1 /*
2 * Copyright (c) 1997, 2024, 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/continuation.hpp"
67 #include "runtime/continuationEntry.inline.hpp"
68 #include "runtime/deoptimization.hpp"
69 #include "runtime/escapeBarrier.hpp"
70 #include "runtime/fieldDescriptor.hpp"
71 #include "runtime/fieldDescriptor.inline.hpp"
72 #include "runtime/frame.inline.hpp"
73 #include "runtime/handles.inline.hpp"
74 #include "runtime/interfaceSupport.inline.hpp"
75 #include "runtime/javaThread.hpp"
76 #include "runtime/jniHandles.inline.hpp"
77 #include "runtime/keepStackGCProcessed.hpp"
78 #include "runtime/objectMonitor.inline.hpp"
79 #include "runtime/osThread.hpp"
80 #include "runtime/safepointVerifiers.hpp"
81 #include "runtime/sharedRuntime.hpp"
82 #include "runtime/signature.hpp"
83 #include "runtime/stackFrameStream.inline.hpp"
84 #include "runtime/stackValue.hpp"
85 #include "runtime/stackWatermarkSet.hpp"
86 #include "runtime/stubRoutines.hpp"
87 #include "runtime/synchronizer.hpp"
88 #include "runtime/threadSMR.hpp"
89 #include "runtime/threadWXSetters.inline.hpp"
90 #include "runtime/vframe.hpp"
91 #include "runtime/vframeArray.hpp"
92 #include "runtime/vframe_hp.hpp"
93 #include "runtime/vmOperations.hpp"
94 #include "utilities/checkedCast.hpp"
95 #include "utilities/events.hpp"
96 #include "utilities/growableArray.hpp"
97 #include "utilities/macros.hpp"
98 #include "utilities/preserveException.hpp"
99 #include "utilities/xmlstream.hpp"
100 #if INCLUDE_JFR
101 #include "jfr/jfrEvents.hpp"
102 #include "jfr/metadata/jfrSerializer.hpp"
103 #endif
104
105 uint64_t DeoptimizationScope::_committed_deopt_gen = 0;
106 uint64_t DeoptimizationScope::_active_deopt_gen = 1;
107 bool DeoptimizationScope::_committing_in_progress = false;
108
109 DeoptimizationScope::DeoptimizationScope() : _required_gen(0) {
110 DEBUG_ONLY(_deopted = false;)
111
112 MutexLocker ml(NMethodState_lock, Mutex::_no_safepoint_check_flag);
113 // If there is nothing to deopt _required_gen is the same as comitted.
114 _required_gen = DeoptimizationScope::_committed_deopt_gen;
115 }
116
117 DeoptimizationScope::~DeoptimizationScope() {
118 assert(_deopted, "Deopt not executed");
119 }
120
121 void DeoptimizationScope::mark(nmethod* nm, bool inc_recompile_counts) {
122 ConditionalMutexLocker ml(NMethodState_lock, !NMethodState_lock->owned_by_self(), Mutex::_no_safepoint_check_flag);
123
124 // If it's already marked but we still need it to be deopted.
125 if (nm->is_marked_for_deoptimization()) {
126 dependent(nm);
127 return;
128 }
129
130 nmethod::DeoptimizationStatus status =
131 inc_recompile_counts ? nmethod::deoptimize : nmethod::deoptimize_noupdate;
132 Atomic::store(&nm->_deoptimization_status, status);
133
134 // Make sure active is not committed
135 assert(DeoptimizationScope::_committed_deopt_gen < DeoptimizationScope::_active_deopt_gen, "Must be");
136 assert(nm->_deoptimization_generation == 0, "Is already marked");
137
138 nm->_deoptimization_generation = DeoptimizationScope::_active_deopt_gen;
139 _required_gen = DeoptimizationScope::_active_deopt_gen;
140 }
141
142 void DeoptimizationScope::dependent(nmethod* nm) {
143 ConditionalMutexLocker ml(NMethodState_lock, !NMethodState_lock->owned_by_self(), Mutex::_no_safepoint_check_flag);
144
145 // A method marked by someone else may have a _required_gen lower than what we marked with.
146 // Therefore only store it if it's higher than _required_gen.
147 if (_required_gen < nm->_deoptimization_generation) {
148 _required_gen = nm->_deoptimization_generation;
149 }
150 }
151
152 void DeoptimizationScope::deoptimize_marked() {
153 assert(!_deopted, "Already deopted");
154
155 // We are not alive yet.
156 if (!Universe::is_fully_initialized()) {
157 DEBUG_ONLY(_deopted = true;)
158 return;
159 }
160
161 // Safepoints are a special case, handled here.
162 if (SafepointSynchronize::is_at_safepoint()) {
163 DeoptimizationScope::_committed_deopt_gen = DeoptimizationScope::_active_deopt_gen;
164 DeoptimizationScope::_active_deopt_gen++;
165 Deoptimization::deoptimize_all_marked();
166 DEBUG_ONLY(_deopted = true;)
167 return;
168 }
169
170 uint64_t comitting = 0;
171 bool wait = false;
172 while (true) {
173 {
174 ConditionalMutexLocker ml(NMethodState_lock, !NMethodState_lock->owned_by_self(), Mutex::_no_safepoint_check_flag);
175
176 // First we check if we or someone else already deopted the gen we want.
177 if (DeoptimizationScope::_committed_deopt_gen >= _required_gen) {
178 DEBUG_ONLY(_deopted = true;)
179 return;
180 }
181 if (!_committing_in_progress) {
182 // The version we are about to commit.
183 comitting = DeoptimizationScope::_active_deopt_gen;
184 // Make sure new marks use a higher gen.
185 DeoptimizationScope::_active_deopt_gen++;
186 _committing_in_progress = true;
187 wait = false;
188 } else {
189 // Another thread is handshaking and committing a gen.
190 wait = true;
191 }
192 }
193 if (wait) {
194 // Wait and let the concurrent handshake be performed.
195 ThreadBlockInVM tbivm(JavaThread::current());
196 os::naked_yield();
197 } else {
198 // Performs the handshake.
199 Deoptimization::deoptimize_all_marked(); // May safepoint and an additional deopt may have occurred.
200 DEBUG_ONLY(_deopted = true;)
201 {
202 ConditionalMutexLocker ml(NMethodState_lock, !NMethodState_lock->owned_by_self(), Mutex::_no_safepoint_check_flag);
203
204 // Make sure that committed doesn't go backwards.
205 // Should only happen if we did a deopt during a safepoint above.
206 if (DeoptimizationScope::_committed_deopt_gen < comitting) {
207 DeoptimizationScope::_committed_deopt_gen = comitting;
208 }
209 _committing_in_progress = false;
210
211 assert(DeoptimizationScope::_committed_deopt_gen >= _required_gen, "Must be");
212
213 return;
214 }
215 }
216 }
217 }
218
219 Deoptimization::UnrollBlock::UnrollBlock(int size_of_deoptimized_frame,
220 int caller_adjustment,
221 int caller_actual_parameters,
222 int number_of_frames,
223 intptr_t* frame_sizes,
224 address* frame_pcs,
225 BasicType return_type,
226 int exec_mode) {
227 _size_of_deoptimized_frame = size_of_deoptimized_frame;
228 _caller_adjustment = caller_adjustment;
229 _caller_actual_parameters = caller_actual_parameters;
230 _number_of_frames = number_of_frames;
231 _frame_sizes = frame_sizes;
232 _frame_pcs = frame_pcs;
233 _register_block = NEW_C_HEAP_ARRAY(intptr_t, RegisterMap::reg_count * 2, mtCompiler);
234 _return_type = return_type;
235 _initial_info = 0;
236 // PD (x86 only)
237 _counter_temp = 0;
238 _unpack_kind = exec_mode;
239 _sender_sp_temp = 0;
240
241 _total_frame_sizes = size_of_frames();
242 assert(exec_mode >= 0 && exec_mode < Unpack_LIMIT, "Unexpected exec_mode");
243 }
244
245 Deoptimization::UnrollBlock::~UnrollBlock() {
246 FREE_C_HEAP_ARRAY(intptr_t, _frame_sizes);
247 FREE_C_HEAP_ARRAY(intptr_t, _frame_pcs);
248 FREE_C_HEAP_ARRAY(intptr_t, _register_block);
249 }
250
251 int Deoptimization::UnrollBlock::size_of_frames() const {
252 // Account first for the adjustment of the initial frame
253 intptr_t result = _caller_adjustment;
254 for (int index = 0; index < number_of_frames(); index++) {
255 result += frame_sizes()[index];
256 }
257 return checked_cast<int>(result);
258 }
259
260 void Deoptimization::UnrollBlock::print() {
261 ResourceMark rm;
262 stringStream st;
263 st.print_cr("UnrollBlock");
264 st.print_cr(" size_of_deoptimized_frame = %d", _size_of_deoptimized_frame);
265 st.print( " frame_sizes: ");
266 for (int index = 0; index < number_of_frames(); index++) {
267 st.print(INTX_FORMAT " ", frame_sizes()[index]);
268 }
269 st.cr();
270 tty->print_raw(st.freeze());
271 }
272
273 // In order to make fetch_unroll_info work properly with escape
274 // analysis, the method was changed from JRT_LEAF to JRT_BLOCK_ENTRY.
275 // The actual reallocation of previously eliminated objects occurs in realloc_objects,
276 // which is called from the method fetch_unroll_info_helper below.
277 JRT_BLOCK_ENTRY(Deoptimization::UnrollBlock*, Deoptimization::fetch_unroll_info(JavaThread* current, int exec_mode))
278 // fetch_unroll_info() is called at the beginning of the deoptimization
279 // handler. Note this fact before we start generating temporary frames
280 // that can confuse an asynchronous stack walker. This counter is
281 // decremented at the end of unpack_frames().
282 current->inc_in_deopt_handler();
283
284 if (exec_mode == Unpack_exception) {
285 // When we get here, a callee has thrown an exception into a deoptimized
286 // frame. That throw might have deferred stack watermark checking until
287 // after unwinding. So we deal with such deferred requests here.
288 StackWatermarkSet::after_unwind(current);
289 }
290
291 return fetch_unroll_info_helper(current, exec_mode);
292 JRT_END
293
294 #if COMPILER2_OR_JVMCI
295 // print information about reallocated objects
296 static void print_objects(JavaThread* deoptee_thread,
297 GrowableArray<ScopeValue*>* objects, bool realloc_failures) {
298 ResourceMark rm;
299 stringStream st; // change to logStream with logging
300 st.print_cr("REALLOC OBJECTS in thread " INTPTR_FORMAT, p2i(deoptee_thread));
301 fieldDescriptor fd;
302
303 for (int i = 0; i < objects->length(); i++) {
304 ObjectValue* sv = (ObjectValue*) objects->at(i);
305 Handle obj = sv->value();
306
307 if (obj.is_null()) {
308 st.print_cr(" nullptr");
309 continue;
310 }
311
312 Klass* k = java_lang_Class::as_Klass(sv->klass()->as_ConstantOopReadValue()->value()());
313
314 st.print(" object <" INTPTR_FORMAT "> of type ", p2i(sv->value()()));
315 k->print_value_on(&st);
316 st.print_cr(" allocated (" SIZE_FORMAT " bytes)", obj->size() * HeapWordSize);
317
318 if (Verbose && k != nullptr) {
319 k->oop_print_on(obj(), &st);
320 }
321 }
322 tty->print_raw(st.freeze());
323 }
324
325 static bool rematerialize_objects(JavaThread* thread, int exec_mode, nmethod* compiled_method,
326 frame& deoptee, RegisterMap& map, GrowableArray<compiledVFrame*>* chunk,
327 bool& deoptimized_objects) {
328 bool realloc_failures = false;
329 assert (chunk->at(0)->scope() != nullptr,"expect only compiled java frames");
330
331 JavaThread* deoptee_thread = chunk->at(0)->thread();
332 assert(exec_mode == Deoptimization::Unpack_none || (deoptee_thread == thread),
333 "a frame can only be deoptimized by the owner thread");
334
335 GrowableArray<ScopeValue*>* objects = chunk->at(0)->scope()->objects_to_rematerialize(deoptee, map);
336
337 // The flag return_oop() indicates call sites which return oop
338 // in compiled code. Such sites include java method calls,
339 // runtime calls (for example, used to allocate new objects/arrays
340 // on slow code path) and any other calls generated in compiled code.
341 // It is not guaranteed that we can get such information here only
342 // by analyzing bytecode in deoptimized frames. This is why this flag
343 // is set during method compilation (see Compile::Process_OopMap_Node()).
344 // If the previous frame was popped or if we are dispatching an exception,
345 // we don't have an oop result.
346 bool save_oop_result = chunk->at(0)->scope()->return_oop() && !thread->popframe_forcing_deopt_reexecution() && (exec_mode == Deoptimization::Unpack_deopt);
347 Handle return_value;
348 if (save_oop_result) {
349 // Reallocation may trigger GC. If deoptimization happened on return from
350 // call which returns oop we need to save it since it is not in oopmap.
351 oop result = deoptee.saved_oop_result(&map);
352 assert(oopDesc::is_oop_or_null(result), "must be oop");
353 return_value = Handle(thread, result);
354 assert(Universe::heap()->is_in_or_null(result), "must be heap pointer");
355 if (TraceDeoptimization) {
356 tty->print_cr("SAVED OOP RESULT " INTPTR_FORMAT " in thread " INTPTR_FORMAT, p2i(result), p2i(thread));
357 tty->cr();
358 }
359 }
360 if (objects != nullptr) {
361 if (exec_mode == Deoptimization::Unpack_none) {
362 assert(thread->thread_state() == _thread_in_vm, "assumption");
363 JavaThread* THREAD = thread; // For exception macros.
364 // Clear pending OOM if reallocation fails and return true indicating allocation failure
365 realloc_failures = Deoptimization::realloc_objects(thread, &deoptee, &map, objects, CHECK_AND_CLEAR_(true));
366 deoptimized_objects = true;
367 } else {
368 JavaThread* current = thread; // For JRT_BLOCK
369 JRT_BLOCK
370 realloc_failures = Deoptimization::realloc_objects(thread, &deoptee, &map, objects, THREAD);
371 JRT_END
372 }
373 bool skip_internal = (compiled_method != nullptr) && !compiled_method->is_compiled_by_jvmci();
374 Deoptimization::reassign_fields(&deoptee, &map, objects, realloc_failures, skip_internal);
375 if (TraceDeoptimization) {
376 print_objects(deoptee_thread, objects, realloc_failures);
377 }
378 }
379 if (save_oop_result) {
380 // Restore result.
381 deoptee.set_saved_oop_result(&map, return_value());
382 }
383 return realloc_failures;
384 }
385
386 static void restore_eliminated_locks(JavaThread* thread, GrowableArray<compiledVFrame*>* chunk, bool realloc_failures,
387 frame& deoptee, int exec_mode, bool& deoptimized_objects) {
388 JavaThread* deoptee_thread = chunk->at(0)->thread();
389 assert(!EscapeBarrier::objs_are_deoptimized(deoptee_thread, deoptee.id()), "must relock just once");
390 assert(thread == Thread::current(), "should be");
391 HandleMark hm(thread);
392 #ifndef PRODUCT
393 bool first = true;
394 #endif // !PRODUCT
395 // Start locking from outermost/oldest frame
396 for (int i = (chunk->length() - 1); i >= 0; i--) {
397 compiledVFrame* cvf = chunk->at(i);
398 assert (cvf->scope() != nullptr,"expect only compiled java frames");
399 GrowableArray<MonitorInfo*>* monitors = cvf->monitors();
400 if (monitors->is_nonempty()) {
401 bool relocked = Deoptimization::relock_objects(thread, monitors, deoptee_thread, deoptee,
402 exec_mode, realloc_failures);
403 deoptimized_objects = deoptimized_objects || relocked;
404 #ifndef PRODUCT
405 if (PrintDeoptimizationDetails) {
406 ResourceMark rm;
407 stringStream st;
408 for (int j = 0; j < monitors->length(); j++) {
409 MonitorInfo* mi = monitors->at(j);
410 if (mi->eliminated()) {
411 if (first) {
412 first = false;
413 st.print_cr("RELOCK OBJECTS in thread " INTPTR_FORMAT, p2i(thread));
414 }
415 if (exec_mode == Deoptimization::Unpack_none) {
416 ObjectMonitor* monitor = deoptee_thread->current_waiting_monitor();
417 if (monitor != nullptr && monitor->object() == mi->owner()) {
418 st.print_cr(" object <" INTPTR_FORMAT "> DEFERRED relocking after wait", p2i(mi->owner()));
419 continue;
420 }
421 }
422 if (mi->owner_is_scalar_replaced()) {
423 Klass* k = java_lang_Class::as_Klass(mi->owner_klass());
424 st.print_cr(" failed reallocation for klass %s", k->external_name());
425 } else {
426 st.print_cr(" object <" INTPTR_FORMAT "> locked", p2i(mi->owner()));
427 }
428 }
429 }
430 tty->print_raw(st.freeze());
431 }
432 #endif // !PRODUCT
433 }
434 }
435 }
436
437 // Deoptimize objects, that is reallocate and relock them, just before they escape through JVMTI.
438 // The given vframes cover one physical frame.
439 bool Deoptimization::deoptimize_objects_internal(JavaThread* thread, GrowableArray<compiledVFrame*>* chunk,
440 bool& realloc_failures) {
441 frame deoptee = chunk->at(0)->fr();
442 JavaThread* deoptee_thread = chunk->at(0)->thread();
443 nmethod* nm = deoptee.cb()->as_nmethod_or_null();
444 RegisterMap map(chunk->at(0)->register_map());
445 bool deoptimized_objects = false;
446
447 bool const jvmci_enabled = JVMCI_ONLY(UseJVMCICompiler) NOT_JVMCI(false);
448
449 // Reallocate the non-escaping objects and restore their fields.
450 if (jvmci_enabled COMPILER2_PRESENT(|| (DoEscapeAnalysis && EliminateAllocations)
451 || EliminateAutoBox || EnableVectorAggressiveReboxing)) {
452 realloc_failures = rematerialize_objects(thread, Unpack_none, nm, deoptee, map, chunk, deoptimized_objects);
453 }
454
455 // MonitorInfo structures used in eliminate_locks are not GC safe.
456 NoSafepointVerifier no_safepoint;
457
458 // Now relock objects if synchronization on them was eliminated.
459 if (jvmci_enabled COMPILER2_PRESENT(|| ((DoEscapeAnalysis || EliminateNestedLocks) && EliminateLocks))) {
460 restore_eliminated_locks(thread, chunk, realloc_failures, deoptee, Unpack_none, deoptimized_objects);
461 }
462 return deoptimized_objects;
463 }
464 #endif // COMPILER2_OR_JVMCI
465
466 // This is factored, since it is both called from a JRT_LEAF (deoptimization) and a JRT_ENTRY (uncommon_trap)
467 Deoptimization::UnrollBlock* Deoptimization::fetch_unroll_info_helper(JavaThread* current, int exec_mode) {
468 // When we get here we are about to unwind the deoptee frame. In order to
469 // catch not yet safe to use frames, the following stack watermark barrier
470 // poll will make such frames safe to use.
471 StackWatermarkSet::before_unwind(current);
472
473 // Note: there is a safepoint safety issue here. No matter whether we enter
474 // via vanilla deopt or uncommon trap we MUST NOT stop at a safepoint once
475 // the vframeArray is created.
476 //
477
478 // Allocate our special deoptimization ResourceMark
479 DeoptResourceMark* dmark = new DeoptResourceMark(current);
480 assert(current->deopt_mark() == nullptr, "Pending deopt!");
481 current->set_deopt_mark(dmark);
482
483 frame stub_frame = current->last_frame(); // Makes stack walkable as side effect
484 RegisterMap map(current,
485 RegisterMap::UpdateMap::include,
486 RegisterMap::ProcessFrames::include,
487 RegisterMap::WalkContinuation::skip);
488 RegisterMap dummy_map(current,
489 RegisterMap::UpdateMap::skip,
490 RegisterMap::ProcessFrames::include,
491 RegisterMap::WalkContinuation::skip);
492 // Now get the deoptee with a valid map
493 frame deoptee = stub_frame.sender(&map);
494 // Set the deoptee nmethod
495 assert(current->deopt_compiled_method() == nullptr, "Pending deopt!");
496 nmethod* nm = deoptee.cb()->as_nmethod_or_null();
497 current->set_deopt_compiled_method(nm);
498
499 if (VerifyStack) {
500 current->validate_frame_layout();
501 }
502
503 // Create a growable array of VFrames where each VFrame represents an inlined
504 // Java frame. This storage is allocated with the usual system arena.
505 assert(deoptee.is_compiled_frame(), "Wrong frame type");
506 GrowableArray<compiledVFrame*>* chunk = new GrowableArray<compiledVFrame*>(10);
507 vframe* vf = vframe::new_vframe(&deoptee, &map, current);
508 while (!vf->is_top()) {
509 assert(vf->is_compiled_frame(), "Wrong frame type");
510 chunk->push(compiledVFrame::cast(vf));
511 vf = vf->sender();
512 }
513 assert(vf->is_compiled_frame(), "Wrong frame type");
514 chunk->push(compiledVFrame::cast(vf));
515
516 bool realloc_failures = false;
517
518 #if COMPILER2_OR_JVMCI
519 bool const jvmci_enabled = JVMCI_ONLY(EnableJVMCI) NOT_JVMCI(false);
520
521 // Reallocate the non-escaping objects and restore their fields. Then
522 // relock objects if synchronization on them was eliminated.
523 if (jvmci_enabled COMPILER2_PRESENT( || (DoEscapeAnalysis && EliminateAllocations)
524 || EliminateAutoBox || EnableVectorAggressiveReboxing )) {
525 bool unused;
526 realloc_failures = rematerialize_objects(current, exec_mode, nm, deoptee, map, chunk, unused);
527 }
528 #endif // COMPILER2_OR_JVMCI
529
530 // Ensure that no safepoint is taken after pointers have been stored
531 // in fields of rematerialized objects. If a safepoint occurs from here on
532 // out the java state residing in the vframeArray will be missed.
533 // Locks may be rebaised in a safepoint.
534 NoSafepointVerifier no_safepoint;
535
536 #if COMPILER2_OR_JVMCI
537 if ((jvmci_enabled COMPILER2_PRESENT( || ((DoEscapeAnalysis || EliminateNestedLocks) && EliminateLocks) ))
538 && !EscapeBarrier::objs_are_deoptimized(current, deoptee.id())) {
539 bool unused = false;
540 restore_eliminated_locks(current, chunk, realloc_failures, deoptee, exec_mode, unused);
541 }
542 #endif // COMPILER2_OR_JVMCI
543
544 ScopeDesc* trap_scope = chunk->at(0)->scope();
545 Handle exceptionObject;
546 if (trap_scope->rethrow_exception()) {
547 #ifndef PRODUCT
548 if (PrintDeoptimizationDetails) {
549 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());
550 }
551 #endif // !PRODUCT
552
553 GrowableArray<ScopeValue*>* expressions = trap_scope->expressions();
554 guarantee(expressions != nullptr && expressions->length() > 0, "must have exception to throw");
555 ScopeValue* topOfStack = expressions->top();
556 exceptionObject = StackValue::create_stack_value(&deoptee, &map, topOfStack)->get_obj();
557 guarantee(exceptionObject() != nullptr, "exception oop can not be null");
558 }
559
560 vframeArray* array = create_vframeArray(current, deoptee, &map, chunk, realloc_failures);
561 #if COMPILER2_OR_JVMCI
562 if (realloc_failures) {
563 // This destroys all ScopedValue bindings.
564 current->clear_scopedValueBindings();
565 pop_frames_failed_reallocs(current, array);
566 }
567 #endif
568
569 assert(current->vframe_array_head() == nullptr, "Pending deopt!");
570 current->set_vframe_array_head(array);
571
572 // Now that the vframeArray has been created if we have any deferred local writes
573 // added by jvmti then we can free up that structure as the data is now in the
574 // vframeArray
575
576 JvmtiDeferredUpdates::delete_updates_for_frame(current, array->original().id());
577
578 // Compute the caller frame based on the sender sp of stub_frame and stored frame sizes info.
579 CodeBlob* cb = stub_frame.cb();
580 // Verify we have the right vframeArray
581 assert(cb->frame_size() >= 0, "Unexpected frame size");
582 intptr_t* unpack_sp = stub_frame.sp() + cb->frame_size();
583
584 // If the deopt call site is a MethodHandle invoke call site we have
585 // to adjust the unpack_sp.
586 nmethod* deoptee_nm = deoptee.cb()->as_nmethod_or_null();
587 if (deoptee_nm != nullptr && deoptee_nm->is_method_handle_return(deoptee.pc()))
588 unpack_sp = deoptee.unextended_sp();
589
590 #ifdef ASSERT
591 assert(cb->is_deoptimization_stub() ||
592 cb->is_uncommon_trap_stub() ||
593 strcmp("Stub<DeoptimizationStub.deoptimizationHandler>", cb->name()) == 0 ||
594 strcmp("Stub<UncommonTrapStub.uncommonTrapHandler>", cb->name()) == 0,
595 "unexpected code blob: %s", cb->name());
596 #endif
597
598 // This is a guarantee instead of an assert because if vframe doesn't match
599 // we will unpack the wrong deoptimized frame and wind up in strange places
600 // where it will be very difficult to figure out what went wrong. Better
601 // to die an early death here than some very obscure death later when the
602 // trail is cold.
603 // Note: on ia64 this guarantee can be fooled by frames with no memory stack
604 // in that it will fail to detect a problem when there is one. This needs
605 // more work in tiger timeframe.
606 guarantee(array->unextended_sp() == unpack_sp, "vframe_array_head must contain the vframeArray to unpack");
607
608 int number_of_frames = array->frames();
609
610 // Compute the vframes' sizes. Note that frame_sizes[] entries are ordered from outermost to innermost
611 // virtual activation, which is the reverse of the elements in the vframes array.
612 intptr_t* frame_sizes = NEW_C_HEAP_ARRAY(intptr_t, number_of_frames, mtCompiler);
613 // +1 because we always have an interpreter return address for the final slot.
614 address* frame_pcs = NEW_C_HEAP_ARRAY(address, number_of_frames + 1, mtCompiler);
615 int popframe_extra_args = 0;
616 // Create an interpreter return address for the stub to use as its return
617 // address so the skeletal frames are perfectly walkable
618 frame_pcs[number_of_frames] = Interpreter::deopt_entry(vtos, 0);
619
620 // PopFrame requires that the preserved incoming arguments from the recently-popped topmost
621 // activation be put back on the expression stack of the caller for reexecution
622 if (JvmtiExport::can_pop_frame() && current->popframe_forcing_deopt_reexecution()) {
623 popframe_extra_args = in_words(current->popframe_preserved_args_size_in_words());
624 }
625
626 // Find the current pc for sender of the deoptee. Since the sender may have been deoptimized
627 // itself since the deoptee vframeArray was created we must get a fresh value of the pc rather
628 // than simply use array->sender.pc(). This requires us to walk the current set of frames
629 //
630 frame deopt_sender = stub_frame.sender(&dummy_map); // First is the deoptee frame
631 deopt_sender = deopt_sender.sender(&dummy_map); // Now deoptee caller
632
633 // It's possible that the number of parameters at the call site is
634 // different than number of arguments in the callee when method
635 // handles are used. If the caller is interpreted get the real
636 // value so that the proper amount of space can be added to it's
637 // frame.
638 bool caller_was_method_handle = false;
639 if (deopt_sender.is_interpreted_frame()) {
640 methodHandle method(current, deopt_sender.interpreter_frame_method());
641 Bytecode_invoke cur = Bytecode_invoke_check(method, deopt_sender.interpreter_frame_bci());
642 if (cur.is_invokedynamic() || cur.is_invokehandle()) {
643 // Method handle invokes may involve fairly arbitrary chains of
644 // calls so it's impossible to know how much actual space the
645 // caller has for locals.
646 caller_was_method_handle = true;
647 }
648 }
649
650 //
651 // frame_sizes/frame_pcs[0] oldest frame (int or c2i)
652 // frame_sizes/frame_pcs[1] next oldest frame (int)
653 // frame_sizes/frame_pcs[n] youngest frame (int)
654 //
655 // Now a pc in frame_pcs is actually the return address to the frame's caller (a frame
656 // owns the space for the return address to it's caller). Confusing ain't it.
657 //
658 // The vframe array can address vframes with indices running from
659 // 0.._frames-1. Index 0 is the youngest frame and _frame - 1 is the oldest (root) frame.
660 // When we create the skeletal frames we need the oldest frame to be in the zero slot
661 // in the frame_sizes/frame_pcs so the assembly code can do a trivial walk.
662 // so things look a little strange in this loop.
663 //
664 int callee_parameters = 0;
665 int callee_locals = 0;
666 for (int index = 0; index < array->frames(); index++ ) {
667 // frame[number_of_frames - 1 ] = on_stack_size(youngest)
668 // frame[number_of_frames - 2 ] = on_stack_size(sender(youngest))
669 // frame[number_of_frames - 3 ] = on_stack_size(sender(sender(youngest)))
670 frame_sizes[number_of_frames - 1 - index] = BytesPerWord * array->element(index)->on_stack_size(callee_parameters,
671 callee_locals,
672 index == 0,
673 popframe_extra_args);
674 // This pc doesn't have to be perfect just good enough to identify the frame
675 // as interpreted so the skeleton frame will be walkable
676 // The correct pc will be set when the skeleton frame is completely filled out
677 // The final pc we store in the loop is wrong and will be overwritten below
678 frame_pcs[number_of_frames - 1 - index ] = Interpreter::deopt_entry(vtos, 0) - frame::pc_return_offset;
679
680 callee_parameters = array->element(index)->method()->size_of_parameters();
681 callee_locals = array->element(index)->method()->max_locals();
682 popframe_extra_args = 0;
683 }
684
685 // Compute whether the root vframe returns a float or double value.
686 BasicType return_type;
687 {
688 methodHandle method(current, array->element(0)->method());
689 Bytecode_invoke invoke = Bytecode_invoke_check(method, array->element(0)->bci());
690 return_type = invoke.is_valid() ? invoke.result_type() : T_ILLEGAL;
691 }
692
693 // Compute information for handling adapters and adjusting the frame size of the caller.
694 int caller_adjustment = 0;
695
696 // Compute the amount the oldest interpreter frame will have to adjust
697 // its caller's stack by. If the caller is a compiled frame then
698 // we pretend that the callee has no parameters so that the
699 // extension counts for the full amount of locals and not just
700 // locals-parms. This is because without a c2i adapter the parm
701 // area as created by the compiled frame will not be usable by
702 // the interpreter. (Depending on the calling convention there
703 // may not even be enough space).
704
705 // QQQ I'd rather see this pushed down into last_frame_adjust
706 // and have it take the sender (aka caller).
707
708 if (!deopt_sender.is_interpreted_frame() || caller_was_method_handle) {
709 caller_adjustment = last_frame_adjust(0, callee_locals);
710 } else if (callee_locals > callee_parameters) {
711 // The caller frame may need extending to accommodate
712 // non-parameter locals of the first unpacked interpreted frame.
713 // Compute that adjustment.
714 caller_adjustment = last_frame_adjust(callee_parameters, callee_locals);
715 }
716
717 // If the sender is deoptimized the we must retrieve the address of the handler
718 // since the frame will "magically" show the original pc before the deopt
719 // and we'd undo the deopt.
720
721 frame_pcs[0] = Continuation::is_cont_barrier_frame(deoptee) ? StubRoutines::cont_returnBarrier() : deopt_sender.raw_pc();
722 if (Continuation::is_continuation_enterSpecial(deopt_sender)) {
723 ContinuationEntry::from_frame(deopt_sender)->set_argsize(0);
724 }
725
726 assert(CodeCache::find_blob(frame_pcs[0]) != nullptr, "bad pc");
727
728 #if INCLUDE_JVMCI
729 if (exceptionObject() != nullptr) {
730 current->set_exception_oop(exceptionObject());
731 exec_mode = Unpack_exception;
732 }
733 #endif
734
735 if (current->frames_to_pop_failed_realloc() > 0 && exec_mode != Unpack_uncommon_trap) {
736 assert(current->has_pending_exception(), "should have thrown OOME");
737 current->set_exception_oop(current->pending_exception());
738 current->clear_pending_exception();
739 exec_mode = Unpack_exception;
740 }
741
742 #if INCLUDE_JVMCI
743 if (current->frames_to_pop_failed_realloc() > 0) {
744 current->set_pending_monitorenter(false);
745 }
746 #endif
747
748 UnrollBlock* info = new UnrollBlock(array->frame_size() * BytesPerWord,
749 caller_adjustment * BytesPerWord,
750 caller_was_method_handle ? 0 : callee_parameters,
751 number_of_frames,
752 frame_sizes,
753 frame_pcs,
754 return_type,
755 exec_mode);
756 // On some platforms, we need a way to pass some platform dependent
757 // information to the unpacking code so the skeletal frames come out
758 // correct (initial fp value, unextended sp, ...)
759 info->set_initial_info((intptr_t) array->sender().initial_deoptimization_info());
760
761 if (array->frames() > 1) {
762 if (VerifyStack && TraceDeoptimization) {
763 tty->print_cr("Deoptimizing method containing inlining");
764 }
765 }
766
767 array->set_unroll_block(info);
768 return info;
769 }
770
771 // Called to cleanup deoptimization data structures in normal case
772 // after unpacking to stack and when stack overflow error occurs
773 void Deoptimization::cleanup_deopt_info(JavaThread *thread,
774 vframeArray *array) {
775
776 // Get array if coming from exception
777 if (array == nullptr) {
778 array = thread->vframe_array_head();
779 }
780 thread->set_vframe_array_head(nullptr);
781
782 // Free the previous UnrollBlock
783 vframeArray* old_array = thread->vframe_array_last();
784 thread->set_vframe_array_last(array);
785
786 if (old_array != nullptr) {
787 UnrollBlock* old_info = old_array->unroll_block();
788 old_array->set_unroll_block(nullptr);
789 delete old_info;
790 delete old_array;
791 }
792
793 // Deallocate any resource creating in this routine and any ResourceObjs allocated
794 // inside the vframeArray (StackValueCollections)
795
796 delete thread->deopt_mark();
797 thread->set_deopt_mark(nullptr);
798 thread->set_deopt_compiled_method(nullptr);
799
800
801 if (JvmtiExport::can_pop_frame()) {
802 // Regardless of whether we entered this routine with the pending
803 // popframe condition bit set, we should always clear it now
804 thread->clear_popframe_condition();
805 }
806
807 // unpack_frames() is called at the end of the deoptimization handler
808 // and (in C2) at the end of the uncommon trap handler. Note this fact
809 // so that an asynchronous stack walker can work again. This counter is
810 // incremented at the beginning of fetch_unroll_info() and (in C2) at
811 // the beginning of uncommon_trap().
812 thread->dec_in_deopt_handler();
813 }
814
815 // Moved from cpu directories because none of the cpus has callee save values.
816 // If a cpu implements callee save values, move this to deoptimization_<cpu>.cpp.
817 void Deoptimization::unwind_callee_save_values(frame* f, vframeArray* vframe_array) {
818
819 // This code is sort of the equivalent of C2IAdapter::setup_stack_frame back in
820 // the days we had adapter frames. When we deoptimize a situation where a
821 // compiled caller calls a compiled caller will have registers it expects
822 // to survive the call to the callee. If we deoptimize the callee the only
823 // way we can restore these registers is to have the oldest interpreter
824 // frame that we create restore these values. That is what this routine
825 // will accomplish.
826
827 // At the moment we have modified c2 to not have any callee save registers
828 // so this problem does not exist and this routine is just a place holder.
829
830 assert(f->is_interpreted_frame(), "must be interpreted");
831 }
832
833 #ifndef PRODUCT
834 static bool falls_through(Bytecodes::Code bc) {
835 switch (bc) {
836 // List may be incomplete. Here we really only care about bytecodes where compiled code
837 // can deoptimize.
838 case Bytecodes::_goto:
839 case Bytecodes::_goto_w:
840 case Bytecodes::_athrow:
841 return false;
842 default:
843 return true;
844 }
845 }
846 #endif
847
848 // Return BasicType of value being returned
849 JRT_LEAF(BasicType, Deoptimization::unpack_frames(JavaThread* thread, int exec_mode))
850 assert(thread == JavaThread::current(), "pre-condition");
851
852 // We are already active in the special DeoptResourceMark any ResourceObj's we
853 // allocate will be freed at the end of the routine.
854
855 // JRT_LEAF methods don't normally allocate handles and there is a
856 // NoHandleMark to enforce that. It is actually safe to use Handles
857 // in a JRT_LEAF method, and sometimes desirable, but to do so we
858 // must use ResetNoHandleMark to bypass the NoHandleMark, and
859 // then use a HandleMark to ensure any Handles we do create are
860 // cleaned up in this scope.
861 ResetNoHandleMark rnhm;
862 HandleMark hm(thread);
863
864 frame stub_frame = thread->last_frame();
865
866 Continuation::notify_deopt(thread, stub_frame.sp());
867
868 // Since the frame to unpack is the top frame of this thread, the vframe_array_head
869 // must point to the vframeArray for the unpack frame.
870 vframeArray* array = thread->vframe_array_head();
871 UnrollBlock* info = array->unroll_block();
872
873 // We set the last_Java frame. But the stack isn't really parsable here. So we
874 // clear it to make sure JFR understands not to try and walk stacks from events
875 // in here.
876 intptr_t* sp = thread->frame_anchor()->last_Java_sp();
877 thread->frame_anchor()->set_last_Java_sp(nullptr);
878
879 // Unpack the interpreter frames and any adapter frame (c2 only) we might create.
880 array->unpack_to_stack(stub_frame, exec_mode, info->caller_actual_parameters());
881
882 thread->frame_anchor()->set_last_Java_sp(sp);
883
884 BasicType bt = info->return_type();
885
886 // If we have an exception pending, claim that the return type is an oop
887 // so the deopt_blob does not overwrite the exception_oop.
888
889 if (exec_mode == Unpack_exception)
890 bt = T_OBJECT;
891
892 // Cleanup thread deopt data
893 cleanup_deopt_info(thread, array);
894
895 #ifndef PRODUCT
896 if (VerifyStack) {
897 ResourceMark res_mark;
898 // Clear pending exception to not break verification code (restored afterwards)
899 PreserveExceptionMark pm(thread);
900
901 thread->validate_frame_layout();
902
903 // Verify that the just-unpacked frames match the interpreter's
904 // notions of expression stack and locals
905 vframeArray* cur_array = thread->vframe_array_last();
906 RegisterMap rm(thread,
907 RegisterMap::UpdateMap::skip,
908 RegisterMap::ProcessFrames::include,
909 RegisterMap::WalkContinuation::skip);
910 rm.set_include_argument_oops(false);
911 bool is_top_frame = true;
912 int callee_size_of_parameters = 0;
913 int callee_max_locals = 0;
914 for (int i = 0; i < cur_array->frames(); i++) {
915 vframeArrayElement* el = cur_array->element(i);
916 frame* iframe = el->iframe();
917 guarantee(iframe->is_interpreted_frame(), "Wrong frame type");
918
919 // Get the oop map for this bci
920 InterpreterOopMap mask;
921 int cur_invoke_parameter_size = 0;
922 bool try_next_mask = false;
923 int next_mask_expression_stack_size = -1;
924 int top_frame_expression_stack_adjustment = 0;
925 methodHandle mh(thread, iframe->interpreter_frame_method());
926 OopMapCache::compute_one_oop_map(mh, iframe->interpreter_frame_bci(), &mask);
927 BytecodeStream str(mh, iframe->interpreter_frame_bci());
928 int max_bci = mh->code_size();
929 // Get to the next bytecode if possible
930 assert(str.bci() < max_bci, "bci in interpreter frame out of bounds");
931 // Check to see if we can grab the number of outgoing arguments
932 // at an uncommon trap for an invoke (where the compiler
933 // generates debug info before the invoke has executed)
934 Bytecodes::Code cur_code = str.next();
935 Bytecodes::Code next_code = Bytecodes::_shouldnotreachhere;
936 if (Bytecodes::is_invoke(cur_code)) {
937 Bytecode_invoke invoke(mh, iframe->interpreter_frame_bci());
938 cur_invoke_parameter_size = invoke.size_of_parameters();
939 if (i != 0 && !invoke.is_invokedynamic() && MethodHandles::has_member_arg(invoke.klass(), invoke.name())) {
940 callee_size_of_parameters++;
941 }
942 }
943 if (str.bci() < max_bci) {
944 next_code = str.next();
945 if (next_code >= 0) {
946 // The interpreter oop map generator reports results before
947 // the current bytecode has executed except in the case of
948 // calls. It seems to be hard to tell whether the compiler
949 // has emitted debug information matching the "state before"
950 // a given bytecode or the state after, so we try both
951 if (!Bytecodes::is_invoke(cur_code) && falls_through(cur_code)) {
952 // Get expression stack size for the next bytecode
953 InterpreterOopMap next_mask;
954 OopMapCache::compute_one_oop_map(mh, str.bci(), &next_mask);
955 next_mask_expression_stack_size = next_mask.expression_stack_size();
956 if (Bytecodes::is_invoke(next_code)) {
957 Bytecode_invoke invoke(mh, str.bci());
958 next_mask_expression_stack_size += invoke.size_of_parameters();
959 }
960 // Need to subtract off the size of the result type of
961 // the bytecode because this is not described in the
962 // debug info but returned to the interpreter in the TOS
963 // caching register
964 BasicType bytecode_result_type = Bytecodes::result_type(cur_code);
965 if (bytecode_result_type != T_ILLEGAL) {
966 top_frame_expression_stack_adjustment = type2size[bytecode_result_type];
967 }
968 assert(top_frame_expression_stack_adjustment >= 0, "stack adjustment must be positive");
969 try_next_mask = true;
970 }
971 }
972 }
973
974 // Verify stack depth and oops in frame
975 // This assertion may be dependent on the platform we're running on and may need modification (tested on x86 and sparc)
976 if (!(
977 /* SPARC */
978 (iframe->interpreter_frame_expression_stack_size() == mask.expression_stack_size() + callee_size_of_parameters) ||
979 /* x86 */
980 (iframe->interpreter_frame_expression_stack_size() == mask.expression_stack_size() + callee_max_locals) ||
981 (try_next_mask &&
982 (iframe->interpreter_frame_expression_stack_size() == (next_mask_expression_stack_size -
983 top_frame_expression_stack_adjustment))) ||
984 (is_top_frame && (exec_mode == Unpack_exception) && iframe->interpreter_frame_expression_stack_size() == 0) ||
985 (is_top_frame && (exec_mode == Unpack_uncommon_trap || exec_mode == Unpack_reexecute || el->should_reexecute()) &&
986 (iframe->interpreter_frame_expression_stack_size() == mask.expression_stack_size() + cur_invoke_parameter_size))
987 )) {
988 {
989 // Print out some information that will help us debug the problem
990 tty->print_cr("Wrong number of expression stack elements during deoptimization");
991 tty->print_cr(" Error occurred while verifying frame %d (0..%d, 0 is topmost)", i, cur_array->frames() - 1);
992 tty->print_cr(" Current code %s", Bytecodes::name(cur_code));
993 if (try_next_mask) {
994 tty->print_cr(" Next code %s", Bytecodes::name(next_code));
995 }
996 tty->print_cr(" Fabricated interpreter frame had %d expression stack elements",
997 iframe->interpreter_frame_expression_stack_size());
998 tty->print_cr(" Interpreter oop map had %d expression stack elements", mask.expression_stack_size());
999 tty->print_cr(" try_next_mask = %d", try_next_mask);
1000 tty->print_cr(" next_mask_expression_stack_size = %d", next_mask_expression_stack_size);
1001 tty->print_cr(" callee_size_of_parameters = %d", callee_size_of_parameters);
1002 tty->print_cr(" callee_max_locals = %d", callee_max_locals);
1003 tty->print_cr(" top_frame_expression_stack_adjustment = %d", top_frame_expression_stack_adjustment);
1004 tty->print_cr(" exec_mode = %d", exec_mode);
1005 tty->print_cr(" cur_invoke_parameter_size = %d", cur_invoke_parameter_size);
1006 tty->print_cr(" Thread = " INTPTR_FORMAT ", thread ID = %d", p2i(thread), thread->osthread()->thread_id());
1007 tty->print_cr(" Interpreted frames:");
1008 for (int k = 0; k < cur_array->frames(); k++) {
1009 vframeArrayElement* el = cur_array->element(k);
1010 tty->print_cr(" %s (bci %d)", el->method()->name_and_sig_as_C_string(), el->bci());
1011 }
1012 cur_array->print_on_2(tty);
1013 }
1014 guarantee(false, "wrong number of expression stack elements during deopt");
1015 }
1016 VerifyOopClosure verify;
1017 iframe->oops_interpreted_do(&verify, &rm, false);
1018 callee_size_of_parameters = mh->size_of_parameters();
1019 callee_max_locals = mh->max_locals();
1020 is_top_frame = false;
1021 }
1022 }
1023 #endif // !PRODUCT
1024
1025 return bt;
1026 JRT_END
1027
1028 class DeoptimizeMarkedClosure : public HandshakeClosure {
1029 public:
1030 DeoptimizeMarkedClosure() : HandshakeClosure("Deoptimize") {}
1031 void do_thread(Thread* thread) {
1032 JavaThread* jt = JavaThread::cast(thread);
1033 jt->deoptimize_marked_methods();
1034 }
1035 };
1036
1037 void Deoptimization::deoptimize_all_marked() {
1038 ResourceMark rm;
1039
1040 // Make the dependent methods not entrant
1041 CodeCache::make_marked_nmethods_deoptimized();
1042
1043 DeoptimizeMarkedClosure deopt;
1044 if (SafepointSynchronize::is_at_safepoint()) {
1045 Threads::java_threads_do(&deopt);
1046 } else {
1047 Handshake::execute(&deopt);
1048 }
1049 }
1050
1051 Deoptimization::DeoptAction Deoptimization::_unloaded_action
1052 = Deoptimization::Action_reinterpret;
1053
1054 #if INCLUDE_JVMCI
1055 template<typename CacheType>
1056 class BoxCacheBase : public CHeapObj<mtCompiler> {
1057 protected:
1058 static InstanceKlass* find_cache_klass(Thread* thread, Symbol* klass_name) {
1059 ResourceMark rm(thread);
1060 char* klass_name_str = klass_name->as_C_string();
1061 InstanceKlass* ik = SystemDictionary::find_instance_klass(thread, klass_name, Handle(), Handle());
1062 guarantee(ik != nullptr, "%s must be loaded", klass_name_str);
1063 if (!ik->is_in_error_state()) {
1064 guarantee(ik->is_initialized(), "%s must be initialized", klass_name_str);
1065 CacheType::compute_offsets(ik);
1066 }
1067 return ik;
1068 }
1069 };
1070
1071 template<typename PrimitiveType, typename CacheType, typename BoxType> class BoxCache : public BoxCacheBase<CacheType> {
1072 PrimitiveType _low;
1073 PrimitiveType _high;
1074 jobject _cache;
1075 protected:
1076 static BoxCache<PrimitiveType, CacheType, BoxType> *_singleton;
1077 BoxCache(Thread* thread) {
1078 InstanceKlass* ik = BoxCacheBase<CacheType>::find_cache_klass(thread, CacheType::symbol());
1079 if (ik->is_in_error_state()) {
1080 _low = 1;
1081 _high = 0;
1082 _cache = nullptr;
1083 } else {
1084 objArrayOop cache = CacheType::cache(ik);
1085 assert(cache->length() > 0, "Empty cache");
1086 _low = BoxType::value(cache->obj_at(0));
1087 _high = checked_cast<PrimitiveType>(_low + cache->length() - 1);
1088 _cache = JNIHandles::make_global(Handle(thread, cache));
1089 }
1090 }
1091 ~BoxCache() {
1092 JNIHandles::destroy_global(_cache);
1093 }
1094 public:
1095 static BoxCache<PrimitiveType, CacheType, BoxType>* singleton(Thread* thread) {
1096 if (_singleton == nullptr) {
1097 BoxCache<PrimitiveType, CacheType, BoxType>* s = new BoxCache<PrimitiveType, CacheType, BoxType>(thread);
1098 if (!Atomic::replace_if_null(&_singleton, s)) {
1099 delete s;
1100 }
1101 }
1102 return _singleton;
1103 }
1104 oop lookup(PrimitiveType value) {
1105 if (_low <= value && value <= _high) {
1106 int offset = checked_cast<int>(value - _low);
1107 return objArrayOop(JNIHandles::resolve_non_null(_cache))->obj_at(offset);
1108 }
1109 return nullptr;
1110 }
1111 oop lookup_raw(intptr_t raw_value, bool& cache_init_error) {
1112 if (_cache == nullptr) {
1113 cache_init_error = true;
1114 return nullptr;
1115 }
1116 // Have to cast to avoid little/big-endian problems.
1117 if (sizeof(PrimitiveType) > sizeof(jint)) {
1118 jlong value = (jlong)raw_value;
1119 return lookup(value);
1120 }
1121 PrimitiveType value = (PrimitiveType)*((jint*)&raw_value);
1122 return lookup(value);
1123 }
1124 };
1125
1126 typedef BoxCache<jint, java_lang_Integer_IntegerCache, java_lang_Integer> IntegerBoxCache;
1127 typedef BoxCache<jlong, java_lang_Long_LongCache, java_lang_Long> LongBoxCache;
1128 typedef BoxCache<jchar, java_lang_Character_CharacterCache, java_lang_Character> CharacterBoxCache;
1129 typedef BoxCache<jshort, java_lang_Short_ShortCache, java_lang_Short> ShortBoxCache;
1130 typedef BoxCache<jbyte, java_lang_Byte_ByteCache, java_lang_Byte> ByteBoxCache;
1131
1132 template<> BoxCache<jint, java_lang_Integer_IntegerCache, java_lang_Integer>* BoxCache<jint, java_lang_Integer_IntegerCache, java_lang_Integer>::_singleton = nullptr;
1133 template<> BoxCache<jlong, java_lang_Long_LongCache, java_lang_Long>* BoxCache<jlong, java_lang_Long_LongCache, java_lang_Long>::_singleton = nullptr;
1134 template<> BoxCache<jchar, java_lang_Character_CharacterCache, java_lang_Character>* BoxCache<jchar, java_lang_Character_CharacterCache, java_lang_Character>::_singleton = nullptr;
1135 template<> BoxCache<jshort, java_lang_Short_ShortCache, java_lang_Short>* BoxCache<jshort, java_lang_Short_ShortCache, java_lang_Short>::_singleton = nullptr;
1136 template<> BoxCache<jbyte, java_lang_Byte_ByteCache, java_lang_Byte>* BoxCache<jbyte, java_lang_Byte_ByteCache, java_lang_Byte>::_singleton = nullptr;
1137
1138 class BooleanBoxCache : public BoxCacheBase<java_lang_Boolean> {
1139 jobject _true_cache;
1140 jobject _false_cache;
1141 protected:
1142 static BooleanBoxCache *_singleton;
1143 BooleanBoxCache(Thread *thread) {
1144 InstanceKlass* ik = find_cache_klass(thread, java_lang_Boolean::symbol());
1145 if (ik->is_in_error_state()) {
1146 _true_cache = nullptr;
1147 _false_cache = nullptr;
1148 } else {
1149 _true_cache = JNIHandles::make_global(Handle(thread, java_lang_Boolean::get_TRUE(ik)));
1150 _false_cache = JNIHandles::make_global(Handle(thread, java_lang_Boolean::get_FALSE(ik)));
1151 }
1152 }
1153 ~BooleanBoxCache() {
1154 JNIHandles::destroy_global(_true_cache);
1155 JNIHandles::destroy_global(_false_cache);
1156 }
1157 public:
1158 static BooleanBoxCache* singleton(Thread* thread) {
1159 if (_singleton == nullptr) {
1160 BooleanBoxCache* s = new BooleanBoxCache(thread);
1161 if (!Atomic::replace_if_null(&_singleton, s)) {
1162 delete s;
1163 }
1164 }
1165 return _singleton;
1166 }
1167 oop lookup_raw(intptr_t raw_value, bool& cache_in_error) {
1168 if (_true_cache == nullptr) {
1169 cache_in_error = true;
1170 return nullptr;
1171 }
1172 // Have to cast to avoid little/big-endian problems.
1173 jboolean value = (jboolean)*((jint*)&raw_value);
1174 return lookup(value);
1175 }
1176 oop lookup(jboolean value) {
1177 if (value != 0) {
1178 return JNIHandles::resolve_non_null(_true_cache);
1179 }
1180 return JNIHandles::resolve_non_null(_false_cache);
1181 }
1182 };
1183
1184 BooleanBoxCache* BooleanBoxCache::_singleton = nullptr;
1185
1186 oop Deoptimization::get_cached_box(AutoBoxObjectValue* bv, frame* fr, RegisterMap* reg_map, bool& cache_init_error, TRAPS) {
1187 Klass* k = java_lang_Class::as_Klass(bv->klass()->as_ConstantOopReadValue()->value()());
1188 BasicType box_type = vmClasses::box_klass_type(k);
1189 if (box_type != T_OBJECT) {
1190 StackValue* value = StackValue::create_stack_value(fr, reg_map, bv->field_at(box_type == T_LONG ? 1 : 0));
1191 switch(box_type) {
1192 case T_INT: return IntegerBoxCache::singleton(THREAD)->lookup_raw(value->get_intptr(), cache_init_error);
1193 case T_CHAR: return CharacterBoxCache::singleton(THREAD)->lookup_raw(value->get_intptr(), cache_init_error);
1194 case T_SHORT: return ShortBoxCache::singleton(THREAD)->lookup_raw(value->get_intptr(), cache_init_error);
1195 case T_BYTE: return ByteBoxCache::singleton(THREAD)->lookup_raw(value->get_intptr(), cache_init_error);
1196 case T_BOOLEAN: return BooleanBoxCache::singleton(THREAD)->lookup_raw(value->get_intptr(), cache_init_error);
1197 case T_LONG: return LongBoxCache::singleton(THREAD)->lookup_raw(value->get_intptr(), cache_init_error);
1198 default:;
1199 }
1200 }
1201 return nullptr;
1202 }
1203 #endif // INCLUDE_JVMCI
1204
1205 #if COMPILER2_OR_JVMCI
1206 bool Deoptimization::realloc_objects(JavaThread* thread, frame* fr, RegisterMap* reg_map, GrowableArray<ScopeValue*>* objects, TRAPS) {
1207 Handle pending_exception(THREAD, thread->pending_exception());
1208 const char* exception_file = thread->exception_file();
1209 int exception_line = thread->exception_line();
1210 thread->clear_pending_exception();
1211
1212 bool failures = false;
1213
1214 for (int i = 0; i < objects->length(); i++) {
1215 assert(objects->at(i)->is_object(), "invalid debug information");
1216 ObjectValue* sv = (ObjectValue*) objects->at(i);
1217
1218 Klass* k = java_lang_Class::as_Klass(sv->klass()->as_ConstantOopReadValue()->value()());
1219 oop obj = nullptr;
1220
1221 bool cache_init_error = false;
1222 if (k->is_instance_klass()) {
1223 #if INCLUDE_JVMCI
1224 nmethod* nm = fr->cb()->as_nmethod_or_null();
1225 if (nm->is_compiled_by_jvmci() && sv->is_auto_box()) {
1226 AutoBoxObjectValue* abv = (AutoBoxObjectValue*) sv;
1227 obj = get_cached_box(abv, fr, reg_map, cache_init_error, THREAD);
1228 if (obj != nullptr) {
1229 // Set the flag to indicate the box came from a cache, so that we can skip the field reassignment for it.
1230 abv->set_cached(true);
1231 } else if (cache_init_error) {
1232 // Results in an OOME which is valid (as opposed to a class initialization error)
1233 // and is fine for the rare case a cache initialization failing.
1234 failures = true;
1235 }
1236 }
1237 #endif // INCLUDE_JVMCI
1238
1239 InstanceKlass* ik = InstanceKlass::cast(k);
1240 if (obj == nullptr && !cache_init_error) {
1241 InternalOOMEMark iom(THREAD);
1242 #if COMPILER2_OR_JVMCI
1243 if (EnableVectorSupport && VectorSupport::is_vector(ik)) {
1244 obj = VectorSupport::allocate_vector(ik, fr, reg_map, sv, THREAD);
1245 } else {
1246 obj = ik->allocate_instance(THREAD);
1247 }
1248 #else
1249 obj = ik->allocate_instance(THREAD);
1250 #endif // COMPILER2_OR_JVMCI
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 COMPILER2_OR_JVMCI
1581 if (EnableVectorSupport && VectorSupport::is_vector(k)) {
1582 assert(sv->field_size() == 1, "%s not a vector", k->name()->as_C_string());
1583 ScopeValue* payload = sv->field_at(0);
1584 if (payload->is_location() &&
1585 payload->as_LocationValue()->location().type() == Location::vector) {
1586 #ifndef PRODUCT
1587 if (PrintDeoptimizationDetails) {
1588 tty->print_cr("skip field reassignment for this vector - it should be assigned already");
1589 if (Verbose) {
1590 Handle obj = sv->value();
1591 k->oop_print_on(obj(), tty);
1592 }
1593 }
1594 #endif // !PRODUCT
1595 continue; // Such vector's value was already restored in VectorSupport::allocate_vector().
1596 }
1597 // Else fall-through to do assignment for scalar-replaced boxed vector representation
1598 // which could be restored after vector object allocation.
1599 }
1600 #endif /* !COMPILER2_OR_JVMCI */
1601 if (k->is_instance_klass()) {
1602 InstanceKlass* ik = InstanceKlass::cast(k);
1603 reassign_fields_by_klass(ik, fr, reg_map, sv, 0, obj(), skip_internal);
1604 } else if (k->is_typeArray_klass()) {
1605 TypeArrayKlass* ak = TypeArrayKlass::cast(k);
1606 reassign_type_array_elements(fr, reg_map, sv, (typeArrayOop) obj(), ak->element_type());
1607 } else if (k->is_objArray_klass()) {
1608 reassign_object_array_elements(fr, reg_map, sv, (objArrayOop) obj());
1609 }
1610 }
1611 // These objects may escape when we return to Interpreter after deoptimization.
1612 // We need barrier so that stores that initialize these objects can't be reordered
1613 // with subsequent stores that make these objects accessible by other threads.
1614 OrderAccess::storestore();
1615 }
1616
1617
1618 // relock objects for which synchronization was eliminated
1619 bool Deoptimization::relock_objects(JavaThread* thread, GrowableArray<MonitorInfo*>* monitors,
1620 JavaThread* deoptee_thread, frame& fr, int exec_mode, bool realloc_failures) {
1621 bool relocked_objects = false;
1622 for (int i = 0; i < monitors->length(); i++) {
1623 MonitorInfo* mon_info = monitors->at(i);
1624 if (mon_info->eliminated()) {
1625 assert(!mon_info->owner_is_scalar_replaced() || realloc_failures, "reallocation was missed");
1626 relocked_objects = true;
1627 if (!mon_info->owner_is_scalar_replaced()) {
1628 Handle obj(thread, mon_info->owner());
1629 markWord mark = obj->mark();
1630 if (exec_mode == Unpack_none) {
1631 if (LockingMode == LM_LEGACY && mark.has_locker() && fr.sp() > (intptr_t*)mark.locker()) {
1632 // With exec_mode == Unpack_none obj may be thread local and locked in
1633 // a callee frame. Make the lock in the callee a recursive lock and restore the displaced header.
1634 markWord dmw = mark.displaced_mark_helper();
1635 mark.locker()->set_displaced_header(markWord::encode((BasicLock*) nullptr));
1636 obj->set_mark(dmw);
1637 }
1638 if (mark.has_monitor()) {
1639 // defer relocking if the deoptee thread is currently waiting for obj
1640 ObjectMonitor* waiting_monitor = deoptee_thread->current_waiting_monitor();
1641 if (waiting_monitor != nullptr && waiting_monitor->object() == obj()) {
1642 assert(fr.is_deoptimized_frame(), "frame must be scheduled for deoptimization");
1643 mon_info->lock()->set_displaced_header(markWord::unused_mark());
1644 JvmtiDeferredUpdates::inc_relock_count_after_wait(deoptee_thread);
1645 continue;
1646 }
1647 }
1648 }
1649 if (LockingMode == LM_LIGHTWEIGHT) {
1650 // We have lost information about the correct state of the lock stack.
1651 // Inflate the locks instead. Enter then inflate to avoid races with
1652 // deflation.
1653 ObjectSynchronizer::enter_for(obj, nullptr, deoptee_thread);
1654 assert(mon_info->owner()->is_locked(), "object must be locked now");
1655 ObjectMonitor* mon = ObjectSynchronizer::inflate_for(deoptee_thread, obj(), ObjectSynchronizer::inflate_cause_vm_internal);
1656 assert(mon->owner() == deoptee_thread, "must be");
1657 } else {
1658 BasicLock* lock = mon_info->lock();
1659 ObjectSynchronizer::enter_for(obj, lock, deoptee_thread);
1660 assert(mon_info->owner()->is_locked(), "object must be locked now");
1661 }
1662 }
1663 }
1664 }
1665 return relocked_objects;
1666 }
1667 #endif // COMPILER2_OR_JVMCI
1668
1669 vframeArray* Deoptimization::create_vframeArray(JavaThread* thread, frame fr, RegisterMap *reg_map, GrowableArray<compiledVFrame*>* chunk, bool realloc_failures) {
1670 Events::log_deopt_message(thread, "DEOPT PACKING pc=" INTPTR_FORMAT " sp=" INTPTR_FORMAT, p2i(fr.pc()), p2i(fr.sp()));
1671
1672 // Register map for next frame (used for stack crawl). We capture
1673 // the state of the deopt'ing frame's caller. Thus if we need to
1674 // stuff a C2I adapter we can properly fill in the callee-save
1675 // register locations.
1676 frame caller = fr.sender(reg_map);
1677 int frame_size = pointer_delta_as_int(caller.sp(), fr.sp());
1678
1679 frame sender = caller;
1680
1681 // Since the Java thread being deoptimized will eventually adjust it's own stack,
1682 // the vframeArray containing the unpacking information is allocated in the C heap.
1683 // For Compiler1, the caller of the deoptimized frame is saved for use by unpack_frames().
1684 vframeArray* array = vframeArray::allocate(thread, frame_size, chunk, reg_map, sender, caller, fr, realloc_failures);
1685
1686 // Compare the vframeArray to the collected vframes
1687 assert(array->structural_compare(thread, chunk), "just checking");
1688
1689 if (TraceDeoptimization) {
1690 ResourceMark rm;
1691 stringStream st;
1692 st.print_cr("DEOPT PACKING thread=" INTPTR_FORMAT " vframeArray=" INTPTR_FORMAT, p2i(thread), p2i(array));
1693 st.print(" ");
1694 fr.print_on(&st);
1695 st.print_cr(" Virtual frames (innermost/newest first):");
1696 for (int index = 0; index < chunk->length(); index++) {
1697 compiledVFrame* vf = chunk->at(index);
1698 int bci = vf->raw_bci();
1699 const char* code_name;
1700 if (bci == SynchronizationEntryBCI) {
1701 code_name = "sync entry";
1702 } else {
1703 Bytecodes::Code code = vf->method()->code_at(bci);
1704 code_name = Bytecodes::name(code);
1705 }
1706
1707 st.print(" VFrame %d (" INTPTR_FORMAT ")", index, p2i(vf));
1708 st.print(" - %s", vf->method()->name_and_sig_as_C_string());
1709 st.print(" - %s", code_name);
1710 st.print_cr(" @ bci=%d ", bci);
1711 }
1712 tty->print_raw(st.freeze());
1713 tty->cr();
1714 }
1715
1716 return array;
1717 }
1718
1719 #if COMPILER2_OR_JVMCI
1720 void Deoptimization::pop_frames_failed_reallocs(JavaThread* thread, vframeArray* array) {
1721 // Reallocation of some scalar replaced objects failed. Record
1722 // that we need to pop all the interpreter frames for the
1723 // deoptimized compiled frame.
1724 assert(thread->frames_to_pop_failed_realloc() == 0, "missed frames to pop?");
1725 thread->set_frames_to_pop_failed_realloc(array->frames());
1726 // Unlock all monitors here otherwise the interpreter will see a
1727 // mix of locked and unlocked monitors (because of failed
1728 // reallocations of synchronized objects) and be confused.
1729 for (int i = 0; i < array->frames(); i++) {
1730 MonitorChunk* monitors = array->element(i)->monitors();
1731 if (monitors != nullptr) {
1732 // Unlock in reverse order starting from most nested monitor.
1733 for (int j = (monitors->number_of_monitors() - 1); j >= 0; j--) {
1734 BasicObjectLock* src = monitors->at(j);
1735 if (src->obj() != nullptr) {
1736 ObjectSynchronizer::exit(src->obj(), src->lock(), thread);
1737 }
1738 }
1739 array->element(i)->free_monitors();
1740 #ifdef ASSERT
1741 array->element(i)->set_removed_monitors();
1742 #endif
1743 }
1744 }
1745 }
1746 #endif
1747
1748 void Deoptimization::deoptimize_single_frame(JavaThread* thread, frame fr, Deoptimization::DeoptReason reason) {
1749 assert(fr.can_be_deoptimized(), "checking frame type");
1750
1751 gather_statistics(reason, Action_none, Bytecodes::_illegal);
1752
1753 if (LogCompilation && xtty != nullptr) {
1754 nmethod* nm = fr.cb()->as_nmethod_or_null();
1755 assert(nm != nullptr, "only compiled methods can deopt");
1756
1757 ttyLocker ttyl;
1758 xtty->begin_head("deoptimized thread='" UINTX_FORMAT "' reason='%s' pc='" INTPTR_FORMAT "'",(uintx)thread->osthread()->thread_id(), trap_reason_name(reason), p2i(fr.pc()));
1759 nm->log_identity(xtty);
1760 xtty->end_head();
1761 for (ScopeDesc* sd = nm->scope_desc_at(fr.pc()); ; sd = sd->sender()) {
1762 xtty->begin_elem("jvms bci='%d'", sd->bci());
1763 xtty->method(sd->method());
1764 xtty->end_elem();
1765 if (sd->is_top()) break;
1766 }
1767 xtty->tail("deoptimized");
1768 }
1769
1770 Continuation::notify_deopt(thread, fr.sp());
1771
1772 // Patch the compiled method so that when execution returns to it we will
1773 // deopt the execution state and return to the interpreter.
1774 fr.deoptimize(thread);
1775 }
1776
1777 void Deoptimization::deoptimize(JavaThread* thread, frame fr, DeoptReason reason) {
1778 // Deoptimize only if the frame comes from compile code.
1779 // Do not deoptimize the frame which is already patched
1780 // during the execution of the loops below.
1781 if (!fr.is_compiled_frame() || fr.is_deoptimized_frame()) {
1782 return;
1783 }
1784 ResourceMark rm;
1785 deoptimize_single_frame(thread, fr, reason);
1786 }
1787
1788 #if INCLUDE_JVMCI
1789 address Deoptimization::deoptimize_for_missing_exception_handler(nmethod* nm) {
1790 // there is no exception handler for this pc => deoptimize
1791 nm->make_not_entrant();
1792
1793 // Use Deoptimization::deoptimize for all of its side-effects:
1794 // gathering traps statistics, logging...
1795 // it also patches the return pc but we do not care about that
1796 // since we return a continuation to the deopt_blob below.
1797 JavaThread* thread = JavaThread::current();
1798 RegisterMap reg_map(thread,
1799 RegisterMap::UpdateMap::skip,
1800 RegisterMap::ProcessFrames::include,
1801 RegisterMap::WalkContinuation::skip);
1802 frame runtime_frame = thread->last_frame();
1803 frame caller_frame = runtime_frame.sender(®_map);
1804 assert(caller_frame.cb()->as_nmethod_or_null() == nm, "expect top frame compiled method");
1805 vframe* vf = vframe::new_vframe(&caller_frame, ®_map, thread);
1806 compiledVFrame* cvf = compiledVFrame::cast(vf);
1807 ScopeDesc* imm_scope = cvf->scope();
1808 MethodData* imm_mdo = get_method_data(thread, methodHandle(thread, imm_scope->method()), true);
1809 if (imm_mdo != nullptr) {
1810 // Lock to read ProfileData, and ensure lock is not broken by a safepoint
1811 MutexLocker ml(imm_mdo->extra_data_lock(), Mutex::_no_safepoint_check_flag);
1812
1813 ProfileData* pdata = imm_mdo->allocate_bci_to_data(imm_scope->bci(), nullptr);
1814 if (pdata != nullptr && pdata->is_BitData()) {
1815 BitData* bit_data = (BitData*) pdata;
1816 bit_data->set_exception_seen();
1817 }
1818 }
1819
1820 Deoptimization::deoptimize(thread, caller_frame, Deoptimization::Reason_not_compiled_exception_handler);
1821
1822 MethodData* trap_mdo = get_method_data(thread, methodHandle(thread, nm->method()), true);
1823 if (trap_mdo != nullptr) {
1824 trap_mdo->inc_trap_count(Deoptimization::Reason_not_compiled_exception_handler);
1825 }
1826
1827 return SharedRuntime::deopt_blob()->unpack_with_exception_in_tls();
1828 }
1829 #endif
1830
1831 void Deoptimization::deoptimize_frame_internal(JavaThread* thread, intptr_t* id, DeoptReason reason) {
1832 assert(thread == Thread::current() ||
1833 thread->is_handshake_safe_for(Thread::current()) ||
1834 SafepointSynchronize::is_at_safepoint(),
1835 "can only deoptimize other thread at a safepoint/handshake");
1836 // Compute frame and register map based on thread and sp.
1837 RegisterMap reg_map(thread,
1838 RegisterMap::UpdateMap::skip,
1839 RegisterMap::ProcessFrames::include,
1840 RegisterMap::WalkContinuation::skip);
1841 frame fr = thread->last_frame();
1842 while (fr.id() != id) {
1843 fr = fr.sender(®_map);
1844 }
1845 deoptimize(thread, fr, reason);
1846 }
1847
1848
1849 void Deoptimization::deoptimize_frame(JavaThread* thread, intptr_t* id, DeoptReason reason) {
1850 Thread* current = Thread::current();
1851 if (thread == current || thread->is_handshake_safe_for(current)) {
1852 Deoptimization::deoptimize_frame_internal(thread, id, reason);
1853 } else {
1854 VM_DeoptimizeFrame deopt(thread, id, reason);
1855 VMThread::execute(&deopt);
1856 }
1857 }
1858
1859 void Deoptimization::deoptimize_frame(JavaThread* thread, intptr_t* id) {
1860 deoptimize_frame(thread, id, Reason_constraint);
1861 }
1862
1863 // JVMTI PopFrame support
1864 JRT_LEAF(void, Deoptimization::popframe_preserve_args(JavaThread* thread, int bytes_to_save, void* start_address))
1865 {
1866 assert(thread == JavaThread::current(), "pre-condition");
1867 thread->popframe_preserve_args(in_ByteSize(bytes_to_save), start_address);
1868 }
1869 JRT_END
1870
1871 MethodData*
1872 Deoptimization::get_method_data(JavaThread* thread, const methodHandle& m,
1873 bool create_if_missing) {
1874 JavaThread* THREAD = thread; // For exception macros.
1875 MethodData* mdo = m()->method_data();
1876 if (mdo == nullptr && create_if_missing && !HAS_PENDING_EXCEPTION) {
1877 // Build an MDO. Ignore errors like OutOfMemory;
1878 // that simply means we won't have an MDO to update.
1879 Method::build_profiling_method_data(m, THREAD);
1880 if (HAS_PENDING_EXCEPTION) {
1881 // Only metaspace OOM is expected. No Java code executed.
1882 assert((PENDING_EXCEPTION->is_a(vmClasses::OutOfMemoryError_klass())), "we expect only an OOM error here");
1883 CLEAR_PENDING_EXCEPTION;
1884 }
1885 mdo = m()->method_data();
1886 }
1887 return mdo;
1888 }
1889
1890 #if COMPILER2_OR_JVMCI
1891 void Deoptimization::load_class_by_index(const constantPoolHandle& constant_pool, int index, TRAPS) {
1892 // In case of an unresolved klass entry, load the class.
1893 // This path is exercised from case _ldc in Parse::do_one_bytecode,
1894 // and probably nowhere else.
1895 // Even that case would benefit from simply re-interpreting the
1896 // bytecode, without paying special attention to the class index.
1897 // So this whole "class index" feature should probably be removed.
1898
1899 if (constant_pool->tag_at(index).is_unresolved_klass()) {
1900 Klass* tk = constant_pool->klass_at(index, THREAD);
1901 if (HAS_PENDING_EXCEPTION) {
1902 // Exception happened during classloading. We ignore the exception here, since it
1903 // is going to be rethrown since the current activation is going to be deoptimized and
1904 // the interpreter will re-execute the bytecode.
1905 // Do not clear probable Async Exceptions.
1906 CLEAR_PENDING_NONASYNC_EXCEPTION;
1907 // Class loading called java code which may have caused a stack
1908 // overflow. If the exception was thrown right before the return
1909 // to the runtime the stack is no longer guarded. Reguard the
1910 // stack otherwise if we return to the uncommon trap blob and the
1911 // stack bang causes a stack overflow we crash.
1912 JavaThread* jt = THREAD;
1913 bool guard_pages_enabled = jt->stack_overflow_state()->reguard_stack_if_needed();
1914 assert(guard_pages_enabled, "stack banging in uncommon trap blob may cause crash");
1915 }
1916 return;
1917 }
1918
1919 assert(!constant_pool->tag_at(index).is_symbol(),
1920 "no symbolic names here, please");
1921 }
1922
1923 #if INCLUDE_JFR
1924
1925 class DeoptReasonSerializer : public JfrSerializer {
1926 public:
1927 void serialize(JfrCheckpointWriter& writer) {
1928 writer.write_count((u4)(Deoptimization::Reason_LIMIT + 1)); // + Reason::many (-1)
1929 for (int i = -1; i < Deoptimization::Reason_LIMIT; ++i) {
1930 writer.write_key((u8)i);
1931 writer.write(Deoptimization::trap_reason_name(i));
1932 }
1933 }
1934 };
1935
1936 class DeoptActionSerializer : public JfrSerializer {
1937 public:
1938 void serialize(JfrCheckpointWriter& writer) {
1939 static const u4 nof_actions = Deoptimization::Action_LIMIT;
1940 writer.write_count(nof_actions);
1941 for (u4 i = 0; i < Deoptimization::Action_LIMIT; ++i) {
1942 writer.write_key(i);
1943 writer.write(Deoptimization::trap_action_name((int)i));
1944 }
1945 }
1946 };
1947
1948 static void register_serializers() {
1949 static int critical_section = 0;
1950 if (1 == critical_section || Atomic::cmpxchg(&critical_section, 0, 1) == 1) {
1951 return;
1952 }
1953 JfrSerializer::register_serializer(TYPE_DEOPTIMIZATIONREASON, true, new DeoptReasonSerializer());
1954 JfrSerializer::register_serializer(TYPE_DEOPTIMIZATIONACTION, true, new DeoptActionSerializer());
1955 }
1956
1957 static void post_deoptimization_event(nmethod* nm,
1958 const Method* method,
1959 int trap_bci,
1960 int instruction,
1961 Deoptimization::DeoptReason reason,
1962 Deoptimization::DeoptAction action) {
1963 assert(nm != nullptr, "invariant");
1964 assert(method != nullptr, "invariant");
1965 if (EventDeoptimization::is_enabled()) {
1966 static bool serializers_registered = false;
1967 if (!serializers_registered) {
1968 register_serializers();
1969 serializers_registered = true;
1970 }
1971 EventDeoptimization event;
1972 event.set_compileId(nm->compile_id());
1973 event.set_compiler(nm->compiler_type());
1974 event.set_method(method);
1975 event.set_lineNumber(method->line_number_from_bci(trap_bci));
1976 event.set_bci(trap_bci);
1977 event.set_instruction(instruction);
1978 event.set_reason(reason);
1979 event.set_action(action);
1980 event.commit();
1981 }
1982 }
1983
1984 #endif // INCLUDE_JFR
1985
1986 static void log_deopt(nmethod* nm, Method* tm, intptr_t pc, frame& fr, int trap_bci,
1987 const char* reason_name, const char* reason_action) {
1988 LogTarget(Debug, deoptimization) lt;
1989 if (lt.is_enabled()) {
1990 LogStream ls(lt);
1991 bool is_osr = nm->is_osr_method();
1992 ls.print("cid=%4d %s level=%d",
1993 nm->compile_id(), (is_osr ? "osr" : " "), nm->comp_level());
1994 ls.print(" %s", tm->name_and_sig_as_C_string());
1995 ls.print(" trap_bci=%d ", trap_bci);
1996 if (is_osr) {
1997 ls.print("osr_bci=%d ", nm->osr_entry_bci());
1998 }
1999 ls.print("%s ", reason_name);
2000 ls.print("%s ", reason_action);
2001 ls.print_cr("pc=" INTPTR_FORMAT " relative_pc=" INTPTR_FORMAT,
2002 pc, fr.pc() - nm->code_begin());
2003 }
2004 }
2005
2006 JRT_ENTRY(void, Deoptimization::uncommon_trap_inner(JavaThread* current, jint trap_request)) {
2007 HandleMark hm(current);
2008
2009 // uncommon_trap() is called at the beginning of the uncommon trap
2010 // handler. Note this fact before we start generating temporary frames
2011 // that can confuse an asynchronous stack walker. This counter is
2012 // decremented at the end of unpack_frames().
2013
2014 current->inc_in_deopt_handler();
2015
2016 #if INCLUDE_JVMCI
2017 // JVMCI might need to get an exception from the stack, which in turn requires the register map to be valid
2018 RegisterMap reg_map(current,
2019 RegisterMap::UpdateMap::include,
2020 RegisterMap::ProcessFrames::include,
2021 RegisterMap::WalkContinuation::skip);
2022 #else
2023 RegisterMap reg_map(current,
2024 RegisterMap::UpdateMap::skip,
2025 RegisterMap::ProcessFrames::include,
2026 RegisterMap::WalkContinuation::skip);
2027 #endif
2028 frame stub_frame = current->last_frame();
2029 frame fr = stub_frame.sender(®_map);
2030
2031 // Log a message
2032 Events::log_deopt_message(current, "Uncommon trap: trap_request=" INT32_FORMAT_X_0 " fr.pc=" INTPTR_FORMAT " relative=" INTPTR_FORMAT,
2033 trap_request, p2i(fr.pc()), fr.pc() - fr.cb()->code_begin());
2034
2035 {
2036 ResourceMark rm;
2037
2038 DeoptReason reason = trap_request_reason(trap_request);
2039 DeoptAction action = trap_request_action(trap_request);
2040 #if INCLUDE_JVMCI
2041 int debug_id = trap_request_debug_id(trap_request);
2042 #endif
2043 jint unloaded_class_index = trap_request_index(trap_request); // CP idx or -1
2044
2045 vframe* vf = vframe::new_vframe(&fr, ®_map, current);
2046 compiledVFrame* cvf = compiledVFrame::cast(vf);
2047
2048 nmethod* nm = cvf->code();
2049
2050 ScopeDesc* trap_scope = cvf->scope();
2051
2052 bool is_receiver_constraint_failure = COMPILER2_PRESENT(VerifyReceiverTypes &&) (reason == Deoptimization::Reason_receiver_constraint);
2053
2054 if (is_receiver_constraint_failure) {
2055 tty->print_cr(" bci=%d pc=" INTPTR_FORMAT ", relative_pc=" INTPTR_FORMAT ", method=%s" JVMCI_ONLY(", debug_id=%d"),
2056 trap_scope->bci(), p2i(fr.pc()), fr.pc() - nm->code_begin(), trap_scope->method()->name_and_sig_as_C_string()
2057 JVMCI_ONLY(COMMA debug_id));
2058 }
2059
2060 methodHandle trap_method(current, trap_scope->method());
2061 int trap_bci = trap_scope->bci();
2062 #if INCLUDE_JVMCI
2063 jlong speculation = current->pending_failed_speculation();
2064 if (nm->is_compiled_by_jvmci()) {
2065 nm->update_speculation(current);
2066 } else {
2067 assert(speculation == 0, "There should not be a speculation for methods compiled by non-JVMCI compilers");
2068 }
2069
2070 if (trap_bci == SynchronizationEntryBCI) {
2071 trap_bci = 0;
2072 current->set_pending_monitorenter(true);
2073 }
2074
2075 if (reason == Deoptimization::Reason_transfer_to_interpreter) {
2076 current->set_pending_transfer_to_interpreter(true);
2077 }
2078 #endif
2079
2080 Bytecodes::Code trap_bc = trap_method->java_code_at(trap_bci);
2081 // Record this event in the histogram.
2082 gather_statistics(reason, action, trap_bc);
2083
2084 // Ensure that we can record deopt. history:
2085 // Need MDO to record RTM code generation state.
2086 bool create_if_missing = ProfileTraps RTM_OPT_ONLY( || UseRTMLocking );
2087
2088 methodHandle profiled_method;
2089 #if INCLUDE_JVMCI
2090 if (nm->is_compiled_by_jvmci()) {
2091 profiled_method = methodHandle(current, nm->method());
2092 } else {
2093 profiled_method = trap_method;
2094 }
2095 #else
2096 profiled_method = trap_method;
2097 #endif
2098
2099 MethodData* trap_mdo =
2100 get_method_data(current, profiled_method, create_if_missing);
2101
2102 { // Log Deoptimization event for JFR, UL and event system
2103 Method* tm = trap_method();
2104 const char* reason_name = trap_reason_name(reason);
2105 const char* reason_action = trap_action_name(action);
2106 intptr_t pc = p2i(fr.pc());
2107
2108 JFR_ONLY(post_deoptimization_event(nm, tm, trap_bci, trap_bc, reason, action);)
2109 log_deopt(nm, tm, pc, fr, trap_bci, reason_name, reason_action);
2110 Events::log_deopt_message(current, "Uncommon trap: reason=%s action=%s pc=" INTPTR_FORMAT " method=%s @ %d %s",
2111 reason_name, reason_action, pc,
2112 tm->name_and_sig_as_C_string(), trap_bci, nm->compiler_name());
2113 }
2114
2115 // Print a bunch of diagnostics, if requested.
2116 if (TraceDeoptimization || LogCompilation || is_receiver_constraint_failure) {
2117 ResourceMark rm;
2118
2119 // Lock to read ProfileData, and ensure lock is not broken by a safepoint
2120 // We must do this already now, since we cannot acquire this lock while
2121 // holding the tty lock (lock ordering by rank).
2122 MutexLocker ml(trap_mdo->extra_data_lock(), Mutex::_no_safepoint_check_flag);
2123
2124 ttyLocker ttyl;
2125
2126 char buf[100];
2127 if (xtty != nullptr) {
2128 xtty->begin_head("uncommon_trap thread='" UINTX_FORMAT "' %s",
2129 os::current_thread_id(),
2130 format_trap_request(buf, sizeof(buf), trap_request));
2131 #if INCLUDE_JVMCI
2132 if (speculation != 0) {
2133 xtty->print(" speculation='" JLONG_FORMAT "'", speculation);
2134 }
2135 #endif
2136 nm->log_identity(xtty);
2137 }
2138 Symbol* class_name = nullptr;
2139 bool unresolved = false;
2140 if (unloaded_class_index >= 0) {
2141 constantPoolHandle constants (current, trap_method->constants());
2142 if (constants->tag_at(unloaded_class_index).is_unresolved_klass()) {
2143 class_name = constants->klass_name_at(unloaded_class_index);
2144 unresolved = true;
2145 if (xtty != nullptr)
2146 xtty->print(" unresolved='1'");
2147 } else if (constants->tag_at(unloaded_class_index).is_symbol()) {
2148 class_name = constants->symbol_at(unloaded_class_index);
2149 }
2150 if (xtty != nullptr)
2151 xtty->name(class_name);
2152 }
2153 if (xtty != nullptr && trap_mdo != nullptr && (int)reason < (int)MethodData::_trap_hist_limit) {
2154 // Dump the relevant MDO state.
2155 // This is the deopt count for the current reason, any previous
2156 // reasons or recompiles seen at this point.
2157 int dcnt = trap_mdo->trap_count(reason);
2158 if (dcnt != 0)
2159 xtty->print(" count='%d'", dcnt);
2160
2161 // We need to lock to read the ProfileData. But to keep the locks ordered, we need to
2162 // lock extra_data_lock before the tty lock.
2163 ProfileData* pdata = trap_mdo->bci_to_data(trap_bci);
2164 int dos = (pdata == nullptr)? 0: pdata->trap_state();
2165 if (dos != 0) {
2166 xtty->print(" state='%s'", format_trap_state(buf, sizeof(buf), dos));
2167 if (trap_state_is_recompiled(dos)) {
2168 int recnt2 = trap_mdo->overflow_recompile_count();
2169 if (recnt2 != 0)
2170 xtty->print(" recompiles2='%d'", recnt2);
2171 }
2172 }
2173 }
2174 if (xtty != nullptr) {
2175 xtty->stamp();
2176 xtty->end_head();
2177 }
2178 if (TraceDeoptimization) { // make noise on the tty
2179 stringStream st;
2180 st.print("UNCOMMON TRAP method=%s", trap_scope->method()->name_and_sig_as_C_string());
2181 st.print(" bci=%d pc=" INTPTR_FORMAT ", relative_pc=" INTPTR_FORMAT JVMCI_ONLY(", debug_id=%d"),
2182 trap_scope->bci(), p2i(fr.pc()), fr.pc() - nm->code_begin() JVMCI_ONLY(COMMA debug_id));
2183 st.print(" compiler=%s compile_id=%d", nm->compiler_name(), nm->compile_id());
2184 #if INCLUDE_JVMCI
2185 if (nm->is_compiled_by_jvmci()) {
2186 const char* installed_code_name = nm->jvmci_name();
2187 if (installed_code_name != nullptr) {
2188 st.print(" (JVMCI: installed code name=%s) ", installed_code_name);
2189 }
2190 }
2191 #endif
2192 st.print(" (@" INTPTR_FORMAT ") thread=" UINTX_FORMAT " reason=%s action=%s unloaded_class_index=%d" JVMCI_ONLY(" debug_id=%d"),
2193 p2i(fr.pc()),
2194 os::current_thread_id(),
2195 trap_reason_name(reason),
2196 trap_action_name(action),
2197 unloaded_class_index
2198 #if INCLUDE_JVMCI
2199 , debug_id
2200 #endif
2201 );
2202 if (class_name != nullptr) {
2203 st.print(unresolved ? " unresolved class: " : " symbol: ");
2204 class_name->print_symbol_on(&st);
2205 }
2206 st.cr();
2207 tty->print_raw(st.freeze());
2208 }
2209 if (xtty != nullptr) {
2210 // Log the precise location of the trap.
2211 for (ScopeDesc* sd = trap_scope; ; sd = sd->sender()) {
2212 xtty->begin_elem("jvms bci='%d'", sd->bci());
2213 xtty->method(sd->method());
2214 xtty->end_elem();
2215 if (sd->is_top()) break;
2216 }
2217 xtty->tail("uncommon_trap");
2218 }
2219 }
2220 // (End diagnostic printout.)
2221
2222 if (is_receiver_constraint_failure) {
2223 fatal("missing receiver type check");
2224 }
2225
2226 // Load class if necessary
2227 if (unloaded_class_index >= 0) {
2228 constantPoolHandle constants(current, trap_method->constants());
2229 load_class_by_index(constants, unloaded_class_index, THREAD);
2230 }
2231
2232 // Flush the nmethod if necessary and desirable.
2233 //
2234 // We need to avoid situations where we are re-flushing the nmethod
2235 // because of a hot deoptimization site. Repeated flushes at the same
2236 // point need to be detected by the compiler and avoided. If the compiler
2237 // cannot avoid them (or has a bug and "refuses" to avoid them), this
2238 // module must take measures to avoid an infinite cycle of recompilation
2239 // and deoptimization. There are several such measures:
2240 //
2241 // 1. If a recompilation is ordered a second time at some site X
2242 // and for the same reason R, the action is adjusted to 'reinterpret',
2243 // to give the interpreter time to exercise the method more thoroughly.
2244 // If this happens, the method's overflow_recompile_count is incremented.
2245 //
2246 // 2. If the compiler fails to reduce the deoptimization rate, then
2247 // the method's overflow_recompile_count will begin to exceed the set
2248 // limit PerBytecodeRecompilationCutoff. If this happens, the action
2249 // is adjusted to 'make_not_compilable', and the method is abandoned
2250 // to the interpreter. This is a performance hit for hot methods,
2251 // but is better than a disastrous infinite cycle of recompilations.
2252 // (Actually, only the method containing the site X is abandoned.)
2253 //
2254 // 3. In parallel with the previous measures, if the total number of
2255 // recompilations of a method exceeds the much larger set limit
2256 // PerMethodRecompilationCutoff, the method is abandoned.
2257 // This should only happen if the method is very large and has
2258 // many "lukewarm" deoptimizations. The code which enforces this
2259 // limit is elsewhere (class nmethod, class Method).
2260 //
2261 // Note that the per-BCI 'is_recompiled' bit gives the compiler one chance
2262 // to recompile at each bytecode independently of the per-BCI cutoff.
2263 //
2264 // The decision to update code is up to the compiler, and is encoded
2265 // in the Action_xxx code. If the compiler requests Action_none
2266 // no trap state is changed, no compiled code is changed, and the
2267 // computation suffers along in the interpreter.
2268 //
2269 // The other action codes specify various tactics for decompilation
2270 // and recompilation. Action_maybe_recompile is the loosest, and
2271 // allows the compiled code to stay around until enough traps are seen,
2272 // and until the compiler gets around to recompiling the trapping method.
2273 //
2274 // The other actions cause immediate removal of the present code.
2275
2276 // Traps caused by injected profile shouldn't pollute trap counts.
2277 bool injected_profile_trap = trap_method->has_injected_profile() &&
2278 (reason == Reason_intrinsic || reason == Reason_unreached);
2279
2280 bool update_trap_state = (reason != Reason_tenured) && !injected_profile_trap;
2281 bool make_not_entrant = false;
2282 bool make_not_compilable = false;
2283 bool reprofile = false;
2284 switch (action) {
2285 case Action_none:
2286 // Keep the old code.
2287 update_trap_state = false;
2288 break;
2289 case Action_maybe_recompile:
2290 // Do not need to invalidate the present code, but we can
2291 // initiate another
2292 // Start compiler without (necessarily) invalidating the nmethod.
2293 // The system will tolerate the old code, but new code should be
2294 // generated when possible.
2295 break;
2296 case Action_reinterpret:
2297 // Go back into the interpreter for a while, and then consider
2298 // recompiling form scratch.
2299 make_not_entrant = true;
2300 // Reset invocation counter for outer most method.
2301 // This will allow the interpreter to exercise the bytecodes
2302 // for a while before recompiling.
2303 // By contrast, Action_make_not_entrant is immediate.
2304 //
2305 // Note that the compiler will track null_check, null_assert,
2306 // range_check, and class_check events and log them as if they
2307 // had been traps taken from compiled code. This will update
2308 // the MDO trap history so that the next compilation will
2309 // properly detect hot trap sites.
2310 reprofile = true;
2311 break;
2312 case Action_make_not_entrant:
2313 // Request immediate recompilation, and get rid of the old code.
2314 // Make them not entrant, so next time they are called they get
2315 // recompiled. Unloaded classes are loaded now so recompile before next
2316 // time they are called. Same for uninitialized. The interpreter will
2317 // link the missing class, if any.
2318 make_not_entrant = true;
2319 break;
2320 case Action_make_not_compilable:
2321 // Give up on compiling this method at all.
2322 make_not_entrant = true;
2323 make_not_compilable = true;
2324 break;
2325 default:
2326 ShouldNotReachHere();
2327 }
2328
2329 // Setting +ProfileTraps fixes the following, on all platforms:
2330 // 4852688: ProfileInterpreter is off by default for ia64. The result is
2331 // infinite heroic-opt-uncommon-trap/deopt/recompile cycles, since the
2332 // recompile relies on a MethodData* to record heroic opt failures.
2333
2334 // Whether the interpreter is producing MDO data or not, we also need
2335 // to use the MDO to detect hot deoptimization points and control
2336 // aggressive optimization.
2337 bool inc_recompile_count = false;
2338
2339 // Lock to read ProfileData, and ensure lock is not broken by a safepoint
2340 ConditionalMutexLocker ml((trap_mdo != nullptr) ? trap_mdo->extra_data_lock() : nullptr,
2341 (trap_mdo != nullptr),
2342 Mutex::_no_safepoint_check_flag);
2343 ProfileData* pdata = nullptr;
2344 if (ProfileTraps && CompilerConfig::is_c2_or_jvmci_compiler_enabled() && update_trap_state && trap_mdo != nullptr) {
2345 assert(trap_mdo == get_method_data(current, profiled_method, false), "sanity");
2346 uint this_trap_count = 0;
2347 bool maybe_prior_trap = false;
2348 bool maybe_prior_recompile = false;
2349
2350 pdata = query_update_method_data(trap_mdo, trap_bci, reason, true,
2351 #if INCLUDE_JVMCI
2352 nm->is_compiled_by_jvmci() && nm->is_osr_method(),
2353 #endif
2354 nm->method(),
2355 //outputs:
2356 this_trap_count,
2357 maybe_prior_trap,
2358 maybe_prior_recompile);
2359 // Because the interpreter also counts null, div0, range, and class
2360 // checks, these traps from compiled code are double-counted.
2361 // This is harmless; it just means that the PerXTrapLimit values
2362 // are in effect a little smaller than they look.
2363
2364 DeoptReason per_bc_reason = reason_recorded_per_bytecode_if_any(reason);
2365 if (per_bc_reason != Reason_none) {
2366 // Now take action based on the partially known per-BCI history.
2367 if (maybe_prior_trap
2368 && this_trap_count >= (uint)PerBytecodeTrapLimit) {
2369 // If there are too many traps at this BCI, force a recompile.
2370 // This will allow the compiler to see the limit overflow, and
2371 // take corrective action, if possible. The compiler generally
2372 // does not use the exact PerBytecodeTrapLimit value, but instead
2373 // changes its tactics if it sees any traps at all. This provides
2374 // a little hysteresis, delaying a recompile until a trap happens
2375 // several times.
2376 //
2377 // Actually, since there is only one bit of counter per BCI,
2378 // the possible per-BCI counts are {0,1,(per-method count)}.
2379 // This produces accurate results if in fact there is only
2380 // one hot trap site, but begins to get fuzzy if there are
2381 // many sites. For example, if there are ten sites each
2382 // trapping two or more times, they each get the blame for
2383 // all of their traps.
2384 make_not_entrant = true;
2385 }
2386
2387 // Detect repeated recompilation at the same BCI, and enforce a limit.
2388 if (make_not_entrant && maybe_prior_recompile) {
2389 // More than one recompile at this point.
2390 inc_recompile_count = maybe_prior_trap;
2391 }
2392 } else {
2393 // For reasons which are not recorded per-bytecode, we simply
2394 // force recompiles unconditionally.
2395 // (Note that PerMethodRecompilationCutoff is enforced elsewhere.)
2396 make_not_entrant = true;
2397 }
2398
2399 // Go back to the compiler if there are too many traps in this method.
2400 if (this_trap_count >= per_method_trap_limit(reason)) {
2401 // If there are too many traps in this method, force a recompile.
2402 // This will allow the compiler to see the limit overflow, and
2403 // take corrective action, if possible.
2404 // (This condition is an unlikely backstop only, because the
2405 // PerBytecodeTrapLimit is more likely to take effect first,
2406 // if it is applicable.)
2407 make_not_entrant = true;
2408 }
2409
2410 // Here's more hysteresis: If there has been a recompile at
2411 // this trap point already, run the method in the interpreter
2412 // for a while to exercise it more thoroughly.
2413 if (make_not_entrant && maybe_prior_recompile && maybe_prior_trap) {
2414 reprofile = true;
2415 }
2416 }
2417
2418 // Take requested actions on the method:
2419
2420 // Recompile
2421 if (make_not_entrant) {
2422 if (!nm->make_not_entrant()) {
2423 return; // the call did not change nmethod's state
2424 }
2425
2426 if (pdata != nullptr) {
2427 // Record the recompilation event, if any.
2428 int tstate0 = pdata->trap_state();
2429 int tstate1 = trap_state_set_recompiled(tstate0, true);
2430 if (tstate1 != tstate0)
2431 pdata->set_trap_state(tstate1);
2432 }
2433
2434 #if INCLUDE_RTM_OPT
2435 // Restart collecting RTM locking abort statistic if the method
2436 // is recompiled for a reason other than RTM state change.
2437 // Assume that in new recompiled code the statistic could be different,
2438 // for example, due to different inlining.
2439 if ((reason != Reason_rtm_state_change) && (trap_mdo != nullptr) &&
2440 UseRTMDeopt && (nm->rtm_state() != ProfileRTM)) {
2441 trap_mdo->atomic_set_rtm_state(ProfileRTM);
2442 }
2443 #endif
2444 // For code aging we count traps separately here, using make_not_entrant()
2445 // as a guard against simultaneous deopts in multiple threads.
2446 if (reason == Reason_tenured && trap_mdo != nullptr) {
2447 trap_mdo->inc_tenure_traps();
2448 }
2449 }
2450
2451 if (inc_recompile_count) {
2452 trap_mdo->inc_overflow_recompile_count();
2453 if ((uint)trap_mdo->overflow_recompile_count() >
2454 (uint)PerBytecodeRecompilationCutoff) {
2455 // Give up on the method containing the bad BCI.
2456 if (trap_method() == nm->method()) {
2457 make_not_compilable = true;
2458 } else {
2459 trap_method->set_not_compilable("overflow_recompile_count > PerBytecodeRecompilationCutoff", CompLevel_full_optimization);
2460 // But give grace to the enclosing nm->method().
2461 }
2462 }
2463 }
2464
2465 // Reprofile
2466 if (reprofile) {
2467 CompilationPolicy::reprofile(trap_scope, nm->is_osr_method());
2468 }
2469
2470 // Give up compiling
2471 if (make_not_compilable && !nm->method()->is_not_compilable(CompLevel_full_optimization)) {
2472 assert(make_not_entrant, "consistent");
2473 nm->method()->set_not_compilable("give up compiling", CompLevel_full_optimization);
2474 }
2475
2476 if (ProfileExceptionHandlers && trap_mdo != nullptr) {
2477 BitData* exception_handler_data = trap_mdo->exception_handler_bci_to_data_or_null(trap_bci);
2478 if (exception_handler_data != nullptr) {
2479 // uncommon trap at the start of an exception handler.
2480 // C2 generates these for un-entered exception handlers.
2481 // mark the handler as entered to avoid generating
2482 // another uncommon trap the next time the handler is compiled
2483 exception_handler_data->set_exception_handler_entered();
2484 }
2485 }
2486
2487 } // Free marked resources
2488
2489 }
2490 JRT_END
2491
2492 ProfileData*
2493 Deoptimization::query_update_method_data(MethodData* trap_mdo,
2494 int trap_bci,
2495 Deoptimization::DeoptReason reason,
2496 bool update_total_trap_count,
2497 #if INCLUDE_JVMCI
2498 bool is_osr,
2499 #endif
2500 Method* compiled_method,
2501 //outputs:
2502 uint& ret_this_trap_count,
2503 bool& ret_maybe_prior_trap,
2504 bool& ret_maybe_prior_recompile) {
2505 trap_mdo->check_extra_data_locked();
2506
2507 bool maybe_prior_trap = false;
2508 bool maybe_prior_recompile = false;
2509 uint this_trap_count = 0;
2510 if (update_total_trap_count) {
2511 uint idx = reason;
2512 #if INCLUDE_JVMCI
2513 if (is_osr) {
2514 // Upper half of history array used for traps in OSR compilations
2515 idx += Reason_TRAP_HISTORY_LENGTH;
2516 }
2517 #endif
2518 uint prior_trap_count = trap_mdo->trap_count(idx);
2519 this_trap_count = trap_mdo->inc_trap_count(idx);
2520
2521 // If the runtime cannot find a place to store trap history,
2522 // it is estimated based on the general condition of the method.
2523 // If the method has ever been recompiled, or has ever incurred
2524 // a trap with the present reason , then this BCI is assumed
2525 // (pessimistically) to be the culprit.
2526 maybe_prior_trap = (prior_trap_count != 0);
2527 maybe_prior_recompile = (trap_mdo->decompile_count() != 0);
2528 }
2529 ProfileData* pdata = nullptr;
2530
2531
2532 // For reasons which are recorded per bytecode, we check per-BCI data.
2533 DeoptReason per_bc_reason = reason_recorded_per_bytecode_if_any(reason);
2534 assert(per_bc_reason != Reason_none || update_total_trap_count, "must be");
2535 if (per_bc_reason != Reason_none) {
2536 // Find the profile data for this BCI. If there isn't one,
2537 // try to allocate one from the MDO's set of spares.
2538 // This will let us detect a repeated trap at this point.
2539 pdata = trap_mdo->allocate_bci_to_data(trap_bci, reason_is_speculate(reason) ? compiled_method : nullptr);
2540
2541 if (pdata != nullptr) {
2542 if (reason_is_speculate(reason) && !pdata->is_SpeculativeTrapData()) {
2543 if (LogCompilation && xtty != nullptr) {
2544 ttyLocker ttyl;
2545 // no more room for speculative traps in this MDO
2546 xtty->elem("speculative_traps_oom");
2547 }
2548 }
2549 // Query the trap state of this profile datum.
2550 int tstate0 = pdata->trap_state();
2551 if (!trap_state_has_reason(tstate0, per_bc_reason))
2552 maybe_prior_trap = false;
2553 if (!trap_state_is_recompiled(tstate0))
2554 maybe_prior_recompile = false;
2555
2556 // Update the trap state of this profile datum.
2557 int tstate1 = tstate0;
2558 // Record the reason.
2559 tstate1 = trap_state_add_reason(tstate1, per_bc_reason);
2560 // Store the updated state on the MDO, for next time.
2561 if (tstate1 != tstate0)
2562 pdata->set_trap_state(tstate1);
2563 } else {
2564 if (LogCompilation && xtty != nullptr) {
2565 ttyLocker ttyl;
2566 // Missing MDP? Leave a small complaint in the log.
2567 xtty->elem("missing_mdp bci='%d'", trap_bci);
2568 }
2569 }
2570 }
2571
2572 // Return results:
2573 ret_this_trap_count = this_trap_count;
2574 ret_maybe_prior_trap = maybe_prior_trap;
2575 ret_maybe_prior_recompile = maybe_prior_recompile;
2576 return pdata;
2577 }
2578
2579 void
2580 Deoptimization::update_method_data_from_interpreter(MethodData* trap_mdo, int trap_bci, int reason) {
2581 ResourceMark rm;
2582 // Ignored outputs:
2583 uint ignore_this_trap_count;
2584 bool ignore_maybe_prior_trap;
2585 bool ignore_maybe_prior_recompile;
2586 assert(!reason_is_speculate(reason), "reason speculate only used by compiler");
2587 // JVMCI uses the total counts to determine if deoptimizations are happening too frequently -> do not adjust total counts
2588 bool update_total_counts = true JVMCI_ONLY( && !UseJVMCICompiler);
2589
2590 // Lock to read ProfileData, and ensure lock is not broken by a safepoint
2591 MutexLocker ml(trap_mdo->extra_data_lock(), Mutex::_no_safepoint_check_flag);
2592
2593 query_update_method_data(trap_mdo, trap_bci,
2594 (DeoptReason)reason,
2595 update_total_counts,
2596 #if INCLUDE_JVMCI
2597 false,
2598 #endif
2599 nullptr,
2600 ignore_this_trap_count,
2601 ignore_maybe_prior_trap,
2602 ignore_maybe_prior_recompile);
2603 }
2604
2605 Deoptimization::UnrollBlock* Deoptimization::uncommon_trap(JavaThread* current, jint trap_request, jint exec_mode) {
2606 // Enable WXWrite: current function is called from methods compiled by C2 directly
2607 MACOS_AARCH64_ONLY(ThreadWXEnable wx(WXWrite, current));
2608
2609 // Still in Java no safepoints
2610 {
2611 // This enters VM and may safepoint
2612 uncommon_trap_inner(current, trap_request);
2613 }
2614 HandleMark hm(current);
2615 return fetch_unroll_info_helper(current, exec_mode);
2616 }
2617
2618 // Local derived constants.
2619 // Further breakdown of DataLayout::trap_state, as promised by DataLayout.
2620 const int DS_REASON_MASK = ((uint)DataLayout::trap_mask) >> 1;
2621 const int DS_RECOMPILE_BIT = DataLayout::trap_mask - DS_REASON_MASK;
2622
2623 //---------------------------trap_state_reason---------------------------------
2624 Deoptimization::DeoptReason
2625 Deoptimization::trap_state_reason(int trap_state) {
2626 // This assert provides the link between the width of DataLayout::trap_bits
2627 // and the encoding of "recorded" reasons. It ensures there are enough
2628 // bits to store all needed reasons in the per-BCI MDO profile.
2629 assert(DS_REASON_MASK >= Reason_RECORDED_LIMIT, "enough bits");
2630 int recompile_bit = (trap_state & DS_RECOMPILE_BIT);
2631 trap_state -= recompile_bit;
2632 if (trap_state == DS_REASON_MASK) {
2633 return Reason_many;
2634 } else {
2635 assert((int)Reason_none == 0, "state=0 => Reason_none");
2636 return (DeoptReason)trap_state;
2637 }
2638 }
2639 //-------------------------trap_state_has_reason-------------------------------
2640 int Deoptimization::trap_state_has_reason(int trap_state, int reason) {
2641 assert(reason_is_recorded_per_bytecode((DeoptReason)reason), "valid reason");
2642 assert(DS_REASON_MASK >= Reason_RECORDED_LIMIT, "enough bits");
2643 int recompile_bit = (trap_state & DS_RECOMPILE_BIT);
2644 trap_state -= recompile_bit;
2645 if (trap_state == DS_REASON_MASK) {
2646 return -1; // true, unspecifically (bottom of state lattice)
2647 } else if (trap_state == reason) {
2648 return 1; // true, definitely
2649 } else if (trap_state == 0) {
2650 return 0; // false, definitely (top of state lattice)
2651 } else {
2652 return 0; // false, definitely
2653 }
2654 }
2655 //-------------------------trap_state_add_reason-------------------------------
2656 int Deoptimization::trap_state_add_reason(int trap_state, int reason) {
2657 assert(reason_is_recorded_per_bytecode((DeoptReason)reason) || reason == Reason_many, "valid reason");
2658 int recompile_bit = (trap_state & DS_RECOMPILE_BIT);
2659 trap_state -= recompile_bit;
2660 if (trap_state == DS_REASON_MASK) {
2661 return trap_state + recompile_bit; // already at state lattice bottom
2662 } else if (trap_state == reason) {
2663 return trap_state + recompile_bit; // the condition is already true
2664 } else if (trap_state == 0) {
2665 return reason + recompile_bit; // no condition has yet been true
2666 } else {
2667 return DS_REASON_MASK + recompile_bit; // fall to state lattice bottom
2668 }
2669 }
2670 //-----------------------trap_state_is_recompiled------------------------------
2671 bool Deoptimization::trap_state_is_recompiled(int trap_state) {
2672 return (trap_state & DS_RECOMPILE_BIT) != 0;
2673 }
2674 //-----------------------trap_state_set_recompiled-----------------------------
2675 int Deoptimization::trap_state_set_recompiled(int trap_state, bool z) {
2676 if (z) return trap_state | DS_RECOMPILE_BIT;
2677 else return trap_state & ~DS_RECOMPILE_BIT;
2678 }
2679 //---------------------------format_trap_state---------------------------------
2680 // This is used for debugging and diagnostics, including LogFile output.
2681 const char* Deoptimization::format_trap_state(char* buf, size_t buflen,
2682 int trap_state) {
2683 assert(buflen > 0, "sanity");
2684 DeoptReason reason = trap_state_reason(trap_state);
2685 bool recomp_flag = trap_state_is_recompiled(trap_state);
2686 // Re-encode the state from its decoded components.
2687 int decoded_state = 0;
2688 if (reason_is_recorded_per_bytecode(reason) || reason == Reason_many)
2689 decoded_state = trap_state_add_reason(decoded_state, reason);
2690 if (recomp_flag)
2691 decoded_state = trap_state_set_recompiled(decoded_state, recomp_flag);
2692 // If the state re-encodes properly, format it symbolically.
2693 // Because this routine is used for debugging and diagnostics,
2694 // be robust even if the state is a strange value.
2695 size_t len;
2696 if (decoded_state != trap_state) {
2697 // Random buggy state that doesn't decode??
2698 len = jio_snprintf(buf, buflen, "#%d", trap_state);
2699 } else {
2700 len = jio_snprintf(buf, buflen, "%s%s",
2701 trap_reason_name(reason),
2702 recomp_flag ? " recompiled" : "");
2703 }
2704 return buf;
2705 }
2706
2707
2708 //--------------------------------statics--------------------------------------
2709 const char* Deoptimization::_trap_reason_name[] = {
2710 // Note: Keep this in sync. with enum DeoptReason.
2711 "none",
2712 "null_check",
2713 "null_assert" JVMCI_ONLY("_or_unreached0"),
2714 "range_check",
2715 "class_check",
2716 "array_check",
2717 "intrinsic" JVMCI_ONLY("_or_type_checked_inlining"),
2718 "bimorphic" JVMCI_ONLY("_or_optimized_type_check"),
2719 "profile_predicate",
2720 "unloaded",
2721 "uninitialized",
2722 "initialized",
2723 "unreached",
2724 "unhandled",
2725 "constraint",
2726 "div0_check",
2727 "age",
2728 "predicate",
2729 "loop_limit_check",
2730 "speculate_class_check",
2731 "speculate_null_check",
2732 "speculate_null_assert",
2733 "rtm_state_change",
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