Tue, 11 Mar 2008 11:25:13 -0700
6667620: (Escape Analysis) fix deoptimization for scalar replaced objects
Summary: Deoptimization code for reallocation and relocking scalar replaced objects has to be fixed.
Reviewed-by: rasbold, never
1 /*
2 * Copyright 1997-2007 Sun Microsystems, Inc. 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 Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
20 * CA 95054 USA or visit www.sun.com if you need additional information or
21 * have any questions.
22 *
23 */
25 #include "incls/_precompiled.incl"
26 #include "incls/_deoptimization.cpp.incl"
28 bool DeoptimizationMarker::_is_active = false;
30 Deoptimization::UnrollBlock::UnrollBlock(int size_of_deoptimized_frame,
31 int caller_adjustment,
32 int number_of_frames,
33 intptr_t* frame_sizes,
34 address* frame_pcs,
35 BasicType return_type) {
36 _size_of_deoptimized_frame = size_of_deoptimized_frame;
37 _caller_adjustment = caller_adjustment;
38 _number_of_frames = number_of_frames;
39 _frame_sizes = frame_sizes;
40 _frame_pcs = frame_pcs;
41 _register_block = NEW_C_HEAP_ARRAY(intptr_t, RegisterMap::reg_count * 2);
42 _return_type = return_type;
43 // PD (x86 only)
44 _counter_temp = 0;
45 _initial_fp = 0;
46 _unpack_kind = 0;
47 _sender_sp_temp = 0;
49 _total_frame_sizes = size_of_frames();
50 }
53 Deoptimization::UnrollBlock::~UnrollBlock() {
54 FREE_C_HEAP_ARRAY(intptr_t, _frame_sizes);
55 FREE_C_HEAP_ARRAY(intptr_t, _frame_pcs);
56 FREE_C_HEAP_ARRAY(intptr_t, _register_block);
57 }
60 intptr_t* Deoptimization::UnrollBlock::value_addr_at(int register_number) const {
61 assert(register_number < RegisterMap::reg_count, "checking register number");
62 return &_register_block[register_number * 2];
63 }
67 int Deoptimization::UnrollBlock::size_of_frames() const {
68 // Acount first for the adjustment of the initial frame
69 int result = _caller_adjustment;
70 for (int index = 0; index < number_of_frames(); index++) {
71 result += frame_sizes()[index];
72 }
73 return result;
74 }
77 void Deoptimization::UnrollBlock::print() {
78 ttyLocker ttyl;
79 tty->print_cr("UnrollBlock");
80 tty->print_cr(" size_of_deoptimized_frame = %d", _size_of_deoptimized_frame);
81 tty->print( " frame_sizes: ");
82 for (int index = 0; index < number_of_frames(); index++) {
83 tty->print("%d ", frame_sizes()[index]);
84 }
85 tty->cr();
86 }
89 // In order to make fetch_unroll_info work properly with escape
90 // analysis, The method was changed from JRT_LEAF to JRT_BLOCK_ENTRY and
91 // ResetNoHandleMark and HandleMark were removed from it. The actual reallocation
92 // of previously eliminated objects occurs in realloc_objects, which is
93 // called from the method fetch_unroll_info_helper below.
94 JRT_BLOCK_ENTRY(Deoptimization::UnrollBlock*, Deoptimization::fetch_unroll_info(JavaThread* thread))
95 // It is actually ok to allocate handles in a leaf method. It causes no safepoints,
96 // but makes the entry a little slower. There is however a little dance we have to
97 // do in debug mode to get around the NoHandleMark code in the JRT_LEAF macro
99 // fetch_unroll_info() is called at the beginning of the deoptimization
100 // handler. Note this fact before we start generating temporary frames
101 // that can confuse an asynchronous stack walker. This counter is
102 // decremented at the end of unpack_frames().
103 thread->inc_in_deopt_handler();
105 return fetch_unroll_info_helper(thread);
106 JRT_END
109 // This is factored, since it is both called from a JRT_LEAF (deoptimization) and a JRT_ENTRY (uncommon_trap)
110 Deoptimization::UnrollBlock* Deoptimization::fetch_unroll_info_helper(JavaThread* thread) {
112 // Note: there is a safepoint safety issue here. No matter whether we enter
113 // via vanilla deopt or uncommon trap we MUST NOT stop at a safepoint once
114 // the vframeArray is created.
115 //
117 // Allocate our special deoptimization ResourceMark
118 DeoptResourceMark* dmark = new DeoptResourceMark(thread);
119 assert(thread->deopt_mark() == NULL, "Pending deopt!");
120 thread->set_deopt_mark(dmark);
122 frame stub_frame = thread->last_frame(); // Makes stack walkable as side effect
123 RegisterMap map(thread, true);
124 RegisterMap dummy_map(thread, false);
125 // Now get the deoptee with a valid map
126 frame deoptee = stub_frame.sender(&map);
128 // Create a growable array of VFrames where each VFrame represents an inlined
129 // Java frame. This storage is allocated with the usual system arena.
130 assert(deoptee.is_compiled_frame(), "Wrong frame type");
131 GrowableArray<compiledVFrame*>* chunk = new GrowableArray<compiledVFrame*>(10);
132 vframe* vf = vframe::new_vframe(&deoptee, &map, thread);
133 while (!vf->is_top()) {
134 assert(vf->is_compiled_frame(), "Wrong frame type");
135 chunk->push(compiledVFrame::cast(vf));
136 vf = vf->sender();
137 }
138 assert(vf->is_compiled_frame(), "Wrong frame type");
139 chunk->push(compiledVFrame::cast(vf));
141 #ifdef COMPILER2
142 // Reallocate the non-escaping objects and restore their fields. Then
143 // relock objects if synchronization on them was eliminated.
144 if (DoEscapeAnalysis) {
145 if (EliminateAllocations) {
146 GrowableArray<ScopeValue*>* objects = chunk->at(0)->scope()->objects();
147 bool reallocated = false;
148 if (objects != NULL) {
149 JRT_BLOCK
150 reallocated = realloc_objects(thread, &deoptee, objects, THREAD);
151 JRT_END
152 }
153 if (reallocated) {
154 reassign_fields(&deoptee, &map, objects);
155 #ifndef PRODUCT
156 if (TraceDeoptimization) {
157 ttyLocker ttyl;
158 tty->print_cr("REALLOC OBJECTS in thread " INTPTR_FORMAT, thread);
159 print_objects(objects);
160 }
161 #endif
162 }
163 }
164 if (EliminateLocks) {
165 for (int i = 0; i < chunk->length(); i++) {
166 GrowableArray<MonitorValue*>* monitors = chunk->at(i)->scope()->monitors();
167 if (monitors != NULL) {
168 relock_objects(&deoptee, &map, monitors);
169 #ifndef PRODUCT
170 if (TraceDeoptimization) {
171 ttyLocker ttyl;
172 tty->print_cr("RELOCK OBJECTS in thread " INTPTR_FORMAT, thread);
173 for (int j = 0; j < monitors->length(); j++) {
174 MonitorValue* mv = monitors->at(j);
175 if (mv->eliminated()) {
176 StackValue* owner = StackValue::create_stack_value(&deoptee, &map, mv->owner());
177 tty->print_cr(" object <" INTPTR_FORMAT "> locked", owner->get_obj()());
178 }
179 }
180 }
181 #endif
182 }
183 }
184 }
185 }
186 #endif // COMPILER2
187 // Ensure that no safepoint is taken after pointers have been stored
188 // in fields of rematerialized objects. If a safepoint occurs from here on
189 // out the java state residing in the vframeArray will be missed.
190 No_Safepoint_Verifier no_safepoint;
192 vframeArray* array = create_vframeArray(thread, deoptee, &map, chunk);
194 assert(thread->vframe_array_head() == NULL, "Pending deopt!");;
195 thread->set_vframe_array_head(array);
197 // Now that the vframeArray has been created if we have any deferred local writes
198 // added by jvmti then we can free up that structure as the data is now in the
199 // vframeArray
201 if (thread->deferred_locals() != NULL) {
202 GrowableArray<jvmtiDeferredLocalVariableSet*>* list = thread->deferred_locals();
203 int i = 0;
204 do {
205 // Because of inlining we could have multiple vframes for a single frame
206 // and several of the vframes could have deferred writes. Find them all.
207 if (list->at(i)->id() == array->original().id()) {
208 jvmtiDeferredLocalVariableSet* dlv = list->at(i);
209 list->remove_at(i);
210 // individual jvmtiDeferredLocalVariableSet are CHeapObj's
211 delete dlv;
212 } else {
213 i++;
214 }
215 } while ( i < list->length() );
216 if (list->length() == 0) {
217 thread->set_deferred_locals(NULL);
218 // free the list and elements back to C heap.
219 delete list;
220 }
222 }
224 // Compute the caller frame based on the sender sp of stub_frame and stored frame sizes info.
225 CodeBlob* cb = stub_frame.cb();
226 // Verify we have the right vframeArray
227 assert(cb->frame_size() >= 0, "Unexpected frame size");
228 intptr_t* unpack_sp = stub_frame.sp() + cb->frame_size();
230 #ifdef ASSERT
231 assert(cb->is_deoptimization_stub() || cb->is_uncommon_trap_stub(), "just checking");
232 Events::log("fetch unroll sp " INTPTR_FORMAT, unpack_sp);
233 #endif
234 // This is a guarantee instead of an assert because if vframe doesn't match
235 // we will unpack the wrong deoptimized frame and wind up in strange places
236 // where it will be very difficult to figure out what went wrong. Better
237 // to die an early death here than some very obscure death later when the
238 // trail is cold.
239 // Note: on ia64 this guarantee can be fooled by frames with no memory stack
240 // in that it will fail to detect a problem when there is one. This needs
241 // more work in tiger timeframe.
242 guarantee(array->unextended_sp() == unpack_sp, "vframe_array_head must contain the vframeArray to unpack");
244 int number_of_frames = array->frames();
246 // Compute the vframes' sizes. Note that frame_sizes[] entries are ordered from outermost to innermost
247 // virtual activation, which is the reverse of the elements in the vframes array.
248 intptr_t* frame_sizes = NEW_C_HEAP_ARRAY(intptr_t, number_of_frames);
249 // +1 because we always have an interpreter return address for the final slot.
250 address* frame_pcs = NEW_C_HEAP_ARRAY(address, number_of_frames + 1);
251 int callee_parameters = 0;
252 int callee_locals = 0;
253 int popframe_extra_args = 0;
254 // Create an interpreter return address for the stub to use as its return
255 // address so the skeletal frames are perfectly walkable
256 frame_pcs[number_of_frames] = Interpreter::deopt_entry(vtos, 0);
258 // PopFrame requires that the preserved incoming arguments from the recently-popped topmost
259 // activation be put back on the expression stack of the caller for reexecution
260 if (JvmtiExport::can_pop_frame() && thread->popframe_forcing_deopt_reexecution()) {
261 popframe_extra_args = in_words(thread->popframe_preserved_args_size_in_words());
262 }
264 //
265 // frame_sizes/frame_pcs[0] oldest frame (int or c2i)
266 // frame_sizes/frame_pcs[1] next oldest frame (int)
267 // frame_sizes/frame_pcs[n] youngest frame (int)
268 //
269 // Now a pc in frame_pcs is actually the return address to the frame's caller (a frame
270 // owns the space for the return address to it's caller). Confusing ain't it.
271 //
272 // The vframe array can address vframes with indices running from
273 // 0.._frames-1. Index 0 is the youngest frame and _frame - 1 is the oldest (root) frame.
274 // When we create the skeletal frames we need the oldest frame to be in the zero slot
275 // in the frame_sizes/frame_pcs so the assembly code can do a trivial walk.
276 // so things look a little strange in this loop.
277 //
278 for (int index = 0; index < array->frames(); index++ ) {
279 // frame[number_of_frames - 1 ] = on_stack_size(youngest)
280 // frame[number_of_frames - 2 ] = on_stack_size(sender(youngest))
281 // frame[number_of_frames - 3 ] = on_stack_size(sender(sender(youngest)))
282 frame_sizes[number_of_frames - 1 - index] = BytesPerWord * array->element(index)->on_stack_size(callee_parameters,
283 callee_locals,
284 index == 0,
285 popframe_extra_args);
286 // This pc doesn't have to be perfect just good enough to identify the frame
287 // as interpreted so the skeleton frame will be walkable
288 // The correct pc will be set when the skeleton frame is completely filled out
289 // The final pc we store in the loop is wrong and will be overwritten below
290 frame_pcs[number_of_frames - 1 - index ] = Interpreter::deopt_entry(vtos, 0) - frame::pc_return_offset;
292 callee_parameters = array->element(index)->method()->size_of_parameters();
293 callee_locals = array->element(index)->method()->max_locals();
294 popframe_extra_args = 0;
295 }
297 // Compute whether the root vframe returns a float or double value.
298 BasicType return_type;
299 {
300 HandleMark hm;
301 methodHandle method(thread, array->element(0)->method());
302 Bytecode_invoke* invoke = Bytecode_invoke_at_check(method, array->element(0)->bci());
303 return_type = (invoke != NULL) ? invoke->result_type(thread) : T_ILLEGAL;
304 }
306 // Compute information for handling adapters and adjusting the frame size of the caller.
307 int caller_adjustment = 0;
309 // Find the current pc for sender of the deoptee. Since the sender may have been deoptimized
310 // itself since the deoptee vframeArray was created we must get a fresh value of the pc rather
311 // than simply use array->sender.pc(). This requires us to walk the current set of frames
312 //
313 frame deopt_sender = stub_frame.sender(&dummy_map); // First is the deoptee frame
314 deopt_sender = deopt_sender.sender(&dummy_map); // Now deoptee caller
316 // Compute the amount the oldest interpreter frame will have to adjust
317 // its caller's stack by. If the caller is a compiled frame then
318 // we pretend that the callee has no parameters so that the
319 // extension counts for the full amount of locals and not just
320 // locals-parms. This is because without a c2i adapter the parm
321 // area as created by the compiled frame will not be usable by
322 // the interpreter. (Depending on the calling convention there
323 // may not even be enough space).
325 // QQQ I'd rather see this pushed down into last_frame_adjust
326 // and have it take the sender (aka caller).
328 if (deopt_sender.is_compiled_frame()) {
329 caller_adjustment = last_frame_adjust(0, callee_locals);
330 } else if (callee_locals > callee_parameters) {
331 // The caller frame may need extending to accommodate
332 // non-parameter locals of the first unpacked interpreted frame.
333 // Compute that adjustment.
334 caller_adjustment = last_frame_adjust(callee_parameters, callee_locals);
335 }
338 // If the sender is deoptimized the we must retrieve the address of the handler
339 // since the frame will "magically" show the original pc before the deopt
340 // and we'd undo the deopt.
342 frame_pcs[0] = deopt_sender.raw_pc();
344 assert(CodeCache::find_blob_unsafe(frame_pcs[0]) != NULL, "bad pc");
346 UnrollBlock* info = new UnrollBlock(array->frame_size() * BytesPerWord,
347 caller_adjustment * BytesPerWord,
348 number_of_frames,
349 frame_sizes,
350 frame_pcs,
351 return_type);
352 #if defined(IA32) || defined(AMD64)
353 // We need a way to pass fp to the unpacking code so the skeletal frames
354 // come out correct. This is only needed for x86 because of c2 using ebp
355 // as an allocatable register. So this update is useless (and harmless)
356 // on the other platforms. It would be nice to do this in a different
357 // way but even the old style deoptimization had a problem with deriving
358 // this value. NEEDS_CLEANUP
359 // Note: now that c1 is using c2's deopt blob we must do this on all
360 // x86 based platforms
361 intptr_t** fp_addr = (intptr_t**) (((address)info) + info->initial_fp_offset_in_bytes());
362 *fp_addr = array->sender().fp(); // was adapter_caller
363 #endif /* IA32 || AMD64 */
365 if (array->frames() > 1) {
366 if (VerifyStack && TraceDeoptimization) {
367 tty->print_cr("Deoptimizing method containing inlining");
368 }
369 }
371 array->set_unroll_block(info);
372 return info;
373 }
375 // Called to cleanup deoptimization data structures in normal case
376 // after unpacking to stack and when stack overflow error occurs
377 void Deoptimization::cleanup_deopt_info(JavaThread *thread,
378 vframeArray *array) {
380 // Get array if coming from exception
381 if (array == NULL) {
382 array = thread->vframe_array_head();
383 }
384 thread->set_vframe_array_head(NULL);
386 // Free the previous UnrollBlock
387 vframeArray* old_array = thread->vframe_array_last();
388 thread->set_vframe_array_last(array);
390 if (old_array != NULL) {
391 UnrollBlock* old_info = old_array->unroll_block();
392 old_array->set_unroll_block(NULL);
393 delete old_info;
394 delete old_array;
395 }
397 // Deallocate any resource creating in this routine and any ResourceObjs allocated
398 // inside the vframeArray (StackValueCollections)
400 delete thread->deopt_mark();
401 thread->set_deopt_mark(NULL);
404 if (JvmtiExport::can_pop_frame()) {
405 #ifndef CC_INTERP
406 // Regardless of whether we entered this routine with the pending
407 // popframe condition bit set, we should always clear it now
408 thread->clear_popframe_condition();
409 #else
410 // C++ interpeter will clear has_pending_popframe when it enters
411 // with method_resume. For deopt_resume2 we clear it now.
412 if (thread->popframe_forcing_deopt_reexecution())
413 thread->clear_popframe_condition();
414 #endif /* CC_INTERP */
415 }
417 // unpack_frames() is called at the end of the deoptimization handler
418 // and (in C2) at the end of the uncommon trap handler. Note this fact
419 // so that an asynchronous stack walker can work again. This counter is
420 // incremented at the beginning of fetch_unroll_info() and (in C2) at
421 // the beginning of uncommon_trap().
422 thread->dec_in_deopt_handler();
423 }
426 // Return BasicType of value being returned
427 JRT_LEAF(BasicType, Deoptimization::unpack_frames(JavaThread* thread, int exec_mode))
429 // We are already active int he special DeoptResourceMark any ResourceObj's we
430 // allocate will be freed at the end of the routine.
432 // It is actually ok to allocate handles in a leaf method. It causes no safepoints,
433 // but makes the entry a little slower. There is however a little dance we have to
434 // do in debug mode to get around the NoHandleMark code in the JRT_LEAF macro
435 ResetNoHandleMark rnhm; // No-op in release/product versions
436 HandleMark hm;
438 frame stub_frame = thread->last_frame();
440 // Since the frame to unpack is the top frame of this thread, the vframe_array_head
441 // must point to the vframeArray for the unpack frame.
442 vframeArray* array = thread->vframe_array_head();
444 #ifndef PRODUCT
445 if (TraceDeoptimization) {
446 tty->print_cr("DEOPT UNPACKING thread " INTPTR_FORMAT " vframeArray " INTPTR_FORMAT " mode %d", thread, array, exec_mode);
447 }
448 #endif
450 UnrollBlock* info = array->unroll_block();
452 // Unpack the interpreter frames and any adapter frame (c2 only) we might create.
453 array->unpack_to_stack(stub_frame, exec_mode);
455 BasicType bt = info->return_type();
457 // If we have an exception pending, claim that the return type is an oop
458 // so the deopt_blob does not overwrite the exception_oop.
460 if (exec_mode == Unpack_exception)
461 bt = T_OBJECT;
463 // Cleanup thread deopt data
464 cleanup_deopt_info(thread, array);
466 #ifndef PRODUCT
467 if (VerifyStack) {
468 ResourceMark res_mark;
470 // Verify that the just-unpacked frames match the interpreter's
471 // notions of expression stack and locals
472 vframeArray* cur_array = thread->vframe_array_last();
473 RegisterMap rm(thread, false);
474 rm.set_include_argument_oops(false);
475 bool is_top_frame = true;
476 int callee_size_of_parameters = 0;
477 int callee_max_locals = 0;
478 for (int i = 0; i < cur_array->frames(); i++) {
479 vframeArrayElement* el = cur_array->element(i);
480 frame* iframe = el->iframe();
481 guarantee(iframe->is_interpreted_frame(), "Wrong frame type");
483 // Get the oop map for this bci
484 InterpreterOopMap mask;
485 int cur_invoke_parameter_size = 0;
486 bool try_next_mask = false;
487 int next_mask_expression_stack_size = -1;
488 int top_frame_expression_stack_adjustment = 0;
489 methodHandle mh(thread, iframe->interpreter_frame_method());
490 OopMapCache::compute_one_oop_map(mh, iframe->interpreter_frame_bci(), &mask);
491 BytecodeStream str(mh);
492 str.set_start(iframe->interpreter_frame_bci());
493 int max_bci = mh->code_size();
494 // Get to the next bytecode if possible
495 assert(str.bci() < max_bci, "bci in interpreter frame out of bounds");
496 // Check to see if we can grab the number of outgoing arguments
497 // at an uncommon trap for an invoke (where the compiler
498 // generates debug info before the invoke has executed)
499 Bytecodes::Code cur_code = str.next();
500 if (cur_code == Bytecodes::_invokevirtual ||
501 cur_code == Bytecodes::_invokespecial ||
502 cur_code == Bytecodes::_invokestatic ||
503 cur_code == Bytecodes::_invokeinterface) {
504 Bytecode_invoke* invoke = Bytecode_invoke_at(mh, iframe->interpreter_frame_bci());
505 symbolHandle signature(thread, invoke->signature());
506 ArgumentSizeComputer asc(signature);
507 cur_invoke_parameter_size = asc.size();
508 if (cur_code != Bytecodes::_invokestatic) {
509 // Add in receiver
510 ++cur_invoke_parameter_size;
511 }
512 }
513 if (str.bci() < max_bci) {
514 Bytecodes::Code bc = str.next();
515 if (bc >= 0) {
516 // The interpreter oop map generator reports results before
517 // the current bytecode has executed except in the case of
518 // calls. It seems to be hard to tell whether the compiler
519 // has emitted debug information matching the "state before"
520 // a given bytecode or the state after, so we try both
521 switch (cur_code) {
522 case Bytecodes::_invokevirtual:
523 case Bytecodes::_invokespecial:
524 case Bytecodes::_invokestatic:
525 case Bytecodes::_invokeinterface:
526 case Bytecodes::_athrow:
527 break;
528 default: {
529 InterpreterOopMap next_mask;
530 OopMapCache::compute_one_oop_map(mh, str.bci(), &next_mask);
531 next_mask_expression_stack_size = next_mask.expression_stack_size();
532 // Need to subtract off the size of the result type of
533 // the bytecode because this is not described in the
534 // debug info but returned to the interpreter in the TOS
535 // caching register
536 BasicType bytecode_result_type = Bytecodes::result_type(cur_code);
537 if (bytecode_result_type != T_ILLEGAL) {
538 top_frame_expression_stack_adjustment = type2size[bytecode_result_type];
539 }
540 assert(top_frame_expression_stack_adjustment >= 0, "");
541 try_next_mask = true;
542 break;
543 }
544 }
545 }
546 }
548 // Verify stack depth and oops in frame
549 // This assertion may be dependent on the platform we're running on and may need modification (tested on x86 and sparc)
550 if (!(
551 /* SPARC */
552 (iframe->interpreter_frame_expression_stack_size() == mask.expression_stack_size() + callee_size_of_parameters) ||
553 /* x86 */
554 (iframe->interpreter_frame_expression_stack_size() == mask.expression_stack_size() + callee_max_locals) ||
555 (try_next_mask &&
556 (iframe->interpreter_frame_expression_stack_size() == (next_mask_expression_stack_size -
557 top_frame_expression_stack_adjustment))) ||
558 (is_top_frame && (exec_mode == Unpack_exception) && iframe->interpreter_frame_expression_stack_size() == 0) ||
559 (is_top_frame && (exec_mode == Unpack_uncommon_trap || exec_mode == Unpack_reexecute) &&
560 (iframe->interpreter_frame_expression_stack_size() == mask.expression_stack_size() + cur_invoke_parameter_size))
561 )) {
562 ttyLocker ttyl;
564 // Print out some information that will help us debug the problem
565 tty->print_cr("Wrong number of expression stack elements during deoptimization");
566 tty->print_cr(" Error occurred while verifying frame %d (0..%d, 0 is topmost)", i, cur_array->frames() - 1);
567 tty->print_cr(" Fabricated interpreter frame had %d expression stack elements",
568 iframe->interpreter_frame_expression_stack_size());
569 tty->print_cr(" Interpreter oop map had %d expression stack elements", mask.expression_stack_size());
570 tty->print_cr(" try_next_mask = %d", try_next_mask);
571 tty->print_cr(" next_mask_expression_stack_size = %d", next_mask_expression_stack_size);
572 tty->print_cr(" callee_size_of_parameters = %d", callee_size_of_parameters);
573 tty->print_cr(" callee_max_locals = %d", callee_max_locals);
574 tty->print_cr(" top_frame_expression_stack_adjustment = %d", top_frame_expression_stack_adjustment);
575 tty->print_cr(" exec_mode = %d", exec_mode);
576 tty->print_cr(" cur_invoke_parameter_size = %d", cur_invoke_parameter_size);
577 tty->print_cr(" Thread = " INTPTR_FORMAT ", thread ID = " UINTX_FORMAT, thread, thread->osthread()->thread_id());
578 tty->print_cr(" Interpreted frames:");
579 for (int k = 0; k < cur_array->frames(); k++) {
580 vframeArrayElement* el = cur_array->element(k);
581 tty->print_cr(" %s (bci %d)", el->method()->name_and_sig_as_C_string(), el->bci());
582 }
583 cur_array->print_on_2(tty);
584 guarantee(false, "wrong number of expression stack elements during deopt");
585 }
586 VerifyOopClosure verify;
587 iframe->oops_interpreted_do(&verify, &rm, false);
588 callee_size_of_parameters = mh->size_of_parameters();
589 callee_max_locals = mh->max_locals();
590 is_top_frame = false;
591 }
592 }
593 #endif /* !PRODUCT */
596 return bt;
597 JRT_END
600 int Deoptimization::deoptimize_dependents() {
601 Threads::deoptimized_wrt_marked_nmethods();
602 return 0;
603 }
606 #ifdef COMPILER2
607 bool Deoptimization::realloc_objects(JavaThread* thread, frame* fr, GrowableArray<ScopeValue*>* objects, TRAPS) {
608 Handle pending_exception(thread->pending_exception());
609 const char* exception_file = thread->exception_file();
610 int exception_line = thread->exception_line();
611 thread->clear_pending_exception();
613 for (int i = 0; i < objects->length(); i++) {
614 assert(objects->at(i)->is_object(), "invalid debug information");
615 ObjectValue* sv = (ObjectValue*) objects->at(i);
617 KlassHandle k(((ConstantOopReadValue*) sv->klass())->value()());
618 oop obj = NULL;
620 if (k->oop_is_instance()) {
621 instanceKlass* ik = instanceKlass::cast(k());
622 obj = ik->allocate_instance(CHECK_(false));
623 } else if (k->oop_is_typeArray()) {
624 typeArrayKlass* ak = typeArrayKlass::cast(k());
625 assert(sv->field_size() % type2size[ak->element_type()] == 0, "non-integral array length");
626 int len = sv->field_size() / type2size[ak->element_type()];
627 obj = ak->allocate(len, CHECK_(false));
628 } else if (k->oop_is_objArray()) {
629 objArrayKlass* ak = objArrayKlass::cast(k());
630 obj = ak->allocate(sv->field_size(), CHECK_(false));
631 }
633 assert(obj != NULL, "allocation failed");
634 assert(sv->value().is_null(), "redundant reallocation");
635 sv->set_value(obj);
636 }
638 if (pending_exception.not_null()) {
639 thread->set_pending_exception(pending_exception(), exception_file, exception_line);
640 }
642 return true;
643 }
645 // This assumes that the fields are stored in ObjectValue in the same order
646 // they are yielded by do_nonstatic_fields.
647 class FieldReassigner: public FieldClosure {
648 frame* _fr;
649 RegisterMap* _reg_map;
650 ObjectValue* _sv;
651 instanceKlass* _ik;
652 oop _obj;
654 int _i;
655 public:
656 FieldReassigner(frame* fr, RegisterMap* reg_map, ObjectValue* sv, oop obj) :
657 _fr(fr), _reg_map(reg_map), _sv(sv), _obj(obj), _i(0) {}
659 int i() const { return _i; }
662 void do_field(fieldDescriptor* fd) {
663 intptr_t val;
664 StackValue* value =
665 StackValue::create_stack_value(_fr, _reg_map, _sv->field_at(i()));
666 int offset = fd->offset();
667 switch (fd->field_type()) {
668 case T_OBJECT: case T_ARRAY:
669 assert(value->type() == T_OBJECT, "Agreement.");
670 _obj->obj_field_put(offset, value->get_obj()());
671 break;
673 case T_LONG: case T_DOUBLE: {
674 assert(value->type() == T_INT, "Agreement.");
675 StackValue* low =
676 StackValue::create_stack_value(_fr, _reg_map, _sv->field_at(++_i));
677 #ifdef _LP64
678 jlong res = (jlong)low->get_int();
679 #else
680 #ifdef SPARC
681 // For SPARC we have to swap high and low words.
682 jlong res = jlong_from((jint)low->get_int(), (jint)value->get_int());
683 #else
684 jlong res = jlong_from((jint)value->get_int(), (jint)low->get_int());
685 #endif //SPARC
686 #endif
687 _obj->long_field_put(offset, res);
688 break;
689 }
690 // Have to cast to INT (32 bits) pointer to avoid little/big-endian problem.
691 case T_INT: case T_FLOAT: // 4 bytes.
692 assert(value->type() == T_INT, "Agreement.");
693 val = value->get_int();
694 _obj->int_field_put(offset, (jint)*((jint*)&val));
695 break;
697 case T_SHORT: case T_CHAR: // 2 bytes
698 assert(value->type() == T_INT, "Agreement.");
699 val = value->get_int();
700 _obj->short_field_put(offset, (jshort)*((jint*)&val));
701 break;
703 case T_BOOLEAN: case T_BYTE: // 1 byte
704 assert(value->type() == T_INT, "Agreement.");
705 val = value->get_int();
706 _obj->bool_field_put(offset, (jboolean)*((jint*)&val));
707 break;
709 default:
710 ShouldNotReachHere();
711 }
712 _i++;
713 }
714 };
716 // restore elements of an eliminated type array
717 void Deoptimization::reassign_type_array_elements(frame* fr, RegisterMap* reg_map, ObjectValue* sv, typeArrayOop obj, BasicType type) {
718 int index = 0;
719 intptr_t val;
721 for (int i = 0; i < sv->field_size(); i++) {
722 StackValue* value = StackValue::create_stack_value(fr, reg_map, sv->field_at(i));
723 switch(type) {
724 case T_LONG: case T_DOUBLE: {
725 assert(value->type() == T_INT, "Agreement.");
726 StackValue* low =
727 StackValue::create_stack_value(fr, reg_map, sv->field_at(++i));
728 #ifdef _LP64
729 jlong res = (jlong)low->get_int();
730 #else
731 #ifdef SPARC
732 // For SPARC we have to swap high and low words.
733 jlong res = jlong_from((jint)low->get_int(), (jint)value->get_int());
734 #else
735 jlong res = jlong_from((jint)value->get_int(), (jint)low->get_int());
736 #endif //SPARC
737 #endif
738 obj->long_at_put(index, res);
739 break;
740 }
742 // Have to cast to INT (32 bits) pointer to avoid little/big-endian problem.
743 case T_INT: case T_FLOAT: // 4 bytes.
744 assert(value->type() == T_INT, "Agreement.");
745 val = value->get_int();
746 obj->int_at_put(index, (jint)*((jint*)&val));
747 break;
749 case T_SHORT: case T_CHAR: // 2 bytes
750 assert(value->type() == T_INT, "Agreement.");
751 val = value->get_int();
752 obj->short_at_put(index, (jshort)*((jint*)&val));
753 break;
755 case T_BOOLEAN: case T_BYTE: // 1 byte
756 assert(value->type() == T_INT, "Agreement.");
757 val = value->get_int();
758 obj->bool_at_put(index, (jboolean)*((jint*)&val));
759 break;
761 default:
762 ShouldNotReachHere();
763 }
764 index++;
765 }
766 }
769 // restore fields of an eliminated object array
770 void Deoptimization::reassign_object_array_elements(frame* fr, RegisterMap* reg_map, ObjectValue* sv, objArrayOop obj) {
771 for (int i = 0; i < sv->field_size(); i++) {
772 StackValue* value = StackValue::create_stack_value(fr, reg_map, sv->field_at(i));
773 assert(value->type() == T_OBJECT, "object element expected");
774 obj->obj_at_put(i, value->get_obj()());
775 }
776 }
779 // restore fields of all eliminated objects and arrays
780 void Deoptimization::reassign_fields(frame* fr, RegisterMap* reg_map, GrowableArray<ScopeValue*>* objects) {
781 for (int i = 0; i < objects->length(); i++) {
782 ObjectValue* sv = (ObjectValue*) objects->at(i);
783 KlassHandle k(((ConstantOopReadValue*) sv->klass())->value()());
784 Handle obj = sv->value();
785 assert(obj.not_null(), "reallocation was missed");
787 if (k->oop_is_instance()) {
788 instanceKlass* ik = instanceKlass::cast(k());
789 FieldReassigner reassign(fr, reg_map, sv, obj());
790 ik->do_nonstatic_fields(&reassign);
791 } else if (k->oop_is_typeArray()) {
792 typeArrayKlass* ak = typeArrayKlass::cast(k());
793 reassign_type_array_elements(fr, reg_map, sv, (typeArrayOop) obj(), ak->element_type());
794 } else if (k->oop_is_objArray()) {
795 reassign_object_array_elements(fr, reg_map, sv, (objArrayOop) obj());
796 }
797 }
798 }
801 // relock objects for which synchronization was eliminated
802 void Deoptimization::relock_objects(frame* fr, RegisterMap* reg_map, GrowableArray<MonitorValue*>* monitors) {
803 for (int i = 0; i < monitors->length(); i++) {
804 MonitorValue* mv = monitors->at(i);
805 StackValue* owner = StackValue::create_stack_value(fr, reg_map, mv->owner());
806 if (mv->eliminated()) {
807 Handle obj = owner->get_obj();
808 assert(obj.not_null(), "reallocation was missed");
809 BasicLock* lock = StackValue::resolve_monitor_lock(fr, mv->basic_lock());
810 lock->set_displaced_header(obj->mark());
811 obj->set_mark((markOop) lock);
812 }
813 assert(owner->get_obj()->is_locked(), "object must be locked now");
814 }
815 }
818 #ifndef PRODUCT
819 // print information about reallocated objects
820 void Deoptimization::print_objects(GrowableArray<ScopeValue*>* objects) {
821 fieldDescriptor fd;
823 for (int i = 0; i < objects->length(); i++) {
824 ObjectValue* sv = (ObjectValue*) objects->at(i);
825 KlassHandle k(((ConstantOopReadValue*) sv->klass())->value()());
826 Handle obj = sv->value();
828 tty->print(" object <" INTPTR_FORMAT "> of type ", sv->value()());
829 k->as_klassOop()->print_value();
830 tty->print(" allocated (%d bytes)", obj->size() * HeapWordSize);
831 tty->cr();
833 if (Verbose) {
834 k->oop_print_on(obj(), tty);
835 }
836 }
837 }
838 #endif
839 #endif // COMPILER2
841 vframeArray* Deoptimization::create_vframeArray(JavaThread* thread, frame fr, RegisterMap *reg_map, GrowableArray<compiledVFrame*>* chunk) {
843 #ifndef PRODUCT
844 if (TraceDeoptimization) {
845 ttyLocker ttyl;
846 tty->print("DEOPT PACKING thread " INTPTR_FORMAT " ", thread);
847 fr.print_on(tty);
848 tty->print_cr(" Virtual frames (innermost first):");
849 for (int index = 0; index < chunk->length(); index++) {
850 compiledVFrame* vf = chunk->at(index);
851 tty->print(" %2d - ", index);
852 vf->print_value();
853 int bci = chunk->at(index)->raw_bci();
854 const char* code_name;
855 if (bci == SynchronizationEntryBCI) {
856 code_name = "sync entry";
857 } else {
858 Bytecodes::Code code = Bytecodes::code_at(vf->method(), bci);
859 code_name = Bytecodes::name(code);
860 }
861 tty->print(" - %s", code_name);
862 tty->print_cr(" @ bci %d ", bci);
863 if (Verbose) {
864 vf->print();
865 tty->cr();
866 }
867 }
868 }
869 #endif
871 // Register map for next frame (used for stack crawl). We capture
872 // the state of the deopt'ing frame's caller. Thus if we need to
873 // stuff a C2I adapter we can properly fill in the callee-save
874 // register locations.
875 frame caller = fr.sender(reg_map);
876 int frame_size = caller.sp() - fr.sp();
878 frame sender = caller;
880 // Since the Java thread being deoptimized will eventually adjust it's own stack,
881 // the vframeArray containing the unpacking information is allocated in the C heap.
882 // For Compiler1, the caller of the deoptimized frame is saved for use by unpack_frames().
883 vframeArray* array = vframeArray::allocate(thread, frame_size, chunk, reg_map, sender, caller, fr);
885 // Compare the vframeArray to the collected vframes
886 assert(array->structural_compare(thread, chunk), "just checking");
887 Events::log("# vframes = %d", (intptr_t)chunk->length());
889 #ifndef PRODUCT
890 if (TraceDeoptimization) {
891 ttyLocker ttyl;
892 tty->print_cr(" Created vframeArray " INTPTR_FORMAT, array);
893 if (Verbose) {
894 int count = 0;
895 // this used to leak deoptimizedVFrame like it was going out of style!!!
896 for (int index = 0; index < array->frames(); index++ ) {
897 vframeArrayElement* e = array->element(index);
898 e->print(tty);
900 /*
901 No printing yet.
902 array->vframe_at(index)->print_activation(count++);
903 // better as...
904 array->print_activation_for(index, count++);
905 */
906 }
907 }
908 }
909 #endif // PRODUCT
911 return array;
912 }
915 static void collect_monitors(compiledVFrame* cvf, GrowableArray<Handle>* objects_to_revoke) {
916 GrowableArray<MonitorInfo*>* monitors = cvf->monitors();
917 for (int i = 0; i < monitors->length(); i++) {
918 MonitorInfo* mon_info = monitors->at(i);
919 if (mon_info->owner() != NULL) {
920 objects_to_revoke->append(Handle(mon_info->owner()));
921 }
922 }
923 }
926 void Deoptimization::revoke_biases_of_monitors(JavaThread* thread, frame fr, RegisterMap* map) {
927 if (!UseBiasedLocking) {
928 return;
929 }
931 GrowableArray<Handle>* objects_to_revoke = new GrowableArray<Handle>();
933 // Unfortunately we don't have a RegisterMap available in most of
934 // the places we want to call this routine so we need to walk the
935 // stack again to update the register map.
936 if (map == NULL || !map->update_map()) {
937 StackFrameStream sfs(thread, true);
938 bool found = false;
939 while (!found && !sfs.is_done()) {
940 frame* cur = sfs.current();
941 sfs.next();
942 found = cur->id() == fr.id();
943 }
944 assert(found, "frame to be deoptimized not found on target thread's stack");
945 map = sfs.register_map();
946 }
948 vframe* vf = vframe::new_vframe(&fr, map, thread);
949 compiledVFrame* cvf = compiledVFrame::cast(vf);
950 // Revoke monitors' biases in all scopes
951 while (!cvf->is_top()) {
952 collect_monitors(cvf, objects_to_revoke);
953 cvf = compiledVFrame::cast(cvf->sender());
954 }
955 collect_monitors(cvf, objects_to_revoke);
957 if (SafepointSynchronize::is_at_safepoint()) {
958 BiasedLocking::revoke_at_safepoint(objects_to_revoke);
959 } else {
960 BiasedLocking::revoke(objects_to_revoke);
961 }
962 }
965 void Deoptimization::revoke_biases_of_monitors(CodeBlob* cb) {
966 if (!UseBiasedLocking) {
967 return;
968 }
970 assert(SafepointSynchronize::is_at_safepoint(), "must only be called from safepoint");
971 GrowableArray<Handle>* objects_to_revoke = new GrowableArray<Handle>();
972 for (JavaThread* jt = Threads::first(); jt != NULL ; jt = jt->next()) {
973 if (jt->has_last_Java_frame()) {
974 StackFrameStream sfs(jt, true);
975 while (!sfs.is_done()) {
976 frame* cur = sfs.current();
977 if (cb->contains(cur->pc())) {
978 vframe* vf = vframe::new_vframe(cur, sfs.register_map(), jt);
979 compiledVFrame* cvf = compiledVFrame::cast(vf);
980 // Revoke monitors' biases in all scopes
981 while (!cvf->is_top()) {
982 collect_monitors(cvf, objects_to_revoke);
983 cvf = compiledVFrame::cast(cvf->sender());
984 }
985 collect_monitors(cvf, objects_to_revoke);
986 }
987 sfs.next();
988 }
989 }
990 }
991 BiasedLocking::revoke_at_safepoint(objects_to_revoke);
992 }
995 void Deoptimization::deoptimize_single_frame(JavaThread* thread, frame fr) {
996 assert(fr.can_be_deoptimized(), "checking frame type");
998 gather_statistics(Reason_constraint, Action_none, Bytecodes::_illegal);
1000 EventMark m("Deoptimization (pc=" INTPTR_FORMAT ", sp=" INTPTR_FORMAT ")", fr.pc(), fr.id());
1002 // Patch the nmethod so that when execution returns to it we will
1003 // deopt the execution state and return to the interpreter.
1004 fr.deoptimize(thread);
1005 }
1007 void Deoptimization::deoptimize(JavaThread* thread, frame fr, RegisterMap *map) {
1008 // Deoptimize only if the frame comes from compile code.
1009 // Do not deoptimize the frame which is already patched
1010 // during the execution of the loops below.
1011 if (!fr.is_compiled_frame() || fr.is_deoptimized_frame()) {
1012 return;
1013 }
1014 ResourceMark rm;
1015 DeoptimizationMarker dm;
1016 if (UseBiasedLocking) {
1017 revoke_biases_of_monitors(thread, fr, map);
1018 }
1019 deoptimize_single_frame(thread, fr);
1021 }
1024 void Deoptimization::deoptimize_frame(JavaThread* thread, intptr_t* id) {
1025 // Compute frame and register map based on thread and sp.
1026 RegisterMap reg_map(thread, UseBiasedLocking);
1027 frame fr = thread->last_frame();
1028 while (fr.id() != id) {
1029 fr = fr.sender(®_map);
1030 }
1031 deoptimize(thread, fr, ®_map);
1032 }
1035 // JVMTI PopFrame support
1036 JRT_LEAF(void, Deoptimization::popframe_preserve_args(JavaThread* thread, int bytes_to_save, void* start_address))
1037 {
1038 thread->popframe_preserve_args(in_ByteSize(bytes_to_save), start_address);
1039 }
1040 JRT_END
1043 #ifdef COMPILER2
1044 void Deoptimization::load_class_by_index(constantPoolHandle constant_pool, int index, TRAPS) {
1045 // in case of an unresolved klass entry, load the class.
1046 if (constant_pool->tag_at(index).is_unresolved_klass()) {
1047 klassOop tk = constant_pool->klass_at(index, CHECK);
1048 return;
1049 }
1051 if (!constant_pool->tag_at(index).is_symbol()) return;
1053 Handle class_loader (THREAD, instanceKlass::cast(constant_pool->pool_holder())->class_loader());
1054 symbolHandle symbol (THREAD, constant_pool->symbol_at(index));
1056 // class name?
1057 if (symbol->byte_at(0) != '(') {
1058 Handle protection_domain (THREAD, Klass::cast(constant_pool->pool_holder())->protection_domain());
1059 SystemDictionary::resolve_or_null(symbol, class_loader, protection_domain, CHECK);
1060 return;
1061 }
1063 // then it must be a signature!
1064 for (SignatureStream ss(symbol); !ss.is_done(); ss.next()) {
1065 if (ss.is_object()) {
1066 symbolOop s = ss.as_symbol(CHECK);
1067 symbolHandle class_name (THREAD, s);
1068 Handle protection_domain (THREAD, Klass::cast(constant_pool->pool_holder())->protection_domain());
1069 SystemDictionary::resolve_or_null(class_name, class_loader, protection_domain, CHECK);
1070 }
1071 }
1072 }
1075 void Deoptimization::load_class_by_index(constantPoolHandle constant_pool, int index) {
1076 EXCEPTION_MARK;
1077 load_class_by_index(constant_pool, index, THREAD);
1078 if (HAS_PENDING_EXCEPTION) {
1079 // Exception happened during classloading. We ignore the exception here, since it
1080 // is going to be rethrown since the current activation is going to be deoptimzied and
1081 // the interpreter will re-execute the bytecode.
1082 CLEAR_PENDING_EXCEPTION;
1083 }
1084 }
1086 JRT_ENTRY(void, Deoptimization::uncommon_trap_inner(JavaThread* thread, jint trap_request)) {
1087 HandleMark hm;
1089 // uncommon_trap() is called at the beginning of the uncommon trap
1090 // handler. Note this fact before we start generating temporary frames
1091 // that can confuse an asynchronous stack walker. This counter is
1092 // decremented at the end of unpack_frames().
1093 thread->inc_in_deopt_handler();
1095 // We need to update the map if we have biased locking.
1096 RegisterMap reg_map(thread, UseBiasedLocking);
1097 frame stub_frame = thread->last_frame();
1098 frame fr = stub_frame.sender(®_map);
1099 // Make sure the calling nmethod is not getting deoptimized and removed
1100 // before we are done with it.
1101 nmethodLocker nl(fr.pc());
1103 {
1104 ResourceMark rm;
1106 // Revoke biases of any monitors in the frame to ensure we can migrate them
1107 revoke_biases_of_monitors(thread, fr, ®_map);
1109 DeoptReason reason = trap_request_reason(trap_request);
1110 DeoptAction action = trap_request_action(trap_request);
1111 jint unloaded_class_index = trap_request_index(trap_request); // CP idx or -1
1113 Events::log("Uncommon trap occurred @" INTPTR_FORMAT " unloaded_class_index = %d", fr.pc(), (int) trap_request);
1114 vframe* vf = vframe::new_vframe(&fr, ®_map, thread);
1115 compiledVFrame* cvf = compiledVFrame::cast(vf);
1117 nmethod* nm = cvf->code();
1119 ScopeDesc* trap_scope = cvf->scope();
1120 methodHandle trap_method = trap_scope->method();
1121 int trap_bci = trap_scope->bci();
1122 Bytecodes::Code trap_bc = Bytecode_at(trap_method->bcp_from(trap_bci))->java_code();
1124 // Record this event in the histogram.
1125 gather_statistics(reason, action, trap_bc);
1127 // Ensure that we can record deopt. history:
1128 bool create_if_missing = ProfileTraps;
1130 methodDataHandle trap_mdo
1131 (THREAD, get_method_data(thread, trap_method, create_if_missing));
1133 // Print a bunch of diagnostics, if requested.
1134 if (TraceDeoptimization || LogCompilation) {
1135 ResourceMark rm;
1136 ttyLocker ttyl;
1137 char buf[100];
1138 if (xtty != NULL) {
1139 xtty->begin_head("uncommon_trap thread='" UINTX_FORMAT"' %s",
1140 os::current_thread_id(),
1141 format_trap_request(buf, sizeof(buf), trap_request));
1142 nm->log_identity(xtty);
1143 }
1144 symbolHandle class_name;
1145 bool unresolved = false;
1146 if (unloaded_class_index >= 0) {
1147 constantPoolHandle constants (THREAD, trap_method->constants());
1148 if (constants->tag_at(unloaded_class_index).is_unresolved_klass()) {
1149 class_name = symbolHandle(THREAD,
1150 constants->klass_name_at(unloaded_class_index));
1151 unresolved = true;
1152 if (xtty != NULL)
1153 xtty->print(" unresolved='1'");
1154 } else if (constants->tag_at(unloaded_class_index).is_symbol()) {
1155 class_name = symbolHandle(THREAD,
1156 constants->symbol_at(unloaded_class_index));
1157 }
1158 if (xtty != NULL)
1159 xtty->name(class_name);
1160 }
1161 if (xtty != NULL && trap_mdo.not_null()) {
1162 // Dump the relevant MDO state.
1163 // This is the deopt count for the current reason, any previous
1164 // reasons or recompiles seen at this point.
1165 int dcnt = trap_mdo->trap_count(reason);
1166 if (dcnt != 0)
1167 xtty->print(" count='%d'", dcnt);
1168 ProfileData* pdata = trap_mdo->bci_to_data(trap_bci);
1169 int dos = (pdata == NULL)? 0: pdata->trap_state();
1170 if (dos != 0) {
1171 xtty->print(" state='%s'", format_trap_state(buf, sizeof(buf), dos));
1172 if (trap_state_is_recompiled(dos)) {
1173 int recnt2 = trap_mdo->overflow_recompile_count();
1174 if (recnt2 != 0)
1175 xtty->print(" recompiles2='%d'", recnt2);
1176 }
1177 }
1178 }
1179 if (xtty != NULL) {
1180 xtty->stamp();
1181 xtty->end_head();
1182 }
1183 if (TraceDeoptimization) { // make noise on the tty
1184 tty->print("Uncommon trap occurred in");
1185 nm->method()->print_short_name(tty);
1186 tty->print(" (@" INTPTR_FORMAT ") thread=%d reason=%s action=%s unloaded_class_index=%d",
1187 fr.pc(),
1188 (int) os::current_thread_id(),
1189 trap_reason_name(reason),
1190 trap_action_name(action),
1191 unloaded_class_index);
1192 if (class_name.not_null()) {
1193 tty->print(unresolved ? " unresolved class: " : " symbol: ");
1194 class_name->print_symbol_on(tty);
1195 }
1196 tty->cr();
1197 }
1198 if (xtty != NULL) {
1199 // Log the precise location of the trap.
1200 for (ScopeDesc* sd = trap_scope; ; sd = sd->sender()) {
1201 xtty->begin_elem("jvms bci='%d'", sd->bci());
1202 xtty->method(sd->method());
1203 xtty->end_elem();
1204 if (sd->is_top()) break;
1205 }
1206 xtty->tail("uncommon_trap");
1207 }
1208 }
1209 // (End diagnostic printout.)
1211 // Load class if necessary
1212 if (unloaded_class_index >= 0) {
1213 constantPoolHandle constants(THREAD, trap_method->constants());
1214 load_class_by_index(constants, unloaded_class_index);
1215 }
1217 // Flush the nmethod if necessary and desirable.
1218 //
1219 // We need to avoid situations where we are re-flushing the nmethod
1220 // because of a hot deoptimization site. Repeated flushes at the same
1221 // point need to be detected by the compiler and avoided. If the compiler
1222 // cannot avoid them (or has a bug and "refuses" to avoid them), this
1223 // module must take measures to avoid an infinite cycle of recompilation
1224 // and deoptimization. There are several such measures:
1225 //
1226 // 1. If a recompilation is ordered a second time at some site X
1227 // and for the same reason R, the action is adjusted to 'reinterpret',
1228 // to give the interpreter time to exercise the method more thoroughly.
1229 // If this happens, the method's overflow_recompile_count is incremented.
1230 //
1231 // 2. If the compiler fails to reduce the deoptimization rate, then
1232 // the method's overflow_recompile_count will begin to exceed the set
1233 // limit PerBytecodeRecompilationCutoff. If this happens, the action
1234 // is adjusted to 'make_not_compilable', and the method is abandoned
1235 // to the interpreter. This is a performance hit for hot methods,
1236 // but is better than a disastrous infinite cycle of recompilations.
1237 // (Actually, only the method containing the site X is abandoned.)
1238 //
1239 // 3. In parallel with the previous measures, if the total number of
1240 // recompilations of a method exceeds the much larger set limit
1241 // PerMethodRecompilationCutoff, the method is abandoned.
1242 // This should only happen if the method is very large and has
1243 // many "lukewarm" deoptimizations. The code which enforces this
1244 // limit is elsewhere (class nmethod, class methodOopDesc).
1245 //
1246 // Note that the per-BCI 'is_recompiled' bit gives the compiler one chance
1247 // to recompile at each bytecode independently of the per-BCI cutoff.
1248 //
1249 // The decision to update code is up to the compiler, and is encoded
1250 // in the Action_xxx code. If the compiler requests Action_none
1251 // no trap state is changed, no compiled code is changed, and the
1252 // computation suffers along in the interpreter.
1253 //
1254 // The other action codes specify various tactics for decompilation
1255 // and recompilation. Action_maybe_recompile is the loosest, and
1256 // allows the compiled code to stay around until enough traps are seen,
1257 // and until the compiler gets around to recompiling the trapping method.
1258 //
1259 // The other actions cause immediate removal of the present code.
1261 bool update_trap_state = true;
1262 bool make_not_entrant = false;
1263 bool make_not_compilable = false;
1264 bool reset_counters = false;
1265 switch (action) {
1266 case Action_none:
1267 // Keep the old code.
1268 update_trap_state = false;
1269 break;
1270 case Action_maybe_recompile:
1271 // Do not need to invalidate the present code, but we can
1272 // initiate another
1273 // Start compiler without (necessarily) invalidating the nmethod.
1274 // The system will tolerate the old code, but new code should be
1275 // generated when possible.
1276 break;
1277 case Action_reinterpret:
1278 // Go back into the interpreter for a while, and then consider
1279 // recompiling form scratch.
1280 make_not_entrant = true;
1281 // Reset invocation counter for outer most method.
1282 // This will allow the interpreter to exercise the bytecodes
1283 // for a while before recompiling.
1284 // By contrast, Action_make_not_entrant is immediate.
1285 //
1286 // Note that the compiler will track null_check, null_assert,
1287 // range_check, and class_check events and log them as if they
1288 // had been traps taken from compiled code. This will update
1289 // the MDO trap history so that the next compilation will
1290 // properly detect hot trap sites.
1291 reset_counters = true;
1292 break;
1293 case Action_make_not_entrant:
1294 // Request immediate recompilation, and get rid of the old code.
1295 // Make them not entrant, so next time they are called they get
1296 // recompiled. Unloaded classes are loaded now so recompile before next
1297 // time they are called. Same for uninitialized. The interpreter will
1298 // link the missing class, if any.
1299 make_not_entrant = true;
1300 break;
1301 case Action_make_not_compilable:
1302 // Give up on compiling this method at all.
1303 make_not_entrant = true;
1304 make_not_compilable = true;
1305 break;
1306 default:
1307 ShouldNotReachHere();
1308 }
1310 // Setting +ProfileTraps fixes the following, on all platforms:
1311 // 4852688: ProfileInterpreter is off by default for ia64. The result is
1312 // infinite heroic-opt-uncommon-trap/deopt/recompile cycles, since the
1313 // recompile relies on a methodDataOop to record heroic opt failures.
1315 // Whether the interpreter is producing MDO data or not, we also need
1316 // to use the MDO to detect hot deoptimization points and control
1317 // aggressive optimization.
1318 if (ProfileTraps && update_trap_state && trap_mdo.not_null()) {
1319 assert(trap_mdo() == get_method_data(thread, trap_method, false), "sanity");
1320 uint this_trap_count = 0;
1321 bool maybe_prior_trap = false;
1322 bool maybe_prior_recompile = false;
1323 ProfileData* pdata
1324 = query_update_method_data(trap_mdo, trap_bci, reason,
1325 //outputs:
1326 this_trap_count,
1327 maybe_prior_trap,
1328 maybe_prior_recompile);
1329 // Because the interpreter also counts null, div0, range, and class
1330 // checks, these traps from compiled code are double-counted.
1331 // This is harmless; it just means that the PerXTrapLimit values
1332 // are in effect a little smaller than they look.
1334 DeoptReason per_bc_reason = reason_recorded_per_bytecode_if_any(reason);
1335 if (per_bc_reason != Reason_none) {
1336 // Now take action based on the partially known per-BCI history.
1337 if (maybe_prior_trap
1338 && this_trap_count >= (uint)PerBytecodeTrapLimit) {
1339 // If there are too many traps at this BCI, force a recompile.
1340 // This will allow the compiler to see the limit overflow, and
1341 // take corrective action, if possible. The compiler generally
1342 // does not use the exact PerBytecodeTrapLimit value, but instead
1343 // changes its tactics if it sees any traps at all. This provides
1344 // a little hysteresis, delaying a recompile until a trap happens
1345 // several times.
1346 //
1347 // Actually, since there is only one bit of counter per BCI,
1348 // the possible per-BCI counts are {0,1,(per-method count)}.
1349 // This produces accurate results if in fact there is only
1350 // one hot trap site, but begins to get fuzzy if there are
1351 // many sites. For example, if there are ten sites each
1352 // trapping two or more times, they each get the blame for
1353 // all of their traps.
1354 make_not_entrant = true;
1355 }
1357 // Detect repeated recompilation at the same BCI, and enforce a limit.
1358 if (make_not_entrant && maybe_prior_recompile) {
1359 // More than one recompile at this point.
1360 trap_mdo->inc_overflow_recompile_count();
1361 if (maybe_prior_trap
1362 && ((uint)trap_mdo->overflow_recompile_count()
1363 > (uint)PerBytecodeRecompilationCutoff)) {
1364 // Give up on the method containing the bad BCI.
1365 if (trap_method() == nm->method()) {
1366 make_not_compilable = true;
1367 } else {
1368 trap_method->set_not_compilable();
1369 // But give grace to the enclosing nm->method().
1370 }
1371 }
1372 }
1373 } else {
1374 // For reasons which are not recorded per-bytecode, we simply
1375 // force recompiles unconditionally.
1376 // (Note that PerMethodRecompilationCutoff is enforced elsewhere.)
1377 make_not_entrant = true;
1378 }
1380 // Go back to the compiler if there are too many traps in this method.
1381 if (this_trap_count >= (uint)PerMethodTrapLimit) {
1382 // If there are too many traps in this method, force a recompile.
1383 // This will allow the compiler to see the limit overflow, and
1384 // take corrective action, if possible.
1385 // (This condition is an unlikely backstop only, because the
1386 // PerBytecodeTrapLimit is more likely to take effect first,
1387 // if it is applicable.)
1388 make_not_entrant = true;
1389 }
1391 // Here's more hysteresis: If there has been a recompile at
1392 // this trap point already, run the method in the interpreter
1393 // for a while to exercise it more thoroughly.
1394 if (make_not_entrant && maybe_prior_recompile && maybe_prior_trap) {
1395 reset_counters = true;
1396 }
1398 if (make_not_entrant && pdata != NULL) {
1399 // Record the recompilation event, if any.
1400 int tstate0 = pdata->trap_state();
1401 int tstate1 = trap_state_set_recompiled(tstate0, true);
1402 if (tstate1 != tstate0)
1403 pdata->set_trap_state(tstate1);
1404 }
1405 }
1407 // Take requested actions on the method:
1409 // Reset invocation counters
1410 if (reset_counters) {
1411 if (nm->is_osr_method())
1412 reset_invocation_counter(trap_scope, CompileThreshold);
1413 else
1414 reset_invocation_counter(trap_scope);
1415 }
1417 // Recompile
1418 if (make_not_entrant) {
1419 nm->make_not_entrant();
1420 }
1422 // Give up compiling
1423 if (make_not_compilable) {
1424 assert(make_not_entrant, "consistent");
1425 nm->method()->set_not_compilable();
1426 }
1428 } // Free marked resources
1430 }
1431 JRT_END
1433 methodDataOop
1434 Deoptimization::get_method_data(JavaThread* thread, methodHandle m,
1435 bool create_if_missing) {
1436 Thread* THREAD = thread;
1437 methodDataOop mdo = m()->method_data();
1438 if (mdo == NULL && create_if_missing && !HAS_PENDING_EXCEPTION) {
1439 // Build an MDO. Ignore errors like OutOfMemory;
1440 // that simply means we won't have an MDO to update.
1441 methodOopDesc::build_interpreter_method_data(m, THREAD);
1442 if (HAS_PENDING_EXCEPTION) {
1443 assert((PENDING_EXCEPTION->is_a(SystemDictionary::OutOfMemoryError_klass())), "we expect only an OOM error here");
1444 CLEAR_PENDING_EXCEPTION;
1445 }
1446 mdo = m()->method_data();
1447 }
1448 return mdo;
1449 }
1451 ProfileData*
1452 Deoptimization::query_update_method_data(methodDataHandle trap_mdo,
1453 int trap_bci,
1454 Deoptimization::DeoptReason reason,
1455 //outputs:
1456 uint& ret_this_trap_count,
1457 bool& ret_maybe_prior_trap,
1458 bool& ret_maybe_prior_recompile) {
1459 uint prior_trap_count = trap_mdo->trap_count(reason);
1460 uint this_trap_count = trap_mdo->inc_trap_count(reason);
1462 // If the runtime cannot find a place to store trap history,
1463 // it is estimated based on the general condition of the method.
1464 // If the method has ever been recompiled, or has ever incurred
1465 // a trap with the present reason , then this BCI is assumed
1466 // (pessimistically) to be the culprit.
1467 bool maybe_prior_trap = (prior_trap_count != 0);
1468 bool maybe_prior_recompile = (trap_mdo->decompile_count() != 0);
1469 ProfileData* pdata = NULL;
1472 // For reasons which are recorded per bytecode, we check per-BCI data.
1473 DeoptReason per_bc_reason = reason_recorded_per_bytecode_if_any(reason);
1474 if (per_bc_reason != Reason_none) {
1475 // Find the profile data for this BCI. If there isn't one,
1476 // try to allocate one from the MDO's set of spares.
1477 // This will let us detect a repeated trap at this point.
1478 pdata = trap_mdo->allocate_bci_to_data(trap_bci);
1480 if (pdata != NULL) {
1481 // Query the trap state of this profile datum.
1482 int tstate0 = pdata->trap_state();
1483 if (!trap_state_has_reason(tstate0, per_bc_reason))
1484 maybe_prior_trap = false;
1485 if (!trap_state_is_recompiled(tstate0))
1486 maybe_prior_recompile = false;
1488 // Update the trap state of this profile datum.
1489 int tstate1 = tstate0;
1490 // Record the reason.
1491 tstate1 = trap_state_add_reason(tstate1, per_bc_reason);
1492 // Store the updated state on the MDO, for next time.
1493 if (tstate1 != tstate0)
1494 pdata->set_trap_state(tstate1);
1495 } else {
1496 if (LogCompilation && xtty != NULL)
1497 // Missing MDP? Leave a small complaint in the log.
1498 xtty->elem("missing_mdp bci='%d'", trap_bci);
1499 }
1500 }
1502 // Return results:
1503 ret_this_trap_count = this_trap_count;
1504 ret_maybe_prior_trap = maybe_prior_trap;
1505 ret_maybe_prior_recompile = maybe_prior_recompile;
1506 return pdata;
1507 }
1509 void
1510 Deoptimization::update_method_data_from_interpreter(methodDataHandle trap_mdo, int trap_bci, int reason) {
1511 ResourceMark rm;
1512 // Ignored outputs:
1513 uint ignore_this_trap_count;
1514 bool ignore_maybe_prior_trap;
1515 bool ignore_maybe_prior_recompile;
1516 query_update_method_data(trap_mdo, trap_bci,
1517 (DeoptReason)reason,
1518 ignore_this_trap_count,
1519 ignore_maybe_prior_trap,
1520 ignore_maybe_prior_recompile);
1521 }
1523 void Deoptimization::reset_invocation_counter(ScopeDesc* trap_scope, jint top_count) {
1524 ScopeDesc* sd = trap_scope;
1525 for (; !sd->is_top(); sd = sd->sender()) {
1526 // Reset ICs of inlined methods, since they can trigger compilations also.
1527 sd->method()->invocation_counter()->reset();
1528 }
1529 InvocationCounter* c = sd->method()->invocation_counter();
1530 if (top_count != _no_count) {
1531 // It was an OSR method, so bump the count higher.
1532 c->set(c->state(), top_count);
1533 } else {
1534 c->reset();
1535 }
1536 sd->method()->backedge_counter()->reset();
1537 }
1539 Deoptimization::UnrollBlock* Deoptimization::uncommon_trap(JavaThread* thread, jint trap_request) {
1541 // Still in Java no safepoints
1542 {
1543 // This enters VM and may safepoint
1544 uncommon_trap_inner(thread, trap_request);
1545 }
1546 return fetch_unroll_info_helper(thread);
1547 }
1549 // Local derived constants.
1550 // Further breakdown of DataLayout::trap_state, as promised by DataLayout.
1551 const int DS_REASON_MASK = DataLayout::trap_mask >> 1;
1552 const int DS_RECOMPILE_BIT = DataLayout::trap_mask - DS_REASON_MASK;
1554 //---------------------------trap_state_reason---------------------------------
1555 Deoptimization::DeoptReason
1556 Deoptimization::trap_state_reason(int trap_state) {
1557 // This assert provides the link between the width of DataLayout::trap_bits
1558 // and the encoding of "recorded" reasons. It ensures there are enough
1559 // bits to store all needed reasons in the per-BCI MDO profile.
1560 assert(DS_REASON_MASK >= Reason_RECORDED_LIMIT, "enough bits");
1561 int recompile_bit = (trap_state & DS_RECOMPILE_BIT);
1562 trap_state -= recompile_bit;
1563 if (trap_state == DS_REASON_MASK) {
1564 return Reason_many;
1565 } else {
1566 assert((int)Reason_none == 0, "state=0 => Reason_none");
1567 return (DeoptReason)trap_state;
1568 }
1569 }
1570 //-------------------------trap_state_has_reason-------------------------------
1571 int Deoptimization::trap_state_has_reason(int trap_state, int reason) {
1572 assert(reason_is_recorded_per_bytecode((DeoptReason)reason), "valid reason");
1573 assert(DS_REASON_MASK >= Reason_RECORDED_LIMIT, "enough bits");
1574 int recompile_bit = (trap_state & DS_RECOMPILE_BIT);
1575 trap_state -= recompile_bit;
1576 if (trap_state == DS_REASON_MASK) {
1577 return -1; // true, unspecifically (bottom of state lattice)
1578 } else if (trap_state == reason) {
1579 return 1; // true, definitely
1580 } else if (trap_state == 0) {
1581 return 0; // false, definitely (top of state lattice)
1582 } else {
1583 return 0; // false, definitely
1584 }
1585 }
1586 //-------------------------trap_state_add_reason-------------------------------
1587 int Deoptimization::trap_state_add_reason(int trap_state, int reason) {
1588 assert(reason_is_recorded_per_bytecode((DeoptReason)reason) || reason == Reason_many, "valid reason");
1589 int recompile_bit = (trap_state & DS_RECOMPILE_BIT);
1590 trap_state -= recompile_bit;
1591 if (trap_state == DS_REASON_MASK) {
1592 return trap_state + recompile_bit; // already at state lattice bottom
1593 } else if (trap_state == reason) {
1594 return trap_state + recompile_bit; // the condition is already true
1595 } else if (trap_state == 0) {
1596 return reason + recompile_bit; // no condition has yet been true
1597 } else {
1598 return DS_REASON_MASK + recompile_bit; // fall to state lattice bottom
1599 }
1600 }
1601 //-----------------------trap_state_is_recompiled------------------------------
1602 bool Deoptimization::trap_state_is_recompiled(int trap_state) {
1603 return (trap_state & DS_RECOMPILE_BIT) != 0;
1604 }
1605 //-----------------------trap_state_set_recompiled-----------------------------
1606 int Deoptimization::trap_state_set_recompiled(int trap_state, bool z) {
1607 if (z) return trap_state | DS_RECOMPILE_BIT;
1608 else return trap_state & ~DS_RECOMPILE_BIT;
1609 }
1610 //---------------------------format_trap_state---------------------------------
1611 // This is used for debugging and diagnostics, including hotspot.log output.
1612 const char* Deoptimization::format_trap_state(char* buf, size_t buflen,
1613 int trap_state) {
1614 DeoptReason reason = trap_state_reason(trap_state);
1615 bool recomp_flag = trap_state_is_recompiled(trap_state);
1616 // Re-encode the state from its decoded components.
1617 int decoded_state = 0;
1618 if (reason_is_recorded_per_bytecode(reason) || reason == Reason_many)
1619 decoded_state = trap_state_add_reason(decoded_state, reason);
1620 if (recomp_flag)
1621 decoded_state = trap_state_set_recompiled(decoded_state, recomp_flag);
1622 // If the state re-encodes properly, format it symbolically.
1623 // Because this routine is used for debugging and diagnostics,
1624 // be robust even if the state is a strange value.
1625 size_t len;
1626 if (decoded_state != trap_state) {
1627 // Random buggy state that doesn't decode??
1628 len = jio_snprintf(buf, buflen, "#%d", trap_state);
1629 } else {
1630 len = jio_snprintf(buf, buflen, "%s%s",
1631 trap_reason_name(reason),
1632 recomp_flag ? " recompiled" : "");
1633 }
1634 if (len >= buflen)
1635 buf[buflen-1] = '\0';
1636 return buf;
1637 }
1640 //--------------------------------statics--------------------------------------
1641 Deoptimization::DeoptAction Deoptimization::_unloaded_action
1642 = Deoptimization::Action_reinterpret;
1643 const char* Deoptimization::_trap_reason_name[Reason_LIMIT] = {
1644 // Note: Keep this in sync. with enum DeoptReason.
1645 "none",
1646 "null_check",
1647 "null_assert",
1648 "range_check",
1649 "class_check",
1650 "array_check",
1651 "intrinsic",
1652 "unloaded",
1653 "uninitialized",
1654 "unreached",
1655 "unhandled",
1656 "constraint",
1657 "div0_check",
1658 "age"
1659 };
1660 const char* Deoptimization::_trap_action_name[Action_LIMIT] = {
1661 // Note: Keep this in sync. with enum DeoptAction.
1662 "none",
1663 "maybe_recompile",
1664 "reinterpret",
1665 "make_not_entrant",
1666 "make_not_compilable"
1667 };
1669 const char* Deoptimization::trap_reason_name(int reason) {
1670 if (reason == Reason_many) return "many";
1671 if ((uint)reason < Reason_LIMIT)
1672 return _trap_reason_name[reason];
1673 static char buf[20];
1674 sprintf(buf, "reason%d", reason);
1675 return buf;
1676 }
1677 const char* Deoptimization::trap_action_name(int action) {
1678 if ((uint)action < Action_LIMIT)
1679 return _trap_action_name[action];
1680 static char buf[20];
1681 sprintf(buf, "action%d", action);
1682 return buf;
1683 }
1685 // This is used for debugging and diagnostics, including hotspot.log output.
1686 const char* Deoptimization::format_trap_request(char* buf, size_t buflen,
1687 int trap_request) {
1688 jint unloaded_class_index = trap_request_index(trap_request);
1689 const char* reason = trap_reason_name(trap_request_reason(trap_request));
1690 const char* action = trap_action_name(trap_request_action(trap_request));
1691 size_t len;
1692 if (unloaded_class_index < 0) {
1693 len = jio_snprintf(buf, buflen, "reason='%s' action='%s'",
1694 reason, action);
1695 } else {
1696 len = jio_snprintf(buf, buflen, "reason='%s' action='%s' index='%d'",
1697 reason, action, unloaded_class_index);
1698 }
1699 if (len >= buflen)
1700 buf[buflen-1] = '\0';
1701 return buf;
1702 }
1704 juint Deoptimization::_deoptimization_hist
1705 [Deoptimization::Reason_LIMIT]
1706 [1 + Deoptimization::Action_LIMIT]
1707 [Deoptimization::BC_CASE_LIMIT]
1708 = {0};
1710 enum {
1711 LSB_BITS = 8,
1712 LSB_MASK = right_n_bits(LSB_BITS)
1713 };
1715 void Deoptimization::gather_statistics(DeoptReason reason, DeoptAction action,
1716 Bytecodes::Code bc) {
1717 assert(reason >= 0 && reason < Reason_LIMIT, "oob");
1718 assert(action >= 0 && action < Action_LIMIT, "oob");
1719 _deoptimization_hist[Reason_none][0][0] += 1; // total
1720 _deoptimization_hist[reason][0][0] += 1; // per-reason total
1721 juint* cases = _deoptimization_hist[reason][1+action];
1722 juint* bc_counter_addr = NULL;
1723 juint bc_counter = 0;
1724 // Look for an unused counter, or an exact match to this BC.
1725 if (bc != Bytecodes::_illegal) {
1726 for (int bc_case = 0; bc_case < BC_CASE_LIMIT; bc_case++) {
1727 juint* counter_addr = &cases[bc_case];
1728 juint counter = *counter_addr;
1729 if ((counter == 0 && bc_counter_addr == NULL)
1730 || (Bytecodes::Code)(counter & LSB_MASK) == bc) {
1731 // this counter is either free or is already devoted to this BC
1732 bc_counter_addr = counter_addr;
1733 bc_counter = counter | bc;
1734 }
1735 }
1736 }
1737 if (bc_counter_addr == NULL) {
1738 // Overflow, or no given bytecode.
1739 bc_counter_addr = &cases[BC_CASE_LIMIT-1];
1740 bc_counter = (*bc_counter_addr & ~LSB_MASK); // clear LSB
1741 }
1742 *bc_counter_addr = bc_counter + (1 << LSB_BITS);
1743 }
1745 jint Deoptimization::total_deoptimization_count() {
1746 return _deoptimization_hist[Reason_none][0][0];
1747 }
1749 jint Deoptimization::deoptimization_count(DeoptReason reason) {
1750 assert(reason >= 0 && reason < Reason_LIMIT, "oob");
1751 return _deoptimization_hist[reason][0][0];
1752 }
1754 void Deoptimization::print_statistics() {
1755 juint total = total_deoptimization_count();
1756 juint account = total;
1757 if (total != 0) {
1758 ttyLocker ttyl;
1759 if (xtty != NULL) xtty->head("statistics type='deoptimization'");
1760 tty->print_cr("Deoptimization traps recorded:");
1761 #define PRINT_STAT_LINE(name, r) \
1762 tty->print_cr(" %4d (%4.1f%%) %s", (int)(r), ((r) * 100.0) / total, name);
1763 PRINT_STAT_LINE("total", total);
1764 // For each non-zero entry in the histogram, print the reason,
1765 // the action, and (if specifically known) the type of bytecode.
1766 for (int reason = 0; reason < Reason_LIMIT; reason++) {
1767 for (int action = 0; action < Action_LIMIT; action++) {
1768 juint* cases = _deoptimization_hist[reason][1+action];
1769 for (int bc_case = 0; bc_case < BC_CASE_LIMIT; bc_case++) {
1770 juint counter = cases[bc_case];
1771 if (counter != 0) {
1772 char name[1*K];
1773 Bytecodes::Code bc = (Bytecodes::Code)(counter & LSB_MASK);
1774 if (bc_case == BC_CASE_LIMIT && (int)bc == 0)
1775 bc = Bytecodes::_illegal;
1776 sprintf(name, "%s/%s/%s",
1777 trap_reason_name(reason),
1778 trap_action_name(action),
1779 Bytecodes::is_defined(bc)? Bytecodes::name(bc): "other");
1780 juint r = counter >> LSB_BITS;
1781 tty->print_cr(" %40s: " UINT32_FORMAT " (%.1f%%)", name, r, (r * 100.0) / total);
1782 account -= r;
1783 }
1784 }
1785 }
1786 }
1787 if (account != 0) {
1788 PRINT_STAT_LINE("unaccounted", account);
1789 }
1790 #undef PRINT_STAT_LINE
1791 if (xtty != NULL) xtty->tail("statistics");
1792 }
1793 }
1794 #else // COMPILER2
1797 // Stubs for C1 only system.
1798 bool Deoptimization::trap_state_is_recompiled(int trap_state) {
1799 return false;
1800 }
1802 const char* Deoptimization::trap_reason_name(int reason) {
1803 return "unknown";
1804 }
1806 void Deoptimization::print_statistics() {
1807 // no output
1808 }
1810 void
1811 Deoptimization::update_method_data_from_interpreter(methodDataHandle trap_mdo, int trap_bci, int reason) {
1812 // no udpate
1813 }
1815 int Deoptimization::trap_state_has_reason(int trap_state, int reason) {
1816 return 0;
1817 }
1819 void Deoptimization::gather_statistics(DeoptReason reason, DeoptAction action,
1820 Bytecodes::Code bc) {
1821 // no update
1822 }
1824 const char* Deoptimization::format_trap_state(char* buf, size_t buflen,
1825 int trap_state) {
1826 jio_snprintf(buf, buflen, "#%d", trap_state);
1827 return buf;
1828 }
1830 #endif // COMPILER2