1 /* 2 * Copyright (c) 2001, 2018, 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 "ci/ciUtilities.hpp" 27 #include "compiler/compileLog.hpp" 28 #include "gc/shared/barrierSet.hpp" 29 #include "gc/shared/c2/barrierSetC2.hpp" 30 #include "interpreter/interpreter.hpp" 31 #include "memory/resourceArea.hpp" 32 #include "opto/addnode.hpp" 33 #include "opto/castnode.hpp" 34 #include "opto/convertnode.hpp" 35 #include "opto/graphKit.hpp" 36 #include "opto/idealKit.hpp" 37 #include "opto/intrinsicnode.hpp" 38 #include "opto/locknode.hpp" 39 #include "opto/machnode.hpp" 40 #include "opto/opaquenode.hpp" 41 #include "opto/parse.hpp" 42 #include "opto/rootnode.hpp" 43 #include "opto/runtime.hpp" 44 #include "runtime/deoptimization.hpp" 45 #include "runtime/sharedRuntime.hpp" 46 47 //----------------------------GraphKit----------------------------------------- 48 // Main utility constructor. 49 GraphKit::GraphKit(JVMState* jvms) 50 : Phase(Phase::Parser), 51 _env(C->env()), 52 _gvn(*C->initial_gvn()), 53 _barrier_set(BarrierSet::barrier_set()->barrier_set_c2()) 54 { 55 _exceptions = jvms->map()->next_exception(); 56 if (_exceptions != NULL) jvms->map()->set_next_exception(NULL); 57 set_jvms(jvms); 58 } 59 60 // Private constructor for parser. 61 GraphKit::GraphKit() 62 : Phase(Phase::Parser), 63 _env(C->env()), 64 _gvn(*C->initial_gvn()), 65 _barrier_set(BarrierSet::barrier_set()->barrier_set_c2()) 66 { 67 _exceptions = NULL; 68 set_map(NULL); 69 debug_only(_sp = -99); 70 debug_only(set_bci(-99)); 71 } 72 73 74 75 //---------------------------clean_stack--------------------------------------- 76 // Clear away rubbish from the stack area of the JVM state. 77 // This destroys any arguments that may be waiting on the stack. 78 void GraphKit::clean_stack(int from_sp) { 79 SafePointNode* map = this->map(); 80 JVMState* jvms = this->jvms(); 81 int stk_size = jvms->stk_size(); 82 int stkoff = jvms->stkoff(); 83 Node* top = this->top(); 84 for (int i = from_sp; i < stk_size; i++) { 85 if (map->in(stkoff + i) != top) { 86 map->set_req(stkoff + i, top); 87 } 88 } 89 } 90 91 92 //--------------------------------sync_jvms----------------------------------- 93 // Make sure our current jvms agrees with our parse state. 94 JVMState* GraphKit::sync_jvms() const { 95 JVMState* jvms = this->jvms(); 96 jvms->set_bci(bci()); // Record the new bci in the JVMState 97 jvms->set_sp(sp()); // Record the new sp in the JVMState 98 assert(jvms_in_sync(), "jvms is now in sync"); 99 return jvms; 100 } 101 102 //--------------------------------sync_jvms_for_reexecute--------------------- 103 // Make sure our current jvms agrees with our parse state. This version 104 // uses the reexecute_sp for reexecuting bytecodes. 105 JVMState* GraphKit::sync_jvms_for_reexecute() { 106 JVMState* jvms = this->jvms(); 107 jvms->set_bci(bci()); // Record the new bci in the JVMState 108 jvms->set_sp(reexecute_sp()); // Record the new sp in the JVMState 109 return jvms; 110 } 111 112 #ifdef ASSERT 113 bool GraphKit::jvms_in_sync() const { 114 Parse* parse = is_Parse(); 115 if (parse == NULL) { 116 if (bci() != jvms()->bci()) return false; 117 if (sp() != (int)jvms()->sp()) return false; 118 return true; 119 } 120 if (jvms()->method() != parse->method()) return false; 121 if (jvms()->bci() != parse->bci()) return false; 122 int jvms_sp = jvms()->sp(); 123 if (jvms_sp != parse->sp()) return false; 124 int jvms_depth = jvms()->depth(); 125 if (jvms_depth != parse->depth()) return false; 126 return true; 127 } 128 129 // Local helper checks for special internal merge points 130 // used to accumulate and merge exception states. 131 // They are marked by the region's in(0) edge being the map itself. 132 // Such merge points must never "escape" into the parser at large, 133 // until they have been handed to gvn.transform. 134 static bool is_hidden_merge(Node* reg) { 135 if (reg == NULL) return false; 136 if (reg->is_Phi()) { 137 reg = reg->in(0); 138 if (reg == NULL) return false; 139 } 140 return reg->is_Region() && reg->in(0) != NULL && reg->in(0)->is_Root(); 141 } 142 143 void GraphKit::verify_map() const { 144 if (map() == NULL) return; // null map is OK 145 assert(map()->req() <= jvms()->endoff(), "no extra garbage on map"); 146 assert(!map()->has_exceptions(), "call add_exception_states_from 1st"); 147 assert(!is_hidden_merge(control()), "call use_exception_state, not set_map"); 148 } 149 150 void GraphKit::verify_exception_state(SafePointNode* ex_map) { 151 assert(ex_map->next_exception() == NULL, "not already part of a chain"); 152 assert(has_saved_ex_oop(ex_map), "every exception state has an ex_oop"); 153 } 154 #endif 155 156 //---------------------------stop_and_kill_map--------------------------------- 157 // Set _map to NULL, signalling a stop to further bytecode execution. 158 // First smash the current map's control to a constant, to mark it dead. 159 void GraphKit::stop_and_kill_map() { 160 SafePointNode* dead_map = stop(); 161 if (dead_map != NULL) { 162 dead_map->disconnect_inputs(NULL, C); // Mark the map as killed. 163 assert(dead_map->is_killed(), "must be so marked"); 164 } 165 } 166 167 168 //--------------------------------stopped-------------------------------------- 169 // Tell if _map is NULL, or control is top. 170 bool GraphKit::stopped() { 171 if (map() == NULL) return true; 172 else if (control() == top()) return true; 173 else return false; 174 } 175 176 177 //-----------------------------has_ex_handler---------------------------------- 178 // Tell if this method or any caller method has exception handlers. 179 bool GraphKit::has_ex_handler() { 180 for (JVMState* jvmsp = jvms(); jvmsp != NULL; jvmsp = jvmsp->caller()) { 181 if (jvmsp->has_method() && jvmsp->method()->has_exception_handlers()) { 182 return true; 183 } 184 } 185 return false; 186 } 187 188 //------------------------------save_ex_oop------------------------------------ 189 // Save an exception without blowing stack contents or other JVM state. 190 void GraphKit::set_saved_ex_oop(SafePointNode* ex_map, Node* ex_oop) { 191 assert(!has_saved_ex_oop(ex_map), "clear ex-oop before setting again"); 192 ex_map->add_req(ex_oop); 193 debug_only(verify_exception_state(ex_map)); 194 } 195 196 inline static Node* common_saved_ex_oop(SafePointNode* ex_map, bool clear_it) { 197 assert(GraphKit::has_saved_ex_oop(ex_map), "ex_oop must be there"); 198 Node* ex_oop = ex_map->in(ex_map->req()-1); 199 if (clear_it) ex_map->del_req(ex_map->req()-1); 200 return ex_oop; 201 } 202 203 //-----------------------------saved_ex_oop------------------------------------ 204 // Recover a saved exception from its map. 205 Node* GraphKit::saved_ex_oop(SafePointNode* ex_map) { 206 return common_saved_ex_oop(ex_map, false); 207 } 208 209 //--------------------------clear_saved_ex_oop--------------------------------- 210 // Erase a previously saved exception from its map. 211 Node* GraphKit::clear_saved_ex_oop(SafePointNode* ex_map) { 212 return common_saved_ex_oop(ex_map, true); 213 } 214 215 #ifdef ASSERT 216 //---------------------------has_saved_ex_oop---------------------------------- 217 // Erase a previously saved exception from its map. 218 bool GraphKit::has_saved_ex_oop(SafePointNode* ex_map) { 219 return ex_map->req() == ex_map->jvms()->endoff()+1; 220 } 221 #endif 222 223 //-------------------------make_exception_state-------------------------------- 224 // Turn the current JVM state into an exception state, appending the ex_oop. 225 SafePointNode* GraphKit::make_exception_state(Node* ex_oop) { 226 sync_jvms(); 227 SafePointNode* ex_map = stop(); // do not manipulate this map any more 228 set_saved_ex_oop(ex_map, ex_oop); 229 return ex_map; 230 } 231 232 233 //--------------------------add_exception_state-------------------------------- 234 // Add an exception to my list of exceptions. 235 void GraphKit::add_exception_state(SafePointNode* ex_map) { 236 if (ex_map == NULL || ex_map->control() == top()) { 237 return; 238 } 239 #ifdef ASSERT 240 verify_exception_state(ex_map); 241 if (has_exceptions()) { 242 assert(ex_map->jvms()->same_calls_as(_exceptions->jvms()), "all collected exceptions must come from the same place"); 243 } 244 #endif 245 246 // If there is already an exception of exactly this type, merge with it. 247 // In particular, null-checks and other low-level exceptions common up here. 248 Node* ex_oop = saved_ex_oop(ex_map); 249 const Type* ex_type = _gvn.type(ex_oop); 250 if (ex_oop == top()) { 251 // No action needed. 252 return; 253 } 254 assert(ex_type->isa_instptr(), "exception must be an instance"); 255 for (SafePointNode* e2 = _exceptions; e2 != NULL; e2 = e2->next_exception()) { 256 const Type* ex_type2 = _gvn.type(saved_ex_oop(e2)); 257 // We check sp also because call bytecodes can generate exceptions 258 // both before and after arguments are popped! 259 if (ex_type2 == ex_type 260 && e2->_jvms->sp() == ex_map->_jvms->sp()) { 261 combine_exception_states(ex_map, e2); 262 return; 263 } 264 } 265 266 // No pre-existing exception of the same type. Chain it on the list. 267 push_exception_state(ex_map); 268 } 269 270 //-----------------------add_exception_states_from----------------------------- 271 void GraphKit::add_exception_states_from(JVMState* jvms) { 272 SafePointNode* ex_map = jvms->map()->next_exception(); 273 if (ex_map != NULL) { 274 jvms->map()->set_next_exception(NULL); 275 for (SafePointNode* next_map; ex_map != NULL; ex_map = next_map) { 276 next_map = ex_map->next_exception(); 277 ex_map->set_next_exception(NULL); 278 add_exception_state(ex_map); 279 } 280 } 281 } 282 283 //-----------------------transfer_exceptions_into_jvms------------------------- 284 JVMState* GraphKit::transfer_exceptions_into_jvms() { 285 if (map() == NULL) { 286 // We need a JVMS to carry the exceptions, but the map has gone away. 287 // Create a scratch JVMS, cloned from any of the exception states... 288 if (has_exceptions()) { 289 _map = _exceptions; 290 _map = clone_map(); 291 _map->set_next_exception(NULL); 292 clear_saved_ex_oop(_map); 293 debug_only(verify_map()); 294 } else { 295 // ...or created from scratch 296 JVMState* jvms = new (C) JVMState(_method, NULL); 297 jvms->set_bci(_bci); 298 jvms->set_sp(_sp); 299 jvms->set_map(new SafePointNode(TypeFunc::Parms, jvms)); 300 set_jvms(jvms); 301 for (uint i = 0; i < map()->req(); i++) map()->init_req(i, top()); 302 set_all_memory(top()); 303 while (map()->req() < jvms->endoff()) map()->add_req(top()); 304 } 305 // (This is a kludge, in case you didn't notice.) 306 set_control(top()); 307 } 308 JVMState* jvms = sync_jvms(); 309 assert(!jvms->map()->has_exceptions(), "no exceptions on this map yet"); 310 jvms->map()->set_next_exception(_exceptions); 311 _exceptions = NULL; // done with this set of exceptions 312 return jvms; 313 } 314 315 static inline void add_n_reqs(Node* dstphi, Node* srcphi) { 316 assert(is_hidden_merge(dstphi), "must be a special merge node"); 317 assert(is_hidden_merge(srcphi), "must be a special merge node"); 318 uint limit = srcphi->req(); 319 for (uint i = PhiNode::Input; i < limit; i++) { 320 dstphi->add_req(srcphi->in(i)); 321 } 322 } 323 static inline void add_one_req(Node* dstphi, Node* src) { 324 assert(is_hidden_merge(dstphi), "must be a special merge node"); 325 assert(!is_hidden_merge(src), "must not be a special merge node"); 326 dstphi->add_req(src); 327 } 328 329 //-----------------------combine_exception_states------------------------------ 330 // This helper function combines exception states by building phis on a 331 // specially marked state-merging region. These regions and phis are 332 // untransformed, and can build up gradually. The region is marked by 333 // having a control input of its exception map, rather than NULL. Such 334 // regions do not appear except in this function, and in use_exception_state. 335 void GraphKit::combine_exception_states(SafePointNode* ex_map, SafePointNode* phi_map) { 336 if (failing()) return; // dying anyway... 337 JVMState* ex_jvms = ex_map->_jvms; 338 assert(ex_jvms->same_calls_as(phi_map->_jvms), "consistent call chains"); 339 assert(ex_jvms->stkoff() == phi_map->_jvms->stkoff(), "matching locals"); 340 assert(ex_jvms->sp() == phi_map->_jvms->sp(), "matching stack sizes"); 341 assert(ex_jvms->monoff() == phi_map->_jvms->monoff(), "matching JVMS"); 342 assert(ex_jvms->scloff() == phi_map->_jvms->scloff(), "matching scalar replaced objects"); 343 assert(ex_map->req() == phi_map->req(), "matching maps"); 344 uint tos = ex_jvms->stkoff() + ex_jvms->sp(); 345 Node* hidden_merge_mark = root(); 346 Node* region = phi_map->control(); 347 MergeMemNode* phi_mem = phi_map->merged_memory(); 348 MergeMemNode* ex_mem = ex_map->merged_memory(); 349 if (region->in(0) != hidden_merge_mark) { 350 // The control input is not (yet) a specially-marked region in phi_map. 351 // Make it so, and build some phis. 352 region = new RegionNode(2); 353 _gvn.set_type(region, Type::CONTROL); 354 region->set_req(0, hidden_merge_mark); // marks an internal ex-state 355 region->init_req(1, phi_map->control()); 356 phi_map->set_control(region); 357 Node* io_phi = PhiNode::make(region, phi_map->i_o(), Type::ABIO); 358 record_for_igvn(io_phi); 359 _gvn.set_type(io_phi, Type::ABIO); 360 phi_map->set_i_o(io_phi); 361 for (MergeMemStream mms(phi_mem); mms.next_non_empty(); ) { 362 Node* m = mms.memory(); 363 Node* m_phi = PhiNode::make(region, m, Type::MEMORY, mms.adr_type(C)); 364 record_for_igvn(m_phi); 365 _gvn.set_type(m_phi, Type::MEMORY); 366 mms.set_memory(m_phi); 367 } 368 } 369 370 // Either or both of phi_map and ex_map might already be converted into phis. 371 Node* ex_control = ex_map->control(); 372 // if there is special marking on ex_map also, we add multiple edges from src 373 bool add_multiple = (ex_control->in(0) == hidden_merge_mark); 374 // how wide was the destination phi_map, originally? 375 uint orig_width = region->req(); 376 377 if (add_multiple) { 378 add_n_reqs(region, ex_control); 379 add_n_reqs(phi_map->i_o(), ex_map->i_o()); 380 } else { 381 // ex_map has no merges, so we just add single edges everywhere 382 add_one_req(region, ex_control); 383 add_one_req(phi_map->i_o(), ex_map->i_o()); 384 } 385 for (MergeMemStream mms(phi_mem, ex_mem); mms.next_non_empty2(); ) { 386 if (mms.is_empty()) { 387 // get a copy of the base memory, and patch some inputs into it 388 const TypePtr* adr_type = mms.adr_type(C); 389 Node* phi = mms.force_memory()->as_Phi()->slice_memory(adr_type); 390 assert(phi->as_Phi()->region() == mms.base_memory()->in(0), ""); 391 mms.set_memory(phi); 392 // Prepare to append interesting stuff onto the newly sliced phi: 393 while (phi->req() > orig_width) phi->del_req(phi->req()-1); 394 } 395 // Append stuff from ex_map: 396 if (add_multiple) { 397 add_n_reqs(mms.memory(), mms.memory2()); 398 } else { 399 add_one_req(mms.memory(), mms.memory2()); 400 } 401 } 402 uint limit = ex_map->req(); 403 for (uint i = TypeFunc::Parms; i < limit; i++) { 404 // Skip everything in the JVMS after tos. (The ex_oop follows.) 405 if (i == tos) i = ex_jvms->monoff(); 406 Node* src = ex_map->in(i); 407 Node* dst = phi_map->in(i); 408 if (src != dst) { 409 PhiNode* phi; 410 if (dst->in(0) != region) { 411 dst = phi = PhiNode::make(region, dst, _gvn.type(dst)); 412 record_for_igvn(phi); 413 _gvn.set_type(phi, phi->type()); 414 phi_map->set_req(i, dst); 415 // Prepare to append interesting stuff onto the new phi: 416 while (dst->req() > orig_width) dst->del_req(dst->req()-1); 417 } else { 418 assert(dst->is_Phi(), "nobody else uses a hidden region"); 419 phi = dst->as_Phi(); 420 } 421 if (add_multiple && src->in(0) == ex_control) { 422 // Both are phis. 423 add_n_reqs(dst, src); 424 } else { 425 while (dst->req() < region->req()) add_one_req(dst, src); 426 } 427 const Type* srctype = _gvn.type(src); 428 if (phi->type() != srctype) { 429 const Type* dsttype = phi->type()->meet_speculative(srctype); 430 if (phi->type() != dsttype) { 431 phi->set_type(dsttype); 432 _gvn.set_type(phi, dsttype); 433 } 434 } 435 } 436 } 437 phi_map->merge_replaced_nodes_with(ex_map); 438 } 439 440 //--------------------------use_exception_state-------------------------------- 441 Node* GraphKit::use_exception_state(SafePointNode* phi_map) { 442 if (failing()) { stop(); return top(); } 443 Node* region = phi_map->control(); 444 Node* hidden_merge_mark = root(); 445 assert(phi_map->jvms()->map() == phi_map, "sanity: 1-1 relation"); 446 Node* ex_oop = clear_saved_ex_oop(phi_map); 447 if (region->in(0) == hidden_merge_mark) { 448 // Special marking for internal ex-states. Process the phis now. 449 region->set_req(0, region); // now it's an ordinary region 450 set_jvms(phi_map->jvms()); // ...so now we can use it as a map 451 // Note: Setting the jvms also sets the bci and sp. 452 set_control(_gvn.transform(region)); 453 uint tos = jvms()->stkoff() + sp(); 454 for (uint i = 1; i < tos; i++) { 455 Node* x = phi_map->in(i); 456 if (x->in(0) == region) { 457 assert(x->is_Phi(), "expected a special phi"); 458 phi_map->set_req(i, _gvn.transform(x)); 459 } 460 } 461 for (MergeMemStream mms(merged_memory()); mms.next_non_empty(); ) { 462 Node* x = mms.memory(); 463 if (x->in(0) == region) { 464 assert(x->is_Phi(), "nobody else uses a hidden region"); 465 mms.set_memory(_gvn.transform(x)); 466 } 467 } 468 if (ex_oop->in(0) == region) { 469 assert(ex_oop->is_Phi(), "expected a special phi"); 470 ex_oop = _gvn.transform(ex_oop); 471 } 472 } else { 473 set_jvms(phi_map->jvms()); 474 } 475 476 assert(!is_hidden_merge(phi_map->control()), "hidden ex. states cleared"); 477 assert(!is_hidden_merge(phi_map->i_o()), "hidden ex. states cleared"); 478 return ex_oop; 479 } 480 481 //---------------------------------java_bc------------------------------------- 482 Bytecodes::Code GraphKit::java_bc() const { 483 ciMethod* method = this->method(); 484 int bci = this->bci(); 485 if (method != NULL && bci != InvocationEntryBci) 486 return method->java_code_at_bci(bci); 487 else 488 return Bytecodes::_illegal; 489 } 490 491 void GraphKit::uncommon_trap_if_should_post_on_exceptions(Deoptimization::DeoptReason reason, 492 bool must_throw) { 493 // if the exception capability is set, then we will generate code 494 // to check the JavaThread.should_post_on_exceptions flag to see 495 // if we actually need to report exception events (for this 496 // thread). If we don't need to report exception events, we will 497 // take the normal fast path provided by add_exception_events. If 498 // exception event reporting is enabled for this thread, we will 499 // take the uncommon_trap in the BuildCutout below. 500 501 // first must access the should_post_on_exceptions_flag in this thread's JavaThread 502 Node* jthread = _gvn.transform(new ThreadLocalNode()); 503 Node* adr = basic_plus_adr(top(), jthread, in_bytes(JavaThread::should_post_on_exceptions_flag_offset())); 504 Node* should_post_flag = make_load(control(), adr, TypeInt::INT, T_INT, Compile::AliasIdxRaw, MemNode::unordered); 505 506 // Test the should_post_on_exceptions_flag vs. 0 507 Node* chk = _gvn.transform( new CmpINode(should_post_flag, intcon(0)) ); 508 Node* tst = _gvn.transform( new BoolNode(chk, BoolTest::eq) ); 509 510 // Branch to slow_path if should_post_on_exceptions_flag was true 511 { BuildCutout unless(this, tst, PROB_MAX); 512 // Do not try anything fancy if we're notifying the VM on every throw. 513 // Cf. case Bytecodes::_athrow in parse2.cpp. 514 uncommon_trap(reason, Deoptimization::Action_none, 515 (ciKlass*)NULL, (char*)NULL, must_throw); 516 } 517 518 } 519 520 //------------------------------builtin_throw---------------------------------- 521 void GraphKit::builtin_throw(Deoptimization::DeoptReason reason, Node* arg) { 522 bool must_throw = true; 523 524 if (env()->jvmti_can_post_on_exceptions()) { 525 // check if we must post exception events, take uncommon trap if so 526 uncommon_trap_if_should_post_on_exceptions(reason, must_throw); 527 // here if should_post_on_exceptions is false 528 // continue on with the normal codegen 529 } 530 531 // If this particular condition has not yet happened at this 532 // bytecode, then use the uncommon trap mechanism, and allow for 533 // a future recompilation if several traps occur here. 534 // If the throw is hot, try to use a more complicated inline mechanism 535 // which keeps execution inside the compiled code. 536 bool treat_throw_as_hot = false; 537 ciMethodData* md = method()->method_data(); 538 539 if (ProfileTraps) { 540 if (too_many_traps(reason)) { 541 treat_throw_as_hot = true; 542 } 543 // (If there is no MDO at all, assume it is early in 544 // execution, and that any deopts are part of the 545 // startup transient, and don't need to be remembered.) 546 547 // Also, if there is a local exception handler, treat all throws 548 // as hot if there has been at least one in this method. 549 if (C->trap_count(reason) != 0 550 && method()->method_data()->trap_count(reason) != 0 551 && has_ex_handler()) { 552 treat_throw_as_hot = true; 553 } 554 } 555 556 // If this throw happens frequently, an uncommon trap might cause 557 // a performance pothole. If there is a local exception handler, 558 // and if this particular bytecode appears to be deoptimizing often, 559 // let us handle the throw inline, with a preconstructed instance. 560 // Note: If the deopt count has blown up, the uncommon trap 561 // runtime is going to flush this nmethod, not matter what. 562 if (treat_throw_as_hot 563 && (!StackTraceInThrowable || OmitStackTraceInFastThrow)) { 564 // If the throw is local, we use a pre-existing instance and 565 // punt on the backtrace. This would lead to a missing backtrace 566 // (a repeat of 4292742) if the backtrace object is ever asked 567 // for its backtrace. 568 // Fixing this remaining case of 4292742 requires some flavor of 569 // escape analysis. Leave that for the future. 570 ciInstance* ex_obj = NULL; 571 switch (reason) { 572 case Deoptimization::Reason_null_check: 573 ex_obj = env()->NullPointerException_instance(); 574 break; 575 case Deoptimization::Reason_div0_check: 576 ex_obj = env()->ArithmeticException_instance(); 577 break; 578 case Deoptimization::Reason_range_check: 579 ex_obj = env()->ArrayIndexOutOfBoundsException_instance(); 580 break; 581 case Deoptimization::Reason_class_check: 582 if (java_bc() == Bytecodes::_aastore) { 583 ex_obj = env()->ArrayStoreException_instance(); 584 } else { 585 ex_obj = env()->ClassCastException_instance(); 586 } 587 break; 588 default: 589 break; 590 } 591 if (failing()) { stop(); return; } // exception allocation might fail 592 if (ex_obj != NULL) { 593 // Cheat with a preallocated exception object. 594 if (C->log() != NULL) 595 C->log()->elem("hot_throw preallocated='1' reason='%s'", 596 Deoptimization::trap_reason_name(reason)); 597 const TypeInstPtr* ex_con = TypeInstPtr::make(ex_obj); 598 Node* ex_node = _gvn.transform(ConNode::make(ex_con)); 599 600 // Clear the detail message of the preallocated exception object. 601 // Weblogic sometimes mutates the detail message of exceptions 602 // using reflection. 603 int offset = java_lang_Throwable::get_detailMessage_offset(); 604 const TypePtr* adr_typ = ex_con->add_offset(offset); 605 606 Node *adr = basic_plus_adr(ex_node, ex_node, offset); 607 const TypeOopPtr* val_type = TypeOopPtr::make_from_klass(env()->String_klass()); 608 Node *store = access_store_at(control(), ex_node, adr, adr_typ, null(), val_type, T_OBJECT, IN_HEAP); 609 610 add_exception_state(make_exception_state(ex_node)); 611 return; 612 } 613 } 614 615 // %%% Maybe add entry to OptoRuntime which directly throws the exc.? 616 // It won't be much cheaper than bailing to the interp., since we'll 617 // have to pass up all the debug-info, and the runtime will have to 618 // create the stack trace. 619 620 // Usual case: Bail to interpreter. 621 // Reserve the right to recompile if we haven't seen anything yet. 622 623 ciMethod* m = Deoptimization::reason_is_speculate(reason) ? C->method() : NULL; 624 Deoptimization::DeoptAction action = Deoptimization::Action_maybe_recompile; 625 if (treat_throw_as_hot 626 && (method()->method_data()->trap_recompiled_at(bci(), m) 627 || C->too_many_traps(reason))) { 628 // We cannot afford to take more traps here. Suffer in the interpreter. 629 if (C->log() != NULL) 630 C->log()->elem("hot_throw preallocated='0' reason='%s' mcount='%d'", 631 Deoptimization::trap_reason_name(reason), 632 C->trap_count(reason)); 633 action = Deoptimization::Action_none; 634 } 635 636 // "must_throw" prunes the JVM state to include only the stack, if there 637 // are no local exception handlers. This should cut down on register 638 // allocation time and code size, by drastically reducing the number 639 // of in-edges on the call to the uncommon trap. 640 641 uncommon_trap(reason, action, (ciKlass*)NULL, (char*)NULL, must_throw); 642 } 643 644 645 //----------------------------PreserveJVMState--------------------------------- 646 PreserveJVMState::PreserveJVMState(GraphKit* kit, bool clone_map) { 647 debug_only(kit->verify_map()); 648 _kit = kit; 649 _map = kit->map(); // preserve the map 650 _sp = kit->sp(); 651 kit->set_map(clone_map ? kit->clone_map() : NULL); 652 #ifdef ASSERT 653 _bci = kit->bci(); 654 Parse* parser = kit->is_Parse(); 655 int block = (parser == NULL || parser->block() == NULL) ? -1 : parser->block()->rpo(); 656 _block = block; 657 #endif 658 } 659 PreserveJVMState::~PreserveJVMState() { 660 GraphKit* kit = _kit; 661 #ifdef ASSERT 662 assert(kit->bci() == _bci, "bci must not shift"); 663 Parse* parser = kit->is_Parse(); 664 int block = (parser == NULL || parser->block() == NULL) ? -1 : parser->block()->rpo(); 665 assert(block == _block, "block must not shift"); 666 #endif 667 kit->set_map(_map); 668 kit->set_sp(_sp); 669 } 670 671 672 //-----------------------------BuildCutout------------------------------------- 673 BuildCutout::BuildCutout(GraphKit* kit, Node* p, float prob, float cnt) 674 : PreserveJVMState(kit) 675 { 676 assert(p->is_Con() || p->is_Bool(), "test must be a bool"); 677 SafePointNode* outer_map = _map; // preserved map is caller's 678 SafePointNode* inner_map = kit->map(); 679 IfNode* iff = kit->create_and_map_if(outer_map->control(), p, prob, cnt); 680 outer_map->set_control(kit->gvn().transform( new IfTrueNode(iff) )); 681 inner_map->set_control(kit->gvn().transform( new IfFalseNode(iff) )); 682 } 683 BuildCutout::~BuildCutout() { 684 GraphKit* kit = _kit; 685 assert(kit->stopped(), "cutout code must stop, throw, return, etc."); 686 } 687 688 //---------------------------PreserveReexecuteState---------------------------- 689 PreserveReexecuteState::PreserveReexecuteState(GraphKit* kit) { 690 assert(!kit->stopped(), "must call stopped() before"); 691 _kit = kit; 692 _sp = kit->sp(); 693 _reexecute = kit->jvms()->_reexecute; 694 } 695 PreserveReexecuteState::~PreserveReexecuteState() { 696 if (_kit->stopped()) return; 697 _kit->jvms()->_reexecute = _reexecute; 698 _kit->set_sp(_sp); 699 } 700 701 //------------------------------clone_map-------------------------------------- 702 // Implementation of PreserveJVMState 703 // 704 // Only clone_map(...) here. If this function is only used in the 705 // PreserveJVMState class we may want to get rid of this extra 706 // function eventually and do it all there. 707 708 SafePointNode* GraphKit::clone_map() { 709 if (map() == NULL) return NULL; 710 711 // Clone the memory edge first 712 Node* mem = MergeMemNode::make(map()->memory()); 713 gvn().set_type_bottom(mem); 714 715 SafePointNode *clonemap = (SafePointNode*)map()->clone(); 716 JVMState* jvms = this->jvms(); 717 JVMState* clonejvms = jvms->clone_shallow(C); 718 clonemap->set_memory(mem); 719 clonemap->set_jvms(clonejvms); 720 clonejvms->set_map(clonemap); 721 record_for_igvn(clonemap); 722 gvn().set_type_bottom(clonemap); 723 return clonemap; 724 } 725 726 727 //-----------------------------set_map_clone----------------------------------- 728 void GraphKit::set_map_clone(SafePointNode* m) { 729 _map = m; 730 _map = clone_map(); 731 _map->set_next_exception(NULL); 732 debug_only(verify_map()); 733 } 734 735 736 //----------------------------kill_dead_locals--------------------------------- 737 // Detect any locals which are known to be dead, and force them to top. 738 void GraphKit::kill_dead_locals() { 739 // Consult the liveness information for the locals. If any 740 // of them are unused, then they can be replaced by top(). This 741 // should help register allocation time and cut down on the size 742 // of the deoptimization information. 743 744 // This call is made from many of the bytecode handling 745 // subroutines called from the Big Switch in do_one_bytecode. 746 // Every bytecode which might include a slow path is responsible 747 // for killing its dead locals. The more consistent we 748 // are about killing deads, the fewer useless phis will be 749 // constructed for them at various merge points. 750 751 // bci can be -1 (InvocationEntryBci). We return the entry 752 // liveness for the method. 753 754 if (method() == NULL || method()->code_size() == 0) { 755 // We are building a graph for a call to a native method. 756 // All locals are live. 757 return; 758 } 759 760 ResourceMark rm; 761 762 // Consult the liveness information for the locals. If any 763 // of them are unused, then they can be replaced by top(). This 764 // should help register allocation time and cut down on the size 765 // of the deoptimization information. 766 MethodLivenessResult live_locals = method()->liveness_at_bci(bci()); 767 768 int len = (int)live_locals.size(); 769 assert(len <= jvms()->loc_size(), "too many live locals"); 770 for (int local = 0; local < len; local++) { 771 if (!live_locals.at(local)) { 772 set_local(local, top()); 773 } 774 } 775 } 776 777 #ifdef ASSERT 778 //-------------------------dead_locals_are_killed------------------------------ 779 // Return true if all dead locals are set to top in the map. 780 // Used to assert "clean" debug info at various points. 781 bool GraphKit::dead_locals_are_killed() { 782 if (method() == NULL || method()->code_size() == 0) { 783 // No locals need to be dead, so all is as it should be. 784 return true; 785 } 786 787 // Make sure somebody called kill_dead_locals upstream. 788 ResourceMark rm; 789 for (JVMState* jvms = this->jvms(); jvms != NULL; jvms = jvms->caller()) { 790 if (jvms->loc_size() == 0) continue; // no locals to consult 791 SafePointNode* map = jvms->map(); 792 ciMethod* method = jvms->method(); 793 int bci = jvms->bci(); 794 if (jvms == this->jvms()) { 795 bci = this->bci(); // it might not yet be synched 796 } 797 MethodLivenessResult live_locals = method->liveness_at_bci(bci); 798 int len = (int)live_locals.size(); 799 if (!live_locals.is_valid() || len == 0) 800 // This method is trivial, or is poisoned by a breakpoint. 801 return true; 802 assert(len == jvms->loc_size(), "live map consistent with locals map"); 803 for (int local = 0; local < len; local++) { 804 if (!live_locals.at(local) && map->local(jvms, local) != top()) { 805 if (PrintMiscellaneous && (Verbose || WizardMode)) { 806 tty->print_cr("Zombie local %d: ", local); 807 jvms->dump(); 808 } 809 return false; 810 } 811 } 812 } 813 return true; 814 } 815 816 #endif //ASSERT 817 818 // Helper function for enforcing certain bytecodes to reexecute if 819 // deoptimization happens 820 static bool should_reexecute_implied_by_bytecode(JVMState *jvms, bool is_anewarray) { 821 ciMethod* cur_method = jvms->method(); 822 int cur_bci = jvms->bci(); 823 if (cur_method != NULL && cur_bci != InvocationEntryBci) { 824 Bytecodes::Code code = cur_method->java_code_at_bci(cur_bci); 825 return Interpreter::bytecode_should_reexecute(code) || 826 (is_anewarray && code == Bytecodes::_multianewarray); 827 // Reexecute _multianewarray bytecode which was replaced with 828 // sequence of [a]newarray. See Parse::do_multianewarray(). 829 // 830 // Note: interpreter should not have it set since this optimization 831 // is limited by dimensions and guarded by flag so in some cases 832 // multianewarray() runtime calls will be generated and 833 // the bytecode should not be reexecutes (stack will not be reset). 834 } else 835 return false; 836 } 837 838 // Helper function for adding JVMState and debug information to node 839 void GraphKit::add_safepoint_edges(SafePointNode* call, bool must_throw) { 840 // Add the safepoint edges to the call (or other safepoint). 841 842 // Make sure dead locals are set to top. This 843 // should help register allocation time and cut down on the size 844 // of the deoptimization information. 845 assert(dead_locals_are_killed(), "garbage in debug info before safepoint"); 846 847 // Walk the inline list to fill in the correct set of JVMState's 848 // Also fill in the associated edges for each JVMState. 849 850 // If the bytecode needs to be reexecuted we need to put 851 // the arguments back on the stack. 852 const bool should_reexecute = jvms()->should_reexecute(); 853 JVMState* youngest_jvms = should_reexecute ? sync_jvms_for_reexecute() : sync_jvms(); 854 855 // NOTE: set_bci (called from sync_jvms) might reset the reexecute bit to 856 // undefined if the bci is different. This is normal for Parse but it 857 // should not happen for LibraryCallKit because only one bci is processed. 858 assert(!is_LibraryCallKit() || (jvms()->should_reexecute() == should_reexecute), 859 "in LibraryCallKit the reexecute bit should not change"); 860 861 // If we are guaranteed to throw, we can prune everything but the 862 // input to the current bytecode. 863 bool can_prune_locals = false; 864 uint stack_slots_not_pruned = 0; 865 int inputs = 0, depth = 0; 866 if (must_throw) { 867 assert(method() == youngest_jvms->method(), "sanity"); 868 if (compute_stack_effects(inputs, depth)) { 869 can_prune_locals = true; 870 stack_slots_not_pruned = inputs; 871 } 872 } 873 874 if (env()->should_retain_local_variables()) { 875 // At any safepoint, this method can get breakpointed, which would 876 // then require an immediate deoptimization. 877 can_prune_locals = false; // do not prune locals 878 stack_slots_not_pruned = 0; 879 } 880 881 // do not scribble on the input jvms 882 JVMState* out_jvms = youngest_jvms->clone_deep(C); 883 call->set_jvms(out_jvms); // Start jvms list for call node 884 885 // For a known set of bytecodes, the interpreter should reexecute them if 886 // deoptimization happens. We set the reexecute state for them here 887 if (out_jvms->is_reexecute_undefined() && //don't change if already specified 888 should_reexecute_implied_by_bytecode(out_jvms, call->is_AllocateArray())) { 889 out_jvms->set_should_reexecute(true); //NOTE: youngest_jvms not changed 890 } 891 892 // Presize the call: 893 DEBUG_ONLY(uint non_debug_edges = call->req()); 894 call->add_req_batch(top(), youngest_jvms->debug_depth()); 895 assert(call->req() == non_debug_edges + youngest_jvms->debug_depth(), ""); 896 897 // Set up edges so that the call looks like this: 898 // Call [state:] ctl io mem fptr retadr 899 // [parms:] parm0 ... parmN 900 // [root:] loc0 ... locN stk0 ... stkSP mon0 obj0 ... monN objN 901 // [...mid:] loc0 ... locN stk0 ... stkSP mon0 obj0 ... monN objN [...] 902 // [young:] loc0 ... locN stk0 ... stkSP mon0 obj0 ... monN objN 903 // Note that caller debug info precedes callee debug info. 904 905 // Fill pointer walks backwards from "young:" to "root:" in the diagram above: 906 uint debug_ptr = call->req(); 907 908 // Loop over the map input edges associated with jvms, add them 909 // to the call node, & reset all offsets to match call node array. 910 for (JVMState* in_jvms = youngest_jvms; in_jvms != NULL; ) { 911 uint debug_end = debug_ptr; 912 uint debug_start = debug_ptr - in_jvms->debug_size(); 913 debug_ptr = debug_start; // back up the ptr 914 915 uint p = debug_start; // walks forward in [debug_start, debug_end) 916 uint j, k, l; 917 SafePointNode* in_map = in_jvms->map(); 918 out_jvms->set_map(call); 919 920 if (can_prune_locals) { 921 assert(in_jvms->method() == out_jvms->method(), "sanity"); 922 // If the current throw can reach an exception handler in this JVMS, 923 // then we must keep everything live that can reach that handler. 924 // As a quick and dirty approximation, we look for any handlers at all. 925 if (in_jvms->method()->has_exception_handlers()) { 926 can_prune_locals = false; 927 } 928 } 929 930 // Add the Locals 931 k = in_jvms->locoff(); 932 l = in_jvms->loc_size(); 933 out_jvms->set_locoff(p); 934 if (!can_prune_locals) { 935 for (j = 0; j < l; j++) 936 call->set_req(p++, in_map->in(k+j)); 937 } else { 938 p += l; // already set to top above by add_req_batch 939 } 940 941 // Add the Expression Stack 942 k = in_jvms->stkoff(); 943 l = in_jvms->sp(); 944 out_jvms->set_stkoff(p); 945 if (!can_prune_locals) { 946 for (j = 0; j < l; j++) 947 call->set_req(p++, in_map->in(k+j)); 948 } else if (can_prune_locals && stack_slots_not_pruned != 0) { 949 // Divide stack into {S0,...,S1}, where S0 is set to top. 950 uint s1 = stack_slots_not_pruned; 951 stack_slots_not_pruned = 0; // for next iteration 952 if (s1 > l) s1 = l; 953 uint s0 = l - s1; 954 p += s0; // skip the tops preinstalled by add_req_batch 955 for (j = s0; j < l; j++) 956 call->set_req(p++, in_map->in(k+j)); 957 } else { 958 p += l; // already set to top above by add_req_batch 959 } 960 961 // Add the Monitors 962 k = in_jvms->monoff(); 963 l = in_jvms->mon_size(); 964 out_jvms->set_monoff(p); 965 for (j = 0; j < l; j++) 966 call->set_req(p++, in_map->in(k+j)); 967 968 // Copy any scalar object fields. 969 k = in_jvms->scloff(); 970 l = in_jvms->scl_size(); 971 out_jvms->set_scloff(p); 972 for (j = 0; j < l; j++) 973 call->set_req(p++, in_map->in(k+j)); 974 975 // Finish the new jvms. 976 out_jvms->set_endoff(p); 977 978 assert(out_jvms->endoff() == debug_end, "fill ptr must match"); 979 assert(out_jvms->depth() == in_jvms->depth(), "depth must match"); 980 assert(out_jvms->loc_size() == in_jvms->loc_size(), "size must match"); 981 assert(out_jvms->mon_size() == in_jvms->mon_size(), "size must match"); 982 assert(out_jvms->scl_size() == in_jvms->scl_size(), "size must match"); 983 assert(out_jvms->debug_size() == in_jvms->debug_size(), "size must match"); 984 985 // Update the two tail pointers in parallel. 986 out_jvms = out_jvms->caller(); 987 in_jvms = in_jvms->caller(); 988 } 989 990 assert(debug_ptr == non_debug_edges, "debug info must fit exactly"); 991 992 // Test the correctness of JVMState::debug_xxx accessors: 993 assert(call->jvms()->debug_start() == non_debug_edges, ""); 994 assert(call->jvms()->debug_end() == call->req(), ""); 995 assert(call->jvms()->debug_depth() == call->req() - non_debug_edges, ""); 996 } 997 998 bool GraphKit::compute_stack_effects(int& inputs, int& depth) { 999 Bytecodes::Code code = java_bc(); 1000 if (code == Bytecodes::_wide) { 1001 code = method()->java_code_at_bci(bci() + 1); 1002 } 1003 1004 BasicType rtype = T_ILLEGAL; 1005 int rsize = 0; 1006 1007 if (code != Bytecodes::_illegal) { 1008 depth = Bytecodes::depth(code); // checkcast=0, athrow=-1 1009 rtype = Bytecodes::result_type(code); // checkcast=P, athrow=V 1010 if (rtype < T_CONFLICT) 1011 rsize = type2size[rtype]; 1012 } 1013 1014 switch (code) { 1015 case Bytecodes::_illegal: 1016 return false; 1017 1018 case Bytecodes::_ldc: 1019 case Bytecodes::_ldc_w: 1020 case Bytecodes::_ldc2_w: 1021 inputs = 0; 1022 break; 1023 1024 case Bytecodes::_dup: inputs = 1; break; 1025 case Bytecodes::_dup_x1: inputs = 2; break; 1026 case Bytecodes::_dup_x2: inputs = 3; break; 1027 case Bytecodes::_dup2: inputs = 2; break; 1028 case Bytecodes::_dup2_x1: inputs = 3; break; 1029 case Bytecodes::_dup2_x2: inputs = 4; break; 1030 case Bytecodes::_swap: inputs = 2; break; 1031 case Bytecodes::_arraylength: inputs = 1; break; 1032 1033 case Bytecodes::_getstatic: 1034 case Bytecodes::_putstatic: 1035 case Bytecodes::_getfield: 1036 case Bytecodes::_putfield: 1037 { 1038 bool ignored_will_link; 1039 ciField* field = method()->get_field_at_bci(bci(), ignored_will_link); 1040 int size = field->type()->size(); 1041 bool is_get = (depth >= 0), is_static = (depth & 1); 1042 inputs = (is_static ? 0 : 1); 1043 if (is_get) { 1044 depth = size - inputs; 1045 } else { 1046 inputs += size; // putxxx pops the value from the stack 1047 depth = - inputs; 1048 } 1049 } 1050 break; 1051 1052 case Bytecodes::_invokevirtual: 1053 case Bytecodes::_invokespecial: 1054 case Bytecodes::_invokestatic: 1055 case Bytecodes::_invokedynamic: 1056 case Bytecodes::_invokeinterface: 1057 { 1058 bool ignored_will_link; 1059 ciSignature* declared_signature = NULL; 1060 ciMethod* ignored_callee = method()->get_method_at_bci(bci(), ignored_will_link, &declared_signature); 1061 assert(declared_signature != NULL, "cannot be null"); 1062 inputs = declared_signature->arg_size_for_bc(code); 1063 int size = declared_signature->return_type()->size(); 1064 depth = size - inputs; 1065 } 1066 break; 1067 1068 case Bytecodes::_multianewarray: 1069 { 1070 ciBytecodeStream iter(method()); 1071 iter.reset_to_bci(bci()); 1072 iter.next(); 1073 inputs = iter.get_dimensions(); 1074 assert(rsize == 1, ""); 1075 depth = rsize - inputs; 1076 } 1077 break; 1078 1079 case Bytecodes::_ireturn: 1080 case Bytecodes::_lreturn: 1081 case Bytecodes::_freturn: 1082 case Bytecodes::_dreturn: 1083 case Bytecodes::_areturn: 1084 assert(rsize == -depth, ""); 1085 inputs = rsize; 1086 break; 1087 1088 case Bytecodes::_jsr: 1089 case Bytecodes::_jsr_w: 1090 inputs = 0; 1091 depth = 1; // S.B. depth=1, not zero 1092 break; 1093 1094 default: 1095 // bytecode produces a typed result 1096 inputs = rsize - depth; 1097 assert(inputs >= 0, ""); 1098 break; 1099 } 1100 1101 #ifdef ASSERT 1102 // spot check 1103 int outputs = depth + inputs; 1104 assert(outputs >= 0, "sanity"); 1105 switch (code) { 1106 case Bytecodes::_checkcast: assert(inputs == 1 && outputs == 1, ""); break; 1107 case Bytecodes::_athrow: assert(inputs == 1 && outputs == 0, ""); break; 1108 case Bytecodes::_aload_0: assert(inputs == 0 && outputs == 1, ""); break; 1109 case Bytecodes::_return: assert(inputs == 0 && outputs == 0, ""); break; 1110 case Bytecodes::_drem: assert(inputs == 4 && outputs == 2, ""); break; 1111 default: break; 1112 } 1113 #endif //ASSERT 1114 1115 return true; 1116 } 1117 1118 1119 1120 //------------------------------basic_plus_adr--------------------------------- 1121 Node* GraphKit::basic_plus_adr(Node* base, Node* ptr, Node* offset) { 1122 // short-circuit a common case 1123 if (offset == intcon(0)) return ptr; 1124 return _gvn.transform( new AddPNode(base, ptr, offset) ); 1125 } 1126 1127 Node* GraphKit::ConvI2L(Node* offset) { 1128 // short-circuit a common case 1129 jint offset_con = find_int_con(offset, Type::OffsetBot); 1130 if (offset_con != Type::OffsetBot) { 1131 return longcon((jlong) offset_con); 1132 } 1133 return _gvn.transform( new ConvI2LNode(offset)); 1134 } 1135 1136 Node* GraphKit::ConvI2UL(Node* offset) { 1137 juint offset_con = (juint) find_int_con(offset, Type::OffsetBot); 1138 if (offset_con != (juint) Type::OffsetBot) { 1139 return longcon((julong) offset_con); 1140 } 1141 Node* conv = _gvn.transform( new ConvI2LNode(offset)); 1142 Node* mask = _gvn.transform(ConLNode::make((julong) max_juint)); 1143 return _gvn.transform( new AndLNode(conv, mask) ); 1144 } 1145 1146 Node* GraphKit::ConvL2I(Node* offset) { 1147 // short-circuit a common case 1148 jlong offset_con = find_long_con(offset, (jlong)Type::OffsetBot); 1149 if (offset_con != (jlong)Type::OffsetBot) { 1150 return intcon((int) offset_con); 1151 } 1152 return _gvn.transform( new ConvL2INode(offset)); 1153 } 1154 1155 //-------------------------load_object_klass----------------------------------- 1156 Node* GraphKit::load_object_klass(Node* obj) { 1157 // Special-case a fresh allocation to avoid building nodes: 1158 Node* akls = AllocateNode::Ideal_klass(obj, &_gvn); 1159 if (akls != NULL) return akls; 1160 Node* k_adr = basic_plus_adr(obj, oopDesc::klass_offset_in_bytes()); 1161 return _gvn.transform(LoadKlassNode::make(_gvn, NULL, immutable_memory(), k_adr, TypeInstPtr::KLASS)); 1162 } 1163 1164 //-------------------------load_array_length----------------------------------- 1165 Node* GraphKit::load_array_length(Node* array) { 1166 // Special-case a fresh allocation to avoid building nodes: 1167 AllocateArrayNode* alloc = AllocateArrayNode::Ideal_array_allocation(array, &_gvn); 1168 Node *alen; 1169 if (alloc == NULL) { 1170 Node *r_adr = basic_plus_adr(array, arrayOopDesc::length_offset_in_bytes()); 1171 alen = _gvn.transform( new LoadRangeNode(0, immutable_memory(), r_adr, TypeInt::POS)); 1172 } else { 1173 alen = alloc->Ideal_length(); 1174 Node* ccast = alloc->make_ideal_length(_gvn.type(array)->is_oopptr(), &_gvn); 1175 if (ccast != alen) { 1176 alen = _gvn.transform(ccast); 1177 } 1178 } 1179 return alen; 1180 } 1181 1182 //------------------------------do_null_check---------------------------------- 1183 // Helper function to do a NULL pointer check. Returned value is 1184 // the incoming address with NULL casted away. You are allowed to use the 1185 // not-null value only if you are control dependent on the test. 1186 #ifndef PRODUCT 1187 extern int explicit_null_checks_inserted, 1188 explicit_null_checks_elided; 1189 #endif 1190 Node* GraphKit::null_check_common(Node* value, BasicType type, 1191 // optional arguments for variations: 1192 bool assert_null, 1193 Node* *null_control, 1194 bool speculative) { 1195 assert(!assert_null || null_control == NULL, "not both at once"); 1196 if (stopped()) return top(); 1197 NOT_PRODUCT(explicit_null_checks_inserted++); 1198 1199 // Construct NULL check 1200 Node *chk = NULL; 1201 switch(type) { 1202 case T_LONG : chk = new CmpLNode(value, _gvn.zerocon(T_LONG)); break; 1203 case T_INT : chk = new CmpINode(value, _gvn.intcon(0)); break; 1204 case T_ARRAY : // fall through 1205 type = T_OBJECT; // simplify further tests 1206 case T_OBJECT : { 1207 const Type *t = _gvn.type( value ); 1208 1209 const TypeOopPtr* tp = t->isa_oopptr(); 1210 if (tp != NULL && tp->klass() != NULL && !tp->klass()->is_loaded() 1211 // Only for do_null_check, not any of its siblings: 1212 && !assert_null && null_control == NULL) { 1213 // Usually, any field access or invocation on an unloaded oop type 1214 // will simply fail to link, since the statically linked class is 1215 // likely also to be unloaded. However, in -Xcomp mode, sometimes 1216 // the static class is loaded but the sharper oop type is not. 1217 // Rather than checking for this obscure case in lots of places, 1218 // we simply observe that a null check on an unloaded class 1219 // will always be followed by a nonsense operation, so we 1220 // can just issue the uncommon trap here. 1221 // Our access to the unloaded class will only be correct 1222 // after it has been loaded and initialized, which requires 1223 // a trip through the interpreter. 1224 #ifndef PRODUCT 1225 if (WizardMode) { tty->print("Null check of unloaded "); tp->klass()->print(); tty->cr(); } 1226 #endif 1227 uncommon_trap(Deoptimization::Reason_unloaded, 1228 Deoptimization::Action_reinterpret, 1229 tp->klass(), "!loaded"); 1230 return top(); 1231 } 1232 1233 if (assert_null) { 1234 // See if the type is contained in NULL_PTR. 1235 // If so, then the value is already null. 1236 if (t->higher_equal(TypePtr::NULL_PTR)) { 1237 NOT_PRODUCT(explicit_null_checks_elided++); 1238 return value; // Elided null assert quickly! 1239 } 1240 } else { 1241 // See if mixing in the NULL pointer changes type. 1242 // If so, then the NULL pointer was not allowed in the original 1243 // type. In other words, "value" was not-null. 1244 if (t->meet(TypePtr::NULL_PTR) != t->remove_speculative()) { 1245 // same as: if (!TypePtr::NULL_PTR->higher_equal(t)) ... 1246 NOT_PRODUCT(explicit_null_checks_elided++); 1247 return value; // Elided null check quickly! 1248 } 1249 } 1250 chk = new CmpPNode( value, null() ); 1251 break; 1252 } 1253 1254 default: 1255 fatal("unexpected type: %s", type2name(type)); 1256 } 1257 assert(chk != NULL, "sanity check"); 1258 chk = _gvn.transform(chk); 1259 1260 BoolTest::mask btest = assert_null ? BoolTest::eq : BoolTest::ne; 1261 BoolNode *btst = new BoolNode( chk, btest); 1262 Node *tst = _gvn.transform( btst ); 1263 1264 //----------- 1265 // if peephole optimizations occurred, a prior test existed. 1266 // If a prior test existed, maybe it dominates as we can avoid this test. 1267 if (tst != btst && type == T_OBJECT) { 1268 // At this point we want to scan up the CFG to see if we can 1269 // find an identical test (and so avoid this test altogether). 1270 Node *cfg = control(); 1271 int depth = 0; 1272 while( depth < 16 ) { // Limit search depth for speed 1273 if( cfg->Opcode() == Op_IfTrue && 1274 cfg->in(0)->in(1) == tst ) { 1275 // Found prior test. Use "cast_not_null" to construct an identical 1276 // CastPP (and hence hash to) as already exists for the prior test. 1277 // Return that casted value. 1278 if (assert_null) { 1279 replace_in_map(value, null()); 1280 return null(); // do not issue the redundant test 1281 } 1282 Node *oldcontrol = control(); 1283 set_control(cfg); 1284 Node *res = cast_not_null(value); 1285 set_control(oldcontrol); 1286 NOT_PRODUCT(explicit_null_checks_elided++); 1287 return res; 1288 } 1289 cfg = IfNode::up_one_dom(cfg, /*linear_only=*/ true); 1290 if (cfg == NULL) break; // Quit at region nodes 1291 depth++; 1292 } 1293 } 1294 1295 //----------- 1296 // Branch to failure if null 1297 float ok_prob = PROB_MAX; // a priori estimate: nulls never happen 1298 Deoptimization::DeoptReason reason; 1299 if (assert_null) { 1300 reason = Deoptimization::reason_null_assert(speculative); 1301 } else if (type == T_OBJECT) { 1302 reason = Deoptimization::reason_null_check(speculative); 1303 } else { 1304 reason = Deoptimization::Reason_div0_check; 1305 } 1306 // %%% Since Reason_unhandled is not recorded on a per-bytecode basis, 1307 // ciMethodData::has_trap_at will return a conservative -1 if any 1308 // must-be-null assertion has failed. This could cause performance 1309 // problems for a method after its first do_null_assert failure. 1310 // Consider using 'Reason_class_check' instead? 1311 1312 // To cause an implicit null check, we set the not-null probability 1313 // to the maximum (PROB_MAX). For an explicit check the probability 1314 // is set to a smaller value. 1315 if (null_control != NULL || too_many_traps(reason)) { 1316 // probability is less likely 1317 ok_prob = PROB_LIKELY_MAG(3); 1318 } else if (!assert_null && 1319 (ImplicitNullCheckThreshold > 0) && 1320 method() != NULL && 1321 (method()->method_data()->trap_count(reason) 1322 >= (uint)ImplicitNullCheckThreshold)) { 1323 ok_prob = PROB_LIKELY_MAG(3); 1324 } 1325 1326 if (null_control != NULL) { 1327 IfNode* iff = create_and_map_if(control(), tst, ok_prob, COUNT_UNKNOWN); 1328 Node* null_true = _gvn.transform( new IfFalseNode(iff)); 1329 set_control( _gvn.transform( new IfTrueNode(iff))); 1330 #ifndef PRODUCT 1331 if (null_true == top()) { 1332 explicit_null_checks_elided++; 1333 } 1334 #endif 1335 (*null_control) = null_true; 1336 } else { 1337 BuildCutout unless(this, tst, ok_prob); 1338 // Check for optimizer eliding test at parse time 1339 if (stopped()) { 1340 // Failure not possible; do not bother making uncommon trap. 1341 NOT_PRODUCT(explicit_null_checks_elided++); 1342 } else if (assert_null) { 1343 uncommon_trap(reason, 1344 Deoptimization::Action_make_not_entrant, 1345 NULL, "assert_null"); 1346 } else { 1347 replace_in_map(value, zerocon(type)); 1348 builtin_throw(reason); 1349 } 1350 } 1351 1352 // Must throw exception, fall-thru not possible? 1353 if (stopped()) { 1354 return top(); // No result 1355 } 1356 1357 if (assert_null) { 1358 // Cast obj to null on this path. 1359 replace_in_map(value, zerocon(type)); 1360 return zerocon(type); 1361 } 1362 1363 // Cast obj to not-null on this path, if there is no null_control. 1364 // (If there is a null_control, a non-null value may come back to haunt us.) 1365 if (type == T_OBJECT) { 1366 Node* cast = cast_not_null(value, false); 1367 if (null_control == NULL || (*null_control) == top()) 1368 replace_in_map(value, cast); 1369 value = cast; 1370 } 1371 1372 return value; 1373 } 1374 1375 1376 //------------------------------cast_not_null---------------------------------- 1377 // Cast obj to not-null on this path 1378 Node* GraphKit::cast_not_null(Node* obj, bool do_replace_in_map) { 1379 const Type *t = _gvn.type(obj); 1380 const Type *t_not_null = t->join_speculative(TypePtr::NOTNULL); 1381 // Object is already not-null? 1382 if( t == t_not_null ) return obj; 1383 1384 Node *cast = new CastPPNode(obj,t_not_null); 1385 cast->init_req(0, control()); 1386 cast = _gvn.transform( cast ); 1387 1388 // Scan for instances of 'obj' in the current JVM mapping. 1389 // These instances are known to be not-null after the test. 1390 if (do_replace_in_map) 1391 replace_in_map(obj, cast); 1392 1393 return cast; // Return casted value 1394 } 1395 1396 // Sometimes in intrinsics, we implicitly know an object is not null 1397 // (there's no actual null check) so we can cast it to not null. In 1398 // the course of optimizations, the input to the cast can become null. 1399 // In that case that data path will die and we need the control path 1400 // to become dead as well to keep the graph consistent. So we have to 1401 // add a check for null for which one branch can't be taken. It uses 1402 // an Opaque4 node that will cause the check to be removed after loop 1403 // opts so the test goes away and the compiled code doesn't execute a 1404 // useless check. 1405 Node* GraphKit::must_be_not_null(Node* value, bool do_replace_in_map) { 1406 Node* chk = _gvn.transform(new CmpPNode(value, null())); 1407 Node *tst = _gvn.transform(new BoolNode(chk, BoolTest::ne)); 1408 Node* opaq = _gvn.transform(new Opaque4Node(C, tst, intcon(1))); 1409 IfNode *iff = new IfNode(control(), opaq, PROB_MAX, COUNT_UNKNOWN); 1410 _gvn.set_type(iff, iff->Value(&_gvn)); 1411 Node *if_f = _gvn.transform(new IfFalseNode(iff)); 1412 Node *frame = _gvn.transform(new ParmNode(C->start(), TypeFunc::FramePtr)); 1413 Node *halt = _gvn.transform(new HaltNode(if_f, frame)); 1414 C->root()->add_req(halt); 1415 Node *if_t = _gvn.transform(new IfTrueNode(iff)); 1416 set_control(if_t); 1417 return cast_not_null(value, do_replace_in_map); 1418 } 1419 1420 1421 //--------------------------replace_in_map------------------------------------- 1422 void GraphKit::replace_in_map(Node* old, Node* neww) { 1423 if (old == neww) { 1424 return; 1425 } 1426 1427 map()->replace_edge(old, neww); 1428 1429 // Note: This operation potentially replaces any edge 1430 // on the map. This includes locals, stack, and monitors 1431 // of the current (innermost) JVM state. 1432 1433 // don't let inconsistent types from profiling escape this 1434 // method 1435 1436 const Type* told = _gvn.type(old); 1437 const Type* tnew = _gvn.type(neww); 1438 1439 if (!tnew->higher_equal(told)) { 1440 return; 1441 } 1442 1443 map()->record_replaced_node(old, neww); 1444 } 1445 1446 1447 //============================================================================= 1448 //--------------------------------memory--------------------------------------- 1449 Node* GraphKit::memory(uint alias_idx) { 1450 MergeMemNode* mem = merged_memory(); 1451 Node* p = mem->memory_at(alias_idx); 1452 _gvn.set_type(p, Type::MEMORY); // must be mapped 1453 return p; 1454 } 1455 1456 //-----------------------------reset_memory------------------------------------ 1457 Node* GraphKit::reset_memory() { 1458 Node* mem = map()->memory(); 1459 // do not use this node for any more parsing! 1460 debug_only( map()->set_memory((Node*)NULL) ); 1461 return _gvn.transform( mem ); 1462 } 1463 1464 //------------------------------set_all_memory--------------------------------- 1465 void GraphKit::set_all_memory(Node* newmem) { 1466 Node* mergemem = MergeMemNode::make(newmem); 1467 gvn().set_type_bottom(mergemem); 1468 map()->set_memory(mergemem); 1469 } 1470 1471 //------------------------------set_all_memory_call---------------------------- 1472 void GraphKit::set_all_memory_call(Node* call, bool separate_io_proj) { 1473 Node* newmem = _gvn.transform( new ProjNode(call, TypeFunc::Memory, separate_io_proj) ); 1474 set_all_memory(newmem); 1475 } 1476 1477 //============================================================================= 1478 // 1479 // parser factory methods for MemNodes 1480 // 1481 // These are layered on top of the factory methods in LoadNode and StoreNode, 1482 // and integrate with the parser's memory state and _gvn engine. 1483 // 1484 1485 // factory methods in "int adr_idx" 1486 Node* GraphKit::make_load(Node* ctl, Node* adr, const Type* t, BasicType bt, 1487 int adr_idx, 1488 MemNode::MemOrd mo, 1489 LoadNode::ControlDependency control_dependency, 1490 bool require_atomic_access, 1491 bool unaligned, 1492 bool mismatched) { 1493 assert(adr_idx != Compile::AliasIdxTop, "use other make_load factory" ); 1494 const TypePtr* adr_type = NULL; // debug-mode-only argument 1495 debug_only(adr_type = C->get_adr_type(adr_idx)); 1496 Node* mem = memory(adr_idx); 1497 Node* ld; 1498 if (require_atomic_access && bt == T_LONG) { 1499 ld = LoadLNode::make_atomic(ctl, mem, adr, adr_type, t, mo, control_dependency, unaligned, mismatched); 1500 } else if (require_atomic_access && bt == T_DOUBLE) { 1501 ld = LoadDNode::make_atomic(ctl, mem, adr, adr_type, t, mo, control_dependency, unaligned, mismatched); 1502 } else { 1503 ld = LoadNode::make(_gvn, ctl, mem, adr, adr_type, t, bt, mo, control_dependency, unaligned, mismatched); 1504 } 1505 ld = _gvn.transform(ld); 1506 if (((bt == T_OBJECT) && C->do_escape_analysis()) || C->eliminate_boxing()) { 1507 // Improve graph before escape analysis and boxing elimination. 1508 record_for_igvn(ld); 1509 } 1510 return ld; 1511 } 1512 1513 Node* GraphKit::store_to_memory(Node* ctl, Node* adr, Node *val, BasicType bt, 1514 int adr_idx, 1515 MemNode::MemOrd mo, 1516 bool require_atomic_access, 1517 bool unaligned, 1518 bool mismatched) { 1519 assert(adr_idx != Compile::AliasIdxTop, "use other store_to_memory factory" ); 1520 const TypePtr* adr_type = NULL; 1521 debug_only(adr_type = C->get_adr_type(adr_idx)); 1522 Node *mem = memory(adr_idx); 1523 Node* st; 1524 if (require_atomic_access && bt == T_LONG) { 1525 st = StoreLNode::make_atomic(ctl, mem, adr, adr_type, val, mo); 1526 } else if (require_atomic_access && bt == T_DOUBLE) { 1527 st = StoreDNode::make_atomic(ctl, mem, adr, adr_type, val, mo); 1528 } else { 1529 st = StoreNode::make(_gvn, ctl, mem, adr, adr_type, val, bt, mo); 1530 } 1531 if (unaligned) { 1532 st->as_Store()->set_unaligned_access(); 1533 } 1534 if (mismatched) { 1535 st->as_Store()->set_mismatched_access(); 1536 } 1537 st = _gvn.transform(st); 1538 set_memory(st, adr_idx); 1539 // Back-to-back stores can only remove intermediate store with DU info 1540 // so push on worklist for optimizer. 1541 if (mem->req() > MemNode::Address && adr == mem->in(MemNode::Address)) 1542 record_for_igvn(st); 1543 1544 return st; 1545 } 1546 1547 Node* GraphKit::access_store_at(Node* ctl, 1548 Node* obj, 1549 Node* adr, 1550 const TypePtr* adr_type, 1551 Node* val, 1552 const Type* val_type, 1553 BasicType bt, 1554 DecoratorSet decorators) { 1555 // Transformation of a value which could be NULL pointer (CastPP #NULL) 1556 // could be delayed during Parse (for example, in adjust_map_after_if()). 1557 // Execute transformation here to avoid barrier generation in such case. 1558 if (_gvn.type(val) == TypePtr::NULL_PTR) { 1559 val = _gvn.makecon(TypePtr::NULL_PTR); 1560 } 1561 1562 set_control(ctl); 1563 if (stopped()) { 1564 return top(); // Dead path ? 1565 } 1566 1567 assert(val != NULL, "not dead path"); 1568 1569 C2AccessValuePtr addr(adr, adr_type); 1570 C2AccessValue value(val, val_type); 1571 C2Access access(this, decorators | C2_WRITE_ACCESS, bt, obj, addr); 1572 if (access.is_raw()) { 1573 return _barrier_set->BarrierSetC2::store_at(access, value); 1574 } else { 1575 return _barrier_set->store_at(access, value); 1576 } 1577 } 1578 1579 Node* GraphKit::access_load_at(Node* obj, // containing obj 1580 Node* adr, // actual adress to store val at 1581 const TypePtr* adr_type, 1582 const Type* val_type, 1583 BasicType bt, 1584 DecoratorSet decorators) { 1585 if (stopped()) { 1586 return top(); // Dead path ? 1587 } 1588 1589 C2AccessValuePtr addr(adr, adr_type); 1590 C2Access access(this, decorators | C2_READ_ACCESS, bt, obj, addr); 1591 if (access.is_raw()) { 1592 return _barrier_set->BarrierSetC2::load_at(access, val_type); 1593 } else { 1594 return _barrier_set->load_at(access, val_type); 1595 } 1596 } 1597 1598 Node* GraphKit::access_atomic_cmpxchg_val_at(Node* ctl, 1599 Node* obj, 1600 Node* adr, 1601 const TypePtr* adr_type, 1602 int alias_idx, 1603 Node* expected_val, 1604 Node* new_val, 1605 const Type* value_type, 1606 BasicType bt, 1607 DecoratorSet decorators) { 1608 set_control(ctl); 1609 C2AccessValuePtr addr(adr, adr_type); 1610 C2AtomicAccess access(this, decorators | C2_READ_ACCESS | C2_WRITE_ACCESS, 1611 bt, obj, addr, alias_idx); 1612 if (access.is_raw()) { 1613 return _barrier_set->BarrierSetC2::atomic_cmpxchg_val_at(access, expected_val, new_val, value_type); 1614 } else { 1615 return _barrier_set->atomic_cmpxchg_val_at(access, expected_val, new_val, value_type); 1616 } 1617 } 1618 1619 Node* GraphKit::access_atomic_cmpxchg_bool_at(Node* ctl, 1620 Node* obj, 1621 Node* adr, 1622 const TypePtr* adr_type, 1623 int alias_idx, 1624 Node* expected_val, 1625 Node* new_val, 1626 const Type* value_type, 1627 BasicType bt, 1628 DecoratorSet decorators) { 1629 set_control(ctl); 1630 C2AccessValuePtr addr(adr, adr_type); 1631 C2AtomicAccess access(this, decorators | C2_READ_ACCESS | C2_WRITE_ACCESS, 1632 bt, obj, addr, alias_idx); 1633 if (access.is_raw()) { 1634 return _barrier_set->BarrierSetC2::atomic_cmpxchg_bool_at(access, expected_val, new_val, value_type); 1635 } else { 1636 return _barrier_set->atomic_cmpxchg_bool_at(access, expected_val, new_val, value_type); 1637 } 1638 } 1639 1640 Node* GraphKit::access_atomic_xchg_at(Node* ctl, 1641 Node* obj, 1642 Node* adr, 1643 const TypePtr* adr_type, 1644 int alias_idx, 1645 Node* new_val, 1646 const Type* value_type, 1647 BasicType bt, 1648 DecoratorSet decorators) { 1649 set_control(ctl); 1650 C2AccessValuePtr addr(adr, adr_type); 1651 C2AtomicAccess access(this, decorators | C2_READ_ACCESS | C2_WRITE_ACCESS, 1652 bt, obj, addr, alias_idx); 1653 if (access.is_raw()) { 1654 return _barrier_set->BarrierSetC2::atomic_xchg_at(access, new_val, value_type); 1655 } else { 1656 return _barrier_set->atomic_xchg_at(access, new_val, value_type); 1657 } 1658 } 1659 1660 Node* GraphKit::access_atomic_add_at(Node* ctl, 1661 Node* obj, 1662 Node* adr, 1663 const TypePtr* adr_type, 1664 int alias_idx, 1665 Node* new_val, 1666 const Type* value_type, 1667 BasicType bt, 1668 DecoratorSet decorators) { 1669 set_control(ctl); 1670 C2AccessValuePtr addr(adr, adr_type); 1671 C2AtomicAccess access(this, decorators | C2_READ_ACCESS | C2_WRITE_ACCESS, bt, obj, addr, alias_idx); 1672 if (access.is_raw()) { 1673 return _barrier_set->BarrierSetC2::atomic_add_at(access, new_val, value_type); 1674 } else { 1675 return _barrier_set->atomic_add_at(access, new_val, value_type); 1676 } 1677 } 1678 1679 void GraphKit::access_clone(Node* ctl, Node* src, Node* dst, Node* size, bool is_array) { 1680 set_control(ctl); 1681 return _barrier_set->clone(this, src, dst, size, is_array); 1682 } 1683 1684 //-------------------------array_element_address------------------------- 1685 Node* GraphKit::array_element_address(Node* ary, Node* idx, BasicType elembt, 1686 const TypeInt* sizetype, Node* ctrl) { 1687 uint shift = exact_log2(type2aelembytes(elembt)); 1688 uint header = arrayOopDesc::base_offset_in_bytes(elembt); 1689 1690 // short-circuit a common case (saves lots of confusing waste motion) 1691 jint idx_con = find_int_con(idx, -1); 1692 if (idx_con >= 0) { 1693 intptr_t offset = header + ((intptr_t)idx_con << shift); 1694 return basic_plus_adr(ary, offset); 1695 } 1696 1697 // must be correct type for alignment purposes 1698 Node* base = basic_plus_adr(ary, header); 1699 idx = Compile::conv_I2X_index(&_gvn, idx, sizetype, ctrl); 1700 Node* scale = _gvn.transform( new LShiftXNode(idx, intcon(shift)) ); 1701 return basic_plus_adr(ary, base, scale); 1702 } 1703 1704 //-------------------------load_array_element------------------------- 1705 Node* GraphKit::load_array_element(Node* ctl, Node* ary, Node* idx, const TypeAryPtr* arytype) { 1706 const Type* elemtype = arytype->elem(); 1707 BasicType elembt = elemtype->array_element_basic_type(); 1708 Node* adr = array_element_address(ary, idx, elembt, arytype->size()); 1709 if (elembt == T_NARROWOOP) { 1710 elembt = T_OBJECT; // To satisfy switch in LoadNode::make() 1711 } 1712 Node* ld = make_load(ctl, adr, elemtype, elembt, arytype, MemNode::unordered); 1713 return ld; 1714 } 1715 1716 //-------------------------set_arguments_for_java_call------------------------- 1717 // Arguments (pre-popped from the stack) are taken from the JVMS. 1718 void GraphKit::set_arguments_for_java_call(CallJavaNode* call) { 1719 // Add the call arguments: 1720 uint nargs = call->method()->arg_size(); 1721 for (uint i = 0; i < nargs; i++) { 1722 Node* arg = argument(i); 1723 call->init_req(i + TypeFunc::Parms, arg); 1724 } 1725 } 1726 1727 //---------------------------set_edges_for_java_call--------------------------- 1728 // Connect a newly created call into the current JVMS. 1729 // A return value node (if any) is returned from set_edges_for_java_call. 1730 void GraphKit::set_edges_for_java_call(CallJavaNode* call, bool must_throw, bool separate_io_proj) { 1731 1732 // Add the predefined inputs: 1733 call->init_req( TypeFunc::Control, control() ); 1734 call->init_req( TypeFunc::I_O , i_o() ); 1735 call->init_req( TypeFunc::Memory , reset_memory() ); 1736 call->init_req( TypeFunc::FramePtr, frameptr() ); 1737 call->init_req( TypeFunc::ReturnAdr, top() ); 1738 1739 add_safepoint_edges(call, must_throw); 1740 1741 Node* xcall = _gvn.transform(call); 1742 1743 if (xcall == top()) { 1744 set_control(top()); 1745 return; 1746 } 1747 assert(xcall == call, "call identity is stable"); 1748 1749 // Re-use the current map to produce the result. 1750 1751 set_control(_gvn.transform(new ProjNode(call, TypeFunc::Control))); 1752 set_i_o( _gvn.transform(new ProjNode(call, TypeFunc::I_O , separate_io_proj))); 1753 set_all_memory_call(xcall, separate_io_proj); 1754 1755 //return xcall; // no need, caller already has it 1756 } 1757 1758 Node* GraphKit::set_results_for_java_call(CallJavaNode* call, bool separate_io_proj) { 1759 if (stopped()) return top(); // maybe the call folded up? 1760 1761 // Capture the return value, if any. 1762 Node* ret; 1763 if (call->method() == NULL || 1764 call->method()->return_type()->basic_type() == T_VOID) 1765 ret = top(); 1766 else ret = _gvn.transform(new ProjNode(call, TypeFunc::Parms)); 1767 1768 // Note: Since any out-of-line call can produce an exception, 1769 // we always insert an I_O projection from the call into the result. 1770 1771 make_slow_call_ex(call, env()->Throwable_klass(), separate_io_proj); 1772 1773 if (separate_io_proj) { 1774 // The caller requested separate projections be used by the fall 1775 // through and exceptional paths, so replace the projections for 1776 // the fall through path. 1777 set_i_o(_gvn.transform( new ProjNode(call, TypeFunc::I_O) )); 1778 set_all_memory(_gvn.transform( new ProjNode(call, TypeFunc::Memory) )); 1779 } 1780 return ret; 1781 } 1782 1783 //--------------------set_predefined_input_for_runtime_call-------------------- 1784 // Reading and setting the memory state is way conservative here. 1785 // The real problem is that I am not doing real Type analysis on memory, 1786 // so I cannot distinguish card mark stores from other stores. Across a GC 1787 // point the Store Barrier and the card mark memory has to agree. I cannot 1788 // have a card mark store and its barrier split across the GC point from 1789 // either above or below. Here I get that to happen by reading ALL of memory. 1790 // A better answer would be to separate out card marks from other memory. 1791 // For now, return the input memory state, so that it can be reused 1792 // after the call, if this call has restricted memory effects. 1793 Node* GraphKit::set_predefined_input_for_runtime_call(SafePointNode* call) { 1794 // Set fixed predefined input arguments 1795 Node* memory = reset_memory(); 1796 call->init_req( TypeFunc::Control, control() ); 1797 call->init_req( TypeFunc::I_O, top() ); // does no i/o 1798 call->init_req( TypeFunc::Memory, memory ); // may gc ptrs 1799 call->init_req( TypeFunc::FramePtr, frameptr() ); 1800 call->init_req( TypeFunc::ReturnAdr, top() ); 1801 return memory; 1802 } 1803 1804 //-------------------set_predefined_output_for_runtime_call-------------------- 1805 // Set control and memory (not i_o) from the call. 1806 // If keep_mem is not NULL, use it for the output state, 1807 // except for the RawPtr output of the call, if hook_mem is TypeRawPtr::BOTTOM. 1808 // If hook_mem is NULL, this call produces no memory effects at all. 1809 // If hook_mem is a Java-visible memory slice (such as arraycopy operands), 1810 // then only that memory slice is taken from the call. 1811 // In the last case, we must put an appropriate memory barrier before 1812 // the call, so as to create the correct anti-dependencies on loads 1813 // preceding the call. 1814 void GraphKit::set_predefined_output_for_runtime_call(Node* call, 1815 Node* keep_mem, 1816 const TypePtr* hook_mem) { 1817 // no i/o 1818 set_control(_gvn.transform( new ProjNode(call,TypeFunc::Control) )); 1819 if (keep_mem) { 1820 // First clone the existing memory state 1821 set_all_memory(keep_mem); 1822 if (hook_mem != NULL) { 1823 // Make memory for the call 1824 Node* mem = _gvn.transform( new ProjNode(call, TypeFunc::Memory) ); 1825 // Set the RawPtr memory state only. This covers all the heap top/GC stuff 1826 // We also use hook_mem to extract specific effects from arraycopy stubs. 1827 set_memory(mem, hook_mem); 1828 } 1829 // ...else the call has NO memory effects. 1830 1831 // Make sure the call advertises its memory effects precisely. 1832 // This lets us build accurate anti-dependences in gcm.cpp. 1833 assert(C->alias_type(call->adr_type()) == C->alias_type(hook_mem), 1834 "call node must be constructed correctly"); 1835 } else { 1836 assert(hook_mem == NULL, ""); 1837 // This is not a "slow path" call; all memory comes from the call. 1838 set_all_memory_call(call); 1839 } 1840 } 1841 1842 1843 // Replace the call with the current state of the kit. 1844 void GraphKit::replace_call(CallNode* call, Node* result, bool do_replaced_nodes) { 1845 JVMState* ejvms = NULL; 1846 if (has_exceptions()) { 1847 ejvms = transfer_exceptions_into_jvms(); 1848 } 1849 1850 ReplacedNodes replaced_nodes = map()->replaced_nodes(); 1851 ReplacedNodes replaced_nodes_exception; 1852 Node* ex_ctl = top(); 1853 1854 SafePointNode* final_state = stop(); 1855 1856 // Find all the needed outputs of this call 1857 CallProjections callprojs; 1858 call->extract_projections(&callprojs, true); 1859 1860 Node* init_mem = call->in(TypeFunc::Memory); 1861 Node* final_mem = final_state->in(TypeFunc::Memory); 1862 Node* final_ctl = final_state->in(TypeFunc::Control); 1863 Node* final_io = final_state->in(TypeFunc::I_O); 1864 1865 // Replace all the old call edges with the edges from the inlining result 1866 if (callprojs.fallthrough_catchproj != NULL) { 1867 C->gvn_replace_by(callprojs.fallthrough_catchproj, final_ctl); 1868 } 1869 if (callprojs.fallthrough_memproj != NULL) { 1870 if (final_mem->is_MergeMem()) { 1871 // Parser's exits MergeMem was not transformed but may be optimized 1872 final_mem = _gvn.transform(final_mem); 1873 } 1874 C->gvn_replace_by(callprojs.fallthrough_memproj, final_mem); 1875 } 1876 if (callprojs.fallthrough_ioproj != NULL) { 1877 C->gvn_replace_by(callprojs.fallthrough_ioproj, final_io); 1878 } 1879 1880 // Replace the result with the new result if it exists and is used 1881 if (callprojs.resproj != NULL && result != NULL) { 1882 C->gvn_replace_by(callprojs.resproj, result); 1883 } 1884 1885 if (ejvms == NULL) { 1886 // No exception edges to simply kill off those paths 1887 if (callprojs.catchall_catchproj != NULL) { 1888 C->gvn_replace_by(callprojs.catchall_catchproj, C->top()); 1889 } 1890 if (callprojs.catchall_memproj != NULL) { 1891 C->gvn_replace_by(callprojs.catchall_memproj, C->top()); 1892 } 1893 if (callprojs.catchall_ioproj != NULL) { 1894 C->gvn_replace_by(callprojs.catchall_ioproj, C->top()); 1895 } 1896 // Replace the old exception object with top 1897 if (callprojs.exobj != NULL) { 1898 C->gvn_replace_by(callprojs.exobj, C->top()); 1899 } 1900 } else { 1901 GraphKit ekit(ejvms); 1902 1903 // Load my combined exception state into the kit, with all phis transformed: 1904 SafePointNode* ex_map = ekit.combine_and_pop_all_exception_states(); 1905 replaced_nodes_exception = ex_map->replaced_nodes(); 1906 1907 Node* ex_oop = ekit.use_exception_state(ex_map); 1908 1909 if (callprojs.catchall_catchproj != NULL) { 1910 C->gvn_replace_by(callprojs.catchall_catchproj, ekit.control()); 1911 ex_ctl = ekit.control(); 1912 } 1913 if (callprojs.catchall_memproj != NULL) { 1914 C->gvn_replace_by(callprojs.catchall_memproj, ekit.reset_memory()); 1915 } 1916 if (callprojs.catchall_ioproj != NULL) { 1917 C->gvn_replace_by(callprojs.catchall_ioproj, ekit.i_o()); 1918 } 1919 1920 // Replace the old exception object with the newly created one 1921 if (callprojs.exobj != NULL) { 1922 C->gvn_replace_by(callprojs.exobj, ex_oop); 1923 } 1924 } 1925 1926 // Disconnect the call from the graph 1927 call->disconnect_inputs(NULL, C); 1928 C->gvn_replace_by(call, C->top()); 1929 1930 // Clean up any MergeMems that feed other MergeMems since the 1931 // optimizer doesn't like that. 1932 if (final_mem->is_MergeMem()) { 1933 Node_List wl; 1934 for (SimpleDUIterator i(final_mem); i.has_next(); i.next()) { 1935 Node* m = i.get(); 1936 if (m->is_MergeMem() && !wl.contains(m)) { 1937 wl.push(m); 1938 } 1939 } 1940 while (wl.size() > 0) { 1941 _gvn.transform(wl.pop()); 1942 } 1943 } 1944 1945 if (callprojs.fallthrough_catchproj != NULL && !final_ctl->is_top() && do_replaced_nodes) { 1946 replaced_nodes.apply(C, final_ctl); 1947 } 1948 if (!ex_ctl->is_top() && do_replaced_nodes) { 1949 replaced_nodes_exception.apply(C, ex_ctl); 1950 } 1951 } 1952 1953 1954 //------------------------------increment_counter------------------------------ 1955 // for statistics: increment a VM counter by 1 1956 1957 void GraphKit::increment_counter(address counter_addr) { 1958 Node* adr1 = makecon(TypeRawPtr::make(counter_addr)); 1959 increment_counter(adr1); 1960 } 1961 1962 void GraphKit::increment_counter(Node* counter_addr) { 1963 int adr_type = Compile::AliasIdxRaw; 1964 Node* ctrl = control(); 1965 Node* cnt = make_load(ctrl, counter_addr, TypeInt::INT, T_INT, adr_type, MemNode::unordered); 1966 Node* incr = _gvn.transform(new AddINode(cnt, _gvn.intcon(1))); 1967 store_to_memory(ctrl, counter_addr, incr, T_INT, adr_type, MemNode::unordered); 1968 } 1969 1970 1971 //------------------------------uncommon_trap---------------------------------- 1972 // Bail out to the interpreter in mid-method. Implemented by calling the 1973 // uncommon_trap blob. This helper function inserts a runtime call with the 1974 // right debug info. 1975 void GraphKit::uncommon_trap(int trap_request, 1976 ciKlass* klass, const char* comment, 1977 bool must_throw, 1978 bool keep_exact_action) { 1979 if (failing()) stop(); 1980 if (stopped()) return; // trap reachable? 1981 1982 // Note: If ProfileTraps is true, and if a deopt. actually 1983 // occurs here, the runtime will make sure an MDO exists. There is 1984 // no need to call method()->ensure_method_data() at this point. 1985 1986 // Set the stack pointer to the right value for reexecution: 1987 set_sp(reexecute_sp()); 1988 1989 #ifdef ASSERT 1990 if (!must_throw) { 1991 // Make sure the stack has at least enough depth to execute 1992 // the current bytecode. 1993 int inputs, ignored_depth; 1994 if (compute_stack_effects(inputs, ignored_depth)) { 1995 assert(sp() >= inputs, "must have enough JVMS stack to execute %s: sp=%d, inputs=%d", 1996 Bytecodes::name(java_bc()), sp(), inputs); 1997 } 1998 } 1999 #endif 2000 2001 Deoptimization::DeoptReason reason = Deoptimization::trap_request_reason(trap_request); 2002 Deoptimization::DeoptAction action = Deoptimization::trap_request_action(trap_request); 2003 2004 switch (action) { 2005 case Deoptimization::Action_maybe_recompile: 2006 case Deoptimization::Action_reinterpret: 2007 // Temporary fix for 6529811 to allow virtual calls to be sure they 2008 // get the chance to go from mono->bi->mega 2009 if (!keep_exact_action && 2010 Deoptimization::trap_request_index(trap_request) < 0 && 2011 too_many_recompiles(reason)) { 2012 // This BCI is causing too many recompilations. 2013 if (C->log() != NULL) { 2014 C->log()->elem("observe that='trap_action_change' reason='%s' from='%s' to='none'", 2015 Deoptimization::trap_reason_name(reason), 2016 Deoptimization::trap_action_name(action)); 2017 } 2018 action = Deoptimization::Action_none; 2019 trap_request = Deoptimization::make_trap_request(reason, action); 2020 } else { 2021 C->set_trap_can_recompile(true); 2022 } 2023 break; 2024 case Deoptimization::Action_make_not_entrant: 2025 C->set_trap_can_recompile(true); 2026 break; 2027 case Deoptimization::Action_none: 2028 case Deoptimization::Action_make_not_compilable: 2029 break; 2030 default: 2031 #ifdef ASSERT 2032 fatal("unknown action %d: %s", action, Deoptimization::trap_action_name(action)); 2033 #endif 2034 break; 2035 } 2036 2037 if (TraceOptoParse) { 2038 char buf[100]; 2039 tty->print_cr("Uncommon trap %s at bci:%d", 2040 Deoptimization::format_trap_request(buf, sizeof(buf), 2041 trap_request), bci()); 2042 } 2043 2044 CompileLog* log = C->log(); 2045 if (log != NULL) { 2046 int kid = (klass == NULL)? -1: log->identify(klass); 2047 log->begin_elem("uncommon_trap bci='%d'", bci()); 2048 char buf[100]; 2049 log->print(" %s", Deoptimization::format_trap_request(buf, sizeof(buf), 2050 trap_request)); 2051 if (kid >= 0) log->print(" klass='%d'", kid); 2052 if (comment != NULL) log->print(" comment='%s'", comment); 2053 log->end_elem(); 2054 } 2055 2056 // Make sure any guarding test views this path as very unlikely 2057 Node *i0 = control()->in(0); 2058 if (i0 != NULL && i0->is_If()) { // Found a guarding if test? 2059 IfNode *iff = i0->as_If(); 2060 float f = iff->_prob; // Get prob 2061 if (control()->Opcode() == Op_IfTrue) { 2062 if (f > PROB_UNLIKELY_MAG(4)) 2063 iff->_prob = PROB_MIN; 2064 } else { 2065 if (f < PROB_LIKELY_MAG(4)) 2066 iff->_prob = PROB_MAX; 2067 } 2068 } 2069 2070 // Clear out dead values from the debug info. 2071 kill_dead_locals(); 2072 2073 // Now insert the uncommon trap subroutine call 2074 address call_addr = SharedRuntime::uncommon_trap_blob()->entry_point(); 2075 const TypePtr* no_memory_effects = NULL; 2076 // Pass the index of the class to be loaded 2077 Node* call = make_runtime_call(RC_NO_LEAF | RC_UNCOMMON | 2078 (must_throw ? RC_MUST_THROW : 0), 2079 OptoRuntime::uncommon_trap_Type(), 2080 call_addr, "uncommon_trap", no_memory_effects, 2081 intcon(trap_request)); 2082 assert(call->as_CallStaticJava()->uncommon_trap_request() == trap_request, 2083 "must extract request correctly from the graph"); 2084 assert(trap_request != 0, "zero value reserved by uncommon_trap_request"); 2085 2086 call->set_req(TypeFunc::ReturnAdr, returnadr()); 2087 // The debug info is the only real input to this call. 2088 2089 // Halt-and-catch fire here. The above call should never return! 2090 HaltNode* halt = new HaltNode(control(), frameptr()); 2091 _gvn.set_type_bottom(halt); 2092 root()->add_req(halt); 2093 2094 stop_and_kill_map(); 2095 } 2096 2097 2098 //--------------------------just_allocated_object------------------------------ 2099 // Report the object that was just allocated. 2100 // It must be the case that there are no intervening safepoints. 2101 // We use this to determine if an object is so "fresh" that 2102 // it does not require card marks. 2103 Node* GraphKit::just_allocated_object(Node* current_control) { 2104 if (C->recent_alloc_ctl() == current_control) 2105 return C->recent_alloc_obj(); 2106 return NULL; 2107 } 2108 2109 2110 void GraphKit::round_double_arguments(ciMethod* dest_method) { 2111 // (Note: TypeFunc::make has a cache that makes this fast.) 2112 const TypeFunc* tf = TypeFunc::make(dest_method); 2113 int nargs = tf->domain()->cnt() - TypeFunc::Parms; 2114 for (int j = 0; j < nargs; j++) { 2115 const Type *targ = tf->domain()->field_at(j + TypeFunc::Parms); 2116 if( targ->basic_type() == T_DOUBLE ) { 2117 // If any parameters are doubles, they must be rounded before 2118 // the call, dstore_rounding does gvn.transform 2119 Node *arg = argument(j); 2120 arg = dstore_rounding(arg); 2121 set_argument(j, arg); 2122 } 2123 } 2124 } 2125 2126 /** 2127 * Record profiling data exact_kls for Node n with the type system so 2128 * that it can propagate it (speculation) 2129 * 2130 * @param n node that the type applies to 2131 * @param exact_kls type from profiling 2132 * @param maybe_null did profiling see null? 2133 * 2134 * @return node with improved type 2135 */ 2136 Node* GraphKit::record_profile_for_speculation(Node* n, ciKlass* exact_kls, ProfilePtrKind ptr_kind) { 2137 const Type* current_type = _gvn.type(n); 2138 assert(UseTypeSpeculation, "type speculation must be on"); 2139 2140 const TypePtr* speculative = current_type->speculative(); 2141 2142 // Should the klass from the profile be recorded in the speculative type? 2143 if (current_type->would_improve_type(exact_kls, jvms()->depth())) { 2144 const TypeKlassPtr* tklass = TypeKlassPtr::make(exact_kls); 2145 const TypeOopPtr* xtype = tklass->as_instance_type(); 2146 assert(xtype->klass_is_exact(), "Should be exact"); 2147 // Any reason to believe n is not null (from this profiling or a previous one)? 2148 assert(ptr_kind != ProfileAlwaysNull, "impossible here"); 2149 const TypePtr* ptr = (ptr_kind == ProfileMaybeNull && current_type->speculative_maybe_null()) ? TypePtr::BOTTOM : TypePtr::NOTNULL; 2150 // record the new speculative type's depth 2151 speculative = xtype->cast_to_ptr_type(ptr->ptr())->is_ptr(); 2152 speculative = speculative->with_inline_depth(jvms()->depth()); 2153 } else if (current_type->would_improve_ptr(ptr_kind)) { 2154 // Profiling report that null was never seen so we can change the 2155 // speculative type to non null ptr. 2156 if (ptr_kind == ProfileAlwaysNull) { 2157 speculative = TypePtr::NULL_PTR; 2158 } else { 2159 assert(ptr_kind == ProfileNeverNull, "nothing else is an improvement"); 2160 const TypePtr* ptr = TypePtr::NOTNULL; 2161 if (speculative != NULL) { 2162 speculative = speculative->cast_to_ptr_type(ptr->ptr())->is_ptr(); 2163 } else { 2164 speculative = ptr; 2165 } 2166 } 2167 } 2168 2169 if (speculative != current_type->speculative()) { 2170 // Build a type with a speculative type (what we think we know 2171 // about the type but will need a guard when we use it) 2172 const TypeOopPtr* spec_type = TypeOopPtr::make(TypePtr::BotPTR, Type::OffsetBot, TypeOopPtr::InstanceBot, speculative); 2173 // We're changing the type, we need a new CheckCast node to carry 2174 // the new type. The new type depends on the control: what 2175 // profiling tells us is only valid from here as far as we can 2176 // tell. 2177 Node* cast = new CheckCastPPNode(control(), n, current_type->remove_speculative()->join_speculative(spec_type)); 2178 cast = _gvn.transform(cast); 2179 replace_in_map(n, cast); 2180 n = cast; 2181 } 2182 2183 return n; 2184 } 2185 2186 /** 2187 * Record profiling data from receiver profiling at an invoke with the 2188 * type system so that it can propagate it (speculation) 2189 * 2190 * @param n receiver node 2191 * 2192 * @return node with improved type 2193 */ 2194 Node* GraphKit::record_profiled_receiver_for_speculation(Node* n) { 2195 if (!UseTypeSpeculation) { 2196 return n; 2197 } 2198 ciKlass* exact_kls = profile_has_unique_klass(); 2199 ProfilePtrKind ptr_kind = ProfileMaybeNull; 2200 if ((java_bc() == Bytecodes::_checkcast || 2201 java_bc() == Bytecodes::_instanceof || 2202 java_bc() == Bytecodes::_aastore) && 2203 method()->method_data()->is_mature()) { 2204 ciProfileData* data = method()->method_data()->bci_to_data(bci()); 2205 if (data != NULL) { 2206 if (!data->as_BitData()->null_seen()) { 2207 ptr_kind = ProfileNeverNull; 2208 } else { 2209 assert(data->is_ReceiverTypeData(), "bad profile data type"); 2210 ciReceiverTypeData* call = (ciReceiverTypeData*)data->as_ReceiverTypeData(); 2211 uint i = 0; 2212 for (; i < call->row_limit(); i++) { 2213 ciKlass* receiver = call->receiver(i); 2214 if (receiver != NULL) { 2215 break; 2216 } 2217 } 2218 ptr_kind = (i == call->row_limit()) ? ProfileAlwaysNull : ProfileMaybeNull; 2219 } 2220 } 2221 } 2222 return record_profile_for_speculation(n, exact_kls, ptr_kind); 2223 } 2224 2225 /** 2226 * Record profiling data from argument profiling at an invoke with the 2227 * type system so that it can propagate it (speculation) 2228 * 2229 * @param dest_method target method for the call 2230 * @param bc what invoke bytecode is this? 2231 */ 2232 void GraphKit::record_profiled_arguments_for_speculation(ciMethod* dest_method, Bytecodes::Code bc) { 2233 if (!UseTypeSpeculation) { 2234 return; 2235 } 2236 const TypeFunc* tf = TypeFunc::make(dest_method); 2237 int nargs = tf->domain()->cnt() - TypeFunc::Parms; 2238 int skip = Bytecodes::has_receiver(bc) ? 1 : 0; 2239 for (int j = skip, i = 0; j < nargs && i < TypeProfileArgsLimit; j++) { 2240 const Type *targ = tf->domain()->field_at(j + TypeFunc::Parms); 2241 if (targ->basic_type() == T_OBJECT || targ->basic_type() == T_ARRAY) { 2242 ProfilePtrKind ptr_kind = ProfileMaybeNull; 2243 ciKlass* better_type = NULL; 2244 if (method()->argument_profiled_type(bci(), i, better_type, ptr_kind)) { 2245 record_profile_for_speculation(argument(j), better_type, ptr_kind); 2246 } 2247 i++; 2248 } 2249 } 2250 } 2251 2252 /** 2253 * Record profiling data from parameter profiling at an invoke with 2254 * the type system so that it can propagate it (speculation) 2255 */ 2256 void GraphKit::record_profiled_parameters_for_speculation() { 2257 if (!UseTypeSpeculation) { 2258 return; 2259 } 2260 for (int i = 0, j = 0; i < method()->arg_size() ; i++) { 2261 if (_gvn.type(local(i))->isa_oopptr()) { 2262 ProfilePtrKind ptr_kind = ProfileMaybeNull; 2263 ciKlass* better_type = NULL; 2264 if (method()->parameter_profiled_type(j, better_type, ptr_kind)) { 2265 record_profile_for_speculation(local(i), better_type, ptr_kind); 2266 } 2267 j++; 2268 } 2269 } 2270 } 2271 2272 /** 2273 * Record profiling data from return value profiling at an invoke with 2274 * the type system so that it can propagate it (speculation) 2275 */ 2276 void GraphKit::record_profiled_return_for_speculation() { 2277 if (!UseTypeSpeculation) { 2278 return; 2279 } 2280 ProfilePtrKind ptr_kind = ProfileMaybeNull; 2281 ciKlass* better_type = NULL; 2282 if (method()->return_profiled_type(bci(), better_type, ptr_kind)) { 2283 // If profiling reports a single type for the return value, 2284 // feed it to the type system so it can propagate it as a 2285 // speculative type 2286 record_profile_for_speculation(stack(sp()-1), better_type, ptr_kind); 2287 } 2288 } 2289 2290 void GraphKit::round_double_result(ciMethod* dest_method) { 2291 // A non-strict method may return a double value which has an extended 2292 // exponent, but this must not be visible in a caller which is 'strict' 2293 // If a strict caller invokes a non-strict callee, round a double result 2294 2295 BasicType result_type = dest_method->return_type()->basic_type(); 2296 assert( method() != NULL, "must have caller context"); 2297 if( result_type == T_DOUBLE && method()->is_strict() && !dest_method->is_strict() ) { 2298 // Destination method's return value is on top of stack 2299 // dstore_rounding() does gvn.transform 2300 Node *result = pop_pair(); 2301 result = dstore_rounding(result); 2302 push_pair(result); 2303 } 2304 } 2305 2306 // rounding for strict float precision conformance 2307 Node* GraphKit::precision_rounding(Node* n) { 2308 return UseStrictFP && _method->flags().is_strict() 2309 && UseSSE == 0 && Matcher::strict_fp_requires_explicit_rounding 2310 ? _gvn.transform( new RoundFloatNode(0, n) ) 2311 : n; 2312 } 2313 2314 // rounding for strict double precision conformance 2315 Node* GraphKit::dprecision_rounding(Node *n) { 2316 return UseStrictFP && _method->flags().is_strict() 2317 && UseSSE <= 1 && Matcher::strict_fp_requires_explicit_rounding 2318 ? _gvn.transform( new RoundDoubleNode(0, n) ) 2319 : n; 2320 } 2321 2322 // rounding for non-strict double stores 2323 Node* GraphKit::dstore_rounding(Node* n) { 2324 return Matcher::strict_fp_requires_explicit_rounding 2325 && UseSSE <= 1 2326 ? _gvn.transform( new RoundDoubleNode(0, n) ) 2327 : n; 2328 } 2329 2330 //============================================================================= 2331 // Generate a fast path/slow path idiom. Graph looks like: 2332 // [foo] indicates that 'foo' is a parameter 2333 // 2334 // [in] NULL 2335 // \ / 2336 // CmpP 2337 // Bool ne 2338 // If 2339 // / \ 2340 // True False-<2> 2341 // / | 2342 // / cast_not_null 2343 // Load | | ^ 2344 // [fast_test] | | 2345 // gvn to opt_test | | 2346 // / \ | <1> 2347 // True False | 2348 // | \\ | 2349 // [slow_call] \[fast_result] 2350 // Ctl Val \ \ 2351 // | \ \ 2352 // Catch <1> \ \ 2353 // / \ ^ \ \ 2354 // Ex No_Ex | \ \ 2355 // | \ \ | \ <2> \ 2356 // ... \ [slow_res] | | \ [null_result] 2357 // \ \--+--+--- | | 2358 // \ | / \ | / 2359 // --------Region Phi 2360 // 2361 //============================================================================= 2362 // Code is structured as a series of driver functions all called 'do_XXX' that 2363 // call a set of helper functions. Helper functions first, then drivers. 2364 2365 //------------------------------null_check_oop--------------------------------- 2366 // Null check oop. Set null-path control into Region in slot 3. 2367 // Make a cast-not-nullness use the other not-null control. Return cast. 2368 Node* GraphKit::null_check_oop(Node* value, Node* *null_control, 2369 bool never_see_null, 2370 bool safe_for_replace, 2371 bool speculative) { 2372 // Initial NULL check taken path 2373 (*null_control) = top(); 2374 Node* cast = null_check_common(value, T_OBJECT, false, null_control, speculative); 2375 2376 // Generate uncommon_trap: 2377 if (never_see_null && (*null_control) != top()) { 2378 // If we see an unexpected null at a check-cast we record it and force a 2379 // recompile; the offending check-cast will be compiled to handle NULLs. 2380 // If we see more than one offending BCI, then all checkcasts in the 2381 // method will be compiled to handle NULLs. 2382 PreserveJVMState pjvms(this); 2383 set_control(*null_control); 2384 replace_in_map(value, null()); 2385 Deoptimization::DeoptReason reason = Deoptimization::reason_null_check(speculative); 2386 uncommon_trap(reason, 2387 Deoptimization::Action_make_not_entrant); 2388 (*null_control) = top(); // NULL path is dead 2389 } 2390 if ((*null_control) == top() && safe_for_replace) { 2391 replace_in_map(value, cast); 2392 } 2393 2394 // Cast away null-ness on the result 2395 return cast; 2396 } 2397 2398 //------------------------------opt_iff---------------------------------------- 2399 // Optimize the fast-check IfNode. Set the fast-path region slot 2. 2400 // Return slow-path control. 2401 Node* GraphKit::opt_iff(Node* region, Node* iff) { 2402 IfNode *opt_iff = _gvn.transform(iff)->as_If(); 2403 2404 // Fast path taken; set region slot 2 2405 Node *fast_taken = _gvn.transform( new IfFalseNode(opt_iff) ); 2406 region->init_req(2,fast_taken); // Capture fast-control 2407 2408 // Fast path not-taken, i.e. slow path 2409 Node *slow_taken = _gvn.transform( new IfTrueNode(opt_iff) ); 2410 return slow_taken; 2411 } 2412 2413 //-----------------------------make_runtime_call------------------------------- 2414 Node* GraphKit::make_runtime_call(int flags, 2415 const TypeFunc* call_type, address call_addr, 2416 const char* call_name, 2417 const TypePtr* adr_type, 2418 // The following parms are all optional. 2419 // The first NULL ends the list. 2420 Node* parm0, Node* parm1, 2421 Node* parm2, Node* parm3, 2422 Node* parm4, Node* parm5, 2423 Node* parm6, Node* parm7) { 2424 // Slow-path call 2425 bool is_leaf = !(flags & RC_NO_LEAF); 2426 bool has_io = (!is_leaf && !(flags & RC_NO_IO)); 2427 if (call_name == NULL) { 2428 assert(!is_leaf, "must supply name for leaf"); 2429 call_name = OptoRuntime::stub_name(call_addr); 2430 } 2431 CallNode* call; 2432 if (!is_leaf) { 2433 call = new CallStaticJavaNode(call_type, call_addr, call_name, 2434 bci(), adr_type); 2435 } else if (flags & RC_NO_FP) { 2436 call = new CallLeafNoFPNode(call_type, call_addr, call_name, adr_type); 2437 } else { 2438 call = new CallLeafNode(call_type, call_addr, call_name, adr_type); 2439 } 2440 2441 // The following is similar to set_edges_for_java_call, 2442 // except that the memory effects of the call are restricted to AliasIdxRaw. 2443 2444 // Slow path call has no side-effects, uses few values 2445 bool wide_in = !(flags & RC_NARROW_MEM); 2446 bool wide_out = (C->get_alias_index(adr_type) == Compile::AliasIdxBot); 2447 2448 Node* prev_mem = NULL; 2449 if (wide_in) { 2450 prev_mem = set_predefined_input_for_runtime_call(call); 2451 } else { 2452 assert(!wide_out, "narrow in => narrow out"); 2453 Node* narrow_mem = memory(adr_type); 2454 prev_mem = reset_memory(); 2455 map()->set_memory(narrow_mem); 2456 set_predefined_input_for_runtime_call(call); 2457 } 2458 2459 // Hook each parm in order. Stop looking at the first NULL. 2460 if (parm0 != NULL) { call->init_req(TypeFunc::Parms+0, parm0); 2461 if (parm1 != NULL) { call->init_req(TypeFunc::Parms+1, parm1); 2462 if (parm2 != NULL) { call->init_req(TypeFunc::Parms+2, parm2); 2463 if (parm3 != NULL) { call->init_req(TypeFunc::Parms+3, parm3); 2464 if (parm4 != NULL) { call->init_req(TypeFunc::Parms+4, parm4); 2465 if (parm5 != NULL) { call->init_req(TypeFunc::Parms+5, parm5); 2466 if (parm6 != NULL) { call->init_req(TypeFunc::Parms+6, parm6); 2467 if (parm7 != NULL) { call->init_req(TypeFunc::Parms+7, parm7); 2468 /* close each nested if ===> */ } } } } } } } } 2469 assert(call->in(call->req()-1) != NULL, "must initialize all parms"); 2470 2471 if (!is_leaf) { 2472 // Non-leaves can block and take safepoints: 2473 add_safepoint_edges(call, ((flags & RC_MUST_THROW) != 0)); 2474 } 2475 // Non-leaves can throw exceptions: 2476 if (has_io) { 2477 call->set_req(TypeFunc::I_O, i_o()); 2478 } 2479 2480 if (flags & RC_UNCOMMON) { 2481 // Set the count to a tiny probability. Cf. Estimate_Block_Frequency. 2482 // (An "if" probability corresponds roughly to an unconditional count. 2483 // Sort of.) 2484 call->set_cnt(PROB_UNLIKELY_MAG(4)); 2485 } 2486 2487 Node* c = _gvn.transform(call); 2488 assert(c == call, "cannot disappear"); 2489 2490 if (wide_out) { 2491 // Slow path call has full side-effects. 2492 set_predefined_output_for_runtime_call(call); 2493 } else { 2494 // Slow path call has few side-effects, and/or sets few values. 2495 set_predefined_output_for_runtime_call(call, prev_mem, adr_type); 2496 } 2497 2498 if (has_io) { 2499 set_i_o(_gvn.transform(new ProjNode(call, TypeFunc::I_O))); 2500 } 2501 return call; 2502 2503 } 2504 2505 //------------------------------merge_memory----------------------------------- 2506 // Merge memory from one path into the current memory state. 2507 void GraphKit::merge_memory(Node* new_mem, Node* region, int new_path) { 2508 for (MergeMemStream mms(merged_memory(), new_mem->as_MergeMem()); mms.next_non_empty2(); ) { 2509 Node* old_slice = mms.force_memory(); 2510 Node* new_slice = mms.memory2(); 2511 if (old_slice != new_slice) { 2512 PhiNode* phi; 2513 if (old_slice->is_Phi() && old_slice->as_Phi()->region() == region) { 2514 if (mms.is_empty()) { 2515 // clone base memory Phi's inputs for this memory slice 2516 assert(old_slice == mms.base_memory(), "sanity"); 2517 phi = PhiNode::make(region, NULL, Type::MEMORY, mms.adr_type(C)); 2518 _gvn.set_type(phi, Type::MEMORY); 2519 for (uint i = 1; i < phi->req(); i++) { 2520 phi->init_req(i, old_slice->in(i)); 2521 } 2522 } else { 2523 phi = old_slice->as_Phi(); // Phi was generated already 2524 } 2525 } else { 2526 phi = PhiNode::make(region, old_slice, Type::MEMORY, mms.adr_type(C)); 2527 _gvn.set_type(phi, Type::MEMORY); 2528 } 2529 phi->set_req(new_path, new_slice); 2530 mms.set_memory(phi); 2531 } 2532 } 2533 } 2534 2535 //------------------------------make_slow_call_ex------------------------------ 2536 // Make the exception handler hookups for the slow call 2537 void GraphKit::make_slow_call_ex(Node* call, ciInstanceKlass* ex_klass, bool separate_io_proj, bool deoptimize) { 2538 if (stopped()) return; 2539 2540 // Make a catch node with just two handlers: fall-through and catch-all 2541 Node* i_o = _gvn.transform( new ProjNode(call, TypeFunc::I_O, separate_io_proj) ); 2542 Node* catc = _gvn.transform( new CatchNode(control(), i_o, 2) ); 2543 Node* norm = _gvn.transform( new CatchProjNode(catc, CatchProjNode::fall_through_index, CatchProjNode::no_handler_bci) ); 2544 Node* excp = _gvn.transform( new CatchProjNode(catc, CatchProjNode::catch_all_index, CatchProjNode::no_handler_bci) ); 2545 2546 { PreserveJVMState pjvms(this); 2547 set_control(excp); 2548 set_i_o(i_o); 2549 2550 if (excp != top()) { 2551 if (deoptimize) { 2552 // Deoptimize if an exception is caught. Don't construct exception state in this case. 2553 uncommon_trap(Deoptimization::Reason_unhandled, 2554 Deoptimization::Action_none); 2555 } else { 2556 // Create an exception state also. 2557 // Use an exact type if the caller has specified a specific exception. 2558 const Type* ex_type = TypeOopPtr::make_from_klass_unique(ex_klass)->cast_to_ptr_type(TypePtr::NotNull); 2559 Node* ex_oop = new CreateExNode(ex_type, control(), i_o); 2560 add_exception_state(make_exception_state(_gvn.transform(ex_oop))); 2561 } 2562 } 2563 } 2564 2565 // Get the no-exception control from the CatchNode. 2566 set_control(norm); 2567 } 2568 2569 static IfNode* gen_subtype_check_compare(Node* ctrl, Node* in1, Node* in2, BoolTest::mask test, float p, PhaseGVN* gvn, BasicType bt) { 2570 Node* cmp = NULL; 2571 switch(bt) { 2572 case T_INT: cmp = new CmpINode(in1, in2); break; 2573 case T_ADDRESS: cmp = new CmpPNode(in1, in2); break; 2574 default: fatal("unexpected comparison type %s", type2name(bt)); 2575 } 2576 gvn->transform(cmp); 2577 Node* bol = gvn->transform(new BoolNode(cmp, test)); 2578 IfNode* iff = new IfNode(ctrl, bol, p, COUNT_UNKNOWN); 2579 gvn->transform(iff); 2580 if (!bol->is_Con()) gvn->record_for_igvn(iff); 2581 return iff; 2582 } 2583 2584 2585 //-------------------------------gen_subtype_check----------------------------- 2586 // Generate a subtyping check. Takes as input the subtype and supertype. 2587 // Returns 2 values: sets the default control() to the true path and returns 2588 // the false path. Only reads invariant memory; sets no (visible) memory. 2589 // The PartialSubtypeCheckNode sets the hidden 1-word cache in the encoding 2590 // but that's not exposed to the optimizer. This call also doesn't take in an 2591 // Object; if you wish to check an Object you need to load the Object's class 2592 // prior to coming here. 2593 Node* Phase::gen_subtype_check(Node* subklass, Node* superklass, Node** ctrl, MergeMemNode* mem, PhaseGVN* gvn) { 2594 Compile* C = gvn->C; 2595 2596 if ((*ctrl)->is_top()) { 2597 return C->top(); 2598 } 2599 2600 // Fast check for identical types, perhaps identical constants. 2601 // The types can even be identical non-constants, in cases 2602 // involving Array.newInstance, Object.clone, etc. 2603 if (subklass == superklass) 2604 return C->top(); // false path is dead; no test needed. 2605 2606 if (gvn->type(superklass)->singleton()) { 2607 ciKlass* superk = gvn->type(superklass)->is_klassptr()->klass(); 2608 ciKlass* subk = gvn->type(subklass)->is_klassptr()->klass(); 2609 2610 // In the common case of an exact superklass, try to fold up the 2611 // test before generating code. You may ask, why not just generate 2612 // the code and then let it fold up? The answer is that the generated 2613 // code will necessarily include null checks, which do not always 2614 // completely fold away. If they are also needless, then they turn 2615 // into a performance loss. Example: 2616 // Foo[] fa = blah(); Foo x = fa[0]; fa[1] = x; 2617 // Here, the type of 'fa' is often exact, so the store check 2618 // of fa[1]=x will fold up, without testing the nullness of x. 2619 switch (C->static_subtype_check(superk, subk)) { 2620 case Compile::SSC_always_false: 2621 { 2622 Node* always_fail = *ctrl; 2623 *ctrl = gvn->C->top(); 2624 return always_fail; 2625 } 2626 case Compile::SSC_always_true: 2627 return C->top(); 2628 case Compile::SSC_easy_test: 2629 { 2630 // Just do a direct pointer compare and be done. 2631 IfNode* iff = gen_subtype_check_compare(*ctrl, subklass, superklass, BoolTest::eq, PROB_STATIC_FREQUENT, gvn, T_ADDRESS); 2632 *ctrl = gvn->transform(new IfTrueNode(iff)); 2633 return gvn->transform(new IfFalseNode(iff)); 2634 } 2635 case Compile::SSC_full_test: 2636 break; 2637 default: 2638 ShouldNotReachHere(); 2639 } 2640 } 2641 2642 // %%% Possible further optimization: Even if the superklass is not exact, 2643 // if the subklass is the unique subtype of the superklass, the check 2644 // will always succeed. We could leave a dependency behind to ensure this. 2645 2646 // First load the super-klass's check-offset 2647 Node *p1 = gvn->transform(new AddPNode(superklass, superklass, gvn->MakeConX(in_bytes(Klass::super_check_offset_offset())))); 2648 Node* m = mem->memory_at(C->get_alias_index(gvn->type(p1)->is_ptr())); 2649 Node *chk_off = gvn->transform(new LoadINode(NULL, m, p1, gvn->type(p1)->is_ptr(), TypeInt::INT, MemNode::unordered)); 2650 int cacheoff_con = in_bytes(Klass::secondary_super_cache_offset()); 2651 bool might_be_cache = (gvn->find_int_con(chk_off, cacheoff_con) == cacheoff_con); 2652 2653 // Load from the sub-klass's super-class display list, or a 1-word cache of 2654 // the secondary superclass list, or a failing value with a sentinel offset 2655 // if the super-klass is an interface or exceptionally deep in the Java 2656 // hierarchy and we have to scan the secondary superclass list the hard way. 2657 // Worst-case type is a little odd: NULL is allowed as a result (usually 2658 // klass loads can never produce a NULL). 2659 Node *chk_off_X = chk_off; 2660 #ifdef _LP64 2661 chk_off_X = gvn->transform(new ConvI2LNode(chk_off_X)); 2662 #endif 2663 Node *p2 = gvn->transform(new AddPNode(subklass,subklass,chk_off_X)); 2664 // For some types like interfaces the following loadKlass is from a 1-word 2665 // cache which is mutable so can't use immutable memory. Other 2666 // types load from the super-class display table which is immutable. 2667 m = mem->memory_at(C->get_alias_index(gvn->type(p2)->is_ptr())); 2668 Node *kmem = might_be_cache ? m : C->immutable_memory(); 2669 Node *nkls = gvn->transform(LoadKlassNode::make(*gvn, NULL, kmem, p2, gvn->type(p2)->is_ptr(), TypeKlassPtr::OBJECT_OR_NULL)); 2670 2671 // Compile speed common case: ARE a subtype and we canNOT fail 2672 if( superklass == nkls ) 2673 return C->top(); // false path is dead; no test needed. 2674 2675 // See if we get an immediate positive hit. Happens roughly 83% of the 2676 // time. Test to see if the value loaded just previously from the subklass 2677 // is exactly the superklass. 2678 IfNode *iff1 = gen_subtype_check_compare(*ctrl, superklass, nkls, BoolTest::eq, PROB_LIKELY(0.83f), gvn, T_ADDRESS); 2679 Node *iftrue1 = gvn->transform( new IfTrueNode (iff1)); 2680 *ctrl = gvn->transform(new IfFalseNode(iff1)); 2681 2682 // Compile speed common case: Check for being deterministic right now. If 2683 // chk_off is a constant and not equal to cacheoff then we are NOT a 2684 // subklass. In this case we need exactly the 1 test above and we can 2685 // return those results immediately. 2686 if (!might_be_cache) { 2687 Node* not_subtype_ctrl = *ctrl; 2688 *ctrl = iftrue1; // We need exactly the 1 test above 2689 return not_subtype_ctrl; 2690 } 2691 2692 // Gather the various success & failures here 2693 RegionNode *r_ok_subtype = new RegionNode(4); 2694 gvn->record_for_igvn(r_ok_subtype); 2695 RegionNode *r_not_subtype = new RegionNode(3); 2696 gvn->record_for_igvn(r_not_subtype); 2697 2698 r_ok_subtype->init_req(1, iftrue1); 2699 2700 // Check for immediate negative hit. Happens roughly 11% of the time (which 2701 // is roughly 63% of the remaining cases). Test to see if the loaded 2702 // check-offset points into the subklass display list or the 1-element 2703 // cache. If it points to the display (and NOT the cache) and the display 2704 // missed then it's not a subtype. 2705 Node *cacheoff = gvn->intcon(cacheoff_con); 2706 IfNode *iff2 = gen_subtype_check_compare(*ctrl, chk_off, cacheoff, BoolTest::ne, PROB_LIKELY(0.63f), gvn, T_INT); 2707 r_not_subtype->init_req(1, gvn->transform(new IfTrueNode (iff2))); 2708 *ctrl = gvn->transform(new IfFalseNode(iff2)); 2709 2710 // Check for self. Very rare to get here, but it is taken 1/3 the time. 2711 // No performance impact (too rare) but allows sharing of secondary arrays 2712 // which has some footprint reduction. 2713 IfNode *iff3 = gen_subtype_check_compare(*ctrl, subklass, superklass, BoolTest::eq, PROB_LIKELY(0.36f), gvn, T_ADDRESS); 2714 r_ok_subtype->init_req(2, gvn->transform(new IfTrueNode(iff3))); 2715 *ctrl = gvn->transform(new IfFalseNode(iff3)); 2716 2717 // -- Roads not taken here: -- 2718 // We could also have chosen to perform the self-check at the beginning 2719 // of this code sequence, as the assembler does. This would not pay off 2720 // the same way, since the optimizer, unlike the assembler, can perform 2721 // static type analysis to fold away many successful self-checks. 2722 // Non-foldable self checks work better here in second position, because 2723 // the initial primary superclass check subsumes a self-check for most 2724 // types. An exception would be a secondary type like array-of-interface, 2725 // which does not appear in its own primary supertype display. 2726 // Finally, we could have chosen to move the self-check into the 2727 // PartialSubtypeCheckNode, and from there out-of-line in a platform 2728 // dependent manner. But it is worthwhile to have the check here, 2729 // where it can be perhaps be optimized. The cost in code space is 2730 // small (register compare, branch). 2731 2732 // Now do a linear scan of the secondary super-klass array. Again, no real 2733 // performance impact (too rare) but it's gotta be done. 2734 // Since the code is rarely used, there is no penalty for moving it 2735 // out of line, and it can only improve I-cache density. 2736 // The decision to inline or out-of-line this final check is platform 2737 // dependent, and is found in the AD file definition of PartialSubtypeCheck. 2738 Node* psc = gvn->transform( 2739 new PartialSubtypeCheckNode(*ctrl, subklass, superklass)); 2740 2741 IfNode *iff4 = gen_subtype_check_compare(*ctrl, psc, gvn->zerocon(T_OBJECT), BoolTest::ne, PROB_FAIR, gvn, T_ADDRESS); 2742 r_not_subtype->init_req(2, gvn->transform(new IfTrueNode (iff4))); 2743 r_ok_subtype ->init_req(3, gvn->transform(new IfFalseNode(iff4))); 2744 2745 // Return false path; set default control to true path. 2746 *ctrl = gvn->transform(r_ok_subtype); 2747 return gvn->transform(r_not_subtype); 2748 } 2749 2750 // Profile-driven exact type check: 2751 Node* GraphKit::type_check_receiver(Node* receiver, ciKlass* klass, 2752 float prob, 2753 Node* *casted_receiver) { 2754 const TypeKlassPtr* tklass = TypeKlassPtr::make(klass); 2755 Node* recv_klass = load_object_klass(receiver); 2756 Node* want_klass = makecon(tklass); 2757 Node* cmp = _gvn.transform( new CmpPNode(recv_klass, want_klass) ); 2758 Node* bol = _gvn.transform( new BoolNode(cmp, BoolTest::eq) ); 2759 IfNode* iff = create_and_xform_if(control(), bol, prob, COUNT_UNKNOWN); 2760 set_control( _gvn.transform( new IfTrueNode (iff) )); 2761 Node* fail = _gvn.transform( new IfFalseNode(iff) ); 2762 2763 const TypeOopPtr* recv_xtype = tklass->as_instance_type(); 2764 assert(recv_xtype->klass_is_exact(), ""); 2765 2766 // Subsume downstream occurrences of receiver with a cast to 2767 // recv_xtype, since now we know what the type will be. 2768 Node* cast = new CheckCastPPNode(control(), receiver, recv_xtype); 2769 (*casted_receiver) = _gvn.transform(cast); 2770 // (User must make the replace_in_map call.) 2771 2772 return fail; 2773 } 2774 2775 2776 //------------------------------seems_never_null------------------------------- 2777 // Use null_seen information if it is available from the profile. 2778 // If we see an unexpected null at a type check we record it and force a 2779 // recompile; the offending check will be recompiled to handle NULLs. 2780 // If we see several offending BCIs, then all checks in the 2781 // method will be recompiled. 2782 bool GraphKit::seems_never_null(Node* obj, ciProfileData* data, bool& speculating) { 2783 speculating = !_gvn.type(obj)->speculative_maybe_null(); 2784 Deoptimization::DeoptReason reason = Deoptimization::reason_null_check(speculating); 2785 if (UncommonNullCast // Cutout for this technique 2786 && obj != null() // And not the -Xcomp stupid case? 2787 && !too_many_traps(reason) 2788 ) { 2789 if (speculating) { 2790 return true; 2791 } 2792 if (data == NULL) 2793 // Edge case: no mature data. Be optimistic here. 2794 return true; 2795 // If the profile has not seen a null, assume it won't happen. 2796 assert(java_bc() == Bytecodes::_checkcast || 2797 java_bc() == Bytecodes::_instanceof || 2798 java_bc() == Bytecodes::_aastore, "MDO must collect null_seen bit here"); 2799 return !data->as_BitData()->null_seen(); 2800 } 2801 speculating = false; 2802 return false; 2803 } 2804 2805 //------------------------maybe_cast_profiled_receiver------------------------- 2806 // If the profile has seen exactly one type, narrow to exactly that type. 2807 // Subsequent type checks will always fold up. 2808 Node* GraphKit::maybe_cast_profiled_receiver(Node* not_null_obj, 2809 ciKlass* require_klass, 2810 ciKlass* spec_klass, 2811 bool safe_for_replace) { 2812 if (!UseTypeProfile || !TypeProfileCasts) return NULL; 2813 2814 Deoptimization::DeoptReason reason = Deoptimization::reason_class_check(spec_klass != NULL); 2815 2816 // Make sure we haven't already deoptimized from this tactic. 2817 if (too_many_traps(reason) || too_many_recompiles(reason)) 2818 return NULL; 2819 2820 // (No, this isn't a call, but it's enough like a virtual call 2821 // to use the same ciMethod accessor to get the profile info...) 2822 // If we have a speculative type use it instead of profiling (which 2823 // may not help us) 2824 ciKlass* exact_kls = spec_klass == NULL ? profile_has_unique_klass() : spec_klass; 2825 if (exact_kls != NULL) {// no cast failures here 2826 if (require_klass == NULL || 2827 C->static_subtype_check(require_klass, exact_kls) == Compile::SSC_always_true) { 2828 // If we narrow the type to match what the type profile sees or 2829 // the speculative type, we can then remove the rest of the 2830 // cast. 2831 // This is a win, even if the exact_kls is very specific, 2832 // because downstream operations, such as method calls, 2833 // will often benefit from the sharper type. 2834 Node* exact_obj = not_null_obj; // will get updated in place... 2835 Node* slow_ctl = type_check_receiver(exact_obj, exact_kls, 1.0, 2836 &exact_obj); 2837 { PreserveJVMState pjvms(this); 2838 set_control(slow_ctl); 2839 uncommon_trap_exact(reason, Deoptimization::Action_maybe_recompile); 2840 } 2841 if (safe_for_replace) { 2842 replace_in_map(not_null_obj, exact_obj); 2843 } 2844 return exact_obj; 2845 } 2846 // assert(ssc == Compile::SSC_always_true)... except maybe the profile lied to us. 2847 } 2848 2849 return NULL; 2850 } 2851 2852 /** 2853 * Cast obj to type and emit guard unless we had too many traps here 2854 * already 2855 * 2856 * @param obj node being casted 2857 * @param type type to cast the node to 2858 * @param not_null true if we know node cannot be null 2859 */ 2860 Node* GraphKit::maybe_cast_profiled_obj(Node* obj, 2861 ciKlass* type, 2862 bool not_null) { 2863 if (stopped()) { 2864 return obj; 2865 } 2866 2867 // type == NULL if profiling tells us this object is always null 2868 if (type != NULL) { 2869 Deoptimization::DeoptReason class_reason = Deoptimization::Reason_speculate_class_check; 2870 Deoptimization::DeoptReason null_reason = Deoptimization::Reason_speculate_null_check; 2871 2872 if (!too_many_traps(null_reason) && !too_many_recompiles(null_reason) && 2873 !too_many_traps(class_reason) && 2874 !too_many_recompiles(class_reason)) { 2875 Node* not_null_obj = NULL; 2876 // not_null is true if we know the object is not null and 2877 // there's no need for a null check 2878 if (!not_null) { 2879 Node* null_ctl = top(); 2880 not_null_obj = null_check_oop(obj, &null_ctl, true, true, true); 2881 assert(null_ctl->is_top(), "no null control here"); 2882 } else { 2883 not_null_obj = obj; 2884 } 2885 2886 Node* exact_obj = not_null_obj; 2887 ciKlass* exact_kls = type; 2888 Node* slow_ctl = type_check_receiver(exact_obj, exact_kls, 1.0, 2889 &exact_obj); 2890 { 2891 PreserveJVMState pjvms(this); 2892 set_control(slow_ctl); 2893 uncommon_trap_exact(class_reason, Deoptimization::Action_maybe_recompile); 2894 } 2895 replace_in_map(not_null_obj, exact_obj); 2896 obj = exact_obj; 2897 } 2898 } else { 2899 if (!too_many_traps(Deoptimization::Reason_null_assert) && 2900 !too_many_recompiles(Deoptimization::Reason_null_assert)) { 2901 Node* exact_obj = null_assert(obj); 2902 replace_in_map(obj, exact_obj); 2903 obj = exact_obj; 2904 } 2905 } 2906 return obj; 2907 } 2908 2909 //-------------------------------gen_instanceof-------------------------------- 2910 // Generate an instance-of idiom. Used by both the instance-of bytecode 2911 // and the reflective instance-of call. 2912 Node* GraphKit::gen_instanceof(Node* obj, Node* superklass, bool safe_for_replace) { 2913 kill_dead_locals(); // Benefit all the uncommon traps 2914 assert( !stopped(), "dead parse path should be checked in callers" ); 2915 assert(!TypePtr::NULL_PTR->higher_equal(_gvn.type(superklass)->is_klassptr()), 2916 "must check for not-null not-dead klass in callers"); 2917 2918 // Make the merge point 2919 enum { _obj_path = 1, _fail_path, _null_path, PATH_LIMIT }; 2920 RegionNode* region = new RegionNode(PATH_LIMIT); 2921 Node* phi = new PhiNode(region, TypeInt::BOOL); 2922 C->set_has_split_ifs(true); // Has chance for split-if optimization 2923 2924 ciProfileData* data = NULL; 2925 if (java_bc() == Bytecodes::_instanceof) { // Only for the bytecode 2926 data = method()->method_data()->bci_to_data(bci()); 2927 } 2928 bool speculative_not_null = false; 2929 bool never_see_null = (ProfileDynamicTypes // aggressive use of profile 2930 && seems_never_null(obj, data, speculative_not_null)); 2931 2932 // Null check; get casted pointer; set region slot 3 2933 Node* null_ctl = top(); 2934 Node* not_null_obj = null_check_oop(obj, &null_ctl, never_see_null, safe_for_replace, speculative_not_null); 2935 2936 // If not_null_obj is dead, only null-path is taken 2937 if (stopped()) { // Doing instance-of on a NULL? 2938 set_control(null_ctl); 2939 return intcon(0); 2940 } 2941 region->init_req(_null_path, null_ctl); 2942 phi ->init_req(_null_path, intcon(0)); // Set null path value 2943 if (null_ctl == top()) { 2944 // Do this eagerly, so that pattern matches like is_diamond_phi 2945 // will work even during parsing. 2946 assert(_null_path == PATH_LIMIT-1, "delete last"); 2947 region->del_req(_null_path); 2948 phi ->del_req(_null_path); 2949 } 2950 2951 // Do we know the type check always succeed? 2952 bool known_statically = false; 2953 if (_gvn.type(superklass)->singleton()) { 2954 ciKlass* superk = _gvn.type(superklass)->is_klassptr()->klass(); 2955 ciKlass* subk = _gvn.type(obj)->is_oopptr()->klass(); 2956 if (subk != NULL && subk->is_loaded()) { 2957 int static_res = C->static_subtype_check(superk, subk); 2958 known_statically = (static_res == Compile::SSC_always_true || static_res == Compile::SSC_always_false); 2959 } 2960 } 2961 2962 if (!known_statically) { 2963 const TypeOopPtr* obj_type = _gvn.type(obj)->is_oopptr(); 2964 // We may not have profiling here or it may not help us. If we 2965 // have a speculative type use it to perform an exact cast. 2966 ciKlass* spec_obj_type = obj_type->speculative_type(); 2967 if (spec_obj_type != NULL || (ProfileDynamicTypes && data != NULL)) { 2968 Node* cast_obj = maybe_cast_profiled_receiver(not_null_obj, NULL, spec_obj_type, safe_for_replace); 2969 if (stopped()) { // Profile disagrees with this path. 2970 set_control(null_ctl); // Null is the only remaining possibility. 2971 return intcon(0); 2972 } 2973 if (cast_obj != NULL) { 2974 not_null_obj = cast_obj; 2975 } 2976 } 2977 } 2978 2979 // Load the object's klass 2980 Node* obj_klass = load_object_klass(not_null_obj); 2981 2982 // Generate the subtype check 2983 Node* not_subtype_ctrl = gen_subtype_check(obj_klass, superklass); 2984 2985 // Plug in the success path to the general merge in slot 1. 2986 region->init_req(_obj_path, control()); 2987 phi ->init_req(_obj_path, intcon(1)); 2988 2989 // Plug in the failing path to the general merge in slot 2. 2990 region->init_req(_fail_path, not_subtype_ctrl); 2991 phi ->init_req(_fail_path, intcon(0)); 2992 2993 // Return final merged results 2994 set_control( _gvn.transform(region) ); 2995 record_for_igvn(region); 2996 2997 // If we know the type check always succeeds then we don't use the 2998 // profiling data at this bytecode. Don't lose it, feed it to the 2999 // type system as a speculative type. 3000 if (safe_for_replace) { 3001 Node* casted_obj = record_profiled_receiver_for_speculation(obj); 3002 replace_in_map(obj, casted_obj); 3003 } 3004 3005 return _gvn.transform(phi); 3006 } 3007 3008 //-------------------------------gen_checkcast--------------------------------- 3009 // Generate a checkcast idiom. Used by both the checkcast bytecode and the 3010 // array store bytecode. Stack must be as-if BEFORE doing the bytecode so the 3011 // uncommon-trap paths work. Adjust stack after this call. 3012 // If failure_control is supplied and not null, it is filled in with 3013 // the control edge for the cast failure. Otherwise, an appropriate 3014 // uncommon trap or exception is thrown. 3015 Node* GraphKit::gen_checkcast(Node *obj, Node* superklass, 3016 Node* *failure_control) { 3017 kill_dead_locals(); // Benefit all the uncommon traps 3018 const TypeKlassPtr *tk = _gvn.type(superklass)->is_klassptr(); 3019 const Type *toop = TypeOopPtr::make_from_klass(tk->klass()); 3020 3021 // Fast cutout: Check the case that the cast is vacuously true. 3022 // This detects the common cases where the test will short-circuit 3023 // away completely. We do this before we perform the null check, 3024 // because if the test is going to turn into zero code, we don't 3025 // want a residual null check left around. (Causes a slowdown, 3026 // for example, in some objArray manipulations, such as a[i]=a[j].) 3027 if (tk->singleton()) { 3028 const TypeOopPtr* objtp = _gvn.type(obj)->isa_oopptr(); 3029 if (objtp != NULL && objtp->klass() != NULL) { 3030 switch (C->static_subtype_check(tk->klass(), objtp->klass())) { 3031 case Compile::SSC_always_true: 3032 // If we know the type check always succeed then we don't use 3033 // the profiling data at this bytecode. Don't lose it, feed it 3034 // to the type system as a speculative type. 3035 return record_profiled_receiver_for_speculation(obj); 3036 case Compile::SSC_always_false: 3037 // It needs a null check because a null will *pass* the cast check. 3038 // A non-null value will always produce an exception. 3039 return null_assert(obj); 3040 } 3041 } 3042 } 3043 3044 ciProfileData* data = NULL; 3045 bool safe_for_replace = false; 3046 if (failure_control == NULL) { // use MDO in regular case only 3047 assert(java_bc() == Bytecodes::_aastore || 3048 java_bc() == Bytecodes::_checkcast, 3049 "interpreter profiles type checks only for these BCs"); 3050 data = method()->method_data()->bci_to_data(bci()); 3051 safe_for_replace = true; 3052 } 3053 3054 // Make the merge point 3055 enum { _obj_path = 1, _null_path, PATH_LIMIT }; 3056 RegionNode* region = new RegionNode(PATH_LIMIT); 3057 Node* phi = new PhiNode(region, toop); 3058 C->set_has_split_ifs(true); // Has chance for split-if optimization 3059 3060 // Use null-cast information if it is available 3061 bool speculative_not_null = false; 3062 bool never_see_null = ((failure_control == NULL) // regular case only 3063 && seems_never_null(obj, data, speculative_not_null)); 3064 3065 // Null check; get casted pointer; set region slot 3 3066 Node* null_ctl = top(); 3067 Node* not_null_obj = null_check_oop(obj, &null_ctl, never_see_null, safe_for_replace, speculative_not_null); 3068 3069 // If not_null_obj is dead, only null-path is taken 3070 if (stopped()) { // Doing instance-of on a NULL? 3071 set_control(null_ctl); 3072 return null(); 3073 } 3074 region->init_req(_null_path, null_ctl); 3075 phi ->init_req(_null_path, null()); // Set null path value 3076 if (null_ctl == top()) { 3077 // Do this eagerly, so that pattern matches like is_diamond_phi 3078 // will work even during parsing. 3079 assert(_null_path == PATH_LIMIT-1, "delete last"); 3080 region->del_req(_null_path); 3081 phi ->del_req(_null_path); 3082 } 3083 3084 Node* cast_obj = NULL; 3085 if (tk->klass_is_exact()) { 3086 // The following optimization tries to statically cast the speculative type of the object 3087 // (for example obtained during profiling) to the type of the superklass and then do a 3088 // dynamic check that the type of the object is what we expect. To work correctly 3089 // for checkcast and aastore the type of superklass should be exact. 3090 const TypeOopPtr* obj_type = _gvn.type(obj)->is_oopptr(); 3091 // We may not have profiling here or it may not help us. If we have 3092 // a speculative type use it to perform an exact cast. 3093 ciKlass* spec_obj_type = obj_type->speculative_type(); 3094 if (spec_obj_type != NULL || data != NULL) { 3095 cast_obj = maybe_cast_profiled_receiver(not_null_obj, tk->klass(), spec_obj_type, safe_for_replace); 3096 if (cast_obj != NULL) { 3097 if (failure_control != NULL) // failure is now impossible 3098 (*failure_control) = top(); 3099 // adjust the type of the phi to the exact klass: 3100 phi->raise_bottom_type(_gvn.type(cast_obj)->meet_speculative(TypePtr::NULL_PTR)); 3101 } 3102 } 3103 } 3104 3105 if (cast_obj == NULL) { 3106 // Load the object's klass 3107 Node* obj_klass = load_object_klass(not_null_obj); 3108 3109 // Generate the subtype check 3110 Node* not_subtype_ctrl = gen_subtype_check( obj_klass, superklass ); 3111 3112 // Plug in success path into the merge 3113 cast_obj = _gvn.transform(new CheckCastPPNode(control(), not_null_obj, toop)); 3114 // Failure path ends in uncommon trap (or may be dead - failure impossible) 3115 if (failure_control == NULL) { 3116 if (not_subtype_ctrl != top()) { // If failure is possible 3117 PreserveJVMState pjvms(this); 3118 set_control(not_subtype_ctrl); 3119 builtin_throw(Deoptimization::Reason_class_check, obj_klass); 3120 } 3121 } else { 3122 (*failure_control) = not_subtype_ctrl; 3123 } 3124 } 3125 3126 region->init_req(_obj_path, control()); 3127 phi ->init_req(_obj_path, cast_obj); 3128 3129 // A merge of NULL or Casted-NotNull obj 3130 Node* res = _gvn.transform(phi); 3131 3132 // Note I do NOT always 'replace_in_map(obj,result)' here. 3133 // if( tk->klass()->can_be_primary_super() ) 3134 // This means that if I successfully store an Object into an array-of-String 3135 // I 'forget' that the Object is really now known to be a String. I have to 3136 // do this because we don't have true union types for interfaces - if I store 3137 // a Baz into an array-of-Interface and then tell the optimizer it's an 3138 // Interface, I forget that it's also a Baz and cannot do Baz-like field 3139 // references to it. FIX THIS WHEN UNION TYPES APPEAR! 3140 // replace_in_map( obj, res ); 3141 3142 // Return final merged results 3143 set_control( _gvn.transform(region) ); 3144 record_for_igvn(region); 3145 3146 return record_profiled_receiver_for_speculation(res); 3147 } 3148 3149 //------------------------------next_monitor----------------------------------- 3150 // What number should be given to the next monitor? 3151 int GraphKit::next_monitor() { 3152 int current = jvms()->monitor_depth()* C->sync_stack_slots(); 3153 int next = current + C->sync_stack_slots(); 3154 // Keep the toplevel high water mark current: 3155 if (C->fixed_slots() < next) C->set_fixed_slots(next); 3156 return current; 3157 } 3158 3159 //------------------------------insert_mem_bar--------------------------------- 3160 // Memory barrier to avoid floating things around 3161 // The membar serves as a pinch point between both control and all memory slices. 3162 Node* GraphKit::insert_mem_bar(int opcode, Node* precedent) { 3163 MemBarNode* mb = MemBarNode::make(C, opcode, Compile::AliasIdxBot, precedent); 3164 mb->init_req(TypeFunc::Control, control()); 3165 mb->init_req(TypeFunc::Memory, reset_memory()); 3166 Node* membar = _gvn.transform(mb); 3167 set_control(_gvn.transform(new ProjNode(membar, TypeFunc::Control))); 3168 set_all_memory_call(membar); 3169 return membar; 3170 } 3171 3172 //-------------------------insert_mem_bar_volatile---------------------------- 3173 // Memory barrier to avoid floating things around 3174 // The membar serves as a pinch point between both control and memory(alias_idx). 3175 // If you want to make a pinch point on all memory slices, do not use this 3176 // function (even with AliasIdxBot); use insert_mem_bar() instead. 3177 Node* GraphKit::insert_mem_bar_volatile(int opcode, int alias_idx, Node* precedent) { 3178 // When Parse::do_put_xxx updates a volatile field, it appends a series 3179 // of MemBarVolatile nodes, one for *each* volatile field alias category. 3180 // The first membar is on the same memory slice as the field store opcode. 3181 // This forces the membar to follow the store. (Bug 6500685 broke this.) 3182 // All the other membars (for other volatile slices, including AliasIdxBot, 3183 // which stands for all unknown volatile slices) are control-dependent 3184 // on the first membar. This prevents later volatile loads or stores 3185 // from sliding up past the just-emitted store. 3186 3187 MemBarNode* mb = MemBarNode::make(C, opcode, alias_idx, precedent); 3188 mb->set_req(TypeFunc::Control,control()); 3189 if (alias_idx == Compile::AliasIdxBot) { 3190 mb->set_req(TypeFunc::Memory, merged_memory()->base_memory()); 3191 } else { 3192 assert(!(opcode == Op_Initialize && alias_idx != Compile::AliasIdxRaw), "fix caller"); 3193 mb->set_req(TypeFunc::Memory, memory(alias_idx)); 3194 } 3195 Node* membar = _gvn.transform(mb); 3196 set_control(_gvn.transform(new ProjNode(membar, TypeFunc::Control))); 3197 if (alias_idx == Compile::AliasIdxBot) { 3198 merged_memory()->set_base_memory(_gvn.transform(new ProjNode(membar, TypeFunc::Memory))); 3199 } else { 3200 set_memory(_gvn.transform(new ProjNode(membar, TypeFunc::Memory)),alias_idx); 3201 } 3202 return membar; 3203 } 3204 3205 //------------------------------shared_lock------------------------------------ 3206 // Emit locking code. 3207 FastLockNode* GraphKit::shared_lock(Node* obj) { 3208 // bci is either a monitorenter bc or InvocationEntryBci 3209 // %%% SynchronizationEntryBCI is redundant; use InvocationEntryBci in interfaces 3210 assert(SynchronizationEntryBCI == InvocationEntryBci, ""); 3211 3212 if( !GenerateSynchronizationCode ) 3213 return NULL; // Not locking things? 3214 if (stopped()) // Dead monitor? 3215 return NULL; 3216 3217 assert(dead_locals_are_killed(), "should kill locals before sync. point"); 3218 3219 // Box the stack location 3220 Node* box = _gvn.transform(new BoxLockNode(next_monitor())); 3221 Node* mem = reset_memory(); 3222 3223 FastLockNode * flock = _gvn.transform(new FastLockNode(0, obj, box) )->as_FastLock(); 3224 if (UseBiasedLocking && PrintPreciseBiasedLockingStatistics) { 3225 // Create the counters for this fast lock. 3226 flock->create_lock_counter(sync_jvms()); // sync_jvms used to get current bci 3227 } 3228 3229 // Create the rtm counters for this fast lock if needed. 3230 flock->create_rtm_lock_counter(sync_jvms()); // sync_jvms used to get current bci 3231 3232 // Add monitor to debug info for the slow path. If we block inside the 3233 // slow path and de-opt, we need the monitor hanging around 3234 map()->push_monitor( flock ); 3235 3236 const TypeFunc *tf = LockNode::lock_type(); 3237 LockNode *lock = new LockNode(C, tf); 3238 3239 lock->init_req( TypeFunc::Control, control() ); 3240 lock->init_req( TypeFunc::Memory , mem ); 3241 lock->init_req( TypeFunc::I_O , top() ) ; // does no i/o 3242 lock->init_req( TypeFunc::FramePtr, frameptr() ); 3243 lock->init_req( TypeFunc::ReturnAdr, top() ); 3244 3245 lock->init_req(TypeFunc::Parms + 0, obj); 3246 lock->init_req(TypeFunc::Parms + 1, box); 3247 lock->init_req(TypeFunc::Parms + 2, flock); 3248 add_safepoint_edges(lock); 3249 3250 lock = _gvn.transform( lock )->as_Lock(); 3251 3252 // lock has no side-effects, sets few values 3253 set_predefined_output_for_runtime_call(lock, mem, TypeRawPtr::BOTTOM); 3254 3255 insert_mem_bar(Op_MemBarAcquireLock); 3256 3257 // Add this to the worklist so that the lock can be eliminated 3258 record_for_igvn(lock); 3259 3260 #ifndef PRODUCT 3261 if (PrintLockStatistics) { 3262 // Update the counter for this lock. Don't bother using an atomic 3263 // operation since we don't require absolute accuracy. 3264 lock->create_lock_counter(map()->jvms()); 3265 increment_counter(lock->counter()->addr()); 3266 } 3267 #endif 3268 3269 return flock; 3270 } 3271 3272 3273 //------------------------------shared_unlock---------------------------------- 3274 // Emit unlocking code. 3275 void GraphKit::shared_unlock(Node* box, Node* obj) { 3276 // bci is either a monitorenter bc or InvocationEntryBci 3277 // %%% SynchronizationEntryBCI is redundant; use InvocationEntryBci in interfaces 3278 assert(SynchronizationEntryBCI == InvocationEntryBci, ""); 3279 3280 if( !GenerateSynchronizationCode ) 3281 return; 3282 if (stopped()) { // Dead monitor? 3283 map()->pop_monitor(); // Kill monitor from debug info 3284 return; 3285 } 3286 3287 // Memory barrier to avoid floating things down past the locked region 3288 insert_mem_bar(Op_MemBarReleaseLock); 3289 3290 const TypeFunc *tf = OptoRuntime::complete_monitor_exit_Type(); 3291 UnlockNode *unlock = new UnlockNode(C, tf); 3292 #ifdef ASSERT 3293 unlock->set_dbg_jvms(sync_jvms()); 3294 #endif 3295 uint raw_idx = Compile::AliasIdxRaw; 3296 unlock->init_req( TypeFunc::Control, control() ); 3297 unlock->init_req( TypeFunc::Memory , memory(raw_idx) ); 3298 unlock->init_req( TypeFunc::I_O , top() ) ; // does no i/o 3299 unlock->init_req( TypeFunc::FramePtr, frameptr() ); 3300 unlock->init_req( TypeFunc::ReturnAdr, top() ); 3301 3302 unlock->init_req(TypeFunc::Parms + 0, obj); 3303 unlock->init_req(TypeFunc::Parms + 1, box); 3304 unlock = _gvn.transform(unlock)->as_Unlock(); 3305 3306 Node* mem = reset_memory(); 3307 3308 // unlock has no side-effects, sets few values 3309 set_predefined_output_for_runtime_call(unlock, mem, TypeRawPtr::BOTTOM); 3310 3311 // Kill monitor from debug info 3312 map()->pop_monitor( ); 3313 } 3314 3315 //-------------------------------get_layout_helper----------------------------- 3316 // If the given klass is a constant or known to be an array, 3317 // fetch the constant layout helper value into constant_value 3318 // and return (Node*)NULL. Otherwise, load the non-constant 3319 // layout helper value, and return the node which represents it. 3320 // This two-faced routine is useful because allocation sites 3321 // almost always feature constant types. 3322 Node* GraphKit::get_layout_helper(Node* klass_node, jint& constant_value) { 3323 const TypeKlassPtr* inst_klass = _gvn.type(klass_node)->isa_klassptr(); 3324 if (!StressReflectiveCode && inst_klass != NULL) { 3325 ciKlass* klass = inst_klass->klass(); 3326 bool xklass = inst_klass->klass_is_exact(); 3327 if (xklass || klass->is_array_klass()) { 3328 jint lhelper = klass->layout_helper(); 3329 if (lhelper != Klass::_lh_neutral_value) { 3330 constant_value = lhelper; 3331 return (Node*) NULL; 3332 } 3333 } 3334 } 3335 constant_value = Klass::_lh_neutral_value; // put in a known value 3336 Node* lhp = basic_plus_adr(klass_node, klass_node, in_bytes(Klass::layout_helper_offset())); 3337 return make_load(NULL, lhp, TypeInt::INT, T_INT, MemNode::unordered); 3338 } 3339 3340 // We just put in an allocate/initialize with a big raw-memory effect. 3341 // Hook selected additional alias categories on the initialization. 3342 static void hook_memory_on_init(GraphKit& kit, int alias_idx, 3343 MergeMemNode* init_in_merge, 3344 Node* init_out_raw) { 3345 DEBUG_ONLY(Node* init_in_raw = init_in_merge->base_memory()); 3346 assert(init_in_merge->memory_at(alias_idx) == init_in_raw, ""); 3347 3348 Node* prevmem = kit.memory(alias_idx); 3349 init_in_merge->set_memory_at(alias_idx, prevmem); 3350 kit.set_memory(init_out_raw, alias_idx); 3351 } 3352 3353 //---------------------------set_output_for_allocation------------------------- 3354 Node* GraphKit::set_output_for_allocation(AllocateNode* alloc, 3355 const TypeOopPtr* oop_type, 3356 bool deoptimize_on_exception) { 3357 int rawidx = Compile::AliasIdxRaw; 3358 alloc->set_req( TypeFunc::FramePtr, frameptr() ); 3359 add_safepoint_edges(alloc); 3360 Node* allocx = _gvn.transform(alloc); 3361 set_control( _gvn.transform(new ProjNode(allocx, TypeFunc::Control) ) ); 3362 // create memory projection for i_o 3363 set_memory ( _gvn.transform( new ProjNode(allocx, TypeFunc::Memory, true) ), rawidx ); 3364 make_slow_call_ex(allocx, env()->Throwable_klass(), true, deoptimize_on_exception); 3365 3366 // create a memory projection as for the normal control path 3367 Node* malloc = _gvn.transform(new ProjNode(allocx, TypeFunc::Memory)); 3368 set_memory(malloc, rawidx); 3369 3370 // a normal slow-call doesn't change i_o, but an allocation does 3371 // we create a separate i_o projection for the normal control path 3372 set_i_o(_gvn.transform( new ProjNode(allocx, TypeFunc::I_O, false) ) ); 3373 Node* rawoop = _gvn.transform( new ProjNode(allocx, TypeFunc::Parms) ); 3374 3375 // put in an initialization barrier 3376 InitializeNode* init = insert_mem_bar_volatile(Op_Initialize, rawidx, 3377 rawoop)->as_Initialize(); 3378 assert(alloc->initialization() == init, "2-way macro link must work"); 3379 assert(init ->allocation() == alloc, "2-way macro link must work"); 3380 { 3381 // Extract memory strands which may participate in the new object's 3382 // initialization, and source them from the new InitializeNode. 3383 // This will allow us to observe initializations when they occur, 3384 // and link them properly (as a group) to the InitializeNode. 3385 assert(init->in(InitializeNode::Memory) == malloc, ""); 3386 MergeMemNode* minit_in = MergeMemNode::make(malloc); 3387 init->set_req(InitializeNode::Memory, minit_in); 3388 record_for_igvn(minit_in); // fold it up later, if possible 3389 Node* minit_out = memory(rawidx); 3390 assert(minit_out->is_Proj() && minit_out->in(0) == init, ""); 3391 if (oop_type->isa_aryptr()) { 3392 const TypePtr* telemref = oop_type->add_offset(Type::OffsetBot); 3393 int elemidx = C->get_alias_index(telemref); 3394 hook_memory_on_init(*this, elemidx, minit_in, minit_out); 3395 } else if (oop_type->isa_instptr()) { 3396 ciInstanceKlass* ik = oop_type->klass()->as_instance_klass(); 3397 for (int i = 0, len = ik->nof_nonstatic_fields(); i < len; i++) { 3398 ciField* field = ik->nonstatic_field_at(i); 3399 if (field->offset() >= TrackedInitializationLimit * HeapWordSize) 3400 continue; // do not bother to track really large numbers of fields 3401 // Find (or create) the alias category for this field: 3402 int fieldidx = C->alias_type(field)->index(); 3403 hook_memory_on_init(*this, fieldidx, minit_in, minit_out); 3404 } 3405 } 3406 } 3407 3408 // Cast raw oop to the real thing... 3409 Node* javaoop = new CheckCastPPNode(control(), rawoop, oop_type); 3410 javaoop = _gvn.transform(javaoop); 3411 C->set_recent_alloc(control(), javaoop); 3412 assert(just_allocated_object(control()) == javaoop, "just allocated"); 3413 3414 #ifdef ASSERT 3415 { // Verify that the AllocateNode::Ideal_allocation recognizers work: 3416 assert(AllocateNode::Ideal_allocation(rawoop, &_gvn) == alloc, 3417 "Ideal_allocation works"); 3418 assert(AllocateNode::Ideal_allocation(javaoop, &_gvn) == alloc, 3419 "Ideal_allocation works"); 3420 if (alloc->is_AllocateArray()) { 3421 assert(AllocateArrayNode::Ideal_array_allocation(rawoop, &_gvn) == alloc->as_AllocateArray(), 3422 "Ideal_allocation works"); 3423 assert(AllocateArrayNode::Ideal_array_allocation(javaoop, &_gvn) == alloc->as_AllocateArray(), 3424 "Ideal_allocation works"); 3425 } else { 3426 assert(alloc->in(AllocateNode::ALength)->is_top(), "no length, please"); 3427 } 3428 } 3429 #endif //ASSERT 3430 3431 return javaoop; 3432 } 3433 3434 //---------------------------new_instance-------------------------------------- 3435 // This routine takes a klass_node which may be constant (for a static type) 3436 // or may be non-constant (for reflective code). It will work equally well 3437 // for either, and the graph will fold nicely if the optimizer later reduces 3438 // the type to a constant. 3439 // The optional arguments are for specialized use by intrinsics: 3440 // - If 'extra_slow_test' if not null is an extra condition for the slow-path. 3441 // - If 'return_size_val', report the the total object size to the caller. 3442 // - deoptimize_on_exception controls how Java exceptions are handled (rethrow vs deoptimize) 3443 Node* GraphKit::new_instance(Node* klass_node, 3444 Node* extra_slow_test, 3445 Node* *return_size_val, 3446 bool deoptimize_on_exception) { 3447 // Compute size in doublewords 3448 // The size is always an integral number of doublewords, represented 3449 // as a positive bytewise size stored in the klass's layout_helper. 3450 // The layout_helper also encodes (in a low bit) the need for a slow path. 3451 jint layout_con = Klass::_lh_neutral_value; 3452 Node* layout_val = get_layout_helper(klass_node, layout_con); 3453 int layout_is_con = (layout_val == NULL); 3454 3455 if (extra_slow_test == NULL) extra_slow_test = intcon(0); 3456 // Generate the initial go-slow test. It's either ALWAYS (return a 3457 // Node for 1) or NEVER (return a NULL) or perhaps (in the reflective 3458 // case) a computed value derived from the layout_helper. 3459 Node* initial_slow_test = NULL; 3460 if (layout_is_con) { 3461 assert(!StressReflectiveCode, "stress mode does not use these paths"); 3462 bool must_go_slow = Klass::layout_helper_needs_slow_path(layout_con); 3463 initial_slow_test = must_go_slow ? intcon(1) : extra_slow_test; 3464 } else { // reflective case 3465 // This reflective path is used by Unsafe.allocateInstance. 3466 // (It may be stress-tested by specifying StressReflectiveCode.) 3467 // Basically, we want to get into the VM is there's an illegal argument. 3468 Node* bit = intcon(Klass::_lh_instance_slow_path_bit); 3469 initial_slow_test = _gvn.transform( new AndINode(layout_val, bit) ); 3470 if (extra_slow_test != intcon(0)) { 3471 initial_slow_test = _gvn.transform( new OrINode(initial_slow_test, extra_slow_test) ); 3472 } 3473 // (Macro-expander will further convert this to a Bool, if necessary.) 3474 } 3475 3476 // Find the size in bytes. This is easy; it's the layout_helper. 3477 // The size value must be valid even if the slow path is taken. 3478 Node* size = NULL; 3479 if (layout_is_con) { 3480 size = MakeConX(Klass::layout_helper_size_in_bytes(layout_con)); 3481 } else { // reflective case 3482 // This reflective path is used by clone and Unsafe.allocateInstance. 3483 size = ConvI2X(layout_val); 3484 3485 // Clear the low bits to extract layout_helper_size_in_bytes: 3486 assert((int)Klass::_lh_instance_slow_path_bit < BytesPerLong, "clear bit"); 3487 Node* mask = MakeConX(~ (intptr_t)right_n_bits(LogBytesPerLong)); 3488 size = _gvn.transform( new AndXNode(size, mask) ); 3489 } 3490 if (return_size_val != NULL) { 3491 (*return_size_val) = size; 3492 } 3493 3494 // This is a precise notnull oop of the klass. 3495 // (Actually, it need not be precise if this is a reflective allocation.) 3496 // It's what we cast the result to. 3497 const TypeKlassPtr* tklass = _gvn.type(klass_node)->isa_klassptr(); 3498 if (!tklass) tklass = TypeKlassPtr::OBJECT; 3499 const TypeOopPtr* oop_type = tklass->as_instance_type(); 3500 3501 // Now generate allocation code 3502 3503 // The entire memory state is needed for slow path of the allocation 3504 // since GC and deoptimization can happened. 3505 Node *mem = reset_memory(); 3506 set_all_memory(mem); // Create new memory state 3507 3508 AllocateNode* alloc = new AllocateNode(C, AllocateNode::alloc_type(Type::TOP), 3509 control(), mem, i_o(), 3510 size, klass_node, 3511 initial_slow_test); 3512 3513 return set_output_for_allocation(alloc, oop_type, deoptimize_on_exception); 3514 } 3515 3516 //-------------------------------new_array------------------------------------- 3517 // helper for both newarray and anewarray 3518 // The 'length' parameter is (obviously) the length of the array. 3519 // See comments on new_instance for the meaning of the other arguments. 3520 Node* GraphKit::new_array(Node* klass_node, // array klass (maybe variable) 3521 Node* length, // number of array elements 3522 int nargs, // number of arguments to push back for uncommon trap 3523 Node* *return_size_val, 3524 bool deoptimize_on_exception) { 3525 jint layout_con = Klass::_lh_neutral_value; 3526 Node* layout_val = get_layout_helper(klass_node, layout_con); 3527 int layout_is_con = (layout_val == NULL); 3528 3529 if (!layout_is_con && !StressReflectiveCode && 3530 !too_many_traps(Deoptimization::Reason_class_check)) { 3531 // This is a reflective array creation site. 3532 // Optimistically assume that it is a subtype of Object[], 3533 // so that we can fold up all the address arithmetic. 3534 layout_con = Klass::array_layout_helper(T_OBJECT); 3535 Node* cmp_lh = _gvn.transform( new CmpINode(layout_val, intcon(layout_con)) ); 3536 Node* bol_lh = _gvn.transform( new BoolNode(cmp_lh, BoolTest::eq) ); 3537 { BuildCutout unless(this, bol_lh, PROB_MAX); 3538 inc_sp(nargs); 3539 uncommon_trap(Deoptimization::Reason_class_check, 3540 Deoptimization::Action_maybe_recompile); 3541 } 3542 layout_val = NULL; 3543 layout_is_con = true; 3544 } 3545 3546 // Generate the initial go-slow test. Make sure we do not overflow 3547 // if length is huge (near 2Gig) or negative! We do not need 3548 // exact double-words here, just a close approximation of needed 3549 // double-words. We can't add any offset or rounding bits, lest we 3550 // take a size -1 of bytes and make it positive. Use an unsigned 3551 // compare, so negative sizes look hugely positive. 3552 int fast_size_limit = FastAllocateSizeLimit; 3553 if (layout_is_con) { 3554 assert(!StressReflectiveCode, "stress mode does not use these paths"); 3555 // Increase the size limit if we have exact knowledge of array type. 3556 int log2_esize = Klass::layout_helper_log2_element_size(layout_con); 3557 fast_size_limit <<= (LogBytesPerLong - log2_esize); 3558 } 3559 3560 Node* initial_slow_cmp = _gvn.transform( new CmpUNode( length, intcon( fast_size_limit ) ) ); 3561 Node* initial_slow_test = _gvn.transform( new BoolNode( initial_slow_cmp, BoolTest::gt ) ); 3562 3563 // --- Size Computation --- 3564 // array_size = round_to_heap(array_header + (length << elem_shift)); 3565 // where round_to_heap(x) == align_to(x, MinObjAlignmentInBytes) 3566 // and align_to(x, y) == ((x + y-1) & ~(y-1)) 3567 // The rounding mask is strength-reduced, if possible. 3568 int round_mask = MinObjAlignmentInBytes - 1; 3569 Node* header_size = NULL; 3570 int header_size_min = arrayOopDesc::base_offset_in_bytes(T_BYTE); 3571 // (T_BYTE has the weakest alignment and size restrictions...) 3572 if (layout_is_con) { 3573 int hsize = Klass::layout_helper_header_size(layout_con); 3574 int eshift = Klass::layout_helper_log2_element_size(layout_con); 3575 BasicType etype = Klass::layout_helper_element_type(layout_con); 3576 if ((round_mask & ~right_n_bits(eshift)) == 0) 3577 round_mask = 0; // strength-reduce it if it goes away completely 3578 assert((hsize & right_n_bits(eshift)) == 0, "hsize is pre-rounded"); 3579 assert(header_size_min <= hsize, "generic minimum is smallest"); 3580 header_size_min = hsize; 3581 header_size = intcon(hsize + round_mask); 3582 } else { 3583 Node* hss = intcon(Klass::_lh_header_size_shift); 3584 Node* hsm = intcon(Klass::_lh_header_size_mask); 3585 Node* hsize = _gvn.transform( new URShiftINode(layout_val, hss) ); 3586 hsize = _gvn.transform( new AndINode(hsize, hsm) ); 3587 Node* mask = intcon(round_mask); 3588 header_size = _gvn.transform( new AddINode(hsize, mask) ); 3589 } 3590 3591 Node* elem_shift = NULL; 3592 if (layout_is_con) { 3593 int eshift = Klass::layout_helper_log2_element_size(layout_con); 3594 if (eshift != 0) 3595 elem_shift = intcon(eshift); 3596 } else { 3597 // There is no need to mask or shift this value. 3598 // The semantics of LShiftINode include an implicit mask to 0x1F. 3599 assert(Klass::_lh_log2_element_size_shift == 0, "use shift in place"); 3600 elem_shift = layout_val; 3601 } 3602 3603 // Transition to native address size for all offset calculations: 3604 Node* lengthx = ConvI2X(length); 3605 Node* headerx = ConvI2X(header_size); 3606 #ifdef _LP64 3607 { const TypeInt* tilen = _gvn.find_int_type(length); 3608 if (tilen != NULL && tilen->_lo < 0) { 3609 // Add a manual constraint to a positive range. Cf. array_element_address. 3610 jint size_max = fast_size_limit; 3611 if (size_max > tilen->_hi) size_max = tilen->_hi; 3612 const TypeInt* tlcon = TypeInt::make(0, size_max, Type::WidenMin); 3613 3614 // Only do a narrow I2L conversion if the range check passed. 3615 IfNode* iff = new IfNode(control(), initial_slow_test, PROB_MIN, COUNT_UNKNOWN); 3616 _gvn.transform(iff); 3617 RegionNode* region = new RegionNode(3); 3618 _gvn.set_type(region, Type::CONTROL); 3619 lengthx = new PhiNode(region, TypeLong::LONG); 3620 _gvn.set_type(lengthx, TypeLong::LONG); 3621 3622 // Range check passed. Use ConvI2L node with narrow type. 3623 Node* passed = IfFalse(iff); 3624 region->init_req(1, passed); 3625 // Make I2L conversion control dependent to prevent it from 3626 // floating above the range check during loop optimizations. 3627 lengthx->init_req(1, C->constrained_convI2L(&_gvn, length, tlcon, passed)); 3628 3629 // Range check failed. Use ConvI2L with wide type because length may be invalid. 3630 region->init_req(2, IfTrue(iff)); 3631 lengthx->init_req(2, ConvI2X(length)); 3632 3633 set_control(region); 3634 record_for_igvn(region); 3635 record_for_igvn(lengthx); 3636 } 3637 } 3638 #endif 3639 3640 // Combine header size (plus rounding) and body size. Then round down. 3641 // This computation cannot overflow, because it is used only in two 3642 // places, one where the length is sharply limited, and the other 3643 // after a successful allocation. 3644 Node* abody = lengthx; 3645 if (elem_shift != NULL) 3646 abody = _gvn.transform( new LShiftXNode(lengthx, elem_shift) ); 3647 Node* size = _gvn.transform( new AddXNode(headerx, abody) ); 3648 if (round_mask != 0) { 3649 Node* mask = MakeConX(~round_mask); 3650 size = _gvn.transform( new AndXNode(size, mask) ); 3651 } 3652 // else if round_mask == 0, the size computation is self-rounding 3653 3654 if (return_size_val != NULL) { 3655 // This is the size 3656 (*return_size_val) = size; 3657 } 3658 3659 // Now generate allocation code 3660 3661 // The entire memory state is needed for slow path of the allocation 3662 // since GC and deoptimization can happened. 3663 Node *mem = reset_memory(); 3664 set_all_memory(mem); // Create new memory state 3665 3666 if (initial_slow_test->is_Bool()) { 3667 // Hide it behind a CMoveI, or else PhaseIdealLoop::split_up will get sick. 3668 initial_slow_test = initial_slow_test->as_Bool()->as_int_value(&_gvn); 3669 } 3670 3671 // Create the AllocateArrayNode and its result projections 3672 AllocateArrayNode* alloc 3673 = new AllocateArrayNode(C, AllocateArrayNode::alloc_type(TypeInt::INT), 3674 control(), mem, i_o(), 3675 size, klass_node, 3676 initial_slow_test, 3677 length); 3678 3679 // Cast to correct type. Note that the klass_node may be constant or not, 3680 // and in the latter case the actual array type will be inexact also. 3681 // (This happens via a non-constant argument to inline_native_newArray.) 3682 // In any case, the value of klass_node provides the desired array type. 3683 const TypeInt* length_type = _gvn.find_int_type(length); 3684 const TypeOopPtr* ary_type = _gvn.type(klass_node)->is_klassptr()->as_instance_type(); 3685 if (ary_type->isa_aryptr() && length_type != NULL) { 3686 // Try to get a better type than POS for the size 3687 ary_type = ary_type->is_aryptr()->cast_to_size(length_type); 3688 } 3689 3690 Node* javaoop = set_output_for_allocation(alloc, ary_type, deoptimize_on_exception); 3691 3692 // Cast length on remaining path to be as narrow as possible 3693 if (map()->find_edge(length) >= 0) { 3694 Node* ccast = alloc->make_ideal_length(ary_type, &_gvn); 3695 if (ccast != length) { 3696 _gvn.set_type_bottom(ccast); 3697 record_for_igvn(ccast); 3698 replace_in_map(length, ccast); 3699 } 3700 } 3701 3702 return javaoop; 3703 } 3704 3705 // The following "Ideal_foo" functions are placed here because they recognize 3706 // the graph shapes created by the functions immediately above. 3707 3708 //---------------------------Ideal_allocation---------------------------------- 3709 // Given an oop pointer or raw pointer, see if it feeds from an AllocateNode. 3710 AllocateNode* AllocateNode::Ideal_allocation(Node* ptr, PhaseTransform* phase) { 3711 if (ptr == NULL) { // reduce dumb test in callers 3712 return NULL; 3713 } 3714 if (ptr->is_CheckCastPP()) { // strip only one raw-to-oop cast 3715 ptr = ptr->in(1); 3716 if (ptr == NULL) return NULL; 3717 } 3718 // Return NULL for allocations with several casts: 3719 // j.l.reflect.Array.newInstance(jobject, jint) 3720 // Object.clone() 3721 // to keep more precise type from last cast. 3722 if (ptr->is_Proj()) { 3723 Node* allo = ptr->in(0); 3724 if (allo != NULL && allo->is_Allocate()) { 3725 return allo->as_Allocate(); 3726 } 3727 } 3728 // Report failure to match. 3729 return NULL; 3730 } 3731 3732 // Fancy version which also strips off an offset (and reports it to caller). 3733 AllocateNode* AllocateNode::Ideal_allocation(Node* ptr, PhaseTransform* phase, 3734 intptr_t& offset) { 3735 Node* base = AddPNode::Ideal_base_and_offset(ptr, phase, offset); 3736 if (base == NULL) return NULL; 3737 return Ideal_allocation(base, phase); 3738 } 3739 3740 // Trace Initialize <- Proj[Parm] <- Allocate 3741 AllocateNode* InitializeNode::allocation() { 3742 Node* rawoop = in(InitializeNode::RawAddress); 3743 if (rawoop->is_Proj()) { 3744 Node* alloc = rawoop->in(0); 3745 if (alloc->is_Allocate()) { 3746 return alloc->as_Allocate(); 3747 } 3748 } 3749 return NULL; 3750 } 3751 3752 // Trace Allocate -> Proj[Parm] -> Initialize 3753 InitializeNode* AllocateNode::initialization() { 3754 ProjNode* rawoop = proj_out_or_null(AllocateNode::RawAddress); 3755 if (rawoop == NULL) return NULL; 3756 for (DUIterator_Fast imax, i = rawoop->fast_outs(imax); i < imax; i++) { 3757 Node* init = rawoop->fast_out(i); 3758 if (init->is_Initialize()) { 3759 assert(init->as_Initialize()->allocation() == this, "2-way link"); 3760 return init->as_Initialize(); 3761 } 3762 } 3763 return NULL; 3764 } 3765 3766 //----------------------------- loop predicates --------------------------- 3767 3768 //------------------------------add_predicate_impl---------------------------- 3769 void GraphKit::add_predicate_impl(Deoptimization::DeoptReason reason, int nargs) { 3770 // Too many traps seen? 3771 if (too_many_traps(reason)) { 3772 #ifdef ASSERT 3773 if (TraceLoopPredicate) { 3774 int tc = C->trap_count(reason); 3775 tty->print("too many traps=%s tcount=%d in ", 3776 Deoptimization::trap_reason_name(reason), tc); 3777 method()->print(); // which method has too many predicate traps 3778 tty->cr(); 3779 } 3780 #endif 3781 // We cannot afford to take more traps here, 3782 // do not generate predicate. 3783 return; 3784 } 3785 3786 Node *cont = _gvn.intcon(1); 3787 Node* opq = _gvn.transform(new Opaque1Node(C, cont)); 3788 Node *bol = _gvn.transform(new Conv2BNode(opq)); 3789 IfNode* iff = create_and_map_if(control(), bol, PROB_MAX, COUNT_UNKNOWN); 3790 Node* iffalse = _gvn.transform(new IfFalseNode(iff)); 3791 C->add_predicate_opaq(opq); 3792 { 3793 PreserveJVMState pjvms(this); 3794 set_control(iffalse); 3795 inc_sp(nargs); 3796 uncommon_trap(reason, Deoptimization::Action_maybe_recompile); 3797 } 3798 Node* iftrue = _gvn.transform(new IfTrueNode(iff)); 3799 set_control(iftrue); 3800 } 3801 3802 //------------------------------add_predicate--------------------------------- 3803 void GraphKit::add_predicate(int nargs) { 3804 if (UseLoopPredicate) { 3805 add_predicate_impl(Deoptimization::Reason_predicate, nargs); 3806 } 3807 // loop's limit check predicate should be near the loop. 3808 add_predicate_impl(Deoptimization::Reason_loop_limit_check, nargs); 3809 } 3810 3811 void GraphKit::sync_kit(IdealKit& ideal) { 3812 set_all_memory(ideal.merged_memory()); 3813 set_i_o(ideal.i_o()); 3814 set_control(ideal.ctrl()); 3815 } 3816 3817 void GraphKit::final_sync(IdealKit& ideal) { 3818 // Final sync IdealKit and graphKit. 3819 sync_kit(ideal); 3820 } 3821 3822 Node* GraphKit::load_String_length(Node* ctrl, Node* str) { 3823 Node* len = load_array_length(load_String_value(ctrl, str)); 3824 Node* coder = load_String_coder(ctrl, str); 3825 // Divide length by 2 if coder is UTF16 3826 return _gvn.transform(new RShiftINode(len, coder)); 3827 } 3828 3829 Node* GraphKit::load_String_value(Node* ctrl, Node* str) { 3830 int value_offset = java_lang_String::value_offset_in_bytes(); 3831 const TypeInstPtr* string_type = TypeInstPtr::make(TypePtr::NotNull, C->env()->String_klass(), 3832 false, NULL, 0); 3833 const TypePtr* value_field_type = string_type->add_offset(value_offset); 3834 const TypeAryPtr* value_type = TypeAryPtr::make(TypePtr::NotNull, 3835 TypeAry::make(TypeInt::BYTE, TypeInt::POS), 3836 ciTypeArrayKlass::make(T_BYTE), true, 0); 3837 Node* p = basic_plus_adr(str, str, value_offset); 3838 Node* load = access_load_at(str, p, value_field_type, value_type, T_OBJECT, 3839 IN_HEAP | C2_CONTROL_DEPENDENT_LOAD); 3840 // String.value field is known to be @Stable. 3841 if (UseImplicitStableValues) { 3842 load = cast_array_to_stable(load, value_type); 3843 } 3844 return load; 3845 } 3846 3847 Node* GraphKit::load_String_coder(Node* ctrl, Node* str) { 3848 if (!CompactStrings) { 3849 return intcon(java_lang_String::CODER_UTF16); 3850 } 3851 int coder_offset = java_lang_String::coder_offset_in_bytes(); 3852 const TypeInstPtr* string_type = TypeInstPtr::make(TypePtr::NotNull, C->env()->String_klass(), 3853 false, NULL, 0); 3854 const TypePtr* coder_field_type = string_type->add_offset(coder_offset); 3855 int coder_field_idx = C->get_alias_index(coder_field_type); 3856 return make_load(ctrl, basic_plus_adr(str, str, coder_offset), 3857 TypeInt::BYTE, T_BYTE, coder_field_idx, MemNode::unordered); 3858 } 3859 3860 void GraphKit::store_String_value(Node* ctrl, Node* str, Node* value) { 3861 int value_offset = java_lang_String::value_offset_in_bytes(); 3862 const TypeInstPtr* string_type = TypeInstPtr::make(TypePtr::NotNull, C->env()->String_klass(), 3863 false, NULL, 0); 3864 const TypePtr* value_field_type = string_type->add_offset(value_offset); 3865 access_store_at(ctrl, str, basic_plus_adr(str, value_offset), value_field_type, 3866 value, TypeAryPtr::BYTES, T_OBJECT, IN_HEAP); 3867 } 3868 3869 void GraphKit::store_String_coder(Node* ctrl, Node* str, Node* value) { 3870 int coder_offset = java_lang_String::coder_offset_in_bytes(); 3871 const TypeInstPtr* string_type = TypeInstPtr::make(TypePtr::NotNull, C->env()->String_klass(), 3872 false, NULL, 0); 3873 const TypePtr* coder_field_type = string_type->add_offset(coder_offset); 3874 int coder_field_idx = C->get_alias_index(coder_field_type); 3875 store_to_memory(ctrl, basic_plus_adr(str, coder_offset), 3876 value, T_BYTE, coder_field_idx, MemNode::unordered); 3877 } 3878 3879 // Capture src and dst memory state with a MergeMemNode 3880 Node* GraphKit::capture_memory(const TypePtr* src_type, const TypePtr* dst_type) { 3881 if (src_type == dst_type) { 3882 // Types are equal, we don't need a MergeMemNode 3883 return memory(src_type); 3884 } 3885 MergeMemNode* merge = MergeMemNode::make(map()->memory()); 3886 record_for_igvn(merge); // fold it up later, if possible 3887 int src_idx = C->get_alias_index(src_type); 3888 int dst_idx = C->get_alias_index(dst_type); 3889 merge->set_memory_at(src_idx, memory(src_idx)); 3890 merge->set_memory_at(dst_idx, memory(dst_idx)); 3891 return merge; 3892 } 3893 3894 Node* GraphKit::compress_string(Node* src, const TypeAryPtr* src_type, Node* dst, Node* count) { 3895 assert(Matcher::match_rule_supported(Op_StrCompressedCopy), "Intrinsic not supported"); 3896 assert(src_type == TypeAryPtr::BYTES || src_type == TypeAryPtr::CHARS, "invalid source type"); 3897 // If input and output memory types differ, capture both states to preserve 3898 // the dependency between preceding and subsequent loads/stores. 3899 // For example, the following program: 3900 // StoreB 3901 // compress_string 3902 // LoadB 3903 // has this memory graph (use->def): 3904 // LoadB -> compress_string -> CharMem 3905 // ... -> StoreB -> ByteMem 3906 // The intrinsic hides the dependency between LoadB and StoreB, causing 3907 // the load to read from memory not containing the result of the StoreB. 3908 // The correct memory graph should look like this: 3909 // LoadB -> compress_string -> MergeMem(CharMem, StoreB(ByteMem)) 3910 Node* mem = capture_memory(src_type, TypeAryPtr::BYTES); 3911 StrCompressedCopyNode* str = new StrCompressedCopyNode(control(), mem, src, dst, count); 3912 Node* res_mem = _gvn.transform(new SCMemProjNode(str)); 3913 set_memory(res_mem, TypeAryPtr::BYTES); 3914 return str; 3915 } 3916 3917 void GraphKit::inflate_string(Node* src, Node* dst, const TypeAryPtr* dst_type, Node* count) { 3918 assert(Matcher::match_rule_supported(Op_StrInflatedCopy), "Intrinsic not supported"); 3919 assert(dst_type == TypeAryPtr::BYTES || dst_type == TypeAryPtr::CHARS, "invalid dest type"); 3920 // Capture src and dst memory (see comment in 'compress_string'). 3921 Node* mem = capture_memory(TypeAryPtr::BYTES, dst_type); 3922 StrInflatedCopyNode* str = new StrInflatedCopyNode(control(), mem, src, dst, count); 3923 set_memory(_gvn.transform(str), dst_type); 3924 } 3925 3926 void GraphKit::inflate_string_slow(Node* src, Node* dst, Node* start, Node* count) { 3927 /** 3928 * int i_char = start; 3929 * for (int i_byte = 0; i_byte < count; i_byte++) { 3930 * dst[i_char++] = (char)(src[i_byte] & 0xff); 3931 * } 3932 */ 3933 add_predicate(); 3934 RegionNode* head = new RegionNode(3); 3935 head->init_req(1, control()); 3936 gvn().set_type(head, Type::CONTROL); 3937 record_for_igvn(head); 3938 3939 Node* i_byte = new PhiNode(head, TypeInt::INT); 3940 i_byte->init_req(1, intcon(0)); 3941 gvn().set_type(i_byte, TypeInt::INT); 3942 record_for_igvn(i_byte); 3943 3944 Node* i_char = new PhiNode(head, TypeInt::INT); 3945 i_char->init_req(1, start); 3946 gvn().set_type(i_char, TypeInt::INT); 3947 record_for_igvn(i_char); 3948 3949 Node* mem = PhiNode::make(head, memory(TypeAryPtr::BYTES), Type::MEMORY, TypeAryPtr::BYTES); 3950 gvn().set_type(mem, Type::MEMORY); 3951 record_for_igvn(mem); 3952 set_control(head); 3953 set_memory(mem, TypeAryPtr::BYTES); 3954 Node* ch = load_array_element(control(), src, i_byte, TypeAryPtr::BYTES); 3955 Node* st = store_to_memory(control(), array_element_address(dst, i_char, T_BYTE), 3956 AndI(ch, intcon(0xff)), T_CHAR, TypeAryPtr::BYTES, MemNode::unordered, 3957 false, false, true /* mismatched */); 3958 3959 IfNode* iff = create_and_map_if(head, Bool(CmpI(i_byte, count), BoolTest::lt), PROB_FAIR, COUNT_UNKNOWN); 3960 head->init_req(2, IfTrue(iff)); 3961 mem->init_req(2, st); 3962 i_byte->init_req(2, AddI(i_byte, intcon(1))); 3963 i_char->init_req(2, AddI(i_char, intcon(2))); 3964 3965 set_control(IfFalse(iff)); 3966 set_memory(st, TypeAryPtr::BYTES); 3967 } 3968 3969 Node* GraphKit::make_constant_from_field(ciField* field, Node* obj) { 3970 if (!field->is_constant()) { 3971 return NULL; // Field not marked as constant. 3972 } 3973 ciInstance* holder = NULL; 3974 if (!field->is_static()) { 3975 ciObject* const_oop = obj->bottom_type()->is_oopptr()->const_oop(); 3976 if (const_oop != NULL && const_oop->is_instance()) { 3977 holder = const_oop->as_instance(); 3978 } 3979 } 3980 const Type* con_type = Type::make_constant_from_field(field, holder, field->layout_type(), 3981 /*is_unsigned_load=*/false); 3982 if (con_type != NULL) { 3983 return makecon(con_type); 3984 } 3985 return NULL; 3986 } 3987 3988 Node* GraphKit::cast_array_to_stable(Node* ary, const TypeAryPtr* ary_type) { 3989 // Reify the property as a CastPP node in Ideal graph to comply with monotonicity 3990 // assumption of CCP analysis. 3991 return _gvn.transform(new CastPPNode(ary, ary_type->cast_to_stable(true))); 3992 }