1 /* 2 * Copyright (c) 2005, 2025, 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 "ci/ciFlatArrayKlass.hpp" 26 #include "ci/ciInstanceKlass.hpp" 27 #include "compiler/compileLog.hpp" 28 #include "gc/shared/collectedHeap.inline.hpp" 29 #include "gc/shared/tlab_globals.hpp" 30 #include "libadt/vectset.hpp" 31 #include "memory/universe.hpp" 32 #include "opto/addnode.hpp" 33 #include "opto/arraycopynode.hpp" 34 #include "opto/callnode.hpp" 35 #include "opto/castnode.hpp" 36 #include "opto/cfgnode.hpp" 37 #include "opto/compile.hpp" 38 #include "opto/convertnode.hpp" 39 #include "opto/graphKit.hpp" 40 #include "opto/inlinetypenode.hpp" 41 #include "opto/intrinsicnode.hpp" 42 #include "opto/locknode.hpp" 43 #include "opto/loopnode.hpp" 44 #include "opto/macro.hpp" 45 #include "opto/memnode.hpp" 46 #include "opto/narrowptrnode.hpp" 47 #include "opto/node.hpp" 48 #include "opto/opaquenode.hpp" 49 #include "opto/phaseX.hpp" 50 #include "opto/rootnode.hpp" 51 #include "opto/runtime.hpp" 52 #include "opto/subnode.hpp" 53 #include "opto/subtypenode.hpp" 54 #include "opto/type.hpp" 55 #include "prims/jvmtiExport.hpp" 56 #include "runtime/continuation.hpp" 57 #include "runtime/sharedRuntime.hpp" 58 #include "runtime/stubRoutines.hpp" 59 #include "utilities/globalDefinitions.hpp" 60 #include "utilities/macros.hpp" 61 #include "utilities/powerOfTwo.hpp" 62 #if INCLUDE_G1GC 63 #include "gc/g1/g1ThreadLocalData.hpp" 64 #endif // INCLUDE_G1GC 65 66 67 // 68 // Replace any references to "oldref" in inputs to "use" with "newref". 69 // Returns the number of replacements made. 70 // 71 int PhaseMacroExpand::replace_input(Node *use, Node *oldref, Node *newref) { 72 int nreplacements = 0; 73 uint req = use->req(); 74 for (uint j = 0; j < use->len(); j++) { 75 Node *uin = use->in(j); 76 if (uin == oldref) { 77 if (j < req) 78 use->set_req(j, newref); 79 else 80 use->set_prec(j, newref); 81 nreplacements++; 82 } else if (j >= req && uin == nullptr) { 83 break; 84 } 85 } 86 return nreplacements; 87 } 88 89 Node* PhaseMacroExpand::opt_bits_test(Node* ctrl, Node* region, int edge, Node* word, int mask, int bits, bool return_fast_path) { 90 Node* cmp; 91 if (mask != 0) { 92 Node* and_node = transform_later(new AndXNode(word, MakeConX(mask))); 93 cmp = transform_later(new CmpXNode(and_node, MakeConX(bits))); 94 } else { 95 cmp = word; 96 } 97 Node* bol = transform_later(new BoolNode(cmp, BoolTest::ne)); 98 IfNode* iff = new IfNode( ctrl, bol, PROB_MIN, COUNT_UNKNOWN ); 99 transform_later(iff); 100 101 // Fast path taken. 102 Node *fast_taken = transform_later(new IfFalseNode(iff)); 103 104 // Fast path not-taken, i.e. slow path 105 Node *slow_taken = transform_later(new IfTrueNode(iff)); 106 107 if (return_fast_path) { 108 region->init_req(edge, slow_taken); // Capture slow-control 109 return fast_taken; 110 } else { 111 region->init_req(edge, fast_taken); // Capture fast-control 112 return slow_taken; 113 } 114 } 115 116 //--------------------copy_predefined_input_for_runtime_call-------------------- 117 void PhaseMacroExpand::copy_predefined_input_for_runtime_call(Node * ctrl, CallNode* oldcall, CallNode* call) { 118 // Set fixed predefined input arguments 119 call->init_req( TypeFunc::Control, ctrl ); 120 call->init_req( TypeFunc::I_O , oldcall->in( TypeFunc::I_O) ); 121 call->init_req( TypeFunc::Memory , oldcall->in( TypeFunc::Memory ) ); // ????? 122 call->init_req( TypeFunc::ReturnAdr, oldcall->in( TypeFunc::ReturnAdr ) ); 123 call->init_req( TypeFunc::FramePtr, oldcall->in( TypeFunc::FramePtr ) ); 124 } 125 126 //------------------------------make_slow_call--------------------------------- 127 CallNode* PhaseMacroExpand::make_slow_call(CallNode *oldcall, const TypeFunc* slow_call_type, 128 address slow_call, const char* leaf_name, Node* slow_path, 129 Node* parm0, Node* parm1, Node* parm2) { 130 131 // Slow-path call 132 CallNode *call = leaf_name 133 ? (CallNode*)new CallLeafNode ( slow_call_type, slow_call, leaf_name, TypeRawPtr::BOTTOM ) 134 : (CallNode*)new CallStaticJavaNode( slow_call_type, slow_call, OptoRuntime::stub_name(slow_call), TypeRawPtr::BOTTOM ); 135 136 // Slow path call has no side-effects, uses few values 137 copy_predefined_input_for_runtime_call(slow_path, oldcall, call ); 138 if (parm0 != nullptr) call->init_req(TypeFunc::Parms+0, parm0); 139 if (parm1 != nullptr) call->init_req(TypeFunc::Parms+1, parm1); 140 if (parm2 != nullptr) call->init_req(TypeFunc::Parms+2, parm2); 141 call->copy_call_debug_info(&_igvn, oldcall); 142 call->set_cnt(PROB_UNLIKELY_MAG(4)); // Same effect as RC_UNCOMMON. 143 _igvn.replace_node(oldcall, call); 144 transform_later(call); 145 146 return call; 147 } 148 149 void PhaseMacroExpand::eliminate_gc_barrier(Node* p2x) { 150 BarrierSetC2 *bs = BarrierSet::barrier_set()->barrier_set_c2(); 151 bs->eliminate_gc_barrier(&_igvn, p2x); 152 #ifndef PRODUCT 153 if (PrintOptoStatistics) { 154 Atomic::inc(&PhaseMacroExpand::_GC_barriers_removed_counter); 155 } 156 #endif 157 } 158 159 // Search for a memory operation for the specified memory slice. 160 static Node *scan_mem_chain(Node *mem, int alias_idx, int offset, Node *start_mem, Node *alloc, PhaseGVN *phase) { 161 Node *orig_mem = mem; 162 Node *alloc_mem = alloc->as_Allocate()->proj_out_or_null(TypeFunc::Memory, /*io_use:*/false); 163 assert(alloc_mem != nullptr, "Allocation without a memory projection."); 164 const TypeOopPtr *tinst = phase->C->get_adr_type(alias_idx)->isa_oopptr(); 165 while (true) { 166 if (mem == alloc_mem || mem == start_mem ) { 167 return mem; // hit one of our sentinels 168 } else if (mem->is_MergeMem()) { 169 mem = mem->as_MergeMem()->memory_at(alias_idx); 170 } else if (mem->is_Proj() && mem->as_Proj()->_con == TypeFunc::Memory) { 171 Node *in = mem->in(0); 172 // we can safely skip over safepoints, calls, locks and membars because we 173 // already know that the object is safe to eliminate. 174 if (in->is_Initialize() && in->as_Initialize()->allocation() == alloc) { 175 return in; 176 } else if (in->is_Call()) { 177 CallNode *call = in->as_Call(); 178 if (call->may_modify(tinst, phase)) { 179 assert(call->is_ArrayCopy(), "ArrayCopy is the only call node that doesn't make allocation escape"); 180 if (call->as_ArrayCopy()->modifies(offset, offset, phase, false)) { 181 return in; 182 } 183 } 184 mem = in->in(TypeFunc::Memory); 185 } else if (in->is_MemBar()) { 186 ArrayCopyNode* ac = nullptr; 187 if (ArrayCopyNode::may_modify(tinst, in->as_MemBar(), phase, ac)) { 188 if (ac != nullptr) { 189 assert(ac->is_clonebasic(), "Only basic clone is a non escaping clone"); 190 return ac; 191 } 192 } 193 mem = in->in(TypeFunc::Memory); 194 } else { 195 #ifdef ASSERT 196 in->dump(); 197 mem->dump(); 198 assert(false, "unexpected projection"); 199 #endif 200 } 201 } else if (mem->is_Store()) { 202 const TypePtr* atype = mem->as_Store()->adr_type(); 203 int adr_idx = phase->C->get_alias_index(atype); 204 if (adr_idx == alias_idx) { 205 assert(atype->isa_oopptr(), "address type must be oopptr"); 206 int adr_offset = atype->flat_offset(); 207 uint adr_iid = atype->is_oopptr()->instance_id(); 208 // Array elements references have the same alias_idx 209 // but different offset and different instance_id. 210 if (adr_offset == offset && adr_iid == alloc->_idx) { 211 return mem; 212 } 213 } else { 214 assert(adr_idx == Compile::AliasIdxRaw, "address must match or be raw"); 215 } 216 mem = mem->in(MemNode::Memory); 217 } else if (mem->is_ClearArray()) { 218 if (!ClearArrayNode::step_through(&mem, alloc->_idx, phase)) { 219 // Can not bypass initialization of the instance 220 // we are looking. 221 DEBUG_ONLY(intptr_t offset;) 222 assert(alloc == AllocateNode::Ideal_allocation(mem->in(3), phase, offset), "sanity"); 223 InitializeNode* init = alloc->as_Allocate()->initialization(); 224 // We are looking for stored value, return Initialize node 225 // or memory edge from Allocate node. 226 if (init != nullptr) { 227 return init; 228 } else { 229 return alloc->in(TypeFunc::Memory); // It will produce zero value (see callers). 230 } 231 } 232 // Otherwise skip it (the call updated 'mem' value). 233 } else if (mem->Opcode() == Op_SCMemProj) { 234 mem = mem->in(0); 235 Node* adr = nullptr; 236 if (mem->is_LoadStore()) { 237 adr = mem->in(MemNode::Address); 238 } else { 239 assert(mem->Opcode() == Op_EncodeISOArray || 240 mem->Opcode() == Op_StrCompressedCopy, "sanity"); 241 adr = mem->in(3); // Destination array 242 } 243 const TypePtr* atype = adr->bottom_type()->is_ptr(); 244 int adr_idx = phase->C->get_alias_index(atype); 245 if (adr_idx == alias_idx) { 246 DEBUG_ONLY(mem->dump();) 247 assert(false, "Object is not scalar replaceable if a LoadStore node accesses its field"); 248 return nullptr; 249 } 250 mem = mem->in(MemNode::Memory); 251 } else if (mem->Opcode() == Op_StrInflatedCopy) { 252 Node* adr = mem->in(3); // Destination array 253 const TypePtr* atype = adr->bottom_type()->is_ptr(); 254 int adr_idx = phase->C->get_alias_index(atype); 255 if (adr_idx == alias_idx) { 256 DEBUG_ONLY(mem->dump();) 257 assert(false, "Object is not scalar replaceable if a StrInflatedCopy node accesses its field"); 258 return nullptr; 259 } 260 mem = mem->in(MemNode::Memory); 261 } else { 262 return mem; 263 } 264 assert(mem != orig_mem, "dead memory loop"); 265 } 266 } 267 268 // Generate loads from source of the arraycopy for fields of 269 // destination needed at a deoptimization point 270 Node* PhaseMacroExpand::make_arraycopy_load(ArrayCopyNode* ac, intptr_t offset, Node* ctl, Node* mem, BasicType ft, const Type *ftype, AllocateNode *alloc) { 271 BasicType bt = ft; 272 const Type *type = ftype; 273 if (ft == T_NARROWOOP) { 274 bt = T_OBJECT; 275 type = ftype->make_oopptr(); 276 } 277 Node* res = nullptr; 278 if (ac->is_clonebasic()) { 279 assert(ac->in(ArrayCopyNode::Src) != ac->in(ArrayCopyNode::Dest), "clone source equals destination"); 280 Node* base = ac->in(ArrayCopyNode::Src); 281 Node* adr = _igvn.transform(new AddPNode(base, base, _igvn.MakeConX(offset))); 282 const TypePtr* adr_type = _igvn.type(base)->is_ptr()->add_offset(offset); 283 MergeMemNode* mergemen = _igvn.transform(MergeMemNode::make(mem))->as_MergeMem(); 284 BarrierSetC2* bs = BarrierSet::barrier_set()->barrier_set_c2(); 285 res = ArrayCopyNode::load(bs, &_igvn, ctl, mergemen, adr, adr_type, type, bt); 286 } else { 287 if (ac->modifies(offset, offset, &_igvn, true)) { 288 assert(ac->in(ArrayCopyNode::Dest) == alloc->result_cast(), "arraycopy destination should be allocation's result"); 289 uint shift = exact_log2(type2aelembytes(bt)); 290 Node* src_pos = ac->in(ArrayCopyNode::SrcPos); 291 Node* dest_pos = ac->in(ArrayCopyNode::DestPos); 292 const TypeInt* src_pos_t = _igvn.type(src_pos)->is_int(); 293 const TypeInt* dest_pos_t = _igvn.type(dest_pos)->is_int(); 294 295 Node* adr = nullptr; 296 Node* base = ac->in(ArrayCopyNode::Src); 297 const TypeAryPtr* adr_type = _igvn.type(base)->is_aryptr(); 298 if (adr_type->is_flat()) { 299 shift = adr_type->flat_log_elem_size(); 300 } 301 if (src_pos_t->is_con() && dest_pos_t->is_con()) { 302 intptr_t off = ((src_pos_t->get_con() - dest_pos_t->get_con()) << shift) + offset; 303 adr = _igvn.transform(new AddPNode(base, base, _igvn.MakeConX(off))); 304 adr_type = _igvn.type(adr)->is_aryptr(); 305 assert(adr_type == _igvn.type(base)->is_aryptr()->add_field_offset_and_offset(off), "incorrect address type"); 306 if (ac->in(ArrayCopyNode::Src) == ac->in(ArrayCopyNode::Dest)) { 307 // Don't emit a new load from src if src == dst but try to get the value from memory instead 308 return value_from_mem(ac->in(TypeFunc::Memory), ctl, ft, ftype, adr_type, alloc); 309 } 310 } else { 311 if (ac->in(ArrayCopyNode::Src) == ac->in(ArrayCopyNode::Dest)) { 312 // Non constant offset in the array: we can't statically 313 // determine the value 314 return nullptr; 315 } 316 Node* diff = _igvn.transform(new SubINode(ac->in(ArrayCopyNode::SrcPos), ac->in(ArrayCopyNode::DestPos))); 317 #ifdef _LP64 318 diff = _igvn.transform(new ConvI2LNode(diff)); 319 #endif 320 diff = _igvn.transform(new LShiftXNode(diff, _igvn.intcon(shift))); 321 322 Node* off = _igvn.transform(new AddXNode(_igvn.MakeConX(offset), diff)); 323 adr = _igvn.transform(new AddPNode(base, base, off)); 324 // In the case of a flat inline type array, each field has its 325 // own slice so we need to extract the field being accessed from 326 // the address computation 327 adr_type = adr_type->add_field_offset_and_offset(offset)->add_offset(Type::OffsetBot)->is_aryptr(); 328 adr = _igvn.transform(new CastPPNode(ctl, adr, adr_type)); 329 } 330 MergeMemNode* mergemen = _igvn.transform(MergeMemNode::make(mem))->as_MergeMem(); 331 BarrierSetC2* bs = BarrierSet::barrier_set()->barrier_set_c2(); 332 res = ArrayCopyNode::load(bs, &_igvn, ctl, mergemen, adr, adr_type, type, bt); 333 } 334 } 335 if (res != nullptr) { 336 if (ftype->isa_narrowoop()) { 337 // PhaseMacroExpand::scalar_replacement adds DecodeN nodes 338 assert(res->isa_DecodeN(), "should be narrow oop"); 339 res = _igvn.transform(new EncodePNode(res, ftype)); 340 } 341 return res; 342 } 343 return nullptr; 344 } 345 346 // 347 // Given a Memory Phi, compute a value Phi containing the values from stores 348 // on the input paths. 349 // Note: this function is recursive, its depth is limited by the "level" argument 350 // Returns the computed Phi, or null if it cannot compute it. 351 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) { 352 assert(mem->is_Phi(), "sanity"); 353 int alias_idx = C->get_alias_index(adr_t); 354 int offset = adr_t->flat_offset(); 355 int instance_id = adr_t->instance_id(); 356 357 // Check if an appropriate value phi already exists. 358 Node* region = mem->in(0); 359 for (DUIterator_Fast kmax, k = region->fast_outs(kmax); k < kmax; k++) { 360 Node* phi = region->fast_out(k); 361 if (phi->is_Phi() && phi != mem && 362 phi->as_Phi()->is_same_inst_field(phi_type, (int)mem->_idx, instance_id, alias_idx, offset)) { 363 return phi; 364 } 365 } 366 // Check if an appropriate new value phi already exists. 367 Node* new_phi = value_phis->find(mem->_idx); 368 if (new_phi != nullptr) 369 return new_phi; 370 371 if (level <= 0) { 372 return nullptr; // Give up: phi tree too deep 373 } 374 Node *start_mem = C->start()->proj_out_or_null(TypeFunc::Memory); 375 Node *alloc_mem = alloc->proj_out_or_null(TypeFunc::Memory, /*io_use:*/false); 376 assert(alloc_mem != nullptr, "Allocation without a memory projection."); 377 378 uint length = mem->req(); 379 GrowableArray <Node *> values(length, length, nullptr); 380 381 // create a new Phi for the value 382 PhiNode *phi = new PhiNode(mem->in(0), phi_type, nullptr, mem->_idx, instance_id, alias_idx, offset); 383 transform_later(phi); 384 value_phis->push(phi, mem->_idx); 385 386 for (uint j = 1; j < length; j++) { 387 Node *in = mem->in(j); 388 if (in == nullptr || in->is_top()) { 389 values.at_put(j, in); 390 } else { 391 Node *val = scan_mem_chain(in, alias_idx, offset, start_mem, alloc, &_igvn); 392 if (val == start_mem || val == alloc_mem) { 393 // hit a sentinel, return appropriate value 394 Node* init_value = alloc->in(AllocateNode::InitValue); 395 if (init_value != nullptr) { 396 if (val == start_mem) { 397 // TODO 8350865 Scalar replacement does not work well for flat arrays. 398 // Somehow we ended up with root mem and therefore walked past the alloc. Fix this. Triggered by TestGenerated::test15 399 // Don't we need field_value_by_offset? 400 return nullptr; 401 } 402 values.at_put(j, init_value); 403 } else { 404 assert(alloc->in(AllocateNode::RawInitValue) == nullptr, "init value may not be null"); 405 values.at_put(j, _igvn.zerocon(ft)); 406 } 407 continue; 408 } 409 if (val->is_Initialize()) { 410 val = val->as_Initialize()->find_captured_store(offset, type2aelembytes(ft), &_igvn); 411 } 412 if (val == nullptr) { 413 return nullptr; // can't find a value on this path 414 } 415 if (val == mem) { 416 values.at_put(j, mem); 417 } else if (val->is_Store()) { 418 Node* n = val->in(MemNode::ValueIn); 419 BarrierSetC2* bs = BarrierSet::barrier_set()->barrier_set_c2(); 420 n = bs->step_over_gc_barrier(n); 421 if (is_subword_type(ft)) { 422 n = Compile::narrow_value(ft, n, phi_type, &_igvn, true); 423 } 424 values.at_put(j, n); 425 } else if (val->is_Proj() && val->in(0) == alloc) { 426 Node* init_value = alloc->in(AllocateNode::InitValue); 427 if (init_value != nullptr) { 428 // TODO 8350865 Scalar replacement does not work well for flat arrays. 429 // Is this correct for non-all-zero init values? Don't we need field_value_by_offset? 430 values.at_put(j, init_value); 431 } else { 432 assert(alloc->in(AllocateNode::RawInitValue) == nullptr, "init value may not be null"); 433 values.at_put(j, _igvn.zerocon(ft)); 434 } 435 } else if (val->is_Phi()) { 436 val = value_from_mem_phi(val, ft, phi_type, adr_t, alloc, value_phis, level-1); 437 if (val == nullptr) { 438 return nullptr; 439 } 440 values.at_put(j, val); 441 } else if (val->Opcode() == Op_SCMemProj) { 442 assert(val->in(0)->is_LoadStore() || 443 val->in(0)->Opcode() == Op_EncodeISOArray || 444 val->in(0)->Opcode() == Op_StrCompressedCopy, "sanity"); 445 assert(false, "Object is not scalar replaceable if a LoadStore node accesses its field"); 446 return nullptr; 447 } else if (val->is_ArrayCopy()) { 448 Node* res = make_arraycopy_load(val->as_ArrayCopy(), offset, val->in(0), val->in(TypeFunc::Memory), ft, phi_type, alloc); 449 if (res == nullptr) { 450 return nullptr; 451 } 452 values.at_put(j, res); 453 } else if (val->is_top()) { 454 // This indicates that this path into the phi is dead. Top will eventually also propagate into the Region. 455 // IGVN will clean this up later. 456 values.at_put(j, val); 457 } else { 458 DEBUG_ONLY( val->dump(); ) 459 assert(false, "unknown node on this path"); 460 return nullptr; // unknown node on this path 461 } 462 } 463 } 464 // Set Phi's inputs 465 for (uint j = 1; j < length; j++) { 466 if (values.at(j) == mem) { 467 phi->init_req(j, phi); 468 } else { 469 phi->init_req(j, values.at(j)); 470 } 471 } 472 return phi; 473 } 474 475 // Search the last value stored into the object's field. 476 Node *PhaseMacroExpand::value_from_mem(Node *sfpt_mem, Node *sfpt_ctl, BasicType ft, const Type *ftype, const TypeOopPtr *adr_t, AllocateNode *alloc) { 477 assert(adr_t->is_known_instance_field(), "instance required"); 478 int instance_id = adr_t->instance_id(); 479 assert((uint)instance_id == alloc->_idx, "wrong allocation"); 480 481 int alias_idx = C->get_alias_index(adr_t); 482 int offset = adr_t->flat_offset(); 483 Node *start_mem = C->start()->proj_out_or_null(TypeFunc::Memory); 484 Node *alloc_mem = alloc->proj_out_or_null(TypeFunc::Memory, /*io_use:*/false); 485 assert(alloc_mem != nullptr, "Allocation without a memory projection."); 486 VectorSet visited; 487 488 bool done = sfpt_mem == alloc_mem; 489 Node *mem = sfpt_mem; 490 while (!done) { 491 if (visited.test_set(mem->_idx)) { 492 return nullptr; // found a loop, give up 493 } 494 mem = scan_mem_chain(mem, alias_idx, offset, start_mem, alloc, &_igvn); 495 if (mem == start_mem || mem == alloc_mem) { 496 done = true; // hit a sentinel, return appropriate 0 value 497 } else if (mem->is_Initialize()) { 498 mem = mem->as_Initialize()->find_captured_store(offset, type2aelembytes(ft), &_igvn); 499 if (mem == nullptr) { 500 done = true; // Something went wrong. 501 } else if (mem->is_Store()) { 502 const TypePtr* atype = mem->as_Store()->adr_type(); 503 assert(C->get_alias_index(atype) == Compile::AliasIdxRaw, "store is correct memory slice"); 504 done = true; 505 } 506 } else if (mem->is_Store()) { 507 const TypeOopPtr* atype = mem->as_Store()->adr_type()->isa_oopptr(); 508 assert(atype != nullptr, "address type must be oopptr"); 509 assert(C->get_alias_index(atype) == alias_idx && 510 atype->is_known_instance_field() && atype->flat_offset() == offset && 511 atype->instance_id() == instance_id, "store is correct memory slice"); 512 done = true; 513 } else if (mem->is_Phi()) { 514 // try to find a phi's unique input 515 Node *unique_input = nullptr; 516 Node *top = C->top(); 517 for (uint i = 1; i < mem->req(); i++) { 518 Node *n = scan_mem_chain(mem->in(i), alias_idx, offset, start_mem, alloc, &_igvn); 519 if (n == nullptr || n == top || n == mem) { 520 continue; 521 } else if (unique_input == nullptr) { 522 unique_input = n; 523 } else if (unique_input != n) { 524 unique_input = top; 525 break; 526 } 527 } 528 if (unique_input != nullptr && unique_input != top) { 529 mem = unique_input; 530 } else { 531 done = true; 532 } 533 } else if (mem->is_ArrayCopy()) { 534 done = true; 535 } else { 536 DEBUG_ONLY( mem->dump(); ) 537 assert(false, "unexpected node"); 538 } 539 } 540 if (mem != nullptr) { 541 if (mem == start_mem || mem == alloc_mem) { 542 // hit a sentinel, return appropriate value 543 Node* init_value = alloc->in(AllocateNode::InitValue); 544 if (init_value != nullptr) { 545 if (adr_t->is_flat()) { 546 if (init_value->is_EncodeP()) { 547 init_value = init_value->in(1); 548 } 549 assert(adr_t->is_aryptr()->field_offset().get() != Type::OffsetBot, "Unknown offset"); 550 offset = adr_t->is_aryptr()->field_offset().get() + init_value->bottom_type()->inline_klass()->payload_offset(); 551 init_value = init_value->as_InlineType()->field_value_by_offset(offset, true); 552 if (ft == T_NARROWOOP) { 553 init_value = transform_later(new EncodePNode(init_value, init_value->bottom_type()->make_ptr())); 554 } 555 } 556 return init_value; 557 } 558 assert(alloc->in(AllocateNode::RawInitValue) == nullptr, "init value may not be null"); 559 return _igvn.zerocon(ft); 560 } else if (mem->is_Store()) { 561 Node* n = mem->in(MemNode::ValueIn); 562 BarrierSetC2* bs = BarrierSet::barrier_set()->barrier_set_c2(); 563 n = bs->step_over_gc_barrier(n); 564 return n; 565 } else if (mem->is_Phi()) { 566 // attempt to produce a Phi reflecting the values on the input paths of the Phi 567 Node_Stack value_phis(8); 568 Node* phi = value_from_mem_phi(mem, ft, ftype, adr_t, alloc, &value_phis, ValueSearchLimit); 569 if (phi != nullptr) { 570 return phi; 571 } else { 572 // Kill all new Phis 573 while(value_phis.is_nonempty()) { 574 Node* n = value_phis.node(); 575 _igvn.replace_node(n, C->top()); 576 value_phis.pop(); 577 } 578 } 579 } else if (mem->is_ArrayCopy()) { 580 Node* ctl = mem->in(0); 581 Node* m = mem->in(TypeFunc::Memory); 582 if (sfpt_ctl->is_Proj() && sfpt_ctl->as_Proj()->is_uncommon_trap_proj()) { 583 // pin the loads in the uncommon trap path 584 ctl = sfpt_ctl; 585 m = sfpt_mem; 586 } 587 return make_arraycopy_load(mem->as_ArrayCopy(), offset, ctl, m, ft, ftype, alloc); 588 } 589 } 590 // Something went wrong. 591 return nullptr; 592 } 593 594 // Search the last value stored into the inline type's fields (for flat arrays). 595 Node* PhaseMacroExpand::inline_type_from_mem(ciInlineKlass* vk, const TypeAryPtr* elem_adr_type, int elem_idx, int offset_in_element, bool null_free, AllocateNode* alloc, SafePointNode* sfpt) { 596 auto report_failure = [&](int field_offset_in_element) { 597 #ifndef PRODUCT 598 if (PrintEliminateAllocations) { 599 ciInlineKlass* elem_klass = elem_adr_type->elem()->inline_klass(); 600 int offset = field_offset_in_element + elem_klass->payload_offset(); 601 ciField* flattened_field = elem_klass->get_field_by_offset(offset, false); 602 assert(flattened_field != nullptr, "must have a field of type %s at offset %d", elem_klass->name()->as_utf8(), offset); 603 tty->print("=== At SafePoint node %d can't find value of field [%s] of array element [%d]", sfpt->_idx, flattened_field->name()->as_utf8(), elem_idx); 604 tty->print(", which prevents elimination of: "); 605 alloc->dump(); 606 } 607 #endif // PRODUCT 608 }; 609 610 // Create a new InlineTypeNode and retrieve the field values from memory 611 InlineTypeNode* vt = InlineTypeNode::make_uninitialized(_igvn, vk, false); 612 transform_later(vt); 613 if (null_free) { 614 vt->set_null_marker(_igvn); 615 } else { 616 int nm_offset_in_element = offset_in_element + vk->null_marker_offset_in_payload(); 617 const TypeAryPtr* nm_adr_type = elem_adr_type->with_field_offset(nm_offset_in_element); 618 Node* nm_value = value_from_mem(sfpt->memory(), sfpt->control(), T_BOOLEAN, TypeInt::BOOL, nm_adr_type, alloc); 619 if (nm_value != nullptr) { 620 vt->set_null_marker(_igvn, nm_value); 621 } else { 622 report_failure(nm_offset_in_element); 623 return nullptr; 624 } 625 } 626 627 for (int i = 0; i < vk->nof_declared_nonstatic_fields(); ++i) { 628 ciType* field_type = vt->field_type(i); 629 int field_offset_in_element = offset_in_element + vt->field_offset(i) - vk->payload_offset(); 630 Node* field_value = nullptr; 631 if (vt->field_is_flat(i)) { 632 field_value = inline_type_from_mem(field_type->as_inline_klass(), elem_adr_type, elem_idx, field_offset_in_element, vt->field_is_null_free(i), alloc, sfpt); 633 } else { 634 const Type* ft = Type::get_const_type(field_type); 635 BasicType bt = type2field[field_type->basic_type()]; 636 if (UseCompressedOops && !is_java_primitive(bt)) { 637 ft = ft->make_narrowoop(); 638 bt = T_NARROWOOP; 639 } 640 // Each inline type field has its own memory slice 641 const TypeAryPtr* field_adr_type = elem_adr_type->with_field_offset(field_offset_in_element); 642 field_value = value_from_mem(sfpt->memory(), sfpt->control(), bt, ft, field_adr_type, alloc); 643 if (field_value == nullptr) { 644 report_failure(field_offset_in_element); 645 } else if (ft->isa_narrowoop()) { 646 assert(UseCompressedOops, "unexpected narrow oop"); 647 if (field_value->is_EncodeP()) { 648 field_value = field_value->in(1); 649 } else if (!field_value->is_InlineType()) { 650 field_value = transform_later(new DecodeNNode(field_value, field_value->get_ptr_type())); 651 } 652 } 653 } 654 if (field_value != nullptr) { 655 vt->set_field_value(i, field_value); 656 } else { 657 return nullptr; 658 } 659 } 660 return vt; 661 } 662 663 // Check the possibility of scalar replacement. 664 bool PhaseMacroExpand::can_eliminate_allocation(PhaseIterGVN* igvn, AllocateNode *alloc, GrowableArray <SafePointNode *>* safepoints) { 665 // Scan the uses of the allocation to check for anything that would 666 // prevent us from eliminating it. 667 NOT_PRODUCT( const char* fail_eliminate = nullptr; ) 668 DEBUG_ONLY( Node* disq_node = nullptr; ) 669 bool can_eliminate = true; 670 bool reduce_merge_precheck = (safepoints == nullptr); 671 672 Unique_Node_List worklist; 673 Node* res = alloc->result_cast(); 674 const TypeOopPtr* res_type = nullptr; 675 if (res == nullptr) { 676 // All users were eliminated. 677 } else if (!res->is_CheckCastPP()) { 678 NOT_PRODUCT(fail_eliminate = "Allocation does not have unique CheckCastPP";) 679 can_eliminate = false; 680 } else { 681 worklist.push(res); 682 res_type = igvn->type(res)->isa_oopptr(); 683 if (res_type == nullptr) { 684 NOT_PRODUCT(fail_eliminate = "Neither instance or array allocation";) 685 can_eliminate = false; 686 } else if (!res_type->klass_is_exact()) { 687 NOT_PRODUCT(fail_eliminate = "Not an exact type.";) 688 can_eliminate = false; 689 } else if (res_type->isa_aryptr()) { 690 int length = alloc->in(AllocateNode::ALength)->find_int_con(-1); 691 if (length < 0) { 692 NOT_PRODUCT(fail_eliminate = "Array's size is not constant";) 693 can_eliminate = false; 694 } 695 } 696 } 697 698 while (can_eliminate && worklist.size() > 0) { 699 BarrierSetC2 *bs = BarrierSet::barrier_set()->barrier_set_c2(); 700 res = worklist.pop(); 701 for (DUIterator_Fast jmax, j = res->fast_outs(jmax); j < jmax && can_eliminate; j++) { 702 Node* use = res->fast_out(j); 703 704 if (use->is_AddP()) { 705 const TypePtr* addp_type = igvn->type(use)->is_ptr(); 706 int offset = addp_type->offset(); 707 708 if (offset == Type::OffsetTop || offset == Type::OffsetBot) { 709 NOT_PRODUCT(fail_eliminate = "Undefined field reference";) 710 can_eliminate = false; 711 break; 712 } 713 for (DUIterator_Fast kmax, k = use->fast_outs(kmax); 714 k < kmax && can_eliminate; k++) { 715 Node* n = use->fast_out(k); 716 if (!n->is_Store() && n->Opcode() != Op_CastP2X && !bs->is_gc_pre_barrier_node(n) && !reduce_merge_precheck) { 717 DEBUG_ONLY(disq_node = n;) 718 if (n->is_Load() || n->is_LoadStore()) { 719 NOT_PRODUCT(fail_eliminate = "Field load";) 720 } else { 721 NOT_PRODUCT(fail_eliminate = "Not store field reference";) 722 } 723 can_eliminate = false; 724 } 725 } 726 } else if (use->is_ArrayCopy() && 727 (use->as_ArrayCopy()->is_clonebasic() || 728 use->as_ArrayCopy()->is_arraycopy_validated() || 729 use->as_ArrayCopy()->is_copyof_validated() || 730 use->as_ArrayCopy()->is_copyofrange_validated()) && 731 use->in(ArrayCopyNode::Dest) == res) { 732 // ok to eliminate 733 } else if (use->is_SafePoint()) { 734 SafePointNode* sfpt = use->as_SafePoint(); 735 if (sfpt->is_Call() && sfpt->as_Call()->has_non_debug_use(res)) { 736 // Object is passed as argument. 737 DEBUG_ONLY(disq_node = use;) 738 NOT_PRODUCT(fail_eliminate = "Object is passed as argument";) 739 can_eliminate = false; 740 } 741 Node* sfptMem = sfpt->memory(); 742 if (sfptMem == nullptr || sfptMem->is_top()) { 743 DEBUG_ONLY(disq_node = use;) 744 NOT_PRODUCT(fail_eliminate = "null or TOP memory";) 745 can_eliminate = false; 746 } else if (!reduce_merge_precheck) { 747 assert(!res->is_Phi() || !res->as_Phi()->can_be_inline_type(), "Inline type allocations should not have safepoint uses"); 748 safepoints->append_if_missing(sfpt); 749 } 750 } else if (use->is_InlineType() && use->as_InlineType()->get_oop() == res) { 751 // Look at uses 752 for (DUIterator_Fast kmax, k = use->fast_outs(kmax); k < kmax; k++) { 753 Node* u = use->fast_out(k); 754 if (u->is_InlineType()) { 755 // Use in flat field can be eliminated 756 InlineTypeNode* vt = u->as_InlineType(); 757 for (uint i = 0; i < vt->field_count(); ++i) { 758 if (vt->field_value(i) == use && !vt->field_is_flat(i)) { 759 can_eliminate = false; // Use in non-flat field 760 break; 761 } 762 } 763 } else { 764 // Add other uses to the worklist to process individually 765 worklist.push(use); 766 } 767 } 768 } else if (use->Opcode() == Op_StoreX && use->in(MemNode::Address) == res) { 769 // Store to mark word of inline type larval buffer 770 assert(res_type->is_inlinetypeptr(), "Unexpected store to mark word"); 771 } else if (res_type->is_inlinetypeptr() && (use->Opcode() == Op_MemBarRelease || use->Opcode() == Op_MemBarStoreStore)) { 772 // Inline type buffer allocations are followed by a membar 773 } else if (reduce_merge_precheck && 774 (use->is_Phi() || use->is_EncodeP() || 775 use->Opcode() == Op_MemBarRelease || 776 (UseStoreStoreForCtor && use->Opcode() == Op_MemBarStoreStore))) { 777 // Nothing to do 778 } else if (use->Opcode() != Op_CastP2X) { // CastP2X is used by card mark 779 if (use->is_Phi()) { 780 if (use->outcnt() == 1 && use->unique_out()->Opcode() == Op_Return) { 781 NOT_PRODUCT(fail_eliminate = "Object is return value";) 782 } else { 783 NOT_PRODUCT(fail_eliminate = "Object is referenced by Phi";) 784 } 785 DEBUG_ONLY(disq_node = use;) 786 } else { 787 if (use->Opcode() == Op_Return) { 788 NOT_PRODUCT(fail_eliminate = "Object is return value";) 789 } else { 790 NOT_PRODUCT(fail_eliminate = "Object is referenced by node";) 791 } 792 DEBUG_ONLY(disq_node = use;) 793 } 794 can_eliminate = false; 795 } else { 796 assert(use->Opcode() == Op_CastP2X, "should be"); 797 assert(!use->has_out_with(Op_OrL), "should have been removed because oop is never null"); 798 } 799 } 800 } 801 802 #ifndef PRODUCT 803 if (PrintEliminateAllocations && safepoints != nullptr) { 804 if (can_eliminate) { 805 tty->print("Scalar "); 806 if (res == nullptr) 807 alloc->dump(); 808 else 809 res->dump(); 810 } else { 811 tty->print("NotScalar (%s)", fail_eliminate); 812 if (res == nullptr) 813 alloc->dump(); 814 else 815 res->dump(); 816 #ifdef ASSERT 817 if (disq_node != nullptr) { 818 tty->print(" >>>> "); 819 disq_node->dump(); 820 } 821 #endif /*ASSERT*/ 822 } 823 } 824 825 if (TraceReduceAllocationMerges && !can_eliminate && reduce_merge_precheck) { 826 tty->print_cr("\tCan't eliminate allocation because '%s': ", fail_eliminate != nullptr ? fail_eliminate : ""); 827 DEBUG_ONLY(if (disq_node != nullptr) disq_node->dump();) 828 } 829 #endif 830 return can_eliminate; 831 } 832 833 void PhaseMacroExpand::undo_previous_scalarizations(GrowableArray <SafePointNode *> safepoints_done, AllocateNode* alloc) { 834 Node* res = alloc->result_cast(); 835 int nfields = 0; 836 assert(res == nullptr || res->is_CheckCastPP(), "unexpected AllocateNode result"); 837 838 if (res != nullptr) { 839 const TypeOopPtr* res_type = _igvn.type(res)->isa_oopptr(); 840 841 if (res_type->isa_instptr()) { 842 // find the fields of the class which will be needed for safepoint debug information 843 ciInstanceKlass* iklass = res_type->is_instptr()->instance_klass(); 844 nfields = iklass->nof_nonstatic_fields(); 845 } else { 846 // find the array's elements which will be needed for safepoint debug information 847 nfields = alloc->in(AllocateNode::ALength)->find_int_con(-1); 848 assert(nfields >= 0, "must be an array klass."); 849 } 850 } 851 852 // rollback processed safepoints 853 while (safepoints_done.length() > 0) { 854 SafePointNode* sfpt_done = safepoints_done.pop(); 855 // remove any extra entries we added to the safepoint 856 uint last = sfpt_done->req() - 1; 857 for (int k = 0; k < nfields; k++) { 858 sfpt_done->del_req(last--); 859 } 860 JVMState *jvms = sfpt_done->jvms(); 861 jvms->set_endoff(sfpt_done->req()); 862 // Now make a pass over the debug information replacing any references 863 // to SafePointScalarObjectNode with the allocated object. 864 int start = jvms->debug_start(); 865 int end = jvms->debug_end(); 866 for (int i = start; i < end; i++) { 867 if (sfpt_done->in(i)->is_SafePointScalarObject()) { 868 SafePointScalarObjectNode* scobj = sfpt_done->in(i)->as_SafePointScalarObject(); 869 if (scobj->first_index(jvms) == sfpt_done->req() && 870 scobj->n_fields() == (uint)nfields) { 871 assert(scobj->alloc() == alloc, "sanity"); 872 sfpt_done->set_req(i, res); 873 } 874 } 875 } 876 _igvn._worklist.push(sfpt_done); 877 } 878 } 879 880 void PhaseMacroExpand::process_field_value_at_safepoint(const Type* field_type, Node* field_val, SafePointNode* sfpt, Unique_Node_List* value_worklist) { 881 if (UseCompressedOops && field_type->isa_narrowoop()) { 882 // Enable "DecodeN(EncodeP(Allocate)) --> Allocate" transformation 883 // to be able scalar replace the allocation. 884 if (field_val->is_EncodeP()) { 885 field_val = field_val->in(1); 886 } else if (!field_val->is_InlineType()) { 887 field_val = transform_later(new DecodeNNode(field_val, field_val->get_ptr_type())); 888 } 889 } 890 891 // Keep track of inline types to scalarize them later 892 if (field_val->is_InlineType()) { 893 value_worklist->push(field_val); 894 } else if (field_val->is_Phi()) { 895 PhiNode* phi = field_val->as_Phi(); 896 // Eagerly replace inline type phis now since we could be removing an inline type allocation where we must 897 // scalarize all its fields in safepoints. 898 field_val = phi->try_push_inline_types_down(&_igvn, true); 899 if (field_val->is_InlineType()) { 900 value_worklist->push(field_val); 901 } 902 } 903 sfpt->add_req(field_val); 904 } 905 906 bool PhaseMacroExpand::add_array_elems_to_safepoint(AllocateNode* alloc, const TypeAryPtr* array_type, SafePointNode* sfpt, Unique_Node_List* value_worklist) { 907 const Type* elem_type = array_type->elem(); 908 BasicType basic_elem_type = elem_type->array_element_basic_type(); 909 910 intptr_t elem_size; 911 if (array_type->is_flat()) { 912 elem_size = array_type->flat_elem_size(); 913 } else { 914 elem_size = type2aelembytes(basic_elem_type); 915 } 916 917 int n_elems = alloc->in(AllocateNode::ALength)->get_int(); 918 for (int elem_idx = 0; elem_idx < n_elems; elem_idx++) { 919 intptr_t elem_offset = arrayOopDesc::base_offset_in_bytes(basic_elem_type) + elem_idx * elem_size; 920 const TypeAryPtr* elem_adr_type = array_type->with_offset(elem_offset); 921 Node* elem_val; 922 if (array_type->is_flat()) { 923 ciInlineKlass* elem_klass = elem_type->inline_klass(); 924 assert(elem_klass->maybe_flat_in_array(), "must be flat in array"); 925 elem_val = inline_type_from_mem(elem_klass, elem_adr_type, elem_idx, 0, array_type->is_null_free(), alloc, sfpt); 926 } else { 927 elem_val = value_from_mem(sfpt->memory(), sfpt->control(), basic_elem_type, elem_type, elem_adr_type, alloc); 928 #ifndef PRODUCT 929 if (PrintEliminateAllocations && elem_val == nullptr) { 930 tty->print("=== At SafePoint node %d can't find value of array element [%d]", sfpt->_idx, elem_idx); 931 tty->print(", which prevents elimination of: "); 932 alloc->dump(); 933 } 934 #endif // PRODUCT 935 } 936 if (elem_val == nullptr) { 937 return false; 938 } 939 940 process_field_value_at_safepoint(elem_type, elem_val, sfpt, value_worklist); 941 } 942 943 return true; 944 } 945 946 // Recursively adds all flattened fields of a type 'iklass' inside 'base' to 'sfpt'. 947 // 'offset_minus_header' refers to the offset of the payload of 'iklass' inside 'base' minus the 948 // payload offset of 'iklass'. If 'base' is of type 'iklass' then 'offset_minus_header' == 0. 949 bool PhaseMacroExpand::add_inst_fields_to_safepoint(ciInstanceKlass* iklass, AllocateNode* alloc, Node* base, int offset_minus_header, SafePointNode* sfpt, Unique_Node_List* value_worklist) { 950 const TypeInstPtr* base_type = _igvn.type(base)->is_instptr(); 951 auto report_failure = [&](int offset) { 952 #ifndef PRODUCT 953 if (PrintEliminateAllocations) { 954 ciInstanceKlass* base_klass = base_type->instance_klass(); 955 ciField* flattened_field = base_klass->get_field_by_offset(offset, false); 956 assert(flattened_field != nullptr, "must have a field of type %s at offset %d", base_klass->name()->as_utf8(), offset); 957 tty->print("=== At SafePoint node %d can't find value of field: ", sfpt->_idx); 958 flattened_field->print(); 959 int field_idx = C->alias_type(flattened_field)->index(); 960 tty->print(" (alias_idx=%d)", field_idx); 961 tty->print(", which prevents elimination of: "); 962 base->dump(); 963 } 964 #endif // PRODUCT 965 }; 966 967 for (int i = 0; i < iklass->nof_declared_nonstatic_fields(); i++) { 968 ciField* field = iklass->declared_nonstatic_field_at(i); 969 if (field->is_flat()) { 970 ciInlineKlass* fvk = field->type()->as_inline_klass(); 971 int field_offset_minus_header = offset_minus_header + field->offset_in_bytes() - fvk->payload_offset(); 972 bool success = add_inst_fields_to_safepoint(fvk, alloc, base, field_offset_minus_header, sfpt, value_worklist); 973 if (!success) { 974 return false; 975 } 976 977 // The null marker of a field is added right after we scalarize that field 978 if (!field->is_null_free()) { 979 int nm_offset = offset_minus_header + field->null_marker_offset(); 980 Node* null_marker = value_from_mem(sfpt->memory(), sfpt->control(), T_BOOLEAN, TypeInt::BOOL, base_type->with_offset(nm_offset), alloc); 981 if (null_marker == nullptr) { 982 report_failure(nm_offset); 983 return false; 984 } 985 process_field_value_at_safepoint(TypeInt::BOOL, null_marker, sfpt, value_worklist); 986 } 987 988 continue; 989 } 990 991 int offset = offset_minus_header + field->offset_in_bytes(); 992 ciType* elem_type = field->type(); 993 BasicType basic_elem_type = field->layout_type(); 994 995 const Type* field_type; 996 if (is_reference_type(basic_elem_type)) { 997 if (!elem_type->is_loaded()) { 998 field_type = TypeInstPtr::BOTTOM; 999 } else { 1000 field_type = TypeOopPtr::make_from_klass(elem_type->as_klass()); 1001 } 1002 if (UseCompressedOops) { 1003 field_type = field_type->make_narrowoop(); 1004 basic_elem_type = T_NARROWOOP; 1005 } 1006 } else { 1007 field_type = Type::get_const_basic_type(basic_elem_type); 1008 } 1009 1010 const TypeInstPtr* field_addr_type = base_type->add_offset(offset)->isa_instptr(); 1011 Node* field_val = value_from_mem(sfpt->memory(), sfpt->control(), basic_elem_type, field_type, field_addr_type, alloc); 1012 if (field_val == nullptr) { 1013 report_failure(offset); 1014 return false; 1015 } 1016 process_field_value_at_safepoint(field_type, field_val, sfpt, value_worklist); 1017 } 1018 1019 return true; 1020 } 1021 1022 SafePointScalarObjectNode* PhaseMacroExpand::create_scalarized_object_description(AllocateNode* alloc, SafePointNode* sfpt, 1023 Unique_Node_List* value_worklist) { 1024 // Fields of scalar objs are referenced only at the end 1025 // of regular debuginfo at the last (youngest) JVMS. 1026 // Record relative start index. 1027 ciInstanceKlass* iklass = nullptr; 1028 const TypeOopPtr* res_type = nullptr; 1029 int nfields = 0; 1030 uint first_ind = (sfpt->req() - sfpt->jvms()->scloff()); 1031 Node* res = alloc->result_cast(); 1032 1033 assert(res == nullptr || res->is_CheckCastPP(), "unexpected AllocateNode result"); 1034 assert(sfpt->jvms() != nullptr, "missed JVMS"); 1035 uint before_sfpt_req = sfpt->req(); 1036 1037 if (res != nullptr) { // Could be null when there are no users 1038 res_type = _igvn.type(res)->isa_oopptr(); 1039 1040 if (res_type->isa_instptr()) { 1041 // find the fields of the class which will be needed for safepoint debug information 1042 iklass = res_type->is_instptr()->instance_klass(); 1043 nfields = iklass->nof_nonstatic_fields(); 1044 } else { 1045 // find the array's elements which will be needed for safepoint debug information 1046 nfields = alloc->in(AllocateNode::ALength)->find_int_con(-1); 1047 assert(nfields >= 0, "must be an array klass."); 1048 } 1049 1050 if (res->bottom_type()->is_inlinetypeptr()) { 1051 // Nullable inline types have a null marker field which is added to the safepoint when scalarizing them (see 1052 // InlineTypeNode::make_scalar_in_safepoint()). When having circular inline types, we stop scalarizing at depth 1 1053 // to avoid an endless recursion. Therefore, we do not have a SafePointScalarObjectNode node here, yet. 1054 // We are about to create a SafePointScalarObjectNode as if this is a normal object. Add an additional int input 1055 // with value 1 which sets the null marker to true to indicate that the object is always non-null. This input is checked 1056 // later in PhaseOutput::filLocArray() for inline types. 1057 sfpt->add_req(_igvn.intcon(1)); 1058 } 1059 } 1060 1061 SafePointScalarObjectNode* sobj = new SafePointScalarObjectNode(res_type, alloc, first_ind, sfpt->jvms()->depth(), nfields); 1062 sobj->init_req(0, C->root()); 1063 transform_later(sobj); 1064 1065 if (res == nullptr) { 1066 sfpt->jvms()->set_endoff(sfpt->req()); 1067 return sobj; 1068 } 1069 1070 bool success; 1071 if (iklass == nullptr) { 1072 success = add_array_elems_to_safepoint(alloc, res_type->is_aryptr(), sfpt, value_worklist); 1073 } else { 1074 success = add_inst_fields_to_safepoint(iklass, alloc, res, 0, sfpt, value_worklist); 1075 } 1076 1077 // We weren't able to find a value for this field, remove all the fields added to the safepoint 1078 if (!success) { 1079 for (uint i = sfpt->req() - 1; i >= before_sfpt_req; i--) { 1080 sfpt->del_req(i); 1081 } 1082 _igvn._worklist.push(sfpt); 1083 return nullptr; 1084 } 1085 1086 sfpt->jvms()->set_endoff(sfpt->req()); 1087 return sobj; 1088 } 1089 1090 // Do scalar replacement. 1091 bool PhaseMacroExpand::scalar_replacement(AllocateNode *alloc, GrowableArray <SafePointNode *>& safepoints) { 1092 GrowableArray <SafePointNode *> safepoints_done; 1093 Node* res = alloc->result_cast(); 1094 assert(res == nullptr || res->is_CheckCastPP(), "unexpected AllocateNode result"); 1095 const TypeOopPtr* res_type = nullptr; 1096 if (res != nullptr) { // Could be null when there are no users 1097 res_type = _igvn.type(res)->isa_oopptr(); 1098 } 1099 1100 // Process the safepoint uses 1101 Unique_Node_List value_worklist; 1102 while (safepoints.length() > 0) { 1103 SafePointNode* sfpt = safepoints.pop(); 1104 SafePointScalarObjectNode* sobj = create_scalarized_object_description(alloc, sfpt, &value_worklist); 1105 1106 if (sobj == nullptr) { 1107 undo_previous_scalarizations(safepoints_done, alloc); 1108 return false; 1109 } 1110 1111 // Now make a pass over the debug information replacing any references 1112 // to the allocated object with "sobj" 1113 JVMState *jvms = sfpt->jvms(); 1114 sfpt->replace_edges_in_range(res, sobj, jvms->debug_start(), jvms->debug_end(), &_igvn); 1115 _igvn._worklist.push(sfpt); 1116 1117 // keep it for rollback 1118 safepoints_done.append_if_missing(sfpt); 1119 } 1120 // Scalarize inline types that were added to the safepoint. 1121 // Don't allow linking a constant oop (if available) for flat array elements 1122 // because Deoptimization::reassign_flat_array_elements needs field values. 1123 bool allow_oop = (res_type != nullptr) && !res_type->is_flat(); 1124 for (uint i = 0; i < value_worklist.size(); ++i) { 1125 InlineTypeNode* vt = value_worklist.at(i)->as_InlineType(); 1126 vt->make_scalar_in_safepoints(&_igvn, allow_oop); 1127 } 1128 return true; 1129 } 1130 1131 static void disconnect_projections(MultiNode* n, PhaseIterGVN& igvn) { 1132 Node* ctl_proj = n->proj_out_or_null(TypeFunc::Control); 1133 Node* mem_proj = n->proj_out_or_null(TypeFunc::Memory); 1134 if (ctl_proj != nullptr) { 1135 igvn.replace_node(ctl_proj, n->in(0)); 1136 } 1137 if (mem_proj != nullptr) { 1138 igvn.replace_node(mem_proj, n->in(TypeFunc::Memory)); 1139 } 1140 } 1141 1142 // Process users of eliminated allocation. 1143 void PhaseMacroExpand::process_users_of_allocation(CallNode *alloc, bool inline_alloc) { 1144 Unique_Node_List worklist; 1145 Node* res = alloc->result_cast(); 1146 if (res != nullptr) { 1147 worklist.push(res); 1148 } 1149 while (worklist.size() > 0) { 1150 res = worklist.pop(); 1151 for (DUIterator_Last jmin, j = res->last_outs(jmin); j >= jmin; ) { 1152 Node *use = res->last_out(j); 1153 uint oc1 = res->outcnt(); 1154 1155 if (use->is_AddP()) { 1156 for (DUIterator_Last kmin, k = use->last_outs(kmin); k >= kmin; ) { 1157 Node *n = use->last_out(k); 1158 uint oc2 = use->outcnt(); 1159 if (n->is_Store()) { 1160 for (DUIterator_Fast pmax, p = n->fast_outs(pmax); p < pmax; p++) { 1161 MemBarNode* mb = n->fast_out(p)->isa_MemBar(); 1162 if (mb != nullptr && mb->req() <= MemBarNode::Precedent && mb->in(MemBarNode::Precedent) == n) { 1163 // MemBarVolatiles should have been removed by MemBarNode::Ideal() for non-inline allocations 1164 assert(inline_alloc, "MemBarVolatile should be eliminated for non-escaping object"); 1165 mb->remove(&_igvn); 1166 } 1167 } 1168 _igvn.replace_node(n, n->in(MemNode::Memory)); 1169 } else { 1170 eliminate_gc_barrier(n); 1171 } 1172 k -= (oc2 - use->outcnt()); 1173 } 1174 _igvn.remove_dead_node(use); 1175 } else if (use->is_ArrayCopy()) { 1176 // Disconnect ArrayCopy node 1177 ArrayCopyNode* ac = use->as_ArrayCopy(); 1178 if (ac->is_clonebasic()) { 1179 Node* membar_after = ac->proj_out(TypeFunc::Control)->unique_ctrl_out(); 1180 disconnect_projections(ac, _igvn); 1181 assert(alloc->in(TypeFunc::Memory)->is_Proj() && alloc->in(TypeFunc::Memory)->in(0)->Opcode() == Op_MemBarCPUOrder, "mem barrier expected before allocation"); 1182 Node* membar_before = alloc->in(TypeFunc::Memory)->in(0); 1183 disconnect_projections(membar_before->as_MemBar(), _igvn); 1184 if (membar_after->is_MemBar()) { 1185 disconnect_projections(membar_after->as_MemBar(), _igvn); 1186 } 1187 } else { 1188 assert(ac->is_arraycopy_validated() || 1189 ac->is_copyof_validated() || 1190 ac->is_copyofrange_validated(), "unsupported"); 1191 CallProjections* callprojs = ac->extract_projections(true); 1192 1193 _igvn.replace_node(callprojs->fallthrough_ioproj, ac->in(TypeFunc::I_O)); 1194 _igvn.replace_node(callprojs->fallthrough_memproj, ac->in(TypeFunc::Memory)); 1195 _igvn.replace_node(callprojs->fallthrough_catchproj, ac->in(TypeFunc::Control)); 1196 1197 // Set control to top. IGVN will remove the remaining projections 1198 ac->set_req(0, top()); 1199 ac->replace_edge(res, top(), &_igvn); 1200 1201 // Disconnect src right away: it can help find new 1202 // opportunities for allocation elimination 1203 Node* src = ac->in(ArrayCopyNode::Src); 1204 ac->replace_edge(src, top(), &_igvn); 1205 // src can be top at this point if src and dest of the 1206 // arraycopy were the same 1207 if (src->outcnt() == 0 && !src->is_top()) { 1208 _igvn.remove_dead_node(src); 1209 } 1210 } 1211 _igvn._worklist.push(ac); 1212 } else if (use->is_InlineType()) { 1213 assert(use->as_InlineType()->get_oop() == res, "unexpected inline type ptr use"); 1214 // Cut off oop input and remove known instance id from type 1215 _igvn.rehash_node_delayed(use); 1216 use->as_InlineType()->set_oop(_igvn, _igvn.zerocon(T_OBJECT)); 1217 const TypeOopPtr* toop = _igvn.type(use)->is_oopptr()->cast_to_instance_id(TypeOopPtr::InstanceBot); 1218 _igvn.set_type(use, toop); 1219 use->as_InlineType()->set_type(toop); 1220 // Process users 1221 for (DUIterator_Fast kmax, k = use->fast_outs(kmax); k < kmax; k++) { 1222 Node* u = use->fast_out(k); 1223 if (!u->is_InlineType()) { 1224 worklist.push(u); 1225 } 1226 } 1227 } else if (use->Opcode() == Op_StoreX && use->in(MemNode::Address) == res) { 1228 // Store to mark word of inline type larval buffer 1229 assert(inline_alloc, "Unexpected store to mark word"); 1230 _igvn.replace_node(use, use->in(MemNode::Memory)); 1231 } else if (use->Opcode() == Op_MemBarRelease || use->Opcode() == Op_MemBarStoreStore) { 1232 // Inline type buffer allocations are followed by a membar 1233 assert(inline_alloc, "Unexpected MemBarRelease"); 1234 use->as_MemBar()->remove(&_igvn); 1235 } else { 1236 eliminate_gc_barrier(use); 1237 } 1238 j -= (oc1 - res->outcnt()); 1239 } 1240 assert(res->outcnt() == 0, "all uses of allocated objects must be deleted"); 1241 _igvn.remove_dead_node(res); 1242 } 1243 1244 // 1245 // Process other users of allocation's projections 1246 // 1247 if (_callprojs->resproj[0] != nullptr && _callprojs->resproj[0]->outcnt() != 0) { 1248 // First disconnect stores captured by Initialize node. 1249 // If Initialize node is eliminated first in the following code, 1250 // it will kill such stores and DUIterator_Last will assert. 1251 for (DUIterator_Fast jmax, j = _callprojs->resproj[0]->fast_outs(jmax); j < jmax; j++) { 1252 Node* use = _callprojs->resproj[0]->fast_out(j); 1253 if (use->is_AddP()) { 1254 // raw memory addresses used only by the initialization 1255 _igvn.replace_node(use, C->top()); 1256 --j; --jmax; 1257 } 1258 } 1259 for (DUIterator_Last jmin, j = _callprojs->resproj[0]->last_outs(jmin); j >= jmin; ) { 1260 Node* use = _callprojs->resproj[0]->last_out(j); 1261 uint oc1 = _callprojs->resproj[0]->outcnt(); 1262 if (use->is_Initialize()) { 1263 // Eliminate Initialize node. 1264 InitializeNode *init = use->as_Initialize(); 1265 assert(init->outcnt() <= 2, "only a control and memory projection expected"); 1266 Node *ctrl_proj = init->proj_out_or_null(TypeFunc::Control); 1267 if (ctrl_proj != nullptr) { 1268 _igvn.replace_node(ctrl_proj, init->in(TypeFunc::Control)); 1269 #ifdef ASSERT 1270 // If the InitializeNode has no memory out, it will die, and tmp will become null 1271 Node* tmp = init->in(TypeFunc::Control); 1272 assert(tmp == nullptr || tmp == _callprojs->fallthrough_catchproj, "allocation control projection"); 1273 #endif 1274 } 1275 Node *mem_proj = init->proj_out_or_null(TypeFunc::Memory); 1276 if (mem_proj != nullptr) { 1277 Node *mem = init->in(TypeFunc::Memory); 1278 #ifdef ASSERT 1279 if (mem->is_MergeMem()) { 1280 assert(mem->in(TypeFunc::Memory) == _callprojs->fallthrough_memproj, "allocation memory projection"); 1281 } else { 1282 assert(mem == _callprojs->fallthrough_memproj, "allocation memory projection"); 1283 } 1284 #endif 1285 _igvn.replace_node(mem_proj, mem); 1286 } 1287 } else if (use->Opcode() == Op_MemBarStoreStore) { 1288 // Inline type buffer allocations are followed by a membar 1289 assert(inline_alloc, "Unexpected MemBarStoreStore"); 1290 use->as_MemBar()->remove(&_igvn); 1291 } else { 1292 assert(false, "only Initialize or AddP expected"); 1293 } 1294 j -= (oc1 - _callprojs->resproj[0]->outcnt()); 1295 } 1296 } 1297 if (_callprojs->fallthrough_catchproj != nullptr) { 1298 _igvn.replace_node(_callprojs->fallthrough_catchproj, alloc->in(TypeFunc::Control)); 1299 } 1300 if (_callprojs->fallthrough_memproj != nullptr) { 1301 _igvn.replace_node(_callprojs->fallthrough_memproj, alloc->in(TypeFunc::Memory)); 1302 } 1303 if (_callprojs->catchall_memproj != nullptr) { 1304 _igvn.replace_node(_callprojs->catchall_memproj, C->top()); 1305 } 1306 if (_callprojs->fallthrough_ioproj != nullptr) { 1307 _igvn.replace_node(_callprojs->fallthrough_ioproj, alloc->in(TypeFunc::I_O)); 1308 } 1309 if (_callprojs->catchall_ioproj != nullptr) { 1310 _igvn.replace_node(_callprojs->catchall_ioproj, C->top()); 1311 } 1312 if (_callprojs->catchall_catchproj != nullptr) { 1313 _igvn.replace_node(_callprojs->catchall_catchproj, C->top()); 1314 } 1315 } 1316 1317 bool PhaseMacroExpand::eliminate_allocate_node(AllocateNode *alloc) { 1318 // If reallocation fails during deoptimization we'll pop all 1319 // interpreter frames for this compiled frame and that won't play 1320 // nice with JVMTI popframe. 1321 // We avoid this issue by eager reallocation when the popframe request 1322 // is received. 1323 if (!EliminateAllocations) { 1324 return false; 1325 } 1326 Node* klass = alloc->in(AllocateNode::KlassNode); 1327 const TypeKlassPtr* tklass = _igvn.type(klass)->is_klassptr(); 1328 1329 // Attempt to eliminate inline type buffer allocations 1330 // regardless of usage and escape/replaceable status. 1331 bool inline_alloc = tklass->isa_instklassptr() && 1332 tklass->is_instklassptr()->instance_klass()->is_inlinetype(); 1333 if (!alloc->_is_non_escaping && !inline_alloc) { 1334 return false; 1335 } 1336 // Eliminate boxing allocations which are not used 1337 // regardless scalar replaceable status. 1338 Node* res = alloc->result_cast(); 1339 bool boxing_alloc = (res == nullptr) && C->eliminate_boxing() && 1340 tklass->isa_instklassptr() && 1341 tklass->is_instklassptr()->instance_klass()->is_box_klass(); 1342 if (!alloc->_is_scalar_replaceable && !boxing_alloc && !inline_alloc) { 1343 return false; 1344 } 1345 1346 _callprojs = alloc->extract_projections(false /*separate_io_proj*/, false /*do_asserts*/); 1347 1348 GrowableArray <SafePointNode *> safepoints; 1349 if (!can_eliminate_allocation(&_igvn, alloc, &safepoints)) { 1350 return false; 1351 } 1352 1353 if (!alloc->_is_scalar_replaceable) { 1354 assert(res == nullptr || inline_alloc, "sanity"); 1355 // We can only eliminate allocation if all debug info references 1356 // are already replaced with SafePointScalarObject because 1357 // we can't search for a fields value without instance_id. 1358 if (safepoints.length() > 0) { 1359 return false; 1360 } 1361 } 1362 1363 if (!scalar_replacement(alloc, safepoints)) { 1364 return false; 1365 } 1366 1367 CompileLog* log = C->log(); 1368 if (log != nullptr) { 1369 log->head("eliminate_allocation type='%d'", 1370 log->identify(tklass->exact_klass())); 1371 JVMState* p = alloc->jvms(); 1372 while (p != nullptr) { 1373 log->elem("jvms bci='%d' method='%d'", p->bci(), log->identify(p->method())); 1374 p = p->caller(); 1375 } 1376 log->tail("eliminate_allocation"); 1377 } 1378 1379 process_users_of_allocation(alloc, inline_alloc); 1380 1381 #ifndef PRODUCT 1382 if (PrintEliminateAllocations) { 1383 if (alloc->is_AllocateArray()) 1384 tty->print_cr("++++ Eliminated: %d AllocateArray", alloc->_idx); 1385 else 1386 tty->print_cr("++++ Eliminated: %d Allocate", alloc->_idx); 1387 } 1388 #endif 1389 1390 return true; 1391 } 1392 1393 bool PhaseMacroExpand::eliminate_boxing_node(CallStaticJavaNode *boxing) { 1394 // EA should remove all uses of non-escaping boxing node. 1395 if (!C->eliminate_boxing() || boxing->proj_out_or_null(TypeFunc::Parms) != nullptr) { 1396 return false; 1397 } 1398 1399 assert(boxing->result_cast() == nullptr, "unexpected boxing node result"); 1400 1401 _callprojs = boxing->extract_projections(false /*separate_io_proj*/, false /*do_asserts*/); 1402 1403 const TypeTuple* r = boxing->tf()->range_sig(); 1404 assert(r->cnt() > TypeFunc::Parms, "sanity"); 1405 const TypeInstPtr* t = r->field_at(TypeFunc::Parms)->isa_instptr(); 1406 assert(t != nullptr, "sanity"); 1407 1408 CompileLog* log = C->log(); 1409 if (log != nullptr) { 1410 log->head("eliminate_boxing type='%d'", 1411 log->identify(t->instance_klass())); 1412 JVMState* p = boxing->jvms(); 1413 while (p != nullptr) { 1414 log->elem("jvms bci='%d' method='%d'", p->bci(), log->identify(p->method())); 1415 p = p->caller(); 1416 } 1417 log->tail("eliminate_boxing"); 1418 } 1419 1420 process_users_of_allocation(boxing); 1421 1422 #ifndef PRODUCT 1423 if (PrintEliminateAllocations) { 1424 tty->print("++++ Eliminated: %d ", boxing->_idx); 1425 boxing->method()->print_short_name(tty); 1426 tty->cr(); 1427 } 1428 #endif 1429 1430 return true; 1431 } 1432 1433 1434 Node* PhaseMacroExpand::make_load(Node* ctl, Node* mem, Node* base, int offset, const Type* value_type, BasicType bt) { 1435 Node* adr = basic_plus_adr(base, offset); 1436 const TypePtr* adr_type = adr->bottom_type()->is_ptr(); 1437 Node* value = LoadNode::make(_igvn, ctl, mem, adr, adr_type, value_type, bt, MemNode::unordered); 1438 transform_later(value); 1439 return value; 1440 } 1441 1442 1443 Node* PhaseMacroExpand::make_store(Node* ctl, Node* mem, Node* base, int offset, Node* value, BasicType bt) { 1444 Node* adr = basic_plus_adr(base, offset); 1445 mem = StoreNode::make(_igvn, ctl, mem, adr, nullptr, value, bt, MemNode::unordered); 1446 transform_later(mem); 1447 return mem; 1448 } 1449 1450 //============================================================================= 1451 // 1452 // A L L O C A T I O N 1453 // 1454 // Allocation attempts to be fast in the case of frequent small objects. 1455 // It breaks down like this: 1456 // 1457 // 1) Size in doublewords is computed. This is a constant for objects and 1458 // variable for most arrays. Doubleword units are used to avoid size 1459 // overflow of huge doubleword arrays. We need doublewords in the end for 1460 // rounding. 1461 // 1462 // 2) Size is checked for being 'too large'. Too-large allocations will go 1463 // the slow path into the VM. The slow path can throw any required 1464 // exceptions, and does all the special checks for very large arrays. The 1465 // size test can constant-fold away for objects. For objects with 1466 // finalizers it constant-folds the otherway: you always go slow with 1467 // finalizers. 1468 // 1469 // 3) If NOT using TLABs, this is the contended loop-back point. 1470 // Load-Locked the heap top. If using TLABs normal-load the heap top. 1471 // 1472 // 4) Check that heap top + size*8 < max. If we fail go the slow ` route. 1473 // NOTE: "top+size*8" cannot wrap the 4Gig line! Here's why: for largish 1474 // "size*8" we always enter the VM, where "largish" is a constant picked small 1475 // enough that there's always space between the eden max and 4Gig (old space is 1476 // there so it's quite large) and large enough that the cost of entering the VM 1477 // is dwarfed by the cost to initialize the space. 1478 // 1479 // 5) If NOT using TLABs, Store-Conditional the adjusted heap top back 1480 // down. If contended, repeat at step 3. If using TLABs normal-store 1481 // adjusted heap top back down; there is no contention. 1482 // 1483 // 6) If !ZeroTLAB then Bulk-clear the object/array. Fill in klass & mark 1484 // fields. 1485 // 1486 // 7) Merge with the slow-path; cast the raw memory pointer to the correct 1487 // oop flavor. 1488 // 1489 //============================================================================= 1490 // FastAllocateSizeLimit value is in DOUBLEWORDS. 1491 // Allocations bigger than this always go the slow route. 1492 // This value must be small enough that allocation attempts that need to 1493 // trigger exceptions go the slow route. Also, it must be small enough so 1494 // that heap_top + size_in_bytes does not wrap around the 4Gig limit. 1495 //=============================================================================j// 1496 // %%% Here is an old comment from parseHelper.cpp; is it outdated? 1497 // The allocator will coalesce int->oop copies away. See comment in 1498 // coalesce.cpp about how this works. It depends critically on the exact 1499 // code shape produced here, so if you are changing this code shape 1500 // make sure the GC info for the heap-top is correct in and around the 1501 // slow-path call. 1502 // 1503 1504 void PhaseMacroExpand::expand_allocate_common( 1505 AllocateNode* alloc, // allocation node to be expanded 1506 Node* length, // array length for an array allocation 1507 Node* init_val, // value to initialize the array with 1508 const TypeFunc* slow_call_type, // Type of slow call 1509 address slow_call_address, // Address of slow call 1510 Node* valid_length_test // whether length is valid or not 1511 ) 1512 { 1513 Node* ctrl = alloc->in(TypeFunc::Control); 1514 Node* mem = alloc->in(TypeFunc::Memory); 1515 Node* i_o = alloc->in(TypeFunc::I_O); 1516 Node* size_in_bytes = alloc->in(AllocateNode::AllocSize); 1517 Node* klass_node = alloc->in(AllocateNode::KlassNode); 1518 Node* initial_slow_test = alloc->in(AllocateNode::InitialTest); 1519 assert(ctrl != nullptr, "must have control"); 1520 1521 // We need a Region and corresponding Phi's to merge the slow-path and fast-path results. 1522 // they will not be used if "always_slow" is set 1523 enum { slow_result_path = 1, fast_result_path = 2 }; 1524 Node *result_region = nullptr; 1525 Node *result_phi_rawmem = nullptr; 1526 Node *result_phi_rawoop = nullptr; 1527 Node *result_phi_i_o = nullptr; 1528 1529 // The initial slow comparison is a size check, the comparison 1530 // we want to do is a BoolTest::gt 1531 bool expand_fast_path = true; 1532 int tv = _igvn.find_int_con(initial_slow_test, -1); 1533 if (tv >= 0) { 1534 // InitialTest has constant result 1535 // 0 - can fit in TLAB 1536 // 1 - always too big or negative 1537 assert(tv <= 1, "0 or 1 if a constant"); 1538 expand_fast_path = (tv == 0); 1539 initial_slow_test = nullptr; 1540 } else { 1541 initial_slow_test = BoolNode::make_predicate(initial_slow_test, &_igvn); 1542 } 1543 1544 if (!UseTLAB) { 1545 // Force slow-path allocation 1546 expand_fast_path = false; 1547 initial_slow_test = nullptr; 1548 } 1549 1550 bool allocation_has_use = (alloc->result_cast() != nullptr); 1551 if (!allocation_has_use) { 1552 InitializeNode* init = alloc->initialization(); 1553 if (init != nullptr) { 1554 init->remove(&_igvn); 1555 } 1556 if (expand_fast_path && (initial_slow_test == nullptr)) { 1557 // Remove allocation node and return. 1558 // Size is a non-negative constant -> no initial check needed -> directly to fast path. 1559 // Also, no usages -> empty fast path -> no fall out to slow path -> nothing left. 1560 #ifndef PRODUCT 1561 if (PrintEliminateAllocations) { 1562 tty->print("NotUsed "); 1563 Node* res = alloc->proj_out_or_null(TypeFunc::Parms); 1564 if (res != nullptr) { 1565 res->dump(); 1566 } else { 1567 alloc->dump(); 1568 } 1569 } 1570 #endif 1571 yank_alloc_node(alloc); 1572 return; 1573 } 1574 } 1575 1576 enum { too_big_or_final_path = 1, need_gc_path = 2 }; 1577 Node *slow_region = nullptr; 1578 Node *toobig_false = ctrl; 1579 1580 // generate the initial test if necessary 1581 if (initial_slow_test != nullptr ) { 1582 assert (expand_fast_path, "Only need test if there is a fast path"); 1583 slow_region = new RegionNode(3); 1584 1585 // Now make the initial failure test. Usually a too-big test but 1586 // might be a TRUE for finalizers. 1587 IfNode *toobig_iff = new IfNode(ctrl, initial_slow_test, PROB_MIN, COUNT_UNKNOWN); 1588 transform_later(toobig_iff); 1589 // Plug the failing-too-big test into the slow-path region 1590 Node* toobig_true = new IfTrueNode(toobig_iff); 1591 transform_later(toobig_true); 1592 slow_region ->init_req( too_big_or_final_path, toobig_true ); 1593 toobig_false = new IfFalseNode(toobig_iff); 1594 transform_later(toobig_false); 1595 } else { 1596 // No initial test, just fall into next case 1597 assert(allocation_has_use || !expand_fast_path, "Should already have been handled"); 1598 toobig_false = ctrl; 1599 DEBUG_ONLY(slow_region = NodeSentinel); 1600 } 1601 1602 // If we are here there are several possibilities 1603 // - expand_fast_path is false - then only a slow path is expanded. That's it. 1604 // no_initial_check means a constant allocation. 1605 // - If check always evaluates to false -> expand_fast_path is false (see above) 1606 // - If check always evaluates to true -> directly into fast path (but may bailout to slowpath) 1607 // if !allocation_has_use the fast path is empty 1608 // if !allocation_has_use && no_initial_check 1609 // - Then there are no fastpath that can fall out to slowpath -> no allocation code at all. 1610 // removed by yank_alloc_node above. 1611 1612 Node *slow_mem = mem; // save the current memory state for slow path 1613 // generate the fast allocation code unless we know that the initial test will always go slow 1614 if (expand_fast_path) { 1615 // Fast path modifies only raw memory. 1616 if (mem->is_MergeMem()) { 1617 mem = mem->as_MergeMem()->memory_at(Compile::AliasIdxRaw); 1618 } 1619 1620 // allocate the Region and Phi nodes for the result 1621 result_region = new RegionNode(3); 1622 result_phi_rawmem = new PhiNode(result_region, Type::MEMORY, TypeRawPtr::BOTTOM); 1623 result_phi_i_o = new PhiNode(result_region, Type::ABIO); // I/O is used for Prefetch 1624 1625 // Grab regular I/O before optional prefetch may change it. 1626 // Slow-path does no I/O so just set it to the original I/O. 1627 result_phi_i_o->init_req(slow_result_path, i_o); 1628 1629 // Name successful fast-path variables 1630 Node* fast_oop_ctrl; 1631 Node* fast_oop_rawmem; 1632 1633 if (allocation_has_use) { 1634 Node* needgc_ctrl = nullptr; 1635 result_phi_rawoop = new PhiNode(result_region, TypeRawPtr::BOTTOM); 1636 1637 intx prefetch_lines = length != nullptr ? AllocatePrefetchLines : AllocateInstancePrefetchLines; 1638 BarrierSetC2* bs = BarrierSet::barrier_set()->barrier_set_c2(); 1639 Node* fast_oop = bs->obj_allocate(this, mem, toobig_false, size_in_bytes, i_o, needgc_ctrl, 1640 fast_oop_ctrl, fast_oop_rawmem, 1641 prefetch_lines); 1642 1643 if (initial_slow_test != nullptr) { 1644 // This completes all paths into the slow merge point 1645 slow_region->init_req(need_gc_path, needgc_ctrl); 1646 transform_later(slow_region); 1647 } else { 1648 // No initial slow path needed! 1649 // Just fall from the need-GC path straight into the VM call. 1650 slow_region = needgc_ctrl; 1651 } 1652 1653 InitializeNode* init = alloc->initialization(); 1654 fast_oop_rawmem = initialize_object(alloc, 1655 fast_oop_ctrl, fast_oop_rawmem, fast_oop, 1656 klass_node, length, size_in_bytes); 1657 expand_initialize_membar(alloc, init, fast_oop_ctrl, fast_oop_rawmem); 1658 expand_dtrace_alloc_probe(alloc, fast_oop, fast_oop_ctrl, fast_oop_rawmem); 1659 1660 result_phi_rawoop->init_req(fast_result_path, fast_oop); 1661 } else { 1662 assert (initial_slow_test != nullptr, "sanity"); 1663 fast_oop_ctrl = toobig_false; 1664 fast_oop_rawmem = mem; 1665 transform_later(slow_region); 1666 } 1667 1668 // Plug in the successful fast-path into the result merge point 1669 result_region ->init_req(fast_result_path, fast_oop_ctrl); 1670 result_phi_i_o ->init_req(fast_result_path, i_o); 1671 result_phi_rawmem->init_req(fast_result_path, fast_oop_rawmem); 1672 } else { 1673 slow_region = ctrl; 1674 result_phi_i_o = i_o; // Rename it to use in the following code. 1675 } 1676 1677 // Generate slow-path call 1678 CallNode *call = new CallStaticJavaNode(slow_call_type, slow_call_address, 1679 OptoRuntime::stub_name(slow_call_address), 1680 TypePtr::BOTTOM); 1681 call->init_req(TypeFunc::Control, slow_region); 1682 call->init_req(TypeFunc::I_O, top()); // does no i/o 1683 call->init_req(TypeFunc::Memory, slow_mem); // may gc ptrs 1684 call->init_req(TypeFunc::ReturnAdr, alloc->in(TypeFunc::ReturnAdr)); 1685 call->init_req(TypeFunc::FramePtr, alloc->in(TypeFunc::FramePtr)); 1686 1687 call->init_req(TypeFunc::Parms+0, klass_node); 1688 if (length != nullptr) { 1689 call->init_req(TypeFunc::Parms+1, length); 1690 if (init_val != nullptr) { 1691 call->init_req(TypeFunc::Parms+2, init_val); 1692 } 1693 } else { 1694 // Let the runtime know if this is a larval allocation 1695 call->init_req(TypeFunc::Parms+1, _igvn.intcon(alloc->_larval)); 1696 } 1697 1698 // Copy debug information and adjust JVMState information, then replace 1699 // allocate node with the call 1700 call->copy_call_debug_info(&_igvn, alloc); 1701 // For array allocations, copy the valid length check to the call node so Compile::final_graph_reshaping() can verify 1702 // that the call has the expected number of CatchProj nodes (in case the allocation always fails and the fallthrough 1703 // path dies). 1704 if (valid_length_test != nullptr) { 1705 call->add_req(valid_length_test); 1706 } 1707 if (expand_fast_path) { 1708 call->set_cnt(PROB_UNLIKELY_MAG(4)); // Same effect as RC_UNCOMMON. 1709 } else { 1710 // Hook i_o projection to avoid its elimination during allocation 1711 // replacement (when only a slow call is generated). 1712 call->set_req(TypeFunc::I_O, result_phi_i_o); 1713 } 1714 _igvn.replace_node(alloc, call); 1715 transform_later(call); 1716 1717 // Identify the output projections from the allocate node and 1718 // adjust any references to them. 1719 // The control and io projections look like: 1720 // 1721 // v---Proj(ctrl) <-----+ v---CatchProj(ctrl) 1722 // Allocate Catch 1723 // ^---Proj(io) <-------+ ^---CatchProj(io) 1724 // 1725 // We are interested in the CatchProj nodes. 1726 // 1727 _callprojs = call->extract_projections(false /*separate_io_proj*/, false /*do_asserts*/); 1728 1729 // An allocate node has separate memory projections for the uses on 1730 // the control and i_o paths. Replace the control memory projection with 1731 // result_phi_rawmem (unless we are only generating a slow call when 1732 // both memory projections are combined) 1733 if (expand_fast_path && _callprojs->fallthrough_memproj != nullptr) { 1734 _igvn.replace_in_uses(_callprojs->fallthrough_memproj, result_phi_rawmem); 1735 } 1736 // Now change uses of catchall_memproj to use fallthrough_memproj and delete 1737 // catchall_memproj so we end up with a call that has only 1 memory projection. 1738 if (_callprojs->catchall_memproj != nullptr) { 1739 if (_callprojs->fallthrough_memproj == nullptr) { 1740 _callprojs->fallthrough_memproj = new ProjNode(call, TypeFunc::Memory); 1741 transform_later(_callprojs->fallthrough_memproj); 1742 } 1743 _igvn.replace_in_uses(_callprojs->catchall_memproj, _callprojs->fallthrough_memproj); 1744 _igvn.remove_dead_node(_callprojs->catchall_memproj); 1745 } 1746 1747 // An allocate node has separate i_o projections for the uses on the control 1748 // and i_o paths. Always replace the control i_o projection with result i_o 1749 // otherwise incoming i_o become dead when only a slow call is generated 1750 // (it is different from memory projections where both projections are 1751 // combined in such case). 1752 if (_callprojs->fallthrough_ioproj != nullptr) { 1753 _igvn.replace_in_uses(_callprojs->fallthrough_ioproj, result_phi_i_o); 1754 } 1755 // Now change uses of catchall_ioproj to use fallthrough_ioproj and delete 1756 // catchall_ioproj so we end up with a call that has only 1 i_o projection. 1757 if (_callprojs->catchall_ioproj != nullptr) { 1758 if (_callprojs->fallthrough_ioproj == nullptr) { 1759 _callprojs->fallthrough_ioproj = new ProjNode(call, TypeFunc::I_O); 1760 transform_later(_callprojs->fallthrough_ioproj); 1761 } 1762 _igvn.replace_in_uses(_callprojs->catchall_ioproj, _callprojs->fallthrough_ioproj); 1763 _igvn.remove_dead_node(_callprojs->catchall_ioproj); 1764 } 1765 1766 // if we generated only a slow call, we are done 1767 if (!expand_fast_path) { 1768 // Now we can unhook i_o. 1769 if (result_phi_i_o->outcnt() > 1) { 1770 call->set_req(TypeFunc::I_O, top()); 1771 } else { 1772 assert(result_phi_i_o->unique_ctrl_out() == call, "sanity"); 1773 // Case of new array with negative size known during compilation. 1774 // AllocateArrayNode::Ideal() optimization disconnect unreachable 1775 // following code since call to runtime will throw exception. 1776 // As result there will be no users of i_o after the call. 1777 // Leave i_o attached to this call to avoid problems in preceding graph. 1778 } 1779 return; 1780 } 1781 1782 if (_callprojs->fallthrough_catchproj != nullptr) { 1783 ctrl = _callprojs->fallthrough_catchproj->clone(); 1784 transform_later(ctrl); 1785 _igvn.replace_node(_callprojs->fallthrough_catchproj, result_region); 1786 } else { 1787 ctrl = top(); 1788 } 1789 Node *slow_result; 1790 if (_callprojs->resproj[0] == nullptr) { 1791 // no uses of the allocation result 1792 slow_result = top(); 1793 } else { 1794 slow_result = _callprojs->resproj[0]->clone(); 1795 transform_later(slow_result); 1796 _igvn.replace_node(_callprojs->resproj[0], result_phi_rawoop); 1797 } 1798 1799 // Plug slow-path into result merge point 1800 result_region->init_req( slow_result_path, ctrl); 1801 transform_later(result_region); 1802 if (allocation_has_use) { 1803 result_phi_rawoop->init_req(slow_result_path, slow_result); 1804 transform_later(result_phi_rawoop); 1805 } 1806 result_phi_rawmem->init_req(slow_result_path, _callprojs->fallthrough_memproj); 1807 transform_later(result_phi_rawmem); 1808 transform_later(result_phi_i_o); 1809 // This completes all paths into the result merge point 1810 } 1811 1812 // Remove alloc node that has no uses. 1813 void PhaseMacroExpand::yank_alloc_node(AllocateNode* alloc) { 1814 Node* ctrl = alloc->in(TypeFunc::Control); 1815 Node* mem = alloc->in(TypeFunc::Memory); 1816 Node* i_o = alloc->in(TypeFunc::I_O); 1817 1818 _callprojs = alloc->extract_projections(false /*separate_io_proj*/, false /*do_asserts*/); 1819 if (_callprojs->resproj[0] != nullptr) { 1820 for (DUIterator_Fast imax, i = _callprojs->resproj[0]->fast_outs(imax); i < imax; i++) { 1821 Node* use = _callprojs->resproj[0]->fast_out(i); 1822 use->isa_MemBar()->remove(&_igvn); 1823 --imax; 1824 --i; // back up iterator 1825 } 1826 assert(_callprojs->resproj[0]->outcnt() == 0, "all uses must be deleted"); 1827 _igvn.remove_dead_node(_callprojs->resproj[0]); 1828 } 1829 if (_callprojs->fallthrough_catchproj != nullptr) { 1830 _igvn.replace_in_uses(_callprojs->fallthrough_catchproj, ctrl); 1831 _igvn.remove_dead_node(_callprojs->fallthrough_catchproj); 1832 } 1833 if (_callprojs->catchall_catchproj != nullptr) { 1834 _igvn.rehash_node_delayed(_callprojs->catchall_catchproj); 1835 _callprojs->catchall_catchproj->set_req(0, top()); 1836 } 1837 if (_callprojs->fallthrough_proj != nullptr) { 1838 Node* catchnode = _callprojs->fallthrough_proj->unique_ctrl_out(); 1839 _igvn.remove_dead_node(catchnode); 1840 _igvn.remove_dead_node(_callprojs->fallthrough_proj); 1841 } 1842 if (_callprojs->fallthrough_memproj != nullptr) { 1843 _igvn.replace_in_uses(_callprojs->fallthrough_memproj, mem); 1844 _igvn.remove_dead_node(_callprojs->fallthrough_memproj); 1845 } 1846 if (_callprojs->fallthrough_ioproj != nullptr) { 1847 _igvn.replace_in_uses(_callprojs->fallthrough_ioproj, i_o); 1848 _igvn.remove_dead_node(_callprojs->fallthrough_ioproj); 1849 } 1850 if (_callprojs->catchall_memproj != nullptr) { 1851 _igvn.rehash_node_delayed(_callprojs->catchall_memproj); 1852 _callprojs->catchall_memproj->set_req(0, top()); 1853 } 1854 if (_callprojs->catchall_ioproj != nullptr) { 1855 _igvn.rehash_node_delayed(_callprojs->catchall_ioproj); 1856 _callprojs->catchall_ioproj->set_req(0, top()); 1857 } 1858 #ifndef PRODUCT 1859 if (PrintEliminateAllocations) { 1860 if (alloc->is_AllocateArray()) { 1861 tty->print_cr("++++ Eliminated: %d AllocateArray", alloc->_idx); 1862 } else { 1863 tty->print_cr("++++ Eliminated: %d Allocate", alloc->_idx); 1864 } 1865 } 1866 #endif 1867 _igvn.remove_dead_node(alloc); 1868 } 1869 1870 void PhaseMacroExpand::expand_initialize_membar(AllocateNode* alloc, InitializeNode* init, 1871 Node*& fast_oop_ctrl, Node*& fast_oop_rawmem) { 1872 // If initialization is performed by an array copy, any required 1873 // MemBarStoreStore was already added. If the object does not 1874 // escape no need for a MemBarStoreStore. If the object does not 1875 // escape in its initializer and memory barrier (MemBarStoreStore or 1876 // stronger) is already added at exit of initializer, also no need 1877 // for a MemBarStoreStore. Otherwise we need a MemBarStoreStore 1878 // so that stores that initialize this object can't be reordered 1879 // with a subsequent store that makes this object accessible by 1880 // other threads. 1881 // Other threads include java threads and JVM internal threads 1882 // (for example concurrent GC threads). Current concurrent GC 1883 // implementation: G1 will not scan newly created object, 1884 // so it's safe to skip storestore barrier when allocation does 1885 // not escape. 1886 if (!alloc->does_not_escape_thread() && 1887 !alloc->is_allocation_MemBar_redundant() && 1888 (init == nullptr || !init->is_complete_with_arraycopy())) { 1889 if (init == nullptr || init->req() < InitializeNode::RawStores) { 1890 // No InitializeNode or no stores captured by zeroing 1891 // elimination. Simply add the MemBarStoreStore after object 1892 // initialization. 1893 MemBarNode* mb = MemBarNode::make(C, Op_MemBarStoreStore, Compile::AliasIdxBot); 1894 transform_later(mb); 1895 1896 mb->init_req(TypeFunc::Memory, fast_oop_rawmem); 1897 mb->init_req(TypeFunc::Control, fast_oop_ctrl); 1898 fast_oop_ctrl = new ProjNode(mb, TypeFunc::Control); 1899 transform_later(fast_oop_ctrl); 1900 fast_oop_rawmem = new ProjNode(mb, TypeFunc::Memory); 1901 transform_later(fast_oop_rawmem); 1902 } else { 1903 // Add the MemBarStoreStore after the InitializeNode so that 1904 // all stores performing the initialization that were moved 1905 // before the InitializeNode happen before the storestore 1906 // barrier. 1907 1908 Node* init_ctrl = init->proj_out_or_null(TypeFunc::Control); 1909 Node* init_mem = init->proj_out_or_null(TypeFunc::Memory); 1910 1911 MemBarNode* mb = MemBarNode::make(C, Op_MemBarStoreStore, Compile::AliasIdxBot); 1912 transform_later(mb); 1913 1914 Node* ctrl = new ProjNode(init, TypeFunc::Control); 1915 transform_later(ctrl); 1916 Node* mem = new ProjNode(init, TypeFunc::Memory); 1917 transform_later(mem); 1918 1919 // The MemBarStoreStore depends on control and memory coming 1920 // from the InitializeNode 1921 mb->init_req(TypeFunc::Memory, mem); 1922 mb->init_req(TypeFunc::Control, ctrl); 1923 1924 ctrl = new ProjNode(mb, TypeFunc::Control); 1925 transform_later(ctrl); 1926 mem = new ProjNode(mb, TypeFunc::Memory); 1927 transform_later(mem); 1928 1929 // All nodes that depended on the InitializeNode for control 1930 // and memory must now depend on the MemBarNode that itself 1931 // depends on the InitializeNode 1932 if (init_ctrl != nullptr) { 1933 _igvn.replace_node(init_ctrl, ctrl); 1934 } 1935 if (init_mem != nullptr) { 1936 _igvn.replace_node(init_mem, mem); 1937 } 1938 } 1939 } 1940 } 1941 1942 void PhaseMacroExpand::expand_dtrace_alloc_probe(AllocateNode* alloc, Node* oop, 1943 Node*& ctrl, Node*& rawmem) { 1944 if (C->env()->dtrace_alloc_probes()) { 1945 // Slow-path call 1946 int size = TypeFunc::Parms + 2; 1947 CallLeafNode *call = new CallLeafNode(OptoRuntime::dtrace_object_alloc_Type(), 1948 CAST_FROM_FN_PTR(address, 1949 static_cast<int (*)(JavaThread*, oopDesc*)>(SharedRuntime::dtrace_object_alloc)), 1950 "dtrace_object_alloc", 1951 TypeRawPtr::BOTTOM); 1952 1953 // Get base of thread-local storage area 1954 Node* thread = new ThreadLocalNode(); 1955 transform_later(thread); 1956 1957 call->init_req(TypeFunc::Parms + 0, thread); 1958 call->init_req(TypeFunc::Parms + 1, oop); 1959 call->init_req(TypeFunc::Control, ctrl); 1960 call->init_req(TypeFunc::I_O , top()); // does no i/o 1961 call->init_req(TypeFunc::Memory , rawmem); 1962 call->init_req(TypeFunc::ReturnAdr, alloc->in(TypeFunc::ReturnAdr)); 1963 call->init_req(TypeFunc::FramePtr, alloc->in(TypeFunc::FramePtr)); 1964 transform_later(call); 1965 ctrl = new ProjNode(call, TypeFunc::Control); 1966 transform_later(ctrl); 1967 rawmem = new ProjNode(call, TypeFunc::Memory); 1968 transform_later(rawmem); 1969 } 1970 } 1971 1972 // Helper for PhaseMacroExpand::expand_allocate_common. 1973 // Initializes the newly-allocated storage. 1974 Node* PhaseMacroExpand::initialize_object(AllocateNode* alloc, 1975 Node* control, Node* rawmem, Node* object, 1976 Node* klass_node, Node* length, 1977 Node* size_in_bytes) { 1978 InitializeNode* init = alloc->initialization(); 1979 // Store the klass & mark bits 1980 Node* mark_node = alloc->make_ideal_mark(&_igvn, control, rawmem); 1981 if (!mark_node->is_Con()) { 1982 transform_later(mark_node); 1983 } 1984 rawmem = make_store(control, rawmem, object, oopDesc::mark_offset_in_bytes(), mark_node, TypeX_X->basic_type()); 1985 1986 if (!UseCompactObjectHeaders) { 1987 rawmem = make_store(control, rawmem, object, oopDesc::klass_offset_in_bytes(), klass_node, T_METADATA); 1988 } 1989 int header_size = alloc->minimum_header_size(); // conservatively small 1990 1991 // Array length 1992 if (length != nullptr) { // Arrays need length field 1993 rawmem = make_store(control, rawmem, object, arrayOopDesc::length_offset_in_bytes(), length, T_INT); 1994 // conservatively small header size: 1995 header_size = arrayOopDesc::base_offset_in_bytes(T_BYTE); 1996 if (_igvn.type(klass_node)->isa_aryklassptr()) { // we know the exact header size in most cases: 1997 BasicType elem = _igvn.type(klass_node)->is_klassptr()->as_instance_type()->isa_aryptr()->elem()->array_element_basic_type(); 1998 if (is_reference_type(elem, true)) { 1999 elem = T_OBJECT; 2000 } 2001 header_size = Klass::layout_helper_header_size(Klass::array_layout_helper(elem)); 2002 } 2003 } 2004 2005 // Clear the object body, if necessary. 2006 if (init == nullptr) { 2007 // The init has somehow disappeared; be cautious and clear everything. 2008 // 2009 // This can happen if a node is allocated but an uncommon trap occurs 2010 // immediately. In this case, the Initialize gets associated with the 2011 // trap, and may be placed in a different (outer) loop, if the Allocate 2012 // is in a loop. If (this is rare) the inner loop gets unrolled, then 2013 // there can be two Allocates to one Initialize. The answer in all these 2014 // edge cases is safety first. It is always safe to clear immediately 2015 // within an Allocate, and then (maybe or maybe not) clear some more later. 2016 if (!(UseTLAB && ZeroTLAB)) { 2017 rawmem = ClearArrayNode::clear_memory(control, rawmem, object, 2018 alloc->in(AllocateNode::InitValue), 2019 alloc->in(AllocateNode::RawInitValue), 2020 header_size, size_in_bytes, 2021 &_igvn); 2022 } 2023 } else { 2024 if (!init->is_complete()) { 2025 // Try to win by zeroing only what the init does not store. 2026 // We can also try to do some peephole optimizations, 2027 // such as combining some adjacent subword stores. 2028 rawmem = init->complete_stores(control, rawmem, object, 2029 header_size, size_in_bytes, &_igvn); 2030 } 2031 // We have no more use for this link, since the AllocateNode goes away: 2032 init->set_req(InitializeNode::RawAddress, top()); 2033 // (If we keep the link, it just confuses the register allocator, 2034 // who thinks he sees a real use of the address by the membar.) 2035 } 2036 2037 return rawmem; 2038 } 2039 2040 // Generate prefetch instructions for next allocations. 2041 Node* PhaseMacroExpand::prefetch_allocation(Node* i_o, Node*& needgc_false, 2042 Node*& contended_phi_rawmem, 2043 Node* old_eden_top, Node* new_eden_top, 2044 intx lines) { 2045 enum { fall_in_path = 1, pf_path = 2 }; 2046 if( UseTLAB && AllocatePrefetchStyle == 2 ) { 2047 // Generate prefetch allocation with watermark check. 2048 // As an allocation hits the watermark, we will prefetch starting 2049 // at a "distance" away from watermark. 2050 2051 Node *pf_region = new RegionNode(3); 2052 Node *pf_phi_rawmem = new PhiNode( pf_region, Type::MEMORY, 2053 TypeRawPtr::BOTTOM ); 2054 // I/O is used for Prefetch 2055 Node *pf_phi_abio = new PhiNode( pf_region, Type::ABIO ); 2056 2057 Node *thread = new ThreadLocalNode(); 2058 transform_later(thread); 2059 2060 Node *eden_pf_adr = new AddPNode( top()/*not oop*/, thread, 2061 _igvn.MakeConX(in_bytes(JavaThread::tlab_pf_top_offset())) ); 2062 transform_later(eden_pf_adr); 2063 2064 Node *old_pf_wm = new LoadPNode(needgc_false, 2065 contended_phi_rawmem, eden_pf_adr, 2066 TypeRawPtr::BOTTOM, TypeRawPtr::BOTTOM, 2067 MemNode::unordered); 2068 transform_later(old_pf_wm); 2069 2070 // check against new_eden_top 2071 Node *need_pf_cmp = new CmpPNode( new_eden_top, old_pf_wm ); 2072 transform_later(need_pf_cmp); 2073 Node *need_pf_bol = new BoolNode( need_pf_cmp, BoolTest::ge ); 2074 transform_later(need_pf_bol); 2075 IfNode *need_pf_iff = new IfNode( needgc_false, need_pf_bol, 2076 PROB_UNLIKELY_MAG(4), COUNT_UNKNOWN ); 2077 transform_later(need_pf_iff); 2078 2079 // true node, add prefetchdistance 2080 Node *need_pf_true = new IfTrueNode( need_pf_iff ); 2081 transform_later(need_pf_true); 2082 2083 Node *need_pf_false = new IfFalseNode( need_pf_iff ); 2084 transform_later(need_pf_false); 2085 2086 Node *new_pf_wmt = new AddPNode( top(), old_pf_wm, 2087 _igvn.MakeConX(AllocatePrefetchDistance) ); 2088 transform_later(new_pf_wmt ); 2089 new_pf_wmt->set_req(0, need_pf_true); 2090 2091 Node *store_new_wmt = new StorePNode(need_pf_true, 2092 contended_phi_rawmem, eden_pf_adr, 2093 TypeRawPtr::BOTTOM, new_pf_wmt, 2094 MemNode::unordered); 2095 transform_later(store_new_wmt); 2096 2097 // adding prefetches 2098 pf_phi_abio->init_req( fall_in_path, i_o ); 2099 2100 Node *prefetch_adr; 2101 Node *prefetch; 2102 uint step_size = AllocatePrefetchStepSize; 2103 uint distance = 0; 2104 2105 for ( intx i = 0; i < lines; i++ ) { 2106 prefetch_adr = new AddPNode( old_pf_wm, new_pf_wmt, 2107 _igvn.MakeConX(distance) ); 2108 transform_later(prefetch_adr); 2109 prefetch = new PrefetchAllocationNode( i_o, prefetch_adr ); 2110 transform_later(prefetch); 2111 distance += step_size; 2112 i_o = prefetch; 2113 } 2114 pf_phi_abio->set_req( pf_path, i_o ); 2115 2116 pf_region->init_req( fall_in_path, need_pf_false ); 2117 pf_region->init_req( pf_path, need_pf_true ); 2118 2119 pf_phi_rawmem->init_req( fall_in_path, contended_phi_rawmem ); 2120 pf_phi_rawmem->init_req( pf_path, store_new_wmt ); 2121 2122 transform_later(pf_region); 2123 transform_later(pf_phi_rawmem); 2124 transform_later(pf_phi_abio); 2125 2126 needgc_false = pf_region; 2127 contended_phi_rawmem = pf_phi_rawmem; 2128 i_o = pf_phi_abio; 2129 } else if( UseTLAB && AllocatePrefetchStyle == 3 ) { 2130 // Insert a prefetch instruction for each allocation. 2131 // This code is used to generate 1 prefetch instruction per cache line. 2132 2133 // Generate several prefetch instructions. 2134 uint step_size = AllocatePrefetchStepSize; 2135 uint distance = AllocatePrefetchDistance; 2136 2137 // Next cache address. 2138 Node *cache_adr = new AddPNode(old_eden_top, old_eden_top, 2139 _igvn.MakeConX(step_size + distance)); 2140 transform_later(cache_adr); 2141 cache_adr = new CastP2XNode(needgc_false, cache_adr); 2142 transform_later(cache_adr); 2143 // Address is aligned to execute prefetch to the beginning of cache line size 2144 // (it is important when BIS instruction is used on SPARC as prefetch). 2145 Node* mask = _igvn.MakeConX(~(intptr_t)(step_size-1)); 2146 cache_adr = new AndXNode(cache_adr, mask); 2147 transform_later(cache_adr); 2148 cache_adr = new CastX2PNode(cache_adr); 2149 transform_later(cache_adr); 2150 2151 // Prefetch 2152 Node *prefetch = new PrefetchAllocationNode( contended_phi_rawmem, cache_adr ); 2153 prefetch->set_req(0, needgc_false); 2154 transform_later(prefetch); 2155 contended_phi_rawmem = prefetch; 2156 Node *prefetch_adr; 2157 distance = step_size; 2158 for ( intx i = 1; i < lines; i++ ) { 2159 prefetch_adr = new AddPNode( cache_adr, cache_adr, 2160 _igvn.MakeConX(distance) ); 2161 transform_later(prefetch_adr); 2162 prefetch = new PrefetchAllocationNode( contended_phi_rawmem, prefetch_adr ); 2163 transform_later(prefetch); 2164 distance += step_size; 2165 contended_phi_rawmem = prefetch; 2166 } 2167 } else if( AllocatePrefetchStyle > 0 ) { 2168 // Insert a prefetch for each allocation only on the fast-path 2169 Node *prefetch_adr; 2170 Node *prefetch; 2171 // Generate several prefetch instructions. 2172 uint step_size = AllocatePrefetchStepSize; 2173 uint distance = AllocatePrefetchDistance; 2174 for ( intx i = 0; i < lines; i++ ) { 2175 prefetch_adr = new AddPNode( old_eden_top, new_eden_top, 2176 _igvn.MakeConX(distance) ); 2177 transform_later(prefetch_adr); 2178 prefetch = new PrefetchAllocationNode( i_o, prefetch_adr ); 2179 // Do not let it float too high, since if eden_top == eden_end, 2180 // both might be null. 2181 if( i == 0 ) { // Set control for first prefetch, next follows it 2182 prefetch->init_req(0, needgc_false); 2183 } 2184 transform_later(prefetch); 2185 distance += step_size; 2186 i_o = prefetch; 2187 } 2188 } 2189 return i_o; 2190 } 2191 2192 2193 void PhaseMacroExpand::expand_allocate(AllocateNode *alloc) { 2194 expand_allocate_common(alloc, nullptr, nullptr, 2195 OptoRuntime::new_instance_Type(), 2196 OptoRuntime::new_instance_Java(), nullptr); 2197 } 2198 2199 void PhaseMacroExpand::expand_allocate_array(AllocateArrayNode *alloc) { 2200 Node* length = alloc->in(AllocateNode::ALength); 2201 Node* valid_length_test = alloc->in(AllocateNode::ValidLengthTest); 2202 InitializeNode* init = alloc->initialization(); 2203 Node* klass_node = alloc->in(AllocateNode::KlassNode); 2204 Node* init_value = alloc->in(AllocateNode::InitValue); 2205 const TypeAryKlassPtr* ary_klass_t = _igvn.type(klass_node)->isa_aryklassptr(); 2206 // TODO 8366668 Compute the VM type, is this even needed now that we set it earlier? Should we assert instead? 2207 if (ary_klass_t && ary_klass_t->klass_is_exact() && ary_klass_t->exact_klass()->is_obj_array_klass()) { 2208 ary_klass_t = ary_klass_t->get_vm_type(); 2209 klass_node = makecon(ary_klass_t); 2210 _igvn.replace_input_of(alloc, AllocateNode::KlassNode, klass_node); 2211 } 2212 const TypeFunc* slow_call_type; 2213 address slow_call_address; // Address of slow call 2214 if (init != nullptr && init->is_complete_with_arraycopy() && 2215 ary_klass_t && ary_klass_t->elem()->isa_klassptr() == nullptr) { 2216 // Don't zero type array during slow allocation in VM since 2217 // it will be initialized later by arraycopy in compiled code. 2218 slow_call_address = OptoRuntime::new_array_nozero_Java(); 2219 slow_call_type = OptoRuntime::new_array_nozero_Type(); 2220 } else { 2221 slow_call_address = OptoRuntime::new_array_Java(); 2222 slow_call_type = OptoRuntime::new_array_Type(); 2223 2224 if (init_value == nullptr) { 2225 init_value = _igvn.zerocon(T_OBJECT); 2226 } else if (UseCompressedOops) { 2227 init_value = transform_later(new DecodeNNode(init_value, init_value->bottom_type()->make_ptr())); 2228 } 2229 } 2230 expand_allocate_common(alloc, length, init_value, 2231 slow_call_type, 2232 slow_call_address, valid_length_test); 2233 } 2234 2235 //-------------------mark_eliminated_box---------------------------------- 2236 // 2237 // During EA obj may point to several objects but after few ideal graph 2238 // transformations (CCP) it may point to only one non escaping object 2239 // (but still using phi), corresponding locks and unlocks will be marked 2240 // for elimination. Later obj could be replaced with a new node (new phi) 2241 // and which does not have escape information. And later after some graph 2242 // reshape other locks and unlocks (which were not marked for elimination 2243 // before) are connected to this new obj (phi) but they still will not be 2244 // marked for elimination since new obj has no escape information. 2245 // Mark all associated (same box and obj) lock and unlock nodes for 2246 // elimination if some of them marked already. 2247 void PhaseMacroExpand::mark_eliminated_box(Node* box, Node* obj) { 2248 BoxLockNode* oldbox = box->as_BoxLock(); 2249 if (oldbox->is_eliminated()) { 2250 return; // This BoxLock node was processed already. 2251 } 2252 assert(!oldbox->is_unbalanced(), "this should not be called for unbalanced region"); 2253 // New implementation (EliminateNestedLocks) has separate BoxLock 2254 // node for each locked region so mark all associated locks/unlocks as 2255 // eliminated even if different objects are referenced in one locked region 2256 // (for example, OSR compilation of nested loop inside locked scope). 2257 if (EliminateNestedLocks || 2258 oldbox->as_BoxLock()->is_simple_lock_region(nullptr, obj, nullptr)) { 2259 // Box is used only in one lock region. Mark this box as eliminated. 2260 oldbox->set_local(); // This verifies correct state of BoxLock 2261 _igvn.hash_delete(oldbox); 2262 oldbox->set_eliminated(); // This changes box's hash value 2263 _igvn.hash_insert(oldbox); 2264 2265 for (uint i = 0; i < oldbox->outcnt(); i++) { 2266 Node* u = oldbox->raw_out(i); 2267 if (u->is_AbstractLock() && !u->as_AbstractLock()->is_non_esc_obj()) { 2268 AbstractLockNode* alock = u->as_AbstractLock(); 2269 // Check lock's box since box could be referenced by Lock's debug info. 2270 if (alock->box_node() == oldbox) { 2271 // Mark eliminated all related locks and unlocks. 2272 #ifdef ASSERT 2273 alock->log_lock_optimization(C, "eliminate_lock_set_non_esc4"); 2274 #endif 2275 alock->set_non_esc_obj(); 2276 } 2277 } 2278 } 2279 return; 2280 } 2281 2282 // Create new "eliminated" BoxLock node and use it in monitor debug info 2283 // instead of oldbox for the same object. 2284 BoxLockNode* newbox = oldbox->clone()->as_BoxLock(); 2285 2286 // Note: BoxLock node is marked eliminated only here and it is used 2287 // to indicate that all associated lock and unlock nodes are marked 2288 // for elimination. 2289 newbox->set_local(); // This verifies correct state of BoxLock 2290 newbox->set_eliminated(); 2291 transform_later(newbox); 2292 2293 // Replace old box node with new box for all users of the same object. 2294 for (uint i = 0; i < oldbox->outcnt();) { 2295 bool next_edge = true; 2296 2297 Node* u = oldbox->raw_out(i); 2298 if (u->is_AbstractLock()) { 2299 AbstractLockNode* alock = u->as_AbstractLock(); 2300 if (alock->box_node() == oldbox && alock->obj_node()->eqv_uncast(obj)) { 2301 // Replace Box and mark eliminated all related locks and unlocks. 2302 #ifdef ASSERT 2303 alock->log_lock_optimization(C, "eliminate_lock_set_non_esc5"); 2304 #endif 2305 alock->set_non_esc_obj(); 2306 _igvn.rehash_node_delayed(alock); 2307 alock->set_box_node(newbox); 2308 next_edge = false; 2309 } 2310 } 2311 if (u->is_FastLock() && u->as_FastLock()->obj_node()->eqv_uncast(obj)) { 2312 FastLockNode* flock = u->as_FastLock(); 2313 assert(flock->box_node() == oldbox, "sanity"); 2314 _igvn.rehash_node_delayed(flock); 2315 flock->set_box_node(newbox); 2316 next_edge = false; 2317 } 2318 2319 // Replace old box in monitor debug info. 2320 if (u->is_SafePoint() && u->as_SafePoint()->jvms()) { 2321 SafePointNode* sfn = u->as_SafePoint(); 2322 JVMState* youngest_jvms = sfn->jvms(); 2323 int max_depth = youngest_jvms->depth(); 2324 for (int depth = 1; depth <= max_depth; depth++) { 2325 JVMState* jvms = youngest_jvms->of_depth(depth); 2326 int num_mon = jvms->nof_monitors(); 2327 // Loop over monitors 2328 for (int idx = 0; idx < num_mon; idx++) { 2329 Node* obj_node = sfn->monitor_obj(jvms, idx); 2330 Node* box_node = sfn->monitor_box(jvms, idx); 2331 if (box_node == oldbox && obj_node->eqv_uncast(obj)) { 2332 int j = jvms->monitor_box_offset(idx); 2333 _igvn.replace_input_of(u, j, newbox); 2334 next_edge = false; 2335 } 2336 } 2337 } 2338 } 2339 if (next_edge) i++; 2340 } 2341 } 2342 2343 //-----------------------mark_eliminated_locking_nodes----------------------- 2344 void PhaseMacroExpand::mark_eliminated_locking_nodes(AbstractLockNode *alock) { 2345 if (!alock->is_balanced()) { 2346 return; // Can't do any more elimination for this locking region 2347 } 2348 if (EliminateNestedLocks) { 2349 if (alock->is_nested()) { 2350 assert(alock->box_node()->as_BoxLock()->is_eliminated(), "sanity"); 2351 return; 2352 } else if (!alock->is_non_esc_obj()) { // Not eliminated or coarsened 2353 // Only Lock node has JVMState needed here. 2354 // Not that preceding claim is documented anywhere else. 2355 if (alock->jvms() != nullptr) { 2356 if (alock->as_Lock()->is_nested_lock_region()) { 2357 // Mark eliminated related nested locks and unlocks. 2358 Node* obj = alock->obj_node(); 2359 BoxLockNode* box_node = alock->box_node()->as_BoxLock(); 2360 assert(!box_node->is_eliminated(), "should not be marked yet"); 2361 // Note: BoxLock node is marked eliminated only here 2362 // and it is used to indicate that all associated lock 2363 // and unlock nodes are marked for elimination. 2364 box_node->set_eliminated(); // Box's hash is always NO_HASH here 2365 for (uint i = 0; i < box_node->outcnt(); i++) { 2366 Node* u = box_node->raw_out(i); 2367 if (u->is_AbstractLock()) { 2368 alock = u->as_AbstractLock(); 2369 if (alock->box_node() == box_node) { 2370 // Verify that this Box is referenced only by related locks. 2371 assert(alock->obj_node()->eqv_uncast(obj), ""); 2372 // Mark all related locks and unlocks. 2373 #ifdef ASSERT 2374 alock->log_lock_optimization(C, "eliminate_lock_set_nested"); 2375 #endif 2376 alock->set_nested(); 2377 } 2378 } 2379 } 2380 } else { 2381 #ifdef ASSERT 2382 alock->log_lock_optimization(C, "eliminate_lock_NOT_nested_lock_region"); 2383 if (C->log() != nullptr) 2384 alock->as_Lock()->is_nested_lock_region(C); // rerun for debugging output 2385 #endif 2386 } 2387 } 2388 return; 2389 } 2390 // Process locks for non escaping object 2391 assert(alock->is_non_esc_obj(), ""); 2392 } // EliminateNestedLocks 2393 2394 if (alock->is_non_esc_obj()) { // Lock is used for non escaping object 2395 // Look for all locks of this object and mark them and 2396 // corresponding BoxLock nodes as eliminated. 2397 Node* obj = alock->obj_node(); 2398 for (uint j = 0; j < obj->outcnt(); j++) { 2399 Node* o = obj->raw_out(j); 2400 if (o->is_AbstractLock() && 2401 o->as_AbstractLock()->obj_node()->eqv_uncast(obj)) { 2402 alock = o->as_AbstractLock(); 2403 Node* box = alock->box_node(); 2404 // Replace old box node with new eliminated box for all users 2405 // of the same object and mark related locks as eliminated. 2406 mark_eliminated_box(box, obj); 2407 } 2408 } 2409 } 2410 } 2411 2412 // we have determined that this lock/unlock can be eliminated, we simply 2413 // eliminate the node without expanding it. 2414 // 2415 // Note: The membar's associated with the lock/unlock are currently not 2416 // eliminated. This should be investigated as a future enhancement. 2417 // 2418 bool PhaseMacroExpand::eliminate_locking_node(AbstractLockNode *alock) { 2419 2420 if (!alock->is_eliminated()) { 2421 return false; 2422 } 2423 #ifdef ASSERT 2424 if (!alock->is_coarsened()) { 2425 // Check that new "eliminated" BoxLock node is created. 2426 BoxLockNode* oldbox = alock->box_node()->as_BoxLock(); 2427 assert(oldbox->is_eliminated(), "should be done already"); 2428 } 2429 #endif 2430 2431 alock->log_lock_optimization(C, "eliminate_lock"); 2432 2433 #ifndef PRODUCT 2434 if (PrintEliminateLocks) { 2435 tty->print_cr("++++ Eliminated: %d %s '%s'", alock->_idx, (alock->is_Lock() ? "Lock" : "Unlock"), alock->kind_as_string()); 2436 } 2437 #endif 2438 2439 Node* mem = alock->in(TypeFunc::Memory); 2440 Node* ctrl = alock->in(TypeFunc::Control); 2441 guarantee(ctrl != nullptr, "missing control projection, cannot replace_node() with null"); 2442 2443 _callprojs = alock->extract_projections(false /*separate_io_proj*/, false /*do_asserts*/); 2444 // There are 2 projections from the lock. The lock node will 2445 // be deleted when its last use is subsumed below. 2446 assert(alock->outcnt() == 2 && 2447 _callprojs->fallthrough_proj != nullptr && 2448 _callprojs->fallthrough_memproj != nullptr, 2449 "Unexpected projections from Lock/Unlock"); 2450 2451 Node* fallthroughproj = _callprojs->fallthrough_proj; 2452 Node* memproj_fallthrough = _callprojs->fallthrough_memproj; 2453 2454 // The memory projection from a lock/unlock is RawMem 2455 // The input to a Lock is merged memory, so extract its RawMem input 2456 // (unless the MergeMem has been optimized away.) 2457 if (alock->is_Lock()) { 2458 // Search for MemBarAcquireLock node and delete it also. 2459 MemBarNode* membar = fallthroughproj->unique_ctrl_out()->as_MemBar(); 2460 assert(membar != nullptr && membar->Opcode() == Op_MemBarAcquireLock, ""); 2461 Node* ctrlproj = membar->proj_out(TypeFunc::Control); 2462 Node* memproj = membar->proj_out(TypeFunc::Memory); 2463 _igvn.replace_node(ctrlproj, fallthroughproj); 2464 _igvn.replace_node(memproj, memproj_fallthrough); 2465 2466 // Delete FastLock node also if this Lock node is unique user 2467 // (a loop peeling may clone a Lock node). 2468 Node* flock = alock->as_Lock()->fastlock_node(); 2469 if (flock->outcnt() == 1) { 2470 assert(flock->unique_out() == alock, "sanity"); 2471 _igvn.replace_node(flock, top()); 2472 } 2473 } 2474 2475 // Search for MemBarReleaseLock node and delete it also. 2476 if (alock->is_Unlock() && ctrl->is_Proj() && ctrl->in(0)->is_MemBar()) { 2477 MemBarNode* membar = ctrl->in(0)->as_MemBar(); 2478 assert(membar->Opcode() == Op_MemBarReleaseLock && 2479 mem->is_Proj() && membar == mem->in(0), ""); 2480 _igvn.replace_node(fallthroughproj, ctrl); 2481 _igvn.replace_node(memproj_fallthrough, mem); 2482 fallthroughproj = ctrl; 2483 memproj_fallthrough = mem; 2484 ctrl = membar->in(TypeFunc::Control); 2485 mem = membar->in(TypeFunc::Memory); 2486 } 2487 2488 _igvn.replace_node(fallthroughproj, ctrl); 2489 _igvn.replace_node(memproj_fallthrough, mem); 2490 return true; 2491 } 2492 2493 2494 //------------------------------expand_lock_node---------------------- 2495 void PhaseMacroExpand::expand_lock_node(LockNode *lock) { 2496 2497 Node* ctrl = lock->in(TypeFunc::Control); 2498 Node* mem = lock->in(TypeFunc::Memory); 2499 Node* obj = lock->obj_node(); 2500 Node* box = lock->box_node(); 2501 Node* flock = lock->fastlock_node(); 2502 2503 assert(!box->as_BoxLock()->is_eliminated(), "sanity"); 2504 2505 // Make the merge point 2506 Node *region; 2507 Node *mem_phi; 2508 Node *slow_path; 2509 2510 region = new RegionNode(3); 2511 // create a Phi for the memory state 2512 mem_phi = new PhiNode( region, Type::MEMORY, TypeRawPtr::BOTTOM); 2513 2514 // Optimize test; set region slot 2 2515 slow_path = opt_bits_test(ctrl, region, 2, flock, 0, 0); 2516 mem_phi->init_req(2, mem); 2517 2518 // Make slow path call 2519 CallNode* call = make_slow_call(lock, OptoRuntime::complete_monitor_enter_Type(), 2520 OptoRuntime::complete_monitor_locking_Java(), nullptr, slow_path, 2521 obj, box, nullptr); 2522 2523 _callprojs = call->extract_projections(false /*separate_io_proj*/, false /*do_asserts*/); 2524 2525 // Slow path can only throw asynchronous exceptions, which are always 2526 // de-opted. So the compiler thinks the slow-call can never throw an 2527 // exception. If it DOES throw an exception we would need the debug 2528 // info removed first (since if it throws there is no monitor). 2529 assert(_callprojs->fallthrough_ioproj == nullptr && _callprojs->catchall_ioproj == nullptr && 2530 _callprojs->catchall_memproj == nullptr && _callprojs->catchall_catchproj == nullptr, "Unexpected projection from Lock"); 2531 2532 // Capture slow path 2533 // disconnect fall-through projection from call and create a new one 2534 // hook up users of fall-through projection to region 2535 Node *slow_ctrl = _callprojs->fallthrough_proj->clone(); 2536 transform_later(slow_ctrl); 2537 _igvn.hash_delete(_callprojs->fallthrough_proj); 2538 _callprojs->fallthrough_proj->disconnect_inputs(C); 2539 region->init_req(1, slow_ctrl); 2540 // region inputs are now complete 2541 transform_later(region); 2542 _igvn.replace_node(_callprojs->fallthrough_proj, region); 2543 2544 Node *memproj = transform_later(new ProjNode(call, TypeFunc::Memory)); 2545 2546 mem_phi->init_req(1, memproj); 2547 2548 transform_later(mem_phi); 2549 2550 _igvn.replace_node(_callprojs->fallthrough_memproj, mem_phi); 2551 } 2552 2553 //------------------------------expand_unlock_node---------------------- 2554 void PhaseMacroExpand::expand_unlock_node(UnlockNode *unlock) { 2555 2556 Node* ctrl = unlock->in(TypeFunc::Control); 2557 Node* mem = unlock->in(TypeFunc::Memory); 2558 Node* obj = unlock->obj_node(); 2559 Node* box = unlock->box_node(); 2560 2561 assert(!box->as_BoxLock()->is_eliminated(), "sanity"); 2562 2563 // No need for a null check on unlock 2564 2565 // Make the merge point 2566 Node *region; 2567 Node *mem_phi; 2568 2569 region = new RegionNode(3); 2570 // create a Phi for the memory state 2571 mem_phi = new PhiNode( region, Type::MEMORY, TypeRawPtr::BOTTOM); 2572 2573 FastUnlockNode *funlock = new FastUnlockNode( ctrl, obj, box ); 2574 funlock = transform_later( funlock )->as_FastUnlock(); 2575 // Optimize test; set region slot 2 2576 Node *slow_path = opt_bits_test(ctrl, region, 2, funlock, 0, 0); 2577 Node *thread = transform_later(new ThreadLocalNode()); 2578 2579 CallNode *call = make_slow_call((CallNode *) unlock, OptoRuntime::complete_monitor_exit_Type(), 2580 CAST_FROM_FN_PTR(address, SharedRuntime::complete_monitor_unlocking_C), 2581 "complete_monitor_unlocking_C", slow_path, obj, box, thread); 2582 2583 _callprojs = call->extract_projections(false /*separate_io_proj*/, false /*do_asserts*/); 2584 assert(_callprojs->fallthrough_ioproj == nullptr && _callprojs->catchall_ioproj == nullptr && 2585 _callprojs->catchall_memproj == nullptr && _callprojs->catchall_catchproj == nullptr, "Unexpected projection from Lock"); 2586 2587 // No exceptions for unlocking 2588 // Capture slow path 2589 // disconnect fall-through projection from call and create a new one 2590 // hook up users of fall-through projection to region 2591 Node *slow_ctrl = _callprojs->fallthrough_proj->clone(); 2592 transform_later(slow_ctrl); 2593 _igvn.hash_delete(_callprojs->fallthrough_proj); 2594 _callprojs->fallthrough_proj->disconnect_inputs(C); 2595 region->init_req(1, slow_ctrl); 2596 // region inputs are now complete 2597 transform_later(region); 2598 _igvn.replace_node(_callprojs->fallthrough_proj, region); 2599 2600 Node *memproj = transform_later(new ProjNode(call, TypeFunc::Memory) ); 2601 mem_phi->init_req(1, memproj ); 2602 mem_phi->init_req(2, mem); 2603 transform_later(mem_phi); 2604 2605 _igvn.replace_node(_callprojs->fallthrough_memproj, mem_phi); 2606 } 2607 2608 // An inline type might be returned from the call but we don't know its 2609 // type. Either we get a buffered inline type (and nothing needs to be done) 2610 // or one of the values being returned is the klass of the inline type 2611 // and we need to allocate an inline type instance of that type and 2612 // initialize it with other values being returned. In that case, we 2613 // first try a fast path allocation and initialize the value with the 2614 // inline klass's pack handler or we fall back to a runtime call. 2615 void PhaseMacroExpand::expand_mh_intrinsic_return(CallStaticJavaNode* call) { 2616 assert(call->method()->is_method_handle_intrinsic(), "must be a method handle intrinsic call"); 2617 Node* ret = call->proj_out_or_null(TypeFunc::Parms); 2618 if (ret == nullptr) { 2619 return; 2620 } 2621 const TypeFunc* tf = call->_tf; 2622 const TypeTuple* domain = OptoRuntime::store_inline_type_fields_Type()->domain_cc(); 2623 const TypeFunc* new_tf = TypeFunc::make(tf->domain_sig(), tf->domain_cc(), tf->range_sig(), domain); 2624 call->_tf = new_tf; 2625 // Make sure the change of type is applied before projections are processed by igvn 2626 _igvn.set_type(call, call->Value(&_igvn)); 2627 _igvn.set_type(ret, ret->Value(&_igvn)); 2628 2629 // Before any new projection is added: 2630 CallProjections* projs = call->extract_projections(true, true); 2631 2632 // Create temporary hook nodes that will be replaced below. 2633 // Add an input to prevent hook nodes from being dead. 2634 Node* ctl = new Node(call); 2635 Node* mem = new Node(ctl); 2636 Node* io = new Node(ctl); 2637 Node* ex_ctl = new Node(ctl); 2638 Node* ex_mem = new Node(ctl); 2639 Node* ex_io = new Node(ctl); 2640 Node* res = new Node(ctl); 2641 2642 // Allocate a new buffered inline type only if a new one is not returned 2643 Node* cast = transform_later(new CastP2XNode(ctl, res)); 2644 Node* mask = MakeConX(0x1); 2645 Node* masked = transform_later(new AndXNode(cast, mask)); 2646 Node* cmp = transform_later(new CmpXNode(masked, mask)); 2647 Node* bol = transform_later(new BoolNode(cmp, BoolTest::eq)); 2648 IfNode* allocation_iff = new IfNode(ctl, bol, PROB_MAX, COUNT_UNKNOWN); 2649 transform_later(allocation_iff); 2650 Node* allocation_ctl = transform_later(new IfTrueNode(allocation_iff)); 2651 Node* no_allocation_ctl = transform_later(new IfFalseNode(allocation_iff)); 2652 Node* no_allocation_res = transform_later(new CheckCastPPNode(no_allocation_ctl, res, TypeInstPtr::BOTTOM)); 2653 2654 // Try to allocate a new buffered inline instance either from TLAB or eden space 2655 Node* needgc_ctrl = nullptr; // needgc means slowcase, i.e. allocation failed 2656 CallLeafNoFPNode* handler_call; 2657 const bool alloc_in_place = UseTLAB; 2658 if (alloc_in_place) { 2659 Node* fast_oop_ctrl = nullptr; 2660 Node* fast_oop_rawmem = nullptr; 2661 Node* mask2 = MakeConX(-2); 2662 Node* masked2 = transform_later(new AndXNode(cast, mask2)); 2663 Node* rawklassptr = transform_later(new CastX2PNode(masked2)); 2664 Node* klass_node = transform_later(new CheckCastPPNode(allocation_ctl, rawklassptr, TypeInstKlassPtr::OBJECT_OR_NULL)); 2665 Node* layout_val = make_load(nullptr, mem, klass_node, in_bytes(Klass::layout_helper_offset()), TypeInt::INT, T_INT); 2666 Node* size_in_bytes = ConvI2X(layout_val); 2667 BarrierSetC2* bs = BarrierSet::barrier_set()->barrier_set_c2(); 2668 Node* fast_oop = bs->obj_allocate(this, mem, allocation_ctl, size_in_bytes, io, needgc_ctrl, 2669 fast_oop_ctrl, fast_oop_rawmem, 2670 AllocateInstancePrefetchLines); 2671 // Allocation succeed, initialize buffered inline instance header firstly, 2672 // and then initialize its fields with an inline class specific handler 2673 Node* mark_node = makecon(TypeRawPtr::make((address)markWord::inline_type_prototype().value())); 2674 fast_oop_rawmem = make_store(fast_oop_ctrl, fast_oop_rawmem, fast_oop, oopDesc::mark_offset_in_bytes(), mark_node, T_ADDRESS); 2675 fast_oop_rawmem = make_store(fast_oop_ctrl, fast_oop_rawmem, fast_oop, oopDesc::klass_offset_in_bytes(), klass_node, T_METADATA); 2676 if (UseCompressedClassPointers) { 2677 fast_oop_rawmem = make_store(fast_oop_ctrl, fast_oop_rawmem, fast_oop, oopDesc::klass_gap_offset_in_bytes(), intcon(0), T_INT); 2678 } 2679 Node* fixed_block = make_load(fast_oop_ctrl, fast_oop_rawmem, klass_node, in_bytes(InstanceKlass::adr_inlineklass_fixed_block_offset()), TypeRawPtr::BOTTOM, T_ADDRESS); 2680 Node* pack_handler = make_load(fast_oop_ctrl, fast_oop_rawmem, fixed_block, in_bytes(InlineKlass::pack_handler_offset()), TypeRawPtr::BOTTOM, T_ADDRESS); 2681 handler_call = new CallLeafNoFPNode(OptoRuntime::pack_inline_type_Type(), 2682 nullptr, 2683 "pack handler", 2684 TypeRawPtr::BOTTOM); 2685 handler_call->init_req(TypeFunc::Control, fast_oop_ctrl); 2686 handler_call->init_req(TypeFunc::Memory, fast_oop_rawmem); 2687 handler_call->init_req(TypeFunc::I_O, top()); 2688 handler_call->init_req(TypeFunc::FramePtr, call->in(TypeFunc::FramePtr)); 2689 handler_call->init_req(TypeFunc::ReturnAdr, top()); 2690 handler_call->init_req(TypeFunc::Parms, pack_handler); 2691 handler_call->init_req(TypeFunc::Parms+1, fast_oop); 2692 } else { 2693 needgc_ctrl = allocation_ctl; 2694 } 2695 2696 // Allocation failed, fall back to a runtime call 2697 CallStaticJavaNode* slow_call = new CallStaticJavaNode(OptoRuntime::store_inline_type_fields_Type(), 2698 StubRoutines::store_inline_type_fields_to_buf(), 2699 "store_inline_type_fields", 2700 TypePtr::BOTTOM); 2701 slow_call->init_req(TypeFunc::Control, needgc_ctrl); 2702 slow_call->init_req(TypeFunc::Memory, mem); 2703 slow_call->init_req(TypeFunc::I_O, io); 2704 slow_call->init_req(TypeFunc::FramePtr, call->in(TypeFunc::FramePtr)); 2705 slow_call->init_req(TypeFunc::ReturnAdr, call->in(TypeFunc::ReturnAdr)); 2706 slow_call->init_req(TypeFunc::Parms, res); 2707 2708 Node* slow_ctl = transform_later(new ProjNode(slow_call, TypeFunc::Control)); 2709 Node* slow_mem = transform_later(new ProjNode(slow_call, TypeFunc::Memory)); 2710 Node* slow_io = transform_later(new ProjNode(slow_call, TypeFunc::I_O)); 2711 Node* slow_res = transform_later(new ProjNode(slow_call, TypeFunc::Parms)); 2712 Node* slow_catc = transform_later(new CatchNode(slow_ctl, slow_io, 2)); 2713 Node* slow_norm = transform_later(new CatchProjNode(slow_catc, CatchProjNode::fall_through_index, CatchProjNode::no_handler_bci)); 2714 Node* slow_excp = transform_later(new CatchProjNode(slow_catc, CatchProjNode::catch_all_index, CatchProjNode::no_handler_bci)); 2715 2716 Node* ex_r = new RegionNode(3); 2717 Node* ex_mem_phi = new PhiNode(ex_r, Type::MEMORY, TypePtr::BOTTOM); 2718 Node* ex_io_phi = new PhiNode(ex_r, Type::ABIO); 2719 ex_r->init_req(1, slow_excp); 2720 ex_mem_phi->init_req(1, slow_mem); 2721 ex_io_phi->init_req(1, slow_io); 2722 ex_r->init_req(2, ex_ctl); 2723 ex_mem_phi->init_req(2, ex_mem); 2724 ex_io_phi->init_req(2, ex_io); 2725 transform_later(ex_r); 2726 transform_later(ex_mem_phi); 2727 transform_later(ex_io_phi); 2728 2729 // We don't know how many values are returned. This assumes the 2730 // worst case, that all available registers are used. 2731 for (uint i = TypeFunc::Parms+1; i < domain->cnt(); i++) { 2732 if (domain->field_at(i) == Type::HALF) { 2733 slow_call->init_req(i, top()); 2734 if (alloc_in_place) { 2735 handler_call->init_req(i+1, top()); 2736 } 2737 continue; 2738 } 2739 Node* proj = transform_later(new ProjNode(call, i)); 2740 slow_call->init_req(i, proj); 2741 if (alloc_in_place) { 2742 handler_call->init_req(i+1, proj); 2743 } 2744 } 2745 // We can safepoint at that new call 2746 slow_call->copy_call_debug_info(&_igvn, call); 2747 transform_later(slow_call); 2748 if (alloc_in_place) { 2749 transform_later(handler_call); 2750 } 2751 2752 Node* fast_ctl = nullptr; 2753 Node* fast_res = nullptr; 2754 MergeMemNode* fast_mem = nullptr; 2755 if (alloc_in_place) { 2756 fast_ctl = transform_later(new ProjNode(handler_call, TypeFunc::Control)); 2757 Node* rawmem = transform_later(new ProjNode(handler_call, TypeFunc::Memory)); 2758 fast_res = transform_later(new ProjNode(handler_call, TypeFunc::Parms)); 2759 fast_mem = MergeMemNode::make(mem); 2760 fast_mem->set_memory_at(Compile::AliasIdxRaw, rawmem); 2761 transform_later(fast_mem); 2762 } 2763 2764 Node* r = new RegionNode(alloc_in_place ? 4 : 3); 2765 Node* mem_phi = new PhiNode(r, Type::MEMORY, TypePtr::BOTTOM); 2766 Node* io_phi = new PhiNode(r, Type::ABIO); 2767 Node* res_phi = new PhiNode(r, TypeInstPtr::BOTTOM); 2768 r->init_req(1, no_allocation_ctl); 2769 mem_phi->init_req(1, mem); 2770 io_phi->init_req(1, io); 2771 res_phi->init_req(1, no_allocation_res); 2772 r->init_req(2, slow_norm); 2773 mem_phi->init_req(2, slow_mem); 2774 io_phi->init_req(2, slow_io); 2775 res_phi->init_req(2, slow_res); 2776 if (alloc_in_place) { 2777 r->init_req(3, fast_ctl); 2778 mem_phi->init_req(3, fast_mem); 2779 io_phi->init_req(3, io); 2780 res_phi->init_req(3, fast_res); 2781 } 2782 transform_later(r); 2783 transform_later(mem_phi); 2784 transform_later(io_phi); 2785 transform_later(res_phi); 2786 2787 // Do not let stores that initialize this buffer be reordered with a subsequent 2788 // store that would make this buffer accessible by other threads. 2789 MemBarNode* mb = MemBarNode::make(C, Op_MemBarStoreStore, Compile::AliasIdxBot); 2790 transform_later(mb); 2791 mb->init_req(TypeFunc::Memory, mem_phi); 2792 mb->init_req(TypeFunc::Control, r); 2793 r = new ProjNode(mb, TypeFunc::Control); 2794 transform_later(r); 2795 mem_phi = new ProjNode(mb, TypeFunc::Memory); 2796 transform_later(mem_phi); 2797 2798 assert(projs->nb_resproj == 1, "unexpected number of results"); 2799 _igvn.replace_in_uses(projs->fallthrough_catchproj, r); 2800 _igvn.replace_in_uses(projs->fallthrough_memproj, mem_phi); 2801 _igvn.replace_in_uses(projs->fallthrough_ioproj, io_phi); 2802 _igvn.replace_in_uses(projs->resproj[0], res_phi); 2803 _igvn.replace_in_uses(projs->catchall_catchproj, ex_r); 2804 _igvn.replace_in_uses(projs->catchall_memproj, ex_mem_phi); 2805 _igvn.replace_in_uses(projs->catchall_ioproj, ex_io_phi); 2806 // The CatchNode should not use the ex_io_phi. Re-connect it to the catchall_ioproj. 2807 Node* cn = projs->fallthrough_catchproj->in(0); 2808 _igvn.replace_input_of(cn, 1, projs->catchall_ioproj); 2809 2810 _igvn.replace_node(ctl, projs->fallthrough_catchproj); 2811 _igvn.replace_node(mem, projs->fallthrough_memproj); 2812 _igvn.replace_node(io, projs->fallthrough_ioproj); 2813 _igvn.replace_node(res, projs->resproj[0]); 2814 _igvn.replace_node(ex_ctl, projs->catchall_catchproj); 2815 _igvn.replace_node(ex_mem, projs->catchall_memproj); 2816 _igvn.replace_node(ex_io, projs->catchall_ioproj); 2817 } 2818 2819 void PhaseMacroExpand::expand_subtypecheck_node(SubTypeCheckNode *check) { 2820 assert(check->in(SubTypeCheckNode::Control) == nullptr, "should be pinned"); 2821 Node* bol = check->unique_out(); 2822 Node* obj_or_subklass = check->in(SubTypeCheckNode::ObjOrSubKlass); 2823 Node* superklass = check->in(SubTypeCheckNode::SuperKlass); 2824 assert(bol->is_Bool() && bol->as_Bool()->_test._test == BoolTest::ne, "unexpected bool node"); 2825 2826 for (DUIterator_Last imin, i = bol->last_outs(imin); i >= imin; --i) { 2827 Node* iff = bol->last_out(i); 2828 assert(iff->is_If(), "where's the if?"); 2829 2830 if (iff->in(0)->is_top()) { 2831 _igvn.replace_input_of(iff, 1, C->top()); 2832 continue; 2833 } 2834 2835 Node* iftrue = iff->as_If()->proj_out(1); 2836 Node* iffalse = iff->as_If()->proj_out(0); 2837 Node* ctrl = iff->in(0); 2838 2839 Node* subklass = nullptr; 2840 if (_igvn.type(obj_or_subklass)->isa_klassptr()) { 2841 subklass = obj_or_subklass; 2842 } else { 2843 Node* k_adr = basic_plus_adr(obj_or_subklass, oopDesc::klass_offset_in_bytes()); 2844 subklass = _igvn.transform(LoadKlassNode::make(_igvn, C->immutable_memory(), k_adr, TypeInstPtr::KLASS, TypeInstKlassPtr::OBJECT)); 2845 } 2846 2847 Node* not_subtype_ctrl = Phase::gen_subtype_check(subklass, superklass, &ctrl, nullptr, _igvn, check->method(), check->bci()); 2848 2849 _igvn.replace_input_of(iff, 0, C->top()); 2850 _igvn.replace_node(iftrue, not_subtype_ctrl); 2851 _igvn.replace_node(iffalse, ctrl); 2852 } 2853 _igvn.replace_node(check, C->top()); 2854 } 2855 2856 // FlatArrayCheckNode (array1 array2 ...) is expanded into: 2857 // 2858 // long mark = array1.mark | array2.mark | ...; 2859 // long locked_bit = markWord::unlocked_value & array1.mark & array2.mark & ...; 2860 // if (locked_bit == 0) { 2861 // // One array is locked, load prototype header from the klass 2862 // mark = array1.klass.proto | array2.klass.proto | ... 2863 // } 2864 // if ((mark & markWord::flat_array_bit_in_place) == 0) { 2865 // ... 2866 // } 2867 void PhaseMacroExpand::expand_flatarraycheck_node(FlatArrayCheckNode* check) { 2868 bool array_inputs = _igvn.type(check->in(FlatArrayCheckNode::ArrayOrKlass))->isa_oopptr() != nullptr; 2869 if (array_inputs) { 2870 Node* mark = MakeConX(0); 2871 Node* locked_bit = MakeConX(markWord::unlocked_value); 2872 Node* mem = check->in(FlatArrayCheckNode::Memory); 2873 for (uint i = FlatArrayCheckNode::ArrayOrKlass; i < check->req(); ++i) { 2874 Node* ary = check->in(i); 2875 const TypeOopPtr* t = _igvn.type(ary)->isa_oopptr(); 2876 assert(t != nullptr, "Mixing array and klass inputs"); 2877 assert(!t->is_flat() && !t->is_not_flat(), "Should have been optimized out"); 2878 Node* mark_adr = basic_plus_adr(ary, oopDesc::mark_offset_in_bytes()); 2879 Node* mark_load = _igvn.transform(LoadNode::make(_igvn, nullptr, mem, mark_adr, mark_adr->bottom_type()->is_ptr(), TypeX_X, TypeX_X->basic_type(), MemNode::unordered)); 2880 mark = _igvn.transform(new OrXNode(mark, mark_load)); 2881 locked_bit = _igvn.transform(new AndXNode(locked_bit, mark_load)); 2882 } 2883 assert(!mark->is_Con(), "Should have been optimized out"); 2884 Node* cmp = _igvn.transform(new CmpXNode(locked_bit, MakeConX(0))); 2885 Node* is_unlocked = _igvn.transform(new BoolNode(cmp, BoolTest::ne)); 2886 2887 // BoolNode might be shared, replace each if user 2888 Node* old_bol = check->unique_out(); 2889 assert(old_bol->is_Bool() && old_bol->as_Bool()->_test._test == BoolTest::ne, "unexpected condition"); 2890 for (DUIterator_Last imin, i = old_bol->last_outs(imin); i >= imin; --i) { 2891 IfNode* old_iff = old_bol->last_out(i)->as_If(); 2892 Node* ctrl = old_iff->in(0); 2893 RegionNode* region = new RegionNode(3); 2894 Node* mark_phi = new PhiNode(region, TypeX_X); 2895 2896 // Check if array is unlocked 2897 IfNode* iff = _igvn.transform(new IfNode(ctrl, is_unlocked, PROB_MAX, COUNT_UNKNOWN))->as_If(); 2898 2899 // Unlocked: Use bits from mark word 2900 region->init_req(1, _igvn.transform(new IfTrueNode(iff))); 2901 mark_phi->init_req(1, mark); 2902 2903 // Locked: Load prototype header from klass 2904 ctrl = _igvn.transform(new IfFalseNode(iff)); 2905 Node* proto = MakeConX(0); 2906 for (uint i = FlatArrayCheckNode::ArrayOrKlass; i < check->req(); ++i) { 2907 Node* ary = check->in(i); 2908 // Make loads control dependent to make sure they are only executed if array is locked 2909 Node* klass_adr = basic_plus_adr(ary, oopDesc::klass_offset_in_bytes()); 2910 Node* klass = _igvn.transform(LoadKlassNode::make(_igvn, C->immutable_memory(), klass_adr, TypeInstPtr::KLASS, TypeInstKlassPtr::OBJECT)); 2911 Node* proto_adr = basic_plus_adr(klass, in_bytes(Klass::prototype_header_offset())); 2912 Node* proto_load = _igvn.transform(LoadNode::make(_igvn, ctrl, C->immutable_memory(), proto_adr, proto_adr->bottom_type()->is_ptr(), TypeX_X, TypeX_X->basic_type(), MemNode::unordered)); 2913 proto = _igvn.transform(new OrXNode(proto, proto_load)); 2914 } 2915 region->init_req(2, ctrl); 2916 mark_phi->init_req(2, proto); 2917 2918 // Check if flat array bits are set 2919 Node* mask = MakeConX(markWord::flat_array_bit_in_place); 2920 Node* masked = _igvn.transform(new AndXNode(_igvn.transform(mark_phi), mask)); 2921 cmp = _igvn.transform(new CmpXNode(masked, MakeConX(0))); 2922 Node* is_not_flat = _igvn.transform(new BoolNode(cmp, BoolTest::eq)); 2923 2924 ctrl = _igvn.transform(region); 2925 iff = _igvn.transform(new IfNode(ctrl, is_not_flat, PROB_MAX, COUNT_UNKNOWN))->as_If(); 2926 _igvn.replace_node(old_iff, iff); 2927 } 2928 _igvn.replace_node(check, C->top()); 2929 } else { 2930 // Fall back to layout helper check 2931 Node* lhs = intcon(0); 2932 for (uint i = FlatArrayCheckNode::ArrayOrKlass; i < check->req(); ++i) { 2933 Node* array_or_klass = check->in(i); 2934 Node* klass = nullptr; 2935 const TypePtr* t = _igvn.type(array_or_klass)->is_ptr(); 2936 assert(!t->is_flat() && !t->is_not_flat(), "Should have been optimized out"); 2937 if (t->isa_oopptr() != nullptr) { 2938 Node* klass_adr = basic_plus_adr(array_or_klass, oopDesc::klass_offset_in_bytes()); 2939 klass = transform_later(LoadKlassNode::make(_igvn, C->immutable_memory(), klass_adr, TypeInstPtr::KLASS, TypeInstKlassPtr::OBJECT)); 2940 } else { 2941 assert(t->isa_klassptr(), "Unexpected input type"); 2942 klass = array_or_klass; 2943 } 2944 Node* lh_addr = basic_plus_adr(klass, in_bytes(Klass::layout_helper_offset())); 2945 Node* lh_val = _igvn.transform(LoadNode::make(_igvn, nullptr, C->immutable_memory(), lh_addr, lh_addr->bottom_type()->is_ptr(), TypeInt::INT, T_INT, MemNode::unordered)); 2946 lhs = _igvn.transform(new OrINode(lhs, lh_val)); 2947 } 2948 Node* masked = transform_later(new AndINode(lhs, intcon(Klass::_lh_array_tag_flat_value_bit_inplace))); 2949 Node* cmp = transform_later(new CmpINode(masked, intcon(0))); 2950 Node* bol = transform_later(new BoolNode(cmp, BoolTest::eq)); 2951 Node* m2b = transform_later(new Conv2BNode(masked)); 2952 // The matcher expects the input to If nodes to be produced by a Bool(CmpI..) 2953 // pattern, but the input to other potential users (e.g. Phi) to be some 2954 // other pattern (e.g. a Conv2B node, possibly idealized as a CMoveI). 2955 Node* old_bol = check->unique_out(); 2956 for (DUIterator_Last imin, i = old_bol->last_outs(imin); i >= imin; --i) { 2957 Node* user = old_bol->last_out(i); 2958 for (uint j = 0; j < user->req(); j++) { 2959 Node* n = user->in(j); 2960 if (n == old_bol) { 2961 _igvn.replace_input_of(user, j, user->is_If() ? bol : m2b); 2962 } 2963 } 2964 } 2965 _igvn.replace_node(check, C->top()); 2966 } 2967 } 2968 2969 // Perform refining of strip mined loop nodes in the macro nodes list. 2970 void PhaseMacroExpand::refine_strip_mined_loop_macro_nodes() { 2971 for (int i = C->macro_count(); i > 0; i--) { 2972 Node* n = C->macro_node(i - 1); 2973 if (n->is_OuterStripMinedLoop()) { 2974 n->as_OuterStripMinedLoop()->adjust_strip_mined_loop(&_igvn); 2975 } 2976 } 2977 } 2978 2979 //---------------------------eliminate_macro_nodes---------------------- 2980 // Eliminate scalar replaced allocations and associated locks. 2981 void PhaseMacroExpand::eliminate_macro_nodes(bool eliminate_locks) { 2982 if (C->macro_count() == 0) { 2983 return; 2984 } 2985 2986 if (StressMacroElimination) { 2987 C->shuffle_macro_nodes(); 2988 } 2989 NOT_PRODUCT(int membar_before = count_MemBar(C);) 2990 2991 int iteration = 0; 2992 while (C->macro_count() > 0) { 2993 if (iteration++ > 100) { 2994 assert(false, "Too slow convergence of macro elimination"); 2995 break; 2996 } 2997 2998 // Postpone lock elimination to after EA when most allocations are eliminated 2999 // because they might block lock elimination if their escape state isn't 3000 // determined yet and we only got one chance at eliminating the lock. 3001 if (eliminate_locks) { 3002 // Before elimination may re-mark (change to Nested or NonEscObj) 3003 // all associated (same box and obj) lock and unlock nodes. 3004 int cnt = C->macro_count(); 3005 for (int i=0; i < cnt; i++) { 3006 Node *n = C->macro_node(i); 3007 if (n->is_AbstractLock()) { // Lock and Unlock nodes 3008 mark_eliminated_locking_nodes(n->as_AbstractLock()); 3009 } 3010 } 3011 // Re-marking may break consistency of Coarsened locks. 3012 if (!C->coarsened_locks_consistent()) { 3013 return; // recompile without Coarsened locks if broken 3014 } else { 3015 // After coarsened locks are eliminated locking regions 3016 // become unbalanced. We should not execute any more 3017 // locks elimination optimizations on them. 3018 C->mark_unbalanced_boxes(); 3019 } 3020 } 3021 3022 bool progress = false; 3023 for (int i = C->macro_count(); i > 0; i = MIN2(i - 1, C->macro_count())) { // more than 1 element can be eliminated at once 3024 Node* n = C->macro_node(i - 1); 3025 bool success = false; 3026 DEBUG_ONLY(int old_macro_count = C->macro_count();) 3027 switch (n->class_id()) { 3028 case Node::Class_Allocate: 3029 case Node::Class_AllocateArray: 3030 success = eliminate_allocate_node(n->as_Allocate()); 3031 #ifndef PRODUCT 3032 if (success && PrintOptoStatistics) { 3033 Atomic::inc(&PhaseMacroExpand::_objs_scalar_replaced_counter); 3034 } 3035 #endif 3036 break; 3037 case Node::Class_CallStaticJava: { 3038 CallStaticJavaNode* call = n->as_CallStaticJava(); 3039 if (!call->method()->is_method_handle_intrinsic()) { 3040 success = eliminate_boxing_node(n->as_CallStaticJava()); 3041 } 3042 break; 3043 } 3044 case Node::Class_Lock: 3045 case Node::Class_Unlock: 3046 if (eliminate_locks) { 3047 success = eliminate_locking_node(n->as_AbstractLock()); 3048 #ifndef PRODUCT 3049 if (success && PrintOptoStatistics) { 3050 Atomic::inc(&PhaseMacroExpand::_monitor_objects_removed_counter); 3051 } 3052 #endif 3053 } 3054 break; 3055 case Node::Class_ArrayCopy: 3056 break; 3057 case Node::Class_OuterStripMinedLoop: 3058 break; 3059 case Node::Class_SubTypeCheck: 3060 break; 3061 case Node::Class_Opaque1: 3062 break; 3063 case Node::Class_FlatArrayCheck: 3064 break; 3065 default: 3066 assert(n->Opcode() == Op_LoopLimit || 3067 n->Opcode() == Op_ModD || 3068 n->Opcode() == Op_ModF || 3069 n->is_OpaqueNotNull() || 3070 n->is_OpaqueInitializedAssertionPredicate() || 3071 n->Opcode() == Op_MaxL || 3072 n->Opcode() == Op_MinL || 3073 BarrierSet::barrier_set()->barrier_set_c2()->is_gc_barrier_node(n), 3074 "unknown node type in macro list"); 3075 } 3076 assert(success == (C->macro_count() < old_macro_count), "elimination reduces macro count"); 3077 progress = progress || success; 3078 if (success) { 3079 C->print_method(PHASE_AFTER_MACRO_ELIMINATION_STEP, 5, n); 3080 } 3081 } 3082 3083 // Ensure the graph after PhaseMacroExpand::eliminate_macro_nodes is canonical (no igvn 3084 // transformation is pending). If an allocation is used only in safepoints, elimination of 3085 // other macro nodes can remove all these safepoints, allowing the allocation to be removed. 3086 // Hence after igvn we retry removing macro nodes if some progress that has been made in this 3087 // iteration. 3088 _igvn.set_delay_transform(false); 3089 _igvn.optimize(); 3090 if (C->failing()) { 3091 return; 3092 } 3093 _igvn.set_delay_transform(true); 3094 3095 if (!progress) { 3096 break; 3097 } 3098 } 3099 #ifndef PRODUCT 3100 if (PrintOptoStatistics) { 3101 int membar_after = count_MemBar(C); 3102 Atomic::add(&PhaseMacroExpand::_memory_barriers_removed_counter, membar_before - membar_after); 3103 } 3104 #endif 3105 } 3106 3107 void PhaseMacroExpand::eliminate_opaque_looplimit_macro_nodes() { 3108 if (C->macro_count() == 0) { 3109 return; 3110 } 3111 refine_strip_mined_loop_macro_nodes(); 3112 // Eliminate Opaque and LoopLimit nodes. Do it after all loop optimizations. 3113 bool progress = true; 3114 while (progress) { 3115 progress = false; 3116 for (int i = C->macro_count(); i > 0; i--) { 3117 Node* n = C->macro_node(i-1); 3118 bool success = false; 3119 DEBUG_ONLY(int old_macro_count = C->macro_count();) 3120 if (n->Opcode() == Op_LoopLimit) { 3121 // Remove it from macro list and put on IGVN worklist to optimize. 3122 C->remove_macro_node(n); 3123 _igvn._worklist.push(n); 3124 success = true; 3125 } else if (n->Opcode() == Op_CallStaticJava) { 3126 CallStaticJavaNode* call = n->as_CallStaticJava(); 3127 if (!call->method()->is_method_handle_intrinsic()) { 3128 // Remove it from macro list and put on IGVN worklist to optimize. 3129 C->remove_macro_node(n); 3130 _igvn._worklist.push(n); 3131 success = true; 3132 } 3133 } else if (n->is_Opaque1()) { 3134 _igvn.replace_node(n, n->in(1)); 3135 success = true; 3136 } else if (n->is_OpaqueNotNull()) { 3137 // Tests with OpaqueNotNull nodes are implicitly known to be true. Replace the node with true. In debug builds, 3138 // we leave the test in the graph to have an additional sanity check at runtime. If the test fails (i.e. a bug), 3139 // we will execute a Halt node. 3140 #ifdef ASSERT 3141 _igvn.replace_node(n, n->in(1)); 3142 #else 3143 _igvn.replace_node(n, _igvn.intcon(1)); 3144 #endif 3145 success = true; 3146 } else if (n->is_OpaqueInitializedAssertionPredicate()) { 3147 // Initialized Assertion Predicates must always evaluate to true. Therefore, we get rid of them in product 3148 // builds as they are useless. In debug builds we keep them as additional verification code. Even though 3149 // loop opts are already over, we want to keep Initialized Assertion Predicates alive as long as possible to 3150 // enable folding of dead control paths within which cast nodes become top after due to impossible types - 3151 // even after loop opts are over. Therefore, we delay the removal of these opaque nodes until now. 3152 #ifdef ASSERT 3153 _igvn.replace_node(n, n->in(1)); 3154 #else 3155 _igvn.replace_node(n, _igvn.intcon(1)); 3156 #endif // ASSERT 3157 } else if (n->Opcode() == Op_OuterStripMinedLoop) { 3158 C->remove_macro_node(n); 3159 success = true; 3160 } else if (n->Opcode() == Op_MaxL) { 3161 // Since MaxL and MinL are not implemented in the backend, we expand them to 3162 // a CMoveL construct now. At least until here, the type could be computed 3163 // precisely. CMoveL is not so smart, but we can give it at least the best 3164 // type we know abouot n now. 3165 Node* repl = MaxNode::signed_max(n->in(1), n->in(2), _igvn.type(n), _igvn); 3166 _igvn.replace_node(n, repl); 3167 success = true; 3168 } else if (n->Opcode() == Op_MinL) { 3169 Node* repl = MaxNode::signed_min(n->in(1), n->in(2), _igvn.type(n), _igvn); 3170 _igvn.replace_node(n, repl); 3171 success = true; 3172 } 3173 assert(!success || (C->macro_count() == (old_macro_count - 1)), "elimination must have deleted one node from macro list"); 3174 progress = progress || success; 3175 if (success) { 3176 C->print_method(PHASE_AFTER_MACRO_ELIMINATION_STEP, 5, n); 3177 } 3178 } 3179 } 3180 } 3181 3182 //------------------------------expand_macro_nodes---------------------- 3183 // Returns true if a failure occurred. 3184 bool PhaseMacroExpand::expand_macro_nodes() { 3185 if (StressMacroExpansion) { 3186 C->shuffle_macro_nodes(); 3187 } 3188 3189 // Clean up the graph so we're less likely to hit the maximum node 3190 // limit 3191 _igvn.set_delay_transform(false); 3192 _igvn.optimize(); 3193 if (C->failing()) return true; 3194 _igvn.set_delay_transform(true); 3195 3196 3197 // Because we run IGVN after each expansion, some macro nodes may go 3198 // dead and be removed from the list as we iterate over it. Move 3199 // Allocate nodes (processed in a second pass) at the beginning of 3200 // the list and then iterate from the last element of the list until 3201 // an Allocate node is seen. This is robust to random deletion in 3202 // the list due to nodes going dead. 3203 C->sort_macro_nodes(); 3204 3205 // expand arraycopy "macro" nodes first 3206 // For ReduceBulkZeroing, we must first process all arraycopy nodes 3207 // before the allocate nodes are expanded. 3208 while (C->macro_count() > 0) { 3209 int macro_count = C->macro_count(); 3210 Node * n = C->macro_node(macro_count-1); 3211 assert(n->is_macro(), "only macro nodes expected here"); 3212 if (_igvn.type(n) == Type::TOP || (n->in(0) != nullptr && n->in(0)->is_top())) { 3213 // node is unreachable, so don't try to expand it 3214 C->remove_macro_node(n); 3215 continue; 3216 } 3217 if (n->is_Allocate()) { 3218 break; 3219 } 3220 // Make sure expansion will not cause node limit to be exceeded. 3221 // Worst case is a macro node gets expanded into about 200 nodes. 3222 // Allow 50% more for optimization. 3223 if (C->check_node_count(300, "out of nodes before macro expansion")) { 3224 return true; 3225 } 3226 3227 DEBUG_ONLY(int old_macro_count = C->macro_count();) 3228 switch (n->class_id()) { 3229 case Node::Class_Lock: 3230 expand_lock_node(n->as_Lock()); 3231 break; 3232 case Node::Class_Unlock: 3233 expand_unlock_node(n->as_Unlock()); 3234 break; 3235 case Node::Class_ArrayCopy: 3236 expand_arraycopy_node(n->as_ArrayCopy()); 3237 break; 3238 case Node::Class_SubTypeCheck: 3239 expand_subtypecheck_node(n->as_SubTypeCheck()); 3240 break; 3241 case Node::Class_CallStaticJava: 3242 expand_mh_intrinsic_return(n->as_CallStaticJava()); 3243 C->remove_macro_node(n); 3244 break; 3245 case Node::Class_FlatArrayCheck: 3246 expand_flatarraycheck_node(n->as_FlatArrayCheck()); 3247 break; 3248 default: 3249 switch (n->Opcode()) { 3250 case Op_ModD: 3251 case Op_ModF: { 3252 bool is_drem = n->Opcode() == Op_ModD; 3253 CallNode* mod_macro = n->as_Call(); 3254 CallNode* call = new CallLeafNode(mod_macro->tf(), 3255 is_drem ? CAST_FROM_FN_PTR(address, SharedRuntime::drem) 3256 : CAST_FROM_FN_PTR(address, SharedRuntime::frem), 3257 is_drem ? "drem" : "frem", TypeRawPtr::BOTTOM); 3258 call->init_req(TypeFunc::Control, mod_macro->in(TypeFunc::Control)); 3259 call->init_req(TypeFunc::I_O, mod_macro->in(TypeFunc::I_O)); 3260 call->init_req(TypeFunc::Memory, mod_macro->in(TypeFunc::Memory)); 3261 call->init_req(TypeFunc::ReturnAdr, mod_macro->in(TypeFunc::ReturnAdr)); 3262 call->init_req(TypeFunc::FramePtr, mod_macro->in(TypeFunc::FramePtr)); 3263 for (unsigned int i = 0; i < mod_macro->tf()->domain_cc()->cnt() - TypeFunc::Parms; i++) { 3264 call->init_req(TypeFunc::Parms + i, mod_macro->in(TypeFunc::Parms + i)); 3265 } 3266 _igvn.replace_node(mod_macro, call); 3267 transform_later(call); 3268 break; 3269 } 3270 default: 3271 assert(false, "unknown node type in macro list"); 3272 } 3273 } 3274 assert(C->macro_count() == (old_macro_count - 1), "expansion must have deleted one node from macro list"); 3275 if (C->failing()) return true; 3276 C->print_method(PHASE_AFTER_MACRO_EXPANSION_STEP, 5, n); 3277 3278 // Clean up the graph so we're less likely to hit the maximum node 3279 // limit 3280 _igvn.set_delay_transform(false); 3281 _igvn.optimize(); 3282 if (C->failing()) return true; 3283 _igvn.set_delay_transform(true); 3284 } 3285 3286 // All nodes except Allocate nodes are expanded now. There could be 3287 // new optimization opportunities (such as folding newly created 3288 // load from a just allocated object). Run IGVN. 3289 3290 // expand "macro" nodes 3291 // nodes are removed from the macro list as they are processed 3292 while (C->macro_count() > 0) { 3293 int macro_count = C->macro_count(); 3294 Node * n = C->macro_node(macro_count-1); 3295 assert(n->is_macro(), "only macro nodes expected here"); 3296 if (_igvn.type(n) == Type::TOP || (n->in(0) != nullptr && n->in(0)->is_top())) { 3297 // node is unreachable, so don't try to expand it 3298 C->remove_macro_node(n); 3299 continue; 3300 } 3301 // Make sure expansion will not cause node limit to be exceeded. 3302 // Worst case is a macro node gets expanded into about 200 nodes. 3303 // Allow 50% more for optimization. 3304 if (C->check_node_count(300, "out of nodes before macro expansion")) { 3305 return true; 3306 } 3307 switch (n->class_id()) { 3308 case Node::Class_Allocate: 3309 expand_allocate(n->as_Allocate()); 3310 break; 3311 case Node::Class_AllocateArray: 3312 expand_allocate_array(n->as_AllocateArray()); 3313 break; 3314 default: 3315 assert(false, "unknown node type in macro list"); 3316 } 3317 assert(C->macro_count() < macro_count, "must have deleted a node from macro list"); 3318 if (C->failing()) return true; 3319 C->print_method(PHASE_AFTER_MACRO_EXPANSION_STEP, 5, n); 3320 3321 // Clean up the graph so we're less likely to hit the maximum node 3322 // limit 3323 _igvn.set_delay_transform(false); 3324 _igvn.optimize(); 3325 if (C->failing()) return true; 3326 _igvn.set_delay_transform(true); 3327 } 3328 3329 _igvn.set_delay_transform(false); 3330 return false; 3331 } 3332 3333 #ifndef PRODUCT 3334 int PhaseMacroExpand::_objs_scalar_replaced_counter = 0; 3335 int PhaseMacroExpand::_monitor_objects_removed_counter = 0; 3336 int PhaseMacroExpand::_GC_barriers_removed_counter = 0; 3337 int PhaseMacroExpand::_memory_barriers_removed_counter = 0; 3338 3339 void PhaseMacroExpand::print_statistics() { 3340 tty->print("Objects scalar replaced = %d, ", Atomic::load(&_objs_scalar_replaced_counter)); 3341 tty->print("Monitor objects removed = %d, ", Atomic::load(&_monitor_objects_removed_counter)); 3342 tty->print("GC barriers removed = %d, ", Atomic::load(&_GC_barriers_removed_counter)); 3343 tty->print_cr("Memory barriers removed = %d", Atomic::load(&_memory_barriers_removed_counter)); 3344 } 3345 3346 int PhaseMacroExpand::count_MemBar(Compile *C) { 3347 if (!PrintOptoStatistics) { 3348 return 0; 3349 } 3350 Unique_Node_List ideal_nodes; 3351 int total = 0; 3352 ideal_nodes.map(C->live_nodes(), nullptr); 3353 ideal_nodes.push(C->root()); 3354 for (uint next = 0; next < ideal_nodes.size(); ++next) { 3355 Node* n = ideal_nodes.at(next); 3356 if (n->is_MemBar()) { 3357 total++; 3358 } 3359 for (DUIterator_Fast imax, i = n->fast_outs(imax); i < imax; i++) { 3360 Node* m = n->fast_out(i); 3361 ideal_nodes.push(m); 3362 } 3363 } 3364 return total; 3365 } 3366 #endif