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.inline.hpp"
39 #include "interpreter/bytecodeStream.hpp"
40 #include "interpreter/interpreter.hpp"
41 #include "interpreter/oopMapCache.hpp"
42 #include "jvm.h"
43 #include "logging/log.hpp"
44 #include "logging/logLevel.hpp"
45 #include "logging/logMessage.hpp"
46 #include "logging/logStream.hpp"
47 #include "memory/allocation.inline.hpp"
48 #include "memory/oopFactory.hpp"
49 #include "memory/resourceArea.hpp"
50 #include "memory/universe.hpp"
51 #include "oops/constantPool.hpp"
52 #include "oops/fieldStreams.inline.hpp"
53 #include "oops/flatArrayKlass.hpp"
54 #include "oops/flatArrayOop.hpp"
55 #include "oops/inlineKlass.inline.hpp"
56 #include "oops/method.hpp"
57 #include "oops/objArrayKlass.hpp"
58 #include "oops/objArrayOop.inline.hpp"
59 #include "oops/oop.inline.hpp"
60 #include "oops/typeArrayOop.inline.hpp"
61 #include "oops/verifyOopClosure.hpp"
62 #include "prims/jvmtiDeferredUpdates.hpp"
63 #include "prims/jvmtiExport.hpp"
64 #include "prims/jvmtiThreadState.hpp"
65 #include "prims/methodHandles.hpp"
66 #include "prims/vectorSupport.hpp"
67 #include "runtime/atomicAccess.hpp"
68 #include "runtime/basicLock.inline.hpp"
69 #include "runtime/continuation.hpp"
70 #include "runtime/continuationEntry.inline.hpp"
71 #include "runtime/deoptimization.hpp"
72 #include "runtime/escapeBarrier.hpp"
73 #include "runtime/fieldDescriptor.inline.hpp"
74 #include "runtime/frame.inline.hpp"
75 #include "runtime/handles.inline.hpp"
76 #include "runtime/interfaceSupport.inline.hpp"
77 #include "runtime/javaThread.hpp"
78 #include "runtime/jniHandles.inline.hpp"
79 #include "runtime/keepStackGCProcessed.hpp"
80 #include "runtime/lockStack.inline.hpp"
81 #include "runtime/objectMonitor.inline.hpp"
82 #include "runtime/osThread.hpp"
83 #include "runtime/safepointVerifiers.hpp"
84 #include "runtime/sharedRuntime.hpp"
85 #include "runtime/signature.hpp"
86 #include "runtime/stackFrameStream.inline.hpp"
87 #include "runtime/stackValue.hpp"
88 #include "runtime/stackWatermarkSet.hpp"
89 #include "runtime/stubRoutines.hpp"
90 #include "runtime/synchronizer.hpp"
91 #include "runtime/threadSMR.hpp"
92 #include "runtime/threadWXSetters.inline.hpp"
93 #include "runtime/vframe.hpp"
94 #include "runtime/vframe_hp.hpp"
95 #include "runtime/vframeArray.hpp"
96 #include "runtime/vmOperations.hpp"
97 #include "utilities/checkedCast.hpp"
98 #include "utilities/events.hpp"
99 #include "utilities/growableArray.hpp"
100 #include "utilities/macros.hpp"
101 #include "utilities/preserveException.hpp"
102 #include "utilities/xmlstream.hpp"
103 #if INCLUDE_JFR
104 #include "jfr/jfr.inline.hpp"
105 #include "jfr/jfrEvents.hpp"
106 #include "jfr/metadata/jfrSerializer.hpp"
107 #endif
108
109 uint64_t DeoptimizationScope::_committed_deopt_gen = 0;
110 uint64_t DeoptimizationScope::_active_deopt_gen = 1;
111 bool DeoptimizationScope::_committing_in_progress = false;
112
113 DeoptimizationScope::DeoptimizationScope() : _required_gen(0) {
114 DEBUG_ONLY(_deopted = false;)
115
116 MutexLocker ml(NMethodState_lock, Mutex::_no_safepoint_check_flag);
117 // If there is nothing to deopt _required_gen is the same as comitted.
118 _required_gen = DeoptimizationScope::_committed_deopt_gen;
119 }
120
121 DeoptimizationScope::~DeoptimizationScope() {
122 assert(_deopted, "Deopt not executed");
123 }
124
125 void DeoptimizationScope::mark(nmethod* nm, bool inc_recompile_counts) {
126 if (!nm->can_be_deoptimized()) {
127 return;
128 }
129
130 ConditionalMutexLocker ml(NMethodState_lock, !NMethodState_lock->owned_by_self(), Mutex::_no_safepoint_check_flag);
131
132 // If it's already marked but we still need it to be deopted.
133 if (nm->is_marked_for_deoptimization()) {
134 dependent(nm);
135 return;
136 }
137
138 nmethod::DeoptimizationStatus status =
139 inc_recompile_counts ? nmethod::deoptimize : nmethod::deoptimize_noupdate;
140 AtomicAccess::store(&nm->_deoptimization_status, status);
141
142 // Make sure active is not committed
143 assert(DeoptimizationScope::_committed_deopt_gen < DeoptimizationScope::_active_deopt_gen, "Must be");
144 assert(nm->_deoptimization_generation == 0, "Is already marked");
145
146 nm->_deoptimization_generation = DeoptimizationScope::_active_deopt_gen;
147 _required_gen = DeoptimizationScope::_active_deopt_gen;
148 }
149
150 void DeoptimizationScope::dependent(nmethod* nm) {
151 ConditionalMutexLocker ml(NMethodState_lock, !NMethodState_lock->owned_by_self(), Mutex::_no_safepoint_check_flag);
152
153 // A method marked by someone else may have a _required_gen lower than what we marked with.
154 // Therefore only store it if it's higher than _required_gen.
155 if (_required_gen < nm->_deoptimization_generation) {
156 _required_gen = nm->_deoptimization_generation;
157 }
158 }
159
160 void DeoptimizationScope::deoptimize_marked() {
161 assert(!_deopted, "Already deopted");
162
163 // We are not alive yet.
164 if (!Universe::is_fully_initialized()) {
165 DEBUG_ONLY(_deopted = true;)
166 return;
167 }
168
169 // Safepoints are a special case, handled here.
170 if (SafepointSynchronize::is_at_safepoint()) {
171 DeoptimizationScope::_committed_deopt_gen = DeoptimizationScope::_active_deopt_gen;
172 DeoptimizationScope::_active_deopt_gen++;
173 Deoptimization::deoptimize_all_marked();
174 DEBUG_ONLY(_deopted = true;)
175 return;
176 }
177
178 uint64_t comitting = 0;
179 bool wait = false;
180 while (true) {
181 {
182 ConditionalMutexLocker ml(NMethodState_lock, !NMethodState_lock->owned_by_self(), Mutex::_no_safepoint_check_flag);
183
184 // First we check if we or someone else already deopted the gen we want.
185 if (DeoptimizationScope::_committed_deopt_gen >= _required_gen) {
186 DEBUG_ONLY(_deopted = true;)
187 return;
188 }
189 if (!_committing_in_progress) {
190 // The version we are about to commit.
191 comitting = DeoptimizationScope::_active_deopt_gen;
192 // Make sure new marks use a higher gen.
193 DeoptimizationScope::_active_deopt_gen++;
194 _committing_in_progress = true;
195 wait = false;
196 } else {
197 // Another thread is handshaking and committing a gen.
198 wait = true;
199 }
200 }
201 if (wait) {
202 // Wait and let the concurrent handshake be performed.
203 ThreadBlockInVM tbivm(JavaThread::current());
204 os::naked_yield();
205 } else {
206 // Performs the handshake.
207 Deoptimization::deoptimize_all_marked(); // May safepoint and an additional deopt may have occurred.
208 DEBUG_ONLY(_deopted = true;)
209 {
210 ConditionalMutexLocker ml(NMethodState_lock, !NMethodState_lock->owned_by_self(), Mutex::_no_safepoint_check_flag);
211
212 // Make sure that committed doesn't go backwards.
213 // Should only happen if we did a deopt during a safepoint above.
214 if (DeoptimizationScope::_committed_deopt_gen < comitting) {
215 DeoptimizationScope::_committed_deopt_gen = comitting;
216 }
217 _committing_in_progress = false;
218
219 assert(DeoptimizationScope::_committed_deopt_gen >= _required_gen, "Must be");
220
221 return;
222 }
223 }
224 }
225 }
226
227 Deoptimization::UnrollBlock::UnrollBlock(int size_of_deoptimized_frame,
228 int caller_adjustment,
229 int caller_actual_parameters,
230 int number_of_frames,
231 intptr_t* frame_sizes,
232 address* frame_pcs,
233 BasicType return_type,
234 int exec_mode) {
235 _size_of_deoptimized_frame = size_of_deoptimized_frame;
236 _caller_adjustment = caller_adjustment;
237 _caller_actual_parameters = caller_actual_parameters;
238 _number_of_frames = number_of_frames;
239 _frame_sizes = frame_sizes;
240 _frame_pcs = frame_pcs;
241 _register_block = NEW_C_HEAP_ARRAY(intptr_t, RegisterMap::reg_count * 2, mtCompiler);
242 _return_type = return_type;
243 _initial_info = 0;
244 // PD (x86 only)
245 _counter_temp = 0;
246 _unpack_kind = exec_mode;
247 _sender_sp_temp = 0;
248
249 _total_frame_sizes = size_of_frames();
250 assert(exec_mode >= 0 && exec_mode < Unpack_LIMIT, "Unexpected exec_mode");
251 }
252
253 Deoptimization::UnrollBlock::~UnrollBlock() {
254 FREE_C_HEAP_ARRAY(intptr_t, _frame_sizes);
255 FREE_C_HEAP_ARRAY(intptr_t, _frame_pcs);
256 FREE_C_HEAP_ARRAY(intptr_t, _register_block);
257 }
258
259 int Deoptimization::UnrollBlock::size_of_frames() const {
260 // Account first for the adjustment of the initial frame
261 intptr_t result = _caller_adjustment;
262 for (int index = 0; index < number_of_frames(); index++) {
263 result += frame_sizes()[index];
264 }
265 return checked_cast<int>(result);
266 }
267
268 void Deoptimization::UnrollBlock::print() {
269 ResourceMark rm;
270 stringStream st;
271 st.print_cr("UnrollBlock");
272 st.print_cr(" size_of_deoptimized_frame = %d", _size_of_deoptimized_frame);
273 st.print( " frame_sizes: ");
274 for (int index = 0; index < number_of_frames(); index++) {
275 st.print("%zd ", frame_sizes()[index]);
276 }
277 st.cr();
278 tty->print_raw(st.freeze());
279 }
280
281 // In order to make fetch_unroll_info work properly with escape
282 // analysis, the method was changed from JRT_LEAF to JRT_BLOCK_ENTRY.
283 // The actual reallocation of previously eliminated objects occurs in realloc_objects,
284 // which is called from the method fetch_unroll_info_helper below.
285 JRT_BLOCK_ENTRY(Deoptimization::UnrollBlock*, Deoptimization::fetch_unroll_info(JavaThread* current, int exec_mode))
286 // fetch_unroll_info() is called at the beginning of the deoptimization
287 // handler. Note this fact before we start generating temporary frames
288 // that can confuse an asynchronous stack walker. This counter is
289 // decremented at the end of unpack_frames().
290 current->inc_in_deopt_handler();
291
292 if (exec_mode == Unpack_exception) {
293 // When we get here, a callee has thrown an exception into a deoptimized
294 // frame. That throw might have deferred stack watermark checking until
295 // after unwinding. So we deal with such deferred requests here.
296 StackWatermarkSet::after_unwind(current);
297 }
298
299 return fetch_unroll_info_helper(current, exec_mode);
300 JRT_END
301
302 #if COMPILER2_OR_JVMCI
303
304 static Klass* get_refined_array_klass(Klass* k, frame* fr, RegisterMap* map, ObjectValue* sv, TRAPS) {
305 // If it's an array, get the properties
306 if (k->is_array_klass() && !k->is_typeArray_klass()) {
307 assert(!k->is_refArray_klass() && !k->is_flatArray_klass(), "Unexpected refined klass");
308 nmethod* nm = fr->cb()->as_nmethod_or_null();
309 if (nm->is_compiled_by_c2()) {
310 assert(sv->has_properties(), "Property information is missing");
311 ArrayKlass::ArrayProperties props = static_cast<ArrayKlass::ArrayProperties>(StackValue::create_stack_value(fr, map, sv->properties())->get_jint());
312 k = ObjArrayKlass::cast(k)->klass_with_properties(props, THREAD);
313 } else {
314 // TODO Graal needs to be fixed. Just go with the default properties for now
315 k = ObjArrayKlass::cast(k)->klass_with_properties(ArrayKlass::ArrayProperties::DEFAULT, THREAD);
316 }
317 }
318 return k;
319 }
320
321 // print information about reallocated objects
322 static void print_objects(JavaThread* deoptee_thread, frame* deoptee, RegisterMap* map,
323 GrowableArray<ScopeValue*>* objects, bool realloc_failures, TRAPS) {
324 ResourceMark rm;
325 stringStream st; // change to logStream with logging
326 st.print_cr("REALLOC OBJECTS in thread " INTPTR_FORMAT, p2i(deoptee_thread));
327 fieldDescriptor fd;
328
329 for (int i = 0; i < objects->length(); i++) {
330 ObjectValue* sv = (ObjectValue*) objects->at(i);
331 Handle obj = sv->value();
332
333 if (obj.is_null()) {
334 st.print_cr(" nullptr");
335 continue;
336 }
337
338 Klass* k = java_lang_Class::as_Klass(sv->klass()->as_ConstantOopReadValue()->value()());
339 k = get_refined_array_klass(k, deoptee, map, sv, THREAD);
340
341 st.print(" object <" INTPTR_FORMAT "> of type ", p2i(sv->value()()));
342 k->print_value_on(&st);
343 st.print_cr(" allocated (%zu bytes)", obj->size() * HeapWordSize);
344
345 if (Verbose && k != nullptr) {
346 k->oop_print_on(obj(), &st);
347 }
348 }
349 tty->print_raw(st.freeze());
350 }
351
352 static bool rematerialize_objects(JavaThread* thread, int exec_mode, nmethod* compiled_method,
353 frame& deoptee, RegisterMap& map, GrowableArray<compiledVFrame*>* chunk,
354 bool& deoptimized_objects) {
355 bool realloc_failures = false;
356 assert (chunk->at(0)->scope() != nullptr,"expect only compiled java frames");
357
358 JavaThread* deoptee_thread = chunk->at(0)->thread();
359 assert(exec_mode == Deoptimization::Unpack_none || (deoptee_thread == thread),
360 "a frame can only be deoptimized by the owner thread");
361
362 GrowableArray<ScopeValue*>* objects = chunk->at(0)->scope()->objects_to_rematerialize(deoptee, map);
363
364 // The flag return_oop() indicates call sites which return oop
365 // in compiled code. Such sites include java method calls,
366 // runtime calls (for example, used to allocate new objects/arrays
367 // on slow code path) and any other calls generated in compiled code.
368 // It is not guaranteed that we can get such information here only
369 // by analyzing bytecode in deoptimized frames. This is why this flag
370 // is set during method compilation (see Compile::Process_OopMap_Node()).
371 // If the previous frame was popped or if we are dispatching an exception,
372 // we don't have an oop result.
373 ScopeDesc* scope = chunk->at(0)->scope();
374 bool save_oop_result = scope->return_oop() && !thread->popframe_forcing_deopt_reexecution() && (exec_mode == Deoptimization::Unpack_deopt);
375 // In case of the return of multiple values, we must take care
376 // of all oop return values.
377 GrowableArray<Handle> return_oops;
378 InlineKlass* vk = nullptr;
379 if (save_oop_result && scope->return_scalarized()) {
380 vk = InlineKlass::returned_inline_klass(map);
381 if (vk != nullptr) {
382 vk->save_oop_fields(map, return_oops);
383 save_oop_result = false;
384 }
385 }
386 if (save_oop_result) {
387 // Reallocation may trigger GC. If deoptimization happened on return from
388 // call which returns oop we need to save it since it is not in oopmap.
389 oop result = deoptee.saved_oop_result(&map);
390 assert(oopDesc::is_oop_or_null(result), "must be oop");
391 return_oops.push(Handle(thread, result));
392 assert(Universe::heap()->is_in_or_null(result), "must be heap pointer");
393 if (TraceDeoptimization) {
394 tty->print_cr("SAVED OOP RESULT " INTPTR_FORMAT " in thread " INTPTR_FORMAT, p2i(result), p2i(thread));
395 tty->cr();
396 }
397 }
398 if (objects != nullptr || vk != nullptr) {
399 if (exec_mode == Deoptimization::Unpack_none) {
400 assert(thread->thread_state() == _thread_in_vm, "assumption");
401 JavaThread* THREAD = thread; // For exception macros.
402 // Clear pending OOM if reallocation fails and return true indicating allocation failure
403 if (vk != nullptr) {
404 realloc_failures = Deoptimization::realloc_inline_type_result(vk, map, return_oops, CHECK_AND_CLEAR_(true));
405 }
406 if (objects != nullptr) {
407 realloc_failures = realloc_failures || Deoptimization::realloc_objects(thread, &deoptee, &map, objects, CHECK_AND_CLEAR_(true));
408 guarantee(compiled_method != nullptr, "deopt must be associated with an nmethod");
409 bool is_jvmci = compiled_method->is_compiled_by_jvmci();
410 Deoptimization::reassign_fields(&deoptee, &map, objects, realloc_failures, is_jvmci, CHECK_AND_CLEAR_(true));
411 }
412 deoptimized_objects = true;
413 } else {
414 JavaThread* current = thread; // For JRT_BLOCK
415 JRT_BLOCK
416 if (vk != nullptr) {
417 realloc_failures = Deoptimization::realloc_inline_type_result(vk, map, return_oops, THREAD);
418 }
419 if (objects != nullptr) {
420 realloc_failures = realloc_failures || Deoptimization::realloc_objects(thread, &deoptee, &map, objects, THREAD);
421 guarantee(compiled_method != nullptr, "deopt must be associated with an nmethod");
422 bool is_jvmci = compiled_method->is_compiled_by_jvmci();
423 Deoptimization::reassign_fields(&deoptee, &map, objects, realloc_failures, is_jvmci, THREAD);
424 }
425 JRT_END
426 }
427 if (TraceDeoptimization && objects != nullptr) {
428 print_objects(deoptee_thread, &deoptee, &map, objects, realloc_failures, thread);
429 }
430 }
431 if (save_oop_result || vk != nullptr) {
432 // Restore result.
433 assert(return_oops.length() == 1, "no inline type");
434 deoptee.set_saved_oop_result(&map, return_oops.pop()());
435 }
436 return realloc_failures;
437 }
438
439 static void restore_eliminated_locks(JavaThread* thread, GrowableArray<compiledVFrame*>* chunk, bool realloc_failures,
440 frame& deoptee, int exec_mode, bool& deoptimized_objects) {
441 JavaThread* deoptee_thread = chunk->at(0)->thread();
442 assert(!EscapeBarrier::objs_are_deoptimized(deoptee_thread, deoptee.id()), "must relock just once");
443 assert(thread == Thread::current(), "should be");
444 HandleMark hm(thread);
445 #ifndef PRODUCT
446 bool first = true;
447 #endif // !PRODUCT
448 // Start locking from outermost/oldest frame
449 for (int i = (chunk->length() - 1); i >= 0; i--) {
450 compiledVFrame* cvf = chunk->at(i);
451 assert (cvf->scope() != nullptr,"expect only compiled java frames");
452 GrowableArray<MonitorInfo*>* monitors = cvf->monitors();
453 if (monitors->is_nonempty()) {
454 bool relocked = Deoptimization::relock_objects(thread, monitors, deoptee_thread, deoptee,
455 exec_mode, realloc_failures);
456 deoptimized_objects = deoptimized_objects || relocked;
457 #ifndef PRODUCT
458 if (PrintDeoptimizationDetails) {
459 ResourceMark rm;
460 stringStream st;
461 for (int j = 0; j < monitors->length(); j++) {
462 MonitorInfo* mi = monitors->at(j);
463 if (mi->eliminated()) {
464 if (first) {
465 first = false;
466 st.print_cr("RELOCK OBJECTS in thread " INTPTR_FORMAT, p2i(thread));
467 }
468 if (exec_mode == Deoptimization::Unpack_none) {
469 ObjectMonitor* monitor = deoptee_thread->current_waiting_monitor();
470 if (monitor != nullptr && monitor->object() == mi->owner()) {
471 st.print_cr(" object <" INTPTR_FORMAT "> DEFERRED relocking after wait", p2i(mi->owner()));
472 continue;
473 }
474 }
475 if (mi->owner_is_scalar_replaced()) {
476 Klass* k = java_lang_Class::as_Klass(mi->owner_klass());
477 st.print_cr(" failed reallocation for klass %s", k->external_name());
478 } else {
479 st.print_cr(" object <" INTPTR_FORMAT "> locked", p2i(mi->owner()));
480 }
481 }
482 }
483 tty->print_raw(st.freeze());
484 }
485 #endif // !PRODUCT
486 }
487 }
488 }
489
490 // Deoptimize objects, that is reallocate and relock them, just before they escape through JVMTI.
491 // The given vframes cover one physical frame.
492 bool Deoptimization::deoptimize_objects_internal(JavaThread* thread, GrowableArray<compiledVFrame*>* chunk,
493 bool& realloc_failures) {
494 frame deoptee = chunk->at(0)->fr();
495 JavaThread* deoptee_thread = chunk->at(0)->thread();
496 nmethod* nm = deoptee.cb()->as_nmethod_or_null();
497 RegisterMap map(chunk->at(0)->register_map());
498 bool deoptimized_objects = false;
499
500 bool const jvmci_enabled = JVMCI_ONLY(EnableJVMCI) NOT_JVMCI(false);
501
502 // Reallocate the non-escaping objects and restore their fields.
503 if (jvmci_enabled COMPILER2_PRESENT(|| (DoEscapeAnalysis && EliminateAllocations)
504 || EliminateAutoBox || EnableVectorAggressiveReboxing)) {
505 realloc_failures = rematerialize_objects(thread, Unpack_none, nm, deoptee, map, chunk, deoptimized_objects);
506 }
507
508 // MonitorInfo structures used in eliminate_locks are not GC safe.
509 NoSafepointVerifier no_safepoint;
510
511 // Now relock objects if synchronization on them was eliminated.
512 if (jvmci_enabled COMPILER2_PRESENT(|| ((DoEscapeAnalysis || EliminateNestedLocks) && EliminateLocks))) {
513 restore_eliminated_locks(thread, chunk, realloc_failures, deoptee, Unpack_none, deoptimized_objects);
514 }
515 return deoptimized_objects;
516 }
517 #endif // COMPILER2_OR_JVMCI
518
519 // This is factored, since it is both called from a JRT_LEAF (deoptimization) and a JRT_ENTRY (uncommon_trap)
520 Deoptimization::UnrollBlock* Deoptimization::fetch_unroll_info_helper(JavaThread* current, int exec_mode) {
521 JFR_ONLY(Jfr::check_and_process_sample_request(current);)
522 // When we get here we are about to unwind the deoptee frame. In order to
523 // catch not yet safe to use frames, the following stack watermark barrier
524 // poll will make such frames safe to use.
525 StackWatermarkSet::before_unwind(current);
526
527 // Note: there is a safepoint safety issue here. No matter whether we enter
528 // via vanilla deopt or uncommon trap we MUST NOT stop at a safepoint once
529 // the vframeArray is created.
530 //
531
532 // Allocate our special deoptimization ResourceMark
533 DeoptResourceMark* dmark = new DeoptResourceMark(current);
534 assert(current->deopt_mark() == nullptr, "Pending deopt!");
535 current->set_deopt_mark(dmark);
536
537 frame stub_frame = current->last_frame(); // Makes stack walkable as side effect
538 RegisterMap map(current,
539 RegisterMap::UpdateMap::include,
540 RegisterMap::ProcessFrames::include,
541 RegisterMap::WalkContinuation::skip);
542 RegisterMap dummy_map(current,
543 RegisterMap::UpdateMap::skip,
544 RegisterMap::ProcessFrames::include,
545 RegisterMap::WalkContinuation::skip);
546 // Now get the deoptee with a valid map
547 frame deoptee = stub_frame.sender(&map);
548 if (exec_mode == Unpack_deopt) {
549 assert(deoptee.is_deoptimized_frame(), "frame is not marked for deoptimization");
550 }
551 // Set the deoptee nmethod
552 assert(current->deopt_compiled_method() == nullptr, "Pending deopt!");
553 nmethod* nm = deoptee.cb()->as_nmethod_or_null();
554 current->set_deopt_compiled_method(nm);
555
556 if (VerifyStack) {
557 current->validate_frame_layout();
558 }
559
560 // Create a growable array of VFrames where each VFrame represents an inlined
561 // Java frame. This storage is allocated with the usual system arena.
562 assert(deoptee.is_compiled_frame(), "Wrong frame type");
563 GrowableArray<compiledVFrame*>* chunk = new GrowableArray<compiledVFrame*>(10);
564 vframe* vf = vframe::new_vframe(&deoptee, &map, current);
565 while (!vf->is_top()) {
566 assert(vf->is_compiled_frame(), "Wrong frame type");
567 chunk->push(compiledVFrame::cast(vf));
568 vf = vf->sender();
569 }
570 assert(vf->is_compiled_frame(), "Wrong frame type");
571 chunk->push(compiledVFrame::cast(vf));
572
573 bool realloc_failures = false;
574
575 #if COMPILER2_OR_JVMCI
576 bool const jvmci_enabled = JVMCI_ONLY(EnableJVMCI) NOT_JVMCI(false);
577
578 // Reallocate the non-escaping objects and restore their fields. Then
579 // relock objects if synchronization on them was eliminated.
580 if (jvmci_enabled COMPILER2_PRESENT( || (DoEscapeAnalysis && EliminateAllocations)
581 || EliminateAutoBox || EnableVectorAggressiveReboxing )) {
582 bool unused;
583 realloc_failures = rematerialize_objects(current, exec_mode, nm, deoptee, map, chunk, unused);
584 }
585 #endif // COMPILER2_OR_JVMCI
586
587 // Ensure that no safepoint is taken after pointers have been stored
588 // in fields of rematerialized objects. If a safepoint occurs from here on
589 // out the java state residing in the vframeArray will be missed.
590 // Locks may be rebaised in a safepoint.
591 NoSafepointVerifier no_safepoint;
592
593 #if COMPILER2_OR_JVMCI
594 if ((jvmci_enabled COMPILER2_PRESENT( || ((DoEscapeAnalysis || EliminateNestedLocks) && EliminateLocks) ))
595 && !EscapeBarrier::objs_are_deoptimized(current, deoptee.id())) {
596 bool unused = false;
597 restore_eliminated_locks(current, chunk, realloc_failures, deoptee, exec_mode, unused);
598 }
599 #endif // COMPILER2_OR_JVMCI
600
601 ScopeDesc* trap_scope = chunk->at(0)->scope();
602 Handle exceptionObject;
603 if (trap_scope->rethrow_exception()) {
604 #ifndef PRODUCT
605 if (PrintDeoptimizationDetails) {
606 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());
607 }
608 #endif // !PRODUCT
609
610 GrowableArray<ScopeValue*>* expressions = trap_scope->expressions();
611 guarantee(expressions != nullptr && expressions->length() == 1, "should have only exception on stack");
612 guarantee(exec_mode != Unpack_exception, "rethrow_exception set with Unpack_exception");
613 ScopeValue* topOfStack = expressions->top();
614 exceptionObject = StackValue::create_stack_value(&deoptee, &map, topOfStack)->get_obj();
615 guarantee(exceptionObject() != nullptr, "exception oop can not be null");
616 }
617
618 vframeArray* array = create_vframeArray(current, deoptee, &map, chunk, realloc_failures);
619 #if COMPILER2_OR_JVMCI
620 if (realloc_failures) {
621 // This destroys all ScopedValue bindings.
622 current->clear_scopedValueBindings();
623 pop_frames_failed_reallocs(current, array);
624 }
625 #endif
626
627 assert(current->vframe_array_head() == nullptr, "Pending deopt!");
628 current->set_vframe_array_head(array);
629
630 // Now that the vframeArray has been created if we have any deferred local writes
631 // added by jvmti then we can free up that structure as the data is now in the
632 // vframeArray
633
634 JvmtiDeferredUpdates::delete_updates_for_frame(current, array->original().id());
635
636 // Compute the caller frame based on the sender sp of stub_frame and stored frame sizes info.
637 CodeBlob* cb = stub_frame.cb();
638 // Verify we have the right vframeArray
639 assert(cb->frame_size() >= 0, "Unexpected frame size");
640 intptr_t* unpack_sp = stub_frame.sp() + cb->frame_size();
641 assert(unpack_sp == deoptee.unextended_sp(), "must be");
642
643 #ifdef ASSERT
644 assert(cb->is_deoptimization_stub() ||
645 cb->is_uncommon_trap_stub() ||
646 strcmp("Stub<DeoptimizationStub.deoptimizationHandler>", cb->name()) == 0 ||
647 strcmp("Stub<UncommonTrapStub.uncommonTrapHandler>", cb->name()) == 0,
648 "unexpected code blob: %s", cb->name());
649 #endif
650
651 // This is a guarantee instead of an assert because if vframe doesn't match
652 // we will unpack the wrong deoptimized frame and wind up in strange places
653 // where it will be very difficult to figure out what went wrong. Better
654 // to die an early death here than some very obscure death later when the
655 // trail is cold.
656 guarantee(array->unextended_sp() == unpack_sp, "vframe_array_head must contain the vframeArray to unpack");
657
658 int number_of_frames = array->frames();
659
660 // Compute the vframes' sizes. Note that frame_sizes[] entries are ordered from outermost to innermost
661 // virtual activation, which is the reverse of the elements in the vframes array.
662 intptr_t* frame_sizes = NEW_C_HEAP_ARRAY(intptr_t, number_of_frames, mtCompiler);
663 // +1 because we always have an interpreter return address for the final slot.
664 address* frame_pcs = NEW_C_HEAP_ARRAY(address, number_of_frames + 1, mtCompiler);
665 int popframe_extra_args = 0;
666 // Create an interpreter return address for the stub to use as its return
667 // address so the skeletal frames are perfectly walkable
668 frame_pcs[number_of_frames] = Interpreter::deopt_entry(vtos, 0);
669
670 // PopFrame requires that the preserved incoming arguments from the recently-popped topmost
671 // activation be put back on the expression stack of the caller for reexecution
672 if (JvmtiExport::can_pop_frame() && current->popframe_forcing_deopt_reexecution()) {
673 popframe_extra_args = in_words(current->popframe_preserved_args_size_in_words());
674 }
675
676 // Find the current pc for sender of the deoptee. Since the sender may have been deoptimized
677 // itself since the deoptee vframeArray was created we must get a fresh value of the pc rather
678 // than simply use array->sender.pc(). This requires us to walk the current set of frames
679 //
680 frame deopt_sender = stub_frame.sender(&dummy_map); // First is the deoptee frame
681 deopt_sender = deopt_sender.sender(&dummy_map); // Now deoptee caller
682
683 // It's possible that the number of parameters at the call site is
684 // different than number of arguments in the callee when method
685 // handles are used. If the caller is interpreted get the real
686 // value so that the proper amount of space can be added to it's
687 // frame.
688 bool caller_was_method_handle = false;
689 if (deopt_sender.is_interpreted_frame()) {
690 methodHandle method(current, deopt_sender.interpreter_frame_method());
691 Bytecode_invoke cur(method, deopt_sender.interpreter_frame_bci());
692 if (cur.has_member_arg()) {
693 // This should cover all real-world cases. One exception is a pathological chain of
694 // MH.linkToXXX() linker calls, which only trusted code could do anyway. To handle that case, we
695 // would need to get the size from the resolved method entry. Another exception would
696 // be an invokedynamic with an adapter that is really a MethodHandle linker.
697 caller_was_method_handle = true;
698 }
699 }
700
701 //
702 // frame_sizes/frame_pcs[0] oldest frame (int or c2i)
703 // frame_sizes/frame_pcs[1] next oldest frame (int)
704 // frame_sizes/frame_pcs[n] youngest frame (int)
705 //
706 // Now a pc in frame_pcs is actually the return address to the frame's caller (a frame
707 // owns the space for the return address to it's caller). Confusing ain't it.
708 //
709 // The vframe array can address vframes with indices running from
710 // 0.._frames-1. Index 0 is the youngest frame and _frame - 1 is the oldest (root) frame.
711 // When we create the skeletal frames we need the oldest frame to be in the zero slot
712 // in the frame_sizes/frame_pcs so the assembly code can do a trivial walk.
713 // so things look a little strange in this loop.
714 //
715 int callee_parameters = 0;
716 int callee_locals = 0;
717 for (int index = 0; index < array->frames(); index++ ) {
718 // frame[number_of_frames - 1 ] = on_stack_size(youngest)
719 // frame[number_of_frames - 2 ] = on_stack_size(sender(youngest))
720 // frame[number_of_frames - 3 ] = on_stack_size(sender(sender(youngest)))
721 frame_sizes[number_of_frames - 1 - index] = BytesPerWord * array->element(index)->on_stack_size(callee_parameters,
722 callee_locals,
723 index == 0,
724 popframe_extra_args);
725 // This pc doesn't have to be perfect just good enough to identify the frame
726 // as interpreted so the skeleton frame will be walkable
727 // The correct pc will be set when the skeleton frame is completely filled out
728 // The final pc we store in the loop is wrong and will be overwritten below
729 frame_pcs[number_of_frames - 1 - index ] = Interpreter::deopt_entry(vtos, 0) - frame::pc_return_offset;
730
731 callee_parameters = array->element(index)->method()->size_of_parameters();
732 callee_locals = array->element(index)->method()->max_locals();
733 popframe_extra_args = 0;
734 }
735
736 // Compute whether the root vframe returns a float or double value.
737 BasicType return_type;
738 {
739 methodHandle method(current, array->element(0)->method());
740 Bytecode_invoke invoke = Bytecode_invoke_check(method, array->element(0)->bci());
741 return_type = invoke.is_valid() ? invoke.result_type() : T_ILLEGAL;
742 }
743
744 // Compute information for handling adapters and adjusting the frame size of the caller.
745 int caller_adjustment = 0;
746
747 // Compute the amount the oldest interpreter frame will have to adjust
748 // its caller's stack by. If the caller is a compiled frame then
749 // we pretend that the callee has no parameters so that the
750 // extension counts for the full amount of locals and not just
751 // locals-parms. This is because without a c2i adapter the parm
752 // area as created by the compiled frame will not be usable by
753 // the interpreter. (Depending on the calling convention there
754 // may not even be enough space).
755
756 // QQQ I'd rather see this pushed down into last_frame_adjust
757 // and have it take the sender (aka caller).
758
759 if (!deopt_sender.is_interpreted_frame() || caller_was_method_handle) {
760 caller_adjustment = last_frame_adjust(0, callee_locals);
761 } else if (callee_locals > callee_parameters) {
762 // The caller frame may need extending to accommodate
763 // non-parameter locals of the first unpacked interpreted frame.
764 // Compute that adjustment.
765 caller_adjustment = last_frame_adjust(callee_parameters, callee_locals);
766 }
767
768 // If the sender is deoptimized we must retrieve the address of the handler
769 // since the frame will "magically" show the original pc before the deopt
770 // and we'd undo the deopt.
771
772 frame_pcs[0] = Continuation::is_cont_barrier_frame(deoptee) ? StubRoutines::cont_returnBarrier() : deopt_sender.raw_pc();
773 if (Continuation::is_continuation_enterSpecial(deopt_sender)) {
774 ContinuationEntry::from_frame(deopt_sender)->set_argsize(0);
775 }
776
777 assert(CodeCache::find_blob(frame_pcs[0]) != nullptr, "bad pc");
778
779 #if INCLUDE_JVMCI
780 if (exceptionObject() != nullptr) {
781 current->set_exception_oop(exceptionObject());
782 exec_mode = Unpack_exception;
783 assert(array->element(0)->rethrow_exception(), "must be");
784 }
785 #endif
786
787 if (current->frames_to_pop_failed_realloc() > 0 && exec_mode != Unpack_uncommon_trap) {
788 assert(current->has_pending_exception(), "should have thrown OOME");
789 current->set_exception_oop(current->pending_exception());
790 current->clear_pending_exception();
791 exec_mode = Unpack_exception;
792 }
793
794 #if INCLUDE_JVMCI
795 if (current->frames_to_pop_failed_realloc() > 0) {
796 current->set_pending_monitorenter(false);
797 }
798 #endif
799
800 int caller_actual_parameters = -1; // value not used except for interpreted frames, see below
801 if (deopt_sender.is_interpreted_frame()) {
802 caller_actual_parameters = callee_parameters + (caller_was_method_handle ? 1 : 0);
803 }
804
805 UnrollBlock* info = new UnrollBlock(array->frame_size() * BytesPerWord,
806 caller_adjustment * BytesPerWord,
807 caller_actual_parameters,
808 number_of_frames,
809 frame_sizes,
810 frame_pcs,
811 return_type,
812 exec_mode);
813 // On some platforms, we need a way to pass some platform dependent
814 // information to the unpacking code so the skeletal frames come out
815 // correct (initial fp value, unextended sp, ...)
816 info->set_initial_info((intptr_t) array->sender().initial_deoptimization_info());
817
818 if (array->frames() > 1) {
819 if (VerifyStack && TraceDeoptimization) {
820 tty->print_cr("Deoptimizing method containing inlining");
821 }
822 }
823
824 array->set_unroll_block(info);
825 return info;
826 }
827
828 // Called to cleanup deoptimization data structures in normal case
829 // after unpacking to stack and when stack overflow error occurs
830 void Deoptimization::cleanup_deopt_info(JavaThread *thread,
831 vframeArray *array) {
832
833 // Get array if coming from exception
834 if (array == nullptr) {
835 array = thread->vframe_array_head();
836 }
837 thread->set_vframe_array_head(nullptr);
838
839 // Free the previous UnrollBlock
840 vframeArray* old_array = thread->vframe_array_last();
841 thread->set_vframe_array_last(array);
842
843 if (old_array != nullptr) {
844 UnrollBlock* old_info = old_array->unroll_block();
845 old_array->set_unroll_block(nullptr);
846 delete old_info;
847 delete old_array;
848 }
849
850 // Deallocate any resource creating in this routine and any ResourceObjs allocated
851 // inside the vframeArray (StackValueCollections)
852
853 delete thread->deopt_mark();
854 thread->set_deopt_mark(nullptr);
855 thread->set_deopt_compiled_method(nullptr);
856
857
858 if (JvmtiExport::can_pop_frame()) {
859 // Regardless of whether we entered this routine with the pending
860 // popframe condition bit set, we should always clear it now
861 thread->clear_popframe_condition();
862 }
863
864 // unpack_frames() is called at the end of the deoptimization handler
865 // and (in C2) at the end of the uncommon trap handler. Note this fact
866 // so that an asynchronous stack walker can work again. This counter is
867 // incremented at the beginning of fetch_unroll_info() and (in C2) at
868 // the beginning of uncommon_trap().
869 thread->dec_in_deopt_handler();
870 }
871
872 // Moved from cpu directories because none of the cpus has callee save values.
873 // If a cpu implements callee save values, move this to deoptimization_<cpu>.cpp.
874 void Deoptimization::unwind_callee_save_values(frame* f, vframeArray* vframe_array) {
875
876 // This code is sort of the equivalent of C2IAdapter::setup_stack_frame back in
877 // the days we had adapter frames. When we deoptimize a situation where a
878 // compiled caller calls a compiled caller will have registers it expects
879 // to survive the call to the callee. If we deoptimize the callee the only
880 // way we can restore these registers is to have the oldest interpreter
881 // frame that we create restore these values. That is what this routine
882 // will accomplish.
883
884 // At the moment we have modified c2 to not have any callee save registers
885 // so this problem does not exist and this routine is just a place holder.
886
887 assert(f->is_interpreted_frame(), "must be interpreted");
888 }
889
890 #ifndef PRODUCT
891 #ifdef ASSERT
892 // Return true if the execution after the provided bytecode continues at the
893 // next bytecode in the code. This is not the case for gotos, returns, and
894 // throws.
895 static bool falls_through(Bytecodes::Code bc) {
896 switch (bc) {
897 case Bytecodes::_goto:
898 case Bytecodes::_goto_w:
899 case Bytecodes::_athrow:
900 case Bytecodes::_areturn:
901 case Bytecodes::_dreturn:
902 case Bytecodes::_freturn:
903 case Bytecodes::_ireturn:
904 case Bytecodes::_lreturn:
905 case Bytecodes::_jsr:
906 case Bytecodes::_ret:
907 case Bytecodes::_return:
908 case Bytecodes::_lookupswitch:
909 case Bytecodes::_tableswitch:
910 return false;
911 default:
912 return true;
913 }
914 }
915 #endif
916 #endif
917
918 // Return BasicType of value being returned
919 JRT_LEAF(BasicType, Deoptimization::unpack_frames(JavaThread* thread, int exec_mode))
920 assert(thread == JavaThread::current(), "pre-condition");
921
922 // We are already active in the special DeoptResourceMark any ResourceObj's we
923 // allocate will be freed at the end of the routine.
924
925 // JRT_LEAF methods don't normally allocate handles and there is a
926 // NoHandleMark to enforce that. It is actually safe to use Handles
927 // in a JRT_LEAF method, and sometimes desirable, but to do so we
928 // must use ResetNoHandleMark to bypass the NoHandleMark, and
929 // then use a HandleMark to ensure any Handles we do create are
930 // cleaned up in this scope.
931 ResetNoHandleMark rnhm;
932 HandleMark hm(thread);
933
934 frame stub_frame = thread->last_frame();
935
936 Continuation::notify_deopt(thread, stub_frame.sp());
937
938 // Since the frame to unpack is the top frame of this thread, the vframe_array_head
939 // must point to the vframeArray for the unpack frame.
940 vframeArray* array = thread->vframe_array_head();
941 UnrollBlock* info = array->unroll_block();
942
943 // We set the last_Java frame. But the stack isn't really parsable here. So we
944 // clear it to make sure JFR understands not to try and walk stacks from events
945 // in here.
946 intptr_t* sp = thread->frame_anchor()->last_Java_sp();
947 thread->frame_anchor()->set_last_Java_sp(nullptr);
948
949 // Unpack the interpreter frames and any adapter frame (c2 only) we might create.
950 array->unpack_to_stack(stub_frame, exec_mode, info->caller_actual_parameters());
951
952 thread->frame_anchor()->set_last_Java_sp(sp);
953
954 BasicType bt = info->return_type();
955
956 // If we have an exception pending, claim that the return type is an oop
957 // so the deopt_blob does not overwrite the exception_oop.
958
959 if (exec_mode == Unpack_exception)
960 bt = T_OBJECT;
961
962 // Cleanup thread deopt data
963 cleanup_deopt_info(thread, array);
964
965 #ifndef PRODUCT
966 if (VerifyStack) {
967 ResourceMark res_mark;
968 // Clear pending exception to not break verification code (restored afterwards)
969 PreserveExceptionMark pm(thread);
970
971 thread->validate_frame_layout();
972
973 // Verify that the just-unpacked frames match the interpreter's
974 // notions of expression stack and locals
975 vframeArray* cur_array = thread->vframe_array_last();
976 RegisterMap rm(thread,
977 RegisterMap::UpdateMap::skip,
978 RegisterMap::ProcessFrames::include,
979 RegisterMap::WalkContinuation::skip);
980 rm.set_include_argument_oops(false);
981 int callee_size_of_parameters = 0;
982 for (int frame_idx = 0; frame_idx < cur_array->frames(); frame_idx++) {
983 bool is_top_frame = (frame_idx == 0);
984 vframeArrayElement* el = cur_array->element(frame_idx);
985 frame* iframe = el->iframe();
986 guarantee(iframe->is_interpreted_frame(), "Wrong frame type");
987 methodHandle mh(thread, iframe->interpreter_frame_method());
988 bool reexecute = el->should_reexecute();
989
990 int cur_invoke_parameter_size = 0;
991 int top_frame_expression_stack_adjustment = 0;
992 int max_bci = mh->code_size();
993 BytecodeStream str(mh, iframe->interpreter_frame_bci());
994 assert(str.bci() < max_bci, "bci in interpreter frame out of bounds");
995 Bytecodes::Code cur_code = str.next();
996
997 if (!reexecute && !Bytecodes::is_invoke(cur_code)) {
998 // We can only compute OopMaps for the before state, so we need to roll forward
999 // to the next bytecode.
1000 assert(is_top_frame, "must be");
1001 assert(falls_through(cur_code), "must be");
1002 assert(cur_code != Bytecodes::_illegal, "illegal bytecode");
1003 assert(str.bci() < max_bci, "bci in interpreter frame out of bounds");
1004
1005 // Need to subtract off the size of the result type of
1006 // the bytecode because this is not described in the
1007 // debug info but returned to the interpreter in the TOS
1008 // caching register
1009 BasicType bytecode_result_type = Bytecodes::result_type(cur_code);
1010 if (bytecode_result_type != T_ILLEGAL) {
1011 top_frame_expression_stack_adjustment = type2size[bytecode_result_type];
1012 }
1013 assert(top_frame_expression_stack_adjustment >= 0, "stack adjustment must be positive");
1014
1015 cur_code = str.next();
1016 // Reflect the fact that we have rolled forward and now need
1017 // top_frame_expression_stack_adjustment
1018 reexecute = true;
1019 }
1020
1021 assert(cur_code != Bytecodes::_illegal, "illegal bytecode");
1022 assert(str.bci() < max_bci, "bci in interpreter frame out of bounds");
1023
1024 // Get the oop map for this bci
1025 InterpreterOopMap mask;
1026 OopMapCache::compute_one_oop_map(mh, str.bci(), &mask);
1027 // Check to see if we can grab the number of outgoing arguments
1028 // at an uncommon trap for an invoke (where the compiler
1029 // generates debug info before the invoke has executed)
1030 if (Bytecodes::is_invoke(cur_code)) {
1031 Bytecode_invoke invoke(mh, str.bci());
1032 cur_invoke_parameter_size = invoke.size_of_parameters();
1033 if (!is_top_frame && invoke.has_member_arg()) {
1034 callee_size_of_parameters++;
1035 }
1036 }
1037
1038 // Verify stack depth and oops in frame
1039 auto match = [&]() {
1040 int iframe_expr_ssize = iframe->interpreter_frame_expression_stack_size();
1041 #if INCLUDE_JVMCI
1042 if (is_top_frame && el->rethrow_exception()) {
1043 return iframe_expr_ssize == 1;
1044 }
1045 #endif
1046 // This should only be needed for C1
1047 if (is_top_frame && exec_mode == Unpack_exception && iframe_expr_ssize == 0) {
1048 return true;
1049 }
1050 if (reexecute) {
1051 int expr_ssize_before = iframe_expr_ssize + top_frame_expression_stack_adjustment;
1052 int oopmap_expr_invoke_ssize = mask.expression_stack_size() + cur_invoke_parameter_size;
1053 return expr_ssize_before == oopmap_expr_invoke_ssize;
1054 } else {
1055 int oopmap_expr_callee_ssize = mask.expression_stack_size() + callee_size_of_parameters;
1056 return iframe_expr_ssize == oopmap_expr_callee_ssize;
1057 }
1058 };
1059 if (!match()) {
1060 // Print out some information that will help us debug the problem
1061 tty->print_cr("Wrong number of expression stack elements during deoptimization");
1062 tty->print_cr(" Error occurred while verifying frame %d (0..%d, 0 is topmost)", frame_idx, cur_array->frames() - 1);
1063 tty->print_cr(" Current code %s", Bytecodes::name(cur_code));
1064 tty->print_cr(" Fabricated interpreter frame had %d expression stack elements",
1065 iframe->interpreter_frame_expression_stack_size());
1066 tty->print_cr(" Interpreter oop map had %d expression stack elements", mask.expression_stack_size());
1067 tty->print_cr(" callee_size_of_parameters = %d", callee_size_of_parameters);
1068 tty->print_cr(" top_frame_expression_stack_adjustment = %d", top_frame_expression_stack_adjustment);
1069 tty->print_cr(" exec_mode = %d", exec_mode);
1070 tty->print_cr(" original should_reexecute = %s", el->should_reexecute() ? "true" : "false");
1071 tty->print_cr(" reexecute = %s%s", reexecute ? "true" : "false",
1072 (reexecute != el->should_reexecute()) ? " (changed)" : "");
1073 #if INCLUDE_JVMCI
1074 tty->print_cr(" rethrow_exception = %s", el->rethrow_exception() ? "true" : "false");
1075 #endif
1076 tty->print_cr(" cur_invoke_parameter_size = %d", cur_invoke_parameter_size);
1077 tty->print_cr(" Thread = " INTPTR_FORMAT ", thread ID = %d", p2i(thread), thread->osthread()->thread_id());
1078 tty->print_cr(" Interpreted frames:");
1079 for (int k = 0; k < cur_array->frames(); k++) {
1080 vframeArrayElement* el = cur_array->element(k);
1081 tty->print_cr(" %s (bci %d)", el->method()->name_and_sig_as_C_string(), el->bci());
1082 }
1083 cur_array->print_on_2(tty);
1084 guarantee(false, "wrong number of expression stack elements during deopt");
1085 }
1086 VerifyOopClosure verify;
1087 iframe->oops_interpreted_do(&verify, &rm, false);
1088 callee_size_of_parameters = mh->size_of_parameters();
1089 }
1090 }
1091 #endif // !PRODUCT
1092
1093 return bt;
1094 JRT_END
1095
1096 class DeoptimizeMarkedHandshakeClosure : public HandshakeClosure {
1097 public:
1098 DeoptimizeMarkedHandshakeClosure() : HandshakeClosure("Deoptimize") {}
1099 void do_thread(Thread* thread) {
1100 JavaThread* jt = JavaThread::cast(thread);
1101 jt->deoptimize_marked_methods();
1102 }
1103 };
1104
1105 void Deoptimization::deoptimize_all_marked() {
1106 ResourceMark rm;
1107
1108 // Make the dependent methods not entrant
1109 CodeCache::make_marked_nmethods_deoptimized();
1110
1111 DeoptimizeMarkedHandshakeClosure deopt;
1112 if (SafepointSynchronize::is_at_safepoint()) {
1113 Threads::java_threads_do(&deopt);
1114 } else {
1115 Handshake::execute(&deopt);
1116 }
1117 }
1118
1119 Deoptimization::DeoptAction Deoptimization::_unloaded_action
1120 = Deoptimization::Action_reinterpret;
1121
1122 #if INCLUDE_JVMCI
1123 template<typename CacheType>
1124 class BoxCacheBase : public CHeapObj<mtCompiler> {
1125 protected:
1126 static InstanceKlass* find_cache_klass(Thread* thread, Symbol* klass_name) {
1127 ResourceMark rm(thread);
1128 char* klass_name_str = klass_name->as_C_string();
1129 InstanceKlass* ik = SystemDictionary::find_instance_klass(thread, klass_name, Handle());
1130 guarantee(ik != nullptr, "%s must be loaded", klass_name_str);
1131 if (!ik->is_in_error_state()) {
1132 guarantee(ik->is_initialized(), "%s must be initialized", klass_name_str);
1133 CacheType::compute_offsets(ik);
1134 }
1135 return ik;
1136 }
1137 };
1138
1139 template<typename PrimitiveType, typename CacheType, typename BoxType> class BoxCache : public BoxCacheBase<CacheType> {
1140 PrimitiveType _low;
1141 PrimitiveType _high;
1142 jobject _cache;
1143 protected:
1144 static BoxCache<PrimitiveType, CacheType, BoxType> *_singleton;
1145 BoxCache(Thread* thread) {
1146 InstanceKlass* ik = BoxCacheBase<CacheType>::find_cache_klass(thread, CacheType::symbol());
1147 if (ik->is_in_error_state()) {
1148 _low = 1;
1149 _high = 0;
1150 _cache = nullptr;
1151 } else {
1152 objArrayOop cache = CacheType::cache(ik);
1153 assert(cache->length() > 0, "Empty cache");
1154 _low = BoxType::value(cache->obj_at(0));
1155 _high = checked_cast<PrimitiveType>(_low + cache->length() - 1);
1156 _cache = JNIHandles::make_global(Handle(thread, cache));
1157 }
1158 }
1159 ~BoxCache() {
1160 JNIHandles::destroy_global(_cache);
1161 }
1162 public:
1163 static BoxCache<PrimitiveType, CacheType, BoxType>* singleton(Thread* thread) {
1164 if (_singleton == nullptr) {
1165 BoxCache<PrimitiveType, CacheType, BoxType>* s = new BoxCache<PrimitiveType, CacheType, BoxType>(thread);
1166 if (!AtomicAccess::replace_if_null(&_singleton, s)) {
1167 delete s;
1168 }
1169 }
1170 return _singleton;
1171 }
1172 oop lookup(PrimitiveType value) {
1173 if (_low <= value && value <= _high) {
1174 int offset = checked_cast<int>(value - _low);
1175 return objArrayOop(JNIHandles::resolve_non_null(_cache))->obj_at(offset);
1176 }
1177 return nullptr;
1178 }
1179 oop lookup_raw(intptr_t raw_value, bool& cache_init_error) {
1180 if (_cache == nullptr) {
1181 cache_init_error = true;
1182 return nullptr;
1183 }
1184 // Have to cast to avoid little/big-endian problems.
1185 if (sizeof(PrimitiveType) > sizeof(jint)) {
1186 jlong value = (jlong)raw_value;
1187 return lookup(value);
1188 }
1189 PrimitiveType value = (PrimitiveType)*((jint*)&raw_value);
1190 return lookup(value);
1191 }
1192 };
1193
1194 typedef BoxCache<jint, java_lang_Integer_IntegerCache, java_lang_Integer> IntegerBoxCache;
1195 typedef BoxCache<jlong, java_lang_Long_LongCache, java_lang_Long> LongBoxCache;
1196 typedef BoxCache<jchar, java_lang_Character_CharacterCache, java_lang_Character> CharacterBoxCache;
1197 typedef BoxCache<jshort, java_lang_Short_ShortCache, java_lang_Short> ShortBoxCache;
1198 typedef BoxCache<jbyte, java_lang_Byte_ByteCache, java_lang_Byte> ByteBoxCache;
1199
1200 template<> BoxCache<jint, java_lang_Integer_IntegerCache, java_lang_Integer>* BoxCache<jint, java_lang_Integer_IntegerCache, java_lang_Integer>::_singleton = nullptr;
1201 template<> BoxCache<jlong, java_lang_Long_LongCache, java_lang_Long>* BoxCache<jlong, java_lang_Long_LongCache, java_lang_Long>::_singleton = nullptr;
1202 template<> BoxCache<jchar, java_lang_Character_CharacterCache, java_lang_Character>* BoxCache<jchar, java_lang_Character_CharacterCache, java_lang_Character>::_singleton = nullptr;
1203 template<> BoxCache<jshort, java_lang_Short_ShortCache, java_lang_Short>* BoxCache<jshort, java_lang_Short_ShortCache, java_lang_Short>::_singleton = nullptr;
1204 template<> BoxCache<jbyte, java_lang_Byte_ByteCache, java_lang_Byte>* BoxCache<jbyte, java_lang_Byte_ByteCache, java_lang_Byte>::_singleton = nullptr;
1205
1206 class BooleanBoxCache : public BoxCacheBase<java_lang_Boolean> {
1207 jobject _true_cache;
1208 jobject _false_cache;
1209 protected:
1210 static BooleanBoxCache *_singleton;
1211 BooleanBoxCache(Thread *thread) {
1212 InstanceKlass* ik = find_cache_klass(thread, java_lang_Boolean::symbol());
1213 if (ik->is_in_error_state()) {
1214 _true_cache = nullptr;
1215 _false_cache = nullptr;
1216 } else {
1217 _true_cache = JNIHandles::make_global(Handle(thread, java_lang_Boolean::get_TRUE(ik)));
1218 _false_cache = JNIHandles::make_global(Handle(thread, java_lang_Boolean::get_FALSE(ik)));
1219 }
1220 }
1221 ~BooleanBoxCache() {
1222 JNIHandles::destroy_global(_true_cache);
1223 JNIHandles::destroy_global(_false_cache);
1224 }
1225 public:
1226 static BooleanBoxCache* singleton(Thread* thread) {
1227 if (_singleton == nullptr) {
1228 BooleanBoxCache* s = new BooleanBoxCache(thread);
1229 if (!AtomicAccess::replace_if_null(&_singleton, s)) {
1230 delete s;
1231 }
1232 }
1233 return _singleton;
1234 }
1235 oop lookup_raw(intptr_t raw_value, bool& cache_in_error) {
1236 if (_true_cache == nullptr) {
1237 cache_in_error = true;
1238 return nullptr;
1239 }
1240 // Have to cast to avoid little/big-endian problems.
1241 jboolean value = (jboolean)*((jint*)&raw_value);
1242 return lookup(value);
1243 }
1244 oop lookup(jboolean value) {
1245 if (value != 0) {
1246 return JNIHandles::resolve_non_null(_true_cache);
1247 }
1248 return JNIHandles::resolve_non_null(_false_cache);
1249 }
1250 };
1251
1252 BooleanBoxCache* BooleanBoxCache::_singleton = nullptr;
1253
1254 oop Deoptimization::get_cached_box(AutoBoxObjectValue* bv, frame* fr, RegisterMap* reg_map, bool& cache_init_error, TRAPS) {
1255 Klass* k = java_lang_Class::as_Klass(bv->klass()->as_ConstantOopReadValue()->value()());
1256 BasicType box_type = vmClasses::box_klass_type(k);
1257 if (box_type != T_OBJECT) {
1258 StackValue* value = StackValue::create_stack_value(fr, reg_map, bv->field_at(box_type == T_LONG ? 1 : 0));
1259 switch(box_type) {
1260 case T_INT: return IntegerBoxCache::singleton(THREAD)->lookup_raw(value->get_intptr(), cache_init_error);
1261 case T_CHAR: return CharacterBoxCache::singleton(THREAD)->lookup_raw(value->get_intptr(), cache_init_error);
1262 case T_SHORT: return ShortBoxCache::singleton(THREAD)->lookup_raw(value->get_intptr(), cache_init_error);
1263 case T_BYTE: return ByteBoxCache::singleton(THREAD)->lookup_raw(value->get_intptr(), cache_init_error);
1264 case T_BOOLEAN: return BooleanBoxCache::singleton(THREAD)->lookup_raw(value->get_intptr(), cache_init_error);
1265 case T_LONG: return LongBoxCache::singleton(THREAD)->lookup_raw(value->get_intptr(), cache_init_error);
1266 default:;
1267 }
1268 }
1269 return nullptr;
1270 }
1271 #endif // INCLUDE_JVMCI
1272
1273 #if COMPILER2_OR_JVMCI
1274 bool Deoptimization::realloc_objects(JavaThread* thread, frame* fr, RegisterMap* reg_map, GrowableArray<ScopeValue*>* objects, TRAPS) {
1275 Handle pending_exception(THREAD, thread->pending_exception());
1276 const char* exception_file = thread->exception_file();
1277 int exception_line = thread->exception_line();
1278 thread->clear_pending_exception();
1279
1280 bool failures = false;
1281
1282 for (int i = 0; i < objects->length(); i++) {
1283 assert(objects->at(i)->is_object(), "invalid debug information");
1284 ObjectValue* sv = (ObjectValue*) objects->at(i);
1285 Klass* k = java_lang_Class::as_Klass(sv->klass()->as_ConstantOopReadValue()->value()());
1286 k = get_refined_array_klass(k, fr, reg_map, sv, THREAD);
1287
1288 // Check if the object may be null and has an additional null_marker input that needs
1289 // to be checked before using the field values. Skip re-allocation if it is null.
1290 if (k->is_inline_klass() && sv->has_properties()) {
1291 jint null_marker = StackValue::create_stack_value(fr, reg_map, sv->properties())->get_jint();
1292 if (null_marker == 0) {
1293 continue;
1294 }
1295 }
1296
1297 oop obj = nullptr;
1298 bool cache_init_error = false;
1299 if (k->is_instance_klass()) {
1300 #if INCLUDE_JVMCI
1301 nmethod* nm = fr->cb()->as_nmethod_or_null();
1302 if (nm->is_compiled_by_jvmci() && sv->is_auto_box()) {
1303 AutoBoxObjectValue* abv = (AutoBoxObjectValue*) sv;
1304 obj = get_cached_box(abv, fr, reg_map, cache_init_error, THREAD);
1305 if (obj != nullptr) {
1306 // Set the flag to indicate the box came from a cache, so that we can skip the field reassignment for it.
1307 abv->set_cached(true);
1308 } else if (cache_init_error) {
1309 // Results in an OOME which is valid (as opposed to a class initialization error)
1310 // and is fine for the rare case a cache initialization failing.
1311 failures = true;
1312 }
1313 }
1314 #endif // INCLUDE_JVMCI
1315
1316 InstanceKlass* ik = InstanceKlass::cast(k);
1317 if (obj == nullptr && !cache_init_error) {
1318 InternalOOMEMark iom(THREAD);
1319 if (EnableVectorSupport && VectorSupport::is_vector(ik)) {
1320 obj = VectorSupport::allocate_vector(ik, fr, reg_map, sv, THREAD);
1321 } else {
1322 obj = ik->allocate_instance(THREAD);
1323 }
1324 }
1325 } else if (k->is_flatArray_klass()) {
1326 FlatArrayKlass* ak = FlatArrayKlass::cast(k);
1327 // Inline type array must be zeroed because not all memory is reassigned
1328 obj = ak->allocate_instance(sv->field_size(), ak->properties(), THREAD);
1329 } else if (k->is_typeArray_klass()) {
1330 TypeArrayKlass* ak = TypeArrayKlass::cast(k);
1331 assert(sv->field_size() % type2size[ak->element_type()] == 0, "non-integral array length");
1332 int len = sv->field_size() / type2size[ak->element_type()];
1333 InternalOOMEMark iom(THREAD);
1334 obj = ak->allocate_instance(len, THREAD);
1335 } else if (k->is_refArray_klass()) {
1336 RefArrayKlass* ak = RefArrayKlass::cast(k);
1337 InternalOOMEMark iom(THREAD);
1338 obj = ak->allocate_instance(sv->field_size(), ak->properties(), THREAD);
1339 }
1340
1341 if (obj == nullptr) {
1342 failures = true;
1343 }
1344
1345 assert(sv->value().is_null(), "redundant reallocation");
1346 assert(obj != nullptr || HAS_PENDING_EXCEPTION || cache_init_error, "allocation should succeed or we should get an exception");
1347 CLEAR_PENDING_EXCEPTION;
1348 sv->set_value(obj);
1349 }
1350
1351 if (failures) {
1352 THROW_OOP_(Universe::out_of_memory_error_realloc_objects(), failures);
1353 } else if (pending_exception.not_null()) {
1354 thread->set_pending_exception(pending_exception(), exception_file, exception_line);
1355 }
1356
1357 return failures;
1358 }
1359
1360 // We're deoptimizing at the return of a call, inline type fields are
1361 // in registers. When we go back to the interpreter, it will expect a
1362 // reference to an inline type instance. Allocate and initialize it from
1363 // the register values here.
1364 bool Deoptimization::realloc_inline_type_result(InlineKlass* vk, const RegisterMap& map, GrowableArray<Handle>& return_oops, TRAPS) {
1365 oop new_vt = vk->realloc_result(map, return_oops, THREAD);
1366 if (new_vt == nullptr) {
1367 CLEAR_PENDING_EXCEPTION;
1368 THROW_OOP_(Universe::out_of_memory_error_realloc_objects(), true);
1369 }
1370 return_oops.clear();
1371 return_oops.push(Handle(THREAD, new_vt));
1372 return false;
1373 }
1374
1375 #if INCLUDE_JVMCI
1376 /**
1377 * For primitive types whose kind gets "erased" at runtime (shorts become stack ints),
1378 * we need to somehow be able to recover the actual kind to be able to write the correct
1379 * amount of bytes.
1380 * For that purpose, this method assumes that, for an entry spanning n bytes at index i,
1381 * the entries at index n + 1 to n + i are 'markers'.
1382 * For example, if we were writing a short at index 4 of a byte array of size 8, the
1383 * expected form of the array would be:
1384 *
1385 * {b0, b1, b2, b3, INT, marker, b6, b7}
1386 *
1387 * Thus, in order to get back the size of the entry, we simply need to count the number
1388 * of marked entries
1389 *
1390 * @param virtualArray the virtualized byte array
1391 * @param i index of the virtual entry we are recovering
1392 * @return The number of bytes the entry spans
1393 */
1394 static int count_number_of_bytes_for_entry(ObjectValue *virtualArray, int i) {
1395 int index = i;
1396 while (++index < virtualArray->field_size() &&
1397 virtualArray->field_at(index)->is_marker()) {}
1398 return index - i;
1399 }
1400
1401 /**
1402 * If there was a guarantee for byte array to always start aligned to a long, we could
1403 * do a simple check on the parity of the index. Unfortunately, that is not always the
1404 * case. Thus, we check alignment of the actual address we are writing to.
1405 * In the unlikely case index 0 is 5-aligned for example, it would then be possible to
1406 * write a long to index 3.
1407 */
1408 static jbyte* check_alignment_get_addr(typeArrayOop obj, int index, int expected_alignment) {
1409 jbyte* res = obj->byte_at_addr(index);
1410 assert((((intptr_t) res) % expected_alignment) == 0, "Non-aligned write");
1411 return res;
1412 }
1413
1414 static void byte_array_put(typeArrayOop obj, StackValue* value, int index, int byte_count) {
1415 switch (byte_count) {
1416 case 1:
1417 obj->byte_at_put(index, (jbyte) value->get_jint());
1418 break;
1419 case 2:
1420 *((jshort *) check_alignment_get_addr(obj, index, 2)) = (jshort) value->get_jint();
1421 break;
1422 case 4:
1423 *((jint *) check_alignment_get_addr(obj, index, 4)) = value->get_jint();
1424 break;
1425 case 8:
1426 *((jlong *) check_alignment_get_addr(obj, index, 8)) = (jlong) value->get_intptr();
1427 break;
1428 default:
1429 ShouldNotReachHere();
1430 }
1431 }
1432 #endif // INCLUDE_JVMCI
1433
1434
1435 // restore elements of an eliminated type array
1436 void Deoptimization::reassign_type_array_elements(frame* fr, RegisterMap* reg_map, ObjectValue* sv, typeArrayOop obj, BasicType type) {
1437 int index = 0;
1438
1439 for (int i = 0; i < sv->field_size(); i++) {
1440 StackValue* value = StackValue::create_stack_value(fr, reg_map, sv->field_at(i));
1441 switch(type) {
1442 case T_LONG: case T_DOUBLE: {
1443 assert(value->type() == T_INT, "Agreement.");
1444 StackValue* low =
1445 StackValue::create_stack_value(fr, reg_map, sv->field_at(++i));
1446 #ifdef _LP64
1447 jlong res = (jlong)low->get_intptr();
1448 #else
1449 jlong res = jlong_from(value->get_jint(), low->get_jint());
1450 #endif
1451 obj->long_at_put(index, res);
1452 break;
1453 }
1454
1455 case T_INT: case T_FLOAT: { // 4 bytes.
1456 assert(value->type() == T_INT, "Agreement.");
1457 #if INCLUDE_JVMCI
1458 // big_value allows encoding double/long value as e.g. [int = 0, long], and storing
1459 // the value in two array elements.
1460 bool big_value = false;
1461 if (i + 1 < sv->field_size() && type == T_INT) {
1462 if (sv->field_at(i)->is_location()) {
1463 Location::Type type = ((LocationValue*) sv->field_at(i))->location().type();
1464 if (type == Location::dbl || type == Location::lng) {
1465 big_value = true;
1466 }
1467 } else if (sv->field_at(i)->is_constant_int()) {
1468 ScopeValue* next_scope_field = sv->field_at(i + 1);
1469 if (next_scope_field->is_constant_long() || next_scope_field->is_constant_double()) {
1470 big_value = true;
1471 }
1472 }
1473 }
1474
1475 if (big_value) {
1476 StackValue* low = StackValue::create_stack_value(fr, reg_map, sv->field_at(++i));
1477 #ifdef _LP64
1478 jlong res = (jlong)low->get_intptr();
1479 #else
1480 jlong res = jlong_from(value->get_jint(), low->get_jint());
1481 #endif
1482 obj->int_at_put(index, *(jint*)&res);
1483 obj->int_at_put(++index, *((jint*)&res + 1));
1484 } else {
1485 obj->int_at_put(index, value->get_jint());
1486 }
1487 #else // not INCLUDE_JVMCI
1488 obj->int_at_put(index, value->get_jint());
1489 #endif // INCLUDE_JVMCI
1490 break;
1491 }
1492
1493 case T_SHORT:
1494 assert(value->type() == T_INT, "Agreement.");
1495 obj->short_at_put(index, (jshort)value->get_jint());
1496 break;
1497
1498 case T_CHAR:
1499 assert(value->type() == T_INT, "Agreement.");
1500 obj->char_at_put(index, (jchar)value->get_jint());
1501 break;
1502
1503 case T_BYTE: {
1504 assert(value->type() == T_INT, "Agreement.");
1505 #if INCLUDE_JVMCI
1506 // The value we get is erased as a regular int. We will need to find its actual byte count 'by hand'.
1507 int byte_count = count_number_of_bytes_for_entry(sv, i);
1508 byte_array_put(obj, value, index, byte_count);
1509 // According to byte_count contract, the values from i + 1 to i + byte_count are illegal values. Skip.
1510 i += byte_count - 1; // Balance the loop counter.
1511 index += byte_count;
1512 // index has been updated so continue at top of loop
1513 continue;
1514 #else
1515 obj->byte_at_put(index, (jbyte)value->get_jint());
1516 break;
1517 #endif // INCLUDE_JVMCI
1518 }
1519
1520 case T_BOOLEAN: {
1521 assert(value->type() == T_INT, "Agreement.");
1522 obj->bool_at_put(index, (jboolean)value->get_jint());
1523 break;
1524 }
1525
1526 default:
1527 ShouldNotReachHere();
1528 }
1529 index++;
1530 }
1531 }
1532
1533 // restore fields of an eliminated object array
1534 void Deoptimization::reassign_object_array_elements(frame* fr, RegisterMap* reg_map, ObjectValue* sv, objArrayOop obj) {
1535 for (int i = 0; i < sv->field_size(); i++) {
1536 StackValue* value = StackValue::create_stack_value(fr, reg_map, sv->field_at(i));
1537 assert(value->type() == T_OBJECT, "object element expected");
1538 obj->obj_at_put(i, value->get_obj()());
1539 }
1540 }
1541
1542 class ReassignedField {
1543 public:
1544 int _offset;
1545 BasicType _type;
1546 InstanceKlass* _klass;
1547 bool _is_flat;
1548 bool _is_null_free;
1549 public:
1550 ReassignedField() : _offset(0), _type(T_ILLEGAL), _klass(nullptr), _is_flat(false), _is_null_free(false) { }
1551 };
1552
1553 // Gets the fields of `klass` that are eliminated by escape analysis and need to be reassigned
1554 static GrowableArray<ReassignedField>* get_reassigned_fields(InstanceKlass* klass, GrowableArray<ReassignedField>* fields, bool is_jvmci) {
1555 InstanceKlass* super = klass->super();
1556 if (super != nullptr) {
1557 get_reassigned_fields(super, fields, is_jvmci);
1558 }
1559 for (AllFieldStream fs(klass); !fs.done(); fs.next()) {
1560 if (!fs.access_flags().is_static() && (is_jvmci || !fs.field_flags().is_injected())) {
1561 ReassignedField field;
1562 field._offset = fs.offset();
1563 field._type = Signature::basic_type(fs.signature());
1564 if (fs.is_flat()) {
1565 field._is_flat = true;
1566 field._is_null_free = fs.is_null_free_inline_type();
1567 // Resolve klass of flat inline type field
1568 field._klass = InlineKlass::cast(klass->get_inline_type_field_klass(fs.index()));
1569 }
1570 fields->append(field);
1571 }
1572 }
1573 return fields;
1574 }
1575
1576 // Restore fields of an eliminated instance object employing the same field order used by the
1577 // compiler when it scalarizes an object at safepoints.
1578 static int reassign_fields_by_klass(InstanceKlass* klass, frame* fr, RegisterMap* reg_map, ObjectValue* sv, int svIndex, oop obj, bool is_jvmci, int base_offset, TRAPS) {
1579 GrowableArray<ReassignedField>* fields = get_reassigned_fields(klass, new GrowableArray<ReassignedField>(), is_jvmci);
1580 for (int i = 0; i < fields->length(); i++) {
1581 BasicType type = fields->at(i)._type;
1582 int offset = base_offset + fields->at(i)._offset;
1583 // Check for flat inline type field before accessing the ScopeValue because it might not have any fields
1584 if (fields->at(i)._is_flat) {
1585 // Recursively re-assign flat inline type fields
1586 InstanceKlass* vk = fields->at(i)._klass;
1587 assert(vk != nullptr, "must be resolved");
1588 offset -= InlineKlass::cast(vk)->payload_offset(); // Adjust offset to omit oop header
1589 svIndex = reassign_fields_by_klass(vk, fr, reg_map, sv, svIndex, obj, is_jvmci, offset, CHECK_0);
1590 if (!fields->at(i)._is_null_free) {
1591 ScopeValue* scope_field = sv->field_at(svIndex);
1592 StackValue* value = StackValue::create_stack_value(fr, reg_map, scope_field);
1593 int nm_offset = offset + InlineKlass::cast(vk)->null_marker_offset();
1594 obj->bool_field_put(nm_offset, value->get_jint() & 1);
1595 svIndex++;
1596 }
1597 continue; // Continue because we don't need to increment svIndex
1598 }
1599
1600 ScopeValue* scope_field = sv->field_at(svIndex);
1601 StackValue* value = StackValue::create_stack_value(fr, reg_map, scope_field);
1602 switch (type) {
1603 case T_OBJECT:
1604 case T_ARRAY:
1605 assert(value->type() == T_OBJECT, "Agreement.");
1606 obj->obj_field_put(offset, value->get_obj()());
1607 break;
1608
1609 case T_INT: case T_FLOAT: { // 4 bytes.
1610 assert(value->type() == T_INT, "Agreement.");
1611 bool big_value = false;
1612 if (i+1 < fields->length() && fields->at(i+1)._type == T_INT) {
1613 if (scope_field->is_location()) {
1614 Location::Type type = ((LocationValue*) scope_field)->location().type();
1615 if (type == Location::dbl || type == Location::lng) {
1616 big_value = true;
1617 }
1618 }
1619 if (scope_field->is_constant_int()) {
1620 ScopeValue* next_scope_field = sv->field_at(svIndex + 1);
1621 if (next_scope_field->is_constant_long() || next_scope_field->is_constant_double()) {
1622 big_value = true;
1623 }
1624 }
1625 }
1626
1627 if (big_value) {
1628 i++;
1629 assert(i < fields->length(), "second T_INT field needed");
1630 assert(fields->at(i)._type == T_INT, "T_INT field needed");
1631 } else {
1632 obj->int_field_put(offset, value->get_jint());
1633 break;
1634 }
1635 }
1636 /* no break */
1637
1638 case T_LONG: case T_DOUBLE: {
1639 assert(value->type() == T_INT, "Agreement.");
1640 StackValue* low = StackValue::create_stack_value(fr, reg_map, sv->field_at(++svIndex));
1641 #ifdef _LP64
1642 jlong res = (jlong)low->get_intptr();
1643 #else
1644 jlong res = jlong_from(value->get_jint(), low->get_jint());
1645 #endif
1646 obj->long_field_put(offset, res);
1647 break;
1648 }
1649
1650 case T_SHORT:
1651 assert(value->type() == T_INT, "Agreement.");
1652 obj->short_field_put(offset, (jshort)value->get_jint());
1653 break;
1654
1655 case T_CHAR:
1656 assert(value->type() == T_INT, "Agreement.");
1657 obj->char_field_put(offset, (jchar)value->get_jint());
1658 break;
1659
1660 case T_BYTE:
1661 assert(value->type() == T_INT, "Agreement.");
1662 obj->byte_field_put(offset, (jbyte)value->get_jint());
1663 break;
1664
1665 case T_BOOLEAN:
1666 assert(value->type() == T_INT, "Agreement.");
1667 obj->bool_field_put(offset, (jboolean)value->get_jint());
1668 break;
1669
1670 default:
1671 ShouldNotReachHere();
1672 }
1673 svIndex++;
1674 }
1675
1676 return svIndex;
1677 }
1678
1679 // restore fields of an eliminated inline type array
1680 void Deoptimization::reassign_flat_array_elements(frame* fr, RegisterMap* reg_map, ObjectValue* sv, flatArrayOop obj, FlatArrayKlass* vak, bool is_jvmci, TRAPS) {
1681 InlineKlass* vk = vak->element_klass();
1682 assert(vk->maybe_flat_in_array(), "should only be used for flat inline type arrays");
1683 // Adjust offset to omit oop header
1684 int base_offset = arrayOopDesc::base_offset_in_bytes(T_FLAT_ELEMENT) - vk->payload_offset();
1685 // Initialize all elements of the flat inline type array
1686 for (int i = 0; i < sv->field_size(); i++) {
1687 ObjectValue* val = sv->field_at(i)->as_ObjectValue();
1688 int offset = base_offset + (i << Klass::layout_helper_log2_element_size(vak->layout_helper()));
1689 reassign_fields_by_klass(vk, fr, reg_map, val, 0, (oop)obj, is_jvmci, offset, CHECK);
1690 if (!obj->is_null_free_array()) {
1691 jboolean null_marker_value;
1692 if (val->has_properties()) {
1693 null_marker_value = StackValue::create_stack_value(fr, reg_map, val->properties())->get_jint() & 1;
1694 } else {
1695 null_marker_value = 1;
1696 }
1697 obj->bool_field_put(offset + vk->null_marker_offset(), null_marker_value);
1698 }
1699 }
1700 }
1701
1702 // restore fields of all eliminated objects and arrays
1703 void Deoptimization::reassign_fields(frame* fr, RegisterMap* reg_map, GrowableArray<ScopeValue*>* objects, bool realloc_failures, bool is_jvmci, TRAPS) {
1704 for (int i = 0; i < objects->length(); i++) {
1705 assert(objects->at(i)->is_object(), "invalid debug information");
1706 ObjectValue* sv = (ObjectValue*) objects->at(i);
1707 Klass* k = java_lang_Class::as_Klass(sv->klass()->as_ConstantOopReadValue()->value()());
1708 k = get_refined_array_klass(k, fr, reg_map, sv, THREAD);
1709
1710 Handle obj = sv->value();
1711 assert(obj.not_null() || realloc_failures || sv->has_properties(), "reallocation was missed");
1712 #ifndef PRODUCT
1713 if (PrintDeoptimizationDetails) {
1714 tty->print_cr("reassign fields for object of type %s!", k->name()->as_C_string());
1715 }
1716 #endif // !PRODUCT
1717
1718 if (obj.is_null()) {
1719 continue;
1720 }
1721
1722 #if INCLUDE_JVMCI
1723 // Don't reassign fields of boxes that came from a cache. Caches may be in CDS.
1724 if (sv->is_auto_box() && ((AutoBoxObjectValue*) sv)->is_cached()) {
1725 continue;
1726 }
1727 #endif // INCLUDE_JVMCI
1728 if (EnableVectorSupport && VectorSupport::is_vector(k)) {
1729 assert(sv->field_size() == 1, "%s not a vector", k->name()->as_C_string());
1730 ScopeValue* payload = sv->field_at(0);
1731 if (payload->is_location() &&
1732 payload->as_LocationValue()->location().type() == Location::vector) {
1733 #ifndef PRODUCT
1734 if (PrintDeoptimizationDetails) {
1735 tty->print_cr("skip field reassignment for this vector - it should be assigned already");
1736 if (Verbose) {
1737 Handle obj = sv->value();
1738 k->oop_print_on(obj(), tty);
1739 }
1740 }
1741 #endif // !PRODUCT
1742 continue; // Such vector's value was already restored in VectorSupport::allocate_vector().
1743 }
1744 // Else fall-through to do assignment for scalar-replaced boxed vector representation
1745 // which could be restored after vector object allocation.
1746 }
1747 if (k->is_instance_klass()) {
1748 InstanceKlass* ik = InstanceKlass::cast(k);
1749 reassign_fields_by_klass(ik, fr, reg_map, sv, 0, obj(), is_jvmci, 0, CHECK);
1750 } else if (k->is_flatArray_klass()) {
1751 FlatArrayKlass* vak = FlatArrayKlass::cast(k);
1752 reassign_flat_array_elements(fr, reg_map, sv, (flatArrayOop) obj(), vak, is_jvmci, CHECK);
1753 } else if (k->is_typeArray_klass()) {
1754 TypeArrayKlass* ak = TypeArrayKlass::cast(k);
1755 reassign_type_array_elements(fr, reg_map, sv, (typeArrayOop) obj(), ak->element_type());
1756 } else if (k->is_refArray_klass()) {
1757 reassign_object_array_elements(fr, reg_map, sv, (objArrayOop) obj());
1758 }
1759 }
1760 // These objects may escape when we return to Interpreter after deoptimization.
1761 // We need barrier so that stores that initialize these objects can't be reordered
1762 // with subsequent stores that make these objects accessible by other threads.
1763 OrderAccess::storestore();
1764 }
1765
1766
1767 // relock objects for which synchronization was eliminated
1768 bool Deoptimization::relock_objects(JavaThread* thread, GrowableArray<MonitorInfo*>* monitors,
1769 JavaThread* deoptee_thread, frame& fr, int exec_mode, bool realloc_failures) {
1770 bool relocked_objects = false;
1771 for (int i = 0; i < monitors->length(); i++) {
1772 MonitorInfo* mon_info = monitors->at(i);
1773 if (mon_info->eliminated()) {
1774 assert(!mon_info->owner_is_scalar_replaced() || realloc_failures, "reallocation was missed");
1775 relocked_objects = true;
1776 if (!mon_info->owner_is_scalar_replaced()) {
1777 Handle obj(thread, mon_info->owner());
1778 markWord mark = obj->mark();
1779 if (exec_mode == Unpack_none) {
1780 if (mark.has_monitor()) {
1781 // defer relocking if the deoptee thread is currently waiting for obj
1782 ObjectMonitor* waiting_monitor = deoptee_thread->current_waiting_monitor();
1783 if (waiting_monitor != nullptr && waiting_monitor->object() == obj()) {
1784 assert(fr.is_deoptimized_frame(), "frame must be scheduled for deoptimization");
1785 if (UseObjectMonitorTable) {
1786 mon_info->lock()->clear_object_monitor_cache();
1787 }
1788 #ifdef ASSERT
1789 else {
1790 assert(!UseObjectMonitorTable, "must be");
1791 mon_info->lock()->set_bad_monitor_deopt();
1792 }
1793 #endif
1794 JvmtiDeferredUpdates::inc_relock_count_after_wait(deoptee_thread);
1795 continue;
1796 }
1797 }
1798 }
1799 BasicLock* lock = mon_info->lock();
1800 // We have lost information about the correct state of the lock stack.
1801 // Entering may create an invalid lock stack. Inflate the lock if it
1802 // was fast_locked to restore the valid lock stack.
1803 if (UseObjectMonitorTable) {
1804 // UseObjectMonitorTable expects the BasicLock cache to be either a
1805 // valid ObjectMonitor* or nullptr. Right now it is garbage, set it
1806 // to nullptr.
1807 lock->clear_object_monitor_cache();
1808 }
1809 ObjectSynchronizer::enter_for(obj, lock, deoptee_thread);
1810 if (deoptee_thread->lock_stack().contains(obj())) {
1811 ObjectSynchronizer::inflate_fast_locked_object(obj(), ObjectSynchronizer::InflateCause::inflate_cause_vm_internal,
1812 deoptee_thread, thread);
1813 }
1814 assert(mon_info->owner()->is_locked(), "object must be locked now");
1815 assert(obj->mark().has_monitor(), "must be");
1816 assert(!deoptee_thread->lock_stack().contains(obj()), "must be");
1817 assert(ObjectSynchronizer::read_monitor(thread, obj(), obj->mark())->has_owner(deoptee_thread), "must be");
1818 }
1819 }
1820 }
1821 return relocked_objects;
1822 }
1823 #endif // COMPILER2_OR_JVMCI
1824
1825 vframeArray* Deoptimization::create_vframeArray(JavaThread* thread, frame fr, RegisterMap *reg_map, GrowableArray<compiledVFrame*>* chunk, bool realloc_failures) {
1826 Events::log_deopt_message(thread, "DEOPT PACKING pc=" INTPTR_FORMAT " sp=" INTPTR_FORMAT, p2i(fr.pc()), p2i(fr.sp()));
1827
1828 // Register map for next frame (used for stack crawl). We capture
1829 // the state of the deopt'ing frame's caller. Thus if we need to
1830 // stuff a C2I adapter we can properly fill in the callee-save
1831 // register locations.
1832 frame caller = fr.sender(reg_map);
1833 int frame_size = pointer_delta_as_int(caller.sp(), fr.sp());
1834
1835 frame sender = caller;
1836
1837 // Since the Java thread being deoptimized will eventually adjust it's own stack,
1838 // the vframeArray containing the unpacking information is allocated in the C heap.
1839 // For Compiler1, the caller of the deoptimized frame is saved for use by unpack_frames().
1840 vframeArray* array = vframeArray::allocate(thread, frame_size, chunk, reg_map, sender, caller, fr, realloc_failures);
1841
1842 // Compare the vframeArray to the collected vframes
1843 assert(array->structural_compare(thread, chunk), "just checking");
1844
1845 if (TraceDeoptimization) {
1846 ResourceMark rm;
1847 stringStream st;
1848 st.print_cr("DEOPT PACKING thread=" INTPTR_FORMAT " vframeArray=" INTPTR_FORMAT, p2i(thread), p2i(array));
1849 st.print(" ");
1850 fr.print_on(&st);
1851 st.print_cr(" Virtual frames (innermost/newest first):");
1852 for (int index = 0; index < chunk->length(); index++) {
1853 compiledVFrame* vf = chunk->at(index);
1854 int bci = vf->raw_bci();
1855 const char* code_name;
1856 if (bci == SynchronizationEntryBCI) {
1857 code_name = "sync entry";
1858 } else {
1859 Bytecodes::Code code = vf->method()->code_at(bci);
1860 code_name = Bytecodes::name(code);
1861 }
1862
1863 st.print(" VFrame %d (" INTPTR_FORMAT ")", index, p2i(vf));
1864 st.print(" - %s", vf->method()->name_and_sig_as_C_string());
1865 st.print(" - %s", code_name);
1866 st.print_cr(" @ bci=%d ", bci);
1867 }
1868 tty->print_raw(st.freeze());
1869 tty->cr();
1870 }
1871
1872 return array;
1873 }
1874
1875 #if COMPILER2_OR_JVMCI
1876 void Deoptimization::pop_frames_failed_reallocs(JavaThread* thread, vframeArray* array) {
1877 // Reallocation of some scalar replaced objects failed. Record
1878 // that we need to pop all the interpreter frames for the
1879 // deoptimized compiled frame.
1880 assert(thread->frames_to_pop_failed_realloc() == 0, "missed frames to pop?");
1881 thread->set_frames_to_pop_failed_realloc(array->frames());
1882 // Unlock all monitors here otherwise the interpreter will see a
1883 // mix of locked and unlocked monitors (because of failed
1884 // reallocations of synchronized objects) and be confused.
1885 for (int i = 0; i < array->frames(); i++) {
1886 MonitorChunk* monitors = array->element(i)->monitors();
1887 if (monitors != nullptr) {
1888 // Unlock in reverse order starting from most nested monitor.
1889 for (int j = (monitors->number_of_monitors() - 1); j >= 0; j--) {
1890 BasicObjectLock* src = monitors->at(j);
1891 if (src->obj() != nullptr) {
1892 ObjectSynchronizer::exit(src->obj(), src->lock(), thread);
1893 }
1894 }
1895 array->element(i)->free_monitors();
1896 #ifdef ASSERT
1897 array->element(i)->set_removed_monitors();
1898 #endif
1899 }
1900 }
1901 }
1902 #endif
1903
1904 void Deoptimization::deoptimize_single_frame(JavaThread* thread, frame fr, Deoptimization::DeoptReason reason) {
1905 assert(fr.can_be_deoptimized(), "checking frame type");
1906
1907 gather_statistics(reason, Action_none, Bytecodes::_illegal);
1908
1909 if (LogCompilation && xtty != nullptr) {
1910 nmethod* nm = fr.cb()->as_nmethod_or_null();
1911 assert(nm != nullptr, "only compiled methods can deopt");
1912
1913 ttyLocker ttyl;
1914 xtty->begin_head("deoptimized thread='%zu' reason='%s' pc='" INTPTR_FORMAT "'",(uintx)thread->osthread()->thread_id(), trap_reason_name(reason), p2i(fr.pc()));
1915 nm->log_identity(xtty);
1916 xtty->end_head();
1917 for (ScopeDesc* sd = nm->scope_desc_at(fr.pc()); ; sd = sd->sender()) {
1918 xtty->begin_elem("jvms bci='%d'", sd->bci());
1919 xtty->method(sd->method());
1920 xtty->end_elem();
1921 if (sd->is_top()) break;
1922 }
1923 xtty->tail("deoptimized");
1924 }
1925
1926 Continuation::notify_deopt(thread, fr.sp());
1927
1928 // Patch the compiled method so that when execution returns to it we will
1929 // deopt the execution state and return to the interpreter.
1930 fr.deoptimize(thread);
1931 }
1932
1933 void Deoptimization::deoptimize(JavaThread* thread, frame fr, DeoptReason reason) {
1934 // Deoptimize only if the frame comes from compiled code.
1935 // Do not deoptimize the frame which is already patched
1936 // during the execution of the loops below.
1937 if (!fr.is_compiled_frame() || fr.is_deoptimized_frame()) {
1938 return;
1939 }
1940 ResourceMark rm;
1941 deoptimize_single_frame(thread, fr, reason);
1942 }
1943
1944 address Deoptimization::deoptimize_for_missing_exception_handler(nmethod* nm, bool make_not_entrant) {
1945 // there is no exception handler for this pc => deoptimize
1946 if (make_not_entrant) {
1947 nm->make_not_entrant(nmethod::InvalidationReason::MISSING_EXCEPTION_HANDLER);
1948 }
1949
1950 // Use Deoptimization::deoptimize for all of its side-effects:
1951 // gathering traps statistics, logging...
1952 // it also patches the return pc but we do not care about that
1953 // since we return a continuation to the deopt_blob below.
1954 JavaThread* thread = JavaThread::current();
1955 RegisterMap reg_map(thread,
1956 RegisterMap::UpdateMap::skip,
1957 RegisterMap::ProcessFrames::include,
1958 RegisterMap::WalkContinuation::skip);
1959 frame runtime_frame = thread->last_frame();
1960 frame caller_frame = runtime_frame.sender(®_map);
1961 assert(caller_frame.cb()->as_nmethod_or_null() == nm, "expect top frame compiled method");
1962
1963 Deoptimization::deoptimize(thread, caller_frame, Deoptimization::Reason_not_compiled_exception_handler);
1964
1965 if (!nm->is_compiled_by_jvmci()) {
1966 return SharedRuntime::deopt_blob()->unpack_with_exception_in_tls();
1967 }
1968
1969 #if INCLUDE_JVMCI
1970 // JVMCI support
1971 vframe* vf = vframe::new_vframe(&caller_frame, ®_map, thread);
1972 compiledVFrame* cvf = compiledVFrame::cast(vf);
1973 ScopeDesc* imm_scope = cvf->scope();
1974 MethodData* imm_mdo = get_method_data(thread, methodHandle(thread, imm_scope->method()), true);
1975 if (imm_mdo != nullptr) {
1976 // Lock to read ProfileData, and ensure lock is not broken by a safepoint
1977 MutexLocker ml(imm_mdo->extra_data_lock(), Mutex::_no_safepoint_check_flag);
1978
1979 ProfileData* pdata = imm_mdo->allocate_bci_to_data(imm_scope->bci(), nullptr);
1980 if (pdata != nullptr && pdata->is_BitData()) {
1981 BitData* bit_data = (BitData*) pdata;
1982 bit_data->set_exception_seen();
1983 }
1984 }
1985
1986
1987 MethodData* trap_mdo = get_method_data(thread, methodHandle(thread, nm->method()), true);
1988 if (trap_mdo != nullptr) {
1989 trap_mdo->inc_trap_count(Deoptimization::Reason_not_compiled_exception_handler);
1990 }
1991 #endif
1992
1993 return SharedRuntime::deopt_blob()->unpack_with_exception_in_tls();
1994 }
1995
1996 void Deoptimization::deoptimize_frame_internal(JavaThread* thread, intptr_t* id, DeoptReason reason) {
1997 assert(thread == Thread::current() ||
1998 thread->is_handshake_safe_for(Thread::current()) ||
1999 SafepointSynchronize::is_at_safepoint(),
2000 "can only deoptimize other thread at a safepoint/handshake");
2001 // Compute frame and register map based on thread and sp.
2002 RegisterMap reg_map(thread,
2003 RegisterMap::UpdateMap::skip,
2004 RegisterMap::ProcessFrames::include,
2005 RegisterMap::WalkContinuation::skip);
2006 frame fr = thread->last_frame();
2007 while (fr.id() != id) {
2008 fr = fr.sender(®_map);
2009 }
2010 deoptimize(thread, fr, reason);
2011 }
2012
2013
2014 void Deoptimization::deoptimize_frame(JavaThread* thread, intptr_t* id, DeoptReason reason) {
2015 Thread* current = Thread::current();
2016 if (thread == current || thread->is_handshake_safe_for(current)) {
2017 Deoptimization::deoptimize_frame_internal(thread, id, reason);
2018 } else {
2019 VM_DeoptimizeFrame deopt(thread, id, reason);
2020 VMThread::execute(&deopt);
2021 }
2022 }
2023
2024 void Deoptimization::deoptimize_frame(JavaThread* thread, intptr_t* id) {
2025 deoptimize_frame(thread, id, Reason_constraint);
2026 }
2027
2028 // JVMTI PopFrame support
2029 JRT_LEAF(void, Deoptimization::popframe_preserve_args(JavaThread* thread, int bytes_to_save, void* start_address))
2030 {
2031 assert(thread == JavaThread::current(), "pre-condition");
2032 thread->popframe_preserve_args(in_ByteSize(bytes_to_save), start_address);
2033 }
2034 JRT_END
2035
2036 MethodData*
2037 Deoptimization::get_method_data(JavaThread* thread, const methodHandle& m,
2038 bool create_if_missing) {
2039 JavaThread* THREAD = thread; // For exception macros.
2040 MethodData* mdo = m()->method_data();
2041 if (mdo == nullptr && create_if_missing && !HAS_PENDING_EXCEPTION) {
2042 // Build an MDO. Ignore errors like OutOfMemory;
2043 // that simply means we won't have an MDO to update.
2044 Method::build_profiling_method_data(m, THREAD);
2045 if (HAS_PENDING_EXCEPTION) {
2046 // Only metaspace OOM is expected. No Java code executed.
2047 assert((PENDING_EXCEPTION->is_a(vmClasses::OutOfMemoryError_klass())), "we expect only an OOM error here");
2048 CLEAR_PENDING_EXCEPTION;
2049 }
2050 mdo = m()->method_data();
2051 }
2052 return mdo;
2053 }
2054
2055 #if COMPILER2_OR_JVMCI
2056 void Deoptimization::load_class_by_index(const constantPoolHandle& constant_pool, int index, TRAPS) {
2057 // In case of an unresolved klass entry, load the class.
2058 // This path is exercised from case _ldc in Parse::do_one_bytecode,
2059 // and probably nowhere else.
2060 // Even that case would benefit from simply re-interpreting the
2061 // bytecode, without paying special attention to the class index.
2062 // So this whole "class index" feature should probably be removed.
2063
2064 if (constant_pool->tag_at(index).is_unresolved_klass()) {
2065 Klass* tk = constant_pool->klass_at(index, THREAD);
2066 if (HAS_PENDING_EXCEPTION) {
2067 // Exception happened during classloading. We ignore the exception here, since it
2068 // is going to be rethrown since the current activation is going to be deoptimized and
2069 // the interpreter will re-execute the bytecode.
2070 // Do not clear probable Async Exceptions.
2071 CLEAR_PENDING_NONASYNC_EXCEPTION;
2072 // Class loading called java code which may have caused a stack
2073 // overflow. If the exception was thrown right before the return
2074 // to the runtime the stack is no longer guarded. Reguard the
2075 // stack otherwise if we return to the uncommon trap blob and the
2076 // stack bang causes a stack overflow we crash.
2077 JavaThread* jt = THREAD;
2078 bool guard_pages_enabled = jt->stack_overflow_state()->reguard_stack_if_needed();
2079 assert(guard_pages_enabled, "stack banging in uncommon trap blob may cause crash");
2080 }
2081 return;
2082 }
2083
2084 assert(!constant_pool->tag_at(index).is_symbol(),
2085 "no symbolic names here, please");
2086 }
2087
2088 #if INCLUDE_JFR
2089
2090 class DeoptReasonSerializer : public JfrSerializer {
2091 public:
2092 void serialize(JfrCheckpointWriter& writer) {
2093 writer.write_count((u4)(Deoptimization::Reason_LIMIT + 1)); // + Reason::many (-1)
2094 for (int i = -1; i < Deoptimization::Reason_LIMIT; ++i) {
2095 writer.write_key((u8)i);
2096 writer.write(Deoptimization::trap_reason_name(i));
2097 }
2098 }
2099 };
2100
2101 class DeoptActionSerializer : public JfrSerializer {
2102 public:
2103 void serialize(JfrCheckpointWriter& writer) {
2104 static const u4 nof_actions = Deoptimization::Action_LIMIT;
2105 writer.write_count(nof_actions);
2106 for (u4 i = 0; i < Deoptimization::Action_LIMIT; ++i) {
2107 writer.write_key(i);
2108 writer.write(Deoptimization::trap_action_name((int)i));
2109 }
2110 }
2111 };
2112
2113 static void register_serializers() {
2114 static int critical_section = 0;
2115 if (1 == critical_section || AtomicAccess::cmpxchg(&critical_section, 0, 1) == 1) {
2116 return;
2117 }
2118 JfrSerializer::register_serializer(TYPE_DEOPTIMIZATIONREASON, true, new DeoptReasonSerializer());
2119 JfrSerializer::register_serializer(TYPE_DEOPTIMIZATIONACTION, true, new DeoptActionSerializer());
2120 }
2121
2122 static void post_deoptimization_event(nmethod* nm,
2123 const Method* method,
2124 int trap_bci,
2125 int instruction,
2126 Deoptimization::DeoptReason reason,
2127 Deoptimization::DeoptAction action) {
2128 assert(nm != nullptr, "invariant");
2129 assert(method != nullptr, "invariant");
2130 if (EventDeoptimization::is_enabled()) {
2131 static bool serializers_registered = false;
2132 if (!serializers_registered) {
2133 register_serializers();
2134 serializers_registered = true;
2135 }
2136 EventDeoptimization event;
2137 event.set_compileId(nm->compile_id());
2138 event.set_compiler(nm->compiler_type());
2139 event.set_method(method);
2140 event.set_lineNumber(method->line_number_from_bci(trap_bci));
2141 event.set_bci(trap_bci);
2142 event.set_instruction(instruction);
2143 event.set_reason(reason);
2144 event.set_action(action);
2145 event.commit();
2146 }
2147 }
2148
2149 #endif // INCLUDE_JFR
2150
2151 static void log_deopt(nmethod* nm, Method* tm, intptr_t pc, frame& fr, int trap_bci,
2152 const char* reason_name, const char* reason_action) {
2153 LogTarget(Debug, deoptimization) lt;
2154 if (lt.is_enabled()) {
2155 LogStream ls(lt);
2156 bool is_osr = nm->is_osr_method();
2157 ls.print("cid=%4d %s level=%d",
2158 nm->compile_id(), (is_osr ? "osr" : " "), nm->comp_level());
2159 ls.print(" %s", tm->name_and_sig_as_C_string());
2160 ls.print(" trap_bci=%d ", trap_bci);
2161 if (is_osr) {
2162 ls.print("osr_bci=%d ", nm->osr_entry_bci());
2163 }
2164 ls.print("%s ", reason_name);
2165 ls.print("%s ", reason_action);
2166 ls.print_cr("pc=" INTPTR_FORMAT " relative_pc=" INTPTR_FORMAT,
2167 pc, fr.pc() - nm->code_begin());
2168 }
2169 }
2170
2171 JRT_ENTRY(void, Deoptimization::uncommon_trap_inner(JavaThread* current, jint trap_request)) {
2172 HandleMark hm(current);
2173
2174 // uncommon_trap() is called at the beginning of the uncommon trap
2175 // handler. Note this fact before we start generating temporary frames
2176 // that can confuse an asynchronous stack walker. This counter is
2177 // decremented at the end of unpack_frames().
2178
2179 current->inc_in_deopt_handler();
2180
2181 #if INCLUDE_JVMCI
2182 // JVMCI might need to get an exception from the stack, which in turn requires the register map to be valid
2183 RegisterMap reg_map(current,
2184 RegisterMap::UpdateMap::include,
2185 RegisterMap::ProcessFrames::include,
2186 RegisterMap::WalkContinuation::skip);
2187 #else
2188 RegisterMap reg_map(current,
2189 RegisterMap::UpdateMap::skip,
2190 RegisterMap::ProcessFrames::include,
2191 RegisterMap::WalkContinuation::skip);
2192 #endif
2193 frame stub_frame = current->last_frame();
2194 frame fr = stub_frame.sender(®_map);
2195
2196 // Log a message
2197 Events::log_deopt_message(current, "Uncommon trap: trap_request=" INT32_FORMAT_X_0 " fr.pc=" INTPTR_FORMAT " relative=" INTPTR_FORMAT,
2198 trap_request, p2i(fr.pc()), fr.pc() - fr.cb()->code_begin());
2199
2200 {
2201 ResourceMark rm;
2202
2203 DeoptReason reason = trap_request_reason(trap_request);
2204 DeoptAction action = trap_request_action(trap_request);
2205 #if INCLUDE_JVMCI
2206 int debug_id = trap_request_debug_id(trap_request);
2207 #endif
2208 jint unloaded_class_index = trap_request_index(trap_request); // CP idx or -1
2209
2210 vframe* vf = vframe::new_vframe(&fr, ®_map, current);
2211 compiledVFrame* cvf = compiledVFrame::cast(vf);
2212
2213 nmethod* nm = cvf->code();
2214
2215 ScopeDesc* trap_scope = cvf->scope();
2216
2217 bool is_receiver_constraint_failure = COMPILER2_PRESENT(VerifyReceiverTypes &&) (reason == Deoptimization::Reason_receiver_constraint);
2218
2219 if (is_receiver_constraint_failure) {
2220 tty->print_cr(" bci=%d pc=" INTPTR_FORMAT ", relative_pc=" INTPTR_FORMAT ", method=%s" JVMCI_ONLY(", debug_id=%d"),
2221 trap_scope->bci(), p2i(fr.pc()), fr.pc() - nm->code_begin(), trap_scope->method()->name_and_sig_as_C_string()
2222 JVMCI_ONLY(COMMA debug_id));
2223 }
2224
2225 methodHandle trap_method(current, trap_scope->method());
2226 int trap_bci = trap_scope->bci();
2227 #if INCLUDE_JVMCI
2228 jlong speculation = current->pending_failed_speculation();
2229 if (nm->is_compiled_by_jvmci()) {
2230 nm->update_speculation(current);
2231 } else {
2232 assert(speculation == 0, "There should not be a speculation for methods compiled by non-JVMCI compilers");
2233 }
2234
2235 if (trap_bci == SynchronizationEntryBCI) {
2236 trap_bci = 0;
2237 current->set_pending_monitorenter(true);
2238 }
2239
2240 if (reason == Deoptimization::Reason_transfer_to_interpreter) {
2241 current->set_pending_transfer_to_interpreter(true);
2242 }
2243 #endif
2244
2245 Bytecodes::Code trap_bc = trap_method->java_code_at(trap_bci);
2246 // Record this event in the histogram.
2247 gather_statistics(reason, action, trap_bc);
2248
2249 // Ensure that we can record deopt. history:
2250 bool create_if_missing = ProfileTraps;
2251
2252 methodHandle profiled_method;
2253 #if INCLUDE_JVMCI
2254 if (nm->is_compiled_by_jvmci()) {
2255 profiled_method = methodHandle(current, nm->method());
2256 } else {
2257 profiled_method = trap_method;
2258 }
2259 #else
2260 profiled_method = trap_method;
2261 #endif
2262
2263 MethodData* trap_mdo =
2264 get_method_data(current, profiled_method, create_if_missing);
2265
2266 { // Log Deoptimization event for JFR, UL and event system
2267 Method* tm = trap_method();
2268 const char* reason_name = trap_reason_name(reason);
2269 const char* reason_action = trap_action_name(action);
2270 intptr_t pc = p2i(fr.pc());
2271
2272 JFR_ONLY(post_deoptimization_event(nm, tm, trap_bci, trap_bc, reason, action);)
2273 log_deopt(nm, tm, pc, fr, trap_bci, reason_name, reason_action);
2274 Events::log_deopt_message(current, "Uncommon trap: reason=%s action=%s pc=" INTPTR_FORMAT " method=%s @ %d %s",
2275 reason_name, reason_action, pc,
2276 tm->name_and_sig_as_C_string(), trap_bci, nm->compiler_name());
2277 }
2278
2279 // Print a bunch of diagnostics, if requested.
2280 if (TraceDeoptimization || LogCompilation || is_receiver_constraint_failure) {
2281 ResourceMark rm;
2282
2283 // Lock to read ProfileData, and ensure lock is not broken by a safepoint
2284 // We must do this already now, since we cannot acquire this lock while
2285 // holding the tty lock (lock ordering by rank).
2286 MutexLocker ml(trap_mdo->extra_data_lock(), Mutex::_no_safepoint_check_flag);
2287
2288 ttyLocker ttyl;
2289
2290 char buf[100];
2291 if (xtty != nullptr) {
2292 xtty->begin_head("uncommon_trap thread='%zu' %s",
2293 os::current_thread_id(),
2294 format_trap_request(buf, sizeof(buf), trap_request));
2295 #if INCLUDE_JVMCI
2296 if (speculation != 0) {
2297 xtty->print(" speculation='" JLONG_FORMAT "'", speculation);
2298 }
2299 #endif
2300 nm->log_identity(xtty);
2301 }
2302 Symbol* class_name = nullptr;
2303 bool unresolved = false;
2304 if (unloaded_class_index >= 0) {
2305 constantPoolHandle constants (current, trap_method->constants());
2306 if (constants->tag_at(unloaded_class_index).is_unresolved_klass()) {
2307 class_name = constants->klass_name_at(unloaded_class_index);
2308 unresolved = true;
2309 if (xtty != nullptr)
2310 xtty->print(" unresolved='1'");
2311 } else if (constants->tag_at(unloaded_class_index).is_symbol()) {
2312 class_name = constants->symbol_at(unloaded_class_index);
2313 }
2314 if (xtty != nullptr)
2315 xtty->name(class_name);
2316 }
2317 if (xtty != nullptr && trap_mdo != nullptr && (int)reason < (int)MethodData::_trap_hist_limit) {
2318 // Dump the relevant MDO state.
2319 // This is the deopt count for the current reason, any previous
2320 // reasons or recompiles seen at this point.
2321 int dcnt = trap_mdo->trap_count(reason);
2322 if (dcnt != 0)
2323 xtty->print(" count='%d'", dcnt);
2324
2325 // We need to lock to read the ProfileData. But to keep the locks ordered, we need to
2326 // lock extra_data_lock before the tty lock.
2327 ProfileData* pdata = trap_mdo->bci_to_data(trap_bci);
2328 int dos = (pdata == nullptr)? 0: pdata->trap_state();
2329 if (dos != 0) {
2330 xtty->print(" state='%s'", format_trap_state(buf, sizeof(buf), dos));
2331 if (trap_state_is_recompiled(dos)) {
2332 int recnt2 = trap_mdo->overflow_recompile_count();
2333 if (recnt2 != 0)
2334 xtty->print(" recompiles2='%d'", recnt2);
2335 }
2336 }
2337 }
2338 if (xtty != nullptr) {
2339 xtty->stamp();
2340 xtty->end_head();
2341 }
2342 if (TraceDeoptimization) { // make noise on the tty
2343 stringStream st;
2344 st.print("UNCOMMON TRAP method=%s", trap_scope->method()->name_and_sig_as_C_string());
2345 st.print(" bci=%d pc=" INTPTR_FORMAT ", relative_pc=" INTPTR_FORMAT JVMCI_ONLY(", debug_id=%d"),
2346 trap_scope->bci(), p2i(fr.pc()), fr.pc() - nm->code_begin() JVMCI_ONLY(COMMA debug_id));
2347 st.print(" compiler=%s compile_id=%d", nm->compiler_name(), nm->compile_id());
2348 #if INCLUDE_JVMCI
2349 if (nm->is_compiled_by_jvmci()) {
2350 const char* installed_code_name = nm->jvmci_name();
2351 if (installed_code_name != nullptr) {
2352 st.print(" (JVMCI: installed code name=%s) ", installed_code_name);
2353 }
2354 }
2355 #endif
2356 st.print(" (@" INTPTR_FORMAT ") thread=%zu reason=%s action=%s unloaded_class_index=%d" JVMCI_ONLY(" debug_id=%d"),
2357 p2i(fr.pc()),
2358 os::current_thread_id(),
2359 trap_reason_name(reason),
2360 trap_action_name(action),
2361 unloaded_class_index
2362 #if INCLUDE_JVMCI
2363 , debug_id
2364 #endif
2365 );
2366 if (class_name != nullptr) {
2367 st.print(unresolved ? " unresolved class: " : " symbol: ");
2368 class_name->print_symbol_on(&st);
2369 }
2370 st.cr();
2371 tty->print_raw(st.freeze());
2372 }
2373 if (xtty != nullptr) {
2374 // Log the precise location of the trap.
2375 for (ScopeDesc* sd = trap_scope; ; sd = sd->sender()) {
2376 xtty->begin_elem("jvms bci='%d'", sd->bci());
2377 xtty->method(sd->method());
2378 xtty->end_elem();
2379 if (sd->is_top()) break;
2380 }
2381 xtty->tail("uncommon_trap");
2382 }
2383 }
2384 // (End diagnostic printout.)
2385
2386 if (is_receiver_constraint_failure) {
2387 fatal("missing receiver type check");
2388 }
2389
2390 // Load class if necessary
2391 if (unloaded_class_index >= 0) {
2392 constantPoolHandle constants(current, trap_method->constants());
2393 load_class_by_index(constants, unloaded_class_index, THREAD);
2394 }
2395
2396 // Flush the nmethod if necessary and desirable.
2397 //
2398 // We need to avoid situations where we are re-flushing the nmethod
2399 // because of a hot deoptimization site. Repeated flushes at the same
2400 // point need to be detected by the compiler and avoided. If the compiler
2401 // cannot avoid them (or has a bug and "refuses" to avoid them), this
2402 // module must take measures to avoid an infinite cycle of recompilation
2403 // and deoptimization. There are several such measures:
2404 //
2405 // 1. If a recompilation is ordered a second time at some site X
2406 // and for the same reason R, the action is adjusted to 'reinterpret',
2407 // to give the interpreter time to exercise the method more thoroughly.
2408 // If this happens, the method's overflow_recompile_count is incremented.
2409 //
2410 // 2. If the compiler fails to reduce the deoptimization rate, then
2411 // the method's overflow_recompile_count will begin to exceed the set
2412 // limit PerBytecodeRecompilationCutoff. If this happens, the action
2413 // is adjusted to 'make_not_compilable', and the method is abandoned
2414 // to the interpreter. This is a performance hit for hot methods,
2415 // but is better than a disastrous infinite cycle of recompilations.
2416 // (Actually, only the method containing the site X is abandoned.)
2417 //
2418 // 3. In parallel with the previous measures, if the total number of
2419 // recompilations of a method exceeds the much larger set limit
2420 // PerMethodRecompilationCutoff, the method is abandoned.
2421 // This should only happen if the method is very large and has
2422 // many "lukewarm" deoptimizations. The code which enforces this
2423 // limit is elsewhere (class nmethod, class Method).
2424 //
2425 // Note that the per-BCI 'is_recompiled' bit gives the compiler one chance
2426 // to recompile at each bytecode independently of the per-BCI cutoff.
2427 //
2428 // The decision to update code is up to the compiler, and is encoded
2429 // in the Action_xxx code. If the compiler requests Action_none
2430 // no trap state is changed, no compiled code is changed, and the
2431 // computation suffers along in the interpreter.
2432 //
2433 // The other action codes specify various tactics for decompilation
2434 // and recompilation. Action_maybe_recompile is the loosest, and
2435 // allows the compiled code to stay around until enough traps are seen,
2436 // and until the compiler gets around to recompiling the trapping method.
2437 //
2438 // The other actions cause immediate removal of the present code.
2439
2440 // Traps caused by injected profile shouldn't pollute trap counts.
2441 bool injected_profile_trap = trap_method->has_injected_profile() &&
2442 (reason == Reason_intrinsic || reason == Reason_unreached);
2443
2444 bool update_trap_state = (reason != Reason_tenured) && !injected_profile_trap;
2445 bool make_not_entrant = false;
2446 bool make_not_compilable = false;
2447 bool reprofile = false;
2448 switch (action) {
2449 case Action_none:
2450 // Keep the old code.
2451 update_trap_state = false;
2452 break;
2453 case Action_maybe_recompile:
2454 // Do not need to invalidate the present code, but we can
2455 // initiate another
2456 // Start compiler without (necessarily) invalidating the nmethod.
2457 // The system will tolerate the old code, but new code should be
2458 // generated when possible.
2459 break;
2460 case Action_reinterpret:
2461 // Go back into the interpreter for a while, and then consider
2462 // recompiling form scratch.
2463 make_not_entrant = true;
2464 // Reset invocation counter for outer most method.
2465 // This will allow the interpreter to exercise the bytecodes
2466 // for a while before recompiling.
2467 // By contrast, Action_make_not_entrant is immediate.
2468 //
2469 // Note that the compiler will track null_check, null_assert,
2470 // range_check, and class_check events and log them as if they
2471 // had been traps taken from compiled code. This will update
2472 // the MDO trap history so that the next compilation will
2473 // properly detect hot trap sites.
2474 reprofile = true;
2475 break;
2476 case Action_make_not_entrant:
2477 // Request immediate recompilation, and get rid of the old code.
2478 // Make them not entrant, so next time they are called they get
2479 // recompiled. Unloaded classes are loaded now so recompile before next
2480 // time they are called. Same for uninitialized. The interpreter will
2481 // link the missing class, if any.
2482 make_not_entrant = true;
2483 break;
2484 case Action_make_not_compilable:
2485 // Give up on compiling this method at all.
2486 make_not_entrant = true;
2487 make_not_compilable = true;
2488 break;
2489 default:
2490 ShouldNotReachHere();
2491 }
2492
2493 #if INCLUDE_JVMCI
2494 // Deoptimization count is used by the CompileBroker to reason about compilations
2495 // it requests so do not pollute the count for deoptimizations in non-default (i.e.
2496 // non-CompilerBroker) compilations.
2497 if (nm->jvmci_skip_profile_deopt()) {
2498 update_trap_state = false;
2499 }
2500 #endif
2501 // Setting +ProfileTraps fixes the following, on all platforms:
2502 // The result is infinite heroic-opt-uncommon-trap/deopt/recompile cycles, since the
2503 // recompile relies on a MethodData* to record heroic opt failures.
2504
2505 // Whether the interpreter is producing MDO data or not, we also need
2506 // to use the MDO to detect hot deoptimization points and control
2507 // aggressive optimization.
2508 bool inc_recompile_count = false;
2509
2510 // Lock to read ProfileData, and ensure lock is not broken by a safepoint
2511 ConditionalMutexLocker ml((trap_mdo != nullptr) ? trap_mdo->extra_data_lock() : nullptr,
2512 (trap_mdo != nullptr),
2513 Mutex::_no_safepoint_check_flag);
2514 ProfileData* pdata = nullptr;
2515 if (ProfileTraps && CompilerConfig::is_c2_or_jvmci_compiler_enabled() && update_trap_state && trap_mdo != nullptr) {
2516 assert(trap_mdo == get_method_data(current, profiled_method, false), "sanity");
2517 uint this_trap_count = 0;
2518 bool maybe_prior_trap = false;
2519 bool maybe_prior_recompile = false;
2520
2521 pdata = query_update_method_data(trap_mdo, trap_bci, reason, true,
2522 #if INCLUDE_JVMCI
2523 nm->is_compiled_by_jvmci() && nm->is_osr_method(),
2524 #endif
2525 nm->method(),
2526 //outputs:
2527 this_trap_count,
2528 maybe_prior_trap,
2529 maybe_prior_recompile);
2530 // Because the interpreter also counts null, div0, range, and class
2531 // checks, these traps from compiled code are double-counted.
2532 // This is harmless; it just means that the PerXTrapLimit values
2533 // are in effect a little smaller than they look.
2534
2535 DeoptReason per_bc_reason = reason_recorded_per_bytecode_if_any(reason);
2536 if (per_bc_reason != Reason_none) {
2537 // Now take action based on the partially known per-BCI history.
2538 if (maybe_prior_trap
2539 && this_trap_count >= (uint)PerBytecodeTrapLimit) {
2540 // If there are too many traps at this BCI, force a recompile.
2541 // This will allow the compiler to see the limit overflow, and
2542 // take corrective action, if possible. The compiler generally
2543 // does not use the exact PerBytecodeTrapLimit value, but instead
2544 // changes its tactics if it sees any traps at all. This provides
2545 // a little hysteresis, delaying a recompile until a trap happens
2546 // several times.
2547 //
2548 // Actually, since there is only one bit of counter per BCI,
2549 // the possible per-BCI counts are {0,1,(per-method count)}.
2550 // This produces accurate results if in fact there is only
2551 // one hot trap site, but begins to get fuzzy if there are
2552 // many sites. For example, if there are ten sites each
2553 // trapping two or more times, they each get the blame for
2554 // all of their traps.
2555 make_not_entrant = true;
2556 }
2557
2558 // Detect repeated recompilation at the same BCI, and enforce a limit.
2559 if (make_not_entrant && maybe_prior_recompile) {
2560 // More than one recompile at this point.
2561 inc_recompile_count = maybe_prior_trap;
2562 }
2563 } else {
2564 // For reasons which are not recorded per-bytecode, we simply
2565 // force recompiles unconditionally.
2566 // (Note that PerMethodRecompilationCutoff is enforced elsewhere.)
2567 make_not_entrant = true;
2568 }
2569
2570 // Go back to the compiler if there are too many traps in this method.
2571 if (this_trap_count >= per_method_trap_limit(reason)) {
2572 // If there are too many traps in this method, force a recompile.
2573 // This will allow the compiler to see the limit overflow, and
2574 // take corrective action, if possible.
2575 // (This condition is an unlikely backstop only, because the
2576 // PerBytecodeTrapLimit is more likely to take effect first,
2577 // if it is applicable.)
2578 make_not_entrant = true;
2579 }
2580
2581 // Here's more hysteresis: If there has been a recompile at
2582 // this trap point already, run the method in the interpreter
2583 // for a while to exercise it more thoroughly.
2584 if (make_not_entrant && maybe_prior_recompile && maybe_prior_trap) {
2585 reprofile = true;
2586 }
2587 }
2588
2589 // Take requested actions on the method:
2590
2591 // Recompile
2592 if (make_not_entrant) {
2593 if (!nm->make_not_entrant(nmethod::InvalidationReason::UNCOMMON_TRAP)) {
2594 return; // the call did not change nmethod's state
2595 }
2596
2597 if (pdata != nullptr) {
2598 // Record the recompilation event, if any.
2599 int tstate0 = pdata->trap_state();
2600 int tstate1 = trap_state_set_recompiled(tstate0, true);
2601 if (tstate1 != tstate0)
2602 pdata->set_trap_state(tstate1);
2603 }
2604
2605 // For code aging we count traps separately here, using make_not_entrant()
2606 // as a guard against simultaneous deopts in multiple threads.
2607 if (reason == Reason_tenured && trap_mdo != nullptr) {
2608 trap_mdo->inc_tenure_traps();
2609 }
2610 }
2611 if (inc_recompile_count) {
2612 trap_mdo->inc_overflow_recompile_count();
2613 if ((uint)trap_mdo->overflow_recompile_count() >
2614 (uint)PerBytecodeRecompilationCutoff) {
2615 // Give up on the method containing the bad BCI.
2616 if (trap_method() == nm->method()) {
2617 make_not_compilable = true;
2618 } else {
2619 trap_method->set_not_compilable("overflow_recompile_count > PerBytecodeRecompilationCutoff", CompLevel_full_optimization);
2620 // But give grace to the enclosing nm->method().
2621 }
2622 }
2623 }
2624
2625 // Reprofile
2626 if (reprofile) {
2627 CompilationPolicy::reprofile(trap_scope, nm->is_osr_method());
2628 }
2629
2630 // Give up compiling
2631 if (make_not_compilable && !nm->method()->is_not_compilable(CompLevel_full_optimization)) {
2632 assert(make_not_entrant, "consistent");
2633 nm->method()->set_not_compilable("give up compiling", CompLevel_full_optimization);
2634 }
2635
2636 if (ProfileExceptionHandlers && trap_mdo != nullptr) {
2637 BitData* exception_handler_data = trap_mdo->exception_handler_bci_to_data_or_null(trap_bci);
2638 if (exception_handler_data != nullptr) {
2639 // uncommon trap at the start of an exception handler.
2640 // C2 generates these for un-entered exception handlers.
2641 // mark the handler as entered to avoid generating
2642 // another uncommon trap the next time the handler is compiled
2643 exception_handler_data->set_exception_handler_entered();
2644 }
2645 }
2646
2647 } // Free marked resources
2648
2649 }
2650 JRT_END
2651
2652 ProfileData*
2653 Deoptimization::query_update_method_data(MethodData* trap_mdo,
2654 int trap_bci,
2655 Deoptimization::DeoptReason reason,
2656 bool update_total_trap_count,
2657 #if INCLUDE_JVMCI
2658 bool is_osr,
2659 #endif
2660 Method* compiled_method,
2661 //outputs:
2662 uint& ret_this_trap_count,
2663 bool& ret_maybe_prior_trap,
2664 bool& ret_maybe_prior_recompile) {
2665 trap_mdo->check_extra_data_locked();
2666
2667 bool maybe_prior_trap = false;
2668 bool maybe_prior_recompile = false;
2669 uint this_trap_count = 0;
2670 if (update_total_trap_count) {
2671 uint idx = reason;
2672 #if INCLUDE_JVMCI
2673 if (is_osr) {
2674 // Upper half of history array used for traps in OSR compilations
2675 idx += Reason_TRAP_HISTORY_LENGTH;
2676 }
2677 #endif
2678 uint prior_trap_count = trap_mdo->trap_count(idx);
2679 this_trap_count = trap_mdo->inc_trap_count(idx);
2680
2681 // If the runtime cannot find a place to store trap history,
2682 // it is estimated based on the general condition of the method.
2683 // If the method has ever been recompiled, or has ever incurred
2684 // a trap with the present reason , then this BCI is assumed
2685 // (pessimistically) to be the culprit.
2686 maybe_prior_trap = (prior_trap_count != 0);
2687 maybe_prior_recompile = (trap_mdo->decompile_count() != 0);
2688 }
2689 ProfileData* pdata = nullptr;
2690
2691
2692 // For reasons which are recorded per bytecode, we check per-BCI data.
2693 DeoptReason per_bc_reason = reason_recorded_per_bytecode_if_any(reason);
2694 assert(per_bc_reason != Reason_none || update_total_trap_count, "must be");
2695 if (per_bc_reason != Reason_none) {
2696 // Find the profile data for this BCI. If there isn't one,
2697 // try to allocate one from the MDO's set of spares.
2698 // This will let us detect a repeated trap at this point.
2699 pdata = trap_mdo->allocate_bci_to_data(trap_bci, reason_is_speculate(reason) ? compiled_method : nullptr);
2700
2701 if (pdata != nullptr) {
2702 if (reason_is_speculate(reason) && !pdata->is_SpeculativeTrapData()) {
2703 if (LogCompilation && xtty != nullptr) {
2704 ttyLocker ttyl;
2705 // no more room for speculative traps in this MDO
2706 xtty->elem("speculative_traps_oom");
2707 }
2708 }
2709 // Query the trap state of this profile datum.
2710 int tstate0 = pdata->trap_state();
2711 if (!trap_state_has_reason(tstate0, per_bc_reason))
2712 maybe_prior_trap = false;
2713 if (!trap_state_is_recompiled(tstate0))
2714 maybe_prior_recompile = false;
2715
2716 // Update the trap state of this profile datum.
2717 int tstate1 = tstate0;
2718 // Record the reason.
2719 tstate1 = trap_state_add_reason(tstate1, per_bc_reason);
2720 // Store the updated state on the MDO, for next time.
2721 if (tstate1 != tstate0)
2722 pdata->set_trap_state(tstate1);
2723 } else {
2724 if (LogCompilation && xtty != nullptr) {
2725 ttyLocker ttyl;
2726 // Missing MDP? Leave a small complaint in the log.
2727 xtty->elem("missing_mdp bci='%d'", trap_bci);
2728 }
2729 }
2730 }
2731
2732 // Return results:
2733 ret_this_trap_count = this_trap_count;
2734 ret_maybe_prior_trap = maybe_prior_trap;
2735 ret_maybe_prior_recompile = maybe_prior_recompile;
2736 return pdata;
2737 }
2738
2739 void
2740 Deoptimization::update_method_data_from_interpreter(MethodData* trap_mdo, int trap_bci, int reason) {
2741 ResourceMark rm;
2742 // Ignored outputs:
2743 uint ignore_this_trap_count;
2744 bool ignore_maybe_prior_trap;
2745 bool ignore_maybe_prior_recompile;
2746 assert(!reason_is_speculate(reason), "reason speculate only used by compiler");
2747 // JVMCI uses the total counts to determine if deoptimizations are happening too frequently -> do not adjust total counts
2748 bool update_total_counts = true JVMCI_ONLY( && !UseJVMCICompiler);
2749
2750 // Lock to read ProfileData, and ensure lock is not broken by a safepoint
2751 MutexLocker ml(trap_mdo->extra_data_lock(), Mutex::_no_safepoint_check_flag);
2752
2753 query_update_method_data(trap_mdo, trap_bci,
2754 (DeoptReason)reason,
2755 update_total_counts,
2756 #if INCLUDE_JVMCI
2757 false,
2758 #endif
2759 nullptr,
2760 ignore_this_trap_count,
2761 ignore_maybe_prior_trap,
2762 ignore_maybe_prior_recompile);
2763 }
2764
2765 Deoptimization::UnrollBlock* Deoptimization::uncommon_trap(JavaThread* current, jint trap_request, jint exec_mode) {
2766 // Enable WXWrite: current function is called from methods compiled by C2 directly
2767 MACOS_AARCH64_ONLY(ThreadWXEnable wx(WXWrite, current));
2768
2769 // Still in Java no safepoints
2770 {
2771 // This enters VM and may safepoint
2772 uncommon_trap_inner(current, trap_request);
2773 }
2774 HandleMark hm(current);
2775 return fetch_unroll_info_helper(current, exec_mode);
2776 }
2777
2778 // Local derived constants.
2779 // Further breakdown of DataLayout::trap_state, as promised by DataLayout.
2780 const int DS_REASON_MASK = ((uint)DataLayout::trap_mask) >> 1;
2781 const int DS_RECOMPILE_BIT = DataLayout::trap_mask - DS_REASON_MASK;
2782
2783 //---------------------------trap_state_reason---------------------------------
2784 Deoptimization::DeoptReason
2785 Deoptimization::trap_state_reason(int trap_state) {
2786 // This assert provides the link between the width of DataLayout::trap_bits
2787 // and the encoding of "recorded" reasons. It ensures there are enough
2788 // bits to store all needed reasons in the per-BCI MDO profile.
2789 assert(DS_REASON_MASK >= Reason_RECORDED_LIMIT, "enough bits");
2790 int recompile_bit = (trap_state & DS_RECOMPILE_BIT);
2791 trap_state -= recompile_bit;
2792 if (trap_state == DS_REASON_MASK) {
2793 return Reason_many;
2794 } else {
2795 assert((int)Reason_none == 0, "state=0 => Reason_none");
2796 return (DeoptReason)trap_state;
2797 }
2798 }
2799 //-------------------------trap_state_has_reason-------------------------------
2800 int Deoptimization::trap_state_has_reason(int trap_state, int reason) {
2801 assert(reason_is_recorded_per_bytecode((DeoptReason)reason), "valid reason");
2802 assert(DS_REASON_MASK >= Reason_RECORDED_LIMIT, "enough bits");
2803 int recompile_bit = (trap_state & DS_RECOMPILE_BIT);
2804 trap_state -= recompile_bit;
2805 if (trap_state == DS_REASON_MASK) {
2806 return -1; // true, unspecifically (bottom of state lattice)
2807 } else if (trap_state == reason) {
2808 return 1; // true, definitely
2809 } else if (trap_state == 0) {
2810 return 0; // false, definitely (top of state lattice)
2811 } else {
2812 return 0; // false, definitely
2813 }
2814 }
2815 //-------------------------trap_state_add_reason-------------------------------
2816 int Deoptimization::trap_state_add_reason(int trap_state, int reason) {
2817 assert(reason_is_recorded_per_bytecode((DeoptReason)reason) || reason == Reason_many, "valid reason");
2818 int recompile_bit = (trap_state & DS_RECOMPILE_BIT);
2819 trap_state -= recompile_bit;
2820 if (trap_state == DS_REASON_MASK) {
2821 return trap_state + recompile_bit; // already at state lattice bottom
2822 } else if (trap_state == reason) {
2823 return trap_state + recompile_bit; // the condition is already true
2824 } else if (trap_state == 0) {
2825 return reason + recompile_bit; // no condition has yet been true
2826 } else {
2827 return DS_REASON_MASK + recompile_bit; // fall to state lattice bottom
2828 }
2829 }
2830 //-----------------------trap_state_is_recompiled------------------------------
2831 bool Deoptimization::trap_state_is_recompiled(int trap_state) {
2832 return (trap_state & DS_RECOMPILE_BIT) != 0;
2833 }
2834 //-----------------------trap_state_set_recompiled-----------------------------
2835 int Deoptimization::trap_state_set_recompiled(int trap_state, bool z) {
2836 if (z) return trap_state | DS_RECOMPILE_BIT;
2837 else return trap_state & ~DS_RECOMPILE_BIT;
2838 }
2839 //---------------------------format_trap_state---------------------------------
2840 // This is used for debugging and diagnostics, including LogFile output.
2841 const char* Deoptimization::format_trap_state(char* buf, size_t buflen,
2842 int trap_state) {
2843 assert(buflen > 0, "sanity");
2844 DeoptReason reason = trap_state_reason(trap_state);
2845 bool recomp_flag = trap_state_is_recompiled(trap_state);
2846 // Re-encode the state from its decoded components.
2847 int decoded_state = 0;
2848 if (reason_is_recorded_per_bytecode(reason) || reason == Reason_many)
2849 decoded_state = trap_state_add_reason(decoded_state, reason);
2850 if (recomp_flag)
2851 decoded_state = trap_state_set_recompiled(decoded_state, recomp_flag);
2852 // If the state re-encodes properly, format it symbolically.
2853 // Because this routine is used for debugging and diagnostics,
2854 // be robust even if the state is a strange value.
2855 size_t len;
2856 if (decoded_state != trap_state) {
2857 // Random buggy state that doesn't decode??
2858 len = jio_snprintf(buf, buflen, "#%d", trap_state);
2859 } else {
2860 len = jio_snprintf(buf, buflen, "%s%s",
2861 trap_reason_name(reason),
2862 recomp_flag ? " recompiled" : "");
2863 }
2864 return buf;
2865 }
2866
2867
2868 //--------------------------------statics--------------------------------------
2869 const char* Deoptimization::_trap_reason_name[] = {
2870 // Note: Keep this in sync. with enum DeoptReason.
2871 "none",
2872 "null_check",
2873 "null_assert" JVMCI_ONLY("_or_unreached0"),
2874 "range_check",
2875 "class_check",
2876 "array_check",
2877 "intrinsic" JVMCI_ONLY("_or_type_checked_inlining"),
2878 "bimorphic" JVMCI_ONLY("_or_optimized_type_check"),
2879 "profile_predicate",
2880 "auto_vectorization_check",
2881 "unloaded",
2882 "uninitialized",
2883 "initialized",
2884 "unreached",
2885 "unhandled",
2886 "constraint",
2887 "div0_check",
2888 "age",
2889 "predicate",
2890 "loop_limit_check",
2891 "speculate_class_check",
2892 "speculate_null_check",
2893 "speculate_null_assert",
2894 "unstable_if",
2895 "unstable_fused_if",
2896 "receiver_constraint",
2897 "not_compiled_exception_handler",
2898 "short_running_loop" JVMCI_ONLY("_or_aliasing"),
2899 #if INCLUDE_JVMCI
2900 "transfer_to_interpreter",
2901 "unresolved",
2902 "jsr_mismatch",
2903 #endif
2904 "tenured"
2905 };
2906 const char* Deoptimization::_trap_action_name[] = {
2907 // Note: Keep this in sync. with enum DeoptAction.
2908 "none",
2909 "maybe_recompile",
2910 "reinterpret",
2911 "make_not_entrant",
2912 "make_not_compilable"
2913 };
2914
2915 const char* Deoptimization::trap_reason_name(int reason) {
2916 // Check that every reason has a name
2917 STATIC_ASSERT(sizeof(_trap_reason_name)/sizeof(const char*) == Reason_LIMIT);
2918
2919 if (reason == Reason_many) return "many";
2920 if ((uint)reason < Reason_LIMIT)
2921 return _trap_reason_name[reason];
2922 static char buf[20];
2923 os::snprintf_checked(buf, sizeof(buf), "reason%d", reason);
2924 return buf;
2925 }
2926 const char* Deoptimization::trap_action_name(int action) {
2927 // Check that every action has a name
2928 STATIC_ASSERT(sizeof(_trap_action_name)/sizeof(const char*) == Action_LIMIT);
2929
2930 if ((uint)action < Action_LIMIT)
2931 return _trap_action_name[action];
2932 static char buf[20];
2933 os::snprintf_checked(buf, sizeof(buf), "action%d", action);
2934 return buf;
2935 }
2936
2937 // This is used for debugging and diagnostics, including LogFile output.
2938 const char* Deoptimization::format_trap_request(char* buf, size_t buflen,
2939 int trap_request) {
2940 jint unloaded_class_index = trap_request_index(trap_request);
2941 const char* reason = trap_reason_name(trap_request_reason(trap_request));
2942 const char* action = trap_action_name(trap_request_action(trap_request));
2943 #if INCLUDE_JVMCI
2944 int debug_id = trap_request_debug_id(trap_request);
2945 #endif
2946 size_t len;
2947 if (unloaded_class_index < 0) {
2948 len = jio_snprintf(buf, buflen, "reason='%s' action='%s'" JVMCI_ONLY(" debug_id='%d'"),
2949 reason, action
2950 #if INCLUDE_JVMCI
2951 ,debug_id
2952 #endif
2953 );
2954 } else {
2955 len = jio_snprintf(buf, buflen, "reason='%s' action='%s' index='%d'" JVMCI_ONLY(" debug_id='%d'"),
2956 reason, action, unloaded_class_index
2957 #if INCLUDE_JVMCI
2958 ,debug_id
2959 #endif
2960 );
2961 }
2962 return buf;
2963 }
2964
2965 juint Deoptimization::_deoptimization_hist
2966 [Deoptimization::Reason_LIMIT]
2967 [1 + Deoptimization::Action_LIMIT]
2968 [Deoptimization::BC_CASE_LIMIT]
2969 = {0};
2970
2971 enum {
2972 LSB_BITS = 8,
2973 LSB_MASK = right_n_bits(LSB_BITS)
2974 };
2975
2976 void Deoptimization::gather_statistics(DeoptReason reason, DeoptAction action,
2977 Bytecodes::Code bc) {
2978 assert(reason >= 0 && reason < Reason_LIMIT, "oob");
2979 assert(action >= 0 && action < Action_LIMIT, "oob");
2980 _deoptimization_hist[Reason_none][0][0] += 1; // total
2981 _deoptimization_hist[reason][0][0] += 1; // per-reason total
2982 juint* cases = _deoptimization_hist[reason][1+action];
2983 juint* bc_counter_addr = nullptr;
2984 juint bc_counter = 0;
2985 // Look for an unused counter, or an exact match to this BC.
2986 if (bc != Bytecodes::_illegal) {
2987 for (int bc_case = 0; bc_case < BC_CASE_LIMIT; bc_case++) {
2988 juint* counter_addr = &cases[bc_case];
2989 juint counter = *counter_addr;
2990 if ((counter == 0 && bc_counter_addr == nullptr)
2991 || (Bytecodes::Code)(counter & LSB_MASK) == bc) {
2992 // this counter is either free or is already devoted to this BC
2993 bc_counter_addr = counter_addr;
2994 bc_counter = counter | bc;
2995 }
2996 }
2997 }
2998 if (bc_counter_addr == nullptr) {
2999 // Overflow, or no given bytecode.
3000 bc_counter_addr = &cases[BC_CASE_LIMIT-1];
3001 bc_counter = (*bc_counter_addr & ~LSB_MASK); // clear LSB
3002 }
3003 *bc_counter_addr = bc_counter + (1 << LSB_BITS);
3004 }
3005
3006 jint Deoptimization::total_deoptimization_count() {
3007 return _deoptimization_hist[Reason_none][0][0];
3008 }
3009
3010 // Get the deopt count for a specific reason and a specific action. If either
3011 // one of 'reason' or 'action' is null, the method returns the sum of all
3012 // deoptimizations with the specific 'action' or 'reason' respectively.
3013 // If both arguments are null, the method returns the total deopt count.
3014 jint Deoptimization::deoptimization_count(const char *reason_str, const char *action_str) {
3015 if (reason_str == nullptr && action_str == nullptr) {
3016 return total_deoptimization_count();
3017 }
3018 juint counter = 0;
3019 for (int reason = 0; reason < Reason_LIMIT; reason++) {
3020 if (reason_str == nullptr || !strcmp(reason_str, trap_reason_name(reason))) {
3021 for (int action = 0; action < Action_LIMIT; action++) {
3022 if (action_str == nullptr || !strcmp(action_str, trap_action_name(action))) {
3023 juint* cases = _deoptimization_hist[reason][1+action];
3024 for (int bc_case = 0; bc_case < BC_CASE_LIMIT; bc_case++) {
3025 counter += cases[bc_case] >> LSB_BITS;
3026 }
3027 }
3028 }
3029 }
3030 }
3031 return counter;
3032 }
3033
3034 void Deoptimization::print_statistics() {
3035 juint total = total_deoptimization_count();
3036 juint account = total;
3037 if (total != 0) {
3038 ttyLocker ttyl;
3039 if (xtty != nullptr) xtty->head("statistics type='deoptimization'");
3040 tty->print_cr("Deoptimization traps recorded:");
3041 #define PRINT_STAT_LINE(name, r) \
3042 tty->print_cr(" %4d (%4.1f%%) %s", (int)(r), ((r) * 100.0) / total, name);
3043 PRINT_STAT_LINE("total", total);
3044 // For each non-zero entry in the histogram, print the reason,
3045 // the action, and (if specifically known) the type of bytecode.
3046 for (int reason = 0; reason < Reason_LIMIT; reason++) {
3047 for (int action = 0; action < Action_LIMIT; action++) {
3048 juint* cases = _deoptimization_hist[reason][1+action];
3049 for (int bc_case = 0; bc_case < BC_CASE_LIMIT; bc_case++) {
3050 juint counter = cases[bc_case];
3051 if (counter != 0) {
3052 char name[1*K];
3053 Bytecodes::Code bc = (Bytecodes::Code)(counter & LSB_MASK);
3054 os::snprintf_checked(name, sizeof(name), "%s/%s/%s",
3055 trap_reason_name(reason),
3056 trap_action_name(action),
3057 Bytecodes::is_defined(bc)? Bytecodes::name(bc): "other");
3058 juint r = counter >> LSB_BITS;
3059 tty->print_cr(" %40s: " UINT32_FORMAT " (%.1f%%)", name, r, (r * 100.0) / total);
3060 account -= r;
3061 }
3062 }
3063 }
3064 }
3065 if (account != 0) {
3066 PRINT_STAT_LINE("unaccounted", account);
3067 }
3068 #undef PRINT_STAT_LINE
3069 if (xtty != nullptr) xtty->tail("statistics");
3070 }
3071 }
3072
3073 #else // COMPILER2_OR_JVMCI
3074
3075
3076 // Stubs for C1 only system.
3077 bool Deoptimization::trap_state_is_recompiled(int trap_state) {
3078 return false;
3079 }
3080
3081 const char* Deoptimization::trap_reason_name(int reason) {
3082 return "unknown";
3083 }
3084
3085 jint Deoptimization::total_deoptimization_count() {
3086 return 0;
3087 }
3088
3089 jint Deoptimization::deoptimization_count(const char *reason_str, const char *action_str) {
3090 return 0;
3091 }
3092
3093 void Deoptimization::print_statistics() {
3094 // no output
3095 }
3096
3097 void
3098 Deoptimization::update_method_data_from_interpreter(MethodData* trap_mdo, int trap_bci, int reason) {
3099 // no update
3100 }
3101
3102 int Deoptimization::trap_state_has_reason(int trap_state, int reason) {
3103 return 0;
3104 }
3105
3106 void Deoptimization::gather_statistics(DeoptReason reason, DeoptAction action,
3107 Bytecodes::Code bc) {
3108 // no update
3109 }
3110
3111 const char* Deoptimization::format_trap_state(char* buf, size_t buflen,
3112 int trap_state) {
3113 jio_snprintf(buf, buflen, "#%d", trap_state);
3114 return buf;
3115 }
3116
3117 #endif // COMPILER2_OR_JVMCI