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/lightweightSynchronizer.hpp"
81 #include "runtime/lockStack.inline.hpp"
82 #include "runtime/objectMonitor.inline.hpp"
83 #include "runtime/osThread.hpp"
84 #include "runtime/safepointVerifiers.hpp"
85 #include "runtime/sharedRuntime.hpp"
86 #include "runtime/signature.hpp"
87 #include "runtime/stackFrameStream.inline.hpp"
88 #include "runtime/stackValue.hpp"
89 #include "runtime/stackWatermarkSet.hpp"
90 #include "runtime/stubRoutines.hpp"
91 #include "runtime/synchronizer.inline.hpp"
92 #include "runtime/threadSMR.hpp"
93 #include "runtime/threadWXSetters.inline.hpp"
94 #include "runtime/vframe.hpp"
95 #include "runtime/vframe_hp.hpp"
96 #include "runtime/vframeArray.hpp"
97 #include "runtime/vmOperations.hpp"
98 #include "utilities/checkedCast.hpp"
99 #include "utilities/events.hpp"
100 #include "utilities/growableArray.hpp"
101 #include "utilities/macros.hpp"
102 #include "utilities/preserveException.hpp"
103 #include "utilities/xmlstream.hpp"
104 #if INCLUDE_JFR
105 #include "jfr/jfr.inline.hpp"
106 #include "jfr/jfrEvents.hpp"
107 #include "jfr/metadata/jfrSerializer.hpp"
108 #endif
109
110 uint64_t DeoptimizationScope::_committed_deopt_gen = 0;
111 uint64_t DeoptimizationScope::_active_deopt_gen = 1;
112 bool DeoptimizationScope::_committing_in_progress = false;
113
114 DeoptimizationScope::DeoptimizationScope() : _required_gen(0) {
115 DEBUG_ONLY(_deopted = false;)
116
117 MutexLocker ml(NMethodState_lock, Mutex::_no_safepoint_check_flag);
118 // If there is nothing to deopt _required_gen is the same as comitted.
119 _required_gen = DeoptimizationScope::_committed_deopt_gen;
120 }
121
122 DeoptimizationScope::~DeoptimizationScope() {
123 assert(_deopted, "Deopt not executed");
124 }
125
126 void DeoptimizationScope::mark(nmethod* nm, bool inc_recompile_counts) {
127 if (!nm->can_be_deoptimized()) {
128 return;
129 }
130
131 ConditionalMutexLocker ml(NMethodState_lock, !NMethodState_lock->owned_by_self(), Mutex::_no_safepoint_check_flag);
132
133 // If it's already marked but we still need it to be deopted.
134 if (nm->is_marked_for_deoptimization()) {
135 dependent(nm);
136 return;
137 }
138
139 nmethod::DeoptimizationStatus status =
140 inc_recompile_counts ? nmethod::deoptimize : nmethod::deoptimize_noupdate;
141 AtomicAccess::store(&nm->_deoptimization_status, status);
142
143 // Make sure active is not committed
144 assert(DeoptimizationScope::_committed_deopt_gen < DeoptimizationScope::_active_deopt_gen, "Must be");
145 assert(nm->_deoptimization_generation == 0, "Is already marked");
146
147 nm->_deoptimization_generation = DeoptimizationScope::_active_deopt_gen;
148 _required_gen = DeoptimizationScope::_active_deopt_gen;
149 }
150
151 void DeoptimizationScope::dependent(nmethod* nm) {
152 ConditionalMutexLocker ml(NMethodState_lock, !NMethodState_lock->owned_by_self(), Mutex::_no_safepoint_check_flag);
153
154 // A method marked by someone else may have a _required_gen lower than what we marked with.
155 // Therefore only store it if it's higher than _required_gen.
156 if (_required_gen < nm->_deoptimization_generation) {
157 _required_gen = nm->_deoptimization_generation;
158 }
159 }
160
161 void DeoptimizationScope::deoptimize_marked() {
162 assert(!_deopted, "Already deopted");
163
164 // We are not alive yet.
165 if (!Universe::is_fully_initialized()) {
166 DEBUG_ONLY(_deopted = true;)
167 return;
168 }
169
170 // Safepoints are a special case, handled here.
171 if (SafepointSynchronize::is_at_safepoint()) {
172 DeoptimizationScope::_committed_deopt_gen = DeoptimizationScope::_active_deopt_gen;
173 DeoptimizationScope::_active_deopt_gen++;
174 Deoptimization::deoptimize_all_marked();
175 DEBUG_ONLY(_deopted = true;)
176 return;
177 }
178
179 uint64_t comitting = 0;
180 bool wait = false;
181 while (true) {
182 {
183 ConditionalMutexLocker ml(NMethodState_lock, !NMethodState_lock->owned_by_self(), Mutex::_no_safepoint_check_flag);
184
185 // First we check if we or someone else already deopted the gen we want.
186 if (DeoptimizationScope::_committed_deopt_gen >= _required_gen) {
187 DEBUG_ONLY(_deopted = true;)
188 return;
189 }
190 if (!_committing_in_progress) {
191 // The version we are about to commit.
192 comitting = DeoptimizationScope::_active_deopt_gen;
193 // Make sure new marks use a higher gen.
194 DeoptimizationScope::_active_deopt_gen++;
195 _committing_in_progress = true;
196 wait = false;
197 } else {
198 // Another thread is handshaking and committing a gen.
199 wait = true;
200 }
201 }
202 if (wait) {
203 // Wait and let the concurrent handshake be performed.
204 ThreadBlockInVM tbivm(JavaThread::current());
205 os::naked_yield();
206 } else {
207 // Performs the handshake.
208 Deoptimization::deoptimize_all_marked(); // May safepoint and an additional deopt may have occurred.
209 DEBUG_ONLY(_deopted = true;)
210 {
211 ConditionalMutexLocker ml(NMethodState_lock, !NMethodState_lock->owned_by_self(), Mutex::_no_safepoint_check_flag);
212
213 // Make sure that committed doesn't go backwards.
214 // Should only happen if we did a deopt during a safepoint above.
215 if (DeoptimizationScope::_committed_deopt_gen < comitting) {
216 DeoptimizationScope::_committed_deopt_gen = comitting;
217 }
218 _committing_in_progress = false;
219
220 assert(DeoptimizationScope::_committed_deopt_gen >= _required_gen, "Must be");
221
222 return;
223 }
224 }
225 }
226 }
227
228 Deoptimization::UnrollBlock::UnrollBlock(int size_of_deoptimized_frame,
229 int caller_adjustment,
230 int caller_actual_parameters,
231 int number_of_frames,
232 intptr_t* frame_sizes,
233 address* frame_pcs,
234 BasicType return_type,
235 int exec_mode) {
236 _size_of_deoptimized_frame = size_of_deoptimized_frame;
237 _caller_adjustment = caller_adjustment;
238 _caller_actual_parameters = caller_actual_parameters;
239 _number_of_frames = number_of_frames;
240 _frame_sizes = frame_sizes;
241 _frame_pcs = frame_pcs;
242 _register_block = NEW_C_HEAP_ARRAY(intptr_t, RegisterMap::reg_count * 2, mtCompiler);
243 _return_type = return_type;
244 _initial_info = 0;
245 // PD (x86 only)
246 _counter_temp = 0;
247 _unpack_kind = exec_mode;
248 _sender_sp_temp = 0;
249
250 _total_frame_sizes = size_of_frames();
251 assert(exec_mode >= 0 && exec_mode < Unpack_LIMIT, "Unexpected exec_mode");
252 }
253
254 Deoptimization::UnrollBlock::~UnrollBlock() {
255 FREE_C_HEAP_ARRAY(intptr_t, _frame_sizes);
256 FREE_C_HEAP_ARRAY(intptr_t, _frame_pcs);
257 FREE_C_HEAP_ARRAY(intptr_t, _register_block);
258 }
259
260 int Deoptimization::UnrollBlock::size_of_frames() const {
261 // Account first for the adjustment of the initial frame
262 intptr_t result = _caller_adjustment;
263 for (int index = 0; index < number_of_frames(); index++) {
264 result += frame_sizes()[index];
265 }
266 return checked_cast<int>(result);
267 }
268
269 void Deoptimization::UnrollBlock::print() {
270 ResourceMark rm;
271 stringStream st;
272 st.print_cr("UnrollBlock");
273 st.print_cr(" size_of_deoptimized_frame = %d", _size_of_deoptimized_frame);
274 st.print( " frame_sizes: ");
275 for (int index = 0; index < number_of_frames(); index++) {
276 st.print("%zd ", frame_sizes()[index]);
277 }
278 st.cr();
279 tty->print_raw(st.freeze());
280 }
281
282 // In order to make fetch_unroll_info work properly with escape
283 // analysis, the method was changed from JRT_LEAF to JRT_BLOCK_ENTRY.
284 // The actual reallocation of previously eliminated objects occurs in realloc_objects,
285 // which is called from the method fetch_unroll_info_helper below.
286 JRT_BLOCK_ENTRY(Deoptimization::UnrollBlock*, Deoptimization::fetch_unroll_info(JavaThread* current, int exec_mode))
287 // fetch_unroll_info() is called at the beginning of the deoptimization
288 // handler. Note this fact before we start generating temporary frames
289 // that can confuse an asynchronous stack walker. This counter is
290 // decremented at the end of unpack_frames().
291 current->inc_in_deopt_handler();
292
293 if (exec_mode == Unpack_exception) {
294 // When we get here, a callee has thrown an exception into a deoptimized
295 // frame. That throw might have deferred stack watermark checking until
296 // after unwinding. So we deal with such deferred requests here.
297 StackWatermarkSet::after_unwind(current);
298 }
299
300 return fetch_unroll_info_helper(current, exec_mode);
301 JRT_END
302
303 #if COMPILER2_OR_JVMCI
304
305 static Klass* get_refined_array_klass(Klass* k, frame* fr, RegisterMap* map, ObjectValue* sv, TRAPS) {
306 // If it's an array, get the properties
307 if (k->is_array_klass() && !k->is_typeArray_klass()) {
308 assert(!k->is_refArray_klass() && !k->is_flatArray_klass(), "Unexpected refined klass");
309 nmethod* nm = fr->cb()->as_nmethod_or_null();
310 if (nm->is_compiled_by_c2()) {
311 assert(sv->has_properties(), "Property information is missing");
312 ArrayKlass::ArrayProperties props = static_cast<ArrayKlass::ArrayProperties>(StackValue::create_stack_value(fr, map, sv->properties())->get_jint());
313 k = ObjArrayKlass::cast(k)->klass_with_properties(props, THREAD);
314 } else {
315 // TODO Graal needs to be fixed. Just go with the default properties for now
316 k = ObjArrayKlass::cast(k)->klass_with_properties(ArrayKlass::ArrayProperties::DEFAULT, THREAD);
317 }
318 }
319 return k;
320 }
321
322 // print information about reallocated objects
323 static void print_objects(JavaThread* deoptee_thread, frame* deoptee, RegisterMap* map,
324 GrowableArray<ScopeValue*>* objects, bool realloc_failures, TRAPS) {
325 ResourceMark rm;
326 stringStream st; // change to logStream with logging
327 st.print_cr("REALLOC OBJECTS in thread " INTPTR_FORMAT, p2i(deoptee_thread));
328 fieldDescriptor fd;
329
330 for (int i = 0; i < objects->length(); i++) {
331 ObjectValue* sv = (ObjectValue*) objects->at(i);
332 Handle obj = sv->value();
333
334 if (obj.is_null()) {
335 st.print_cr(" nullptr");
336 continue;
337 }
338
339 Klass* k = java_lang_Class::as_Klass(sv->klass()->as_ConstantOopReadValue()->value()());
340 k = get_refined_array_klass(k, deoptee, map, sv, THREAD);
341
342 st.print(" object <" INTPTR_FORMAT "> of type ", p2i(sv->value()()));
343 k->print_value_on(&st);
344 st.print_cr(" allocated (%zu bytes)", obj->size() * HeapWordSize);
345
346 if (Verbose && k != nullptr) {
347 k->oop_print_on(obj(), &st);
348 }
349 }
350 tty->print_raw(st.freeze());
351 }
352
353 static bool rematerialize_objects(JavaThread* thread, int exec_mode, nmethod* compiled_method,
354 frame& deoptee, RegisterMap& map, GrowableArray<compiledVFrame*>* chunk,
355 bool& deoptimized_objects) {
356 bool realloc_failures = false;
357 assert (chunk->at(0)->scope() != nullptr,"expect only compiled java frames");
358
359 JavaThread* deoptee_thread = chunk->at(0)->thread();
360 assert(exec_mode == Deoptimization::Unpack_none || (deoptee_thread == thread),
361 "a frame can only be deoptimized by the owner thread");
362
363 GrowableArray<ScopeValue*>* objects = chunk->at(0)->scope()->objects_to_rematerialize(deoptee, map);
364
365 // The flag return_oop() indicates call sites which return oop
366 // in compiled code. Such sites include java method calls,
367 // runtime calls (for example, used to allocate new objects/arrays
368 // on slow code path) and any other calls generated in compiled code.
369 // It is not guaranteed that we can get such information here only
370 // by analyzing bytecode in deoptimized frames. This is why this flag
371 // is set during method compilation (see Compile::Process_OopMap_Node()).
372 // If the previous frame was popped or if we are dispatching an exception,
373 // we don't have an oop result.
374 ScopeDesc* scope = chunk->at(0)->scope();
375 bool save_oop_result = scope->return_oop() && !thread->popframe_forcing_deopt_reexecution() && (exec_mode == Deoptimization::Unpack_deopt);
376 // In case of the return of multiple values, we must take care
377 // of all oop return values.
378 GrowableArray<Handle> return_oops;
379 InlineKlass* vk = nullptr;
380 if (save_oop_result && scope->return_scalarized()) {
381 vk = InlineKlass::returned_inline_klass(map);
382 if (vk != nullptr) {
383 vk->save_oop_fields(map, return_oops);
384 save_oop_result = false;
385 }
386 }
387 if (save_oop_result) {
388 // Reallocation may trigger GC. If deoptimization happened on return from
389 // call which returns oop we need to save it since it is not in oopmap.
390 oop result = deoptee.saved_oop_result(&map);
391 assert(oopDesc::is_oop_or_null(result), "must be oop");
392 return_oops.push(Handle(thread, result));
393 assert(Universe::heap()->is_in_or_null(result), "must be heap pointer");
394 if (TraceDeoptimization) {
395 tty->print_cr("SAVED OOP RESULT " INTPTR_FORMAT " in thread " INTPTR_FORMAT, p2i(result), p2i(thread));
396 tty->cr();
397 }
398 }
399 if (objects != nullptr || vk != nullptr) {
400 if (exec_mode == Deoptimization::Unpack_none) {
401 assert(thread->thread_state() == _thread_in_vm, "assumption");
402 JavaThread* THREAD = thread; // For exception macros.
403 // Clear pending OOM if reallocation fails and return true indicating allocation failure
404 if (vk != nullptr) {
405 realloc_failures = Deoptimization::realloc_inline_type_result(vk, map, return_oops, CHECK_AND_CLEAR_(true));
406 }
407 if (objects != nullptr) {
408 realloc_failures = realloc_failures || Deoptimization::realloc_objects(thread, &deoptee, &map, objects, CHECK_AND_CLEAR_(true));
409 guarantee(compiled_method != nullptr, "deopt must be associated with an nmethod");
410 bool is_jvmci = compiled_method->is_compiled_by_jvmci();
411 Deoptimization::reassign_fields(&deoptee, &map, objects, realloc_failures, is_jvmci, CHECK_AND_CLEAR_(true));
412 }
413 deoptimized_objects = true;
414 } else {
415 JavaThread* current = thread; // For JRT_BLOCK
416 JRT_BLOCK
417 if (vk != nullptr) {
418 realloc_failures = Deoptimization::realloc_inline_type_result(vk, map, return_oops, THREAD);
419 }
420 if (objects != nullptr) {
421 realloc_failures = realloc_failures || Deoptimization::realloc_objects(thread, &deoptee, &map, objects, THREAD);
422 guarantee(compiled_method != nullptr, "deopt must be associated with an nmethod");
423 bool is_jvmci = compiled_method->is_compiled_by_jvmci();
424 Deoptimization::reassign_fields(&deoptee, &map, objects, realloc_failures, is_jvmci, THREAD);
425 }
426 JRT_END
427 }
428 if (TraceDeoptimization && objects != nullptr) {
429 print_objects(deoptee_thread, &deoptee, &map, objects, realloc_failures, thread);
430 }
431 }
432 if (save_oop_result || vk != nullptr) {
433 // Restore result.
434 assert(return_oops.length() == 1, "no inline type");
435 deoptee.set_saved_oop_result(&map, return_oops.pop()());
436 }
437 return realloc_failures;
438 }
439
440 static void restore_eliminated_locks(JavaThread* thread, GrowableArray<compiledVFrame*>* chunk, bool realloc_failures,
441 frame& deoptee, int exec_mode, bool& deoptimized_objects) {
442 JavaThread* deoptee_thread = chunk->at(0)->thread();
443 assert(!EscapeBarrier::objs_are_deoptimized(deoptee_thread, deoptee.id()), "must relock just once");
444 assert(thread == Thread::current(), "should be");
445 HandleMark hm(thread);
446 #ifndef PRODUCT
447 bool first = true;
448 #endif // !PRODUCT
449 // Start locking from outermost/oldest frame
450 for (int i = (chunk->length() - 1); i >= 0; i--) {
451 compiledVFrame* cvf = chunk->at(i);
452 assert (cvf->scope() != nullptr,"expect only compiled java frames");
453 GrowableArray<MonitorInfo*>* monitors = cvf->monitors();
454 if (monitors->is_nonempty()) {
455 bool relocked = Deoptimization::relock_objects(thread, monitors, deoptee_thread, deoptee,
456 exec_mode, realloc_failures);
457 deoptimized_objects = deoptimized_objects || relocked;
458 #ifndef PRODUCT
459 if (PrintDeoptimizationDetails) {
460 ResourceMark rm;
461 stringStream st;
462 for (int j = 0; j < monitors->length(); j++) {
463 MonitorInfo* mi = monitors->at(j);
464 if (mi->eliminated()) {
465 if (first) {
466 first = false;
467 st.print_cr("RELOCK OBJECTS in thread " INTPTR_FORMAT, p2i(thread));
468 }
469 if (exec_mode == Deoptimization::Unpack_none) {
470 ObjectMonitor* monitor = deoptee_thread->current_waiting_monitor();
471 if (monitor != nullptr && monitor->object() == mi->owner()) {
472 st.print_cr(" object <" INTPTR_FORMAT "> DEFERRED relocking after wait", p2i(mi->owner()));
473 continue;
474 }
475 }
476 if (mi->owner_is_scalar_replaced()) {
477 Klass* k = java_lang_Class::as_Klass(mi->owner_klass());
478 st.print_cr(" failed reallocation for klass %s", k->external_name());
479 } else {
480 st.print_cr(" object <" INTPTR_FORMAT "> locked", p2i(mi->owner()));
481 }
482 }
483 }
484 tty->print_raw(st.freeze());
485 }
486 #endif // !PRODUCT
487 }
488 }
489 }
490
491 // Deoptimize objects, that is reallocate and relock them, just before they escape through JVMTI.
492 // The given vframes cover one physical frame.
493 bool Deoptimization::deoptimize_objects_internal(JavaThread* thread, GrowableArray<compiledVFrame*>* chunk,
494 bool& realloc_failures) {
495 frame deoptee = chunk->at(0)->fr();
496 JavaThread* deoptee_thread = chunk->at(0)->thread();
497 nmethod* nm = deoptee.cb()->as_nmethod_or_null();
498 RegisterMap map(chunk->at(0)->register_map());
499 bool deoptimized_objects = false;
500
501 bool const jvmci_enabled = JVMCI_ONLY(EnableJVMCI) NOT_JVMCI(false);
502
503 // Reallocate the non-escaping objects and restore their fields.
504 if (jvmci_enabled COMPILER2_PRESENT(|| (DoEscapeAnalysis && EliminateAllocations)
505 || EliminateAutoBox || EnableVectorAggressiveReboxing)) {
506 realloc_failures = rematerialize_objects(thread, Unpack_none, nm, deoptee, map, chunk, deoptimized_objects);
507 }
508
509 // MonitorInfo structures used in eliminate_locks are not GC safe.
510 NoSafepointVerifier no_safepoint;
511
512 // Now relock objects if synchronization on them was eliminated.
513 if (jvmci_enabled COMPILER2_PRESENT(|| ((DoEscapeAnalysis || EliminateNestedLocks) && EliminateLocks))) {
514 restore_eliminated_locks(thread, chunk, realloc_failures, deoptee, Unpack_none, deoptimized_objects);
515 }
516 return deoptimized_objects;
517 }
518 #endif // COMPILER2_OR_JVMCI
519
520 // This is factored, since it is both called from a JRT_LEAF (deoptimization) and a JRT_ENTRY (uncommon_trap)
521 Deoptimization::UnrollBlock* Deoptimization::fetch_unroll_info_helper(JavaThread* current, int exec_mode) {
522 JFR_ONLY(Jfr::check_and_process_sample_request(current);)
523 // When we get here we are about to unwind the deoptee frame. In order to
524 // catch not yet safe to use frames, the following stack watermark barrier
525 // poll will make such frames safe to use.
526 StackWatermarkSet::before_unwind(current);
527
528 // Note: there is a safepoint safety issue here. No matter whether we enter
529 // via vanilla deopt or uncommon trap we MUST NOT stop at a safepoint once
530 // the vframeArray is created.
531 //
532
533 // Allocate our special deoptimization ResourceMark
534 DeoptResourceMark* dmark = new DeoptResourceMark(current);
535 assert(current->deopt_mark() == nullptr, "Pending deopt!");
536 current->set_deopt_mark(dmark);
537
538 frame stub_frame = current->last_frame(); // Makes stack walkable as side effect
539 RegisterMap map(current,
540 RegisterMap::UpdateMap::include,
541 RegisterMap::ProcessFrames::include,
542 RegisterMap::WalkContinuation::skip);
543 RegisterMap dummy_map(current,
544 RegisterMap::UpdateMap::skip,
545 RegisterMap::ProcessFrames::include,
546 RegisterMap::WalkContinuation::skip);
547 // Now get the deoptee with a valid map
548 frame deoptee = stub_frame.sender(&map);
549 if (exec_mode == Unpack_deopt) {
550 assert(deoptee.is_deoptimized_frame(), "frame is not marked for deoptimization");
551 }
552 // Set the deoptee nmethod
553 assert(current->deopt_compiled_method() == nullptr, "Pending deopt!");
554 nmethod* nm = deoptee.cb()->as_nmethod_or_null();
555 current->set_deopt_compiled_method(nm);
556
557 if (VerifyStack) {
558 current->validate_frame_layout();
559 }
560
561 // Create a growable array of VFrames where each VFrame represents an inlined
562 // Java frame. This storage is allocated with the usual system arena.
563 assert(deoptee.is_compiled_frame(), "Wrong frame type");
564 GrowableArray<compiledVFrame*>* chunk = new GrowableArray<compiledVFrame*>(10);
565 vframe* vf = vframe::new_vframe(&deoptee, &map, current);
566 while (!vf->is_top()) {
567 assert(vf->is_compiled_frame(), "Wrong frame type");
568 chunk->push(compiledVFrame::cast(vf));
569 vf = vf->sender();
570 }
571 assert(vf->is_compiled_frame(), "Wrong frame type");
572 chunk->push(compiledVFrame::cast(vf));
573
574 bool realloc_failures = false;
575
576 #if COMPILER2_OR_JVMCI
577 bool const jvmci_enabled = JVMCI_ONLY(EnableJVMCI) NOT_JVMCI(false);
578
579 // Reallocate the non-escaping objects and restore their fields. Then
580 // relock objects if synchronization on them was eliminated.
581 if (jvmci_enabled COMPILER2_PRESENT( || (DoEscapeAnalysis && EliminateAllocations)
582 || EliminateAutoBox || EnableVectorAggressiveReboxing )) {
583 bool unused;
584 realloc_failures = rematerialize_objects(current, exec_mode, nm, deoptee, map, chunk, unused);
585 }
586 #endif // COMPILER2_OR_JVMCI
587
588 // Ensure that no safepoint is taken after pointers have been stored
589 // in fields of rematerialized objects. If a safepoint occurs from here on
590 // out the java state residing in the vframeArray will be missed.
591 // Locks may be rebaised in a safepoint.
592 NoSafepointVerifier no_safepoint;
593
594 #if COMPILER2_OR_JVMCI
595 if ((jvmci_enabled COMPILER2_PRESENT( || ((DoEscapeAnalysis || EliminateNestedLocks) && EliminateLocks) ))
596 && !EscapeBarrier::objs_are_deoptimized(current, deoptee.id())) {
597 bool unused = false;
598 restore_eliminated_locks(current, chunk, realloc_failures, deoptee, exec_mode, unused);
599 }
600 #endif // COMPILER2_OR_JVMCI
601
602 ScopeDesc* trap_scope = chunk->at(0)->scope();
603 Handle exceptionObject;
604 if (trap_scope->rethrow_exception()) {
605 #ifndef PRODUCT
606 if (PrintDeoptimizationDetails) {
607 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());
608 }
609 #endif // !PRODUCT
610
611 GrowableArray<ScopeValue*>* expressions = trap_scope->expressions();
612 guarantee(expressions != nullptr && expressions->length() == 1, "should have only exception on stack");
613 guarantee(exec_mode != Unpack_exception, "rethrow_exception set with Unpack_exception");
614 ScopeValue* topOfStack = expressions->top();
615 exceptionObject = StackValue::create_stack_value(&deoptee, &map, topOfStack)->get_obj();
616 guarantee(exceptionObject() != nullptr, "exception oop can not be null");
617 }
618
619 vframeArray* array = create_vframeArray(current, deoptee, &map, chunk, realloc_failures);
620 #if COMPILER2_OR_JVMCI
621 if (realloc_failures) {
622 // This destroys all ScopedValue bindings.
623 current->clear_scopedValueBindings();
624 pop_frames_failed_reallocs(current, array);
625 }
626 #endif
627
628 assert(current->vframe_array_head() == nullptr, "Pending deopt!");
629 current->set_vframe_array_head(array);
630
631 // Now that the vframeArray has been created if we have any deferred local writes
632 // added by jvmti then we can free up that structure as the data is now in the
633 // vframeArray
634
635 JvmtiDeferredUpdates::delete_updates_for_frame(current, array->original().id());
636
637 // Compute the caller frame based on the sender sp of stub_frame and stored frame sizes info.
638 CodeBlob* cb = stub_frame.cb();
639 // Verify we have the right vframeArray
640 assert(cb->frame_size() >= 0, "Unexpected frame size");
641 intptr_t* unpack_sp = stub_frame.sp() + cb->frame_size();
642 assert(unpack_sp == deoptee.unextended_sp(), "must be");
643
644 #ifdef ASSERT
645 assert(cb->is_deoptimization_stub() ||
646 cb->is_uncommon_trap_stub() ||
647 strcmp("Stub<DeoptimizationStub.deoptimizationHandler>", cb->name()) == 0 ||
648 strcmp("Stub<UncommonTrapStub.uncommonTrapHandler>", cb->name()) == 0,
649 "unexpected code blob: %s", cb->name());
650 #endif
651
652 // This is a guarantee instead of an assert because if vframe doesn't match
653 // we will unpack the wrong deoptimized frame and wind up in strange places
654 // where it will be very difficult to figure out what went wrong. Better
655 // to die an early death here than some very obscure death later when the
656 // trail is cold.
657 guarantee(array->unextended_sp() == unpack_sp, "vframe_array_head must contain the vframeArray to unpack");
658
659 int number_of_frames = array->frames();
660
661 // Compute the vframes' sizes. Note that frame_sizes[] entries are ordered from outermost to innermost
662 // virtual activation, which is the reverse of the elements in the vframes array.
663 intptr_t* frame_sizes = NEW_C_HEAP_ARRAY(intptr_t, number_of_frames, mtCompiler);
664 // +1 because we always have an interpreter return address for the final slot.
665 address* frame_pcs = NEW_C_HEAP_ARRAY(address, number_of_frames + 1, mtCompiler);
666 int popframe_extra_args = 0;
667 // Create an interpreter return address for the stub to use as its return
668 // address so the skeletal frames are perfectly walkable
669 frame_pcs[number_of_frames] = Interpreter::deopt_entry(vtos, 0);
670
671 // PopFrame requires that the preserved incoming arguments from the recently-popped topmost
672 // activation be put back on the expression stack of the caller for reexecution
673 if (JvmtiExport::can_pop_frame() && current->popframe_forcing_deopt_reexecution()) {
674 popframe_extra_args = in_words(current->popframe_preserved_args_size_in_words());
675 }
676
677 // Find the current pc for sender of the deoptee. Since the sender may have been deoptimized
678 // itself since the deoptee vframeArray was created we must get a fresh value of the pc rather
679 // than simply use array->sender.pc(). This requires us to walk the current set of frames
680 //
681 frame deopt_sender = stub_frame.sender(&dummy_map); // First is the deoptee frame
682 deopt_sender = deopt_sender.sender(&dummy_map); // Now deoptee caller
683
684 // It's possible that the number of parameters at the call site is
685 // different than number of arguments in the callee when method
686 // handles are used. If the caller is interpreted get the real
687 // value so that the proper amount of space can be added to it's
688 // frame.
689 bool caller_was_method_handle = false;
690 if (deopt_sender.is_interpreted_frame()) {
691 methodHandle method(current, deopt_sender.interpreter_frame_method());
692 Bytecode_invoke cur(method, deopt_sender.interpreter_frame_bci());
693 if (cur.has_member_arg()) {
694 // This should cover all real-world cases. One exception is a pathological chain of
695 // MH.linkToXXX() linker calls, which only trusted code could do anyway. To handle that case, we
696 // would need to get the size from the resolved method entry. Another exception would
697 // be an invokedynamic with an adapter that is really a MethodHandle linker.
698 caller_was_method_handle = true;
699 }
700 }
701
702 //
703 // frame_sizes/frame_pcs[0] oldest frame (int or c2i)
704 // frame_sizes/frame_pcs[1] next oldest frame (int)
705 // frame_sizes/frame_pcs[n] youngest frame (int)
706 //
707 // Now a pc in frame_pcs is actually the return address to the frame's caller (a frame
708 // owns the space for the return address to it's caller). Confusing ain't it.
709 //
710 // The vframe array can address vframes with indices running from
711 // 0.._frames-1. Index 0 is the youngest frame and _frame - 1 is the oldest (root) frame.
712 // When we create the skeletal frames we need the oldest frame to be in the zero slot
713 // in the frame_sizes/frame_pcs so the assembly code can do a trivial walk.
714 // so things look a little strange in this loop.
715 //
716 int callee_parameters = 0;
717 int callee_locals = 0;
718 for (int index = 0; index < array->frames(); index++ ) {
719 // frame[number_of_frames - 1 ] = on_stack_size(youngest)
720 // frame[number_of_frames - 2 ] = on_stack_size(sender(youngest))
721 // frame[number_of_frames - 3 ] = on_stack_size(sender(sender(youngest)))
722 frame_sizes[number_of_frames - 1 - index] = BytesPerWord * array->element(index)->on_stack_size(callee_parameters,
723 callee_locals,
724 index == 0,
725 popframe_extra_args);
726 // This pc doesn't have to be perfect just good enough to identify the frame
727 // as interpreted so the skeleton frame will be walkable
728 // The correct pc will be set when the skeleton frame is completely filled out
729 // The final pc we store in the loop is wrong and will be overwritten below
730 frame_pcs[number_of_frames - 1 - index ] = Interpreter::deopt_entry(vtos, 0) - frame::pc_return_offset;
731
732 callee_parameters = array->element(index)->method()->size_of_parameters();
733 callee_locals = array->element(index)->method()->max_locals();
734 popframe_extra_args = 0;
735 }
736
737 // Compute whether the root vframe returns a float or double value.
738 BasicType return_type;
739 {
740 methodHandle method(current, array->element(0)->method());
741 Bytecode_invoke invoke = Bytecode_invoke_check(method, array->element(0)->bci());
742 return_type = invoke.is_valid() ? invoke.result_type() : T_ILLEGAL;
743 }
744
745 // Compute information for handling adapters and adjusting the frame size of the caller.
746 int caller_adjustment = 0;
747
748 // Compute the amount the oldest interpreter frame will have to adjust
749 // its caller's stack by. If the caller is a compiled frame then
750 // we pretend that the callee has no parameters so that the
751 // extension counts for the full amount of locals and not just
752 // locals-parms. This is because without a c2i adapter the parm
753 // area as created by the compiled frame will not be usable by
754 // the interpreter. (Depending on the calling convention there
755 // may not even be enough space).
756
757 // QQQ I'd rather see this pushed down into last_frame_adjust
758 // and have it take the sender (aka caller).
759
760 if (!deopt_sender.is_interpreted_frame() || caller_was_method_handle) {
761 caller_adjustment = last_frame_adjust(0, callee_locals);
762 } else if (callee_locals > callee_parameters) {
763 // The caller frame may need extending to accommodate
764 // non-parameter locals of the first unpacked interpreted frame.
765 // Compute that adjustment.
766 caller_adjustment = last_frame_adjust(callee_parameters, callee_locals);
767 }
768
769 // If the sender is deoptimized we must retrieve the address of the handler
770 // since the frame will "magically" show the original pc before the deopt
771 // and we'd undo the deopt.
772
773 frame_pcs[0] = Continuation::is_cont_barrier_frame(deoptee) ? StubRoutines::cont_returnBarrier() : deopt_sender.raw_pc();
774 if (Continuation::is_continuation_enterSpecial(deopt_sender)) {
775 ContinuationEntry::from_frame(deopt_sender)->set_argsize(0);
776 }
777
778 assert(CodeCache::find_blob(frame_pcs[0]) != nullptr, "bad pc");
779
780 #if INCLUDE_JVMCI
781 if (exceptionObject() != nullptr) {
782 current->set_exception_oop(exceptionObject());
783 exec_mode = Unpack_exception;
784 assert(array->element(0)->rethrow_exception(), "must be");
785 }
786 #endif
787
788 if (current->frames_to_pop_failed_realloc() > 0 && exec_mode != Unpack_uncommon_trap) {
789 assert(current->has_pending_exception(), "should have thrown OOME");
790 current->set_exception_oop(current->pending_exception());
791 current->clear_pending_exception();
792 exec_mode = Unpack_exception;
793 }
794
795 #if INCLUDE_JVMCI
796 if (current->frames_to_pop_failed_realloc() > 0) {
797 current->set_pending_monitorenter(false);
798 }
799 #endif
800
801 int caller_actual_parameters = -1; // value not used except for interpreted frames, see below
802 if (deopt_sender.is_interpreted_frame()) {
803 caller_actual_parameters = callee_parameters + (caller_was_method_handle ? 1 : 0);
804 }
805
806 UnrollBlock* info = new UnrollBlock(array->frame_size() * BytesPerWord,
807 caller_adjustment * BytesPerWord,
808 caller_actual_parameters,
809 number_of_frames,
810 frame_sizes,
811 frame_pcs,
812 return_type,
813 exec_mode);
814 // On some platforms, we need a way to pass some platform dependent
815 // information to the unpacking code so the skeletal frames come out
816 // correct (initial fp value, unextended sp, ...)
817 info->set_initial_info((intptr_t) array->sender().initial_deoptimization_info());
818
819 if (array->frames() > 1) {
820 if (VerifyStack && TraceDeoptimization) {
821 tty->print_cr("Deoptimizing method containing inlining");
822 }
823 }
824
825 array->set_unroll_block(info);
826 return info;
827 }
828
829 // Called to cleanup deoptimization data structures in normal case
830 // after unpacking to stack and when stack overflow error occurs
831 void Deoptimization::cleanup_deopt_info(JavaThread *thread,
832 vframeArray *array) {
833
834 // Get array if coming from exception
835 if (array == nullptr) {
836 array = thread->vframe_array_head();
837 }
838 thread->set_vframe_array_head(nullptr);
839
840 // Free the previous UnrollBlock
841 vframeArray* old_array = thread->vframe_array_last();
842 thread->set_vframe_array_last(array);
843
844 if (old_array != nullptr) {
845 UnrollBlock* old_info = old_array->unroll_block();
846 old_array->set_unroll_block(nullptr);
847 delete old_info;
848 delete old_array;
849 }
850
851 // Deallocate any resource creating in this routine and any ResourceObjs allocated
852 // inside the vframeArray (StackValueCollections)
853
854 delete thread->deopt_mark();
855 thread->set_deopt_mark(nullptr);
856 thread->set_deopt_compiled_method(nullptr);
857
858
859 if (JvmtiExport::can_pop_frame()) {
860 // Regardless of whether we entered this routine with the pending
861 // popframe condition bit set, we should always clear it now
862 thread->clear_popframe_condition();
863 }
864
865 // unpack_frames() is called at the end of the deoptimization handler
866 // and (in C2) at the end of the uncommon trap handler. Note this fact
867 // so that an asynchronous stack walker can work again. This counter is
868 // incremented at the beginning of fetch_unroll_info() and (in C2) at
869 // the beginning of uncommon_trap().
870 thread->dec_in_deopt_handler();
871 }
872
873 // Moved from cpu directories because none of the cpus has callee save values.
874 // If a cpu implements callee save values, move this to deoptimization_<cpu>.cpp.
875 void Deoptimization::unwind_callee_save_values(frame* f, vframeArray* vframe_array) {
876
877 // This code is sort of the equivalent of C2IAdapter::setup_stack_frame back in
878 // the days we had adapter frames. When we deoptimize a situation where a
879 // compiled caller calls a compiled caller will have registers it expects
880 // to survive the call to the callee. If we deoptimize the callee the only
881 // way we can restore these registers is to have the oldest interpreter
882 // frame that we create restore these values. That is what this routine
883 // will accomplish.
884
885 // At the moment we have modified c2 to not have any callee save registers
886 // so this problem does not exist and this routine is just a place holder.
887
888 assert(f->is_interpreted_frame(), "must be interpreted");
889 }
890
891 #ifndef PRODUCT
892 #ifdef ASSERT
893 // Return true if the execution after the provided bytecode continues at the
894 // next bytecode in the code. This is not the case for gotos, returns, and
895 // throws.
896 static bool falls_through(Bytecodes::Code bc) {
897 switch (bc) {
898 case Bytecodes::_goto:
899 case Bytecodes::_goto_w:
900 case Bytecodes::_athrow:
901 case Bytecodes::_areturn:
902 case Bytecodes::_dreturn:
903 case Bytecodes::_freturn:
904 case Bytecodes::_ireturn:
905 case Bytecodes::_lreturn:
906 case Bytecodes::_jsr:
907 case Bytecodes::_ret:
908 case Bytecodes::_return:
909 case Bytecodes::_lookupswitch:
910 case Bytecodes::_tableswitch:
911 return false;
912 default:
913 return true;
914 }
915 }
916 #endif
917 #endif
918
919 // Return BasicType of value being returned
920 JRT_LEAF(BasicType, Deoptimization::unpack_frames(JavaThread* thread, int exec_mode))
921 assert(thread == JavaThread::current(), "pre-condition");
922
923 // We are already active in the special DeoptResourceMark any ResourceObj's we
924 // allocate will be freed at the end of the routine.
925
926 // JRT_LEAF methods don't normally allocate handles and there is a
927 // NoHandleMark to enforce that. It is actually safe to use Handles
928 // in a JRT_LEAF method, and sometimes desirable, but to do so we
929 // must use ResetNoHandleMark to bypass the NoHandleMark, and
930 // then use a HandleMark to ensure any Handles we do create are
931 // cleaned up in this scope.
932 ResetNoHandleMark rnhm;
933 HandleMark hm(thread);
934
935 frame stub_frame = thread->last_frame();
936
937 Continuation::notify_deopt(thread, stub_frame.sp());
938
939 // Since the frame to unpack is the top frame of this thread, the vframe_array_head
940 // must point to the vframeArray for the unpack frame.
941 vframeArray* array = thread->vframe_array_head();
942 UnrollBlock* info = array->unroll_block();
943
944 // We set the last_Java frame. But the stack isn't really parsable here. So we
945 // clear it to make sure JFR understands not to try and walk stacks from events
946 // in here.
947 intptr_t* sp = thread->frame_anchor()->last_Java_sp();
948 thread->frame_anchor()->set_last_Java_sp(nullptr);
949
950 // Unpack the interpreter frames and any adapter frame (c2 only) we might create.
951 array->unpack_to_stack(stub_frame, exec_mode, info->caller_actual_parameters());
952
953 thread->frame_anchor()->set_last_Java_sp(sp);
954
955 BasicType bt = info->return_type();
956
957 // If we have an exception pending, claim that the return type is an oop
958 // so the deopt_blob does not overwrite the exception_oop.
959
960 if (exec_mode == Unpack_exception)
961 bt = T_OBJECT;
962
963 // Cleanup thread deopt data
964 cleanup_deopt_info(thread, array);
965
966 #ifndef PRODUCT
967 if (VerifyStack) {
968 ResourceMark res_mark;
969 // Clear pending exception to not break verification code (restored afterwards)
970 PreserveExceptionMark pm(thread);
971
972 thread->validate_frame_layout();
973
974 // Verify that the just-unpacked frames match the interpreter's
975 // notions of expression stack and locals
976 vframeArray* cur_array = thread->vframe_array_last();
977 RegisterMap rm(thread,
978 RegisterMap::UpdateMap::skip,
979 RegisterMap::ProcessFrames::include,
980 RegisterMap::WalkContinuation::skip);
981 rm.set_include_argument_oops(false);
982 int callee_size_of_parameters = 0;
983 for (int frame_idx = 0; frame_idx < cur_array->frames(); frame_idx++) {
984 bool is_top_frame = (frame_idx == 0);
985 vframeArrayElement* el = cur_array->element(frame_idx);
986 frame* iframe = el->iframe();
987 guarantee(iframe->is_interpreted_frame(), "Wrong frame type");
988 methodHandle mh(thread, iframe->interpreter_frame_method());
989 bool reexecute = el->should_reexecute();
990
991 int cur_invoke_parameter_size = 0;
992 int top_frame_expression_stack_adjustment = 0;
993 int max_bci = mh->code_size();
994 BytecodeStream str(mh, iframe->interpreter_frame_bci());
995 assert(str.bci() < max_bci, "bci in interpreter frame out of bounds");
996 Bytecodes::Code cur_code = str.next();
997
998 if (!reexecute && !Bytecodes::is_invoke(cur_code)) {
999 // We can only compute OopMaps for the before state, so we need to roll forward
1000 // to the next bytecode.
1001 assert(is_top_frame, "must be");
1002 assert(falls_through(cur_code), "must be");
1003 assert(cur_code != Bytecodes::_illegal, "illegal bytecode");
1004 assert(str.bci() < max_bci, "bci in interpreter frame out of bounds");
1005
1006 // Need to subtract off the size of the result type of
1007 // the bytecode because this is not described in the
1008 // debug info but returned to the interpreter in the TOS
1009 // caching register
1010 BasicType bytecode_result_type = Bytecodes::result_type(cur_code);
1011 if (bytecode_result_type != T_ILLEGAL) {
1012 top_frame_expression_stack_adjustment = type2size[bytecode_result_type];
1013 }
1014 assert(top_frame_expression_stack_adjustment >= 0, "stack adjustment must be positive");
1015
1016 cur_code = str.next();
1017 // Reflect the fact that we have rolled forward and now need
1018 // top_frame_expression_stack_adjustment
1019 reexecute = true;
1020 }
1021
1022 assert(cur_code != Bytecodes::_illegal, "illegal bytecode");
1023 assert(str.bci() < max_bci, "bci in interpreter frame out of bounds");
1024
1025 // Get the oop map for this bci
1026 InterpreterOopMap mask;
1027 OopMapCache::compute_one_oop_map(mh, str.bci(), &mask);
1028 // Check to see if we can grab the number of outgoing arguments
1029 // at an uncommon trap for an invoke (where the compiler
1030 // generates debug info before the invoke has executed)
1031 if (Bytecodes::is_invoke(cur_code)) {
1032 Bytecode_invoke invoke(mh, str.bci());
1033 cur_invoke_parameter_size = invoke.size_of_parameters();
1034 if (!is_top_frame && invoke.has_member_arg()) {
1035 callee_size_of_parameters++;
1036 }
1037 }
1038
1039 // Verify stack depth and oops in frame
1040 auto match = [&]() {
1041 int iframe_expr_ssize = iframe->interpreter_frame_expression_stack_size();
1042 #if INCLUDE_JVMCI
1043 if (is_top_frame && el->rethrow_exception()) {
1044 return iframe_expr_ssize == 1;
1045 }
1046 #endif
1047 // This should only be needed for C1
1048 if (is_top_frame && exec_mode == Unpack_exception && iframe_expr_ssize == 0) {
1049 return true;
1050 }
1051 if (reexecute) {
1052 int expr_ssize_before = iframe_expr_ssize + top_frame_expression_stack_adjustment;
1053 int oopmap_expr_invoke_ssize = mask.expression_stack_size() + cur_invoke_parameter_size;
1054 return expr_ssize_before == oopmap_expr_invoke_ssize;
1055 } else {
1056 int oopmap_expr_callee_ssize = mask.expression_stack_size() + callee_size_of_parameters;
1057 return iframe_expr_ssize == oopmap_expr_callee_ssize;
1058 }
1059 };
1060 if (!match()) {
1061 // Print out some information that will help us debug the problem
1062 tty->print_cr("Wrong number of expression stack elements during deoptimization");
1063 tty->print_cr(" Error occurred while verifying frame %d (0..%d, 0 is topmost)", frame_idx, cur_array->frames() - 1);
1064 tty->print_cr(" Current code %s", Bytecodes::name(cur_code));
1065 tty->print_cr(" Fabricated interpreter frame had %d expression stack elements",
1066 iframe->interpreter_frame_expression_stack_size());
1067 tty->print_cr(" Interpreter oop map had %d expression stack elements", mask.expression_stack_size());
1068 tty->print_cr(" callee_size_of_parameters = %d", callee_size_of_parameters);
1069 tty->print_cr(" top_frame_expression_stack_adjustment = %d", top_frame_expression_stack_adjustment);
1070 tty->print_cr(" exec_mode = %d", exec_mode);
1071 tty->print_cr(" original should_reexecute = %s", el->should_reexecute() ? "true" : "false");
1072 tty->print_cr(" reexecute = %s%s", reexecute ? "true" : "false",
1073 (reexecute != el->should_reexecute()) ? " (changed)" : "");
1074 #if INCLUDE_JVMCI
1075 tty->print_cr(" rethrow_exception = %s", el->rethrow_exception() ? "true" : "false");
1076 #endif
1077 tty->print_cr(" cur_invoke_parameter_size = %d", cur_invoke_parameter_size);
1078 tty->print_cr(" Thread = " INTPTR_FORMAT ", thread ID = %d", p2i(thread), thread->osthread()->thread_id());
1079 tty->print_cr(" Interpreted frames:");
1080 for (int k = 0; k < cur_array->frames(); k++) {
1081 vframeArrayElement* el = cur_array->element(k);
1082 tty->print_cr(" %s (bci %d)", el->method()->name_and_sig_as_C_string(), el->bci());
1083 }
1084 cur_array->print_on_2(tty);
1085 guarantee(false, "wrong number of expression stack elements during deopt");
1086 }
1087 VerifyOopClosure verify;
1088 iframe->oops_interpreted_do(&verify, &rm, false);
1089 callee_size_of_parameters = mh->size_of_parameters();
1090 }
1091 }
1092 #endif // !PRODUCT
1093
1094 return bt;
1095 JRT_END
1096
1097 class DeoptimizeMarkedHandshakeClosure : public HandshakeClosure {
1098 public:
1099 DeoptimizeMarkedHandshakeClosure() : HandshakeClosure("Deoptimize") {}
1100 void do_thread(Thread* thread) {
1101 JavaThread* jt = JavaThread::cast(thread);
1102 jt->deoptimize_marked_methods();
1103 }
1104 };
1105
1106 void Deoptimization::deoptimize_all_marked() {
1107 ResourceMark rm;
1108
1109 // Make the dependent methods not entrant
1110 CodeCache::make_marked_nmethods_deoptimized();
1111
1112 DeoptimizeMarkedHandshakeClosure deopt;
1113 if (SafepointSynchronize::is_at_safepoint()) {
1114 Threads::java_threads_do(&deopt);
1115 } else {
1116 Handshake::execute(&deopt);
1117 }
1118 }
1119
1120 Deoptimization::DeoptAction Deoptimization::_unloaded_action
1121 = Deoptimization::Action_reinterpret;
1122
1123 #if INCLUDE_JVMCI
1124 template<typename CacheType>
1125 class BoxCacheBase : public CHeapObj<mtCompiler> {
1126 protected:
1127 static InstanceKlass* find_cache_klass(Thread* thread, Symbol* klass_name) {
1128 ResourceMark rm(thread);
1129 char* klass_name_str = klass_name->as_C_string();
1130 InstanceKlass* ik = SystemDictionary::find_instance_klass(thread, klass_name, Handle());
1131 guarantee(ik != nullptr, "%s must be loaded", klass_name_str);
1132 if (!ik->is_in_error_state()) {
1133 guarantee(ik->is_initialized(), "%s must be initialized", klass_name_str);
1134 CacheType::compute_offsets(ik);
1135 }
1136 return ik;
1137 }
1138 };
1139
1140 template<typename PrimitiveType, typename CacheType, typename BoxType> class BoxCache : public BoxCacheBase<CacheType> {
1141 PrimitiveType _low;
1142 PrimitiveType _high;
1143 jobject _cache;
1144 protected:
1145 static BoxCache<PrimitiveType, CacheType, BoxType> *_singleton;
1146 BoxCache(Thread* thread) {
1147 InstanceKlass* ik = BoxCacheBase<CacheType>::find_cache_klass(thread, CacheType::symbol());
1148 if (ik->is_in_error_state()) {
1149 _low = 1;
1150 _high = 0;
1151 _cache = nullptr;
1152 } else {
1153 objArrayOop cache = CacheType::cache(ik);
1154 assert(cache->length() > 0, "Empty cache");
1155 _low = BoxType::value(cache->obj_at(0));
1156 _high = checked_cast<PrimitiveType>(_low + cache->length() - 1);
1157 _cache = JNIHandles::make_global(Handle(thread, cache));
1158 }
1159 }
1160 ~BoxCache() {
1161 JNIHandles::destroy_global(_cache);
1162 }
1163 public:
1164 static BoxCache<PrimitiveType, CacheType, BoxType>* singleton(Thread* thread) {
1165 if (_singleton == nullptr) {
1166 BoxCache<PrimitiveType, CacheType, BoxType>* s = new BoxCache<PrimitiveType, CacheType, BoxType>(thread);
1167 if (!AtomicAccess::replace_if_null(&_singleton, s)) {
1168 delete s;
1169 }
1170 }
1171 return _singleton;
1172 }
1173 oop lookup(PrimitiveType value) {
1174 if (_low <= value && value <= _high) {
1175 int offset = checked_cast<int>(value - _low);
1176 return objArrayOop(JNIHandles::resolve_non_null(_cache))->obj_at(offset);
1177 }
1178 return nullptr;
1179 }
1180 oop lookup_raw(intptr_t raw_value, bool& cache_init_error) {
1181 if (_cache == nullptr) {
1182 cache_init_error = true;
1183 return nullptr;
1184 }
1185 // Have to cast to avoid little/big-endian problems.
1186 if (sizeof(PrimitiveType) > sizeof(jint)) {
1187 jlong value = (jlong)raw_value;
1188 return lookup(value);
1189 }
1190 PrimitiveType value = (PrimitiveType)*((jint*)&raw_value);
1191 return lookup(value);
1192 }
1193 };
1194
1195 typedef BoxCache<jint, java_lang_Integer_IntegerCache, java_lang_Integer> IntegerBoxCache;
1196 typedef BoxCache<jlong, java_lang_Long_LongCache, java_lang_Long> LongBoxCache;
1197 typedef BoxCache<jchar, java_lang_Character_CharacterCache, java_lang_Character> CharacterBoxCache;
1198 typedef BoxCache<jshort, java_lang_Short_ShortCache, java_lang_Short> ShortBoxCache;
1199 typedef BoxCache<jbyte, java_lang_Byte_ByteCache, java_lang_Byte> ByteBoxCache;
1200
1201 template<> BoxCache<jint, java_lang_Integer_IntegerCache, java_lang_Integer>* BoxCache<jint, java_lang_Integer_IntegerCache, java_lang_Integer>::_singleton = nullptr;
1202 template<> BoxCache<jlong, java_lang_Long_LongCache, java_lang_Long>* BoxCache<jlong, java_lang_Long_LongCache, java_lang_Long>::_singleton = nullptr;
1203 template<> BoxCache<jchar, java_lang_Character_CharacterCache, java_lang_Character>* BoxCache<jchar, java_lang_Character_CharacterCache, java_lang_Character>::_singleton = nullptr;
1204 template<> BoxCache<jshort, java_lang_Short_ShortCache, java_lang_Short>* BoxCache<jshort, java_lang_Short_ShortCache, java_lang_Short>::_singleton = nullptr;
1205 template<> BoxCache<jbyte, java_lang_Byte_ByteCache, java_lang_Byte>* BoxCache<jbyte, java_lang_Byte_ByteCache, java_lang_Byte>::_singleton = nullptr;
1206
1207 class BooleanBoxCache : public BoxCacheBase<java_lang_Boolean> {
1208 jobject _true_cache;
1209 jobject _false_cache;
1210 protected:
1211 static BooleanBoxCache *_singleton;
1212 BooleanBoxCache(Thread *thread) {
1213 InstanceKlass* ik = find_cache_klass(thread, java_lang_Boolean::symbol());
1214 if (ik->is_in_error_state()) {
1215 _true_cache = nullptr;
1216 _false_cache = nullptr;
1217 } else {
1218 _true_cache = JNIHandles::make_global(Handle(thread, java_lang_Boolean::get_TRUE(ik)));
1219 _false_cache = JNIHandles::make_global(Handle(thread, java_lang_Boolean::get_FALSE(ik)));
1220 }
1221 }
1222 ~BooleanBoxCache() {
1223 JNIHandles::destroy_global(_true_cache);
1224 JNIHandles::destroy_global(_false_cache);
1225 }
1226 public:
1227 static BooleanBoxCache* singleton(Thread* thread) {
1228 if (_singleton == nullptr) {
1229 BooleanBoxCache* s = new BooleanBoxCache(thread);
1230 if (!AtomicAccess::replace_if_null(&_singleton, s)) {
1231 delete s;
1232 }
1233 }
1234 return _singleton;
1235 }
1236 oop lookup_raw(intptr_t raw_value, bool& cache_in_error) {
1237 if (_true_cache == nullptr) {
1238 cache_in_error = true;
1239 return nullptr;
1240 }
1241 // Have to cast to avoid little/big-endian problems.
1242 jboolean value = (jboolean)*((jint*)&raw_value);
1243 return lookup(value);
1244 }
1245 oop lookup(jboolean value) {
1246 if (value != 0) {
1247 return JNIHandles::resolve_non_null(_true_cache);
1248 }
1249 return JNIHandles::resolve_non_null(_false_cache);
1250 }
1251 };
1252
1253 BooleanBoxCache* BooleanBoxCache::_singleton = nullptr;
1254
1255 oop Deoptimization::get_cached_box(AutoBoxObjectValue* bv, frame* fr, RegisterMap* reg_map, bool& cache_init_error, TRAPS) {
1256 Klass* k = java_lang_Class::as_Klass(bv->klass()->as_ConstantOopReadValue()->value()());
1257 BasicType box_type = vmClasses::box_klass_type(k);
1258 if (box_type != T_OBJECT) {
1259 StackValue* value = StackValue::create_stack_value(fr, reg_map, bv->field_at(box_type == T_LONG ? 1 : 0));
1260 switch(box_type) {
1261 case T_INT: return IntegerBoxCache::singleton(THREAD)->lookup_raw(value->get_intptr(), cache_init_error);
1262 case T_CHAR: return CharacterBoxCache::singleton(THREAD)->lookup_raw(value->get_intptr(), cache_init_error);
1263 case T_SHORT: return ShortBoxCache::singleton(THREAD)->lookup_raw(value->get_intptr(), cache_init_error);
1264 case T_BYTE: return ByteBoxCache::singleton(THREAD)->lookup_raw(value->get_intptr(), cache_init_error);
1265 case T_BOOLEAN: return BooleanBoxCache::singleton(THREAD)->lookup_raw(value->get_intptr(), cache_init_error);
1266 case T_LONG: return LongBoxCache::singleton(THREAD)->lookup_raw(value->get_intptr(), cache_init_error);
1267 default:;
1268 }
1269 }
1270 return nullptr;
1271 }
1272 #endif // INCLUDE_JVMCI
1273
1274 #if COMPILER2_OR_JVMCI
1275 bool Deoptimization::realloc_objects(JavaThread* thread, frame* fr, RegisterMap* reg_map, GrowableArray<ScopeValue*>* objects, TRAPS) {
1276 Handle pending_exception(THREAD, thread->pending_exception());
1277 const char* exception_file = thread->exception_file();
1278 int exception_line = thread->exception_line();
1279 thread->clear_pending_exception();
1280
1281 bool failures = false;
1282
1283 for (int i = 0; i < objects->length(); i++) {
1284 assert(objects->at(i)->is_object(), "invalid debug information");
1285 ObjectValue* sv = (ObjectValue*) objects->at(i);
1286 Klass* k = java_lang_Class::as_Klass(sv->klass()->as_ConstantOopReadValue()->value()());
1287 k = get_refined_array_klass(k, fr, reg_map, sv, THREAD);
1288
1289 // Check if the object may be null and has an additional null_marker input that needs
1290 // to be checked before using the field values. Skip re-allocation if it is null.
1291 if (k->is_inline_klass() && sv->has_properties()) {
1292 jint null_marker = StackValue::create_stack_value(fr, reg_map, sv->properties())->get_jint();
1293 if (null_marker == 0) {
1294 continue;
1295 }
1296 }
1297
1298 oop obj = nullptr;
1299 bool cache_init_error = false;
1300 if (k->is_instance_klass()) {
1301 #if INCLUDE_JVMCI
1302 nmethod* nm = fr->cb()->as_nmethod_or_null();
1303 if (nm->is_compiled_by_jvmci() && sv->is_auto_box()) {
1304 AutoBoxObjectValue* abv = (AutoBoxObjectValue*) sv;
1305 obj = get_cached_box(abv, fr, reg_map, cache_init_error, THREAD);
1306 if (obj != nullptr) {
1307 // Set the flag to indicate the box came from a cache, so that we can skip the field reassignment for it.
1308 abv->set_cached(true);
1309 } else if (cache_init_error) {
1310 // Results in an OOME which is valid (as opposed to a class initialization error)
1311 // and is fine for the rare case a cache initialization failing.
1312 failures = true;
1313 }
1314 }
1315 #endif // INCLUDE_JVMCI
1316
1317 InstanceKlass* ik = InstanceKlass::cast(k);
1318 if (obj == nullptr && !cache_init_error) {
1319 InternalOOMEMark iom(THREAD);
1320 if (EnableVectorSupport && VectorSupport::is_vector(ik)) {
1321 obj = VectorSupport::allocate_vector(ik, fr, reg_map, sv, THREAD);
1322 } else {
1323 obj = ik->allocate_instance(THREAD);
1324 }
1325 }
1326 } else if (k->is_flatArray_klass()) {
1327 FlatArrayKlass* ak = FlatArrayKlass::cast(k);
1328 // Inline type array must be zeroed because not all memory is reassigned
1329 obj = ak->allocate_instance(sv->field_size(), ak->properties(), THREAD);
1330 } else if (k->is_typeArray_klass()) {
1331 TypeArrayKlass* ak = TypeArrayKlass::cast(k);
1332 assert(sv->field_size() % type2size[ak->element_type()] == 0, "non-integral array length");
1333 int len = sv->field_size() / type2size[ak->element_type()];
1334 InternalOOMEMark iom(THREAD);
1335 obj = ak->allocate_instance(len, THREAD);
1336 } else if (k->is_refArray_klass()) {
1337 RefArrayKlass* ak = RefArrayKlass::cast(k);
1338 InternalOOMEMark iom(THREAD);
1339 obj = ak->allocate_instance(sv->field_size(), ak->properties(), THREAD);
1340 }
1341
1342 if (obj == nullptr) {
1343 failures = true;
1344 }
1345
1346 assert(sv->value().is_null(), "redundant reallocation");
1347 assert(obj != nullptr || HAS_PENDING_EXCEPTION || cache_init_error, "allocation should succeed or we should get an exception");
1348 CLEAR_PENDING_EXCEPTION;
1349 sv->set_value(obj);
1350 }
1351
1352 if (failures) {
1353 THROW_OOP_(Universe::out_of_memory_error_realloc_objects(), failures);
1354 } else if (pending_exception.not_null()) {
1355 thread->set_pending_exception(pending_exception(), exception_file, exception_line);
1356 }
1357
1358 return failures;
1359 }
1360
1361 // We're deoptimizing at the return of a call, inline type fields are
1362 // in registers. When we go back to the interpreter, it will expect a
1363 // reference to an inline type instance. Allocate and initialize it from
1364 // the register values here.
1365 bool Deoptimization::realloc_inline_type_result(InlineKlass* vk, const RegisterMap& map, GrowableArray<Handle>& return_oops, TRAPS) {
1366 oop new_vt = vk->realloc_result(map, return_oops, THREAD);
1367 if (new_vt == nullptr) {
1368 CLEAR_PENDING_EXCEPTION;
1369 THROW_OOP_(Universe::out_of_memory_error_realloc_objects(), true);
1370 }
1371 return_oops.clear();
1372 return_oops.push(Handle(THREAD, new_vt));
1373 return false;
1374 }
1375
1376 #if INCLUDE_JVMCI
1377 /**
1378 * For primitive types whose kind gets "erased" at runtime (shorts become stack ints),
1379 * we need to somehow be able to recover the actual kind to be able to write the correct
1380 * amount of bytes.
1381 * For that purpose, this method assumes that, for an entry spanning n bytes at index i,
1382 * the entries at index n + 1 to n + i are 'markers'.
1383 * For example, if we were writing a short at index 4 of a byte array of size 8, the
1384 * expected form of the array would be:
1385 *
1386 * {b0, b1, b2, b3, INT, marker, b6, b7}
1387 *
1388 * Thus, in order to get back the size of the entry, we simply need to count the number
1389 * of marked entries
1390 *
1391 * @param virtualArray the virtualized byte array
1392 * @param i index of the virtual entry we are recovering
1393 * @return The number of bytes the entry spans
1394 */
1395 static int count_number_of_bytes_for_entry(ObjectValue *virtualArray, int i) {
1396 int index = i;
1397 while (++index < virtualArray->field_size() &&
1398 virtualArray->field_at(index)->is_marker()) {}
1399 return index - i;
1400 }
1401
1402 /**
1403 * If there was a guarantee for byte array to always start aligned to a long, we could
1404 * do a simple check on the parity of the index. Unfortunately, that is not always the
1405 * case. Thus, we check alignment of the actual address we are writing to.
1406 * In the unlikely case index 0 is 5-aligned for example, it would then be possible to
1407 * write a long to index 3.
1408 */
1409 static jbyte* check_alignment_get_addr(typeArrayOop obj, int index, int expected_alignment) {
1410 jbyte* res = obj->byte_at_addr(index);
1411 assert((((intptr_t) res) % expected_alignment) == 0, "Non-aligned write");
1412 return res;
1413 }
1414
1415 static void byte_array_put(typeArrayOop obj, StackValue* value, int index, int byte_count) {
1416 switch (byte_count) {
1417 case 1:
1418 obj->byte_at_put(index, (jbyte) value->get_jint());
1419 break;
1420 case 2:
1421 *((jshort *) check_alignment_get_addr(obj, index, 2)) = (jshort) value->get_jint();
1422 break;
1423 case 4:
1424 *((jint *) check_alignment_get_addr(obj, index, 4)) = value->get_jint();
1425 break;
1426 case 8:
1427 *((jlong *) check_alignment_get_addr(obj, index, 8)) = (jlong) value->get_intptr();
1428 break;
1429 default:
1430 ShouldNotReachHere();
1431 }
1432 }
1433 #endif // INCLUDE_JVMCI
1434
1435
1436 // restore elements of an eliminated type array
1437 void Deoptimization::reassign_type_array_elements(frame* fr, RegisterMap* reg_map, ObjectValue* sv, typeArrayOop obj, BasicType type) {
1438 int index = 0;
1439
1440 for (int i = 0; i < sv->field_size(); i++) {
1441 StackValue* value = StackValue::create_stack_value(fr, reg_map, sv->field_at(i));
1442 switch(type) {
1443 case T_LONG: case T_DOUBLE: {
1444 assert(value->type() == T_INT, "Agreement.");
1445 StackValue* low =
1446 StackValue::create_stack_value(fr, reg_map, sv->field_at(++i));
1447 #ifdef _LP64
1448 jlong res = (jlong)low->get_intptr();
1449 #else
1450 jlong res = jlong_from(value->get_jint(), low->get_jint());
1451 #endif
1452 obj->long_at_put(index, res);
1453 break;
1454 }
1455
1456 case T_INT: case T_FLOAT: { // 4 bytes.
1457 assert(value->type() == T_INT, "Agreement.");
1458 #if INCLUDE_JVMCI
1459 // big_value allows encoding double/long value as e.g. [int = 0, long], and storing
1460 // the value in two array elements.
1461 bool big_value = false;
1462 if (i + 1 < sv->field_size() && type == T_INT) {
1463 if (sv->field_at(i)->is_location()) {
1464 Location::Type type = ((LocationValue*) sv->field_at(i))->location().type();
1465 if (type == Location::dbl || type == Location::lng) {
1466 big_value = true;
1467 }
1468 } else if (sv->field_at(i)->is_constant_int()) {
1469 ScopeValue* next_scope_field = sv->field_at(i + 1);
1470 if (next_scope_field->is_constant_long() || next_scope_field->is_constant_double()) {
1471 big_value = true;
1472 }
1473 }
1474 }
1475
1476 if (big_value) {
1477 StackValue* low = StackValue::create_stack_value(fr, reg_map, sv->field_at(++i));
1478 #ifdef _LP64
1479 jlong res = (jlong)low->get_intptr();
1480 #else
1481 jlong res = jlong_from(value->get_jint(), low->get_jint());
1482 #endif
1483 obj->int_at_put(index, *(jint*)&res);
1484 obj->int_at_put(++index, *((jint*)&res + 1));
1485 } else {
1486 obj->int_at_put(index, value->get_jint());
1487 }
1488 #else // not INCLUDE_JVMCI
1489 obj->int_at_put(index, value->get_jint());
1490 #endif // INCLUDE_JVMCI
1491 break;
1492 }
1493
1494 case T_SHORT:
1495 assert(value->type() == T_INT, "Agreement.");
1496 obj->short_at_put(index, (jshort)value->get_jint());
1497 break;
1498
1499 case T_CHAR:
1500 assert(value->type() == T_INT, "Agreement.");
1501 obj->char_at_put(index, (jchar)value->get_jint());
1502 break;
1503
1504 case T_BYTE: {
1505 assert(value->type() == T_INT, "Agreement.");
1506 #if INCLUDE_JVMCI
1507 // The value we get is erased as a regular int. We will need to find its actual byte count 'by hand'.
1508 int byte_count = count_number_of_bytes_for_entry(sv, i);
1509 byte_array_put(obj, value, index, byte_count);
1510 // According to byte_count contract, the values from i + 1 to i + byte_count are illegal values. Skip.
1511 i += byte_count - 1; // Balance the loop counter.
1512 index += byte_count;
1513 // index has been updated so continue at top of loop
1514 continue;
1515 #else
1516 obj->byte_at_put(index, (jbyte)value->get_jint());
1517 break;
1518 #endif // INCLUDE_JVMCI
1519 }
1520
1521 case T_BOOLEAN: {
1522 assert(value->type() == T_INT, "Agreement.");
1523 obj->bool_at_put(index, (jboolean)value->get_jint());
1524 break;
1525 }
1526
1527 default:
1528 ShouldNotReachHere();
1529 }
1530 index++;
1531 }
1532 }
1533
1534 // restore fields of an eliminated object array
1535 void Deoptimization::reassign_object_array_elements(frame* fr, RegisterMap* reg_map, ObjectValue* sv, objArrayOop obj) {
1536 for (int i = 0; i < sv->field_size(); i++) {
1537 StackValue* value = StackValue::create_stack_value(fr, reg_map, sv->field_at(i));
1538 assert(value->type() == T_OBJECT, "object element expected");
1539 obj->obj_at_put(i, value->get_obj()());
1540 }
1541 }
1542
1543 class ReassignedField {
1544 public:
1545 int _offset;
1546 BasicType _type;
1547 InstanceKlass* _klass;
1548 bool _is_flat;
1549 bool _is_null_free;
1550 public:
1551 ReassignedField() : _offset(0), _type(T_ILLEGAL), _klass(nullptr), _is_flat(false), _is_null_free(false) { }
1552 };
1553
1554 // Gets the fields of `klass` that are eliminated by escape analysis and need to be reassigned
1555 static GrowableArray<ReassignedField>* get_reassigned_fields(InstanceKlass* klass, GrowableArray<ReassignedField>* fields, bool is_jvmci) {
1556 InstanceKlass* super = klass->super();
1557 if (super != nullptr) {
1558 get_reassigned_fields(super, fields, is_jvmci);
1559 }
1560 for (AllFieldStream fs(klass); !fs.done(); fs.next()) {
1561 if (!fs.access_flags().is_static() && (is_jvmci || !fs.field_flags().is_injected())) {
1562 ReassignedField field;
1563 field._offset = fs.offset();
1564 field._type = Signature::basic_type(fs.signature());
1565 if (fs.is_flat()) {
1566 field._is_flat = true;
1567 field._is_null_free = fs.is_null_free_inline_type();
1568 // Resolve klass of flat inline type field
1569 field._klass = InlineKlass::cast(klass->get_inline_type_field_klass(fs.index()));
1570 }
1571 fields->append(field);
1572 }
1573 }
1574 return fields;
1575 }
1576
1577 // Restore fields of an eliminated instance object employing the same field order used by the
1578 // compiler when it scalarizes an object at safepoints.
1579 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) {
1580 GrowableArray<ReassignedField>* fields = get_reassigned_fields(klass, new GrowableArray<ReassignedField>(), is_jvmci);
1581 for (int i = 0; i < fields->length(); i++) {
1582 BasicType type = fields->at(i)._type;
1583 int offset = base_offset + fields->at(i)._offset;
1584 // Check for flat inline type field before accessing the ScopeValue because it might not have any fields
1585 if (fields->at(i)._is_flat) {
1586 // Recursively re-assign flat inline type fields
1587 InstanceKlass* vk = fields->at(i)._klass;
1588 assert(vk != nullptr, "must be resolved");
1589 offset -= InlineKlass::cast(vk)->payload_offset(); // Adjust offset to omit oop header
1590 svIndex = reassign_fields_by_klass(vk, fr, reg_map, sv, svIndex, obj, is_jvmci, offset, CHECK_0);
1591 if (!fields->at(i)._is_null_free) {
1592 ScopeValue* scope_field = sv->field_at(svIndex);
1593 StackValue* value = StackValue::create_stack_value(fr, reg_map, scope_field);
1594 int nm_offset = offset + InlineKlass::cast(vk)->null_marker_offset();
1595 obj->bool_field_put(nm_offset, value->get_jint() & 1);
1596 svIndex++;
1597 }
1598 continue; // Continue because we don't need to increment svIndex
1599 }
1600
1601 ScopeValue* scope_field = sv->field_at(svIndex);
1602 StackValue* value = StackValue::create_stack_value(fr, reg_map, scope_field);
1603 switch (type) {
1604 case T_OBJECT:
1605 case T_ARRAY:
1606 assert(value->type() == T_OBJECT, "Agreement.");
1607 obj->obj_field_put(offset, value->get_obj()());
1608 break;
1609
1610 case T_INT: case T_FLOAT: { // 4 bytes.
1611 assert(value->type() == T_INT, "Agreement.");
1612 bool big_value = false;
1613 if (i+1 < fields->length() && fields->at(i+1)._type == T_INT) {
1614 if (scope_field->is_location()) {
1615 Location::Type type = ((LocationValue*) scope_field)->location().type();
1616 if (type == Location::dbl || type == Location::lng) {
1617 big_value = true;
1618 }
1619 }
1620 if (scope_field->is_constant_int()) {
1621 ScopeValue* next_scope_field = sv->field_at(svIndex + 1);
1622 if (next_scope_field->is_constant_long() || next_scope_field->is_constant_double()) {
1623 big_value = true;
1624 }
1625 }
1626 }
1627
1628 if (big_value) {
1629 i++;
1630 assert(i < fields->length(), "second T_INT field needed");
1631 assert(fields->at(i)._type == T_INT, "T_INT field needed");
1632 } else {
1633 obj->int_field_put(offset, value->get_jint());
1634 break;
1635 }
1636 }
1637 /* no break */
1638
1639 case T_LONG: case T_DOUBLE: {
1640 assert(value->type() == T_INT, "Agreement.");
1641 StackValue* low = StackValue::create_stack_value(fr, reg_map, sv->field_at(++svIndex));
1642 #ifdef _LP64
1643 jlong res = (jlong)low->get_intptr();
1644 #else
1645 jlong res = jlong_from(value->get_jint(), low->get_jint());
1646 #endif
1647 obj->long_field_put(offset, res);
1648 break;
1649 }
1650
1651 case T_SHORT:
1652 assert(value->type() == T_INT, "Agreement.");
1653 obj->short_field_put(offset, (jshort)value->get_jint());
1654 break;
1655
1656 case T_CHAR:
1657 assert(value->type() == T_INT, "Agreement.");
1658 obj->char_field_put(offset, (jchar)value->get_jint());
1659 break;
1660
1661 case T_BYTE:
1662 assert(value->type() == T_INT, "Agreement.");
1663 obj->byte_field_put(offset, (jbyte)value->get_jint());
1664 break;
1665
1666 case T_BOOLEAN:
1667 assert(value->type() == T_INT, "Agreement.");
1668 obj->bool_field_put(offset, (jboolean)value->get_jint());
1669 break;
1670
1671 default:
1672 ShouldNotReachHere();
1673 }
1674 svIndex++;
1675 }
1676
1677 return svIndex;
1678 }
1679
1680 // restore fields of an eliminated inline type array
1681 void Deoptimization::reassign_flat_array_elements(frame* fr, RegisterMap* reg_map, ObjectValue* sv, flatArrayOop obj, FlatArrayKlass* vak, bool is_jvmci, TRAPS) {
1682 InlineKlass* vk = vak->element_klass();
1683 assert(vk->maybe_flat_in_array(), "should only be used for flat inline type arrays");
1684 // Adjust offset to omit oop header
1685 int base_offset = arrayOopDesc::base_offset_in_bytes(T_FLAT_ELEMENT) - vk->payload_offset();
1686 // Initialize all elements of the flat inline type array
1687 for (int i = 0; i < sv->field_size(); i++) {
1688 ObjectValue* val = sv->field_at(i)->as_ObjectValue();
1689 int offset = base_offset + (i << Klass::layout_helper_log2_element_size(vak->layout_helper()));
1690 reassign_fields_by_klass(vk, fr, reg_map, val, 0, (oop)obj, is_jvmci, offset, CHECK);
1691 if (!obj->is_null_free_array()) {
1692 jboolean null_marker_value;
1693 if (val->has_properties()) {
1694 null_marker_value = StackValue::create_stack_value(fr, reg_map, val->properties())->get_jint() & 1;
1695 } else {
1696 null_marker_value = 1;
1697 }
1698 obj->bool_field_put(offset + vk->null_marker_offset(), null_marker_value);
1699 }
1700 }
1701 }
1702
1703 // restore fields of all eliminated objects and arrays
1704 void Deoptimization::reassign_fields(frame* fr, RegisterMap* reg_map, GrowableArray<ScopeValue*>* objects, bool realloc_failures, bool is_jvmci, TRAPS) {
1705 for (int i = 0; i < objects->length(); i++) {
1706 assert(objects->at(i)->is_object(), "invalid debug information");
1707 ObjectValue* sv = (ObjectValue*) objects->at(i);
1708 Klass* k = java_lang_Class::as_Klass(sv->klass()->as_ConstantOopReadValue()->value()());
1709 k = get_refined_array_klass(k, fr, reg_map, sv, THREAD);
1710
1711 Handle obj = sv->value();
1712 assert(obj.not_null() || realloc_failures || sv->has_properties(), "reallocation was missed");
1713 #ifndef PRODUCT
1714 if (PrintDeoptimizationDetails) {
1715 tty->print_cr("reassign fields for object of type %s!", k->name()->as_C_string());
1716 }
1717 #endif // !PRODUCT
1718
1719 if (obj.is_null()) {
1720 continue;
1721 }
1722
1723 #if INCLUDE_JVMCI
1724 // Don't reassign fields of boxes that came from a cache. Caches may be in CDS.
1725 if (sv->is_auto_box() && ((AutoBoxObjectValue*) sv)->is_cached()) {
1726 continue;
1727 }
1728 #endif // INCLUDE_JVMCI
1729 if (EnableVectorSupport && VectorSupport::is_vector(k)) {
1730 assert(sv->field_size() == 1, "%s not a vector", k->name()->as_C_string());
1731 ScopeValue* payload = sv->field_at(0);
1732 if (payload->is_location() &&
1733 payload->as_LocationValue()->location().type() == Location::vector) {
1734 #ifndef PRODUCT
1735 if (PrintDeoptimizationDetails) {
1736 tty->print_cr("skip field reassignment for this vector - it should be assigned already");
1737 if (Verbose) {
1738 Handle obj = sv->value();
1739 k->oop_print_on(obj(), tty);
1740 }
1741 }
1742 #endif // !PRODUCT
1743 continue; // Such vector's value was already restored in VectorSupport::allocate_vector().
1744 }
1745 // Else fall-through to do assignment for scalar-replaced boxed vector representation
1746 // which could be restored after vector object allocation.
1747 }
1748 if (k->is_instance_klass()) {
1749 InstanceKlass* ik = InstanceKlass::cast(k);
1750 reassign_fields_by_klass(ik, fr, reg_map, sv, 0, obj(), is_jvmci, 0, CHECK);
1751 } else if (k->is_flatArray_klass()) {
1752 FlatArrayKlass* vak = FlatArrayKlass::cast(k);
1753 reassign_flat_array_elements(fr, reg_map, sv, (flatArrayOop) obj(), vak, is_jvmci, CHECK);
1754 } else if (k->is_typeArray_klass()) {
1755 TypeArrayKlass* ak = TypeArrayKlass::cast(k);
1756 reassign_type_array_elements(fr, reg_map, sv, (typeArrayOop) obj(), ak->element_type());
1757 } else if (k->is_refArray_klass()) {
1758 reassign_object_array_elements(fr, reg_map, sv, (objArrayOop) obj());
1759 }
1760 }
1761 // These objects may escape when we return to Interpreter after deoptimization.
1762 // We need barrier so that stores that initialize these objects can't be reordered
1763 // with subsequent stores that make these objects accessible by other threads.
1764 OrderAccess::storestore();
1765 }
1766
1767
1768 // relock objects for which synchronization was eliminated
1769 bool Deoptimization::relock_objects(JavaThread* thread, GrowableArray<MonitorInfo*>* monitors,
1770 JavaThread* deoptee_thread, frame& fr, int exec_mode, bool realloc_failures) {
1771 bool relocked_objects = false;
1772 for (int i = 0; i < monitors->length(); i++) {
1773 MonitorInfo* mon_info = monitors->at(i);
1774 if (mon_info->eliminated()) {
1775 assert(!mon_info->owner_is_scalar_replaced() || realloc_failures, "reallocation was missed");
1776 relocked_objects = true;
1777 if (!mon_info->owner_is_scalar_replaced()) {
1778 Handle obj(thread, mon_info->owner());
1779 markWord mark = obj->mark();
1780 if (exec_mode == Unpack_none) {
1781 if (mark.has_monitor()) {
1782 // defer relocking if the deoptee thread is currently waiting for obj
1783 ObjectMonitor* waiting_monitor = deoptee_thread->current_waiting_monitor();
1784 if (waiting_monitor != nullptr && waiting_monitor->object() == obj()) {
1785 assert(fr.is_deoptimized_frame(), "frame must be scheduled for deoptimization");
1786 if (UseObjectMonitorTable) {
1787 mon_info->lock()->clear_object_monitor_cache();
1788 }
1789 #ifdef ASSERT
1790 else {
1791 assert(!UseObjectMonitorTable, "must be");
1792 mon_info->lock()->set_bad_monitor_deopt();
1793 }
1794 #endif
1795 JvmtiDeferredUpdates::inc_relock_count_after_wait(deoptee_thread);
1796 continue;
1797 }
1798 }
1799 }
1800 BasicLock* lock = mon_info->lock();
1801 // We have lost information about the correct state of the lock stack.
1802 // Entering may create an invalid lock stack. Inflate the lock if it
1803 // was fast_locked to restore the valid lock stack.
1804 if (UseObjectMonitorTable) {
1805 // UseObjectMonitorTable expects the BasicLock cache to be either a
1806 // valid ObjectMonitor* or nullptr. Right now it is garbage, set it
1807 // to nullptr.
1808 lock->clear_object_monitor_cache();
1809 }
1810 ObjectSynchronizer::enter_for(obj, lock, deoptee_thread);
1811 if (deoptee_thread->lock_stack().contains(obj())) {
1812 LightweightSynchronizer::inflate_fast_locked_object(obj(), ObjectSynchronizer::InflateCause::inflate_cause_vm_internal,
1813 deoptee_thread, thread);
1814 }
1815 assert(mon_info->owner()->is_locked(), "object must be locked now");
1816 assert(obj->mark().has_monitor(), "must be");
1817 assert(!deoptee_thread->lock_stack().contains(obj()), "must be");
1818 assert(ObjectSynchronizer::read_monitor(thread, obj(), obj->mark())->has_owner(deoptee_thread), "must be");
1819 }
1820 }
1821 }
1822 return relocked_objects;
1823 }
1824 #endif // COMPILER2_OR_JVMCI
1825
1826 vframeArray* Deoptimization::create_vframeArray(JavaThread* thread, frame fr, RegisterMap *reg_map, GrowableArray<compiledVFrame*>* chunk, bool realloc_failures) {
1827 Events::log_deopt_message(thread, "DEOPT PACKING pc=" INTPTR_FORMAT " sp=" INTPTR_FORMAT, p2i(fr.pc()), p2i(fr.sp()));
1828
1829 // Register map for next frame (used for stack crawl). We capture
1830 // the state of the deopt'ing frame's caller. Thus if we need to
1831 // stuff a C2I adapter we can properly fill in the callee-save
1832 // register locations.
1833 frame caller = fr.sender(reg_map);
1834 int frame_size = pointer_delta_as_int(caller.sp(), fr.sp());
1835
1836 frame sender = caller;
1837
1838 // Since the Java thread being deoptimized will eventually adjust it's own stack,
1839 // the vframeArray containing the unpacking information is allocated in the C heap.
1840 // For Compiler1, the caller of the deoptimized frame is saved for use by unpack_frames().
1841 vframeArray* array = vframeArray::allocate(thread, frame_size, chunk, reg_map, sender, caller, fr, realloc_failures);
1842
1843 // Compare the vframeArray to the collected vframes
1844 assert(array->structural_compare(thread, chunk), "just checking");
1845
1846 if (TraceDeoptimization) {
1847 ResourceMark rm;
1848 stringStream st;
1849 st.print_cr("DEOPT PACKING thread=" INTPTR_FORMAT " vframeArray=" INTPTR_FORMAT, p2i(thread), p2i(array));
1850 st.print(" ");
1851 fr.print_on(&st);
1852 st.print_cr(" Virtual frames (innermost/newest first):");
1853 for (int index = 0; index < chunk->length(); index++) {
1854 compiledVFrame* vf = chunk->at(index);
1855 int bci = vf->raw_bci();
1856 const char* code_name;
1857 if (bci == SynchronizationEntryBCI) {
1858 code_name = "sync entry";
1859 } else {
1860 Bytecodes::Code code = vf->method()->code_at(bci);
1861 code_name = Bytecodes::name(code);
1862 }
1863
1864 st.print(" VFrame %d (" INTPTR_FORMAT ")", index, p2i(vf));
1865 st.print(" - %s", vf->method()->name_and_sig_as_C_string());
1866 st.print(" - %s", code_name);
1867 st.print_cr(" @ bci=%d ", bci);
1868 }
1869 tty->print_raw(st.freeze());
1870 tty->cr();
1871 }
1872
1873 return array;
1874 }
1875
1876 #if COMPILER2_OR_JVMCI
1877 void Deoptimization::pop_frames_failed_reallocs(JavaThread* thread, vframeArray* array) {
1878 // Reallocation of some scalar replaced objects failed. Record
1879 // that we need to pop all the interpreter frames for the
1880 // deoptimized compiled frame.
1881 assert(thread->frames_to_pop_failed_realloc() == 0, "missed frames to pop?");
1882 thread->set_frames_to_pop_failed_realloc(array->frames());
1883 // Unlock all monitors here otherwise the interpreter will see a
1884 // mix of locked and unlocked monitors (because of failed
1885 // reallocations of synchronized objects) and be confused.
1886 for (int i = 0; i < array->frames(); i++) {
1887 MonitorChunk* monitors = array->element(i)->monitors();
1888 if (monitors != nullptr) {
1889 // Unlock in reverse order starting from most nested monitor.
1890 for (int j = (monitors->number_of_monitors() - 1); j >= 0; j--) {
1891 BasicObjectLock* src = monitors->at(j);
1892 if (src->obj() != nullptr) {
1893 ObjectSynchronizer::exit(src->obj(), src->lock(), thread);
1894 }
1895 }
1896 array->element(i)->free_monitors();
1897 #ifdef ASSERT
1898 array->element(i)->set_removed_monitors();
1899 #endif
1900 }
1901 }
1902 }
1903 #endif
1904
1905 void Deoptimization::deoptimize_single_frame(JavaThread* thread, frame fr, Deoptimization::DeoptReason reason) {
1906 assert(fr.can_be_deoptimized(), "checking frame type");
1907
1908 gather_statistics(reason, Action_none, Bytecodes::_illegal);
1909
1910 if (LogCompilation && xtty != nullptr) {
1911 nmethod* nm = fr.cb()->as_nmethod_or_null();
1912 assert(nm != nullptr, "only compiled methods can deopt");
1913
1914 ttyLocker ttyl;
1915 xtty->begin_head("deoptimized thread='%zu' reason='%s' pc='" INTPTR_FORMAT "'",(uintx)thread->osthread()->thread_id(), trap_reason_name(reason), p2i(fr.pc()));
1916 nm->log_identity(xtty);
1917 xtty->end_head();
1918 for (ScopeDesc* sd = nm->scope_desc_at(fr.pc()); ; sd = sd->sender()) {
1919 xtty->begin_elem("jvms bci='%d'", sd->bci());
1920 xtty->method(sd->method());
1921 xtty->end_elem();
1922 if (sd->is_top()) break;
1923 }
1924 xtty->tail("deoptimized");
1925 }
1926
1927 Continuation::notify_deopt(thread, fr.sp());
1928
1929 // Patch the compiled method so that when execution returns to it we will
1930 // deopt the execution state and return to the interpreter.
1931 fr.deoptimize(thread);
1932 }
1933
1934 void Deoptimization::deoptimize(JavaThread* thread, frame fr, DeoptReason reason) {
1935 // Deoptimize only if the frame comes from compiled code.
1936 // Do not deoptimize the frame which is already patched
1937 // during the execution of the loops below.
1938 if (!fr.is_compiled_frame() || fr.is_deoptimized_frame()) {
1939 return;
1940 }
1941 ResourceMark rm;
1942 deoptimize_single_frame(thread, fr, reason);
1943 }
1944
1945 address Deoptimization::deoptimize_for_missing_exception_handler(nmethod* nm, bool make_not_entrant) {
1946 // there is no exception handler for this pc => deoptimize
1947 if (make_not_entrant) {
1948 nm->make_not_entrant(nmethod::InvalidationReason::MISSING_EXCEPTION_HANDLER);
1949 }
1950
1951 // Use Deoptimization::deoptimize for all of its side-effects:
1952 // gathering traps statistics, logging...
1953 // it also patches the return pc but we do not care about that
1954 // since we return a continuation to the deopt_blob below.
1955 JavaThread* thread = JavaThread::current();
1956 RegisterMap reg_map(thread,
1957 RegisterMap::UpdateMap::skip,
1958 RegisterMap::ProcessFrames::include,
1959 RegisterMap::WalkContinuation::skip);
1960 frame runtime_frame = thread->last_frame();
1961 frame caller_frame = runtime_frame.sender(®_map);
1962 assert(caller_frame.cb()->as_nmethod_or_null() == nm, "expect top frame compiled method");
1963
1964 Deoptimization::deoptimize(thread, caller_frame, Deoptimization::Reason_not_compiled_exception_handler);
1965
1966 if (!nm->is_compiled_by_jvmci()) {
1967 return SharedRuntime::deopt_blob()->unpack_with_exception_in_tls();
1968 }
1969
1970 #if INCLUDE_JVMCI
1971 // JVMCI support
1972 vframe* vf = vframe::new_vframe(&caller_frame, ®_map, thread);
1973 compiledVFrame* cvf = compiledVFrame::cast(vf);
1974 ScopeDesc* imm_scope = cvf->scope();
1975 MethodData* imm_mdo = get_method_data(thread, methodHandle(thread, imm_scope->method()), true);
1976 if (imm_mdo != nullptr) {
1977 // Lock to read ProfileData, and ensure lock is not broken by a safepoint
1978 MutexLocker ml(imm_mdo->extra_data_lock(), Mutex::_no_safepoint_check_flag);
1979
1980 ProfileData* pdata = imm_mdo->allocate_bci_to_data(imm_scope->bci(), nullptr);
1981 if (pdata != nullptr && pdata->is_BitData()) {
1982 BitData* bit_data = (BitData*) pdata;
1983 bit_data->set_exception_seen();
1984 }
1985 }
1986
1987
1988 MethodData* trap_mdo = get_method_data(thread, methodHandle(thread, nm->method()), true);
1989 if (trap_mdo != nullptr) {
1990 trap_mdo->inc_trap_count(Deoptimization::Reason_not_compiled_exception_handler);
1991 }
1992 #endif
1993
1994 return SharedRuntime::deopt_blob()->unpack_with_exception_in_tls();
1995 }
1996
1997 void Deoptimization::deoptimize_frame_internal(JavaThread* thread, intptr_t* id, DeoptReason reason) {
1998 assert(thread == Thread::current() ||
1999 thread->is_handshake_safe_for(Thread::current()) ||
2000 SafepointSynchronize::is_at_safepoint(),
2001 "can only deoptimize other thread at a safepoint/handshake");
2002 // Compute frame and register map based on thread and sp.
2003 RegisterMap reg_map(thread,
2004 RegisterMap::UpdateMap::skip,
2005 RegisterMap::ProcessFrames::include,
2006 RegisterMap::WalkContinuation::skip);
2007 frame fr = thread->last_frame();
2008 while (fr.id() != id) {
2009 fr = fr.sender(®_map);
2010 }
2011 deoptimize(thread, fr, reason);
2012 }
2013
2014
2015 void Deoptimization::deoptimize_frame(JavaThread* thread, intptr_t* id, DeoptReason reason) {
2016 Thread* current = Thread::current();
2017 if (thread == current || thread->is_handshake_safe_for(current)) {
2018 Deoptimization::deoptimize_frame_internal(thread, id, reason);
2019 } else {
2020 VM_DeoptimizeFrame deopt(thread, id, reason);
2021 VMThread::execute(&deopt);
2022 }
2023 }
2024
2025 void Deoptimization::deoptimize_frame(JavaThread* thread, intptr_t* id) {
2026 deoptimize_frame(thread, id, Reason_constraint);
2027 }
2028
2029 // JVMTI PopFrame support
2030 JRT_LEAF(void, Deoptimization::popframe_preserve_args(JavaThread* thread, int bytes_to_save, void* start_address))
2031 {
2032 assert(thread == JavaThread::current(), "pre-condition");
2033 thread->popframe_preserve_args(in_ByteSize(bytes_to_save), start_address);
2034 }
2035 JRT_END
2036
2037 MethodData*
2038 Deoptimization::get_method_data(JavaThread* thread, const methodHandle& m,
2039 bool create_if_missing) {
2040 JavaThread* THREAD = thread; // For exception macros.
2041 MethodData* mdo = m()->method_data();
2042 if (mdo == nullptr && create_if_missing && !HAS_PENDING_EXCEPTION) {
2043 // Build an MDO. Ignore errors like OutOfMemory;
2044 // that simply means we won't have an MDO to update.
2045 Method::build_profiling_method_data(m, THREAD);
2046 if (HAS_PENDING_EXCEPTION) {
2047 // Only metaspace OOM is expected. No Java code executed.
2048 assert((PENDING_EXCEPTION->is_a(vmClasses::OutOfMemoryError_klass())), "we expect only an OOM error here");
2049 CLEAR_PENDING_EXCEPTION;
2050 }
2051 mdo = m()->method_data();
2052 }
2053 return mdo;
2054 }
2055
2056 #if COMPILER2_OR_JVMCI
2057 void Deoptimization::load_class_by_index(const constantPoolHandle& constant_pool, int index, TRAPS) {
2058 // In case of an unresolved klass entry, load the class.
2059 // This path is exercised from case _ldc in Parse::do_one_bytecode,
2060 // and probably nowhere else.
2061 // Even that case would benefit from simply re-interpreting the
2062 // bytecode, without paying special attention to the class index.
2063 // So this whole "class index" feature should probably be removed.
2064
2065 if (constant_pool->tag_at(index).is_unresolved_klass()) {
2066 Klass* tk = constant_pool->klass_at(index, THREAD);
2067 if (HAS_PENDING_EXCEPTION) {
2068 // Exception happened during classloading. We ignore the exception here, since it
2069 // is going to be rethrown since the current activation is going to be deoptimized and
2070 // the interpreter will re-execute the bytecode.
2071 // Do not clear probable Async Exceptions.
2072 CLEAR_PENDING_NONASYNC_EXCEPTION;
2073 // Class loading called java code which may have caused a stack
2074 // overflow. If the exception was thrown right before the return
2075 // to the runtime the stack is no longer guarded. Reguard the
2076 // stack otherwise if we return to the uncommon trap blob and the
2077 // stack bang causes a stack overflow we crash.
2078 JavaThread* jt = THREAD;
2079 bool guard_pages_enabled = jt->stack_overflow_state()->reguard_stack_if_needed();
2080 assert(guard_pages_enabled, "stack banging in uncommon trap blob may cause crash");
2081 }
2082 return;
2083 }
2084
2085 assert(!constant_pool->tag_at(index).is_symbol(),
2086 "no symbolic names here, please");
2087 }
2088
2089 #if INCLUDE_JFR
2090
2091 class DeoptReasonSerializer : public JfrSerializer {
2092 public:
2093 void serialize(JfrCheckpointWriter& writer) {
2094 writer.write_count((u4)(Deoptimization::Reason_LIMIT + 1)); // + Reason::many (-1)
2095 for (int i = -1; i < Deoptimization::Reason_LIMIT; ++i) {
2096 writer.write_key((u8)i);
2097 writer.write(Deoptimization::trap_reason_name(i));
2098 }
2099 }
2100 };
2101
2102 class DeoptActionSerializer : public JfrSerializer {
2103 public:
2104 void serialize(JfrCheckpointWriter& writer) {
2105 static const u4 nof_actions = Deoptimization::Action_LIMIT;
2106 writer.write_count(nof_actions);
2107 for (u4 i = 0; i < Deoptimization::Action_LIMIT; ++i) {
2108 writer.write_key(i);
2109 writer.write(Deoptimization::trap_action_name((int)i));
2110 }
2111 }
2112 };
2113
2114 static void register_serializers() {
2115 static int critical_section = 0;
2116 if (1 == critical_section || AtomicAccess::cmpxchg(&critical_section, 0, 1) == 1) {
2117 return;
2118 }
2119 JfrSerializer::register_serializer(TYPE_DEOPTIMIZATIONREASON, true, new DeoptReasonSerializer());
2120 JfrSerializer::register_serializer(TYPE_DEOPTIMIZATIONACTION, true, new DeoptActionSerializer());
2121 }
2122
2123 static void post_deoptimization_event(nmethod* nm,
2124 const Method* method,
2125 int trap_bci,
2126 int instruction,
2127 Deoptimization::DeoptReason reason,
2128 Deoptimization::DeoptAction action) {
2129 assert(nm != nullptr, "invariant");
2130 assert(method != nullptr, "invariant");
2131 if (EventDeoptimization::is_enabled()) {
2132 static bool serializers_registered = false;
2133 if (!serializers_registered) {
2134 register_serializers();
2135 serializers_registered = true;
2136 }
2137 EventDeoptimization event;
2138 event.set_compileId(nm->compile_id());
2139 event.set_compiler(nm->compiler_type());
2140 event.set_method(method);
2141 event.set_lineNumber(method->line_number_from_bci(trap_bci));
2142 event.set_bci(trap_bci);
2143 event.set_instruction(instruction);
2144 event.set_reason(reason);
2145 event.set_action(action);
2146 event.commit();
2147 }
2148 }
2149
2150 #endif // INCLUDE_JFR
2151
2152 static void log_deopt(nmethod* nm, Method* tm, intptr_t pc, frame& fr, int trap_bci,
2153 const char* reason_name, const char* reason_action) {
2154 LogTarget(Debug, deoptimization) lt;
2155 if (lt.is_enabled()) {
2156 LogStream ls(lt);
2157 bool is_osr = nm->is_osr_method();
2158 ls.print("cid=%4d %s level=%d",
2159 nm->compile_id(), (is_osr ? "osr" : " "), nm->comp_level());
2160 ls.print(" %s", tm->name_and_sig_as_C_string());
2161 ls.print(" trap_bci=%d ", trap_bci);
2162 if (is_osr) {
2163 ls.print("osr_bci=%d ", nm->osr_entry_bci());
2164 }
2165 ls.print("%s ", reason_name);
2166 ls.print("%s ", reason_action);
2167 ls.print_cr("pc=" INTPTR_FORMAT " relative_pc=" INTPTR_FORMAT,
2168 pc, fr.pc() - nm->code_begin());
2169 }
2170 }
2171
2172 JRT_ENTRY(void, Deoptimization::uncommon_trap_inner(JavaThread* current, jint trap_request)) {
2173 HandleMark hm(current);
2174
2175 // uncommon_trap() is called at the beginning of the uncommon trap
2176 // handler. Note this fact before we start generating temporary frames
2177 // that can confuse an asynchronous stack walker. This counter is
2178 // decremented at the end of unpack_frames().
2179
2180 current->inc_in_deopt_handler();
2181
2182 #if INCLUDE_JVMCI
2183 // JVMCI might need to get an exception from the stack, which in turn requires the register map to be valid
2184 RegisterMap reg_map(current,
2185 RegisterMap::UpdateMap::include,
2186 RegisterMap::ProcessFrames::include,
2187 RegisterMap::WalkContinuation::skip);
2188 #else
2189 RegisterMap reg_map(current,
2190 RegisterMap::UpdateMap::skip,
2191 RegisterMap::ProcessFrames::include,
2192 RegisterMap::WalkContinuation::skip);
2193 #endif
2194 frame stub_frame = current->last_frame();
2195 frame fr = stub_frame.sender(®_map);
2196
2197 // Log a message
2198 Events::log_deopt_message(current, "Uncommon trap: trap_request=" INT32_FORMAT_X_0 " fr.pc=" INTPTR_FORMAT " relative=" INTPTR_FORMAT,
2199 trap_request, p2i(fr.pc()), fr.pc() - fr.cb()->code_begin());
2200
2201 {
2202 ResourceMark rm;
2203
2204 DeoptReason reason = trap_request_reason(trap_request);
2205 DeoptAction action = trap_request_action(trap_request);
2206 #if INCLUDE_JVMCI
2207 int debug_id = trap_request_debug_id(trap_request);
2208 #endif
2209 jint unloaded_class_index = trap_request_index(trap_request); // CP idx or -1
2210
2211 vframe* vf = vframe::new_vframe(&fr, ®_map, current);
2212 compiledVFrame* cvf = compiledVFrame::cast(vf);
2213
2214 nmethod* nm = cvf->code();
2215
2216 ScopeDesc* trap_scope = cvf->scope();
2217
2218 bool is_receiver_constraint_failure = COMPILER2_PRESENT(VerifyReceiverTypes &&) (reason == Deoptimization::Reason_receiver_constraint);
2219
2220 if (is_receiver_constraint_failure) {
2221 tty->print_cr(" bci=%d pc=" INTPTR_FORMAT ", relative_pc=" INTPTR_FORMAT ", method=%s" JVMCI_ONLY(", debug_id=%d"),
2222 trap_scope->bci(), p2i(fr.pc()), fr.pc() - nm->code_begin(), trap_scope->method()->name_and_sig_as_C_string()
2223 JVMCI_ONLY(COMMA debug_id));
2224 }
2225
2226 methodHandle trap_method(current, trap_scope->method());
2227 int trap_bci = trap_scope->bci();
2228 #if INCLUDE_JVMCI
2229 jlong speculation = current->pending_failed_speculation();
2230 if (nm->is_compiled_by_jvmci()) {
2231 nm->update_speculation(current);
2232 } else {
2233 assert(speculation == 0, "There should not be a speculation for methods compiled by non-JVMCI compilers");
2234 }
2235
2236 if (trap_bci == SynchronizationEntryBCI) {
2237 trap_bci = 0;
2238 current->set_pending_monitorenter(true);
2239 }
2240
2241 if (reason == Deoptimization::Reason_transfer_to_interpreter) {
2242 current->set_pending_transfer_to_interpreter(true);
2243 }
2244 #endif
2245
2246 Bytecodes::Code trap_bc = trap_method->java_code_at(trap_bci);
2247 // Record this event in the histogram.
2248 gather_statistics(reason, action, trap_bc);
2249
2250 // Ensure that we can record deopt. history:
2251 bool create_if_missing = ProfileTraps;
2252
2253 methodHandle profiled_method;
2254 #if INCLUDE_JVMCI
2255 if (nm->is_compiled_by_jvmci()) {
2256 profiled_method = methodHandle(current, nm->method());
2257 } else {
2258 profiled_method = trap_method;
2259 }
2260 #else
2261 profiled_method = trap_method;
2262 #endif
2263
2264 MethodData* trap_mdo =
2265 get_method_data(current, profiled_method, create_if_missing);
2266
2267 { // Log Deoptimization event for JFR, UL and event system
2268 Method* tm = trap_method();
2269 const char* reason_name = trap_reason_name(reason);
2270 const char* reason_action = trap_action_name(action);
2271 intptr_t pc = p2i(fr.pc());
2272
2273 JFR_ONLY(post_deoptimization_event(nm, tm, trap_bci, trap_bc, reason, action);)
2274 log_deopt(nm, tm, pc, fr, trap_bci, reason_name, reason_action);
2275 Events::log_deopt_message(current, "Uncommon trap: reason=%s action=%s pc=" INTPTR_FORMAT " method=%s @ %d %s",
2276 reason_name, reason_action, pc,
2277 tm->name_and_sig_as_C_string(), trap_bci, nm->compiler_name());
2278 }
2279
2280 // Print a bunch of diagnostics, if requested.
2281 if (TraceDeoptimization || LogCompilation || is_receiver_constraint_failure) {
2282 ResourceMark rm;
2283
2284 // Lock to read ProfileData, and ensure lock is not broken by a safepoint
2285 // We must do this already now, since we cannot acquire this lock while
2286 // holding the tty lock (lock ordering by rank).
2287 MutexLocker ml(trap_mdo->extra_data_lock(), Mutex::_no_safepoint_check_flag);
2288
2289 ttyLocker ttyl;
2290
2291 char buf[100];
2292 if (xtty != nullptr) {
2293 xtty->begin_head("uncommon_trap thread='%zu' %s",
2294 os::current_thread_id(),
2295 format_trap_request(buf, sizeof(buf), trap_request));
2296 #if INCLUDE_JVMCI
2297 if (speculation != 0) {
2298 xtty->print(" speculation='" JLONG_FORMAT "'", speculation);
2299 }
2300 #endif
2301 nm->log_identity(xtty);
2302 }
2303 Symbol* class_name = nullptr;
2304 bool unresolved = false;
2305 if (unloaded_class_index >= 0) {
2306 constantPoolHandle constants (current, trap_method->constants());
2307 if (constants->tag_at(unloaded_class_index).is_unresolved_klass()) {
2308 class_name = constants->klass_name_at(unloaded_class_index);
2309 unresolved = true;
2310 if (xtty != nullptr)
2311 xtty->print(" unresolved='1'");
2312 } else if (constants->tag_at(unloaded_class_index).is_symbol()) {
2313 class_name = constants->symbol_at(unloaded_class_index);
2314 }
2315 if (xtty != nullptr)
2316 xtty->name(class_name);
2317 }
2318 if (xtty != nullptr && trap_mdo != nullptr && (int)reason < (int)MethodData::_trap_hist_limit) {
2319 // Dump the relevant MDO state.
2320 // This is the deopt count for the current reason, any previous
2321 // reasons or recompiles seen at this point.
2322 int dcnt = trap_mdo->trap_count(reason);
2323 if (dcnt != 0)
2324 xtty->print(" count='%d'", dcnt);
2325
2326 // We need to lock to read the ProfileData. But to keep the locks ordered, we need to
2327 // lock extra_data_lock before the tty lock.
2328 ProfileData* pdata = trap_mdo->bci_to_data(trap_bci);
2329 int dos = (pdata == nullptr)? 0: pdata->trap_state();
2330 if (dos != 0) {
2331 xtty->print(" state='%s'", format_trap_state(buf, sizeof(buf), dos));
2332 if (trap_state_is_recompiled(dos)) {
2333 int recnt2 = trap_mdo->overflow_recompile_count();
2334 if (recnt2 != 0)
2335 xtty->print(" recompiles2='%d'", recnt2);
2336 }
2337 }
2338 }
2339 if (xtty != nullptr) {
2340 xtty->stamp();
2341 xtty->end_head();
2342 }
2343 if (TraceDeoptimization) { // make noise on the tty
2344 stringStream st;
2345 st.print("UNCOMMON TRAP method=%s", trap_scope->method()->name_and_sig_as_C_string());
2346 st.print(" bci=%d pc=" INTPTR_FORMAT ", relative_pc=" INTPTR_FORMAT JVMCI_ONLY(", debug_id=%d"),
2347 trap_scope->bci(), p2i(fr.pc()), fr.pc() - nm->code_begin() JVMCI_ONLY(COMMA debug_id));
2348 st.print(" compiler=%s compile_id=%d", nm->compiler_name(), nm->compile_id());
2349 #if INCLUDE_JVMCI
2350 if (nm->is_compiled_by_jvmci()) {
2351 const char* installed_code_name = nm->jvmci_name();
2352 if (installed_code_name != nullptr) {
2353 st.print(" (JVMCI: installed code name=%s) ", installed_code_name);
2354 }
2355 }
2356 #endif
2357 st.print(" (@" INTPTR_FORMAT ") thread=%zu reason=%s action=%s unloaded_class_index=%d" JVMCI_ONLY(" debug_id=%d"),
2358 p2i(fr.pc()),
2359 os::current_thread_id(),
2360 trap_reason_name(reason),
2361 trap_action_name(action),
2362 unloaded_class_index
2363 #if INCLUDE_JVMCI
2364 , debug_id
2365 #endif
2366 );
2367 if (class_name != nullptr) {
2368 st.print(unresolved ? " unresolved class: " : " symbol: ");
2369 class_name->print_symbol_on(&st);
2370 }
2371 st.cr();
2372 tty->print_raw(st.freeze());
2373 }
2374 if (xtty != nullptr) {
2375 // Log the precise location of the trap.
2376 for (ScopeDesc* sd = trap_scope; ; sd = sd->sender()) {
2377 xtty->begin_elem("jvms bci='%d'", sd->bci());
2378 xtty->method(sd->method());
2379 xtty->end_elem();
2380 if (sd->is_top()) break;
2381 }
2382 xtty->tail("uncommon_trap");
2383 }
2384 }
2385 // (End diagnostic printout.)
2386
2387 if (is_receiver_constraint_failure) {
2388 fatal("missing receiver type check");
2389 }
2390
2391 // Load class if necessary
2392 if (unloaded_class_index >= 0) {
2393 constantPoolHandle constants(current, trap_method->constants());
2394 load_class_by_index(constants, unloaded_class_index, THREAD);
2395 }
2396
2397 // Flush the nmethod if necessary and desirable.
2398 //
2399 // We need to avoid situations where we are re-flushing the nmethod
2400 // because of a hot deoptimization site. Repeated flushes at the same
2401 // point need to be detected by the compiler and avoided. If the compiler
2402 // cannot avoid them (or has a bug and "refuses" to avoid them), this
2403 // module must take measures to avoid an infinite cycle of recompilation
2404 // and deoptimization. There are several such measures:
2405 //
2406 // 1. If a recompilation is ordered a second time at some site X
2407 // and for the same reason R, the action is adjusted to 'reinterpret',
2408 // to give the interpreter time to exercise the method more thoroughly.
2409 // If this happens, the method's overflow_recompile_count is incremented.
2410 //
2411 // 2. If the compiler fails to reduce the deoptimization rate, then
2412 // the method's overflow_recompile_count will begin to exceed the set
2413 // limit PerBytecodeRecompilationCutoff. If this happens, the action
2414 // is adjusted to 'make_not_compilable', and the method is abandoned
2415 // to the interpreter. This is a performance hit for hot methods,
2416 // but is better than a disastrous infinite cycle of recompilations.
2417 // (Actually, only the method containing the site X is abandoned.)
2418 //
2419 // 3. In parallel with the previous measures, if the total number of
2420 // recompilations of a method exceeds the much larger set limit
2421 // PerMethodRecompilationCutoff, the method is abandoned.
2422 // This should only happen if the method is very large and has
2423 // many "lukewarm" deoptimizations. The code which enforces this
2424 // limit is elsewhere (class nmethod, class Method).
2425 //
2426 // Note that the per-BCI 'is_recompiled' bit gives the compiler one chance
2427 // to recompile at each bytecode independently of the per-BCI cutoff.
2428 //
2429 // The decision to update code is up to the compiler, and is encoded
2430 // in the Action_xxx code. If the compiler requests Action_none
2431 // no trap state is changed, no compiled code is changed, and the
2432 // computation suffers along in the interpreter.
2433 //
2434 // The other action codes specify various tactics for decompilation
2435 // and recompilation. Action_maybe_recompile is the loosest, and
2436 // allows the compiled code to stay around until enough traps are seen,
2437 // and until the compiler gets around to recompiling the trapping method.
2438 //
2439 // The other actions cause immediate removal of the present code.
2440
2441 // Traps caused by injected profile shouldn't pollute trap counts.
2442 bool injected_profile_trap = trap_method->has_injected_profile() &&
2443 (reason == Reason_intrinsic || reason == Reason_unreached);
2444
2445 bool update_trap_state = (reason != Reason_tenured) && !injected_profile_trap;
2446 bool make_not_entrant = false;
2447 bool make_not_compilable = false;
2448 bool reprofile = false;
2449 switch (action) {
2450 case Action_none:
2451 // Keep the old code.
2452 update_trap_state = false;
2453 break;
2454 case Action_maybe_recompile:
2455 // Do not need to invalidate the present code, but we can
2456 // initiate another
2457 // Start compiler without (necessarily) invalidating the nmethod.
2458 // The system will tolerate the old code, but new code should be
2459 // generated when possible.
2460 break;
2461 case Action_reinterpret:
2462 // Go back into the interpreter for a while, and then consider
2463 // recompiling form scratch.
2464 make_not_entrant = true;
2465 // Reset invocation counter for outer most method.
2466 // This will allow the interpreter to exercise the bytecodes
2467 // for a while before recompiling.
2468 // By contrast, Action_make_not_entrant is immediate.
2469 //
2470 // Note that the compiler will track null_check, null_assert,
2471 // range_check, and class_check events and log them as if they
2472 // had been traps taken from compiled code. This will update
2473 // the MDO trap history so that the next compilation will
2474 // properly detect hot trap sites.
2475 reprofile = true;
2476 break;
2477 case Action_make_not_entrant:
2478 // Request immediate recompilation, and get rid of the old code.
2479 // Make them not entrant, so next time they are called they get
2480 // recompiled. Unloaded classes are loaded now so recompile before next
2481 // time they are called. Same for uninitialized. The interpreter will
2482 // link the missing class, if any.
2483 make_not_entrant = true;
2484 break;
2485 case Action_make_not_compilable:
2486 // Give up on compiling this method at all.
2487 make_not_entrant = true;
2488 make_not_compilable = true;
2489 break;
2490 default:
2491 ShouldNotReachHere();
2492 }
2493
2494 #if INCLUDE_JVMCI
2495 // Deoptimization count is used by the CompileBroker to reason about compilations
2496 // it requests so do not pollute the count for deoptimizations in non-default (i.e.
2497 // non-CompilerBroker) compilations.
2498 if (nm->jvmci_skip_profile_deopt()) {
2499 update_trap_state = false;
2500 }
2501 #endif
2502 // Setting +ProfileTraps fixes the following, on all platforms:
2503 // The result is infinite heroic-opt-uncommon-trap/deopt/recompile cycles, since the
2504 // recompile relies on a MethodData* to record heroic opt failures.
2505
2506 // Whether the interpreter is producing MDO data or not, we also need
2507 // to use the MDO to detect hot deoptimization points and control
2508 // aggressive optimization.
2509 bool inc_recompile_count = false;
2510
2511 // Lock to read ProfileData, and ensure lock is not broken by a safepoint
2512 ConditionalMutexLocker ml((trap_mdo != nullptr) ? trap_mdo->extra_data_lock() : nullptr,
2513 (trap_mdo != nullptr),
2514 Mutex::_no_safepoint_check_flag);
2515 ProfileData* pdata = nullptr;
2516 if (ProfileTraps && CompilerConfig::is_c2_or_jvmci_compiler_enabled() && update_trap_state && trap_mdo != nullptr) {
2517 assert(trap_mdo == get_method_data(current, profiled_method, false), "sanity");
2518 uint this_trap_count = 0;
2519 bool maybe_prior_trap = false;
2520 bool maybe_prior_recompile = false;
2521
2522 pdata = query_update_method_data(trap_mdo, trap_bci, reason, true,
2523 #if INCLUDE_JVMCI
2524 nm->is_compiled_by_jvmci() && nm->is_osr_method(),
2525 #endif
2526 nm->method(),
2527 //outputs:
2528 this_trap_count,
2529 maybe_prior_trap,
2530 maybe_prior_recompile);
2531 // Because the interpreter also counts null, div0, range, and class
2532 // checks, these traps from compiled code are double-counted.
2533 // This is harmless; it just means that the PerXTrapLimit values
2534 // are in effect a little smaller than they look.
2535
2536 DeoptReason per_bc_reason = reason_recorded_per_bytecode_if_any(reason);
2537 if (per_bc_reason != Reason_none) {
2538 // Now take action based on the partially known per-BCI history.
2539 if (maybe_prior_trap
2540 && this_trap_count >= (uint)PerBytecodeTrapLimit) {
2541 // If there are too many traps at this BCI, force a recompile.
2542 // This will allow the compiler to see the limit overflow, and
2543 // take corrective action, if possible. The compiler generally
2544 // does not use the exact PerBytecodeTrapLimit value, but instead
2545 // changes its tactics if it sees any traps at all. This provides
2546 // a little hysteresis, delaying a recompile until a trap happens
2547 // several times.
2548 //
2549 // Actually, since there is only one bit of counter per BCI,
2550 // the possible per-BCI counts are {0,1,(per-method count)}.
2551 // This produces accurate results if in fact there is only
2552 // one hot trap site, but begins to get fuzzy if there are
2553 // many sites. For example, if there are ten sites each
2554 // trapping two or more times, they each get the blame for
2555 // all of their traps.
2556 make_not_entrant = true;
2557 }
2558
2559 // Detect repeated recompilation at the same BCI, and enforce a limit.
2560 if (make_not_entrant && maybe_prior_recompile) {
2561 // More than one recompile at this point.
2562 inc_recompile_count = maybe_prior_trap;
2563 }
2564 } else {
2565 // For reasons which are not recorded per-bytecode, we simply
2566 // force recompiles unconditionally.
2567 // (Note that PerMethodRecompilationCutoff is enforced elsewhere.)
2568 make_not_entrant = true;
2569 }
2570
2571 // Go back to the compiler if there are too many traps in this method.
2572 if (this_trap_count >= per_method_trap_limit(reason)) {
2573 // If there are too many traps in this method, force a recompile.
2574 // This will allow the compiler to see the limit overflow, and
2575 // take corrective action, if possible.
2576 // (This condition is an unlikely backstop only, because the
2577 // PerBytecodeTrapLimit is more likely to take effect first,
2578 // if it is applicable.)
2579 make_not_entrant = true;
2580 }
2581
2582 // Here's more hysteresis: If there has been a recompile at
2583 // this trap point already, run the method in the interpreter
2584 // for a while to exercise it more thoroughly.
2585 if (make_not_entrant && maybe_prior_recompile && maybe_prior_trap) {
2586 reprofile = true;
2587 }
2588 }
2589
2590 // Take requested actions on the method:
2591
2592 // Recompile
2593 if (make_not_entrant) {
2594 if (!nm->make_not_entrant(nmethod::InvalidationReason::UNCOMMON_TRAP)) {
2595 return; // the call did not change nmethod's state
2596 }
2597
2598 if (pdata != nullptr) {
2599 // Record the recompilation event, if any.
2600 int tstate0 = pdata->trap_state();
2601 int tstate1 = trap_state_set_recompiled(tstate0, true);
2602 if (tstate1 != tstate0)
2603 pdata->set_trap_state(tstate1);
2604 }
2605
2606 // For code aging we count traps separately here, using make_not_entrant()
2607 // as a guard against simultaneous deopts in multiple threads.
2608 if (reason == Reason_tenured && trap_mdo != nullptr) {
2609 trap_mdo->inc_tenure_traps();
2610 }
2611 }
2612 if (inc_recompile_count) {
2613 trap_mdo->inc_overflow_recompile_count();
2614 if ((uint)trap_mdo->overflow_recompile_count() >
2615 (uint)PerBytecodeRecompilationCutoff) {
2616 // Give up on the method containing the bad BCI.
2617 if (trap_method() == nm->method()) {
2618 make_not_compilable = true;
2619 } else {
2620 trap_method->set_not_compilable("overflow_recompile_count > PerBytecodeRecompilationCutoff", CompLevel_full_optimization);
2621 // But give grace to the enclosing nm->method().
2622 }
2623 }
2624 }
2625
2626 // Reprofile
2627 if (reprofile) {
2628 CompilationPolicy::reprofile(trap_scope, nm->is_osr_method());
2629 }
2630
2631 // Give up compiling
2632 if (make_not_compilable && !nm->method()->is_not_compilable(CompLevel_full_optimization)) {
2633 assert(make_not_entrant, "consistent");
2634 nm->method()->set_not_compilable("give up compiling", CompLevel_full_optimization);
2635 }
2636
2637 if (ProfileExceptionHandlers && trap_mdo != nullptr) {
2638 BitData* exception_handler_data = trap_mdo->exception_handler_bci_to_data_or_null(trap_bci);
2639 if (exception_handler_data != nullptr) {
2640 // uncommon trap at the start of an exception handler.
2641 // C2 generates these for un-entered exception handlers.
2642 // mark the handler as entered to avoid generating
2643 // another uncommon trap the next time the handler is compiled
2644 exception_handler_data->set_exception_handler_entered();
2645 }
2646 }
2647
2648 } // Free marked resources
2649
2650 }
2651 JRT_END
2652
2653 ProfileData*
2654 Deoptimization::query_update_method_data(MethodData* trap_mdo,
2655 int trap_bci,
2656 Deoptimization::DeoptReason reason,
2657 bool update_total_trap_count,
2658 #if INCLUDE_JVMCI
2659 bool is_osr,
2660 #endif
2661 Method* compiled_method,
2662 //outputs:
2663 uint& ret_this_trap_count,
2664 bool& ret_maybe_prior_trap,
2665 bool& ret_maybe_prior_recompile) {
2666 trap_mdo->check_extra_data_locked();
2667
2668 bool maybe_prior_trap = false;
2669 bool maybe_prior_recompile = false;
2670 uint this_trap_count = 0;
2671 if (update_total_trap_count) {
2672 uint idx = reason;
2673 #if INCLUDE_JVMCI
2674 if (is_osr) {
2675 // Upper half of history array used for traps in OSR compilations
2676 idx += Reason_TRAP_HISTORY_LENGTH;
2677 }
2678 #endif
2679 uint prior_trap_count = trap_mdo->trap_count(idx);
2680 this_trap_count = trap_mdo->inc_trap_count(idx);
2681
2682 // If the runtime cannot find a place to store trap history,
2683 // it is estimated based on the general condition of the method.
2684 // If the method has ever been recompiled, or has ever incurred
2685 // a trap with the present reason , then this BCI is assumed
2686 // (pessimistically) to be the culprit.
2687 maybe_prior_trap = (prior_trap_count != 0);
2688 maybe_prior_recompile = (trap_mdo->decompile_count() != 0);
2689 }
2690 ProfileData* pdata = nullptr;
2691
2692
2693 // For reasons which are recorded per bytecode, we check per-BCI data.
2694 DeoptReason per_bc_reason = reason_recorded_per_bytecode_if_any(reason);
2695 assert(per_bc_reason != Reason_none || update_total_trap_count, "must be");
2696 if (per_bc_reason != Reason_none) {
2697 // Find the profile data for this BCI. If there isn't one,
2698 // try to allocate one from the MDO's set of spares.
2699 // This will let us detect a repeated trap at this point.
2700 pdata = trap_mdo->allocate_bci_to_data(trap_bci, reason_is_speculate(reason) ? compiled_method : nullptr);
2701
2702 if (pdata != nullptr) {
2703 if (reason_is_speculate(reason) && !pdata->is_SpeculativeTrapData()) {
2704 if (LogCompilation && xtty != nullptr) {
2705 ttyLocker ttyl;
2706 // no more room for speculative traps in this MDO
2707 xtty->elem("speculative_traps_oom");
2708 }
2709 }
2710 // Query the trap state of this profile datum.
2711 int tstate0 = pdata->trap_state();
2712 if (!trap_state_has_reason(tstate0, per_bc_reason))
2713 maybe_prior_trap = false;
2714 if (!trap_state_is_recompiled(tstate0))
2715 maybe_prior_recompile = false;
2716
2717 // Update the trap state of this profile datum.
2718 int tstate1 = tstate0;
2719 // Record the reason.
2720 tstate1 = trap_state_add_reason(tstate1, per_bc_reason);
2721 // Store the updated state on the MDO, for next time.
2722 if (tstate1 != tstate0)
2723 pdata->set_trap_state(tstate1);
2724 } else {
2725 if (LogCompilation && xtty != nullptr) {
2726 ttyLocker ttyl;
2727 // Missing MDP? Leave a small complaint in the log.
2728 xtty->elem("missing_mdp bci='%d'", trap_bci);
2729 }
2730 }
2731 }
2732
2733 // Return results:
2734 ret_this_trap_count = this_trap_count;
2735 ret_maybe_prior_trap = maybe_prior_trap;
2736 ret_maybe_prior_recompile = maybe_prior_recompile;
2737 return pdata;
2738 }
2739
2740 void
2741 Deoptimization::update_method_data_from_interpreter(MethodData* trap_mdo, int trap_bci, int reason) {
2742 ResourceMark rm;
2743 // Ignored outputs:
2744 uint ignore_this_trap_count;
2745 bool ignore_maybe_prior_trap;
2746 bool ignore_maybe_prior_recompile;
2747 assert(!reason_is_speculate(reason), "reason speculate only used by compiler");
2748 // JVMCI uses the total counts to determine if deoptimizations are happening too frequently -> do not adjust total counts
2749 bool update_total_counts = true JVMCI_ONLY( && !UseJVMCICompiler);
2750
2751 // Lock to read ProfileData, and ensure lock is not broken by a safepoint
2752 MutexLocker ml(trap_mdo->extra_data_lock(), Mutex::_no_safepoint_check_flag);
2753
2754 query_update_method_data(trap_mdo, trap_bci,
2755 (DeoptReason)reason,
2756 update_total_counts,
2757 #if INCLUDE_JVMCI
2758 false,
2759 #endif
2760 nullptr,
2761 ignore_this_trap_count,
2762 ignore_maybe_prior_trap,
2763 ignore_maybe_prior_recompile);
2764 }
2765
2766 Deoptimization::UnrollBlock* Deoptimization::uncommon_trap(JavaThread* current, jint trap_request, jint exec_mode) {
2767 // Enable WXWrite: current function is called from methods compiled by C2 directly
2768 MACOS_AARCH64_ONLY(ThreadWXEnable wx(WXWrite, current));
2769
2770 // Still in Java no safepoints
2771 {
2772 // This enters VM and may safepoint
2773 uncommon_trap_inner(current, trap_request);
2774 }
2775 HandleMark hm(current);
2776 return fetch_unroll_info_helper(current, exec_mode);
2777 }
2778
2779 // Local derived constants.
2780 // Further breakdown of DataLayout::trap_state, as promised by DataLayout.
2781 const int DS_REASON_MASK = ((uint)DataLayout::trap_mask) >> 1;
2782 const int DS_RECOMPILE_BIT = DataLayout::trap_mask - DS_REASON_MASK;
2783
2784 //---------------------------trap_state_reason---------------------------------
2785 Deoptimization::DeoptReason
2786 Deoptimization::trap_state_reason(int trap_state) {
2787 // This assert provides the link between the width of DataLayout::trap_bits
2788 // and the encoding of "recorded" reasons. It ensures there are enough
2789 // bits to store all needed reasons in the per-BCI MDO profile.
2790 assert(DS_REASON_MASK >= Reason_RECORDED_LIMIT, "enough bits");
2791 int recompile_bit = (trap_state & DS_RECOMPILE_BIT);
2792 trap_state -= recompile_bit;
2793 if (trap_state == DS_REASON_MASK) {
2794 return Reason_many;
2795 } else {
2796 assert((int)Reason_none == 0, "state=0 => Reason_none");
2797 return (DeoptReason)trap_state;
2798 }
2799 }
2800 //-------------------------trap_state_has_reason-------------------------------
2801 int Deoptimization::trap_state_has_reason(int trap_state, int reason) {
2802 assert(reason_is_recorded_per_bytecode((DeoptReason)reason), "valid reason");
2803 assert(DS_REASON_MASK >= Reason_RECORDED_LIMIT, "enough bits");
2804 int recompile_bit = (trap_state & DS_RECOMPILE_BIT);
2805 trap_state -= recompile_bit;
2806 if (trap_state == DS_REASON_MASK) {
2807 return -1; // true, unspecifically (bottom of state lattice)
2808 } else if (trap_state == reason) {
2809 return 1; // true, definitely
2810 } else if (trap_state == 0) {
2811 return 0; // false, definitely (top of state lattice)
2812 } else {
2813 return 0; // false, definitely
2814 }
2815 }
2816 //-------------------------trap_state_add_reason-------------------------------
2817 int Deoptimization::trap_state_add_reason(int trap_state, int reason) {
2818 assert(reason_is_recorded_per_bytecode((DeoptReason)reason) || reason == Reason_many, "valid reason");
2819 int recompile_bit = (trap_state & DS_RECOMPILE_BIT);
2820 trap_state -= recompile_bit;
2821 if (trap_state == DS_REASON_MASK) {
2822 return trap_state + recompile_bit; // already at state lattice bottom
2823 } else if (trap_state == reason) {
2824 return trap_state + recompile_bit; // the condition is already true
2825 } else if (trap_state == 0) {
2826 return reason + recompile_bit; // no condition has yet been true
2827 } else {
2828 return DS_REASON_MASK + recompile_bit; // fall to state lattice bottom
2829 }
2830 }
2831 //-----------------------trap_state_is_recompiled------------------------------
2832 bool Deoptimization::trap_state_is_recompiled(int trap_state) {
2833 return (trap_state & DS_RECOMPILE_BIT) != 0;
2834 }
2835 //-----------------------trap_state_set_recompiled-----------------------------
2836 int Deoptimization::trap_state_set_recompiled(int trap_state, bool z) {
2837 if (z) return trap_state | DS_RECOMPILE_BIT;
2838 else return trap_state & ~DS_RECOMPILE_BIT;
2839 }
2840 //---------------------------format_trap_state---------------------------------
2841 // This is used for debugging and diagnostics, including LogFile output.
2842 const char* Deoptimization::format_trap_state(char* buf, size_t buflen,
2843 int trap_state) {
2844 assert(buflen > 0, "sanity");
2845 DeoptReason reason = trap_state_reason(trap_state);
2846 bool recomp_flag = trap_state_is_recompiled(trap_state);
2847 // Re-encode the state from its decoded components.
2848 int decoded_state = 0;
2849 if (reason_is_recorded_per_bytecode(reason) || reason == Reason_many)
2850 decoded_state = trap_state_add_reason(decoded_state, reason);
2851 if (recomp_flag)
2852 decoded_state = trap_state_set_recompiled(decoded_state, recomp_flag);
2853 // If the state re-encodes properly, format it symbolically.
2854 // Because this routine is used for debugging and diagnostics,
2855 // be robust even if the state is a strange value.
2856 size_t len;
2857 if (decoded_state != trap_state) {
2858 // Random buggy state that doesn't decode??
2859 len = jio_snprintf(buf, buflen, "#%d", trap_state);
2860 } else {
2861 len = jio_snprintf(buf, buflen, "%s%s",
2862 trap_reason_name(reason),
2863 recomp_flag ? " recompiled" : "");
2864 }
2865 return buf;
2866 }
2867
2868
2869 //--------------------------------statics--------------------------------------
2870 const char* Deoptimization::_trap_reason_name[] = {
2871 // Note: Keep this in sync. with enum DeoptReason.
2872 "none",
2873 "null_check",
2874 "null_assert" JVMCI_ONLY("_or_unreached0"),
2875 "range_check",
2876 "class_check",
2877 "array_check",
2878 "intrinsic" JVMCI_ONLY("_or_type_checked_inlining"),
2879 "bimorphic" JVMCI_ONLY("_or_optimized_type_check"),
2880 "profile_predicate",
2881 "auto_vectorization_check",
2882 "unloaded",
2883 "uninitialized",
2884 "initialized",
2885 "unreached",
2886 "unhandled",
2887 "constraint",
2888 "div0_check",
2889 "age",
2890 "predicate",
2891 "loop_limit_check",
2892 "speculate_class_check",
2893 "speculate_null_check",
2894 "speculate_null_assert",
2895 "unstable_if",
2896 "unstable_fused_if",
2897 "receiver_constraint",
2898 "not_compiled_exception_handler",
2899 "short_running_loop" JVMCI_ONLY("_or_aliasing"),
2900 #if INCLUDE_JVMCI
2901 "transfer_to_interpreter",
2902 "unresolved",
2903 "jsr_mismatch",
2904 #endif
2905 "tenured"
2906 };
2907 const char* Deoptimization::_trap_action_name[] = {
2908 // Note: Keep this in sync. with enum DeoptAction.
2909 "none",
2910 "maybe_recompile",
2911 "reinterpret",
2912 "make_not_entrant",
2913 "make_not_compilable"
2914 };
2915
2916 const char* Deoptimization::trap_reason_name(int reason) {
2917 // Check that every reason has a name
2918 STATIC_ASSERT(sizeof(_trap_reason_name)/sizeof(const char*) == Reason_LIMIT);
2919
2920 if (reason == Reason_many) return "many";
2921 if ((uint)reason < Reason_LIMIT)
2922 return _trap_reason_name[reason];
2923 static char buf[20];
2924 os::snprintf_checked(buf, sizeof(buf), "reason%d", reason);
2925 return buf;
2926 }
2927 const char* Deoptimization::trap_action_name(int action) {
2928 // Check that every action has a name
2929 STATIC_ASSERT(sizeof(_trap_action_name)/sizeof(const char*) == Action_LIMIT);
2930
2931 if ((uint)action < Action_LIMIT)
2932 return _trap_action_name[action];
2933 static char buf[20];
2934 os::snprintf_checked(buf, sizeof(buf), "action%d", action);
2935 return buf;
2936 }
2937
2938 // This is used for debugging and diagnostics, including LogFile output.
2939 const char* Deoptimization::format_trap_request(char* buf, size_t buflen,
2940 int trap_request) {
2941 jint unloaded_class_index = trap_request_index(trap_request);
2942 const char* reason = trap_reason_name(trap_request_reason(trap_request));
2943 const char* action = trap_action_name(trap_request_action(trap_request));
2944 #if INCLUDE_JVMCI
2945 int debug_id = trap_request_debug_id(trap_request);
2946 #endif
2947 size_t len;
2948 if (unloaded_class_index < 0) {
2949 len = jio_snprintf(buf, buflen, "reason='%s' action='%s'" JVMCI_ONLY(" debug_id='%d'"),
2950 reason, action
2951 #if INCLUDE_JVMCI
2952 ,debug_id
2953 #endif
2954 );
2955 } else {
2956 len = jio_snprintf(buf, buflen, "reason='%s' action='%s' index='%d'" JVMCI_ONLY(" debug_id='%d'"),
2957 reason, action, unloaded_class_index
2958 #if INCLUDE_JVMCI
2959 ,debug_id
2960 #endif
2961 );
2962 }
2963 return buf;
2964 }
2965
2966 juint Deoptimization::_deoptimization_hist
2967 [Deoptimization::Reason_LIMIT]
2968 [1 + Deoptimization::Action_LIMIT]
2969 [Deoptimization::BC_CASE_LIMIT]
2970 = {0};
2971
2972 enum {
2973 LSB_BITS = 8,
2974 LSB_MASK = right_n_bits(LSB_BITS)
2975 };
2976
2977 void Deoptimization::gather_statistics(DeoptReason reason, DeoptAction action,
2978 Bytecodes::Code bc) {
2979 assert(reason >= 0 && reason < Reason_LIMIT, "oob");
2980 assert(action >= 0 && action < Action_LIMIT, "oob");
2981 _deoptimization_hist[Reason_none][0][0] += 1; // total
2982 _deoptimization_hist[reason][0][0] += 1; // per-reason total
2983 juint* cases = _deoptimization_hist[reason][1+action];
2984 juint* bc_counter_addr = nullptr;
2985 juint bc_counter = 0;
2986 // Look for an unused counter, or an exact match to this BC.
2987 if (bc != Bytecodes::_illegal) {
2988 for (int bc_case = 0; bc_case < BC_CASE_LIMIT; bc_case++) {
2989 juint* counter_addr = &cases[bc_case];
2990 juint counter = *counter_addr;
2991 if ((counter == 0 && bc_counter_addr == nullptr)
2992 || (Bytecodes::Code)(counter & LSB_MASK) == bc) {
2993 // this counter is either free or is already devoted to this BC
2994 bc_counter_addr = counter_addr;
2995 bc_counter = counter | bc;
2996 }
2997 }
2998 }
2999 if (bc_counter_addr == nullptr) {
3000 // Overflow, or no given bytecode.
3001 bc_counter_addr = &cases[BC_CASE_LIMIT-1];
3002 bc_counter = (*bc_counter_addr & ~LSB_MASK); // clear LSB
3003 }
3004 *bc_counter_addr = bc_counter + (1 << LSB_BITS);
3005 }
3006
3007 jint Deoptimization::total_deoptimization_count() {
3008 return _deoptimization_hist[Reason_none][0][0];
3009 }
3010
3011 // Get the deopt count for a specific reason and a specific action. If either
3012 // one of 'reason' or 'action' is null, the method returns the sum of all
3013 // deoptimizations with the specific 'action' or 'reason' respectively.
3014 // If both arguments are null, the method returns the total deopt count.
3015 jint Deoptimization::deoptimization_count(const char *reason_str, const char *action_str) {
3016 if (reason_str == nullptr && action_str == nullptr) {
3017 return total_deoptimization_count();
3018 }
3019 juint counter = 0;
3020 for (int reason = 0; reason < Reason_LIMIT; reason++) {
3021 if (reason_str == nullptr || !strcmp(reason_str, trap_reason_name(reason))) {
3022 for (int action = 0; action < Action_LIMIT; action++) {
3023 if (action_str == nullptr || !strcmp(action_str, trap_action_name(action))) {
3024 juint* cases = _deoptimization_hist[reason][1+action];
3025 for (int bc_case = 0; bc_case < BC_CASE_LIMIT; bc_case++) {
3026 counter += cases[bc_case] >> LSB_BITS;
3027 }
3028 }
3029 }
3030 }
3031 }
3032 return counter;
3033 }
3034
3035 void Deoptimization::print_statistics() {
3036 juint total = total_deoptimization_count();
3037 juint account = total;
3038 if (total != 0) {
3039 ttyLocker ttyl;
3040 if (xtty != nullptr) xtty->head("statistics type='deoptimization'");
3041 tty->print_cr("Deoptimization traps recorded:");
3042 #define PRINT_STAT_LINE(name, r) \
3043 tty->print_cr(" %4d (%4.1f%%) %s", (int)(r), ((r) * 100.0) / total, name);
3044 PRINT_STAT_LINE("total", total);
3045 // For each non-zero entry in the histogram, print the reason,
3046 // the action, and (if specifically known) the type of bytecode.
3047 for (int reason = 0; reason < Reason_LIMIT; reason++) {
3048 for (int action = 0; action < Action_LIMIT; action++) {
3049 juint* cases = _deoptimization_hist[reason][1+action];
3050 for (int bc_case = 0; bc_case < BC_CASE_LIMIT; bc_case++) {
3051 juint counter = cases[bc_case];
3052 if (counter != 0) {
3053 char name[1*K];
3054 Bytecodes::Code bc = (Bytecodes::Code)(counter & LSB_MASK);
3055 os::snprintf_checked(name, sizeof(name), "%s/%s/%s",
3056 trap_reason_name(reason),
3057 trap_action_name(action),
3058 Bytecodes::is_defined(bc)? Bytecodes::name(bc): "other");
3059 juint r = counter >> LSB_BITS;
3060 tty->print_cr(" %40s: " UINT32_FORMAT " (%.1f%%)", name, r, (r * 100.0) / total);
3061 account -= r;
3062 }
3063 }
3064 }
3065 }
3066 if (account != 0) {
3067 PRINT_STAT_LINE("unaccounted", account);
3068 }
3069 #undef PRINT_STAT_LINE
3070 if (xtty != nullptr) xtty->tail("statistics");
3071 }
3072 }
3073
3074 #else // COMPILER2_OR_JVMCI
3075
3076
3077 // Stubs for C1 only system.
3078 bool Deoptimization::trap_state_is_recompiled(int trap_state) {
3079 return false;
3080 }
3081
3082 const char* Deoptimization::trap_reason_name(int reason) {
3083 return "unknown";
3084 }
3085
3086 jint Deoptimization::total_deoptimization_count() {
3087 return 0;
3088 }
3089
3090 jint Deoptimization::deoptimization_count(const char *reason_str, const char *action_str) {
3091 return 0;
3092 }
3093
3094 void Deoptimization::print_statistics() {
3095 // no output
3096 }
3097
3098 void
3099 Deoptimization::update_method_data_from_interpreter(MethodData* trap_mdo, int trap_bci, int reason) {
3100 // no update
3101 }
3102
3103 int Deoptimization::trap_state_has_reason(int trap_state, int reason) {
3104 return 0;
3105 }
3106
3107 void Deoptimization::gather_statistics(DeoptReason reason, DeoptAction action,
3108 Bytecodes::Code bc) {
3109 // no update
3110 }
3111
3112 const char* Deoptimization::format_trap_state(char* buf, size_t buflen,
3113 int trap_state) {
3114 jio_snprintf(buf, buflen, "#%d", trap_state);
3115 return buf;
3116 }
3117
3118 #endif // COMPILER2_OR_JVMCI