1 /*
2 * Copyright (c) 1997, 2025, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation.
8 *
9 * This code is distributed in the hope that it will be useful, but WITHOUT
10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
12 * version 2 for more details (a copy is included in the LICENSE file that
13 * accompanied this code).
14 *
15 * You should have received a copy of the GNU General Public License version
16 * 2 along with this work; if not, write to the Free Software Foundation,
17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
18 *
19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
20 * or visit www.oracle.com if you need additional information or have any
21 * questions.
22 *
23 */
24
25 #include "classfile/javaClasses.inline.hpp"
26 #include "classfile/symbolTable.hpp"
27 #include "classfile/systemDictionary.hpp"
28 #include "classfile/vmClasses.hpp"
29 #include "code/codeCache.hpp"
30 #include "code/debugInfoRec.hpp"
31 #include "code/nmethod.hpp"
32 #include "code/pcDesc.hpp"
33 #include "code/scopeDesc.hpp"
34 #include "compiler/compilationPolicy.hpp"
35 #include "compiler/compilerDefinitions.inline.hpp"
36 #include "gc/shared/collectedHeap.hpp"
37 #include "gc/shared/memAllocator.hpp"
38 #include "interpreter/bytecode.hpp"
39 #include "interpreter/bytecode.inline.hpp"
40 #include "interpreter/bytecodeStream.hpp"
41 #include "interpreter/interpreter.hpp"
42 #include "interpreter/oopMapCache.hpp"
43 #include "jvm.h"
44 #include "logging/log.hpp"
45 #include "logging/logLevel.hpp"
46 #include "logging/logMessage.hpp"
47 #include "logging/logStream.hpp"
48 #include "memory/allocation.inline.hpp"
49 #include "memory/oopFactory.hpp"
50 #include "memory/resourceArea.hpp"
51 #include "memory/universe.hpp"
52 #include "oops/constantPool.hpp"
53 #include "oops/fieldStreams.inline.hpp"
54 #include "oops/method.hpp"
55 #include "oops/objArrayKlass.hpp"
56 #include "oops/objArrayOop.inline.hpp"
57 #include "oops/oop.inline.hpp"
58 #include "oops/typeArrayOop.inline.hpp"
59 #include "oops/verifyOopClosure.hpp"
60 #include "prims/jvmtiDeferredUpdates.hpp"
61 #include "prims/jvmtiExport.hpp"
62 #include "prims/jvmtiThreadState.hpp"
63 #include "prims/methodHandles.hpp"
64 #include "prims/vectorSupport.hpp"
65 #include "runtime/atomic.hpp"
66 #include "runtime/basicLock.inline.hpp"
67 #include "runtime/continuation.hpp"
68 #include "runtime/continuationEntry.inline.hpp"
69 #include "runtime/deoptimization.hpp"
70 #include "runtime/escapeBarrier.hpp"
71 #include "runtime/fieldDescriptor.hpp"
72 #include "runtime/fieldDescriptor.inline.hpp"
73 #include "runtime/frame.inline.hpp"
74 #include "runtime/handles.inline.hpp"
75 #include "runtime/interfaceSupport.inline.hpp"
76 #include "runtime/javaThread.hpp"
77 #include "runtime/jniHandles.inline.hpp"
78 #include "runtime/keepStackGCProcessed.hpp"
79 #include "runtime/lightweightSynchronizer.hpp"
80 #include "runtime/lockStack.inline.hpp"
81 #include "runtime/objectMonitor.inline.hpp"
82 #include "runtime/osThread.hpp"
83 #include "runtime/safepointVerifiers.hpp"
84 #include "runtime/sharedRuntime.hpp"
85 #include "runtime/signature.hpp"
86 #include "runtime/stackFrameStream.inline.hpp"
87 #include "runtime/stackValue.hpp"
88 #include "runtime/stackWatermarkSet.hpp"
89 #include "runtime/stubRoutines.hpp"
90 #include "runtime/synchronizer.inline.hpp"
91 #include "runtime/threadSMR.hpp"
92 #include "runtime/threadWXSetters.inline.hpp"
93 #include "runtime/vframe.hpp"
94 #include "runtime/vframeArray.hpp"
95 #include "runtime/vframe_hp.hpp"
96 #include "runtime/vmOperations.hpp"
97 #include "utilities/checkedCast.hpp"
98 #include "utilities/events.hpp"
99 #include "utilities/growableArray.hpp"
100 #include "utilities/macros.hpp"
101 #include "utilities/preserveException.hpp"
102 #include "utilities/xmlstream.hpp"
103 #if INCLUDE_JFR
104 #include "jfr/jfr.inline.hpp"
105 #include "jfr/jfrEvents.hpp"
106 #include "jfr/metadata/jfrSerializer.hpp"
107 #endif
108
109 uint64_t DeoptimizationScope::_committed_deopt_gen = 0;
110 uint64_t DeoptimizationScope::_active_deopt_gen = 1;
111 bool DeoptimizationScope::_committing_in_progress = false;
112
113 DeoptimizationScope::DeoptimizationScope() : _required_gen(0) {
114 DEBUG_ONLY(_deopted = false;)
115
116 MutexLocker ml(NMethodState_lock, Mutex::_no_safepoint_check_flag);
117 // If there is nothing to deopt _required_gen is the same as comitted.
118 _required_gen = DeoptimizationScope::_committed_deopt_gen;
119 }
120
121 DeoptimizationScope::~DeoptimizationScope() {
122 assert(_deopted, "Deopt not executed");
123 }
124
125 void DeoptimizationScope::mark(nmethod* nm, bool inc_recompile_counts) {
126 if (!nm->can_be_deoptimized()) {
127 return;
128 }
129
130 ConditionalMutexLocker ml(NMethodState_lock, !NMethodState_lock->owned_by_self(), Mutex::_no_safepoint_check_flag);
131
132 // If it's already marked but we still need it to be deopted.
133 if (nm->is_marked_for_deoptimization()) {
134 dependent(nm);
135 return;
136 }
137
138 nmethod::DeoptimizationStatus status =
139 inc_recompile_counts ? nmethod::deoptimize : nmethod::deoptimize_noupdate;
140 Atomic::store(&nm->_deoptimization_status, status);
141
142 // Make sure active is not committed
143 assert(DeoptimizationScope::_committed_deopt_gen < DeoptimizationScope::_active_deopt_gen, "Must be");
144 assert(nm->_deoptimization_generation == 0, "Is already marked");
145
146 nm->_deoptimization_generation = DeoptimizationScope::_active_deopt_gen;
147 _required_gen = DeoptimizationScope::_active_deopt_gen;
148 }
149
150 void DeoptimizationScope::dependent(nmethod* nm) {
151 ConditionalMutexLocker ml(NMethodState_lock, !NMethodState_lock->owned_by_self(), Mutex::_no_safepoint_check_flag);
152
153 // A method marked by someone else may have a _required_gen lower than what we marked with.
154 // Therefore only store it if it's higher than _required_gen.
155 if (_required_gen < nm->_deoptimization_generation) {
156 _required_gen = nm->_deoptimization_generation;
157 }
158 }
159
160 void DeoptimizationScope::deoptimize_marked() {
161 assert(!_deopted, "Already deopted");
162
163 // We are not alive yet.
164 if (!Universe::is_fully_initialized()) {
165 DEBUG_ONLY(_deopted = true;)
166 return;
167 }
168
169 // Safepoints are a special case, handled here.
170 if (SafepointSynchronize::is_at_safepoint()) {
171 DeoptimizationScope::_committed_deopt_gen = DeoptimizationScope::_active_deopt_gen;
172 DeoptimizationScope::_active_deopt_gen++;
173 Deoptimization::deoptimize_all_marked();
174 DEBUG_ONLY(_deopted = true;)
175 return;
176 }
177
178 uint64_t comitting = 0;
179 bool wait = false;
180 while (true) {
181 {
182 ConditionalMutexLocker ml(NMethodState_lock, !NMethodState_lock->owned_by_self(), Mutex::_no_safepoint_check_flag);
183
184 // First we check if we or someone else already deopted the gen we want.
185 if (DeoptimizationScope::_committed_deopt_gen >= _required_gen) {
186 DEBUG_ONLY(_deopted = true;)
187 return;
188 }
189 if (!_committing_in_progress) {
190 // The version we are about to commit.
191 comitting = DeoptimizationScope::_active_deopt_gen;
192 // Make sure new marks use a higher gen.
193 DeoptimizationScope::_active_deopt_gen++;
194 _committing_in_progress = true;
195 wait = false;
196 } else {
197 // Another thread is handshaking and committing a gen.
198 wait = true;
199 }
200 }
201 if (wait) {
202 // Wait and let the concurrent handshake be performed.
203 ThreadBlockInVM tbivm(JavaThread::current());
204 os::naked_yield();
205 } else {
206 // Performs the handshake.
207 Deoptimization::deoptimize_all_marked(); // May safepoint and an additional deopt may have occurred.
208 DEBUG_ONLY(_deopted = true;)
209 {
210 ConditionalMutexLocker ml(NMethodState_lock, !NMethodState_lock->owned_by_self(), Mutex::_no_safepoint_check_flag);
211
212 // Make sure that committed doesn't go backwards.
213 // Should only happen if we did a deopt during a safepoint above.
214 if (DeoptimizationScope::_committed_deopt_gen < comitting) {
215 DeoptimizationScope::_committed_deopt_gen = comitting;
216 }
217 _committing_in_progress = false;
218
219 assert(DeoptimizationScope::_committed_deopt_gen >= _required_gen, "Must be");
220
221 return;
222 }
223 }
224 }
225 }
226
227 Deoptimization::UnrollBlock::UnrollBlock(int size_of_deoptimized_frame,
228 int caller_adjustment,
229 int caller_actual_parameters,
230 int number_of_frames,
231 intptr_t* frame_sizes,
232 address* frame_pcs,
233 BasicType return_type,
234 int exec_mode) {
235 _size_of_deoptimized_frame = size_of_deoptimized_frame;
236 _caller_adjustment = caller_adjustment;
237 _caller_actual_parameters = caller_actual_parameters;
238 _number_of_frames = number_of_frames;
239 _frame_sizes = frame_sizes;
240 _frame_pcs = frame_pcs;
241 _register_block = NEW_C_HEAP_ARRAY(intptr_t, RegisterMap::reg_count * 2, mtCompiler);
242 _return_type = return_type;
243 _initial_info = 0;
244 // PD (x86 only)
245 _counter_temp = 0;
246 _unpack_kind = exec_mode;
247 _sender_sp_temp = 0;
248
249 _total_frame_sizes = size_of_frames();
250 assert(exec_mode >= 0 && exec_mode < Unpack_LIMIT, "Unexpected exec_mode");
251 }
252
253 Deoptimization::UnrollBlock::~UnrollBlock() {
254 FREE_C_HEAP_ARRAY(intptr_t, _frame_sizes);
255 FREE_C_HEAP_ARRAY(intptr_t, _frame_pcs);
256 FREE_C_HEAP_ARRAY(intptr_t, _register_block);
257 }
258
259 int Deoptimization::UnrollBlock::size_of_frames() const {
260 // Account first for the adjustment of the initial frame
261 intptr_t result = _caller_adjustment;
262 for (int index = 0; index < number_of_frames(); index++) {
263 result += frame_sizes()[index];
264 }
265 return checked_cast<int>(result);
266 }
267
268 void Deoptimization::UnrollBlock::print() {
269 ResourceMark rm;
270 stringStream st;
271 st.print_cr("UnrollBlock");
272 st.print_cr(" size_of_deoptimized_frame = %d", _size_of_deoptimized_frame);
273 st.print( " frame_sizes: ");
274 for (int index = 0; index < number_of_frames(); index++) {
275 st.print("%zd ", frame_sizes()[index]);
276 }
277 st.cr();
278 tty->print_raw(st.freeze());
279 }
280
281 // In order to make fetch_unroll_info work properly with escape
282 // analysis, the method was changed from JRT_LEAF to JRT_BLOCK_ENTRY.
283 // The actual reallocation of previously eliminated objects occurs in realloc_objects,
284 // which is called from the method fetch_unroll_info_helper below.
285 JRT_BLOCK_ENTRY(Deoptimization::UnrollBlock*, Deoptimization::fetch_unroll_info(JavaThread* current, int exec_mode))
286 // fetch_unroll_info() is called at the beginning of the deoptimization
287 // handler. Note this fact before we start generating temporary frames
288 // that can confuse an asynchronous stack walker. This counter is
289 // decremented at the end of unpack_frames().
290 current->inc_in_deopt_handler();
291
292 if (exec_mode == Unpack_exception) {
293 // When we get here, a callee has thrown an exception into a deoptimized
294 // frame. That throw might have deferred stack watermark checking until
295 // after unwinding. So we deal with such deferred requests here.
296 StackWatermarkSet::after_unwind(current);
297 }
298
299 return fetch_unroll_info_helper(current, exec_mode);
300 JRT_END
301
302 #if COMPILER2_OR_JVMCI
303 // print information about reallocated objects
304 static void print_objects(JavaThread* deoptee_thread,
305 GrowableArray<ScopeValue*>* objects, bool realloc_failures) {
306 ResourceMark rm;
307 stringStream st; // change to logStream with logging
308 st.print_cr("REALLOC OBJECTS in thread " INTPTR_FORMAT, p2i(deoptee_thread));
309 fieldDescriptor fd;
310
311 for (int i = 0; i < objects->length(); i++) {
312 ObjectValue* sv = (ObjectValue*) objects->at(i);
313 Handle obj = sv->value();
314
315 if (obj.is_null()) {
316 st.print_cr(" nullptr");
317 continue;
318 }
319
320 Klass* k = java_lang_Class::as_Klass(sv->klass()->as_ConstantOopReadValue()->value()());
321
322 st.print(" object <" INTPTR_FORMAT "> of type ", p2i(sv->value()()));
323 k->print_value_on(&st);
324 st.print_cr(" allocated (%zu bytes)", obj->size() * HeapWordSize);
325
326 if (Verbose && k != nullptr) {
327 k->oop_print_on(obj(), &st);
328 }
329 }
330 tty->print_raw(st.freeze());
331 }
332
333 static bool rematerialize_objects(JavaThread* thread, int exec_mode, nmethod* compiled_method,
334 frame& deoptee, RegisterMap& map, GrowableArray<compiledVFrame*>* chunk,
335 bool& deoptimized_objects) {
336 bool realloc_failures = false;
337 assert (chunk->at(0)->scope() != nullptr,"expect only compiled java frames");
338
339 JavaThread* deoptee_thread = chunk->at(0)->thread();
340 assert(exec_mode == Deoptimization::Unpack_none || (deoptee_thread == thread),
341 "a frame can only be deoptimized by the owner thread");
342
343 GrowableArray<ScopeValue*>* objects = chunk->at(0)->scope()->objects_to_rematerialize(deoptee, map);
344
345 // The flag return_oop() indicates call sites which return oop
346 // in compiled code. Such sites include java method calls,
347 // runtime calls (for example, used to allocate new objects/arrays
348 // on slow code path) and any other calls generated in compiled code.
349 // It is not guaranteed that we can get such information here only
350 // by analyzing bytecode in deoptimized frames. This is why this flag
351 // is set during method compilation (see Compile::Process_OopMap_Node()).
352 // If the previous frame was popped or if we are dispatching an exception,
353 // we don't have an oop result.
354 bool save_oop_result = chunk->at(0)->scope()->return_oop() && !thread->popframe_forcing_deopt_reexecution() && (exec_mode == Deoptimization::Unpack_deopt);
355 Handle return_value;
356 if (save_oop_result) {
357 // Reallocation may trigger GC. If deoptimization happened on return from
358 // call which returns oop we need to save it since it is not in oopmap.
359 oop result = deoptee.saved_oop_result(&map);
360 assert(oopDesc::is_oop_or_null(result), "must be oop");
361 return_value = Handle(thread, result);
362 assert(Universe::heap()->is_in_or_null(result), "must be heap pointer");
363 if (TraceDeoptimization) {
364 tty->print_cr("SAVED OOP RESULT " INTPTR_FORMAT " in thread " INTPTR_FORMAT, p2i(result), p2i(thread));
365 tty->cr();
366 }
367 }
368 if (objects != nullptr) {
369 if (exec_mode == Deoptimization::Unpack_none) {
370 assert(thread->thread_state() == _thread_in_vm, "assumption");
371 JavaThread* THREAD = thread; // For exception macros.
372 // Clear pending OOM if reallocation fails and return true indicating allocation failure
373 realloc_failures = Deoptimization::realloc_objects(thread, &deoptee, &map, objects, CHECK_AND_CLEAR_(true));
374 deoptimized_objects = true;
375 } else {
376 JavaThread* current = thread; // For JRT_BLOCK
377 JRT_BLOCK
378 realloc_failures = Deoptimization::realloc_objects(thread, &deoptee, &map, objects, THREAD);
379 JRT_END
380 }
381 guarantee(compiled_method != nullptr, "deopt must be associated with an nmethod");
382 bool is_jvmci = compiled_method->is_compiled_by_jvmci();
383 Deoptimization::reassign_fields(&deoptee, &map, objects, realloc_failures, is_jvmci);
384 if (TraceDeoptimization) {
385 print_objects(deoptee_thread, objects, realloc_failures);
386 }
387 }
388 if (save_oop_result) {
389 // Restore result.
390 deoptee.set_saved_oop_result(&map, return_value());
391 }
392 return realloc_failures;
393 }
394
395 static void restore_eliminated_locks(JavaThread* thread, GrowableArray<compiledVFrame*>* chunk, bool realloc_failures,
396 frame& deoptee, int exec_mode, bool& deoptimized_objects) {
397 JavaThread* deoptee_thread = chunk->at(0)->thread();
398 assert(!EscapeBarrier::objs_are_deoptimized(deoptee_thread, deoptee.id()), "must relock just once");
399 assert(thread == Thread::current(), "should be");
400 HandleMark hm(thread);
401 #ifndef PRODUCT
402 bool first = true;
403 #endif // !PRODUCT
404 // Start locking from outermost/oldest frame
405 for (int i = (chunk->length() - 1); i >= 0; i--) {
406 compiledVFrame* cvf = chunk->at(i);
407 assert (cvf->scope() != nullptr,"expect only compiled java frames");
408 GrowableArray<MonitorInfo*>* monitors = cvf->monitors();
409 if (monitors->is_nonempty()) {
410 bool relocked = Deoptimization::relock_objects(thread, monitors, deoptee_thread, deoptee,
411 exec_mode, realloc_failures);
412 deoptimized_objects = deoptimized_objects || relocked;
413 #ifndef PRODUCT
414 if (PrintDeoptimizationDetails) {
415 ResourceMark rm;
416 stringStream st;
417 for (int j = 0; j < monitors->length(); j++) {
418 MonitorInfo* mi = monitors->at(j);
419 if (mi->eliminated()) {
420 if (first) {
421 first = false;
422 st.print_cr("RELOCK OBJECTS in thread " INTPTR_FORMAT, p2i(thread));
423 }
424 if (exec_mode == Deoptimization::Unpack_none) {
425 ObjectMonitor* monitor = deoptee_thread->current_waiting_monitor();
426 if (monitor != nullptr && monitor->object() == mi->owner()) {
427 st.print_cr(" object <" INTPTR_FORMAT "> DEFERRED relocking after wait", p2i(mi->owner()));
428 continue;
429 }
430 }
431 if (mi->owner_is_scalar_replaced()) {
432 Klass* k = java_lang_Class::as_Klass(mi->owner_klass());
433 st.print_cr(" failed reallocation for klass %s", k->external_name());
434 } else {
435 st.print_cr(" object <" INTPTR_FORMAT "> locked", p2i(mi->owner()));
436 }
437 }
438 }
439 tty->print_raw(st.freeze());
440 }
441 #endif // !PRODUCT
442 }
443 }
444 }
445
446 // Deoptimize objects, that is reallocate and relock them, just before they escape through JVMTI.
447 // The given vframes cover one physical frame.
448 bool Deoptimization::deoptimize_objects_internal(JavaThread* thread, GrowableArray<compiledVFrame*>* chunk,
449 bool& realloc_failures) {
450 frame deoptee = chunk->at(0)->fr();
451 JavaThread* deoptee_thread = chunk->at(0)->thread();
452 nmethod* nm = deoptee.cb()->as_nmethod_or_null();
453 RegisterMap map(chunk->at(0)->register_map());
454 bool deoptimized_objects = false;
455
456 bool const jvmci_enabled = JVMCI_ONLY(EnableJVMCI) NOT_JVMCI(false);
457
458 // Reallocate the non-escaping objects and restore their fields.
459 if (jvmci_enabled COMPILER2_PRESENT(|| (DoEscapeAnalysis && EliminateAllocations)
460 || EliminateAutoBox || EnableVectorAggressiveReboxing)) {
461 realloc_failures = rematerialize_objects(thread, Unpack_none, nm, deoptee, map, chunk, deoptimized_objects);
462 }
463
464 // MonitorInfo structures used in eliminate_locks are not GC safe.
465 NoSafepointVerifier no_safepoint;
466
467 // Now relock objects if synchronization on them was eliminated.
468 if (jvmci_enabled COMPILER2_PRESENT(|| ((DoEscapeAnalysis || EliminateNestedLocks) && EliminateLocks))) {
469 restore_eliminated_locks(thread, chunk, realloc_failures, deoptee, Unpack_none, deoptimized_objects);
470 }
471 return deoptimized_objects;
472 }
473 #endif // COMPILER2_OR_JVMCI
474
475 // This is factored, since it is both called from a JRT_LEAF (deoptimization) and a JRT_ENTRY (uncommon_trap)
476 Deoptimization::UnrollBlock* Deoptimization::fetch_unroll_info_helper(JavaThread* current, int exec_mode) {
477 JFR_ONLY(Jfr::check_and_process_sample_request(current);)
478 // When we get here we are about to unwind the deoptee frame. In order to
479 // catch not yet safe to use frames, the following stack watermark barrier
480 // poll will make such frames safe to use.
481 StackWatermarkSet::before_unwind(current);
482
483 // Note: there is a safepoint safety issue here. No matter whether we enter
484 // via vanilla deopt or uncommon trap we MUST NOT stop at a safepoint once
485 // the vframeArray is created.
486 //
487
488 // Allocate our special deoptimization ResourceMark
489 DeoptResourceMark* dmark = new DeoptResourceMark(current);
490 assert(current->deopt_mark() == nullptr, "Pending deopt!");
491 current->set_deopt_mark(dmark);
492
493 frame stub_frame = current->last_frame(); // Makes stack walkable as side effect
494 RegisterMap map(current,
495 RegisterMap::UpdateMap::include,
496 RegisterMap::ProcessFrames::include,
497 RegisterMap::WalkContinuation::skip);
498 RegisterMap dummy_map(current,
499 RegisterMap::UpdateMap::skip,
500 RegisterMap::ProcessFrames::include,
501 RegisterMap::WalkContinuation::skip);
502 // Now get the deoptee with a valid map
503 frame deoptee = stub_frame.sender(&map);
504 // Set the deoptee nmethod
505 assert(current->deopt_compiled_method() == nullptr, "Pending deopt!");
506 nmethod* nm = deoptee.cb()->as_nmethod_or_null();
507 current->set_deopt_compiled_method(nm);
508
509 if (VerifyStack) {
510 current->validate_frame_layout();
511 }
512
513 // Create a growable array of VFrames where each VFrame represents an inlined
514 // Java frame. This storage is allocated with the usual system arena.
515 assert(deoptee.is_compiled_frame(), "Wrong frame type");
516 GrowableArray<compiledVFrame*>* chunk = new GrowableArray<compiledVFrame*>(10);
517 vframe* vf = vframe::new_vframe(&deoptee, &map, current);
518 while (!vf->is_top()) {
519 assert(vf->is_compiled_frame(), "Wrong frame type");
520 chunk->push(compiledVFrame::cast(vf));
521 vf = vf->sender();
522 }
523 assert(vf->is_compiled_frame(), "Wrong frame type");
524 chunk->push(compiledVFrame::cast(vf));
525
526 bool realloc_failures = false;
527
528 #if COMPILER2_OR_JVMCI
529 bool const jvmci_enabled = JVMCI_ONLY(EnableJVMCI) NOT_JVMCI(false);
530
531 // Reallocate the non-escaping objects and restore their fields. Then
532 // relock objects if synchronization on them was eliminated.
533 if (jvmci_enabled COMPILER2_PRESENT( || (DoEscapeAnalysis && EliminateAllocations)
534 || EliminateAutoBox || EnableVectorAggressiveReboxing )) {
535 bool unused;
536 realloc_failures = rematerialize_objects(current, exec_mode, nm, deoptee, map, chunk, unused);
537 }
538 #endif // COMPILER2_OR_JVMCI
539
540 // Ensure that no safepoint is taken after pointers have been stored
541 // in fields of rematerialized objects. If a safepoint occurs from here on
542 // out the java state residing in the vframeArray will be missed.
543 // Locks may be rebaised in a safepoint.
544 NoSafepointVerifier no_safepoint;
545
546 #if COMPILER2_OR_JVMCI
547 if ((jvmci_enabled COMPILER2_PRESENT( || ((DoEscapeAnalysis || EliminateNestedLocks) && EliminateLocks) ))
548 && !EscapeBarrier::objs_are_deoptimized(current, deoptee.id())) {
549 bool unused = false;
550 restore_eliminated_locks(current, chunk, realloc_failures, deoptee, exec_mode, unused);
551 }
552 #endif // COMPILER2_OR_JVMCI
553
554 ScopeDesc* trap_scope = chunk->at(0)->scope();
555 Handle exceptionObject;
556 if (trap_scope->rethrow_exception()) {
557 #ifndef PRODUCT
558 if (PrintDeoptimizationDetails) {
559 tty->print_cr("Exception to be rethrown in the interpreter for method %s::%s at bci %d", trap_scope->method()->method_holder()->name()->as_C_string(), trap_scope->method()->name()->as_C_string(), trap_scope->bci());
560 }
561 #endif // !PRODUCT
562
563 GrowableArray<ScopeValue*>* expressions = trap_scope->expressions();
564 guarantee(expressions != nullptr && expressions->length() == 1, "should have only exception on stack");
565 guarantee(exec_mode != Unpack_exception, "rethrow_exception set with Unpack_exception");
566 ScopeValue* topOfStack = expressions->top();
567 exceptionObject = StackValue::create_stack_value(&deoptee, &map, topOfStack)->get_obj();
568 guarantee(exceptionObject() != nullptr, "exception oop can not be null");
569 }
570
571 vframeArray* array = create_vframeArray(current, deoptee, &map, chunk, realloc_failures);
572 #if COMPILER2_OR_JVMCI
573 if (realloc_failures) {
574 // This destroys all ScopedValue bindings.
575 current->clear_scopedValueBindings();
576 pop_frames_failed_reallocs(current, array);
577 }
578 #endif
579
580 assert(current->vframe_array_head() == nullptr, "Pending deopt!");
581 current->set_vframe_array_head(array);
582
583 // Now that the vframeArray has been created if we have any deferred local writes
584 // added by jvmti then we can free up that structure as the data is now in the
585 // vframeArray
586
587 JvmtiDeferredUpdates::delete_updates_for_frame(current, array->original().id());
588
589 // Compute the caller frame based on the sender sp of stub_frame and stored frame sizes info.
590 CodeBlob* cb = stub_frame.cb();
591 // Verify we have the right vframeArray
592 assert(cb->frame_size() >= 0, "Unexpected frame size");
593 intptr_t* unpack_sp = stub_frame.sp() + cb->frame_size();
594
595 // If the deopt call site is a MethodHandle invoke call site we have
596 // to adjust the unpack_sp.
597 nmethod* deoptee_nm = deoptee.cb()->as_nmethod_or_null();
598 if (deoptee_nm != nullptr && deoptee_nm->is_method_handle_return(deoptee.pc()))
599 unpack_sp = deoptee.unextended_sp();
600
601 #ifdef ASSERT
602 assert(cb->is_deoptimization_stub() ||
603 cb->is_uncommon_trap_stub() ||
604 strcmp("Stub<DeoptimizationStub.deoptimizationHandler>", cb->name()) == 0 ||
605 strcmp("Stub<UncommonTrapStub.uncommonTrapHandler>", cb->name()) == 0,
606 "unexpected code blob: %s", cb->name());
607 #endif
608
609 // This is a guarantee instead of an assert because if vframe doesn't match
610 // we will unpack the wrong deoptimized frame and wind up in strange places
611 // where it will be very difficult to figure out what went wrong. Better
612 // to die an early death here than some very obscure death later when the
613 // trail is cold.
614 guarantee(array->unextended_sp() == unpack_sp, "vframe_array_head must contain the vframeArray to unpack");
615
616 int number_of_frames = array->frames();
617
618 // Compute the vframes' sizes. Note that frame_sizes[] entries are ordered from outermost to innermost
619 // virtual activation, which is the reverse of the elements in the vframes array.
620 intptr_t* frame_sizes = NEW_C_HEAP_ARRAY(intptr_t, number_of_frames, mtCompiler);
621 // +1 because we always have an interpreter return address for the final slot.
622 address* frame_pcs = NEW_C_HEAP_ARRAY(address, number_of_frames + 1, mtCompiler);
623 int popframe_extra_args = 0;
624 // Create an interpreter return address for the stub to use as its return
625 // address so the skeletal frames are perfectly walkable
626 frame_pcs[number_of_frames] = Interpreter::deopt_entry(vtos, 0);
627
628 // PopFrame requires that the preserved incoming arguments from the recently-popped topmost
629 // activation be put back on the expression stack of the caller for reexecution
630 if (JvmtiExport::can_pop_frame() && current->popframe_forcing_deopt_reexecution()) {
631 popframe_extra_args = in_words(current->popframe_preserved_args_size_in_words());
632 }
633
634 // Find the current pc for sender of the deoptee. Since the sender may have been deoptimized
635 // itself since the deoptee vframeArray was created we must get a fresh value of the pc rather
636 // than simply use array->sender.pc(). This requires us to walk the current set of frames
637 //
638 frame deopt_sender = stub_frame.sender(&dummy_map); // First is the deoptee frame
639 deopt_sender = deopt_sender.sender(&dummy_map); // Now deoptee caller
640
641 // It's possible that the number of parameters at the call site is
642 // different than number of arguments in the callee when method
643 // handles are used. If the caller is interpreted get the real
644 // value so that the proper amount of space can be added to it's
645 // frame.
646 bool caller_was_method_handle = false;
647 if (deopt_sender.is_interpreted_frame()) {
648 methodHandle method(current, deopt_sender.interpreter_frame_method());
649 Bytecode_invoke cur(method, deopt_sender.interpreter_frame_bci());
650 if (cur.has_member_arg()) {
651 // This should cover all real-world cases. One exception is a pathological chain of
652 // MH.linkToXXX() linker calls, which only trusted code could do anyway. To handle that case, we
653 // would need to get the size from the resolved method entry. Another exception would
654 // be an invokedynamic with an adapter that is really a MethodHandle linker.
655 caller_was_method_handle = true;
656 }
657 }
658
659 //
660 // frame_sizes/frame_pcs[0] oldest frame (int or c2i)
661 // frame_sizes/frame_pcs[1] next oldest frame (int)
662 // frame_sizes/frame_pcs[n] youngest frame (int)
663 //
664 // Now a pc in frame_pcs is actually the return address to the frame's caller (a frame
665 // owns the space for the return address to it's caller). Confusing ain't it.
666 //
667 // The vframe array can address vframes with indices running from
668 // 0.._frames-1. Index 0 is the youngest frame and _frame - 1 is the oldest (root) frame.
669 // When we create the skeletal frames we need the oldest frame to be in the zero slot
670 // in the frame_sizes/frame_pcs so the assembly code can do a trivial walk.
671 // so things look a little strange in this loop.
672 //
673 int callee_parameters = 0;
674 int callee_locals = 0;
675 for (int index = 0; index < array->frames(); index++ ) {
676 // frame[number_of_frames - 1 ] = on_stack_size(youngest)
677 // frame[number_of_frames - 2 ] = on_stack_size(sender(youngest))
678 // frame[number_of_frames - 3 ] = on_stack_size(sender(sender(youngest)))
679 frame_sizes[number_of_frames - 1 - index] = BytesPerWord * array->element(index)->on_stack_size(callee_parameters,
680 callee_locals,
681 index == 0,
682 popframe_extra_args);
683 // This pc doesn't have to be perfect just good enough to identify the frame
684 // as interpreted so the skeleton frame will be walkable
685 // The correct pc will be set when the skeleton frame is completely filled out
686 // The final pc we store in the loop is wrong and will be overwritten below
687 frame_pcs[number_of_frames - 1 - index ] = Interpreter::deopt_entry(vtos, 0) - frame::pc_return_offset;
688
689 callee_parameters = array->element(index)->method()->size_of_parameters();
690 callee_locals = array->element(index)->method()->max_locals();
691 popframe_extra_args = 0;
692 }
693
694 // Compute whether the root vframe returns a float or double value.
695 BasicType return_type;
696 {
697 methodHandle method(current, array->element(0)->method());
698 Bytecode_invoke invoke = Bytecode_invoke_check(method, array->element(0)->bci());
699 return_type = invoke.is_valid() ? invoke.result_type() : T_ILLEGAL;
700 }
701
702 // Compute information for handling adapters and adjusting the frame size of the caller.
703 int caller_adjustment = 0;
704
705 // Compute the amount the oldest interpreter frame will have to adjust
706 // its caller's stack by. If the caller is a compiled frame then
707 // we pretend that the callee has no parameters so that the
708 // extension counts for the full amount of locals and not just
709 // locals-parms. This is because without a c2i adapter the parm
710 // area as created by the compiled frame will not be usable by
711 // the interpreter. (Depending on the calling convention there
712 // may not even be enough space).
713
714 // QQQ I'd rather see this pushed down into last_frame_adjust
715 // and have it take the sender (aka caller).
716
717 if (!deopt_sender.is_interpreted_frame() || caller_was_method_handle) {
718 caller_adjustment = last_frame_adjust(0, callee_locals);
719 } else if (callee_locals > callee_parameters) {
720 // The caller frame may need extending to accommodate
721 // non-parameter locals of the first unpacked interpreted frame.
722 // Compute that adjustment.
723 caller_adjustment = last_frame_adjust(callee_parameters, callee_locals);
724 }
725
726 // If the sender is deoptimized the we must retrieve the address of the handler
727 // since the frame will "magically" show the original pc before the deopt
728 // and we'd undo the deopt.
729
730 frame_pcs[0] = Continuation::is_cont_barrier_frame(deoptee) ? StubRoutines::cont_returnBarrier() : deopt_sender.raw_pc();
731 if (Continuation::is_continuation_enterSpecial(deopt_sender)) {
732 ContinuationEntry::from_frame(deopt_sender)->set_argsize(0);
733 }
734
735 assert(CodeCache::find_blob(frame_pcs[0]) != nullptr, "bad pc");
736
737 #if INCLUDE_JVMCI
738 if (exceptionObject() != nullptr) {
739 current->set_exception_oop(exceptionObject());
740 exec_mode = Unpack_exception;
741 assert(array->element(0)->rethrow_exception(), "must be");
742 }
743 #endif
744
745 if (current->frames_to_pop_failed_realloc() > 0 && exec_mode != Unpack_uncommon_trap) {
746 assert(current->has_pending_exception(), "should have thrown OOME");
747 current->set_exception_oop(current->pending_exception());
748 current->clear_pending_exception();
749 exec_mode = Unpack_exception;
750 }
751
752 #if INCLUDE_JVMCI
753 if (current->frames_to_pop_failed_realloc() > 0) {
754 current->set_pending_monitorenter(false);
755 }
756 #endif
757
758 int caller_actual_parameters = -1; // value not used except for interpreted frames, see below
759 if (deopt_sender.is_interpreted_frame()) {
760 caller_actual_parameters = callee_parameters + (caller_was_method_handle ? 1 : 0);
761 }
762
763 UnrollBlock* info = new UnrollBlock(array->frame_size() * BytesPerWord,
764 caller_adjustment * BytesPerWord,
765 caller_actual_parameters,
766 number_of_frames,
767 frame_sizes,
768 frame_pcs,
769 return_type,
770 exec_mode);
771 // On some platforms, we need a way to pass some platform dependent
772 // information to the unpacking code so the skeletal frames come out
773 // correct (initial fp value, unextended sp, ...)
774 info->set_initial_info((intptr_t) array->sender().initial_deoptimization_info());
775
776 if (array->frames() > 1) {
777 if (VerifyStack && TraceDeoptimization) {
778 tty->print_cr("Deoptimizing method containing inlining");
779 }
780 }
781
782 array->set_unroll_block(info);
783 return info;
784 }
785
786 // Called to cleanup deoptimization data structures in normal case
787 // after unpacking to stack and when stack overflow error occurs
788 void Deoptimization::cleanup_deopt_info(JavaThread *thread,
789 vframeArray *array) {
790
791 // Get array if coming from exception
792 if (array == nullptr) {
793 array = thread->vframe_array_head();
794 }
795 thread->set_vframe_array_head(nullptr);
796
797 // Free the previous UnrollBlock
798 vframeArray* old_array = thread->vframe_array_last();
799 thread->set_vframe_array_last(array);
800
801 if (old_array != nullptr) {
802 UnrollBlock* old_info = old_array->unroll_block();
803 old_array->set_unroll_block(nullptr);
804 delete old_info;
805 delete old_array;
806 }
807
808 // Deallocate any resource creating in this routine and any ResourceObjs allocated
809 // inside the vframeArray (StackValueCollections)
810
811 delete thread->deopt_mark();
812 thread->set_deopt_mark(nullptr);
813 thread->set_deopt_compiled_method(nullptr);
814
815
816 if (JvmtiExport::can_pop_frame()) {
817 // Regardless of whether we entered this routine with the pending
818 // popframe condition bit set, we should always clear it now
819 thread->clear_popframe_condition();
820 }
821
822 // unpack_frames() is called at the end of the deoptimization handler
823 // and (in C2) at the end of the uncommon trap handler. Note this fact
824 // so that an asynchronous stack walker can work again. This counter is
825 // incremented at the beginning of fetch_unroll_info() and (in C2) at
826 // the beginning of uncommon_trap().
827 thread->dec_in_deopt_handler();
828 }
829
830 // Moved from cpu directories because none of the cpus has callee save values.
831 // If a cpu implements callee save values, move this to deoptimization_<cpu>.cpp.
832 void Deoptimization::unwind_callee_save_values(frame* f, vframeArray* vframe_array) {
833
834 // This code is sort of the equivalent of C2IAdapter::setup_stack_frame back in
835 // the days we had adapter frames. When we deoptimize a situation where a
836 // compiled caller calls a compiled caller will have registers it expects
837 // to survive the call to the callee. If we deoptimize the callee the only
838 // way we can restore these registers is to have the oldest interpreter
839 // frame that we create restore these values. That is what this routine
840 // will accomplish.
841
842 // At the moment we have modified c2 to not have any callee save registers
843 // so this problem does not exist and this routine is just a place holder.
844
845 assert(f->is_interpreted_frame(), "must be interpreted");
846 }
847
848 #ifndef PRODUCT
849 #ifdef ASSERT
850 // Return true if the execution after the provided bytecode continues at the
851 // next bytecode in the code. This is not the case for gotos, returns, and
852 // throws.
853 static bool falls_through(Bytecodes::Code bc) {
854 switch (bc) {
855 case Bytecodes::_goto:
856 case Bytecodes::_goto_w:
857 case Bytecodes::_athrow:
858 case Bytecodes::_areturn:
859 case Bytecodes::_dreturn:
860 case Bytecodes::_freturn:
861 case Bytecodes::_ireturn:
862 case Bytecodes::_lreturn:
863 case Bytecodes::_jsr:
864 case Bytecodes::_ret:
865 case Bytecodes::_return:
866 case Bytecodes::_lookupswitch:
867 case Bytecodes::_tableswitch:
868 return false;
869 default:
870 return true;
871 }
872 }
873 #endif
874 #endif
875
876 // Return BasicType of value being returned
877 JRT_LEAF(BasicType, Deoptimization::unpack_frames(JavaThread* thread, int exec_mode))
878 assert(thread == JavaThread::current(), "pre-condition");
879
880 // We are already active in the special DeoptResourceMark any ResourceObj's we
881 // allocate will be freed at the end of the routine.
882
883 // JRT_LEAF methods don't normally allocate handles and there is a
884 // NoHandleMark to enforce that. It is actually safe to use Handles
885 // in a JRT_LEAF method, and sometimes desirable, but to do so we
886 // must use ResetNoHandleMark to bypass the NoHandleMark, and
887 // then use a HandleMark to ensure any Handles we do create are
888 // cleaned up in this scope.
889 ResetNoHandleMark rnhm;
890 HandleMark hm(thread);
891
892 frame stub_frame = thread->last_frame();
893
894 Continuation::notify_deopt(thread, stub_frame.sp());
895
896 // Since the frame to unpack is the top frame of this thread, the vframe_array_head
897 // must point to the vframeArray for the unpack frame.
898 vframeArray* array = thread->vframe_array_head();
899 UnrollBlock* info = array->unroll_block();
900
901 // We set the last_Java frame. But the stack isn't really parsable here. So we
902 // clear it to make sure JFR understands not to try and walk stacks from events
903 // in here.
904 intptr_t* sp = thread->frame_anchor()->last_Java_sp();
905 thread->frame_anchor()->set_last_Java_sp(nullptr);
906
907 // Unpack the interpreter frames and any adapter frame (c2 only) we might create.
908 array->unpack_to_stack(stub_frame, exec_mode, info->caller_actual_parameters());
909
910 thread->frame_anchor()->set_last_Java_sp(sp);
911
912 BasicType bt = info->return_type();
913
914 // If we have an exception pending, claim that the return type is an oop
915 // so the deopt_blob does not overwrite the exception_oop.
916
917 if (exec_mode == Unpack_exception)
918 bt = T_OBJECT;
919
920 // Cleanup thread deopt data
921 cleanup_deopt_info(thread, array);
922
923 #ifndef PRODUCT
924 if (VerifyStack) {
925 ResourceMark res_mark;
926 // Clear pending exception to not break verification code (restored afterwards)
927 PreserveExceptionMark pm(thread);
928
929 thread->validate_frame_layout();
930
931 // Verify that the just-unpacked frames match the interpreter's
932 // notions of expression stack and locals
933 vframeArray* cur_array = thread->vframe_array_last();
934 RegisterMap rm(thread,
935 RegisterMap::UpdateMap::skip,
936 RegisterMap::ProcessFrames::include,
937 RegisterMap::WalkContinuation::skip);
938 rm.set_include_argument_oops(false);
939 int callee_size_of_parameters = 0;
940 for (int frame_idx = 0; frame_idx < cur_array->frames(); frame_idx++) {
941 bool is_top_frame = (frame_idx == 0);
942 vframeArrayElement* el = cur_array->element(frame_idx);
943 frame* iframe = el->iframe();
944 guarantee(iframe->is_interpreted_frame(), "Wrong frame type");
945 methodHandle mh(thread, iframe->interpreter_frame_method());
946 bool reexecute = el->should_reexecute();
947
948 int cur_invoke_parameter_size = 0;
949 int top_frame_expression_stack_adjustment = 0;
950 int max_bci = mh->code_size();
951 BytecodeStream str(mh, iframe->interpreter_frame_bci());
952 assert(str.bci() < max_bci, "bci in interpreter frame out of bounds");
953 Bytecodes::Code cur_code = str.next();
954
955 if (!reexecute && !Bytecodes::is_invoke(cur_code)) {
956 // We can only compute OopMaps for the before state, so we need to roll forward
957 // to the next bytecode.
958 assert(is_top_frame, "must be");
959 assert(falls_through(cur_code), "must be");
960 assert(cur_code != Bytecodes::_illegal, "illegal bytecode");
961 assert(str.bci() < max_bci, "bci in interpreter frame out of bounds");
962
963 // Need to subtract off the size of the result type of
964 // the bytecode because this is not described in the
965 // debug info but returned to the interpreter in the TOS
966 // caching register
967 BasicType bytecode_result_type = Bytecodes::result_type(cur_code);
968 if (bytecode_result_type != T_ILLEGAL) {
969 top_frame_expression_stack_adjustment = type2size[bytecode_result_type];
970 }
971 assert(top_frame_expression_stack_adjustment >= 0, "stack adjustment must be positive");
972
973 cur_code = str.next();
974 // Reflect the fact that we have rolled forward and now need
975 // top_frame_expression_stack_adjustment
976 reexecute = true;
977 }
978
979 assert(cur_code != Bytecodes::_illegal, "illegal bytecode");
980 assert(str.bci() < max_bci, "bci in interpreter frame out of bounds");
981
982 // Get the oop map for this bci
983 InterpreterOopMap mask;
984 OopMapCache::compute_one_oop_map(mh, str.bci(), &mask);
985 // Check to see if we can grab the number of outgoing arguments
986 // at an uncommon trap for an invoke (where the compiler
987 // generates debug info before the invoke has executed)
988 if (Bytecodes::is_invoke(cur_code)) {
989 Bytecode_invoke invoke(mh, str.bci());
990 cur_invoke_parameter_size = invoke.size_of_parameters();
991 if (!is_top_frame && invoke.has_member_arg()) {
992 callee_size_of_parameters++;
993 }
994 }
995
996 // Verify stack depth and oops in frame
997 auto match = [&]() {
998 int iframe_expr_ssize = iframe->interpreter_frame_expression_stack_size();
999 #if INCLUDE_JVMCI
1000 if (is_top_frame && el->rethrow_exception()) {
1001 return iframe_expr_ssize == 1;
1002 }
1003 #endif
1004 // This should only be needed for C1
1005 if (is_top_frame && exec_mode == Unpack_exception && iframe_expr_ssize == 0) {
1006 return true;
1007 }
1008 if (reexecute) {
1009 int expr_ssize_before = iframe_expr_ssize + top_frame_expression_stack_adjustment;
1010 int oopmap_expr_invoke_ssize = mask.expression_stack_size() + cur_invoke_parameter_size;
1011 return expr_ssize_before == oopmap_expr_invoke_ssize;
1012 } else {
1013 int oopmap_expr_callee_ssize = mask.expression_stack_size() + callee_size_of_parameters;
1014 return iframe_expr_ssize == oopmap_expr_callee_ssize;
1015 }
1016 };
1017 if (!match()) {
1018 // Print out some information that will help us debug the problem
1019 tty->print_cr("Wrong number of expression stack elements during deoptimization");
1020 tty->print_cr(" Error occurred while verifying frame %d (0..%d, 0 is topmost)", frame_idx, cur_array->frames() - 1);
1021 tty->print_cr(" Current code %s", Bytecodes::name(cur_code));
1022 tty->print_cr(" Fabricated interpreter frame had %d expression stack elements",
1023 iframe->interpreter_frame_expression_stack_size());
1024 tty->print_cr(" Interpreter oop map had %d expression stack elements", mask.expression_stack_size());
1025 tty->print_cr(" callee_size_of_parameters = %d", callee_size_of_parameters);
1026 tty->print_cr(" top_frame_expression_stack_adjustment = %d", top_frame_expression_stack_adjustment);
1027 tty->print_cr(" exec_mode = %d", exec_mode);
1028 tty->print_cr(" original should_reexecute = %s", el->should_reexecute() ? "true" : "false");
1029 tty->print_cr(" reexecute = %s%s", reexecute ? "true" : "false",
1030 (reexecute != el->should_reexecute()) ? " (changed)" : "");
1031 #if INCLUDE_JVMCI
1032 tty->print_cr(" rethrow_exception = %s", el->rethrow_exception() ? "true" : "false");
1033 #endif
1034 tty->print_cr(" cur_invoke_parameter_size = %d", cur_invoke_parameter_size);
1035 tty->print_cr(" Thread = " INTPTR_FORMAT ", thread ID = %d", p2i(thread), thread->osthread()->thread_id());
1036 tty->print_cr(" Interpreted frames:");
1037 for (int k = 0; k < cur_array->frames(); k++) {
1038 vframeArrayElement* el = cur_array->element(k);
1039 tty->print_cr(" %s (bci %d)", el->method()->name_and_sig_as_C_string(), el->bci());
1040 }
1041 cur_array->print_on_2(tty);
1042 guarantee(false, "wrong number of expression stack elements during deopt");
1043 }
1044 VerifyOopClosure verify;
1045 iframe->oops_interpreted_do(&verify, &rm, false);
1046 callee_size_of_parameters = mh->size_of_parameters();
1047 }
1048 }
1049 #endif // !PRODUCT
1050
1051 return bt;
1052 JRT_END
1053
1054 class DeoptimizeMarkedHandshakeClosure : public HandshakeClosure {
1055 public:
1056 DeoptimizeMarkedHandshakeClosure() : HandshakeClosure("Deoptimize") {}
1057 void do_thread(Thread* thread) {
1058 JavaThread* jt = JavaThread::cast(thread);
1059 jt->deoptimize_marked_methods();
1060 }
1061 };
1062
1063 void Deoptimization::deoptimize_all_marked() {
1064 ResourceMark rm;
1065
1066 // Make the dependent methods not entrant
1067 CodeCache::make_marked_nmethods_deoptimized();
1068
1069 DeoptimizeMarkedHandshakeClosure deopt;
1070 if (SafepointSynchronize::is_at_safepoint()) {
1071 Threads::java_threads_do(&deopt);
1072 } else {
1073 Handshake::execute(&deopt);
1074 }
1075 }
1076
1077 Deoptimization::DeoptAction Deoptimization::_unloaded_action
1078 = Deoptimization::Action_reinterpret;
1079
1080 #if INCLUDE_JVMCI
1081 template<typename CacheType>
1082 class BoxCacheBase : public CHeapObj<mtCompiler> {
1083 protected:
1084 static InstanceKlass* find_cache_klass(Thread* thread, Symbol* klass_name) {
1085 ResourceMark rm(thread);
1086 char* klass_name_str = klass_name->as_C_string();
1087 InstanceKlass* ik = SystemDictionary::find_instance_klass(thread, klass_name, Handle());
1088 guarantee(ik != nullptr, "%s must be loaded", klass_name_str);
1089 if (!ik->is_in_error_state()) {
1090 guarantee(ik->is_initialized(), "%s must be initialized", klass_name_str);
1091 CacheType::compute_offsets(ik);
1092 }
1093 return ik;
1094 }
1095 };
1096
1097 template<typename PrimitiveType, typename CacheType, typename BoxType> class BoxCache : public BoxCacheBase<CacheType> {
1098 PrimitiveType _low;
1099 PrimitiveType _high;
1100 jobject _cache;
1101 protected:
1102 static BoxCache<PrimitiveType, CacheType, BoxType> *_singleton;
1103 BoxCache(Thread* thread) {
1104 InstanceKlass* ik = BoxCacheBase<CacheType>::find_cache_klass(thread, CacheType::symbol());
1105 if (ik->is_in_error_state()) {
1106 _low = 1;
1107 _high = 0;
1108 _cache = nullptr;
1109 } else {
1110 objArrayOop cache = CacheType::cache(ik);
1111 assert(cache->length() > 0, "Empty cache");
1112 _low = BoxType::value(cache->obj_at(0));
1113 _high = checked_cast<PrimitiveType>(_low + cache->length() - 1);
1114 _cache = JNIHandles::make_global(Handle(thread, cache));
1115 }
1116 }
1117 ~BoxCache() {
1118 JNIHandles::destroy_global(_cache);
1119 }
1120 public:
1121 static BoxCache<PrimitiveType, CacheType, BoxType>* singleton(Thread* thread) {
1122 if (_singleton == nullptr) {
1123 BoxCache<PrimitiveType, CacheType, BoxType>* s = new BoxCache<PrimitiveType, CacheType, BoxType>(thread);
1124 if (!Atomic::replace_if_null(&_singleton, s)) {
1125 delete s;
1126 }
1127 }
1128 return _singleton;
1129 }
1130 oop lookup(PrimitiveType value) {
1131 if (_low <= value && value <= _high) {
1132 int offset = checked_cast<int>(value - _low);
1133 return objArrayOop(JNIHandles::resolve_non_null(_cache))->obj_at(offset);
1134 }
1135 return nullptr;
1136 }
1137 oop lookup_raw(intptr_t raw_value, bool& cache_init_error) {
1138 if (_cache == nullptr) {
1139 cache_init_error = true;
1140 return nullptr;
1141 }
1142 // Have to cast to avoid little/big-endian problems.
1143 if (sizeof(PrimitiveType) > sizeof(jint)) {
1144 jlong value = (jlong)raw_value;
1145 return lookup(value);
1146 }
1147 PrimitiveType value = (PrimitiveType)*((jint*)&raw_value);
1148 return lookup(value);
1149 }
1150 };
1151
1152 typedef BoxCache<jint, java_lang_Integer_IntegerCache, java_lang_Integer> IntegerBoxCache;
1153 typedef BoxCache<jlong, java_lang_Long_LongCache, java_lang_Long> LongBoxCache;
1154 typedef BoxCache<jchar, java_lang_Character_CharacterCache, java_lang_Character> CharacterBoxCache;
1155 typedef BoxCache<jshort, java_lang_Short_ShortCache, java_lang_Short> ShortBoxCache;
1156 typedef BoxCache<jbyte, java_lang_Byte_ByteCache, java_lang_Byte> ByteBoxCache;
1157
1158 template<> BoxCache<jint, java_lang_Integer_IntegerCache, java_lang_Integer>* BoxCache<jint, java_lang_Integer_IntegerCache, java_lang_Integer>::_singleton = nullptr;
1159 template<> BoxCache<jlong, java_lang_Long_LongCache, java_lang_Long>* BoxCache<jlong, java_lang_Long_LongCache, java_lang_Long>::_singleton = nullptr;
1160 template<> BoxCache<jchar, java_lang_Character_CharacterCache, java_lang_Character>* BoxCache<jchar, java_lang_Character_CharacterCache, java_lang_Character>::_singleton = nullptr;
1161 template<> BoxCache<jshort, java_lang_Short_ShortCache, java_lang_Short>* BoxCache<jshort, java_lang_Short_ShortCache, java_lang_Short>::_singleton = nullptr;
1162 template<> BoxCache<jbyte, java_lang_Byte_ByteCache, java_lang_Byte>* BoxCache<jbyte, java_lang_Byte_ByteCache, java_lang_Byte>::_singleton = nullptr;
1163
1164 class BooleanBoxCache : public BoxCacheBase<java_lang_Boolean> {
1165 jobject _true_cache;
1166 jobject _false_cache;
1167 protected:
1168 static BooleanBoxCache *_singleton;
1169 BooleanBoxCache(Thread *thread) {
1170 InstanceKlass* ik = find_cache_klass(thread, java_lang_Boolean::symbol());
1171 if (ik->is_in_error_state()) {
1172 _true_cache = nullptr;
1173 _false_cache = nullptr;
1174 } else {
1175 _true_cache = JNIHandles::make_global(Handle(thread, java_lang_Boolean::get_TRUE(ik)));
1176 _false_cache = JNIHandles::make_global(Handle(thread, java_lang_Boolean::get_FALSE(ik)));
1177 }
1178 }
1179 ~BooleanBoxCache() {
1180 JNIHandles::destroy_global(_true_cache);
1181 JNIHandles::destroy_global(_false_cache);
1182 }
1183 public:
1184 static BooleanBoxCache* singleton(Thread* thread) {
1185 if (_singleton == nullptr) {
1186 BooleanBoxCache* s = new BooleanBoxCache(thread);
1187 if (!Atomic::replace_if_null(&_singleton, s)) {
1188 delete s;
1189 }
1190 }
1191 return _singleton;
1192 }
1193 oop lookup_raw(intptr_t raw_value, bool& cache_in_error) {
1194 if (_true_cache == nullptr) {
1195 cache_in_error = true;
1196 return nullptr;
1197 }
1198 // Have to cast to avoid little/big-endian problems.
1199 jboolean value = (jboolean)*((jint*)&raw_value);
1200 return lookup(value);
1201 }
1202 oop lookup(jboolean value) {
1203 if (value != 0) {
1204 return JNIHandles::resolve_non_null(_true_cache);
1205 }
1206 return JNIHandles::resolve_non_null(_false_cache);
1207 }
1208 };
1209
1210 BooleanBoxCache* BooleanBoxCache::_singleton = nullptr;
1211
1212 oop Deoptimization::get_cached_box(AutoBoxObjectValue* bv, frame* fr, RegisterMap* reg_map, bool& cache_init_error, TRAPS) {
1213 Klass* k = java_lang_Class::as_Klass(bv->klass()->as_ConstantOopReadValue()->value()());
1214 BasicType box_type = vmClasses::box_klass_type(k);
1215 if (box_type != T_OBJECT) {
1216 StackValue* value = StackValue::create_stack_value(fr, reg_map, bv->field_at(box_type == T_LONG ? 1 : 0));
1217 switch(box_type) {
1218 case T_INT: return IntegerBoxCache::singleton(THREAD)->lookup_raw(value->get_intptr(), cache_init_error);
1219 case T_CHAR: return CharacterBoxCache::singleton(THREAD)->lookup_raw(value->get_intptr(), cache_init_error);
1220 case T_SHORT: return ShortBoxCache::singleton(THREAD)->lookup_raw(value->get_intptr(), cache_init_error);
1221 case T_BYTE: return ByteBoxCache::singleton(THREAD)->lookup_raw(value->get_intptr(), cache_init_error);
1222 case T_BOOLEAN: return BooleanBoxCache::singleton(THREAD)->lookup_raw(value->get_intptr(), cache_init_error);
1223 case T_LONG: return LongBoxCache::singleton(THREAD)->lookup_raw(value->get_intptr(), cache_init_error);
1224 default:;
1225 }
1226 }
1227 return nullptr;
1228 }
1229 #endif // INCLUDE_JVMCI
1230
1231 #if COMPILER2_OR_JVMCI
1232 bool Deoptimization::realloc_objects(JavaThread* thread, frame* fr, RegisterMap* reg_map, GrowableArray<ScopeValue*>* objects, TRAPS) {
1233 Handle pending_exception(THREAD, thread->pending_exception());
1234 const char* exception_file = thread->exception_file();
1235 int exception_line = thread->exception_line();
1236 thread->clear_pending_exception();
1237
1238 bool failures = false;
1239
1240 for (int i = 0; i < objects->length(); i++) {
1241 assert(objects->at(i)->is_object(), "invalid debug information");
1242 ObjectValue* sv = (ObjectValue*) objects->at(i);
1243
1244 Klass* k = java_lang_Class::as_Klass(sv->klass()->as_ConstantOopReadValue()->value()());
1245 oop obj = nullptr;
1246
1247 bool cache_init_error = false;
1248 if (k->is_instance_klass()) {
1249 #if INCLUDE_JVMCI
1250 nmethod* nm = fr->cb()->as_nmethod_or_null();
1251 if (nm->is_compiled_by_jvmci() && sv->is_auto_box()) {
1252 AutoBoxObjectValue* abv = (AutoBoxObjectValue*) sv;
1253 obj = get_cached_box(abv, fr, reg_map, cache_init_error, THREAD);
1254 if (obj != nullptr) {
1255 // Set the flag to indicate the box came from a cache, so that we can skip the field reassignment for it.
1256 abv->set_cached(true);
1257 } else if (cache_init_error) {
1258 // Results in an OOME which is valid (as opposed to a class initialization error)
1259 // and is fine for the rare case a cache initialization failing.
1260 failures = true;
1261 }
1262 }
1263 #endif // INCLUDE_JVMCI
1264
1265 InstanceKlass* ik = InstanceKlass::cast(k);
1266 if (obj == nullptr && !cache_init_error) {
1267 InternalOOMEMark iom(THREAD);
1268 if (EnableVectorSupport && VectorSupport::is_vector(ik)) {
1269 obj = VectorSupport::allocate_vector(ik, fr, reg_map, sv, THREAD);
1270 } else {
1271 obj = ik->allocate_instance(THREAD);
1272 }
1273 }
1274 } else if (k->is_typeArray_klass()) {
1275 TypeArrayKlass* ak = TypeArrayKlass::cast(k);
1276 assert(sv->field_size() % type2size[ak->element_type()] == 0, "non-integral array length");
1277 int len = sv->field_size() / type2size[ak->element_type()];
1278 InternalOOMEMark iom(THREAD);
1279 obj = ak->allocate_instance(len, THREAD);
1280 } else if (k->is_objArray_klass()) {
1281 ObjArrayKlass* ak = ObjArrayKlass::cast(k);
1282 InternalOOMEMark iom(THREAD);
1283 obj = ak->allocate_instance(sv->field_size(), THREAD);
1284 }
1285
1286 if (obj == nullptr) {
1287 failures = true;
1288 }
1289
1290 assert(sv->value().is_null(), "redundant reallocation");
1291 assert(obj != nullptr || HAS_PENDING_EXCEPTION || cache_init_error, "allocation should succeed or we should get an exception");
1292 CLEAR_PENDING_EXCEPTION;
1293 sv->set_value(obj);
1294 }
1295
1296 if (failures) {
1297 THROW_OOP_(Universe::out_of_memory_error_realloc_objects(), failures);
1298 } else if (pending_exception.not_null()) {
1299 thread->set_pending_exception(pending_exception(), exception_file, exception_line);
1300 }
1301
1302 return failures;
1303 }
1304
1305 #if INCLUDE_JVMCI
1306 /**
1307 * For primitive types whose kind gets "erased" at runtime (shorts become stack ints),
1308 * we need to somehow be able to recover the actual kind to be able to write the correct
1309 * amount of bytes.
1310 * For that purpose, this method assumes that, for an entry spanning n bytes at index i,
1311 * the entries at index n + 1 to n + i are 'markers'.
1312 * For example, if we were writing a short at index 4 of a byte array of size 8, the
1313 * expected form of the array would be:
1314 *
1315 * {b0, b1, b2, b3, INT, marker, b6, b7}
1316 *
1317 * Thus, in order to get back the size of the entry, we simply need to count the number
1318 * of marked entries
1319 *
1320 * @param virtualArray the virtualized byte array
1321 * @param i index of the virtual entry we are recovering
1322 * @return The number of bytes the entry spans
1323 */
1324 static int count_number_of_bytes_for_entry(ObjectValue *virtualArray, int i) {
1325 int index = i;
1326 while (++index < virtualArray->field_size() &&
1327 virtualArray->field_at(index)->is_marker()) {}
1328 return index - i;
1329 }
1330
1331 /**
1332 * If there was a guarantee for byte array to always start aligned to a long, we could
1333 * do a simple check on the parity of the index. Unfortunately, that is not always the
1334 * case. Thus, we check alignment of the actual address we are writing to.
1335 * In the unlikely case index 0 is 5-aligned for example, it would then be possible to
1336 * write a long to index 3.
1337 */
1338 static jbyte* check_alignment_get_addr(typeArrayOop obj, int index, int expected_alignment) {
1339 jbyte* res = obj->byte_at_addr(index);
1340 assert((((intptr_t) res) % expected_alignment) == 0, "Non-aligned write");
1341 return res;
1342 }
1343
1344 static void byte_array_put(typeArrayOop obj, StackValue* value, int index, int byte_count) {
1345 switch (byte_count) {
1346 case 1:
1347 obj->byte_at_put(index, (jbyte) value->get_jint());
1348 break;
1349 case 2:
1350 *((jshort *) check_alignment_get_addr(obj, index, 2)) = (jshort) value->get_jint();
1351 break;
1352 case 4:
1353 *((jint *) check_alignment_get_addr(obj, index, 4)) = value->get_jint();
1354 break;
1355 case 8:
1356 *((jlong *) check_alignment_get_addr(obj, index, 8)) = (jlong) value->get_intptr();
1357 break;
1358 default:
1359 ShouldNotReachHere();
1360 }
1361 }
1362 #endif // INCLUDE_JVMCI
1363
1364
1365 // restore elements of an eliminated type array
1366 void Deoptimization::reassign_type_array_elements(frame* fr, RegisterMap* reg_map, ObjectValue* sv, typeArrayOop obj, BasicType type) {
1367 int index = 0;
1368
1369 for (int i = 0; i < sv->field_size(); i++) {
1370 StackValue* value = StackValue::create_stack_value(fr, reg_map, sv->field_at(i));
1371 switch(type) {
1372 case T_LONG: case T_DOUBLE: {
1373 assert(value->type() == T_INT, "Agreement.");
1374 StackValue* low =
1375 StackValue::create_stack_value(fr, reg_map, sv->field_at(++i));
1376 #ifdef _LP64
1377 jlong res = (jlong)low->get_intptr();
1378 #else
1379 jlong res = jlong_from(value->get_jint(), low->get_jint());
1380 #endif
1381 obj->long_at_put(index, res);
1382 break;
1383 }
1384
1385 case T_INT: case T_FLOAT: { // 4 bytes.
1386 assert(value->type() == T_INT, "Agreement.");
1387 bool big_value = false;
1388 if (i + 1 < sv->field_size() && type == T_INT) {
1389 if (sv->field_at(i)->is_location()) {
1390 Location::Type type = ((LocationValue*) sv->field_at(i))->location().type();
1391 if (type == Location::dbl || type == Location::lng) {
1392 big_value = true;
1393 }
1394 } else if (sv->field_at(i)->is_constant_int()) {
1395 ScopeValue* next_scope_field = sv->field_at(i + 1);
1396 if (next_scope_field->is_constant_long() || next_scope_field->is_constant_double()) {
1397 big_value = true;
1398 }
1399 }
1400 }
1401
1402 if (big_value) {
1403 StackValue* low = StackValue::create_stack_value(fr, reg_map, sv->field_at(++i));
1404 #ifdef _LP64
1405 jlong res = (jlong)low->get_intptr();
1406 #else
1407 jlong res = jlong_from(value->get_jint(), low->get_jint());
1408 #endif
1409 obj->int_at_put(index, *(jint*)&res);
1410 obj->int_at_put(++index, *((jint*)&res + 1));
1411 } else {
1412 obj->int_at_put(index, value->get_jint());
1413 }
1414 break;
1415 }
1416
1417 case T_SHORT:
1418 assert(value->type() == T_INT, "Agreement.");
1419 obj->short_at_put(index, (jshort)value->get_jint());
1420 break;
1421
1422 case T_CHAR:
1423 assert(value->type() == T_INT, "Agreement.");
1424 obj->char_at_put(index, (jchar)value->get_jint());
1425 break;
1426
1427 case T_BYTE: {
1428 assert(value->type() == T_INT, "Agreement.");
1429 #if INCLUDE_JVMCI
1430 // The value we get is erased as a regular int. We will need to find its actual byte count 'by hand'.
1431 int byte_count = count_number_of_bytes_for_entry(sv, i);
1432 byte_array_put(obj, value, index, byte_count);
1433 // According to byte_count contract, the values from i + 1 to i + byte_count are illegal values. Skip.
1434 i += byte_count - 1; // Balance the loop counter.
1435 index += byte_count;
1436 // index has been updated so continue at top of loop
1437 continue;
1438 #else
1439 obj->byte_at_put(index, (jbyte)value->get_jint());
1440 break;
1441 #endif // INCLUDE_JVMCI
1442 }
1443
1444 case T_BOOLEAN: {
1445 assert(value->type() == T_INT, "Agreement.");
1446 obj->bool_at_put(index, (jboolean)value->get_jint());
1447 break;
1448 }
1449
1450 default:
1451 ShouldNotReachHere();
1452 }
1453 index++;
1454 }
1455 }
1456
1457 // restore fields of an eliminated object array
1458 void Deoptimization::reassign_object_array_elements(frame* fr, RegisterMap* reg_map, ObjectValue* sv, objArrayOop obj) {
1459 for (int i = 0; i < sv->field_size(); i++) {
1460 StackValue* value = StackValue::create_stack_value(fr, reg_map, sv->field_at(i));
1461 assert(value->type() == T_OBJECT, "object element expected");
1462 obj->obj_at_put(i, value->get_obj()());
1463 }
1464 }
1465
1466 class ReassignedField {
1467 public:
1468 int _offset;
1469 BasicType _type;
1470 public:
1471 ReassignedField() {
1472 _offset = 0;
1473 _type = T_ILLEGAL;
1474 }
1475 };
1476
1477 // Gets the fields of `klass` that are eliminated by escape analysis and need to be reassigned
1478 static GrowableArray<ReassignedField>* get_reassigned_fields(InstanceKlass* klass, GrowableArray<ReassignedField>* fields, bool is_jvmci) {
1479 InstanceKlass* super = klass->superklass();
1480 if (super != nullptr) {
1481 get_reassigned_fields(super, fields, is_jvmci);
1482 }
1483 for (AllFieldStream fs(klass); !fs.done(); fs.next()) {
1484 if (!fs.access_flags().is_static() && (is_jvmci || !fs.field_flags().is_injected())) {
1485 ReassignedField field;
1486 field._offset = fs.offset();
1487 field._type = Signature::basic_type(fs.signature());
1488 fields->append(field);
1489 }
1490 }
1491 return fields;
1492 }
1493
1494 // Restore fields of an eliminated instance object employing the same field order used by the compiler.
1495 static int reassign_fields_by_klass(InstanceKlass* klass, frame* fr, RegisterMap* reg_map, ObjectValue* sv, int svIndex, oop obj, bool is_jvmci) {
1496 GrowableArray<ReassignedField>* fields = get_reassigned_fields(klass, new GrowableArray<ReassignedField>(), is_jvmci);
1497 for (int i = 0; i < fields->length(); i++) {
1498 ScopeValue* scope_field = sv->field_at(svIndex);
1499 StackValue* value = StackValue::create_stack_value(fr, reg_map, scope_field);
1500 int offset = fields->at(i)._offset;
1501 BasicType type = fields->at(i)._type;
1502 switch (type) {
1503 case T_OBJECT: case T_ARRAY:
1504 assert(value->type() == T_OBJECT, "Agreement.");
1505 obj->obj_field_put(offset, value->get_obj()());
1506 break;
1507
1508 case T_INT: case T_FLOAT: { // 4 bytes.
1509 assert(value->type() == T_INT, "Agreement.");
1510 bool big_value = false;
1511 if (i+1 < fields->length() && fields->at(i+1)._type == T_INT) {
1512 if (scope_field->is_location()) {
1513 Location::Type type = ((LocationValue*) scope_field)->location().type();
1514 if (type == Location::dbl || type == Location::lng) {
1515 big_value = true;
1516 }
1517 }
1518 if (scope_field->is_constant_int()) {
1519 ScopeValue* next_scope_field = sv->field_at(svIndex + 1);
1520 if (next_scope_field->is_constant_long() || next_scope_field->is_constant_double()) {
1521 big_value = true;
1522 }
1523 }
1524 }
1525
1526 if (big_value) {
1527 i++;
1528 assert(i < fields->length(), "second T_INT field needed");
1529 assert(fields->at(i)._type == T_INT, "T_INT field needed");
1530 } else {
1531 obj->int_field_put(offset, value->get_jint());
1532 break;
1533 }
1534 }
1535 /* no break */
1536
1537 case T_LONG: case T_DOUBLE: {
1538 assert(value->type() == T_INT, "Agreement.");
1539 StackValue* low = StackValue::create_stack_value(fr, reg_map, sv->field_at(++svIndex));
1540 #ifdef _LP64
1541 jlong res = (jlong)low->get_intptr();
1542 #else
1543 jlong res = jlong_from(value->get_jint(), low->get_jint());
1544 #endif
1545 obj->long_field_put(offset, res);
1546 break;
1547 }
1548
1549 case T_SHORT:
1550 assert(value->type() == T_INT, "Agreement.");
1551 obj->short_field_put(offset, (jshort)value->get_jint());
1552 break;
1553
1554 case T_CHAR:
1555 assert(value->type() == T_INT, "Agreement.");
1556 obj->char_field_put(offset, (jchar)value->get_jint());
1557 break;
1558
1559 case T_BYTE:
1560 assert(value->type() == T_INT, "Agreement.");
1561 obj->byte_field_put(offset, (jbyte)value->get_jint());
1562 break;
1563
1564 case T_BOOLEAN:
1565 assert(value->type() == T_INT, "Agreement.");
1566 obj->bool_field_put(offset, (jboolean)value->get_jint());
1567 break;
1568
1569 default:
1570 ShouldNotReachHere();
1571 }
1572 svIndex++;
1573 }
1574 return svIndex;
1575 }
1576
1577 // restore fields of all eliminated objects and arrays
1578 void Deoptimization::reassign_fields(frame* fr, RegisterMap* reg_map, GrowableArray<ScopeValue*>* objects, bool realloc_failures, bool is_jvmci) {
1579 for (int i = 0; i < objects->length(); i++) {
1580 assert(objects->at(i)->is_object(), "invalid debug information");
1581 ObjectValue* sv = (ObjectValue*) objects->at(i);
1582 Klass* k = java_lang_Class::as_Klass(sv->klass()->as_ConstantOopReadValue()->value()());
1583 Handle obj = sv->value();
1584 assert(obj.not_null() || realloc_failures, "reallocation was missed");
1585 #ifndef PRODUCT
1586 if (PrintDeoptimizationDetails) {
1587 tty->print_cr("reassign fields for object of type %s!", k->name()->as_C_string());
1588 }
1589 #endif // !PRODUCT
1590
1591 if (obj.is_null()) {
1592 continue;
1593 }
1594
1595 #if INCLUDE_JVMCI
1596 // Don't reassign fields of boxes that came from a cache. Caches may be in CDS.
1597 if (sv->is_auto_box() && ((AutoBoxObjectValue*) sv)->is_cached()) {
1598 continue;
1599 }
1600 #endif // INCLUDE_JVMCI
1601 if (EnableVectorSupport && VectorSupport::is_vector(k)) {
1602 assert(sv->field_size() == 1, "%s not a vector", k->name()->as_C_string());
1603 ScopeValue* payload = sv->field_at(0);
1604 if (payload->is_location() &&
1605 payload->as_LocationValue()->location().type() == Location::vector) {
1606 #ifndef PRODUCT
1607 if (PrintDeoptimizationDetails) {
1608 tty->print_cr("skip field reassignment for this vector - it should be assigned already");
1609 if (Verbose) {
1610 Handle obj = sv->value();
1611 k->oop_print_on(obj(), tty);
1612 }
1613 }
1614 #endif // !PRODUCT
1615 continue; // Such vector's value was already restored in VectorSupport::allocate_vector().
1616 }
1617 // Else fall-through to do assignment for scalar-replaced boxed vector representation
1618 // which could be restored after vector object allocation.
1619 }
1620 if (k->is_instance_klass()) {
1621 InstanceKlass* ik = InstanceKlass::cast(k);
1622 reassign_fields_by_klass(ik, fr, reg_map, sv, 0, obj(), is_jvmci);
1623 } else if (k->is_typeArray_klass()) {
1624 TypeArrayKlass* ak = TypeArrayKlass::cast(k);
1625 reassign_type_array_elements(fr, reg_map, sv, (typeArrayOop) obj(), ak->element_type());
1626 } else if (k->is_objArray_klass()) {
1627 reassign_object_array_elements(fr, reg_map, sv, (objArrayOop) obj());
1628 }
1629 }
1630 // These objects may escape when we return to Interpreter after deoptimization.
1631 // We need barrier so that stores that initialize these objects can't be reordered
1632 // with subsequent stores that make these objects accessible by other threads.
1633 OrderAccess::storestore();
1634 }
1635
1636
1637 // relock objects for which synchronization was eliminated
1638 bool Deoptimization::relock_objects(JavaThread* thread, GrowableArray<MonitorInfo*>* monitors,
1639 JavaThread* deoptee_thread, frame& fr, int exec_mode, bool realloc_failures) {
1640 bool relocked_objects = false;
1641 for (int i = 0; i < monitors->length(); i++) {
1642 MonitorInfo* mon_info = monitors->at(i);
1643 if (mon_info->eliminated()) {
1644 assert(!mon_info->owner_is_scalar_replaced() || realloc_failures, "reallocation was missed");
1645 relocked_objects = true;
1646 if (!mon_info->owner_is_scalar_replaced()) {
1647 Handle obj(thread, mon_info->owner());
1648 markWord mark = obj->mark();
1649 if (exec_mode == Unpack_none) {
1650 if (LockingMode == LM_LEGACY && mark.has_locker() && fr.sp() > (intptr_t*)mark.locker()) {
1651 // With exec_mode == Unpack_none obj may be thread local and locked in
1652 // a callee frame. Make the lock in the callee a recursive lock and restore the displaced header.
1653 markWord dmw = mark.displaced_mark_helper();
1654 mark.locker()->set_displaced_header(markWord::encode((BasicLock*) nullptr));
1655 obj->set_mark(dmw);
1656 }
1657 if (mark.has_monitor()) {
1658 // defer relocking if the deoptee thread is currently waiting for obj
1659 ObjectMonitor* waiting_monitor = deoptee_thread->current_waiting_monitor();
1660 if (waiting_monitor != nullptr && waiting_monitor->object() == obj()) {
1661 assert(fr.is_deoptimized_frame(), "frame must be scheduled for deoptimization");
1662 if (LockingMode == LM_LEGACY) {
1663 mon_info->lock()->set_displaced_header(markWord::unused_mark());
1664 } else if (UseObjectMonitorTable) {
1665 mon_info->lock()->clear_object_monitor_cache();
1666 }
1667 #ifdef ASSERT
1668 else {
1669 assert(LockingMode == LM_MONITOR || !UseObjectMonitorTable, "must be");
1670 mon_info->lock()->set_bad_metadata_deopt();
1671 }
1672 #endif
1673 JvmtiDeferredUpdates::inc_relock_count_after_wait(deoptee_thread);
1674 continue;
1675 }
1676 }
1677 }
1678 BasicLock* lock = mon_info->lock();
1679 if (LockingMode == LM_LIGHTWEIGHT) {
1680 // We have lost information about the correct state of the lock stack.
1681 // Entering may create an invalid lock stack. Inflate the lock if it
1682 // was fast_locked to restore the valid lock stack.
1683 if (UseObjectMonitorTable) {
1684 // UseObjectMonitorTable expects the BasicLock cache to be either a
1685 // valid ObjectMonitor* or nullptr. Right now it is garbage, set it
1686 // to nullptr.
1687 lock->clear_object_monitor_cache();
1688 }
1689 ObjectSynchronizer::enter_for(obj, lock, deoptee_thread);
1690 if (deoptee_thread->lock_stack().contains(obj())) {
1691 LightweightSynchronizer::inflate_fast_locked_object(obj(), ObjectSynchronizer::InflateCause::inflate_cause_vm_internal,
1692 deoptee_thread, thread);
1693 }
1694 assert(mon_info->owner()->is_locked(), "object must be locked now");
1695 assert(obj->mark().has_monitor(), "must be");
1696 assert(!deoptee_thread->lock_stack().contains(obj()), "must be");
1697 assert(ObjectSynchronizer::read_monitor(thread, obj(), obj->mark())->has_owner(deoptee_thread), "must be");
1698 } else {
1699 ObjectSynchronizer::enter_for(obj, lock, deoptee_thread);
1700 assert(mon_info->owner()->is_locked(), "object must be locked now");
1701 }
1702 }
1703 }
1704 }
1705 return relocked_objects;
1706 }
1707 #endif // COMPILER2_OR_JVMCI
1708
1709 vframeArray* Deoptimization::create_vframeArray(JavaThread* thread, frame fr, RegisterMap *reg_map, GrowableArray<compiledVFrame*>* chunk, bool realloc_failures) {
1710 Events::log_deopt_message(thread, "DEOPT PACKING pc=" INTPTR_FORMAT " sp=" INTPTR_FORMAT, p2i(fr.pc()), p2i(fr.sp()));
1711
1712 // Register map for next frame (used for stack crawl). We capture
1713 // the state of the deopt'ing frame's caller. Thus if we need to
1714 // stuff a C2I adapter we can properly fill in the callee-save
1715 // register locations.
1716 frame caller = fr.sender(reg_map);
1717 int frame_size = pointer_delta_as_int(caller.sp(), fr.sp());
1718
1719 frame sender = caller;
1720
1721 // Since the Java thread being deoptimized will eventually adjust it's own stack,
1722 // the vframeArray containing the unpacking information is allocated in the C heap.
1723 // For Compiler1, the caller of the deoptimized frame is saved for use by unpack_frames().
1724 vframeArray* array = vframeArray::allocate(thread, frame_size, chunk, reg_map, sender, caller, fr, realloc_failures);
1725
1726 // Compare the vframeArray to the collected vframes
1727 assert(array->structural_compare(thread, chunk), "just checking");
1728
1729 if (TraceDeoptimization) {
1730 ResourceMark rm;
1731 stringStream st;
1732 st.print_cr("DEOPT PACKING thread=" INTPTR_FORMAT " vframeArray=" INTPTR_FORMAT, p2i(thread), p2i(array));
1733 st.print(" ");
1734 fr.print_on(&st);
1735 st.print_cr(" Virtual frames (innermost/newest first):");
1736 for (int index = 0; index < chunk->length(); index++) {
1737 compiledVFrame* vf = chunk->at(index);
1738 int bci = vf->raw_bci();
1739 const char* code_name;
1740 if (bci == SynchronizationEntryBCI) {
1741 code_name = "sync entry";
1742 } else {
1743 Bytecodes::Code code = vf->method()->code_at(bci);
1744 code_name = Bytecodes::name(code);
1745 }
1746
1747 st.print(" VFrame %d (" INTPTR_FORMAT ")", index, p2i(vf));
1748 st.print(" - %s", vf->method()->name_and_sig_as_C_string());
1749 st.print(" - %s", code_name);
1750 st.print_cr(" @ bci=%d ", bci);
1751 }
1752 tty->print_raw(st.freeze());
1753 tty->cr();
1754 }
1755
1756 return array;
1757 }
1758
1759 #if COMPILER2_OR_JVMCI
1760 void Deoptimization::pop_frames_failed_reallocs(JavaThread* thread, vframeArray* array) {
1761 // Reallocation of some scalar replaced objects failed. Record
1762 // that we need to pop all the interpreter frames for the
1763 // deoptimized compiled frame.
1764 assert(thread->frames_to_pop_failed_realloc() == 0, "missed frames to pop?");
1765 thread->set_frames_to_pop_failed_realloc(array->frames());
1766 // Unlock all monitors here otherwise the interpreter will see a
1767 // mix of locked and unlocked monitors (because of failed
1768 // reallocations of synchronized objects) and be confused.
1769 for (int i = 0; i < array->frames(); i++) {
1770 MonitorChunk* monitors = array->element(i)->monitors();
1771 if (monitors != nullptr) {
1772 // Unlock in reverse order starting from most nested monitor.
1773 for (int j = (monitors->number_of_monitors() - 1); j >= 0; j--) {
1774 BasicObjectLock* src = monitors->at(j);
1775 if (src->obj() != nullptr) {
1776 ObjectSynchronizer::exit(src->obj(), src->lock(), thread);
1777 }
1778 }
1779 array->element(i)->free_monitors();
1780 #ifdef ASSERT
1781 array->element(i)->set_removed_monitors();
1782 #endif
1783 }
1784 }
1785 }
1786 #endif
1787
1788 void Deoptimization::deoptimize_single_frame(JavaThread* thread, frame fr, Deoptimization::DeoptReason reason) {
1789 assert(fr.can_be_deoptimized(), "checking frame type");
1790
1791 gather_statistics(reason, Action_none, Bytecodes::_illegal);
1792
1793 if (LogCompilation && xtty != nullptr) {
1794 nmethod* nm = fr.cb()->as_nmethod_or_null();
1795 assert(nm != nullptr, "only compiled methods can deopt");
1796
1797 ttyLocker ttyl;
1798 xtty->begin_head("deoptimized thread='%zu' reason='%s' pc='" INTPTR_FORMAT "'",(uintx)thread->osthread()->thread_id(), trap_reason_name(reason), p2i(fr.pc()));
1799 nm->log_identity(xtty);
1800 xtty->end_head();
1801 for (ScopeDesc* sd = nm->scope_desc_at(fr.pc()); ; sd = sd->sender()) {
1802 xtty->begin_elem("jvms bci='%d'", sd->bci());
1803 xtty->method(sd->method());
1804 xtty->end_elem();
1805 if (sd->is_top()) break;
1806 }
1807 xtty->tail("deoptimized");
1808 }
1809
1810 Continuation::notify_deopt(thread, fr.sp());
1811
1812 // Patch the compiled method so that when execution returns to it we will
1813 // deopt the execution state and return to the interpreter.
1814 fr.deoptimize(thread);
1815 }
1816
1817 void Deoptimization::deoptimize(JavaThread* thread, frame fr, DeoptReason reason) {
1818 // Deoptimize only if the frame comes from compile code.
1819 // Do not deoptimize the frame which is already patched
1820 // during the execution of the loops below.
1821 if (!fr.is_compiled_frame() || fr.is_deoptimized_frame()) {
1822 return;
1823 }
1824 ResourceMark rm;
1825 deoptimize_single_frame(thread, fr, reason);
1826 }
1827
1828 #if INCLUDE_JVMCI
1829 address Deoptimization::deoptimize_for_missing_exception_handler(nmethod* nm) {
1830 // there is no exception handler for this pc => deoptimize
1831 nm->make_not_entrant(nmethod::InvalidationReason::MISSING_EXCEPTION_HANDLER);
1832
1833 // Use Deoptimization::deoptimize for all of its side-effects:
1834 // gathering traps statistics, logging...
1835 // it also patches the return pc but we do not care about that
1836 // since we return a continuation to the deopt_blob below.
1837 JavaThread* thread = JavaThread::current();
1838 RegisterMap reg_map(thread,
1839 RegisterMap::UpdateMap::skip,
1840 RegisterMap::ProcessFrames::include,
1841 RegisterMap::WalkContinuation::skip);
1842 frame runtime_frame = thread->last_frame();
1843 frame caller_frame = runtime_frame.sender(®_map);
1844 assert(caller_frame.cb()->as_nmethod_or_null() == nm, "expect top frame compiled method");
1845 vframe* vf = vframe::new_vframe(&caller_frame, ®_map, thread);
1846 compiledVFrame* cvf = compiledVFrame::cast(vf);
1847 ScopeDesc* imm_scope = cvf->scope();
1848 MethodData* imm_mdo = get_method_data(thread, methodHandle(thread, imm_scope->method()), true);
1849 if (imm_mdo != nullptr) {
1850 // Lock to read ProfileData, and ensure lock is not broken by a safepoint
1851 MutexLocker ml(imm_mdo->extra_data_lock(), Mutex::_no_safepoint_check_flag);
1852
1853 ProfileData* pdata = imm_mdo->allocate_bci_to_data(imm_scope->bci(), nullptr);
1854 if (pdata != nullptr && pdata->is_BitData()) {
1855 BitData* bit_data = (BitData*) pdata;
1856 bit_data->set_exception_seen();
1857 }
1858 }
1859
1860 Deoptimization::deoptimize(thread, caller_frame, Deoptimization::Reason_not_compiled_exception_handler);
1861
1862 MethodData* trap_mdo = get_method_data(thread, methodHandle(thread, nm->method()), true);
1863 if (trap_mdo != nullptr) {
1864 trap_mdo->inc_trap_count(Deoptimization::Reason_not_compiled_exception_handler);
1865 }
1866
1867 return SharedRuntime::deopt_blob()->unpack_with_exception_in_tls();
1868 }
1869 #endif
1870
1871 void Deoptimization::deoptimize_frame_internal(JavaThread* thread, intptr_t* id, DeoptReason reason) {
1872 assert(thread == Thread::current() ||
1873 thread->is_handshake_safe_for(Thread::current()) ||
1874 SafepointSynchronize::is_at_safepoint(),
1875 "can only deoptimize other thread at a safepoint/handshake");
1876 // Compute frame and register map based on thread and sp.
1877 RegisterMap reg_map(thread,
1878 RegisterMap::UpdateMap::skip,
1879 RegisterMap::ProcessFrames::include,
1880 RegisterMap::WalkContinuation::skip);
1881 frame fr = thread->last_frame();
1882 while (fr.id() != id) {
1883 fr = fr.sender(®_map);
1884 }
1885 deoptimize(thread, fr, reason);
1886 }
1887
1888
1889 void Deoptimization::deoptimize_frame(JavaThread* thread, intptr_t* id, DeoptReason reason) {
1890 Thread* current = Thread::current();
1891 if (thread == current || thread->is_handshake_safe_for(current)) {
1892 Deoptimization::deoptimize_frame_internal(thread, id, reason);
1893 } else {
1894 VM_DeoptimizeFrame deopt(thread, id, reason);
1895 VMThread::execute(&deopt);
1896 }
1897 }
1898
1899 void Deoptimization::deoptimize_frame(JavaThread* thread, intptr_t* id) {
1900 deoptimize_frame(thread, id, Reason_constraint);
1901 }
1902
1903 // JVMTI PopFrame support
1904 JRT_LEAF(void, Deoptimization::popframe_preserve_args(JavaThread* thread, int bytes_to_save, void* start_address))
1905 {
1906 assert(thread == JavaThread::current(), "pre-condition");
1907 thread->popframe_preserve_args(in_ByteSize(bytes_to_save), start_address);
1908 }
1909 JRT_END
1910
1911 MethodData*
1912 Deoptimization::get_method_data(JavaThread* thread, const methodHandle& m,
1913 bool create_if_missing) {
1914 JavaThread* THREAD = thread; // For exception macros.
1915 MethodData* mdo = m()->method_data();
1916 if (mdo == nullptr && create_if_missing && !HAS_PENDING_EXCEPTION) {
1917 // Build an MDO. Ignore errors like OutOfMemory;
1918 // that simply means we won't have an MDO to update.
1919 Method::build_profiling_method_data(m, THREAD);
1920 if (HAS_PENDING_EXCEPTION) {
1921 // Only metaspace OOM is expected. No Java code executed.
1922 assert((PENDING_EXCEPTION->is_a(vmClasses::OutOfMemoryError_klass())), "we expect only an OOM error here");
1923 CLEAR_PENDING_EXCEPTION;
1924 }
1925 mdo = m()->method_data();
1926 }
1927 return mdo;
1928 }
1929
1930 #if COMPILER2_OR_JVMCI
1931 void Deoptimization::load_class_by_index(const constantPoolHandle& constant_pool, int index, TRAPS) {
1932 // In case of an unresolved klass entry, load the class.
1933 // This path is exercised from case _ldc in Parse::do_one_bytecode,
1934 // and probably nowhere else.
1935 // Even that case would benefit from simply re-interpreting the
1936 // bytecode, without paying special attention to the class index.
1937 // So this whole "class index" feature should probably be removed.
1938
1939 if (constant_pool->tag_at(index).is_unresolved_klass()) {
1940 Klass* tk = constant_pool->klass_at(index, THREAD);
1941 if (HAS_PENDING_EXCEPTION) {
1942 // Exception happened during classloading. We ignore the exception here, since it
1943 // is going to be rethrown since the current activation is going to be deoptimized and
1944 // the interpreter will re-execute the bytecode.
1945 // Do not clear probable Async Exceptions.
1946 CLEAR_PENDING_NONASYNC_EXCEPTION;
1947 // Class loading called java code which may have caused a stack
1948 // overflow. If the exception was thrown right before the return
1949 // to the runtime the stack is no longer guarded. Reguard the
1950 // stack otherwise if we return to the uncommon trap blob and the
1951 // stack bang causes a stack overflow we crash.
1952 JavaThread* jt = THREAD;
1953 bool guard_pages_enabled = jt->stack_overflow_state()->reguard_stack_if_needed();
1954 assert(guard_pages_enabled, "stack banging in uncommon trap blob may cause crash");
1955 }
1956 return;
1957 }
1958
1959 assert(!constant_pool->tag_at(index).is_symbol(),
1960 "no symbolic names here, please");
1961 }
1962
1963 #if INCLUDE_JFR
1964
1965 class DeoptReasonSerializer : public JfrSerializer {
1966 public:
1967 void serialize(JfrCheckpointWriter& writer) {
1968 writer.write_count((u4)(Deoptimization::Reason_LIMIT + 1)); // + Reason::many (-1)
1969 for (int i = -1; i < Deoptimization::Reason_LIMIT; ++i) {
1970 writer.write_key((u8)i);
1971 writer.write(Deoptimization::trap_reason_name(i));
1972 }
1973 }
1974 };
1975
1976 class DeoptActionSerializer : public JfrSerializer {
1977 public:
1978 void serialize(JfrCheckpointWriter& writer) {
1979 static const u4 nof_actions = Deoptimization::Action_LIMIT;
1980 writer.write_count(nof_actions);
1981 for (u4 i = 0; i < Deoptimization::Action_LIMIT; ++i) {
1982 writer.write_key(i);
1983 writer.write(Deoptimization::trap_action_name((int)i));
1984 }
1985 }
1986 };
1987
1988 static void register_serializers() {
1989 static int critical_section = 0;
1990 if (1 == critical_section || Atomic::cmpxchg(&critical_section, 0, 1) == 1) {
1991 return;
1992 }
1993 JfrSerializer::register_serializer(TYPE_DEOPTIMIZATIONREASON, true, new DeoptReasonSerializer());
1994 JfrSerializer::register_serializer(TYPE_DEOPTIMIZATIONACTION, true, new DeoptActionSerializer());
1995 }
1996
1997 static void post_deoptimization_event(nmethod* nm,
1998 const Method* method,
1999 int trap_bci,
2000 int instruction,
2001 Deoptimization::DeoptReason reason,
2002 Deoptimization::DeoptAction action) {
2003 assert(nm != nullptr, "invariant");
2004 assert(method != nullptr, "invariant");
2005 if (EventDeoptimization::is_enabled()) {
2006 static bool serializers_registered = false;
2007 if (!serializers_registered) {
2008 register_serializers();
2009 serializers_registered = true;
2010 }
2011 EventDeoptimization event;
2012 event.set_compileId(nm->compile_id());
2013 event.set_compiler(nm->compiler_type());
2014 event.set_method(method);
2015 event.set_lineNumber(method->line_number_from_bci(trap_bci));
2016 event.set_bci(trap_bci);
2017 event.set_instruction(instruction);
2018 event.set_reason(reason);
2019 event.set_action(action);
2020 event.commit();
2021 }
2022 }
2023
2024 #endif // INCLUDE_JFR
2025
2026 static void log_deopt(nmethod* nm, Method* tm, intptr_t pc, frame& fr, int trap_bci,
2027 const char* reason_name, const char* reason_action) {
2028 LogTarget(Debug, deoptimization) lt;
2029 if (lt.is_enabled()) {
2030 LogStream ls(lt);
2031 bool is_osr = nm->is_osr_method();
2032 ls.print("cid=%4d %s level=%d",
2033 nm->compile_id(), (is_osr ? "osr" : " "), nm->comp_level());
2034 ls.print(" %s", tm->name_and_sig_as_C_string());
2035 ls.print(" trap_bci=%d ", trap_bci);
2036 if (is_osr) {
2037 ls.print("osr_bci=%d ", nm->osr_entry_bci());
2038 }
2039 ls.print("%s ", reason_name);
2040 ls.print("%s ", reason_action);
2041 ls.print_cr("pc=" INTPTR_FORMAT " relative_pc=" INTPTR_FORMAT,
2042 pc, fr.pc() - nm->code_begin());
2043 }
2044 }
2045
2046 JRT_ENTRY(void, Deoptimization::uncommon_trap_inner(JavaThread* current, jint trap_request)) {
2047 HandleMark hm(current);
2048
2049 // uncommon_trap() is called at the beginning of the uncommon trap
2050 // handler. Note this fact before we start generating temporary frames
2051 // that can confuse an asynchronous stack walker. This counter is
2052 // decremented at the end of unpack_frames().
2053
2054 current->inc_in_deopt_handler();
2055
2056 #if INCLUDE_JVMCI
2057 // JVMCI might need to get an exception from the stack, which in turn requires the register map to be valid
2058 RegisterMap reg_map(current,
2059 RegisterMap::UpdateMap::include,
2060 RegisterMap::ProcessFrames::include,
2061 RegisterMap::WalkContinuation::skip);
2062 #else
2063 RegisterMap reg_map(current,
2064 RegisterMap::UpdateMap::skip,
2065 RegisterMap::ProcessFrames::include,
2066 RegisterMap::WalkContinuation::skip);
2067 #endif
2068 frame stub_frame = current->last_frame();
2069 frame fr = stub_frame.sender(®_map);
2070
2071 // Log a message
2072 Events::log_deopt_message(current, "Uncommon trap: trap_request=" INT32_FORMAT_X_0 " fr.pc=" INTPTR_FORMAT " relative=" INTPTR_FORMAT,
2073 trap_request, p2i(fr.pc()), fr.pc() - fr.cb()->code_begin());
2074
2075 {
2076 ResourceMark rm;
2077
2078 DeoptReason reason = trap_request_reason(trap_request);
2079 DeoptAction action = trap_request_action(trap_request);
2080 #if INCLUDE_JVMCI
2081 int debug_id = trap_request_debug_id(trap_request);
2082 #endif
2083 jint unloaded_class_index = trap_request_index(trap_request); // CP idx or -1
2084
2085 vframe* vf = vframe::new_vframe(&fr, ®_map, current);
2086 compiledVFrame* cvf = compiledVFrame::cast(vf);
2087
2088 nmethod* nm = cvf->code();
2089
2090 ScopeDesc* trap_scope = cvf->scope();
2091
2092 bool is_receiver_constraint_failure = COMPILER2_PRESENT(VerifyReceiverTypes &&) (reason == Deoptimization::Reason_receiver_constraint);
2093
2094 if (is_receiver_constraint_failure) {
2095 tty->print_cr(" bci=%d pc=" INTPTR_FORMAT ", relative_pc=" INTPTR_FORMAT ", method=%s" JVMCI_ONLY(", debug_id=%d"),
2096 trap_scope->bci(), p2i(fr.pc()), fr.pc() - nm->code_begin(), trap_scope->method()->name_and_sig_as_C_string()
2097 JVMCI_ONLY(COMMA debug_id));
2098 }
2099
2100 methodHandle trap_method(current, trap_scope->method());
2101 int trap_bci = trap_scope->bci();
2102 #if INCLUDE_JVMCI
2103 jlong speculation = current->pending_failed_speculation();
2104 if (nm->is_compiled_by_jvmci()) {
2105 nm->update_speculation(current);
2106 } else {
2107 assert(speculation == 0, "There should not be a speculation for methods compiled by non-JVMCI compilers");
2108 }
2109
2110 if (trap_bci == SynchronizationEntryBCI) {
2111 trap_bci = 0;
2112 current->set_pending_monitorenter(true);
2113 }
2114
2115 if (reason == Deoptimization::Reason_transfer_to_interpreter) {
2116 current->set_pending_transfer_to_interpreter(true);
2117 }
2118 #endif
2119
2120 Bytecodes::Code trap_bc = trap_method->java_code_at(trap_bci);
2121 // Record this event in the histogram.
2122 gather_statistics(reason, action, trap_bc);
2123
2124 // Ensure that we can record deopt. history:
2125 bool create_if_missing = ProfileTraps;
2126
2127 methodHandle profiled_method;
2128 #if INCLUDE_JVMCI
2129 if (nm->is_compiled_by_jvmci()) {
2130 profiled_method = methodHandle(current, nm->method());
2131 } else {
2132 profiled_method = trap_method;
2133 }
2134 #else
2135 profiled_method = trap_method;
2136 #endif
2137
2138 MethodData* trap_mdo =
2139 get_method_data(current, profiled_method, create_if_missing);
2140
2141 { // Log Deoptimization event for JFR, UL and event system
2142 Method* tm = trap_method();
2143 const char* reason_name = trap_reason_name(reason);
2144 const char* reason_action = trap_action_name(action);
2145 intptr_t pc = p2i(fr.pc());
2146
2147 JFR_ONLY(post_deoptimization_event(nm, tm, trap_bci, trap_bc, reason, action);)
2148 log_deopt(nm, tm, pc, fr, trap_bci, reason_name, reason_action);
2149 Events::log_deopt_message(current, "Uncommon trap: reason=%s action=%s pc=" INTPTR_FORMAT " method=%s @ %d %s",
2150 reason_name, reason_action, pc,
2151 tm->name_and_sig_as_C_string(), trap_bci, nm->compiler_name());
2152 }
2153
2154 // Print a bunch of diagnostics, if requested.
2155 if (TraceDeoptimization || LogCompilation || is_receiver_constraint_failure) {
2156 ResourceMark rm;
2157
2158 // Lock to read ProfileData, and ensure lock is not broken by a safepoint
2159 // We must do this already now, since we cannot acquire this lock while
2160 // holding the tty lock (lock ordering by rank).
2161 MutexLocker ml(trap_mdo->extra_data_lock(), Mutex::_no_safepoint_check_flag);
2162
2163 ttyLocker ttyl;
2164
2165 char buf[100];
2166 if (xtty != nullptr) {
2167 xtty->begin_head("uncommon_trap thread='%zu' %s",
2168 os::current_thread_id(),
2169 format_trap_request(buf, sizeof(buf), trap_request));
2170 #if INCLUDE_JVMCI
2171 if (speculation != 0) {
2172 xtty->print(" speculation='" JLONG_FORMAT "'", speculation);
2173 }
2174 #endif
2175 nm->log_identity(xtty);
2176 }
2177 Symbol* class_name = nullptr;
2178 bool unresolved = false;
2179 if (unloaded_class_index >= 0) {
2180 constantPoolHandle constants (current, trap_method->constants());
2181 if (constants->tag_at(unloaded_class_index).is_unresolved_klass()) {
2182 class_name = constants->klass_name_at(unloaded_class_index);
2183 unresolved = true;
2184 if (xtty != nullptr)
2185 xtty->print(" unresolved='1'");
2186 } else if (constants->tag_at(unloaded_class_index).is_symbol()) {
2187 class_name = constants->symbol_at(unloaded_class_index);
2188 }
2189 if (xtty != nullptr)
2190 xtty->name(class_name);
2191 }
2192 if (xtty != nullptr && trap_mdo != nullptr && (int)reason < (int)MethodData::_trap_hist_limit) {
2193 // Dump the relevant MDO state.
2194 // This is the deopt count for the current reason, any previous
2195 // reasons or recompiles seen at this point.
2196 int dcnt = trap_mdo->trap_count(reason);
2197 if (dcnt != 0)
2198 xtty->print(" count='%d'", dcnt);
2199
2200 // We need to lock to read the ProfileData. But to keep the locks ordered, we need to
2201 // lock extra_data_lock before the tty lock.
2202 ProfileData* pdata = trap_mdo->bci_to_data(trap_bci);
2203 int dos = (pdata == nullptr)? 0: pdata->trap_state();
2204 if (dos != 0) {
2205 xtty->print(" state='%s'", format_trap_state(buf, sizeof(buf), dos));
2206 if (trap_state_is_recompiled(dos)) {
2207 int recnt2 = trap_mdo->overflow_recompile_count();
2208 if (recnt2 != 0)
2209 xtty->print(" recompiles2='%d'", recnt2);
2210 }
2211 }
2212 }
2213 if (xtty != nullptr) {
2214 xtty->stamp();
2215 xtty->end_head();
2216 }
2217 if (TraceDeoptimization) { // make noise on the tty
2218 stringStream st;
2219 st.print("UNCOMMON TRAP method=%s", trap_scope->method()->name_and_sig_as_C_string());
2220 st.print(" bci=%d pc=" INTPTR_FORMAT ", relative_pc=" INTPTR_FORMAT JVMCI_ONLY(", debug_id=%d"),
2221 trap_scope->bci(), p2i(fr.pc()), fr.pc() - nm->code_begin() JVMCI_ONLY(COMMA debug_id));
2222 st.print(" compiler=%s compile_id=%d", nm->compiler_name(), nm->compile_id());
2223 #if INCLUDE_JVMCI
2224 if (nm->is_compiled_by_jvmci()) {
2225 const char* installed_code_name = nm->jvmci_name();
2226 if (installed_code_name != nullptr) {
2227 st.print(" (JVMCI: installed code name=%s) ", installed_code_name);
2228 }
2229 }
2230 #endif
2231 st.print(" (@" INTPTR_FORMAT ") thread=%zu reason=%s action=%s unloaded_class_index=%d" JVMCI_ONLY(" debug_id=%d"),
2232 p2i(fr.pc()),
2233 os::current_thread_id(),
2234 trap_reason_name(reason),
2235 trap_action_name(action),
2236 unloaded_class_index
2237 #if INCLUDE_JVMCI
2238 , debug_id
2239 #endif
2240 );
2241 if (class_name != nullptr) {
2242 st.print(unresolved ? " unresolved class: " : " symbol: ");
2243 class_name->print_symbol_on(&st);
2244 }
2245 st.cr();
2246 tty->print_raw(st.freeze());
2247 }
2248 if (xtty != nullptr) {
2249 // Log the precise location of the trap.
2250 for (ScopeDesc* sd = trap_scope; ; sd = sd->sender()) {
2251 xtty->begin_elem("jvms bci='%d'", sd->bci());
2252 xtty->method(sd->method());
2253 xtty->end_elem();
2254 if (sd->is_top()) break;
2255 }
2256 xtty->tail("uncommon_trap");
2257 }
2258 }
2259 // (End diagnostic printout.)
2260
2261 if (is_receiver_constraint_failure) {
2262 fatal("missing receiver type check");
2263 }
2264
2265 // Load class if necessary
2266 if (unloaded_class_index >= 0) {
2267 constantPoolHandle constants(current, trap_method->constants());
2268 load_class_by_index(constants, unloaded_class_index, THREAD);
2269 }
2270
2271 // Flush the nmethod if necessary and desirable.
2272 //
2273 // We need to avoid situations where we are re-flushing the nmethod
2274 // because of a hot deoptimization site. Repeated flushes at the same
2275 // point need to be detected by the compiler and avoided. If the compiler
2276 // cannot avoid them (or has a bug and "refuses" to avoid them), this
2277 // module must take measures to avoid an infinite cycle of recompilation
2278 // and deoptimization. There are several such measures:
2279 //
2280 // 1. If a recompilation is ordered a second time at some site X
2281 // and for the same reason R, the action is adjusted to 'reinterpret',
2282 // to give the interpreter time to exercise the method more thoroughly.
2283 // If this happens, the method's overflow_recompile_count is incremented.
2284 //
2285 // 2. If the compiler fails to reduce the deoptimization rate, then
2286 // the method's overflow_recompile_count will begin to exceed the set
2287 // limit PerBytecodeRecompilationCutoff. If this happens, the action
2288 // is adjusted to 'make_not_compilable', and the method is abandoned
2289 // to the interpreter. This is a performance hit for hot methods,
2290 // but is better than a disastrous infinite cycle of recompilations.
2291 // (Actually, only the method containing the site X is abandoned.)
2292 //
2293 // 3. In parallel with the previous measures, if the total number of
2294 // recompilations of a method exceeds the much larger set limit
2295 // PerMethodRecompilationCutoff, the method is abandoned.
2296 // This should only happen if the method is very large and has
2297 // many "lukewarm" deoptimizations. The code which enforces this
2298 // limit is elsewhere (class nmethod, class Method).
2299 //
2300 // Note that the per-BCI 'is_recompiled' bit gives the compiler one chance
2301 // to recompile at each bytecode independently of the per-BCI cutoff.
2302 //
2303 // The decision to update code is up to the compiler, and is encoded
2304 // in the Action_xxx code. If the compiler requests Action_none
2305 // no trap state is changed, no compiled code is changed, and the
2306 // computation suffers along in the interpreter.
2307 //
2308 // The other action codes specify various tactics for decompilation
2309 // and recompilation. Action_maybe_recompile is the loosest, and
2310 // allows the compiled code to stay around until enough traps are seen,
2311 // and until the compiler gets around to recompiling the trapping method.
2312 //
2313 // The other actions cause immediate removal of the present code.
2314
2315 // Traps caused by injected profile shouldn't pollute trap counts.
2316 bool injected_profile_trap = trap_method->has_injected_profile() &&
2317 (reason == Reason_intrinsic || reason == Reason_unreached);
2318
2319 bool update_trap_state = (reason != Reason_tenured) && !injected_profile_trap;
2320 bool make_not_entrant = false;
2321 bool make_not_compilable = false;
2322 bool reprofile = false;
2323 switch (action) {
2324 case Action_none:
2325 // Keep the old code.
2326 update_trap_state = false;
2327 break;
2328 case Action_maybe_recompile:
2329 // Do not need to invalidate the present code, but we can
2330 // initiate another
2331 // Start compiler without (necessarily) invalidating the nmethod.
2332 // The system will tolerate the old code, but new code should be
2333 // generated when possible.
2334 break;
2335 case Action_reinterpret:
2336 // Go back into the interpreter for a while, and then consider
2337 // recompiling form scratch.
2338 make_not_entrant = true;
2339 // Reset invocation counter for outer most method.
2340 // This will allow the interpreter to exercise the bytecodes
2341 // for a while before recompiling.
2342 // By contrast, Action_make_not_entrant is immediate.
2343 //
2344 // Note that the compiler will track null_check, null_assert,
2345 // range_check, and class_check events and log them as if they
2346 // had been traps taken from compiled code. This will update
2347 // the MDO trap history so that the next compilation will
2348 // properly detect hot trap sites.
2349 reprofile = true;
2350 break;
2351 case Action_make_not_entrant:
2352 // Request immediate recompilation, and get rid of the old code.
2353 // Make them not entrant, so next time they are called they get
2354 // recompiled. Unloaded classes are loaded now so recompile before next
2355 // time they are called. Same for uninitialized. The interpreter will
2356 // link the missing class, if any.
2357 make_not_entrant = true;
2358 break;
2359 case Action_make_not_compilable:
2360 // Give up on compiling this method at all.
2361 make_not_entrant = true;
2362 make_not_compilable = true;
2363 break;
2364 default:
2365 ShouldNotReachHere();
2366 }
2367
2368 #if INCLUDE_JVMCI
2369 // Deoptimization count is used by the CompileBroker to reason about compilations
2370 // it requests so do not pollute the count for deoptimizations in non-default (i.e.
2371 // non-CompilerBroker) compilations.
2372 if (nm->jvmci_skip_profile_deopt()) {
2373 update_trap_state = false;
2374 }
2375 #endif
2376 // Setting +ProfileTraps fixes the following, on all platforms:
2377 // The result is infinite heroic-opt-uncommon-trap/deopt/recompile cycles, since the
2378 // recompile relies on a MethodData* to record heroic opt failures.
2379
2380 // Whether the interpreter is producing MDO data or not, we also need
2381 // to use the MDO to detect hot deoptimization points and control
2382 // aggressive optimization.
2383 bool inc_recompile_count = false;
2384
2385 // Lock to read ProfileData, and ensure lock is not broken by a safepoint
2386 ConditionalMutexLocker ml((trap_mdo != nullptr) ? trap_mdo->extra_data_lock() : nullptr,
2387 (trap_mdo != nullptr),
2388 Mutex::_no_safepoint_check_flag);
2389 ProfileData* pdata = nullptr;
2390 if (ProfileTraps && CompilerConfig::is_c2_or_jvmci_compiler_enabled() && update_trap_state && trap_mdo != nullptr) {
2391 assert(trap_mdo == get_method_data(current, profiled_method, false), "sanity");
2392 uint this_trap_count = 0;
2393 bool maybe_prior_trap = false;
2394 bool maybe_prior_recompile = false;
2395
2396 pdata = query_update_method_data(trap_mdo, trap_bci, reason, true,
2397 #if INCLUDE_JVMCI
2398 nm->is_compiled_by_jvmci() && nm->is_osr_method(),
2399 #endif
2400 nm->method(),
2401 //outputs:
2402 this_trap_count,
2403 maybe_prior_trap,
2404 maybe_prior_recompile);
2405 // Because the interpreter also counts null, div0, range, and class
2406 // checks, these traps from compiled code are double-counted.
2407 // This is harmless; it just means that the PerXTrapLimit values
2408 // are in effect a little smaller than they look.
2409
2410 DeoptReason per_bc_reason = reason_recorded_per_bytecode_if_any(reason);
2411 if (per_bc_reason != Reason_none) {
2412 // Now take action based on the partially known per-BCI history.
2413 if (maybe_prior_trap
2414 && this_trap_count >= (uint)PerBytecodeTrapLimit) {
2415 // If there are too many traps at this BCI, force a recompile.
2416 // This will allow the compiler to see the limit overflow, and
2417 // take corrective action, if possible. The compiler generally
2418 // does not use the exact PerBytecodeTrapLimit value, but instead
2419 // changes its tactics if it sees any traps at all. This provides
2420 // a little hysteresis, delaying a recompile until a trap happens
2421 // several times.
2422 //
2423 // Actually, since there is only one bit of counter per BCI,
2424 // the possible per-BCI counts are {0,1,(per-method count)}.
2425 // This produces accurate results if in fact there is only
2426 // one hot trap site, but begins to get fuzzy if there are
2427 // many sites. For example, if there are ten sites each
2428 // trapping two or more times, they each get the blame for
2429 // all of their traps.
2430 make_not_entrant = true;
2431 }
2432
2433 // Detect repeated recompilation at the same BCI, and enforce a limit.
2434 if (make_not_entrant && maybe_prior_recompile) {
2435 // More than one recompile at this point.
2436 inc_recompile_count = maybe_prior_trap;
2437 }
2438 } else {
2439 // For reasons which are not recorded per-bytecode, we simply
2440 // force recompiles unconditionally.
2441 // (Note that PerMethodRecompilationCutoff is enforced elsewhere.)
2442 make_not_entrant = true;
2443 }
2444
2445 // Go back to the compiler if there are too many traps in this method.
2446 if (this_trap_count >= per_method_trap_limit(reason)) {
2447 // If there are too many traps in this method, force a recompile.
2448 // This will allow the compiler to see the limit overflow, and
2449 // take corrective action, if possible.
2450 // (This condition is an unlikely backstop only, because the
2451 // PerBytecodeTrapLimit is more likely to take effect first,
2452 // if it is applicable.)
2453 make_not_entrant = true;
2454 }
2455
2456 // Here's more hysteresis: If there has been a recompile at
2457 // this trap point already, run the method in the interpreter
2458 // for a while to exercise it more thoroughly.
2459 if (make_not_entrant && maybe_prior_recompile && maybe_prior_trap) {
2460 reprofile = true;
2461 }
2462 }
2463
2464 // Take requested actions on the method:
2465
2466 // Recompile
2467 if (make_not_entrant) {
2468 if (!nm->make_not_entrant(nmethod::InvalidationReason::UNCOMMON_TRAP)) {
2469 return; // the call did not change nmethod's state
2470 }
2471
2472 if (pdata != nullptr) {
2473 // Record the recompilation event, if any.
2474 int tstate0 = pdata->trap_state();
2475 int tstate1 = trap_state_set_recompiled(tstate0, true);
2476 if (tstate1 != tstate0)
2477 pdata->set_trap_state(tstate1);
2478 }
2479
2480 // For code aging we count traps separately here, using make_not_entrant()
2481 // as a guard against simultaneous deopts in multiple threads.
2482 if (reason == Reason_tenured && trap_mdo != nullptr) {
2483 trap_mdo->inc_tenure_traps();
2484 }
2485 }
2486 if (inc_recompile_count) {
2487 trap_mdo->inc_overflow_recompile_count();
2488 if ((uint)trap_mdo->overflow_recompile_count() >
2489 (uint)PerBytecodeRecompilationCutoff) {
2490 // Give up on the method containing the bad BCI.
2491 if (trap_method() == nm->method()) {
2492 make_not_compilable = true;
2493 } else {
2494 trap_method->set_not_compilable("overflow_recompile_count > PerBytecodeRecompilationCutoff", CompLevel_full_optimization);
2495 // But give grace to the enclosing nm->method().
2496 }
2497 }
2498 }
2499
2500 // Reprofile
2501 if (reprofile) {
2502 CompilationPolicy::reprofile(trap_scope, nm->is_osr_method());
2503 }
2504
2505 // Give up compiling
2506 if (make_not_compilable && !nm->method()->is_not_compilable(CompLevel_full_optimization)) {
2507 assert(make_not_entrant, "consistent");
2508 nm->method()->set_not_compilable("give up compiling", CompLevel_full_optimization);
2509 }
2510
2511 if (ProfileExceptionHandlers && trap_mdo != nullptr) {
2512 BitData* exception_handler_data = trap_mdo->exception_handler_bci_to_data_or_null(trap_bci);
2513 if (exception_handler_data != nullptr) {
2514 // uncommon trap at the start of an exception handler.
2515 // C2 generates these for un-entered exception handlers.
2516 // mark the handler as entered to avoid generating
2517 // another uncommon trap the next time the handler is compiled
2518 exception_handler_data->set_exception_handler_entered();
2519 }
2520 }
2521
2522 } // Free marked resources
2523
2524 }
2525 JRT_END
2526
2527 ProfileData*
2528 Deoptimization::query_update_method_data(MethodData* trap_mdo,
2529 int trap_bci,
2530 Deoptimization::DeoptReason reason,
2531 bool update_total_trap_count,
2532 #if INCLUDE_JVMCI
2533 bool is_osr,
2534 #endif
2535 Method* compiled_method,
2536 //outputs:
2537 uint& ret_this_trap_count,
2538 bool& ret_maybe_prior_trap,
2539 bool& ret_maybe_prior_recompile) {
2540 trap_mdo->check_extra_data_locked();
2541
2542 bool maybe_prior_trap = false;
2543 bool maybe_prior_recompile = false;
2544 uint this_trap_count = 0;
2545 if (update_total_trap_count) {
2546 uint idx = reason;
2547 #if INCLUDE_JVMCI
2548 if (is_osr) {
2549 // Upper half of history array used for traps in OSR compilations
2550 idx += Reason_TRAP_HISTORY_LENGTH;
2551 }
2552 #endif
2553 uint prior_trap_count = trap_mdo->trap_count(idx);
2554 this_trap_count = trap_mdo->inc_trap_count(idx);
2555
2556 // If the runtime cannot find a place to store trap history,
2557 // it is estimated based on the general condition of the method.
2558 // If the method has ever been recompiled, or has ever incurred
2559 // a trap with the present reason , then this BCI is assumed
2560 // (pessimistically) to be the culprit.
2561 maybe_prior_trap = (prior_trap_count != 0);
2562 maybe_prior_recompile = (trap_mdo->decompile_count() != 0);
2563 }
2564 ProfileData* pdata = nullptr;
2565
2566
2567 // For reasons which are recorded per bytecode, we check per-BCI data.
2568 DeoptReason per_bc_reason = reason_recorded_per_bytecode_if_any(reason);
2569 assert(per_bc_reason != Reason_none || update_total_trap_count, "must be");
2570 if (per_bc_reason != Reason_none) {
2571 // Find the profile data for this BCI. If there isn't one,
2572 // try to allocate one from the MDO's set of spares.
2573 // This will let us detect a repeated trap at this point.
2574 pdata = trap_mdo->allocate_bci_to_data(trap_bci, reason_is_speculate(reason) ? compiled_method : nullptr);
2575
2576 if (pdata != nullptr) {
2577 if (reason_is_speculate(reason) && !pdata->is_SpeculativeTrapData()) {
2578 if (LogCompilation && xtty != nullptr) {
2579 ttyLocker ttyl;
2580 // no more room for speculative traps in this MDO
2581 xtty->elem("speculative_traps_oom");
2582 }
2583 }
2584 // Query the trap state of this profile datum.
2585 int tstate0 = pdata->trap_state();
2586 if (!trap_state_has_reason(tstate0, per_bc_reason))
2587 maybe_prior_trap = false;
2588 if (!trap_state_is_recompiled(tstate0))
2589 maybe_prior_recompile = false;
2590
2591 // Update the trap state of this profile datum.
2592 int tstate1 = tstate0;
2593 // Record the reason.
2594 tstate1 = trap_state_add_reason(tstate1, per_bc_reason);
2595 // Store the updated state on the MDO, for next time.
2596 if (tstate1 != tstate0)
2597 pdata->set_trap_state(tstate1);
2598 } else {
2599 if (LogCompilation && xtty != nullptr) {
2600 ttyLocker ttyl;
2601 // Missing MDP? Leave a small complaint in the log.
2602 xtty->elem("missing_mdp bci='%d'", trap_bci);
2603 }
2604 }
2605 }
2606
2607 // Return results:
2608 ret_this_trap_count = this_trap_count;
2609 ret_maybe_prior_trap = maybe_prior_trap;
2610 ret_maybe_prior_recompile = maybe_prior_recompile;
2611 return pdata;
2612 }
2613
2614 void
2615 Deoptimization::update_method_data_from_interpreter(MethodData* trap_mdo, int trap_bci, int reason) {
2616 ResourceMark rm;
2617 // Ignored outputs:
2618 uint ignore_this_trap_count;
2619 bool ignore_maybe_prior_trap;
2620 bool ignore_maybe_prior_recompile;
2621 assert(!reason_is_speculate(reason), "reason speculate only used by compiler");
2622 // JVMCI uses the total counts to determine if deoptimizations are happening too frequently -> do not adjust total counts
2623 bool update_total_counts = true JVMCI_ONLY( && !UseJVMCICompiler);
2624
2625 // Lock to read ProfileData, and ensure lock is not broken by a safepoint
2626 MutexLocker ml(trap_mdo->extra_data_lock(), Mutex::_no_safepoint_check_flag);
2627
2628 query_update_method_data(trap_mdo, trap_bci,
2629 (DeoptReason)reason,
2630 update_total_counts,
2631 #if INCLUDE_JVMCI
2632 false,
2633 #endif
2634 nullptr,
2635 ignore_this_trap_count,
2636 ignore_maybe_prior_trap,
2637 ignore_maybe_prior_recompile);
2638 }
2639
2640 Deoptimization::UnrollBlock* Deoptimization::uncommon_trap(JavaThread* current, jint trap_request, jint exec_mode) {
2641 // Enable WXWrite: current function is called from methods compiled by C2 directly
2642 MACOS_AARCH64_ONLY(ThreadWXEnable wx(WXWrite, current));
2643
2644 // Still in Java no safepoints
2645 {
2646 // This enters VM and may safepoint
2647 uncommon_trap_inner(current, trap_request);
2648 }
2649 HandleMark hm(current);
2650 return fetch_unroll_info_helper(current, exec_mode);
2651 }
2652
2653 // Local derived constants.
2654 // Further breakdown of DataLayout::trap_state, as promised by DataLayout.
2655 const int DS_REASON_MASK = ((uint)DataLayout::trap_mask) >> 1;
2656 const int DS_RECOMPILE_BIT = DataLayout::trap_mask - DS_REASON_MASK;
2657
2658 //---------------------------trap_state_reason---------------------------------
2659 Deoptimization::DeoptReason
2660 Deoptimization::trap_state_reason(int trap_state) {
2661 // This assert provides the link between the width of DataLayout::trap_bits
2662 // and the encoding of "recorded" reasons. It ensures there are enough
2663 // bits to store all needed reasons in the per-BCI MDO profile.
2664 assert(DS_REASON_MASK >= Reason_RECORDED_LIMIT, "enough bits");
2665 int recompile_bit = (trap_state & DS_RECOMPILE_BIT);
2666 trap_state -= recompile_bit;
2667 if (trap_state == DS_REASON_MASK) {
2668 return Reason_many;
2669 } else {
2670 assert((int)Reason_none == 0, "state=0 => Reason_none");
2671 return (DeoptReason)trap_state;
2672 }
2673 }
2674 //-------------------------trap_state_has_reason-------------------------------
2675 int Deoptimization::trap_state_has_reason(int trap_state, int reason) {
2676 assert(reason_is_recorded_per_bytecode((DeoptReason)reason), "valid reason");
2677 assert(DS_REASON_MASK >= Reason_RECORDED_LIMIT, "enough bits");
2678 int recompile_bit = (trap_state & DS_RECOMPILE_BIT);
2679 trap_state -= recompile_bit;
2680 if (trap_state == DS_REASON_MASK) {
2681 return -1; // true, unspecifically (bottom of state lattice)
2682 } else if (trap_state == reason) {
2683 return 1; // true, definitely
2684 } else if (trap_state == 0) {
2685 return 0; // false, definitely (top of state lattice)
2686 } else {
2687 return 0; // false, definitely
2688 }
2689 }
2690 //-------------------------trap_state_add_reason-------------------------------
2691 int Deoptimization::trap_state_add_reason(int trap_state, int reason) {
2692 assert(reason_is_recorded_per_bytecode((DeoptReason)reason) || reason == Reason_many, "valid reason");
2693 int recompile_bit = (trap_state & DS_RECOMPILE_BIT);
2694 trap_state -= recompile_bit;
2695 if (trap_state == DS_REASON_MASK) {
2696 return trap_state + recompile_bit; // already at state lattice bottom
2697 } else if (trap_state == reason) {
2698 return trap_state + recompile_bit; // the condition is already true
2699 } else if (trap_state == 0) {
2700 return reason + recompile_bit; // no condition has yet been true
2701 } else {
2702 return DS_REASON_MASK + recompile_bit; // fall to state lattice bottom
2703 }
2704 }
2705 //-----------------------trap_state_is_recompiled------------------------------
2706 bool Deoptimization::trap_state_is_recompiled(int trap_state) {
2707 return (trap_state & DS_RECOMPILE_BIT) != 0;
2708 }
2709 //-----------------------trap_state_set_recompiled-----------------------------
2710 int Deoptimization::trap_state_set_recompiled(int trap_state, bool z) {
2711 if (z) return trap_state | DS_RECOMPILE_BIT;
2712 else return trap_state & ~DS_RECOMPILE_BIT;
2713 }
2714 //---------------------------format_trap_state---------------------------------
2715 // This is used for debugging and diagnostics, including LogFile output.
2716 const char* Deoptimization::format_trap_state(char* buf, size_t buflen,
2717 int trap_state) {
2718 assert(buflen > 0, "sanity");
2719 DeoptReason reason = trap_state_reason(trap_state);
2720 bool recomp_flag = trap_state_is_recompiled(trap_state);
2721 // Re-encode the state from its decoded components.
2722 int decoded_state = 0;
2723 if (reason_is_recorded_per_bytecode(reason) || reason == Reason_many)
2724 decoded_state = trap_state_add_reason(decoded_state, reason);
2725 if (recomp_flag)
2726 decoded_state = trap_state_set_recompiled(decoded_state, recomp_flag);
2727 // If the state re-encodes properly, format it symbolically.
2728 // Because this routine is used for debugging and diagnostics,
2729 // be robust even if the state is a strange value.
2730 size_t len;
2731 if (decoded_state != trap_state) {
2732 // Random buggy state that doesn't decode??
2733 len = jio_snprintf(buf, buflen, "#%d", trap_state);
2734 } else {
2735 len = jio_snprintf(buf, buflen, "%s%s",
2736 trap_reason_name(reason),
2737 recomp_flag ? " recompiled" : "");
2738 }
2739 return buf;
2740 }
2741
2742
2743 //--------------------------------statics--------------------------------------
2744 const char* Deoptimization::_trap_reason_name[] = {
2745 // Note: Keep this in sync. with enum DeoptReason.
2746 "none",
2747 "null_check",
2748 "null_assert" JVMCI_ONLY("_or_unreached0"),
2749 "range_check",
2750 "class_check",
2751 "array_check",
2752 "intrinsic" JVMCI_ONLY("_or_type_checked_inlining"),
2753 "bimorphic" JVMCI_ONLY("_or_optimized_type_check"),
2754 "profile_predicate",
2755 "auto_vectorization_check",
2756 "unloaded",
2757 "uninitialized",
2758 "initialized",
2759 "unreached",
2760 "unhandled",
2761 "constraint",
2762 "div0_check",
2763 "age",
2764 "predicate",
2765 "loop_limit_check",
2766 "speculate_class_check",
2767 "speculate_null_check",
2768 "speculate_null_assert",
2769 "unstable_if",
2770 "unstable_fused_if",
2771 "receiver_constraint",
2772 "short_running_loop" JVMCI_ONLY("_or_aliasing"),
2773 #if INCLUDE_JVMCI
2774 "transfer_to_interpreter",
2775 "not_compiled_exception_handler",
2776 "unresolved",
2777 "jsr_mismatch",
2778 #endif
2779 "tenured"
2780 };
2781 const char* Deoptimization::_trap_action_name[] = {
2782 // Note: Keep this in sync. with enum DeoptAction.
2783 "none",
2784 "maybe_recompile",
2785 "reinterpret",
2786 "make_not_entrant",
2787 "make_not_compilable"
2788 };
2789
2790 const char* Deoptimization::trap_reason_name(int reason) {
2791 // Check that every reason has a name
2792 STATIC_ASSERT(sizeof(_trap_reason_name)/sizeof(const char*) == Reason_LIMIT);
2793
2794 if (reason == Reason_many) return "many";
2795 if ((uint)reason < Reason_LIMIT)
2796 return _trap_reason_name[reason];
2797 static char buf[20];
2798 os::snprintf_checked(buf, sizeof(buf), "reason%d", reason);
2799 return buf;
2800 }
2801 const char* Deoptimization::trap_action_name(int action) {
2802 // Check that every action has a name
2803 STATIC_ASSERT(sizeof(_trap_action_name)/sizeof(const char*) == Action_LIMIT);
2804
2805 if ((uint)action < Action_LIMIT)
2806 return _trap_action_name[action];
2807 static char buf[20];
2808 os::snprintf_checked(buf, sizeof(buf), "action%d", action);
2809 return buf;
2810 }
2811
2812 // This is used for debugging and diagnostics, including LogFile output.
2813 const char* Deoptimization::format_trap_request(char* buf, size_t buflen,
2814 int trap_request) {
2815 jint unloaded_class_index = trap_request_index(trap_request);
2816 const char* reason = trap_reason_name(trap_request_reason(trap_request));
2817 const char* action = trap_action_name(trap_request_action(trap_request));
2818 #if INCLUDE_JVMCI
2819 int debug_id = trap_request_debug_id(trap_request);
2820 #endif
2821 size_t len;
2822 if (unloaded_class_index < 0) {
2823 len = jio_snprintf(buf, buflen, "reason='%s' action='%s'" JVMCI_ONLY(" debug_id='%d'"),
2824 reason, action
2825 #if INCLUDE_JVMCI
2826 ,debug_id
2827 #endif
2828 );
2829 } else {
2830 len = jio_snprintf(buf, buflen, "reason='%s' action='%s' index='%d'" JVMCI_ONLY(" debug_id='%d'"),
2831 reason, action, unloaded_class_index
2832 #if INCLUDE_JVMCI
2833 ,debug_id
2834 #endif
2835 );
2836 }
2837 return buf;
2838 }
2839
2840 juint Deoptimization::_deoptimization_hist
2841 [Deoptimization::Reason_LIMIT]
2842 [1 + Deoptimization::Action_LIMIT]
2843 [Deoptimization::BC_CASE_LIMIT]
2844 = {0};
2845
2846 enum {
2847 LSB_BITS = 8,
2848 LSB_MASK = right_n_bits(LSB_BITS)
2849 };
2850
2851 void Deoptimization::gather_statistics(DeoptReason reason, DeoptAction action,
2852 Bytecodes::Code bc) {
2853 assert(reason >= 0 && reason < Reason_LIMIT, "oob");
2854 assert(action >= 0 && action < Action_LIMIT, "oob");
2855 _deoptimization_hist[Reason_none][0][0] += 1; // total
2856 _deoptimization_hist[reason][0][0] += 1; // per-reason total
2857 juint* cases = _deoptimization_hist[reason][1+action];
2858 juint* bc_counter_addr = nullptr;
2859 juint bc_counter = 0;
2860 // Look for an unused counter, or an exact match to this BC.
2861 if (bc != Bytecodes::_illegal) {
2862 for (int bc_case = 0; bc_case < BC_CASE_LIMIT; bc_case++) {
2863 juint* counter_addr = &cases[bc_case];
2864 juint counter = *counter_addr;
2865 if ((counter == 0 && bc_counter_addr == nullptr)
2866 || (Bytecodes::Code)(counter & LSB_MASK) == bc) {
2867 // this counter is either free or is already devoted to this BC
2868 bc_counter_addr = counter_addr;
2869 bc_counter = counter | bc;
2870 }
2871 }
2872 }
2873 if (bc_counter_addr == nullptr) {
2874 // Overflow, or no given bytecode.
2875 bc_counter_addr = &cases[BC_CASE_LIMIT-1];
2876 bc_counter = (*bc_counter_addr & ~LSB_MASK); // clear LSB
2877 }
2878 *bc_counter_addr = bc_counter + (1 << LSB_BITS);
2879 }
2880
2881 jint Deoptimization::total_deoptimization_count() {
2882 return _deoptimization_hist[Reason_none][0][0];
2883 }
2884
2885 // Get the deopt count for a specific reason and a specific action. If either
2886 // one of 'reason' or 'action' is null, the method returns the sum of all
2887 // deoptimizations with the specific 'action' or 'reason' respectively.
2888 // If both arguments are null, the method returns the total deopt count.
2889 jint Deoptimization::deoptimization_count(const char *reason_str, const char *action_str) {
2890 if (reason_str == nullptr && action_str == nullptr) {
2891 return total_deoptimization_count();
2892 }
2893 juint counter = 0;
2894 for (int reason = 0; reason < Reason_LIMIT; reason++) {
2895 if (reason_str == nullptr || !strcmp(reason_str, trap_reason_name(reason))) {
2896 for (int action = 0; action < Action_LIMIT; action++) {
2897 if (action_str == nullptr || !strcmp(action_str, trap_action_name(action))) {
2898 juint* cases = _deoptimization_hist[reason][1+action];
2899 for (int bc_case = 0; bc_case < BC_CASE_LIMIT; bc_case++) {
2900 counter += cases[bc_case] >> LSB_BITS;
2901 }
2902 }
2903 }
2904 }
2905 }
2906 return counter;
2907 }
2908
2909 void Deoptimization::print_statistics() {
2910 juint total = total_deoptimization_count();
2911 juint account = total;
2912 if (total != 0) {
2913 ttyLocker ttyl;
2914 if (xtty != nullptr) xtty->head("statistics type='deoptimization'");
2915 tty->print_cr("Deoptimization traps recorded:");
2916 #define PRINT_STAT_LINE(name, r) \
2917 tty->print_cr(" %4d (%4.1f%%) %s", (int)(r), ((r) * 100.0) / total, name);
2918 PRINT_STAT_LINE("total", total);
2919 // For each non-zero entry in the histogram, print the reason,
2920 // the action, and (if specifically known) the type of bytecode.
2921 for (int reason = 0; reason < Reason_LIMIT; reason++) {
2922 for (int action = 0; action < Action_LIMIT; action++) {
2923 juint* cases = _deoptimization_hist[reason][1+action];
2924 for (int bc_case = 0; bc_case < BC_CASE_LIMIT; bc_case++) {
2925 juint counter = cases[bc_case];
2926 if (counter != 0) {
2927 char name[1*K];
2928 Bytecodes::Code bc = (Bytecodes::Code)(counter & LSB_MASK);
2929 if (bc_case == BC_CASE_LIMIT && (int)bc == 0)
2930 bc = Bytecodes::_illegal;
2931 os::snprintf_checked(name, sizeof(name), "%s/%s/%s",
2932 trap_reason_name(reason),
2933 trap_action_name(action),
2934 Bytecodes::is_defined(bc)? Bytecodes::name(bc): "other");
2935 juint r = counter >> LSB_BITS;
2936 tty->print_cr(" %40s: " UINT32_FORMAT " (%.1f%%)", name, r, (r * 100.0) / total);
2937 account -= r;
2938 }
2939 }
2940 }
2941 }
2942 if (account != 0) {
2943 PRINT_STAT_LINE("unaccounted", account);
2944 }
2945 #undef PRINT_STAT_LINE
2946 if (xtty != nullptr) xtty->tail("statistics");
2947 }
2948 }
2949
2950 #else // COMPILER2_OR_JVMCI
2951
2952
2953 // Stubs for C1 only system.
2954 bool Deoptimization::trap_state_is_recompiled(int trap_state) {
2955 return false;
2956 }
2957
2958 const char* Deoptimization::trap_reason_name(int reason) {
2959 return "unknown";
2960 }
2961
2962 jint Deoptimization::total_deoptimization_count() {
2963 return 0;
2964 }
2965
2966 jint Deoptimization::deoptimization_count(const char *reason_str, const char *action_str) {
2967 return 0;
2968 }
2969
2970 void Deoptimization::print_statistics() {
2971 // no output
2972 }
2973
2974 void
2975 Deoptimization::update_method_data_from_interpreter(MethodData* trap_mdo, int trap_bci, int reason) {
2976 // no update
2977 }
2978
2979 int Deoptimization::trap_state_has_reason(int trap_state, int reason) {
2980 return 0;
2981 }
2982
2983 void Deoptimization::gather_statistics(DeoptReason reason, DeoptAction action,
2984 Bytecodes::Code bc) {
2985 // no update
2986 }
2987
2988 const char* Deoptimization::format_trap_state(char* buf, size_t buflen,
2989 int trap_state) {
2990 jio_snprintf(buf, buflen, "#%d", trap_state);
2991 return buf;
2992 }
2993
2994 #endif // COMPILER2_OR_JVMCI