1 /* 2 * Copyright (c) 1997, 2013, 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/method.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_32 85 # include "adfiles/ad_ppc_32.hpp" 86 #endif 87 #ifdef TARGET_ARCH_MODEL_ppc_64 88 # include "adfiles/ad_ppc_64.hpp" 89 #endif 90 #endif // COMPILER2 91 92 bool DeoptimizationMarker::_is_active = false; 93 94 Deoptimization::UnrollBlock::UnrollBlock(int size_of_deoptimized_frame, 95 int caller_adjustment, 96 int caller_actual_parameters, 97 int number_of_frames, 98 intptr_t* frame_sizes, 99 address* frame_pcs, 100 BasicType return_type) { 101 _size_of_deoptimized_frame = size_of_deoptimized_frame; 102 _caller_adjustment = caller_adjustment; 103 _caller_actual_parameters = caller_actual_parameters; 104 _number_of_frames = number_of_frames; 105 _frame_sizes = frame_sizes; 106 _frame_pcs = frame_pcs; 107 _register_block = NEW_C_HEAP_ARRAY(intptr_t, RegisterMap::reg_count * 2, mtCompiler); 108 _return_type = return_type; 109 _initial_info = 0; 110 // PD (x86 only) 111 _counter_temp = 0; 112 _unpack_kind = 0; 113 _sender_sp_temp = 0; 114 115 _total_frame_sizes = size_of_frames(); 116 } 117 118 119 Deoptimization::UnrollBlock::~UnrollBlock() { 120 FREE_C_HEAP_ARRAY(intptr_t, _frame_sizes, mtCompiler); 121 FREE_C_HEAP_ARRAY(intptr_t, _frame_pcs, mtCompiler); 122 FREE_C_HEAP_ARRAY(intptr_t, _register_block, mtCompiler); 123 } 124 125 126 intptr_t* Deoptimization::UnrollBlock::value_addr_at(int register_number) const { 127 assert(register_number < RegisterMap::reg_count, "checking register number"); 128 return &_register_block[register_number * 2]; 129 } 130 131 132 133 int Deoptimization::UnrollBlock::size_of_frames() const { 134 // Acount first for the adjustment of the initial frame 135 int result = _caller_adjustment; 136 for (int index = 0; index < number_of_frames(); index++) { 137 result += frame_sizes()[index]; 138 } 139 return result; 140 } 141 142 143 void Deoptimization::UnrollBlock::print() { 144 ttyLocker ttyl; 145 tty->print_cr("UnrollBlock"); 146 tty->print_cr(" size_of_deoptimized_frame = %d", _size_of_deoptimized_frame); 147 tty->print( " frame_sizes: "); 148 for (int index = 0; index < number_of_frames(); index++) { 149 tty->print("%d ", frame_sizes()[index]); 150 } 151 tty->cr(); 152 } 153 154 155 // In order to make fetch_unroll_info work properly with escape 156 // analysis, The method was changed from JRT_LEAF to JRT_BLOCK_ENTRY and 157 // ResetNoHandleMark and HandleMark were removed from it. The actual reallocation 158 // of previously eliminated objects occurs in realloc_objects, which is 159 // called from the method fetch_unroll_info_helper below. 160 JRT_BLOCK_ENTRY(Deoptimization::UnrollBlock*, Deoptimization::fetch_unroll_info(JavaThread* thread)) 161 // It is actually ok to allocate handles in a leaf method. It causes no safepoints, 162 // but makes the entry a little slower. There is however a little dance we have to 163 // do in debug mode to get around the NoHandleMark code in the JRT_LEAF macro 164 165 // fetch_unroll_info() is called at the beginning of the deoptimization 166 // handler. Note this fact before we start generating temporary frames 167 // that can confuse an asynchronous stack walker. This counter is 168 // decremented at the end of unpack_frames(). 169 thread->inc_in_deopt_handler(); 170 171 return fetch_unroll_info_helper(thread); 172 JRT_END 173 174 175 // This is factored, since it is both called from a JRT_LEAF (deoptimization) and a JRT_ENTRY (uncommon_trap) 176 Deoptimization::UnrollBlock* Deoptimization::fetch_unroll_info_helper(JavaThread* thread) { 177 178 // Note: there is a safepoint safety issue here. No matter whether we enter 179 // via vanilla deopt or uncommon trap we MUST NOT stop at a safepoint once 180 // the vframeArray is created. 181 // 182 183 // Allocate our special deoptimization ResourceMark 184 DeoptResourceMark* dmark = new DeoptResourceMark(thread); 185 assert(thread->deopt_mark() == NULL, "Pending deopt!"); 186 thread->set_deopt_mark(dmark); 187 188 frame stub_frame = thread->last_frame(); // Makes stack walkable as side effect 189 RegisterMap map(thread, true); 190 RegisterMap dummy_map(thread, false); 191 // Now get the deoptee with a valid map 192 frame deoptee = stub_frame.sender(&map); 193 // Set the deoptee nmethod 194 assert(thread->deopt_nmethod() == NULL, "Pending deopt!"); 195 thread->set_deopt_nmethod(deoptee.cb()->as_nmethod_or_null()); 196 197 if (VerifyStack) { 198 thread->validate_frame_layout(); 199 } 200 201 // Create a growable array of VFrames where each VFrame represents an inlined 202 // Java frame. This storage is allocated with the usual system arena. 203 assert(deoptee.is_compiled_frame(), "Wrong frame type"); 204 GrowableArray<compiledVFrame*>* chunk = new GrowableArray<compiledVFrame*>(10); 205 vframe* vf = vframe::new_vframe(&deoptee, &map, thread); 206 while (!vf->is_top()) { 207 assert(vf->is_compiled_frame(), "Wrong frame type"); 208 chunk->push(compiledVFrame::cast(vf)); 209 vf = vf->sender(); 210 } 211 assert(vf->is_compiled_frame(), "Wrong frame type"); 212 chunk->push(compiledVFrame::cast(vf)); 213 214 #ifdef COMPILER2 215 // Reallocate the non-escaping objects and restore their fields. Then 216 // relock objects if synchronization on them was eliminated. 217 if (DoEscapeAnalysis || EliminateNestedLocks) { 218 if (EliminateAllocations) { 219 assert (chunk->at(0)->scope() != NULL,"expect only compiled java frames"); 220 GrowableArray<ScopeValue*>* objects = chunk->at(0)->scope()->objects(); 221 222 // The flag return_oop() indicates call sites which return oop 223 // in compiled code. Such sites include java method calls, 224 // runtime calls (for example, used to allocate new objects/arrays 225 // on slow code path) and any other calls generated in compiled code. 226 // It is not guaranteed that we can get such information here only 227 // by analyzing bytecode in deoptimized frames. This is why this flag 228 // is set during method compilation (see Compile::Process_OopMap_Node()). 229 bool save_oop_result = chunk->at(0)->scope()->return_oop(); 230 Handle return_value; 231 if (save_oop_result) { 232 // Reallocation may trigger GC. If deoptimization happened on return from 233 // call which returns oop we need to save it since it is not in oopmap. 234 oop result = deoptee.saved_oop_result(&map); 235 assert(result == NULL || result->is_oop(), "must be oop"); 236 return_value = Handle(thread, result); 237 assert(Universe::heap()->is_in_or_null(result), "must be heap pointer"); 238 if (TraceDeoptimization) { 239 ttyLocker ttyl; 240 tty->print_cr("SAVED OOP RESULT " INTPTR_FORMAT " in thread " INTPTR_FORMAT, (void *)result, thread); 241 } 242 } 243 bool reallocated = false; 244 if (objects != NULL) { 245 JRT_BLOCK 246 reallocated = realloc_objects(thread, &deoptee, objects, THREAD); 247 JRT_END 248 } 249 if (reallocated) { 250 reassign_fields(&deoptee, &map, objects); 251 #ifndef PRODUCT 252 if (TraceDeoptimization) { 253 ttyLocker ttyl; 254 tty->print_cr("REALLOC OBJECTS in thread " INTPTR_FORMAT, thread); 255 print_objects(objects); 256 } 257 #endif 258 } 259 if (save_oop_result) { 260 // Restore result. 261 deoptee.set_saved_oop_result(&map, return_value()); 262 } 263 } 264 if (EliminateLocks) { 265 #ifndef PRODUCT 266 bool first = true; 267 #endif 268 for (int i = 0; i < chunk->length(); i++) { 269 compiledVFrame* cvf = chunk->at(i); 270 assert (cvf->scope() != NULL,"expect only compiled java frames"); 271 GrowableArray<MonitorInfo*>* monitors = cvf->monitors(); 272 if (monitors->is_nonempty()) { 273 relock_objects(monitors, thread); 274 #ifndef PRODUCT 275 if (TraceDeoptimization) { 276 ttyLocker ttyl; 277 for (int j = 0; j < monitors->length(); j++) { 278 MonitorInfo* mi = monitors->at(j); 279 if (mi->eliminated()) { 280 if (first) { 281 first = false; 282 tty->print_cr("RELOCK OBJECTS in thread " INTPTR_FORMAT, thread); 283 } 284 tty->print_cr(" object <" INTPTR_FORMAT "> locked", (void *)mi->owner()); 285 } 286 } 287 } 288 #endif 289 } 290 } 291 } 292 } 293 #endif // COMPILER2 294 // Ensure that no safepoint is taken after pointers have been stored 295 // in fields of rematerialized objects. If a safepoint occurs from here on 296 // out the java state residing in the vframeArray will be missed. 297 No_Safepoint_Verifier no_safepoint; 298 299 vframeArray* array = create_vframeArray(thread, deoptee, &map, chunk); 300 301 assert(thread->vframe_array_head() == NULL, "Pending deopt!");; 302 thread->set_vframe_array_head(array); 303 304 // Now that the vframeArray has been created if we have any deferred local writes 305 // added by jvmti then we can free up that structure as the data is now in the 306 // vframeArray 307 308 if (thread->deferred_locals() != NULL) { 309 GrowableArray<jvmtiDeferredLocalVariableSet*>* list = thread->deferred_locals(); 310 int i = 0; 311 do { 312 // Because of inlining we could have multiple vframes for a single frame 313 // and several of the vframes could have deferred writes. Find them all. 314 if (list->at(i)->id() == array->original().id()) { 315 jvmtiDeferredLocalVariableSet* dlv = list->at(i); 316 list->remove_at(i); 317 // individual jvmtiDeferredLocalVariableSet are CHeapObj's 318 delete dlv; 319 } else { 320 i++; 321 } 322 } while ( i < list->length() ); 323 if (list->length() == 0) { 324 thread->set_deferred_locals(NULL); 325 // free the list and elements back to C heap. 326 delete list; 327 } 328 329 } 330 331 #ifndef SHARK 332 // Compute the caller frame based on the sender sp of stub_frame and stored frame sizes info. 333 CodeBlob* cb = stub_frame.cb(); 334 // Verify we have the right vframeArray 335 assert(cb->frame_size() >= 0, "Unexpected frame size"); 336 intptr_t* unpack_sp = stub_frame.sp() + cb->frame_size(); 337 338 // If the deopt call site is a MethodHandle invoke call site we have 339 // to adjust the unpack_sp. 340 nmethod* deoptee_nm = deoptee.cb()->as_nmethod_or_null(); 341 if (deoptee_nm != NULL && deoptee_nm->is_method_handle_return(deoptee.pc())) 342 unpack_sp = deoptee.unextended_sp(); 343 344 #ifdef ASSERT 345 assert(cb->is_deoptimization_stub() || cb->is_uncommon_trap_stub(), "just checking"); 346 #endif 347 #else 348 intptr_t* unpack_sp = stub_frame.sender(&dummy_map).unextended_sp(); 349 #endif // !SHARK 350 351 // This is a guarantee instead of an assert because if vframe doesn't match 352 // we will unpack the wrong deoptimized frame and wind up in strange places 353 // where it will be very difficult to figure out what went wrong. Better 354 // to die an early death here than some very obscure death later when the 355 // trail is cold. 356 // Note: on ia64 this guarantee can be fooled by frames with no memory stack 357 // in that it will fail to detect a problem when there is one. This needs 358 // more work in tiger timeframe. 359 guarantee(array->unextended_sp() == unpack_sp, "vframe_array_head must contain the vframeArray to unpack"); 360 361 int number_of_frames = array->frames(); 362 363 // Compute the vframes' sizes. Note that frame_sizes[] entries are ordered from outermost to innermost 364 // virtual activation, which is the reverse of the elements in the vframes array. 365 intptr_t* frame_sizes = NEW_C_HEAP_ARRAY(intptr_t, number_of_frames, mtCompiler); 366 // +1 because we always have an interpreter return address for the final slot. 367 address* frame_pcs = NEW_C_HEAP_ARRAY(address, number_of_frames + 1, mtCompiler); 368 int popframe_extra_args = 0; 369 // Create an interpreter return address for the stub to use as its return 370 // address so the skeletal frames are perfectly walkable 371 frame_pcs[number_of_frames] = Interpreter::deopt_entry(vtos, 0); 372 373 // PopFrame requires that the preserved incoming arguments from the recently-popped topmost 374 // activation be put back on the expression stack of the caller for reexecution 375 if (JvmtiExport::can_pop_frame() && thread->popframe_forcing_deopt_reexecution()) { 376 popframe_extra_args = in_words(thread->popframe_preserved_args_size_in_words()); 377 } 378 379 // Find the current pc for sender of the deoptee. Since the sender may have been deoptimized 380 // itself since the deoptee vframeArray was created we must get a fresh value of the pc rather 381 // than simply use array->sender.pc(). This requires us to walk the current set of frames 382 // 383 frame deopt_sender = stub_frame.sender(&dummy_map); // First is the deoptee frame 384 deopt_sender = deopt_sender.sender(&dummy_map); // Now deoptee caller 385 386 // It's possible that the number of parameters at the call site is 387 // different than number of arguments in the callee when method 388 // handles are used. If the caller is interpreted get the real 389 // value so that the proper amount of space can be added to it's 390 // frame. 391 bool caller_was_method_handle = false; 392 if (deopt_sender.is_interpreted_frame()) { 393 methodHandle method = deopt_sender.interpreter_frame_method(); 394 Bytecode_invoke cur = Bytecode_invoke_check(method, deopt_sender.interpreter_frame_bci()); 395 if (cur.is_invokedynamic() || cur.is_invokehandle()) { 396 // Method handle invokes may involve fairly arbitrary chains of 397 // calls so it's impossible to know how much actual space the 398 // caller has for locals. 399 caller_was_method_handle = true; 400 } 401 } 402 403 // 404 // frame_sizes/frame_pcs[0] oldest frame (int or c2i) 405 // frame_sizes/frame_pcs[1] next oldest frame (int) 406 // frame_sizes/frame_pcs[n] youngest frame (int) 407 // 408 // Now a pc in frame_pcs is actually the return address to the frame's caller (a frame 409 // owns the space for the return address to it's caller). Confusing ain't it. 410 // 411 // The vframe array can address vframes with indices running from 412 // 0.._frames-1. Index 0 is the youngest frame and _frame - 1 is the oldest (root) frame. 413 // When we create the skeletal frames we need the oldest frame to be in the zero slot 414 // in the frame_sizes/frame_pcs so the assembly code can do a trivial walk. 415 // so things look a little strange in this loop. 416 // 417 int callee_parameters = 0; 418 int callee_locals = 0; 419 for (int index = 0; index < array->frames(); index++ ) { 420 // frame[number_of_frames - 1 ] = on_stack_size(youngest) 421 // frame[number_of_frames - 2 ] = on_stack_size(sender(youngest)) 422 // frame[number_of_frames - 3 ] = on_stack_size(sender(sender(youngest))) 423 int caller_parms = callee_parameters; 424 if ((index == array->frames() - 1) && caller_was_method_handle) { 425 caller_parms = 0; 426 } 427 frame_sizes[number_of_frames - 1 - index] = BytesPerWord * array->element(index)->on_stack_size(caller_parms, 428 callee_parameters, 429 callee_locals, 430 index == 0, 431 index == array->frames() - 1, 432 popframe_extra_args); 433 // This pc doesn't have to be perfect just good enough to identify the frame 434 // as interpreted so the skeleton frame will be walkable 435 // The correct pc will be set when the skeleton frame is completely filled out 436 // The final pc we store in the loop is wrong and will be overwritten below 437 frame_pcs[number_of_frames - 1 - index ] = Interpreter::deopt_entry(vtos, 0) - frame::pc_return_offset; 438 439 callee_parameters = array->element(index)->method()->size_of_parameters(); 440 callee_locals = array->element(index)->method()->max_locals(); 441 popframe_extra_args = 0; 442 } 443 444 // Compute whether the root vframe returns a float or double value. 445 BasicType return_type; 446 { 447 HandleMark hm; 448 methodHandle method(thread, array->element(0)->method()); 449 Bytecode_invoke invoke = Bytecode_invoke_check(method, array->element(0)->bci()); 450 return_type = invoke.is_valid() ? invoke.result_type() : T_ILLEGAL; 451 } 452 453 // Compute information for handling adapters and adjusting the frame size of the caller. 454 int caller_adjustment = 0; 455 456 // Compute the amount the oldest interpreter frame will have to adjust 457 // its caller's stack by. If the caller is a compiled frame then 458 // we pretend that the callee has no parameters so that the 459 // extension counts for the full amount of locals and not just 460 // locals-parms. This is because without a c2i adapter the parm 461 // area as created by the compiled frame will not be usable by 462 // the interpreter. (Depending on the calling convention there 463 // may not even be enough space). 464 465 // QQQ I'd rather see this pushed down into last_frame_adjust 466 // and have it take the sender (aka caller). 467 468 if (deopt_sender.is_compiled_frame() || caller_was_method_handle) { 469 caller_adjustment = last_frame_adjust(0, callee_locals); 470 } else if (callee_locals > callee_parameters) { 471 // The caller frame may need extending to accommodate 472 // non-parameter locals of the first unpacked interpreted frame. 473 // Compute that adjustment. 474 caller_adjustment = last_frame_adjust(callee_parameters, callee_locals); 475 } 476 477 // If the sender is deoptimized the we must retrieve the address of the handler 478 // since the frame will "magically" show the original pc before the deopt 479 // and we'd undo the deopt. 480 481 frame_pcs[0] = deopt_sender.raw_pc(); 482 483 #ifndef SHARK 484 assert(CodeCache::find_blob_unsafe(frame_pcs[0]) != NULL, "bad pc"); 485 #endif // SHARK 486 487 UnrollBlock* info = new UnrollBlock(array->frame_size() * BytesPerWord, 488 caller_adjustment * BytesPerWord, 489 caller_was_method_handle ? 0 : callee_parameters, 490 number_of_frames, 491 frame_sizes, 492 frame_pcs, 493 return_type); 494 // On some platforms, we need a way to pass some platform dependent 495 // information to the unpacking code so the skeletal frames come out 496 // correct (initial fp value, unextended sp, ...) 497 info->set_initial_info((intptr_t) array->sender().initial_deoptimization_info()); 498 499 if (array->frames() > 1) { 500 if (VerifyStack && TraceDeoptimization) { 501 ttyLocker ttyl; 502 tty->print_cr("Deoptimizing method containing inlining"); 503 } 504 } 505 506 array->set_unroll_block(info); 507 return info; 508 } 509 510 // Called to cleanup deoptimization data structures in normal case 511 // after unpacking to stack and when stack overflow error occurs 512 void Deoptimization::cleanup_deopt_info(JavaThread *thread, 513 vframeArray *array) { 514 515 // Get array if coming from exception 516 if (array == NULL) { 517 array = thread->vframe_array_head(); 518 } 519 thread->set_vframe_array_head(NULL); 520 521 // Free the previous UnrollBlock 522 vframeArray* old_array = thread->vframe_array_last(); 523 thread->set_vframe_array_last(array); 524 525 if (old_array != NULL) { 526 UnrollBlock* old_info = old_array->unroll_block(); 527 old_array->set_unroll_block(NULL); 528 delete old_info; 529 delete old_array; 530 } 531 532 // Deallocate any resource creating in this routine and any ResourceObjs allocated 533 // inside the vframeArray (StackValueCollections) 534 535 delete thread->deopt_mark(); 536 thread->set_deopt_mark(NULL); 537 thread->set_deopt_nmethod(NULL); 538 539 540 if (JvmtiExport::can_pop_frame()) { 541 #ifndef CC_INTERP 542 // Regardless of whether we entered this routine with the pending 543 // popframe condition bit set, we should always clear it now 544 thread->clear_popframe_condition(); 545 #else 546 // C++ interpreter will clear has_pending_popframe when it enters 547 // with method_resume. For deopt_resume2 we clear it now. 548 if (thread->popframe_forcing_deopt_reexecution()) 549 thread->clear_popframe_condition(); 550 #endif /* CC_INTERP */ 551 } 552 553 // unpack_frames() is called at the end of the deoptimization handler 554 // and (in C2) at the end of the uncommon trap handler. Note this fact 555 // so that an asynchronous stack walker can work again. This counter is 556 // incremented at the beginning of fetch_unroll_info() and (in C2) at 557 // the beginning of uncommon_trap(). 558 thread->dec_in_deopt_handler(); 559 } 560 561 562 // Return BasicType of value being returned 563 JRT_LEAF(BasicType, Deoptimization::unpack_frames(JavaThread* thread, int exec_mode)) 564 565 // We are already active int he special DeoptResourceMark any ResourceObj's we 566 // allocate will be freed at the end of the routine. 567 568 // It is actually ok to allocate handles in a leaf method. It causes no safepoints, 569 // but makes the entry a little slower. There is however a little dance we have to 570 // do in debug mode to get around the NoHandleMark code in the JRT_LEAF macro 571 ResetNoHandleMark rnhm; // No-op in release/product versions 572 HandleMark hm; 573 574 frame stub_frame = thread->last_frame(); 575 576 // Since the frame to unpack is the top frame of this thread, the vframe_array_head 577 // must point to the vframeArray for the unpack frame. 578 vframeArray* array = thread->vframe_array_head(); 579 580 #ifndef PRODUCT 581 if (TraceDeoptimization) { 582 ttyLocker ttyl; 583 tty->print_cr("DEOPT UNPACKING thread " INTPTR_FORMAT " vframeArray " INTPTR_FORMAT " mode %d", thread, array, exec_mode); 584 } 585 #endif 586 Events::log(thread, "DEOPT UNPACKING pc=" INTPTR_FORMAT " sp=" INTPTR_FORMAT " mode %d", 587 stub_frame.pc(), stub_frame.sp(), exec_mode); 588 589 UnrollBlock* info = array->unroll_block(); 590 591 // Unpack the interpreter frames and any adapter frame (c2 only) we might create. 592 array->unpack_to_stack(stub_frame, exec_mode, info->caller_actual_parameters()); 593 594 BasicType bt = info->return_type(); 595 596 // If we have an exception pending, claim that the return type is an oop 597 // so the deopt_blob does not overwrite the exception_oop. 598 599 if (exec_mode == Unpack_exception) 600 bt = T_OBJECT; 601 602 // Cleanup thread deopt data 603 cleanup_deopt_info(thread, array); 604 605 #ifndef PRODUCT 606 if (VerifyStack) { 607 ResourceMark res_mark; 608 609 thread->validate_frame_layout(); 610 611 // Verify that the just-unpacked frames match the interpreter's 612 // notions of expression stack and locals 613 vframeArray* cur_array = thread->vframe_array_last(); 614 RegisterMap rm(thread, false); 615 rm.set_include_argument_oops(false); 616 bool is_top_frame = true; 617 int callee_size_of_parameters = 0; 618 int callee_max_locals = 0; 619 for (int i = 0; i < cur_array->frames(); i++) { 620 vframeArrayElement* el = cur_array->element(i); 621 frame* iframe = el->iframe(); 622 guarantee(iframe->is_interpreted_frame(), "Wrong frame type"); 623 624 // Get the oop map for this bci 625 InterpreterOopMap mask; 626 int cur_invoke_parameter_size = 0; 627 bool try_next_mask = false; 628 int next_mask_expression_stack_size = -1; 629 int top_frame_expression_stack_adjustment = 0; 630 methodHandle mh(thread, iframe->interpreter_frame_method()); 631 OopMapCache::compute_one_oop_map(mh, iframe->interpreter_frame_bci(), &mask); 632 BytecodeStream str(mh); 633 str.set_start(iframe->interpreter_frame_bci()); 634 int max_bci = mh->code_size(); 635 // Get to the next bytecode if possible 636 assert(str.bci() < max_bci, "bci in interpreter frame out of bounds"); 637 // Check to see if we can grab the number of outgoing arguments 638 // at an uncommon trap for an invoke (where the compiler 639 // generates debug info before the invoke has executed) 640 Bytecodes::Code cur_code = str.next(); 641 if (cur_code == Bytecodes::_invokevirtual || 642 cur_code == Bytecodes::_invokespecial || 643 cur_code == Bytecodes::_invokestatic || 644 cur_code == Bytecodes::_invokeinterface || 645 cur_code == Bytecodes::_invokedynamic) { 646 Bytecode_invoke invoke(mh, iframe->interpreter_frame_bci()); 647 Symbol* signature = invoke.signature(); 648 ArgumentSizeComputer asc(signature); 649 cur_invoke_parameter_size = asc.size(); 650 if (invoke.has_receiver()) { 651 // Add in receiver 652 ++cur_invoke_parameter_size; 653 } 654 if (i != 0 && !invoke.is_invokedynamic() && MethodHandles::has_member_arg(invoke.klass(), invoke.name())) { 655 callee_size_of_parameters++; 656 } 657 } 658 if (str.bci() < max_bci) { 659 Bytecodes::Code bc = str.next(); 660 if (bc >= 0) { 661 // The interpreter oop map generator reports results before 662 // the current bytecode has executed except in the case of 663 // calls. It seems to be hard to tell whether the compiler 664 // has emitted debug information matching the "state before" 665 // a given bytecode or the state after, so we try both 666 switch (cur_code) { 667 case Bytecodes::_invokevirtual: 668 case Bytecodes::_invokespecial: 669 case Bytecodes::_invokestatic: 670 case Bytecodes::_invokeinterface: 671 case Bytecodes::_invokedynamic: 672 case Bytecodes::_athrow: 673 break; 674 default: { 675 InterpreterOopMap next_mask; 676 OopMapCache::compute_one_oop_map(mh, str.bci(), &next_mask); 677 next_mask_expression_stack_size = next_mask.expression_stack_size(); 678 // Need to subtract off the size of the result type of 679 // the bytecode because this is not described in the 680 // debug info but returned to the interpreter in the TOS 681 // caching register 682 BasicType bytecode_result_type = Bytecodes::result_type(cur_code); 683 if (bytecode_result_type != T_ILLEGAL) { 684 top_frame_expression_stack_adjustment = type2size[bytecode_result_type]; 685 } 686 assert(top_frame_expression_stack_adjustment >= 0, ""); 687 try_next_mask = true; 688 break; 689 } 690 } 691 } 692 } 693 694 // Verify stack depth and oops in frame 695 // This assertion may be dependent on the platform we're running on and may need modification (tested on x86 and sparc) 696 if (!( 697 /* SPARC */ 698 (iframe->interpreter_frame_expression_stack_size() == mask.expression_stack_size() + callee_size_of_parameters) || 699 /* x86 */ 700 (iframe->interpreter_frame_expression_stack_size() == mask.expression_stack_size() + callee_max_locals) || 701 (try_next_mask && 702 (iframe->interpreter_frame_expression_stack_size() == (next_mask_expression_stack_size - 703 top_frame_expression_stack_adjustment))) || 704 (is_top_frame && (exec_mode == Unpack_exception) && iframe->interpreter_frame_expression_stack_size() == 0) || 705 (is_top_frame && (exec_mode == Unpack_uncommon_trap || exec_mode == Unpack_reexecute) && 706 (iframe->interpreter_frame_expression_stack_size() == mask.expression_stack_size() + cur_invoke_parameter_size)) 707 )) { 708 ttyLocker ttyl; 709 710 // Print out some information that will help us debug the problem 711 tty->print_cr("Wrong number of expression stack elements during deoptimization"); 712 tty->print_cr(" Error occurred while verifying frame %d (0..%d, 0 is topmost)", i, cur_array->frames() - 1); 713 tty->print_cr(" Fabricated interpreter frame had %d expression stack elements", 714 iframe->interpreter_frame_expression_stack_size()); 715 tty->print_cr(" Interpreter oop map had %d expression stack elements", mask.expression_stack_size()); 716 tty->print_cr(" try_next_mask = %d", try_next_mask); 717 tty->print_cr(" next_mask_expression_stack_size = %d", next_mask_expression_stack_size); 718 tty->print_cr(" callee_size_of_parameters = %d", callee_size_of_parameters); 719 tty->print_cr(" callee_max_locals = %d", callee_max_locals); 720 tty->print_cr(" top_frame_expression_stack_adjustment = %d", top_frame_expression_stack_adjustment); 721 tty->print_cr(" exec_mode = %d", exec_mode); 722 tty->print_cr(" cur_invoke_parameter_size = %d", cur_invoke_parameter_size); 723 tty->print_cr(" Thread = " INTPTR_FORMAT ", thread ID = " UINTX_FORMAT, thread, thread->osthread()->thread_id()); 724 tty->print_cr(" Interpreted frames:"); 725 for (int k = 0; k < cur_array->frames(); k++) { 726 vframeArrayElement* el = cur_array->element(k); 727 tty->print_cr(" %s (bci %d)", el->method()->name_and_sig_as_C_string(), el->bci()); 728 } 729 cur_array->print_on_2(tty); 730 guarantee(false, "wrong number of expression stack elements during deopt"); 731 } 732 VerifyOopClosure verify; 733 iframe->oops_interpreted_do(&verify, NULL, &rm, false); 734 callee_size_of_parameters = mh->size_of_parameters(); 735 callee_max_locals = mh->max_locals(); 736 is_top_frame = false; 737 } 738 } 739 #endif /* !PRODUCT */ 740 741 742 return bt; 743 JRT_END 744 745 746 int Deoptimization::deoptimize_dependents() { 747 Threads::deoptimized_wrt_marked_nmethods(); 748 return 0; 749 } 750 751 752 #ifdef COMPILER2 753 bool Deoptimization::realloc_objects(JavaThread* thread, frame* fr, GrowableArray<ScopeValue*>* objects, TRAPS) { 754 Handle pending_exception(thread->pending_exception()); 755 const char* exception_file = thread->exception_file(); 756 int exception_line = thread->exception_line(); 757 thread->clear_pending_exception(); 758 759 for (int i = 0; i < objects->length(); i++) { 760 assert(objects->at(i)->is_object(), "invalid debug information"); 761 ObjectValue* sv = (ObjectValue*) objects->at(i); 762 763 KlassHandle k(java_lang_Class::as_Klass(sv->klass()->as_ConstantOopReadValue()->value()())); 764 oop obj = NULL; 765 766 if (k->oop_is_instance()) { 767 InstanceKlass* ik = InstanceKlass::cast(k()); 768 obj = ik->allocate_instance(CHECK_(false)); 769 } else if (k->oop_is_typeArray()) { 770 TypeArrayKlass* ak = TypeArrayKlass::cast(k()); 771 assert(sv->field_size() % type2size[ak->element_type()] == 0, "non-integral array length"); 772 int len = sv->field_size() / type2size[ak->element_type()]; 773 obj = ak->allocate(len, CHECK_(false)); 774 } else if (k->oop_is_objArray()) { 775 ObjArrayKlass* ak = ObjArrayKlass::cast(k()); 776 obj = ak->allocate(sv->field_size(), CHECK_(false)); 777 } 778 779 assert(obj != NULL, "allocation failed"); 780 assert(sv->value().is_null(), "redundant reallocation"); 781 sv->set_value(obj); 782 } 783 784 if (pending_exception.not_null()) { 785 thread->set_pending_exception(pending_exception(), exception_file, exception_line); 786 } 787 788 return true; 789 } 790 791 // This assumes that the fields are stored in ObjectValue in the same order 792 // they are yielded by do_nonstatic_fields. 793 class FieldReassigner: public FieldClosure { 794 frame* _fr; 795 RegisterMap* _reg_map; 796 ObjectValue* _sv; 797 InstanceKlass* _ik; 798 oop _obj; 799 800 int _i; 801 public: 802 FieldReassigner(frame* fr, RegisterMap* reg_map, ObjectValue* sv, oop obj) : 803 _fr(fr), _reg_map(reg_map), _sv(sv), _obj(obj), _i(0) {} 804 805 int i() const { return _i; } 806 807 808 void do_field(fieldDescriptor* fd) { 809 intptr_t val; 810 StackValue* value = 811 StackValue::create_stack_value(_fr, _reg_map, _sv->field_at(i())); 812 int offset = fd->offset(); 813 switch (fd->field_type()) { 814 case T_OBJECT: case T_ARRAY: 815 assert(value->type() == T_OBJECT, "Agreement."); 816 _obj->obj_field_put(offset, value->get_obj()()); 817 break; 818 819 case T_LONG: case T_DOUBLE: { 820 assert(value->type() == T_INT, "Agreement."); 821 StackValue* low = 822 StackValue::create_stack_value(_fr, _reg_map, _sv->field_at(++_i)); 823 #ifdef _LP64 824 jlong res = (jlong)low->get_int(); 825 #else 826 #ifdef SPARC 827 // For SPARC we have to swap high and low words. 828 jlong res = jlong_from((jint)low->get_int(), (jint)value->get_int()); 829 #else 830 jlong res = jlong_from((jint)value->get_int(), (jint)low->get_int()); 831 #endif //SPARC 832 #endif 833 _obj->long_field_put(offset, res); 834 break; 835 } 836 // Have to cast to INT (32 bits) pointer to avoid little/big-endian problem. 837 case T_INT: case T_FLOAT: // 4 bytes. 838 assert(value->type() == T_INT, "Agreement."); 839 val = value->get_int(); 840 _obj->int_field_put(offset, (jint)*((jint*)&val)); 841 break; 842 843 case T_SHORT: case T_CHAR: // 2 bytes 844 assert(value->type() == T_INT, "Agreement."); 845 val = value->get_int(); 846 _obj->short_field_put(offset, (jshort)*((jint*)&val)); 847 break; 848 849 case T_BOOLEAN: case T_BYTE: // 1 byte 850 assert(value->type() == T_INT, "Agreement."); 851 val = value->get_int(); 852 _obj->bool_field_put(offset, (jboolean)*((jint*)&val)); 853 break; 854 855 default: 856 ShouldNotReachHere(); 857 } 858 _i++; 859 } 860 }; 861 862 // restore elements of an eliminated type array 863 void Deoptimization::reassign_type_array_elements(frame* fr, RegisterMap* reg_map, ObjectValue* sv, typeArrayOop obj, BasicType type) { 864 int index = 0; 865 intptr_t val; 866 867 for (int i = 0; i < sv->field_size(); i++) { 868 StackValue* value = StackValue::create_stack_value(fr, reg_map, sv->field_at(i)); 869 switch(type) { 870 case T_LONG: case T_DOUBLE: { 871 assert(value->type() == T_INT, "Agreement."); 872 StackValue* low = 873 StackValue::create_stack_value(fr, reg_map, sv->field_at(++i)); 874 #ifdef _LP64 875 jlong res = (jlong)low->get_int(); 876 #else 877 #ifdef SPARC 878 // For SPARC we have to swap high and low words. 879 jlong res = jlong_from((jint)low->get_int(), (jint)value->get_int()); 880 #else 881 jlong res = jlong_from((jint)value->get_int(), (jint)low->get_int()); 882 #endif //SPARC 883 #endif 884 obj->long_at_put(index, res); 885 break; 886 } 887 888 // Have to cast to INT (32 bits) pointer to avoid little/big-endian problem. 889 case T_INT: case T_FLOAT: // 4 bytes. 890 assert(value->type() == T_INT, "Agreement."); 891 val = value->get_int(); 892 obj->int_at_put(index, (jint)*((jint*)&val)); 893 break; 894 895 case T_SHORT: case T_CHAR: // 2 bytes 896 assert(value->type() == T_INT, "Agreement."); 897 val = value->get_int(); 898 obj->short_at_put(index, (jshort)*((jint*)&val)); 899 break; 900 901 case T_BOOLEAN: case T_BYTE: // 1 byte 902 assert(value->type() == T_INT, "Agreement."); 903 val = value->get_int(); 904 obj->bool_at_put(index, (jboolean)*((jint*)&val)); 905 break; 906 907 default: 908 ShouldNotReachHere(); 909 } 910 index++; 911 } 912 } 913 914 915 // restore fields of an eliminated object array 916 void Deoptimization::reassign_object_array_elements(frame* fr, RegisterMap* reg_map, ObjectValue* sv, objArrayOop obj) { 917 for (int i = 0; i < sv->field_size(); i++) { 918 StackValue* value = StackValue::create_stack_value(fr, reg_map, sv->field_at(i)); 919 assert(value->type() == T_OBJECT, "object element expected"); 920 obj->obj_at_put(i, value->get_obj()()); 921 } 922 } 923 924 925 // restore fields of all eliminated objects and arrays 926 void Deoptimization::reassign_fields(frame* fr, RegisterMap* reg_map, GrowableArray<ScopeValue*>* objects) { 927 for (int i = 0; i < objects->length(); i++) { 928 ObjectValue* sv = (ObjectValue*) objects->at(i); 929 KlassHandle k(java_lang_Class::as_Klass(sv->klass()->as_ConstantOopReadValue()->value()())); 930 Handle obj = sv->value(); 931 assert(obj.not_null(), "reallocation was missed"); 932 933 if (k->oop_is_instance()) { 934 InstanceKlass* ik = InstanceKlass::cast(k()); 935 FieldReassigner reassign(fr, reg_map, sv, obj()); 936 ik->do_nonstatic_fields(&reassign); 937 } else if (k->oop_is_typeArray()) { 938 TypeArrayKlass* ak = TypeArrayKlass::cast(k()); 939 reassign_type_array_elements(fr, reg_map, sv, (typeArrayOop) obj(), ak->element_type()); 940 } else if (k->oop_is_objArray()) { 941 reassign_object_array_elements(fr, reg_map, sv, (objArrayOop) obj()); 942 } 943 } 944 } 945 946 947 // relock objects for which synchronization was eliminated 948 void Deoptimization::relock_objects(GrowableArray<MonitorInfo*>* monitors, JavaThread* thread) { 949 for (int i = 0; i < monitors->length(); i++) { 950 MonitorInfo* mon_info = monitors->at(i); 951 if (mon_info->eliminated()) { 952 assert(mon_info->owner() != NULL, "reallocation was missed"); 953 Handle obj = Handle(mon_info->owner()); 954 markOop mark = obj->mark(); 955 if (UseBiasedLocking && mark->has_bias_pattern()) { 956 // New allocated objects may have the mark set to anonymously biased. 957 // Also the deoptimized method may called methods with synchronization 958 // where the thread-local object is bias locked to the current thread. 959 assert(mark->is_biased_anonymously() || 960 mark->biased_locker() == thread, "should be locked to current thread"); 961 // Reset mark word to unbiased prototype. 962 markOop unbiased_prototype = markOopDesc::prototype()->set_age(mark->age()); 963 obj->set_mark(unbiased_prototype); 964 } 965 BasicLock* lock = mon_info->lock(); 966 ObjectSynchronizer::slow_enter(obj, lock, thread); 967 } 968 assert(mon_info->owner()->is_locked(), "object must be locked now"); 969 } 970 } 971 972 973 #ifndef PRODUCT 974 // print information about reallocated objects 975 void Deoptimization::print_objects(GrowableArray<ScopeValue*>* objects) { 976 fieldDescriptor fd; 977 978 for (int i = 0; i < objects->length(); i++) { 979 ObjectValue* sv = (ObjectValue*) objects->at(i); 980 KlassHandle k(java_lang_Class::as_Klass(sv->klass()->as_ConstantOopReadValue()->value()())); 981 Handle obj = sv->value(); 982 983 tty->print(" object <" INTPTR_FORMAT "> of type ", (void *)sv->value()()); 984 k->print_value(); 985 tty->print(" allocated (%d bytes)", obj->size() * HeapWordSize); 986 tty->cr(); 987 988 if (Verbose) { 989 k->oop_print_on(obj(), tty); 990 } 991 } 992 } 993 #endif 994 #endif // COMPILER2 995 996 vframeArray* Deoptimization::create_vframeArray(JavaThread* thread, frame fr, RegisterMap *reg_map, GrowableArray<compiledVFrame*>* chunk) { 997 Events::log(thread, "DEOPT PACKING pc=" INTPTR_FORMAT " sp=" INTPTR_FORMAT, fr.pc(), fr.sp()); 998 999 #ifndef PRODUCT 1000 if (TraceDeoptimization) { 1001 ttyLocker ttyl; 1002 tty->print("DEOPT PACKING thread " INTPTR_FORMAT " ", thread); 1003 fr.print_on(tty); 1004 tty->print_cr(" Virtual frames (innermost first):"); 1005 for (int index = 0; index < chunk->length(); index++) { 1006 compiledVFrame* vf = chunk->at(index); 1007 tty->print(" %2d - ", index); 1008 vf->print_value(); 1009 int bci = chunk->at(index)->raw_bci(); 1010 const char* code_name; 1011 if (bci == SynchronizationEntryBCI) { 1012 code_name = "sync entry"; 1013 } else { 1014 Bytecodes::Code code = vf->method()->code_at(bci); 1015 code_name = Bytecodes::name(code); 1016 } 1017 tty->print(" - %s", code_name); 1018 tty->print_cr(" @ bci %d ", bci); 1019 if (Verbose) { 1020 vf->print(); 1021 tty->cr(); 1022 } 1023 } 1024 } 1025 #endif 1026 1027 // Register map for next frame (used for stack crawl). We capture 1028 // the state of the deopt'ing frame's caller. Thus if we need to 1029 // stuff a C2I adapter we can properly fill in the callee-save 1030 // register locations. 1031 frame caller = fr.sender(reg_map); 1032 int frame_size = caller.sp() - fr.sp(); 1033 1034 frame sender = caller; 1035 1036 // Since the Java thread being deoptimized will eventually adjust it's own stack, 1037 // the vframeArray containing the unpacking information is allocated in the C heap. 1038 // For Compiler1, the caller of the deoptimized frame is saved for use by unpack_frames(). 1039 vframeArray* array = vframeArray::allocate(thread, frame_size, chunk, reg_map, sender, caller, fr); 1040 1041 // Compare the vframeArray to the collected vframes 1042 assert(array->structural_compare(thread, chunk), "just checking"); 1043 1044 #ifndef PRODUCT 1045 if (TraceDeoptimization) { 1046 ttyLocker ttyl; 1047 tty->print_cr(" Created vframeArray " INTPTR_FORMAT, array); 1048 } 1049 #endif // PRODUCT 1050 1051 return array; 1052 } 1053 1054 1055 static void collect_monitors(compiledVFrame* cvf, GrowableArray<Handle>* objects_to_revoke) { 1056 GrowableArray<MonitorInfo*>* monitors = cvf->monitors(); 1057 for (int i = 0; i < monitors->length(); i++) { 1058 MonitorInfo* mon_info = monitors->at(i); 1059 if (!mon_info->eliminated() && mon_info->owner() != NULL) { 1060 objects_to_revoke->append(Handle(mon_info->owner())); 1061 } 1062 } 1063 } 1064 1065 1066 void Deoptimization::revoke_biases_of_monitors(JavaThread* thread, frame fr, RegisterMap* map) { 1067 if (!UseBiasedLocking) { 1068 return; 1069 } 1070 1071 GrowableArray<Handle>* objects_to_revoke = new GrowableArray<Handle>(); 1072 1073 // Unfortunately we don't have a RegisterMap available in most of 1074 // the places we want to call this routine so we need to walk the 1075 // stack again to update the register map. 1076 if (map == NULL || !map->update_map()) { 1077 StackFrameStream sfs(thread, true); 1078 bool found = false; 1079 while (!found && !sfs.is_done()) { 1080 frame* cur = sfs.current(); 1081 sfs.next(); 1082 found = cur->id() == fr.id(); 1083 } 1084 assert(found, "frame to be deoptimized not found on target thread's stack"); 1085 map = sfs.register_map(); 1086 } 1087 1088 vframe* vf = vframe::new_vframe(&fr, map, thread); 1089 compiledVFrame* cvf = compiledVFrame::cast(vf); 1090 // Revoke monitors' biases in all scopes 1091 while (!cvf->is_top()) { 1092 collect_monitors(cvf, objects_to_revoke); 1093 cvf = compiledVFrame::cast(cvf->sender()); 1094 } 1095 collect_monitors(cvf, objects_to_revoke); 1096 1097 if (SafepointSynchronize::is_at_safepoint()) { 1098 BiasedLocking::revoke_at_safepoint(objects_to_revoke); 1099 } else { 1100 BiasedLocking::revoke(objects_to_revoke); 1101 } 1102 } 1103 1104 1105 void Deoptimization::revoke_biases_of_monitors(CodeBlob* cb) { 1106 if (!UseBiasedLocking) { 1107 return; 1108 } 1109 1110 assert(SafepointSynchronize::is_at_safepoint(), "must only be called from safepoint"); 1111 GrowableArray<Handle>* objects_to_revoke = new GrowableArray<Handle>(); 1112 for (JavaThread* jt = Threads::first(); jt != NULL ; jt = jt->next()) { 1113 if (jt->has_last_Java_frame()) { 1114 StackFrameStream sfs(jt, true); 1115 while (!sfs.is_done()) { 1116 frame* cur = sfs.current(); 1117 if (cb->contains(cur->pc())) { 1118 vframe* vf = vframe::new_vframe(cur, sfs.register_map(), jt); 1119 compiledVFrame* cvf = compiledVFrame::cast(vf); 1120 // Revoke monitors' biases in all scopes 1121 while (!cvf->is_top()) { 1122 collect_monitors(cvf, objects_to_revoke); 1123 cvf = compiledVFrame::cast(cvf->sender()); 1124 } 1125 collect_monitors(cvf, objects_to_revoke); 1126 } 1127 sfs.next(); 1128 } 1129 } 1130 } 1131 BiasedLocking::revoke_at_safepoint(objects_to_revoke); 1132 } 1133 1134 1135 void Deoptimization::deoptimize_single_frame(JavaThread* thread, frame fr) { 1136 assert(fr.can_be_deoptimized(), "checking frame type"); 1137 1138 gather_statistics(Reason_constraint, Action_none, Bytecodes::_illegal); 1139 1140 // Patch the nmethod so that when execution returns to it we will 1141 // deopt the execution state and return to the interpreter. 1142 fr.deoptimize(thread); 1143 } 1144 1145 void Deoptimization::deoptimize(JavaThread* thread, frame fr, RegisterMap *map) { 1146 // Deoptimize only if the frame comes from compile code. 1147 // Do not deoptimize the frame which is already patched 1148 // during the execution of the loops below. 1149 if (!fr.is_compiled_frame() || fr.is_deoptimized_frame()) { 1150 return; 1151 } 1152 ResourceMark rm; 1153 DeoptimizationMarker dm; 1154 if (UseBiasedLocking) { 1155 revoke_biases_of_monitors(thread, fr, map); 1156 } 1157 deoptimize_single_frame(thread, fr); 1158 1159 } 1160 1161 1162 void Deoptimization::deoptimize_frame_internal(JavaThread* thread, intptr_t* id) { 1163 assert(thread == Thread::current() || SafepointSynchronize::is_at_safepoint(), 1164 "can only deoptimize other thread at a safepoint"); 1165 // Compute frame and register map based on thread and sp. 1166 RegisterMap reg_map(thread, UseBiasedLocking); 1167 frame fr = thread->last_frame(); 1168 while (fr.id() != id) { 1169 fr = fr.sender(®_map); 1170 } 1171 deoptimize(thread, fr, ®_map); 1172 } 1173 1174 1175 void Deoptimization::deoptimize_frame(JavaThread* thread, intptr_t* id) { 1176 if (thread == Thread::current()) { 1177 Deoptimization::deoptimize_frame_internal(thread, id); 1178 } else { 1179 VM_DeoptimizeFrame deopt(thread, id); 1180 VMThread::execute(&deopt); 1181 } 1182 } 1183 1184 1185 // JVMTI PopFrame support 1186 JRT_LEAF(void, Deoptimization::popframe_preserve_args(JavaThread* thread, int bytes_to_save, void* start_address)) 1187 { 1188 thread->popframe_preserve_args(in_ByteSize(bytes_to_save), start_address); 1189 } 1190 JRT_END 1191 1192 1193 #if defined(COMPILER2) || defined(SHARK) 1194 void Deoptimization::load_class_by_index(constantPoolHandle constant_pool, int index, TRAPS) { 1195 // in case of an unresolved klass entry, load the class. 1196 if (constant_pool->tag_at(index).is_unresolved_klass()) { 1197 Klass* tk = constant_pool->klass_at(index, CHECK); 1198 return; 1199 } 1200 1201 if (!constant_pool->tag_at(index).is_symbol()) return; 1202 1203 Handle class_loader (THREAD, constant_pool->pool_holder()->class_loader()); 1204 Symbol* symbol = constant_pool->symbol_at(index); 1205 1206 // class name? 1207 if (symbol->byte_at(0) != '(') { 1208 Handle protection_domain (THREAD, constant_pool->pool_holder()->protection_domain()); 1209 SystemDictionary::resolve_or_null(symbol, class_loader, protection_domain, CHECK); 1210 return; 1211 } 1212 1213 // then it must be a signature! 1214 ResourceMark rm(THREAD); 1215 for (SignatureStream ss(symbol); !ss.is_done(); ss.next()) { 1216 if (ss.is_object()) { 1217 Symbol* class_name = ss.as_symbol(CHECK); 1218 Handle protection_domain (THREAD, constant_pool->pool_holder()->protection_domain()); 1219 SystemDictionary::resolve_or_null(class_name, class_loader, protection_domain, CHECK); 1220 } 1221 } 1222 } 1223 1224 1225 void Deoptimization::load_class_by_index(constantPoolHandle constant_pool, int index) { 1226 EXCEPTION_MARK; 1227 load_class_by_index(constant_pool, index, THREAD); 1228 if (HAS_PENDING_EXCEPTION) { 1229 // Exception happened during classloading. We ignore the exception here, since it 1230 // is going to be rethrown since the current activation is going to be deoptimized and 1231 // the interpreter will re-execute the bytecode. 1232 CLEAR_PENDING_EXCEPTION; 1233 // Class loading called java code which may have caused a stack 1234 // overflow. If the exception was thrown right before the return 1235 // to the runtime the stack is no longer guarded. Reguard the 1236 // stack otherwise if we return to the uncommon trap blob and the 1237 // stack bang causes a stack overflow we crash. 1238 assert(THREAD->is_Java_thread(), "only a java thread can be here"); 1239 JavaThread* thread = (JavaThread*)THREAD; 1240 bool guard_pages_enabled = thread->stack_yellow_zone_enabled(); 1241 if (!guard_pages_enabled) guard_pages_enabled = thread->reguard_stack(); 1242 assert(guard_pages_enabled, "stack banging in uncommon trap blob may cause crash"); 1243 } 1244 } 1245 1246 JRT_ENTRY(void, Deoptimization::uncommon_trap_inner(JavaThread* thread, jint trap_request)) { 1247 HandleMark hm; 1248 1249 // uncommon_trap() is called at the beginning of the uncommon trap 1250 // handler. Note this fact before we start generating temporary frames 1251 // that can confuse an asynchronous stack walker. This counter is 1252 // decremented at the end of unpack_frames(). 1253 thread->inc_in_deopt_handler(); 1254 1255 // We need to update the map if we have biased locking. 1256 RegisterMap reg_map(thread, UseBiasedLocking); 1257 frame stub_frame = thread->last_frame(); 1258 frame fr = stub_frame.sender(®_map); 1259 // Make sure the calling nmethod is not getting deoptimized and removed 1260 // before we are done with it. 1261 nmethodLocker nl(fr.pc()); 1262 1263 // Log a message 1264 Events::log(thread, "Uncommon trap: trap_request=" PTR32_FORMAT " fr.pc=" INTPTR_FORMAT, 1265 trap_request, fr.pc()); 1266 1267 { 1268 ResourceMark rm; 1269 1270 // Revoke biases of any monitors in the frame to ensure we can migrate them 1271 revoke_biases_of_monitors(thread, fr, ®_map); 1272 1273 DeoptReason reason = trap_request_reason(trap_request); 1274 DeoptAction action = trap_request_action(trap_request); 1275 jint unloaded_class_index = trap_request_index(trap_request); // CP idx or -1 1276 1277 vframe* vf = vframe::new_vframe(&fr, ®_map, thread); 1278 compiledVFrame* cvf = compiledVFrame::cast(vf); 1279 1280 nmethod* nm = cvf->code(); 1281 1282 ScopeDesc* trap_scope = cvf->scope(); 1283 methodHandle trap_method = trap_scope->method(); 1284 int trap_bci = trap_scope->bci(); 1285 Bytecodes::Code trap_bc = trap_method->java_code_at(trap_bci); 1286 1287 // Record this event in the histogram. 1288 gather_statistics(reason, action, trap_bc); 1289 1290 // Ensure that we can record deopt. history: 1291 // Need MDO to record RTM code generation state. 1292 bool create_if_missing = ProfileTraps RTM_OPT_ONLY( || UseRTMLocking ); 1293 1294 MethodData* trap_mdo = 1295 get_method_data(thread, trap_method, create_if_missing); 1296 1297 // Log a message 1298 Events::log_deopt_message(thread, "Uncommon trap: reason=%s action=%s pc=" INTPTR_FORMAT " method=%s @ %d", 1299 trap_reason_name(reason), trap_action_name(action), fr.pc(), 1300 trap_method->name_and_sig_as_C_string(), trap_bci); 1301 1302 // Print a bunch of diagnostics, if requested. 1303 if (TraceDeoptimization || LogCompilation) { 1304 ResourceMark rm; 1305 ttyLocker ttyl; 1306 char buf[100]; 1307 if (xtty != NULL) { 1308 xtty->begin_head("uncommon_trap thread='" UINTX_FORMAT"' %s", 1309 os::current_thread_id(), 1310 format_trap_request(buf, sizeof(buf), trap_request)); 1311 nm->log_identity(xtty); 1312 } 1313 Symbol* class_name = NULL; 1314 bool unresolved = false; 1315 if (unloaded_class_index >= 0) { 1316 constantPoolHandle constants (THREAD, trap_method->constants()); 1317 if (constants->tag_at(unloaded_class_index).is_unresolved_klass()) { 1318 class_name = constants->klass_name_at(unloaded_class_index); 1319 unresolved = true; 1320 if (xtty != NULL) 1321 xtty->print(" unresolved='1'"); 1322 } else if (constants->tag_at(unloaded_class_index).is_symbol()) { 1323 class_name = constants->symbol_at(unloaded_class_index); 1324 } 1325 if (xtty != NULL) 1326 xtty->name(class_name); 1327 } 1328 if (xtty != NULL && trap_mdo != NULL) { 1329 // Dump the relevant MDO state. 1330 // This is the deopt count for the current reason, any previous 1331 // reasons or recompiles seen at this point. 1332 int dcnt = trap_mdo->trap_count(reason); 1333 if (dcnt != 0) 1334 xtty->print(" count='%d'", dcnt); 1335 ProfileData* pdata = trap_mdo->bci_to_data(trap_bci); 1336 int dos = (pdata == NULL)? 0: pdata->trap_state(); 1337 if (dos != 0) { 1338 xtty->print(" state='%s'", format_trap_state(buf, sizeof(buf), dos)); 1339 if (trap_state_is_recompiled(dos)) { 1340 int recnt2 = trap_mdo->overflow_recompile_count(); 1341 if (recnt2 != 0) 1342 xtty->print(" recompiles2='%d'", recnt2); 1343 } 1344 } 1345 } 1346 if (xtty != NULL) { 1347 xtty->stamp(); 1348 xtty->end_head(); 1349 } 1350 if (TraceDeoptimization) { // make noise on the tty 1351 tty->print("Uncommon trap occurred in"); 1352 nm->method()->print_short_name(tty); 1353 tty->print(" (@" INTPTR_FORMAT ") thread=" UINTX_FORMAT " reason=%s action=%s unloaded_class_index=%d", 1354 fr.pc(), 1355 os::current_thread_id(), 1356 trap_reason_name(reason), 1357 trap_action_name(action), 1358 unloaded_class_index); 1359 if (class_name != NULL) { 1360 tty->print(unresolved ? " unresolved class: " : " symbol: "); 1361 class_name->print_symbol_on(tty); 1362 } 1363 tty->cr(); 1364 } 1365 if (xtty != NULL) { 1366 // Log the precise location of the trap. 1367 for (ScopeDesc* sd = trap_scope; ; sd = sd->sender()) { 1368 xtty->begin_elem("jvms bci='%d'", sd->bci()); 1369 xtty->method(sd->method()); 1370 xtty->end_elem(); 1371 if (sd->is_top()) break; 1372 } 1373 xtty->tail("uncommon_trap"); 1374 } 1375 } 1376 // (End diagnostic printout.) 1377 1378 // Load class if necessary 1379 if (unloaded_class_index >= 0) { 1380 constantPoolHandle constants(THREAD, trap_method->constants()); 1381 load_class_by_index(constants, unloaded_class_index); 1382 } 1383 1384 // Flush the nmethod if necessary and desirable. 1385 // 1386 // We need to avoid situations where we are re-flushing the nmethod 1387 // because of a hot deoptimization site. Repeated flushes at the same 1388 // point need to be detected by the compiler and avoided. If the compiler 1389 // cannot avoid them (or has a bug and "refuses" to avoid them), this 1390 // module must take measures to avoid an infinite cycle of recompilation 1391 // and deoptimization. There are several such measures: 1392 // 1393 // 1. If a recompilation is ordered a second time at some site X 1394 // and for the same reason R, the action is adjusted to 'reinterpret', 1395 // to give the interpreter time to exercise the method more thoroughly. 1396 // If this happens, the method's overflow_recompile_count is incremented. 1397 // 1398 // 2. If the compiler fails to reduce the deoptimization rate, then 1399 // the method's overflow_recompile_count will begin to exceed the set 1400 // limit PerBytecodeRecompilationCutoff. If this happens, the action 1401 // is adjusted to 'make_not_compilable', and the method is abandoned 1402 // to the interpreter. This is a performance hit for hot methods, 1403 // but is better than a disastrous infinite cycle of recompilations. 1404 // (Actually, only the method containing the site X is abandoned.) 1405 // 1406 // 3. In parallel with the previous measures, if the total number of 1407 // recompilations of a method exceeds the much larger set limit 1408 // PerMethodRecompilationCutoff, the method is abandoned. 1409 // This should only happen if the method is very large and has 1410 // many "lukewarm" deoptimizations. The code which enforces this 1411 // limit is elsewhere (class nmethod, class Method). 1412 // 1413 // Note that the per-BCI 'is_recompiled' bit gives the compiler one chance 1414 // to recompile at each bytecode independently of the per-BCI cutoff. 1415 // 1416 // The decision to update code is up to the compiler, and is encoded 1417 // in the Action_xxx code. If the compiler requests Action_none 1418 // no trap state is changed, no compiled code is changed, and the 1419 // computation suffers along in the interpreter. 1420 // 1421 // The other action codes specify various tactics for decompilation 1422 // and recompilation. Action_maybe_recompile is the loosest, and 1423 // allows the compiled code to stay around until enough traps are seen, 1424 // and until the compiler gets around to recompiling the trapping method. 1425 // 1426 // The other actions cause immediate removal of the present code. 1427 1428 bool update_trap_state = true; 1429 bool make_not_entrant = false; 1430 bool make_not_compilable = false; 1431 bool reprofile = false; 1432 switch (action) { 1433 case Action_none: 1434 // Keep the old code. 1435 update_trap_state = false; 1436 break; 1437 case Action_maybe_recompile: 1438 // Do not need to invalidate the present code, but we can 1439 // initiate another 1440 // Start compiler without (necessarily) invalidating the nmethod. 1441 // The system will tolerate the old code, but new code should be 1442 // generated when possible. 1443 break; 1444 case Action_reinterpret: 1445 // Go back into the interpreter for a while, and then consider 1446 // recompiling form scratch. 1447 make_not_entrant = true; 1448 // Reset invocation counter for outer most method. 1449 // This will allow the interpreter to exercise the bytecodes 1450 // for a while before recompiling. 1451 // By contrast, Action_make_not_entrant is immediate. 1452 // 1453 // Note that the compiler will track null_check, null_assert, 1454 // range_check, and class_check events and log them as if they 1455 // had been traps taken from compiled code. This will update 1456 // the MDO trap history so that the next compilation will 1457 // properly detect hot trap sites. 1458 reprofile = true; 1459 break; 1460 case Action_make_not_entrant: 1461 // Request immediate recompilation, and get rid of the old code. 1462 // Make them not entrant, so next time they are called they get 1463 // recompiled. Unloaded classes are loaded now so recompile before next 1464 // time they are called. Same for uninitialized. The interpreter will 1465 // link the missing class, if any. 1466 make_not_entrant = true; 1467 break; 1468 case Action_make_not_compilable: 1469 // Give up on compiling this method at all. 1470 make_not_entrant = true; 1471 make_not_compilable = true; 1472 break; 1473 default: 1474 ShouldNotReachHere(); 1475 } 1476 1477 // Setting +ProfileTraps fixes the following, on all platforms: 1478 // 4852688: ProfileInterpreter is off by default for ia64. The result is 1479 // infinite heroic-opt-uncommon-trap/deopt/recompile cycles, since the 1480 // recompile relies on a MethodData* to record heroic opt failures. 1481 1482 // Whether the interpreter is producing MDO data or not, we also need 1483 // to use the MDO to detect hot deoptimization points and control 1484 // aggressive optimization. 1485 bool inc_recompile_count = false; 1486 ProfileData* pdata = NULL; 1487 if (ProfileTraps && update_trap_state && trap_mdo != NULL) { 1488 assert(trap_mdo == get_method_data(thread, trap_method, false), "sanity"); 1489 uint this_trap_count = 0; 1490 bool maybe_prior_trap = false; 1491 bool maybe_prior_recompile = false; 1492 pdata = query_update_method_data(trap_mdo, trap_bci, reason, 1493 nm->method(), 1494 //outputs: 1495 this_trap_count, 1496 maybe_prior_trap, 1497 maybe_prior_recompile); 1498 // Because the interpreter also counts null, div0, range, and class 1499 // checks, these traps from compiled code are double-counted. 1500 // This is harmless; it just means that the PerXTrapLimit values 1501 // are in effect a little smaller than they look. 1502 1503 DeoptReason per_bc_reason = reason_recorded_per_bytecode_if_any(reason); 1504 if (per_bc_reason != Reason_none) { 1505 // Now take action based on the partially known per-BCI history. 1506 if (maybe_prior_trap 1507 && this_trap_count >= (uint)PerBytecodeTrapLimit) { 1508 // If there are too many traps at this BCI, force a recompile. 1509 // This will allow the compiler to see the limit overflow, and 1510 // take corrective action, if possible. The compiler generally 1511 // does not use the exact PerBytecodeTrapLimit value, but instead 1512 // changes its tactics if it sees any traps at all. This provides 1513 // a little hysteresis, delaying a recompile until a trap happens 1514 // several times. 1515 // 1516 // Actually, since there is only one bit of counter per BCI, 1517 // the possible per-BCI counts are {0,1,(per-method count)}. 1518 // This produces accurate results if in fact there is only 1519 // one hot trap site, but begins to get fuzzy if there are 1520 // many sites. For example, if there are ten sites each 1521 // trapping two or more times, they each get the blame for 1522 // all of their traps. 1523 make_not_entrant = true; 1524 } 1525 1526 // Detect repeated recompilation at the same BCI, and enforce a limit. 1527 if (make_not_entrant && maybe_prior_recompile) { 1528 // More than one recompile at this point. 1529 inc_recompile_count = maybe_prior_trap; 1530 } 1531 } else { 1532 // For reasons which are not recorded per-bytecode, we simply 1533 // force recompiles unconditionally. 1534 // (Note that PerMethodRecompilationCutoff is enforced elsewhere.) 1535 make_not_entrant = true; 1536 } 1537 1538 // Go back to the compiler if there are too many traps in this method. 1539 if (this_trap_count >= per_method_trap_limit(reason)) { 1540 // If there are too many traps in this method, force a recompile. 1541 // This will allow the compiler to see the limit overflow, and 1542 // take corrective action, if possible. 1543 // (This condition is an unlikely backstop only, because the 1544 // PerBytecodeTrapLimit is more likely to take effect first, 1545 // if it is applicable.) 1546 make_not_entrant = true; 1547 } 1548 1549 // Here's more hysteresis: If there has been a recompile at 1550 // this trap point already, run the method in the interpreter 1551 // for a while to exercise it more thoroughly. 1552 if (make_not_entrant && maybe_prior_recompile && maybe_prior_trap) { 1553 reprofile = true; 1554 } 1555 1556 } 1557 1558 // Take requested actions on the method: 1559 1560 // Recompile 1561 if (make_not_entrant) { 1562 if (!nm->make_not_entrant()) { 1563 return; // the call did not change nmethod's state 1564 } 1565 1566 if (pdata != NULL) { 1567 // Record the recompilation event, if any. 1568 int tstate0 = pdata->trap_state(); 1569 int tstate1 = trap_state_set_recompiled(tstate0, true); 1570 if (tstate1 != tstate0) 1571 pdata->set_trap_state(tstate1); 1572 } 1573 1574 #if INCLUDE_RTM_OPT 1575 // Restart collecting RTM locking abort statistic if the method 1576 // is recompiled for a reason other than RTM state change. 1577 // Assume that in new recompiled code the statistic could be different, 1578 // for example, due to different inlining. 1579 if ((reason != Reason_rtm_state_change) && (trap_mdo != NULL) && 1580 UseRTMDeopt && (nm->rtm_state() != ProfileRTM)) { 1581 trap_mdo->atomic_set_rtm_state(ProfileRTM); 1582 } 1583 #endif 1584 } 1585 1586 if (inc_recompile_count) { 1587 trap_mdo->inc_overflow_recompile_count(); 1588 if ((uint)trap_mdo->overflow_recompile_count() > 1589 (uint)PerBytecodeRecompilationCutoff) { 1590 // Give up on the method containing the bad BCI. 1591 if (trap_method() == nm->method()) { 1592 make_not_compilable = true; 1593 } else { 1594 trap_method->set_not_compilable(CompLevel_full_optimization, true, "overflow_recompile_count > PerBytecodeRecompilationCutoff"); 1595 // But give grace to the enclosing nm->method(). 1596 } 1597 } 1598 } 1599 1600 // Reprofile 1601 if (reprofile) { 1602 CompilationPolicy::policy()->reprofile(trap_scope, nm->is_osr_method()); 1603 } 1604 1605 // Give up compiling 1606 if (make_not_compilable && !nm->method()->is_not_compilable(CompLevel_full_optimization)) { 1607 assert(make_not_entrant, "consistent"); 1608 nm->method()->set_not_compilable(CompLevel_full_optimization); 1609 } 1610 1611 } // Free marked resources 1612 1613 } 1614 JRT_END 1615 1616 MethodData* 1617 Deoptimization::get_method_data(JavaThread* thread, methodHandle m, 1618 bool create_if_missing) { 1619 Thread* THREAD = thread; 1620 MethodData* mdo = m()->method_data(); 1621 if (mdo == NULL && create_if_missing && !HAS_PENDING_EXCEPTION) { 1622 // Build an MDO. Ignore errors like OutOfMemory; 1623 // that simply means we won't have an MDO to update. 1624 Method::build_interpreter_method_data(m, THREAD); 1625 if (HAS_PENDING_EXCEPTION) { 1626 assert((PENDING_EXCEPTION->is_a(SystemDictionary::OutOfMemoryError_klass())), "we expect only an OOM error here"); 1627 CLEAR_PENDING_EXCEPTION; 1628 } 1629 mdo = m()->method_data(); 1630 } 1631 return mdo; 1632 } 1633 1634 ProfileData* 1635 Deoptimization::query_update_method_data(MethodData* trap_mdo, 1636 int trap_bci, 1637 Deoptimization::DeoptReason reason, 1638 Method* compiled_method, 1639 //outputs: 1640 uint& ret_this_trap_count, 1641 bool& ret_maybe_prior_trap, 1642 bool& ret_maybe_prior_recompile) { 1643 uint prior_trap_count = trap_mdo->trap_count(reason); 1644 uint this_trap_count = trap_mdo->inc_trap_count(reason); 1645 1646 // If the runtime cannot find a place to store trap history, 1647 // it is estimated based on the general condition of the method. 1648 // If the method has ever been recompiled, or has ever incurred 1649 // a trap with the present reason , then this BCI is assumed 1650 // (pessimistically) to be the culprit. 1651 bool maybe_prior_trap = (prior_trap_count != 0); 1652 bool maybe_prior_recompile = (trap_mdo->decompile_count() != 0); 1653 ProfileData* pdata = NULL; 1654 1655 1656 // For reasons which are recorded per bytecode, we check per-BCI data. 1657 DeoptReason per_bc_reason = reason_recorded_per_bytecode_if_any(reason); 1658 if (per_bc_reason != Reason_none) { 1659 // Find the profile data for this BCI. If there isn't one, 1660 // try to allocate one from the MDO's set of spares. 1661 // This will let us detect a repeated trap at this point. 1662 pdata = trap_mdo->allocate_bci_to_data(trap_bci, reason_is_speculate(reason) ? compiled_method : NULL); 1663 1664 if (pdata != NULL) { 1665 if (reason_is_speculate(reason) && !pdata->is_SpeculativeTrapData()) { 1666 if (LogCompilation && xtty != NULL) { 1667 ttyLocker ttyl; 1668 // no more room for speculative traps in this MDO 1669 xtty->elem("speculative_traps_oom"); 1670 } 1671 } 1672 // Query the trap state of this profile datum. 1673 int tstate0 = pdata->trap_state(); 1674 if (!trap_state_has_reason(tstate0, per_bc_reason)) 1675 maybe_prior_trap = false; 1676 if (!trap_state_is_recompiled(tstate0)) 1677 maybe_prior_recompile = false; 1678 1679 // Update the trap state of this profile datum. 1680 int tstate1 = tstate0; 1681 // Record the reason. 1682 tstate1 = trap_state_add_reason(tstate1, per_bc_reason); 1683 // Store the updated state on the MDO, for next time. 1684 if (tstate1 != tstate0) 1685 pdata->set_trap_state(tstate1); 1686 } else { 1687 if (LogCompilation && xtty != NULL) { 1688 ttyLocker ttyl; 1689 // Missing MDP? Leave a small complaint in the log. 1690 xtty->elem("missing_mdp bci='%d'", trap_bci); 1691 } 1692 } 1693 } 1694 1695 // Return results: 1696 ret_this_trap_count = this_trap_count; 1697 ret_maybe_prior_trap = maybe_prior_trap; 1698 ret_maybe_prior_recompile = maybe_prior_recompile; 1699 return pdata; 1700 } 1701 1702 void 1703 Deoptimization::update_method_data_from_interpreter(MethodData* trap_mdo, int trap_bci, int reason) { 1704 ResourceMark rm; 1705 // Ignored outputs: 1706 uint ignore_this_trap_count; 1707 bool ignore_maybe_prior_trap; 1708 bool ignore_maybe_prior_recompile; 1709 assert(!reason_is_speculate(reason), "reason speculate only used by compiler"); 1710 query_update_method_data(trap_mdo, trap_bci, 1711 (DeoptReason)reason, 1712 NULL, 1713 ignore_this_trap_count, 1714 ignore_maybe_prior_trap, 1715 ignore_maybe_prior_recompile); 1716 } 1717 1718 Deoptimization::UnrollBlock* Deoptimization::uncommon_trap(JavaThread* thread, jint trap_request) { 1719 1720 // Still in Java no safepoints 1721 { 1722 // This enters VM and may safepoint 1723 uncommon_trap_inner(thread, trap_request); 1724 } 1725 return fetch_unroll_info_helper(thread); 1726 } 1727 1728 // Local derived constants. 1729 // Further breakdown of DataLayout::trap_state, as promised by DataLayout. 1730 const int DS_REASON_MASK = DataLayout::trap_mask >> 1; 1731 const int DS_RECOMPILE_BIT = DataLayout::trap_mask - DS_REASON_MASK; 1732 1733 //---------------------------trap_state_reason--------------------------------- 1734 Deoptimization::DeoptReason 1735 Deoptimization::trap_state_reason(int trap_state) { 1736 // This assert provides the link between the width of DataLayout::trap_bits 1737 // and the encoding of "recorded" reasons. It ensures there are enough 1738 // bits to store all needed reasons in the per-BCI MDO profile. 1739 assert(DS_REASON_MASK >= Reason_RECORDED_LIMIT, "enough bits"); 1740 int recompile_bit = (trap_state & DS_RECOMPILE_BIT); 1741 trap_state -= recompile_bit; 1742 if (trap_state == DS_REASON_MASK) { 1743 return Reason_many; 1744 } else { 1745 assert((int)Reason_none == 0, "state=0 => Reason_none"); 1746 return (DeoptReason)trap_state; 1747 } 1748 } 1749 //-------------------------trap_state_has_reason------------------------------- 1750 int Deoptimization::trap_state_has_reason(int trap_state, int reason) { 1751 assert(reason_is_recorded_per_bytecode((DeoptReason)reason), "valid reason"); 1752 assert(DS_REASON_MASK >= Reason_RECORDED_LIMIT, "enough bits"); 1753 int recompile_bit = (trap_state & DS_RECOMPILE_BIT); 1754 trap_state -= recompile_bit; 1755 if (trap_state == DS_REASON_MASK) { 1756 return -1; // true, unspecifically (bottom of state lattice) 1757 } else if (trap_state == reason) { 1758 return 1; // true, definitely 1759 } else if (trap_state == 0) { 1760 return 0; // false, definitely (top of state lattice) 1761 } else { 1762 return 0; // false, definitely 1763 } 1764 } 1765 //-------------------------trap_state_add_reason------------------------------- 1766 int Deoptimization::trap_state_add_reason(int trap_state, int reason) { 1767 assert(reason_is_recorded_per_bytecode((DeoptReason)reason) || reason == Reason_many, "valid reason"); 1768 int recompile_bit = (trap_state & DS_RECOMPILE_BIT); 1769 trap_state -= recompile_bit; 1770 if (trap_state == DS_REASON_MASK) { 1771 return trap_state + recompile_bit; // already at state lattice bottom 1772 } else if (trap_state == reason) { 1773 return trap_state + recompile_bit; // the condition is already true 1774 } else if (trap_state == 0) { 1775 return reason + recompile_bit; // no condition has yet been true 1776 } else { 1777 return DS_REASON_MASK + recompile_bit; // fall to state lattice bottom 1778 } 1779 } 1780 //-----------------------trap_state_is_recompiled------------------------------ 1781 bool Deoptimization::trap_state_is_recompiled(int trap_state) { 1782 return (trap_state & DS_RECOMPILE_BIT) != 0; 1783 } 1784 //-----------------------trap_state_set_recompiled----------------------------- 1785 int Deoptimization::trap_state_set_recompiled(int trap_state, bool z) { 1786 if (z) return trap_state | DS_RECOMPILE_BIT; 1787 else return trap_state & ~DS_RECOMPILE_BIT; 1788 } 1789 //---------------------------format_trap_state--------------------------------- 1790 // This is used for debugging and diagnostics, including LogFile output. 1791 const char* Deoptimization::format_trap_state(char* buf, size_t buflen, 1792 int trap_state) { 1793 DeoptReason reason = trap_state_reason(trap_state); 1794 bool recomp_flag = trap_state_is_recompiled(trap_state); 1795 // Re-encode the state from its decoded components. 1796 int decoded_state = 0; 1797 if (reason_is_recorded_per_bytecode(reason) || reason == Reason_many) 1798 decoded_state = trap_state_add_reason(decoded_state, reason); 1799 if (recomp_flag) 1800 decoded_state = trap_state_set_recompiled(decoded_state, recomp_flag); 1801 // If the state re-encodes properly, format it symbolically. 1802 // Because this routine is used for debugging and diagnostics, 1803 // be robust even if the state is a strange value. 1804 size_t len; 1805 if (decoded_state != trap_state) { 1806 // Random buggy state that doesn't decode?? 1807 len = jio_snprintf(buf, buflen, "#%d", trap_state); 1808 } else { 1809 len = jio_snprintf(buf, buflen, "%s%s", 1810 trap_reason_name(reason), 1811 recomp_flag ? " recompiled" : ""); 1812 } 1813 if (len >= buflen) 1814 buf[buflen-1] = '\0'; 1815 return buf; 1816 } 1817 1818 1819 //--------------------------------statics-------------------------------------- 1820 Deoptimization::DeoptAction Deoptimization::_unloaded_action 1821 = Deoptimization::Action_reinterpret; 1822 const char* Deoptimization::_trap_reason_name[Reason_LIMIT] = { 1823 // Note: Keep this in sync. with enum DeoptReason. 1824 "none", 1825 "null_check", 1826 "null_assert", 1827 "range_check", 1828 "class_check", 1829 "array_check", 1830 "intrinsic", 1831 "bimorphic", 1832 "unloaded", 1833 "uninitialized", 1834 "unreached", 1835 "unhandled", 1836 "constraint", 1837 "div0_check", 1838 "age", 1839 "predicate", 1840 "loop_limit_check", 1841 "speculate_class_check", 1842 "speculate_null_check", 1843 "rtm_state_change" 1844 }; 1845 const char* Deoptimization::_trap_action_name[Action_LIMIT] = { 1846 // Note: Keep this in sync. with enum DeoptAction. 1847 "none", 1848 "maybe_recompile", 1849 "reinterpret", 1850 "make_not_entrant", 1851 "make_not_compilable" 1852 }; 1853 1854 const char* Deoptimization::trap_reason_name(int reason) { 1855 if (reason == Reason_many) return "many"; 1856 if ((uint)reason < Reason_LIMIT) 1857 return _trap_reason_name[reason]; 1858 static char buf[20]; 1859 sprintf(buf, "reason%d", reason); 1860 return buf; 1861 } 1862 const char* Deoptimization::trap_action_name(int action) { 1863 if ((uint)action < Action_LIMIT) 1864 return _trap_action_name[action]; 1865 static char buf[20]; 1866 sprintf(buf, "action%d", action); 1867 return buf; 1868 } 1869 1870 // This is used for debugging and diagnostics, including LogFile output. 1871 const char* Deoptimization::format_trap_request(char* buf, size_t buflen, 1872 int trap_request) { 1873 jint unloaded_class_index = trap_request_index(trap_request); 1874 const char* reason = trap_reason_name(trap_request_reason(trap_request)); 1875 const char* action = trap_action_name(trap_request_action(trap_request)); 1876 size_t len; 1877 if (unloaded_class_index < 0) { 1878 len = jio_snprintf(buf, buflen, "reason='%s' action='%s'", 1879 reason, action); 1880 } else { 1881 len = jio_snprintf(buf, buflen, "reason='%s' action='%s' index='%d'", 1882 reason, action, unloaded_class_index); 1883 } 1884 if (len >= buflen) 1885 buf[buflen-1] = '\0'; 1886 return buf; 1887 } 1888 1889 juint Deoptimization::_deoptimization_hist 1890 [Deoptimization::Reason_LIMIT] 1891 [1 + Deoptimization::Action_LIMIT] 1892 [Deoptimization::BC_CASE_LIMIT] 1893 = {0}; 1894 1895 enum { 1896 LSB_BITS = 8, 1897 LSB_MASK = right_n_bits(LSB_BITS) 1898 }; 1899 1900 void Deoptimization::gather_statistics(DeoptReason reason, DeoptAction action, 1901 Bytecodes::Code bc) { 1902 assert(reason >= 0 && reason < Reason_LIMIT, "oob"); 1903 assert(action >= 0 && action < Action_LIMIT, "oob"); 1904 _deoptimization_hist[Reason_none][0][0] += 1; // total 1905 _deoptimization_hist[reason][0][0] += 1; // per-reason total 1906 juint* cases = _deoptimization_hist[reason][1+action]; 1907 juint* bc_counter_addr = NULL; 1908 juint bc_counter = 0; 1909 // Look for an unused counter, or an exact match to this BC. 1910 if (bc != Bytecodes::_illegal) { 1911 for (int bc_case = 0; bc_case < BC_CASE_LIMIT; bc_case++) { 1912 juint* counter_addr = &cases[bc_case]; 1913 juint counter = *counter_addr; 1914 if ((counter == 0 && bc_counter_addr == NULL) 1915 || (Bytecodes::Code)(counter & LSB_MASK) == bc) { 1916 // this counter is either free or is already devoted to this BC 1917 bc_counter_addr = counter_addr; 1918 bc_counter = counter | bc; 1919 } 1920 } 1921 } 1922 if (bc_counter_addr == NULL) { 1923 // Overflow, or no given bytecode. 1924 bc_counter_addr = &cases[BC_CASE_LIMIT-1]; 1925 bc_counter = (*bc_counter_addr & ~LSB_MASK); // clear LSB 1926 } 1927 *bc_counter_addr = bc_counter + (1 << LSB_BITS); 1928 } 1929 1930 jint Deoptimization::total_deoptimization_count() { 1931 return _deoptimization_hist[Reason_none][0][0]; 1932 } 1933 1934 jint Deoptimization::deoptimization_count(DeoptReason reason) { 1935 assert(reason >= 0 && reason < Reason_LIMIT, "oob"); 1936 return _deoptimization_hist[reason][0][0]; 1937 } 1938 1939 void Deoptimization::print_statistics() { 1940 juint total = total_deoptimization_count(); 1941 juint account = total; 1942 if (total != 0) { 1943 ttyLocker ttyl; 1944 if (xtty != NULL) xtty->head("statistics type='deoptimization'"); 1945 tty->print_cr("Deoptimization traps recorded:"); 1946 #define PRINT_STAT_LINE(name, r) \ 1947 tty->print_cr(" %4d (%4.1f%%) %s", (int)(r), ((r) * 100.0) / total, name); 1948 PRINT_STAT_LINE("total", total); 1949 // For each non-zero entry in the histogram, print the reason, 1950 // the action, and (if specifically known) the type of bytecode. 1951 for (int reason = 0; reason < Reason_LIMIT; reason++) { 1952 for (int action = 0; action < Action_LIMIT; action++) { 1953 juint* cases = _deoptimization_hist[reason][1+action]; 1954 for (int bc_case = 0; bc_case < BC_CASE_LIMIT; bc_case++) { 1955 juint counter = cases[bc_case]; 1956 if (counter != 0) { 1957 char name[1*K]; 1958 Bytecodes::Code bc = (Bytecodes::Code)(counter & LSB_MASK); 1959 if (bc_case == BC_CASE_LIMIT && (int)bc == 0) 1960 bc = Bytecodes::_illegal; 1961 sprintf(name, "%s/%s/%s", 1962 trap_reason_name(reason), 1963 trap_action_name(action), 1964 Bytecodes::is_defined(bc)? Bytecodes::name(bc): "other"); 1965 juint r = counter >> LSB_BITS; 1966 tty->print_cr(" %40s: " UINT32_FORMAT " (%.1f%%)", name, r, (r * 100.0) / total); 1967 account -= r; 1968 } 1969 } 1970 } 1971 } 1972 if (account != 0) { 1973 PRINT_STAT_LINE("unaccounted", account); 1974 } 1975 #undef PRINT_STAT_LINE 1976 if (xtty != NULL) xtty->tail("statistics"); 1977 } 1978 } 1979 #else // COMPILER2 || SHARK 1980 1981 1982 // Stubs for C1 only system. 1983 bool Deoptimization::trap_state_is_recompiled(int trap_state) { 1984 return false; 1985 } 1986 1987 const char* Deoptimization::trap_reason_name(int reason) { 1988 return "unknown"; 1989 } 1990 1991 void Deoptimization::print_statistics() { 1992 // no output 1993 } 1994 1995 void 1996 Deoptimization::update_method_data_from_interpreter(MethodData* trap_mdo, int trap_bci, int reason) { 1997 // no udpate 1998 } 1999 2000 int Deoptimization::trap_state_has_reason(int trap_state, int reason) { 2001 return 0; 2002 } 2003 2004 void Deoptimization::gather_statistics(DeoptReason reason, DeoptAction action, 2005 Bytecodes::Code bc) { 2006 // no update 2007 } 2008 2009 const char* Deoptimization::format_trap_state(char* buf, size_t buflen, 2010 int trap_state) { 2011 jio_snprintf(buf, buflen, "#%d", trap_state); 2012 return buf; 2013 } 2014 2015 #endif // COMPILER2 || SHARK