 fields = TypeTuple::fields(0); 458 const TypeTuple *range = TypeTuple::make(TypeFunc::Parms+0, fields); 459 460 return TypeFunc::make(domain, range); 461 } 462 463 const TypeFunc* ShenandoahBarrierSetC2::shenandoah_clone_barrier_Type() { 464 const Type **fields = TypeTuple::fields(1); 465 fields[TypeFunc::Parms+0] = TypeInstPtr::NOTNULL; // original field value 466 const TypeTuple *domain = TypeTuple::make(TypeFunc::Parms+1, fields); 467 468 // create result type (range) 469 fields = TypeTuple::fields(0); 470 const TypeTuple *range = TypeTuple::make(TypeFunc::Parms+0, fields); 471 472 return TypeFunc::make(domain, range); 473 } 474 475 const TypeFunc* ShenandoahBarrierSetC2::shenandoah_load_reference_barrier_Type() { 476 const Type **fields = TypeTuple::fields(1); 477 fields[TypeFunc::Parms+0] = TypeInstPtr::NOTNULL; // original field value 478 const TypeTuple *domain = TypeTuple::make(TypeFunc::Parms+1, fields); 479 480 // create result type (range) 481 fields = TypeTuple::fields(1); 482 fields[TypeFunc::Parms+0] = TypeInstPtr::NOTNULL; 483 const TypeTuple *range = TypeTuple::make(TypeFunc::Parms+1, fields); 484 485 return TypeFunc::make(domain, range); 486 } 487 488 Node* ShenandoahBarrierSetC2::store_at_resolved(C2Access& access, C2AccessValue& val) const { 489 DecoratorSet decorators = access.decorators(); 490 491 const TypePtr* adr_type = access.addr().type(); 492 Node* adr = access.addr().node(); 493 494 bool anonymous = (decorators & ON_UNKNOWN_OOP_REF) != 0; 495 bool on_heap = (decorators & IN_HEAP) != 0; 496 497 if (!access.is_oop() || (!on_heap && !anonymous)) { 498 return BarrierSetC2::store_at_resolved(access, val); 499 } 500 501 if (access.is_parse_access()) { 502 C2ParseAccess& parse_access = static_cast<C2ParseAccess&>(access); 503 GraphKit* kit = parse_access.kit(); 504 505 uint adr_idx = kit->C->get_alias_index(adr_type); 506 assert(adr_idx != Compile::AliasIdxTop, "use other store_to_memory factory" ); 507 Node* value = val.node(); 508 value = shenandoah_storeval_barrier(kit, value); 509 val.set_node(value); 510 shenandoah_write_barrier_pre(kit, true /* do_load */, /*kit->control(),*/ access.base(), adr, adr_idx, val.node(), 511 static_cast<const TypeOopPtr*>(val.type()), NULL /* pre_val */, access.type()); 512 } else { 513 assert(access.is_opt_access(), "only for optimization passes"); 514 assert(((decorators & C2_TIGHTLY_COUPLED_ALLOC) != 0 || !ShenandoahSATBBarrier) && (decorators & C2_ARRAY_COPY) != 0, "unexpected caller of this code"); 515 C2OptAccess& opt_access = static_cast<C2OptAccess&>(access); 516 PhaseGVN& gvn = opt_access.gvn(); 517 MergeMemNode* mm = opt_access.mem(); 518 519 if (ShenandoahStoreValEnqueueBarrier) { 520 Node* enqueue = gvn.transform(new ShenandoahEnqueueBarrierNode(val.node())); 521 val.set_node(enqueue); 522 } 523 } 524 return BarrierSetC2::store_at_resolved(access, val); 525 } 526 527 Node* ShenandoahBarrierSetC2::load_at_resolved(C2Access& access, const Type* val_type) const { 528 DecoratorSet decorators = access.decorators(); 529 530 Node* adr = access.addr().node(); 531 Node* obj = access.base(); 532 533 bool mismatched = (decorators & C2_MISMATCHED) != 0; 534 bool unknown = (decorators & ON_UNKNOWN_OOP_REF) != 0; 535 bool on_heap = (decorators & IN_HEAP) != 0; 536 bool on_weak = (decorators & ON_WEAK_OOP_REF) != 0; 537 bool is_unordered = (decorators & MO_UNORDERED) != 0; 538 bool need_cpu_mem_bar = !is_unordered || mismatched || !on_heap; 539 540 Node* top = Compile::current()->top(); 541 542 Node* offset = adr->is_AddP() ? adr->in(AddPNode::Offset) : top; 543 Node* load = BarrierSetC2::load_at_resolved(access, val_type); 544 545 if (access.is_oop()) { 546 if (ShenandoahLoadRefBarrier) { 547 load = new ShenandoahLoadReferenceBarrierNode(NULL, load, (decorators & IN_NATIVE) != 0); 548 if (access.is_parse_access()) { 549 load = static_cast<C2ParseAccess &>(access).kit()->gvn().transform(load); 550 } else { 551 load = static_cast<C2OptAccess &>(access).gvn().transform(load); 552 } 553 } 554 } 555 556 // If we are reading the value of the referent field of a Reference 557 // object (either by using Unsafe directly or through reflection) 558 // then, if SATB is enabled, we need to record the referent in an 559 // SATB log buffer using the pre-barrier mechanism. 560 // Also we need to add memory barrier to prevent commoning reads 561 // from this field across safepoint since GC can change its value. 562 bool need_read_barrier = ShenandoahKeepAliveBarrier && 563 (on_heap && (on_weak || (unknown && offset != top && obj != top))); 564 565 if (!access.is_oop() || !need_read_barrier) { 566 return load; 567 } 568 569 assert(access.is_parse_access(), "entry not supported at optimization time"); 570 C2ParseAccess& parse_access = static_cast<C2ParseAccess&>(access); 571 GraphKit* kit = parse_access.kit(); 572 573 if (on_weak) { 574 // Use the pre-barrier to record the value in the referent field 575 satb_write_barrier_pre(kit, false /* do_load */, 576 NULL /* obj */, NULL /* adr */, max_juint /* alias_idx */, NULL /* val */, NULL /* val_type */, 577 load /* pre_val */, T_OBJECT); 578 // Add memory barrier to prevent commoning reads from this field 579 // across safepoint since GC can change its value. 580 kit->insert_mem_bar(Op_MemBarCPUOrder); 581 } else if (unknown) { 582 // We do not require a mem bar inside pre_barrier if need_mem_bar 583 // is set: the barriers would be emitted by us. 584 insert_pre_barrier(kit, obj, offset, load, !need_cpu_mem_bar); 585 } 586 587 return load; 588 } 589 590 Node* ShenandoahBarrierSetC2::atomic_cmpxchg_val_at_resolved(C2AtomicParseAccess& access, Node* expected_val, 591 Node* new_val, const Type* value_type) const { 592 GraphKit* kit = access.kit(); 593 if (access.is_oop()) { 594 new_val = shenandoah_storeval_barrier(kit, new_val); 595 shenandoah_write_barrier_pre(kit, false /* do_load */, 596 NULL, NULL, max_juint, NULL, NULL, 597 expected_val /* pre_val */, T_OBJECT); 598 599 MemNode::MemOrd mo = access.mem_node_mo(); 600 Node* mem = access.memory(); 601 Node* adr = access.addr().node(); 602 const TypePtr* adr_type = access.addr().type(); 603 Node* load_store = NULL; 604 605 #ifdef _LP64 606 if (adr->bottom_type()->is_ptr_to_narrowoop()) { 607 Node *newval_enc = kit->gvn().transform(new EncodePNode(new_val, new_val->bottom_type()->make_narrowoop())); 608 Node *oldval_enc = kit->gvn().transform(new EncodePNode(expected_val, expected_val->bottom_type()->make_narrowoop())); 609 if (ShenandoahCASBarrier) { 610 load_store = kit->gvn().transform(new ShenandoahCompareAndExchangeNNode(kit->control(), mem, adr, newval_enc, oldval_enc, adr_type, value_type->make_narrowoop(), mo)); 611 } else { 612 load_store = kit->gvn().transform(new CompareAndExchangeNNode(kit->control(), mem, adr, newval_enc, oldval_enc, adr_type, value_type->make_narrowoop(), mo)); 613 } 614 } else 615 #endif 616 { 617 if (ShenandoahCASBarrier) { 618 load_store = kit->gvn().transform(new ShenandoahCompareAndExchangePNode(kit->control(), mem, adr, new_val, expected_val, adr_type, value_type->is_oopptr(), mo)); 619 } else { 620 load_store = kit->gvn().transform(new CompareAndExchangePNode(kit->control(), mem, adr, new_val, expected_val, adr_type, value_type->is_oopptr(), mo)); 621 } 622 } 623 624 access.set_raw_access(load_store); 625 pin_atomic_op(access); 626 627 #ifdef _LP64 628 if (adr->bottom_type()->is_ptr_to_narrowoop()) { 629 load_store = kit->gvn().transform(new DecodeNNode(load_store, load_store->get_ptr_type())); 630 } 631 #endif 632 load_store = kit->gvn().transform(new ShenandoahLoadReferenceBarrierNode(NULL, load_store, false)); 633 return load_store; 634 } 635 return BarrierSetC2::atomic_cmpxchg_val_at_resolved(access, expected_val, new_val, value_type); 636 } 637 638 Node* ShenandoahBarrierSetC2::atomic_cmpxchg_bool_at_resolved(C2AtomicParseAccess& access, Node* expected_val, 639 Node* new_val, const Type* value_type) const { 640 GraphKit* kit = access.kit(); 641 if (access.is_oop()) { 642 new_val = shenandoah_storeval_barrier(kit, new_val); 643 shenandoah_write_barrier_pre(kit, false /* do_load */, 644 NULL, NULL, max_juint, NULL, NULL, 645 expected_val /* pre_val */, T_OBJECT); 646 DecoratorSet decorators = access.decorators(); 647 MemNode::MemOrd mo = access.mem_node_mo(); 648 Node* mem = access.memory(); 649 bool is_weak_cas = (decorators & C2_WEAK_CMPXCHG) != 0; 650 Node* load_store = NULL; 651 Node* adr = access.addr().node(); 652 #ifdef _LP64 653 if (adr->bottom_type()->is_ptr_to_narrowoop()) { 654 Node *newval_enc = kit->gvn().transform(new EncodePNode(new_val, new_val->bottom_type()->make_narrowoop())); 655 Node *oldval_enc = kit->gvn().transform(new EncodePNode(expected_val, expected_val->bottom_type()->make_narrowoop())); 656 if (ShenandoahCASBarrier) { 657 if (is_weak_cas) { 658 load_store = kit->gvn().transform(new ShenandoahWeakCompareAndSwapNNode(kit->control(), mem, adr, newval_enc, oldval_enc, mo)); 659 } else { 660 load_store = kit->gvn().transform(new ShenandoahCompareAndSwapNNode(kit->control(), mem, adr, newval_enc, oldval_enc, mo)); 661 } 662 } else { 663 if (is_weak_cas) { 664 load_store = kit->gvn().transform(new WeakCompareAndSwapNNode(kit->control(), mem, adr, newval_enc, oldval_enc, mo)); 665 } else { 666 load_store = kit->gvn().transform(new CompareAndSwapNNode(kit->control(), mem, adr, newval_enc, oldval_enc, mo)); 667 } 668 } 669 } else 670 #endif 671 { 672 if (ShenandoahCASBarrier) { 673 if (is_weak_cas) { 674 load_store = kit->gvn().transform(new ShenandoahWeakCompareAndSwapPNode(kit->control(), mem, adr, new_val, expected_val, mo)); 675 } else { 676 load_store = kit->gvn().transform(new ShenandoahCompareAndSwapPNode(kit->control(), mem, adr, new_val, expected_val, mo)); 677 } 678 } else { 679 if (is_weak_cas) { 680 load_store = kit->gvn().transform(new WeakCompareAndSwapPNode(kit->control(), mem, adr, new_val, expected_val, mo)); 681 } else { 682 load_store = kit->gvn().transform(new CompareAndSwapPNode(kit->control(), mem, adr, new_val, expected_val, mo)); 683 } 684 } 685 } 686 access.set_raw_access(load_store); 687 pin_atomic_op(access); 688 return load_store; 689 } 690 return BarrierSetC2::atomic_cmpxchg_bool_at_resolved(access, expected_val, new_val, value_type); 691 } 692 693 Node* ShenandoahBarrierSetC2::atomic_xchg_at_resolved(C2AtomicParseAccess& access, Node* val, const Type* value_type) const { 694 GraphKit* kit = access.kit(); 695 if (access.is_oop()) { 696 val = shenandoah_storeval_barrier(kit, val); 697 } 698 Node* result = BarrierSetC2::atomic_xchg_at_resolved(access, val, value_type); 699 if (access.is_oop()) { 700 result = kit->gvn().transform(new ShenandoahLoadReferenceBarrierNode(NULL, result, false)); 701 shenandoah_write_barrier_pre(kit, false /* do_load */, 702 NULL, NULL, max_juint, NULL, NULL, 703 result /* pre_val */, T_OBJECT); 704 } 705 return result; 706 } 707 708 void ShenandoahBarrierSetC2::clone(GraphKit* kit, Node* src, Node* dst, Node* size, bool is_array) const { 709 assert(!src->is_AddP(), "unexpected input"); 710 BarrierSetC2::clone(kit, src, dst, size, is_array); 711 } 712 713 // Support for GC barriers emitted during parsing 714 bool ShenandoahBarrierSetC2::is_gc_barrier_node(Node* node) const { 715 if (node->Opcode() == Op_ShenandoahLoadReferenceBarrier) return true; 716 if (node->Opcode() != Op_CallLeaf && node->Opcode() != Op_CallLeafNoFP) { 717 return false; 718 } 719 CallLeafNode *call = node->as_CallLeaf(); 720 if (call->_name == NULL) { 721 return false; 722 } 723 724 return strcmp(call->_name, "shenandoah_clone_barrier") == 0 || 725 strcmp(call->_name, "shenandoah_cas_obj") == 0 || 726 strcmp(call->_name, "shenandoah_wb_pre") == 0; 727 } 728 729 Node* ShenandoahBarrierSetC2::step_over_gc_barrier(Node* c) const { 730 if (c->Opcode() == Op_ShenandoahLoadReferenceBarrier) { 731 return c->in(ShenandoahLoadReferenceBarrierNode::ValueIn); 732 } 733 if (c->Opcode() == Op_ShenandoahEnqueueBarrier) { 734 c = c->in(1); 735 } 736 return c; 737 } 738 739 bool ShenandoahBarrierSetC2::expand_barriers(Compile* C, PhaseIterGVN& igvn) const { 740 return !ShenandoahBarrierC2Support::expand(C, igvn); 741 } 742 743 bool ShenandoahBarrierSetC2::optimize_loops(PhaseIdealLoop* phase, LoopOptsMode mode, VectorSet& visited, Node_Stack& nstack, Node_List& worklist) const { 744 if (mode == LoopOptsShenandoahExpand) { 745 assert(UseShenandoahGC, "only for shenandoah"); 746 ShenandoahBarrierC2Support::pin_and_expand(phase); 747 return true; 748 } else if (mode == LoopOptsShenandoahPostExpand) { 749 assert(UseShenandoahGC, "only for shenandoah"); 750 visited.Clear(); 751 ShenandoahBarrierC2Support::optimize_after_expansion(visited, nstack, worklist, phase); 752 return true; 753 } 754 return false; 755 } 756 757 bool ShenandoahBarrierSetC2::array_copy_requires_gc_barriers(bool tightly_coupled_alloc, BasicType type, bool is_clone, ArrayCopyPhase phase) const { 758 bool is_oop = type == T_OBJECT || type == T_ARRAY; 759 if (!is_oop) { 760 return false; 761 } 762 if (tightly_coupled_alloc) { 763 if (phase == Optimization) { 764 return false; 765 } 766 return !is_clone; 767 } 768 if (phase == Optimization) { 769 return !ShenandoahStoreValEnqueueBarrier; 770 } 771 return true; 772 } 773 774 bool ShenandoahBarrierSetC2::clone_needs_postbarrier(ArrayCopyNode *ac, PhaseIterGVN& igvn) { 775 Node* src = ac->in(ArrayCopyNode::Src); 776 const TypeOopPtr* src_type = igvn.type(src)->is_oopptr(); 777 if (src_type->isa_instptr() != NULL) { 778 ciInstanceKlass* ik = src_type->klass()->as_instance_klass(); 779 if ((src_type->klass_is_exact() || (!ik->is_interface() && !ik->has_subklass())) && !ik->has_injected_fields()) { 780 if (ik->has_object_fields()) { 781 return true; 782 } else { 783 if (!src_type->klass_is_exact()) { 784 igvn.C->dependencies()->assert_leaf_type(ik); 785 } 786 } 787 } else { 788 return true; 789 } 790 } else if (src_type->isa_aryptr()) { 791 BasicType src_elem = src_type->klass()->as_array_klass()->element_type()->basic_type(); 792 if (src_elem == T_OBJECT || src_elem == T_ARRAY) { 793 return true; 794 } 795 } else { 796 return true; 797 } 798 return false; 799 } 800 801 void ShenandoahBarrierSetC2::clone_barrier_at_expansion(ArrayCopyNode* ac, Node* call, PhaseIterGVN& igvn) const { 802 assert(ac->is_clonebasic(), "no other kind of arraycopy here"); 803 804 if (!clone_needs_postbarrier(ac, igvn)) { 805 BarrierSetC2::clone_barrier_at_expansion(ac, call, igvn); 806 return; 807 } 808 809 const TypePtr* raw_adr_type = TypeRawPtr::BOTTOM; 810 Node* c = new ProjNode(call,TypeFunc::Control); 811 c = igvn.transform(c); 812 Node* m = new ProjNode(call, TypeFunc::Memory); 813 m = igvn.transform(m); 814 815 Node* dest = ac->in(ArrayCopyNode::Dest); 816 assert(dest->is_AddP(), "bad input"); 817 Node* barrier_call = new CallLeafNode(ShenandoahBarrierSetC2::shenandoah_clone_barrier_Type(), 818 CAST_FROM_FN_PTR(address, ShenandoahRuntime::shenandoah_clone_barrier), 819 "shenandoah_clone_barrier", raw_adr_type); 820 barrier_call->init_req(TypeFunc::Control, c); 821 barrier_call->init_req(TypeFunc::I_O , igvn.C->top()); 822 barrier_call->init_req(TypeFunc::Memory , m); 823 barrier_call->init_req(TypeFunc::ReturnAdr, igvn.C->top()); 824 barrier_call->init_req(TypeFunc::FramePtr, igvn.C->top()); 825 barrier_call->init_req(TypeFunc::Parms+0, dest->in(AddPNode::Base)); 826 827 barrier_call = igvn.transform(barrier_call); 828 c = new ProjNode(barrier_call,TypeFunc::Control); 829 c = igvn.transform(c); 830 m = new ProjNode(barrier_call, TypeFunc::Memory); 831 m = igvn.transform(m); 832 833 Node* out_c = ac->proj_out(TypeFunc::Control); 834 Node* out_m = ac->proj_out(TypeFunc::Memory); 835 igvn.replace_node(out_c, c); 836 igvn.replace_node(out_m, m); 837 } 838 839 840 // Support for macro expanded GC barriers 841 void ShenandoahBarrierSetC2::register_potential_barrier_node(Node* node) const { 842 if (node->Opcode() == Op_ShenandoahEnqueueBarrier) { 843 state()->add_enqueue_barrier((ShenandoahEnqueueBarrierNode*) node); 844 } 845 if (node->Opcode() == Op_ShenandoahLoadReferenceBarrier) { 846 state()->add_load_reference_barrier((ShenandoahLoadReferenceBarrierNode*) node); 847 } 848 } 849 850 void ShenandoahBarrierSetC2::unregister_potential_barrier_node(Node* node) const { 851 if (node->Opcode() == Op_ShenandoahEnqueueBarrier) { 852 state()->remove_enqueue_barrier((ShenandoahEnqueueBarrierNode*) node); 853 } 854 if (node->Opcode() == Op_ShenandoahLoadReferenceBarrier) { 855 state()->remove_load_reference_barrier((ShenandoahLoadReferenceBarrierNode*) node); 856 } 857 } 858 859 void ShenandoahBarrierSetC2::eliminate_gc_barrier(PhaseMacroExpand* macro, Node* n) const { 860 if (is_shenandoah_wb_pre_call(n)) { 861 shenandoah_eliminate_wb_pre(n, ¯o->igvn()); 862 } 863 } 864 865 void ShenandoahBarrierSetC2::shenandoah_eliminate_wb_pre(Node* call, PhaseIterGVN* igvn) const { 866 assert(UseShenandoahGC && is_shenandoah_wb_pre_call(call), ""); 867 Node* c = call->as_Call()->proj_out(TypeFunc::Control); 868 c = c->unique_ctrl_out(); 869 assert(c->is_Region() && c->req() == 3, "where's the pre barrier control flow?"); 870 c = c->unique_ctrl_out(); 871 assert(c->is_Region() && c->req() == 3, "where's the pre barrier control flow?"); 872 Node* iff = c->in(1)->is_IfProj() ? c->in(1)->in(0) : c->in(2)->in(0); 873 assert(iff->is_If(), "expect test"); 874 if (!is_shenandoah_marking_if(igvn, iff)) { 875 c = c->unique_ctrl_out(); 876 assert(c->is_Region() && c->req() == 3, "where's the pre barrier control flow?"); 877 iff = c->in(1)->is_IfProj() ? c->in(1)->in(0) : c->in(2)->in(0); 878 assert(is_shenandoah_marking_if(igvn, iff), "expect marking test"); 879 } 880 Node* cmpx = iff->in(1)->in(1); 881 igvn->replace_node(cmpx, igvn->makecon(TypeInt::CC_EQ)); 882 igvn->rehash_node_delayed(call); 883 call->del_req(call->req()-1); 884 } 885 886 void ShenandoahBarrierSetC2::enqueue_useful_gc_barrier(PhaseIterGVN* igvn, Node* node) const { 887 if (node->Opcode() == Op_AddP && ShenandoahBarrierSetC2::has_only_shenandoah_wb_pre_uses(node)) { 888 igvn->add_users_to_worklist(node); 889 } 890 } 891 892 void ShenandoahBarrierSetC2::eliminate_useless_gc_barriers(Unique_Node_List &useful, Compile* C) const { 893 for (uint i = 0; i < useful.size(); i++) { 894 Node* n = useful.at(i); 895 if (n->Opcode() == Op_AddP && ShenandoahBarrierSetC2::has_only_shenandoah_wb_pre_uses(n)) { 896 for (DUIterator_Fast imax, i = n->fast_outs(imax); i < imax; i++) { 897 C->record_for_igvn(n->fast_out(i)); 898 } 899 } 900 } 901 for (int i = state()->enqueue_barriers_count() - 1; i >= 0; i--) { 902 ShenandoahEnqueueBarrierNode* n = state()->enqueue_barrier(i); 903 if (!useful.member(n)) { 904 state()->remove_enqueue_barrier(n); 905 } 906 } 907 for (int i = state()->load_reference_barriers_count() - 1; i >= 0; i--) { 908 ShenandoahLoadReferenceBarrierNode* n = state()->load_reference_barrier(i); 909 if (!useful.member(n)) { 910 state()->remove_load_reference_barrier(n); 911 } 912 } 913 } 914 915 void* ShenandoahBarrierSetC2::create_barrier_state(Arena* comp_arena) const { 916 return new(comp_arena) ShenandoahBarrierSetC2State(comp_arena); 917 } 918 919 ShenandoahBarrierSetC2State* ShenandoahBarrierSetC2::state() const { 920 return reinterpret_cast<ShenandoahBarrierSetC2State*>(Compile::current()->barrier_set_state()); 921 } 922 923 // If the BarrierSetC2 state has kept macro nodes in its compilation unit state to be 924 // expanded later, then now is the time to do so. 925 bool ShenandoahBarrierSetC2::expand_macro_nodes(PhaseMacroExpand* macro) const { return false; } 926 927 #ifdef ASSERT 928 void ShenandoahBarrierSetC2::verify_gc_barriers(Compile* compile, CompilePhase phase) const { 929 if (ShenandoahVerifyOptoBarriers && phase == BarrierSetC2::BeforeMacroExpand) { 930 ShenandoahBarrierC2Support::verify(Compile::current()->root()); 931 } else if (phase == BarrierSetC2::BeforeCodeGen) { 932 // Verify G1 pre-barriers 933 const int marking_offset = in_bytes(ShenandoahThreadLocalData::satb_mark_queue_active_offset()); 934 935 ResourceArea *area = Thread::current()->resource_area(); 936 Unique_Node_List visited(area); 937 Node_List worklist(area); 938 // We're going to walk control flow backwards starting from the Root 939 worklist.push(compile->root()); 940 while (worklist.size() > 0) { 941 Node *x = worklist.pop(); 942 if (x == NULL || x == compile->top()) continue; 943 if (visited.member(x)) { 944 continue; 945 } else { 946 visited.push(x); 947 } 948 949 if (x->is_Region()) { 950 for (uint i = 1; i < x->req(); i++) { 951 worklist.push(x->in(i)); 952 } 953 } else { 954 worklist.push(x->in(0)); 955 // We are looking for the pattern: 956 // /->ThreadLocal 957 // If->Bool->CmpI->LoadB->AddP->ConL(marking_offset) 958 // \->ConI(0) 959 // We want to verify that the If and the LoadB have the same control 960 // See GraphKit::g1_write_barrier_pre() 961 if (x->is_If()) { 962 IfNode *iff = x->as_If(); 963 if (iff->in(1)->is_Bool() && iff->in(1)->in(1)->is_Cmp()) { 964 CmpNode *cmp = iff->in(1)->in(1)->as_Cmp(); 965 if (cmp->Opcode() == Op_CmpI && cmp->in(2)->is_Con() && cmp->in(2)->bottom_type()->is_int()->get_con() == 0 966 && cmp->in(1)->is_Load()) { 967 LoadNode *load = cmp->in(1)->as_Load(); 968 if (load->Opcode() == Op_LoadB && load->in(2)->is_AddP() && load->in(2)->in(2)->Opcode() == Op_ThreadLocal 969 && load->in(2)->in(3)->is_Con() 970 && load->in(2)->in(3)->bottom_type()->is_intptr_t()->get_con() == marking_offset) { 971 972 Node *if_ctrl = iff->in(0); 973 Node *load_ctrl = load->in(0); 974 975 if (if_ctrl != load_ctrl) { 976 // Skip possible CProj->NeverBranch in infinite loops 977 if ((if_ctrl->is_Proj() && if_ctrl->Opcode() == Op_CProj) 978 && (if_ctrl->in(0)->is_MultiBranch() && if_ctrl->in(0)->Opcode() == Op_NeverBranch)) { 979 if_ctrl = if_ctrl->in(0)->in(0); 980 } 981 } 982 assert(load_ctrl != NULL && if_ctrl == load_ctrl, "controls must match"); 983 } 984 } 985 } 986 } 987 } 988 } 989 } 990 } 991 #endif 992 993 Node* ShenandoahBarrierSetC2::ideal_node(PhaseGVN* phase, Node* n, bool can_reshape) const { 994 if (is_shenandoah_wb_pre_call(n)) { 995 uint cnt = ShenandoahBarrierSetC2::write_ref_field_pre_entry_Type()->domain()->cnt(); 996 if (n->req() > cnt) { 997 Node* addp = n->in(cnt); 998 if (has_only_shenandoah_wb_pre_uses(addp)) { 999 n->del_req(cnt); 1000 if (can_reshape) { 1001 phase->is_IterGVN()->_worklist.push(addp); 1002 } 1003 return n; 1004 } 1005 } 1006 } 1007 if (n->Opcode() == Op_CmpP) { 1008 Node* in1 = n->in(1); 1009 Node* in2 = n->in(2); 1010 if (in1->bottom_type() == TypePtr::NULL_PTR) { 1011 in2 = step_over_gc_barrier(in2); 1012 } 1013 if (in2->bottom_type() == TypePtr::NULL_PTR) { 1014 in1 = step_over_gc_barrier(in1); 1015 } 1016 PhaseIterGVN* igvn = phase->is_IterGVN(); 1017 if (in1 != n->in(1)) { 1018 if (igvn != NULL) { 1019 n->set_req_X(1, in1, igvn); 1020 } else { 1021 n->set_req(1, in1); 1022 } 1023 assert(in2 == n->in(2), "only one change"); 1024 return n; 1025 } 1026 if (in2 != n->in(2)) { 1027 if (igvn != NULL) { 1028 n->set_req_X(2, in2, igvn); 1029 } else { 1030 n->set_req(2, in2); 1031 } 1032 return n; 1033 } 1034 } else if (can_reshape && 1035 n->Opcode() == Op_If && 1036 ShenandoahBarrierC2Support::is_heap_stable_test(n) && 1037 n->in(0) != NULL) { 1038 Node* dom = n->in(0); 1039 Node* prev_dom = n; 1040 int op = n->Opcode(); 1041 int dist = 16; 1042 // Search up the dominator tree for another heap stable test 1043 while (dom->Opcode() != op || // Not same opcode? 1044 !ShenandoahBarrierC2Support::is_heap_stable_test(dom) || // Not same input 1? 1045 prev_dom->in(0) != dom) { // One path of test does not dominate? 1046 if (dist < 0) return NULL; 1047 1048 dist--; 1049 prev_dom = dom; 1050 dom = IfNode::up_one_dom(dom); 1051 if (!dom) return NULL; 1052 } 1053 1054 // Check that we did not follow a loop back to ourselves 1055 if (n == dom) { 1056 return NULL; 1057 } 1058 1059 return n->as_If()->dominated_by(prev_dom, phase->is_IterGVN()); 1060 } 1061 1062 return NULL; 1063 } 1064 1065 bool ShenandoahBarrierSetC2::has_only_shenandoah_wb_pre_uses(Node* n) { 1066 for (DUIterator_Fast imax, i = n->fast_outs(imax); i < imax; i++) { 1067 Node* u = n->fast_out(i); 1068 if (!is_shenandoah_wb_pre_call(u)) { 1069 return false; 1070 } 1071 } 1072 return n->outcnt() > 0; 1073 } 1074 1075 bool ShenandoahBarrierSetC2::final_graph_reshaping(Compile* compile, Node* n, uint opcode) const { 1076 switch (opcode) { 1077 case Op_CallLeaf: 1078 case Op_CallLeafNoFP: { 1079 assert (n->is_Call(), ""); 1080 CallNode *call = n->as_Call(); 1081 if (ShenandoahBarrierSetC2::is_shenandoah_wb_pre_call(call)) { 1082 uint cnt = ShenandoahBarrierSetC2::write_ref_field_pre_entry_Type()->domain()->cnt(); 1083 if (call->req() > cnt) { 1084 assert(call->req() == cnt + 1, "only one extra input"); 1085 Node *addp = call->in(cnt); 1086 assert(!ShenandoahBarrierSetC2::has_only_shenandoah_wb_pre_uses(addp), "useless address computation?"); 1087 call->del_req(cnt); 1088 } 1089 } 1090 return false; 1091 } 1092 case Op_ShenandoahCompareAndSwapP: 1093 case Op_ShenandoahCompareAndSwapN: 1094 case Op_ShenandoahWeakCompareAndSwapN: 1095 case Op_ShenandoahWeakCompareAndSwapP: 1096 case Op_ShenandoahCompareAndExchangeP: 1097 case Op_ShenandoahCompareAndExchangeN: 1098 #ifdef ASSERT 1099 if( VerifyOptoOopOffsets ) { 1100 MemNode* mem = n->as_Mem(); 1101 // Check to see if address types have grounded out somehow. 1102 const TypeInstPtr *tp = mem->in(MemNode::Address)->bottom_type()->isa_instptr(); 1103 ciInstanceKlass *k = tp->klass()->as_instance_klass(); 1104 bool oop_offset_is_sane = k->contains_field_offset(tp->offset()); 1105 assert( !tp || oop_offset_is_sane, "" ); 1106 } 1107 #endif 1108 return true; 1109 case Op_ShenandoahLoadReferenceBarrier: 1110 assert(false, "should have been expanded already"); 1111 return true; 1112 default: 1113 return false; 1114 } 1115 } 1116 1117 bool ShenandoahBarrierSetC2::escape_add_to_con_graph(ConnectionGraph* conn_graph, PhaseGVN* gvn, Unique_Node_List* delayed_worklist, Node* n, uint opcode) const { 1118 switch (opcode) { 1119 case Op_ShenandoahCompareAndExchangeP: 1120 case Op_ShenandoahCompareAndExchangeN: 1121 conn_graph->add_objload_to_connection_graph(n, delayed_worklist); 1122 // fallthrough 1123 case Op_ShenandoahWeakCompareAndSwapP: 1124 case Op_ShenandoahWeakCompareAndSwapN: 1125 case Op_ShenandoahCompareAndSwapP: 1126 case Op_ShenandoahCompareAndSwapN: 1127 conn_graph->add_to_congraph_unsafe_access(n, opcode, delayed_worklist); 1128 return true; 1129 case Op_StoreP: { 1130 Node* adr = n->in(MemNode::Address); 1131 const Type* adr_type = gvn->type(adr); 1132 // Pointer stores in G1 barriers looks like unsafe access. 1133 // Ignore such stores to be able scalar replace non-escaping 1134 // allocations. 1135 if (adr_type->isa_rawptr() && adr->is_AddP()) { 1136 Node* base = conn_graph->get_addp_base(adr); 1137 if (base->Opcode() == Op_LoadP && 1138 base->in(MemNode::Address)->is_AddP()) { 1139 adr = base->in(MemNode::Address); 1140 Node* tls = conn_graph->get_addp_base(adr); 1141 if (tls->Opcode() == Op_ThreadLocal) { 1142 int offs = (int) gvn->find_intptr_t_con(adr->in(AddPNode::Offset), Type::OffsetBot); 1143 const int buf_offset = in_bytes(ShenandoahThreadLocalData::satb_mark_queue_buffer_offset()); 1144 if (offs == buf_offset) { 1145 return true; // Pre barrier previous oop value store. 1146 } 1147 } 1148 } 1149 } 1150 return false; 1151 } 1152 case Op_ShenandoahEnqueueBarrier: 1153 conn_graph->add_local_var_and_edge(n, PointsToNode::NoEscape, n->in(1), delayed_worklist); 1154 break; 1155 case Op_ShenandoahLoadReferenceBarrier: 1156 conn_graph->add_local_var_and_edge(n, PointsToNode::NoEscape, n->in(ShenandoahLoadReferenceBarrierNode::ValueIn), delayed_worklist); 1157 return true; 1158 default: 1159 // Nothing 1160 break; 1161 } 1162 return false; 1163 } 1164 1165 bool ShenandoahBarrierSetC2::escape_add_final_edges(ConnectionGraph* conn_graph, PhaseGVN* gvn, Node* n, uint opcode) const { 1166 switch (opcode) { 1167 case Op_ShenandoahCompareAndExchangeP: 1168 case Op_ShenandoahCompareAndExchangeN: { 1169 Node *adr = n->in(MemNode::Address); 1170 conn_graph->add_local_var_and_edge(n, PointsToNode::NoEscape, adr, NULL); 1171 // fallthrough 1172 } 1173 case Op_ShenandoahCompareAndSwapP: 1174 case Op_ShenandoahCompareAndSwapN: 1175 case Op_ShenandoahWeakCompareAndSwapP: 1176 case Op_ShenandoahWeakCompareAndSwapN: 1177 return conn_graph->add_final_edges_unsafe_access(n, opcode); 1178 case Op_ShenandoahEnqueueBarrier: 1179 conn_graph->add_local_var_and_edge(n, PointsToNode::NoEscape, n->in(1), NULL); 1180 return true; 1181 case Op_ShenandoahLoadReferenceBarrier: 1182 conn_graph->add_local_var_and_edge(n, PointsToNode::NoEscape, n->in(ShenandoahLoadReferenceBarrierNode::ValueIn), NULL); 1183 return true; 1184 default: 1185 // Nothing 1186 break; 1187 } 1188 return false; 1189 } 1190 1191 bool ShenandoahBarrierSetC2::escape_has_out_with_unsafe_object(Node* n) const { 1192 return n->has_out_with(Op_ShenandoahCompareAndExchangeP) || n->has_out_with(Op_ShenandoahCompareAndExchangeN) || 1193 n->has_out_with(Op_ShenandoahCompareAndSwapP, Op_ShenandoahCompareAndSwapN, Op_ShenandoahWeakCompareAndSwapP, Op_ShenandoahWeakCompareAndSwapN); 1194 1195 } 1196 1197 bool ShenandoahBarrierSetC2::matcher_find_shared_post_visit(Matcher* matcher, Node* n, uint opcode) const { 1198 switch (opcode) { 1199 case Op_ShenandoahCompareAndExchangeP: 1200 case Op_ShenandoahCompareAndExchangeN: 1201 case Op_ShenandoahWeakCompareAndSwapP: 1202 case Op_ShenandoahWeakCompareAndSwapN: 1203 case Op_ShenandoahCompareAndSwapP: 1204 case Op_ShenandoahCompareAndSwapN: { // Convert trinary to binary-tree 1205 Node* newval = n->in(MemNode::ValueIn); 1206 Node* oldval = n->in(LoadStoreConditionalNode::ExpectedIn); 1207 Node* pair = new BinaryNode(oldval, newval); 1208 n->set_req(MemNode::ValueIn,pair); 1209 n->del_req(LoadStoreConditionalNode::ExpectedIn); 1210 return true; 1211 } 1212 default: 1213 break; 1214 } 1215 return false; 1216 } 1217 1218 bool ShenandoahBarrierSetC2::matcher_is_store_load_barrier(Node* x, uint xop) const { 1219 return xop == Op_ShenandoahCompareAndExchangeP || 1220 xop == Op_ShenandoahCompareAndExchangeN || 1221 xop == Op_ShenandoahWeakCompareAndSwapP || 1222 xop == Op_ShenandoahWeakCompareAndSwapN || 1223 xop == Op_ShenandoahCompareAndSwapN || 1224 xop == Op_ShenandoahCompareAndSwapP; 1225 }