1 /* 2 * Copyright 2001-2009 Sun Microsystems, Inc. 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 Sun Microsystems, Inc., 4150 Network Circle, Santa Clara, 20 * CA 95054 USA or visit www.sun.com if you need additional information or 21 * have any questions. 22 * 23 */ 24 25 #include "incls/_precompiled.incl" 26 #include "incls/_graphKit.cpp.incl" 27 28 //----------------------------GraphKit----------------------------------------- 29 // Main utility constructor. 30 GraphKit::GraphKit(JVMState* jvms) 31 : Phase(Phase::Parser), 32 _env(C->env()), 33 _gvn(*C->initial_gvn()) 34 { 35 _exceptions = jvms->map()->next_exception(); 36 if (_exceptions != NULL) jvms->map()->set_next_exception(NULL); 37 set_jvms(jvms); 38 } 39 40 // Private constructor for parser. 41 GraphKit::GraphKit() 42 : Phase(Phase::Parser), 43 _env(C->env()), 44 _gvn(*C->initial_gvn()) 45 { 46 _exceptions = NULL; 47 set_map(NULL); 48 debug_only(_sp = -99); 49 debug_only(set_bci(-99)); 50 } 51 52 53 54 //---------------------------clean_stack--------------------------------------- 55 // Clear away rubbish from the stack area of the JVM state. 56 // This destroys any arguments that may be waiting on the stack. 57 void GraphKit::clean_stack(int from_sp) { 58 SafePointNode* map = this->map(); 59 JVMState* jvms = this->jvms(); 60 int stk_size = jvms->stk_size(); 61 int stkoff = jvms->stkoff(); 62 Node* top = this->top(); 63 for (int i = from_sp; i < stk_size; i++) { 64 if (map->in(stkoff + i) != top) { 65 map->set_req(stkoff + i, top); 66 } 67 } 68 } 69 70 71 //--------------------------------sync_jvms----------------------------------- 72 // Make sure our current jvms agrees with our parse state. 73 JVMState* GraphKit::sync_jvms() const { 74 JVMState* jvms = this->jvms(); 75 jvms->set_bci(bci()); // Record the new bci in the JVMState 76 jvms->set_sp(sp()); // Record the new sp in the JVMState 77 assert(jvms_in_sync(), "jvms is now in sync"); 78 return jvms; 79 } 80 81 #ifdef ASSERT 82 bool GraphKit::jvms_in_sync() const { 83 Parse* parse = is_Parse(); 84 if (parse == NULL) { 85 if (bci() != jvms()->bci()) return false; 86 if (sp() != (int)jvms()->sp()) return false; 87 return true; 88 } 89 if (jvms()->method() != parse->method()) return false; 90 if (jvms()->bci() != parse->bci()) return false; 91 int jvms_sp = jvms()->sp(); 92 if (jvms_sp != parse->sp()) return false; 93 int jvms_depth = jvms()->depth(); 94 if (jvms_depth != parse->depth()) return false; 95 return true; 96 } 97 98 // Local helper checks for special internal merge points 99 // used to accumulate and merge exception states. 100 // They are marked by the region's in(0) edge being the map itself. 101 // Such merge points must never "escape" into the parser at large, 102 // until they have been handed to gvn.transform. 103 static bool is_hidden_merge(Node* reg) { 104 if (reg == NULL) return false; 105 if (reg->is_Phi()) { 106 reg = reg->in(0); 107 if (reg == NULL) return false; 108 } 109 return reg->is_Region() && reg->in(0) != NULL && reg->in(0)->is_Root(); 110 } 111 112 void GraphKit::verify_map() const { 113 if (map() == NULL) return; // null map is OK 114 assert(map()->req() <= jvms()->endoff(), "no extra garbage on map"); 115 assert(!map()->has_exceptions(), "call add_exception_states_from 1st"); 116 assert(!is_hidden_merge(control()), "call use_exception_state, not set_map"); 117 } 118 119 void GraphKit::verify_exception_state(SafePointNode* ex_map) { 120 assert(ex_map->next_exception() == NULL, "not already part of a chain"); 121 assert(has_saved_ex_oop(ex_map), "every exception state has an ex_oop"); 122 } 123 #endif 124 125 //---------------------------stop_and_kill_map--------------------------------- 126 // Set _map to NULL, signalling a stop to further bytecode execution. 127 // First smash the current map's control to a constant, to mark it dead. 128 void GraphKit::stop_and_kill_map() { 129 SafePointNode* dead_map = stop(); 130 if (dead_map != NULL) { 131 dead_map->disconnect_inputs(NULL); // Mark the map as killed. 132 assert(dead_map->is_killed(), "must be so marked"); 133 } 134 } 135 136 137 //--------------------------------stopped-------------------------------------- 138 // Tell if _map is NULL, or control is top. 139 bool GraphKit::stopped() { 140 if (map() == NULL) return true; 141 else if (control() == top()) return true; 142 else return false; 143 } 144 145 146 //-----------------------------has_ex_handler---------------------------------- 147 // Tell if this method or any caller method has exception handlers. 148 bool GraphKit::has_ex_handler() { 149 for (JVMState* jvmsp = jvms(); jvmsp != NULL; jvmsp = jvmsp->caller()) { 150 if (jvmsp->has_method() && jvmsp->method()->has_exception_handlers()) { 151 return true; 152 } 153 } 154 return false; 155 } 156 157 //------------------------------save_ex_oop------------------------------------ 158 // Save an exception without blowing stack contents or other JVM state. 159 void GraphKit::set_saved_ex_oop(SafePointNode* ex_map, Node* ex_oop) { 160 assert(!has_saved_ex_oop(ex_map), "clear ex-oop before setting again"); 161 ex_map->add_req(ex_oop); 162 debug_only(verify_exception_state(ex_map)); 163 } 164 165 inline static Node* common_saved_ex_oop(SafePointNode* ex_map, bool clear_it) { 166 assert(GraphKit::has_saved_ex_oop(ex_map), "ex_oop must be there"); 167 Node* ex_oop = ex_map->in(ex_map->req()-1); 168 if (clear_it) ex_map->del_req(ex_map->req()-1); 169 return ex_oop; 170 } 171 172 //-----------------------------saved_ex_oop------------------------------------ 173 // Recover a saved exception from its map. 174 Node* GraphKit::saved_ex_oop(SafePointNode* ex_map) { 175 return common_saved_ex_oop(ex_map, false); 176 } 177 178 //--------------------------clear_saved_ex_oop--------------------------------- 179 // Erase a previously saved exception from its map. 180 Node* GraphKit::clear_saved_ex_oop(SafePointNode* ex_map) { 181 return common_saved_ex_oop(ex_map, true); 182 } 183 184 #ifdef ASSERT 185 //---------------------------has_saved_ex_oop---------------------------------- 186 // Erase a previously saved exception from its map. 187 bool GraphKit::has_saved_ex_oop(SafePointNode* ex_map) { 188 return ex_map->req() == ex_map->jvms()->endoff()+1; 189 } 190 #endif 191 192 //-------------------------make_exception_state-------------------------------- 193 // Turn the current JVM state into an exception state, appending the ex_oop. 194 SafePointNode* GraphKit::make_exception_state(Node* ex_oop) { 195 sync_jvms(); 196 SafePointNode* ex_map = stop(); // do not manipulate this map any more 197 set_saved_ex_oop(ex_map, ex_oop); 198 return ex_map; 199 } 200 201 202 //--------------------------add_exception_state-------------------------------- 203 // Add an exception to my list of exceptions. 204 void GraphKit::add_exception_state(SafePointNode* ex_map) { 205 if (ex_map == NULL || ex_map->control() == top()) { 206 return; 207 } 208 #ifdef ASSERT 209 verify_exception_state(ex_map); 210 if (has_exceptions()) { 211 assert(ex_map->jvms()->same_calls_as(_exceptions->jvms()), "all collected exceptions must come from the same place"); 212 } 213 #endif 214 215 // If there is already an exception of exactly this type, merge with it. 216 // In particular, null-checks and other low-level exceptions common up here. 217 Node* ex_oop = saved_ex_oop(ex_map); 218 const Type* ex_type = _gvn.type(ex_oop); 219 if (ex_oop == top()) { 220 // No action needed. 221 return; 222 } 223 assert(ex_type->isa_instptr(), "exception must be an instance"); 224 for (SafePointNode* e2 = _exceptions; e2 != NULL; e2 = e2->next_exception()) { 225 const Type* ex_type2 = _gvn.type(saved_ex_oop(e2)); 226 // We check sp also because call bytecodes can generate exceptions 227 // both before and after arguments are popped! 228 if (ex_type2 == ex_type 229 && e2->_jvms->sp() == ex_map->_jvms->sp()) { 230 combine_exception_states(ex_map, e2); 231 return; 232 } 233 } 234 235 // No pre-existing exception of the same type. Chain it on the list. 236 push_exception_state(ex_map); 237 } 238 239 //-----------------------add_exception_states_from----------------------------- 240 void GraphKit::add_exception_states_from(JVMState* jvms) { 241 SafePointNode* ex_map = jvms->map()->next_exception(); 242 if (ex_map != NULL) { 243 jvms->map()->set_next_exception(NULL); 244 for (SafePointNode* next_map; ex_map != NULL; ex_map = next_map) { 245 next_map = ex_map->next_exception(); 246 ex_map->set_next_exception(NULL); 247 add_exception_state(ex_map); 248 } 249 } 250 } 251 252 //-----------------------transfer_exceptions_into_jvms------------------------- 253 JVMState* GraphKit::transfer_exceptions_into_jvms() { 254 if (map() == NULL) { 255 // We need a JVMS to carry the exceptions, but the map has gone away. 256 // Create a scratch JVMS, cloned from any of the exception states... 257 if (has_exceptions()) { 258 _map = _exceptions; 259 _map = clone_map(); 260 _map->set_next_exception(NULL); 261 clear_saved_ex_oop(_map); 262 debug_only(verify_map()); 263 } else { 264 // ...or created from scratch 265 JVMState* jvms = new (C) JVMState(_method, NULL); 266 jvms->set_bci(_bci); 267 jvms->set_sp(_sp); 268 jvms->set_map(new (C, TypeFunc::Parms) SafePointNode(TypeFunc::Parms, jvms)); 269 set_jvms(jvms); 270 for (uint i = 0; i < map()->req(); i++) map()->init_req(i, top()); 271 set_all_memory(top()); 272 while (map()->req() < jvms->endoff()) map()->add_req(top()); 273 } 274 // (This is a kludge, in case you didn't notice.) 275 set_control(top()); 276 } 277 JVMState* jvms = sync_jvms(); 278 assert(!jvms->map()->has_exceptions(), "no exceptions on this map yet"); 279 jvms->map()->set_next_exception(_exceptions); 280 _exceptions = NULL; // done with this set of exceptions 281 return jvms; 282 } 283 284 static inline void add_n_reqs(Node* dstphi, Node* srcphi) { 285 assert(is_hidden_merge(dstphi), "must be a special merge node"); 286 assert(is_hidden_merge(srcphi), "must be a special merge node"); 287 uint limit = srcphi->req(); 288 for (uint i = PhiNode::Input; i < limit; i++) { 289 dstphi->add_req(srcphi->in(i)); 290 } 291 } 292 static inline void add_one_req(Node* dstphi, Node* src) { 293 assert(is_hidden_merge(dstphi), "must be a special merge node"); 294 assert(!is_hidden_merge(src), "must not be a special merge node"); 295 dstphi->add_req(src); 296 } 297 298 //-----------------------combine_exception_states------------------------------ 299 // This helper function combines exception states by building phis on a 300 // specially marked state-merging region. These regions and phis are 301 // untransformed, and can build up gradually. The region is marked by 302 // having a control input of its exception map, rather than NULL. Such 303 // regions do not appear except in this function, and in use_exception_state. 304 void GraphKit::combine_exception_states(SafePointNode* ex_map, SafePointNode* phi_map) { 305 if (failing()) return; // dying anyway... 306 JVMState* ex_jvms = ex_map->_jvms; 307 assert(ex_jvms->same_calls_as(phi_map->_jvms), "consistent call chains"); 308 assert(ex_jvms->stkoff() == phi_map->_jvms->stkoff(), "matching locals"); 309 assert(ex_jvms->sp() == phi_map->_jvms->sp(), "matching stack sizes"); 310 assert(ex_jvms->monoff() == phi_map->_jvms->monoff(), "matching JVMS"); 311 assert(ex_map->req() == phi_map->req(), "matching maps"); 312 uint tos = ex_jvms->stkoff() + ex_jvms->sp(); 313 Node* hidden_merge_mark = root(); 314 Node* region = phi_map->control(); 315 MergeMemNode* phi_mem = phi_map->merged_memory(); 316 MergeMemNode* ex_mem = ex_map->merged_memory(); 317 if (region->in(0) != hidden_merge_mark) { 318 // The control input is not (yet) a specially-marked region in phi_map. 319 // Make it so, and build some phis. 320 region = new (C, 2) RegionNode(2); 321 _gvn.set_type(region, Type::CONTROL); 322 region->set_req(0, hidden_merge_mark); // marks an internal ex-state 323 region->init_req(1, phi_map->control()); 324 phi_map->set_control(region); 325 Node* io_phi = PhiNode::make(region, phi_map->i_o(), Type::ABIO); 326 record_for_igvn(io_phi); 327 _gvn.set_type(io_phi, Type::ABIO); 328 phi_map->set_i_o(io_phi); 329 for (MergeMemStream mms(phi_mem); mms.next_non_empty(); ) { 330 Node* m = mms.memory(); 331 Node* m_phi = PhiNode::make(region, m, Type::MEMORY, mms.adr_type(C)); 332 record_for_igvn(m_phi); 333 _gvn.set_type(m_phi, Type::MEMORY); 334 mms.set_memory(m_phi); 335 } 336 } 337 338 // Either or both of phi_map and ex_map might already be converted into phis. 339 Node* ex_control = ex_map->control(); 340 // if there is special marking on ex_map also, we add multiple edges from src 341 bool add_multiple = (ex_control->in(0) == hidden_merge_mark); 342 // how wide was the destination phi_map, originally? 343 uint orig_width = region->req(); 344 345 if (add_multiple) { 346 add_n_reqs(region, ex_control); 347 add_n_reqs(phi_map->i_o(), ex_map->i_o()); 348 } else { 349 // ex_map has no merges, so we just add single edges everywhere 350 add_one_req(region, ex_control); 351 add_one_req(phi_map->i_o(), ex_map->i_o()); 352 } 353 for (MergeMemStream mms(phi_mem, ex_mem); mms.next_non_empty2(); ) { 354 if (mms.is_empty()) { 355 // get a copy of the base memory, and patch some inputs into it 356 const TypePtr* adr_type = mms.adr_type(C); 357 Node* phi = mms.force_memory()->as_Phi()->slice_memory(adr_type); 358 assert(phi->as_Phi()->region() == mms.base_memory()->in(0), ""); 359 mms.set_memory(phi); 360 // Prepare to append interesting stuff onto the newly sliced phi: 361 while (phi->req() > orig_width) phi->del_req(phi->req()-1); 362 } 363 // Append stuff from ex_map: 364 if (add_multiple) { 365 add_n_reqs(mms.memory(), mms.memory2()); 366 } else { 367 add_one_req(mms.memory(), mms.memory2()); 368 } 369 } 370 uint limit = ex_map->req(); 371 for (uint i = TypeFunc::Parms; i < limit; i++) { 372 // Skip everything in the JVMS after tos. (The ex_oop follows.) 373 if (i == tos) i = ex_jvms->monoff(); 374 Node* src = ex_map->in(i); 375 Node* dst = phi_map->in(i); 376 if (src != dst) { 377 PhiNode* phi; 378 if (dst->in(0) != region) { 379 dst = phi = PhiNode::make(region, dst, _gvn.type(dst)); 380 record_for_igvn(phi); 381 _gvn.set_type(phi, phi->type()); 382 phi_map->set_req(i, dst); 383 // Prepare to append interesting stuff onto the new phi: 384 while (dst->req() > orig_width) dst->del_req(dst->req()-1); 385 } else { 386 assert(dst->is_Phi(), "nobody else uses a hidden region"); 387 phi = (PhiNode*)dst; 388 } 389 if (add_multiple && src->in(0) == ex_control) { 390 // Both are phis. 391 add_n_reqs(dst, src); 392 } else { 393 while (dst->req() < region->req()) add_one_req(dst, src); 394 } 395 const Type* srctype = _gvn.type(src); 396 if (phi->type() != srctype) { 397 const Type* dsttype = phi->type()->meet(srctype); 398 if (phi->type() != dsttype) { 399 phi->set_type(dsttype); 400 _gvn.set_type(phi, dsttype); 401 } 402 } 403 } 404 } 405 } 406 407 //--------------------------use_exception_state-------------------------------- 408 Node* GraphKit::use_exception_state(SafePointNode* phi_map) { 409 if (failing()) { stop(); return top(); } 410 Node* region = phi_map->control(); 411 Node* hidden_merge_mark = root(); 412 assert(phi_map->jvms()->map() == phi_map, "sanity: 1-1 relation"); 413 Node* ex_oop = clear_saved_ex_oop(phi_map); 414 if (region->in(0) == hidden_merge_mark) { 415 // Special marking for internal ex-states. Process the phis now. 416 region->set_req(0, region); // now it's an ordinary region 417 set_jvms(phi_map->jvms()); // ...so now we can use it as a map 418 // Note: Setting the jvms also sets the bci and sp. 419 set_control(_gvn.transform(region)); 420 uint tos = jvms()->stkoff() + sp(); 421 for (uint i = 1; i < tos; i++) { 422 Node* x = phi_map->in(i); 423 if (x->in(0) == region) { 424 assert(x->is_Phi(), "expected a special phi"); 425 phi_map->set_req(i, _gvn.transform(x)); 426 } 427 } 428 for (MergeMemStream mms(merged_memory()); mms.next_non_empty(); ) { 429 Node* x = mms.memory(); 430 if (x->in(0) == region) { 431 assert(x->is_Phi(), "nobody else uses a hidden region"); 432 mms.set_memory(_gvn.transform(x)); 433 } 434 } 435 if (ex_oop->in(0) == region) { 436 assert(ex_oop->is_Phi(), "expected a special phi"); 437 ex_oop = _gvn.transform(ex_oop); 438 } 439 } else { 440 set_jvms(phi_map->jvms()); 441 } 442 443 assert(!is_hidden_merge(phi_map->control()), "hidden ex. states cleared"); 444 assert(!is_hidden_merge(phi_map->i_o()), "hidden ex. states cleared"); 445 return ex_oop; 446 } 447 448 //---------------------------------java_bc------------------------------------- 449 Bytecodes::Code GraphKit::java_bc() const { 450 ciMethod* method = this->method(); 451 int bci = this->bci(); 452 if (method != NULL && bci != InvocationEntryBci) 453 return method->java_code_at_bci(bci); 454 else 455 return Bytecodes::_illegal; 456 } 457 458 //------------------------------builtin_throw---------------------------------- 459 void GraphKit::builtin_throw(Deoptimization::DeoptReason reason, Node* arg) { 460 bool must_throw = true; 461 462 if (JvmtiExport::can_post_exceptions()) { 463 // Do not try anything fancy if we're notifying the VM on every throw. 464 // Cf. case Bytecodes::_athrow in parse2.cpp. 465 uncommon_trap(reason, Deoptimization::Action_none, 466 (ciKlass*)NULL, (char*)NULL, must_throw); 467 return; 468 } 469 470 // If this particular condition has not yet happened at this 471 // bytecode, then use the uncommon trap mechanism, and allow for 472 // a future recompilation if several traps occur here. 473 // If the throw is hot, try to use a more complicated inline mechanism 474 // which keeps execution inside the compiled code. 475 bool treat_throw_as_hot = false; 476 ciMethodData* md = method()->method_data(); 477 478 if (ProfileTraps) { 479 if (too_many_traps(reason)) { 480 treat_throw_as_hot = true; 481 } 482 // (If there is no MDO at all, assume it is early in 483 // execution, and that any deopts are part of the 484 // startup transient, and don't need to be remembered.) 485 486 // Also, if there is a local exception handler, treat all throws 487 // as hot if there has been at least one in this method. 488 if (C->trap_count(reason) != 0 489 && method()->method_data()->trap_count(reason) != 0 490 && has_ex_handler()) { 491 treat_throw_as_hot = true; 492 } 493 } 494 495 // If this throw happens frequently, an uncommon trap might cause 496 // a performance pothole. If there is a local exception handler, 497 // and if this particular bytecode appears to be deoptimizing often, 498 // let us handle the throw inline, with a preconstructed instance. 499 // Note: If the deopt count has blown up, the uncommon trap 500 // runtime is going to flush this nmethod, not matter what. 501 if (treat_throw_as_hot 502 && (!StackTraceInThrowable || OmitStackTraceInFastThrow)) { 503 // If the throw is local, we use a pre-existing instance and 504 // punt on the backtrace. This would lead to a missing backtrace 505 // (a repeat of 4292742) if the backtrace object is ever asked 506 // for its backtrace. 507 // Fixing this remaining case of 4292742 requires some flavor of 508 // escape analysis. Leave that for the future. 509 ciInstance* ex_obj = NULL; 510 switch (reason) { 511 case Deoptimization::Reason_null_check: 512 ex_obj = env()->NullPointerException_instance(); 513 break; 514 case Deoptimization::Reason_div0_check: 515 ex_obj = env()->ArithmeticException_instance(); 516 break; 517 case Deoptimization::Reason_range_check: 518 ex_obj = env()->ArrayIndexOutOfBoundsException_instance(); 519 break; 520 case Deoptimization::Reason_class_check: 521 if (java_bc() == Bytecodes::_aastore) { 522 ex_obj = env()->ArrayStoreException_instance(); 523 } else { 524 ex_obj = env()->ClassCastException_instance(); 525 } 526 break; 527 } 528 if (failing()) { stop(); return; } // exception allocation might fail 529 if (ex_obj != NULL) { 530 // Cheat with a preallocated exception object. 531 if (C->log() != NULL) 532 C->log()->elem("hot_throw preallocated='1' reason='%s'", 533 Deoptimization::trap_reason_name(reason)); 534 const TypeInstPtr* ex_con = TypeInstPtr::make(ex_obj); 535 Node* ex_node = _gvn.transform( ConNode::make(C, ex_con) ); 536 537 // Clear the detail message of the preallocated exception object. 538 // Weblogic sometimes mutates the detail message of exceptions 539 // using reflection. 540 int offset = java_lang_Throwable::get_detailMessage_offset(); 541 const TypePtr* adr_typ = ex_con->add_offset(offset); 542 543 Node *adr = basic_plus_adr(ex_node, ex_node, offset); 544 Node *store = store_oop_to_object(control(), ex_node, adr, adr_typ, null(), ex_con, T_OBJECT); 545 546 add_exception_state(make_exception_state(ex_node)); 547 return; 548 } 549 } 550 551 // %%% Maybe add entry to OptoRuntime which directly throws the exc.? 552 // It won't be much cheaper than bailing to the interp., since we'll 553 // have to pass up all the debug-info, and the runtime will have to 554 // create the stack trace. 555 556 // Usual case: Bail to interpreter. 557 // Reserve the right to recompile if we haven't seen anything yet. 558 559 Deoptimization::DeoptAction action = Deoptimization::Action_maybe_recompile; 560 if (treat_throw_as_hot 561 && (method()->method_data()->trap_recompiled_at(bci()) 562 || C->too_many_traps(reason))) { 563 // We cannot afford to take more traps here. Suffer in the interpreter. 564 if (C->log() != NULL) 565 C->log()->elem("hot_throw preallocated='0' reason='%s' mcount='%d'", 566 Deoptimization::trap_reason_name(reason), 567 C->trap_count(reason)); 568 action = Deoptimization::Action_none; 569 } 570 571 // "must_throw" prunes the JVM state to include only the stack, if there 572 // are no local exception handlers. This should cut down on register 573 // allocation time and code size, by drastically reducing the number 574 // of in-edges on the call to the uncommon trap. 575 576 uncommon_trap(reason, action, (ciKlass*)NULL, (char*)NULL, must_throw); 577 } 578 579 580 //----------------------------PreserveJVMState--------------------------------- 581 PreserveJVMState::PreserveJVMState(GraphKit* kit, bool clone_map) { 582 debug_only(kit->verify_map()); 583 _kit = kit; 584 _map = kit->map(); // preserve the map 585 _sp = kit->sp(); 586 kit->set_map(clone_map ? kit->clone_map() : NULL); 587 #ifdef ASSERT 588 _bci = kit->bci(); 589 Parse* parser = kit->is_Parse(); 590 int block = (parser == NULL || parser->block() == NULL) ? -1 : parser->block()->rpo(); 591 _block = block; 592 #endif 593 } 594 PreserveJVMState::~PreserveJVMState() { 595 GraphKit* kit = _kit; 596 #ifdef ASSERT 597 assert(kit->bci() == _bci, "bci must not shift"); 598 Parse* parser = kit->is_Parse(); 599 int block = (parser == NULL || parser->block() == NULL) ? -1 : parser->block()->rpo(); 600 assert(block == _block, "block must not shift"); 601 #endif 602 kit->set_map(_map); 603 kit->set_sp(_sp); 604 } 605 606 607 //-----------------------------BuildCutout------------------------------------- 608 BuildCutout::BuildCutout(GraphKit* kit, Node* p, float prob, float cnt) 609 : PreserveJVMState(kit) 610 { 611 assert(p->is_Con() || p->is_Bool(), "test must be a bool"); 612 SafePointNode* outer_map = _map; // preserved map is caller's 613 SafePointNode* inner_map = kit->map(); 614 IfNode* iff = kit->create_and_map_if(outer_map->control(), p, prob, cnt); 615 outer_map->set_control(kit->gvn().transform( new (kit->C, 1) IfTrueNode(iff) )); 616 inner_map->set_control(kit->gvn().transform( new (kit->C, 1) IfFalseNode(iff) )); 617 } 618 BuildCutout::~BuildCutout() { 619 GraphKit* kit = _kit; 620 assert(kit->stopped(), "cutout code must stop, throw, return, etc."); 621 } 622 623 624 //------------------------------clone_map-------------------------------------- 625 // Implementation of PreserveJVMState 626 // 627 // Only clone_map(...) here. If this function is only used in the 628 // PreserveJVMState class we may want to get rid of this extra 629 // function eventually and do it all there. 630 631 SafePointNode* GraphKit::clone_map() { 632 if (map() == NULL) return NULL; 633 634 // Clone the memory edge first 635 Node* mem = MergeMemNode::make(C, map()->memory()); 636 gvn().set_type_bottom(mem); 637 638 SafePointNode *clonemap = (SafePointNode*)map()->clone(); 639 JVMState* jvms = this->jvms(); 640 JVMState* clonejvms = jvms->clone_shallow(C); 641 clonemap->set_memory(mem); 642 clonemap->set_jvms(clonejvms); 643 clonejvms->set_map(clonemap); 644 record_for_igvn(clonemap); 645 gvn().set_type_bottom(clonemap); 646 return clonemap; 647 } 648 649 650 //-----------------------------set_map_clone----------------------------------- 651 void GraphKit::set_map_clone(SafePointNode* m) { 652 _map = m; 653 _map = clone_map(); 654 _map->set_next_exception(NULL); 655 debug_only(verify_map()); 656 } 657 658 659 //----------------------------kill_dead_locals--------------------------------- 660 // Detect any locals which are known to be dead, and force them to top. 661 void GraphKit::kill_dead_locals() { 662 // Consult the liveness information for the locals. If any 663 // of them are unused, then they can be replaced by top(). This 664 // should help register allocation time and cut down on the size 665 // of the deoptimization information. 666 667 // This call is made from many of the bytecode handling 668 // subroutines called from the Big Switch in do_one_bytecode. 669 // Every bytecode which might include a slow path is responsible 670 // for killing its dead locals. The more consistent we 671 // are about killing deads, the fewer useless phis will be 672 // constructed for them at various merge points. 673 674 // bci can be -1 (InvocationEntryBci). We return the entry 675 // liveness for the method. 676 677 if (method() == NULL || method()->code_size() == 0) { 678 // We are building a graph for a call to a native method. 679 // All locals are live. 680 return; 681 } 682 683 ResourceMark rm; 684 685 // Consult the liveness information for the locals. If any 686 // of them are unused, then they can be replaced by top(). This 687 // should help register allocation time and cut down on the size 688 // of the deoptimization information. 689 MethodLivenessResult live_locals = method()->liveness_at_bci(bci()); 690 691 int len = (int)live_locals.size(); 692 assert(len <= jvms()->loc_size(), "too many live locals"); 693 for (int local = 0; local < len; local++) { 694 if (!live_locals.at(local)) { 695 set_local(local, top()); 696 } 697 } 698 } 699 700 #ifdef ASSERT 701 //-------------------------dead_locals_are_killed------------------------------ 702 // Return true if all dead locals are set to top in the map. 703 // Used to assert "clean" debug info at various points. 704 bool GraphKit::dead_locals_are_killed() { 705 if (method() == NULL || method()->code_size() == 0) { 706 // No locals need to be dead, so all is as it should be. 707 return true; 708 } 709 710 // Make sure somebody called kill_dead_locals upstream. 711 ResourceMark rm; 712 for (JVMState* jvms = this->jvms(); jvms != NULL; jvms = jvms->caller()) { 713 if (jvms->loc_size() == 0) continue; // no locals to consult 714 SafePointNode* map = jvms->map(); 715 ciMethod* method = jvms->method(); 716 int bci = jvms->bci(); 717 if (jvms == this->jvms()) { 718 bci = this->bci(); // it might not yet be synched 719 } 720 MethodLivenessResult live_locals = method->liveness_at_bci(bci); 721 int len = (int)live_locals.size(); 722 if (!live_locals.is_valid() || len == 0) 723 // This method is trivial, or is poisoned by a breakpoint. 724 return true; 725 assert(len == jvms->loc_size(), "live map consistent with locals map"); 726 for (int local = 0; local < len; local++) { 727 if (!live_locals.at(local) && map->local(jvms, local) != top()) { 728 if (PrintMiscellaneous && (Verbose || WizardMode)) { 729 tty->print_cr("Zombie local %d: ", local); 730 jvms->dump(); 731 } 732 return false; 733 } 734 } 735 } 736 return true; 737 } 738 739 #endif //ASSERT 740 741 // Helper function for adding JVMState and debug information to node 742 void GraphKit::add_safepoint_edges(SafePointNode* call, bool must_throw) { 743 // Add the safepoint edges to the call (or other safepoint). 744 745 // Make sure dead locals are set to top. This 746 // should help register allocation time and cut down on the size 747 // of the deoptimization information. 748 assert(dead_locals_are_killed(), "garbage in debug info before safepoint"); 749 750 // Walk the inline list to fill in the correct set of JVMState's 751 // Also fill in the associated edges for each JVMState. 752 753 JVMState* youngest_jvms = sync_jvms(); 754 755 // Do we need debug info here? If it is a SafePoint and this method 756 // cannot de-opt, then we do NOT need any debug info. 757 bool full_info = (C->deopt_happens() || call->Opcode() != Op_SafePoint); 758 759 // If we are guaranteed to throw, we can prune everything but the 760 // input to the current bytecode. 761 bool can_prune_locals = false; 762 uint stack_slots_not_pruned = 0; 763 int inputs = 0, depth = 0; 764 if (must_throw) { 765 assert(method() == youngest_jvms->method(), "sanity"); 766 if (compute_stack_effects(inputs, depth)) { 767 can_prune_locals = true; 768 stack_slots_not_pruned = inputs; 769 } 770 } 771 772 if (JvmtiExport::can_examine_or_deopt_anywhere()) { 773 // At any safepoint, this method can get breakpointed, which would 774 // then require an immediate deoptimization. 775 full_info = true; 776 can_prune_locals = false; // do not prune locals 777 stack_slots_not_pruned = 0; 778 } 779 780 // do not scribble on the input jvms 781 JVMState* out_jvms = youngest_jvms->clone_deep(C); 782 call->set_jvms(out_jvms); // Start jvms list for call node 783 784 // Presize the call: 785 debug_only(uint non_debug_edges = call->req()); 786 call->add_req_batch(top(), youngest_jvms->debug_depth()); 787 assert(call->req() == non_debug_edges + youngest_jvms->debug_depth(), ""); 788 789 // Set up edges so that the call looks like this: 790 // Call [state:] ctl io mem fptr retadr 791 // [parms:] parm0 ... parmN 792 // [root:] loc0 ... locN stk0 ... stkSP mon0 obj0 ... monN objN 793 // [...mid:] loc0 ... locN stk0 ... stkSP mon0 obj0 ... monN objN [...] 794 // [young:] loc0 ... locN stk0 ... stkSP mon0 obj0 ... monN objN 795 // Note that caller debug info precedes callee debug info. 796 797 // Fill pointer walks backwards from "young:" to "root:" in the diagram above: 798 uint debug_ptr = call->req(); 799 800 // Loop over the map input edges associated with jvms, add them 801 // to the call node, & reset all offsets to match call node array. 802 for (JVMState* in_jvms = youngest_jvms; in_jvms != NULL; ) { 803 uint debug_end = debug_ptr; 804 uint debug_start = debug_ptr - in_jvms->debug_size(); 805 debug_ptr = debug_start; // back up the ptr 806 807 uint p = debug_start; // walks forward in [debug_start, debug_end) 808 uint j, k, l; 809 SafePointNode* in_map = in_jvms->map(); 810 out_jvms->set_map(call); 811 812 if (can_prune_locals) { 813 assert(in_jvms->method() == out_jvms->method(), "sanity"); 814 // If the current throw can reach an exception handler in this JVMS, 815 // then we must keep everything live that can reach that handler. 816 // As a quick and dirty approximation, we look for any handlers at all. 817 if (in_jvms->method()->has_exception_handlers()) { 818 can_prune_locals = false; 819 } 820 } 821 822 // Add the Locals 823 k = in_jvms->locoff(); 824 l = in_jvms->loc_size(); 825 out_jvms->set_locoff(p); 826 if (full_info && !can_prune_locals) { 827 for (j = 0; j < l; j++) 828 call->set_req(p++, in_map->in(k+j)); 829 } else { 830 p += l; // already set to top above by add_req_batch 831 } 832 833 // Add the Expression Stack 834 k = in_jvms->stkoff(); 835 l = in_jvms->sp(); 836 out_jvms->set_stkoff(p); 837 if (full_info && !can_prune_locals) { 838 for (j = 0; j < l; j++) 839 call->set_req(p++, in_map->in(k+j)); 840 } else if (can_prune_locals && stack_slots_not_pruned != 0) { 841 // Divide stack into {S0,...,S1}, where S0 is set to top. 842 uint s1 = stack_slots_not_pruned; 843 stack_slots_not_pruned = 0; // for next iteration 844 if (s1 > l) s1 = l; 845 uint s0 = l - s1; 846 p += s0; // skip the tops preinstalled by add_req_batch 847 for (j = s0; j < l; j++) 848 call->set_req(p++, in_map->in(k+j)); 849 } else { 850 p += l; // already set to top above by add_req_batch 851 } 852 853 // Add the Monitors 854 k = in_jvms->monoff(); 855 l = in_jvms->mon_size(); 856 out_jvms->set_monoff(p); 857 for (j = 0; j < l; j++) 858 call->set_req(p++, in_map->in(k+j)); 859 860 // Copy any scalar object fields. 861 k = in_jvms->scloff(); 862 l = in_jvms->scl_size(); 863 out_jvms->set_scloff(p); 864 for (j = 0; j < l; j++) 865 call->set_req(p++, in_map->in(k+j)); 866 867 // Finish the new jvms. 868 out_jvms->set_endoff(p); 869 870 assert(out_jvms->endoff() == debug_end, "fill ptr must match"); 871 assert(out_jvms->depth() == in_jvms->depth(), "depth must match"); 872 assert(out_jvms->loc_size() == in_jvms->loc_size(), "size must match"); 873 assert(out_jvms->mon_size() == in_jvms->mon_size(), "size must match"); 874 assert(out_jvms->scl_size() == in_jvms->scl_size(), "size must match"); 875 assert(out_jvms->debug_size() == in_jvms->debug_size(), "size must match"); 876 877 // Update the two tail pointers in parallel. 878 out_jvms = out_jvms->caller(); 879 in_jvms = in_jvms->caller(); 880 } 881 882 assert(debug_ptr == non_debug_edges, "debug info must fit exactly"); 883 884 // Test the correctness of JVMState::debug_xxx accessors: 885 assert(call->jvms()->debug_start() == non_debug_edges, ""); 886 assert(call->jvms()->debug_end() == call->req(), ""); 887 assert(call->jvms()->debug_depth() == call->req() - non_debug_edges, ""); 888 } 889 890 bool GraphKit::compute_stack_effects(int& inputs, int& depth) { 891 Bytecodes::Code code = java_bc(); 892 if (code == Bytecodes::_wide) { 893 code = method()->java_code_at_bci(bci() + 1); 894 } 895 896 BasicType rtype = T_ILLEGAL; 897 int rsize = 0; 898 899 if (code != Bytecodes::_illegal) { 900 depth = Bytecodes::depth(code); // checkcast=0, athrow=-1 901 rtype = Bytecodes::result_type(code); // checkcast=P, athrow=V 902 if (rtype < T_CONFLICT) 903 rsize = type2size[rtype]; 904 } 905 906 switch (code) { 907 case Bytecodes::_illegal: 908 return false; 909 910 case Bytecodes::_ldc: 911 case Bytecodes::_ldc_w: 912 case Bytecodes::_ldc2_w: 913 inputs = 0; 914 break; 915 916 case Bytecodes::_dup: inputs = 1; break; 917 case Bytecodes::_dup_x1: inputs = 2; break; 918 case Bytecodes::_dup_x2: inputs = 3; break; 919 case Bytecodes::_dup2: inputs = 2; break; 920 case Bytecodes::_dup2_x1: inputs = 3; break; 921 case Bytecodes::_dup2_x2: inputs = 4; break; 922 case Bytecodes::_swap: inputs = 2; break; 923 case Bytecodes::_arraylength: inputs = 1; break; 924 925 case Bytecodes::_getstatic: 926 case Bytecodes::_putstatic: 927 case Bytecodes::_getfield: 928 case Bytecodes::_putfield: 929 { 930 bool is_get = (depth >= 0), is_static = (depth & 1); 931 bool ignore; 932 ciBytecodeStream iter(method()); 933 iter.reset_to_bci(bci()); 934 iter.next(); 935 ciField* field = iter.get_field(ignore); 936 int size = field->type()->size(); 937 inputs = (is_static ? 0 : 1); 938 if (is_get) { 939 depth = size - inputs; 940 } else { 941 inputs += size; // putxxx pops the value from the stack 942 depth = - inputs; 943 } 944 } 945 break; 946 947 case Bytecodes::_invokevirtual: 948 case Bytecodes::_invokespecial: 949 case Bytecodes::_invokestatic: 950 case Bytecodes::_invokedynamic: 951 case Bytecodes::_invokeinterface: 952 { 953 bool is_static = (depth == 0); 954 bool ignore; 955 ciBytecodeStream iter(method()); 956 iter.reset_to_bci(bci()); 957 iter.next(); 958 ciMethod* method = iter.get_method(ignore); 959 inputs = method->arg_size_no_receiver(); 960 if (!is_static) inputs += 1; 961 int size = method->return_type()->size(); 962 depth = size - inputs; 963 } 964 break; 965 966 case Bytecodes::_multianewarray: 967 { 968 ciBytecodeStream iter(method()); 969 iter.reset_to_bci(bci()); 970 iter.next(); 971 inputs = iter.get_dimensions(); 972 assert(rsize == 1, ""); 973 depth = rsize - inputs; 974 } 975 break; 976 977 case Bytecodes::_ireturn: 978 case Bytecodes::_lreturn: 979 case Bytecodes::_freturn: 980 case Bytecodes::_dreturn: 981 case Bytecodes::_areturn: 982 assert(rsize = -depth, ""); 983 inputs = rsize; 984 break; 985 986 case Bytecodes::_jsr: 987 case Bytecodes::_jsr_w: 988 inputs = 0; 989 depth = 1; // S.B. depth=1, not zero 990 break; 991 992 default: 993 // bytecode produces a typed result 994 inputs = rsize - depth; 995 assert(inputs >= 0, ""); 996 break; 997 } 998 999 #ifdef ASSERT 1000 // spot check 1001 int outputs = depth + inputs; 1002 assert(outputs >= 0, "sanity"); 1003 switch (code) { 1004 case Bytecodes::_checkcast: assert(inputs == 1 && outputs == 1, ""); break; 1005 case Bytecodes::_athrow: assert(inputs == 1 && outputs == 0, ""); break; 1006 case Bytecodes::_aload_0: assert(inputs == 0 && outputs == 1, ""); break; 1007 case Bytecodes::_return: assert(inputs == 0 && outputs == 0, ""); break; 1008 case Bytecodes::_drem: assert(inputs == 4 && outputs == 2, ""); break; 1009 } 1010 #endif //ASSERT 1011 1012 return true; 1013 } 1014 1015 1016 1017 //------------------------------basic_plus_adr--------------------------------- 1018 Node* GraphKit::basic_plus_adr(Node* base, Node* ptr, Node* offset) { 1019 // short-circuit a common case 1020 if (offset == intcon(0)) return ptr; 1021 return _gvn.transform( new (C, 4) AddPNode(base, ptr, offset) ); 1022 } 1023 1024 Node* GraphKit::ConvI2L(Node* offset) { 1025 // short-circuit a common case 1026 jint offset_con = find_int_con(offset, Type::OffsetBot); 1027 if (offset_con != Type::OffsetBot) { 1028 return longcon((long) offset_con); 1029 } 1030 return _gvn.transform( new (C, 2) ConvI2LNode(offset)); 1031 } 1032 Node* GraphKit::ConvL2I(Node* offset) { 1033 // short-circuit a common case 1034 jlong offset_con = find_long_con(offset, (jlong)Type::OffsetBot); 1035 if (offset_con != (jlong)Type::OffsetBot) { 1036 return intcon((int) offset_con); 1037 } 1038 return _gvn.transform( new (C, 2) ConvL2INode(offset)); 1039 } 1040 1041 //-------------------------load_object_klass----------------------------------- 1042 Node* GraphKit::load_object_klass(Node* obj) { 1043 // Special-case a fresh allocation to avoid building nodes: 1044 Node* akls = AllocateNode::Ideal_klass(obj, &_gvn); 1045 if (akls != NULL) return akls; 1046 Node* k_adr = basic_plus_adr(obj, oopDesc::klass_offset_in_bytes()); 1047 return _gvn.transform( LoadKlassNode::make(_gvn, immutable_memory(), k_adr, TypeInstPtr::KLASS) ); 1048 } 1049 1050 //-------------------------load_array_length----------------------------------- 1051 Node* GraphKit::load_array_length(Node* array) { 1052 // Special-case a fresh allocation to avoid building nodes: 1053 AllocateArrayNode* alloc = AllocateArrayNode::Ideal_array_allocation(array, &_gvn); 1054 Node *alen; 1055 if (alloc == NULL) { 1056 Node *r_adr = basic_plus_adr(array, arrayOopDesc::length_offset_in_bytes()); 1057 alen = _gvn.transform( new (C, 3) LoadRangeNode(0, immutable_memory(), r_adr, TypeInt::POS)); 1058 } else { 1059 alen = alloc->Ideal_length(); 1060 Node* ccast = alloc->make_ideal_length(_gvn.type(array)->is_aryptr(), &_gvn); 1061 if (ccast != alen) { 1062 alen = _gvn.transform(ccast); 1063 } 1064 } 1065 return alen; 1066 } 1067 1068 //------------------------------do_null_check---------------------------------- 1069 // Helper function to do a NULL pointer check. Returned value is 1070 // the incoming address with NULL casted away. You are allowed to use the 1071 // not-null value only if you are control dependent on the test. 1072 extern int explicit_null_checks_inserted, 1073 explicit_null_checks_elided; 1074 Node* GraphKit::null_check_common(Node* value, BasicType type, 1075 // optional arguments for variations: 1076 bool assert_null, 1077 Node* *null_control) { 1078 assert(!assert_null || null_control == NULL, "not both at once"); 1079 if (stopped()) return top(); 1080 if (!GenerateCompilerNullChecks && !assert_null && null_control == NULL) { 1081 // For some performance testing, we may wish to suppress null checking. 1082 value = cast_not_null(value); // Make it appear to be non-null (4962416). 1083 return value; 1084 } 1085 explicit_null_checks_inserted++; 1086 1087 // Construct NULL check 1088 Node *chk = NULL; 1089 switch(type) { 1090 case T_LONG : chk = new (C, 3) CmpLNode(value, _gvn.zerocon(T_LONG)); break; 1091 case T_INT : chk = new (C, 3) CmpINode( value, _gvn.intcon(0)); break; 1092 case T_ARRAY : // fall through 1093 type = T_OBJECT; // simplify further tests 1094 case T_OBJECT : { 1095 const Type *t = _gvn.type( value ); 1096 1097 const TypeInstPtr* tp = t->isa_instptr(); 1098 if (tp != NULL && !tp->klass()->is_loaded() 1099 // Only for do_null_check, not any of its siblings: 1100 && !assert_null && null_control == NULL) { 1101 // Usually, any field access or invocation on an unloaded oop type 1102 // will simply fail to link, since the statically linked class is 1103 // likely also to be unloaded. However, in -Xcomp mode, sometimes 1104 // the static class is loaded but the sharper oop type is not. 1105 // Rather than checking for this obscure case in lots of places, 1106 // we simply observe that a null check on an unloaded class 1107 // will always be followed by a nonsense operation, so we 1108 // can just issue the uncommon trap here. 1109 // Our access to the unloaded class will only be correct 1110 // after it has been loaded and initialized, which requires 1111 // a trip through the interpreter. 1112 #ifndef PRODUCT 1113 if (WizardMode) { tty->print("Null check of unloaded "); tp->klass()->print(); tty->cr(); } 1114 #endif 1115 uncommon_trap(Deoptimization::Reason_unloaded, 1116 Deoptimization::Action_reinterpret, 1117 tp->klass(), "!loaded"); 1118 return top(); 1119 } 1120 1121 if (assert_null) { 1122 // See if the type is contained in NULL_PTR. 1123 // If so, then the value is already null. 1124 if (t->higher_equal(TypePtr::NULL_PTR)) { 1125 explicit_null_checks_elided++; 1126 return value; // Elided null assert quickly! 1127 } 1128 } else { 1129 // See if mixing in the NULL pointer changes type. 1130 // If so, then the NULL pointer was not allowed in the original 1131 // type. In other words, "value" was not-null. 1132 if (t->meet(TypePtr::NULL_PTR) != t) { 1133 // same as: if (!TypePtr::NULL_PTR->higher_equal(t)) ... 1134 explicit_null_checks_elided++; 1135 return value; // Elided null check quickly! 1136 } 1137 } 1138 chk = new (C, 3) CmpPNode( value, null() ); 1139 break; 1140 } 1141 1142 default : ShouldNotReachHere(); 1143 } 1144 assert(chk != NULL, "sanity check"); 1145 chk = _gvn.transform(chk); 1146 1147 BoolTest::mask btest = assert_null ? BoolTest::eq : BoolTest::ne; 1148 BoolNode *btst = new (C, 2) BoolNode( chk, btest); 1149 Node *tst = _gvn.transform( btst ); 1150 1151 //----------- 1152 // if peephole optimizations occurred, a prior test existed. 1153 // If a prior test existed, maybe it dominates as we can avoid this test. 1154 if (tst != btst && type == T_OBJECT) { 1155 // At this point we want to scan up the CFG to see if we can 1156 // find an identical test (and so avoid this test altogether). 1157 Node *cfg = control(); 1158 int depth = 0; 1159 while( depth < 16 ) { // Limit search depth for speed 1160 if( cfg->Opcode() == Op_IfTrue && 1161 cfg->in(0)->in(1) == tst ) { 1162 // Found prior test. Use "cast_not_null" to construct an identical 1163 // CastPP (and hence hash to) as already exists for the prior test. 1164 // Return that casted value. 1165 if (assert_null) { 1166 replace_in_map(value, null()); 1167 return null(); // do not issue the redundant test 1168 } 1169 Node *oldcontrol = control(); 1170 set_control(cfg); 1171 Node *res = cast_not_null(value); 1172 set_control(oldcontrol); 1173 explicit_null_checks_elided++; 1174 return res; 1175 } 1176 cfg = IfNode::up_one_dom(cfg, /*linear_only=*/ true); 1177 if (cfg == NULL) break; // Quit at region nodes 1178 depth++; 1179 } 1180 } 1181 1182 //----------- 1183 // Branch to failure if null 1184 float ok_prob = PROB_MAX; // a priori estimate: nulls never happen 1185 Deoptimization::DeoptReason reason; 1186 if (assert_null) 1187 reason = Deoptimization::Reason_null_assert; 1188 else if (type == T_OBJECT) 1189 reason = Deoptimization::Reason_null_check; 1190 else 1191 reason = Deoptimization::Reason_div0_check; 1192 1193 // %%% Since Reason_unhandled is not recorded on a per-bytecode basis, 1194 // ciMethodData::has_trap_at will return a conservative -1 if any 1195 // must-be-null assertion has failed. This could cause performance 1196 // problems for a method after its first do_null_assert failure. 1197 // Consider using 'Reason_class_check' instead? 1198 1199 // To cause an implicit null check, we set the not-null probability 1200 // to the maximum (PROB_MAX). For an explicit check the probability 1201 // is set to a smaller value. 1202 if (null_control != NULL || too_many_traps(reason)) { 1203 // probability is less likely 1204 ok_prob = PROB_LIKELY_MAG(3); 1205 } else if (!assert_null && 1206 (ImplicitNullCheckThreshold > 0) && 1207 method() != NULL && 1208 (method()->method_data()->trap_count(reason) 1209 >= (uint)ImplicitNullCheckThreshold)) { 1210 ok_prob = PROB_LIKELY_MAG(3); 1211 } 1212 1213 if (null_control != NULL) { 1214 IfNode* iff = create_and_map_if(control(), tst, ok_prob, COUNT_UNKNOWN); 1215 Node* null_true = _gvn.transform( new (C, 1) IfFalseNode(iff)); 1216 set_control( _gvn.transform( new (C, 1) IfTrueNode(iff))); 1217 if (null_true == top()) 1218 explicit_null_checks_elided++; 1219 (*null_control) = null_true; 1220 } else { 1221 BuildCutout unless(this, tst, ok_prob); 1222 // Check for optimizer eliding test at parse time 1223 if (stopped()) { 1224 // Failure not possible; do not bother making uncommon trap. 1225 explicit_null_checks_elided++; 1226 } else if (assert_null) { 1227 uncommon_trap(reason, 1228 Deoptimization::Action_make_not_entrant, 1229 NULL, "assert_null"); 1230 } else { 1231 replace_in_map(value, zerocon(type)); 1232 builtin_throw(reason); 1233 } 1234 } 1235 1236 // Must throw exception, fall-thru not possible? 1237 if (stopped()) { 1238 return top(); // No result 1239 } 1240 1241 if (assert_null) { 1242 // Cast obj to null on this path. 1243 replace_in_map(value, zerocon(type)); 1244 return zerocon(type); 1245 } 1246 1247 // Cast obj to not-null on this path, if there is no null_control. 1248 // (If there is a null_control, a non-null value may come back to haunt us.) 1249 if (type == T_OBJECT) { 1250 Node* cast = cast_not_null(value, false); 1251 if (null_control == NULL || (*null_control) == top()) 1252 replace_in_map(value, cast); 1253 value = cast; 1254 } 1255 1256 return value; 1257 } 1258 1259 1260 //------------------------------cast_not_null---------------------------------- 1261 // Cast obj to not-null on this path 1262 Node* GraphKit::cast_not_null(Node* obj, bool do_replace_in_map) { 1263 const Type *t = _gvn.type(obj); 1264 const Type *t_not_null = t->join(TypePtr::NOTNULL); 1265 // Object is already not-null? 1266 if( t == t_not_null ) return obj; 1267 1268 Node *cast = new (C, 2) CastPPNode(obj,t_not_null); 1269 cast->init_req(0, control()); 1270 cast = _gvn.transform( cast ); 1271 1272 // Scan for instances of 'obj' in the current JVM mapping. 1273 // These instances are known to be not-null after the test. 1274 if (do_replace_in_map) 1275 replace_in_map(obj, cast); 1276 1277 return cast; // Return casted value 1278 } 1279 1280 1281 //--------------------------replace_in_map------------------------------------- 1282 void GraphKit::replace_in_map(Node* old, Node* neww) { 1283 this->map()->replace_edge(old, neww); 1284 1285 // Note: This operation potentially replaces any edge 1286 // on the map. This includes locals, stack, and monitors 1287 // of the current (innermost) JVM state. 1288 1289 // We can consider replacing in caller maps. 1290 // The idea would be that an inlined function's null checks 1291 // can be shared with the entire inlining tree. 1292 // The expense of doing this is that the PreserveJVMState class 1293 // would have to preserve caller states too, with a deep copy. 1294 } 1295 1296 1297 1298 //============================================================================= 1299 //--------------------------------memory--------------------------------------- 1300 Node* GraphKit::memory(uint alias_idx) { 1301 MergeMemNode* mem = merged_memory(); 1302 Node* p = mem->memory_at(alias_idx); 1303 _gvn.set_type(p, Type::MEMORY); // must be mapped 1304 return p; 1305 } 1306 1307 //-----------------------------reset_memory------------------------------------ 1308 Node* GraphKit::reset_memory() { 1309 Node* mem = map()->memory(); 1310 // do not use this node for any more parsing! 1311 debug_only( map()->set_memory((Node*)NULL) ); 1312 return _gvn.transform( mem ); 1313 } 1314 1315 //------------------------------set_all_memory--------------------------------- 1316 void GraphKit::set_all_memory(Node* newmem) { 1317 Node* mergemem = MergeMemNode::make(C, newmem); 1318 gvn().set_type_bottom(mergemem); 1319 map()->set_memory(mergemem); 1320 } 1321 1322 //------------------------------set_all_memory_call---------------------------- 1323 void GraphKit::set_all_memory_call(Node* call) { 1324 Node* newmem = _gvn.transform( new (C, 1) ProjNode(call, TypeFunc::Memory) ); 1325 set_all_memory(newmem); 1326 } 1327 1328 //============================================================================= 1329 // 1330 // parser factory methods for MemNodes 1331 // 1332 // These are layered on top of the factory methods in LoadNode and StoreNode, 1333 // and integrate with the parser's memory state and _gvn engine. 1334 // 1335 1336 // factory methods in "int adr_idx" 1337 Node* GraphKit::make_load(Node* ctl, Node* adr, const Type* t, BasicType bt, 1338 int adr_idx, 1339 bool require_atomic_access) { 1340 assert(adr_idx != Compile::AliasIdxTop, "use other make_load factory" ); 1341 const TypePtr* adr_type = NULL; // debug-mode-only argument 1342 debug_only(adr_type = C->get_adr_type(adr_idx)); 1343 Node* mem = memory(adr_idx); 1344 Node* ld; 1345 if (require_atomic_access && bt == T_LONG) { 1346 ld = LoadLNode::make_atomic(C, ctl, mem, adr, adr_type, t); 1347 } else { 1348 ld = LoadNode::make(_gvn, ctl, mem, adr, adr_type, t, bt); 1349 } 1350 return _gvn.transform(ld); 1351 } 1352 1353 Node* GraphKit::store_to_memory(Node* ctl, Node* adr, Node *val, BasicType bt, 1354 int adr_idx, 1355 bool require_atomic_access) { 1356 assert(adr_idx != Compile::AliasIdxTop, "use other store_to_memory factory" ); 1357 const TypePtr* adr_type = NULL; 1358 debug_only(adr_type = C->get_adr_type(adr_idx)); 1359 Node *mem = memory(adr_idx); 1360 Node* st; 1361 if (require_atomic_access && bt == T_LONG) { 1362 st = StoreLNode::make_atomic(C, ctl, mem, adr, adr_type, val); 1363 } else { 1364 st = StoreNode::make(_gvn, ctl, mem, adr, adr_type, val, bt); 1365 } 1366 st = _gvn.transform(st); 1367 set_memory(st, adr_idx); 1368 // Back-to-back stores can only remove intermediate store with DU info 1369 // so push on worklist for optimizer. 1370 if (mem->req() > MemNode::Address && adr == mem->in(MemNode::Address)) 1371 record_for_igvn(st); 1372 1373 return st; 1374 } 1375 1376 void GraphKit::pre_barrier(Node* ctl, 1377 Node* obj, 1378 Node* adr, 1379 uint adr_idx, 1380 Node *val, 1381 const Type* val_type, 1382 BasicType bt) { 1383 BarrierSet* bs = Universe::heap()->barrier_set(); 1384 set_control(ctl); 1385 switch (bs->kind()) { 1386 case BarrierSet::G1SATBCT: 1387 case BarrierSet::G1SATBCTLogging: 1388 g1_write_barrier_pre(obj, adr, adr_idx, val, val_type, bt); 1389 break; 1390 1391 case BarrierSet::CardTableModRef: 1392 case BarrierSet::CardTableExtension: 1393 case BarrierSet::ModRef: 1394 break; 1395 1396 case BarrierSet::Other: 1397 default : 1398 ShouldNotReachHere(); 1399 1400 } 1401 } 1402 1403 void GraphKit::post_barrier(Node* ctl, 1404 Node* store, 1405 Node* obj, 1406 Node* adr, 1407 uint adr_idx, 1408 Node *val, 1409 BasicType bt, 1410 bool use_precise) { 1411 BarrierSet* bs = Universe::heap()->barrier_set(); 1412 set_control(ctl); 1413 switch (bs->kind()) { 1414 case BarrierSet::G1SATBCT: 1415 case BarrierSet::G1SATBCTLogging: 1416 g1_write_barrier_post(store, obj, adr, adr_idx, val, bt, use_precise); 1417 break; 1418 1419 case BarrierSet::CardTableModRef: 1420 case BarrierSet::CardTableExtension: 1421 write_barrier_post(store, obj, adr, val, use_precise); 1422 break; 1423 1424 case BarrierSet::ModRef: 1425 break; 1426 1427 case BarrierSet::Other: 1428 default : 1429 ShouldNotReachHere(); 1430 1431 } 1432 } 1433 1434 Node* GraphKit::store_oop_to_object(Node* ctl, 1435 Node* obj, 1436 Node* adr, 1437 const TypePtr* adr_type, 1438 Node *val, 1439 const Type* val_type, 1440 BasicType bt) { 1441 uint adr_idx = C->get_alias_index(adr_type); 1442 Node* store; 1443 pre_barrier(ctl, obj, adr, adr_idx, val, val_type, bt); 1444 store = store_to_memory(control(), adr, val, bt, adr_idx); 1445 post_barrier(control(), store, obj, adr, adr_idx, val, bt, false); 1446 return store; 1447 } 1448 1449 Node* GraphKit::store_oop_to_array(Node* ctl, 1450 Node* obj, 1451 Node* adr, 1452 const TypePtr* adr_type, 1453 Node *val, 1454 const Type* val_type, 1455 BasicType bt) { 1456 uint adr_idx = C->get_alias_index(adr_type); 1457 Node* store; 1458 pre_barrier(ctl, obj, adr, adr_idx, val, val_type, bt); 1459 store = store_to_memory(control(), adr, val, bt, adr_idx); 1460 post_barrier(control(), store, obj, adr, adr_idx, val, bt, true); 1461 return store; 1462 } 1463 1464 Node* GraphKit::store_oop_to_unknown(Node* ctl, 1465 Node* obj, 1466 Node* adr, 1467 const TypePtr* adr_type, 1468 Node *val, 1469 const Type* val_type, 1470 BasicType bt) { 1471 uint adr_idx = C->get_alias_index(adr_type); 1472 Node* store; 1473 pre_barrier(ctl, obj, adr, adr_idx, val, val_type, bt); 1474 store = store_to_memory(control(), adr, val, bt, adr_idx); 1475 post_barrier(control(), store, obj, adr, adr_idx, val, bt, true); 1476 return store; 1477 } 1478 1479 1480 //-------------------------array_element_address------------------------- 1481 Node* GraphKit::array_element_address(Node* ary, Node* idx, BasicType elembt, 1482 const TypeInt* sizetype) { 1483 uint shift = exact_log2(type2aelembytes(elembt)); 1484 uint header = arrayOopDesc::base_offset_in_bytes(elembt); 1485 1486 // short-circuit a common case (saves lots of confusing waste motion) 1487 jint idx_con = find_int_con(idx, -1); 1488 if (idx_con >= 0) { 1489 intptr_t offset = header + ((intptr_t)idx_con << shift); 1490 return basic_plus_adr(ary, offset); 1491 } 1492 1493 // must be correct type for alignment purposes 1494 Node* base = basic_plus_adr(ary, header); 1495 #ifdef _LP64 1496 // The scaled index operand to AddP must be a clean 64-bit value. 1497 // Java allows a 32-bit int to be incremented to a negative 1498 // value, which appears in a 64-bit register as a large 1499 // positive number. Using that large positive number as an 1500 // operand in pointer arithmetic has bad consequences. 1501 // On the other hand, 32-bit overflow is rare, and the possibility 1502 // can often be excluded, if we annotate the ConvI2L node with 1503 // a type assertion that its value is known to be a small positive 1504 // number. (The prior range check has ensured this.) 1505 // This assertion is used by ConvI2LNode::Ideal. 1506 int index_max = max_jint - 1; // array size is max_jint, index is one less 1507 if (sizetype != NULL) index_max = sizetype->_hi - 1; 1508 const TypeLong* lidxtype = TypeLong::make(CONST64(0), index_max, Type::WidenMax); 1509 idx = _gvn.transform( new (C, 2) ConvI2LNode(idx, lidxtype) ); 1510 #endif 1511 Node* scale = _gvn.transform( new (C, 3) LShiftXNode(idx, intcon(shift)) ); 1512 return basic_plus_adr(ary, base, scale); 1513 } 1514 1515 //-------------------------load_array_element------------------------- 1516 Node* GraphKit::load_array_element(Node* ctl, Node* ary, Node* idx, const TypeAryPtr* arytype) { 1517 const Type* elemtype = arytype->elem(); 1518 BasicType elembt = elemtype->array_element_basic_type(); 1519 Node* adr = array_element_address(ary, idx, elembt, arytype->size()); 1520 Node* ld = make_load(ctl, adr, elemtype, elembt, arytype); 1521 return ld; 1522 } 1523 1524 //-------------------------set_arguments_for_java_call------------------------- 1525 // Arguments (pre-popped from the stack) are taken from the JVMS. 1526 void GraphKit::set_arguments_for_java_call(CallJavaNode* call) { 1527 // Add the call arguments: 1528 uint nargs = call->method()->arg_size(); 1529 for (uint i = 0; i < nargs; i++) { 1530 Node* arg = argument(i); 1531 call->init_req(i + TypeFunc::Parms, arg); 1532 } 1533 } 1534 1535 //---------------------------set_edges_for_java_call--------------------------- 1536 // Connect a newly created call into the current JVMS. 1537 // A return value node (if any) is returned from set_edges_for_java_call. 1538 void GraphKit::set_edges_for_java_call(CallJavaNode* call, bool must_throw) { 1539 1540 // Add the predefined inputs: 1541 call->init_req( TypeFunc::Control, control() ); 1542 call->init_req( TypeFunc::I_O , i_o() ); 1543 call->init_req( TypeFunc::Memory , reset_memory() ); 1544 call->init_req( TypeFunc::FramePtr, frameptr() ); 1545 call->init_req( TypeFunc::ReturnAdr, top() ); 1546 1547 add_safepoint_edges(call, must_throw); 1548 1549 Node* xcall = _gvn.transform(call); 1550 1551 if (xcall == top()) { 1552 set_control(top()); 1553 return; 1554 } 1555 assert(xcall == call, "call identity is stable"); 1556 1557 // Re-use the current map to produce the result. 1558 1559 set_control(_gvn.transform(new (C, 1) ProjNode(call, TypeFunc::Control))); 1560 set_i_o( _gvn.transform(new (C, 1) ProjNode(call, TypeFunc::I_O ))); 1561 set_all_memory_call(xcall); 1562 1563 //return xcall; // no need, caller already has it 1564 } 1565 1566 Node* GraphKit::set_results_for_java_call(CallJavaNode* call) { 1567 if (stopped()) return top(); // maybe the call folded up? 1568 1569 // Capture the return value, if any. 1570 Node* ret; 1571 if (call->method() == NULL || 1572 call->method()->return_type()->basic_type() == T_VOID) 1573 ret = top(); 1574 else ret = _gvn.transform(new (C, 1) ProjNode(call, TypeFunc::Parms)); 1575 1576 // Note: Since any out-of-line call can produce an exception, 1577 // we always insert an I_O projection from the call into the result. 1578 1579 make_slow_call_ex(call, env()->Throwable_klass(), false); 1580 1581 return ret; 1582 } 1583 1584 //--------------------set_predefined_input_for_runtime_call-------------------- 1585 // Reading and setting the memory state is way conservative here. 1586 // The real problem is that I am not doing real Type analysis on memory, 1587 // so I cannot distinguish card mark stores from other stores. Across a GC 1588 // point the Store Barrier and the card mark memory has to agree. I cannot 1589 // have a card mark store and its barrier split across the GC point from 1590 // either above or below. Here I get that to happen by reading ALL of memory. 1591 // A better answer would be to separate out card marks from other memory. 1592 // For now, return the input memory state, so that it can be reused 1593 // after the call, if this call has restricted memory effects. 1594 Node* GraphKit::set_predefined_input_for_runtime_call(SafePointNode* call) { 1595 // Set fixed predefined input arguments 1596 Node* memory = reset_memory(); 1597 call->init_req( TypeFunc::Control, control() ); 1598 call->init_req( TypeFunc::I_O, top() ); // does no i/o 1599 call->init_req( TypeFunc::Memory, memory ); // may gc ptrs 1600 call->init_req( TypeFunc::FramePtr, frameptr() ); 1601 call->init_req( TypeFunc::ReturnAdr, top() ); 1602 return memory; 1603 } 1604 1605 //-------------------set_predefined_output_for_runtime_call-------------------- 1606 // Set control and memory (not i_o) from the call. 1607 // If keep_mem is not NULL, use it for the output state, 1608 // except for the RawPtr output of the call, if hook_mem is TypeRawPtr::BOTTOM. 1609 // If hook_mem is NULL, this call produces no memory effects at all. 1610 // If hook_mem is a Java-visible memory slice (such as arraycopy operands), 1611 // then only that memory slice is taken from the call. 1612 // In the last case, we must put an appropriate memory barrier before 1613 // the call, so as to create the correct anti-dependencies on loads 1614 // preceding the call. 1615 void GraphKit::set_predefined_output_for_runtime_call(Node* call, 1616 Node* keep_mem, 1617 const TypePtr* hook_mem) { 1618 // no i/o 1619 set_control(_gvn.transform( new (C, 1) ProjNode(call,TypeFunc::Control) )); 1620 if (keep_mem) { 1621 // First clone the existing memory state 1622 set_all_memory(keep_mem); 1623 if (hook_mem != NULL) { 1624 // Make memory for the call 1625 Node* mem = _gvn.transform( new (C, 1) ProjNode(call, TypeFunc::Memory) ); 1626 // Set the RawPtr memory state only. This covers all the heap top/GC stuff 1627 // We also use hook_mem to extract specific effects from arraycopy stubs. 1628 set_memory(mem, hook_mem); 1629 } 1630 // ...else the call has NO memory effects. 1631 1632 // Make sure the call advertises its memory effects precisely. 1633 // This lets us build accurate anti-dependences in gcm.cpp. 1634 assert(C->alias_type(call->adr_type()) == C->alias_type(hook_mem), 1635 "call node must be constructed correctly"); 1636 } else { 1637 assert(hook_mem == NULL, ""); 1638 // This is not a "slow path" call; all memory comes from the call. 1639 set_all_memory_call(call); 1640 } 1641 } 1642 1643 //------------------------------increment_counter------------------------------ 1644 // for statistics: increment a VM counter by 1 1645 1646 void GraphKit::increment_counter(address counter_addr) { 1647 Node* adr1 = makecon(TypeRawPtr::make(counter_addr)); 1648 increment_counter(adr1); 1649 } 1650 1651 void GraphKit::increment_counter(Node* counter_addr) { 1652 int adr_type = Compile::AliasIdxRaw; 1653 Node* cnt = make_load(NULL, counter_addr, TypeInt::INT, T_INT, adr_type); 1654 Node* incr = _gvn.transform(new (C, 3) AddINode(cnt, _gvn.intcon(1))); 1655 store_to_memory( NULL, counter_addr, incr, T_INT, adr_type ); 1656 } 1657 1658 1659 //------------------------------uncommon_trap---------------------------------- 1660 // Bail out to the interpreter in mid-method. Implemented by calling the 1661 // uncommon_trap blob. This helper function inserts a runtime call with the 1662 // right debug info. 1663 void GraphKit::uncommon_trap(int trap_request, 1664 ciKlass* klass, const char* comment, 1665 bool must_throw, 1666 bool keep_exact_action) { 1667 if (failing()) stop(); 1668 if (stopped()) return; // trap reachable? 1669 1670 // Note: If ProfileTraps is true, and if a deopt. actually 1671 // occurs here, the runtime will make sure an MDO exists. There is 1672 // no need to call method()->build_method_data() at this point. 1673 1674 #ifdef ASSERT 1675 if (!must_throw) { 1676 // Make sure the stack has at least enough depth to execute 1677 // the current bytecode. 1678 int inputs, ignore; 1679 if (compute_stack_effects(inputs, ignore)) { 1680 assert(sp() >= inputs, "must have enough JVMS stack to execute"); 1681 // It is a frequent error in library_call.cpp to issue an 1682 // uncommon trap with the _sp value already popped. 1683 } 1684 } 1685 #endif 1686 1687 Deoptimization::DeoptReason reason = Deoptimization::trap_request_reason(trap_request); 1688 Deoptimization::DeoptAction action = Deoptimization::trap_request_action(trap_request); 1689 1690 switch (action) { 1691 case Deoptimization::Action_maybe_recompile: 1692 case Deoptimization::Action_reinterpret: 1693 // Temporary fix for 6529811 to allow virtual calls to be sure they 1694 // get the chance to go from mono->bi->mega 1695 if (!keep_exact_action && 1696 Deoptimization::trap_request_index(trap_request) < 0 && 1697 too_many_recompiles(reason)) { 1698 // This BCI is causing too many recompilations. 1699 action = Deoptimization::Action_none; 1700 trap_request = Deoptimization::make_trap_request(reason, action); 1701 } else { 1702 C->set_trap_can_recompile(true); 1703 } 1704 break; 1705 case Deoptimization::Action_make_not_entrant: 1706 C->set_trap_can_recompile(true); 1707 break; 1708 #ifdef ASSERT 1709 case Deoptimization::Action_none: 1710 case Deoptimization::Action_make_not_compilable: 1711 break; 1712 default: 1713 assert(false, "bad action"); 1714 #endif 1715 } 1716 1717 if (TraceOptoParse) { 1718 char buf[100]; 1719 tty->print_cr("Uncommon trap %s at bci:%d", 1720 Deoptimization::format_trap_request(buf, sizeof(buf), 1721 trap_request), bci()); 1722 } 1723 1724 CompileLog* log = C->log(); 1725 if (log != NULL) { 1726 int kid = (klass == NULL)? -1: log->identify(klass); 1727 log->begin_elem("uncommon_trap bci='%d'", bci()); 1728 char buf[100]; 1729 log->print(" %s", Deoptimization::format_trap_request(buf, sizeof(buf), 1730 trap_request)); 1731 if (kid >= 0) log->print(" klass='%d'", kid); 1732 if (comment != NULL) log->print(" comment='%s'", comment); 1733 log->end_elem(); 1734 } 1735 1736 // Make sure any guarding test views this path as very unlikely 1737 Node *i0 = control()->in(0); 1738 if (i0 != NULL && i0->is_If()) { // Found a guarding if test? 1739 IfNode *iff = i0->as_If(); 1740 float f = iff->_prob; // Get prob 1741 if (control()->Opcode() == Op_IfTrue) { 1742 if (f > PROB_UNLIKELY_MAG(4)) 1743 iff->_prob = PROB_MIN; 1744 } else { 1745 if (f < PROB_LIKELY_MAG(4)) 1746 iff->_prob = PROB_MAX; 1747 } 1748 } 1749 1750 // Clear out dead values from the debug info. 1751 kill_dead_locals(); 1752 1753 // Now insert the uncommon trap subroutine call 1754 address call_addr = SharedRuntime::uncommon_trap_blob()->instructions_begin(); 1755 const TypePtr* no_memory_effects = NULL; 1756 // Pass the index of the class to be loaded 1757 Node* call = make_runtime_call(RC_NO_LEAF | RC_UNCOMMON | 1758 (must_throw ? RC_MUST_THROW : 0), 1759 OptoRuntime::uncommon_trap_Type(), 1760 call_addr, "uncommon_trap", no_memory_effects, 1761 intcon(trap_request)); 1762 assert(call->as_CallStaticJava()->uncommon_trap_request() == trap_request, 1763 "must extract request correctly from the graph"); 1764 assert(trap_request != 0, "zero value reserved by uncommon_trap_request"); 1765 1766 call->set_req(TypeFunc::ReturnAdr, returnadr()); 1767 // The debug info is the only real input to this call. 1768 1769 // Halt-and-catch fire here. The above call should never return! 1770 HaltNode* halt = new(C, TypeFunc::Parms) HaltNode(control(), frameptr()); 1771 _gvn.set_type_bottom(halt); 1772 root()->add_req(halt); 1773 1774 stop_and_kill_map(); 1775 } 1776 1777 1778 //--------------------------just_allocated_object------------------------------ 1779 // Report the object that was just allocated. 1780 // It must be the case that there are no intervening safepoints. 1781 // We use this to determine if an object is so "fresh" that 1782 // it does not require card marks. 1783 Node* GraphKit::just_allocated_object(Node* current_control) { 1784 if (C->recent_alloc_ctl() == current_control) 1785 return C->recent_alloc_obj(); 1786 return NULL; 1787 } 1788 1789 1790 //------------------------------store_barrier---------------------------------- 1791 // Insert a write-barrier store. This is to let generational GC work; we have 1792 // to flag all oop-stores before the next GC point. 1793 void GraphKit::write_barrier_post(Node* oop_store, Node* obj, Node* adr, 1794 Node* val, bool use_precise) { 1795 // No store check needed if we're storing a NULL or an old object 1796 // (latter case is probably a string constant). The concurrent 1797 // mark sweep garbage collector, however, needs to have all nonNull 1798 // oop updates flagged via card-marks. 1799 if (val != NULL && val->is_Con()) { 1800 // must be either an oop or NULL 1801 const Type* t = val->bottom_type(); 1802 if (t == TypePtr::NULL_PTR || t == Type::TOP) 1803 // stores of null never (?) need barriers 1804 return; 1805 ciObject* con = t->is_oopptr()->const_oop(); 1806 if (con != NULL 1807 && con->is_perm() 1808 && Universe::heap()->can_elide_permanent_oop_store_barriers()) 1809 // no store barrier needed, because no old-to-new ref created 1810 return; 1811 } 1812 1813 if (use_ReduceInitialCardMarks() 1814 && obj == just_allocated_object(control())) { 1815 // We can skip marks on a freshly-allocated object. 1816 // Keep this code in sync with do_eager_card_mark in runtime.cpp. 1817 // That routine eagerly marks the occasional object which is produced 1818 // by the slow path, so that we don't have to do it here. 1819 return; 1820 } 1821 1822 if (!use_precise) { 1823 // All card marks for a (non-array) instance are in one place: 1824 adr = obj; 1825 } 1826 // (Else it's an array (or unknown), and we want more precise card marks.) 1827 assert(adr != NULL, ""); 1828 1829 // Get the alias_index for raw card-mark memory 1830 int adr_type = Compile::AliasIdxRaw; 1831 // Convert the pointer to an int prior to doing math on it 1832 Node* cast = _gvn.transform(new (C, 2) CastP2XNode(control(), adr)); 1833 // Divide by card size 1834 assert(Universe::heap()->barrier_set()->kind() == BarrierSet::CardTableModRef, 1835 "Only one we handle so far."); 1836 CardTableModRefBS* ct = 1837 (CardTableModRefBS*)(Universe::heap()->barrier_set()); 1838 Node *b = _gvn.transform(new (C, 3) URShiftXNode( cast, _gvn.intcon(CardTableModRefBS::card_shift) )); 1839 // We store into a byte array, so do not bother to left-shift by zero 1840 Node *c = byte_map_base_node(); 1841 // Combine 1842 Node *sb_ctl = control(); 1843 Node *sb_adr = _gvn.transform(new (C, 4) AddPNode( top()/*no base ptr*/, c, b )); 1844 Node *sb_val = _gvn.intcon(0); 1845 // Smash zero into card 1846 if( !UseConcMarkSweepGC ) { 1847 BasicType bt = T_BYTE; 1848 store_to_memory(sb_ctl, sb_adr, sb_val, bt, adr_type); 1849 } else { 1850 // Specialized path for CM store barrier 1851 cms_card_mark( sb_ctl, sb_adr, sb_val, oop_store); 1852 } 1853 } 1854 1855 // Specialized path for CMS store barrier 1856 void GraphKit::cms_card_mark(Node* ctl, Node* adr, Node* val, Node *oop_store) { 1857 BasicType bt = T_BYTE; 1858 int adr_idx = Compile::AliasIdxRaw; 1859 Node* mem = memory(adr_idx); 1860 1861 // The type input is NULL in PRODUCT builds 1862 const TypePtr* type = NULL; 1863 debug_only(type = C->get_adr_type(adr_idx)); 1864 1865 // Add required edge to oop_store, optimizer does not support precedence edges. 1866 // Convert required edge to precedence edge before allocation. 1867 Node *store = _gvn.transform( new (C, 5) StoreCMNode(ctl, mem, adr, type, val, oop_store) ); 1868 set_memory(store, adr_idx); 1869 1870 // For CMS, back-to-back card-marks can only remove the first one 1871 // and this requires DU info. Push on worklist for optimizer. 1872 if (mem->req() > MemNode::Address && adr == mem->in(MemNode::Address)) 1873 record_for_igvn(store); 1874 } 1875 1876 1877 void GraphKit::round_double_arguments(ciMethod* dest_method) { 1878 // (Note: TypeFunc::make has a cache that makes this fast.) 1879 const TypeFunc* tf = TypeFunc::make(dest_method); 1880 int nargs = tf->_domain->_cnt - TypeFunc::Parms; 1881 for (int j = 0; j < nargs; j++) { 1882 const Type *targ = tf->_domain->field_at(j + TypeFunc::Parms); 1883 if( targ->basic_type() == T_DOUBLE ) { 1884 // If any parameters are doubles, they must be rounded before 1885 // the call, dstore_rounding does gvn.transform 1886 Node *arg = argument(j); 1887 arg = dstore_rounding(arg); 1888 set_argument(j, arg); 1889 } 1890 } 1891 } 1892 1893 void GraphKit::round_double_result(ciMethod* dest_method) { 1894 // A non-strict method may return a double value which has an extended 1895 // exponent, but this must not be visible in a caller which is 'strict' 1896 // If a strict caller invokes a non-strict callee, round a double result 1897 1898 BasicType result_type = dest_method->return_type()->basic_type(); 1899 assert( method() != NULL, "must have caller context"); 1900 if( result_type == T_DOUBLE && method()->is_strict() && !dest_method->is_strict() ) { 1901 // Destination method's return value is on top of stack 1902 // dstore_rounding() does gvn.transform 1903 Node *result = pop_pair(); 1904 result = dstore_rounding(result); 1905 push_pair(result); 1906 } 1907 } 1908 1909 // rounding for strict float precision conformance 1910 Node* GraphKit::precision_rounding(Node* n) { 1911 return UseStrictFP && _method->flags().is_strict() 1912 && UseSSE == 0 && Matcher::strict_fp_requires_explicit_rounding 1913 ? _gvn.transform( new (C, 2) RoundFloatNode(0, n) ) 1914 : n; 1915 } 1916 1917 // rounding for strict double precision conformance 1918 Node* GraphKit::dprecision_rounding(Node *n) { 1919 return UseStrictFP && _method->flags().is_strict() 1920 && UseSSE <= 1 && Matcher::strict_fp_requires_explicit_rounding 1921 ? _gvn.transform( new (C, 2) RoundDoubleNode(0, n) ) 1922 : n; 1923 } 1924 1925 // rounding for non-strict double stores 1926 Node* GraphKit::dstore_rounding(Node* n) { 1927 return Matcher::strict_fp_requires_explicit_rounding 1928 && UseSSE <= 1 1929 ? _gvn.transform( new (C, 2) RoundDoubleNode(0, n) ) 1930 : n; 1931 } 1932 1933 //============================================================================= 1934 // Generate a fast path/slow path idiom. Graph looks like: 1935 // [foo] indicates that 'foo' is a parameter 1936 // 1937 // [in] NULL 1938 // \ / 1939 // CmpP 1940 // Bool ne 1941 // If 1942 // / \ 1943 // True False-<2> 1944 // / | 1945 // / cast_not_null 1946 // Load | | ^ 1947 // [fast_test] | | 1948 // gvn to opt_test | | 1949 // / \ | <1> 1950 // True False | 1951 // | \\ | 1952 // [slow_call] \[fast_result] 1953 // Ctl Val \ \ 1954 // | \ \ 1955 // Catch <1> \ \ 1956 // / \ ^ \ \ 1957 // Ex No_Ex | \ \ 1958 // | \ \ | \ <2> \ 1959 // ... \ [slow_res] | | \ [null_result] 1960 // \ \--+--+--- | | 1961 // \ | / \ | / 1962 // --------Region Phi 1963 // 1964 //============================================================================= 1965 // Code is structured as a series of driver functions all called 'do_XXX' that 1966 // call a set of helper functions. Helper functions first, then drivers. 1967 1968 //------------------------------null_check_oop--------------------------------- 1969 // Null check oop. Set null-path control into Region in slot 3. 1970 // Make a cast-not-nullness use the other not-null control. Return cast. 1971 Node* GraphKit::null_check_oop(Node* value, Node* *null_control, 1972 bool never_see_null) { 1973 // Initial NULL check taken path 1974 (*null_control) = top(); 1975 Node* cast = null_check_common(value, T_OBJECT, false, null_control); 1976 1977 // Generate uncommon_trap: 1978 if (never_see_null && (*null_control) != top()) { 1979 // If we see an unexpected null at a check-cast we record it and force a 1980 // recompile; the offending check-cast will be compiled to handle NULLs. 1981 // If we see more than one offending BCI, then all checkcasts in the 1982 // method will be compiled to handle NULLs. 1983 PreserveJVMState pjvms(this); 1984 set_control(*null_control); 1985 replace_in_map(value, null()); 1986 uncommon_trap(Deoptimization::Reason_null_check, 1987 Deoptimization::Action_make_not_entrant); 1988 (*null_control) = top(); // NULL path is dead 1989 } 1990 1991 // Cast away null-ness on the result 1992 return cast; 1993 } 1994 1995 //------------------------------opt_iff---------------------------------------- 1996 // Optimize the fast-check IfNode. Set the fast-path region slot 2. 1997 // Return slow-path control. 1998 Node* GraphKit::opt_iff(Node* region, Node* iff) { 1999 IfNode *opt_iff = _gvn.transform(iff)->as_If(); 2000 2001 // Fast path taken; set region slot 2 2002 Node *fast_taken = _gvn.transform( new (C, 1) IfFalseNode(opt_iff) ); 2003 region->init_req(2,fast_taken); // Capture fast-control 2004 2005 // Fast path not-taken, i.e. slow path 2006 Node *slow_taken = _gvn.transform( new (C, 1) IfTrueNode(opt_iff) ); 2007 return slow_taken; 2008 } 2009 2010 //-----------------------------make_runtime_call------------------------------- 2011 Node* GraphKit::make_runtime_call(int flags, 2012 const TypeFunc* call_type, address call_addr, 2013 const char* call_name, 2014 const TypePtr* adr_type, 2015 // The following parms are all optional. 2016 // The first NULL ends the list. 2017 Node* parm0, Node* parm1, 2018 Node* parm2, Node* parm3, 2019 Node* parm4, Node* parm5, 2020 Node* parm6, Node* parm7) { 2021 // Slow-path call 2022 int size = call_type->domain()->cnt(); 2023 bool is_leaf = !(flags & RC_NO_LEAF); 2024 bool has_io = (!is_leaf && !(flags & RC_NO_IO)); 2025 if (call_name == NULL) { 2026 assert(!is_leaf, "must supply name for leaf"); 2027 call_name = OptoRuntime::stub_name(call_addr); 2028 } 2029 CallNode* call; 2030 if (!is_leaf) { 2031 call = new(C, size) CallStaticJavaNode(call_type, call_addr, call_name, 2032 bci(), adr_type); 2033 } else if (flags & RC_NO_FP) { 2034 call = new(C, size) CallLeafNoFPNode(call_type, call_addr, call_name, adr_type); 2035 } else { 2036 call = new(C, size) CallLeafNode(call_type, call_addr, call_name, adr_type); 2037 } 2038 2039 // The following is similar to set_edges_for_java_call, 2040 // except that the memory effects of the call are restricted to AliasIdxRaw. 2041 2042 // Slow path call has no side-effects, uses few values 2043 bool wide_in = !(flags & RC_NARROW_MEM); 2044 bool wide_out = (C->get_alias_index(adr_type) == Compile::AliasIdxBot); 2045 2046 Node* prev_mem = NULL; 2047 if (wide_in) { 2048 prev_mem = set_predefined_input_for_runtime_call(call); 2049 } else { 2050 assert(!wide_out, "narrow in => narrow out"); 2051 Node* narrow_mem = memory(adr_type); 2052 prev_mem = reset_memory(); 2053 map()->set_memory(narrow_mem); 2054 set_predefined_input_for_runtime_call(call); 2055 } 2056 2057 // Hook each parm in order. Stop looking at the first NULL. 2058 if (parm0 != NULL) { call->init_req(TypeFunc::Parms+0, parm0); 2059 if (parm1 != NULL) { call->init_req(TypeFunc::Parms+1, parm1); 2060 if (parm2 != NULL) { call->init_req(TypeFunc::Parms+2, parm2); 2061 if (parm3 != NULL) { call->init_req(TypeFunc::Parms+3, parm3); 2062 if (parm4 != NULL) { call->init_req(TypeFunc::Parms+4, parm4); 2063 if (parm5 != NULL) { call->init_req(TypeFunc::Parms+5, parm5); 2064 if (parm6 != NULL) { call->init_req(TypeFunc::Parms+6, parm6); 2065 if (parm7 != NULL) { call->init_req(TypeFunc::Parms+7, parm7); 2066 /* close each nested if ===> */ } } } } } } } } 2067 assert(call->in(call->req()-1) != NULL, "must initialize all parms"); 2068 2069 if (!is_leaf) { 2070 // Non-leaves can block and take safepoints: 2071 add_safepoint_edges(call, ((flags & RC_MUST_THROW) != 0)); 2072 } 2073 // Non-leaves can throw exceptions: 2074 if (has_io) { 2075 call->set_req(TypeFunc::I_O, i_o()); 2076 } 2077 2078 if (flags & RC_UNCOMMON) { 2079 // Set the count to a tiny probability. Cf. Estimate_Block_Frequency. 2080 // (An "if" probability corresponds roughly to an unconditional count. 2081 // Sort of.) 2082 call->set_cnt(PROB_UNLIKELY_MAG(4)); 2083 } 2084 2085 Node* c = _gvn.transform(call); 2086 assert(c == call, "cannot disappear"); 2087 2088 if (wide_out) { 2089 // Slow path call has full side-effects. 2090 set_predefined_output_for_runtime_call(call); 2091 } else { 2092 // Slow path call has few side-effects, and/or sets few values. 2093 set_predefined_output_for_runtime_call(call, prev_mem, adr_type); 2094 } 2095 2096 if (has_io) { 2097 set_i_o(_gvn.transform(new (C, 1) ProjNode(call, TypeFunc::I_O))); 2098 } 2099 return call; 2100 2101 } 2102 2103 //------------------------------merge_memory----------------------------------- 2104 // Merge memory from one path into the current memory state. 2105 void GraphKit::merge_memory(Node* new_mem, Node* region, int new_path) { 2106 for (MergeMemStream mms(merged_memory(), new_mem->as_MergeMem()); mms.next_non_empty2(); ) { 2107 Node* old_slice = mms.force_memory(); 2108 Node* new_slice = mms.memory2(); 2109 if (old_slice != new_slice) { 2110 PhiNode* phi; 2111 if (new_slice->is_Phi() && new_slice->as_Phi()->region() == region) { 2112 phi = new_slice->as_Phi(); 2113 #ifdef ASSERT 2114 if (old_slice->is_Phi() && old_slice->as_Phi()->region() == region) 2115 old_slice = old_slice->in(new_path); 2116 // Caller is responsible for ensuring that any pre-existing 2117 // phis are already aware of old memory. 2118 int old_path = (new_path > 1) ? 1 : 2; // choose old_path != new_path 2119 assert(phi->in(old_path) == old_slice, "pre-existing phis OK"); 2120 #endif 2121 mms.set_memory(phi); 2122 } else { 2123 phi = PhiNode::make(region, old_slice, Type::MEMORY, mms.adr_type(C)); 2124 _gvn.set_type(phi, Type::MEMORY); 2125 phi->set_req(new_path, new_slice); 2126 mms.set_memory(_gvn.transform(phi)); // assume it is complete 2127 } 2128 } 2129 } 2130 } 2131 2132 //------------------------------make_slow_call_ex------------------------------ 2133 // Make the exception handler hookups for the slow call 2134 void GraphKit::make_slow_call_ex(Node* call, ciInstanceKlass* ex_klass, bool separate_io_proj) { 2135 if (stopped()) return; 2136 2137 // Make a catch node with just two handlers: fall-through and catch-all 2138 Node* i_o = _gvn.transform( new (C, 1) ProjNode(call, TypeFunc::I_O, separate_io_proj) ); 2139 Node* catc = _gvn.transform( new (C, 2) CatchNode(control(), i_o, 2) ); 2140 Node* norm = _gvn.transform( new (C, 1) CatchProjNode(catc, CatchProjNode::fall_through_index, CatchProjNode::no_handler_bci) ); 2141 Node* excp = _gvn.transform( new (C, 1) CatchProjNode(catc, CatchProjNode::catch_all_index, CatchProjNode::no_handler_bci) ); 2142 2143 { PreserveJVMState pjvms(this); 2144 set_control(excp); 2145 set_i_o(i_o); 2146 2147 if (excp != top()) { 2148 // Create an exception state also. 2149 // Use an exact type if the caller has specified a specific exception. 2150 const Type* ex_type = TypeOopPtr::make_from_klass_unique(ex_klass)->cast_to_ptr_type(TypePtr::NotNull); 2151 Node* ex_oop = new (C, 2) CreateExNode(ex_type, control(), i_o); 2152 add_exception_state(make_exception_state(_gvn.transform(ex_oop))); 2153 } 2154 } 2155 2156 // Get the no-exception control from the CatchNode. 2157 set_control(norm); 2158 } 2159 2160 2161 //-------------------------------gen_subtype_check----------------------------- 2162 // Generate a subtyping check. Takes as input the subtype and supertype. 2163 // Returns 2 values: sets the default control() to the true path and returns 2164 // the false path. Only reads invariant memory; sets no (visible) memory. 2165 // The PartialSubtypeCheckNode sets the hidden 1-word cache in the encoding 2166 // but that's not exposed to the optimizer. This call also doesn't take in an 2167 // Object; if you wish to check an Object you need to load the Object's class 2168 // prior to coming here. 2169 Node* GraphKit::gen_subtype_check(Node* subklass, Node* superklass) { 2170 // Fast check for identical types, perhaps identical constants. 2171 // The types can even be identical non-constants, in cases 2172 // involving Array.newInstance, Object.clone, etc. 2173 if (subklass == superklass) 2174 return top(); // false path is dead; no test needed. 2175 2176 if (_gvn.type(superklass)->singleton()) { 2177 ciKlass* superk = _gvn.type(superklass)->is_klassptr()->klass(); 2178 ciKlass* subk = _gvn.type(subklass)->is_klassptr()->klass(); 2179 2180 // In the common case of an exact superklass, try to fold up the 2181 // test before generating code. You may ask, why not just generate 2182 // the code and then let it fold up? The answer is that the generated 2183 // code will necessarily include null checks, which do not always 2184 // completely fold away. If they are also needless, then they turn 2185 // into a performance loss. Example: 2186 // Foo[] fa = blah(); Foo x = fa[0]; fa[1] = x; 2187 // Here, the type of 'fa' is often exact, so the store check 2188 // of fa[1]=x will fold up, without testing the nullness of x. 2189 switch (static_subtype_check(superk, subk)) { 2190 case SSC_always_false: 2191 { 2192 Node* always_fail = control(); 2193 set_control(top()); 2194 return always_fail; 2195 } 2196 case SSC_always_true: 2197 return top(); 2198 case SSC_easy_test: 2199 { 2200 // Just do a direct pointer compare and be done. 2201 Node* cmp = _gvn.transform( new(C, 3) CmpPNode(subklass, superklass) ); 2202 Node* bol = _gvn.transform( new(C, 2) BoolNode(cmp, BoolTest::eq) ); 2203 IfNode* iff = create_and_xform_if(control(), bol, PROB_STATIC_FREQUENT, COUNT_UNKNOWN); 2204 set_control( _gvn.transform( new(C, 1) IfTrueNode (iff) ) ); 2205 return _gvn.transform( new(C, 1) IfFalseNode(iff) ); 2206 } 2207 case SSC_full_test: 2208 break; 2209 default: 2210 ShouldNotReachHere(); 2211 } 2212 } 2213 2214 // %%% Possible further optimization: Even if the superklass is not exact, 2215 // if the subklass is the unique subtype of the superklass, the check 2216 // will always succeed. We could leave a dependency behind to ensure this. 2217 2218 // First load the super-klass's check-offset 2219 Node *p1 = basic_plus_adr( superklass, superklass, sizeof(oopDesc) + Klass::super_check_offset_offset_in_bytes() ); 2220 Node *chk_off = _gvn.transform( new (C, 3) LoadINode( NULL, memory(p1), p1, _gvn.type(p1)->is_ptr() ) ); 2221 int cacheoff_con = sizeof(oopDesc) + Klass::secondary_super_cache_offset_in_bytes(); 2222 bool might_be_cache = (find_int_con(chk_off, cacheoff_con) == cacheoff_con); 2223 2224 // Load from the sub-klass's super-class display list, or a 1-word cache of 2225 // the secondary superclass list, or a failing value with a sentinel offset 2226 // if the super-klass is an interface or exceptionally deep in the Java 2227 // hierarchy and we have to scan the secondary superclass list the hard way. 2228 // Worst-case type is a little odd: NULL is allowed as a result (usually 2229 // klass loads can never produce a NULL). 2230 Node *chk_off_X = ConvI2X(chk_off); 2231 Node *p2 = _gvn.transform( new (C, 4) AddPNode(subklass,subklass,chk_off_X) ); 2232 // For some types like interfaces the following loadKlass is from a 1-word 2233 // cache which is mutable so can't use immutable memory. Other 2234 // types load from the super-class display table which is immutable. 2235 Node *kmem = might_be_cache ? memory(p2) : immutable_memory(); 2236 Node *nkls = _gvn.transform( LoadKlassNode::make( _gvn, kmem, p2, _gvn.type(p2)->is_ptr(), TypeKlassPtr::OBJECT_OR_NULL ) ); 2237 2238 // Compile speed common case: ARE a subtype and we canNOT fail 2239 if( superklass == nkls ) 2240 return top(); // false path is dead; no test needed. 2241 2242 // See if we get an immediate positive hit. Happens roughly 83% of the 2243 // time. Test to see if the value loaded just previously from the subklass 2244 // is exactly the superklass. 2245 Node *cmp1 = _gvn.transform( new (C, 3) CmpPNode( superklass, nkls ) ); 2246 Node *bol1 = _gvn.transform( new (C, 2) BoolNode( cmp1, BoolTest::eq ) ); 2247 IfNode *iff1 = create_and_xform_if( control(), bol1, PROB_LIKELY(0.83f), COUNT_UNKNOWN ); 2248 Node *iftrue1 = _gvn.transform( new (C, 1) IfTrueNode ( iff1 ) ); 2249 set_control( _gvn.transform( new (C, 1) IfFalseNode( iff1 ) ) ); 2250 2251 // Compile speed common case: Check for being deterministic right now. If 2252 // chk_off is a constant and not equal to cacheoff then we are NOT a 2253 // subklass. In this case we need exactly the 1 test above and we can 2254 // return those results immediately. 2255 if (!might_be_cache) { 2256 Node* not_subtype_ctrl = control(); 2257 set_control(iftrue1); // We need exactly the 1 test above 2258 return not_subtype_ctrl; 2259 } 2260 2261 // Gather the various success & failures here 2262 RegionNode *r_ok_subtype = new (C, 4) RegionNode(4); 2263 record_for_igvn(r_ok_subtype); 2264 RegionNode *r_not_subtype = new (C, 3) RegionNode(3); 2265 record_for_igvn(r_not_subtype); 2266 2267 r_ok_subtype->init_req(1, iftrue1); 2268 2269 // Check for immediate negative hit. Happens roughly 11% of the time (which 2270 // is roughly 63% of the remaining cases). Test to see if the loaded 2271 // check-offset points into the subklass display list or the 1-element 2272 // cache. If it points to the display (and NOT the cache) and the display 2273 // missed then it's not a subtype. 2274 Node *cacheoff = _gvn.intcon(cacheoff_con); 2275 Node *cmp2 = _gvn.transform( new (C, 3) CmpINode( chk_off, cacheoff ) ); 2276 Node *bol2 = _gvn.transform( new (C, 2) BoolNode( cmp2, BoolTest::ne ) ); 2277 IfNode *iff2 = create_and_xform_if( control(), bol2, PROB_LIKELY(0.63f), COUNT_UNKNOWN ); 2278 r_not_subtype->init_req(1, _gvn.transform( new (C, 1) IfTrueNode (iff2) ) ); 2279 set_control( _gvn.transform( new (C, 1) IfFalseNode(iff2) ) ); 2280 2281 // Check for self. Very rare to get here, but it is taken 1/3 the time. 2282 // No performance impact (too rare) but allows sharing of secondary arrays 2283 // which has some footprint reduction. 2284 Node *cmp3 = _gvn.transform( new (C, 3) CmpPNode( subklass, superklass ) ); 2285 Node *bol3 = _gvn.transform( new (C, 2) BoolNode( cmp3, BoolTest::eq ) ); 2286 IfNode *iff3 = create_and_xform_if( control(), bol3, PROB_LIKELY(0.36f), COUNT_UNKNOWN ); 2287 r_ok_subtype->init_req(2, _gvn.transform( new (C, 1) IfTrueNode ( iff3 ) ) ); 2288 set_control( _gvn.transform( new (C, 1) IfFalseNode( iff3 ) ) ); 2289 2290 // -- Roads not taken here: -- 2291 // We could also have chosen to perform the self-check at the beginning 2292 // of this code sequence, as the assembler does. This would not pay off 2293 // the same way, since the optimizer, unlike the assembler, can perform 2294 // static type analysis to fold away many successful self-checks. 2295 // Non-foldable self checks work better here in second position, because 2296 // the initial primary superclass check subsumes a self-check for most 2297 // types. An exception would be a secondary type like array-of-interface, 2298 // which does not appear in its own primary supertype display. 2299 // Finally, we could have chosen to move the self-check into the 2300 // PartialSubtypeCheckNode, and from there out-of-line in a platform 2301 // dependent manner. But it is worthwhile to have the check here, 2302 // where it can be perhaps be optimized. The cost in code space is 2303 // small (register compare, branch). 2304 2305 // Now do a linear scan of the secondary super-klass array. Again, no real 2306 // performance impact (too rare) but it's gotta be done. 2307 // Since the code is rarely used, there is no penalty for moving it 2308 // out of line, and it can only improve I-cache density. 2309 // The decision to inline or out-of-line this final check is platform 2310 // dependent, and is found in the AD file definition of PartialSubtypeCheck. 2311 Node* psc = _gvn.transform( 2312 new (C, 3) PartialSubtypeCheckNode(control(), subklass, superklass) ); 2313 2314 Node *cmp4 = _gvn.transform( new (C, 3) CmpPNode( psc, null() ) ); 2315 Node *bol4 = _gvn.transform( new (C, 2) BoolNode( cmp4, BoolTest::ne ) ); 2316 IfNode *iff4 = create_and_xform_if( control(), bol4, PROB_FAIR, COUNT_UNKNOWN ); 2317 r_not_subtype->init_req(2, _gvn.transform( new (C, 1) IfTrueNode (iff4) ) ); 2318 r_ok_subtype ->init_req(3, _gvn.transform( new (C, 1) IfFalseNode(iff4) ) ); 2319 2320 // Return false path; set default control to true path. 2321 set_control( _gvn.transform(r_ok_subtype) ); 2322 return _gvn.transform(r_not_subtype); 2323 } 2324 2325 //----------------------------static_subtype_check----------------------------- 2326 // Shortcut important common cases when superklass is exact: 2327 // (0) superklass is java.lang.Object (can occur in reflective code) 2328 // (1) subklass is already limited to a subtype of superklass => always ok 2329 // (2) subklass does not overlap with superklass => always fail 2330 // (3) superklass has NO subtypes and we can check with a simple compare. 2331 int GraphKit::static_subtype_check(ciKlass* superk, ciKlass* subk) { 2332 if (StressReflectiveCode) { 2333 return SSC_full_test; // Let caller generate the general case. 2334 } 2335 2336 if (superk == env()->Object_klass()) { 2337 return SSC_always_true; // (0) this test cannot fail 2338 } 2339 2340 ciType* superelem = superk; 2341 if (superelem->is_array_klass()) 2342 superelem = superelem->as_array_klass()->base_element_type(); 2343 2344 if (!subk->is_interface()) { // cannot trust static interface types yet 2345 if (subk->is_subtype_of(superk)) { 2346 return SSC_always_true; // (1) false path dead; no dynamic test needed 2347 } 2348 if (!(superelem->is_klass() && superelem->as_klass()->is_interface()) && 2349 !superk->is_subtype_of(subk)) { 2350 return SSC_always_false; 2351 } 2352 } 2353 2354 // If casting to an instance klass, it must have no subtypes 2355 if (superk->is_interface()) { 2356 // Cannot trust interfaces yet. 2357 // %%% S.B. superk->nof_implementors() == 1 2358 } else if (superelem->is_instance_klass()) { 2359 ciInstanceKlass* ik = superelem->as_instance_klass(); 2360 if (!ik->has_subklass() && !ik->is_interface()) { 2361 if (!ik->is_final()) { 2362 // Add a dependency if there is a chance of a later subclass. 2363 C->dependencies()->assert_leaf_type(ik); 2364 } 2365 return SSC_easy_test; // (3) caller can do a simple ptr comparison 2366 } 2367 } else { 2368 // A primitive array type has no subtypes. 2369 return SSC_easy_test; // (3) caller can do a simple ptr comparison 2370 } 2371 2372 return SSC_full_test; 2373 } 2374 2375 // Profile-driven exact type check: 2376 Node* GraphKit::type_check_receiver(Node* receiver, ciKlass* klass, 2377 float prob, 2378 Node* *casted_receiver) { 2379 const TypeKlassPtr* tklass = TypeKlassPtr::make(klass); 2380 Node* recv_klass = load_object_klass(receiver); 2381 Node* want_klass = makecon(tklass); 2382 Node* cmp = _gvn.transform( new(C, 3) CmpPNode(recv_klass, want_klass) ); 2383 Node* bol = _gvn.transform( new(C, 2) BoolNode(cmp, BoolTest::eq) ); 2384 IfNode* iff = create_and_xform_if(control(), bol, prob, COUNT_UNKNOWN); 2385 set_control( _gvn.transform( new(C, 1) IfTrueNode (iff) )); 2386 Node* fail = _gvn.transform( new(C, 1) IfFalseNode(iff) ); 2387 2388 const TypeOopPtr* recv_xtype = tklass->as_instance_type(); 2389 assert(recv_xtype->klass_is_exact(), ""); 2390 2391 // Subsume downstream occurrences of receiver with a cast to 2392 // recv_xtype, since now we know what the type will be. 2393 Node* cast = new(C, 2) CheckCastPPNode(control(), receiver, recv_xtype); 2394 (*casted_receiver) = _gvn.transform(cast); 2395 // (User must make the replace_in_map call.) 2396 2397 return fail; 2398 } 2399 2400 2401 //-------------------------------gen_instanceof-------------------------------- 2402 // Generate an instance-of idiom. Used by both the instance-of bytecode 2403 // and the reflective instance-of call. 2404 Node* GraphKit::gen_instanceof( Node *subobj, Node* superklass ) { 2405 C->set_has_split_ifs(true); // Has chance for split-if optimization 2406 assert( !stopped(), "dead parse path should be checked in callers" ); 2407 assert(!TypePtr::NULL_PTR->higher_equal(_gvn.type(superklass)->is_klassptr()), 2408 "must check for not-null not-dead klass in callers"); 2409 2410 // Make the merge point 2411 enum { _obj_path = 1, _fail_path, _null_path, PATH_LIMIT }; 2412 RegionNode* region = new(C, PATH_LIMIT) RegionNode(PATH_LIMIT); 2413 Node* phi = new(C, PATH_LIMIT) PhiNode(region, TypeInt::BOOL); 2414 C->set_has_split_ifs(true); // Has chance for split-if optimization 2415 2416 // Null check; get casted pointer; set region slot 3 2417 Node* null_ctl = top(); 2418 Node* not_null_obj = null_check_oop(subobj, &null_ctl); 2419 2420 // If not_null_obj is dead, only null-path is taken 2421 if (stopped()) { // Doing instance-of on a NULL? 2422 set_control(null_ctl); 2423 return intcon(0); 2424 } 2425 region->init_req(_null_path, null_ctl); 2426 phi ->init_req(_null_path, intcon(0)); // Set null path value 2427 2428 // Load the object's klass 2429 Node* obj_klass = load_object_klass(not_null_obj); 2430 2431 // Generate the subtype check 2432 Node* not_subtype_ctrl = gen_subtype_check(obj_klass, superklass); 2433 2434 // Plug in the success path to the general merge in slot 1. 2435 region->init_req(_obj_path, control()); 2436 phi ->init_req(_obj_path, intcon(1)); 2437 2438 // Plug in the failing path to the general merge in slot 2. 2439 region->init_req(_fail_path, not_subtype_ctrl); 2440 phi ->init_req(_fail_path, intcon(0)); 2441 2442 // Return final merged results 2443 set_control( _gvn.transform(region) ); 2444 record_for_igvn(region); 2445 return _gvn.transform(phi); 2446 } 2447 2448 //-------------------------------gen_checkcast--------------------------------- 2449 // Generate a checkcast idiom. Used by both the checkcast bytecode and the 2450 // array store bytecode. Stack must be as-if BEFORE doing the bytecode so the 2451 // uncommon-trap paths work. Adjust stack after this call. 2452 // If failure_control is supplied and not null, it is filled in with 2453 // the control edge for the cast failure. Otherwise, an appropriate 2454 // uncommon trap or exception is thrown. 2455 Node* GraphKit::gen_checkcast(Node *obj, Node* superklass, 2456 Node* *failure_control) { 2457 kill_dead_locals(); // Benefit all the uncommon traps 2458 const TypeKlassPtr *tk = _gvn.type(superklass)->is_klassptr(); 2459 const Type *toop = TypeOopPtr::make_from_klass(tk->klass()); 2460 2461 // Fast cutout: Check the case that the cast is vacuously true. 2462 // This detects the common cases where the test will short-circuit 2463 // away completely. We do this before we perform the null check, 2464 // because if the test is going to turn into zero code, we don't 2465 // want a residual null check left around. (Causes a slowdown, 2466 // for example, in some objArray manipulations, such as a[i]=a[j].) 2467 if (tk->singleton()) { 2468 const TypeOopPtr* objtp = _gvn.type(obj)->isa_oopptr(); 2469 if (objtp != NULL && objtp->klass() != NULL) { 2470 switch (static_subtype_check(tk->klass(), objtp->klass())) { 2471 case SSC_always_true: 2472 return obj; 2473 case SSC_always_false: 2474 // It needs a null check because a null will *pass* the cast check. 2475 // A non-null value will always produce an exception. 2476 return do_null_assert(obj, T_OBJECT); 2477 } 2478 } 2479 } 2480 2481 ciProfileData* data = NULL; 2482 if (failure_control == NULL) { // use MDO in regular case only 2483 assert(java_bc() == Bytecodes::_aastore || 2484 java_bc() == Bytecodes::_checkcast, 2485 "interpreter profiles type checks only for these BCs"); 2486 data = method()->method_data()->bci_to_data(bci()); 2487 } 2488 2489 // Make the merge point 2490 enum { _obj_path = 1, _null_path, PATH_LIMIT }; 2491 RegionNode* region = new (C, PATH_LIMIT) RegionNode(PATH_LIMIT); 2492 Node* phi = new (C, PATH_LIMIT) PhiNode(region, toop); 2493 C->set_has_split_ifs(true); // Has chance for split-if optimization 2494 2495 // Use null-cast information if it is available 2496 bool never_see_null = false; 2497 // If we see an unexpected null at a check-cast we record it and force a 2498 // recompile; the offending check-cast will be compiled to handle NULLs. 2499 // If we see several offending BCIs, then all checkcasts in the 2500 // method will be compiled to handle NULLs. 2501 if (UncommonNullCast // Cutout for this technique 2502 && failure_control == NULL // regular case 2503 && obj != null() // And not the -Xcomp stupid case? 2504 && !too_many_traps(Deoptimization::Reason_null_check)) { 2505 // Finally, check the "null_seen" bit from the interpreter. 2506 if (data == NULL || !data->as_BitData()->null_seen()) { 2507 never_see_null = true; 2508 } 2509 } 2510 2511 // Null check; get casted pointer; set region slot 3 2512 Node* null_ctl = top(); 2513 Node* not_null_obj = null_check_oop(obj, &null_ctl, never_see_null); 2514 2515 // If not_null_obj is dead, only null-path is taken 2516 if (stopped()) { // Doing instance-of on a NULL? 2517 set_control(null_ctl); 2518 return null(); 2519 } 2520 region->init_req(_null_path, null_ctl); 2521 phi ->init_req(_null_path, null()); // Set null path value 2522 2523 Node* cast_obj = NULL; // the casted version of the object 2524 2525 // If the profile has seen exactly one type, narrow to that type. 2526 // (The subsequent subtype check will always fold up.) 2527 if (UseTypeProfile && TypeProfileCasts && data != NULL && 2528 // Counter has never been decremented (due to cast failure). 2529 // ...This is a reasonable thing to expect. It is true of 2530 // all casts inserted by javac to implement generic types. 2531 data->as_CounterData()->count() >= 0 && 2532 !too_many_traps(Deoptimization::Reason_class_check)) { 2533 // (No, this isn't a call, but it's enough like a virtual call 2534 // to use the same ciMethod accessor to get the profile info...) 2535 ciCallProfile profile = method()->call_profile_at_bci(bci()); 2536 if (profile.count() >= 0 && // no cast failures here 2537 profile.has_receiver(0) && 2538 profile.morphism() == 1) { 2539 ciKlass* exact_kls = profile.receiver(0); 2540 int ssc = static_subtype_check(tk->klass(), exact_kls); 2541 if (ssc == SSC_always_true) { 2542 // If we narrow the type to match what the type profile sees, 2543 // we can then remove the rest of the cast. 2544 // This is a win, even if the exact_kls is very specific, 2545 // because downstream operations, such as method calls, 2546 // will often benefit from the sharper type. 2547 Node* exact_obj = not_null_obj; // will get updated in place... 2548 Node* slow_ctl = type_check_receiver(exact_obj, exact_kls, 1.0, 2549 &exact_obj); 2550 { PreserveJVMState pjvms(this); 2551 set_control(slow_ctl); 2552 uncommon_trap(Deoptimization::Reason_class_check, 2553 Deoptimization::Action_maybe_recompile); 2554 } 2555 if (failure_control != NULL) // failure is now impossible 2556 (*failure_control) = top(); 2557 replace_in_map(not_null_obj, exact_obj); 2558 // adjust the type of the phi to the exact klass: 2559 phi->raise_bottom_type(_gvn.type(exact_obj)->meet(TypePtr::NULL_PTR)); 2560 cast_obj = exact_obj; 2561 } 2562 // assert(cast_obj != NULL)... except maybe the profile lied to us. 2563 } 2564 } 2565 2566 if (cast_obj == NULL) { 2567 // Load the object's klass 2568 Node* obj_klass = load_object_klass(not_null_obj); 2569 2570 // Generate the subtype check 2571 Node* not_subtype_ctrl = gen_subtype_check( obj_klass, superklass ); 2572 2573 // Plug in success path into the merge 2574 cast_obj = _gvn.transform(new (C, 2) CheckCastPPNode(control(), 2575 not_null_obj, toop)); 2576 // Failure path ends in uncommon trap (or may be dead - failure impossible) 2577 if (failure_control == NULL) { 2578 if (not_subtype_ctrl != top()) { // If failure is possible 2579 PreserveJVMState pjvms(this); 2580 set_control(not_subtype_ctrl); 2581 builtin_throw(Deoptimization::Reason_class_check, obj_klass); 2582 } 2583 } else { 2584 (*failure_control) = not_subtype_ctrl; 2585 } 2586 } 2587 2588 region->init_req(_obj_path, control()); 2589 phi ->init_req(_obj_path, cast_obj); 2590 2591 // A merge of NULL or Casted-NotNull obj 2592 Node* res = _gvn.transform(phi); 2593 2594 // Note I do NOT always 'replace_in_map(obj,result)' here. 2595 // if( tk->klass()->can_be_primary_super() ) 2596 // This means that if I successfully store an Object into an array-of-String 2597 // I 'forget' that the Object is really now known to be a String. I have to 2598 // do this because we don't have true union types for interfaces - if I store 2599 // a Baz into an array-of-Interface and then tell the optimizer it's an 2600 // Interface, I forget that it's also a Baz and cannot do Baz-like field 2601 // references to it. FIX THIS WHEN UNION TYPES APPEAR! 2602 // replace_in_map( obj, res ); 2603 2604 // Return final merged results 2605 set_control( _gvn.transform(region) ); 2606 record_for_igvn(region); 2607 return res; 2608 } 2609 2610 //------------------------------next_monitor----------------------------------- 2611 // What number should be given to the next monitor? 2612 int GraphKit::next_monitor() { 2613 int current = jvms()->monitor_depth()* C->sync_stack_slots(); 2614 int next = current + C->sync_stack_slots(); 2615 // Keep the toplevel high water mark current: 2616 if (C->fixed_slots() < next) C->set_fixed_slots(next); 2617 return current; 2618 } 2619 2620 //------------------------------insert_mem_bar--------------------------------- 2621 // Memory barrier to avoid floating things around 2622 // The membar serves as a pinch point between both control and all memory slices. 2623 Node* GraphKit::insert_mem_bar(int opcode, Node* precedent) { 2624 MemBarNode* mb = MemBarNode::make(C, opcode, Compile::AliasIdxBot, precedent); 2625 mb->init_req(TypeFunc::Control, control()); 2626 mb->init_req(TypeFunc::Memory, reset_memory()); 2627 Node* membar = _gvn.transform(mb); 2628 set_control(_gvn.transform(new (C, 1) ProjNode(membar,TypeFunc::Control) )); 2629 set_all_memory_call(membar); 2630 return membar; 2631 } 2632 2633 //-------------------------insert_mem_bar_volatile---------------------------- 2634 // Memory barrier to avoid floating things around 2635 // The membar serves as a pinch point between both control and memory(alias_idx). 2636 // If you want to make a pinch point on all memory slices, do not use this 2637 // function (even with AliasIdxBot); use insert_mem_bar() instead. 2638 Node* GraphKit::insert_mem_bar_volatile(int opcode, int alias_idx, Node* precedent) { 2639 // When Parse::do_put_xxx updates a volatile field, it appends a series 2640 // of MemBarVolatile nodes, one for *each* volatile field alias category. 2641 // The first membar is on the same memory slice as the field store opcode. 2642 // This forces the membar to follow the store. (Bug 6500685 broke this.) 2643 // All the other membars (for other volatile slices, including AliasIdxBot, 2644 // which stands for all unknown volatile slices) are control-dependent 2645 // on the first membar. This prevents later volatile loads or stores 2646 // from sliding up past the just-emitted store. 2647 2648 MemBarNode* mb = MemBarNode::make(C, opcode, alias_idx, precedent); 2649 mb->set_req(TypeFunc::Control,control()); 2650 if (alias_idx == Compile::AliasIdxBot) { 2651 mb->set_req(TypeFunc::Memory, merged_memory()->base_memory()); 2652 } else { 2653 assert(!(opcode == Op_Initialize && alias_idx != Compile::AliasIdxRaw), "fix caller"); 2654 mb->set_req(TypeFunc::Memory, memory(alias_idx)); 2655 } 2656 Node* membar = _gvn.transform(mb); 2657 set_control(_gvn.transform(new (C, 1) ProjNode(membar, TypeFunc::Control))); 2658 if (alias_idx == Compile::AliasIdxBot) { 2659 merged_memory()->set_base_memory(_gvn.transform(new (C, 1) ProjNode(membar, TypeFunc::Memory))); 2660 } else { 2661 set_memory(_gvn.transform(new (C, 1) ProjNode(membar, TypeFunc::Memory)),alias_idx); 2662 } 2663 return membar; 2664 } 2665 2666 //------------------------------shared_lock------------------------------------ 2667 // Emit locking code. 2668 FastLockNode* GraphKit::shared_lock(Node* obj) { 2669 // bci is either a monitorenter bc or InvocationEntryBci 2670 // %%% SynchronizationEntryBCI is redundant; use InvocationEntryBci in interfaces 2671 assert(SynchronizationEntryBCI == InvocationEntryBci, ""); 2672 2673 if( !GenerateSynchronizationCode ) 2674 return NULL; // Not locking things? 2675 if (stopped()) // Dead monitor? 2676 return NULL; 2677 2678 assert(dead_locals_are_killed(), "should kill locals before sync. point"); 2679 2680 // Box the stack location 2681 Node* box = _gvn.transform(new (C, 1) BoxLockNode(next_monitor())); 2682 Node* mem = reset_memory(); 2683 2684 FastLockNode * flock = _gvn.transform(new (C, 3) FastLockNode(0, obj, box) )->as_FastLock(); 2685 if (PrintPreciseBiasedLockingStatistics) { 2686 // Create the counters for this fast lock. 2687 flock->create_lock_counter(sync_jvms()); // sync_jvms used to get current bci 2688 } 2689 // Add monitor to debug info for the slow path. If we block inside the 2690 // slow path and de-opt, we need the monitor hanging around 2691 map()->push_monitor( flock ); 2692 2693 const TypeFunc *tf = LockNode::lock_type(); 2694 LockNode *lock = new (C, tf->domain()->cnt()) LockNode(C, tf); 2695 2696 lock->init_req( TypeFunc::Control, control() ); 2697 lock->init_req( TypeFunc::Memory , mem ); 2698 lock->init_req( TypeFunc::I_O , top() ) ; // does no i/o 2699 lock->init_req( TypeFunc::FramePtr, frameptr() ); 2700 lock->init_req( TypeFunc::ReturnAdr, top() ); 2701 2702 lock->init_req(TypeFunc::Parms + 0, obj); 2703 lock->init_req(TypeFunc::Parms + 1, box); 2704 lock->init_req(TypeFunc::Parms + 2, flock); 2705 add_safepoint_edges(lock); 2706 2707 lock = _gvn.transform( lock )->as_Lock(); 2708 2709 // lock has no side-effects, sets few values 2710 set_predefined_output_for_runtime_call(lock, mem, TypeRawPtr::BOTTOM); 2711 2712 insert_mem_bar(Op_MemBarAcquire); 2713 2714 // Add this to the worklist so that the lock can be eliminated 2715 record_for_igvn(lock); 2716 2717 #ifndef PRODUCT 2718 if (PrintLockStatistics) { 2719 // Update the counter for this lock. Don't bother using an atomic 2720 // operation since we don't require absolute accuracy. 2721 lock->create_lock_counter(map()->jvms()); 2722 int adr_type = Compile::AliasIdxRaw; 2723 Node* counter_addr = makecon(TypeRawPtr::make(lock->counter()->addr())); 2724 Node* cnt = make_load(NULL, counter_addr, TypeInt::INT, T_INT, adr_type); 2725 Node* incr = _gvn.transform(new (C, 3) AddINode(cnt, _gvn.intcon(1))); 2726 store_to_memory(control(), counter_addr, incr, T_INT, adr_type); 2727 } 2728 #endif 2729 2730 return flock; 2731 } 2732 2733 2734 //------------------------------shared_unlock---------------------------------- 2735 // Emit unlocking code. 2736 void GraphKit::shared_unlock(Node* box, Node* obj) { 2737 // bci is either a monitorenter bc or InvocationEntryBci 2738 // %%% SynchronizationEntryBCI is redundant; use InvocationEntryBci in interfaces 2739 assert(SynchronizationEntryBCI == InvocationEntryBci, ""); 2740 2741 if( !GenerateSynchronizationCode ) 2742 return; 2743 if (stopped()) { // Dead monitor? 2744 map()->pop_monitor(); // Kill monitor from debug info 2745 return; 2746 } 2747 2748 // Memory barrier to avoid floating things down past the locked region 2749 insert_mem_bar(Op_MemBarRelease); 2750 2751 const TypeFunc *tf = OptoRuntime::complete_monitor_exit_Type(); 2752 UnlockNode *unlock = new (C, tf->domain()->cnt()) UnlockNode(C, tf); 2753 uint raw_idx = Compile::AliasIdxRaw; 2754 unlock->init_req( TypeFunc::Control, control() ); 2755 unlock->init_req( TypeFunc::Memory , memory(raw_idx) ); 2756 unlock->init_req( TypeFunc::I_O , top() ) ; // does no i/o 2757 unlock->init_req( TypeFunc::FramePtr, frameptr() ); 2758 unlock->init_req( TypeFunc::ReturnAdr, top() ); 2759 2760 unlock->init_req(TypeFunc::Parms + 0, obj); 2761 unlock->init_req(TypeFunc::Parms + 1, box); 2762 unlock = _gvn.transform(unlock)->as_Unlock(); 2763 2764 Node* mem = reset_memory(); 2765 2766 // unlock has no side-effects, sets few values 2767 set_predefined_output_for_runtime_call(unlock, mem, TypeRawPtr::BOTTOM); 2768 2769 // Kill monitor from debug info 2770 map()->pop_monitor( ); 2771 } 2772 2773 //-------------------------------get_layout_helper----------------------------- 2774 // If the given klass is a constant or known to be an array, 2775 // fetch the constant layout helper value into constant_value 2776 // and return (Node*)NULL. Otherwise, load the non-constant 2777 // layout helper value, and return the node which represents it. 2778 // This two-faced routine is useful because allocation sites 2779 // almost always feature constant types. 2780 Node* GraphKit::get_layout_helper(Node* klass_node, jint& constant_value) { 2781 const TypeKlassPtr* inst_klass = _gvn.type(klass_node)->isa_klassptr(); 2782 if (!StressReflectiveCode && inst_klass != NULL) { 2783 ciKlass* klass = inst_klass->klass(); 2784 bool xklass = inst_klass->klass_is_exact(); 2785 if (xklass || klass->is_array_klass()) { 2786 jint lhelper = klass->layout_helper(); 2787 if (lhelper != Klass::_lh_neutral_value) { 2788 constant_value = lhelper; 2789 return (Node*) NULL; 2790 } 2791 } 2792 } 2793 constant_value = Klass::_lh_neutral_value; // put in a known value 2794 Node* lhp = basic_plus_adr(klass_node, klass_node, Klass::layout_helper_offset_in_bytes() + sizeof(oopDesc)); 2795 return make_load(NULL, lhp, TypeInt::INT, T_INT); 2796 } 2797 2798 // We just put in an allocate/initialize with a big raw-memory effect. 2799 // Hook selected additional alias categories on the initialization. 2800 static void hook_memory_on_init(GraphKit& kit, int alias_idx, 2801 MergeMemNode* init_in_merge, 2802 Node* init_out_raw) { 2803 DEBUG_ONLY(Node* init_in_raw = init_in_merge->base_memory()); 2804 assert(init_in_merge->memory_at(alias_idx) == init_in_raw, ""); 2805 2806 Node* prevmem = kit.memory(alias_idx); 2807 init_in_merge->set_memory_at(alias_idx, prevmem); 2808 kit.set_memory(init_out_raw, alias_idx); 2809 } 2810 2811 //---------------------------set_output_for_allocation------------------------- 2812 Node* GraphKit::set_output_for_allocation(AllocateNode* alloc, 2813 const TypeOopPtr* oop_type, 2814 bool raw_mem_only) { 2815 int rawidx = Compile::AliasIdxRaw; 2816 alloc->set_req( TypeFunc::FramePtr, frameptr() ); 2817 add_safepoint_edges(alloc); 2818 Node* allocx = _gvn.transform(alloc); 2819 set_control( _gvn.transform(new (C, 1) ProjNode(allocx, TypeFunc::Control) ) ); 2820 // create memory projection for i_o 2821 set_memory ( _gvn.transform( new (C, 1) ProjNode(allocx, TypeFunc::Memory, true) ), rawidx ); 2822 make_slow_call_ex(allocx, env()->OutOfMemoryError_klass(), true); 2823 2824 // create a memory projection as for the normal control path 2825 Node* malloc = _gvn.transform(new (C, 1) ProjNode(allocx, TypeFunc::Memory)); 2826 set_memory(malloc, rawidx); 2827 2828 // a normal slow-call doesn't change i_o, but an allocation does 2829 // we create a separate i_o projection for the normal control path 2830 set_i_o(_gvn.transform( new (C, 1) ProjNode(allocx, TypeFunc::I_O, false) ) ); 2831 Node* rawoop = _gvn.transform( new (C, 1) ProjNode(allocx, TypeFunc::Parms) ); 2832 2833 // put in an initialization barrier 2834 InitializeNode* init = insert_mem_bar_volatile(Op_Initialize, rawidx, 2835 rawoop)->as_Initialize(); 2836 assert(alloc->initialization() == init, "2-way macro link must work"); 2837 assert(init ->allocation() == alloc, "2-way macro link must work"); 2838 if (ReduceFieldZeroing && !raw_mem_only) { 2839 // Extract memory strands which may participate in the new object's 2840 // initialization, and source them from the new InitializeNode. 2841 // This will allow us to observe initializations when they occur, 2842 // and link them properly (as a group) to the InitializeNode. 2843 assert(init->in(InitializeNode::Memory) == malloc, ""); 2844 MergeMemNode* minit_in = MergeMemNode::make(C, malloc); 2845 init->set_req(InitializeNode::Memory, minit_in); 2846 record_for_igvn(minit_in); // fold it up later, if possible 2847 Node* minit_out = memory(rawidx); 2848 assert(minit_out->is_Proj() && minit_out->in(0) == init, ""); 2849 if (oop_type->isa_aryptr()) { 2850 const TypePtr* telemref = oop_type->add_offset(Type::OffsetBot); 2851 int elemidx = C->get_alias_index(telemref); 2852 hook_memory_on_init(*this, elemidx, minit_in, minit_out); 2853 } else if (oop_type->isa_instptr()) { 2854 ciInstanceKlass* ik = oop_type->klass()->as_instance_klass(); 2855 for (int i = 0, len = ik->nof_nonstatic_fields(); i < len; i++) { 2856 ciField* field = ik->nonstatic_field_at(i); 2857 if (field->offset() >= TrackedInitializationLimit * HeapWordSize) 2858 continue; // do not bother to track really large numbers of fields 2859 // Find (or create) the alias category for this field: 2860 int fieldidx = C->alias_type(field)->index(); 2861 hook_memory_on_init(*this, fieldidx, minit_in, minit_out); 2862 } 2863 } 2864 } 2865 2866 // Cast raw oop to the real thing... 2867 Node* javaoop = new (C, 2) CheckCastPPNode(control(), rawoop, oop_type); 2868 javaoop = _gvn.transform(javaoop); 2869 C->set_recent_alloc(control(), javaoop); 2870 assert(just_allocated_object(control()) == javaoop, "just allocated"); 2871 2872 #ifdef ASSERT 2873 { // Verify that the AllocateNode::Ideal_allocation recognizers work: 2874 assert(AllocateNode::Ideal_allocation(rawoop, &_gvn) == alloc, 2875 "Ideal_allocation works"); 2876 assert(AllocateNode::Ideal_allocation(javaoop, &_gvn) == alloc, 2877 "Ideal_allocation works"); 2878 if (alloc->is_AllocateArray()) { 2879 assert(AllocateArrayNode::Ideal_array_allocation(rawoop, &_gvn) == alloc->as_AllocateArray(), 2880 "Ideal_allocation works"); 2881 assert(AllocateArrayNode::Ideal_array_allocation(javaoop, &_gvn) == alloc->as_AllocateArray(), 2882 "Ideal_allocation works"); 2883 } else { 2884 assert(alloc->in(AllocateNode::ALength)->is_top(), "no length, please"); 2885 } 2886 } 2887 #endif //ASSERT 2888 2889 return javaoop; 2890 } 2891 2892 //---------------------------new_instance-------------------------------------- 2893 // This routine takes a klass_node which may be constant (for a static type) 2894 // or may be non-constant (for reflective code). It will work equally well 2895 // for either, and the graph will fold nicely if the optimizer later reduces 2896 // the type to a constant. 2897 // The optional arguments are for specialized use by intrinsics: 2898 // - If 'extra_slow_test' if not null is an extra condition for the slow-path. 2899 // - If 'raw_mem_only', do not cast the result to an oop. 2900 // - If 'return_size_val', report the the total object size to the caller. 2901 Node* GraphKit::new_instance(Node* klass_node, 2902 Node* extra_slow_test, 2903 bool raw_mem_only, // affect only raw memory 2904 Node* *return_size_val) { 2905 // Compute size in doublewords 2906 // The size is always an integral number of doublewords, represented 2907 // as a positive bytewise size stored in the klass's layout_helper. 2908 // The layout_helper also encodes (in a low bit) the need for a slow path. 2909 jint layout_con = Klass::_lh_neutral_value; 2910 Node* layout_val = get_layout_helper(klass_node, layout_con); 2911 int layout_is_con = (layout_val == NULL); 2912 2913 if (extra_slow_test == NULL) extra_slow_test = intcon(0); 2914 // Generate the initial go-slow test. It's either ALWAYS (return a 2915 // Node for 1) or NEVER (return a NULL) or perhaps (in the reflective 2916 // case) a computed value derived from the layout_helper. 2917 Node* initial_slow_test = NULL; 2918 if (layout_is_con) { 2919 assert(!StressReflectiveCode, "stress mode does not use these paths"); 2920 bool must_go_slow = Klass::layout_helper_needs_slow_path(layout_con); 2921 initial_slow_test = must_go_slow? intcon(1): extra_slow_test; 2922 2923 } else { // reflective case 2924 // This reflective path is used by Unsafe.allocateInstance. 2925 // (It may be stress-tested by specifying StressReflectiveCode.) 2926 // Basically, we want to get into the VM is there's an illegal argument. 2927 Node* bit = intcon(Klass::_lh_instance_slow_path_bit); 2928 initial_slow_test = _gvn.transform( new (C, 3) AndINode(layout_val, bit) ); 2929 if (extra_slow_test != intcon(0)) { 2930 initial_slow_test = _gvn.transform( new (C, 3) OrINode(initial_slow_test, extra_slow_test) ); 2931 } 2932 // (Macro-expander will further convert this to a Bool, if necessary.) 2933 } 2934 2935 // Find the size in bytes. This is easy; it's the layout_helper. 2936 // The size value must be valid even if the slow path is taken. 2937 Node* size = NULL; 2938 if (layout_is_con) { 2939 size = MakeConX(Klass::layout_helper_size_in_bytes(layout_con)); 2940 } else { // reflective case 2941 // This reflective path is used by clone and Unsafe.allocateInstance. 2942 size = ConvI2X(layout_val); 2943 2944 // Clear the low bits to extract layout_helper_size_in_bytes: 2945 assert((int)Klass::_lh_instance_slow_path_bit < BytesPerLong, "clear bit"); 2946 Node* mask = MakeConX(~ (intptr_t)right_n_bits(LogBytesPerLong)); 2947 size = _gvn.transform( new (C, 3) AndXNode(size, mask) ); 2948 } 2949 if (return_size_val != NULL) { 2950 (*return_size_val) = size; 2951 } 2952 2953 // This is a precise notnull oop of the klass. 2954 // (Actually, it need not be precise if this is a reflective allocation.) 2955 // It's what we cast the result to. 2956 const TypeKlassPtr* tklass = _gvn.type(klass_node)->isa_klassptr(); 2957 if (!tklass) tklass = TypeKlassPtr::OBJECT; 2958 const TypeOopPtr* oop_type = tklass->as_instance_type(); 2959 2960 // Now generate allocation code 2961 2962 // The entire memory state is needed for slow path of the allocation 2963 // since GC and deoptimization can happened. 2964 Node *mem = reset_memory(); 2965 set_all_memory(mem); // Create new memory state 2966 2967 AllocateNode* alloc 2968 = new (C, AllocateNode::ParmLimit) 2969 AllocateNode(C, AllocateNode::alloc_type(), 2970 control(), mem, i_o(), 2971 size, klass_node, 2972 initial_slow_test); 2973 2974 return set_output_for_allocation(alloc, oop_type, raw_mem_only); 2975 } 2976 2977 //-------------------------------new_array------------------------------------- 2978 // helper for both newarray and anewarray 2979 // The 'length' parameter is (obviously) the length of the array. 2980 // See comments on new_instance for the meaning of the other arguments. 2981 Node* GraphKit::new_array(Node* klass_node, // array klass (maybe variable) 2982 Node* length, // number of array elements 2983 int nargs, // number of arguments to push back for uncommon trap 2984 bool raw_mem_only, // affect only raw memory 2985 Node* *return_size_val) { 2986 jint layout_con = Klass::_lh_neutral_value; 2987 Node* layout_val = get_layout_helper(klass_node, layout_con); 2988 int layout_is_con = (layout_val == NULL); 2989 2990 if (!layout_is_con && !StressReflectiveCode && 2991 !too_many_traps(Deoptimization::Reason_class_check)) { 2992 // This is a reflective array creation site. 2993 // Optimistically assume that it is a subtype of Object[], 2994 // so that we can fold up all the address arithmetic. 2995 layout_con = Klass::array_layout_helper(T_OBJECT); 2996 Node* cmp_lh = _gvn.transform( new(C, 3) CmpINode(layout_val, intcon(layout_con)) ); 2997 Node* bol_lh = _gvn.transform( new(C, 2) BoolNode(cmp_lh, BoolTest::eq) ); 2998 { BuildCutout unless(this, bol_lh, PROB_MAX); 2999 _sp += nargs; 3000 uncommon_trap(Deoptimization::Reason_class_check, 3001 Deoptimization::Action_maybe_recompile); 3002 } 3003 layout_val = NULL; 3004 layout_is_con = true; 3005 } 3006 3007 // Generate the initial go-slow test. Make sure we do not overflow 3008 // if length is huge (near 2Gig) or negative! We do not need 3009 // exact double-words here, just a close approximation of needed 3010 // double-words. We can't add any offset or rounding bits, lest we 3011 // take a size -1 of bytes and make it positive. Use an unsigned 3012 // compare, so negative sizes look hugely positive. 3013 int fast_size_limit = FastAllocateSizeLimit; 3014 if (layout_is_con) { 3015 assert(!StressReflectiveCode, "stress mode does not use these paths"); 3016 // Increase the size limit if we have exact knowledge of array type. 3017 int log2_esize = Klass::layout_helper_log2_element_size(layout_con); 3018 fast_size_limit <<= (LogBytesPerLong - log2_esize); 3019 } 3020 3021 Node* initial_slow_cmp = _gvn.transform( new (C, 3) CmpUNode( length, intcon( fast_size_limit ) ) ); 3022 Node* initial_slow_test = _gvn.transform( new (C, 2) BoolNode( initial_slow_cmp, BoolTest::gt ) ); 3023 if (initial_slow_test->is_Bool()) { 3024 // Hide it behind a CMoveI, or else PhaseIdealLoop::split_up will get sick. 3025 initial_slow_test = initial_slow_test->as_Bool()->as_int_value(&_gvn); 3026 } 3027 3028 // --- Size Computation --- 3029 // array_size = round_to_heap(array_header + (length << elem_shift)); 3030 // where round_to_heap(x) == round_to(x, MinObjAlignmentInBytes) 3031 // and round_to(x, y) == ((x + y-1) & ~(y-1)) 3032 // The rounding mask is strength-reduced, if possible. 3033 int round_mask = MinObjAlignmentInBytes - 1; 3034 Node* header_size = NULL; 3035 int header_size_min = arrayOopDesc::base_offset_in_bytes(T_BYTE); 3036 // (T_BYTE has the weakest alignment and size restrictions...) 3037 if (layout_is_con) { 3038 int hsize = Klass::layout_helper_header_size(layout_con); 3039 int eshift = Klass::layout_helper_log2_element_size(layout_con); 3040 BasicType etype = Klass::layout_helper_element_type(layout_con); 3041 if ((round_mask & ~right_n_bits(eshift)) == 0) 3042 round_mask = 0; // strength-reduce it if it goes away completely 3043 assert((hsize & right_n_bits(eshift)) == 0, "hsize is pre-rounded"); 3044 assert(header_size_min <= hsize, "generic minimum is smallest"); 3045 header_size_min = hsize; 3046 header_size = intcon(hsize + round_mask); 3047 } else { 3048 Node* hss = intcon(Klass::_lh_header_size_shift); 3049 Node* hsm = intcon(Klass::_lh_header_size_mask); 3050 Node* hsize = _gvn.transform( new(C, 3) URShiftINode(layout_val, hss) ); 3051 hsize = _gvn.transform( new(C, 3) AndINode(hsize, hsm) ); 3052 Node* mask = intcon(round_mask); 3053 header_size = _gvn.transform( new(C, 3) AddINode(hsize, mask) ); 3054 } 3055 3056 Node* elem_shift = NULL; 3057 if (layout_is_con) { 3058 int eshift = Klass::layout_helper_log2_element_size(layout_con); 3059 if (eshift != 0) 3060 elem_shift = intcon(eshift); 3061 } else { 3062 // There is no need to mask or shift this value. 3063 // The semantics of LShiftINode include an implicit mask to 0x1F. 3064 assert(Klass::_lh_log2_element_size_shift == 0, "use shift in place"); 3065 elem_shift = layout_val; 3066 } 3067 3068 // Transition to native address size for all offset calculations: 3069 Node* lengthx = ConvI2X(length); 3070 Node* headerx = ConvI2X(header_size); 3071 #ifdef _LP64 3072 { const TypeLong* tllen = _gvn.find_long_type(lengthx); 3073 if (tllen != NULL && tllen->_lo < 0) { 3074 // Add a manual constraint to a positive range. Cf. array_element_address. 3075 jlong size_max = arrayOopDesc::max_array_length(T_BYTE); 3076 if (size_max > tllen->_hi) size_max = tllen->_hi; 3077 const TypeLong* tlcon = TypeLong::make(CONST64(0), size_max, Type::WidenMin); 3078 lengthx = _gvn.transform( new (C, 2) ConvI2LNode(length, tlcon)); 3079 } 3080 } 3081 #endif 3082 3083 // Combine header size (plus rounding) and body size. Then round down. 3084 // This computation cannot overflow, because it is used only in two 3085 // places, one where the length is sharply limited, and the other 3086 // after a successful allocation. 3087 Node* abody = lengthx; 3088 if (elem_shift != NULL) 3089 abody = _gvn.transform( new(C, 3) LShiftXNode(lengthx, elem_shift) ); 3090 Node* size = _gvn.transform( new(C, 3) AddXNode(headerx, abody) ); 3091 if (round_mask != 0) { 3092 Node* mask = MakeConX(~round_mask); 3093 size = _gvn.transform( new(C, 3) AndXNode(size, mask) ); 3094 } 3095 // else if round_mask == 0, the size computation is self-rounding 3096 3097 if (return_size_val != NULL) { 3098 // This is the size 3099 (*return_size_val) = size; 3100 } 3101 3102 // Now generate allocation code 3103 3104 // The entire memory state is needed for slow path of the allocation 3105 // since GC and deoptimization can happened. 3106 Node *mem = reset_memory(); 3107 set_all_memory(mem); // Create new memory state 3108 3109 // Create the AllocateArrayNode and its result projections 3110 AllocateArrayNode* alloc 3111 = new (C, AllocateArrayNode::ParmLimit) 3112 AllocateArrayNode(C, AllocateArrayNode::alloc_type(), 3113 control(), mem, i_o(), 3114 size, klass_node, 3115 initial_slow_test, 3116 length); 3117 3118 // Cast to correct type. Note that the klass_node may be constant or not, 3119 // and in the latter case the actual array type will be inexact also. 3120 // (This happens via a non-constant argument to inline_native_newArray.) 3121 // In any case, the value of klass_node provides the desired array type. 3122 const TypeInt* length_type = _gvn.find_int_type(length); 3123 const TypeOopPtr* ary_type = _gvn.type(klass_node)->is_klassptr()->as_instance_type(); 3124 if (ary_type->isa_aryptr() && length_type != NULL) { 3125 // Try to get a better type than POS for the size 3126 ary_type = ary_type->is_aryptr()->cast_to_size(length_type); 3127 } 3128 3129 Node* javaoop = set_output_for_allocation(alloc, ary_type, raw_mem_only); 3130 3131 // Cast length on remaining path to be as narrow as possible 3132 if (map()->find_edge(length) >= 0) { 3133 Node* ccast = alloc->make_ideal_length(ary_type, &_gvn); 3134 if (ccast != length) { 3135 _gvn.set_type_bottom(ccast); 3136 record_for_igvn(ccast); 3137 replace_in_map(length, ccast); 3138 } 3139 } 3140 3141 return javaoop; 3142 } 3143 3144 // The following "Ideal_foo" functions are placed here because they recognize 3145 // the graph shapes created by the functions immediately above. 3146 3147 //---------------------------Ideal_allocation---------------------------------- 3148 // Given an oop pointer or raw pointer, see if it feeds from an AllocateNode. 3149 AllocateNode* AllocateNode::Ideal_allocation(Node* ptr, PhaseTransform* phase) { 3150 if (ptr == NULL) { // reduce dumb test in callers 3151 return NULL; 3152 } 3153 if (ptr->is_CheckCastPP()) { // strip a raw-to-oop cast 3154 ptr = ptr->in(1); 3155 if (ptr == NULL) return NULL; 3156 } 3157 if (ptr->is_Proj()) { 3158 Node* allo = ptr->in(0); 3159 if (allo != NULL && allo->is_Allocate()) { 3160 return allo->as_Allocate(); 3161 } 3162 } 3163 // Report failure to match. 3164 return NULL; 3165 } 3166 3167 // Fancy version which also strips off an offset (and reports it to caller). 3168 AllocateNode* AllocateNode::Ideal_allocation(Node* ptr, PhaseTransform* phase, 3169 intptr_t& offset) { 3170 Node* base = AddPNode::Ideal_base_and_offset(ptr, phase, offset); 3171 if (base == NULL) return NULL; 3172 return Ideal_allocation(base, phase); 3173 } 3174 3175 // Trace Initialize <- Proj[Parm] <- Allocate 3176 AllocateNode* InitializeNode::allocation() { 3177 Node* rawoop = in(InitializeNode::RawAddress); 3178 if (rawoop->is_Proj()) { 3179 Node* alloc = rawoop->in(0); 3180 if (alloc->is_Allocate()) { 3181 return alloc->as_Allocate(); 3182 } 3183 } 3184 return NULL; 3185 } 3186 3187 // Trace Allocate -> Proj[Parm] -> Initialize 3188 InitializeNode* AllocateNode::initialization() { 3189 ProjNode* rawoop = proj_out(AllocateNode::RawAddress); 3190 if (rawoop == NULL) return NULL; 3191 for (DUIterator_Fast imax, i = rawoop->fast_outs(imax); i < imax; i++) { 3192 Node* init = rawoop->fast_out(i); 3193 if (init->is_Initialize()) { 3194 assert(init->as_Initialize()->allocation() == this, "2-way link"); 3195 return init->as_Initialize(); 3196 } 3197 } 3198 return NULL; 3199 } 3200 3201 void GraphKit::g1_write_barrier_pre(Node* obj, 3202 Node* adr, 3203 uint alias_idx, 3204 Node* val, 3205 const Type* val_type, 3206 BasicType bt) { 3207 IdealKit ideal(gvn(), control(), merged_memory(), true); 3208 #define __ ideal. 3209 __ declares_done(); 3210 3211 Node* thread = __ thread(); 3212 3213 Node* no_ctrl = NULL; 3214 Node* no_base = __ top(); 3215 Node* zero = __ ConI(0); 3216 3217 float likely = PROB_LIKELY(0.999); 3218 float unlikely = PROB_UNLIKELY(0.999); 3219 3220 BasicType active_type = in_bytes(PtrQueue::byte_width_of_active()) == 4 ? T_INT : T_BYTE; 3221 assert(in_bytes(PtrQueue::byte_width_of_active()) == 4 || in_bytes(PtrQueue::byte_width_of_active()) == 1, "flag width"); 3222 3223 // Offsets into the thread 3224 const int marking_offset = in_bytes(JavaThread::satb_mark_queue_offset() + // 648 3225 PtrQueue::byte_offset_of_active()); 3226 const int index_offset = in_bytes(JavaThread::satb_mark_queue_offset() + // 656 3227 PtrQueue::byte_offset_of_index()); 3228 const int buffer_offset = in_bytes(JavaThread::satb_mark_queue_offset() + // 652 3229 PtrQueue::byte_offset_of_buf()); 3230 // Now the actual pointers into the thread 3231 3232 // set_control( ctl); 3233 3234 Node* marking_adr = __ AddP(no_base, thread, __ ConX(marking_offset)); 3235 Node* buffer_adr = __ AddP(no_base, thread, __ ConX(buffer_offset)); 3236 Node* index_adr = __ AddP(no_base, thread, __ ConX(index_offset)); 3237 3238 // Now some of the values 3239 3240 Node* marking = __ load(__ ctrl(), marking_adr, TypeInt::INT, active_type, Compile::AliasIdxRaw); 3241 3242 // if (!marking) 3243 __ if_then(marking, BoolTest::ne, zero); { 3244 Node* index = __ load(__ ctrl(), index_adr, TypeInt::INT, T_INT, Compile::AliasIdxRaw); 3245 3246 const Type* t1 = adr->bottom_type(); 3247 const Type* t2 = val->bottom_type(); 3248 3249 Node* orig = __ load(no_ctrl, adr, val_type, bt, alias_idx); 3250 // if (orig != NULL) 3251 __ if_then(orig, BoolTest::ne, null()); { 3252 Node* buffer = __ load(__ ctrl(), buffer_adr, TypeRawPtr::NOTNULL, T_ADDRESS, Compile::AliasIdxRaw); 3253 3254 // load original value 3255 // alias_idx correct?? 3256 3257 // is the queue for this thread full? 3258 __ if_then(index, BoolTest::ne, zero, likely); { 3259 3260 // decrement the index 3261 Node* next_index = __ SubI(index, __ ConI(sizeof(intptr_t))); 3262 Node* next_indexX = next_index; 3263 #ifdef _LP64 3264 // We could refine the type for what it's worth 3265 // const TypeLong* lidxtype = TypeLong::make(CONST64(0), get_size_from_queue); 3266 next_indexX = _gvn.transform( new (C, 2) ConvI2LNode(next_index, TypeLong::make(0, max_jlong, Type::WidenMax)) ); 3267 #endif // _LP64 3268 3269 // Now get the buffer location we will log the original value into and store it 3270 3271 Node *log_addr = __ AddP(no_base, buffer, next_indexX); 3272 // __ store(__ ctrl(), log_addr, orig, T_OBJECT, C->get_alias_index(TypeOopPtr::BOTTOM)); 3273 __ store(__ ctrl(), log_addr, orig, T_OBJECT, Compile::AliasIdxRaw); 3274 3275 3276 // update the index 3277 // __ store(__ ctrl(), index_adr, next_index, T_INT, Compile::AliasIdxRaw); 3278 // This is a hack to force this store to occur before the oop store that is coming up 3279 __ store(__ ctrl(), index_adr, next_index, T_INT, C->get_alias_index(TypeOopPtr::BOTTOM)); 3280 3281 } __ else_(); { 3282 3283 // logging buffer is full, call the runtime 3284 const TypeFunc *tf = OptoRuntime::g1_wb_pre_Type(); 3285 // __ make_leaf_call(tf, OptoRuntime::g1_wb_pre_Java(), "g1_wb_pre", orig, thread); 3286 __ make_leaf_call(tf, CAST_FROM_FN_PTR(address, SharedRuntime::g1_wb_pre), "g1_wb_pre", orig, thread); 3287 } __ end_if(); 3288 } __ end_if(); 3289 } __ end_if(); 3290 3291 __ drain_delay_transform(); 3292 set_control( __ ctrl()); 3293 set_all_memory( __ merged_memory()); 3294 3295 #undef __ 3296 } 3297 3298 // 3299 // Update the card table and add card address to the queue 3300 // 3301 void GraphKit::g1_mark_card(IdealKit* ideal, Node* card_adr, Node* store, Node* index, Node* index_adr, Node* buffer, const TypeFunc* tf) { 3302 #define __ ideal-> 3303 Node* zero = __ ConI(0); 3304 Node* no_base = __ top(); 3305 BasicType card_bt = T_BYTE; 3306 // Smash zero into card. MUST BE ORDERED WRT TO STORE 3307 __ storeCM(__ ctrl(), card_adr, zero, store, card_bt, Compile::AliasIdxRaw); 3308 3309 // Now do the queue work 3310 __ if_then(index, BoolTest::ne, zero); { 3311 3312 Node* next_index = __ SubI(index, __ ConI(sizeof(intptr_t))); 3313 Node* next_indexX = next_index; 3314 #ifdef _LP64 3315 // We could refine the type for what it's worth 3316 // const TypeLong* lidxtype = TypeLong::make(CONST64(0), get_size_from_queue); 3317 next_indexX = _gvn.transform( new (C, 2) ConvI2LNode(next_index, TypeLong::make(0, max_jlong, Type::WidenMax)) ); 3318 #endif // _LP64 3319 Node* log_addr = __ AddP(no_base, buffer, next_indexX); 3320 3321 __ store(__ ctrl(), log_addr, card_adr, T_ADDRESS, Compile::AliasIdxRaw); 3322 __ store(__ ctrl(), index_adr, next_index, T_INT, Compile::AliasIdxRaw); 3323 3324 } __ else_(); { 3325 __ make_leaf_call(tf, CAST_FROM_FN_PTR(address, SharedRuntime::g1_wb_post), "g1_wb_post", card_adr, __ thread()); 3326 } __ end_if(); 3327 #undef __ 3328 } 3329 3330 void GraphKit::g1_write_barrier_post(Node* store, 3331 Node* obj, 3332 Node* adr, 3333 uint alias_idx, 3334 Node* val, 3335 BasicType bt, 3336 bool use_precise) { 3337 // If we are writing a NULL then we need no post barrier 3338 3339 if (val != NULL && val->is_Con() && val->bottom_type() == TypePtr::NULL_PTR) { 3340 // Must be NULL 3341 const Type* t = val->bottom_type(); 3342 assert(t == Type::TOP || t == TypePtr::NULL_PTR, "must be NULL"); 3343 // No post barrier if writing NULLx 3344 return; 3345 } 3346 3347 if (!use_precise) { 3348 // All card marks for a (non-array) instance are in one place: 3349 adr = obj; 3350 } 3351 // (Else it's an array (or unknown), and we want more precise card marks.) 3352 assert(adr != NULL, ""); 3353 3354 IdealKit ideal(gvn(), control(), merged_memory(), true); 3355 #define __ ideal. 3356 __ declares_done(); 3357 3358 Node* thread = __ thread(); 3359 3360 Node* no_ctrl = NULL; 3361 Node* no_base = __ top(); 3362 float likely = PROB_LIKELY(0.999); 3363 float unlikely = PROB_UNLIKELY(0.999); 3364 Node* zero = __ ConI(0); 3365 Node* zeroX = __ ConX(0); 3366 3367 // Get the alias_index for raw card-mark memory 3368 const TypePtr* card_type = TypeRawPtr::BOTTOM; 3369 3370 const TypeFunc *tf = OptoRuntime::g1_wb_post_Type(); 3371 3372 // Offsets into the thread 3373 const int index_offset = in_bytes(JavaThread::dirty_card_queue_offset() + 3374 PtrQueue::byte_offset_of_index()); 3375 const int buffer_offset = in_bytes(JavaThread::dirty_card_queue_offset() + 3376 PtrQueue::byte_offset_of_buf()); 3377 3378 // Pointers into the thread 3379 3380 Node* buffer_adr = __ AddP(no_base, thread, __ ConX(buffer_offset)); 3381 Node* index_adr = __ AddP(no_base, thread, __ ConX(index_offset)); 3382 3383 // Now some values 3384 3385 Node* index = __ load(no_ctrl, index_adr, TypeInt::INT, T_INT, Compile::AliasIdxRaw); 3386 Node* buffer = __ load(no_ctrl, buffer_adr, TypeRawPtr::NOTNULL, T_ADDRESS, Compile::AliasIdxRaw); 3387 3388 3389 // Convert the store obj pointer to an int prior to doing math on it 3390 // Use addr not obj gets accurate card marks 3391 3392 // Node* cast = __ CastPX(no_ctrl, adr /* obj */); 3393 3394 // Must use ctrl to prevent "integerized oop" existing across safepoint 3395 Node* cast = __ CastPX(__ ctrl(), ( use_precise ? adr : obj )); 3396 3397 // Divide pointer by card size 3398 Node* card_offset = __ URShiftX( cast, __ ConI(CardTableModRefBS::card_shift) ); 3399 3400 // Combine card table base and card offset 3401 Node *card_adr = __ AddP(no_base, byte_map_base_node(), card_offset ); 3402 3403 // If we know the value being stored does it cross regions? 3404 3405 if (val != NULL) { 3406 // Does the store cause us to cross regions? 3407 3408 // Should be able to do an unsigned compare of region_size instead of 3409 // and extra shift. Do we have an unsigned compare?? 3410 // Node* region_size = __ ConI(1 << HeapRegion::LogOfHRGrainBytes); 3411 Node* xor_res = __ URShiftX ( __ XorX( cast, __ CastPX(__ ctrl(), val)), __ ConI(HeapRegion::LogOfHRGrainBytes)); 3412 3413 // if (xor_res == 0) same region so skip 3414 __ if_then(xor_res, BoolTest::ne, zeroX); { 3415 3416 // No barrier if we are storing a NULL 3417 __ if_then(val, BoolTest::ne, null(), unlikely); { 3418 3419 // Ok must mark the card if not already dirty 3420 3421 // load the original value of the card 3422 Node* card_val = __ load(__ ctrl(), card_adr, TypeInt::INT, T_BYTE, Compile::AliasIdxRaw); 3423 3424 __ if_then(card_val, BoolTest::ne, zero); { 3425 g1_mark_card(&ideal, card_adr, store, index, index_adr, buffer, tf); 3426 } __ end_if(); 3427 } __ end_if(); 3428 } __ end_if(); 3429 } else { 3430 g1_mark_card(&ideal, card_adr, store, index, index_adr, buffer, tf); 3431 } 3432 3433 3434 __ drain_delay_transform(); 3435 set_control( __ ctrl()); 3436 set_all_memory( __ merged_memory()); 3437 #undef __ 3438 3439 }