1 /*
2 * Copyright (c) 1997, 2025, 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 "classfile/javaClasses.inline.hpp"
26 #include "classfile/symbolTable.hpp"
27 #include "classfile/systemDictionary.hpp"
28 #include "classfile/vmClasses.hpp"
29 #include "code/codeCache.hpp"
30 #include "code/debugInfoRec.hpp"
31 #include "code/nmethod.hpp"
32 #include "code/pcDesc.hpp"
33 #include "code/scopeDesc.hpp"
34 #include "compiler/compilationPolicy.hpp"
35 #include "compiler/compilerDefinitions.inline.hpp"
36 #include "gc/shared/collectedHeap.hpp"
37 #include "gc/shared/memAllocator.hpp"
38 #include "interpreter/bytecode.hpp"
39 #include "interpreter/bytecode.inline.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("%zd ", 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 (%zu 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 guarantee(compiled_method != nullptr, "deopt must be associated with an nmethod");
383 bool is_jvmci = compiled_method->is_compiled_by_jvmci();
384 Deoptimization::reassign_fields(&deoptee, &map, objects, realloc_failures, is_jvmci);
385 if (TraceDeoptimization) {
386 print_objects(deoptee_thread, objects, realloc_failures);
387 }
388 }
389 if (save_oop_result) {
390 // Restore result.
391 deoptee.set_saved_oop_result(&map, return_value());
392 }
393 return realloc_failures;
394 }
395
396 static void restore_eliminated_locks(JavaThread* thread, GrowableArray<compiledVFrame*>* chunk, bool realloc_failures,
397 frame& deoptee, int exec_mode, bool& deoptimized_objects) {
398 JavaThread* deoptee_thread = chunk->at(0)->thread();
399 assert(!EscapeBarrier::objs_are_deoptimized(deoptee_thread, deoptee.id()), "must relock just once");
400 assert(thread == Thread::current(), "should be");
401 HandleMark hm(thread);
402 #ifndef PRODUCT
403 bool first = true;
404 #endif // !PRODUCT
405 // Start locking from outermost/oldest frame
406 for (int i = (chunk->length() - 1); i >= 0; i--) {
407 compiledVFrame* cvf = chunk->at(i);
408 assert (cvf->scope() != nullptr,"expect only compiled java frames");
409 GrowableArray<MonitorInfo*>* monitors = cvf->monitors();
410 if (monitors->is_nonempty()) {
411 bool relocked = Deoptimization::relock_objects(thread, monitors, deoptee_thread, deoptee,
412 exec_mode, realloc_failures);
413 deoptimized_objects = deoptimized_objects || relocked;
414 #ifndef PRODUCT
415 if (PrintDeoptimizationDetails) {
416 ResourceMark rm;
417 stringStream st;
418 for (int j = 0; j < monitors->length(); j++) {
419 MonitorInfo* mi = monitors->at(j);
420 if (mi->eliminated()) {
421 if (first) {
422 first = false;
423 st.print_cr("RELOCK OBJECTS in thread " INTPTR_FORMAT, p2i(thread));
424 }
425 if (exec_mode == Deoptimization::Unpack_none) {
426 ObjectMonitor* monitor = deoptee_thread->current_waiting_monitor();
427 if (monitor != nullptr && monitor->object() == mi->owner()) {
428 st.print_cr(" object <" INTPTR_FORMAT "> DEFERRED relocking after wait", p2i(mi->owner()));
429 continue;
430 }
431 }
432 if (mi->owner_is_scalar_replaced()) {
433 Klass* k = java_lang_Class::as_Klass(mi->owner_klass());
434 st.print_cr(" failed reallocation for klass %s", k->external_name());
435 } else {
436 st.print_cr(" object <" INTPTR_FORMAT "> locked", p2i(mi->owner()));
437 }
438 }
439 }
440 tty->print_raw(st.freeze());
441 }
442 #endif // !PRODUCT
443 }
444 }
445 }
446
447 // Deoptimize objects, that is reallocate and relock them, just before they escape through JVMTI.
448 // The given vframes cover one physical frame.
449 bool Deoptimization::deoptimize_objects_internal(JavaThread* thread, GrowableArray<compiledVFrame*>* chunk,
450 bool& realloc_failures) {
451 frame deoptee = chunk->at(0)->fr();
452 JavaThread* deoptee_thread = chunk->at(0)->thread();
453 nmethod* nm = deoptee.cb()->as_nmethod_or_null();
454 RegisterMap map(chunk->at(0)->register_map());
455 bool deoptimized_objects = false;
456
457 bool const jvmci_enabled = JVMCI_ONLY(EnableJVMCI) NOT_JVMCI(false);
458
459 // Reallocate the non-escaping objects and restore their fields.
460 if (jvmci_enabled COMPILER2_PRESENT(|| (DoEscapeAnalysis && EliminateAllocations)
461 || EliminateAutoBox || EnableVectorAggressiveReboxing)) {
462 realloc_failures = rematerialize_objects(thread, Unpack_none, nm, deoptee, map, chunk, deoptimized_objects);
463 }
464
465 // MonitorInfo structures used in eliminate_locks are not GC safe.
466 NoSafepointVerifier no_safepoint;
467
468 // Now relock objects if synchronization on them was eliminated.
469 if (jvmci_enabled COMPILER2_PRESENT(|| ((DoEscapeAnalysis || EliminateNestedLocks) && EliminateLocks))) {
470 restore_eliminated_locks(thread, chunk, realloc_failures, deoptee, Unpack_none, deoptimized_objects);
471 }
472 return deoptimized_objects;
473 }
474 #endif // COMPILER2_OR_JVMCI
475
476 // This is factored, since it is both called from a JRT_LEAF (deoptimization) and a JRT_ENTRY (uncommon_trap)
477 Deoptimization::UnrollBlock* Deoptimization::fetch_unroll_info_helper(JavaThread* current, int exec_mode) {
478 // When we get here we are about to unwind the deoptee frame. In order to
479 // catch not yet safe to use frames, the following stack watermark barrier
480 // poll will make such frames safe to use.
481 StackWatermarkSet::before_unwind(current);
482
483 // Note: there is a safepoint safety issue here. No matter whether we enter
484 // via vanilla deopt or uncommon trap we MUST NOT stop at a safepoint once
485 // the vframeArray is created.
486 //
487
488 // Allocate our special deoptimization ResourceMark
489 DeoptResourceMark* dmark = new DeoptResourceMark(current);
490 assert(current->deopt_mark() == nullptr, "Pending deopt!");
491 current->set_deopt_mark(dmark);
492
493 frame stub_frame = current->last_frame(); // Makes stack walkable as side effect
494 RegisterMap map(current,
495 RegisterMap::UpdateMap::include,
496 RegisterMap::ProcessFrames::include,
497 RegisterMap::WalkContinuation::skip);
498 RegisterMap dummy_map(current,
499 RegisterMap::UpdateMap::skip,
500 RegisterMap::ProcessFrames::include,
501 RegisterMap::WalkContinuation::skip);
502 // Now get the deoptee with a valid map
503 frame deoptee = stub_frame.sender(&map);
504 // Set the deoptee nmethod
505 assert(current->deopt_compiled_method() == nullptr, "Pending deopt!");
506 nmethod* nm = deoptee.cb()->as_nmethod_or_null();
507 current->set_deopt_compiled_method(nm);
508
509 if (VerifyStack) {
510 current->validate_frame_layout();
511 }
512
513 // Create a growable array of VFrames where each VFrame represents an inlined
514 // Java frame. This storage is allocated with the usual system arena.
515 assert(deoptee.is_compiled_frame(), "Wrong frame type");
516 GrowableArray<compiledVFrame*>* chunk = new GrowableArray<compiledVFrame*>(10);
517 vframe* vf = vframe::new_vframe(&deoptee, &map, current);
518 while (!vf->is_top()) {
519 assert(vf->is_compiled_frame(), "Wrong frame type");
520 chunk->push(compiledVFrame::cast(vf));
521 vf = vf->sender();
522 }
523 assert(vf->is_compiled_frame(), "Wrong frame type");
524 chunk->push(compiledVFrame::cast(vf));
525
526 bool realloc_failures = false;
527
528 #if COMPILER2_OR_JVMCI
529 bool const jvmci_enabled = JVMCI_ONLY(EnableJVMCI) NOT_JVMCI(false);
530
531 // Reallocate the non-escaping objects and restore their fields. Then
532 // relock objects if synchronization on them was eliminated.
533 if (jvmci_enabled COMPILER2_PRESENT( || (DoEscapeAnalysis && EliminateAllocations)
534 || EliminateAutoBox || EnableVectorAggressiveReboxing )) {
535 bool unused;
536 realloc_failures = rematerialize_objects(current, exec_mode, nm, deoptee, map, chunk, unused);
537 }
538 #endif // COMPILER2_OR_JVMCI
539
540 // Ensure that no safepoint is taken after pointers have been stored
541 // in fields of rematerialized objects. If a safepoint occurs from here on
542 // out the java state residing in the vframeArray will be missed.
543 // Locks may be rebaised in a safepoint.
544 NoSafepointVerifier no_safepoint;
545
546 #if COMPILER2_OR_JVMCI
547 if ((jvmci_enabled COMPILER2_PRESENT( || ((DoEscapeAnalysis || EliminateNestedLocks) && EliminateLocks) ))
548 && !EscapeBarrier::objs_are_deoptimized(current, deoptee.id())) {
549 bool unused = false;
550 restore_eliminated_locks(current, chunk, realloc_failures, deoptee, exec_mode, unused);
551 }
552 #endif // COMPILER2_OR_JVMCI
553
554 ScopeDesc* trap_scope = chunk->at(0)->scope();
555 Handle exceptionObject;
556 if (trap_scope->rethrow_exception()) {
557 #ifndef PRODUCT
558 if (PrintDeoptimizationDetails) {
559 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());
560 }
561 #endif // !PRODUCT
562
563 GrowableArray<ScopeValue*>* expressions = trap_scope->expressions();
564 guarantee(expressions != nullptr && expressions->length() > 0, "must have exception to throw");
565 ScopeValue* topOfStack = expressions->top();
566 exceptionObject = StackValue::create_stack_value(&deoptee, &map, topOfStack)->get_obj();
567 guarantee(exceptionObject() != nullptr, "exception oop can not be null");
568 }
569
570 vframeArray* array = create_vframeArray(current, deoptee, &map, chunk, realloc_failures);
571 #if COMPILER2_OR_JVMCI
572 if (realloc_failures) {
573 // This destroys all ScopedValue bindings.
574 current->clear_scopedValueBindings();
575 pop_frames_failed_reallocs(current, array);
576 }
577 #endif
578
579 assert(current->vframe_array_head() == nullptr, "Pending deopt!");
580 current->set_vframe_array_head(array);
581
582 // Now that the vframeArray has been created if we have any deferred local writes
583 // added by jvmti then we can free up that structure as the data is now in the
584 // vframeArray
585
586 JvmtiDeferredUpdates::delete_updates_for_frame(current, array->original().id());
587
588 // Compute the caller frame based on the sender sp of stub_frame and stored frame sizes info.
589 CodeBlob* cb = stub_frame.cb();
590 // Verify we have the right vframeArray
591 assert(cb->frame_size() >= 0, "Unexpected frame size");
592 intptr_t* unpack_sp = stub_frame.sp() + cb->frame_size();
593
594 // If the deopt call site is a MethodHandle invoke call site we have
595 // to adjust the unpack_sp.
596 nmethod* deoptee_nm = deoptee.cb()->as_nmethod_or_null();
597 if (deoptee_nm != nullptr && deoptee_nm->is_method_handle_return(deoptee.pc()))
598 unpack_sp = deoptee.unextended_sp();
599
600 #ifdef ASSERT
601 assert(cb->is_deoptimization_stub() ||
602 cb->is_uncommon_trap_stub() ||
603 strcmp("Stub<DeoptimizationStub.deoptimizationHandler>", cb->name()) == 0 ||
604 strcmp("Stub<UncommonTrapStub.uncommonTrapHandler>", cb->name()) == 0,
605 "unexpected code blob: %s", cb->name());
606 #endif
607
608 // This is a guarantee instead of an assert because if vframe doesn't match
609 // we will unpack the wrong deoptimized frame and wind up in strange places
610 // where it will be very difficult to figure out what went wrong. Better
611 // to die an early death here than some very obscure death later when the
612 // trail is cold.
613 guarantee(array->unextended_sp() == unpack_sp, "vframe_array_head must contain the vframeArray to unpack");
614
615 int number_of_frames = array->frames();
616
617 // Compute the vframes' sizes. Note that frame_sizes[] entries are ordered from outermost to innermost
618 // virtual activation, which is the reverse of the elements in the vframes array.
619 intptr_t* frame_sizes = NEW_C_HEAP_ARRAY(intptr_t, number_of_frames, mtCompiler);
620 // +1 because we always have an interpreter return address for the final slot.
621 address* frame_pcs = NEW_C_HEAP_ARRAY(address, number_of_frames + 1, mtCompiler);
622 int popframe_extra_args = 0;
623 // Create an interpreter return address for the stub to use as its return
624 // address so the skeletal frames are perfectly walkable
625 frame_pcs[number_of_frames] = Interpreter::deopt_entry(vtos, 0);
626
627 // PopFrame requires that the preserved incoming arguments from the recently-popped topmost
628 // activation be put back on the expression stack of the caller for reexecution
629 if (JvmtiExport::can_pop_frame() && current->popframe_forcing_deopt_reexecution()) {
630 popframe_extra_args = in_words(current->popframe_preserved_args_size_in_words());
631 }
632
633 // Find the current pc for sender of the deoptee. Since the sender may have been deoptimized
634 // itself since the deoptee vframeArray was created we must get a fresh value of the pc rather
635 // than simply use array->sender.pc(). This requires us to walk the current set of frames
636 //
637 frame deopt_sender = stub_frame.sender(&dummy_map); // First is the deoptee frame
638 deopt_sender = deopt_sender.sender(&dummy_map); // Now deoptee caller
639
640 // It's possible that the number of parameters at the call site is
641 // different than number of arguments in the callee when method
642 // handles are used. If the caller is interpreted get the real
643 // value so that the proper amount of space can be added to it's
644 // frame.
645 bool caller_was_method_handle = false;
646 if (deopt_sender.is_interpreted_frame()) {
647 methodHandle method(current, deopt_sender.interpreter_frame_method());
648 Bytecode_invoke cur(method, deopt_sender.interpreter_frame_bci());
649 if (cur.has_member_arg()) {
650 // This should cover all real-world cases. One exception is a pathological chain of
651 // MH.linkToXXX() linker calls, which only trusted code could do anyway. To handle that case, we
652 // would need to get the size from the resolved method entry. Another exception would
653 // be an invokedynamic with an adapter that is really a MethodHandle linker.
654 caller_was_method_handle = true;
655 }
656 }
657
658 //
659 // frame_sizes/frame_pcs[0] oldest frame (int or c2i)
660 // frame_sizes/frame_pcs[1] next oldest frame (int)
661 // frame_sizes/frame_pcs[n] youngest frame (int)
662 //
663 // Now a pc in frame_pcs is actually the return address to the frame's caller (a frame
664 // owns the space for the return address to it's caller). Confusing ain't it.
665 //
666 // The vframe array can address vframes with indices running from
667 // 0.._frames-1. Index 0 is the youngest frame and _frame - 1 is the oldest (root) frame.
668 // When we create the skeletal frames we need the oldest frame to be in the zero slot
669 // in the frame_sizes/frame_pcs so the assembly code can do a trivial walk.
670 // so things look a little strange in this loop.
671 //
672 int callee_parameters = 0;
673 int callee_locals = 0;
674 for (int index = 0; index < array->frames(); index++ ) {
675 // frame[number_of_frames - 1 ] = on_stack_size(youngest)
676 // frame[number_of_frames - 2 ] = on_stack_size(sender(youngest))
677 // frame[number_of_frames - 3 ] = on_stack_size(sender(sender(youngest)))
678 frame_sizes[number_of_frames - 1 - index] = BytesPerWord * array->element(index)->on_stack_size(callee_parameters,
679 callee_locals,
680 index == 0,
681 popframe_extra_args);
682 // This pc doesn't have to be perfect just good enough to identify the frame
683 // as interpreted so the skeleton frame will be walkable
684 // The correct pc will be set when the skeleton frame is completely filled out
685 // The final pc we store in the loop is wrong and will be overwritten below
686 frame_pcs[number_of_frames - 1 - index ] = Interpreter::deopt_entry(vtos, 0) - frame::pc_return_offset;
687
688 callee_parameters = array->element(index)->method()->size_of_parameters();
689 callee_locals = array->element(index)->method()->max_locals();
690 popframe_extra_args = 0;
691 }
692
693 // Compute whether the root vframe returns a float or double value.
694 BasicType return_type;
695 {
696 methodHandle method(current, array->element(0)->method());
697 Bytecode_invoke invoke = Bytecode_invoke_check(method, array->element(0)->bci());
698 return_type = invoke.is_valid() ? invoke.result_type() : T_ILLEGAL;
699 }
700
701 // Compute information for handling adapters and adjusting the frame size of the caller.
702 int caller_adjustment = 0;
703
704 // Compute the amount the oldest interpreter frame will have to adjust
705 // its caller's stack by. If the caller is a compiled frame then
706 // we pretend that the callee has no parameters so that the
707 // extension counts for the full amount of locals and not just
708 // locals-parms. This is because without a c2i adapter the parm
709 // area as created by the compiled frame will not be usable by
710 // the interpreter. (Depending on the calling convention there
711 // may not even be enough space).
712
713 // QQQ I'd rather see this pushed down into last_frame_adjust
714 // and have it take the sender (aka caller).
715
716 if (!deopt_sender.is_interpreted_frame() || caller_was_method_handle) {
717 caller_adjustment = last_frame_adjust(0, callee_locals);
718 } else if (callee_locals > callee_parameters) {
719 // The caller frame may need extending to accommodate
720 // non-parameter locals of the first unpacked interpreted frame.
721 // Compute that adjustment.
722 caller_adjustment = last_frame_adjust(callee_parameters, callee_locals);
723 }
724
725 // If the sender is deoptimized the we must retrieve the address of the handler
726 // since the frame will "magically" show the original pc before the deopt
727 // and we'd undo the deopt.
728
729 frame_pcs[0] = Continuation::is_cont_barrier_frame(deoptee) ? StubRoutines::cont_returnBarrier() : deopt_sender.raw_pc();
730 if (Continuation::is_continuation_enterSpecial(deopt_sender)) {
731 ContinuationEntry::from_frame(deopt_sender)->set_argsize(0);
732 }
733
734 assert(CodeCache::find_blob(frame_pcs[0]) != nullptr, "bad pc");
735
736 #if INCLUDE_JVMCI
737 if (exceptionObject() != nullptr) {
738 current->set_exception_oop(exceptionObject());
739 exec_mode = Unpack_exception;
740 }
741 #endif
742
743 if (current->frames_to_pop_failed_realloc() > 0 && exec_mode != Unpack_uncommon_trap) {
744 assert(current->has_pending_exception(), "should have thrown OOME");
745 current->set_exception_oop(current->pending_exception());
746 current->clear_pending_exception();
747 exec_mode = Unpack_exception;
748 }
749
750 #if INCLUDE_JVMCI
751 if (current->frames_to_pop_failed_realloc() > 0) {
752 current->set_pending_monitorenter(false);
753 }
754 #endif
755
756 int caller_actual_parameters = -1; // value not used except for interpreted frames, see below
757 if (deopt_sender.is_interpreted_frame()) {
758 caller_actual_parameters = callee_parameters + (caller_was_method_handle ? 1 : 0);
759 }
760
761 UnrollBlock* info = new UnrollBlock(array->frame_size() * BytesPerWord,
762 caller_adjustment * BytesPerWord,
763 caller_actual_parameters,
764 number_of_frames,
765 frame_sizes,
766 frame_pcs,
767 return_type,
768 exec_mode);
769 // On some platforms, we need a way to pass some platform dependent
770 // information to the unpacking code so the skeletal frames come out
771 // correct (initial fp value, unextended sp, ...)
772 info->set_initial_info((intptr_t) array->sender().initial_deoptimization_info());
773
774 if (array->frames() > 1) {
775 if (VerifyStack && TraceDeoptimization) {
776 tty->print_cr("Deoptimizing method containing inlining");
777 }
778 }
779
780 array->set_unroll_block(info);
781 return info;
782 }
783
784 // Called to cleanup deoptimization data structures in normal case
785 // after unpacking to stack and when stack overflow error occurs
786 void Deoptimization::cleanup_deopt_info(JavaThread *thread,
787 vframeArray *array) {
788
789 // Get array if coming from exception
790 if (array == nullptr) {
791 array = thread->vframe_array_head();
792 }
793 thread->set_vframe_array_head(nullptr);
794
795 // Free the previous UnrollBlock
796 vframeArray* old_array = thread->vframe_array_last();
797 thread->set_vframe_array_last(array);
798
799 if (old_array != nullptr) {
800 UnrollBlock* old_info = old_array->unroll_block();
801 old_array->set_unroll_block(nullptr);
802 delete old_info;
803 delete old_array;
804 }
805
806 // Deallocate any resource creating in this routine and any ResourceObjs allocated
807 // inside the vframeArray (StackValueCollections)
808
809 delete thread->deopt_mark();
810 thread->set_deopt_mark(nullptr);
811 thread->set_deopt_compiled_method(nullptr);
812
813
814 if (JvmtiExport::can_pop_frame()) {
815 // Regardless of whether we entered this routine with the pending
816 // popframe condition bit set, we should always clear it now
817 thread->clear_popframe_condition();
818 }
819
820 // unpack_frames() is called at the end of the deoptimization handler
821 // and (in C2) at the end of the uncommon trap handler. Note this fact
822 // so that an asynchronous stack walker can work again. This counter is
823 // incremented at the beginning of fetch_unroll_info() and (in C2) at
824 // the beginning of uncommon_trap().
825 thread->dec_in_deopt_handler();
826 }
827
828 // Moved from cpu directories because none of the cpus has callee save values.
829 // If a cpu implements callee save values, move this to deoptimization_<cpu>.cpp.
830 void Deoptimization::unwind_callee_save_values(frame* f, vframeArray* vframe_array) {
831
832 // This code is sort of the equivalent of C2IAdapter::setup_stack_frame back in
833 // the days we had adapter frames. When we deoptimize a situation where a
834 // compiled caller calls a compiled caller will have registers it expects
835 // to survive the call to the callee. If we deoptimize the callee the only
836 // way we can restore these registers is to have the oldest interpreter
837 // frame that we create restore these values. That is what this routine
838 // will accomplish.
839
840 // At the moment we have modified c2 to not have any callee save registers
841 // so this problem does not exist and this routine is just a place holder.
842
843 assert(f->is_interpreted_frame(), "must be interpreted");
844 }
845
846 #ifndef PRODUCT
847 static bool falls_through(Bytecodes::Code bc) {
848 switch (bc) {
849 // List may be incomplete. Here we really only care about bytecodes where compiled code
850 // can deoptimize.
851 case Bytecodes::_goto:
852 case Bytecodes::_goto_w:
853 case Bytecodes::_athrow:
854 return false;
855 default:
856 return true;
857 }
858 }
859 #endif
860
861 // Return BasicType of value being returned
862 JRT_LEAF_PROF_NO_THREAD(BasicType, Deoptimization, unpack_frames, Deoptimization::unpack_frames(JavaThread* thread, int exec_mode))
863 assert(thread == JavaThread::current(), "pre-condition");
864
865 // We are already active in the special DeoptResourceMark any ResourceObj's we
866 // allocate will be freed at the end of the routine.
867
868 // JRT_LEAF methods don't normally allocate handles and there is a
869 // NoHandleMark to enforce that. It is actually safe to use Handles
870 // in a JRT_LEAF method, and sometimes desirable, but to do so we
871 // must use ResetNoHandleMark to bypass the NoHandleMark, and
872 // then use a HandleMark to ensure any Handles we do create are
873 // cleaned up in this scope.
874 ResetNoHandleMark rnhm;
875 HandleMark hm(thread);
876
877 frame stub_frame = thread->last_frame();
878
879 Continuation::notify_deopt(thread, stub_frame.sp());
880
881 // Since the frame to unpack is the top frame of this thread, the vframe_array_head
882 // must point to the vframeArray for the unpack frame.
883 vframeArray* array = thread->vframe_array_head();
884 UnrollBlock* info = array->unroll_block();
885
886 // We set the last_Java frame. But the stack isn't really parsable here. So we
887 // clear it to make sure JFR understands not to try and walk stacks from events
888 // in here.
889 intptr_t* sp = thread->frame_anchor()->last_Java_sp();
890 thread->frame_anchor()->set_last_Java_sp(nullptr);
891
892 // Unpack the interpreter frames and any adapter frame (c2 only) we might create.
893 array->unpack_to_stack(stub_frame, exec_mode, info->caller_actual_parameters());
894
895 thread->frame_anchor()->set_last_Java_sp(sp);
896
897 BasicType bt = info->return_type();
898
899 // If we have an exception pending, claim that the return type is an oop
900 // so the deopt_blob does not overwrite the exception_oop.
901
902 if (exec_mode == Unpack_exception)
903 bt = T_OBJECT;
904
905 // Cleanup thread deopt data
906 cleanup_deopt_info(thread, array);
907
908 #ifndef PRODUCT
909 if (VerifyStack) {
910 ResourceMark res_mark;
911 // Clear pending exception to not break verification code (restored afterwards)
912 PreserveExceptionMark pm(thread);
913
914 thread->validate_frame_layout();
915
916 // Verify that the just-unpacked frames match the interpreter's
917 // notions of expression stack and locals
918 vframeArray* cur_array = thread->vframe_array_last();
919 RegisterMap rm(thread,
920 RegisterMap::UpdateMap::skip,
921 RegisterMap::ProcessFrames::include,
922 RegisterMap::WalkContinuation::skip);
923 rm.set_include_argument_oops(false);
924 bool is_top_frame = true;
925 int callee_size_of_parameters = 0;
926 int callee_max_locals = 0;
927 for (int i = 0; i < cur_array->frames(); i++) {
928 vframeArrayElement* el = cur_array->element(i);
929 frame* iframe = el->iframe();
930 guarantee(iframe->is_interpreted_frame(), "Wrong frame type");
931
932 // Get the oop map for this bci
933 InterpreterOopMap mask;
934 int cur_invoke_parameter_size = 0;
935 bool try_next_mask = false;
936 int next_mask_expression_stack_size = -1;
937 int top_frame_expression_stack_adjustment = 0;
938 methodHandle mh(thread, iframe->interpreter_frame_method());
939 OopMapCache::compute_one_oop_map(mh, iframe->interpreter_frame_bci(), &mask);
940 BytecodeStream str(mh, iframe->interpreter_frame_bci());
941 int max_bci = mh->code_size();
942 // Get to the next bytecode if possible
943 assert(str.bci() < max_bci, "bci in interpreter frame out of bounds");
944 // Check to see if we can grab the number of outgoing arguments
945 // at an uncommon trap for an invoke (where the compiler
946 // generates debug info before the invoke has executed)
947 Bytecodes::Code cur_code = str.next();
948 Bytecodes::Code next_code = Bytecodes::_shouldnotreachhere;
949 if (Bytecodes::is_invoke(cur_code)) {
950 Bytecode_invoke invoke(mh, iframe->interpreter_frame_bci());
951 cur_invoke_parameter_size = invoke.size_of_parameters();
952 if (i != 0 && invoke.has_member_arg()) {
953 callee_size_of_parameters++;
954 }
955 }
956 if (str.bci() < max_bci) {
957 next_code = str.next();
958 if (next_code >= 0) {
959 // The interpreter oop map generator reports results before
960 // the current bytecode has executed except in the case of
961 // calls. It seems to be hard to tell whether the compiler
962 // has emitted debug information matching the "state before"
963 // a given bytecode or the state after, so we try both
964 if (!Bytecodes::is_invoke(cur_code) && falls_through(cur_code)) {
965 // Get expression stack size for the next bytecode
966 InterpreterOopMap next_mask;
967 OopMapCache::compute_one_oop_map(mh, str.bci(), &next_mask);
968 next_mask_expression_stack_size = next_mask.expression_stack_size();
969 if (Bytecodes::is_invoke(next_code)) {
970 Bytecode_invoke invoke(mh, str.bci());
971 next_mask_expression_stack_size += invoke.size_of_parameters();
972 }
973 // Need to subtract off the size of the result type of
974 // the bytecode because this is not described in the
975 // debug info but returned to the interpreter in the TOS
976 // caching register
977 BasicType bytecode_result_type = Bytecodes::result_type(cur_code);
978 if (bytecode_result_type != T_ILLEGAL) {
979 top_frame_expression_stack_adjustment = type2size[bytecode_result_type];
980 }
981 assert(top_frame_expression_stack_adjustment >= 0, "stack adjustment must be positive");
982 try_next_mask = true;
983 }
984 }
985 }
986
987 // Verify stack depth and oops in frame
988 // This assertion may be dependent on the platform we're running on and may need modification (tested on x86 and sparc)
989 if (!(
990 /* SPARC */
991 (iframe->interpreter_frame_expression_stack_size() == mask.expression_stack_size() + callee_size_of_parameters) ||
992 /* x86 */
993 (iframe->interpreter_frame_expression_stack_size() == mask.expression_stack_size() + callee_max_locals) ||
994 (try_next_mask &&
995 (iframe->interpreter_frame_expression_stack_size() == (next_mask_expression_stack_size -
996 top_frame_expression_stack_adjustment))) ||
997 (is_top_frame && (exec_mode == Unpack_exception) && iframe->interpreter_frame_expression_stack_size() == 0) ||
998 (is_top_frame && (exec_mode == Unpack_uncommon_trap || exec_mode == Unpack_reexecute || el->should_reexecute()) &&
999 (iframe->interpreter_frame_expression_stack_size() == mask.expression_stack_size() + cur_invoke_parameter_size))
1000 )) {
1001 {
1002 // Print out some information that will help us debug the problem
1003 tty->print_cr("Wrong number of expression stack elements during deoptimization");
1004 tty->print_cr(" Error occurred while verifying frame %d (0..%d, 0 is topmost)", i, cur_array->frames() - 1);
1005 tty->print_cr(" Current code %s", Bytecodes::name(cur_code));
1006 if (try_next_mask) {
1007 tty->print_cr(" Next code %s", Bytecodes::name(next_code));
1008 }
1009 tty->print_cr(" Fabricated interpreter frame had %d expression stack elements",
1010 iframe->interpreter_frame_expression_stack_size());
1011 tty->print_cr(" Interpreter oop map had %d expression stack elements", mask.expression_stack_size());
1012 tty->print_cr(" try_next_mask = %d", try_next_mask);
1013 tty->print_cr(" next_mask_expression_stack_size = %d", next_mask_expression_stack_size);
1014 tty->print_cr(" callee_size_of_parameters = %d", callee_size_of_parameters);
1015 tty->print_cr(" callee_max_locals = %d", callee_max_locals);
1016 tty->print_cr(" top_frame_expression_stack_adjustment = %d", top_frame_expression_stack_adjustment);
1017 tty->print_cr(" exec_mode = %d", exec_mode);
1018 tty->print_cr(" cur_invoke_parameter_size = %d", cur_invoke_parameter_size);
1019 tty->print_cr(" Thread = " INTPTR_FORMAT ", thread ID = %d", p2i(thread), thread->osthread()->thread_id());
1020 tty->print_cr(" Interpreted frames:");
1021 for (int k = 0; k < cur_array->frames(); k++) {
1022 vframeArrayElement* el = cur_array->element(k);
1023 tty->print_cr(" %s (bci %d)", el->method()->name_and_sig_as_C_string(), el->bci());
1024 }
1025 cur_array->print_on_2(tty);
1026 }
1027 guarantee(false, "wrong number of expression stack elements during deopt");
1028 }
1029 VerifyOopClosure verify;
1030 iframe->oops_interpreted_do(&verify, &rm, false);
1031 callee_size_of_parameters = mh->size_of_parameters();
1032 callee_max_locals = mh->max_locals();
1033 is_top_frame = false;
1034 }
1035 }
1036 #endif // !PRODUCT
1037
1038 return bt;
1039 JRT_END
1040
1041 class DeoptimizeMarkedClosure : public HandshakeClosure {
1042 public:
1043 DeoptimizeMarkedClosure() : HandshakeClosure("Deoptimize") {}
1044 void do_thread(Thread* thread) {
1045 JavaThread* jt = JavaThread::cast(thread);
1046 jt->deoptimize_marked_methods();
1047 }
1048 };
1049
1050 void Deoptimization::deoptimize_all_marked() {
1051 ResourceMark rm;
1052
1053 // Make the dependent methods not entrant
1054 CodeCache::make_marked_nmethods_deoptimized();
1055
1056 DeoptimizeMarkedClosure deopt;
1057 if (SafepointSynchronize::is_at_safepoint()) {
1058 Threads::java_threads_do(&deopt);
1059 } else {
1060 Handshake::execute(&deopt);
1061 }
1062 }
1063
1064 Deoptimization::DeoptAction Deoptimization::_unloaded_action
1065 = Deoptimization::Action_reinterpret;
1066
1067 #if INCLUDE_JVMCI
1068 template<typename CacheType>
1069 class BoxCacheBase : public CHeapObj<mtCompiler> {
1070 protected:
1071 static InstanceKlass* find_cache_klass(Thread* thread, Symbol* klass_name) {
1072 ResourceMark rm(thread);
1073 char* klass_name_str = klass_name->as_C_string();
1074 InstanceKlass* ik = SystemDictionary::find_instance_klass(thread, klass_name, Handle());
1075 guarantee(ik != nullptr, "%s must be loaded", klass_name_str);
1076 if (!ik->is_in_error_state()) {
1077 guarantee(ik->is_initialized(), "%s must be initialized", klass_name_str);
1078 CacheType::compute_offsets(ik);
1079 }
1080 return ik;
1081 }
1082 };
1083
1084 template<typename PrimitiveType, typename CacheType, typename BoxType> class BoxCache : public BoxCacheBase<CacheType> {
1085 PrimitiveType _low;
1086 PrimitiveType _high;
1087 jobject _cache;
1088 protected:
1089 static BoxCache<PrimitiveType, CacheType, BoxType> *_singleton;
1090 BoxCache(Thread* thread) {
1091 InstanceKlass* ik = BoxCacheBase<CacheType>::find_cache_klass(thread, CacheType::symbol());
1092 if (ik->is_in_error_state()) {
1093 _low = 1;
1094 _high = 0;
1095 _cache = nullptr;
1096 } else {
1097 objArrayOop cache = CacheType::cache(ik);
1098 assert(cache->length() > 0, "Empty cache");
1099 _low = BoxType::value(cache->obj_at(0));
1100 _high = checked_cast<PrimitiveType>(_low + cache->length() - 1);
1101 _cache = JNIHandles::make_global(Handle(thread, cache));
1102 }
1103 }
1104 ~BoxCache() {
1105 JNIHandles::destroy_global(_cache);
1106 }
1107 public:
1108 static BoxCache<PrimitiveType, CacheType, BoxType>* singleton(Thread* thread) {
1109 if (_singleton == nullptr) {
1110 BoxCache<PrimitiveType, CacheType, BoxType>* s = new BoxCache<PrimitiveType, CacheType, BoxType>(thread);
1111 if (!Atomic::replace_if_null(&_singleton, s)) {
1112 delete s;
1113 }
1114 }
1115 return _singleton;
1116 }
1117 oop lookup(PrimitiveType value) {
1118 if (_low <= value && value <= _high) {
1119 int offset = checked_cast<int>(value - _low);
1120 return objArrayOop(JNIHandles::resolve_non_null(_cache))->obj_at(offset);
1121 }
1122 return nullptr;
1123 }
1124 oop lookup_raw(intptr_t raw_value, bool& cache_init_error) {
1125 if (_cache == nullptr) {
1126 cache_init_error = true;
1127 return nullptr;
1128 }
1129 // Have to cast to avoid little/big-endian problems.
1130 if (sizeof(PrimitiveType) > sizeof(jint)) {
1131 jlong value = (jlong)raw_value;
1132 return lookup(value);
1133 }
1134 PrimitiveType value = (PrimitiveType)*((jint*)&raw_value);
1135 return lookup(value);
1136 }
1137 };
1138
1139 typedef BoxCache<jint, java_lang_Integer_IntegerCache, java_lang_Integer> IntegerBoxCache;
1140 typedef BoxCache<jlong, java_lang_Long_LongCache, java_lang_Long> LongBoxCache;
1141 typedef BoxCache<jchar, java_lang_Character_CharacterCache, java_lang_Character> CharacterBoxCache;
1142 typedef BoxCache<jshort, java_lang_Short_ShortCache, java_lang_Short> ShortBoxCache;
1143 typedef BoxCache<jbyte, java_lang_Byte_ByteCache, java_lang_Byte> ByteBoxCache;
1144
1145 template<> BoxCache<jint, java_lang_Integer_IntegerCache, java_lang_Integer>* BoxCache<jint, java_lang_Integer_IntegerCache, java_lang_Integer>::_singleton = nullptr;
1146 template<> BoxCache<jlong, java_lang_Long_LongCache, java_lang_Long>* BoxCache<jlong, java_lang_Long_LongCache, java_lang_Long>::_singleton = nullptr;
1147 template<> BoxCache<jchar, java_lang_Character_CharacterCache, java_lang_Character>* BoxCache<jchar, java_lang_Character_CharacterCache, java_lang_Character>::_singleton = nullptr;
1148 template<> BoxCache<jshort, java_lang_Short_ShortCache, java_lang_Short>* BoxCache<jshort, java_lang_Short_ShortCache, java_lang_Short>::_singleton = nullptr;
1149 template<> BoxCache<jbyte, java_lang_Byte_ByteCache, java_lang_Byte>* BoxCache<jbyte, java_lang_Byte_ByteCache, java_lang_Byte>::_singleton = nullptr;
1150
1151 class BooleanBoxCache : public BoxCacheBase<java_lang_Boolean> {
1152 jobject _true_cache;
1153 jobject _false_cache;
1154 protected:
1155 static BooleanBoxCache *_singleton;
1156 BooleanBoxCache(Thread *thread) {
1157 InstanceKlass* ik = find_cache_klass(thread, java_lang_Boolean::symbol());
1158 if (ik->is_in_error_state()) {
1159 _true_cache = nullptr;
1160 _false_cache = nullptr;
1161 } else {
1162 _true_cache = JNIHandles::make_global(Handle(thread, java_lang_Boolean::get_TRUE(ik)));
1163 _false_cache = JNIHandles::make_global(Handle(thread, java_lang_Boolean::get_FALSE(ik)));
1164 }
1165 }
1166 ~BooleanBoxCache() {
1167 JNIHandles::destroy_global(_true_cache);
1168 JNIHandles::destroy_global(_false_cache);
1169 }
1170 public:
1171 static BooleanBoxCache* singleton(Thread* thread) {
1172 if (_singleton == nullptr) {
1173 BooleanBoxCache* s = new BooleanBoxCache(thread);
1174 if (!Atomic::replace_if_null(&_singleton, s)) {
1175 delete s;
1176 }
1177 }
1178 return _singleton;
1179 }
1180 oop lookup_raw(intptr_t raw_value, bool& cache_in_error) {
1181 if (_true_cache == nullptr) {
1182 cache_in_error = true;
1183 return nullptr;
1184 }
1185 // Have to cast to avoid little/big-endian problems.
1186 jboolean value = (jboolean)*((jint*)&raw_value);
1187 return lookup(value);
1188 }
1189 oop lookup(jboolean value) {
1190 if (value != 0) {
1191 return JNIHandles::resolve_non_null(_true_cache);
1192 }
1193 return JNIHandles::resolve_non_null(_false_cache);
1194 }
1195 };
1196
1197 BooleanBoxCache* BooleanBoxCache::_singleton = nullptr;
1198
1199 oop Deoptimization::get_cached_box(AutoBoxObjectValue* bv, frame* fr, RegisterMap* reg_map, bool& cache_init_error, TRAPS) {
1200 Klass* k = java_lang_Class::as_Klass(bv->klass()->as_ConstantOopReadValue()->value()());
1201 BasicType box_type = vmClasses::box_klass_type(k);
1202 if (box_type != T_OBJECT) {
1203 StackValue* value = StackValue::create_stack_value(fr, reg_map, bv->field_at(box_type == T_LONG ? 1 : 0));
1204 switch(box_type) {
1205 case T_INT: return IntegerBoxCache::singleton(THREAD)->lookup_raw(value->get_intptr(), cache_init_error);
1206 case T_CHAR: return CharacterBoxCache::singleton(THREAD)->lookup_raw(value->get_intptr(), cache_init_error);
1207 case T_SHORT: return ShortBoxCache::singleton(THREAD)->lookup_raw(value->get_intptr(), cache_init_error);
1208 case T_BYTE: return ByteBoxCache::singleton(THREAD)->lookup_raw(value->get_intptr(), cache_init_error);
1209 case T_BOOLEAN: return BooleanBoxCache::singleton(THREAD)->lookup_raw(value->get_intptr(), cache_init_error);
1210 case T_LONG: return LongBoxCache::singleton(THREAD)->lookup_raw(value->get_intptr(), cache_init_error);
1211 default:;
1212 }
1213 }
1214 return nullptr;
1215 }
1216 #endif // INCLUDE_JVMCI
1217
1218 #if COMPILER2_OR_JVMCI
1219 bool Deoptimization::realloc_objects(JavaThread* thread, frame* fr, RegisterMap* reg_map, GrowableArray<ScopeValue*>* objects, TRAPS) {
1220 Handle pending_exception(THREAD, thread->pending_exception());
1221 const char* exception_file = thread->exception_file();
1222 int exception_line = thread->exception_line();
1223 thread->clear_pending_exception();
1224
1225 bool failures = false;
1226
1227 for (int i = 0; i < objects->length(); i++) {
1228 assert(objects->at(i)->is_object(), "invalid debug information");
1229 ObjectValue* sv = (ObjectValue*) objects->at(i);
1230
1231 Klass* k = java_lang_Class::as_Klass(sv->klass()->as_ConstantOopReadValue()->value()());
1232 oop obj = nullptr;
1233
1234 bool cache_init_error = false;
1235 if (k->is_instance_klass()) {
1236 #if INCLUDE_JVMCI
1237 nmethod* nm = fr->cb()->as_nmethod_or_null();
1238 if (nm->is_compiled_by_jvmci() && sv->is_auto_box()) {
1239 AutoBoxObjectValue* abv = (AutoBoxObjectValue*) sv;
1240 obj = get_cached_box(abv, fr, reg_map, cache_init_error, THREAD);
1241 if (obj != nullptr) {
1242 // Set the flag to indicate the box came from a cache, so that we can skip the field reassignment for it.
1243 abv->set_cached(true);
1244 } else if (cache_init_error) {
1245 // Results in an OOME which is valid (as opposed to a class initialization error)
1246 // and is fine for the rare case a cache initialization failing.
1247 failures = true;
1248 }
1249 }
1250 #endif // INCLUDE_JVMCI
1251
1252 InstanceKlass* ik = InstanceKlass::cast(k);
1253 if (obj == nullptr && !cache_init_error) {
1254 InternalOOMEMark iom(THREAD);
1255 if (EnableVectorSupport && VectorSupport::is_vector(ik)) {
1256 obj = VectorSupport::allocate_vector(ik, fr, reg_map, sv, THREAD);
1257 } else {
1258 obj = ik->allocate_instance(THREAD);
1259 }
1260 }
1261 } else if (k->is_typeArray_klass()) {
1262 TypeArrayKlass* ak = TypeArrayKlass::cast(k);
1263 assert(sv->field_size() % type2size[ak->element_type()] == 0, "non-integral array length");
1264 int len = sv->field_size() / type2size[ak->element_type()];
1265 InternalOOMEMark iom(THREAD);
1266 obj = ak->allocate(len, THREAD);
1267 } else if (k->is_objArray_klass()) {
1268 ObjArrayKlass* ak = ObjArrayKlass::cast(k);
1269 InternalOOMEMark iom(THREAD);
1270 obj = ak->allocate(sv->field_size(), THREAD);
1271 }
1272
1273 if (obj == nullptr) {
1274 failures = true;
1275 }
1276
1277 assert(sv->value().is_null(), "redundant reallocation");
1278 assert(obj != nullptr || HAS_PENDING_EXCEPTION || cache_init_error, "allocation should succeed or we should get an exception");
1279 CLEAR_PENDING_EXCEPTION;
1280 sv->set_value(obj);
1281 }
1282
1283 if (failures) {
1284 THROW_OOP_(Universe::out_of_memory_error_realloc_objects(), failures);
1285 } else if (pending_exception.not_null()) {
1286 thread->set_pending_exception(pending_exception(), exception_file, exception_line);
1287 }
1288
1289 return failures;
1290 }
1291
1292 #if INCLUDE_JVMCI
1293 /**
1294 * For primitive types whose kind gets "erased" at runtime (shorts become stack ints),
1295 * we need to somehow be able to recover the actual kind to be able to write the correct
1296 * amount of bytes.
1297 * For that purpose, this method assumes that, for an entry spanning n bytes at index i,
1298 * the entries at index n + 1 to n + i are 'markers'.
1299 * For example, if we were writing a short at index 4 of a byte array of size 8, the
1300 * expected form of the array would be:
1301 *
1302 * {b0, b1, b2, b3, INT, marker, b6, b7}
1303 *
1304 * Thus, in order to get back the size of the entry, we simply need to count the number
1305 * of marked entries
1306 *
1307 * @param virtualArray the virtualized byte array
1308 * @param i index of the virtual entry we are recovering
1309 * @return The number of bytes the entry spans
1310 */
1311 static int count_number_of_bytes_for_entry(ObjectValue *virtualArray, int i) {
1312 int index = i;
1313 while (++index < virtualArray->field_size() &&
1314 virtualArray->field_at(index)->is_marker()) {}
1315 return index - i;
1316 }
1317
1318 /**
1319 * If there was a guarantee for byte array to always start aligned to a long, we could
1320 * do a simple check on the parity of the index. Unfortunately, that is not always the
1321 * case. Thus, we check alignment of the actual address we are writing to.
1322 * In the unlikely case index 0 is 5-aligned for example, it would then be possible to
1323 * write a long to index 3.
1324 */
1325 static jbyte* check_alignment_get_addr(typeArrayOop obj, int index, int expected_alignment) {
1326 jbyte* res = obj->byte_at_addr(index);
1327 assert((((intptr_t) res) % expected_alignment) == 0, "Non-aligned write");
1328 return res;
1329 }
1330
1331 static void byte_array_put(typeArrayOop obj, StackValue* value, int index, int byte_count) {
1332 switch (byte_count) {
1333 case 1:
1334 obj->byte_at_put(index, (jbyte) value->get_jint());
1335 break;
1336 case 2:
1337 *((jshort *) check_alignment_get_addr(obj, index, 2)) = (jshort) value->get_jint();
1338 break;
1339 case 4:
1340 *((jint *) check_alignment_get_addr(obj, index, 4)) = value->get_jint();
1341 break;
1342 case 8:
1343 *((jlong *) check_alignment_get_addr(obj, index, 8)) = (jlong) value->get_intptr();
1344 break;
1345 default:
1346 ShouldNotReachHere();
1347 }
1348 }
1349 #endif // INCLUDE_JVMCI
1350
1351
1352 // restore elements of an eliminated type array
1353 void Deoptimization::reassign_type_array_elements(frame* fr, RegisterMap* reg_map, ObjectValue* sv, typeArrayOop obj, BasicType type) {
1354 int index = 0;
1355
1356 for (int i = 0; i < sv->field_size(); i++) {
1357 StackValue* value = StackValue::create_stack_value(fr, reg_map, sv->field_at(i));
1358 switch(type) {
1359 case T_LONG: case T_DOUBLE: {
1360 assert(value->type() == T_INT, "Agreement.");
1361 StackValue* low =
1362 StackValue::create_stack_value(fr, reg_map, sv->field_at(++i));
1363 #ifdef _LP64
1364 jlong res = (jlong)low->get_intptr();
1365 #else
1366 jlong res = jlong_from(value->get_jint(), low->get_jint());
1367 #endif
1368 obj->long_at_put(index, res);
1369 break;
1370 }
1371
1372 case T_INT: case T_FLOAT: { // 4 bytes.
1373 assert(value->type() == T_INT, "Agreement.");
1374 bool big_value = false;
1375 if (i + 1 < sv->field_size() && type == T_INT) {
1376 if (sv->field_at(i)->is_location()) {
1377 Location::Type type = ((LocationValue*) sv->field_at(i))->location().type();
1378 if (type == Location::dbl || type == Location::lng) {
1379 big_value = true;
1380 }
1381 } else if (sv->field_at(i)->is_constant_int()) {
1382 ScopeValue* next_scope_field = sv->field_at(i + 1);
1383 if (next_scope_field->is_constant_long() || next_scope_field->is_constant_double()) {
1384 big_value = true;
1385 }
1386 }
1387 }
1388
1389 if (big_value) {
1390 StackValue* low = StackValue::create_stack_value(fr, reg_map, sv->field_at(++i));
1391 #ifdef _LP64
1392 jlong res = (jlong)low->get_intptr();
1393 #else
1394 jlong res = jlong_from(value->get_jint(), low->get_jint());
1395 #endif
1396 obj->int_at_put(index, *(jint*)&res);
1397 obj->int_at_put(++index, *((jint*)&res + 1));
1398 } else {
1399 obj->int_at_put(index, value->get_jint());
1400 }
1401 break;
1402 }
1403
1404 case T_SHORT:
1405 assert(value->type() == T_INT, "Agreement.");
1406 obj->short_at_put(index, (jshort)value->get_jint());
1407 break;
1408
1409 case T_CHAR:
1410 assert(value->type() == T_INT, "Agreement.");
1411 obj->char_at_put(index, (jchar)value->get_jint());
1412 break;
1413
1414 case T_BYTE: {
1415 assert(value->type() == T_INT, "Agreement.");
1416 #if INCLUDE_JVMCI
1417 // The value we get is erased as a regular int. We will need to find its actual byte count 'by hand'.
1418 int byte_count = count_number_of_bytes_for_entry(sv, i);
1419 byte_array_put(obj, value, index, byte_count);
1420 // According to byte_count contract, the values from i + 1 to i + byte_count are illegal values. Skip.
1421 i += byte_count - 1; // Balance the loop counter.
1422 index += byte_count;
1423 // index has been updated so continue at top of loop
1424 continue;
1425 #else
1426 obj->byte_at_put(index, (jbyte)value->get_jint());
1427 break;
1428 #endif // INCLUDE_JVMCI
1429 }
1430
1431 case T_BOOLEAN: {
1432 assert(value->type() == T_INT, "Agreement.");
1433 obj->bool_at_put(index, (jboolean)value->get_jint());
1434 break;
1435 }
1436
1437 default:
1438 ShouldNotReachHere();
1439 }
1440 index++;
1441 }
1442 }
1443
1444 // restore fields of an eliminated object array
1445 void Deoptimization::reassign_object_array_elements(frame* fr, RegisterMap* reg_map, ObjectValue* sv, objArrayOop obj) {
1446 for (int i = 0; i < sv->field_size(); i++) {
1447 StackValue* value = StackValue::create_stack_value(fr, reg_map, sv->field_at(i));
1448 assert(value->type() == T_OBJECT, "object element expected");
1449 obj->obj_at_put(i, value->get_obj()());
1450 }
1451 }
1452
1453 class ReassignedField {
1454 public:
1455 int _offset;
1456 BasicType _type;
1457 public:
1458 ReassignedField() {
1459 _offset = 0;
1460 _type = T_ILLEGAL;
1461 }
1462 };
1463
1464 // Gets the fields of `klass` that are eliminated by escape analysis and need to be reassigned
1465 static GrowableArray<ReassignedField>* get_reassigned_fields(InstanceKlass* klass, GrowableArray<ReassignedField>* fields, bool is_jvmci) {
1466 InstanceKlass* super = klass->superklass();
1467 if (super != nullptr) {
1468 get_reassigned_fields(super, fields, is_jvmci);
1469 }
1470 for (AllFieldStream fs(klass); !fs.done(); fs.next()) {
1471 if (!fs.access_flags().is_static() && (is_jvmci || !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 return fields;
1479 }
1480
1481 // Restore fields of an eliminated instance object employing the same field order used by the compiler.
1482 static int reassign_fields_by_klass(InstanceKlass* klass, frame* fr, RegisterMap* reg_map, ObjectValue* sv, int svIndex, oop obj, bool is_jvmci) {
1483 GrowableArray<ReassignedField>* fields = get_reassigned_fields(klass, new GrowableArray<ReassignedField>(), is_jvmci);
1484 for (int i = 0; i < fields->length(); i++) {
1485 ScopeValue* scope_field = sv->field_at(svIndex);
1486 StackValue* value = StackValue::create_stack_value(fr, reg_map, scope_field);
1487 int offset = fields->at(i)._offset;
1488 BasicType type = fields->at(i)._type;
1489 switch (type) {
1490 case T_OBJECT: case T_ARRAY:
1491 assert(value->type() == T_OBJECT, "Agreement.");
1492 obj->obj_field_put(offset, value->get_obj()());
1493 break;
1494
1495 case T_INT: case T_FLOAT: { // 4 bytes.
1496 assert(value->type() == T_INT, "Agreement.");
1497 bool big_value = false;
1498 if (i+1 < fields->length() && fields->at(i+1)._type == T_INT) {
1499 if (scope_field->is_location()) {
1500 Location::Type type = ((LocationValue*) scope_field)->location().type();
1501 if (type == Location::dbl || type == Location::lng) {
1502 big_value = true;
1503 }
1504 }
1505 if (scope_field->is_constant_int()) {
1506 ScopeValue* next_scope_field = sv->field_at(svIndex + 1);
1507 if (next_scope_field->is_constant_long() || next_scope_field->is_constant_double()) {
1508 big_value = true;
1509 }
1510 }
1511 }
1512
1513 if (big_value) {
1514 i++;
1515 assert(i < fields->length(), "second T_INT field needed");
1516 assert(fields->at(i)._type == T_INT, "T_INT field needed");
1517 } else {
1518 obj->int_field_put(offset, value->get_jint());
1519 break;
1520 }
1521 }
1522 /* no break */
1523
1524 case T_LONG: case T_DOUBLE: {
1525 assert(value->type() == T_INT, "Agreement.");
1526 StackValue* low = StackValue::create_stack_value(fr, reg_map, sv->field_at(++svIndex));
1527 #ifdef _LP64
1528 jlong res = (jlong)low->get_intptr();
1529 #else
1530 jlong res = jlong_from(value->get_jint(), low->get_jint());
1531 #endif
1532 obj->long_field_put(offset, res);
1533 break;
1534 }
1535
1536 case T_SHORT:
1537 assert(value->type() == T_INT, "Agreement.");
1538 obj->short_field_put(offset, (jshort)value->get_jint());
1539 break;
1540
1541 case T_CHAR:
1542 assert(value->type() == T_INT, "Agreement.");
1543 obj->char_field_put(offset, (jchar)value->get_jint());
1544 break;
1545
1546 case T_BYTE:
1547 assert(value->type() == T_INT, "Agreement.");
1548 obj->byte_field_put(offset, (jbyte)value->get_jint());
1549 break;
1550
1551 case T_BOOLEAN:
1552 assert(value->type() == T_INT, "Agreement.");
1553 obj->bool_field_put(offset, (jboolean)value->get_jint());
1554 break;
1555
1556 default:
1557 ShouldNotReachHere();
1558 }
1559 svIndex++;
1560 }
1561 return svIndex;
1562 }
1563
1564 // restore fields of all eliminated objects and arrays
1565 void Deoptimization::reassign_fields(frame* fr, RegisterMap* reg_map, GrowableArray<ScopeValue*>* objects, bool realloc_failures, bool is_jvmci) {
1566 for (int i = 0; i < objects->length(); i++) {
1567 assert(objects->at(i)->is_object(), "invalid debug information");
1568 ObjectValue* sv = (ObjectValue*) objects->at(i);
1569 Klass* k = java_lang_Class::as_Klass(sv->klass()->as_ConstantOopReadValue()->value()());
1570 Handle obj = sv->value();
1571 assert(obj.not_null() || realloc_failures, "reallocation was missed");
1572 #ifndef PRODUCT
1573 if (PrintDeoptimizationDetails) {
1574 tty->print_cr("reassign fields for object of type %s!", k->name()->as_C_string());
1575 }
1576 #endif // !PRODUCT
1577
1578 if (obj.is_null()) {
1579 continue;
1580 }
1581
1582 #if INCLUDE_JVMCI
1583 // Don't reassign fields of boxes that came from a cache. Caches may be in CDS.
1584 if (sv->is_auto_box() && ((AutoBoxObjectValue*) sv)->is_cached()) {
1585 continue;
1586 }
1587 #endif // INCLUDE_JVMCI
1588 if (EnableVectorSupport && VectorSupport::is_vector(k)) {
1589 assert(sv->field_size() == 1, "%s not a vector", k->name()->as_C_string());
1590 ScopeValue* payload = sv->field_at(0);
1591 if (payload->is_location() &&
1592 payload->as_LocationValue()->location().type() == Location::vector) {
1593 #ifndef PRODUCT
1594 if (PrintDeoptimizationDetails) {
1595 tty->print_cr("skip field reassignment for this vector - it should be assigned already");
1596 if (Verbose) {
1597 Handle obj = sv->value();
1598 k->oop_print_on(obj(), tty);
1599 }
1600 }
1601 #endif // !PRODUCT
1602 continue; // Such vector's value was already restored in VectorSupport::allocate_vector().
1603 }
1604 // Else fall-through to do assignment for scalar-replaced boxed vector representation
1605 // which could be restored after vector object allocation.
1606 }
1607 if (k->is_instance_klass()) {
1608 InstanceKlass* ik = InstanceKlass::cast(k);
1609 reassign_fields_by_klass(ik, fr, reg_map, sv, 0, obj(), is_jvmci);
1610 } else if (k->is_typeArray_klass()) {
1611 TypeArrayKlass* ak = TypeArrayKlass::cast(k);
1612 reassign_type_array_elements(fr, reg_map, sv, (typeArrayOop) obj(), ak->element_type());
1613 } else if (k->is_objArray_klass()) {
1614 reassign_object_array_elements(fr, reg_map, sv, (objArrayOop) obj());
1615 }
1616 }
1617 // These objects may escape when we return to Interpreter after deoptimization.
1618 // We need barrier so that stores that initialize these objects can't be reordered
1619 // with subsequent stores that make these objects accessible by other threads.
1620 OrderAccess::storestore();
1621 }
1622
1623
1624 // relock objects for which synchronization was eliminated
1625 bool Deoptimization::relock_objects(JavaThread* thread, GrowableArray<MonitorInfo*>* monitors,
1626 JavaThread* deoptee_thread, frame& fr, int exec_mode, bool realloc_failures) {
1627 bool relocked_objects = false;
1628 for (int i = 0; i < monitors->length(); i++) {
1629 MonitorInfo* mon_info = monitors->at(i);
1630 if (mon_info->eliminated()) {
1631 assert(!mon_info->owner_is_scalar_replaced() || realloc_failures, "reallocation was missed");
1632 relocked_objects = true;
1633 if (!mon_info->owner_is_scalar_replaced()) {
1634 Handle obj(thread, mon_info->owner());
1635 markWord mark = obj->mark();
1636 if (exec_mode == Unpack_none) {
1637 if (LockingMode == LM_LEGACY && mark.has_locker() && fr.sp() > (intptr_t*)mark.locker()) {
1638 // With exec_mode == Unpack_none obj may be thread local and locked in
1639 // a callee frame. Make the lock in the callee a recursive lock and restore the displaced header.
1640 markWord dmw = mark.displaced_mark_helper();
1641 mark.locker()->set_displaced_header(markWord::encode((BasicLock*) nullptr));
1642 obj->set_mark(dmw);
1643 }
1644 if (mark.has_monitor()) {
1645 // defer relocking if the deoptee thread is currently waiting for obj
1646 ObjectMonitor* waiting_monitor = deoptee_thread->current_waiting_monitor();
1647 if (waiting_monitor != nullptr && waiting_monitor->object() == obj()) {
1648 assert(fr.is_deoptimized_frame(), "frame must be scheduled for deoptimization");
1649 if (LockingMode == LM_LEGACY) {
1650 mon_info->lock()->set_displaced_header(markWord::unused_mark());
1651 } else if (UseObjectMonitorTable) {
1652 mon_info->lock()->clear_object_monitor_cache();
1653 }
1654 #ifdef ASSERT
1655 else {
1656 assert(LockingMode == LM_MONITOR || !UseObjectMonitorTable, "must be");
1657 mon_info->lock()->set_bad_metadata_deopt();
1658 }
1659 #endif
1660 JvmtiDeferredUpdates::inc_relock_count_after_wait(deoptee_thread);
1661 continue;
1662 }
1663 }
1664 }
1665 BasicLock* lock = mon_info->lock();
1666 if (LockingMode == LM_LIGHTWEIGHT) {
1667 // We have lost information about the correct state of the lock stack.
1668 // Entering may create an invalid lock stack. Inflate the lock if it
1669 // was fast_locked to restore the valid lock stack.
1670 if (UseObjectMonitorTable) {
1671 // UseObjectMonitorTable expects the BasicLock cache to be either a
1672 // valid ObjectMonitor* or nullptr. Right now it is garbage, set it
1673 // to nullptr.
1674 lock->clear_object_monitor_cache();
1675 }
1676 ObjectSynchronizer::enter_for(obj, lock, deoptee_thread);
1677 if (deoptee_thread->lock_stack().contains(obj())) {
1678 LightweightSynchronizer::inflate_fast_locked_object(obj(), ObjectSynchronizer::InflateCause::inflate_cause_vm_internal,
1679 deoptee_thread, thread);
1680 }
1681 assert(mon_info->owner()->is_locked(), "object must be locked now");
1682 assert(obj->mark().has_monitor(), "must be");
1683 assert(!deoptee_thread->lock_stack().contains(obj()), "must be");
1684 assert(ObjectSynchronizer::read_monitor(thread, obj(), obj->mark())->has_owner(deoptee_thread), "must be");
1685 } else {
1686 ObjectSynchronizer::enter_for(obj, lock, deoptee_thread);
1687 assert(mon_info->owner()->is_locked(), "object must be locked now");
1688 }
1689 }
1690 }
1691 }
1692 return relocked_objects;
1693 }
1694 #endif // COMPILER2_OR_JVMCI
1695
1696 vframeArray* Deoptimization::create_vframeArray(JavaThread* thread, frame fr, RegisterMap *reg_map, GrowableArray<compiledVFrame*>* chunk, bool realloc_failures) {
1697 Events::log_deopt_message(thread, "DEOPT PACKING pc=" INTPTR_FORMAT " sp=" INTPTR_FORMAT, p2i(fr.pc()), p2i(fr.sp()));
1698
1699 // Register map for next frame (used for stack crawl). We capture
1700 // the state of the deopt'ing frame's caller. Thus if we need to
1701 // stuff a C2I adapter we can properly fill in the callee-save
1702 // register locations.
1703 frame caller = fr.sender(reg_map);
1704 int frame_size = pointer_delta_as_int(caller.sp(), fr.sp());
1705
1706 frame sender = caller;
1707
1708 // Since the Java thread being deoptimized will eventually adjust it's own stack,
1709 // the vframeArray containing the unpacking information is allocated in the C heap.
1710 // For Compiler1, the caller of the deoptimized frame is saved for use by unpack_frames().
1711 vframeArray* array = vframeArray::allocate(thread, frame_size, chunk, reg_map, sender, caller, fr, realloc_failures);
1712
1713 // Compare the vframeArray to the collected vframes
1714 assert(array->structural_compare(thread, chunk), "just checking");
1715
1716 if (TraceDeoptimization) {
1717 ResourceMark rm;
1718 stringStream st;
1719 st.print_cr("DEOPT PACKING thread=" INTPTR_FORMAT " vframeArray=" INTPTR_FORMAT, p2i(thread), p2i(array));
1720 st.print(" ");
1721 fr.print_on(&st);
1722 st.print_cr(" Virtual frames (innermost/newest first):");
1723 for (int index = 0; index < chunk->length(); index++) {
1724 compiledVFrame* vf = chunk->at(index);
1725 int bci = vf->raw_bci();
1726 const char* code_name;
1727 if (bci == SynchronizationEntryBCI) {
1728 code_name = "sync entry";
1729 } else {
1730 Bytecodes::Code code = vf->method()->code_at(bci);
1731 code_name = Bytecodes::name(code);
1732 }
1733
1734 st.print(" VFrame %d (" INTPTR_FORMAT ")", index, p2i(vf));
1735 st.print(" - %s", vf->method()->name_and_sig_as_C_string());
1736 st.print(" - %s", code_name);
1737 st.print_cr(" @ bci=%d ", bci);
1738 }
1739 tty->print_raw(st.freeze());
1740 tty->cr();
1741 }
1742
1743 return array;
1744 }
1745
1746 #if COMPILER2_OR_JVMCI
1747 void Deoptimization::pop_frames_failed_reallocs(JavaThread* thread, vframeArray* array) {
1748 // Reallocation of some scalar replaced objects failed. Record
1749 // that we need to pop all the interpreter frames for the
1750 // deoptimized compiled frame.
1751 assert(thread->frames_to_pop_failed_realloc() == 0, "missed frames to pop?");
1752 thread->set_frames_to_pop_failed_realloc(array->frames());
1753 // Unlock all monitors here otherwise the interpreter will see a
1754 // mix of locked and unlocked monitors (because of failed
1755 // reallocations of synchronized objects) and be confused.
1756 for (int i = 0; i < array->frames(); i++) {
1757 MonitorChunk* monitors = array->element(i)->monitors();
1758 if (monitors != nullptr) {
1759 // Unlock in reverse order starting from most nested monitor.
1760 for (int j = (monitors->number_of_monitors() - 1); j >= 0; j--) {
1761 BasicObjectLock* src = monitors->at(j);
1762 if (src->obj() != nullptr) {
1763 ObjectSynchronizer::exit(src->obj(), src->lock(), thread);
1764 }
1765 }
1766 array->element(i)->free_monitors();
1767 #ifdef ASSERT
1768 array->element(i)->set_removed_monitors();
1769 #endif
1770 }
1771 }
1772 }
1773 #endif
1774
1775 void Deoptimization::deoptimize_single_frame(JavaThread* thread, frame fr, Deoptimization::DeoptReason reason) {
1776 assert(fr.can_be_deoptimized(), "checking frame type");
1777
1778 nmethod* nm = fr.cb()->as_nmethod_or_null();
1779 assert(nm != nullptr, "only compiled methods can deopt");
1780 DeoptAction action = (nm->is_not_entrant() ? Action_make_not_entrant : Action_none);
1781 ScopeDesc* cur_sd = nm->scope_desc_at(fr.pc());
1782 Bytecodes::Code bc = (cur_sd->bci() == -1 ? Bytecodes::_nop // deopt on method entry
1783 : cur_sd->method()->java_code_at(cur_sd->bci()));
1784 gather_statistics(nm, reason, action, bc);
1785
1786 if (LogCompilation && xtty != nullptr) {
1787 ttyLocker ttyl;
1788 xtty->begin_head("deoptimized thread='%zu' reason='%s' pc='" INTPTR_FORMAT "'",(uintx)thread->osthread()->thread_id(), trap_reason_name(reason), p2i(fr.pc()));
1789 nm->log_identity(xtty);
1790 xtty->end_head();
1791 for (ScopeDesc* sd = nm->scope_desc_at(fr.pc()); ; sd = sd->sender()) {
1792 xtty->begin_elem("jvms bci='%d'", sd->bci());
1793 xtty->method(sd->method());
1794 xtty->end_elem();
1795 if (sd->is_top()) break;
1796 }
1797 xtty->tail("deoptimized");
1798 }
1799
1800 Continuation::notify_deopt(thread, fr.sp());
1801
1802 // Patch the compiled method so that when execution returns to it we will
1803 // deopt the execution state and return to the interpreter.
1804 fr.deoptimize(thread);
1805 }
1806
1807 void Deoptimization::deoptimize(JavaThread* thread, frame fr, DeoptReason reason) {
1808 // Deoptimize only if the frame comes from compile code.
1809 // Do not deoptimize the frame which is already patched
1810 // during the execution of the loops below.
1811 if (!fr.is_compiled_frame() || fr.is_deoptimized_frame()) {
1812 return;
1813 }
1814 ResourceMark rm;
1815 deoptimize_single_frame(thread, fr, reason);
1816 }
1817
1818 #if INCLUDE_JVMCI
1819 address Deoptimization::deoptimize_for_missing_exception_handler(nmethod* nm) {
1820 // there is no exception handler for this pc => deoptimize
1821 nm->make_not_entrant("missing exception handler");
1822
1823 // Use Deoptimization::deoptimize for all of its side-effects:
1824 // gathering traps statistics, logging...
1825 // it also patches the return pc but we do not care about that
1826 // since we return a continuation to the deopt_blob below.
1827 JavaThread* thread = JavaThread::current();
1828 RegisterMap reg_map(thread,
1829 RegisterMap::UpdateMap::skip,
1830 RegisterMap::ProcessFrames::include,
1831 RegisterMap::WalkContinuation::skip);
1832 frame runtime_frame = thread->last_frame();
1833 frame caller_frame = runtime_frame.sender(®_map);
1834 assert(caller_frame.cb()->as_nmethod_or_null() == nm, "expect top frame compiled method");
1835 vframe* vf = vframe::new_vframe(&caller_frame, ®_map, thread);
1836 compiledVFrame* cvf = compiledVFrame::cast(vf);
1837 ScopeDesc* imm_scope = cvf->scope();
1838 MethodData* imm_mdo = get_method_data(thread, methodHandle(thread, imm_scope->method()), true);
1839 if (imm_mdo != nullptr) {
1840 // Lock to read ProfileData, and ensure lock is not broken by a safepoint
1841 MutexLocker ml(imm_mdo->extra_data_lock(), Mutex::_no_safepoint_check_flag);
1842
1843 ProfileData* pdata = imm_mdo->allocate_bci_to_data(imm_scope->bci(), nullptr);
1844 if (pdata != nullptr && pdata->is_BitData()) {
1845 BitData* bit_data = (BitData*) pdata;
1846 bit_data->set_exception_seen();
1847 }
1848 }
1849
1850 Deoptimization::deoptimize(thread, caller_frame, Deoptimization::Reason_not_compiled_exception_handler);
1851
1852 MethodData* trap_mdo = get_method_data(thread, methodHandle(thread, nm->method()), true);
1853 if (trap_mdo != nullptr) {
1854 trap_mdo->inc_trap_count(Deoptimization::Reason_not_compiled_exception_handler);
1855 }
1856
1857 return SharedRuntime::deopt_blob()->unpack_with_exception_in_tls();
1858 }
1859 #endif
1860
1861 void Deoptimization::deoptimize_frame_internal(JavaThread* thread, intptr_t* id, DeoptReason reason) {
1862 assert(thread == Thread::current() ||
1863 thread->is_handshake_safe_for(Thread::current()) ||
1864 SafepointSynchronize::is_at_safepoint(),
1865 "can only deoptimize other thread at a safepoint/handshake");
1866 // Compute frame and register map based on thread and sp.
1867 RegisterMap reg_map(thread,
1868 RegisterMap::UpdateMap::skip,
1869 RegisterMap::ProcessFrames::include,
1870 RegisterMap::WalkContinuation::skip);
1871 frame fr = thread->last_frame();
1872 while (fr.id() != id) {
1873 fr = fr.sender(®_map);
1874 }
1875 deoptimize(thread, fr, reason);
1876 }
1877
1878
1879 void Deoptimization::deoptimize_frame(JavaThread* thread, intptr_t* id, DeoptReason reason) {
1880 Thread* current = Thread::current();
1881 if (thread == current || thread->is_handshake_safe_for(current)) {
1882 Deoptimization::deoptimize_frame_internal(thread, id, reason);
1883 } else {
1884 VM_DeoptimizeFrame deopt(thread, id, reason);
1885 VMThread::execute(&deopt);
1886 }
1887 }
1888
1889 void Deoptimization::deoptimize_frame(JavaThread* thread, intptr_t* id) {
1890 deoptimize_frame(thread, id, Reason_constraint);
1891 }
1892
1893 // JVMTI PopFrame support
1894 JRT_LEAF(void, Deoptimization::popframe_preserve_args(JavaThread* thread, int bytes_to_save, void* start_address))
1895 {
1896 assert(thread == JavaThread::current(), "pre-condition");
1897 thread->popframe_preserve_args(in_ByteSize(bytes_to_save), start_address);
1898 }
1899 JRT_END
1900
1901 MethodData*
1902 Deoptimization::get_method_data(JavaThread* thread, const methodHandle& m,
1903 bool create_if_missing) {
1904 JavaThread* THREAD = thread; // For exception macros.
1905 MethodData* mdo = m()->method_data();
1906 if (mdo == nullptr && create_if_missing && !HAS_PENDING_EXCEPTION) {
1907 // Build an MDO. Ignore errors like OutOfMemory;
1908 // that simply means we won't have an MDO to update.
1909 Method::build_profiling_method_data(m, THREAD);
1910 if (HAS_PENDING_EXCEPTION) {
1911 // Only metaspace OOM is expected. No Java code executed.
1912 assert((PENDING_EXCEPTION->is_a(vmClasses::OutOfMemoryError_klass())), "we expect only an OOM error here");
1913 CLEAR_PENDING_EXCEPTION;
1914 }
1915 mdo = m()->method_data();
1916 }
1917 return mdo;
1918 }
1919
1920 #if COMPILER2_OR_JVMCI
1921 void Deoptimization::load_class_by_index(const constantPoolHandle& constant_pool, int index, TRAPS) {
1922 // In case of an unresolved klass entry, load the class.
1923 // This path is exercised from case _ldc in Parse::do_one_bytecode,
1924 // and probably nowhere else.
1925 // Even that case would benefit from simply re-interpreting the
1926 // bytecode, without paying special attention to the class index.
1927 // So this whole "class index" feature should probably be removed.
1928
1929 if (constant_pool->tag_at(index).is_unresolved_klass()) {
1930 Klass* tk = constant_pool->klass_at(index, THREAD);
1931 if (HAS_PENDING_EXCEPTION) {
1932 // Exception happened during classloading. We ignore the exception here, since it
1933 // is going to be rethrown since the current activation is going to be deoptimized and
1934 // the interpreter will re-execute the bytecode.
1935 // Do not clear probable Async Exceptions.
1936 CLEAR_PENDING_NONASYNC_EXCEPTION;
1937 // Class loading called java code which may have caused a stack
1938 // overflow. If the exception was thrown right before the return
1939 // to the runtime the stack is no longer guarded. Reguard the
1940 // stack otherwise if we return to the uncommon trap blob and the
1941 // stack bang causes a stack overflow we crash.
1942 JavaThread* jt = THREAD;
1943 bool guard_pages_enabled = jt->stack_overflow_state()->reguard_stack_if_needed();
1944 assert(guard_pages_enabled, "stack banging in uncommon trap blob may cause crash");
1945 }
1946 return;
1947 }
1948
1949 assert(!constant_pool->tag_at(index).is_symbol(),
1950 "no symbolic names here, please");
1951 }
1952
1953 #if INCLUDE_JFR
1954
1955 class DeoptReasonSerializer : public JfrSerializer {
1956 public:
1957 void serialize(JfrCheckpointWriter& writer) {
1958 writer.write_count((u4)(Deoptimization::Reason_LIMIT + 1)); // + Reason::many (-1)
1959 for (int i = -1; i < Deoptimization::Reason_LIMIT; ++i) {
1960 writer.write_key((u8)i);
1961 writer.write(Deoptimization::trap_reason_name(i));
1962 }
1963 }
1964 };
1965
1966 class DeoptActionSerializer : public JfrSerializer {
1967 public:
1968 void serialize(JfrCheckpointWriter& writer) {
1969 static const u4 nof_actions = Deoptimization::Action_LIMIT;
1970 writer.write_count(nof_actions);
1971 for (u4 i = 0; i < Deoptimization::Action_LIMIT; ++i) {
1972 writer.write_key(i);
1973 writer.write(Deoptimization::trap_action_name((int)i));
1974 }
1975 }
1976 };
1977
1978 static void register_serializers() {
1979 static int critical_section = 0;
1980 if (1 == critical_section || Atomic::cmpxchg(&critical_section, 0, 1) == 1) {
1981 return;
1982 }
1983 JfrSerializer::register_serializer(TYPE_DEOPTIMIZATIONREASON, true, new DeoptReasonSerializer());
1984 JfrSerializer::register_serializer(TYPE_DEOPTIMIZATIONACTION, true, new DeoptActionSerializer());
1985 }
1986
1987 static void post_deoptimization_event(nmethod* nm,
1988 const Method* method,
1989 int trap_bci,
1990 int instruction,
1991 Deoptimization::DeoptReason reason,
1992 Deoptimization::DeoptAction action) {
1993 assert(nm != nullptr, "invariant");
1994 assert(method != nullptr, "invariant");
1995 if (EventDeoptimization::is_enabled()) {
1996 static bool serializers_registered = false;
1997 if (!serializers_registered) {
1998 register_serializers();
1999 serializers_registered = true;
2000 }
2001 EventDeoptimization event;
2002 event.set_compileId(nm->compile_id());
2003 event.set_compiler(nm->compiler_type());
2004 event.set_method(method);
2005 event.set_lineNumber(method->line_number_from_bci(trap_bci));
2006 event.set_bci(trap_bci);
2007 event.set_instruction(instruction);
2008 event.set_reason(reason);
2009 event.set_action(action);
2010 event.commit();
2011 }
2012 }
2013
2014 #endif // INCLUDE_JFR
2015
2016 static void log_deopt(nmethod* nm, Method* tm, intptr_t pc, frame& fr, int trap_bci,
2017 const char* reason_name, const char* reason_action) {
2018 LogTarget(Debug, deoptimization) lt;
2019 if (lt.is_enabled()) {
2020 LogStream ls(lt);
2021 bool is_osr = nm->is_osr_method();
2022 ls.print("cid=%4d %s%s level=%d",
2023 nm->compile_id(), (is_osr ? "osr" : " "), (nm->preloaded() ? "preload" : ""), nm->comp_level());
2024 ls.print(" %s", tm->name_and_sig_as_C_string());
2025 ls.print(" trap_bci=%d ", trap_bci);
2026 if (is_osr) {
2027 ls.print("osr_bci=%d ", nm->osr_entry_bci());
2028 }
2029 ls.print("%s ", reason_name);
2030 ls.print("%s ", reason_action);
2031 ls.print_cr("pc=" INTPTR_FORMAT " relative_pc=" INTPTR_FORMAT,
2032 pc, fr.pc() - nm->code_begin());
2033 }
2034 }
2035
2036 JRT_ENTRY_PROF(void, Deoptimization, uncommon_trap_inner, Deoptimization::uncommon_trap_inner(JavaThread* current, jint trap_request)) {
2037 HandleMark hm(current);
2038
2039 // uncommon_trap() is called at the beginning of the uncommon trap
2040 // handler. Note this fact before we start generating temporary frames
2041 // that can confuse an asynchronous stack walker. This counter is
2042 // decremented at the end of unpack_frames().
2043
2044 current->inc_in_deopt_handler();
2045
2046 #if INCLUDE_JVMCI
2047 // JVMCI might need to get an exception from the stack, which in turn requires the register map to be valid
2048 RegisterMap reg_map(current,
2049 RegisterMap::UpdateMap::include,
2050 RegisterMap::ProcessFrames::include,
2051 RegisterMap::WalkContinuation::skip);
2052 #else
2053 RegisterMap reg_map(current,
2054 RegisterMap::UpdateMap::skip,
2055 RegisterMap::ProcessFrames::include,
2056 RegisterMap::WalkContinuation::skip);
2057 #endif
2058 frame stub_frame = current->last_frame();
2059 frame fr = stub_frame.sender(®_map);
2060
2061 // Log a message
2062 Events::log_deopt_message(current, "Uncommon trap: trap_request=" INT32_FORMAT_X_0 " fr.pc=" INTPTR_FORMAT " relative=" INTPTR_FORMAT,
2063 trap_request, p2i(fr.pc()), fr.pc() - fr.cb()->code_begin());
2064
2065 {
2066 ResourceMark rm;
2067
2068 DeoptReason reason = trap_request_reason(trap_request);
2069 DeoptAction action = trap_request_action(trap_request);
2070 #if INCLUDE_JVMCI
2071 int debug_id = trap_request_debug_id(trap_request);
2072 #endif
2073 jint unloaded_class_index = trap_request_index(trap_request); // CP idx or -1
2074
2075 vframe* vf = vframe::new_vframe(&fr, ®_map, current);
2076 compiledVFrame* cvf = compiledVFrame::cast(vf);
2077
2078 nmethod* nm = cvf->code();
2079
2080 ScopeDesc* trap_scope = cvf->scope();
2081
2082 bool is_receiver_constraint_failure = COMPILER2_PRESENT(VerifyReceiverTypes &&) (reason == Deoptimization::Reason_receiver_constraint);
2083
2084 if (is_receiver_constraint_failure) {
2085 tty->print_cr(" bci=%d pc=" INTPTR_FORMAT ", relative_pc=" INTPTR_FORMAT ", method=%s" JVMCI_ONLY(", debug_id=%d"),
2086 trap_scope->bci(), p2i(fr.pc()), fr.pc() - nm->code_begin(), trap_scope->method()->name_and_sig_as_C_string()
2087 JVMCI_ONLY(COMMA debug_id));
2088 }
2089
2090 methodHandle trap_method(current, trap_scope->method());
2091 int trap_bci = trap_scope->bci();
2092 #if INCLUDE_JVMCI
2093 jlong speculation = current->pending_failed_speculation();
2094 if (nm->is_compiled_by_jvmci()) {
2095 nm->update_speculation(current);
2096 } else {
2097 assert(speculation == 0, "There should not be a speculation for methods compiled by non-JVMCI compilers");
2098 }
2099
2100 if (trap_bci == SynchronizationEntryBCI) {
2101 trap_bci = 0;
2102 current->set_pending_monitorenter(true);
2103 }
2104
2105 if (reason == Deoptimization::Reason_transfer_to_interpreter) {
2106 current->set_pending_transfer_to_interpreter(true);
2107 }
2108 #endif
2109
2110 Bytecodes::Code trap_bc = trap_method->java_code_at(trap_bci);
2111 // Record this event in the histogram.
2112 gather_statistics(nm, reason, action, trap_bc);
2113
2114 // Ensure that we can record deopt. history:
2115 bool create_if_missing = ProfileTraps;
2116
2117 methodHandle profiled_method;
2118 #if INCLUDE_JVMCI
2119 if (nm->is_compiled_by_jvmci()) {
2120 profiled_method = methodHandle(current, nm->method());
2121 } else {
2122 profiled_method = trap_method;
2123 }
2124 #else
2125 profiled_method = trap_method;
2126 #endif
2127
2128 MethodData* trap_mdo =
2129 get_method_data(current, profiled_method, create_if_missing);
2130
2131 { // Log Deoptimization event for JFR, UL and event system
2132 Method* tm = trap_method();
2133 const char* reason_name = trap_reason_name(reason);
2134 const char* reason_action = trap_action_name(action);
2135 intptr_t pc = p2i(fr.pc());
2136
2137 JFR_ONLY(post_deoptimization_event(nm, tm, trap_bci, trap_bc, reason, action);)
2138 log_deopt(nm, tm, pc, fr, trap_bci, reason_name, reason_action);
2139 Events::log_deopt_message(current, "Uncommon trap: reason=%s action=%s pc=" INTPTR_FORMAT " method=%s @ %d %s",
2140 reason_name, reason_action, pc,
2141 tm->name_and_sig_as_C_string(), trap_bci, nm->compiler_name());
2142 }
2143
2144 // Print a bunch of diagnostics, if requested.
2145 if (TraceDeoptimization || LogCompilation || is_receiver_constraint_failure) {
2146 ResourceMark rm;
2147
2148 // Lock to read ProfileData, and ensure lock is not broken by a safepoint
2149 // We must do this already now, since we cannot acquire this lock while
2150 // holding the tty lock (lock ordering by rank).
2151 MutexLocker ml(trap_mdo->extra_data_lock(), Mutex::_no_safepoint_check_flag);
2152
2153 ttyLocker ttyl;
2154
2155 char buf[100];
2156 if (xtty != nullptr) {
2157 xtty->begin_head("uncommon_trap thread='%zu' %s",
2158 os::current_thread_id(),
2159 format_trap_request(buf, sizeof(buf), trap_request));
2160 #if INCLUDE_JVMCI
2161 if (speculation != 0) {
2162 xtty->print(" speculation='" JLONG_FORMAT "'", speculation);
2163 }
2164 #endif
2165 nm->log_identity(xtty);
2166 }
2167 Symbol* class_name = nullptr;
2168 bool unresolved = false;
2169 if (unloaded_class_index >= 0) {
2170 constantPoolHandle constants (current, trap_method->constants());
2171 if (constants->tag_at(unloaded_class_index).is_unresolved_klass()) {
2172 class_name = constants->klass_name_at(unloaded_class_index);
2173 unresolved = true;
2174 if (xtty != nullptr)
2175 xtty->print(" unresolved='1'");
2176 } else if (constants->tag_at(unloaded_class_index).is_symbol()) {
2177 class_name = constants->symbol_at(unloaded_class_index);
2178 }
2179 if (xtty != nullptr)
2180 xtty->name(class_name);
2181 }
2182 if (xtty != nullptr && trap_mdo != nullptr && (int)reason < (int)MethodData::_trap_hist_limit) {
2183 // Dump the relevant MDO state.
2184 // This is the deopt count for the current reason, any previous
2185 // reasons or recompiles seen at this point.
2186 int dcnt = trap_mdo->trap_count(reason);
2187 if (dcnt != 0)
2188 xtty->print(" count='%d'", dcnt);
2189
2190 // We need to lock to read the ProfileData. But to keep the locks ordered, we need to
2191 // lock extra_data_lock before the tty lock.
2192 ProfileData* pdata = trap_mdo->bci_to_data(trap_bci);
2193 int dos = (pdata == nullptr)? 0: pdata->trap_state();
2194 if (dos != 0) {
2195 xtty->print(" state='%s'", format_trap_state(buf, sizeof(buf), dos));
2196 if (trap_state_is_recompiled(dos)) {
2197 int recnt2 = trap_mdo->overflow_recompile_count();
2198 if (recnt2 != 0)
2199 xtty->print(" recompiles2='%d'", recnt2);
2200 }
2201 }
2202 }
2203 if (xtty != nullptr) {
2204 xtty->stamp();
2205 xtty->end_head();
2206 }
2207 if (TraceDeoptimization) { // make noise on the tty
2208 stringStream st;
2209 st.print("UNCOMMON TRAP method=%s", trap_scope->method()->name_and_sig_as_C_string());
2210 st.print(" bci=%d pc=" INTPTR_FORMAT ", relative_pc=" INTPTR_FORMAT JVMCI_ONLY(", debug_id=%d"),
2211 trap_scope->bci(), p2i(fr.pc()), fr.pc() - nm->code_begin() JVMCI_ONLY(COMMA debug_id));
2212 st.print(" compiler=%s compile_id=%d", nm->compiler_name(), nm->compile_id());
2213 #if INCLUDE_JVMCI
2214 if (nm->is_compiled_by_jvmci()) {
2215 const char* installed_code_name = nm->jvmci_name();
2216 if (installed_code_name != nullptr) {
2217 st.print(" (JVMCI: installed code name=%s) ", installed_code_name);
2218 }
2219 }
2220 #endif
2221 st.print(" (@" INTPTR_FORMAT ") thread=%zu reason=%s action=%s unloaded_class_index=%d" JVMCI_ONLY(" debug_id=%d"),
2222 p2i(fr.pc()),
2223 os::current_thread_id(),
2224 trap_reason_name(reason),
2225 trap_action_name(action),
2226 unloaded_class_index
2227 #if INCLUDE_JVMCI
2228 , debug_id
2229 #endif
2230 );
2231 if (class_name != nullptr) {
2232 st.print(unresolved ? " unresolved class: " : " symbol: ");
2233 class_name->print_symbol_on(&st);
2234 }
2235 st.cr();
2236 tty->print_raw(st.freeze());
2237 }
2238 if (xtty != nullptr) {
2239 // Log the precise location of the trap.
2240 for (ScopeDesc* sd = trap_scope; ; sd = sd->sender()) {
2241 xtty->begin_elem("jvms bci='%d'", sd->bci());
2242 xtty->method(sd->method());
2243 xtty->end_elem();
2244 if (sd->is_top()) break;
2245 }
2246 xtty->tail("uncommon_trap");
2247 }
2248 }
2249 // (End diagnostic printout.)
2250
2251 if (is_receiver_constraint_failure) {
2252 fatal("missing receiver type check");
2253 }
2254
2255 // Load class if necessary
2256 if (unloaded_class_index >= 0) {
2257 constantPoolHandle constants(current, trap_method->constants());
2258 load_class_by_index(constants, unloaded_class_index, THREAD);
2259 }
2260
2261 // Flush the nmethod if necessary and desirable.
2262 //
2263 // We need to avoid situations where we are re-flushing the nmethod
2264 // because of a hot deoptimization site. Repeated flushes at the same
2265 // point need to be detected by the compiler and avoided. If the compiler
2266 // cannot avoid them (or has a bug and "refuses" to avoid them), this
2267 // module must take measures to avoid an infinite cycle of recompilation
2268 // and deoptimization. There are several such measures:
2269 //
2270 // 1. If a recompilation is ordered a second time at some site X
2271 // and for the same reason R, the action is adjusted to 'reinterpret',
2272 // to give the interpreter time to exercise the method more thoroughly.
2273 // If this happens, the method's overflow_recompile_count is incremented.
2274 //
2275 // 2. If the compiler fails to reduce the deoptimization rate, then
2276 // the method's overflow_recompile_count will begin to exceed the set
2277 // limit PerBytecodeRecompilationCutoff. If this happens, the action
2278 // is adjusted to 'make_not_compilable', and the method is abandoned
2279 // to the interpreter. This is a performance hit for hot methods,
2280 // but is better than a disastrous infinite cycle of recompilations.
2281 // (Actually, only the method containing the site X is abandoned.)
2282 //
2283 // 3. In parallel with the previous measures, if the total number of
2284 // recompilations of a method exceeds the much larger set limit
2285 // PerMethodRecompilationCutoff, the method is abandoned.
2286 // This should only happen if the method is very large and has
2287 // many "lukewarm" deoptimizations. The code which enforces this
2288 // limit is elsewhere (class nmethod, class Method).
2289 //
2290 // Note that the per-BCI 'is_recompiled' bit gives the compiler one chance
2291 // to recompile at each bytecode independently of the per-BCI cutoff.
2292 //
2293 // The decision to update code is up to the compiler, and is encoded
2294 // in the Action_xxx code. If the compiler requests Action_none
2295 // no trap state is changed, no compiled code is changed, and the
2296 // computation suffers along in the interpreter.
2297 //
2298 // The other action codes specify various tactics for decompilation
2299 // and recompilation. Action_maybe_recompile is the loosest, and
2300 // allows the compiled code to stay around until enough traps are seen,
2301 // and until the compiler gets around to recompiling the trapping method.
2302 //
2303 // The other actions cause immediate removal of the present code.
2304
2305 // Traps caused by injected profile shouldn't pollute trap counts.
2306 bool injected_profile_trap = trap_method->has_injected_profile() &&
2307 (reason == Reason_intrinsic || reason == Reason_unreached);
2308
2309 bool update_trap_state = (reason != Reason_tenured) && !injected_profile_trap;
2310 bool make_not_entrant = false;
2311 bool make_not_compilable = false;
2312 bool reprofile = false;
2313 switch (action) {
2314 case Action_none:
2315 // Keep the old code.
2316 update_trap_state = false;
2317 break;
2318 case Action_maybe_recompile:
2319 // Do not need to invalidate the present code, but we can
2320 // initiate another
2321 // Start compiler without (necessarily) invalidating the nmethod.
2322 // The system will tolerate the old code, but new code should be
2323 // generated when possible.
2324 break;
2325 case Action_reinterpret:
2326 // Go back into the interpreter for a while, and then consider
2327 // recompiling form scratch.
2328 make_not_entrant = true;
2329 // Reset invocation counter for outer most method.
2330 // This will allow the interpreter to exercise the bytecodes
2331 // for a while before recompiling.
2332 // By contrast, Action_make_not_entrant is immediate.
2333 //
2334 // Note that the compiler will track null_check, null_assert,
2335 // range_check, and class_check events and log them as if they
2336 // had been traps taken from compiled code. This will update
2337 // the MDO trap history so that the next compilation will
2338 // properly detect hot trap sites.
2339 reprofile = true;
2340 break;
2341 case Action_make_not_entrant:
2342 // Request immediate recompilation, and get rid of the old code.
2343 // Make them not entrant, so next time they are called they get
2344 // recompiled. Unloaded classes are loaded now so recompile before next
2345 // time they are called. Same for uninitialized. The interpreter will
2346 // link the missing class, if any.
2347 make_not_entrant = true;
2348 break;
2349 case Action_make_not_compilable:
2350 // Give up on compiling this method at all.
2351 make_not_entrant = true;
2352 make_not_compilable = true;
2353 break;
2354 default:
2355 ShouldNotReachHere();
2356 }
2357
2358 // Setting +ProfileTraps fixes the following, on all platforms:
2359 // The result is infinite heroic-opt-uncommon-trap/deopt/recompile cycles, since the
2360 // recompile relies on a MethodData* to record heroic opt failures.
2361
2362 // Whether the interpreter is producing MDO data or not, we also need
2363 // to use the MDO to detect hot deoptimization points and control
2364 // aggressive optimization.
2365 bool inc_recompile_count = false;
2366
2367 // Lock to read ProfileData, and ensure lock is not broken by a safepoint
2368 ConditionalMutexLocker ml((trap_mdo != nullptr) ? trap_mdo->extra_data_lock() : nullptr,
2369 (trap_mdo != nullptr),
2370 Mutex::_no_safepoint_check_flag);
2371 ProfileData* pdata = nullptr;
2372 if (ProfileTraps && CompilerConfig::is_c2_or_jvmci_compiler_enabled() && update_trap_state && trap_mdo != nullptr) {
2373 assert(trap_mdo == get_method_data(current, profiled_method, false), "sanity");
2374 uint this_trap_count = 0;
2375 bool maybe_prior_trap = false;
2376 bool maybe_prior_recompile = false;
2377
2378 pdata = query_update_method_data(trap_mdo, trap_bci, reason, true,
2379 #if INCLUDE_JVMCI
2380 nm->is_compiled_by_jvmci() && nm->is_osr_method(),
2381 #endif
2382 nm->method(),
2383 //outputs:
2384 this_trap_count,
2385 maybe_prior_trap,
2386 maybe_prior_recompile);
2387 // Because the interpreter also counts null, div0, range, and class
2388 // checks, these traps from compiled code are double-counted.
2389 // This is harmless; it just means that the PerXTrapLimit values
2390 // are in effect a little smaller than they look.
2391
2392 DeoptReason per_bc_reason = reason_recorded_per_bytecode_if_any(reason);
2393 if (per_bc_reason != Reason_none) {
2394 // Now take action based on the partially known per-BCI history.
2395 if (maybe_prior_trap
2396 && this_trap_count >= (uint)PerBytecodeTrapLimit) {
2397 // If there are too many traps at this BCI, force a recompile.
2398 // This will allow the compiler to see the limit overflow, and
2399 // take corrective action, if possible. The compiler generally
2400 // does not use the exact PerBytecodeTrapLimit value, but instead
2401 // changes its tactics if it sees any traps at all. This provides
2402 // a little hysteresis, delaying a recompile until a trap happens
2403 // several times.
2404 //
2405 // Actually, since there is only one bit of counter per BCI,
2406 // the possible per-BCI counts are {0,1,(per-method count)}.
2407 // This produces accurate results if in fact there is only
2408 // one hot trap site, but begins to get fuzzy if there are
2409 // many sites. For example, if there are ten sites each
2410 // trapping two or more times, they each get the blame for
2411 // all of their traps.
2412 make_not_entrant = true;
2413 }
2414
2415 // Detect repeated recompilation at the same BCI, and enforce a limit.
2416 if (make_not_entrant && maybe_prior_recompile) {
2417 // More than one recompile at this point.
2418 inc_recompile_count = maybe_prior_trap;
2419 }
2420 } else {
2421 // For reasons which are not recorded per-bytecode, we simply
2422 // force recompiles unconditionally.
2423 // (Note that PerMethodRecompilationCutoff is enforced elsewhere.)
2424 make_not_entrant = true;
2425 }
2426
2427 // Go back to the compiler if there are too many traps in this method.
2428 if (this_trap_count >= per_method_trap_limit(reason)) {
2429 // If there are too many traps in this method, force a recompile.
2430 // This will allow the compiler to see the limit overflow, and
2431 // take corrective action, if possible.
2432 // (This condition is an unlikely backstop only, because the
2433 // PerBytecodeTrapLimit is more likely to take effect first,
2434 // if it is applicable.)
2435 make_not_entrant = true;
2436 }
2437
2438 // Here's more hysteresis: If there has been a recompile at
2439 // this trap point already, run the method in the interpreter
2440 // for a while to exercise it more thoroughly.
2441 if (make_not_entrant && maybe_prior_recompile && maybe_prior_trap) {
2442 reprofile = true;
2443 }
2444 }
2445
2446 // Take requested actions on the method:
2447
2448 // Recompile
2449 if (make_not_entrant) {
2450 if (!nm->make_not_entrant("uncommon trap")) {
2451 return; // the call did not change nmethod's state
2452 }
2453
2454 if (pdata != nullptr) {
2455 // Record the recompilation event, if any.
2456 int tstate0 = pdata->trap_state();
2457 int tstate1 = trap_state_set_recompiled(tstate0, true);
2458 if (tstate1 != tstate0)
2459 pdata->set_trap_state(tstate1);
2460 }
2461
2462 // For code aging we count traps separately here, using make_not_entrant()
2463 // as a guard against simultaneous deopts in multiple threads.
2464 if (reason == Reason_tenured && trap_mdo != nullptr) {
2465 trap_mdo->inc_tenure_traps();
2466 }
2467 }
2468
2469 if (inc_recompile_count) {
2470 trap_mdo->inc_overflow_recompile_count();
2471 if ((uint)trap_mdo->overflow_recompile_count() >
2472 (uint)PerBytecodeRecompilationCutoff) {
2473 // Give up on the method containing the bad BCI.
2474 if (trap_method() == nm->method()) {
2475 make_not_compilable = true;
2476 } else {
2477 trap_method->set_not_compilable("overflow_recompile_count > PerBytecodeRecompilationCutoff", CompLevel_full_optimization);
2478 // But give grace to the enclosing nm->method().
2479 }
2480 }
2481 }
2482
2483 // Reprofile
2484 if (reprofile) {
2485 CompilationPolicy::reprofile(trap_scope, nm->is_osr_method());
2486 }
2487
2488 // Give up compiling
2489 if (make_not_compilable && !nm->method()->is_not_compilable(CompLevel_full_optimization)) {
2490 assert(make_not_entrant, "consistent");
2491 nm->method()->set_not_compilable("give up compiling", CompLevel_full_optimization);
2492 }
2493
2494 if (ProfileExceptionHandlers && trap_mdo != nullptr) {
2495 BitData* exception_handler_data = trap_mdo->exception_handler_bci_to_data_or_null(trap_bci);
2496 if (exception_handler_data != nullptr) {
2497 // uncommon trap at the start of an exception handler.
2498 // C2 generates these for un-entered exception handlers.
2499 // mark the handler as entered to avoid generating
2500 // another uncommon trap the next time the handler is compiled
2501 exception_handler_data->set_exception_handler_entered();
2502 }
2503 }
2504
2505 } // Free marked resources
2506
2507 }
2508 JRT_END
2509
2510 ProfileData*
2511 Deoptimization::query_update_method_data(MethodData* trap_mdo,
2512 int trap_bci,
2513 Deoptimization::DeoptReason reason,
2514 bool update_total_trap_count,
2515 #if INCLUDE_JVMCI
2516 bool is_osr,
2517 #endif
2518 Method* compiled_method,
2519 //outputs:
2520 uint& ret_this_trap_count,
2521 bool& ret_maybe_prior_trap,
2522 bool& ret_maybe_prior_recompile) {
2523 trap_mdo->check_extra_data_locked();
2524
2525 bool maybe_prior_trap = false;
2526 bool maybe_prior_recompile = false;
2527 uint this_trap_count = 0;
2528 if (update_total_trap_count) {
2529 uint idx = reason;
2530 #if INCLUDE_JVMCI
2531 if (is_osr) {
2532 // Upper half of history array used for traps in OSR compilations
2533 idx += Reason_TRAP_HISTORY_LENGTH;
2534 }
2535 #endif
2536 uint prior_trap_count = trap_mdo->trap_count(idx);
2537 this_trap_count = trap_mdo->inc_trap_count(idx);
2538
2539 // If the runtime cannot find a place to store trap history,
2540 // it is estimated based on the general condition of the method.
2541 // If the method has ever been recompiled, or has ever incurred
2542 // a trap with the present reason , then this BCI is assumed
2543 // (pessimistically) to be the culprit.
2544 maybe_prior_trap = (prior_trap_count != 0);
2545 maybe_prior_recompile = (trap_mdo->decompile_count() != 0);
2546 }
2547 ProfileData* pdata = nullptr;
2548
2549
2550 // For reasons which are recorded per bytecode, we check per-BCI data.
2551 DeoptReason per_bc_reason = reason_recorded_per_bytecode_if_any(reason);
2552 assert(per_bc_reason != Reason_none || update_total_trap_count, "must be");
2553 if (per_bc_reason != Reason_none) {
2554 // Find the profile data for this BCI. If there isn't one,
2555 // try to allocate one from the MDO's set of spares.
2556 // This will let us detect a repeated trap at this point.
2557 pdata = trap_mdo->allocate_bci_to_data(trap_bci, reason_is_speculate(reason) ? compiled_method : nullptr);
2558
2559 if (pdata != nullptr) {
2560 if (reason_is_speculate(reason) && !pdata->is_SpeculativeTrapData()) {
2561 if (LogCompilation && xtty != nullptr) {
2562 ttyLocker ttyl;
2563 // no more room for speculative traps in this MDO
2564 xtty->elem("speculative_traps_oom");
2565 }
2566 }
2567 // Query the trap state of this profile datum.
2568 int tstate0 = pdata->trap_state();
2569 if (!trap_state_has_reason(tstate0, per_bc_reason))
2570 maybe_prior_trap = false;
2571 if (!trap_state_is_recompiled(tstate0))
2572 maybe_prior_recompile = false;
2573
2574 // Update the trap state of this profile datum.
2575 int tstate1 = tstate0;
2576 // Record the reason.
2577 tstate1 = trap_state_add_reason(tstate1, per_bc_reason);
2578 // Store the updated state on the MDO, for next time.
2579 if (tstate1 != tstate0)
2580 pdata->set_trap_state(tstate1);
2581 } else {
2582 if (LogCompilation && xtty != nullptr) {
2583 ttyLocker ttyl;
2584 // Missing MDP? Leave a small complaint in the log.
2585 xtty->elem("missing_mdp bci='%d'", trap_bci);
2586 }
2587 }
2588 }
2589
2590 // Return results:
2591 ret_this_trap_count = this_trap_count;
2592 ret_maybe_prior_trap = maybe_prior_trap;
2593 ret_maybe_prior_recompile = maybe_prior_recompile;
2594 return pdata;
2595 }
2596
2597 void
2598 Deoptimization::update_method_data_from_interpreter(MethodData* trap_mdo, int trap_bci, int reason) {
2599 ResourceMark rm;
2600 // Ignored outputs:
2601 uint ignore_this_trap_count;
2602 bool ignore_maybe_prior_trap;
2603 bool ignore_maybe_prior_recompile;
2604 assert(!reason_is_speculate(reason), "reason speculate only used by compiler");
2605 // JVMCI uses the total counts to determine if deoptimizations are happening too frequently -> do not adjust total counts
2606 bool update_total_counts = true JVMCI_ONLY( && !UseJVMCICompiler);
2607
2608 // Lock to read ProfileData, and ensure lock is not broken by a safepoint
2609 MutexLocker ml(trap_mdo->extra_data_lock(), Mutex::_no_safepoint_check_flag);
2610
2611 query_update_method_data(trap_mdo, trap_bci,
2612 (DeoptReason)reason,
2613 update_total_counts,
2614 #if INCLUDE_JVMCI
2615 false,
2616 #endif
2617 nullptr,
2618 ignore_this_trap_count,
2619 ignore_maybe_prior_trap,
2620 ignore_maybe_prior_recompile);
2621 }
2622
2623 PROF_ENTRY(Deoptimization::UnrollBlock*, Deoptimization, uncommon_trap, Deoptimization::uncommon_trap(JavaThread* current, jint trap_request, jint exec_mode))
2624 // Enable WXWrite: current function is called from methods compiled by C2 directly
2625 MACOS_AARCH64_ONLY(ThreadWXEnable wx(WXWrite, current));
2626
2627 // Still in Java no safepoints
2628 {
2629 // This enters VM and may safepoint
2630 uncommon_trap_inner(current, trap_request);
2631 }
2632 HandleMark hm(current);
2633 return fetch_unroll_info_helper(current, exec_mode);
2634 PROF_END
2635
2636 // Local derived constants.
2637 // Further breakdown of DataLayout::trap_state, as promised by DataLayout.
2638 const int DS_REASON_MASK = ((uint)DataLayout::trap_mask) >> 1;
2639 const int DS_RECOMPILE_BIT = DataLayout::trap_mask - DS_REASON_MASK;
2640
2641 //---------------------------trap_state_reason---------------------------------
2642 Deoptimization::DeoptReason
2643 Deoptimization::trap_state_reason(int trap_state) {
2644 // This assert provides the link between the width of DataLayout::trap_bits
2645 // and the encoding of "recorded" reasons. It ensures there are enough
2646 // bits to store all needed reasons in the per-BCI MDO profile.
2647 assert(DS_REASON_MASK >= Reason_RECORDED_LIMIT, "enough bits");
2648 int recompile_bit = (trap_state & DS_RECOMPILE_BIT);
2649 trap_state -= recompile_bit;
2650 if (trap_state == DS_REASON_MASK) {
2651 return Reason_many;
2652 } else {
2653 assert((int)Reason_none == 0, "state=0 => Reason_none");
2654 return (DeoptReason)trap_state;
2655 }
2656 }
2657 //-------------------------trap_state_has_reason-------------------------------
2658 int Deoptimization::trap_state_has_reason(int trap_state, int reason) {
2659 assert(reason_is_recorded_per_bytecode((DeoptReason)reason), "valid reason");
2660 assert(DS_REASON_MASK >= Reason_RECORDED_LIMIT, "enough bits");
2661 int recompile_bit = (trap_state & DS_RECOMPILE_BIT);
2662 trap_state -= recompile_bit;
2663 if (trap_state == DS_REASON_MASK) {
2664 return -1; // true, unspecifically (bottom of state lattice)
2665 } else if (trap_state == reason) {
2666 return 1; // true, definitely
2667 } else if (trap_state == 0) {
2668 return 0; // false, definitely (top of state lattice)
2669 } else {
2670 return 0; // false, definitely
2671 }
2672 }
2673 //-------------------------trap_state_add_reason-------------------------------
2674 int Deoptimization::trap_state_add_reason(int trap_state, int reason) {
2675 assert(reason_is_recorded_per_bytecode((DeoptReason)reason) || reason == Reason_many, "valid reason");
2676 int recompile_bit = (trap_state & DS_RECOMPILE_BIT);
2677 trap_state -= recompile_bit;
2678 if (trap_state == DS_REASON_MASK) {
2679 return trap_state + recompile_bit; // already at state lattice bottom
2680 } else if (trap_state == reason) {
2681 return trap_state + recompile_bit; // the condition is already true
2682 } else if (trap_state == 0) {
2683 return reason + recompile_bit; // no condition has yet been true
2684 } else {
2685 return DS_REASON_MASK + recompile_bit; // fall to state lattice bottom
2686 }
2687 }
2688 //-----------------------trap_state_is_recompiled------------------------------
2689 bool Deoptimization::trap_state_is_recompiled(int trap_state) {
2690 return (trap_state & DS_RECOMPILE_BIT) != 0;
2691 }
2692 //-----------------------trap_state_set_recompiled-----------------------------
2693 int Deoptimization::trap_state_set_recompiled(int trap_state, bool z) {
2694 if (z) return trap_state | DS_RECOMPILE_BIT;
2695 else return trap_state & ~DS_RECOMPILE_BIT;
2696 }
2697 //---------------------------format_trap_state---------------------------------
2698 // This is used for debugging and diagnostics, including LogFile output.
2699 const char* Deoptimization::format_trap_state(char* buf, size_t buflen,
2700 int trap_state) {
2701 assert(buflen > 0, "sanity");
2702 DeoptReason reason = trap_state_reason(trap_state);
2703 bool recomp_flag = trap_state_is_recompiled(trap_state);
2704 // Re-encode the state from its decoded components.
2705 int decoded_state = 0;
2706 if (reason_is_recorded_per_bytecode(reason) || reason == Reason_many)
2707 decoded_state = trap_state_add_reason(decoded_state, reason);
2708 if (recomp_flag)
2709 decoded_state = trap_state_set_recompiled(decoded_state, recomp_flag);
2710 // If the state re-encodes properly, format it symbolically.
2711 // Because this routine is used for debugging and diagnostics,
2712 // be robust even if the state is a strange value.
2713 size_t len;
2714 if (decoded_state != trap_state) {
2715 // Random buggy state that doesn't decode??
2716 len = jio_snprintf(buf, buflen, "#%d", trap_state);
2717 } else {
2718 len = jio_snprintf(buf, buflen, "%s%s",
2719 trap_reason_name(reason),
2720 recomp_flag ? " recompiled" : "");
2721 }
2722 return buf;
2723 }
2724
2725
2726 //--------------------------------statics--------------------------------------
2727 const char* Deoptimization::_trap_reason_name[] = {
2728 // Note: Keep this in sync. with enum DeoptReason.
2729 "none",
2730 "null_check",
2731 "null_assert" JVMCI_ONLY("_or_unreached0"),
2732 "range_check",
2733 "class_check",
2734 "array_check",
2735 "intrinsic" JVMCI_ONLY("_or_type_checked_inlining"),
2736 "bimorphic" JVMCI_ONLY("_or_optimized_type_check"),
2737 "profile_predicate",
2738 "auto_vectorization_check",
2739 "unloaded",
2740 "uninitialized",
2741 "initialized",
2742 "unreached",
2743 "unhandled",
2744 "constraint",
2745 "div0_check",
2746 "age",
2747 "predicate",
2748 "loop_limit_check",
2749 "speculate_class_check",
2750 "speculate_null_check",
2751 "speculate_null_assert",
2752 "unstable_if",
2753 "unstable_fused_if",
2754 "receiver_constraint",
2755 #if INCLUDE_JVMCI
2756 "aliasing",
2757 "transfer_to_interpreter",
2758 "not_compiled_exception_handler",
2759 "unresolved",
2760 "jsr_mismatch",
2761 #endif
2762 "tenured"
2763 };
2764 const char* Deoptimization::_trap_action_name[] = {
2765 // Note: Keep this in sync. with enum DeoptAction.
2766 "none",
2767 "maybe_recompile",
2768 "reinterpret",
2769 "make_not_entrant",
2770 "make_not_compilable"
2771 };
2772
2773 const char* Deoptimization::trap_reason_name(int reason) {
2774 // Check that every reason has a name
2775 STATIC_ASSERT(sizeof(_trap_reason_name)/sizeof(const char*) == Reason_LIMIT);
2776
2777 if (reason == Reason_many) return "many";
2778 if ((uint)reason < Reason_LIMIT)
2779 return _trap_reason_name[reason];
2780 static char buf[20];
2781 os::snprintf_checked(buf, sizeof(buf), "reason%d", reason);
2782 return buf;
2783 }
2784 const char* Deoptimization::trap_action_name(int action) {
2785 // Check that every action has a name
2786 STATIC_ASSERT(sizeof(_trap_action_name)/sizeof(const char*) == Action_LIMIT);
2787
2788 if ((uint)action < Action_LIMIT)
2789 return _trap_action_name[action];
2790 static char buf[20];
2791 os::snprintf_checked(buf, sizeof(buf), "action%d", action);
2792 return buf;
2793 }
2794
2795 // This is used for debugging and diagnostics, including LogFile output.
2796 const char* Deoptimization::format_trap_request(char* buf, size_t buflen,
2797 int trap_request) {
2798 jint unloaded_class_index = trap_request_index(trap_request);
2799 const char* reason = trap_reason_name(trap_request_reason(trap_request));
2800 const char* action = trap_action_name(trap_request_action(trap_request));
2801 #if INCLUDE_JVMCI
2802 int debug_id = trap_request_debug_id(trap_request);
2803 #endif
2804 size_t len;
2805 if (unloaded_class_index < 0) {
2806 len = jio_snprintf(buf, buflen, "reason='%s' action='%s'" JVMCI_ONLY(" debug_id='%d'"),
2807 reason, action
2808 #if INCLUDE_JVMCI
2809 ,debug_id
2810 #endif
2811 );
2812 } else {
2813 len = jio_snprintf(buf, buflen, "reason='%s' action='%s' index='%d'" JVMCI_ONLY(" debug_id='%d'"),
2814 reason, action, unloaded_class_index
2815 #if INCLUDE_JVMCI
2816 ,debug_id
2817 #endif
2818 );
2819 }
2820 return buf;
2821 }
2822
2823 juint Deoptimization::_deoptimization_hist
2824 [1 + 4 + 5] // total + online + archived
2825 [Deoptimization::Reason_LIMIT]
2826 [1 + Deoptimization::Action_LIMIT]
2827 [Deoptimization::BC_CASE_LIMIT]
2828 = {0};
2829
2830 enum {
2831 LSB_BITS = 8,
2832 LSB_MASK = right_n_bits(LSB_BITS)
2833 };
2834
2835 static void update(juint* cases, Bytecodes::Code bc) {
2836 juint* bc_counter_addr = nullptr;
2837 juint bc_counter = 0;
2838 // Look for an unused counter, or an exact match to this BC.
2839 if (bc != Bytecodes::_illegal) {
2840 for (int bc_case = 0; bc_case < Deoptimization::BC_CASE_LIMIT; bc_case++) {
2841 juint* counter_addr = &cases[bc_case];
2842 juint counter = *counter_addr;
2843 if ((counter == 0 && bc_counter_addr == nullptr)
2844 || (Bytecodes::Code)(counter & LSB_MASK) == bc) {
2845 // this counter is either free or is already devoted to this BC
2846 bc_counter_addr = counter_addr;
2847 bc_counter = counter | bc;
2848 }
2849 }
2850 }
2851 if (bc_counter_addr == nullptr) {
2852 // Overflow, or no given bytecode.
2853 bc_counter_addr = &cases[Deoptimization::BC_CASE_LIMIT-1];
2854 bc_counter = (*bc_counter_addr & ~LSB_MASK); // clear LSB
2855 }
2856 *bc_counter_addr = bc_counter + (1 << LSB_BITS);
2857 }
2858
2859
2860 void Deoptimization::gather_statistics(nmethod* nm, DeoptReason reason, DeoptAction action,
2861 Bytecodes::Code bc) {
2862 assert(reason >= 0 && reason < Reason_LIMIT, "oob");
2863 assert(action >= 0 && action < Action_LIMIT, "oob");
2864 _deoptimization_hist[0][Reason_none][0][0] += 1; // total
2865 _deoptimization_hist[0][reason][0][0] += 1; // per-reason total
2866
2867 update(_deoptimization_hist[0][reason][1+action], bc);
2868
2869 uint lvl = nm->comp_level() + (nm->is_aot() ? 4 : 0) + (nm->preloaded() ? 1 : 0);
2870 _deoptimization_hist[lvl][Reason_none][0][0] += 1; // total
2871 _deoptimization_hist[lvl][reason][0][0] += 1; // per-reason total
2872 update(_deoptimization_hist[lvl][reason][1+action], bc);
2873 }
2874
2875 jint Deoptimization::total_deoptimization_count() {
2876 return _deoptimization_hist[0][Reason_none][0][0];
2877 }
2878
2879 // Get the deopt count for a specific reason and a specific action. If either
2880 // one of 'reason' or 'action' is null, the method returns the sum of all
2881 // deoptimizations with the specific 'action' or 'reason' respectively.
2882 // If both arguments are null, the method returns the total deopt count.
2883 jint Deoptimization::deoptimization_count(const char *reason_str, const char *action_str) {
2884 if (reason_str == nullptr && action_str == nullptr) {
2885 return total_deoptimization_count();
2886 }
2887 juint counter = 0;
2888 for (int reason = 0; reason < Reason_LIMIT; reason++) {
2889 if (reason_str == nullptr || !strcmp(reason_str, trap_reason_name(reason))) {
2890 for (int action = 0; action < Action_LIMIT; action++) {
2891 if (action_str == nullptr || !strcmp(action_str, trap_action_name(action))) {
2892 juint* cases = _deoptimization_hist[0][reason][1+action];
2893 for (int bc_case = 0; bc_case < BC_CASE_LIMIT; bc_case++) {
2894 counter += cases[bc_case] >> LSB_BITS;
2895 }
2896 }
2897 }
2898 }
2899 }
2900 return counter;
2901 }
2902
2903 void Deoptimization::print_statistics() {
2904 ttyLocker ttyl;
2905 if (xtty != nullptr) xtty->head("statistics type='deoptimization'");
2906 tty->print_cr("Deoptimization traps recorded:");
2907 print_statistics_on(tty);
2908 if (xtty != nullptr) xtty->tail("statistics");
2909 }
2910
2911 void Deoptimization::print_statistics_on(const char* title, int lvl, outputStream* st) {
2912 juint total = _deoptimization_hist[lvl][Reason_none][0][0];
2913 juint account = total;
2914 #define PRINT_STAT_LINE(name, r) \
2915 st->print_cr(" %d (%4.1f%%) %s", (int)(r), ((r) == total ? 100.0 : (((r) * 100.0) / total)), name);
2916 if (total > 0) {
2917 st->print(" %s: ", title);
2918 PRINT_STAT_LINE("total", total);
2919 // For each non-zero entry in the histogram, print the reason,
2920 // the action, and (if specifically known) the type of bytecode.
2921 for (int reason = 0; reason < Reason_LIMIT; reason++) {
2922 for (int action = 0; action < Action_LIMIT; action++) {
2923 juint* cases = Deoptimization::_deoptimization_hist[lvl][reason][1+action];
2924 for (int bc_case = 0; bc_case < BC_CASE_LIMIT; bc_case++) {
2925 juint counter = cases[bc_case];
2926 if (counter != 0) {
2927 Bytecodes::Code bc = (Bytecodes::Code)(counter & LSB_MASK);
2928 const char* bc_name = "other";
2929 if (bc_case == (BC_CASE_LIMIT-1) && bc == Bytecodes::_nop) {
2930 // overwritten
2931 } else if (Bytecodes::is_defined(bc)) {
2932 bc_name = Bytecodes::name(bc);
2933 }
2934 juint r = counter >> LSB_BITS;
2935 st->print_cr(" %-34s %16s %16s: " UINT32_FORMAT_W(5) " (%4.1f%%)",
2936 trap_reason_name(reason), trap_action_name(action), bc_name,
2937 r, (r * 100.0) / total);
2938 account -= r;
2939 }
2940 }
2941 }
2942 }
2943 if (account != 0) {
2944 PRINT_STAT_LINE("unaccounted", account);
2945 }
2946 #undef PRINT_STAT_LINE
2947 }
2948 }
2949
2950 void Deoptimization::print_statistics_on(outputStream* st) {
2951 // print_statistics_on("Total", 0, st);
2952 print_statistics_on("Tier1", 1, st);
2953 print_statistics_on("Tier2", 2, st);
2954 print_statistics_on("Tier3", 3, st);
2955 print_statistics_on("Tier4", 4, st);
2956
2957 print_statistics_on("AOT Code Tier1", 5, st);
2958 print_statistics_on("AOT Code Tier2", 6, st);
2959 print_statistics_on("AOT Code Tier4", 8, st);
2960 print_statistics_on("AOT Code Tier5 (preloaded)", 9, st);
2961 }
2962
2963 #define DO_COUNTERS(macro) \
2964 macro(Deoptimization, fetch_unroll_info) \
2965 macro(Deoptimization, unpack_frames) \
2966 macro(Deoptimization, uncommon_trap_inner) \
2967 macro(Deoptimization, uncommon_trap)
2968
2969 #define INIT_COUNTER(sub, name) \
2970 NEWPERFTICKCOUNTERS(_perf_##sub##_##name##_timer, SUN_RT, #sub "::" #name) \
2971 NEWPERFEVENTCOUNTER(_perf_##sub##_##name##_count, SUN_RT, #sub "::" #name "_count");
2972
2973 void Deoptimization::init_counters() {
2974 if (ProfileRuntimeCalls && UsePerfData) {
2975 EXCEPTION_MARK;
2976
2977 DO_COUNTERS(INIT_COUNTER)
2978
2979 if (HAS_PENDING_EXCEPTION) {
2980 vm_exit_during_initialization("jvm_perf_init failed unexpectedly");
2981 }
2982 }
2983 }
2984 #undef INIT_COUNTER
2985
2986 #define PRINT_COUNTER(sub, name) { \
2987 jlong count = _perf_##sub##_##name##_count->get_value(); \
2988 if (count > 0) { \
2989 st->print_cr(" %-50s = " JLONG_FORMAT_W(6) "us (elapsed) " JLONG_FORMAT_W(6) "us (thread) (" JLONG_FORMAT_W(5) " events)", #sub "::" #name, \
2990 _perf_##sub##_##name##_timer->elapsed_counter_value_us(), \
2991 _perf_##sub##_##name##_timer->thread_counter_value_us(), \
2992 count); \
2993 }}
2994
2995 void Deoptimization::print_counters_on(outputStream* st) {
2996 if (ProfileRuntimeCalls && UsePerfData) {
2997 DO_COUNTERS(PRINT_COUNTER)
2998 } else {
2999 st->print_cr(" Deoptimization: no info (%s is disabled)", (UsePerfData ? "ProfileRuntimeCalls" : "UsePerfData"));
3000 }
3001 }
3002
3003 #undef PRINT_COUNTER
3004 #undef DO_COUNTERS
3005
3006 #else // COMPILER2_OR_JVMCI
3007
3008
3009 // Stubs for C1 only system.
3010 bool Deoptimization::trap_state_is_recompiled(int trap_state) {
3011 return false;
3012 }
3013
3014 const char* Deoptimization::trap_reason_name(int reason) {
3015 return "unknown";
3016 }
3017
3018 jint Deoptimization::total_deoptimization_count() {
3019 return 0;
3020 }
3021
3022 jint Deoptimization::deoptimization_count(const char *reason_str, const char *action_str) {
3023 return 0;
3024 }
3025
3026 void Deoptimization::print_statistics() {
3027 // no output
3028 }
3029
3030 void
3031 Deoptimization::update_method_data_from_interpreter(MethodData* trap_mdo, int trap_bci, int reason) {
3032 // no update
3033 }
3034
3035 int Deoptimization::trap_state_has_reason(int trap_state, int reason) {
3036 return 0;
3037 }
3038
3039 void Deoptimization::gather_statistics(nmethod* nm, DeoptReason reason, DeoptAction action,
3040 Bytecodes::Code bc) {
3041 // no update
3042 }
3043
3044 const char* Deoptimization::format_trap_state(char* buf, size_t buflen,
3045 int trap_state) {
3046 jio_snprintf(buf, buflen, "#%d", trap_state);
3047 return buf;
3048 }
3049
3050 void Deoptimization::init_counters() {
3051 // nothing to do
3052 }
3053
3054 void Deoptimization::print_counters_on(outputStream* st) {
3055 // no output
3056 }
3057
3058 void Deoptimization::print_statistics_on(outputStream* st) {
3059 // no output
3060 }
3061
3062 #endif // COMPILER2_OR_JVMCI