1 /*
2 * Copyright (c) 1997, 2017, 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/method.hpp"
40 #include "oops/objArrayOop.inline.hpp"
41 #include "oops/oop.inline.hpp"
42 #include "oops/fieldStreams.hpp"
43 #include "oops/verifyOopClosure.hpp"
44 #include "prims/jvmtiThreadState.hpp"
45 #include "runtime/biasedLocking.hpp"
46 #include "runtime/compilationPolicy.hpp"
47 #include "runtime/deoptimization.hpp"
48 #include "runtime/interfaceSupport.hpp"
49 #include "runtime/sharedRuntime.hpp"
50 #include "runtime/signature.hpp"
51 #include "runtime/stubRoutines.hpp"
52 #include "runtime/thread.hpp"
53 #include "runtime/threadSMR.hpp"
54 #include "runtime/vframe.hpp"
55 #include "runtime/vframeArray.hpp"
56 #include "runtime/vframe_hp.hpp"
57 #include "utilities/events.hpp"
58 #include "utilities/xmlstream.hpp"
59
60 #if INCLUDE_JVMCI
61 #include "jvmci/jvmciRuntime.hpp"
62 #include "jvmci/jvmciJavaClasses.hpp"
63 #endif
64
65
66 bool DeoptimizationMarker::_is_active = false;
67
68 Deoptimization::UnrollBlock::UnrollBlock(int size_of_deoptimized_frame,
69 int caller_adjustment,
70 int caller_actual_parameters,
71 int number_of_frames,
72 intptr_t* frame_sizes,
73 address* frame_pcs,
74 BasicType return_type,
75 int exec_mode) {
76 _size_of_deoptimized_frame = size_of_deoptimized_frame;
77 _caller_adjustment = caller_adjustment;
78 _caller_actual_parameters = caller_actual_parameters;
79 _number_of_frames = number_of_frames;
80 _frame_sizes = frame_sizes;
81 _frame_pcs = frame_pcs;
82 _register_block = NEW_C_HEAP_ARRAY(intptr_t, RegisterMap::reg_count * 2, mtCompiler);
83 _return_type = return_type;
84 _initial_info = 0;
85 // PD (x86 only)
86 _counter_temp = 0;
87 _unpack_kind = exec_mode;
88 _sender_sp_temp = 0;
89
90 _total_frame_sizes = size_of_frames();
91 assert(exec_mode >= 0 && exec_mode < Unpack_LIMIT, "Unexpected exec_mode");
92 }
93
94
95 Deoptimization::UnrollBlock::~UnrollBlock() {
96 FREE_C_HEAP_ARRAY(intptr_t, _frame_sizes);
97 FREE_C_HEAP_ARRAY(intptr_t, _frame_pcs);
98 FREE_C_HEAP_ARRAY(intptr_t, _register_block);
99 }
100
101
102 intptr_t* Deoptimization::UnrollBlock::value_addr_at(int register_number) const {
103 assert(register_number < RegisterMap::reg_count, "checking register number");
104 return &_register_block[register_number * 2];
105 }
106
107
108
109 int Deoptimization::UnrollBlock::size_of_frames() const {
110 // Acount first for the adjustment of the initial frame
111 int result = _caller_adjustment;
112 for (int index = 0; index < number_of_frames(); index++) {
113 result += frame_sizes()[index];
114 }
115 return result;
116 }
117
118
119 void Deoptimization::UnrollBlock::print() {
120 ttyLocker ttyl;
121 tty->print_cr("UnrollBlock");
122 tty->print_cr(" size_of_deoptimized_frame = %d", _size_of_deoptimized_frame);
123 tty->print( " frame_sizes: ");
124 for (int index = 0; index < number_of_frames(); index++) {
125 tty->print(INTX_FORMAT " ", frame_sizes()[index]);
126 }
127 tty->cr();
128 }
129
130
131 // In order to make fetch_unroll_info work properly with escape
132 // analysis, The method was changed from JRT_LEAF to JRT_BLOCK_ENTRY and
133 // ResetNoHandleMark and HandleMark were removed from it. The actual reallocation
134 // of previously eliminated objects occurs in realloc_objects, which is
135 // called from the method fetch_unroll_info_helper below.
136 JRT_BLOCK_ENTRY(Deoptimization::UnrollBlock*, Deoptimization::fetch_unroll_info(JavaThread* thread, int exec_mode))
137 // It is actually ok to allocate handles in a leaf method. It causes no safepoints,
138 // but makes the entry a little slower. There is however a little dance we have to
139 // do in debug mode to get around the NoHandleMark code in the JRT_LEAF macro
140
141 // fetch_unroll_info() is called at the beginning of the deoptimization
142 // handler. Note this fact before we start generating temporary frames
143 // that can confuse an asynchronous stack walker. This counter is
144 // decremented at the end of unpack_frames().
145 if (TraceDeoptimization) {
146 tty->print_cr("Deoptimizing thread " INTPTR_FORMAT, p2i(thread));
147 }
148 thread->inc_in_deopt_handler();
149
150 return fetch_unroll_info_helper(thread, exec_mode);
151 JRT_END
152
153
154 // This is factored, since it is both called from a JRT_LEAF (deoptimization) and a JRT_ENTRY (uncommon_trap)
155 Deoptimization::UnrollBlock* Deoptimization::fetch_unroll_info_helper(JavaThread* thread, int exec_mode) {
156
157 // Note: there is a safepoint safety issue here. No matter whether we enter
158 // via vanilla deopt or uncommon trap we MUST NOT stop at a safepoint once
159 // the vframeArray is created.
160 //
161
162 // Allocate our special deoptimization ResourceMark
163 DeoptResourceMark* dmark = new DeoptResourceMark(thread);
164 assert(thread->deopt_mark() == NULL, "Pending deopt!");
165 thread->set_deopt_mark(dmark);
166
167 frame stub_frame = thread->last_frame(); // Makes stack walkable as side effect
168 RegisterMap map(thread, true);
169 RegisterMap dummy_map(thread, false);
170 // Now get the deoptee with a valid map
171 frame deoptee = stub_frame.sender(&map);
172 // Set the deoptee nmethod
173 assert(thread->deopt_compiled_method() == NULL, "Pending deopt!");
174 CompiledMethod* cm = deoptee.cb()->as_compiled_method_or_null();
175 thread->set_deopt_compiled_method(cm);
176
177 if (VerifyStack) {
178 thread->validate_frame_layout();
179 }
180
181 // Create a growable array of VFrames where each VFrame represents an inlined
182 // Java frame. This storage is allocated with the usual system arena.
183 assert(deoptee.is_compiled_frame(), "Wrong frame type");
184 GrowableArray<compiledVFrame*>* chunk = new GrowableArray<compiledVFrame*>(10);
185 vframe* vf = vframe::new_vframe(&deoptee, &map, thread);
186 while (!vf->is_top()) {
187 assert(vf->is_compiled_frame(), "Wrong frame type");
188 chunk->push(compiledVFrame::cast(vf));
189 vf = vf->sender();
190 }
191 assert(vf->is_compiled_frame(), "Wrong frame type");
192 chunk->push(compiledVFrame::cast(vf));
193
194 bool realloc_failures = false;
195
196 #if COMPILER2_OR_JVMCI
197 // Reallocate the non-escaping objects and restore their fields. Then
198 // relock objects if synchronization on them was eliminated.
199 #ifndef INCLUDE_JVMCI
200 if (DoEscapeAnalysis || EliminateNestedLocks) {
201 if (EliminateAllocations) {
202 #endif // INCLUDE_JVMCI
203 assert (chunk->at(0)->scope() != NULL,"expect only compiled java frames");
204 GrowableArray<ScopeValue*>* objects = chunk->at(0)->scope()->objects();
205
206 // The flag return_oop() indicates call sites which return oop
207 // in compiled code. Such sites include java method calls,
208 // runtime calls (for example, used to allocate new objects/arrays
209 // on slow code path) and any other calls generated in compiled code.
210 // It is not guaranteed that we can get such information here only
211 // by analyzing bytecode in deoptimized frames. This is why this flag
212 // is set during method compilation (see Compile::Process_OopMap_Node()).
213 // If the previous frame was popped or if we are dispatching an exception,
214 // we don't have an oop result.
215 bool save_oop_result = chunk->at(0)->scope()->return_oop() && !thread->popframe_forcing_deopt_reexecution() && (exec_mode == Unpack_deopt);
216 Handle return_value;
217 if (save_oop_result) {
218 // Reallocation may trigger GC. If deoptimization happened on return from
219 // call which returns oop we need to save it since it is not in oopmap.
220 oop result = deoptee.saved_oop_result(&map);
221 assert(oopDesc::is_oop_or_null(result), "must be oop");
222 return_value = Handle(thread, result);
223 assert(Universe::heap()->is_in_or_null(result), "must be heap pointer");
224 if (TraceDeoptimization) {
225 ttyLocker ttyl;
226 tty->print_cr("SAVED OOP RESULT " INTPTR_FORMAT " in thread " INTPTR_FORMAT, p2i(result), p2i(thread));
227 }
228 }
229 if (objects != NULL) {
230 JRT_BLOCK
231 realloc_failures = realloc_objects(thread, &deoptee, objects, THREAD);
232 JRT_END
233 bool skip_internal = (cm != NULL) && !cm->is_compiled_by_jvmci();
234 reassign_fields(&deoptee, &map, objects, realloc_failures, skip_internal);
235 #ifndef PRODUCT
236 if (TraceDeoptimization) {
237 ttyLocker ttyl;
238 tty->print_cr("REALLOC OBJECTS in thread " INTPTR_FORMAT, p2i(thread));
239 print_objects(objects, realloc_failures);
240 }
241 #endif
242 }
243 if (save_oop_result) {
244 // Restore result.
245 deoptee.set_saved_oop_result(&map, return_value());
246 }
247 #ifndef INCLUDE_JVMCI
248 }
249 if (EliminateLocks) {
250 #endif // INCLUDE_JVMCI
251 #ifndef PRODUCT
252 bool first = true;
253 #endif
254 for (int i = 0; i < chunk->length(); i++) {
255 compiledVFrame* cvf = chunk->at(i);
256 assert (cvf->scope() != NULL,"expect only compiled java frames");
257 GrowableArray<MonitorInfo*>* monitors = cvf->monitors();
258 if (monitors->is_nonempty()) {
259 relock_objects(monitors, thread, realloc_failures);
260 #ifndef PRODUCT
261 if (PrintDeoptimizationDetails) {
262 ttyLocker ttyl;
263 for (int j = 0; j < monitors->length(); j++) {
264 MonitorInfo* mi = monitors->at(j);
265 if (mi->eliminated()) {
266 if (first) {
267 first = false;
268 tty->print_cr("RELOCK OBJECTS in thread " INTPTR_FORMAT, p2i(thread));
269 }
270 if (mi->owner_is_scalar_replaced()) {
271 Klass* k = java_lang_Class::as_Klass(mi->owner_klass());
272 tty->print_cr(" failed reallocation for klass %s", k->external_name());
273 } else {
274 tty->print_cr(" object <" INTPTR_FORMAT "> locked", p2i(mi->owner()));
275 }
276 }
277 }
278 }
279 #endif // !PRODUCT
280 }
281 }
282 #ifndef INCLUDE_JVMCI
283 }
284 }
285 #endif // INCLUDE_JVMCI
286 #endif // COMPILER2_OR_JVMCI
287
288 ScopeDesc* trap_scope = chunk->at(0)->scope();
289 Handle exceptionObject;
290 if (trap_scope->rethrow_exception()) {
291 if (PrintDeoptimizationDetails) {
292 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());
293 }
294 GrowableArray<ScopeValue*>* expressions = trap_scope->expressions();
295 guarantee(expressions != NULL && expressions->length() > 0, "must have exception to throw");
296 ScopeValue* topOfStack = expressions->top();
297 exceptionObject = StackValue::create_stack_value(&deoptee, &map, topOfStack)->get_obj();
298 guarantee(exceptionObject() != NULL, "exception oop can not be null");
299 }
300
301 // Ensure that no safepoint is taken after pointers have been stored
302 // in fields of rematerialized objects. If a safepoint occurs from here on
303 // out the java state residing in the vframeArray will be missed.
304 NoSafepointVerifier no_safepoint;
305
306 vframeArray* array = create_vframeArray(thread, deoptee, &map, chunk, realloc_failures);
307 #if COMPILER2_OR_JVMCI
308 if (realloc_failures) {
309 pop_frames_failed_reallocs(thread, array);
310 }
311 #endif
312
313 assert(thread->vframe_array_head() == NULL, "Pending deopt!");
314 thread->set_vframe_array_head(array);
315
316 // Now that the vframeArray has been created if we have any deferred local writes
317 // added by jvmti then we can free up that structure as the data is now in the
318 // vframeArray
319
320 if (thread->deferred_locals() != NULL) {
321 GrowableArray<jvmtiDeferredLocalVariableSet*>* list = thread->deferred_locals();
322 int i = 0;
323 do {
324 // Because of inlining we could have multiple vframes for a single frame
325 // and several of the vframes could have deferred writes. Find them all.
326 if (list->at(i)->id() == array->original().id()) {
327 jvmtiDeferredLocalVariableSet* dlv = list->at(i);
328 list->remove_at(i);
329 // individual jvmtiDeferredLocalVariableSet are CHeapObj's
330 delete dlv;
331 } else {
332 i++;
333 }
334 } while ( i < list->length() );
335 if (list->length() == 0) {
336 thread->set_deferred_locals(NULL);
337 // free the list and elements back to C heap.
338 delete list;
339 }
340
341 }
342
343 // Compute the caller frame based on the sender sp of stub_frame and stored frame sizes info.
344 CodeBlob* cb = stub_frame.cb();
345 // Verify we have the right vframeArray
346 assert(cb->frame_size() >= 0, "Unexpected frame size");
347 intptr_t* unpack_sp = stub_frame.sp() + cb->frame_size();
348
349 // If the deopt call site is a MethodHandle invoke call site we have
350 // to adjust the unpack_sp.
351 nmethod* deoptee_nm = deoptee.cb()->as_nmethod_or_null();
352 if (deoptee_nm != NULL && deoptee_nm->is_method_handle_return(deoptee.pc()))
353 unpack_sp = deoptee.unextended_sp();
354
355 #ifdef ASSERT
356 assert(cb->is_deoptimization_stub() ||
357 cb->is_uncommon_trap_stub() ||
358 strcmp("Stub<DeoptimizationStub.deoptimizationHandler>", cb->name()) == 0 ||
359 strcmp("Stub<UncommonTrapStub.uncommonTrapHandler>", cb->name()) == 0,
360 "unexpected code blob: %s", cb->name());
361 #endif
362
363 // This is a guarantee instead of an assert because if vframe doesn't match
364 // we will unpack the wrong deoptimized frame and wind up in strange places
365 // where it will be very difficult to figure out what went wrong. Better
366 // to die an early death here than some very obscure death later when the
367 // trail is cold.
368 // Note: on ia64 this guarantee can be fooled by frames with no memory stack
369 // in that it will fail to detect a problem when there is one. This needs
370 // more work in tiger timeframe.
371 guarantee(array->unextended_sp() == unpack_sp, "vframe_array_head must contain the vframeArray to unpack");
372
373 int number_of_frames = array->frames();
374
375 // Compute the vframes' sizes. Note that frame_sizes[] entries are ordered from outermost to innermost
376 // virtual activation, which is the reverse of the elements in the vframes array.
377 intptr_t* frame_sizes = NEW_C_HEAP_ARRAY(intptr_t, number_of_frames, mtCompiler);
378 // +1 because we always have an interpreter return address for the final slot.
379 address* frame_pcs = NEW_C_HEAP_ARRAY(address, number_of_frames + 1, mtCompiler);
380 int popframe_extra_args = 0;
381 // Create an interpreter return address for the stub to use as its return
382 // address so the skeletal frames are perfectly walkable
383 frame_pcs[number_of_frames] = Interpreter::deopt_entry(vtos, 0);
384
385 // PopFrame requires that the preserved incoming arguments from the recently-popped topmost
386 // activation be put back on the expression stack of the caller for reexecution
387 if (JvmtiExport::can_pop_frame() && thread->popframe_forcing_deopt_reexecution()) {
388 popframe_extra_args = in_words(thread->popframe_preserved_args_size_in_words());
389 }
390
391 // Find the current pc for sender of the deoptee. Since the sender may have been deoptimized
392 // itself since the deoptee vframeArray was created we must get a fresh value of the pc rather
393 // than simply use array->sender.pc(). This requires us to walk the current set of frames
394 //
395 frame deopt_sender = stub_frame.sender(&dummy_map); // First is the deoptee frame
396 deopt_sender = deopt_sender.sender(&dummy_map); // Now deoptee caller
397
398 // It's possible that the number of parameters at the call site is
399 // different than number of arguments in the callee when method
400 // handles are used. If the caller is interpreted get the real
401 // value so that the proper amount of space can be added to it's
402 // frame.
403 bool caller_was_method_handle = false;
404 if (deopt_sender.is_interpreted_frame()) {
405 methodHandle method = deopt_sender.interpreter_frame_method();
406 Bytecode_invoke cur = Bytecode_invoke_check(method, deopt_sender.interpreter_frame_bci());
407 if (cur.is_invokedynamic() || cur.is_invokehandle()) {
408 // Method handle invokes may involve fairly arbitrary chains of
409 // calls so it's impossible to know how much actual space the
410 // caller has for locals.
411 caller_was_method_handle = true;
412 }
413 }
414
415 //
416 // frame_sizes/frame_pcs[0] oldest frame (int or c2i)
417 // frame_sizes/frame_pcs[1] next oldest frame (int)
418 // frame_sizes/frame_pcs[n] youngest frame (int)
419 //
420 // Now a pc in frame_pcs is actually the return address to the frame's caller (a frame
421 // owns the space for the return address to it's caller). Confusing ain't it.
422 //
423 // The vframe array can address vframes with indices running from
424 // 0.._frames-1. Index 0 is the youngest frame and _frame - 1 is the oldest (root) frame.
425 // When we create the skeletal frames we need the oldest frame to be in the zero slot
426 // in the frame_sizes/frame_pcs so the assembly code can do a trivial walk.
427 // so things look a little strange in this loop.
428 //
429 int callee_parameters = 0;
430 int callee_locals = 0;
431 for (int index = 0; index < array->frames(); index++ ) {
432 // frame[number_of_frames - 1 ] = on_stack_size(youngest)
433 // frame[number_of_frames - 2 ] = on_stack_size(sender(youngest))
434 // frame[number_of_frames - 3 ] = on_stack_size(sender(sender(youngest)))
435 frame_sizes[number_of_frames - 1 - index] = BytesPerWord * array->element(index)->on_stack_size(callee_parameters,
436 callee_locals,
437 index == 0,
438 popframe_extra_args);
439 // This pc doesn't have to be perfect just good enough to identify the frame
440 // as interpreted so the skeleton frame will be walkable
441 // The correct pc will be set when the skeleton frame is completely filled out
442 // The final pc we store in the loop is wrong and will be overwritten below
443 frame_pcs[number_of_frames - 1 - index ] = Interpreter::deopt_entry(vtos, 0) - frame::pc_return_offset;
444
445 callee_parameters = array->element(index)->method()->size_of_parameters();
446 callee_locals = array->element(index)->method()->max_locals();
447 popframe_extra_args = 0;
448 }
449
450 // Compute whether the root vframe returns a float or double value.
451 BasicType return_type;
452 {
453 methodHandle method(thread, array->element(0)->method());
454 Bytecode_invoke invoke = Bytecode_invoke_check(method, array->element(0)->bci());
455 return_type = invoke.is_valid() ? invoke.result_type() : T_ILLEGAL;
456 }
457
458 // Compute information for handling adapters and adjusting the frame size of the caller.
459 int caller_adjustment = 0;
460
461 // Compute the amount the oldest interpreter frame will have to adjust
462 // its caller's stack by. If the caller is a compiled frame then
463 // we pretend that the callee has no parameters so that the
464 // extension counts for the full amount of locals and not just
465 // locals-parms. This is because without a c2i adapter the parm
466 // area as created by the compiled frame will not be usable by
467 // the interpreter. (Depending on the calling convention there
468 // may not even be enough space).
469
470 // QQQ I'd rather see this pushed down into last_frame_adjust
471 // and have it take the sender (aka caller).
472
473 if (deopt_sender.is_compiled_frame() || caller_was_method_handle) {
474 caller_adjustment = last_frame_adjust(0, callee_locals);
475 } else if (callee_locals > callee_parameters) {
476 // The caller frame may need extending to accommodate
477 // non-parameter locals of the first unpacked interpreted frame.
478 // Compute that adjustment.
479 caller_adjustment = last_frame_adjust(callee_parameters, callee_locals);
480 }
481
482 // If the sender is deoptimized the we must retrieve the address of the handler
483 // since the frame will "magically" show the original pc before the deopt
484 // and we'd undo the deopt.
485
486 frame_pcs[0] = deopt_sender.raw_pc();
487
488 assert(CodeCache::find_blob_unsafe(frame_pcs[0]) != NULL, "bad pc");
489
490 #ifdef INCLUDE_JVMCI
491 if (exceptionObject() != NULL) {
492 thread->set_exception_oop(exceptionObject());
493 exec_mode = Unpack_exception;
494 }
495 #endif
496
497 if (thread->frames_to_pop_failed_realloc() > 0 && exec_mode != Unpack_uncommon_trap) {
498 assert(thread->has_pending_exception(), "should have thrown OOME");
499 thread->set_exception_oop(thread->pending_exception());
500 thread->clear_pending_exception();
501 exec_mode = Unpack_exception;
502 }
503
504 #if INCLUDE_JVMCI
505 if (thread->frames_to_pop_failed_realloc() > 0) {
506 thread->set_pending_monitorenter(false);
507 }
508 #endif
509
510 UnrollBlock* info = new UnrollBlock(array->frame_size() * BytesPerWord,
511 caller_adjustment * BytesPerWord,
512 caller_was_method_handle ? 0 : callee_parameters,
513 number_of_frames,
514 frame_sizes,
515 frame_pcs,
516 return_type,
517 exec_mode);
518 // On some platforms, we need a way to pass some platform dependent
519 // information to the unpacking code so the skeletal frames come out
520 // correct (initial fp value, unextended sp, ...)
521 info->set_initial_info((intptr_t) array->sender().initial_deoptimization_info());
522
523 if (array->frames() > 1) {
524 if (VerifyStack && TraceDeoptimization) {
525 ttyLocker ttyl;
526 tty->print_cr("Deoptimizing method containing inlining");
527 }
528 }
529
530 array->set_unroll_block(info);
531 return info;
532 }
533
534 // Called to cleanup deoptimization data structures in normal case
535 // after unpacking to stack and when stack overflow error occurs
536 void Deoptimization::cleanup_deopt_info(JavaThread *thread,
537 vframeArray *array) {
538
539 // Get array if coming from exception
540 if (array == NULL) {
541 array = thread->vframe_array_head();
542 }
543 thread->set_vframe_array_head(NULL);
544
545 // Free the previous UnrollBlock
546 vframeArray* old_array = thread->vframe_array_last();
547 thread->set_vframe_array_last(array);
548
549 if (old_array != NULL) {
550 UnrollBlock* old_info = old_array->unroll_block();
551 old_array->set_unroll_block(NULL);
552 delete old_info;
553 delete old_array;
554 }
555
556 // Deallocate any resource creating in this routine and any ResourceObjs allocated
557 // inside the vframeArray (StackValueCollections)
558
559 delete thread->deopt_mark();
560 thread->set_deopt_mark(NULL);
561 thread->set_deopt_compiled_method(NULL);
562
563
564 if (JvmtiExport::can_pop_frame()) {
565 #ifndef CC_INTERP
566 // Regardless of whether we entered this routine with the pending
567 // popframe condition bit set, we should always clear it now
568 thread->clear_popframe_condition();
569 #else
570 // C++ interpreter will clear has_pending_popframe when it enters
571 // with method_resume. For deopt_resume2 we clear it now.
572 if (thread->popframe_forcing_deopt_reexecution())
573 thread->clear_popframe_condition();
574 #endif /* CC_INTERP */
575 }
576
577 // unpack_frames() is called at the end of the deoptimization handler
578 // and (in C2) at the end of the uncommon trap handler. Note this fact
579 // so that an asynchronous stack walker can work again. This counter is
580 // incremented at the beginning of fetch_unroll_info() and (in C2) at
581 // the beginning of uncommon_trap().
582 thread->dec_in_deopt_handler();
583 }
584
585 // Moved from cpu directories because none of the cpus has callee save values.
586 // If a cpu implements callee save values, move this to deoptimization_<cpu>.cpp.
587 void Deoptimization::unwind_callee_save_values(frame* f, vframeArray* vframe_array) {
588
589 // This code is sort of the equivalent of C2IAdapter::setup_stack_frame back in
590 // the days we had adapter frames. When we deoptimize a situation where a
591 // compiled caller calls a compiled caller will have registers it expects
592 // to survive the call to the callee. If we deoptimize the callee the only
593 // way we can restore these registers is to have the oldest interpreter
594 // frame that we create restore these values. That is what this routine
595 // will accomplish.
596
597 // At the moment we have modified c2 to not have any callee save registers
598 // so this problem does not exist and this routine is just a place holder.
599
600 assert(f->is_interpreted_frame(), "must be interpreted");
601 }
602
603 // Return BasicType of value being returned
604 JRT_LEAF(BasicType, Deoptimization::unpack_frames(JavaThread* thread, int exec_mode))
605
606 // We are already active int he special DeoptResourceMark any ResourceObj's we
607 // allocate will be freed at the end of the routine.
608
609 // It is actually ok to allocate handles in a leaf method. It causes no safepoints,
610 // but makes the entry a little slower. There is however a little dance we have to
611 // do in debug mode to get around the NoHandleMark code in the JRT_LEAF macro
612 ResetNoHandleMark rnhm; // No-op in release/product versions
613 HandleMark hm;
614
615 frame stub_frame = thread->last_frame();
616
617 // Since the frame to unpack is the top frame of this thread, the vframe_array_head
618 // must point to the vframeArray for the unpack frame.
619 vframeArray* array = thread->vframe_array_head();
620
621 #ifndef PRODUCT
622 if (TraceDeoptimization) {
623 ttyLocker ttyl;
624 tty->print_cr("DEOPT UNPACKING thread " INTPTR_FORMAT " vframeArray " INTPTR_FORMAT " mode %d",
625 p2i(thread), p2i(array), exec_mode);
626 }
627 #endif
628 Events::log(thread, "DEOPT UNPACKING pc=" INTPTR_FORMAT " sp=" INTPTR_FORMAT " mode %d",
629 p2i(stub_frame.pc()), p2i(stub_frame.sp()), exec_mode);
630
631 UnrollBlock* info = array->unroll_block();
632
633 // Unpack the interpreter frames and any adapter frame (c2 only) we might create.
634 array->unpack_to_stack(stub_frame, exec_mode, info->caller_actual_parameters());
635
636 BasicType bt = info->return_type();
637
638 // If we have an exception pending, claim that the return type is an oop
639 // so the deopt_blob does not overwrite the exception_oop.
640
641 if (exec_mode == Unpack_exception)
642 bt = T_OBJECT;
643
644 // Cleanup thread deopt data
645 cleanup_deopt_info(thread, array);
646
647 #ifndef PRODUCT
648 if (VerifyStack) {
649 ResourceMark res_mark;
650
651 thread->validate_frame_layout();
652
653 // Verify that the just-unpacked frames match the interpreter's
654 // notions of expression stack and locals
655 vframeArray* cur_array = thread->vframe_array_last();
656 RegisterMap rm(thread, false);
657 rm.set_include_argument_oops(false);
658 bool is_top_frame = true;
659 int callee_size_of_parameters = 0;
660 int callee_max_locals = 0;
661 for (int i = 0; i < cur_array->frames(); i++) {
662 vframeArrayElement* el = cur_array->element(i);
663 frame* iframe = el->iframe();
664 guarantee(iframe->is_interpreted_frame(), "Wrong frame type");
665
666 // Get the oop map for this bci
667 InterpreterOopMap mask;
668 int cur_invoke_parameter_size = 0;
669 bool try_next_mask = false;
670 int next_mask_expression_stack_size = -1;
671 int top_frame_expression_stack_adjustment = 0;
672 methodHandle mh(thread, iframe->interpreter_frame_method());
673 OopMapCache::compute_one_oop_map(mh, iframe->interpreter_frame_bci(), &mask);
674 BytecodeStream str(mh);
675 str.set_start(iframe->interpreter_frame_bci());
676 int max_bci = mh->code_size();
677 // Get to the next bytecode if possible
678 assert(str.bci() < max_bci, "bci in interpreter frame out of bounds");
679 // Check to see if we can grab the number of outgoing arguments
680 // at an uncommon trap for an invoke (where the compiler
681 // generates debug info before the invoke has executed)
682 Bytecodes::Code cur_code = str.next();
683 if (cur_code == Bytecodes::_invokevirtual ||
684 cur_code == Bytecodes::_invokespecial ||
685 cur_code == Bytecodes::_invokestatic ||
686 cur_code == Bytecodes::_invokeinterface ||
687 cur_code == Bytecodes::_invokedynamic) {
688 Bytecode_invoke invoke(mh, iframe->interpreter_frame_bci());
689 Symbol* signature = invoke.signature();
690 ArgumentSizeComputer asc(signature);
691 cur_invoke_parameter_size = asc.size();
692 if (invoke.has_receiver()) {
693 // Add in receiver
694 ++cur_invoke_parameter_size;
695 }
696 if (i != 0 && !invoke.is_invokedynamic() && MethodHandles::has_member_arg(invoke.klass(), invoke.name())) {
697 callee_size_of_parameters++;
698 }
699 }
700 if (str.bci() < max_bci) {
701 Bytecodes::Code bc = str.next();
702 if (bc >= 0) {
703 // The interpreter oop map generator reports results before
704 // the current bytecode has executed except in the case of
705 // calls. It seems to be hard to tell whether the compiler
706 // has emitted debug information matching the "state before"
707 // a given bytecode or the state after, so we try both
708 switch (cur_code) {
709 case Bytecodes::_invokevirtual:
710 case Bytecodes::_invokespecial:
711 case Bytecodes::_invokestatic:
712 case Bytecodes::_invokeinterface:
713 case Bytecodes::_invokedynamic:
714 case Bytecodes::_athrow:
715 break;
716 default: {
717 InterpreterOopMap next_mask;
718 OopMapCache::compute_one_oop_map(mh, str.bci(), &next_mask);
719 next_mask_expression_stack_size = next_mask.expression_stack_size();
720 // Need to subtract off the size of the result type of
721 // the bytecode because this is not described in the
722 // debug info but returned to the interpreter in the TOS
723 // caching register
724 BasicType bytecode_result_type = Bytecodes::result_type(cur_code);
725 if (bytecode_result_type != T_ILLEGAL) {
726 top_frame_expression_stack_adjustment = type2size[bytecode_result_type];
727 }
728 assert(top_frame_expression_stack_adjustment >= 0, "");
729 try_next_mask = true;
730 break;
731 }
732 }
733 }
734 }
735
736 // Verify stack depth and oops in frame
737 // This assertion may be dependent on the platform we're running on and may need modification (tested on x86 and sparc)
738 if (!(
739 /* SPARC */
740 (iframe->interpreter_frame_expression_stack_size() == mask.expression_stack_size() + callee_size_of_parameters) ||
741 /* x86 */
742 (iframe->interpreter_frame_expression_stack_size() == mask.expression_stack_size() + callee_max_locals) ||
743 (try_next_mask &&
744 (iframe->interpreter_frame_expression_stack_size() == (next_mask_expression_stack_size -
745 top_frame_expression_stack_adjustment))) ||
746 (is_top_frame && (exec_mode == Unpack_exception) && iframe->interpreter_frame_expression_stack_size() == 0) ||
747 (is_top_frame && (exec_mode == Unpack_uncommon_trap || exec_mode == Unpack_reexecute || el->should_reexecute()) &&
748 (iframe->interpreter_frame_expression_stack_size() == mask.expression_stack_size() + cur_invoke_parameter_size))
749 )) {
750 ttyLocker ttyl;
751
752 // Print out some information that will help us debug the problem
753 tty->print_cr("Wrong number of expression stack elements during deoptimization");
754 tty->print_cr(" Error occurred while verifying frame %d (0..%d, 0 is topmost)", i, cur_array->frames() - 1);
755 tty->print_cr(" Fabricated interpreter frame had %d expression stack elements",
756 iframe->interpreter_frame_expression_stack_size());
757 tty->print_cr(" Interpreter oop map had %d expression stack elements", mask.expression_stack_size());
758 tty->print_cr(" try_next_mask = %d", try_next_mask);
759 tty->print_cr(" next_mask_expression_stack_size = %d", next_mask_expression_stack_size);
760 tty->print_cr(" callee_size_of_parameters = %d", callee_size_of_parameters);
761 tty->print_cr(" callee_max_locals = %d", callee_max_locals);
762 tty->print_cr(" top_frame_expression_stack_adjustment = %d", top_frame_expression_stack_adjustment);
763 tty->print_cr(" exec_mode = %d", exec_mode);
764 tty->print_cr(" cur_invoke_parameter_size = %d", cur_invoke_parameter_size);
765 tty->print_cr(" Thread = " INTPTR_FORMAT ", thread ID = %d", p2i(thread), thread->osthread()->thread_id());
766 tty->print_cr(" Interpreted frames:");
767 for (int k = 0; k < cur_array->frames(); k++) {
768 vframeArrayElement* el = cur_array->element(k);
769 tty->print_cr(" %s (bci %d)", el->method()->name_and_sig_as_C_string(), el->bci());
770 }
771 cur_array->print_on_2(tty);
772 guarantee(false, "wrong number of expression stack elements during deopt");
773 }
774 VerifyOopClosure verify;
775 iframe->oops_interpreted_do(&verify, &rm, false);
776 callee_size_of_parameters = mh->size_of_parameters();
777 callee_max_locals = mh->max_locals();
778 is_top_frame = false;
779 }
780 }
781 #endif /* !PRODUCT */
782
783
784 return bt;
785 JRT_END
786
787
788 int Deoptimization::deoptimize_dependents() {
789 Threads::deoptimized_wrt_marked_nmethods();
790 return 0;
791 }
792
793 Deoptimization::DeoptAction Deoptimization::_unloaded_action
794 = Deoptimization::Action_reinterpret;
795
796 #if COMPILER2_OR_JVMCI
797 bool Deoptimization::realloc_objects(JavaThread* thread, frame* fr, GrowableArray<ScopeValue*>* objects, TRAPS) {
798 Handle pending_exception(THREAD, thread->pending_exception());
799 const char* exception_file = thread->exception_file();
800 int exception_line = thread->exception_line();
801 thread->clear_pending_exception();
802
803 bool failures = false;
804
805 for (int i = 0; i < objects->length(); i++) {
806 assert(objects->at(i)->is_object(), "invalid debug information");
807 ObjectValue* sv = (ObjectValue*) objects->at(i);
808
809 Klass* k = java_lang_Class::as_Klass(sv->klass()->as_ConstantOopReadValue()->value()());
810 oop obj = NULL;
811
812 if (k->is_instance_klass()) {
813 InstanceKlass* ik = InstanceKlass::cast(k);
814 obj = ik->allocate_instance(THREAD);
815 } else if (k->is_typeArray_klass()) {
816 TypeArrayKlass* ak = TypeArrayKlass::cast(k);
817 assert(sv->field_size() % type2size[ak->element_type()] == 0, "non-integral array length");
818 int len = sv->field_size() / type2size[ak->element_type()];
819 obj = ak->allocate(len, THREAD);
820 } else if (k->is_objArray_klass()) {
821 ObjArrayKlass* ak = ObjArrayKlass::cast(k);
822 obj = ak->allocate(sv->field_size(), THREAD);
823 }
824
825 if (obj == NULL) {
826 failures = true;
827 }
828
829 assert(sv->value().is_null(), "redundant reallocation");
830 assert(obj != NULL || HAS_PENDING_EXCEPTION, "allocation should succeed or we should get an exception");
831 CLEAR_PENDING_EXCEPTION;
832 sv->set_value(obj);
833 }
834
835 if (failures) {
836 THROW_OOP_(Universe::out_of_memory_error_realloc_objects(), failures);
837 } else if (pending_exception.not_null()) {
838 thread->set_pending_exception(pending_exception(), exception_file, exception_line);
839 }
840
841 return failures;
842 }
843
844 // restore elements of an eliminated type array
845 void Deoptimization::reassign_type_array_elements(frame* fr, RegisterMap* reg_map, ObjectValue* sv, typeArrayOop obj, BasicType type) {
846 int index = 0;
847 intptr_t val;
848
849 for (int i = 0; i < sv->field_size(); i++) {
850 StackValue* value = StackValue::create_stack_value(fr, reg_map, sv->field_at(i));
851 switch(type) {
852 case T_LONG: case T_DOUBLE: {
853 assert(value->type() == T_INT, "Agreement.");
854 StackValue* low =
855 StackValue::create_stack_value(fr, reg_map, sv->field_at(++i));
856 #ifdef _LP64
857 jlong res = (jlong)low->get_int();
858 #else
859 #ifdef SPARC
860 // For SPARC we have to swap high and low words.
861 jlong res = jlong_from((jint)low->get_int(), (jint)value->get_int());
862 #else
863 jlong res = jlong_from((jint)value->get_int(), (jint)low->get_int());
864 #endif //SPARC
865 #endif
866 obj->long_at_put(index, res);
867 break;
868 }
869
870 // Have to cast to INT (32 bits) pointer to avoid little/big-endian problem.
871 case T_INT: case T_FLOAT: { // 4 bytes.
872 assert(value->type() == T_INT, "Agreement.");
873 bool big_value = false;
874 if (i + 1 < sv->field_size() && type == T_INT) {
875 if (sv->field_at(i)->is_location()) {
876 Location::Type type = ((LocationValue*) sv->field_at(i))->location().type();
877 if (type == Location::dbl || type == Location::lng) {
878 big_value = true;
879 }
880 } else if (sv->field_at(i)->is_constant_int()) {
881 ScopeValue* next_scope_field = sv->field_at(i + 1);
882 if (next_scope_field->is_constant_long() || next_scope_field->is_constant_double()) {
883 big_value = true;
884 }
885 }
886 }
887
888 if (big_value) {
889 StackValue* low = StackValue::create_stack_value(fr, reg_map, sv->field_at(++i));
890 #ifdef _LP64
891 jlong res = (jlong)low->get_int();
892 #else
893 #ifdef SPARC
894 // For SPARC we have to swap high and low words.
895 jlong res = jlong_from((jint)low->get_int(), (jint)value->get_int());
896 #else
897 jlong res = jlong_from((jint)value->get_int(), (jint)low->get_int());
898 #endif //SPARC
899 #endif
900 obj->int_at_put(index, (jint)*((jint*)&res));
901 obj->int_at_put(++index, (jint)*(((jint*)&res) + 1));
902 } else {
903 val = value->get_int();
904 obj->int_at_put(index, (jint)*((jint*)&val));
905 }
906 break;
907 }
908
909 case T_SHORT:
910 assert(value->type() == T_INT, "Agreement.");
911 val = value->get_int();
912 obj->short_at_put(index, (jshort)*((jint*)&val));
913 break;
914
915 case T_CHAR:
916 assert(value->type() == T_INT, "Agreement.");
917 val = value->get_int();
918 obj->char_at_put(index, (jchar)*((jint*)&val));
919 break;
920
921 case T_BYTE:
922 assert(value->type() == T_INT, "Agreement.");
923 val = value->get_int();
924 obj->byte_at_put(index, (jbyte)*((jint*)&val));
925 break;
926
927 case T_BOOLEAN:
928 assert(value->type() == T_INT, "Agreement.");
929 val = value->get_int();
930 obj->bool_at_put(index, (jboolean)*((jint*)&val));
931 break;
932
933 default:
934 ShouldNotReachHere();
935 }
936 index++;
937 }
938 }
939
940
941 // restore fields of an eliminated object array
942 void Deoptimization::reassign_object_array_elements(frame* fr, RegisterMap* reg_map, ObjectValue* sv, objArrayOop obj) {
943 for (int i = 0; i < sv->field_size(); i++) {
944 StackValue* value = StackValue::create_stack_value(fr, reg_map, sv->field_at(i));
945 assert(value->type() == T_OBJECT, "object element expected");
946 obj->obj_at_put(i, value->get_obj()());
947 }
948 }
949
950 class ReassignedField {
951 public:
952 int _offset;
953 BasicType _type;
954 public:
955 ReassignedField() {
956 _offset = 0;
957 _type = T_ILLEGAL;
958 }
959 };
960
961 int compare(ReassignedField* left, ReassignedField* right) {
962 return left->_offset - right->_offset;
963 }
964
965 // Restore fields of an eliminated instance object using the same field order
966 // returned by HotSpotResolvedObjectTypeImpl.getInstanceFields(true)
967 static int reassign_fields_by_klass(InstanceKlass* klass, frame* fr, RegisterMap* reg_map, ObjectValue* sv, int svIndex, oop obj, bool skip_internal) {
968 if (klass->superklass() != NULL) {
969 svIndex = reassign_fields_by_klass(klass->superklass(), fr, reg_map, sv, svIndex, obj, skip_internal);
970 }
971
972 GrowableArray<ReassignedField>* fields = new GrowableArray<ReassignedField>();
973 for (AllFieldStream fs(klass); !fs.done(); fs.next()) {
974 if (!fs.access_flags().is_static() && (!skip_internal || !fs.access_flags().is_internal())) {
975 ReassignedField field;
976 field._offset = fs.offset();
977 field._type = FieldType::basic_type(fs.signature());
978 fields->append(field);
979 }
980 }
981 fields->sort(compare);
982 for (int i = 0; i < fields->length(); i++) {
983 intptr_t val;
984 ScopeValue* scope_field = sv->field_at(svIndex);
985 StackValue* value = StackValue::create_stack_value(fr, reg_map, scope_field);
986 int offset = fields->at(i)._offset;
987 BasicType type = fields->at(i)._type;
988 switch (type) {
989 case T_OBJECT: case T_ARRAY:
990 assert(value->type() == T_OBJECT, "Agreement.");
991 obj->obj_field_put(offset, value->get_obj()());
992 break;
993
994 // Have to cast to INT (32 bits) pointer to avoid little/big-endian problem.
995 case T_INT: case T_FLOAT: { // 4 bytes.
996 assert(value->type() == T_INT, "Agreement.");
997 bool big_value = false;
998 if (i+1 < fields->length() && fields->at(i+1)._type == T_INT) {
999 if (scope_field->is_location()) {
1000 Location::Type type = ((LocationValue*) scope_field)->location().type();
1001 if (type == Location::dbl || type == Location::lng) {
1002 big_value = true;
1003 }
1004 }
1005 if (scope_field->is_constant_int()) {
1006 ScopeValue* next_scope_field = sv->field_at(svIndex + 1);
1007 if (next_scope_field->is_constant_long() || next_scope_field->is_constant_double()) {
1008 big_value = true;
1009 }
1010 }
1011 }
1012
1013 if (big_value) {
1014 i++;
1015 assert(i < fields->length(), "second T_INT field needed");
1016 assert(fields->at(i)._type == T_INT, "T_INT field needed");
1017 } else {
1018 val = value->get_int();
1019 obj->int_field_put(offset, (jint)*((jint*)&val));
1020 break;
1021 }
1022 }
1023 /* no break */
1024
1025 case T_LONG: case T_DOUBLE: {
1026 assert(value->type() == T_INT, "Agreement.");
1027 StackValue* low = StackValue::create_stack_value(fr, reg_map, sv->field_at(++svIndex));
1028 #ifdef _LP64
1029 jlong res = (jlong)low->get_int();
1030 #else
1031 #ifdef SPARC
1032 // For SPARC we have to swap high and low words.
1033 jlong res = jlong_from((jint)low->get_int(), (jint)value->get_int());
1034 #else
1035 jlong res = jlong_from((jint)value->get_int(), (jint)low->get_int());
1036 #endif //SPARC
1037 #endif
1038 obj->long_field_put(offset, res);
1039 break;
1040 }
1041
1042 case T_SHORT:
1043 assert(value->type() == T_INT, "Agreement.");
1044 val = value->get_int();
1045 obj->short_field_put(offset, (jshort)*((jint*)&val));
1046 break;
1047
1048 case T_CHAR:
1049 assert(value->type() == T_INT, "Agreement.");
1050 val = value->get_int();
1051 obj->char_field_put(offset, (jchar)*((jint*)&val));
1052 break;
1053
1054 case T_BYTE:
1055 assert(value->type() == T_INT, "Agreement.");
1056 val = value->get_int();
1057 obj->byte_field_put(offset, (jbyte)*((jint*)&val));
1058 break;
1059
1060 case T_BOOLEAN:
1061 assert(value->type() == T_INT, "Agreement.");
1062 val = value->get_int();
1063 obj->bool_field_put(offset, (jboolean)*((jint*)&val));
1064 break;
1065
1066 default:
1067 ShouldNotReachHere();
1068 }
1069 svIndex++;
1070 }
1071 return svIndex;
1072 }
1073
1074 // restore fields of all eliminated objects and arrays
1075 void Deoptimization::reassign_fields(frame* fr, RegisterMap* reg_map, GrowableArray<ScopeValue*>* objects, bool realloc_failures, bool skip_internal) {
1076 for (int i = 0; i < objects->length(); i++) {
1077 ObjectValue* sv = (ObjectValue*) objects->at(i);
1078 Klass* k = java_lang_Class::as_Klass(sv->klass()->as_ConstantOopReadValue()->value()());
1079 Handle obj = sv->value();
1080 assert(obj.not_null() || realloc_failures, "reallocation was missed");
1081 if (PrintDeoptimizationDetails) {
1082 tty->print_cr("reassign fields for object of type %s!", k->name()->as_C_string());
1083 }
1084 if (obj.is_null()) {
1085 continue;
1086 }
1087
1088 if (k->is_instance_klass()) {
1089 InstanceKlass* ik = InstanceKlass::cast(k);
1090 reassign_fields_by_klass(ik, fr, reg_map, sv, 0, obj(), skip_internal);
1091 } else if (k->is_typeArray_klass()) {
1092 TypeArrayKlass* ak = TypeArrayKlass::cast(k);
1093 reassign_type_array_elements(fr, reg_map, sv, (typeArrayOop) obj(), ak->element_type());
1094 } else if (k->is_objArray_klass()) {
1095 reassign_object_array_elements(fr, reg_map, sv, (objArrayOop) obj());
1096 }
1097 }
1098 }
1099
1100
1101 // relock objects for which synchronization was eliminated
1102 void Deoptimization::relock_objects(GrowableArray<MonitorInfo*>* monitors, JavaThread* thread, bool realloc_failures) {
1103 for (int i = 0; i < monitors->length(); i++) {
1104 MonitorInfo* mon_info = monitors->at(i);
1105 if (mon_info->eliminated()) {
1106 assert(!mon_info->owner_is_scalar_replaced() || realloc_failures, "reallocation was missed");
1107 if (!mon_info->owner_is_scalar_replaced()) {
1108 Handle obj(thread, mon_info->owner());
1109 markOop mark = obj->mark();
1110 if (UseBiasedLocking && mark->has_bias_pattern()) {
1111 // New allocated objects may have the mark set to anonymously biased.
1112 // Also the deoptimized method may called methods with synchronization
1113 // where the thread-local object is bias locked to the current thread.
1114 assert(mark->is_biased_anonymously() ||
1115 mark->biased_locker() == thread, "should be locked to current thread");
1116 // Reset mark word to unbiased prototype.
1117 markOop unbiased_prototype = markOopDesc::prototype()->set_age(mark->age());
1118 obj->set_mark(unbiased_prototype);
1119 }
1120 BasicLock* lock = mon_info->lock();
1121 ObjectSynchronizer::slow_enter(obj, lock, thread);
1122 assert(mon_info->owner()->is_locked(), "object must be locked now");
1123 }
1124 }
1125 }
1126 }
1127
1128
1129 #ifndef PRODUCT
1130 // print information about reallocated objects
1131 void Deoptimization::print_objects(GrowableArray<ScopeValue*>* objects, bool realloc_failures) {
1132 fieldDescriptor fd;
1133
1134 for (int i = 0; i < objects->length(); i++) {
1135 ObjectValue* sv = (ObjectValue*) objects->at(i);
1136 Klass* k = java_lang_Class::as_Klass(sv->klass()->as_ConstantOopReadValue()->value()());
1137 Handle obj = sv->value();
1138
1139 tty->print(" object <" INTPTR_FORMAT "> of type ", p2i(sv->value()()));
1140 k->print_value();
1141 assert(obj.not_null() || realloc_failures, "reallocation was missed");
1142 if (obj.is_null()) {
1143 tty->print(" allocation failed");
1144 } else {
1145 tty->print(" allocated (%d bytes)", obj->size() * HeapWordSize);
1146 }
1147 tty->cr();
1148
1149 if (Verbose && !obj.is_null()) {
1150 k->oop_print_on(obj(), tty);
1151 }
1152 }
1153 }
1154 #endif
1155 #endif // COMPILER2_OR_JVMCI
1156
1157 vframeArray* Deoptimization::create_vframeArray(JavaThread* thread, frame fr, RegisterMap *reg_map, GrowableArray<compiledVFrame*>* chunk, bool realloc_failures) {
1158 Events::log(thread, "DEOPT PACKING pc=" INTPTR_FORMAT " sp=" INTPTR_FORMAT, p2i(fr.pc()), p2i(fr.sp()));
1159
1160 #ifndef PRODUCT
1161 if (PrintDeoptimizationDetails) {
1162 ttyLocker ttyl;
1163 tty->print("DEOPT PACKING thread " INTPTR_FORMAT " ", p2i(thread));
1164 fr.print_on(tty);
1165 tty->print_cr(" Virtual frames (innermost first):");
1166 for (int index = 0; index < chunk->length(); index++) {
1167 compiledVFrame* vf = chunk->at(index);
1168 tty->print(" %2d - ", index);
1169 vf->print_value();
1170 int bci = chunk->at(index)->raw_bci();
1171 const char* code_name;
1172 if (bci == SynchronizationEntryBCI) {
1173 code_name = "sync entry";
1174 } else {
1175 Bytecodes::Code code = vf->method()->code_at(bci);
1176 code_name = Bytecodes::name(code);
1177 }
1178 tty->print(" - %s", code_name);
1179 tty->print_cr(" @ bci %d ", bci);
1180 if (Verbose) {
1181 vf->print();
1182 tty->cr();
1183 }
1184 }
1185 }
1186 #endif
1187
1188 // Register map for next frame (used for stack crawl). We capture
1189 // the state of the deopt'ing frame's caller. Thus if we need to
1190 // stuff a C2I adapter we can properly fill in the callee-save
1191 // register locations.
1192 frame caller = fr.sender(reg_map);
1193 int frame_size = caller.sp() - fr.sp();
1194
1195 frame sender = caller;
1196
1197 // Since the Java thread being deoptimized will eventually adjust it's own stack,
1198 // the vframeArray containing the unpacking information is allocated in the C heap.
1199 // For Compiler1, the caller of the deoptimized frame is saved for use by unpack_frames().
1200 vframeArray* array = vframeArray::allocate(thread, frame_size, chunk, reg_map, sender, caller, fr, realloc_failures);
1201
1202 // Compare the vframeArray to the collected vframes
1203 assert(array->structural_compare(thread, chunk), "just checking");
1204
1205 #ifndef PRODUCT
1206 if (PrintDeoptimizationDetails) {
1207 ttyLocker ttyl;
1208 tty->print_cr(" Created vframeArray " INTPTR_FORMAT, p2i(array));
1209 }
1210 #endif // PRODUCT
1211
1212 return array;
1213 }
1214
1215 #if COMPILER2_OR_JVMCI
1216 void Deoptimization::pop_frames_failed_reallocs(JavaThread* thread, vframeArray* array) {
1217 // Reallocation of some scalar replaced objects failed. Record
1218 // that we need to pop all the interpreter frames for the
1219 // deoptimized compiled frame.
1220 assert(thread->frames_to_pop_failed_realloc() == 0, "missed frames to pop?");
1221 thread->set_frames_to_pop_failed_realloc(array->frames());
1222 // Unlock all monitors here otherwise the interpreter will see a
1223 // mix of locked and unlocked monitors (because of failed
1224 // reallocations of synchronized objects) and be confused.
1225 for (int i = 0; i < array->frames(); i++) {
1226 MonitorChunk* monitors = array->element(i)->monitors();
1227 if (monitors != NULL) {
1228 for (int j = 0; j < monitors->number_of_monitors(); j++) {
1229 BasicObjectLock* src = monitors->at(j);
1230 if (src->obj() != NULL) {
1231 ObjectSynchronizer::fast_exit(src->obj(), src->lock(), thread);
1232 }
1233 }
1234 array->element(i)->free_monitors(thread);
1235 #ifdef ASSERT
1236 array->element(i)->set_removed_monitors();
1237 #endif
1238 }
1239 }
1240 }
1241 #endif
1242
1243 static void collect_monitors(compiledVFrame* cvf, GrowableArray<Handle>* objects_to_revoke) {
1244 GrowableArray<MonitorInfo*>* monitors = cvf->monitors();
1245 Thread* thread = Thread::current();
1246 for (int i = 0; i < monitors->length(); i++) {
1247 MonitorInfo* mon_info = monitors->at(i);
1248 if (!mon_info->eliminated() && mon_info->owner() != NULL) {
1249 objects_to_revoke->append(Handle(thread, mon_info->owner()));
1250 }
1251 }
1252 }
1253
1254
1255 void Deoptimization::revoke_biases_of_monitors(JavaThread* thread, frame fr, RegisterMap* map) {
1256 if (!UseBiasedLocking) {
1257 return;
1258 }
1259
1260 GrowableArray<Handle>* objects_to_revoke = new GrowableArray<Handle>();
1261
1262 // Unfortunately we don't have a RegisterMap available in most of
1263 // the places we want to call this routine so we need to walk the
1264 // stack again to update the register map.
1265 if (map == NULL || !map->update_map()) {
1266 StackFrameStream sfs(thread, true);
1267 bool found = false;
1268 while (!found && !sfs.is_done()) {
1269 frame* cur = sfs.current();
1270 sfs.next();
1271 found = cur->id() == fr.id();
1272 }
1273 assert(found, "frame to be deoptimized not found on target thread's stack");
1274 map = sfs.register_map();
1275 }
1276
1277 vframe* vf = vframe::new_vframe(&fr, map, thread);
1278 compiledVFrame* cvf = compiledVFrame::cast(vf);
1279 // Revoke monitors' biases in all scopes
1280 while (!cvf->is_top()) {
1281 collect_monitors(cvf, objects_to_revoke);
1282 cvf = compiledVFrame::cast(cvf->sender());
1283 }
1284 collect_monitors(cvf, objects_to_revoke);
1285
1286 if (SafepointSynchronize::is_at_safepoint()) {
1287 BiasedLocking::revoke_at_safepoint(objects_to_revoke);
1288 } else {
1289 BiasedLocking::revoke(objects_to_revoke);
1290 }
1291 }
1292
1293
1294 void Deoptimization::revoke_biases_of_monitors(CodeBlob* cb) {
1295 if (!UseBiasedLocking) {
1296 return;
1297 }
1298
1299 assert(SafepointSynchronize::is_at_safepoint(), "must only be called from safepoint");
1300 GrowableArray<Handle>* objects_to_revoke = new GrowableArray<Handle>();
1301 for (JavaThreadIteratorWithHandle jtiwh; JavaThread *jt = jtiwh.next(); ) {
1302 if (jt->has_last_Java_frame()) {
1303 StackFrameStream sfs(jt, true);
1304 while (!sfs.is_done()) {
1305 frame* cur = sfs.current();
1306 if (cb->contains(cur->pc())) {
1307 vframe* vf = vframe::new_vframe(cur, sfs.register_map(), jt);
1308 compiledVFrame* cvf = compiledVFrame::cast(vf);
1309 // Revoke monitors' biases in all scopes
1310 while (!cvf->is_top()) {
1311 collect_monitors(cvf, objects_to_revoke);
1312 cvf = compiledVFrame::cast(cvf->sender());
1313 }
1314 collect_monitors(cvf, objects_to_revoke);
1315 }
1316 sfs.next();
1317 }
1318 }
1319 }
1320 BiasedLocking::revoke_at_safepoint(objects_to_revoke);
1321 }
1322
1323
1324 void Deoptimization::deoptimize_single_frame(JavaThread* thread, frame fr, Deoptimization::DeoptReason reason) {
1325 assert(fr.can_be_deoptimized(), "checking frame type");
1326
1327 gather_statistics(reason, Action_none, Bytecodes::_illegal);
1328
1329 if (LogCompilation && xtty != NULL) {
1330 CompiledMethod* cm = fr.cb()->as_compiled_method_or_null();
1331 assert(cm != NULL, "only compiled methods can deopt");
1332
1333 ttyLocker ttyl;
1334 xtty->begin_head("deoptimized thread='" UINTX_FORMAT "' reason='%s' pc='" INTPTR_FORMAT "'",(uintx)thread->osthread()->thread_id(), trap_reason_name(reason), p2i(fr.pc()));
1335 cm->log_identity(xtty);
1336 xtty->end_head();
1337 for (ScopeDesc* sd = cm->scope_desc_at(fr.pc()); ; sd = sd->sender()) {
1338 xtty->begin_elem("jvms bci='%d'", sd->bci());
1339 xtty->method(sd->method());
1340 xtty->end_elem();
1341 if (sd->is_top()) break;
1342 }
1343 xtty->tail("deoptimized");
1344 }
1345
1346 // Patch the compiled method so that when execution returns to it we will
1347 // deopt the execution state and return to the interpreter.
1348 fr.deoptimize(thread);
1349 }
1350
1351 void Deoptimization::deoptimize(JavaThread* thread, frame fr, RegisterMap *map) {
1352 deoptimize(thread, fr, map, Reason_constraint);
1353 }
1354
1355 void Deoptimization::deoptimize(JavaThread* thread, frame fr, RegisterMap *map, DeoptReason reason) {
1356 // Deoptimize only if the frame comes from compile code.
1357 // Do not deoptimize the frame which is already patched
1358 // during the execution of the loops below.
1359 if (!fr.is_compiled_frame() || fr.is_deoptimized_frame()) {
1360 return;
1361 }
1362 ResourceMark rm;
1363 DeoptimizationMarker dm;
1364 if (UseBiasedLocking) {
1365 revoke_biases_of_monitors(thread, fr, map);
1366 }
1367 deoptimize_single_frame(thread, fr, reason);
1368
1369 }
1370
1371 #if INCLUDE_JVMCI
1372 address Deoptimization::deoptimize_for_missing_exception_handler(CompiledMethod* cm) {
1373 // there is no exception handler for this pc => deoptimize
1374 cm->make_not_entrant();
1375
1376 // Use Deoptimization::deoptimize for all of its side-effects:
1377 // revoking biases of monitors, gathering traps statistics, logging...
1378 // it also patches the return pc but we do not care about that
1379 // since we return a continuation to the deopt_blob below.
1380 JavaThread* thread = JavaThread::current();
1381 RegisterMap reg_map(thread, UseBiasedLocking);
1382 frame runtime_frame = thread->last_frame();
1383 frame caller_frame = runtime_frame.sender(®_map);
1384 assert(caller_frame.cb()->as_compiled_method_or_null() == cm, "expect top frame compiled method");
1385 Deoptimization::deoptimize(thread, caller_frame, ®_map, Deoptimization::Reason_not_compiled_exception_handler);
1386
1387 MethodData* trap_mdo = get_method_data(thread, cm->method(), true);
1388 if (trap_mdo != NULL) {
1389 trap_mdo->inc_trap_count(Deoptimization::Reason_not_compiled_exception_handler);
1390 }
1391
1392 return SharedRuntime::deopt_blob()->unpack_with_exception_in_tls();
1393 }
1394 #endif
1395
1396 void Deoptimization::deoptimize_frame_internal(JavaThread* thread, intptr_t* id, DeoptReason reason) {
1397 assert(thread == Thread::current() || SafepointSynchronize::is_at_safepoint(),
1398 "can only deoptimize other thread at a safepoint");
1399 // Compute frame and register map based on thread and sp.
1400 RegisterMap reg_map(thread, UseBiasedLocking);
1401 frame fr = thread->last_frame();
1402 while (fr.id() != id) {
1403 fr = fr.sender(®_map);
1404 }
1405 deoptimize(thread, fr, ®_map, reason);
1406 }
1407
1408
1409 void Deoptimization::deoptimize_frame(JavaThread* thread, intptr_t* id, DeoptReason reason) {
1410 if (thread == Thread::current()) {
1411 Deoptimization::deoptimize_frame_internal(thread, id, reason);
1412 } else {
1413 VM_DeoptimizeFrame deopt(thread, id, reason);
1414 VMThread::execute(&deopt);
1415 }
1416 }
1417
1418 void Deoptimization::deoptimize_frame(JavaThread* thread, intptr_t* id) {
1419 deoptimize_frame(thread, id, Reason_constraint);
1420 }
1421
1422 // JVMTI PopFrame support
1423 JRT_LEAF(void, Deoptimization::popframe_preserve_args(JavaThread* thread, int bytes_to_save, void* start_address))
1424 {
1425 thread->popframe_preserve_args(in_ByteSize(bytes_to_save), start_address);
1426 }
1427 JRT_END
1428
1429 MethodData*
1430 Deoptimization::get_method_data(JavaThread* thread, const methodHandle& m,
1431 bool create_if_missing) {
1432 Thread* THREAD = thread;
1433 MethodData* mdo = m()->method_data();
1434 if (mdo == NULL && create_if_missing && !HAS_PENDING_EXCEPTION) {
1435 // Build an MDO. Ignore errors like OutOfMemory;
1436 // that simply means we won't have an MDO to update.
1437 Method::build_interpreter_method_data(m, THREAD);
1438 if (HAS_PENDING_EXCEPTION) {
1439 assert((PENDING_EXCEPTION->is_a(SystemDictionary::OutOfMemoryError_klass())), "we expect only an OOM error here");
1440 CLEAR_PENDING_EXCEPTION;
1441 }
1442 mdo = m()->method_data();
1443 }
1444 return mdo;
1445 }
1446
1447 #if COMPILER2_OR_JVMCI
1448 void Deoptimization::load_class_by_index(const constantPoolHandle& constant_pool, int index, TRAPS) {
1449 // in case of an unresolved klass entry, load the class.
1450 if (constant_pool->tag_at(index).is_unresolved_klass()) {
1451 Klass* tk = constant_pool->klass_at_ignore_error(index, CHECK);
1452 return;
1453 }
1454
1455 if (!constant_pool->tag_at(index).is_symbol()) return;
1456
1457 Handle class_loader (THREAD, constant_pool->pool_holder()->class_loader());
1458 Symbol* symbol = constant_pool->symbol_at(index);
1459
1460 // class name?
1461 if (symbol->byte_at(0) != '(') {
1462 Handle protection_domain (THREAD, constant_pool->pool_holder()->protection_domain());
1463 SystemDictionary::resolve_or_null(symbol, class_loader, protection_domain, CHECK);
1464 return;
1465 }
1466
1467 // then it must be a signature!
1468 ResourceMark rm(THREAD);
1469 for (SignatureStream ss(symbol); !ss.is_done(); ss.next()) {
1470 if (ss.is_object()) {
1471 Symbol* class_name = ss.as_symbol(CHECK);
1472 Handle protection_domain (THREAD, constant_pool->pool_holder()->protection_domain());
1473 SystemDictionary::resolve_or_null(class_name, class_loader, protection_domain, CHECK);
1474 }
1475 }
1476 }
1477
1478
1479 void Deoptimization::load_class_by_index(const constantPoolHandle& constant_pool, int index) {
1480 EXCEPTION_MARK;
1481 load_class_by_index(constant_pool, index, THREAD);
1482 if (HAS_PENDING_EXCEPTION) {
1483 // Exception happened during classloading. We ignore the exception here, since it
1484 // is going to be rethrown since the current activation is going to be deoptimized and
1485 // the interpreter will re-execute the bytecode.
1486 CLEAR_PENDING_EXCEPTION;
1487 // Class loading called java code which may have caused a stack
1488 // overflow. If the exception was thrown right before the return
1489 // to the runtime the stack is no longer guarded. Reguard the
1490 // stack otherwise if we return to the uncommon trap blob and the
1491 // stack bang causes a stack overflow we crash.
1492 assert(THREAD->is_Java_thread(), "only a java thread can be here");
1493 JavaThread* thread = (JavaThread*)THREAD;
1494 bool guard_pages_enabled = thread->stack_guards_enabled();
1495 if (!guard_pages_enabled) guard_pages_enabled = thread->reguard_stack();
1496 assert(guard_pages_enabled, "stack banging in uncommon trap blob may cause crash");
1497 }
1498 }
1499
1500 JRT_ENTRY(void, Deoptimization::uncommon_trap_inner(JavaThread* thread, jint trap_request)) {
1501 HandleMark hm;
1502
1503 // uncommon_trap() is called at the beginning of the uncommon trap
1504 // handler. Note this fact before we start generating temporary frames
1505 // that can confuse an asynchronous stack walker. This counter is
1506 // decremented at the end of unpack_frames().
1507 thread->inc_in_deopt_handler();
1508
1509 // We need to update the map if we have biased locking.
1510 #if INCLUDE_JVMCI
1511 // JVMCI might need to get an exception from the stack, which in turn requires the register map to be valid
1512 RegisterMap reg_map(thread, true);
1513 #else
1514 RegisterMap reg_map(thread, UseBiasedLocking);
1515 #endif
1516 frame stub_frame = thread->last_frame();
1517 frame fr = stub_frame.sender(®_map);
1518 // Make sure the calling nmethod is not getting deoptimized and removed
1519 // before we are done with it.
1520 nmethodLocker nl(fr.pc());
1521
1522 // Log a message
1523 Events::log(thread, "Uncommon trap: trap_request=" PTR32_FORMAT " fr.pc=" INTPTR_FORMAT " relative=" INTPTR_FORMAT,
1524 trap_request, p2i(fr.pc()), fr.pc() - fr.cb()->code_begin());
1525
1526 {
1527 ResourceMark rm;
1528
1529 // Revoke biases of any monitors in the frame to ensure we can migrate them
1530 revoke_biases_of_monitors(thread, fr, ®_map);
1531
1532 DeoptReason reason = trap_request_reason(trap_request);
1533 DeoptAction action = trap_request_action(trap_request);
1534 #if INCLUDE_JVMCI
1535 int debug_id = trap_request_debug_id(trap_request);
1536 #endif
1537 jint unloaded_class_index = trap_request_index(trap_request); // CP idx or -1
1538
1539 vframe* vf = vframe::new_vframe(&fr, ®_map, thread);
1540 compiledVFrame* cvf = compiledVFrame::cast(vf);
1541
1542 CompiledMethod* nm = cvf->code();
1543
1544 ScopeDesc* trap_scope = cvf->scope();
1545
1546 if (TraceDeoptimization) {
1547 ttyLocker ttyl;
1548 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()
1549 #if INCLUDE_JVMCI
1550 , debug_id
1551 #endif
1552 );
1553 }
1554
1555 methodHandle trap_method = trap_scope->method();
1556 int trap_bci = trap_scope->bci();
1557 #if INCLUDE_JVMCI
1558 oop speculation = thread->pending_failed_speculation();
1559 if (nm->is_compiled_by_jvmci()) {
1560 if (speculation != NULL) {
1561 oop speculation_log = nm->as_nmethod()->speculation_log();
1562 if (speculation_log != NULL) {
1563 if (TraceDeoptimization || TraceUncollectedSpeculations) {
1564 if (HotSpotSpeculationLog::lastFailed(speculation_log) != NULL) {
1565 tty->print_cr("A speculation that was not collected by the compiler is being overwritten");
1566 }
1567 }
1568 if (TraceDeoptimization) {
1569 tty->print_cr("Saving speculation to speculation log");
1570 }
1571 HotSpotSpeculationLog::set_lastFailed(speculation_log, speculation);
1572 } else {
1573 if (TraceDeoptimization) {
1574 tty->print_cr("Speculation present but no speculation log");
1575 }
1576 }
1577 thread->set_pending_failed_speculation(NULL);
1578 } else {
1579 if (TraceDeoptimization) {
1580 tty->print_cr("No speculation");
1581 }
1582 }
1583 } else {
1584 assert(speculation == NULL, "There should not be a speculation for method compiled by non-JVMCI compilers");
1585 }
1586
1587 if (trap_bci == SynchronizationEntryBCI) {
1588 trap_bci = 0;
1589 thread->set_pending_monitorenter(true);
1590 }
1591
1592 if (reason == Deoptimization::Reason_transfer_to_interpreter) {
1593 thread->set_pending_transfer_to_interpreter(true);
1594 }
1595 #endif
1596
1597 Bytecodes::Code trap_bc = trap_method->java_code_at(trap_bci);
1598 // Record this event in the histogram.
1599 gather_statistics(reason, action, trap_bc);
1600
1601 // Ensure that we can record deopt. history:
1602 // Need MDO to record RTM code generation state.
1603 bool create_if_missing = ProfileTraps || UseCodeAging RTM_OPT_ONLY( || UseRTMLocking );
1604
1605 methodHandle profiled_method;
1606 #if INCLUDE_JVMCI
1607 if (nm->is_compiled_by_jvmci()) {
1608 profiled_method = nm->method();
1609 } else {
1610 profiled_method = trap_method;
1611 }
1612 #else
1613 profiled_method = trap_method;
1614 #endif
1615
1616 MethodData* trap_mdo =
1617 get_method_data(thread, profiled_method, create_if_missing);
1618
1619 // Log a message
1620 Events::log_deopt_message(thread, "Uncommon trap: reason=%s action=%s pc=" INTPTR_FORMAT " method=%s @ %d %s",
1621 trap_reason_name(reason), trap_action_name(action), p2i(fr.pc()),
1622 trap_method->name_and_sig_as_C_string(), trap_bci, nm->compiler_name());
1623
1624 // Print a bunch of diagnostics, if requested.
1625 if (TraceDeoptimization || LogCompilation) {
1626 ResourceMark rm;
1627 ttyLocker ttyl;
1628 char buf[100];
1629 if (xtty != NULL) {
1630 xtty->begin_head("uncommon_trap thread='" UINTX_FORMAT "' %s",
1631 os::current_thread_id(),
1632 format_trap_request(buf, sizeof(buf), trap_request));
1633 nm->log_identity(xtty);
1634 }
1635 Symbol* class_name = NULL;
1636 bool unresolved = false;
1637 if (unloaded_class_index >= 0) {
1638 constantPoolHandle constants (THREAD, trap_method->constants());
1639 if (constants->tag_at(unloaded_class_index).is_unresolved_klass()) {
1640 class_name = constants->klass_name_at(unloaded_class_index);
1641 unresolved = true;
1642 if (xtty != NULL)
1643 xtty->print(" unresolved='1'");
1644 } else if (constants->tag_at(unloaded_class_index).is_symbol()) {
1645 class_name = constants->symbol_at(unloaded_class_index);
1646 }
1647 if (xtty != NULL)
1648 xtty->name(class_name);
1649 }
1650 if (xtty != NULL && trap_mdo != NULL && (int)reason < (int)MethodData::_trap_hist_limit) {
1651 // Dump the relevant MDO state.
1652 // This is the deopt count for the current reason, any previous
1653 // reasons or recompiles seen at this point.
1654 int dcnt = trap_mdo->trap_count(reason);
1655 if (dcnt != 0)
1656 xtty->print(" count='%d'", dcnt);
1657 ProfileData* pdata = trap_mdo->bci_to_data(trap_bci);
1658 int dos = (pdata == NULL)? 0: pdata->trap_state();
1659 if (dos != 0) {
1660 xtty->print(" state='%s'", format_trap_state(buf, sizeof(buf), dos));
1661 if (trap_state_is_recompiled(dos)) {
1662 int recnt2 = trap_mdo->overflow_recompile_count();
1663 if (recnt2 != 0)
1664 xtty->print(" recompiles2='%d'", recnt2);
1665 }
1666 }
1667 }
1668 if (xtty != NULL) {
1669 xtty->stamp();
1670 xtty->end_head();
1671 }
1672 if (TraceDeoptimization) { // make noise on the tty
1673 tty->print("Uncommon trap occurred in");
1674 nm->method()->print_short_name(tty);
1675 tty->print(" compiler=%s compile_id=%d", nm->compiler_name(), nm->compile_id());
1676 #if INCLUDE_JVMCI
1677 if (nm->is_nmethod()) {
1678 char* installed_code_name = nm->as_nmethod()->jvmci_installed_code_name(buf, sizeof(buf));
1679 if (installed_code_name != NULL) {
1680 tty->print(" (JVMCI: installed code name=%s) ", installed_code_name);
1681 }
1682 }
1683 #endif
1684 tty->print(" (@" INTPTR_FORMAT ") thread=" UINTX_FORMAT " reason=%s action=%s unloaded_class_index=%d" JVMCI_ONLY(" debug_id=%d"),
1685 p2i(fr.pc()),
1686 os::current_thread_id(),
1687 trap_reason_name(reason),
1688 trap_action_name(action),
1689 unloaded_class_index
1690 #if INCLUDE_JVMCI
1691 , debug_id
1692 #endif
1693 );
1694 if (class_name != NULL) {
1695 tty->print(unresolved ? " unresolved class: " : " symbol: ");
1696 class_name->print_symbol_on(tty);
1697 }
1698 tty->cr();
1699 }
1700 if (xtty != NULL) {
1701 // Log the precise location of the trap.
1702 for (ScopeDesc* sd = trap_scope; ; sd = sd->sender()) {
1703 xtty->begin_elem("jvms bci='%d'", sd->bci());
1704 xtty->method(sd->method());
1705 xtty->end_elem();
1706 if (sd->is_top()) break;
1707 }
1708 xtty->tail("uncommon_trap");
1709 }
1710 }
1711 // (End diagnostic printout.)
1712
1713 // Load class if necessary
1714 if (unloaded_class_index >= 0) {
1715 constantPoolHandle constants(THREAD, trap_method->constants());
1716 load_class_by_index(constants, unloaded_class_index);
1717 }
1718
1719 // Flush the nmethod if necessary and desirable.
1720 //
1721 // We need to avoid situations where we are re-flushing the nmethod
1722 // because of a hot deoptimization site. Repeated flushes at the same
1723 // point need to be detected by the compiler and avoided. If the compiler
1724 // cannot avoid them (or has a bug and "refuses" to avoid them), this
1725 // module must take measures to avoid an infinite cycle of recompilation
1726 // and deoptimization. There are several such measures:
1727 //
1728 // 1. If a recompilation is ordered a second time at some site X
1729 // and for the same reason R, the action is adjusted to 'reinterpret',
1730 // to give the interpreter time to exercise the method more thoroughly.
1731 // If this happens, the method's overflow_recompile_count is incremented.
1732 //
1733 // 2. If the compiler fails to reduce the deoptimization rate, then
1734 // the method's overflow_recompile_count will begin to exceed the set
1735 // limit PerBytecodeRecompilationCutoff. If this happens, the action
1736 // is adjusted to 'make_not_compilable', and the method is abandoned
1737 // to the interpreter. This is a performance hit for hot methods,
1738 // but is better than a disastrous infinite cycle of recompilations.
1739 // (Actually, only the method containing the site X is abandoned.)
1740 //
1741 // 3. In parallel with the previous measures, if the total number of
1742 // recompilations of a method exceeds the much larger set limit
1743 // PerMethodRecompilationCutoff, the method is abandoned.
1744 // This should only happen if the method is very large and has
1745 // many "lukewarm" deoptimizations. The code which enforces this
1746 // limit is elsewhere (class nmethod, class Method).
1747 //
1748 // Note that the per-BCI 'is_recompiled' bit gives the compiler one chance
1749 // to recompile at each bytecode independently of the per-BCI cutoff.
1750 //
1751 // The decision to update code is up to the compiler, and is encoded
1752 // in the Action_xxx code. If the compiler requests Action_none
1753 // no trap state is changed, no compiled code is changed, and the
1754 // computation suffers along in the interpreter.
1755 //
1756 // The other action codes specify various tactics for decompilation
1757 // and recompilation. Action_maybe_recompile is the loosest, and
1758 // allows the compiled code to stay around until enough traps are seen,
1759 // and until the compiler gets around to recompiling the trapping method.
1760 //
1761 // The other actions cause immediate removal of the present code.
1762
1763 // Traps caused by injected profile shouldn't pollute trap counts.
1764 bool injected_profile_trap = trap_method->has_injected_profile() &&
1765 (reason == Reason_intrinsic || reason == Reason_unreached);
1766
1767 bool update_trap_state = (reason != Reason_tenured) && !injected_profile_trap;
1768 bool make_not_entrant = false;
1769 bool make_not_compilable = false;
1770 bool reprofile = false;
1771 switch (action) {
1772 case Action_none:
1773 // Keep the old code.
1774 update_trap_state = false;
1775 break;
1776 case Action_maybe_recompile:
1777 // Do not need to invalidate the present code, but we can
1778 // initiate another
1779 // Start compiler without (necessarily) invalidating the nmethod.
1780 // The system will tolerate the old code, but new code should be
1781 // generated when possible.
1782 break;
1783 case Action_reinterpret:
1784 // Go back into the interpreter for a while, and then consider
1785 // recompiling form scratch.
1786 make_not_entrant = true;
1787 // Reset invocation counter for outer most method.
1788 // This will allow the interpreter to exercise the bytecodes
1789 // for a while before recompiling.
1790 // By contrast, Action_make_not_entrant is immediate.
1791 //
1792 // Note that the compiler will track null_check, null_assert,
1793 // range_check, and class_check events and log them as if they
1794 // had been traps taken from compiled code. This will update
1795 // the MDO trap history so that the next compilation will
1796 // properly detect hot trap sites.
1797 reprofile = true;
1798 break;
1799 case Action_make_not_entrant:
1800 // Request immediate recompilation, and get rid of the old code.
1801 // Make them not entrant, so next time they are called they get
1802 // recompiled. Unloaded classes are loaded now so recompile before next
1803 // time they are called. Same for uninitialized. The interpreter will
1804 // link the missing class, if any.
1805 make_not_entrant = true;
1806 break;
1807 case Action_make_not_compilable:
1808 // Give up on compiling this method at all.
1809 make_not_entrant = true;
1810 make_not_compilable = true;
1811 break;
1812 default:
1813 ShouldNotReachHere();
1814 }
1815
1816 // Setting +ProfileTraps fixes the following, on all platforms:
1817 // 4852688: ProfileInterpreter is off by default for ia64. The result is
1818 // infinite heroic-opt-uncommon-trap/deopt/recompile cycles, since the
1819 // recompile relies on a MethodData* to record heroic opt failures.
1820
1821 // Whether the interpreter is producing MDO data or not, we also need
1822 // to use the MDO to detect hot deoptimization points and control
1823 // aggressive optimization.
1824 bool inc_recompile_count = false;
1825 ProfileData* pdata = NULL;
1826 if (ProfileTraps && !is_client_compilation_mode_vm() && update_trap_state && trap_mdo != NULL) {
1827 assert(trap_mdo == get_method_data(thread, profiled_method, false), "sanity");
1828 uint this_trap_count = 0;
1829 bool maybe_prior_trap = false;
1830 bool maybe_prior_recompile = false;
1831 pdata = query_update_method_data(trap_mdo, trap_bci, reason, true,
1832 #if INCLUDE_JVMCI
1833 nm->is_compiled_by_jvmci() && nm->is_osr_method(),
1834 #endif
1835 nm->method(),
1836 //outputs:
1837 this_trap_count,
1838 maybe_prior_trap,
1839 maybe_prior_recompile);
1840 // Because the interpreter also counts null, div0, range, and class
1841 // checks, these traps from compiled code are double-counted.
1842 // This is harmless; it just means that the PerXTrapLimit values
1843 // are in effect a little smaller than they look.
1844
1845 DeoptReason per_bc_reason = reason_recorded_per_bytecode_if_any(reason);
1846 if (per_bc_reason != Reason_none) {
1847 // Now take action based on the partially known per-BCI history.
1848 if (maybe_prior_trap
1849 && this_trap_count >= (uint)PerBytecodeTrapLimit) {
1850 // If there are too many traps at this BCI, force a recompile.
1851 // This will allow the compiler to see the limit overflow, and
1852 // take corrective action, if possible. The compiler generally
1853 // does not use the exact PerBytecodeTrapLimit value, but instead
1854 // changes its tactics if it sees any traps at all. This provides
1855 // a little hysteresis, delaying a recompile until a trap happens
1856 // several times.
1857 //
1858 // Actually, since there is only one bit of counter per BCI,
1859 // the possible per-BCI counts are {0,1,(per-method count)}.
1860 // This produces accurate results if in fact there is only
1861 // one hot trap site, but begins to get fuzzy if there are
1862 // many sites. For example, if there are ten sites each
1863 // trapping two or more times, they each get the blame for
1864 // all of their traps.
1865 make_not_entrant = true;
1866 }
1867
1868 // Detect repeated recompilation at the same BCI, and enforce a limit.
1869 if (make_not_entrant && maybe_prior_recompile) {
1870 // More than one recompile at this point.
1871 inc_recompile_count = maybe_prior_trap;
1872 }
1873 } else {
1874 // For reasons which are not recorded per-bytecode, we simply
1875 // force recompiles unconditionally.
1876 // (Note that PerMethodRecompilationCutoff is enforced elsewhere.)
1877 make_not_entrant = true;
1878 }
1879
1880 // Go back to the compiler if there are too many traps in this method.
1881 if (this_trap_count >= per_method_trap_limit(reason)) {
1882 // If there are too many traps in this method, force a recompile.
1883 // This will allow the compiler to see the limit overflow, and
1884 // take corrective action, if possible.
1885 // (This condition is an unlikely backstop only, because the
1886 // PerBytecodeTrapLimit is more likely to take effect first,
1887 // if it is applicable.)
1888 make_not_entrant = true;
1889 }
1890
1891 // Here's more hysteresis: If there has been a recompile at
1892 // this trap point already, run the method in the interpreter
1893 // for a while to exercise it more thoroughly.
1894 if (make_not_entrant && maybe_prior_recompile && maybe_prior_trap) {
1895 reprofile = true;
1896 }
1897 }
1898
1899 // Take requested actions on the method:
1900
1901 // Recompile
1902 if (make_not_entrant) {
1903 if (!nm->make_not_entrant()) {
1904 return; // the call did not change nmethod's state
1905 }
1906
1907 if (pdata != NULL) {
1908 // Record the recompilation event, if any.
1909 int tstate0 = pdata->trap_state();
1910 int tstate1 = trap_state_set_recompiled(tstate0, true);
1911 if (tstate1 != tstate0)
1912 pdata->set_trap_state(tstate1);
1913 }
1914
1915 #if INCLUDE_RTM_OPT
1916 // Restart collecting RTM locking abort statistic if the method
1917 // is recompiled for a reason other than RTM state change.
1918 // Assume that in new recompiled code the statistic could be different,
1919 // for example, due to different inlining.
1920 if ((reason != Reason_rtm_state_change) && (trap_mdo != NULL) &&
1921 UseRTMDeopt && (nm->as_nmethod()->rtm_state() != ProfileRTM)) {
1922 trap_mdo->atomic_set_rtm_state(ProfileRTM);
1923 }
1924 #endif
1925 // For code aging we count traps separately here, using make_not_entrant()
1926 // as a guard against simultaneous deopts in multiple threads.
1927 if (reason == Reason_tenured && trap_mdo != NULL) {
1928 trap_mdo->inc_tenure_traps();
1929 }
1930 }
1931
1932 if (inc_recompile_count) {
1933 trap_mdo->inc_overflow_recompile_count();
1934 if ((uint)trap_mdo->overflow_recompile_count() >
1935 (uint)PerBytecodeRecompilationCutoff) {
1936 // Give up on the method containing the bad BCI.
1937 if (trap_method() == nm->method()) {
1938 make_not_compilable = true;
1939 } else {
1940 trap_method->set_not_compilable(CompLevel_full_optimization, true, "overflow_recompile_count > PerBytecodeRecompilationCutoff");
1941 // But give grace to the enclosing nm->method().
1942 }
1943 }
1944 }
1945
1946 // Reprofile
1947 if (reprofile) {
1948 CompilationPolicy::policy()->reprofile(trap_scope, nm->is_osr_method());
1949 }
1950
1951 // Give up compiling
1952 if (make_not_compilable && !nm->method()->is_not_compilable(CompLevel_full_optimization)) {
1953 assert(make_not_entrant, "consistent");
1954 nm->method()->set_not_compilable(CompLevel_full_optimization);
1955 }
1956
1957 } // Free marked resources
1958
1959 }
1960 JRT_END
1961
1962 ProfileData*
1963 Deoptimization::query_update_method_data(MethodData* trap_mdo,
1964 int trap_bci,
1965 Deoptimization::DeoptReason reason,
1966 bool update_total_trap_count,
1967 #if INCLUDE_JVMCI
1968 bool is_osr,
1969 #endif
1970 Method* compiled_method,
1971 //outputs:
1972 uint& ret_this_trap_count,
1973 bool& ret_maybe_prior_trap,
1974 bool& ret_maybe_prior_recompile) {
1975 bool maybe_prior_trap = false;
1976 bool maybe_prior_recompile = false;
1977 uint this_trap_count = 0;
1978 if (update_total_trap_count) {
1979 uint idx = reason;
1980 #if INCLUDE_JVMCI
1981 if (is_osr) {
1982 idx += Reason_LIMIT;
1983 }
1984 #endif
1985 uint prior_trap_count = trap_mdo->trap_count(idx);
1986 this_trap_count = trap_mdo->inc_trap_count(idx);
1987
1988 // If the runtime cannot find a place to store trap history,
1989 // it is estimated based on the general condition of the method.
1990 // If the method has ever been recompiled, or has ever incurred
1991 // a trap with the present reason , then this BCI is assumed
1992 // (pessimistically) to be the culprit.
1993 maybe_prior_trap = (prior_trap_count != 0);
1994 maybe_prior_recompile = (trap_mdo->decompile_count() != 0);
1995 }
1996 ProfileData* pdata = NULL;
1997
1998
1999 // For reasons which are recorded per bytecode, we check per-BCI data.
2000 DeoptReason per_bc_reason = reason_recorded_per_bytecode_if_any(reason);
2001 assert(per_bc_reason != Reason_none || update_total_trap_count, "must be");
2002 if (per_bc_reason != Reason_none) {
2003 // Find the profile data for this BCI. If there isn't one,
2004 // try to allocate one from the MDO's set of spares.
2005 // This will let us detect a repeated trap at this point.
2006 pdata = trap_mdo->allocate_bci_to_data(trap_bci, reason_is_speculate(reason) ? compiled_method : NULL);
2007
2008 if (pdata != NULL) {
2009 if (reason_is_speculate(reason) && !pdata->is_SpeculativeTrapData()) {
2010 if (LogCompilation && xtty != NULL) {
2011 ttyLocker ttyl;
2012 // no more room for speculative traps in this MDO
2013 xtty->elem("speculative_traps_oom");
2014 }
2015 }
2016 // Query the trap state of this profile datum.
2017 int tstate0 = pdata->trap_state();
2018 if (!trap_state_has_reason(tstate0, per_bc_reason))
2019 maybe_prior_trap = false;
2020 if (!trap_state_is_recompiled(tstate0))
2021 maybe_prior_recompile = false;
2022
2023 // Update the trap state of this profile datum.
2024 int tstate1 = tstate0;
2025 // Record the reason.
2026 tstate1 = trap_state_add_reason(tstate1, per_bc_reason);
2027 // Store the updated state on the MDO, for next time.
2028 if (tstate1 != tstate0)
2029 pdata->set_trap_state(tstate1);
2030 } else {
2031 if (LogCompilation && xtty != NULL) {
2032 ttyLocker ttyl;
2033 // Missing MDP? Leave a small complaint in the log.
2034 xtty->elem("missing_mdp bci='%d'", trap_bci);
2035 }
2036 }
2037 }
2038
2039 // Return results:
2040 ret_this_trap_count = this_trap_count;
2041 ret_maybe_prior_trap = maybe_prior_trap;
2042 ret_maybe_prior_recompile = maybe_prior_recompile;
2043 return pdata;
2044 }
2045
2046 void
2047 Deoptimization::update_method_data_from_interpreter(MethodData* trap_mdo, int trap_bci, int reason) {
2048 ResourceMark rm;
2049 // Ignored outputs:
2050 uint ignore_this_trap_count;
2051 bool ignore_maybe_prior_trap;
2052 bool ignore_maybe_prior_recompile;
2053 assert(!reason_is_speculate(reason), "reason speculate only used by compiler");
2054 // JVMCI uses the total counts to determine if deoptimizations are happening too frequently -> do not adjust total counts
2055 bool update_total_counts = JVMCI_ONLY(false) NOT_JVMCI(true);
2056 query_update_method_data(trap_mdo, trap_bci,
2057 (DeoptReason)reason,
2058 update_total_counts,
2059 #if INCLUDE_JVMCI
2060 false,
2061 #endif
2062 NULL,
2063 ignore_this_trap_count,
2064 ignore_maybe_prior_trap,
2065 ignore_maybe_prior_recompile);
2066 }
2067
2068 Deoptimization::UnrollBlock* Deoptimization::uncommon_trap(JavaThread* thread, jint trap_request, jint exec_mode) {
2069 if (TraceDeoptimization) {
2070 tty->print("Uncommon trap ");
2071 }
2072 // Still in Java no safepoints
2073 {
2074 // This enters VM and may safepoint
2075 uncommon_trap_inner(thread, trap_request);
2076 }
2077 return fetch_unroll_info_helper(thread, exec_mode);
2078 }
2079
2080 // Local derived constants.
2081 // Further breakdown of DataLayout::trap_state, as promised by DataLayout.
2082 const int DS_REASON_MASK = DataLayout::trap_mask >> 1;
2083 const int DS_RECOMPILE_BIT = DataLayout::trap_mask - DS_REASON_MASK;
2084
2085 //---------------------------trap_state_reason---------------------------------
2086 Deoptimization::DeoptReason
2087 Deoptimization::trap_state_reason(int trap_state) {
2088 // This assert provides the link between the width of DataLayout::trap_bits
2089 // and the encoding of "recorded" reasons. It ensures there are enough
2090 // bits to store all needed reasons in the per-BCI MDO profile.
2091 assert(DS_REASON_MASK >= Reason_RECORDED_LIMIT, "enough bits");
2092 int recompile_bit = (trap_state & DS_RECOMPILE_BIT);
2093 trap_state -= recompile_bit;
2094 if (trap_state == DS_REASON_MASK) {
2095 return Reason_many;
2096 } else {
2097 assert((int)Reason_none == 0, "state=0 => Reason_none");
2098 return (DeoptReason)trap_state;
2099 }
2100 }
2101 //-------------------------trap_state_has_reason-------------------------------
2102 int Deoptimization::trap_state_has_reason(int trap_state, int reason) {
2103 assert(reason_is_recorded_per_bytecode((DeoptReason)reason), "valid reason");
2104 assert(DS_REASON_MASK >= Reason_RECORDED_LIMIT, "enough bits");
2105 int recompile_bit = (trap_state & DS_RECOMPILE_BIT);
2106 trap_state -= recompile_bit;
2107 if (trap_state == DS_REASON_MASK) {
2108 return -1; // true, unspecifically (bottom of state lattice)
2109 } else if (trap_state == reason) {
2110 return 1; // true, definitely
2111 } else if (trap_state == 0) {
2112 return 0; // false, definitely (top of state lattice)
2113 } else {
2114 return 0; // false, definitely
2115 }
2116 }
2117 //-------------------------trap_state_add_reason-------------------------------
2118 int Deoptimization::trap_state_add_reason(int trap_state, int reason) {
2119 assert(reason_is_recorded_per_bytecode((DeoptReason)reason) || reason == Reason_many, "valid reason");
2120 int recompile_bit = (trap_state & DS_RECOMPILE_BIT);
2121 trap_state -= recompile_bit;
2122 if (trap_state == DS_REASON_MASK) {
2123 return trap_state + recompile_bit; // already at state lattice bottom
2124 } else if (trap_state == reason) {
2125 return trap_state + recompile_bit; // the condition is already true
2126 } else if (trap_state == 0) {
2127 return reason + recompile_bit; // no condition has yet been true
2128 } else {
2129 return DS_REASON_MASK + recompile_bit; // fall to state lattice bottom
2130 }
2131 }
2132 //-----------------------trap_state_is_recompiled------------------------------
2133 bool Deoptimization::trap_state_is_recompiled(int trap_state) {
2134 return (trap_state & DS_RECOMPILE_BIT) != 0;
2135 }
2136 //-----------------------trap_state_set_recompiled-----------------------------
2137 int Deoptimization::trap_state_set_recompiled(int trap_state, bool z) {
2138 if (z) return trap_state | DS_RECOMPILE_BIT;
2139 else return trap_state & ~DS_RECOMPILE_BIT;
2140 }
2141 //---------------------------format_trap_state---------------------------------
2142 // This is used for debugging and diagnostics, including LogFile output.
2143 const char* Deoptimization::format_trap_state(char* buf, size_t buflen,
2144 int trap_state) {
2145 assert(buflen > 0, "sanity");
2146 DeoptReason reason = trap_state_reason(trap_state);
2147 bool recomp_flag = trap_state_is_recompiled(trap_state);
2148 // Re-encode the state from its decoded components.
2149 int decoded_state = 0;
2150 if (reason_is_recorded_per_bytecode(reason) || reason == Reason_many)
2151 decoded_state = trap_state_add_reason(decoded_state, reason);
2152 if (recomp_flag)
2153 decoded_state = trap_state_set_recompiled(decoded_state, recomp_flag);
2154 // If the state re-encodes properly, format it symbolically.
2155 // Because this routine is used for debugging and diagnostics,
2156 // be robust even if the state is a strange value.
2157 size_t len;
2158 if (decoded_state != trap_state) {
2159 // Random buggy state that doesn't decode??
2160 len = jio_snprintf(buf, buflen, "#%d", trap_state);
2161 } else {
2162 len = jio_snprintf(buf, buflen, "%s%s",
2163 trap_reason_name(reason),
2164 recomp_flag ? " recompiled" : "");
2165 }
2166 return buf;
2167 }
2168
2169
2170 //--------------------------------statics--------------------------------------
2171 const char* Deoptimization::_trap_reason_name[] = {
2172 // Note: Keep this in sync. with enum DeoptReason.
2173 "none",
2174 "null_check",
2175 "null_assert" JVMCI_ONLY("_or_unreached0"),
2176 "range_check",
2177 "class_check",
2178 "array_check",
2179 "intrinsic" JVMCI_ONLY("_or_type_checked_inlining"),
2180 "bimorphic" JVMCI_ONLY("_or_optimized_type_check"),
2181 "unloaded",
2182 "uninitialized",
2183 "unreached",
2184 "unhandled",
2185 "constraint",
2186 "div0_check",
2187 "age",
2188 "predicate",
2189 "loop_limit_check",
2190 "speculate_class_check",
2191 "speculate_null_check",
2192 "speculate_null_assert",
2193 "rtm_state_change",
2194 "unstable_if",
2195 "unstable_fused_if",
2196 #if INCLUDE_JVMCI
2197 "aliasing",
2198 "transfer_to_interpreter",
2199 "not_compiled_exception_handler",
2200 "unresolved",
2201 "jsr_mismatch",
2202 #endif
2203 "tenured"
2204 };
2205 const char* Deoptimization::_trap_action_name[] = {
2206 // Note: Keep this in sync. with enum DeoptAction.
2207 "none",
2208 "maybe_recompile",
2209 "reinterpret",
2210 "make_not_entrant",
2211 "make_not_compilable"
2212 };
2213
2214 const char* Deoptimization::trap_reason_name(int reason) {
2215 // Check that every reason has a name
2216 STATIC_ASSERT(sizeof(_trap_reason_name)/sizeof(const char*) == Reason_LIMIT);
2217
2218 if (reason == Reason_many) return "many";
2219 if ((uint)reason < Reason_LIMIT)
2220 return _trap_reason_name[reason];
2221 static char buf[20];
2222 sprintf(buf, "reason%d", reason);
2223 return buf;
2224 }
2225 const char* Deoptimization::trap_action_name(int action) {
2226 // Check that every action has a name
2227 STATIC_ASSERT(sizeof(_trap_action_name)/sizeof(const char*) == Action_LIMIT);
2228
2229 if ((uint)action < Action_LIMIT)
2230 return _trap_action_name[action];
2231 static char buf[20];
2232 sprintf(buf, "action%d", action);
2233 return buf;
2234 }
2235
2236 // This is used for debugging and diagnostics, including LogFile output.
2237 const char* Deoptimization::format_trap_request(char* buf, size_t buflen,
2238 int trap_request) {
2239 jint unloaded_class_index = trap_request_index(trap_request);
2240 const char* reason = trap_reason_name(trap_request_reason(trap_request));
2241 const char* action = trap_action_name(trap_request_action(trap_request));
2242 #if INCLUDE_JVMCI
2243 int debug_id = trap_request_debug_id(trap_request);
2244 #endif
2245 size_t len;
2246 if (unloaded_class_index < 0) {
2247 len = jio_snprintf(buf, buflen, "reason='%s' action='%s'" JVMCI_ONLY(" debug_id='%d'"),
2248 reason, action
2249 #if INCLUDE_JVMCI
2250 ,debug_id
2251 #endif
2252 );
2253 } else {
2254 len = jio_snprintf(buf, buflen, "reason='%s' action='%s' index='%d'" JVMCI_ONLY(" debug_id='%d'"),
2255 reason, action, unloaded_class_index
2256 #if INCLUDE_JVMCI
2257 ,debug_id
2258 #endif
2259 );
2260 }
2261 return buf;
2262 }
2263
2264 juint Deoptimization::_deoptimization_hist
2265 [Deoptimization::Reason_LIMIT]
2266 [1 + Deoptimization::Action_LIMIT]
2267 [Deoptimization::BC_CASE_LIMIT]
2268 = {0};
2269
2270 enum {
2271 LSB_BITS = 8,
2272 LSB_MASK = right_n_bits(LSB_BITS)
2273 };
2274
2275 void Deoptimization::gather_statistics(DeoptReason reason, DeoptAction action,
2276 Bytecodes::Code bc) {
2277 assert(reason >= 0 && reason < Reason_LIMIT, "oob");
2278 assert(action >= 0 && action < Action_LIMIT, "oob");
2279 _deoptimization_hist[Reason_none][0][0] += 1; // total
2280 _deoptimization_hist[reason][0][0] += 1; // per-reason total
2281 juint* cases = _deoptimization_hist[reason][1+action];
2282 juint* bc_counter_addr = NULL;
2283 juint bc_counter = 0;
2284 // Look for an unused counter, or an exact match to this BC.
2285 if (bc != Bytecodes::_illegal) {
2286 for (int bc_case = 0; bc_case < BC_CASE_LIMIT; bc_case++) {
2287 juint* counter_addr = &cases[bc_case];
2288 juint counter = *counter_addr;
2289 if ((counter == 0 && bc_counter_addr == NULL)
2290 || (Bytecodes::Code)(counter & LSB_MASK) == bc) {
2291 // this counter is either free or is already devoted to this BC
2292 bc_counter_addr = counter_addr;
2293 bc_counter = counter | bc;
2294 }
2295 }
2296 }
2297 if (bc_counter_addr == NULL) {
2298 // Overflow, or no given bytecode.
2299 bc_counter_addr = &cases[BC_CASE_LIMIT-1];
2300 bc_counter = (*bc_counter_addr & ~LSB_MASK); // clear LSB
2301 }
2302 *bc_counter_addr = bc_counter + (1 << LSB_BITS);
2303 }
2304
2305 jint Deoptimization::total_deoptimization_count() {
2306 return _deoptimization_hist[Reason_none][0][0];
2307 }
2308
2309 jint Deoptimization::deoptimization_count(DeoptReason reason) {
2310 assert(reason >= 0 && reason < Reason_LIMIT, "oob");
2311 return _deoptimization_hist[reason][0][0];
2312 }
2313
2314 void Deoptimization::print_statistics() {
2315 juint total = total_deoptimization_count();
2316 juint account = total;
2317 if (total != 0) {
2318 ttyLocker ttyl;
2319 if (xtty != NULL) xtty->head("statistics type='deoptimization'");
2320 tty->print_cr("Deoptimization traps recorded:");
2321 #define PRINT_STAT_LINE(name, r) \
2322 tty->print_cr(" %4d (%4.1f%%) %s", (int)(r), ((r) * 100.0) / total, name);
2323 PRINT_STAT_LINE("total", total);
2324 // For each non-zero entry in the histogram, print the reason,
2325 // the action, and (if specifically known) the type of bytecode.
2326 for (int reason = 0; reason < Reason_LIMIT; reason++) {
2327 for (int action = 0; action < Action_LIMIT; action++) {
2328 juint* cases = _deoptimization_hist[reason][1+action];
2329 for (int bc_case = 0; bc_case < BC_CASE_LIMIT; bc_case++) {
2330 juint counter = cases[bc_case];
2331 if (counter != 0) {
2332 char name[1*K];
2333 Bytecodes::Code bc = (Bytecodes::Code)(counter & LSB_MASK);
2334 if (bc_case == BC_CASE_LIMIT && (int)bc == 0)
2335 bc = Bytecodes::_illegal;
2336 sprintf(name, "%s/%s/%s",
2337 trap_reason_name(reason),
2338 trap_action_name(action),
2339 Bytecodes::is_defined(bc)? Bytecodes::name(bc): "other");
2340 juint r = counter >> LSB_BITS;
2341 tty->print_cr(" %40s: " UINT32_FORMAT " (%.1f%%)", name, r, (r * 100.0) / total);
2342 account -= r;
2343 }
2344 }
2345 }
2346 }
2347 if (account != 0) {
2348 PRINT_STAT_LINE("unaccounted", account);
2349 }
2350 #undef PRINT_STAT_LINE
2351 if (xtty != NULL) xtty->tail("statistics");
2352 }
2353 }
2354 #else // COMPILER2_OR_JVMCI
2355
2356
2357 // Stubs for C1 only system.
2358 bool Deoptimization::trap_state_is_recompiled(int trap_state) {
2359 return false;
2360 }
2361
2362 const char* Deoptimization::trap_reason_name(int reason) {
2363 return "unknown";
2364 }
2365
2366 void Deoptimization::print_statistics() {
2367 // no output
2368 }
2369
2370 void
2371 Deoptimization::update_method_data_from_interpreter(MethodData* trap_mdo, int trap_bci, int reason) {
2372 // no udpate
2373 }
2374
2375 int Deoptimization::trap_state_has_reason(int trap_state, int reason) {
2376 return 0;
2377 }
2378
2379 void Deoptimization::gather_statistics(DeoptReason reason, DeoptAction action,
2380 Bytecodes::Code bc) {
2381 // no update
2382 }
2383
2384 const char* Deoptimization::format_trap_state(char* buf, size_t buflen,
2385 int trap_state) {
2386 jio_snprintf(buf, buflen, "#%d", trap_state);
2387 return buf;
2388 }
2389
2390 #endif // COMPILER2_OR_JVMCI