1 /* 2 * Copyright (c) 2005, 2017, Oracle and/or its affiliates. All rights reserved. 3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. 4 * 5 * This code is free software; you can redistribute it and/or modify it 6 * under the terms of the GNU General Public License version 2 only, as 7 * published by the Free Software Foundation. 8 * 9 * This code is distributed in the hope that it will be useful, but WITHOUT 10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 12 * version 2 for more details (a copy is included in the LICENSE file that 13 * accompanied this code). 14 * 15 * You should have received a copy of the GNU General Public License version 16 * 2 along with this work; if not, write to the Free Software Foundation, 17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. 18 * 19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA 20 * or visit www.oracle.com if you need additional information or have any 21 * questions. 22 * 23 */ 24 25 #include "precompiled.hpp" 26 #include "compiler/compileLog.hpp" 27 #include "libadt/vectset.hpp" 28 #include "opto/addnode.hpp" 29 #include "opto/arraycopynode.hpp" 30 #include "opto/callnode.hpp" 31 #include "opto/castnode.hpp" 32 #include "opto/cfgnode.hpp" 33 #include "opto/compile.hpp" 34 #include "opto/convertnode.hpp" 35 #include "opto/graphKit.hpp" 36 #include "opto/locknode.hpp" 37 #include "opto/loopnode.hpp" 38 #include "opto/macro.hpp" 39 #include "opto/memnode.hpp" 40 #include "opto/narrowptrnode.hpp" 41 #include "opto/node.hpp" 42 #include "opto/opaquenode.hpp" 43 #include "opto/phaseX.hpp" 44 #include "opto/rootnode.hpp" 45 #include "opto/runtime.hpp" 46 #include "opto/subnode.hpp" 47 #include "opto/type.hpp" 48 #include "runtime/sharedRuntime.hpp" 49 50 51 // 52 // Replace any references to "oldref" in inputs to "use" with "newref". 53 // Returns the number of replacements made. 54 // 55 int PhaseMacroExpand::replace_input(Node *use, Node *oldref, Node *newref) { 56 int nreplacements = 0; 57 uint req = use->req(); 58 for (uint j = 0; j < use->len(); j++) { 59 Node *uin = use->in(j); 60 if (uin == oldref) { 61 if (j < req) 62 use->set_req(j, newref); 63 else 64 use->set_prec(j, newref); 65 nreplacements++; 66 } else if (j >= req && uin == NULL) { 67 break; 68 } 69 } 70 return nreplacements; 71 } 72 73 void PhaseMacroExpand::copy_call_debug_info(CallNode *oldcall, CallNode * newcall) { 74 // Copy debug information and adjust JVMState information 75 uint old_dbg_start = oldcall->tf()->domain()->cnt(); 76 uint new_dbg_start = newcall->tf()->domain()->cnt(); 77 int jvms_adj = new_dbg_start - old_dbg_start; 78 assert (new_dbg_start == newcall->req(), "argument count mismatch"); 79 80 // SafePointScalarObject node could be referenced several times in debug info. 81 // Use Dict to record cloned nodes. 82 Dict* sosn_map = new Dict(cmpkey,hashkey); 83 for (uint i = old_dbg_start; i < oldcall->req(); i++) { 84 Node* old_in = oldcall->in(i); 85 // Clone old SafePointScalarObjectNodes, adjusting their field contents. 86 if (old_in != NULL && old_in->is_SafePointScalarObject()) { 87 SafePointScalarObjectNode* old_sosn = old_in->as_SafePointScalarObject(); 88 uint old_unique = C->unique(); 89 Node* new_in = old_sosn->clone(sosn_map); 90 if (old_unique != C->unique()) { // New node? 91 new_in->set_req(0, C->root()); // reset control edge 92 new_in = transform_later(new_in); // Register new node. 93 } 94 old_in = new_in; 95 } 96 newcall->add_req(old_in); 97 } 98 99 // JVMS may be shared so clone it before we modify it 100 newcall->set_jvms(oldcall->jvms() != NULL ? oldcall->jvms()->clone_deep(C) : NULL); 101 for (JVMState *jvms = newcall->jvms(); jvms != NULL; jvms = jvms->caller()) { 102 jvms->set_map(newcall); 103 jvms->set_locoff(jvms->locoff()+jvms_adj); 104 jvms->set_stkoff(jvms->stkoff()+jvms_adj); 105 jvms->set_monoff(jvms->monoff()+jvms_adj); 106 jvms->set_scloff(jvms->scloff()+jvms_adj); 107 jvms->set_endoff(jvms->endoff()+jvms_adj); 108 } 109 } 110 111 Node* PhaseMacroExpand::opt_bits_test(Node* ctrl, Node* region, int edge, Node* word, int mask, int bits, bool return_fast_path) { 112 Node* cmp; 113 if (mask != 0) { 114 Node* and_node = transform_later(new AndXNode(word, MakeConX(mask))); 115 cmp = transform_later(new CmpXNode(and_node, MakeConX(bits))); 116 } else { 117 cmp = word; 118 } 119 Node* bol = transform_later(new BoolNode(cmp, BoolTest::ne)); 120 IfNode* iff = new IfNode( ctrl, bol, PROB_MIN, COUNT_UNKNOWN ); 121 transform_later(iff); 122 123 // Fast path taken. 124 Node *fast_taken = transform_later(new IfFalseNode(iff)); 125 126 // Fast path not-taken, i.e. slow path 127 Node *slow_taken = transform_later(new IfTrueNode(iff)); 128 129 if (return_fast_path) { 130 region->init_req(edge, slow_taken); // Capture slow-control 131 return fast_taken; 132 } else { 133 region->init_req(edge, fast_taken); // Capture fast-control 134 return slow_taken; 135 } 136 } 137 138 //--------------------copy_predefined_input_for_runtime_call-------------------- 139 void PhaseMacroExpand::copy_predefined_input_for_runtime_call(Node * ctrl, CallNode* oldcall, CallNode* call) { 140 // Set fixed predefined input arguments 141 call->init_req( TypeFunc::Control, ctrl ); 142 call->init_req( TypeFunc::I_O , oldcall->in( TypeFunc::I_O) ); 143 call->init_req( TypeFunc::Memory , oldcall->in( TypeFunc::Memory ) ); // ????? 144 call->init_req( TypeFunc::ReturnAdr, oldcall->in( TypeFunc::ReturnAdr ) ); 145 call->init_req( TypeFunc::FramePtr, oldcall->in( TypeFunc::FramePtr ) ); 146 } 147 148 //------------------------------make_slow_call--------------------------------- 149 CallNode* PhaseMacroExpand::make_slow_call(CallNode *oldcall, const TypeFunc* slow_call_type, 150 address slow_call, const char* leaf_name, Node* slow_path, 151 Node* parm0, Node* parm1, Node* parm2) { 152 153 // Slow-path call 154 CallNode *call = leaf_name 155 ? (CallNode*)new CallLeafNode ( slow_call_type, slow_call, leaf_name, TypeRawPtr::BOTTOM ) 156 : (CallNode*)new CallStaticJavaNode( slow_call_type, slow_call, OptoRuntime::stub_name(slow_call), oldcall->jvms()->bci(), TypeRawPtr::BOTTOM ); 157 158 // Slow path call has no side-effects, uses few values 159 copy_predefined_input_for_runtime_call(slow_path, oldcall, call ); 160 if (parm0 != NULL) call->init_req(TypeFunc::Parms+0, parm0); 161 if (parm1 != NULL) call->init_req(TypeFunc::Parms+1, parm1); 162 if (parm2 != NULL) call->init_req(TypeFunc::Parms+2, parm2); 163 copy_call_debug_info(oldcall, call); 164 call->set_cnt(PROB_UNLIKELY_MAG(4)); // Same effect as RC_UNCOMMON. 165 _igvn.replace_node(oldcall, call); 166 transform_later(call); 167 168 return call; 169 } 170 171 void PhaseMacroExpand::extract_call_projections(CallNode *call) { 172 _fallthroughproj = NULL; 173 _fallthroughcatchproj = NULL; 174 _ioproj_fallthrough = NULL; 175 _ioproj_catchall = NULL; 176 _catchallcatchproj = NULL; 177 _memproj_fallthrough = NULL; 178 _memproj_catchall = NULL; 179 _resproj = NULL; 180 for (DUIterator_Fast imax, i = call->fast_outs(imax); i < imax; i++) { 181 ProjNode *pn = call->fast_out(i)->as_Proj(); 182 switch (pn->_con) { 183 case TypeFunc::Control: 184 { 185 // For Control (fallthrough) and I_O (catch_all_index) we have CatchProj -> Catch -> Proj 186 _fallthroughproj = pn; 187 DUIterator_Fast jmax, j = pn->fast_outs(jmax); 188 const Node *cn = pn->fast_out(j); 189 if (cn->is_Catch()) { 190 ProjNode *cpn = NULL; 191 for (DUIterator_Fast kmax, k = cn->fast_outs(kmax); k < kmax; k++) { 192 cpn = cn->fast_out(k)->as_Proj(); 193 assert(cpn->is_CatchProj(), "must be a CatchProjNode"); 194 if (cpn->_con == CatchProjNode::fall_through_index) 195 _fallthroughcatchproj = cpn; 196 else { 197 assert(cpn->_con == CatchProjNode::catch_all_index, "must be correct index."); 198 _catchallcatchproj = cpn; 199 } 200 } 201 } 202 break; 203 } 204 case TypeFunc::I_O: 205 if (pn->_is_io_use) 206 _ioproj_catchall = pn; 207 else 208 _ioproj_fallthrough = pn; 209 break; 210 case TypeFunc::Memory: 211 if (pn->_is_io_use) 212 _memproj_catchall = pn; 213 else 214 _memproj_fallthrough = pn; 215 break; 216 case TypeFunc::Parms: 217 _resproj = pn; 218 break; 219 default: 220 assert(false, "unexpected projection from allocation node."); 221 } 222 } 223 224 } 225 226 // Eliminate a card mark sequence. p2x is a ConvP2XNode 227 void PhaseMacroExpand::eliminate_card_mark(Node* p2x) { 228 assert(p2x->Opcode() == Op_CastP2X, "ConvP2XNode required"); 229 if (!UseG1GC) { 230 // vanilla/CMS post barrier 231 Node *shift = p2x->unique_out(); 232 Node *addp = shift->unique_out(); 233 for (DUIterator_Last jmin, j = addp->last_outs(jmin); j >= jmin; --j) { 234 Node *mem = addp->last_out(j); 235 if (UseCondCardMark && mem->is_Load()) { 236 assert(mem->Opcode() == Op_LoadB, "unexpected code shape"); 237 // The load is checking if the card has been written so 238 // replace it with zero to fold the test. 239 _igvn.replace_node(mem, intcon(0)); 240 continue; 241 } 242 assert(mem->is_Store(), "store required"); 243 _igvn.replace_node(mem, mem->in(MemNode::Memory)); 244 } 245 } else { 246 // G1 pre/post barriers 247 assert(p2x->outcnt() <= 2, "expects 1 or 2 users: Xor and URShift nodes"); 248 // It could be only one user, URShift node, in Object.clone() intrinsic 249 // but the new allocation is passed to arraycopy stub and it could not 250 // be scalar replaced. So we don't check the case. 251 252 // An other case of only one user (Xor) is when the value check for NULL 253 // in G1 post barrier is folded after CCP so the code which used URShift 254 // is removed. 255 256 // Take Region node before eliminating post barrier since it also 257 // eliminates CastP2X node when it has only one user. 258 Node* this_region = p2x->in(0); 259 assert(this_region != NULL, ""); 260 261 // Remove G1 post barrier. 262 263 // Search for CastP2X->Xor->URShift->Cmp path which 264 // checks if the store done to a different from the value's region. 265 // And replace Cmp with #0 (false) to collapse G1 post barrier. 266 Node* xorx = p2x->find_out_with(Op_XorX); 267 if (xorx != NULL) { 268 Node* shift = xorx->unique_out(); 269 Node* cmpx = shift->unique_out(); 270 assert(cmpx->is_Cmp() && cmpx->unique_out()->is_Bool() && 271 cmpx->unique_out()->as_Bool()->_test._test == BoolTest::ne, 272 "missing region check in G1 post barrier"); 273 _igvn.replace_node(cmpx, makecon(TypeInt::CC_EQ)); 274 275 // Remove G1 pre barrier. 276 277 // Search "if (marking != 0)" check and set it to "false". 278 // There is no G1 pre barrier if previous stored value is NULL 279 // (for example, after initialization). 280 if (this_region->is_Region() && this_region->req() == 3) { 281 int ind = 1; 282 if (!this_region->in(ind)->is_IfFalse()) { 283 ind = 2; 284 } 285 if (this_region->in(ind)->is_IfFalse() && 286 this_region->in(ind)->in(0)->Opcode() == Op_If) { 287 Node* bol = this_region->in(ind)->in(0)->in(1); 288 assert(bol->is_Bool(), ""); 289 cmpx = bol->in(1); 290 if (bol->as_Bool()->_test._test == BoolTest::ne && 291 cmpx->is_Cmp() && cmpx->in(2) == intcon(0) && 292 cmpx->in(1)->is_Load()) { 293 Node* adr = cmpx->in(1)->as_Load()->in(MemNode::Address); 294 const int marking_offset = in_bytes(JavaThread::satb_mark_queue_offset() + 295 SATBMarkQueue::byte_offset_of_active()); 296 if (adr->is_AddP() && adr->in(AddPNode::Base) == top() && 297 adr->in(AddPNode::Address)->Opcode() == Op_ThreadLocal && 298 adr->in(AddPNode::Offset) == MakeConX(marking_offset)) { 299 _igvn.replace_node(cmpx, makecon(TypeInt::CC_EQ)); 300 } 301 } 302 } 303 } 304 } else { 305 assert(!GraphKit::use_ReduceInitialCardMarks(), "can only happen with card marking"); 306 // This is a G1 post barrier emitted by the Object.clone() intrinsic. 307 // Search for the CastP2X->URShiftX->AddP->LoadB->Cmp path which checks if the card 308 // is marked as young_gen and replace the Cmp with 0 (false) to collapse the barrier. 309 Node* shift = p2x->find_out_with(Op_URShiftX); 310 assert(shift != NULL, "missing G1 post barrier"); 311 Node* addp = shift->unique_out(); 312 Node* load = addp->find_out_with(Op_LoadB); 313 assert(load != NULL, "missing G1 post barrier"); 314 Node* cmpx = load->unique_out(); 315 assert(cmpx->is_Cmp() && cmpx->unique_out()->is_Bool() && 316 cmpx->unique_out()->as_Bool()->_test._test == BoolTest::ne, 317 "missing card value check in G1 post barrier"); 318 _igvn.replace_node(cmpx, makecon(TypeInt::CC_EQ)); 319 // There is no G1 pre barrier in this case 320 } 321 // Now CastP2X can be removed since it is used only on dead path 322 // which currently still alive until igvn optimize it. 323 assert(p2x->outcnt() == 0 || p2x->unique_out()->Opcode() == Op_URShiftX, ""); 324 _igvn.replace_node(p2x, top()); 325 } 326 } 327 328 // Search for a memory operation for the specified memory slice. 329 static Node *scan_mem_chain(Node *mem, int alias_idx, int offset, Node *start_mem, Node *alloc, PhaseGVN *phase) { 330 Node *orig_mem = mem; 331 Node *alloc_mem = alloc->in(TypeFunc::Memory); 332 const TypeOopPtr *tinst = phase->C->get_adr_type(alias_idx)->isa_oopptr(); 333 while (true) { 334 if (mem == alloc_mem || mem == start_mem ) { 335 return mem; // hit one of our sentinels 336 } else if (mem->is_MergeMem()) { 337 mem = mem->as_MergeMem()->memory_at(alias_idx); 338 } else if (mem->is_Proj() && mem->as_Proj()->_con == TypeFunc::Memory) { 339 Node *in = mem->in(0); 340 // we can safely skip over safepoints, calls, locks and membars because we 341 // already know that the object is safe to eliminate. 342 if (in->is_Initialize() && in->as_Initialize()->allocation() == alloc) { 343 return in; 344 } else if (in->is_Call()) { 345 CallNode *call = in->as_Call(); 346 if (call->may_modify(tinst, phase)) { 347 assert(call->is_ArrayCopy(), "ArrayCopy is the only call node that doesn't make allocation escape"); 348 if (call->as_ArrayCopy()->modifies(offset, offset, phase, false)) { 349 return in; 350 } 351 } 352 mem = in->in(TypeFunc::Memory); 353 } else if (in->is_MemBar()) { 354 ArrayCopyNode* ac = NULL; 355 if (ArrayCopyNode::may_modify(tinst, in->as_MemBar(), phase, ac)) { 356 assert(ac != NULL && ac->is_clonebasic(), "Only basic clone is a non escaping clone"); 357 return ac; 358 } 359 mem = in->in(TypeFunc::Memory); 360 } else { 361 assert(false, "unexpected projection"); 362 } 363 } else if (mem->is_Store()) { 364 const TypePtr* atype = mem->as_Store()->adr_type(); 365 int adr_idx = phase->C->get_alias_index(atype); 366 if (adr_idx == alias_idx) { 367 assert(atype->isa_oopptr(), "address type must be oopptr"); 368 int adr_offset = atype->offset(); 369 uint adr_iid = atype->is_oopptr()->instance_id(); 370 // Array elements references have the same alias_idx 371 // but different offset and different instance_id. 372 if (adr_offset == offset && adr_iid == alloc->_idx) 373 return mem; 374 } else { 375 assert(adr_idx == Compile::AliasIdxRaw, "address must match or be raw"); 376 } 377 mem = mem->in(MemNode::Memory); 378 } else if (mem->is_ClearArray()) { 379 if (!ClearArrayNode::step_through(&mem, alloc->_idx, phase)) { 380 // Can not bypass initialization of the instance 381 // we are looking. 382 debug_only(intptr_t offset;) 383 assert(alloc == AllocateNode::Ideal_allocation(mem->in(3), phase, offset), "sanity"); 384 InitializeNode* init = alloc->as_Allocate()->initialization(); 385 // We are looking for stored value, return Initialize node 386 // or memory edge from Allocate node. 387 if (init != NULL) 388 return init; 389 else 390 return alloc->in(TypeFunc::Memory); // It will produce zero value (see callers). 391 } 392 // Otherwise skip it (the call updated 'mem' value). 393 } else if (mem->Opcode() == Op_SCMemProj) { 394 mem = mem->in(0); 395 Node* adr = NULL; 396 if (mem->is_LoadStore()) { 397 adr = mem->in(MemNode::Address); 398 } else { 399 assert(mem->Opcode() == Op_EncodeISOArray || 400 mem->Opcode() == Op_StrCompressedCopy, "sanity"); 401 adr = mem->in(3); // Destination array 402 } 403 const TypePtr* atype = adr->bottom_type()->is_ptr(); 404 int adr_idx = phase->C->get_alias_index(atype); 405 if (adr_idx == alias_idx) { 406 DEBUG_ONLY(mem->dump();) 407 assert(false, "Object is not scalar replaceable if a LoadStore node accesses its field"); 408 return NULL; 409 } 410 mem = mem->in(MemNode::Memory); 411 } else if (mem->Opcode() == Op_StrInflatedCopy) { 412 Node* adr = mem->in(3); // Destination array 413 const TypePtr* atype = adr->bottom_type()->is_ptr(); 414 int adr_idx = phase->C->get_alias_index(atype); 415 if (adr_idx == alias_idx) { 416 DEBUG_ONLY(mem->dump();) 417 assert(false, "Object is not scalar replaceable if a StrInflatedCopy node accesses its field"); 418 return NULL; 419 } 420 mem = mem->in(MemNode::Memory); 421 } else { 422 return mem; 423 } 424 assert(mem != orig_mem, "dead memory loop"); 425 } 426 } 427 428 // Generate loads from source of the arraycopy for fields of 429 // destination needed at a deoptimization point 430 Node* PhaseMacroExpand::make_arraycopy_load(ArrayCopyNode* ac, intptr_t offset, Node* ctl, Node* mem, BasicType ft, const Type *ftype, AllocateNode *alloc) { 431 BasicType bt = ft; 432 const Type *type = ftype; 433 if (ft == T_NARROWOOP) { 434 bt = T_OBJECT; 435 type = ftype->make_oopptr(); 436 } 437 Node* res = NULL; 438 if (ac->is_clonebasic()) { 439 Node* base = ac->in(ArrayCopyNode::Src)->in(AddPNode::Base); 440 Node* adr = _igvn.transform(new AddPNode(base, base, MakeConX(offset))); 441 const TypePtr* adr_type = _igvn.type(base)->is_ptr()->add_offset(offset); 442 res = LoadNode::make(_igvn, ctl, mem, adr, adr_type, type, bt, MemNode::unordered, LoadNode::Pinned); 443 } else { 444 if (ac->modifies(offset, offset, &_igvn, true)) { 445 assert(ac->in(ArrayCopyNode::Dest) == alloc->result_cast(), "arraycopy destination should be allocation's result"); 446 uint shift = exact_log2(type2aelembytes(bt)); 447 Node* diff = _igvn.transform(new SubINode(ac->in(ArrayCopyNode::SrcPos), ac->in(ArrayCopyNode::DestPos))); 448 #ifdef _LP64 449 diff = _igvn.transform(new ConvI2LNode(diff)); 450 #endif 451 diff = _igvn.transform(new LShiftXNode(diff, intcon(shift))); 452 453 Node* off = _igvn.transform(new AddXNode(MakeConX(offset), diff)); 454 Node* base = ac->in(ArrayCopyNode::Src); 455 Node* adr = _igvn.transform(new AddPNode(base, base, off)); 456 const TypePtr* adr_type = _igvn.type(base)->is_ptr()->add_offset(offset); 457 res = LoadNode::make(_igvn, ctl, mem, adr, adr_type, type, bt, MemNode::unordered, LoadNode::Pinned); 458 } 459 } 460 if (res != NULL) { 461 res = _igvn.transform(res); 462 if (ftype->isa_narrowoop()) { 463 // PhaseMacroExpand::scalar_replacement adds DecodeN nodes 464 res = _igvn.transform(new EncodePNode(res, ftype)); 465 } 466 return res; 467 } 468 return NULL; 469 } 470 471 // 472 // Given a Memory Phi, compute a value Phi containing the values from stores 473 // on the input paths. 474 // Note: this function is recursive, its depth is limited by the "level" argument 475 // Returns the computed Phi, or NULL if it cannot compute it. 476 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) { 477 assert(mem->is_Phi(), "sanity"); 478 int alias_idx = C->get_alias_index(adr_t); 479 int offset = adr_t->offset(); 480 int instance_id = adr_t->instance_id(); 481 482 // Check if an appropriate value phi already exists. 483 Node* region = mem->in(0); 484 for (DUIterator_Fast kmax, k = region->fast_outs(kmax); k < kmax; k++) { 485 Node* phi = region->fast_out(k); 486 if (phi->is_Phi() && phi != mem && 487 phi->as_Phi()->is_same_inst_field(phi_type, (int)mem->_idx, instance_id, alias_idx, offset)) { 488 return phi; 489 } 490 } 491 // Check if an appropriate new value phi already exists. 492 Node* new_phi = value_phis->find(mem->_idx); 493 if (new_phi != NULL) 494 return new_phi; 495 496 if (level <= 0) { 497 return NULL; // Give up: phi tree too deep 498 } 499 Node *start_mem = C->start()->proj_out(TypeFunc::Memory); 500 Node *alloc_mem = alloc->in(TypeFunc::Memory); 501 502 uint length = mem->req(); 503 GrowableArray <Node *> values(length, length, NULL, false); 504 505 // create a new Phi for the value 506 PhiNode *phi = new PhiNode(mem->in(0), phi_type, NULL, mem->_idx, instance_id, alias_idx, offset); 507 transform_later(phi); 508 value_phis->push(phi, mem->_idx); 509 510 for (uint j = 1; j < length; j++) { 511 Node *in = mem->in(j); 512 if (in == NULL || in->is_top()) { 513 values.at_put(j, in); 514 } else { 515 Node *val = scan_mem_chain(in, alias_idx, offset, start_mem, alloc, &_igvn); 516 if (val == start_mem || val == alloc_mem) { 517 // hit a sentinel, return appropriate 0 value 518 values.at_put(j, _igvn.zerocon(ft)); 519 continue; 520 } 521 if (val->is_Initialize()) { 522 val = val->as_Initialize()->find_captured_store(offset, type2aelembytes(ft), &_igvn); 523 } 524 if (val == NULL) { 525 return NULL; // can't find a value on this path 526 } 527 if (val == mem) { 528 values.at_put(j, mem); 529 } else if (val->is_Store()) { 530 values.at_put(j, val->in(MemNode::ValueIn)); 531 } else if(val->is_Proj() && val->in(0) == alloc) { 532 values.at_put(j, _igvn.zerocon(ft)); 533 } else if (val->is_Phi()) { 534 val = value_from_mem_phi(val, ft, phi_type, adr_t, alloc, value_phis, level-1); 535 if (val == NULL) { 536 return NULL; 537 } 538 values.at_put(j, val); 539 } else if (val->Opcode() == Op_SCMemProj) { 540 assert(val->in(0)->is_LoadStore() || 541 val->in(0)->Opcode() == Op_EncodeISOArray || 542 val->in(0)->Opcode() == Op_StrCompressedCopy, "sanity"); 543 assert(false, "Object is not scalar replaceable if a LoadStore node accesses its field"); 544 return NULL; 545 } else if (val->is_ArrayCopy()) { 546 Node* res = make_arraycopy_load(val->as_ArrayCopy(), offset, val->in(0), val->in(TypeFunc::Memory), ft, phi_type, alloc); 547 if (res == NULL) { 548 return NULL; 549 } 550 values.at_put(j, res); 551 } else { 552 #ifdef ASSERT 553 val->dump(); 554 assert(false, "unknown node on this path"); 555 #endif 556 return NULL; // unknown node on this path 557 } 558 } 559 } 560 // Set Phi's inputs 561 for (uint j = 1; j < length; j++) { 562 if (values.at(j) == mem) { 563 phi->init_req(j, phi); 564 } else { 565 phi->init_req(j, values.at(j)); 566 } 567 } 568 return phi; 569 } 570 571 // Search the last value stored into the object's field. 572 Node *PhaseMacroExpand::value_from_mem(Node *sfpt_mem, Node *sfpt_ctl, BasicType ft, const Type *ftype, const TypeOopPtr *adr_t, AllocateNode *alloc) { 573 assert(adr_t->is_known_instance_field(), "instance required"); 574 int instance_id = adr_t->instance_id(); 575 assert((uint)instance_id == alloc->_idx, "wrong allocation"); 576 577 int alias_idx = C->get_alias_index(adr_t); 578 int offset = adr_t->offset(); 579 Node *start_mem = C->start()->proj_out(TypeFunc::Memory); 580 Node *alloc_ctrl = alloc->in(TypeFunc::Control); 581 Node *alloc_mem = alloc->in(TypeFunc::Memory); 582 Arena *a = Thread::current()->resource_area(); 583 VectorSet visited(a); 584 585 586 bool done = sfpt_mem == alloc_mem; 587 Node *mem = sfpt_mem; 588 while (!done) { 589 if (visited.test_set(mem->_idx)) { 590 return NULL; // found a loop, give up 591 } 592 mem = scan_mem_chain(mem, alias_idx, offset, start_mem, alloc, &_igvn); 593 if (mem == start_mem || mem == alloc_mem) { 594 done = true; // hit a sentinel, return appropriate 0 value 595 } else if (mem->is_Initialize()) { 596 mem = mem->as_Initialize()->find_captured_store(offset, type2aelembytes(ft), &_igvn); 597 if (mem == NULL) { 598 done = true; // Something go wrong. 599 } else if (mem->is_Store()) { 600 const TypePtr* atype = mem->as_Store()->adr_type(); 601 assert(C->get_alias_index(atype) == Compile::AliasIdxRaw, "store is correct memory slice"); 602 done = true; 603 } 604 } else if (mem->is_Store()) { 605 const TypeOopPtr* atype = mem->as_Store()->adr_type()->isa_oopptr(); 606 assert(atype != NULL, "address type must be oopptr"); 607 assert(C->get_alias_index(atype) == alias_idx && 608 atype->is_known_instance_field() && atype->offset() == offset && 609 atype->instance_id() == instance_id, "store is correct memory slice"); 610 done = true; 611 } else if (mem->is_Phi()) { 612 // try to find a phi's unique input 613 Node *unique_input = NULL; 614 Node *top = C->top(); 615 for (uint i = 1; i < mem->req(); i++) { 616 Node *n = scan_mem_chain(mem->in(i), alias_idx, offset, start_mem, alloc, &_igvn); 617 if (n == NULL || n == top || n == mem) { 618 continue; 619 } else if (unique_input == NULL) { 620 unique_input = n; 621 } else if (unique_input != n) { 622 unique_input = top; 623 break; 624 } 625 } 626 if (unique_input != NULL && unique_input != top) { 627 mem = unique_input; 628 } else { 629 done = true; 630 } 631 } else if (mem->is_ArrayCopy()) { 632 done = true; 633 } else { 634 assert(false, "unexpected node"); 635 } 636 } 637 if (mem != NULL) { 638 if (mem == start_mem || mem == alloc_mem) { 639 // hit a sentinel, return appropriate 0 value 640 return _igvn.zerocon(ft); 641 } else if (mem->is_Store()) { 642 return mem->in(MemNode::ValueIn); 643 } else if (mem->is_Phi()) { 644 // attempt to produce a Phi reflecting the values on the input paths of the Phi 645 Node_Stack value_phis(a, 8); 646 Node * phi = value_from_mem_phi(mem, ft, ftype, adr_t, alloc, &value_phis, ValueSearchLimit); 647 if (phi != NULL) { 648 return phi; 649 } else { 650 // Kill all new Phis 651 while(value_phis.is_nonempty()) { 652 Node* n = value_phis.node(); 653 _igvn.replace_node(n, C->top()); 654 value_phis.pop(); 655 } 656 } 657 } else if (mem->is_ArrayCopy()) { 658 Node* ctl = mem->in(0); 659 Node* m = mem->in(TypeFunc::Memory); 660 if (sfpt_ctl->is_Proj() && sfpt_ctl->as_Proj()->is_uncommon_trap_proj(Deoptimization::Reason_none)) { 661 // pin the loads in the uncommon trap path 662 ctl = sfpt_ctl; 663 m = sfpt_mem; 664 } 665 return make_arraycopy_load(mem->as_ArrayCopy(), offset, ctl, m, ft, ftype, alloc); 666 } 667 } 668 // Something go wrong. 669 return NULL; 670 } 671 672 // Check the possibility of scalar replacement. 673 bool PhaseMacroExpand::can_eliminate_allocation(AllocateNode *alloc, GrowableArray <SafePointNode *>& safepoints) { 674 // Scan the uses of the allocation to check for anything that would 675 // prevent us from eliminating it. 676 NOT_PRODUCT( const char* fail_eliminate = NULL; ) 677 DEBUG_ONLY( Node* disq_node = NULL; ) 678 bool can_eliminate = true; 679 680 Node* res = alloc->result_cast(); 681 const TypeOopPtr* res_type = NULL; 682 if (res == NULL) { 683 // All users were eliminated. 684 } else if (!res->is_CheckCastPP()) { 685 NOT_PRODUCT(fail_eliminate = "Allocation does not have unique CheckCastPP";) 686 can_eliminate = false; 687 } else { 688 res_type = _igvn.type(res)->isa_oopptr(); 689 if (res_type == NULL) { 690 NOT_PRODUCT(fail_eliminate = "Neither instance or array allocation";) 691 can_eliminate = false; 692 } else if (res_type->isa_aryptr()) { 693 int length = alloc->in(AllocateNode::ALength)->find_int_con(-1); 694 if (length < 0) { 695 NOT_PRODUCT(fail_eliminate = "Array's size is not constant";) 696 can_eliminate = false; 697 } 698 } 699 } 700 701 if (can_eliminate && res != NULL) { 702 for (DUIterator_Fast jmax, j = res->fast_outs(jmax); 703 j < jmax && can_eliminate; j++) { 704 Node* use = res->fast_out(j); 705 706 if (use->is_AddP()) { 707 const TypePtr* addp_type = _igvn.type(use)->is_ptr(); 708 int offset = addp_type->offset(); 709 710 if (offset == Type::OffsetTop || offset == Type::OffsetBot) { 711 NOT_PRODUCT(fail_eliminate = "Undefined field referrence";) 712 can_eliminate = false; 713 break; 714 } 715 for (DUIterator_Fast kmax, k = use->fast_outs(kmax); 716 k < kmax && can_eliminate; k++) { 717 Node* n = use->fast_out(k); 718 if (!n->is_Store() && n->Opcode() != Op_CastP2X && 719 !(n->is_ArrayCopy() && 720 n->as_ArrayCopy()->is_clonebasic() && 721 n->in(ArrayCopyNode::Dest) == use)) { 722 DEBUG_ONLY(disq_node = n;) 723 if (n->is_Load() || n->is_LoadStore()) { 724 NOT_PRODUCT(fail_eliminate = "Field load";) 725 } else { 726 NOT_PRODUCT(fail_eliminate = "Not store field referrence";) 727 } 728 can_eliminate = false; 729 } 730 } 731 } else if (use->is_ArrayCopy() && 732 (use->as_ArrayCopy()->is_arraycopy_validated() || 733 use->as_ArrayCopy()->is_copyof_validated() || 734 use->as_ArrayCopy()->is_copyofrange_validated()) && 735 use->in(ArrayCopyNode::Dest) == res) { 736 // ok to eliminate 737 } else if (use->is_SafePoint()) { 738 SafePointNode* sfpt = use->as_SafePoint(); 739 if (sfpt->is_Call() && sfpt->as_Call()->has_non_debug_use(res)) { 740 // Object is passed as argument. 741 DEBUG_ONLY(disq_node = use;) 742 NOT_PRODUCT(fail_eliminate = "Object is passed as argument";) 743 can_eliminate = false; 744 } 745 Node* sfptMem = sfpt->memory(); 746 if (sfptMem == NULL || sfptMem->is_top()) { 747 DEBUG_ONLY(disq_node = use;) 748 NOT_PRODUCT(fail_eliminate = "NULL or TOP memory";) 749 can_eliminate = false; 750 } else { 751 safepoints.append_if_missing(sfpt); 752 } 753 } else if (use->Opcode() != Op_CastP2X) { // CastP2X is used by card mark 754 if (use->is_Phi()) { 755 if (use->outcnt() == 1 && use->unique_out()->Opcode() == Op_Return) { 756 NOT_PRODUCT(fail_eliminate = "Object is return value";) 757 } else { 758 NOT_PRODUCT(fail_eliminate = "Object is referenced by Phi";) 759 } 760 DEBUG_ONLY(disq_node = use;) 761 } else { 762 if (use->Opcode() == Op_Return) { 763 NOT_PRODUCT(fail_eliminate = "Object is return value";) 764 }else { 765 NOT_PRODUCT(fail_eliminate = "Object is referenced by node";) 766 } 767 DEBUG_ONLY(disq_node = use;) 768 } 769 can_eliminate = false; 770 } 771 } 772 } 773 774 #ifndef PRODUCT 775 if (PrintEliminateAllocations) { 776 if (can_eliminate) { 777 tty->print("Scalar "); 778 if (res == NULL) 779 alloc->dump(); 780 else 781 res->dump(); 782 } else if (alloc->_is_scalar_replaceable) { 783 tty->print("NotScalar (%s)", fail_eliminate); 784 if (res == NULL) 785 alloc->dump(); 786 else 787 res->dump(); 788 #ifdef ASSERT 789 if (disq_node != NULL) { 790 tty->print(" >>>> "); 791 disq_node->dump(); 792 } 793 #endif /*ASSERT*/ 794 } 795 } 796 #endif 797 return can_eliminate; 798 } 799 800 // Do scalar replacement. 801 bool PhaseMacroExpand::scalar_replacement(AllocateNode *alloc, GrowableArray <SafePointNode *>& safepoints) { 802 GrowableArray <SafePointNode *> safepoints_done; 803 804 ciKlass* klass = NULL; 805 ciInstanceKlass* iklass = NULL; 806 int nfields = 0; 807 int array_base = 0; 808 int element_size = 0; 809 BasicType basic_elem_type = T_ILLEGAL; 810 ciType* elem_type = NULL; 811 812 Node* res = alloc->result_cast(); 813 assert(res == NULL || res->is_CheckCastPP(), "unexpected AllocateNode result"); 814 const TypeOopPtr* res_type = NULL; 815 if (res != NULL) { // Could be NULL when there are no users 816 res_type = _igvn.type(res)->isa_oopptr(); 817 } 818 819 if (res != NULL) { 820 klass = res_type->klass(); 821 if (res_type->isa_instptr()) { 822 // find the fields of the class which will be needed for safepoint debug information 823 assert(klass->is_instance_klass(), "must be an instance klass."); 824 iklass = klass->as_instance_klass(); 825 nfields = iklass->nof_nonstatic_fields(); 826 } else { 827 // find the array's elements which will be needed for safepoint debug information 828 nfields = alloc->in(AllocateNode::ALength)->find_int_con(-1); 829 assert(klass->is_array_klass() && nfields >= 0, "must be an array klass."); 830 elem_type = klass->as_array_klass()->element_type(); 831 basic_elem_type = elem_type->basic_type(); 832 array_base = arrayOopDesc::base_offset_in_bytes(basic_elem_type); 833 element_size = type2aelembytes(basic_elem_type); 834 } 835 } 836 // 837 // Process the safepoint uses 838 // 839 while (safepoints.length() > 0) { 840 SafePointNode* sfpt = safepoints.pop(); 841 Node* mem = sfpt->memory(); 842 Node* ctl = sfpt->control(); 843 assert(sfpt->jvms() != NULL, "missed JVMS"); 844 // Fields of scalar objs are referenced only at the end 845 // of regular debuginfo at the last (youngest) JVMS. 846 // Record relative start index. 847 uint first_ind = (sfpt->req() - sfpt->jvms()->scloff()); 848 SafePointScalarObjectNode* sobj = new SafePointScalarObjectNode(res_type, 849 #ifdef ASSERT 850 alloc, 851 #endif 852 first_ind, nfields); 853 sobj->init_req(0, C->root()); 854 transform_later(sobj); 855 856 // Scan object's fields adding an input to the safepoint for each field. 857 for (int j = 0; j < nfields; j++) { 858 intptr_t offset; 859 ciField* field = NULL; 860 if (iklass != NULL) { 861 field = iklass->nonstatic_field_at(j); 862 offset = field->offset(); 863 elem_type = field->type(); 864 basic_elem_type = field->layout_type(); 865 } else { 866 offset = array_base + j * (intptr_t)element_size; 867 } 868 869 const Type *field_type; 870 // The next code is taken from Parse::do_get_xxx(). 871 if (basic_elem_type == T_OBJECT || basic_elem_type == T_ARRAY) { 872 if (!elem_type->is_loaded()) { 873 field_type = TypeInstPtr::BOTTOM; 874 } else if (field != NULL && field->is_static_constant()) { 875 // This can happen if the constant oop is non-perm. 876 ciObject* con = field->constant_value().as_object(); 877 // Do not "join" in the previous type; it doesn't add value, 878 // and may yield a vacuous result if the field is of interface type. 879 field_type = TypeOopPtr::make_from_constant(con)->isa_oopptr(); 880 assert(field_type != NULL, "field singleton type must be consistent"); 881 } else { 882 field_type = TypeOopPtr::make_from_klass(elem_type->as_klass()); 883 } 884 if (UseCompressedOops) { 885 field_type = field_type->make_narrowoop(); 886 basic_elem_type = T_NARROWOOP; 887 } 888 } else { 889 field_type = Type::get_const_basic_type(basic_elem_type); 890 } 891 892 const TypeOopPtr *field_addr_type = res_type->add_offset(offset)->isa_oopptr(); 893 894 Node *field_val = value_from_mem(mem, ctl, basic_elem_type, field_type, field_addr_type, alloc); 895 if (field_val == NULL) { 896 // We weren't able to find a value for this field, 897 // give up on eliminating this allocation. 898 899 // Remove any extra entries we added to the safepoint. 900 uint last = sfpt->req() - 1; 901 for (int k = 0; k < j; k++) { 902 sfpt->del_req(last--); 903 } 904 _igvn._worklist.push(sfpt); 905 // rollback processed safepoints 906 while (safepoints_done.length() > 0) { 907 SafePointNode* sfpt_done = safepoints_done.pop(); 908 // remove any extra entries we added to the safepoint 909 last = sfpt_done->req() - 1; 910 for (int k = 0; k < nfields; k++) { 911 sfpt_done->del_req(last--); 912 } 913 JVMState *jvms = sfpt_done->jvms(); 914 jvms->set_endoff(sfpt_done->req()); 915 // Now make a pass over the debug information replacing any references 916 // to SafePointScalarObjectNode with the allocated object. 917 int start = jvms->debug_start(); 918 int end = jvms->debug_end(); 919 for (int i = start; i < end; i++) { 920 if (sfpt_done->in(i)->is_SafePointScalarObject()) { 921 SafePointScalarObjectNode* scobj = sfpt_done->in(i)->as_SafePointScalarObject(); 922 if (scobj->first_index(jvms) == sfpt_done->req() && 923 scobj->n_fields() == (uint)nfields) { 924 assert(scobj->alloc() == alloc, "sanity"); 925 sfpt_done->set_req(i, res); 926 } 927 } 928 } 929 _igvn._worklist.push(sfpt_done); 930 } 931 #ifndef PRODUCT 932 if (PrintEliminateAllocations) { 933 if (field != NULL) { 934 tty->print("=== At SafePoint node %d can't find value of Field: ", 935 sfpt->_idx); 936 field->print(); 937 int field_idx = C->get_alias_index(field_addr_type); 938 tty->print(" (alias_idx=%d)", field_idx); 939 } else { // Array's element 940 tty->print("=== At SafePoint node %d can't find value of array element [%d]", 941 sfpt->_idx, j); 942 } 943 tty->print(", which prevents elimination of: "); 944 if (res == NULL) 945 alloc->dump(); 946 else 947 res->dump(); 948 } 949 #endif 950 return false; 951 } 952 if (UseCompressedOops && field_type->isa_narrowoop()) { 953 // Enable "DecodeN(EncodeP(Allocate)) --> Allocate" transformation 954 // to be able scalar replace the allocation. 955 if (field_val->is_EncodeP()) { 956 field_val = field_val->in(1); 957 } else { 958 field_val = transform_later(new DecodeNNode(field_val, field_val->get_ptr_type())); 959 } 960 } 961 sfpt->add_req(field_val); 962 } 963 JVMState *jvms = sfpt->jvms(); 964 jvms->set_endoff(sfpt->req()); 965 // Now make a pass over the debug information replacing any references 966 // to the allocated object with "sobj" 967 int start = jvms->debug_start(); 968 int end = jvms->debug_end(); 969 sfpt->replace_edges_in_range(res, sobj, start, end); 970 _igvn._worklist.push(sfpt); 971 safepoints_done.append_if_missing(sfpt); // keep it for rollback 972 } 973 return true; 974 } 975 976 static void disconnect_projections(MultiNode* n, PhaseIterGVN& igvn) { 977 Node* ctl_proj = n->proj_out(TypeFunc::Control); 978 Node* mem_proj = n->proj_out(TypeFunc::Memory); 979 if (ctl_proj != NULL) { 980 igvn.replace_node(ctl_proj, n->in(0)); 981 } 982 if (mem_proj != NULL) { 983 igvn.replace_node(mem_proj, n->in(TypeFunc::Memory)); 984 } 985 } 986 987 // Process users of eliminated allocation. 988 void PhaseMacroExpand::process_users_of_allocation(CallNode *alloc) { 989 Node* res = alloc->result_cast(); 990 if (res != NULL) { 991 for (DUIterator_Last jmin, j = res->last_outs(jmin); j >= jmin; ) { 992 Node *use = res->last_out(j); 993 uint oc1 = res->outcnt(); 994 995 if (use->is_AddP()) { 996 for (DUIterator_Last kmin, k = use->last_outs(kmin); k >= kmin; ) { 997 Node *n = use->last_out(k); 998 uint oc2 = use->outcnt(); 999 if (n->is_Store()) { 1000 #ifdef ASSERT 1001 // Verify that there is no dependent MemBarVolatile nodes, 1002 // they should be removed during IGVN, see MemBarNode::Ideal(). 1003 for (DUIterator_Fast pmax, p = n->fast_outs(pmax); 1004 p < pmax; p++) { 1005 Node* mb = n->fast_out(p); 1006 assert(mb->is_Initialize() || !mb->is_MemBar() || 1007 mb->req() <= MemBarNode::Precedent || 1008 mb->in(MemBarNode::Precedent) != n, 1009 "MemBarVolatile should be eliminated for non-escaping object"); 1010 } 1011 #endif 1012 _igvn.replace_node(n, n->in(MemNode::Memory)); 1013 } else if (n->is_ArrayCopy()) { 1014 // Disconnect ArrayCopy node 1015 ArrayCopyNode* ac = n->as_ArrayCopy(); 1016 assert(ac->is_clonebasic(), "unexpected array copy kind"); 1017 Node* membar_after = ac->proj_out(TypeFunc::Control)->unique_ctrl_out(); 1018 disconnect_projections(ac, _igvn); 1019 assert(alloc->in(0)->is_Proj() && alloc->in(0)->in(0)->Opcode() == Op_MemBarCPUOrder, "mem barrier expected before allocation"); 1020 Node* membar_before = alloc->in(0)->in(0); 1021 disconnect_projections(membar_before->as_MemBar(), _igvn); 1022 if (membar_after->is_MemBar()) { 1023 disconnect_projections(membar_after->as_MemBar(), _igvn); 1024 } 1025 } else { 1026 eliminate_card_mark(n); 1027 } 1028 k -= (oc2 - use->outcnt()); 1029 } 1030 } else if (use->is_ArrayCopy()) { 1031 // Disconnect ArrayCopy node 1032 ArrayCopyNode* ac = use->as_ArrayCopy(); 1033 assert(ac->is_arraycopy_validated() || 1034 ac->is_copyof_validated() || 1035 ac->is_copyofrange_validated(), "unsupported"); 1036 CallProjections callprojs; 1037 ac->extract_projections(&callprojs, true); 1038 1039 _igvn.replace_node(callprojs.fallthrough_ioproj, ac->in(TypeFunc::I_O)); 1040 _igvn.replace_node(callprojs.fallthrough_memproj, ac->in(TypeFunc::Memory)); 1041 _igvn.replace_node(callprojs.fallthrough_catchproj, ac->in(TypeFunc::Control)); 1042 1043 // Set control to top. IGVN will remove the remaining projections 1044 ac->set_req(0, top()); 1045 ac->replace_edge(res, top()); 1046 1047 // Disconnect src right away: it can help find new 1048 // opportunities for allocation elimination 1049 Node* src = ac->in(ArrayCopyNode::Src); 1050 ac->replace_edge(src, top()); 1051 // src can be top at this point if src and dest of the 1052 // arraycopy were the same 1053 if (src->outcnt() == 0 && !src->is_top()) { 1054 _igvn.remove_dead_node(src); 1055 } 1056 1057 _igvn._worklist.push(ac); 1058 } else { 1059 eliminate_card_mark(use); 1060 } 1061 j -= (oc1 - res->outcnt()); 1062 } 1063 assert(res->outcnt() == 0, "all uses of allocated objects must be deleted"); 1064 _igvn.remove_dead_node(res); 1065 } 1066 1067 // 1068 // Process other users of allocation's projections 1069 // 1070 if (_resproj != NULL && _resproj->outcnt() != 0) { 1071 // First disconnect stores captured by Initialize node. 1072 // If Initialize node is eliminated first in the following code, 1073 // it will kill such stores and DUIterator_Last will assert. 1074 for (DUIterator_Fast jmax, j = _resproj->fast_outs(jmax); j < jmax; j++) { 1075 Node *use = _resproj->fast_out(j); 1076 if (use->is_AddP()) { 1077 // raw memory addresses used only by the initialization 1078 _igvn.replace_node(use, C->top()); 1079 --j; --jmax; 1080 } 1081 } 1082 for (DUIterator_Last jmin, j = _resproj->last_outs(jmin); j >= jmin; ) { 1083 Node *use = _resproj->last_out(j); 1084 uint oc1 = _resproj->outcnt(); 1085 if (use->is_Initialize()) { 1086 // Eliminate Initialize node. 1087 InitializeNode *init = use->as_Initialize(); 1088 assert(init->outcnt() <= 2, "only a control and memory projection expected"); 1089 Node *ctrl_proj = init->proj_out(TypeFunc::Control); 1090 if (ctrl_proj != NULL) { 1091 assert(init->in(TypeFunc::Control) == _fallthroughcatchproj, "allocation control projection"); 1092 _igvn.replace_node(ctrl_proj, _fallthroughcatchproj); 1093 } 1094 Node *mem_proj = init->proj_out(TypeFunc::Memory); 1095 if (mem_proj != NULL) { 1096 Node *mem = init->in(TypeFunc::Memory); 1097 #ifdef ASSERT 1098 if (mem->is_MergeMem()) { 1099 assert(mem->in(TypeFunc::Memory) == _memproj_fallthrough, "allocation memory projection"); 1100 } else { 1101 assert(mem == _memproj_fallthrough, "allocation memory projection"); 1102 } 1103 #endif 1104 _igvn.replace_node(mem_proj, mem); 1105 } 1106 } else { 1107 assert(false, "only Initialize or AddP expected"); 1108 } 1109 j -= (oc1 - _resproj->outcnt()); 1110 } 1111 } 1112 if (_fallthroughcatchproj != NULL) { 1113 _igvn.replace_node(_fallthroughcatchproj, alloc->in(TypeFunc::Control)); 1114 } 1115 if (_memproj_fallthrough != NULL) { 1116 _igvn.replace_node(_memproj_fallthrough, alloc->in(TypeFunc::Memory)); 1117 } 1118 if (_memproj_catchall != NULL) { 1119 _igvn.replace_node(_memproj_catchall, C->top()); 1120 } 1121 if (_ioproj_fallthrough != NULL) { 1122 _igvn.replace_node(_ioproj_fallthrough, alloc->in(TypeFunc::I_O)); 1123 } 1124 if (_ioproj_catchall != NULL) { 1125 _igvn.replace_node(_ioproj_catchall, C->top()); 1126 } 1127 if (_catchallcatchproj != NULL) { 1128 _igvn.replace_node(_catchallcatchproj, C->top()); 1129 } 1130 } 1131 1132 bool PhaseMacroExpand::eliminate_allocate_node(AllocateNode *alloc) { 1133 // Don't do scalar replacement if the frame can be popped by JVMTI: 1134 // if reallocation fails during deoptimization we'll pop all 1135 // interpreter frames for this compiled frame and that won't play 1136 // nice with JVMTI popframe. 1137 if (!EliminateAllocations || JvmtiExport::can_pop_frame() || !alloc->_is_non_escaping) { 1138 return false; 1139 } 1140 Node* klass = alloc->in(AllocateNode::KlassNode); 1141 const TypeKlassPtr* tklass = _igvn.type(klass)->is_klassptr(); 1142 Node* res = alloc->result_cast(); 1143 // Eliminate boxing allocations which are not used 1144 // regardless scalar replacable status. 1145 bool boxing_alloc = C->eliminate_boxing() && 1146 tklass->klass()->is_instance_klass() && 1147 tklass->klass()->as_instance_klass()->is_box_klass(); 1148 if (!alloc->_is_scalar_replaceable && (!boxing_alloc || (res != NULL))) { 1149 return false; 1150 } 1151 1152 extract_call_projections(alloc); 1153 1154 GrowableArray <SafePointNode *> safepoints; 1155 if (!can_eliminate_allocation(alloc, safepoints)) { 1156 return false; 1157 } 1158 1159 if (!alloc->_is_scalar_replaceable) { 1160 assert(res == NULL, "sanity"); 1161 // We can only eliminate allocation if all debug info references 1162 // are already replaced with SafePointScalarObject because 1163 // we can't search for a fields value without instance_id. 1164 if (safepoints.length() > 0) { 1165 return false; 1166 } 1167 } 1168 1169 if (!scalar_replacement(alloc, safepoints)) { 1170 return false; 1171 } 1172 1173 CompileLog* log = C->log(); 1174 if (log != NULL) { 1175 log->head("eliminate_allocation type='%d'", 1176 log->identify(tklass->klass())); 1177 JVMState* p = alloc->jvms(); 1178 while (p != NULL) { 1179 log->elem("jvms bci='%d' method='%d'", p->bci(), log->identify(p->method())); 1180 p = p->caller(); 1181 } 1182 log->tail("eliminate_allocation"); 1183 } 1184 1185 process_users_of_allocation(alloc); 1186 1187 #ifndef PRODUCT 1188 if (PrintEliminateAllocations) { 1189 if (alloc->is_AllocateArray()) 1190 tty->print_cr("++++ Eliminated: %d AllocateArray", alloc->_idx); 1191 else 1192 tty->print_cr("++++ Eliminated: %d Allocate", alloc->_idx); 1193 } 1194 #endif 1195 1196 return true; 1197 } 1198 1199 bool PhaseMacroExpand::eliminate_boxing_node(CallStaticJavaNode *boxing) { 1200 // EA should remove all uses of non-escaping boxing node. 1201 if (!C->eliminate_boxing() || boxing->proj_out(TypeFunc::Parms) != NULL) { 1202 return false; 1203 } 1204 1205 assert(boxing->result_cast() == NULL, "unexpected boxing node result"); 1206 1207 extract_call_projections(boxing); 1208 1209 const TypeTuple* r = boxing->tf()->range(); 1210 assert(r->cnt() > TypeFunc::Parms, "sanity"); 1211 const TypeInstPtr* t = r->field_at(TypeFunc::Parms)->isa_instptr(); 1212 assert(t != NULL, "sanity"); 1213 1214 CompileLog* log = C->log(); 1215 if (log != NULL) { 1216 log->head("eliminate_boxing type='%d'", 1217 log->identify(t->klass())); 1218 JVMState* p = boxing->jvms(); 1219 while (p != NULL) { 1220 log->elem("jvms bci='%d' method='%d'", p->bci(), log->identify(p->method())); 1221 p = p->caller(); 1222 } 1223 log->tail("eliminate_boxing"); 1224 } 1225 1226 process_users_of_allocation(boxing); 1227 1228 #ifndef PRODUCT 1229 if (PrintEliminateAllocations) { 1230 tty->print("++++ Eliminated: %d ", boxing->_idx); 1231 boxing->method()->print_short_name(tty); 1232 tty->cr(); 1233 } 1234 #endif 1235 1236 return true; 1237 } 1238 1239 //---------------------------set_eden_pointers------------------------- 1240 void PhaseMacroExpand::set_eden_pointers(Node* &eden_top_adr, Node* &eden_end_adr) { 1241 if (UseTLAB) { // Private allocation: load from TLS 1242 Node* thread = transform_later(new ThreadLocalNode()); 1243 int tlab_top_offset = in_bytes(JavaThread::tlab_top_offset()); 1244 int tlab_end_offset = in_bytes(JavaThread::tlab_end_offset()); 1245 eden_top_adr = basic_plus_adr(top()/*not oop*/, thread, tlab_top_offset); 1246 eden_end_adr = basic_plus_adr(top()/*not oop*/, thread, tlab_end_offset); 1247 } else { // Shared allocation: load from globals 1248 CollectedHeap* ch = Universe::heap(); 1249 address top_adr = (address)ch->top_addr(); 1250 address end_adr = (address)ch->end_addr(); 1251 eden_top_adr = makecon(TypeRawPtr::make(top_adr)); 1252 eden_end_adr = basic_plus_adr(eden_top_adr, end_adr - top_adr); 1253 } 1254 } 1255 1256 1257 Node* PhaseMacroExpand::make_load(Node* ctl, Node* mem, Node* base, int offset, const Type* value_type, BasicType bt) { 1258 Node* adr = basic_plus_adr(base, offset); 1259 const TypePtr* adr_type = adr->bottom_type()->is_ptr(); 1260 Node* value = LoadNode::make(_igvn, ctl, mem, adr, adr_type, value_type, bt, MemNode::unordered); 1261 transform_later(value); 1262 return value; 1263 } 1264 1265 1266 Node* PhaseMacroExpand::make_store(Node* ctl, Node* mem, Node* base, int offset, Node* value, BasicType bt) { 1267 Node* adr = basic_plus_adr(base, offset); 1268 mem = StoreNode::make(_igvn, ctl, mem, adr, NULL, value, bt, MemNode::unordered); 1269 transform_later(mem); 1270 return mem; 1271 } 1272 1273 //============================================================================= 1274 // 1275 // A L L O C A T I O N 1276 // 1277 // Allocation attempts to be fast in the case of frequent small objects. 1278 // It breaks down like this: 1279 // 1280 // 1) Size in doublewords is computed. This is a constant for objects and 1281 // variable for most arrays. Doubleword units are used to avoid size 1282 // overflow of huge doubleword arrays. We need doublewords in the end for 1283 // rounding. 1284 // 1285 // 2) Size is checked for being 'too large'. Too-large allocations will go 1286 // the slow path into the VM. The slow path can throw any required 1287 // exceptions, and does all the special checks for very large arrays. The 1288 // size test can constant-fold away for objects. For objects with 1289 // finalizers it constant-folds the otherway: you always go slow with 1290 // finalizers. 1291 // 1292 // 3) If NOT using TLABs, this is the contended loop-back point. 1293 // Load-Locked the heap top. If using TLABs normal-load the heap top. 1294 // 1295 // 4) Check that heap top + size*8 < max. If we fail go the slow ` route. 1296 // NOTE: "top+size*8" cannot wrap the 4Gig line! Here's why: for largish 1297 // "size*8" we always enter the VM, where "largish" is a constant picked small 1298 // enough that there's always space between the eden max and 4Gig (old space is 1299 // there so it's quite large) and large enough that the cost of entering the VM 1300 // is dwarfed by the cost to initialize the space. 1301 // 1302 // 5) If NOT using TLABs, Store-Conditional the adjusted heap top back 1303 // down. If contended, repeat at step 3. If using TLABs normal-store 1304 // adjusted heap top back down; there is no contention. 1305 // 1306 // 6) If !ZeroTLAB then Bulk-clear the object/array. Fill in klass & mark 1307 // fields. 1308 // 1309 // 7) Merge with the slow-path; cast the raw memory pointer to the correct 1310 // oop flavor. 1311 // 1312 //============================================================================= 1313 // FastAllocateSizeLimit value is in DOUBLEWORDS. 1314 // Allocations bigger than this always go the slow route. 1315 // This value must be small enough that allocation attempts that need to 1316 // trigger exceptions go the slow route. Also, it must be small enough so 1317 // that heap_top + size_in_bytes does not wrap around the 4Gig limit. 1318 //=============================================================================j// 1319 // %%% Here is an old comment from parseHelper.cpp; is it outdated? 1320 // The allocator will coalesce int->oop copies away. See comment in 1321 // coalesce.cpp about how this works. It depends critically on the exact 1322 // code shape produced here, so if you are changing this code shape 1323 // make sure the GC info for the heap-top is correct in and around the 1324 // slow-path call. 1325 // 1326 1327 void PhaseMacroExpand::expand_allocate_common( 1328 AllocateNode* alloc, // allocation node to be expanded 1329 Node* length, // array length for an array allocation 1330 const TypeFunc* slow_call_type, // Type of slow call 1331 address slow_call_address // Address of slow call 1332 ) 1333 { 1334 1335 Node* ctrl = alloc->in(TypeFunc::Control); 1336 Node* mem = alloc->in(TypeFunc::Memory); 1337 Node* i_o = alloc->in(TypeFunc::I_O); 1338 Node* size_in_bytes = alloc->in(AllocateNode::AllocSize); 1339 Node* klass_node = alloc->in(AllocateNode::KlassNode); 1340 Node* initial_slow_test = alloc->in(AllocateNode::InitialTest); 1341 1342 assert(ctrl != NULL, "must have control"); 1343 // We need a Region and corresponding Phi's to merge the slow-path and fast-path results. 1344 // they will not be used if "always_slow" is set 1345 enum { slow_result_path = 1, fast_result_path = 2 }; 1346 Node *result_region = NULL; 1347 Node *result_phi_rawmem = NULL; 1348 Node *result_phi_rawoop = NULL; 1349 Node *result_phi_i_o = NULL; 1350 1351 // The initial slow comparison is a size check, the comparison 1352 // we want to do is a BoolTest::gt 1353 bool always_slow = false; 1354 int tv = _igvn.find_int_con(initial_slow_test, -1); 1355 if (tv >= 0) { 1356 always_slow = (tv == 1); 1357 initial_slow_test = NULL; 1358 } else { 1359 initial_slow_test = BoolNode::make_predicate(initial_slow_test, &_igvn); 1360 } 1361 1362 if (C->env()->dtrace_alloc_probes() || 1363 (!UseTLAB && !Universe::heap()->supports_inline_contig_alloc())) { 1364 // Force slow-path allocation 1365 always_slow = true; 1366 initial_slow_test = NULL; 1367 } 1368 1369 1370 enum { too_big_or_final_path = 1, need_gc_path = 2 }; 1371 Node *slow_region = NULL; 1372 Node *toobig_false = ctrl; 1373 1374 assert (initial_slow_test == NULL || !always_slow, "arguments must be consistent"); 1375 // generate the initial test if necessary 1376 if (initial_slow_test != NULL ) { 1377 slow_region = new RegionNode(3); 1378 1379 // Now make the initial failure test. Usually a too-big test but 1380 // might be a TRUE for finalizers or a fancy class check for 1381 // newInstance0. 1382 IfNode *toobig_iff = new IfNode(ctrl, initial_slow_test, PROB_MIN, COUNT_UNKNOWN); 1383 transform_later(toobig_iff); 1384 // Plug the failing-too-big test into the slow-path region 1385 Node *toobig_true = new IfTrueNode( toobig_iff ); 1386 transform_later(toobig_true); 1387 slow_region ->init_req( too_big_or_final_path, toobig_true ); 1388 toobig_false = new IfFalseNode( toobig_iff ); 1389 transform_later(toobig_false); 1390 } else { // No initial test, just fall into next case 1391 toobig_false = ctrl; 1392 debug_only(slow_region = NodeSentinel); 1393 } 1394 1395 Node *slow_mem = mem; // save the current memory state for slow path 1396 // generate the fast allocation code unless we know that the initial test will always go slow 1397 if (!always_slow) { 1398 // Fast path modifies only raw memory. 1399 if (mem->is_MergeMem()) { 1400 mem = mem->as_MergeMem()->memory_at(Compile::AliasIdxRaw); 1401 } 1402 1403 Node* eden_top_adr; 1404 Node* eden_end_adr; 1405 1406 set_eden_pointers(eden_top_adr, eden_end_adr); 1407 1408 // Load Eden::end. Loop invariant and hoisted. 1409 // 1410 // Note: We set the control input on "eden_end" and "old_eden_top" when using 1411 // a TLAB to work around a bug where these values were being moved across 1412 // a safepoint. These are not oops, so they cannot be include in the oop 1413 // map, but they can be changed by a GC. The proper way to fix this would 1414 // be to set the raw memory state when generating a SafepointNode. However 1415 // this will require extensive changes to the loop optimization in order to 1416 // prevent a degradation of the optimization. 1417 // See comment in memnode.hpp, around line 227 in class LoadPNode. 1418 Node *eden_end = make_load(ctrl, mem, eden_end_adr, 0, TypeRawPtr::BOTTOM, T_ADDRESS); 1419 1420 // allocate the Region and Phi nodes for the result 1421 result_region = new RegionNode(3); 1422 result_phi_rawmem = new PhiNode(result_region, Type::MEMORY, TypeRawPtr::BOTTOM); 1423 result_phi_rawoop = new PhiNode(result_region, TypeRawPtr::BOTTOM); 1424 result_phi_i_o = new PhiNode(result_region, Type::ABIO); // I/O is used for Prefetch 1425 1426 // We need a Region for the loop-back contended case. 1427 enum { fall_in_path = 1, contended_loopback_path = 2 }; 1428 Node *contended_region; 1429 Node *contended_phi_rawmem; 1430 if (UseTLAB) { 1431 contended_region = toobig_false; 1432 contended_phi_rawmem = mem; 1433 } else { 1434 contended_region = new RegionNode(3); 1435 contended_phi_rawmem = new PhiNode(contended_region, Type::MEMORY, TypeRawPtr::BOTTOM); 1436 // Now handle the passing-too-big test. We fall into the contended 1437 // loop-back merge point. 1438 contended_region ->init_req(fall_in_path, toobig_false); 1439 contended_phi_rawmem->init_req(fall_in_path, mem); 1440 transform_later(contended_region); 1441 transform_later(contended_phi_rawmem); 1442 } 1443 1444 // Load(-locked) the heap top. 1445 // See note above concerning the control input when using a TLAB 1446 Node *old_eden_top = UseTLAB 1447 ? new LoadPNode (ctrl, contended_phi_rawmem, eden_top_adr, TypeRawPtr::BOTTOM, TypeRawPtr::BOTTOM, MemNode::unordered) 1448 : new LoadPLockedNode(contended_region, contended_phi_rawmem, eden_top_adr, MemNode::acquire); 1449 1450 transform_later(old_eden_top); 1451 // Add to heap top to get a new heap top 1452 Node *new_eden_top = new AddPNode(top(), old_eden_top, size_in_bytes); 1453 transform_later(new_eden_top); 1454 // Check for needing a GC; compare against heap end 1455 Node *needgc_cmp = new CmpPNode(new_eden_top, eden_end); 1456 transform_later(needgc_cmp); 1457 Node *needgc_bol = new BoolNode(needgc_cmp, BoolTest::ge); 1458 transform_later(needgc_bol); 1459 IfNode *needgc_iff = new IfNode(contended_region, needgc_bol, PROB_UNLIKELY_MAG(4), COUNT_UNKNOWN); 1460 transform_later(needgc_iff); 1461 1462 // Plug the failing-heap-space-need-gc test into the slow-path region 1463 Node *needgc_true = new IfTrueNode(needgc_iff); 1464 transform_later(needgc_true); 1465 if (initial_slow_test) { 1466 slow_region->init_req(need_gc_path, needgc_true); 1467 // This completes all paths into the slow merge point 1468 transform_later(slow_region); 1469 } else { // No initial slow path needed! 1470 // Just fall from the need-GC path straight into the VM call. 1471 slow_region = needgc_true; 1472 } 1473 // No need for a GC. Setup for the Store-Conditional 1474 Node *needgc_false = new IfFalseNode(needgc_iff); 1475 transform_later(needgc_false); 1476 1477 // Grab regular I/O before optional prefetch may change it. 1478 // Slow-path does no I/O so just set it to the original I/O. 1479 result_phi_i_o->init_req(slow_result_path, i_o); 1480 1481 i_o = prefetch_allocation(i_o, needgc_false, contended_phi_rawmem, 1482 old_eden_top, new_eden_top, length); 1483 1484 // Name successful fast-path variables 1485 Node* fast_oop = old_eden_top; 1486 Node* fast_oop_ctrl; 1487 Node* fast_oop_rawmem; 1488 1489 // Store (-conditional) the modified eden top back down. 1490 // StorePConditional produces flags for a test PLUS a modified raw 1491 // memory state. 1492 if (UseTLAB) { 1493 Node* store_eden_top = 1494 new StorePNode(needgc_false, contended_phi_rawmem, eden_top_adr, 1495 TypeRawPtr::BOTTOM, new_eden_top, MemNode::unordered); 1496 transform_later(store_eden_top); 1497 fast_oop_ctrl = needgc_false; // No contention, so this is the fast path 1498 fast_oop_rawmem = store_eden_top; 1499 } else { 1500 Node* store_eden_top = 1501 new StorePConditionalNode(needgc_false, contended_phi_rawmem, eden_top_adr, 1502 new_eden_top, fast_oop/*old_eden_top*/); 1503 transform_later(store_eden_top); 1504 Node *contention_check = new BoolNode(store_eden_top, BoolTest::ne); 1505 transform_later(contention_check); 1506 store_eden_top = new SCMemProjNode(store_eden_top); 1507 transform_later(store_eden_top); 1508 1509 // If not using TLABs, check to see if there was contention. 1510 IfNode *contention_iff = new IfNode (needgc_false, contention_check, PROB_MIN, COUNT_UNKNOWN); 1511 transform_later(contention_iff); 1512 Node *contention_true = new IfTrueNode(contention_iff); 1513 transform_later(contention_true); 1514 // If contention, loopback and try again. 1515 contended_region->init_req(contended_loopback_path, contention_true); 1516 contended_phi_rawmem->init_req(contended_loopback_path, store_eden_top); 1517 1518 // Fast-path succeeded with no contention! 1519 Node *contention_false = new IfFalseNode(contention_iff); 1520 transform_later(contention_false); 1521 fast_oop_ctrl = contention_false; 1522 1523 // Bump total allocated bytes for this thread 1524 Node* thread = new ThreadLocalNode(); 1525 transform_later(thread); 1526 Node* alloc_bytes_adr = basic_plus_adr(top()/*not oop*/, thread, 1527 in_bytes(JavaThread::allocated_bytes_offset())); 1528 Node* alloc_bytes = make_load(fast_oop_ctrl, store_eden_top, alloc_bytes_adr, 1529 0, TypeLong::LONG, T_LONG); 1530 #ifdef _LP64 1531 Node* alloc_size = size_in_bytes; 1532 #else 1533 Node* alloc_size = new ConvI2LNode(size_in_bytes); 1534 transform_later(alloc_size); 1535 #endif 1536 Node* new_alloc_bytes = new AddLNode(alloc_bytes, alloc_size); 1537 transform_later(new_alloc_bytes); 1538 fast_oop_rawmem = make_store(fast_oop_ctrl, store_eden_top, alloc_bytes_adr, 1539 0, new_alloc_bytes, T_LONG); 1540 } 1541 1542 InitializeNode* init = alloc->initialization(); 1543 fast_oop_rawmem = initialize_object(alloc, 1544 fast_oop_ctrl, fast_oop_rawmem, fast_oop, 1545 klass_node, length, size_in_bytes); 1546 1547 // If initialization is performed by an array copy, any required 1548 // MemBarStoreStore was already added. If the object does not 1549 // escape no need for a MemBarStoreStore. If the object does not 1550 // escape in its initializer and memory barrier (MemBarStoreStore or 1551 // stronger) is already added at exit of initializer, also no need 1552 // for a MemBarStoreStore. Otherwise we need a MemBarStoreStore 1553 // so that stores that initialize this object can't be reordered 1554 // with a subsequent store that makes this object accessible by 1555 // other threads. 1556 // Other threads include java threads and JVM internal threads 1557 // (for example concurrent GC threads). Current concurrent GC 1558 // implementation: CMS and G1 will not scan newly created object, 1559 // so it's safe to skip storestore barrier when allocation does 1560 // not escape. 1561 if (!alloc->does_not_escape_thread() && 1562 !alloc->is_allocation_MemBar_redundant() && 1563 (init == NULL || !init->is_complete_with_arraycopy())) { 1564 if (init == NULL || init->req() < InitializeNode::RawStores) { 1565 // No InitializeNode or no stores captured by zeroing 1566 // elimination. Simply add the MemBarStoreStore after object 1567 // initialization. 1568 MemBarNode* mb = MemBarNode::make(C, Op_MemBarStoreStore, Compile::AliasIdxBot); 1569 transform_later(mb); 1570 1571 mb->init_req(TypeFunc::Memory, fast_oop_rawmem); 1572 mb->init_req(TypeFunc::Control, fast_oop_ctrl); 1573 fast_oop_ctrl = new ProjNode(mb,TypeFunc::Control); 1574 transform_later(fast_oop_ctrl); 1575 fast_oop_rawmem = new ProjNode(mb,TypeFunc::Memory); 1576 transform_later(fast_oop_rawmem); 1577 } else { 1578 // Add the MemBarStoreStore after the InitializeNode so that 1579 // all stores performing the initialization that were moved 1580 // before the InitializeNode happen before the storestore 1581 // barrier. 1582 1583 Node* init_ctrl = init->proj_out(TypeFunc::Control); 1584 Node* init_mem = init->proj_out(TypeFunc::Memory); 1585 1586 MemBarNode* mb = MemBarNode::make(C, Op_MemBarStoreStore, Compile::AliasIdxBot); 1587 transform_later(mb); 1588 1589 Node* ctrl = new ProjNode(init,TypeFunc::Control); 1590 transform_later(ctrl); 1591 Node* mem = new ProjNode(init,TypeFunc::Memory); 1592 transform_later(mem); 1593 1594 // The MemBarStoreStore depends on control and memory coming 1595 // from the InitializeNode 1596 mb->init_req(TypeFunc::Memory, mem); 1597 mb->init_req(TypeFunc::Control, ctrl); 1598 1599 ctrl = new ProjNode(mb,TypeFunc::Control); 1600 transform_later(ctrl); 1601 mem = new ProjNode(mb,TypeFunc::Memory); 1602 transform_later(mem); 1603 1604 // All nodes that depended on the InitializeNode for control 1605 // and memory must now depend on the MemBarNode that itself 1606 // depends on the InitializeNode 1607 if (init_ctrl != NULL) { 1608 _igvn.replace_node(init_ctrl, ctrl); 1609 } 1610 if (init_mem != NULL) { 1611 _igvn.replace_node(init_mem, mem); 1612 } 1613 } 1614 } 1615 1616 if (C->env()->dtrace_extended_probes()) { 1617 // Slow-path call 1618 int size = TypeFunc::Parms + 2; 1619 CallLeafNode *call = new CallLeafNode(OptoRuntime::dtrace_object_alloc_Type(), 1620 CAST_FROM_FN_PTR(address, SharedRuntime::dtrace_object_alloc_base), 1621 "dtrace_object_alloc", 1622 TypeRawPtr::BOTTOM); 1623 1624 // Get base of thread-local storage area 1625 Node* thread = new ThreadLocalNode(); 1626 transform_later(thread); 1627 1628 call->init_req(TypeFunc::Parms+0, thread); 1629 call->init_req(TypeFunc::Parms+1, fast_oop); 1630 call->init_req(TypeFunc::Control, fast_oop_ctrl); 1631 call->init_req(TypeFunc::I_O , top()); // does no i/o 1632 call->init_req(TypeFunc::Memory , fast_oop_rawmem); 1633 call->init_req(TypeFunc::ReturnAdr, alloc->in(TypeFunc::ReturnAdr)); 1634 call->init_req(TypeFunc::FramePtr, alloc->in(TypeFunc::FramePtr)); 1635 transform_later(call); 1636 fast_oop_ctrl = new ProjNode(call,TypeFunc::Control); 1637 transform_later(fast_oop_ctrl); 1638 fast_oop_rawmem = new ProjNode(call,TypeFunc::Memory); 1639 transform_later(fast_oop_rawmem); 1640 } 1641 1642 // Plug in the successful fast-path into the result merge point 1643 result_region ->init_req(fast_result_path, fast_oop_ctrl); 1644 result_phi_rawoop->init_req(fast_result_path, fast_oop); 1645 result_phi_i_o ->init_req(fast_result_path, i_o); 1646 result_phi_rawmem->init_req(fast_result_path, fast_oop_rawmem); 1647 } else { 1648 slow_region = ctrl; 1649 result_phi_i_o = i_o; // Rename it to use in the following code. 1650 } 1651 1652 // Generate slow-path call 1653 CallNode *call = new CallStaticJavaNode(slow_call_type, slow_call_address, 1654 OptoRuntime::stub_name(slow_call_address), 1655 alloc->jvms()->bci(), 1656 TypePtr::BOTTOM); 1657 call->init_req( TypeFunc::Control, slow_region ); 1658 call->init_req( TypeFunc::I_O , top() ) ; // does no i/o 1659 call->init_req( TypeFunc::Memory , slow_mem ); // may gc ptrs 1660 call->init_req( TypeFunc::ReturnAdr, alloc->in(TypeFunc::ReturnAdr) ); 1661 call->init_req( TypeFunc::FramePtr, alloc->in(TypeFunc::FramePtr) ); 1662 1663 call->init_req(TypeFunc::Parms+0, klass_node); 1664 if (length != NULL) { 1665 call->init_req(TypeFunc::Parms+1, length); 1666 } 1667 1668 // Copy debug information and adjust JVMState information, then replace 1669 // allocate node with the call 1670 copy_call_debug_info((CallNode *) alloc, call); 1671 if (!always_slow) { 1672 call->set_cnt(PROB_UNLIKELY_MAG(4)); // Same effect as RC_UNCOMMON. 1673 } else { 1674 // Hook i_o projection to avoid its elimination during allocation 1675 // replacement (when only a slow call is generated). 1676 call->set_req(TypeFunc::I_O, result_phi_i_o); 1677 } 1678 _igvn.replace_node(alloc, call); 1679 transform_later(call); 1680 1681 // Identify the output projections from the allocate node and 1682 // adjust any references to them. 1683 // The control and io projections look like: 1684 // 1685 // v---Proj(ctrl) <-----+ v---CatchProj(ctrl) 1686 // Allocate Catch 1687 // ^---Proj(io) <-------+ ^---CatchProj(io) 1688 // 1689 // We are interested in the CatchProj nodes. 1690 // 1691 extract_call_projections(call); 1692 1693 // An allocate node has separate memory projections for the uses on 1694 // the control and i_o paths. Replace the control memory projection with 1695 // result_phi_rawmem (unless we are only generating a slow call when 1696 // both memory projections are combined) 1697 if (!always_slow && _memproj_fallthrough != NULL) { 1698 for (DUIterator_Fast imax, i = _memproj_fallthrough->fast_outs(imax); i < imax; i++) { 1699 Node *use = _memproj_fallthrough->fast_out(i); 1700 _igvn.rehash_node_delayed(use); 1701 imax -= replace_input(use, _memproj_fallthrough, result_phi_rawmem); 1702 // back up iterator 1703 --i; 1704 } 1705 } 1706 // Now change uses of _memproj_catchall to use _memproj_fallthrough and delete 1707 // _memproj_catchall so we end up with a call that has only 1 memory projection. 1708 if (_memproj_catchall != NULL ) { 1709 if (_memproj_fallthrough == NULL) { 1710 _memproj_fallthrough = new ProjNode(call, TypeFunc::Memory); 1711 transform_later(_memproj_fallthrough); 1712 } 1713 for (DUIterator_Fast imax, i = _memproj_catchall->fast_outs(imax); i < imax; i++) { 1714 Node *use = _memproj_catchall->fast_out(i); 1715 _igvn.rehash_node_delayed(use); 1716 imax -= replace_input(use, _memproj_catchall, _memproj_fallthrough); 1717 // back up iterator 1718 --i; 1719 } 1720 assert(_memproj_catchall->outcnt() == 0, "all uses must be deleted"); 1721 _igvn.remove_dead_node(_memproj_catchall); 1722 } 1723 1724 // An allocate node has separate i_o projections for the uses on the control 1725 // and i_o paths. Always replace the control i_o projection with result i_o 1726 // otherwise incoming i_o become dead when only a slow call is generated 1727 // (it is different from memory projections where both projections are 1728 // combined in such case). 1729 if (_ioproj_fallthrough != NULL) { 1730 for (DUIterator_Fast imax, i = _ioproj_fallthrough->fast_outs(imax); i < imax; i++) { 1731 Node *use = _ioproj_fallthrough->fast_out(i); 1732 _igvn.rehash_node_delayed(use); 1733 imax -= replace_input(use, _ioproj_fallthrough, result_phi_i_o); 1734 // back up iterator 1735 --i; 1736 } 1737 } 1738 // Now change uses of _ioproj_catchall to use _ioproj_fallthrough and delete 1739 // _ioproj_catchall so we end up with a call that has only 1 i_o projection. 1740 if (_ioproj_catchall != NULL ) { 1741 if (_ioproj_fallthrough == NULL) { 1742 _ioproj_fallthrough = new ProjNode(call, TypeFunc::I_O); 1743 transform_later(_ioproj_fallthrough); 1744 } 1745 for (DUIterator_Fast imax, i = _ioproj_catchall->fast_outs(imax); i < imax; i++) { 1746 Node *use = _ioproj_catchall->fast_out(i); 1747 _igvn.rehash_node_delayed(use); 1748 imax -= replace_input(use, _ioproj_catchall, _ioproj_fallthrough); 1749 // back up iterator 1750 --i; 1751 } 1752 assert(_ioproj_catchall->outcnt() == 0, "all uses must be deleted"); 1753 _igvn.remove_dead_node(_ioproj_catchall); 1754 } 1755 1756 // if we generated only a slow call, we are done 1757 if (always_slow) { 1758 // Now we can unhook i_o. 1759 if (result_phi_i_o->outcnt() > 1) { 1760 call->set_req(TypeFunc::I_O, top()); 1761 } else { 1762 assert(result_phi_i_o->unique_ctrl_out() == call, ""); 1763 // Case of new array with negative size known during compilation. 1764 // AllocateArrayNode::Ideal() optimization disconnect unreachable 1765 // following code since call to runtime will throw exception. 1766 // As result there will be no users of i_o after the call. 1767 // Leave i_o attached to this call to avoid problems in preceding graph. 1768 } 1769 return; 1770 } 1771 1772 1773 if (_fallthroughcatchproj != NULL) { 1774 ctrl = _fallthroughcatchproj->clone(); 1775 transform_later(ctrl); 1776 _igvn.replace_node(_fallthroughcatchproj, result_region); 1777 } else { 1778 ctrl = top(); 1779 } 1780 Node *slow_result; 1781 if (_resproj == NULL) { 1782 // no uses of the allocation result 1783 slow_result = top(); 1784 } else { 1785 slow_result = _resproj->clone(); 1786 transform_later(slow_result); 1787 _igvn.replace_node(_resproj, result_phi_rawoop); 1788 } 1789 1790 // Plug slow-path into result merge point 1791 result_region ->init_req( slow_result_path, ctrl ); 1792 result_phi_rawoop->init_req( slow_result_path, slow_result); 1793 result_phi_rawmem->init_req( slow_result_path, _memproj_fallthrough ); 1794 transform_later(result_region); 1795 transform_later(result_phi_rawoop); 1796 transform_later(result_phi_rawmem); 1797 transform_later(result_phi_i_o); 1798 // This completes all paths into the result merge point 1799 } 1800 1801 1802 // Helper for PhaseMacroExpand::expand_allocate_common. 1803 // Initializes the newly-allocated storage. 1804 Node* 1805 PhaseMacroExpand::initialize_object(AllocateNode* alloc, 1806 Node* control, Node* rawmem, Node* object, 1807 Node* klass_node, Node* length, 1808 Node* size_in_bytes) { 1809 InitializeNode* init = alloc->initialization(); 1810 // Store the klass & mark bits 1811 Node* mark_node = NULL; 1812 // For now only enable fast locking for non-array types 1813 if (UseBiasedLocking && (length == NULL)) { 1814 mark_node = make_load(control, rawmem, klass_node, in_bytes(Klass::prototype_header_offset()), TypeRawPtr::BOTTOM, T_ADDRESS); 1815 } else { 1816 mark_node = makecon(TypeRawPtr::make((address)markOopDesc::prototype())); 1817 } 1818 rawmem = make_store(control, rawmem, object, oopDesc::mark_offset_in_bytes(), mark_node, T_ADDRESS); 1819 1820 rawmem = make_store(control, rawmem, object, oopDesc::klass_offset_in_bytes(), klass_node, T_METADATA); 1821 int header_size = alloc->minimum_header_size(); // conservatively small 1822 1823 // Array length 1824 if (length != NULL) { // Arrays need length field 1825 rawmem = make_store(control, rawmem, object, arrayOopDesc::length_offset_in_bytes(), length, T_INT); 1826 // conservatively small header size: 1827 header_size = arrayOopDesc::base_offset_in_bytes(T_BYTE); 1828 ciKlass* k = _igvn.type(klass_node)->is_klassptr()->klass(); 1829 if (k->is_array_klass()) // we know the exact header size in most cases: 1830 header_size = Klass::layout_helper_header_size(k->layout_helper()); 1831 } 1832 1833 // Clear the object body, if necessary. 1834 if (init == NULL) { 1835 // The init has somehow disappeared; be cautious and clear everything. 1836 // 1837 // This can happen if a node is allocated but an uncommon trap occurs 1838 // immediately. In this case, the Initialize gets associated with the 1839 // trap, and may be placed in a different (outer) loop, if the Allocate 1840 // is in a loop. If (this is rare) the inner loop gets unrolled, then 1841 // there can be two Allocates to one Initialize. The answer in all these 1842 // edge cases is safety first. It is always safe to clear immediately 1843 // within an Allocate, and then (maybe or maybe not) clear some more later. 1844 if (!(UseTLAB && ZeroTLAB)) { 1845 rawmem = ClearArrayNode::clear_memory(control, rawmem, object, 1846 header_size, size_in_bytes, 1847 &_igvn); 1848 } 1849 } else { 1850 if (!init->is_complete()) { 1851 // Try to win by zeroing only what the init does not store. 1852 // We can also try to do some peephole optimizations, 1853 // such as combining some adjacent subword stores. 1854 rawmem = init->complete_stores(control, rawmem, object, 1855 header_size, size_in_bytes, &_igvn); 1856 } 1857 // We have no more use for this link, since the AllocateNode goes away: 1858 init->set_req(InitializeNode::RawAddress, top()); 1859 // (If we keep the link, it just confuses the register allocator, 1860 // who thinks he sees a real use of the address by the membar.) 1861 } 1862 1863 return rawmem; 1864 } 1865 1866 // Generate prefetch instructions for next allocations. 1867 Node* PhaseMacroExpand::prefetch_allocation(Node* i_o, Node*& needgc_false, 1868 Node*& contended_phi_rawmem, 1869 Node* old_eden_top, Node* new_eden_top, 1870 Node* length) { 1871 enum { fall_in_path = 1, pf_path = 2 }; 1872 if( UseTLAB && AllocatePrefetchStyle == 2 ) { 1873 // Generate prefetch allocation with watermark check. 1874 // As an allocation hits the watermark, we will prefetch starting 1875 // at a "distance" away from watermark. 1876 1877 Node *pf_region = new RegionNode(3); 1878 Node *pf_phi_rawmem = new PhiNode( pf_region, Type::MEMORY, 1879 TypeRawPtr::BOTTOM ); 1880 // I/O is used for Prefetch 1881 Node *pf_phi_abio = new PhiNode( pf_region, Type::ABIO ); 1882 1883 Node *thread = new ThreadLocalNode(); 1884 transform_later(thread); 1885 1886 Node *eden_pf_adr = new AddPNode( top()/*not oop*/, thread, 1887 _igvn.MakeConX(in_bytes(JavaThread::tlab_pf_top_offset())) ); 1888 transform_later(eden_pf_adr); 1889 1890 Node *old_pf_wm = new LoadPNode(needgc_false, 1891 contended_phi_rawmem, eden_pf_adr, 1892 TypeRawPtr::BOTTOM, TypeRawPtr::BOTTOM, 1893 MemNode::unordered); 1894 transform_later(old_pf_wm); 1895 1896 // check against new_eden_top 1897 Node *need_pf_cmp = new CmpPNode( new_eden_top, old_pf_wm ); 1898 transform_later(need_pf_cmp); 1899 Node *need_pf_bol = new BoolNode( need_pf_cmp, BoolTest::ge ); 1900 transform_later(need_pf_bol); 1901 IfNode *need_pf_iff = new IfNode( needgc_false, need_pf_bol, 1902 PROB_UNLIKELY_MAG(4), COUNT_UNKNOWN ); 1903 transform_later(need_pf_iff); 1904 1905 // true node, add prefetchdistance 1906 Node *need_pf_true = new IfTrueNode( need_pf_iff ); 1907 transform_later(need_pf_true); 1908 1909 Node *need_pf_false = new IfFalseNode( need_pf_iff ); 1910 transform_later(need_pf_false); 1911 1912 Node *new_pf_wmt = new AddPNode( top(), old_pf_wm, 1913 _igvn.MakeConX(AllocatePrefetchDistance) ); 1914 transform_later(new_pf_wmt ); 1915 new_pf_wmt->set_req(0, need_pf_true); 1916 1917 Node *store_new_wmt = new StorePNode(need_pf_true, 1918 contended_phi_rawmem, eden_pf_adr, 1919 TypeRawPtr::BOTTOM, new_pf_wmt, 1920 MemNode::unordered); 1921 transform_later(store_new_wmt); 1922 1923 // adding prefetches 1924 pf_phi_abio->init_req( fall_in_path, i_o ); 1925 1926 Node *prefetch_adr; 1927 Node *prefetch; 1928 uint lines = (length != NULL) ? AllocatePrefetchLines : AllocateInstancePrefetchLines; 1929 uint step_size = AllocatePrefetchStepSize; 1930 uint distance = 0; 1931 1932 for ( uint i = 0; i < lines; i++ ) { 1933 prefetch_adr = new AddPNode( old_pf_wm, new_pf_wmt, 1934 _igvn.MakeConX(distance) ); 1935 transform_later(prefetch_adr); 1936 prefetch = new PrefetchAllocationNode( i_o, prefetch_adr ); 1937 transform_later(prefetch); 1938 distance += step_size; 1939 i_o = prefetch; 1940 } 1941 pf_phi_abio->set_req( pf_path, i_o ); 1942 1943 pf_region->init_req( fall_in_path, need_pf_false ); 1944 pf_region->init_req( pf_path, need_pf_true ); 1945 1946 pf_phi_rawmem->init_req( fall_in_path, contended_phi_rawmem ); 1947 pf_phi_rawmem->init_req( pf_path, store_new_wmt ); 1948 1949 transform_later(pf_region); 1950 transform_later(pf_phi_rawmem); 1951 transform_later(pf_phi_abio); 1952 1953 needgc_false = pf_region; 1954 contended_phi_rawmem = pf_phi_rawmem; 1955 i_o = pf_phi_abio; 1956 } else if( UseTLAB && AllocatePrefetchStyle == 3 ) { 1957 // Insert a prefetch instruction for each allocation. 1958 // This code is used to generate 1 prefetch instruction per cache line. 1959 1960 // Generate several prefetch instructions. 1961 uint lines = (length != NULL) ? AllocatePrefetchLines : AllocateInstancePrefetchLines; 1962 uint step_size = AllocatePrefetchStepSize; 1963 uint distance = AllocatePrefetchDistance; 1964 1965 // Next cache address. 1966 Node *cache_adr = new AddPNode(old_eden_top, old_eden_top, 1967 _igvn.MakeConX(step_size + distance)); 1968 transform_later(cache_adr); 1969 cache_adr = new CastP2XNode(needgc_false, cache_adr); 1970 transform_later(cache_adr); 1971 // Address is aligned to execute prefetch to the beginning of cache line size 1972 // (it is important when BIS instruction is used on SPARC as prefetch). 1973 Node* mask = _igvn.MakeConX(~(intptr_t)(step_size-1)); 1974 cache_adr = new AndXNode(cache_adr, mask); 1975 transform_later(cache_adr); 1976 cache_adr = new CastX2PNode(cache_adr); 1977 transform_later(cache_adr); 1978 1979 // Prefetch 1980 Node *prefetch = new PrefetchAllocationNode( contended_phi_rawmem, cache_adr ); 1981 prefetch->set_req(0, needgc_false); 1982 transform_later(prefetch); 1983 contended_phi_rawmem = prefetch; 1984 Node *prefetch_adr; 1985 distance = step_size; 1986 for ( uint i = 1; i < lines; i++ ) { 1987 prefetch_adr = new AddPNode( cache_adr, cache_adr, 1988 _igvn.MakeConX(distance) ); 1989 transform_later(prefetch_adr); 1990 prefetch = new PrefetchAllocationNode( contended_phi_rawmem, prefetch_adr ); 1991 transform_later(prefetch); 1992 distance += step_size; 1993 contended_phi_rawmem = prefetch; 1994 } 1995 } else if( AllocatePrefetchStyle > 0 ) { 1996 // Insert a prefetch for each allocation only on the fast-path 1997 Node *prefetch_adr; 1998 Node *prefetch; 1999 // Generate several prefetch instructions. 2000 uint lines = (length != NULL) ? AllocatePrefetchLines : AllocateInstancePrefetchLines; 2001 uint step_size = AllocatePrefetchStepSize; 2002 uint distance = AllocatePrefetchDistance; 2003 for ( uint i = 0; i < lines; i++ ) { 2004 prefetch_adr = new AddPNode( old_eden_top, new_eden_top, 2005 _igvn.MakeConX(distance) ); 2006 transform_later(prefetch_adr); 2007 prefetch = new PrefetchAllocationNode( i_o, prefetch_adr ); 2008 // Do not let it float too high, since if eden_top == eden_end, 2009 // both might be null. 2010 if( i == 0 ) { // Set control for first prefetch, next follows it 2011 prefetch->init_req(0, needgc_false); 2012 } 2013 transform_later(prefetch); 2014 distance += step_size; 2015 i_o = prefetch; 2016 } 2017 } 2018 return i_o; 2019 } 2020 2021 2022 void PhaseMacroExpand::expand_allocate(AllocateNode *alloc) { 2023 expand_allocate_common(alloc, NULL, 2024 OptoRuntime::new_instance_Type(), 2025 OptoRuntime::new_instance_Java()); 2026 } 2027 2028 void PhaseMacroExpand::expand_allocate_array(AllocateArrayNode *alloc) { 2029 Node* length = alloc->in(AllocateNode::ALength); 2030 InitializeNode* init = alloc->initialization(); 2031 Node* klass_node = alloc->in(AllocateNode::KlassNode); 2032 ciKlass* k = _igvn.type(klass_node)->is_klassptr()->klass(); 2033 address slow_call_address; // Address of slow call 2034 if (init != NULL && init->is_complete_with_arraycopy() && 2035 k->is_type_array_klass()) { 2036 // Don't zero type array during slow allocation in VM since 2037 // it will be initialized later by arraycopy in compiled code. 2038 slow_call_address = OptoRuntime::new_array_nozero_Java(); 2039 } else { 2040 slow_call_address = OptoRuntime::new_array_Java(); 2041 } 2042 expand_allocate_common(alloc, length, 2043 OptoRuntime::new_array_Type(), 2044 slow_call_address); 2045 } 2046 2047 //-------------------mark_eliminated_box---------------------------------- 2048 // 2049 // During EA obj may point to several objects but after few ideal graph 2050 // transformations (CCP) it may point to only one non escaping object 2051 // (but still using phi), corresponding locks and unlocks will be marked 2052 // for elimination. Later obj could be replaced with a new node (new phi) 2053 // and which does not have escape information. And later after some graph 2054 // reshape other locks and unlocks (which were not marked for elimination 2055 // before) are connected to this new obj (phi) but they still will not be 2056 // marked for elimination since new obj has no escape information. 2057 // Mark all associated (same box and obj) lock and unlock nodes for 2058 // elimination if some of them marked already. 2059 void PhaseMacroExpand::mark_eliminated_box(Node* oldbox, Node* obj) { 2060 if (oldbox->as_BoxLock()->is_eliminated()) 2061 return; // This BoxLock node was processed already. 2062 2063 // New implementation (EliminateNestedLocks) has separate BoxLock 2064 // node for each locked region so mark all associated locks/unlocks as 2065 // eliminated even if different objects are referenced in one locked region 2066 // (for example, OSR compilation of nested loop inside locked scope). 2067 if (EliminateNestedLocks || 2068 oldbox->as_BoxLock()->is_simple_lock_region(NULL, obj)) { 2069 // Box is used only in one lock region. Mark this box as eliminated. 2070 _igvn.hash_delete(oldbox); 2071 oldbox->as_BoxLock()->set_eliminated(); // This changes box's hash value 2072 _igvn.hash_insert(oldbox); 2073 2074 for (uint i = 0; i < oldbox->outcnt(); i++) { 2075 Node* u = oldbox->raw_out(i); 2076 if (u->is_AbstractLock() && !u->as_AbstractLock()->is_non_esc_obj()) { 2077 AbstractLockNode* alock = u->as_AbstractLock(); 2078 // Check lock's box since box could be referenced by Lock's debug info. 2079 if (alock->box_node() == oldbox) { 2080 // Mark eliminated all related locks and unlocks. 2081 #ifdef ASSERT 2082 alock->log_lock_optimization(C, "eliminate_lock_set_non_esc4"); 2083 #endif 2084 alock->set_non_esc_obj(); 2085 } 2086 } 2087 } 2088 return; 2089 } 2090 2091 // Create new "eliminated" BoxLock node and use it in monitor debug info 2092 // instead of oldbox for the same object. 2093 BoxLockNode* newbox = oldbox->clone()->as_BoxLock(); 2094 2095 // Note: BoxLock node is marked eliminated only here and it is used 2096 // to indicate that all associated lock and unlock nodes are marked 2097 // for elimination. 2098 newbox->set_eliminated(); 2099 transform_later(newbox); 2100 2101 // Replace old box node with new box for all users of the same object. 2102 for (uint i = 0; i < oldbox->outcnt();) { 2103 bool next_edge = true; 2104 2105 Node* u = oldbox->raw_out(i); 2106 if (u->is_AbstractLock()) { 2107 AbstractLockNode* alock = u->as_AbstractLock(); 2108 if (alock->box_node() == oldbox && alock->obj_node()->eqv_uncast(obj)) { 2109 // Replace Box and mark eliminated all related locks and unlocks. 2110 #ifdef ASSERT 2111 alock->log_lock_optimization(C, "eliminate_lock_set_non_esc5"); 2112 #endif 2113 alock->set_non_esc_obj(); 2114 _igvn.rehash_node_delayed(alock); 2115 alock->set_box_node(newbox); 2116 next_edge = false; 2117 } 2118 } 2119 if (u->is_FastLock() && u->as_FastLock()->obj_node()->eqv_uncast(obj)) { 2120 FastLockNode* flock = u->as_FastLock(); 2121 assert(flock->box_node() == oldbox, "sanity"); 2122 _igvn.rehash_node_delayed(flock); 2123 flock->set_box_node(newbox); 2124 next_edge = false; 2125 } 2126 2127 // Replace old box in monitor debug info. 2128 if (u->is_SafePoint() && u->as_SafePoint()->jvms()) { 2129 SafePointNode* sfn = u->as_SafePoint(); 2130 JVMState* youngest_jvms = sfn->jvms(); 2131 int max_depth = youngest_jvms->depth(); 2132 for (int depth = 1; depth <= max_depth; depth++) { 2133 JVMState* jvms = youngest_jvms->of_depth(depth); 2134 int num_mon = jvms->nof_monitors(); 2135 // Loop over monitors 2136 for (int idx = 0; idx < num_mon; idx++) { 2137 Node* obj_node = sfn->monitor_obj(jvms, idx); 2138 Node* box_node = sfn->monitor_box(jvms, idx); 2139 if (box_node == oldbox && obj_node->eqv_uncast(obj)) { 2140 int j = jvms->monitor_box_offset(idx); 2141 _igvn.replace_input_of(u, j, newbox); 2142 next_edge = false; 2143 } 2144 } 2145 } 2146 } 2147 if (next_edge) i++; 2148 } 2149 } 2150 2151 //-----------------------mark_eliminated_locking_nodes----------------------- 2152 void PhaseMacroExpand::mark_eliminated_locking_nodes(AbstractLockNode *alock) { 2153 if (EliminateNestedLocks) { 2154 if (alock->is_nested()) { 2155 assert(alock->box_node()->as_BoxLock()->is_eliminated(), "sanity"); 2156 return; 2157 } else if (!alock->is_non_esc_obj()) { // Not eliminated or coarsened 2158 // Only Lock node has JVMState needed here. 2159 // Not that preceding claim is documented anywhere else. 2160 if (alock->jvms() != NULL) { 2161 if (alock->as_Lock()->is_nested_lock_region()) { 2162 // Mark eliminated related nested locks and unlocks. 2163 Node* obj = alock->obj_node(); 2164 BoxLockNode* box_node = alock->box_node()->as_BoxLock(); 2165 assert(!box_node->is_eliminated(), "should not be marked yet"); 2166 // Note: BoxLock node is marked eliminated only here 2167 // and it is used to indicate that all associated lock 2168 // and unlock nodes are marked for elimination. 2169 box_node->set_eliminated(); // Box's hash is always NO_HASH here 2170 for (uint i = 0; i < box_node->outcnt(); i++) { 2171 Node* u = box_node->raw_out(i); 2172 if (u->is_AbstractLock()) { 2173 alock = u->as_AbstractLock(); 2174 if (alock->box_node() == box_node) { 2175 // Verify that this Box is referenced only by related locks. 2176 assert(alock->obj_node()->eqv_uncast(obj), ""); 2177 // Mark all related locks and unlocks. 2178 #ifdef ASSERT 2179 alock->log_lock_optimization(C, "eliminate_lock_set_nested"); 2180 #endif 2181 alock->set_nested(); 2182 } 2183 } 2184 } 2185 } else { 2186 #ifdef ASSERT 2187 alock->log_lock_optimization(C, "eliminate_lock_NOT_nested_lock_region"); 2188 if (C->log() != NULL) 2189 alock->as_Lock()->is_nested_lock_region(C); // rerun for debugging output 2190 #endif 2191 } 2192 } 2193 return; 2194 } 2195 // Process locks for non escaping object 2196 assert(alock->is_non_esc_obj(), ""); 2197 } // EliminateNestedLocks 2198 2199 if (alock->is_non_esc_obj()) { // Lock is used for non escaping object 2200 // Look for all locks of this object and mark them and 2201 // corresponding BoxLock nodes as eliminated. 2202 Node* obj = alock->obj_node(); 2203 for (uint j = 0; j < obj->outcnt(); j++) { 2204 Node* o = obj->raw_out(j); 2205 if (o->is_AbstractLock() && 2206 o->as_AbstractLock()->obj_node()->eqv_uncast(obj)) { 2207 alock = o->as_AbstractLock(); 2208 Node* box = alock->box_node(); 2209 // Replace old box node with new eliminated box for all users 2210 // of the same object and mark related locks as eliminated. 2211 mark_eliminated_box(box, obj); 2212 } 2213 } 2214 } 2215 } 2216 2217 // we have determined that this lock/unlock can be eliminated, we simply 2218 // eliminate the node without expanding it. 2219 // 2220 // Note: The membar's associated with the lock/unlock are currently not 2221 // eliminated. This should be investigated as a future enhancement. 2222 // 2223 bool PhaseMacroExpand::eliminate_locking_node(AbstractLockNode *alock) { 2224 2225 if (!alock->is_eliminated()) { 2226 return false; 2227 } 2228 #ifdef ASSERT 2229 if (!alock->is_coarsened()) { 2230 // Check that new "eliminated" BoxLock node is created. 2231 BoxLockNode* oldbox = alock->box_node()->as_BoxLock(); 2232 assert(oldbox->is_eliminated(), "should be done already"); 2233 } 2234 #endif 2235 2236 alock->log_lock_optimization(C, "eliminate_lock"); 2237 2238 #ifndef PRODUCT 2239 if (PrintEliminateLocks) { 2240 if (alock->is_Lock()) { 2241 tty->print_cr("++++ Eliminated: %d Lock", alock->_idx); 2242 } else { 2243 tty->print_cr("++++ Eliminated: %d Unlock", alock->_idx); 2244 } 2245 } 2246 #endif 2247 2248 Node* mem = alock->in(TypeFunc::Memory); 2249 Node* ctrl = alock->in(TypeFunc::Control); 2250 2251 extract_call_projections(alock); 2252 // There are 2 projections from the lock. The lock node will 2253 // be deleted when its last use is subsumed below. 2254 assert(alock->outcnt() == 2 && 2255 _fallthroughproj != NULL && 2256 _memproj_fallthrough != NULL, 2257 "Unexpected projections from Lock/Unlock"); 2258 2259 Node* fallthroughproj = _fallthroughproj; 2260 Node* memproj_fallthrough = _memproj_fallthrough; 2261 2262 // The memory projection from a lock/unlock is RawMem 2263 // The input to a Lock is merged memory, so extract its RawMem input 2264 // (unless the MergeMem has been optimized away.) 2265 if (alock->is_Lock()) { 2266 // Seach for MemBarAcquireLock node and delete it also. 2267 MemBarNode* membar = fallthroughproj->unique_ctrl_out()->as_MemBar(); 2268 assert(membar != NULL && membar->Opcode() == Op_MemBarAcquireLock, ""); 2269 Node* ctrlproj = membar->proj_out(TypeFunc::Control); 2270 Node* memproj = membar->proj_out(TypeFunc::Memory); 2271 _igvn.replace_node(ctrlproj, fallthroughproj); 2272 _igvn.replace_node(memproj, memproj_fallthrough); 2273 2274 // Delete FastLock node also if this Lock node is unique user 2275 // (a loop peeling may clone a Lock node). 2276 Node* flock = alock->as_Lock()->fastlock_node(); 2277 if (flock->outcnt() == 1) { 2278 assert(flock->unique_out() == alock, "sanity"); 2279 _igvn.replace_node(flock, top()); 2280 } 2281 } 2282 2283 // Seach for MemBarReleaseLock node and delete it also. 2284 if (alock->is_Unlock() && ctrl != NULL && ctrl->is_Proj() && 2285 ctrl->in(0)->is_MemBar()) { 2286 MemBarNode* membar = ctrl->in(0)->as_MemBar(); 2287 assert(membar->Opcode() == Op_MemBarReleaseLock && 2288 mem->is_Proj() && membar == mem->in(0), ""); 2289 _igvn.replace_node(fallthroughproj, ctrl); 2290 _igvn.replace_node(memproj_fallthrough, mem); 2291 fallthroughproj = ctrl; 2292 memproj_fallthrough = mem; 2293 ctrl = membar->in(TypeFunc::Control); 2294 mem = membar->in(TypeFunc::Memory); 2295 } 2296 2297 _igvn.replace_node(fallthroughproj, ctrl); 2298 _igvn.replace_node(memproj_fallthrough, mem); 2299 return true; 2300 } 2301 2302 2303 //------------------------------expand_lock_node---------------------- 2304 void PhaseMacroExpand::expand_lock_node(LockNode *lock) { 2305 2306 Node* ctrl = lock->in(TypeFunc::Control); 2307 Node* mem = lock->in(TypeFunc::Memory); 2308 Node* obj = lock->obj_node(); 2309 Node* box = lock->box_node(); 2310 Node* flock = lock->fastlock_node(); 2311 2312 assert(!box->as_BoxLock()->is_eliminated(), "sanity"); 2313 2314 // Make the merge point 2315 Node *region; 2316 Node *mem_phi; 2317 Node *slow_path; 2318 2319 if (UseOptoBiasInlining) { 2320 /* 2321 * See the full description in MacroAssembler::biased_locking_enter(). 2322 * 2323 * if( (mark_word & biased_lock_mask) == biased_lock_pattern ) { 2324 * // The object is biased. 2325 * proto_node = klass->prototype_header; 2326 * o_node = thread | proto_node; 2327 * x_node = o_node ^ mark_word; 2328 * if( (x_node & ~age_mask) == 0 ) { // Biased to the current thread ? 2329 * // Done. 2330 * } else { 2331 * if( (x_node & biased_lock_mask) != 0 ) { 2332 * // The klass's prototype header is no longer biased. 2333 * cas(&mark_word, mark_word, proto_node) 2334 * goto cas_lock; 2335 * } else { 2336 * // The klass's prototype header is still biased. 2337 * if( (x_node & epoch_mask) != 0 ) { // Expired epoch? 2338 * old = mark_word; 2339 * new = o_node; 2340 * } else { 2341 * // Different thread or anonymous biased. 2342 * old = mark_word & (epoch_mask | age_mask | biased_lock_mask); 2343 * new = thread | old; 2344 * } 2345 * // Try to rebias. 2346 * if( cas(&mark_word, old, new) == 0 ) { 2347 * // Done. 2348 * } else { 2349 * goto slow_path; // Failed. 2350 * } 2351 * } 2352 * } 2353 * } else { 2354 * // The object is not biased. 2355 * cas_lock: 2356 * if( FastLock(obj) == 0 ) { 2357 * // Done. 2358 * } else { 2359 * slow_path: 2360 * OptoRuntime::complete_monitor_locking_Java(obj); 2361 * } 2362 * } 2363 */ 2364 2365 region = new RegionNode(5); 2366 // create a Phi for the memory state 2367 mem_phi = new PhiNode( region, Type::MEMORY, TypeRawPtr::BOTTOM); 2368 2369 Node* fast_lock_region = new RegionNode(3); 2370 Node* fast_lock_mem_phi = new PhiNode( fast_lock_region, Type::MEMORY, TypeRawPtr::BOTTOM); 2371 2372 // First, check mark word for the biased lock pattern. 2373 Node* mark_node = make_load(ctrl, mem, obj, oopDesc::mark_offset_in_bytes(), TypeX_X, TypeX_X->basic_type()); 2374 2375 // Get fast path - mark word has the biased lock pattern. 2376 ctrl = opt_bits_test(ctrl, fast_lock_region, 1, mark_node, 2377 markOopDesc::biased_lock_mask_in_place, 2378 markOopDesc::biased_lock_pattern, true); 2379 // fast_lock_region->in(1) is set to slow path. 2380 fast_lock_mem_phi->init_req(1, mem); 2381 2382 // Now check that the lock is biased to the current thread and has 2383 // the same epoch and bias as Klass::_prototype_header. 2384 2385 // Special-case a fresh allocation to avoid building nodes: 2386 Node* klass_node = AllocateNode::Ideal_klass(obj, &_igvn); 2387 if (klass_node == NULL) { 2388 Node* k_adr = basic_plus_adr(obj, oopDesc::klass_offset_in_bytes()); 2389 klass_node = transform_later(LoadKlassNode::make(_igvn, NULL, mem, k_adr, _igvn.type(k_adr)->is_ptr())); 2390 #ifdef _LP64 2391 if (UseCompressedClassPointers && klass_node->is_DecodeNKlass()) { 2392 assert(klass_node->in(1)->Opcode() == Op_LoadNKlass, "sanity"); 2393 klass_node->in(1)->init_req(0, ctrl); 2394 } else 2395 #endif 2396 klass_node->init_req(0, ctrl); 2397 } 2398 Node *proto_node = make_load(ctrl, mem, klass_node, in_bytes(Klass::prototype_header_offset()), TypeX_X, TypeX_X->basic_type()); 2399 2400 Node* thread = transform_later(new ThreadLocalNode()); 2401 Node* cast_thread = transform_later(new CastP2XNode(ctrl, thread)); 2402 Node* o_node = transform_later(new OrXNode(cast_thread, proto_node)); 2403 Node* x_node = transform_later(new XorXNode(o_node, mark_node)); 2404 2405 // Get slow path - mark word does NOT match the value. 2406 Node* not_biased_ctrl = opt_bits_test(ctrl, region, 3, x_node, 2407 (~markOopDesc::age_mask_in_place), 0); 2408 // region->in(3) is set to fast path - the object is biased to the current thread. 2409 mem_phi->init_req(3, mem); 2410 2411 2412 // Mark word does NOT match the value (thread | Klass::_prototype_header). 2413 2414 2415 // First, check biased pattern. 2416 // Get fast path - _prototype_header has the same biased lock pattern. 2417 ctrl = opt_bits_test(not_biased_ctrl, fast_lock_region, 2, x_node, 2418 markOopDesc::biased_lock_mask_in_place, 0, true); 2419 2420 not_biased_ctrl = fast_lock_region->in(2); // Slow path 2421 // fast_lock_region->in(2) - the prototype header is no longer biased 2422 // and we have to revoke the bias on this object. 2423 // We are going to try to reset the mark of this object to the prototype 2424 // value and fall through to the CAS-based locking scheme. 2425 Node* adr = basic_plus_adr(obj, oopDesc::mark_offset_in_bytes()); 2426 Node* cas = new StoreXConditionalNode(not_biased_ctrl, mem, adr, 2427 proto_node, mark_node); 2428 transform_later(cas); 2429 Node* proj = transform_later(new SCMemProjNode(cas)); 2430 fast_lock_mem_phi->init_req(2, proj); 2431 2432 2433 // Second, check epoch bits. 2434 Node* rebiased_region = new RegionNode(3); 2435 Node* old_phi = new PhiNode( rebiased_region, TypeX_X); 2436 Node* new_phi = new PhiNode( rebiased_region, TypeX_X); 2437 2438 // Get slow path - mark word does NOT match epoch bits. 2439 Node* epoch_ctrl = opt_bits_test(ctrl, rebiased_region, 1, x_node, 2440 markOopDesc::epoch_mask_in_place, 0); 2441 // The epoch of the current bias is not valid, attempt to rebias the object 2442 // toward the current thread. 2443 rebiased_region->init_req(2, epoch_ctrl); 2444 old_phi->init_req(2, mark_node); 2445 new_phi->init_req(2, o_node); 2446 2447 // rebiased_region->in(1) is set to fast path. 2448 // The epoch of the current bias is still valid but we know 2449 // nothing about the owner; it might be set or it might be clear. 2450 Node* cmask = MakeConX(markOopDesc::biased_lock_mask_in_place | 2451 markOopDesc::age_mask_in_place | 2452 markOopDesc::epoch_mask_in_place); 2453 Node* old = transform_later(new AndXNode(mark_node, cmask)); 2454 cast_thread = transform_later(new CastP2XNode(ctrl, thread)); 2455 Node* new_mark = transform_later(new OrXNode(cast_thread, old)); 2456 old_phi->init_req(1, old); 2457 new_phi->init_req(1, new_mark); 2458 2459 transform_later(rebiased_region); 2460 transform_later(old_phi); 2461 transform_later(new_phi); 2462 2463 // Try to acquire the bias of the object using an atomic operation. 2464 // If this fails we will go in to the runtime to revoke the object's bias. 2465 cas = new StoreXConditionalNode(rebiased_region, mem, adr, new_phi, old_phi); 2466 transform_later(cas); 2467 proj = transform_later(new SCMemProjNode(cas)); 2468 2469 // Get slow path - Failed to CAS. 2470 not_biased_ctrl = opt_bits_test(rebiased_region, region, 4, cas, 0, 0); 2471 mem_phi->init_req(4, proj); 2472 // region->in(4) is set to fast path - the object is rebiased to the current thread. 2473 2474 // Failed to CAS. 2475 slow_path = new RegionNode(3); 2476 Node *slow_mem = new PhiNode( slow_path, Type::MEMORY, TypeRawPtr::BOTTOM); 2477 2478 slow_path->init_req(1, not_biased_ctrl); // Capture slow-control 2479 slow_mem->init_req(1, proj); 2480 2481 // Call CAS-based locking scheme (FastLock node). 2482 2483 transform_later(fast_lock_region); 2484 transform_later(fast_lock_mem_phi); 2485 2486 // Get slow path - FastLock failed to lock the object. 2487 ctrl = opt_bits_test(fast_lock_region, region, 2, flock, 0, 0); 2488 mem_phi->init_req(2, fast_lock_mem_phi); 2489 // region->in(2) is set to fast path - the object is locked to the current thread. 2490 2491 slow_path->init_req(2, ctrl); // Capture slow-control 2492 slow_mem->init_req(2, fast_lock_mem_phi); 2493 2494 transform_later(slow_path); 2495 transform_later(slow_mem); 2496 // Reset lock's memory edge. 2497 lock->set_req(TypeFunc::Memory, slow_mem); 2498 2499 } else { 2500 region = new RegionNode(3); 2501 // create a Phi for the memory state 2502 mem_phi = new PhiNode( region, Type::MEMORY, TypeRawPtr::BOTTOM); 2503 2504 // Optimize test; set region slot 2 2505 slow_path = opt_bits_test(ctrl, region, 2, flock, 0, 0); 2506 mem_phi->init_req(2, mem); 2507 } 2508 2509 // Make slow path call 2510 CallNode *call = make_slow_call((CallNode *) lock, OptoRuntime::complete_monitor_enter_Type(), 2511 OptoRuntime::complete_monitor_locking_Java(), NULL, slow_path, 2512 obj, box, NULL); 2513 2514 extract_call_projections(call); 2515 2516 // Slow path can only throw asynchronous exceptions, which are always 2517 // de-opted. So the compiler thinks the slow-call can never throw an 2518 // exception. If it DOES throw an exception we would need the debug 2519 // info removed first (since if it throws there is no monitor). 2520 assert ( _ioproj_fallthrough == NULL && _ioproj_catchall == NULL && 2521 _memproj_catchall == NULL && _catchallcatchproj == NULL, "Unexpected projection from Lock"); 2522 2523 // Capture slow path 2524 // disconnect fall-through projection from call and create a new one 2525 // hook up users of fall-through projection to region 2526 Node *slow_ctrl = _fallthroughproj->clone(); 2527 transform_later(slow_ctrl); 2528 _igvn.hash_delete(_fallthroughproj); 2529 _fallthroughproj->disconnect_inputs(NULL, C); 2530 region->init_req(1, slow_ctrl); 2531 // region inputs are now complete 2532 transform_later(region); 2533 _igvn.replace_node(_fallthroughproj, region); 2534 2535 Node *memproj = transform_later(new ProjNode(call, TypeFunc::Memory)); 2536 mem_phi->init_req(1, memproj ); 2537 transform_later(mem_phi); 2538 _igvn.replace_node(_memproj_fallthrough, mem_phi); 2539 } 2540 2541 //------------------------------expand_unlock_node---------------------- 2542 void PhaseMacroExpand::expand_unlock_node(UnlockNode *unlock) { 2543 2544 Node* ctrl = unlock->in(TypeFunc::Control); 2545 Node* mem = unlock->in(TypeFunc::Memory); 2546 Node* obj = unlock->obj_node(); 2547 Node* box = unlock->box_node(); 2548 2549 assert(!box->as_BoxLock()->is_eliminated(), "sanity"); 2550 2551 // No need for a null check on unlock 2552 2553 // Make the merge point 2554 Node *region; 2555 Node *mem_phi; 2556 2557 if (UseOptoBiasInlining) { 2558 // Check for biased locking unlock case, which is a no-op. 2559 // See the full description in MacroAssembler::biased_locking_exit(). 2560 region = new RegionNode(4); 2561 // create a Phi for the memory state 2562 mem_phi = new PhiNode( region, Type::MEMORY, TypeRawPtr::BOTTOM); 2563 mem_phi->init_req(3, mem); 2564 2565 Node* mark_node = make_load(ctrl, mem, obj, oopDesc::mark_offset_in_bytes(), TypeX_X, TypeX_X->basic_type()); 2566 ctrl = opt_bits_test(ctrl, region, 3, mark_node, 2567 markOopDesc::biased_lock_mask_in_place, 2568 markOopDesc::biased_lock_pattern); 2569 } else { 2570 region = new RegionNode(3); 2571 // create a Phi for the memory state 2572 mem_phi = new PhiNode( region, Type::MEMORY, TypeRawPtr::BOTTOM); 2573 } 2574 2575 FastUnlockNode *funlock = new FastUnlockNode( ctrl, obj, box ); 2576 funlock = transform_later( funlock )->as_FastUnlock(); 2577 // Optimize test; set region slot 2 2578 Node *slow_path = opt_bits_test(ctrl, region, 2, funlock, 0, 0); 2579 Node *thread = transform_later(new ThreadLocalNode()); 2580 2581 CallNode *call = make_slow_call((CallNode *) unlock, OptoRuntime::complete_monitor_exit_Type(), 2582 CAST_FROM_FN_PTR(address, SharedRuntime::complete_monitor_unlocking_C), 2583 "complete_monitor_unlocking_C", slow_path, obj, box, thread); 2584 2585 extract_call_projections(call); 2586 2587 assert ( _ioproj_fallthrough == NULL && _ioproj_catchall == NULL && 2588 _memproj_catchall == NULL && _catchallcatchproj == NULL, "Unexpected projection from Lock"); 2589 2590 // No exceptions for unlocking 2591 // Capture slow path 2592 // disconnect fall-through projection from call and create a new one 2593 // hook up users of fall-through projection to region 2594 Node *slow_ctrl = _fallthroughproj->clone(); 2595 transform_later(slow_ctrl); 2596 _igvn.hash_delete(_fallthroughproj); 2597 _fallthroughproj->disconnect_inputs(NULL, C); 2598 region->init_req(1, slow_ctrl); 2599 // region inputs are now complete 2600 transform_later(region); 2601 _igvn.replace_node(_fallthroughproj, region); 2602 2603 Node *memproj = transform_later(new ProjNode(call, TypeFunc::Memory) ); 2604 mem_phi->init_req(1, memproj ); 2605 mem_phi->init_req(2, mem); 2606 transform_later(mem_phi); 2607 _igvn.replace_node(_memproj_fallthrough, mem_phi); 2608 } 2609 2610 //---------------------------eliminate_macro_nodes---------------------- 2611 // Eliminate scalar replaced allocations and associated locks. 2612 void PhaseMacroExpand::eliminate_macro_nodes() { 2613 if (C->macro_count() == 0) 2614 return; 2615 2616 // First, attempt to eliminate locks 2617 int cnt = C->macro_count(); 2618 for (int i=0; i < cnt; i++) { 2619 Node *n = C->macro_node(i); 2620 if (n->is_AbstractLock()) { // Lock and Unlock nodes 2621 // Before elimination mark all associated (same box and obj) 2622 // lock and unlock nodes. 2623 mark_eliminated_locking_nodes(n->as_AbstractLock()); 2624 } 2625 } 2626 bool progress = true; 2627 while (progress) { 2628 progress = false; 2629 for (int i = C->macro_count(); i > 0; i--) { 2630 Node * n = C->macro_node(i-1); 2631 bool success = false; 2632 debug_only(int old_macro_count = C->macro_count();); 2633 if (n->is_AbstractLock()) { 2634 success = eliminate_locking_node(n->as_AbstractLock()); 2635 } 2636 assert(success == (C->macro_count() < old_macro_count), "elimination reduces macro count"); 2637 progress = progress || success; 2638 } 2639 } 2640 // Next, attempt to eliminate allocations 2641 _has_locks = false; 2642 progress = true; 2643 while (progress) { 2644 progress = false; 2645 for (int i = C->macro_count(); i > 0; i--) { 2646 Node * n = C->macro_node(i-1); 2647 bool success = false; 2648 debug_only(int old_macro_count = C->macro_count();); 2649 switch (n->class_id()) { 2650 case Node::Class_Allocate: 2651 case Node::Class_AllocateArray: 2652 success = eliminate_allocate_node(n->as_Allocate()); 2653 break; 2654 case Node::Class_CallStaticJava: 2655 success = eliminate_boxing_node(n->as_CallStaticJava()); 2656 break; 2657 case Node::Class_Lock: 2658 case Node::Class_Unlock: 2659 assert(!n->as_AbstractLock()->is_eliminated(), "sanity"); 2660 _has_locks = true; 2661 break; 2662 case Node::Class_ArrayCopy: 2663 break; 2664 case Node::Class_OuterStripMinedLoop: 2665 break; 2666 default: 2667 assert(n->Opcode() == Op_LoopLimit || 2668 n->Opcode() == Op_Opaque1 || 2669 n->Opcode() == Op_Opaque2 || 2670 n->Opcode() == Op_Opaque3 || 2671 n->Opcode() == Op_Opaque4, "unknown node type in macro list"); 2672 } 2673 assert(success == (C->macro_count() < old_macro_count), "elimination reduces macro count"); 2674 progress = progress || success; 2675 } 2676 } 2677 } 2678 2679 //------------------------------expand_macro_nodes---------------------- 2680 // Returns true if a failure occurred. 2681 bool PhaseMacroExpand::expand_macro_nodes() { 2682 // Last attempt to eliminate macro nodes. 2683 eliminate_macro_nodes(); 2684 2685 // Make sure expansion will not cause node limit to be exceeded. 2686 // Worst case is a macro node gets expanded into about 200 nodes. 2687 // Allow 50% more for optimization. 2688 if (C->check_node_count(C->macro_count() * 300, "out of nodes before macro expansion" ) ) 2689 return true; 2690 2691 // Eliminate Opaque and LoopLimit nodes. Do it after all loop optimizations. 2692 bool progress = true; 2693 while (progress) { 2694 progress = false; 2695 for (int i = C->macro_count(); i > 0; i--) { 2696 Node * n = C->macro_node(i-1); 2697 bool success = false; 2698 debug_only(int old_macro_count = C->macro_count();); 2699 if (n->Opcode() == Op_LoopLimit) { 2700 // Remove it from macro list and put on IGVN worklist to optimize. 2701 C->remove_macro_node(n); 2702 _igvn._worklist.push(n); 2703 success = true; 2704 } else if (n->Opcode() == Op_CallStaticJava) { 2705 // Remove it from macro list and put on IGVN worklist to optimize. 2706 C->remove_macro_node(n); 2707 _igvn._worklist.push(n); 2708 success = true; 2709 } else if (n->Opcode() == Op_Opaque1 || n->Opcode() == Op_Opaque2) { 2710 _igvn.replace_node(n, n->in(1)); 2711 success = true; 2712 #if INCLUDE_RTM_OPT 2713 } else if ((n->Opcode() == Op_Opaque3) && ((Opaque3Node*)n)->rtm_opt()) { 2714 assert(C->profile_rtm(), "should be used only in rtm deoptimization code"); 2715 assert((n->outcnt() == 1) && n->unique_out()->is_Cmp(), ""); 2716 Node* cmp = n->unique_out(); 2717 #ifdef ASSERT 2718 // Validate graph. 2719 assert((cmp->outcnt() == 1) && cmp->unique_out()->is_Bool(), ""); 2720 BoolNode* bol = cmp->unique_out()->as_Bool(); 2721 assert((bol->outcnt() == 1) && bol->unique_out()->is_If() && 2722 (bol->_test._test == BoolTest::ne), ""); 2723 IfNode* ifn = bol->unique_out()->as_If(); 2724 assert((ifn->outcnt() == 2) && 2725 ifn->proj_out(1)->is_uncommon_trap_proj(Deoptimization::Reason_rtm_state_change) != NULL, ""); 2726 #endif 2727 Node* repl = n->in(1); 2728 if (!_has_locks) { 2729 // Remove RTM state check if there are no locks in the code. 2730 // Replace input to compare the same value. 2731 repl = (cmp->in(1) == n) ? cmp->in(2) : cmp->in(1); 2732 } 2733 _igvn.replace_node(n, repl); 2734 success = true; 2735 #endif 2736 } else if (n->Opcode() == Op_Opaque4) { 2737 _igvn.replace_node(n, n->in(2)); 2738 success = true; 2739 } else if (n->Opcode() == Op_OuterStripMinedLoop) { 2740 n->as_OuterStripMinedLoop()->adjust_strip_mined_loop(&_igvn); 2741 C->remove_macro_node(n); 2742 success = true; 2743 } 2744 assert(success == (C->macro_count() < old_macro_count), "elimination reduces macro count"); 2745 progress = progress || success; 2746 } 2747 } 2748 2749 // expand arraycopy "macro" nodes first 2750 // For ReduceBulkZeroing, we must first process all arraycopy nodes 2751 // before the allocate nodes are expanded. 2752 int macro_idx = C->macro_count() - 1; 2753 while (macro_idx >= 0) { 2754 Node * n = C->macro_node(macro_idx); 2755 assert(n->is_macro(), "only macro nodes expected here"); 2756 if (_igvn.type(n) == Type::TOP || n->in(0)->is_top() ) { 2757 // node is unreachable, so don't try to expand it 2758 C->remove_macro_node(n); 2759 } else if (n->is_ArrayCopy()){ 2760 int macro_count = C->macro_count(); 2761 expand_arraycopy_node(n->as_ArrayCopy()); 2762 assert(C->macro_count() < macro_count, "must have deleted a node from macro list"); 2763 } 2764 if (C->failing()) return true; 2765 macro_idx --; 2766 } 2767 2768 // expand "macro" nodes 2769 // nodes are removed from the macro list as they are processed 2770 while (C->macro_count() > 0) { 2771 int macro_count = C->macro_count(); 2772 Node * n = C->macro_node(macro_count-1); 2773 assert(n->is_macro(), "only macro nodes expected here"); 2774 if (_igvn.type(n) == Type::TOP || n->in(0)->is_top() ) { 2775 // node is unreachable, so don't try to expand it 2776 C->remove_macro_node(n); 2777 continue; 2778 } 2779 switch (n->class_id()) { 2780 case Node::Class_Allocate: 2781 expand_allocate(n->as_Allocate()); 2782 break; 2783 case Node::Class_AllocateArray: 2784 expand_allocate_array(n->as_AllocateArray()); 2785 break; 2786 case Node::Class_Lock: 2787 expand_lock_node(n->as_Lock()); 2788 break; 2789 case Node::Class_Unlock: 2790 expand_unlock_node(n->as_Unlock()); 2791 break; 2792 default: 2793 assert(false, "unknown node type in macro list"); 2794 } 2795 assert(C->macro_count() < macro_count, "must have deleted a node from macro list"); 2796 if (C->failing()) return true; 2797 } 2798 2799 _igvn.set_delay_transform(false); 2800 _igvn.optimize(); 2801 if (C->failing()) return true; 2802 return false; 2803 }