1 /*
2 * Copyright (c) 1997, 2021, 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 "jvm.h"
27 #include "classfile/javaClasses.inline.hpp"
28 #include "classfile/symbolTable.hpp"
29 #include "classfile/systemDictionary.hpp"
30 #include "classfile/vmClasses.hpp"
31 #include "code/codeCache.hpp"
32 #include "code/debugInfoRec.hpp"
33 #include "code/nmethod.hpp"
34 #include "code/pcDesc.hpp"
35 #include "code/scopeDesc.hpp"
36 #include "compiler/compilationPolicy.hpp"
37 #include "gc/shared/collectedHeap.hpp"
38 #include "interpreter/bytecode.hpp"
39 #include "interpreter/interpreter.hpp"
40 #include "interpreter/oopMapCache.hpp"
41 #include "memory/allocation.inline.hpp"
42 #include "memory/oopFactory.hpp"
43 #include "memory/resourceArea.hpp"
44 #include "memory/universe.hpp"
45 #include "oops/constantPool.hpp"
46 #include "oops/method.hpp"
47 #include "oops/objArrayKlass.hpp"
48 #include "oops/objArrayOop.inline.hpp"
49 #include "oops/oop.inline.hpp"
50 #include "oops/fieldStreams.inline.hpp"
51 #include "oops/typeArrayOop.inline.hpp"
52 #include "oops/verifyOopClosure.hpp"
53 #include "prims/jvmtiDeferredUpdates.hpp"
54 #include "prims/jvmtiExport.hpp"
55 #include "prims/jvmtiThreadState.hpp"
56 #include "prims/vectorSupport.hpp"
57 #include "prims/methodHandles.hpp"
58 #include "runtime/atomic.hpp"
59 #include "runtime/biasedLocking.hpp"
60 #include "runtime/deoptimization.hpp"
61 #include "runtime/escapeBarrier.hpp"
62 #include "runtime/fieldDescriptor.hpp"
63 #include "runtime/fieldDescriptor.inline.hpp"
64 #include "runtime/frame.inline.hpp"
65 #include "runtime/handles.inline.hpp"
66 #include "runtime/interfaceSupport.inline.hpp"
67 #include "runtime/jniHandles.inline.hpp"
68 #include "runtime/keepStackGCProcessed.hpp"
69 #include "runtime/objectMonitor.inline.hpp"
70 #include "runtime/osThread.hpp"
71 #include "runtime/safepointVerifiers.hpp"
72 #include "runtime/sharedRuntime.hpp"
73 #include "runtime/signature.hpp"
74 #include "runtime/stackFrameStream.inline.hpp"
75 #include "runtime/stackWatermarkSet.hpp"
76 #include "runtime/stubRoutines.hpp"
77 #include "runtime/thread.hpp"
78 #include "runtime/threadSMR.hpp"
79 #include "runtime/threadWXSetters.inline.hpp"
80 #include "runtime/vframe.hpp"
81 #include "runtime/vframeArray.hpp"
82 #include "runtime/vframe_hp.hpp"
83 #include "runtime/vmOperations.hpp"
84 #include "utilities/events.hpp"
85 #include "utilities/macros.hpp"
86 #include "utilities/preserveException.hpp"
87 #include "utilities/xmlstream.hpp"
88 #if INCLUDE_JFR
89 #include "jfr/jfrEvents.hpp"
90 #include "jfr/metadata/jfrSerializer.hpp"
91 #endif
92
93 bool DeoptimizationMarker::_is_active = false;
94
95 Deoptimization::UnrollBlock::UnrollBlock(int size_of_deoptimized_frame,
96 int caller_adjustment,
97 int caller_actual_parameters,
98 int number_of_frames,
99 intptr_t* frame_sizes,
100 address* frame_pcs,
101 BasicType return_type,
102 int exec_mode) {
103 _size_of_deoptimized_frame = size_of_deoptimized_frame;
104 _caller_adjustment = caller_adjustment;
105 _caller_actual_parameters = caller_actual_parameters;
106 _number_of_frames = number_of_frames;
107 _frame_sizes = frame_sizes;
108 _frame_pcs = frame_pcs;
109 _register_block = NEW_C_HEAP_ARRAY(intptr_t, RegisterMap::reg_count * 2, mtCompiler);
110 _return_type = return_type;
111 _initial_info = 0;
112 // PD (x86 only)
113 _counter_temp = 0;
114 _unpack_kind = exec_mode;
115 _sender_sp_temp = 0;
116
117 _total_frame_sizes = size_of_frames();
118 assert(exec_mode >= 0 && exec_mode < Unpack_LIMIT, "Unexpected exec_mode");
119 }
120
121
122 Deoptimization::UnrollBlock::~UnrollBlock() {
123 FREE_C_HEAP_ARRAY(intptr_t, _frame_sizes);
124 FREE_C_HEAP_ARRAY(intptr_t, _frame_pcs);
125 FREE_C_HEAP_ARRAY(intptr_t, _register_block);
126 }
127
128
129 intptr_t* Deoptimization::UnrollBlock::value_addr_at(int register_number) const {
130 assert(register_number < RegisterMap::reg_count, "checking register number");
131 return &_register_block[register_number * 2];
132 }
133
134
135
136 int Deoptimization::UnrollBlock::size_of_frames() const {
137 // Acount first for the adjustment of the initial frame
138 int result = _caller_adjustment;
139 for (int index = 0; index < number_of_frames(); index++) {
140 result += frame_sizes()[index];
141 }
142 return result;
143 }
144
145
146 void Deoptimization::UnrollBlock::print() {
147 ttyLocker ttyl;
148 tty->print_cr("UnrollBlock");
149 tty->print_cr(" size_of_deoptimized_frame = %d", _size_of_deoptimized_frame);
150 tty->print( " frame_sizes: ");
151 for (int index = 0; index < number_of_frames(); index++) {
152 tty->print(INTX_FORMAT " ", frame_sizes()[index]);
153 }
154 tty->cr();
155 }
156
157
158 // In order to make fetch_unroll_info work properly with escape
159 // analysis, the method was changed from JRT_LEAF to JRT_BLOCK_ENTRY.
160 // The actual reallocation of previously eliminated objects occurs in realloc_objects,
161 // which is called from the method fetch_unroll_info_helper below.
162 JRT_BLOCK_ENTRY(Deoptimization::UnrollBlock*, Deoptimization::fetch_unroll_info(JavaThread* current, int exec_mode))
163 // fetch_unroll_info() is called at the beginning of the deoptimization
164 // handler. Note this fact before we start generating temporary frames
165 // that can confuse an asynchronous stack walker. This counter is
166 // decremented at the end of unpack_frames().
167 if (TraceDeoptimization) {
168 tty->print_cr("Deoptimizing thread " INTPTR_FORMAT, p2i(current));
169 }
170 current->inc_in_deopt_handler();
171
172 if (exec_mode == Unpack_exception) {
173 // When we get here, a callee has thrown an exception into a deoptimized
174 // frame. That throw might have deferred stack watermark checking until
175 // after unwinding. So we deal with such deferred requests here.
176 StackWatermarkSet::after_unwind(current);
177 }
178
179 return fetch_unroll_info_helper(current, exec_mode);
180 JRT_END
181
182 #if COMPILER2_OR_JVMCI
183 static bool rematerialize_objects(JavaThread* thread, int exec_mode, CompiledMethod* compiled_method,
184 frame& deoptee, RegisterMap& map, GrowableArray<compiledVFrame*>* chunk,
185 bool& deoptimized_objects) {
186 bool realloc_failures = false;
187 assert (chunk->at(0)->scope() != NULL,"expect only compiled java frames");
188
189 JavaThread* deoptee_thread = chunk->at(0)->thread();
190 assert(exec_mode == Deoptimization::Unpack_none || (deoptee_thread == thread),
191 "a frame can only be deoptimized by the owner thread");
192
193 GrowableArray<ScopeValue*>* objects = chunk->at(0)->scope()->objects();
194
195 // The flag return_oop() indicates call sites which return oop
196 // in compiled code. Such sites include java method calls,
197 // runtime calls (for example, used to allocate new objects/arrays
198 // on slow code path) and any other calls generated in compiled code.
199 // It is not guaranteed that we can get such information here only
200 // by analyzing bytecode in deoptimized frames. This is why this flag
201 // is set during method compilation (see Compile::Process_OopMap_Node()).
202 // If the previous frame was popped or if we are dispatching an exception,
203 // we don't have an oop result.
204 bool save_oop_result = chunk->at(0)->scope()->return_oop() && !thread->popframe_forcing_deopt_reexecution() && (exec_mode == Deoptimization::Unpack_deopt);
205 Handle return_value;
206 if (save_oop_result) {
207 // Reallocation may trigger GC. If deoptimization happened on return from
208 // call which returns oop we need to save it since it is not in oopmap.
209 oop result = deoptee.saved_oop_result(&map);
210 assert(oopDesc::is_oop_or_null(result), "must be oop");
211 return_value = Handle(thread, result);
212 assert(Universe::heap()->is_in_or_null(result), "must be heap pointer");
213 if (TraceDeoptimization) {
214 ttyLocker ttyl;
215 tty->print_cr("SAVED OOP RESULT " INTPTR_FORMAT " in thread " INTPTR_FORMAT, p2i(result), p2i(thread));
216 }
217 }
218 if (objects != NULL) {
219 if (exec_mode == Deoptimization::Unpack_none) {
220 assert(thread->thread_state() == _thread_in_vm, "assumption");
221 JavaThread* THREAD = thread; // For exception macros.
222 // Clear pending OOM if reallocation fails and return true indicating allocation failure
223 realloc_failures = Deoptimization::realloc_objects(thread, &deoptee, &map, objects, CHECK_AND_CLEAR_(true));
224 deoptimized_objects = true;
225 } else {
226 JavaThread* current = thread; // For JRT_BLOCK
227 JRT_BLOCK
228 realloc_failures = Deoptimization::realloc_objects(thread, &deoptee, &map, objects, THREAD);
229 JRT_END
230 }
231 bool skip_internal = (compiled_method != NULL) && !compiled_method->is_compiled_by_jvmci();
232 Deoptimization::reassign_fields(&deoptee, &map, objects, realloc_failures, skip_internal);
233 #ifndef PRODUCT
234 if (TraceDeoptimization) {
235 ttyLocker ttyl;
236 tty->print_cr("REALLOC OBJECTS in thread " INTPTR_FORMAT, p2i(deoptee_thread));
237 Deoptimization::print_objects(objects, realloc_failures);
238 }
239 #endif
240 }
241 if (save_oop_result) {
242 // Restore result.
243 deoptee.set_saved_oop_result(&map, return_value());
244 }
245 return realloc_failures;
246 }
247
248 static void restore_eliminated_locks(JavaThread* thread, GrowableArray<compiledVFrame*>* chunk, bool realloc_failures,
249 frame& deoptee, int exec_mode, bool& deoptimized_objects) {
250 JavaThread* deoptee_thread = chunk->at(0)->thread();
251 assert(!EscapeBarrier::objs_are_deoptimized(deoptee_thread, deoptee.id()), "must relock just once");
252 assert(thread == Thread::current(), "should be");
253 HandleMark hm(thread);
254 #ifndef PRODUCT
255 bool first = true;
256 #endif
257 for (int i = 0; i < chunk->length(); i++) {
258 compiledVFrame* cvf = chunk->at(i);
259 assert (cvf->scope() != NULL,"expect only compiled java frames");
260 GrowableArray<MonitorInfo*>* monitors = cvf->monitors();
261 if (monitors->is_nonempty()) {
262 bool relocked = Deoptimization::relock_objects(thread, monitors, deoptee_thread, deoptee,
263 exec_mode, realloc_failures);
264 deoptimized_objects = deoptimized_objects || relocked;
265 #ifndef PRODUCT
266 if (PrintDeoptimizationDetails) {
267 ttyLocker ttyl;
268 for (int j = 0; j < monitors->length(); j++) {
269 MonitorInfo* mi = monitors->at(j);
270 if (mi->eliminated()) {
271 if (first) {
272 first = false;
273 tty->print_cr("RELOCK OBJECTS in thread " INTPTR_FORMAT, p2i(thread));
274 }
275 if (exec_mode == Deoptimization::Unpack_none) {
276 ObjectMonitor* monitor = deoptee_thread->current_waiting_monitor();
277 if (monitor != NULL && monitor->object() == mi->owner()) {
278 tty->print_cr(" object <" INTPTR_FORMAT "> DEFERRED relocking after wait", p2i(mi->owner()));
279 continue;
280 }
281 }
282 if (mi->owner_is_scalar_replaced()) {
283 Klass* k = java_lang_Class::as_Klass(mi->owner_klass());
284 tty->print_cr(" failed reallocation for klass %s", k->external_name());
285 } else {
286 tty->print_cr(" object <" INTPTR_FORMAT "> locked", p2i(mi->owner()));
287 }
288 }
289 }
290 }
291 #endif // !PRODUCT
292 }
293 }
294 }
295
296 // Deoptimize objects, that is reallocate and relock them, just before they escape through JVMTI.
297 // The given vframes cover one physical frame.
298 bool Deoptimization::deoptimize_objects_internal(JavaThread* thread, GrowableArray<compiledVFrame*>* chunk,
299 bool& realloc_failures) {
300 frame deoptee = chunk->at(0)->fr();
301 JavaThread* deoptee_thread = chunk->at(0)->thread();
302 CompiledMethod* cm = deoptee.cb()->as_compiled_method_or_null();
303 RegisterMap map(chunk->at(0)->register_map());
304 bool deoptimized_objects = false;
305
306 bool const jvmci_enabled = JVMCI_ONLY(UseJVMCICompiler) NOT_JVMCI(false);
307
308 // Reallocate the non-escaping objects and restore their fields.
309 if (jvmci_enabled COMPILER2_PRESENT(|| (DoEscapeAnalysis && EliminateAllocations)
310 || EliminateAutoBox || EnableVectorAggressiveReboxing)) {
311 realloc_failures = rematerialize_objects(thread, Unpack_none, cm, deoptee, map, chunk, deoptimized_objects);
312 }
313
314 // Revoke biases of objects with eliminated locks in the given frame.
315 Deoptimization::revoke_for_object_deoptimization(deoptee_thread, deoptee, &map, thread);
316
317 // MonitorInfo structures used in eliminate_locks are not GC safe.
318 NoSafepointVerifier no_safepoint;
319
320 // Now relock objects if synchronization on them was eliminated.
321 if (jvmci_enabled COMPILER2_PRESENT(|| ((DoEscapeAnalysis || EliminateNestedLocks) && EliminateLocks))) {
322 restore_eliminated_locks(thread, chunk, realloc_failures, deoptee, Unpack_none, deoptimized_objects);
323 }
324 return deoptimized_objects;
325 }
326 #endif // COMPILER2_OR_JVMCI
327
328 // This is factored, since it is both called from a JRT_LEAF (deoptimization) and a JRT_ENTRY (uncommon_trap)
329 Deoptimization::UnrollBlock* Deoptimization::fetch_unroll_info_helper(JavaThread* current, int exec_mode) {
330 // When we get here we are about to unwind the deoptee frame. In order to
331 // catch not yet safe to use frames, the following stack watermark barrier
332 // poll will make such frames safe to use.
333 StackWatermarkSet::before_unwind(current);
334
335 // Note: there is a safepoint safety issue here. No matter whether we enter
336 // via vanilla deopt or uncommon trap we MUST NOT stop at a safepoint once
337 // the vframeArray is created.
338 //
339
340 // Allocate our special deoptimization ResourceMark
341 DeoptResourceMark* dmark = new DeoptResourceMark(current);
342 assert(current->deopt_mark() == NULL, "Pending deopt!");
343 current->set_deopt_mark(dmark);
344
345 frame stub_frame = current->last_frame(); // Makes stack walkable as side effect
346 RegisterMap map(current, true);
347 RegisterMap dummy_map(current, false);
348 // Now get the deoptee with a valid map
349 frame deoptee = stub_frame.sender(&map);
350 // Set the deoptee nmethod
351 assert(current->deopt_compiled_method() == NULL, "Pending deopt!");
352 CompiledMethod* cm = deoptee.cb()->as_compiled_method_or_null();
353 current->set_deopt_compiled_method(cm);
354
355 if (VerifyStack) {
356 current->validate_frame_layout();
357 }
358
359 // Create a growable array of VFrames where each VFrame represents an inlined
360 // Java frame. This storage is allocated with the usual system arena.
361 assert(deoptee.is_compiled_frame(), "Wrong frame type");
362 GrowableArray<compiledVFrame*>* chunk = new GrowableArray<compiledVFrame*>(10);
363 vframe* vf = vframe::new_vframe(&deoptee, &map, current);
364 while (!vf->is_top()) {
365 assert(vf->is_compiled_frame(), "Wrong frame type");
366 chunk->push(compiledVFrame::cast(vf));
367 vf = vf->sender();
368 }
369 assert(vf->is_compiled_frame(), "Wrong frame type");
370 chunk->push(compiledVFrame::cast(vf));
371
372 bool realloc_failures = false;
373
374 #if COMPILER2_OR_JVMCI
375 bool const jvmci_enabled = JVMCI_ONLY(EnableJVMCI) NOT_JVMCI(false);
376
377 // Reallocate the non-escaping objects and restore their fields. Then
378 // relock objects if synchronization on them was eliminated.
379 if (jvmci_enabled COMPILER2_PRESENT( || (DoEscapeAnalysis && EliminateAllocations)
380 || EliminateAutoBox || EnableVectorAggressiveReboxing )) {
381 bool unused;
382 realloc_failures = rematerialize_objects(current, exec_mode, cm, deoptee, map, chunk, unused);
383 }
384 #endif // COMPILER2_OR_JVMCI
385
386 // Revoke biases, done with in java state.
387 // No safepoints allowed after this
388 revoke_from_deopt_handler(current, deoptee, &map);
389
390 // Ensure that no safepoint is taken after pointers have been stored
391 // in fields of rematerialized objects. If a safepoint occurs from here on
392 // out the java state residing in the vframeArray will be missed.
393 // Locks may be rebaised in a safepoint.
394 NoSafepointVerifier no_safepoint;
395
396 #if COMPILER2_OR_JVMCI
397 if ((jvmci_enabled COMPILER2_PRESENT( || ((DoEscapeAnalysis || EliminateNestedLocks) && EliminateLocks) ))
398 && !EscapeBarrier::objs_are_deoptimized(current, deoptee.id())) {
399 bool unused;
400 restore_eliminated_locks(current, chunk, realloc_failures, deoptee, exec_mode, unused);
401 }
402 #endif // COMPILER2_OR_JVMCI
403
404 ScopeDesc* trap_scope = chunk->at(0)->scope();
405 Handle exceptionObject;
406 if (trap_scope->rethrow_exception()) {
407 if (PrintDeoptimizationDetails) {
408 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());
409 }
410 GrowableArray<ScopeValue*>* expressions = trap_scope->expressions();
411 guarantee(expressions != NULL && expressions->length() > 0, "must have exception to throw");
412 ScopeValue* topOfStack = expressions->top();
413 exceptionObject = StackValue::create_stack_value(&deoptee, &map, topOfStack)->get_obj();
414 guarantee(exceptionObject() != NULL, "exception oop can not be null");
415 }
416
417 vframeArray* array = create_vframeArray(current, deoptee, &map, chunk, realloc_failures);
418 #if COMPILER2_OR_JVMCI
419 if (realloc_failures) {
420 pop_frames_failed_reallocs(current, array);
421 }
422 #endif
423
424 assert(current->vframe_array_head() == NULL, "Pending deopt!");
425 current->set_vframe_array_head(array);
426
427 // Now that the vframeArray has been created if we have any deferred local writes
428 // added by jvmti then we can free up that structure as the data is now in the
429 // vframeArray
430
431 JvmtiDeferredUpdates::delete_updates_for_frame(current, array->original().id());
432
433 // Compute the caller frame based on the sender sp of stub_frame and stored frame sizes info.
434 CodeBlob* cb = stub_frame.cb();
435 // Verify we have the right vframeArray
436 assert(cb->frame_size() >= 0, "Unexpected frame size");
437 intptr_t* unpack_sp = stub_frame.sp() + cb->frame_size();
438
439 // If the deopt call site is a MethodHandle invoke call site we have
440 // to adjust the unpack_sp.
441 nmethod* deoptee_nm = deoptee.cb()->as_nmethod_or_null();
442 if (deoptee_nm != NULL && deoptee_nm->is_method_handle_return(deoptee.pc()))
443 unpack_sp = deoptee.unextended_sp();
444
445 #ifdef ASSERT
446 assert(cb->is_deoptimization_stub() ||
447 cb->is_uncommon_trap_stub() ||
448 strcmp("Stub<DeoptimizationStub.deoptimizationHandler>", cb->name()) == 0 ||
449 strcmp("Stub<UncommonTrapStub.uncommonTrapHandler>", cb->name()) == 0,
450 "unexpected code blob: %s", cb->name());
451 #endif
452
453 // This is a guarantee instead of an assert because if vframe doesn't match
454 // we will unpack the wrong deoptimized frame and wind up in strange places
455 // where it will be very difficult to figure out what went wrong. Better
456 // to die an early death here than some very obscure death later when the
457 // trail is cold.
458 // Note: on ia64 this guarantee can be fooled by frames with no memory stack
459 // in that it will fail to detect a problem when there is one. This needs
460 // more work in tiger timeframe.
461 guarantee(array->unextended_sp() == unpack_sp, "vframe_array_head must contain the vframeArray to unpack");
462
463 int number_of_frames = array->frames();
464
465 // Compute the vframes' sizes. Note that frame_sizes[] entries are ordered from outermost to innermost
466 // virtual activation, which is the reverse of the elements in the vframes array.
467 intptr_t* frame_sizes = NEW_C_HEAP_ARRAY(intptr_t, number_of_frames, mtCompiler);
468 // +1 because we always have an interpreter return address for the final slot.
469 address* frame_pcs = NEW_C_HEAP_ARRAY(address, number_of_frames + 1, mtCompiler);
470 int popframe_extra_args = 0;
471 // Create an interpreter return address for the stub to use as its return
472 // address so the skeletal frames are perfectly walkable
473 frame_pcs[number_of_frames] = Interpreter::deopt_entry(vtos, 0);
474
475 // PopFrame requires that the preserved incoming arguments from the recently-popped topmost
476 // activation be put back on the expression stack of the caller for reexecution
477 if (JvmtiExport::can_pop_frame() && current->popframe_forcing_deopt_reexecution()) {
478 popframe_extra_args = in_words(current->popframe_preserved_args_size_in_words());
479 }
480
481 // Find the current pc for sender of the deoptee. Since the sender may have been deoptimized
482 // itself since the deoptee vframeArray was created we must get a fresh value of the pc rather
483 // than simply use array->sender.pc(). This requires us to walk the current set of frames
484 //
485 frame deopt_sender = stub_frame.sender(&dummy_map); // First is the deoptee frame
486 deopt_sender = deopt_sender.sender(&dummy_map); // Now deoptee caller
487
488 // It's possible that the number of parameters at the call site is
489 // different than number of arguments in the callee when method
490 // handles are used. If the caller is interpreted get the real
491 // value so that the proper amount of space can be added to it's
492 // frame.
493 bool caller_was_method_handle = false;
494 if (deopt_sender.is_interpreted_frame()) {
495 methodHandle method(current, deopt_sender.interpreter_frame_method());
496 Bytecode_invoke cur = Bytecode_invoke_check(method, deopt_sender.interpreter_frame_bci());
497 if (cur.is_invokedynamic() || cur.is_invokehandle()) {
498 // Method handle invokes may involve fairly arbitrary chains of
499 // calls so it's impossible to know how much actual space the
500 // caller has for locals.
501 caller_was_method_handle = true;
502 }
503 }
504
505 //
506 // frame_sizes/frame_pcs[0] oldest frame (int or c2i)
507 // frame_sizes/frame_pcs[1] next oldest frame (int)
508 // frame_sizes/frame_pcs[n] youngest frame (int)
509 //
510 // Now a pc in frame_pcs is actually the return address to the frame's caller (a frame
511 // owns the space for the return address to it's caller). Confusing ain't it.
512 //
513 // The vframe array can address vframes with indices running from
514 // 0.._frames-1. Index 0 is the youngest frame and _frame - 1 is the oldest (root) frame.
515 // When we create the skeletal frames we need the oldest frame to be in the zero slot
516 // in the frame_sizes/frame_pcs so the assembly code can do a trivial walk.
517 // so things look a little strange in this loop.
518 //
519 int callee_parameters = 0;
520 int callee_locals = 0;
521 for (int index = 0; index < array->frames(); index++ ) {
522 // frame[number_of_frames - 1 ] = on_stack_size(youngest)
523 // frame[number_of_frames - 2 ] = on_stack_size(sender(youngest))
524 // frame[number_of_frames - 3 ] = on_stack_size(sender(sender(youngest)))
525 frame_sizes[number_of_frames - 1 - index] = BytesPerWord * array->element(index)->on_stack_size(callee_parameters,
526 callee_locals,
527 index == 0,
528 popframe_extra_args);
529 // This pc doesn't have to be perfect just good enough to identify the frame
530 // as interpreted so the skeleton frame will be walkable
531 // The correct pc will be set when the skeleton frame is completely filled out
532 // The final pc we store in the loop is wrong and will be overwritten below
533 frame_pcs[number_of_frames - 1 - index ] = Interpreter::deopt_entry(vtos, 0) - frame::pc_return_offset;
534
535 callee_parameters = array->element(index)->method()->size_of_parameters();
536 callee_locals = array->element(index)->method()->max_locals();
537 popframe_extra_args = 0;
538 }
539
540 // Compute whether the root vframe returns a float or double value.
541 BasicType return_type;
542 {
543 methodHandle method(current, array->element(0)->method());
544 Bytecode_invoke invoke = Bytecode_invoke_check(method, array->element(0)->bci());
545 return_type = invoke.is_valid() ? invoke.result_type() : T_ILLEGAL;
546 }
547
548 // Compute information for handling adapters and adjusting the frame size of the caller.
549 int caller_adjustment = 0;
550
551 // Compute the amount the oldest interpreter frame will have to adjust
552 // its caller's stack by. If the caller is a compiled frame then
553 // we pretend that the callee has no parameters so that the
554 // extension counts for the full amount of locals and not just
555 // locals-parms. This is because without a c2i adapter the parm
556 // area as created by the compiled frame will not be usable by
557 // the interpreter. (Depending on the calling convention there
558 // may not even be enough space).
559
560 // QQQ I'd rather see this pushed down into last_frame_adjust
561 // and have it take the sender (aka caller).
562
563 if (deopt_sender.is_compiled_frame() || caller_was_method_handle) {
564 caller_adjustment = last_frame_adjust(0, callee_locals);
565 } else if (callee_locals > callee_parameters) {
566 // The caller frame may need extending to accommodate
567 // non-parameter locals of the first unpacked interpreted frame.
568 // Compute that adjustment.
569 caller_adjustment = last_frame_adjust(callee_parameters, callee_locals);
570 }
571
572 // If the sender is deoptimized the we must retrieve the address of the handler
573 // since the frame will "magically" show the original pc before the deopt
574 // and we'd undo the deopt.
575
576 frame_pcs[0] = deopt_sender.raw_pc();
577
578 assert(CodeCache::find_blob_unsafe(frame_pcs[0]) != NULL, "bad pc");
579
580 #if INCLUDE_JVMCI
581 if (exceptionObject() != NULL) {
582 current->set_exception_oop(exceptionObject());
583 exec_mode = Unpack_exception;
584 }
585 #endif
586
587 if (current->frames_to_pop_failed_realloc() > 0 && exec_mode != Unpack_uncommon_trap) {
588 assert(current->has_pending_exception(), "should have thrown OOME");
589 current->set_exception_oop(current->pending_exception());
590 current->clear_pending_exception();
591 exec_mode = Unpack_exception;
592 }
593
594 #if INCLUDE_JVMCI
595 if (current->frames_to_pop_failed_realloc() > 0) {
596 current->set_pending_monitorenter(false);
597 }
598 #endif
599
600 UnrollBlock* info = new UnrollBlock(array->frame_size() * BytesPerWord,
601 caller_adjustment * BytesPerWord,
602 caller_was_method_handle ? 0 : callee_parameters,
603 number_of_frames,
604 frame_sizes,
605 frame_pcs,
606 return_type,
607 exec_mode);
608 // On some platforms, we need a way to pass some platform dependent
609 // information to the unpacking code so the skeletal frames come out
610 // correct (initial fp value, unextended sp, ...)
611 info->set_initial_info((intptr_t) array->sender().initial_deoptimization_info());
612
613 if (array->frames() > 1) {
614 if (VerifyStack && TraceDeoptimization) {
615 ttyLocker ttyl;
616 tty->print_cr("Deoptimizing method containing inlining");
617 }
618 }
619
620 array->set_unroll_block(info);
621 return info;
622 }
623
624 // Called to cleanup deoptimization data structures in normal case
625 // after unpacking to stack and when stack overflow error occurs
626 void Deoptimization::cleanup_deopt_info(JavaThread *thread,
627 vframeArray *array) {
628
629 // Get array if coming from exception
630 if (array == NULL) {
631 array = thread->vframe_array_head();
632 }
633 thread->set_vframe_array_head(NULL);
634
635 // Free the previous UnrollBlock
636 vframeArray* old_array = thread->vframe_array_last();
637 thread->set_vframe_array_last(array);
638
639 if (old_array != NULL) {
640 UnrollBlock* old_info = old_array->unroll_block();
641 old_array->set_unroll_block(NULL);
642 delete old_info;
643 delete old_array;
644 }
645
646 // Deallocate any resource creating in this routine and any ResourceObjs allocated
647 // inside the vframeArray (StackValueCollections)
648
649 delete thread->deopt_mark();
650 thread->set_deopt_mark(NULL);
651 thread->set_deopt_compiled_method(NULL);
652
653
654 if (JvmtiExport::can_pop_frame()) {
655 // Regardless of whether we entered this routine with the pending
656 // popframe condition bit set, we should always clear it now
657 thread->clear_popframe_condition();
658 }
659
660 // unpack_frames() is called at the end of the deoptimization handler
661 // and (in C2) at the end of the uncommon trap handler. Note this fact
662 // so that an asynchronous stack walker can work again. This counter is
663 // incremented at the beginning of fetch_unroll_info() and (in C2) at
664 // the beginning of uncommon_trap().
665 thread->dec_in_deopt_handler();
666 }
667
668 // Moved from cpu directories because none of the cpus has callee save values.
669 // If a cpu implements callee save values, move this to deoptimization_<cpu>.cpp.
670 void Deoptimization::unwind_callee_save_values(frame* f, vframeArray* vframe_array) {
671
672 // This code is sort of the equivalent of C2IAdapter::setup_stack_frame back in
673 // the days we had adapter frames. When we deoptimize a situation where a
674 // compiled caller calls a compiled caller will have registers it expects
675 // to survive the call to the callee. If we deoptimize the callee the only
676 // way we can restore these registers is to have the oldest interpreter
677 // frame that we create restore these values. That is what this routine
678 // will accomplish.
679
680 // At the moment we have modified c2 to not have any callee save registers
681 // so this problem does not exist and this routine is just a place holder.
682
683 assert(f->is_interpreted_frame(), "must be interpreted");
684 }
685
686 #ifndef PRODUCT
687 static bool falls_through(Bytecodes::Code bc) {
688 switch (bc) {
689 // List may be incomplete. Here we really only care about bytecodes where compiled code
690 // can deoptimize.
691 case Bytecodes::_goto:
692 case Bytecodes::_goto_w:
693 case Bytecodes::_athrow:
694 return false;
695 default:
696 return true;
697 }
698 }
699 #endif
700
701 // Return BasicType of value being returned
702 JRT_LEAF(BasicType, Deoptimization::unpack_frames(JavaThread* thread, int exec_mode))
703
704 // We are already active in the special DeoptResourceMark any ResourceObj's we
705 // allocate will be freed at the end of the routine.
706
707 // JRT_LEAF methods don't normally allocate handles and there is a
708 // NoHandleMark to enforce that. It is actually safe to use Handles
709 // in a JRT_LEAF method, and sometimes desirable, but to do so we
710 // must use ResetNoHandleMark to bypass the NoHandleMark, and
711 // then use a HandleMark to ensure any Handles we do create are
712 // cleaned up in this scope.
713 ResetNoHandleMark rnhm;
714 HandleMark hm(thread);
715
716 frame stub_frame = thread->last_frame();
717
718 // Since the frame to unpack is the top frame of this thread, the vframe_array_head
719 // must point to the vframeArray for the unpack frame.
720 vframeArray* array = thread->vframe_array_head();
721
722 #ifndef PRODUCT
723 if (TraceDeoptimization) {
724 ttyLocker ttyl;
725 tty->print_cr("DEOPT UNPACKING thread " INTPTR_FORMAT " vframeArray " INTPTR_FORMAT " mode %d",
726 p2i(thread), p2i(array), exec_mode);
727 }
728 #endif
729 Events::log_deopt_message(thread, "DEOPT UNPACKING pc=" INTPTR_FORMAT " sp=" INTPTR_FORMAT " mode %d",
730 p2i(stub_frame.pc()), p2i(stub_frame.sp()), exec_mode);
731
732 UnrollBlock* info = array->unroll_block();
733
734 // We set the last_Java frame. But the stack isn't really parsable here. So we
735 // clear it to make sure JFR understands not to try and walk stacks from events
736 // in here.
737 intptr_t* sp = thread->frame_anchor()->last_Java_sp();
738 thread->frame_anchor()->set_last_Java_sp(NULL);
739
740 // Unpack the interpreter frames and any adapter frame (c2 only) we might create.
741 array->unpack_to_stack(stub_frame, exec_mode, info->caller_actual_parameters());
742
743 thread->frame_anchor()->set_last_Java_sp(sp);
744
745 BasicType bt = info->return_type();
746
747 // If we have an exception pending, claim that the return type is an oop
748 // so the deopt_blob does not overwrite the exception_oop.
749
750 if (exec_mode == Unpack_exception)
751 bt = T_OBJECT;
752
753 // Cleanup thread deopt data
754 cleanup_deopt_info(thread, array);
755
756 #ifndef PRODUCT
757 if (VerifyStack) {
758 ResourceMark res_mark;
759 // Clear pending exception to not break verification code (restored afterwards)
760 PreserveExceptionMark pm(thread);
761
762 thread->validate_frame_layout();
763
764 // Verify that the just-unpacked frames match the interpreter's
765 // notions of expression stack and locals
766 vframeArray* cur_array = thread->vframe_array_last();
767 RegisterMap rm(thread, false);
768 rm.set_include_argument_oops(false);
769 bool is_top_frame = true;
770 int callee_size_of_parameters = 0;
771 int callee_max_locals = 0;
772 for (int i = 0; i < cur_array->frames(); i++) {
773 vframeArrayElement* el = cur_array->element(i);
774 frame* iframe = el->iframe();
775 guarantee(iframe->is_interpreted_frame(), "Wrong frame type");
776
777 // Get the oop map for this bci
778 InterpreterOopMap mask;
779 int cur_invoke_parameter_size = 0;
780 bool try_next_mask = false;
781 int next_mask_expression_stack_size = -1;
782 int top_frame_expression_stack_adjustment = 0;
783 methodHandle mh(thread, iframe->interpreter_frame_method());
784 OopMapCache::compute_one_oop_map(mh, iframe->interpreter_frame_bci(), &mask);
785 BytecodeStream str(mh, iframe->interpreter_frame_bci());
786 int max_bci = mh->code_size();
787 // Get to the next bytecode if possible
788 assert(str.bci() < max_bci, "bci in interpreter frame out of bounds");
789 // Check to see if we can grab the number of outgoing arguments
790 // at an uncommon trap for an invoke (where the compiler
791 // generates debug info before the invoke has executed)
792 Bytecodes::Code cur_code = str.next();
793 Bytecodes::Code next_code = Bytecodes::_shouldnotreachhere;
794 if (Bytecodes::is_invoke(cur_code)) {
795 Bytecode_invoke invoke(mh, iframe->interpreter_frame_bci());
796 cur_invoke_parameter_size = invoke.size_of_parameters();
797 if (i != 0 && !invoke.is_invokedynamic() && MethodHandles::has_member_arg(invoke.klass(), invoke.name())) {
798 callee_size_of_parameters++;
799 }
800 }
801 if (str.bci() < max_bci) {
802 next_code = str.next();
803 if (next_code >= 0) {
804 // The interpreter oop map generator reports results before
805 // the current bytecode has executed except in the case of
806 // calls. It seems to be hard to tell whether the compiler
807 // has emitted debug information matching the "state before"
808 // a given bytecode or the state after, so we try both
809 if (!Bytecodes::is_invoke(cur_code) && falls_through(cur_code)) {
810 // Get expression stack size for the next bytecode
811 InterpreterOopMap next_mask;
812 OopMapCache::compute_one_oop_map(mh, str.bci(), &next_mask);
813 next_mask_expression_stack_size = next_mask.expression_stack_size();
814 if (Bytecodes::is_invoke(next_code)) {
815 Bytecode_invoke invoke(mh, str.bci());
816 next_mask_expression_stack_size += invoke.size_of_parameters();
817 }
818 // Need to subtract off the size of the result type of
819 // the bytecode because this is not described in the
820 // debug info but returned to the interpreter in the TOS
821 // caching register
822 BasicType bytecode_result_type = Bytecodes::result_type(cur_code);
823 if (bytecode_result_type != T_ILLEGAL) {
824 top_frame_expression_stack_adjustment = type2size[bytecode_result_type];
825 }
826 assert(top_frame_expression_stack_adjustment >= 0, "stack adjustment must be positive");
827 try_next_mask = true;
828 }
829 }
830 }
831
832 // Verify stack depth and oops in frame
833 // This assertion may be dependent on the platform we're running on and may need modification (tested on x86 and sparc)
834 if (!(
835 /* SPARC */
836 (iframe->interpreter_frame_expression_stack_size() == mask.expression_stack_size() + callee_size_of_parameters) ||
837 /* x86 */
838 (iframe->interpreter_frame_expression_stack_size() == mask.expression_stack_size() + callee_max_locals) ||
839 (try_next_mask &&
840 (iframe->interpreter_frame_expression_stack_size() == (next_mask_expression_stack_size -
841 top_frame_expression_stack_adjustment))) ||
842 (is_top_frame && (exec_mode == Unpack_exception) && iframe->interpreter_frame_expression_stack_size() == 0) ||
843 (is_top_frame && (exec_mode == Unpack_uncommon_trap || exec_mode == Unpack_reexecute || el->should_reexecute()) &&
844 (iframe->interpreter_frame_expression_stack_size() == mask.expression_stack_size() + cur_invoke_parameter_size))
845 )) {
846 {
847 ttyLocker ttyl;
848
849 // Print out some information that will help us debug the problem
850 tty->print_cr("Wrong number of expression stack elements during deoptimization");
851 tty->print_cr(" Error occurred while verifying frame %d (0..%d, 0 is topmost)", i, cur_array->frames() - 1);
852 tty->print_cr(" Current code %s", Bytecodes::name(cur_code));
853 if (try_next_mask) {
854 tty->print_cr(" Next code %s", Bytecodes::name(next_code));
855 }
856 tty->print_cr(" Fabricated interpreter frame had %d expression stack elements",
857 iframe->interpreter_frame_expression_stack_size());
858 tty->print_cr(" Interpreter oop map had %d expression stack elements", mask.expression_stack_size());
859 tty->print_cr(" try_next_mask = %d", try_next_mask);
860 tty->print_cr(" next_mask_expression_stack_size = %d", next_mask_expression_stack_size);
861 tty->print_cr(" callee_size_of_parameters = %d", callee_size_of_parameters);
862 tty->print_cr(" callee_max_locals = %d", callee_max_locals);
863 tty->print_cr(" top_frame_expression_stack_adjustment = %d", top_frame_expression_stack_adjustment);
864 tty->print_cr(" exec_mode = %d", exec_mode);
865 tty->print_cr(" cur_invoke_parameter_size = %d", cur_invoke_parameter_size);
866 tty->print_cr(" Thread = " INTPTR_FORMAT ", thread ID = %d", p2i(thread), thread->osthread()->thread_id());
867 tty->print_cr(" Interpreted frames:");
868 for (int k = 0; k < cur_array->frames(); k++) {
869 vframeArrayElement* el = cur_array->element(k);
870 tty->print_cr(" %s (bci %d)", el->method()->name_and_sig_as_C_string(), el->bci());
871 }
872 cur_array->print_on_2(tty);
873 } // release tty lock before calling guarantee
874 guarantee(false, "wrong number of expression stack elements during deopt");
875 }
876 VerifyOopClosure verify;
877 iframe->oops_interpreted_do(&verify, &rm, false);
878 callee_size_of_parameters = mh->size_of_parameters();
879 callee_max_locals = mh->max_locals();
880 is_top_frame = false;
881 }
882 }
883 #endif /* !PRODUCT */
884
885 return bt;
886 JRT_END
887
888 class DeoptimizeMarkedClosure : public HandshakeClosure {
889 public:
890 DeoptimizeMarkedClosure() : HandshakeClosure("Deoptimize") {}
891 void do_thread(Thread* thread) {
892 JavaThread* jt = thread->as_Java_thread();
893 jt->deoptimize_marked_methods();
894 }
895 };
896
897 void Deoptimization::deoptimize_all_marked(nmethod* nmethod_only) {
898 ResourceMark rm;
899 DeoptimizationMarker dm;
900
901 // Make the dependent methods not entrant
902 if (nmethod_only != NULL) {
903 nmethod_only->mark_for_deoptimization();
904 nmethod_only->make_not_entrant();
905 } else {
906 MutexLocker mu(SafepointSynchronize::is_at_safepoint() ? NULL : CodeCache_lock, Mutex::_no_safepoint_check_flag);
907 CodeCache::make_marked_nmethods_not_entrant();
908 }
909
910 DeoptimizeMarkedClosure deopt;
911 if (SafepointSynchronize::is_at_safepoint()) {
912 Threads::java_threads_do(&deopt);
913 } else {
914 Handshake::execute(&deopt);
915 }
916 }
917
918 Deoptimization::DeoptAction Deoptimization::_unloaded_action
919 = Deoptimization::Action_reinterpret;
920
921 #if COMPILER2_OR_JVMCI
922 template<typename CacheType>
923 class BoxCacheBase : public CHeapObj<mtCompiler> {
924 protected:
925 static InstanceKlass* find_cache_klass(Symbol* klass_name) {
926 ResourceMark rm;
927 char* klass_name_str = klass_name->as_C_string();
928 InstanceKlass* ik = SystemDictionary::find_instance_klass(klass_name, Handle(), Handle());
929 guarantee(ik != NULL, "%s must be loaded", klass_name_str);
930 guarantee(ik->is_initialized(), "%s must be initialized", klass_name_str);
931 CacheType::compute_offsets(ik);
932 return ik;
933 }
934 };
935
936 template<typename PrimitiveType, typename CacheType, typename BoxType> class BoxCache : public BoxCacheBase<CacheType> {
937 PrimitiveType _low;
938 PrimitiveType _high;
939 jobject _cache;
940 protected:
941 static BoxCache<PrimitiveType, CacheType, BoxType> *_singleton;
942 BoxCache(Thread* thread) {
943 InstanceKlass* ik = BoxCacheBase<CacheType>::find_cache_klass(CacheType::symbol());
944 objArrayOop cache = CacheType::cache(ik);
945 assert(cache->length() > 0, "Empty cache");
946 _low = BoxType::value(cache->obj_at(0));
947 _high = _low + cache->length() - 1;
948 _cache = JNIHandles::make_global(Handle(thread, cache));
949 }
950 ~BoxCache() {
951 JNIHandles::destroy_global(_cache);
952 }
953 public:
954 static BoxCache<PrimitiveType, CacheType, BoxType>* singleton(Thread* thread) {
955 if (_singleton == NULL) {
956 BoxCache<PrimitiveType, CacheType, BoxType>* s = new BoxCache<PrimitiveType, CacheType, BoxType>(thread);
957 if (!Atomic::replace_if_null(&_singleton, s)) {
958 delete s;
959 }
960 }
961 return _singleton;
962 }
963 oop lookup(PrimitiveType value) {
964 if (_low <= value && value <= _high) {
965 int offset = value - _low;
966 return objArrayOop(JNIHandles::resolve_non_null(_cache))->obj_at(offset);
967 }
968 return NULL;
969 }
970 oop lookup_raw(intptr_t raw_value) {
971 // Have to cast to avoid little/big-endian problems.
972 if (sizeof(PrimitiveType) > sizeof(jint)) {
973 jlong value = (jlong)raw_value;
974 return lookup(value);
975 }
976 PrimitiveType value = (PrimitiveType)*((jint*)&raw_value);
977 return lookup(value);
978 }
979 };
980
981 typedef BoxCache<jint, java_lang_Integer_IntegerCache, java_lang_Integer> IntegerBoxCache;
982 typedef BoxCache<jlong, java_lang_Long_LongCache, java_lang_Long> LongBoxCache;
983 typedef BoxCache<jchar, java_lang_Character_CharacterCache, java_lang_Character> CharacterBoxCache;
984 typedef BoxCache<jshort, java_lang_Short_ShortCache, java_lang_Short> ShortBoxCache;
985 typedef BoxCache<jbyte, java_lang_Byte_ByteCache, java_lang_Byte> ByteBoxCache;
986
987 template<> BoxCache<jint, java_lang_Integer_IntegerCache, java_lang_Integer>* BoxCache<jint, java_lang_Integer_IntegerCache, java_lang_Integer>::_singleton = NULL;
988 template<> BoxCache<jlong, java_lang_Long_LongCache, java_lang_Long>* BoxCache<jlong, java_lang_Long_LongCache, java_lang_Long>::_singleton = NULL;
989 template<> BoxCache<jchar, java_lang_Character_CharacterCache, java_lang_Character>* BoxCache<jchar, java_lang_Character_CharacterCache, java_lang_Character>::_singleton = NULL;
990 template<> BoxCache<jshort, java_lang_Short_ShortCache, java_lang_Short>* BoxCache<jshort, java_lang_Short_ShortCache, java_lang_Short>::_singleton = NULL;
991 template<> BoxCache<jbyte, java_lang_Byte_ByteCache, java_lang_Byte>* BoxCache<jbyte, java_lang_Byte_ByteCache, java_lang_Byte>::_singleton = NULL;
992
993 class BooleanBoxCache : public BoxCacheBase<java_lang_Boolean> {
994 jobject _true_cache;
995 jobject _false_cache;
996 protected:
997 static BooleanBoxCache *_singleton;
998 BooleanBoxCache(Thread *thread) {
999 InstanceKlass* ik = find_cache_klass(java_lang_Boolean::symbol());
1000 _true_cache = JNIHandles::make_global(Handle(thread, java_lang_Boolean::get_TRUE(ik)));
1001 _false_cache = JNIHandles::make_global(Handle(thread, java_lang_Boolean::get_FALSE(ik)));
1002 }
1003 ~BooleanBoxCache() {
1004 JNIHandles::destroy_global(_true_cache);
1005 JNIHandles::destroy_global(_false_cache);
1006 }
1007 public:
1008 static BooleanBoxCache* singleton(Thread* thread) {
1009 if (_singleton == NULL) {
1010 BooleanBoxCache* s = new BooleanBoxCache(thread);
1011 if (!Atomic::replace_if_null(&_singleton, s)) {
1012 delete s;
1013 }
1014 }
1015 return _singleton;
1016 }
1017 oop lookup_raw(intptr_t raw_value) {
1018 // Have to cast to avoid little/big-endian problems.
1019 jboolean value = (jboolean)*((jint*)&raw_value);
1020 return lookup(value);
1021 }
1022 oop lookup(jboolean value) {
1023 if (value != 0) {
1024 return JNIHandles::resolve_non_null(_true_cache);
1025 }
1026 return JNIHandles::resolve_non_null(_false_cache);
1027 }
1028 };
1029
1030 BooleanBoxCache* BooleanBoxCache::_singleton = NULL;
1031
1032 oop Deoptimization::get_cached_box(AutoBoxObjectValue* bv, frame* fr, RegisterMap* reg_map, TRAPS) {
1033 Klass* k = java_lang_Class::as_Klass(bv->klass()->as_ConstantOopReadValue()->value()());
1034 BasicType box_type = vmClasses::box_klass_type(k);
1035 if (box_type != T_OBJECT) {
1036 StackValue* value = StackValue::create_stack_value(fr, reg_map, bv->field_at(box_type == T_LONG ? 1 : 0));
1037 switch(box_type) {
1038 case T_INT: return IntegerBoxCache::singleton(THREAD)->lookup_raw(value->get_int());
1039 case T_CHAR: return CharacterBoxCache::singleton(THREAD)->lookup_raw(value->get_int());
1040 case T_SHORT: return ShortBoxCache::singleton(THREAD)->lookup_raw(value->get_int());
1041 case T_BYTE: return ByteBoxCache::singleton(THREAD)->lookup_raw(value->get_int());
1042 case T_BOOLEAN: return BooleanBoxCache::singleton(THREAD)->lookup_raw(value->get_int());
1043 case T_LONG: return LongBoxCache::singleton(THREAD)->lookup_raw(value->get_int());
1044 default:;
1045 }
1046 }
1047 return NULL;
1048 }
1049
1050 bool Deoptimization::realloc_objects(JavaThread* thread, frame* fr, RegisterMap* reg_map, GrowableArray<ScopeValue*>* objects, TRAPS) {
1051 Handle pending_exception(THREAD, thread->pending_exception());
1052 const char* exception_file = thread->exception_file();
1053 int exception_line = thread->exception_line();
1054 thread->clear_pending_exception();
1055
1056 bool failures = false;
1057
1058 for (int i = 0; i < objects->length(); i++) {
1059 assert(objects->at(i)->is_object(), "invalid debug information");
1060 ObjectValue* sv = (ObjectValue*) objects->at(i);
1061
1062 Klass* k = java_lang_Class::as_Klass(sv->klass()->as_ConstantOopReadValue()->value()());
1063 oop obj = NULL;
1064
1065 if (k->is_instance_klass()) {
1066 if (sv->is_auto_box()) {
1067 AutoBoxObjectValue* abv = (AutoBoxObjectValue*) sv;
1068 obj = get_cached_box(abv, fr, reg_map, THREAD);
1069 if (obj != NULL) {
1070 // Set the flag to indicate the box came from a cache, so that we can skip the field reassignment for it.
1071 abv->set_cached(true);
1072 }
1073 }
1074
1075 InstanceKlass* ik = InstanceKlass::cast(k);
1076 if (obj == NULL) {
1077 #ifdef COMPILER2
1078 if (EnableVectorSupport && VectorSupport::is_vector(ik)) {
1079 obj = VectorSupport::allocate_vector(ik, fr, reg_map, sv, THREAD);
1080 } else {
1081 obj = ik->allocate_instance(THREAD);
1082 }
1083 #else
1084 obj = ik->allocate_instance(THREAD);
1085 #endif // COMPILER2
1086 }
1087 } else if (k->is_typeArray_klass()) {
1088 TypeArrayKlass* ak = TypeArrayKlass::cast(k);
1089 assert(sv->field_size() % type2size[ak->element_type()] == 0, "non-integral array length");
1090 int len = sv->field_size() / type2size[ak->element_type()];
1091 obj = ak->allocate(len, THREAD);
1092 } else if (k->is_objArray_klass()) {
1093 ObjArrayKlass* ak = ObjArrayKlass::cast(k);
1094 obj = ak->allocate(sv->field_size(), THREAD);
1095 }
1096
1097 if (obj == NULL) {
1098 failures = true;
1099 }
1100
1101 assert(sv->value().is_null(), "redundant reallocation");
1102 assert(obj != NULL || HAS_PENDING_EXCEPTION, "allocation should succeed or we should get an exception");
1103 CLEAR_PENDING_EXCEPTION;
1104 sv->set_value(obj);
1105 }
1106
1107 if (failures) {
1108 THROW_OOP_(Universe::out_of_memory_error_realloc_objects(), failures);
1109 } else if (pending_exception.not_null()) {
1110 thread->set_pending_exception(pending_exception(), exception_file, exception_line);
1111 }
1112
1113 return failures;
1114 }
1115
1116 #if INCLUDE_JVMCI
1117 /**
1118 * For primitive types whose kind gets "erased" at runtime (shorts become stack ints),
1119 * we need to somehow be able to recover the actual kind to be able to write the correct
1120 * amount of bytes.
1121 * For that purpose, this method assumes that, for an entry spanning n bytes at index i,
1122 * the entries at index n + 1 to n + i are 'markers'.
1123 * For example, if we were writing a short at index 4 of a byte array of size 8, the
1124 * expected form of the array would be:
1125 *
1126 * {b0, b1, b2, b3, INT, marker, b6, b7}
1127 *
1128 * Thus, in order to get back the size of the entry, we simply need to count the number
1129 * of marked entries
1130 *
1131 * @param virtualArray the virtualized byte array
1132 * @param i index of the virtual entry we are recovering
1133 * @return The number of bytes the entry spans
1134 */
1135 static int count_number_of_bytes_for_entry(ObjectValue *virtualArray, int i) {
1136 int index = i;
1137 while (++index < virtualArray->field_size() &&
1138 virtualArray->field_at(index)->is_marker()) {}
1139 return index - i;
1140 }
1141
1142 /**
1143 * If there was a guarantee for byte array to always start aligned to a long, we could
1144 * do a simple check on the parity of the index. Unfortunately, that is not always the
1145 * case. Thus, we check alignment of the actual address we are writing to.
1146 * In the unlikely case index 0 is 5-aligned for example, it would then be possible to
1147 * write a long to index 3.
1148 */
1149 static jbyte* check_alignment_get_addr(typeArrayOop obj, int index, int expected_alignment) {
1150 jbyte* res = obj->byte_at_addr(index);
1151 assert((((intptr_t) res) % expected_alignment) == 0, "Non-aligned write");
1152 return res;
1153 }
1154
1155 static void byte_array_put(typeArrayOop obj, intptr_t val, int index, int byte_count) {
1156 switch (byte_count) {
1157 case 1:
1158 obj->byte_at_put(index, (jbyte) *((jint *) &val));
1159 break;
1160 case 2:
1161 *((jshort *) check_alignment_get_addr(obj, index, 2)) = (jshort) *((jint *) &val);
1162 break;
1163 case 4:
1164 *((jint *) check_alignment_get_addr(obj, index, 4)) = (jint) *((jint *) &val);
1165 break;
1166 case 8:
1167 *((jlong *) check_alignment_get_addr(obj, index, 8)) = (jlong) *((jlong *) &val);
1168 break;
1169 default:
1170 ShouldNotReachHere();
1171 }
1172 }
1173 #endif // INCLUDE_JVMCI
1174
1175
1176 // restore elements of an eliminated type array
1177 void Deoptimization::reassign_type_array_elements(frame* fr, RegisterMap* reg_map, ObjectValue* sv, typeArrayOop obj, BasicType type) {
1178 int index = 0;
1179 intptr_t val;
1180
1181 for (int i = 0; i < sv->field_size(); i++) {
1182 StackValue* value = StackValue::create_stack_value(fr, reg_map, sv->field_at(i));
1183 switch(type) {
1184 case T_LONG: case T_DOUBLE: {
1185 assert(value->type() == T_INT, "Agreement.");
1186 StackValue* low =
1187 StackValue::create_stack_value(fr, reg_map, sv->field_at(++i));
1188 #ifdef _LP64
1189 jlong res = (jlong)low->get_int();
1190 #else
1191 jlong res = jlong_from((jint)value->get_int(), (jint)low->get_int());
1192 #endif
1193 obj->long_at_put(index, res);
1194 break;
1195 }
1196
1197 // Have to cast to INT (32 bits) pointer to avoid little/big-endian problem.
1198 case T_INT: case T_FLOAT: { // 4 bytes.
1199 assert(value->type() == T_INT, "Agreement.");
1200 bool big_value = false;
1201 if (i + 1 < sv->field_size() && type == T_INT) {
1202 if (sv->field_at(i)->is_location()) {
1203 Location::Type type = ((LocationValue*) sv->field_at(i))->location().type();
1204 if (type == Location::dbl || type == Location::lng) {
1205 big_value = true;
1206 }
1207 } else if (sv->field_at(i)->is_constant_int()) {
1208 ScopeValue* next_scope_field = sv->field_at(i + 1);
1209 if (next_scope_field->is_constant_long() || next_scope_field->is_constant_double()) {
1210 big_value = true;
1211 }
1212 }
1213 }
1214
1215 if (big_value) {
1216 StackValue* low = StackValue::create_stack_value(fr, reg_map, sv->field_at(++i));
1217 #ifdef _LP64
1218 jlong res = (jlong)low->get_int();
1219 #else
1220 jlong res = jlong_from((jint)value->get_int(), (jint)low->get_int());
1221 #endif
1222 obj->int_at_put(index, (jint)*((jint*)&res));
1223 obj->int_at_put(++index, (jint)*(((jint*)&res) + 1));
1224 } else {
1225 val = value->get_int();
1226 obj->int_at_put(index, (jint)*((jint*)&val));
1227 }
1228 break;
1229 }
1230
1231 case T_SHORT:
1232 assert(value->type() == T_INT, "Agreement.");
1233 val = value->get_int();
1234 obj->short_at_put(index, (jshort)*((jint*)&val));
1235 break;
1236
1237 case T_CHAR:
1238 assert(value->type() == T_INT, "Agreement.");
1239 val = value->get_int();
1240 obj->char_at_put(index, (jchar)*((jint*)&val));
1241 break;
1242
1243 case T_BYTE: {
1244 assert(value->type() == T_INT, "Agreement.");
1245 // The value we get is erased as a regular int. We will need to find its actual byte count 'by hand'.
1246 val = value->get_int();
1247 #if INCLUDE_JVMCI
1248 int byte_count = count_number_of_bytes_for_entry(sv, i);
1249 byte_array_put(obj, val, index, byte_count);
1250 // According to byte_count contract, the values from i + 1 to i + byte_count are illegal values. Skip.
1251 i += byte_count - 1; // Balance the loop counter.
1252 index += byte_count;
1253 // index has been updated so continue at top of loop
1254 continue;
1255 #else
1256 obj->byte_at_put(index, (jbyte)*((jint*)&val));
1257 break;
1258 #endif // INCLUDE_JVMCI
1259 }
1260
1261 case T_BOOLEAN: {
1262 assert(value->type() == T_INT, "Agreement.");
1263 val = value->get_int();
1264 obj->bool_at_put(index, (jboolean)*((jint*)&val));
1265 break;
1266 }
1267
1268 default:
1269 ShouldNotReachHere();
1270 }
1271 index++;
1272 }
1273 }
1274
1275 // restore fields of an eliminated object array
1276 void Deoptimization::reassign_object_array_elements(frame* fr, RegisterMap* reg_map, ObjectValue* sv, objArrayOop obj) {
1277 for (int i = 0; i < sv->field_size(); i++) {
1278 StackValue* value = StackValue::create_stack_value(fr, reg_map, sv->field_at(i));
1279 assert(value->type() == T_OBJECT, "object element expected");
1280 obj->obj_at_put(i, value->get_obj()());
1281 }
1282 }
1283
1284 class ReassignedField {
1285 public:
1286 int _offset;
1287 BasicType _type;
1288 public:
1289 ReassignedField() {
1290 _offset = 0;
1291 _type = T_ILLEGAL;
1292 }
1293 };
1294
1295 int compare(ReassignedField* left, ReassignedField* right) {
1296 return left->_offset - right->_offset;
1297 }
1298
1299 // Restore fields of an eliminated instance object using the same field order
1300 // returned by HotSpotResolvedObjectTypeImpl.getInstanceFields(true)
1301 static int reassign_fields_by_klass(InstanceKlass* klass, frame* fr, RegisterMap* reg_map, ObjectValue* sv, int svIndex, oop obj, bool skip_internal) {
1302 GrowableArray<ReassignedField>* fields = new GrowableArray<ReassignedField>();
1303 InstanceKlass* ik = klass;
1304 while (ik != NULL) {
1305 for (AllFieldStream fs(ik); !fs.done(); fs.next()) {
1306 if (!fs.access_flags().is_static() && (!skip_internal || !fs.access_flags().is_internal())) {
1307 ReassignedField field;
1308 field._offset = fs.offset();
1309 field._type = Signature::basic_type(fs.signature());
1310 fields->append(field);
1311 }
1312 }
1313 ik = ik->superklass();
1314 }
1315 fields->sort(compare);
1316 for (int i = 0; i < fields->length(); i++) {
1317 intptr_t val;
1318 ScopeValue* scope_field = sv->field_at(svIndex);
1319 StackValue* value = StackValue::create_stack_value(fr, reg_map, scope_field);
1320 int offset = fields->at(i)._offset;
1321 BasicType type = fields->at(i)._type;
1322 switch (type) {
1323 case T_OBJECT: case T_ARRAY:
1324 assert(value->type() == T_OBJECT, "Agreement.");
1325 obj->obj_field_put(offset, value->get_obj()());
1326 break;
1327
1328 // Have to cast to INT (32 bits) pointer to avoid little/big-endian problem.
1329 case T_INT: case T_FLOAT: { // 4 bytes.
1330 assert(value->type() == T_INT, "Agreement.");
1331 bool big_value = false;
1332 if (i+1 < fields->length() && fields->at(i+1)._type == T_INT) {
1333 if (scope_field->is_location()) {
1334 Location::Type type = ((LocationValue*) scope_field)->location().type();
1335 if (type == Location::dbl || type == Location::lng) {
1336 big_value = true;
1337 }
1338 }
1339 if (scope_field->is_constant_int()) {
1340 ScopeValue* next_scope_field = sv->field_at(svIndex + 1);
1341 if (next_scope_field->is_constant_long() || next_scope_field->is_constant_double()) {
1342 big_value = true;
1343 }
1344 }
1345 }
1346
1347 if (big_value) {
1348 i++;
1349 assert(i < fields->length(), "second T_INT field needed");
1350 assert(fields->at(i)._type == T_INT, "T_INT field needed");
1351 } else {
1352 val = value->get_int();
1353 obj->int_field_put(offset, (jint)*((jint*)&val));
1354 break;
1355 }
1356 }
1357 /* no break */
1358
1359 case T_LONG: case T_DOUBLE: {
1360 assert(value->type() == T_INT, "Agreement.");
1361 StackValue* low = StackValue::create_stack_value(fr, reg_map, sv->field_at(++svIndex));
1362 #ifdef _LP64
1363 jlong res = (jlong)low->get_int();
1364 #else
1365 jlong res = jlong_from((jint)value->get_int(), (jint)low->get_int());
1366 #endif
1367 obj->long_field_put(offset, res);
1368 break;
1369 }
1370
1371 case T_SHORT:
1372 assert(value->type() == T_INT, "Agreement.");
1373 val = value->get_int();
1374 obj->short_field_put(offset, (jshort)*((jint*)&val));
1375 break;
1376
1377 case T_CHAR:
1378 assert(value->type() == T_INT, "Agreement.");
1379 val = value->get_int();
1380 obj->char_field_put(offset, (jchar)*((jint*)&val));
1381 break;
1382
1383 case T_BYTE:
1384 assert(value->type() == T_INT, "Agreement.");
1385 val = value->get_int();
1386 obj->byte_field_put(offset, (jbyte)*((jint*)&val));
1387 break;
1388
1389 case T_BOOLEAN:
1390 assert(value->type() == T_INT, "Agreement.");
1391 val = value->get_int();
1392 obj->bool_field_put(offset, (jboolean)*((jint*)&val));
1393 break;
1394
1395 default:
1396 ShouldNotReachHere();
1397 }
1398 svIndex++;
1399 }
1400 return svIndex;
1401 }
1402
1403 // restore fields of all eliminated objects and arrays
1404 void Deoptimization::reassign_fields(frame* fr, RegisterMap* reg_map, GrowableArray<ScopeValue*>* objects, bool realloc_failures, bool skip_internal) {
1405 for (int i = 0; i < objects->length(); i++) {
1406 ObjectValue* sv = (ObjectValue*) objects->at(i);
1407 Klass* k = java_lang_Class::as_Klass(sv->klass()->as_ConstantOopReadValue()->value()());
1408 Handle obj = sv->value();
1409 assert(obj.not_null() || realloc_failures, "reallocation was missed");
1410 if (PrintDeoptimizationDetails) {
1411 tty->print_cr("reassign fields for object of type %s!", k->name()->as_C_string());
1412 }
1413 if (obj.is_null()) {
1414 continue;
1415 }
1416
1417 // Don't reassign fields of boxes that came from a cache. Caches may be in CDS.
1418 if (sv->is_auto_box() && ((AutoBoxObjectValue*) sv)->is_cached()) {
1419 continue;
1420 }
1421 #ifdef COMPILER2
1422 if (EnableVectorSupport && VectorSupport::is_vector(k)) {
1423 assert(sv->field_size() == 1, "%s not a vector", k->name()->as_C_string());
1424 ScopeValue* payload = sv->field_at(0);
1425 if (payload->is_location() &&
1426 payload->as_LocationValue()->location().type() == Location::vector) {
1427 if (PrintDeoptimizationDetails) {
1428 tty->print_cr("skip field reassignment for this vector - it should be assigned already");
1429 if (Verbose) {
1430 Handle obj = sv->value();
1431 k->oop_print_on(obj(), tty);
1432 }
1433 }
1434 continue; // Such vector's value was already restored in VectorSupport::allocate_vector().
1435 }
1436 // Else fall-through to do assignment for scalar-replaced boxed vector representation
1437 // which could be restored after vector object allocation.
1438 }
1439 #endif
1440 if (k->is_instance_klass()) {
1441 InstanceKlass* ik = InstanceKlass::cast(k);
1442 reassign_fields_by_klass(ik, fr, reg_map, sv, 0, obj(), skip_internal);
1443 } else if (k->is_typeArray_klass()) {
1444 TypeArrayKlass* ak = TypeArrayKlass::cast(k);
1445 reassign_type_array_elements(fr, reg_map, sv, (typeArrayOop) obj(), ak->element_type());
1446 } else if (k->is_objArray_klass()) {
1447 reassign_object_array_elements(fr, reg_map, sv, (objArrayOop) obj());
1448 }
1449 }
1450 }
1451
1452
1453 // relock objects for which synchronization was eliminated
1454 bool Deoptimization::relock_objects(JavaThread* thread, GrowableArray<MonitorInfo*>* monitors,
1455 JavaThread* deoptee_thread, frame& fr, int exec_mode, bool realloc_failures) {
1456 bool relocked_objects = false;
1457 for (int i = 0; i < monitors->length(); i++) {
1458 MonitorInfo* mon_info = monitors->at(i);
1459 if (mon_info->eliminated()) {
1460 assert(!mon_info->owner_is_scalar_replaced() || realloc_failures, "reallocation was missed");
1461 relocked_objects = true;
1462 if (!mon_info->owner_is_scalar_replaced()) {
1463 Handle obj(thread, mon_info->owner());
1464 markWord mark = obj->mark();
1465 if (UseBiasedLocking && mark.has_bias_pattern()) {
1466 // New allocated objects may have the mark set to anonymously biased.
1467 // Also the deoptimized method may called methods with synchronization
1468 // where the thread-local object is bias locked to the current thread.
1469 assert(mark.is_biased_anonymously() ||
1470 mark.biased_locker() == deoptee_thread, "should be locked to current thread");
1471 // Reset mark word to unbiased prototype.
1472 markWord unbiased_prototype = markWord::prototype().set_age(mark.age());
1473 obj->set_mark(unbiased_prototype);
1474 } else if (exec_mode == Unpack_none) {
1475 if (mark.has_locker() && fr.sp() > (intptr_t*)mark.locker()) {
1476 // With exec_mode == Unpack_none obj may be thread local and locked in
1477 // a callee frame. In this case the bias was revoked before in revoke_for_object_deoptimization().
1478 // Make the lock in the callee a recursive lock and restore the displaced header.
1479 markWord dmw = mark.displaced_mark_helper();
1480 mark.locker()->set_displaced_header(markWord::encode((BasicLock*) NULL));
1481 obj->set_mark(dmw);
1482 }
1483 if (mark.has_monitor()) {
1484 // defer relocking if the deoptee thread is currently waiting for obj
1485 ObjectMonitor* waiting_monitor = deoptee_thread->current_waiting_monitor();
1486 if (waiting_monitor != NULL && waiting_monitor->object() == obj()) {
1487 assert(fr.is_deoptimized_frame(), "frame must be scheduled for deoptimization");
1488 mon_info->lock()->set_displaced_header(markWord::unused_mark());
1489 JvmtiDeferredUpdates::inc_relock_count_after_wait(deoptee_thread);
1490 continue;
1491 }
1492 }
1493 }
1494 BasicLock* lock = mon_info->lock();
1495 ObjectSynchronizer::enter(obj, lock, deoptee_thread);
1496 assert(mon_info->owner()->is_locked(), "object must be locked now");
1497 }
1498 }
1499 }
1500 return relocked_objects;
1501 }
1502
1503
1504 #ifndef PRODUCT
1505 // print information about reallocated objects
1506 void Deoptimization::print_objects(GrowableArray<ScopeValue*>* objects, bool realloc_failures) {
1507 fieldDescriptor fd;
1508
1509 for (int i = 0; i < objects->length(); i++) {
1510 ObjectValue* sv = (ObjectValue*) objects->at(i);
1511 Klass* k = java_lang_Class::as_Klass(sv->klass()->as_ConstantOopReadValue()->value()());
1512 Handle obj = sv->value();
1513
1514 tty->print(" object <" INTPTR_FORMAT "> of type ", p2i(sv->value()()));
1515 k->print_value();
1516 assert(obj.not_null() || realloc_failures, "reallocation was missed");
1517 if (obj.is_null()) {
1518 tty->print(" allocation failed");
1519 } else {
1520 tty->print(" allocated (%d bytes)", obj->size() * HeapWordSize);
1521 }
1522 tty->cr();
1523
1524 if (Verbose && !obj.is_null()) {
1525 k->oop_print_on(obj(), tty);
1526 }
1527 }
1528 }
1529 #endif
1530 #endif // COMPILER2_OR_JVMCI
1531
1532 vframeArray* Deoptimization::create_vframeArray(JavaThread* thread, frame fr, RegisterMap *reg_map, GrowableArray<compiledVFrame*>* chunk, bool realloc_failures) {
1533 Events::log_deopt_message(thread, "DEOPT PACKING pc=" INTPTR_FORMAT " sp=" INTPTR_FORMAT, p2i(fr.pc()), p2i(fr.sp()));
1534
1535 #ifndef PRODUCT
1536 if (PrintDeoptimizationDetails) {
1537 ttyLocker ttyl;
1538 tty->print("DEOPT PACKING thread " INTPTR_FORMAT " ", p2i(thread));
1539 fr.print_on(tty);
1540 tty->print_cr(" Virtual frames (innermost first):");
1541 for (int index = 0; index < chunk->length(); index++) {
1542 compiledVFrame* vf = chunk->at(index);
1543 tty->print(" %2d - ", index);
1544 vf->print_value();
1545 int bci = chunk->at(index)->raw_bci();
1546 const char* code_name;
1547 if (bci == SynchronizationEntryBCI) {
1548 code_name = "sync entry";
1549 } else {
1550 Bytecodes::Code code = vf->method()->code_at(bci);
1551 code_name = Bytecodes::name(code);
1552 }
1553 tty->print(" - %s", code_name);
1554 tty->print_cr(" @ bci %d ", bci);
1555 if (Verbose) {
1556 vf->print();
1557 tty->cr();
1558 }
1559 }
1560 }
1561 #endif
1562
1563 // Register map for next frame (used for stack crawl). We capture
1564 // the state of the deopt'ing frame's caller. Thus if we need to
1565 // stuff a C2I adapter we can properly fill in the callee-save
1566 // register locations.
1567 frame caller = fr.sender(reg_map);
1568 int frame_size = caller.sp() - fr.sp();
1569
1570 frame sender = caller;
1571
1572 // Since the Java thread being deoptimized will eventually adjust it's own stack,
1573 // the vframeArray containing the unpacking information is allocated in the C heap.
1574 // For Compiler1, the caller of the deoptimized frame is saved for use by unpack_frames().
1575 vframeArray* array = vframeArray::allocate(thread, frame_size, chunk, reg_map, sender, caller, fr, realloc_failures);
1576
1577 // Compare the vframeArray to the collected vframes
1578 assert(array->structural_compare(thread, chunk), "just checking");
1579
1580 #ifndef PRODUCT
1581 if (PrintDeoptimizationDetails) {
1582 ttyLocker ttyl;
1583 tty->print_cr(" Created vframeArray " INTPTR_FORMAT, p2i(array));
1584 }
1585 #endif // PRODUCT
1586
1587 return array;
1588 }
1589
1590 #if COMPILER2_OR_JVMCI
1591 void Deoptimization::pop_frames_failed_reallocs(JavaThread* thread, vframeArray* array) {
1592 // Reallocation of some scalar replaced objects failed. Record
1593 // that we need to pop all the interpreter frames for the
1594 // deoptimized compiled frame.
1595 assert(thread->frames_to_pop_failed_realloc() == 0, "missed frames to pop?");
1596 thread->set_frames_to_pop_failed_realloc(array->frames());
1597 // Unlock all monitors here otherwise the interpreter will see a
1598 // mix of locked and unlocked monitors (because of failed
1599 // reallocations of synchronized objects) and be confused.
1600 for (int i = 0; i < array->frames(); i++) {
1601 MonitorChunk* monitors = array->element(i)->monitors();
1602 if (monitors != NULL) {
1603 for (int j = 0; j < monitors->number_of_monitors(); j++) {
1604 BasicObjectLock* src = monitors->at(j);
1605 if (src->obj() != NULL) {
1606 ObjectSynchronizer::exit(src->obj(), src->lock(), thread);
1607 }
1608 }
1609 array->element(i)->free_monitors(thread);
1610 #ifdef ASSERT
1611 array->element(i)->set_removed_monitors();
1612 #endif
1613 }
1614 }
1615 }
1616 #endif
1617
1618 static void collect_monitors(compiledVFrame* cvf, GrowableArray<Handle>* objects_to_revoke,
1619 bool only_eliminated) {
1620 GrowableArray<MonitorInfo*>* monitors = cvf->monitors();
1621 Thread* thread = Thread::current();
1622 for (int i = 0; i < monitors->length(); i++) {
1623 MonitorInfo* mon_info = monitors->at(i);
1624 if (mon_info->eliminated() == only_eliminated &&
1625 !mon_info->owner_is_scalar_replaced() &&
1626 mon_info->owner() != NULL) {
1627 objects_to_revoke->append(Handle(thread, mon_info->owner()));
1628 }
1629 }
1630 }
1631
1632 static void get_monitors_from_stack(GrowableArray<Handle>* objects_to_revoke, JavaThread* thread,
1633 frame fr, RegisterMap* map, bool only_eliminated) {
1634 // Unfortunately we don't have a RegisterMap available in most of
1635 // the places we want to call this routine so we need to walk the
1636 // stack again to update the register map.
1637 if (map == NULL || !map->update_map()) {
1638 StackFrameStream sfs(thread, true /* update */, true /* process_frames */);
1639 bool found = false;
1640 while (!found && !sfs.is_done()) {
1641 frame* cur = sfs.current();
1642 sfs.next();
1643 found = cur->id() == fr.id();
1644 }
1645 assert(found, "frame to be deoptimized not found on target thread's stack");
1646 map = sfs.register_map();
1647 }
1648
1649 vframe* vf = vframe::new_vframe(&fr, map, thread);
1650 compiledVFrame* cvf = compiledVFrame::cast(vf);
1651 // Revoke monitors' biases in all scopes
1652 while (!cvf->is_top()) {
1653 collect_monitors(cvf, objects_to_revoke, only_eliminated);
1654 cvf = compiledVFrame::cast(cvf->sender());
1655 }
1656 collect_monitors(cvf, objects_to_revoke, only_eliminated);
1657 }
1658
1659 void Deoptimization::revoke_from_deopt_handler(JavaThread* thread, frame fr, RegisterMap* map) {
1660 if (!UseBiasedLocking) {
1661 return;
1662 }
1663 assert(thread == Thread::current(), "should be");
1664 ResourceMark rm(thread);
1665 HandleMark hm(thread);
1666 GrowableArray<Handle>* objects_to_revoke = new GrowableArray<Handle>();
1667 get_monitors_from_stack(objects_to_revoke, thread, fr, map, false);
1668
1669 int len = objects_to_revoke->length();
1670 for (int i = 0; i < len; i++) {
1671 oop obj = (objects_to_revoke->at(i))();
1672 BiasedLocking::revoke_own_lock(thread, objects_to_revoke->at(i));
1673 assert(!obj->mark().has_bias_pattern(), "biases should be revoked by now");
1674 }
1675 }
1676
1677 // Revoke the bias of objects with eliminated locking to prepare subsequent relocking.
1678 void Deoptimization::revoke_for_object_deoptimization(JavaThread* deoptee_thread, frame fr,
1679 RegisterMap* map, JavaThread* thread) {
1680 if (!UseBiasedLocking) {
1681 return;
1682 }
1683 GrowableArray<Handle>* objects_to_revoke = new GrowableArray<Handle>();
1684 assert(KeepStackGCProcessedMark::stack_is_kept_gc_processed(deoptee_thread), "must be");
1685 // Collect monitors but only those with eliminated locking.
1686 get_monitors_from_stack(objects_to_revoke, deoptee_thread, fr, map, true);
1687
1688 int len = objects_to_revoke->length();
1689 for (int i = 0; i < len; i++) {
1690 oop obj = (objects_to_revoke->at(i))();
1691 markWord mark = obj->mark();
1692 if (!mark.has_bias_pattern() ||
1693 mark.is_biased_anonymously() || // eliminated locking does not bias an object if it wasn't before
1694 !obj->klass()->prototype_header().has_bias_pattern() || // bulk revoke ignores eliminated monitors
1695 (obj->klass()->prototype_header().bias_epoch() != mark.bias_epoch())) { // bulk rebias ignores eliminated monitors
1696 // We reach here regularly if there's just eliminated locking on obj.
1697 // We must not call BiasedLocking::revoke_own_lock() in this case, as we
1698 // would hit assertions because it is a prerequisite that there has to be
1699 // non-eliminated locking on obj by deoptee_thread.
1700 // Luckily we don't have to revoke here because obj has to be a
1701 // non-escaping obj and can be relocked without revoking the bias. See
1702 // Deoptimization::relock_objects().
1703 continue;
1704 }
1705 BiasedLocking::revoke(thread, objects_to_revoke->at(i));
1706 assert(!objects_to_revoke->at(i)->mark().has_bias_pattern(), "biases should be revoked by now");
1707 }
1708 }
1709
1710 void Deoptimization::deoptimize_single_frame(JavaThread* thread, frame fr, Deoptimization::DeoptReason reason) {
1711 assert(fr.can_be_deoptimized(), "checking frame type");
1712
1713 gather_statistics(reason, Action_none, Bytecodes::_illegal);
1714
1715 if (LogCompilation && xtty != NULL) {
1716 CompiledMethod* cm = fr.cb()->as_compiled_method_or_null();
1717 assert(cm != NULL, "only compiled methods can deopt");
1718
1719 ttyLocker ttyl;
1720 xtty->begin_head("deoptimized thread='" UINTX_FORMAT "' reason='%s' pc='" INTPTR_FORMAT "'",(uintx)thread->osthread()->thread_id(), trap_reason_name(reason), p2i(fr.pc()));
1721 cm->log_identity(xtty);
1722 xtty->end_head();
1723 for (ScopeDesc* sd = cm->scope_desc_at(fr.pc()); ; sd = sd->sender()) {
1724 xtty->begin_elem("jvms bci='%d'", sd->bci());
1725 xtty->method(sd->method());
1726 xtty->end_elem();
1727 if (sd->is_top()) break;
1728 }
1729 xtty->tail("deoptimized");
1730 }
1731
1732 // Patch the compiled method so that when execution returns to it we will
1733 // deopt the execution state and return to the interpreter.
1734 fr.deoptimize(thread);
1735 }
1736
1737 void Deoptimization::deoptimize(JavaThread* thread, frame fr, DeoptReason reason) {
1738 // Deoptimize only if the frame comes from compile code.
1739 // Do not deoptimize the frame which is already patched
1740 // during the execution of the loops below.
1741 if (!fr.is_compiled_frame() || fr.is_deoptimized_frame()) {
1742 return;
1743 }
1744 ResourceMark rm;
1745 DeoptimizationMarker dm;
1746 deoptimize_single_frame(thread, fr, reason);
1747 }
1748
1749 #if INCLUDE_JVMCI
1750 address Deoptimization::deoptimize_for_missing_exception_handler(CompiledMethod* cm) {
1751 // there is no exception handler for this pc => deoptimize
1752 cm->make_not_entrant();
1753
1754 // Use Deoptimization::deoptimize for all of its side-effects:
1755 // gathering traps statistics, logging...
1756 // it also patches the return pc but we do not care about that
1757 // since we return a continuation to the deopt_blob below.
1758 JavaThread* thread = JavaThread::current();
1759 RegisterMap reg_map(thread, false);
1760 frame runtime_frame = thread->last_frame();
1761 frame caller_frame = runtime_frame.sender(®_map);
1762 assert(caller_frame.cb()->as_compiled_method_or_null() == cm, "expect top frame compiled method");
1763 vframe* vf = vframe::new_vframe(&caller_frame, ®_map, thread);
1764 compiledVFrame* cvf = compiledVFrame::cast(vf);
1765 ScopeDesc* imm_scope = cvf->scope();
1766 MethodData* imm_mdo = get_method_data(thread, methodHandle(thread, imm_scope->method()), true);
1767 if (imm_mdo != NULL) {
1768 ProfileData* pdata = imm_mdo->allocate_bci_to_data(imm_scope->bci(), NULL);
1769 if (pdata != NULL && pdata->is_BitData()) {
1770 BitData* bit_data = (BitData*) pdata;
1771 bit_data->set_exception_seen();
1772 }
1773 }
1774
1775 Deoptimization::deoptimize(thread, caller_frame, Deoptimization::Reason_not_compiled_exception_handler);
1776
1777 MethodData* trap_mdo = get_method_data(thread, methodHandle(thread, cm->method()), true);
1778 if (trap_mdo != NULL) {
1779 trap_mdo->inc_trap_count(Deoptimization::Reason_not_compiled_exception_handler);
1780 }
1781
1782 return SharedRuntime::deopt_blob()->unpack_with_exception_in_tls();
1783 }
1784 #endif
1785
1786 void Deoptimization::deoptimize_frame_internal(JavaThread* thread, intptr_t* id, DeoptReason reason) {
1787 assert(thread == Thread::current() ||
1788 thread->is_handshake_safe_for(Thread::current()) ||
1789 SafepointSynchronize::is_at_safepoint(),
1790 "can only deoptimize other thread at a safepoint/handshake");
1791 // Compute frame and register map based on thread and sp.
1792 RegisterMap reg_map(thread, false);
1793 frame fr = thread->last_frame();
1794 while (fr.id() != id) {
1795 fr = fr.sender(®_map);
1796 }
1797 deoptimize(thread, fr, reason);
1798 }
1799
1800
1801 void Deoptimization::deoptimize_frame(JavaThread* thread, intptr_t* id, DeoptReason reason) {
1802 Thread* current = Thread::current();
1803 if (thread == current || thread->is_handshake_safe_for(current)) {
1804 Deoptimization::deoptimize_frame_internal(thread, id, reason);
1805 } else {
1806 VM_DeoptimizeFrame deopt(thread, id, reason);
1807 VMThread::execute(&deopt);
1808 }
1809 }
1810
1811 void Deoptimization::deoptimize_frame(JavaThread* thread, intptr_t* id) {
1812 deoptimize_frame(thread, id, Reason_constraint);
1813 }
1814
1815 // JVMTI PopFrame support
1816 JRT_LEAF(void, Deoptimization::popframe_preserve_args(JavaThread* thread, int bytes_to_save, void* start_address))
1817 {
1818 thread->popframe_preserve_args(in_ByteSize(bytes_to_save), start_address);
1819 }
1820 JRT_END
1821
1822 MethodData*
1823 Deoptimization::get_method_data(JavaThread* thread, const methodHandle& m,
1824 bool create_if_missing) {
1825 JavaThread* THREAD = thread; // For exception macros.
1826 MethodData* mdo = m()->method_data();
1827 if (mdo == NULL && create_if_missing && !HAS_PENDING_EXCEPTION) {
1828 // Build an MDO. Ignore errors like OutOfMemory;
1829 // that simply means we won't have an MDO to update.
1830 Method::build_interpreter_method_data(m, THREAD);
1831 if (HAS_PENDING_EXCEPTION) {
1832 // Only metaspace OOM is expected. No Java code executed.
1833 assert((PENDING_EXCEPTION->is_a(vmClasses::OutOfMemoryError_klass())), "we expect only an OOM error here");
1834 CLEAR_PENDING_EXCEPTION;
1835 }
1836 mdo = m()->method_data();
1837 }
1838 return mdo;
1839 }
1840
1841 #if COMPILER2_OR_JVMCI
1842 void Deoptimization::load_class_by_index(const constantPoolHandle& constant_pool, int index, TRAPS) {
1843 // In case of an unresolved klass entry, load the class.
1844 // This path is exercised from case _ldc in Parse::do_one_bytecode,
1845 // and probably nowhere else.
1846 // Even that case would benefit from simply re-interpreting the
1847 // bytecode, without paying special attention to the class index.
1848 // So this whole "class index" feature should probably be removed.
1849
1850 if (constant_pool->tag_at(index).is_unresolved_klass()) {
1851 Klass* tk = constant_pool->klass_at(index, THREAD);
1852 if (HAS_PENDING_EXCEPTION) {
1853 // Exception happened during classloading. We ignore the exception here, since it
1854 // is going to be rethrown since the current activation is going to be deoptimized and
1855 // the interpreter will re-execute the bytecode.
1856 // Do not clear probable Async Exceptions.
1857 CLEAR_PENDING_NONASYNC_EXCEPTION;
1858 // Class loading called java code which may have caused a stack
1859 // overflow. If the exception was thrown right before the return
1860 // to the runtime the stack is no longer guarded. Reguard the
1861 // stack otherwise if we return to the uncommon trap blob and the
1862 // stack bang causes a stack overflow we crash.
1863 JavaThread* jt = THREAD;
1864 bool guard_pages_enabled = jt->stack_overflow_state()->reguard_stack_if_needed();
1865 assert(guard_pages_enabled, "stack banging in uncommon trap blob may cause crash");
1866 }
1867 return;
1868 }
1869
1870 assert(!constant_pool->tag_at(index).is_symbol(),
1871 "no symbolic names here, please");
1872 }
1873
1874 #if INCLUDE_JFR
1875
1876 class DeoptReasonSerializer : public JfrSerializer {
1877 public:
1878 void serialize(JfrCheckpointWriter& writer) {
1879 writer.write_count((u4)(Deoptimization::Reason_LIMIT + 1)); // + Reason::many (-1)
1880 for (int i = -1; i < Deoptimization::Reason_LIMIT; ++i) {
1881 writer.write_key((u8)i);
1882 writer.write(Deoptimization::trap_reason_name(i));
1883 }
1884 }
1885 };
1886
1887 class DeoptActionSerializer : public JfrSerializer {
1888 public:
1889 void serialize(JfrCheckpointWriter& writer) {
1890 static const u4 nof_actions = Deoptimization::Action_LIMIT;
1891 writer.write_count(nof_actions);
1892 for (u4 i = 0; i < Deoptimization::Action_LIMIT; ++i) {
1893 writer.write_key(i);
1894 writer.write(Deoptimization::trap_action_name((int)i));
1895 }
1896 }
1897 };
1898
1899 static void register_serializers() {
1900 static int critical_section = 0;
1901 if (1 == critical_section || Atomic::cmpxchg(&critical_section, 0, 1) == 1) {
1902 return;
1903 }
1904 JfrSerializer::register_serializer(TYPE_DEOPTIMIZATIONREASON, true, new DeoptReasonSerializer());
1905 JfrSerializer::register_serializer(TYPE_DEOPTIMIZATIONACTION, true, new DeoptActionSerializer());
1906 }
1907
1908 static void post_deoptimization_event(CompiledMethod* nm,
1909 const Method* method,
1910 int trap_bci,
1911 int instruction,
1912 Deoptimization::DeoptReason reason,
1913 Deoptimization::DeoptAction action) {
1914 assert(nm != NULL, "invariant");
1915 assert(method != NULL, "invariant");
1916 if (EventDeoptimization::is_enabled()) {
1917 static bool serializers_registered = false;
1918 if (!serializers_registered) {
1919 register_serializers();
1920 serializers_registered = true;
1921 }
1922 EventDeoptimization event;
1923 event.set_compileId(nm->compile_id());
1924 event.set_compiler(nm->compiler_type());
1925 event.set_method(method);
1926 event.set_lineNumber(method->line_number_from_bci(trap_bci));
1927 event.set_bci(trap_bci);
1928 event.set_instruction(instruction);
1929 event.set_reason(reason);
1930 event.set_action(action);
1931 event.commit();
1932 }
1933 }
1934
1935 #endif // INCLUDE_JFR
1936
1937 JRT_ENTRY(void, Deoptimization::uncommon_trap_inner(JavaThread* current, jint trap_request)) {
1938 HandleMark hm(current);
1939
1940 // uncommon_trap() is called at the beginning of the uncommon trap
1941 // handler. Note this fact before we start generating temporary frames
1942 // that can confuse an asynchronous stack walker. This counter is
1943 // decremented at the end of unpack_frames().
1944 current->inc_in_deopt_handler();
1945
1946 // We need to update the map if we have biased locking.
1947 #if INCLUDE_JVMCI
1948 // JVMCI might need to get an exception from the stack, which in turn requires the register map to be valid
1949 RegisterMap reg_map(current, true);
1950 #else
1951 RegisterMap reg_map(current, UseBiasedLocking);
1952 #endif
1953 frame stub_frame = current->last_frame();
1954 frame fr = stub_frame.sender(®_map);
1955 // Make sure the calling nmethod is not getting deoptimized and removed
1956 // before we are done with it.
1957 nmethodLocker nl(fr.pc());
1958
1959 // Log a message
1960 Events::log_deopt_message(current, "Uncommon trap: trap_request=" PTR32_FORMAT " fr.pc=" INTPTR_FORMAT " relative=" INTPTR_FORMAT,
1961 trap_request, p2i(fr.pc()), fr.pc() - fr.cb()->code_begin());
1962
1963 {
1964 ResourceMark rm;
1965
1966 DeoptReason reason = trap_request_reason(trap_request);
1967 DeoptAction action = trap_request_action(trap_request);
1968 #if INCLUDE_JVMCI
1969 int debug_id = trap_request_debug_id(trap_request);
1970 #endif
1971 jint unloaded_class_index = trap_request_index(trap_request); // CP idx or -1
1972
1973 vframe* vf = vframe::new_vframe(&fr, ®_map, current);
1974 compiledVFrame* cvf = compiledVFrame::cast(vf);
1975
1976 CompiledMethod* nm = cvf->code();
1977
1978 ScopeDesc* trap_scope = cvf->scope();
1979
1980 bool is_receiver_constraint_failure = COMPILER2_PRESENT(VerifyReceiverTypes &&) (reason == Deoptimization::Reason_receiver_constraint);
1981
1982 if (TraceDeoptimization || is_receiver_constraint_failure) {
1983 ttyLocker ttyl;
1984 tty->print_cr(" bci=%d pc=" INTPTR_FORMAT ", relative_pc=" INTPTR_FORMAT ", method=%s" JVMCI_ONLY(", debug_id=%d"), trap_scope->bci(), p2i(fr.pc()), fr.pc() - nm->code_begin(), trap_scope->method()->name_and_sig_as_C_string()
1985 #if INCLUDE_JVMCI
1986 , debug_id
1987 #endif
1988 );
1989 }
1990
1991 methodHandle trap_method(current, trap_scope->method());
1992 int trap_bci = trap_scope->bci();
1993 #if INCLUDE_JVMCI
1994 jlong speculation = current->pending_failed_speculation();
1995 if (nm->is_compiled_by_jvmci()) {
1996 nm->as_nmethod()->update_speculation(current);
1997 } else {
1998 assert(speculation == 0, "There should not be a speculation for methods compiled by non-JVMCI compilers");
1999 }
2000
2001 if (trap_bci == SynchronizationEntryBCI) {
2002 trap_bci = 0;
2003 current->set_pending_monitorenter(true);
2004 }
2005
2006 if (reason == Deoptimization::Reason_transfer_to_interpreter) {
2007 current->set_pending_transfer_to_interpreter(true);
2008 }
2009 #endif
2010
2011 Bytecodes::Code trap_bc = trap_method->java_code_at(trap_bci);
2012 // Record this event in the histogram.
2013 gather_statistics(reason, action, trap_bc);
2014
2015 // Ensure that we can record deopt. history:
2016 // Need MDO to record RTM code generation state.
2017 bool create_if_missing = ProfileTraps || UseCodeAging RTM_OPT_ONLY( || UseRTMLocking );
2018
2019 methodHandle profiled_method;
2020 #if INCLUDE_JVMCI
2021 if (nm->is_compiled_by_jvmci()) {
2022 profiled_method = methodHandle(current, nm->method());
2023 } else {
2024 profiled_method = trap_method;
2025 }
2026 #else
2027 profiled_method = trap_method;
2028 #endif
2029
2030 MethodData* trap_mdo =
2031 get_method_data(current, profiled_method, create_if_missing);
2032
2033 JFR_ONLY(post_deoptimization_event(nm, trap_method(), trap_bci, trap_bc, reason, action);)
2034
2035 // Log a message
2036 Events::log_deopt_message(current, "Uncommon trap: reason=%s action=%s pc=" INTPTR_FORMAT " method=%s @ %d %s",
2037 trap_reason_name(reason), trap_action_name(action), p2i(fr.pc()),
2038 trap_method->name_and_sig_as_C_string(), trap_bci, nm->compiler_name());
2039
2040 // Print a bunch of diagnostics, if requested.
2041 if (TraceDeoptimization || LogCompilation || is_receiver_constraint_failure) {
2042 ResourceMark rm;
2043 ttyLocker ttyl;
2044 char buf[100];
2045 if (xtty != NULL) {
2046 xtty->begin_head("uncommon_trap thread='" UINTX_FORMAT "' %s",
2047 os::current_thread_id(),
2048 format_trap_request(buf, sizeof(buf), trap_request));
2049 #if INCLUDE_JVMCI
2050 if (speculation != 0) {
2051 xtty->print(" speculation='" JLONG_FORMAT "'", speculation);
2052 }
2053 #endif
2054 nm->log_identity(xtty);
2055 }
2056 Symbol* class_name = NULL;
2057 bool unresolved = false;
2058 if (unloaded_class_index >= 0) {
2059 constantPoolHandle constants (current, trap_method->constants());
2060 if (constants->tag_at(unloaded_class_index).is_unresolved_klass()) {
2061 class_name = constants->klass_name_at(unloaded_class_index);
2062 unresolved = true;
2063 if (xtty != NULL)
2064 xtty->print(" unresolved='1'");
2065 } else if (constants->tag_at(unloaded_class_index).is_symbol()) {
2066 class_name = constants->symbol_at(unloaded_class_index);
2067 }
2068 if (xtty != NULL)
2069 xtty->name(class_name);
2070 }
2071 if (xtty != NULL && trap_mdo != NULL && (int)reason < (int)MethodData::_trap_hist_limit) {
2072 // Dump the relevant MDO state.
2073 // This is the deopt count for the current reason, any previous
2074 // reasons or recompiles seen at this point.
2075 int dcnt = trap_mdo->trap_count(reason);
2076 if (dcnt != 0)
2077 xtty->print(" count='%d'", dcnt);
2078 ProfileData* pdata = trap_mdo->bci_to_data(trap_bci);
2079 int dos = (pdata == NULL)? 0: pdata->trap_state();
2080 if (dos != 0) {
2081 xtty->print(" state='%s'", format_trap_state(buf, sizeof(buf), dos));
2082 if (trap_state_is_recompiled(dos)) {
2083 int recnt2 = trap_mdo->overflow_recompile_count();
2084 if (recnt2 != 0)
2085 xtty->print(" recompiles2='%d'", recnt2);
2086 }
2087 }
2088 }
2089 if (xtty != NULL) {
2090 xtty->stamp();
2091 xtty->end_head();
2092 }
2093 if (TraceDeoptimization) { // make noise on the tty
2094 tty->print("Uncommon trap occurred in");
2095 nm->method()->print_short_name(tty);
2096 tty->print(" compiler=%s compile_id=%d", nm->compiler_name(), nm->compile_id());
2097 #if INCLUDE_JVMCI
2098 if (nm->is_nmethod()) {
2099 const char* installed_code_name = nm->as_nmethod()->jvmci_name();
2100 if (installed_code_name != NULL) {
2101 tty->print(" (JVMCI: installed code name=%s) ", installed_code_name);
2102 }
2103 }
2104 #endif
2105 tty->print(" (@" INTPTR_FORMAT ") thread=" UINTX_FORMAT " reason=%s action=%s unloaded_class_index=%d" JVMCI_ONLY(" debug_id=%d"),
2106 p2i(fr.pc()),
2107 os::current_thread_id(),
2108 trap_reason_name(reason),
2109 trap_action_name(action),
2110 unloaded_class_index
2111 #if INCLUDE_JVMCI
2112 , debug_id
2113 #endif
2114 );
2115 if (class_name != NULL) {
2116 tty->print(unresolved ? " unresolved class: " : " symbol: ");
2117 class_name->print_symbol_on(tty);
2118 }
2119 tty->cr();
2120 }
2121 if (xtty != NULL) {
2122 // Log the precise location of the trap.
2123 for (ScopeDesc* sd = trap_scope; ; sd = sd->sender()) {
2124 xtty->begin_elem("jvms bci='%d'", sd->bci());
2125 xtty->method(sd->method());
2126 xtty->end_elem();
2127 if (sd->is_top()) break;
2128 }
2129 xtty->tail("uncommon_trap");
2130 }
2131 }
2132 // (End diagnostic printout.)
2133
2134 if (is_receiver_constraint_failure) {
2135 fatal("missing receiver type check");
2136 }
2137
2138 // Load class if necessary
2139 if (unloaded_class_index >= 0) {
2140 constantPoolHandle constants(current, trap_method->constants());
2141 load_class_by_index(constants, unloaded_class_index, THREAD);
2142 }
2143
2144 // Flush the nmethod if necessary and desirable.
2145 //
2146 // We need to avoid situations where we are re-flushing the nmethod
2147 // because of a hot deoptimization site. Repeated flushes at the same
2148 // point need to be detected by the compiler and avoided. If the compiler
2149 // cannot avoid them (or has a bug and "refuses" to avoid them), this
2150 // module must take measures to avoid an infinite cycle of recompilation
2151 // and deoptimization. There are several such measures:
2152 //
2153 // 1. If a recompilation is ordered a second time at some site X
2154 // and for the same reason R, the action is adjusted to 'reinterpret',
2155 // to give the interpreter time to exercise the method more thoroughly.
2156 // If this happens, the method's overflow_recompile_count is incremented.
2157 //
2158 // 2. If the compiler fails to reduce the deoptimization rate, then
2159 // the method's overflow_recompile_count will begin to exceed the set
2160 // limit PerBytecodeRecompilationCutoff. If this happens, the action
2161 // is adjusted to 'make_not_compilable', and the method is abandoned
2162 // to the interpreter. This is a performance hit for hot methods,
2163 // but is better than a disastrous infinite cycle of recompilations.
2164 // (Actually, only the method containing the site X is abandoned.)
2165 //
2166 // 3. In parallel with the previous measures, if the total number of
2167 // recompilations of a method exceeds the much larger set limit
2168 // PerMethodRecompilationCutoff, the method is abandoned.
2169 // This should only happen if the method is very large and has
2170 // many "lukewarm" deoptimizations. The code which enforces this
2171 // limit is elsewhere (class nmethod, class Method).
2172 //
2173 // Note that the per-BCI 'is_recompiled' bit gives the compiler one chance
2174 // to recompile at each bytecode independently of the per-BCI cutoff.
2175 //
2176 // The decision to update code is up to the compiler, and is encoded
2177 // in the Action_xxx code. If the compiler requests Action_none
2178 // no trap state is changed, no compiled code is changed, and the
2179 // computation suffers along in the interpreter.
2180 //
2181 // The other action codes specify various tactics for decompilation
2182 // and recompilation. Action_maybe_recompile is the loosest, and
2183 // allows the compiled code to stay around until enough traps are seen,
2184 // and until the compiler gets around to recompiling the trapping method.
2185 //
2186 // The other actions cause immediate removal of the present code.
2187
2188 // Traps caused by injected profile shouldn't pollute trap counts.
2189 bool injected_profile_trap = trap_method->has_injected_profile() &&
2190 (reason == Reason_intrinsic || reason == Reason_unreached);
2191
2192 bool update_trap_state = (reason != Reason_tenured) && !injected_profile_trap;
2193 bool make_not_entrant = false;
2194 bool make_not_compilable = false;
2195 bool reprofile = false;
2196 switch (action) {
2197 case Action_none:
2198 // Keep the old code.
2199 update_trap_state = false;
2200 break;
2201 case Action_maybe_recompile:
2202 // Do not need to invalidate the present code, but we can
2203 // initiate another
2204 // Start compiler without (necessarily) invalidating the nmethod.
2205 // The system will tolerate the old code, but new code should be
2206 // generated when possible.
2207 break;
2208 case Action_reinterpret:
2209 // Go back into the interpreter for a while, and then consider
2210 // recompiling form scratch.
2211 make_not_entrant = true;
2212 // Reset invocation counter for outer most method.
2213 // This will allow the interpreter to exercise the bytecodes
2214 // for a while before recompiling.
2215 // By contrast, Action_make_not_entrant is immediate.
2216 //
2217 // Note that the compiler will track null_check, null_assert,
2218 // range_check, and class_check events and log them as if they
2219 // had been traps taken from compiled code. This will update
2220 // the MDO trap history so that the next compilation will
2221 // properly detect hot trap sites.
2222 reprofile = true;
2223 break;
2224 case Action_make_not_entrant:
2225 // Request immediate recompilation, and get rid of the old code.
2226 // Make them not entrant, so next time they are called they get
2227 // recompiled. Unloaded classes are loaded now so recompile before next
2228 // time they are called. Same for uninitialized. The interpreter will
2229 // link the missing class, if any.
2230 make_not_entrant = true;
2231 break;
2232 case Action_make_not_compilable:
2233 // Give up on compiling this method at all.
2234 make_not_entrant = true;
2235 make_not_compilable = true;
2236 break;
2237 default:
2238 ShouldNotReachHere();
2239 }
2240
2241 // Setting +ProfileTraps fixes the following, on all platforms:
2242 // 4852688: ProfileInterpreter is off by default for ia64. The result is
2243 // infinite heroic-opt-uncommon-trap/deopt/recompile cycles, since the
2244 // recompile relies on a MethodData* to record heroic opt failures.
2245
2246 // Whether the interpreter is producing MDO data or not, we also need
2247 // to use the MDO to detect hot deoptimization points and control
2248 // aggressive optimization.
2249 bool inc_recompile_count = false;
2250 ProfileData* pdata = NULL;
2251 if (ProfileTraps && CompilerConfig::is_c2_or_jvmci_compiler_enabled() && update_trap_state && trap_mdo != NULL) {
2252 assert(trap_mdo == get_method_data(current, profiled_method, false), "sanity");
2253 uint this_trap_count = 0;
2254 bool maybe_prior_trap = false;
2255 bool maybe_prior_recompile = false;
2256 pdata = query_update_method_data(trap_mdo, trap_bci, reason, true,
2257 #if INCLUDE_JVMCI
2258 nm->is_compiled_by_jvmci() && nm->is_osr_method(),
2259 #endif
2260 nm->method(),
2261 //outputs:
2262 this_trap_count,
2263 maybe_prior_trap,
2264 maybe_prior_recompile);
2265 // Because the interpreter also counts null, div0, range, and class
2266 // checks, these traps from compiled code are double-counted.
2267 // This is harmless; it just means that the PerXTrapLimit values
2268 // are in effect a little smaller than they look.
2269
2270 DeoptReason per_bc_reason = reason_recorded_per_bytecode_if_any(reason);
2271 if (per_bc_reason != Reason_none) {
2272 // Now take action based on the partially known per-BCI history.
2273 if (maybe_prior_trap
2274 && this_trap_count >= (uint)PerBytecodeTrapLimit) {
2275 // If there are too many traps at this BCI, force a recompile.
2276 // This will allow the compiler to see the limit overflow, and
2277 // take corrective action, if possible. The compiler generally
2278 // does not use the exact PerBytecodeTrapLimit value, but instead
2279 // changes its tactics if it sees any traps at all. This provides
2280 // a little hysteresis, delaying a recompile until a trap happens
2281 // several times.
2282 //
2283 // Actually, since there is only one bit of counter per BCI,
2284 // the possible per-BCI counts are {0,1,(per-method count)}.
2285 // This produces accurate results if in fact there is only
2286 // one hot trap site, but begins to get fuzzy if there are
2287 // many sites. For example, if there are ten sites each
2288 // trapping two or more times, they each get the blame for
2289 // all of their traps.
2290 make_not_entrant = true;
2291 }
2292
2293 // Detect repeated recompilation at the same BCI, and enforce a limit.
2294 if (make_not_entrant && maybe_prior_recompile) {
2295 // More than one recompile at this point.
2296 inc_recompile_count = maybe_prior_trap;
2297 }
2298 } else {
2299 // For reasons which are not recorded per-bytecode, we simply
2300 // force recompiles unconditionally.
2301 // (Note that PerMethodRecompilationCutoff is enforced elsewhere.)
2302 make_not_entrant = true;
2303 }
2304
2305 // Go back to the compiler if there are too many traps in this method.
2306 if (this_trap_count >= per_method_trap_limit(reason)) {
2307 // If there are too many traps in this method, force a recompile.
2308 // This will allow the compiler to see the limit overflow, and
2309 // take corrective action, if possible.
2310 // (This condition is an unlikely backstop only, because the
2311 // PerBytecodeTrapLimit is more likely to take effect first,
2312 // if it is applicable.)
2313 make_not_entrant = true;
2314 }
2315
2316 // Here's more hysteresis: If there has been a recompile at
2317 // this trap point already, run the method in the interpreter
2318 // for a while to exercise it more thoroughly.
2319 if (make_not_entrant && maybe_prior_recompile && maybe_prior_trap) {
2320 reprofile = true;
2321 }
2322 }
2323
2324 // Take requested actions on the method:
2325
2326 // Recompile
2327 if (make_not_entrant) {
2328 if (!nm->make_not_entrant()) {
2329 return; // the call did not change nmethod's state
2330 }
2331
2332 if (pdata != NULL) {
2333 // Record the recompilation event, if any.
2334 int tstate0 = pdata->trap_state();
2335 int tstate1 = trap_state_set_recompiled(tstate0, true);
2336 if (tstate1 != tstate0)
2337 pdata->set_trap_state(tstate1);
2338 }
2339
2340 #if INCLUDE_RTM_OPT
2341 // Restart collecting RTM locking abort statistic if the method
2342 // is recompiled for a reason other than RTM state change.
2343 // Assume that in new recompiled code the statistic could be different,
2344 // for example, due to different inlining.
2345 if ((reason != Reason_rtm_state_change) && (trap_mdo != NULL) &&
2346 UseRTMDeopt && (nm->as_nmethod()->rtm_state() != ProfileRTM)) {
2347 trap_mdo->atomic_set_rtm_state(ProfileRTM);
2348 }
2349 #endif
2350 // For code aging we count traps separately here, using make_not_entrant()
2351 // as a guard against simultaneous deopts in multiple threads.
2352 if (reason == Reason_tenured && trap_mdo != NULL) {
2353 trap_mdo->inc_tenure_traps();
2354 }
2355 }
2356
2357 if (inc_recompile_count) {
2358 trap_mdo->inc_overflow_recompile_count();
2359 if ((uint)trap_mdo->overflow_recompile_count() >
2360 (uint)PerBytecodeRecompilationCutoff) {
2361 // Give up on the method containing the bad BCI.
2362 if (trap_method() == nm->method()) {
2363 make_not_compilable = true;
2364 } else {
2365 trap_method->set_not_compilable("overflow_recompile_count > PerBytecodeRecompilationCutoff", CompLevel_full_optimization);
2366 // But give grace to the enclosing nm->method().
2367 }
2368 }
2369 }
2370
2371 // Reprofile
2372 if (reprofile) {
2373 CompilationPolicy::reprofile(trap_scope, nm->is_osr_method());
2374 }
2375
2376 // Give up compiling
2377 if (make_not_compilable && !nm->method()->is_not_compilable(CompLevel_full_optimization)) {
2378 assert(make_not_entrant, "consistent");
2379 nm->method()->set_not_compilable("give up compiling", CompLevel_full_optimization);
2380 }
2381
2382 } // Free marked resources
2383
2384 }
2385 JRT_END
2386
2387 ProfileData*
2388 Deoptimization::query_update_method_data(MethodData* trap_mdo,
2389 int trap_bci,
2390 Deoptimization::DeoptReason reason,
2391 bool update_total_trap_count,
2392 #if INCLUDE_JVMCI
2393 bool is_osr,
2394 #endif
2395 Method* compiled_method,
2396 //outputs:
2397 uint& ret_this_trap_count,
2398 bool& ret_maybe_prior_trap,
2399 bool& ret_maybe_prior_recompile) {
2400 bool maybe_prior_trap = false;
2401 bool maybe_prior_recompile = false;
2402 uint this_trap_count = 0;
2403 if (update_total_trap_count) {
2404 uint idx = reason;
2405 #if INCLUDE_JVMCI
2406 if (is_osr) {
2407 // Upper half of history array used for traps in OSR compilations
2408 idx += Reason_TRAP_HISTORY_LENGTH;
2409 }
2410 #endif
2411 uint prior_trap_count = trap_mdo->trap_count(idx);
2412 this_trap_count = trap_mdo->inc_trap_count(idx);
2413
2414 // If the runtime cannot find a place to store trap history,
2415 // it is estimated based on the general condition of the method.
2416 // If the method has ever been recompiled, or has ever incurred
2417 // a trap with the present reason , then this BCI is assumed
2418 // (pessimistically) to be the culprit.
2419 maybe_prior_trap = (prior_trap_count != 0);
2420 maybe_prior_recompile = (trap_mdo->decompile_count() != 0);
2421 }
2422 ProfileData* pdata = NULL;
2423
2424
2425 // For reasons which are recorded per bytecode, we check per-BCI data.
2426 DeoptReason per_bc_reason = reason_recorded_per_bytecode_if_any(reason);
2427 assert(per_bc_reason != Reason_none || update_total_trap_count, "must be");
2428 if (per_bc_reason != Reason_none) {
2429 // Find the profile data for this BCI. If there isn't one,
2430 // try to allocate one from the MDO's set of spares.
2431 // This will let us detect a repeated trap at this point.
2432 pdata = trap_mdo->allocate_bci_to_data(trap_bci, reason_is_speculate(reason) ? compiled_method : NULL);
2433
2434 if (pdata != NULL) {
2435 if (reason_is_speculate(reason) && !pdata->is_SpeculativeTrapData()) {
2436 if (LogCompilation && xtty != NULL) {
2437 ttyLocker ttyl;
2438 // no more room for speculative traps in this MDO
2439 xtty->elem("speculative_traps_oom");
2440 }
2441 }
2442 // Query the trap state of this profile datum.
2443 int tstate0 = pdata->trap_state();
2444 if (!trap_state_has_reason(tstate0, per_bc_reason))
2445 maybe_prior_trap = false;
2446 if (!trap_state_is_recompiled(tstate0))
2447 maybe_prior_recompile = false;
2448
2449 // Update the trap state of this profile datum.
2450 int tstate1 = tstate0;
2451 // Record the reason.
2452 tstate1 = trap_state_add_reason(tstate1, per_bc_reason);
2453 // Store the updated state on the MDO, for next time.
2454 if (tstate1 != tstate0)
2455 pdata->set_trap_state(tstate1);
2456 } else {
2457 if (LogCompilation && xtty != NULL) {
2458 ttyLocker ttyl;
2459 // Missing MDP? Leave a small complaint in the log.
2460 xtty->elem("missing_mdp bci='%d'", trap_bci);
2461 }
2462 }
2463 }
2464
2465 // Return results:
2466 ret_this_trap_count = this_trap_count;
2467 ret_maybe_prior_trap = maybe_prior_trap;
2468 ret_maybe_prior_recompile = maybe_prior_recompile;
2469 return pdata;
2470 }
2471
2472 void
2473 Deoptimization::update_method_data_from_interpreter(MethodData* trap_mdo, int trap_bci, int reason) {
2474 ResourceMark rm;
2475 // Ignored outputs:
2476 uint ignore_this_trap_count;
2477 bool ignore_maybe_prior_trap;
2478 bool ignore_maybe_prior_recompile;
2479 assert(!reason_is_speculate(reason), "reason speculate only used by compiler");
2480 // JVMCI uses the total counts to determine if deoptimizations are happening too frequently -> do not adjust total counts
2481 bool update_total_counts = true JVMCI_ONLY( && !UseJVMCICompiler);
2482 query_update_method_data(trap_mdo, trap_bci,
2483 (DeoptReason)reason,
2484 update_total_counts,
2485 #if INCLUDE_JVMCI
2486 false,
2487 #endif
2488 NULL,
2489 ignore_this_trap_count,
2490 ignore_maybe_prior_trap,
2491 ignore_maybe_prior_recompile);
2492 }
2493
2494 Deoptimization::UnrollBlock* Deoptimization::uncommon_trap(JavaThread* current, jint trap_request, jint exec_mode) {
2495 // Enable WXWrite: current function is called from methods compiled by C2 directly
2496 MACOS_AARCH64_ONLY(ThreadWXEnable wx(WXWrite, current));
2497
2498 if (TraceDeoptimization) {
2499 tty->print("Uncommon trap ");
2500 }
2501 // Still in Java no safepoints
2502 {
2503 // This enters VM and may safepoint
2504 uncommon_trap_inner(current, trap_request);
2505 }
2506 HandleMark hm(current);
2507 return fetch_unroll_info_helper(current, exec_mode);
2508 }
2509
2510 // Local derived constants.
2511 // Further breakdown of DataLayout::trap_state, as promised by DataLayout.
2512 const int DS_REASON_MASK = ((uint)DataLayout::trap_mask) >> 1;
2513 const int DS_RECOMPILE_BIT = DataLayout::trap_mask - DS_REASON_MASK;
2514
2515 //---------------------------trap_state_reason---------------------------------
2516 Deoptimization::DeoptReason
2517 Deoptimization::trap_state_reason(int trap_state) {
2518 // This assert provides the link between the width of DataLayout::trap_bits
2519 // and the encoding of "recorded" reasons. It ensures there are enough
2520 // bits to store all needed reasons in the per-BCI MDO profile.
2521 assert(DS_REASON_MASK >= Reason_RECORDED_LIMIT, "enough bits");
2522 int recompile_bit = (trap_state & DS_RECOMPILE_BIT);
2523 trap_state -= recompile_bit;
2524 if (trap_state == DS_REASON_MASK) {
2525 return Reason_many;
2526 } else {
2527 assert((int)Reason_none == 0, "state=0 => Reason_none");
2528 return (DeoptReason)trap_state;
2529 }
2530 }
2531 //-------------------------trap_state_has_reason-------------------------------
2532 int Deoptimization::trap_state_has_reason(int trap_state, int reason) {
2533 assert(reason_is_recorded_per_bytecode((DeoptReason)reason), "valid reason");
2534 assert(DS_REASON_MASK >= Reason_RECORDED_LIMIT, "enough bits");
2535 int recompile_bit = (trap_state & DS_RECOMPILE_BIT);
2536 trap_state -= recompile_bit;
2537 if (trap_state == DS_REASON_MASK) {
2538 return -1; // true, unspecifically (bottom of state lattice)
2539 } else if (trap_state == reason) {
2540 return 1; // true, definitely
2541 } else if (trap_state == 0) {
2542 return 0; // false, definitely (top of state lattice)
2543 } else {
2544 return 0; // false, definitely
2545 }
2546 }
2547 //-------------------------trap_state_add_reason-------------------------------
2548 int Deoptimization::trap_state_add_reason(int trap_state, int reason) {
2549 assert(reason_is_recorded_per_bytecode((DeoptReason)reason) || reason == Reason_many, "valid reason");
2550 int recompile_bit = (trap_state & DS_RECOMPILE_BIT);
2551 trap_state -= recompile_bit;
2552 if (trap_state == DS_REASON_MASK) {
2553 return trap_state + recompile_bit; // already at state lattice bottom
2554 } else if (trap_state == reason) {
2555 return trap_state + recompile_bit; // the condition is already true
2556 } else if (trap_state == 0) {
2557 return reason + recompile_bit; // no condition has yet been true
2558 } else {
2559 return DS_REASON_MASK + recompile_bit; // fall to state lattice bottom
2560 }
2561 }
2562 //-----------------------trap_state_is_recompiled------------------------------
2563 bool Deoptimization::trap_state_is_recompiled(int trap_state) {
2564 return (trap_state & DS_RECOMPILE_BIT) != 0;
2565 }
2566 //-----------------------trap_state_set_recompiled-----------------------------
2567 int Deoptimization::trap_state_set_recompiled(int trap_state, bool z) {
2568 if (z) return trap_state | DS_RECOMPILE_BIT;
2569 else return trap_state & ~DS_RECOMPILE_BIT;
2570 }
2571 //---------------------------format_trap_state---------------------------------
2572 // This is used for debugging and diagnostics, including LogFile output.
2573 const char* Deoptimization::format_trap_state(char* buf, size_t buflen,
2574 int trap_state) {
2575 assert(buflen > 0, "sanity");
2576 DeoptReason reason = trap_state_reason(trap_state);
2577 bool recomp_flag = trap_state_is_recompiled(trap_state);
2578 // Re-encode the state from its decoded components.
2579 int decoded_state = 0;
2580 if (reason_is_recorded_per_bytecode(reason) || reason == Reason_many)
2581 decoded_state = trap_state_add_reason(decoded_state, reason);
2582 if (recomp_flag)
2583 decoded_state = trap_state_set_recompiled(decoded_state, recomp_flag);
2584 // If the state re-encodes properly, format it symbolically.
2585 // Because this routine is used for debugging and diagnostics,
2586 // be robust even if the state is a strange value.
2587 size_t len;
2588 if (decoded_state != trap_state) {
2589 // Random buggy state that doesn't decode??
2590 len = jio_snprintf(buf, buflen, "#%d", trap_state);
2591 } else {
2592 len = jio_snprintf(buf, buflen, "%s%s",
2593 trap_reason_name(reason),
2594 recomp_flag ? " recompiled" : "");
2595 }
2596 return buf;
2597 }
2598
2599
2600 //--------------------------------statics--------------------------------------
2601 const char* Deoptimization::_trap_reason_name[] = {
2602 // Note: Keep this in sync. with enum DeoptReason.
2603 "none",
2604 "null_check",
2605 "null_assert" JVMCI_ONLY("_or_unreached0"),
2606 "range_check",
2607 "class_check",
2608 "array_check",
2609 "intrinsic" JVMCI_ONLY("_or_type_checked_inlining"),
2610 "bimorphic" JVMCI_ONLY("_or_optimized_type_check"),
2611 "profile_predicate",
2612 "unloaded",
2613 "uninitialized",
2614 "initialized",
2615 "unreached",
2616 "unhandled",
2617 "constraint",
2618 "div0_check",
2619 "age",
2620 "predicate",
2621 "loop_limit_check",
2622 "speculate_class_check",
2623 "speculate_null_check",
2624 "speculate_null_assert",
2625 "rtm_state_change",
2626 "unstable_if",
2627 "unstable_fused_if",
2628 "receiver_constraint",
2629 #if INCLUDE_JVMCI
2630 "aliasing",
2631 "transfer_to_interpreter",
2632 "not_compiled_exception_handler",
2633 "unresolved",
2634 "jsr_mismatch",
2635 #endif
2636 "tenured"
2637 };
2638 const char* Deoptimization::_trap_action_name[] = {
2639 // Note: Keep this in sync. with enum DeoptAction.
2640 "none",
2641 "maybe_recompile",
2642 "reinterpret",
2643 "make_not_entrant",
2644 "make_not_compilable"
2645 };
2646
2647 const char* Deoptimization::trap_reason_name(int reason) {
2648 // Check that every reason has a name
2649 STATIC_ASSERT(sizeof(_trap_reason_name)/sizeof(const char*) == Reason_LIMIT);
2650
2651 if (reason == Reason_many) return "many";
2652 if ((uint)reason < Reason_LIMIT)
2653 return _trap_reason_name[reason];
2654 static char buf[20];
2655 sprintf(buf, "reason%d", reason);
2656 return buf;
2657 }
2658 const char* Deoptimization::trap_action_name(int action) {
2659 // Check that every action has a name
2660 STATIC_ASSERT(sizeof(_trap_action_name)/sizeof(const char*) == Action_LIMIT);
2661
2662 if ((uint)action < Action_LIMIT)
2663 return _trap_action_name[action];
2664 static char buf[20];
2665 sprintf(buf, "action%d", action);
2666 return buf;
2667 }
2668
2669 // This is used for debugging and diagnostics, including LogFile output.
2670 const char* Deoptimization::format_trap_request(char* buf, size_t buflen,
2671 int trap_request) {
2672 jint unloaded_class_index = trap_request_index(trap_request);
2673 const char* reason = trap_reason_name(trap_request_reason(trap_request));
2674 const char* action = trap_action_name(trap_request_action(trap_request));
2675 #if INCLUDE_JVMCI
2676 int debug_id = trap_request_debug_id(trap_request);
2677 #endif
2678 size_t len;
2679 if (unloaded_class_index < 0) {
2680 len = jio_snprintf(buf, buflen, "reason='%s' action='%s'" JVMCI_ONLY(" debug_id='%d'"),
2681 reason, action
2682 #if INCLUDE_JVMCI
2683 ,debug_id
2684 #endif
2685 );
2686 } else {
2687 len = jio_snprintf(buf, buflen, "reason='%s' action='%s' index='%d'" JVMCI_ONLY(" debug_id='%d'"),
2688 reason, action, unloaded_class_index
2689 #if INCLUDE_JVMCI
2690 ,debug_id
2691 #endif
2692 );
2693 }
2694 return buf;
2695 }
2696
2697 juint Deoptimization::_deoptimization_hist
2698 [Deoptimization::Reason_LIMIT]
2699 [1 + Deoptimization::Action_LIMIT]
2700 [Deoptimization::BC_CASE_LIMIT]
2701 = {0};
2702
2703 enum {
2704 LSB_BITS = 8,
2705 LSB_MASK = right_n_bits(LSB_BITS)
2706 };
2707
2708 void Deoptimization::gather_statistics(DeoptReason reason, DeoptAction action,
2709 Bytecodes::Code bc) {
2710 assert(reason >= 0 && reason < Reason_LIMIT, "oob");
2711 assert(action >= 0 && action < Action_LIMIT, "oob");
2712 _deoptimization_hist[Reason_none][0][0] += 1; // total
2713 _deoptimization_hist[reason][0][0] += 1; // per-reason total
2714 juint* cases = _deoptimization_hist[reason][1+action];
2715 juint* bc_counter_addr = NULL;
2716 juint bc_counter = 0;
2717 // Look for an unused counter, or an exact match to this BC.
2718 if (bc != Bytecodes::_illegal) {
2719 for (int bc_case = 0; bc_case < BC_CASE_LIMIT; bc_case++) {
2720 juint* counter_addr = &cases[bc_case];
2721 juint counter = *counter_addr;
2722 if ((counter == 0 && bc_counter_addr == NULL)
2723 || (Bytecodes::Code)(counter & LSB_MASK) == bc) {
2724 // this counter is either free or is already devoted to this BC
2725 bc_counter_addr = counter_addr;
2726 bc_counter = counter | bc;
2727 }
2728 }
2729 }
2730 if (bc_counter_addr == NULL) {
2731 // Overflow, or no given bytecode.
2732 bc_counter_addr = &cases[BC_CASE_LIMIT-1];
2733 bc_counter = (*bc_counter_addr & ~LSB_MASK); // clear LSB
2734 }
2735 *bc_counter_addr = bc_counter + (1 << LSB_BITS);
2736 }
2737
2738 jint Deoptimization::total_deoptimization_count() {
2739 return _deoptimization_hist[Reason_none][0][0];
2740 }
2741
2742 void Deoptimization::print_statistics() {
2743 juint total = total_deoptimization_count();
2744 juint account = total;
2745 if (total != 0) {
2746 ttyLocker ttyl;
2747 if (xtty != NULL) xtty->head("statistics type='deoptimization'");
2748 tty->print_cr("Deoptimization traps recorded:");
2749 #define PRINT_STAT_LINE(name, r) \
2750 tty->print_cr(" %4d (%4.1f%%) %s", (int)(r), ((r) * 100.0) / total, name);
2751 PRINT_STAT_LINE("total", total);
2752 // For each non-zero entry in the histogram, print the reason,
2753 // the action, and (if specifically known) the type of bytecode.
2754 for (int reason = 0; reason < Reason_LIMIT; reason++) {
2755 for (int action = 0; action < Action_LIMIT; action++) {
2756 juint* cases = _deoptimization_hist[reason][1+action];
2757 for (int bc_case = 0; bc_case < BC_CASE_LIMIT; bc_case++) {
2758 juint counter = cases[bc_case];
2759 if (counter != 0) {
2760 char name[1*K];
2761 Bytecodes::Code bc = (Bytecodes::Code)(counter & LSB_MASK);
2762 if (bc_case == BC_CASE_LIMIT && (int)bc == 0)
2763 bc = Bytecodes::_illegal;
2764 sprintf(name, "%s/%s/%s",
2765 trap_reason_name(reason),
2766 trap_action_name(action),
2767 Bytecodes::is_defined(bc)? Bytecodes::name(bc): "other");
2768 juint r = counter >> LSB_BITS;
2769 tty->print_cr(" %40s: " UINT32_FORMAT " (%.1f%%)", name, r, (r * 100.0) / total);
2770 account -= r;
2771 }
2772 }
2773 }
2774 }
2775 if (account != 0) {
2776 PRINT_STAT_LINE("unaccounted", account);
2777 }
2778 #undef PRINT_STAT_LINE
2779 if (xtty != NULL) xtty->tail("statistics");
2780 }
2781 }
2782
2783 #else // COMPILER2_OR_JVMCI
2784
2785
2786 // Stubs for C1 only system.
2787 bool Deoptimization::trap_state_is_recompiled(int trap_state) {
2788 return false;
2789 }
2790
2791 const char* Deoptimization::trap_reason_name(int reason) {
2792 return "unknown";
2793 }
2794
2795 void Deoptimization::print_statistics() {
2796 // no output
2797 }
2798
2799 void
2800 Deoptimization::update_method_data_from_interpreter(MethodData* trap_mdo, int trap_bci, int reason) {
2801 // no udpate
2802 }
2803
2804 int Deoptimization::trap_state_has_reason(int trap_state, int reason) {
2805 return 0;
2806 }
2807
2808 void Deoptimization::gather_statistics(DeoptReason reason, DeoptAction action,
2809 Bytecodes::Code bc) {
2810 // no update
2811 }
2812
2813 const char* Deoptimization::format_trap_state(char* buf, size_t buflen,
2814 int trap_state) {
2815 jio_snprintf(buf, buflen, "#%d", trap_state);
2816 return buf;
2817 }
2818
2819 #endif // COMPILER2_OR_JVMCI