rev 48535 : [mq]: 8194990

   1 /*
   2  * Copyright (c) 1997, 2018, 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 "code/codeCache.hpp"
  28 #include "code/compiledIC.hpp"
  29 #include "code/dependencies.hpp"
  30 #include "code/nativeInst.hpp"
  31 #include "code/nmethod.hpp"
  32 #include "code/scopeDesc.hpp"
  33 #include "compiler/abstractCompiler.hpp"
  34 #include "compiler/compileBroker.hpp"
  35 #include "compiler/compileLog.hpp"
  36 #include "compiler/compilerDirectives.hpp"
  37 #include "compiler/directivesParser.hpp"
  38 #include "compiler/disassembler.hpp"
  39 #include "interpreter/bytecode.hpp"
  40 #include "logging/log.hpp"
  41 #include "logging/logStream.hpp"
  42 #include "memory/resourceArea.hpp"
  43 #include "oops/methodData.hpp"
  44 #include "oops/oop.inline.hpp"
  45 #include "prims/jvmtiImpl.hpp"
  46 #include "runtime/atomic.hpp"
  47 #include "runtime/orderAccess.inline.hpp"
  48 #include "runtime/os.hpp"
  49 #include "runtime/sharedRuntime.hpp"
  50 #include "runtime/sweeper.hpp"
  51 #include "utilities/align.hpp"
  52 #include "utilities/dtrace.hpp"
  53 #include "utilities/events.hpp"
  54 #include "utilities/resourceHash.hpp"
  55 #include "utilities/xmlstream.hpp"
  56 #if INCLUDE_JVMCI
  57 #include "jvmci/jvmciJavaClasses.hpp"
  58 #endif
  59 
  60 #ifdef DTRACE_ENABLED
  61 
  62 // Only bother with this argument setup if dtrace is available
  63 
  64 #define DTRACE_METHOD_UNLOAD_PROBE(method)                                \
  65   {                                                                       \
  66     Method* m = (method);                                                 \
  67     if (m != NULL) {                                                      \
  68       Symbol* klass_name = m->klass_name();                               \
  69       Symbol* name = m->name();                                           \
  70       Symbol* signature = m->signature();                                 \
  71       HOTSPOT_COMPILED_METHOD_UNLOAD(                                     \
  72         (char *) klass_name->bytes(), klass_name->utf8_length(),                   \
  73         (char *) name->bytes(), name->utf8_length(),                               \
  74         (char *) signature->bytes(), signature->utf8_length());                    \
  75     }                                                                     \
  76   }
  77 
  78 #else //  ndef DTRACE_ENABLED
  79 
  80 #define DTRACE_METHOD_UNLOAD_PROBE(method)
  81 
  82 #endif
  83 
  84 //---------------------------------------------------------------------------------
  85 // NMethod statistics
  86 // They are printed under various flags, including:
  87 //   PrintC1Statistics, PrintOptoStatistics, LogVMOutput, and LogCompilation.
  88 // (In the latter two cases, they like other stats are printed to the log only.)
  89 
  90 #ifndef PRODUCT
  91 // These variables are put into one block to reduce relocations
  92 // and make it simpler to print from the debugger.
  93 struct java_nmethod_stats_struct {
  94   int nmethod_count;
  95   int total_size;
  96   int relocation_size;
  97   int consts_size;
  98   int insts_size;
  99   int stub_size;
 100   int scopes_data_size;
 101   int scopes_pcs_size;
 102   int dependencies_size;
 103   int handler_table_size;
 104   int nul_chk_table_size;
 105   int oops_size;
 106   int metadata_size;
 107 
 108   void note_nmethod(nmethod* nm) {
 109     nmethod_count += 1;
 110     total_size          += nm->size();
 111     relocation_size     += nm->relocation_size();
 112     consts_size         += nm->consts_size();
 113     insts_size          += nm->insts_size();
 114     stub_size           += nm->stub_size();
 115     oops_size           += nm->oops_size();
 116     metadata_size       += nm->metadata_size();
 117     scopes_data_size    += nm->scopes_data_size();
 118     scopes_pcs_size     += nm->scopes_pcs_size();
 119     dependencies_size   += nm->dependencies_size();
 120     handler_table_size  += nm->handler_table_size();
 121     nul_chk_table_size  += nm->nul_chk_table_size();
 122   }
 123   void print_nmethod_stats(const char* name) {
 124     if (nmethod_count == 0)  return;
 125     tty->print_cr("Statistics for %d bytecoded nmethods for %s:", nmethod_count, name);
 126     if (total_size != 0)          tty->print_cr(" total in heap  = %d", total_size);
 127     if (nmethod_count != 0)       tty->print_cr(" header         = " SIZE_FORMAT, nmethod_count * sizeof(nmethod));
 128     if (relocation_size != 0)     tty->print_cr(" relocation     = %d", relocation_size);
 129     if (consts_size != 0)         tty->print_cr(" constants      = %d", consts_size);
 130     if (insts_size != 0)          tty->print_cr(" main code      = %d", insts_size);
 131     if (stub_size != 0)           tty->print_cr(" stub code      = %d", stub_size);
 132     if (oops_size != 0)           tty->print_cr(" oops           = %d", oops_size);
 133     if (metadata_size != 0)       tty->print_cr(" metadata       = %d", metadata_size);
 134     if (scopes_data_size != 0)    tty->print_cr(" scopes data    = %d", scopes_data_size);
 135     if (scopes_pcs_size != 0)     tty->print_cr(" scopes pcs     = %d", scopes_pcs_size);
 136     if (dependencies_size != 0)   tty->print_cr(" dependencies   = %d", dependencies_size);
 137     if (handler_table_size != 0)  tty->print_cr(" handler table  = %d", handler_table_size);
 138     if (nul_chk_table_size != 0)  tty->print_cr(" nul chk table  = %d", nul_chk_table_size);
 139   }
 140 };
 141 
 142 struct native_nmethod_stats_struct {
 143   int native_nmethod_count;
 144   int native_total_size;
 145   int native_relocation_size;
 146   int native_insts_size;
 147   int native_oops_size;
 148   int native_metadata_size;
 149   void note_native_nmethod(nmethod* nm) {
 150     native_nmethod_count += 1;
 151     native_total_size       += nm->size();
 152     native_relocation_size  += nm->relocation_size();
 153     native_insts_size       += nm->insts_size();
 154     native_oops_size        += nm->oops_size();
 155     native_metadata_size    += nm->metadata_size();
 156   }
 157   void print_native_nmethod_stats() {
 158     if (native_nmethod_count == 0)  return;
 159     tty->print_cr("Statistics for %d native nmethods:", native_nmethod_count);
 160     if (native_total_size != 0)       tty->print_cr(" N. total size  = %d", native_total_size);
 161     if (native_relocation_size != 0)  tty->print_cr(" N. relocation  = %d", native_relocation_size);
 162     if (native_insts_size != 0)       tty->print_cr(" N. main code   = %d", native_insts_size);
 163     if (native_oops_size != 0)        tty->print_cr(" N. oops        = %d", native_oops_size);
 164     if (native_metadata_size != 0)    tty->print_cr(" N. metadata    = %d", native_metadata_size);
 165   }
 166 };
 167 
 168 struct pc_nmethod_stats_struct {
 169   int pc_desc_resets;   // number of resets (= number of caches)
 170   int pc_desc_queries;  // queries to nmethod::find_pc_desc
 171   int pc_desc_approx;   // number of those which have approximate true
 172   int pc_desc_repeats;  // number of _pc_descs[0] hits
 173   int pc_desc_hits;     // number of LRU cache hits
 174   int pc_desc_tests;    // total number of PcDesc examinations
 175   int pc_desc_searches; // total number of quasi-binary search steps
 176   int pc_desc_adds;     // number of LUR cache insertions
 177 
 178   void print_pc_stats() {
 179     tty->print_cr("PcDesc Statistics:  %d queries, %.2f comparisons per query",
 180                   pc_desc_queries,
 181                   (double)(pc_desc_tests + pc_desc_searches)
 182                   / pc_desc_queries);
 183     tty->print_cr("  caches=%d queries=%d/%d, hits=%d+%d, tests=%d+%d, adds=%d",
 184                   pc_desc_resets,
 185                   pc_desc_queries, pc_desc_approx,
 186                   pc_desc_repeats, pc_desc_hits,
 187                   pc_desc_tests, pc_desc_searches, pc_desc_adds);
 188   }
 189 };
 190 
 191 #ifdef COMPILER1
 192 static java_nmethod_stats_struct c1_java_nmethod_stats;
 193 #endif
 194 #ifdef COMPILER2
 195 static java_nmethod_stats_struct c2_java_nmethod_stats;
 196 #endif
 197 #if INCLUDE_JVMCI
 198 static java_nmethod_stats_struct jvmci_java_nmethod_stats;
 199 #endif
 200 static java_nmethod_stats_struct unknown_java_nmethod_stats;
 201 
 202 static native_nmethod_stats_struct native_nmethod_stats;
 203 static pc_nmethod_stats_struct pc_nmethod_stats;
 204 
 205 static void note_java_nmethod(nmethod* nm) {
 206 #ifdef COMPILER1
 207   if (nm->is_compiled_by_c1()) {
 208     c1_java_nmethod_stats.note_nmethod(nm);
 209   } else
 210 #endif
 211 #ifdef COMPILER2
 212   if (nm->is_compiled_by_c2()) {
 213     c2_java_nmethod_stats.note_nmethod(nm);
 214   } else
 215 #endif
 216 #if INCLUDE_JVMCI
 217   if (nm->is_compiled_by_jvmci()) {
 218     jvmci_java_nmethod_stats.note_nmethod(nm);
 219   } else
 220 #endif
 221   {
 222     unknown_java_nmethod_stats.note_nmethod(nm);
 223   }
 224 }
 225 #endif // !PRODUCT
 226 
 227 //---------------------------------------------------------------------------------
 228 
 229 
 230 ExceptionCache::ExceptionCache(Handle exception, address pc, address handler) {
 231   assert(pc != NULL, "Must be non null");
 232   assert(exception.not_null(), "Must be non null");
 233   assert(handler != NULL, "Must be non null");
 234 
 235   _count = 0;
 236   _exception_type = exception->klass();
 237   _next = NULL;
 238 
 239   add_address_and_handler(pc,handler);
 240 }
 241 
 242 
 243 address ExceptionCache::match(Handle exception, address pc) {
 244   assert(pc != NULL,"Must be non null");
 245   assert(exception.not_null(),"Must be non null");
 246   if (exception->klass() == exception_type()) {
 247     return (test_address(pc));
 248   }
 249 
 250   return NULL;
 251 }
 252 
 253 
 254 bool ExceptionCache::match_exception_with_space(Handle exception) {
 255   assert(exception.not_null(),"Must be non null");
 256   if (exception->klass() == exception_type() && count() < cache_size) {
 257     return true;
 258   }
 259   return false;
 260 }
 261 
 262 
 263 address ExceptionCache::test_address(address addr) {
 264   int limit = count();
 265   for (int i = 0; i < limit; i++) {
 266     if (pc_at(i) == addr) {
 267       return handler_at(i);
 268     }
 269   }
 270   return NULL;
 271 }
 272 
 273 
 274 bool ExceptionCache::add_address_and_handler(address addr, address handler) {
 275   if (test_address(addr) == handler) return true;
 276 
 277   int index = count();
 278   if (index < cache_size) {
 279     set_pc_at(index, addr);
 280     set_handler_at(index, handler);
 281     increment_count();
 282     return true;
 283   }
 284   return false;
 285 }
 286 
 287 //-----------------------------------------------------------------------------
 288 
 289 
 290 // Helper used by both find_pc_desc methods.
 291 static inline bool match_desc(PcDesc* pc, int pc_offset, bool approximate) {
 292   NOT_PRODUCT(++pc_nmethod_stats.pc_desc_tests);
 293   if (!approximate)
 294     return pc->pc_offset() == pc_offset;
 295   else
 296     return (pc-1)->pc_offset() < pc_offset && pc_offset <= pc->pc_offset();
 297 }
 298 
 299 void PcDescCache::reset_to(PcDesc* initial_pc_desc) {
 300   if (initial_pc_desc == NULL) {
 301     _pc_descs[0] = NULL; // native method; no PcDescs at all
 302     return;
 303   }
 304   NOT_PRODUCT(++pc_nmethod_stats.pc_desc_resets);
 305   // reset the cache by filling it with benign (non-null) values
 306   assert(initial_pc_desc->pc_offset() < 0, "must be sentinel");
 307   for (int i = 0; i < cache_size; i++)
 308     _pc_descs[i] = initial_pc_desc;
 309 }
 310 
 311 PcDesc* PcDescCache::find_pc_desc(int pc_offset, bool approximate) {
 312   NOT_PRODUCT(++pc_nmethod_stats.pc_desc_queries);
 313   NOT_PRODUCT(if (approximate) ++pc_nmethod_stats.pc_desc_approx);
 314 
 315   // Note: one might think that caching the most recently
 316   // read value separately would be a win, but one would be
 317   // wrong.  When many threads are updating it, the cache
 318   // line it's in would bounce between caches, negating
 319   // any benefit.
 320 
 321   // In order to prevent race conditions do not load cache elements
 322   // repeatedly, but use a local copy:
 323   PcDesc* res;
 324 
 325   // Step one:  Check the most recently added value.
 326   res = _pc_descs[0];
 327   if (res == NULL) return NULL;  // native method; no PcDescs at all
 328   if (match_desc(res, pc_offset, approximate)) {
 329     NOT_PRODUCT(++pc_nmethod_stats.pc_desc_repeats);
 330     return res;
 331   }
 332 
 333   // Step two:  Check the rest of the LRU cache.
 334   for (int i = 1; i < cache_size; ++i) {
 335     res = _pc_descs[i];
 336     if (res->pc_offset() < 0) break;  // optimization: skip empty cache
 337     if (match_desc(res, pc_offset, approximate)) {
 338       NOT_PRODUCT(++pc_nmethod_stats.pc_desc_hits);
 339       return res;
 340     }
 341   }
 342 
 343   // Report failure.
 344   return NULL;
 345 }
 346 
 347 void PcDescCache::add_pc_desc(PcDesc* pc_desc) {
 348   NOT_PRODUCT(++pc_nmethod_stats.pc_desc_adds);
 349   // Update the LRU cache by shifting pc_desc forward.
 350   for (int i = 0; i < cache_size; i++)  {
 351     PcDesc* next = _pc_descs[i];
 352     _pc_descs[i] = pc_desc;
 353     pc_desc = next;
 354   }
 355 }
 356 
 357 // adjust pcs_size so that it is a multiple of both oopSize and
 358 // sizeof(PcDesc) (assumes that if sizeof(PcDesc) is not a multiple
 359 // of oopSize, then 2*sizeof(PcDesc) is)
 360 static int adjust_pcs_size(int pcs_size) {
 361   int nsize = align_up(pcs_size,   oopSize);
 362   if ((nsize % sizeof(PcDesc)) != 0) {
 363     nsize = pcs_size + sizeof(PcDesc);
 364   }
 365   assert((nsize % oopSize) == 0, "correct alignment");
 366   return nsize;
 367 }
 368 
 369 
 370 int nmethod::total_size() const {
 371   return
 372     consts_size()        +
 373     insts_size()         +
 374     stub_size()          +
 375     scopes_data_size()   +
 376     scopes_pcs_size()    +
 377     handler_table_size() +
 378     nul_chk_table_size();
 379 }
 380 
 381 const char* nmethod::compile_kind() const {
 382   if (is_osr_method())     return "osr";
 383   if (method() != NULL && is_native_method())  return "c2n";
 384   return NULL;
 385 }
 386 
 387 // Fill in default values for various flag fields
 388 void nmethod::init_defaults() {
 389   _state                      = not_installed;
 390   _has_flushed_dependencies   = 0;
 391   _lock_count                 = 0;
 392   _stack_traversal_mark       = 0;
 393   _unload_reported            = false; // jvmti state
 394   _is_far_code                = false; // nmethods are located in CodeCache
 395 
 396 #ifdef ASSERT
 397   _oops_are_stale             = false;
 398 #endif
 399 
 400   _oops_do_mark_link       = NULL;
 401   _jmethod_id              = NULL;
 402   _osr_link                = NULL;
 403   _unloading_next          = NULL;
 404   _scavenge_root_link      = NULL;
 405   _scavenge_root_state     = 0;
 406 #if INCLUDE_RTM_OPT
 407   _rtm_state               = NoRTM;
 408 #endif
 409 #if INCLUDE_JVMCI
 410   _jvmci_installed_code   = NULL;
 411   _speculation_log        = NULL;
 412   _jvmci_installed_code_triggers_unloading = false;
 413 #endif
 414 }
 415 
 416 nmethod* nmethod::new_native_nmethod(const methodHandle& method,
 417   int compile_id,
 418   CodeBuffer *code_buffer,
 419   int vep_offset,
 420   int frame_complete,
 421   int frame_size,
 422   ByteSize basic_lock_owner_sp_offset,
 423   ByteSize basic_lock_sp_offset,
 424   OopMapSet* oop_maps) {
 425   code_buffer->finalize_oop_references(method);
 426   // create nmethod
 427   nmethod* nm = NULL;
 428   {
 429     MutexLockerEx mu(CodeCache_lock, Mutex::_no_safepoint_check_flag);
 430     int native_nmethod_size = CodeBlob::allocation_size(code_buffer, sizeof(nmethod));
 431     CodeOffsets offsets;
 432     offsets.set_value(CodeOffsets::Verified_Entry, vep_offset);
 433     offsets.set_value(CodeOffsets::Frame_Complete, frame_complete);
 434     nm = new (native_nmethod_size, CompLevel_none) nmethod(method(), compiler_none, native_nmethod_size,
 435                                             compile_id, &offsets,
 436                                             code_buffer, frame_size,
 437                                             basic_lock_owner_sp_offset,
 438                                             basic_lock_sp_offset, oop_maps);
 439     NOT_PRODUCT(if (nm != NULL)  native_nmethod_stats.note_native_nmethod(nm));
 440   }
 441 
 442   if (nm != NULL) {
 443     // verify nmethod
 444     debug_only(nm->verify();) // might block
 445 
 446     nm->log_new_nmethod();
 447     nm->make_in_use();
 448   }
 449   return nm;
 450 }
 451 
 452 nmethod* nmethod::new_nmethod(const methodHandle& method,
 453   int compile_id,
 454   int entry_bci,
 455   CodeOffsets* offsets,
 456   int orig_pc_offset,
 457   DebugInformationRecorder* debug_info,
 458   Dependencies* dependencies,
 459   CodeBuffer* code_buffer, int frame_size,
 460   OopMapSet* oop_maps,
 461   ExceptionHandlerTable* handler_table,
 462   ImplicitExceptionTable* nul_chk_table,
 463   AbstractCompiler* compiler,
 464   int comp_level
 465 #if INCLUDE_JVMCI
 466   , jweak installed_code,
 467   jweak speculationLog
 468 #endif
 469 )
 470 {
 471   assert(debug_info->oop_recorder() == code_buffer->oop_recorder(), "shared OR");
 472   code_buffer->finalize_oop_references(method);
 473   // create nmethod
 474   nmethod* nm = NULL;
 475   { MutexLockerEx mu(CodeCache_lock, Mutex::_no_safepoint_check_flag);
 476     int nmethod_size =
 477       CodeBlob::allocation_size(code_buffer, sizeof(nmethod))
 478       + adjust_pcs_size(debug_info->pcs_size())
 479       + align_up((int)dependencies->size_in_bytes(), oopSize)
 480       + align_up(handler_table->size_in_bytes()    , oopSize)
 481       + align_up(nul_chk_table->size_in_bytes()    , oopSize)
 482       + align_up(debug_info->data_size()           , oopSize);
 483 
 484     nm = new (nmethod_size, comp_level)
 485     nmethod(method(), compiler->type(), nmethod_size, compile_id, entry_bci, offsets,
 486             orig_pc_offset, debug_info, dependencies, code_buffer, frame_size,
 487             oop_maps,
 488             handler_table,
 489             nul_chk_table,
 490             compiler,
 491             comp_level
 492 #if INCLUDE_JVMCI
 493             , installed_code,
 494             speculationLog
 495 #endif
 496             );
 497 
 498     if (nm != NULL) {
 499       // To make dependency checking during class loading fast, record
 500       // the nmethod dependencies in the classes it is dependent on.
 501       // This allows the dependency checking code to simply walk the
 502       // class hierarchy above the loaded class, checking only nmethods
 503       // which are dependent on those classes.  The slow way is to
 504       // check every nmethod for dependencies which makes it linear in
 505       // the number of methods compiled.  For applications with a lot
 506       // classes the slow way is too slow.
 507       for (Dependencies::DepStream deps(nm); deps.next(); ) {
 508         if (deps.type() == Dependencies::call_site_target_value) {
 509           // CallSite dependencies are managed on per-CallSite instance basis.
 510           oop call_site = deps.argument_oop(0);
 511           MethodHandles::add_dependent_nmethod(call_site, nm);
 512         } else {
 513           Klass* klass = deps.context_type();
 514           if (klass == NULL) {
 515             continue;  // ignore things like evol_method
 516           }
 517           // record this nmethod as dependent on this klass
 518           InstanceKlass::cast(klass)->add_dependent_nmethod(nm);
 519         }
 520       }
 521       NOT_PRODUCT(if (nm != NULL)  note_java_nmethod(nm));
 522     }
 523   }
 524   // Do verification and logging outside CodeCache_lock.
 525   if (nm != NULL) {
 526     // Safepoints in nmethod::verify aren't allowed because nm hasn't been installed yet.
 527     DEBUG_ONLY(nm->verify();)
 528     nm->log_new_nmethod();
 529   }
 530   return nm;
 531 }
 532 
 533 // For native wrappers
 534 nmethod::nmethod(
 535   Method* method,
 536   CompilerType type,
 537   int nmethod_size,
 538   int compile_id,
 539   CodeOffsets* offsets,
 540   CodeBuffer* code_buffer,
 541   int frame_size,
 542   ByteSize basic_lock_owner_sp_offset,
 543   ByteSize basic_lock_sp_offset,
 544   OopMapSet* oop_maps )
 545   : CompiledMethod(method, "native nmethod", type, nmethod_size, sizeof(nmethod), code_buffer, offsets->value(CodeOffsets::Frame_Complete), frame_size, oop_maps, false),
 546   _native_receiver_sp_offset(basic_lock_owner_sp_offset),
 547   _native_basic_lock_sp_offset(basic_lock_sp_offset)
 548 {
 549   {
 550     int scopes_data_offset = 0;
 551     int deoptimize_offset       = 0;
 552     int deoptimize_mh_offset    = 0;
 553 
 554     debug_only(NoSafepointVerifier nsv;)
 555     assert_locked_or_safepoint(CodeCache_lock);
 556 
 557     init_defaults();
 558     _entry_bci               = InvocationEntryBci;
 559     // We have no exception handler or deopt handler make the
 560     // values something that will never match a pc like the nmethod vtable entry
 561     _exception_offset        = 0;
 562     _orig_pc_offset          = 0;
 563 
 564     _consts_offset           = data_offset();
 565     _stub_offset             = data_offset();
 566     _oops_offset             = data_offset();
 567     _metadata_offset         = _oops_offset         + align_up(code_buffer->total_oop_size(), oopSize);
 568     scopes_data_offset       = _metadata_offset     + align_up(code_buffer->total_metadata_size(), wordSize);
 569     _scopes_pcs_offset       = scopes_data_offset;
 570     _dependencies_offset     = _scopes_pcs_offset;
 571     _handler_table_offset    = _dependencies_offset;
 572     _nul_chk_table_offset    = _handler_table_offset;
 573     _nmethod_end_offset      = _nul_chk_table_offset;
 574     _compile_id              = compile_id;
 575     _comp_level              = CompLevel_none;
 576     _entry_point             = code_begin()          + offsets->value(CodeOffsets::Entry);
 577     _verified_entry_point    = code_begin()          + offsets->value(CodeOffsets::Verified_Entry);
 578     _osr_entry_point         = NULL;
 579     _exception_cache         = NULL;
 580     _pc_desc_container.reset_to(NULL);
 581     _hotness_counter         = NMethodSweeper::hotness_counter_reset_val();
 582 
 583     _scopes_data_begin = (address) this + scopes_data_offset;
 584     _deopt_handler_begin = (address) this + deoptimize_offset;
 585     _deopt_mh_handler_begin = (address) this + deoptimize_mh_offset;
 586 
 587     code_buffer->copy_code_and_locs_to(this);
 588     code_buffer->copy_values_to(this);
 589     if (ScavengeRootsInCode) {
 590       Universe::heap()->register_nmethod(this);
 591     }
 592     debug_only(Universe::heap()->verify_nmethod(this));
 593     CodeCache::commit(this);
 594   }
 595 
 596   if (PrintNativeNMethods || PrintDebugInfo || PrintRelocations || PrintDependencies) {
 597     ttyLocker ttyl;  // keep the following output all in one block
 598     // This output goes directly to the tty, not the compiler log.
 599     // To enable tools to match it up with the compilation activity,
 600     // be sure to tag this tty output with the compile ID.
 601     if (xtty != NULL) {
 602       xtty->begin_head("print_native_nmethod");
 603       xtty->method(_method);
 604       xtty->stamp();
 605       xtty->end_head(" address='" INTPTR_FORMAT "'", (intptr_t) this);
 606     }
 607     // print the header part first
 608     print();
 609     // then print the requested information
 610     if (PrintNativeNMethods) {
 611       print_code();
 612       if (oop_maps != NULL) {
 613         oop_maps->print();
 614       }
 615     }
 616     if (PrintRelocations) {
 617       print_relocations();
 618     }
 619     if (xtty != NULL) {
 620       xtty->tail("print_native_nmethod");
 621     }
 622   }
 623 }
 624 
 625 void* nmethod::operator new(size_t size, int nmethod_size, int comp_level) throw () {
 626   return CodeCache::allocate(nmethod_size, CodeCache::get_code_blob_type(comp_level));
 627 }
 628 
 629 nmethod::nmethod(
 630   Method* method,
 631   CompilerType type,
 632   int nmethod_size,
 633   int compile_id,
 634   int entry_bci,
 635   CodeOffsets* offsets,
 636   int orig_pc_offset,
 637   DebugInformationRecorder* debug_info,
 638   Dependencies* dependencies,
 639   CodeBuffer *code_buffer,
 640   int frame_size,
 641   OopMapSet* oop_maps,
 642   ExceptionHandlerTable* handler_table,
 643   ImplicitExceptionTable* nul_chk_table,
 644   AbstractCompiler* compiler,
 645   int comp_level
 646 #if INCLUDE_JVMCI
 647   , jweak installed_code,
 648   jweak speculation_log
 649 #endif
 650   )
 651   : CompiledMethod(method, "nmethod", type, nmethod_size, sizeof(nmethod), code_buffer, offsets->value(CodeOffsets::Frame_Complete), frame_size, oop_maps, false),
 652   _native_receiver_sp_offset(in_ByteSize(-1)),
 653   _native_basic_lock_sp_offset(in_ByteSize(-1))
 654 {
 655   assert(debug_info->oop_recorder() == code_buffer->oop_recorder(), "shared OR");
 656   {
 657     debug_only(NoSafepointVerifier nsv;)
 658     assert_locked_or_safepoint(CodeCache_lock);
 659 
 660     _deopt_handler_begin = (address) this;
 661     _deopt_mh_handler_begin = (address) this;
 662 
 663     init_defaults();
 664     _entry_bci               = entry_bci;
 665     _compile_id              = compile_id;
 666     _comp_level              = comp_level;
 667     _orig_pc_offset          = orig_pc_offset;
 668     _hotness_counter         = NMethodSweeper::hotness_counter_reset_val();
 669 
 670     // Section offsets
 671     _consts_offset           = content_offset()      + code_buffer->total_offset_of(code_buffer->consts());
 672     _stub_offset             = content_offset()      + code_buffer->total_offset_of(code_buffer->stubs());
 673     set_ctable_begin(header_begin() + _consts_offset);
 674 
 675 #if INCLUDE_JVMCI
 676     _jvmci_installed_code = installed_code;
 677     _speculation_log = speculation_log;
 678     oop obj = JNIHandles::resolve(installed_code);
 679     if (obj == NULL || (obj->is_a(HotSpotNmethod::klass()) && HotSpotNmethod::isDefault(obj))) {
 680       _jvmci_installed_code_triggers_unloading = false;
 681     } else {
 682       _jvmci_installed_code_triggers_unloading = true;
 683     }
 684 
 685     if (compiler->is_jvmci()) {
 686       // JVMCI might not produce any stub sections
 687       if (offsets->value(CodeOffsets::Exceptions) != -1) {
 688         _exception_offset        = code_offset()          + offsets->value(CodeOffsets::Exceptions);
 689       } else {
 690         _exception_offset = -1;
 691       }
 692       if (offsets->value(CodeOffsets::Deopt) != -1) {
 693         _deopt_handler_begin       = (address) this + code_offset()          + offsets->value(CodeOffsets::Deopt);
 694       } else {
 695         _deopt_handler_begin = NULL;
 696       }
 697       if (offsets->value(CodeOffsets::DeoptMH) != -1) {
 698         _deopt_mh_handler_begin  = (address) this + code_offset()          + offsets->value(CodeOffsets::DeoptMH);
 699       } else {
 700         _deopt_mh_handler_begin = NULL;
 701       }
 702     } else {
 703 #endif
 704     // Exception handler and deopt handler are in the stub section
 705     assert(offsets->value(CodeOffsets::Exceptions) != -1, "must be set");
 706     assert(offsets->value(CodeOffsets::Deopt     ) != -1, "must be set");
 707 
 708     _exception_offset       = _stub_offset          + offsets->value(CodeOffsets::Exceptions);
 709     _deopt_handler_begin    = (address) this + _stub_offset          + offsets->value(CodeOffsets::Deopt);
 710     if (offsets->value(CodeOffsets::DeoptMH) != -1) {
 711       _deopt_mh_handler_begin  = (address) this + _stub_offset          + offsets->value(CodeOffsets::DeoptMH);
 712     } else {
 713       _deopt_mh_handler_begin  = NULL;
 714 #if INCLUDE_JVMCI
 715     }
 716 #endif
 717     }
 718     if (offsets->value(CodeOffsets::UnwindHandler) != -1) {
 719       _unwind_handler_offset = code_offset()         + offsets->value(CodeOffsets::UnwindHandler);
 720     } else {
 721       _unwind_handler_offset = -1;
 722     }
 723 
 724     _oops_offset             = data_offset();
 725     _metadata_offset         = _oops_offset          + align_up(code_buffer->total_oop_size(), oopSize);
 726     int scopes_data_offset   = _metadata_offset      + align_up(code_buffer->total_metadata_size(), wordSize);
 727 
 728     _scopes_pcs_offset       = scopes_data_offset    + align_up(debug_info->data_size       (), oopSize);
 729     _dependencies_offset     = _scopes_pcs_offset    + adjust_pcs_size(debug_info->pcs_size());
 730     _handler_table_offset    = _dependencies_offset  + align_up((int)dependencies->size_in_bytes (), oopSize);
 731     _nul_chk_table_offset    = _handler_table_offset + align_up(handler_table->size_in_bytes(), oopSize);
 732     _nmethod_end_offset      = _nul_chk_table_offset + align_up(nul_chk_table->size_in_bytes(), oopSize);
 733     _entry_point             = code_begin()          + offsets->value(CodeOffsets::Entry);
 734     _verified_entry_point    = code_begin()          + offsets->value(CodeOffsets::Verified_Entry);
 735     _osr_entry_point         = code_begin()          + offsets->value(CodeOffsets::OSR_Entry);
 736     _exception_cache         = NULL;
 737 
 738     _scopes_data_begin = (address) this + scopes_data_offset;
 739 
 740     _pc_desc_container.reset_to(scopes_pcs_begin());
 741 
 742     code_buffer->copy_code_and_locs_to(this);
 743     // Copy contents of ScopeDescRecorder to nmethod
 744     code_buffer->copy_values_to(this);
 745     debug_info->copy_to(this);
 746     dependencies->copy_to(this);
 747     if (ScavengeRootsInCode) {
 748       Universe::heap()->register_nmethod(this);
 749     }
 750     debug_only(Universe::heap()->verify_nmethod(this));
 751 
 752     CodeCache::commit(this);
 753 
 754     // Copy contents of ExceptionHandlerTable to nmethod
 755     handler_table->copy_to(this);
 756     nul_chk_table->copy_to(this);
 757 
 758     // we use the information of entry points to find out if a method is
 759     // static or non static
 760     assert(compiler->is_c2() || compiler->is_jvmci() ||
 761            _method->is_static() == (entry_point() == _verified_entry_point),
 762            " entry points must be same for static methods and vice versa");
 763   }
 764 }
 765 
 766 // Print a short set of xml attributes to identify this nmethod.  The
 767 // output should be embedded in some other element.
 768 void nmethod::log_identity(xmlStream* log) const {
 769   log->print(" compile_id='%d'", compile_id());
 770   const char* nm_kind = compile_kind();
 771   if (nm_kind != NULL)  log->print(" compile_kind='%s'", nm_kind);
 772   log->print(" compiler='%s'", compiler_name());
 773   if (TieredCompilation) {
 774     log->print(" level='%d'", comp_level());
 775   }
 776 }
 777 
 778 
 779 #define LOG_OFFSET(log, name)                    \
 780   if (p2i(name##_end()) - p2i(name##_begin())) \
 781     log->print(" " XSTR(name) "_offset='" INTX_FORMAT "'"    , \
 782                p2i(name##_begin()) - p2i(this))
 783 
 784 
 785 void nmethod::log_new_nmethod() const {
 786   if (LogCompilation && xtty != NULL) {
 787     ttyLocker ttyl;
 788     HandleMark hm;
 789     xtty->begin_elem("nmethod");
 790     log_identity(xtty);
 791     xtty->print(" entry='" INTPTR_FORMAT "' size='%d'", p2i(code_begin()), size());
 792     xtty->print(" address='" INTPTR_FORMAT "'", p2i(this));
 793 
 794     LOG_OFFSET(xtty, relocation);
 795     LOG_OFFSET(xtty, consts);
 796     LOG_OFFSET(xtty, insts);
 797     LOG_OFFSET(xtty, stub);
 798     LOG_OFFSET(xtty, scopes_data);
 799     LOG_OFFSET(xtty, scopes_pcs);
 800     LOG_OFFSET(xtty, dependencies);
 801     LOG_OFFSET(xtty, handler_table);
 802     LOG_OFFSET(xtty, nul_chk_table);
 803     LOG_OFFSET(xtty, oops);
 804     LOG_OFFSET(xtty, metadata);
 805 
 806     xtty->method(method());
 807     xtty->stamp();
 808     xtty->end_elem();
 809   }
 810 }
 811 
 812 #undef LOG_OFFSET
 813 
 814 
 815 // Print out more verbose output usually for a newly created nmethod.
 816 void nmethod::print_on(outputStream* st, const char* msg) const {
 817   if (st != NULL) {
 818     ttyLocker ttyl;
 819     if (WizardMode) {
 820       CompileTask::print(st, this, msg, /*short_form:*/ true);
 821       st->print_cr(" (" INTPTR_FORMAT ")", p2i(this));
 822     } else {
 823       CompileTask::print(st, this, msg, /*short_form:*/ false);
 824     }
 825   }
 826 }
 827 
 828 void nmethod::maybe_print_nmethod(DirectiveSet* directive) {
 829   bool printnmethods = directive->PrintAssemblyOption || directive->PrintNMethodsOption;
 830   if (printnmethods || PrintDebugInfo || PrintRelocations || PrintDependencies || PrintExceptionHandlers) {
 831     print_nmethod(printnmethods);
 832   }
 833 }
 834 
 835 void nmethod::print_nmethod(bool printmethod) {
 836   ttyLocker ttyl;  // keep the following output all in one block
 837   if (xtty != NULL) {
 838     xtty->begin_head("print_nmethod");
 839     xtty->stamp();
 840     xtty->end_head();
 841   }
 842   // print the header part first
 843   print();
 844   // then print the requested information
 845   if (printmethod) {
 846     print_code();
 847     print_pcs();
 848     if (oop_maps()) {
 849       oop_maps()->print();
 850     }
 851   }
 852   if (printmethod || PrintDebugInfo || CompilerOracle::has_option_string(_method, "PrintDebugInfo")) {
 853     print_scopes();
 854   }
 855   if (printmethod || PrintRelocations || CompilerOracle::has_option_string(_method, "PrintRelocations")) {
 856     print_relocations();
 857   }
 858   if (printmethod || PrintDependencies || CompilerOracle::has_option_string(_method, "PrintDependencies")) {
 859     print_dependencies();
 860   }
 861   if (printmethod || PrintExceptionHandlers) {
 862     print_handler_table();
 863     print_nul_chk_table();
 864   }
 865   if (printmethod) {
 866     print_recorded_oops();
 867     print_recorded_metadata();
 868   }
 869   if (xtty != NULL) {
 870     xtty->tail("print_nmethod");
 871   }
 872 }
 873 
 874 
 875 // Promote one word from an assembly-time handle to a live embedded oop.
 876 inline void nmethod::initialize_immediate_oop(oop* dest, jobject handle) {
 877   if (handle == NULL ||
 878       // As a special case, IC oops are initialized to 1 or -1.
 879       handle == (jobject) Universe::non_oop_word()) {
 880     (*dest) = (oop) handle;
 881   } else {
 882     (*dest) = JNIHandles::resolve_non_null(handle);
 883   }
 884 }
 885 
 886 
 887 // Have to have the same name because it's called by a template
 888 void nmethod::copy_values(GrowableArray<jobject>* array) {
 889   int length = array->length();
 890   assert((address)(oops_begin() + length) <= (address)oops_end(), "oops big enough");
 891   oop* dest = oops_begin();
 892   for (int index = 0 ; index < length; index++) {
 893     initialize_immediate_oop(&dest[index], array->at(index));
 894   }
 895 
 896   // Now we can fix up all the oops in the code.  We need to do this
 897   // in the code because the assembler uses jobjects as placeholders.
 898   // The code and relocations have already been initialized by the
 899   // CodeBlob constructor, so it is valid even at this early point to
 900   // iterate over relocations and patch the code.
 901   fix_oop_relocations(NULL, NULL, /*initialize_immediates=*/ true);
 902 }
 903 
 904 void nmethod::copy_values(GrowableArray<Metadata*>* array) {
 905   int length = array->length();
 906   assert((address)(metadata_begin() + length) <= (address)metadata_end(), "big enough");
 907   Metadata** dest = metadata_begin();
 908   for (int index = 0 ; index < length; index++) {
 909     dest[index] = array->at(index);
 910   }
 911 }
 912 
 913 void nmethod::fix_oop_relocations(address begin, address end, bool initialize_immediates) {
 914   // re-patch all oop-bearing instructions, just in case some oops moved
 915   RelocIterator iter(this, begin, end);
 916   while (iter.next()) {
 917     if (iter.type() == relocInfo::oop_type) {
 918       oop_Relocation* reloc = iter.oop_reloc();
 919       if (initialize_immediates && reloc->oop_is_immediate()) {
 920         oop* dest = reloc->oop_addr();
 921         initialize_immediate_oop(dest, (jobject) *dest);
 922       }
 923       // Refresh the oop-related bits of this instruction.
 924       reloc->fix_oop_relocation();
 925     } else if (iter.type() == relocInfo::metadata_type) {
 926       metadata_Relocation* reloc = iter.metadata_reloc();
 927       reloc->fix_metadata_relocation();
 928     }
 929   }
 930 }
 931 
 932 
 933 void nmethod::verify_clean_inline_caches() {
 934   assert_locked_or_safepoint(CompiledIC_lock);
 935 
 936   // If the method is not entrant or zombie then a JMP is plastered over the
 937   // first few bytes.  If an oop in the old code was there, that oop
 938   // should not get GC'd.  Skip the first few bytes of oops on
 939   // not-entrant methods.
 940   address low_boundary = verified_entry_point();
 941   if (!is_in_use()) {
 942     low_boundary += NativeJump::instruction_size;
 943     // %%% Note:  On SPARC we patch only a 4-byte trap, not a full NativeJump.
 944     // This means that the low_boundary is going to be a little too high.
 945     // This shouldn't matter, since oops of non-entrant methods are never used.
 946     // In fact, why are we bothering to look at oops in a non-entrant method??
 947   }
 948 
 949   ResourceMark rm;
 950   RelocIterator iter(this, low_boundary);
 951   while(iter.next()) {
 952     switch(iter.type()) {
 953       case relocInfo::virtual_call_type:
 954       case relocInfo::opt_virtual_call_type: {
 955         CompiledIC *ic = CompiledIC_at(&iter);
 956         // Ok, to lookup references to zombies here
 957         CodeBlob *cb = CodeCache::find_blob_unsafe(ic->ic_destination());

 958         nmethod* nm = cb->as_nmethod_or_null();
 959         if( nm != NULL ) {
 960           // Verify that inline caches pointing to both zombie and not_entrant methods are clean
 961           if (!nm->is_in_use() || (nm->method()->code() != nm)) {
 962             assert(ic->is_clean(), "IC should be clean");
 963           }
 964         }
 965         break;
 966       }
 967       case relocInfo::static_call_type: {
 968         CompiledStaticCall *csc = compiledStaticCall_at(iter.reloc());
 969         CodeBlob *cb = CodeCache::find_blob_unsafe(csc->destination());

 970         nmethod* nm = cb->as_nmethod_or_null();
 971         if( nm != NULL ) {
 972           // Verify that inline caches pointing to both zombie and not_entrant methods are clean
 973           if (!nm->is_in_use() || (nm->method()->code() != nm)) {
 974             assert(csc->is_clean(), "IC should be clean");
 975           }
 976         }
 977         break;
 978       }
 979       default:
 980         break;
 981     }
 982   }
 983 }
 984 
 985 // This is a private interface with the sweeper.
 986 void nmethod::mark_as_seen_on_stack() {
 987   assert(is_alive(), "Must be an alive method");
 988   // Set the traversal mark to ensure that the sweeper does 2
 989   // cleaning passes before moving to zombie.
 990   set_stack_traversal_mark(NMethodSweeper::traversal_count());
 991 }
 992 
 993 // Tell if a non-entrant method can be converted to a zombie (i.e.,
 994 // there are no activations on the stack, not in use by the VM,
 995 // and not in use by the ServiceThread)
 996 bool nmethod::can_convert_to_zombie() {
 997   assert(is_not_entrant(), "must be a non-entrant method");
 998 
 999   // Since the nmethod sweeper only does partial sweep the sweeper's traversal
1000   // count can be greater than the stack traversal count before it hits the
1001   // nmethod for the second time.
1002   return stack_traversal_mark()+1 < NMethodSweeper::traversal_count() &&
1003          !is_locked_by_vm();
1004 }
1005 
1006 void nmethod::inc_decompile_count() {
1007   if (!is_compiled_by_c2() && !is_compiled_by_jvmci()) return;
1008   // Could be gated by ProfileTraps, but do not bother...
1009   Method* m = method();
1010   if (m == NULL)  return;
1011   MethodData* mdo = m->method_data();
1012   if (mdo == NULL)  return;
1013   // There is a benign race here.  See comments in methodData.hpp.
1014   mdo->inc_decompile_count();
1015 }
1016 
1017 void nmethod::make_unloaded(BoolObjectClosure* is_alive, oop cause) {
1018 
1019   post_compiled_method_unload();
1020 
1021   // Since this nmethod is being unloaded, make sure that dependencies
1022   // recorded in instanceKlasses get flushed and pass non-NULL closure to
1023   // indicate that this work is being done during a GC.
1024   assert(Universe::heap()->is_gc_active(), "should only be called during gc");
1025   assert(is_alive != NULL, "Should be non-NULL");
1026   // A non-NULL is_alive closure indicates that this is being called during GC.
1027   flush_dependencies(is_alive);
1028 
1029   // Break cycle between nmethod & method
1030   LogTarget(Trace, class, unload) lt;
1031   if (lt.is_enabled()) {
1032     LogStream ls(lt);
1033     ls.print_cr("making nmethod " INTPTR_FORMAT
1034                   " unloadable, Method*(" INTPTR_FORMAT
1035                   "), cause(" INTPTR_FORMAT ")",
1036                   p2i(this), p2i(_method), p2i(cause));
1037   }
1038   // Unlink the osr method, so we do not look this up again
1039   if (is_osr_method()) {
1040     // Invalidate the osr nmethod only once
1041     if (is_in_use()) {
1042       invalidate_osr_method();
1043     }
1044 #ifdef ASSERT
1045     if (method() != NULL) {
1046       // Make sure osr nmethod is invalidated, i.e. not on the list
1047       bool found = method()->method_holder()->remove_osr_nmethod(this);
1048       assert(!found, "osr nmethod should have been invalidated");
1049     }
1050 #endif
1051   }
1052 
1053   // If _method is already NULL the Method* is about to be unloaded,
1054   // so we don't have to break the cycle. Note that it is possible to
1055   // have the Method* live here, in case we unload the nmethod because
1056   // it is pointing to some oop (other than the Method*) being unloaded.
1057   if (_method != NULL) {
1058     // OSR methods point to the Method*, but the Method* does not
1059     // point back!
1060     if (_method->code() == this) {
1061       _method->clear_code(); // Break a cycle
1062     }
1063     _method = NULL;            // Clear the method of this dead nmethod
1064   }
1065 
1066   // Make the class unloaded - i.e., change state and notify sweeper
1067   assert(SafepointSynchronize::is_at_safepoint(), "must be at safepoint");
1068   if (is_in_use()) {
1069     // Transitioning directly from live to unloaded -- so
1070     // we need to force a cache clean-up; remember this
1071     // for later on.
1072     CodeCache::set_needs_cache_clean(true);
1073   }
1074 
1075   // Unregister must be done before the state change
1076   Universe::heap()->unregister_nmethod(this);
1077 
1078   _state = unloaded;
1079 
1080   // Log the unloading.
1081   log_state_change();
1082 
1083 #if INCLUDE_JVMCI
1084   // The method can only be unloaded after the pointer to the installed code
1085   // Java wrapper is no longer alive. Here we need to clear out this weak
1086   // reference to the dead object.
1087   maybe_invalidate_installed_code();
1088 #endif
1089 
1090   // The Method* is gone at this point
1091   assert(_method == NULL, "Tautology");
1092 
1093   set_osr_link(NULL);
1094   NMethodSweeper::report_state_change(this);
1095 }
1096 
1097 void nmethod::invalidate_osr_method() {
1098   assert(_entry_bci != InvocationEntryBci, "wrong kind of nmethod");
1099   // Remove from list of active nmethods
1100   if (method() != NULL) {
1101     method()->method_holder()->remove_osr_nmethod(this);
1102   }
1103 }
1104 
1105 void nmethod::log_state_change() const {
1106   if (LogCompilation) {
1107     if (xtty != NULL) {
1108       ttyLocker ttyl;  // keep the following output all in one block
1109       if (_state == unloaded) {
1110         xtty->begin_elem("make_unloaded thread='" UINTX_FORMAT "'",
1111                          os::current_thread_id());
1112       } else {
1113         xtty->begin_elem("make_not_entrant thread='" UINTX_FORMAT "'%s",
1114                          os::current_thread_id(),
1115                          (_state == zombie ? " zombie='1'" : ""));
1116       }
1117       log_identity(xtty);
1118       xtty->stamp();
1119       xtty->end_elem();
1120     }
1121   }
1122 
1123   const char *state_msg = _state == zombie ? "made zombie" : "made not entrant";
1124   CompileTask::print_ul(this, state_msg);
1125   if (PrintCompilation && _state != unloaded) {
1126     print_on(tty, state_msg);
1127   }
1128 }
1129 
1130 /**
1131  * Common functionality for both make_not_entrant and make_zombie
1132  */
1133 bool nmethod::make_not_entrant_or_zombie(int state) {
1134   assert(state == zombie || state == not_entrant, "must be zombie or not_entrant");
1135   assert(!is_zombie(), "should not already be a zombie");
1136 
1137   if (_state == state) {
1138     // Avoid taking the lock if already in required state.
1139     // This is safe from races because the state is an end-state,
1140     // which the nmethod cannot back out of once entered.
1141     // No need for fencing either.
1142     return false;
1143   }
1144 
1145   // Make sure neither the nmethod nor the method is flushed in case of a safepoint in code below.
1146   nmethodLocker nml(this);
1147   methodHandle the_method(method());
1148   NoSafepointVerifier nsv;
1149 
1150   // during patching, depending on the nmethod state we must notify the GC that
1151   // code has been unloaded, unregistering it. We cannot do this right while
1152   // holding the Patching_lock because we need to use the CodeCache_lock. This
1153   // would be prone to deadlocks.
1154   // This flag is used to remember whether we need to later lock and unregister.
1155   bool nmethod_needs_unregister = false;
1156 
1157   {
1158     // invalidate osr nmethod before acquiring the patching lock since
1159     // they both acquire leaf locks and we don't want a deadlock.
1160     // This logic is equivalent to the logic below for patching the
1161     // verified entry point of regular methods. We check that the
1162     // nmethod is in use to ensure that it is invalidated only once.
1163     if (is_osr_method() && is_in_use()) {
1164       // this effectively makes the osr nmethod not entrant
1165       invalidate_osr_method();
1166     }
1167 
1168     // Enter critical section.  Does not block for safepoint.
1169     MutexLockerEx pl(Patching_lock, Mutex::_no_safepoint_check_flag);
1170 
1171     if (_state == state) {
1172       // another thread already performed this transition so nothing
1173       // to do, but return false to indicate this.
1174       return false;
1175     }
1176 
1177     // The caller can be calling the method statically or through an inline
1178     // cache call.
1179     if (!is_osr_method() && !is_not_entrant()) {
1180       NativeJump::patch_verified_entry(entry_point(), verified_entry_point(),
1181                   SharedRuntime::get_handle_wrong_method_stub());
1182     }
1183 
1184     if (is_in_use() && update_recompile_counts()) {
1185       // It's a true state change, so mark the method as decompiled.
1186       // Do it only for transition from alive.
1187       inc_decompile_count();
1188     }
1189 
1190     // If the state is becoming a zombie, signal to unregister the nmethod with
1191     // the heap.
1192     // This nmethod may have already been unloaded during a full GC.
1193     if ((state == zombie) && !is_unloaded()) {
1194       nmethod_needs_unregister = true;
1195     }
1196 
1197     // Must happen before state change. Otherwise we have a race condition in
1198     // nmethod::can_not_entrant_be_converted(). I.e., a method can immediately
1199     // transition its state from 'not_entrant' to 'zombie' without having to wait
1200     // for stack scanning.
1201     if (state == not_entrant) {
1202       mark_as_seen_on_stack();
1203       OrderAccess::storestore(); // _stack_traversal_mark and _state
1204     }
1205 
1206     // Change state
1207     _state = state;
1208 
1209     // Log the transition once
1210     log_state_change();
1211 
1212     // Invalidate while holding the patching lock
1213     JVMCI_ONLY(maybe_invalidate_installed_code());
1214 
1215     // Remove nmethod from method.
1216     // We need to check if both the _code and _from_compiled_code_entry_point
1217     // refer to this nmethod because there is a race in setting these two fields
1218     // in Method* as seen in bugid 4947125.
1219     // If the vep() points to the zombie nmethod, the memory for the nmethod
1220     // could be flushed and the compiler and vtable stubs could still call
1221     // through it.
1222     if (method() != NULL && (method()->code() == this ||
1223                              method()->from_compiled_entry() == verified_entry_point())) {
1224       HandleMark hm;
1225       method()->clear_code(false /* already owns Patching_lock */);
1226     }
1227   } // leave critical region under Patching_lock
1228 
1229 #ifdef ASSERT
1230   if (is_osr_method() && method() != NULL) {
1231     // Make sure osr nmethod is invalidated, i.e. not on the list
1232     bool found = method()->method_holder()->remove_osr_nmethod(this);
1233     assert(!found, "osr nmethod should have been invalidated");
1234   }
1235 #endif
1236 
1237   // When the nmethod becomes zombie it is no longer alive so the
1238   // dependencies must be flushed.  nmethods in the not_entrant
1239   // state will be flushed later when the transition to zombie
1240   // happens or they get unloaded.
1241   if (state == zombie) {
1242     {
1243       // Flushing dependencies must be done before any possible
1244       // safepoint can sneak in, otherwise the oops used by the
1245       // dependency logic could have become stale.
1246       MutexLockerEx mu(CodeCache_lock, Mutex::_no_safepoint_check_flag);
1247       if (nmethod_needs_unregister) {
1248         Universe::heap()->unregister_nmethod(this);
1249       }
1250       flush_dependencies(NULL);
1251     }
1252 
1253     // zombie only - if a JVMTI agent has enabled the CompiledMethodUnload
1254     // event and it hasn't already been reported for this nmethod then
1255     // report it now. The event may have been reported earlier if the GC
1256     // marked it for unloading). JvmtiDeferredEventQueue support means
1257     // we no longer go to a safepoint here.
1258     post_compiled_method_unload();
1259 
1260 #ifdef ASSERT
1261     // It's no longer safe to access the oops section since zombie
1262     // nmethods aren't scanned for GC.
1263     _oops_are_stale = true;
1264 #endif
1265      // the Method may be reclaimed by class unloading now that the
1266      // nmethod is in zombie state
1267     set_method(NULL);
1268   } else {
1269     assert(state == not_entrant, "other cases may need to be handled differently");
1270   }
1271 
1272   if (TraceCreateZombies) {
1273     ResourceMark m;
1274     tty->print_cr("nmethod <" INTPTR_FORMAT "> %s code made %s", p2i(this), this->method() ? this->method()->name_and_sig_as_C_string() : "null", (state == not_entrant) ? "not entrant" : "zombie");
1275   }
1276 
1277   NMethodSweeper::report_state_change(this);
1278   return true;
1279 }
1280 
1281 void nmethod::flush() {
1282   // Note that there are no valid oops in the nmethod anymore.
1283   assert(!is_osr_method() || is_unloaded() || is_zombie(),
1284          "osr nmethod must be unloaded or zombie before flushing");
1285   assert(is_zombie() || is_osr_method(), "must be a zombie method");
1286   assert (!is_locked_by_vm(), "locked methods shouldn't be flushed");
1287   assert_locked_or_safepoint(CodeCache_lock);
1288 
1289   // completely deallocate this method
1290   Events::log(JavaThread::current(), "flushing nmethod " INTPTR_FORMAT, p2i(this));
1291   if (PrintMethodFlushing) {
1292     tty->print_cr("*flushing %s nmethod %3d/" INTPTR_FORMAT ". Live blobs:" UINT32_FORMAT
1293                   "/Free CodeCache:" SIZE_FORMAT "Kb",
1294                   is_osr_method() ? "osr" : "",_compile_id, p2i(this), CodeCache::blob_count(),
1295                   CodeCache::unallocated_capacity(CodeCache::get_code_blob_type(this))/1024);
1296   }
1297 
1298   // We need to deallocate any ExceptionCache data.
1299   // Note that we do not need to grab the nmethod lock for this, it
1300   // better be thread safe if we're disposing of it!
1301   ExceptionCache* ec = exception_cache();
1302   set_exception_cache(NULL);
1303   while(ec != NULL) {
1304     ExceptionCache* next = ec->next();
1305     delete ec;
1306     ec = next;
1307   }
1308 
1309   if (on_scavenge_root_list()) {
1310     CodeCache::drop_scavenge_root_nmethod(this);
1311   }
1312 
1313 #if INCLUDE_JVMCI
1314   assert(_jvmci_installed_code == NULL, "should have been nulled out when transitioned to zombie");
1315   assert(_speculation_log == NULL, "should have been nulled out when transitioned to zombie");
1316 #endif
1317 
1318   CodeBlob::flush();
1319   CodeCache::free(this);
1320 }
1321 
1322 //
1323 // Notify all classes this nmethod is dependent on that it is no
1324 // longer dependent. This should only be called in two situations.
1325 // First, when a nmethod transitions to a zombie all dependents need
1326 // to be clear.  Since zombification happens at a safepoint there's no
1327 // synchronization issues.  The second place is a little more tricky.
1328 // During phase 1 of mark sweep class unloading may happen and as a
1329 // result some nmethods may get unloaded.  In this case the flushing
1330 // of dependencies must happen during phase 1 since after GC any
1331 // dependencies in the unloaded nmethod won't be updated, so
1332 // traversing the dependency information in unsafe.  In that case this
1333 // function is called with a non-NULL argument and this function only
1334 // notifies instanceKlasses that are reachable
1335 
1336 void nmethod::flush_dependencies(BoolObjectClosure* is_alive) {
1337   assert_locked_or_safepoint(CodeCache_lock);
1338   assert(Universe::heap()->is_gc_active() == (is_alive != NULL),
1339   "is_alive is non-NULL if and only if we are called during GC");
1340   if (!has_flushed_dependencies()) {
1341     set_has_flushed_dependencies();
1342     for (Dependencies::DepStream deps(this); deps.next(); ) {
1343       if (deps.type() == Dependencies::call_site_target_value) {
1344         // CallSite dependencies are managed on per-CallSite instance basis.
1345         oop call_site = deps.argument_oop(0);
1346         MethodHandles::remove_dependent_nmethod(call_site, this);
1347       } else {
1348         Klass* klass = deps.context_type();
1349         if (klass == NULL) {
1350           continue;  // ignore things like evol_method
1351         }
1352         // During GC the is_alive closure is non-NULL, and is used to
1353         // determine liveness of dependees that need to be updated.
1354         if (is_alive == NULL || klass->is_loader_alive(is_alive)) {
1355           // The GC defers deletion of this entry, since there might be multiple threads
1356           // iterating over the _dependencies graph. Other call paths are single-threaded
1357           // and may delete it immediately.
1358           bool delete_immediately = is_alive == NULL;
1359           InstanceKlass::cast(klass)->remove_dependent_nmethod(this, delete_immediately);
1360         }
1361       }
1362     }
1363   }
1364 }
1365 
1366 
1367 // If this oop is not live, the nmethod can be unloaded.
1368 bool nmethod::can_unload(BoolObjectClosure* is_alive, oop* root, bool unloading_occurred) {
1369   assert(root != NULL, "just checking");
1370   oop obj = *root;
1371   if (obj == NULL || is_alive->do_object_b(obj)) {
1372       return false;
1373   }
1374 
1375   // If ScavengeRootsInCode is true, an nmethod might be unloaded
1376   // simply because one of its constant oops has gone dead.
1377   // No actual classes need to be unloaded in order for this to occur.
1378   assert(unloading_occurred || ScavengeRootsInCode, "Inconsistency in unloading");
1379   make_unloaded(is_alive, obj);
1380   return true;
1381 }
1382 
1383 // ------------------------------------------------------------------
1384 // post_compiled_method_load_event
1385 // new method for install_code() path
1386 // Transfer information from compilation to jvmti
1387 void nmethod::post_compiled_method_load_event() {
1388 
1389   Method* moop = method();
1390   HOTSPOT_COMPILED_METHOD_LOAD(
1391       (char *) moop->klass_name()->bytes(),
1392       moop->klass_name()->utf8_length(),
1393       (char *) moop->name()->bytes(),
1394       moop->name()->utf8_length(),
1395       (char *) moop->signature()->bytes(),
1396       moop->signature()->utf8_length(),
1397       insts_begin(), insts_size());
1398 
1399   if (JvmtiExport::should_post_compiled_method_load() ||
1400       JvmtiExport::should_post_compiled_method_unload()) {
1401     get_and_cache_jmethod_id();
1402   }
1403 
1404   if (JvmtiExport::should_post_compiled_method_load()) {
1405     // Let the Service thread (which is a real Java thread) post the event
1406     MutexLockerEx ml(Service_lock, Mutex::_no_safepoint_check_flag);
1407     JvmtiDeferredEventQueue::enqueue(
1408       JvmtiDeferredEvent::compiled_method_load_event(this));
1409   }
1410 }
1411 
1412 jmethodID nmethod::get_and_cache_jmethod_id() {
1413   if (_jmethod_id == NULL) {
1414     // Cache the jmethod_id since it can no longer be looked up once the
1415     // method itself has been marked for unloading.
1416     _jmethod_id = method()->jmethod_id();
1417   }
1418   return _jmethod_id;
1419 }
1420 
1421 void nmethod::post_compiled_method_unload() {
1422   if (unload_reported()) {
1423     // During unloading we transition to unloaded and then to zombie
1424     // and the unloading is reported during the first transition.
1425     return;
1426   }
1427 
1428   assert(_method != NULL && !is_unloaded(), "just checking");
1429   DTRACE_METHOD_UNLOAD_PROBE(method());
1430 
1431   // If a JVMTI agent has enabled the CompiledMethodUnload event then
1432   // post the event. Sometime later this nmethod will be made a zombie
1433   // by the sweeper but the Method* will not be valid at that point.
1434   // If the _jmethod_id is null then no load event was ever requested
1435   // so don't bother posting the unload.  The main reason for this is
1436   // that the jmethodID is a weak reference to the Method* so if
1437   // it's being unloaded there's no way to look it up since the weak
1438   // ref will have been cleared.
1439   if (_jmethod_id != NULL && JvmtiExport::should_post_compiled_method_unload()) {
1440     assert(!unload_reported(), "already unloaded");
1441     JvmtiDeferredEvent event =
1442       JvmtiDeferredEvent::compiled_method_unload_event(this,
1443           _jmethod_id, insts_begin());
1444     MutexLockerEx ml(Service_lock, Mutex::_no_safepoint_check_flag);
1445     JvmtiDeferredEventQueue::enqueue(event);
1446   }
1447 
1448   // The JVMTI CompiledMethodUnload event can be enabled or disabled at
1449   // any time. As the nmethod is being unloaded now we mark it has
1450   // having the unload event reported - this will ensure that we don't
1451   // attempt to report the event in the unlikely scenario where the
1452   // event is enabled at the time the nmethod is made a zombie.
1453   set_unload_reported();
1454 }
1455 
1456 bool nmethod::unload_if_dead_at(RelocIterator* iter_at_oop, BoolObjectClosure *is_alive, bool unloading_occurred) {
1457   assert(iter_at_oop->type() == relocInfo::oop_type, "Wrong relocation type");
1458 
1459   oop_Relocation* r = iter_at_oop->oop_reloc();
1460   // Traverse those oops directly embedded in the code.
1461   // Other oops (oop_index>0) are seen as part of scopes_oops.
1462   assert(1 == (r->oop_is_immediate()) +
1463          (r->oop_addr() >= oops_begin() && r->oop_addr() < oops_end()),
1464          "oop must be found in exactly one place");
1465   if (r->oop_is_immediate() && r->oop_value() != NULL) {
1466     // Unload this nmethod if the oop is dead.
1467     if (can_unload(is_alive, r->oop_addr(), unloading_occurred)) {
1468       return true;;
1469     }
1470   }
1471 
1472   return false;
1473 }
1474 
1475 bool nmethod::do_unloading_scopes(BoolObjectClosure* is_alive, bool unloading_occurred) {
1476   // Scopes
1477   for (oop* p = oops_begin(); p < oops_end(); p++) {
1478     if (*p == Universe::non_oop_word())  continue;  // skip non-oops
1479     if (can_unload(is_alive, p, unloading_occurred)) {
1480       return true;
1481     }
1482   }
1483   return false;
1484 }
1485 
1486 bool nmethod::do_unloading_oops(address low_boundary, BoolObjectClosure* is_alive, bool unloading_occurred) {
1487   // Compiled code
1488 
1489   // Prevent extra code cache walk for platforms that don't have immediate oops.
1490   if (relocInfo::mustIterateImmediateOopsInCode()) {
1491     RelocIterator iter(this, low_boundary);
1492     while (iter.next()) {
1493       if (iter.type() == relocInfo::oop_type) {
1494         if (unload_if_dead_at(&iter, is_alive, unloading_occurred)) {
1495           return true;
1496         }
1497       }
1498     }
1499   }
1500 
1501   return do_unloading_scopes(is_alive, unloading_occurred);
1502 }
1503 
1504 #if INCLUDE_JVMCI
1505 bool nmethod::do_unloading_jvmci(BoolObjectClosure* is_alive, bool unloading_occurred) {
1506   if (_jvmci_installed_code != NULL) {
1507     if (JNIHandles::is_global_weak_cleared(_jvmci_installed_code)) {
1508       if (_jvmci_installed_code_triggers_unloading) {
1509         // jweak reference processing has already cleared the referent
1510         make_unloaded(is_alive, NULL);
1511         return true;
1512       } else {
1513         clear_jvmci_installed_code();
1514       }
1515     }
1516   }
1517   return false;
1518 }
1519 #endif
1520 
1521 // Iterate over metadata calling this function.   Used by RedefineClasses
1522 void nmethod::metadata_do(void f(Metadata*)) {
1523   address low_boundary = verified_entry_point();
1524   if (is_not_entrant()) {
1525     low_boundary += NativeJump::instruction_size;
1526     // %%% Note:  On SPARC we patch only a 4-byte trap, not a full NativeJump.
1527     // (See comment above.)
1528   }
1529   {
1530     // Visit all immediate references that are embedded in the instruction stream.
1531     RelocIterator iter(this, low_boundary);
1532     while (iter.next()) {
1533       if (iter.type() == relocInfo::metadata_type ) {
1534         metadata_Relocation* r = iter.metadata_reloc();
1535         // In this metadata, we must only follow those metadatas directly embedded in
1536         // the code.  Other metadatas (oop_index>0) are seen as part of
1537         // the metadata section below.
1538         assert(1 == (r->metadata_is_immediate()) +
1539                (r->metadata_addr() >= metadata_begin() && r->metadata_addr() < metadata_end()),
1540                "metadata must be found in exactly one place");
1541         if (r->metadata_is_immediate() && r->metadata_value() != NULL) {
1542           Metadata* md = r->metadata_value();
1543           if (md != _method) f(md);
1544         }
1545       } else if (iter.type() == relocInfo::virtual_call_type) {
1546         // Check compiledIC holders associated with this nmethod
1547         CompiledIC *ic = CompiledIC_at(&iter);
1548         if (ic->is_icholder_call()) {
1549           CompiledICHolder* cichk = ic->cached_icholder();
1550           f(cichk->holder_method());
1551           f(cichk->holder_klass());
1552         } else {
1553           Metadata* ic_oop = ic->cached_metadata();
1554           if (ic_oop != NULL) {
1555             f(ic_oop);
1556           }
1557         }
1558       }
1559     }
1560   }
1561 
1562   // Visit the metadata section
1563   for (Metadata** p = metadata_begin(); p < metadata_end(); p++) {
1564     if (*p == Universe::non_oop_word() || *p == NULL)  continue;  // skip non-oops
1565     Metadata* md = *p;
1566     f(md);
1567   }
1568 
1569   // Visit metadata not embedded in the other places.
1570   if (_method != NULL) f(_method);
1571 }
1572 
1573 void nmethod::oops_do(OopClosure* f, bool allow_zombie) {
1574   // make sure the oops ready to receive visitors
1575   assert(allow_zombie || !is_zombie(), "should not call follow on zombie nmethod");
1576   assert(!is_unloaded(), "should not call follow on unloaded nmethod");
1577 
1578   // If the method is not entrant or zombie then a JMP is plastered over the
1579   // first few bytes.  If an oop in the old code was there, that oop
1580   // should not get GC'd.  Skip the first few bytes of oops on
1581   // not-entrant methods.
1582   address low_boundary = verified_entry_point();
1583   if (is_not_entrant()) {
1584     low_boundary += NativeJump::instruction_size;
1585     // %%% Note:  On SPARC we patch only a 4-byte trap, not a full NativeJump.
1586     // (See comment above.)
1587   }
1588 
1589   // Prevent extra code cache walk for platforms that don't have immediate oops.
1590   if (relocInfo::mustIterateImmediateOopsInCode()) {
1591     RelocIterator iter(this, low_boundary);
1592 
1593     while (iter.next()) {
1594       if (iter.type() == relocInfo::oop_type ) {
1595         oop_Relocation* r = iter.oop_reloc();
1596         // In this loop, we must only follow those oops directly embedded in
1597         // the code.  Other oops (oop_index>0) are seen as part of scopes_oops.
1598         assert(1 == (r->oop_is_immediate()) +
1599                (r->oop_addr() >= oops_begin() && r->oop_addr() < oops_end()),
1600                "oop must be found in exactly one place");
1601         if (r->oop_is_immediate() && r->oop_value() != NULL) {
1602           f->do_oop(r->oop_addr());
1603         }
1604       }
1605     }
1606   }
1607 
1608   // Scopes
1609   // This includes oop constants not inlined in the code stream.
1610   for (oop* p = oops_begin(); p < oops_end(); p++) {
1611     if (*p == Universe::non_oop_word())  continue;  // skip non-oops
1612     f->do_oop(p);
1613   }
1614 }
1615 
1616 #define NMETHOD_SENTINEL ((nmethod*)badAddress)
1617 
1618 nmethod* volatile nmethod::_oops_do_mark_nmethods;
1619 
1620 // An nmethod is "marked" if its _mark_link is set non-null.
1621 // Even if it is the end of the linked list, it will have a non-null link value,
1622 // as long as it is on the list.
1623 // This code must be MP safe, because it is used from parallel GC passes.
1624 bool nmethod::test_set_oops_do_mark() {
1625   assert(nmethod::oops_do_marking_is_active(), "oops_do_marking_prologue must be called");
1626   if (_oops_do_mark_link == NULL) {
1627     // Claim this nmethod for this thread to mark.
1628     if (Atomic::replace_if_null(NMETHOD_SENTINEL, &_oops_do_mark_link)) {
1629       // Atomically append this nmethod (now claimed) to the head of the list:
1630       nmethod* observed_mark_nmethods = _oops_do_mark_nmethods;
1631       for (;;) {
1632         nmethod* required_mark_nmethods = observed_mark_nmethods;
1633         _oops_do_mark_link = required_mark_nmethods;
1634         observed_mark_nmethods =
1635           Atomic::cmpxchg(this, &_oops_do_mark_nmethods, required_mark_nmethods);
1636         if (observed_mark_nmethods == required_mark_nmethods)
1637           break;
1638       }
1639       // Mark was clear when we first saw this guy.
1640       if (TraceScavenge) { print_on(tty, "oops_do, mark"); }
1641       return false;
1642     }
1643   }
1644   // On fall through, another racing thread marked this nmethod before we did.
1645   return true;
1646 }
1647 
1648 void nmethod::oops_do_marking_prologue() {
1649   if (TraceScavenge) { tty->print_cr("[oops_do_marking_prologue"); }
1650   assert(_oops_do_mark_nmethods == NULL, "must not call oops_do_marking_prologue twice in a row");
1651   // We use cmpxchg instead of regular assignment here because the user
1652   // may fork a bunch of threads, and we need them all to see the same state.
1653   nmethod* observed = Atomic::cmpxchg(NMETHOD_SENTINEL, &_oops_do_mark_nmethods, (nmethod*)NULL);
1654   guarantee(observed == NULL, "no races in this sequential code");
1655 }
1656 
1657 void nmethod::oops_do_marking_epilogue() {
1658   assert(_oops_do_mark_nmethods != NULL, "must not call oops_do_marking_epilogue twice in a row");
1659   nmethod* cur = _oops_do_mark_nmethods;
1660   while (cur != NMETHOD_SENTINEL) {
1661     assert(cur != NULL, "not NULL-terminated");
1662     nmethod* next = cur->_oops_do_mark_link;
1663     cur->_oops_do_mark_link = NULL;
1664     DEBUG_ONLY(cur->verify_oop_relocations());
1665     NOT_PRODUCT(if (TraceScavenge)  cur->print_on(tty, "oops_do, unmark"));
1666     cur = next;
1667   }
1668   nmethod* required = _oops_do_mark_nmethods;
1669   nmethod* observed = Atomic::cmpxchg((nmethod*)NULL, &_oops_do_mark_nmethods, required);
1670   guarantee(observed == required, "no races in this sequential code");
1671   if (TraceScavenge) { tty->print_cr("oops_do_marking_epilogue]"); }
1672 }
1673 
1674 class DetectScavengeRoot: public OopClosure {
1675   bool     _detected_scavenge_root;
1676 public:
1677   DetectScavengeRoot() : _detected_scavenge_root(false)
1678   { NOT_PRODUCT(_print_nm = NULL); }
1679   bool detected_scavenge_root() { return _detected_scavenge_root; }
1680   virtual void do_oop(oop* p) {
1681     if ((*p) != NULL && (*p)->is_scavengable()) {
1682       NOT_PRODUCT(maybe_print(p));
1683       _detected_scavenge_root = true;
1684     }
1685   }
1686   virtual void do_oop(narrowOop* p) { ShouldNotReachHere(); }
1687 
1688 #ifndef PRODUCT
1689   nmethod* _print_nm;
1690   void maybe_print(oop* p) {
1691     if (_print_nm == NULL)  return;
1692     if (!_detected_scavenge_root)  _print_nm->print_on(tty, "new scavenge root");
1693     tty->print_cr("" PTR_FORMAT "[offset=%d] detected scavengable oop " PTR_FORMAT " (found at " PTR_FORMAT ")",
1694                   p2i(_print_nm), (int)((intptr_t)p - (intptr_t)_print_nm),
1695                   p2i(*p), p2i(p));
1696     (*p)->print();
1697   }
1698 #endif //PRODUCT
1699 };
1700 
1701 bool nmethod::detect_scavenge_root_oops() {
1702   DetectScavengeRoot detect_scavenge_root;
1703   NOT_PRODUCT(if (TraceScavenge)  detect_scavenge_root._print_nm = this);
1704   oops_do(&detect_scavenge_root);
1705   return detect_scavenge_root.detected_scavenge_root();
1706 }
1707 
1708 inline bool includes(void* p, void* from, void* to) {
1709   return from <= p && p < to;
1710 }
1711 
1712 
1713 void nmethod::copy_scopes_pcs(PcDesc* pcs, int count) {
1714   assert(count >= 2, "must be sentinel values, at least");
1715 
1716 #ifdef ASSERT
1717   // must be sorted and unique; we do a binary search in find_pc_desc()
1718   int prev_offset = pcs[0].pc_offset();
1719   assert(prev_offset == PcDesc::lower_offset_limit,
1720          "must start with a sentinel");
1721   for (int i = 1; i < count; i++) {
1722     int this_offset = pcs[i].pc_offset();
1723     assert(this_offset > prev_offset, "offsets must be sorted");
1724     prev_offset = this_offset;
1725   }
1726   assert(prev_offset == PcDesc::upper_offset_limit,
1727          "must end with a sentinel");
1728 #endif //ASSERT
1729 
1730   // Search for MethodHandle invokes and tag the nmethod.
1731   for (int i = 0; i < count; i++) {
1732     if (pcs[i].is_method_handle_invoke()) {
1733       set_has_method_handle_invokes(true);
1734       break;
1735     }
1736   }
1737   assert(has_method_handle_invokes() == (_deopt_mh_handler_begin != NULL), "must have deopt mh handler");
1738 
1739   int size = count * sizeof(PcDesc);
1740   assert(scopes_pcs_size() >= size, "oob");
1741   memcpy(scopes_pcs_begin(), pcs, size);
1742 
1743   // Adjust the final sentinel downward.
1744   PcDesc* last_pc = &scopes_pcs_begin()[count-1];
1745   assert(last_pc->pc_offset() == PcDesc::upper_offset_limit, "sanity");
1746   last_pc->set_pc_offset(content_size() + 1);
1747   for (; last_pc + 1 < scopes_pcs_end(); last_pc += 1) {
1748     // Fill any rounding gaps with copies of the last record.
1749     last_pc[1] = last_pc[0];
1750   }
1751   // The following assert could fail if sizeof(PcDesc) is not
1752   // an integral multiple of oopSize (the rounding term).
1753   // If it fails, change the logic to always allocate a multiple
1754   // of sizeof(PcDesc), and fill unused words with copies of *last_pc.
1755   assert(last_pc + 1 == scopes_pcs_end(), "must match exactly");
1756 }
1757 
1758 void nmethod::copy_scopes_data(u_char* buffer, int size) {
1759   assert(scopes_data_size() >= size, "oob");
1760   memcpy(scopes_data_begin(), buffer, size);
1761 }
1762 
1763 #ifdef ASSERT
1764 static PcDesc* linear_search(const PcDescSearch& search, int pc_offset, bool approximate) {
1765   PcDesc* lower = search.scopes_pcs_begin();
1766   PcDesc* upper = search.scopes_pcs_end();
1767   lower += 1; // exclude initial sentinel
1768   PcDesc* res = NULL;
1769   for (PcDesc* p = lower; p < upper; p++) {
1770     NOT_PRODUCT(--pc_nmethod_stats.pc_desc_tests);  // don't count this call to match_desc
1771     if (match_desc(p, pc_offset, approximate)) {
1772       if (res == NULL)
1773         res = p;
1774       else
1775         res = (PcDesc*) badAddress;
1776     }
1777   }
1778   return res;
1779 }
1780 #endif
1781 
1782 
1783 // Finds a PcDesc with real-pc equal to "pc"
1784 PcDesc* PcDescContainer::find_pc_desc_internal(address pc, bool approximate, const PcDescSearch& search) {
1785   address base_address = search.code_begin();
1786   if ((pc < base_address) ||
1787       (pc - base_address) >= (ptrdiff_t) PcDesc::upper_offset_limit) {
1788     return NULL;  // PC is wildly out of range
1789   }
1790   int pc_offset = (int) (pc - base_address);
1791 
1792   // Check the PcDesc cache if it contains the desired PcDesc
1793   // (This as an almost 100% hit rate.)
1794   PcDesc* res = _pc_desc_cache.find_pc_desc(pc_offset, approximate);
1795   if (res != NULL) {
1796     assert(res == linear_search(search, pc_offset, approximate), "cache ok");
1797     return res;
1798   }
1799 
1800   // Fallback algorithm: quasi-linear search for the PcDesc
1801   // Find the last pc_offset less than the given offset.
1802   // The successor must be the required match, if there is a match at all.
1803   // (Use a fixed radix to avoid expensive affine pointer arithmetic.)
1804   PcDesc* lower = search.scopes_pcs_begin();
1805   PcDesc* upper = search.scopes_pcs_end();
1806   upper -= 1; // exclude final sentinel
1807   if (lower >= upper)  return NULL;  // native method; no PcDescs at all
1808 
1809 #define assert_LU_OK \
1810   /* invariant on lower..upper during the following search: */ \
1811   assert(lower->pc_offset() <  pc_offset, "sanity"); \
1812   assert(upper->pc_offset() >= pc_offset, "sanity")
1813   assert_LU_OK;
1814 
1815   // Use the last successful return as a split point.
1816   PcDesc* mid = _pc_desc_cache.last_pc_desc();
1817   NOT_PRODUCT(++pc_nmethod_stats.pc_desc_searches);
1818   if (mid->pc_offset() < pc_offset) {
1819     lower = mid;
1820   } else {
1821     upper = mid;
1822   }
1823 
1824   // Take giant steps at first (4096, then 256, then 16, then 1)
1825   const int LOG2_RADIX = 4 /*smaller steps in debug mode:*/ debug_only(-1);
1826   const int RADIX = (1 << LOG2_RADIX);
1827   for (int step = (1 << (LOG2_RADIX*3)); step > 1; step >>= LOG2_RADIX) {
1828     while ((mid = lower + step) < upper) {
1829       assert_LU_OK;
1830       NOT_PRODUCT(++pc_nmethod_stats.pc_desc_searches);
1831       if (mid->pc_offset() < pc_offset) {
1832         lower = mid;
1833       } else {
1834         upper = mid;
1835         break;
1836       }
1837     }
1838     assert_LU_OK;
1839   }
1840 
1841   // Sneak up on the value with a linear search of length ~16.
1842   while (true) {
1843     assert_LU_OK;
1844     mid = lower + 1;
1845     NOT_PRODUCT(++pc_nmethod_stats.pc_desc_searches);
1846     if (mid->pc_offset() < pc_offset) {
1847       lower = mid;
1848     } else {
1849       upper = mid;
1850       break;
1851     }
1852   }
1853 #undef assert_LU_OK
1854 
1855   if (match_desc(upper, pc_offset, approximate)) {
1856     assert(upper == linear_search(search, pc_offset, approximate), "search ok");
1857     _pc_desc_cache.add_pc_desc(upper);
1858     return upper;
1859   } else {
1860     assert(NULL == linear_search(search, pc_offset, approximate), "search ok");
1861     return NULL;
1862   }
1863 }
1864 
1865 
1866 void nmethod::check_all_dependencies(DepChange& changes) {
1867   // Checked dependencies are allocated into this ResourceMark
1868   ResourceMark rm;
1869 
1870   // Turn off dependency tracing while actually testing dependencies.
1871   NOT_PRODUCT( FlagSetting fs(TraceDependencies, false) );
1872 
1873   typedef ResourceHashtable<DependencySignature, int, &DependencySignature::hash,
1874                             &DependencySignature::equals, 11027> DepTable;
1875 
1876   DepTable* table = new DepTable();
1877 
1878   // Iterate over live nmethods and check dependencies of all nmethods that are not
1879   // marked for deoptimization. A particular dependency is only checked once.
1880   NMethodIterator iter;
1881   while(iter.next()) {
1882     nmethod* nm = iter.method();
1883     // Only notify for live nmethods
1884     if (nm->is_alive() && !nm->is_marked_for_deoptimization()) {
1885       for (Dependencies::DepStream deps(nm); deps.next(); ) {
1886         // Construct abstraction of a dependency.
1887         DependencySignature* current_sig = new DependencySignature(deps);
1888 
1889         // Determine if dependency is already checked. table->put(...) returns
1890         // 'true' if the dependency is added (i.e., was not in the hashtable).
1891         if (table->put(*current_sig, 1)) {
1892           if (deps.check_dependency() != NULL) {
1893             // Dependency checking failed. Print out information about the failed
1894             // dependency and finally fail with an assert. We can fail here, since
1895             // dependency checking is never done in a product build.
1896             tty->print_cr("Failed dependency:");
1897             changes.print();
1898             nm->print();
1899             nm->print_dependencies();
1900             assert(false, "Should have been marked for deoptimization");
1901           }
1902         }
1903       }
1904     }
1905   }
1906 }
1907 
1908 bool nmethod::check_dependency_on(DepChange& changes) {
1909   // What has happened:
1910   // 1) a new class dependee has been added
1911   // 2) dependee and all its super classes have been marked
1912   bool found_check = false;  // set true if we are upset
1913   for (Dependencies::DepStream deps(this); deps.next(); ) {
1914     // Evaluate only relevant dependencies.
1915     if (deps.spot_check_dependency_at(changes) != NULL) {
1916       found_check = true;
1917       NOT_DEBUG(break);
1918     }
1919   }
1920   return found_check;
1921 }
1922 
1923 bool nmethod::is_evol_dependent_on(Klass* dependee) {
1924   InstanceKlass *dependee_ik = InstanceKlass::cast(dependee);
1925   Array<Method*>* dependee_methods = dependee_ik->methods();
1926   for (Dependencies::DepStream deps(this); deps.next(); ) {
1927     if (deps.type() == Dependencies::evol_method) {
1928       Method* method = deps.method_argument(0);
1929       for (int j = 0; j < dependee_methods->length(); j++) {
1930         if (dependee_methods->at(j) == method) {
1931           if (log_is_enabled(Debug, redefine, class, nmethod)) {
1932             ResourceMark rm;
1933             log_debug(redefine, class, nmethod)
1934               ("Found evol dependency of nmethod %s.%s(%s) compile_id=%d on method %s.%s(%s)",
1935                _method->method_holder()->external_name(),
1936                _method->name()->as_C_string(),
1937                _method->signature()->as_C_string(),
1938                compile_id(),
1939                method->method_holder()->external_name(),
1940                method->name()->as_C_string(),
1941                method->signature()->as_C_string());
1942           }
1943           if (TraceDependencies || LogCompilation)
1944             deps.log_dependency(dependee);
1945           return true;
1946         }
1947       }
1948     }
1949   }
1950   return false;
1951 }
1952 
1953 // Called from mark_for_deoptimization, when dependee is invalidated.
1954 bool nmethod::is_dependent_on_method(Method* dependee) {
1955   for (Dependencies::DepStream deps(this); deps.next(); ) {
1956     if (deps.type() != Dependencies::evol_method)
1957       continue;
1958     Method* method = deps.method_argument(0);
1959     if (method == dependee) return true;
1960   }
1961   return false;
1962 }
1963 
1964 
1965 bool nmethod::is_patchable_at(address instr_addr) {
1966   assert(insts_contains(instr_addr), "wrong nmethod used");
1967   if (is_zombie()) {
1968     // a zombie may never be patched
1969     return false;
1970   }
1971   return true;
1972 }
1973 
1974 
1975 address nmethod::continuation_for_implicit_exception(address pc) {
1976   // Exception happened outside inline-cache check code => we are inside
1977   // an active nmethod => use cpc to determine a return address
1978   int exception_offset = pc - code_begin();
1979   int cont_offset = ImplicitExceptionTable(this).at( exception_offset );
1980 #ifdef ASSERT
1981   if (cont_offset == 0) {
1982     Thread* thread = Thread::current();
1983     ResetNoHandleMark rnm; // Might be called from LEAF/QUICK ENTRY
1984     HandleMark hm(thread);
1985     ResourceMark rm(thread);
1986     CodeBlob* cb = CodeCache::find_blob(pc);
1987     assert(cb != NULL && cb == this, "");
1988     ttyLocker ttyl;
1989     tty->print_cr("implicit exception happened at " INTPTR_FORMAT, p2i(pc));
1990     print();
1991     method()->print_codes();
1992     print_code();
1993     print_pcs();
1994   }
1995 #endif
1996   if (cont_offset == 0) {
1997     // Let the normal error handling report the exception
1998     return NULL;
1999   }
2000   return code_begin() + cont_offset;
2001 }
2002 
2003 
2004 
2005 void nmethod_init() {
2006   // make sure you didn't forget to adjust the filler fields
2007   assert(sizeof(nmethod) % oopSize == 0, "nmethod size must be multiple of a word");
2008 }
2009 
2010 
2011 //-------------------------------------------------------------------------------------------
2012 
2013 
2014 // QQQ might we make this work from a frame??
2015 nmethodLocker::nmethodLocker(address pc) {
2016   CodeBlob* cb = CodeCache::find_blob(pc);
2017   guarantee(cb != NULL && cb->is_compiled(), "bad pc for a nmethod found");
2018   _nm = cb->as_compiled_method();
2019   lock_nmethod(_nm);
2020 }
2021 
2022 // Only JvmtiDeferredEvent::compiled_method_unload_event()
2023 // should pass zombie_ok == true.
2024 void nmethodLocker::lock_nmethod(CompiledMethod* cm, bool zombie_ok) {
2025   if (cm == NULL)  return;
2026   if (cm->is_aot()) return;  // FIXME: Revisit once _lock_count is added to aot_method
2027   nmethod* nm = cm->as_nmethod();
2028   Atomic::inc(&nm->_lock_count);
2029   assert(zombie_ok || !nm->is_zombie(), "cannot lock a zombie method");
2030 }
2031 
2032 void nmethodLocker::unlock_nmethod(CompiledMethod* cm) {
2033   if (cm == NULL)  return;
2034   if (cm->is_aot()) return;  // FIXME: Revisit once _lock_count is added to aot_method
2035   nmethod* nm = cm->as_nmethod();
2036   Atomic::dec(&nm->_lock_count);
2037   assert(nm->_lock_count >= 0, "unmatched nmethod lock/unlock");
2038 }
2039 
2040 
2041 // -----------------------------------------------------------------------------
2042 // Verification
2043 
2044 class VerifyOopsClosure: public OopClosure {
2045   nmethod* _nm;
2046   bool     _ok;
2047 public:
2048   VerifyOopsClosure(nmethod* nm) : _nm(nm), _ok(true) { }
2049   bool ok() { return _ok; }
2050   virtual void do_oop(oop* p) {
2051     if (oopDesc::is_oop_or_null(*p)) return;
2052     if (_ok) {
2053       _nm->print_nmethod(true);
2054       _ok = false;
2055     }
2056     tty->print_cr("*** non-oop " PTR_FORMAT " found at " PTR_FORMAT " (offset %d)",
2057                   p2i(*p), p2i(p), (int)((intptr_t)p - (intptr_t)_nm));
2058   }
2059   virtual void do_oop(narrowOop* p) { ShouldNotReachHere(); }
2060 };
2061 
2062 void nmethod::verify() {
2063 
2064   // Hmm. OSR methods can be deopted but not marked as zombie or not_entrant
2065   // seems odd.
2066 
2067   if (is_zombie() || is_not_entrant() || is_unloaded())
2068     return;
2069 
2070   // Make sure all the entry points are correctly aligned for patching.
2071   NativeJump::check_verified_entry_alignment(entry_point(), verified_entry_point());
2072 
2073   // assert(oopDesc::is_oop(method()), "must be valid");
2074 
2075   ResourceMark rm;
2076 
2077   if (!CodeCache::contains(this)) {
2078     fatal("nmethod at " INTPTR_FORMAT " not in zone", p2i(this));
2079   }
2080 
2081   if(is_native_method() )
2082     return;
2083 
2084   nmethod* nm = CodeCache::find_nmethod(verified_entry_point());
2085   if (nm != this) {
2086     fatal("findNMethod did not find this nmethod (" INTPTR_FORMAT ")", p2i(this));
2087   }
2088 
2089   for (PcDesc* p = scopes_pcs_begin(); p < scopes_pcs_end(); p++) {
2090     if (! p->verify(this)) {
2091       tty->print_cr("\t\tin nmethod at " INTPTR_FORMAT " (pcs)", p2i(this));
2092     }
2093   }
2094 
2095   VerifyOopsClosure voc(this);
2096   oops_do(&voc);
2097   assert(voc.ok(), "embedded oops must be OK");
2098   Universe::heap()->verify_nmethod(this);
2099 
2100   verify_scopes();
2101 }
2102 
2103 
2104 void nmethod::verify_interrupt_point(address call_site) {
2105   // Verify IC only when nmethod installation is finished.
2106   if (!is_not_installed()) {
2107     Thread *cur = Thread::current();
2108     if (CompiledIC_lock->owner() == cur ||
2109         ((cur->is_VM_thread() || cur->is_ConcurrentGC_thread()) &&
2110          SafepointSynchronize::is_at_safepoint())) {
2111       CompiledIC_at(this, call_site);
2112       CHECK_UNHANDLED_OOPS_ONLY(Thread::current()->clear_unhandled_oops());
2113     } else {
2114       MutexLocker ml_verify (CompiledIC_lock);
2115       CompiledIC_at(this, call_site);
2116     }
2117   }
2118 
2119   PcDesc* pd = pc_desc_at(nativeCall_at(call_site)->return_address());
2120   assert(pd != NULL, "PcDesc must exist");
2121   for (ScopeDesc* sd = new ScopeDesc(this, pd->scope_decode_offset(),
2122                                      pd->obj_decode_offset(), pd->should_reexecute(), pd->rethrow_exception(),
2123                                      pd->return_oop());
2124        !sd->is_top(); sd = sd->sender()) {
2125     sd->verify();
2126   }
2127 }
2128 
2129 void nmethod::verify_scopes() {
2130   if( !method() ) return;       // Runtime stubs have no scope
2131   if (method()->is_native()) return; // Ignore stub methods.
2132   // iterate through all interrupt point
2133   // and verify the debug information is valid.
2134   RelocIterator iter((nmethod*)this);
2135   while (iter.next()) {
2136     address stub = NULL;
2137     switch (iter.type()) {
2138       case relocInfo::virtual_call_type:
2139         verify_interrupt_point(iter.addr());
2140         break;
2141       case relocInfo::opt_virtual_call_type:
2142         stub = iter.opt_virtual_call_reloc()->static_stub(false);
2143         verify_interrupt_point(iter.addr());
2144         break;
2145       case relocInfo::static_call_type:
2146         stub = iter.static_call_reloc()->static_stub(false);
2147         //verify_interrupt_point(iter.addr());
2148         break;
2149       case relocInfo::runtime_call_type:
2150       case relocInfo::runtime_call_w_cp_type: {
2151         address destination = iter.reloc()->value();
2152         // Right now there is no way to find out which entries support
2153         // an interrupt point.  It would be nice if we had this
2154         // information in a table.
2155         break;
2156       }
2157       default:
2158         break;
2159     }
2160     assert(stub == NULL || stub_contains(stub), "static call stub outside stub section");
2161   }
2162 }
2163 
2164 
2165 // -----------------------------------------------------------------------------
2166 // Non-product code
2167 #ifndef PRODUCT
2168 
2169 class DebugScavengeRoot: public OopClosure {
2170   nmethod* _nm;
2171   bool     _ok;
2172 public:
2173   DebugScavengeRoot(nmethod* nm) : _nm(nm), _ok(true) { }
2174   bool ok() { return _ok; }
2175   virtual void do_oop(oop* p) {
2176     if ((*p) == NULL || !(*p)->is_scavengable())  return;
2177     if (_ok) {
2178       _nm->print_nmethod(true);
2179       _ok = false;
2180     }
2181     tty->print_cr("*** scavengable oop " PTR_FORMAT " found at " PTR_FORMAT " (offset %d)",
2182                   p2i(*p), p2i(p), (int)((intptr_t)p - (intptr_t)_nm));
2183     (*p)->print();
2184   }
2185   virtual void do_oop(narrowOop* p) { ShouldNotReachHere(); }
2186 };
2187 
2188 void nmethod::verify_scavenge_root_oops() {
2189   if (!on_scavenge_root_list()) {
2190     // Actually look inside, to verify the claim that it's clean.
2191     DebugScavengeRoot debug_scavenge_root(this);
2192     oops_do(&debug_scavenge_root);
2193     if (!debug_scavenge_root.ok())
2194       fatal("found an unadvertised bad scavengable oop in the code cache");
2195   }
2196   assert(scavenge_root_not_marked(), "");
2197 }
2198 
2199 #endif // PRODUCT
2200 
2201 // Printing operations
2202 
2203 void nmethod::print() const {
2204   ResourceMark rm;
2205   ttyLocker ttyl;   // keep the following output all in one block
2206 
2207   tty->print("Compiled method ");
2208 
2209   if (is_compiled_by_c1()) {
2210     tty->print("(c1) ");
2211   } else if (is_compiled_by_c2()) {
2212     tty->print("(c2) ");
2213   } else if (is_compiled_by_jvmci()) {
2214     tty->print("(JVMCI) ");
2215   } else {
2216     tty->print("(nm) ");
2217   }
2218 
2219   print_on(tty, NULL);
2220 
2221   if (WizardMode) {
2222     tty->print("((nmethod*) " INTPTR_FORMAT ") ", p2i(this));
2223     tty->print(" for method " INTPTR_FORMAT , p2i(method()));
2224     tty->print(" { ");
2225     tty->print_cr("%s ", state());
2226     if (on_scavenge_root_list())  tty->print("scavenge_root ");
2227     tty->print_cr("}:");
2228   }
2229   if (size              () > 0) tty->print_cr(" total in heap  [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
2230                                               p2i(this),
2231                                               p2i(this) + size(),
2232                                               size());
2233   if (relocation_size   () > 0) tty->print_cr(" relocation     [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
2234                                               p2i(relocation_begin()),
2235                                               p2i(relocation_end()),
2236                                               relocation_size());
2237   if (consts_size       () > 0) tty->print_cr(" constants      [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
2238                                               p2i(consts_begin()),
2239                                               p2i(consts_end()),
2240                                               consts_size());
2241   if (insts_size        () > 0) tty->print_cr(" main code      [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
2242                                               p2i(insts_begin()),
2243                                               p2i(insts_end()),
2244                                               insts_size());
2245   if (stub_size         () > 0) tty->print_cr(" stub code      [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
2246                                               p2i(stub_begin()),
2247                                               p2i(stub_end()),
2248                                               stub_size());
2249   if (oops_size         () > 0) tty->print_cr(" oops           [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
2250                                               p2i(oops_begin()),
2251                                               p2i(oops_end()),
2252                                               oops_size());
2253   if (metadata_size      () > 0) tty->print_cr(" metadata       [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
2254                                               p2i(metadata_begin()),
2255                                               p2i(metadata_end()),
2256                                               metadata_size());
2257   if (scopes_data_size  () > 0) tty->print_cr(" scopes data    [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
2258                                               p2i(scopes_data_begin()),
2259                                               p2i(scopes_data_end()),
2260                                               scopes_data_size());
2261   if (scopes_pcs_size   () > 0) tty->print_cr(" scopes pcs     [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
2262                                               p2i(scopes_pcs_begin()),
2263                                               p2i(scopes_pcs_end()),
2264                                               scopes_pcs_size());
2265   if (dependencies_size () > 0) tty->print_cr(" dependencies   [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
2266                                               p2i(dependencies_begin()),
2267                                               p2i(dependencies_end()),
2268                                               dependencies_size());
2269   if (handler_table_size() > 0) tty->print_cr(" handler table  [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
2270                                               p2i(handler_table_begin()),
2271                                               p2i(handler_table_end()),
2272                                               handler_table_size());
2273   if (nul_chk_table_size() > 0) tty->print_cr(" nul chk table  [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
2274                                               p2i(nul_chk_table_begin()),
2275                                               p2i(nul_chk_table_end()),
2276                                               nul_chk_table_size());
2277 }
2278 
2279 #ifndef PRODUCT
2280 
2281 void nmethod::print_scopes() {
2282   // Find the first pc desc for all scopes in the code and print it.
2283   ResourceMark rm;
2284   for (PcDesc* p = scopes_pcs_begin(); p < scopes_pcs_end(); p++) {
2285     if (p->scope_decode_offset() == DebugInformationRecorder::serialized_null)
2286       continue;
2287 
2288     ScopeDesc* sd = scope_desc_at(p->real_pc(this));
2289     while (sd != NULL) {
2290       sd->print_on(tty, p);
2291       sd = sd->sender();
2292     }
2293   }
2294 }
2295 
2296 void nmethod::print_dependencies() {
2297   ResourceMark rm;
2298   ttyLocker ttyl;   // keep the following output all in one block
2299   tty->print_cr("Dependencies:");
2300   for (Dependencies::DepStream deps(this); deps.next(); ) {
2301     deps.print_dependency();
2302     Klass* ctxk = deps.context_type();
2303     if (ctxk != NULL) {
2304       if (ctxk->is_instance_klass() && InstanceKlass::cast(ctxk)->is_dependent_nmethod(this)) {
2305         tty->print_cr("   [nmethod<=klass]%s", ctxk->external_name());
2306       }
2307     }
2308     deps.log_dependency();  // put it into the xml log also
2309   }
2310 }
2311 
2312 
2313 void nmethod::print_relocations() {
2314   ResourceMark m;       // in case methods get printed via the debugger
2315   tty->print_cr("relocations:");
2316   RelocIterator iter(this);
2317   iter.print();
2318 }
2319 
2320 
2321 void nmethod::print_pcs() {
2322   ResourceMark m;       // in case methods get printed via debugger
2323   tty->print_cr("pc-bytecode offsets:");
2324   for (PcDesc* p = scopes_pcs_begin(); p < scopes_pcs_end(); p++) {
2325     p->print(this);
2326   }
2327 }
2328 
2329 void nmethod::print_recorded_oops() {
2330   tty->print_cr("Recorded oops:");
2331   for (int i = 0; i < oops_count(); i++) {
2332     oop o = oop_at(i);
2333     tty->print("#%3d: " INTPTR_FORMAT " ", i, p2i(o));
2334     if (o == (oop)Universe::non_oop_word()) {
2335       tty->print("non-oop word");
2336     } else {
2337       o->print_value();
2338     }
2339     tty->cr();
2340   }
2341 }
2342 
2343 void nmethod::print_recorded_metadata() {
2344   tty->print_cr("Recorded metadata:");
2345   for (int i = 0; i < metadata_count(); i++) {
2346     Metadata* m = metadata_at(i);
2347     tty->print("#%3d: " INTPTR_FORMAT " ", i, p2i(m));
2348     if (m == (Metadata*)Universe::non_oop_word()) {
2349       tty->print("non-metadata word");
2350     } else {
2351       m->print_value_on_maybe_null(tty);
2352     }
2353     tty->cr();
2354   }
2355 }
2356 
2357 #endif // PRODUCT
2358 
2359 const char* nmethod::reloc_string_for(u_char* begin, u_char* end) {
2360   RelocIterator iter(this, begin, end);
2361   bool have_one = false;
2362   while (iter.next()) {
2363     have_one = true;
2364     switch (iter.type()) {
2365         case relocInfo::none:                  return "no_reloc";
2366         case relocInfo::oop_type: {
2367           stringStream st;
2368           oop_Relocation* r = iter.oop_reloc();
2369           oop obj = r->oop_value();
2370           st.print("oop(");
2371           if (obj == NULL) st.print("NULL");
2372           else obj->print_value_on(&st);
2373           st.print(")");
2374           return st.as_string();
2375         }
2376         case relocInfo::metadata_type: {
2377           stringStream st;
2378           metadata_Relocation* r = iter.metadata_reloc();
2379           Metadata* obj = r->metadata_value();
2380           st.print("metadata(");
2381           if (obj == NULL) st.print("NULL");
2382           else obj->print_value_on(&st);
2383           st.print(")");
2384           return st.as_string();
2385         }
2386         case relocInfo::runtime_call_type:
2387         case relocInfo::runtime_call_w_cp_type: {
2388           stringStream st;
2389           st.print("runtime_call");
2390           CallRelocation* r = (CallRelocation*)iter.reloc();
2391           address dest = r->destination();
2392           CodeBlob* cb = CodeCache::find_blob(dest);
2393           if (cb != NULL) {
2394             st.print(" %s", cb->name());
2395           } else {
2396             ResourceMark rm;
2397             const int buflen = 1024;
2398             char* buf = NEW_RESOURCE_ARRAY(char, buflen);
2399             int offset;
2400             if (os::dll_address_to_function_name(dest, buf, buflen, &offset)) {
2401               st.print(" %s", buf);
2402               if (offset != 0) {
2403                 st.print("+%d", offset);
2404               }
2405             }
2406           }
2407           return st.as_string();
2408         }
2409         case relocInfo::virtual_call_type: {
2410           stringStream st;
2411           st.print_raw("virtual_call");
2412           virtual_call_Relocation* r = iter.virtual_call_reloc();
2413           Method* m = r->method_value();
2414           if (m != NULL) {
2415             assert(m->is_method(), "");
2416             m->print_short_name(&st);
2417           }
2418           return st.as_string();
2419         }
2420         case relocInfo::opt_virtual_call_type: {
2421           stringStream st;
2422           st.print_raw("optimized virtual_call");
2423           opt_virtual_call_Relocation* r = iter.opt_virtual_call_reloc();
2424           Method* m = r->method_value();
2425           if (m != NULL) {
2426             assert(m->is_method(), "");
2427             m->print_short_name(&st);
2428           }
2429           return st.as_string();
2430         }
2431         case relocInfo::static_call_type: {
2432           stringStream st;
2433           st.print_raw("static_call");
2434           static_call_Relocation* r = iter.static_call_reloc();
2435           Method* m = r->method_value();
2436           if (m != NULL) {
2437             assert(m->is_method(), "");
2438             m->print_short_name(&st);
2439           }
2440           return st.as_string();
2441         }
2442         case relocInfo::static_stub_type:      return "static_stub";
2443         case relocInfo::external_word_type:    return "external_word";
2444         case relocInfo::internal_word_type:    return "internal_word";
2445         case relocInfo::section_word_type:     return "section_word";
2446         case relocInfo::poll_type:             return "poll";
2447         case relocInfo::poll_return_type:      return "poll_return";
2448         case relocInfo::type_mask:             return "type_bit_mask";
2449 
2450         default:
2451           break;
2452     }
2453   }
2454   return have_one ? "other" : NULL;
2455 }
2456 
2457 // Return a the last scope in (begin..end]
2458 ScopeDesc* nmethod::scope_desc_in(address begin, address end) {
2459   PcDesc* p = pc_desc_near(begin+1);
2460   if (p != NULL && p->real_pc(this) <= end) {
2461     return new ScopeDesc(this, p->scope_decode_offset(),
2462                          p->obj_decode_offset(), p->should_reexecute(), p->rethrow_exception(),
2463                          p->return_oop());
2464   }
2465   return NULL;
2466 }
2467 
2468 void nmethod::print_nmethod_labels(outputStream* stream, address block_begin) const {
2469   if (block_begin == entry_point())             stream->print_cr("[Entry Point]");
2470   if (block_begin == verified_entry_point())    stream->print_cr("[Verified Entry Point]");
2471   if (JVMCI_ONLY(_exception_offset >= 0 &&) block_begin == exception_begin())         stream->print_cr("[Exception Handler]");
2472   if (block_begin == stub_begin())              stream->print_cr("[Stub Code]");
2473   if (JVMCI_ONLY(_deopt_handler_begin != NULL &&) block_begin == deopt_handler_begin())     stream->print_cr("[Deopt Handler Code]");
2474 
2475   if (has_method_handle_invokes())
2476     if (block_begin == deopt_mh_handler_begin())  stream->print_cr("[Deopt MH Handler Code]");
2477 
2478   if (block_begin == consts_begin())            stream->print_cr("[Constants]");
2479 
2480   if (block_begin == entry_point()) {
2481     methodHandle m = method();
2482     if (m.not_null()) {
2483       stream->print("  # ");
2484       m->print_value_on(stream);
2485       stream->cr();
2486     }
2487     if (m.not_null() && !is_osr_method()) {
2488       ResourceMark rm;
2489       int sizeargs = m->size_of_parameters();
2490       BasicType* sig_bt = NEW_RESOURCE_ARRAY(BasicType, sizeargs);
2491       VMRegPair* regs   = NEW_RESOURCE_ARRAY(VMRegPair, sizeargs);
2492       {
2493         int sig_index = 0;
2494         if (!m->is_static())
2495           sig_bt[sig_index++] = T_OBJECT; // 'this'
2496         for (SignatureStream ss(m->signature()); !ss.at_return_type(); ss.next()) {
2497           BasicType t = ss.type();
2498           sig_bt[sig_index++] = t;
2499           if (type2size[t] == 2) {
2500             sig_bt[sig_index++] = T_VOID;
2501           } else {
2502             assert(type2size[t] == 1, "size is 1 or 2");
2503           }
2504         }
2505         assert(sig_index == sizeargs, "");
2506       }
2507       const char* spname = "sp"; // make arch-specific?
2508       intptr_t out_preserve = SharedRuntime::java_calling_convention(sig_bt, regs, sizeargs, false);
2509       int stack_slot_offset = this->frame_size() * wordSize;
2510       int tab1 = 14, tab2 = 24;
2511       int sig_index = 0;
2512       int arg_index = (m->is_static() ? 0 : -1);
2513       bool did_old_sp = false;
2514       for (SignatureStream ss(m->signature()); !ss.at_return_type(); ) {
2515         bool at_this = (arg_index == -1);
2516         bool at_old_sp = false;
2517         BasicType t = (at_this ? T_OBJECT : ss.type());
2518         assert(t == sig_bt[sig_index], "sigs in sync");
2519         if (at_this)
2520           stream->print("  # this: ");
2521         else
2522           stream->print("  # parm%d: ", arg_index);
2523         stream->move_to(tab1);
2524         VMReg fst = regs[sig_index].first();
2525         VMReg snd = regs[sig_index].second();
2526         if (fst->is_reg()) {
2527           stream->print("%s", fst->name());
2528           if (snd->is_valid())  {
2529             stream->print(":%s", snd->name());
2530           }
2531         } else if (fst->is_stack()) {
2532           int offset = fst->reg2stack() * VMRegImpl::stack_slot_size + stack_slot_offset;
2533           if (offset == stack_slot_offset)  at_old_sp = true;
2534           stream->print("[%s+0x%x]", spname, offset);
2535         } else {
2536           stream->print("reg%d:%d??", (int)(intptr_t)fst, (int)(intptr_t)snd);
2537         }
2538         stream->print(" ");
2539         stream->move_to(tab2);
2540         stream->print("= ");
2541         if (at_this) {
2542           m->method_holder()->print_value_on(stream);
2543         } else {
2544           bool did_name = false;
2545           if (!at_this && ss.is_object()) {
2546             Symbol* name = ss.as_symbol_or_null();
2547             if (name != NULL) {
2548               name->print_value_on(stream);
2549               did_name = true;
2550             }
2551           }
2552           if (!did_name)
2553             stream->print("%s", type2name(t));
2554         }
2555         if (at_old_sp) {
2556           stream->print("  (%s of caller)", spname);
2557           did_old_sp = true;
2558         }
2559         stream->cr();
2560         sig_index += type2size[t];
2561         arg_index += 1;
2562         if (!at_this)  ss.next();
2563       }
2564       if (!did_old_sp) {
2565         stream->print("  # ");
2566         stream->move_to(tab1);
2567         stream->print("[%s+0x%x]", spname, stack_slot_offset);
2568         stream->print("  (%s of caller)", spname);
2569         stream->cr();
2570       }
2571     }
2572   }
2573 }
2574 
2575 void nmethod::print_code_comment_on(outputStream* st, int column, u_char* begin, u_char* end) {
2576   // First, find an oopmap in (begin, end].
2577   // We use the odd half-closed interval so that oop maps and scope descs
2578   // which are tied to the byte after a call are printed with the call itself.
2579   address base = code_begin();
2580   ImmutableOopMapSet* oms = oop_maps();
2581   if (oms != NULL) {
2582     for (int i = 0, imax = oms->count(); i < imax; i++) {
2583       const ImmutableOopMapPair* pair = oms->pair_at(i);
2584       const ImmutableOopMap* om = pair->get_from(oms);
2585       address pc = base + pair->pc_offset();
2586       if (pc > begin) {
2587         if (pc <= end) {
2588           st->move_to(column);
2589           st->print("; ");
2590           om->print_on(st);
2591         }
2592         break;
2593       }
2594     }
2595   }
2596 
2597   // Print any debug info present at this pc.
2598   ScopeDesc* sd  = scope_desc_in(begin, end);
2599   if (sd != NULL) {
2600     st->move_to(column);
2601     if (sd->bci() == SynchronizationEntryBCI) {
2602       st->print(";*synchronization entry");
2603     } else {
2604       if (sd->method() == NULL) {
2605         st->print("method is NULL");
2606       } else if (sd->method()->is_native()) {
2607         st->print("method is native");
2608       } else {
2609         Bytecodes::Code bc = sd->method()->java_code_at(sd->bci());
2610         st->print(";*%s", Bytecodes::name(bc));
2611         switch (bc) {
2612         case Bytecodes::_invokevirtual:
2613         case Bytecodes::_invokespecial:
2614         case Bytecodes::_invokestatic:
2615         case Bytecodes::_invokeinterface:
2616           {
2617             Bytecode_invoke invoke(sd->method(), sd->bci());
2618             st->print(" ");
2619             if (invoke.name() != NULL)
2620               invoke.name()->print_symbol_on(st);
2621             else
2622               st->print("<UNKNOWN>");
2623             break;
2624           }
2625         case Bytecodes::_getfield:
2626         case Bytecodes::_putfield:
2627         case Bytecodes::_getstatic:
2628         case Bytecodes::_putstatic:
2629           {
2630             Bytecode_field field(sd->method(), sd->bci());
2631             st->print(" ");
2632             if (field.name() != NULL)
2633               field.name()->print_symbol_on(st);
2634             else
2635               st->print("<UNKNOWN>");
2636           }
2637         default:
2638           break;
2639         }
2640       }
2641       st->print(" {reexecute=%d rethrow=%d return_oop=%d}", sd->should_reexecute(), sd->rethrow_exception(), sd->return_oop());
2642     }
2643 
2644     // Print all scopes
2645     for (;sd != NULL; sd = sd->sender()) {
2646       st->move_to(column);
2647       st->print("; -");
2648       if (sd->method() == NULL) {
2649         st->print("method is NULL");
2650       } else {
2651         sd->method()->print_short_name(st);
2652       }
2653       int lineno = sd->method()->line_number_from_bci(sd->bci());
2654       if (lineno != -1) {
2655         st->print("@%d (line %d)", sd->bci(), lineno);
2656       } else {
2657         st->print("@%d", sd->bci());
2658       }
2659       st->cr();
2660     }
2661   }
2662 
2663   // Print relocation information
2664   const char* str = reloc_string_for(begin, end);
2665   if (str != NULL) {
2666     if (sd != NULL) st->cr();
2667     st->move_to(column);
2668     st->print(";   {%s}", str);
2669   }
2670   int cont_offset = ImplicitExceptionTable(this).at(begin - code_begin());
2671   if (cont_offset != 0) {
2672     st->move_to(column);
2673     st->print("; implicit exception: dispatches to " INTPTR_FORMAT, p2i(code_begin() + cont_offset));
2674   }
2675 
2676 }
2677 
2678 class DirectNativeCallWrapper: public NativeCallWrapper {
2679 private:
2680   NativeCall* _call;
2681 
2682 public:
2683   DirectNativeCallWrapper(NativeCall* call) : _call(call) {}
2684 
2685   virtual address destination() const { return _call->destination(); }
2686   virtual address instruction_address() const { return _call->instruction_address(); }
2687   virtual address next_instruction_address() const { return _call->next_instruction_address(); }
2688   virtual address return_address() const { return _call->return_address(); }
2689 
2690   virtual address get_resolve_call_stub(bool is_optimized) const {
2691     if (is_optimized) {
2692       return SharedRuntime::get_resolve_opt_virtual_call_stub();
2693     }
2694     return SharedRuntime::get_resolve_virtual_call_stub();
2695   }
2696 
2697   virtual void set_destination_mt_safe(address dest) {
2698 #if INCLUDE_AOT
2699     if (UseAOT) {
2700       CodeBlob* callee = CodeCache::find_blob(dest);
2701       CompiledMethod* cm = callee->as_compiled_method_or_null();
2702       if (cm != NULL && cm->is_far_code()) {
2703         // Temporary fix, see JDK-8143106
2704         CompiledDirectStaticCall* csc = CompiledDirectStaticCall::at(instruction_address());
2705         csc->set_to_far(methodHandle(cm->method()), dest);
2706         return;
2707       }
2708     }
2709 #endif
2710     _call->set_destination_mt_safe(dest);
2711   }
2712 
2713   virtual void set_to_interpreted(const methodHandle& method, CompiledICInfo& info) {
2714     CompiledDirectStaticCall* csc = CompiledDirectStaticCall::at(instruction_address());
2715 #if INCLUDE_AOT
2716     if (info.to_aot()) {
2717       csc->set_to_far(method, info.entry());
2718     } else
2719 #endif
2720     {
2721       csc->set_to_interpreted(method, info.entry());
2722     }
2723   }
2724 
2725   virtual void verify() const {
2726     // make sure code pattern is actually a call imm32 instruction
2727     _call->verify();
2728     if (os::is_MP()) {
2729       _call->verify_alignment();
2730     }
2731   }
2732 
2733   virtual void verify_resolve_call(address dest) const {
2734     CodeBlob* db = CodeCache::find_blob_unsafe(dest);
2735     assert(!db->is_adapter_blob(), "must use stub!");
2736   }
2737 
2738   virtual bool is_call_to_interpreted(address dest) const {
2739     CodeBlob* cb = CodeCache::find_blob(_call->instruction_address());
2740     return cb->contains(dest);
2741   }
2742 
2743   virtual bool is_safe_for_patching() const { return false; }
2744 
2745   virtual NativeInstruction* get_load_instruction(virtual_call_Relocation* r) const {
2746     return nativeMovConstReg_at(r->cached_value());
2747   }
2748 
2749   virtual void *get_data(NativeInstruction* instruction) const {
2750     return (void*)((NativeMovConstReg*) instruction)->data();
2751   }
2752 
2753   virtual void set_data(NativeInstruction* instruction, intptr_t data) {
2754     ((NativeMovConstReg*) instruction)->set_data(data);
2755   }
2756 };
2757 
2758 NativeCallWrapper* nmethod::call_wrapper_at(address call) const {
2759   return new DirectNativeCallWrapper((NativeCall*) call);
2760 }
2761 
2762 NativeCallWrapper* nmethod::call_wrapper_before(address return_pc) const {
2763   return new DirectNativeCallWrapper(nativeCall_before(return_pc));
2764 }
2765 
2766 address nmethod::call_instruction_address(address pc) const {
2767   if (NativeCall::is_call_before(pc)) {
2768     NativeCall *ncall = nativeCall_before(pc);
2769     return ncall->instruction_address();
2770   }
2771   return NULL;
2772 }
2773 
2774 CompiledStaticCall* nmethod::compiledStaticCall_at(Relocation* call_site) const {
2775   return CompiledDirectStaticCall::at(call_site);
2776 }
2777 
2778 CompiledStaticCall* nmethod::compiledStaticCall_at(address call_site) const {
2779   return CompiledDirectStaticCall::at(call_site);
2780 }
2781 
2782 CompiledStaticCall* nmethod::compiledStaticCall_before(address return_addr) const {
2783   return CompiledDirectStaticCall::before(return_addr);
2784 }
2785 
2786 #ifndef PRODUCT
2787 
2788 void nmethod::print_value_on(outputStream* st) const {
2789   st->print("nmethod");
2790   print_on(st, NULL);
2791 }
2792 
2793 void nmethod::print_calls(outputStream* st) {
2794   RelocIterator iter(this);
2795   while (iter.next()) {
2796     switch (iter.type()) {
2797     case relocInfo::virtual_call_type:
2798     case relocInfo::opt_virtual_call_type: {
2799       VerifyMutexLocker mc(CompiledIC_lock);
2800       CompiledIC_at(&iter)->print();
2801       break;
2802     }
2803     case relocInfo::static_call_type:
2804       st->print_cr("Static call at " INTPTR_FORMAT, p2i(iter.reloc()->addr()));
2805       CompiledDirectStaticCall::at(iter.reloc())->print();
2806       break;
2807     default:
2808       break;
2809     }
2810   }
2811 }
2812 
2813 void nmethod::print_handler_table() {
2814   ExceptionHandlerTable(this).print();
2815 }
2816 
2817 void nmethod::print_nul_chk_table() {
2818   ImplicitExceptionTable(this).print(code_begin());
2819 }
2820 
2821 void nmethod::print_statistics() {
2822   ttyLocker ttyl;
2823   if (xtty != NULL)  xtty->head("statistics type='nmethod'");
2824   native_nmethod_stats.print_native_nmethod_stats();
2825 #ifdef COMPILER1
2826   c1_java_nmethod_stats.print_nmethod_stats("C1");
2827 #endif
2828 #ifdef COMPILER2
2829   c2_java_nmethod_stats.print_nmethod_stats("C2");
2830 #endif
2831 #if INCLUDE_JVMCI
2832   jvmci_java_nmethod_stats.print_nmethod_stats("JVMCI");
2833 #endif
2834   unknown_java_nmethod_stats.print_nmethod_stats("Unknown");
2835   DebugInformationRecorder::print_statistics();
2836 #ifndef PRODUCT
2837   pc_nmethod_stats.print_pc_stats();
2838 #endif
2839   Dependencies::print_statistics();
2840   if (xtty != NULL)  xtty->tail("statistics");
2841 }
2842 
2843 #endif // !PRODUCT
2844 
2845 #if INCLUDE_JVMCI
2846 void nmethod::clear_jvmci_installed_code() {
2847   assert_locked_or_safepoint(Patching_lock);
2848   if (_jvmci_installed_code != NULL) {
2849     JNIHandles::destroy_weak_global(_jvmci_installed_code);
2850     _jvmci_installed_code = NULL;
2851   }
2852 }
2853 
2854 void nmethod::clear_speculation_log() {
2855   assert_locked_or_safepoint(Patching_lock);
2856   if (_speculation_log != NULL) {
2857     JNIHandles::destroy_weak_global(_speculation_log);
2858     _speculation_log = NULL;
2859   }
2860 }
2861 
2862 void nmethod::maybe_invalidate_installed_code() {
2863   assert(Patching_lock->is_locked() ||
2864          SafepointSynchronize::is_at_safepoint(), "should be performed under a lock for consistency");
2865   oop installed_code = JNIHandles::resolve(_jvmci_installed_code);
2866   if (installed_code != NULL) {
2867     // Update the values in the InstalledCode instance if it still refers to this nmethod
2868     nmethod* nm = (nmethod*)InstalledCode::address(installed_code);
2869     if (nm == this) {
2870       if (!is_alive()) {
2871         // Break the link between nmethod and InstalledCode such that the nmethod
2872         // can subsequently be flushed safely.  The link must be maintained while
2873         // the method could have live activations since invalidateInstalledCode
2874         // might want to invalidate all existing activations.
2875         InstalledCode::set_address(installed_code, 0);
2876         InstalledCode::set_entryPoint(installed_code, 0);
2877       } else if (is_not_entrant()) {
2878         // Remove the entry point so any invocation will fail but keep
2879         // the address link around that so that existing activations can
2880         // be invalidated.
2881         InstalledCode::set_entryPoint(installed_code, 0);
2882       }
2883     }
2884   }
2885   if (!is_alive()) {
2886     // Clear these out after the nmethod has been unregistered and any
2887     // updates to the InstalledCode instance have been performed.
2888     clear_jvmci_installed_code();
2889     clear_speculation_log();
2890   }
2891 }
2892 
2893 void nmethod::invalidate_installed_code(Handle installedCode, TRAPS) {
2894   if (installedCode() == NULL) {
2895     THROW(vmSymbols::java_lang_NullPointerException());
2896   }
2897   jlong nativeMethod = InstalledCode::address(installedCode);
2898   nmethod* nm = (nmethod*)nativeMethod;
2899   if (nm == NULL) {
2900     // Nothing to do
2901     return;
2902   }
2903 
2904   nmethodLocker nml(nm);
2905 #ifdef ASSERT
2906   {
2907     MutexLockerEx pl(Patching_lock, Mutex::_no_safepoint_check_flag);
2908     // This relationship can only be checked safely under a lock
2909     assert(!nm->is_alive() || nm->jvmci_installed_code() == installedCode(), "sanity check");
2910   }
2911 #endif
2912 
2913   if (nm->is_alive()) {
2914     // Invalidating the InstalledCode means we want the nmethod
2915     // to be deoptimized.
2916     nm->mark_for_deoptimization();
2917     VM_Deoptimize op;
2918     VMThread::execute(&op);
2919   }
2920 
2921   // Multiple threads could reach this point so we now need to
2922   // lock and re-check the link to the nmethod so that only one
2923   // thread clears it.
2924   MutexLockerEx pl(Patching_lock, Mutex::_no_safepoint_check_flag);
2925   if (InstalledCode::address(installedCode) == nativeMethod) {
2926       InstalledCode::set_address(installedCode, 0);
2927   }
2928 }
2929 
2930 oop nmethod::jvmci_installed_code() {
2931   return JNIHandles::resolve(_jvmci_installed_code);
2932 }
2933 
2934 oop nmethod::speculation_log() {
2935   return JNIHandles::resolve(_speculation_log);
2936 }
2937 
2938 char* nmethod::jvmci_installed_code_name(char* buf, size_t buflen) {
2939   if (!this->is_compiled_by_jvmci()) {
2940     return NULL;
2941   }
2942   oop installed_code = JNIHandles::resolve(_jvmci_installed_code);
2943   if (installed_code != NULL) {
2944     oop installed_code_name = NULL;
2945     if (installed_code->is_a(InstalledCode::klass())) {
2946       installed_code_name = InstalledCode::name(installed_code);
2947     }
2948     if (installed_code_name != NULL) {
2949       return java_lang_String::as_utf8_string(installed_code_name, buf, (int)buflen);
2950     }
2951   }
2952   return NULL;
2953 }
2954 #endif
--- EOF ---