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