1 /* 2 * Copyright (c) 2001, 2015, Oracle and/or its affiliates. All rights reserved. 3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. 4 * 5 * This code is free software; you can redistribute it and/or modify it 6 * under the terms of the GNU General Public License version 2 only, as 7 * published by the Free Software Foundation. 8 * 9 * This code is distributed in the hope that it will be useful, but WITHOUT 10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 12 * version 2 for more details (a copy is included in the LICENSE file that 13 * accompanied this code). 14 * 15 * You should have received a copy of the GNU General Public License version 16 * 2 along with this work; if not, write to the Free Software Foundation, 17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. 18 * 19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA 20 * or visit www.oracle.com if you need additional information or have any 21 * questions. 22 * 23 */ 24 25 #include "precompiled.hpp" 26 #include "compiler/compileLog.hpp" 27 #include "gc_implementation/g1/g1SATBCardTableModRefBS.hpp" 28 #include "gc_implementation/g1/heapRegion.hpp" 29 #include "gc_interface/collectedHeap.hpp" 30 #include "memory/barrierSet.hpp" 31 #include "memory/cardTableModRefBS.hpp" 32 #include "opto/addnode.hpp" 33 #include "opto/graphKit.hpp" 34 #include "opto/idealKit.hpp" 35 #include "opto/locknode.hpp" 36 #include "opto/machnode.hpp" 37 #include "opto/parse.hpp" 38 #include "opto/rootnode.hpp" 39 #include "opto/runtime.hpp" 40 #include "runtime/deoptimization.hpp" 41 #include "runtime/sharedRuntime.hpp" 42 43 //----------------------------GraphKit----------------------------------------- 44 // Main utility constructor. 45 GraphKit::GraphKit(JVMState* jvms) 46 : Phase(Phase::Parser), 47 _env(C->env()), 48 _gvn(*C->initial_gvn()) 49 { 50 _exceptions = jvms->map()->next_exception(); 51 if (_exceptions != NULL) jvms->map()->set_next_exception(NULL); 52 set_jvms(jvms); 53 } 54 55 // Private constructor for parser. 56 GraphKit::GraphKit() 57 : Phase(Phase::Parser), 58 _env(C->env()), 59 _gvn(*C->initial_gvn()) 60 { 61 _exceptions = NULL; 62 set_map(NULL); 63 debug_only(_sp = -99); 64 debug_only(set_bci(-99)); 65 } 66 67 68 69 //---------------------------clean_stack--------------------------------------- 70 // Clear away rubbish from the stack area of the JVM state. 71 // This destroys any arguments that may be waiting on the stack. 72 void GraphKit::clean_stack(int from_sp) { 73 SafePointNode* map = this->map(); 74 JVMState* jvms = this->jvms(); 75 int stk_size = jvms->stk_size(); 76 int stkoff = jvms->stkoff(); 77 Node* top = this->top(); 78 for (int i = from_sp; i < stk_size; i++) { 79 if (map->in(stkoff + i) != top) { 80 map->set_req(stkoff + i, top); 81 } 82 } 83 } 84 85 86 //--------------------------------sync_jvms----------------------------------- 87 // Make sure our current jvms agrees with our parse state. 88 JVMState* GraphKit::sync_jvms() const { 89 JVMState* jvms = this->jvms(); 90 jvms->set_bci(bci()); // Record the new bci in the JVMState 91 jvms->set_sp(sp()); // Record the new sp in the JVMState 92 assert(jvms_in_sync(), "jvms is now in sync"); 93 return jvms; 94 } 95 96 //--------------------------------sync_jvms_for_reexecute--------------------- 97 // Make sure our current jvms agrees with our parse state. This version 98 // uses the reexecute_sp for reexecuting bytecodes. 99 JVMState* GraphKit::sync_jvms_for_reexecute() { 100 JVMState* jvms = this->jvms(); 101 jvms->set_bci(bci()); // Record the new bci in the JVMState 102 jvms->set_sp(reexecute_sp()); // Record the new sp in the JVMState 103 return jvms; 104 } 105 106 #ifdef ASSERT 107 bool GraphKit::jvms_in_sync() const { 108 Parse* parse = is_Parse(); 109 if (parse == NULL) { 110 if (bci() != jvms()->bci()) return false; 111 if (sp() != (int)jvms()->sp()) return false; 112 return true; 113 } 114 if (jvms()->method() != parse->method()) return false; 115 if (jvms()->bci() != parse->bci()) return false; 116 int jvms_sp = jvms()->sp(); 117 if (jvms_sp != parse->sp()) return false; 118 int jvms_depth = jvms()->depth(); 119 if (jvms_depth != parse->depth()) return false; 120 return true; 121 } 122 123 // Local helper checks for special internal merge points 124 // used to accumulate and merge exception states. 125 // They are marked by the region's in(0) edge being the map itself. 126 // Such merge points must never "escape" into the parser at large, 127 // until they have been handed to gvn.transform. 128 static bool is_hidden_merge(Node* reg) { 129 if (reg == NULL) return false; 130 if (reg->is_Phi()) { 131 reg = reg->in(0); 132 if (reg == NULL) return false; 133 } 134 return reg->is_Region() && reg->in(0) != NULL && reg->in(0)->is_Root(); 135 } 136 137 void GraphKit::verify_map() const { 138 if (map() == NULL) return; // null map is OK 139 assert(map()->req() <= jvms()->endoff(), "no extra garbage on map"); 140 assert(!map()->has_exceptions(), "call add_exception_states_from 1st"); 141 assert(!is_hidden_merge(control()), "call use_exception_state, not set_map"); 142 } 143 144 void GraphKit::verify_exception_state(SafePointNode* ex_map) { 145 assert(ex_map->next_exception() == NULL, "not already part of a chain"); 146 assert(has_saved_ex_oop(ex_map), "every exception state has an ex_oop"); 147 } 148 #endif 149 150 //---------------------------stop_and_kill_map--------------------------------- 151 // Set _map to NULL, signalling a stop to further bytecode execution. 152 // First smash the current map's control to a constant, to mark it dead. 153 void GraphKit::stop_and_kill_map() { 154 SafePointNode* dead_map = stop(); 155 if (dead_map != NULL) { 156 dead_map->disconnect_inputs(NULL, C); // Mark the map as killed. 157 assert(dead_map->is_killed(), "must be so marked"); 158 } 159 } 160 161 162 //--------------------------------stopped-------------------------------------- 163 // Tell if _map is NULL, or control is top. 164 bool GraphKit::stopped() { 165 if (map() == NULL) return true; 166 else if (control() == top()) return true; 167 else return false; 168 } 169 170 171 //-----------------------------has_ex_handler---------------------------------- 172 // Tell if this method or any caller method has exception handlers. 173 bool GraphKit::has_ex_handler() { 174 for (JVMState* jvmsp = jvms(); jvmsp != NULL; jvmsp = jvmsp->caller()) { 175 if (jvmsp->has_method() && jvmsp->method()->has_exception_handlers()) { 176 return true; 177 } 178 } 179 return false; 180 } 181 182 //------------------------------save_ex_oop------------------------------------ 183 // Save an exception without blowing stack contents or other JVM state. 184 void GraphKit::set_saved_ex_oop(SafePointNode* ex_map, Node* ex_oop) { 185 assert(!has_saved_ex_oop(ex_map), "clear ex-oop before setting again"); 186 ex_map->add_req(ex_oop); 187 debug_only(verify_exception_state(ex_map)); 188 } 189 190 inline static Node* common_saved_ex_oop(SafePointNode* ex_map, bool clear_it) { 191 assert(GraphKit::has_saved_ex_oop(ex_map), "ex_oop must be there"); 192 Node* ex_oop = ex_map->in(ex_map->req()-1); 193 if (clear_it) ex_map->del_req(ex_map->req()-1); 194 return ex_oop; 195 } 196 197 //-----------------------------saved_ex_oop------------------------------------ 198 // Recover a saved exception from its map. 199 Node* GraphKit::saved_ex_oop(SafePointNode* ex_map) { 200 return common_saved_ex_oop(ex_map, false); 201 } 202 203 //--------------------------clear_saved_ex_oop--------------------------------- 204 // Erase a previously saved exception from its map. 205 Node* GraphKit::clear_saved_ex_oop(SafePointNode* ex_map) { 206 return common_saved_ex_oop(ex_map, true); 207 } 208 209 #ifdef ASSERT 210 //---------------------------has_saved_ex_oop---------------------------------- 211 // Erase a previously saved exception from its map. 212 bool GraphKit::has_saved_ex_oop(SafePointNode* ex_map) { 213 return ex_map->req() == ex_map->jvms()->endoff()+1; 214 } 215 #endif 216 217 //-------------------------make_exception_state-------------------------------- 218 // Turn the current JVM state into an exception state, appending the ex_oop. 219 SafePointNode* GraphKit::make_exception_state(Node* ex_oop) { 220 sync_jvms(); 221 SafePointNode* ex_map = stop(); // do not manipulate this map any more 222 set_saved_ex_oop(ex_map, ex_oop); 223 return ex_map; 224 } 225 226 227 //--------------------------add_exception_state-------------------------------- 228 // Add an exception to my list of exceptions. 229 void GraphKit::add_exception_state(SafePointNode* ex_map) { 230 if (ex_map == NULL || ex_map->control() == top()) { 231 return; 232 } 233 #ifdef ASSERT 234 verify_exception_state(ex_map); 235 if (has_exceptions()) { 236 assert(ex_map->jvms()->same_calls_as(_exceptions->jvms()), "all collected exceptions must come from the same place"); 237 } 238 #endif 239 240 // If there is already an exception of exactly this type, merge with it. 241 // In particular, null-checks and other low-level exceptions common up here. 242 Node* ex_oop = saved_ex_oop(ex_map); 243 const Type* ex_type = _gvn.type(ex_oop); 244 if (ex_oop == top()) { 245 // No action needed. 246 return; 247 } 248 assert(ex_type->isa_instptr(), "exception must be an instance"); 249 for (SafePointNode* e2 = _exceptions; e2 != NULL; e2 = e2->next_exception()) { 250 const Type* ex_type2 = _gvn.type(saved_ex_oop(e2)); 251 // We check sp also because call bytecodes can generate exceptions 252 // both before and after arguments are popped! 253 if (ex_type2 == ex_type 254 && e2->_jvms->sp() == ex_map->_jvms->sp()) { 255 combine_exception_states(ex_map, e2); 256 return; 257 } 258 } 259 260 // No pre-existing exception of the same type. Chain it on the list. 261 push_exception_state(ex_map); 262 } 263 264 //-----------------------add_exception_states_from----------------------------- 265 void GraphKit::add_exception_states_from(JVMState* jvms) { 266 SafePointNode* ex_map = jvms->map()->next_exception(); 267 if (ex_map != NULL) { 268 jvms->map()->set_next_exception(NULL); 269 for (SafePointNode* next_map; ex_map != NULL; ex_map = next_map) { 270 next_map = ex_map->next_exception(); 271 ex_map->set_next_exception(NULL); 272 add_exception_state(ex_map); 273 } 274 } 275 } 276 277 //-----------------------transfer_exceptions_into_jvms------------------------- 278 JVMState* GraphKit::transfer_exceptions_into_jvms() { 279 if (map() == NULL) { 280 // We need a JVMS to carry the exceptions, but the map has gone away. 281 // Create a scratch JVMS, cloned from any of the exception states... 282 if (has_exceptions()) { 283 _map = _exceptions; 284 _map = clone_map(); 285 _map->set_next_exception(NULL); 286 clear_saved_ex_oop(_map); 287 debug_only(verify_map()); 288 } else { 289 // ...or created from scratch 290 JVMState* jvms = new (C) JVMState(_method, NULL); 291 jvms->set_bci(_bci); 292 jvms->set_sp(_sp); 293 jvms->set_map(new (C) SafePointNode(TypeFunc::Parms, jvms)); 294 set_jvms(jvms); 295 for (uint i = 0; i < map()->req(); i++) map()->init_req(i, top()); 296 set_all_memory(top()); 297 while (map()->req() < jvms->endoff()) map()->add_req(top()); 298 } 299 // (This is a kludge, in case you didn't notice.) 300 set_control(top()); 301 } 302 JVMState* jvms = sync_jvms(); 303 assert(!jvms->map()->has_exceptions(), "no exceptions on this map yet"); 304 jvms->map()->set_next_exception(_exceptions); 305 _exceptions = NULL; // done with this set of exceptions 306 return jvms; 307 } 308 309 static inline void add_n_reqs(Node* dstphi, Node* srcphi) { 310 assert(is_hidden_merge(dstphi), "must be a special merge node"); 311 assert(is_hidden_merge(srcphi), "must be a special merge node"); 312 uint limit = srcphi->req(); 313 for (uint i = PhiNode::Input; i < limit; i++) { 314 dstphi->add_req(srcphi->in(i)); 315 } 316 } 317 static inline void add_one_req(Node* dstphi, Node* src) { 318 assert(is_hidden_merge(dstphi), "must be a special merge node"); 319 assert(!is_hidden_merge(src), "must not be a special merge node"); 320 dstphi->add_req(src); 321 } 322 323 //-----------------------combine_exception_states------------------------------ 324 // This helper function combines exception states by building phis on a 325 // specially marked state-merging region. These regions and phis are 326 // untransformed, and can build up gradually. The region is marked by 327 // having a control input of its exception map, rather than NULL. Such 328 // regions do not appear except in this function, and in use_exception_state. 329 void GraphKit::combine_exception_states(SafePointNode* ex_map, SafePointNode* phi_map) { 330 if (failing()) return; // dying anyway... 331 JVMState* ex_jvms = ex_map->_jvms; 332 assert(ex_jvms->same_calls_as(phi_map->_jvms), "consistent call chains"); 333 assert(ex_jvms->stkoff() == phi_map->_jvms->stkoff(), "matching locals"); 334 assert(ex_jvms->sp() == phi_map->_jvms->sp(), "matching stack sizes"); 335 assert(ex_jvms->monoff() == phi_map->_jvms->monoff(), "matching JVMS"); 336 assert(ex_jvms->scloff() == phi_map->_jvms->scloff(), "matching scalar replaced objects"); 337 assert(ex_map->req() == phi_map->req(), "matching maps"); 338 uint tos = ex_jvms->stkoff() + ex_jvms->sp(); 339 Node* hidden_merge_mark = root(); 340 Node* region = phi_map->control(); 341 MergeMemNode* phi_mem = phi_map->merged_memory(); 342 MergeMemNode* ex_mem = ex_map->merged_memory(); 343 if (region->in(0) != hidden_merge_mark) { 344 // The control input is not (yet) a specially-marked region in phi_map. 345 // Make it so, and build some phis. 346 region = new (C) RegionNode(2); 347 _gvn.set_type(region, Type::CONTROL); 348 region->set_req(0, hidden_merge_mark); // marks an internal ex-state 349 region->init_req(1, phi_map->control()); 350 phi_map->set_control(region); 351 Node* io_phi = PhiNode::make(region, phi_map->i_o(), Type::ABIO); 352 record_for_igvn(io_phi); 353 _gvn.set_type(io_phi, Type::ABIO); 354 phi_map->set_i_o(io_phi); 355 for (MergeMemStream mms(phi_mem); mms.next_non_empty(); ) { 356 Node* m = mms.memory(); 357 Node* m_phi = PhiNode::make(region, m, Type::MEMORY, mms.adr_type(C)); 358 record_for_igvn(m_phi); 359 _gvn.set_type(m_phi, Type::MEMORY); 360 mms.set_memory(m_phi); 361 } 362 } 363 364 // Either or both of phi_map and ex_map might already be converted into phis. 365 Node* ex_control = ex_map->control(); 366 // if there is special marking on ex_map also, we add multiple edges from src 367 bool add_multiple = (ex_control->in(0) == hidden_merge_mark); 368 // how wide was the destination phi_map, originally? 369 uint orig_width = region->req(); 370 371 if (add_multiple) { 372 add_n_reqs(region, ex_control); 373 add_n_reqs(phi_map->i_o(), ex_map->i_o()); 374 } else { 375 // ex_map has no merges, so we just add single edges everywhere 376 add_one_req(region, ex_control); 377 add_one_req(phi_map->i_o(), ex_map->i_o()); 378 } 379 for (MergeMemStream mms(phi_mem, ex_mem); mms.next_non_empty2(); ) { 380 if (mms.is_empty()) { 381 // get a copy of the base memory, and patch some inputs into it 382 const TypePtr* adr_type = mms.adr_type(C); 383 Node* phi = mms.force_memory()->as_Phi()->slice_memory(adr_type); 384 assert(phi->as_Phi()->region() == mms.base_memory()->in(0), ""); 385 mms.set_memory(phi); 386 // Prepare to append interesting stuff onto the newly sliced phi: 387 while (phi->req() > orig_width) phi->del_req(phi->req()-1); 388 } 389 // Append stuff from ex_map: 390 if (add_multiple) { 391 add_n_reqs(mms.memory(), mms.memory2()); 392 } else { 393 add_one_req(mms.memory(), mms.memory2()); 394 } 395 } 396 uint limit = ex_map->req(); 397 for (uint i = TypeFunc::Parms; i < limit; i++) { 398 // Skip everything in the JVMS after tos. (The ex_oop follows.) 399 if (i == tos) i = ex_jvms->monoff(); 400 Node* src = ex_map->in(i); 401 Node* dst = phi_map->in(i); 402 if (src != dst) { 403 PhiNode* phi; 404 if (dst->in(0) != region) { 405 dst = phi = PhiNode::make(region, dst, _gvn.type(dst)); 406 record_for_igvn(phi); 407 _gvn.set_type(phi, phi->type()); 408 phi_map->set_req(i, dst); 409 // Prepare to append interesting stuff onto the new phi: 410 while (dst->req() > orig_width) dst->del_req(dst->req()-1); 411 } else { 412 assert(dst->is_Phi(), "nobody else uses a hidden region"); 413 phi = dst->as_Phi(); 414 } 415 if (add_multiple && src->in(0) == ex_control) { 416 // Both are phis. 417 add_n_reqs(dst, src); 418 } else { 419 while (dst->req() < region->req()) add_one_req(dst, src); 420 } 421 const Type* srctype = _gvn.type(src); 422 if (phi->type() != srctype) { 423 const Type* dsttype = phi->type()->meet_speculative(srctype); 424 if (phi->type() != dsttype) { 425 phi->set_type(dsttype); 426 _gvn.set_type(phi, dsttype); 427 } 428 } 429 } 430 } 431 phi_map->merge_replaced_nodes_with(ex_map); 432 } 433 434 //--------------------------use_exception_state-------------------------------- 435 Node* GraphKit::use_exception_state(SafePointNode* phi_map) { 436 if (failing()) { stop(); return top(); } 437 Node* region = phi_map->control(); 438 Node* hidden_merge_mark = root(); 439 assert(phi_map->jvms()->map() == phi_map, "sanity: 1-1 relation"); 440 Node* ex_oop = clear_saved_ex_oop(phi_map); 441 if (region->in(0) == hidden_merge_mark) { 442 // Special marking for internal ex-states. Process the phis now. 443 region->set_req(0, region); // now it's an ordinary region 444 set_jvms(phi_map->jvms()); // ...so now we can use it as a map 445 // Note: Setting the jvms also sets the bci and sp. 446 set_control(_gvn.transform(region)); 447 uint tos = jvms()->stkoff() + sp(); 448 for (uint i = 1; i < tos; i++) { 449 Node* x = phi_map->in(i); 450 if (x->in(0) == region) { 451 assert(x->is_Phi(), "expected a special phi"); 452 phi_map->set_req(i, _gvn.transform(x)); 453 } 454 } 455 for (MergeMemStream mms(merged_memory()); mms.next_non_empty(); ) { 456 Node* x = mms.memory(); 457 if (x->in(0) == region) { 458 assert(x->is_Phi(), "nobody else uses a hidden region"); 459 mms.set_memory(_gvn.transform(x)); 460 } 461 } 462 if (ex_oop->in(0) == region) { 463 assert(ex_oop->is_Phi(), "expected a special phi"); 464 ex_oop = _gvn.transform(ex_oop); 465 } 466 } else { 467 set_jvms(phi_map->jvms()); 468 } 469 470 assert(!is_hidden_merge(phi_map->control()), "hidden ex. states cleared"); 471 assert(!is_hidden_merge(phi_map->i_o()), "hidden ex. states cleared"); 472 return ex_oop; 473 } 474 475 //---------------------------------java_bc------------------------------------- 476 Bytecodes::Code GraphKit::java_bc() const { 477 ciMethod* method = this->method(); 478 int bci = this->bci(); 479 if (method != NULL && bci != InvocationEntryBci) 480 return method->java_code_at_bci(bci); 481 else 482 return Bytecodes::_illegal; 483 } 484 485 void GraphKit::uncommon_trap_if_should_post_on_exceptions(Deoptimization::DeoptReason reason, 486 bool must_throw) { 487 // if the exception capability is set, then we will generate code 488 // to check the JavaThread.should_post_on_exceptions flag to see 489 // if we actually need to report exception events (for this 490 // thread). If we don't need to report exception events, we will 491 // take the normal fast path provided by add_exception_events. If 492 // exception event reporting is enabled for this thread, we will 493 // take the uncommon_trap in the BuildCutout below. 494 495 // first must access the should_post_on_exceptions_flag in this thread's JavaThread 496 Node* jthread = _gvn.transform(new (C) ThreadLocalNode()); 497 Node* adr = basic_plus_adr(top(), jthread, in_bytes(JavaThread::should_post_on_exceptions_flag_offset())); 498 Node* should_post_flag = make_load(control(), adr, TypeInt::INT, T_INT, Compile::AliasIdxRaw, MemNode::unordered); 499 500 // Test the should_post_on_exceptions_flag vs. 0 501 Node* chk = _gvn.transform( new (C) CmpINode(should_post_flag, intcon(0)) ); 502 Node* tst = _gvn.transform( new (C) BoolNode(chk, BoolTest::eq) ); 503 504 // Branch to slow_path if should_post_on_exceptions_flag was true 505 { BuildCutout unless(this, tst, PROB_MAX); 506 // Do not try anything fancy if we're notifying the VM on every throw. 507 // Cf. case Bytecodes::_athrow in parse2.cpp. 508 uncommon_trap(reason, Deoptimization::Action_none, 509 (ciKlass*)NULL, (char*)NULL, must_throw); 510 } 511 512 } 513 514 //------------------------------builtin_throw---------------------------------- 515 void GraphKit::builtin_throw(Deoptimization::DeoptReason reason, Node* arg) { 516 bool must_throw = true; 517 518 if (env()->jvmti_can_post_on_exceptions()) { 519 // check if we must post exception events, take uncommon trap if so 520 uncommon_trap_if_should_post_on_exceptions(reason, must_throw); 521 // here if should_post_on_exceptions is false 522 // continue on with the normal codegen 523 } 524 525 // If this particular condition has not yet happened at this 526 // bytecode, then use the uncommon trap mechanism, and allow for 527 // a future recompilation if several traps occur here. 528 // If the throw is hot, try to use a more complicated inline mechanism 529 // which keeps execution inside the compiled code. 530 bool treat_throw_as_hot = false; 531 ciMethodData* md = method()->method_data(); 532 533 if (ProfileTraps) { 534 if (too_many_traps(reason)) { 535 treat_throw_as_hot = true; 536 } 537 // (If there is no MDO at all, assume it is early in 538 // execution, and that any deopts are part of the 539 // startup transient, and don't need to be remembered.) 540 541 // Also, if there is a local exception handler, treat all throws 542 // as hot if there has been at least one in this method. 543 if (C->trap_count(reason) != 0 544 && method()->method_data()->trap_count(reason) != 0 545 && has_ex_handler()) { 546 treat_throw_as_hot = true; 547 } 548 } 549 550 // If this throw happens frequently, an uncommon trap might cause 551 // a performance pothole. If there is a local exception handler, 552 // and if this particular bytecode appears to be deoptimizing often, 553 // let us handle the throw inline, with a preconstructed instance. 554 // Note: If the deopt count has blown up, the uncommon trap 555 // runtime is going to flush this nmethod, not matter what. 556 if (treat_throw_as_hot 557 && (!StackTraceInThrowable || OmitStackTraceInFastThrow)) { 558 // If the throw is local, we use a pre-existing instance and 559 // punt on the backtrace. This would lead to a missing backtrace 560 // (a repeat of 4292742) if the backtrace object is ever asked 561 // for its backtrace. 562 // Fixing this remaining case of 4292742 requires some flavor of 563 // escape analysis. Leave that for the future. 564 ciInstance* ex_obj = NULL; 565 switch (reason) { 566 case Deoptimization::Reason_null_check: 567 ex_obj = env()->NullPointerException_instance(); 568 break; 569 case Deoptimization::Reason_div0_check: 570 ex_obj = env()->ArithmeticException_instance(); 571 break; 572 case Deoptimization::Reason_range_check: 573 ex_obj = env()->ArrayIndexOutOfBoundsException_instance(); 574 break; 575 case Deoptimization::Reason_class_check: 576 if (java_bc() == Bytecodes::_aastore) { 577 ex_obj = env()->ArrayStoreException_instance(); 578 } else { 579 ex_obj = env()->ClassCastException_instance(); 580 } 581 break; 582 } 583 if (failing()) { stop(); return; } // exception allocation might fail 584 if (ex_obj != NULL) { 585 // Cheat with a preallocated exception object. 586 if (C->log() != NULL) 587 C->log()->elem("hot_throw preallocated='1' reason='%s'", 588 Deoptimization::trap_reason_name(reason)); 589 const TypeInstPtr* ex_con = TypeInstPtr::make(ex_obj); 590 Node* ex_node = _gvn.transform( ConNode::make(C, ex_con) ); 591 592 // Clear the detail message of the preallocated exception object. 593 // Weblogic sometimes mutates the detail message of exceptions 594 // using reflection. 595 int offset = java_lang_Throwable::get_detailMessage_offset(); 596 const TypePtr* adr_typ = ex_con->add_offset(offset); 597 598 Node *adr = basic_plus_adr(ex_node, ex_node, offset); 599 const TypeOopPtr* val_type = TypeOopPtr::make_from_klass(env()->String_klass()); 600 // Conservatively release stores of object references. 601 Node *store = store_oop_to_object(control(), ex_node, adr, adr_typ, null(), val_type, T_OBJECT, MemNode::release); 602 603 add_exception_state(make_exception_state(ex_node)); 604 return; 605 } 606 } 607 608 // %%% Maybe add entry to OptoRuntime which directly throws the exc.? 609 // It won't be much cheaper than bailing to the interp., since we'll 610 // have to pass up all the debug-info, and the runtime will have to 611 // create the stack trace. 612 613 // Usual case: Bail to interpreter. 614 // Reserve the right to recompile if we haven't seen anything yet. 615 616 assert(!Deoptimization::reason_is_speculate(reason), "unsupported"); 617 Deoptimization::DeoptAction action = Deoptimization::Action_maybe_recompile; 618 if (treat_throw_as_hot 619 && (method()->method_data()->trap_recompiled_at(bci(), NULL) 620 || C->too_many_traps(reason))) { 621 // We cannot afford to take more traps here. Suffer in the interpreter. 622 if (C->log() != NULL) 623 C->log()->elem("hot_throw preallocated='0' reason='%s' mcount='%d'", 624 Deoptimization::trap_reason_name(reason), 625 C->trap_count(reason)); 626 action = Deoptimization::Action_none; 627 } 628 629 // "must_throw" prunes the JVM state to include only the stack, if there 630 // are no local exception handlers. This should cut down on register 631 // allocation time and code size, by drastically reducing the number 632 // of in-edges on the call to the uncommon trap. 633 634 uncommon_trap(reason, action, (ciKlass*)NULL, (char*)NULL, must_throw); 635 } 636 637 638 //----------------------------PreserveJVMState--------------------------------- 639 PreserveJVMState::PreserveJVMState(GraphKit* kit, bool clone_map) { 640 debug_only(kit->verify_map()); 641 _kit = kit; 642 _map = kit->map(); // preserve the map 643 _sp = kit->sp(); 644 kit->set_map(clone_map ? kit->clone_map() : NULL); 645 #ifdef ASSERT 646 _bci = kit->bci(); 647 Parse* parser = kit->is_Parse(); 648 int block = (parser == NULL || parser->block() == NULL) ? -1 : parser->block()->rpo(); 649 _block = block; 650 #endif 651 } 652 PreserveJVMState::~PreserveJVMState() { 653 GraphKit* kit = _kit; 654 #ifdef ASSERT 655 assert(kit->bci() == _bci, "bci must not shift"); 656 Parse* parser = kit->is_Parse(); 657 int block = (parser == NULL || parser->block() == NULL) ? -1 : parser->block()->rpo(); 658 assert(block == _block, "block must not shift"); 659 #endif 660 kit->set_map(_map); 661 kit->set_sp(_sp); 662 } 663 664 665 //-----------------------------BuildCutout------------------------------------- 666 BuildCutout::BuildCutout(GraphKit* kit, Node* p, float prob, float cnt) 667 : PreserveJVMState(kit) 668 { 669 assert(p->is_Con() || p->is_Bool(), "test must be a bool"); 670 SafePointNode* outer_map = _map; // preserved map is caller's 671 SafePointNode* inner_map = kit->map(); 672 IfNode* iff = kit->create_and_map_if(outer_map->control(), p, prob, cnt); 673 outer_map->set_control(kit->gvn().transform( new (kit->C) IfTrueNode(iff) )); 674 inner_map->set_control(kit->gvn().transform( new (kit->C) IfFalseNode(iff) )); 675 } 676 BuildCutout::~BuildCutout() { 677 GraphKit* kit = _kit; 678 assert(kit->stopped(), "cutout code must stop, throw, return, etc."); 679 } 680 681 //---------------------------PreserveReexecuteState---------------------------- 682 PreserveReexecuteState::PreserveReexecuteState(GraphKit* kit) { 683 assert(!kit->stopped(), "must call stopped() before"); 684 _kit = kit; 685 _sp = kit->sp(); 686 _reexecute = kit->jvms()->_reexecute; 687 } 688 PreserveReexecuteState::~PreserveReexecuteState() { 689 if (_kit->stopped()) return; 690 _kit->jvms()->_reexecute = _reexecute; 691 _kit->set_sp(_sp); 692 } 693 694 //------------------------------clone_map-------------------------------------- 695 // Implementation of PreserveJVMState 696 // 697 // Only clone_map(...) here. If this function is only used in the 698 // PreserveJVMState class we may want to get rid of this extra 699 // function eventually and do it all there. 700 701 SafePointNode* GraphKit::clone_map() { 702 if (map() == NULL) return NULL; 703 704 // Clone the memory edge first 705 Node* mem = MergeMemNode::make(C, map()->memory()); 706 gvn().set_type_bottom(mem); 707 708 SafePointNode *clonemap = (SafePointNode*)map()->clone(); 709 JVMState* jvms = this->jvms(); 710 JVMState* clonejvms = jvms->clone_shallow(C); 711 clonemap->set_memory(mem); 712 clonemap->set_jvms(clonejvms); 713 clonejvms->set_map(clonemap); 714 record_for_igvn(clonemap); 715 gvn().set_type_bottom(clonemap); 716 return clonemap; 717 } 718 719 720 //-----------------------------set_map_clone----------------------------------- 721 void GraphKit::set_map_clone(SafePointNode* m) { 722 _map = m; 723 _map = clone_map(); 724 _map->set_next_exception(NULL); 725 debug_only(verify_map()); 726 } 727 728 729 //----------------------------kill_dead_locals--------------------------------- 730 // Detect any locals which are known to be dead, and force them to top. 731 void GraphKit::kill_dead_locals() { 732 // Consult the liveness information for the locals. If any 733 // of them are unused, then they can be replaced by top(). This 734 // should help register allocation time and cut down on the size 735 // of the deoptimization information. 736 737 // This call is made from many of the bytecode handling 738 // subroutines called from the Big Switch in do_one_bytecode. 739 // Every bytecode which might include a slow path is responsible 740 // for killing its dead locals. The more consistent we 741 // are about killing deads, the fewer useless phis will be 742 // constructed for them at various merge points. 743 744 // bci can be -1 (InvocationEntryBci). We return the entry 745 // liveness for the method. 746 747 if (method() == NULL || method()->code_size() == 0) { 748 // We are building a graph for a call to a native method. 749 // All locals are live. 750 return; 751 } 752 753 ResourceMark rm; 754 755 // Consult the liveness information for the locals. If any 756 // of them are unused, then they can be replaced by top(). This 757 // should help register allocation time and cut down on the size 758 // of the deoptimization information. 759 MethodLivenessResult live_locals = method()->liveness_at_bci(bci()); 760 761 int len = (int)live_locals.size(); 762 assert(len <= jvms()->loc_size(), "too many live locals"); 763 for (int local = 0; local < len; local++) { 764 if (!live_locals.at(local)) { 765 set_local(local, top()); 766 } 767 } 768 } 769 770 #ifdef ASSERT 771 //-------------------------dead_locals_are_killed------------------------------ 772 // Return true if all dead locals are set to top in the map. 773 // Used to assert "clean" debug info at various points. 774 bool GraphKit::dead_locals_are_killed() { 775 if (method() == NULL || method()->code_size() == 0) { 776 // No locals need to be dead, so all is as it should be. 777 return true; 778 } 779 780 // Make sure somebody called kill_dead_locals upstream. 781 ResourceMark rm; 782 for (JVMState* jvms = this->jvms(); jvms != NULL; jvms = jvms->caller()) { 783 if (jvms->loc_size() == 0) continue; // no locals to consult 784 SafePointNode* map = jvms->map(); 785 ciMethod* method = jvms->method(); 786 int bci = jvms->bci(); 787 if (jvms == this->jvms()) { 788 bci = this->bci(); // it might not yet be synched 789 } 790 MethodLivenessResult live_locals = method->liveness_at_bci(bci); 791 int len = (int)live_locals.size(); 792 if (!live_locals.is_valid() || len == 0) 793 // This method is trivial, or is poisoned by a breakpoint. 794 return true; 795 assert(len == jvms->loc_size(), "live map consistent with locals map"); 796 for (int local = 0; local < len; local++) { 797 if (!live_locals.at(local) && map->local(jvms, local) != top()) { 798 if (PrintMiscellaneous && (Verbose || WizardMode)) { 799 tty->print_cr("Zombie local %d: ", local); 800 jvms->dump(); 801 } 802 return false; 803 } 804 } 805 } 806 return true; 807 } 808 809 #endif //ASSERT 810 811 // Helper function for enforcing certain bytecodes to reexecute if 812 // deoptimization happens 813 static bool should_reexecute_implied_by_bytecode(JVMState *jvms, bool is_anewarray) { 814 ciMethod* cur_method = jvms->method(); 815 int cur_bci = jvms->bci(); 816 if (cur_method != NULL && cur_bci != InvocationEntryBci) { 817 Bytecodes::Code code = cur_method->java_code_at_bci(cur_bci); 818 return Interpreter::bytecode_should_reexecute(code) || 819 is_anewarray && code == Bytecodes::_multianewarray; 820 // Reexecute _multianewarray bytecode which was replaced with 821 // sequence of [a]newarray. See Parse::do_multianewarray(). 822 // 823 // Note: interpreter should not have it set since this optimization 824 // is limited by dimensions and guarded by flag so in some cases 825 // multianewarray() runtime calls will be generated and 826 // the bytecode should not be reexecutes (stack will not be reset). 827 } else 828 return false; 829 } 830 831 // Helper function for adding JVMState and debug information to node 832 void GraphKit::add_safepoint_edges(SafePointNode* call, bool must_throw) { 833 // Add the safepoint edges to the call (or other safepoint). 834 835 // Make sure dead locals are set to top. This 836 // should help register allocation time and cut down on the size 837 // of the deoptimization information. 838 assert(dead_locals_are_killed(), "garbage in debug info before safepoint"); 839 840 // Walk the inline list to fill in the correct set of JVMState's 841 // Also fill in the associated edges for each JVMState. 842 843 // If the bytecode needs to be reexecuted we need to put 844 // the arguments back on the stack. 845 const bool should_reexecute = jvms()->should_reexecute(); 846 JVMState* youngest_jvms = should_reexecute ? sync_jvms_for_reexecute() : sync_jvms(); 847 848 // NOTE: set_bci (called from sync_jvms) might reset the reexecute bit to 849 // undefined if the bci is different. This is normal for Parse but it 850 // should not happen for LibraryCallKit because only one bci is processed. 851 assert(!is_LibraryCallKit() || (jvms()->should_reexecute() == should_reexecute), 852 "in LibraryCallKit the reexecute bit should not change"); 853 854 // If we are guaranteed to throw, we can prune everything but the 855 // input to the current bytecode. 856 bool can_prune_locals = false; 857 uint stack_slots_not_pruned = 0; 858 int inputs = 0, depth = 0; 859 if (must_throw) { 860 assert(method() == youngest_jvms->method(), "sanity"); 861 if (compute_stack_effects(inputs, depth)) { 862 can_prune_locals = true; 863 stack_slots_not_pruned = inputs; 864 } 865 } 866 867 if (env()->jvmti_can_access_local_variables()) { 868 // At any safepoint, this method can get breakpointed, which would 869 // then require an immediate deoptimization. 870 can_prune_locals = false; // do not prune locals 871 stack_slots_not_pruned = 0; 872 } 873 874 // do not scribble on the input jvms 875 JVMState* out_jvms = youngest_jvms->clone_deep(C); 876 call->set_jvms(out_jvms); // Start jvms list for call node 877 878 // For a known set of bytecodes, the interpreter should reexecute them if 879 // deoptimization happens. We set the reexecute state for them here 880 if (out_jvms->is_reexecute_undefined() && //don't change if already specified 881 should_reexecute_implied_by_bytecode(out_jvms, call->is_AllocateArray())) { 882 out_jvms->set_should_reexecute(true); //NOTE: youngest_jvms not changed 883 } 884 885 // Presize the call: 886 DEBUG_ONLY(uint non_debug_edges = call->req()); 887 call->add_req_batch(top(), youngest_jvms->debug_depth()); 888 assert(call->req() == non_debug_edges + youngest_jvms->debug_depth(), ""); 889 890 // Set up edges so that the call looks like this: 891 // Call [state:] ctl io mem fptr retadr 892 // [parms:] parm0 ... parmN 893 // [root:] loc0 ... locN stk0 ... stkSP mon0 obj0 ... monN objN 894 // [...mid:] loc0 ... locN stk0 ... stkSP mon0 obj0 ... monN objN [...] 895 // [young:] loc0 ... locN stk0 ... stkSP mon0 obj0 ... monN objN 896 // Note that caller debug info precedes callee debug info. 897 898 // Fill pointer walks backwards from "young:" to "root:" in the diagram above: 899 uint debug_ptr = call->req(); 900 901 // Loop over the map input edges associated with jvms, add them 902 // to the call node, & reset all offsets to match call node array. 903 for (JVMState* in_jvms = youngest_jvms; in_jvms != NULL; ) { 904 uint debug_end = debug_ptr; 905 uint debug_start = debug_ptr - in_jvms->debug_size(); 906 debug_ptr = debug_start; // back up the ptr 907 908 uint p = debug_start; // walks forward in [debug_start, debug_end) 909 uint j, k, l; 910 SafePointNode* in_map = in_jvms->map(); 911 out_jvms->set_map(call); 912 913 if (can_prune_locals) { 914 assert(in_jvms->method() == out_jvms->method(), "sanity"); 915 // If the current throw can reach an exception handler in this JVMS, 916 // then we must keep everything live that can reach that handler. 917 // As a quick and dirty approximation, we look for any handlers at all. 918 if (in_jvms->method()->has_exception_handlers()) { 919 can_prune_locals = false; 920 } 921 } 922 923 // Add the Locals 924 k = in_jvms->locoff(); 925 l = in_jvms->loc_size(); 926 out_jvms->set_locoff(p); 927 if (!can_prune_locals) { 928 for (j = 0; j < l; j++) 929 call->set_req(p++, in_map->in(k+j)); 930 } else { 931 p += l; // already set to top above by add_req_batch 932 } 933 934 // Add the Expression Stack 935 k = in_jvms->stkoff(); 936 l = in_jvms->sp(); 937 out_jvms->set_stkoff(p); 938 if (!can_prune_locals) { 939 for (j = 0; j < l; j++) 940 call->set_req(p++, in_map->in(k+j)); 941 } else if (can_prune_locals && stack_slots_not_pruned != 0) { 942 // Divide stack into {S0,...,S1}, where S0 is set to top. 943 uint s1 = stack_slots_not_pruned; 944 stack_slots_not_pruned = 0; // for next iteration 945 if (s1 > l) s1 = l; 946 uint s0 = l - s1; 947 p += s0; // skip the tops preinstalled by add_req_batch 948 for (j = s0; j < l; j++) 949 call->set_req(p++, in_map->in(k+j)); 950 } else { 951 p += l; // already set to top above by add_req_batch 952 } 953 954 // Add the Monitors 955 k = in_jvms->monoff(); 956 l = in_jvms->mon_size(); 957 out_jvms->set_monoff(p); 958 for (j = 0; j < l; j++) 959 call->set_req(p++, in_map->in(k+j)); 960 961 // Copy any scalar object fields. 962 k = in_jvms->scloff(); 963 l = in_jvms->scl_size(); 964 out_jvms->set_scloff(p); 965 for (j = 0; j < l; j++) 966 call->set_req(p++, in_map->in(k+j)); 967 968 // Finish the new jvms. 969 out_jvms->set_endoff(p); 970 971 assert(out_jvms->endoff() == debug_end, "fill ptr must match"); 972 assert(out_jvms->depth() == in_jvms->depth(), "depth must match"); 973 assert(out_jvms->loc_size() == in_jvms->loc_size(), "size must match"); 974 assert(out_jvms->mon_size() == in_jvms->mon_size(), "size must match"); 975 assert(out_jvms->scl_size() == in_jvms->scl_size(), "size must match"); 976 assert(out_jvms->debug_size() == in_jvms->debug_size(), "size must match"); 977 978 // Update the two tail pointers in parallel. 979 out_jvms = out_jvms->caller(); 980 in_jvms = in_jvms->caller(); 981 } 982 983 assert(debug_ptr == non_debug_edges, "debug info must fit exactly"); 984 985 // Test the correctness of JVMState::debug_xxx accessors: 986 assert(call->jvms()->debug_start() == non_debug_edges, ""); 987 assert(call->jvms()->debug_end() == call->req(), ""); 988 assert(call->jvms()->debug_depth() == call->req() - non_debug_edges, ""); 989 } 990 991 bool GraphKit::compute_stack_effects(int& inputs, int& depth) { 992 Bytecodes::Code code = java_bc(); 993 if (code == Bytecodes::_wide) { 994 code = method()->java_code_at_bci(bci() + 1); 995 } 996 997 BasicType rtype = T_ILLEGAL; 998 int rsize = 0; 999 1000 if (code != Bytecodes::_illegal) { 1001 depth = Bytecodes::depth(code); // checkcast=0, athrow=-1 1002 rtype = Bytecodes::result_type(code); // checkcast=P, athrow=V 1003 if (rtype < T_CONFLICT) 1004 rsize = type2size[rtype]; 1005 } 1006 1007 switch (code) { 1008 case Bytecodes::_illegal: 1009 return false; 1010 1011 case Bytecodes::_ldc: 1012 case Bytecodes::_ldc_w: 1013 case Bytecodes::_ldc2_w: 1014 inputs = 0; 1015 break; 1016 1017 case Bytecodes::_dup: inputs = 1; break; 1018 case Bytecodes::_dup_x1: inputs = 2; break; 1019 case Bytecodes::_dup_x2: inputs = 3; break; 1020 case Bytecodes::_dup2: inputs = 2; break; 1021 case Bytecodes::_dup2_x1: inputs = 3; break; 1022 case Bytecodes::_dup2_x2: inputs = 4; break; 1023 case Bytecodes::_swap: inputs = 2; break; 1024 case Bytecodes::_arraylength: inputs = 1; break; 1025 1026 case Bytecodes::_getstatic: 1027 case Bytecodes::_putstatic: 1028 case Bytecodes::_getfield: 1029 case Bytecodes::_putfield: 1030 { 1031 bool ignored_will_link; 1032 ciField* field = method()->get_field_at_bci(bci(), ignored_will_link); 1033 int size = field->type()->size(); 1034 bool is_get = (depth >= 0), is_static = (depth & 1); 1035 inputs = (is_static ? 0 : 1); 1036 if (is_get) { 1037 depth = size - inputs; 1038 } else { 1039 inputs += size; // putxxx pops the value from the stack 1040 depth = - inputs; 1041 } 1042 } 1043 break; 1044 1045 case Bytecodes::_invokevirtual: 1046 case Bytecodes::_invokespecial: 1047 case Bytecodes::_invokestatic: 1048 case Bytecodes::_invokedynamic: 1049 case Bytecodes::_invokeinterface: 1050 { 1051 bool ignored_will_link; 1052 ciSignature* declared_signature = NULL; 1053 ciMethod* ignored_callee = method()->get_method_at_bci(bci(), ignored_will_link, &declared_signature); 1054 assert(declared_signature != NULL, "cannot be null"); 1055 inputs = declared_signature->arg_size_for_bc(code); 1056 int size = declared_signature->return_type()->size(); 1057 depth = size - inputs; 1058 } 1059 break; 1060 1061 case Bytecodes::_multianewarray: 1062 { 1063 ciBytecodeStream iter(method()); 1064 iter.reset_to_bci(bci()); 1065 iter.next(); 1066 inputs = iter.get_dimensions(); 1067 assert(rsize == 1, ""); 1068 depth = rsize - inputs; 1069 } 1070 break; 1071 1072 case Bytecodes::_ireturn: 1073 case Bytecodes::_lreturn: 1074 case Bytecodes::_freturn: 1075 case Bytecodes::_dreturn: 1076 case Bytecodes::_areturn: 1077 assert(rsize = -depth, ""); 1078 inputs = rsize; 1079 break; 1080 1081 case Bytecodes::_jsr: 1082 case Bytecodes::_jsr_w: 1083 inputs = 0; 1084 depth = 1; // S.B. depth=1, not zero 1085 break; 1086 1087 default: 1088 // bytecode produces a typed result 1089 inputs = rsize - depth; 1090 assert(inputs >= 0, ""); 1091 break; 1092 } 1093 1094 #ifdef ASSERT 1095 // spot check 1096 int outputs = depth + inputs; 1097 assert(outputs >= 0, "sanity"); 1098 switch (code) { 1099 case Bytecodes::_checkcast: assert(inputs == 1 && outputs == 1, ""); break; 1100 case Bytecodes::_athrow: assert(inputs == 1 && outputs == 0, ""); break; 1101 case Bytecodes::_aload_0: assert(inputs == 0 && outputs == 1, ""); break; 1102 case Bytecodes::_return: assert(inputs == 0 && outputs == 0, ""); break; 1103 case Bytecodes::_drem: assert(inputs == 4 && outputs == 2, ""); break; 1104 } 1105 #endif //ASSERT 1106 1107 return true; 1108 } 1109 1110 1111 1112 //------------------------------basic_plus_adr--------------------------------- 1113 Node* GraphKit::basic_plus_adr(Node* base, Node* ptr, Node* offset) { 1114 // short-circuit a common case 1115 if (offset == intcon(0)) return ptr; 1116 return _gvn.transform( new (C) AddPNode(base, ptr, offset) ); 1117 } 1118 1119 Node* GraphKit::ConvI2L(Node* offset) { 1120 // short-circuit a common case 1121 jint offset_con = find_int_con(offset, Type::OffsetBot); 1122 if (offset_con != Type::OffsetBot) { 1123 return longcon((jlong) offset_con); 1124 } 1125 return _gvn.transform( new (C) ConvI2LNode(offset)); 1126 } 1127 1128 Node* GraphKit::ConvI2UL(Node* offset) { 1129 juint offset_con = (juint) find_int_con(offset, Type::OffsetBot); 1130 if (offset_con != (juint) Type::OffsetBot) { 1131 return longcon((julong) offset_con); 1132 } 1133 Node* conv = _gvn.transform( new (C) ConvI2LNode(offset)); 1134 Node* mask = _gvn.transform( ConLNode::make(C, (julong) max_juint) ); 1135 return _gvn.transform( new (C) AndLNode(conv, mask) ); 1136 } 1137 1138 Node* GraphKit::ConvL2I(Node* offset) { 1139 // short-circuit a common case 1140 jlong offset_con = find_long_con(offset, (jlong)Type::OffsetBot); 1141 if (offset_con != (jlong)Type::OffsetBot) { 1142 return intcon((int) offset_con); 1143 } 1144 return _gvn.transform( new (C) ConvL2INode(offset)); 1145 } 1146 1147 //-------------------------load_object_klass----------------------------------- 1148 Node* GraphKit::load_object_klass(Node* obj) { 1149 // Special-case a fresh allocation to avoid building nodes: 1150 Node* akls = AllocateNode::Ideal_klass(obj, &_gvn); 1151 if (akls != NULL) return akls; 1152 Node* k_adr = basic_plus_adr(obj, oopDesc::klass_offset_in_bytes()); 1153 return _gvn.transform(LoadKlassNode::make(_gvn, NULL, immutable_memory(), k_adr, TypeInstPtr::KLASS)); 1154 } 1155 1156 //-------------------------load_array_length----------------------------------- 1157 Node* GraphKit::load_array_length(Node* array) { 1158 // Special-case a fresh allocation to avoid building nodes: 1159 AllocateArrayNode* alloc = AllocateArrayNode::Ideal_array_allocation(array, &_gvn); 1160 Node *alen; 1161 if (alloc == NULL) { 1162 Node *r_adr = basic_plus_adr(array, arrayOopDesc::length_offset_in_bytes()); 1163 alen = _gvn.transform( new (C) LoadRangeNode(0, immutable_memory(), r_adr, TypeInt::POS)); 1164 } else { 1165 alen = alloc->Ideal_length(); 1166 Node* ccast = alloc->make_ideal_length(_gvn.type(array)->is_oopptr(), &_gvn); 1167 if (ccast != alen) { 1168 alen = _gvn.transform(ccast); 1169 } 1170 } 1171 return alen; 1172 } 1173 1174 //------------------------------do_null_check---------------------------------- 1175 // Helper function to do a NULL pointer check. Returned value is 1176 // the incoming address with NULL casted away. You are allowed to use the 1177 // not-null value only if you are control dependent on the test. 1178 extern int explicit_null_checks_inserted, 1179 explicit_null_checks_elided; 1180 Node* GraphKit::null_check_common(Node* value, BasicType type, 1181 // optional arguments for variations: 1182 bool assert_null, 1183 Node* *null_control) { 1184 assert(!assert_null || null_control == NULL, "not both at once"); 1185 if (stopped()) return top(); 1186 if (!GenerateCompilerNullChecks && !assert_null && null_control == NULL) { 1187 // For some performance testing, we may wish to suppress null checking. 1188 value = cast_not_null(value); // Make it appear to be non-null (4962416). 1189 return value; 1190 } 1191 explicit_null_checks_inserted++; 1192 1193 // Construct NULL check 1194 Node *chk = NULL; 1195 switch(type) { 1196 case T_LONG : chk = new (C) CmpLNode(value, _gvn.zerocon(T_LONG)); break; 1197 case T_INT : chk = new (C) CmpINode(value, _gvn.intcon(0)); break; 1198 case T_ARRAY : // fall through 1199 type = T_OBJECT; // simplify further tests 1200 case T_OBJECT : { 1201 const Type *t = _gvn.type( value ); 1202 1203 const TypeOopPtr* tp = t->isa_oopptr(); 1204 if (tp != NULL && tp->klass() != NULL && !tp->klass()->is_loaded() 1205 // Only for do_null_check, not any of its siblings: 1206 && !assert_null && null_control == NULL) { 1207 // Usually, any field access or invocation on an unloaded oop type 1208 // will simply fail to link, since the statically linked class is 1209 // likely also to be unloaded. However, in -Xcomp mode, sometimes 1210 // the static class is loaded but the sharper oop type is not. 1211 // Rather than checking for this obscure case in lots of places, 1212 // we simply observe that a null check on an unloaded class 1213 // will always be followed by a nonsense operation, so we 1214 // can just issue the uncommon trap here. 1215 // Our access to the unloaded class will only be correct 1216 // after it has been loaded and initialized, which requires 1217 // a trip through the interpreter. 1218 #ifndef PRODUCT 1219 if (WizardMode) { tty->print("Null check of unloaded "); tp->klass()->print(); tty->cr(); } 1220 #endif 1221 uncommon_trap(Deoptimization::Reason_unloaded, 1222 Deoptimization::Action_reinterpret, 1223 tp->klass(), "!loaded"); 1224 return top(); 1225 } 1226 1227 if (assert_null) { 1228 // See if the type is contained in NULL_PTR. 1229 // If so, then the value is already null. 1230 if (t->higher_equal(TypePtr::NULL_PTR)) { 1231 explicit_null_checks_elided++; 1232 return value; // Elided null assert quickly! 1233 } 1234 } else { 1235 // See if mixing in the NULL pointer changes type. 1236 // If so, then the NULL pointer was not allowed in the original 1237 // type. In other words, "value" was not-null. 1238 if (t->meet(TypePtr::NULL_PTR) != t->remove_speculative()) { 1239 // same as: if (!TypePtr::NULL_PTR->higher_equal(t)) ... 1240 explicit_null_checks_elided++; 1241 return value; // Elided null check quickly! 1242 } 1243 } 1244 chk = new (C) CmpPNode( value, null() ); 1245 break; 1246 } 1247 1248 default: 1249 fatal(err_msg_res("unexpected type: %s", type2name(type))); 1250 } 1251 assert(chk != NULL, "sanity check"); 1252 chk = _gvn.transform(chk); 1253 1254 BoolTest::mask btest = assert_null ? BoolTest::eq : BoolTest::ne; 1255 BoolNode *btst = new (C) BoolNode( chk, btest); 1256 Node *tst = _gvn.transform( btst ); 1257 1258 //----------- 1259 // if peephole optimizations occurred, a prior test existed. 1260 // If a prior test existed, maybe it dominates as we can avoid this test. 1261 if (tst != btst && type == T_OBJECT) { 1262 // At this point we want to scan up the CFG to see if we can 1263 // find an identical test (and so avoid this test altogether). 1264 Node *cfg = control(); 1265 int depth = 0; 1266 while( depth < 16 ) { // Limit search depth for speed 1267 if( cfg->Opcode() == Op_IfTrue && 1268 cfg->in(0)->in(1) == tst ) { 1269 // Found prior test. Use "cast_not_null" to construct an identical 1270 // CastPP (and hence hash to) as already exists for the prior test. 1271 // Return that casted value. 1272 if (assert_null) { 1273 replace_in_map(value, null()); 1274 return null(); // do not issue the redundant test 1275 } 1276 Node *oldcontrol = control(); 1277 set_control(cfg); 1278 Node *res = cast_not_null(value); 1279 set_control(oldcontrol); 1280 explicit_null_checks_elided++; 1281 return res; 1282 } 1283 cfg = IfNode::up_one_dom(cfg, /*linear_only=*/ true); 1284 if (cfg == NULL) break; // Quit at region nodes 1285 depth++; 1286 } 1287 } 1288 1289 //----------- 1290 // Branch to failure if null 1291 float ok_prob = PROB_MAX; // a priori estimate: nulls never happen 1292 Deoptimization::DeoptReason reason; 1293 if (assert_null) 1294 reason = Deoptimization::Reason_null_assert; 1295 else if (type == T_OBJECT) 1296 reason = Deoptimization::Reason_null_check; 1297 else 1298 reason = Deoptimization::Reason_div0_check; 1299 1300 // %%% Since Reason_unhandled is not recorded on a per-bytecode basis, 1301 // ciMethodData::has_trap_at will return a conservative -1 if any 1302 // must-be-null assertion has failed. This could cause performance 1303 // problems for a method after its first do_null_assert failure. 1304 // Consider using 'Reason_class_check' instead? 1305 1306 // To cause an implicit null check, we set the not-null probability 1307 // to the maximum (PROB_MAX). For an explicit check the probability 1308 // is set to a smaller value. 1309 if (null_control != NULL || too_many_traps(reason)) { 1310 // probability is less likely 1311 ok_prob = PROB_LIKELY_MAG(3); 1312 } else if (!assert_null && 1313 (ImplicitNullCheckThreshold > 0) && 1314 method() != NULL && 1315 (method()->method_data()->trap_count(reason) 1316 >= (uint)ImplicitNullCheckThreshold)) { 1317 ok_prob = PROB_LIKELY_MAG(3); 1318 } 1319 1320 if (null_control != NULL) { 1321 IfNode* iff = create_and_map_if(control(), tst, ok_prob, COUNT_UNKNOWN); 1322 Node* null_true = _gvn.transform( new (C) IfFalseNode(iff)); 1323 set_control( _gvn.transform( new (C) IfTrueNode(iff))); 1324 if (null_true == top()) 1325 explicit_null_checks_elided++; 1326 (*null_control) = null_true; 1327 } else { 1328 BuildCutout unless(this, tst, ok_prob); 1329 // Check for optimizer eliding test at parse time 1330 if (stopped()) { 1331 // Failure not possible; do not bother making uncommon trap. 1332 explicit_null_checks_elided++; 1333 } else if (assert_null) { 1334 uncommon_trap(reason, 1335 Deoptimization::Action_make_not_entrant, 1336 NULL, "assert_null"); 1337 } else { 1338 replace_in_map(value, zerocon(type)); 1339 builtin_throw(reason); 1340 } 1341 } 1342 1343 // Must throw exception, fall-thru not possible? 1344 if (stopped()) { 1345 return top(); // No result 1346 } 1347 1348 if (assert_null) { 1349 // Cast obj to null on this path. 1350 replace_in_map(value, zerocon(type)); 1351 return zerocon(type); 1352 } 1353 1354 // Cast obj to not-null on this path, if there is no null_control. 1355 // (If there is a null_control, a non-null value may come back to haunt us.) 1356 if (type == T_OBJECT) { 1357 Node* cast = cast_not_null(value, false); 1358 if (null_control == NULL || (*null_control) == top()) 1359 replace_in_map(value, cast); 1360 value = cast; 1361 } 1362 1363 return value; 1364 } 1365 1366 1367 //------------------------------cast_not_null---------------------------------- 1368 // Cast obj to not-null on this path 1369 Node* GraphKit::cast_not_null(Node* obj, bool do_replace_in_map) { 1370 const Type *t = _gvn.type(obj); 1371 const Type *t_not_null = t->join_speculative(TypePtr::NOTNULL); 1372 // Object is already not-null? 1373 if( t == t_not_null ) return obj; 1374 1375 Node *cast = new (C) CastPPNode(obj,t_not_null); 1376 cast->init_req(0, control()); 1377 cast = _gvn.transform( cast ); 1378 1379 // Scan for instances of 'obj' in the current JVM mapping. 1380 // These instances are known to be not-null after the test. 1381 if (do_replace_in_map) 1382 replace_in_map(obj, cast); 1383 1384 return cast; // Return casted value 1385 } 1386 1387 1388 //--------------------------replace_in_map------------------------------------- 1389 void GraphKit::replace_in_map(Node* old, Node* neww) { 1390 if (old == neww) { 1391 return; 1392 } 1393 1394 map()->replace_edge(old, neww); 1395 1396 // Note: This operation potentially replaces any edge 1397 // on the map. This includes locals, stack, and monitors 1398 // of the current (innermost) JVM state. 1399 1400 // don't let inconsistent types from profiling escape this 1401 // method 1402 1403 const Type* told = _gvn.type(old); 1404 const Type* tnew = _gvn.type(neww); 1405 1406 if (!tnew->higher_equal(told)) { 1407 return; 1408 } 1409 1410 map()->record_replaced_node(old, neww); 1411 } 1412 1413 1414 //============================================================================= 1415 //--------------------------------memory--------------------------------------- 1416 Node* GraphKit::memory(uint alias_idx) { 1417 MergeMemNode* mem = merged_memory(); 1418 Node* p = mem->memory_at(alias_idx); 1419 _gvn.set_type(p, Type::MEMORY); // must be mapped 1420 return p; 1421 } 1422 1423 //-----------------------------reset_memory------------------------------------ 1424 Node* GraphKit::reset_memory() { 1425 Node* mem = map()->memory(); 1426 // do not use this node for any more parsing! 1427 debug_only( map()->set_memory((Node*)NULL) ); 1428 return _gvn.transform( mem ); 1429 } 1430 1431 //------------------------------set_all_memory--------------------------------- 1432 void GraphKit::set_all_memory(Node* newmem) { 1433 Node* mergemem = MergeMemNode::make(C, newmem); 1434 gvn().set_type_bottom(mergemem); 1435 map()->set_memory(mergemem); 1436 } 1437 1438 //------------------------------set_all_memory_call---------------------------- 1439 void GraphKit::set_all_memory_call(Node* call, bool separate_io_proj) { 1440 Node* newmem = _gvn.transform( new (C) ProjNode(call, TypeFunc::Memory, separate_io_proj) ); 1441 set_all_memory(newmem); 1442 } 1443 1444 //============================================================================= 1445 // 1446 // parser factory methods for MemNodes 1447 // 1448 // These are layered on top of the factory methods in LoadNode and StoreNode, 1449 // and integrate with the parser's memory state and _gvn engine. 1450 // 1451 1452 // factory methods in "int adr_idx" 1453 Node* GraphKit::make_load(Node* ctl, Node* adr, const Type* t, BasicType bt, 1454 int adr_idx, 1455 MemNode::MemOrd mo, 1456 LoadNode::ControlDependency control_dependency, 1457 bool require_atomic_access, 1458 bool unaligned, 1459 bool mismatched) { 1460 assert(adr_idx != Compile::AliasIdxTop, "use other make_load factory" ); 1461 const TypePtr* adr_type = NULL; // debug-mode-only argument 1462 debug_only(adr_type = C->get_adr_type(adr_idx)); 1463 Node* mem = memory(adr_idx); 1464 Node* ld; 1465 if (require_atomic_access && bt == T_LONG) { 1466 ld = LoadLNode::make_atomic(C, ctl, mem, adr, adr_type, t, mo, control_dependency); 1467 } else if (require_atomic_access && bt == T_DOUBLE) { 1468 ld = LoadDNode::make_atomic(C, ctl, mem, adr, adr_type, t, mo, control_dependency); 1469 } else { 1470 ld = LoadNode::make(_gvn, ctl, mem, adr, adr_type, t, bt, mo, control_dependency); 1471 } 1472 if (unaligned) { 1473 ld->as_Load()->set_unaligned_access(); 1474 } 1475 if (mismatched) { 1476 ld->as_Load()->set_mismatched_access(); 1477 } 1478 ld = _gvn.transform(ld); 1479 if ((bt == T_OBJECT) && C->do_escape_analysis() || C->eliminate_boxing()) { 1480 // Improve graph before escape analysis and boxing elimination. 1481 record_for_igvn(ld); 1482 } 1483 return ld; 1484 } 1485 1486 Node* GraphKit::store_to_memory(Node* ctl, Node* adr, Node *val, BasicType bt, 1487 int adr_idx, 1488 MemNode::MemOrd mo, 1489 bool require_atomic_access, 1490 bool unaligned, 1491 bool mismatched) { 1492 assert(adr_idx != Compile::AliasIdxTop, "use other store_to_memory factory" ); 1493 const TypePtr* adr_type = NULL; 1494 debug_only(adr_type = C->get_adr_type(adr_idx)); 1495 Node *mem = memory(adr_idx); 1496 Node* st; 1497 if (require_atomic_access && bt == T_LONG) { 1498 st = StoreLNode::make_atomic(C, ctl, mem, adr, adr_type, val, mo); 1499 } else if (require_atomic_access && bt == T_DOUBLE) { 1500 st = StoreDNode::make_atomic(C, ctl, mem, adr, adr_type, val, mo); 1501 } else { 1502 st = StoreNode::make(_gvn, ctl, mem, adr, adr_type, val, bt, mo); 1503 } 1504 if (unaligned) { 1505 st->as_Store()->set_unaligned_access(); 1506 } 1507 if (mismatched) { 1508 st->as_Store()->set_mismatched_access(); 1509 } 1510 st = _gvn.transform(st); 1511 set_memory(st, adr_idx); 1512 // Back-to-back stores can only remove intermediate store with DU info 1513 // so push on worklist for optimizer. 1514 if (mem->req() > MemNode::Address && adr == mem->in(MemNode::Address)) 1515 record_for_igvn(st); 1516 1517 return st; 1518 } 1519 1520 1521 void GraphKit::pre_barrier(bool do_load, 1522 Node* ctl, 1523 Node* obj, 1524 Node* adr, 1525 uint adr_idx, 1526 Node* val, 1527 const TypeOopPtr* val_type, 1528 Node* pre_val, 1529 BasicType bt) { 1530 1531 BarrierSet* bs = Universe::heap()->barrier_set(); 1532 set_control(ctl); 1533 switch (bs->kind()) { 1534 case BarrierSet::G1SATBCT: 1535 case BarrierSet::G1SATBCTLogging: 1536 g1_write_barrier_pre(do_load, obj, adr, adr_idx, val, val_type, pre_val, bt); 1537 break; 1538 1539 case BarrierSet::CardTableModRef: 1540 case BarrierSet::CardTableExtension: 1541 case BarrierSet::ModRef: 1542 break; 1543 1544 case BarrierSet::Other: 1545 default : 1546 ShouldNotReachHere(); 1547 1548 } 1549 } 1550 1551 bool GraphKit::can_move_pre_barrier() const { 1552 BarrierSet* bs = Universe::heap()->barrier_set(); 1553 switch (bs->kind()) { 1554 case BarrierSet::G1SATBCT: 1555 case BarrierSet::G1SATBCTLogging: 1556 return true; // Can move it if no safepoint 1557 1558 case BarrierSet::CardTableModRef: 1559 case BarrierSet::CardTableExtension: 1560 case BarrierSet::ModRef: 1561 return true; // There is no pre-barrier 1562 1563 case BarrierSet::Other: 1564 default : 1565 ShouldNotReachHere(); 1566 } 1567 return false; 1568 } 1569 1570 void GraphKit::post_barrier(Node* ctl, 1571 Node* store, 1572 Node* obj, 1573 Node* adr, 1574 uint adr_idx, 1575 Node* val, 1576 BasicType bt, 1577 bool use_precise) { 1578 BarrierSet* bs = Universe::heap()->barrier_set(); 1579 set_control(ctl); 1580 switch (bs->kind()) { 1581 case BarrierSet::G1SATBCT: 1582 case BarrierSet::G1SATBCTLogging: 1583 g1_write_barrier_post(store, obj, adr, adr_idx, val, bt, use_precise); 1584 break; 1585 1586 case BarrierSet::CardTableModRef: 1587 case BarrierSet::CardTableExtension: 1588 write_barrier_post(store, obj, adr, adr_idx, val, use_precise); 1589 break; 1590 1591 case BarrierSet::ModRef: 1592 break; 1593 1594 case BarrierSet::Other: 1595 default : 1596 ShouldNotReachHere(); 1597 1598 } 1599 } 1600 1601 Node* GraphKit::store_oop(Node* ctl, 1602 Node* obj, 1603 Node* adr, 1604 const TypePtr* adr_type, 1605 Node* val, 1606 const TypeOopPtr* val_type, 1607 BasicType bt, 1608 bool use_precise, 1609 MemNode::MemOrd mo, 1610 bool mismatched) { 1611 // Transformation of a value which could be NULL pointer (CastPP #NULL) 1612 // could be delayed during Parse (for example, in adjust_map_after_if()). 1613 // Execute transformation here to avoid barrier generation in such case. 1614 if (_gvn.type(val) == TypePtr::NULL_PTR) 1615 val = _gvn.makecon(TypePtr::NULL_PTR); 1616 1617 set_control(ctl); 1618 if (stopped()) return top(); // Dead path ? 1619 1620 assert(bt == T_OBJECT, "sanity"); 1621 assert(val != NULL, "not dead path"); 1622 uint adr_idx = C->get_alias_index(adr_type); 1623 assert(adr_idx != Compile::AliasIdxTop, "use other store_to_memory factory" ); 1624 1625 pre_barrier(true /* do_load */, 1626 control(), obj, adr, adr_idx, val, val_type, 1627 NULL /* pre_val */, 1628 bt); 1629 1630 Node* store = store_to_memory(control(), adr, val, bt, adr_idx, mo, mismatched); 1631 post_barrier(control(), store, obj, adr, adr_idx, val, bt, use_precise); 1632 return store; 1633 } 1634 1635 // Could be an array or object we don't know at compile time (unsafe ref.) 1636 Node* GraphKit::store_oop_to_unknown(Node* ctl, 1637 Node* obj, // containing obj 1638 Node* adr, // actual adress to store val at 1639 const TypePtr* adr_type, 1640 Node* val, 1641 BasicType bt, 1642 MemNode::MemOrd mo, 1643 bool mismatched) { 1644 Compile::AliasType* at = C->alias_type(adr_type); 1645 const TypeOopPtr* val_type = NULL; 1646 if (adr_type->isa_instptr()) { 1647 if (at->field() != NULL) { 1648 // known field. This code is a copy of the do_put_xxx logic. 1649 ciField* field = at->field(); 1650 if (!field->type()->is_loaded()) { 1651 val_type = TypeInstPtr::BOTTOM; 1652 } else { 1653 val_type = TypeOopPtr::make_from_klass(field->type()->as_klass()); 1654 } 1655 } 1656 } else if (adr_type->isa_aryptr()) { 1657 val_type = adr_type->is_aryptr()->elem()->make_oopptr(); 1658 } 1659 if (val_type == NULL) { 1660 val_type = TypeInstPtr::BOTTOM; 1661 } 1662 return store_oop(ctl, obj, adr, adr_type, val, val_type, bt, true, mo, mismatched); 1663 } 1664 1665 1666 //-------------------------array_element_address------------------------- 1667 Node* GraphKit::array_element_address(Node* ary, Node* idx, BasicType elembt, 1668 const TypeInt* sizetype, Node* ctrl) { 1669 uint shift = exact_log2(type2aelembytes(elembt)); 1670 uint header = arrayOopDesc::base_offset_in_bytes(elembt); 1671 1672 // short-circuit a common case (saves lots of confusing waste motion) 1673 jint idx_con = find_int_con(idx, -1); 1674 if (idx_con >= 0) { 1675 intptr_t offset = header + ((intptr_t)idx_con << shift); 1676 return basic_plus_adr(ary, offset); 1677 } 1678 1679 // must be correct type for alignment purposes 1680 Node* base = basic_plus_adr(ary, header); 1681 #ifdef _LP64 1682 // The scaled index operand to AddP must be a clean 64-bit value. 1683 // Java allows a 32-bit int to be incremented to a negative 1684 // value, which appears in a 64-bit register as a large 1685 // positive number. Using that large positive number as an 1686 // operand in pointer arithmetic has bad consequences. 1687 // On the other hand, 32-bit overflow is rare, and the possibility 1688 // can often be excluded, if we annotate the ConvI2L node with 1689 // a type assertion that its value is known to be a small positive 1690 // number. (The prior range check has ensured this.) 1691 // This assertion is used by ConvI2LNode::Ideal. 1692 int index_max = max_jint - 1; // array size is max_jint, index is one less 1693 if (sizetype != NULL) index_max = sizetype->_hi - 1; 1694 const TypeInt* iidxtype = TypeInt::make(0, index_max, Type::WidenMax); 1695 idx = C->constrained_convI2L(&_gvn, idx, iidxtype, ctrl); 1696 #endif 1697 Node* scale = _gvn.transform( new (C) LShiftXNode(idx, intcon(shift)) ); 1698 return basic_plus_adr(ary, base, scale); 1699 } 1700 1701 //-------------------------load_array_element------------------------- 1702 Node* GraphKit::load_array_element(Node* ctl, Node* ary, Node* idx, const TypeAryPtr* arytype) { 1703 const Type* elemtype = arytype->elem(); 1704 BasicType elembt = elemtype->array_element_basic_type(); 1705 Node* adr = array_element_address(ary, idx, elembt, arytype->size()); 1706 if (elembt == T_NARROWOOP) { 1707 elembt = T_OBJECT; // To satisfy switch in LoadNode::make() 1708 } 1709 Node* ld = make_load(ctl, adr, elemtype, elembt, arytype, MemNode::unordered); 1710 return ld; 1711 } 1712 1713 //-------------------------set_arguments_for_java_call------------------------- 1714 // Arguments (pre-popped from the stack) are taken from the JVMS. 1715 void GraphKit::set_arguments_for_java_call(CallJavaNode* call) { 1716 // Add the call arguments: 1717 uint nargs = call->method()->arg_size(); 1718 for (uint i = 0; i < nargs; i++) { 1719 Node* arg = argument(i); 1720 call->init_req(i + TypeFunc::Parms, arg); 1721 } 1722 } 1723 1724 //---------------------------set_edges_for_java_call--------------------------- 1725 // Connect a newly created call into the current JVMS. 1726 // A return value node (if any) is returned from set_edges_for_java_call. 1727 void GraphKit::set_edges_for_java_call(CallJavaNode* call, bool must_throw, bool separate_io_proj) { 1728 1729 // Add the predefined inputs: 1730 call->init_req( TypeFunc::Control, control() ); 1731 call->init_req( TypeFunc::I_O , i_o() ); 1732 call->init_req( TypeFunc::Memory , reset_memory() ); 1733 call->init_req( TypeFunc::FramePtr, frameptr() ); 1734 call->init_req( TypeFunc::ReturnAdr, top() ); 1735 1736 add_safepoint_edges(call, must_throw); 1737 1738 Node* xcall = _gvn.transform(call); 1739 1740 if (xcall == top()) { 1741 set_control(top()); 1742 return; 1743 } 1744 assert(xcall == call, "call identity is stable"); 1745 1746 // Re-use the current map to produce the result. 1747 1748 set_control(_gvn.transform(new (C) ProjNode(call, TypeFunc::Control))); 1749 set_i_o( _gvn.transform(new (C) ProjNode(call, TypeFunc::I_O , separate_io_proj))); 1750 set_all_memory_call(xcall, separate_io_proj); 1751 1752 //return xcall; // no need, caller already has it 1753 } 1754 1755 Node* GraphKit::set_results_for_java_call(CallJavaNode* call, bool separate_io_proj) { 1756 if (stopped()) return top(); // maybe the call folded up? 1757 1758 // Capture the return value, if any. 1759 Node* ret; 1760 if (call->method() == NULL || 1761 call->method()->return_type()->basic_type() == T_VOID) 1762 ret = top(); 1763 else ret = _gvn.transform(new (C) ProjNode(call, TypeFunc::Parms)); 1764 1765 // Note: Since any out-of-line call can produce an exception, 1766 // we always insert an I_O projection from the call into the result. 1767 1768 make_slow_call_ex(call, env()->Throwable_klass(), separate_io_proj); 1769 1770 if (separate_io_proj) { 1771 // The caller requested separate projections be used by the fall 1772 // through and exceptional paths, so replace the projections for 1773 // the fall through path. 1774 set_i_o(_gvn.transform( new (C) ProjNode(call, TypeFunc::I_O) )); 1775 set_all_memory(_gvn.transform( new (C) ProjNode(call, TypeFunc::Memory) )); 1776 } 1777 return ret; 1778 } 1779 1780 //--------------------set_predefined_input_for_runtime_call-------------------- 1781 // Reading and setting the memory state is way conservative here. 1782 // The real problem is that I am not doing real Type analysis on memory, 1783 // so I cannot distinguish card mark stores from other stores. Across a GC 1784 // point the Store Barrier and the card mark memory has to agree. I cannot 1785 // have a card mark store and its barrier split across the GC point from 1786 // either above or below. Here I get that to happen by reading ALL of memory. 1787 // A better answer would be to separate out card marks from other memory. 1788 // For now, return the input memory state, so that it can be reused 1789 // after the call, if this call has restricted memory effects. 1790 Node* GraphKit::set_predefined_input_for_runtime_call(SafePointNode* call) { 1791 // Set fixed predefined input arguments 1792 Node* memory = reset_memory(); 1793 call->init_req( TypeFunc::Control, control() ); 1794 call->init_req( TypeFunc::I_O, top() ); // does no i/o 1795 call->init_req( TypeFunc::Memory, memory ); // may gc ptrs 1796 call->init_req( TypeFunc::FramePtr, frameptr() ); 1797 call->init_req( TypeFunc::ReturnAdr, top() ); 1798 return memory; 1799 } 1800 1801 //-------------------set_predefined_output_for_runtime_call-------------------- 1802 // Set control and memory (not i_o) from the call. 1803 // If keep_mem is not NULL, use it for the output state, 1804 // except for the RawPtr output of the call, if hook_mem is TypeRawPtr::BOTTOM. 1805 // If hook_mem is NULL, this call produces no memory effects at all. 1806 // If hook_mem is a Java-visible memory slice (such as arraycopy operands), 1807 // then only that memory slice is taken from the call. 1808 // In the last case, we must put an appropriate memory barrier before 1809 // the call, so as to create the correct anti-dependencies on loads 1810 // preceding the call. 1811 void GraphKit::set_predefined_output_for_runtime_call(Node* call, 1812 Node* keep_mem, 1813 const TypePtr* hook_mem) { 1814 // no i/o 1815 set_control(_gvn.transform( new (C) ProjNode(call,TypeFunc::Control) )); 1816 if (keep_mem) { 1817 // First clone the existing memory state 1818 set_all_memory(keep_mem); 1819 if (hook_mem != NULL) { 1820 // Make memory for the call 1821 Node* mem = _gvn.transform( new (C) ProjNode(call, TypeFunc::Memory) ); 1822 // Set the RawPtr memory state only. This covers all the heap top/GC stuff 1823 // We also use hook_mem to extract specific effects from arraycopy stubs. 1824 set_memory(mem, hook_mem); 1825 } 1826 // ...else the call has NO memory effects. 1827 1828 // Make sure the call advertises its memory effects precisely. 1829 // This lets us build accurate anti-dependences in gcm.cpp. 1830 assert(C->alias_type(call->adr_type()) == C->alias_type(hook_mem), 1831 "call node must be constructed correctly"); 1832 } else { 1833 assert(hook_mem == NULL, ""); 1834 // This is not a "slow path" call; all memory comes from the call. 1835 set_all_memory_call(call); 1836 } 1837 } 1838 1839 1840 // Replace the call with the current state of the kit. 1841 void GraphKit::replace_call(CallNode* call, Node* result, bool do_replaced_nodes) { 1842 JVMState* ejvms = NULL; 1843 if (has_exceptions()) { 1844 ejvms = transfer_exceptions_into_jvms(); 1845 } 1846 1847 ReplacedNodes replaced_nodes = map()->replaced_nodes(); 1848 ReplacedNodes replaced_nodes_exception; 1849 Node* ex_ctl = top(); 1850 1851 SafePointNode* final_state = stop(); 1852 1853 // Find all the needed outputs of this call 1854 CallProjections callprojs; 1855 call->extract_projections(&callprojs, true); 1856 1857 Node* init_mem = call->in(TypeFunc::Memory); 1858 Node* final_mem = final_state->in(TypeFunc::Memory); 1859 Node* final_ctl = final_state->in(TypeFunc::Control); 1860 Node* final_io = final_state->in(TypeFunc::I_O); 1861 1862 // Replace all the old call edges with the edges from the inlining result 1863 if (callprojs.fallthrough_catchproj != NULL) { 1864 C->gvn_replace_by(callprojs.fallthrough_catchproj, final_ctl); 1865 } 1866 if (callprojs.fallthrough_memproj != NULL) { 1867 if (final_mem->is_MergeMem()) { 1868 // Parser's exits MergeMem was not transformed but may be optimized 1869 final_mem = _gvn.transform(final_mem); 1870 } 1871 C->gvn_replace_by(callprojs.fallthrough_memproj, final_mem); 1872 } 1873 if (callprojs.fallthrough_ioproj != NULL) { 1874 C->gvn_replace_by(callprojs.fallthrough_ioproj, final_io); 1875 } 1876 1877 // Replace the result with the new result if it exists and is used 1878 if (callprojs.resproj != NULL && result != NULL) { 1879 C->gvn_replace_by(callprojs.resproj, result); 1880 } 1881 1882 if (ejvms == NULL) { 1883 // No exception edges to simply kill off those paths 1884 if (callprojs.catchall_catchproj != NULL) { 1885 C->gvn_replace_by(callprojs.catchall_catchproj, C->top()); 1886 } 1887 if (callprojs.catchall_memproj != NULL) { 1888 C->gvn_replace_by(callprojs.catchall_memproj, C->top()); 1889 } 1890 if (callprojs.catchall_ioproj != NULL) { 1891 C->gvn_replace_by(callprojs.catchall_ioproj, C->top()); 1892 } 1893 // Replace the old exception object with top 1894 if (callprojs.exobj != NULL) { 1895 C->gvn_replace_by(callprojs.exobj, C->top()); 1896 } 1897 } else { 1898 GraphKit ekit(ejvms); 1899 1900 // Load my combined exception state into the kit, with all phis transformed: 1901 SafePointNode* ex_map = ekit.combine_and_pop_all_exception_states(); 1902 replaced_nodes_exception = ex_map->replaced_nodes(); 1903 1904 Node* ex_oop = ekit.use_exception_state(ex_map); 1905 1906 if (callprojs.catchall_catchproj != NULL) { 1907 C->gvn_replace_by(callprojs.catchall_catchproj, ekit.control()); 1908 ex_ctl = ekit.control(); 1909 } 1910 if (callprojs.catchall_memproj != NULL) { 1911 C->gvn_replace_by(callprojs.catchall_memproj, ekit.reset_memory()); 1912 } 1913 if (callprojs.catchall_ioproj != NULL) { 1914 C->gvn_replace_by(callprojs.catchall_ioproj, ekit.i_o()); 1915 } 1916 1917 // Replace the old exception object with the newly created one 1918 if (callprojs.exobj != NULL) { 1919 C->gvn_replace_by(callprojs.exobj, ex_oop); 1920 } 1921 } 1922 1923 // Disconnect the call from the graph 1924 call->disconnect_inputs(NULL, C); 1925 C->gvn_replace_by(call, C->top()); 1926 1927 // Clean up any MergeMems that feed other MergeMems since the 1928 // optimizer doesn't like that. 1929 if (final_mem->is_MergeMem()) { 1930 Node_List wl; 1931 for (SimpleDUIterator i(final_mem); i.has_next(); i.next()) { 1932 Node* m = i.get(); 1933 if (m->is_MergeMem() && !wl.contains(m)) { 1934 wl.push(m); 1935 } 1936 } 1937 while (wl.size() > 0) { 1938 _gvn.transform(wl.pop()); 1939 } 1940 } 1941 1942 if (callprojs.fallthrough_catchproj != NULL && !final_ctl->is_top() && do_replaced_nodes) { 1943 replaced_nodes.apply(C, final_ctl); 1944 } 1945 if (!ex_ctl->is_top() && do_replaced_nodes) { 1946 replaced_nodes_exception.apply(C, ex_ctl); 1947 } 1948 } 1949 1950 1951 //------------------------------increment_counter------------------------------ 1952 // for statistics: increment a VM counter by 1 1953 1954 void GraphKit::increment_counter(address counter_addr) { 1955 Node* adr1 = makecon(TypeRawPtr::make(counter_addr)); 1956 increment_counter(adr1); 1957 } 1958 1959 void GraphKit::increment_counter(Node* counter_addr) { 1960 int adr_type = Compile::AliasIdxRaw; 1961 Node* ctrl = control(); 1962 Node* cnt = make_load(ctrl, counter_addr, TypeInt::INT, T_INT, adr_type, MemNode::unordered); 1963 Node* incr = _gvn.transform(new (C) AddINode(cnt, _gvn.intcon(1))); 1964 store_to_memory(ctrl, counter_addr, incr, T_INT, adr_type, MemNode::unordered); 1965 } 1966 1967 1968 //------------------------------uncommon_trap---------------------------------- 1969 // Bail out to the interpreter in mid-method. Implemented by calling the 1970 // uncommon_trap blob. This helper function inserts a runtime call with the 1971 // right debug info. 1972 void GraphKit::uncommon_trap(int trap_request, 1973 ciKlass* klass, const char* comment, 1974 bool must_throw, 1975 bool keep_exact_action) { 1976 if (failing()) stop(); 1977 if (stopped()) return; // trap reachable? 1978 1979 // Note: If ProfileTraps is true, and if a deopt. actually 1980 // occurs here, the runtime will make sure an MDO exists. There is 1981 // no need to call method()->ensure_method_data() at this point. 1982 1983 // Set the stack pointer to the right value for reexecution: 1984 set_sp(reexecute_sp()); 1985 1986 #ifdef ASSERT 1987 if (!must_throw) { 1988 // Make sure the stack has at least enough depth to execute 1989 // the current bytecode. 1990 int inputs, ignored_depth; 1991 if (compute_stack_effects(inputs, ignored_depth)) { 1992 assert(sp() >= inputs, err_msg_res("must have enough JVMS stack to execute %s: sp=%d, inputs=%d", 1993 Bytecodes::name(java_bc()), sp(), inputs)); 1994 } 1995 } 1996 #endif 1997 1998 Deoptimization::DeoptReason reason = Deoptimization::trap_request_reason(trap_request); 1999 Deoptimization::DeoptAction action = Deoptimization::trap_request_action(trap_request); 2000 2001 switch (action) { 2002 case Deoptimization::Action_maybe_recompile: 2003 case Deoptimization::Action_reinterpret: 2004 // Temporary fix for 6529811 to allow virtual calls to be sure they 2005 // get the chance to go from mono->bi->mega 2006 if (!keep_exact_action && 2007 Deoptimization::trap_request_index(trap_request) < 0 && 2008 too_many_recompiles(reason)) { 2009 // This BCI is causing too many recompilations. 2010 if (C->log() != NULL) { 2011 C->log()->elem("observe that='trap_action_change' reason='%s' from='%s' to='none'", 2012 Deoptimization::trap_reason_name(reason), 2013 Deoptimization::trap_action_name(action)); 2014 } 2015 action = Deoptimization::Action_none; 2016 trap_request = Deoptimization::make_trap_request(reason, action); 2017 } else { 2018 C->set_trap_can_recompile(true); 2019 } 2020 break; 2021 case Deoptimization::Action_make_not_entrant: 2022 C->set_trap_can_recompile(true); 2023 break; 2024 #ifdef ASSERT 2025 case Deoptimization::Action_none: 2026 case Deoptimization::Action_make_not_compilable: 2027 break; 2028 default: 2029 fatal(err_msg_res("unknown action %d: %s", action, Deoptimization::trap_action_name(action))); 2030 break; 2031 #endif 2032 } 2033 2034 if (TraceOptoParse) { 2035 char buf[100]; 2036 tty->print_cr("Uncommon trap %s at bci:%d", 2037 Deoptimization::format_trap_request(buf, sizeof(buf), 2038 trap_request), bci()); 2039 } 2040 2041 CompileLog* log = C->log(); 2042 if (log != NULL) { 2043 int kid = (klass == NULL)? -1: log->identify(klass); 2044 log->begin_elem("uncommon_trap bci='%d'", bci()); 2045 char buf[100]; 2046 log->print(" %s", Deoptimization::format_trap_request(buf, sizeof(buf), 2047 trap_request)); 2048 if (kid >= 0) log->print(" klass='%d'", kid); 2049 if (comment != NULL) log->print(" comment='%s'", comment); 2050 log->end_elem(); 2051 } 2052 2053 // Make sure any guarding test views this path as very unlikely 2054 Node *i0 = control()->in(0); 2055 if (i0 != NULL && i0->is_If()) { // Found a guarding if test? 2056 IfNode *iff = i0->as_If(); 2057 float f = iff->_prob; // Get prob 2058 if (control()->Opcode() == Op_IfTrue) { 2059 if (f > PROB_UNLIKELY_MAG(4)) 2060 iff->_prob = PROB_MIN; 2061 } else { 2062 if (f < PROB_LIKELY_MAG(4)) 2063 iff->_prob = PROB_MAX; 2064 } 2065 } 2066 2067 // Clear out dead values from the debug info. 2068 kill_dead_locals(); 2069 2070 // Now insert the uncommon trap subroutine call 2071 address call_addr = SharedRuntime::uncommon_trap_blob()->entry_point(); 2072 const TypePtr* no_memory_effects = NULL; 2073 // Pass the index of the class to be loaded 2074 Node* call = make_runtime_call(RC_NO_LEAF | RC_UNCOMMON | 2075 (must_throw ? RC_MUST_THROW : 0), 2076 OptoRuntime::uncommon_trap_Type(), 2077 call_addr, "uncommon_trap", no_memory_effects, 2078 intcon(trap_request)); 2079 assert(call->as_CallStaticJava()->uncommon_trap_request() == trap_request, 2080 "must extract request correctly from the graph"); 2081 assert(trap_request != 0, "zero value reserved by uncommon_trap_request"); 2082 2083 call->set_req(TypeFunc::ReturnAdr, returnadr()); 2084 // The debug info is the only real input to this call. 2085 2086 // Halt-and-catch fire here. The above call should never return! 2087 HaltNode* halt = new(C) HaltNode(control(), frameptr()); 2088 _gvn.set_type_bottom(halt); 2089 root()->add_req(halt); 2090 2091 stop_and_kill_map(); 2092 } 2093 2094 2095 //--------------------------just_allocated_object------------------------------ 2096 // Report the object that was just allocated. 2097 // It must be the case that there are no intervening safepoints. 2098 // We use this to determine if an object is so "fresh" that 2099 // it does not require card marks. 2100 Node* GraphKit::just_allocated_object(Node* current_control) { 2101 if (C->recent_alloc_ctl() == current_control) 2102 return C->recent_alloc_obj(); 2103 return NULL; 2104 } 2105 2106 2107 void GraphKit::round_double_arguments(ciMethod* dest_method) { 2108 // (Note: TypeFunc::make has a cache that makes this fast.) 2109 const TypeFunc* tf = TypeFunc::make(dest_method); 2110 int nargs = tf->_domain->_cnt - TypeFunc::Parms; 2111 for (int j = 0; j < nargs; j++) { 2112 const Type *targ = tf->_domain->field_at(j + TypeFunc::Parms); 2113 if( targ->basic_type() == T_DOUBLE ) { 2114 // If any parameters are doubles, they must be rounded before 2115 // the call, dstore_rounding does gvn.transform 2116 Node *arg = argument(j); 2117 arg = dstore_rounding(arg); 2118 set_argument(j, arg); 2119 } 2120 } 2121 } 2122 2123 /** 2124 * Record profiling data exact_kls for Node n with the type system so 2125 * that it can propagate it (speculation) 2126 * 2127 * @param n node that the type applies to 2128 * @param exact_kls type from profiling 2129 * 2130 * @return node with improved type 2131 */ 2132 Node* GraphKit::record_profile_for_speculation(Node* n, ciKlass* exact_kls) { 2133 const Type* current_type = _gvn.type(n); 2134 assert(UseTypeSpeculation, "type speculation must be on"); 2135 2136 const TypeOopPtr* speculative = current_type->speculative(); 2137 2138 if (current_type->would_improve_type(exact_kls, jvms()->depth())) { 2139 const TypeKlassPtr* tklass = TypeKlassPtr::make(exact_kls); 2140 const TypeOopPtr* xtype = tklass->as_instance_type(); 2141 assert(xtype->klass_is_exact(), "Should be exact"); 2142 // record the new speculative type's depth 2143 speculative = xtype->with_inline_depth(jvms()->depth()); 2144 } 2145 2146 if (speculative != current_type->speculative()) { 2147 // Build a type with a speculative type (what we think we know 2148 // about the type but will need a guard when we use it) 2149 const TypeOopPtr* spec_type = TypeOopPtr::make(TypePtr::BotPTR, Type::OffsetBot, TypeOopPtr::InstanceBot, speculative); 2150 // We're changing the type, we need a new CheckCast node to carry 2151 // the new type. The new type depends on the control: what 2152 // profiling tells us is only valid from here as far as we can 2153 // tell. 2154 Node* cast = new(C) CheckCastPPNode(control(), n, current_type->remove_speculative()->join_speculative(spec_type)); 2155 cast = _gvn.transform(cast); 2156 replace_in_map(n, cast); 2157 n = cast; 2158 } 2159 2160 return n; 2161 } 2162 2163 /** 2164 * Record profiling data from receiver profiling at an invoke with the 2165 * type system so that it can propagate it (speculation) 2166 * 2167 * @param n receiver node 2168 * 2169 * @return node with improved type 2170 */ 2171 Node* GraphKit::record_profiled_receiver_for_speculation(Node* n) { 2172 if (!UseTypeSpeculation) { 2173 return n; 2174 } 2175 ciKlass* exact_kls = profile_has_unique_klass(); 2176 return record_profile_for_speculation(n, exact_kls); 2177 } 2178 2179 /** 2180 * Record profiling data from argument profiling at an invoke with the 2181 * type system so that it can propagate it (speculation) 2182 * 2183 * @param dest_method target method for the call 2184 * @param bc what invoke bytecode is this? 2185 */ 2186 void GraphKit::record_profiled_arguments_for_speculation(ciMethod* dest_method, Bytecodes::Code bc) { 2187 if (!UseTypeSpeculation) { 2188 return; 2189 } 2190 const TypeFunc* tf = TypeFunc::make(dest_method); 2191 int nargs = tf->_domain->_cnt - TypeFunc::Parms; 2192 int skip = Bytecodes::has_receiver(bc) ? 1 : 0; 2193 for (int j = skip, i = 0; j < nargs && i < TypeProfileArgsLimit; j++) { 2194 const Type *targ = tf->_domain->field_at(j + TypeFunc::Parms); 2195 if (targ->basic_type() == T_OBJECT || targ->basic_type() == T_ARRAY) { 2196 ciKlass* better_type = method()->argument_profiled_type(bci(), i); 2197 if (better_type != NULL) { 2198 record_profile_for_speculation(argument(j), better_type); 2199 } 2200 i++; 2201 } 2202 } 2203 } 2204 2205 /** 2206 * Record profiling data from parameter profiling at an invoke with 2207 * the type system so that it can propagate it (speculation) 2208 */ 2209 void GraphKit::record_profiled_parameters_for_speculation() { 2210 if (!UseTypeSpeculation) { 2211 return; 2212 } 2213 for (int i = 0, j = 0; i < method()->arg_size() ; i++) { 2214 if (_gvn.type(local(i))->isa_oopptr()) { 2215 ciKlass* better_type = method()->parameter_profiled_type(j); 2216 if (better_type != NULL) { 2217 record_profile_for_speculation(local(i), better_type); 2218 } 2219 j++; 2220 } 2221 } 2222 } 2223 2224 void GraphKit::round_double_result(ciMethod* dest_method) { 2225 // A non-strict method may return a double value which has an extended 2226 // exponent, but this must not be visible in a caller which is 'strict' 2227 // If a strict caller invokes a non-strict callee, round a double result 2228 2229 BasicType result_type = dest_method->return_type()->basic_type(); 2230 assert( method() != NULL, "must have caller context"); 2231 if( result_type == T_DOUBLE && method()->is_strict() && !dest_method->is_strict() ) { 2232 // Destination method's return value is on top of stack 2233 // dstore_rounding() does gvn.transform 2234 Node *result = pop_pair(); 2235 result = dstore_rounding(result); 2236 push_pair(result); 2237 } 2238 } 2239 2240 // rounding for strict float precision conformance 2241 Node* GraphKit::precision_rounding(Node* n) { 2242 return UseStrictFP && _method->flags().is_strict() 2243 && UseSSE == 0 && Matcher::strict_fp_requires_explicit_rounding 2244 ? _gvn.transform( new (C) RoundFloatNode(0, n) ) 2245 : n; 2246 } 2247 2248 // rounding for strict double precision conformance 2249 Node* GraphKit::dprecision_rounding(Node *n) { 2250 return UseStrictFP && _method->flags().is_strict() 2251 && UseSSE <= 1 && Matcher::strict_fp_requires_explicit_rounding 2252 ? _gvn.transform( new (C) RoundDoubleNode(0, n) ) 2253 : n; 2254 } 2255 2256 // rounding for non-strict double stores 2257 Node* GraphKit::dstore_rounding(Node* n) { 2258 return Matcher::strict_fp_requires_explicit_rounding 2259 && UseSSE <= 1 2260 ? _gvn.transform( new (C) RoundDoubleNode(0, n) ) 2261 : n; 2262 } 2263 2264 //============================================================================= 2265 // Generate a fast path/slow path idiom. Graph looks like: 2266 // [foo] indicates that 'foo' is a parameter 2267 // 2268 // [in] NULL 2269 // \ / 2270 // CmpP 2271 // Bool ne 2272 // If 2273 // / \ 2274 // True False-<2> 2275 // / | 2276 // / cast_not_null 2277 // Load | | ^ 2278 // [fast_test] | | 2279 // gvn to opt_test | | 2280 // / \ | <1> 2281 // True False | 2282 // | \\ | 2283 // [slow_call] \[fast_result] 2284 // Ctl Val \ \ 2285 // | \ \ 2286 // Catch <1> \ \ 2287 // / \ ^ \ \ 2288 // Ex No_Ex | \ \ 2289 // | \ \ | \ <2> \ 2290 // ... \ [slow_res] | | \ [null_result] 2291 // \ \--+--+--- | | 2292 // \ | / \ | / 2293 // --------Region Phi 2294 // 2295 //============================================================================= 2296 // Code is structured as a series of driver functions all called 'do_XXX' that 2297 // call a set of helper functions. Helper functions first, then drivers. 2298 2299 //------------------------------null_check_oop--------------------------------- 2300 // Null check oop. Set null-path control into Region in slot 3. 2301 // Make a cast-not-nullness use the other not-null control. Return cast. 2302 Node* GraphKit::null_check_oop(Node* value, Node* *null_control, 2303 bool never_see_null, bool safe_for_replace) { 2304 // Initial NULL check taken path 2305 (*null_control) = top(); 2306 Node* cast = null_check_common(value, T_OBJECT, false, null_control); 2307 2308 // Generate uncommon_trap: 2309 if (never_see_null && (*null_control) != top()) { 2310 // If we see an unexpected null at a check-cast we record it and force a 2311 // recompile; the offending check-cast will be compiled to handle NULLs. 2312 // If we see more than one offending BCI, then all checkcasts in the 2313 // method will be compiled to handle NULLs. 2314 PreserveJVMState pjvms(this); 2315 set_control(*null_control); 2316 replace_in_map(value, null()); 2317 uncommon_trap(Deoptimization::Reason_null_check, 2318 Deoptimization::Action_make_not_entrant); 2319 (*null_control) = top(); // NULL path is dead 2320 } 2321 if ((*null_control) == top() && safe_for_replace) { 2322 replace_in_map(value, cast); 2323 } 2324 2325 // Cast away null-ness on the result 2326 return cast; 2327 } 2328 2329 //------------------------------opt_iff---------------------------------------- 2330 // Optimize the fast-check IfNode. Set the fast-path region slot 2. 2331 // Return slow-path control. 2332 Node* GraphKit::opt_iff(Node* region, Node* iff) { 2333 IfNode *opt_iff = _gvn.transform(iff)->as_If(); 2334 2335 // Fast path taken; set region slot 2 2336 Node *fast_taken = _gvn.transform( new (C) IfFalseNode(opt_iff) ); 2337 region->init_req(2,fast_taken); // Capture fast-control 2338 2339 // Fast path not-taken, i.e. slow path 2340 Node *slow_taken = _gvn.transform( new (C) IfTrueNode(opt_iff) ); 2341 return slow_taken; 2342 } 2343 2344 //-----------------------------make_runtime_call------------------------------- 2345 Node* GraphKit::make_runtime_call(int flags, 2346 const TypeFunc* call_type, address call_addr, 2347 const char* call_name, 2348 const TypePtr* adr_type, 2349 // The following parms are all optional. 2350 // The first NULL ends the list. 2351 Node* parm0, Node* parm1, 2352 Node* parm2, Node* parm3, 2353 Node* parm4, Node* parm5, 2354 Node* parm6, Node* parm7) { 2355 // Slow-path call 2356 bool is_leaf = !(flags & RC_NO_LEAF); 2357 bool has_io = (!is_leaf && !(flags & RC_NO_IO)); 2358 if (call_name == NULL) { 2359 assert(!is_leaf, "must supply name for leaf"); 2360 call_name = OptoRuntime::stub_name(call_addr); 2361 } 2362 CallNode* call; 2363 if (!is_leaf) { 2364 call = new(C) CallStaticJavaNode(call_type, call_addr, call_name, 2365 bci(), adr_type); 2366 } else if (flags & RC_NO_FP) { 2367 call = new(C) CallLeafNoFPNode(call_type, call_addr, call_name, adr_type); 2368 } else { 2369 call = new(C) CallLeafNode(call_type, call_addr, call_name, adr_type); 2370 } 2371 2372 // The following is similar to set_edges_for_java_call, 2373 // except that the memory effects of the call are restricted to AliasIdxRaw. 2374 2375 // Slow path call has no side-effects, uses few values 2376 bool wide_in = !(flags & RC_NARROW_MEM); 2377 bool wide_out = (C->get_alias_index(adr_type) == Compile::AliasIdxBot); 2378 2379 Node* prev_mem = NULL; 2380 if (wide_in) { 2381 prev_mem = set_predefined_input_for_runtime_call(call); 2382 } else { 2383 assert(!wide_out, "narrow in => narrow out"); 2384 Node* narrow_mem = memory(adr_type); 2385 prev_mem = reset_memory(); 2386 map()->set_memory(narrow_mem); 2387 set_predefined_input_for_runtime_call(call); 2388 } 2389 2390 // Hook each parm in order. Stop looking at the first NULL. 2391 if (parm0 != NULL) { call->init_req(TypeFunc::Parms+0, parm0); 2392 if (parm1 != NULL) { call->init_req(TypeFunc::Parms+1, parm1); 2393 if (parm2 != NULL) { call->init_req(TypeFunc::Parms+2, parm2); 2394 if (parm3 != NULL) { call->init_req(TypeFunc::Parms+3, parm3); 2395 if (parm4 != NULL) { call->init_req(TypeFunc::Parms+4, parm4); 2396 if (parm5 != NULL) { call->init_req(TypeFunc::Parms+5, parm5); 2397 if (parm6 != NULL) { call->init_req(TypeFunc::Parms+6, parm6); 2398 if (parm7 != NULL) { call->init_req(TypeFunc::Parms+7, parm7); 2399 /* close each nested if ===> */ } } } } } } } } 2400 assert(call->in(call->req()-1) != NULL, "must initialize all parms"); 2401 2402 if (!is_leaf) { 2403 // Non-leaves can block and take safepoints: 2404 add_safepoint_edges(call, ((flags & RC_MUST_THROW) != 0)); 2405 } 2406 // Non-leaves can throw exceptions: 2407 if (has_io) { 2408 call->set_req(TypeFunc::I_O, i_o()); 2409 } 2410 2411 if (flags & RC_UNCOMMON) { 2412 // Set the count to a tiny probability. Cf. Estimate_Block_Frequency. 2413 // (An "if" probability corresponds roughly to an unconditional count. 2414 // Sort of.) 2415 call->set_cnt(PROB_UNLIKELY_MAG(4)); 2416 } 2417 2418 Node* c = _gvn.transform(call); 2419 assert(c == call, "cannot disappear"); 2420 2421 if (wide_out) { 2422 // Slow path call has full side-effects. 2423 set_predefined_output_for_runtime_call(call); 2424 } else { 2425 // Slow path call has few side-effects, and/or sets few values. 2426 set_predefined_output_for_runtime_call(call, prev_mem, adr_type); 2427 } 2428 2429 if (has_io) { 2430 set_i_o(_gvn.transform(new (C) ProjNode(call, TypeFunc::I_O))); 2431 } 2432 return call; 2433 2434 } 2435 2436 //------------------------------merge_memory----------------------------------- 2437 // Merge memory from one path into the current memory state. 2438 void GraphKit::merge_memory(Node* new_mem, Node* region, int new_path) { 2439 for (MergeMemStream mms(merged_memory(), new_mem->as_MergeMem()); mms.next_non_empty2(); ) { 2440 Node* old_slice = mms.force_memory(); 2441 Node* new_slice = mms.memory2(); 2442 if (old_slice != new_slice) { 2443 PhiNode* phi; 2444 if (old_slice->is_Phi() && old_slice->as_Phi()->region() == region) { 2445 if (mms.is_empty()) { 2446 // clone base memory Phi's inputs for this memory slice 2447 assert(old_slice == mms.base_memory(), "sanity"); 2448 phi = PhiNode::make(region, NULL, Type::MEMORY, mms.adr_type(C)); 2449 _gvn.set_type(phi, Type::MEMORY); 2450 for (uint i = 1; i < phi->req(); i++) { 2451 phi->init_req(i, old_slice->in(i)); 2452 } 2453 } else { 2454 phi = old_slice->as_Phi(); // Phi was generated already 2455 } 2456 } else { 2457 phi = PhiNode::make(region, old_slice, Type::MEMORY, mms.adr_type(C)); 2458 _gvn.set_type(phi, Type::MEMORY); 2459 } 2460 phi->set_req(new_path, new_slice); 2461 mms.set_memory(phi); 2462 } 2463 } 2464 } 2465 2466 //------------------------------make_slow_call_ex------------------------------ 2467 // Make the exception handler hookups for the slow call 2468 void GraphKit::make_slow_call_ex(Node* call, ciInstanceKlass* ex_klass, bool separate_io_proj, bool deoptimize) { 2469 if (stopped()) return; 2470 2471 // Make a catch node with just two handlers: fall-through and catch-all 2472 Node* i_o = _gvn.transform( new (C) ProjNode(call, TypeFunc::I_O, separate_io_proj) ); 2473 Node* catc = _gvn.transform( new (C) CatchNode(control(), i_o, 2) ); 2474 Node* norm = _gvn.transform( new (C) CatchProjNode(catc, CatchProjNode::fall_through_index, CatchProjNode::no_handler_bci) ); 2475 Node* excp = _gvn.transform( new (C) CatchProjNode(catc, CatchProjNode::catch_all_index, CatchProjNode::no_handler_bci) ); 2476 2477 { PreserveJVMState pjvms(this); 2478 set_control(excp); 2479 set_i_o(i_o); 2480 2481 if (excp != top()) { 2482 if (deoptimize) { 2483 // Deoptimize if an exception is caught. Don't construct exception state in this case. 2484 uncommon_trap(Deoptimization::Reason_unhandled, 2485 Deoptimization::Action_none); 2486 } else { 2487 // Create an exception state also. 2488 // Use an exact type if the caller has specified a specific exception. 2489 const Type* ex_type = TypeOopPtr::make_from_klass_unique(ex_klass)->cast_to_ptr_type(TypePtr::NotNull); 2490 Node* ex_oop = new (C) CreateExNode(ex_type, control(), i_o); 2491 add_exception_state(make_exception_state(_gvn.transform(ex_oop))); 2492 } 2493 } 2494 } 2495 2496 // Get the no-exception control from the CatchNode. 2497 set_control(norm); 2498 } 2499 2500 2501 //-------------------------------gen_subtype_check----------------------------- 2502 // Generate a subtyping check. Takes as input the subtype and supertype. 2503 // Returns 2 values: sets the default control() to the true path and returns 2504 // the false path. Only reads invariant memory; sets no (visible) memory. 2505 // The PartialSubtypeCheckNode sets the hidden 1-word cache in the encoding 2506 // but that's not exposed to the optimizer. This call also doesn't take in an 2507 // Object; if you wish to check an Object you need to load the Object's class 2508 // prior to coming here. 2509 Node* GraphKit::gen_subtype_check(Node* subklass, Node* superklass) { 2510 // Fast check for identical types, perhaps identical constants. 2511 // The types can even be identical non-constants, in cases 2512 // involving Array.newInstance, Object.clone, etc. 2513 if (subklass == superklass) 2514 return top(); // false path is dead; no test needed. 2515 2516 if (_gvn.type(superklass)->singleton()) { 2517 ciKlass* superk = _gvn.type(superklass)->is_klassptr()->klass(); 2518 ciKlass* subk = _gvn.type(subklass)->is_klassptr()->klass(); 2519 2520 // In the common case of an exact superklass, try to fold up the 2521 // test before generating code. You may ask, why not just generate 2522 // the code and then let it fold up? The answer is that the generated 2523 // code will necessarily include null checks, which do not always 2524 // completely fold away. If they are also needless, then they turn 2525 // into a performance loss. Example: 2526 // Foo[] fa = blah(); Foo x = fa[0]; fa[1] = x; 2527 // Here, the type of 'fa' is often exact, so the store check 2528 // of fa[1]=x will fold up, without testing the nullness of x. 2529 switch (static_subtype_check(superk, subk)) { 2530 case SSC_always_false: 2531 { 2532 Node* always_fail = control(); 2533 set_control(top()); 2534 return always_fail; 2535 } 2536 case SSC_always_true: 2537 return top(); 2538 case SSC_easy_test: 2539 { 2540 // Just do a direct pointer compare and be done. 2541 Node* cmp = _gvn.transform( new(C) CmpPNode(subklass, superklass) ); 2542 Node* bol = _gvn.transform( new(C) BoolNode(cmp, BoolTest::eq) ); 2543 IfNode* iff = create_and_xform_if(control(), bol, PROB_STATIC_FREQUENT, COUNT_UNKNOWN); 2544 set_control( _gvn.transform( new(C) IfTrueNode (iff) ) ); 2545 return _gvn.transform( new(C) IfFalseNode(iff) ); 2546 } 2547 case SSC_full_test: 2548 break; 2549 default: 2550 ShouldNotReachHere(); 2551 } 2552 } 2553 2554 // %%% Possible further optimization: Even if the superklass is not exact, 2555 // if the subklass is the unique subtype of the superklass, the check 2556 // will always succeed. We could leave a dependency behind to ensure this. 2557 2558 // First load the super-klass's check-offset 2559 Node *p1 = basic_plus_adr( superklass, superklass, in_bytes(Klass::super_check_offset_offset()) ); 2560 Node *chk_off = _gvn.transform(new (C) LoadINode(NULL, memory(p1), p1, _gvn.type(p1)->is_ptr(), 2561 TypeInt::INT, MemNode::unordered)); 2562 int cacheoff_con = in_bytes(Klass::secondary_super_cache_offset()); 2563 bool might_be_cache = (find_int_con(chk_off, cacheoff_con) == cacheoff_con); 2564 2565 // Load from the sub-klass's super-class display list, or a 1-word cache of 2566 // the secondary superclass list, or a failing value with a sentinel offset 2567 // if the super-klass is an interface or exceptionally deep in the Java 2568 // hierarchy and we have to scan the secondary superclass list the hard way. 2569 // Worst-case type is a little odd: NULL is allowed as a result (usually 2570 // klass loads can never produce a NULL). 2571 Node *chk_off_X = ConvI2X(chk_off); 2572 Node *p2 = _gvn.transform( new (C) AddPNode(subklass,subklass,chk_off_X) ); 2573 // For some types like interfaces the following loadKlass is from a 1-word 2574 // cache which is mutable so can't use immutable memory. Other 2575 // types load from the super-class display table which is immutable. 2576 Node *kmem = might_be_cache ? memory(p2) : immutable_memory(); 2577 Node* nkls = _gvn.transform(LoadKlassNode::make(_gvn, NULL, kmem, p2, _gvn.type(p2)->is_ptr(), TypeKlassPtr::OBJECT_OR_NULL)); 2578 2579 // Compile speed common case: ARE a subtype and we canNOT fail 2580 if( superklass == nkls ) 2581 return top(); // false path is dead; no test needed. 2582 2583 // See if we get an immediate positive hit. Happens roughly 83% of the 2584 // time. Test to see if the value loaded just previously from the subklass 2585 // is exactly the superklass. 2586 Node *cmp1 = _gvn.transform( new (C) CmpPNode( superklass, nkls ) ); 2587 Node *bol1 = _gvn.transform( new (C) BoolNode( cmp1, BoolTest::eq ) ); 2588 IfNode *iff1 = create_and_xform_if( control(), bol1, PROB_LIKELY(0.83f), COUNT_UNKNOWN ); 2589 Node *iftrue1 = _gvn.transform( new (C) IfTrueNode ( iff1 ) ); 2590 set_control( _gvn.transform( new (C) IfFalseNode( iff1 ) ) ); 2591 2592 // Compile speed common case: Check for being deterministic right now. If 2593 // chk_off is a constant and not equal to cacheoff then we are NOT a 2594 // subklass. In this case we need exactly the 1 test above and we can 2595 // return those results immediately. 2596 if (!might_be_cache) { 2597 Node* not_subtype_ctrl = control(); 2598 set_control(iftrue1); // We need exactly the 1 test above 2599 return not_subtype_ctrl; 2600 } 2601 2602 // Gather the various success & failures here 2603 RegionNode *r_ok_subtype = new (C) RegionNode(4); 2604 record_for_igvn(r_ok_subtype); 2605 RegionNode *r_not_subtype = new (C) RegionNode(3); 2606 record_for_igvn(r_not_subtype); 2607 2608 r_ok_subtype->init_req(1, iftrue1); 2609 2610 // Check for immediate negative hit. Happens roughly 11% of the time (which 2611 // is roughly 63% of the remaining cases). Test to see if the loaded 2612 // check-offset points into the subklass display list or the 1-element 2613 // cache. If it points to the display (and NOT the cache) and the display 2614 // missed then it's not a subtype. 2615 Node *cacheoff = _gvn.intcon(cacheoff_con); 2616 Node *cmp2 = _gvn.transform( new (C) CmpINode( chk_off, cacheoff ) ); 2617 Node *bol2 = _gvn.transform( new (C) BoolNode( cmp2, BoolTest::ne ) ); 2618 IfNode *iff2 = create_and_xform_if( control(), bol2, PROB_LIKELY(0.63f), COUNT_UNKNOWN ); 2619 r_not_subtype->init_req(1, _gvn.transform( new (C) IfTrueNode (iff2) ) ); 2620 set_control( _gvn.transform( new (C) IfFalseNode(iff2) ) ); 2621 2622 // Check for self. Very rare to get here, but it is taken 1/3 the time. 2623 // No performance impact (too rare) but allows sharing of secondary arrays 2624 // which has some footprint reduction. 2625 Node *cmp3 = _gvn.transform( new (C) CmpPNode( subklass, superklass ) ); 2626 Node *bol3 = _gvn.transform( new (C) BoolNode( cmp3, BoolTest::eq ) ); 2627 IfNode *iff3 = create_and_xform_if( control(), bol3, PROB_LIKELY(0.36f), COUNT_UNKNOWN ); 2628 r_ok_subtype->init_req(2, _gvn.transform( new (C) IfTrueNode ( iff3 ) ) ); 2629 set_control( _gvn.transform( new (C) IfFalseNode( iff3 ) ) ); 2630 2631 // -- Roads not taken here: -- 2632 // We could also have chosen to perform the self-check at the beginning 2633 // of this code sequence, as the assembler does. This would not pay off 2634 // the same way, since the optimizer, unlike the assembler, can perform 2635 // static type analysis to fold away many successful self-checks. 2636 // Non-foldable self checks work better here in second position, because 2637 // the initial primary superclass check subsumes a self-check for most 2638 // types. An exception would be a secondary type like array-of-interface, 2639 // which does not appear in its own primary supertype display. 2640 // Finally, we could have chosen to move the self-check into the 2641 // PartialSubtypeCheckNode, and from there out-of-line in a platform 2642 // dependent manner. But it is worthwhile to have the check here, 2643 // where it can be perhaps be optimized. The cost in code space is 2644 // small (register compare, branch). 2645 2646 // Now do a linear scan of the secondary super-klass array. Again, no real 2647 // performance impact (too rare) but it's gotta be done. 2648 // Since the code is rarely used, there is no penalty for moving it 2649 // out of line, and it can only improve I-cache density. 2650 // The decision to inline or out-of-line this final check is platform 2651 // dependent, and is found in the AD file definition of PartialSubtypeCheck. 2652 Node* psc = _gvn.transform( 2653 new (C) PartialSubtypeCheckNode(control(), subklass, superklass) ); 2654 2655 Node *cmp4 = _gvn.transform( new (C) CmpPNode( psc, null() ) ); 2656 Node *bol4 = _gvn.transform( new (C) BoolNode( cmp4, BoolTest::ne ) ); 2657 IfNode *iff4 = create_and_xform_if( control(), bol4, PROB_FAIR, COUNT_UNKNOWN ); 2658 r_not_subtype->init_req(2, _gvn.transform( new (C) IfTrueNode (iff4) ) ); 2659 r_ok_subtype ->init_req(3, _gvn.transform( new (C) IfFalseNode(iff4) ) ); 2660 2661 // Return false path; set default control to true path. 2662 set_control( _gvn.transform(r_ok_subtype) ); 2663 return _gvn.transform(r_not_subtype); 2664 } 2665 2666 //----------------------------static_subtype_check----------------------------- 2667 // Shortcut important common cases when superklass is exact: 2668 // (0) superklass is java.lang.Object (can occur in reflective code) 2669 // (1) subklass is already limited to a subtype of superklass => always ok 2670 // (2) subklass does not overlap with superklass => always fail 2671 // (3) superklass has NO subtypes and we can check with a simple compare. 2672 int GraphKit::static_subtype_check(ciKlass* superk, ciKlass* subk) { 2673 if (StressReflectiveCode) { 2674 return SSC_full_test; // Let caller generate the general case. 2675 } 2676 2677 if (superk == env()->Object_klass()) { 2678 return SSC_always_true; // (0) this test cannot fail 2679 } 2680 2681 ciType* superelem = superk; 2682 if (superelem->is_array_klass()) 2683 superelem = superelem->as_array_klass()->base_element_type(); 2684 2685 if (!subk->is_interface()) { // cannot trust static interface types yet 2686 if (subk->is_subtype_of(superk)) { 2687 return SSC_always_true; // (1) false path dead; no dynamic test needed 2688 } 2689 if (!(superelem->is_klass() && superelem->as_klass()->is_interface()) && 2690 !superk->is_subtype_of(subk)) { 2691 return SSC_always_false; 2692 } 2693 } 2694 2695 // If casting to an instance klass, it must have no subtypes 2696 if (superk->is_interface()) { 2697 // Cannot trust interfaces yet. 2698 // %%% S.B. superk->nof_implementors() == 1 2699 } else if (superelem->is_instance_klass()) { 2700 ciInstanceKlass* ik = superelem->as_instance_klass(); 2701 if (!ik->has_subklass() && !ik->is_interface()) { 2702 if (!ik->is_final()) { 2703 // Add a dependency if there is a chance of a later subclass. 2704 C->dependencies()->assert_leaf_type(ik); 2705 } 2706 return SSC_easy_test; // (3) caller can do a simple ptr comparison 2707 } 2708 } else { 2709 // A primitive array type has no subtypes. 2710 return SSC_easy_test; // (3) caller can do a simple ptr comparison 2711 } 2712 2713 return SSC_full_test; 2714 } 2715 2716 // Profile-driven exact type check: 2717 Node* GraphKit::type_check_receiver(Node* receiver, ciKlass* klass, 2718 float prob, 2719 Node* *casted_receiver) { 2720 const TypeKlassPtr* tklass = TypeKlassPtr::make(klass); 2721 Node* recv_klass = load_object_klass(receiver); 2722 Node* want_klass = makecon(tklass); 2723 Node* cmp = _gvn.transform( new(C) CmpPNode(recv_klass, want_klass) ); 2724 Node* bol = _gvn.transform( new(C) BoolNode(cmp, BoolTest::eq) ); 2725 IfNode* iff = create_and_xform_if(control(), bol, prob, COUNT_UNKNOWN); 2726 set_control( _gvn.transform( new(C) IfTrueNode (iff) )); 2727 Node* fail = _gvn.transform( new(C) IfFalseNode(iff) ); 2728 2729 const TypeOopPtr* recv_xtype = tklass->as_instance_type(); 2730 assert(recv_xtype->klass_is_exact(), ""); 2731 2732 // Subsume downstream occurrences of receiver with a cast to 2733 // recv_xtype, since now we know what the type will be. 2734 Node* cast = new(C) CheckCastPPNode(control(), receiver, recv_xtype); 2735 (*casted_receiver) = _gvn.transform(cast); 2736 // (User must make the replace_in_map call.) 2737 2738 return fail; 2739 } 2740 2741 2742 //------------------------------seems_never_null------------------------------- 2743 // Use null_seen information if it is available from the profile. 2744 // If we see an unexpected null at a type check we record it and force a 2745 // recompile; the offending check will be recompiled to handle NULLs. 2746 // If we see several offending BCIs, then all checks in the 2747 // method will be recompiled. 2748 bool GraphKit::seems_never_null(Node* obj, ciProfileData* data) { 2749 if (UncommonNullCast // Cutout for this technique 2750 && obj != null() // And not the -Xcomp stupid case? 2751 && !too_many_traps(Deoptimization::Reason_null_check) 2752 ) { 2753 if (data == NULL) 2754 // Edge case: no mature data. Be optimistic here. 2755 return true; 2756 // If the profile has not seen a null, assume it won't happen. 2757 assert(java_bc() == Bytecodes::_checkcast || 2758 java_bc() == Bytecodes::_instanceof || 2759 java_bc() == Bytecodes::_aastore, "MDO must collect null_seen bit here"); 2760 return !data->as_BitData()->null_seen(); 2761 } 2762 return false; 2763 } 2764 2765 //------------------------maybe_cast_profiled_receiver------------------------- 2766 // If the profile has seen exactly one type, narrow to exactly that type. 2767 // Subsequent type checks will always fold up. 2768 Node* GraphKit::maybe_cast_profiled_receiver(Node* not_null_obj, 2769 ciKlass* require_klass, 2770 ciKlass* spec_klass, 2771 bool safe_for_replace) { 2772 if (!UseTypeProfile || !TypeProfileCasts) return NULL; 2773 2774 Deoptimization::DeoptReason reason = spec_klass == NULL ? Deoptimization::Reason_class_check : Deoptimization::Reason_speculate_class_check; 2775 2776 // Make sure we haven't already deoptimized from this tactic. 2777 if (too_many_traps(reason) || too_many_recompiles(reason)) 2778 return NULL; 2779 2780 // (No, this isn't a call, but it's enough like a virtual call 2781 // to use the same ciMethod accessor to get the profile info...) 2782 // If we have a speculative type use it instead of profiling (which 2783 // may not help us) 2784 ciKlass* exact_kls = spec_klass == NULL ? profile_has_unique_klass() : spec_klass; 2785 if (exact_kls != NULL) {// no cast failures here 2786 if (require_klass == NULL || 2787 static_subtype_check(require_klass, exact_kls) == SSC_always_true) { 2788 // If we narrow the type to match what the type profile sees or 2789 // the speculative type, we can then remove the rest of the 2790 // cast. 2791 // This is a win, even if the exact_kls is very specific, 2792 // because downstream operations, such as method calls, 2793 // will often benefit from the sharper type. 2794 Node* exact_obj = not_null_obj; // will get updated in place... 2795 Node* slow_ctl = type_check_receiver(exact_obj, exact_kls, 1.0, 2796 &exact_obj); 2797 { PreserveJVMState pjvms(this); 2798 set_control(slow_ctl); 2799 uncommon_trap_exact(reason, Deoptimization::Action_maybe_recompile); 2800 } 2801 if (safe_for_replace) { 2802 replace_in_map(not_null_obj, exact_obj); 2803 } 2804 return exact_obj; 2805 } 2806 // assert(ssc == SSC_always_true)... except maybe the profile lied to us. 2807 } 2808 2809 return NULL; 2810 } 2811 2812 /** 2813 * Cast obj to type and emit guard unless we had too many traps here 2814 * already 2815 * 2816 * @param obj node being casted 2817 * @param type type to cast the node to 2818 * @param not_null true if we know node cannot be null 2819 */ 2820 Node* GraphKit::maybe_cast_profiled_obj(Node* obj, 2821 ciKlass* type, 2822 bool not_null) { 2823 // type == NULL if profiling tells us this object is always null 2824 if (type != NULL) { 2825 Deoptimization::DeoptReason class_reason = Deoptimization::Reason_speculate_class_check; 2826 Deoptimization::DeoptReason null_reason = Deoptimization::Reason_null_check; 2827 if (!too_many_traps(null_reason) && !too_many_recompiles(null_reason) && 2828 !too_many_traps(class_reason) && !too_many_recompiles(class_reason)) { 2829 Node* not_null_obj = NULL; 2830 // not_null is true if we know the object is not null and 2831 // there's no need for a null check 2832 if (!not_null) { 2833 Node* null_ctl = top(); 2834 not_null_obj = null_check_oop(obj, &null_ctl, true, true); 2835 assert(null_ctl->is_top(), "no null control here"); 2836 } else { 2837 not_null_obj = obj; 2838 } 2839 2840 Node* exact_obj = not_null_obj; 2841 ciKlass* exact_kls = type; 2842 Node* slow_ctl = type_check_receiver(exact_obj, exact_kls, 1.0, 2843 &exact_obj); 2844 { 2845 PreserveJVMState pjvms(this); 2846 set_control(slow_ctl); 2847 uncommon_trap_exact(class_reason, Deoptimization::Action_maybe_recompile); 2848 } 2849 replace_in_map(not_null_obj, exact_obj); 2850 obj = exact_obj; 2851 } 2852 } else { 2853 if (!too_many_traps(Deoptimization::Reason_null_assert) && 2854 !too_many_recompiles(Deoptimization::Reason_null_assert)) { 2855 Node* exact_obj = null_assert(obj); 2856 replace_in_map(obj, exact_obj); 2857 obj = exact_obj; 2858 } 2859 } 2860 return obj; 2861 } 2862 2863 //-------------------------------gen_instanceof-------------------------------- 2864 // Generate an instance-of idiom. Used by both the instance-of bytecode 2865 // and the reflective instance-of call. 2866 Node* GraphKit::gen_instanceof(Node* obj, Node* superklass, bool safe_for_replace) { 2867 kill_dead_locals(); // Benefit all the uncommon traps 2868 assert( !stopped(), "dead parse path should be checked in callers" ); 2869 assert(!TypePtr::NULL_PTR->higher_equal(_gvn.type(superklass)->is_klassptr()), 2870 "must check for not-null not-dead klass in callers"); 2871 2872 // Make the merge point 2873 enum { _obj_path = 1, _fail_path, _null_path, PATH_LIMIT }; 2874 RegionNode* region = new(C) RegionNode(PATH_LIMIT); 2875 Node* phi = new(C) PhiNode(region, TypeInt::BOOL); 2876 C->set_has_split_ifs(true); // Has chance for split-if optimization 2877 2878 ciProfileData* data = NULL; 2879 if (java_bc() == Bytecodes::_instanceof) { // Only for the bytecode 2880 data = method()->method_data()->bci_to_data(bci()); 2881 } 2882 bool never_see_null = (ProfileDynamicTypes // aggressive use of profile 2883 && seems_never_null(obj, data)); 2884 2885 // Null check; get casted pointer; set region slot 3 2886 Node* null_ctl = top(); 2887 Node* not_null_obj = null_check_oop(obj, &null_ctl, never_see_null, safe_for_replace); 2888 2889 // If not_null_obj is dead, only null-path is taken 2890 if (stopped()) { // Doing instance-of on a NULL? 2891 set_control(null_ctl); 2892 return intcon(0); 2893 } 2894 region->init_req(_null_path, null_ctl); 2895 phi ->init_req(_null_path, intcon(0)); // Set null path value 2896 if (null_ctl == top()) { 2897 // Do this eagerly, so that pattern matches like is_diamond_phi 2898 // will work even during parsing. 2899 assert(_null_path == PATH_LIMIT-1, "delete last"); 2900 region->del_req(_null_path); 2901 phi ->del_req(_null_path); 2902 } 2903 2904 // Do we know the type check always succeed? 2905 bool known_statically = false; 2906 if (_gvn.type(superklass)->singleton()) { 2907 ciKlass* superk = _gvn.type(superklass)->is_klassptr()->klass(); 2908 ciKlass* subk = _gvn.type(obj)->is_oopptr()->klass(); 2909 if (subk != NULL && subk->is_loaded()) { 2910 int static_res = static_subtype_check(superk, subk); 2911 known_statically = (static_res == SSC_always_true || static_res == SSC_always_false); 2912 } 2913 } 2914 2915 if (known_statically && UseTypeSpeculation) { 2916 // If we know the type check always succeeds then we don't use the 2917 // profiling data at this bytecode. Don't lose it, feed it to the 2918 // type system as a speculative type. 2919 not_null_obj = record_profiled_receiver_for_speculation(not_null_obj); 2920 } else { 2921 const TypeOopPtr* obj_type = _gvn.type(obj)->is_oopptr(); 2922 // We may not have profiling here or it may not help us. If we 2923 // have a speculative type use it to perform an exact cast. 2924 ciKlass* spec_obj_type = obj_type->speculative_type(); 2925 if (spec_obj_type != NULL || (ProfileDynamicTypes && data != NULL)) { 2926 Node* cast_obj = maybe_cast_profiled_receiver(not_null_obj, NULL, spec_obj_type, safe_for_replace); 2927 if (stopped()) { // Profile disagrees with this path. 2928 set_control(null_ctl); // Null is the only remaining possibility. 2929 return intcon(0); 2930 } 2931 if (cast_obj != NULL) { 2932 not_null_obj = cast_obj; 2933 } 2934 } 2935 } 2936 2937 // Load the object's klass 2938 Node* obj_klass = load_object_klass(not_null_obj); 2939 2940 // Generate the subtype check 2941 Node* not_subtype_ctrl = gen_subtype_check(obj_klass, superklass); 2942 2943 // Plug in the success path to the general merge in slot 1. 2944 region->init_req(_obj_path, control()); 2945 phi ->init_req(_obj_path, intcon(1)); 2946 2947 // Plug in the failing path to the general merge in slot 2. 2948 region->init_req(_fail_path, not_subtype_ctrl); 2949 phi ->init_req(_fail_path, intcon(0)); 2950 2951 // Return final merged results 2952 set_control( _gvn.transform(region) ); 2953 record_for_igvn(region); 2954 return _gvn.transform(phi); 2955 } 2956 2957 //-------------------------------gen_checkcast--------------------------------- 2958 // Generate a checkcast idiom. Used by both the checkcast bytecode and the 2959 // array store bytecode. Stack must be as-if BEFORE doing the bytecode so the 2960 // uncommon-trap paths work. Adjust stack after this call. 2961 // If failure_control is supplied and not null, it is filled in with 2962 // the control edge for the cast failure. Otherwise, an appropriate 2963 // uncommon trap or exception is thrown. 2964 Node* GraphKit::gen_checkcast(Node *obj, Node* superklass, 2965 Node* *failure_control) { 2966 kill_dead_locals(); // Benefit all the uncommon traps 2967 const TypeKlassPtr *tk = _gvn.type(superklass)->is_klassptr(); 2968 const Type *toop = TypeOopPtr::make_from_klass(tk->klass()); 2969 2970 // Fast cutout: Check the case that the cast is vacuously true. 2971 // This detects the common cases where the test will short-circuit 2972 // away completely. We do this before we perform the null check, 2973 // because if the test is going to turn into zero code, we don't 2974 // want a residual null check left around. (Causes a slowdown, 2975 // for example, in some objArray manipulations, such as a[i]=a[j].) 2976 if (tk->singleton()) { 2977 const TypeOopPtr* objtp = _gvn.type(obj)->isa_oopptr(); 2978 if (objtp != NULL && objtp->klass() != NULL) { 2979 switch (static_subtype_check(tk->klass(), objtp->klass())) { 2980 case SSC_always_true: 2981 // If we know the type check always succeed then we don't use 2982 // the profiling data at this bytecode. Don't lose it, feed it 2983 // to the type system as a speculative type. 2984 return record_profiled_receiver_for_speculation(obj); 2985 case SSC_always_false: 2986 // It needs a null check because a null will *pass* the cast check. 2987 // A non-null value will always produce an exception. 2988 return null_assert(obj); 2989 } 2990 } 2991 } 2992 2993 ciProfileData* data = NULL; 2994 bool safe_for_replace = false; 2995 if (failure_control == NULL) { // use MDO in regular case only 2996 assert(java_bc() == Bytecodes::_aastore || 2997 java_bc() == Bytecodes::_checkcast, 2998 "interpreter profiles type checks only for these BCs"); 2999 data = method()->method_data()->bci_to_data(bci()); 3000 safe_for_replace = true; 3001 } 3002 3003 // Make the merge point 3004 enum { _obj_path = 1, _null_path, PATH_LIMIT }; 3005 RegionNode* region = new (C) RegionNode(PATH_LIMIT); 3006 Node* phi = new (C) PhiNode(region, toop); 3007 C->set_has_split_ifs(true); // Has chance for split-if optimization 3008 3009 // Use null-cast information if it is available 3010 bool never_see_null = ((failure_control == NULL) // regular case only 3011 && seems_never_null(obj, data)); 3012 3013 // Null check; get casted pointer; set region slot 3 3014 Node* null_ctl = top(); 3015 Node* not_null_obj = null_check_oop(obj, &null_ctl, never_see_null, safe_for_replace); 3016 3017 // If not_null_obj is dead, only null-path is taken 3018 if (stopped()) { // Doing instance-of on a NULL? 3019 set_control(null_ctl); 3020 return null(); 3021 } 3022 region->init_req(_null_path, null_ctl); 3023 phi ->init_req(_null_path, null()); // Set null path value 3024 if (null_ctl == top()) { 3025 // Do this eagerly, so that pattern matches like is_diamond_phi 3026 // will work even during parsing. 3027 assert(_null_path == PATH_LIMIT-1, "delete last"); 3028 region->del_req(_null_path); 3029 phi ->del_req(_null_path); 3030 } 3031 3032 Node* cast_obj = NULL; 3033 if (tk->klass_is_exact()) { 3034 // The following optimization tries to statically cast the speculative type of the object 3035 // (for example obtained during profiling) to the type of the superklass and then do a 3036 // dynamic check that the type of the object is what we expect. To work correctly 3037 // for checkcast and aastore the type of superklass should be exact. 3038 const TypeOopPtr* obj_type = _gvn.type(obj)->is_oopptr(); 3039 // We may not have profiling here or it may not help us. If we have 3040 // a speculative type use it to perform an exact cast. 3041 ciKlass* spec_obj_type = obj_type->speculative_type(); 3042 if (spec_obj_type != NULL || 3043 (data != NULL && 3044 // Counter has never been decremented (due to cast failure). 3045 // ...This is a reasonable thing to expect. It is true of 3046 // all casts inserted by javac to implement generic types. 3047 data->as_CounterData()->count() >= 0)) { 3048 cast_obj = maybe_cast_profiled_receiver(not_null_obj, tk->klass(), spec_obj_type, safe_for_replace); 3049 if (cast_obj != NULL) { 3050 if (failure_control != NULL) // failure is now impossible 3051 (*failure_control) = top(); 3052 // adjust the type of the phi to the exact klass: 3053 phi->raise_bottom_type(_gvn.type(cast_obj)->meet_speculative(TypePtr::NULL_PTR)); 3054 } 3055 } 3056 } 3057 3058 if (cast_obj == NULL) { 3059 // Load the object's klass 3060 Node* obj_klass = load_object_klass(not_null_obj); 3061 3062 // Generate the subtype check 3063 Node* not_subtype_ctrl = gen_subtype_check( obj_klass, superklass ); 3064 3065 // Plug in success path into the merge 3066 cast_obj = _gvn.transform(new (C) CheckCastPPNode(control(), 3067 not_null_obj, toop)); 3068 // Failure path ends in uncommon trap (or may be dead - failure impossible) 3069 if (failure_control == NULL) { 3070 if (not_subtype_ctrl != top()) { // If failure is possible 3071 PreserveJVMState pjvms(this); 3072 set_control(not_subtype_ctrl); 3073 builtin_throw(Deoptimization::Reason_class_check, obj_klass); 3074 } 3075 } else { 3076 (*failure_control) = not_subtype_ctrl; 3077 } 3078 } 3079 3080 region->init_req(_obj_path, control()); 3081 phi ->init_req(_obj_path, cast_obj); 3082 3083 // A merge of NULL or Casted-NotNull obj 3084 Node* res = _gvn.transform(phi); 3085 3086 // Note I do NOT always 'replace_in_map(obj,result)' here. 3087 // if( tk->klass()->can_be_primary_super() ) 3088 // This means that if I successfully store an Object into an array-of-String 3089 // I 'forget' that the Object is really now known to be a String. I have to 3090 // do this because we don't have true union types for interfaces - if I store 3091 // a Baz into an array-of-Interface and then tell the optimizer it's an 3092 // Interface, I forget that it's also a Baz and cannot do Baz-like field 3093 // references to it. FIX THIS WHEN UNION TYPES APPEAR! 3094 // replace_in_map( obj, res ); 3095 3096 // Return final merged results 3097 set_control( _gvn.transform(region) ); 3098 record_for_igvn(region); 3099 return res; 3100 } 3101 3102 //------------------------------next_monitor----------------------------------- 3103 // What number should be given to the next monitor? 3104 int GraphKit::next_monitor() { 3105 int current = jvms()->monitor_depth()* C->sync_stack_slots(); 3106 int next = current + C->sync_stack_slots(); 3107 // Keep the toplevel high water mark current: 3108 if (C->fixed_slots() < next) C->set_fixed_slots(next); 3109 return current; 3110 } 3111 3112 //------------------------------insert_mem_bar--------------------------------- 3113 // Memory barrier to avoid floating things around 3114 // The membar serves as a pinch point between both control and all memory slices. 3115 Node* GraphKit::insert_mem_bar(int opcode, Node* precedent) { 3116 MemBarNode* mb = MemBarNode::make(C, opcode, Compile::AliasIdxBot, precedent); 3117 mb->init_req(TypeFunc::Control, control()); 3118 mb->init_req(TypeFunc::Memory, reset_memory()); 3119 Node* membar = _gvn.transform(mb); 3120 set_control(_gvn.transform(new (C) ProjNode(membar, TypeFunc::Control))); 3121 set_all_memory_call(membar); 3122 return membar; 3123 } 3124 3125 //-------------------------insert_mem_bar_volatile---------------------------- 3126 // Memory barrier to avoid floating things around 3127 // The membar serves as a pinch point between both control and memory(alias_idx). 3128 // If you want to make a pinch point on all memory slices, do not use this 3129 // function (even with AliasIdxBot); use insert_mem_bar() instead. 3130 Node* GraphKit::insert_mem_bar_volatile(int opcode, int alias_idx, Node* precedent) { 3131 // When Parse::do_put_xxx updates a volatile field, it appends a series 3132 // of MemBarVolatile nodes, one for *each* volatile field alias category. 3133 // The first membar is on the same memory slice as the field store opcode. 3134 // This forces the membar to follow the store. (Bug 6500685 broke this.) 3135 // All the other membars (for other volatile slices, including AliasIdxBot, 3136 // which stands for all unknown volatile slices) are control-dependent 3137 // on the first membar. This prevents later volatile loads or stores 3138 // from sliding up past the just-emitted store. 3139 3140 MemBarNode* mb = MemBarNode::make(C, opcode, alias_idx, precedent); 3141 mb->set_req(TypeFunc::Control,control()); 3142 if (alias_idx == Compile::AliasIdxBot) { 3143 mb->set_req(TypeFunc::Memory, merged_memory()->base_memory()); 3144 } else { 3145 assert(!(opcode == Op_Initialize && alias_idx != Compile::AliasIdxRaw), "fix caller"); 3146 mb->set_req(TypeFunc::Memory, memory(alias_idx)); 3147 } 3148 Node* membar = _gvn.transform(mb); 3149 set_control(_gvn.transform(new (C) ProjNode(membar, TypeFunc::Control))); 3150 if (alias_idx == Compile::AliasIdxBot) { 3151 merged_memory()->set_base_memory(_gvn.transform(new (C) ProjNode(membar, TypeFunc::Memory))); 3152 } else { 3153 set_memory(_gvn.transform(new (C) ProjNode(membar, TypeFunc::Memory)),alias_idx); 3154 } 3155 return membar; 3156 } 3157 3158 //------------------------------shared_lock------------------------------------ 3159 // Emit locking code. 3160 FastLockNode* GraphKit::shared_lock(Node* obj) { 3161 // bci is either a monitorenter bc or InvocationEntryBci 3162 // %%% SynchronizationEntryBCI is redundant; use InvocationEntryBci in interfaces 3163 assert(SynchronizationEntryBCI == InvocationEntryBci, ""); 3164 3165 if( !GenerateSynchronizationCode ) 3166 return NULL; // Not locking things? 3167 if (stopped()) // Dead monitor? 3168 return NULL; 3169 3170 assert(dead_locals_are_killed(), "should kill locals before sync. point"); 3171 3172 // Box the stack location 3173 Node* box = _gvn.transform(new (C) BoxLockNode(next_monitor())); 3174 Node* mem = reset_memory(); 3175 3176 FastLockNode * flock = _gvn.transform(new (C) FastLockNode(0, obj, box) )->as_FastLock(); 3177 if (UseBiasedLocking && PrintPreciseBiasedLockingStatistics) { 3178 // Create the counters for this fast lock. 3179 flock->create_lock_counter(sync_jvms()); // sync_jvms used to get current bci 3180 } 3181 3182 // Create the rtm counters for this fast lock if needed. 3183 flock->create_rtm_lock_counter(sync_jvms()); // sync_jvms used to get current bci 3184 3185 // Add monitor to debug info for the slow path. If we block inside the 3186 // slow path and de-opt, we need the monitor hanging around 3187 map()->push_monitor( flock ); 3188 3189 const TypeFunc *tf = LockNode::lock_type(); 3190 LockNode *lock = new (C) LockNode(C, tf); 3191 3192 lock->init_req( TypeFunc::Control, control() ); 3193 lock->init_req( TypeFunc::Memory , mem ); 3194 lock->init_req( TypeFunc::I_O , top() ) ; // does no i/o 3195 lock->init_req( TypeFunc::FramePtr, frameptr() ); 3196 lock->init_req( TypeFunc::ReturnAdr, top() ); 3197 3198 lock->init_req(TypeFunc::Parms + 0, obj); 3199 lock->init_req(TypeFunc::Parms + 1, box); 3200 lock->init_req(TypeFunc::Parms + 2, flock); 3201 add_safepoint_edges(lock); 3202 3203 lock = _gvn.transform( lock )->as_Lock(); 3204 3205 // lock has no side-effects, sets few values 3206 set_predefined_output_for_runtime_call(lock, mem, TypeRawPtr::BOTTOM); 3207 3208 insert_mem_bar(Op_MemBarAcquireLock); 3209 3210 // Add this to the worklist so that the lock can be eliminated 3211 record_for_igvn(lock); 3212 3213 #ifndef PRODUCT 3214 if (PrintLockStatistics) { 3215 // Update the counter for this lock. Don't bother using an atomic 3216 // operation since we don't require absolute accuracy. 3217 lock->create_lock_counter(map()->jvms()); 3218 increment_counter(lock->counter()->addr()); 3219 } 3220 #endif 3221 3222 return flock; 3223 } 3224 3225 3226 //------------------------------shared_unlock---------------------------------- 3227 // Emit unlocking code. 3228 void GraphKit::shared_unlock(Node* box, Node* obj) { 3229 // bci is either a monitorenter bc or InvocationEntryBci 3230 // %%% SynchronizationEntryBCI is redundant; use InvocationEntryBci in interfaces 3231 assert(SynchronizationEntryBCI == InvocationEntryBci, ""); 3232 3233 if( !GenerateSynchronizationCode ) 3234 return; 3235 if (stopped()) { // Dead monitor? 3236 map()->pop_monitor(); // Kill monitor from debug info 3237 return; 3238 } 3239 3240 // Memory barrier to avoid floating things down past the locked region 3241 insert_mem_bar(Op_MemBarReleaseLock); 3242 3243 const TypeFunc *tf = OptoRuntime::complete_monitor_exit_Type(); 3244 UnlockNode *unlock = new (C) UnlockNode(C, tf); 3245 #ifdef ASSERT 3246 unlock->set_dbg_jvms(sync_jvms()); 3247 #endif 3248 uint raw_idx = Compile::AliasIdxRaw; 3249 unlock->init_req( TypeFunc::Control, control() ); 3250 unlock->init_req( TypeFunc::Memory , memory(raw_idx) ); 3251 unlock->init_req( TypeFunc::I_O , top() ) ; // does no i/o 3252 unlock->init_req( TypeFunc::FramePtr, frameptr() ); 3253 unlock->init_req( TypeFunc::ReturnAdr, top() ); 3254 3255 unlock->init_req(TypeFunc::Parms + 0, obj); 3256 unlock->init_req(TypeFunc::Parms + 1, box); 3257 unlock = _gvn.transform(unlock)->as_Unlock(); 3258 3259 Node* mem = reset_memory(); 3260 3261 // unlock has no side-effects, sets few values 3262 set_predefined_output_for_runtime_call(unlock, mem, TypeRawPtr::BOTTOM); 3263 3264 // Kill monitor from debug info 3265 map()->pop_monitor( ); 3266 } 3267 3268 //-------------------------------get_layout_helper----------------------------- 3269 // If the given klass is a constant or known to be an array, 3270 // fetch the constant layout helper value into constant_value 3271 // and return (Node*)NULL. Otherwise, load the non-constant 3272 // layout helper value, and return the node which represents it. 3273 // This two-faced routine is useful because allocation sites 3274 // almost always feature constant types. 3275 Node* GraphKit::get_layout_helper(Node* klass_node, jint& constant_value) { 3276 const TypeKlassPtr* inst_klass = _gvn.type(klass_node)->isa_klassptr(); 3277 if (!StressReflectiveCode && inst_klass != NULL) { 3278 ciKlass* klass = inst_klass->klass(); 3279 bool xklass = inst_klass->klass_is_exact(); 3280 if (xklass || klass->is_array_klass()) { 3281 jint lhelper = klass->layout_helper(); 3282 if (lhelper != Klass::_lh_neutral_value) { 3283 constant_value = lhelper; 3284 return (Node*) NULL; 3285 } 3286 } 3287 } 3288 constant_value = Klass::_lh_neutral_value; // put in a known value 3289 Node* lhp = basic_plus_adr(klass_node, klass_node, in_bytes(Klass::layout_helper_offset())); 3290 return make_load(NULL, lhp, TypeInt::INT, T_INT, MemNode::unordered); 3291 } 3292 3293 // We just put in an allocate/initialize with a big raw-memory effect. 3294 // Hook selected additional alias categories on the initialization. 3295 static void hook_memory_on_init(GraphKit& kit, int alias_idx, 3296 MergeMemNode* init_in_merge, 3297 Node* init_out_raw) { 3298 DEBUG_ONLY(Node* init_in_raw = init_in_merge->base_memory()); 3299 assert(init_in_merge->memory_at(alias_idx) == init_in_raw, ""); 3300 3301 Node* prevmem = kit.memory(alias_idx); 3302 init_in_merge->set_memory_at(alias_idx, prevmem); 3303 kit.set_memory(init_out_raw, alias_idx); 3304 } 3305 3306 //---------------------------set_output_for_allocation------------------------- 3307 Node* GraphKit::set_output_for_allocation(AllocateNode* alloc, 3308 const TypeOopPtr* oop_type, 3309 bool deoptimize_on_exception) { 3310 int rawidx = Compile::AliasIdxRaw; 3311 alloc->set_req( TypeFunc::FramePtr, frameptr() ); 3312 add_safepoint_edges(alloc); 3313 Node* allocx = _gvn.transform(alloc); 3314 set_control( _gvn.transform(new (C) ProjNode(allocx, TypeFunc::Control) ) ); 3315 // create memory projection for i_o 3316 set_memory ( _gvn.transform( new (C) ProjNode(allocx, TypeFunc::Memory, true) ), rawidx ); 3317 make_slow_call_ex(allocx, env()->Throwable_klass(), true, deoptimize_on_exception); 3318 3319 // create a memory projection as for the normal control path 3320 Node* malloc = _gvn.transform(new (C) ProjNode(allocx, TypeFunc::Memory)); 3321 set_memory(malloc, rawidx); 3322 3323 // a normal slow-call doesn't change i_o, but an allocation does 3324 // we create a separate i_o projection for the normal control path 3325 set_i_o(_gvn.transform( new (C) ProjNode(allocx, TypeFunc::I_O, false) ) ); 3326 Node* rawoop = _gvn.transform( new (C) ProjNode(allocx, TypeFunc::Parms) ); 3327 3328 // put in an initialization barrier 3329 InitializeNode* init = insert_mem_bar_volatile(Op_Initialize, rawidx, 3330 rawoop)->as_Initialize(); 3331 assert(alloc->initialization() == init, "2-way macro link must work"); 3332 assert(init ->allocation() == alloc, "2-way macro link must work"); 3333 { 3334 // Extract memory strands which may participate in the new object's 3335 // initialization, and source them from the new InitializeNode. 3336 // This will allow us to observe initializations when they occur, 3337 // and link them properly (as a group) to the InitializeNode. 3338 assert(init->in(InitializeNode::Memory) == malloc, ""); 3339 MergeMemNode* minit_in = MergeMemNode::make(C, malloc); 3340 init->set_req(InitializeNode::Memory, minit_in); 3341 record_for_igvn(minit_in); // fold it up later, if possible 3342 Node* minit_out = memory(rawidx); 3343 assert(minit_out->is_Proj() && minit_out->in(0) == init, ""); 3344 if (oop_type->isa_aryptr()) { 3345 const TypePtr* telemref = oop_type->add_offset(Type::OffsetBot); 3346 int elemidx = C->get_alias_index(telemref); 3347 hook_memory_on_init(*this, elemidx, minit_in, minit_out); 3348 } else if (oop_type->isa_instptr()) { 3349 ciInstanceKlass* ik = oop_type->klass()->as_instance_klass(); 3350 for (int i = 0, len = ik->nof_nonstatic_fields(); i < len; i++) { 3351 ciField* field = ik->nonstatic_field_at(i); 3352 if (field->offset() >= TrackedInitializationLimit * HeapWordSize) 3353 continue; // do not bother to track really large numbers of fields 3354 // Find (or create) the alias category for this field: 3355 int fieldidx = C->alias_type(field)->index(); 3356 hook_memory_on_init(*this, fieldidx, minit_in, minit_out); 3357 } 3358 } 3359 } 3360 3361 // Cast raw oop to the real thing... 3362 Node* javaoop = new (C) CheckCastPPNode(control(), rawoop, oop_type); 3363 javaoop = _gvn.transform(javaoop); 3364 C->set_recent_alloc(control(), javaoop); 3365 assert(just_allocated_object(control()) == javaoop, "just allocated"); 3366 3367 #ifdef ASSERT 3368 { // Verify that the AllocateNode::Ideal_allocation recognizers work: 3369 assert(AllocateNode::Ideal_allocation(rawoop, &_gvn) == alloc, 3370 "Ideal_allocation works"); 3371 assert(AllocateNode::Ideal_allocation(javaoop, &_gvn) == alloc, 3372 "Ideal_allocation works"); 3373 if (alloc->is_AllocateArray()) { 3374 assert(AllocateArrayNode::Ideal_array_allocation(rawoop, &_gvn) == alloc->as_AllocateArray(), 3375 "Ideal_allocation works"); 3376 assert(AllocateArrayNode::Ideal_array_allocation(javaoop, &_gvn) == alloc->as_AllocateArray(), 3377 "Ideal_allocation works"); 3378 } else { 3379 assert(alloc->in(AllocateNode::ALength)->is_top(), "no length, please"); 3380 } 3381 } 3382 #endif //ASSERT 3383 3384 return javaoop; 3385 } 3386 3387 //---------------------------new_instance-------------------------------------- 3388 // This routine takes a klass_node which may be constant (for a static type) 3389 // or may be non-constant (for reflective code). It will work equally well 3390 // for either, and the graph will fold nicely if the optimizer later reduces 3391 // the type to a constant. 3392 // The optional arguments are for specialized use by intrinsics: 3393 // - If 'extra_slow_test' if not null is an extra condition for the slow-path. 3394 // - If 'return_size_val', report the the total object size to the caller. 3395 // - deoptimize_on_exception controls how Java exceptions are handled (rethrow vs deoptimize) 3396 Node* GraphKit::new_instance(Node* klass_node, 3397 Node* extra_slow_test, 3398 Node* *return_size_val, 3399 bool deoptimize_on_exception) { 3400 // Compute size in doublewords 3401 // The size is always an integral number of doublewords, represented 3402 // as a positive bytewise size stored in the klass's layout_helper. 3403 // The layout_helper also encodes (in a low bit) the need for a slow path. 3404 jint layout_con = Klass::_lh_neutral_value; 3405 Node* layout_val = get_layout_helper(klass_node, layout_con); 3406 int layout_is_con = (layout_val == NULL); 3407 3408 if (extra_slow_test == NULL) extra_slow_test = intcon(0); 3409 // Generate the initial go-slow test. It's either ALWAYS (return a 3410 // Node for 1) or NEVER (return a NULL) or perhaps (in the reflective 3411 // case) a computed value derived from the layout_helper. 3412 Node* initial_slow_test = NULL; 3413 if (layout_is_con) { 3414 assert(!StressReflectiveCode, "stress mode does not use these paths"); 3415 bool must_go_slow = Klass::layout_helper_needs_slow_path(layout_con); 3416 initial_slow_test = must_go_slow? intcon(1): extra_slow_test; 3417 3418 } else { // reflective case 3419 // This reflective path is used by Unsafe.allocateInstance. 3420 // (It may be stress-tested by specifying StressReflectiveCode.) 3421 // Basically, we want to get into the VM is there's an illegal argument. 3422 Node* bit = intcon(Klass::_lh_instance_slow_path_bit); 3423 initial_slow_test = _gvn.transform( new (C) AndINode(layout_val, bit) ); 3424 if (extra_slow_test != intcon(0)) { 3425 initial_slow_test = _gvn.transform( new (C) OrINode(initial_slow_test, extra_slow_test) ); 3426 } 3427 // (Macro-expander will further convert this to a Bool, if necessary.) 3428 } 3429 3430 // Find the size in bytes. This is easy; it's the layout_helper. 3431 // The size value must be valid even if the slow path is taken. 3432 Node* size = NULL; 3433 if (layout_is_con) { 3434 size = MakeConX(Klass::layout_helper_size_in_bytes(layout_con)); 3435 } else { // reflective case 3436 // This reflective path is used by clone and Unsafe.allocateInstance. 3437 size = ConvI2X(layout_val); 3438 3439 // Clear the low bits to extract layout_helper_size_in_bytes: 3440 assert((int)Klass::_lh_instance_slow_path_bit < BytesPerLong, "clear bit"); 3441 Node* mask = MakeConX(~ (intptr_t)right_n_bits(LogBytesPerLong)); 3442 size = _gvn.transform( new (C) AndXNode(size, mask) ); 3443 } 3444 if (return_size_val != NULL) { 3445 (*return_size_val) = size; 3446 } 3447 3448 // This is a precise notnull oop of the klass. 3449 // (Actually, it need not be precise if this is a reflective allocation.) 3450 // It's what we cast the result to. 3451 const TypeKlassPtr* tklass = _gvn.type(klass_node)->isa_klassptr(); 3452 if (!tklass) tklass = TypeKlassPtr::OBJECT; 3453 const TypeOopPtr* oop_type = tklass->as_instance_type(); 3454 3455 // Now generate allocation code 3456 3457 // The entire memory state is needed for slow path of the allocation 3458 // since GC and deoptimization can happened. 3459 Node *mem = reset_memory(); 3460 set_all_memory(mem); // Create new memory state 3461 3462 AllocateNode* alloc 3463 = new (C) AllocateNode(C, AllocateNode::alloc_type(Type::TOP), 3464 control(), mem, i_o(), 3465 size, klass_node, 3466 initial_slow_test); 3467 3468 return set_output_for_allocation(alloc, oop_type, deoptimize_on_exception); 3469 } 3470 3471 //-------------------------------new_array------------------------------------- 3472 // helper for both newarray and anewarray 3473 // The 'length' parameter is (obviously) the length of the array. 3474 // See comments on new_instance for the meaning of the other arguments. 3475 Node* GraphKit::new_array(Node* klass_node, // array klass (maybe variable) 3476 Node* length, // number of array elements 3477 int nargs, // number of arguments to push back for uncommon trap 3478 Node* *return_size_val, 3479 bool deoptimize_on_exception) { 3480 jint layout_con = Klass::_lh_neutral_value; 3481 Node* layout_val = get_layout_helper(klass_node, layout_con); 3482 int layout_is_con = (layout_val == NULL); 3483 3484 if (!layout_is_con && !StressReflectiveCode && 3485 !too_many_traps(Deoptimization::Reason_class_check)) { 3486 // This is a reflective array creation site. 3487 // Optimistically assume that it is a subtype of Object[], 3488 // so that we can fold up all the address arithmetic. 3489 layout_con = Klass::array_layout_helper(T_OBJECT); 3490 Node* cmp_lh = _gvn.transform( new(C) CmpINode(layout_val, intcon(layout_con)) ); 3491 Node* bol_lh = _gvn.transform( new(C) BoolNode(cmp_lh, BoolTest::eq) ); 3492 { BuildCutout unless(this, bol_lh, PROB_MAX); 3493 inc_sp(nargs); 3494 uncommon_trap(Deoptimization::Reason_class_check, 3495 Deoptimization::Action_maybe_recompile); 3496 } 3497 layout_val = NULL; 3498 layout_is_con = true; 3499 } 3500 3501 // Generate the initial go-slow test. Make sure we do not overflow 3502 // if length is huge (near 2Gig) or negative! We do not need 3503 // exact double-words here, just a close approximation of needed 3504 // double-words. We can't add any offset or rounding bits, lest we 3505 // take a size -1 of bytes and make it positive. Use an unsigned 3506 // compare, so negative sizes look hugely positive. 3507 int fast_size_limit = FastAllocateSizeLimit; 3508 if (layout_is_con) { 3509 assert(!StressReflectiveCode, "stress mode does not use these paths"); 3510 // Increase the size limit if we have exact knowledge of array type. 3511 int log2_esize = Klass::layout_helper_log2_element_size(layout_con); 3512 fast_size_limit <<= (LogBytesPerLong - log2_esize); 3513 } 3514 3515 Node* initial_slow_cmp = _gvn.transform( new (C) CmpUNode( length, intcon( fast_size_limit ) ) ); 3516 Node* initial_slow_test = _gvn.transform( new (C) BoolNode( initial_slow_cmp, BoolTest::gt ) ); 3517 3518 // --- Size Computation --- 3519 // array_size = round_to_heap(array_header + (length << elem_shift)); 3520 // where round_to_heap(x) == round_to(x, MinObjAlignmentInBytes) 3521 // and round_to(x, y) == ((x + y-1) & ~(y-1)) 3522 // The rounding mask is strength-reduced, if possible. 3523 int round_mask = MinObjAlignmentInBytes - 1; 3524 Node* header_size = NULL; 3525 int header_size_min = arrayOopDesc::base_offset_in_bytes(T_BYTE); 3526 // (T_BYTE has the weakest alignment and size restrictions...) 3527 if (layout_is_con) { 3528 int hsize = Klass::layout_helper_header_size(layout_con); 3529 int eshift = Klass::layout_helper_log2_element_size(layout_con); 3530 BasicType etype = Klass::layout_helper_element_type(layout_con); 3531 if ((round_mask & ~right_n_bits(eshift)) == 0) 3532 round_mask = 0; // strength-reduce it if it goes away completely 3533 assert((hsize & right_n_bits(eshift)) == 0, "hsize is pre-rounded"); 3534 assert(header_size_min <= hsize, "generic minimum is smallest"); 3535 header_size_min = hsize; 3536 header_size = intcon(hsize + round_mask); 3537 } else { 3538 Node* hss = intcon(Klass::_lh_header_size_shift); 3539 Node* hsm = intcon(Klass::_lh_header_size_mask); 3540 Node* hsize = _gvn.transform( new(C) URShiftINode(layout_val, hss) ); 3541 hsize = _gvn.transform( new(C) AndINode(hsize, hsm) ); 3542 Node* mask = intcon(round_mask); 3543 header_size = _gvn.transform( new(C) AddINode(hsize, mask) ); 3544 } 3545 3546 Node* elem_shift = NULL; 3547 if (layout_is_con) { 3548 int eshift = Klass::layout_helper_log2_element_size(layout_con); 3549 if (eshift != 0) 3550 elem_shift = intcon(eshift); 3551 } else { 3552 // There is no need to mask or shift this value. 3553 // The semantics of LShiftINode include an implicit mask to 0x1F. 3554 assert(Klass::_lh_log2_element_size_shift == 0, "use shift in place"); 3555 elem_shift = layout_val; 3556 } 3557 3558 // Transition to native address size for all offset calculations: 3559 Node* lengthx = ConvI2X(length); 3560 Node* headerx = ConvI2X(header_size); 3561 #ifdef _LP64 3562 { const TypeInt* tilen = _gvn.find_int_type(length); 3563 if (tilen != NULL && tilen->_lo < 0) { 3564 // Add a manual constraint to a positive range. Cf. array_element_address. 3565 jlong size_max = fast_size_limit; 3566 if (size_max > tilen->_hi) size_max = tilen->_hi; 3567 const TypeInt* tlcon = TypeInt::make(0, size_max, Type::WidenMin); 3568 3569 // Only do a narrow I2L conversion if the range check passed. 3570 IfNode* iff = new (C) IfNode(control(), initial_slow_test, PROB_MIN, COUNT_UNKNOWN); 3571 _gvn.transform(iff); 3572 RegionNode* region = new (C) RegionNode(3); 3573 _gvn.set_type(region, Type::CONTROL); 3574 lengthx = new (C) PhiNode(region, TypeLong::LONG); 3575 _gvn.set_type(lengthx, TypeLong::LONG); 3576 3577 // Range check passed. Use ConvI2L node with narrow type. 3578 Node* passed = IfFalse(iff); 3579 region->init_req(1, passed); 3580 // Make I2L conversion control dependent to prevent it from 3581 // floating above the range check during loop optimizations. 3582 lengthx->init_req(1, C->constrained_convI2L(&_gvn, length, tlcon, passed)); 3583 3584 // Range check failed. Use ConvI2L with wide type because length may be invalid. 3585 region->init_req(2, IfTrue(iff)); 3586 lengthx->init_req(2, ConvI2X(length)); 3587 3588 set_control(region); 3589 record_for_igvn(region); 3590 record_for_igvn(lengthx); 3591 } 3592 } 3593 #endif 3594 3595 // Combine header size (plus rounding) and body size. Then round down. 3596 // This computation cannot overflow, because it is used only in two 3597 // places, one where the length is sharply limited, and the other 3598 // after a successful allocation. 3599 Node* abody = lengthx; 3600 if (elem_shift != NULL) 3601 abody = _gvn.transform( new(C) LShiftXNode(lengthx, elem_shift) ); 3602 Node* size = _gvn.transform( new(C) AddXNode(headerx, abody) ); 3603 if (round_mask != 0) { 3604 Node* mask = MakeConX(~round_mask); 3605 size = _gvn.transform( new(C) AndXNode(size, mask) ); 3606 } 3607 // else if round_mask == 0, the size computation is self-rounding 3608 3609 if (return_size_val != NULL) { 3610 // This is the size 3611 (*return_size_val) = size; 3612 } 3613 3614 // Now generate allocation code 3615 3616 // The entire memory state is needed for slow path of the allocation 3617 // since GC and deoptimization can happened. 3618 Node *mem = reset_memory(); 3619 set_all_memory(mem); // Create new memory state 3620 3621 if (initial_slow_test->is_Bool()) { 3622 // Hide it behind a CMoveI, or else PhaseIdealLoop::split_up will get sick. 3623 initial_slow_test = initial_slow_test->as_Bool()->as_int_value(&_gvn); 3624 } 3625 3626 // Create the AllocateArrayNode and its result projections 3627 AllocateArrayNode* alloc 3628 = new (C) AllocateArrayNode(C, AllocateArrayNode::alloc_type(TypeInt::INT), 3629 control(), mem, i_o(), 3630 size, klass_node, 3631 initial_slow_test, 3632 length); 3633 3634 // Cast to correct type. Note that the klass_node may be constant or not, 3635 // and in the latter case the actual array type will be inexact also. 3636 // (This happens via a non-constant argument to inline_native_newArray.) 3637 // In any case, the value of klass_node provides the desired array type. 3638 const TypeInt* length_type = _gvn.find_int_type(length); 3639 const TypeOopPtr* ary_type = _gvn.type(klass_node)->is_klassptr()->as_instance_type(); 3640 if (ary_type->isa_aryptr() && length_type != NULL) { 3641 // Try to get a better type than POS for the size 3642 ary_type = ary_type->is_aryptr()->cast_to_size(length_type); 3643 } 3644 3645 Node* javaoop = set_output_for_allocation(alloc, ary_type, deoptimize_on_exception); 3646 3647 // Cast length on remaining path to be as narrow as possible 3648 if (map()->find_edge(length) >= 0) { 3649 Node* ccast = alloc->make_ideal_length(ary_type, &_gvn); 3650 if (ccast != length) { 3651 _gvn.set_type_bottom(ccast); 3652 record_for_igvn(ccast); 3653 replace_in_map(length, ccast); 3654 } 3655 } 3656 3657 return javaoop; 3658 } 3659 3660 // The following "Ideal_foo" functions are placed here because they recognize 3661 // the graph shapes created by the functions immediately above. 3662 3663 //---------------------------Ideal_allocation---------------------------------- 3664 // Given an oop pointer or raw pointer, see if it feeds from an AllocateNode. 3665 AllocateNode* AllocateNode::Ideal_allocation(Node* ptr, PhaseTransform* phase) { 3666 if (ptr == NULL) { // reduce dumb test in callers 3667 return NULL; 3668 } 3669 if (ptr->is_CheckCastPP()) { // strip only one raw-to-oop cast 3670 ptr = ptr->in(1); 3671 if (ptr == NULL) return NULL; 3672 } 3673 // Return NULL for allocations with several casts: 3674 // j.l.reflect.Array.newInstance(jobject, jint) 3675 // Object.clone() 3676 // to keep more precise type from last cast. 3677 if (ptr->is_Proj()) { 3678 Node* allo = ptr->in(0); 3679 if (allo != NULL && allo->is_Allocate()) { 3680 return allo->as_Allocate(); 3681 } 3682 } 3683 // Report failure to match. 3684 return NULL; 3685 } 3686 3687 // Fancy version which also strips off an offset (and reports it to caller). 3688 AllocateNode* AllocateNode::Ideal_allocation(Node* ptr, PhaseTransform* phase, 3689 intptr_t& offset) { 3690 Node* base = AddPNode::Ideal_base_and_offset(ptr, phase, offset); 3691 if (base == NULL) return NULL; 3692 return Ideal_allocation(base, phase); 3693 } 3694 3695 // Trace Initialize <- Proj[Parm] <- Allocate 3696 AllocateNode* InitializeNode::allocation() { 3697 Node* rawoop = in(InitializeNode::RawAddress); 3698 if (rawoop->is_Proj()) { 3699 Node* alloc = rawoop->in(0); 3700 if (alloc->is_Allocate()) { 3701 return alloc->as_Allocate(); 3702 } 3703 } 3704 return NULL; 3705 } 3706 3707 // Trace Allocate -> Proj[Parm] -> Initialize 3708 InitializeNode* AllocateNode::initialization() { 3709 ProjNode* rawoop = proj_out(AllocateNode::RawAddress); 3710 if (rawoop == NULL) return NULL; 3711 for (DUIterator_Fast imax, i = rawoop->fast_outs(imax); i < imax; i++) { 3712 Node* init = rawoop->fast_out(i); 3713 if (init->is_Initialize()) { 3714 assert(init->as_Initialize()->allocation() == this, "2-way link"); 3715 return init->as_Initialize(); 3716 } 3717 } 3718 return NULL; 3719 } 3720 3721 //----------------------------- loop predicates --------------------------- 3722 3723 //------------------------------add_predicate_impl---------------------------- 3724 void GraphKit::add_predicate_impl(Deoptimization::DeoptReason reason, int nargs) { 3725 // Too many traps seen? 3726 if (too_many_traps(reason)) { 3727 #ifdef ASSERT 3728 if (TraceLoopPredicate) { 3729 int tc = C->trap_count(reason); 3730 tty->print("too many traps=%s tcount=%d in ", 3731 Deoptimization::trap_reason_name(reason), tc); 3732 method()->print(); // which method has too many predicate traps 3733 tty->cr(); 3734 } 3735 #endif 3736 // We cannot afford to take more traps here, 3737 // do not generate predicate. 3738 return; 3739 } 3740 3741 Node *cont = _gvn.intcon(1); 3742 Node* opq = _gvn.transform(new (C) Opaque1Node(C, cont)); 3743 Node *bol = _gvn.transform(new (C) Conv2BNode(opq)); 3744 IfNode* iff = create_and_map_if(control(), bol, PROB_MAX, COUNT_UNKNOWN); 3745 Node* iffalse = _gvn.transform(new (C) IfFalseNode(iff)); 3746 C->add_predicate_opaq(opq); 3747 { 3748 PreserveJVMState pjvms(this); 3749 set_control(iffalse); 3750 inc_sp(nargs); 3751 uncommon_trap(reason, Deoptimization::Action_maybe_recompile); 3752 } 3753 Node* iftrue = _gvn.transform(new (C) IfTrueNode(iff)); 3754 set_control(iftrue); 3755 } 3756 3757 //------------------------------add_predicate--------------------------------- 3758 void GraphKit::add_predicate(int nargs) { 3759 if (UseLoopPredicate) { 3760 add_predicate_impl(Deoptimization::Reason_predicate, nargs); 3761 } 3762 // loop's limit check predicate should be near the loop. 3763 if (LoopLimitCheck) { 3764 add_predicate_impl(Deoptimization::Reason_loop_limit_check, nargs); 3765 } 3766 } 3767 3768 //----------------------------- store barriers ---------------------------- 3769 #define __ ideal. 3770 3771 void GraphKit::sync_kit(IdealKit& ideal) { 3772 set_all_memory(__ merged_memory()); 3773 set_i_o(__ i_o()); 3774 set_control(__ ctrl()); 3775 } 3776 3777 void GraphKit::final_sync(IdealKit& ideal) { 3778 // Final sync IdealKit and graphKit. 3779 sync_kit(ideal); 3780 } 3781 3782 // vanilla/CMS post barrier 3783 // Insert a write-barrier store. This is to let generational GC work; we have 3784 // to flag all oop-stores before the next GC point. 3785 void GraphKit::write_barrier_post(Node* oop_store, 3786 Node* obj, 3787 Node* adr, 3788 uint adr_idx, 3789 Node* val, 3790 bool use_precise) { 3791 // No store check needed if we're storing a NULL or an old object 3792 // (latter case is probably a string constant). The concurrent 3793 // mark sweep garbage collector, however, needs to have all nonNull 3794 // oop updates flagged via card-marks. 3795 if (val != NULL && val->is_Con()) { 3796 // must be either an oop or NULL 3797 const Type* t = val->bottom_type(); 3798 if (t == TypePtr::NULL_PTR || t == Type::TOP) 3799 // stores of null never (?) need barriers 3800 return; 3801 } 3802 3803 if (use_ReduceInitialCardMarks() 3804 && obj == just_allocated_object(control())) { 3805 // We can skip marks on a freshly-allocated object in Eden. 3806 // Keep this code in sync with new_store_pre_barrier() in runtime.cpp. 3807 // That routine informs GC to take appropriate compensating steps, 3808 // upon a slow-path allocation, so as to make this card-mark 3809 // elision safe. 3810 return; 3811 } 3812 3813 if (!use_precise) { 3814 // All card marks for a (non-array) instance are in one place: 3815 adr = obj; 3816 } 3817 // (Else it's an array (or unknown), and we want more precise card marks.) 3818 assert(adr != NULL, ""); 3819 3820 IdealKit ideal(this, true); 3821 3822 // Convert the pointer to an int prior to doing math on it 3823 Node* cast = __ CastPX(__ ctrl(), adr); 3824 3825 // Divide by card size 3826 assert(Universe::heap()->barrier_set()->kind() == BarrierSet::CardTableModRef, 3827 "Only one we handle so far."); 3828 Node* card_offset = __ URShiftX( cast, __ ConI(CardTableModRefBS::card_shift) ); 3829 3830 // Combine card table base and card offset 3831 Node* card_adr = __ AddP(__ top(), byte_map_base_node(), card_offset ); 3832 3833 // Get the alias_index for raw card-mark memory 3834 int adr_type = Compile::AliasIdxRaw; 3835 Node* zero = __ ConI(0); // Dirty card value 3836 BasicType bt = T_BYTE; 3837 3838 if (UseCondCardMark) { 3839 // The classic GC reference write barrier is typically implemented 3840 // as a store into the global card mark table. Unfortunately 3841 // unconditional stores can result in false sharing and excessive 3842 // coherence traffic as well as false transactional aborts. 3843 // UseCondCardMark enables MP "polite" conditional card mark 3844 // stores. In theory we could relax the load from ctrl() to 3845 // no_ctrl, but that doesn't buy much latitude. 3846 Node* card_val = __ load( __ ctrl(), card_adr, TypeInt::BYTE, bt, adr_type); 3847 __ if_then(card_val, BoolTest::ne, zero); 3848 } 3849 3850 // Smash zero into card 3851 if( !UseConcMarkSweepGC ) { 3852 __ store(__ ctrl(), card_adr, zero, bt, adr_type, MemNode::release); 3853 } else { 3854 // Specialized path for CM store barrier 3855 __ storeCM(__ ctrl(), card_adr, zero, oop_store, adr_idx, bt, adr_type); 3856 } 3857 3858 if (UseCondCardMark) { 3859 __ end_if(); 3860 } 3861 3862 // Final sync IdealKit and GraphKit. 3863 final_sync(ideal); 3864 } 3865 3866 // G1 pre/post barriers 3867 void GraphKit::g1_write_barrier_pre(bool do_load, 3868 Node* obj, 3869 Node* adr, 3870 uint alias_idx, 3871 Node* val, 3872 const TypeOopPtr* val_type, 3873 Node* pre_val, 3874 BasicType bt) { 3875 3876 // Some sanity checks 3877 // Note: val is unused in this routine. 3878 3879 if (do_load) { 3880 // We need to generate the load of the previous value 3881 assert(obj != NULL, "must have a base"); 3882 assert(adr != NULL, "where are loading from?"); 3883 assert(pre_val == NULL, "loaded already?"); 3884 assert(val_type != NULL, "need a type"); 3885 } else { 3886 // In this case both val_type and alias_idx are unused. 3887 assert(pre_val != NULL, "must be loaded already"); 3888 // Nothing to be done if pre_val is null. 3889 if (pre_val->bottom_type() == TypePtr::NULL_PTR) return; 3890 assert(pre_val->bottom_type()->basic_type() == T_OBJECT, "or we shouldn't be here"); 3891 } 3892 assert(bt == T_OBJECT, "or we shouldn't be here"); 3893 3894 IdealKit ideal(this, true); 3895 3896 Node* tls = __ thread(); // ThreadLocalStorage 3897 3898 Node* no_ctrl = NULL; 3899 Node* no_base = __ top(); 3900 Node* zero = __ ConI(0); 3901 Node* zeroX = __ ConX(0); 3902 3903 float likely = PROB_LIKELY(0.999); 3904 float unlikely = PROB_UNLIKELY(0.999); 3905 3906 BasicType active_type = in_bytes(PtrQueue::byte_width_of_active()) == 4 ? T_INT : T_BYTE; 3907 assert(in_bytes(PtrQueue::byte_width_of_active()) == 4 || in_bytes(PtrQueue::byte_width_of_active()) == 1, "flag width"); 3908 3909 // Offsets into the thread 3910 const int marking_offset = in_bytes(JavaThread::satb_mark_queue_offset() + // 648 3911 PtrQueue::byte_offset_of_active()); 3912 const int index_offset = in_bytes(JavaThread::satb_mark_queue_offset() + // 656 3913 PtrQueue::byte_offset_of_index()); 3914 const int buffer_offset = in_bytes(JavaThread::satb_mark_queue_offset() + // 652 3915 PtrQueue::byte_offset_of_buf()); 3916 3917 // Now the actual pointers into the thread 3918 Node* marking_adr = __ AddP(no_base, tls, __ ConX(marking_offset)); 3919 Node* buffer_adr = __ AddP(no_base, tls, __ ConX(buffer_offset)); 3920 Node* index_adr = __ AddP(no_base, tls, __ ConX(index_offset)); 3921 3922 // Now some of the values 3923 Node* marking = __ load(__ ctrl(), marking_adr, TypeInt::INT, active_type, Compile::AliasIdxRaw); 3924 3925 // if (!marking) 3926 __ if_then(marking, BoolTest::ne, zero, unlikely); { 3927 BasicType index_bt = TypeX_X->basic_type(); 3928 assert(sizeof(size_t) == type2aelembytes(index_bt), "Loading G1 PtrQueue::_index with wrong size."); 3929 Node* index = __ load(__ ctrl(), index_adr, TypeX_X, index_bt, Compile::AliasIdxRaw); 3930 3931 if (do_load) { 3932 // load original value 3933 // alias_idx correct?? 3934 pre_val = __ load(__ ctrl(), adr, val_type, bt, alias_idx); 3935 } 3936 3937 // if (pre_val != NULL) 3938 __ if_then(pre_val, BoolTest::ne, null()); { 3939 Node* buffer = __ load(__ ctrl(), buffer_adr, TypeRawPtr::NOTNULL, T_ADDRESS, Compile::AliasIdxRaw); 3940 3941 // is the queue for this thread full? 3942 __ if_then(index, BoolTest::ne, zeroX, likely); { 3943 3944 // decrement the index 3945 Node* next_index = _gvn.transform(new (C) SubXNode(index, __ ConX(sizeof(intptr_t)))); 3946 3947 // Now get the buffer location we will log the previous value into and store it 3948 Node *log_addr = __ AddP(no_base, buffer, next_index); 3949 __ store(__ ctrl(), log_addr, pre_val, T_OBJECT, Compile::AliasIdxRaw, MemNode::unordered); 3950 // update the index 3951 __ store(__ ctrl(), index_adr, next_index, index_bt, Compile::AliasIdxRaw, MemNode::unordered); 3952 3953 } __ else_(); { 3954 3955 // logging buffer is full, call the runtime 3956 const TypeFunc *tf = OptoRuntime::g1_wb_pre_Type(); 3957 __ make_leaf_call(tf, CAST_FROM_FN_PTR(address, SharedRuntime::g1_wb_pre), "g1_wb_pre", pre_val, tls); 3958 } __ end_if(); // (!index) 3959 } __ end_if(); // (pre_val != NULL) 3960 } __ end_if(); // (!marking) 3961 3962 // Final sync IdealKit and GraphKit. 3963 final_sync(ideal); 3964 } 3965 3966 // 3967 // Update the card table and add card address to the queue 3968 // 3969 void GraphKit::g1_mark_card(IdealKit& ideal, 3970 Node* card_adr, 3971 Node* oop_store, 3972 uint oop_alias_idx, 3973 Node* index, 3974 Node* index_adr, 3975 Node* buffer, 3976 const TypeFunc* tf) { 3977 3978 Node* zero = __ ConI(0); 3979 Node* zeroX = __ ConX(0); 3980 Node* no_base = __ top(); 3981 BasicType card_bt = T_BYTE; 3982 // Smash zero into card. MUST BE ORDERED WRT TO STORE 3983 __ storeCM(__ ctrl(), card_adr, zero, oop_store, oop_alias_idx, card_bt, Compile::AliasIdxRaw); 3984 3985 // Now do the queue work 3986 __ if_then(index, BoolTest::ne, zeroX); { 3987 3988 Node* next_index = _gvn.transform(new (C) SubXNode(index, __ ConX(sizeof(intptr_t)))); 3989 Node* log_addr = __ AddP(no_base, buffer, next_index); 3990 3991 // Order, see storeCM. 3992 __ store(__ ctrl(), log_addr, card_adr, T_ADDRESS, Compile::AliasIdxRaw, MemNode::unordered); 3993 __ store(__ ctrl(), index_adr, next_index, TypeX_X->basic_type(), Compile::AliasIdxRaw, MemNode::unordered); 3994 3995 } __ else_(); { 3996 __ make_leaf_call(tf, CAST_FROM_FN_PTR(address, SharedRuntime::g1_wb_post), "g1_wb_post", card_adr, __ thread()); 3997 } __ end_if(); 3998 3999 } 4000 4001 void GraphKit::g1_write_barrier_post(Node* oop_store, 4002 Node* obj, 4003 Node* adr, 4004 uint alias_idx, 4005 Node* val, 4006 BasicType bt, 4007 bool use_precise) { 4008 // If we are writing a NULL then we need no post barrier 4009 4010 if (val != NULL && val->is_Con() && val->bottom_type() == TypePtr::NULL_PTR) { 4011 // Must be NULL 4012 const Type* t = val->bottom_type(); 4013 assert(t == Type::TOP || t == TypePtr::NULL_PTR, "must be NULL"); 4014 // No post barrier if writing NULLx 4015 return; 4016 } 4017 4018 if (!use_precise) { 4019 // All card marks for a (non-array) instance are in one place: 4020 adr = obj; 4021 } 4022 // (Else it's an array (or unknown), and we want more precise card marks.) 4023 assert(adr != NULL, ""); 4024 4025 IdealKit ideal(this, true); 4026 4027 Node* tls = __ thread(); // ThreadLocalStorage 4028 4029 Node* no_base = __ top(); 4030 float likely = PROB_LIKELY(0.999); 4031 float unlikely = PROB_UNLIKELY(0.999); 4032 Node* young_card = __ ConI((jint)G1SATBCardTableModRefBS::g1_young_card_val()); 4033 Node* dirty_card = __ ConI((jint)CardTableModRefBS::dirty_card_val()); 4034 Node* zeroX = __ ConX(0); 4035 4036 // Get the alias_index for raw card-mark memory 4037 const TypePtr* card_type = TypeRawPtr::BOTTOM; 4038 4039 const TypeFunc *tf = OptoRuntime::g1_wb_post_Type(); 4040 4041 // Offsets into the thread 4042 const int index_offset = in_bytes(JavaThread::dirty_card_queue_offset() + 4043 PtrQueue::byte_offset_of_index()); 4044 const int buffer_offset = in_bytes(JavaThread::dirty_card_queue_offset() + 4045 PtrQueue::byte_offset_of_buf()); 4046 4047 // Pointers into the thread 4048 4049 Node* buffer_adr = __ AddP(no_base, tls, __ ConX(buffer_offset)); 4050 Node* index_adr = __ AddP(no_base, tls, __ ConX(index_offset)); 4051 4052 // Now some values 4053 // Use ctrl to avoid hoisting these values past a safepoint, which could 4054 // potentially reset these fields in the JavaThread. 4055 Node* index = __ load(__ ctrl(), index_adr, TypeX_X, TypeX_X->basic_type(), Compile::AliasIdxRaw); 4056 Node* buffer = __ load(__ ctrl(), buffer_adr, TypeRawPtr::NOTNULL, T_ADDRESS, Compile::AliasIdxRaw); 4057 4058 // Convert the store obj pointer to an int prior to doing math on it 4059 // Must use ctrl to prevent "integerized oop" existing across safepoint 4060 Node* cast = __ CastPX(__ ctrl(), adr); 4061 4062 // Divide pointer by card size 4063 Node* card_offset = __ URShiftX( cast, __ ConI(CardTableModRefBS::card_shift) ); 4064 4065 // Combine card table base and card offset 4066 Node* card_adr = __ AddP(no_base, byte_map_base_node(), card_offset ); 4067 4068 // If we know the value being stored does it cross regions? 4069 4070 if (val != NULL) { 4071 // Does the store cause us to cross regions? 4072 4073 // Should be able to do an unsigned compare of region_size instead of 4074 // and extra shift. Do we have an unsigned compare?? 4075 // Node* region_size = __ ConI(1 << HeapRegion::LogOfHRGrainBytes); 4076 Node* xor_res = __ URShiftX ( __ XorX( cast, __ CastPX(__ ctrl(), val)), __ ConI(HeapRegion::LogOfHRGrainBytes)); 4077 4078 // if (xor_res == 0) same region so skip 4079 __ if_then(xor_res, BoolTest::ne, zeroX); { 4080 4081 // No barrier if we are storing a NULL 4082 __ if_then(val, BoolTest::ne, null(), unlikely); { 4083 4084 // Ok must mark the card if not already dirty 4085 4086 // load the original value of the card 4087 Node* card_val = __ load(__ ctrl(), card_adr, TypeInt::INT, T_BYTE, Compile::AliasIdxRaw); 4088 4089 __ if_then(card_val, BoolTest::ne, young_card); { 4090 sync_kit(ideal); 4091 // Use Op_MemBarVolatile to achieve the effect of a StoreLoad barrier. 4092 insert_mem_bar(Op_MemBarVolatile, oop_store); 4093 __ sync_kit(this); 4094 4095 Node* card_val_reload = __ load(__ ctrl(), card_adr, TypeInt::INT, T_BYTE, Compile::AliasIdxRaw); 4096 __ if_then(card_val_reload, BoolTest::ne, dirty_card); { 4097 g1_mark_card(ideal, card_adr, oop_store, alias_idx, index, index_adr, buffer, tf); 4098 } __ end_if(); 4099 } __ end_if(); 4100 } __ end_if(); 4101 } __ end_if(); 4102 } else { 4103 // Object.clone() instrinsic uses this path. 4104 g1_mark_card(ideal, card_adr, oop_store, alias_idx, index, index_adr, buffer, tf); 4105 } 4106 4107 // Final sync IdealKit and GraphKit. 4108 final_sync(ideal); 4109 } 4110 #undef __ 4111 4112 4113 4114 Node* GraphKit::load_String_offset(Node* ctrl, Node* str) { 4115 if (java_lang_String::has_offset_field()) { 4116 int offset_offset = java_lang_String::offset_offset_in_bytes(); 4117 const TypeInstPtr* string_type = TypeInstPtr::make(TypePtr::NotNull, C->env()->String_klass(), 4118 false, NULL, 0); 4119 const TypePtr* offset_field_type = string_type->add_offset(offset_offset); 4120 int offset_field_idx = C->get_alias_index(offset_field_type); 4121 return make_load(ctrl, 4122 basic_plus_adr(str, str, offset_offset), 4123 TypeInt::INT, T_INT, offset_field_idx, MemNode::unordered); 4124 } else { 4125 return intcon(0); 4126 } 4127 } 4128 4129 Node* GraphKit::load_String_length(Node* ctrl, Node* str) { 4130 if (java_lang_String::has_count_field()) { 4131 int count_offset = java_lang_String::count_offset_in_bytes(); 4132 const TypeInstPtr* string_type = TypeInstPtr::make(TypePtr::NotNull, C->env()->String_klass(), 4133 false, NULL, 0); 4134 const TypePtr* count_field_type = string_type->add_offset(count_offset); 4135 int count_field_idx = C->get_alias_index(count_field_type); 4136 return make_load(ctrl, 4137 basic_plus_adr(str, str, count_offset), 4138 TypeInt::INT, T_INT, count_field_idx, MemNode::unordered); 4139 } else { 4140 return load_array_length(load_String_value(ctrl, str)); 4141 } 4142 } 4143 4144 Node* GraphKit::load_String_value(Node* ctrl, Node* str) { 4145 int value_offset = java_lang_String::value_offset_in_bytes(); 4146 const TypeInstPtr* string_type = TypeInstPtr::make(TypePtr::NotNull, C->env()->String_klass(), 4147 false, NULL, 0); 4148 const TypePtr* value_field_type = string_type->add_offset(value_offset); 4149 const TypeAryPtr* value_type = TypeAryPtr::make(TypePtr::NotNull, 4150 TypeAry::make(TypeInt::CHAR,TypeInt::POS), 4151 ciTypeArrayKlass::make(T_CHAR), true, 0); 4152 int value_field_idx = C->get_alias_index(value_field_type); 4153 Node* load = make_load(ctrl, basic_plus_adr(str, str, value_offset), 4154 value_type, T_OBJECT, value_field_idx, MemNode::unordered); 4155 // String.value field is known to be @Stable. 4156 if (UseImplicitStableValues) { 4157 load = cast_array_to_stable(load, value_type); 4158 } 4159 return load; 4160 } 4161 4162 void GraphKit::store_String_offset(Node* ctrl, Node* str, Node* value) { 4163 int offset_offset = java_lang_String::offset_offset_in_bytes(); 4164 const TypeInstPtr* string_type = TypeInstPtr::make(TypePtr::NotNull, C->env()->String_klass(), 4165 false, NULL, 0); 4166 const TypePtr* offset_field_type = string_type->add_offset(offset_offset); 4167 int offset_field_idx = C->get_alias_index(offset_field_type); 4168 store_to_memory(ctrl, basic_plus_adr(str, offset_offset), 4169 value, T_INT, offset_field_idx, MemNode::unordered); 4170 } 4171 4172 void GraphKit::store_String_value(Node* ctrl, Node* str, Node* value) { 4173 int value_offset = java_lang_String::value_offset_in_bytes(); 4174 const TypeInstPtr* string_type = TypeInstPtr::make(TypePtr::NotNull, C->env()->String_klass(), 4175 false, NULL, 0); 4176 const TypePtr* value_field_type = string_type->add_offset(value_offset); 4177 4178 store_oop_to_object(ctrl, str, basic_plus_adr(str, value_offset), value_field_type, 4179 value, TypeAryPtr::CHARS, T_OBJECT, MemNode::unordered); 4180 } 4181 4182 void GraphKit::store_String_length(Node* ctrl, Node* str, Node* value) { 4183 int count_offset = java_lang_String::count_offset_in_bytes(); 4184 const TypeInstPtr* string_type = TypeInstPtr::make(TypePtr::NotNull, C->env()->String_klass(), 4185 false, NULL, 0); 4186 const TypePtr* count_field_type = string_type->add_offset(count_offset); 4187 int count_field_idx = C->get_alias_index(count_field_type); 4188 store_to_memory(ctrl, basic_plus_adr(str, count_offset), 4189 value, T_INT, count_field_idx, MemNode::unordered); 4190 } 4191 4192 Node* GraphKit::cast_array_to_stable(Node* ary, const TypeAryPtr* ary_type) { 4193 // Reify the property as a CastPP node in Ideal graph to comply with monotonicity 4194 // assumption of CCP analysis. 4195 return _gvn.transform(new(C) CastPPNode(ary, ary_type->cast_to_stable(true))); 4196 }