1 /*
   2  * Copyright (c) 1997, 2017, Oracle and/or its affiliates. All rights reserved.
   3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   4  *
   5  * This code is free software; you can redistribute it and/or modify it
   6  * under the terms of the GNU General Public License version 2 only, as
   7  * published by the Free Software Foundation.
   8  *
   9  * This code is distributed in the hope that it will be useful, but WITHOUT
  10  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  11  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  12  * version 2 for more details (a copy is included in the LICENSE file that
  13  * accompanied this code).
  14  *
  15  * You should have received a copy of the GNU General Public License version
  16  * 2 along with this work; if not, write to the Free Software Foundation,
  17  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  18  *
  19  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
  20  * or visit www.oracle.com if you need additional information or have any
  21  * questions.
  22  *
  23  */
  24 
  25 #include "precompiled.hpp"
  26 #include "classfile/systemDictionary.hpp"
  27 #include "code/codeCache.hpp"
  28 #include "code/debugInfoRec.hpp"
  29 #include "code/nmethod.hpp"
  30 #include "code/pcDesc.hpp"
  31 #include "code/scopeDesc.hpp"
  32 #include "interpreter/bytecode.hpp"
  33 #include "interpreter/interpreter.hpp"
  34 #include "interpreter/oopMapCache.hpp"
  35 #include "memory/allocation.inline.hpp"
  36 #include "memory/oopFactory.hpp"
  37 #include "memory/resourceArea.hpp"
  38 #include "oops/method.hpp"
  39 #include "oops/objArrayOop.inline.hpp"
  40 #include "oops/oop.inline.hpp"
  41 #include "oops/fieldStreams.hpp"
  42 #include "oops/verifyOopClosure.hpp"
  43 #include "prims/jvm.h"
  44 #include "prims/jvmtiThreadState.hpp"
  45 #include "runtime/biasedLocking.hpp"
  46 #include "runtime/compilationPolicy.hpp"
  47 #include "runtime/deoptimization.hpp"
  48 #include "runtime/interfaceSupport.hpp"
  49 #include "runtime/sharedRuntime.hpp"
  50 #include "runtime/signature.hpp"
  51 #include "runtime/stubRoutines.hpp"
  52 #include "runtime/thread.hpp"
  53 #include "runtime/vframe.hpp"
  54 #include "runtime/vframeArray.hpp"
  55 #include "runtime/vframe_hp.hpp"
  56 #include "utilities/events.hpp"
  57 #include "utilities/xmlstream.hpp"
  58 
  59 #if INCLUDE_JVMCI
  60 #include "jvmci/jvmciRuntime.hpp"
  61 #include "jvmci/jvmciJavaClasses.hpp"
  62 #endif
  63 
  64 
  65 bool DeoptimizationMarker::_is_active = false;
  66 
  67 Deoptimization::UnrollBlock::UnrollBlock(int  size_of_deoptimized_frame,
  68                                          int  caller_adjustment,
  69                                          int  caller_actual_parameters,
  70                                          int  number_of_frames,
  71                                          intptr_t* frame_sizes,
  72                                          address* frame_pcs,
  73                                          BasicType return_type,
  74                                          int exec_mode) {
  75   _size_of_deoptimized_frame = size_of_deoptimized_frame;
  76   _caller_adjustment         = caller_adjustment;
  77   _caller_actual_parameters  = caller_actual_parameters;
  78   _number_of_frames          = number_of_frames;
  79   _frame_sizes               = frame_sizes;
  80   _frame_pcs                 = frame_pcs;
  81   _register_block            = NEW_C_HEAP_ARRAY(intptr_t, RegisterMap::reg_count * 2, mtCompiler);
  82   _return_type               = return_type;
  83   _initial_info              = 0;
  84   // PD (x86 only)
  85   _counter_temp              = 0;
  86   _unpack_kind               = exec_mode;
  87   _sender_sp_temp            = 0;
  88 
  89   _total_frame_sizes         = size_of_frames();
  90   assert(exec_mode >= 0 && exec_mode < Unpack_LIMIT, "Unexpected exec_mode");
  91 }
  92 
  93 
  94 Deoptimization::UnrollBlock::~UnrollBlock() {
  95   FREE_C_HEAP_ARRAY(intptr_t, _frame_sizes);
  96   FREE_C_HEAP_ARRAY(intptr_t, _frame_pcs);
  97   FREE_C_HEAP_ARRAY(intptr_t, _register_block);
  98 }
  99 
 100 
 101 intptr_t* Deoptimization::UnrollBlock::value_addr_at(int register_number) const {
 102   assert(register_number < RegisterMap::reg_count, "checking register number");
 103   return &_register_block[register_number * 2];
 104 }
 105 
 106 
 107 
 108 int Deoptimization::UnrollBlock::size_of_frames() const {
 109   // Acount first for the adjustment of the initial frame
 110   int result = _caller_adjustment;
 111   for (int index = 0; index < number_of_frames(); index++) {
 112     result += frame_sizes()[index];
 113   }
 114   return result;
 115 }
 116 
 117 
 118 void Deoptimization::UnrollBlock::print() {
 119   ttyLocker ttyl;
 120   tty->print_cr("UnrollBlock");
 121   tty->print_cr("  size_of_deoptimized_frame = %d", _size_of_deoptimized_frame);
 122   tty->print(   "  frame_sizes: ");
 123   for (int index = 0; index < number_of_frames(); index++) {
 124     tty->print(INTX_FORMAT " ", frame_sizes()[index]);
 125   }
 126   tty->cr();
 127 }
 128 
 129 
 130 // In order to make fetch_unroll_info work properly with escape
 131 // analysis, The method was changed from JRT_LEAF to JRT_BLOCK_ENTRY and
 132 // ResetNoHandleMark and HandleMark were removed from it. The actual reallocation
 133 // of previously eliminated objects occurs in realloc_objects, which is
 134 // called from the method fetch_unroll_info_helper below.
 135 JRT_BLOCK_ENTRY(Deoptimization::UnrollBlock*, Deoptimization::fetch_unroll_info(JavaThread* thread, int exec_mode))
 136   // It is actually ok to allocate handles in a leaf method. It causes no safepoints,
 137   // but makes the entry a little slower. There is however a little dance we have to
 138   // do in debug mode to get around the NoHandleMark code in the JRT_LEAF macro
 139 
 140   // fetch_unroll_info() is called at the beginning of the deoptimization
 141   // handler. Note this fact before we start generating temporary frames
 142   // that can confuse an asynchronous stack walker. This counter is
 143   // decremented at the end of unpack_frames().
 144   if (TraceDeoptimization) {
 145     tty->print_cr("Deoptimizing thread " INTPTR_FORMAT, p2i(thread));
 146   }
 147   thread->inc_in_deopt_handler();
 148 
 149   return fetch_unroll_info_helper(thread, exec_mode);
 150 JRT_END
 151 
 152 
 153 // This is factored, since it is both called from a JRT_LEAF (deoptimization) and a JRT_ENTRY (uncommon_trap)
 154 Deoptimization::UnrollBlock* Deoptimization::fetch_unroll_info_helper(JavaThread* thread, int exec_mode) {
 155 
 156   // Note: there is a safepoint safety issue here. No matter whether we enter
 157   // via vanilla deopt or uncommon trap we MUST NOT stop at a safepoint once
 158   // the vframeArray is created.
 159   //
 160 
 161   // Allocate our special deoptimization ResourceMark
 162   DeoptResourceMark* dmark = new DeoptResourceMark(thread);
 163   assert(thread->deopt_mark() == NULL, "Pending deopt!");
 164   thread->set_deopt_mark(dmark);
 165 
 166   frame stub_frame = thread->last_frame(); // Makes stack walkable as side effect
 167   RegisterMap map(thread, true);
 168   RegisterMap dummy_map(thread, false);
 169   // Now get the deoptee with a valid map
 170   frame deoptee = stub_frame.sender(&map);
 171   // Set the deoptee nmethod
 172   assert(thread->deopt_compiled_method() == NULL, "Pending deopt!");
 173   CompiledMethod* cm = deoptee.cb()->as_compiled_method_or_null();
 174   thread->set_deopt_compiled_method(cm);
 175 
 176   if (VerifyStack) {
 177     thread->validate_frame_layout();
 178   }
 179 
 180   // Create a growable array of VFrames where each VFrame represents an inlined
 181   // Java frame.  This storage is allocated with the usual system arena.
 182   assert(deoptee.is_compiled_frame(), "Wrong frame type");
 183   GrowableArray<compiledVFrame*>* chunk = new GrowableArray<compiledVFrame*>(10);
 184   vframe* vf = vframe::new_vframe(&deoptee, &map, thread);
 185   while (!vf->is_top()) {
 186     assert(vf->is_compiled_frame(), "Wrong frame type");
 187     chunk->push(compiledVFrame::cast(vf));
 188     vf = vf->sender();
 189   }
 190   assert(vf->is_compiled_frame(), "Wrong frame type");
 191   chunk->push(compiledVFrame::cast(vf));
 192 
 193   bool realloc_failures = false;
 194 
 195 #if defined(COMPILER2) || INCLUDE_JVMCI
 196   // Reallocate the non-escaping objects and restore their fields. Then
 197   // relock objects if synchronization on them was eliminated.
 198 #ifndef INCLUDE_JVMCI
 199   if (DoEscapeAnalysis || EliminateNestedLocks) {
 200     if (EliminateAllocations) {
 201 #endif // INCLUDE_JVMCI
 202       assert (chunk->at(0)->scope() != NULL,"expect only compiled java frames");
 203       GrowableArray<ScopeValue*>* objects = chunk->at(0)->scope()->objects();
 204 
 205       // The flag return_oop() indicates call sites which return oop
 206       // in compiled code. Such sites include java method calls,
 207       // runtime calls (for example, used to allocate new objects/arrays
 208       // on slow code path) and any other calls generated in compiled code.
 209       // It is not guaranteed that we can get such information here only
 210       // by analyzing bytecode in deoptimized frames. This is why this flag
 211       // is set during method compilation (see Compile::Process_OopMap_Node()).
 212       // If the previous frame was popped or if we are dispatching an exception,
 213       // we don't have an oop result.
 214       bool save_oop_result = chunk->at(0)->scope()->return_oop() && !thread->popframe_forcing_deopt_reexecution() && (exec_mode == Unpack_deopt);
 215       Handle return_value;
 216       if (save_oop_result) {
 217         // Reallocation may trigger GC. If deoptimization happened on return from
 218         // call which returns oop we need to save it since it is not in oopmap.
 219         oop result = deoptee.saved_oop_result(&map);
 220         assert(result == NULL || oopDesc::is_oop(result), "must be oop");
 221         return_value = Handle(thread, result);
 222         assert(Universe::heap()->is_in_or_null(result), "must be heap pointer");
 223         if (TraceDeoptimization) {
 224           ttyLocker ttyl;
 225           tty->print_cr("SAVED OOP RESULT " INTPTR_FORMAT " in thread " INTPTR_FORMAT, p2i(result), p2i(thread));
 226         }
 227       }
 228       if (objects != NULL) {
 229         JRT_BLOCK
 230           realloc_failures = realloc_objects(thread, &deoptee, objects, THREAD);
 231         JRT_END
 232         bool skip_internal = (cm != NULL) && !cm->is_compiled_by_jvmci();
 233         reassign_fields(&deoptee, &map, objects, realloc_failures, skip_internal);
 234 #ifndef PRODUCT
 235         if (TraceDeoptimization) {
 236           ttyLocker ttyl;
 237           tty->print_cr("REALLOC OBJECTS in thread " INTPTR_FORMAT, p2i(thread));
 238           print_objects(objects, realloc_failures);
 239         }
 240 #endif
 241       }
 242       if (save_oop_result) {
 243         // Restore result.
 244         deoptee.set_saved_oop_result(&map, return_value());
 245       }
 246 #ifndef INCLUDE_JVMCI
 247     }
 248     if (EliminateLocks) {
 249 #endif // INCLUDE_JVMCI
 250 #ifndef PRODUCT
 251       bool first = true;
 252 #endif
 253       for (int i = 0; i < chunk->length(); i++) {
 254         compiledVFrame* cvf = chunk->at(i);
 255         assert (cvf->scope() != NULL,"expect only compiled java frames");
 256         GrowableArray<MonitorInfo*>* monitors = cvf->monitors();
 257         if (monitors->is_nonempty()) {
 258           relock_objects(monitors, thread, realloc_failures);
 259 #ifndef PRODUCT
 260           if (PrintDeoptimizationDetails) {
 261             ttyLocker ttyl;
 262             for (int j = 0; j < monitors->length(); j++) {
 263               MonitorInfo* mi = monitors->at(j);
 264               if (mi->eliminated()) {
 265                 if (first) {
 266                   first = false;
 267                   tty->print_cr("RELOCK OBJECTS in thread " INTPTR_FORMAT, p2i(thread));
 268                 }
 269                 if (mi->owner_is_scalar_replaced()) {
 270                   Klass* k = java_lang_Class::as_Klass(mi->owner_klass());
 271                   tty->print_cr("     failed reallocation for klass %s", k->external_name());
 272                 } else {
 273                   tty->print_cr("     object <" INTPTR_FORMAT "> locked", p2i(mi->owner()));
 274                 }
 275               }
 276             }
 277           }
 278 #endif // !PRODUCT
 279         }
 280       }
 281 #ifndef INCLUDE_JVMCI
 282     }
 283   }
 284 #endif // INCLUDE_JVMCI
 285 #endif // COMPILER2 || INCLUDE_JVMCI
 286 
 287   ScopeDesc* trap_scope = chunk->at(0)->scope();
 288   Handle exceptionObject;
 289   if (trap_scope->rethrow_exception()) {
 290     if (PrintDeoptimizationDetails) {
 291       tty->print_cr("Exception to be rethrown in the interpreter for method %s::%s at bci %d", trap_scope->method()->method_holder()->name()->as_C_string(), trap_scope->method()->name()->as_C_string(), trap_scope->bci());
 292     }
 293     GrowableArray<ScopeValue*>* expressions = trap_scope->expressions();
 294     guarantee(expressions != NULL && expressions->length() > 0, "must have exception to throw");
 295     ScopeValue* topOfStack = expressions->top();
 296     exceptionObject = StackValue::create_stack_value(&deoptee, &map, topOfStack)->get_obj();
 297     guarantee(exceptionObject() != NULL, "exception oop can not be null");
 298   }
 299 
 300   // Ensure that no safepoint is taken after pointers have been stored
 301   // in fields of rematerialized objects.  If a safepoint occurs from here on
 302   // out the java state residing in the vframeArray will be missed.
 303   NoSafepointVerifier no_safepoint;
 304 
 305   vframeArray* array = create_vframeArray(thread, deoptee, &map, chunk, realloc_failures);
 306 #if defined(COMPILER2) || INCLUDE_JVMCI
 307   if (realloc_failures) {
 308     pop_frames_failed_reallocs(thread, array);
 309   }
 310 #endif
 311 
 312   assert(thread->vframe_array_head() == NULL, "Pending deopt!");
 313   thread->set_vframe_array_head(array);
 314 
 315   // Now that the vframeArray has been created if we have any deferred local writes
 316   // added by jvmti then we can free up that structure as the data is now in the
 317   // vframeArray
 318 
 319   if (thread->deferred_locals() != NULL) {
 320     GrowableArray<jvmtiDeferredLocalVariableSet*>* list = thread->deferred_locals();
 321     int i = 0;
 322     do {
 323       // Because of inlining we could have multiple vframes for a single frame
 324       // and several of the vframes could have deferred writes. Find them all.
 325       if (list->at(i)->id() == array->original().id()) {
 326         jvmtiDeferredLocalVariableSet* dlv = list->at(i);
 327         list->remove_at(i);
 328         // individual jvmtiDeferredLocalVariableSet are CHeapObj's
 329         delete dlv;
 330       } else {
 331         i++;
 332       }
 333     } while ( i < list->length() );
 334     if (list->length() == 0) {
 335       thread->set_deferred_locals(NULL);
 336       // free the list and elements back to C heap.
 337       delete list;
 338     }
 339 
 340   }
 341 
 342 #ifndef SHARK
 343   // Compute the caller frame based on the sender sp of stub_frame and stored frame sizes info.
 344   CodeBlob* cb = stub_frame.cb();
 345   // Verify we have the right vframeArray
 346   assert(cb->frame_size() >= 0, "Unexpected frame size");
 347   intptr_t* unpack_sp = stub_frame.sp() + cb->frame_size();
 348 
 349   // If the deopt call site is a MethodHandle invoke call site we have
 350   // to adjust the unpack_sp.
 351   nmethod* deoptee_nm = deoptee.cb()->as_nmethod_or_null();
 352   if (deoptee_nm != NULL && deoptee_nm->is_method_handle_return(deoptee.pc()))
 353     unpack_sp = deoptee.unextended_sp();
 354 
 355 #ifdef ASSERT
 356   assert(cb->is_deoptimization_stub() ||
 357          cb->is_uncommon_trap_stub() ||
 358          strcmp("Stub<DeoptimizationStub.deoptimizationHandler>", cb->name()) == 0 ||
 359          strcmp("Stub<UncommonTrapStub.uncommonTrapHandler>", cb->name()) == 0,
 360          "unexpected code blob: %s", cb->name());
 361 #endif
 362 #else
 363   intptr_t* unpack_sp = stub_frame.sender(&dummy_map).unextended_sp();
 364 #endif // !SHARK
 365 
 366   // This is a guarantee instead of an assert because if vframe doesn't match
 367   // we will unpack the wrong deoptimized frame and wind up in strange places
 368   // where it will be very difficult to figure out what went wrong. Better
 369   // to die an early death here than some very obscure death later when the
 370   // trail is cold.
 371   // Note: on ia64 this guarantee can be fooled by frames with no memory stack
 372   // in that it will fail to detect a problem when there is one. This needs
 373   // more work in tiger timeframe.
 374   guarantee(array->unextended_sp() == unpack_sp, "vframe_array_head must contain the vframeArray to unpack");
 375 
 376   int number_of_frames = array->frames();
 377 
 378   // Compute the vframes' sizes.  Note that frame_sizes[] entries are ordered from outermost to innermost
 379   // virtual activation, which is the reverse of the elements in the vframes array.
 380   intptr_t* frame_sizes = NEW_C_HEAP_ARRAY(intptr_t, number_of_frames, mtCompiler);
 381   // +1 because we always have an interpreter return address for the final slot.
 382   address* frame_pcs = NEW_C_HEAP_ARRAY(address, number_of_frames + 1, mtCompiler);
 383   int popframe_extra_args = 0;
 384   // Create an interpreter return address for the stub to use as its return
 385   // address so the skeletal frames are perfectly walkable
 386   frame_pcs[number_of_frames] = Interpreter::deopt_entry(vtos, 0);
 387 
 388   // PopFrame requires that the preserved incoming arguments from the recently-popped topmost
 389   // activation be put back on the expression stack of the caller for reexecution
 390   if (JvmtiExport::can_pop_frame() && thread->popframe_forcing_deopt_reexecution()) {
 391     popframe_extra_args = in_words(thread->popframe_preserved_args_size_in_words());
 392   }
 393 
 394   // Find the current pc for sender of the deoptee. Since the sender may have been deoptimized
 395   // itself since the deoptee vframeArray was created we must get a fresh value of the pc rather
 396   // than simply use array->sender.pc(). This requires us to walk the current set of frames
 397   //
 398   frame deopt_sender = stub_frame.sender(&dummy_map); // First is the deoptee frame
 399   deopt_sender = deopt_sender.sender(&dummy_map);     // Now deoptee caller
 400 
 401   // It's possible that the number of parameters at the call site is
 402   // different than number of arguments in the callee when method
 403   // handles are used.  If the caller is interpreted get the real
 404   // value so that the proper amount of space can be added to it's
 405   // frame.
 406   bool caller_was_method_handle = false;
 407   if (deopt_sender.is_interpreted_frame()) {
 408     methodHandle method = deopt_sender.interpreter_frame_method();
 409     Bytecode_invoke cur = Bytecode_invoke_check(method, deopt_sender.interpreter_frame_bci());
 410     if (cur.is_invokedynamic() || cur.is_invokehandle()) {
 411       // Method handle invokes may involve fairly arbitrary chains of
 412       // calls so it's impossible to know how much actual space the
 413       // caller has for locals.
 414       caller_was_method_handle = true;
 415     }
 416   }
 417 
 418   //
 419   // frame_sizes/frame_pcs[0] oldest frame (int or c2i)
 420   // frame_sizes/frame_pcs[1] next oldest frame (int)
 421   // frame_sizes/frame_pcs[n] youngest frame (int)
 422   //
 423   // Now a pc in frame_pcs is actually the return address to the frame's caller (a frame
 424   // owns the space for the return address to it's caller).  Confusing ain't it.
 425   //
 426   // The vframe array can address vframes with indices running from
 427   // 0.._frames-1. Index  0 is the youngest frame and _frame - 1 is the oldest (root) frame.
 428   // When we create the skeletal frames we need the oldest frame to be in the zero slot
 429   // in the frame_sizes/frame_pcs so the assembly code can do a trivial walk.
 430   // so things look a little strange in this loop.
 431   //
 432   int callee_parameters = 0;
 433   int callee_locals = 0;
 434   for (int index = 0; index < array->frames(); index++ ) {
 435     // frame[number_of_frames - 1 ] = on_stack_size(youngest)
 436     // frame[number_of_frames - 2 ] = on_stack_size(sender(youngest))
 437     // frame[number_of_frames - 3 ] = on_stack_size(sender(sender(youngest)))
 438     frame_sizes[number_of_frames - 1 - index] = BytesPerWord * array->element(index)->on_stack_size(callee_parameters,
 439                                                                                                     callee_locals,
 440                                                                                                     index == 0,
 441                                                                                                     popframe_extra_args);
 442     // This pc doesn't have to be perfect just good enough to identify the frame
 443     // as interpreted so the skeleton frame will be walkable
 444     // The correct pc will be set when the skeleton frame is completely filled out
 445     // The final pc we store in the loop is wrong and will be overwritten below
 446     frame_pcs[number_of_frames - 1 - index ] = Interpreter::deopt_entry(vtos, 0) - frame::pc_return_offset;
 447 
 448     callee_parameters = array->element(index)->method()->size_of_parameters();
 449     callee_locals = array->element(index)->method()->max_locals();
 450     popframe_extra_args = 0;
 451   }
 452 
 453   // Compute whether the root vframe returns a float or double value.
 454   BasicType return_type;
 455   {
 456     methodHandle method(thread, array->element(0)->method());
 457     Bytecode_invoke invoke = Bytecode_invoke_check(method, array->element(0)->bci());
 458     return_type = invoke.is_valid() ? invoke.result_type() : T_ILLEGAL;
 459   }
 460 
 461   // Compute information for handling adapters and adjusting the frame size of the caller.
 462   int caller_adjustment = 0;
 463 
 464   // Compute the amount the oldest interpreter frame will have to adjust
 465   // its caller's stack by. If the caller is a compiled frame then
 466   // we pretend that the callee has no parameters so that the
 467   // extension counts for the full amount of locals and not just
 468   // locals-parms. This is because without a c2i adapter the parm
 469   // area as created by the compiled frame will not be usable by
 470   // the interpreter. (Depending on the calling convention there
 471   // may not even be enough space).
 472 
 473   // QQQ I'd rather see this pushed down into last_frame_adjust
 474   // and have it take the sender (aka caller).
 475 
 476   if (deopt_sender.is_compiled_frame() || caller_was_method_handle) {
 477     caller_adjustment = last_frame_adjust(0, callee_locals);
 478   } else if (callee_locals > callee_parameters) {
 479     // The caller frame may need extending to accommodate
 480     // non-parameter locals of the first unpacked interpreted frame.
 481     // Compute that adjustment.
 482     caller_adjustment = last_frame_adjust(callee_parameters, callee_locals);
 483   }
 484 
 485   // If the sender is deoptimized the we must retrieve the address of the handler
 486   // since the frame will "magically" show the original pc before the deopt
 487   // and we'd undo the deopt.
 488 
 489   frame_pcs[0] = deopt_sender.raw_pc();
 490 
 491 #ifndef SHARK
 492   assert(CodeCache::find_blob_unsafe(frame_pcs[0]) != NULL, "bad pc");
 493 #endif // SHARK
 494 
 495 #ifdef INCLUDE_JVMCI
 496   if (exceptionObject() != NULL) {
 497     thread->set_exception_oop(exceptionObject());
 498     exec_mode = Unpack_exception;
 499   }
 500 #endif
 501 
 502   if (thread->frames_to_pop_failed_realloc() > 0 && exec_mode != Unpack_uncommon_trap) {
 503     assert(thread->has_pending_exception(), "should have thrown OOME");
 504     thread->set_exception_oop(thread->pending_exception());
 505     thread->clear_pending_exception();
 506     exec_mode = Unpack_exception;
 507   }
 508 
 509 #if INCLUDE_JVMCI
 510   if (thread->frames_to_pop_failed_realloc() > 0) {
 511     thread->set_pending_monitorenter(false);
 512   }
 513 #endif
 514 
 515   UnrollBlock* info = new UnrollBlock(array->frame_size() * BytesPerWord,
 516                                       caller_adjustment * BytesPerWord,
 517                                       caller_was_method_handle ? 0 : callee_parameters,
 518                                       number_of_frames,
 519                                       frame_sizes,
 520                                       frame_pcs,
 521                                       return_type,
 522                                       exec_mode);
 523   // On some platforms, we need a way to pass some platform dependent
 524   // information to the unpacking code so the skeletal frames come out
 525   // correct (initial fp value, unextended sp, ...)
 526   info->set_initial_info((intptr_t) array->sender().initial_deoptimization_info());
 527 
 528   if (array->frames() > 1) {
 529     if (VerifyStack && TraceDeoptimization) {
 530       ttyLocker ttyl;
 531       tty->print_cr("Deoptimizing method containing inlining");
 532     }
 533   }
 534 
 535   array->set_unroll_block(info);
 536   return info;
 537 }
 538 
 539 // Called to cleanup deoptimization data structures in normal case
 540 // after unpacking to stack and when stack overflow error occurs
 541 void Deoptimization::cleanup_deopt_info(JavaThread *thread,
 542                                         vframeArray *array) {
 543 
 544   // Get array if coming from exception
 545   if (array == NULL) {
 546     array = thread->vframe_array_head();
 547   }
 548   thread->set_vframe_array_head(NULL);
 549 
 550   // Free the previous UnrollBlock
 551   vframeArray* old_array = thread->vframe_array_last();
 552   thread->set_vframe_array_last(array);
 553 
 554   if (old_array != NULL) {
 555     UnrollBlock* old_info = old_array->unroll_block();
 556     old_array->set_unroll_block(NULL);
 557     delete old_info;
 558     delete old_array;
 559   }
 560 
 561   // Deallocate any resource creating in this routine and any ResourceObjs allocated
 562   // inside the vframeArray (StackValueCollections)
 563 
 564   delete thread->deopt_mark();
 565   thread->set_deopt_mark(NULL);
 566   thread->set_deopt_compiled_method(NULL);
 567 
 568 
 569   if (JvmtiExport::can_pop_frame()) {
 570 #ifndef CC_INTERP
 571     // Regardless of whether we entered this routine with the pending
 572     // popframe condition bit set, we should always clear it now
 573     thread->clear_popframe_condition();
 574 #else
 575     // C++ interpreter will clear has_pending_popframe when it enters
 576     // with method_resume. For deopt_resume2 we clear it now.
 577     if (thread->popframe_forcing_deopt_reexecution())
 578         thread->clear_popframe_condition();
 579 #endif /* CC_INTERP */
 580   }
 581 
 582   // unpack_frames() is called at the end of the deoptimization handler
 583   // and (in C2) at the end of the uncommon trap handler. Note this fact
 584   // so that an asynchronous stack walker can work again. This counter is
 585   // incremented at the beginning of fetch_unroll_info() and (in C2) at
 586   // the beginning of uncommon_trap().
 587   thread->dec_in_deopt_handler();
 588 }
 589 
 590 // Moved from cpu directories because none of the cpus has callee save values.
 591 // If a cpu implements callee save values, move this to deoptimization_<cpu>.cpp.
 592 void Deoptimization::unwind_callee_save_values(frame* f, vframeArray* vframe_array) {
 593 
 594   // This code is sort of the equivalent of C2IAdapter::setup_stack_frame back in
 595   // the days we had adapter frames. When we deoptimize a situation where a
 596   // compiled caller calls a compiled caller will have registers it expects
 597   // to survive the call to the callee. If we deoptimize the callee the only
 598   // way we can restore these registers is to have the oldest interpreter
 599   // frame that we create restore these values. That is what this routine
 600   // will accomplish.
 601 
 602   // At the moment we have modified c2 to not have any callee save registers
 603   // so this problem does not exist and this routine is just a place holder.
 604 
 605   assert(f->is_interpreted_frame(), "must be interpreted");
 606 }
 607 
 608 // Return BasicType of value being returned
 609 JRT_LEAF(BasicType, Deoptimization::unpack_frames(JavaThread* thread, int exec_mode))
 610 
 611   // We are already active int he special DeoptResourceMark any ResourceObj's we
 612   // allocate will be freed at the end of the routine.
 613 
 614   // It is actually ok to allocate handles in a leaf method. It causes no safepoints,
 615   // but makes the entry a little slower. There is however a little dance we have to
 616   // do in debug mode to get around the NoHandleMark code in the JRT_LEAF macro
 617   ResetNoHandleMark rnhm; // No-op in release/product versions
 618   HandleMark hm;
 619 
 620   frame stub_frame = thread->last_frame();
 621 
 622   // Since the frame to unpack is the top frame of this thread, the vframe_array_head
 623   // must point to the vframeArray for the unpack frame.
 624   vframeArray* array = thread->vframe_array_head();
 625 
 626 #ifndef PRODUCT
 627   if (TraceDeoptimization) {
 628     ttyLocker ttyl;
 629     tty->print_cr("DEOPT UNPACKING thread " INTPTR_FORMAT " vframeArray " INTPTR_FORMAT " mode %d",
 630                   p2i(thread), p2i(array), exec_mode);
 631   }
 632 #endif
 633   Events::log(thread, "DEOPT UNPACKING pc=" INTPTR_FORMAT " sp=" INTPTR_FORMAT " mode %d",
 634               p2i(stub_frame.pc()), p2i(stub_frame.sp()), exec_mode);
 635 
 636   UnrollBlock* info = array->unroll_block();
 637 
 638   // Unpack the interpreter frames and any adapter frame (c2 only) we might create.
 639   array->unpack_to_stack(stub_frame, exec_mode, info->caller_actual_parameters());
 640 
 641   BasicType bt = info->return_type();
 642 
 643   // If we have an exception pending, claim that the return type is an oop
 644   // so the deopt_blob does not overwrite the exception_oop.
 645 
 646   if (exec_mode == Unpack_exception)
 647     bt = T_OBJECT;
 648 
 649   // Cleanup thread deopt data
 650   cleanup_deopt_info(thread, array);
 651 
 652 #ifndef PRODUCT
 653   if (VerifyStack) {
 654     ResourceMark res_mark;
 655 
 656     thread->validate_frame_layout();
 657 
 658     // Verify that the just-unpacked frames match the interpreter's
 659     // notions of expression stack and locals
 660     vframeArray* cur_array = thread->vframe_array_last();
 661     RegisterMap rm(thread, false);
 662     rm.set_include_argument_oops(false);
 663     bool is_top_frame = true;
 664     int callee_size_of_parameters = 0;
 665     int callee_max_locals = 0;
 666     for (int i = 0; i < cur_array->frames(); i++) {
 667       vframeArrayElement* el = cur_array->element(i);
 668       frame* iframe = el->iframe();
 669       guarantee(iframe->is_interpreted_frame(), "Wrong frame type");
 670 
 671       // Get the oop map for this bci
 672       InterpreterOopMap mask;
 673       int cur_invoke_parameter_size = 0;
 674       bool try_next_mask = false;
 675       int next_mask_expression_stack_size = -1;
 676       int top_frame_expression_stack_adjustment = 0;
 677       methodHandle mh(thread, iframe->interpreter_frame_method());
 678       OopMapCache::compute_one_oop_map(mh, iframe->interpreter_frame_bci(), &mask);
 679       BytecodeStream str(mh);
 680       str.set_start(iframe->interpreter_frame_bci());
 681       int max_bci = mh->code_size();
 682       // Get to the next bytecode if possible
 683       assert(str.bci() < max_bci, "bci in interpreter frame out of bounds");
 684       // Check to see if we can grab the number of outgoing arguments
 685       // at an uncommon trap for an invoke (where the compiler
 686       // generates debug info before the invoke has executed)
 687       Bytecodes::Code cur_code = str.next();
 688       if (cur_code == Bytecodes::_invokevirtual   ||
 689           cur_code == Bytecodes::_invokespecial   ||
 690           cur_code == Bytecodes::_invokestatic    ||
 691           cur_code == Bytecodes::_invokeinterface ||
 692           cur_code == Bytecodes::_invokedynamic) {
 693         Bytecode_invoke invoke(mh, iframe->interpreter_frame_bci());
 694         Symbol* signature = invoke.signature();
 695         ArgumentSizeComputer asc(signature);
 696         cur_invoke_parameter_size = asc.size();
 697         if (invoke.has_receiver()) {
 698           // Add in receiver
 699           ++cur_invoke_parameter_size;
 700         }
 701         if (i != 0 && !invoke.is_invokedynamic() && MethodHandles::has_member_arg(invoke.klass(), invoke.name())) {
 702           callee_size_of_parameters++;
 703         }
 704       }
 705       if (str.bci() < max_bci) {
 706         Bytecodes::Code bc = str.next();
 707         if (bc >= 0) {
 708           // The interpreter oop map generator reports results before
 709           // the current bytecode has executed except in the case of
 710           // calls. It seems to be hard to tell whether the compiler
 711           // has emitted debug information matching the "state before"
 712           // a given bytecode or the state after, so we try both
 713           switch (cur_code) {
 714             case Bytecodes::_invokevirtual:
 715             case Bytecodes::_invokespecial:
 716             case Bytecodes::_invokestatic:
 717             case Bytecodes::_invokeinterface:
 718             case Bytecodes::_invokedynamic:
 719             case Bytecodes::_athrow:
 720               break;
 721             default: {
 722               InterpreterOopMap next_mask;
 723               OopMapCache::compute_one_oop_map(mh, str.bci(), &next_mask);
 724               next_mask_expression_stack_size = next_mask.expression_stack_size();
 725               // Need to subtract off the size of the result type of
 726               // the bytecode because this is not described in the
 727               // debug info but returned to the interpreter in the TOS
 728               // caching register
 729               BasicType bytecode_result_type = Bytecodes::result_type(cur_code);
 730               if (bytecode_result_type != T_ILLEGAL) {
 731                 top_frame_expression_stack_adjustment = type2size[bytecode_result_type];
 732               }
 733               assert(top_frame_expression_stack_adjustment >= 0, "");
 734               try_next_mask = true;
 735               break;
 736             }
 737           }
 738         }
 739       }
 740 
 741       // Verify stack depth and oops in frame
 742       // This assertion may be dependent on the platform we're running on and may need modification (tested on x86 and sparc)
 743       if (!(
 744             /* SPARC */
 745             (iframe->interpreter_frame_expression_stack_size() == mask.expression_stack_size() + callee_size_of_parameters) ||
 746             /* x86 */
 747             (iframe->interpreter_frame_expression_stack_size() == mask.expression_stack_size() + callee_max_locals) ||
 748             (try_next_mask &&
 749              (iframe->interpreter_frame_expression_stack_size() == (next_mask_expression_stack_size -
 750                                                                     top_frame_expression_stack_adjustment))) ||
 751             (is_top_frame && (exec_mode == Unpack_exception) && iframe->interpreter_frame_expression_stack_size() == 0) ||
 752             (is_top_frame && (exec_mode == Unpack_uncommon_trap || exec_mode == Unpack_reexecute || el->should_reexecute()) &&
 753              (iframe->interpreter_frame_expression_stack_size() == mask.expression_stack_size() + cur_invoke_parameter_size))
 754             )) {
 755         ttyLocker ttyl;
 756 
 757         // Print out some information that will help us debug the problem
 758         tty->print_cr("Wrong number of expression stack elements during deoptimization");
 759         tty->print_cr("  Error occurred while verifying frame %d (0..%d, 0 is topmost)", i, cur_array->frames() - 1);
 760         tty->print_cr("  Fabricated interpreter frame had %d expression stack elements",
 761                       iframe->interpreter_frame_expression_stack_size());
 762         tty->print_cr("  Interpreter oop map had %d expression stack elements", mask.expression_stack_size());
 763         tty->print_cr("  try_next_mask = %d", try_next_mask);
 764         tty->print_cr("  next_mask_expression_stack_size = %d", next_mask_expression_stack_size);
 765         tty->print_cr("  callee_size_of_parameters = %d", callee_size_of_parameters);
 766         tty->print_cr("  callee_max_locals = %d", callee_max_locals);
 767         tty->print_cr("  top_frame_expression_stack_adjustment = %d", top_frame_expression_stack_adjustment);
 768         tty->print_cr("  exec_mode = %d", exec_mode);
 769         tty->print_cr("  cur_invoke_parameter_size = %d", cur_invoke_parameter_size);
 770         tty->print_cr("  Thread = " INTPTR_FORMAT ", thread ID = %d", p2i(thread), thread->osthread()->thread_id());
 771         tty->print_cr("  Interpreted frames:");
 772         for (int k = 0; k < cur_array->frames(); k++) {
 773           vframeArrayElement* el = cur_array->element(k);
 774           tty->print_cr("    %s (bci %d)", el->method()->name_and_sig_as_C_string(), el->bci());
 775         }
 776         cur_array->print_on_2(tty);
 777         guarantee(false, "wrong number of expression stack elements during deopt");
 778       }
 779       VerifyOopClosure verify;
 780       iframe->oops_interpreted_do(&verify, &rm, false);
 781       callee_size_of_parameters = mh->size_of_parameters();
 782       callee_max_locals = mh->max_locals();
 783       is_top_frame = false;
 784     }
 785   }
 786 #endif /* !PRODUCT */
 787 
 788 
 789   return bt;
 790 JRT_END
 791 
 792 
 793 int Deoptimization::deoptimize_dependents() {
 794   Threads::deoptimized_wrt_marked_nmethods();
 795   return 0;
 796 }
 797 
 798 Deoptimization::DeoptAction Deoptimization::_unloaded_action
 799   = Deoptimization::Action_reinterpret;
 800 
 801 #if defined(COMPILER2) || INCLUDE_JVMCI
 802 bool Deoptimization::realloc_objects(JavaThread* thread, frame* fr, GrowableArray<ScopeValue*>* objects, TRAPS) {
 803   Handle pending_exception(THREAD, thread->pending_exception());
 804   const char* exception_file = thread->exception_file();
 805   int exception_line = thread->exception_line();
 806   thread->clear_pending_exception();
 807 
 808   bool failures = false;
 809 
 810   for (int i = 0; i < objects->length(); i++) {
 811     assert(objects->at(i)->is_object(), "invalid debug information");
 812     ObjectValue* sv = (ObjectValue*) objects->at(i);
 813 
 814     Klass* k = java_lang_Class::as_Klass(sv->klass()->as_ConstantOopReadValue()->value()());
 815     oop obj = NULL;
 816 
 817     if (k->is_instance_klass()) {
 818       InstanceKlass* ik = InstanceKlass::cast(k);
 819       obj = ik->allocate_instance(THREAD);
 820     } else if (k->is_typeArray_klass()) {
 821       TypeArrayKlass* ak = TypeArrayKlass::cast(k);
 822       assert(sv->field_size() % type2size[ak->element_type()] == 0, "non-integral array length");
 823       int len = sv->field_size() / type2size[ak->element_type()];
 824       obj = ak->allocate(len, THREAD);
 825     } else if (k->is_objArray_klass()) {
 826       ObjArrayKlass* ak = ObjArrayKlass::cast(k);
 827       obj = ak->allocate(sv->field_size(), THREAD);
 828     }
 829 
 830     if (obj == NULL) {
 831       failures = true;
 832     }
 833 
 834     assert(sv->value().is_null(), "redundant reallocation");
 835     assert(obj != NULL || HAS_PENDING_EXCEPTION, "allocation should succeed or we should get an exception");
 836     CLEAR_PENDING_EXCEPTION;
 837     sv->set_value(obj);
 838   }
 839 
 840   if (failures) {
 841     THROW_OOP_(Universe::out_of_memory_error_realloc_objects(), failures);
 842   } else if (pending_exception.not_null()) {
 843     thread->set_pending_exception(pending_exception(), exception_file, exception_line);
 844   }
 845 
 846   return failures;
 847 }
 848 
 849 // restore elements of an eliminated type array
 850 void Deoptimization::reassign_type_array_elements(frame* fr, RegisterMap* reg_map, ObjectValue* sv, typeArrayOop obj, BasicType type) {
 851   int index = 0;
 852   intptr_t val;
 853 
 854   for (int i = 0; i < sv->field_size(); i++) {
 855     StackValue* value = StackValue::create_stack_value(fr, reg_map, sv->field_at(i));
 856     switch(type) {
 857     case T_LONG: case T_DOUBLE: {
 858       assert(value->type() == T_INT, "Agreement.");
 859       StackValue* low =
 860         StackValue::create_stack_value(fr, reg_map, sv->field_at(++i));
 861 #ifdef _LP64
 862       jlong res = (jlong)low->get_int();
 863 #else
 864 #ifdef SPARC
 865       // For SPARC we have to swap high and low words.
 866       jlong res = jlong_from((jint)low->get_int(), (jint)value->get_int());
 867 #else
 868       jlong res = jlong_from((jint)value->get_int(), (jint)low->get_int());
 869 #endif //SPARC
 870 #endif
 871       obj->long_at_put(index, res);
 872       break;
 873     }
 874 
 875     // Have to cast to INT (32 bits) pointer to avoid little/big-endian problem.
 876     case T_INT: case T_FLOAT: { // 4 bytes.
 877       assert(value->type() == T_INT, "Agreement.");
 878       bool big_value = false;
 879       if (i + 1 < sv->field_size() && type == T_INT) {
 880         if (sv->field_at(i)->is_location()) {
 881           Location::Type type = ((LocationValue*) sv->field_at(i))->location().type();
 882           if (type == Location::dbl || type == Location::lng) {
 883             big_value = true;
 884           }
 885         } else if (sv->field_at(i)->is_constant_int()) {
 886           ScopeValue* next_scope_field = sv->field_at(i + 1);
 887           if (next_scope_field->is_constant_long() || next_scope_field->is_constant_double()) {
 888             big_value = true;
 889           }
 890         }
 891       }
 892 
 893       if (big_value) {
 894         StackValue* low = StackValue::create_stack_value(fr, reg_map, sv->field_at(++i));
 895   #ifdef _LP64
 896         jlong res = (jlong)low->get_int();
 897   #else
 898   #ifdef SPARC
 899         // For SPARC we have to swap high and low words.
 900         jlong res = jlong_from((jint)low->get_int(), (jint)value->get_int());
 901   #else
 902         jlong res = jlong_from((jint)value->get_int(), (jint)low->get_int());
 903   #endif //SPARC
 904   #endif
 905         obj->int_at_put(index, (jint)*((jint*)&res));
 906         obj->int_at_put(++index, (jint)*(((jint*)&res) + 1));
 907       } else {
 908         val = value->get_int();
 909         obj->int_at_put(index, (jint)*((jint*)&val));
 910       }
 911       break;
 912     }
 913 
 914     case T_SHORT:
 915       assert(value->type() == T_INT, "Agreement.");
 916       val = value->get_int();
 917       obj->short_at_put(index, (jshort)*((jint*)&val));
 918       break;
 919 
 920     case T_CHAR:
 921       assert(value->type() == T_INT, "Agreement.");
 922       val = value->get_int();
 923       obj->char_at_put(index, (jchar)*((jint*)&val));
 924       break;
 925 
 926     case T_BYTE:
 927       assert(value->type() == T_INT, "Agreement.");
 928       val = value->get_int();
 929       obj->byte_at_put(index, (jbyte)*((jint*)&val));
 930       break;
 931 
 932     case T_BOOLEAN:
 933       assert(value->type() == T_INT, "Agreement.");
 934       val = value->get_int();
 935       obj->bool_at_put(index, (jboolean)*((jint*)&val));
 936       break;
 937 
 938       default:
 939         ShouldNotReachHere();
 940     }
 941     index++;
 942   }
 943 }
 944 
 945 
 946 // restore fields of an eliminated object array
 947 void Deoptimization::reassign_object_array_elements(frame* fr, RegisterMap* reg_map, ObjectValue* sv, objArrayOop obj) {
 948   for (int i = 0; i < sv->field_size(); i++) {
 949     StackValue* value = StackValue::create_stack_value(fr, reg_map, sv->field_at(i));
 950     assert(value->type() == T_OBJECT, "object element expected");
 951     obj->obj_at_put(i, value->get_obj()());
 952   }
 953 }
 954 
 955 class ReassignedField {
 956 public:
 957   int _offset;
 958   BasicType _type;
 959 public:
 960   ReassignedField() {
 961     _offset = 0;
 962     _type = T_ILLEGAL;
 963   }
 964 };
 965 
 966 int compare(ReassignedField* left, ReassignedField* right) {
 967   return left->_offset - right->_offset;
 968 }
 969 
 970 // Restore fields of an eliminated instance object using the same field order
 971 // returned by HotSpotResolvedObjectTypeImpl.getInstanceFields(true)
 972 static int reassign_fields_by_klass(InstanceKlass* klass, frame* fr, RegisterMap* reg_map, ObjectValue* sv, int svIndex, oop obj, bool skip_internal) {
 973   if (klass->superklass() != NULL) {
 974     svIndex = reassign_fields_by_klass(klass->superklass(), fr, reg_map, sv, svIndex, obj, skip_internal);
 975   }
 976 
 977   GrowableArray<ReassignedField>* fields = new GrowableArray<ReassignedField>();
 978   for (AllFieldStream fs(klass); !fs.done(); fs.next()) {
 979     if (!fs.access_flags().is_static() && (!skip_internal || !fs.access_flags().is_internal())) {
 980       ReassignedField field;
 981       field._offset = fs.offset();
 982       field._type = FieldType::basic_type(fs.signature());
 983       fields->append(field);
 984     }
 985   }
 986   fields->sort(compare);
 987   for (int i = 0; i < fields->length(); i++) {
 988     intptr_t val;
 989     ScopeValue* scope_field = sv->field_at(svIndex);
 990     StackValue* value = StackValue::create_stack_value(fr, reg_map, scope_field);
 991     int offset = fields->at(i)._offset;
 992     BasicType type = fields->at(i)._type;
 993     switch (type) {
 994       case T_OBJECT: case T_ARRAY:
 995         assert(value->type() == T_OBJECT, "Agreement.");
 996         obj->obj_field_put(offset, value->get_obj()());
 997         break;
 998 
 999       // Have to cast to INT (32 bits) pointer to avoid little/big-endian problem.
1000       case T_INT: case T_FLOAT: { // 4 bytes.
1001         assert(value->type() == T_INT, "Agreement.");
1002         bool big_value = false;
1003         if (i+1 < fields->length() && fields->at(i+1)._type == T_INT) {
1004           if (scope_field->is_location()) {
1005             Location::Type type = ((LocationValue*) scope_field)->location().type();
1006             if (type == Location::dbl || type == Location::lng) {
1007               big_value = true;
1008             }
1009           }
1010           if (scope_field->is_constant_int()) {
1011             ScopeValue* next_scope_field = sv->field_at(svIndex + 1);
1012             if (next_scope_field->is_constant_long() || next_scope_field->is_constant_double()) {
1013               big_value = true;
1014             }
1015           }
1016         }
1017 
1018         if (big_value) {
1019           i++;
1020           assert(i < fields->length(), "second T_INT field needed");
1021           assert(fields->at(i)._type == T_INT, "T_INT field needed");
1022         } else {
1023           val = value->get_int();
1024           obj->int_field_put(offset, (jint)*((jint*)&val));
1025           break;
1026         }
1027       }
1028         /* no break */
1029 
1030       case T_LONG: case T_DOUBLE: {
1031         assert(value->type() == T_INT, "Agreement.");
1032         StackValue* low = StackValue::create_stack_value(fr, reg_map, sv->field_at(++svIndex));
1033 #ifdef _LP64
1034         jlong res = (jlong)low->get_int();
1035 #else
1036 #ifdef SPARC
1037         // For SPARC we have to swap high and low words.
1038         jlong res = jlong_from((jint)low->get_int(), (jint)value->get_int());
1039 #else
1040         jlong res = jlong_from((jint)value->get_int(), (jint)low->get_int());
1041 #endif //SPARC
1042 #endif
1043         obj->long_field_put(offset, res);
1044         break;
1045       }
1046 
1047       case T_SHORT:
1048         assert(value->type() == T_INT, "Agreement.");
1049         val = value->get_int();
1050         obj->short_field_put(offset, (jshort)*((jint*)&val));
1051         break;
1052 
1053       case T_CHAR:
1054         assert(value->type() == T_INT, "Agreement.");
1055         val = value->get_int();
1056         obj->char_field_put(offset, (jchar)*((jint*)&val));
1057         break;
1058 
1059       case T_BYTE:
1060         assert(value->type() == T_INT, "Agreement.");
1061         val = value->get_int();
1062         obj->byte_field_put(offset, (jbyte)*((jint*)&val));
1063         break;
1064 
1065       case T_BOOLEAN:
1066         assert(value->type() == T_INT, "Agreement.");
1067         val = value->get_int();
1068         obj->bool_field_put(offset, (jboolean)*((jint*)&val));
1069         break;
1070 
1071       default:
1072         ShouldNotReachHere();
1073     }
1074     svIndex++;
1075   }
1076   return svIndex;
1077 }
1078 
1079 // restore fields of all eliminated objects and arrays
1080 void Deoptimization::reassign_fields(frame* fr, RegisterMap* reg_map, GrowableArray<ScopeValue*>* objects, bool realloc_failures, bool skip_internal) {
1081   for (int i = 0; i < objects->length(); i++) {
1082     ObjectValue* sv = (ObjectValue*) objects->at(i);
1083     Klass* k = java_lang_Class::as_Klass(sv->klass()->as_ConstantOopReadValue()->value()());
1084     Handle obj = sv->value();
1085     assert(obj.not_null() || realloc_failures, "reallocation was missed");
1086     if (PrintDeoptimizationDetails) {
1087       tty->print_cr("reassign fields for object of type %s!", k->name()->as_C_string());
1088     }
1089     if (obj.is_null()) {
1090       continue;
1091     }
1092 
1093     if (k->is_instance_klass()) {
1094       InstanceKlass* ik = InstanceKlass::cast(k);
1095       reassign_fields_by_klass(ik, fr, reg_map, sv, 0, obj(), skip_internal);
1096     } else if (k->is_typeArray_klass()) {
1097       TypeArrayKlass* ak = TypeArrayKlass::cast(k);
1098       reassign_type_array_elements(fr, reg_map, sv, (typeArrayOop) obj(), ak->element_type());
1099     } else if (k->is_objArray_klass()) {
1100       reassign_object_array_elements(fr, reg_map, sv, (objArrayOop) obj());
1101     }
1102   }
1103 }
1104 
1105 
1106 // relock objects for which synchronization was eliminated
1107 void Deoptimization::relock_objects(GrowableArray<MonitorInfo*>* monitors, JavaThread* thread, bool realloc_failures) {
1108   for (int i = 0; i < monitors->length(); i++) {
1109     MonitorInfo* mon_info = monitors->at(i);
1110     if (mon_info->eliminated()) {
1111       assert(!mon_info->owner_is_scalar_replaced() || realloc_failures, "reallocation was missed");
1112       if (!mon_info->owner_is_scalar_replaced()) {
1113         Handle obj(thread, mon_info->owner());
1114         markOop mark = obj->mark();
1115         if (UseBiasedLocking && mark->has_bias_pattern()) {
1116           // New allocated objects may have the mark set to anonymously biased.
1117           // Also the deoptimized method may called methods with synchronization
1118           // where the thread-local object is bias locked to the current thread.
1119           assert(mark->is_biased_anonymously() ||
1120                  mark->biased_locker() == thread, "should be locked to current thread");
1121           // Reset mark word to unbiased prototype.
1122           markOop unbiased_prototype = markOopDesc::prototype()->set_age(mark->age());
1123           obj->set_mark(unbiased_prototype);
1124         }
1125         BasicLock* lock = mon_info->lock();
1126         ObjectSynchronizer::slow_enter(obj, lock, thread);
1127         assert(mon_info->owner()->is_locked(), "object must be locked now");
1128       }
1129     }
1130   }
1131 }
1132 
1133 
1134 #ifndef PRODUCT
1135 // print information about reallocated objects
1136 void Deoptimization::print_objects(GrowableArray<ScopeValue*>* objects, bool realloc_failures) {
1137   fieldDescriptor fd;
1138 
1139   for (int i = 0; i < objects->length(); i++) {
1140     ObjectValue* sv = (ObjectValue*) objects->at(i);
1141     Klass* k = java_lang_Class::as_Klass(sv->klass()->as_ConstantOopReadValue()->value()());
1142     Handle obj = sv->value();
1143 
1144     tty->print("     object <" INTPTR_FORMAT "> of type ", p2i(sv->value()()));
1145     k->print_value();
1146     assert(obj.not_null() || realloc_failures, "reallocation was missed");
1147     if (obj.is_null()) {
1148       tty->print(" allocation failed");
1149     } else {
1150       tty->print(" allocated (%d bytes)", obj->size() * HeapWordSize);
1151     }
1152     tty->cr();
1153 
1154     if (Verbose && !obj.is_null()) {
1155       k->oop_print_on(obj(), tty);
1156     }
1157   }
1158 }
1159 #endif
1160 #endif // COMPILER2 || INCLUDE_JVMCI
1161 
1162 vframeArray* Deoptimization::create_vframeArray(JavaThread* thread, frame fr, RegisterMap *reg_map, GrowableArray<compiledVFrame*>* chunk, bool realloc_failures) {
1163   Events::log(thread, "DEOPT PACKING pc=" INTPTR_FORMAT " sp=" INTPTR_FORMAT, p2i(fr.pc()), p2i(fr.sp()));
1164 
1165 #ifndef PRODUCT
1166   if (PrintDeoptimizationDetails) {
1167     ttyLocker ttyl;
1168     tty->print("DEOPT PACKING thread " INTPTR_FORMAT " ", p2i(thread));
1169     fr.print_on(tty);
1170     tty->print_cr("     Virtual frames (innermost first):");
1171     for (int index = 0; index < chunk->length(); index++) {
1172       compiledVFrame* vf = chunk->at(index);
1173       tty->print("       %2d - ", index);
1174       vf->print_value();
1175       int bci = chunk->at(index)->raw_bci();
1176       const char* code_name;
1177       if (bci == SynchronizationEntryBCI) {
1178         code_name = "sync entry";
1179       } else {
1180         Bytecodes::Code code = vf->method()->code_at(bci);
1181         code_name = Bytecodes::name(code);
1182       }
1183       tty->print(" - %s", code_name);
1184       tty->print_cr(" @ bci %d ", bci);
1185       if (Verbose) {
1186         vf->print();
1187         tty->cr();
1188       }
1189     }
1190   }
1191 #endif
1192 
1193   // Register map for next frame (used for stack crawl).  We capture
1194   // the state of the deopt'ing frame's caller.  Thus if we need to
1195   // stuff a C2I adapter we can properly fill in the callee-save
1196   // register locations.
1197   frame caller = fr.sender(reg_map);
1198   int frame_size = caller.sp() - fr.sp();
1199 
1200   frame sender = caller;
1201 
1202   // Since the Java thread being deoptimized will eventually adjust it's own stack,
1203   // the vframeArray containing the unpacking information is allocated in the C heap.
1204   // For Compiler1, the caller of the deoptimized frame is saved for use by unpack_frames().
1205   vframeArray* array = vframeArray::allocate(thread, frame_size, chunk, reg_map, sender, caller, fr, realloc_failures);
1206 
1207   // Compare the vframeArray to the collected vframes
1208   assert(array->structural_compare(thread, chunk), "just checking");
1209 
1210 #ifndef PRODUCT
1211   if (PrintDeoptimizationDetails) {
1212     ttyLocker ttyl;
1213     tty->print_cr("     Created vframeArray " INTPTR_FORMAT, p2i(array));
1214   }
1215 #endif // PRODUCT
1216 
1217   return array;
1218 }
1219 
1220 #if defined(COMPILER2) || INCLUDE_JVMCI
1221 void Deoptimization::pop_frames_failed_reallocs(JavaThread* thread, vframeArray* array) {
1222   // Reallocation of some scalar replaced objects failed. Record
1223   // that we need to pop all the interpreter frames for the
1224   // deoptimized compiled frame.
1225   assert(thread->frames_to_pop_failed_realloc() == 0, "missed frames to pop?");
1226   thread->set_frames_to_pop_failed_realloc(array->frames());
1227   // Unlock all monitors here otherwise the interpreter will see a
1228   // mix of locked and unlocked monitors (because of failed
1229   // reallocations of synchronized objects) and be confused.
1230   for (int i = 0; i < array->frames(); i++) {
1231     MonitorChunk* monitors = array->element(i)->monitors();
1232     if (monitors != NULL) {
1233       for (int j = 0; j < monitors->number_of_monitors(); j++) {
1234         BasicObjectLock* src = monitors->at(j);
1235         if (src->obj() != NULL) {
1236           ObjectSynchronizer::fast_exit(src->obj(), src->lock(), thread);
1237         }
1238       }
1239       array->element(i)->free_monitors(thread);
1240 #ifdef ASSERT
1241       array->element(i)->set_removed_monitors();
1242 #endif
1243     }
1244   }
1245 }
1246 #endif
1247 
1248 static void collect_monitors(compiledVFrame* cvf, GrowableArray<Handle>* objects_to_revoke) {
1249   GrowableArray<MonitorInfo*>* monitors = cvf->monitors();
1250   Thread* thread = Thread::current();
1251   for (int i = 0; i < monitors->length(); i++) {
1252     MonitorInfo* mon_info = monitors->at(i);
1253     if (!mon_info->eliminated() && mon_info->owner() != NULL) {
1254       objects_to_revoke->append(Handle(thread, mon_info->owner()));
1255     }
1256   }
1257 }
1258 
1259 
1260 void Deoptimization::revoke_biases_of_monitors(JavaThread* thread, frame fr, RegisterMap* map) {
1261   if (!UseBiasedLocking) {
1262     return;
1263   }
1264 
1265   GrowableArray<Handle>* objects_to_revoke = new GrowableArray<Handle>();
1266 
1267   // Unfortunately we don't have a RegisterMap available in most of
1268   // the places we want to call this routine so we need to walk the
1269   // stack again to update the register map.
1270   if (map == NULL || !map->update_map()) {
1271     StackFrameStream sfs(thread, true);
1272     bool found = false;
1273     while (!found && !sfs.is_done()) {
1274       frame* cur = sfs.current();
1275       sfs.next();
1276       found = cur->id() == fr.id();
1277     }
1278     assert(found, "frame to be deoptimized not found on target thread's stack");
1279     map = sfs.register_map();
1280   }
1281 
1282   vframe* vf = vframe::new_vframe(&fr, map, thread);
1283   compiledVFrame* cvf = compiledVFrame::cast(vf);
1284   // Revoke monitors' biases in all scopes
1285   while (!cvf->is_top()) {
1286     collect_monitors(cvf, objects_to_revoke);
1287     cvf = compiledVFrame::cast(cvf->sender());
1288   }
1289   collect_monitors(cvf, objects_to_revoke);
1290 
1291   if (SafepointSynchronize::is_at_safepoint()) {
1292     BiasedLocking::revoke_at_safepoint(objects_to_revoke);
1293   } else {
1294     BiasedLocking::revoke(objects_to_revoke);
1295   }
1296 }
1297 
1298 
1299 void Deoptimization::revoke_biases_of_monitors(CodeBlob* cb) {
1300   if (!UseBiasedLocking) {
1301     return;
1302   }
1303 
1304   assert(SafepointSynchronize::is_at_safepoint(), "must only be called from safepoint");
1305   GrowableArray<Handle>* objects_to_revoke = new GrowableArray<Handle>();
1306   for (JavaThread* jt = Threads::first(); jt != NULL ; jt = jt->next()) {
1307     if (jt->has_last_Java_frame()) {
1308       StackFrameStream sfs(jt, true);
1309       while (!sfs.is_done()) {
1310         frame* cur = sfs.current();
1311         if (cb->contains(cur->pc())) {
1312           vframe* vf = vframe::new_vframe(cur, sfs.register_map(), jt);
1313           compiledVFrame* cvf = compiledVFrame::cast(vf);
1314           // Revoke monitors' biases in all scopes
1315           while (!cvf->is_top()) {
1316             collect_monitors(cvf, objects_to_revoke);
1317             cvf = compiledVFrame::cast(cvf->sender());
1318           }
1319           collect_monitors(cvf, objects_to_revoke);
1320         }
1321         sfs.next();
1322       }
1323     }
1324   }
1325   BiasedLocking::revoke_at_safepoint(objects_to_revoke);
1326 }
1327 
1328 
1329 void Deoptimization::deoptimize_single_frame(JavaThread* thread, frame fr, Deoptimization::DeoptReason reason) {
1330   assert(fr.can_be_deoptimized(), "checking frame type");
1331 
1332   gather_statistics(reason, Action_none, Bytecodes::_illegal);
1333 
1334   if (LogCompilation && xtty != NULL) {
1335     CompiledMethod* cm = fr.cb()->as_compiled_method_or_null();
1336     assert(cm != NULL, "only compiled methods can deopt");
1337 
1338     ttyLocker ttyl;
1339     xtty->begin_head("deoptimized thread='" UINTX_FORMAT "' reason='%s' pc='" INTPTR_FORMAT "'",(uintx)thread->osthread()->thread_id(), trap_reason_name(reason), p2i(fr.pc()));
1340     cm->log_identity(xtty);
1341     xtty->end_head();
1342     for (ScopeDesc* sd = cm->scope_desc_at(fr.pc()); ; sd = sd->sender()) {
1343       xtty->begin_elem("jvms bci='%d'", sd->bci());
1344       xtty->method(sd->method());
1345       xtty->end_elem();
1346       if (sd->is_top())  break;
1347     }
1348     xtty->tail("deoptimized");
1349   }
1350 
1351   // Patch the compiled method so that when execution returns to it we will
1352   // deopt the execution state and return to the interpreter.
1353   fr.deoptimize(thread);
1354 }
1355 
1356 void Deoptimization::deoptimize(JavaThread* thread, frame fr, RegisterMap *map) {
1357   deoptimize(thread, fr, map, Reason_constraint);
1358 }
1359 
1360 void Deoptimization::deoptimize(JavaThread* thread, frame fr, RegisterMap *map, DeoptReason reason) {
1361   // Deoptimize only if the frame comes from compile code.
1362   // Do not deoptimize the frame which is already patched
1363   // during the execution of the loops below.
1364   if (!fr.is_compiled_frame() || fr.is_deoptimized_frame()) {
1365     return;
1366   }
1367   ResourceMark rm;
1368   DeoptimizationMarker dm;
1369   if (UseBiasedLocking) {
1370     revoke_biases_of_monitors(thread, fr, map);
1371   }
1372   deoptimize_single_frame(thread, fr, reason);
1373 
1374 }
1375 
1376 
1377 void Deoptimization::deoptimize_frame_internal(JavaThread* thread, intptr_t* id, DeoptReason reason) {
1378   assert(thread == Thread::current() || SafepointSynchronize::is_at_safepoint(),
1379          "can only deoptimize other thread at a safepoint");
1380   // Compute frame and register map based on thread and sp.
1381   RegisterMap reg_map(thread, UseBiasedLocking);
1382   frame fr = thread->last_frame();
1383   while (fr.id() != id) {
1384     fr = fr.sender(&reg_map);
1385   }
1386   deoptimize(thread, fr, &reg_map, reason);
1387 }
1388 
1389 
1390 void Deoptimization::deoptimize_frame(JavaThread* thread, intptr_t* id, DeoptReason reason) {
1391   if (thread == Thread::current()) {
1392     Deoptimization::deoptimize_frame_internal(thread, id, reason);
1393   } else {
1394     VM_DeoptimizeFrame deopt(thread, id, reason);
1395     VMThread::execute(&deopt);
1396   }
1397 }
1398 
1399 void Deoptimization::deoptimize_frame(JavaThread* thread, intptr_t* id) {
1400   deoptimize_frame(thread, id, Reason_constraint);
1401 }
1402 
1403 // JVMTI PopFrame support
1404 JRT_LEAF(void, Deoptimization::popframe_preserve_args(JavaThread* thread, int bytes_to_save, void* start_address))
1405 {
1406   thread->popframe_preserve_args(in_ByteSize(bytes_to_save), start_address);
1407 }
1408 JRT_END
1409 
1410 MethodData*
1411 Deoptimization::get_method_data(JavaThread* thread, const methodHandle& m,
1412                                 bool create_if_missing) {
1413   Thread* THREAD = thread;
1414   MethodData* mdo = m()->method_data();
1415   if (mdo == NULL && create_if_missing && !HAS_PENDING_EXCEPTION) {
1416     // Build an MDO.  Ignore errors like OutOfMemory;
1417     // that simply means we won't have an MDO to update.
1418     Method::build_interpreter_method_data(m, THREAD);
1419     if (HAS_PENDING_EXCEPTION) {
1420       assert((PENDING_EXCEPTION->is_a(SystemDictionary::OutOfMemoryError_klass())), "we expect only an OOM error here");
1421       CLEAR_PENDING_EXCEPTION;
1422     }
1423     mdo = m()->method_data();
1424   }
1425   return mdo;
1426 }
1427 
1428 #if defined(COMPILER2) || defined(SHARK) || INCLUDE_JVMCI
1429 void Deoptimization::load_class_by_index(const constantPoolHandle& constant_pool, int index, TRAPS) {
1430   // in case of an unresolved klass entry, load the class.
1431   if (constant_pool->tag_at(index).is_unresolved_klass()) {
1432     Klass* tk = constant_pool->klass_at_ignore_error(index, CHECK);
1433     return;
1434   }
1435 
1436   if (!constant_pool->tag_at(index).is_symbol()) return;
1437 
1438   Handle class_loader (THREAD, constant_pool->pool_holder()->class_loader());
1439   Symbol*  symbol  = constant_pool->symbol_at(index);
1440 
1441   // class name?
1442   if (symbol->byte_at(0) != '(') {
1443     Handle protection_domain (THREAD, constant_pool->pool_holder()->protection_domain());
1444     SystemDictionary::resolve_or_null(symbol, class_loader, protection_domain, CHECK);
1445     return;
1446   }
1447 
1448   // then it must be a signature!
1449   ResourceMark rm(THREAD);
1450   for (SignatureStream ss(symbol); !ss.is_done(); ss.next()) {
1451     if (ss.is_object()) {
1452       Symbol* class_name = ss.as_symbol(CHECK);
1453       Handle protection_domain (THREAD, constant_pool->pool_holder()->protection_domain());
1454       SystemDictionary::resolve_or_null(class_name, class_loader, protection_domain, CHECK);
1455     }
1456   }
1457 }
1458 
1459 
1460 void Deoptimization::load_class_by_index(const constantPoolHandle& constant_pool, int index) {
1461   EXCEPTION_MARK;
1462   load_class_by_index(constant_pool, index, THREAD);
1463   if (HAS_PENDING_EXCEPTION) {
1464     // Exception happened during classloading. We ignore the exception here, since it
1465     // is going to be rethrown since the current activation is going to be deoptimized and
1466     // the interpreter will re-execute the bytecode.
1467     CLEAR_PENDING_EXCEPTION;
1468     // Class loading called java code which may have caused a stack
1469     // overflow. If the exception was thrown right before the return
1470     // to the runtime the stack is no longer guarded. Reguard the
1471     // stack otherwise if we return to the uncommon trap blob and the
1472     // stack bang causes a stack overflow we crash.
1473     assert(THREAD->is_Java_thread(), "only a java thread can be here");
1474     JavaThread* thread = (JavaThread*)THREAD;
1475     bool guard_pages_enabled = thread->stack_guards_enabled();
1476     if (!guard_pages_enabled) guard_pages_enabled = thread->reguard_stack();
1477     assert(guard_pages_enabled, "stack banging in uncommon trap blob may cause crash");
1478   }
1479 }
1480 
1481 JRT_ENTRY(void, Deoptimization::uncommon_trap_inner(JavaThread* thread, jint trap_request)) {
1482   HandleMark hm;
1483 
1484   // uncommon_trap() is called at the beginning of the uncommon trap
1485   // handler. Note this fact before we start generating temporary frames
1486   // that can confuse an asynchronous stack walker. This counter is
1487   // decremented at the end of unpack_frames().
1488   thread->inc_in_deopt_handler();
1489 
1490   // We need to update the map if we have biased locking.
1491 #if INCLUDE_JVMCI
1492   // JVMCI might need to get an exception from the stack, which in turn requires the register map to be valid
1493   RegisterMap reg_map(thread, true);
1494 #else
1495   RegisterMap reg_map(thread, UseBiasedLocking);
1496 #endif
1497   frame stub_frame = thread->last_frame();
1498   frame fr = stub_frame.sender(&reg_map);
1499   // Make sure the calling nmethod is not getting deoptimized and removed
1500   // before we are done with it.
1501   nmethodLocker nl(fr.pc());
1502 
1503   // Log a message
1504   Events::log(thread, "Uncommon trap: trap_request=" PTR32_FORMAT " fr.pc=" INTPTR_FORMAT " relative=" INTPTR_FORMAT,
1505               trap_request, p2i(fr.pc()), fr.pc() - fr.cb()->code_begin());
1506 
1507   {
1508     ResourceMark rm;
1509 
1510     // Revoke biases of any monitors in the frame to ensure we can migrate them
1511     revoke_biases_of_monitors(thread, fr, &reg_map);
1512 
1513     DeoptReason reason = trap_request_reason(trap_request);
1514     DeoptAction action = trap_request_action(trap_request);
1515 #if INCLUDE_JVMCI
1516     int debug_id = trap_request_debug_id(trap_request);
1517 #endif
1518     jint unloaded_class_index = trap_request_index(trap_request); // CP idx or -1
1519 
1520     vframe*  vf  = vframe::new_vframe(&fr, &reg_map, thread);
1521     compiledVFrame* cvf = compiledVFrame::cast(vf);
1522 
1523     CompiledMethod* nm = cvf->code();
1524 
1525     ScopeDesc*      trap_scope  = cvf->scope();
1526 
1527     if (TraceDeoptimization) {
1528       ttyLocker ttyl;
1529       tty->print_cr("  bci=%d pc=" INTPTR_FORMAT ", relative_pc=" INTPTR_FORMAT ", method=%s" JVMCI_ONLY(", debug_id=%d"), trap_scope->bci(), p2i(fr.pc()), fr.pc() - nm->code_begin(), trap_scope->method()->name_and_sig_as_C_string()
1530 #if INCLUDE_JVMCI
1531           , debug_id
1532 #endif
1533           );
1534     }
1535 
1536     methodHandle    trap_method = trap_scope->method();
1537     int             trap_bci    = trap_scope->bci();
1538 #if INCLUDE_JVMCI
1539     oop speculation = thread->pending_failed_speculation();
1540     if (nm->is_compiled_by_jvmci()) {
1541       if (speculation != NULL) {
1542         oop speculation_log = nm->as_nmethod()->speculation_log();
1543         if (speculation_log != NULL) {
1544           if (TraceDeoptimization || TraceUncollectedSpeculations) {
1545             if (HotSpotSpeculationLog::lastFailed(speculation_log) != NULL) {
1546               tty->print_cr("A speculation that was not collected by the compiler is being overwritten");
1547             }
1548           }
1549           if (TraceDeoptimization) {
1550             tty->print_cr("Saving speculation to speculation log");
1551           }
1552           HotSpotSpeculationLog::set_lastFailed(speculation_log, speculation);
1553         } else {
1554           if (TraceDeoptimization) {
1555             tty->print_cr("Speculation present but no speculation log");
1556           }
1557         }
1558         thread->set_pending_failed_speculation(NULL);
1559       } else {
1560         if (TraceDeoptimization) {
1561           tty->print_cr("No speculation");
1562         }
1563       }
1564     } else {
1565       assert(speculation == NULL, "There should not be a speculation for method compiled by non-JVMCI compilers");
1566     }
1567 
1568     if (trap_bci == SynchronizationEntryBCI) {
1569       trap_bci = 0;
1570       thread->set_pending_monitorenter(true);
1571     }
1572 
1573     if (reason == Deoptimization::Reason_transfer_to_interpreter) {
1574       thread->set_pending_transfer_to_interpreter(true);
1575     }
1576 #endif
1577 
1578     Bytecodes::Code trap_bc     = trap_method->java_code_at(trap_bci);
1579     // Record this event in the histogram.
1580     gather_statistics(reason, action, trap_bc);
1581 
1582     // Ensure that we can record deopt. history:
1583     // Need MDO to record RTM code generation state.
1584     bool create_if_missing = ProfileTraps || UseCodeAging RTM_OPT_ONLY( || UseRTMLocking );
1585 
1586     methodHandle profiled_method;
1587 #if INCLUDE_JVMCI
1588     if (nm->is_compiled_by_jvmci()) {
1589       profiled_method = nm->method();
1590     } else {
1591       profiled_method = trap_method;
1592     }
1593 #else
1594     profiled_method = trap_method;
1595 #endif
1596 
1597     MethodData* trap_mdo =
1598       get_method_data(thread, profiled_method, create_if_missing);
1599 
1600     // Log a message
1601     Events::log_deopt_message(thread, "Uncommon trap: reason=%s action=%s pc=" INTPTR_FORMAT " method=%s @ %d %s",
1602                               trap_reason_name(reason), trap_action_name(action), p2i(fr.pc()),
1603                               trap_method->name_and_sig_as_C_string(), trap_bci, nm->compiler_name());
1604 
1605     // Print a bunch of diagnostics, if requested.
1606     if (TraceDeoptimization || LogCompilation) {
1607       ResourceMark rm;
1608       ttyLocker ttyl;
1609       char buf[100];
1610       if (xtty != NULL) {
1611         xtty->begin_head("uncommon_trap thread='" UINTX_FORMAT "' %s",
1612                          os::current_thread_id(),
1613                          format_trap_request(buf, sizeof(buf), trap_request));
1614         nm->log_identity(xtty);
1615       }
1616       Symbol* class_name = NULL;
1617       bool unresolved = false;
1618       if (unloaded_class_index >= 0) {
1619         constantPoolHandle constants (THREAD, trap_method->constants());
1620         if (constants->tag_at(unloaded_class_index).is_unresolved_klass()) {
1621           class_name = constants->klass_name_at(unloaded_class_index);
1622           unresolved = true;
1623           if (xtty != NULL)
1624             xtty->print(" unresolved='1'");
1625         } else if (constants->tag_at(unloaded_class_index).is_symbol()) {
1626           class_name = constants->symbol_at(unloaded_class_index);
1627         }
1628         if (xtty != NULL)
1629           xtty->name(class_name);
1630       }
1631       if (xtty != NULL && trap_mdo != NULL && (int)reason < (int)MethodData::_trap_hist_limit) {
1632         // Dump the relevant MDO state.
1633         // This is the deopt count for the current reason, any previous
1634         // reasons or recompiles seen at this point.
1635         int dcnt = trap_mdo->trap_count(reason);
1636         if (dcnt != 0)
1637           xtty->print(" count='%d'", dcnt);
1638         ProfileData* pdata = trap_mdo->bci_to_data(trap_bci);
1639         int dos = (pdata == NULL)? 0: pdata->trap_state();
1640         if (dos != 0) {
1641           xtty->print(" state='%s'", format_trap_state(buf, sizeof(buf), dos));
1642           if (trap_state_is_recompiled(dos)) {
1643             int recnt2 = trap_mdo->overflow_recompile_count();
1644             if (recnt2 != 0)
1645               xtty->print(" recompiles2='%d'", recnt2);
1646           }
1647         }
1648       }
1649       if (xtty != NULL) {
1650         xtty->stamp();
1651         xtty->end_head();
1652       }
1653       if (TraceDeoptimization) {  // make noise on the tty
1654         tty->print("Uncommon trap occurred in");
1655         nm->method()->print_short_name(tty);
1656         tty->print(" compiler=%s compile_id=%d", nm->compiler_name(), nm->compile_id());
1657 #if INCLUDE_JVMCI
1658         if (nm->is_nmethod()) {
1659           oop installedCode = nm->as_nmethod()->jvmci_installed_code();
1660           if (installedCode != NULL) {
1661             oop installedCodeName = NULL;
1662             if (installedCode->is_a(InstalledCode::klass())) {
1663               installedCodeName = InstalledCode::name(installedCode);
1664             }
1665             if (installedCodeName != NULL) {
1666               tty->print(" (JVMCI: installedCodeName=%s) ", java_lang_String::as_utf8_string(installedCodeName));
1667             } else {
1668               tty->print(" (JVMCI: installed code has no name) ");
1669             }
1670           } else if (nm->is_compiled_by_jvmci()) {
1671             tty->print(" (JVMCI: no installed code) ");
1672           }
1673         }
1674 #endif
1675         tty->print(" (@" INTPTR_FORMAT ") thread=" UINTX_FORMAT " reason=%s action=%s unloaded_class_index=%d" JVMCI_ONLY(" debug_id=%d"),
1676                    p2i(fr.pc()),
1677                    os::current_thread_id(),
1678                    trap_reason_name(reason),
1679                    trap_action_name(action),
1680                    unloaded_class_index
1681 #if INCLUDE_JVMCI
1682                    , debug_id
1683 #endif
1684                    );
1685         if (class_name != NULL) {
1686           tty->print(unresolved ? " unresolved class: " : " symbol: ");
1687           class_name->print_symbol_on(tty);
1688         }
1689         tty->cr();
1690       }
1691       if (xtty != NULL) {
1692         // Log the precise location of the trap.
1693         for (ScopeDesc* sd = trap_scope; ; sd = sd->sender()) {
1694           xtty->begin_elem("jvms bci='%d'", sd->bci());
1695           xtty->method(sd->method());
1696           xtty->end_elem();
1697           if (sd->is_top())  break;
1698         }
1699         xtty->tail("uncommon_trap");
1700       }
1701     }
1702     // (End diagnostic printout.)
1703 
1704     // Load class if necessary
1705     if (unloaded_class_index >= 0) {
1706       constantPoolHandle constants(THREAD, trap_method->constants());
1707       load_class_by_index(constants, unloaded_class_index);
1708     }
1709 
1710     // Flush the nmethod if necessary and desirable.
1711     //
1712     // We need to avoid situations where we are re-flushing the nmethod
1713     // because of a hot deoptimization site.  Repeated flushes at the same
1714     // point need to be detected by the compiler and avoided.  If the compiler
1715     // cannot avoid them (or has a bug and "refuses" to avoid them), this
1716     // module must take measures to avoid an infinite cycle of recompilation
1717     // and deoptimization.  There are several such measures:
1718     //
1719     //   1. If a recompilation is ordered a second time at some site X
1720     //   and for the same reason R, the action is adjusted to 'reinterpret',
1721     //   to give the interpreter time to exercise the method more thoroughly.
1722     //   If this happens, the method's overflow_recompile_count is incremented.
1723     //
1724     //   2. If the compiler fails to reduce the deoptimization rate, then
1725     //   the method's overflow_recompile_count will begin to exceed the set
1726     //   limit PerBytecodeRecompilationCutoff.  If this happens, the action
1727     //   is adjusted to 'make_not_compilable', and the method is abandoned
1728     //   to the interpreter.  This is a performance hit for hot methods,
1729     //   but is better than a disastrous infinite cycle of recompilations.
1730     //   (Actually, only the method containing the site X is abandoned.)
1731     //
1732     //   3. In parallel with the previous measures, if the total number of
1733     //   recompilations of a method exceeds the much larger set limit
1734     //   PerMethodRecompilationCutoff, the method is abandoned.
1735     //   This should only happen if the method is very large and has
1736     //   many "lukewarm" deoptimizations.  The code which enforces this
1737     //   limit is elsewhere (class nmethod, class Method).
1738     //
1739     // Note that the per-BCI 'is_recompiled' bit gives the compiler one chance
1740     // to recompile at each bytecode independently of the per-BCI cutoff.
1741     //
1742     // The decision to update code is up to the compiler, and is encoded
1743     // in the Action_xxx code.  If the compiler requests Action_none
1744     // no trap state is changed, no compiled code is changed, and the
1745     // computation suffers along in the interpreter.
1746     //
1747     // The other action codes specify various tactics for decompilation
1748     // and recompilation.  Action_maybe_recompile is the loosest, and
1749     // allows the compiled code to stay around until enough traps are seen,
1750     // and until the compiler gets around to recompiling the trapping method.
1751     //
1752     // The other actions cause immediate removal of the present code.
1753 
1754     // Traps caused by injected profile shouldn't pollute trap counts.
1755     bool injected_profile_trap = trap_method->has_injected_profile() &&
1756                                  (reason == Reason_intrinsic || reason == Reason_unreached);
1757 
1758     bool update_trap_state = (reason != Reason_tenured) && !injected_profile_trap;
1759     bool make_not_entrant = false;
1760     bool make_not_compilable = false;
1761     bool reprofile = false;
1762     switch (action) {
1763     case Action_none:
1764       // Keep the old code.
1765       update_trap_state = false;
1766       break;
1767     case Action_maybe_recompile:
1768       // Do not need to invalidate the present code, but we can
1769       // initiate another
1770       // Start compiler without (necessarily) invalidating the nmethod.
1771       // The system will tolerate the old code, but new code should be
1772       // generated when possible.
1773       break;
1774     case Action_reinterpret:
1775       // Go back into the interpreter for a while, and then consider
1776       // recompiling form scratch.
1777       make_not_entrant = true;
1778       // Reset invocation counter for outer most method.
1779       // This will allow the interpreter to exercise the bytecodes
1780       // for a while before recompiling.
1781       // By contrast, Action_make_not_entrant is immediate.
1782       //
1783       // Note that the compiler will track null_check, null_assert,
1784       // range_check, and class_check events and log them as if they
1785       // had been traps taken from compiled code.  This will update
1786       // the MDO trap history so that the next compilation will
1787       // properly detect hot trap sites.
1788       reprofile = true;
1789       break;
1790     case Action_make_not_entrant:
1791       // Request immediate recompilation, and get rid of the old code.
1792       // Make them not entrant, so next time they are called they get
1793       // recompiled.  Unloaded classes are loaded now so recompile before next
1794       // time they are called.  Same for uninitialized.  The interpreter will
1795       // link the missing class, if any.
1796       make_not_entrant = true;
1797       break;
1798     case Action_make_not_compilable:
1799       // Give up on compiling this method at all.
1800       make_not_entrant = true;
1801       make_not_compilable = true;
1802       break;
1803     default:
1804       ShouldNotReachHere();
1805     }
1806 
1807     // Setting +ProfileTraps fixes the following, on all platforms:
1808     // 4852688: ProfileInterpreter is off by default for ia64.  The result is
1809     // infinite heroic-opt-uncommon-trap/deopt/recompile cycles, since the
1810     // recompile relies on a MethodData* to record heroic opt failures.
1811 
1812     // Whether the interpreter is producing MDO data or not, we also need
1813     // to use the MDO to detect hot deoptimization points and control
1814     // aggressive optimization.
1815     bool inc_recompile_count = false;
1816     ProfileData* pdata = NULL;
1817     if (ProfileTraps && !is_client_compilation_mode_vm() && update_trap_state && trap_mdo != NULL) {
1818       assert(trap_mdo == get_method_data(thread, profiled_method, false), "sanity");
1819       uint this_trap_count = 0;
1820       bool maybe_prior_trap = false;
1821       bool maybe_prior_recompile = false;
1822       pdata = query_update_method_data(trap_mdo, trap_bci, reason, true,
1823 #if INCLUDE_JVMCI
1824                                    nm->is_compiled_by_jvmci() && nm->is_osr_method(),
1825 #endif
1826                                    nm->method(),
1827                                    //outputs:
1828                                    this_trap_count,
1829                                    maybe_prior_trap,
1830                                    maybe_prior_recompile);
1831       // Because the interpreter also counts null, div0, range, and class
1832       // checks, these traps from compiled code are double-counted.
1833       // This is harmless; it just means that the PerXTrapLimit values
1834       // are in effect a little smaller than they look.
1835 
1836       DeoptReason per_bc_reason = reason_recorded_per_bytecode_if_any(reason);
1837       if (per_bc_reason != Reason_none) {
1838         // Now take action based on the partially known per-BCI history.
1839         if (maybe_prior_trap
1840             && this_trap_count >= (uint)PerBytecodeTrapLimit) {
1841           // If there are too many traps at this BCI, force a recompile.
1842           // This will allow the compiler to see the limit overflow, and
1843           // take corrective action, if possible.  The compiler generally
1844           // does not use the exact PerBytecodeTrapLimit value, but instead
1845           // changes its tactics if it sees any traps at all.  This provides
1846           // a little hysteresis, delaying a recompile until a trap happens
1847           // several times.
1848           //
1849           // Actually, since there is only one bit of counter per BCI,
1850           // the possible per-BCI counts are {0,1,(per-method count)}.
1851           // This produces accurate results if in fact there is only
1852           // one hot trap site, but begins to get fuzzy if there are
1853           // many sites.  For example, if there are ten sites each
1854           // trapping two or more times, they each get the blame for
1855           // all of their traps.
1856           make_not_entrant = true;
1857         }
1858 
1859         // Detect repeated recompilation at the same BCI, and enforce a limit.
1860         if (make_not_entrant && maybe_prior_recompile) {
1861           // More than one recompile at this point.
1862           inc_recompile_count = maybe_prior_trap;
1863         }
1864       } else {
1865         // For reasons which are not recorded per-bytecode, we simply
1866         // force recompiles unconditionally.
1867         // (Note that PerMethodRecompilationCutoff is enforced elsewhere.)
1868         make_not_entrant = true;
1869       }
1870 
1871       // Go back to the compiler if there are too many traps in this method.
1872       if (this_trap_count >= per_method_trap_limit(reason)) {
1873         // If there are too many traps in this method, force a recompile.
1874         // This will allow the compiler to see the limit overflow, and
1875         // take corrective action, if possible.
1876         // (This condition is an unlikely backstop only, because the
1877         // PerBytecodeTrapLimit is more likely to take effect first,
1878         // if it is applicable.)
1879         make_not_entrant = true;
1880       }
1881 
1882       // Here's more hysteresis:  If there has been a recompile at
1883       // this trap point already, run the method in the interpreter
1884       // for a while to exercise it more thoroughly.
1885       if (make_not_entrant && maybe_prior_recompile && maybe_prior_trap) {
1886         reprofile = true;
1887       }
1888     }
1889 
1890     // Take requested actions on the method:
1891 
1892     // Recompile
1893     if (make_not_entrant) {
1894       if (!nm->make_not_entrant()) {
1895         return; // the call did not change nmethod's state
1896       }
1897 
1898       if (pdata != NULL) {
1899         // Record the recompilation event, if any.
1900         int tstate0 = pdata->trap_state();
1901         int tstate1 = trap_state_set_recompiled(tstate0, true);
1902         if (tstate1 != tstate0)
1903           pdata->set_trap_state(tstate1);
1904       }
1905 
1906 #if INCLUDE_RTM_OPT
1907       // Restart collecting RTM locking abort statistic if the method
1908       // is recompiled for a reason other than RTM state change.
1909       // Assume that in new recompiled code the statistic could be different,
1910       // for example, due to different inlining.
1911       if ((reason != Reason_rtm_state_change) && (trap_mdo != NULL) &&
1912           UseRTMDeopt && (nm->as_nmethod()->rtm_state() != ProfileRTM)) {
1913         trap_mdo->atomic_set_rtm_state(ProfileRTM);
1914       }
1915 #endif
1916       // For code aging we count traps separately here, using make_not_entrant()
1917       // as a guard against simultaneous deopts in multiple threads.
1918       if (reason == Reason_tenured && trap_mdo != NULL) {
1919         trap_mdo->inc_tenure_traps();
1920       }
1921     }
1922 
1923     if (inc_recompile_count) {
1924       trap_mdo->inc_overflow_recompile_count();
1925       if ((uint)trap_mdo->overflow_recompile_count() >
1926           (uint)PerBytecodeRecompilationCutoff) {
1927         // Give up on the method containing the bad BCI.
1928         if (trap_method() == nm->method()) {
1929           make_not_compilable = true;
1930         } else {
1931           trap_method->set_not_compilable(CompLevel_full_optimization, true, "overflow_recompile_count > PerBytecodeRecompilationCutoff");
1932           // But give grace to the enclosing nm->method().
1933         }
1934       }
1935     }
1936 
1937     // Reprofile
1938     if (reprofile) {
1939       CompilationPolicy::policy()->reprofile(trap_scope, nm->is_osr_method());
1940     }
1941 
1942     // Give up compiling
1943     if (make_not_compilable && !nm->method()->is_not_compilable(CompLevel_full_optimization)) {
1944       assert(make_not_entrant, "consistent");
1945       nm->method()->set_not_compilable(CompLevel_full_optimization);
1946     }
1947 
1948   } // Free marked resources
1949 
1950 }
1951 JRT_END
1952 
1953 ProfileData*
1954 Deoptimization::query_update_method_data(MethodData* trap_mdo,
1955                                          int trap_bci,
1956                                          Deoptimization::DeoptReason reason,
1957                                          bool update_total_trap_count,
1958 #if INCLUDE_JVMCI
1959                                          bool is_osr,
1960 #endif
1961                                          Method* compiled_method,
1962                                          //outputs:
1963                                          uint& ret_this_trap_count,
1964                                          bool& ret_maybe_prior_trap,
1965                                          bool& ret_maybe_prior_recompile) {
1966   bool maybe_prior_trap = false;
1967   bool maybe_prior_recompile = false;
1968   uint this_trap_count = 0;
1969   if (update_total_trap_count) {
1970     uint idx = reason;
1971 #if INCLUDE_JVMCI
1972     if (is_osr) {
1973       idx += Reason_LIMIT;
1974     }
1975 #endif
1976     uint prior_trap_count = trap_mdo->trap_count(idx);
1977     this_trap_count  = trap_mdo->inc_trap_count(idx);
1978 
1979     // If the runtime cannot find a place to store trap history,
1980     // it is estimated based on the general condition of the method.
1981     // If the method has ever been recompiled, or has ever incurred
1982     // a trap with the present reason , then this BCI is assumed
1983     // (pessimistically) to be the culprit.
1984     maybe_prior_trap      = (prior_trap_count != 0);
1985     maybe_prior_recompile = (trap_mdo->decompile_count() != 0);
1986   }
1987   ProfileData* pdata = NULL;
1988 
1989 
1990   // For reasons which are recorded per bytecode, we check per-BCI data.
1991   DeoptReason per_bc_reason = reason_recorded_per_bytecode_if_any(reason);
1992   assert(per_bc_reason != Reason_none || update_total_trap_count, "must be");
1993   if (per_bc_reason != Reason_none) {
1994     // Find the profile data for this BCI.  If there isn't one,
1995     // try to allocate one from the MDO's set of spares.
1996     // This will let us detect a repeated trap at this point.
1997     pdata = trap_mdo->allocate_bci_to_data(trap_bci, reason_is_speculate(reason) ? compiled_method : NULL);
1998 
1999     if (pdata != NULL) {
2000       if (reason_is_speculate(reason) && !pdata->is_SpeculativeTrapData()) {
2001         if (LogCompilation && xtty != NULL) {
2002           ttyLocker ttyl;
2003           // no more room for speculative traps in this MDO
2004           xtty->elem("speculative_traps_oom");
2005         }
2006       }
2007       // Query the trap state of this profile datum.
2008       int tstate0 = pdata->trap_state();
2009       if (!trap_state_has_reason(tstate0, per_bc_reason))
2010         maybe_prior_trap = false;
2011       if (!trap_state_is_recompiled(tstate0))
2012         maybe_prior_recompile = false;
2013 
2014       // Update the trap state of this profile datum.
2015       int tstate1 = tstate0;
2016       // Record the reason.
2017       tstate1 = trap_state_add_reason(tstate1, per_bc_reason);
2018       // Store the updated state on the MDO, for next time.
2019       if (tstate1 != tstate0)
2020         pdata->set_trap_state(tstate1);
2021     } else {
2022       if (LogCompilation && xtty != NULL) {
2023         ttyLocker ttyl;
2024         // Missing MDP?  Leave a small complaint in the log.
2025         xtty->elem("missing_mdp bci='%d'", trap_bci);
2026       }
2027     }
2028   }
2029 
2030   // Return results:
2031   ret_this_trap_count = this_trap_count;
2032   ret_maybe_prior_trap = maybe_prior_trap;
2033   ret_maybe_prior_recompile = maybe_prior_recompile;
2034   return pdata;
2035 }
2036 
2037 void
2038 Deoptimization::update_method_data_from_interpreter(MethodData* trap_mdo, int trap_bci, int reason) {
2039   ResourceMark rm;
2040   // Ignored outputs:
2041   uint ignore_this_trap_count;
2042   bool ignore_maybe_prior_trap;
2043   bool ignore_maybe_prior_recompile;
2044   assert(!reason_is_speculate(reason), "reason speculate only used by compiler");
2045   // JVMCI uses the total counts to determine if deoptimizations are happening too frequently -> do not adjust total counts
2046   bool update_total_counts = JVMCI_ONLY(false) NOT_JVMCI(true);
2047   query_update_method_data(trap_mdo, trap_bci,
2048                            (DeoptReason)reason,
2049                            update_total_counts,
2050 #if INCLUDE_JVMCI
2051                            false,
2052 #endif
2053                            NULL,
2054                            ignore_this_trap_count,
2055                            ignore_maybe_prior_trap,
2056                            ignore_maybe_prior_recompile);
2057 }
2058 
2059 Deoptimization::UnrollBlock* Deoptimization::uncommon_trap(JavaThread* thread, jint trap_request, jint exec_mode) {
2060   if (TraceDeoptimization) {
2061     tty->print("Uncommon trap ");
2062   }
2063   // Still in Java no safepoints
2064   {
2065     // This enters VM and may safepoint
2066     uncommon_trap_inner(thread, trap_request);
2067   }
2068   return fetch_unroll_info_helper(thread, exec_mode);
2069 }
2070 
2071 // Local derived constants.
2072 // Further breakdown of DataLayout::trap_state, as promised by DataLayout.
2073 const int DS_REASON_MASK   = DataLayout::trap_mask >> 1;
2074 const int DS_RECOMPILE_BIT = DataLayout::trap_mask - DS_REASON_MASK;
2075 
2076 //---------------------------trap_state_reason---------------------------------
2077 Deoptimization::DeoptReason
2078 Deoptimization::trap_state_reason(int trap_state) {
2079   // This assert provides the link between the width of DataLayout::trap_bits
2080   // and the encoding of "recorded" reasons.  It ensures there are enough
2081   // bits to store all needed reasons in the per-BCI MDO profile.
2082   assert(DS_REASON_MASK >= Reason_RECORDED_LIMIT, "enough bits");
2083   int recompile_bit = (trap_state & DS_RECOMPILE_BIT);
2084   trap_state -= recompile_bit;
2085   if (trap_state == DS_REASON_MASK) {
2086     return Reason_many;
2087   } else {
2088     assert((int)Reason_none == 0, "state=0 => Reason_none");
2089     return (DeoptReason)trap_state;
2090   }
2091 }
2092 //-------------------------trap_state_has_reason-------------------------------
2093 int Deoptimization::trap_state_has_reason(int trap_state, int reason) {
2094   assert(reason_is_recorded_per_bytecode((DeoptReason)reason), "valid reason");
2095   assert(DS_REASON_MASK >= Reason_RECORDED_LIMIT, "enough bits");
2096   int recompile_bit = (trap_state & DS_RECOMPILE_BIT);
2097   trap_state -= recompile_bit;
2098   if (trap_state == DS_REASON_MASK) {
2099     return -1;  // true, unspecifically (bottom of state lattice)
2100   } else if (trap_state == reason) {
2101     return 1;   // true, definitely
2102   } else if (trap_state == 0) {
2103     return 0;   // false, definitely (top of state lattice)
2104   } else {
2105     return 0;   // false, definitely
2106   }
2107 }
2108 //-------------------------trap_state_add_reason-------------------------------
2109 int Deoptimization::trap_state_add_reason(int trap_state, int reason) {
2110   assert(reason_is_recorded_per_bytecode((DeoptReason)reason) || reason == Reason_many, "valid reason");
2111   int recompile_bit = (trap_state & DS_RECOMPILE_BIT);
2112   trap_state -= recompile_bit;
2113   if (trap_state == DS_REASON_MASK) {
2114     return trap_state + recompile_bit;     // already at state lattice bottom
2115   } else if (trap_state == reason) {
2116     return trap_state + recompile_bit;     // the condition is already true
2117   } else if (trap_state == 0) {
2118     return reason + recompile_bit;          // no condition has yet been true
2119   } else {
2120     return DS_REASON_MASK + recompile_bit;  // fall to state lattice bottom
2121   }
2122 }
2123 //-----------------------trap_state_is_recompiled------------------------------
2124 bool Deoptimization::trap_state_is_recompiled(int trap_state) {
2125   return (trap_state & DS_RECOMPILE_BIT) != 0;
2126 }
2127 //-----------------------trap_state_set_recompiled-----------------------------
2128 int Deoptimization::trap_state_set_recompiled(int trap_state, bool z) {
2129   if (z)  return trap_state |  DS_RECOMPILE_BIT;
2130   else    return trap_state & ~DS_RECOMPILE_BIT;
2131 }
2132 //---------------------------format_trap_state---------------------------------
2133 // This is used for debugging and diagnostics, including LogFile output.
2134 const char* Deoptimization::format_trap_state(char* buf, size_t buflen,
2135                                               int trap_state) {
2136   assert(buflen > 0, "sanity");
2137   DeoptReason reason      = trap_state_reason(trap_state);
2138   bool        recomp_flag = trap_state_is_recompiled(trap_state);
2139   // Re-encode the state from its decoded components.
2140   int decoded_state = 0;
2141   if (reason_is_recorded_per_bytecode(reason) || reason == Reason_many)
2142     decoded_state = trap_state_add_reason(decoded_state, reason);
2143   if (recomp_flag)
2144     decoded_state = trap_state_set_recompiled(decoded_state, recomp_flag);
2145   // If the state re-encodes properly, format it symbolically.
2146   // Because this routine is used for debugging and diagnostics,
2147   // be robust even if the state is a strange value.
2148   size_t len;
2149   if (decoded_state != trap_state) {
2150     // Random buggy state that doesn't decode??
2151     len = jio_snprintf(buf, buflen, "#%d", trap_state);
2152   } else {
2153     len = jio_snprintf(buf, buflen, "%s%s",
2154                        trap_reason_name(reason),
2155                        recomp_flag ? " recompiled" : "");
2156   }
2157   return buf;
2158 }
2159 
2160 
2161 //--------------------------------statics--------------------------------------
2162 const char* Deoptimization::_trap_reason_name[] = {
2163   // Note:  Keep this in sync. with enum DeoptReason.
2164   "none",
2165   "null_check",
2166   "null_assert" JVMCI_ONLY("_or_unreached0"),
2167   "range_check",
2168   "class_check",
2169   "array_check",
2170   "intrinsic" JVMCI_ONLY("_or_type_checked_inlining"),
2171   "bimorphic" JVMCI_ONLY("_or_optimized_type_check"),
2172   "unloaded",
2173   "uninitialized",
2174   "unreached",
2175   "unhandled",
2176   "constraint",
2177   "div0_check",
2178   "age",
2179   "predicate",
2180   "loop_limit_check",
2181   "speculate_class_check",
2182   "speculate_null_check",
2183   "speculate_null_assert",
2184   "rtm_state_change",
2185   "unstable_if",
2186   "unstable_fused_if",
2187 #if INCLUDE_JVMCI
2188   "aliasing",
2189   "transfer_to_interpreter",
2190   "not_compiled_exception_handler",
2191   "unresolved",
2192   "jsr_mismatch",
2193 #endif
2194   "tenured"
2195 };
2196 const char* Deoptimization::_trap_action_name[] = {
2197   // Note:  Keep this in sync. with enum DeoptAction.
2198   "none",
2199   "maybe_recompile",
2200   "reinterpret",
2201   "make_not_entrant",
2202   "make_not_compilable"
2203 };
2204 
2205 const char* Deoptimization::trap_reason_name(int reason) {
2206   // Check that every reason has a name
2207   STATIC_ASSERT(sizeof(_trap_reason_name)/sizeof(const char*) == Reason_LIMIT);
2208 
2209   if (reason == Reason_many)  return "many";
2210   if ((uint)reason < Reason_LIMIT)
2211     return _trap_reason_name[reason];
2212   static char buf[20];
2213   sprintf(buf, "reason%d", reason);
2214   return buf;
2215 }
2216 const char* Deoptimization::trap_action_name(int action) {
2217   // Check that every action has a name
2218   STATIC_ASSERT(sizeof(_trap_action_name)/sizeof(const char*) == Action_LIMIT);
2219 
2220   if ((uint)action < Action_LIMIT)
2221     return _trap_action_name[action];
2222   static char buf[20];
2223   sprintf(buf, "action%d", action);
2224   return buf;
2225 }
2226 
2227 // This is used for debugging and diagnostics, including LogFile output.
2228 const char* Deoptimization::format_trap_request(char* buf, size_t buflen,
2229                                                 int trap_request) {
2230   jint unloaded_class_index = trap_request_index(trap_request);
2231   const char* reason = trap_reason_name(trap_request_reason(trap_request));
2232   const char* action = trap_action_name(trap_request_action(trap_request));
2233 #if INCLUDE_JVMCI
2234   int debug_id = trap_request_debug_id(trap_request);
2235 #endif
2236   size_t len;
2237   if (unloaded_class_index < 0) {
2238     len = jio_snprintf(buf, buflen, "reason='%s' action='%s'" JVMCI_ONLY(" debug_id='%d'"),
2239                        reason, action
2240 #if INCLUDE_JVMCI
2241                        ,debug_id
2242 #endif
2243                        );
2244   } else {
2245     len = jio_snprintf(buf, buflen, "reason='%s' action='%s' index='%d'" JVMCI_ONLY(" debug_id='%d'"),
2246                        reason, action, unloaded_class_index
2247 #if INCLUDE_JVMCI
2248                        ,debug_id
2249 #endif
2250                        );
2251   }
2252   return buf;
2253 }
2254 
2255 juint Deoptimization::_deoptimization_hist
2256         [Deoptimization::Reason_LIMIT]
2257     [1 + Deoptimization::Action_LIMIT]
2258         [Deoptimization::BC_CASE_LIMIT]
2259   = {0};
2260 
2261 enum {
2262   LSB_BITS = 8,
2263   LSB_MASK = right_n_bits(LSB_BITS)
2264 };
2265 
2266 void Deoptimization::gather_statistics(DeoptReason reason, DeoptAction action,
2267                                        Bytecodes::Code bc) {
2268   assert(reason >= 0 && reason < Reason_LIMIT, "oob");
2269   assert(action >= 0 && action < Action_LIMIT, "oob");
2270   _deoptimization_hist[Reason_none][0][0] += 1;  // total
2271   _deoptimization_hist[reason][0][0]      += 1;  // per-reason total
2272   juint* cases = _deoptimization_hist[reason][1+action];
2273   juint* bc_counter_addr = NULL;
2274   juint  bc_counter      = 0;
2275   // Look for an unused counter, or an exact match to this BC.
2276   if (bc != Bytecodes::_illegal) {
2277     for (int bc_case = 0; bc_case < BC_CASE_LIMIT; bc_case++) {
2278       juint* counter_addr = &cases[bc_case];
2279       juint  counter = *counter_addr;
2280       if ((counter == 0 && bc_counter_addr == NULL)
2281           || (Bytecodes::Code)(counter & LSB_MASK) == bc) {
2282         // this counter is either free or is already devoted to this BC
2283         bc_counter_addr = counter_addr;
2284         bc_counter = counter | bc;
2285       }
2286     }
2287   }
2288   if (bc_counter_addr == NULL) {
2289     // Overflow, or no given bytecode.
2290     bc_counter_addr = &cases[BC_CASE_LIMIT-1];
2291     bc_counter = (*bc_counter_addr & ~LSB_MASK);  // clear LSB
2292   }
2293   *bc_counter_addr = bc_counter + (1 << LSB_BITS);
2294 }
2295 
2296 jint Deoptimization::total_deoptimization_count() {
2297   return _deoptimization_hist[Reason_none][0][0];
2298 }
2299 
2300 jint Deoptimization::deoptimization_count(DeoptReason reason) {
2301   assert(reason >= 0 && reason < Reason_LIMIT, "oob");
2302   return _deoptimization_hist[reason][0][0];
2303 }
2304 
2305 void Deoptimization::print_statistics() {
2306   juint total = total_deoptimization_count();
2307   juint account = total;
2308   if (total != 0) {
2309     ttyLocker ttyl;
2310     if (xtty != NULL)  xtty->head("statistics type='deoptimization'");
2311     tty->print_cr("Deoptimization traps recorded:");
2312     #define PRINT_STAT_LINE(name, r) \
2313       tty->print_cr("  %4d (%4.1f%%) %s", (int)(r), ((r) * 100.0) / total, name);
2314     PRINT_STAT_LINE("total", total);
2315     // For each non-zero entry in the histogram, print the reason,
2316     // the action, and (if specifically known) the type of bytecode.
2317     for (int reason = 0; reason < Reason_LIMIT; reason++) {
2318       for (int action = 0; action < Action_LIMIT; action++) {
2319         juint* cases = _deoptimization_hist[reason][1+action];
2320         for (int bc_case = 0; bc_case < BC_CASE_LIMIT; bc_case++) {
2321           juint counter = cases[bc_case];
2322           if (counter != 0) {
2323             char name[1*K];
2324             Bytecodes::Code bc = (Bytecodes::Code)(counter & LSB_MASK);
2325             if (bc_case == BC_CASE_LIMIT && (int)bc == 0)
2326               bc = Bytecodes::_illegal;
2327             sprintf(name, "%s/%s/%s",
2328                     trap_reason_name(reason),
2329                     trap_action_name(action),
2330                     Bytecodes::is_defined(bc)? Bytecodes::name(bc): "other");
2331             juint r = counter >> LSB_BITS;
2332             tty->print_cr("  %40s: " UINT32_FORMAT " (%.1f%%)", name, r, (r * 100.0) / total);
2333             account -= r;
2334           }
2335         }
2336       }
2337     }
2338     if (account != 0) {
2339       PRINT_STAT_LINE("unaccounted", account);
2340     }
2341     #undef PRINT_STAT_LINE
2342     if (xtty != NULL)  xtty->tail("statistics");
2343   }
2344 }
2345 #else // COMPILER2 || SHARK || INCLUDE_JVMCI
2346 
2347 
2348 // Stubs for C1 only system.
2349 bool Deoptimization::trap_state_is_recompiled(int trap_state) {
2350   return false;
2351 }
2352 
2353 const char* Deoptimization::trap_reason_name(int reason) {
2354   return "unknown";
2355 }
2356 
2357 void Deoptimization::print_statistics() {
2358   // no output
2359 }
2360 
2361 void
2362 Deoptimization::update_method_data_from_interpreter(MethodData* trap_mdo, int trap_bci, int reason) {
2363   // no udpate
2364 }
2365 
2366 int Deoptimization::trap_state_has_reason(int trap_state, int reason) {
2367   return 0;
2368 }
2369 
2370 void Deoptimization::gather_statistics(DeoptReason reason, DeoptAction action,
2371                                        Bytecodes::Code bc) {
2372   // no update
2373 }
2374 
2375 const char* Deoptimization::format_trap_state(char* buf, size_t buflen,
2376                                               int trap_state) {
2377   jio_snprintf(buf, buflen, "#%d", trap_state);
2378   return buf;
2379 }
2380 
2381 #endif // COMPILER2 || SHARK || INCLUDE_JVMCI