1 /*
2 * Copyright (c) 1997, 2019, 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/systemDictionary.hpp"
28 #include "code/codeCache.hpp"
29 #include "code/debugInfoRec.hpp"
30 #include "code/nmethod.hpp"
31 #include "code/pcDesc.hpp"
32 #include "code/scopeDesc.hpp"
33 #include "interpreter/bytecode.hpp"
34 #include "interpreter/interpreter.hpp"
35 #include "interpreter/oopMapCache.hpp"
36 #include "memory/allocation.inline.hpp"
37 #include "memory/oopFactory.hpp"
38 #include "memory/resourceArea.hpp"
39 #include "oops/constantPool.hpp"
40 #include "oops/method.hpp"
41 #include "oops/objArrayOop.inline.hpp"
42 #include "oops/oop.inline.hpp"
43 #include "oops/fieldStreams.hpp"
44 #include "oops/typeArrayOop.inline.hpp"
45 #include "oops/verifyOopClosure.hpp"
46 #include "prims/jvmtiThreadState.hpp"
47 #include "runtime/biasedLocking.hpp"
48 #include "runtime/compilationPolicy.hpp"
49 #include "runtime/deoptimization.hpp"
50 #include "runtime/frame.inline.hpp"
51 #include "runtime/handles.inline.hpp"
52 #include "runtime/interfaceSupport.inline.hpp"
53 #include "runtime/safepointVerifiers.hpp"
54 #include "runtime/sharedRuntime.hpp"
55 #include "runtime/signature.hpp"
56 #include "runtime/stubRoutines.hpp"
57 #include "runtime/thread.hpp"
58 #include "runtime/threadSMR.hpp"
59 #include "runtime/vframe.hpp"
60 #include "runtime/vframeArray.hpp"
61 #include "runtime/vframe_hp.hpp"
62 #include "utilities/events.hpp"
63 #include "utilities/preserveException.hpp"
64 #include "utilities/xmlstream.hpp"
65
66
67 bool DeoptimizationMarker::_is_active = false;
68
69 Deoptimization::UnrollBlock::UnrollBlock(int size_of_deoptimized_frame,
70 int caller_adjustment,
71 int caller_actual_parameters,
72 int number_of_frames,
73 intptr_t* frame_sizes,
74 address* frame_pcs,
75 BasicType return_type,
76 int exec_mode) {
77 _size_of_deoptimized_frame = size_of_deoptimized_frame;
78 _caller_adjustment = caller_adjustment;
79 _caller_actual_parameters = caller_actual_parameters;
80 _number_of_frames = number_of_frames;
81 _frame_sizes = frame_sizes;
82 _frame_pcs = frame_pcs;
83 _register_block = NEW_C_HEAP_ARRAY(intptr_t, RegisterMap::reg_count * 2, mtCompiler);
84 _return_type = return_type;
85 _initial_info = 0;
86 // PD (x86 only)
87 _counter_temp = 0;
88 _unpack_kind = exec_mode;
89 _sender_sp_temp = 0;
90
91 _total_frame_sizes = size_of_frames();
92 assert(exec_mode >= 0 && exec_mode < Unpack_LIMIT, "Unexpected exec_mode");
93 }
94
95
96 Deoptimization::UnrollBlock::~UnrollBlock() {
97 FREE_C_HEAP_ARRAY(intptr_t, _frame_sizes);
98 FREE_C_HEAP_ARRAY(intptr_t, _frame_pcs);
99 FREE_C_HEAP_ARRAY(intptr_t, _register_block);
100 }
101
102
103 intptr_t* Deoptimization::UnrollBlock::value_addr_at(int register_number) const {
104 assert(register_number < RegisterMap::reg_count, "checking register number");
105 return &_register_block[register_number * 2];
106 }
107
108
109
110 int Deoptimization::UnrollBlock::size_of_frames() const {
111 // Acount first for the adjustment of the initial frame
112 int result = _caller_adjustment;
113 for (int index = 0; index < number_of_frames(); index++) {
114 result += frame_sizes()[index];
115 }
116 return result;
117 }
118
119
120 void Deoptimization::UnrollBlock::print() {
121 ttyLocker ttyl;
122 tty->print_cr("UnrollBlock");
123 tty->print_cr(" size_of_deoptimized_frame = %d", _size_of_deoptimized_frame);
124 tty->print( " frame_sizes: ");
125 for (int index = 0; index < number_of_frames(); index++) {
126 tty->print(INTX_FORMAT " ", frame_sizes()[index]);
127 }
128 tty->cr();
129 }
130
131
132 // In order to make fetch_unroll_info work properly with escape
133 // analysis, The method was changed from JRT_LEAF to JRT_BLOCK_ENTRY and
134 // ResetNoHandleMark and HandleMark were removed from it. The actual reallocation
135 // of previously eliminated objects occurs in realloc_objects, which is
136 // called from the method fetch_unroll_info_helper below.
137 JRT_BLOCK_ENTRY(Deoptimization::UnrollBlock*, Deoptimization::fetch_unroll_info(JavaThread* thread, int exec_mode))
138 // It is actually ok to allocate handles in a leaf method. It causes no safepoints,
139 // but makes the entry a little slower. There is however a little dance we have to
140 // do in debug mode to get around the NoHandleMark code in the JRT_LEAF macro
141
142 // fetch_unroll_info() is called at the beginning of the deoptimization
143 // handler. Note this fact before we start generating temporary frames
144 // that can confuse an asynchronous stack walker. This counter is
145 // decremented at the end of unpack_frames().
146 if (TraceDeoptimization) {
147 tty->print_cr("Deoptimizing thread " INTPTR_FORMAT, p2i(thread));
148 }
149 thread->inc_in_deopt_handler();
150
151 return fetch_unroll_info_helper(thread, exec_mode);
152 JRT_END
153
154
155 // This is factored, since it is both called from a JRT_LEAF (deoptimization) and a JRT_ENTRY (uncommon_trap)
156 Deoptimization::UnrollBlock* Deoptimization::fetch_unroll_info_helper(JavaThread* thread, int exec_mode) {
157
158 // Note: there is a safepoint safety issue here. No matter whether we enter
159 // via vanilla deopt or uncommon trap we MUST NOT stop at a safepoint once
160 // the vframeArray is created.
161 //
162
163 // Allocate our special deoptimization ResourceMark
164 DeoptResourceMark* dmark = new DeoptResourceMark(thread);
165 assert(thread->deopt_mark() == NULL, "Pending deopt!");
166 thread->set_deopt_mark(dmark);
167
168 frame stub_frame = thread->last_frame(); // Makes stack walkable as side effect
169 RegisterMap map(thread, true);
170 RegisterMap dummy_map(thread, false);
171 // Now get the deoptee with a valid map
172 frame deoptee = stub_frame.sender(&map);
173 // Set the deoptee nmethod
174 assert(thread->deopt_compiled_method() == NULL, "Pending deopt!");
175 CompiledMethod* cm = deoptee.cb()->as_compiled_method_or_null();
176 thread->set_deopt_compiled_method(cm);
177
178 if (VerifyStack) {
179 thread->validate_frame_layout();
180 }
181
182 // Create a growable array of VFrames where each VFrame represents an inlined
183 // Java frame. This storage is allocated with the usual system arena.
184 assert(deoptee.is_compiled_frame(), "Wrong frame type");
185 GrowableArray<compiledVFrame*>* chunk = new GrowableArray<compiledVFrame*>(10);
186 vframe* vf = vframe::new_vframe(&deoptee, &map, thread);
187 while (!vf->is_top()) {
188 assert(vf->is_compiled_frame(), "Wrong frame type");
189 chunk->push(compiledVFrame::cast(vf));
190 vf = vf->sender();
191 }
192 assert(vf->is_compiled_frame(), "Wrong frame type");
193 chunk->push(compiledVFrame::cast(vf));
194
195 bool realloc_failures = false;
196
197 #if COMPILER2_OR_JVMCI
198 // Reallocate the non-escaping objects and restore their fields. Then
199 // relock objects if synchronization on them was eliminated.
200 #if !INCLUDE_JVMCI
201 if (DoEscapeAnalysis || EliminateNestedLocks) {
202 if (EliminateAllocations) {
203 #endif // INCLUDE_JVMCI
204 assert (chunk->at(0)->scope() != NULL,"expect only compiled java frames");
205 GrowableArray<ScopeValue*>* objects = chunk->at(0)->scope()->objects();
206
207 // The flag return_oop() indicates call sites which return oop
208 // in compiled code. Such sites include java method calls,
209 // runtime calls (for example, used to allocate new objects/arrays
210 // on slow code path) and any other calls generated in compiled code.
211 // It is not guaranteed that we can get such information here only
212 // by analyzing bytecode in deoptimized frames. This is why this flag
213 // is set during method compilation (see Compile::Process_OopMap_Node()).
214 // If the previous frame was popped or if we are dispatching an exception,
215 // we don't have an oop result.
216 bool save_oop_result = chunk->at(0)->scope()->return_oop() && !thread->popframe_forcing_deopt_reexecution() && (exec_mode == Unpack_deopt);
217 Handle return_value;
218 if (save_oop_result) {
219 // Reallocation may trigger GC. If deoptimization happened on return from
220 // call which returns oop we need to save it since it is not in oopmap.
221 oop result = deoptee.saved_oop_result(&map);
222 assert(oopDesc::is_oop_or_null(result), "must be oop");
223 return_value = Handle(thread, result);
224 assert(Universe::heap()->is_in_or_null(result), "must be heap pointer");
225 if (TraceDeoptimization) {
226 ttyLocker ttyl;
227 tty->print_cr("SAVED OOP RESULT " INTPTR_FORMAT " in thread " INTPTR_FORMAT, p2i(result), p2i(thread));
228 }
229 }
230 if (objects != NULL) {
231 JRT_BLOCK
232 realloc_failures = realloc_objects(thread, &deoptee, objects, THREAD);
233 JRT_END
234 bool skip_internal = (cm != NULL) && !cm->is_compiled_by_jvmci();
235 reassign_fields(&deoptee, &map, objects, realloc_failures, skip_internal);
236 #ifndef PRODUCT
237 if (TraceDeoptimization) {
238 ttyLocker ttyl;
239 tty->print_cr("REALLOC OBJECTS in thread " INTPTR_FORMAT, p2i(thread));
240 print_objects(objects, realloc_failures);
241 }
242 #endif
243 }
244 if (save_oop_result) {
245 // Restore result.
246 deoptee.set_saved_oop_result(&map, return_value());
247 }
248 #if !INCLUDE_JVMCI
249 }
250 if (EliminateLocks) {
251 #endif // INCLUDE_JVMCI
252 #ifndef PRODUCT
253 bool first = true;
254 #endif
255 for (int i = 0; i < chunk->length(); i++) {
256 compiledVFrame* cvf = chunk->at(i);
257 assert (cvf->scope() != NULL,"expect only compiled java frames");
258 GrowableArray<MonitorInfo*>* monitors = cvf->monitors();
259 if (monitors->is_nonempty()) {
260 relock_objects(monitors, thread, realloc_failures);
261 #ifndef PRODUCT
262 if (PrintDeoptimizationDetails) {
263 ttyLocker ttyl;
264 for (int j = 0; j < monitors->length(); j++) {
265 MonitorInfo* mi = monitors->at(j);
266 if (mi->eliminated()) {
267 if (first) {
268 first = false;
269 tty->print_cr("RELOCK OBJECTS in thread " INTPTR_FORMAT, p2i(thread));
270 }
271 if (mi->owner_is_scalar_replaced()) {
272 Klass* k = java_lang_Class::as_Klass(mi->owner_klass());
273 tty->print_cr(" failed reallocation for klass %s", k->external_name());
274 } else {
275 tty->print_cr(" object <" INTPTR_FORMAT "> locked", p2i(mi->owner()));
276 }
277 }
278 }
279 }
280 #endif // !PRODUCT
281 }
282 }
283 #if !INCLUDE_JVMCI
284 }
285 }
286 #endif // INCLUDE_JVMCI
287 #endif // COMPILER2_OR_JVMCI
288
289 ScopeDesc* trap_scope = chunk->at(0)->scope();
290 Handle exceptionObject;
291 if (trap_scope->rethrow_exception()) {
292 if (PrintDeoptimizationDetails) {
293 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());
294 }
295 GrowableArray<ScopeValue*>* expressions = trap_scope->expressions();
296 guarantee(expressions != NULL && expressions->length() > 0, "must have exception to throw");
297 ScopeValue* topOfStack = expressions->top();
298 exceptionObject = StackValue::create_stack_value(&deoptee, &map, topOfStack)->get_obj();
299 guarantee(exceptionObject() != NULL, "exception oop can not be null");
300 }
301
302 // Ensure that no safepoint is taken after pointers have been stored
303 // in fields of rematerialized objects. If a safepoint occurs from here on
304 // out the java state residing in the vframeArray will be missed.
305 NoSafepointVerifier no_safepoint;
306
307 vframeArray* array = create_vframeArray(thread, deoptee, &map, chunk, realloc_failures);
308 #if COMPILER2_OR_JVMCI
309 if (realloc_failures) {
310 pop_frames_failed_reallocs(thread, array);
311 }
312 #endif
313
314 assert(thread->vframe_array_head() == NULL, "Pending deopt!");
315 thread->set_vframe_array_head(array);
316
317 // Now that the vframeArray has been created if we have any deferred local writes
318 // added by jvmti then we can free up that structure as the data is now in the
319 // vframeArray
320
321 if (thread->deferred_locals() != NULL) {
322 GrowableArray<jvmtiDeferredLocalVariableSet*>* list = thread->deferred_locals();
323 int i = 0;
324 do {
325 // Because of inlining we could have multiple vframes for a single frame
326 // and several of the vframes could have deferred writes. Find them all.
327 if (list->at(i)->id() == array->original().id()) {
328 jvmtiDeferredLocalVariableSet* dlv = list->at(i);
329 list->remove_at(i);
330 // individual jvmtiDeferredLocalVariableSet are CHeapObj's
331 delete dlv;
332 } else {
333 i++;
334 }
335 } while ( i < list->length() );
336 if (list->length() == 0) {
337 thread->set_deferred_locals(NULL);
338 // free the list and elements back to C heap.
339 delete list;
340 }
341
342 }
343
344 // Compute the caller frame based on the sender sp of stub_frame and stored frame sizes info.
345 CodeBlob* cb = stub_frame.cb();
346 // Verify we have the right vframeArray
347 assert(cb->frame_size() >= 0, "Unexpected frame size");
348 intptr_t* unpack_sp = stub_frame.sp() + cb->frame_size();
349
350 // If the deopt call site is a MethodHandle invoke call site we have
351 // to adjust the unpack_sp.
352 nmethod* deoptee_nm = deoptee.cb()->as_nmethod_or_null();
353 if (deoptee_nm != NULL && deoptee_nm->is_method_handle_return(deoptee.pc()))
354 unpack_sp = deoptee.unextended_sp();
355
356 #ifdef ASSERT
357 assert(cb->is_deoptimization_stub() ||
358 cb->is_uncommon_trap_stub() ||
359 strcmp("Stub<DeoptimizationStub.deoptimizationHandler>", cb->name()) == 0 ||
360 strcmp("Stub<UncommonTrapStub.uncommonTrapHandler>", cb->name()) == 0,
361 "unexpected code blob: %s", cb->name());
362 #endif
363
364 // This is a guarantee instead of an assert because if vframe doesn't match
365 // we will unpack the wrong deoptimized frame and wind up in strange places
366 // where it will be very difficult to figure out what went wrong. Better
367 // to die an early death here than some very obscure death later when the
368 // trail is cold.
369 // Note: on ia64 this guarantee can be fooled by frames with no memory stack
370 // in that it will fail to detect a problem when there is one. This needs
371 // more work in tiger timeframe.
372 guarantee(array->unextended_sp() == unpack_sp, "vframe_array_head must contain the vframeArray to unpack");
373
374 int number_of_frames = array->frames();
375
376 // Compute the vframes' sizes. Note that frame_sizes[] entries are ordered from outermost to innermost
377 // virtual activation, which is the reverse of the elements in the vframes array.
378 intptr_t* frame_sizes = NEW_C_HEAP_ARRAY(intptr_t, number_of_frames, mtCompiler);
379 // +1 because we always have an interpreter return address for the final slot.
380 address* frame_pcs = NEW_C_HEAP_ARRAY(address, number_of_frames + 1, mtCompiler);
381 int popframe_extra_args = 0;
382 // Create an interpreter return address for the stub to use as its return
383 // address so the skeletal frames are perfectly walkable
384 frame_pcs[number_of_frames] = Interpreter::deopt_entry(vtos, 0);
385
386 // PopFrame requires that the preserved incoming arguments from the recently-popped topmost
387 // activation be put back on the expression stack of the caller for reexecution
388 if (JvmtiExport::can_pop_frame() && thread->popframe_forcing_deopt_reexecution()) {
389 popframe_extra_args = in_words(thread->popframe_preserved_args_size_in_words());
390 }
391
392 // Find the current pc for sender of the deoptee. Since the sender may have been deoptimized
393 // itself since the deoptee vframeArray was created we must get a fresh value of the pc rather
394 // than simply use array->sender.pc(). This requires us to walk the current set of frames
395 //
396 frame deopt_sender = stub_frame.sender(&dummy_map); // First is the deoptee frame
397 deopt_sender = deopt_sender.sender(&dummy_map); // Now deoptee caller
398
399 // It's possible that the number of parameters at the call site is
400 // different than number of arguments in the callee when method
401 // handles are used. If the caller is interpreted get the real
402 // value so that the proper amount of space can be added to it's
403 // frame.
404 bool caller_was_method_handle = false;
405 if (deopt_sender.is_interpreted_frame()) {
406 methodHandle method = deopt_sender.interpreter_frame_method();
407 Bytecode_invoke cur = Bytecode_invoke_check(method, deopt_sender.interpreter_frame_bci());
408 if (cur.is_invokedynamic() || cur.is_invokehandle()) {
409 // Method handle invokes may involve fairly arbitrary chains of
410 // calls so it's impossible to know how much actual space the
411 // caller has for locals.
412 caller_was_method_handle = true;
413 }
414 }
415
416 //
417 // frame_sizes/frame_pcs[0] oldest frame (int or c2i)
418 // frame_sizes/frame_pcs[1] next oldest frame (int)
419 // frame_sizes/frame_pcs[n] youngest frame (int)
420 //
421 // Now a pc in frame_pcs is actually the return address to the frame's caller (a frame
422 // owns the space for the return address to it's caller). Confusing ain't it.
423 //
424 // The vframe array can address vframes with indices running from
425 // 0.._frames-1. Index 0 is the youngest frame and _frame - 1 is the oldest (root) frame.
426 // When we create the skeletal frames we need the oldest frame to be in the zero slot
427 // in the frame_sizes/frame_pcs so the assembly code can do a trivial walk.
428 // so things look a little strange in this loop.
429 //
430 int callee_parameters = 0;
431 int callee_locals = 0;
432 for (int index = 0; index < array->frames(); index++ ) {
433 // frame[number_of_frames - 1 ] = on_stack_size(youngest)
434 // frame[number_of_frames - 2 ] = on_stack_size(sender(youngest))
435 // frame[number_of_frames - 3 ] = on_stack_size(sender(sender(youngest)))
436 frame_sizes[number_of_frames - 1 - index] = BytesPerWord * array->element(index)->on_stack_size(callee_parameters,
437 callee_locals,
438 index == 0,
439 popframe_extra_args);
440 // This pc doesn't have to be perfect just good enough to identify the frame
441 // as interpreted so the skeleton frame will be walkable
442 // The correct pc will be set when the skeleton frame is completely filled out
443 // The final pc we store in the loop is wrong and will be overwritten below
444 frame_pcs[number_of_frames - 1 - index ] = Interpreter::deopt_entry(vtos, 0) - frame::pc_return_offset;
445
446 callee_parameters = array->element(index)->method()->size_of_parameters();
447 callee_locals = array->element(index)->method()->max_locals();
448 popframe_extra_args = 0;
449 }
450
451 // Compute whether the root vframe returns a float or double value.
452 BasicType return_type;
453 {
454 methodHandle method(thread, array->element(0)->method());
455 Bytecode_invoke invoke = Bytecode_invoke_check(method, array->element(0)->bci());
456 return_type = invoke.is_valid() ? invoke.result_type() : T_ILLEGAL;
457 }
458
459 // Compute information for handling adapters and adjusting the frame size of the caller.
460 int caller_adjustment = 0;
461
462 // Compute the amount the oldest interpreter frame will have to adjust
463 // its caller's stack by. If the caller is a compiled frame then
464 // we pretend that the callee has no parameters so that the
465 // extension counts for the full amount of locals and not just
466 // locals-parms. This is because without a c2i adapter the parm
467 // area as created by the compiled frame will not be usable by
468 // the interpreter. (Depending on the calling convention there
469 // may not even be enough space).
470
471 // QQQ I'd rather see this pushed down into last_frame_adjust
472 // and have it take the sender (aka caller).
473
474 if (deopt_sender.is_compiled_frame() || caller_was_method_handle) {
475 caller_adjustment = last_frame_adjust(0, callee_locals);
476 } else if (callee_locals > callee_parameters) {
477 // The caller frame may need extending to accommodate
478 // non-parameter locals of the first unpacked interpreted frame.
479 // Compute that adjustment.
480 caller_adjustment = last_frame_adjust(callee_parameters, callee_locals);
481 }
482
483 // If the sender is deoptimized the we must retrieve the address of the handler
484 // since the frame will "magically" show the original pc before the deopt
485 // and we'd undo the deopt.
486
487 frame_pcs[0] = deopt_sender.raw_pc();
488
489 assert(CodeCache::find_blob_unsafe(frame_pcs[0]) != NULL, "bad pc");
490
491 #if INCLUDE_JVMCI
492 if (exceptionObject() != NULL) {
493 thread->set_exception_oop(exceptionObject());
494 exec_mode = Unpack_exception;
495 }
496 #endif
497
498 if (thread->frames_to_pop_failed_realloc() > 0 && exec_mode != Unpack_uncommon_trap) {
499 assert(thread->has_pending_exception(), "should have thrown OOME");
500 thread->set_exception_oop(thread->pending_exception());
501 thread->clear_pending_exception();
502 exec_mode = Unpack_exception;
503 }
504
505 #if INCLUDE_JVMCI
506 if (thread->frames_to_pop_failed_realloc() > 0) {
507 thread->set_pending_monitorenter(false);
508 }
509 #endif
510
511 UnrollBlock* info = new UnrollBlock(array->frame_size() * BytesPerWord,
512 caller_adjustment * BytesPerWord,
513 caller_was_method_handle ? 0 : callee_parameters,
514 number_of_frames,
515 frame_sizes,
516 frame_pcs,
517 return_type,
518 exec_mode);
519 // On some platforms, we need a way to pass some platform dependent
520 // information to the unpacking code so the skeletal frames come out
521 // correct (initial fp value, unextended sp, ...)
522 info->set_initial_info((intptr_t) array->sender().initial_deoptimization_info());
523
524 if (array->frames() > 1) {
525 if (VerifyStack && TraceDeoptimization) {
526 ttyLocker ttyl;
527 tty->print_cr("Deoptimizing method containing inlining");
528 }
529 }
530
531 array->set_unroll_block(info);
532 return info;
533 }
534
535 // Called to cleanup deoptimization data structures in normal case
536 // after unpacking to stack and when stack overflow error occurs
537 void Deoptimization::cleanup_deopt_info(JavaThread *thread,
538 vframeArray *array) {
539
540 // Get array if coming from exception
541 if (array == NULL) {
542 array = thread->vframe_array_head();
543 }
544 thread->set_vframe_array_head(NULL);
545
546 // Free the previous UnrollBlock
547 vframeArray* old_array = thread->vframe_array_last();
548 thread->set_vframe_array_last(array);
549
550 if (old_array != NULL) {
551 UnrollBlock* old_info = old_array->unroll_block();
552 old_array->set_unroll_block(NULL);
553 delete old_info;
554 delete old_array;
555 }
556
557 // Deallocate any resource creating in this routine and any ResourceObjs allocated
558 // inside the vframeArray (StackValueCollections)
559
560 delete thread->deopt_mark();
561 thread->set_deopt_mark(NULL);
562 thread->set_deopt_compiled_method(NULL);
563
564
565 if (JvmtiExport::can_pop_frame()) {
566 #ifndef CC_INTERP
567 // Regardless of whether we entered this routine with the pending
568 // popframe condition bit set, we should always clear it now
569 thread->clear_popframe_condition();
570 #else
571 // C++ interpreter will clear has_pending_popframe when it enters
572 // with method_resume. For deopt_resume2 we clear it now.
573 if (thread->popframe_forcing_deopt_reexecution())
574 thread->clear_popframe_condition();
575 #endif /* CC_INTERP */
576 }
577
578 // unpack_frames() is called at the end of the deoptimization handler
579 // and (in C2) at the end of the uncommon trap handler. Note this fact
580 // so that an asynchronous stack walker can work again. This counter is
581 // incremented at the beginning of fetch_unroll_info() and (in C2) at
582 // the beginning of uncommon_trap().
583 thread->dec_in_deopt_handler();
584 }
585
586 // Moved from cpu directories because none of the cpus has callee save values.
587 // If a cpu implements callee save values, move this to deoptimization_<cpu>.cpp.
588 void Deoptimization::unwind_callee_save_values(frame* f, vframeArray* vframe_array) {
589
590 // This code is sort of the equivalent of C2IAdapter::setup_stack_frame back in
591 // the days we had adapter frames. When we deoptimize a situation where a
592 // compiled caller calls a compiled caller will have registers it expects
593 // to survive the call to the callee. If we deoptimize the callee the only
594 // way we can restore these registers is to have the oldest interpreter
595 // frame that we create restore these values. That is what this routine
596 // will accomplish.
597
598 // At the moment we have modified c2 to not have any callee save registers
599 // so this problem does not exist and this routine is just a place holder.
600
601 assert(f->is_interpreted_frame(), "must be interpreted");
602 }
603
604 // Return BasicType of value being returned
605 JRT_LEAF(BasicType, Deoptimization::unpack_frames(JavaThread* thread, int exec_mode))
606
607 // We are already active in the special DeoptResourceMark any ResourceObj's we
608 // allocate will be freed at the end of the routine.
609
610 // It is actually ok to allocate handles in a leaf method. It causes no safepoints,
611 // but makes the entry a little slower. There is however a little dance we have to
612 // do in debug mode to get around the NoHandleMark code in the JRT_LEAF macro
613 ResetNoHandleMark rnhm; // No-op in release/product versions
614 HandleMark hm;
615
616 frame stub_frame = thread->last_frame();
617
618 // Since the frame to unpack is the top frame of this thread, the vframe_array_head
619 // must point to the vframeArray for the unpack frame.
620 vframeArray* array = thread->vframe_array_head();
621
622 #ifndef PRODUCT
623 if (TraceDeoptimization) {
624 ttyLocker ttyl;
625 tty->print_cr("DEOPT UNPACKING thread " INTPTR_FORMAT " vframeArray " INTPTR_FORMAT " mode %d",
626 p2i(thread), p2i(array), exec_mode);
627 }
628 #endif
629 Events::log(thread, "DEOPT UNPACKING pc=" INTPTR_FORMAT " sp=" INTPTR_FORMAT " mode %d",
630 p2i(stub_frame.pc()), p2i(stub_frame.sp()), exec_mode);
631
632 UnrollBlock* info = array->unroll_block();
633
634 // Unpack the interpreter frames and any adapter frame (c2 only) we might create.
635 array->unpack_to_stack(stub_frame, exec_mode, info->caller_actual_parameters());
636
637 BasicType bt = info->return_type();
638
639 // If we have an exception pending, claim that the return type is an oop
640 // so the deopt_blob does not overwrite the exception_oop.
641
642 if (exec_mode == Unpack_exception)
643 bt = T_OBJECT;
644
645 // Cleanup thread deopt data
646 cleanup_deopt_info(thread, array);
647
648 #ifndef PRODUCT
649 if (VerifyStack) {
650 ResourceMark res_mark;
651 // Clear pending exception to not break verification code (restored afterwards)
652 PRESERVE_EXCEPTION_MARK;
653
654 thread->validate_frame_layout();
655
656 // Verify that the just-unpacked frames match the interpreter's
657 // notions of expression stack and locals
658 vframeArray* cur_array = thread->vframe_array_last();
659 RegisterMap rm(thread, false);
660 rm.set_include_argument_oops(false);
661 bool is_top_frame = true;
662 int callee_size_of_parameters = 0;
663 int callee_max_locals = 0;
664 for (int i = 0; i < cur_array->frames(); i++) {
665 vframeArrayElement* el = cur_array->element(i);
666 frame* iframe = el->iframe();
667 guarantee(iframe->is_interpreted_frame(), "Wrong frame type");
668
669 // Get the oop map for this bci
670 InterpreterOopMap mask;
671 int cur_invoke_parameter_size = 0;
672 bool try_next_mask = false;
673 int next_mask_expression_stack_size = -1;
674 int top_frame_expression_stack_adjustment = 0;
675 methodHandle mh(thread, iframe->interpreter_frame_method());
676 OopMapCache::compute_one_oop_map(mh, iframe->interpreter_frame_bci(), &mask);
677 BytecodeStream str(mh);
678 str.set_start(iframe->interpreter_frame_bci());
679 int max_bci = mh->code_size();
680 // Get to the next bytecode if possible
681 assert(str.bci() < max_bci, "bci in interpreter frame out of bounds");
682 // Check to see if we can grab the number of outgoing arguments
683 // at an uncommon trap for an invoke (where the compiler
684 // generates debug info before the invoke has executed)
685 Bytecodes::Code cur_code = str.next();
686 if (Bytecodes::is_invoke(cur_code)) {
687 Bytecode_invoke invoke(mh, iframe->interpreter_frame_bci());
688 cur_invoke_parameter_size = invoke.size_of_parameters();
689 if (i != 0 && !invoke.is_invokedynamic() && MethodHandles::has_member_arg(invoke.klass(), invoke.name())) {
690 callee_size_of_parameters++;
691 }
692 }
693 if (str.bci() < max_bci) {
694 Bytecodes::Code next_code = str.next();
695 if (next_code >= 0) {
696 // The interpreter oop map generator reports results before
697 // the current bytecode has executed except in the case of
698 // calls. It seems to be hard to tell whether the compiler
699 // has emitted debug information matching the "state before"
700 // a given bytecode or the state after, so we try both
701 if (!Bytecodes::is_invoke(cur_code) && cur_code != Bytecodes::_athrow) {
702 // Get expression stack size for the next bytecode
703 InterpreterOopMap next_mask;
704 OopMapCache::compute_one_oop_map(mh, str.bci(), &next_mask);
705 next_mask_expression_stack_size = next_mask.expression_stack_size();
706 if (Bytecodes::is_invoke(next_code)) {
707 Bytecode_invoke invoke(mh, str.bci());
708 next_mask_expression_stack_size += invoke.size_of_parameters();
709 }
710 // Need to subtract off the size of the result type of
711 // the bytecode because this is not described in the
712 // debug info but returned to the interpreter in the TOS
713 // caching register
714 BasicType bytecode_result_type = Bytecodes::result_type(cur_code);
715 if (bytecode_result_type != T_ILLEGAL) {
716 top_frame_expression_stack_adjustment = type2size[bytecode_result_type];
717 }
718 assert(top_frame_expression_stack_adjustment >= 0, "stack adjustment must be positive");
719 try_next_mask = true;
720 }
721 }
722 }
723
724 // Verify stack depth and oops in frame
725 // This assertion may be dependent on the platform we're running on and may need modification (tested on x86 and sparc)
726 if (!(
727 /* SPARC */
728 (iframe->interpreter_frame_expression_stack_size() == mask.expression_stack_size() + callee_size_of_parameters) ||
729 /* x86 */
730 (iframe->interpreter_frame_expression_stack_size() == mask.expression_stack_size() + callee_max_locals) ||
731 (try_next_mask &&
732 (iframe->interpreter_frame_expression_stack_size() == (next_mask_expression_stack_size -
733 top_frame_expression_stack_adjustment))) ||
734 (is_top_frame && (exec_mode == Unpack_exception) && iframe->interpreter_frame_expression_stack_size() == 0) ||
735 (is_top_frame && (exec_mode == Unpack_uncommon_trap || exec_mode == Unpack_reexecute || el->should_reexecute()) &&
736 (iframe->interpreter_frame_expression_stack_size() == mask.expression_stack_size() + cur_invoke_parameter_size))
737 )) {
738 {
739 ttyLocker ttyl;
740
741 // Print out some information that will help us debug the problem
742 tty->print_cr("Wrong number of expression stack elements during deoptimization");
743 tty->print_cr(" Error occurred while verifying frame %d (0..%d, 0 is topmost)", i, cur_array->frames() - 1);
744 tty->print_cr(" Fabricated interpreter frame had %d expression stack elements",
745 iframe->interpreter_frame_expression_stack_size());
746 tty->print_cr(" Interpreter oop map had %d expression stack elements", mask.expression_stack_size());
747 tty->print_cr(" try_next_mask = %d", try_next_mask);
748 tty->print_cr(" next_mask_expression_stack_size = %d", next_mask_expression_stack_size);
749 tty->print_cr(" callee_size_of_parameters = %d", callee_size_of_parameters);
750 tty->print_cr(" callee_max_locals = %d", callee_max_locals);
751 tty->print_cr(" top_frame_expression_stack_adjustment = %d", top_frame_expression_stack_adjustment);
752 tty->print_cr(" exec_mode = %d", exec_mode);
753 tty->print_cr(" cur_invoke_parameter_size = %d", cur_invoke_parameter_size);
754 tty->print_cr(" Thread = " INTPTR_FORMAT ", thread ID = %d", p2i(thread), thread->osthread()->thread_id());
755 tty->print_cr(" Interpreted frames:");
756 for (int k = 0; k < cur_array->frames(); k++) {
757 vframeArrayElement* el = cur_array->element(k);
758 tty->print_cr(" %s (bci %d)", el->method()->name_and_sig_as_C_string(), el->bci());
759 }
760 cur_array->print_on_2(tty);
761 } // release tty lock before calling guarantee
762 guarantee(false, "wrong number of expression stack elements during deopt");
763 }
764 VerifyOopClosure verify;
765 iframe->oops_interpreted_do(&verify, &rm, false);
766 callee_size_of_parameters = mh->size_of_parameters();
767 callee_max_locals = mh->max_locals();
768 is_top_frame = false;
769 }
770 }
771 #endif /* !PRODUCT */
772
773
774 return bt;
775 JRT_END
776
777
778 int Deoptimization::deoptimize_dependents() {
779 Threads::deoptimized_wrt_marked_nmethods();
780 return 0;
781 }
782
783 Deoptimization::DeoptAction Deoptimization::_unloaded_action
784 = Deoptimization::Action_reinterpret;
785
786 #if COMPILER2_OR_JVMCI
787 bool Deoptimization::realloc_objects(JavaThread* thread, frame* fr, GrowableArray<ScopeValue*>* objects, TRAPS) {
788 Handle pending_exception(THREAD, thread->pending_exception());
789 const char* exception_file = thread->exception_file();
790 int exception_line = thread->exception_line();
791 thread->clear_pending_exception();
792
793 bool failures = false;
794
795 for (int i = 0; i < objects->length(); i++) {
796 assert(objects->at(i)->is_object(), "invalid debug information");
797 ObjectValue* sv = (ObjectValue*) objects->at(i);
798
799 Klass* k = java_lang_Class::as_Klass(sv->klass()->as_ConstantOopReadValue()->value()());
800 oop obj = NULL;
801
802 if (k->is_instance_klass()) {
803 InstanceKlass* ik = InstanceKlass::cast(k);
804 obj = ik->allocate_instance(THREAD);
805 } else if (k->is_typeArray_klass()) {
806 TypeArrayKlass* ak = TypeArrayKlass::cast(k);
807 assert(sv->field_size() % type2size[ak->element_type()] == 0, "non-integral array length");
808 int len = sv->field_size() / type2size[ak->element_type()];
809 obj = ak->allocate(len, THREAD);
810 } else if (k->is_objArray_klass()) {
811 ObjArrayKlass* ak = ObjArrayKlass::cast(k);
812 obj = ak->allocate(sv->field_size(), THREAD);
813 }
814
815 if (obj == NULL) {
816 failures = true;
817 }
818
819 assert(sv->value().is_null(), "redundant reallocation");
820 assert(obj != NULL || HAS_PENDING_EXCEPTION, "allocation should succeed or we should get an exception");
821 CLEAR_PENDING_EXCEPTION;
822 sv->set_value(obj);
823 }
824
825 if (failures) {
826 THROW_OOP_(Universe::out_of_memory_error_realloc_objects(), failures);
827 } else if (pending_exception.not_null()) {
828 thread->set_pending_exception(pending_exception(), exception_file, exception_line);
829 }
830
831 return failures;
832 }
833
834 // restore elements of an eliminated type array
835 void Deoptimization::reassign_type_array_elements(frame* fr, RegisterMap* reg_map, ObjectValue* sv, typeArrayOop obj, BasicType type) {
836 int index = 0;
837 intptr_t val;
838
839 for (int i = 0; i < sv->field_size(); i++) {
840 StackValue* value = StackValue::create_stack_value(fr, reg_map, sv->field_at(i));
841 switch(type) {
842 case T_LONG: case T_DOUBLE: {
843 assert(value->type() == T_INT, "Agreement.");
844 StackValue* low =
845 StackValue::create_stack_value(fr, reg_map, sv->field_at(++i));
846 #ifdef _LP64
847 jlong res = (jlong)low->get_int();
848 #else
849 #ifdef SPARC
850 // For SPARC we have to swap high and low words.
851 jlong res = jlong_from((jint)low->get_int(), (jint)value->get_int());
852 #else
853 jlong res = jlong_from((jint)value->get_int(), (jint)low->get_int());
854 #endif //SPARC
855 #endif
856 obj->long_at_put(index, res);
857 break;
858 }
859
860 // Have to cast to INT (32 bits) pointer to avoid little/big-endian problem.
861 case T_INT: case T_FLOAT: { // 4 bytes.
862 assert(value->type() == T_INT, "Agreement.");
863 bool big_value = false;
864 if (i + 1 < sv->field_size() && type == T_INT) {
865 if (sv->field_at(i)->is_location()) {
866 Location::Type type = ((LocationValue*) sv->field_at(i))->location().type();
867 if (type == Location::dbl || type == Location::lng) {
868 big_value = true;
869 }
870 } else if (sv->field_at(i)->is_constant_int()) {
871 ScopeValue* next_scope_field = sv->field_at(i + 1);
872 if (next_scope_field->is_constant_long() || next_scope_field->is_constant_double()) {
873 big_value = true;
874 }
875 }
876 }
877
878 if (big_value) {
879 StackValue* low = StackValue::create_stack_value(fr, reg_map, sv->field_at(++i));
880 #ifdef _LP64
881 jlong res = (jlong)low->get_int();
882 #else
883 #ifdef SPARC
884 // For SPARC we have to swap high and low words.
885 jlong res = jlong_from((jint)low->get_int(), (jint)value->get_int());
886 #else
887 jlong res = jlong_from((jint)value->get_int(), (jint)low->get_int());
888 #endif //SPARC
889 #endif
890 obj->int_at_put(index, (jint)*((jint*)&res));
891 obj->int_at_put(++index, (jint)*(((jint*)&res) + 1));
892 } else {
893 val = value->get_int();
894 obj->int_at_put(index, (jint)*((jint*)&val));
895 }
896 break;
897 }
898
899 case T_SHORT:
900 assert(value->type() == T_INT, "Agreement.");
901 val = value->get_int();
902 obj->short_at_put(index, (jshort)*((jint*)&val));
903 break;
904
905 case T_CHAR:
906 assert(value->type() == T_INT, "Agreement.");
907 val = value->get_int();
908 obj->char_at_put(index, (jchar)*((jint*)&val));
909 break;
910
911 case T_BYTE:
912 assert(value->type() == T_INT, "Agreement.");
913 val = value->get_int();
914 obj->byte_at_put(index, (jbyte)*((jint*)&val));
915 break;
916
917 case T_BOOLEAN:
918 assert(value->type() == T_INT, "Agreement.");
919 val = value->get_int();
920 obj->bool_at_put(index, (jboolean)*((jint*)&val));
921 break;
922
923 default:
924 ShouldNotReachHere();
925 }
926 index++;
927 }
928 }
929
930
931 // restore fields of an eliminated object array
932 void Deoptimization::reassign_object_array_elements(frame* fr, RegisterMap* reg_map, ObjectValue* sv, objArrayOop obj) {
933 for (int i = 0; i < sv->field_size(); i++) {
934 StackValue* value = StackValue::create_stack_value(fr, reg_map, sv->field_at(i));
935 assert(value->type() == T_OBJECT, "object element expected");
936 obj->obj_at_put(i, value->get_obj()());
937 }
938 }
939
940 class ReassignedField {
941 public:
942 int _offset;
943 BasicType _type;
944 public:
945 ReassignedField() {
946 _offset = 0;
947 _type = T_ILLEGAL;
948 }
949 };
950
951 int compare(ReassignedField* left, ReassignedField* right) {
952 return left->_offset - right->_offset;
953 }
954
955 // Restore fields of an eliminated instance object using the same field order
956 // returned by HotSpotResolvedObjectTypeImpl.getInstanceFields(true)
957 static int reassign_fields_by_klass(InstanceKlass* klass, frame* fr, RegisterMap* reg_map, ObjectValue* sv, int svIndex, oop obj, bool skip_internal) {
958 if (klass->superklass() != NULL) {
959 svIndex = reassign_fields_by_klass(klass->superklass(), fr, reg_map, sv, svIndex, obj, skip_internal);
960 }
961
962 GrowableArray<ReassignedField>* fields = new GrowableArray<ReassignedField>();
963 for (AllFieldStream fs(klass); !fs.done(); fs.next()) {
964 if (!fs.access_flags().is_static() && (!skip_internal || !fs.access_flags().is_internal())) {
965 ReassignedField field;
966 field._offset = fs.offset();
967 field._type = FieldType::basic_type(fs.signature());
968 fields->append(field);
969 }
970 }
971 fields->sort(compare);
972 for (int i = 0; i < fields->length(); i++) {
973 intptr_t val;
974 ScopeValue* scope_field = sv->field_at(svIndex);
975 StackValue* value = StackValue::create_stack_value(fr, reg_map, scope_field);
976 int offset = fields->at(i)._offset;
977 BasicType type = fields->at(i)._type;
978 switch (type) {
979 case T_OBJECT: case T_ARRAY:
980 assert(value->type() == T_OBJECT, "Agreement.");
981 obj->obj_field_put(offset, value->get_obj()());
982 break;
983
984 // Have to cast to INT (32 bits) pointer to avoid little/big-endian problem.
985 case T_INT: case T_FLOAT: { // 4 bytes.
986 assert(value->type() == T_INT, "Agreement.");
987 bool big_value = false;
988 if (i+1 < fields->length() && fields->at(i+1)._type == T_INT) {
989 if (scope_field->is_location()) {
990 Location::Type type = ((LocationValue*) scope_field)->location().type();
991 if (type == Location::dbl || type == Location::lng) {
992 big_value = true;
993 }
994 }
995 if (scope_field->is_constant_int()) {
996 ScopeValue* next_scope_field = sv->field_at(svIndex + 1);
997 if (next_scope_field->is_constant_long() || next_scope_field->is_constant_double()) {
998 big_value = true;
999 }
1000 }
1001 }
1002
1003 if (big_value) {
1004 i++;
1005 assert(i < fields->length(), "second T_INT field needed");
1006 assert(fields->at(i)._type == T_INT, "T_INT field needed");
1007 } else {
1008 val = value->get_int();
1009 obj->int_field_put(offset, (jint)*((jint*)&val));
1010 break;
1011 }
1012 }
1013 /* no break */
1014
1015 case T_LONG: case T_DOUBLE: {
1016 assert(value->type() == T_INT, "Agreement.");
1017 StackValue* low = StackValue::create_stack_value(fr, reg_map, sv->field_at(++svIndex));
1018 #ifdef _LP64
1019 jlong res = (jlong)low->get_int();
1020 #else
1021 #ifdef SPARC
1022 // For SPARC we have to swap high and low words.
1023 jlong res = jlong_from((jint)low->get_int(), (jint)value->get_int());
1024 #else
1025 jlong res = jlong_from((jint)value->get_int(), (jint)low->get_int());
1026 #endif //SPARC
1027 #endif
1028 obj->long_field_put(offset, res);
1029 break;
1030 }
1031
1032 case T_SHORT:
1033 assert(value->type() == T_INT, "Agreement.");
1034 val = value->get_int();
1035 obj->short_field_put(offset, (jshort)*((jint*)&val));
1036 break;
1037
1038 case T_CHAR:
1039 assert(value->type() == T_INT, "Agreement.");
1040 val = value->get_int();
1041 obj->char_field_put(offset, (jchar)*((jint*)&val));
1042 break;
1043
1044 case T_BYTE:
1045 assert(value->type() == T_INT, "Agreement.");
1046 val = value->get_int();
1047 obj->byte_field_put(offset, (jbyte)*((jint*)&val));
1048 break;
1049
1050 case T_BOOLEAN:
1051 assert(value->type() == T_INT, "Agreement.");
1052 val = value->get_int();
1053 obj->bool_field_put(offset, (jboolean)*((jint*)&val));
1054 break;
1055
1056 default:
1057 ShouldNotReachHere();
1058 }
1059 svIndex++;
1060 }
1061 return svIndex;
1062 }
1063
1064 // restore fields of all eliminated objects and arrays
1065 void Deoptimization::reassign_fields(frame* fr, RegisterMap* reg_map, GrowableArray<ScopeValue*>* objects, bool realloc_failures, bool skip_internal) {
1066 for (int i = 0; i < objects->length(); i++) {
1067 ObjectValue* sv = (ObjectValue*) objects->at(i);
1068 Klass* k = java_lang_Class::as_Klass(sv->klass()->as_ConstantOopReadValue()->value()());
1069 Handle obj = sv->value();
1070 assert(obj.not_null() || realloc_failures, "reallocation was missed");
1071 if (PrintDeoptimizationDetails) {
1072 tty->print_cr("reassign fields for object of type %s!", k->name()->as_C_string());
1073 }
1074 if (obj.is_null()) {
1075 continue;
1076 }
1077
1078 if (k->is_instance_klass()) {
1079 InstanceKlass* ik = InstanceKlass::cast(k);
1080 reassign_fields_by_klass(ik, fr, reg_map, sv, 0, obj(), skip_internal);
1081 } else if (k->is_typeArray_klass()) {
1082 TypeArrayKlass* ak = TypeArrayKlass::cast(k);
1083 reassign_type_array_elements(fr, reg_map, sv, (typeArrayOop) obj(), ak->element_type());
1084 } else if (k->is_objArray_klass()) {
1085 reassign_object_array_elements(fr, reg_map, sv, (objArrayOop) obj());
1086 }
1087 }
1088 }
1089
1090
1091 // relock objects for which synchronization was eliminated
1092 void Deoptimization::relock_objects(GrowableArray<MonitorInfo*>* monitors, JavaThread* thread, bool realloc_failures) {
1093 for (int i = 0; i < monitors->length(); i++) {
1094 MonitorInfo* mon_info = monitors->at(i);
1095 if (mon_info->eliminated()) {
1096 assert(!mon_info->owner_is_scalar_replaced() || realloc_failures, "reallocation was missed");
1097 if (!mon_info->owner_is_scalar_replaced()) {
1098 Handle obj(thread, mon_info->owner());
1099 markOop mark = obj->mark();
1100 if (UseBiasedLocking && mark->has_bias_pattern()) {
1101 // New allocated objects may have the mark set to anonymously biased.
1102 // Also the deoptimized method may called methods with synchronization
1103 // where the thread-local object is bias locked to the current thread.
1104 assert(mark->is_biased_anonymously() ||
1105 mark->biased_locker() == thread, "should be locked to current thread");
1106 // Reset mark word to unbiased prototype.
1107 markOop unbiased_prototype = markOopDesc::prototype()->set_age(mark->age());
1108 obj->set_mark(unbiased_prototype);
1109 }
1110 BasicLock* lock = mon_info->lock();
1111 ObjectSynchronizer::slow_enter(obj, lock, thread);
1112 assert(mon_info->owner()->is_locked(), "object must be locked now");
1113 }
1114 }
1115 }
1116 }
1117
1118
1119 #ifndef PRODUCT
1120 // print information about reallocated objects
1121 void Deoptimization::print_objects(GrowableArray<ScopeValue*>* objects, bool realloc_failures) {
1122 fieldDescriptor fd;
1123
1124 for (int i = 0; i < objects->length(); i++) {
1125 ObjectValue* sv = (ObjectValue*) objects->at(i);
1126 Klass* k = java_lang_Class::as_Klass(sv->klass()->as_ConstantOopReadValue()->value()());
1127 Handle obj = sv->value();
1128
1129 tty->print(" object <" INTPTR_FORMAT "> of type ", p2i(sv->value()()));
1130 k->print_value();
1131 assert(obj.not_null() || realloc_failures, "reallocation was missed");
1132 if (obj.is_null()) {
1133 tty->print(" allocation failed");
1134 } else {
1135 tty->print(" allocated (%d bytes)", obj->size() * HeapWordSize);
1136 }
1137 tty->cr();
1138
1139 if (Verbose && !obj.is_null()) {
1140 k->oop_print_on(obj(), tty);
1141 }
1142 }
1143 }
1144 #endif
1145 #endif // COMPILER2_OR_JVMCI
1146
1147 vframeArray* Deoptimization::create_vframeArray(JavaThread* thread, frame fr, RegisterMap *reg_map, GrowableArray<compiledVFrame*>* chunk, bool realloc_failures) {
1148 Events::log(thread, "DEOPT PACKING pc=" INTPTR_FORMAT " sp=" INTPTR_FORMAT, p2i(fr.pc()), p2i(fr.sp()));
1149
1150 #ifndef PRODUCT
1151 if (PrintDeoptimizationDetails) {
1152 ttyLocker ttyl;
1153 tty->print("DEOPT PACKING thread " INTPTR_FORMAT " ", p2i(thread));
1154 fr.print_on(tty);
1155 tty->print_cr(" Virtual frames (innermost first):");
1156 for (int index = 0; index < chunk->length(); index++) {
1157 compiledVFrame* vf = chunk->at(index);
1158 tty->print(" %2d - ", index);
1159 vf->print_value();
1160 int bci = chunk->at(index)->raw_bci();
1161 const char* code_name;
1162 if (bci == SynchronizationEntryBCI) {
1163 code_name = "sync entry";
1164 } else {
1165 Bytecodes::Code code = vf->method()->code_at(bci);
1166 code_name = Bytecodes::name(code);
1167 }
1168 tty->print(" - %s", code_name);
1169 tty->print_cr(" @ bci %d ", bci);
1170 if (Verbose) {
1171 vf->print();
1172 tty->cr();
1173 }
1174 }
1175 }
1176 #endif
1177
1178 // Register map for next frame (used for stack crawl). We capture
1179 // the state of the deopt'ing frame's caller. Thus if we need to
1180 // stuff a C2I adapter we can properly fill in the callee-save
1181 // register locations.
1182 frame caller = fr.sender(reg_map);
1183 int frame_size = caller.sp() - fr.sp();
1184
1185 frame sender = caller;
1186
1187 // Since the Java thread being deoptimized will eventually adjust it's own stack,
1188 // the vframeArray containing the unpacking information is allocated in the C heap.
1189 // For Compiler1, the caller of the deoptimized frame is saved for use by unpack_frames().
1190 vframeArray* array = vframeArray::allocate(thread, frame_size, chunk, reg_map, sender, caller, fr, realloc_failures);
1191
1192 // Compare the vframeArray to the collected vframes
1193 assert(array->structural_compare(thread, chunk), "just checking");
1194
1195 #ifndef PRODUCT
1196 if (PrintDeoptimizationDetails) {
1197 ttyLocker ttyl;
1198 tty->print_cr(" Created vframeArray " INTPTR_FORMAT, p2i(array));
1199 }
1200 #endif // PRODUCT
1201
1202 return array;
1203 }
1204
1205 #if COMPILER2_OR_JVMCI
1206 void Deoptimization::pop_frames_failed_reallocs(JavaThread* thread, vframeArray* array) {
1207 // Reallocation of some scalar replaced objects failed. Record
1208 // that we need to pop all the interpreter frames for the
1209 // deoptimized compiled frame.
1210 assert(thread->frames_to_pop_failed_realloc() == 0, "missed frames to pop?");
1211 thread->set_frames_to_pop_failed_realloc(array->frames());
1212 // Unlock all monitors here otherwise the interpreter will see a
1213 // mix of locked and unlocked monitors (because of failed
1214 // reallocations of synchronized objects) and be confused.
1215 for (int i = 0; i < array->frames(); i++) {
1216 MonitorChunk* monitors = array->element(i)->monitors();
1217 if (monitors != NULL) {
1218 for (int j = 0; j < monitors->number_of_monitors(); j++) {
1219 BasicObjectLock* src = monitors->at(j);
1220 if (src->obj() != NULL) {
1221 ObjectSynchronizer::fast_exit(src->obj(), src->lock(), thread);
1222 }
1223 }
1224 array->element(i)->free_monitors(thread);
1225 #ifdef ASSERT
1226 array->element(i)->set_removed_monitors();
1227 #endif
1228 }
1229 }
1230 }
1231 #endif
1232
1233 static void collect_monitors(compiledVFrame* cvf, GrowableArray<Handle>* objects_to_revoke) {
1234 GrowableArray<MonitorInfo*>* monitors = cvf->monitors();
1235 Thread* thread = Thread::current();
1236 for (int i = 0; i < monitors->length(); i++) {
1237 MonitorInfo* mon_info = monitors->at(i);
1238 if (!mon_info->eliminated() && mon_info->owner() != NULL) {
1239 objects_to_revoke->append(Handle(thread, mon_info->owner()));
1240 }
1241 }
1242 }
1243
1244
1245 void Deoptimization::revoke_biases_of_monitors(JavaThread* thread, frame fr, RegisterMap* map) {
1246 if (!UseBiasedLocking) {
1247 return;
1248 }
1249
1250 GrowableArray<Handle>* objects_to_revoke = new GrowableArray<Handle>();
1251
1252 // Unfortunately we don't have a RegisterMap available in most of
1253 // the places we want to call this routine so we need to walk the
1254 // stack again to update the register map.
1255 if (map == NULL || !map->update_map()) {
1256 StackFrameStream sfs(thread, true);
1257 bool found = false;
1258 while (!found && !sfs.is_done()) {
1259 frame* cur = sfs.current();
1260 sfs.next();
1261 found = cur->id() == fr.id();
1262 }
1263 assert(found, "frame to be deoptimized not found on target thread's stack");
1264 map = sfs.register_map();
1265 }
1266
1267 vframe* vf = vframe::new_vframe(&fr, map, thread);
1268 compiledVFrame* cvf = compiledVFrame::cast(vf);
1269 // Revoke monitors' biases in all scopes
1270 while (!cvf->is_top()) {
1271 collect_monitors(cvf, objects_to_revoke);
1272 cvf = compiledVFrame::cast(cvf->sender());
1273 }
1274 collect_monitors(cvf, objects_to_revoke);
1275
1276 if (SafepointSynchronize::is_at_safepoint()) {
1277 BiasedLocking::revoke_at_safepoint(objects_to_revoke);
1278 } else {
1279 BiasedLocking::revoke(objects_to_revoke);
1280 }
1281 }
1282
1283
1284 void Deoptimization::deoptimize_single_frame(JavaThread* thread, frame fr, Deoptimization::DeoptReason reason) {
1285 assert(fr.can_be_deoptimized(), "checking frame type");
1286
1287 gather_statistics(reason, Action_none, Bytecodes::_illegal);
1288
1289 if (LogCompilation && xtty != NULL) {
1290 CompiledMethod* cm = fr.cb()->as_compiled_method_or_null();
1291 assert(cm != NULL, "only compiled methods can deopt");
1292
1293 ttyLocker ttyl;
1294 xtty->begin_head("deoptimized thread='" UINTX_FORMAT "' reason='%s' pc='" INTPTR_FORMAT "'",(uintx)thread->osthread()->thread_id(), trap_reason_name(reason), p2i(fr.pc()));
1295 cm->log_identity(xtty);
1296 xtty->end_head();
1297 for (ScopeDesc* sd = cm->scope_desc_at(fr.pc()); ; sd = sd->sender()) {
1298 xtty->begin_elem("jvms bci='%d'", sd->bci());
1299 xtty->method(sd->method());
1300 xtty->end_elem();
1301 if (sd->is_top()) break;
1302 }
1303 xtty->tail("deoptimized");
1304 }
1305
1306 // Patch the compiled method so that when execution returns to it we will
1307 // deopt the execution state and return to the interpreter.
1308 fr.deoptimize(thread);
1309 }
1310
1311 void Deoptimization::deoptimize(JavaThread* thread, frame fr, RegisterMap *map) {
1312 deoptimize(thread, fr, map, Reason_constraint);
1313 }
1314
1315 void Deoptimization::deoptimize(JavaThread* thread, frame fr, RegisterMap *map, DeoptReason reason) {
1316 // Deoptimize only if the frame comes from compile code.
1317 // Do not deoptimize the frame which is already patched
1318 // during the execution of the loops below.
1319 if (!fr.is_compiled_frame() || fr.is_deoptimized_frame()) {
1320 return;
1321 }
1322 ResourceMark rm;
1323 DeoptimizationMarker dm;
1324 if (UseBiasedLocking) {
1325 revoke_biases_of_monitors(thread, fr, map);
1326 }
1327 deoptimize_single_frame(thread, fr, reason);
1328
1329 }
1330
1331 #if INCLUDE_JVMCI
1332 address Deoptimization::deoptimize_for_missing_exception_handler(CompiledMethod* cm) {
1333 // there is no exception handler for this pc => deoptimize
1334 cm->make_not_entrant();
1335
1336 // Use Deoptimization::deoptimize for all of its side-effects:
1337 // revoking biases of monitors, gathering traps statistics, logging...
1338 // it also patches the return pc but we do not care about that
1339 // since we return a continuation to the deopt_blob below.
1340 JavaThread* thread = JavaThread::current();
1341 RegisterMap reg_map(thread, UseBiasedLocking);
1342 frame runtime_frame = thread->last_frame();
1343 frame caller_frame = runtime_frame.sender(®_map);
1344 assert(caller_frame.cb()->as_compiled_method_or_null() == cm, "expect top frame compiled method");
1345 Deoptimization::deoptimize(thread, caller_frame, ®_map, Deoptimization::Reason_not_compiled_exception_handler);
1346
1347 MethodData* trap_mdo = get_method_data(thread, cm->method(), true);
1348 if (trap_mdo != NULL) {
1349 trap_mdo->inc_trap_count(Deoptimization::Reason_not_compiled_exception_handler);
1350 }
1351
1352 return SharedRuntime::deopt_blob()->unpack_with_exception_in_tls();
1353 }
1354 #endif
1355
1356 void Deoptimization::deoptimize_frame_internal(JavaThread* thread, intptr_t* id, DeoptReason reason) {
1357 assert(thread == Thread::current() || SafepointSynchronize::is_at_safepoint(),
1358 "can only deoptimize other thread at a safepoint");
1359 // Compute frame and register map based on thread and sp.
1360 RegisterMap reg_map(thread, UseBiasedLocking);
1361 frame fr = thread->last_frame();
1362 while (fr.id() != id) {
1363 fr = fr.sender(®_map);
1364 }
1365 deoptimize(thread, fr, ®_map, reason);
1366 }
1367
1368
1369 void Deoptimization::deoptimize_frame(JavaThread* thread, intptr_t* id, DeoptReason reason) {
1370 if (thread == Thread::current()) {
1371 Deoptimization::deoptimize_frame_internal(thread, id, reason);
1372 } else {
1373 VM_DeoptimizeFrame deopt(thread, id, reason);
1374 VMThread::execute(&deopt);
1375 }
1376 }
1377
1378 void Deoptimization::deoptimize_frame(JavaThread* thread, intptr_t* id) {
1379 deoptimize_frame(thread, id, Reason_constraint);
1380 }
1381
1382 // JVMTI PopFrame support
1383 JRT_LEAF(void, Deoptimization::popframe_preserve_args(JavaThread* thread, int bytes_to_save, void* start_address))
1384 {
1385 thread->popframe_preserve_args(in_ByteSize(bytes_to_save), start_address);
1386 }
1387 JRT_END
1388
1389 MethodData*
1390 Deoptimization::get_method_data(JavaThread* thread, const methodHandle& m,
1391 bool create_if_missing) {
1392 Thread* THREAD = thread;
1393 MethodData* mdo = m()->method_data();
1394 if (mdo == NULL && create_if_missing && !HAS_PENDING_EXCEPTION) {
1395 // Build an MDO. Ignore errors like OutOfMemory;
1396 // that simply means we won't have an MDO to update.
1397 Method::build_interpreter_method_data(m, THREAD);
1398 if (HAS_PENDING_EXCEPTION) {
1399 assert((PENDING_EXCEPTION->is_a(SystemDictionary::OutOfMemoryError_klass())), "we expect only an OOM error here");
1400 CLEAR_PENDING_EXCEPTION;
1401 }
1402 mdo = m()->method_data();
1403 }
1404 return mdo;
1405 }
1406
1407 #if COMPILER2_OR_JVMCI
1408 void Deoptimization::load_class_by_index(const constantPoolHandle& constant_pool, int index, TRAPS) {
1409 // in case of an unresolved klass entry, load the class.
1410 if (constant_pool->tag_at(index).is_unresolved_klass()) {
1411 Klass* tk = constant_pool->klass_at_ignore_error(index, CHECK);
1412 return;
1413 }
1414
1415 if (!constant_pool->tag_at(index).is_symbol()) return;
1416
1417 Handle class_loader (THREAD, constant_pool->pool_holder()->class_loader());
1418 Symbol* symbol = constant_pool->symbol_at(index);
1419
1420 // class name?
1421 if (symbol->char_at(0) != '(') {
1422 Handle protection_domain (THREAD, constant_pool->pool_holder()->protection_domain());
1423 SystemDictionary::resolve_or_null(symbol, class_loader, protection_domain, CHECK);
1424 return;
1425 }
1426
1427 // then it must be a signature!
1428 ResourceMark rm(THREAD);
1429 for (SignatureStream ss(symbol); !ss.is_done(); ss.next()) {
1430 if (ss.is_object()) {
1431 Symbol* class_name = ss.as_symbol(CHECK);
1432 Handle protection_domain (THREAD, constant_pool->pool_holder()->protection_domain());
1433 SystemDictionary::resolve_or_null(class_name, class_loader, protection_domain, CHECK);
1434 }
1435 }
1436 }
1437
1438
1439 void Deoptimization::load_class_by_index(const constantPoolHandle& constant_pool, int index) {
1440 EXCEPTION_MARK;
1441 load_class_by_index(constant_pool, index, THREAD);
1442 if (HAS_PENDING_EXCEPTION) {
1443 // Exception happened during classloading. We ignore the exception here, since it
1444 // is going to be rethrown since the current activation is going to be deoptimized and
1445 // the interpreter will re-execute the bytecode.
1446 CLEAR_PENDING_EXCEPTION;
1447 // Class loading called java code which may have caused a stack
1448 // overflow. If the exception was thrown right before the return
1449 // to the runtime the stack is no longer guarded. Reguard the
1450 // stack otherwise if we return to the uncommon trap blob and the
1451 // stack bang causes a stack overflow we crash.
1452 assert(THREAD->is_Java_thread(), "only a java thread can be here");
1453 JavaThread* thread = (JavaThread*)THREAD;
1454 bool guard_pages_enabled = thread->stack_guards_enabled();
1455 if (!guard_pages_enabled) guard_pages_enabled = thread->reguard_stack();
1456 assert(guard_pages_enabled, "stack banging in uncommon trap blob may cause crash");
1457 }
1458 }
1459
1460 JRT_ENTRY(void, Deoptimization::uncommon_trap_inner(JavaThread* thread, jint trap_request)) {
1461 HandleMark hm;
1462
1463 // uncommon_trap() is called at the beginning of the uncommon trap
1464 // handler. Note this fact before we start generating temporary frames
1465 // that can confuse an asynchronous stack walker. This counter is
1466 // decremented at the end of unpack_frames().
1467 thread->inc_in_deopt_handler();
1468
1469 // We need to update the map if we have biased locking.
1470 #if INCLUDE_JVMCI
1471 // JVMCI might need to get an exception from the stack, which in turn requires the register map to be valid
1472 RegisterMap reg_map(thread, true);
1473 #else
1474 RegisterMap reg_map(thread, UseBiasedLocking);
1475 #endif
1476 frame stub_frame = thread->last_frame();
1477 frame fr = stub_frame.sender(®_map);
1478 // Make sure the calling nmethod is not getting deoptimized and removed
1479 // before we are done with it.
1480 nmethodLocker nl(fr.pc());
1481
1482 // Log a message
1483 Events::log(thread, "Uncommon trap: trap_request=" PTR32_FORMAT " fr.pc=" INTPTR_FORMAT " relative=" INTPTR_FORMAT,
1484 trap_request, p2i(fr.pc()), fr.pc() - fr.cb()->code_begin());
1485
1486 {
1487 ResourceMark rm;
1488
1489 // Revoke biases of any monitors in the frame to ensure we can migrate them
1490 revoke_biases_of_monitors(thread, fr, ®_map);
1491
1492 DeoptReason reason = trap_request_reason(trap_request);
1493 DeoptAction action = trap_request_action(trap_request);
1494 #if INCLUDE_JVMCI
1495 int debug_id = trap_request_debug_id(trap_request);
1496 #endif
1497 jint unloaded_class_index = trap_request_index(trap_request); // CP idx or -1
1498
1499 vframe* vf = vframe::new_vframe(&fr, ®_map, thread);
1500 compiledVFrame* cvf = compiledVFrame::cast(vf);
1501
1502 CompiledMethod* nm = cvf->code();
1503
1504 ScopeDesc* trap_scope = cvf->scope();
1505
1506 if (TraceDeoptimization) {
1507 ttyLocker ttyl;
1508 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()
1509 #if INCLUDE_JVMCI
1510 , debug_id
1511 #endif
1512 );
1513 }
1514
1515 methodHandle trap_method = trap_scope->method();
1516 int trap_bci = trap_scope->bci();
1517 #if INCLUDE_JVMCI
1518 jlong speculation = thread->pending_failed_speculation();
1519 if (nm->is_compiled_by_jvmci() && nm->is_nmethod()) { // Exclude AOTed methods
1520 nm->as_nmethod()->update_speculation(thread);
1521 } else {
1522 assert(speculation == 0, "There should not be a speculation for methods compiled by non-JVMCI compilers");
1523 }
1524
1525 if (trap_bci == SynchronizationEntryBCI) {
1526 trap_bci = 0;
1527 thread->set_pending_monitorenter(true);
1528 }
1529
1530 if (reason == Deoptimization::Reason_transfer_to_interpreter) {
1531 thread->set_pending_transfer_to_interpreter(true);
1532 }
1533 #endif
1534
1535 Bytecodes::Code trap_bc = trap_method->java_code_at(trap_bci);
1536 // Record this event in the histogram.
1537 gather_statistics(reason, action, trap_bc);
1538
1539 // Ensure that we can record deopt. history:
1540 // Need MDO to record RTM code generation state.
1541 bool create_if_missing = ProfileTraps || UseCodeAging RTM_OPT_ONLY( || UseRTMLocking );
1542
1543 methodHandle profiled_method;
1544 #if INCLUDE_JVMCI
1545 if (nm->is_compiled_by_jvmci()) {
1546 profiled_method = nm->method();
1547 } else {
1548 profiled_method = trap_method;
1549 }
1550 #else
1551 profiled_method = trap_method;
1552 #endif
1553
1554 MethodData* trap_mdo =
1555 get_method_data(thread, profiled_method, create_if_missing);
1556
1557 // Log a message
1558 Events::log_deopt_message(thread, "Uncommon trap: reason=%s action=%s pc=" INTPTR_FORMAT " method=%s @ %d %s",
1559 trap_reason_name(reason), trap_action_name(action), p2i(fr.pc()),
1560 trap_method->name_and_sig_as_C_string(), trap_bci, nm->compiler_name());
1561
1562 // Print a bunch of diagnostics, if requested.
1563 if (TraceDeoptimization || LogCompilation) {
1564 ResourceMark rm;
1565 ttyLocker ttyl;
1566 char buf[100];
1567 if (xtty != NULL) {
1568 xtty->begin_head("uncommon_trap thread='" UINTX_FORMAT "' %s",
1569 os::current_thread_id(),
1570 format_trap_request(buf, sizeof(buf), trap_request));
1571 #if INCLUDE_JVMCI
1572 if (speculation != 0) {
1573 xtty->print(" speculation='" JLONG_FORMAT "'", speculation);
1574 }
1575 #endif
1576 nm->log_identity(xtty);
1577 }
1578 Symbol* class_name = NULL;
1579 bool unresolved = false;
1580 if (unloaded_class_index >= 0) {
1581 constantPoolHandle constants (THREAD, trap_method->constants());
1582 if (constants->tag_at(unloaded_class_index).is_unresolved_klass()) {
1583 class_name = constants->klass_name_at(unloaded_class_index);
1584 unresolved = true;
1585 if (xtty != NULL)
1586 xtty->print(" unresolved='1'");
1587 } else if (constants->tag_at(unloaded_class_index).is_symbol()) {
1588 class_name = constants->symbol_at(unloaded_class_index);
1589 }
1590 if (xtty != NULL)
1591 xtty->name(class_name);
1592 }
1593 if (xtty != NULL && trap_mdo != NULL && (int)reason < (int)MethodData::_trap_hist_limit) {
1594 // Dump the relevant MDO state.
1595 // This is the deopt count for the current reason, any previous
1596 // reasons or recompiles seen at this point.
1597 int dcnt = trap_mdo->trap_count(reason);
1598 if (dcnt != 0)
1599 xtty->print(" count='%d'", dcnt);
1600 ProfileData* pdata = trap_mdo->bci_to_data(trap_bci);
1601 int dos = (pdata == NULL)? 0: pdata->trap_state();
1602 if (dos != 0) {
1603 xtty->print(" state='%s'", format_trap_state(buf, sizeof(buf), dos));
1604 if (trap_state_is_recompiled(dos)) {
1605 int recnt2 = trap_mdo->overflow_recompile_count();
1606 if (recnt2 != 0)
1607 xtty->print(" recompiles2='%d'", recnt2);
1608 }
1609 }
1610 }
1611 if (xtty != NULL) {
1612 xtty->stamp();
1613 xtty->end_head();
1614 }
1615 if (TraceDeoptimization) { // make noise on the tty
1616 tty->print("Uncommon trap occurred in");
1617 nm->method()->print_short_name(tty);
1618 tty->print(" compiler=%s compile_id=%d", nm->compiler_name(), nm->compile_id());
1619 #if INCLUDE_JVMCI
1620 if (nm->is_nmethod()) {
1621 const char* installed_code_name = nm->as_nmethod()->jvmci_name();
1622 if (installed_code_name != NULL) {
1623 tty->print(" (JVMCI: installed code name=%s) ", installed_code_name);
1624 }
1625 }
1626 #endif
1627 tty->print(" (@" INTPTR_FORMAT ") thread=" UINTX_FORMAT " reason=%s action=%s unloaded_class_index=%d" JVMCI_ONLY(" debug_id=%d"),
1628 p2i(fr.pc()),
1629 os::current_thread_id(),
1630 trap_reason_name(reason),
1631 trap_action_name(action),
1632 unloaded_class_index
1633 #if INCLUDE_JVMCI
1634 , debug_id
1635 #endif
1636 );
1637 if (class_name != NULL) {
1638 tty->print(unresolved ? " unresolved class: " : " symbol: ");
1639 class_name->print_symbol_on(tty);
1640 }
1641 tty->cr();
1642 }
1643 if (xtty != NULL) {
1644 // Log the precise location of the trap.
1645 for (ScopeDesc* sd = trap_scope; ; sd = sd->sender()) {
1646 xtty->begin_elem("jvms bci='%d'", sd->bci());
1647 xtty->method(sd->method());
1648 xtty->end_elem();
1649 if (sd->is_top()) break;
1650 }
1651 xtty->tail("uncommon_trap");
1652 }
1653 }
1654 // (End diagnostic printout.)
1655
1656 // Load class if necessary
1657 if (unloaded_class_index >= 0) {
1658 constantPoolHandle constants(THREAD, trap_method->constants());
1659 load_class_by_index(constants, unloaded_class_index);
1660 }
1661
1662 // Flush the nmethod if necessary and desirable.
1663 //
1664 // We need to avoid situations where we are re-flushing the nmethod
1665 // because of a hot deoptimization site. Repeated flushes at the same
1666 // point need to be detected by the compiler and avoided. If the compiler
1667 // cannot avoid them (or has a bug and "refuses" to avoid them), this
1668 // module must take measures to avoid an infinite cycle of recompilation
1669 // and deoptimization. There are several such measures:
1670 //
1671 // 1. If a recompilation is ordered a second time at some site X
1672 // and for the same reason R, the action is adjusted to 'reinterpret',
1673 // to give the interpreter time to exercise the method more thoroughly.
1674 // If this happens, the method's overflow_recompile_count is incremented.
1675 //
1676 // 2. If the compiler fails to reduce the deoptimization rate, then
1677 // the method's overflow_recompile_count will begin to exceed the set
1678 // limit PerBytecodeRecompilationCutoff. If this happens, the action
1679 // is adjusted to 'make_not_compilable', and the method is abandoned
1680 // to the interpreter. This is a performance hit for hot methods,
1681 // but is better than a disastrous infinite cycle of recompilations.
1682 // (Actually, only the method containing the site X is abandoned.)
1683 //
1684 // 3. In parallel with the previous measures, if the total number of
1685 // recompilations of a method exceeds the much larger set limit
1686 // PerMethodRecompilationCutoff, the method is abandoned.
1687 // This should only happen if the method is very large and has
1688 // many "lukewarm" deoptimizations. The code which enforces this
1689 // limit is elsewhere (class nmethod, class Method).
1690 //
1691 // Note that the per-BCI 'is_recompiled' bit gives the compiler one chance
1692 // to recompile at each bytecode independently of the per-BCI cutoff.
1693 //
1694 // The decision to update code is up to the compiler, and is encoded
1695 // in the Action_xxx code. If the compiler requests Action_none
1696 // no trap state is changed, no compiled code is changed, and the
1697 // computation suffers along in the interpreter.
1698 //
1699 // The other action codes specify various tactics for decompilation
1700 // and recompilation. Action_maybe_recompile is the loosest, and
1701 // allows the compiled code to stay around until enough traps are seen,
1702 // and until the compiler gets around to recompiling the trapping method.
1703 //
1704 // The other actions cause immediate removal of the present code.
1705
1706 // Traps caused by injected profile shouldn't pollute trap counts.
1707 bool injected_profile_trap = trap_method->has_injected_profile() &&
1708 (reason == Reason_intrinsic || reason == Reason_unreached);
1709
1710 bool update_trap_state = (reason != Reason_tenured) && !injected_profile_trap;
1711 bool make_not_entrant = false;
1712 bool make_not_compilable = false;
1713 bool reprofile = false;
1714 switch (action) {
1715 case Action_none:
1716 // Keep the old code.
1717 update_trap_state = false;
1718 break;
1719 case Action_maybe_recompile:
1720 // Do not need to invalidate the present code, but we can
1721 // initiate another
1722 // Start compiler without (necessarily) invalidating the nmethod.
1723 // The system will tolerate the old code, but new code should be
1724 // generated when possible.
1725 break;
1726 case Action_reinterpret:
1727 // Go back into the interpreter for a while, and then consider
1728 // recompiling form scratch.
1729 make_not_entrant = true;
1730 // Reset invocation counter for outer most method.
1731 // This will allow the interpreter to exercise the bytecodes
1732 // for a while before recompiling.
1733 // By contrast, Action_make_not_entrant is immediate.
1734 //
1735 // Note that the compiler will track null_check, null_assert,
1736 // range_check, and class_check events and log them as if they
1737 // had been traps taken from compiled code. This will update
1738 // the MDO trap history so that the next compilation will
1739 // properly detect hot trap sites.
1740 reprofile = true;
1741 break;
1742 case Action_make_not_entrant:
1743 // Request immediate recompilation, and get rid of the old code.
1744 // Make them not entrant, so next time they are called they get
1745 // recompiled. Unloaded classes are loaded now so recompile before next
1746 // time they are called. Same for uninitialized. The interpreter will
1747 // link the missing class, if any.
1748 make_not_entrant = true;
1749 break;
1750 case Action_make_not_compilable:
1751 // Give up on compiling this method at all.
1752 make_not_entrant = true;
1753 make_not_compilable = true;
1754 break;
1755 default:
1756 ShouldNotReachHere();
1757 }
1758
1759 // Setting +ProfileTraps fixes the following, on all platforms:
1760 // 4852688: ProfileInterpreter is off by default for ia64. The result is
1761 // infinite heroic-opt-uncommon-trap/deopt/recompile cycles, since the
1762 // recompile relies on a MethodData* to record heroic opt failures.
1763
1764 // Whether the interpreter is producing MDO data or not, we also need
1765 // to use the MDO to detect hot deoptimization points and control
1766 // aggressive optimization.
1767 bool inc_recompile_count = false;
1768 ProfileData* pdata = NULL;
1769 if (ProfileTraps && !is_client_compilation_mode_vm() && update_trap_state && trap_mdo != NULL) {
1770 assert(trap_mdo == get_method_data(thread, profiled_method, false), "sanity");
1771 uint this_trap_count = 0;
1772 bool maybe_prior_trap = false;
1773 bool maybe_prior_recompile = false;
1774 pdata = query_update_method_data(trap_mdo, trap_bci, reason, true,
1775 #if INCLUDE_JVMCI
1776 nm->is_compiled_by_jvmci() && nm->is_osr_method(),
1777 #endif
1778 nm->method(),
1779 //outputs:
1780 this_trap_count,
1781 maybe_prior_trap,
1782 maybe_prior_recompile);
1783 // Because the interpreter also counts null, div0, range, and class
1784 // checks, these traps from compiled code are double-counted.
1785 // This is harmless; it just means that the PerXTrapLimit values
1786 // are in effect a little smaller than they look.
1787
1788 DeoptReason per_bc_reason = reason_recorded_per_bytecode_if_any(reason);
1789 if (per_bc_reason != Reason_none) {
1790 // Now take action based on the partially known per-BCI history.
1791 if (maybe_prior_trap
1792 && this_trap_count >= (uint)PerBytecodeTrapLimit) {
1793 // If there are too many traps at this BCI, force a recompile.
1794 // This will allow the compiler to see the limit overflow, and
1795 // take corrective action, if possible. The compiler generally
1796 // does not use the exact PerBytecodeTrapLimit value, but instead
1797 // changes its tactics if it sees any traps at all. This provides
1798 // a little hysteresis, delaying a recompile until a trap happens
1799 // several times.
1800 //
1801 // Actually, since there is only one bit of counter per BCI,
1802 // the possible per-BCI counts are {0,1,(per-method count)}.
1803 // This produces accurate results if in fact there is only
1804 // one hot trap site, but begins to get fuzzy if there are
1805 // many sites. For example, if there are ten sites each
1806 // trapping two or more times, they each get the blame for
1807 // all of their traps.
1808 make_not_entrant = true;
1809 }
1810
1811 // Detect repeated recompilation at the same BCI, and enforce a limit.
1812 if (make_not_entrant && maybe_prior_recompile) {
1813 // More than one recompile at this point.
1814 inc_recompile_count = maybe_prior_trap;
1815 }
1816 } else {
1817 // For reasons which are not recorded per-bytecode, we simply
1818 // force recompiles unconditionally.
1819 // (Note that PerMethodRecompilationCutoff is enforced elsewhere.)
1820 make_not_entrant = true;
1821 }
1822
1823 // Go back to the compiler if there are too many traps in this method.
1824 if (this_trap_count >= per_method_trap_limit(reason)) {
1825 // If there are too many traps in this method, force a recompile.
1826 // This will allow the compiler to see the limit overflow, and
1827 // take corrective action, if possible.
1828 // (This condition is an unlikely backstop only, because the
1829 // PerBytecodeTrapLimit is more likely to take effect first,
1830 // if it is applicable.)
1831 make_not_entrant = true;
1832 }
1833
1834 // Here's more hysteresis: If there has been a recompile at
1835 // this trap point already, run the method in the interpreter
1836 // for a while to exercise it more thoroughly.
1837 if (make_not_entrant && maybe_prior_recompile && maybe_prior_trap) {
1838 reprofile = true;
1839 }
1840 }
1841
1842 // Take requested actions on the method:
1843
1844 // Recompile
1845 if (make_not_entrant) {
1846 if (!nm->make_not_entrant()) {
1847 return; // the call did not change nmethod's state
1848 }
1849
1850 if (pdata != NULL) {
1851 // Record the recompilation event, if any.
1852 int tstate0 = pdata->trap_state();
1853 int tstate1 = trap_state_set_recompiled(tstate0, true);
1854 if (tstate1 != tstate0)
1855 pdata->set_trap_state(tstate1);
1856 }
1857
1858 #if INCLUDE_RTM_OPT
1859 // Restart collecting RTM locking abort statistic if the method
1860 // is recompiled for a reason other than RTM state change.
1861 // Assume that in new recompiled code the statistic could be different,
1862 // for example, due to different inlining.
1863 if ((reason != Reason_rtm_state_change) && (trap_mdo != NULL) &&
1864 UseRTMDeopt && (nm->as_nmethod()->rtm_state() != ProfileRTM)) {
1865 trap_mdo->atomic_set_rtm_state(ProfileRTM);
1866 }
1867 #endif
1868 // For code aging we count traps separately here, using make_not_entrant()
1869 // as a guard against simultaneous deopts in multiple threads.
1870 if (reason == Reason_tenured && trap_mdo != NULL) {
1871 trap_mdo->inc_tenure_traps();
1872 }
1873 }
1874
1875 if (inc_recompile_count) {
1876 trap_mdo->inc_overflow_recompile_count();
1877 if ((uint)trap_mdo->overflow_recompile_count() >
1878 (uint)PerBytecodeRecompilationCutoff) {
1879 // Give up on the method containing the bad BCI.
1880 if (trap_method() == nm->method()) {
1881 make_not_compilable = true;
1882 } else {
1883 trap_method->set_not_compilable(CompLevel_full_optimization, true, "overflow_recompile_count > PerBytecodeRecompilationCutoff");
1884 // But give grace to the enclosing nm->method().
1885 }
1886 }
1887 }
1888
1889 // Reprofile
1890 if (reprofile) {
1891 CompilationPolicy::policy()->reprofile(trap_scope, nm->is_osr_method());
1892 }
1893
1894 // Give up compiling
1895 if (make_not_compilable && !nm->method()->is_not_compilable(CompLevel_full_optimization)) {
1896 assert(make_not_entrant, "consistent");
1897 nm->method()->set_not_compilable(CompLevel_full_optimization);
1898 }
1899
1900 } // Free marked resources
1901
1902 }
1903 JRT_END
1904
1905 ProfileData*
1906 Deoptimization::query_update_method_data(MethodData* trap_mdo,
1907 int trap_bci,
1908 Deoptimization::DeoptReason reason,
1909 bool update_total_trap_count,
1910 #if INCLUDE_JVMCI
1911 bool is_osr,
1912 #endif
1913 Method* compiled_method,
1914 //outputs:
1915 uint& ret_this_trap_count,
1916 bool& ret_maybe_prior_trap,
1917 bool& ret_maybe_prior_recompile) {
1918 bool maybe_prior_trap = false;
1919 bool maybe_prior_recompile = false;
1920 uint this_trap_count = 0;
1921 if (update_total_trap_count) {
1922 uint idx = reason;
1923 #if INCLUDE_JVMCI
1924 if (is_osr) {
1925 idx += Reason_LIMIT;
1926 }
1927 #endif
1928 uint prior_trap_count = trap_mdo->trap_count(idx);
1929 this_trap_count = trap_mdo->inc_trap_count(idx);
1930
1931 // If the runtime cannot find a place to store trap history,
1932 // it is estimated based on the general condition of the method.
1933 // If the method has ever been recompiled, or has ever incurred
1934 // a trap with the present reason , then this BCI is assumed
1935 // (pessimistically) to be the culprit.
1936 maybe_prior_trap = (prior_trap_count != 0);
1937 maybe_prior_recompile = (trap_mdo->decompile_count() != 0);
1938 }
1939 ProfileData* pdata = NULL;
1940
1941
1942 // For reasons which are recorded per bytecode, we check per-BCI data.
1943 DeoptReason per_bc_reason = reason_recorded_per_bytecode_if_any(reason);
1944 assert(per_bc_reason != Reason_none || update_total_trap_count, "must be");
1945 if (per_bc_reason != Reason_none) {
1946 // Find the profile data for this BCI. If there isn't one,
1947 // try to allocate one from the MDO's set of spares.
1948 // This will let us detect a repeated trap at this point.
1949 pdata = trap_mdo->allocate_bci_to_data(trap_bci, reason_is_speculate(reason) ? compiled_method : NULL);
1950
1951 if (pdata != NULL) {
1952 if (reason_is_speculate(reason) && !pdata->is_SpeculativeTrapData()) {
1953 if (LogCompilation && xtty != NULL) {
1954 ttyLocker ttyl;
1955 // no more room for speculative traps in this MDO
1956 xtty->elem("speculative_traps_oom");
1957 }
1958 }
1959 // Query the trap state of this profile datum.
1960 int tstate0 = pdata->trap_state();
1961 if (!trap_state_has_reason(tstate0, per_bc_reason))
1962 maybe_prior_trap = false;
1963 if (!trap_state_is_recompiled(tstate0))
1964 maybe_prior_recompile = false;
1965
1966 // Update the trap state of this profile datum.
1967 int tstate1 = tstate0;
1968 // Record the reason.
1969 tstate1 = trap_state_add_reason(tstate1, per_bc_reason);
1970 // Store the updated state on the MDO, for next time.
1971 if (tstate1 != tstate0)
1972 pdata->set_trap_state(tstate1);
1973 } else {
1974 if (LogCompilation && xtty != NULL) {
1975 ttyLocker ttyl;
1976 // Missing MDP? Leave a small complaint in the log.
1977 xtty->elem("missing_mdp bci='%d'", trap_bci);
1978 }
1979 }
1980 }
1981
1982 // Return results:
1983 ret_this_trap_count = this_trap_count;
1984 ret_maybe_prior_trap = maybe_prior_trap;
1985 ret_maybe_prior_recompile = maybe_prior_recompile;
1986 return pdata;
1987 }
1988
1989 void
1990 Deoptimization::update_method_data_from_interpreter(MethodData* trap_mdo, int trap_bci, int reason) {
1991 ResourceMark rm;
1992 // Ignored outputs:
1993 uint ignore_this_trap_count;
1994 bool ignore_maybe_prior_trap;
1995 bool ignore_maybe_prior_recompile;
1996 assert(!reason_is_speculate(reason), "reason speculate only used by compiler");
1997 // JVMCI uses the total counts to determine if deoptimizations are happening too frequently -> do not adjust total counts
1998 bool update_total_counts = true JVMCI_ONLY( && !UseJVMCICompiler);
1999 query_update_method_data(trap_mdo, trap_bci,
2000 (DeoptReason)reason,
2001 update_total_counts,
2002 #if INCLUDE_JVMCI
2003 false,
2004 #endif
2005 NULL,
2006 ignore_this_trap_count,
2007 ignore_maybe_prior_trap,
2008 ignore_maybe_prior_recompile);
2009 }
2010
2011 Deoptimization::UnrollBlock* Deoptimization::uncommon_trap(JavaThread* thread, jint trap_request, jint exec_mode) {
2012 if (TraceDeoptimization) {
2013 tty->print("Uncommon trap ");
2014 }
2015 // Still in Java no safepoints
2016 {
2017 // This enters VM and may safepoint
2018 uncommon_trap_inner(thread, trap_request);
2019 }
2020 return fetch_unroll_info_helper(thread, exec_mode);
2021 }
2022
2023 // Local derived constants.
2024 // Further breakdown of DataLayout::trap_state, as promised by DataLayout.
2025 const int DS_REASON_MASK = ((uint)DataLayout::trap_mask) >> 1;
2026 const int DS_RECOMPILE_BIT = DataLayout::trap_mask - DS_REASON_MASK;
2027
2028 //---------------------------trap_state_reason---------------------------------
2029 Deoptimization::DeoptReason
2030 Deoptimization::trap_state_reason(int trap_state) {
2031 // This assert provides the link between the width of DataLayout::trap_bits
2032 // and the encoding of "recorded" reasons. It ensures there are enough
2033 // bits to store all needed reasons in the per-BCI MDO profile.
2034 assert(DS_REASON_MASK >= Reason_RECORDED_LIMIT, "enough bits");
2035 int recompile_bit = (trap_state & DS_RECOMPILE_BIT);
2036 trap_state -= recompile_bit;
2037 if (trap_state == DS_REASON_MASK) {
2038 return Reason_many;
2039 } else {
2040 assert((int)Reason_none == 0, "state=0 => Reason_none");
2041 return (DeoptReason)trap_state;
2042 }
2043 }
2044 //-------------------------trap_state_has_reason-------------------------------
2045 int Deoptimization::trap_state_has_reason(int trap_state, int reason) {
2046 assert(reason_is_recorded_per_bytecode((DeoptReason)reason), "valid reason");
2047 assert(DS_REASON_MASK >= Reason_RECORDED_LIMIT, "enough bits");
2048 int recompile_bit = (trap_state & DS_RECOMPILE_BIT);
2049 trap_state -= recompile_bit;
2050 if (trap_state == DS_REASON_MASK) {
2051 return -1; // true, unspecifically (bottom of state lattice)
2052 } else if (trap_state == reason) {
2053 return 1; // true, definitely
2054 } else if (trap_state == 0) {
2055 return 0; // false, definitely (top of state lattice)
2056 } else {
2057 return 0; // false, definitely
2058 }
2059 }
2060 //-------------------------trap_state_add_reason-------------------------------
2061 int Deoptimization::trap_state_add_reason(int trap_state, int reason) {
2062 assert(reason_is_recorded_per_bytecode((DeoptReason)reason) || reason == Reason_many, "valid reason");
2063 int recompile_bit = (trap_state & DS_RECOMPILE_BIT);
2064 trap_state -= recompile_bit;
2065 if (trap_state == DS_REASON_MASK) {
2066 return trap_state + recompile_bit; // already at state lattice bottom
2067 } else if (trap_state == reason) {
2068 return trap_state + recompile_bit; // the condition is already true
2069 } else if (trap_state == 0) {
2070 return reason + recompile_bit; // no condition has yet been true
2071 } else {
2072 return DS_REASON_MASK + recompile_bit; // fall to state lattice bottom
2073 }
2074 }
2075 //-----------------------trap_state_is_recompiled------------------------------
2076 bool Deoptimization::trap_state_is_recompiled(int trap_state) {
2077 return (trap_state & DS_RECOMPILE_BIT) != 0;
2078 }
2079 //-----------------------trap_state_set_recompiled-----------------------------
2080 int Deoptimization::trap_state_set_recompiled(int trap_state, bool z) {
2081 if (z) return trap_state | DS_RECOMPILE_BIT;
2082 else return trap_state & ~DS_RECOMPILE_BIT;
2083 }
2084 //---------------------------format_trap_state---------------------------------
2085 // This is used for debugging and diagnostics, including LogFile output.
2086 const char* Deoptimization::format_trap_state(char* buf, size_t buflen,
2087 int trap_state) {
2088 assert(buflen > 0, "sanity");
2089 DeoptReason reason = trap_state_reason(trap_state);
2090 bool recomp_flag = trap_state_is_recompiled(trap_state);
2091 // Re-encode the state from its decoded components.
2092 int decoded_state = 0;
2093 if (reason_is_recorded_per_bytecode(reason) || reason == Reason_many)
2094 decoded_state = trap_state_add_reason(decoded_state, reason);
2095 if (recomp_flag)
2096 decoded_state = trap_state_set_recompiled(decoded_state, recomp_flag);
2097 // If the state re-encodes properly, format it symbolically.
2098 // Because this routine is used for debugging and diagnostics,
2099 // be robust even if the state is a strange value.
2100 size_t len;
2101 if (decoded_state != trap_state) {
2102 // Random buggy state that doesn't decode??
2103 len = jio_snprintf(buf, buflen, "#%d", trap_state);
2104 } else {
2105 len = jio_snprintf(buf, buflen, "%s%s",
2106 trap_reason_name(reason),
2107 recomp_flag ? " recompiled" : "");
2108 }
2109 return buf;
2110 }
2111
2112
2113 //--------------------------------statics--------------------------------------
2114 const char* Deoptimization::_trap_reason_name[] = {
2115 // Note: Keep this in sync. with enum DeoptReason.
2116 "none",
2117 "null_check",
2118 "null_assert" JVMCI_ONLY("_or_unreached0"),
2119 "range_check",
2120 "class_check",
2121 "array_check",
2122 "intrinsic" JVMCI_ONLY("_or_type_checked_inlining"),
2123 "bimorphic" JVMCI_ONLY("_or_optimized_type_check"),
2124 "profile_predicate",
2125 "unloaded",
2126 "uninitialized",
2127 "unreached",
2128 "unhandled",
2129 "constraint",
2130 "div0_check",
2131 "age",
2132 "predicate",
2133 "loop_limit_check",
2134 "speculate_class_check",
2135 "speculate_null_check",
2136 "speculate_null_assert",
2137 "rtm_state_change",
2138 "unstable_if",
2139 "unstable_fused_if",
2140 #if INCLUDE_JVMCI
2141 "aliasing",
2142 "transfer_to_interpreter",
2143 "not_compiled_exception_handler",
2144 "unresolved",
2145 "jsr_mismatch",
2146 #endif
2147 "tenured"
2148 };
2149 const char* Deoptimization::_trap_action_name[] = {
2150 // Note: Keep this in sync. with enum DeoptAction.
2151 "none",
2152 "maybe_recompile",
2153 "reinterpret",
2154 "make_not_entrant",
2155 "make_not_compilable"
2156 };
2157
2158 const char* Deoptimization::trap_reason_name(int reason) {
2159 // Check that every reason has a name
2160 STATIC_ASSERT(sizeof(_trap_reason_name)/sizeof(const char*) == Reason_LIMIT);
2161
2162 if (reason == Reason_many) return "many";
2163 if ((uint)reason < Reason_LIMIT)
2164 return _trap_reason_name[reason];
2165 static char buf[20];
2166 sprintf(buf, "reason%d", reason);
2167 return buf;
2168 }
2169 const char* Deoptimization::trap_action_name(int action) {
2170 // Check that every action has a name
2171 STATIC_ASSERT(sizeof(_trap_action_name)/sizeof(const char*) == Action_LIMIT);
2172
2173 if ((uint)action < Action_LIMIT)
2174 return _trap_action_name[action];
2175 static char buf[20];
2176 sprintf(buf, "action%d", action);
2177 return buf;
2178 }
2179
2180 // This is used for debugging and diagnostics, including LogFile output.
2181 const char* Deoptimization::format_trap_request(char* buf, size_t buflen,
2182 int trap_request) {
2183 jint unloaded_class_index = trap_request_index(trap_request);
2184 const char* reason = trap_reason_name(trap_request_reason(trap_request));
2185 const char* action = trap_action_name(trap_request_action(trap_request));
2186 #if INCLUDE_JVMCI
2187 int debug_id = trap_request_debug_id(trap_request);
2188 #endif
2189 size_t len;
2190 if (unloaded_class_index < 0) {
2191 len = jio_snprintf(buf, buflen, "reason='%s' action='%s'" JVMCI_ONLY(" debug_id='%d'"),
2192 reason, action
2193 #if INCLUDE_JVMCI
2194 ,debug_id
2195 #endif
2196 );
2197 } else {
2198 len = jio_snprintf(buf, buflen, "reason='%s' action='%s' index='%d'" JVMCI_ONLY(" debug_id='%d'"),
2199 reason, action, unloaded_class_index
2200 #if INCLUDE_JVMCI
2201 ,debug_id
2202 #endif
2203 );
2204 }
2205 return buf;
2206 }
2207
2208 juint Deoptimization::_deoptimization_hist
2209 [Deoptimization::Reason_LIMIT]
2210 [1 + Deoptimization::Action_LIMIT]
2211 [Deoptimization::BC_CASE_LIMIT]
2212 = {0};
2213
2214 enum {
2215 LSB_BITS = 8,
2216 LSB_MASK = right_n_bits(LSB_BITS)
2217 };
2218
2219 void Deoptimization::gather_statistics(DeoptReason reason, DeoptAction action,
2220 Bytecodes::Code bc) {
2221 assert(reason >= 0 && reason < Reason_LIMIT, "oob");
2222 assert(action >= 0 && action < Action_LIMIT, "oob");
2223 _deoptimization_hist[Reason_none][0][0] += 1; // total
2224 _deoptimization_hist[reason][0][0] += 1; // per-reason total
2225 juint* cases = _deoptimization_hist[reason][1+action];
2226 juint* bc_counter_addr = NULL;
2227 juint bc_counter = 0;
2228 // Look for an unused counter, or an exact match to this BC.
2229 if (bc != Bytecodes::_illegal) {
2230 for (int bc_case = 0; bc_case < BC_CASE_LIMIT; bc_case++) {
2231 juint* counter_addr = &cases[bc_case];
2232 juint counter = *counter_addr;
2233 if ((counter == 0 && bc_counter_addr == NULL)
2234 || (Bytecodes::Code)(counter & LSB_MASK) == bc) {
2235 // this counter is either free or is already devoted to this BC
2236 bc_counter_addr = counter_addr;
2237 bc_counter = counter | bc;
2238 }
2239 }
2240 }
2241 if (bc_counter_addr == NULL) {
2242 // Overflow, or no given bytecode.
2243 bc_counter_addr = &cases[BC_CASE_LIMIT-1];
2244 bc_counter = (*bc_counter_addr & ~LSB_MASK); // clear LSB
2245 }
2246 *bc_counter_addr = bc_counter + (1 << LSB_BITS);
2247 }
2248
2249 jint Deoptimization::total_deoptimization_count() {
2250 return _deoptimization_hist[Reason_none][0][0];
2251 }
2252
2253 void Deoptimization::print_statistics() {
2254 juint total = total_deoptimization_count();
2255 juint account = total;
2256 if (total != 0) {
2257 ttyLocker ttyl;
2258 if (xtty != NULL) xtty->head("statistics type='deoptimization'");
2259 tty->print_cr("Deoptimization traps recorded:");
2260 #define PRINT_STAT_LINE(name, r) \
2261 tty->print_cr(" %4d (%4.1f%%) %s", (int)(r), ((r) * 100.0) / total, name);
2262 PRINT_STAT_LINE("total", total);
2263 // For each non-zero entry in the histogram, print the reason,
2264 // the action, and (if specifically known) the type of bytecode.
2265 for (int reason = 0; reason < Reason_LIMIT; reason++) {
2266 for (int action = 0; action < Action_LIMIT; action++) {
2267 juint* cases = _deoptimization_hist[reason][1+action];
2268 for (int bc_case = 0; bc_case < BC_CASE_LIMIT; bc_case++) {
2269 juint counter = cases[bc_case];
2270 if (counter != 0) {
2271 char name[1*K];
2272 Bytecodes::Code bc = (Bytecodes::Code)(counter & LSB_MASK);
2273 if (bc_case == BC_CASE_LIMIT && (int)bc == 0)
2274 bc = Bytecodes::_illegal;
2275 sprintf(name, "%s/%s/%s",
2276 trap_reason_name(reason),
2277 trap_action_name(action),
2278 Bytecodes::is_defined(bc)? Bytecodes::name(bc): "other");
2279 juint r = counter >> LSB_BITS;
2280 tty->print_cr(" %40s: " UINT32_FORMAT " (%.1f%%)", name, r, (r * 100.0) / total);
2281 account -= r;
2282 }
2283 }
2284 }
2285 }
2286 if (account != 0) {
2287 PRINT_STAT_LINE("unaccounted", account);
2288 }
2289 #undef PRINT_STAT_LINE
2290 if (xtty != NULL) xtty->tail("statistics");
2291 }
2292 }
2293 #else // COMPILER2_OR_JVMCI
2294
2295
2296 // Stubs for C1 only system.
2297 bool Deoptimization::trap_state_is_recompiled(int trap_state) {
2298 return false;
2299 }
2300
2301 const char* Deoptimization::trap_reason_name(int reason) {
2302 return "unknown";
2303 }
2304
2305 void Deoptimization::print_statistics() {
2306 // no output
2307 }
2308
2309 void
2310 Deoptimization::update_method_data_from_interpreter(MethodData* trap_mdo, int trap_bci, int reason) {
2311 // no udpate
2312 }
2313
2314 int Deoptimization::trap_state_has_reason(int trap_state, int reason) {
2315 return 0;
2316 }
2317
2318 void Deoptimization::gather_statistics(DeoptReason reason, DeoptAction action,
2319 Bytecodes::Code bc) {
2320 // no update
2321 }
2322
2323 const char* Deoptimization::format_trap_state(char* buf, size_t buflen,
2324 int trap_state) {
2325 jio_snprintf(buf, buflen, "#%d", trap_state);
2326 return buf;
2327 }
2328
2329 #endif // COMPILER2_OR_JVMCI