Thu, 22 May 2014 15:52:41 -0400
8037816: Fix for 8036122 breaks build with Xcode5/clang
8043029: Change 8037816 breaks HS build with older GCC versions which don't support diagnostic pragmas
8043164: Format warning in traceStream.hpp
Summary: Backport of main fix + two corrections, enables clang compilation, turns on format attributes, corrects/mutes warnings
Reviewed-by: kvn, coleenp, iveresov, twisti
1 /*
2 * Copyright (c) 1997, 2014, 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 */
25 #include "precompiled.hpp"
26 #include "classfile/systemDictionary.hpp"
27 #include "code/debugInfoRec.hpp"
28 #include "code/nmethod.hpp"
29 #include "code/pcDesc.hpp"
30 #include "code/scopeDesc.hpp"
31 #include "interpreter/bytecode.hpp"
32 #include "interpreter/interpreter.hpp"
33 #include "interpreter/oopMapCache.hpp"
34 #include "memory/allocation.inline.hpp"
35 #include "memory/oopFactory.hpp"
36 #include "memory/resourceArea.hpp"
37 #include "oops/method.hpp"
38 #include "oops/oop.inline.hpp"
39 #include "prims/jvmtiThreadState.hpp"
40 #include "runtime/biasedLocking.hpp"
41 #include "runtime/compilationPolicy.hpp"
42 #include "runtime/deoptimization.hpp"
43 #include "runtime/interfaceSupport.hpp"
44 #include "runtime/sharedRuntime.hpp"
45 #include "runtime/signature.hpp"
46 #include "runtime/stubRoutines.hpp"
47 #include "runtime/thread.hpp"
48 #include "runtime/vframe.hpp"
49 #include "runtime/vframeArray.hpp"
50 #include "runtime/vframe_hp.hpp"
51 #include "utilities/events.hpp"
52 #include "utilities/xmlstream.hpp"
53 #ifdef TARGET_ARCH_x86
54 # include "vmreg_x86.inline.hpp"
55 #endif
56 #ifdef TARGET_ARCH_sparc
57 # include "vmreg_sparc.inline.hpp"
58 #endif
59 #ifdef TARGET_ARCH_zero
60 # include "vmreg_zero.inline.hpp"
61 #endif
62 #ifdef TARGET_ARCH_arm
63 # include "vmreg_arm.inline.hpp"
64 #endif
65 #ifdef TARGET_ARCH_ppc
66 # include "vmreg_ppc.inline.hpp"
67 #endif
68 #ifdef COMPILER2
69 #ifdef TARGET_ARCH_MODEL_x86_32
70 # include "adfiles/ad_x86_32.hpp"
71 #endif
72 #ifdef TARGET_ARCH_MODEL_x86_64
73 # include "adfiles/ad_x86_64.hpp"
74 #endif
75 #ifdef TARGET_ARCH_MODEL_sparc
76 # include "adfiles/ad_sparc.hpp"
77 #endif
78 #ifdef TARGET_ARCH_MODEL_zero
79 # include "adfiles/ad_zero.hpp"
80 #endif
81 #ifdef TARGET_ARCH_MODEL_arm
82 # include "adfiles/ad_arm.hpp"
83 #endif
84 #ifdef TARGET_ARCH_MODEL_ppc_32
85 # include "adfiles/ad_ppc_32.hpp"
86 #endif
87 #ifdef TARGET_ARCH_MODEL_ppc_64
88 # include "adfiles/ad_ppc_64.hpp"
89 #endif
90 #endif // COMPILER2
92 PRAGMA_FORMAT_MUTE_WARNINGS_FOR_GCC
94 bool DeoptimizationMarker::_is_active = false;
96 Deoptimization::UnrollBlock::UnrollBlock(int size_of_deoptimized_frame,
97 int caller_adjustment,
98 int caller_actual_parameters,
99 int number_of_frames,
100 intptr_t* frame_sizes,
101 address* frame_pcs,
102 BasicType return_type) {
103 _size_of_deoptimized_frame = size_of_deoptimized_frame;
104 _caller_adjustment = caller_adjustment;
105 _caller_actual_parameters = caller_actual_parameters;
106 _number_of_frames = number_of_frames;
107 _frame_sizes = frame_sizes;
108 _frame_pcs = frame_pcs;
109 _register_block = NEW_C_HEAP_ARRAY(intptr_t, RegisterMap::reg_count * 2, mtCompiler);
110 _return_type = return_type;
111 _initial_info = 0;
112 // PD (x86 only)
113 _counter_temp = 0;
114 _unpack_kind = 0;
115 _sender_sp_temp = 0;
117 _total_frame_sizes = size_of_frames();
118 }
121 Deoptimization::UnrollBlock::~UnrollBlock() {
122 FREE_C_HEAP_ARRAY(intptr_t, _frame_sizes, mtCompiler);
123 FREE_C_HEAP_ARRAY(intptr_t, _frame_pcs, mtCompiler);
124 FREE_C_HEAP_ARRAY(intptr_t, _register_block, mtCompiler);
125 }
128 intptr_t* Deoptimization::UnrollBlock::value_addr_at(int register_number) const {
129 assert(register_number < RegisterMap::reg_count, "checking register number");
130 return &_register_block[register_number * 2];
131 }
135 int Deoptimization::UnrollBlock::size_of_frames() const {
136 // Acount first for the adjustment of the initial frame
137 int result = _caller_adjustment;
138 for (int index = 0; index < number_of_frames(); index++) {
139 result += frame_sizes()[index];
140 }
141 return result;
142 }
145 void Deoptimization::UnrollBlock::print() {
146 ttyLocker ttyl;
147 tty->print_cr("UnrollBlock");
148 tty->print_cr(" size_of_deoptimized_frame = %d", _size_of_deoptimized_frame);
149 tty->print( " frame_sizes: ");
150 for (int index = 0; index < number_of_frames(); index++) {
151 tty->print("%d ", frame_sizes()[index]);
152 }
153 tty->cr();
154 }
157 // In order to make fetch_unroll_info work properly with escape
158 // analysis, The method was changed from JRT_LEAF to JRT_BLOCK_ENTRY and
159 // ResetNoHandleMark and HandleMark were removed from it. The actual reallocation
160 // of previously eliminated objects occurs in realloc_objects, which is
161 // called from the method fetch_unroll_info_helper below.
162 JRT_BLOCK_ENTRY(Deoptimization::UnrollBlock*, Deoptimization::fetch_unroll_info(JavaThread* thread))
163 // It is actually ok to allocate handles in a leaf method. It causes no safepoints,
164 // but makes the entry a little slower. There is however a little dance we have to
165 // do in debug mode to get around the NoHandleMark code in the JRT_LEAF macro
167 // fetch_unroll_info() is called at the beginning of the deoptimization
168 // handler. Note this fact before we start generating temporary frames
169 // that can confuse an asynchronous stack walker. This counter is
170 // decremented at the end of unpack_frames().
171 thread->inc_in_deopt_handler();
173 return fetch_unroll_info_helper(thread);
174 JRT_END
177 // This is factored, since it is both called from a JRT_LEAF (deoptimization) and a JRT_ENTRY (uncommon_trap)
178 Deoptimization::UnrollBlock* Deoptimization::fetch_unroll_info_helper(JavaThread* thread) {
180 // Note: there is a safepoint safety issue here. No matter whether we enter
181 // via vanilla deopt or uncommon trap we MUST NOT stop at a safepoint once
182 // the vframeArray is created.
183 //
185 // Allocate our special deoptimization ResourceMark
186 DeoptResourceMark* dmark = new DeoptResourceMark(thread);
187 assert(thread->deopt_mark() == NULL, "Pending deopt!");
188 thread->set_deopt_mark(dmark);
190 frame stub_frame = thread->last_frame(); // Makes stack walkable as side effect
191 RegisterMap map(thread, true);
192 RegisterMap dummy_map(thread, false);
193 // Now get the deoptee with a valid map
194 frame deoptee = stub_frame.sender(&map);
195 // Set the deoptee nmethod
196 assert(thread->deopt_nmethod() == NULL, "Pending deopt!");
197 thread->set_deopt_nmethod(deoptee.cb()->as_nmethod_or_null());
199 if (VerifyStack) {
200 thread->validate_frame_layout();
201 }
203 // Create a growable array of VFrames where each VFrame represents an inlined
204 // Java frame. This storage is allocated with the usual system arena.
205 assert(deoptee.is_compiled_frame(), "Wrong frame type");
206 GrowableArray<compiledVFrame*>* chunk = new GrowableArray<compiledVFrame*>(10);
207 vframe* vf = vframe::new_vframe(&deoptee, &map, thread);
208 while (!vf->is_top()) {
209 assert(vf->is_compiled_frame(), "Wrong frame type");
210 chunk->push(compiledVFrame::cast(vf));
211 vf = vf->sender();
212 }
213 assert(vf->is_compiled_frame(), "Wrong frame type");
214 chunk->push(compiledVFrame::cast(vf));
216 #ifdef COMPILER2
217 // Reallocate the non-escaping objects and restore their fields. Then
218 // relock objects if synchronization on them was eliminated.
219 if (DoEscapeAnalysis || EliminateNestedLocks) {
220 if (EliminateAllocations) {
221 assert (chunk->at(0)->scope() != NULL,"expect only compiled java frames");
222 GrowableArray<ScopeValue*>* objects = chunk->at(0)->scope()->objects();
224 // The flag return_oop() indicates call sites which return oop
225 // in compiled code. Such sites include java method calls,
226 // runtime calls (for example, used to allocate new objects/arrays
227 // on slow code path) and any other calls generated in compiled code.
228 // It is not guaranteed that we can get such information here only
229 // by analyzing bytecode in deoptimized frames. This is why this flag
230 // is set during method compilation (see Compile::Process_OopMap_Node()).
231 bool save_oop_result = chunk->at(0)->scope()->return_oop();
232 Handle return_value;
233 if (save_oop_result) {
234 // Reallocation may trigger GC. If deoptimization happened on return from
235 // call which returns oop we need to save it since it is not in oopmap.
236 oop result = deoptee.saved_oop_result(&map);
237 assert(result == NULL || result->is_oop(), "must be oop");
238 return_value = Handle(thread, result);
239 assert(Universe::heap()->is_in_or_null(result), "must be heap pointer");
240 if (TraceDeoptimization) {
241 ttyLocker ttyl;
242 tty->print_cr("SAVED OOP RESULT " INTPTR_FORMAT " in thread " INTPTR_FORMAT, (void *)result, thread);
243 }
244 }
245 bool reallocated = false;
246 if (objects != NULL) {
247 JRT_BLOCK
248 reallocated = realloc_objects(thread, &deoptee, objects, THREAD);
249 JRT_END
250 }
251 if (reallocated) {
252 reassign_fields(&deoptee, &map, objects);
253 #ifndef PRODUCT
254 if (TraceDeoptimization) {
255 ttyLocker ttyl;
256 tty->print_cr("REALLOC OBJECTS in thread " INTPTR_FORMAT, thread);
257 print_objects(objects);
258 }
259 #endif
260 }
261 if (save_oop_result) {
262 // Restore result.
263 deoptee.set_saved_oop_result(&map, return_value());
264 }
265 }
266 if (EliminateLocks) {
267 #ifndef PRODUCT
268 bool first = true;
269 #endif
270 for (int i = 0; i < chunk->length(); i++) {
271 compiledVFrame* cvf = chunk->at(i);
272 assert (cvf->scope() != NULL,"expect only compiled java frames");
273 GrowableArray<MonitorInfo*>* monitors = cvf->monitors();
274 if (monitors->is_nonempty()) {
275 relock_objects(monitors, thread);
276 #ifndef PRODUCT
277 if (TraceDeoptimization) {
278 ttyLocker ttyl;
279 for (int j = 0; j < monitors->length(); j++) {
280 MonitorInfo* mi = monitors->at(j);
281 if (mi->eliminated()) {
282 if (first) {
283 first = false;
284 tty->print_cr("RELOCK OBJECTS in thread " INTPTR_FORMAT, thread);
285 }
286 tty->print_cr(" object <" INTPTR_FORMAT "> locked", (void *)mi->owner());
287 }
288 }
289 }
290 #endif
291 }
292 }
293 }
294 }
295 #endif // COMPILER2
296 // Ensure that no safepoint is taken after pointers have been stored
297 // in fields of rematerialized objects. If a safepoint occurs from here on
298 // out the java state residing in the vframeArray will be missed.
299 No_Safepoint_Verifier no_safepoint;
301 vframeArray* array = create_vframeArray(thread, deoptee, &map, chunk);
303 assert(thread->vframe_array_head() == NULL, "Pending deopt!");;
304 thread->set_vframe_array_head(array);
306 // Now that the vframeArray has been created if we have any deferred local writes
307 // added by jvmti then we can free up that structure as the data is now in the
308 // vframeArray
310 if (thread->deferred_locals() != NULL) {
311 GrowableArray<jvmtiDeferredLocalVariableSet*>* list = thread->deferred_locals();
312 int i = 0;
313 do {
314 // Because of inlining we could have multiple vframes for a single frame
315 // and several of the vframes could have deferred writes. Find them all.
316 if (list->at(i)->id() == array->original().id()) {
317 jvmtiDeferredLocalVariableSet* dlv = list->at(i);
318 list->remove_at(i);
319 // individual jvmtiDeferredLocalVariableSet are CHeapObj's
320 delete dlv;
321 } else {
322 i++;
323 }
324 } while ( i < list->length() );
325 if (list->length() == 0) {
326 thread->set_deferred_locals(NULL);
327 // free the list and elements back to C heap.
328 delete list;
329 }
331 }
333 #ifndef SHARK
334 // Compute the caller frame based on the sender sp of stub_frame and stored frame sizes info.
335 CodeBlob* cb = stub_frame.cb();
336 // Verify we have the right vframeArray
337 assert(cb->frame_size() >= 0, "Unexpected frame size");
338 intptr_t* unpack_sp = stub_frame.sp() + cb->frame_size();
340 // If the deopt call site is a MethodHandle invoke call site we have
341 // to adjust the unpack_sp.
342 nmethod* deoptee_nm = deoptee.cb()->as_nmethod_or_null();
343 if (deoptee_nm != NULL && deoptee_nm->is_method_handle_return(deoptee.pc()))
344 unpack_sp = deoptee.unextended_sp();
346 #ifdef ASSERT
347 assert(cb->is_deoptimization_stub() || cb->is_uncommon_trap_stub(), "just checking");
348 #endif
349 #else
350 intptr_t* unpack_sp = stub_frame.sender(&dummy_map).unextended_sp();
351 #endif // !SHARK
353 // This is a guarantee instead of an assert because if vframe doesn't match
354 // we will unpack the wrong deoptimized frame and wind up in strange places
355 // where it will be very difficult to figure out what went wrong. Better
356 // to die an early death here than some very obscure death later when the
357 // trail is cold.
358 // Note: on ia64 this guarantee can be fooled by frames with no memory stack
359 // in that it will fail to detect a problem when there is one. This needs
360 // more work in tiger timeframe.
361 guarantee(array->unextended_sp() == unpack_sp, "vframe_array_head must contain the vframeArray to unpack");
363 int number_of_frames = array->frames();
365 // Compute the vframes' sizes. Note that frame_sizes[] entries are ordered from outermost to innermost
366 // virtual activation, which is the reverse of the elements in the vframes array.
367 intptr_t* frame_sizes = NEW_C_HEAP_ARRAY(intptr_t, number_of_frames, mtCompiler);
368 // +1 because we always have an interpreter return address for the final slot.
369 address* frame_pcs = NEW_C_HEAP_ARRAY(address, number_of_frames + 1, mtCompiler);
370 int popframe_extra_args = 0;
371 // Create an interpreter return address for the stub to use as its return
372 // address so the skeletal frames are perfectly walkable
373 frame_pcs[number_of_frames] = Interpreter::deopt_entry(vtos, 0);
375 // PopFrame requires that the preserved incoming arguments from the recently-popped topmost
376 // activation be put back on the expression stack of the caller for reexecution
377 if (JvmtiExport::can_pop_frame() && thread->popframe_forcing_deopt_reexecution()) {
378 popframe_extra_args = in_words(thread->popframe_preserved_args_size_in_words());
379 }
381 // Find the current pc for sender of the deoptee. Since the sender may have been deoptimized
382 // itself since the deoptee vframeArray was created we must get a fresh value of the pc rather
383 // than simply use array->sender.pc(). This requires us to walk the current set of frames
384 //
385 frame deopt_sender = stub_frame.sender(&dummy_map); // First is the deoptee frame
386 deopt_sender = deopt_sender.sender(&dummy_map); // Now deoptee caller
388 // It's possible that the number of paramters at the call site is
389 // different than number of arguments in the callee when method
390 // handles are used. If the caller is interpreted get the real
391 // value so that the proper amount of space can be added to it's
392 // frame.
393 bool caller_was_method_handle = false;
394 if (deopt_sender.is_interpreted_frame()) {
395 methodHandle method = deopt_sender.interpreter_frame_method();
396 Bytecode_invoke cur = Bytecode_invoke_check(method, deopt_sender.interpreter_frame_bci());
397 if (cur.is_invokedynamic() || cur.is_invokehandle()) {
398 // Method handle invokes may involve fairly arbitrary chains of
399 // calls so it's impossible to know how much actual space the
400 // caller has for locals.
401 caller_was_method_handle = true;
402 }
403 }
405 //
406 // frame_sizes/frame_pcs[0] oldest frame (int or c2i)
407 // frame_sizes/frame_pcs[1] next oldest frame (int)
408 // frame_sizes/frame_pcs[n] youngest frame (int)
409 //
410 // Now a pc in frame_pcs is actually the return address to the frame's caller (a frame
411 // owns the space for the return address to it's caller). Confusing ain't it.
412 //
413 // The vframe array can address vframes with indices running from
414 // 0.._frames-1. Index 0 is the youngest frame and _frame - 1 is the oldest (root) frame.
415 // When we create the skeletal frames we need the oldest frame to be in the zero slot
416 // in the frame_sizes/frame_pcs so the assembly code can do a trivial walk.
417 // so things look a little strange in this loop.
418 //
419 int callee_parameters = 0;
420 int callee_locals = 0;
421 for (int index = 0; index < array->frames(); index++ ) {
422 // frame[number_of_frames - 1 ] = on_stack_size(youngest)
423 // frame[number_of_frames - 2 ] = on_stack_size(sender(youngest))
424 // frame[number_of_frames - 3 ] = on_stack_size(sender(sender(youngest)))
425 int caller_parms = callee_parameters;
426 if ((index == array->frames() - 1) && caller_was_method_handle) {
427 caller_parms = 0;
428 }
429 frame_sizes[number_of_frames - 1 - index] = BytesPerWord * array->element(index)->on_stack_size(caller_parms,
430 callee_parameters,
431 callee_locals,
432 index == 0,
433 index == array->frames() - 1,
434 popframe_extra_args);
435 // This pc doesn't have to be perfect just good enough to identify the frame
436 // as interpreted so the skeleton frame will be walkable
437 // The correct pc will be set when the skeleton frame is completely filled out
438 // The final pc we store in the loop is wrong and will be overwritten below
439 frame_pcs[number_of_frames - 1 - index ] = Interpreter::deopt_entry(vtos, 0) - frame::pc_return_offset;
441 callee_parameters = array->element(index)->method()->size_of_parameters();
442 callee_locals = array->element(index)->method()->max_locals();
443 popframe_extra_args = 0;
444 }
446 // Compute whether the root vframe returns a float or double value.
447 BasicType return_type;
448 {
449 HandleMark hm;
450 methodHandle method(thread, array->element(0)->method());
451 Bytecode_invoke invoke = Bytecode_invoke_check(method, array->element(0)->bci());
452 return_type = invoke.is_valid() ? invoke.result_type() : T_ILLEGAL;
453 }
455 // Compute information for handling adapters and adjusting the frame size of the caller.
456 int caller_adjustment = 0;
458 // Compute the amount the oldest interpreter frame will have to adjust
459 // its caller's stack by. If the caller is a compiled frame then
460 // we pretend that the callee has no parameters so that the
461 // extension counts for the full amount of locals and not just
462 // locals-parms. This is because without a c2i adapter the parm
463 // area as created by the compiled frame will not be usable by
464 // the interpreter. (Depending on the calling convention there
465 // may not even be enough space).
467 // QQQ I'd rather see this pushed down into last_frame_adjust
468 // and have it take the sender (aka caller).
470 if (deopt_sender.is_compiled_frame() || caller_was_method_handle) {
471 caller_adjustment = last_frame_adjust(0, callee_locals);
472 } else if (callee_locals > callee_parameters) {
473 // The caller frame may need extending to accommodate
474 // non-parameter locals of the first unpacked interpreted frame.
475 // Compute that adjustment.
476 caller_adjustment = last_frame_adjust(callee_parameters, callee_locals);
477 }
479 // If the sender is deoptimized the we must retrieve the address of the handler
480 // since the frame will "magically" show the original pc before the deopt
481 // and we'd undo the deopt.
483 frame_pcs[0] = deopt_sender.raw_pc();
485 #ifndef SHARK
486 assert(CodeCache::find_blob_unsafe(frame_pcs[0]) != NULL, "bad pc");
487 #endif // SHARK
489 UnrollBlock* info = new UnrollBlock(array->frame_size() * BytesPerWord,
490 caller_adjustment * BytesPerWord,
491 caller_was_method_handle ? 0 : callee_parameters,
492 number_of_frames,
493 frame_sizes,
494 frame_pcs,
495 return_type);
496 // On some platforms, we need a way to pass some platform dependent
497 // information to the unpacking code so the skeletal frames come out
498 // correct (initial fp value, unextended sp, ...)
499 info->set_initial_info((intptr_t) array->sender().initial_deoptimization_info());
501 if (array->frames() > 1) {
502 if (VerifyStack && TraceDeoptimization) {
503 ttyLocker ttyl;
504 tty->print_cr("Deoptimizing method containing inlining");
505 }
506 }
508 array->set_unroll_block(info);
509 return info;
510 }
512 // Called to cleanup deoptimization data structures in normal case
513 // after unpacking to stack and when stack overflow error occurs
514 void Deoptimization::cleanup_deopt_info(JavaThread *thread,
515 vframeArray *array) {
517 // Get array if coming from exception
518 if (array == NULL) {
519 array = thread->vframe_array_head();
520 }
521 thread->set_vframe_array_head(NULL);
523 // Free the previous UnrollBlock
524 vframeArray* old_array = thread->vframe_array_last();
525 thread->set_vframe_array_last(array);
527 if (old_array != NULL) {
528 UnrollBlock* old_info = old_array->unroll_block();
529 old_array->set_unroll_block(NULL);
530 delete old_info;
531 delete old_array;
532 }
534 // Deallocate any resource creating in this routine and any ResourceObjs allocated
535 // inside the vframeArray (StackValueCollections)
537 delete thread->deopt_mark();
538 thread->set_deopt_mark(NULL);
539 thread->set_deopt_nmethod(NULL);
542 if (JvmtiExport::can_pop_frame()) {
543 #ifndef CC_INTERP
544 // Regardless of whether we entered this routine with the pending
545 // popframe condition bit set, we should always clear it now
546 thread->clear_popframe_condition();
547 #else
548 // C++ interpeter will clear has_pending_popframe when it enters
549 // with method_resume. For deopt_resume2 we clear it now.
550 if (thread->popframe_forcing_deopt_reexecution())
551 thread->clear_popframe_condition();
552 #endif /* CC_INTERP */
553 }
555 // unpack_frames() is called at the end of the deoptimization handler
556 // and (in C2) at the end of the uncommon trap handler. Note this fact
557 // so that an asynchronous stack walker can work again. This counter is
558 // incremented at the beginning of fetch_unroll_info() and (in C2) at
559 // the beginning of uncommon_trap().
560 thread->dec_in_deopt_handler();
561 }
564 // Return BasicType of value being returned
565 JRT_LEAF(BasicType, Deoptimization::unpack_frames(JavaThread* thread, int exec_mode))
567 // We are already active int he special DeoptResourceMark any ResourceObj's we
568 // allocate will be freed at the end of the routine.
570 // It is actually ok to allocate handles in a leaf method. It causes no safepoints,
571 // but makes the entry a little slower. There is however a little dance we have to
572 // do in debug mode to get around the NoHandleMark code in the JRT_LEAF macro
573 ResetNoHandleMark rnhm; // No-op in release/product versions
574 HandleMark hm;
576 frame stub_frame = thread->last_frame();
578 // Since the frame to unpack is the top frame of this thread, the vframe_array_head
579 // must point to the vframeArray for the unpack frame.
580 vframeArray* array = thread->vframe_array_head();
582 #ifndef PRODUCT
583 if (TraceDeoptimization) {
584 ttyLocker ttyl;
585 tty->print_cr("DEOPT UNPACKING thread " INTPTR_FORMAT " vframeArray " INTPTR_FORMAT " mode %d", thread, array, exec_mode);
586 }
587 #endif
588 Events::log(thread, "DEOPT UNPACKING pc=" INTPTR_FORMAT " sp=" INTPTR_FORMAT " mode %d",
589 stub_frame.pc(), stub_frame.sp(), exec_mode);
591 UnrollBlock* info = array->unroll_block();
593 // Unpack the interpreter frames and any adapter frame (c2 only) we might create.
594 array->unpack_to_stack(stub_frame, exec_mode, info->caller_actual_parameters());
596 BasicType bt = info->return_type();
598 // If we have an exception pending, claim that the return type is an oop
599 // so the deopt_blob does not overwrite the exception_oop.
601 if (exec_mode == Unpack_exception)
602 bt = T_OBJECT;
604 // Cleanup thread deopt data
605 cleanup_deopt_info(thread, array);
607 #ifndef PRODUCT
608 if (VerifyStack) {
609 ResourceMark res_mark;
611 thread->validate_frame_layout();
613 // Verify that the just-unpacked frames match the interpreter's
614 // notions of expression stack and locals
615 vframeArray* cur_array = thread->vframe_array_last();
616 RegisterMap rm(thread, false);
617 rm.set_include_argument_oops(false);
618 bool is_top_frame = true;
619 int callee_size_of_parameters = 0;
620 int callee_max_locals = 0;
621 for (int i = 0; i < cur_array->frames(); i++) {
622 vframeArrayElement* el = cur_array->element(i);
623 frame* iframe = el->iframe();
624 guarantee(iframe->is_interpreted_frame(), "Wrong frame type");
626 // Get the oop map for this bci
627 InterpreterOopMap mask;
628 int cur_invoke_parameter_size = 0;
629 bool try_next_mask = false;
630 int next_mask_expression_stack_size = -1;
631 int top_frame_expression_stack_adjustment = 0;
632 methodHandle mh(thread, iframe->interpreter_frame_method());
633 OopMapCache::compute_one_oop_map(mh, iframe->interpreter_frame_bci(), &mask);
634 BytecodeStream str(mh);
635 str.set_start(iframe->interpreter_frame_bci());
636 int max_bci = mh->code_size();
637 // Get to the next bytecode if possible
638 assert(str.bci() < max_bci, "bci in interpreter frame out of bounds");
639 // Check to see if we can grab the number of outgoing arguments
640 // at an uncommon trap for an invoke (where the compiler
641 // generates debug info before the invoke has executed)
642 Bytecodes::Code cur_code = str.next();
643 if (cur_code == Bytecodes::_invokevirtual ||
644 cur_code == Bytecodes::_invokespecial ||
645 cur_code == Bytecodes::_invokestatic ||
646 cur_code == Bytecodes::_invokeinterface ||
647 cur_code == Bytecodes::_invokedynamic) {
648 Bytecode_invoke invoke(mh, iframe->interpreter_frame_bci());
649 Symbol* signature = invoke.signature();
650 ArgumentSizeComputer asc(signature);
651 cur_invoke_parameter_size = asc.size();
652 if (invoke.has_receiver()) {
653 // Add in receiver
654 ++cur_invoke_parameter_size;
655 }
656 if (i != 0 && !invoke.is_invokedynamic() && MethodHandles::has_member_arg(invoke.klass(), invoke.name())) {
657 callee_size_of_parameters++;
658 }
659 }
660 if (str.bci() < max_bci) {
661 Bytecodes::Code bc = str.next();
662 if (bc >= 0) {
663 // The interpreter oop map generator reports results before
664 // the current bytecode has executed except in the case of
665 // calls. It seems to be hard to tell whether the compiler
666 // has emitted debug information matching the "state before"
667 // a given bytecode or the state after, so we try both
668 switch (cur_code) {
669 case Bytecodes::_invokevirtual:
670 case Bytecodes::_invokespecial:
671 case Bytecodes::_invokestatic:
672 case Bytecodes::_invokeinterface:
673 case Bytecodes::_invokedynamic:
674 case Bytecodes::_athrow:
675 break;
676 default: {
677 InterpreterOopMap next_mask;
678 OopMapCache::compute_one_oop_map(mh, str.bci(), &next_mask);
679 next_mask_expression_stack_size = next_mask.expression_stack_size();
680 // Need to subtract off the size of the result type of
681 // the bytecode because this is not described in the
682 // debug info but returned to the interpreter in the TOS
683 // caching register
684 BasicType bytecode_result_type = Bytecodes::result_type(cur_code);
685 if (bytecode_result_type != T_ILLEGAL) {
686 top_frame_expression_stack_adjustment = type2size[bytecode_result_type];
687 }
688 assert(top_frame_expression_stack_adjustment >= 0, "");
689 try_next_mask = true;
690 break;
691 }
692 }
693 }
694 }
696 // Verify stack depth and oops in frame
697 // This assertion may be dependent on the platform we're running on and may need modification (tested on x86 and sparc)
698 if (!(
699 /* SPARC */
700 (iframe->interpreter_frame_expression_stack_size() == mask.expression_stack_size() + callee_size_of_parameters) ||
701 /* x86 */
702 (iframe->interpreter_frame_expression_stack_size() == mask.expression_stack_size() + callee_max_locals) ||
703 (try_next_mask &&
704 (iframe->interpreter_frame_expression_stack_size() == (next_mask_expression_stack_size -
705 top_frame_expression_stack_adjustment))) ||
706 (is_top_frame && (exec_mode == Unpack_exception) && iframe->interpreter_frame_expression_stack_size() == 0) ||
707 (is_top_frame && (exec_mode == Unpack_uncommon_trap || exec_mode == Unpack_reexecute) &&
708 (iframe->interpreter_frame_expression_stack_size() == mask.expression_stack_size() + cur_invoke_parameter_size))
709 )) {
710 ttyLocker ttyl;
712 // Print out some information that will help us debug the problem
713 tty->print_cr("Wrong number of expression stack elements during deoptimization");
714 tty->print_cr(" Error occurred while verifying frame %d (0..%d, 0 is topmost)", i, cur_array->frames() - 1);
715 tty->print_cr(" Fabricated interpreter frame had %d expression stack elements",
716 iframe->interpreter_frame_expression_stack_size());
717 tty->print_cr(" Interpreter oop map had %d expression stack elements", mask.expression_stack_size());
718 tty->print_cr(" try_next_mask = %d", try_next_mask);
719 tty->print_cr(" next_mask_expression_stack_size = %d", next_mask_expression_stack_size);
720 tty->print_cr(" callee_size_of_parameters = %d", callee_size_of_parameters);
721 tty->print_cr(" callee_max_locals = %d", callee_max_locals);
722 tty->print_cr(" top_frame_expression_stack_adjustment = %d", top_frame_expression_stack_adjustment);
723 tty->print_cr(" exec_mode = %d", exec_mode);
724 tty->print_cr(" cur_invoke_parameter_size = %d", cur_invoke_parameter_size);
725 tty->print_cr(" Thread = " INTPTR_FORMAT ", thread ID = " UINTX_FORMAT, thread, thread->osthread()->thread_id());
726 tty->print_cr(" Interpreted frames:");
727 for (int k = 0; k < cur_array->frames(); k++) {
728 vframeArrayElement* el = cur_array->element(k);
729 tty->print_cr(" %s (bci %d)", el->method()->name_and_sig_as_C_string(), el->bci());
730 }
731 cur_array->print_on_2(tty);
732 guarantee(false, "wrong number of expression stack elements during deopt");
733 }
734 VerifyOopClosure verify;
735 iframe->oops_interpreted_do(&verify, NULL, &rm, false);
736 callee_size_of_parameters = mh->size_of_parameters();
737 callee_max_locals = mh->max_locals();
738 is_top_frame = false;
739 }
740 }
741 #endif /* !PRODUCT */
744 return bt;
745 JRT_END
748 int Deoptimization::deoptimize_dependents() {
749 Threads::deoptimized_wrt_marked_nmethods();
750 return 0;
751 }
754 #ifdef COMPILER2
755 bool Deoptimization::realloc_objects(JavaThread* thread, frame* fr, GrowableArray<ScopeValue*>* objects, TRAPS) {
756 Handle pending_exception(thread->pending_exception());
757 const char* exception_file = thread->exception_file();
758 int exception_line = thread->exception_line();
759 thread->clear_pending_exception();
761 for (int i = 0; i < objects->length(); i++) {
762 assert(objects->at(i)->is_object(), "invalid debug information");
763 ObjectValue* sv = (ObjectValue*) objects->at(i);
765 KlassHandle k(java_lang_Class::as_Klass(sv->klass()->as_ConstantOopReadValue()->value()()));
766 oop obj = NULL;
768 if (k->oop_is_instance()) {
769 InstanceKlass* ik = InstanceKlass::cast(k());
770 obj = ik->allocate_instance(CHECK_(false));
771 } else if (k->oop_is_typeArray()) {
772 TypeArrayKlass* ak = TypeArrayKlass::cast(k());
773 assert(sv->field_size() % type2size[ak->element_type()] == 0, "non-integral array length");
774 int len = sv->field_size() / type2size[ak->element_type()];
775 obj = ak->allocate(len, CHECK_(false));
776 } else if (k->oop_is_objArray()) {
777 ObjArrayKlass* ak = ObjArrayKlass::cast(k());
778 obj = ak->allocate(sv->field_size(), CHECK_(false));
779 }
781 assert(obj != NULL, "allocation failed");
782 assert(sv->value().is_null(), "redundant reallocation");
783 sv->set_value(obj);
784 }
786 if (pending_exception.not_null()) {
787 thread->set_pending_exception(pending_exception(), exception_file, exception_line);
788 }
790 return true;
791 }
793 // This assumes that the fields are stored in ObjectValue in the same order
794 // they are yielded by do_nonstatic_fields.
795 class FieldReassigner: public FieldClosure {
796 frame* _fr;
797 RegisterMap* _reg_map;
798 ObjectValue* _sv;
799 InstanceKlass* _ik;
800 oop _obj;
802 int _i;
803 public:
804 FieldReassigner(frame* fr, RegisterMap* reg_map, ObjectValue* sv, oop obj) :
805 _fr(fr), _reg_map(reg_map), _sv(sv), _obj(obj), _i(0) {}
807 int i() const { return _i; }
810 void do_field(fieldDescriptor* fd) {
811 intptr_t val;
812 StackValue* value =
813 StackValue::create_stack_value(_fr, _reg_map, _sv->field_at(i()));
814 int offset = fd->offset();
815 switch (fd->field_type()) {
816 case T_OBJECT: case T_ARRAY:
817 assert(value->type() == T_OBJECT, "Agreement.");
818 _obj->obj_field_put(offset, value->get_obj()());
819 break;
821 case T_LONG: case T_DOUBLE: {
822 assert(value->type() == T_INT, "Agreement.");
823 StackValue* low =
824 StackValue::create_stack_value(_fr, _reg_map, _sv->field_at(++_i));
825 #ifdef _LP64
826 jlong res = (jlong)low->get_int();
827 #else
828 #ifdef SPARC
829 // For SPARC we have to swap high and low words.
830 jlong res = jlong_from((jint)low->get_int(), (jint)value->get_int());
831 #else
832 jlong res = jlong_from((jint)value->get_int(), (jint)low->get_int());
833 #endif //SPARC
834 #endif
835 _obj->long_field_put(offset, res);
836 break;
837 }
838 // Have to cast to INT (32 bits) pointer to avoid little/big-endian problem.
839 case T_INT: case T_FLOAT: // 4 bytes.
840 assert(value->type() == T_INT, "Agreement.");
841 val = value->get_int();
842 _obj->int_field_put(offset, (jint)*((jint*)&val));
843 break;
845 case T_SHORT: case T_CHAR: // 2 bytes
846 assert(value->type() == T_INT, "Agreement.");
847 val = value->get_int();
848 _obj->short_field_put(offset, (jshort)*((jint*)&val));
849 break;
851 case T_BOOLEAN: case T_BYTE: // 1 byte
852 assert(value->type() == T_INT, "Agreement.");
853 val = value->get_int();
854 _obj->bool_field_put(offset, (jboolean)*((jint*)&val));
855 break;
857 default:
858 ShouldNotReachHere();
859 }
860 _i++;
861 }
862 };
864 // restore elements of an eliminated type array
865 void Deoptimization::reassign_type_array_elements(frame* fr, RegisterMap* reg_map, ObjectValue* sv, typeArrayOop obj, BasicType type) {
866 int index = 0;
867 intptr_t val;
869 for (int i = 0; i < sv->field_size(); i++) {
870 StackValue* value = StackValue::create_stack_value(fr, reg_map, sv->field_at(i));
871 switch(type) {
872 case T_LONG: case T_DOUBLE: {
873 assert(value->type() == T_INT, "Agreement.");
874 StackValue* low =
875 StackValue::create_stack_value(fr, reg_map, sv->field_at(++i));
876 #ifdef _LP64
877 jlong res = (jlong)low->get_int();
878 #else
879 #ifdef SPARC
880 // For SPARC we have to swap high and low words.
881 jlong res = jlong_from((jint)low->get_int(), (jint)value->get_int());
882 #else
883 jlong res = jlong_from((jint)value->get_int(), (jint)low->get_int());
884 #endif //SPARC
885 #endif
886 obj->long_at_put(index, res);
887 break;
888 }
890 // Have to cast to INT (32 bits) pointer to avoid little/big-endian problem.
891 case T_INT: case T_FLOAT: // 4 bytes.
892 assert(value->type() == T_INT, "Agreement.");
893 val = value->get_int();
894 obj->int_at_put(index, (jint)*((jint*)&val));
895 break;
897 case T_SHORT: case T_CHAR: // 2 bytes
898 assert(value->type() == T_INT, "Agreement.");
899 val = value->get_int();
900 obj->short_at_put(index, (jshort)*((jint*)&val));
901 break;
903 case T_BOOLEAN: case T_BYTE: // 1 byte
904 assert(value->type() == T_INT, "Agreement.");
905 val = value->get_int();
906 obj->bool_at_put(index, (jboolean)*((jint*)&val));
907 break;
909 default:
910 ShouldNotReachHere();
911 }
912 index++;
913 }
914 }
917 // restore fields of an eliminated object array
918 void Deoptimization::reassign_object_array_elements(frame* fr, RegisterMap* reg_map, ObjectValue* sv, objArrayOop obj) {
919 for (int i = 0; i < sv->field_size(); i++) {
920 StackValue* value = StackValue::create_stack_value(fr, reg_map, sv->field_at(i));
921 assert(value->type() == T_OBJECT, "object element expected");
922 obj->obj_at_put(i, value->get_obj()());
923 }
924 }
927 // restore fields of all eliminated objects and arrays
928 void Deoptimization::reassign_fields(frame* fr, RegisterMap* reg_map, GrowableArray<ScopeValue*>* objects) {
929 for (int i = 0; i < objects->length(); i++) {
930 ObjectValue* sv = (ObjectValue*) objects->at(i);
931 KlassHandle k(java_lang_Class::as_Klass(sv->klass()->as_ConstantOopReadValue()->value()()));
932 Handle obj = sv->value();
933 assert(obj.not_null(), "reallocation was missed");
935 if (k->oop_is_instance()) {
936 InstanceKlass* ik = InstanceKlass::cast(k());
937 FieldReassigner reassign(fr, reg_map, sv, obj());
938 ik->do_nonstatic_fields(&reassign);
939 } else if (k->oop_is_typeArray()) {
940 TypeArrayKlass* ak = TypeArrayKlass::cast(k());
941 reassign_type_array_elements(fr, reg_map, sv, (typeArrayOop) obj(), ak->element_type());
942 } else if (k->oop_is_objArray()) {
943 reassign_object_array_elements(fr, reg_map, sv, (objArrayOop) obj());
944 }
945 }
946 }
949 // relock objects for which synchronization was eliminated
950 void Deoptimization::relock_objects(GrowableArray<MonitorInfo*>* monitors, JavaThread* thread) {
951 for (int i = 0; i < monitors->length(); i++) {
952 MonitorInfo* mon_info = monitors->at(i);
953 if (mon_info->eliminated()) {
954 assert(mon_info->owner() != NULL, "reallocation was missed");
955 Handle obj = Handle(mon_info->owner());
956 markOop mark = obj->mark();
957 if (UseBiasedLocking && mark->has_bias_pattern()) {
958 // New allocated objects may have the mark set to anonymously biased.
959 // Also the deoptimized method may called methods with synchronization
960 // where the thread-local object is bias locked to the current thread.
961 assert(mark->is_biased_anonymously() ||
962 mark->biased_locker() == thread, "should be locked to current thread");
963 // Reset mark word to unbiased prototype.
964 markOop unbiased_prototype = markOopDesc::prototype()->set_age(mark->age());
965 obj->set_mark(unbiased_prototype);
966 }
967 BasicLock* lock = mon_info->lock();
968 ObjectSynchronizer::slow_enter(obj, lock, thread);
969 }
970 assert(mon_info->owner()->is_locked(), "object must be locked now");
971 }
972 }
975 #ifndef PRODUCT
976 // print information about reallocated objects
977 void Deoptimization::print_objects(GrowableArray<ScopeValue*>* objects) {
978 fieldDescriptor fd;
980 for (int i = 0; i < objects->length(); i++) {
981 ObjectValue* sv = (ObjectValue*) objects->at(i);
982 KlassHandle k(java_lang_Class::as_Klass(sv->klass()->as_ConstantOopReadValue()->value()()));
983 Handle obj = sv->value();
985 tty->print(" object <" INTPTR_FORMAT "> of type ", (void *)sv->value()());
986 k->print_value();
987 tty->print(" allocated (%d bytes)", obj->size() * HeapWordSize);
988 tty->cr();
990 if (Verbose) {
991 k->oop_print_on(obj(), tty);
992 }
993 }
994 }
995 #endif
996 #endif // COMPILER2
998 vframeArray* Deoptimization::create_vframeArray(JavaThread* thread, frame fr, RegisterMap *reg_map, GrowableArray<compiledVFrame*>* chunk) {
999 Events::log(thread, "DEOPT PACKING pc=" INTPTR_FORMAT " sp=" INTPTR_FORMAT, fr.pc(), fr.sp());
1001 #ifndef PRODUCT
1002 if (TraceDeoptimization) {
1003 ttyLocker ttyl;
1004 tty->print("DEOPT PACKING thread " INTPTR_FORMAT " ", thread);
1005 fr.print_on(tty);
1006 tty->print_cr(" Virtual frames (innermost first):");
1007 for (int index = 0; index < chunk->length(); index++) {
1008 compiledVFrame* vf = chunk->at(index);
1009 tty->print(" %2d - ", index);
1010 vf->print_value();
1011 int bci = chunk->at(index)->raw_bci();
1012 const char* code_name;
1013 if (bci == SynchronizationEntryBCI) {
1014 code_name = "sync entry";
1015 } else {
1016 Bytecodes::Code code = vf->method()->code_at(bci);
1017 code_name = Bytecodes::name(code);
1018 }
1019 tty->print(" - %s", code_name);
1020 tty->print_cr(" @ bci %d ", bci);
1021 if (Verbose) {
1022 vf->print();
1023 tty->cr();
1024 }
1025 }
1026 }
1027 #endif
1029 // Register map for next frame (used for stack crawl). We capture
1030 // the state of the deopt'ing frame's caller. Thus if we need to
1031 // stuff a C2I adapter we can properly fill in the callee-save
1032 // register locations.
1033 frame caller = fr.sender(reg_map);
1034 int frame_size = caller.sp() - fr.sp();
1036 frame sender = caller;
1038 // Since the Java thread being deoptimized will eventually adjust it's own stack,
1039 // the vframeArray containing the unpacking information is allocated in the C heap.
1040 // For Compiler1, the caller of the deoptimized frame is saved for use by unpack_frames().
1041 vframeArray* array = vframeArray::allocate(thread, frame_size, chunk, reg_map, sender, caller, fr);
1043 // Compare the vframeArray to the collected vframes
1044 assert(array->structural_compare(thread, chunk), "just checking");
1046 #ifndef PRODUCT
1047 if (TraceDeoptimization) {
1048 ttyLocker ttyl;
1049 tty->print_cr(" Created vframeArray " INTPTR_FORMAT, array);
1050 }
1051 #endif // PRODUCT
1053 return array;
1054 }
1057 static void collect_monitors(compiledVFrame* cvf, GrowableArray<Handle>* objects_to_revoke) {
1058 GrowableArray<MonitorInfo*>* monitors = cvf->monitors();
1059 for (int i = 0; i < monitors->length(); i++) {
1060 MonitorInfo* mon_info = monitors->at(i);
1061 if (!mon_info->eliminated() && mon_info->owner() != NULL) {
1062 objects_to_revoke->append(Handle(mon_info->owner()));
1063 }
1064 }
1065 }
1068 void Deoptimization::revoke_biases_of_monitors(JavaThread* thread, frame fr, RegisterMap* map) {
1069 if (!UseBiasedLocking) {
1070 return;
1071 }
1073 GrowableArray<Handle>* objects_to_revoke = new GrowableArray<Handle>();
1075 // Unfortunately we don't have a RegisterMap available in most of
1076 // the places we want to call this routine so we need to walk the
1077 // stack again to update the register map.
1078 if (map == NULL || !map->update_map()) {
1079 StackFrameStream sfs(thread, true);
1080 bool found = false;
1081 while (!found && !sfs.is_done()) {
1082 frame* cur = sfs.current();
1083 sfs.next();
1084 found = cur->id() == fr.id();
1085 }
1086 assert(found, "frame to be deoptimized not found on target thread's stack");
1087 map = sfs.register_map();
1088 }
1090 vframe* vf = vframe::new_vframe(&fr, map, thread);
1091 compiledVFrame* cvf = compiledVFrame::cast(vf);
1092 // Revoke monitors' biases in all scopes
1093 while (!cvf->is_top()) {
1094 collect_monitors(cvf, objects_to_revoke);
1095 cvf = compiledVFrame::cast(cvf->sender());
1096 }
1097 collect_monitors(cvf, objects_to_revoke);
1099 if (SafepointSynchronize::is_at_safepoint()) {
1100 BiasedLocking::revoke_at_safepoint(objects_to_revoke);
1101 } else {
1102 BiasedLocking::revoke(objects_to_revoke);
1103 }
1104 }
1107 void Deoptimization::revoke_biases_of_monitors(CodeBlob* cb) {
1108 if (!UseBiasedLocking) {
1109 return;
1110 }
1112 assert(SafepointSynchronize::is_at_safepoint(), "must only be called from safepoint");
1113 GrowableArray<Handle>* objects_to_revoke = new GrowableArray<Handle>();
1114 for (JavaThread* jt = Threads::first(); jt != NULL ; jt = jt->next()) {
1115 if (jt->has_last_Java_frame()) {
1116 StackFrameStream sfs(jt, true);
1117 while (!sfs.is_done()) {
1118 frame* cur = sfs.current();
1119 if (cb->contains(cur->pc())) {
1120 vframe* vf = vframe::new_vframe(cur, sfs.register_map(), jt);
1121 compiledVFrame* cvf = compiledVFrame::cast(vf);
1122 // Revoke monitors' biases in all scopes
1123 while (!cvf->is_top()) {
1124 collect_monitors(cvf, objects_to_revoke);
1125 cvf = compiledVFrame::cast(cvf->sender());
1126 }
1127 collect_monitors(cvf, objects_to_revoke);
1128 }
1129 sfs.next();
1130 }
1131 }
1132 }
1133 BiasedLocking::revoke_at_safepoint(objects_to_revoke);
1134 }
1137 void Deoptimization::deoptimize_single_frame(JavaThread* thread, frame fr) {
1138 assert(fr.can_be_deoptimized(), "checking frame type");
1140 gather_statistics(Reason_constraint, Action_none, Bytecodes::_illegal);
1142 // Patch the nmethod so that when execution returns to it we will
1143 // deopt the execution state and return to the interpreter.
1144 fr.deoptimize(thread);
1145 }
1147 void Deoptimization::deoptimize(JavaThread* thread, frame fr, RegisterMap *map) {
1148 // Deoptimize only if the frame comes from compile code.
1149 // Do not deoptimize the frame which is already patched
1150 // during the execution of the loops below.
1151 if (!fr.is_compiled_frame() || fr.is_deoptimized_frame()) {
1152 return;
1153 }
1154 ResourceMark rm;
1155 DeoptimizationMarker dm;
1156 if (UseBiasedLocking) {
1157 revoke_biases_of_monitors(thread, fr, map);
1158 }
1159 deoptimize_single_frame(thread, fr);
1161 }
1164 void Deoptimization::deoptimize_frame_internal(JavaThread* thread, intptr_t* id) {
1165 assert(thread == Thread::current() || SafepointSynchronize::is_at_safepoint(),
1166 "can only deoptimize other thread at a safepoint");
1167 // Compute frame and register map based on thread and sp.
1168 RegisterMap reg_map(thread, UseBiasedLocking);
1169 frame fr = thread->last_frame();
1170 while (fr.id() != id) {
1171 fr = fr.sender(®_map);
1172 }
1173 deoptimize(thread, fr, ®_map);
1174 }
1177 void Deoptimization::deoptimize_frame(JavaThread* thread, intptr_t* id) {
1178 if (thread == Thread::current()) {
1179 Deoptimization::deoptimize_frame_internal(thread, id);
1180 } else {
1181 VM_DeoptimizeFrame deopt(thread, id);
1182 VMThread::execute(&deopt);
1183 }
1184 }
1187 // JVMTI PopFrame support
1188 JRT_LEAF(void, Deoptimization::popframe_preserve_args(JavaThread* thread, int bytes_to_save, void* start_address))
1189 {
1190 thread->popframe_preserve_args(in_ByteSize(bytes_to_save), start_address);
1191 }
1192 JRT_END
1195 #if defined(COMPILER2) || defined(SHARK)
1196 void Deoptimization::load_class_by_index(constantPoolHandle constant_pool, int index, TRAPS) {
1197 // in case of an unresolved klass entry, load the class.
1198 if (constant_pool->tag_at(index).is_unresolved_klass()) {
1199 Klass* tk = constant_pool->klass_at(index, CHECK);
1200 return;
1201 }
1203 if (!constant_pool->tag_at(index).is_symbol()) return;
1205 Handle class_loader (THREAD, constant_pool->pool_holder()->class_loader());
1206 Symbol* symbol = constant_pool->symbol_at(index);
1208 // class name?
1209 if (symbol->byte_at(0) != '(') {
1210 Handle protection_domain (THREAD, constant_pool->pool_holder()->protection_domain());
1211 SystemDictionary::resolve_or_null(symbol, class_loader, protection_domain, CHECK);
1212 return;
1213 }
1215 // then it must be a signature!
1216 ResourceMark rm(THREAD);
1217 for (SignatureStream ss(symbol); !ss.is_done(); ss.next()) {
1218 if (ss.is_object()) {
1219 Symbol* class_name = ss.as_symbol(CHECK);
1220 Handle protection_domain (THREAD, constant_pool->pool_holder()->protection_domain());
1221 SystemDictionary::resolve_or_null(class_name, class_loader, protection_domain, CHECK);
1222 }
1223 }
1224 }
1227 void Deoptimization::load_class_by_index(constantPoolHandle constant_pool, int index) {
1228 EXCEPTION_MARK;
1229 load_class_by_index(constant_pool, index, THREAD);
1230 if (HAS_PENDING_EXCEPTION) {
1231 // Exception happened during classloading. We ignore the exception here, since it
1232 // is going to be rethrown since the current activation is going to be deoptimized and
1233 // the interpreter will re-execute the bytecode.
1234 CLEAR_PENDING_EXCEPTION;
1235 // Class loading called java code which may have caused a stack
1236 // overflow. If the exception was thrown right before the return
1237 // to the runtime the stack is no longer guarded. Reguard the
1238 // stack otherwise if we return to the uncommon trap blob and the
1239 // stack bang causes a stack overflow we crash.
1240 assert(THREAD->is_Java_thread(), "only a java thread can be here");
1241 JavaThread* thread = (JavaThread*)THREAD;
1242 bool guard_pages_enabled = thread->stack_yellow_zone_enabled();
1243 if (!guard_pages_enabled) guard_pages_enabled = thread->reguard_stack();
1244 assert(guard_pages_enabled, "stack banging in uncommon trap blob may cause crash");
1245 }
1246 }
1248 JRT_ENTRY(void, Deoptimization::uncommon_trap_inner(JavaThread* thread, jint trap_request)) {
1249 HandleMark hm;
1251 // uncommon_trap() is called at the beginning of the uncommon trap
1252 // handler. Note this fact before we start generating temporary frames
1253 // that can confuse an asynchronous stack walker. This counter is
1254 // decremented at the end of unpack_frames().
1255 thread->inc_in_deopt_handler();
1257 // We need to update the map if we have biased locking.
1258 RegisterMap reg_map(thread, UseBiasedLocking);
1259 frame stub_frame = thread->last_frame();
1260 frame fr = stub_frame.sender(®_map);
1261 // Make sure the calling nmethod is not getting deoptimized and removed
1262 // before we are done with it.
1263 nmethodLocker nl(fr.pc());
1265 // Log a message
1266 Events::log(thread, "Uncommon trap: trap_request=" PTR32_FORMAT " fr.pc=" INTPTR_FORMAT,
1267 trap_request, fr.pc());
1269 {
1270 ResourceMark rm;
1272 // Revoke biases of any monitors in the frame to ensure we can migrate them
1273 revoke_biases_of_monitors(thread, fr, ®_map);
1275 DeoptReason reason = trap_request_reason(trap_request);
1276 DeoptAction action = trap_request_action(trap_request);
1277 jint unloaded_class_index = trap_request_index(trap_request); // CP idx or -1
1279 vframe* vf = vframe::new_vframe(&fr, ®_map, thread);
1280 compiledVFrame* cvf = compiledVFrame::cast(vf);
1282 nmethod* nm = cvf->code();
1284 ScopeDesc* trap_scope = cvf->scope();
1285 methodHandle trap_method = trap_scope->method();
1286 int trap_bci = trap_scope->bci();
1287 Bytecodes::Code trap_bc = trap_method->java_code_at(trap_bci);
1289 // Record this event in the histogram.
1290 gather_statistics(reason, action, trap_bc);
1292 // Ensure that we can record deopt. history:
1293 // Need MDO to record RTM code generation state.
1294 bool create_if_missing = ProfileTraps RTM_OPT_ONLY( || UseRTMLocking );
1296 MethodData* trap_mdo =
1297 get_method_data(thread, trap_method, create_if_missing);
1299 // Log a message
1300 Events::log_deopt_message(thread, "Uncommon trap: reason=%s action=%s pc=" INTPTR_FORMAT " method=%s @ %d",
1301 trap_reason_name(reason), trap_action_name(action), fr.pc(),
1302 trap_method->name_and_sig_as_C_string(), trap_bci);
1304 // Print a bunch of diagnostics, if requested.
1305 if (TraceDeoptimization || LogCompilation) {
1306 ResourceMark rm;
1307 ttyLocker ttyl;
1308 char buf[100];
1309 if (xtty != NULL) {
1310 xtty->begin_head("uncommon_trap thread='" UINTX_FORMAT"' %s",
1311 os::current_thread_id(),
1312 format_trap_request(buf, sizeof(buf), trap_request));
1313 nm->log_identity(xtty);
1314 }
1315 Symbol* class_name = NULL;
1316 bool unresolved = false;
1317 if (unloaded_class_index >= 0) {
1318 constantPoolHandle constants (THREAD, trap_method->constants());
1319 if (constants->tag_at(unloaded_class_index).is_unresolved_klass()) {
1320 class_name = constants->klass_name_at(unloaded_class_index);
1321 unresolved = true;
1322 if (xtty != NULL)
1323 xtty->print(" unresolved='1'");
1324 } else if (constants->tag_at(unloaded_class_index).is_symbol()) {
1325 class_name = constants->symbol_at(unloaded_class_index);
1326 }
1327 if (xtty != NULL)
1328 xtty->name(class_name);
1329 }
1330 if (xtty != NULL && trap_mdo != NULL) {
1331 // Dump the relevant MDO state.
1332 // This is the deopt count for the current reason, any previous
1333 // reasons or recompiles seen at this point.
1334 int dcnt = trap_mdo->trap_count(reason);
1335 if (dcnt != 0)
1336 xtty->print(" count='%d'", dcnt);
1337 ProfileData* pdata = trap_mdo->bci_to_data(trap_bci);
1338 int dos = (pdata == NULL)? 0: pdata->trap_state();
1339 if (dos != 0) {
1340 xtty->print(" state='%s'", format_trap_state(buf, sizeof(buf), dos));
1341 if (trap_state_is_recompiled(dos)) {
1342 int recnt2 = trap_mdo->overflow_recompile_count();
1343 if (recnt2 != 0)
1344 xtty->print(" recompiles2='%d'", recnt2);
1345 }
1346 }
1347 }
1348 if (xtty != NULL) {
1349 xtty->stamp();
1350 xtty->end_head();
1351 }
1352 if (TraceDeoptimization) { // make noise on the tty
1353 tty->print("Uncommon trap occurred in");
1354 nm->method()->print_short_name(tty);
1355 tty->print(" (@" INTPTR_FORMAT ") thread=" UINTX_FORMAT " reason=%s action=%s unloaded_class_index=%d",
1356 fr.pc(),
1357 os::current_thread_id(),
1358 trap_reason_name(reason),
1359 trap_action_name(action),
1360 unloaded_class_index);
1361 if (class_name != NULL) {
1362 tty->print(unresolved ? " unresolved class: " : " symbol: ");
1363 class_name->print_symbol_on(tty);
1364 }
1365 tty->cr();
1366 }
1367 if (xtty != NULL) {
1368 // Log the precise location of the trap.
1369 for (ScopeDesc* sd = trap_scope; ; sd = sd->sender()) {
1370 xtty->begin_elem("jvms bci='%d'", sd->bci());
1371 xtty->method(sd->method());
1372 xtty->end_elem();
1373 if (sd->is_top()) break;
1374 }
1375 xtty->tail("uncommon_trap");
1376 }
1377 }
1378 // (End diagnostic printout.)
1380 // Load class if necessary
1381 if (unloaded_class_index >= 0) {
1382 constantPoolHandle constants(THREAD, trap_method->constants());
1383 load_class_by_index(constants, unloaded_class_index);
1384 }
1386 // Flush the nmethod if necessary and desirable.
1387 //
1388 // We need to avoid situations where we are re-flushing the nmethod
1389 // because of a hot deoptimization site. Repeated flushes at the same
1390 // point need to be detected by the compiler and avoided. If the compiler
1391 // cannot avoid them (or has a bug and "refuses" to avoid them), this
1392 // module must take measures to avoid an infinite cycle of recompilation
1393 // and deoptimization. There are several such measures:
1394 //
1395 // 1. If a recompilation is ordered a second time at some site X
1396 // and for the same reason R, the action is adjusted to 'reinterpret',
1397 // to give the interpreter time to exercise the method more thoroughly.
1398 // If this happens, the method's overflow_recompile_count is incremented.
1399 //
1400 // 2. If the compiler fails to reduce the deoptimization rate, then
1401 // the method's overflow_recompile_count will begin to exceed the set
1402 // limit PerBytecodeRecompilationCutoff. If this happens, the action
1403 // is adjusted to 'make_not_compilable', and the method is abandoned
1404 // to the interpreter. This is a performance hit for hot methods,
1405 // but is better than a disastrous infinite cycle of recompilations.
1406 // (Actually, only the method containing the site X is abandoned.)
1407 //
1408 // 3. In parallel with the previous measures, if the total number of
1409 // recompilations of a method exceeds the much larger set limit
1410 // PerMethodRecompilationCutoff, the method is abandoned.
1411 // This should only happen if the method is very large and has
1412 // many "lukewarm" deoptimizations. The code which enforces this
1413 // limit is elsewhere (class nmethod, class Method).
1414 //
1415 // Note that the per-BCI 'is_recompiled' bit gives the compiler one chance
1416 // to recompile at each bytecode independently of the per-BCI cutoff.
1417 //
1418 // The decision to update code is up to the compiler, and is encoded
1419 // in the Action_xxx code. If the compiler requests Action_none
1420 // no trap state is changed, no compiled code is changed, and the
1421 // computation suffers along in the interpreter.
1422 //
1423 // The other action codes specify various tactics for decompilation
1424 // and recompilation. Action_maybe_recompile is the loosest, and
1425 // allows the compiled code to stay around until enough traps are seen,
1426 // and until the compiler gets around to recompiling the trapping method.
1427 //
1428 // The other actions cause immediate removal of the present code.
1430 bool update_trap_state = true;
1431 bool make_not_entrant = false;
1432 bool make_not_compilable = false;
1433 bool reprofile = false;
1434 switch (action) {
1435 case Action_none:
1436 // Keep the old code.
1437 update_trap_state = false;
1438 break;
1439 case Action_maybe_recompile:
1440 // Do not need to invalidate the present code, but we can
1441 // initiate another
1442 // Start compiler without (necessarily) invalidating the nmethod.
1443 // The system will tolerate the old code, but new code should be
1444 // generated when possible.
1445 break;
1446 case Action_reinterpret:
1447 // Go back into the interpreter for a while, and then consider
1448 // recompiling form scratch.
1449 make_not_entrant = true;
1450 // Reset invocation counter for outer most method.
1451 // This will allow the interpreter to exercise the bytecodes
1452 // for a while before recompiling.
1453 // By contrast, Action_make_not_entrant is immediate.
1454 //
1455 // Note that the compiler will track null_check, null_assert,
1456 // range_check, and class_check events and log them as if they
1457 // had been traps taken from compiled code. This will update
1458 // the MDO trap history so that the next compilation will
1459 // properly detect hot trap sites.
1460 reprofile = true;
1461 break;
1462 case Action_make_not_entrant:
1463 // Request immediate recompilation, and get rid of the old code.
1464 // Make them not entrant, so next time they are called they get
1465 // recompiled. Unloaded classes are loaded now so recompile before next
1466 // time they are called. Same for uninitialized. The interpreter will
1467 // link the missing class, if any.
1468 make_not_entrant = true;
1469 break;
1470 case Action_make_not_compilable:
1471 // Give up on compiling this method at all.
1472 make_not_entrant = true;
1473 make_not_compilable = true;
1474 break;
1475 default:
1476 ShouldNotReachHere();
1477 }
1479 // Setting +ProfileTraps fixes the following, on all platforms:
1480 // 4852688: ProfileInterpreter is off by default for ia64. The result is
1481 // infinite heroic-opt-uncommon-trap/deopt/recompile cycles, since the
1482 // recompile relies on a MethodData* to record heroic opt failures.
1484 // Whether the interpreter is producing MDO data or not, we also need
1485 // to use the MDO to detect hot deoptimization points and control
1486 // aggressive optimization.
1487 bool inc_recompile_count = false;
1488 ProfileData* pdata = NULL;
1489 if (ProfileTraps && update_trap_state && trap_mdo != NULL) {
1490 assert(trap_mdo == get_method_data(thread, trap_method, false), "sanity");
1491 uint this_trap_count = 0;
1492 bool maybe_prior_trap = false;
1493 bool maybe_prior_recompile = false;
1494 pdata = query_update_method_data(trap_mdo, trap_bci, reason,
1495 nm->method(),
1496 //outputs:
1497 this_trap_count,
1498 maybe_prior_trap,
1499 maybe_prior_recompile);
1500 // Because the interpreter also counts null, div0, range, and class
1501 // checks, these traps from compiled code are double-counted.
1502 // This is harmless; it just means that the PerXTrapLimit values
1503 // are in effect a little smaller than they look.
1505 DeoptReason per_bc_reason = reason_recorded_per_bytecode_if_any(reason);
1506 if (per_bc_reason != Reason_none) {
1507 // Now take action based on the partially known per-BCI history.
1508 if (maybe_prior_trap
1509 && this_trap_count >= (uint)PerBytecodeTrapLimit) {
1510 // If there are too many traps at this BCI, force a recompile.
1511 // This will allow the compiler to see the limit overflow, and
1512 // take corrective action, if possible. The compiler generally
1513 // does not use the exact PerBytecodeTrapLimit value, but instead
1514 // changes its tactics if it sees any traps at all. This provides
1515 // a little hysteresis, delaying a recompile until a trap happens
1516 // several times.
1517 //
1518 // Actually, since there is only one bit of counter per BCI,
1519 // the possible per-BCI counts are {0,1,(per-method count)}.
1520 // This produces accurate results if in fact there is only
1521 // one hot trap site, but begins to get fuzzy if there are
1522 // many sites. For example, if there are ten sites each
1523 // trapping two or more times, they each get the blame for
1524 // all of their traps.
1525 make_not_entrant = true;
1526 }
1528 // Detect repeated recompilation at the same BCI, and enforce a limit.
1529 if (make_not_entrant && maybe_prior_recompile) {
1530 // More than one recompile at this point.
1531 inc_recompile_count = maybe_prior_trap;
1532 }
1533 } else {
1534 // For reasons which are not recorded per-bytecode, we simply
1535 // force recompiles unconditionally.
1536 // (Note that PerMethodRecompilationCutoff is enforced elsewhere.)
1537 make_not_entrant = true;
1538 }
1540 // Go back to the compiler if there are too many traps in this method.
1541 if (this_trap_count >= per_method_trap_limit(reason)) {
1542 // If there are too many traps in this method, force a recompile.
1543 // This will allow the compiler to see the limit overflow, and
1544 // take corrective action, if possible.
1545 // (This condition is an unlikely backstop only, because the
1546 // PerBytecodeTrapLimit is more likely to take effect first,
1547 // if it is applicable.)
1548 make_not_entrant = true;
1549 }
1551 // Here's more hysteresis: If there has been a recompile at
1552 // this trap point already, run the method in the interpreter
1553 // for a while to exercise it more thoroughly.
1554 if (make_not_entrant && maybe_prior_recompile && maybe_prior_trap) {
1555 reprofile = true;
1556 }
1558 }
1560 // Take requested actions on the method:
1562 // Recompile
1563 if (make_not_entrant) {
1564 if (!nm->make_not_entrant()) {
1565 return; // the call did not change nmethod's state
1566 }
1568 if (pdata != NULL) {
1569 // Record the recompilation event, if any.
1570 int tstate0 = pdata->trap_state();
1571 int tstate1 = trap_state_set_recompiled(tstate0, true);
1572 if (tstate1 != tstate0)
1573 pdata->set_trap_state(tstate1);
1574 }
1576 #if INCLUDE_RTM_OPT
1577 // Restart collecting RTM locking abort statistic if the method
1578 // is recompiled for a reason other than RTM state change.
1579 // Assume that in new recompiled code the statistic could be different,
1580 // for example, due to different inlining.
1581 if ((reason != Reason_rtm_state_change) && (trap_mdo != NULL) &&
1582 UseRTMDeopt && (nm->rtm_state() != ProfileRTM)) {
1583 trap_mdo->atomic_set_rtm_state(ProfileRTM);
1584 }
1585 #endif
1586 }
1588 if (inc_recompile_count) {
1589 trap_mdo->inc_overflow_recompile_count();
1590 if ((uint)trap_mdo->overflow_recompile_count() >
1591 (uint)PerBytecodeRecompilationCutoff) {
1592 // Give up on the method containing the bad BCI.
1593 if (trap_method() == nm->method()) {
1594 make_not_compilable = true;
1595 } else {
1596 trap_method->set_not_compilable(CompLevel_full_optimization, true, "overflow_recompile_count > PerBytecodeRecompilationCutoff");
1597 // But give grace to the enclosing nm->method().
1598 }
1599 }
1600 }
1602 // Reprofile
1603 if (reprofile) {
1604 CompilationPolicy::policy()->reprofile(trap_scope, nm->is_osr_method());
1605 }
1607 // Give up compiling
1608 if (make_not_compilable && !nm->method()->is_not_compilable(CompLevel_full_optimization)) {
1609 assert(make_not_entrant, "consistent");
1610 nm->method()->set_not_compilable(CompLevel_full_optimization);
1611 }
1613 } // Free marked resources
1615 }
1616 JRT_END
1618 MethodData*
1619 Deoptimization::get_method_data(JavaThread* thread, methodHandle m,
1620 bool create_if_missing) {
1621 Thread* THREAD = thread;
1622 MethodData* mdo = m()->method_data();
1623 if (mdo == NULL && create_if_missing && !HAS_PENDING_EXCEPTION) {
1624 // Build an MDO. Ignore errors like OutOfMemory;
1625 // that simply means we won't have an MDO to update.
1626 Method::build_interpreter_method_data(m, THREAD);
1627 if (HAS_PENDING_EXCEPTION) {
1628 assert((PENDING_EXCEPTION->is_a(SystemDictionary::OutOfMemoryError_klass())), "we expect only an OOM error here");
1629 CLEAR_PENDING_EXCEPTION;
1630 }
1631 mdo = m()->method_data();
1632 }
1633 return mdo;
1634 }
1636 ProfileData*
1637 Deoptimization::query_update_method_data(MethodData* trap_mdo,
1638 int trap_bci,
1639 Deoptimization::DeoptReason reason,
1640 Method* compiled_method,
1641 //outputs:
1642 uint& ret_this_trap_count,
1643 bool& ret_maybe_prior_trap,
1644 bool& ret_maybe_prior_recompile) {
1645 uint prior_trap_count = trap_mdo->trap_count(reason);
1646 uint this_trap_count = trap_mdo->inc_trap_count(reason);
1648 // If the runtime cannot find a place to store trap history,
1649 // it is estimated based on the general condition of the method.
1650 // If the method has ever been recompiled, or has ever incurred
1651 // a trap with the present reason , then this BCI is assumed
1652 // (pessimistically) to be the culprit.
1653 bool maybe_prior_trap = (prior_trap_count != 0);
1654 bool maybe_prior_recompile = (trap_mdo->decompile_count() != 0);
1655 ProfileData* pdata = NULL;
1658 // For reasons which are recorded per bytecode, we check per-BCI data.
1659 DeoptReason per_bc_reason = reason_recorded_per_bytecode_if_any(reason);
1660 if (per_bc_reason != Reason_none) {
1661 // Find the profile data for this BCI. If there isn't one,
1662 // try to allocate one from the MDO's set of spares.
1663 // This will let us detect a repeated trap at this point.
1664 pdata = trap_mdo->allocate_bci_to_data(trap_bci, reason_is_speculate(reason) ? compiled_method : NULL);
1666 if (pdata != NULL) {
1667 if (reason_is_speculate(reason) && !pdata->is_SpeculativeTrapData()) {
1668 if (LogCompilation && xtty != NULL) {
1669 ttyLocker ttyl;
1670 // no more room for speculative traps in this MDO
1671 xtty->elem("speculative_traps_oom");
1672 }
1673 }
1674 // Query the trap state of this profile datum.
1675 int tstate0 = pdata->trap_state();
1676 if (!trap_state_has_reason(tstate0, per_bc_reason))
1677 maybe_prior_trap = false;
1678 if (!trap_state_is_recompiled(tstate0))
1679 maybe_prior_recompile = false;
1681 // Update the trap state of this profile datum.
1682 int tstate1 = tstate0;
1683 // Record the reason.
1684 tstate1 = trap_state_add_reason(tstate1, per_bc_reason);
1685 // Store the updated state on the MDO, for next time.
1686 if (tstate1 != tstate0)
1687 pdata->set_trap_state(tstate1);
1688 } else {
1689 if (LogCompilation && xtty != NULL) {
1690 ttyLocker ttyl;
1691 // Missing MDP? Leave a small complaint in the log.
1692 xtty->elem("missing_mdp bci='%d'", trap_bci);
1693 }
1694 }
1695 }
1697 // Return results:
1698 ret_this_trap_count = this_trap_count;
1699 ret_maybe_prior_trap = maybe_prior_trap;
1700 ret_maybe_prior_recompile = maybe_prior_recompile;
1701 return pdata;
1702 }
1704 void
1705 Deoptimization::update_method_data_from_interpreter(MethodData* trap_mdo, int trap_bci, int reason) {
1706 ResourceMark rm;
1707 // Ignored outputs:
1708 uint ignore_this_trap_count;
1709 bool ignore_maybe_prior_trap;
1710 bool ignore_maybe_prior_recompile;
1711 assert(!reason_is_speculate(reason), "reason speculate only used by compiler");
1712 query_update_method_data(trap_mdo, trap_bci,
1713 (DeoptReason)reason,
1714 NULL,
1715 ignore_this_trap_count,
1716 ignore_maybe_prior_trap,
1717 ignore_maybe_prior_recompile);
1718 }
1720 Deoptimization::UnrollBlock* Deoptimization::uncommon_trap(JavaThread* thread, jint trap_request) {
1722 // Still in Java no safepoints
1723 {
1724 // This enters VM and may safepoint
1725 uncommon_trap_inner(thread, trap_request);
1726 }
1727 return fetch_unroll_info_helper(thread);
1728 }
1730 // Local derived constants.
1731 // Further breakdown of DataLayout::trap_state, as promised by DataLayout.
1732 const int DS_REASON_MASK = DataLayout::trap_mask >> 1;
1733 const int DS_RECOMPILE_BIT = DataLayout::trap_mask - DS_REASON_MASK;
1735 //---------------------------trap_state_reason---------------------------------
1736 Deoptimization::DeoptReason
1737 Deoptimization::trap_state_reason(int trap_state) {
1738 // This assert provides the link between the width of DataLayout::trap_bits
1739 // and the encoding of "recorded" reasons. It ensures there are enough
1740 // bits to store all needed reasons in the per-BCI MDO profile.
1741 assert(DS_REASON_MASK >= Reason_RECORDED_LIMIT, "enough bits");
1742 int recompile_bit = (trap_state & DS_RECOMPILE_BIT);
1743 trap_state -= recompile_bit;
1744 if (trap_state == DS_REASON_MASK) {
1745 return Reason_many;
1746 } else {
1747 assert((int)Reason_none == 0, "state=0 => Reason_none");
1748 return (DeoptReason)trap_state;
1749 }
1750 }
1751 //-------------------------trap_state_has_reason-------------------------------
1752 int Deoptimization::trap_state_has_reason(int trap_state, int reason) {
1753 assert(reason_is_recorded_per_bytecode((DeoptReason)reason), "valid reason");
1754 assert(DS_REASON_MASK >= Reason_RECORDED_LIMIT, "enough bits");
1755 int recompile_bit = (trap_state & DS_RECOMPILE_BIT);
1756 trap_state -= recompile_bit;
1757 if (trap_state == DS_REASON_MASK) {
1758 return -1; // true, unspecifically (bottom of state lattice)
1759 } else if (trap_state == reason) {
1760 return 1; // true, definitely
1761 } else if (trap_state == 0) {
1762 return 0; // false, definitely (top of state lattice)
1763 } else {
1764 return 0; // false, definitely
1765 }
1766 }
1767 //-------------------------trap_state_add_reason-------------------------------
1768 int Deoptimization::trap_state_add_reason(int trap_state, int reason) {
1769 assert(reason_is_recorded_per_bytecode((DeoptReason)reason) || reason == Reason_many, "valid reason");
1770 int recompile_bit = (trap_state & DS_RECOMPILE_BIT);
1771 trap_state -= recompile_bit;
1772 if (trap_state == DS_REASON_MASK) {
1773 return trap_state + recompile_bit; // already at state lattice bottom
1774 } else if (trap_state == reason) {
1775 return trap_state + recompile_bit; // the condition is already true
1776 } else if (trap_state == 0) {
1777 return reason + recompile_bit; // no condition has yet been true
1778 } else {
1779 return DS_REASON_MASK + recompile_bit; // fall to state lattice bottom
1780 }
1781 }
1782 //-----------------------trap_state_is_recompiled------------------------------
1783 bool Deoptimization::trap_state_is_recompiled(int trap_state) {
1784 return (trap_state & DS_RECOMPILE_BIT) != 0;
1785 }
1786 //-----------------------trap_state_set_recompiled-----------------------------
1787 int Deoptimization::trap_state_set_recompiled(int trap_state, bool z) {
1788 if (z) return trap_state | DS_RECOMPILE_BIT;
1789 else return trap_state & ~DS_RECOMPILE_BIT;
1790 }
1791 //---------------------------format_trap_state---------------------------------
1792 // This is used for debugging and diagnostics, including LogFile output.
1793 const char* Deoptimization::format_trap_state(char* buf, size_t buflen,
1794 int trap_state) {
1795 DeoptReason reason = trap_state_reason(trap_state);
1796 bool recomp_flag = trap_state_is_recompiled(trap_state);
1797 // Re-encode the state from its decoded components.
1798 int decoded_state = 0;
1799 if (reason_is_recorded_per_bytecode(reason) || reason == Reason_many)
1800 decoded_state = trap_state_add_reason(decoded_state, reason);
1801 if (recomp_flag)
1802 decoded_state = trap_state_set_recompiled(decoded_state, recomp_flag);
1803 // If the state re-encodes properly, format it symbolically.
1804 // Because this routine is used for debugging and diagnostics,
1805 // be robust even if the state is a strange value.
1806 size_t len;
1807 if (decoded_state != trap_state) {
1808 // Random buggy state that doesn't decode??
1809 len = jio_snprintf(buf, buflen, "#%d", trap_state);
1810 } else {
1811 len = jio_snprintf(buf, buflen, "%s%s",
1812 trap_reason_name(reason),
1813 recomp_flag ? " recompiled" : "");
1814 }
1815 if (len >= buflen)
1816 buf[buflen-1] = '\0';
1817 return buf;
1818 }
1821 //--------------------------------statics--------------------------------------
1822 Deoptimization::DeoptAction Deoptimization::_unloaded_action
1823 = Deoptimization::Action_reinterpret;
1824 const char* Deoptimization::_trap_reason_name[Reason_LIMIT] = {
1825 // Note: Keep this in sync. with enum DeoptReason.
1826 "none",
1827 "null_check",
1828 "null_assert",
1829 "range_check",
1830 "class_check",
1831 "array_check",
1832 "intrinsic",
1833 "bimorphic",
1834 "unloaded",
1835 "uninitialized",
1836 "unreached",
1837 "unhandled",
1838 "constraint",
1839 "div0_check",
1840 "age",
1841 "predicate",
1842 "loop_limit_check",
1843 "speculate_class_check",
1844 "rtm_state_change"
1845 };
1846 const char* Deoptimization::_trap_action_name[Action_LIMIT] = {
1847 // Note: Keep this in sync. with enum DeoptAction.
1848 "none",
1849 "maybe_recompile",
1850 "reinterpret",
1851 "make_not_entrant",
1852 "make_not_compilable"
1853 };
1855 const char* Deoptimization::trap_reason_name(int reason) {
1856 if (reason == Reason_many) return "many";
1857 if ((uint)reason < Reason_LIMIT)
1858 return _trap_reason_name[reason];
1859 static char buf[20];
1860 sprintf(buf, "reason%d", reason);
1861 return buf;
1862 }
1863 const char* Deoptimization::trap_action_name(int action) {
1864 if ((uint)action < Action_LIMIT)
1865 return _trap_action_name[action];
1866 static char buf[20];
1867 sprintf(buf, "action%d", action);
1868 return buf;
1869 }
1871 // This is used for debugging and diagnostics, including LogFile output.
1872 const char* Deoptimization::format_trap_request(char* buf, size_t buflen,
1873 int trap_request) {
1874 jint unloaded_class_index = trap_request_index(trap_request);
1875 const char* reason = trap_reason_name(trap_request_reason(trap_request));
1876 const char* action = trap_action_name(trap_request_action(trap_request));
1877 size_t len;
1878 if (unloaded_class_index < 0) {
1879 len = jio_snprintf(buf, buflen, "reason='%s' action='%s'",
1880 reason, action);
1881 } else {
1882 len = jio_snprintf(buf, buflen, "reason='%s' action='%s' index='%d'",
1883 reason, action, unloaded_class_index);
1884 }
1885 if (len >= buflen)
1886 buf[buflen-1] = '\0';
1887 return buf;
1888 }
1890 juint Deoptimization::_deoptimization_hist
1891 [Deoptimization::Reason_LIMIT]
1892 [1 + Deoptimization::Action_LIMIT]
1893 [Deoptimization::BC_CASE_LIMIT]
1894 = {0};
1896 enum {
1897 LSB_BITS = 8,
1898 LSB_MASK = right_n_bits(LSB_BITS)
1899 };
1901 void Deoptimization::gather_statistics(DeoptReason reason, DeoptAction action,
1902 Bytecodes::Code bc) {
1903 assert(reason >= 0 && reason < Reason_LIMIT, "oob");
1904 assert(action >= 0 && action < Action_LIMIT, "oob");
1905 _deoptimization_hist[Reason_none][0][0] += 1; // total
1906 _deoptimization_hist[reason][0][0] += 1; // per-reason total
1907 juint* cases = _deoptimization_hist[reason][1+action];
1908 juint* bc_counter_addr = NULL;
1909 juint bc_counter = 0;
1910 // Look for an unused counter, or an exact match to this BC.
1911 if (bc != Bytecodes::_illegal) {
1912 for (int bc_case = 0; bc_case < BC_CASE_LIMIT; bc_case++) {
1913 juint* counter_addr = &cases[bc_case];
1914 juint counter = *counter_addr;
1915 if ((counter == 0 && bc_counter_addr == NULL)
1916 || (Bytecodes::Code)(counter & LSB_MASK) == bc) {
1917 // this counter is either free or is already devoted to this BC
1918 bc_counter_addr = counter_addr;
1919 bc_counter = counter | bc;
1920 }
1921 }
1922 }
1923 if (bc_counter_addr == NULL) {
1924 // Overflow, or no given bytecode.
1925 bc_counter_addr = &cases[BC_CASE_LIMIT-1];
1926 bc_counter = (*bc_counter_addr & ~LSB_MASK); // clear LSB
1927 }
1928 *bc_counter_addr = bc_counter + (1 << LSB_BITS);
1929 }
1931 jint Deoptimization::total_deoptimization_count() {
1932 return _deoptimization_hist[Reason_none][0][0];
1933 }
1935 jint Deoptimization::deoptimization_count(DeoptReason reason) {
1936 assert(reason >= 0 && reason < Reason_LIMIT, "oob");
1937 return _deoptimization_hist[reason][0][0];
1938 }
1940 void Deoptimization::print_statistics() {
1941 juint total = total_deoptimization_count();
1942 juint account = total;
1943 if (total != 0) {
1944 ttyLocker ttyl;
1945 if (xtty != NULL) xtty->head("statistics type='deoptimization'");
1946 tty->print_cr("Deoptimization traps recorded:");
1947 #define PRINT_STAT_LINE(name, r) \
1948 tty->print_cr(" %4d (%4.1f%%) %s", (int)(r), ((r) * 100.0) / total, name);
1949 PRINT_STAT_LINE("total", total);
1950 // For each non-zero entry in the histogram, print the reason,
1951 // the action, and (if specifically known) the type of bytecode.
1952 for (int reason = 0; reason < Reason_LIMIT; reason++) {
1953 for (int action = 0; action < Action_LIMIT; action++) {
1954 juint* cases = _deoptimization_hist[reason][1+action];
1955 for (int bc_case = 0; bc_case < BC_CASE_LIMIT; bc_case++) {
1956 juint counter = cases[bc_case];
1957 if (counter != 0) {
1958 char name[1*K];
1959 Bytecodes::Code bc = (Bytecodes::Code)(counter & LSB_MASK);
1960 if (bc_case == BC_CASE_LIMIT && (int)bc == 0)
1961 bc = Bytecodes::_illegal;
1962 sprintf(name, "%s/%s/%s",
1963 trap_reason_name(reason),
1964 trap_action_name(action),
1965 Bytecodes::is_defined(bc)? Bytecodes::name(bc): "other");
1966 juint r = counter >> LSB_BITS;
1967 tty->print_cr(" %40s: " UINT32_FORMAT " (%.1f%%)", name, r, (r * 100.0) / total);
1968 account -= r;
1969 }
1970 }
1971 }
1972 }
1973 if (account != 0) {
1974 PRINT_STAT_LINE("unaccounted", account);
1975 }
1976 #undef PRINT_STAT_LINE
1977 if (xtty != NULL) xtty->tail("statistics");
1978 }
1979 }
1980 #else // COMPILER2 || SHARK
1983 // Stubs for C1 only system.
1984 bool Deoptimization::trap_state_is_recompiled(int trap_state) {
1985 return false;
1986 }
1988 const char* Deoptimization::trap_reason_name(int reason) {
1989 return "unknown";
1990 }
1992 void Deoptimization::print_statistics() {
1993 // no output
1994 }
1996 void
1997 Deoptimization::update_method_data_from_interpreter(MethodData* trap_mdo, int trap_bci, int reason) {
1998 // no udpate
1999 }
2001 int Deoptimization::trap_state_has_reason(int trap_state, int reason) {
2002 return 0;
2003 }
2005 void Deoptimization::gather_statistics(DeoptReason reason, DeoptAction action,
2006 Bytecodes::Code bc) {
2007 // no update
2008 }
2010 const char* Deoptimization::format_trap_state(char* buf, size_t buflen,
2011 int trap_state) {
2012 jio_snprintf(buf, buflen, "#%d", trap_state);
2013 return buf;
2014 }
2016 #endif // COMPILER2 || SHARK