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 "jvm.h"
  27 #include "classfile/systemDictionary.hpp"
  28 #include "code/codeCache.hpp"
  29 #include "code/debugInfoRec.hpp"
  30 #include "code/nmethod.hpp"
  31 #include "code/pcDesc.hpp"
  32 #include "code/scopeDesc.hpp"
  33 #include "interpreter/bytecode.hpp"
  34 #include "interpreter/interpreter.hpp"
  35 #include "interpreter/oopMapCache.hpp"
  36 #include "memory/allocation.inline.hpp"
  37 #include "memory/oopFactory.hpp"
  38 #include "memory/resourceArea.hpp"
  39 #include "oops/method.hpp"
  40 #include "oops/objArrayOop.inline.hpp"
  41 #include "oops/oop.inline.hpp"
  42 #include "oops/fieldStreams.hpp"
  43 #include "oops/typeArrayOop.inline.hpp"
  44 #include "oops/verifyOopClosure.hpp"
  45 #include "prims/jvmtiThreadState.hpp"
  46 #include "runtime/biasedLocking.hpp"
  47 #include "runtime/compilationPolicy.hpp"
  48 #include "runtime/deoptimization.hpp"
  49 #include "runtime/interfaceSupport.hpp"
  50 #include "runtime/sharedRuntime.hpp"
  51 #include "runtime/signature.hpp"
  52 #include "runtime/stubRoutines.hpp"
  53 #include "runtime/thread.hpp"
  54 #include "runtime/threadSMR.hpp"
  55 #include "runtime/vframe.hpp"
  56 #include "runtime/vframeArray.hpp"
  57 #include "runtime/vframe_hp.hpp"
  58 #include "utilities/events.hpp"
  59 #include "utilities/xmlstream.hpp"
  60 
  61 #if INCLUDE_JVMCI
  62 #include "jvmci/jvmciRuntime.hpp"
  63 #include "jvmci/jvmciJavaClasses.hpp"
  64 #endif
  65 
  66 
  67 bool DeoptimizationMarker::_is_active = false;
  68 
  69 Deoptimization::UnrollBlock::UnrollBlock(int  size_of_deoptimized_frame,
  70                                          int  caller_adjustment,
  71                                          int  caller_actual_parameters,
  72                                          int  number_of_frames,
  73                                          intptr_t* frame_sizes,
  74                                          address* frame_pcs,
  75                                          BasicType return_type,
  76                                          int exec_mode) {
  77   _size_of_deoptimized_frame = size_of_deoptimized_frame;
  78   _caller_adjustment         = caller_adjustment;
  79   _caller_actual_parameters  = caller_actual_parameters;
  80   _number_of_frames          = number_of_frames;
  81   _frame_sizes               = frame_sizes;
  82   _frame_pcs                 = frame_pcs;
  83   _register_block            = NEW_C_HEAP_ARRAY(intptr_t, RegisterMap::reg_count * 2, mtCompiler);
  84   _return_type               = return_type;
  85   _initial_info              = 0;
  86   // PD (x86 only)
  87   _counter_temp              = 0;
  88   _unpack_kind               = exec_mode;
  89   _sender_sp_temp            = 0;
  90 
  91   _total_frame_sizes         = size_of_frames();
  92   assert(exec_mode >= 0 && exec_mode < Unpack_LIMIT, "Unexpected exec_mode");
  93 }
  94 
  95 
  96 Deoptimization::UnrollBlock::~UnrollBlock() {
  97   FREE_C_HEAP_ARRAY(intptr_t, _frame_sizes);
  98   FREE_C_HEAP_ARRAY(intptr_t, _frame_pcs);
  99   FREE_C_HEAP_ARRAY(intptr_t, _register_block);
 100 }
 101 
 102 
 103 intptr_t* Deoptimization::UnrollBlock::value_addr_at(int register_number) const {
 104   assert(register_number < RegisterMap::reg_count, "checking register number");
 105   return &_register_block[register_number * 2];
 106 }
 107 
 108 
 109 
 110 int Deoptimization::UnrollBlock::size_of_frames() const {
 111   // Acount first for the adjustment of the initial frame
 112   int result = _caller_adjustment;
 113   for (int index = 0; index < number_of_frames(); index++) {
 114     result += frame_sizes()[index];
 115   }
 116   return result;
 117 }
 118 
 119 
 120 void Deoptimization::UnrollBlock::print() {
 121   ttyLocker ttyl;
 122   tty->print_cr("UnrollBlock");
 123   tty->print_cr("  size_of_deoptimized_frame = %d", _size_of_deoptimized_frame);
 124   tty->print(   "  frame_sizes: ");
 125   for (int index = 0; index < number_of_frames(); index++) {
 126     tty->print(INTX_FORMAT " ", frame_sizes()[index]);
 127   }
 128   tty->cr();
 129 }
 130 
 131 
 132 // In order to make fetch_unroll_info work properly with escape
 133 // analysis, The method was changed from JRT_LEAF to JRT_BLOCK_ENTRY and
 134 // ResetNoHandleMark and HandleMark were removed from it. The actual reallocation
 135 // of previously eliminated objects occurs in realloc_objects, which is
 136 // called from the method fetch_unroll_info_helper below.
 137 JRT_BLOCK_ENTRY(Deoptimization::UnrollBlock*, Deoptimization::fetch_unroll_info(JavaThread* thread, int exec_mode))
 138   // It is actually ok to allocate handles in a leaf method. It causes no safepoints,
 139   // but makes the entry a little slower. There is however a little dance we have to
 140   // do in debug mode to get around the NoHandleMark code in the JRT_LEAF macro
 141 
 142   // fetch_unroll_info() is called at the beginning of the deoptimization
 143   // handler. Note this fact before we start generating temporary frames
 144   // that can confuse an asynchronous stack walker. This counter is
 145   // decremented at the end of unpack_frames().
 146   if (TraceDeoptimization) {
 147     tty->print_cr("Deoptimizing thread " INTPTR_FORMAT, p2i(thread));
 148   }
 149   thread->inc_in_deopt_handler();
 150 
 151   return fetch_unroll_info_helper(thread, exec_mode);
 152 JRT_END
 153 
 154 
 155 // This is factored, since it is both called from a JRT_LEAF (deoptimization) and a JRT_ENTRY (uncommon_trap)
 156 Deoptimization::UnrollBlock* Deoptimization::fetch_unroll_info_helper(JavaThread* thread, int exec_mode) {
 157 
 158   // Note: there is a safepoint safety issue here. No matter whether we enter
 159   // via vanilla deopt or uncommon trap we MUST NOT stop at a safepoint once
 160   // the vframeArray is created.
 161   //
 162 
 163   // Allocate our special deoptimization ResourceMark
 164   DeoptResourceMark* dmark = new DeoptResourceMark(thread);
 165   assert(thread->deopt_mark() == NULL, "Pending deopt!");
 166   thread->set_deopt_mark(dmark);
 167 
 168   frame stub_frame = thread->last_frame(); // Makes stack walkable as side effect
 169   RegisterMap map(thread, true);
 170   RegisterMap dummy_map(thread, false);
 171   // Now get the deoptee with a valid map
 172   frame deoptee = stub_frame.sender(&map);
 173   // Set the deoptee nmethod
 174   assert(thread->deopt_compiled_method() == NULL, "Pending deopt!");
 175   CompiledMethod* cm = deoptee.cb()->as_compiled_method_or_null();
 176   thread->set_deopt_compiled_method(cm);
 177 
 178   if (VerifyStack) {
 179     thread->validate_frame_layout();
 180   }
 181 
 182   // Create a growable array of VFrames where each VFrame represents an inlined
 183   // Java frame.  This storage is allocated with the usual system arena.
 184   assert(deoptee.is_compiled_frame(), "Wrong frame type");
 185   GrowableArray<compiledVFrame*>* chunk = new GrowableArray<compiledVFrame*>(10);
 186   vframe* vf = vframe::new_vframe(&deoptee, &map, thread);
 187   while (!vf->is_top()) {
 188     assert(vf->is_compiled_frame(), "Wrong frame type");
 189     chunk->push(compiledVFrame::cast(vf));
 190     vf = vf->sender();
 191   }
 192   assert(vf->is_compiled_frame(), "Wrong frame type");
 193   chunk->push(compiledVFrame::cast(vf));
 194 
 195   bool realloc_failures = false;
 196 
 197 #if COMPILER2_OR_JVMCI
 198   // Reallocate the non-escaping objects and restore their fields. Then
 199   // relock objects if synchronization on them was eliminated.
 200 #ifndef INCLUDE_JVMCI
 201   if (DoEscapeAnalysis || EliminateNestedLocks) {
 202     if (EliminateAllocations) {
 203 #endif // INCLUDE_JVMCI
 204       assert (chunk->at(0)->scope() != NULL,"expect only compiled java frames");
 205       GrowableArray<ScopeValue*>* objects = chunk->at(0)->scope()->objects();
 206 
 207       // The flag return_oop() indicates call sites which return oop
 208       // in compiled code. Such sites include java method calls,
 209       // runtime calls (for example, used to allocate new objects/arrays
 210       // on slow code path) and any other calls generated in compiled code.
 211       // It is not guaranteed that we can get such information here only
 212       // by analyzing bytecode in deoptimized frames. This is why this flag
 213       // is set during method compilation (see Compile::Process_OopMap_Node()).
 214       // If the previous frame was popped or if we are dispatching an exception,
 215       // we don't have an oop result.
 216       bool save_oop_result = chunk->at(0)->scope()->return_oop() && !thread->popframe_forcing_deopt_reexecution() && (exec_mode == Unpack_deopt);
 217       Handle return_value;
 218       if (save_oop_result) {
 219         // Reallocation may trigger GC. If deoptimization happened on return from
 220         // call which returns oop we need to save it since it is not in oopmap.
 221         oop result = deoptee.saved_oop_result(&map);
 222         assert(oopDesc::is_oop_or_null(result), "must be oop");
 223         return_value = Handle(thread, result);
 224         assert(Universe::heap()->is_in_or_null(result), "must be heap pointer");
 225         if (TraceDeoptimization) {
 226           ttyLocker ttyl;
 227           tty->print_cr("SAVED OOP RESULT " INTPTR_FORMAT " in thread " INTPTR_FORMAT, p2i(result), p2i(thread));
 228         }
 229       }
 230       if (objects != NULL) {
 231         JRT_BLOCK
 232           realloc_failures = realloc_objects(thread, &deoptee, objects, THREAD);
 233         JRT_END
 234         bool skip_internal = (cm != NULL) && !cm->is_compiled_by_jvmci();
 235         reassign_fields(&deoptee, &map, objects, realloc_failures, skip_internal);
 236 #ifndef PRODUCT
 237         if (TraceDeoptimization) {
 238           ttyLocker ttyl;
 239           tty->print_cr("REALLOC OBJECTS in thread " INTPTR_FORMAT, p2i(thread));
 240           print_objects(objects, realloc_failures);
 241         }
 242 #endif
 243       }
 244       if (save_oop_result) {
 245         // Restore result.
 246         deoptee.set_saved_oop_result(&map, return_value());
 247       }
 248 #ifndef INCLUDE_JVMCI
 249     }
 250     if (EliminateLocks) {
 251 #endif // INCLUDE_JVMCI
 252 #ifndef PRODUCT
 253       bool first = true;
 254 #endif
 255       for (int i = 0; i < chunk->length(); i++) {
 256         compiledVFrame* cvf = chunk->at(i);
 257         assert (cvf->scope() != NULL,"expect only compiled java frames");
 258         GrowableArray<MonitorInfo*>* monitors = cvf->monitors();
 259         if (monitors->is_nonempty()) {
 260           relock_objects(monitors, thread, realloc_failures);
 261 #ifndef PRODUCT
 262           if (PrintDeoptimizationDetails) {
 263             ttyLocker ttyl;
 264             for (int j = 0; j < monitors->length(); j++) {
 265               MonitorInfo* mi = monitors->at(j);
 266               if (mi->eliminated()) {
 267                 if (first) {
 268                   first = false;
 269                   tty->print_cr("RELOCK OBJECTS in thread " INTPTR_FORMAT, p2i(thread));
 270                 }
 271                 if (mi->owner_is_scalar_replaced()) {
 272                   Klass* k = java_lang_Class::as_Klass(mi->owner_klass());
 273                   tty->print_cr("     failed reallocation for klass %s", k->external_name());
 274                 } else {
 275                   tty->print_cr("     object <" INTPTR_FORMAT "> locked", p2i(mi->owner()));
 276                 }
 277               }
 278             }
 279           }
 280 #endif // !PRODUCT
 281         }
 282       }
 283 #ifndef INCLUDE_JVMCI
 284     }
 285   }
 286 #endif // INCLUDE_JVMCI
 287 #endif // COMPILER2_OR_JVMCI
 288 
 289   ScopeDesc* trap_scope = chunk->at(0)->scope();
 290   Handle exceptionObject;
 291   if (trap_scope->rethrow_exception()) {
 292     if (PrintDeoptimizationDetails) {
 293       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());
 294     }
 295     GrowableArray<ScopeValue*>* expressions = trap_scope->expressions();
 296     guarantee(expressions != NULL && expressions->length() > 0, "must have exception to throw");
 297     ScopeValue* topOfStack = expressions->top();
 298     exceptionObject = StackValue::create_stack_value(&deoptee, &map, topOfStack)->get_obj();
 299     guarantee(exceptionObject() != NULL, "exception oop can not be null");
 300   }
 301 
 302   // Ensure that no safepoint is taken after pointers have been stored
 303   // in fields of rematerialized objects.  If a safepoint occurs from here on
 304   // out the java state residing in the vframeArray will be missed.
 305   NoSafepointVerifier no_safepoint;
 306 
 307   vframeArray* array = create_vframeArray(thread, deoptee, &map, chunk, realloc_failures);
 308 #if COMPILER2_OR_JVMCI
 309   if (realloc_failures) {
 310     pop_frames_failed_reallocs(thread, array);
 311   }
 312 #endif
 313 
 314   assert(thread->vframe_array_head() == NULL, "Pending deopt!");
 315   thread->set_vframe_array_head(array);
 316 
 317   // Now that the vframeArray has been created if we have any deferred local writes
 318   // added by jvmti then we can free up that structure as the data is now in the
 319   // vframeArray
 320 
 321   if (thread->deferred_locals() != NULL) {
 322     GrowableArray<jvmtiDeferredLocalVariableSet*>* list = thread->deferred_locals();
 323     int i = 0;
 324     do {
 325       // Because of inlining we could have multiple vframes for a single frame
 326       // and several of the vframes could have deferred writes. Find them all.
 327       if (list->at(i)->id() == array->original().id()) {
 328         jvmtiDeferredLocalVariableSet* dlv = list->at(i);
 329         list->remove_at(i);
 330         // individual jvmtiDeferredLocalVariableSet are CHeapObj's
 331         delete dlv;
 332       } else {
 333         i++;
 334       }
 335     } while ( i < list->length() );
 336     if (list->length() == 0) {
 337       thread->set_deferred_locals(NULL);
 338       // free the list and elements back to C heap.
 339       delete list;
 340     }
 341 
 342   }
 343 
 344   // Compute the caller frame based on the sender sp of stub_frame and stored frame sizes info.
 345   CodeBlob* cb = stub_frame.cb();
 346   // Verify we have the right vframeArray
 347   assert(cb->frame_size() >= 0, "Unexpected frame size");
 348   intptr_t* unpack_sp = stub_frame.sp() + cb->frame_size();
 349 
 350   // If the deopt call site is a MethodHandle invoke call site we have
 351   // to adjust the unpack_sp.
 352   nmethod* deoptee_nm = deoptee.cb()->as_nmethod_or_null();
 353   if (deoptee_nm != NULL && deoptee_nm->is_method_handle_return(deoptee.pc()))
 354     unpack_sp = deoptee.unextended_sp();
 355 
 356 #ifdef ASSERT
 357   assert(cb->is_deoptimization_stub() ||
 358          cb->is_uncommon_trap_stub() ||
 359          strcmp("Stub<DeoptimizationStub.deoptimizationHandler>", cb->name()) == 0 ||
 360          strcmp("Stub<UncommonTrapStub.uncommonTrapHandler>", cb->name()) == 0,
 361          "unexpected code blob: %s", cb->name());
 362 #endif
 363 
 364   // This is a guarantee instead of an assert because if vframe doesn't match
 365   // we will unpack the wrong deoptimized frame and wind up in strange places
 366   // where it will be very difficult to figure out what went wrong. Better
 367   // to die an early death here than some very obscure death later when the
 368   // trail is cold.
 369   // Note: on ia64 this guarantee can be fooled by frames with no memory stack
 370   // in that it will fail to detect a problem when there is one. This needs
 371   // more work in tiger timeframe.
 372   guarantee(array->unextended_sp() == unpack_sp, "vframe_array_head must contain the vframeArray to unpack");
 373 
 374   int number_of_frames = array->frames();
 375 
 376   // Compute the vframes' sizes.  Note that frame_sizes[] entries are ordered from outermost to innermost
 377   // virtual activation, which is the reverse of the elements in the vframes array.
 378   intptr_t* frame_sizes = NEW_C_HEAP_ARRAY(intptr_t, number_of_frames, mtCompiler);
 379   // +1 because we always have an interpreter return address for the final slot.
 380   address* frame_pcs = NEW_C_HEAP_ARRAY(address, number_of_frames + 1, mtCompiler);
 381   int popframe_extra_args = 0;
 382   // Create an interpreter return address for the stub to use as its return
 383   // address so the skeletal frames are perfectly walkable
 384   frame_pcs[number_of_frames] = Interpreter::deopt_entry(vtos, 0);
 385 
 386   // PopFrame requires that the preserved incoming arguments from the recently-popped topmost
 387   // activation be put back on the expression stack of the caller for reexecution
 388   if (JvmtiExport::can_pop_frame() && thread->popframe_forcing_deopt_reexecution()) {
 389     popframe_extra_args = in_words(thread->popframe_preserved_args_size_in_words());
 390   }
 391 
 392   // Find the current pc for sender of the deoptee. Since the sender may have been deoptimized
 393   // itself since the deoptee vframeArray was created we must get a fresh value of the pc rather
 394   // than simply use array->sender.pc(). This requires us to walk the current set of frames
 395   //
 396   frame deopt_sender = stub_frame.sender(&dummy_map); // First is the deoptee frame
 397   deopt_sender = deopt_sender.sender(&dummy_map);     // Now deoptee caller
 398 
 399   // It's possible that the number of parameters at the call site is
 400   // different than number of arguments in the callee when method
 401   // handles are used.  If the caller is interpreted get the real
 402   // value so that the proper amount of space can be added to it's
 403   // frame.
 404   bool caller_was_method_handle = false;
 405   if (deopt_sender.is_interpreted_frame()) {
 406     methodHandle method = deopt_sender.interpreter_frame_method();
 407     Bytecode_invoke cur = Bytecode_invoke_check(method, deopt_sender.interpreter_frame_bci());
 408     if (cur.is_invokedynamic() || cur.is_invokehandle()) {
 409       // Method handle invokes may involve fairly arbitrary chains of
 410       // calls so it's impossible to know how much actual space the
 411       // caller has for locals.
 412       caller_was_method_handle = true;
 413     }
 414   }
 415 
 416   //
 417   // frame_sizes/frame_pcs[0] oldest frame (int or c2i)
 418   // frame_sizes/frame_pcs[1] next oldest frame (int)
 419   // frame_sizes/frame_pcs[n] youngest frame (int)
 420   //
 421   // Now a pc in frame_pcs is actually the return address to the frame's caller (a frame
 422   // owns the space for the return address to it's caller).  Confusing ain't it.
 423   //
 424   // The vframe array can address vframes with indices running from
 425   // 0.._frames-1. Index  0 is the youngest frame and _frame - 1 is the oldest (root) frame.
 426   // When we create the skeletal frames we need the oldest frame to be in the zero slot
 427   // in the frame_sizes/frame_pcs so the assembly code can do a trivial walk.
 428   // so things look a little strange in this loop.
 429   //
 430   int callee_parameters = 0;
 431   int callee_locals = 0;
 432   for (int index = 0; index < array->frames(); index++ ) {
 433     // frame[number_of_frames - 1 ] = on_stack_size(youngest)
 434     // frame[number_of_frames - 2 ] = on_stack_size(sender(youngest))
 435     // frame[number_of_frames - 3 ] = on_stack_size(sender(sender(youngest)))
 436     frame_sizes[number_of_frames - 1 - index] = BytesPerWord * array->element(index)->on_stack_size(callee_parameters,
 437                                                                                                     callee_locals,
 438                                                                                                     index == 0,
 439                                                                                                     popframe_extra_args);
 440     // This pc doesn't have to be perfect just good enough to identify the frame
 441     // as interpreted so the skeleton frame will be walkable
 442     // The correct pc will be set when the skeleton frame is completely filled out
 443     // The final pc we store in the loop is wrong and will be overwritten below
 444     frame_pcs[number_of_frames - 1 - index ] = Interpreter::deopt_entry(vtos, 0) - frame::pc_return_offset;
 445 
 446     callee_parameters = array->element(index)->method()->size_of_parameters();
 447     callee_locals = array->element(index)->method()->max_locals();
 448     popframe_extra_args = 0;
 449   }
 450 
 451   // Compute whether the root vframe returns a float or double value.
 452   BasicType return_type;
 453   {
 454     methodHandle method(thread, array->element(0)->method());
 455     Bytecode_invoke invoke = Bytecode_invoke_check(method, array->element(0)->bci());
 456     return_type = invoke.is_valid() ? invoke.result_type() : T_ILLEGAL;
 457   }
 458 
 459   // Compute information for handling adapters and adjusting the frame size of the caller.
 460   int caller_adjustment = 0;
 461 
 462   // Compute the amount the oldest interpreter frame will have to adjust
 463   // its caller's stack by. If the caller is a compiled frame then
 464   // we pretend that the callee has no parameters so that the
 465   // extension counts for the full amount of locals and not just
 466   // locals-parms. This is because without a c2i adapter the parm
 467   // area as created by the compiled frame will not be usable by
 468   // the interpreter. (Depending on the calling convention there
 469   // may not even be enough space).
 470 
 471   // QQQ I'd rather see this pushed down into last_frame_adjust
 472   // and have it take the sender (aka caller).
 473 
 474   if (deopt_sender.is_compiled_frame() || caller_was_method_handle) {
 475     caller_adjustment = last_frame_adjust(0, callee_locals);
 476   } else if (callee_locals > callee_parameters) {
 477     // The caller frame may need extending to accommodate
 478     // non-parameter locals of the first unpacked interpreted frame.
 479     // Compute that adjustment.
 480     caller_adjustment = last_frame_adjust(callee_parameters, callee_locals);
 481   }
 482 
 483   // If the sender is deoptimized the we must retrieve the address of the handler
 484   // since the frame will "magically" show the original pc before the deopt
 485   // and we'd undo the deopt.
 486 
 487   frame_pcs[0] = deopt_sender.raw_pc();
 488 
 489   assert(CodeCache::find_blob_unsafe(frame_pcs[0]) != NULL, "bad pc");
 490 
 491 #ifdef INCLUDE_JVMCI
 492   if (exceptionObject() != NULL) {
 493     thread->set_exception_oop(exceptionObject());
 494     exec_mode = Unpack_exception;
 495   }
 496 #endif
 497 
 498   if (thread->frames_to_pop_failed_realloc() > 0 && exec_mode != Unpack_uncommon_trap) {
 499     assert(thread->has_pending_exception(), "should have thrown OOME");
 500     thread->set_exception_oop(thread->pending_exception());
 501     thread->clear_pending_exception();
 502     exec_mode = Unpack_exception;
 503   }
 504 
 505 #if INCLUDE_JVMCI
 506   if (thread->frames_to_pop_failed_realloc() > 0) {
 507     thread->set_pending_monitorenter(false);
 508   }
 509 #endif
 510 
 511   UnrollBlock* info = new UnrollBlock(array->frame_size() * BytesPerWord,
 512                                       caller_adjustment * BytesPerWord,
 513                                       caller_was_method_handle ? 0 : callee_parameters,
 514                                       number_of_frames,
 515                                       frame_sizes,
 516                                       frame_pcs,
 517                                       return_type,
 518                                       exec_mode);
 519   // On some platforms, we need a way to pass some platform dependent
 520   // information to the unpacking code so the skeletal frames come out
 521   // correct (initial fp value, unextended sp, ...)
 522   info->set_initial_info((intptr_t) array->sender().initial_deoptimization_info());
 523 
 524   if (array->frames() > 1) {
 525     if (VerifyStack && TraceDeoptimization) {
 526       ttyLocker ttyl;
 527       tty->print_cr("Deoptimizing method containing inlining");
 528     }
 529   }
 530 
 531   array->set_unroll_block(info);
 532   return info;
 533 }
 534 
 535 // Called to cleanup deoptimization data structures in normal case
 536 // after unpacking to stack and when stack overflow error occurs
 537 void Deoptimization::cleanup_deopt_info(JavaThread *thread,
 538                                         vframeArray *array) {
 539 
 540   // Get array if coming from exception
 541   if (array == NULL) {
 542     array = thread->vframe_array_head();
 543   }
 544   thread->set_vframe_array_head(NULL);
 545 
 546   // Free the previous UnrollBlock
 547   vframeArray* old_array = thread->vframe_array_last();
 548   thread->set_vframe_array_last(array);
 549 
 550   if (old_array != NULL) {
 551     UnrollBlock* old_info = old_array->unroll_block();
 552     old_array->set_unroll_block(NULL);
 553     delete old_info;
 554     delete old_array;
 555   }
 556 
 557   // Deallocate any resource creating in this routine and any ResourceObjs allocated
 558   // inside the vframeArray (StackValueCollections)
 559 
 560   delete thread->deopt_mark();
 561   thread->set_deopt_mark(NULL);
 562   thread->set_deopt_compiled_method(NULL);
 563 
 564 
 565   if (JvmtiExport::can_pop_frame()) {
 566 #ifndef CC_INTERP
 567     // Regardless of whether we entered this routine with the pending
 568     // popframe condition bit set, we should always clear it now
 569     thread->clear_popframe_condition();
 570 #else
 571     // C++ interpreter will clear has_pending_popframe when it enters
 572     // with method_resume. For deopt_resume2 we clear it now.
 573     if (thread->popframe_forcing_deopt_reexecution())
 574         thread->clear_popframe_condition();
 575 #endif /* CC_INTERP */
 576   }
 577 
 578   // unpack_frames() is called at the end of the deoptimization handler
 579   // and (in C2) at the end of the uncommon trap handler. Note this fact
 580   // so that an asynchronous stack walker can work again. This counter is
 581   // incremented at the beginning of fetch_unroll_info() and (in C2) at
 582   // the beginning of uncommon_trap().
 583   thread->dec_in_deopt_handler();
 584 }
 585 
 586 // Moved from cpu directories because none of the cpus has callee save values.
 587 // If a cpu implements callee save values, move this to deoptimization_<cpu>.cpp.
 588 void Deoptimization::unwind_callee_save_values(frame* f, vframeArray* vframe_array) {
 589 
 590   // This code is sort of the equivalent of C2IAdapter::setup_stack_frame back in
 591   // the days we had adapter frames. When we deoptimize a situation where a
 592   // compiled caller calls a compiled caller will have registers it expects
 593   // to survive the call to the callee. If we deoptimize the callee the only
 594   // way we can restore these registers is to have the oldest interpreter
 595   // frame that we create restore these values. That is what this routine
 596   // will accomplish.
 597 
 598   // At the moment we have modified c2 to not have any callee save registers
 599   // so this problem does not exist and this routine is just a place holder.
 600 
 601   assert(f->is_interpreted_frame(), "must be interpreted");
 602 }
 603 
 604 // Return BasicType of value being returned
 605 JRT_LEAF(BasicType, Deoptimization::unpack_frames(JavaThread* thread, int exec_mode))
 606 
 607   // We are already active in the special DeoptResourceMark any ResourceObj's we
 608   // allocate will be freed at the end of the routine.
 609 
 610   // It is actually ok to allocate handles in a leaf method. It causes no safepoints,
 611   // but makes the entry a little slower. There is however a little dance we have to
 612   // do in debug mode to get around the NoHandleMark code in the JRT_LEAF macro
 613   ResetNoHandleMark rnhm; // No-op in release/product versions
 614   HandleMark hm;
 615 
 616   frame stub_frame = thread->last_frame();
 617 
 618   // Since the frame to unpack is the top frame of this thread, the vframe_array_head
 619   // must point to the vframeArray for the unpack frame.
 620   vframeArray* array = thread->vframe_array_head();
 621 
 622 #ifndef PRODUCT
 623   if (TraceDeoptimization) {
 624     ttyLocker ttyl;
 625     tty->print_cr("DEOPT UNPACKING thread " INTPTR_FORMAT " vframeArray " INTPTR_FORMAT " mode %d",
 626                   p2i(thread), p2i(array), exec_mode);
 627   }
 628 #endif
 629   Events::log(thread, "DEOPT UNPACKING pc=" INTPTR_FORMAT " sp=" INTPTR_FORMAT " mode %d",
 630               p2i(stub_frame.pc()), p2i(stub_frame.sp()), exec_mode);
 631 
 632   UnrollBlock* info = array->unroll_block();
 633 
 634   // Unpack the interpreter frames and any adapter frame (c2 only) we might create.
 635   array->unpack_to_stack(stub_frame, exec_mode, info->caller_actual_parameters());
 636 
 637   BasicType bt = info->return_type();
 638 
 639   // If we have an exception pending, claim that the return type is an oop
 640   // so the deopt_blob does not overwrite the exception_oop.
 641 
 642   if (exec_mode == Unpack_exception)
 643     bt = T_OBJECT;
 644 
 645   // Cleanup thread deopt data
 646   cleanup_deopt_info(thread, array);
 647 
 648 #ifndef PRODUCT
 649   if (VerifyStack) {
 650     ResourceMark res_mark;
 651 
 652     thread->validate_frame_layout();
 653 
 654     // Verify that the just-unpacked frames match the interpreter's
 655     // notions of expression stack and locals
 656     vframeArray* cur_array = thread->vframe_array_last();
 657     RegisterMap rm(thread, false);
 658     rm.set_include_argument_oops(false);
 659     bool is_top_frame = true;
 660     int callee_size_of_parameters = 0;
 661     int callee_max_locals = 0;
 662     for (int i = 0; i < cur_array->frames(); i++) {
 663       vframeArrayElement* el = cur_array->element(i);
 664       frame* iframe = el->iframe();
 665       guarantee(iframe->is_interpreted_frame(), "Wrong frame type");
 666 
 667       // Get the oop map for this bci
 668       InterpreterOopMap mask;
 669       int cur_invoke_parameter_size = 0;
 670       bool try_next_mask = false;
 671       int next_mask_expression_stack_size = -1;
 672       int top_frame_expression_stack_adjustment = 0;
 673       methodHandle mh(thread, iframe->interpreter_frame_method());
 674       OopMapCache::compute_one_oop_map(mh, iframe->interpreter_frame_bci(), &mask);
 675       BytecodeStream str(mh);
 676       str.set_start(iframe->interpreter_frame_bci());
 677       int max_bci = mh->code_size();
 678       // Get to the next bytecode if possible
 679       assert(str.bci() < max_bci, "bci in interpreter frame out of bounds");
 680       // Check to see if we can grab the number of outgoing arguments
 681       // at an uncommon trap for an invoke (where the compiler
 682       // generates debug info before the invoke has executed)
 683       Bytecodes::Code cur_code = str.next();
 684       if (Bytecodes::is_invoke(cur_code)) {
 685         Bytecode_invoke invoke(mh, iframe->interpreter_frame_bci());
 686         cur_invoke_parameter_size = invoke.size_of_parameters();
 687         if (i != 0 && !invoke.is_invokedynamic() && MethodHandles::has_member_arg(invoke.klass(), invoke.name())) {
 688           callee_size_of_parameters++;
 689         }
 690       }
 691       if (str.bci() < max_bci) {
 692         Bytecodes::Code next_code = str.next();
 693         if (next_code >= 0) {
 694           // The interpreter oop map generator reports results before
 695           // the current bytecode has executed except in the case of
 696           // calls. It seems to be hard to tell whether the compiler
 697           // has emitted debug information matching the "state before"
 698           // a given bytecode or the state after, so we try both
 699           if (!Bytecodes::is_invoke(cur_code) && cur_code != Bytecodes::_athrow) {
 700             // Get expression stack size for the next bytecode
 701             if (Bytecodes::is_invoke(next_code)) {
 702               Bytecode_invoke invoke(mh, str.bci());
 703               next_mask_expression_stack_size = invoke.size_of_parameters();
 704             } else {
 705               InterpreterOopMap next_mask;
 706               OopMapCache::compute_one_oop_map(mh, str.bci(), &next_mask);
 707               next_mask_expression_stack_size = next_mask.expression_stack_size();
 708             }
 709             // Need to subtract off the size of the result type of
 710             // the bytecode because this is not described in the
 711             // debug info but returned to the interpreter in the TOS
 712             // caching register
 713             BasicType bytecode_result_type = Bytecodes::result_type(cur_code);
 714             if (bytecode_result_type != T_ILLEGAL) {
 715               top_frame_expression_stack_adjustment = type2size[bytecode_result_type];
 716             }
 717             assert(top_frame_expression_stack_adjustment >= 0, "stack adjustment must be positive");
 718             try_next_mask = true;
 719           }
 720         }
 721       }
 722 
 723       // Verify stack depth and oops in frame
 724       // This assertion may be dependent on the platform we're running on and may need modification (tested on x86 and sparc)
 725       if (!(
 726             /* SPARC */
 727             (iframe->interpreter_frame_expression_stack_size() == mask.expression_stack_size() + callee_size_of_parameters) ||
 728             /* x86 */
 729             (iframe->interpreter_frame_expression_stack_size() == mask.expression_stack_size() + callee_max_locals) ||
 730             (try_next_mask &&
 731              (iframe->interpreter_frame_expression_stack_size() == (next_mask_expression_stack_size -
 732                                                                     top_frame_expression_stack_adjustment))) ||
 733             (is_top_frame && (exec_mode == Unpack_exception) && iframe->interpreter_frame_expression_stack_size() == 0) ||
 734             (is_top_frame && (exec_mode == Unpack_uncommon_trap || exec_mode == Unpack_reexecute || el->should_reexecute()) &&
 735              (iframe->interpreter_frame_expression_stack_size() == mask.expression_stack_size() + cur_invoke_parameter_size))
 736             )) {
 737         ttyLocker ttyl;
 738 
 739         // Print out some information that will help us debug the problem
 740         tty->print_cr("Wrong number of expression stack elements during deoptimization");
 741         tty->print_cr("  Error occurred while verifying frame %d (0..%d, 0 is topmost)", i, cur_array->frames() - 1);
 742         tty->print_cr("  Fabricated interpreter frame had %d expression stack elements",
 743                       iframe->interpreter_frame_expression_stack_size());
 744         tty->print_cr("  Interpreter oop map had %d expression stack elements", mask.expression_stack_size());
 745         tty->print_cr("  try_next_mask = %d", try_next_mask);
 746         tty->print_cr("  next_mask_expression_stack_size = %d", next_mask_expression_stack_size);
 747         tty->print_cr("  callee_size_of_parameters = %d", callee_size_of_parameters);
 748         tty->print_cr("  callee_max_locals = %d", callee_max_locals);
 749         tty->print_cr("  top_frame_expression_stack_adjustment = %d", top_frame_expression_stack_adjustment);
 750         tty->print_cr("  exec_mode = %d", exec_mode);
 751         tty->print_cr("  cur_invoke_parameter_size = %d", cur_invoke_parameter_size);
 752         tty->print_cr("  Thread = " INTPTR_FORMAT ", thread ID = %d", p2i(thread), thread->osthread()->thread_id());
 753         tty->print_cr("  Interpreted frames:");
 754         for (int k = 0; k < cur_array->frames(); k++) {
 755           vframeArrayElement* el = cur_array->element(k);
 756           tty->print_cr("    %s (bci %d)", el->method()->name_and_sig_as_C_string(), el->bci());
 757         }
 758         cur_array->print_on_2(tty);
 759         guarantee(false, "wrong number of expression stack elements during deopt");
 760       }
 761       VerifyOopClosure verify;
 762       iframe->oops_interpreted_do(&verify, &rm, false);
 763       callee_size_of_parameters = mh->size_of_parameters();
 764       callee_max_locals = mh->max_locals();
 765       is_top_frame = false;
 766     }
 767   }
 768 #endif /* !PRODUCT */
 769 
 770 
 771   return bt;
 772 JRT_END
 773 
 774 
 775 int Deoptimization::deoptimize_dependents() {
 776   Threads::deoptimized_wrt_marked_nmethods();
 777   return 0;
 778 }
 779 
 780 Deoptimization::DeoptAction Deoptimization::_unloaded_action
 781   = Deoptimization::Action_reinterpret;
 782 
 783 #if COMPILER2_OR_JVMCI
 784 bool Deoptimization::realloc_objects(JavaThread* thread, frame* fr, GrowableArray<ScopeValue*>* objects, TRAPS) {
 785   Handle pending_exception(THREAD, thread->pending_exception());
 786   const char* exception_file = thread->exception_file();
 787   int exception_line = thread->exception_line();
 788   thread->clear_pending_exception();
 789 
 790   bool failures = false;
 791 
 792   for (int i = 0; i < objects->length(); i++) {
 793     assert(objects->at(i)->is_object(), "invalid debug information");
 794     ObjectValue* sv = (ObjectValue*) objects->at(i);
 795 
 796     Klass* k = java_lang_Class::as_Klass(sv->klass()->as_ConstantOopReadValue()->value()());
 797     oop obj = NULL;
 798 
 799     if (k->is_instance_klass()) {
 800       InstanceKlass* ik = InstanceKlass::cast(k);
 801       obj = ik->allocate_instance(THREAD);
 802     } else if (k->is_typeArray_klass()) {
 803       TypeArrayKlass* ak = TypeArrayKlass::cast(k);
 804       assert(sv->field_size() % type2size[ak->element_type()] == 0, "non-integral array length");
 805       int len = sv->field_size() / type2size[ak->element_type()];
 806       obj = ak->allocate(len, THREAD);
 807     } else if (k->is_objArray_klass()) {
 808       ObjArrayKlass* ak = ObjArrayKlass::cast(k);
 809       obj = ak->allocate(sv->field_size(), THREAD);
 810     }
 811 
 812     if (obj == NULL) {
 813       failures = true;
 814     }
 815 
 816     assert(sv->value().is_null(), "redundant reallocation");
 817     assert(obj != NULL || HAS_PENDING_EXCEPTION, "allocation should succeed or we should get an exception");
 818     CLEAR_PENDING_EXCEPTION;
 819     sv->set_value(obj);
 820   }
 821 
 822   if (failures) {
 823     THROW_OOP_(Universe::out_of_memory_error_realloc_objects(), failures);
 824   } else if (pending_exception.not_null()) {
 825     thread->set_pending_exception(pending_exception(), exception_file, exception_line);
 826   }
 827 
 828   return failures;
 829 }
 830 
 831 // restore elements of an eliminated type array
 832 void Deoptimization::reassign_type_array_elements(frame* fr, RegisterMap* reg_map, ObjectValue* sv, typeArrayOop obj, BasicType type) {
 833   int index = 0;
 834   intptr_t val;
 835 
 836   for (int i = 0; i < sv->field_size(); i++) {
 837     StackValue* value = StackValue::create_stack_value(fr, reg_map, sv->field_at(i));
 838     switch(type) {
 839     case T_LONG: case T_DOUBLE: {
 840       assert(value->type() == T_INT, "Agreement.");
 841       StackValue* low =
 842         StackValue::create_stack_value(fr, reg_map, sv->field_at(++i));
 843 #ifdef _LP64
 844       jlong res = (jlong)low->get_int();
 845 #else
 846 #ifdef SPARC
 847       // For SPARC we have to swap high and low words.
 848       jlong res = jlong_from((jint)low->get_int(), (jint)value->get_int());
 849 #else
 850       jlong res = jlong_from((jint)value->get_int(), (jint)low->get_int());
 851 #endif //SPARC
 852 #endif
 853       obj->long_at_put(index, res);
 854       break;
 855     }
 856 
 857     // Have to cast to INT (32 bits) pointer to avoid little/big-endian problem.
 858     case T_INT: case T_FLOAT: { // 4 bytes.
 859       assert(value->type() == T_INT, "Agreement.");
 860       bool big_value = false;
 861       if (i + 1 < sv->field_size() && type == T_INT) {
 862         if (sv->field_at(i)->is_location()) {
 863           Location::Type type = ((LocationValue*) sv->field_at(i))->location().type();
 864           if (type == Location::dbl || type == Location::lng) {
 865             big_value = true;
 866           }
 867         } else if (sv->field_at(i)->is_constant_int()) {
 868           ScopeValue* next_scope_field = sv->field_at(i + 1);
 869           if (next_scope_field->is_constant_long() || next_scope_field->is_constant_double()) {
 870             big_value = true;
 871           }
 872         }
 873       }
 874 
 875       if (big_value) {
 876         StackValue* low = StackValue::create_stack_value(fr, reg_map, sv->field_at(++i));
 877   #ifdef _LP64
 878         jlong res = (jlong)low->get_int();
 879   #else
 880   #ifdef SPARC
 881         // For SPARC we have to swap high and low words.
 882         jlong res = jlong_from((jint)low->get_int(), (jint)value->get_int());
 883   #else
 884         jlong res = jlong_from((jint)value->get_int(), (jint)low->get_int());
 885   #endif //SPARC
 886   #endif
 887         obj->int_at_put(index, (jint)*((jint*)&res));
 888         obj->int_at_put(++index, (jint)*(((jint*)&res) + 1));
 889       } else {
 890         val = value->get_int();
 891         obj->int_at_put(index, (jint)*((jint*)&val));
 892       }
 893       break;
 894     }
 895 
 896     case T_SHORT:
 897       assert(value->type() == T_INT, "Agreement.");
 898       val = value->get_int();
 899       obj->short_at_put(index, (jshort)*((jint*)&val));
 900       break;
 901 
 902     case T_CHAR:
 903       assert(value->type() == T_INT, "Agreement.");
 904       val = value->get_int();
 905       obj->char_at_put(index, (jchar)*((jint*)&val));
 906       break;
 907 
 908     case T_BYTE:
 909       assert(value->type() == T_INT, "Agreement.");
 910       val = value->get_int();
 911       obj->byte_at_put(index, (jbyte)*((jint*)&val));
 912       break;
 913 
 914     case T_BOOLEAN:
 915       assert(value->type() == T_INT, "Agreement.");
 916       val = value->get_int();
 917       obj->bool_at_put(index, (jboolean)*((jint*)&val));
 918       break;
 919 
 920       default:
 921         ShouldNotReachHere();
 922     }
 923     index++;
 924   }
 925 }
 926 
 927 
 928 // restore fields of an eliminated object array
 929 void Deoptimization::reassign_object_array_elements(frame* fr, RegisterMap* reg_map, ObjectValue* sv, objArrayOop obj) {
 930   for (int i = 0; i < sv->field_size(); i++) {
 931     StackValue* value = StackValue::create_stack_value(fr, reg_map, sv->field_at(i));
 932     assert(value->type() == T_OBJECT, "object element expected");
 933     obj->obj_at_put(i, value->get_obj()());
 934   }
 935 }
 936 
 937 class ReassignedField {
 938 public:
 939   int _offset;
 940   BasicType _type;
 941 public:
 942   ReassignedField() {
 943     _offset = 0;
 944     _type = T_ILLEGAL;
 945   }
 946 };
 947 
 948 int compare(ReassignedField* left, ReassignedField* right) {
 949   return left->_offset - right->_offset;
 950 }
 951 
 952 // Restore fields of an eliminated instance object using the same field order
 953 // returned by HotSpotResolvedObjectTypeImpl.getInstanceFields(true)
 954 static int reassign_fields_by_klass(InstanceKlass* klass, frame* fr, RegisterMap* reg_map, ObjectValue* sv, int svIndex, oop obj, bool skip_internal) {
 955   if (klass->superklass() != NULL) {
 956     svIndex = reassign_fields_by_klass(klass->superklass(), fr, reg_map, sv, svIndex, obj, skip_internal);
 957   }
 958 
 959   GrowableArray<ReassignedField>* fields = new GrowableArray<ReassignedField>();
 960   for (AllFieldStream fs(klass); !fs.done(); fs.next()) {
 961     if (!fs.access_flags().is_static() && (!skip_internal || !fs.access_flags().is_internal())) {
 962       ReassignedField field;
 963       field._offset = fs.offset();
 964       field._type = FieldType::basic_type(fs.signature());
 965       fields->append(field);
 966     }
 967   }
 968   fields->sort(compare);
 969   for (int i = 0; i < fields->length(); i++) {
 970     intptr_t val;
 971     ScopeValue* scope_field = sv->field_at(svIndex);
 972     StackValue* value = StackValue::create_stack_value(fr, reg_map, scope_field);
 973     int offset = fields->at(i)._offset;
 974     BasicType type = fields->at(i)._type;
 975     switch (type) {
 976       case T_OBJECT: case T_ARRAY:
 977         assert(value->type() == T_OBJECT, "Agreement.");
 978         obj->obj_field_put(offset, value->get_obj()());
 979         break;
 980 
 981       // Have to cast to INT (32 bits) pointer to avoid little/big-endian problem.
 982       case T_INT: case T_FLOAT: { // 4 bytes.
 983         assert(value->type() == T_INT, "Agreement.");
 984         bool big_value = false;
 985         if (i+1 < fields->length() && fields->at(i+1)._type == T_INT) {
 986           if (scope_field->is_location()) {
 987             Location::Type type = ((LocationValue*) scope_field)->location().type();
 988             if (type == Location::dbl || type == Location::lng) {
 989               big_value = true;
 990             }
 991           }
 992           if (scope_field->is_constant_int()) {
 993             ScopeValue* next_scope_field = sv->field_at(svIndex + 1);
 994             if (next_scope_field->is_constant_long() || next_scope_field->is_constant_double()) {
 995               big_value = true;
 996             }
 997           }
 998         }
 999 
1000         if (big_value) {
1001           i++;
1002           assert(i < fields->length(), "second T_INT field needed");
1003           assert(fields->at(i)._type == T_INT, "T_INT field needed");
1004         } else {
1005           val = value->get_int();
1006           obj->int_field_put(offset, (jint)*((jint*)&val));
1007           break;
1008         }
1009       }
1010         /* no break */
1011 
1012       case T_LONG: case T_DOUBLE: {
1013         assert(value->type() == T_INT, "Agreement.");
1014         StackValue* low = StackValue::create_stack_value(fr, reg_map, sv->field_at(++svIndex));
1015 #ifdef _LP64
1016         jlong res = (jlong)low->get_int();
1017 #else
1018 #ifdef SPARC
1019         // For SPARC we have to swap high and low words.
1020         jlong res = jlong_from((jint)low->get_int(), (jint)value->get_int());
1021 #else
1022         jlong res = jlong_from((jint)value->get_int(), (jint)low->get_int());
1023 #endif //SPARC
1024 #endif
1025         obj->long_field_put(offset, res);
1026         break;
1027       }
1028 
1029       case T_SHORT:
1030         assert(value->type() == T_INT, "Agreement.");
1031         val = value->get_int();
1032         obj->short_field_put(offset, (jshort)*((jint*)&val));
1033         break;
1034 
1035       case T_CHAR:
1036         assert(value->type() == T_INT, "Agreement.");
1037         val = value->get_int();
1038         obj->char_field_put(offset, (jchar)*((jint*)&val));
1039         break;
1040 
1041       case T_BYTE:
1042         assert(value->type() == T_INT, "Agreement.");
1043         val = value->get_int();
1044         obj->byte_field_put(offset, (jbyte)*((jint*)&val));
1045         break;
1046 
1047       case T_BOOLEAN:
1048         assert(value->type() == T_INT, "Agreement.");
1049         val = value->get_int();
1050         obj->bool_field_put(offset, (jboolean)*((jint*)&val));
1051         break;
1052 
1053       default:
1054         ShouldNotReachHere();
1055     }
1056     svIndex++;
1057   }
1058   return svIndex;
1059 }
1060 
1061 // restore fields of all eliminated objects and arrays
1062 void Deoptimization::reassign_fields(frame* fr, RegisterMap* reg_map, GrowableArray<ScopeValue*>* objects, bool realloc_failures, bool skip_internal) {
1063   for (int i = 0; i < objects->length(); i++) {
1064     ObjectValue* sv = (ObjectValue*) objects->at(i);
1065     Klass* k = java_lang_Class::as_Klass(sv->klass()->as_ConstantOopReadValue()->value()());
1066     Handle obj = sv->value();
1067     assert(obj.not_null() || realloc_failures, "reallocation was missed");
1068     if (PrintDeoptimizationDetails) {
1069       tty->print_cr("reassign fields for object of type %s!", k->name()->as_C_string());
1070     }
1071     if (obj.is_null()) {
1072       continue;
1073     }
1074 
1075     if (k->is_instance_klass()) {
1076       InstanceKlass* ik = InstanceKlass::cast(k);
1077       reassign_fields_by_klass(ik, fr, reg_map, sv, 0, obj(), skip_internal);
1078     } else if (k->is_typeArray_klass()) {
1079       TypeArrayKlass* ak = TypeArrayKlass::cast(k);
1080       reassign_type_array_elements(fr, reg_map, sv, (typeArrayOop) obj(), ak->element_type());
1081     } else if (k->is_objArray_klass()) {
1082       reassign_object_array_elements(fr, reg_map, sv, (objArrayOop) obj());
1083     }
1084   }
1085 }
1086 
1087 
1088 // relock objects for which synchronization was eliminated
1089 void Deoptimization::relock_objects(GrowableArray<MonitorInfo*>* monitors, JavaThread* thread, bool realloc_failures) {
1090   for (int i = 0; i < monitors->length(); i++) {
1091     MonitorInfo* mon_info = monitors->at(i);
1092     if (mon_info->eliminated()) {
1093       assert(!mon_info->owner_is_scalar_replaced() || realloc_failures, "reallocation was missed");
1094       if (!mon_info->owner_is_scalar_replaced()) {
1095         Handle obj(thread, mon_info->owner());
1096         markOop mark = obj->mark();
1097         if (UseBiasedLocking && mark->has_bias_pattern()) {
1098           // New allocated objects may have the mark set to anonymously biased.
1099           // Also the deoptimized method may called methods with synchronization
1100           // where the thread-local object is bias locked to the current thread.
1101           assert(mark->is_biased_anonymously() ||
1102                  mark->biased_locker() == thread, "should be locked to current thread");
1103           // Reset mark word to unbiased prototype.
1104           markOop unbiased_prototype = markOopDesc::prototype()->set_age(mark->age());
1105           obj->set_mark(unbiased_prototype);
1106         }
1107         BasicLock* lock = mon_info->lock();
1108         ObjectSynchronizer::slow_enter(obj, lock, thread);
1109         assert(mon_info->owner()->is_locked(), "object must be locked now");
1110       }
1111     }
1112   }
1113 }
1114 
1115 
1116 #ifndef PRODUCT
1117 // print information about reallocated objects
1118 void Deoptimization::print_objects(GrowableArray<ScopeValue*>* objects, bool realloc_failures) {
1119   fieldDescriptor fd;
1120 
1121   for (int i = 0; i < objects->length(); i++) {
1122     ObjectValue* sv = (ObjectValue*) objects->at(i);
1123     Klass* k = java_lang_Class::as_Klass(sv->klass()->as_ConstantOopReadValue()->value()());
1124     Handle obj = sv->value();
1125 
1126     tty->print("     object <" INTPTR_FORMAT "> of type ", p2i(sv->value()()));
1127     k->print_value();
1128     assert(obj.not_null() || realloc_failures, "reallocation was missed");
1129     if (obj.is_null()) {
1130       tty->print(" allocation failed");
1131     } else {
1132       tty->print(" allocated (%d bytes)", obj->size() * HeapWordSize);
1133     }
1134     tty->cr();
1135 
1136     if (Verbose && !obj.is_null()) {
1137       k->oop_print_on(obj(), tty);
1138     }
1139   }
1140 }
1141 #endif
1142 #endif // COMPILER2_OR_JVMCI
1143 
1144 vframeArray* Deoptimization::create_vframeArray(JavaThread* thread, frame fr, RegisterMap *reg_map, GrowableArray<compiledVFrame*>* chunk, bool realloc_failures) {
1145   Events::log(thread, "DEOPT PACKING pc=" INTPTR_FORMAT " sp=" INTPTR_FORMAT, p2i(fr.pc()), p2i(fr.sp()));
1146 
1147 #ifndef PRODUCT
1148   if (PrintDeoptimizationDetails) {
1149     ttyLocker ttyl;
1150     tty->print("DEOPT PACKING thread " INTPTR_FORMAT " ", p2i(thread));
1151     fr.print_on(tty);
1152     tty->print_cr("     Virtual frames (innermost first):");
1153     for (int index = 0; index < chunk->length(); index++) {
1154       compiledVFrame* vf = chunk->at(index);
1155       tty->print("       %2d - ", index);
1156       vf->print_value();
1157       int bci = chunk->at(index)->raw_bci();
1158       const char* code_name;
1159       if (bci == SynchronizationEntryBCI) {
1160         code_name = "sync entry";
1161       } else {
1162         Bytecodes::Code code = vf->method()->code_at(bci);
1163         code_name = Bytecodes::name(code);
1164       }
1165       tty->print(" - %s", code_name);
1166       tty->print_cr(" @ bci %d ", bci);
1167       if (Verbose) {
1168         vf->print();
1169         tty->cr();
1170       }
1171     }
1172   }
1173 #endif
1174 
1175   // Register map for next frame (used for stack crawl).  We capture
1176   // the state of the deopt'ing frame's caller.  Thus if we need to
1177   // stuff a C2I adapter we can properly fill in the callee-save
1178   // register locations.
1179   frame caller = fr.sender(reg_map);
1180   int frame_size = caller.sp() - fr.sp();
1181 
1182   frame sender = caller;
1183 
1184   // Since the Java thread being deoptimized will eventually adjust it's own stack,
1185   // the vframeArray containing the unpacking information is allocated in the C heap.
1186   // For Compiler1, the caller of the deoptimized frame is saved for use by unpack_frames().
1187   vframeArray* array = vframeArray::allocate(thread, frame_size, chunk, reg_map, sender, caller, fr, realloc_failures);
1188 
1189   // Compare the vframeArray to the collected vframes
1190   assert(array->structural_compare(thread, chunk), "just checking");
1191 
1192 #ifndef PRODUCT
1193   if (PrintDeoptimizationDetails) {
1194     ttyLocker ttyl;
1195     tty->print_cr("     Created vframeArray " INTPTR_FORMAT, p2i(array));
1196   }
1197 #endif // PRODUCT
1198 
1199   return array;
1200 }
1201 
1202 #if COMPILER2_OR_JVMCI
1203 void Deoptimization::pop_frames_failed_reallocs(JavaThread* thread, vframeArray* array) {
1204   // Reallocation of some scalar replaced objects failed. Record
1205   // that we need to pop all the interpreter frames for the
1206   // deoptimized compiled frame.
1207   assert(thread->frames_to_pop_failed_realloc() == 0, "missed frames to pop?");
1208   thread->set_frames_to_pop_failed_realloc(array->frames());
1209   // Unlock all monitors here otherwise the interpreter will see a
1210   // mix of locked and unlocked monitors (because of failed
1211   // reallocations of synchronized objects) and be confused.
1212   for (int i = 0; i < array->frames(); i++) {
1213     MonitorChunk* monitors = array->element(i)->monitors();
1214     if (monitors != NULL) {
1215       for (int j = 0; j < monitors->number_of_monitors(); j++) {
1216         BasicObjectLock* src = monitors->at(j);
1217         if (src->obj() != NULL) {
1218           ObjectSynchronizer::fast_exit(src->obj(), src->lock(), thread);
1219         }
1220       }
1221       array->element(i)->free_monitors(thread);
1222 #ifdef ASSERT
1223       array->element(i)->set_removed_monitors();
1224 #endif
1225     }
1226   }
1227 }
1228 #endif
1229 
1230 static void collect_monitors(compiledVFrame* cvf, GrowableArray<Handle>* objects_to_revoke) {
1231   GrowableArray<MonitorInfo*>* monitors = cvf->monitors();
1232   Thread* thread = Thread::current();
1233   for (int i = 0; i < monitors->length(); i++) {
1234     MonitorInfo* mon_info = monitors->at(i);
1235     if (!mon_info->eliminated() && mon_info->owner() != NULL) {
1236       objects_to_revoke->append(Handle(thread, mon_info->owner()));
1237     }
1238   }
1239 }
1240 
1241 
1242 void Deoptimization::revoke_biases_of_monitors(JavaThread* thread, frame fr, RegisterMap* map) {
1243   if (!UseBiasedLocking) {
1244     return;
1245   }
1246 
1247   GrowableArray<Handle>* objects_to_revoke = new GrowableArray<Handle>();
1248 
1249   // Unfortunately we don't have a RegisterMap available in most of
1250   // the places we want to call this routine so we need to walk the
1251   // stack again to update the register map.
1252   if (map == NULL || !map->update_map()) {
1253     StackFrameStream sfs(thread, true);
1254     bool found = false;
1255     while (!found && !sfs.is_done()) {
1256       frame* cur = sfs.current();
1257       sfs.next();
1258       found = cur->id() == fr.id();
1259     }
1260     assert(found, "frame to be deoptimized not found on target thread's stack");
1261     map = sfs.register_map();
1262   }
1263 
1264   vframe* vf = vframe::new_vframe(&fr, map, thread);
1265   compiledVFrame* cvf = compiledVFrame::cast(vf);
1266   // Revoke monitors' biases in all scopes
1267   while (!cvf->is_top()) {
1268     collect_monitors(cvf, objects_to_revoke);
1269     cvf = compiledVFrame::cast(cvf->sender());
1270   }
1271   collect_monitors(cvf, objects_to_revoke);
1272 
1273   if (SafepointSynchronize::is_at_safepoint()) {
1274     BiasedLocking::revoke_at_safepoint(objects_to_revoke);
1275   } else {
1276     BiasedLocking::revoke(objects_to_revoke);
1277   }
1278 }
1279 
1280 
1281 void Deoptimization::revoke_biases_of_monitors(CodeBlob* cb) {
1282   if (!UseBiasedLocking) {
1283     return;
1284   }
1285 
1286   assert(SafepointSynchronize::is_at_safepoint(), "must only be called from safepoint");
1287   GrowableArray<Handle>* objects_to_revoke = new GrowableArray<Handle>();
1288   for (JavaThreadIteratorWithHandle jtiwh; JavaThread *jt = jtiwh.next(); ) {
1289     if (jt->has_last_Java_frame()) {
1290       StackFrameStream sfs(jt, true);
1291       while (!sfs.is_done()) {
1292         frame* cur = sfs.current();
1293         if (cb->contains(cur->pc())) {
1294           vframe* vf = vframe::new_vframe(cur, sfs.register_map(), jt);
1295           compiledVFrame* cvf = compiledVFrame::cast(vf);
1296           // Revoke monitors' biases in all scopes
1297           while (!cvf->is_top()) {
1298             collect_monitors(cvf, objects_to_revoke);
1299             cvf = compiledVFrame::cast(cvf->sender());
1300           }
1301           collect_monitors(cvf, objects_to_revoke);
1302         }
1303         sfs.next();
1304       }
1305     }
1306   }
1307   BiasedLocking::revoke_at_safepoint(objects_to_revoke);
1308 }
1309 
1310 
1311 void Deoptimization::deoptimize_single_frame(JavaThread* thread, frame fr, Deoptimization::DeoptReason reason) {
1312   assert(fr.can_be_deoptimized(), "checking frame type");
1313 
1314   gather_statistics(reason, Action_none, Bytecodes::_illegal);
1315 
1316   if (LogCompilation && xtty != NULL) {
1317     CompiledMethod* cm = fr.cb()->as_compiled_method_or_null();
1318     assert(cm != NULL, "only compiled methods can deopt");
1319 
1320     ttyLocker ttyl;
1321     xtty->begin_head("deoptimized thread='" UINTX_FORMAT "' reason='%s' pc='" INTPTR_FORMAT "'",(uintx)thread->osthread()->thread_id(), trap_reason_name(reason), p2i(fr.pc()));
1322     cm->log_identity(xtty);
1323     xtty->end_head();
1324     for (ScopeDesc* sd = cm->scope_desc_at(fr.pc()); ; sd = sd->sender()) {
1325       xtty->begin_elem("jvms bci='%d'", sd->bci());
1326       xtty->method(sd->method());
1327       xtty->end_elem();
1328       if (sd->is_top())  break;
1329     }
1330     xtty->tail("deoptimized");
1331   }
1332 
1333   // Patch the compiled method so that when execution returns to it we will
1334   // deopt the execution state and return to the interpreter.
1335   fr.deoptimize(thread);
1336 }
1337 
1338 void Deoptimization::deoptimize(JavaThread* thread, frame fr, RegisterMap *map) {
1339   deoptimize(thread, fr, map, Reason_constraint);
1340 }
1341 
1342 void Deoptimization::deoptimize(JavaThread* thread, frame fr, RegisterMap *map, DeoptReason reason) {
1343   // Deoptimize only if the frame comes from compile code.
1344   // Do not deoptimize the frame which is already patched
1345   // during the execution of the loops below.
1346   if (!fr.is_compiled_frame() || fr.is_deoptimized_frame()) {
1347     return;
1348   }
1349   ResourceMark rm;
1350   DeoptimizationMarker dm;
1351   if (UseBiasedLocking) {
1352     revoke_biases_of_monitors(thread, fr, map);
1353   }
1354   deoptimize_single_frame(thread, fr, reason);
1355 
1356 }
1357 
1358 #if INCLUDE_JVMCI
1359 address Deoptimization::deoptimize_for_missing_exception_handler(CompiledMethod* cm) {
1360   // there is no exception handler for this pc => deoptimize
1361   cm->make_not_entrant();
1362 
1363   // Use Deoptimization::deoptimize for all of its side-effects:
1364   // revoking biases of monitors, gathering traps statistics, logging...
1365   // it also patches the return pc but we do not care about that
1366   // since we return a continuation to the deopt_blob below.
1367   JavaThread* thread = JavaThread::current();
1368   RegisterMap reg_map(thread, UseBiasedLocking);
1369   frame runtime_frame = thread->last_frame();
1370   frame caller_frame = runtime_frame.sender(&reg_map);
1371   assert(caller_frame.cb()->as_compiled_method_or_null() == cm, "expect top frame compiled method");
1372   Deoptimization::deoptimize(thread, caller_frame, &reg_map, Deoptimization::Reason_not_compiled_exception_handler);
1373 
1374   MethodData* trap_mdo = get_method_data(thread, cm->method(), true);
1375   if (trap_mdo != NULL) {
1376     trap_mdo->inc_trap_count(Deoptimization::Reason_not_compiled_exception_handler);
1377   }
1378 
1379   return SharedRuntime::deopt_blob()->unpack_with_exception_in_tls();
1380 }
1381 #endif
1382 
1383 void Deoptimization::deoptimize_frame_internal(JavaThread* thread, intptr_t* id, DeoptReason reason) {
1384   assert(thread == Thread::current() || SafepointSynchronize::is_at_safepoint(),
1385          "can only deoptimize other thread at a safepoint");
1386   // Compute frame and register map based on thread and sp.
1387   RegisterMap reg_map(thread, UseBiasedLocking);
1388   frame fr = thread->last_frame();
1389   while (fr.id() != id) {
1390     fr = fr.sender(&reg_map);
1391   }
1392   deoptimize(thread, fr, &reg_map, reason);
1393 }
1394 
1395 
1396 void Deoptimization::deoptimize_frame(JavaThread* thread, intptr_t* id, DeoptReason reason) {
1397   if (thread == Thread::current()) {
1398     Deoptimization::deoptimize_frame_internal(thread, id, reason);
1399   } else {
1400     VM_DeoptimizeFrame deopt(thread, id, reason);
1401     VMThread::execute(&deopt);
1402   }
1403 }
1404 
1405 void Deoptimization::deoptimize_frame(JavaThread* thread, intptr_t* id) {
1406   deoptimize_frame(thread, id, Reason_constraint);
1407 }
1408 
1409 // JVMTI PopFrame support
1410 JRT_LEAF(void, Deoptimization::popframe_preserve_args(JavaThread* thread, int bytes_to_save, void* start_address))
1411 {
1412   thread->popframe_preserve_args(in_ByteSize(bytes_to_save), start_address);
1413 }
1414 JRT_END
1415 
1416 MethodData*
1417 Deoptimization::get_method_data(JavaThread* thread, const methodHandle& m,
1418                                 bool create_if_missing) {
1419   Thread* THREAD = thread;
1420   MethodData* mdo = m()->method_data();
1421   if (mdo == NULL && create_if_missing && !HAS_PENDING_EXCEPTION) {
1422     // Build an MDO.  Ignore errors like OutOfMemory;
1423     // that simply means we won't have an MDO to update.
1424     Method::build_interpreter_method_data(m, THREAD);
1425     if (HAS_PENDING_EXCEPTION) {
1426       assert((PENDING_EXCEPTION->is_a(SystemDictionary::OutOfMemoryError_klass())), "we expect only an OOM error here");
1427       CLEAR_PENDING_EXCEPTION;
1428     }
1429     mdo = m()->method_data();
1430   }
1431   return mdo;
1432 }
1433 
1434 #if COMPILER2_OR_JVMCI
1435 void Deoptimization::load_class_by_index(const constantPoolHandle& constant_pool, int index, TRAPS) {
1436   // in case of an unresolved klass entry, load the class.
1437   if (constant_pool->tag_at(index).is_unresolved_klass()) {
1438     Klass* tk = constant_pool->klass_at_ignore_error(index, CHECK);
1439     return;
1440   }
1441 
1442   if (!constant_pool->tag_at(index).is_symbol()) return;
1443 
1444   Handle class_loader (THREAD, constant_pool->pool_holder()->class_loader());
1445   Symbol*  symbol  = constant_pool->symbol_at(index);
1446 
1447   // class name?
1448   if (symbol->byte_at(0) != '(') {
1449     Handle protection_domain (THREAD, constant_pool->pool_holder()->protection_domain());
1450     SystemDictionary::resolve_or_null(symbol, class_loader, protection_domain, CHECK);
1451     return;
1452   }
1453 
1454   // then it must be a signature!
1455   ResourceMark rm(THREAD);
1456   for (SignatureStream ss(symbol); !ss.is_done(); ss.next()) {
1457     if (ss.is_object()) {
1458       Symbol* class_name = ss.as_symbol(CHECK);
1459       Handle protection_domain (THREAD, constant_pool->pool_holder()->protection_domain());
1460       SystemDictionary::resolve_or_null(class_name, class_loader, protection_domain, CHECK);
1461     }
1462   }
1463 }
1464 
1465 
1466 void Deoptimization::load_class_by_index(const constantPoolHandle& constant_pool, int index) {
1467   EXCEPTION_MARK;
1468   load_class_by_index(constant_pool, index, THREAD);
1469   if (HAS_PENDING_EXCEPTION) {
1470     // Exception happened during classloading. We ignore the exception here, since it
1471     // is going to be rethrown since the current activation is going to be deoptimized and
1472     // the interpreter will re-execute the bytecode.
1473     CLEAR_PENDING_EXCEPTION;
1474     // Class loading called java code which may have caused a stack
1475     // overflow. If the exception was thrown right before the return
1476     // to the runtime the stack is no longer guarded. Reguard the
1477     // stack otherwise if we return to the uncommon trap blob and the
1478     // stack bang causes a stack overflow we crash.
1479     assert(THREAD->is_Java_thread(), "only a java thread can be here");
1480     JavaThread* thread = (JavaThread*)THREAD;
1481     bool guard_pages_enabled = thread->stack_guards_enabled();
1482     if (!guard_pages_enabled) guard_pages_enabled = thread->reguard_stack();
1483     assert(guard_pages_enabled, "stack banging in uncommon trap blob may cause crash");
1484   }
1485 }
1486 
1487 JRT_ENTRY(void, Deoptimization::uncommon_trap_inner(JavaThread* thread, jint trap_request)) {
1488   HandleMark hm;
1489 
1490   // uncommon_trap() is called at the beginning of the uncommon trap
1491   // handler. Note this fact before we start generating temporary frames
1492   // that can confuse an asynchronous stack walker. This counter is
1493   // decremented at the end of unpack_frames().
1494   thread->inc_in_deopt_handler();
1495 
1496   // We need to update the map if we have biased locking.
1497 #if INCLUDE_JVMCI
1498   // JVMCI might need to get an exception from the stack, which in turn requires the register map to be valid
1499   RegisterMap reg_map(thread, true);
1500 #else
1501   RegisterMap reg_map(thread, UseBiasedLocking);
1502 #endif
1503   frame stub_frame = thread->last_frame();
1504   frame fr = stub_frame.sender(&reg_map);
1505   // Make sure the calling nmethod is not getting deoptimized and removed
1506   // before we are done with it.
1507   nmethodLocker nl(fr.pc());
1508 
1509   // Log a message
1510   Events::log(thread, "Uncommon trap: trap_request=" PTR32_FORMAT " fr.pc=" INTPTR_FORMAT " relative=" INTPTR_FORMAT,
1511               trap_request, p2i(fr.pc()), fr.pc() - fr.cb()->code_begin());
1512 
1513   {
1514     ResourceMark rm;
1515 
1516     // Revoke biases of any monitors in the frame to ensure we can migrate them
1517     revoke_biases_of_monitors(thread, fr, &reg_map);
1518 
1519     DeoptReason reason = trap_request_reason(trap_request);
1520     DeoptAction action = trap_request_action(trap_request);
1521 #if INCLUDE_JVMCI
1522     int debug_id = trap_request_debug_id(trap_request);
1523 #endif
1524     jint unloaded_class_index = trap_request_index(trap_request); // CP idx or -1
1525 
1526     vframe*  vf  = vframe::new_vframe(&fr, &reg_map, thread);
1527     compiledVFrame* cvf = compiledVFrame::cast(vf);
1528 
1529     CompiledMethod* nm = cvf->code();
1530 
1531     ScopeDesc*      trap_scope  = cvf->scope();
1532 
1533     if (TraceDeoptimization) {
1534       ttyLocker ttyl;
1535       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()
1536 #if INCLUDE_JVMCI
1537           , debug_id
1538 #endif
1539           );
1540     }
1541 
1542     methodHandle    trap_method = trap_scope->method();
1543     int             trap_bci    = trap_scope->bci();
1544 #if INCLUDE_JVMCI
1545     oop speculation = thread->pending_failed_speculation();
1546     if (nm->is_compiled_by_jvmci()) {
1547       if (speculation != NULL) {
1548         oop speculation_log = nm->as_nmethod()->speculation_log();
1549         if (speculation_log != NULL) {
1550           if (TraceDeoptimization || TraceUncollectedSpeculations) {
1551             if (HotSpotSpeculationLog::lastFailed(speculation_log) != NULL) {
1552               tty->print_cr("A speculation that was not collected by the compiler is being overwritten");
1553             }
1554           }
1555           if (TraceDeoptimization) {
1556             tty->print_cr("Saving speculation to speculation log");
1557           }
1558           HotSpotSpeculationLog::set_lastFailed(speculation_log, speculation);
1559         } else {
1560           if (TraceDeoptimization) {
1561             tty->print_cr("Speculation present but no speculation log");
1562           }
1563         }
1564         thread->set_pending_failed_speculation(NULL);
1565       } else {
1566         if (TraceDeoptimization) {
1567           tty->print_cr("No speculation");
1568         }
1569       }
1570     } else {
1571       assert(speculation == NULL, "There should not be a speculation for method compiled by non-JVMCI compilers");
1572     }
1573 
1574     if (trap_bci == SynchronizationEntryBCI) {
1575       trap_bci = 0;
1576       thread->set_pending_monitorenter(true);
1577     }
1578 
1579     if (reason == Deoptimization::Reason_transfer_to_interpreter) {
1580       thread->set_pending_transfer_to_interpreter(true);
1581     }
1582 #endif
1583 
1584     Bytecodes::Code trap_bc     = trap_method->java_code_at(trap_bci);
1585     // Record this event in the histogram.
1586     gather_statistics(reason, action, trap_bc);
1587 
1588     // Ensure that we can record deopt. history:
1589     // Need MDO to record RTM code generation state.
1590     bool create_if_missing = ProfileTraps || UseCodeAging RTM_OPT_ONLY( || UseRTMLocking );
1591 
1592     methodHandle profiled_method;
1593 #if INCLUDE_JVMCI
1594     if (nm->is_compiled_by_jvmci()) {
1595       profiled_method = nm->method();
1596     } else {
1597       profiled_method = trap_method;
1598     }
1599 #else
1600     profiled_method = trap_method;
1601 #endif
1602 
1603     MethodData* trap_mdo =
1604       get_method_data(thread, profiled_method, create_if_missing);
1605 
1606     // Log a message
1607     Events::log_deopt_message(thread, "Uncommon trap: reason=%s action=%s pc=" INTPTR_FORMAT " method=%s @ %d %s",
1608                               trap_reason_name(reason), trap_action_name(action), p2i(fr.pc()),
1609                               trap_method->name_and_sig_as_C_string(), trap_bci, nm->compiler_name());
1610 
1611     // Print a bunch of diagnostics, if requested.
1612     if (TraceDeoptimization || LogCompilation) {
1613       ResourceMark rm;
1614       ttyLocker ttyl;
1615       char buf[100];
1616       if (xtty != NULL) {
1617         xtty->begin_head("uncommon_trap thread='" UINTX_FORMAT "' %s",
1618                          os::current_thread_id(),
1619                          format_trap_request(buf, sizeof(buf), trap_request));
1620         nm->log_identity(xtty);
1621       }
1622       Symbol* class_name = NULL;
1623       bool unresolved = false;
1624       if (unloaded_class_index >= 0) {
1625         constantPoolHandle constants (THREAD, trap_method->constants());
1626         if (constants->tag_at(unloaded_class_index).is_unresolved_klass()) {
1627           class_name = constants->klass_name_at(unloaded_class_index);
1628           unresolved = true;
1629           if (xtty != NULL)
1630             xtty->print(" unresolved='1'");
1631         } else if (constants->tag_at(unloaded_class_index).is_symbol()) {
1632           class_name = constants->symbol_at(unloaded_class_index);
1633         }
1634         if (xtty != NULL)
1635           xtty->name(class_name);
1636       }
1637       if (xtty != NULL && trap_mdo != NULL && (int)reason < (int)MethodData::_trap_hist_limit) {
1638         // Dump the relevant MDO state.
1639         // This is the deopt count for the current reason, any previous
1640         // reasons or recompiles seen at this point.
1641         int dcnt = trap_mdo->trap_count(reason);
1642         if (dcnt != 0)
1643           xtty->print(" count='%d'", dcnt);
1644         ProfileData* pdata = trap_mdo->bci_to_data(trap_bci);
1645         int dos = (pdata == NULL)? 0: pdata->trap_state();
1646         if (dos != 0) {
1647           xtty->print(" state='%s'", format_trap_state(buf, sizeof(buf), dos));
1648           if (trap_state_is_recompiled(dos)) {
1649             int recnt2 = trap_mdo->overflow_recompile_count();
1650             if (recnt2 != 0)
1651               xtty->print(" recompiles2='%d'", recnt2);
1652           }
1653         }
1654       }
1655       if (xtty != NULL) {
1656         xtty->stamp();
1657         xtty->end_head();
1658       }
1659       if (TraceDeoptimization) {  // make noise on the tty
1660         tty->print("Uncommon trap occurred in");
1661         nm->method()->print_short_name(tty);
1662         tty->print(" compiler=%s compile_id=%d", nm->compiler_name(), nm->compile_id());
1663 #if INCLUDE_JVMCI
1664         if (nm->is_nmethod()) {
1665           char* installed_code_name = nm->as_nmethod()->jvmci_installed_code_name(buf, sizeof(buf));
1666           if (installed_code_name != NULL) {
1667             tty->print(" (JVMCI: installed code name=%s) ", installed_code_name);
1668           }
1669         }
1670 #endif
1671         tty->print(" (@" INTPTR_FORMAT ") thread=" UINTX_FORMAT " reason=%s action=%s unloaded_class_index=%d" JVMCI_ONLY(" debug_id=%d"),
1672                    p2i(fr.pc()),
1673                    os::current_thread_id(),
1674                    trap_reason_name(reason),
1675                    trap_action_name(action),
1676                    unloaded_class_index
1677 #if INCLUDE_JVMCI
1678                    , debug_id
1679 #endif
1680                    );
1681         if (class_name != NULL) {
1682           tty->print(unresolved ? " unresolved class: " : " symbol: ");
1683           class_name->print_symbol_on(tty);
1684         }
1685         tty->cr();
1686       }
1687       if (xtty != NULL) {
1688         // Log the precise location of the trap.
1689         for (ScopeDesc* sd = trap_scope; ; sd = sd->sender()) {
1690           xtty->begin_elem("jvms bci='%d'", sd->bci());
1691           xtty->method(sd->method());
1692           xtty->end_elem();
1693           if (sd->is_top())  break;
1694         }
1695         xtty->tail("uncommon_trap");
1696       }
1697     }
1698     // (End diagnostic printout.)
1699 
1700     // Load class if necessary
1701     if (unloaded_class_index >= 0) {
1702       constantPoolHandle constants(THREAD, trap_method->constants());
1703       load_class_by_index(constants, unloaded_class_index);
1704     }
1705 
1706     // Flush the nmethod if necessary and desirable.
1707     //
1708     // We need to avoid situations where we are re-flushing the nmethod
1709     // because of a hot deoptimization site.  Repeated flushes at the same
1710     // point need to be detected by the compiler and avoided.  If the compiler
1711     // cannot avoid them (or has a bug and "refuses" to avoid them), this
1712     // module must take measures to avoid an infinite cycle of recompilation
1713     // and deoptimization.  There are several such measures:
1714     //
1715     //   1. If a recompilation is ordered a second time at some site X
1716     //   and for the same reason R, the action is adjusted to 'reinterpret',
1717     //   to give the interpreter time to exercise the method more thoroughly.
1718     //   If this happens, the method's overflow_recompile_count is incremented.
1719     //
1720     //   2. If the compiler fails to reduce the deoptimization rate, then
1721     //   the method's overflow_recompile_count will begin to exceed the set
1722     //   limit PerBytecodeRecompilationCutoff.  If this happens, the action
1723     //   is adjusted to 'make_not_compilable', and the method is abandoned
1724     //   to the interpreter.  This is a performance hit for hot methods,
1725     //   but is better than a disastrous infinite cycle of recompilations.
1726     //   (Actually, only the method containing the site X is abandoned.)
1727     //
1728     //   3. In parallel with the previous measures, if the total number of
1729     //   recompilations of a method exceeds the much larger set limit
1730     //   PerMethodRecompilationCutoff, the method is abandoned.
1731     //   This should only happen if the method is very large and has
1732     //   many "lukewarm" deoptimizations.  The code which enforces this
1733     //   limit is elsewhere (class nmethod, class Method).
1734     //
1735     // Note that the per-BCI 'is_recompiled' bit gives the compiler one chance
1736     // to recompile at each bytecode independently of the per-BCI cutoff.
1737     //
1738     // The decision to update code is up to the compiler, and is encoded
1739     // in the Action_xxx code.  If the compiler requests Action_none
1740     // no trap state is changed, no compiled code is changed, and the
1741     // computation suffers along in the interpreter.
1742     //
1743     // The other action codes specify various tactics for decompilation
1744     // and recompilation.  Action_maybe_recompile is the loosest, and
1745     // allows the compiled code to stay around until enough traps are seen,
1746     // and until the compiler gets around to recompiling the trapping method.
1747     //
1748     // The other actions cause immediate removal of the present code.
1749 
1750     // Traps caused by injected profile shouldn't pollute trap counts.
1751     bool injected_profile_trap = trap_method->has_injected_profile() &&
1752                                  (reason == Reason_intrinsic || reason == Reason_unreached);
1753 
1754     bool update_trap_state = (reason != Reason_tenured) && !injected_profile_trap;
1755     bool make_not_entrant = false;
1756     bool make_not_compilable = false;
1757     bool reprofile = false;
1758     switch (action) {
1759     case Action_none:
1760       // Keep the old code.
1761       update_trap_state = false;
1762       break;
1763     case Action_maybe_recompile:
1764       // Do not need to invalidate the present code, but we can
1765       // initiate another
1766       // Start compiler without (necessarily) invalidating the nmethod.
1767       // The system will tolerate the old code, but new code should be
1768       // generated when possible.
1769       break;
1770     case Action_reinterpret:
1771       // Go back into the interpreter for a while, and then consider
1772       // recompiling form scratch.
1773       make_not_entrant = true;
1774       // Reset invocation counter for outer most method.
1775       // This will allow the interpreter to exercise the bytecodes
1776       // for a while before recompiling.
1777       // By contrast, Action_make_not_entrant is immediate.
1778       //
1779       // Note that the compiler will track null_check, null_assert,
1780       // range_check, and class_check events and log them as if they
1781       // had been traps taken from compiled code.  This will update
1782       // the MDO trap history so that the next compilation will
1783       // properly detect hot trap sites.
1784       reprofile = true;
1785       break;
1786     case Action_make_not_entrant:
1787       // Request immediate recompilation, and get rid of the old code.
1788       // Make them not entrant, so next time they are called they get
1789       // recompiled.  Unloaded classes are loaded now so recompile before next
1790       // time they are called.  Same for uninitialized.  The interpreter will
1791       // link the missing class, if any.
1792       make_not_entrant = true;
1793       break;
1794     case Action_make_not_compilable:
1795       // Give up on compiling this method at all.
1796       make_not_entrant = true;
1797       make_not_compilable = true;
1798       break;
1799     default:
1800       ShouldNotReachHere();
1801     }
1802 
1803     // Setting +ProfileTraps fixes the following, on all platforms:
1804     // 4852688: ProfileInterpreter is off by default for ia64.  The result is
1805     // infinite heroic-opt-uncommon-trap/deopt/recompile cycles, since the
1806     // recompile relies on a MethodData* to record heroic opt failures.
1807 
1808     // Whether the interpreter is producing MDO data or not, we also need
1809     // to use the MDO to detect hot deoptimization points and control
1810     // aggressive optimization.
1811     bool inc_recompile_count = false;
1812     ProfileData* pdata = NULL;
1813     if (ProfileTraps && !is_client_compilation_mode_vm() && update_trap_state && trap_mdo != NULL) {
1814       assert(trap_mdo == get_method_data(thread, profiled_method, false), "sanity");
1815       uint this_trap_count = 0;
1816       bool maybe_prior_trap = false;
1817       bool maybe_prior_recompile = false;
1818       pdata = query_update_method_data(trap_mdo, trap_bci, reason, true,
1819 #if INCLUDE_JVMCI
1820                                    nm->is_compiled_by_jvmci() && nm->is_osr_method(),
1821 #endif
1822                                    nm->method(),
1823                                    //outputs:
1824                                    this_trap_count,
1825                                    maybe_prior_trap,
1826                                    maybe_prior_recompile);
1827       // Because the interpreter also counts null, div0, range, and class
1828       // checks, these traps from compiled code are double-counted.
1829       // This is harmless; it just means that the PerXTrapLimit values
1830       // are in effect a little smaller than they look.
1831 
1832       DeoptReason per_bc_reason = reason_recorded_per_bytecode_if_any(reason);
1833       if (per_bc_reason != Reason_none) {
1834         // Now take action based on the partially known per-BCI history.
1835         if (maybe_prior_trap
1836             && this_trap_count >= (uint)PerBytecodeTrapLimit) {
1837           // If there are too many traps at this BCI, force a recompile.
1838           // This will allow the compiler to see the limit overflow, and
1839           // take corrective action, if possible.  The compiler generally
1840           // does not use the exact PerBytecodeTrapLimit value, but instead
1841           // changes its tactics if it sees any traps at all.  This provides
1842           // a little hysteresis, delaying a recompile until a trap happens
1843           // several times.
1844           //
1845           // Actually, since there is only one bit of counter per BCI,
1846           // the possible per-BCI counts are {0,1,(per-method count)}.
1847           // This produces accurate results if in fact there is only
1848           // one hot trap site, but begins to get fuzzy if there are
1849           // many sites.  For example, if there are ten sites each
1850           // trapping two or more times, they each get the blame for
1851           // all of their traps.
1852           make_not_entrant = true;
1853         }
1854 
1855         // Detect repeated recompilation at the same BCI, and enforce a limit.
1856         if (make_not_entrant && maybe_prior_recompile) {
1857           // More than one recompile at this point.
1858           inc_recompile_count = maybe_prior_trap;
1859         }
1860       } else {
1861         // For reasons which are not recorded per-bytecode, we simply
1862         // force recompiles unconditionally.
1863         // (Note that PerMethodRecompilationCutoff is enforced elsewhere.)
1864         make_not_entrant = true;
1865       }
1866 
1867       // Go back to the compiler if there are too many traps in this method.
1868       if (this_trap_count >= per_method_trap_limit(reason)) {
1869         // If there are too many traps in this method, force a recompile.
1870         // This will allow the compiler to see the limit overflow, and
1871         // take corrective action, if possible.
1872         // (This condition is an unlikely backstop only, because the
1873         // PerBytecodeTrapLimit is more likely to take effect first,
1874         // if it is applicable.)
1875         make_not_entrant = true;
1876       }
1877 
1878       // Here's more hysteresis:  If there has been a recompile at
1879       // this trap point already, run the method in the interpreter
1880       // for a while to exercise it more thoroughly.
1881       if (make_not_entrant && maybe_prior_recompile && maybe_prior_trap) {
1882         reprofile = true;
1883       }
1884     }
1885 
1886     // Take requested actions on the method:
1887 
1888     // Recompile
1889     if (make_not_entrant) {
1890       if (!nm->make_not_entrant()) {
1891         return; // the call did not change nmethod's state
1892       }
1893 
1894       if (pdata != NULL) {
1895         // Record the recompilation event, if any.
1896         int tstate0 = pdata->trap_state();
1897         int tstate1 = trap_state_set_recompiled(tstate0, true);
1898         if (tstate1 != tstate0)
1899           pdata->set_trap_state(tstate1);
1900       }
1901 
1902 #if INCLUDE_RTM_OPT
1903       // Restart collecting RTM locking abort statistic if the method
1904       // is recompiled for a reason other than RTM state change.
1905       // Assume that in new recompiled code the statistic could be different,
1906       // for example, due to different inlining.
1907       if ((reason != Reason_rtm_state_change) && (trap_mdo != NULL) &&
1908           UseRTMDeopt && (nm->as_nmethod()->rtm_state() != ProfileRTM)) {
1909         trap_mdo->atomic_set_rtm_state(ProfileRTM);
1910       }
1911 #endif
1912       // For code aging we count traps separately here, using make_not_entrant()
1913       // as a guard against simultaneous deopts in multiple threads.
1914       if (reason == Reason_tenured && trap_mdo != NULL) {
1915         trap_mdo->inc_tenure_traps();
1916       }
1917     }
1918 
1919     if (inc_recompile_count) {
1920       trap_mdo->inc_overflow_recompile_count();
1921       if ((uint)trap_mdo->overflow_recompile_count() >
1922           (uint)PerBytecodeRecompilationCutoff) {
1923         // Give up on the method containing the bad BCI.
1924         if (trap_method() == nm->method()) {
1925           make_not_compilable = true;
1926         } else {
1927           trap_method->set_not_compilable(CompLevel_full_optimization, true, "overflow_recompile_count > PerBytecodeRecompilationCutoff");
1928           // But give grace to the enclosing nm->method().
1929         }
1930       }
1931     }
1932 
1933     // Reprofile
1934     if (reprofile) {
1935       CompilationPolicy::policy()->reprofile(trap_scope, nm->is_osr_method());
1936     }
1937 
1938     // Give up compiling
1939     if (make_not_compilable && !nm->method()->is_not_compilable(CompLevel_full_optimization)) {
1940       assert(make_not_entrant, "consistent");
1941       nm->method()->set_not_compilable(CompLevel_full_optimization);
1942     }
1943 
1944   } // Free marked resources
1945 
1946 }
1947 JRT_END
1948 
1949 ProfileData*
1950 Deoptimization::query_update_method_data(MethodData* trap_mdo,
1951                                          int trap_bci,
1952                                          Deoptimization::DeoptReason reason,
1953                                          bool update_total_trap_count,
1954 #if INCLUDE_JVMCI
1955                                          bool is_osr,
1956 #endif
1957                                          Method* compiled_method,
1958                                          //outputs:
1959                                          uint& ret_this_trap_count,
1960                                          bool& ret_maybe_prior_trap,
1961                                          bool& ret_maybe_prior_recompile) {
1962   bool maybe_prior_trap = false;
1963   bool maybe_prior_recompile = false;
1964   uint this_trap_count = 0;
1965   if (update_total_trap_count) {
1966     uint idx = reason;
1967 #if INCLUDE_JVMCI
1968     if (is_osr) {
1969       idx += Reason_LIMIT;
1970     }
1971 #endif
1972     uint prior_trap_count = trap_mdo->trap_count(idx);
1973     this_trap_count  = trap_mdo->inc_trap_count(idx);
1974 
1975     // If the runtime cannot find a place to store trap history,
1976     // it is estimated based on the general condition of the method.
1977     // If the method has ever been recompiled, or has ever incurred
1978     // a trap with the present reason , then this BCI is assumed
1979     // (pessimistically) to be the culprit.
1980     maybe_prior_trap      = (prior_trap_count != 0);
1981     maybe_prior_recompile = (trap_mdo->decompile_count() != 0);
1982   }
1983   ProfileData* pdata = NULL;
1984 
1985 
1986   // For reasons which are recorded per bytecode, we check per-BCI data.
1987   DeoptReason per_bc_reason = reason_recorded_per_bytecode_if_any(reason);
1988   assert(per_bc_reason != Reason_none || update_total_trap_count, "must be");
1989   if (per_bc_reason != Reason_none) {
1990     // Find the profile data for this BCI.  If there isn't one,
1991     // try to allocate one from the MDO's set of spares.
1992     // This will let us detect a repeated trap at this point.
1993     pdata = trap_mdo->allocate_bci_to_data(trap_bci, reason_is_speculate(reason) ? compiled_method : NULL);
1994 
1995     if (pdata != NULL) {
1996       if (reason_is_speculate(reason) && !pdata->is_SpeculativeTrapData()) {
1997         if (LogCompilation && xtty != NULL) {
1998           ttyLocker ttyl;
1999           // no more room for speculative traps in this MDO
2000           xtty->elem("speculative_traps_oom");
2001         }
2002       }
2003       // Query the trap state of this profile datum.
2004       int tstate0 = pdata->trap_state();
2005       if (!trap_state_has_reason(tstate0, per_bc_reason))
2006         maybe_prior_trap = false;
2007       if (!trap_state_is_recompiled(tstate0))
2008         maybe_prior_recompile = false;
2009 
2010       // Update the trap state of this profile datum.
2011       int tstate1 = tstate0;
2012       // Record the reason.
2013       tstate1 = trap_state_add_reason(tstate1, per_bc_reason);
2014       // Store the updated state on the MDO, for next time.
2015       if (tstate1 != tstate0)
2016         pdata->set_trap_state(tstate1);
2017     } else {
2018       if (LogCompilation && xtty != NULL) {
2019         ttyLocker ttyl;
2020         // Missing MDP?  Leave a small complaint in the log.
2021         xtty->elem("missing_mdp bci='%d'", trap_bci);
2022       }
2023     }
2024   }
2025 
2026   // Return results:
2027   ret_this_trap_count = this_trap_count;
2028   ret_maybe_prior_trap = maybe_prior_trap;
2029   ret_maybe_prior_recompile = maybe_prior_recompile;
2030   return pdata;
2031 }
2032 
2033 void
2034 Deoptimization::update_method_data_from_interpreter(MethodData* trap_mdo, int trap_bci, int reason) {
2035   ResourceMark rm;
2036   // Ignored outputs:
2037   uint ignore_this_trap_count;
2038   bool ignore_maybe_prior_trap;
2039   bool ignore_maybe_prior_recompile;
2040   assert(!reason_is_speculate(reason), "reason speculate only used by compiler");
2041   // JVMCI uses the total counts to determine if deoptimizations are happening too frequently -> do not adjust total counts
2042   bool update_total_counts = JVMCI_ONLY(false) NOT_JVMCI(true);
2043   query_update_method_data(trap_mdo, trap_bci,
2044                            (DeoptReason)reason,
2045                            update_total_counts,
2046 #if INCLUDE_JVMCI
2047                            false,
2048 #endif
2049                            NULL,
2050                            ignore_this_trap_count,
2051                            ignore_maybe_prior_trap,
2052                            ignore_maybe_prior_recompile);
2053 }
2054 
2055 Deoptimization::UnrollBlock* Deoptimization::uncommon_trap(JavaThread* thread, jint trap_request, jint exec_mode) {
2056   if (TraceDeoptimization) {
2057     tty->print("Uncommon trap ");
2058   }
2059   // Still in Java no safepoints
2060   {
2061     // This enters VM and may safepoint
2062     uncommon_trap_inner(thread, trap_request);
2063   }
2064   return fetch_unroll_info_helper(thread, exec_mode);
2065 }
2066 
2067 // Local derived constants.
2068 // Further breakdown of DataLayout::trap_state, as promised by DataLayout.
2069 const int DS_REASON_MASK   = DataLayout::trap_mask >> 1;
2070 const int DS_RECOMPILE_BIT = DataLayout::trap_mask - DS_REASON_MASK;
2071 
2072 //---------------------------trap_state_reason---------------------------------
2073 Deoptimization::DeoptReason
2074 Deoptimization::trap_state_reason(int trap_state) {
2075   // This assert provides the link between the width of DataLayout::trap_bits
2076   // and the encoding of "recorded" reasons.  It ensures there are enough
2077   // bits to store all needed reasons in the per-BCI MDO profile.
2078   assert(DS_REASON_MASK >= Reason_RECORDED_LIMIT, "enough bits");
2079   int recompile_bit = (trap_state & DS_RECOMPILE_BIT);
2080   trap_state -= recompile_bit;
2081   if (trap_state == DS_REASON_MASK) {
2082     return Reason_many;
2083   } else {
2084     assert((int)Reason_none == 0, "state=0 => Reason_none");
2085     return (DeoptReason)trap_state;
2086   }
2087 }
2088 //-------------------------trap_state_has_reason-------------------------------
2089 int Deoptimization::trap_state_has_reason(int trap_state, int reason) {
2090   assert(reason_is_recorded_per_bytecode((DeoptReason)reason), "valid reason");
2091   assert(DS_REASON_MASK >= Reason_RECORDED_LIMIT, "enough bits");
2092   int recompile_bit = (trap_state & DS_RECOMPILE_BIT);
2093   trap_state -= recompile_bit;
2094   if (trap_state == DS_REASON_MASK) {
2095     return -1;  // true, unspecifically (bottom of state lattice)
2096   } else if (trap_state == reason) {
2097     return 1;   // true, definitely
2098   } else if (trap_state == 0) {
2099     return 0;   // false, definitely (top of state lattice)
2100   } else {
2101     return 0;   // false, definitely
2102   }
2103 }
2104 //-------------------------trap_state_add_reason-------------------------------
2105 int Deoptimization::trap_state_add_reason(int trap_state, int reason) {
2106   assert(reason_is_recorded_per_bytecode((DeoptReason)reason) || reason == Reason_many, "valid reason");
2107   int recompile_bit = (trap_state & DS_RECOMPILE_BIT);
2108   trap_state -= recompile_bit;
2109   if (trap_state == DS_REASON_MASK) {
2110     return trap_state + recompile_bit;     // already at state lattice bottom
2111   } else if (trap_state == reason) {
2112     return trap_state + recompile_bit;     // the condition is already true
2113   } else if (trap_state == 0) {
2114     return reason + recompile_bit;          // no condition has yet been true
2115   } else {
2116     return DS_REASON_MASK + recompile_bit;  // fall to state lattice bottom
2117   }
2118 }
2119 //-----------------------trap_state_is_recompiled------------------------------
2120 bool Deoptimization::trap_state_is_recompiled(int trap_state) {
2121   return (trap_state & DS_RECOMPILE_BIT) != 0;
2122 }
2123 //-----------------------trap_state_set_recompiled-----------------------------
2124 int Deoptimization::trap_state_set_recompiled(int trap_state, bool z) {
2125   if (z)  return trap_state |  DS_RECOMPILE_BIT;
2126   else    return trap_state & ~DS_RECOMPILE_BIT;
2127 }
2128 //---------------------------format_trap_state---------------------------------
2129 // This is used for debugging and diagnostics, including LogFile output.
2130 const char* Deoptimization::format_trap_state(char* buf, size_t buflen,
2131                                               int trap_state) {
2132   assert(buflen > 0, "sanity");
2133   DeoptReason reason      = trap_state_reason(trap_state);
2134   bool        recomp_flag = trap_state_is_recompiled(trap_state);
2135   // Re-encode the state from its decoded components.
2136   int decoded_state = 0;
2137   if (reason_is_recorded_per_bytecode(reason) || reason == Reason_many)
2138     decoded_state = trap_state_add_reason(decoded_state, reason);
2139   if (recomp_flag)
2140     decoded_state = trap_state_set_recompiled(decoded_state, recomp_flag);
2141   // If the state re-encodes properly, format it symbolically.
2142   // Because this routine is used for debugging and diagnostics,
2143   // be robust even if the state is a strange value.
2144   size_t len;
2145   if (decoded_state != trap_state) {
2146     // Random buggy state that doesn't decode??
2147     len = jio_snprintf(buf, buflen, "#%d", trap_state);
2148   } else {
2149     len = jio_snprintf(buf, buflen, "%s%s",
2150                        trap_reason_name(reason),
2151                        recomp_flag ? " recompiled" : "");
2152   }
2153   return buf;
2154 }
2155 
2156 
2157 //--------------------------------statics--------------------------------------
2158 const char* Deoptimization::_trap_reason_name[] = {
2159   // Note:  Keep this in sync. with enum DeoptReason.
2160   "none",
2161   "null_check",
2162   "null_assert" JVMCI_ONLY("_or_unreached0"),
2163   "range_check",
2164   "class_check",
2165   "array_check",
2166   "intrinsic" JVMCI_ONLY("_or_type_checked_inlining"),
2167   "bimorphic" JVMCI_ONLY("_or_optimized_type_check"),
2168   "unloaded",
2169   "uninitialized",
2170   "unreached",
2171   "unhandled",
2172   "constraint",
2173   "div0_check",
2174   "age",
2175   "predicate",
2176   "loop_limit_check",
2177   "speculate_class_check",
2178   "speculate_null_check",
2179   "speculate_null_assert",
2180   "rtm_state_change",
2181   "unstable_if",
2182   "unstable_fused_if",
2183 #if INCLUDE_JVMCI
2184   "aliasing",
2185   "transfer_to_interpreter",
2186   "not_compiled_exception_handler",
2187   "unresolved",
2188   "jsr_mismatch",
2189 #endif
2190   "tenured"
2191 };
2192 const char* Deoptimization::_trap_action_name[] = {
2193   // Note:  Keep this in sync. with enum DeoptAction.
2194   "none",
2195   "maybe_recompile",
2196   "reinterpret",
2197   "make_not_entrant",
2198   "make_not_compilable"
2199 };
2200 
2201 const char* Deoptimization::trap_reason_name(int reason) {
2202   // Check that every reason has a name
2203   STATIC_ASSERT(sizeof(_trap_reason_name)/sizeof(const char*) == Reason_LIMIT);
2204 
2205   if (reason == Reason_many)  return "many";
2206   if ((uint)reason < Reason_LIMIT)
2207     return _trap_reason_name[reason];
2208   static char buf[20];
2209   sprintf(buf, "reason%d", reason);
2210   return buf;
2211 }
2212 const char* Deoptimization::trap_action_name(int action) {
2213   // Check that every action has a name
2214   STATIC_ASSERT(sizeof(_trap_action_name)/sizeof(const char*) == Action_LIMIT);
2215 
2216   if ((uint)action < Action_LIMIT)
2217     return _trap_action_name[action];
2218   static char buf[20];
2219   sprintf(buf, "action%d", action);
2220   return buf;
2221 }
2222 
2223 // This is used for debugging and diagnostics, including LogFile output.
2224 const char* Deoptimization::format_trap_request(char* buf, size_t buflen,
2225                                                 int trap_request) {
2226   jint unloaded_class_index = trap_request_index(trap_request);
2227   const char* reason = trap_reason_name(trap_request_reason(trap_request));
2228   const char* action = trap_action_name(trap_request_action(trap_request));
2229 #if INCLUDE_JVMCI
2230   int debug_id = trap_request_debug_id(trap_request);
2231 #endif
2232   size_t len;
2233   if (unloaded_class_index < 0) {
2234     len = jio_snprintf(buf, buflen, "reason='%s' action='%s'" JVMCI_ONLY(" debug_id='%d'"),
2235                        reason, action
2236 #if INCLUDE_JVMCI
2237                        ,debug_id
2238 #endif
2239                        );
2240   } else {
2241     len = jio_snprintf(buf, buflen, "reason='%s' action='%s' index='%d'" JVMCI_ONLY(" debug_id='%d'"),
2242                        reason, action, unloaded_class_index
2243 #if INCLUDE_JVMCI
2244                        ,debug_id
2245 #endif
2246                        );
2247   }
2248   return buf;
2249 }
2250 
2251 juint Deoptimization::_deoptimization_hist
2252         [Deoptimization::Reason_LIMIT]
2253     [1 + Deoptimization::Action_LIMIT]
2254         [Deoptimization::BC_CASE_LIMIT]
2255   = {0};
2256 
2257 enum {
2258   LSB_BITS = 8,
2259   LSB_MASK = right_n_bits(LSB_BITS)
2260 };
2261 
2262 void Deoptimization::gather_statistics(DeoptReason reason, DeoptAction action,
2263                                        Bytecodes::Code bc) {
2264   assert(reason >= 0 && reason < Reason_LIMIT, "oob");
2265   assert(action >= 0 && action < Action_LIMIT, "oob");
2266   _deoptimization_hist[Reason_none][0][0] += 1;  // total
2267   _deoptimization_hist[reason][0][0]      += 1;  // per-reason total
2268   juint* cases = _deoptimization_hist[reason][1+action];
2269   juint* bc_counter_addr = NULL;
2270   juint  bc_counter      = 0;
2271   // Look for an unused counter, or an exact match to this BC.
2272   if (bc != Bytecodes::_illegal) {
2273     for (int bc_case = 0; bc_case < BC_CASE_LIMIT; bc_case++) {
2274       juint* counter_addr = &cases[bc_case];
2275       juint  counter = *counter_addr;
2276       if ((counter == 0 && bc_counter_addr == NULL)
2277           || (Bytecodes::Code)(counter & LSB_MASK) == bc) {
2278         // this counter is either free or is already devoted to this BC
2279         bc_counter_addr = counter_addr;
2280         bc_counter = counter | bc;
2281       }
2282     }
2283   }
2284   if (bc_counter_addr == NULL) {
2285     // Overflow, or no given bytecode.
2286     bc_counter_addr = &cases[BC_CASE_LIMIT-1];
2287     bc_counter = (*bc_counter_addr & ~LSB_MASK);  // clear LSB
2288   }
2289   *bc_counter_addr = bc_counter + (1 << LSB_BITS);
2290 }
2291 
2292 jint Deoptimization::total_deoptimization_count() {
2293   return _deoptimization_hist[Reason_none][0][0];
2294 }
2295 
2296 jint Deoptimization::deoptimization_count(DeoptReason reason) {
2297   assert(reason >= 0 && reason < Reason_LIMIT, "oob");
2298   return _deoptimization_hist[reason][0][0];
2299 }
2300 
2301 void Deoptimization::print_statistics() {
2302   juint total = total_deoptimization_count();
2303   juint account = total;
2304   if (total != 0) {
2305     ttyLocker ttyl;
2306     if (xtty != NULL)  xtty->head("statistics type='deoptimization'");
2307     tty->print_cr("Deoptimization traps recorded:");
2308     #define PRINT_STAT_LINE(name, r) \
2309       tty->print_cr("  %4d (%4.1f%%) %s", (int)(r), ((r) * 100.0) / total, name);
2310     PRINT_STAT_LINE("total", total);
2311     // For each non-zero entry in the histogram, print the reason,
2312     // the action, and (if specifically known) the type of bytecode.
2313     for (int reason = 0; reason < Reason_LIMIT; reason++) {
2314       for (int action = 0; action < Action_LIMIT; action++) {
2315         juint* cases = _deoptimization_hist[reason][1+action];
2316         for (int bc_case = 0; bc_case < BC_CASE_LIMIT; bc_case++) {
2317           juint counter = cases[bc_case];
2318           if (counter != 0) {
2319             char name[1*K];
2320             Bytecodes::Code bc = (Bytecodes::Code)(counter & LSB_MASK);
2321             if (bc_case == BC_CASE_LIMIT && (int)bc == 0)
2322               bc = Bytecodes::_illegal;
2323             sprintf(name, "%s/%s/%s",
2324                     trap_reason_name(reason),
2325                     trap_action_name(action),
2326                     Bytecodes::is_defined(bc)? Bytecodes::name(bc): "other");
2327             juint r = counter >> LSB_BITS;
2328             tty->print_cr("  %40s: " UINT32_FORMAT " (%.1f%%)", name, r, (r * 100.0) / total);
2329             account -= r;
2330           }
2331         }
2332       }
2333     }
2334     if (account != 0) {
2335       PRINT_STAT_LINE("unaccounted", account);
2336     }
2337     #undef PRINT_STAT_LINE
2338     if (xtty != NULL)  xtty->tail("statistics");
2339   }
2340 }
2341 #else // COMPILER2_OR_JVMCI
2342 
2343 
2344 // Stubs for C1 only system.
2345 bool Deoptimization::trap_state_is_recompiled(int trap_state) {
2346   return false;
2347 }
2348 
2349 const char* Deoptimization::trap_reason_name(int reason) {
2350   return "unknown";
2351 }
2352 
2353 void Deoptimization::print_statistics() {
2354   // no output
2355 }
2356 
2357 void
2358 Deoptimization::update_method_data_from_interpreter(MethodData* trap_mdo, int trap_bci, int reason) {
2359   // no udpate
2360 }
2361 
2362 int Deoptimization::trap_state_has_reason(int trap_state, int reason) {
2363   return 0;
2364 }
2365 
2366 void Deoptimization::gather_statistics(DeoptReason reason, DeoptAction action,
2367                                        Bytecodes::Code bc) {
2368   // no update
2369 }
2370 
2371 const char* Deoptimization::format_trap_state(char* buf, size_t buflen,
2372                                               int trap_state) {
2373   jio_snprintf(buf, buflen, "#%d", trap_state);
2374   return buf;
2375 }
2376 
2377 #endif // COMPILER2_OR_JVMCI