1 /* 2 * Copyright (c) 1997, 2011, 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 "classfile/systemDictionary.hpp" 27 #include "code/debugInfoRec.hpp" 28 #include "code/nmethod.hpp" 29 #include "code/pcDesc.hpp" 30 #include "code/scopeDesc.hpp" 31 #include "interpreter/bytecode.hpp" 32 #include "interpreter/interpreter.hpp" 33 #include "interpreter/oopMapCache.hpp" 34 #include "memory/allocation.inline.hpp" 35 #include "memory/oopFactory.hpp" 36 #include "memory/resourceArea.hpp" 37 #include "oops/methodOop.hpp" 38 #include "oops/oop.inline.hpp" 39 #include "prims/jvmtiThreadState.hpp" 40 #include "runtime/biasedLocking.hpp" 41 #include "runtime/compilationPolicy.hpp" 42 #include "runtime/deoptimization.hpp" 43 #include "runtime/interfaceSupport.hpp" 44 #include "runtime/sharedRuntime.hpp" 45 #include "runtime/signature.hpp" 46 #include "runtime/stubRoutines.hpp" 47 #include "runtime/thread.hpp" 48 #include "runtime/vframe.hpp" 49 #include "runtime/vframeArray.hpp" 50 #include "runtime/vframe_hp.hpp" 51 #include "utilities/events.hpp" 52 #include "utilities/xmlstream.hpp" 53 #ifdef TARGET_ARCH_x86 54 # include "vmreg_x86.inline.hpp" 55 #endif 56 #ifdef TARGET_ARCH_sparc 57 # include "vmreg_sparc.inline.hpp" 58 #endif 59 #ifdef TARGET_ARCH_zero 60 # include "vmreg_zero.inline.hpp" 61 #endif 62 #ifdef TARGET_ARCH_arm 63 # include "vmreg_arm.inline.hpp" 64 #endif 65 #ifdef TARGET_ARCH_ppc 66 # include "vmreg_ppc.inline.hpp" 67 #endif 68 #ifdef COMPILER2 69 #ifdef TARGET_ARCH_MODEL_x86_32 70 # include "adfiles/ad_x86_32.hpp" 71 #endif 72 #ifdef TARGET_ARCH_MODEL_x86_64 73 # include "adfiles/ad_x86_64.hpp" 74 #endif 75 #ifdef TARGET_ARCH_MODEL_sparc 76 # include "adfiles/ad_sparc.hpp" 77 #endif 78 #ifdef TARGET_ARCH_MODEL_zero 79 # include "adfiles/ad_zero.hpp" 80 #endif 81 #ifdef TARGET_ARCH_MODEL_arm 82 # include "adfiles/ad_arm.hpp" 83 #endif 84 #ifdef TARGET_ARCH_MODEL_ppc 85 # include "adfiles/ad_ppc.hpp" 86 #endif 87 #endif 88 89 bool DeoptimizationMarker::_is_active = false; 90 91 Deoptimization::UnrollBlock::UnrollBlock(int size_of_deoptimized_frame, 92 int caller_adjustment, 93 int caller_actual_parameters, 94 int number_of_frames, 95 intptr_t* frame_sizes, 96 address* frame_pcs, 97 BasicType return_type) { 98 _size_of_deoptimized_frame = size_of_deoptimized_frame; 99 _caller_adjustment = caller_adjustment; 100 _caller_actual_parameters = caller_actual_parameters; 101 _number_of_frames = number_of_frames; 102 _frame_sizes = frame_sizes; 103 _frame_pcs = frame_pcs; 104 _register_block = NEW_C_HEAP_ARRAY(intptr_t, RegisterMap::reg_count * 2); 105 _return_type = return_type; 106 _initial_fp = 0; 107 // PD (x86 only) 108 _counter_temp = 0; 109 _unpack_kind = 0; 110 _sender_sp_temp = 0; 111 112 _total_frame_sizes = size_of_frames(); 113 } 114 115 116 Deoptimization::UnrollBlock::~UnrollBlock() { 117 FREE_C_HEAP_ARRAY(intptr_t, _frame_sizes); 118 FREE_C_HEAP_ARRAY(intptr_t, _frame_pcs); 119 FREE_C_HEAP_ARRAY(intptr_t, _register_block); 120 } 121 122 123 intptr_t* Deoptimization::UnrollBlock::value_addr_at(int register_number) const { 124 assert(register_number < RegisterMap::reg_count, "checking register number"); 125 return &_register_block[register_number * 2]; 126 } 127 128 129 130 int Deoptimization::UnrollBlock::size_of_frames() const { 131 // Acount first for the adjustment of the initial frame 132 int result = _caller_adjustment; 133 for (int index = 0; index < number_of_frames(); index++) { 134 result += frame_sizes()[index]; 135 } 136 return result; 137 } 138 139 140 void Deoptimization::UnrollBlock::print() { 141 ttyLocker ttyl; 142 tty->print_cr("UnrollBlock"); 143 tty->print_cr(" size_of_deoptimized_frame = %d", _size_of_deoptimized_frame); 144 tty->print( " frame_sizes: "); 145 for (int index = 0; index < number_of_frames(); index++) { 146 tty->print("%d ", frame_sizes()[index]); 147 } 148 tty->cr(); 149 } 150 151 152 // In order to make fetch_unroll_info work properly with escape 153 // analysis, The method was changed from JRT_LEAF to JRT_BLOCK_ENTRY and 154 // ResetNoHandleMark and HandleMark were removed from it. The actual reallocation 155 // of previously eliminated objects occurs in realloc_objects, which is 156 // called from the method fetch_unroll_info_helper below. 157 JRT_BLOCK_ENTRY(Deoptimization::UnrollBlock*, Deoptimization::fetch_unroll_info(JavaThread* thread)) 158 // It is actually ok to allocate handles in a leaf method. It causes no safepoints, 159 // but makes the entry a little slower. There is however a little dance we have to 160 // do in debug mode to get around the NoHandleMark code in the JRT_LEAF macro 161 162 // fetch_unroll_info() is called at the beginning of the deoptimization 163 // handler. Note this fact before we start generating temporary frames 164 // that can confuse an asynchronous stack walker. This counter is 165 // decremented at the end of unpack_frames(). 166 thread->inc_in_deopt_handler(); 167 168 return fetch_unroll_info_helper(thread); 169 JRT_END 170 171 172 // This is factored, since it is both called from a JRT_LEAF (deoptimization) and a JRT_ENTRY (uncommon_trap) 173 Deoptimization::UnrollBlock* Deoptimization::fetch_unroll_info_helper(JavaThread* thread) { 174 175 // Note: there is a safepoint safety issue here. No matter whether we enter 176 // via vanilla deopt or uncommon trap we MUST NOT stop at a safepoint once 177 // the vframeArray is created. 178 // 179 180 // Allocate our special deoptimization ResourceMark 181 DeoptResourceMark* dmark = new DeoptResourceMark(thread); 182 assert(thread->deopt_mark() == NULL, "Pending deopt!"); 183 thread->set_deopt_mark(dmark); 184 185 frame stub_frame = thread->last_frame(); // Makes stack walkable as side effect 186 RegisterMap map(thread, true); 187 RegisterMap dummy_map(thread, false); 188 // Now get the deoptee with a valid map 189 frame deoptee = stub_frame.sender(&map); 190 // Set the deoptee nmethod 191 assert(thread->deopt_nmethod() == NULL, "Pending deopt!"); 192 thread->set_deopt_nmethod(deoptee.cb()->as_nmethod_or_null()); 193 194 if (VerifyStack) { 195 thread->validate_frame_layout(); 196 } 197 198 // Create a growable array of VFrames where each VFrame represents an inlined 199 // Java frame. This storage is allocated with the usual system arena. 200 assert(deoptee.is_compiled_frame(), "Wrong frame type"); 201 GrowableArray<compiledVFrame*>* chunk = new GrowableArray<compiledVFrame*>(10); 202 vframe* vf = vframe::new_vframe(&deoptee, &map, thread); 203 while (!vf->is_top()) { 204 assert(vf->is_compiled_frame(), "Wrong frame type"); 205 chunk->push(compiledVFrame::cast(vf)); 206 vf = vf->sender(); 207 } 208 assert(vf->is_compiled_frame(), "Wrong frame type"); 209 chunk->push(compiledVFrame::cast(vf)); 210 211 #ifdef COMPILER2 212 // Reallocate the non-escaping objects and restore their fields. Then 213 // relock objects if synchronization on them was eliminated. 214 if (DoEscapeAnalysis) { 215 if (EliminateAllocations) { 216 assert (chunk->at(0)->scope() != NULL,"expect only compiled java frames"); 217 GrowableArray<ScopeValue*>* objects = chunk->at(0)->scope()->objects(); 218 219 // The flag return_oop() indicates call sites which return oop 220 // in compiled code. Such sites include java method calls, 221 // runtime calls (for example, used to allocate new objects/arrays 222 // on slow code path) and any other calls generated in compiled code. 223 // It is not guaranteed that we can get such information here only 224 // by analyzing bytecode in deoptimized frames. This is why this flag 225 // is set during method compilation (see Compile::Process_OopMap_Node()). 226 bool save_oop_result = chunk->at(0)->scope()->return_oop(); 227 Handle return_value; 228 if (save_oop_result) { 229 // Reallocation may trigger GC. If deoptimization happened on return from 230 // call which returns oop we need to save it since it is not in oopmap. 231 oop result = deoptee.saved_oop_result(&map); 232 assert(result == NULL || result->is_oop(), "must be oop"); 233 return_value = Handle(thread, result); 234 assert(Universe::heap()->is_in_or_null(result), "must be heap pointer"); 235 if (TraceDeoptimization) { 236 tty->print_cr("SAVED OOP RESULT " INTPTR_FORMAT " in thread " INTPTR_FORMAT, result, thread); 237 } 238 } 239 bool reallocated = false; 240 if (objects != NULL) { 241 JRT_BLOCK 242 reallocated = realloc_objects(thread, &deoptee, objects, THREAD); 243 JRT_END 244 } 245 if (reallocated) { 246 reassign_fields(&deoptee, &map, objects); 247 #ifndef PRODUCT 248 if (TraceDeoptimization) { 249 ttyLocker ttyl; 250 tty->print_cr("REALLOC OBJECTS in thread " INTPTR_FORMAT, thread); 251 print_objects(objects); 252 } 253 #endif 254 } 255 if (save_oop_result) { 256 // Restore result. 257 deoptee.set_saved_oop_result(&map, return_value()); 258 } 259 } 260 if (EliminateLocks) { 261 #ifndef PRODUCT 262 bool first = true; 263 #endif 264 for (int i = 0; i < chunk->length(); i++) { 265 compiledVFrame* cvf = chunk->at(i); 266 assert (cvf->scope() != NULL,"expect only compiled java frames"); 267 GrowableArray<MonitorInfo*>* monitors = cvf->monitors(); 268 if (monitors->is_nonempty()) { 269 relock_objects(monitors, thread); 270 #ifndef PRODUCT 271 if (TraceDeoptimization) { 272 ttyLocker ttyl; 273 for (int j = 0; j < monitors->length(); j++) { 274 MonitorInfo* mi = monitors->at(j); 275 if (mi->eliminated()) { 276 if (first) { 277 first = false; 278 tty->print_cr("RELOCK OBJECTS in thread " INTPTR_FORMAT, thread); 279 } 280 tty->print_cr(" object <" INTPTR_FORMAT "> locked", mi->owner()); 281 } 282 } 283 } 284 #endif 285 } 286 } 287 } 288 } 289 #endif // COMPILER2 290 // Ensure that no safepoint is taken after pointers have been stored 291 // in fields of rematerialized objects. If a safepoint occurs from here on 292 // out the java state residing in the vframeArray will be missed. 293 No_Safepoint_Verifier no_safepoint; 294 295 vframeArray* array = create_vframeArray(thread, deoptee, &map, chunk); 296 297 assert(thread->vframe_array_head() == NULL, "Pending deopt!");; 298 thread->set_vframe_array_head(array); 299 300 // Now that the vframeArray has been created if we have any deferred local writes 301 // added by jvmti then we can free up that structure as the data is now in the 302 // vframeArray 303 304 if (thread->deferred_locals() != NULL) { 305 GrowableArray<jvmtiDeferredLocalVariableSet*>* list = thread->deferred_locals(); 306 int i = 0; 307 do { 308 // Because of inlining we could have multiple vframes for a single frame 309 // and several of the vframes could have deferred writes. Find them all. 310 if (list->at(i)->id() == array->original().id()) { 311 jvmtiDeferredLocalVariableSet* dlv = list->at(i); 312 list->remove_at(i); 313 // individual jvmtiDeferredLocalVariableSet are CHeapObj's 314 delete dlv; 315 } else { 316 i++; 317 } 318 } while ( i < list->length() ); 319 if (list->length() == 0) { 320 thread->set_deferred_locals(NULL); 321 // free the list and elements back to C heap. 322 delete list; 323 } 324 325 } 326 327 #ifndef SHARK 328 // Compute the caller frame based on the sender sp of stub_frame and stored frame sizes info. 329 CodeBlob* cb = stub_frame.cb(); 330 // Verify we have the right vframeArray 331 assert(cb->frame_size() >= 0, "Unexpected frame size"); 332 intptr_t* unpack_sp = stub_frame.sp() + cb->frame_size(); 333 334 // If the deopt call site is a MethodHandle invoke call site we have 335 // to adjust the unpack_sp. 336 nmethod* deoptee_nm = deoptee.cb()->as_nmethod_or_null(); 337 if (deoptee_nm != NULL && deoptee_nm->is_method_handle_return(deoptee.pc())) 338 unpack_sp = deoptee.unextended_sp(); 339 340 #ifdef ASSERT 341 assert(cb->is_deoptimization_stub() || cb->is_uncommon_trap_stub(), "just checking"); 342 Events::log("fetch unroll sp " INTPTR_FORMAT, unpack_sp); 343 #endif 344 #else 345 intptr_t* unpack_sp = stub_frame.sender(&dummy_map).unextended_sp(); 346 #endif // !SHARK 347 348 // This is a guarantee instead of an assert because if vframe doesn't match 349 // we will unpack the wrong deoptimized frame and wind up in strange places 350 // where it will be very difficult to figure out what went wrong. Better 351 // to die an early death here than some very obscure death later when the 352 // trail is cold. 353 // Note: on ia64 this guarantee can be fooled by frames with no memory stack 354 // in that it will fail to detect a problem when there is one. This needs 355 // more work in tiger timeframe. 356 guarantee(array->unextended_sp() == unpack_sp, "vframe_array_head must contain the vframeArray to unpack"); 357 358 int number_of_frames = array->frames(); 359 360 // Compute the vframes' sizes. Note that frame_sizes[] entries are ordered from outermost to innermost 361 // virtual activation, which is the reverse of the elements in the vframes array. 362 intptr_t* frame_sizes = NEW_C_HEAP_ARRAY(intptr_t, number_of_frames); 363 // +1 because we always have an interpreter return address for the final slot. 364 address* frame_pcs = NEW_C_HEAP_ARRAY(address, number_of_frames + 1); 365 int callee_parameters = 0; 366 int callee_locals = 0; 367 int popframe_extra_args = 0; 368 // Create an interpreter return address for the stub to use as its return 369 // address so the skeletal frames are perfectly walkable 370 frame_pcs[number_of_frames] = Interpreter::deopt_entry(vtos, 0); 371 372 // PopFrame requires that the preserved incoming arguments from the recently-popped topmost 373 // activation be put back on the expression stack of the caller for reexecution 374 if (JvmtiExport::can_pop_frame() && thread->popframe_forcing_deopt_reexecution()) { 375 popframe_extra_args = in_words(thread->popframe_preserved_args_size_in_words()); 376 } 377 378 // Find the current pc for sender of the deoptee. Since the sender may have been deoptimized 379 // itself since the deoptee vframeArray was created we must get a fresh value of the pc rather 380 // than simply use array->sender.pc(). This requires us to walk the current set of frames 381 // 382 frame deopt_sender = stub_frame.sender(&dummy_map); // First is the deoptee frame 383 deopt_sender = deopt_sender.sender(&dummy_map); // Now deoptee caller 384 385 // It's possible that the number of paramters at the call site is 386 // different than number of arguments in the callee when method 387 // handles are used. If the caller is interpreted get the real 388 // value so that the proper amount of space can be added to it's 389 // frame. 390 int caller_actual_parameters = callee_parameters; 391 if (deopt_sender.is_interpreted_frame()) { 392 methodHandle method = deopt_sender.interpreter_frame_method(); 393 Bytecode_invoke cur = Bytecode_invoke_check(method, 394 deopt_sender.interpreter_frame_bci()); 395 Symbol* signature = method->constants()->signature_ref_at(cur.index()); 396 ArgumentSizeComputer asc(signature); 397 caller_actual_parameters = asc.size() + (cur.has_receiver() ? 1 : 0); 398 } 399 400 // 401 // frame_sizes/frame_pcs[0] oldest frame (int or c2i) 402 // frame_sizes/frame_pcs[1] next oldest frame (int) 403 // frame_sizes/frame_pcs[n] youngest frame (int) 404 // 405 // Now a pc in frame_pcs is actually the return address to the frame's caller (a frame 406 // owns the space for the return address to it's caller). Confusing ain't it. 407 // 408 // The vframe array can address vframes with indices running from 409 // 0.._frames-1. Index 0 is the youngest frame and _frame - 1 is the oldest (root) frame. 410 // When we create the skeletal frames we need the oldest frame to be in the zero slot 411 // in the frame_sizes/frame_pcs so the assembly code can do a trivial walk. 412 // so things look a little strange in this loop. 413 // 414 for (int index = 0; index < array->frames(); index++ ) { 415 // frame[number_of_frames - 1 ] = on_stack_size(youngest) 416 // frame[number_of_frames - 2 ] = on_stack_size(sender(youngest)) 417 // frame[number_of_frames - 3 ] = on_stack_size(sender(sender(youngest))) 418 int caller_parms = callee_parameters; 419 if (index == array->frames() - 1) { 420 // Use the value from the interpreted caller 421 caller_parms = caller_actual_parameters; 422 } 423 frame_sizes[number_of_frames - 1 - index] = BytesPerWord * array->element(index)->on_stack_size(caller_parms, 424 callee_parameters, 425 callee_locals, 426 index == 0, 427 popframe_extra_args); 428 // This pc doesn't have to be perfect just good enough to identify the frame 429 // as interpreted so the skeleton frame will be walkable 430 // The correct pc will be set when the skeleton frame is completely filled out 431 // The final pc we store in the loop is wrong and will be overwritten below 432 frame_pcs[number_of_frames - 1 - index ] = Interpreter::deopt_entry(vtos, 0) - frame::pc_return_offset; 433 434 callee_parameters = array->element(index)->method()->size_of_parameters(); 435 callee_locals = array->element(index)->method()->max_locals(); 436 popframe_extra_args = 0; 437 } 438 439 // Compute whether the root vframe returns a float or double value. 440 BasicType return_type; 441 { 442 HandleMark hm; 443 methodHandle method(thread, array->element(0)->method()); 444 Bytecode_invoke invoke = Bytecode_invoke_check(method, array->element(0)->bci()); 445 return_type = invoke.is_valid() ? invoke.result_type() : T_ILLEGAL; 446 } 447 448 // Compute information for handling adapters and adjusting the frame size of the caller. 449 int caller_adjustment = 0; 450 451 // Compute the amount the oldest interpreter frame will have to adjust 452 // its caller's stack by. If the caller is a compiled frame then 453 // we pretend that the callee has no parameters so that the 454 // extension counts for the full amount of locals and not just 455 // locals-parms. This is because without a c2i adapter the parm 456 // area as created by the compiled frame will not be usable by 457 // the interpreter. (Depending on the calling convention there 458 // may not even be enough space). 459 460 // QQQ I'd rather see this pushed down into last_frame_adjust 461 // and have it take the sender (aka caller). 462 463 if (deopt_sender.is_compiled_frame()) { 464 caller_adjustment = last_frame_adjust(0, callee_locals); 465 } else if (callee_locals > caller_actual_parameters) { 466 // The caller frame may need extending to accommodate 467 // non-parameter locals of the first unpacked interpreted frame. 468 // Compute that adjustment. 469 caller_adjustment = last_frame_adjust(caller_actual_parameters, callee_locals); 470 } 471 472 // If the sender is deoptimized the we must retrieve the address of the handler 473 // since the frame will "magically" show the original pc before the deopt 474 // and we'd undo the deopt. 475 476 frame_pcs[0] = deopt_sender.raw_pc(); 477 478 #ifndef SHARK 479 assert(CodeCache::find_blob_unsafe(frame_pcs[0]) != NULL, "bad pc"); 480 #endif // SHARK 481 482 UnrollBlock* info = new UnrollBlock(array->frame_size() * BytesPerWord, 483 caller_adjustment * BytesPerWord, 484 caller_actual_parameters, 485 number_of_frames, 486 frame_sizes, 487 frame_pcs, 488 return_type); 489 // On some platforms, we need a way to pass fp to the unpacking code 490 // so the skeletal frames come out correct. 491 info->set_initial_fp((intptr_t) array->sender().fp()); 492 493 if (array->frames() > 1) { 494 if (VerifyStack && TraceDeoptimization) { 495 tty->print_cr("Deoptimizing method containing inlining"); 496 } 497 } 498 499 array->set_unroll_block(info); 500 return info; 501 } 502 503 // Called to cleanup deoptimization data structures in normal case 504 // after unpacking to stack and when stack overflow error occurs 505 void Deoptimization::cleanup_deopt_info(JavaThread *thread, 506 vframeArray *array) { 507 508 // Get array if coming from exception 509 if (array == NULL) { 510 array = thread->vframe_array_head(); 511 } 512 thread->set_vframe_array_head(NULL); 513 514 // Free the previous UnrollBlock 515 vframeArray* old_array = thread->vframe_array_last(); 516 thread->set_vframe_array_last(array); 517 518 if (old_array != NULL) { 519 UnrollBlock* old_info = old_array->unroll_block(); 520 old_array->set_unroll_block(NULL); 521 delete old_info; 522 delete old_array; 523 } 524 525 // Deallocate any resource creating in this routine and any ResourceObjs allocated 526 // inside the vframeArray (StackValueCollections) 527 528 delete thread->deopt_mark(); 529 thread->set_deopt_mark(NULL); 530 thread->set_deopt_nmethod(NULL); 531 532 533 if (JvmtiExport::can_pop_frame()) { 534 #ifndef CC_INTERP 535 // Regardless of whether we entered this routine with the pending 536 // popframe condition bit set, we should always clear it now 537 thread->clear_popframe_condition(); 538 #else 539 // C++ interpeter will clear has_pending_popframe when it enters 540 // with method_resume. For deopt_resume2 we clear it now. 541 if (thread->popframe_forcing_deopt_reexecution()) 542 thread->clear_popframe_condition(); 543 #endif /* CC_INTERP */ 544 } 545 546 // unpack_frames() is called at the end of the deoptimization handler 547 // and (in C2) at the end of the uncommon trap handler. Note this fact 548 // so that an asynchronous stack walker can work again. This counter is 549 // incremented at the beginning of fetch_unroll_info() and (in C2) at 550 // the beginning of uncommon_trap(). 551 thread->dec_in_deopt_handler(); 552 } 553 554 555 // Return BasicType of value being returned 556 JRT_LEAF(BasicType, Deoptimization::unpack_frames(JavaThread* thread, int exec_mode)) 557 558 // We are already active int he special DeoptResourceMark any ResourceObj's we 559 // allocate will be freed at the end of the routine. 560 561 // It is actually ok to allocate handles in a leaf method. It causes no safepoints, 562 // but makes the entry a little slower. There is however a little dance we have to 563 // do in debug mode to get around the NoHandleMark code in the JRT_LEAF macro 564 ResetNoHandleMark rnhm; // No-op in release/product versions 565 HandleMark hm; 566 567 frame stub_frame = thread->last_frame(); 568 569 // Since the frame to unpack is the top frame of this thread, the vframe_array_head 570 // must point to the vframeArray for the unpack frame. 571 vframeArray* array = thread->vframe_array_head(); 572 573 #ifndef PRODUCT 574 if (TraceDeoptimization) { 575 tty->print_cr("DEOPT UNPACKING thread " INTPTR_FORMAT " vframeArray " INTPTR_FORMAT " mode %d", thread, array, exec_mode); 576 } 577 #endif 578 579 UnrollBlock* info = array->unroll_block(); 580 581 // Unpack the interpreter frames and any adapter frame (c2 only) we might create. 582 array->unpack_to_stack(stub_frame, exec_mode, info->caller_actual_parameters()); 583 584 BasicType bt = info->return_type(); 585 586 // If we have an exception pending, claim that the return type is an oop 587 // so the deopt_blob does not overwrite the exception_oop. 588 589 if (exec_mode == Unpack_exception) 590 bt = T_OBJECT; 591 592 // Cleanup thread deopt data 593 cleanup_deopt_info(thread, array); 594 595 #ifndef PRODUCT 596 if (VerifyStack) { 597 ResourceMark res_mark; 598 599 thread->validate_frame_layout(); 600 601 // Verify that the just-unpacked frames match the interpreter's 602 // notions of expression stack and locals 603 vframeArray* cur_array = thread->vframe_array_last(); 604 RegisterMap rm(thread, false); 605 rm.set_include_argument_oops(false); 606 bool is_top_frame = true; 607 int callee_size_of_parameters = 0; 608 int callee_max_locals = 0; 609 for (int i = 0; i < cur_array->frames(); i++) { 610 vframeArrayElement* el = cur_array->element(i); 611 frame* iframe = el->iframe(); 612 guarantee(iframe->is_interpreted_frame(), "Wrong frame type"); 613 614 // Get the oop map for this bci 615 InterpreterOopMap mask; 616 int cur_invoke_parameter_size = 0; 617 bool try_next_mask = false; 618 int next_mask_expression_stack_size = -1; 619 int top_frame_expression_stack_adjustment = 0; 620 methodHandle mh(thread, iframe->interpreter_frame_method()); 621 OopMapCache::compute_one_oop_map(mh, iframe->interpreter_frame_bci(), &mask); 622 BytecodeStream str(mh); 623 str.set_start(iframe->interpreter_frame_bci()); 624 int max_bci = mh->code_size(); 625 // Get to the next bytecode if possible 626 assert(str.bci() < max_bci, "bci in interpreter frame out of bounds"); 627 // Check to see if we can grab the number of outgoing arguments 628 // at an uncommon trap for an invoke (where the compiler 629 // generates debug info before the invoke has executed) 630 Bytecodes::Code cur_code = str.next(); 631 if (cur_code == Bytecodes::_invokevirtual || 632 cur_code == Bytecodes::_invokespecial || 633 cur_code == Bytecodes::_invokestatic || 634 cur_code == Bytecodes::_invokeinterface) { 635 Bytecode_invoke invoke(mh, iframe->interpreter_frame_bci()); 636 Symbol* signature = invoke.signature(); 637 ArgumentSizeComputer asc(signature); 638 cur_invoke_parameter_size = asc.size(); 639 if (cur_code != Bytecodes::_invokestatic) { 640 // Add in receiver 641 ++cur_invoke_parameter_size; 642 } 643 } 644 if (str.bci() < max_bci) { 645 Bytecodes::Code bc = str.next(); 646 if (bc >= 0) { 647 // The interpreter oop map generator reports results before 648 // the current bytecode has executed except in the case of 649 // calls. It seems to be hard to tell whether the compiler 650 // has emitted debug information matching the "state before" 651 // a given bytecode or the state after, so we try both 652 switch (cur_code) { 653 case Bytecodes::_invokevirtual: 654 case Bytecodes::_invokespecial: 655 case Bytecodes::_invokestatic: 656 case Bytecodes::_invokeinterface: 657 case Bytecodes::_athrow: 658 break; 659 default: { 660 InterpreterOopMap next_mask; 661 OopMapCache::compute_one_oop_map(mh, str.bci(), &next_mask); 662 next_mask_expression_stack_size = next_mask.expression_stack_size(); 663 // Need to subtract off the size of the result type of 664 // the bytecode because this is not described in the 665 // debug info but returned to the interpreter in the TOS 666 // caching register 667 BasicType bytecode_result_type = Bytecodes::result_type(cur_code); 668 if (bytecode_result_type != T_ILLEGAL) { 669 top_frame_expression_stack_adjustment = type2size[bytecode_result_type]; 670 } 671 assert(top_frame_expression_stack_adjustment >= 0, ""); 672 try_next_mask = true; 673 break; 674 } 675 } 676 } 677 } 678 679 // Verify stack depth and oops in frame 680 // This assertion may be dependent on the platform we're running on and may need modification (tested on x86 and sparc) 681 if (!( 682 /* SPARC */ 683 (iframe->interpreter_frame_expression_stack_size() == mask.expression_stack_size() + callee_size_of_parameters) || 684 /* x86 */ 685 (iframe->interpreter_frame_expression_stack_size() == mask.expression_stack_size() + callee_max_locals) || 686 (try_next_mask && 687 (iframe->interpreter_frame_expression_stack_size() == (next_mask_expression_stack_size - 688 top_frame_expression_stack_adjustment))) || 689 (is_top_frame && (exec_mode == Unpack_exception) && iframe->interpreter_frame_expression_stack_size() == 0) || 690 (is_top_frame && (exec_mode == Unpack_uncommon_trap || exec_mode == Unpack_reexecute) && 691 (iframe->interpreter_frame_expression_stack_size() == mask.expression_stack_size() + cur_invoke_parameter_size)) 692 )) { 693 ttyLocker ttyl; 694 695 // Print out some information that will help us debug the problem 696 tty->print_cr("Wrong number of expression stack elements during deoptimization"); 697 tty->print_cr(" Error occurred while verifying frame %d (0..%d, 0 is topmost)", i, cur_array->frames() - 1); 698 tty->print_cr(" Fabricated interpreter frame had %d expression stack elements", 699 iframe->interpreter_frame_expression_stack_size()); 700 tty->print_cr(" Interpreter oop map had %d expression stack elements", mask.expression_stack_size()); 701 tty->print_cr(" try_next_mask = %d", try_next_mask); 702 tty->print_cr(" next_mask_expression_stack_size = %d", next_mask_expression_stack_size); 703 tty->print_cr(" callee_size_of_parameters = %d", callee_size_of_parameters); 704 tty->print_cr(" callee_max_locals = %d", callee_max_locals); 705 tty->print_cr(" top_frame_expression_stack_adjustment = %d", top_frame_expression_stack_adjustment); 706 tty->print_cr(" exec_mode = %d", exec_mode); 707 tty->print_cr(" cur_invoke_parameter_size = %d", cur_invoke_parameter_size); 708 tty->print_cr(" Thread = " INTPTR_FORMAT ", thread ID = " UINTX_FORMAT, thread, thread->osthread()->thread_id()); 709 tty->print_cr(" Interpreted frames:"); 710 for (int k = 0; k < cur_array->frames(); k++) { 711 vframeArrayElement* el = cur_array->element(k); 712 tty->print_cr(" %s (bci %d)", el->method()->name_and_sig_as_C_string(), el->bci()); 713 } 714 cur_array->print_on_2(tty); 715 guarantee(false, "wrong number of expression stack elements during deopt"); 716 } 717 VerifyOopClosure verify; 718 iframe->oops_interpreted_do(&verify, &rm, false); 719 callee_size_of_parameters = mh->size_of_parameters(); 720 callee_max_locals = mh->max_locals(); 721 is_top_frame = false; 722 } 723 } 724 #endif /* !PRODUCT */ 725 726 727 return bt; 728 JRT_END 729 730 731 int Deoptimization::deoptimize_dependents() { 732 Threads::deoptimized_wrt_marked_nmethods(); 733 return 0; 734 } 735 736 737 #ifdef COMPILER2 738 bool Deoptimization::realloc_objects(JavaThread* thread, frame* fr, GrowableArray<ScopeValue*>* objects, TRAPS) { 739 Handle pending_exception(thread->pending_exception()); 740 const char* exception_file = thread->exception_file(); 741 int exception_line = thread->exception_line(); 742 thread->clear_pending_exception(); 743 744 for (int i = 0; i < objects->length(); i++) { 745 assert(objects->at(i)->is_object(), "invalid debug information"); 746 ObjectValue* sv = (ObjectValue*) objects->at(i); 747 748 KlassHandle k(((ConstantOopReadValue*) sv->klass())->value()()); 749 oop obj = NULL; 750 751 if (k->oop_is_instance()) { 752 instanceKlass* ik = instanceKlass::cast(k()); 753 obj = ik->allocate_instance(CHECK_(false)); 754 } else if (k->oop_is_typeArray()) { 755 typeArrayKlass* ak = typeArrayKlass::cast(k()); 756 assert(sv->field_size() % type2size[ak->element_type()] == 0, "non-integral array length"); 757 int len = sv->field_size() / type2size[ak->element_type()]; 758 obj = ak->allocate(len, CHECK_(false)); 759 } else if (k->oop_is_objArray()) { 760 objArrayKlass* ak = objArrayKlass::cast(k()); 761 obj = ak->allocate(sv->field_size(), CHECK_(false)); 762 } 763 764 assert(obj != NULL, "allocation failed"); 765 assert(sv->value().is_null(), "redundant reallocation"); 766 sv->set_value(obj); 767 } 768 769 if (pending_exception.not_null()) { 770 thread->set_pending_exception(pending_exception(), exception_file, exception_line); 771 } 772 773 return true; 774 } 775 776 // This assumes that the fields are stored in ObjectValue in the same order 777 // they are yielded by do_nonstatic_fields. 778 class FieldReassigner: public FieldClosure { 779 frame* _fr; 780 RegisterMap* _reg_map; 781 ObjectValue* _sv; 782 instanceKlass* _ik; 783 oop _obj; 784 785 int _i; 786 public: 787 FieldReassigner(frame* fr, RegisterMap* reg_map, ObjectValue* sv, oop obj) : 788 _fr(fr), _reg_map(reg_map), _sv(sv), _obj(obj), _i(0) {} 789 790 int i() const { return _i; } 791 792 793 void do_field(fieldDescriptor* fd) { 794 intptr_t val; 795 StackValue* value = 796 StackValue::create_stack_value(_fr, _reg_map, _sv->field_at(i())); 797 int offset = fd->offset(); 798 switch (fd->field_type()) { 799 case T_OBJECT: case T_ARRAY: 800 assert(value->type() == T_OBJECT, "Agreement."); 801 _obj->obj_field_put(offset, value->get_obj()()); 802 break; 803 804 case T_LONG: case T_DOUBLE: { 805 assert(value->type() == T_INT, "Agreement."); 806 StackValue* low = 807 StackValue::create_stack_value(_fr, _reg_map, _sv->field_at(++_i)); 808 #ifdef _LP64 809 jlong res = (jlong)low->get_int(); 810 #else 811 #ifdef SPARC 812 // For SPARC we have to swap high and low words. 813 jlong res = jlong_from((jint)low->get_int(), (jint)value->get_int()); 814 #else 815 jlong res = jlong_from((jint)value->get_int(), (jint)low->get_int()); 816 #endif //SPARC 817 #endif 818 _obj->long_field_put(offset, res); 819 break; 820 } 821 // Have to cast to INT (32 bits) pointer to avoid little/big-endian problem. 822 case T_INT: case T_FLOAT: // 4 bytes. 823 assert(value->type() == T_INT, "Agreement."); 824 val = value->get_int(); 825 _obj->int_field_put(offset, (jint)*((jint*)&val)); 826 break; 827 828 case T_SHORT: case T_CHAR: // 2 bytes 829 assert(value->type() == T_INT, "Agreement."); 830 val = value->get_int(); 831 _obj->short_field_put(offset, (jshort)*((jint*)&val)); 832 break; 833 834 case T_BOOLEAN: case T_BYTE: // 1 byte 835 assert(value->type() == T_INT, "Agreement."); 836 val = value->get_int(); 837 _obj->bool_field_put(offset, (jboolean)*((jint*)&val)); 838 break; 839 840 default: 841 ShouldNotReachHere(); 842 } 843 _i++; 844 } 845 }; 846 847 // restore elements of an eliminated type array 848 void Deoptimization::reassign_type_array_elements(frame* fr, RegisterMap* reg_map, ObjectValue* sv, typeArrayOop obj, BasicType type) { 849 int index = 0; 850 intptr_t val; 851 852 for (int i = 0; i < sv->field_size(); i++) { 853 StackValue* value = StackValue::create_stack_value(fr, reg_map, sv->field_at(i)); 854 switch(type) { 855 case T_LONG: case T_DOUBLE: { 856 assert(value->type() == T_INT, "Agreement."); 857 StackValue* low = 858 StackValue::create_stack_value(fr, reg_map, sv->field_at(++i)); 859 #ifdef _LP64 860 jlong res = (jlong)low->get_int(); 861 #else 862 #ifdef SPARC 863 // For SPARC we have to swap high and low words. 864 jlong res = jlong_from((jint)low->get_int(), (jint)value->get_int()); 865 #else 866 jlong res = jlong_from((jint)value->get_int(), (jint)low->get_int()); 867 #endif //SPARC 868 #endif 869 obj->long_at_put(index, res); 870 break; 871 } 872 873 // Have to cast to INT (32 bits) pointer to avoid little/big-endian problem. 874 case T_INT: case T_FLOAT: // 4 bytes. 875 assert(value->type() == T_INT, "Agreement."); 876 val = value->get_int(); 877 obj->int_at_put(index, (jint)*((jint*)&val)); 878 break; 879 880 case T_SHORT: case T_CHAR: // 2 bytes 881 assert(value->type() == T_INT, "Agreement."); 882 val = value->get_int(); 883 obj->short_at_put(index, (jshort)*((jint*)&val)); 884 break; 885 886 case T_BOOLEAN: case T_BYTE: // 1 byte 887 assert(value->type() == T_INT, "Agreement."); 888 val = value->get_int(); 889 obj->bool_at_put(index, (jboolean)*((jint*)&val)); 890 break; 891 892 default: 893 ShouldNotReachHere(); 894 } 895 index++; 896 } 897 } 898 899 900 // restore fields of an eliminated object array 901 void Deoptimization::reassign_object_array_elements(frame* fr, RegisterMap* reg_map, ObjectValue* sv, objArrayOop obj) { 902 for (int i = 0; i < sv->field_size(); i++) { 903 StackValue* value = StackValue::create_stack_value(fr, reg_map, sv->field_at(i)); 904 assert(value->type() == T_OBJECT, "object element expected"); 905 obj->obj_at_put(i, value->get_obj()()); 906 } 907 } 908 909 910 // restore fields of all eliminated objects and arrays 911 void Deoptimization::reassign_fields(frame* fr, RegisterMap* reg_map, GrowableArray<ScopeValue*>* objects) { 912 for (int i = 0; i < objects->length(); i++) { 913 ObjectValue* sv = (ObjectValue*) objects->at(i); 914 KlassHandle k(((ConstantOopReadValue*) sv->klass())->value()()); 915 Handle obj = sv->value(); 916 assert(obj.not_null(), "reallocation was missed"); 917 918 if (k->oop_is_instance()) { 919 instanceKlass* ik = instanceKlass::cast(k()); 920 FieldReassigner reassign(fr, reg_map, sv, obj()); 921 ik->do_nonstatic_fields(&reassign); 922 } else if (k->oop_is_typeArray()) { 923 typeArrayKlass* ak = typeArrayKlass::cast(k()); 924 reassign_type_array_elements(fr, reg_map, sv, (typeArrayOop) obj(), ak->element_type()); 925 } else if (k->oop_is_objArray()) { 926 reassign_object_array_elements(fr, reg_map, sv, (objArrayOop) obj()); 927 } 928 } 929 } 930 931 932 // relock objects for which synchronization was eliminated 933 void Deoptimization::relock_objects(GrowableArray<MonitorInfo*>* monitors, JavaThread* thread) { 934 for (int i = 0; i < monitors->length(); i++) { 935 MonitorInfo* mon_info = monitors->at(i); 936 if (mon_info->eliminated()) { 937 assert(mon_info->owner() != NULL, "reallocation was missed"); 938 Handle obj = Handle(mon_info->owner()); 939 markOop mark = obj->mark(); 940 if (UseBiasedLocking && mark->has_bias_pattern()) { 941 // New allocated objects may have the mark set to anonymously biased. 942 // Also the deoptimized method may called methods with synchronization 943 // where the thread-local object is bias locked to the current thread. 944 assert(mark->is_biased_anonymously() || 945 mark->biased_locker() == thread, "should be locked to current thread"); 946 // Reset mark word to unbiased prototype. 947 markOop unbiased_prototype = markOopDesc::prototype()->set_age(mark->age()); 948 obj->set_mark(unbiased_prototype); 949 } 950 BasicLock* lock = mon_info->lock(); 951 ObjectSynchronizer::slow_enter(obj, lock, thread); 952 } 953 assert(mon_info->owner()->is_locked(), "object must be locked now"); 954 } 955 } 956 957 958 #ifndef PRODUCT 959 // print information about reallocated objects 960 void Deoptimization::print_objects(GrowableArray<ScopeValue*>* objects) { 961 fieldDescriptor fd; 962 963 for (int i = 0; i < objects->length(); i++) { 964 ObjectValue* sv = (ObjectValue*) objects->at(i); 965 KlassHandle k(((ConstantOopReadValue*) sv->klass())->value()()); 966 Handle obj = sv->value(); 967 968 tty->print(" object <" INTPTR_FORMAT "> of type ", sv->value()()); 969 k->as_klassOop()->print_value(); 970 tty->print(" allocated (%d bytes)", obj->size() * HeapWordSize); 971 tty->cr(); 972 973 if (Verbose) { 974 k->oop_print_on(obj(), tty); 975 } 976 } 977 } 978 #endif 979 #endif // COMPILER2 980 981 vframeArray* Deoptimization::create_vframeArray(JavaThread* thread, frame fr, RegisterMap *reg_map, GrowableArray<compiledVFrame*>* chunk) { 982 983 #ifndef PRODUCT 984 if (TraceDeoptimization) { 985 ttyLocker ttyl; 986 tty->print("DEOPT PACKING thread " INTPTR_FORMAT " ", thread); 987 fr.print_on(tty); 988 tty->print_cr(" Virtual frames (innermost first):"); 989 for (int index = 0; index < chunk->length(); index++) { 990 compiledVFrame* vf = chunk->at(index); 991 tty->print(" %2d - ", index); 992 vf->print_value(); 993 int bci = chunk->at(index)->raw_bci(); 994 const char* code_name; 995 if (bci == SynchronizationEntryBCI) { 996 code_name = "sync entry"; 997 } else { 998 Bytecodes::Code code = vf->method()->code_at(bci); 999 code_name = Bytecodes::name(code); 1000 } 1001 tty->print(" - %s", code_name); 1002 tty->print_cr(" @ bci %d ", bci); 1003 if (Verbose) { 1004 vf->print(); 1005 tty->cr(); 1006 } 1007 } 1008 } 1009 #endif 1010 1011 // Register map for next frame (used for stack crawl). We capture 1012 // the state of the deopt'ing frame's caller. Thus if we need to 1013 // stuff a C2I adapter we can properly fill in the callee-save 1014 // register locations. 1015 frame caller = fr.sender(reg_map); 1016 int frame_size = caller.sp() - fr.sp(); 1017 1018 frame sender = caller; 1019 1020 // Since the Java thread being deoptimized will eventually adjust it's own stack, 1021 // the vframeArray containing the unpacking information is allocated in the C heap. 1022 // For Compiler1, the caller of the deoptimized frame is saved for use by unpack_frames(). 1023 vframeArray* array = vframeArray::allocate(thread, frame_size, chunk, reg_map, sender, caller, fr); 1024 1025 // Compare the vframeArray to the collected vframes 1026 assert(array->structural_compare(thread, chunk), "just checking"); 1027 Events::log("# vframes = %d", (intptr_t)chunk->length()); 1028 1029 #ifndef PRODUCT 1030 if (TraceDeoptimization) { 1031 ttyLocker ttyl; 1032 tty->print_cr(" Created vframeArray " INTPTR_FORMAT, array); 1033 } 1034 #endif // PRODUCT 1035 1036 return array; 1037 } 1038 1039 1040 static void collect_monitors(compiledVFrame* cvf, GrowableArray<Handle>* objects_to_revoke) { 1041 GrowableArray<MonitorInfo*>* monitors = cvf->monitors(); 1042 for (int i = 0; i < monitors->length(); i++) { 1043 MonitorInfo* mon_info = monitors->at(i); 1044 if (!mon_info->eliminated() && mon_info->owner() != NULL) { 1045 objects_to_revoke->append(Handle(mon_info->owner())); 1046 } 1047 } 1048 } 1049 1050 1051 void Deoptimization::revoke_biases_of_monitors(JavaThread* thread, frame fr, RegisterMap* map) { 1052 if (!UseBiasedLocking) { 1053 return; 1054 } 1055 1056 GrowableArray<Handle>* objects_to_revoke = new GrowableArray<Handle>(); 1057 1058 // Unfortunately we don't have a RegisterMap available in most of 1059 // the places we want to call this routine so we need to walk the 1060 // stack again to update the register map. 1061 if (map == NULL || !map->update_map()) { 1062 StackFrameStream sfs(thread, true); 1063 bool found = false; 1064 while (!found && !sfs.is_done()) { 1065 frame* cur = sfs.current(); 1066 sfs.next(); 1067 found = cur->id() == fr.id(); 1068 } 1069 assert(found, "frame to be deoptimized not found on target thread's stack"); 1070 map = sfs.register_map(); 1071 } 1072 1073 vframe* vf = vframe::new_vframe(&fr, map, thread); 1074 compiledVFrame* cvf = compiledVFrame::cast(vf); 1075 // Revoke monitors' biases in all scopes 1076 while (!cvf->is_top()) { 1077 collect_monitors(cvf, objects_to_revoke); 1078 cvf = compiledVFrame::cast(cvf->sender()); 1079 } 1080 collect_monitors(cvf, objects_to_revoke); 1081 1082 if (SafepointSynchronize::is_at_safepoint()) { 1083 BiasedLocking::revoke_at_safepoint(objects_to_revoke); 1084 } else { 1085 BiasedLocking::revoke(objects_to_revoke); 1086 } 1087 } 1088 1089 1090 void Deoptimization::revoke_biases_of_monitors(CodeBlob* cb) { 1091 if (!UseBiasedLocking) { 1092 return; 1093 } 1094 1095 assert(SafepointSynchronize::is_at_safepoint(), "must only be called from safepoint"); 1096 GrowableArray<Handle>* objects_to_revoke = new GrowableArray<Handle>(); 1097 for (JavaThread* jt = Threads::first(); jt != NULL ; jt = jt->next()) { 1098 if (jt->has_last_Java_frame()) { 1099 StackFrameStream sfs(jt, true); 1100 while (!sfs.is_done()) { 1101 frame* cur = sfs.current(); 1102 if (cb->contains(cur->pc())) { 1103 vframe* vf = vframe::new_vframe(cur, sfs.register_map(), jt); 1104 compiledVFrame* cvf = compiledVFrame::cast(vf); 1105 // Revoke monitors' biases in all scopes 1106 while (!cvf->is_top()) { 1107 collect_monitors(cvf, objects_to_revoke); 1108 cvf = compiledVFrame::cast(cvf->sender()); 1109 } 1110 collect_monitors(cvf, objects_to_revoke); 1111 } 1112 sfs.next(); 1113 } 1114 } 1115 } 1116 BiasedLocking::revoke_at_safepoint(objects_to_revoke); 1117 } 1118 1119 1120 void Deoptimization::deoptimize_single_frame(JavaThread* thread, frame fr) { 1121 assert(fr.can_be_deoptimized(), "checking frame type"); 1122 1123 gather_statistics(Reason_constraint, Action_none, Bytecodes::_illegal); 1124 1125 EventMark m("Deoptimization (pc=" INTPTR_FORMAT ", sp=" INTPTR_FORMAT ")", fr.pc(), fr.id()); 1126 1127 // Patch the nmethod so that when execution returns to it we will 1128 // deopt the execution state and return to the interpreter. 1129 fr.deoptimize(thread); 1130 } 1131 1132 void Deoptimization::deoptimize(JavaThread* thread, frame fr, RegisterMap *map) { 1133 // Deoptimize only if the frame comes from compile code. 1134 // Do not deoptimize the frame which is already patched 1135 // during the execution of the loops below. 1136 if (!fr.is_compiled_frame() || fr.is_deoptimized_frame()) { 1137 return; 1138 } 1139 ResourceMark rm; 1140 DeoptimizationMarker dm; 1141 if (UseBiasedLocking) { 1142 revoke_biases_of_monitors(thread, fr, map); 1143 } 1144 deoptimize_single_frame(thread, fr); 1145 1146 } 1147 1148 1149 void Deoptimization::deoptimize_frame_internal(JavaThread* thread, intptr_t* id) { 1150 assert(thread == Thread::current() || SafepointSynchronize::is_at_safepoint(), 1151 "can only deoptimize other thread at a safepoint"); 1152 // Compute frame and register map based on thread and sp. 1153 RegisterMap reg_map(thread, UseBiasedLocking); 1154 frame fr = thread->last_frame(); 1155 while (fr.id() != id) { 1156 fr = fr.sender(®_map); 1157 } 1158 deoptimize(thread, fr, ®_map); 1159 } 1160 1161 1162 void Deoptimization::deoptimize_frame(JavaThread* thread, intptr_t* id) { 1163 if (thread == Thread::current()) { 1164 Deoptimization::deoptimize_frame_internal(thread, id); 1165 } else { 1166 VM_DeoptimizeFrame deopt(thread, id); 1167 VMThread::execute(&deopt); 1168 } 1169 } 1170 1171 1172 // JVMTI PopFrame support 1173 JRT_LEAF(void, Deoptimization::popframe_preserve_args(JavaThread* thread, int bytes_to_save, void* start_address)) 1174 { 1175 thread->popframe_preserve_args(in_ByteSize(bytes_to_save), start_address); 1176 } 1177 JRT_END 1178 1179 1180 #if defined(COMPILER2) || defined(SHARK) 1181 void Deoptimization::load_class_by_index(constantPoolHandle constant_pool, int index, TRAPS) { 1182 // in case of an unresolved klass entry, load the class. 1183 if (constant_pool->tag_at(index).is_unresolved_klass()) { 1184 klassOop tk = constant_pool->klass_at(index, CHECK); 1185 return; 1186 } 1187 1188 if (!constant_pool->tag_at(index).is_symbol()) return; 1189 1190 Handle class_loader (THREAD, instanceKlass::cast(constant_pool->pool_holder())->class_loader()); 1191 Symbol* symbol = constant_pool->symbol_at(index); 1192 1193 // class name? 1194 if (symbol->byte_at(0) != '(') { 1195 Handle protection_domain (THREAD, Klass::cast(constant_pool->pool_holder())->protection_domain()); 1196 SystemDictionary::resolve_or_null(symbol, class_loader, protection_domain, CHECK); 1197 return; 1198 } 1199 1200 // then it must be a signature! 1201 ResourceMark rm(THREAD); 1202 for (SignatureStream ss(symbol); !ss.is_done(); ss.next()) { 1203 if (ss.is_object()) { 1204 Symbol* class_name = ss.as_symbol(CHECK); 1205 Handle protection_domain (THREAD, Klass::cast(constant_pool->pool_holder())->protection_domain()); 1206 SystemDictionary::resolve_or_null(class_name, class_loader, protection_domain, CHECK); 1207 } 1208 } 1209 } 1210 1211 1212 void Deoptimization::load_class_by_index(constantPoolHandle constant_pool, int index) { 1213 EXCEPTION_MARK; 1214 load_class_by_index(constant_pool, index, THREAD); 1215 if (HAS_PENDING_EXCEPTION) { 1216 // Exception happened during classloading. We ignore the exception here, since it 1217 // is going to be rethrown since the current activation is going to be deoptimzied and 1218 // the interpreter will re-execute the bytecode. 1219 CLEAR_PENDING_EXCEPTION; 1220 } 1221 } 1222 1223 JRT_ENTRY(void, Deoptimization::uncommon_trap_inner(JavaThread* thread, jint trap_request)) { 1224 HandleMark hm; 1225 1226 // uncommon_trap() is called at the beginning of the uncommon trap 1227 // handler. Note this fact before we start generating temporary frames 1228 // that can confuse an asynchronous stack walker. This counter is 1229 // decremented at the end of unpack_frames(). 1230 thread->inc_in_deopt_handler(); 1231 1232 // We need to update the map if we have biased locking. 1233 RegisterMap reg_map(thread, UseBiasedLocking); 1234 frame stub_frame = thread->last_frame(); 1235 frame fr = stub_frame.sender(®_map); 1236 // Make sure the calling nmethod is not getting deoptimized and removed 1237 // before we are done with it. 1238 nmethodLocker nl(fr.pc()); 1239 1240 { 1241 ResourceMark rm; 1242 1243 // Revoke biases of any monitors in the frame to ensure we can migrate them 1244 revoke_biases_of_monitors(thread, fr, ®_map); 1245 1246 DeoptReason reason = trap_request_reason(trap_request); 1247 DeoptAction action = trap_request_action(trap_request); 1248 jint unloaded_class_index = trap_request_index(trap_request); // CP idx or -1 1249 1250 Events::log("Uncommon trap occurred @" INTPTR_FORMAT " unloaded_class_index = %d", fr.pc(), (int) trap_request); 1251 vframe* vf = vframe::new_vframe(&fr, ®_map, thread); 1252 compiledVFrame* cvf = compiledVFrame::cast(vf); 1253 1254 nmethod* nm = cvf->code(); 1255 1256 ScopeDesc* trap_scope = cvf->scope(); 1257 methodHandle trap_method = trap_scope->method(); 1258 int trap_bci = trap_scope->bci(); 1259 Bytecodes::Code trap_bc = trap_method->java_code_at(trap_bci); 1260 1261 // Record this event in the histogram. 1262 gather_statistics(reason, action, trap_bc); 1263 1264 // Ensure that we can record deopt. history: 1265 bool create_if_missing = ProfileTraps; 1266 1267 methodDataHandle trap_mdo 1268 (THREAD, get_method_data(thread, trap_method, create_if_missing)); 1269 1270 // Print a bunch of diagnostics, if requested. 1271 if (TraceDeoptimization || LogCompilation) { 1272 ResourceMark rm; 1273 ttyLocker ttyl; 1274 char buf[100]; 1275 if (xtty != NULL) { 1276 xtty->begin_head("uncommon_trap thread='" UINTX_FORMAT"' %s", 1277 os::current_thread_id(), 1278 format_trap_request(buf, sizeof(buf), trap_request)); 1279 nm->log_identity(xtty); 1280 } 1281 Symbol* class_name = NULL; 1282 bool unresolved = false; 1283 if (unloaded_class_index >= 0) { 1284 constantPoolHandle constants (THREAD, trap_method->constants()); 1285 if (constants->tag_at(unloaded_class_index).is_unresolved_klass()) { 1286 class_name = constants->klass_name_at(unloaded_class_index); 1287 unresolved = true; 1288 if (xtty != NULL) 1289 xtty->print(" unresolved='1'"); 1290 } else if (constants->tag_at(unloaded_class_index).is_symbol()) { 1291 class_name = constants->symbol_at(unloaded_class_index); 1292 } 1293 if (xtty != NULL) 1294 xtty->name(class_name); 1295 } 1296 if (xtty != NULL && trap_mdo.not_null()) { 1297 // Dump the relevant MDO state. 1298 // This is the deopt count for the current reason, any previous 1299 // reasons or recompiles seen at this point. 1300 int dcnt = trap_mdo->trap_count(reason); 1301 if (dcnt != 0) 1302 xtty->print(" count='%d'", dcnt); 1303 ProfileData* pdata = trap_mdo->bci_to_data(trap_bci); 1304 int dos = (pdata == NULL)? 0: pdata->trap_state(); 1305 if (dos != 0) { 1306 xtty->print(" state='%s'", format_trap_state(buf, sizeof(buf), dos)); 1307 if (trap_state_is_recompiled(dos)) { 1308 int recnt2 = trap_mdo->overflow_recompile_count(); 1309 if (recnt2 != 0) 1310 xtty->print(" recompiles2='%d'", recnt2); 1311 } 1312 } 1313 } 1314 if (xtty != NULL) { 1315 xtty->stamp(); 1316 xtty->end_head(); 1317 } 1318 if (TraceDeoptimization) { // make noise on the tty 1319 tty->print("Uncommon trap occurred in"); 1320 nm->method()->print_short_name(tty); 1321 tty->print(" (@" INTPTR_FORMAT ") thread=%d reason=%s action=%s unloaded_class_index=%d", 1322 fr.pc(), 1323 (int) os::current_thread_id(), 1324 trap_reason_name(reason), 1325 trap_action_name(action), 1326 unloaded_class_index); 1327 if (class_name != NULL) { 1328 tty->print(unresolved ? " unresolved class: " : " symbol: "); 1329 class_name->print_symbol_on(tty); 1330 } 1331 tty->cr(); 1332 } 1333 if (xtty != NULL) { 1334 // Log the precise location of the trap. 1335 for (ScopeDesc* sd = trap_scope; ; sd = sd->sender()) { 1336 xtty->begin_elem("jvms bci='%d'", sd->bci()); 1337 xtty->method(sd->method()); 1338 xtty->end_elem(); 1339 if (sd->is_top()) break; 1340 } 1341 xtty->tail("uncommon_trap"); 1342 } 1343 } 1344 // (End diagnostic printout.) 1345 1346 // Load class if necessary 1347 if (unloaded_class_index >= 0) { 1348 constantPoolHandle constants(THREAD, trap_method->constants()); 1349 load_class_by_index(constants, unloaded_class_index); 1350 } 1351 1352 // Flush the nmethod if necessary and desirable. 1353 // 1354 // We need to avoid situations where we are re-flushing the nmethod 1355 // because of a hot deoptimization site. Repeated flushes at the same 1356 // point need to be detected by the compiler and avoided. If the compiler 1357 // cannot avoid them (or has a bug and "refuses" to avoid them), this 1358 // module must take measures to avoid an infinite cycle of recompilation 1359 // and deoptimization. There are several such measures: 1360 // 1361 // 1. If a recompilation is ordered a second time at some site X 1362 // and for the same reason R, the action is adjusted to 'reinterpret', 1363 // to give the interpreter time to exercise the method more thoroughly. 1364 // If this happens, the method's overflow_recompile_count is incremented. 1365 // 1366 // 2. If the compiler fails to reduce the deoptimization rate, then 1367 // the method's overflow_recompile_count will begin to exceed the set 1368 // limit PerBytecodeRecompilationCutoff. If this happens, the action 1369 // is adjusted to 'make_not_compilable', and the method is abandoned 1370 // to the interpreter. This is a performance hit for hot methods, 1371 // but is better than a disastrous infinite cycle of recompilations. 1372 // (Actually, only the method containing the site X is abandoned.) 1373 // 1374 // 3. In parallel with the previous measures, if the total number of 1375 // recompilations of a method exceeds the much larger set limit 1376 // PerMethodRecompilationCutoff, the method is abandoned. 1377 // This should only happen if the method is very large and has 1378 // many "lukewarm" deoptimizations. The code which enforces this 1379 // limit is elsewhere (class nmethod, class methodOopDesc). 1380 // 1381 // Note that the per-BCI 'is_recompiled' bit gives the compiler one chance 1382 // to recompile at each bytecode independently of the per-BCI cutoff. 1383 // 1384 // The decision to update code is up to the compiler, and is encoded 1385 // in the Action_xxx code. If the compiler requests Action_none 1386 // no trap state is changed, no compiled code is changed, and the 1387 // computation suffers along in the interpreter. 1388 // 1389 // The other action codes specify various tactics for decompilation 1390 // and recompilation. Action_maybe_recompile is the loosest, and 1391 // allows the compiled code to stay around until enough traps are seen, 1392 // and until the compiler gets around to recompiling the trapping method. 1393 // 1394 // The other actions cause immediate removal of the present code. 1395 1396 bool update_trap_state = true; 1397 bool make_not_entrant = false; 1398 bool make_not_compilable = false; 1399 bool reprofile = false; 1400 switch (action) { 1401 case Action_none: 1402 // Keep the old code. 1403 update_trap_state = false; 1404 break; 1405 case Action_maybe_recompile: 1406 // Do not need to invalidate the present code, but we can 1407 // initiate another 1408 // Start compiler without (necessarily) invalidating the nmethod. 1409 // The system will tolerate the old code, but new code should be 1410 // generated when possible. 1411 break; 1412 case Action_reinterpret: 1413 // Go back into the interpreter for a while, and then consider 1414 // recompiling form scratch. 1415 make_not_entrant = true; 1416 // Reset invocation counter for outer most method. 1417 // This will allow the interpreter to exercise the bytecodes 1418 // for a while before recompiling. 1419 // By contrast, Action_make_not_entrant is immediate. 1420 // 1421 // Note that the compiler will track null_check, null_assert, 1422 // range_check, and class_check events and log them as if they 1423 // had been traps taken from compiled code. This will update 1424 // the MDO trap history so that the next compilation will 1425 // properly detect hot trap sites. 1426 reprofile = true; 1427 break; 1428 case Action_make_not_entrant: 1429 // Request immediate recompilation, and get rid of the old code. 1430 // Make them not entrant, so next time they are called they get 1431 // recompiled. Unloaded classes are loaded now so recompile before next 1432 // time they are called. Same for uninitialized. The interpreter will 1433 // link the missing class, if any. 1434 make_not_entrant = true; 1435 break; 1436 case Action_make_not_compilable: 1437 // Give up on compiling this method at all. 1438 make_not_entrant = true; 1439 make_not_compilable = true; 1440 break; 1441 default: 1442 ShouldNotReachHere(); 1443 } 1444 1445 // Setting +ProfileTraps fixes the following, on all platforms: 1446 // 4852688: ProfileInterpreter is off by default for ia64. The result is 1447 // infinite heroic-opt-uncommon-trap/deopt/recompile cycles, since the 1448 // recompile relies on a methodDataOop to record heroic opt failures. 1449 1450 // Whether the interpreter is producing MDO data or not, we also need 1451 // to use the MDO to detect hot deoptimization points and control 1452 // aggressive optimization. 1453 bool inc_recompile_count = false; 1454 ProfileData* pdata = NULL; 1455 if (ProfileTraps && update_trap_state && trap_mdo.not_null()) { 1456 assert(trap_mdo() == get_method_data(thread, trap_method, false), "sanity"); 1457 uint this_trap_count = 0; 1458 bool maybe_prior_trap = false; 1459 bool maybe_prior_recompile = false; 1460 pdata = query_update_method_data(trap_mdo, trap_bci, reason, 1461 //outputs: 1462 this_trap_count, 1463 maybe_prior_trap, 1464 maybe_prior_recompile); 1465 // Because the interpreter also counts null, div0, range, and class 1466 // checks, these traps from compiled code are double-counted. 1467 // This is harmless; it just means that the PerXTrapLimit values 1468 // are in effect a little smaller than they look. 1469 1470 DeoptReason per_bc_reason = reason_recorded_per_bytecode_if_any(reason); 1471 if (per_bc_reason != Reason_none) { 1472 // Now take action based on the partially known per-BCI history. 1473 if (maybe_prior_trap 1474 && this_trap_count >= (uint)PerBytecodeTrapLimit) { 1475 // If there are too many traps at this BCI, force a recompile. 1476 // This will allow the compiler to see the limit overflow, and 1477 // take corrective action, if possible. The compiler generally 1478 // does not use the exact PerBytecodeTrapLimit value, but instead 1479 // changes its tactics if it sees any traps at all. This provides 1480 // a little hysteresis, delaying a recompile until a trap happens 1481 // several times. 1482 // 1483 // Actually, since there is only one bit of counter per BCI, 1484 // the possible per-BCI counts are {0,1,(per-method count)}. 1485 // This produces accurate results if in fact there is only 1486 // one hot trap site, but begins to get fuzzy if there are 1487 // many sites. For example, if there are ten sites each 1488 // trapping two or more times, they each get the blame for 1489 // all of their traps. 1490 make_not_entrant = true; 1491 if (per_bc_reason == Reason_unhandled) { 1492 make_not_compilable = true; 1493 } 1494 } 1495 1496 // Detect repeated recompilation at the same BCI, and enforce a limit. 1497 if (make_not_entrant && maybe_prior_recompile) { 1498 // More than one recompile at this point. 1499 inc_recompile_count = maybe_prior_trap; 1500 } 1501 } else { 1502 // For reasons which are not recorded per-bytecode, we simply 1503 // force recompiles unconditionally. 1504 // (Note that PerMethodRecompilationCutoff is enforced elsewhere.) 1505 make_not_entrant = true; 1506 } 1507 1508 // Go back to the compiler if there are too many traps in this method. 1509 if (this_trap_count >= (uint)PerMethodTrapLimit) { 1510 // If there are too many traps in this method, force a recompile. 1511 // This will allow the compiler to see the limit overflow, and 1512 // take corrective action, if possible. 1513 // (This condition is an unlikely backstop only, because the 1514 // PerBytecodeTrapLimit is more likely to take effect first, 1515 // if it is applicable.) 1516 make_not_entrant = true; 1517 } 1518 1519 // Here's more hysteresis: If there has been a recompile at 1520 // this trap point already, run the method in the interpreter 1521 // for a while to exercise it more thoroughly. 1522 if (make_not_entrant && maybe_prior_recompile && maybe_prior_trap) { 1523 reprofile = true; 1524 } 1525 1526 } 1527 1528 // Take requested actions on the method: 1529 1530 // Recompile 1531 if (make_not_entrant) { 1532 if (!nm->make_not_entrant()) { 1533 return; // the call did not change nmethod's state 1534 } 1535 1536 if (pdata != NULL) { 1537 // Record the recompilation event, if any. 1538 int tstate0 = pdata->trap_state(); 1539 int tstate1 = trap_state_set_recompiled(tstate0, true); 1540 if (tstate1 != tstate0) 1541 pdata->set_trap_state(tstate1); 1542 } 1543 } 1544 1545 if (inc_recompile_count) { 1546 trap_mdo->inc_overflow_recompile_count(); 1547 if ((uint)trap_mdo->overflow_recompile_count() > 1548 (uint)PerBytecodeRecompilationCutoff) { 1549 // Give up on the method containing the bad BCI. 1550 if (trap_method() == nm->method()) { 1551 make_not_compilable = true; 1552 } else { 1553 trap_method->set_not_compilable(CompLevel_full_optimization); 1554 // But give grace to the enclosing nm->method(). 1555 } 1556 } 1557 } 1558 1559 // Reprofile 1560 if (reprofile) { 1561 CompilationPolicy::policy()->reprofile(trap_scope, nm->is_osr_method()); 1562 } 1563 1564 // Give up compiling 1565 if (make_not_compilable && !nm->method()->is_not_compilable(CompLevel_full_optimization)) { 1566 assert(make_not_entrant, "consistent"); 1567 nm->method()->set_not_compilable(CompLevel_full_optimization); 1568 } 1569 1570 } // Free marked resources 1571 1572 } 1573 JRT_END 1574 1575 methodDataOop 1576 Deoptimization::get_method_data(JavaThread* thread, methodHandle m, 1577 bool create_if_missing) { 1578 Thread* THREAD = thread; 1579 methodDataOop mdo = m()->method_data(); 1580 if (mdo == NULL && create_if_missing && !HAS_PENDING_EXCEPTION) { 1581 // Build an MDO. Ignore errors like OutOfMemory; 1582 // that simply means we won't have an MDO to update. 1583 methodOopDesc::build_interpreter_method_data(m, THREAD); 1584 if (HAS_PENDING_EXCEPTION) { 1585 assert((PENDING_EXCEPTION->is_a(SystemDictionary::OutOfMemoryError_klass())), "we expect only an OOM error here"); 1586 CLEAR_PENDING_EXCEPTION; 1587 } 1588 mdo = m()->method_data(); 1589 } 1590 return mdo; 1591 } 1592 1593 ProfileData* 1594 Deoptimization::query_update_method_data(methodDataHandle trap_mdo, 1595 int trap_bci, 1596 Deoptimization::DeoptReason reason, 1597 //outputs: 1598 uint& ret_this_trap_count, 1599 bool& ret_maybe_prior_trap, 1600 bool& ret_maybe_prior_recompile) { 1601 uint prior_trap_count = trap_mdo->trap_count(reason); 1602 uint this_trap_count = trap_mdo->inc_trap_count(reason); 1603 1604 // If the runtime cannot find a place to store trap history, 1605 // it is estimated based on the general condition of the method. 1606 // If the method has ever been recompiled, or has ever incurred 1607 // a trap with the present reason , then this BCI is assumed 1608 // (pessimistically) to be the culprit. 1609 bool maybe_prior_trap = (prior_trap_count != 0); 1610 bool maybe_prior_recompile = (trap_mdo->decompile_count() != 0); 1611 ProfileData* pdata = NULL; 1612 1613 // For reasons which are recorded per bytecode, we check per-BCI data. 1614 DeoptReason per_bc_reason = reason_recorded_per_bytecode_if_any(reason); 1615 if (per_bc_reason != Reason_none) { 1616 // Find the profile data for this BCI. If there isn't one, 1617 // try to allocate one from the MDO's set of spares. 1618 // This will let us detect a repeated trap at this point. 1619 pdata = trap_mdo->allocate_bci_to_data(trap_bci); 1620 1621 if (pdata != NULL) { 1622 // Query the trap state of this profile datum. 1623 int tstate0 = pdata->trap_state(); 1624 if (!trap_state_has_reason(tstate0, per_bc_reason)) 1625 maybe_prior_trap = false; 1626 if (!trap_state_is_recompiled(tstate0)) 1627 maybe_prior_recompile = false; 1628 1629 // Update the trap state of this profile datum. 1630 int tstate1 = tstate0; 1631 // Record the reason. 1632 tstate1 = trap_state_add_reason(tstate1, per_bc_reason); 1633 // Store the updated state on the MDO, for next time. 1634 if (tstate1 != tstate0) 1635 pdata->set_trap_state(tstate1); 1636 } else { 1637 if (LogCompilation && xtty != NULL) { 1638 ttyLocker ttyl; 1639 // Missing MDP? Leave a small complaint in the log. 1640 xtty->elem("missing_mdp bci='%d'", trap_bci); 1641 } 1642 } 1643 } 1644 1645 // Return results: 1646 ret_this_trap_count = this_trap_count; 1647 ret_maybe_prior_trap = maybe_prior_trap; 1648 ret_maybe_prior_recompile = maybe_prior_recompile; 1649 return pdata; 1650 } 1651 1652 void 1653 Deoptimization::update_method_data_from_interpreter(methodDataHandle trap_mdo, int trap_bci, int reason) { 1654 ResourceMark rm; 1655 // Ignored outputs: 1656 uint ignore_this_trap_count; 1657 bool ignore_maybe_prior_trap; 1658 bool ignore_maybe_prior_recompile; 1659 query_update_method_data(trap_mdo, trap_bci, 1660 (DeoptReason)reason, 1661 ignore_this_trap_count, 1662 ignore_maybe_prior_trap, 1663 ignore_maybe_prior_recompile); 1664 } 1665 1666 Deoptimization::UnrollBlock* Deoptimization::uncommon_trap(JavaThread* thread, jint trap_request) { 1667 1668 // Still in Java no safepoints 1669 { 1670 // This enters VM and may safepoint 1671 uncommon_trap_inner(thread, trap_request); 1672 } 1673 return fetch_unroll_info_helper(thread); 1674 } 1675 1676 // Local derived constants. 1677 // Further breakdown of DataLayout::trap_state, as promised by DataLayout. 1678 const int DS_REASON_MASK = DataLayout::trap_mask >> 1; 1679 const int DS_RECOMPILE_BIT = DataLayout::trap_mask - DS_REASON_MASK; 1680 1681 //---------------------------trap_state_reason--------------------------------- 1682 Deoptimization::DeoptReason 1683 Deoptimization::trap_state_reason(int trap_state) { 1684 // This assert provides the link between the width of DataLayout::trap_bits 1685 // and the encoding of "recorded" reasons. It ensures there are enough 1686 // bits to store all needed reasons in the per-BCI MDO profile. 1687 assert(DS_REASON_MASK >= Reason_RECORDED_LIMIT, "enough bits"); 1688 int recompile_bit = (trap_state & DS_RECOMPILE_BIT); 1689 trap_state -= recompile_bit; 1690 if (trap_state == DS_REASON_MASK) { 1691 return Reason_many; 1692 } else { 1693 assert((int)Reason_none == 0, "state=0 => Reason_none"); 1694 return (DeoptReason)trap_state; 1695 } 1696 } 1697 //-------------------------trap_state_has_reason------------------------------- 1698 int Deoptimization::trap_state_has_reason(int trap_state, int reason) { 1699 assert(reason_is_recorded_per_bytecode((DeoptReason)reason), "valid reason"); 1700 assert(DS_REASON_MASK >= Reason_RECORDED_LIMIT, "enough bits"); 1701 int recompile_bit = (trap_state & DS_RECOMPILE_BIT); 1702 trap_state -= recompile_bit; 1703 if (trap_state == DS_REASON_MASK) { 1704 return -1; // true, unspecifically (bottom of state lattice) 1705 } else if (trap_state == reason) { 1706 return 1; // true, definitely 1707 } else if (trap_state == 0) { 1708 return 0; // false, definitely (top of state lattice) 1709 } else { 1710 return 0; // false, definitely 1711 } 1712 } 1713 //-------------------------trap_state_add_reason------------------------------- 1714 int Deoptimization::trap_state_add_reason(int trap_state, int reason) { 1715 assert(reason_is_recorded_per_bytecode((DeoptReason)reason) || reason == Reason_many, "valid reason"); 1716 int recompile_bit = (trap_state & DS_RECOMPILE_BIT); 1717 trap_state -= recompile_bit; 1718 if (trap_state == DS_REASON_MASK) { 1719 return trap_state + recompile_bit; // already at state lattice bottom 1720 } else if (trap_state == reason) { 1721 return trap_state + recompile_bit; // the condition is already true 1722 } else if (trap_state == 0) { 1723 return reason + recompile_bit; // no condition has yet been true 1724 } else { 1725 return DS_REASON_MASK + recompile_bit; // fall to state lattice bottom 1726 } 1727 } 1728 //-----------------------trap_state_is_recompiled------------------------------ 1729 bool Deoptimization::trap_state_is_recompiled(int trap_state) { 1730 return (trap_state & DS_RECOMPILE_BIT) != 0; 1731 } 1732 //-----------------------trap_state_set_recompiled----------------------------- 1733 int Deoptimization::trap_state_set_recompiled(int trap_state, bool z) { 1734 if (z) return trap_state | DS_RECOMPILE_BIT; 1735 else return trap_state & ~DS_RECOMPILE_BIT; 1736 } 1737 //---------------------------format_trap_state--------------------------------- 1738 // This is used for debugging and diagnostics, including hotspot.log output. 1739 const char* Deoptimization::format_trap_state(char* buf, size_t buflen, 1740 int trap_state) { 1741 DeoptReason reason = trap_state_reason(trap_state); 1742 bool recomp_flag = trap_state_is_recompiled(trap_state); 1743 // Re-encode the state from its decoded components. 1744 int decoded_state = 0; 1745 if (reason_is_recorded_per_bytecode(reason) || reason == Reason_many) 1746 decoded_state = trap_state_add_reason(decoded_state, reason); 1747 if (recomp_flag) 1748 decoded_state = trap_state_set_recompiled(decoded_state, recomp_flag); 1749 // If the state re-encodes properly, format it symbolically. 1750 // Because this routine is used for debugging and diagnostics, 1751 // be robust even if the state is a strange value. 1752 size_t len; 1753 if (decoded_state != trap_state) { 1754 // Random buggy state that doesn't decode?? 1755 len = jio_snprintf(buf, buflen, "#%d", trap_state); 1756 } else { 1757 len = jio_snprintf(buf, buflen, "%s%s", 1758 trap_reason_name(reason), 1759 recomp_flag ? " recompiled" : ""); 1760 } 1761 if (len >= buflen) 1762 buf[buflen-1] = '\0'; 1763 return buf; 1764 } 1765 1766 1767 //--------------------------------statics-------------------------------------- 1768 Deoptimization::DeoptAction Deoptimization::_unloaded_action 1769 = Deoptimization::Action_reinterpret; 1770 const char* Deoptimization::_trap_reason_name[Reason_LIMIT] = { 1771 // Note: Keep this in sync. with enum DeoptReason. 1772 "none", 1773 "null_check", 1774 "null_assert", 1775 "range_check", 1776 "class_check", 1777 "array_check", 1778 "intrinsic", 1779 "bimorphic", 1780 "unloaded", 1781 "uninitialized", 1782 "unreached", 1783 "unhandled", 1784 "constraint", 1785 "div0_check", 1786 "age", 1787 "predicate", 1788 "loop_limit_check" 1789 }; 1790 const char* Deoptimization::_trap_action_name[Action_LIMIT] = { 1791 // Note: Keep this in sync. with enum DeoptAction. 1792 "none", 1793 "maybe_recompile", 1794 "reinterpret", 1795 "make_not_entrant", 1796 "make_not_compilable" 1797 }; 1798 1799 const char* Deoptimization::trap_reason_name(int reason) { 1800 if (reason == Reason_many) return "many"; 1801 if ((uint)reason < Reason_LIMIT) 1802 return _trap_reason_name[reason]; 1803 static char buf[20]; 1804 sprintf(buf, "reason%d", reason); 1805 return buf; 1806 } 1807 const char* Deoptimization::trap_action_name(int action) { 1808 if ((uint)action < Action_LIMIT) 1809 return _trap_action_name[action]; 1810 static char buf[20]; 1811 sprintf(buf, "action%d", action); 1812 return buf; 1813 } 1814 1815 // This is used for debugging and diagnostics, including hotspot.log output. 1816 const char* Deoptimization::format_trap_request(char* buf, size_t buflen, 1817 int trap_request) { 1818 jint unloaded_class_index = trap_request_index(trap_request); 1819 const char* reason = trap_reason_name(trap_request_reason(trap_request)); 1820 const char* action = trap_action_name(trap_request_action(trap_request)); 1821 size_t len; 1822 if (unloaded_class_index < 0) { 1823 len = jio_snprintf(buf, buflen, "reason='%s' action='%s'", 1824 reason, action); 1825 } else { 1826 len = jio_snprintf(buf, buflen, "reason='%s' action='%s' index='%d'", 1827 reason, action, unloaded_class_index); 1828 } 1829 if (len >= buflen) 1830 buf[buflen-1] = '\0'; 1831 return buf; 1832 } 1833 1834 juint Deoptimization::_deoptimization_hist 1835 [Deoptimization::Reason_LIMIT] 1836 [1 + Deoptimization::Action_LIMIT] 1837 [Deoptimization::BC_CASE_LIMIT] 1838 = {0}; 1839 1840 enum { 1841 LSB_BITS = 8, 1842 LSB_MASK = right_n_bits(LSB_BITS) 1843 }; 1844 1845 void Deoptimization::gather_statistics(DeoptReason reason, DeoptAction action, 1846 Bytecodes::Code bc) { 1847 assert(reason >= 0 && reason < Reason_LIMIT, "oob"); 1848 assert(action >= 0 && action < Action_LIMIT, "oob"); 1849 _deoptimization_hist[Reason_none][0][0] += 1; // total 1850 _deoptimization_hist[reason][0][0] += 1; // per-reason total 1851 juint* cases = _deoptimization_hist[reason][1+action]; 1852 juint* bc_counter_addr = NULL; 1853 juint bc_counter = 0; 1854 // Look for an unused counter, or an exact match to this BC. 1855 if (bc != Bytecodes::_illegal) { 1856 for (int bc_case = 0; bc_case < BC_CASE_LIMIT; bc_case++) { 1857 juint* counter_addr = &cases[bc_case]; 1858 juint counter = *counter_addr; 1859 if ((counter == 0 && bc_counter_addr == NULL) 1860 || (Bytecodes::Code)(counter & LSB_MASK) == bc) { 1861 // this counter is either free or is already devoted to this BC 1862 bc_counter_addr = counter_addr; 1863 bc_counter = counter | bc; 1864 } 1865 } 1866 } 1867 if (bc_counter_addr == NULL) { 1868 // Overflow, or no given bytecode. 1869 bc_counter_addr = &cases[BC_CASE_LIMIT-1]; 1870 bc_counter = (*bc_counter_addr & ~LSB_MASK); // clear LSB 1871 } 1872 *bc_counter_addr = bc_counter + (1 << LSB_BITS); 1873 } 1874 1875 jint Deoptimization::total_deoptimization_count() { 1876 return _deoptimization_hist[Reason_none][0][0]; 1877 } 1878 1879 jint Deoptimization::deoptimization_count(DeoptReason reason) { 1880 assert(reason >= 0 && reason < Reason_LIMIT, "oob"); 1881 return _deoptimization_hist[reason][0][0]; 1882 } 1883 1884 void Deoptimization::print_statistics() { 1885 juint total = total_deoptimization_count(); 1886 juint account = total; 1887 if (total != 0) { 1888 ttyLocker ttyl; 1889 if (xtty != NULL) xtty->head("statistics type='deoptimization'"); 1890 tty->print_cr("Deoptimization traps recorded:"); 1891 #define PRINT_STAT_LINE(name, r) \ 1892 tty->print_cr(" %4d (%4.1f%%) %s", (int)(r), ((r) * 100.0) / total, name); 1893 PRINT_STAT_LINE("total", total); 1894 // For each non-zero entry in the histogram, print the reason, 1895 // the action, and (if specifically known) the type of bytecode. 1896 for (int reason = 0; reason < Reason_LIMIT; reason++) { 1897 for (int action = 0; action < Action_LIMIT; action++) { 1898 juint* cases = _deoptimization_hist[reason][1+action]; 1899 for (int bc_case = 0; bc_case < BC_CASE_LIMIT; bc_case++) { 1900 juint counter = cases[bc_case]; 1901 if (counter != 0) { 1902 char name[1*K]; 1903 Bytecodes::Code bc = (Bytecodes::Code)(counter & LSB_MASK); 1904 if (bc_case == BC_CASE_LIMIT && (int)bc == 0) 1905 bc = Bytecodes::_illegal; 1906 sprintf(name, "%s/%s/%s", 1907 trap_reason_name(reason), 1908 trap_action_name(action), 1909 Bytecodes::is_defined(bc)? Bytecodes::name(bc): "other"); 1910 juint r = counter >> LSB_BITS; 1911 tty->print_cr(" %40s: " UINT32_FORMAT " (%.1f%%)", name, r, (r * 100.0) / total); 1912 account -= r; 1913 } 1914 } 1915 } 1916 } 1917 if (account != 0) { 1918 PRINT_STAT_LINE("unaccounted", account); 1919 } 1920 #undef PRINT_STAT_LINE 1921 if (xtty != NULL) xtty->tail("statistics"); 1922 } 1923 } 1924 #else // COMPILER2 || SHARK 1925 1926 1927 // Stubs for C1 only system. 1928 bool Deoptimization::trap_state_is_recompiled(int trap_state) { 1929 return false; 1930 } 1931 1932 const char* Deoptimization::trap_reason_name(int reason) { 1933 return "unknown"; 1934 } 1935 1936 void Deoptimization::print_statistics() { 1937 // no output 1938 } 1939 1940 void 1941 Deoptimization::update_method_data_from_interpreter(methodDataHandle trap_mdo, int trap_bci, int reason) { 1942 // no udpate 1943 } 1944 1945 int Deoptimization::trap_state_has_reason(int trap_state, int reason) { 1946 return 0; 1947 } 1948 1949 void Deoptimization::gather_statistics(DeoptReason reason, DeoptAction action, 1950 Bytecodes::Code bc) { 1951 // no update 1952 } 1953 1954 const char* Deoptimization::format_trap_state(char* buf, size_t buflen, 1955 int trap_state) { 1956 jio_snprintf(buf, buflen, "#%d", trap_state); 1957 return buf; 1958 } 1959 1960 #endif // COMPILER2 || SHARK