1 /*
2 * Copyright (c) 1997, 2024, 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/javaClasses.inline.hpp"
27 #include "classfile/symbolTable.hpp"
28 #include "classfile/systemDictionary.hpp"
29 #include "classfile/vmClasses.hpp"
30 #include "code/codeCache.hpp"
31 #include "code/debugInfoRec.hpp"
32 #include "code/nmethod.hpp"
33 #include "code/pcDesc.hpp"
34 #include "code/scopeDesc.hpp"
35 #include "compiler/compilationPolicy.hpp"
36 #include "compiler/compilerDefinitions.inline.hpp"
37 #include "gc/shared/collectedHeap.hpp"
38 #include "gc/shared/memAllocator.hpp"
39 #include "interpreter/bytecode.hpp"
40 #include "interpreter/bytecodeStream.hpp"
41 #include "interpreter/interpreter.hpp"
42 #include "interpreter/oopMapCache.hpp"
43 #include "jvm.h"
44 #include "logging/log.hpp"
45 #include "logging/logLevel.hpp"
46 #include "logging/logMessage.hpp"
47 #include "logging/logStream.hpp"
48 #include "memory/allocation.inline.hpp"
49 #include "memory/oopFactory.hpp"
50 #include "memory/resourceArea.hpp"
51 #include "memory/universe.hpp"
52 #include "oops/constantPool.hpp"
53 #include "oops/fieldStreams.inline.hpp"
54 #include "oops/method.hpp"
55 #include "oops/objArrayKlass.hpp"
56 #include "oops/objArrayOop.inline.hpp"
57 #include "oops/oop.inline.hpp"
58 #include "oops/typeArrayOop.inline.hpp"
59 #include "oops/verifyOopClosure.hpp"
60 #include "prims/jvmtiDeferredUpdates.hpp"
61 #include "prims/jvmtiExport.hpp"
62 #include "prims/jvmtiThreadState.hpp"
63 #include "prims/methodHandles.hpp"
64 #include "prims/vectorSupport.hpp"
65 #include "runtime/atomic.hpp"
66 #include "runtime/basicLock.inline.hpp"
67 #include "runtime/continuation.hpp"
68 #include "runtime/continuationEntry.inline.hpp"
69 #include "runtime/deoptimization.hpp"
70 #include "runtime/escapeBarrier.hpp"
71 #include "runtime/fieldDescriptor.hpp"
72 #include "runtime/fieldDescriptor.inline.hpp"
73 #include "runtime/frame.inline.hpp"
74 #include "runtime/handles.inline.hpp"
75 #include "runtime/interfaceSupport.inline.hpp"
76 #include "runtime/javaThread.hpp"
77 #include "runtime/jniHandles.inline.hpp"
78 #include "runtime/keepStackGCProcessed.hpp"
79 #include "runtime/lightweightSynchronizer.hpp"
80 #include "runtime/lockStack.inline.hpp"
81 #include "runtime/objectMonitor.inline.hpp"
82 #include "runtime/osThread.hpp"
83 #include "runtime/perfData.inline.hpp"
84 #include "runtime/safepointVerifiers.hpp"
85 #include "runtime/sharedRuntime.hpp"
86 #include "runtime/signature.hpp"
87 #include "runtime/stackFrameStream.inline.hpp"
88 #include "runtime/stackValue.hpp"
89 #include "runtime/stackWatermarkSet.hpp"
90 #include "runtime/stubRoutines.hpp"
91 #include "runtime/synchronizer.inline.hpp"
92 #include "runtime/threadSMR.hpp"
93 #include "runtime/threadWXSetters.inline.hpp"
94 #include "runtime/vframe.hpp"
95 #include "runtime/vframeArray.hpp"
96 #include "runtime/vframe_hp.hpp"
97 #include "runtime/vmOperations.hpp"
98 #include "services/management.hpp"
99 #include "utilities/checkedCast.hpp"
100 #include "utilities/events.hpp"
101 #include "utilities/growableArray.hpp"
102 #include "utilities/macros.hpp"
103 #include "utilities/preserveException.hpp"
104 #include "utilities/xmlstream.hpp"
105 #if INCLUDE_JFR
106 #include "jfr/jfrEvents.hpp"
107 #include "jfr/metadata/jfrSerializer.hpp"
108 #endif
109
110 uint64_t DeoptimizationScope::_committed_deopt_gen = 0;
111 uint64_t DeoptimizationScope::_active_deopt_gen = 1;
112 bool DeoptimizationScope::_committing_in_progress = false;
113
114 DeoptimizationScope::DeoptimizationScope() : _required_gen(0) {
115 DEBUG_ONLY(_deopted = false;)
116
117 MutexLocker ml(NMethodState_lock, Mutex::_no_safepoint_check_flag);
118 // If there is nothing to deopt _required_gen is the same as comitted.
119 _required_gen = DeoptimizationScope::_committed_deopt_gen;
120 }
121
122 DeoptimizationScope::~DeoptimizationScope() {
123 assert(_deopted, "Deopt not executed");
124 }
125
126 void DeoptimizationScope::mark(nmethod* nm, bool inc_recompile_counts) {
127 if (!nm->can_be_deoptimized()) {
128 return;
129 }
130
131 ConditionalMutexLocker ml(NMethodState_lock, !NMethodState_lock->owned_by_self(), Mutex::_no_safepoint_check_flag);
132
133 // If it's already marked but we still need it to be deopted.
134 if (nm->is_marked_for_deoptimization()) {
135 dependent(nm);
136 return;
137 }
138
139 nmethod::DeoptimizationStatus status =
140 inc_recompile_counts ? nmethod::deoptimize : nmethod::deoptimize_noupdate;
141 Atomic::store(&nm->_deoptimization_status, status);
142
143 // Make sure active is not committed
144 assert(DeoptimizationScope::_committed_deopt_gen < DeoptimizationScope::_active_deopt_gen, "Must be");
145 assert(nm->_deoptimization_generation == 0, "Is already marked");
146
147 nm->_deoptimization_generation = DeoptimizationScope::_active_deopt_gen;
148 _required_gen = DeoptimizationScope::_active_deopt_gen;
149 }
150
151 void DeoptimizationScope::dependent(nmethod* nm) {
152 ConditionalMutexLocker ml(NMethodState_lock, !NMethodState_lock->owned_by_self(), Mutex::_no_safepoint_check_flag);
153
154 // A method marked by someone else may have a _required_gen lower than what we marked with.
155 // Therefore only store it if it's higher than _required_gen.
156 if (_required_gen < nm->_deoptimization_generation) {
157 _required_gen = nm->_deoptimization_generation;
158 }
159 }
160
161 void DeoptimizationScope::deoptimize_marked() {
162 assert(!_deopted, "Already deopted");
163
164 // We are not alive yet.
165 if (!Universe::is_fully_initialized()) {
166 DEBUG_ONLY(_deopted = true;)
167 return;
168 }
169
170 // Safepoints are a special case, handled here.
171 if (SafepointSynchronize::is_at_safepoint()) {
172 DeoptimizationScope::_committed_deopt_gen = DeoptimizationScope::_active_deopt_gen;
173 DeoptimizationScope::_active_deopt_gen++;
174 Deoptimization::deoptimize_all_marked();
175 DEBUG_ONLY(_deopted = true;)
176 return;
177 }
178
179 uint64_t comitting = 0;
180 bool wait = false;
181 while (true) {
182 {
183 ConditionalMutexLocker ml(NMethodState_lock, !NMethodState_lock->owned_by_self(), Mutex::_no_safepoint_check_flag);
184
185 // First we check if we or someone else already deopted the gen we want.
186 if (DeoptimizationScope::_committed_deopt_gen >= _required_gen) {
187 DEBUG_ONLY(_deopted = true;)
188 return;
189 }
190 if (!_committing_in_progress) {
191 // The version we are about to commit.
192 comitting = DeoptimizationScope::_active_deopt_gen;
193 // Make sure new marks use a higher gen.
194 DeoptimizationScope::_active_deopt_gen++;
195 _committing_in_progress = true;
196 wait = false;
197 } else {
198 // Another thread is handshaking and committing a gen.
199 wait = true;
200 }
201 }
202 if (wait) {
203 // Wait and let the concurrent handshake be performed.
204 ThreadBlockInVM tbivm(JavaThread::current());
205 os::naked_yield();
206 } else {
207 // Performs the handshake.
208 Deoptimization::deoptimize_all_marked(); // May safepoint and an additional deopt may have occurred.
209 DEBUG_ONLY(_deopted = true;)
210 {
211 ConditionalMutexLocker ml(NMethodState_lock, !NMethodState_lock->owned_by_self(), Mutex::_no_safepoint_check_flag);
212
213 // Make sure that committed doesn't go backwards.
214 // Should only happen if we did a deopt during a safepoint above.
215 if (DeoptimizationScope::_committed_deopt_gen < comitting) {
216 DeoptimizationScope::_committed_deopt_gen = comitting;
217 }
218 _committing_in_progress = false;
219
220 assert(DeoptimizationScope::_committed_deopt_gen >= _required_gen, "Must be");
221
222 return;
223 }
224 }
225 }
226 }
227
228 Deoptimization::UnrollBlock::UnrollBlock(int size_of_deoptimized_frame,
229 int caller_adjustment,
230 int caller_actual_parameters,
231 int number_of_frames,
232 intptr_t* frame_sizes,
233 address* frame_pcs,
234 BasicType return_type,
235 int exec_mode) {
236 _size_of_deoptimized_frame = size_of_deoptimized_frame;
237 _caller_adjustment = caller_adjustment;
238 _caller_actual_parameters = caller_actual_parameters;
239 _number_of_frames = number_of_frames;
240 _frame_sizes = frame_sizes;
241 _frame_pcs = frame_pcs;
242 _register_block = NEW_C_HEAP_ARRAY(intptr_t, RegisterMap::reg_count * 2, mtCompiler);
243 _return_type = return_type;
244 _initial_info = 0;
245 // PD (x86 only)
246 _counter_temp = 0;
247 _unpack_kind = exec_mode;
248 _sender_sp_temp = 0;
249
250 _total_frame_sizes = size_of_frames();
251 assert(exec_mode >= 0 && exec_mode < Unpack_LIMIT, "Unexpected exec_mode");
252 }
253
254 Deoptimization::UnrollBlock::~UnrollBlock() {
255 FREE_C_HEAP_ARRAY(intptr_t, _frame_sizes);
256 FREE_C_HEAP_ARRAY(intptr_t, _frame_pcs);
257 FREE_C_HEAP_ARRAY(intptr_t, _register_block);
258 }
259
260 int Deoptimization::UnrollBlock::size_of_frames() const {
261 // Account first for the adjustment of the initial frame
262 intptr_t result = _caller_adjustment;
263 for (int index = 0; index < number_of_frames(); index++) {
264 result += frame_sizes()[index];
265 }
266 return checked_cast<int>(result);
267 }
268
269 void Deoptimization::UnrollBlock::print() {
270 ResourceMark rm;
271 stringStream st;
272 st.print_cr("UnrollBlock");
273 st.print_cr(" size_of_deoptimized_frame = %d", _size_of_deoptimized_frame);
274 st.print( " frame_sizes: ");
275 for (int index = 0; index < number_of_frames(); index++) {
276 st.print(INTX_FORMAT " ", frame_sizes()[index]);
277 }
278 st.cr();
279 tty->print_raw(st.freeze());
280 }
281
282 // In order to make fetch_unroll_info work properly with escape
283 // analysis, the method was changed from JRT_LEAF to JRT_BLOCK_ENTRY.
284 // The actual reallocation of previously eliminated objects occurs in realloc_objects,
285 // which is called from the method fetch_unroll_info_helper below.
286 JRT_BLOCK_ENTRY_PROF(Deoptimization::UnrollBlock*, Deoptimization, fetch_unroll_info, Deoptimization::fetch_unroll_info(JavaThread* current, int exec_mode))
287 // fetch_unroll_info() is called at the beginning of the deoptimization
288 // handler. Note this fact before we start generating temporary frames
289 // that can confuse an asynchronous stack walker. This counter is
290 // decremented at the end of unpack_frames().
291 current->inc_in_deopt_handler();
292
293 if (exec_mode == Unpack_exception) {
294 // When we get here, a callee has thrown an exception into a deoptimized
295 // frame. That throw might have deferred stack watermark checking until
296 // after unwinding. So we deal with such deferred requests here.
297 StackWatermarkSet::after_unwind(current);
298 }
299
300 return fetch_unroll_info_helper(current, exec_mode);
301 JRT_END
302
303 #if COMPILER2_OR_JVMCI
304 // print information about reallocated objects
305 static void print_objects(JavaThread* deoptee_thread,
306 GrowableArray<ScopeValue*>* objects, bool realloc_failures) {
307 ResourceMark rm;
308 stringStream st; // change to logStream with logging
309 st.print_cr("REALLOC OBJECTS in thread " INTPTR_FORMAT, p2i(deoptee_thread));
310 fieldDescriptor fd;
311
312 for (int i = 0; i < objects->length(); i++) {
313 ObjectValue* sv = (ObjectValue*) objects->at(i);
314 Handle obj = sv->value();
315
316 if (obj.is_null()) {
317 st.print_cr(" nullptr");
318 continue;
319 }
320
321 Klass* k = java_lang_Class::as_Klass(sv->klass()->as_ConstantOopReadValue()->value()());
322
323 st.print(" object <" INTPTR_FORMAT "> of type ", p2i(sv->value()()));
324 k->print_value_on(&st);
325 st.print_cr(" allocated (" SIZE_FORMAT " bytes)", obj->size() * HeapWordSize);
326
327 if (Verbose && k != nullptr) {
328 k->oop_print_on(obj(), &st);
329 }
330 }
331 tty->print_raw(st.freeze());
332 }
333
334 static bool rematerialize_objects(JavaThread* thread, int exec_mode, nmethod* compiled_method,
335 frame& deoptee, RegisterMap& map, GrowableArray<compiledVFrame*>* chunk,
336 bool& deoptimized_objects) {
337 bool realloc_failures = false;
338 assert (chunk->at(0)->scope() != nullptr,"expect only compiled java frames");
339
340 JavaThread* deoptee_thread = chunk->at(0)->thread();
341 assert(exec_mode == Deoptimization::Unpack_none || (deoptee_thread == thread),
342 "a frame can only be deoptimized by the owner thread");
343
344 GrowableArray<ScopeValue*>* objects = chunk->at(0)->scope()->objects_to_rematerialize(deoptee, map);
345
346 // The flag return_oop() indicates call sites which return oop
347 // in compiled code. Such sites include java method calls,
348 // runtime calls (for example, used to allocate new objects/arrays
349 // on slow code path) and any other calls generated in compiled code.
350 // It is not guaranteed that we can get such information here only
351 // by analyzing bytecode in deoptimized frames. This is why this flag
352 // is set during method compilation (see Compile::Process_OopMap_Node()).
353 // If the previous frame was popped or if we are dispatching an exception,
354 // we don't have an oop result.
355 bool save_oop_result = chunk->at(0)->scope()->return_oop() && !thread->popframe_forcing_deopt_reexecution() && (exec_mode == Deoptimization::Unpack_deopt);
356 Handle return_value;
357 if (save_oop_result) {
358 // Reallocation may trigger GC. If deoptimization happened on return from
359 // call which returns oop we need to save it since it is not in oopmap.
360 oop result = deoptee.saved_oop_result(&map);
361 assert(oopDesc::is_oop_or_null(result), "must be oop");
362 return_value = Handle(thread, result);
363 assert(Universe::heap()->is_in_or_null(result), "must be heap pointer");
364 if (TraceDeoptimization) {
365 tty->print_cr("SAVED OOP RESULT " INTPTR_FORMAT " in thread " INTPTR_FORMAT, p2i(result), p2i(thread));
366 tty->cr();
367 }
368 }
369 if (objects != nullptr) {
370 if (exec_mode == Deoptimization::Unpack_none) {
371 assert(thread->thread_state() == _thread_in_vm, "assumption");
372 JavaThread* THREAD = thread; // For exception macros.
373 // Clear pending OOM if reallocation fails and return true indicating allocation failure
374 realloc_failures = Deoptimization::realloc_objects(thread, &deoptee, &map, objects, CHECK_AND_CLEAR_(true));
375 deoptimized_objects = true;
376 } else {
377 JavaThread* current = thread; // For JRT_BLOCK
378 JRT_BLOCK
379 realloc_failures = Deoptimization::realloc_objects(thread, &deoptee, &map, objects, THREAD);
380 JRT_END
381 }
382 bool skip_internal = (compiled_method != nullptr) && !compiled_method->is_compiled_by_jvmci();
383 Deoptimization::reassign_fields(&deoptee, &map, objects, realloc_failures, skip_internal);
384 if (TraceDeoptimization) {
385 print_objects(deoptee_thread, objects, realloc_failures);
386 }
387 }
388 if (save_oop_result) {
389 // Restore result.
390 deoptee.set_saved_oop_result(&map, return_value());
391 }
392 return realloc_failures;
393 }
394
395 static void restore_eliminated_locks(JavaThread* thread, GrowableArray<compiledVFrame*>* chunk, bool realloc_failures,
396 frame& deoptee, int exec_mode, bool& deoptimized_objects) {
397 JavaThread* deoptee_thread = chunk->at(0)->thread();
398 assert(!EscapeBarrier::objs_are_deoptimized(deoptee_thread, deoptee.id()), "must relock just once");
399 assert(thread == Thread::current(), "should be");
400 HandleMark hm(thread);
401 #ifndef PRODUCT
402 bool first = true;
403 #endif // !PRODUCT
404 // Start locking from outermost/oldest frame
405 for (int i = (chunk->length() - 1); i >= 0; i--) {
406 compiledVFrame* cvf = chunk->at(i);
407 assert (cvf->scope() != nullptr,"expect only compiled java frames");
408 GrowableArray<MonitorInfo*>* monitors = cvf->monitors();
409 if (monitors->is_nonempty()) {
410 bool relocked = Deoptimization::relock_objects(thread, monitors, deoptee_thread, deoptee,
411 exec_mode, realloc_failures);
412 deoptimized_objects = deoptimized_objects || relocked;
413 #ifndef PRODUCT
414 if (PrintDeoptimizationDetails) {
415 ResourceMark rm;
416 stringStream st;
417 for (int j = 0; j < monitors->length(); j++) {
418 MonitorInfo* mi = monitors->at(j);
419 if (mi->eliminated()) {
420 if (first) {
421 first = false;
422 st.print_cr("RELOCK OBJECTS in thread " INTPTR_FORMAT, p2i(thread));
423 }
424 if (exec_mode == Deoptimization::Unpack_none) {
425 ObjectMonitor* monitor = deoptee_thread->current_waiting_monitor();
426 if (monitor != nullptr && monitor->object() == mi->owner()) {
427 st.print_cr(" object <" INTPTR_FORMAT "> DEFERRED relocking after wait", p2i(mi->owner()));
428 continue;
429 }
430 }
431 if (mi->owner_is_scalar_replaced()) {
432 Klass* k = java_lang_Class::as_Klass(mi->owner_klass());
433 st.print_cr(" failed reallocation for klass %s", k->external_name());
434 } else {
435 st.print_cr(" object <" INTPTR_FORMAT "> locked", p2i(mi->owner()));
436 }
437 }
438 }
439 tty->print_raw(st.freeze());
440 }
441 #endif // !PRODUCT
442 }
443 }
444 }
445
446 // Deoptimize objects, that is reallocate and relock them, just before they escape through JVMTI.
447 // The given vframes cover one physical frame.
448 bool Deoptimization::deoptimize_objects_internal(JavaThread* thread, GrowableArray<compiledVFrame*>* chunk,
449 bool& realloc_failures) {
450 frame deoptee = chunk->at(0)->fr();
451 JavaThread* deoptee_thread = chunk->at(0)->thread();
452 nmethod* nm = deoptee.cb()->as_nmethod_or_null();
453 RegisterMap map(chunk->at(0)->register_map());
454 bool deoptimized_objects = false;
455
456 bool const jvmci_enabled = JVMCI_ONLY(EnableJVMCI) NOT_JVMCI(false);
457
458 // Reallocate the non-escaping objects and restore their fields.
459 if (jvmci_enabled COMPILER2_PRESENT(|| (DoEscapeAnalysis && EliminateAllocations)
460 || EliminateAutoBox || EnableVectorAggressiveReboxing)) {
461 realloc_failures = rematerialize_objects(thread, Unpack_none, nm, deoptee, map, chunk, deoptimized_objects);
462 }
463
464 // MonitorInfo structures used in eliminate_locks are not GC safe.
465 NoSafepointVerifier no_safepoint;
466
467 // Now relock objects if synchronization on them was eliminated.
468 if (jvmci_enabled COMPILER2_PRESENT(|| ((DoEscapeAnalysis || EliminateNestedLocks) && EliminateLocks))) {
469 restore_eliminated_locks(thread, chunk, realloc_failures, deoptee, Unpack_none, deoptimized_objects);
470 }
471 return deoptimized_objects;
472 }
473 #endif // COMPILER2_OR_JVMCI
474
475 // This is factored, since it is both called from a JRT_LEAF (deoptimization) and a JRT_ENTRY (uncommon_trap)
476 Deoptimization::UnrollBlock* Deoptimization::fetch_unroll_info_helper(JavaThread* current, int exec_mode) {
477 // When we get here we are about to unwind the deoptee frame. In order to
478 // catch not yet safe to use frames, the following stack watermark barrier
479 // poll will make such frames safe to use.
480 StackWatermarkSet::before_unwind(current);
481
482 // Note: there is a safepoint safety issue here. No matter whether we enter
483 // via vanilla deopt or uncommon trap we MUST NOT stop at a safepoint once
484 // the vframeArray is created.
485 //
486
487 // Allocate our special deoptimization ResourceMark
488 DeoptResourceMark* dmark = new DeoptResourceMark(current);
489 assert(current->deopt_mark() == nullptr, "Pending deopt!");
490 current->set_deopt_mark(dmark);
491
492 frame stub_frame = current->last_frame(); // Makes stack walkable as side effect
493 RegisterMap map(current,
494 RegisterMap::UpdateMap::include,
495 RegisterMap::ProcessFrames::include,
496 RegisterMap::WalkContinuation::skip);
497 RegisterMap dummy_map(current,
498 RegisterMap::UpdateMap::skip,
499 RegisterMap::ProcessFrames::include,
500 RegisterMap::WalkContinuation::skip);
501 // Now get the deoptee with a valid map
502 frame deoptee = stub_frame.sender(&map);
503 // Set the deoptee nmethod
504 assert(current->deopt_compiled_method() == nullptr, "Pending deopt!");
505 nmethod* nm = deoptee.cb()->as_nmethod_or_null();
506 current->set_deopt_compiled_method(nm);
507
508 if (VerifyStack) {
509 current->validate_frame_layout();
510 }
511
512 // Create a growable array of VFrames where each VFrame represents an inlined
513 // Java frame. This storage is allocated with the usual system arena.
514 assert(deoptee.is_compiled_frame(), "Wrong frame type");
515 GrowableArray<compiledVFrame*>* chunk = new GrowableArray<compiledVFrame*>(10);
516 vframe* vf = vframe::new_vframe(&deoptee, &map, current);
517 while (!vf->is_top()) {
518 assert(vf->is_compiled_frame(), "Wrong frame type");
519 chunk->push(compiledVFrame::cast(vf));
520 vf = vf->sender();
521 }
522 assert(vf->is_compiled_frame(), "Wrong frame type");
523 chunk->push(compiledVFrame::cast(vf));
524
525 bool realloc_failures = false;
526
527 #if COMPILER2_OR_JVMCI
528 bool const jvmci_enabled = JVMCI_ONLY(EnableJVMCI) NOT_JVMCI(false);
529
530 // Reallocate the non-escaping objects and restore their fields. Then
531 // relock objects if synchronization on them was eliminated.
532 if (jvmci_enabled COMPILER2_PRESENT( || (DoEscapeAnalysis && EliminateAllocations)
533 || EliminateAutoBox || EnableVectorAggressiveReboxing )) {
534 bool unused;
535 realloc_failures = rematerialize_objects(current, exec_mode, nm, deoptee, map, chunk, unused);
536 }
537 #endif // COMPILER2_OR_JVMCI
538
539 // Ensure that no safepoint is taken after pointers have been stored
540 // in fields of rematerialized objects. If a safepoint occurs from here on
541 // out the java state residing in the vframeArray will be missed.
542 // Locks may be rebaised in a safepoint.
543 NoSafepointVerifier no_safepoint;
544
545 #if COMPILER2_OR_JVMCI
546 if ((jvmci_enabled COMPILER2_PRESENT( || ((DoEscapeAnalysis || EliminateNestedLocks) && EliminateLocks) ))
547 && !EscapeBarrier::objs_are_deoptimized(current, deoptee.id())) {
548 bool unused = false;
549 restore_eliminated_locks(current, chunk, realloc_failures, deoptee, exec_mode, unused);
550 }
551 #endif // COMPILER2_OR_JVMCI
552
553 ScopeDesc* trap_scope = chunk->at(0)->scope();
554 Handle exceptionObject;
555 if (trap_scope->rethrow_exception()) {
556 #ifndef PRODUCT
557 if (PrintDeoptimizationDetails) {
558 tty->print_cr("Exception to be rethrown in the interpreter for method %s::%s at bci %d", trap_scope->method()->method_holder()->name()->as_C_string(), trap_scope->method()->name()->as_C_string(), trap_scope->bci());
559 }
560 #endif // !PRODUCT
561
562 GrowableArray<ScopeValue*>* expressions = trap_scope->expressions();
563 guarantee(expressions != nullptr && expressions->length() > 0, "must have exception to throw");
564 ScopeValue* topOfStack = expressions->top();
565 exceptionObject = StackValue::create_stack_value(&deoptee, &map, topOfStack)->get_obj();
566 guarantee(exceptionObject() != nullptr, "exception oop can not be null");
567 }
568
569 vframeArray* array = create_vframeArray(current, deoptee, &map, chunk, realloc_failures);
570 #if COMPILER2_OR_JVMCI
571 if (realloc_failures) {
572 // This destroys all ScopedValue bindings.
573 current->clear_scopedValueBindings();
574 pop_frames_failed_reallocs(current, array);
575 }
576 #endif
577
578 assert(current->vframe_array_head() == nullptr, "Pending deopt!");
579 current->set_vframe_array_head(array);
580
581 // Now that the vframeArray has been created if we have any deferred local writes
582 // added by jvmti then we can free up that structure as the data is now in the
583 // vframeArray
584
585 JvmtiDeferredUpdates::delete_updates_for_frame(current, array->original().id());
586
587 // Compute the caller frame based on the sender sp of stub_frame and stored frame sizes info.
588 CodeBlob* cb = stub_frame.cb();
589 // Verify we have the right vframeArray
590 assert(cb->frame_size() >= 0, "Unexpected frame size");
591 intptr_t* unpack_sp = stub_frame.sp() + cb->frame_size();
592
593 // If the deopt call site is a MethodHandle invoke call site we have
594 // to adjust the unpack_sp.
595 nmethod* deoptee_nm = deoptee.cb()->as_nmethod_or_null();
596 if (deoptee_nm != nullptr && deoptee_nm->is_method_handle_return(deoptee.pc()))
597 unpack_sp = deoptee.unextended_sp();
598
599 #ifdef ASSERT
600 assert(cb->is_deoptimization_stub() ||
601 cb->is_uncommon_trap_stub() ||
602 strcmp("Stub<DeoptimizationStub.deoptimizationHandler>", cb->name()) == 0 ||
603 strcmp("Stub<UncommonTrapStub.uncommonTrapHandler>", cb->name()) == 0,
604 "unexpected code blob: %s", cb->name());
605 #endif
606
607 // This is a guarantee instead of an assert because if vframe doesn't match
608 // we will unpack the wrong deoptimized frame and wind up in strange places
609 // where it will be very difficult to figure out what went wrong. Better
610 // to die an early death here than some very obscure death later when the
611 // trail is cold.
612 // Note: on ia64 this guarantee can be fooled by frames with no memory stack
613 // in that it will fail to detect a problem when there is one. This needs
614 // more work in tiger timeframe.
615 guarantee(array->unextended_sp() == unpack_sp, "vframe_array_head must contain the vframeArray to unpack");
616
617 int number_of_frames = array->frames();
618
619 // Compute the vframes' sizes. Note that frame_sizes[] entries are ordered from outermost to innermost
620 // virtual activation, which is the reverse of the elements in the vframes array.
621 intptr_t* frame_sizes = NEW_C_HEAP_ARRAY(intptr_t, number_of_frames, mtCompiler);
622 // +1 because we always have an interpreter return address for the final slot.
623 address* frame_pcs = NEW_C_HEAP_ARRAY(address, number_of_frames + 1, mtCompiler);
624 int popframe_extra_args = 0;
625 // Create an interpreter return address for the stub to use as its return
626 // address so the skeletal frames are perfectly walkable
627 frame_pcs[number_of_frames] = Interpreter::deopt_entry(vtos, 0);
628
629 // PopFrame requires that the preserved incoming arguments from the recently-popped topmost
630 // activation be put back on the expression stack of the caller for reexecution
631 if (JvmtiExport::can_pop_frame() && current->popframe_forcing_deopt_reexecution()) {
632 popframe_extra_args = in_words(current->popframe_preserved_args_size_in_words());
633 }
634
635 // Find the current pc for sender of the deoptee. Since the sender may have been deoptimized
636 // itself since the deoptee vframeArray was created we must get a fresh value of the pc rather
637 // than simply use array->sender.pc(). This requires us to walk the current set of frames
638 //
639 frame deopt_sender = stub_frame.sender(&dummy_map); // First is the deoptee frame
640 deopt_sender = deopt_sender.sender(&dummy_map); // Now deoptee caller
641
642 // It's possible that the number of parameters at the call site is
643 // different than number of arguments in the callee when method
644 // handles are used. If the caller is interpreted get the real
645 // value so that the proper amount of space can be added to it's
646 // frame.
647 bool caller_was_method_handle = false;
648 if (deopt_sender.is_interpreted_frame()) {
649 methodHandle method(current, deopt_sender.interpreter_frame_method());
650 Bytecode_invoke cur = Bytecode_invoke_check(method, deopt_sender.interpreter_frame_bci());
651 if (cur.is_invokedynamic() || cur.is_invokehandle()) {
652 // Method handle invokes may involve fairly arbitrary chains of
653 // calls so it's impossible to know how much actual space the
654 // caller has for locals.
655 caller_was_method_handle = true;
656 }
657 }
658
659 //
660 // frame_sizes/frame_pcs[0] oldest frame (int or c2i)
661 // frame_sizes/frame_pcs[1] next oldest frame (int)
662 // frame_sizes/frame_pcs[n] youngest frame (int)
663 //
664 // Now a pc in frame_pcs is actually the return address to the frame's caller (a frame
665 // owns the space for the return address to it's caller). Confusing ain't it.
666 //
667 // The vframe array can address vframes with indices running from
668 // 0.._frames-1. Index 0 is the youngest frame and _frame - 1 is the oldest (root) frame.
669 // When we create the skeletal frames we need the oldest frame to be in the zero slot
670 // in the frame_sizes/frame_pcs so the assembly code can do a trivial walk.
671 // so things look a little strange in this loop.
672 //
673 int callee_parameters = 0;
674 int callee_locals = 0;
675 for (int index = 0; index < array->frames(); index++ ) {
676 // frame[number_of_frames - 1 ] = on_stack_size(youngest)
677 // frame[number_of_frames - 2 ] = on_stack_size(sender(youngest))
678 // frame[number_of_frames - 3 ] = on_stack_size(sender(sender(youngest)))
679 frame_sizes[number_of_frames - 1 - index] = BytesPerWord * array->element(index)->on_stack_size(callee_parameters,
680 callee_locals,
681 index == 0,
682 popframe_extra_args);
683 // This pc doesn't have to be perfect just good enough to identify the frame
684 // as interpreted so the skeleton frame will be walkable
685 // The correct pc will be set when the skeleton frame is completely filled out
686 // The final pc we store in the loop is wrong and will be overwritten below
687 frame_pcs[number_of_frames - 1 - index ] = Interpreter::deopt_entry(vtos, 0) - frame::pc_return_offset;
688
689 callee_parameters = array->element(index)->method()->size_of_parameters();
690 callee_locals = array->element(index)->method()->max_locals();
691 popframe_extra_args = 0;
692 }
693
694 // Compute whether the root vframe returns a float or double value.
695 BasicType return_type;
696 {
697 methodHandle method(current, array->element(0)->method());
698 Bytecode_invoke invoke = Bytecode_invoke_check(method, array->element(0)->bci());
699 return_type = invoke.is_valid() ? invoke.result_type() : T_ILLEGAL;
700 }
701
702 // Compute information for handling adapters and adjusting the frame size of the caller.
703 int caller_adjustment = 0;
704
705 // Compute the amount the oldest interpreter frame will have to adjust
706 // its caller's stack by. If the caller is a compiled frame then
707 // we pretend that the callee has no parameters so that the
708 // extension counts for the full amount of locals and not just
709 // locals-parms. This is because without a c2i adapter the parm
710 // area as created by the compiled frame will not be usable by
711 // the interpreter. (Depending on the calling convention there
712 // may not even be enough space).
713
714 // QQQ I'd rather see this pushed down into last_frame_adjust
715 // and have it take the sender (aka caller).
716
717 if (!deopt_sender.is_interpreted_frame() || caller_was_method_handle) {
718 caller_adjustment = last_frame_adjust(0, callee_locals);
719 } else if (callee_locals > callee_parameters) {
720 // The caller frame may need extending to accommodate
721 // non-parameter locals of the first unpacked interpreted frame.
722 // Compute that adjustment.
723 caller_adjustment = last_frame_adjust(callee_parameters, callee_locals);
724 }
725
726 // If the sender is deoptimized the we must retrieve the address of the handler
727 // since the frame will "magically" show the original pc before the deopt
728 // and we'd undo the deopt.
729
730 frame_pcs[0] = Continuation::is_cont_barrier_frame(deoptee) ? StubRoutines::cont_returnBarrier() : deopt_sender.raw_pc();
731 if (Continuation::is_continuation_enterSpecial(deopt_sender)) {
732 ContinuationEntry::from_frame(deopt_sender)->set_argsize(0);
733 }
734
735 assert(CodeCache::find_blob(frame_pcs[0]) != nullptr, "bad pc");
736
737 #if INCLUDE_JVMCI
738 if (exceptionObject() != nullptr) {
739 current->set_exception_oop(exceptionObject());
740 exec_mode = Unpack_exception;
741 }
742 #endif
743
744 if (current->frames_to_pop_failed_realloc() > 0 && exec_mode != Unpack_uncommon_trap) {
745 assert(current->has_pending_exception(), "should have thrown OOME");
746 current->set_exception_oop(current->pending_exception());
747 current->clear_pending_exception();
748 exec_mode = Unpack_exception;
749 }
750
751 #if INCLUDE_JVMCI
752 if (current->frames_to_pop_failed_realloc() > 0) {
753 current->set_pending_monitorenter(false);
754 }
755 #endif
756
757 UnrollBlock* info = new UnrollBlock(array->frame_size() * BytesPerWord,
758 caller_adjustment * BytesPerWord,
759 caller_was_method_handle ? 0 : callee_parameters,
760 number_of_frames,
761 frame_sizes,
762 frame_pcs,
763 return_type,
764 exec_mode);
765 // On some platforms, we need a way to pass some platform dependent
766 // information to the unpacking code so the skeletal frames come out
767 // correct (initial fp value, unextended sp, ...)
768 info->set_initial_info((intptr_t) array->sender().initial_deoptimization_info());
769
770 if (array->frames() > 1) {
771 if (VerifyStack && TraceDeoptimization) {
772 tty->print_cr("Deoptimizing method containing inlining");
773 }
774 }
775
776 array->set_unroll_block(info);
777 return info;
778 }
779
780 // Called to cleanup deoptimization data structures in normal case
781 // after unpacking to stack and when stack overflow error occurs
782 void Deoptimization::cleanup_deopt_info(JavaThread *thread,
783 vframeArray *array) {
784
785 // Get array if coming from exception
786 if (array == nullptr) {
787 array = thread->vframe_array_head();
788 }
789 thread->set_vframe_array_head(nullptr);
790
791 // Free the previous UnrollBlock
792 vframeArray* old_array = thread->vframe_array_last();
793 thread->set_vframe_array_last(array);
794
795 if (old_array != nullptr) {
796 UnrollBlock* old_info = old_array->unroll_block();
797 old_array->set_unroll_block(nullptr);
798 delete old_info;
799 delete old_array;
800 }
801
802 // Deallocate any resource creating in this routine and any ResourceObjs allocated
803 // inside the vframeArray (StackValueCollections)
804
805 delete thread->deopt_mark();
806 thread->set_deopt_mark(nullptr);
807 thread->set_deopt_compiled_method(nullptr);
808
809
810 if (JvmtiExport::can_pop_frame()) {
811 // Regardless of whether we entered this routine with the pending
812 // popframe condition bit set, we should always clear it now
813 thread->clear_popframe_condition();
814 }
815
816 // unpack_frames() is called at the end of the deoptimization handler
817 // and (in C2) at the end of the uncommon trap handler. Note this fact
818 // so that an asynchronous stack walker can work again. This counter is
819 // incremented at the beginning of fetch_unroll_info() and (in C2) at
820 // the beginning of uncommon_trap().
821 thread->dec_in_deopt_handler();
822 }
823
824 // Moved from cpu directories because none of the cpus has callee save values.
825 // If a cpu implements callee save values, move this to deoptimization_<cpu>.cpp.
826 void Deoptimization::unwind_callee_save_values(frame* f, vframeArray* vframe_array) {
827
828 // This code is sort of the equivalent of C2IAdapter::setup_stack_frame back in
829 // the days we had adapter frames. When we deoptimize a situation where a
830 // compiled caller calls a compiled caller will have registers it expects
831 // to survive the call to the callee. If we deoptimize the callee the only
832 // way we can restore these registers is to have the oldest interpreter
833 // frame that we create restore these values. That is what this routine
834 // will accomplish.
835
836 // At the moment we have modified c2 to not have any callee save registers
837 // so this problem does not exist and this routine is just a place holder.
838
839 assert(f->is_interpreted_frame(), "must be interpreted");
840 }
841
842 #ifndef PRODUCT
843 static bool falls_through(Bytecodes::Code bc) {
844 switch (bc) {
845 // List may be incomplete. Here we really only care about bytecodes where compiled code
846 // can deoptimize.
847 case Bytecodes::_goto:
848 case Bytecodes::_goto_w:
849 case Bytecodes::_athrow:
850 return false;
851 default:
852 return true;
853 }
854 }
855 #endif
856
857 // Return BasicType of value being returned
858 JRT_LEAF_PROF_NO_THREAD(BasicType, Deoptimization, unpack_frames, Deoptimization::unpack_frames(JavaThread* thread, int exec_mode))
859 assert(thread == JavaThread::current(), "pre-condition");
860
861 // We are already active in the special DeoptResourceMark any ResourceObj's we
862 // allocate will be freed at the end of the routine.
863
864 // JRT_LEAF methods don't normally allocate handles and there is a
865 // NoHandleMark to enforce that. It is actually safe to use Handles
866 // in a JRT_LEAF method, and sometimes desirable, but to do so we
867 // must use ResetNoHandleMark to bypass the NoHandleMark, and
868 // then use a HandleMark to ensure any Handles we do create are
869 // cleaned up in this scope.
870 ResetNoHandleMark rnhm;
871 HandleMark hm(thread);
872
873 frame stub_frame = thread->last_frame();
874
875 Continuation::notify_deopt(thread, stub_frame.sp());
876
877 // Since the frame to unpack is the top frame of this thread, the vframe_array_head
878 // must point to the vframeArray for the unpack frame.
879 vframeArray* array = thread->vframe_array_head();
880 UnrollBlock* info = array->unroll_block();
881
882 // We set the last_Java frame. But the stack isn't really parsable here. So we
883 // clear it to make sure JFR understands not to try and walk stacks from events
884 // in here.
885 intptr_t* sp = thread->frame_anchor()->last_Java_sp();
886 thread->frame_anchor()->set_last_Java_sp(nullptr);
887
888 // Unpack the interpreter frames and any adapter frame (c2 only) we might create.
889 array->unpack_to_stack(stub_frame, exec_mode, info->caller_actual_parameters());
890
891 thread->frame_anchor()->set_last_Java_sp(sp);
892
893 BasicType bt = info->return_type();
894
895 // If we have an exception pending, claim that the return type is an oop
896 // so the deopt_blob does not overwrite the exception_oop.
897
898 if (exec_mode == Unpack_exception)
899 bt = T_OBJECT;
900
901 // Cleanup thread deopt data
902 cleanup_deopt_info(thread, array);
903
904 #ifndef PRODUCT
905 if (VerifyStack) {
906 ResourceMark res_mark;
907 // Clear pending exception to not break verification code (restored afterwards)
908 PreserveExceptionMark pm(thread);
909
910 thread->validate_frame_layout();
911
912 // Verify that the just-unpacked frames match the interpreter's
913 // notions of expression stack and locals
914 vframeArray* cur_array = thread->vframe_array_last();
915 RegisterMap rm(thread,
916 RegisterMap::UpdateMap::skip,
917 RegisterMap::ProcessFrames::include,
918 RegisterMap::WalkContinuation::skip);
919 rm.set_include_argument_oops(false);
920 bool is_top_frame = true;
921 int callee_size_of_parameters = 0;
922 int callee_max_locals = 0;
923 for (int i = 0; i < cur_array->frames(); i++) {
924 vframeArrayElement* el = cur_array->element(i);
925 frame* iframe = el->iframe();
926 guarantee(iframe->is_interpreted_frame(), "Wrong frame type");
927
928 // Get the oop map for this bci
929 InterpreterOopMap mask;
930 int cur_invoke_parameter_size = 0;
931 bool try_next_mask = false;
932 int next_mask_expression_stack_size = -1;
933 int top_frame_expression_stack_adjustment = 0;
934 methodHandle mh(thread, iframe->interpreter_frame_method());
935 OopMapCache::compute_one_oop_map(mh, iframe->interpreter_frame_bci(), &mask);
936 BytecodeStream str(mh, iframe->interpreter_frame_bci());
937 int max_bci = mh->code_size();
938 // Get to the next bytecode if possible
939 assert(str.bci() < max_bci, "bci in interpreter frame out of bounds");
940 // Check to see if we can grab the number of outgoing arguments
941 // at an uncommon trap for an invoke (where the compiler
942 // generates debug info before the invoke has executed)
943 Bytecodes::Code cur_code = str.next();
944 Bytecodes::Code next_code = Bytecodes::_shouldnotreachhere;
945 if (Bytecodes::is_invoke(cur_code)) {
946 Bytecode_invoke invoke(mh, iframe->interpreter_frame_bci());
947 cur_invoke_parameter_size = invoke.size_of_parameters();
948 if (i != 0 && !invoke.is_invokedynamic() && MethodHandles::has_member_arg(invoke.klass(), invoke.name())) {
949 callee_size_of_parameters++;
950 }
951 }
952 if (str.bci() < max_bci) {
953 next_code = str.next();
954 if (next_code >= 0) {
955 // The interpreter oop map generator reports results before
956 // the current bytecode has executed except in the case of
957 // calls. It seems to be hard to tell whether the compiler
958 // has emitted debug information matching the "state before"
959 // a given bytecode or the state after, so we try both
960 if (!Bytecodes::is_invoke(cur_code) && falls_through(cur_code)) {
961 // Get expression stack size for the next bytecode
962 InterpreterOopMap next_mask;
963 OopMapCache::compute_one_oop_map(mh, str.bci(), &next_mask);
964 next_mask_expression_stack_size = next_mask.expression_stack_size();
965 if (Bytecodes::is_invoke(next_code)) {
966 Bytecode_invoke invoke(mh, str.bci());
967 next_mask_expression_stack_size += invoke.size_of_parameters();
968 }
969 // Need to subtract off the size of the result type of
970 // the bytecode because this is not described in the
971 // debug info but returned to the interpreter in the TOS
972 // caching register
973 BasicType bytecode_result_type = Bytecodes::result_type(cur_code);
974 if (bytecode_result_type != T_ILLEGAL) {
975 top_frame_expression_stack_adjustment = type2size[bytecode_result_type];
976 }
977 assert(top_frame_expression_stack_adjustment >= 0, "stack adjustment must be positive");
978 try_next_mask = true;
979 }
980 }
981 }
982
983 // Verify stack depth and oops in frame
984 // This assertion may be dependent on the platform we're running on and may need modification (tested on x86 and sparc)
985 if (!(
986 /* SPARC */
987 (iframe->interpreter_frame_expression_stack_size() == mask.expression_stack_size() + callee_size_of_parameters) ||
988 /* x86 */
989 (iframe->interpreter_frame_expression_stack_size() == mask.expression_stack_size() + callee_max_locals) ||
990 (try_next_mask &&
991 (iframe->interpreter_frame_expression_stack_size() == (next_mask_expression_stack_size -
992 top_frame_expression_stack_adjustment))) ||
993 (is_top_frame && (exec_mode == Unpack_exception) && iframe->interpreter_frame_expression_stack_size() == 0) ||
994 (is_top_frame && (exec_mode == Unpack_uncommon_trap || exec_mode == Unpack_reexecute || el->should_reexecute()) &&
995 (iframe->interpreter_frame_expression_stack_size() == mask.expression_stack_size() + cur_invoke_parameter_size))
996 )) {
997 {
998 // Print out some information that will help us debug the problem
999 tty->print_cr("Wrong number of expression stack elements during deoptimization");
1000 tty->print_cr(" Error occurred while verifying frame %d (0..%d, 0 is topmost)", i, cur_array->frames() - 1);
1001 tty->print_cr(" Current code %s", Bytecodes::name(cur_code));
1002 if (try_next_mask) {
1003 tty->print_cr(" Next code %s", Bytecodes::name(next_code));
1004 }
1005 tty->print_cr(" Fabricated interpreter frame had %d expression stack elements",
1006 iframe->interpreter_frame_expression_stack_size());
1007 tty->print_cr(" Interpreter oop map had %d expression stack elements", mask.expression_stack_size());
1008 tty->print_cr(" try_next_mask = %d", try_next_mask);
1009 tty->print_cr(" next_mask_expression_stack_size = %d", next_mask_expression_stack_size);
1010 tty->print_cr(" callee_size_of_parameters = %d", callee_size_of_parameters);
1011 tty->print_cr(" callee_max_locals = %d", callee_max_locals);
1012 tty->print_cr(" top_frame_expression_stack_adjustment = %d", top_frame_expression_stack_adjustment);
1013 tty->print_cr(" exec_mode = %d", exec_mode);
1014 tty->print_cr(" cur_invoke_parameter_size = %d", cur_invoke_parameter_size);
1015 tty->print_cr(" Thread = " INTPTR_FORMAT ", thread ID = %d", p2i(thread), thread->osthread()->thread_id());
1016 tty->print_cr(" Interpreted frames:");
1017 for (int k = 0; k < cur_array->frames(); k++) {
1018 vframeArrayElement* el = cur_array->element(k);
1019 tty->print_cr(" %s (bci %d)", el->method()->name_and_sig_as_C_string(), el->bci());
1020 }
1021 cur_array->print_on_2(tty);
1022 }
1023 guarantee(false, "wrong number of expression stack elements during deopt");
1024 }
1025 VerifyOopClosure verify;
1026 iframe->oops_interpreted_do(&verify, &rm, false);
1027 callee_size_of_parameters = mh->size_of_parameters();
1028 callee_max_locals = mh->max_locals();
1029 is_top_frame = false;
1030 }
1031 }
1032 #endif // !PRODUCT
1033
1034 return bt;
1035 JRT_END
1036
1037 class DeoptimizeMarkedClosure : public HandshakeClosure {
1038 public:
1039 DeoptimizeMarkedClosure() : HandshakeClosure("Deoptimize") {}
1040 void do_thread(Thread* thread) {
1041 JavaThread* jt = JavaThread::cast(thread);
1042 jt->deoptimize_marked_methods();
1043 }
1044 };
1045
1046 void Deoptimization::deoptimize_all_marked() {
1047 ResourceMark rm;
1048
1049 // Make the dependent methods not entrant
1050 CodeCache::make_marked_nmethods_deoptimized();
1051
1052 DeoptimizeMarkedClosure deopt;
1053 if (SafepointSynchronize::is_at_safepoint()) {
1054 Threads::java_threads_do(&deopt);
1055 } else {
1056 Handshake::execute(&deopt);
1057 }
1058 }
1059
1060 Deoptimization::DeoptAction Deoptimization::_unloaded_action
1061 = Deoptimization::Action_reinterpret;
1062
1063 #if INCLUDE_JVMCI
1064 template<typename CacheType>
1065 class BoxCacheBase : public CHeapObj<mtCompiler> {
1066 protected:
1067 static InstanceKlass* find_cache_klass(Thread* thread, Symbol* klass_name) {
1068 ResourceMark rm(thread);
1069 char* klass_name_str = klass_name->as_C_string();
1070 InstanceKlass* ik = SystemDictionary::find_instance_klass(thread, klass_name, Handle(), Handle());
1071 guarantee(ik != nullptr, "%s must be loaded", klass_name_str);
1072 if (!ik->is_in_error_state()) {
1073 guarantee(ik->is_initialized(), "%s must be initialized", klass_name_str);
1074 CacheType::compute_offsets(ik);
1075 }
1076 return ik;
1077 }
1078 };
1079
1080 template<typename PrimitiveType, typename CacheType, typename BoxType> class BoxCache : public BoxCacheBase<CacheType> {
1081 PrimitiveType _low;
1082 PrimitiveType _high;
1083 jobject _cache;
1084 protected:
1085 static BoxCache<PrimitiveType, CacheType, BoxType> *_singleton;
1086 BoxCache(Thread* thread) {
1087 InstanceKlass* ik = BoxCacheBase<CacheType>::find_cache_klass(thread, CacheType::symbol());
1088 if (ik->is_in_error_state()) {
1089 _low = 1;
1090 _high = 0;
1091 _cache = nullptr;
1092 } else {
1093 objArrayOop cache = CacheType::cache(ik);
1094 assert(cache->length() > 0, "Empty cache");
1095 _low = BoxType::value(cache->obj_at(0));
1096 _high = checked_cast<PrimitiveType>(_low + cache->length() - 1);
1097 _cache = JNIHandles::make_global(Handle(thread, cache));
1098 }
1099 }
1100 ~BoxCache() {
1101 JNIHandles::destroy_global(_cache);
1102 }
1103 public:
1104 static BoxCache<PrimitiveType, CacheType, BoxType>* singleton(Thread* thread) {
1105 if (_singleton == nullptr) {
1106 BoxCache<PrimitiveType, CacheType, BoxType>* s = new BoxCache<PrimitiveType, CacheType, BoxType>(thread);
1107 if (!Atomic::replace_if_null(&_singleton, s)) {
1108 delete s;
1109 }
1110 }
1111 return _singleton;
1112 }
1113 oop lookup(PrimitiveType value) {
1114 if (_low <= value && value <= _high) {
1115 int offset = checked_cast<int>(value - _low);
1116 return objArrayOop(JNIHandles::resolve_non_null(_cache))->obj_at(offset);
1117 }
1118 return nullptr;
1119 }
1120 oop lookup_raw(intptr_t raw_value, bool& cache_init_error) {
1121 if (_cache == nullptr) {
1122 cache_init_error = true;
1123 return nullptr;
1124 }
1125 // Have to cast to avoid little/big-endian problems.
1126 if (sizeof(PrimitiveType) > sizeof(jint)) {
1127 jlong value = (jlong)raw_value;
1128 return lookup(value);
1129 }
1130 PrimitiveType value = (PrimitiveType)*((jint*)&raw_value);
1131 return lookup(value);
1132 }
1133 };
1134
1135 typedef BoxCache<jint, java_lang_Integer_IntegerCache, java_lang_Integer> IntegerBoxCache;
1136 typedef BoxCache<jlong, java_lang_Long_LongCache, java_lang_Long> LongBoxCache;
1137 typedef BoxCache<jchar, java_lang_Character_CharacterCache, java_lang_Character> CharacterBoxCache;
1138 typedef BoxCache<jshort, java_lang_Short_ShortCache, java_lang_Short> ShortBoxCache;
1139 typedef BoxCache<jbyte, java_lang_Byte_ByteCache, java_lang_Byte> ByteBoxCache;
1140
1141 template<> BoxCache<jint, java_lang_Integer_IntegerCache, java_lang_Integer>* BoxCache<jint, java_lang_Integer_IntegerCache, java_lang_Integer>::_singleton = nullptr;
1142 template<> BoxCache<jlong, java_lang_Long_LongCache, java_lang_Long>* BoxCache<jlong, java_lang_Long_LongCache, java_lang_Long>::_singleton = nullptr;
1143 template<> BoxCache<jchar, java_lang_Character_CharacterCache, java_lang_Character>* BoxCache<jchar, java_lang_Character_CharacterCache, java_lang_Character>::_singleton = nullptr;
1144 template<> BoxCache<jshort, java_lang_Short_ShortCache, java_lang_Short>* BoxCache<jshort, java_lang_Short_ShortCache, java_lang_Short>::_singleton = nullptr;
1145 template<> BoxCache<jbyte, java_lang_Byte_ByteCache, java_lang_Byte>* BoxCache<jbyte, java_lang_Byte_ByteCache, java_lang_Byte>::_singleton = nullptr;
1146
1147 class BooleanBoxCache : public BoxCacheBase<java_lang_Boolean> {
1148 jobject _true_cache;
1149 jobject _false_cache;
1150 protected:
1151 static BooleanBoxCache *_singleton;
1152 BooleanBoxCache(Thread *thread) {
1153 InstanceKlass* ik = find_cache_klass(thread, java_lang_Boolean::symbol());
1154 if (ik->is_in_error_state()) {
1155 _true_cache = nullptr;
1156 _false_cache = nullptr;
1157 } else {
1158 _true_cache = JNIHandles::make_global(Handle(thread, java_lang_Boolean::get_TRUE(ik)));
1159 _false_cache = JNIHandles::make_global(Handle(thread, java_lang_Boolean::get_FALSE(ik)));
1160 }
1161 }
1162 ~BooleanBoxCache() {
1163 JNIHandles::destroy_global(_true_cache);
1164 JNIHandles::destroy_global(_false_cache);
1165 }
1166 public:
1167 static BooleanBoxCache* singleton(Thread* thread) {
1168 if (_singleton == nullptr) {
1169 BooleanBoxCache* s = new BooleanBoxCache(thread);
1170 if (!Atomic::replace_if_null(&_singleton, s)) {
1171 delete s;
1172 }
1173 }
1174 return _singleton;
1175 }
1176 oop lookup_raw(intptr_t raw_value, bool& cache_in_error) {
1177 if (_true_cache == nullptr) {
1178 cache_in_error = true;
1179 return nullptr;
1180 }
1181 // Have to cast to avoid little/big-endian problems.
1182 jboolean value = (jboolean)*((jint*)&raw_value);
1183 return lookup(value);
1184 }
1185 oop lookup(jboolean value) {
1186 if (value != 0) {
1187 return JNIHandles::resolve_non_null(_true_cache);
1188 }
1189 return JNIHandles::resolve_non_null(_false_cache);
1190 }
1191 };
1192
1193 BooleanBoxCache* BooleanBoxCache::_singleton = nullptr;
1194
1195 oop Deoptimization::get_cached_box(AutoBoxObjectValue* bv, frame* fr, RegisterMap* reg_map, bool& cache_init_error, TRAPS) {
1196 Klass* k = java_lang_Class::as_Klass(bv->klass()->as_ConstantOopReadValue()->value()());
1197 BasicType box_type = vmClasses::box_klass_type(k);
1198 if (box_type != T_OBJECT) {
1199 StackValue* value = StackValue::create_stack_value(fr, reg_map, bv->field_at(box_type == T_LONG ? 1 : 0));
1200 switch(box_type) {
1201 case T_INT: return IntegerBoxCache::singleton(THREAD)->lookup_raw(value->get_intptr(), cache_init_error);
1202 case T_CHAR: return CharacterBoxCache::singleton(THREAD)->lookup_raw(value->get_intptr(), cache_init_error);
1203 case T_SHORT: return ShortBoxCache::singleton(THREAD)->lookup_raw(value->get_intptr(), cache_init_error);
1204 case T_BYTE: return ByteBoxCache::singleton(THREAD)->lookup_raw(value->get_intptr(), cache_init_error);
1205 case T_BOOLEAN: return BooleanBoxCache::singleton(THREAD)->lookup_raw(value->get_intptr(), cache_init_error);
1206 case T_LONG: return LongBoxCache::singleton(THREAD)->lookup_raw(value->get_intptr(), cache_init_error);
1207 default:;
1208 }
1209 }
1210 return nullptr;
1211 }
1212 #endif // INCLUDE_JVMCI
1213
1214 #if COMPILER2_OR_JVMCI
1215 bool Deoptimization::realloc_objects(JavaThread* thread, frame* fr, RegisterMap* reg_map, GrowableArray<ScopeValue*>* objects, TRAPS) {
1216 Handle pending_exception(THREAD, thread->pending_exception());
1217 const char* exception_file = thread->exception_file();
1218 int exception_line = thread->exception_line();
1219 thread->clear_pending_exception();
1220
1221 bool failures = false;
1222
1223 for (int i = 0; i < objects->length(); i++) {
1224 assert(objects->at(i)->is_object(), "invalid debug information");
1225 ObjectValue* sv = (ObjectValue*) objects->at(i);
1226
1227 Klass* k = java_lang_Class::as_Klass(sv->klass()->as_ConstantOopReadValue()->value()());
1228 oop obj = nullptr;
1229
1230 bool cache_init_error = false;
1231 if (k->is_instance_klass()) {
1232 #if INCLUDE_JVMCI
1233 nmethod* nm = fr->cb()->as_nmethod_or_null();
1234 if (nm->is_compiled_by_jvmci() && sv->is_auto_box()) {
1235 AutoBoxObjectValue* abv = (AutoBoxObjectValue*) sv;
1236 obj = get_cached_box(abv, fr, reg_map, cache_init_error, THREAD);
1237 if (obj != nullptr) {
1238 // Set the flag to indicate the box came from a cache, so that we can skip the field reassignment for it.
1239 abv->set_cached(true);
1240 } else if (cache_init_error) {
1241 // Results in an OOME which is valid (as opposed to a class initialization error)
1242 // and is fine for the rare case a cache initialization failing.
1243 failures = true;
1244 }
1245 }
1246 #endif // INCLUDE_JVMCI
1247
1248 InstanceKlass* ik = InstanceKlass::cast(k);
1249 if (obj == nullptr && !cache_init_error) {
1250 InternalOOMEMark iom(THREAD);
1251 if (EnableVectorSupport && VectorSupport::is_vector(ik)) {
1252 obj = VectorSupport::allocate_vector(ik, fr, reg_map, sv, THREAD);
1253 } else {
1254 obj = ik->allocate_instance(THREAD);
1255 }
1256 }
1257 } else if (k->is_typeArray_klass()) {
1258 TypeArrayKlass* ak = TypeArrayKlass::cast(k);
1259 assert(sv->field_size() % type2size[ak->element_type()] == 0, "non-integral array length");
1260 int len = sv->field_size() / type2size[ak->element_type()];
1261 InternalOOMEMark iom(THREAD);
1262 obj = ak->allocate(len, THREAD);
1263 } else if (k->is_objArray_klass()) {
1264 ObjArrayKlass* ak = ObjArrayKlass::cast(k);
1265 InternalOOMEMark iom(THREAD);
1266 obj = ak->allocate(sv->field_size(), THREAD);
1267 }
1268
1269 if (obj == nullptr) {
1270 failures = true;
1271 }
1272
1273 assert(sv->value().is_null(), "redundant reallocation");
1274 assert(obj != nullptr || HAS_PENDING_EXCEPTION || cache_init_error, "allocation should succeed or we should get an exception");
1275 CLEAR_PENDING_EXCEPTION;
1276 sv->set_value(obj);
1277 }
1278
1279 if (failures) {
1280 THROW_OOP_(Universe::out_of_memory_error_realloc_objects(), failures);
1281 } else if (pending_exception.not_null()) {
1282 thread->set_pending_exception(pending_exception(), exception_file, exception_line);
1283 }
1284
1285 return failures;
1286 }
1287
1288 #if INCLUDE_JVMCI
1289 /**
1290 * For primitive types whose kind gets "erased" at runtime (shorts become stack ints),
1291 * we need to somehow be able to recover the actual kind to be able to write the correct
1292 * amount of bytes.
1293 * For that purpose, this method assumes that, for an entry spanning n bytes at index i,
1294 * the entries at index n + 1 to n + i are 'markers'.
1295 * For example, if we were writing a short at index 4 of a byte array of size 8, the
1296 * expected form of the array would be:
1297 *
1298 * {b0, b1, b2, b3, INT, marker, b6, b7}
1299 *
1300 * Thus, in order to get back the size of the entry, we simply need to count the number
1301 * of marked entries
1302 *
1303 * @param virtualArray the virtualized byte array
1304 * @param i index of the virtual entry we are recovering
1305 * @return The number of bytes the entry spans
1306 */
1307 static int count_number_of_bytes_for_entry(ObjectValue *virtualArray, int i) {
1308 int index = i;
1309 while (++index < virtualArray->field_size() &&
1310 virtualArray->field_at(index)->is_marker()) {}
1311 return index - i;
1312 }
1313
1314 /**
1315 * If there was a guarantee for byte array to always start aligned to a long, we could
1316 * do a simple check on the parity of the index. Unfortunately, that is not always the
1317 * case. Thus, we check alignment of the actual address we are writing to.
1318 * In the unlikely case index 0 is 5-aligned for example, it would then be possible to
1319 * write a long to index 3.
1320 */
1321 static jbyte* check_alignment_get_addr(typeArrayOop obj, int index, int expected_alignment) {
1322 jbyte* res = obj->byte_at_addr(index);
1323 assert((((intptr_t) res) % expected_alignment) == 0, "Non-aligned write");
1324 return res;
1325 }
1326
1327 static void byte_array_put(typeArrayOop obj, StackValue* value, int index, int byte_count) {
1328 switch (byte_count) {
1329 case 1:
1330 obj->byte_at_put(index, (jbyte) value->get_jint());
1331 break;
1332 case 2:
1333 *((jshort *) check_alignment_get_addr(obj, index, 2)) = (jshort) value->get_jint();
1334 break;
1335 case 4:
1336 *((jint *) check_alignment_get_addr(obj, index, 4)) = value->get_jint();
1337 break;
1338 case 8:
1339 *((jlong *) check_alignment_get_addr(obj, index, 8)) = (jlong) value->get_intptr();
1340 break;
1341 default:
1342 ShouldNotReachHere();
1343 }
1344 }
1345 #endif // INCLUDE_JVMCI
1346
1347
1348 // restore elements of an eliminated type array
1349 void Deoptimization::reassign_type_array_elements(frame* fr, RegisterMap* reg_map, ObjectValue* sv, typeArrayOop obj, BasicType type) {
1350 int index = 0;
1351
1352 for (int i = 0; i < sv->field_size(); i++) {
1353 StackValue* value = StackValue::create_stack_value(fr, reg_map, sv->field_at(i));
1354 switch(type) {
1355 case T_LONG: case T_DOUBLE: {
1356 assert(value->type() == T_INT, "Agreement.");
1357 StackValue* low =
1358 StackValue::create_stack_value(fr, reg_map, sv->field_at(++i));
1359 #ifdef _LP64
1360 jlong res = (jlong)low->get_intptr();
1361 #else
1362 jlong res = jlong_from(value->get_jint(), low->get_jint());
1363 #endif
1364 obj->long_at_put(index, res);
1365 break;
1366 }
1367
1368 case T_INT: case T_FLOAT: { // 4 bytes.
1369 assert(value->type() == T_INT, "Agreement.");
1370 bool big_value = false;
1371 if (i + 1 < sv->field_size() && type == T_INT) {
1372 if (sv->field_at(i)->is_location()) {
1373 Location::Type type = ((LocationValue*) sv->field_at(i))->location().type();
1374 if (type == Location::dbl || type == Location::lng) {
1375 big_value = true;
1376 }
1377 } else if (sv->field_at(i)->is_constant_int()) {
1378 ScopeValue* next_scope_field = sv->field_at(i + 1);
1379 if (next_scope_field->is_constant_long() || next_scope_field->is_constant_double()) {
1380 big_value = true;
1381 }
1382 }
1383 }
1384
1385 if (big_value) {
1386 StackValue* low = StackValue::create_stack_value(fr, reg_map, sv->field_at(++i));
1387 #ifdef _LP64
1388 jlong res = (jlong)low->get_intptr();
1389 #else
1390 jlong res = jlong_from(value->get_jint(), low->get_jint());
1391 #endif
1392 obj->int_at_put(index, *(jint*)&res);
1393 obj->int_at_put(++index, *((jint*)&res + 1));
1394 } else {
1395 obj->int_at_put(index, value->get_jint());
1396 }
1397 break;
1398 }
1399
1400 case T_SHORT:
1401 assert(value->type() == T_INT, "Agreement.");
1402 obj->short_at_put(index, (jshort)value->get_jint());
1403 break;
1404
1405 case T_CHAR:
1406 assert(value->type() == T_INT, "Agreement.");
1407 obj->char_at_put(index, (jchar)value->get_jint());
1408 break;
1409
1410 case T_BYTE: {
1411 assert(value->type() == T_INT, "Agreement.");
1412 #if INCLUDE_JVMCI
1413 // The value we get is erased as a regular int. We will need to find its actual byte count 'by hand'.
1414 int byte_count = count_number_of_bytes_for_entry(sv, i);
1415 byte_array_put(obj, value, index, byte_count);
1416 // According to byte_count contract, the values from i + 1 to i + byte_count are illegal values. Skip.
1417 i += byte_count - 1; // Balance the loop counter.
1418 index += byte_count;
1419 // index has been updated so continue at top of loop
1420 continue;
1421 #else
1422 obj->byte_at_put(index, (jbyte)value->get_jint());
1423 break;
1424 #endif // INCLUDE_JVMCI
1425 }
1426
1427 case T_BOOLEAN: {
1428 assert(value->type() == T_INT, "Agreement.");
1429 obj->bool_at_put(index, (jboolean)value->get_jint());
1430 break;
1431 }
1432
1433 default:
1434 ShouldNotReachHere();
1435 }
1436 index++;
1437 }
1438 }
1439
1440 // restore fields of an eliminated object array
1441 void Deoptimization::reassign_object_array_elements(frame* fr, RegisterMap* reg_map, ObjectValue* sv, objArrayOop obj) {
1442 for (int i = 0; i < sv->field_size(); i++) {
1443 StackValue* value = StackValue::create_stack_value(fr, reg_map, sv->field_at(i));
1444 assert(value->type() == T_OBJECT, "object element expected");
1445 obj->obj_at_put(i, value->get_obj()());
1446 }
1447 }
1448
1449 class ReassignedField {
1450 public:
1451 int _offset;
1452 BasicType _type;
1453 public:
1454 ReassignedField() {
1455 _offset = 0;
1456 _type = T_ILLEGAL;
1457 }
1458 };
1459
1460 static int compare(ReassignedField* left, ReassignedField* right) {
1461 return left->_offset - right->_offset;
1462 }
1463
1464 // Restore fields of an eliminated instance object using the same field order
1465 // returned by HotSpotResolvedObjectTypeImpl.getInstanceFields(true)
1466 static int reassign_fields_by_klass(InstanceKlass* klass, frame* fr, RegisterMap* reg_map, ObjectValue* sv, int svIndex, oop obj, bool skip_internal) {
1467 GrowableArray<ReassignedField>* fields = new GrowableArray<ReassignedField>();
1468 InstanceKlass* ik = klass;
1469 while (ik != nullptr) {
1470 for (AllFieldStream fs(ik); !fs.done(); fs.next()) {
1471 if (!fs.access_flags().is_static() && (!skip_internal || !fs.field_flags().is_injected())) {
1472 ReassignedField field;
1473 field._offset = fs.offset();
1474 field._type = Signature::basic_type(fs.signature());
1475 fields->append(field);
1476 }
1477 }
1478 ik = ik->superklass();
1479 }
1480 fields->sort(compare);
1481 for (int i = 0; i < fields->length(); i++) {
1482 ScopeValue* scope_field = sv->field_at(svIndex);
1483 StackValue* value = StackValue::create_stack_value(fr, reg_map, scope_field);
1484 int offset = fields->at(i)._offset;
1485 BasicType type = fields->at(i)._type;
1486 switch (type) {
1487 case T_OBJECT: case T_ARRAY:
1488 assert(value->type() == T_OBJECT, "Agreement.");
1489 obj->obj_field_put(offset, value->get_obj()());
1490 break;
1491
1492 case T_INT: case T_FLOAT: { // 4 bytes.
1493 assert(value->type() == T_INT, "Agreement.");
1494 bool big_value = false;
1495 if (i+1 < fields->length() && fields->at(i+1)._type == T_INT) {
1496 if (scope_field->is_location()) {
1497 Location::Type type = ((LocationValue*) scope_field)->location().type();
1498 if (type == Location::dbl || type == Location::lng) {
1499 big_value = true;
1500 }
1501 }
1502 if (scope_field->is_constant_int()) {
1503 ScopeValue* next_scope_field = sv->field_at(svIndex + 1);
1504 if (next_scope_field->is_constant_long() || next_scope_field->is_constant_double()) {
1505 big_value = true;
1506 }
1507 }
1508 }
1509
1510 if (big_value) {
1511 i++;
1512 assert(i < fields->length(), "second T_INT field needed");
1513 assert(fields->at(i)._type == T_INT, "T_INT field needed");
1514 } else {
1515 obj->int_field_put(offset, value->get_jint());
1516 break;
1517 }
1518 }
1519 /* no break */
1520
1521 case T_LONG: case T_DOUBLE: {
1522 assert(value->type() == T_INT, "Agreement.");
1523 StackValue* low = StackValue::create_stack_value(fr, reg_map, sv->field_at(++svIndex));
1524 #ifdef _LP64
1525 jlong res = (jlong)low->get_intptr();
1526 #else
1527 jlong res = jlong_from(value->get_jint(), low->get_jint());
1528 #endif
1529 obj->long_field_put(offset, res);
1530 break;
1531 }
1532
1533 case T_SHORT:
1534 assert(value->type() == T_INT, "Agreement.");
1535 obj->short_field_put(offset, (jshort)value->get_jint());
1536 break;
1537
1538 case T_CHAR:
1539 assert(value->type() == T_INT, "Agreement.");
1540 obj->char_field_put(offset, (jchar)value->get_jint());
1541 break;
1542
1543 case T_BYTE:
1544 assert(value->type() == T_INT, "Agreement.");
1545 obj->byte_field_put(offset, (jbyte)value->get_jint());
1546 break;
1547
1548 case T_BOOLEAN:
1549 assert(value->type() == T_INT, "Agreement.");
1550 obj->bool_field_put(offset, (jboolean)value->get_jint());
1551 break;
1552
1553 default:
1554 ShouldNotReachHere();
1555 }
1556 svIndex++;
1557 }
1558 return svIndex;
1559 }
1560
1561 // restore fields of all eliminated objects and arrays
1562 void Deoptimization::reassign_fields(frame* fr, RegisterMap* reg_map, GrowableArray<ScopeValue*>* objects, bool realloc_failures, bool skip_internal) {
1563 for (int i = 0; i < objects->length(); i++) {
1564 assert(objects->at(i)->is_object(), "invalid debug information");
1565 ObjectValue* sv = (ObjectValue*) objects->at(i);
1566 Klass* k = java_lang_Class::as_Klass(sv->klass()->as_ConstantOopReadValue()->value()());
1567 Handle obj = sv->value();
1568 assert(obj.not_null() || realloc_failures, "reallocation was missed");
1569 #ifndef PRODUCT
1570 if (PrintDeoptimizationDetails) {
1571 tty->print_cr("reassign fields for object of type %s!", k->name()->as_C_string());
1572 }
1573 #endif // !PRODUCT
1574
1575 if (obj.is_null()) {
1576 continue;
1577 }
1578
1579 #if INCLUDE_JVMCI
1580 // Don't reassign fields of boxes that came from a cache. Caches may be in CDS.
1581 if (sv->is_auto_box() && ((AutoBoxObjectValue*) sv)->is_cached()) {
1582 continue;
1583 }
1584 #endif // INCLUDE_JVMCI
1585 if (EnableVectorSupport && VectorSupport::is_vector(k)) {
1586 assert(sv->field_size() == 1, "%s not a vector", k->name()->as_C_string());
1587 ScopeValue* payload = sv->field_at(0);
1588 if (payload->is_location() &&
1589 payload->as_LocationValue()->location().type() == Location::vector) {
1590 #ifndef PRODUCT
1591 if (PrintDeoptimizationDetails) {
1592 tty->print_cr("skip field reassignment for this vector - it should be assigned already");
1593 if (Verbose) {
1594 Handle obj = sv->value();
1595 k->oop_print_on(obj(), tty);
1596 }
1597 }
1598 #endif // !PRODUCT
1599 continue; // Such vector's value was already restored in VectorSupport::allocate_vector().
1600 }
1601 // Else fall-through to do assignment for scalar-replaced boxed vector representation
1602 // which could be restored after vector object allocation.
1603 }
1604 if (k->is_instance_klass()) {
1605 InstanceKlass* ik = InstanceKlass::cast(k);
1606 reassign_fields_by_klass(ik, fr, reg_map, sv, 0, obj(), skip_internal);
1607 } else if (k->is_typeArray_klass()) {
1608 TypeArrayKlass* ak = TypeArrayKlass::cast(k);
1609 reassign_type_array_elements(fr, reg_map, sv, (typeArrayOop) obj(), ak->element_type());
1610 } else if (k->is_objArray_klass()) {
1611 reassign_object_array_elements(fr, reg_map, sv, (objArrayOop) obj());
1612 }
1613 }
1614 // These objects may escape when we return to Interpreter after deoptimization.
1615 // We need barrier so that stores that initialize these objects can't be reordered
1616 // with subsequent stores that make these objects accessible by other threads.
1617 OrderAccess::storestore();
1618 }
1619
1620
1621 // relock objects for which synchronization was eliminated
1622 bool Deoptimization::relock_objects(JavaThread* thread, GrowableArray<MonitorInfo*>* monitors,
1623 JavaThread* deoptee_thread, frame& fr, int exec_mode, bool realloc_failures) {
1624 bool relocked_objects = false;
1625 for (int i = 0; i < monitors->length(); i++) {
1626 MonitorInfo* mon_info = monitors->at(i);
1627 if (mon_info->eliminated()) {
1628 assert(!mon_info->owner_is_scalar_replaced() || realloc_failures, "reallocation was missed");
1629 relocked_objects = true;
1630 if (!mon_info->owner_is_scalar_replaced()) {
1631 Handle obj(thread, mon_info->owner());
1632 markWord mark = obj->mark();
1633 if (exec_mode == Unpack_none) {
1634 if (LockingMode == LM_LEGACY && mark.has_locker() && fr.sp() > (intptr_t*)mark.locker()) {
1635 // With exec_mode == Unpack_none obj may be thread local and locked in
1636 // a callee frame. Make the lock in the callee a recursive lock and restore the displaced header.
1637 markWord dmw = mark.displaced_mark_helper();
1638 mark.locker()->set_displaced_header(markWord::encode((BasicLock*) nullptr));
1639 obj->set_mark(dmw);
1640 }
1641 if (mark.has_monitor()) {
1642 // defer relocking if the deoptee thread is currently waiting for obj
1643 ObjectMonitor* waiting_monitor = deoptee_thread->current_waiting_monitor();
1644 if (waiting_monitor != nullptr && waiting_monitor->object() == obj()) {
1645 assert(fr.is_deoptimized_frame(), "frame must be scheduled for deoptimization");
1646 if (LockingMode == LM_LEGACY) {
1647 mon_info->lock()->set_displaced_header(markWord::unused_mark());
1648 } else if (UseObjectMonitorTable) {
1649 mon_info->lock()->clear_object_monitor_cache();
1650 }
1651 #ifdef ASSERT
1652 else {
1653 assert(LockingMode == LM_MONITOR || !UseObjectMonitorTable, "must be");
1654 mon_info->lock()->set_bad_metadata_deopt();
1655 }
1656 #endif
1657 JvmtiDeferredUpdates::inc_relock_count_after_wait(deoptee_thread);
1658 continue;
1659 }
1660 }
1661 }
1662 BasicLock* lock = mon_info->lock();
1663 if (LockingMode == LM_LIGHTWEIGHT) {
1664 // We have lost information about the correct state of the lock stack.
1665 // Entering may create an invalid lock stack. Inflate the lock if it
1666 // was fast_locked to restore the valid lock stack.
1667 ObjectSynchronizer::enter_for(obj, lock, deoptee_thread);
1668 if (deoptee_thread->lock_stack().contains(obj())) {
1669 LightweightSynchronizer::inflate_fast_locked_object(obj(), ObjectSynchronizer::InflateCause::inflate_cause_vm_internal,
1670 deoptee_thread, thread);
1671 }
1672 assert(mon_info->owner()->is_locked(), "object must be locked now");
1673 assert(obj->mark().has_monitor(), "must be");
1674 assert(!deoptee_thread->lock_stack().contains(obj()), "must be");
1675 assert(ObjectSynchronizer::read_monitor(thread, obj(), obj->mark())->has_owner(deoptee_thread), "must be");
1676 } else {
1677 ObjectSynchronizer::enter_for(obj, lock, deoptee_thread);
1678 assert(mon_info->owner()->is_locked(), "object must be locked now");
1679 }
1680 }
1681 }
1682 }
1683 return relocked_objects;
1684 }
1685 #endif // COMPILER2_OR_JVMCI
1686
1687 vframeArray* Deoptimization::create_vframeArray(JavaThread* thread, frame fr, RegisterMap *reg_map, GrowableArray<compiledVFrame*>* chunk, bool realloc_failures) {
1688 Events::log_deopt_message(thread, "DEOPT PACKING pc=" INTPTR_FORMAT " sp=" INTPTR_FORMAT, p2i(fr.pc()), p2i(fr.sp()));
1689
1690 // Register map for next frame (used for stack crawl). We capture
1691 // the state of the deopt'ing frame's caller. Thus if we need to
1692 // stuff a C2I adapter we can properly fill in the callee-save
1693 // register locations.
1694 frame caller = fr.sender(reg_map);
1695 int frame_size = pointer_delta_as_int(caller.sp(), fr.sp());
1696
1697 frame sender = caller;
1698
1699 // Since the Java thread being deoptimized will eventually adjust it's own stack,
1700 // the vframeArray containing the unpacking information is allocated in the C heap.
1701 // For Compiler1, the caller of the deoptimized frame is saved for use by unpack_frames().
1702 vframeArray* array = vframeArray::allocate(thread, frame_size, chunk, reg_map, sender, caller, fr, realloc_failures);
1703
1704 // Compare the vframeArray to the collected vframes
1705 assert(array->structural_compare(thread, chunk), "just checking");
1706
1707 if (TraceDeoptimization) {
1708 ResourceMark rm;
1709 stringStream st;
1710 st.print_cr("DEOPT PACKING thread=" INTPTR_FORMAT " vframeArray=" INTPTR_FORMAT, p2i(thread), p2i(array));
1711 st.print(" ");
1712 fr.print_on(&st);
1713 st.print_cr(" Virtual frames (innermost/newest first):");
1714 for (int index = 0; index < chunk->length(); index++) {
1715 compiledVFrame* vf = chunk->at(index);
1716 int bci = vf->raw_bci();
1717 const char* code_name;
1718 if (bci == SynchronizationEntryBCI) {
1719 code_name = "sync entry";
1720 } else {
1721 Bytecodes::Code code = vf->method()->code_at(bci);
1722 code_name = Bytecodes::name(code);
1723 }
1724
1725 st.print(" VFrame %d (" INTPTR_FORMAT ")", index, p2i(vf));
1726 st.print(" - %s", vf->method()->name_and_sig_as_C_string());
1727 st.print(" - %s", code_name);
1728 st.print_cr(" @ bci=%d ", bci);
1729 }
1730 tty->print_raw(st.freeze());
1731 tty->cr();
1732 }
1733
1734 return array;
1735 }
1736
1737 #if COMPILER2_OR_JVMCI
1738 void Deoptimization::pop_frames_failed_reallocs(JavaThread* thread, vframeArray* array) {
1739 // Reallocation of some scalar replaced objects failed. Record
1740 // that we need to pop all the interpreter frames for the
1741 // deoptimized compiled frame.
1742 assert(thread->frames_to_pop_failed_realloc() == 0, "missed frames to pop?");
1743 thread->set_frames_to_pop_failed_realloc(array->frames());
1744 // Unlock all monitors here otherwise the interpreter will see a
1745 // mix of locked and unlocked monitors (because of failed
1746 // reallocations of synchronized objects) and be confused.
1747 for (int i = 0; i < array->frames(); i++) {
1748 MonitorChunk* monitors = array->element(i)->monitors();
1749 if (monitors != nullptr) {
1750 // Unlock in reverse order starting from most nested monitor.
1751 for (int j = (monitors->number_of_monitors() - 1); j >= 0; j--) {
1752 BasicObjectLock* src = monitors->at(j);
1753 if (src->obj() != nullptr) {
1754 ObjectSynchronizer::exit(src->obj(), src->lock(), thread);
1755 }
1756 }
1757 array->element(i)->free_monitors();
1758 #ifdef ASSERT
1759 array->element(i)->set_removed_monitors();
1760 #endif
1761 }
1762 }
1763 }
1764 #endif
1765
1766 void Deoptimization::deoptimize_single_frame(JavaThread* thread, frame fr, Deoptimization::DeoptReason reason) {
1767 assert(fr.can_be_deoptimized(), "checking frame type");
1768
1769 nmethod* nm = fr.cb()->as_nmethod_or_null();
1770 assert(nm != nullptr, "only compiled methods can deopt");
1771 DeoptAction action = (nm->is_not_entrant() ? Action_make_not_entrant : Action_none);
1772 ScopeDesc* cur_sd = nm->scope_desc_at(fr.pc());
1773 Bytecodes::Code bc = (cur_sd->bci() == -1 ? Bytecodes::_nop // deopt on method entry
1774 : cur_sd->method()->java_code_at(cur_sd->bci()));
1775 gather_statistics(nm, reason, action, bc);
1776
1777 if (LogCompilation && xtty != nullptr) {
1778 ttyLocker ttyl;
1779 xtty->begin_head("deoptimized thread='" UINTX_FORMAT "' reason='%s' pc='" INTPTR_FORMAT "'",(uintx)thread->osthread()->thread_id(), trap_reason_name(reason), p2i(fr.pc()));
1780 nm->log_identity(xtty);
1781 xtty->end_head();
1782 for (ScopeDesc* sd = nm->scope_desc_at(fr.pc()); ; sd = sd->sender()) {
1783 xtty->begin_elem("jvms bci='%d'", sd->bci());
1784 xtty->method(sd->method());
1785 xtty->end_elem();
1786 if (sd->is_top()) break;
1787 }
1788 xtty->tail("deoptimized");
1789 }
1790
1791 Continuation::notify_deopt(thread, fr.sp());
1792
1793 // Patch the compiled method so that when execution returns to it we will
1794 // deopt the execution state and return to the interpreter.
1795 fr.deoptimize(thread);
1796 }
1797
1798 void Deoptimization::deoptimize(JavaThread* thread, frame fr, DeoptReason reason) {
1799 // Deoptimize only if the frame comes from compile code.
1800 // Do not deoptimize the frame which is already patched
1801 // during the execution of the loops below.
1802 if (!fr.is_compiled_frame() || fr.is_deoptimized_frame()) {
1803 return;
1804 }
1805 ResourceMark rm;
1806 deoptimize_single_frame(thread, fr, reason);
1807 }
1808
1809 #if INCLUDE_JVMCI
1810 address Deoptimization::deoptimize_for_missing_exception_handler(nmethod* nm) {
1811 // there is no exception handler for this pc => deoptimize
1812 nm->make_not_entrant();
1813
1814 // Use Deoptimization::deoptimize for all of its side-effects:
1815 // gathering traps statistics, logging...
1816 // it also patches the return pc but we do not care about that
1817 // since we return a continuation to the deopt_blob below.
1818 JavaThread* thread = JavaThread::current();
1819 RegisterMap reg_map(thread,
1820 RegisterMap::UpdateMap::skip,
1821 RegisterMap::ProcessFrames::include,
1822 RegisterMap::WalkContinuation::skip);
1823 frame runtime_frame = thread->last_frame();
1824 frame caller_frame = runtime_frame.sender(®_map);
1825 assert(caller_frame.cb()->as_nmethod_or_null() == nm, "expect top frame compiled method");
1826 vframe* vf = vframe::new_vframe(&caller_frame, ®_map, thread);
1827 compiledVFrame* cvf = compiledVFrame::cast(vf);
1828 ScopeDesc* imm_scope = cvf->scope();
1829 MethodData* imm_mdo = get_method_data(thread, methodHandle(thread, imm_scope->method()), true);
1830 if (imm_mdo != nullptr) {
1831 // Lock to read ProfileData, and ensure lock is not broken by a safepoint
1832 MutexLocker ml(imm_mdo->extra_data_lock(), Mutex::_no_safepoint_check_flag);
1833
1834 ProfileData* pdata = imm_mdo->allocate_bci_to_data(imm_scope->bci(), nullptr);
1835 if (pdata != nullptr && pdata->is_BitData()) {
1836 BitData* bit_data = (BitData*) pdata;
1837 bit_data->set_exception_seen();
1838 }
1839 }
1840
1841 Deoptimization::deoptimize(thread, caller_frame, Deoptimization::Reason_not_compiled_exception_handler);
1842
1843 MethodData* trap_mdo = get_method_data(thread, methodHandle(thread, nm->method()), true);
1844 if (trap_mdo != nullptr) {
1845 trap_mdo->inc_trap_count(Deoptimization::Reason_not_compiled_exception_handler);
1846 }
1847
1848 return SharedRuntime::deopt_blob()->unpack_with_exception_in_tls();
1849 }
1850 #endif
1851
1852 void Deoptimization::deoptimize_frame_internal(JavaThread* thread, intptr_t* id, DeoptReason reason) {
1853 assert(thread == Thread::current() ||
1854 thread->is_handshake_safe_for(Thread::current()) ||
1855 SafepointSynchronize::is_at_safepoint(),
1856 "can only deoptimize other thread at a safepoint/handshake");
1857 // Compute frame and register map based on thread and sp.
1858 RegisterMap reg_map(thread,
1859 RegisterMap::UpdateMap::skip,
1860 RegisterMap::ProcessFrames::include,
1861 RegisterMap::WalkContinuation::skip);
1862 frame fr = thread->last_frame();
1863 while (fr.id() != id) {
1864 fr = fr.sender(®_map);
1865 }
1866 deoptimize(thread, fr, reason);
1867 }
1868
1869
1870 void Deoptimization::deoptimize_frame(JavaThread* thread, intptr_t* id, DeoptReason reason) {
1871 Thread* current = Thread::current();
1872 if (thread == current || thread->is_handshake_safe_for(current)) {
1873 Deoptimization::deoptimize_frame_internal(thread, id, reason);
1874 } else {
1875 VM_DeoptimizeFrame deopt(thread, id, reason);
1876 VMThread::execute(&deopt);
1877 }
1878 }
1879
1880 void Deoptimization::deoptimize_frame(JavaThread* thread, intptr_t* id) {
1881 deoptimize_frame(thread, id, Reason_constraint);
1882 }
1883
1884 // JVMTI PopFrame support
1885 JRT_LEAF(void, Deoptimization::popframe_preserve_args(JavaThread* thread, int bytes_to_save, void* start_address))
1886 {
1887 assert(thread == JavaThread::current(), "pre-condition");
1888 thread->popframe_preserve_args(in_ByteSize(bytes_to_save), start_address);
1889 }
1890 JRT_END
1891
1892 MethodData*
1893 Deoptimization::get_method_data(JavaThread* thread, const methodHandle& m,
1894 bool create_if_missing) {
1895 JavaThread* THREAD = thread; // For exception macros.
1896 MethodData* mdo = m()->method_data();
1897 if (mdo == nullptr && create_if_missing && !HAS_PENDING_EXCEPTION) {
1898 // Build an MDO. Ignore errors like OutOfMemory;
1899 // that simply means we won't have an MDO to update.
1900 Method::build_profiling_method_data(m, THREAD);
1901 if (HAS_PENDING_EXCEPTION) {
1902 // Only metaspace OOM is expected. No Java code executed.
1903 assert((PENDING_EXCEPTION->is_a(vmClasses::OutOfMemoryError_klass())), "we expect only an OOM error here");
1904 CLEAR_PENDING_EXCEPTION;
1905 }
1906 mdo = m()->method_data();
1907 }
1908 return mdo;
1909 }
1910
1911 #if COMPILER2_OR_JVMCI
1912 void Deoptimization::load_class_by_index(const constantPoolHandle& constant_pool, int index, TRAPS) {
1913 // In case of an unresolved klass entry, load the class.
1914 // This path is exercised from case _ldc in Parse::do_one_bytecode,
1915 // and probably nowhere else.
1916 // Even that case would benefit from simply re-interpreting the
1917 // bytecode, without paying special attention to the class index.
1918 // So this whole "class index" feature should probably be removed.
1919
1920 if (constant_pool->tag_at(index).is_unresolved_klass()) {
1921 Klass* tk = constant_pool->klass_at(index, THREAD);
1922 if (HAS_PENDING_EXCEPTION) {
1923 // Exception happened during classloading. We ignore the exception here, since it
1924 // is going to be rethrown since the current activation is going to be deoptimized and
1925 // the interpreter will re-execute the bytecode.
1926 // Do not clear probable Async Exceptions.
1927 CLEAR_PENDING_NONASYNC_EXCEPTION;
1928 // Class loading called java code which may have caused a stack
1929 // overflow. If the exception was thrown right before the return
1930 // to the runtime the stack is no longer guarded. Reguard the
1931 // stack otherwise if we return to the uncommon trap blob and the
1932 // stack bang causes a stack overflow we crash.
1933 JavaThread* jt = THREAD;
1934 bool guard_pages_enabled = jt->stack_overflow_state()->reguard_stack_if_needed();
1935 assert(guard_pages_enabled, "stack banging in uncommon trap blob may cause crash");
1936 }
1937 return;
1938 }
1939
1940 assert(!constant_pool->tag_at(index).is_symbol(),
1941 "no symbolic names here, please");
1942 }
1943
1944 #if INCLUDE_JFR
1945
1946 class DeoptReasonSerializer : public JfrSerializer {
1947 public:
1948 void serialize(JfrCheckpointWriter& writer) {
1949 writer.write_count((u4)(Deoptimization::Reason_LIMIT + 1)); // + Reason::many (-1)
1950 for (int i = -1; i < Deoptimization::Reason_LIMIT; ++i) {
1951 writer.write_key((u8)i);
1952 writer.write(Deoptimization::trap_reason_name(i));
1953 }
1954 }
1955 };
1956
1957 class DeoptActionSerializer : public JfrSerializer {
1958 public:
1959 void serialize(JfrCheckpointWriter& writer) {
1960 static const u4 nof_actions = Deoptimization::Action_LIMIT;
1961 writer.write_count(nof_actions);
1962 for (u4 i = 0; i < Deoptimization::Action_LIMIT; ++i) {
1963 writer.write_key(i);
1964 writer.write(Deoptimization::trap_action_name((int)i));
1965 }
1966 }
1967 };
1968
1969 static void register_serializers() {
1970 static int critical_section = 0;
1971 if (1 == critical_section || Atomic::cmpxchg(&critical_section, 0, 1) == 1) {
1972 return;
1973 }
1974 JfrSerializer::register_serializer(TYPE_DEOPTIMIZATIONREASON, true, new DeoptReasonSerializer());
1975 JfrSerializer::register_serializer(TYPE_DEOPTIMIZATIONACTION, true, new DeoptActionSerializer());
1976 }
1977
1978 static void post_deoptimization_event(nmethod* nm,
1979 const Method* method,
1980 int trap_bci,
1981 int instruction,
1982 Deoptimization::DeoptReason reason,
1983 Deoptimization::DeoptAction action) {
1984 assert(nm != nullptr, "invariant");
1985 assert(method != nullptr, "invariant");
1986 if (EventDeoptimization::is_enabled()) {
1987 static bool serializers_registered = false;
1988 if (!serializers_registered) {
1989 register_serializers();
1990 serializers_registered = true;
1991 }
1992 EventDeoptimization event;
1993 event.set_compileId(nm->compile_id());
1994 event.set_compiler(nm->compiler_type());
1995 event.set_method(method);
1996 event.set_lineNumber(method->line_number_from_bci(trap_bci));
1997 event.set_bci(trap_bci);
1998 event.set_instruction(instruction);
1999 event.set_reason(reason);
2000 event.set_action(action);
2001 event.commit();
2002 }
2003 }
2004
2005 #endif // INCLUDE_JFR
2006
2007 static void log_deopt(nmethod* nm, Method* tm, intptr_t pc, frame& fr, int trap_bci,
2008 const char* reason_name, const char* reason_action) {
2009 LogTarget(Debug, deoptimization) lt;
2010 if (lt.is_enabled()) {
2011 LogStream ls(lt);
2012 bool is_osr = nm->is_osr_method();
2013 ls.print("cid=%4d %s level=%d",
2014 nm->compile_id(), (is_osr ? "osr" : " "), nm->comp_level());
2015 ls.print(" %s", tm->name_and_sig_as_C_string());
2016 ls.print(" trap_bci=%d ", trap_bci);
2017 if (is_osr) {
2018 ls.print("osr_bci=%d ", nm->osr_entry_bci());
2019 }
2020 ls.print("%s ", reason_name);
2021 ls.print("%s ", reason_action);
2022 ls.print_cr("pc=" INTPTR_FORMAT " relative_pc=" INTPTR_FORMAT,
2023 pc, fr.pc() - nm->code_begin());
2024 }
2025 }
2026
2027 JRT_ENTRY_PROF(void, Deoptimization, uncommon_trap_inner, Deoptimization::uncommon_trap_inner(JavaThread* current, jint trap_request)) {
2028 HandleMark hm(current);
2029
2030 // uncommon_trap() is called at the beginning of the uncommon trap
2031 // handler. Note this fact before we start generating temporary frames
2032 // that can confuse an asynchronous stack walker. This counter is
2033 // decremented at the end of unpack_frames().
2034
2035 current->inc_in_deopt_handler();
2036
2037 #if INCLUDE_JVMCI
2038 // JVMCI might need to get an exception from the stack, which in turn requires the register map to be valid
2039 RegisterMap reg_map(current,
2040 RegisterMap::UpdateMap::include,
2041 RegisterMap::ProcessFrames::include,
2042 RegisterMap::WalkContinuation::skip);
2043 #else
2044 RegisterMap reg_map(current,
2045 RegisterMap::UpdateMap::skip,
2046 RegisterMap::ProcessFrames::include,
2047 RegisterMap::WalkContinuation::skip);
2048 #endif
2049 frame stub_frame = current->last_frame();
2050 frame fr = stub_frame.sender(®_map);
2051
2052 // Log a message
2053 Events::log_deopt_message(current, "Uncommon trap: trap_request=" INT32_FORMAT_X_0 " fr.pc=" INTPTR_FORMAT " relative=" INTPTR_FORMAT,
2054 trap_request, p2i(fr.pc()), fr.pc() - fr.cb()->code_begin());
2055
2056 {
2057 ResourceMark rm;
2058
2059 DeoptReason reason = trap_request_reason(trap_request);
2060 DeoptAction action = trap_request_action(trap_request);
2061 #if INCLUDE_JVMCI
2062 int debug_id = trap_request_debug_id(trap_request);
2063 #endif
2064 jint unloaded_class_index = trap_request_index(trap_request); // CP idx or -1
2065
2066 vframe* vf = vframe::new_vframe(&fr, ®_map, current);
2067 compiledVFrame* cvf = compiledVFrame::cast(vf);
2068
2069 nmethod* nm = cvf->code();
2070
2071 ScopeDesc* trap_scope = cvf->scope();
2072
2073 bool is_receiver_constraint_failure = COMPILER2_PRESENT(VerifyReceiverTypes &&) (reason == Deoptimization::Reason_receiver_constraint);
2074
2075 if (is_receiver_constraint_failure) {
2076 tty->print_cr(" bci=%d pc=" INTPTR_FORMAT ", relative_pc=" INTPTR_FORMAT ", method=%s" JVMCI_ONLY(", debug_id=%d"),
2077 trap_scope->bci(), p2i(fr.pc()), fr.pc() - nm->code_begin(), trap_scope->method()->name_and_sig_as_C_string()
2078 JVMCI_ONLY(COMMA debug_id));
2079 }
2080
2081 methodHandle trap_method(current, trap_scope->method());
2082 int trap_bci = trap_scope->bci();
2083 #if INCLUDE_JVMCI
2084 jlong speculation = current->pending_failed_speculation();
2085 if (nm->is_compiled_by_jvmci()) {
2086 nm->update_speculation(current);
2087 } else {
2088 assert(speculation == 0, "There should not be a speculation for methods compiled by non-JVMCI compilers");
2089 }
2090
2091 if (trap_bci == SynchronizationEntryBCI) {
2092 trap_bci = 0;
2093 current->set_pending_monitorenter(true);
2094 }
2095
2096 if (reason == Deoptimization::Reason_transfer_to_interpreter) {
2097 current->set_pending_transfer_to_interpreter(true);
2098 }
2099 #endif
2100
2101 Bytecodes::Code trap_bc = trap_method->java_code_at(trap_bci);
2102 // Record this event in the histogram.
2103 gather_statistics(nm, reason, action, trap_bc);
2104
2105 // Ensure that we can record deopt. history:
2106 bool create_if_missing = ProfileTraps;
2107
2108 methodHandle profiled_method;
2109 #if INCLUDE_JVMCI
2110 if (nm->is_compiled_by_jvmci()) {
2111 profiled_method = methodHandle(current, nm->method());
2112 } else {
2113 profiled_method = trap_method;
2114 }
2115 #else
2116 profiled_method = trap_method;
2117 #endif
2118
2119 MethodData* trap_mdo =
2120 get_method_data(current, profiled_method, create_if_missing);
2121
2122 { // Log Deoptimization event for JFR, UL and event system
2123 Method* tm = trap_method();
2124 const char* reason_name = trap_reason_name(reason);
2125 const char* reason_action = trap_action_name(action);
2126 intptr_t pc = p2i(fr.pc());
2127
2128 JFR_ONLY(post_deoptimization_event(nm, tm, trap_bci, trap_bc, reason, action);)
2129 log_deopt(nm, tm, pc, fr, trap_bci, reason_name, reason_action);
2130 Events::log_deopt_message(current, "Uncommon trap: reason=%s action=%s pc=" INTPTR_FORMAT " method=%s @ %d %s",
2131 reason_name, reason_action, pc,
2132 tm->name_and_sig_as_C_string(), trap_bci, nm->compiler_name());
2133 }
2134
2135 // Print a bunch of diagnostics, if requested.
2136 if (TraceDeoptimization || LogCompilation || is_receiver_constraint_failure) {
2137 ResourceMark rm;
2138
2139 // Lock to read ProfileData, and ensure lock is not broken by a safepoint
2140 // We must do this already now, since we cannot acquire this lock while
2141 // holding the tty lock (lock ordering by rank).
2142 MutexLocker ml(trap_mdo->extra_data_lock(), Mutex::_no_safepoint_check_flag);
2143
2144 ttyLocker ttyl;
2145
2146 char buf[100];
2147 if (xtty != nullptr) {
2148 xtty->begin_head("uncommon_trap thread='" UINTX_FORMAT "' %s",
2149 os::current_thread_id(),
2150 format_trap_request(buf, sizeof(buf), trap_request));
2151 #if INCLUDE_JVMCI
2152 if (speculation != 0) {
2153 xtty->print(" speculation='" JLONG_FORMAT "'", speculation);
2154 }
2155 #endif
2156 nm->log_identity(xtty);
2157 }
2158 Symbol* class_name = nullptr;
2159 bool unresolved = false;
2160 if (unloaded_class_index >= 0) {
2161 constantPoolHandle constants (current, trap_method->constants());
2162 if (constants->tag_at(unloaded_class_index).is_unresolved_klass()) {
2163 class_name = constants->klass_name_at(unloaded_class_index);
2164 unresolved = true;
2165 if (xtty != nullptr)
2166 xtty->print(" unresolved='1'");
2167 } else if (constants->tag_at(unloaded_class_index).is_symbol()) {
2168 class_name = constants->symbol_at(unloaded_class_index);
2169 }
2170 if (xtty != nullptr)
2171 xtty->name(class_name);
2172 }
2173 if (xtty != nullptr && trap_mdo != nullptr && (int)reason < (int)MethodData::_trap_hist_limit) {
2174 // Dump the relevant MDO state.
2175 // This is the deopt count for the current reason, any previous
2176 // reasons or recompiles seen at this point.
2177 int dcnt = trap_mdo->trap_count(reason);
2178 if (dcnt != 0)
2179 xtty->print(" count='%d'", dcnt);
2180
2181 // We need to lock to read the ProfileData. But to keep the locks ordered, we need to
2182 // lock extra_data_lock before the tty lock.
2183 ProfileData* pdata = trap_mdo->bci_to_data(trap_bci);
2184 int dos = (pdata == nullptr)? 0: pdata->trap_state();
2185 if (dos != 0) {
2186 xtty->print(" state='%s'", format_trap_state(buf, sizeof(buf), dos));
2187 if (trap_state_is_recompiled(dos)) {
2188 int recnt2 = trap_mdo->overflow_recompile_count();
2189 if (recnt2 != 0)
2190 xtty->print(" recompiles2='%d'", recnt2);
2191 }
2192 }
2193 }
2194 if (xtty != nullptr) {
2195 xtty->stamp();
2196 xtty->end_head();
2197 }
2198 if (TraceDeoptimization) { // make noise on the tty
2199 stringStream st;
2200 st.print("UNCOMMON TRAP method=%s", trap_scope->method()->name_and_sig_as_C_string());
2201 st.print(" bci=%d pc=" INTPTR_FORMAT ", relative_pc=" INTPTR_FORMAT JVMCI_ONLY(", debug_id=%d"),
2202 trap_scope->bci(), p2i(fr.pc()), fr.pc() - nm->code_begin() JVMCI_ONLY(COMMA debug_id));
2203 st.print(" compiler=%s compile_id=%d", nm->compiler_name(), nm->compile_id());
2204 #if INCLUDE_JVMCI
2205 if (nm->is_compiled_by_jvmci()) {
2206 const char* installed_code_name = nm->jvmci_name();
2207 if (installed_code_name != nullptr) {
2208 st.print(" (JVMCI: installed code name=%s) ", installed_code_name);
2209 }
2210 }
2211 #endif
2212 st.print(" (@" INTPTR_FORMAT ") thread=" UINTX_FORMAT " reason=%s action=%s unloaded_class_index=%d" JVMCI_ONLY(" debug_id=%d"),
2213 p2i(fr.pc()),
2214 os::current_thread_id(),
2215 trap_reason_name(reason),
2216 trap_action_name(action),
2217 unloaded_class_index
2218 #if INCLUDE_JVMCI
2219 , debug_id
2220 #endif
2221 );
2222 if (class_name != nullptr) {
2223 st.print(unresolved ? " unresolved class: " : " symbol: ");
2224 class_name->print_symbol_on(&st);
2225 }
2226 st.cr();
2227 tty->print_raw(st.freeze());
2228 }
2229 if (xtty != nullptr) {
2230 // Log the precise location of the trap.
2231 for (ScopeDesc* sd = trap_scope; ; sd = sd->sender()) {
2232 xtty->begin_elem("jvms bci='%d'", sd->bci());
2233 xtty->method(sd->method());
2234 xtty->end_elem();
2235 if (sd->is_top()) break;
2236 }
2237 xtty->tail("uncommon_trap");
2238 }
2239 }
2240 // (End diagnostic printout.)
2241
2242 if (is_receiver_constraint_failure) {
2243 fatal("missing receiver type check");
2244 }
2245
2246 // Load class if necessary
2247 if (unloaded_class_index >= 0) {
2248 constantPoolHandle constants(current, trap_method->constants());
2249 load_class_by_index(constants, unloaded_class_index, THREAD);
2250 }
2251
2252 // Flush the nmethod if necessary and desirable.
2253 //
2254 // We need to avoid situations where we are re-flushing the nmethod
2255 // because of a hot deoptimization site. Repeated flushes at the same
2256 // point need to be detected by the compiler and avoided. If the compiler
2257 // cannot avoid them (or has a bug and "refuses" to avoid them), this
2258 // module must take measures to avoid an infinite cycle of recompilation
2259 // and deoptimization. There are several such measures:
2260 //
2261 // 1. If a recompilation is ordered a second time at some site X
2262 // and for the same reason R, the action is adjusted to 'reinterpret',
2263 // to give the interpreter time to exercise the method more thoroughly.
2264 // If this happens, the method's overflow_recompile_count is incremented.
2265 //
2266 // 2. If the compiler fails to reduce the deoptimization rate, then
2267 // the method's overflow_recompile_count will begin to exceed the set
2268 // limit PerBytecodeRecompilationCutoff. If this happens, the action
2269 // is adjusted to 'make_not_compilable', and the method is abandoned
2270 // to the interpreter. This is a performance hit for hot methods,
2271 // but is better than a disastrous infinite cycle of recompilations.
2272 // (Actually, only the method containing the site X is abandoned.)
2273 //
2274 // 3. In parallel with the previous measures, if the total number of
2275 // recompilations of a method exceeds the much larger set limit
2276 // PerMethodRecompilationCutoff, the method is abandoned.
2277 // This should only happen if the method is very large and has
2278 // many "lukewarm" deoptimizations. The code which enforces this
2279 // limit is elsewhere (class nmethod, class Method).
2280 //
2281 // Note that the per-BCI 'is_recompiled' bit gives the compiler one chance
2282 // to recompile at each bytecode independently of the per-BCI cutoff.
2283 //
2284 // The decision to update code is up to the compiler, and is encoded
2285 // in the Action_xxx code. If the compiler requests Action_none
2286 // no trap state is changed, no compiled code is changed, and the
2287 // computation suffers along in the interpreter.
2288 //
2289 // The other action codes specify various tactics for decompilation
2290 // and recompilation. Action_maybe_recompile is the loosest, and
2291 // allows the compiled code to stay around until enough traps are seen,
2292 // and until the compiler gets around to recompiling the trapping method.
2293 //
2294 // The other actions cause immediate removal of the present code.
2295
2296 // Traps caused by injected profile shouldn't pollute trap counts.
2297 bool injected_profile_trap = trap_method->has_injected_profile() &&
2298 (reason == Reason_intrinsic || reason == Reason_unreached);
2299
2300 bool update_trap_state = (reason != Reason_tenured) && !injected_profile_trap;
2301 bool make_not_entrant = false;
2302 bool make_not_compilable = false;
2303 bool reprofile = false;
2304 switch (action) {
2305 case Action_none:
2306 // Keep the old code.
2307 update_trap_state = false;
2308 break;
2309 case Action_maybe_recompile:
2310 // Do not need to invalidate the present code, but we can
2311 // initiate another
2312 // Start compiler without (necessarily) invalidating the nmethod.
2313 // The system will tolerate the old code, but new code should be
2314 // generated when possible.
2315 break;
2316 case Action_reinterpret:
2317 // Go back into the interpreter for a while, and then consider
2318 // recompiling form scratch.
2319 make_not_entrant = true;
2320 // Reset invocation counter for outer most method.
2321 // This will allow the interpreter to exercise the bytecodes
2322 // for a while before recompiling.
2323 // By contrast, Action_make_not_entrant is immediate.
2324 //
2325 // Note that the compiler will track null_check, null_assert,
2326 // range_check, and class_check events and log them as if they
2327 // had been traps taken from compiled code. This will update
2328 // the MDO trap history so that the next compilation will
2329 // properly detect hot trap sites.
2330 reprofile = true;
2331 break;
2332 case Action_make_not_entrant:
2333 // Request immediate recompilation, and get rid of the old code.
2334 // Make them not entrant, so next time they are called they get
2335 // recompiled. Unloaded classes are loaded now so recompile before next
2336 // time they are called. Same for uninitialized. The interpreter will
2337 // link the missing class, if any.
2338 make_not_entrant = true;
2339 break;
2340 case Action_make_not_compilable:
2341 // Give up on compiling this method at all.
2342 make_not_entrant = true;
2343 make_not_compilable = true;
2344 break;
2345 default:
2346 ShouldNotReachHere();
2347 }
2348
2349 // Setting +ProfileTraps fixes the following, on all platforms:
2350 // 4852688: ProfileInterpreter is off by default for ia64. The result is
2351 // infinite heroic-opt-uncommon-trap/deopt/recompile cycles, since the
2352 // recompile relies on a MethodData* to record heroic opt failures.
2353
2354 // Whether the interpreter is producing MDO data or not, we also need
2355 // to use the MDO to detect hot deoptimization points and control
2356 // aggressive optimization.
2357 bool inc_recompile_count = false;
2358
2359 // Lock to read ProfileData, and ensure lock is not broken by a safepoint
2360 ConditionalMutexLocker ml((trap_mdo != nullptr) ? trap_mdo->extra_data_lock() : nullptr,
2361 (trap_mdo != nullptr),
2362 Mutex::_no_safepoint_check_flag);
2363 ProfileData* pdata = nullptr;
2364 if (ProfileTraps && CompilerConfig::is_c2_or_jvmci_compiler_enabled() && update_trap_state && trap_mdo != nullptr) {
2365 assert(trap_mdo == get_method_data(current, profiled_method, false), "sanity");
2366 uint this_trap_count = 0;
2367 bool maybe_prior_trap = false;
2368 bool maybe_prior_recompile = false;
2369
2370 pdata = query_update_method_data(trap_mdo, trap_bci, reason, true,
2371 #if INCLUDE_JVMCI
2372 nm->is_compiled_by_jvmci() && nm->is_osr_method(),
2373 #endif
2374 nm->method(),
2375 //outputs:
2376 this_trap_count,
2377 maybe_prior_trap,
2378 maybe_prior_recompile);
2379 // Because the interpreter also counts null, div0, range, and class
2380 // checks, these traps from compiled code are double-counted.
2381 // This is harmless; it just means that the PerXTrapLimit values
2382 // are in effect a little smaller than they look.
2383
2384 DeoptReason per_bc_reason = reason_recorded_per_bytecode_if_any(reason);
2385 if (per_bc_reason != Reason_none) {
2386 // Now take action based on the partially known per-BCI history.
2387 if (maybe_prior_trap
2388 && this_trap_count >= (uint)PerBytecodeTrapLimit) {
2389 // If there are too many traps at this BCI, force a recompile.
2390 // This will allow the compiler to see the limit overflow, and
2391 // take corrective action, if possible. The compiler generally
2392 // does not use the exact PerBytecodeTrapLimit value, but instead
2393 // changes its tactics if it sees any traps at all. This provides
2394 // a little hysteresis, delaying a recompile until a trap happens
2395 // several times.
2396 //
2397 // Actually, since there is only one bit of counter per BCI,
2398 // the possible per-BCI counts are {0,1,(per-method count)}.
2399 // This produces accurate results if in fact there is only
2400 // one hot trap site, but begins to get fuzzy if there are
2401 // many sites. For example, if there are ten sites each
2402 // trapping two or more times, they each get the blame for
2403 // all of their traps.
2404 make_not_entrant = true;
2405 }
2406
2407 // Detect repeated recompilation at the same BCI, and enforce a limit.
2408 if (make_not_entrant && maybe_prior_recompile) {
2409 // More than one recompile at this point.
2410 inc_recompile_count = maybe_prior_trap;
2411 }
2412 } else {
2413 // For reasons which are not recorded per-bytecode, we simply
2414 // force recompiles unconditionally.
2415 // (Note that PerMethodRecompilationCutoff is enforced elsewhere.)
2416 make_not_entrant = true;
2417 }
2418
2419 // Go back to the compiler if there are too many traps in this method.
2420 if (this_trap_count >= per_method_trap_limit(reason)) {
2421 // If there are too many traps in this method, force a recompile.
2422 // This will allow the compiler to see the limit overflow, and
2423 // take corrective action, if possible.
2424 // (This condition is an unlikely backstop only, because the
2425 // PerBytecodeTrapLimit is more likely to take effect first,
2426 // if it is applicable.)
2427 make_not_entrant = true;
2428 }
2429
2430 // Here's more hysteresis: If there has been a recompile at
2431 // this trap point already, run the method in the interpreter
2432 // for a while to exercise it more thoroughly.
2433 if (make_not_entrant && maybe_prior_recompile && maybe_prior_trap) {
2434 reprofile = true;
2435 }
2436 }
2437
2438 // Take requested actions on the method:
2439
2440 // Recompile
2441 if (make_not_entrant) {
2442 if (!nm->make_not_entrant()) {
2443 return; // the call did not change nmethod's state
2444 }
2445
2446 if (pdata != nullptr) {
2447 // Record the recompilation event, if any.
2448 int tstate0 = pdata->trap_state();
2449 int tstate1 = trap_state_set_recompiled(tstate0, true);
2450 if (tstate1 != tstate0)
2451 pdata->set_trap_state(tstate1);
2452 }
2453
2454 // For code aging we count traps separately here, using make_not_entrant()
2455 // as a guard against simultaneous deopts in multiple threads.
2456 if (reason == Reason_tenured && trap_mdo != nullptr) {
2457 trap_mdo->inc_tenure_traps();
2458 }
2459 }
2460
2461 if (inc_recompile_count) {
2462 trap_mdo->inc_overflow_recompile_count();
2463 if ((uint)trap_mdo->overflow_recompile_count() >
2464 (uint)PerBytecodeRecompilationCutoff) {
2465 // Give up on the method containing the bad BCI.
2466 if (trap_method() == nm->method()) {
2467 make_not_compilable = true;
2468 } else {
2469 trap_method->set_not_compilable("overflow_recompile_count > PerBytecodeRecompilationCutoff", CompLevel_full_optimization);
2470 // But give grace to the enclosing nm->method().
2471 }
2472 }
2473 }
2474
2475 // Reprofile
2476 if (reprofile) {
2477 CompilationPolicy::reprofile(trap_scope, nm->is_osr_method());
2478 }
2479
2480 // Give up compiling
2481 if (make_not_compilable && !nm->method()->is_not_compilable(CompLevel_full_optimization)) {
2482 assert(make_not_entrant, "consistent");
2483 nm->method()->set_not_compilable("give up compiling", CompLevel_full_optimization);
2484 }
2485
2486 if (ProfileExceptionHandlers && trap_mdo != nullptr) {
2487 BitData* exception_handler_data = trap_mdo->exception_handler_bci_to_data_or_null(trap_bci);
2488 if (exception_handler_data != nullptr) {
2489 // uncommon trap at the start of an exception handler.
2490 // C2 generates these for un-entered exception handlers.
2491 // mark the handler as entered to avoid generating
2492 // another uncommon trap the next time the handler is compiled
2493 exception_handler_data->set_exception_handler_entered();
2494 }
2495 }
2496
2497 } // Free marked resources
2498
2499 }
2500 JRT_END
2501
2502 ProfileData*
2503 Deoptimization::query_update_method_data(MethodData* trap_mdo,
2504 int trap_bci,
2505 Deoptimization::DeoptReason reason,
2506 bool update_total_trap_count,
2507 #if INCLUDE_JVMCI
2508 bool is_osr,
2509 #endif
2510 Method* compiled_method,
2511 //outputs:
2512 uint& ret_this_trap_count,
2513 bool& ret_maybe_prior_trap,
2514 bool& ret_maybe_prior_recompile) {
2515 trap_mdo->check_extra_data_locked();
2516
2517 bool maybe_prior_trap = false;
2518 bool maybe_prior_recompile = false;
2519 uint this_trap_count = 0;
2520 if (update_total_trap_count) {
2521 uint idx = reason;
2522 #if INCLUDE_JVMCI
2523 if (is_osr) {
2524 // Upper half of history array used for traps in OSR compilations
2525 idx += Reason_TRAP_HISTORY_LENGTH;
2526 }
2527 #endif
2528 uint prior_trap_count = trap_mdo->trap_count(idx);
2529 this_trap_count = trap_mdo->inc_trap_count(idx);
2530
2531 // If the runtime cannot find a place to store trap history,
2532 // it is estimated based on the general condition of the method.
2533 // If the method has ever been recompiled, or has ever incurred
2534 // a trap with the present reason , then this BCI is assumed
2535 // (pessimistically) to be the culprit.
2536 maybe_prior_trap = (prior_trap_count != 0);
2537 maybe_prior_recompile = (trap_mdo->decompile_count() != 0);
2538 }
2539 ProfileData* pdata = nullptr;
2540
2541
2542 // For reasons which are recorded per bytecode, we check per-BCI data.
2543 DeoptReason per_bc_reason = reason_recorded_per_bytecode_if_any(reason);
2544 assert(per_bc_reason != Reason_none || update_total_trap_count, "must be");
2545 if (per_bc_reason != Reason_none) {
2546 // Find the profile data for this BCI. If there isn't one,
2547 // try to allocate one from the MDO's set of spares.
2548 // This will let us detect a repeated trap at this point.
2549 pdata = trap_mdo->allocate_bci_to_data(trap_bci, reason_is_speculate(reason) ? compiled_method : nullptr);
2550
2551 if (pdata != nullptr) {
2552 if (reason_is_speculate(reason) && !pdata->is_SpeculativeTrapData()) {
2553 if (LogCompilation && xtty != nullptr) {
2554 ttyLocker ttyl;
2555 // no more room for speculative traps in this MDO
2556 xtty->elem("speculative_traps_oom");
2557 }
2558 }
2559 // Query the trap state of this profile datum.
2560 int tstate0 = pdata->trap_state();
2561 if (!trap_state_has_reason(tstate0, per_bc_reason))
2562 maybe_prior_trap = false;
2563 if (!trap_state_is_recompiled(tstate0))
2564 maybe_prior_recompile = false;
2565
2566 // Update the trap state of this profile datum.
2567 int tstate1 = tstate0;
2568 // Record the reason.
2569 tstate1 = trap_state_add_reason(tstate1, per_bc_reason);
2570 // Store the updated state on the MDO, for next time.
2571 if (tstate1 != tstate0)
2572 pdata->set_trap_state(tstate1);
2573 } else {
2574 if (LogCompilation && xtty != nullptr) {
2575 ttyLocker ttyl;
2576 // Missing MDP? Leave a small complaint in the log.
2577 xtty->elem("missing_mdp bci='%d'", trap_bci);
2578 }
2579 }
2580 }
2581
2582 // Return results:
2583 ret_this_trap_count = this_trap_count;
2584 ret_maybe_prior_trap = maybe_prior_trap;
2585 ret_maybe_prior_recompile = maybe_prior_recompile;
2586 return pdata;
2587 }
2588
2589 void
2590 Deoptimization::update_method_data_from_interpreter(MethodData* trap_mdo, int trap_bci, int reason) {
2591 ResourceMark rm;
2592 // Ignored outputs:
2593 uint ignore_this_trap_count;
2594 bool ignore_maybe_prior_trap;
2595 bool ignore_maybe_prior_recompile;
2596 assert(!reason_is_speculate(reason), "reason speculate only used by compiler");
2597 // JVMCI uses the total counts to determine if deoptimizations are happening too frequently -> do not adjust total counts
2598 bool update_total_counts = true JVMCI_ONLY( && !UseJVMCICompiler);
2599
2600 // Lock to read ProfileData, and ensure lock is not broken by a safepoint
2601 MutexLocker ml(trap_mdo->extra_data_lock(), Mutex::_no_safepoint_check_flag);
2602
2603 query_update_method_data(trap_mdo, trap_bci,
2604 (DeoptReason)reason,
2605 update_total_counts,
2606 #if INCLUDE_JVMCI
2607 false,
2608 #endif
2609 nullptr,
2610 ignore_this_trap_count,
2611 ignore_maybe_prior_trap,
2612 ignore_maybe_prior_recompile);
2613 }
2614
2615 PROF_ENTRY(Deoptimization::UnrollBlock*, Deoptimization, uncommon_trap, Deoptimization::uncommon_trap(JavaThread* current, jint trap_request, jint exec_mode))
2616 // Enable WXWrite: current function is called from methods compiled by C2 directly
2617 MACOS_AARCH64_ONLY(ThreadWXEnable wx(WXWrite, current));
2618
2619 // Still in Java no safepoints
2620 {
2621 // This enters VM and may safepoint
2622 uncommon_trap_inner(current, trap_request);
2623 }
2624 HandleMark hm(current);
2625 return fetch_unroll_info_helper(current, exec_mode);
2626 PROF_END
2627
2628 // Local derived constants.
2629 // Further breakdown of DataLayout::trap_state, as promised by DataLayout.
2630 const int DS_REASON_MASK = ((uint)DataLayout::trap_mask) >> 1;
2631 const int DS_RECOMPILE_BIT = DataLayout::trap_mask - DS_REASON_MASK;
2632
2633 //---------------------------trap_state_reason---------------------------------
2634 Deoptimization::DeoptReason
2635 Deoptimization::trap_state_reason(int trap_state) {
2636 // This assert provides the link between the width of DataLayout::trap_bits
2637 // and the encoding of "recorded" reasons. It ensures there are enough
2638 // bits to store all needed reasons in the per-BCI MDO profile.
2639 assert(DS_REASON_MASK >= Reason_RECORDED_LIMIT, "enough bits");
2640 int recompile_bit = (trap_state & DS_RECOMPILE_BIT);
2641 trap_state -= recompile_bit;
2642 if (trap_state == DS_REASON_MASK) {
2643 return Reason_many;
2644 } else {
2645 assert((int)Reason_none == 0, "state=0 => Reason_none");
2646 return (DeoptReason)trap_state;
2647 }
2648 }
2649 //-------------------------trap_state_has_reason-------------------------------
2650 int Deoptimization::trap_state_has_reason(int trap_state, int reason) {
2651 assert(reason_is_recorded_per_bytecode((DeoptReason)reason), "valid reason");
2652 assert(DS_REASON_MASK >= Reason_RECORDED_LIMIT, "enough bits");
2653 int recompile_bit = (trap_state & DS_RECOMPILE_BIT);
2654 trap_state -= recompile_bit;
2655 if (trap_state == DS_REASON_MASK) {
2656 return -1; // true, unspecifically (bottom of state lattice)
2657 } else if (trap_state == reason) {
2658 return 1; // true, definitely
2659 } else if (trap_state == 0) {
2660 return 0; // false, definitely (top of state lattice)
2661 } else {
2662 return 0; // false, definitely
2663 }
2664 }
2665 //-------------------------trap_state_add_reason-------------------------------
2666 int Deoptimization::trap_state_add_reason(int trap_state, int reason) {
2667 assert(reason_is_recorded_per_bytecode((DeoptReason)reason) || reason == Reason_many, "valid reason");
2668 int recompile_bit = (trap_state & DS_RECOMPILE_BIT);
2669 trap_state -= recompile_bit;
2670 if (trap_state == DS_REASON_MASK) {
2671 return trap_state + recompile_bit; // already at state lattice bottom
2672 } else if (trap_state == reason) {
2673 return trap_state + recompile_bit; // the condition is already true
2674 } else if (trap_state == 0) {
2675 return reason + recompile_bit; // no condition has yet been true
2676 } else {
2677 return DS_REASON_MASK + recompile_bit; // fall to state lattice bottom
2678 }
2679 }
2680 //-----------------------trap_state_is_recompiled------------------------------
2681 bool Deoptimization::trap_state_is_recompiled(int trap_state) {
2682 return (trap_state & DS_RECOMPILE_BIT) != 0;
2683 }
2684 //-----------------------trap_state_set_recompiled-----------------------------
2685 int Deoptimization::trap_state_set_recompiled(int trap_state, bool z) {
2686 if (z) return trap_state | DS_RECOMPILE_BIT;
2687 else return trap_state & ~DS_RECOMPILE_BIT;
2688 }
2689 //---------------------------format_trap_state---------------------------------
2690 // This is used for debugging and diagnostics, including LogFile output.
2691 const char* Deoptimization::format_trap_state(char* buf, size_t buflen,
2692 int trap_state) {
2693 assert(buflen > 0, "sanity");
2694 DeoptReason reason = trap_state_reason(trap_state);
2695 bool recomp_flag = trap_state_is_recompiled(trap_state);
2696 // Re-encode the state from its decoded components.
2697 int decoded_state = 0;
2698 if (reason_is_recorded_per_bytecode(reason) || reason == Reason_many)
2699 decoded_state = trap_state_add_reason(decoded_state, reason);
2700 if (recomp_flag)
2701 decoded_state = trap_state_set_recompiled(decoded_state, recomp_flag);
2702 // If the state re-encodes properly, format it symbolically.
2703 // Because this routine is used for debugging and diagnostics,
2704 // be robust even if the state is a strange value.
2705 size_t len;
2706 if (decoded_state != trap_state) {
2707 // Random buggy state that doesn't decode??
2708 len = jio_snprintf(buf, buflen, "#%d", trap_state);
2709 } else {
2710 len = jio_snprintf(buf, buflen, "%s%s",
2711 trap_reason_name(reason),
2712 recomp_flag ? " recompiled" : "");
2713 }
2714 return buf;
2715 }
2716
2717
2718 //--------------------------------statics--------------------------------------
2719 const char* Deoptimization::_trap_reason_name[] = {
2720 // Note: Keep this in sync. with enum DeoptReason.
2721 "none",
2722 "null_check",
2723 "null_assert" JVMCI_ONLY("_or_unreached0"),
2724 "range_check",
2725 "class_check",
2726 "array_check",
2727 "intrinsic" JVMCI_ONLY("_or_type_checked_inlining"),
2728 "bimorphic" JVMCI_ONLY("_or_optimized_type_check"),
2729 "profile_predicate",
2730 "unloaded",
2731 "uninitialized",
2732 "initialized",
2733 "unreached",
2734 "unhandled",
2735 "constraint",
2736 "div0_check",
2737 "age",
2738 "predicate",
2739 "loop_limit_check",
2740 "speculate_class_check",
2741 "speculate_null_check",
2742 "speculate_null_assert",
2743 "unstable_if",
2744 "unstable_fused_if",
2745 "receiver_constraint",
2746 #if INCLUDE_JVMCI
2747 "aliasing",
2748 "transfer_to_interpreter",
2749 "not_compiled_exception_handler",
2750 "unresolved",
2751 "jsr_mismatch",
2752 #endif
2753 "tenured"
2754 };
2755 const char* Deoptimization::_trap_action_name[] = {
2756 // Note: Keep this in sync. with enum DeoptAction.
2757 "none",
2758 "maybe_recompile",
2759 "reinterpret",
2760 "make_not_entrant",
2761 "make_not_compilable"
2762 };
2763
2764 const char* Deoptimization::trap_reason_name(int reason) {
2765 // Check that every reason has a name
2766 STATIC_ASSERT(sizeof(_trap_reason_name)/sizeof(const char*) == Reason_LIMIT);
2767
2768 if (reason == Reason_many) return "many";
2769 if ((uint)reason < Reason_LIMIT)
2770 return _trap_reason_name[reason];
2771 static char buf[20];
2772 os::snprintf_checked(buf, sizeof(buf), "reason%d", reason);
2773 return buf;
2774 }
2775 const char* Deoptimization::trap_action_name(int action) {
2776 // Check that every action has a name
2777 STATIC_ASSERT(sizeof(_trap_action_name)/sizeof(const char*) == Action_LIMIT);
2778
2779 if ((uint)action < Action_LIMIT)
2780 return _trap_action_name[action];
2781 static char buf[20];
2782 os::snprintf_checked(buf, sizeof(buf), "action%d", action);
2783 return buf;
2784 }
2785
2786 // This is used for debugging and diagnostics, including LogFile output.
2787 const char* Deoptimization::format_trap_request(char* buf, size_t buflen,
2788 int trap_request) {
2789 jint unloaded_class_index = trap_request_index(trap_request);
2790 const char* reason = trap_reason_name(trap_request_reason(trap_request));
2791 const char* action = trap_action_name(trap_request_action(trap_request));
2792 #if INCLUDE_JVMCI
2793 int debug_id = trap_request_debug_id(trap_request);
2794 #endif
2795 size_t len;
2796 if (unloaded_class_index < 0) {
2797 len = jio_snprintf(buf, buflen, "reason='%s' action='%s'" JVMCI_ONLY(" debug_id='%d'"),
2798 reason, action
2799 #if INCLUDE_JVMCI
2800 ,debug_id
2801 #endif
2802 );
2803 } else {
2804 len = jio_snprintf(buf, buflen, "reason='%s' action='%s' index='%d'" JVMCI_ONLY(" debug_id='%d'"),
2805 reason, action, unloaded_class_index
2806 #if INCLUDE_JVMCI
2807 ,debug_id
2808 #endif
2809 );
2810 }
2811 return buf;
2812 }
2813
2814 juint Deoptimization::_deoptimization_hist
2815 [1 + 4 + 5] // total + online + archived
2816 [Deoptimization::Reason_LIMIT]
2817 [1 + Deoptimization::Action_LIMIT]
2818 [Deoptimization::BC_CASE_LIMIT]
2819 = {0};
2820
2821 enum {
2822 LSB_BITS = 8,
2823 LSB_MASK = right_n_bits(LSB_BITS)
2824 };
2825
2826 static void update(juint* cases, Bytecodes::Code bc) {
2827 juint* bc_counter_addr = nullptr;
2828 juint bc_counter = 0;
2829 // Look for an unused counter, or an exact match to this BC.
2830 if (bc != Bytecodes::_illegal) {
2831 for (int bc_case = 0; bc_case < Deoptimization::BC_CASE_LIMIT; bc_case++) {
2832 juint* counter_addr = &cases[bc_case];
2833 juint counter = *counter_addr;
2834 if ((counter == 0 && bc_counter_addr == nullptr)
2835 || (Bytecodes::Code)(counter & LSB_MASK) == bc) {
2836 // this counter is either free or is already devoted to this BC
2837 bc_counter_addr = counter_addr;
2838 bc_counter = counter | bc;
2839 }
2840 }
2841 }
2842 if (bc_counter_addr == nullptr) {
2843 // Overflow, or no given bytecode.
2844 bc_counter_addr = &cases[Deoptimization::BC_CASE_LIMIT-1];
2845 bc_counter = (*bc_counter_addr & ~LSB_MASK); // clear LSB
2846 }
2847 *bc_counter_addr = bc_counter + (1 << LSB_BITS);
2848 }
2849
2850
2851 void Deoptimization::gather_statistics(nmethod* nm, DeoptReason reason, DeoptAction action,
2852 Bytecodes::Code bc) {
2853 assert(reason >= 0 && reason < Reason_LIMIT, "oob");
2854 assert(action >= 0 && action < Action_LIMIT, "oob");
2855 _deoptimization_hist[0][Reason_none][0][0] += 1; // total
2856 _deoptimization_hist[0][reason][0][0] += 1; // per-reason total
2857
2858 update(_deoptimization_hist[0][reason][1+action], bc);
2859
2860 uint lvl = nm->comp_level() + (nm->is_scc() ? 4 : 0) + (nm->preloaded() ? 1 : 0);
2861 _deoptimization_hist[lvl][Reason_none][0][0] += 1; // total
2862 _deoptimization_hist[lvl][reason][0][0] += 1; // per-reason total
2863 update(_deoptimization_hist[lvl][reason][1+action], bc);
2864 }
2865
2866 jint Deoptimization::total_deoptimization_count() {
2867 return _deoptimization_hist[0][Reason_none][0][0];
2868 }
2869
2870 // Get the deopt count for a specific reason and a specific action. If either
2871 // one of 'reason' or 'action' is null, the method returns the sum of all
2872 // deoptimizations with the specific 'action' or 'reason' respectively.
2873 // If both arguments are null, the method returns the total deopt count.
2874 jint Deoptimization::deoptimization_count(const char *reason_str, const char *action_str) {
2875 if (reason_str == nullptr && action_str == nullptr) {
2876 return total_deoptimization_count();
2877 }
2878 juint counter = 0;
2879 for (int reason = 0; reason < Reason_LIMIT; reason++) {
2880 if (reason_str == nullptr || !strcmp(reason_str, trap_reason_name(reason))) {
2881 for (int action = 0; action < Action_LIMIT; action++) {
2882 if (action_str == nullptr || !strcmp(action_str, trap_action_name(action))) {
2883 juint* cases = _deoptimization_hist[0][reason][1+action];
2884 for (int bc_case = 0; bc_case < BC_CASE_LIMIT; bc_case++) {
2885 counter += cases[bc_case] >> LSB_BITS;
2886 }
2887 }
2888 }
2889 }
2890 }
2891 return counter;
2892 }
2893
2894 void Deoptimization::print_statistics() {
2895 ttyLocker ttyl;
2896 if (xtty != nullptr) xtty->head("statistics type='deoptimization'");
2897 tty->print_cr("Deoptimization traps recorded:");
2898 print_statistics_on(tty);
2899 if (xtty != nullptr) xtty->tail("statistics");
2900 }
2901
2902 void Deoptimization::print_statistics_on(const char* title, int lvl, outputStream* st) {
2903 juint total = _deoptimization_hist[lvl][Reason_none][0][0];
2904 juint account = total;
2905 #define PRINT_STAT_LINE(name, r) \
2906 st->print_cr(" %d (%4.1f%%) %s", (int)(r), ((r) == total ? 100.0 : (((r) * 100.0) / total)), name);
2907 if (total > 0) {
2908 st->print(" %s: ", title);
2909 PRINT_STAT_LINE("total", total);
2910 // For each non-zero entry in the histogram, print the reason,
2911 // the action, and (if specifically known) the type of bytecode.
2912 for (int reason = 0; reason < Reason_LIMIT; reason++) {
2913 for (int action = 0; action < Action_LIMIT; action++) {
2914 juint* cases = Deoptimization::_deoptimization_hist[lvl][reason][1+action];
2915 for (int bc_case = 0; bc_case < BC_CASE_LIMIT; bc_case++) {
2916 juint counter = cases[bc_case];
2917 if (counter != 0) {
2918 Bytecodes::Code bc = (Bytecodes::Code)(counter & LSB_MASK);
2919 const char* bc_name = "other";
2920 if (bc_case == (BC_CASE_LIMIT-1) && bc == Bytecodes::_nop) {
2921 // overwritten
2922 } else if (Bytecodes::is_defined(bc)) {
2923 bc_name = Bytecodes::name(bc);
2924 }
2925 juint r = counter >> LSB_BITS;
2926 st->print_cr(" %-34s %16s %16s: " UINT32_FORMAT_W(5) " (%4.1f%%)",
2927 trap_reason_name(reason), trap_action_name(action), bc_name,
2928 r, (r * 100.0) / total);
2929 account -= r;
2930 }
2931 }
2932 }
2933 }
2934 if (account != 0) {
2935 PRINT_STAT_LINE("unaccounted", account);
2936 }
2937 #undef PRINT_STAT_LINE
2938 }
2939 }
2940
2941 void Deoptimization::print_statistics_on(outputStream* st) {
2942 // print_statistics_on("Total", 0, st);
2943 print_statistics_on("Tier1", 1, st);
2944 print_statistics_on("Tier2", 2, st);
2945 print_statistics_on("Tier3", 3, st);
2946 print_statistics_on("Tier4", 4, st);
2947
2948 print_statistics_on("SC Tier1", 5, st);
2949 print_statistics_on("SC Tier2", 6, st);
2950 print_statistics_on("SC Tier4", 8, st);
2951 print_statistics_on("SC Tier5 (preloaded)", 9, st);
2952 }
2953
2954 #define DO_COUNTERS(macro) \
2955 macro(Deoptimization, fetch_unroll_info) \
2956 macro(Deoptimization, unpack_frames) \
2957 macro(Deoptimization, uncommon_trap_inner) \
2958 macro(Deoptimization, uncommon_trap)
2959
2960 #define INIT_COUNTER(sub, name) \
2961 NEWPERFTICKCOUNTERS(_perf_##sub##_##name##_timer, SUN_RT, #sub "::" #name) \
2962 NEWPERFEVENTCOUNTER(_perf_##sub##_##name##_count, SUN_RT, #sub "::" #name "_count");
2963
2964 void Deoptimization::init_counters() {
2965 if (ProfileRuntimeCalls && UsePerfData) {
2966 EXCEPTION_MARK;
2967
2968 DO_COUNTERS(INIT_COUNTER)
2969
2970 if (HAS_PENDING_EXCEPTION) {
2971 vm_exit_during_initialization("jvm_perf_init failed unexpectedly");
2972 }
2973 }
2974 }
2975 #undef INIT_COUNTER
2976
2977 #define PRINT_COUNTER(sub, name) { \
2978 jlong count = _perf_##sub##_##name##_count->get_value(); \
2979 if (count > 0) { \
2980 st->print_cr(" %-50s = " JLONG_FORMAT_W(6) "us (elapsed) " JLONG_FORMAT_W(6) "us (thread) (" JLONG_FORMAT_W(5) " events)", #sub "::" #name, \
2981 _perf_##sub##_##name##_timer->elapsed_counter_value_us(), \
2982 _perf_##sub##_##name##_timer->thread_counter_value_us(), \
2983 count); \
2984 }}
2985
2986 void Deoptimization::print_counters_on(outputStream* st) {
2987 if (ProfileRuntimeCalls && UsePerfData) {
2988 DO_COUNTERS(PRINT_COUNTER)
2989 } else {
2990 st->print_cr(" Deoptimization: no info (%s is disabled)", (UsePerfData ? "ProfileRuntimeCalls" : "UsePerfData"));
2991 }
2992 }
2993
2994 #undef PRINT_COUNTER
2995 #undef DO_COUNTERS
2996
2997 #else // COMPILER2_OR_JVMCI
2998
2999
3000 // Stubs for C1 only system.
3001 bool Deoptimization::trap_state_is_recompiled(int trap_state) {
3002 return false;
3003 }
3004
3005 const char* Deoptimization::trap_reason_name(int reason) {
3006 return "unknown";
3007 }
3008
3009 jint Deoptimization::total_deoptimization_count() {
3010 return 0;
3011 }
3012
3013 jint Deoptimization::deoptimization_count(const char *reason_str, const char *action_str) {
3014 return 0;
3015 }
3016
3017 void Deoptimization::print_statistics() {
3018 // no output
3019 }
3020
3021 void
3022 Deoptimization::update_method_data_from_interpreter(MethodData* trap_mdo, int trap_bci, int reason) {
3023 // no update
3024 }
3025
3026 int Deoptimization::trap_state_has_reason(int trap_state, int reason) {
3027 return 0;
3028 }
3029
3030 void Deoptimization::gather_statistics(nmethod* nm, DeoptReason reason, DeoptAction action,
3031 Bytecodes::Code bc) {
3032 // no update
3033 }
3034
3035 const char* Deoptimization::format_trap_state(char* buf, size_t buflen,
3036 int trap_state) {
3037 jio_snprintf(buf, buflen, "#%d", trap_state);
3038 return buf;
3039 }
3040
3041 void Deoptimization::init_counters() {
3042 // nothing to do
3043 }
3044
3045 void Deoptimization::print_counters_on(outputStream* st) {
3046 // no output
3047 }
3048
3049 void Deoptimization::print_statistics_on(outputStream* st) {
3050 // no output
3051 }
3052
3053 #endif // COMPILER2_OR_JVMCI