1 /* 2 * Copyright (c) 2005, 2023, Oracle and/or its affiliates. All rights reserved. 3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. 4 * 5 * This code is free software; you can redistribute it and/or modify it 6 * under the terms of the GNU General Public License version 2 only, as 7 * published by the Free Software Foundation. 8 * 9 * This code is distributed in the hope that it will be useful, but WITHOUT 10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 12 * version 2 for more details (a copy is included in the LICENSE file that 13 * accompanied this code). 14 * 15 * You should have received a copy of the GNU General Public License version 16 * 2 along with this work; if not, write to the Free Software Foundation, 17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. 18 * 19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA 20 * or visit www.oracle.com if you need additional information or have any 21 * questions. 22 * 23 */ 24 25 #include "precompiled.hpp" 26 #include "compiler/compileLog.hpp" 27 #include "gc/shared/collectedHeap.inline.hpp" 28 #include "gc/shared/tlab_globals.hpp" 29 #include "libadt/vectset.hpp" 30 #include "memory/universe.hpp" 31 #include "opto/addnode.hpp" 32 #include "opto/arraycopynode.hpp" 33 #include "opto/callnode.hpp" 34 #include "opto/castnode.hpp" 35 #include "opto/cfgnode.hpp" 36 #include "opto/compile.hpp" 37 #include "opto/convertnode.hpp" 38 #include "opto/graphKit.hpp" 39 #include "opto/intrinsicnode.hpp" 40 #include "opto/locknode.hpp" 41 #include "opto/loopnode.hpp" 42 #include "opto/macro.hpp" 43 #include "opto/memnode.hpp" 44 #include "opto/narrowptrnode.hpp" 45 #include "opto/node.hpp" 46 #include "opto/opaquenode.hpp" 47 #include "opto/phaseX.hpp" 48 #include "opto/rootnode.hpp" 49 #include "opto/runtime.hpp" 50 #include "opto/subnode.hpp" 51 #include "opto/subtypenode.hpp" 52 #include "opto/type.hpp" 53 #include "prims/jvmtiExport.hpp" 54 #include "runtime/sharedRuntime.hpp" 55 #include "utilities/macros.hpp" 56 #include "utilities/powerOfTwo.hpp" 57 #if INCLUDE_G1GC 58 #include "gc/g1/g1ThreadLocalData.hpp" 59 #endif // INCLUDE_G1GC 60 61 62 // 63 // Replace any references to "oldref" in inputs to "use" with "newref". 64 // Returns the number of replacements made. 65 // 66 int PhaseMacroExpand::replace_input(Node *use, Node *oldref, Node *newref) { 67 int nreplacements = 0; 68 uint req = use->req(); 69 for (uint j = 0; j < use->len(); j++) { 70 Node *uin = use->in(j); 71 if (uin == oldref) { 72 if (j < req) 73 use->set_req(j, newref); 74 else 75 use->set_prec(j, newref); 76 nreplacements++; 77 } else if (j >= req && uin == nullptr) { 78 break; 79 } 80 } 81 return nreplacements; 82 } 83 84 void PhaseMacroExpand::migrate_outs(Node *old, Node *target) { 85 assert(old != nullptr, "sanity"); 86 for (DUIterator_Fast imax, i = old->fast_outs(imax); i < imax; i++) { 87 Node* use = old->fast_out(i); 88 _igvn.rehash_node_delayed(use); 89 imax -= replace_input(use, old, target); 90 // back up iterator 91 --i; 92 } 93 assert(old->outcnt() == 0, "all uses must be deleted"); 94 } 95 96 Node* PhaseMacroExpand::opt_bits_test(Node* ctrl, Node* region, int edge, Node* word, int mask, int bits, bool return_fast_path) { 97 Node* cmp; 98 if (mask != 0) { 99 Node* and_node = transform_later(new AndXNode(word, MakeConX(mask))); 100 cmp = transform_later(new CmpXNode(and_node, MakeConX(bits))); 101 } else { 102 cmp = word; 103 } 104 Node* bol = transform_later(new BoolNode(cmp, BoolTest::ne)); 105 IfNode* iff = new IfNode( ctrl, bol, PROB_MIN, COUNT_UNKNOWN ); 106 transform_later(iff); 107 108 // Fast path taken. 109 Node *fast_taken = transform_later(new IfFalseNode(iff)); 110 111 // Fast path not-taken, i.e. slow path 112 Node *slow_taken = transform_later(new IfTrueNode(iff)); 113 114 if (return_fast_path) { 115 region->init_req(edge, slow_taken); // Capture slow-control 116 return fast_taken; 117 } else { 118 region->init_req(edge, fast_taken); // Capture fast-control 119 return slow_taken; 120 } 121 } 122 123 //--------------------copy_predefined_input_for_runtime_call-------------------- 124 void PhaseMacroExpand::copy_predefined_input_for_runtime_call(Node * ctrl, CallNode* oldcall, CallNode* call) { 125 // Set fixed predefined input arguments 126 call->init_req( TypeFunc::Control, ctrl ); 127 call->init_req( TypeFunc::I_O , oldcall->in( TypeFunc::I_O) ); 128 call->init_req( TypeFunc::Memory , oldcall->in( TypeFunc::Memory ) ); // ????? 129 call->init_req( TypeFunc::ReturnAdr, oldcall->in( TypeFunc::ReturnAdr ) ); 130 call->init_req( TypeFunc::FramePtr, oldcall->in( TypeFunc::FramePtr ) ); 131 } 132 133 //------------------------------make_slow_call--------------------------------- 134 CallNode* PhaseMacroExpand::make_slow_call(CallNode *oldcall, const TypeFunc* slow_call_type, 135 address slow_call, const char* leaf_name, Node* slow_path, 136 Node* parm0, Node* parm1, Node* parm2) { 137 138 // Slow-path call 139 CallNode *call = leaf_name 140 ? (CallNode*)new CallLeafNode ( slow_call_type, slow_call, leaf_name, TypeRawPtr::BOTTOM ) 141 : (CallNode*)new CallStaticJavaNode( slow_call_type, slow_call, OptoRuntime::stub_name(slow_call), TypeRawPtr::BOTTOM ); 142 143 // Slow path call has no side-effects, uses few values 144 copy_predefined_input_for_runtime_call(slow_path, oldcall, call ); 145 if (parm0 != nullptr) call->init_req(TypeFunc::Parms+0, parm0); 146 if (parm1 != nullptr) call->init_req(TypeFunc::Parms+1, parm1); 147 if (parm2 != nullptr) call->init_req(TypeFunc::Parms+2, parm2); 148 call->copy_call_debug_info(&_igvn, oldcall); 149 call->set_cnt(PROB_UNLIKELY_MAG(4)); // Same effect as RC_UNCOMMON. 150 _igvn.replace_node(oldcall, call); 151 transform_later(call); 152 153 return call; 154 } 155 156 void PhaseMacroExpand::eliminate_gc_barrier(Node* p2x) { 157 BarrierSetC2 *bs = BarrierSet::barrier_set()->barrier_set_c2(); 158 bs->eliminate_gc_barrier(this, p2x); 159 } 160 161 // Search for a memory operation for the specified memory slice. 162 static Node *scan_mem_chain(Node *mem, int alias_idx, int offset, Node *start_mem, Node *alloc, PhaseGVN *phase) { 163 Node *orig_mem = mem; 164 Node *alloc_mem = alloc->in(TypeFunc::Memory); 165 const TypeOopPtr *tinst = phase->C->get_adr_type(alias_idx)->isa_oopptr(); 166 while (true) { 167 if (mem == alloc_mem || mem == start_mem ) { 168 return mem; // hit one of our sentinels 169 } else if (mem->is_MergeMem()) { 170 mem = mem->as_MergeMem()->memory_at(alias_idx); 171 } else if (mem->is_Proj() && mem->as_Proj()->_con == TypeFunc::Memory) { 172 Node *in = mem->in(0); 173 // we can safely skip over safepoints, calls, locks and membars because we 174 // already know that the object is safe to eliminate. 175 if (in->is_Initialize() && in->as_Initialize()->allocation() == alloc) { 176 return in; 177 } else if (in->is_Call()) { 178 CallNode *call = in->as_Call(); 179 if (call->may_modify(tinst, phase)) { 180 assert(call->is_ArrayCopy(), "ArrayCopy is the only call node that doesn't make allocation escape"); 181 if (call->as_ArrayCopy()->modifies(offset, offset, phase, false)) { 182 return in; 183 } 184 } 185 mem = in->in(TypeFunc::Memory); 186 } else if (in->is_MemBar()) { 187 ArrayCopyNode* ac = nullptr; 188 if (ArrayCopyNode::may_modify(tinst, in->as_MemBar(), phase, ac)) { 189 if (ac != nullptr) { 190 assert(ac->is_clonebasic(), "Only basic clone is a non escaping clone"); 191 return ac; 192 } 193 } 194 mem = in->in(TypeFunc::Memory); 195 } else { 196 #ifdef ASSERT 197 in->dump(); 198 mem->dump(); 199 assert(false, "unexpected projection"); 200 #endif 201 } 202 } else if (mem->is_Store()) { 203 const TypePtr* atype = mem->as_Store()->adr_type(); 204 int adr_idx = phase->C->get_alias_index(atype); 205 if (adr_idx == alias_idx) { 206 assert(atype->isa_oopptr(), "address type must be oopptr"); 207 int adr_offset = atype->offset(); 208 uint adr_iid = atype->is_oopptr()->instance_id(); 209 // Array elements references have the same alias_idx 210 // but different offset and different instance_id. 211 if (adr_offset == offset && adr_iid == alloc->_idx) { 212 return mem; 213 } 214 } else { 215 assert(adr_idx == Compile::AliasIdxRaw, "address must match or be raw"); 216 } 217 mem = mem->in(MemNode::Memory); 218 } else if (mem->is_ClearArray()) { 219 if (!ClearArrayNode::step_through(&mem, alloc->_idx, phase)) { 220 // Can not bypass initialization of the instance 221 // we are looking. 222 debug_only(intptr_t offset;) 223 assert(alloc == AllocateNode::Ideal_allocation(mem->in(3), phase, offset), "sanity"); 224 InitializeNode* init = alloc->as_Allocate()->initialization(); 225 // We are looking for stored value, return Initialize node 226 // or memory edge from Allocate node. 227 if (init != nullptr) { 228 return init; 229 } else { 230 return alloc->in(TypeFunc::Memory); // It will produce zero value (see callers). 231 } 232 } 233 // Otherwise skip it (the call updated 'mem' value). 234 } else if (mem->Opcode() == Op_SCMemProj) { 235 mem = mem->in(0); 236 Node* adr = nullptr; 237 if (mem->is_LoadStore()) { 238 adr = mem->in(MemNode::Address); 239 } else { 240 assert(mem->Opcode() == Op_EncodeISOArray || 241 mem->Opcode() == Op_StrCompressedCopy, "sanity"); 242 adr = mem->in(3); // Destination array 243 } 244 const TypePtr* atype = adr->bottom_type()->is_ptr(); 245 int adr_idx = phase->C->get_alias_index(atype); 246 if (adr_idx == alias_idx) { 247 DEBUG_ONLY(mem->dump();) 248 assert(false, "Object is not scalar replaceable if a LoadStore node accesses its field"); 249 return nullptr; 250 } 251 mem = mem->in(MemNode::Memory); 252 } else if (mem->Opcode() == Op_StrInflatedCopy) { 253 Node* adr = mem->in(3); // Destination array 254 const TypePtr* atype = adr->bottom_type()->is_ptr(); 255 int adr_idx = phase->C->get_alias_index(atype); 256 if (adr_idx == alias_idx) { 257 DEBUG_ONLY(mem->dump();) 258 assert(false, "Object is not scalar replaceable if a StrInflatedCopy node accesses its field"); 259 return nullptr; 260 } 261 mem = mem->in(MemNode::Memory); 262 } else { 263 return mem; 264 } 265 assert(mem != orig_mem, "dead memory loop"); 266 } 267 } 268 269 // Generate loads from source of the arraycopy for fields of 270 // destination needed at a deoptimization point 271 Node* PhaseMacroExpand::make_arraycopy_load(ArrayCopyNode* ac, intptr_t offset, Node* ctl, Node* mem, BasicType ft, const Type *ftype, AllocateNode *alloc) { 272 BasicType bt = ft; 273 const Type *type = ftype; 274 if (ft == T_NARROWOOP) { 275 bt = T_OBJECT; 276 type = ftype->make_oopptr(); 277 } 278 Node* res = nullptr; 279 if (ac->is_clonebasic()) { 280 assert(ac->in(ArrayCopyNode::Src) != ac->in(ArrayCopyNode::Dest), "clone source equals destination"); 281 Node* base = ac->in(ArrayCopyNode::Src); 282 Node* adr = _igvn.transform(new AddPNode(base, base, MakeConX(offset))); 283 const TypePtr* adr_type = _igvn.type(base)->is_ptr()->add_offset(offset); 284 MergeMemNode* mergemen = _igvn.transform(MergeMemNode::make(mem))->as_MergeMem(); 285 BarrierSetC2* bs = BarrierSet::barrier_set()->barrier_set_c2(); 286 res = ArrayCopyNode::load(bs, &_igvn, ctl, mergemen, adr, adr_type, type, bt); 287 } else { 288 if (ac->modifies(offset, offset, &_igvn, true)) { 289 assert(ac->in(ArrayCopyNode::Dest) == alloc->result_cast(), "arraycopy destination should be allocation's result"); 290 uint shift = exact_log2(type2aelembytes(bt)); 291 Node* src_pos = ac->in(ArrayCopyNode::SrcPos); 292 Node* dest_pos = ac->in(ArrayCopyNode::DestPos); 293 const TypeInt* src_pos_t = _igvn.type(src_pos)->is_int(); 294 const TypeInt* dest_pos_t = _igvn.type(dest_pos)->is_int(); 295 296 Node* adr = nullptr; 297 const TypePtr* adr_type = nullptr; 298 if (src_pos_t->is_con() && dest_pos_t->is_con()) { 299 intptr_t off = ((src_pos_t->get_con() - dest_pos_t->get_con()) << shift) + offset; 300 Node* base = ac->in(ArrayCopyNode::Src); 301 adr = _igvn.transform(new AddPNode(base, base, MakeConX(off))); 302 adr_type = _igvn.type(base)->is_ptr()->add_offset(off); 303 if (ac->in(ArrayCopyNode::Src) == ac->in(ArrayCopyNode::Dest)) { 304 // Don't emit a new load from src if src == dst but try to get the value from memory instead 305 return value_from_mem(ac->in(TypeFunc::Memory), ctl, ft, ftype, adr_type->isa_oopptr(), alloc); 306 } 307 } else { 308 Node* diff = _igvn.transform(new SubINode(ac->in(ArrayCopyNode::SrcPos), ac->in(ArrayCopyNode::DestPos))); 309 #ifdef _LP64 310 diff = _igvn.transform(new ConvI2LNode(diff)); 311 #endif 312 diff = _igvn.transform(new LShiftXNode(diff, intcon(shift))); 313 314 Node* off = _igvn.transform(new AddXNode(MakeConX(offset), diff)); 315 Node* base = ac->in(ArrayCopyNode::Src); 316 adr = _igvn.transform(new AddPNode(base, base, off)); 317 adr_type = _igvn.type(base)->is_ptr()->add_offset(Type::OffsetBot); 318 if (ac->in(ArrayCopyNode::Src) == ac->in(ArrayCopyNode::Dest)) { 319 // Non constant offset in the array: we can't statically 320 // determine the value 321 return nullptr; 322 } 323 } 324 MergeMemNode* mergemen = _igvn.transform(MergeMemNode::make(mem))->as_MergeMem(); 325 BarrierSetC2* bs = BarrierSet::barrier_set()->barrier_set_c2(); 326 res = ArrayCopyNode::load(bs, &_igvn, ctl, mergemen, adr, adr_type, type, bt); 327 } 328 } 329 if (res != nullptr) { 330 if (ftype->isa_narrowoop()) { 331 // PhaseMacroExpand::scalar_replacement adds DecodeN nodes 332 res = _igvn.transform(new EncodePNode(res, ftype)); 333 } 334 return res; 335 } 336 return nullptr; 337 } 338 339 // 340 // Given a Memory Phi, compute a value Phi containing the values from stores 341 // on the input paths. 342 // Note: this function is recursive, its depth is limited by the "level" argument 343 // Returns the computed Phi, or null if it cannot compute it. 344 Node *PhaseMacroExpand::value_from_mem_phi(Node *mem, BasicType ft, const Type *phi_type, const TypeOopPtr *adr_t, AllocateNode *alloc, Node_Stack *value_phis, int level) { 345 assert(mem->is_Phi(), "sanity"); 346 int alias_idx = C->get_alias_index(adr_t); 347 int offset = adr_t->offset(); 348 int instance_id = adr_t->instance_id(); 349 350 // Check if an appropriate value phi already exists. 351 Node* region = mem->in(0); 352 for (DUIterator_Fast kmax, k = region->fast_outs(kmax); k < kmax; k++) { 353 Node* phi = region->fast_out(k); 354 if (phi->is_Phi() && phi != mem && 355 phi->as_Phi()->is_same_inst_field(phi_type, (int)mem->_idx, instance_id, alias_idx, offset)) { 356 return phi; 357 } 358 } 359 // Check if an appropriate new value phi already exists. 360 Node* new_phi = value_phis->find(mem->_idx); 361 if (new_phi != nullptr) 362 return new_phi; 363 364 if (level <= 0) { 365 return nullptr; // Give up: phi tree too deep 366 } 367 Node *start_mem = C->start()->proj_out_or_null(TypeFunc::Memory); 368 Node *alloc_mem = alloc->in(TypeFunc::Memory); 369 370 uint length = mem->req(); 371 GrowableArray <Node *> values(length, length, nullptr); 372 373 // create a new Phi for the value 374 PhiNode *phi = new PhiNode(mem->in(0), phi_type, nullptr, mem->_idx, instance_id, alias_idx, offset); 375 transform_later(phi); 376 value_phis->push(phi, mem->_idx); 377 378 for (uint j = 1; j < length; j++) { 379 Node *in = mem->in(j); 380 if (in == nullptr || in->is_top()) { 381 values.at_put(j, in); 382 } else { 383 Node *val = scan_mem_chain(in, alias_idx, offset, start_mem, alloc, &_igvn); 384 if (val == start_mem || val == alloc_mem) { 385 // hit a sentinel, return appropriate 0 value 386 values.at_put(j, _igvn.zerocon(ft)); 387 continue; 388 } 389 if (val->is_Initialize()) { 390 val = val->as_Initialize()->find_captured_store(offset, type2aelembytes(ft), &_igvn); 391 } 392 if (val == nullptr) { 393 return nullptr; // can't find a value on this path 394 } 395 if (val == mem) { 396 values.at_put(j, mem); 397 } else if (val->is_Store()) { 398 Node* n = val->in(MemNode::ValueIn); 399 BarrierSetC2* bs = BarrierSet::barrier_set()->barrier_set_c2(); 400 n = bs->step_over_gc_barrier(n); 401 if (is_subword_type(ft)) { 402 n = Compile::narrow_value(ft, n, phi_type, &_igvn, true); 403 } 404 values.at_put(j, n); 405 } else if(val->is_Proj() && val->in(0) == alloc) { 406 values.at_put(j, _igvn.zerocon(ft)); 407 } else if (val->is_Phi()) { 408 val = value_from_mem_phi(val, ft, phi_type, adr_t, alloc, value_phis, level-1); 409 if (val == nullptr) { 410 return nullptr; 411 } 412 values.at_put(j, val); 413 } else if (val->Opcode() == Op_SCMemProj) { 414 assert(val->in(0)->is_LoadStore() || 415 val->in(0)->Opcode() == Op_EncodeISOArray || 416 val->in(0)->Opcode() == Op_StrCompressedCopy, "sanity"); 417 assert(false, "Object is not scalar replaceable if a LoadStore node accesses its field"); 418 return nullptr; 419 } else if (val->is_ArrayCopy()) { 420 Node* res = make_arraycopy_load(val->as_ArrayCopy(), offset, val->in(0), val->in(TypeFunc::Memory), ft, phi_type, alloc); 421 if (res == nullptr) { 422 return nullptr; 423 } 424 values.at_put(j, res); 425 } else { 426 DEBUG_ONLY( val->dump(); ) 427 assert(false, "unknown node on this path"); 428 return nullptr; // unknown node on this path 429 } 430 } 431 } 432 // Set Phi's inputs 433 for (uint j = 1; j < length; j++) { 434 if (values.at(j) == mem) { 435 phi->init_req(j, phi); 436 } else { 437 phi->init_req(j, values.at(j)); 438 } 439 } 440 return phi; 441 } 442 443 // Search the last value stored into the object's field. 444 Node *PhaseMacroExpand::value_from_mem(Node *sfpt_mem, Node *sfpt_ctl, BasicType ft, const Type *ftype, const TypeOopPtr *adr_t, AllocateNode *alloc) { 445 assert(adr_t->is_known_instance_field(), "instance required"); 446 int instance_id = adr_t->instance_id(); 447 assert((uint)instance_id == alloc->_idx, "wrong allocation"); 448 449 int alias_idx = C->get_alias_index(adr_t); 450 int offset = adr_t->offset(); 451 Node *start_mem = C->start()->proj_out_or_null(TypeFunc::Memory); 452 Node *alloc_ctrl = alloc->in(TypeFunc::Control); 453 Node *alloc_mem = alloc->in(TypeFunc::Memory); 454 VectorSet visited; 455 456 bool done = sfpt_mem == alloc_mem; 457 Node *mem = sfpt_mem; 458 while (!done) { 459 if (visited.test_set(mem->_idx)) { 460 return nullptr; // found a loop, give up 461 } 462 mem = scan_mem_chain(mem, alias_idx, offset, start_mem, alloc, &_igvn); 463 if (mem == start_mem || mem == alloc_mem) { 464 done = true; // hit a sentinel, return appropriate 0 value 465 } else if (mem->is_Initialize()) { 466 mem = mem->as_Initialize()->find_captured_store(offset, type2aelembytes(ft), &_igvn); 467 if (mem == nullptr) { 468 done = true; // Something go wrong. 469 } else if (mem->is_Store()) { 470 const TypePtr* atype = mem->as_Store()->adr_type(); 471 assert(C->get_alias_index(atype) == Compile::AliasIdxRaw, "store is correct memory slice"); 472 done = true; 473 } 474 } else if (mem->is_Store()) { 475 const TypeOopPtr* atype = mem->as_Store()->adr_type()->isa_oopptr(); 476 assert(atype != nullptr, "address type must be oopptr"); 477 assert(C->get_alias_index(atype) == alias_idx && 478 atype->is_known_instance_field() && atype->offset() == offset && 479 atype->instance_id() == instance_id, "store is correct memory slice"); 480 done = true; 481 } else if (mem->is_Phi()) { 482 // try to find a phi's unique input 483 Node *unique_input = nullptr; 484 Node *top = C->top(); 485 for (uint i = 1; i < mem->req(); i++) { 486 Node *n = scan_mem_chain(mem->in(i), alias_idx, offset, start_mem, alloc, &_igvn); 487 if (n == nullptr || n == top || n == mem) { 488 continue; 489 } else if (unique_input == nullptr) { 490 unique_input = n; 491 } else if (unique_input != n) { 492 unique_input = top; 493 break; 494 } 495 } 496 if (unique_input != nullptr && unique_input != top) { 497 mem = unique_input; 498 } else { 499 done = true; 500 } 501 } else if (mem->is_ArrayCopy()) { 502 done = true; 503 } else { 504 DEBUG_ONLY( mem->dump(); ) 505 assert(false, "unexpected node"); 506 } 507 } 508 if (mem != nullptr) { 509 if (mem == start_mem || mem == alloc_mem) { 510 // hit a sentinel, return appropriate 0 value 511 return _igvn.zerocon(ft); 512 } else if (mem->is_Store()) { 513 Node* n = mem->in(MemNode::ValueIn); 514 BarrierSetC2* bs = BarrierSet::barrier_set()->barrier_set_c2(); 515 n = bs->step_over_gc_barrier(n); 516 return n; 517 } else if (mem->is_Phi()) { 518 // attempt to produce a Phi reflecting the values on the input paths of the Phi 519 Node_Stack value_phis(8); 520 Node* phi = value_from_mem_phi(mem, ft, ftype, adr_t, alloc, &value_phis, ValueSearchLimit); 521 if (phi != nullptr) { 522 return phi; 523 } else { 524 // Kill all new Phis 525 while(value_phis.is_nonempty()) { 526 Node* n = value_phis.node(); 527 _igvn.replace_node(n, C->top()); 528 value_phis.pop(); 529 } 530 } 531 } else if (mem->is_ArrayCopy()) { 532 Node* ctl = mem->in(0); 533 Node* m = mem->in(TypeFunc::Memory); 534 if (sfpt_ctl->is_Proj() && sfpt_ctl->as_Proj()->is_uncommon_trap_proj(Deoptimization::Reason_none)) { 535 // pin the loads in the uncommon trap path 536 ctl = sfpt_ctl; 537 m = sfpt_mem; 538 } 539 return make_arraycopy_load(mem->as_ArrayCopy(), offset, ctl, m, ft, ftype, alloc); 540 } 541 } 542 // Something go wrong. 543 return nullptr; 544 } 545 546 // Check the possibility of scalar replacement. 547 bool PhaseMacroExpand::can_eliminate_allocation(AllocateNode *alloc, GrowableArray <SafePointNode *>& safepoints) { 548 // Scan the uses of the allocation to check for anything that would 549 // prevent us from eliminating it. 550 NOT_PRODUCT( const char* fail_eliminate = nullptr; ) 551 DEBUG_ONLY( Node* disq_node = nullptr; ) 552 bool can_eliminate = true; 553 554 Node* res = alloc->result_cast(); 555 const TypeOopPtr* res_type = nullptr; 556 if (res == nullptr) { 557 // All users were eliminated. 558 } else if (!res->is_CheckCastPP()) { 559 NOT_PRODUCT(fail_eliminate = "Allocation does not have unique CheckCastPP";) 560 can_eliminate = false; 561 } else { 562 res_type = _igvn.type(res)->isa_oopptr(); 563 if (res_type == nullptr) { 564 NOT_PRODUCT(fail_eliminate = "Neither instance or array allocation";) 565 can_eliminate = false; 566 } else if (res_type->isa_aryptr()) { 567 int length = alloc->in(AllocateNode::ALength)->find_int_con(-1); 568 if (length < 0) { 569 NOT_PRODUCT(fail_eliminate = "Array's size is not constant";) 570 can_eliminate = false; 571 } 572 } 573 } 574 575 if (can_eliminate && res != nullptr) { 576 BarrierSetC2 *bs = BarrierSet::barrier_set()->barrier_set_c2(); 577 for (DUIterator_Fast jmax, j = res->fast_outs(jmax); 578 j < jmax && can_eliminate; j++) { 579 Node* use = res->fast_out(j); 580 581 if (use->is_AddP()) { 582 const TypePtr* addp_type = _igvn.type(use)->is_ptr(); 583 int offset = addp_type->offset(); 584 585 if (offset == Type::OffsetTop || offset == Type::OffsetBot) { 586 NOT_PRODUCT(fail_eliminate = "Undefined field referrence";) 587 can_eliminate = false; 588 break; 589 } 590 for (DUIterator_Fast kmax, k = use->fast_outs(kmax); 591 k < kmax && can_eliminate; k++) { 592 Node* n = use->fast_out(k); 593 if (!n->is_Store() && n->Opcode() != Op_CastP2X && !bs->is_gc_pre_barrier_node(n)) { 594 DEBUG_ONLY(disq_node = n;) 595 if (n->is_Load() || n->is_LoadStore()) { 596 NOT_PRODUCT(fail_eliminate = "Field load";) 597 } else { 598 NOT_PRODUCT(fail_eliminate = "Not store field referrence";) 599 } 600 can_eliminate = false; 601 } 602 } 603 } else if (use->is_ArrayCopy() && 604 (use->as_ArrayCopy()->is_clonebasic() || 605 use->as_ArrayCopy()->is_arraycopy_validated() || 606 use->as_ArrayCopy()->is_copyof_validated() || 607 use->as_ArrayCopy()->is_copyofrange_validated()) && 608 use->in(ArrayCopyNode::Dest) == res) { 609 // ok to eliminate 610 } else if (use->is_SafePoint()) { 611 SafePointNode* sfpt = use->as_SafePoint(); 612 if (sfpt->is_Call() && sfpt->as_Call()->has_non_debug_use(res)) { 613 // Object is passed as argument. 614 DEBUG_ONLY(disq_node = use;) 615 NOT_PRODUCT(fail_eliminate = "Object is passed as argument";) 616 can_eliminate = false; 617 } 618 Node* sfptMem = sfpt->memory(); 619 if (sfptMem == nullptr || sfptMem->is_top()) { 620 DEBUG_ONLY(disq_node = use;) 621 NOT_PRODUCT(fail_eliminate = "null or TOP memory";) 622 can_eliminate = false; 623 } else { 624 safepoints.append_if_missing(sfpt); 625 } 626 } else if (use->Opcode() != Op_CastP2X) { // CastP2X is used by card mark 627 if (use->is_Phi()) { 628 if (use->outcnt() == 1 && use->unique_out()->Opcode() == Op_Return) { 629 NOT_PRODUCT(fail_eliminate = "Object is return value";) 630 } else { 631 NOT_PRODUCT(fail_eliminate = "Object is referenced by Phi";) 632 } 633 DEBUG_ONLY(disq_node = use;) 634 } else { 635 if (use->Opcode() == Op_Return) { 636 NOT_PRODUCT(fail_eliminate = "Object is return value";) 637 }else { 638 NOT_PRODUCT(fail_eliminate = "Object is referenced by node";) 639 } 640 DEBUG_ONLY(disq_node = use;) 641 } 642 can_eliminate = false; 643 } 644 } 645 } 646 647 #ifndef PRODUCT 648 if (PrintEliminateAllocations) { 649 if (can_eliminate) { 650 tty->print("Scalar "); 651 if (res == nullptr) 652 alloc->dump(); 653 else 654 res->dump(); 655 } else if (alloc->_is_scalar_replaceable) { 656 tty->print("NotScalar (%s)", fail_eliminate); 657 if (res == nullptr) 658 alloc->dump(); 659 else 660 res->dump(); 661 #ifdef ASSERT 662 if (disq_node != nullptr) { 663 tty->print(" >>>> "); 664 disq_node->dump(); 665 } 666 #endif /*ASSERT*/ 667 } 668 } 669 #endif 670 return can_eliminate; 671 } 672 673 // Do scalar replacement. 674 bool PhaseMacroExpand::scalar_replacement(AllocateNode *alloc, GrowableArray <SafePointNode *>& safepoints) { 675 GrowableArray <SafePointNode *> safepoints_done; 676 677 ciKlass* klass = NULL; 678 ciInstanceKlass* iklass = nullptr; 679 int nfields = 0; 680 int array_base = 0; 681 int element_size = 0; 682 BasicType basic_elem_type = T_ILLEGAL; 683 ciType* elem_type = nullptr; 684 685 Node* res = alloc->result_cast(); 686 assert(res == nullptr || res->is_CheckCastPP(), "unexpected AllocateNode result"); 687 const TypeOopPtr* res_type = nullptr; 688 if (res != nullptr) { // Could be null when there are no users 689 res_type = _igvn.type(res)->isa_oopptr(); 690 } 691 692 if (res != nullptr) { 693 klass = res_type->klass(); 694 if (res_type->isa_instptr()) { 695 // find the fields of the class which will be needed for safepoint debug information 696 assert(klass->is_instance_klass(), "must be an instance klass."); 697 iklass = klass->as_instance_klass(); 698 nfields = iklass->nof_nonstatic_fields(); 699 } else { 700 // find the array's elements which will be needed for safepoint debug information 701 nfields = alloc->in(AllocateNode::ALength)->find_int_con(-1); 702 assert(klass->is_array_klass() && nfields >= 0, "must be an array klass."); 703 elem_type = klass->as_array_klass()->element_type(); 704 basic_elem_type = elem_type->basic_type(); 705 array_base = arrayOopDesc::base_offset_in_bytes(basic_elem_type); 706 element_size = type2aelembytes(basic_elem_type); 707 } 708 } 709 // 710 // Process the safepoint uses 711 // 712 while (safepoints.length() > 0) { 713 SafePointNode* sfpt = safepoints.pop(); 714 Node* mem = sfpt->memory(); 715 Node* ctl = sfpt->control(); 716 assert(sfpt->jvms() != nullptr, "missed JVMS"); 717 // Fields of scalar objs are referenced only at the end 718 // of regular debuginfo at the last (youngest) JVMS. 719 // Record relative start index. 720 uint first_ind = (sfpt->req() - sfpt->jvms()->scloff()); 721 SafePointScalarObjectNode* sobj = new SafePointScalarObjectNode(res_type, 722 #ifdef ASSERT 723 alloc, 724 #endif 725 first_ind, nfields); 726 sobj->init_req(0, C->root()); 727 transform_later(sobj); 728 729 // Scan object's fields adding an input to the safepoint for each field. 730 for (int j = 0; j < nfields; j++) { 731 intptr_t offset; 732 ciField* field = nullptr; 733 if (iklass != nullptr) { 734 field = iklass->nonstatic_field_at(j); 735 offset = field->offset(); 736 elem_type = field->type(); 737 basic_elem_type = field->layout_type(); 738 } else { 739 offset = array_base + j * (intptr_t)element_size; 740 } 741 742 const Type *field_type; 743 // The next code is taken from Parse::do_get_xxx(). 744 if (is_reference_type(basic_elem_type)) { 745 if (!elem_type->is_loaded()) { 746 field_type = TypeInstPtr::BOTTOM; 747 } else if (field != nullptr && field->is_static_constant()) { 748 // This can happen if the constant oop is non-perm. 749 ciObject* con = field->constant_value().as_object(); 750 // Do not "join" in the previous type; it doesn't add value, 751 // and may yield a vacuous result if the field is of interface type. 752 field_type = TypeOopPtr::make_from_constant(con)->isa_oopptr(); 753 assert(field_type != nullptr, "field singleton type must be consistent"); 754 } else { 755 field_type = TypeOopPtr::make_from_klass(elem_type->as_klass()); 756 } 757 if (UseCompressedOops) { 758 field_type = field_type->make_narrowoop(); 759 basic_elem_type = T_NARROWOOP; 760 } 761 } else { 762 field_type = Type::get_const_basic_type(basic_elem_type); 763 } 764 765 const TypeOopPtr *field_addr_type = res_type->add_offset(offset)->isa_oopptr(); 766 767 Node *field_val = value_from_mem(mem, ctl, basic_elem_type, field_type, field_addr_type, alloc); 768 if (field_val == nullptr) { 769 // We weren't able to find a value for this field, 770 // give up on eliminating this allocation. 771 772 // Remove any extra entries we added to the safepoint. 773 uint last = sfpt->req() - 1; 774 for (int k = 0; k < j; k++) { 775 sfpt->del_req(last--); 776 } 777 _igvn._worklist.push(sfpt); 778 // rollback processed safepoints 779 while (safepoints_done.length() > 0) { 780 SafePointNode* sfpt_done = safepoints_done.pop(); 781 // remove any extra entries we added to the safepoint 782 last = sfpt_done->req() - 1; 783 for (int k = 0; k < nfields; k++) { 784 sfpt_done->del_req(last--); 785 } 786 JVMState *jvms = sfpt_done->jvms(); 787 jvms->set_endoff(sfpt_done->req()); 788 // Now make a pass over the debug information replacing any references 789 // to SafePointScalarObjectNode with the allocated object. 790 int start = jvms->debug_start(); 791 int end = jvms->debug_end(); 792 for (int i = start; i < end; i++) { 793 if (sfpt_done->in(i)->is_SafePointScalarObject()) { 794 SafePointScalarObjectNode* scobj = sfpt_done->in(i)->as_SafePointScalarObject(); 795 if (scobj->first_index(jvms) == sfpt_done->req() && 796 scobj->n_fields() == (uint)nfields) { 797 assert(scobj->alloc() == alloc, "sanity"); 798 sfpt_done->set_req(i, res); 799 } 800 } 801 } 802 _igvn._worklist.push(sfpt_done); 803 } 804 #ifndef PRODUCT 805 if (PrintEliminateAllocations) { 806 if (field != nullptr) { 807 tty->print("=== At SafePoint node %d can't find value of Field: ", 808 sfpt->_idx); 809 field->print(); 810 int field_idx = C->get_alias_index(field_addr_type); 811 tty->print(" (alias_idx=%d)", field_idx); 812 } else { // Array's element 813 tty->print("=== At SafePoint node %d can't find value of array element [%d]", 814 sfpt->_idx, j); 815 } 816 tty->print(", which prevents elimination of: "); 817 if (res == nullptr) 818 alloc->dump(); 819 else 820 res->dump(); 821 } 822 #endif 823 return false; 824 } 825 if (UseCompressedOops && field_type->isa_narrowoop()) { 826 // Enable "DecodeN(EncodeP(Allocate)) --> Allocate" transformation 827 // to be able scalar replace the allocation. 828 if (field_val->is_EncodeP()) { 829 field_val = field_val->in(1); 830 } else { 831 field_val = transform_later(new DecodeNNode(field_val, field_val->get_ptr_type())); 832 } 833 } 834 sfpt->add_req(field_val); 835 } 836 JVMState *jvms = sfpt->jvms(); 837 jvms->set_endoff(sfpt->req()); 838 // Now make a pass over the debug information replacing any references 839 // to the allocated object with "sobj" 840 int start = jvms->debug_start(); 841 int end = jvms->debug_end(); 842 sfpt->replace_edges_in_range(res, sobj, start, end, &_igvn); 843 _igvn._worklist.push(sfpt); 844 safepoints_done.append_if_missing(sfpt); // keep it for rollback 845 } 846 return true; 847 } 848 849 static void disconnect_projections(MultiNode* n, PhaseIterGVN& igvn) { 850 Node* ctl_proj = n->proj_out_or_null(TypeFunc::Control); 851 Node* mem_proj = n->proj_out_or_null(TypeFunc::Memory); 852 if (ctl_proj != nullptr) { 853 igvn.replace_node(ctl_proj, n->in(0)); 854 } 855 if (mem_proj != nullptr) { 856 igvn.replace_node(mem_proj, n->in(TypeFunc::Memory)); 857 } 858 } 859 860 // Process users of eliminated allocation. 861 void PhaseMacroExpand::process_users_of_allocation(CallNode *alloc) { 862 Node* res = alloc->result_cast(); 863 if (res != nullptr) { 864 for (DUIterator_Last jmin, j = res->last_outs(jmin); j >= jmin; ) { 865 Node *use = res->last_out(j); 866 uint oc1 = res->outcnt(); 867 868 if (use->is_AddP()) { 869 for (DUIterator_Last kmin, k = use->last_outs(kmin); k >= kmin; ) { 870 Node *n = use->last_out(k); 871 uint oc2 = use->outcnt(); 872 if (n->is_Store()) { 873 #ifdef ASSERT 874 // Verify that there is no dependent MemBarVolatile nodes, 875 // they should be removed during IGVN, see MemBarNode::Ideal(). 876 for (DUIterator_Fast pmax, p = n->fast_outs(pmax); 877 p < pmax; p++) { 878 Node* mb = n->fast_out(p); 879 assert(mb->is_Initialize() || !mb->is_MemBar() || 880 mb->req() <= MemBarNode::Precedent || 881 mb->in(MemBarNode::Precedent) != n, 882 "MemBarVolatile should be eliminated for non-escaping object"); 883 } 884 #endif 885 _igvn.replace_node(n, n->in(MemNode::Memory)); 886 } else { 887 eliminate_gc_barrier(n); 888 } 889 k -= (oc2 - use->outcnt()); 890 } 891 _igvn.remove_dead_node(use); 892 } else if (use->is_ArrayCopy()) { 893 // Disconnect ArrayCopy node 894 ArrayCopyNode* ac = use->as_ArrayCopy(); 895 if (ac->is_clonebasic()) { 896 Node* membar_after = ac->proj_out(TypeFunc::Control)->unique_ctrl_out(); 897 disconnect_projections(ac, _igvn); 898 assert(alloc->in(TypeFunc::Memory)->is_Proj() && alloc->in(TypeFunc::Memory)->in(0)->Opcode() == Op_MemBarCPUOrder, "mem barrier expected before allocation"); 899 Node* membar_before = alloc->in(TypeFunc::Memory)->in(0); 900 disconnect_projections(membar_before->as_MemBar(), _igvn); 901 if (membar_after->is_MemBar()) { 902 disconnect_projections(membar_after->as_MemBar(), _igvn); 903 } 904 } else { 905 assert(ac->is_arraycopy_validated() || 906 ac->is_copyof_validated() || 907 ac->is_copyofrange_validated(), "unsupported"); 908 CallProjections callprojs; 909 ac->extract_projections(&callprojs, true); 910 911 _igvn.replace_node(callprojs.fallthrough_ioproj, ac->in(TypeFunc::I_O)); 912 _igvn.replace_node(callprojs.fallthrough_memproj, ac->in(TypeFunc::Memory)); 913 _igvn.replace_node(callprojs.fallthrough_catchproj, ac->in(TypeFunc::Control)); 914 915 // Set control to top. IGVN will remove the remaining projections 916 ac->set_req(0, top()); 917 ac->replace_edge(res, top(), &_igvn); 918 919 // Disconnect src right away: it can help find new 920 // opportunities for allocation elimination 921 Node* src = ac->in(ArrayCopyNode::Src); 922 ac->replace_edge(src, top(), &_igvn); 923 // src can be top at this point if src and dest of the 924 // arraycopy were the same 925 if (src->outcnt() == 0 && !src->is_top()) { 926 _igvn.remove_dead_node(src); 927 } 928 } 929 _igvn._worklist.push(ac); 930 } else { 931 eliminate_gc_barrier(use); 932 } 933 j -= (oc1 - res->outcnt()); 934 } 935 assert(res->outcnt() == 0, "all uses of allocated objects must be deleted"); 936 _igvn.remove_dead_node(res); 937 } 938 939 // 940 // Process other users of allocation's projections 941 // 942 if (_callprojs.resproj != nullptr && _callprojs.resproj->outcnt() != 0) { 943 // First disconnect stores captured by Initialize node. 944 // If Initialize node is eliminated first in the following code, 945 // it will kill such stores and DUIterator_Last will assert. 946 for (DUIterator_Fast jmax, j = _callprojs.resproj->fast_outs(jmax); j < jmax; j++) { 947 Node* use = _callprojs.resproj->fast_out(j); 948 if (use->is_AddP()) { 949 // raw memory addresses used only by the initialization 950 _igvn.replace_node(use, C->top()); 951 --j; --jmax; 952 } 953 } 954 for (DUIterator_Last jmin, j = _callprojs.resproj->last_outs(jmin); j >= jmin; ) { 955 Node* use = _callprojs.resproj->last_out(j); 956 uint oc1 = _callprojs.resproj->outcnt(); 957 if (use->is_Initialize()) { 958 // Eliminate Initialize node. 959 InitializeNode *init = use->as_Initialize(); 960 assert(init->outcnt() <= 2, "only a control and memory projection expected"); 961 Node *ctrl_proj = init->proj_out_or_null(TypeFunc::Control); 962 if (ctrl_proj != nullptr) { 963 _igvn.replace_node(ctrl_proj, init->in(TypeFunc::Control)); 964 #ifdef ASSERT 965 // If the InitializeNode has no memory out, it will die, and tmp will become null 966 Node* tmp = init->in(TypeFunc::Control); 967 assert(tmp == nullptr || tmp == _callprojs.fallthrough_catchproj, "allocation control projection"); 968 #endif 969 } 970 Node *mem_proj = init->proj_out_or_null(TypeFunc::Memory); 971 if (mem_proj != nullptr) { 972 Node *mem = init->in(TypeFunc::Memory); 973 #ifdef ASSERT 974 if (mem->is_MergeMem()) { 975 assert(mem->in(TypeFunc::Memory) == _callprojs.fallthrough_memproj, "allocation memory projection"); 976 } else { 977 assert(mem == _callprojs.fallthrough_memproj, "allocation memory projection"); 978 } 979 #endif 980 _igvn.replace_node(mem_proj, mem); 981 } 982 } else { 983 assert(false, "only Initialize or AddP expected"); 984 } 985 j -= (oc1 - _callprojs.resproj->outcnt()); 986 } 987 } 988 if (_callprojs.fallthrough_catchproj != nullptr) { 989 _igvn.replace_node(_callprojs.fallthrough_catchproj, alloc->in(TypeFunc::Control)); 990 } 991 if (_callprojs.fallthrough_memproj != nullptr) { 992 _igvn.replace_node(_callprojs.fallthrough_memproj, alloc->in(TypeFunc::Memory)); 993 } 994 if (_callprojs.catchall_memproj != nullptr) { 995 _igvn.replace_node(_callprojs.catchall_memproj, C->top()); 996 } 997 if (_callprojs.fallthrough_ioproj != nullptr) { 998 _igvn.replace_node(_callprojs.fallthrough_ioproj, alloc->in(TypeFunc::I_O)); 999 } 1000 if (_callprojs.catchall_ioproj != nullptr) { 1001 _igvn.replace_node(_callprojs.catchall_ioproj, C->top()); 1002 } 1003 if (_callprojs.catchall_catchproj != nullptr) { 1004 _igvn.replace_node(_callprojs.catchall_catchproj, C->top()); 1005 } 1006 } 1007 1008 bool PhaseMacroExpand::eliminate_allocate_node(AllocateNode *alloc) { 1009 // If reallocation fails during deoptimization we'll pop all 1010 // interpreter frames for this compiled frame and that won't play 1011 // nice with JVMTI popframe. 1012 // We avoid this issue by eager reallocation when the popframe request 1013 // is received. 1014 if (!EliminateAllocations || !alloc->_is_non_escaping) { 1015 return false; 1016 } 1017 Node* klass = alloc->in(AllocateNode::KlassNode); 1018 const TypeKlassPtr* tklass = _igvn.type(klass)->is_klassptr(); 1019 Node* res = alloc->result_cast(); 1020 // Eliminate boxing allocations which are not used 1021 // regardless scalar replacable status. 1022 bool boxing_alloc = C->eliminate_boxing() && 1023 tklass->klass()->is_instance_klass() && 1024 tklass->klass()->as_instance_klass()->is_box_klass(); 1025 if (!alloc->_is_scalar_replaceable && (!boxing_alloc || (res != nullptr))) { 1026 return false; 1027 } 1028 1029 alloc->extract_projections(&_callprojs, false /*separate_io_proj*/, false /*do_asserts*/); 1030 1031 GrowableArray <SafePointNode *> safepoints; 1032 if (!can_eliminate_allocation(alloc, safepoints)) { 1033 return false; 1034 } 1035 1036 if (!alloc->_is_scalar_replaceable) { 1037 assert(res == nullptr, "sanity"); 1038 // We can only eliminate allocation if all debug info references 1039 // are already replaced with SafePointScalarObject because 1040 // we can't search for a fields value without instance_id. 1041 if (safepoints.length() > 0) { 1042 return false; 1043 } 1044 } 1045 1046 if (!scalar_replacement(alloc, safepoints)) { 1047 return false; 1048 } 1049 1050 CompileLog* log = C->log(); 1051 if (log != nullptr) { 1052 log->head("eliminate_allocation type='%d'", 1053 log->identify(tklass->klass())); 1054 JVMState* p = alloc->jvms(); 1055 while (p != nullptr) { 1056 log->elem("jvms bci='%d' method='%d'", p->bci(), log->identify(p->method())); 1057 p = p->caller(); 1058 } 1059 log->tail("eliminate_allocation"); 1060 } 1061 1062 process_users_of_allocation(alloc); 1063 1064 #ifndef PRODUCT 1065 if (PrintEliminateAllocations) { 1066 if (alloc->is_AllocateArray()) 1067 tty->print_cr("++++ Eliminated: %d AllocateArray", alloc->_idx); 1068 else 1069 tty->print_cr("++++ Eliminated: %d Allocate", alloc->_idx); 1070 } 1071 #endif 1072 1073 return true; 1074 } 1075 1076 bool PhaseMacroExpand::eliminate_boxing_node(CallStaticJavaNode *boxing) { 1077 // EA should remove all uses of non-escaping boxing node. 1078 if (!C->eliminate_boxing() || boxing->proj_out_or_null(TypeFunc::Parms) != nullptr) { 1079 return false; 1080 } 1081 1082 assert(boxing->result_cast() == nullptr, "unexpected boxing node result"); 1083 1084 boxing->extract_projections(&_callprojs, false /*separate_io_proj*/, false /*do_asserts*/); 1085 1086 const TypeTuple* r = boxing->tf()->range(); 1087 assert(r->cnt() > TypeFunc::Parms, "sanity"); 1088 const TypeInstPtr* t = r->field_at(TypeFunc::Parms)->isa_instptr(); 1089 assert(t != nullptr, "sanity"); 1090 1091 CompileLog* log = C->log(); 1092 if (log != nullptr) { 1093 log->head("eliminate_boxing type='%d'", 1094 log->identify(t->klass())); 1095 JVMState* p = boxing->jvms(); 1096 while (p != nullptr) { 1097 log->elem("jvms bci='%d' method='%d'", p->bci(), log->identify(p->method())); 1098 p = p->caller(); 1099 } 1100 log->tail("eliminate_boxing"); 1101 } 1102 1103 process_users_of_allocation(boxing); 1104 1105 #ifndef PRODUCT 1106 if (PrintEliminateAllocations) { 1107 tty->print("++++ Eliminated: %d ", boxing->_idx); 1108 boxing->method()->print_short_name(tty); 1109 tty->cr(); 1110 } 1111 #endif 1112 1113 return true; 1114 } 1115 1116 //---------------------------set_eden_pointers------------------------- 1117 void PhaseMacroExpand::set_eden_pointers(Node* &eden_top_adr, Node* &eden_end_adr) { 1118 if (UseTLAB) { // Private allocation: load from TLS 1119 Node* thread = transform_later(new ThreadLocalNode()); 1120 int tlab_top_offset = in_bytes(JavaThread::tlab_top_offset()); 1121 int tlab_end_offset = in_bytes(JavaThread::tlab_end_offset()); 1122 eden_top_adr = basic_plus_adr(top()/*not oop*/, thread, tlab_top_offset); 1123 eden_end_adr = basic_plus_adr(top()/*not oop*/, thread, tlab_end_offset); 1124 } else { // Shared allocation: load from globals 1125 CollectedHeap* ch = Universe::heap(); 1126 address top_adr = (address)ch->top_addr(); 1127 address end_adr = (address)ch->end_addr(); 1128 eden_top_adr = makecon(TypeRawPtr::make(top_adr)); 1129 eden_end_adr = basic_plus_adr(eden_top_adr, end_adr - top_adr); 1130 } 1131 } 1132 1133 1134 Node* PhaseMacroExpand::make_load(Node* ctl, Node* mem, Node* base, int offset, const Type* value_type, BasicType bt) { 1135 Node* adr = basic_plus_adr(base, offset); 1136 const TypePtr* adr_type = adr->bottom_type()->is_ptr(); 1137 Node* value = LoadNode::make(_igvn, ctl, mem, adr, adr_type, value_type, bt, MemNode::unordered); 1138 transform_later(value); 1139 return value; 1140 } 1141 1142 1143 Node* PhaseMacroExpand::make_store(Node* ctl, Node* mem, Node* base, int offset, Node* value, BasicType bt) { 1144 Node* adr = basic_plus_adr(base, offset); 1145 mem = StoreNode::make(_igvn, ctl, mem, adr, nullptr, value, bt, MemNode::unordered); 1146 transform_later(mem); 1147 return mem; 1148 } 1149 1150 //============================================================================= 1151 // 1152 // A L L O C A T I O N 1153 // 1154 // Allocation attempts to be fast in the case of frequent small objects. 1155 // It breaks down like this: 1156 // 1157 // 1) Size in doublewords is computed. This is a constant for objects and 1158 // variable for most arrays. Doubleword units are used to avoid size 1159 // overflow of huge doubleword arrays. We need doublewords in the end for 1160 // rounding. 1161 // 1162 // 2) Size is checked for being 'too large'. Too-large allocations will go 1163 // the slow path into the VM. The slow path can throw any required 1164 // exceptions, and does all the special checks for very large arrays. The 1165 // size test can constant-fold away for objects. For objects with 1166 // finalizers it constant-folds the otherway: you always go slow with 1167 // finalizers. 1168 // 1169 // 3) If NOT using TLABs, this is the contended loop-back point. 1170 // Load-Locked the heap top. If using TLABs normal-load the heap top. 1171 // 1172 // 4) Check that heap top + size*8 < max. If we fail go the slow ` route. 1173 // NOTE: "top+size*8" cannot wrap the 4Gig line! Here's why: for largish 1174 // "size*8" we always enter the VM, where "largish" is a constant picked small 1175 // enough that there's always space between the eden max and 4Gig (old space is 1176 // there so it's quite large) and large enough that the cost of entering the VM 1177 // is dwarfed by the cost to initialize the space. 1178 // 1179 // 5) If NOT using TLABs, Store-Conditional the adjusted heap top back 1180 // down. If contended, repeat at step 3. If using TLABs normal-store 1181 // adjusted heap top back down; there is no contention. 1182 // 1183 // 6) If !ZeroTLAB then Bulk-clear the object/array. Fill in klass & mark 1184 // fields. 1185 // 1186 // 7) Merge with the slow-path; cast the raw memory pointer to the correct 1187 // oop flavor. 1188 // 1189 //============================================================================= 1190 // FastAllocateSizeLimit value is in DOUBLEWORDS. 1191 // Allocations bigger than this always go the slow route. 1192 // This value must be small enough that allocation attempts that need to 1193 // trigger exceptions go the slow route. Also, it must be small enough so 1194 // that heap_top + size_in_bytes does not wrap around the 4Gig limit. 1195 //=============================================================================j// 1196 // %%% Here is an old comment from parseHelper.cpp; is it outdated? 1197 // The allocator will coalesce int->oop copies away. See comment in 1198 // coalesce.cpp about how this works. It depends critically on the exact 1199 // code shape produced here, so if you are changing this code shape 1200 // make sure the GC info for the heap-top is correct in and around the 1201 // slow-path call. 1202 // 1203 1204 void PhaseMacroExpand::expand_allocate_common( 1205 AllocateNode* alloc, // allocation node to be expanded 1206 Node* length, // array length for an array allocation 1207 const TypeFunc* slow_call_type, // Type of slow call 1208 address slow_call_address, // Address of slow call 1209 Node* valid_length_test // whether length is valid or not 1210 ) 1211 { 1212 Node* ctrl = alloc->in(TypeFunc::Control); 1213 Node* mem = alloc->in(TypeFunc::Memory); 1214 Node* i_o = alloc->in(TypeFunc::I_O); 1215 Node* size_in_bytes = alloc->in(AllocateNode::AllocSize); 1216 Node* klass_node = alloc->in(AllocateNode::KlassNode); 1217 Node* initial_slow_test = alloc->in(AllocateNode::InitialTest); 1218 assert(ctrl != nullptr, "must have control"); 1219 1220 // We need a Region and corresponding Phi's to merge the slow-path and fast-path results. 1221 // they will not be used if "always_slow" is set 1222 enum { slow_result_path = 1, fast_result_path = 2 }; 1223 Node *result_region = nullptr; 1224 Node *result_phi_rawmem = nullptr; 1225 Node *result_phi_rawoop = nullptr; 1226 Node *result_phi_i_o = nullptr; 1227 1228 // The initial slow comparison is a size check, the comparison 1229 // we want to do is a BoolTest::gt 1230 bool expand_fast_path = true; 1231 int tv = _igvn.find_int_con(initial_slow_test, -1); 1232 if (tv >= 0) { 1233 // InitialTest has constant result 1234 // 0 - can fit in TLAB 1235 // 1 - always too big or negative 1236 assert(tv <= 1, "0 or 1 if a constant"); 1237 expand_fast_path = (tv == 0); 1238 initial_slow_test = nullptr; 1239 } else { 1240 initial_slow_test = BoolNode::make_predicate(initial_slow_test, &_igvn); 1241 } 1242 1243 if (C->env()->dtrace_alloc_probes() || 1244 (!UseTLAB && !Universe::heap()->supports_inline_contig_alloc())) { 1245 // Force slow-path allocation 1246 expand_fast_path = false; 1247 initial_slow_test = nullptr; 1248 } 1249 1250 bool allocation_has_use = (alloc->result_cast() != nullptr); 1251 if (!allocation_has_use) { 1252 InitializeNode* init = alloc->initialization(); 1253 if (init != nullptr) { 1254 init->remove(&_igvn); 1255 } 1256 if (expand_fast_path && (initial_slow_test == nullptr)) { 1257 // Remove allocation node and return. 1258 // Size is a non-negative constant -> no initial check needed -> directly to fast path. 1259 // Also, no usages -> empty fast path -> no fall out to slow path -> nothing left. 1260 #ifndef PRODUCT 1261 if (PrintEliminateAllocations) { 1262 tty->print("NotUsed "); 1263 Node* res = alloc->proj_out_or_null(TypeFunc::Parms); 1264 if (res != nullptr) { 1265 res->dump(); 1266 } else { 1267 alloc->dump(); 1268 } 1269 } 1270 #endif 1271 yank_alloc_node(alloc); 1272 return; 1273 } 1274 } 1275 1276 enum { too_big_or_final_path = 1, need_gc_path = 2 }; 1277 Node *slow_region = nullptr; 1278 Node *toobig_false = ctrl; 1279 1280 // generate the initial test if necessary 1281 if (initial_slow_test != nullptr ) { 1282 assert (expand_fast_path, "Only need test if there is a fast path"); 1283 slow_region = new RegionNode(3); 1284 1285 // Now make the initial failure test. Usually a too-big test but 1286 // might be a TRUE for finalizers or a fancy class check for 1287 // newInstance0. 1288 IfNode *toobig_iff = new IfNode(ctrl, initial_slow_test, PROB_MIN, COUNT_UNKNOWN); 1289 transform_later(toobig_iff); 1290 // Plug the failing-too-big test into the slow-path region 1291 Node *toobig_true = new IfTrueNode( toobig_iff ); 1292 transform_later(toobig_true); 1293 slow_region ->init_req( too_big_or_final_path, toobig_true ); 1294 toobig_false = new IfFalseNode( toobig_iff ); 1295 transform_later(toobig_false); 1296 } else { 1297 // No initial test, just fall into next case 1298 assert(allocation_has_use || !expand_fast_path, "Should already have been handled"); 1299 toobig_false = ctrl; 1300 debug_only(slow_region = NodeSentinel); 1301 } 1302 1303 // If we are here there are several possibilities 1304 // - expand_fast_path is false - then only a slow path is expanded. That's it. 1305 // no_initial_check means a constant allocation. 1306 // - If check always evaluates to false -> expand_fast_path is false (see above) 1307 // - If check always evaluates to true -> directly into fast path (but may bailout to slowpath) 1308 // if !allocation_has_use the fast path is empty 1309 // if !allocation_has_use && no_initial_check 1310 // - Then there are no fastpath that can fall out to slowpath -> no allocation code at all. 1311 // removed by yank_alloc_node above. 1312 1313 Node *slow_mem = mem; // save the current memory state for slow path 1314 // generate the fast allocation code unless we know that the initial test will always go slow 1315 if (expand_fast_path) { 1316 // Fast path modifies only raw memory. 1317 if (mem->is_MergeMem()) { 1318 mem = mem->as_MergeMem()->memory_at(Compile::AliasIdxRaw); 1319 } 1320 1321 // allocate the Region and Phi nodes for the result 1322 result_region = new RegionNode(3); 1323 result_phi_rawmem = new PhiNode(result_region, Type::MEMORY, TypeRawPtr::BOTTOM); 1324 result_phi_i_o = new PhiNode(result_region, Type::ABIO); // I/O is used for Prefetch 1325 1326 // Grab regular I/O before optional prefetch may change it. 1327 // Slow-path does no I/O so just set it to the original I/O. 1328 result_phi_i_o->init_req(slow_result_path, i_o); 1329 1330 // Name successful fast-path variables 1331 Node* fast_oop_ctrl; 1332 Node* fast_oop_rawmem; 1333 if (allocation_has_use) { 1334 Node* needgc_ctrl = nullptr; 1335 result_phi_rawoop = new PhiNode(result_region, TypeRawPtr::BOTTOM); 1336 1337 intx prefetch_lines = length != nullptr ? AllocatePrefetchLines : AllocateInstancePrefetchLines; 1338 BarrierSetC2* bs = BarrierSet::barrier_set()->barrier_set_c2(); 1339 Node* fast_oop = bs->obj_allocate(this, mem, toobig_false, size_in_bytes, i_o, needgc_ctrl, 1340 fast_oop_ctrl, fast_oop_rawmem, 1341 prefetch_lines); 1342 1343 if (initial_slow_test != nullptr) { 1344 // This completes all paths into the slow merge point 1345 slow_region->init_req(need_gc_path, needgc_ctrl); 1346 transform_later(slow_region); 1347 } else { 1348 // No initial slow path needed! 1349 // Just fall from the need-GC path straight into the VM call. 1350 slow_region = needgc_ctrl; 1351 } 1352 1353 InitializeNode* init = alloc->initialization(); 1354 fast_oop_rawmem = initialize_object(alloc, 1355 fast_oop_ctrl, fast_oop_rawmem, fast_oop, 1356 klass_node, length, size_in_bytes); 1357 expand_initialize_membar(alloc, init, fast_oop_ctrl, fast_oop_rawmem); 1358 expand_dtrace_alloc_probe(alloc, fast_oop, fast_oop_ctrl, fast_oop_rawmem); 1359 1360 result_phi_rawoop->init_req(fast_result_path, fast_oop); 1361 } else { 1362 assert (initial_slow_test != nullptr, "sanity"); 1363 fast_oop_ctrl = toobig_false; 1364 fast_oop_rawmem = mem; 1365 transform_later(slow_region); 1366 } 1367 1368 // Plug in the successful fast-path into the result merge point 1369 result_region ->init_req(fast_result_path, fast_oop_ctrl); 1370 result_phi_i_o ->init_req(fast_result_path, i_o); 1371 result_phi_rawmem->init_req(fast_result_path, fast_oop_rawmem); 1372 } else { 1373 slow_region = ctrl; 1374 result_phi_i_o = i_o; // Rename it to use in the following code. 1375 } 1376 1377 // Generate slow-path call 1378 CallNode *call = new CallStaticJavaNode(slow_call_type, slow_call_address, 1379 OptoRuntime::stub_name(slow_call_address), 1380 TypePtr::BOTTOM); 1381 call->init_req(TypeFunc::Control, slow_region); 1382 call->init_req(TypeFunc::I_O, top()); // does no i/o 1383 call->init_req(TypeFunc::Memory, slow_mem); // may gc ptrs 1384 call->init_req(TypeFunc::ReturnAdr, alloc->in(TypeFunc::ReturnAdr)); 1385 call->init_req(TypeFunc::FramePtr, alloc->in(TypeFunc::FramePtr)); 1386 1387 call->init_req(TypeFunc::Parms+0, klass_node); 1388 if (length != nullptr) { 1389 call->init_req(TypeFunc::Parms+1, length); 1390 } 1391 1392 // Copy debug information and adjust JVMState information, then replace 1393 // allocate node with the call 1394 call->copy_call_debug_info(&_igvn, alloc); 1395 // For array allocations, copy the valid length check to the call node so Compile::final_graph_reshaping() can verify 1396 // that the call has the expected number of CatchProj nodes (in case the allocation always fails and the fallthrough 1397 // path dies). 1398 if (valid_length_test != nullptr) { 1399 call->add_req(valid_length_test); 1400 } 1401 if (expand_fast_path) { 1402 call->set_cnt(PROB_UNLIKELY_MAG(4)); // Same effect as RC_UNCOMMON. 1403 } else { 1404 // Hook i_o projection to avoid its elimination during allocation 1405 // replacement (when only a slow call is generated). 1406 call->set_req(TypeFunc::I_O, result_phi_i_o); 1407 } 1408 _igvn.replace_node(alloc, call); 1409 transform_later(call); 1410 1411 // Identify the output projections from the allocate node and 1412 // adjust any references to them. 1413 // The control and io projections look like: 1414 // 1415 // v---Proj(ctrl) <-----+ v---CatchProj(ctrl) 1416 // Allocate Catch 1417 // ^---Proj(io) <-------+ ^---CatchProj(io) 1418 // 1419 // We are interested in the CatchProj nodes. 1420 // 1421 call->extract_projections(&_callprojs, false /*separate_io_proj*/, false /*do_asserts*/); 1422 1423 // An allocate node has separate memory projections for the uses on 1424 // the control and i_o paths. Replace the control memory projection with 1425 // result_phi_rawmem (unless we are only generating a slow call when 1426 // both memory projections are combined) 1427 if (expand_fast_path && _callprojs.fallthrough_memproj != nullptr) { 1428 migrate_outs(_callprojs.fallthrough_memproj, result_phi_rawmem); 1429 } 1430 // Now change uses of catchall_memproj to use fallthrough_memproj and delete 1431 // catchall_memproj so we end up with a call that has only 1 memory projection. 1432 if (_callprojs.catchall_memproj != nullptr ) { 1433 if (_callprojs.fallthrough_memproj == nullptr) { 1434 _callprojs.fallthrough_memproj = new ProjNode(call, TypeFunc::Memory); 1435 transform_later(_callprojs.fallthrough_memproj); 1436 } 1437 migrate_outs(_callprojs.catchall_memproj, _callprojs.fallthrough_memproj); 1438 _igvn.remove_dead_node(_callprojs.catchall_memproj); 1439 } 1440 1441 // An allocate node has separate i_o projections for the uses on the control 1442 // and i_o paths. Always replace the control i_o projection with result i_o 1443 // otherwise incoming i_o become dead when only a slow call is generated 1444 // (it is different from memory projections where both projections are 1445 // combined in such case). 1446 if (_callprojs.fallthrough_ioproj != nullptr) { 1447 migrate_outs(_callprojs.fallthrough_ioproj, result_phi_i_o); 1448 } 1449 // Now change uses of catchall_ioproj to use fallthrough_ioproj and delete 1450 // catchall_ioproj so we end up with a call that has only 1 i_o projection. 1451 if (_callprojs.catchall_ioproj != nullptr ) { 1452 if (_callprojs.fallthrough_ioproj == nullptr) { 1453 _callprojs.fallthrough_ioproj = new ProjNode(call, TypeFunc::I_O); 1454 transform_later(_callprojs.fallthrough_ioproj); 1455 } 1456 migrate_outs(_callprojs.catchall_ioproj, _callprojs.fallthrough_ioproj); 1457 _igvn.remove_dead_node(_callprojs.catchall_ioproj); 1458 } 1459 1460 // if we generated only a slow call, we are done 1461 if (!expand_fast_path) { 1462 // Now we can unhook i_o. 1463 if (result_phi_i_o->outcnt() > 1) { 1464 call->set_req(TypeFunc::I_O, top()); 1465 } else { 1466 assert(result_phi_i_o->unique_ctrl_out() == call, "sanity"); 1467 // Case of new array with negative size known during compilation. 1468 // AllocateArrayNode::Ideal() optimization disconnect unreachable 1469 // following code since call to runtime will throw exception. 1470 // As result there will be no users of i_o after the call. 1471 // Leave i_o attached to this call to avoid problems in preceding graph. 1472 } 1473 return; 1474 } 1475 1476 if (_callprojs.fallthrough_catchproj != nullptr) { 1477 ctrl = _callprojs.fallthrough_catchproj->clone(); 1478 transform_later(ctrl); 1479 _igvn.replace_node(_callprojs.fallthrough_catchproj, result_region); 1480 } else { 1481 ctrl = top(); 1482 } 1483 Node *slow_result; 1484 if (_callprojs.resproj == nullptr) { 1485 // no uses of the allocation result 1486 slow_result = top(); 1487 } else { 1488 slow_result = _callprojs.resproj->clone(); 1489 transform_later(slow_result); 1490 _igvn.replace_node(_callprojs.resproj, result_phi_rawoop); 1491 } 1492 1493 // Plug slow-path into result merge point 1494 result_region->init_req( slow_result_path, ctrl); 1495 transform_later(result_region); 1496 if (allocation_has_use) { 1497 result_phi_rawoop->init_req(slow_result_path, slow_result); 1498 transform_later(result_phi_rawoop); 1499 } 1500 result_phi_rawmem->init_req(slow_result_path, _callprojs.fallthrough_memproj); 1501 transform_later(result_phi_rawmem); 1502 transform_later(result_phi_i_o); 1503 // This completes all paths into the result merge point 1504 } 1505 1506 // Remove alloc node that has no uses. 1507 void PhaseMacroExpand::yank_alloc_node(AllocateNode* alloc) { 1508 Node* ctrl = alloc->in(TypeFunc::Control); 1509 Node* mem = alloc->in(TypeFunc::Memory); 1510 Node* i_o = alloc->in(TypeFunc::I_O); 1511 1512 alloc->extract_projections(&_callprojs, false /*separate_io_proj*/, false /*do_asserts*/); 1513 if (_callprojs.resproj != nullptr) { 1514 for (DUIterator_Fast imax, i = _callprojs.resproj->fast_outs(imax); i < imax; i++) { 1515 Node* use = _callprojs.resproj->fast_out(i); 1516 use->isa_MemBar()->remove(&_igvn); 1517 --imax; 1518 --i; // back up iterator 1519 } 1520 assert(_callprojs.resproj->outcnt() == 0, "all uses must be deleted"); 1521 _igvn.remove_dead_node(_callprojs.resproj); 1522 } 1523 if (_callprojs.fallthrough_catchproj != nullptr) { 1524 migrate_outs(_callprojs.fallthrough_catchproj, ctrl); 1525 _igvn.remove_dead_node(_callprojs.fallthrough_catchproj); 1526 } 1527 if (_callprojs.catchall_catchproj != nullptr) { 1528 _igvn.rehash_node_delayed(_callprojs.catchall_catchproj); 1529 _callprojs.catchall_catchproj->set_req(0, top()); 1530 } 1531 if (_callprojs.fallthrough_proj != nullptr) { 1532 Node* catchnode = _callprojs.fallthrough_proj->unique_ctrl_out(); 1533 _igvn.remove_dead_node(catchnode); 1534 _igvn.remove_dead_node(_callprojs.fallthrough_proj); 1535 } 1536 if (_callprojs.fallthrough_memproj != nullptr) { 1537 migrate_outs(_callprojs.fallthrough_memproj, mem); 1538 _igvn.remove_dead_node(_callprojs.fallthrough_memproj); 1539 } 1540 if (_callprojs.fallthrough_ioproj != nullptr) { 1541 migrate_outs(_callprojs.fallthrough_ioproj, i_o); 1542 _igvn.remove_dead_node(_callprojs.fallthrough_ioproj); 1543 } 1544 if (_callprojs.catchall_memproj != nullptr) { 1545 _igvn.rehash_node_delayed(_callprojs.catchall_memproj); 1546 _callprojs.catchall_memproj->set_req(0, top()); 1547 } 1548 if (_callprojs.catchall_ioproj != nullptr) { 1549 _igvn.rehash_node_delayed(_callprojs.catchall_ioproj); 1550 _callprojs.catchall_ioproj->set_req(0, top()); 1551 } 1552 #ifndef PRODUCT 1553 if (PrintEliminateAllocations) { 1554 if (alloc->is_AllocateArray()) { 1555 tty->print_cr("++++ Eliminated: %d AllocateArray", alloc->_idx); 1556 } else { 1557 tty->print_cr("++++ Eliminated: %d Allocate", alloc->_idx); 1558 } 1559 } 1560 #endif 1561 _igvn.remove_dead_node(alloc); 1562 } 1563 1564 void PhaseMacroExpand::expand_initialize_membar(AllocateNode* alloc, InitializeNode* init, 1565 Node*& fast_oop_ctrl, Node*& fast_oop_rawmem) { 1566 // If initialization is performed by an array copy, any required 1567 // MemBarStoreStore was already added. If the object does not 1568 // escape no need for a MemBarStoreStore. If the object does not 1569 // escape in its initializer and memory barrier (MemBarStoreStore or 1570 // stronger) is already added at exit of initializer, also no need 1571 // for a MemBarStoreStore. Otherwise we need a MemBarStoreStore 1572 // so that stores that initialize this object can't be reordered 1573 // with a subsequent store that makes this object accessible by 1574 // other threads. 1575 // Other threads include java threads and JVM internal threads 1576 // (for example concurrent GC threads). Current concurrent GC 1577 // implementation: G1 will not scan newly created object, 1578 // so it's safe to skip storestore barrier when allocation does 1579 // not escape. 1580 if (!alloc->does_not_escape_thread() && 1581 !alloc->is_allocation_MemBar_redundant() && 1582 (init == nullptr || !init->is_complete_with_arraycopy())) { 1583 if (init == nullptr || init->req() < InitializeNode::RawStores) { 1584 // No InitializeNode or no stores captured by zeroing 1585 // elimination. Simply add the MemBarStoreStore after object 1586 // initialization. 1587 MemBarNode* mb = MemBarNode::make(C, Op_MemBarStoreStore, Compile::AliasIdxBot); 1588 transform_later(mb); 1589 1590 mb->init_req(TypeFunc::Memory, fast_oop_rawmem); 1591 mb->init_req(TypeFunc::Control, fast_oop_ctrl); 1592 fast_oop_ctrl = new ProjNode(mb, TypeFunc::Control); 1593 transform_later(fast_oop_ctrl); 1594 fast_oop_rawmem = new ProjNode(mb, TypeFunc::Memory); 1595 transform_later(fast_oop_rawmem); 1596 } else { 1597 // Add the MemBarStoreStore after the InitializeNode so that 1598 // all stores performing the initialization that were moved 1599 // before the InitializeNode happen before the storestore 1600 // barrier. 1601 1602 Node* init_ctrl = init->proj_out_or_null(TypeFunc::Control); 1603 Node* init_mem = init->proj_out_or_null(TypeFunc::Memory); 1604 1605 MemBarNode* mb = MemBarNode::make(C, Op_MemBarStoreStore, Compile::AliasIdxBot); 1606 transform_later(mb); 1607 1608 Node* ctrl = new ProjNode(init, TypeFunc::Control); 1609 transform_later(ctrl); 1610 Node* mem = new ProjNode(init, TypeFunc::Memory); 1611 transform_later(mem); 1612 1613 // The MemBarStoreStore depends on control and memory coming 1614 // from the InitializeNode 1615 mb->init_req(TypeFunc::Memory, mem); 1616 mb->init_req(TypeFunc::Control, ctrl); 1617 1618 ctrl = new ProjNode(mb, TypeFunc::Control); 1619 transform_later(ctrl); 1620 mem = new ProjNode(mb, TypeFunc::Memory); 1621 transform_later(mem); 1622 1623 // All nodes that depended on the InitializeNode for control 1624 // and memory must now depend on the MemBarNode that itself 1625 // depends on the InitializeNode 1626 if (init_ctrl != nullptr) { 1627 _igvn.replace_node(init_ctrl, ctrl); 1628 } 1629 if (init_mem != nullptr) { 1630 _igvn.replace_node(init_mem, mem); 1631 } 1632 } 1633 } 1634 } 1635 1636 void PhaseMacroExpand::expand_dtrace_alloc_probe(AllocateNode* alloc, Node* oop, 1637 Node*& ctrl, Node*& rawmem) { 1638 if (C->env()->dtrace_extended_probes()) { 1639 // Slow-path call 1640 int size = TypeFunc::Parms + 2; 1641 CallLeafNode *call = new CallLeafNode(OptoRuntime::dtrace_object_alloc_Type(), 1642 CAST_FROM_FN_PTR(address, SharedRuntime::dtrace_object_alloc_base), 1643 "dtrace_object_alloc", 1644 TypeRawPtr::BOTTOM); 1645 1646 // Get base of thread-local storage area 1647 Node* thread = new ThreadLocalNode(); 1648 transform_later(thread); 1649 1650 call->init_req(TypeFunc::Parms + 0, thread); 1651 call->init_req(TypeFunc::Parms + 1, oop); 1652 call->init_req(TypeFunc::Control, ctrl); 1653 call->init_req(TypeFunc::I_O , top()); // does no i/o 1654 call->init_req(TypeFunc::Memory , ctrl); 1655 call->init_req(TypeFunc::ReturnAdr, alloc->in(TypeFunc::ReturnAdr)); 1656 call->init_req(TypeFunc::FramePtr, alloc->in(TypeFunc::FramePtr)); 1657 transform_later(call); 1658 ctrl = new ProjNode(call, TypeFunc::Control); 1659 transform_later(ctrl); 1660 rawmem = new ProjNode(call, TypeFunc::Memory); 1661 transform_later(rawmem); 1662 } 1663 } 1664 1665 // Helper for PhaseMacroExpand::expand_allocate_common. 1666 // Initializes the newly-allocated storage. 1667 Node* 1668 PhaseMacroExpand::initialize_object(AllocateNode* alloc, 1669 Node* control, Node* rawmem, Node* object, 1670 Node* klass_node, Node* length, 1671 Node* size_in_bytes) { 1672 InitializeNode* init = alloc->initialization(); 1673 // Store the klass & mark bits 1674 Node* mark_node = alloc->make_ideal_mark(&_igvn, object, control, rawmem); 1675 if (!mark_node->is_Con()) { 1676 transform_later(mark_node); 1677 } 1678 rawmem = make_store(control, rawmem, object, oopDesc::mark_offset_in_bytes(), mark_node, TypeX_X->basic_type()); 1679 1680 if (!UseCompactObjectHeaders) { 1681 rawmem = make_store(control, rawmem, object, oopDesc::klass_offset_in_bytes(), klass_node, T_METADATA); 1682 } 1683 1684 int header_size = alloc->minimum_header_size(); // conservatively small 1685 1686 // Array length 1687 if (length != nullptr) { // Arrays need length field 1688 rawmem = make_store(control, rawmem, object, arrayOopDesc::length_offset_in_bytes(), length, T_INT); 1689 // conservatively small header size: 1690 header_size = arrayOopDesc::base_offset_in_bytes(T_BYTE); 1691 ciKlass* k = _igvn.type(klass_node)->is_klassptr()->klass(); 1692 if (k->is_array_klass()) // we know the exact header size in most cases: 1693 header_size = Klass::layout_helper_header_size(k->layout_helper()); 1694 } 1695 1696 // Clear the object body, if necessary. 1697 if (init == nullptr) { 1698 // The init has somehow disappeared; be cautious and clear everything. 1699 // 1700 // This can happen if a node is allocated but an uncommon trap occurs 1701 // immediately. In this case, the Initialize gets associated with the 1702 // trap, and may be placed in a different (outer) loop, if the Allocate 1703 // is in a loop. If (this is rare) the inner loop gets unrolled, then 1704 // there can be two Allocates to one Initialize. The answer in all these 1705 // edge cases is safety first. It is always safe to clear immediately 1706 // within an Allocate, and then (maybe or maybe not) clear some more later. 1707 if (!(UseTLAB && ZeroTLAB)) { 1708 rawmem = ClearArrayNode::clear_memory(control, rawmem, object, 1709 header_size, size_in_bytes, 1710 &_igvn); 1711 } 1712 } else { 1713 if (!init->is_complete()) { 1714 // Try to win by zeroing only what the init does not store. 1715 // We can also try to do some peephole optimizations, 1716 // such as combining some adjacent subword stores. 1717 rawmem = init->complete_stores(control, rawmem, object, 1718 header_size, size_in_bytes, &_igvn); 1719 } 1720 // We have no more use for this link, since the AllocateNode goes away: 1721 init->set_req(InitializeNode::RawAddress, top()); 1722 // (If we keep the link, it just confuses the register allocator, 1723 // who thinks he sees a real use of the address by the membar.) 1724 } 1725 1726 return rawmem; 1727 } 1728 1729 // Generate prefetch instructions for next allocations. 1730 Node* PhaseMacroExpand::prefetch_allocation(Node* i_o, Node*& needgc_false, 1731 Node*& contended_phi_rawmem, 1732 Node* old_eden_top, Node* new_eden_top, 1733 intx lines) { 1734 enum { fall_in_path = 1, pf_path = 2 }; 1735 if( UseTLAB && AllocatePrefetchStyle == 2 ) { 1736 // Generate prefetch allocation with watermark check. 1737 // As an allocation hits the watermark, we will prefetch starting 1738 // at a "distance" away from watermark. 1739 1740 Node *pf_region = new RegionNode(3); 1741 Node *pf_phi_rawmem = new PhiNode( pf_region, Type::MEMORY, 1742 TypeRawPtr::BOTTOM ); 1743 // I/O is used for Prefetch 1744 Node *pf_phi_abio = new PhiNode( pf_region, Type::ABIO ); 1745 1746 Node *thread = new ThreadLocalNode(); 1747 transform_later(thread); 1748 1749 Node *eden_pf_adr = new AddPNode( top()/*not oop*/, thread, 1750 _igvn.MakeConX(in_bytes(JavaThread::tlab_pf_top_offset())) ); 1751 transform_later(eden_pf_adr); 1752 1753 Node *old_pf_wm = new LoadPNode(needgc_false, 1754 contended_phi_rawmem, eden_pf_adr, 1755 TypeRawPtr::BOTTOM, TypeRawPtr::BOTTOM, 1756 MemNode::unordered); 1757 transform_later(old_pf_wm); 1758 1759 // check against new_eden_top 1760 Node *need_pf_cmp = new CmpPNode( new_eden_top, old_pf_wm ); 1761 transform_later(need_pf_cmp); 1762 Node *need_pf_bol = new BoolNode( need_pf_cmp, BoolTest::ge ); 1763 transform_later(need_pf_bol); 1764 IfNode *need_pf_iff = new IfNode( needgc_false, need_pf_bol, 1765 PROB_UNLIKELY_MAG(4), COUNT_UNKNOWN ); 1766 transform_later(need_pf_iff); 1767 1768 // true node, add prefetchdistance 1769 Node *need_pf_true = new IfTrueNode( need_pf_iff ); 1770 transform_later(need_pf_true); 1771 1772 Node *need_pf_false = new IfFalseNode( need_pf_iff ); 1773 transform_later(need_pf_false); 1774 1775 Node *new_pf_wmt = new AddPNode( top(), old_pf_wm, 1776 _igvn.MakeConX(AllocatePrefetchDistance) ); 1777 transform_later(new_pf_wmt ); 1778 new_pf_wmt->set_req(0, need_pf_true); 1779 1780 Node *store_new_wmt = new StorePNode(need_pf_true, 1781 contended_phi_rawmem, eden_pf_adr, 1782 TypeRawPtr::BOTTOM, new_pf_wmt, 1783 MemNode::unordered); 1784 transform_later(store_new_wmt); 1785 1786 // adding prefetches 1787 pf_phi_abio->init_req( fall_in_path, i_o ); 1788 1789 Node *prefetch_adr; 1790 Node *prefetch; 1791 uint step_size = AllocatePrefetchStepSize; 1792 uint distance = 0; 1793 1794 for ( intx i = 0; i < lines; i++ ) { 1795 prefetch_adr = new AddPNode( old_pf_wm, new_pf_wmt, 1796 _igvn.MakeConX(distance) ); 1797 transform_later(prefetch_adr); 1798 prefetch = new PrefetchAllocationNode( i_o, prefetch_adr ); 1799 transform_later(prefetch); 1800 distance += step_size; 1801 i_o = prefetch; 1802 } 1803 pf_phi_abio->set_req( pf_path, i_o ); 1804 1805 pf_region->init_req( fall_in_path, need_pf_false ); 1806 pf_region->init_req( pf_path, need_pf_true ); 1807 1808 pf_phi_rawmem->init_req( fall_in_path, contended_phi_rawmem ); 1809 pf_phi_rawmem->init_req( pf_path, store_new_wmt ); 1810 1811 transform_later(pf_region); 1812 transform_later(pf_phi_rawmem); 1813 transform_later(pf_phi_abio); 1814 1815 needgc_false = pf_region; 1816 contended_phi_rawmem = pf_phi_rawmem; 1817 i_o = pf_phi_abio; 1818 } else if( UseTLAB && AllocatePrefetchStyle == 3 ) { 1819 // Insert a prefetch instruction for each allocation. 1820 // This code is used to generate 1 prefetch instruction per cache line. 1821 1822 // Generate several prefetch instructions. 1823 uint step_size = AllocatePrefetchStepSize; 1824 uint distance = AllocatePrefetchDistance; 1825 1826 // Next cache address. 1827 Node *cache_adr = new AddPNode(old_eden_top, old_eden_top, 1828 _igvn.MakeConX(step_size + distance)); 1829 transform_later(cache_adr); 1830 cache_adr = new CastP2XNode(needgc_false, cache_adr); 1831 transform_later(cache_adr); 1832 // Address is aligned to execute prefetch to the beginning of cache line size 1833 // (it is important when BIS instruction is used on SPARC as prefetch). 1834 Node* mask = _igvn.MakeConX(~(intptr_t)(step_size-1)); 1835 cache_adr = new AndXNode(cache_adr, mask); 1836 transform_later(cache_adr); 1837 cache_adr = new CastX2PNode(cache_adr); 1838 transform_later(cache_adr); 1839 1840 // Prefetch 1841 Node *prefetch = new PrefetchAllocationNode( contended_phi_rawmem, cache_adr ); 1842 prefetch->set_req(0, needgc_false); 1843 transform_later(prefetch); 1844 contended_phi_rawmem = prefetch; 1845 Node *prefetch_adr; 1846 distance = step_size; 1847 for ( intx i = 1; i < lines; i++ ) { 1848 prefetch_adr = new AddPNode( cache_adr, cache_adr, 1849 _igvn.MakeConX(distance) ); 1850 transform_later(prefetch_adr); 1851 prefetch = new PrefetchAllocationNode( contended_phi_rawmem, prefetch_adr ); 1852 transform_later(prefetch); 1853 distance += step_size; 1854 contended_phi_rawmem = prefetch; 1855 } 1856 } else if( AllocatePrefetchStyle > 0 ) { 1857 // Insert a prefetch for each allocation only on the fast-path 1858 Node *prefetch_adr; 1859 Node *prefetch; 1860 // Generate several prefetch instructions. 1861 uint step_size = AllocatePrefetchStepSize; 1862 uint distance = AllocatePrefetchDistance; 1863 for ( intx i = 0; i < lines; i++ ) { 1864 prefetch_adr = new AddPNode( old_eden_top, new_eden_top, 1865 _igvn.MakeConX(distance) ); 1866 transform_later(prefetch_adr); 1867 prefetch = new PrefetchAllocationNode( i_o, prefetch_adr ); 1868 // Do not let it float too high, since if eden_top == eden_end, 1869 // both might be null. 1870 if( i == 0 ) { // Set control for first prefetch, next follows it 1871 prefetch->init_req(0, needgc_false); 1872 } 1873 transform_later(prefetch); 1874 distance += step_size; 1875 i_o = prefetch; 1876 } 1877 } 1878 return i_o; 1879 } 1880 1881 1882 void PhaseMacroExpand::expand_allocate(AllocateNode *alloc) { 1883 expand_allocate_common(alloc, nullptr, 1884 OptoRuntime::new_instance_Type(), 1885 OptoRuntime::new_instance_Java(), nullptr); 1886 } 1887 1888 void PhaseMacroExpand::expand_allocate_array(AllocateArrayNode *alloc) { 1889 Node* length = alloc->in(AllocateNode::ALength); 1890 Node* valid_length_test = alloc->in(AllocateNode::ValidLengthTest); 1891 InitializeNode* init = alloc->initialization(); 1892 Node* klass_node = alloc->in(AllocateNode::KlassNode); 1893 ciKlass* k = _igvn.type(klass_node)->is_klassptr()->klass(); 1894 address slow_call_address; // Address of slow call 1895 if (init != nullptr && init->is_complete_with_arraycopy() && 1896 k->is_type_array_klass()) { 1897 // Don't zero type array during slow allocation in VM since 1898 // it will be initialized later by arraycopy in compiled code. 1899 slow_call_address = OptoRuntime::new_array_nozero_Java(); 1900 } else { 1901 slow_call_address = OptoRuntime::new_array_Java(); 1902 } 1903 expand_allocate_common(alloc, length, 1904 OptoRuntime::new_array_Type(), 1905 slow_call_address, valid_length_test); 1906 } 1907 1908 //-------------------mark_eliminated_box---------------------------------- 1909 // 1910 // During EA obj may point to several objects but after few ideal graph 1911 // transformations (CCP) it may point to only one non escaping object 1912 // (but still using phi), corresponding locks and unlocks will be marked 1913 // for elimination. Later obj could be replaced with a new node (new phi) 1914 // and which does not have escape information. And later after some graph 1915 // reshape other locks and unlocks (which were not marked for elimination 1916 // before) are connected to this new obj (phi) but they still will not be 1917 // marked for elimination since new obj has no escape information. 1918 // Mark all associated (same box and obj) lock and unlock nodes for 1919 // elimination if some of them marked already. 1920 void PhaseMacroExpand::mark_eliminated_box(Node* oldbox, Node* obj) { 1921 if (oldbox->as_BoxLock()->is_eliminated()) { 1922 return; // This BoxLock node was processed already. 1923 } 1924 // New implementation (EliminateNestedLocks) has separate BoxLock 1925 // node for each locked region so mark all associated locks/unlocks as 1926 // eliminated even if different objects are referenced in one locked region 1927 // (for example, OSR compilation of nested loop inside locked scope). 1928 if (EliminateNestedLocks || 1929 oldbox->as_BoxLock()->is_simple_lock_region(nullptr, obj, nullptr)) { 1930 // Box is used only in one lock region. Mark this box as eliminated. 1931 _igvn.hash_delete(oldbox); 1932 oldbox->as_BoxLock()->set_eliminated(); // This changes box's hash value 1933 _igvn.hash_insert(oldbox); 1934 1935 for (uint i = 0; i < oldbox->outcnt(); i++) { 1936 Node* u = oldbox->raw_out(i); 1937 if (u->is_AbstractLock() && !u->as_AbstractLock()->is_non_esc_obj()) { 1938 AbstractLockNode* alock = u->as_AbstractLock(); 1939 // Check lock's box since box could be referenced by Lock's debug info. 1940 if (alock->box_node() == oldbox) { 1941 // Mark eliminated all related locks and unlocks. 1942 #ifdef ASSERT 1943 alock->log_lock_optimization(C, "eliminate_lock_set_non_esc4"); 1944 #endif 1945 alock->set_non_esc_obj(); 1946 } 1947 } 1948 } 1949 return; 1950 } 1951 1952 // Create new "eliminated" BoxLock node and use it in monitor debug info 1953 // instead of oldbox for the same object. 1954 BoxLockNode* newbox = oldbox->clone()->as_BoxLock(); 1955 1956 // Note: BoxLock node is marked eliminated only here and it is used 1957 // to indicate that all associated lock and unlock nodes are marked 1958 // for elimination. 1959 newbox->set_eliminated(); 1960 transform_later(newbox); 1961 1962 // Replace old box node with new box for all users of the same object. 1963 for (uint i = 0; i < oldbox->outcnt();) { 1964 bool next_edge = true; 1965 1966 Node* u = oldbox->raw_out(i); 1967 if (u->is_AbstractLock()) { 1968 AbstractLockNode* alock = u->as_AbstractLock(); 1969 if (alock->box_node() == oldbox && alock->obj_node()->eqv_uncast(obj)) { 1970 // Replace Box and mark eliminated all related locks and unlocks. 1971 #ifdef ASSERT 1972 alock->log_lock_optimization(C, "eliminate_lock_set_non_esc5"); 1973 #endif 1974 alock->set_non_esc_obj(); 1975 _igvn.rehash_node_delayed(alock); 1976 alock->set_box_node(newbox); 1977 next_edge = false; 1978 } 1979 } 1980 if (u->is_FastLock() && u->as_FastLock()->obj_node()->eqv_uncast(obj)) { 1981 FastLockNode* flock = u->as_FastLock(); 1982 assert(flock->box_node() == oldbox, "sanity"); 1983 _igvn.rehash_node_delayed(flock); 1984 flock->set_box_node(newbox); 1985 next_edge = false; 1986 } 1987 1988 // Replace old box in monitor debug info. 1989 if (u->is_SafePoint() && u->as_SafePoint()->jvms()) { 1990 SafePointNode* sfn = u->as_SafePoint(); 1991 JVMState* youngest_jvms = sfn->jvms(); 1992 int max_depth = youngest_jvms->depth(); 1993 for (int depth = 1; depth <= max_depth; depth++) { 1994 JVMState* jvms = youngest_jvms->of_depth(depth); 1995 int num_mon = jvms->nof_monitors(); 1996 // Loop over monitors 1997 for (int idx = 0; idx < num_mon; idx++) { 1998 Node* obj_node = sfn->monitor_obj(jvms, idx); 1999 Node* box_node = sfn->monitor_box(jvms, idx); 2000 if (box_node == oldbox && obj_node->eqv_uncast(obj)) { 2001 int j = jvms->monitor_box_offset(idx); 2002 _igvn.replace_input_of(u, j, newbox); 2003 next_edge = false; 2004 } 2005 } 2006 } 2007 } 2008 if (next_edge) i++; 2009 } 2010 } 2011 2012 //-----------------------mark_eliminated_locking_nodes----------------------- 2013 void PhaseMacroExpand::mark_eliminated_locking_nodes(AbstractLockNode *alock) { 2014 if (EliminateNestedLocks) { 2015 if (alock->is_nested()) { 2016 assert(alock->box_node()->as_BoxLock()->is_eliminated(), "sanity"); 2017 return; 2018 } else if (!alock->is_non_esc_obj()) { // Not eliminated or coarsened 2019 // Only Lock node has JVMState needed here. 2020 // Not that preceding claim is documented anywhere else. 2021 if (alock->jvms() != nullptr) { 2022 if (alock->as_Lock()->is_nested_lock_region()) { 2023 // Mark eliminated related nested locks and unlocks. 2024 Node* obj = alock->obj_node(); 2025 BoxLockNode* box_node = alock->box_node()->as_BoxLock(); 2026 assert(!box_node->is_eliminated(), "should not be marked yet"); 2027 // Note: BoxLock node is marked eliminated only here 2028 // and it is used to indicate that all associated lock 2029 // and unlock nodes are marked for elimination. 2030 box_node->set_eliminated(); // Box's hash is always NO_HASH here 2031 for (uint i = 0; i < box_node->outcnt(); i++) { 2032 Node* u = box_node->raw_out(i); 2033 if (u->is_AbstractLock()) { 2034 alock = u->as_AbstractLock(); 2035 if (alock->box_node() == box_node) { 2036 // Verify that this Box is referenced only by related locks. 2037 assert(alock->obj_node()->eqv_uncast(obj), ""); 2038 // Mark all related locks and unlocks. 2039 #ifdef ASSERT 2040 alock->log_lock_optimization(C, "eliminate_lock_set_nested"); 2041 #endif 2042 alock->set_nested(); 2043 } 2044 } 2045 } 2046 } else { 2047 #ifdef ASSERT 2048 alock->log_lock_optimization(C, "eliminate_lock_NOT_nested_lock_region"); 2049 if (C->log() != nullptr) 2050 alock->as_Lock()->is_nested_lock_region(C); // rerun for debugging output 2051 #endif 2052 } 2053 } 2054 return; 2055 } 2056 // Process locks for non escaping object 2057 assert(alock->is_non_esc_obj(), ""); 2058 } // EliminateNestedLocks 2059 2060 if (alock->is_non_esc_obj()) { // Lock is used for non escaping object 2061 // Look for all locks of this object and mark them and 2062 // corresponding BoxLock nodes as eliminated. 2063 Node* obj = alock->obj_node(); 2064 for (uint j = 0; j < obj->outcnt(); j++) { 2065 Node* o = obj->raw_out(j); 2066 if (o->is_AbstractLock() && 2067 o->as_AbstractLock()->obj_node()->eqv_uncast(obj)) { 2068 alock = o->as_AbstractLock(); 2069 Node* box = alock->box_node(); 2070 // Replace old box node with new eliminated box for all users 2071 // of the same object and mark related locks as eliminated. 2072 mark_eliminated_box(box, obj); 2073 } 2074 } 2075 } 2076 } 2077 2078 // we have determined that this lock/unlock can be eliminated, we simply 2079 // eliminate the node without expanding it. 2080 // 2081 // Note: The membar's associated with the lock/unlock are currently not 2082 // eliminated. This should be investigated as a future enhancement. 2083 // 2084 bool PhaseMacroExpand::eliminate_locking_node(AbstractLockNode *alock) { 2085 2086 if (!alock->is_eliminated()) { 2087 return false; 2088 } 2089 #ifdef ASSERT 2090 if (!alock->is_coarsened()) { 2091 // Check that new "eliminated" BoxLock node is created. 2092 BoxLockNode* oldbox = alock->box_node()->as_BoxLock(); 2093 assert(oldbox->is_eliminated(), "should be done already"); 2094 } 2095 #endif 2096 2097 alock->log_lock_optimization(C, "eliminate_lock"); 2098 2099 #ifndef PRODUCT 2100 if (PrintEliminateLocks) { 2101 tty->print_cr("++++ Eliminated: %d %s '%s'", alock->_idx, (alock->is_Lock() ? "Lock" : "Unlock"), alock->kind_as_string()); 2102 } 2103 #endif 2104 2105 Node* mem = alock->in(TypeFunc::Memory); 2106 Node* ctrl = alock->in(TypeFunc::Control); 2107 guarantee(ctrl != nullptr, "missing control projection, cannot replace_node() with null"); 2108 2109 alock->extract_projections(&_callprojs, false /*separate_io_proj*/, false /*do_asserts*/); 2110 // There are 2 projections from the lock. The lock node will 2111 // be deleted when its last use is subsumed below. 2112 assert(alock->outcnt() == 2 && 2113 _callprojs.fallthrough_proj != nullptr && 2114 _callprojs.fallthrough_memproj != nullptr, 2115 "Unexpected projections from Lock/Unlock"); 2116 2117 Node* fallthroughproj = _callprojs.fallthrough_proj; 2118 Node* memproj_fallthrough = _callprojs.fallthrough_memproj; 2119 2120 // The memory projection from a lock/unlock is RawMem 2121 // The input to a Lock is merged memory, so extract its RawMem input 2122 // (unless the MergeMem has been optimized away.) 2123 if (alock->is_Lock()) { 2124 // Seach for MemBarAcquireLock node and delete it also. 2125 MemBarNode* membar = fallthroughproj->unique_ctrl_out()->as_MemBar(); 2126 assert(membar != nullptr && membar->Opcode() == Op_MemBarAcquireLock, ""); 2127 Node* ctrlproj = membar->proj_out(TypeFunc::Control); 2128 Node* memproj = membar->proj_out(TypeFunc::Memory); 2129 _igvn.replace_node(ctrlproj, fallthroughproj); 2130 _igvn.replace_node(memproj, memproj_fallthrough); 2131 2132 // Delete FastLock node also if this Lock node is unique user 2133 // (a loop peeling may clone a Lock node). 2134 Node* flock = alock->as_Lock()->fastlock_node(); 2135 if (flock->outcnt() == 1) { 2136 assert(flock->unique_out() == alock, "sanity"); 2137 _igvn.replace_node(flock, top()); 2138 } 2139 } 2140 2141 // Seach for MemBarReleaseLock node and delete it also. 2142 if (alock->is_Unlock() && ctrl->is_Proj() && ctrl->in(0)->is_MemBar()) { 2143 MemBarNode* membar = ctrl->in(0)->as_MemBar(); 2144 assert(membar->Opcode() == Op_MemBarReleaseLock && 2145 mem->is_Proj() && membar == mem->in(0), ""); 2146 _igvn.replace_node(fallthroughproj, ctrl); 2147 _igvn.replace_node(memproj_fallthrough, mem); 2148 fallthroughproj = ctrl; 2149 memproj_fallthrough = mem; 2150 ctrl = membar->in(TypeFunc::Control); 2151 mem = membar->in(TypeFunc::Memory); 2152 } 2153 2154 _igvn.replace_node(fallthroughproj, ctrl); 2155 _igvn.replace_node(memproj_fallthrough, mem); 2156 return true; 2157 } 2158 2159 2160 //------------------------------expand_lock_node---------------------- 2161 void PhaseMacroExpand::expand_lock_node(LockNode *lock) { 2162 2163 Node* ctrl = lock->in(TypeFunc::Control); 2164 Node* mem = lock->in(TypeFunc::Memory); 2165 Node* obj = lock->obj_node(); 2166 Node* box = lock->box_node(); 2167 Node* flock = lock->fastlock_node(); 2168 2169 assert(!box->as_BoxLock()->is_eliminated(), "sanity"); 2170 2171 // Make the merge point 2172 Node *region; 2173 Node *mem_phi; 2174 Node *slow_path; 2175 2176 if (UseOptoBiasInlining) { 2177 /* 2178 * See the full description in MacroAssembler::biased_locking_enter(). 2179 * 2180 * if( (mark_word & biased_lock_mask) == biased_lock_pattern ) { 2181 * // The object is biased. 2182 * proto_node = klass->prototype_header; 2183 * o_node = thread | proto_node; 2184 * x_node = o_node ^ mark_word; 2185 * if( (x_node & ~age_mask) == 0 ) { // Biased to the current thread ? 2186 * // Done. 2187 * } else { 2188 * if( (x_node & biased_lock_mask) != 0 ) { 2189 * // The klass's prototype header is no longer biased. 2190 * cas(&mark_word, mark_word, proto_node) 2191 * goto cas_lock; 2192 * } else { 2193 * // The klass's prototype header is still biased. 2194 * if( (x_node & epoch_mask) != 0 ) { // Expired epoch? 2195 * old = mark_word; 2196 * new = o_node; 2197 * } else { 2198 * // Different thread or anonymous biased. 2199 * old = mark_word & (epoch_mask | age_mask | biased_lock_mask); 2200 * new = thread | old; 2201 * } 2202 * // Try to rebias. 2203 * if( cas(&mark_word, old, new) == 0 ) { 2204 * // Done. 2205 * } else { 2206 * goto slow_path; // Failed. 2207 * } 2208 * } 2209 * } 2210 * } else { 2211 * // The object is not biased. 2212 * cas_lock: 2213 * if( FastLock(obj) == 0 ) { 2214 * // Done. 2215 * } else { 2216 * slow_path: 2217 * OptoRuntime::complete_monitor_locking_Java(obj); 2218 * } 2219 * } 2220 */ 2221 2222 region = new RegionNode(5); 2223 // create a Phi for the memory state 2224 mem_phi = new PhiNode( region, Type::MEMORY, TypeRawPtr::BOTTOM); 2225 2226 Node* fast_lock_region = new RegionNode(3); 2227 Node* fast_lock_mem_phi = new PhiNode( fast_lock_region, Type::MEMORY, TypeRawPtr::BOTTOM); 2228 2229 // First, check mark word for the biased lock pattern. 2230 Node* mark_node = make_load(ctrl, mem, obj, oopDesc::mark_offset_in_bytes(), TypeX_X, TypeX_X->basic_type()); 2231 2232 // Get fast path - mark word has the biased lock pattern. 2233 ctrl = opt_bits_test(ctrl, fast_lock_region, 1, mark_node, 2234 markWord::biased_lock_mask_in_place, 2235 markWord::biased_lock_pattern, true); 2236 // fast_lock_region->in(1) is set to slow path. 2237 fast_lock_mem_phi->init_req(1, mem); 2238 2239 // Now check that the lock is biased to the current thread and has 2240 // the same epoch and bias as Klass::_prototype_header. 2241 2242 // Special-case a fresh allocation to avoid building nodes: 2243 Node* klass_node = AllocateNode::Ideal_klass(obj, &_igvn); 2244 if (klass_node == NULL) { 2245 Node* k_adr = basic_plus_adr(obj, oopDesc::klass_offset_in_bytes()); 2246 klass_node = transform_later(LoadKlassNode::make(_igvn, NULL, mem, k_adr, _igvn.type(k_adr)->is_ptr())); 2247 #ifdef _LP64 2248 if (UseCompressedClassPointers && klass_node->is_DecodeNKlass()) { 2249 assert(klass_node->in(1)->Opcode() == Op_LoadNKlass, "sanity"); 2250 klass_node->in(1)->init_req(0, ctrl); 2251 } else 2252 #endif 2253 klass_node->init_req(0, ctrl); 2254 } 2255 Node *proto_node = make_load(ctrl, mem, klass_node, in_bytes(Klass::prototype_header_offset()), TypeX_X, TypeX_X->basic_type()); 2256 2257 Node* thread = transform_later(new ThreadLocalNode()); 2258 Node* cast_thread = transform_later(new CastP2XNode(ctrl, thread)); 2259 Node* o_node = transform_later(new OrXNode(cast_thread, proto_node)); 2260 Node* x_node = transform_later(new XorXNode(o_node, mark_node)); 2261 2262 // Get slow path - mark word does NOT match the value. 2263 STATIC_ASSERT(markWord::age_mask_in_place <= INT_MAX); 2264 Node* not_biased_ctrl = opt_bits_test(ctrl, region, 3, x_node, 2265 (~(int)markWord::age_mask_in_place), 0); 2266 // region->in(3) is set to fast path - the object is biased to the current thread. 2267 mem_phi->init_req(3, mem); 2268 2269 2270 // Mark word does NOT match the value (thread | Klass::_prototype_header). 2271 2272 2273 // First, check biased pattern. 2274 // Get fast path - _prototype_header has the same biased lock pattern. 2275 ctrl = opt_bits_test(not_biased_ctrl, fast_lock_region, 2, x_node, 2276 markWord::biased_lock_mask_in_place, 0, true); 2277 2278 not_biased_ctrl = fast_lock_region->in(2); // Slow path 2279 // fast_lock_region->in(2) - the prototype header is no longer biased 2280 // and we have to revoke the bias on this object. 2281 // We are going to try to reset the mark of this object to the prototype 2282 // value and fall through to the CAS-based locking scheme. 2283 Node* adr = basic_plus_adr(obj, oopDesc::mark_offset_in_bytes()); 2284 Node* cas = new StoreXConditionalNode(not_biased_ctrl, mem, adr, 2285 proto_node, mark_node); 2286 transform_later(cas); 2287 Node* proj = transform_later(new SCMemProjNode(cas)); 2288 fast_lock_mem_phi->init_req(2, proj); 2289 2290 2291 // Second, check epoch bits. 2292 Node* rebiased_region = new RegionNode(3); 2293 Node* old_phi = new PhiNode( rebiased_region, TypeX_X); 2294 Node* new_phi = new PhiNode( rebiased_region, TypeX_X); 2295 2296 // Get slow path - mark word does NOT match epoch bits. 2297 Node* epoch_ctrl = opt_bits_test(ctrl, rebiased_region, 1, x_node, 2298 markWord::epoch_mask_in_place, 0); 2299 // The epoch of the current bias is not valid, attempt to rebias the object 2300 // toward the current thread. 2301 rebiased_region->init_req(2, epoch_ctrl); 2302 old_phi->init_req(2, mark_node); 2303 new_phi->init_req(2, o_node); 2304 2305 // rebiased_region->in(1) is set to fast path. 2306 // The epoch of the current bias is still valid but we know 2307 // nothing about the owner; it might be set or it might be clear. 2308 Node* cmask = MakeConX(markWord::biased_lock_mask_in_place | 2309 markWord::age_mask_in_place | 2310 markWord::epoch_mask_in_place); 2311 Node* old = transform_later(new AndXNode(mark_node, cmask)); 2312 cast_thread = transform_later(new CastP2XNode(ctrl, thread)); 2313 Node* new_mark = transform_later(new OrXNode(cast_thread, old)); 2314 old_phi->init_req(1, old); 2315 new_phi->init_req(1, new_mark); 2316 2317 transform_later(rebiased_region); 2318 transform_later(old_phi); 2319 transform_later(new_phi); 2320 2321 // Try to acquire the bias of the object using an atomic operation. 2322 // If this fails we will go in to the runtime to revoke the object's bias. 2323 cas = new StoreXConditionalNode(rebiased_region, mem, adr, new_phi, old_phi); 2324 transform_later(cas); 2325 proj = transform_later(new SCMemProjNode(cas)); 2326 2327 // Get slow path - Failed to CAS. 2328 not_biased_ctrl = opt_bits_test(rebiased_region, region, 4, cas, 0, 0); 2329 mem_phi->init_req(4, proj); 2330 // region->in(4) is set to fast path - the object is rebiased to the current thread. 2331 2332 // Failed to CAS. 2333 slow_path = new RegionNode(3); 2334 Node *slow_mem = new PhiNode( slow_path, Type::MEMORY, TypeRawPtr::BOTTOM); 2335 2336 slow_path->init_req(1, not_biased_ctrl); // Capture slow-control 2337 slow_mem->init_req(1, proj); 2338 2339 // Call CAS-based locking scheme (FastLock node). 2340 2341 transform_later(fast_lock_region); 2342 transform_later(fast_lock_mem_phi); 2343 2344 // Get slow path - FastLock failed to lock the object. 2345 ctrl = opt_bits_test(fast_lock_region, region, 2, flock, 0, 0); 2346 mem_phi->init_req(2, fast_lock_mem_phi); 2347 // region->in(2) is set to fast path - the object is locked to the current thread. 2348 2349 slow_path->init_req(2, ctrl); // Capture slow-control 2350 slow_mem->init_req(2, fast_lock_mem_phi); 2351 2352 transform_later(slow_path); 2353 transform_later(slow_mem); 2354 // Reset lock's memory edge. 2355 lock->set_req(TypeFunc::Memory, slow_mem); 2356 2357 } else { 2358 region = new RegionNode(3); 2359 // create a Phi for the memory state 2360 mem_phi = new PhiNode( region, Type::MEMORY, TypeRawPtr::BOTTOM); 2361 2362 // Optimize test; set region slot 2 2363 slow_path = opt_bits_test(ctrl, region, 2, flock, 0, 0); 2364 mem_phi->init_req(2, mem); 2365 } 2366 2367 // Make slow path call 2368 CallNode *call = make_slow_call((CallNode *) lock, OptoRuntime::complete_monitor_enter_Type(), 2369 OptoRuntime::complete_monitor_locking_Java(), nullptr, slow_path, 2370 obj, box, nullptr); 2371 2372 call->extract_projections(&_callprojs, false /*separate_io_proj*/, false /*do_asserts*/); 2373 2374 // Slow path can only throw asynchronous exceptions, which are always 2375 // de-opted. So the compiler thinks the slow-call can never throw an 2376 // exception. If it DOES throw an exception we would need the debug 2377 // info removed first (since if it throws there is no monitor). 2378 assert(_callprojs.fallthrough_ioproj == nullptr && _callprojs.catchall_ioproj == nullptr && 2379 _callprojs.catchall_memproj == nullptr && _callprojs.catchall_catchproj == nullptr, "Unexpected projection from Lock"); 2380 2381 // Capture slow path 2382 // disconnect fall-through projection from call and create a new one 2383 // hook up users of fall-through projection to region 2384 Node *slow_ctrl = _callprojs.fallthrough_proj->clone(); 2385 transform_later(slow_ctrl); 2386 _igvn.hash_delete(_callprojs.fallthrough_proj); 2387 _callprojs.fallthrough_proj->disconnect_inputs(C); 2388 region->init_req(1, slow_ctrl); 2389 // region inputs are now complete 2390 transform_later(region); 2391 _igvn.replace_node(_callprojs.fallthrough_proj, region); 2392 2393 Node *memproj = transform_later(new ProjNode(call, TypeFunc::Memory)); 2394 mem_phi->init_req(1, memproj ); 2395 transform_later(mem_phi); 2396 _igvn.replace_node(_callprojs.fallthrough_memproj, mem_phi); 2397 } 2398 2399 //------------------------------expand_unlock_node---------------------- 2400 void PhaseMacroExpand::expand_unlock_node(UnlockNode *unlock) { 2401 2402 Node* ctrl = unlock->in(TypeFunc::Control); 2403 Node* mem = unlock->in(TypeFunc::Memory); 2404 Node* obj = unlock->obj_node(); 2405 Node* box = unlock->box_node(); 2406 2407 assert(!box->as_BoxLock()->is_eliminated(), "sanity"); 2408 2409 // No need for a null check on unlock 2410 2411 // Make the merge point 2412 Node *region; 2413 Node *mem_phi; 2414 2415 if (UseOptoBiasInlining) { 2416 // Check for biased locking unlock case, which is a no-op. 2417 // See the full description in MacroAssembler::biased_locking_exit(). 2418 region = new RegionNode(4); 2419 // create a Phi for the memory state 2420 mem_phi = new PhiNode( region, Type::MEMORY, TypeRawPtr::BOTTOM); 2421 mem_phi->init_req(3, mem); 2422 2423 Node* mark_node = make_load(ctrl, mem, obj, oopDesc::mark_offset_in_bytes(), TypeX_X, TypeX_X->basic_type()); 2424 ctrl = opt_bits_test(ctrl, region, 3, mark_node, 2425 markWord::biased_lock_mask_in_place, 2426 markWord::biased_lock_pattern); 2427 } else { 2428 region = new RegionNode(3); 2429 // create a Phi for the memory state 2430 mem_phi = new PhiNode( region, Type::MEMORY, TypeRawPtr::BOTTOM); 2431 } 2432 2433 FastUnlockNode *funlock = new FastUnlockNode( ctrl, obj, box ); 2434 funlock = transform_later( funlock )->as_FastUnlock(); 2435 // Optimize test; set region slot 2 2436 Node *slow_path = opt_bits_test(ctrl, region, 2, funlock, 0, 0); 2437 Node *thread = transform_later(new ThreadLocalNode()); 2438 2439 CallNode *call = make_slow_call((CallNode *) unlock, OptoRuntime::complete_monitor_exit_Type(), 2440 CAST_FROM_FN_PTR(address, SharedRuntime::complete_monitor_unlocking_C), 2441 "complete_monitor_unlocking_C", slow_path, obj, box, thread); 2442 2443 call->extract_projections(&_callprojs, false /*separate_io_proj*/, false /*do_asserts*/); 2444 assert(_callprojs.fallthrough_ioproj == nullptr && _callprojs.catchall_ioproj == nullptr && 2445 _callprojs.catchall_memproj == nullptr && _callprojs.catchall_catchproj == nullptr, "Unexpected projection from Lock"); 2446 2447 // No exceptions for unlocking 2448 // Capture slow path 2449 // disconnect fall-through projection from call and create a new one 2450 // hook up users of fall-through projection to region 2451 Node *slow_ctrl = _callprojs.fallthrough_proj->clone(); 2452 transform_later(slow_ctrl); 2453 _igvn.hash_delete(_callprojs.fallthrough_proj); 2454 _callprojs.fallthrough_proj->disconnect_inputs(C); 2455 region->init_req(1, slow_ctrl); 2456 // region inputs are now complete 2457 transform_later(region); 2458 _igvn.replace_node(_callprojs.fallthrough_proj, region); 2459 2460 Node *memproj = transform_later(new ProjNode(call, TypeFunc::Memory) ); 2461 mem_phi->init_req(1, memproj ); 2462 mem_phi->init_req(2, mem); 2463 transform_later(mem_phi); 2464 _igvn.replace_node(_callprojs.fallthrough_memproj, mem_phi); 2465 } 2466 2467 void PhaseMacroExpand::expand_subtypecheck_node(SubTypeCheckNode *check) { 2468 assert(check->in(SubTypeCheckNode::Control) == nullptr, "should be pinned"); 2469 Node* bol = check->unique_out(); 2470 Node* obj_or_subklass = check->in(SubTypeCheckNode::ObjOrSubKlass); 2471 Node* superklass = check->in(SubTypeCheckNode::SuperKlass); 2472 assert(bol->is_Bool() && bol->as_Bool()->_test._test == BoolTest::ne, "unexpected bool node"); 2473 2474 for (DUIterator_Last imin, i = bol->last_outs(imin); i >= imin; --i) { 2475 Node* iff = bol->last_out(i); 2476 assert(iff->is_If(), "where's the if?"); 2477 2478 if (iff->in(0)->is_top()) { 2479 _igvn.replace_input_of(iff, 1, C->top()); 2480 continue; 2481 } 2482 2483 Node* iftrue = iff->as_If()->proj_out(1); 2484 Node* iffalse = iff->as_If()->proj_out(0); 2485 Node* ctrl = iff->in(0); 2486 2487 Node* subklass = nullptr; 2488 if (_igvn.type(obj_or_subklass)->isa_klassptr()) { 2489 subklass = obj_or_subklass; 2490 } else { 2491 Node* k_adr = basic_plus_adr(obj_or_subklass, oopDesc::klass_offset_in_bytes()); 2492 subklass = _igvn.transform(LoadKlassNode::make(_igvn, nullptr, C->immutable_memory(), k_adr, TypeInstPtr::KLASS)); 2493 } 2494 2495 Node* not_subtype_ctrl = Phase::gen_subtype_check(subklass, superklass, &ctrl, nullptr, _igvn); 2496 2497 _igvn.replace_input_of(iff, 0, C->top()); 2498 _igvn.replace_node(iftrue, not_subtype_ctrl); 2499 _igvn.replace_node(iffalse, ctrl); 2500 } 2501 _igvn.replace_node(check, C->top()); 2502 } 2503 2504 //---------------------------eliminate_macro_nodes---------------------- 2505 // Eliminate scalar replaced allocations and associated locks. 2506 void PhaseMacroExpand::eliminate_macro_nodes() { 2507 if (C->macro_count() == 0) 2508 return; 2509 2510 // Before elimination may re-mark (change to Nested or NonEscObj) 2511 // all associated (same box and obj) lock and unlock nodes. 2512 int cnt = C->macro_count(); 2513 for (int i=0; i < cnt; i++) { 2514 Node *n = C->macro_node(i); 2515 if (n->is_AbstractLock()) { // Lock and Unlock nodes 2516 mark_eliminated_locking_nodes(n->as_AbstractLock()); 2517 } 2518 } 2519 // Re-marking may break consistency of Coarsened locks. 2520 if (!C->coarsened_locks_consistent()) { 2521 return; // recompile without Coarsened locks if broken 2522 } 2523 2524 // First, attempt to eliminate locks 2525 bool progress = true; 2526 while (progress) { 2527 progress = false; 2528 for (int i = C->macro_count(); i > 0; i = MIN2(i - 1, C->macro_count())) { // more than 1 element can be eliminated at once 2529 Node* n = C->macro_node(i - 1); 2530 bool success = false; 2531 DEBUG_ONLY(int old_macro_count = C->macro_count();) 2532 if (n->is_AbstractLock()) { 2533 success = eliminate_locking_node(n->as_AbstractLock()); 2534 } 2535 assert(success == (C->macro_count() < old_macro_count), "elimination reduces macro count"); 2536 progress = progress || success; 2537 } 2538 } 2539 // Next, attempt to eliminate allocations 2540 _has_locks = false; 2541 progress = true; 2542 while (progress) { 2543 progress = false; 2544 for (int i = C->macro_count(); i > 0; i = MIN2(i - 1, C->macro_count())) { // more than 1 element can be eliminated at once 2545 Node* n = C->macro_node(i - 1); 2546 bool success = false; 2547 DEBUG_ONLY(int old_macro_count = C->macro_count();) 2548 switch (n->class_id()) { 2549 case Node::Class_Allocate: 2550 case Node::Class_AllocateArray: 2551 success = eliminate_allocate_node(n->as_Allocate()); 2552 break; 2553 case Node::Class_CallStaticJava: 2554 success = eliminate_boxing_node(n->as_CallStaticJava()); 2555 break; 2556 case Node::Class_Lock: 2557 case Node::Class_Unlock: 2558 assert(!n->as_AbstractLock()->is_eliminated(), "sanity"); 2559 _has_locks = true; 2560 break; 2561 case Node::Class_ArrayCopy: 2562 break; 2563 case Node::Class_OuterStripMinedLoop: 2564 break; 2565 case Node::Class_SubTypeCheck: 2566 break; 2567 case Node::Class_Opaque1: 2568 break; 2569 default: 2570 assert(n->Opcode() == Op_LoopLimit || 2571 n->Opcode() == Op_Opaque2 || 2572 n->Opcode() == Op_Opaque3 || 2573 n->Opcode() == Op_Opaque4 || 2574 BarrierSet::barrier_set()->barrier_set_c2()->is_gc_barrier_node(n), 2575 "unknown node type in macro list"); 2576 } 2577 assert(success == (C->macro_count() < old_macro_count), "elimination reduces macro count"); 2578 progress = progress || success; 2579 } 2580 } 2581 } 2582 2583 //------------------------------expand_macro_nodes---------------------- 2584 // Returns true if a failure occurred. 2585 bool PhaseMacroExpand::expand_macro_nodes() { 2586 // Last attempt to eliminate macro nodes. 2587 eliminate_macro_nodes(); 2588 if (C->failing()) return true; 2589 2590 // Eliminate Opaque and LoopLimit nodes. Do it after all loop optimizations. 2591 bool progress = true; 2592 while (progress) { 2593 progress = false; 2594 for (int i = C->macro_count(); i > 0; i--) { 2595 Node* n = C->macro_node(i-1); 2596 bool success = false; 2597 DEBUG_ONLY(int old_macro_count = C->macro_count();) 2598 if (n->Opcode() == Op_LoopLimit) { 2599 // Remove it from macro list and put on IGVN worklist to optimize. 2600 C->remove_macro_node(n); 2601 _igvn._worklist.push(n); 2602 success = true; 2603 } else if (n->Opcode() == Op_CallStaticJava) { 2604 // Remove it from macro list and put on IGVN worklist to optimize. 2605 C->remove_macro_node(n); 2606 _igvn._worklist.push(n); 2607 success = true; 2608 } else if (n->is_Opaque1() || n->Opcode() == Op_Opaque2) { 2609 _igvn.replace_node(n, n->in(1)); 2610 success = true; 2611 #if INCLUDE_RTM_OPT 2612 } else if ((n->Opcode() == Op_Opaque3) && ((Opaque3Node*)n)->rtm_opt()) { 2613 assert(C->profile_rtm(), "should be used only in rtm deoptimization code"); 2614 assert((n->outcnt() == 1) && n->unique_out()->is_Cmp(), ""); 2615 Node* cmp = n->unique_out(); 2616 #ifdef ASSERT 2617 // Validate graph. 2618 assert((cmp->outcnt() == 1) && cmp->unique_out()->is_Bool(), ""); 2619 BoolNode* bol = cmp->unique_out()->as_Bool(); 2620 assert((bol->outcnt() == 1) && bol->unique_out()->is_If() && 2621 (bol->_test._test == BoolTest::ne), ""); 2622 IfNode* ifn = bol->unique_out()->as_If(); 2623 assert((ifn->outcnt() == 2) && 2624 ifn->proj_out(1)->is_uncommon_trap_proj(Deoptimization::Reason_rtm_state_change) != nullptr, ""); 2625 #endif 2626 Node* repl = n->in(1); 2627 if (!_has_locks) { 2628 // Remove RTM state check if there are no locks in the code. 2629 // Replace input to compare the same value. 2630 repl = (cmp->in(1) == n) ? cmp->in(2) : cmp->in(1); 2631 } 2632 _igvn.replace_node(n, repl); 2633 success = true; 2634 #endif 2635 } else if (n->Opcode() == Op_Opaque4) { 2636 // With Opaque4 nodes, the expectation is that the test of input 1 2637 // is always equal to the constant value of input 2. So we can 2638 // remove the Opaque4 and replace it by input 2. In debug builds, 2639 // leave the non constant test in instead to sanity check that it 2640 // never fails (if it does, that subgraph was constructed so, at 2641 // runtime, a Halt node is executed). 2642 #ifdef ASSERT 2643 _igvn.replace_node(n, n->in(1)); 2644 #else 2645 _igvn.replace_node(n, n->in(2)); 2646 #endif 2647 success = true; 2648 } else if (n->Opcode() == Op_OuterStripMinedLoop) { 2649 n->as_OuterStripMinedLoop()->adjust_strip_mined_loop(&_igvn); 2650 C->remove_macro_node(n); 2651 success = true; 2652 } 2653 assert(!success || (C->macro_count() == (old_macro_count - 1)), "elimination must have deleted one node from macro list"); 2654 progress = progress || success; 2655 } 2656 } 2657 2658 // Clean up the graph so we're less likely to hit the maximum node 2659 // limit 2660 _igvn.set_delay_transform(false); 2661 _igvn.optimize(); 2662 if (C->failing()) return true; 2663 _igvn.set_delay_transform(true); 2664 2665 2666 // Because we run IGVN after each expansion, some macro nodes may go 2667 // dead and be removed from the list as we iterate over it. Move 2668 // Allocate nodes (processed in a second pass) at the beginning of 2669 // the list and then iterate from the last element of the list until 2670 // an Allocate node is seen. This is robust to random deletion in 2671 // the list due to nodes going dead. 2672 C->sort_macro_nodes(); 2673 2674 // expand arraycopy "macro" nodes first 2675 // For ReduceBulkZeroing, we must first process all arraycopy nodes 2676 // before the allocate nodes are expanded. 2677 while (C->macro_count() > 0) { 2678 int macro_count = C->macro_count(); 2679 Node * n = C->macro_node(macro_count-1); 2680 assert(n->is_macro(), "only macro nodes expected here"); 2681 if (_igvn.type(n) == Type::TOP || (n->in(0) != nullptr && n->in(0)->is_top())) { 2682 // node is unreachable, so don't try to expand it 2683 C->remove_macro_node(n); 2684 continue; 2685 } 2686 if (n->is_Allocate()) { 2687 break; 2688 } 2689 // Make sure expansion will not cause node limit to be exceeded. 2690 // Worst case is a macro node gets expanded into about 200 nodes. 2691 // Allow 50% more for optimization. 2692 if (C->check_node_count(300, "out of nodes before macro expansion")) { 2693 return true; 2694 } 2695 2696 DEBUG_ONLY(int old_macro_count = C->macro_count();) 2697 switch (n->class_id()) { 2698 case Node::Class_Lock: 2699 expand_lock_node(n->as_Lock()); 2700 break; 2701 case Node::Class_Unlock: 2702 expand_unlock_node(n->as_Unlock()); 2703 break; 2704 case Node::Class_ArrayCopy: 2705 expand_arraycopy_node(n->as_ArrayCopy()); 2706 break; 2707 case Node::Class_SubTypeCheck: 2708 expand_subtypecheck_node(n->as_SubTypeCheck()); 2709 break; 2710 default: 2711 assert(false, "unknown node type in macro list"); 2712 } 2713 assert(C->macro_count() == (old_macro_count - 1), "expansion must have deleted one node from macro list"); 2714 if (C->failing()) return true; 2715 2716 // Clean up the graph so we're less likely to hit the maximum node 2717 // limit 2718 _igvn.set_delay_transform(false); 2719 _igvn.optimize(); 2720 if (C->failing()) return true; 2721 _igvn.set_delay_transform(true); 2722 } 2723 2724 // All nodes except Allocate nodes are expanded now. There could be 2725 // new optimization opportunities (such as folding newly created 2726 // load from a just allocated object). Run IGVN. 2727 2728 // expand "macro" nodes 2729 // nodes are removed from the macro list as they are processed 2730 while (C->macro_count() > 0) { 2731 int macro_count = C->macro_count(); 2732 Node * n = C->macro_node(macro_count-1); 2733 assert(n->is_macro(), "only macro nodes expected here"); 2734 if (_igvn.type(n) == Type::TOP || (n->in(0) != nullptr && n->in(0)->is_top())) { 2735 // node is unreachable, so don't try to expand it 2736 C->remove_macro_node(n); 2737 continue; 2738 } 2739 // Make sure expansion will not cause node limit to be exceeded. 2740 // Worst case is a macro node gets expanded into about 200 nodes. 2741 // Allow 50% more for optimization. 2742 if (C->check_node_count(300, "out of nodes before macro expansion")) { 2743 return true; 2744 } 2745 switch (n->class_id()) { 2746 case Node::Class_Allocate: 2747 expand_allocate(n->as_Allocate()); 2748 break; 2749 case Node::Class_AllocateArray: 2750 expand_allocate_array(n->as_AllocateArray()); 2751 break; 2752 default: 2753 assert(false, "unknown node type in macro list"); 2754 } 2755 assert(C->macro_count() < macro_count, "must have deleted a node from macro list"); 2756 if (C->failing()) return true; 2757 2758 // Clean up the graph so we're less likely to hit the maximum node 2759 // limit 2760 _igvn.set_delay_transform(false); 2761 _igvn.optimize(); 2762 if (C->failing()) return true; 2763 _igvn.set_delay_transform(true); 2764 } 2765 2766 _igvn.set_delay_transform(false); 2767 return false; 2768 } --- EOF ---