1 /*
2 * Copyright (c) 1997, 2015, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation.
8 *
9 * This code is distributed in the hope that it will be useful, but WITHOUT
10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
12 * version 2 for more details (a copy is included in the LICENSE file that
13 * accompanied this code).
14 *
15 * You should have received a copy of the GNU General Public License version
16 * 2 along with this work; if not, write to the Free Software Foundation,
17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
18 *
19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
20 * or visit www.oracle.com if you need additional information or have any
21 * questions.
22 *
23 */
24
25 #include "precompiled.hpp"
26 #include "classfile/systemDictionary.hpp"
27 #include "code/codeCache.hpp"
28 #include "code/debugInfoRec.hpp"
29 #include "code/nmethod.hpp"
30 #include "code/pcDesc.hpp"
31 #include "code/scopeDesc.hpp"
32 #include "interpreter/bytecode.hpp"
33 #include "interpreter/interpreter.hpp"
34 #include "interpreter/oopMapCache.hpp"
35 #include "memory/allocation.inline.hpp"
36 #include "memory/oopFactory.hpp"
37 #include "memory/resourceArea.hpp"
38 #include "oops/method.hpp"
39 #include "oops/oop.inline.hpp"
40 #include "oops/verifyOopClosure.hpp"
41 #include "prims/jvmtiThreadState.hpp"
42 #include "runtime/biasedLocking.hpp"
43 #include "runtime/compilationPolicy.hpp"
44 #include "runtime/deoptimization.hpp"
45 #include "runtime/interfaceSupport.hpp"
46 #include "runtime/sharedRuntime.hpp"
47 #include "runtime/signature.hpp"
48 #include "runtime/stubRoutines.hpp"
49 #include "runtime/thread.hpp"
50 #include "runtime/vframe.hpp"
51 #include "runtime/vframeArray.hpp"
52 #include "runtime/vframe_hp.hpp"
53 #include "utilities/events.hpp"
54 #include "utilities/xmlstream.hpp"
55
56 PRAGMA_FORMAT_MUTE_WARNINGS_FOR_GCC
57
58 bool DeoptimizationMarker::_is_active = false;
59
60 Deoptimization::UnrollBlock::UnrollBlock(int size_of_deoptimized_frame,
61 int caller_adjustment,
62 int caller_actual_parameters,
63 int number_of_frames,
64 intptr_t* frame_sizes,
65 address* frame_pcs,
66 BasicType return_type) {
67 _size_of_deoptimized_frame = size_of_deoptimized_frame;
68 _caller_adjustment = caller_adjustment;
69 _caller_actual_parameters = caller_actual_parameters;
70 _number_of_frames = number_of_frames;
71 _frame_sizes = frame_sizes;
72 _frame_pcs = frame_pcs;
73 _register_block = NEW_C_HEAP_ARRAY(intptr_t, RegisterMap::reg_count * 2, mtCompiler);
74 _return_type = return_type;
75 _initial_info = 0;
76 // PD (x86 only)
77 _counter_temp = 0;
78 _unpack_kind = 0;
79 _sender_sp_temp = 0;
80
81 _total_frame_sizes = size_of_frames();
82 }
83
84
85 Deoptimization::UnrollBlock::~UnrollBlock() {
86 FREE_C_HEAP_ARRAY(intptr_t, _frame_sizes);
87 FREE_C_HEAP_ARRAY(intptr_t, _frame_pcs);
88 FREE_C_HEAP_ARRAY(intptr_t, _register_block);
89 }
90
91
92 intptr_t* Deoptimization::UnrollBlock::value_addr_at(int register_number) const {
93 assert(register_number < RegisterMap::reg_count, "checking register number");
94 return &_register_block[register_number * 2];
95 }
96
97
98
99 int Deoptimization::UnrollBlock::size_of_frames() const {
100 // Acount first for the adjustment of the initial frame
101 int result = _caller_adjustment;
102 for (int index = 0; index < number_of_frames(); index++) {
103 result += frame_sizes()[index];
104 }
105 return result;
106 }
107
108
109 void Deoptimization::UnrollBlock::print() {
110 ttyLocker ttyl;
111 tty->print_cr("UnrollBlock");
112 tty->print_cr(" size_of_deoptimized_frame = %d", _size_of_deoptimized_frame);
113 tty->print( " frame_sizes: ");
114 for (int index = 0; index < number_of_frames(); index++) {
115 tty->print("%d ", frame_sizes()[index]);
116 }
117 tty->cr();
118 }
119
120
121 // In order to make fetch_unroll_info work properly with escape
122 // analysis, The method was changed from JRT_LEAF to JRT_BLOCK_ENTRY and
123 // ResetNoHandleMark and HandleMark were removed from it. The actual reallocation
124 // of previously eliminated objects occurs in realloc_objects, which is
125 // called from the method fetch_unroll_info_helper below.
126 JRT_BLOCK_ENTRY(Deoptimization::UnrollBlock*, Deoptimization::fetch_unroll_info(JavaThread* thread))
127 // It is actually ok to allocate handles in a leaf method. It causes no safepoints,
128 // but makes the entry a little slower. There is however a little dance we have to
129 // do in debug mode to get around the NoHandleMark code in the JRT_LEAF macro
130
131 // fetch_unroll_info() is called at the beginning of the deoptimization
132 // handler. Note this fact before we start generating temporary frames
133 // that can confuse an asynchronous stack walker. This counter is
134 // decremented at the end of unpack_frames().
135 thread->inc_in_deopt_handler();
136
137 return fetch_unroll_info_helper(thread);
138 JRT_END
139
140
141 // This is factored, since it is both called from a JRT_LEAF (deoptimization) and a JRT_ENTRY (uncommon_trap)
142 Deoptimization::UnrollBlock* Deoptimization::fetch_unroll_info_helper(JavaThread* thread) {
143
144 // Note: there is a safepoint safety issue here. No matter whether we enter
145 // via vanilla deopt or uncommon trap we MUST NOT stop at a safepoint once
146 // the vframeArray is created.
147 //
148
149 // Allocate our special deoptimization ResourceMark
150 DeoptResourceMark* dmark = new DeoptResourceMark(thread);
151 assert(thread->deopt_mark() == NULL, "Pending deopt!");
152 thread->set_deopt_mark(dmark);
153
154 frame stub_frame = thread->last_frame(); // Makes stack walkable as side effect
155 RegisterMap map(thread, true);
156 RegisterMap dummy_map(thread, false);
157 // Now get the deoptee with a valid map
158 frame deoptee = stub_frame.sender(&map);
159 // Set the deoptee nmethod
160 assert(thread->deopt_nmethod() == NULL, "Pending deopt!");
161 thread->set_deopt_nmethod(deoptee.cb()->as_nmethod_or_null());
162
163 if (VerifyStack) {
164 thread->validate_frame_layout();
165 }
166
167 // Create a growable array of VFrames where each VFrame represents an inlined
168 // Java frame. This storage is allocated with the usual system arena.
169 assert(deoptee.is_compiled_frame(), "Wrong frame type");
170 GrowableArray<compiledVFrame*>* chunk = new GrowableArray<compiledVFrame*>(10);
171 vframe* vf = vframe::new_vframe(&deoptee, &map, thread);
172 while (!vf->is_top()) {
173 assert(vf->is_compiled_frame(), "Wrong frame type");
174 chunk->push(compiledVFrame::cast(vf));
175 vf = vf->sender();
176 }
177 assert(vf->is_compiled_frame(), "Wrong frame type");
178 chunk->push(compiledVFrame::cast(vf));
179
180 bool realloc_failures = false;
181
182 #ifdef COMPILER2
183 // Reallocate the non-escaping objects and restore their fields. Then
184 // relock objects if synchronization on them was eliminated.
185 if (DoEscapeAnalysis || EliminateNestedLocks) {
186 if (EliminateAllocations) {
187 assert (chunk->at(0)->scope() != NULL,"expect only compiled java frames");
188 GrowableArray<ScopeValue*>* objects = chunk->at(0)->scope()->objects();
189
190 // The flag return_oop() indicates call sites which return oop
191 // in compiled code. Such sites include java method calls,
192 // runtime calls (for example, used to allocate new objects/arrays
193 // on slow code path) and any other calls generated in compiled code.
194 // It is not guaranteed that we can get such information here only
195 // by analyzing bytecode in deoptimized frames. This is why this flag
196 // is set during method compilation (see Compile::Process_OopMap_Node()).
197 // If the previous frame was popped, we don't have a result.
198 bool save_oop_result = chunk->at(0)->scope()->return_oop() && !thread->popframe_forcing_deopt_reexecution();
199 Handle return_value;
200 if (save_oop_result) {
201 // Reallocation may trigger GC. If deoptimization happened on return from
202 // call which returns oop we need to save it since it is not in oopmap.
203 oop result = deoptee.saved_oop_result(&map);
204 assert(result == NULL || result->is_oop(), "must be oop");
205 return_value = Handle(thread, result);
206 assert(Universe::heap()->is_in_or_null(result), "must be heap pointer");
207 if (TraceDeoptimization) {
208 ttyLocker ttyl;
209 tty->print_cr("SAVED OOP RESULT " INTPTR_FORMAT " in thread " INTPTR_FORMAT, (void *)result, thread);
210 }
211 }
212 if (objects != NULL) {
213 JRT_BLOCK
214 realloc_failures = realloc_objects(thread, &deoptee, objects, THREAD);
215 JRT_END
216 reassign_fields(&deoptee, &map, objects, realloc_failures);
217 #ifndef PRODUCT
218 if (TraceDeoptimization) {
219 ttyLocker ttyl;
220 tty->print_cr("REALLOC OBJECTS in thread " INTPTR_FORMAT, thread);
221 print_objects(objects, realloc_failures);
222 }
223 #endif
224 }
225 if (save_oop_result) {
226 // Restore result.
227 deoptee.set_saved_oop_result(&map, return_value());
228 }
229 }
230 if (EliminateLocks) {
231 #ifndef PRODUCT
232 bool first = true;
233 #endif
234 for (int i = 0; i < chunk->length(); i++) {
235 compiledVFrame* cvf = chunk->at(i);
236 assert (cvf->scope() != NULL,"expect only compiled java frames");
237 GrowableArray<MonitorInfo*>* monitors = cvf->monitors();
238 if (monitors->is_nonempty()) {
239 relock_objects(monitors, thread, realloc_failures);
240 #ifndef PRODUCT
241 if (TraceDeoptimization) {
242 ttyLocker ttyl;
243 for (int j = 0; j < monitors->length(); j++) {
244 MonitorInfo* mi = monitors->at(j);
245 if (mi->eliminated()) {
246 if (first) {
247 first = false;
248 tty->print_cr("RELOCK OBJECTS in thread " INTPTR_FORMAT, thread);
249 }
250 if (mi->owner_is_scalar_replaced()) {
251 Klass* k = java_lang_Class::as_Klass(mi->owner_klass());
252 tty->print_cr(" failed reallocation for klass %s", k->external_name());
253 } else {
254 tty->print_cr(" object <" INTPTR_FORMAT "> locked", (void *)mi->owner());
255 }
256 }
257 }
258 }
259 #endif
260 }
261 }
262 }
263 }
264 #endif // COMPILER2
265 // Ensure that no safepoint is taken after pointers have been stored
266 // in fields of rematerialized objects. If a safepoint occurs from here on
267 // out the java state residing in the vframeArray will be missed.
268 No_Safepoint_Verifier no_safepoint;
269
270 vframeArray* array = create_vframeArray(thread, deoptee, &map, chunk, realloc_failures);
271 #ifdef COMPILER2
272 if (realloc_failures) {
273 pop_frames_failed_reallocs(thread, array);
274 }
275 #endif
276
277 assert(thread->vframe_array_head() == NULL, "Pending deopt!");
278 thread->set_vframe_array_head(array);
279
280 // Now that the vframeArray has been created if we have any deferred local writes
281 // added by jvmti then we can free up that structure as the data is now in the
282 // vframeArray
283
284 if (thread->deferred_locals() != NULL) {
285 GrowableArray<jvmtiDeferredLocalVariableSet*>* list = thread->deferred_locals();
286 int i = 0;
287 do {
288 // Because of inlining we could have multiple vframes for a single frame
289 // and several of the vframes could have deferred writes. Find them all.
290 if (list->at(i)->id() == array->original().id()) {
291 jvmtiDeferredLocalVariableSet* dlv = list->at(i);
292 list->remove_at(i);
293 // individual jvmtiDeferredLocalVariableSet are CHeapObj's
294 delete dlv;
295 } else {
296 i++;
297 }
298 } while ( i < list->length() );
299 if (list->length() == 0) {
300 thread->set_deferred_locals(NULL);
301 // free the list and elements back to C heap.
302 delete list;
303 }
304
305 }
306
307 #ifndef SHARK
308 // Compute the caller frame based on the sender sp of stub_frame and stored frame sizes info.
309 CodeBlob* cb = stub_frame.cb();
310 // Verify we have the right vframeArray
311 assert(cb->frame_size() >= 0, "Unexpected frame size");
312 intptr_t* unpack_sp = stub_frame.sp() + cb->frame_size();
313
314 // If the deopt call site is a MethodHandle invoke call site we have
315 // to adjust the unpack_sp.
316 nmethod* deoptee_nm = deoptee.cb()->as_nmethod_or_null();
317 if (deoptee_nm != NULL && deoptee_nm->is_method_handle_return(deoptee.pc()))
318 unpack_sp = deoptee.unextended_sp();
319
320 #ifdef ASSERT
321 assert(cb->is_deoptimization_stub() || cb->is_uncommon_trap_stub(), "just checking");
322 #endif
323 #else
324 intptr_t* unpack_sp = stub_frame.sender(&dummy_map).unextended_sp();
325 #endif // !SHARK
326
327 // This is a guarantee instead of an assert because if vframe doesn't match
328 // we will unpack the wrong deoptimized frame and wind up in strange places
329 // where it will be very difficult to figure out what went wrong. Better
330 // to die an early death here than some very obscure death later when the
331 // trail is cold.
332 // Note: on ia64 this guarantee can be fooled by frames with no memory stack
333 // in that it will fail to detect a problem when there is one. This needs
334 // more work in tiger timeframe.
335 guarantee(array->unextended_sp() == unpack_sp, "vframe_array_head must contain the vframeArray to unpack");
336
337 int number_of_frames = array->frames();
338
339 // Compute the vframes' sizes. Note that frame_sizes[] entries are ordered from outermost to innermost
340 // virtual activation, which is the reverse of the elements in the vframes array.
341 intptr_t* frame_sizes = NEW_C_HEAP_ARRAY(intptr_t, number_of_frames, mtCompiler);
342 // +1 because we always have an interpreter return address for the final slot.
343 address* frame_pcs = NEW_C_HEAP_ARRAY(address, number_of_frames + 1, mtCompiler);
344 int popframe_extra_args = 0;
345 // Create an interpreter return address for the stub to use as its return
346 // address so the skeletal frames are perfectly walkable
347 frame_pcs[number_of_frames] = Interpreter::deopt_entry(vtos, 0);
348
349 // PopFrame requires that the preserved incoming arguments from the recently-popped topmost
350 // activation be put back on the expression stack of the caller for reexecution
351 if (JvmtiExport::can_pop_frame() && thread->popframe_forcing_deopt_reexecution()) {
352 popframe_extra_args = in_words(thread->popframe_preserved_args_size_in_words());
353 }
354
355 // Find the current pc for sender of the deoptee. Since the sender may have been deoptimized
356 // itself since the deoptee vframeArray was created we must get a fresh value of the pc rather
357 // than simply use array->sender.pc(). This requires us to walk the current set of frames
358 //
359 frame deopt_sender = stub_frame.sender(&dummy_map); // First is the deoptee frame
360 deopt_sender = deopt_sender.sender(&dummy_map); // Now deoptee caller
361
362 // It's possible that the number of parameters at the call site is
363 // different than number of arguments in the callee when method
364 // handles are used. If the caller is interpreted get the real
365 // value so that the proper amount of space can be added to it's
366 // frame.
367 bool caller_was_method_handle = false;
368 if (deopt_sender.is_interpreted_frame()) {
369 methodHandle method = deopt_sender.interpreter_frame_method();
370 Bytecode_invoke cur = Bytecode_invoke_check(method, deopt_sender.interpreter_frame_bci());
371 if (cur.is_invokedynamic() || cur.is_invokehandle()) {
372 // Method handle invokes may involve fairly arbitrary chains of
373 // calls so it's impossible to know how much actual space the
374 // caller has for locals.
375 caller_was_method_handle = true;
376 }
377 }
378
379 //
380 // frame_sizes/frame_pcs[0] oldest frame (int or c2i)
381 // frame_sizes/frame_pcs[1] next oldest frame (int)
382 // frame_sizes/frame_pcs[n] youngest frame (int)
383 //
384 // Now a pc in frame_pcs is actually the return address to the frame's caller (a frame
385 // owns the space for the return address to it's caller). Confusing ain't it.
386 //
387 // The vframe array can address vframes with indices running from
388 // 0.._frames-1. Index 0 is the youngest frame and _frame - 1 is the oldest (root) frame.
389 // When we create the skeletal frames we need the oldest frame to be in the zero slot
390 // in the frame_sizes/frame_pcs so the assembly code can do a trivial walk.
391 // so things look a little strange in this loop.
392 //
393 int callee_parameters = 0;
394 int callee_locals = 0;
395 for (int index = 0; index < array->frames(); index++ ) {
396 // frame[number_of_frames - 1 ] = on_stack_size(youngest)
397 // frame[number_of_frames - 2 ] = on_stack_size(sender(youngest))
398 // frame[number_of_frames - 3 ] = on_stack_size(sender(sender(youngest)))
399 frame_sizes[number_of_frames - 1 - index] = BytesPerWord * array->element(index)->on_stack_size(callee_parameters,
400 callee_locals,
401 index == 0,
402 popframe_extra_args);
403 // This pc doesn't have to be perfect just good enough to identify the frame
404 // as interpreted so the skeleton frame will be walkable
405 // The correct pc will be set when the skeleton frame is completely filled out
406 // The final pc we store in the loop is wrong and will be overwritten below
407 frame_pcs[number_of_frames - 1 - index ] = Interpreter::deopt_entry(vtos, 0) - frame::pc_return_offset;
408
409 callee_parameters = array->element(index)->method()->size_of_parameters();
410 callee_locals = array->element(index)->method()->max_locals();
411 popframe_extra_args = 0;
412 }
413
414 // Compute whether the root vframe returns a float or double value.
415 BasicType return_type;
416 {
417 HandleMark hm;
418 methodHandle method(thread, array->element(0)->method());
419 Bytecode_invoke invoke = Bytecode_invoke_check(method, array->element(0)->bci());
420 return_type = invoke.is_valid() ? invoke.result_type() : T_ILLEGAL;
421 }
422
423 // Compute information for handling adapters and adjusting the frame size of the caller.
424 int caller_adjustment = 0;
425
426 // Compute the amount the oldest interpreter frame will have to adjust
427 // its caller's stack by. If the caller is a compiled frame then
428 // we pretend that the callee has no parameters so that the
429 // extension counts for the full amount of locals and not just
430 // locals-parms. This is because without a c2i adapter the parm
431 // area as created by the compiled frame will not be usable by
432 // the interpreter. (Depending on the calling convention there
433 // may not even be enough space).
434
435 // QQQ I'd rather see this pushed down into last_frame_adjust
436 // and have it take the sender (aka caller).
437
438 if (deopt_sender.is_compiled_frame() || caller_was_method_handle) {
439 caller_adjustment = last_frame_adjust(0, callee_locals);
440 } else if (callee_locals > callee_parameters) {
441 // The caller frame may need extending to accommodate
442 // non-parameter locals of the first unpacked interpreted frame.
443 // Compute that adjustment.
444 caller_adjustment = last_frame_adjust(callee_parameters, callee_locals);
445 }
446
447 // If the sender is deoptimized the we must retrieve the address of the handler
448 // since the frame will "magically" show the original pc before the deopt
449 // and we'd undo the deopt.
450
451 frame_pcs[0] = deopt_sender.raw_pc();
452
453 #ifndef SHARK
454 assert(CodeCache::find_blob_unsafe(frame_pcs[0]) != NULL, "bad pc");
455 #endif // SHARK
456
457 UnrollBlock* info = new UnrollBlock(array->frame_size() * BytesPerWord,
458 caller_adjustment * BytesPerWord,
459 caller_was_method_handle ? 0 : callee_parameters,
460 number_of_frames,
461 frame_sizes,
462 frame_pcs,
463 return_type);
464 // On some platforms, we need a way to pass some platform dependent
465 // information to the unpacking code so the skeletal frames come out
466 // correct (initial fp value, unextended sp, ...)
467 info->set_initial_info((intptr_t) array->sender().initial_deoptimization_info());
468
469 if (array->frames() > 1) {
470 if (VerifyStack && TraceDeoptimization) {
471 ttyLocker ttyl;
472 tty->print_cr("Deoptimizing method containing inlining");
473 }
474 }
475
476 array->set_unroll_block(info);
477 return info;
478 }
479
480 // Called to cleanup deoptimization data structures in normal case
481 // after unpacking to stack and when stack overflow error occurs
482 void Deoptimization::cleanup_deopt_info(JavaThread *thread,
483 vframeArray *array) {
484
485 // Get array if coming from exception
486 if (array == NULL) {
487 array = thread->vframe_array_head();
488 }
489 thread->set_vframe_array_head(NULL);
490
491 // Free the previous UnrollBlock
492 vframeArray* old_array = thread->vframe_array_last();
493 thread->set_vframe_array_last(array);
494
495 if (old_array != NULL) {
496 UnrollBlock* old_info = old_array->unroll_block();
497 old_array->set_unroll_block(NULL);
498 delete old_info;
499 delete old_array;
500 }
501
502 // Deallocate any resource creating in this routine and any ResourceObjs allocated
503 // inside the vframeArray (StackValueCollections)
504
505 delete thread->deopt_mark();
506 thread->set_deopt_mark(NULL);
507 thread->set_deopt_nmethod(NULL);
508
509
510 if (JvmtiExport::can_pop_frame()) {
511 #ifndef CC_INTERP
512 // Regardless of whether we entered this routine with the pending
513 // popframe condition bit set, we should always clear it now
514 thread->clear_popframe_condition();
515 #else
516 // C++ interpreter will clear has_pending_popframe when it enters
517 // with method_resume. For deopt_resume2 we clear it now.
518 if (thread->popframe_forcing_deopt_reexecution())
519 thread->clear_popframe_condition();
520 #endif /* CC_INTERP */
521 }
522
523 // unpack_frames() is called at the end of the deoptimization handler
524 // and (in C2) at the end of the uncommon trap handler. Note this fact
525 // so that an asynchronous stack walker can work again. This counter is
526 // incremented at the beginning of fetch_unroll_info() and (in C2) at
527 // the beginning of uncommon_trap().
528 thread->dec_in_deopt_handler();
529 }
530
531
532 // Return BasicType of value being returned
533 JRT_LEAF(BasicType, Deoptimization::unpack_frames(JavaThread* thread, int exec_mode))
534
535 // We are already active int he special DeoptResourceMark any ResourceObj's we
536 // allocate will be freed at the end of the routine.
537
538 // It is actually ok to allocate handles in a leaf method. It causes no safepoints,
539 // but makes the entry a little slower. There is however a little dance we have to
540 // do in debug mode to get around the NoHandleMark code in the JRT_LEAF macro
541 ResetNoHandleMark rnhm; // No-op in release/product versions
542 HandleMark hm;
543
544 frame stub_frame = thread->last_frame();
545
546 // Since the frame to unpack is the top frame of this thread, the vframe_array_head
547 // must point to the vframeArray for the unpack frame.
548 vframeArray* array = thread->vframe_array_head();
549
550 #ifndef PRODUCT
551 if (TraceDeoptimization) {
552 ttyLocker ttyl;
553 tty->print_cr("DEOPT UNPACKING thread " INTPTR_FORMAT " vframeArray " INTPTR_FORMAT " mode %d", thread, array, exec_mode);
554 }
555 #endif
556 Events::log(thread, "DEOPT UNPACKING pc=" INTPTR_FORMAT " sp=" INTPTR_FORMAT " mode %d",
557 stub_frame.pc(), stub_frame.sp(), exec_mode);
558
559 UnrollBlock* info = array->unroll_block();
560
561 // Unpack the interpreter frames and any adapter frame (c2 only) we might create.
562 array->unpack_to_stack(stub_frame, exec_mode, info->caller_actual_parameters());
563
564 BasicType bt = info->return_type();
565
566 // If we have an exception pending, claim that the return type is an oop
567 // so the deopt_blob does not overwrite the exception_oop.
568
569 if (exec_mode == Unpack_exception)
570 bt = T_OBJECT;
571
572 // Cleanup thread deopt data
573 cleanup_deopt_info(thread, array);
574
575 #ifndef PRODUCT
576 if (VerifyStack) {
577 ResourceMark res_mark;
578
579 thread->validate_frame_layout();
580
581 // Verify that the just-unpacked frames match the interpreter's
582 // notions of expression stack and locals
583 vframeArray* cur_array = thread->vframe_array_last();
584 RegisterMap rm(thread, false);
585 rm.set_include_argument_oops(false);
586 bool is_top_frame = true;
587 int callee_size_of_parameters = 0;
588 int callee_max_locals = 0;
589 for (int i = 0; i < cur_array->frames(); i++) {
590 vframeArrayElement* el = cur_array->element(i);
591 frame* iframe = el->iframe();
592 guarantee(iframe->is_interpreted_frame(), "Wrong frame type");
593
594 // Get the oop map for this bci
595 InterpreterOopMap mask;
596 int cur_invoke_parameter_size = 0;
597 bool try_next_mask = false;
598 int next_mask_expression_stack_size = -1;
599 int top_frame_expression_stack_adjustment = 0;
600 methodHandle mh(thread, iframe->interpreter_frame_method());
601 OopMapCache::compute_one_oop_map(mh, iframe->interpreter_frame_bci(), &mask);
602 BytecodeStream str(mh);
603 str.set_start(iframe->interpreter_frame_bci());
604 int max_bci = mh->code_size();
605 // Get to the next bytecode if possible
606 assert(str.bci() < max_bci, "bci in interpreter frame out of bounds");
607 // Check to see if we can grab the number of outgoing arguments
608 // at an uncommon trap for an invoke (where the compiler
609 // generates debug info before the invoke has executed)
610 Bytecodes::Code cur_code = str.next();
611 if (cur_code == Bytecodes::_invokevirtual ||
612 cur_code == Bytecodes::_invokespecial ||
613 cur_code == Bytecodes::_invokestatic ||
614 cur_code == Bytecodes::_invokeinterface ||
615 cur_code == Bytecodes::_invokedynamic) {
616 Bytecode_invoke invoke(mh, iframe->interpreter_frame_bci());
617 Symbol* signature = invoke.signature();
618 ArgumentSizeComputer asc(signature);
619 cur_invoke_parameter_size = asc.size();
620 if (invoke.has_receiver()) {
621 // Add in receiver
622 ++cur_invoke_parameter_size;
623 }
624 if (i != 0 && !invoke.is_invokedynamic() && MethodHandles::has_member_arg(invoke.klass(), invoke.name())) {
625 callee_size_of_parameters++;
626 }
627 }
628 if (str.bci() < max_bci) {
629 Bytecodes::Code bc = str.next();
630 if (bc >= 0) {
631 // The interpreter oop map generator reports results before
632 // the current bytecode has executed except in the case of
633 // calls. It seems to be hard to tell whether the compiler
634 // has emitted debug information matching the "state before"
635 // a given bytecode or the state after, so we try both
636 switch (cur_code) {
637 case Bytecodes::_invokevirtual:
638 case Bytecodes::_invokespecial:
639 case Bytecodes::_invokestatic:
640 case Bytecodes::_invokeinterface:
641 case Bytecodes::_invokedynamic:
642 case Bytecodes::_athrow:
643 break;
644 default: {
645 InterpreterOopMap next_mask;
646 OopMapCache::compute_one_oop_map(mh, str.bci(), &next_mask);
647 next_mask_expression_stack_size = next_mask.expression_stack_size();
648 // Need to subtract off the size of the result type of
649 // the bytecode because this is not described in the
650 // debug info but returned to the interpreter in the TOS
651 // caching register
652 BasicType bytecode_result_type = Bytecodes::result_type(cur_code);
653 if (bytecode_result_type != T_ILLEGAL) {
654 top_frame_expression_stack_adjustment = type2size[bytecode_result_type];
655 }
656 assert(top_frame_expression_stack_adjustment >= 0, "");
657 try_next_mask = true;
658 break;
659 }
660 }
661 }
662 }
663
664 // Verify stack depth and oops in frame
665 // This assertion may be dependent on the platform we're running on and may need modification (tested on x86 and sparc)
666 if (!(
667 /* SPARC */
668 (iframe->interpreter_frame_expression_stack_size() == mask.expression_stack_size() + callee_size_of_parameters) ||
669 /* x86 */
670 (iframe->interpreter_frame_expression_stack_size() == mask.expression_stack_size() + callee_max_locals) ||
671 (try_next_mask &&
672 (iframe->interpreter_frame_expression_stack_size() == (next_mask_expression_stack_size -
673 top_frame_expression_stack_adjustment))) ||
674 (is_top_frame && (exec_mode == Unpack_exception) && iframe->interpreter_frame_expression_stack_size() == 0) ||
675 (is_top_frame && (exec_mode == Unpack_uncommon_trap || exec_mode == Unpack_reexecute || el->should_reexecute()) &&
676 (iframe->interpreter_frame_expression_stack_size() == mask.expression_stack_size() + cur_invoke_parameter_size))
677 )) {
678 ttyLocker ttyl;
679
680 // Print out some information that will help us debug the problem
681 tty->print_cr("Wrong number of expression stack elements during deoptimization");
682 tty->print_cr(" Error occurred while verifying frame %d (0..%d, 0 is topmost)", i, cur_array->frames() - 1);
683 tty->print_cr(" Fabricated interpreter frame had %d expression stack elements",
684 iframe->interpreter_frame_expression_stack_size());
685 tty->print_cr(" Interpreter oop map had %d expression stack elements", mask.expression_stack_size());
686 tty->print_cr(" try_next_mask = %d", try_next_mask);
687 tty->print_cr(" next_mask_expression_stack_size = %d", next_mask_expression_stack_size);
688 tty->print_cr(" callee_size_of_parameters = %d", callee_size_of_parameters);
689 tty->print_cr(" callee_max_locals = %d", callee_max_locals);
690 tty->print_cr(" top_frame_expression_stack_adjustment = %d", top_frame_expression_stack_adjustment);
691 tty->print_cr(" exec_mode = %d", exec_mode);
692 tty->print_cr(" cur_invoke_parameter_size = %d", cur_invoke_parameter_size);
693 tty->print_cr(" Thread = " INTPTR_FORMAT ", thread ID = " UINTX_FORMAT, thread, thread->osthread()->thread_id());
694 tty->print_cr(" Interpreted frames:");
695 for (int k = 0; k < cur_array->frames(); k++) {
696 vframeArrayElement* el = cur_array->element(k);
697 tty->print_cr(" %s (bci %d)", el->method()->name_and_sig_as_C_string(), el->bci());
698 }
699 cur_array->print_on_2(tty);
700 guarantee(false, "wrong number of expression stack elements during deopt");
701 }
702 VerifyOopClosure verify;
703 iframe->oops_interpreted_do(&verify, NULL, &rm, false);
704 callee_size_of_parameters = mh->size_of_parameters();
705 callee_max_locals = mh->max_locals();
706 is_top_frame = false;
707 }
708 }
709 #endif /* !PRODUCT */
710
711
712 return bt;
713 JRT_END
714
715
716 int Deoptimization::deoptimize_dependents() {
717 Threads::deoptimized_wrt_marked_nmethods();
718 return 0;
719 }
720
721 Deoptimization::DeoptAction Deoptimization::_unloaded_action
722 = Deoptimization::Action_reinterpret;
723
724 #ifdef COMPILER2
725 bool Deoptimization::realloc_objects(JavaThread* thread, frame* fr, GrowableArray<ScopeValue*>* objects, TRAPS) {
726 Handle pending_exception(thread->pending_exception());
727 const char* exception_file = thread->exception_file();
728 int exception_line = thread->exception_line();
729 thread->clear_pending_exception();
730
731 bool failures = false;
732
733 for (int i = 0; i < objects->length(); i++) {
734 assert(objects->at(i)->is_object(), "invalid debug information");
735 ObjectValue* sv = (ObjectValue*) objects->at(i);
736
737 KlassHandle k(java_lang_Class::as_Klass(sv->klass()->as_ConstantOopReadValue()->value()()));
738 oop obj = NULL;
739
740 if (k->oop_is_instance()) {
741 InstanceKlass* ik = InstanceKlass::cast(k());
742 obj = ik->allocate_instance(THREAD);
743 } else if (k->oop_is_typeArray()) {
744 TypeArrayKlass* ak = TypeArrayKlass::cast(k());
745 assert(sv->field_size() % type2size[ak->element_type()] == 0, "non-integral array length");
746 int len = sv->field_size() / type2size[ak->element_type()];
747 obj = ak->allocate(len, THREAD);
748 } else if (k->oop_is_objArray()) {
749 ObjArrayKlass* ak = ObjArrayKlass::cast(k());
750 obj = ak->allocate(sv->field_size(), THREAD);
751 }
752
753 if (obj == NULL) {
754 failures = true;
755 }
756
757 assert(sv->value().is_null(), "redundant reallocation");
758 assert(obj != NULL || HAS_PENDING_EXCEPTION, "allocation should succeed or we should get an exception");
759 CLEAR_PENDING_EXCEPTION;
760 sv->set_value(obj);
761 }
762
763 if (failures) {
764 THROW_OOP_(Universe::out_of_memory_error_realloc_objects(), failures);
765 } else if (pending_exception.not_null()) {
766 thread->set_pending_exception(pending_exception(), exception_file, exception_line);
767 }
768
769 return failures;
770 }
771
772 // This assumes that the fields are stored in ObjectValue in the same order
773 // they are yielded by do_nonstatic_fields.
774 class FieldReassigner: public FieldClosure {
775 frame* _fr;
776 RegisterMap* _reg_map;
777 ObjectValue* _sv;
778 InstanceKlass* _ik;
779 oop _obj;
780
781 int _i;
782 public:
783 FieldReassigner(frame* fr, RegisterMap* reg_map, ObjectValue* sv, oop obj) :
784 _fr(fr), _reg_map(reg_map), _sv(sv), _obj(obj), _i(0) {}
785
786 int i() const { return _i; }
787
788
789 void do_field(fieldDescriptor* fd) {
790 intptr_t val;
791 StackValue* value =
792 StackValue::create_stack_value(_fr, _reg_map, _sv->field_at(i()));
793 int offset = fd->offset();
794 switch (fd->field_type()) {
795 case T_OBJECT: case T_ARRAY:
796 assert(value->type() == T_OBJECT, "Agreement.");
797 _obj->obj_field_put(offset, value->get_obj()());
798 break;
799
800 case T_LONG: case T_DOUBLE: {
801 assert(value->type() == T_INT, "Agreement.");
802 StackValue* low =
803 StackValue::create_stack_value(_fr, _reg_map, _sv->field_at(++_i));
804 #ifdef _LP64
805 jlong res = (jlong)low->get_int();
806 #else
807 #ifdef SPARC
808 // For SPARC we have to swap high and low words.
809 jlong res = jlong_from((jint)low->get_int(), (jint)value->get_int());
810 #else
811 jlong res = jlong_from((jint)value->get_int(), (jint)low->get_int());
812 #endif //SPARC
813 #endif
814 _obj->long_field_put(offset, res);
815 break;
816 }
817 // Have to cast to INT (32 bits) pointer to avoid little/big-endian problem.
818 case T_INT: case T_FLOAT: // 4 bytes.
819 assert(value->type() == T_INT, "Agreement.");
820 val = value->get_int();
821 _obj->int_field_put(offset, (jint)*((jint*)&val));
822 break;
823
824 case T_SHORT: case T_CHAR: // 2 bytes
825 assert(value->type() == T_INT, "Agreement.");
826 val = value->get_int();
827 _obj->short_field_put(offset, (jshort)*((jint*)&val));
828 break;
829
830 case T_BOOLEAN: case T_BYTE: // 1 byte
831 assert(value->type() == T_INT, "Agreement.");
832 val = value->get_int();
833 _obj->bool_field_put(offset, (jboolean)*((jint*)&val));
834 break;
835
836 default:
837 ShouldNotReachHere();
838 }
839 _i++;
840 }
841 };
842
843 // restore elements of an eliminated type array
844 void Deoptimization::reassign_type_array_elements(frame* fr, RegisterMap* reg_map, ObjectValue* sv, typeArrayOop obj, BasicType type) {
845 int index = 0;
846 intptr_t val;
847
848 for (int i = 0; i < sv->field_size(); i++) {
849 StackValue* value = StackValue::create_stack_value(fr, reg_map, sv->field_at(i));
850 switch(type) {
851 case T_LONG: case T_DOUBLE: {
852 assert(value->type() == T_INT, "Agreement.");
853 StackValue* low =
854 StackValue::create_stack_value(fr, reg_map, sv->field_at(++i));
855 #ifdef _LP64
856 jlong res = (jlong)low->get_int();
857 #else
858 #ifdef SPARC
859 // For SPARC we have to swap high and low words.
860 jlong res = jlong_from((jint)low->get_int(), (jint)value->get_int());
861 #else
862 jlong res = jlong_from((jint)value->get_int(), (jint)low->get_int());
863 #endif //SPARC
864 #endif
865 obj->long_at_put(index, res);
866 break;
867 }
868
869 // Have to cast to INT (32 bits) pointer to avoid little/big-endian problem.
870 case T_INT: case T_FLOAT: // 4 bytes.
871 assert(value->type() == T_INT, "Agreement.");
872 val = value->get_int();
873 obj->int_at_put(index, (jint)*((jint*)&val));
874 break;
875
876 case T_SHORT: case T_CHAR: // 2 bytes
877 assert(value->type() == T_INT, "Agreement.");
878 val = value->get_int();
879 obj->short_at_put(index, (jshort)*((jint*)&val));
880 break;
881
882 case T_BOOLEAN: case T_BYTE: // 1 byte
883 assert(value->type() == T_INT, "Agreement.");
884 val = value->get_int();
885 obj->bool_at_put(index, (jboolean)*((jint*)&val));
886 break;
887
888 default:
889 ShouldNotReachHere();
890 }
891 index++;
892 }
893 }
894
895
896 // restore fields of an eliminated object array
897 void Deoptimization::reassign_object_array_elements(frame* fr, RegisterMap* reg_map, ObjectValue* sv, objArrayOop obj) {
898 for (int i = 0; i < sv->field_size(); i++) {
899 StackValue* value = StackValue::create_stack_value(fr, reg_map, sv->field_at(i));
900 assert(value->type() == T_OBJECT, "object element expected");
901 obj->obj_at_put(i, value->get_obj()());
902 }
903 }
904
905
906 // restore fields of all eliminated objects and arrays
907 void Deoptimization::reassign_fields(frame* fr, RegisterMap* reg_map, GrowableArray<ScopeValue*>* objects, bool realloc_failures) {
908 for (int i = 0; i < objects->length(); i++) {
909 ObjectValue* sv = (ObjectValue*) objects->at(i);
910 KlassHandle k(java_lang_Class::as_Klass(sv->klass()->as_ConstantOopReadValue()->value()()));
911 Handle obj = sv->value();
912 assert(obj.not_null() || realloc_failures, "reallocation was missed");
913 if (obj.is_null()) {
914 continue;
915 }
916
917 if (k->oop_is_instance()) {
918 InstanceKlass* ik = InstanceKlass::cast(k());
919 FieldReassigner reassign(fr, reg_map, sv, obj());
920 ik->do_nonstatic_fields(&reassign);
921 } else if (k->oop_is_typeArray()) {
922 TypeArrayKlass* ak = TypeArrayKlass::cast(k());
923 reassign_type_array_elements(fr, reg_map, sv, (typeArrayOop) obj(), ak->element_type());
924 } else if (k->oop_is_objArray()) {
925 reassign_object_array_elements(fr, reg_map, sv, (objArrayOop) obj());
926 }
927 }
928 }
929
930
931 // relock objects for which synchronization was eliminated
932 void Deoptimization::relock_objects(GrowableArray<MonitorInfo*>* monitors, JavaThread* thread, bool realloc_failures) {
933 for (int i = 0; i < monitors->length(); i++) {
934 MonitorInfo* mon_info = monitors->at(i);
935 if (mon_info->eliminated()) {
936 assert(!mon_info->owner_is_scalar_replaced() || realloc_failures, "reallocation was missed");
937 if (!mon_info->owner_is_scalar_replaced()) {
938 Handle obj = Handle(mon_info->owner());
939 markOop mark = obj->mark();
940 if (UseBiasedLocking && mark->has_bias_pattern()) {
941 // New allocated objects may have the mark set to anonymously biased.
942 // Also the deoptimized method may called methods with synchronization
943 // where the thread-local object is bias locked to the current thread.
944 assert(mark->is_biased_anonymously() ||
945 mark->biased_locker() == thread, "should be locked to current thread");
946 // Reset mark word to unbiased prototype.
947 markOop unbiased_prototype = markOopDesc::prototype()->set_age(mark->age());
948 obj->set_mark(unbiased_prototype);
949 }
950 BasicLock* lock = mon_info->lock();
951 ObjectSynchronizer::slow_enter(obj, lock, thread);
952 assert(mon_info->owner()->is_locked(), "object must be locked now");
953 }
954 }
955 }
956 }
957
958
959 #ifndef PRODUCT
960 // print information about reallocated objects
961 void Deoptimization::print_objects(GrowableArray<ScopeValue*>* objects, bool realloc_failures) {
962 fieldDescriptor fd;
963
964 for (int i = 0; i < objects->length(); i++) {
965 ObjectValue* sv = (ObjectValue*) objects->at(i);
966 KlassHandle k(java_lang_Class::as_Klass(sv->klass()->as_ConstantOopReadValue()->value()()));
967 Handle obj = sv->value();
968
969 tty->print(" object <" INTPTR_FORMAT "> of type ", (void *)sv->value()());
970 k->print_value();
971 assert(obj.not_null() || realloc_failures, "reallocation was missed");
972 if (obj.is_null()) {
973 tty->print(" allocation failed");
974 } else {
975 tty->print(" allocated (%d bytes)", obj->size() * HeapWordSize);
976 }
977 tty->cr();
978
979 if (Verbose && !obj.is_null()) {
980 k->oop_print_on(obj(), tty);
981 }
982 }
983 }
984 #endif
985 #endif // COMPILER2
986
987 vframeArray* Deoptimization::create_vframeArray(JavaThread* thread, frame fr, RegisterMap *reg_map, GrowableArray<compiledVFrame*>* chunk, bool realloc_failures) {
988 Events::log(thread, "DEOPT PACKING pc=" INTPTR_FORMAT " sp=" INTPTR_FORMAT, fr.pc(), fr.sp());
989
990 #ifndef PRODUCT
991 if (TraceDeoptimization) {
992 ttyLocker ttyl;
993 tty->print("DEOPT PACKING thread " INTPTR_FORMAT " ", thread);
994 fr.print_on(tty);
995 tty->print_cr(" Virtual frames (innermost first):");
996 for (int index = 0; index < chunk->length(); index++) {
997 compiledVFrame* vf = chunk->at(index);
998 tty->print(" %2d - ", index);
999 vf->print_value();
1000 int bci = chunk->at(index)->raw_bci();
1001 const char* code_name;
1002 if (bci == SynchronizationEntryBCI) {
1003 code_name = "sync entry";
1004 } else {
1005 Bytecodes::Code code = vf->method()->code_at(bci);
1006 code_name = Bytecodes::name(code);
1007 }
1008 tty->print(" - %s", code_name);
1009 tty->print_cr(" @ bci %d ", bci);
1010 if (Verbose) {
1011 vf->print();
1012 tty->cr();
1013 }
1014 }
1015 }
1016 #endif
1017
1018 // Register map for next frame (used for stack crawl). We capture
1019 // the state of the deopt'ing frame's caller. Thus if we need to
1020 // stuff a C2I adapter we can properly fill in the callee-save
1021 // register locations.
1022 frame caller = fr.sender(reg_map);
1023 int frame_size = caller.sp() - fr.sp();
1024
1025 frame sender = caller;
1026
1027 // Since the Java thread being deoptimized will eventually adjust it's own stack,
1028 // the vframeArray containing the unpacking information is allocated in the C heap.
1029 // For Compiler1, the caller of the deoptimized frame is saved for use by unpack_frames().
1030 vframeArray* array = vframeArray::allocate(thread, frame_size, chunk, reg_map, sender, caller, fr, realloc_failures);
1031
1032 // Compare the vframeArray to the collected vframes
1033 assert(array->structural_compare(thread, chunk), "just checking");
1034
1035 #ifndef PRODUCT
1036 if (TraceDeoptimization) {
1037 ttyLocker ttyl;
1038 tty->print_cr(" Created vframeArray " INTPTR_FORMAT, array);
1039 }
1040 #endif // PRODUCT
1041
1042 return array;
1043 }
1044
1045 #ifdef COMPILER2
1046 void Deoptimization::pop_frames_failed_reallocs(JavaThread* thread, vframeArray* array) {
1047 // Reallocation of some scalar replaced objects failed. Record
1048 // that we need to pop all the interpreter frames for the
1049 // deoptimized compiled frame.
1050 assert(thread->frames_to_pop_failed_realloc() == 0, "missed frames to pop?");
1051 thread->set_frames_to_pop_failed_realloc(array->frames());
1052 // Unlock all monitors here otherwise the interpreter will see a
1053 // mix of locked and unlocked monitors (because of failed
1054 // reallocations of synchronized objects) and be confused.
1055 for (int i = 0; i < array->frames(); i++) {
1056 MonitorChunk* monitors = array->element(i)->monitors();
1057 if (monitors != NULL) {
1058 for (int j = 0; j < monitors->number_of_monitors(); j++) {
1059 BasicObjectLock* src = monitors->at(j);
1060 if (src->obj() != NULL) {
1061 ObjectSynchronizer::fast_exit(src->obj(), src->lock(), thread);
1062 }
1063 }
1064 array->element(i)->free_monitors(thread);
1065 #ifdef ASSERT
1066 array->element(i)->set_removed_monitors();
1067 #endif
1068 }
1069 }
1070 }
1071 #endif
1072
1073 static void collect_monitors(compiledVFrame* cvf, GrowableArray<Handle>* objects_to_revoke) {
1074 GrowableArray<MonitorInfo*>* monitors = cvf->monitors();
1075 for (int i = 0; i < monitors->length(); i++) {
1076 MonitorInfo* mon_info = monitors->at(i);
1077 if (!mon_info->eliminated() && mon_info->owner() != NULL) {
1078 objects_to_revoke->append(Handle(mon_info->owner()));
1079 }
1080 }
1081 }
1082
1083
1084 void Deoptimization::revoke_biases_of_monitors(JavaThread* thread, frame fr, RegisterMap* map) {
1085 if (!UseBiasedLocking) {
1086 return;
1087 }
1088
1089 GrowableArray<Handle>* objects_to_revoke = new GrowableArray<Handle>();
1090
1091 // Unfortunately we don't have a RegisterMap available in most of
1092 // the places we want to call this routine so we need to walk the
1093 // stack again to update the register map.
1094 if (map == NULL || !map->update_map()) {
1095 StackFrameStream sfs(thread, true);
1096 bool found = false;
1097 while (!found && !sfs.is_done()) {
1098 frame* cur = sfs.current();
1099 sfs.next();
1100 found = cur->id() == fr.id();
1101 }
1102 assert(found, "frame to be deoptimized not found on target thread's stack");
1103 map = sfs.register_map();
1104 }
1105
1106 vframe* vf = vframe::new_vframe(&fr, map, thread);
1107 compiledVFrame* cvf = compiledVFrame::cast(vf);
1108 // Revoke monitors' biases in all scopes
1109 while (!cvf->is_top()) {
1110 collect_monitors(cvf, objects_to_revoke);
1111 cvf = compiledVFrame::cast(cvf->sender());
1112 }
1113 collect_monitors(cvf, objects_to_revoke);
1114
1115 if (SafepointSynchronize::is_at_safepoint()) {
1116 BiasedLocking::revoke_at_safepoint(objects_to_revoke);
1117 } else {
1118 BiasedLocking::revoke(objects_to_revoke);
1119 }
1120 }
1121
1122
1123 void Deoptimization::revoke_biases_of_monitors(CodeBlob* cb) {
1124 if (!UseBiasedLocking) {
1125 return;
1126 }
1127
1128 assert(SafepointSynchronize::is_at_safepoint(), "must only be called from safepoint");
1129 GrowableArray<Handle>* objects_to_revoke = new GrowableArray<Handle>();
1130 for (JavaThread* jt = Threads::first(); jt != NULL ; jt = jt->next()) {
1131 if (jt->has_last_Java_frame()) {
1132 StackFrameStream sfs(jt, true);
1133 while (!sfs.is_done()) {
1134 frame* cur = sfs.current();
1135 if (cb->contains(cur->pc())) {
1136 vframe* vf = vframe::new_vframe(cur, sfs.register_map(), jt);
1137 compiledVFrame* cvf = compiledVFrame::cast(vf);
1138 // Revoke monitors' biases in all scopes
1139 while (!cvf->is_top()) {
1140 collect_monitors(cvf, objects_to_revoke);
1141 cvf = compiledVFrame::cast(cvf->sender());
1142 }
1143 collect_monitors(cvf, objects_to_revoke);
1144 }
1145 sfs.next();
1146 }
1147 }
1148 }
1149 BiasedLocking::revoke_at_safepoint(objects_to_revoke);
1150 }
1151
1152
1153 void Deoptimization::deoptimize_single_frame(JavaThread* thread, frame fr) {
1154 assert(fr.can_be_deoptimized(), "checking frame type");
1155
1156 gather_statistics(Reason_constraint, Action_none, Bytecodes::_illegal);
1157
1158 // Patch the nmethod so that when execution returns to it we will
1159 // deopt the execution state and return to the interpreter.
1160 fr.deoptimize(thread);
1161 }
1162
1163 void Deoptimization::deoptimize(JavaThread* thread, frame fr, RegisterMap *map) {
1164 // Deoptimize only if the frame comes from compile code.
1165 // Do not deoptimize the frame which is already patched
1166 // during the execution of the loops below.
1167 if (!fr.is_compiled_frame() || fr.is_deoptimized_frame()) {
1168 return;
1169 }
1170 ResourceMark rm;
1171 DeoptimizationMarker dm;
1172 if (UseBiasedLocking) {
1173 revoke_biases_of_monitors(thread, fr, map);
1174 }
1175 deoptimize_single_frame(thread, fr);
1176
1177 }
1178
1179
1180 void Deoptimization::deoptimize_frame_internal(JavaThread* thread, intptr_t* id) {
1181 assert(thread == Thread::current() || SafepointSynchronize::is_at_safepoint(),
1182 "can only deoptimize other thread at a safepoint");
1183 // Compute frame and register map based on thread and sp.
1184 RegisterMap reg_map(thread, UseBiasedLocking);
1185 frame fr = thread->last_frame();
1186 while (fr.id() != id) {
1187 fr = fr.sender(®_map);
1188 }
1189 deoptimize(thread, fr, ®_map);
1190 }
1191
1192
1193 void Deoptimization::deoptimize_frame(JavaThread* thread, intptr_t* id) {
1194 if (thread == Thread::current()) {
1195 Deoptimization::deoptimize_frame_internal(thread, id);
1196 } else {
1197 VM_DeoptimizeFrame deopt(thread, id);
1198 VMThread::execute(&deopt);
1199 }
1200 }
1201
1202
1203 // JVMTI PopFrame support
1204 JRT_LEAF(void, Deoptimization::popframe_preserve_args(JavaThread* thread, int bytes_to_save, void* start_address))
1205 {
1206 thread->popframe_preserve_args(in_ByteSize(bytes_to_save), start_address);
1207 }
1208 JRT_END
1209
1210 MethodData*
1211 Deoptimization::get_method_data(JavaThread* thread, methodHandle m,
1212 bool create_if_missing) {
1213 Thread* THREAD = thread;
1214 MethodData* mdo = m()->method_data();
1215 if (mdo == NULL && create_if_missing && !HAS_PENDING_EXCEPTION) {
1216 // Build an MDO. Ignore errors like OutOfMemory;
1217 // that simply means we won't have an MDO to update.
1218 Method::build_interpreter_method_data(m, THREAD);
1219 if (HAS_PENDING_EXCEPTION) {
1220 assert((PENDING_EXCEPTION->is_a(SystemDictionary::OutOfMemoryError_klass())), "we expect only an OOM error here");
1221 CLEAR_PENDING_EXCEPTION;
1222 }
1223 mdo = m()->method_data();
1224 }
1225 return mdo;
1226 }
1227
1228 #if defined(COMPILER2) || defined(SHARK)
1229 void Deoptimization::load_class_by_index(constantPoolHandle constant_pool, int index, TRAPS) {
1230 // in case of an unresolved klass entry, load the class.
1231 if (constant_pool->tag_at(index).is_unresolved_klass()) {
1232 Klass* tk = constant_pool->klass_at_ignore_error(index, CHECK);
1233 return;
1234 }
1235
1236 if (!constant_pool->tag_at(index).is_symbol()) return;
1237
1238 Handle class_loader (THREAD, constant_pool->pool_holder()->class_loader());
1239 Symbol* symbol = constant_pool->symbol_at(index);
1240
1241 // class name?
1242 if (symbol->byte_at(0) != '(') {
1243 Handle protection_domain (THREAD, constant_pool->pool_holder()->protection_domain());
1244 SystemDictionary::resolve_or_null(symbol, class_loader, protection_domain, CHECK);
1245 return;
1246 }
1247
1248 // then it must be a signature!
1249 ResourceMark rm(THREAD);
1250 for (SignatureStream ss(symbol); !ss.is_done(); ss.next()) {
1251 if (ss.is_object()) {
1252 Symbol* class_name = ss.as_symbol(CHECK);
1253 Handle protection_domain (THREAD, constant_pool->pool_holder()->protection_domain());
1254 SystemDictionary::resolve_or_null(class_name, class_loader, protection_domain, CHECK);
1255 }
1256 }
1257 }
1258
1259
1260 void Deoptimization::load_class_by_index(constantPoolHandle constant_pool, int index) {
1261 EXCEPTION_MARK;
1262 load_class_by_index(constant_pool, index, THREAD);
1263 if (HAS_PENDING_EXCEPTION) {
1264 // Exception happened during classloading. We ignore the exception here, since it
1265 // is going to be rethrown since the current activation is going to be deoptimized and
1266 // the interpreter will re-execute the bytecode.
1267 CLEAR_PENDING_EXCEPTION;
1268 // Class loading called java code which may have caused a stack
1269 // overflow. If the exception was thrown right before the return
1270 // to the runtime the stack is no longer guarded. Reguard the
1271 // stack otherwise if we return to the uncommon trap blob and the
1272 // stack bang causes a stack overflow we crash.
1273 assert(THREAD->is_Java_thread(), "only a java thread can be here");
1274 JavaThread* thread = (JavaThread*)THREAD;
1275 bool guard_pages_enabled = thread->stack_yellow_zone_enabled();
1276 if (!guard_pages_enabled) guard_pages_enabled = thread->reguard_stack();
1277 assert(guard_pages_enabled, "stack banging in uncommon trap blob may cause crash");
1278 }
1279 }
1280
1281 JRT_ENTRY(void, Deoptimization::uncommon_trap_inner(JavaThread* thread, jint trap_request)) {
1282 HandleMark hm;
1283
1284 // uncommon_trap() is called at the beginning of the uncommon trap
1285 // handler. Note this fact before we start generating temporary frames
1286 // that can confuse an asynchronous stack walker. This counter is
1287 // decremented at the end of unpack_frames().
1288 thread->inc_in_deopt_handler();
1289
1290 // We need to update the map if we have biased locking.
1291 RegisterMap reg_map(thread, UseBiasedLocking);
1292 frame stub_frame = thread->last_frame();
1293 frame fr = stub_frame.sender(®_map);
1294 // Make sure the calling nmethod is not getting deoptimized and removed
1295 // before we are done with it.
1296 nmethodLocker nl(fr.pc());
1297
1298 // Log a message
1299 Events::log(thread, "Uncommon trap: trap_request=" PTR32_FORMAT " fr.pc=" INTPTR_FORMAT,
1300 trap_request, fr.pc());
1301
1302 {
1303 ResourceMark rm;
1304
1305 // Revoke biases of any monitors in the frame to ensure we can migrate them
1306 revoke_biases_of_monitors(thread, fr, ®_map);
1307
1308 DeoptReason reason = trap_request_reason(trap_request);
1309 DeoptAction action = trap_request_action(trap_request);
1310 jint unloaded_class_index = trap_request_index(trap_request); // CP idx or -1
1311
1312 vframe* vf = vframe::new_vframe(&fr, ®_map, thread);
1313 compiledVFrame* cvf = compiledVFrame::cast(vf);
1314
1315 nmethod* nm = cvf->code();
1316
1317 ScopeDesc* trap_scope = cvf->scope();
1318 methodHandle trap_method = trap_scope->method();
1319 int trap_bci = trap_scope->bci();
1320 Bytecodes::Code trap_bc = trap_method->java_code_at(trap_bci);
1321
1322 // Record this event in the histogram.
1323 gather_statistics(reason, action, trap_bc);
1324
1325 // Ensure that we can record deopt. history:
1326 // Need MDO to record RTM code generation state.
1327 bool create_if_missing = ProfileTraps || UseCodeAging RTM_OPT_ONLY( || UseRTMLocking );
1328
1329 MethodData* trap_mdo =
1330 get_method_data(thread, trap_method, create_if_missing);
1331
1332 // Log a message
1333 Events::log_deopt_message(thread, "Uncommon trap: reason=%s action=%s pc=" INTPTR_FORMAT " method=%s @ %d",
1334 trap_reason_name(reason), trap_action_name(action), fr.pc(),
1335 trap_method->name_and_sig_as_C_string(), trap_bci);
1336
1337 // Print a bunch of diagnostics, if requested.
1338 if (TraceDeoptimization || LogCompilation) {
1339 ResourceMark rm;
1340 ttyLocker ttyl;
1341 char buf[100];
1342 if (xtty != NULL) {
1343 xtty->begin_head("uncommon_trap thread='" UINTX_FORMAT"' %s",
1344 os::current_thread_id(),
1345 format_trap_request(buf, sizeof(buf), trap_request));
1346 nm->log_identity(xtty);
1347 }
1348 Symbol* class_name = NULL;
1349 bool unresolved = false;
1350 if (unloaded_class_index >= 0) {
1351 constantPoolHandle constants (THREAD, trap_method->constants());
1352 if (constants->tag_at(unloaded_class_index).is_unresolved_klass()) {
1353 class_name = constants->klass_name_at(unloaded_class_index);
1354 unresolved = true;
1355 if (xtty != NULL)
1356 xtty->print(" unresolved='1'");
1357 } else if (constants->tag_at(unloaded_class_index).is_symbol()) {
1358 class_name = constants->symbol_at(unloaded_class_index);
1359 }
1360 if (xtty != NULL)
1361 xtty->name(class_name);
1362 }
1363 if (xtty != NULL && trap_mdo != NULL && (int)reason < (int)MethodData::_trap_hist_limit) {
1364 // Dump the relevant MDO state.
1365 // This is the deopt count for the current reason, any previous
1366 // reasons or recompiles seen at this point.
1367 int dcnt = trap_mdo->trap_count(reason);
1368 if (dcnt != 0)
1369 xtty->print(" count='%d'", dcnt);
1370 ProfileData* pdata = trap_mdo->bci_to_data(trap_bci);
1371 int dos = (pdata == NULL)? 0: pdata->trap_state();
1372 if (dos != 0) {
1373 xtty->print(" state='%s'", format_trap_state(buf, sizeof(buf), dos));
1374 if (trap_state_is_recompiled(dos)) {
1375 int recnt2 = trap_mdo->overflow_recompile_count();
1376 if (recnt2 != 0)
1377 xtty->print(" recompiles2='%d'", recnt2);
1378 }
1379 }
1380 }
1381 if (xtty != NULL) {
1382 xtty->stamp();
1383 xtty->end_head();
1384 }
1385 if (TraceDeoptimization) { // make noise on the tty
1386 tty->print("Uncommon trap occurred in");
1387 nm->method()->print_short_name(tty);
1388 tty->print(" (@" INTPTR_FORMAT ") thread=" UINTX_FORMAT " reason=%s action=%s unloaded_class_index=%d",
1389 fr.pc(),
1390 os::current_thread_id(),
1391 trap_reason_name(reason),
1392 trap_action_name(action),
1393 unloaded_class_index);
1394 if (class_name != NULL) {
1395 tty->print(unresolved ? " unresolved class: " : " symbol: ");
1396 class_name->print_symbol_on(tty);
1397 }
1398 tty->cr();
1399 }
1400 if (xtty != NULL) {
1401 // Log the precise location of the trap.
1402 for (ScopeDesc* sd = trap_scope; ; sd = sd->sender()) {
1403 xtty->begin_elem("jvms bci='%d'", sd->bci());
1404 xtty->method(sd->method());
1405 xtty->end_elem();
1406 if (sd->is_top()) break;
1407 }
1408 xtty->tail("uncommon_trap");
1409 }
1410 }
1411 // (End diagnostic printout.)
1412
1413 // Load class if necessary
1414 if (unloaded_class_index >= 0) {
1415 constantPoolHandle constants(THREAD, trap_method->constants());
1416 load_class_by_index(constants, unloaded_class_index);
1417 }
1418
1419 // Flush the nmethod if necessary and desirable.
1420 //
1421 // We need to avoid situations where we are re-flushing the nmethod
1422 // because of a hot deoptimization site. Repeated flushes at the same
1423 // point need to be detected by the compiler and avoided. If the compiler
1424 // cannot avoid them (or has a bug and "refuses" to avoid them), this
1425 // module must take measures to avoid an infinite cycle of recompilation
1426 // and deoptimization. There are several such measures:
1427 //
1428 // 1. If a recompilation is ordered a second time at some site X
1429 // and for the same reason R, the action is adjusted to 'reinterpret',
1430 // to give the interpreter time to exercise the method more thoroughly.
1431 // If this happens, the method's overflow_recompile_count is incremented.
1432 //
1433 // 2. If the compiler fails to reduce the deoptimization rate, then
1434 // the method's overflow_recompile_count will begin to exceed the set
1435 // limit PerBytecodeRecompilationCutoff. If this happens, the action
1436 // is adjusted to 'make_not_compilable', and the method is abandoned
1437 // to the interpreter. This is a performance hit for hot methods,
1438 // but is better than a disastrous infinite cycle of recompilations.
1439 // (Actually, only the method containing the site X is abandoned.)
1440 //
1441 // 3. In parallel with the previous measures, if the total number of
1442 // recompilations of a method exceeds the much larger set limit
1443 // PerMethodRecompilationCutoff, the method is abandoned.
1444 // This should only happen if the method is very large and has
1445 // many "lukewarm" deoptimizations. The code which enforces this
1446 // limit is elsewhere (class nmethod, class Method).
1447 //
1448 // Note that the per-BCI 'is_recompiled' bit gives the compiler one chance
1449 // to recompile at each bytecode independently of the per-BCI cutoff.
1450 //
1451 // The decision to update code is up to the compiler, and is encoded
1452 // in the Action_xxx code. If the compiler requests Action_none
1453 // no trap state is changed, no compiled code is changed, and the
1454 // computation suffers along in the interpreter.
1455 //
1456 // The other action codes specify various tactics for decompilation
1457 // and recompilation. Action_maybe_recompile is the loosest, and
1458 // allows the compiled code to stay around until enough traps are seen,
1459 // and until the compiler gets around to recompiling the trapping method.
1460 //
1461 // The other actions cause immediate removal of the present code.
1462
1463 bool update_trap_state = (reason != Reason_tenured);
1464 bool make_not_entrant = false;
1465 bool make_not_compilable = false;
1466 bool reprofile = false;
1467 switch (action) {
1468 case Action_none:
1469 // Keep the old code.
1470 update_trap_state = false;
1471 break;
1472 case Action_maybe_recompile:
1473 // Do not need to invalidate the present code, but we can
1474 // initiate another
1475 // Start compiler without (necessarily) invalidating the nmethod.
1476 // The system will tolerate the old code, but new code should be
1477 // generated when possible.
1478 break;
1479 case Action_reinterpret:
1480 // Go back into the interpreter for a while, and then consider
1481 // recompiling form scratch.
1482 make_not_entrant = true;
1483 // Reset invocation counter for outer most method.
1484 // This will allow the interpreter to exercise the bytecodes
1485 // for a while before recompiling.
1486 // By contrast, Action_make_not_entrant is immediate.
1487 //
1488 // Note that the compiler will track null_check, null_assert,
1489 // range_check, and class_check events and log them as if they
1490 // had been traps taken from compiled code. This will update
1491 // the MDO trap history so that the next compilation will
1492 // properly detect hot trap sites.
1493 reprofile = true;
1494 break;
1495 case Action_make_not_entrant:
1496 // Request immediate recompilation, and get rid of the old code.
1497 // Make them not entrant, so next time they are called they get
1498 // recompiled. Unloaded classes are loaded now so recompile before next
1499 // time they are called. Same for uninitialized. The interpreter will
1500 // link the missing class, if any.
1501 make_not_entrant = true;
1502 break;
1503 case Action_make_not_compilable:
1504 // Give up on compiling this method at all.
1505 make_not_entrant = true;
1506 make_not_compilable = true;
1507 break;
1508 default:
1509 ShouldNotReachHere();
1510 }
1511
1512 // Setting +ProfileTraps fixes the following, on all platforms:
1513 // 4852688: ProfileInterpreter is off by default for ia64. The result is
1514 // infinite heroic-opt-uncommon-trap/deopt/recompile cycles, since the
1515 // recompile relies on a MethodData* to record heroic opt failures.
1516
1517 // Whether the interpreter is producing MDO data or not, we also need
1518 // to use the MDO to detect hot deoptimization points and control
1519 // aggressive optimization.
1520 bool inc_recompile_count = false;
1521 ProfileData* pdata = NULL;
1522 if (ProfileTraps && update_trap_state && trap_mdo != NULL) {
1523 assert(trap_mdo == get_method_data(thread, trap_method, false), "sanity");
1524 uint this_trap_count = 0;
1525 bool maybe_prior_trap = false;
1526 bool maybe_prior_recompile = false;
1527 pdata = query_update_method_data(trap_mdo, trap_bci, reason,
1528 nm->method(),
1529 //outputs:
1530 this_trap_count,
1531 maybe_prior_trap,
1532 maybe_prior_recompile);
1533 // Because the interpreter also counts null, div0, range, and class
1534 // checks, these traps from compiled code are double-counted.
1535 // This is harmless; it just means that the PerXTrapLimit values
1536 // are in effect a little smaller than they look.
1537
1538 DeoptReason per_bc_reason = reason_recorded_per_bytecode_if_any(reason);
1539 if (per_bc_reason != Reason_none) {
1540 // Now take action based on the partially known per-BCI history.
1541 if (maybe_prior_trap
1542 && this_trap_count >= (uint)PerBytecodeTrapLimit) {
1543 // If there are too many traps at this BCI, force a recompile.
1544 // This will allow the compiler to see the limit overflow, and
1545 // take corrective action, if possible. The compiler generally
1546 // does not use the exact PerBytecodeTrapLimit value, but instead
1547 // changes its tactics if it sees any traps at all. This provides
1548 // a little hysteresis, delaying a recompile until a trap happens
1549 // several times.
1550 //
1551 // Actually, since there is only one bit of counter per BCI,
1552 // the possible per-BCI counts are {0,1,(per-method count)}.
1553 // This produces accurate results if in fact there is only
1554 // one hot trap site, but begins to get fuzzy if there are
1555 // many sites. For example, if there are ten sites each
1556 // trapping two or more times, they each get the blame for
1557 // all of their traps.
1558 make_not_entrant = true;
1559 }
1560
1561 // Detect repeated recompilation at the same BCI, and enforce a limit.
1562 if (make_not_entrant && maybe_prior_recompile) {
1563 // More than one recompile at this point.
1564 inc_recompile_count = maybe_prior_trap;
1565 }
1566 } else {
1567 // For reasons which are not recorded per-bytecode, we simply
1568 // force recompiles unconditionally.
1569 // (Note that PerMethodRecompilationCutoff is enforced elsewhere.)
1570 make_not_entrant = true;
1571 }
1572
1573 // Go back to the compiler if there are too many traps in this method.
1574 if (this_trap_count >= per_method_trap_limit(reason)) {
1575 // If there are too many traps in this method, force a recompile.
1576 // This will allow the compiler to see the limit overflow, and
1577 // take corrective action, if possible.
1578 // (This condition is an unlikely backstop only, because the
1579 // PerBytecodeTrapLimit is more likely to take effect first,
1580 // if it is applicable.)
1581 make_not_entrant = true;
1582 }
1583
1584 // Here's more hysteresis: If there has been a recompile at
1585 // this trap point already, run the method in the interpreter
1586 // for a while to exercise it more thoroughly.
1587 if (make_not_entrant && maybe_prior_recompile && maybe_prior_trap) {
1588 reprofile = true;
1589 }
1590 }
1591
1592 // Take requested actions on the method:
1593
1594 // Recompile
1595 if (make_not_entrant) {
1596 if (!nm->make_not_entrant()) {
1597 return; // the call did not change nmethod's state
1598 }
1599
1600 if (pdata != NULL) {
1601 // Record the recompilation event, if any.
1602 int tstate0 = pdata->trap_state();
1603 int tstate1 = trap_state_set_recompiled(tstate0, true);
1604 if (tstate1 != tstate0)
1605 pdata->set_trap_state(tstate1);
1606 }
1607
1608 #if INCLUDE_RTM_OPT
1609 // Restart collecting RTM locking abort statistic if the method
1610 // is recompiled for a reason other than RTM state change.
1611 // Assume that in new recompiled code the statistic could be different,
1612 // for example, due to different inlining.
1613 if ((reason != Reason_rtm_state_change) && (trap_mdo != NULL) &&
1614 UseRTMDeopt && (nm->rtm_state() != ProfileRTM)) {
1615 trap_mdo->atomic_set_rtm_state(ProfileRTM);
1616 }
1617 #endif
1618 // For code aging we count traps separately here, using make_not_entrant()
1619 // as a guard against simultaneous deopts in multiple threads.
1620 if (reason == Reason_tenured && trap_mdo != NULL) {
1621 trap_mdo->inc_tenure_traps();
1622 }
1623 }
1624
1625 if (inc_recompile_count) {
1626 trap_mdo->inc_overflow_recompile_count();
1627 if ((uint)trap_mdo->overflow_recompile_count() >
1628 (uint)PerBytecodeRecompilationCutoff) {
1629 // Give up on the method containing the bad BCI.
1630 if (trap_method() == nm->method()) {
1631 make_not_compilable = true;
1632 } else {
1633 trap_method->set_not_compilable(CompLevel_full_optimization, true, "overflow_recompile_count > PerBytecodeRecompilationCutoff");
1634 // But give grace to the enclosing nm->method().
1635 }
1636 }
1637 }
1638
1639 // Reprofile
1640 if (reprofile) {
1641 CompilationPolicy::policy()->reprofile(trap_scope, nm->is_osr_method());
1642 }
1643
1644 // Give up compiling
1645 if (make_not_compilable && !nm->method()->is_not_compilable(CompLevel_full_optimization)) {
1646 assert(make_not_entrant, "consistent");
1647 nm->method()->set_not_compilable(CompLevel_full_optimization);
1648 }
1649
1650 } // Free marked resources
1651
1652 }
1653 JRT_END
1654
1655 ProfileData*
1656 Deoptimization::query_update_method_data(MethodData* trap_mdo,
1657 int trap_bci,
1658 Deoptimization::DeoptReason reason,
1659 Method* compiled_method,
1660 //outputs:
1661 uint& ret_this_trap_count,
1662 bool& ret_maybe_prior_trap,
1663 bool& ret_maybe_prior_recompile) {
1664 uint prior_trap_count = trap_mdo->trap_count(reason);
1665 uint this_trap_count = trap_mdo->inc_trap_count(reason);
1666
1667 // If the runtime cannot find a place to store trap history,
1668 // it is estimated based on the general condition of the method.
1669 // If the method has ever been recompiled, or has ever incurred
1670 // a trap with the present reason , then this BCI is assumed
1671 // (pessimistically) to be the culprit.
1672 bool maybe_prior_trap = (prior_trap_count != 0);
1673 bool maybe_prior_recompile = (trap_mdo->decompile_count() != 0);
1674 ProfileData* pdata = NULL;
1675
1676
1677 // For reasons which are recorded per bytecode, we check per-BCI data.
1678 DeoptReason per_bc_reason = reason_recorded_per_bytecode_if_any(reason);
1679 if (per_bc_reason != Reason_none) {
1680 // Find the profile data for this BCI. If there isn't one,
1681 // try to allocate one from the MDO's set of spares.
1682 // This will let us detect a repeated trap at this point.
1683 pdata = trap_mdo->allocate_bci_to_data(trap_bci, reason_is_speculate(reason) ? compiled_method : NULL);
1684
1685 if (pdata != NULL) {
1686 if (reason_is_speculate(reason) && !pdata->is_SpeculativeTrapData()) {
1687 if (LogCompilation && xtty != NULL) {
1688 ttyLocker ttyl;
1689 // no more room for speculative traps in this MDO
1690 xtty->elem("speculative_traps_oom");
1691 }
1692 }
1693 // Query the trap state of this profile datum.
1694 int tstate0 = pdata->trap_state();
1695 if (!trap_state_has_reason(tstate0, per_bc_reason))
1696 maybe_prior_trap = false;
1697 if (!trap_state_is_recompiled(tstate0))
1698 maybe_prior_recompile = false;
1699
1700 // Update the trap state of this profile datum.
1701 int tstate1 = tstate0;
1702 // Record the reason.
1703 tstate1 = trap_state_add_reason(tstate1, per_bc_reason);
1704 // Store the updated state on the MDO, for next time.
1705 if (tstate1 != tstate0)
1706 pdata->set_trap_state(tstate1);
1707 } else {
1708 if (LogCompilation && xtty != NULL) {
1709 ttyLocker ttyl;
1710 // Missing MDP? Leave a small complaint in the log.
1711 xtty->elem("missing_mdp bci='%d'", trap_bci);
1712 }
1713 }
1714 }
1715
1716 // Return results:
1717 ret_this_trap_count = this_trap_count;
1718 ret_maybe_prior_trap = maybe_prior_trap;
1719 ret_maybe_prior_recompile = maybe_prior_recompile;
1720 return pdata;
1721 }
1722
1723 void
1724 Deoptimization::update_method_data_from_interpreter(MethodData* trap_mdo, int trap_bci, int reason) {
1725 ResourceMark rm;
1726 // Ignored outputs:
1727 uint ignore_this_trap_count;
1728 bool ignore_maybe_prior_trap;
1729 bool ignore_maybe_prior_recompile;
1730 assert(!reason_is_speculate(reason), "reason speculate only used by compiler");
1731 query_update_method_data(trap_mdo, trap_bci,
1732 (DeoptReason)reason,
1733 NULL,
1734 ignore_this_trap_count,
1735 ignore_maybe_prior_trap,
1736 ignore_maybe_prior_recompile);
1737 }
1738
1739 Deoptimization::UnrollBlock* Deoptimization::uncommon_trap(JavaThread* thread, jint trap_request) {
1740
1741 // Still in Java no safepoints
1742 {
1743 // This enters VM and may safepoint
1744 uncommon_trap_inner(thread, trap_request);
1745 }
1746 return fetch_unroll_info_helper(thread);
1747 }
1748
1749 // Local derived constants.
1750 // Further breakdown of DataLayout::trap_state, as promised by DataLayout.
1751 const int DS_REASON_MASK = DataLayout::trap_mask >> 1;
1752 const int DS_RECOMPILE_BIT = DataLayout::trap_mask - DS_REASON_MASK;
1753
1754 //---------------------------trap_state_reason---------------------------------
1755 Deoptimization::DeoptReason
1756 Deoptimization::trap_state_reason(int trap_state) {
1757 // This assert provides the link between the width of DataLayout::trap_bits
1758 // and the encoding of "recorded" reasons. It ensures there are enough
1759 // bits to store all needed reasons in the per-BCI MDO profile.
1760 assert(DS_REASON_MASK >= Reason_RECORDED_LIMIT, "enough bits");
1761 int recompile_bit = (trap_state & DS_RECOMPILE_BIT);
1762 trap_state -= recompile_bit;
1763 if (trap_state == DS_REASON_MASK) {
1764 return Reason_many;
1765 } else {
1766 assert((int)Reason_none == 0, "state=0 => Reason_none");
1767 return (DeoptReason)trap_state;
1768 }
1769 }
1770 //-------------------------trap_state_has_reason-------------------------------
1771 int Deoptimization::trap_state_has_reason(int trap_state, int reason) {
1772 assert(reason_is_recorded_per_bytecode((DeoptReason)reason), "valid reason");
1773 assert(DS_REASON_MASK >= Reason_RECORDED_LIMIT, "enough bits");
1774 int recompile_bit = (trap_state & DS_RECOMPILE_BIT);
1775 trap_state -= recompile_bit;
1776 if (trap_state == DS_REASON_MASK) {
1777 return -1; // true, unspecifically (bottom of state lattice)
1778 } else if (trap_state == reason) {
1779 return 1; // true, definitely
1780 } else if (trap_state == 0) {
1781 return 0; // false, definitely (top of state lattice)
1782 } else {
1783 return 0; // false, definitely
1784 }
1785 }
1786 //-------------------------trap_state_add_reason-------------------------------
1787 int Deoptimization::trap_state_add_reason(int trap_state, int reason) {
1788 assert(reason_is_recorded_per_bytecode((DeoptReason)reason) || reason == Reason_many, "valid reason");
1789 int recompile_bit = (trap_state & DS_RECOMPILE_BIT);
1790 trap_state -= recompile_bit;
1791 if (trap_state == DS_REASON_MASK) {
1792 return trap_state + recompile_bit; // already at state lattice bottom
1793 } else if (trap_state == reason) {
1794 return trap_state + recompile_bit; // the condition is already true
1795 } else if (trap_state == 0) {
1796 return reason + recompile_bit; // no condition has yet been true
1797 } else {
1798 return DS_REASON_MASK + recompile_bit; // fall to state lattice bottom
1799 }
1800 }
1801 //-----------------------trap_state_is_recompiled------------------------------
1802 bool Deoptimization::trap_state_is_recompiled(int trap_state) {
1803 return (trap_state & DS_RECOMPILE_BIT) != 0;
1804 }
1805 //-----------------------trap_state_set_recompiled-----------------------------
1806 int Deoptimization::trap_state_set_recompiled(int trap_state, bool z) {
1807 if (z) return trap_state | DS_RECOMPILE_BIT;
1808 else return trap_state & ~DS_RECOMPILE_BIT;
1809 }
1810 //---------------------------format_trap_state---------------------------------
1811 // This is used for debugging and diagnostics, including LogFile output.
1812 const char* Deoptimization::format_trap_state(char* buf, size_t buflen,
1813 int trap_state) {
1814 DeoptReason reason = trap_state_reason(trap_state);
1815 bool recomp_flag = trap_state_is_recompiled(trap_state);
1816 // Re-encode the state from its decoded components.
1817 int decoded_state = 0;
1818 if (reason_is_recorded_per_bytecode(reason) || reason == Reason_many)
1819 decoded_state = trap_state_add_reason(decoded_state, reason);
1820 if (recomp_flag)
1821 decoded_state = trap_state_set_recompiled(decoded_state, recomp_flag);
1822 // If the state re-encodes properly, format it symbolically.
1823 // Because this routine is used for debugging and diagnostics,
1824 // be robust even if the state is a strange value.
1825 size_t len;
1826 if (decoded_state != trap_state) {
1827 // Random buggy state that doesn't decode??
1828 len = jio_snprintf(buf, buflen, "#%d", trap_state);
1829 } else {
1830 len = jio_snprintf(buf, buflen, "%s%s",
1831 trap_reason_name(reason),
1832 recomp_flag ? " recompiled" : "");
1833 }
1834 if (len >= buflen)
1835 buf[buflen-1] = '\0';
1836 return buf;
1837 }
1838
1839
1840 //--------------------------------statics--------------------------------------
1841 const char* Deoptimization::_trap_reason_name[] = {
1842 // Note: Keep this in sync. with enum DeoptReason.
1843 "none",
1844 "null_check",
1845 "null_assert",
1846 "range_check",
1847 "class_check",
1848 "array_check",
1849 "intrinsic",
1850 "bimorphic",
1851 "unloaded",
1852 "uninitialized",
1853 "unreached",
1854 "unhandled",
1855 "constraint",
1856 "div0_check",
1857 "age",
1858 "predicate",
1859 "loop_limit_check",
1860 "speculate_class_check",
1861 "speculate_null_check",
1862 "rtm_state_change",
1863 "unstable_if",
1864 "tenured"
1865 };
1866 const char* Deoptimization::_trap_action_name[] = {
1867 // Note: Keep this in sync. with enum DeoptAction.
1868 "none",
1869 "maybe_recompile",
1870 "reinterpret",
1871 "make_not_entrant",
1872 "make_not_compilable"
1873 };
1874
1875 const char* Deoptimization::trap_reason_name(int reason) {
1876 // Check that every reason has a name
1877 STATIC_ASSERT(sizeof(_trap_reason_name)/sizeof(const char*) == Reason_LIMIT);
1878
1879 if (reason == Reason_many) return "many";
1880 if ((uint)reason < Reason_LIMIT)
1881 return _trap_reason_name[reason];
1882 static char buf[20];
1883 sprintf(buf, "reason%d", reason);
1884 return buf;
1885 }
1886 const char* Deoptimization::trap_action_name(int action) {
1887 // Check that every action has a name
1888 STATIC_ASSERT(sizeof(_trap_action_name)/sizeof(const char*) == Action_LIMIT);
1889
1890 if ((uint)action < Action_LIMIT)
1891 return _trap_action_name[action];
1892 static char buf[20];
1893 sprintf(buf, "action%d", action);
1894 return buf;
1895 }
1896
1897 // This is used for debugging and diagnostics, including LogFile output.
1898 const char* Deoptimization::format_trap_request(char* buf, size_t buflen,
1899 int trap_request) {
1900 jint unloaded_class_index = trap_request_index(trap_request);
1901 const char* reason = trap_reason_name(trap_request_reason(trap_request));
1902 const char* action = trap_action_name(trap_request_action(trap_request));
1903 size_t len;
1904 if (unloaded_class_index < 0) {
1905 len = jio_snprintf(buf, buflen, "reason='%s' action='%s'",
1906 reason, action);
1907 } else {
1908 len = jio_snprintf(buf, buflen, "reason='%s' action='%s' index='%d'",
1909 reason, action, unloaded_class_index);
1910 }
1911 if (len >= buflen)
1912 buf[buflen-1] = '\0';
1913 return buf;
1914 }
1915
1916 juint Deoptimization::_deoptimization_hist
1917 [Deoptimization::Reason_LIMIT]
1918 [1 + Deoptimization::Action_LIMIT]
1919 [Deoptimization::BC_CASE_LIMIT]
1920 = {0};
1921
1922 enum {
1923 LSB_BITS = 8,
1924 LSB_MASK = right_n_bits(LSB_BITS)
1925 };
1926
1927 void Deoptimization::gather_statistics(DeoptReason reason, DeoptAction action,
1928 Bytecodes::Code bc) {
1929 assert(reason >= 0 && reason < Reason_LIMIT, "oob");
1930 assert(action >= 0 && action < Action_LIMIT, "oob");
1931 _deoptimization_hist[Reason_none][0][0] += 1; // total
1932 _deoptimization_hist[reason][0][0] += 1; // per-reason total
1933 juint* cases = _deoptimization_hist[reason][1+action];
1934 juint* bc_counter_addr = NULL;
1935 juint bc_counter = 0;
1936 // Look for an unused counter, or an exact match to this BC.
1937 if (bc != Bytecodes::_illegal) {
1938 for (int bc_case = 0; bc_case < BC_CASE_LIMIT; bc_case++) {
1939 juint* counter_addr = &cases[bc_case];
1940 juint counter = *counter_addr;
1941 if ((counter == 0 && bc_counter_addr == NULL)
1942 || (Bytecodes::Code)(counter & LSB_MASK) == bc) {
1943 // this counter is either free or is already devoted to this BC
1944 bc_counter_addr = counter_addr;
1945 bc_counter = counter | bc;
1946 }
1947 }
1948 }
1949 if (bc_counter_addr == NULL) {
1950 // Overflow, or no given bytecode.
1951 bc_counter_addr = &cases[BC_CASE_LIMIT-1];
1952 bc_counter = (*bc_counter_addr & ~LSB_MASK); // clear LSB
1953 }
1954 *bc_counter_addr = bc_counter + (1 << LSB_BITS);
1955 }
1956
1957 jint Deoptimization::total_deoptimization_count() {
1958 return _deoptimization_hist[Reason_none][0][0];
1959 }
1960
1961 jint Deoptimization::deoptimization_count(DeoptReason reason) {
1962 assert(reason >= 0 && reason < Reason_LIMIT, "oob");
1963 return _deoptimization_hist[reason][0][0];
1964 }
1965
1966 void Deoptimization::print_statistics() {
1967 juint total = total_deoptimization_count();
1968 juint account = total;
1969 if (total != 0) {
1970 ttyLocker ttyl;
1971 if (xtty != NULL) xtty->head("statistics type='deoptimization'");
1972 tty->print_cr("Deoptimization traps recorded:");
1973 #define PRINT_STAT_LINE(name, r) \
1974 tty->print_cr(" %4d (%4.1f%%) %s", (int)(r), ((r) * 100.0) / total, name);
1975 PRINT_STAT_LINE("total", total);
1976 // For each non-zero entry in the histogram, print the reason,
1977 // the action, and (if specifically known) the type of bytecode.
1978 for (int reason = 0; reason < Reason_LIMIT; reason++) {
1979 for (int action = 0; action < Action_LIMIT; action++) {
1980 juint* cases = _deoptimization_hist[reason][1+action];
1981 for (int bc_case = 0; bc_case < BC_CASE_LIMIT; bc_case++) {
1982 juint counter = cases[bc_case];
1983 if (counter != 0) {
1984 char name[1*K];
1985 Bytecodes::Code bc = (Bytecodes::Code)(counter & LSB_MASK);
1986 if (bc_case == BC_CASE_LIMIT && (int)bc == 0)
1987 bc = Bytecodes::_illegal;
1988 sprintf(name, "%s/%s/%s",
1989 trap_reason_name(reason),
1990 trap_action_name(action),
1991 Bytecodes::is_defined(bc)? Bytecodes::name(bc): "other");
1992 juint r = counter >> LSB_BITS;
1993 tty->print_cr(" %40s: " UINT32_FORMAT " (%.1f%%)", name, r, (r * 100.0) / total);
1994 account -= r;
1995 }
1996 }
1997 }
1998 }
1999 if (account != 0) {
2000 PRINT_STAT_LINE("unaccounted", account);
2001 }
2002 #undef PRINT_STAT_LINE
2003 if (xtty != NULL) xtty->tail("statistics");
2004 }
2005 }
2006 #else // COMPILER2 || SHARK
2007
2008
2009 // Stubs for C1 only system.
2010 bool Deoptimization::trap_state_is_recompiled(int trap_state) {
2011 return false;
2012 }
2013
2014 const char* Deoptimization::trap_reason_name(int reason) {
2015 return "unknown";
2016 }
2017
2018 void Deoptimization::print_statistics() {
2019 // no output
2020 }
2021
2022 void
2023 Deoptimization::update_method_data_from_interpreter(MethodData* trap_mdo, int trap_bci, int reason) {
2024 // no udpate
2025 }
2026
2027 int Deoptimization::trap_state_has_reason(int trap_state, int reason) {
2028 return 0;
2029 }
2030
2031 void Deoptimization::gather_statistics(DeoptReason reason, DeoptAction action,
2032 Bytecodes::Code bc) {
2033 // no update
2034 }
2035
2036 const char* Deoptimization::format_trap_state(char* buf, size_t buflen,
2037 int trap_state) {
2038 jio_snprintf(buf, buflen, "#%d", trap_state);
2039 return buf;
2040 }
2041
2042 #endif // COMPILER2 || SHARK