src/share/vm/runtime/deoptimization.cpp

Tue, 09 Feb 2010 01:31:13 -0800

author
kvn
date
Tue, 09 Feb 2010 01:31:13 -0800
changeset 1688
f70b0d9ab095
parent 1641
87684f1a88b5
child 1690
e3a4305c6bc3
permissions
-rw-r--r--

6910618: C2: Error: assert(d->is_oop(),"JVM_ArrayCopy: dst not an oop")
Summary: Mark in PcDesc call sites which return oop and save the result oop across objects reallocation during deoptimization.
Reviewed-by: never

     1 /*
     2  * Copyright 1997-2010 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       assert (chunk->at(0)->scope() != NULL,"expect only compiled java frames");
   147       GrowableArray<ScopeValue*>* objects = chunk->at(0)->scope()->objects();
   149       // The flag return_oop() indicates call sites which return oop
   150       // in compiled code. Such sites include java method calls,
   151       // runtime calls (for example, used to allocate new objects/arrays
   152       // on slow code path) and any other calls generated in compiled code.
   153       // It is not guaranteed that we can get such information here only
   154       // by analyzing bytecode in deoptimized frames. This is why this flag
   155       // is set during method compilation (see Compile::Process_OopMap_Node()).
   156       bool save_oop_result = chunk->at(0)->scope()->return_oop();
   157       Handle return_value;
   158       if (save_oop_result) {
   159         // Reallocation may trigger GC. If deoptimization happened on return from
   160         // call which returns oop we need to save it since it is not in oopmap.
   161         oop result = deoptee.saved_oop_result(&map);
   162         assert(result == NULL || result->is_oop(), "must be oop");
   163         return_value = Handle(thread, result);
   164         assert(Universe::heap()->is_in_or_null(result), "must be heap pointer");
   165         if (TraceDeoptimization) {
   166           tty->print_cr("SAVED OOP RESULT " INTPTR_FORMAT " in thread " INTPTR_FORMAT, result, thread);
   167         }
   168       }
   169       bool reallocated = false;
   170       if (objects != NULL) {
   171         JRT_BLOCK
   172           reallocated = realloc_objects(thread, &deoptee, objects, THREAD);
   173         JRT_END
   174       }
   175       if (reallocated) {
   176         reassign_fields(&deoptee, &map, objects);
   177 #ifndef PRODUCT
   178         if (TraceDeoptimization) {
   179           ttyLocker ttyl;
   180           tty->print_cr("REALLOC OBJECTS in thread " INTPTR_FORMAT, thread);
   181           print_objects(objects);
   182         }
   183 #endif
   184       }
   185       if (save_oop_result) {
   186         // Restore result.
   187         deoptee.set_saved_oop_result(&map, return_value());
   188       }
   189     }
   190     if (EliminateLocks) {
   191 #ifndef PRODUCT
   192       bool first = true;
   193 #endif
   194       for (int i = 0; i < chunk->length(); i++) {
   195         compiledVFrame* cvf = chunk->at(i);
   196         assert (cvf->scope() != NULL,"expect only compiled java frames");
   197         GrowableArray<MonitorInfo*>* monitors = cvf->monitors();
   198         if (monitors->is_nonempty()) {
   199           relock_objects(monitors, thread);
   200 #ifndef PRODUCT
   201           if (TraceDeoptimization) {
   202             ttyLocker ttyl;
   203             for (int j = 0; j < monitors->length(); j++) {
   204               MonitorInfo* mi = monitors->at(j);
   205               if (mi->eliminated()) {
   206                 if (first) {
   207                   first = false;
   208                   tty->print_cr("RELOCK OBJECTS in thread " INTPTR_FORMAT, thread);
   209                 }
   210                 tty->print_cr("     object <" INTPTR_FORMAT "> locked", mi->owner());
   211               }
   212             }
   213           }
   214 #endif
   215         }
   216       }
   217     }
   218   }
   219 #endif // COMPILER2
   220   // Ensure that no safepoint is taken after pointers have been stored
   221   // in fields of rematerialized objects.  If a safepoint occurs from here on
   222   // out the java state residing in the vframeArray will be missed.
   223   No_Safepoint_Verifier no_safepoint;
   225   vframeArray* array = create_vframeArray(thread, deoptee, &map, chunk);
   227   assert(thread->vframe_array_head() == NULL, "Pending deopt!");;
   228   thread->set_vframe_array_head(array);
   230   // Now that the vframeArray has been created if we have any deferred local writes
   231   // added by jvmti then we can free up that structure as the data is now in the
   232   // vframeArray
   234   if (thread->deferred_locals() != NULL) {
   235     GrowableArray<jvmtiDeferredLocalVariableSet*>* list = thread->deferred_locals();
   236     int i = 0;
   237     do {
   238       // Because of inlining we could have multiple vframes for a single frame
   239       // and several of the vframes could have deferred writes. Find them all.
   240       if (list->at(i)->id() == array->original().id()) {
   241         jvmtiDeferredLocalVariableSet* dlv = list->at(i);
   242         list->remove_at(i);
   243         // individual jvmtiDeferredLocalVariableSet are CHeapObj's
   244         delete dlv;
   245       } else {
   246         i++;
   247       }
   248     } while ( i < list->length() );
   249     if (list->length() == 0) {
   250       thread->set_deferred_locals(NULL);
   251       // free the list and elements back to C heap.
   252       delete list;
   253     }
   255   }
   257   // Compute the caller frame based on the sender sp of stub_frame and stored frame sizes info.
   258   CodeBlob* cb = stub_frame.cb();
   259   // Verify we have the right vframeArray
   260   assert(cb->frame_size() >= 0, "Unexpected frame size");
   261   intptr_t* unpack_sp = stub_frame.sp() + cb->frame_size();
   263   // If the deopt call site is a MethodHandle invoke call site we have
   264   // to adjust the unpack_sp.
   265   nmethod* deoptee_nm = deoptee.cb()->as_nmethod_or_null();
   266   if (deoptee_nm != NULL && deoptee_nm->is_method_handle_return(deoptee.pc()))
   267     unpack_sp = deoptee.unextended_sp();
   269 #ifdef ASSERT
   270   assert(cb->is_deoptimization_stub() || cb->is_uncommon_trap_stub(), "just checking");
   271   Events::log("fetch unroll sp " INTPTR_FORMAT, unpack_sp);
   272 #endif
   273   // This is a guarantee instead of an assert because if vframe doesn't match
   274   // we will unpack the wrong deoptimized frame and wind up in strange places
   275   // where it will be very difficult to figure out what went wrong. Better
   276   // to die an early death here than some very obscure death later when the
   277   // trail is cold.
   278   // Note: on ia64 this guarantee can be fooled by frames with no memory stack
   279   // in that it will fail to detect a problem when there is one. This needs
   280   // more work in tiger timeframe.
   281   guarantee(array->unextended_sp() == unpack_sp, "vframe_array_head must contain the vframeArray to unpack");
   283   int number_of_frames = array->frames();
   285   // Compute the vframes' sizes.  Note that frame_sizes[] entries are ordered from outermost to innermost
   286   // virtual activation, which is the reverse of the elements in the vframes array.
   287   intptr_t* frame_sizes = NEW_C_HEAP_ARRAY(intptr_t, number_of_frames);
   288   // +1 because we always have an interpreter return address for the final slot.
   289   address* frame_pcs = NEW_C_HEAP_ARRAY(address, number_of_frames + 1);
   290   int callee_parameters = 0;
   291   int callee_locals = 0;
   292   int popframe_extra_args = 0;
   293   // Create an interpreter return address for the stub to use as its return
   294   // address so the skeletal frames are perfectly walkable
   295   frame_pcs[number_of_frames] = Interpreter::deopt_entry(vtos, 0);
   297   // PopFrame requires that the preserved incoming arguments from the recently-popped topmost
   298   // activation be put back on the expression stack of the caller for reexecution
   299   if (JvmtiExport::can_pop_frame() && thread->popframe_forcing_deopt_reexecution()) {
   300     popframe_extra_args = in_words(thread->popframe_preserved_args_size_in_words());
   301   }
   303   //
   304   // frame_sizes/frame_pcs[0] oldest frame (int or c2i)
   305   // frame_sizes/frame_pcs[1] next oldest frame (int)
   306   // frame_sizes/frame_pcs[n] youngest frame (int)
   307   //
   308   // Now a pc in frame_pcs is actually the return address to the frame's caller (a frame
   309   // owns the space for the return address to it's caller).  Confusing ain't it.
   310   //
   311   // The vframe array can address vframes with indices running from
   312   // 0.._frames-1. Index  0 is the youngest frame and _frame - 1 is the oldest (root) frame.
   313   // When we create the skeletal frames we need the oldest frame to be in the zero slot
   314   // in the frame_sizes/frame_pcs so the assembly code can do a trivial walk.
   315   // so things look a little strange in this loop.
   316   //
   317   for (int index = 0; index < array->frames(); index++ ) {
   318     // frame[number_of_frames - 1 ] = on_stack_size(youngest)
   319     // frame[number_of_frames - 2 ] = on_stack_size(sender(youngest))
   320     // frame[number_of_frames - 3 ] = on_stack_size(sender(sender(youngest)))
   321     frame_sizes[number_of_frames - 1 - index] = BytesPerWord * array->element(index)->on_stack_size(callee_parameters,
   322                                                                                                     callee_locals,
   323                                                                                                     index == 0,
   324                                                                                                     popframe_extra_args);
   325     // This pc doesn't have to be perfect just good enough to identify the frame
   326     // as interpreted so the skeleton frame will be walkable
   327     // The correct pc will be set when the skeleton frame is completely filled out
   328     // The final pc we store in the loop is wrong and will be overwritten below
   329     frame_pcs[number_of_frames - 1 - index ] = Interpreter::deopt_entry(vtos, 0) - frame::pc_return_offset;
   331     callee_parameters = array->element(index)->method()->size_of_parameters();
   332     callee_locals = array->element(index)->method()->max_locals();
   333     popframe_extra_args = 0;
   334   }
   336   // Compute whether the root vframe returns a float or double value.
   337   BasicType return_type;
   338   {
   339     HandleMark hm;
   340     methodHandle method(thread, array->element(0)->method());
   341     Bytecode_invoke* invoke = Bytecode_invoke_at_check(method, array->element(0)->bci());
   342     return_type = (invoke != NULL) ? invoke->result_type(thread) : T_ILLEGAL;
   343   }
   345   // Compute information for handling adapters and adjusting the frame size of the caller.
   346   int caller_adjustment = 0;
   348   // Find the current pc for sender of the deoptee. Since the sender may have been deoptimized
   349   // itself since the deoptee vframeArray was created we must get a fresh value of the pc rather
   350   // than simply use array->sender.pc(). This requires us to walk the current set of frames
   351   //
   352   frame deopt_sender = stub_frame.sender(&dummy_map); // First is the deoptee frame
   353   deopt_sender = deopt_sender.sender(&dummy_map);     // Now deoptee caller
   355   // Compute the amount the oldest interpreter frame will have to adjust
   356   // its caller's stack by. If the caller is a compiled frame then
   357   // we pretend that the callee has no parameters so that the
   358   // extension counts for the full amount of locals and not just
   359   // locals-parms. This is because without a c2i adapter the parm
   360   // area as created by the compiled frame will not be usable by
   361   // the interpreter. (Depending on the calling convention there
   362   // may not even be enough space).
   364   // QQQ I'd rather see this pushed down into last_frame_adjust
   365   // and have it take the sender (aka caller).
   367   if (deopt_sender.is_compiled_frame()) {
   368     caller_adjustment = last_frame_adjust(0, callee_locals);
   369   } else if (callee_locals > callee_parameters) {
   370     // The caller frame may need extending to accommodate
   371     // non-parameter locals of the first unpacked interpreted frame.
   372     // Compute that adjustment.
   373     caller_adjustment = last_frame_adjust(callee_parameters, callee_locals);
   374   }
   377   // If the sender is deoptimized the we must retrieve the address of the handler
   378   // since the frame will "magically" show the original pc before the deopt
   379   // and we'd undo the deopt.
   381   frame_pcs[0] = deopt_sender.raw_pc();
   383   assert(CodeCache::find_blob_unsafe(frame_pcs[0]) != NULL, "bad pc");
   385   UnrollBlock* info = new UnrollBlock(array->frame_size() * BytesPerWord,
   386                                       caller_adjustment * BytesPerWord,
   387                                       number_of_frames,
   388                                       frame_sizes,
   389                                       frame_pcs,
   390                                       return_type);
   391 #if defined(IA32) || defined(AMD64)
   392   // We need a way to pass fp to the unpacking code so the skeletal frames
   393   // come out correct. This is only needed for x86 because of c2 using ebp
   394   // as an allocatable register. So this update is useless (and harmless)
   395   // on the other platforms. It would be nice to do this in a different
   396   // way but even the old style deoptimization had a problem with deriving
   397   // this value. NEEDS_CLEANUP
   398   // Note: now that c1 is using c2's deopt blob we must do this on all
   399   // x86 based platforms
   400   intptr_t** fp_addr = (intptr_t**) (((address)info) + info->initial_fp_offset_in_bytes());
   401   *fp_addr = array->sender().fp(); // was adapter_caller
   402 #endif /* IA32 || AMD64 */
   404   if (array->frames() > 1) {
   405     if (VerifyStack && TraceDeoptimization) {
   406       tty->print_cr("Deoptimizing method containing inlining");
   407     }
   408   }
   410   array->set_unroll_block(info);
   411   return info;
   412 }
   414 // Called to cleanup deoptimization data structures in normal case
   415 // after unpacking to stack and when stack overflow error occurs
   416 void Deoptimization::cleanup_deopt_info(JavaThread *thread,
   417                                         vframeArray *array) {
   419   // Get array if coming from exception
   420   if (array == NULL) {
   421     array = thread->vframe_array_head();
   422   }
   423   thread->set_vframe_array_head(NULL);
   425   // Free the previous UnrollBlock
   426   vframeArray* old_array = thread->vframe_array_last();
   427   thread->set_vframe_array_last(array);
   429   if (old_array != NULL) {
   430     UnrollBlock* old_info = old_array->unroll_block();
   431     old_array->set_unroll_block(NULL);
   432     delete old_info;
   433     delete old_array;
   434   }
   436   // Deallocate any resource creating in this routine and any ResourceObjs allocated
   437   // inside the vframeArray (StackValueCollections)
   439   delete thread->deopt_mark();
   440   thread->set_deopt_mark(NULL);
   443   if (JvmtiExport::can_pop_frame()) {
   444 #ifndef CC_INTERP
   445     // Regardless of whether we entered this routine with the pending
   446     // popframe condition bit set, we should always clear it now
   447     thread->clear_popframe_condition();
   448 #else
   449     // C++ interpeter will clear has_pending_popframe when it enters
   450     // with method_resume. For deopt_resume2 we clear it now.
   451     if (thread->popframe_forcing_deopt_reexecution())
   452         thread->clear_popframe_condition();
   453 #endif /* CC_INTERP */
   454   }
   456   // unpack_frames() is called at the end of the deoptimization handler
   457   // and (in C2) at the end of the uncommon trap handler. Note this fact
   458   // so that an asynchronous stack walker can work again. This counter is
   459   // incremented at the beginning of fetch_unroll_info() and (in C2) at
   460   // the beginning of uncommon_trap().
   461   thread->dec_in_deopt_handler();
   462 }
   465 // Return BasicType of value being returned
   466 JRT_LEAF(BasicType, Deoptimization::unpack_frames(JavaThread* thread, int exec_mode))
   468   // We are already active int he special DeoptResourceMark any ResourceObj's we
   469   // allocate will be freed at the end of the routine.
   471   // It is actually ok to allocate handles in a leaf method. It causes no safepoints,
   472   // but makes the entry a little slower. There is however a little dance we have to
   473   // do in debug mode to get around the NoHandleMark code in the JRT_LEAF macro
   474   ResetNoHandleMark rnhm; // No-op in release/product versions
   475   HandleMark hm;
   477   frame stub_frame = thread->last_frame();
   479   // Since the frame to unpack is the top frame of this thread, the vframe_array_head
   480   // must point to the vframeArray for the unpack frame.
   481   vframeArray* array = thread->vframe_array_head();
   483 #ifndef PRODUCT
   484   if (TraceDeoptimization) {
   485     tty->print_cr("DEOPT UNPACKING thread " INTPTR_FORMAT " vframeArray " INTPTR_FORMAT " mode %d", thread, array, exec_mode);
   486   }
   487 #endif
   489   UnrollBlock* info = array->unroll_block();
   491   // Unpack the interpreter frames and any adapter frame (c2 only) we might create.
   492   array->unpack_to_stack(stub_frame, exec_mode);
   494   BasicType bt = info->return_type();
   496   // If we have an exception pending, claim that the return type is an oop
   497   // so the deopt_blob does not overwrite the exception_oop.
   499   if (exec_mode == Unpack_exception)
   500     bt = T_OBJECT;
   502   // Cleanup thread deopt data
   503   cleanup_deopt_info(thread, array);
   505 #ifndef PRODUCT
   506   if (VerifyStack) {
   507     ResourceMark res_mark;
   509     // Verify that the just-unpacked frames match the interpreter's
   510     // notions of expression stack and locals
   511     vframeArray* cur_array = thread->vframe_array_last();
   512     RegisterMap rm(thread, false);
   513     rm.set_include_argument_oops(false);
   514     bool is_top_frame = true;
   515     int callee_size_of_parameters = 0;
   516     int callee_max_locals = 0;
   517     for (int i = 0; i < cur_array->frames(); i++) {
   518       vframeArrayElement* el = cur_array->element(i);
   519       frame* iframe = el->iframe();
   520       guarantee(iframe->is_interpreted_frame(), "Wrong frame type");
   522       // Get the oop map for this bci
   523       InterpreterOopMap mask;
   524       int cur_invoke_parameter_size = 0;
   525       bool try_next_mask = false;
   526       int next_mask_expression_stack_size = -1;
   527       int top_frame_expression_stack_adjustment = 0;
   528       methodHandle mh(thread, iframe->interpreter_frame_method());
   529       OopMapCache::compute_one_oop_map(mh, iframe->interpreter_frame_bci(), &mask);
   530       BytecodeStream str(mh);
   531       str.set_start(iframe->interpreter_frame_bci());
   532       int max_bci = mh->code_size();
   533       // Get to the next bytecode if possible
   534       assert(str.bci() < max_bci, "bci in interpreter frame out of bounds");
   535       // Check to see if we can grab the number of outgoing arguments
   536       // at an uncommon trap for an invoke (where the compiler
   537       // generates debug info before the invoke has executed)
   538       Bytecodes::Code cur_code = str.next();
   539       if (cur_code == Bytecodes::_invokevirtual ||
   540           cur_code == Bytecodes::_invokespecial ||
   541           cur_code == Bytecodes::_invokestatic  ||
   542           cur_code == Bytecodes::_invokeinterface) {
   543         Bytecode_invoke* invoke = Bytecode_invoke_at(mh, iframe->interpreter_frame_bci());
   544         symbolHandle signature(thread, invoke->signature());
   545         ArgumentSizeComputer asc(signature);
   546         cur_invoke_parameter_size = asc.size();
   547         if (cur_code != Bytecodes::_invokestatic) {
   548           // Add in receiver
   549           ++cur_invoke_parameter_size;
   550         }
   551       }
   552       if (str.bci() < max_bci) {
   553         Bytecodes::Code bc = str.next();
   554         if (bc >= 0) {
   555           // The interpreter oop map generator reports results before
   556           // the current bytecode has executed except in the case of
   557           // calls. It seems to be hard to tell whether the compiler
   558           // has emitted debug information matching the "state before"
   559           // a given bytecode or the state after, so we try both
   560           switch (cur_code) {
   561             case Bytecodes::_invokevirtual:
   562             case Bytecodes::_invokespecial:
   563             case Bytecodes::_invokestatic:
   564             case Bytecodes::_invokeinterface:
   565             case Bytecodes::_athrow:
   566               break;
   567             default: {
   568               InterpreterOopMap next_mask;
   569               OopMapCache::compute_one_oop_map(mh, str.bci(), &next_mask);
   570               next_mask_expression_stack_size = next_mask.expression_stack_size();
   571               // Need to subtract off the size of the result type of
   572               // the bytecode because this is not described in the
   573               // debug info but returned to the interpreter in the TOS
   574               // caching register
   575               BasicType bytecode_result_type = Bytecodes::result_type(cur_code);
   576               if (bytecode_result_type != T_ILLEGAL) {
   577                 top_frame_expression_stack_adjustment = type2size[bytecode_result_type];
   578               }
   579               assert(top_frame_expression_stack_adjustment >= 0, "");
   580               try_next_mask = true;
   581               break;
   582             }
   583           }
   584         }
   585       }
   587       // Verify stack depth and oops in frame
   588       // This assertion may be dependent on the platform we're running on and may need modification (tested on x86 and sparc)
   589       if (!(
   590             /* SPARC */
   591             (iframe->interpreter_frame_expression_stack_size() == mask.expression_stack_size() + callee_size_of_parameters) ||
   592             /* x86 */
   593             (iframe->interpreter_frame_expression_stack_size() == mask.expression_stack_size() + callee_max_locals) ||
   594             (try_next_mask &&
   595              (iframe->interpreter_frame_expression_stack_size() == (next_mask_expression_stack_size -
   596                                                                     top_frame_expression_stack_adjustment))) ||
   597             (is_top_frame && (exec_mode == Unpack_exception) && iframe->interpreter_frame_expression_stack_size() == 0) ||
   598             (is_top_frame && (exec_mode == Unpack_uncommon_trap || exec_mode == Unpack_reexecute) &&
   599              (iframe->interpreter_frame_expression_stack_size() == mask.expression_stack_size() + cur_invoke_parameter_size))
   600             )) {
   601         ttyLocker ttyl;
   603         // Print out some information that will help us debug the problem
   604         tty->print_cr("Wrong number of expression stack elements during deoptimization");
   605         tty->print_cr("  Error occurred while verifying frame %d (0..%d, 0 is topmost)", i, cur_array->frames() - 1);
   606         tty->print_cr("  Fabricated interpreter frame had %d expression stack elements",
   607                       iframe->interpreter_frame_expression_stack_size());
   608         tty->print_cr("  Interpreter oop map had %d expression stack elements", mask.expression_stack_size());
   609         tty->print_cr("  try_next_mask = %d", try_next_mask);
   610         tty->print_cr("  next_mask_expression_stack_size = %d", next_mask_expression_stack_size);
   611         tty->print_cr("  callee_size_of_parameters = %d", callee_size_of_parameters);
   612         tty->print_cr("  callee_max_locals = %d", callee_max_locals);
   613         tty->print_cr("  top_frame_expression_stack_adjustment = %d", top_frame_expression_stack_adjustment);
   614         tty->print_cr("  exec_mode = %d", exec_mode);
   615         tty->print_cr("  cur_invoke_parameter_size = %d", cur_invoke_parameter_size);
   616         tty->print_cr("  Thread = " INTPTR_FORMAT ", thread ID = " UINTX_FORMAT, thread, thread->osthread()->thread_id());
   617         tty->print_cr("  Interpreted frames:");
   618         for (int k = 0; k < cur_array->frames(); k++) {
   619           vframeArrayElement* el = cur_array->element(k);
   620           tty->print_cr("    %s (bci %d)", el->method()->name_and_sig_as_C_string(), el->bci());
   621         }
   622         cur_array->print_on_2(tty);
   623         guarantee(false, "wrong number of expression stack elements during deopt");
   624       }
   625       VerifyOopClosure verify;
   626       iframe->oops_interpreted_do(&verify, &rm, false);
   627       callee_size_of_parameters = mh->size_of_parameters();
   628       callee_max_locals = mh->max_locals();
   629       is_top_frame = false;
   630     }
   631   }
   632 #endif /* !PRODUCT */
   635   return bt;
   636 JRT_END
   639 int Deoptimization::deoptimize_dependents() {
   640   Threads::deoptimized_wrt_marked_nmethods();
   641   return 0;
   642 }
   645 #ifdef COMPILER2
   646 bool Deoptimization::realloc_objects(JavaThread* thread, frame* fr, GrowableArray<ScopeValue*>* objects, TRAPS) {
   647   Handle pending_exception(thread->pending_exception());
   648   const char* exception_file = thread->exception_file();
   649   int exception_line = thread->exception_line();
   650   thread->clear_pending_exception();
   652   for (int i = 0; i < objects->length(); i++) {
   653     assert(objects->at(i)->is_object(), "invalid debug information");
   654     ObjectValue* sv = (ObjectValue*) objects->at(i);
   656     KlassHandle k(((ConstantOopReadValue*) sv->klass())->value()());
   657     oop obj = NULL;
   659     if (k->oop_is_instance()) {
   660       instanceKlass* ik = instanceKlass::cast(k());
   661       obj = ik->allocate_instance(CHECK_(false));
   662     } else if (k->oop_is_typeArray()) {
   663       typeArrayKlass* ak = typeArrayKlass::cast(k());
   664       assert(sv->field_size() % type2size[ak->element_type()] == 0, "non-integral array length");
   665       int len = sv->field_size() / type2size[ak->element_type()];
   666       obj = ak->allocate(len, CHECK_(false));
   667     } else if (k->oop_is_objArray()) {
   668       objArrayKlass* ak = objArrayKlass::cast(k());
   669       obj = ak->allocate(sv->field_size(), CHECK_(false));
   670     }
   672     assert(obj != NULL, "allocation failed");
   673     assert(sv->value().is_null(), "redundant reallocation");
   674     sv->set_value(obj);
   675   }
   677   if (pending_exception.not_null()) {
   678     thread->set_pending_exception(pending_exception(), exception_file, exception_line);
   679   }
   681   return true;
   682 }
   684 // This assumes that the fields are stored in ObjectValue in the same order
   685 // they are yielded by do_nonstatic_fields.
   686 class FieldReassigner: public FieldClosure {
   687   frame* _fr;
   688   RegisterMap* _reg_map;
   689   ObjectValue* _sv;
   690   instanceKlass* _ik;
   691   oop _obj;
   693   int _i;
   694 public:
   695   FieldReassigner(frame* fr, RegisterMap* reg_map, ObjectValue* sv, oop obj) :
   696     _fr(fr), _reg_map(reg_map), _sv(sv), _obj(obj), _i(0) {}
   698   int i() const { return _i; }
   701   void do_field(fieldDescriptor* fd) {
   702     intptr_t val;
   703     StackValue* value =
   704       StackValue::create_stack_value(_fr, _reg_map, _sv->field_at(i()));
   705     int offset = fd->offset();
   706     switch (fd->field_type()) {
   707     case T_OBJECT: case T_ARRAY:
   708       assert(value->type() == T_OBJECT, "Agreement.");
   709       _obj->obj_field_put(offset, value->get_obj()());
   710       break;
   712     case T_LONG: case T_DOUBLE: {
   713       assert(value->type() == T_INT, "Agreement.");
   714       StackValue* low =
   715         StackValue::create_stack_value(_fr, _reg_map, _sv->field_at(++_i));
   716 #ifdef _LP64
   717       jlong res = (jlong)low->get_int();
   718 #else
   719 #ifdef SPARC
   720       // For SPARC we have to swap high and low words.
   721       jlong res = jlong_from((jint)low->get_int(), (jint)value->get_int());
   722 #else
   723       jlong res = jlong_from((jint)value->get_int(), (jint)low->get_int());
   724 #endif //SPARC
   725 #endif
   726       _obj->long_field_put(offset, res);
   727       break;
   728     }
   729     // Have to cast to INT (32 bits) pointer to avoid little/big-endian problem.
   730     case T_INT: case T_FLOAT: // 4 bytes.
   731       assert(value->type() == T_INT, "Agreement.");
   732       val = value->get_int();
   733       _obj->int_field_put(offset, (jint)*((jint*)&val));
   734       break;
   736     case T_SHORT: case T_CHAR: // 2 bytes
   737       assert(value->type() == T_INT, "Agreement.");
   738       val = value->get_int();
   739       _obj->short_field_put(offset, (jshort)*((jint*)&val));
   740       break;
   742     case T_BOOLEAN: case T_BYTE: // 1 byte
   743       assert(value->type() == T_INT, "Agreement.");
   744       val = value->get_int();
   745       _obj->bool_field_put(offset, (jboolean)*((jint*)&val));
   746       break;
   748     default:
   749       ShouldNotReachHere();
   750     }
   751     _i++;
   752   }
   753 };
   755 // restore elements of an eliminated type array
   756 void Deoptimization::reassign_type_array_elements(frame* fr, RegisterMap* reg_map, ObjectValue* sv, typeArrayOop obj, BasicType type) {
   757   int index = 0;
   758   intptr_t val;
   760   for (int i = 0; i < sv->field_size(); i++) {
   761     StackValue* value = StackValue::create_stack_value(fr, reg_map, sv->field_at(i));
   762     switch(type) {
   763     case T_LONG: case T_DOUBLE: {
   764       assert(value->type() == T_INT, "Agreement.");
   765       StackValue* low =
   766         StackValue::create_stack_value(fr, reg_map, sv->field_at(++i));
   767 #ifdef _LP64
   768       jlong res = (jlong)low->get_int();
   769 #else
   770 #ifdef SPARC
   771       // For SPARC we have to swap high and low words.
   772       jlong res = jlong_from((jint)low->get_int(), (jint)value->get_int());
   773 #else
   774       jlong res = jlong_from((jint)value->get_int(), (jint)low->get_int());
   775 #endif //SPARC
   776 #endif
   777       obj->long_at_put(index, res);
   778       break;
   779     }
   781     // Have to cast to INT (32 bits) pointer to avoid little/big-endian problem.
   782     case T_INT: case T_FLOAT: // 4 bytes.
   783       assert(value->type() == T_INT, "Agreement.");
   784       val = value->get_int();
   785       obj->int_at_put(index, (jint)*((jint*)&val));
   786       break;
   788     case T_SHORT: case T_CHAR: // 2 bytes
   789       assert(value->type() == T_INT, "Agreement.");
   790       val = value->get_int();
   791       obj->short_at_put(index, (jshort)*((jint*)&val));
   792       break;
   794     case T_BOOLEAN: case T_BYTE: // 1 byte
   795       assert(value->type() == T_INT, "Agreement.");
   796       val = value->get_int();
   797       obj->bool_at_put(index, (jboolean)*((jint*)&val));
   798       break;
   800       default:
   801         ShouldNotReachHere();
   802     }
   803     index++;
   804   }
   805 }
   808 // restore fields of an eliminated object array
   809 void Deoptimization::reassign_object_array_elements(frame* fr, RegisterMap* reg_map, ObjectValue* sv, objArrayOop obj) {
   810   for (int i = 0; i < sv->field_size(); i++) {
   811     StackValue* value = StackValue::create_stack_value(fr, reg_map, sv->field_at(i));
   812     assert(value->type() == T_OBJECT, "object element expected");
   813     obj->obj_at_put(i, value->get_obj()());
   814   }
   815 }
   818 // restore fields of all eliminated objects and arrays
   819 void Deoptimization::reassign_fields(frame* fr, RegisterMap* reg_map, GrowableArray<ScopeValue*>* objects) {
   820   for (int i = 0; i < objects->length(); i++) {
   821     ObjectValue* sv = (ObjectValue*) objects->at(i);
   822     KlassHandle k(((ConstantOopReadValue*) sv->klass())->value()());
   823     Handle obj = sv->value();
   824     assert(obj.not_null(), "reallocation was missed");
   826     if (k->oop_is_instance()) {
   827       instanceKlass* ik = instanceKlass::cast(k());
   828       FieldReassigner reassign(fr, reg_map, sv, obj());
   829       ik->do_nonstatic_fields(&reassign);
   830     } else if (k->oop_is_typeArray()) {
   831       typeArrayKlass* ak = typeArrayKlass::cast(k());
   832       reassign_type_array_elements(fr, reg_map, sv, (typeArrayOop) obj(), ak->element_type());
   833     } else if (k->oop_is_objArray()) {
   834       reassign_object_array_elements(fr, reg_map, sv, (objArrayOop) obj());
   835     }
   836   }
   837 }
   840 // relock objects for which synchronization was eliminated
   841 void Deoptimization::relock_objects(GrowableArray<MonitorInfo*>* monitors, JavaThread* thread) {
   842   for (int i = 0; i < monitors->length(); i++) {
   843     MonitorInfo* mon_info = monitors->at(i);
   844     if (mon_info->eliminated()) {
   845       assert(mon_info->owner() != NULL, "reallocation was missed");
   846       Handle obj = Handle(mon_info->owner());
   847       markOop mark = obj->mark();
   848       if (UseBiasedLocking && mark->has_bias_pattern()) {
   849         // New allocated objects may have the mark set to anonymously biased.
   850         // Also the deoptimized method may called methods with synchronization
   851         // where the thread-local object is bias locked to the current thread.
   852         assert(mark->is_biased_anonymously() ||
   853                mark->biased_locker() == thread, "should be locked to current thread");
   854         // Reset mark word to unbiased prototype.
   855         markOop unbiased_prototype = markOopDesc::prototype()->set_age(mark->age());
   856         obj->set_mark(unbiased_prototype);
   857       }
   858       BasicLock* lock = mon_info->lock();
   859       ObjectSynchronizer::slow_enter(obj, lock, thread);
   860     }
   861     assert(mon_info->owner()->is_locked(), "object must be locked now");
   862   }
   863 }
   866 #ifndef PRODUCT
   867 // print information about reallocated objects
   868 void Deoptimization::print_objects(GrowableArray<ScopeValue*>* objects) {
   869   fieldDescriptor fd;
   871   for (int i = 0; i < objects->length(); i++) {
   872     ObjectValue* sv = (ObjectValue*) objects->at(i);
   873     KlassHandle k(((ConstantOopReadValue*) sv->klass())->value()());
   874     Handle obj = sv->value();
   876     tty->print("     object <" INTPTR_FORMAT "> of type ", sv->value()());
   877     k->as_klassOop()->print_value();
   878     tty->print(" allocated (%d bytes)", obj->size() * HeapWordSize);
   879     tty->cr();
   881     if (Verbose) {
   882       k->oop_print_on(obj(), tty);
   883     }
   884   }
   885 }
   886 #endif
   887 #endif // COMPILER2
   889 vframeArray* Deoptimization::create_vframeArray(JavaThread* thread, frame fr, RegisterMap *reg_map, GrowableArray<compiledVFrame*>* chunk) {
   891 #ifndef PRODUCT
   892   if (TraceDeoptimization) {
   893     ttyLocker ttyl;
   894     tty->print("DEOPT PACKING thread " INTPTR_FORMAT " ", thread);
   895     fr.print_on(tty);
   896     tty->print_cr("     Virtual frames (innermost first):");
   897     for (int index = 0; index < chunk->length(); index++) {
   898       compiledVFrame* vf = chunk->at(index);
   899       tty->print("       %2d - ", index);
   900       vf->print_value();
   901       int bci = chunk->at(index)->raw_bci();
   902       const char* code_name;
   903       if (bci == SynchronizationEntryBCI) {
   904         code_name = "sync entry";
   905       } else {
   906         Bytecodes::Code code = Bytecodes::code_at(vf->method(), bci);
   907         code_name = Bytecodes::name(code);
   908       }
   909       tty->print(" - %s", code_name);
   910       tty->print_cr(" @ bci %d ", bci);
   911       if (Verbose) {
   912         vf->print();
   913         tty->cr();
   914       }
   915     }
   916   }
   917 #endif
   919   // Register map for next frame (used for stack crawl).  We capture
   920   // the state of the deopt'ing frame's caller.  Thus if we need to
   921   // stuff a C2I adapter we can properly fill in the callee-save
   922   // register locations.
   923   frame caller = fr.sender(reg_map);
   924   int frame_size = caller.sp() - fr.sp();
   926   frame sender = caller;
   928   // Since the Java thread being deoptimized will eventually adjust it's own stack,
   929   // the vframeArray containing the unpacking information is allocated in the C heap.
   930   // For Compiler1, the caller of the deoptimized frame is saved for use by unpack_frames().
   931   vframeArray* array = vframeArray::allocate(thread, frame_size, chunk, reg_map, sender, caller, fr);
   933   // Compare the vframeArray to the collected vframes
   934   assert(array->structural_compare(thread, chunk), "just checking");
   935   Events::log("# vframes = %d", (intptr_t)chunk->length());
   937 #ifndef PRODUCT
   938   if (TraceDeoptimization) {
   939     ttyLocker ttyl;
   940     tty->print_cr("     Created vframeArray " INTPTR_FORMAT, array);
   941     if (Verbose) {
   942       int count = 0;
   943       // this used to leak deoptimizedVFrame like it was going out of style!!!
   944       for (int index = 0; index < array->frames(); index++ ) {
   945         vframeArrayElement* e = array->element(index);
   946         e->print(tty);
   948         /*
   949           No printing yet.
   950         array->vframe_at(index)->print_activation(count++);
   951         // better as...
   952         array->print_activation_for(index, count++);
   953         */
   954       }
   955     }
   956   }
   957 #endif // PRODUCT
   959   return array;
   960 }
   963 static void collect_monitors(compiledVFrame* cvf, GrowableArray<Handle>* objects_to_revoke) {
   964   GrowableArray<MonitorInfo*>* monitors = cvf->monitors();
   965   for (int i = 0; i < monitors->length(); i++) {
   966     MonitorInfo* mon_info = monitors->at(i);
   967     if (!mon_info->eliminated() && mon_info->owner() != NULL) {
   968       objects_to_revoke->append(Handle(mon_info->owner()));
   969     }
   970   }
   971 }
   974 void Deoptimization::revoke_biases_of_monitors(JavaThread* thread, frame fr, RegisterMap* map) {
   975   if (!UseBiasedLocking) {
   976     return;
   977   }
   979   GrowableArray<Handle>* objects_to_revoke = new GrowableArray<Handle>();
   981   // Unfortunately we don't have a RegisterMap available in most of
   982   // the places we want to call this routine so we need to walk the
   983   // stack again to update the register map.
   984   if (map == NULL || !map->update_map()) {
   985     StackFrameStream sfs(thread, true);
   986     bool found = false;
   987     while (!found && !sfs.is_done()) {
   988       frame* cur = sfs.current();
   989       sfs.next();
   990       found = cur->id() == fr.id();
   991     }
   992     assert(found, "frame to be deoptimized not found on target thread's stack");
   993     map = sfs.register_map();
   994   }
   996   vframe* vf = vframe::new_vframe(&fr, map, thread);
   997   compiledVFrame* cvf = compiledVFrame::cast(vf);
   998   // Revoke monitors' biases in all scopes
   999   while (!cvf->is_top()) {
  1000     collect_monitors(cvf, objects_to_revoke);
  1001     cvf = compiledVFrame::cast(cvf->sender());
  1003   collect_monitors(cvf, objects_to_revoke);
  1005   if (SafepointSynchronize::is_at_safepoint()) {
  1006     BiasedLocking::revoke_at_safepoint(objects_to_revoke);
  1007   } else {
  1008     BiasedLocking::revoke(objects_to_revoke);
  1013 void Deoptimization::revoke_biases_of_monitors(CodeBlob* cb) {
  1014   if (!UseBiasedLocking) {
  1015     return;
  1018   assert(SafepointSynchronize::is_at_safepoint(), "must only be called from safepoint");
  1019   GrowableArray<Handle>* objects_to_revoke = new GrowableArray<Handle>();
  1020   for (JavaThread* jt = Threads::first(); jt != NULL ; jt = jt->next()) {
  1021     if (jt->has_last_Java_frame()) {
  1022       StackFrameStream sfs(jt, true);
  1023       while (!sfs.is_done()) {
  1024         frame* cur = sfs.current();
  1025         if (cb->contains(cur->pc())) {
  1026           vframe* vf = vframe::new_vframe(cur, sfs.register_map(), jt);
  1027           compiledVFrame* cvf = compiledVFrame::cast(vf);
  1028           // Revoke monitors' biases in all scopes
  1029           while (!cvf->is_top()) {
  1030             collect_monitors(cvf, objects_to_revoke);
  1031             cvf = compiledVFrame::cast(cvf->sender());
  1033           collect_monitors(cvf, objects_to_revoke);
  1035         sfs.next();
  1039   BiasedLocking::revoke_at_safepoint(objects_to_revoke);
  1043 void Deoptimization::deoptimize_single_frame(JavaThread* thread, frame fr) {
  1044   assert(fr.can_be_deoptimized(), "checking frame type");
  1046   gather_statistics(Reason_constraint, Action_none, Bytecodes::_illegal);
  1048   EventMark m("Deoptimization (pc=" INTPTR_FORMAT ", sp=" INTPTR_FORMAT ")", fr.pc(), fr.id());
  1050   // Patch the nmethod so that when execution returns to it we will
  1051   // deopt the execution state and return to the interpreter.
  1052   fr.deoptimize(thread);
  1055 void Deoptimization::deoptimize(JavaThread* thread, frame fr, RegisterMap *map) {
  1056   // Deoptimize only if the frame comes from compile code.
  1057   // Do not deoptimize the frame which is already patched
  1058   // during the execution of the loops below.
  1059   if (!fr.is_compiled_frame() || fr.is_deoptimized_frame()) {
  1060     return;
  1062   ResourceMark rm;
  1063   DeoptimizationMarker dm;
  1064   if (UseBiasedLocking) {
  1065     revoke_biases_of_monitors(thread, fr, map);
  1067   deoptimize_single_frame(thread, fr);
  1072 void Deoptimization::deoptimize_frame(JavaThread* thread, intptr_t* id) {
  1073   // Compute frame and register map based on thread and sp.
  1074   RegisterMap reg_map(thread, UseBiasedLocking);
  1075   frame fr = thread->last_frame();
  1076   while (fr.id() != id) {
  1077     fr = fr.sender(&reg_map);
  1079   deoptimize(thread, fr, &reg_map);
  1083 // JVMTI PopFrame support
  1084 JRT_LEAF(void, Deoptimization::popframe_preserve_args(JavaThread* thread, int bytes_to_save, void* start_address))
  1086   thread->popframe_preserve_args(in_ByteSize(bytes_to_save), start_address);
  1088 JRT_END
  1091 #ifdef COMPILER2
  1092 void Deoptimization::load_class_by_index(constantPoolHandle constant_pool, int index, TRAPS) {
  1093   // in case of an unresolved klass entry, load the class.
  1094   if (constant_pool->tag_at(index).is_unresolved_klass()) {
  1095     klassOop tk = constant_pool->klass_at(index, CHECK);
  1096     return;
  1099   if (!constant_pool->tag_at(index).is_symbol()) return;
  1101   Handle class_loader (THREAD, instanceKlass::cast(constant_pool->pool_holder())->class_loader());
  1102   symbolHandle symbol (THREAD, constant_pool->symbol_at(index));
  1104   // class name?
  1105   if (symbol->byte_at(0) != '(') {
  1106     Handle protection_domain (THREAD, Klass::cast(constant_pool->pool_holder())->protection_domain());
  1107     SystemDictionary::resolve_or_null(symbol, class_loader, protection_domain, CHECK);
  1108     return;
  1111   // then it must be a signature!
  1112   for (SignatureStream ss(symbol); !ss.is_done(); ss.next()) {
  1113     if (ss.is_object()) {
  1114       symbolOop s = ss.as_symbol(CHECK);
  1115       symbolHandle class_name (THREAD, s);
  1116       Handle protection_domain (THREAD, Klass::cast(constant_pool->pool_holder())->protection_domain());
  1117       SystemDictionary::resolve_or_null(class_name, class_loader, protection_domain, CHECK);
  1123 void Deoptimization::load_class_by_index(constantPoolHandle constant_pool, int index) {
  1124   EXCEPTION_MARK;
  1125   load_class_by_index(constant_pool, index, THREAD);
  1126   if (HAS_PENDING_EXCEPTION) {
  1127     // Exception happened during classloading. We ignore the exception here, since it
  1128     // is going to be rethrown since the current activation is going to be deoptimzied and
  1129     // the interpreter will re-execute the bytecode.
  1130     CLEAR_PENDING_EXCEPTION;
  1134 JRT_ENTRY(void, Deoptimization::uncommon_trap_inner(JavaThread* thread, jint trap_request)) {
  1135   HandleMark hm;
  1137   // uncommon_trap() is called at the beginning of the uncommon trap
  1138   // handler. Note this fact before we start generating temporary frames
  1139   // that can confuse an asynchronous stack walker. This counter is
  1140   // decremented at the end of unpack_frames().
  1141   thread->inc_in_deopt_handler();
  1143   // We need to update the map if we have biased locking.
  1144   RegisterMap reg_map(thread, UseBiasedLocking);
  1145   frame stub_frame = thread->last_frame();
  1146   frame fr = stub_frame.sender(&reg_map);
  1147   // Make sure the calling nmethod is not getting deoptimized and removed
  1148   // before we are done with it.
  1149   nmethodLocker nl(fr.pc());
  1152     ResourceMark rm;
  1154     // Revoke biases of any monitors in the frame to ensure we can migrate them
  1155     revoke_biases_of_monitors(thread, fr, &reg_map);
  1157     DeoptReason reason = trap_request_reason(trap_request);
  1158     DeoptAction action = trap_request_action(trap_request);
  1159     jint unloaded_class_index = trap_request_index(trap_request); // CP idx or -1
  1161     Events::log("Uncommon trap occurred @" INTPTR_FORMAT " unloaded_class_index = %d", fr.pc(), (int) trap_request);
  1162     vframe*  vf  = vframe::new_vframe(&fr, &reg_map, thread);
  1163     compiledVFrame* cvf = compiledVFrame::cast(vf);
  1165     nmethod* nm = cvf->code();
  1167     ScopeDesc*      trap_scope  = cvf->scope();
  1168     methodHandle    trap_method = trap_scope->method();
  1169     int             trap_bci    = trap_scope->bci();
  1170     Bytecodes::Code trap_bc     = Bytecode_at(trap_method->bcp_from(trap_bci))->java_code();
  1172     // Record this event in the histogram.
  1173     gather_statistics(reason, action, trap_bc);
  1175     // Ensure that we can record deopt. history:
  1176     bool create_if_missing = ProfileTraps;
  1178     methodDataHandle trap_mdo
  1179       (THREAD, get_method_data(thread, trap_method, create_if_missing));
  1181     // Print a bunch of diagnostics, if requested.
  1182     if (TraceDeoptimization || LogCompilation) {
  1183       ResourceMark rm;
  1184       ttyLocker ttyl;
  1185       char buf[100];
  1186       if (xtty != NULL) {
  1187         xtty->begin_head("uncommon_trap thread='" UINTX_FORMAT"' %s",
  1188                          os::current_thread_id(),
  1189                          format_trap_request(buf, sizeof(buf), trap_request));
  1190         nm->log_identity(xtty);
  1192       symbolHandle class_name;
  1193       bool unresolved = false;
  1194       if (unloaded_class_index >= 0) {
  1195         constantPoolHandle constants (THREAD, trap_method->constants());
  1196         if (constants->tag_at(unloaded_class_index).is_unresolved_klass()) {
  1197           class_name = symbolHandle(THREAD,
  1198             constants->klass_name_at(unloaded_class_index));
  1199           unresolved = true;
  1200           if (xtty != NULL)
  1201             xtty->print(" unresolved='1'");
  1202         } else if (constants->tag_at(unloaded_class_index).is_symbol()) {
  1203           class_name = symbolHandle(THREAD,
  1204             constants->symbol_at(unloaded_class_index));
  1206         if (xtty != NULL)
  1207           xtty->name(class_name);
  1209       if (xtty != NULL && trap_mdo.not_null()) {
  1210         // Dump the relevant MDO state.
  1211         // This is the deopt count for the current reason, any previous
  1212         // reasons or recompiles seen at this point.
  1213         int dcnt = trap_mdo->trap_count(reason);
  1214         if (dcnt != 0)
  1215           xtty->print(" count='%d'", dcnt);
  1216         ProfileData* pdata = trap_mdo->bci_to_data(trap_bci);
  1217         int dos = (pdata == NULL)? 0: pdata->trap_state();
  1218         if (dos != 0) {
  1219           xtty->print(" state='%s'", format_trap_state(buf, sizeof(buf), dos));
  1220           if (trap_state_is_recompiled(dos)) {
  1221             int recnt2 = trap_mdo->overflow_recompile_count();
  1222             if (recnt2 != 0)
  1223               xtty->print(" recompiles2='%d'", recnt2);
  1227       if (xtty != NULL) {
  1228         xtty->stamp();
  1229         xtty->end_head();
  1231       if (TraceDeoptimization) {  // make noise on the tty
  1232         tty->print("Uncommon trap occurred in");
  1233         nm->method()->print_short_name(tty);
  1234         tty->print(" (@" INTPTR_FORMAT ") thread=%d reason=%s action=%s unloaded_class_index=%d",
  1235                    fr.pc(),
  1236                    (int) os::current_thread_id(),
  1237                    trap_reason_name(reason),
  1238                    trap_action_name(action),
  1239                    unloaded_class_index);
  1240         if (class_name.not_null()) {
  1241           tty->print(unresolved ? " unresolved class: " : " symbol: ");
  1242           class_name->print_symbol_on(tty);
  1244         tty->cr();
  1246       if (xtty != NULL) {
  1247         // Log the precise location of the trap.
  1248         for (ScopeDesc* sd = trap_scope; ; sd = sd->sender()) {
  1249           xtty->begin_elem("jvms bci='%d'", sd->bci());
  1250           xtty->method(sd->method());
  1251           xtty->end_elem();
  1252           if (sd->is_top())  break;
  1254         xtty->tail("uncommon_trap");
  1257     // (End diagnostic printout.)
  1259     // Load class if necessary
  1260     if (unloaded_class_index >= 0) {
  1261       constantPoolHandle constants(THREAD, trap_method->constants());
  1262       load_class_by_index(constants, unloaded_class_index);
  1265     // Flush the nmethod if necessary and desirable.
  1266     //
  1267     // We need to avoid situations where we are re-flushing the nmethod
  1268     // because of a hot deoptimization site.  Repeated flushes at the same
  1269     // point need to be detected by the compiler and avoided.  If the compiler
  1270     // cannot avoid them (or has a bug and "refuses" to avoid them), this
  1271     // module must take measures to avoid an infinite cycle of recompilation
  1272     // and deoptimization.  There are several such measures:
  1273     //
  1274     //   1. If a recompilation is ordered a second time at some site X
  1275     //   and for the same reason R, the action is adjusted to 'reinterpret',
  1276     //   to give the interpreter time to exercise the method more thoroughly.
  1277     //   If this happens, the method's overflow_recompile_count is incremented.
  1278     //
  1279     //   2. If the compiler fails to reduce the deoptimization rate, then
  1280     //   the method's overflow_recompile_count will begin to exceed the set
  1281     //   limit PerBytecodeRecompilationCutoff.  If this happens, the action
  1282     //   is adjusted to 'make_not_compilable', and the method is abandoned
  1283     //   to the interpreter.  This is a performance hit for hot methods,
  1284     //   but is better than a disastrous infinite cycle of recompilations.
  1285     //   (Actually, only the method containing the site X is abandoned.)
  1286     //
  1287     //   3. In parallel with the previous measures, if the total number of
  1288     //   recompilations of a method exceeds the much larger set limit
  1289     //   PerMethodRecompilationCutoff, the method is abandoned.
  1290     //   This should only happen if the method is very large and has
  1291     //   many "lukewarm" deoptimizations.  The code which enforces this
  1292     //   limit is elsewhere (class nmethod, class methodOopDesc).
  1293     //
  1294     // Note that the per-BCI 'is_recompiled' bit gives the compiler one chance
  1295     // to recompile at each bytecode independently of the per-BCI cutoff.
  1296     //
  1297     // The decision to update code is up to the compiler, and is encoded
  1298     // in the Action_xxx code.  If the compiler requests Action_none
  1299     // no trap state is changed, no compiled code is changed, and the
  1300     // computation suffers along in the interpreter.
  1301     //
  1302     // The other action codes specify various tactics for decompilation
  1303     // and recompilation.  Action_maybe_recompile is the loosest, and
  1304     // allows the compiled code to stay around until enough traps are seen,
  1305     // and until the compiler gets around to recompiling the trapping method.
  1306     //
  1307     // The other actions cause immediate removal of the present code.
  1309     bool update_trap_state = true;
  1310     bool make_not_entrant = false;
  1311     bool make_not_compilable = false;
  1312     bool reset_counters = false;
  1313     switch (action) {
  1314     case Action_none:
  1315       // Keep the old code.
  1316       update_trap_state = false;
  1317       break;
  1318     case Action_maybe_recompile:
  1319       // Do not need to invalidate the present code, but we can
  1320       // initiate another
  1321       // Start compiler without (necessarily) invalidating the nmethod.
  1322       // The system will tolerate the old code, but new code should be
  1323       // generated when possible.
  1324       break;
  1325     case Action_reinterpret:
  1326       // Go back into the interpreter for a while, and then consider
  1327       // recompiling form scratch.
  1328       make_not_entrant = true;
  1329       // Reset invocation counter for outer most method.
  1330       // This will allow the interpreter to exercise the bytecodes
  1331       // for a while before recompiling.
  1332       // By contrast, Action_make_not_entrant is immediate.
  1333       //
  1334       // Note that the compiler will track null_check, null_assert,
  1335       // range_check, and class_check events and log them as if they
  1336       // had been traps taken from compiled code.  This will update
  1337       // the MDO trap history so that the next compilation will
  1338       // properly detect hot trap sites.
  1339       reset_counters = true;
  1340       break;
  1341     case Action_make_not_entrant:
  1342       // Request immediate recompilation, and get rid of the old code.
  1343       // Make them not entrant, so next time they are called they get
  1344       // recompiled.  Unloaded classes are loaded now so recompile before next
  1345       // time they are called.  Same for uninitialized.  The interpreter will
  1346       // link the missing class, if any.
  1347       make_not_entrant = true;
  1348       break;
  1349     case Action_make_not_compilable:
  1350       // Give up on compiling this method at all.
  1351       make_not_entrant = true;
  1352       make_not_compilable = true;
  1353       break;
  1354     default:
  1355       ShouldNotReachHere();
  1358     // Setting +ProfileTraps fixes the following, on all platforms:
  1359     // 4852688: ProfileInterpreter is off by default for ia64.  The result is
  1360     // infinite heroic-opt-uncommon-trap/deopt/recompile cycles, since the
  1361     // recompile relies on a methodDataOop to record heroic opt failures.
  1363     // Whether the interpreter is producing MDO data or not, we also need
  1364     // to use the MDO to detect hot deoptimization points and control
  1365     // aggressive optimization.
  1366     bool inc_recompile_count = false;
  1367     ProfileData* pdata = NULL;
  1368     if (ProfileTraps && update_trap_state && trap_mdo.not_null()) {
  1369       assert(trap_mdo() == get_method_data(thread, trap_method, false), "sanity");
  1370       uint this_trap_count = 0;
  1371       bool maybe_prior_trap = false;
  1372       bool maybe_prior_recompile = false;
  1373       pdata = query_update_method_data(trap_mdo, trap_bci, reason,
  1374                                    //outputs:
  1375                                    this_trap_count,
  1376                                    maybe_prior_trap,
  1377                                    maybe_prior_recompile);
  1378       // Because the interpreter also counts null, div0, range, and class
  1379       // checks, these traps from compiled code are double-counted.
  1380       // This is harmless; it just means that the PerXTrapLimit values
  1381       // are in effect a little smaller than they look.
  1383       DeoptReason per_bc_reason = reason_recorded_per_bytecode_if_any(reason);
  1384       if (per_bc_reason != Reason_none) {
  1385         // Now take action based on the partially known per-BCI history.
  1386         if (maybe_prior_trap
  1387             && this_trap_count >= (uint)PerBytecodeTrapLimit) {
  1388           // If there are too many traps at this BCI, force a recompile.
  1389           // This will allow the compiler to see the limit overflow, and
  1390           // take corrective action, if possible.  The compiler generally
  1391           // does not use the exact PerBytecodeTrapLimit value, but instead
  1392           // changes its tactics if it sees any traps at all.  This provides
  1393           // a little hysteresis, delaying a recompile until a trap happens
  1394           // several times.
  1395           //
  1396           // Actually, since there is only one bit of counter per BCI,
  1397           // the possible per-BCI counts are {0,1,(per-method count)}.
  1398           // This produces accurate results if in fact there is only
  1399           // one hot trap site, but begins to get fuzzy if there are
  1400           // many sites.  For example, if there are ten sites each
  1401           // trapping two or more times, they each get the blame for
  1402           // all of their traps.
  1403           make_not_entrant = true;
  1406         // Detect repeated recompilation at the same BCI, and enforce a limit.
  1407         if (make_not_entrant && maybe_prior_recompile) {
  1408           // More than one recompile at this point.
  1409           inc_recompile_count = maybe_prior_trap;
  1411       } else {
  1412         // For reasons which are not recorded per-bytecode, we simply
  1413         // force recompiles unconditionally.
  1414         // (Note that PerMethodRecompilationCutoff is enforced elsewhere.)
  1415         make_not_entrant = true;
  1418       // Go back to the compiler if there are too many traps in this method.
  1419       if (this_trap_count >= (uint)PerMethodTrapLimit) {
  1420         // If there are too many traps in this method, force a recompile.
  1421         // This will allow the compiler to see the limit overflow, and
  1422         // take corrective action, if possible.
  1423         // (This condition is an unlikely backstop only, because the
  1424         // PerBytecodeTrapLimit is more likely to take effect first,
  1425         // if it is applicable.)
  1426         make_not_entrant = true;
  1429       // Here's more hysteresis:  If there has been a recompile at
  1430       // this trap point already, run the method in the interpreter
  1431       // for a while to exercise it more thoroughly.
  1432       if (make_not_entrant && maybe_prior_recompile && maybe_prior_trap) {
  1433         reset_counters = true;
  1438     // Take requested actions on the method:
  1440     // Recompile
  1441     if (make_not_entrant) {
  1442       if (!nm->make_not_entrant()) {
  1443         return; // the call did not change nmethod's state
  1446       if (pdata != NULL) {
  1447         // Record the recompilation event, if any.
  1448         int tstate0 = pdata->trap_state();
  1449         int tstate1 = trap_state_set_recompiled(tstate0, true);
  1450         if (tstate1 != tstate0)
  1451           pdata->set_trap_state(tstate1);
  1455     if (inc_recompile_count) {
  1456       trap_mdo->inc_overflow_recompile_count();
  1457       if ((uint)trap_mdo->overflow_recompile_count() >
  1458           (uint)PerBytecodeRecompilationCutoff) {
  1459         // Give up on the method containing the bad BCI.
  1460         if (trap_method() == nm->method()) {
  1461           make_not_compilable = true;
  1462         } else {
  1463           trap_method->set_not_compilable();
  1464           // But give grace to the enclosing nm->method().
  1469     // Reset invocation counters
  1470     if (reset_counters) {
  1471       if (nm->is_osr_method())
  1472         reset_invocation_counter(trap_scope, CompileThreshold);
  1473       else
  1474         reset_invocation_counter(trap_scope);
  1477     // Give up compiling
  1478     if (make_not_compilable && !nm->method()->is_not_compilable()) {
  1479       assert(make_not_entrant, "consistent");
  1480       nm->method()->set_not_compilable();
  1483   } // Free marked resources
  1486 JRT_END
  1488 methodDataOop
  1489 Deoptimization::get_method_data(JavaThread* thread, methodHandle m,
  1490                                 bool create_if_missing) {
  1491   Thread* THREAD = thread;
  1492   methodDataOop mdo = m()->method_data();
  1493   if (mdo == NULL && create_if_missing && !HAS_PENDING_EXCEPTION) {
  1494     // Build an MDO.  Ignore errors like OutOfMemory;
  1495     // that simply means we won't have an MDO to update.
  1496     methodOopDesc::build_interpreter_method_data(m, THREAD);
  1497     if (HAS_PENDING_EXCEPTION) {
  1498       assert((PENDING_EXCEPTION->is_a(SystemDictionary::OutOfMemoryError_klass())), "we expect only an OOM error here");
  1499       CLEAR_PENDING_EXCEPTION;
  1501     mdo = m()->method_data();
  1503   return mdo;
  1506 ProfileData*
  1507 Deoptimization::query_update_method_data(methodDataHandle trap_mdo,
  1508                                          int trap_bci,
  1509                                          Deoptimization::DeoptReason reason,
  1510                                          //outputs:
  1511                                          uint& ret_this_trap_count,
  1512                                          bool& ret_maybe_prior_trap,
  1513                                          bool& ret_maybe_prior_recompile) {
  1514   uint prior_trap_count = trap_mdo->trap_count(reason);
  1515   uint this_trap_count  = trap_mdo->inc_trap_count(reason);
  1517   // If the runtime cannot find a place to store trap history,
  1518   // it is estimated based on the general condition of the method.
  1519   // If the method has ever been recompiled, or has ever incurred
  1520   // a trap with the present reason , then this BCI is assumed
  1521   // (pessimistically) to be the culprit.
  1522   bool maybe_prior_trap      = (prior_trap_count != 0);
  1523   bool maybe_prior_recompile = (trap_mdo->decompile_count() != 0);
  1524   ProfileData* pdata = NULL;
  1527   // For reasons which are recorded per bytecode, we check per-BCI data.
  1528   DeoptReason per_bc_reason = reason_recorded_per_bytecode_if_any(reason);
  1529   if (per_bc_reason != Reason_none) {
  1530     // Find the profile data for this BCI.  If there isn't one,
  1531     // try to allocate one from the MDO's set of spares.
  1532     // This will let us detect a repeated trap at this point.
  1533     pdata = trap_mdo->allocate_bci_to_data(trap_bci);
  1535     if (pdata != NULL) {
  1536       // Query the trap state of this profile datum.
  1537       int tstate0 = pdata->trap_state();
  1538       if (!trap_state_has_reason(tstate0, per_bc_reason))
  1539         maybe_prior_trap = false;
  1540       if (!trap_state_is_recompiled(tstate0))
  1541         maybe_prior_recompile = false;
  1543       // Update the trap state of this profile datum.
  1544       int tstate1 = tstate0;
  1545       // Record the reason.
  1546       tstate1 = trap_state_add_reason(tstate1, per_bc_reason);
  1547       // Store the updated state on the MDO, for next time.
  1548       if (tstate1 != tstate0)
  1549         pdata->set_trap_state(tstate1);
  1550     } else {
  1551       if (LogCompilation && xtty != NULL) {
  1552         ttyLocker ttyl;
  1553         // Missing MDP?  Leave a small complaint in the log.
  1554         xtty->elem("missing_mdp bci='%d'", trap_bci);
  1559   // Return results:
  1560   ret_this_trap_count = this_trap_count;
  1561   ret_maybe_prior_trap = maybe_prior_trap;
  1562   ret_maybe_prior_recompile = maybe_prior_recompile;
  1563   return pdata;
  1566 void
  1567 Deoptimization::update_method_data_from_interpreter(methodDataHandle trap_mdo, int trap_bci, int reason) {
  1568   ResourceMark rm;
  1569   // Ignored outputs:
  1570   uint ignore_this_trap_count;
  1571   bool ignore_maybe_prior_trap;
  1572   bool ignore_maybe_prior_recompile;
  1573   query_update_method_data(trap_mdo, trap_bci,
  1574                            (DeoptReason)reason,
  1575                            ignore_this_trap_count,
  1576                            ignore_maybe_prior_trap,
  1577                            ignore_maybe_prior_recompile);
  1580 void Deoptimization::reset_invocation_counter(ScopeDesc* trap_scope, jint top_count) {
  1581   ScopeDesc* sd = trap_scope;
  1582   for (; !sd->is_top(); sd = sd->sender()) {
  1583     // Reset ICs of inlined methods, since they can trigger compilations also.
  1584     sd->method()->invocation_counter()->reset();
  1586   InvocationCounter* c = sd->method()->invocation_counter();
  1587   if (top_count != _no_count) {
  1588     // It was an OSR method, so bump the count higher.
  1589     c->set(c->state(), top_count);
  1590   } else {
  1591     c->reset();
  1593   sd->method()->backedge_counter()->reset();
  1596 Deoptimization::UnrollBlock* Deoptimization::uncommon_trap(JavaThread* thread, jint trap_request) {
  1598   // Still in Java no safepoints
  1600     // This enters VM and may safepoint
  1601     uncommon_trap_inner(thread, trap_request);
  1603   return fetch_unroll_info_helper(thread);
  1606 // Local derived constants.
  1607 // Further breakdown of DataLayout::trap_state, as promised by DataLayout.
  1608 const int DS_REASON_MASK   = DataLayout::trap_mask >> 1;
  1609 const int DS_RECOMPILE_BIT = DataLayout::trap_mask - DS_REASON_MASK;
  1611 //---------------------------trap_state_reason---------------------------------
  1612 Deoptimization::DeoptReason
  1613 Deoptimization::trap_state_reason(int trap_state) {
  1614   // This assert provides the link between the width of DataLayout::trap_bits
  1615   // and the encoding of "recorded" reasons.  It ensures there are enough
  1616   // bits to store all needed reasons in the per-BCI MDO profile.
  1617   assert(DS_REASON_MASK >= Reason_RECORDED_LIMIT, "enough bits");
  1618   int recompile_bit = (trap_state & DS_RECOMPILE_BIT);
  1619   trap_state -= recompile_bit;
  1620   if (trap_state == DS_REASON_MASK) {
  1621     return Reason_many;
  1622   } else {
  1623     assert((int)Reason_none == 0, "state=0 => Reason_none");
  1624     return (DeoptReason)trap_state;
  1627 //-------------------------trap_state_has_reason-------------------------------
  1628 int Deoptimization::trap_state_has_reason(int trap_state, int reason) {
  1629   assert(reason_is_recorded_per_bytecode((DeoptReason)reason), "valid reason");
  1630   assert(DS_REASON_MASK >= Reason_RECORDED_LIMIT, "enough bits");
  1631   int recompile_bit = (trap_state & DS_RECOMPILE_BIT);
  1632   trap_state -= recompile_bit;
  1633   if (trap_state == DS_REASON_MASK) {
  1634     return -1;  // true, unspecifically (bottom of state lattice)
  1635   } else if (trap_state == reason) {
  1636     return 1;   // true, definitely
  1637   } else if (trap_state == 0) {
  1638     return 0;   // false, definitely (top of state lattice)
  1639   } else {
  1640     return 0;   // false, definitely
  1643 //-------------------------trap_state_add_reason-------------------------------
  1644 int Deoptimization::trap_state_add_reason(int trap_state, int reason) {
  1645   assert(reason_is_recorded_per_bytecode((DeoptReason)reason) || reason == Reason_many, "valid reason");
  1646   int recompile_bit = (trap_state & DS_RECOMPILE_BIT);
  1647   trap_state -= recompile_bit;
  1648   if (trap_state == DS_REASON_MASK) {
  1649     return trap_state + recompile_bit;     // already at state lattice bottom
  1650   } else if (trap_state == reason) {
  1651     return trap_state + recompile_bit;     // the condition is already true
  1652   } else if (trap_state == 0) {
  1653     return reason + recompile_bit;          // no condition has yet been true
  1654   } else {
  1655     return DS_REASON_MASK + recompile_bit;  // fall to state lattice bottom
  1658 //-----------------------trap_state_is_recompiled------------------------------
  1659 bool Deoptimization::trap_state_is_recompiled(int trap_state) {
  1660   return (trap_state & DS_RECOMPILE_BIT) != 0;
  1662 //-----------------------trap_state_set_recompiled-----------------------------
  1663 int Deoptimization::trap_state_set_recompiled(int trap_state, bool z) {
  1664   if (z)  return trap_state |  DS_RECOMPILE_BIT;
  1665   else    return trap_state & ~DS_RECOMPILE_BIT;
  1667 //---------------------------format_trap_state---------------------------------
  1668 // This is used for debugging and diagnostics, including hotspot.log output.
  1669 const char* Deoptimization::format_trap_state(char* buf, size_t buflen,
  1670                                               int trap_state) {
  1671   DeoptReason reason      = trap_state_reason(trap_state);
  1672   bool        recomp_flag = trap_state_is_recompiled(trap_state);
  1673   // Re-encode the state from its decoded components.
  1674   int decoded_state = 0;
  1675   if (reason_is_recorded_per_bytecode(reason) || reason == Reason_many)
  1676     decoded_state = trap_state_add_reason(decoded_state, reason);
  1677   if (recomp_flag)
  1678     decoded_state = trap_state_set_recompiled(decoded_state, recomp_flag);
  1679   // If the state re-encodes properly, format it symbolically.
  1680   // Because this routine is used for debugging and diagnostics,
  1681   // be robust even if the state is a strange value.
  1682   size_t len;
  1683   if (decoded_state != trap_state) {
  1684     // Random buggy state that doesn't decode??
  1685     len = jio_snprintf(buf, buflen, "#%d", trap_state);
  1686   } else {
  1687     len = jio_snprintf(buf, buflen, "%s%s",
  1688                        trap_reason_name(reason),
  1689                        recomp_flag ? " recompiled" : "");
  1691   if (len >= buflen)
  1692     buf[buflen-1] = '\0';
  1693   return buf;
  1697 //--------------------------------statics--------------------------------------
  1698 Deoptimization::DeoptAction Deoptimization::_unloaded_action
  1699   = Deoptimization::Action_reinterpret;
  1700 const char* Deoptimization::_trap_reason_name[Reason_LIMIT] = {
  1701   // Note:  Keep this in sync. with enum DeoptReason.
  1702   "none",
  1703   "null_check",
  1704   "null_assert",
  1705   "range_check",
  1706   "class_check",
  1707   "array_check",
  1708   "intrinsic",
  1709   "bimorphic",
  1710   "unloaded",
  1711   "uninitialized",
  1712   "unreached",
  1713   "unhandled",
  1714   "constraint",
  1715   "div0_check",
  1716   "age",
  1717   "predicate"
  1718 };
  1719 const char* Deoptimization::_trap_action_name[Action_LIMIT] = {
  1720   // Note:  Keep this in sync. with enum DeoptAction.
  1721   "none",
  1722   "maybe_recompile",
  1723   "reinterpret",
  1724   "make_not_entrant",
  1725   "make_not_compilable"
  1726 };
  1728 const char* Deoptimization::trap_reason_name(int reason) {
  1729   if (reason == Reason_many)  return "many";
  1730   if ((uint)reason < Reason_LIMIT)
  1731     return _trap_reason_name[reason];
  1732   static char buf[20];
  1733   sprintf(buf, "reason%d", reason);
  1734   return buf;
  1736 const char* Deoptimization::trap_action_name(int action) {
  1737   if ((uint)action < Action_LIMIT)
  1738     return _trap_action_name[action];
  1739   static char buf[20];
  1740   sprintf(buf, "action%d", action);
  1741   return buf;
  1744 // This is used for debugging and diagnostics, including hotspot.log output.
  1745 const char* Deoptimization::format_trap_request(char* buf, size_t buflen,
  1746                                                 int trap_request) {
  1747   jint unloaded_class_index = trap_request_index(trap_request);
  1748   const char* reason = trap_reason_name(trap_request_reason(trap_request));
  1749   const char* action = trap_action_name(trap_request_action(trap_request));
  1750   size_t len;
  1751   if (unloaded_class_index < 0) {
  1752     len = jio_snprintf(buf, buflen, "reason='%s' action='%s'",
  1753                        reason, action);
  1754   } else {
  1755     len = jio_snprintf(buf, buflen, "reason='%s' action='%s' index='%d'",
  1756                        reason, action, unloaded_class_index);
  1758   if (len >= buflen)
  1759     buf[buflen-1] = '\0';
  1760   return buf;
  1763 juint Deoptimization::_deoptimization_hist
  1764         [Deoptimization::Reason_LIMIT]
  1765     [1 + Deoptimization::Action_LIMIT]
  1766         [Deoptimization::BC_CASE_LIMIT]
  1767   = {0};
  1769 enum {
  1770   LSB_BITS = 8,
  1771   LSB_MASK = right_n_bits(LSB_BITS)
  1772 };
  1774 void Deoptimization::gather_statistics(DeoptReason reason, DeoptAction action,
  1775                                        Bytecodes::Code bc) {
  1776   assert(reason >= 0 && reason < Reason_LIMIT, "oob");
  1777   assert(action >= 0 && action < Action_LIMIT, "oob");
  1778   _deoptimization_hist[Reason_none][0][0] += 1;  // total
  1779   _deoptimization_hist[reason][0][0]      += 1;  // per-reason total
  1780   juint* cases = _deoptimization_hist[reason][1+action];
  1781   juint* bc_counter_addr = NULL;
  1782   juint  bc_counter      = 0;
  1783   // Look for an unused counter, or an exact match to this BC.
  1784   if (bc != Bytecodes::_illegal) {
  1785     for (int bc_case = 0; bc_case < BC_CASE_LIMIT; bc_case++) {
  1786       juint* counter_addr = &cases[bc_case];
  1787       juint  counter = *counter_addr;
  1788       if ((counter == 0 && bc_counter_addr == NULL)
  1789           || (Bytecodes::Code)(counter & LSB_MASK) == bc) {
  1790         // this counter is either free or is already devoted to this BC
  1791         bc_counter_addr = counter_addr;
  1792         bc_counter = counter | bc;
  1796   if (bc_counter_addr == NULL) {
  1797     // Overflow, or no given bytecode.
  1798     bc_counter_addr = &cases[BC_CASE_LIMIT-1];
  1799     bc_counter = (*bc_counter_addr & ~LSB_MASK);  // clear LSB
  1801   *bc_counter_addr = bc_counter + (1 << LSB_BITS);
  1804 jint Deoptimization::total_deoptimization_count() {
  1805   return _deoptimization_hist[Reason_none][0][0];
  1808 jint Deoptimization::deoptimization_count(DeoptReason reason) {
  1809   assert(reason >= 0 && reason < Reason_LIMIT, "oob");
  1810   return _deoptimization_hist[reason][0][0];
  1813 void Deoptimization::print_statistics() {
  1814   juint total = total_deoptimization_count();
  1815   juint account = total;
  1816   if (total != 0) {
  1817     ttyLocker ttyl;
  1818     if (xtty != NULL)  xtty->head("statistics type='deoptimization'");
  1819     tty->print_cr("Deoptimization traps recorded:");
  1820     #define PRINT_STAT_LINE(name, r) \
  1821       tty->print_cr("  %4d (%4.1f%%) %s", (int)(r), ((r) * 100.0) / total, name);
  1822     PRINT_STAT_LINE("total", total);
  1823     // For each non-zero entry in the histogram, print the reason,
  1824     // the action, and (if specifically known) the type of bytecode.
  1825     for (int reason = 0; reason < Reason_LIMIT; reason++) {
  1826       for (int action = 0; action < Action_LIMIT; action++) {
  1827         juint* cases = _deoptimization_hist[reason][1+action];
  1828         for (int bc_case = 0; bc_case < BC_CASE_LIMIT; bc_case++) {
  1829           juint counter = cases[bc_case];
  1830           if (counter != 0) {
  1831             char name[1*K];
  1832             Bytecodes::Code bc = (Bytecodes::Code)(counter & LSB_MASK);
  1833             if (bc_case == BC_CASE_LIMIT && (int)bc == 0)
  1834               bc = Bytecodes::_illegal;
  1835             sprintf(name, "%s/%s/%s",
  1836                     trap_reason_name(reason),
  1837                     trap_action_name(action),
  1838                     Bytecodes::is_defined(bc)? Bytecodes::name(bc): "other");
  1839             juint r = counter >> LSB_BITS;
  1840             tty->print_cr("  %40s: " UINT32_FORMAT " (%.1f%%)", name, r, (r * 100.0) / total);
  1841             account -= r;
  1846     if (account != 0) {
  1847       PRINT_STAT_LINE("unaccounted", account);
  1849     #undef PRINT_STAT_LINE
  1850     if (xtty != NULL)  xtty->tail("statistics");
  1853 #else // COMPILER2
  1856 // Stubs for C1 only system.
  1857 bool Deoptimization::trap_state_is_recompiled(int trap_state) {
  1858   return false;
  1861 const char* Deoptimization::trap_reason_name(int reason) {
  1862   return "unknown";
  1865 void Deoptimization::print_statistics() {
  1866   // no output
  1869 void
  1870 Deoptimization::update_method_data_from_interpreter(methodDataHandle trap_mdo, int trap_bci, int reason) {
  1871   // no udpate
  1874 int Deoptimization::trap_state_has_reason(int trap_state, int reason) {
  1875   return 0;
  1878 void Deoptimization::gather_statistics(DeoptReason reason, DeoptAction action,
  1879                                        Bytecodes::Code bc) {
  1880   // no update
  1883 const char* Deoptimization::format_trap_state(char* buf, size_t buflen,
  1884                                               int trap_state) {
  1885   jio_snprintf(buf, buflen, "#%d", trap_state);
  1886   return buf;
  1889 #endif // COMPILER2

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