1 /*
   2  * Copyright (c) 1997, 2017, Oracle and/or its affiliates. All rights reserved.
   3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   4  *
   5  * This code is free software; you can redistribute it and/or modify it
   6  * under the terms of the GNU General Public License version 2 only, as
   7  * published by the Free Software Foundation.
   8  *
   9  * This code is distributed in the hope that it will be useful, but WITHOUT
  10  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  11  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  12  * version 2 for more details (a copy is included in the LICENSE file that
  13  * accompanied this code).
  14  *
  15  * You should have received a copy of the GNU General Public License version
  16  * 2 along with this work; if not, write to the Free Software Foundation,
  17  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  18  *
  19  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
  20  * or visit www.oracle.com if you need additional information or have any
  21  * questions.
  22  *
  23  */
  24 
  25 #include "precompiled.hpp"
  26 #include "code/codeCache.hpp"
  27 #include "code/compiledIC.hpp"
  28 #include "code/dependencies.hpp"
  29 #include "code/nativeInst.hpp"
  30 #include "code/nmethod.hpp"
  31 #include "code/scopeDesc.hpp"
  32 #include "compiler/abstractCompiler.hpp"
  33 #include "compiler/compileBroker.hpp"
  34 #include "compiler/compileLog.hpp"
  35 #include "compiler/compilerDirectives.hpp"
  36 #include "compiler/directivesParser.hpp"
  37 #include "compiler/disassembler.hpp"
  38 #include "interpreter/bytecode.hpp"
  39 #include "logging/log.hpp"
  40 #include "logging/logStream.hpp"
  41 #include "memory/resourceArea.hpp"
  42 #include "oops/methodData.hpp"
  43 #include "oops/oop.inline.hpp"
  44 #include "prims/jvm.h"
  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                      = in_use;
 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   // verify nmethod
 442   debug_only(if (nm) nm->verify();) // might block
 443 
 444   if (nm != NULL) {
 445     nm->log_new_nmethod();
 446   }
 447 
 448   return nm;
 449 }
 450 
 451 nmethod* nmethod::new_nmethod(const methodHandle& method,
 452   int compile_id,
 453   int entry_bci,
 454   CodeOffsets* offsets,
 455   int orig_pc_offset,
 456   DebugInformationRecorder* debug_info,
 457   Dependencies* dependencies,
 458   CodeBuffer* code_buffer, int frame_size,
 459   OopMapSet* oop_maps,
 460   ExceptionHandlerTable* handler_table,
 461   ImplicitExceptionTable* nul_chk_table,
 462   AbstractCompiler* compiler,
 463   int comp_level
 464 #if INCLUDE_JVMCI
 465   , jweak installed_code,
 466   jweak speculationLog
 467 #endif
 468 )
 469 {
 470   assert(debug_info->oop_recorder() == code_buffer->oop_recorder(), "shared OR");
 471   code_buffer->finalize_oop_references(method);
 472   // create nmethod
 473   nmethod* nm = NULL;
 474   { MutexLockerEx mu(CodeCache_lock, Mutex::_no_safepoint_check_flag);
 475     int nmethod_size =
 476       CodeBlob::allocation_size(code_buffer, sizeof(nmethod))
 477       + adjust_pcs_size(debug_info->pcs_size())
 478       + align_up((int)dependencies->size_in_bytes(), oopSize)
 479       + align_up(handler_table->size_in_bytes()    , oopSize)
 480       + align_up(nul_chk_table->size_in_bytes()    , oopSize)
 481       + align_up(debug_info->data_size()           , oopSize);
 482 
 483     nm = new (nmethod_size, comp_level)
 484     nmethod(method(), compiler->type(), nmethod_size, compile_id, entry_bci, offsets,
 485             orig_pc_offset, debug_info, dependencies, code_buffer, frame_size,
 486             oop_maps,
 487             handler_table,
 488             nul_chk_table,
 489             compiler,
 490             comp_level
 491 #if INCLUDE_JVMCI
 492             , installed_code,
 493             speculationLog
 494 #endif
 495             );
 496 
 497     if (nm != NULL) {
 498       // To make dependency checking during class loading fast, record
 499       // the nmethod dependencies in the classes it is dependent on.
 500       // This allows the dependency checking code to simply walk the
 501       // class hierarchy above the loaded class, checking only nmethods
 502       // which are dependent on those classes.  The slow way is to
 503       // check every nmethod for dependencies which makes it linear in
 504       // the number of methods compiled.  For applications with a lot
 505       // classes the slow way is too slow.
 506       for (Dependencies::DepStream deps(nm); deps.next(); ) {
 507         if (deps.type() == Dependencies::call_site_target_value) {
 508           // CallSite dependencies are managed on per-CallSite instance basis.
 509           oop call_site = deps.argument_oop(0);
 510           MethodHandles::add_dependent_nmethod(call_site, nm);
 511         } else {
 512           Klass* klass = deps.context_type();
 513           if (klass == NULL) {
 514             continue;  // ignore things like evol_method
 515           }
 516           // record this nmethod as dependent on this klass
 517           InstanceKlass::cast(klass)->add_dependent_nmethod(nm);
 518         }
 519       }
 520       NOT_PRODUCT(if (nm != NULL)  note_java_nmethod(nm));
 521     }
 522   }
 523   // Do verification and logging outside CodeCache_lock.
 524   if (nm != NULL) {
 525     // Safepoints in nmethod::verify aren't allowed because nm hasn't been installed yet.
 526     DEBUG_ONLY(nm->verify();)
 527     nm->log_new_nmethod();
 528   }
 529   return nm;
 530 }
 531 
 532 // For native wrappers
 533 nmethod::nmethod(
 534   Method* method,
 535   CompilerType type,
 536   int nmethod_size,
 537   int compile_id,
 538   CodeOffsets* offsets,
 539   CodeBuffer* code_buffer,
 540   int frame_size,
 541   ByteSize basic_lock_owner_sp_offset,
 542   ByteSize basic_lock_sp_offset,
 543   OopMapSet* oop_maps )
 544   : CompiledMethod(method, "native nmethod", type, nmethod_size, sizeof(nmethod), code_buffer, offsets->value(CodeOffsets::Frame_Complete), frame_size, oop_maps, false),
 545   _native_receiver_sp_offset(basic_lock_owner_sp_offset),
 546   _native_basic_lock_sp_offset(basic_lock_sp_offset)
 547 {
 548   {
 549     int scopes_data_offset = 0;
 550     int deoptimize_offset       = 0;
 551     int deoptimize_mh_offset    = 0;
 552 
 553     debug_only(NoSafepointVerifier nsv;)
 554     assert_locked_or_safepoint(CodeCache_lock);
 555 
 556     init_defaults();
 557     _entry_bci               = InvocationEntryBci;
 558     // We have no exception handler or deopt handler make the
 559     // values something that will never match a pc like the nmethod vtable entry
 560     _exception_offset        = 0;
 561     _orig_pc_offset          = 0;
 562 
 563     _consts_offset           = data_offset();
 564     _stub_offset             = data_offset();
 565     _oops_offset             = data_offset();
 566     _metadata_offset         = _oops_offset         + align_up(code_buffer->total_oop_size(), oopSize);
 567     scopes_data_offset       = _metadata_offset     + align_up(code_buffer->total_metadata_size(), wordSize);
 568     _scopes_pcs_offset       = scopes_data_offset;
 569     _dependencies_offset     = _scopes_pcs_offset;
 570     _handler_table_offset    = _dependencies_offset;
 571     _nul_chk_table_offset    = _handler_table_offset;
 572     _nmethod_end_offset      = _nul_chk_table_offset;
 573     _compile_id              = compile_id;
 574     _comp_level              = CompLevel_none;
 575     _entry_point             = code_begin()          + offsets->value(CodeOffsets::Entry);
 576     _verified_entry_point    = code_begin()          + offsets->value(CodeOffsets::Verified_Entry);
 577     _osr_entry_point         = NULL;
 578     _exception_cache         = NULL;
 579     _pc_desc_container.reset_to(NULL);
 580     _hotness_counter         = NMethodSweeper::hotness_counter_reset_val();
 581 
 582     _scopes_data_begin = (address) this + scopes_data_offset;
 583     _deopt_handler_begin = (address) this + deoptimize_offset;
 584     _deopt_mh_handler_begin = (address) this + deoptimize_mh_offset;
 585 
 586     code_buffer->copy_code_and_locs_to(this);
 587     code_buffer->copy_values_to(this);
 588     if (ScavengeRootsInCode) {
 589       Universe::heap()->register_nmethod(this);
 590     }
 591     debug_only(Universe::heap()->verify_nmethod(this));
 592     CodeCache::commit(this);
 593   }
 594 
 595   if (PrintNativeNMethods || PrintDebugInfo || PrintRelocations || PrintDependencies) {
 596     ttyLocker ttyl;  // keep the following output all in one block
 597     // This output goes directly to the tty, not the compiler log.
 598     // To enable tools to match it up with the compilation activity,
 599     // be sure to tag this tty output with the compile ID.
 600     if (xtty != NULL) {
 601       xtty->begin_head("print_native_nmethod");
 602       xtty->method(_method);
 603       xtty->stamp();
 604       xtty->end_head(" address='" INTPTR_FORMAT "'", (intptr_t) this);
 605     }
 606     // print the header part first
 607     print();
 608     // then print the requested information
 609     if (PrintNativeNMethods) {
 610       print_code();
 611       if (oop_maps != NULL) {
 612         oop_maps->print();
 613       }
 614     }
 615     if (PrintRelocations) {
 616       print_relocations();
 617     }
 618     if (xtty != NULL) {
 619       xtty->tail("print_native_nmethod");
 620     }
 621   }
 622 }
 623 
 624 void* nmethod::operator new(size_t size, int nmethod_size, int comp_level) throw () {
 625   return CodeCache::allocate(nmethod_size, CodeCache::get_code_blob_type(comp_level));
 626 }
 627 
 628 nmethod::nmethod(
 629   Method* method,
 630   CompilerType type,
 631   int nmethod_size,
 632   int compile_id,
 633   int entry_bci,
 634   CodeOffsets* offsets,
 635   int orig_pc_offset,
 636   DebugInformationRecorder* debug_info,
 637   Dependencies* dependencies,
 638   CodeBuffer *code_buffer,
 639   int frame_size,
 640   OopMapSet* oop_maps,
 641   ExceptionHandlerTable* handler_table,
 642   ImplicitExceptionTable* nul_chk_table,
 643   AbstractCompiler* compiler,
 644   int comp_level
 645 #if INCLUDE_JVMCI
 646   , jweak installed_code,
 647   jweak speculation_log
 648 #endif
 649   )
 650   : CompiledMethod(method, "nmethod", type, nmethod_size, sizeof(nmethod), code_buffer, offsets->value(CodeOffsets::Frame_Complete), frame_size, oop_maps, false),
 651   _native_receiver_sp_offset(in_ByteSize(-1)),
 652   _native_basic_lock_sp_offset(in_ByteSize(-1))
 653 {
 654   assert(debug_info->oop_recorder() == code_buffer->oop_recorder(), "shared OR");
 655   {
 656     debug_only(NoSafepointVerifier nsv;)
 657     assert_locked_or_safepoint(CodeCache_lock);
 658 
 659     _deopt_handler_begin = (address) this;
 660     _deopt_mh_handler_begin = (address) this;
 661 
 662     init_defaults();
 663     _entry_bci               = entry_bci;
 664     _compile_id              = compile_id;
 665     _comp_level              = comp_level;
 666     _orig_pc_offset          = orig_pc_offset;
 667     _hotness_counter         = NMethodSweeper::hotness_counter_reset_val();
 668 
 669     // Section offsets
 670     _consts_offset           = content_offset()      + code_buffer->total_offset_of(code_buffer->consts());
 671     _stub_offset             = content_offset()      + code_buffer->total_offset_of(code_buffer->stubs());
 672     set_ctable_begin(header_begin() + _consts_offset);
 673 
 674 #if INCLUDE_JVMCI
 675     _jvmci_installed_code = installed_code;
 676     _speculation_log = speculation_log;
 677     oop obj = JNIHandles::resolve(installed_code);
 678     if (obj == NULL || (obj->is_a(HotSpotNmethod::klass()) && HotSpotNmethod::isDefault(obj))) {
 679       _jvmci_installed_code_triggers_unloading = false;
 680     } else {
 681       _jvmci_installed_code_triggers_unloading = true;
 682     }
 683 
 684     if (compiler->is_jvmci()) {
 685       // JVMCI might not produce any stub sections
 686       if (offsets->value(CodeOffsets::Exceptions) != -1) {
 687         _exception_offset        = code_offset()          + offsets->value(CodeOffsets::Exceptions);
 688       } else {
 689         _exception_offset = -1;
 690       }
 691       if (offsets->value(CodeOffsets::Deopt) != -1) {
 692         _deopt_handler_begin       = (address) this + code_offset()          + offsets->value(CodeOffsets::Deopt);
 693       } else {
 694         _deopt_handler_begin = NULL;
 695       }
 696       if (offsets->value(CodeOffsets::DeoptMH) != -1) {
 697         _deopt_mh_handler_begin  = (address) this + code_offset()          + offsets->value(CodeOffsets::DeoptMH);
 698       } else {
 699         _deopt_mh_handler_begin = NULL;
 700       }
 701     } else {
 702 #endif
 703     // Exception handler and deopt handler are in the stub section
 704     assert(offsets->value(CodeOffsets::Exceptions) != -1, "must be set");
 705     assert(offsets->value(CodeOffsets::Deopt     ) != -1, "must be set");
 706 
 707     _exception_offset       = _stub_offset          + offsets->value(CodeOffsets::Exceptions);
 708     _deopt_handler_begin    = (address) this + _stub_offset          + offsets->value(CodeOffsets::Deopt);
 709     if (offsets->value(CodeOffsets::DeoptMH) != -1) {
 710       _deopt_mh_handler_begin  = (address) this + _stub_offset          + offsets->value(CodeOffsets::DeoptMH);
 711     } else {
 712       _deopt_mh_handler_begin  = NULL;
 713 #if INCLUDE_JVMCI
 714     }
 715 #endif
 716     }
 717     if (offsets->value(CodeOffsets::UnwindHandler) != -1) {
 718       _unwind_handler_offset = code_offset()         + offsets->value(CodeOffsets::UnwindHandler);
 719     } else {
 720       _unwind_handler_offset = -1;
 721     }
 722 
 723     _oops_offset             = data_offset();
 724     _metadata_offset         = _oops_offset          + align_up(code_buffer->total_oop_size(), oopSize);
 725     int scopes_data_offset   = _metadata_offset      + align_up(code_buffer->total_metadata_size(), wordSize);
 726 
 727     _scopes_pcs_offset       = scopes_data_offset    + align_up(debug_info->data_size       (), oopSize);
 728     _dependencies_offset     = _scopes_pcs_offset    + adjust_pcs_size(debug_info->pcs_size());
 729     _handler_table_offset    = _dependencies_offset  + align_up((int)dependencies->size_in_bytes (), oopSize);
 730     _nul_chk_table_offset    = _handler_table_offset + align_up(handler_table->size_in_bytes(), oopSize);
 731     _nmethod_end_offset      = _nul_chk_table_offset + align_up(nul_chk_table->size_in_bytes(), oopSize);
 732     _entry_point             = code_begin()          + offsets->value(CodeOffsets::Entry);
 733     _verified_entry_point    = code_begin()          + offsets->value(CodeOffsets::Verified_Entry);
 734     _osr_entry_point         = code_begin()          + offsets->value(CodeOffsets::OSR_Entry);
 735     _exception_cache         = NULL;
 736 
 737     _scopes_data_begin = (address) this + scopes_data_offset;
 738 
 739     _pc_desc_container.reset_to(scopes_pcs_begin());
 740 
 741     code_buffer->copy_code_and_locs_to(this);
 742     // Copy contents of ScopeDescRecorder to nmethod
 743     code_buffer->copy_values_to(this);
 744     debug_info->copy_to(this);
 745     dependencies->copy_to(this);
 746     if (ScavengeRootsInCode) {
 747       Universe::heap()->register_nmethod(this);
 748     }
 749     debug_only(Universe::heap()->verify_nmethod(this));
 750 
 751     CodeCache::commit(this);
 752 
 753     // Copy contents of ExceptionHandlerTable to nmethod
 754     handler_table->copy_to(this);
 755     nul_chk_table->copy_to(this);
 756 
 757     // we use the information of entry points to find out if a method is
 758     // static or non static
 759     assert(compiler->is_c2() || compiler->is_jvmci() ||
 760            _method->is_static() == (entry_point() == _verified_entry_point),
 761            " entry points must be same for static methods and vice versa");
 762   }
 763 }
 764 
 765 // Print a short set of xml attributes to identify this nmethod.  The
 766 // output should be embedded in some other element.
 767 void nmethod::log_identity(xmlStream* log) const {
 768   log->print(" compile_id='%d'", compile_id());
 769   const char* nm_kind = compile_kind();
 770   if (nm_kind != NULL)  log->print(" compile_kind='%s'", nm_kind);
 771   log->print(" compiler='%s'", compiler_name());
 772   if (TieredCompilation) {
 773     log->print(" level='%d'", comp_level());
 774   }
 775 }
 776 
 777 
 778 #define LOG_OFFSET(log, name)                    \
 779   if (p2i(name##_end()) - p2i(name##_begin())) \
 780     log->print(" " XSTR(name) "_offset='" INTX_FORMAT "'"    , \
 781                p2i(name##_begin()) - p2i(this))
 782 
 783 
 784 void nmethod::log_new_nmethod() const {
 785   if (LogCompilation && xtty != NULL) {
 786     ttyLocker ttyl;
 787     HandleMark hm;
 788     xtty->begin_elem("nmethod");
 789     log_identity(xtty);
 790     xtty->print(" entry='" INTPTR_FORMAT "' size='%d'", p2i(code_begin()), size());
 791     xtty->print(" address='" INTPTR_FORMAT "'", p2i(this));
 792 
 793     LOG_OFFSET(xtty, relocation);
 794     LOG_OFFSET(xtty, consts);
 795     LOG_OFFSET(xtty, insts);
 796     LOG_OFFSET(xtty, stub);
 797     LOG_OFFSET(xtty, scopes_data);
 798     LOG_OFFSET(xtty, scopes_pcs);
 799     LOG_OFFSET(xtty, dependencies);
 800     LOG_OFFSET(xtty, handler_table);
 801     LOG_OFFSET(xtty, nul_chk_table);
 802     LOG_OFFSET(xtty, oops);
 803     LOG_OFFSET(xtty, metadata);
 804 
 805     xtty->method(method());
 806     xtty->stamp();
 807     xtty->end_elem();
 808   }
 809 }
 810 
 811 #undef LOG_OFFSET
 812 
 813 
 814 // Print out more verbose output usually for a newly created nmethod.
 815 void nmethod::print_on(outputStream* st, const char* msg) const {
 816   if (st != NULL) {
 817     ttyLocker ttyl;
 818     if (WizardMode) {
 819       CompileTask::print(st, this, msg, /*short_form:*/ true);
 820       st->print_cr(" (" INTPTR_FORMAT ")", p2i(this));
 821     } else {
 822       CompileTask::print(st, this, msg, /*short_form:*/ false);
 823     }
 824   }
 825 }
 826 
 827 void nmethod::maybe_print_nmethod(DirectiveSet* directive) {
 828   bool printnmethods = directive->PrintAssemblyOption || directive->PrintNMethodsOption;
 829   if (printnmethods || PrintDebugInfo || PrintRelocations || PrintDependencies || PrintExceptionHandlers) {
 830     print_nmethod(printnmethods);
 831   }
 832 }
 833 
 834 void nmethod::print_nmethod(bool printmethod) {
 835   ttyLocker ttyl;  // keep the following output all in one block
 836   if (xtty != NULL) {
 837     xtty->begin_head("print_nmethod");
 838     xtty->stamp();
 839     xtty->end_head();
 840   }
 841   // print the header part first
 842   print();
 843   // then print the requested information
 844   if (printmethod) {
 845     print_code();
 846     print_pcs();
 847     if (oop_maps()) {
 848       oop_maps()->print();
 849     }
 850   }
 851   if (printmethod || PrintDebugInfo || CompilerOracle::has_option_string(_method, "PrintDebugInfo")) {
 852     print_scopes();
 853   }
 854   if (printmethod || PrintRelocations || CompilerOracle::has_option_string(_method, "PrintRelocations")) {
 855     print_relocations();
 856   }
 857   if (printmethod || PrintDependencies || CompilerOracle::has_option_string(_method, "PrintDependencies")) {
 858     print_dependencies();
 859   }
 860   if (printmethod || PrintExceptionHandlers) {
 861     print_handler_table();
 862     print_nul_chk_table();
 863   }
 864   if (printmethod) {
 865     print_recorded_oops();
 866     print_recorded_metadata();
 867   }
 868   if (xtty != NULL) {
 869     xtty->tail("print_nmethod");
 870   }
 871 }
 872 
 873 
 874 // Promote one word from an assembly-time handle to a live embedded oop.
 875 inline void nmethod::initialize_immediate_oop(oop* dest, jobject handle) {
 876   if (handle == NULL ||
 877       // As a special case, IC oops are initialized to 1 or -1.
 878       handle == (jobject) Universe::non_oop_word()) {
 879     (*dest) = (oop) handle;
 880   } else {
 881     (*dest) = JNIHandles::resolve_non_null(handle);
 882   }
 883 }
 884 
 885 
 886 // Have to have the same name because it's called by a template
 887 void nmethod::copy_values(GrowableArray<jobject>* array) {
 888   int length = array->length();
 889   assert((address)(oops_begin() + length) <= (address)oops_end(), "oops big enough");
 890   oop* dest = oops_begin();
 891   for (int index = 0 ; index < length; index++) {
 892     initialize_immediate_oop(&dest[index], array->at(index));
 893   }
 894 
 895   // Now we can fix up all the oops in the code.  We need to do this
 896   // in the code because the assembler uses jobjects as placeholders.
 897   // The code and relocations have already been initialized by the
 898   // CodeBlob constructor, so it is valid even at this early point to
 899   // iterate over relocations and patch the code.
 900   fix_oop_relocations(NULL, NULL, /*initialize_immediates=*/ true);
 901 }
 902 
 903 void nmethod::copy_values(GrowableArray<Metadata*>* array) {
 904   int length = array->length();
 905   assert((address)(metadata_begin() + length) <= (address)metadata_end(), "big enough");
 906   Metadata** dest = metadata_begin();
 907   for (int index = 0 ; index < length; index++) {
 908     dest[index] = array->at(index);
 909   }
 910 }
 911 
 912 void nmethod::fix_oop_relocations(address begin, address end, bool initialize_immediates) {
 913   // re-patch all oop-bearing instructions, just in case some oops moved
 914   RelocIterator iter(this, begin, end);
 915   while (iter.next()) {
 916     if (iter.type() == relocInfo::oop_type) {
 917       oop_Relocation* reloc = iter.oop_reloc();
 918       if (initialize_immediates && reloc->oop_is_immediate()) {
 919         oop* dest = reloc->oop_addr();
 920         initialize_immediate_oop(dest, (jobject) *dest);
 921       }
 922       // Refresh the oop-related bits of this instruction.
 923       reloc->fix_oop_relocation();
 924     } else if (iter.type() == relocInfo::metadata_type) {
 925       metadata_Relocation* reloc = iter.metadata_reloc();
 926       reloc->fix_metadata_relocation();
 927     }
 928   }
 929 }
 930 
 931 
 932 void nmethod::verify_clean_inline_caches() {
 933   assert_locked_or_safepoint(CompiledIC_lock);
 934 
 935   // If the method is not entrant or zombie then a JMP is plastered over the
 936   // first few bytes.  If an oop in the old code was there, that oop
 937   // should not get GC'd.  Skip the first few bytes of oops on
 938   // not-entrant methods.
 939   address low_boundary = verified_entry_point();
 940   if (!is_in_use()) {
 941     low_boundary += NativeJump::instruction_size;
 942     // %%% Note:  On SPARC we patch only a 4-byte trap, not a full NativeJump.
 943     // This means that the low_boundary is going to be a little too high.
 944     // This shouldn't matter, since oops of non-entrant methods are never used.
 945     // In fact, why are we bothering to look at oops in a non-entrant method??
 946   }
 947 
 948   ResourceMark rm;
 949   RelocIterator iter(this, low_boundary);
 950   while(iter.next()) {
 951     switch(iter.type()) {
 952       case relocInfo::virtual_call_type:
 953       case relocInfo::opt_virtual_call_type: {
 954         CompiledIC *ic = CompiledIC_at(&iter);
 955         // Ok, to lookup references to zombies here
 956         CodeBlob *cb = CodeCache::find_blob_unsafe(ic->ic_destination());
 957         nmethod* nm = cb->as_nmethod_or_null();
 958         if( nm != NULL ) {
 959           // Verify that inline caches pointing to both zombie and not_entrant methods are clean
 960           if (!nm->is_in_use() || (nm->method()->code() != nm)) {
 961             assert(ic->is_clean(), "IC should be clean");
 962           }
 963         }
 964         break;
 965       }
 966       case relocInfo::static_call_type: {
 967         CompiledStaticCall *csc = compiledStaticCall_at(iter.reloc());
 968         CodeBlob *cb = CodeCache::find_blob_unsafe(csc->destination());
 969         nmethod* nm = cb->as_nmethod_or_null();
 970         if( nm != NULL ) {
 971           // Verify that inline caches pointing to both zombie and not_entrant methods are clean
 972           if (!nm->is_in_use() || (nm->method()->code() != nm)) {
 973             assert(csc->is_clean(), "IC should be clean");
 974           }
 975         }
 976         break;
 977       }
 978       default:
 979         break;
 980     }
 981   }
 982 }
 983 
 984 // This is a private interface with the sweeper.
 985 void nmethod::mark_as_seen_on_stack() {
 986   assert(is_alive(), "Must be an alive method");
 987   // Set the traversal mark to ensure that the sweeper does 2
 988   // cleaning passes before moving to zombie.
 989   set_stack_traversal_mark(NMethodSweeper::traversal_count());
 990 }
 991 
 992 // Tell if a non-entrant method can be converted to a zombie (i.e.,
 993 // there are no activations on the stack, not in use by the VM,
 994 // and not in use by the ServiceThread)
 995 bool nmethod::can_convert_to_zombie() {
 996   assert(is_not_entrant(), "must be a non-entrant method");
 997 
 998   // Since the nmethod sweeper only does partial sweep the sweeper's traversal
 999   // count can be greater than the stack traversal count before it hits the
1000   // nmethod for the second time.
1001   return stack_traversal_mark()+1 < NMethodSweeper::traversal_count() &&
1002          !is_locked_by_vm();
1003 }
1004 
1005 void nmethod::inc_decompile_count() {
1006   if (!is_compiled_by_c2() && !is_compiled_by_jvmci()) return;
1007   // Could be gated by ProfileTraps, but do not bother...
1008   Method* m = method();
1009   if (m == NULL)  return;
1010   MethodData* mdo = m->method_data();
1011   if (mdo == NULL)  return;
1012   // There is a benign race here.  See comments in methodData.hpp.
1013   mdo->inc_decompile_count();
1014 }
1015 
1016 void nmethod::make_unloaded(BoolObjectClosure* is_alive, oop cause) {
1017 
1018   post_compiled_method_unload();
1019 
1020   // Since this nmethod is being unloaded, make sure that dependencies
1021   // recorded in instanceKlasses get flushed and pass non-NULL closure to
1022   // indicate that this work is being done during a GC.
1023   assert(Universe::heap()->is_gc_active(), "should only be called during gc");
1024   assert(is_alive != NULL, "Should be non-NULL");
1025   // A non-NULL is_alive closure indicates that this is being called during GC.
1026   flush_dependencies(is_alive);
1027 
1028   // Break cycle between nmethod & method
1029   LogTarget(Trace, class, unload) lt;
1030   if (lt.is_enabled()) {
1031     LogStream ls(lt);
1032     ls.print_cr("making nmethod " INTPTR_FORMAT
1033                   " unloadable, Method*(" INTPTR_FORMAT
1034                   "), cause(" INTPTR_FORMAT ")",
1035                   p2i(this), p2i(_method), p2i(cause));
1036   }
1037   // Unlink the osr method, so we do not look this up again
1038   if (is_osr_method()) {
1039     // Invalidate the osr nmethod only once
1040     if (is_in_use()) {
1041       invalidate_osr_method();
1042     }
1043 #ifdef ASSERT
1044     if (method() != NULL) {
1045       // Make sure osr nmethod is invalidated, i.e. not on the list
1046       bool found = method()->method_holder()->remove_osr_nmethod(this);
1047       assert(!found, "osr nmethod should have been invalidated");
1048     }
1049 #endif
1050   }
1051 
1052   // If _method is already NULL the Method* is about to be unloaded,
1053   // so we don't have to break the cycle. Note that it is possible to
1054   // have the Method* live here, in case we unload the nmethod because
1055   // it is pointing to some oop (other than the Method*) being unloaded.
1056   if (_method != NULL) {
1057     // OSR methods point to the Method*, but the Method* does not
1058     // point back!
1059     if (_method->code() == this) {
1060       _method->clear_code(); // Break a cycle
1061     }
1062     _method = NULL;            // Clear the method of this dead nmethod
1063   }
1064 
1065   // Make the class unloaded - i.e., change state and notify sweeper
1066   assert(SafepointSynchronize::is_at_safepoint(), "must be at safepoint");
1067   if (is_in_use()) {
1068     // Transitioning directly from live to unloaded -- so
1069     // we need to force a cache clean-up; remember this
1070     // for later on.
1071     CodeCache::set_needs_cache_clean(true);
1072   }
1073 
1074   // Unregister must be done before the state change
1075   Universe::heap()->unregister_nmethod(this);
1076 
1077   _state = unloaded;
1078 
1079   // Log the unloading.
1080   log_state_change();
1081 
1082 #if INCLUDE_JVMCI
1083   // The method can only be unloaded after the pointer to the installed code
1084   // Java wrapper is no longer alive. Here we need to clear out this weak
1085   // reference to the dead object.
1086   maybe_invalidate_installed_code();
1087 #endif
1088 
1089   // The Method* is gone at this point
1090   assert(_method == NULL, "Tautology");
1091 
1092   set_osr_link(NULL);
1093   NMethodSweeper::report_state_change(this);
1094 }
1095 
1096 void nmethod::invalidate_osr_method() {
1097   assert(_entry_bci != InvocationEntryBci, "wrong kind of nmethod");
1098   // Remove from list of active nmethods
1099   if (method() != NULL) {
1100     method()->method_holder()->remove_osr_nmethod(this);
1101   }
1102 }
1103 
1104 void nmethod::log_state_change() const {
1105   if (LogCompilation) {
1106     if (xtty != NULL) {
1107       ttyLocker ttyl;  // keep the following output all in one block
1108       if (_state == unloaded) {
1109         xtty->begin_elem("make_unloaded thread='" UINTX_FORMAT "'",
1110                          os::current_thread_id());
1111       } else {
1112         xtty->begin_elem("make_not_entrant thread='" UINTX_FORMAT "'%s",
1113                          os::current_thread_id(),
1114                          (_state == zombie ? " zombie='1'" : ""));
1115       }
1116       log_identity(xtty);
1117       xtty->stamp();
1118       xtty->end_elem();
1119     }
1120   }
1121 
1122   const char *state_msg = _state == zombie ? "made zombie" : "made not entrant";
1123   CompileTask::print_ul(this, state_msg);
1124   if (PrintCompilation && _state != unloaded) {
1125     print_on(tty, state_msg);
1126   }
1127 }
1128 
1129 /**
1130  * Common functionality for both make_not_entrant and make_zombie
1131  */
1132 bool nmethod::make_not_entrant_or_zombie(unsigned int state) {
1133   assert(state == zombie || state == not_entrant, "must be zombie or not_entrant");
1134   assert(!is_zombie(), "should not already be a zombie");
1135 
1136   if (_state == state) {
1137     // Avoid taking the lock if already in required state.
1138     // This is safe from races because the state is an end-state,
1139     // which the nmethod cannot back out of once entered.
1140     // No need for fencing either.
1141     return false;
1142   }
1143 
1144   // Make sure neither the nmethod nor the method is flushed in case of a safepoint in code below.
1145   nmethodLocker nml(this);
1146   methodHandle the_method(method());
1147   NoSafepointVerifier nsv;
1148 
1149   // during patching, depending on the nmethod state we must notify the GC that
1150   // code has been unloaded, unregistering it. We cannot do this right while
1151   // holding the Patching_lock because we need to use the CodeCache_lock. This
1152   // would be prone to deadlocks.
1153   // This flag is used to remember whether we need to later lock and unregister.
1154   bool nmethod_needs_unregister = false;
1155 
1156   {
1157     // invalidate osr nmethod before acquiring the patching lock since
1158     // they both acquire leaf locks and we don't want a deadlock.
1159     // This logic is equivalent to the logic below for patching the
1160     // verified entry point of regular methods. We check that the
1161     // nmethod is in use to ensure that it is invalidated only once.
1162     if (is_osr_method() && is_in_use()) {
1163       // this effectively makes the osr nmethod not entrant
1164       invalidate_osr_method();
1165     }
1166 
1167     // Enter critical section.  Does not block for safepoint.
1168     MutexLockerEx pl(Patching_lock, Mutex::_no_safepoint_check_flag);
1169 
1170     if (_state == state) {
1171       // another thread already performed this transition so nothing
1172       // to do, but return false to indicate this.
1173       return false;
1174     }
1175 
1176     // The caller can be calling the method statically or through an inline
1177     // cache call.
1178     if (!is_osr_method() && !is_not_entrant()) {
1179       NativeJump::patch_verified_entry(entry_point(), verified_entry_point(),
1180                   SharedRuntime::get_handle_wrong_method_stub());
1181     }
1182 
1183     if (is_in_use() && update_recompile_counts()) {
1184       // It's a true state change, so mark the method as decompiled.
1185       // Do it only for transition from alive.
1186       inc_decompile_count();
1187     }
1188 
1189     // If the state is becoming a zombie, signal to unregister the nmethod with
1190     // the heap.
1191     // This nmethod may have already been unloaded during a full GC.
1192     if ((state == zombie) && !is_unloaded()) {
1193       nmethod_needs_unregister = true;
1194     }
1195 
1196     // Must happen before state change. Otherwise we have a race condition in
1197     // nmethod::can_not_entrant_be_converted(). I.e., a method can immediately
1198     // transition its state from 'not_entrant' to 'zombie' without having to wait
1199     // for stack scanning.
1200     if (state == not_entrant) {
1201       mark_as_seen_on_stack();
1202       OrderAccess::storestore(); // _stack_traversal_mark and _state
1203     }
1204 
1205     // Change state
1206     _state = state;
1207 
1208     // Log the transition once
1209     log_state_change();
1210 
1211     // Invalidate while holding the patching lock
1212     JVMCI_ONLY(maybe_invalidate_installed_code());
1213 
1214     // Remove nmethod from method.
1215     // We need to check if both the _code and _from_compiled_code_entry_point
1216     // refer to this nmethod because there is a race in setting these two fields
1217     // in Method* as seen in bugid 4947125.
1218     // If the vep() points to the zombie nmethod, the memory for the nmethod
1219     // could be flushed and the compiler and vtable stubs could still call
1220     // through it.
1221     if (method() != NULL && (method()->code() == this ||
1222                              method()->from_compiled_entry() == verified_entry_point())) {
1223       HandleMark hm;
1224       method()->clear_code(false /* already owns Patching_lock */);
1225     }
1226   } // leave critical region under Patching_lock
1227 
1228 #ifdef ASSERT
1229   if (is_osr_method() && method() != NULL) {
1230     // Make sure osr nmethod is invalidated, i.e. not on the list
1231     bool found = method()->method_holder()->remove_osr_nmethod(this);
1232     assert(!found, "osr nmethod should have been invalidated");
1233   }
1234 #endif
1235 
1236   // When the nmethod becomes zombie it is no longer alive so the
1237   // dependencies must be flushed.  nmethods in the not_entrant
1238   // state will be flushed later when the transition to zombie
1239   // happens or they get unloaded.
1240   if (state == zombie) {
1241     {
1242       // Flushing dependencies must be done before any possible
1243       // safepoint can sneak in, otherwise the oops used by the
1244       // dependency logic could have become stale.
1245       MutexLockerEx mu(CodeCache_lock, Mutex::_no_safepoint_check_flag);
1246       if (nmethod_needs_unregister) {
1247         Universe::heap()->unregister_nmethod(this);
1248       }
1249       flush_dependencies(NULL);
1250     }
1251 
1252     // zombie only - if a JVMTI agent has enabled the CompiledMethodUnload
1253     // event and it hasn't already been reported for this nmethod then
1254     // report it now. The event may have been reported earlier if the GC
1255     // marked it for unloading). JvmtiDeferredEventQueue support means
1256     // we no longer go to a safepoint here.
1257     post_compiled_method_unload();
1258 
1259 #ifdef ASSERT
1260     // It's no longer safe to access the oops section since zombie
1261     // nmethods aren't scanned for GC.
1262     _oops_are_stale = true;
1263 #endif
1264      // the Method may be reclaimed by class unloading now that the
1265      // nmethod is in zombie state
1266     set_method(NULL);
1267   } else {
1268     assert(state == not_entrant, "other cases may need to be handled differently");
1269   }
1270 
1271   if (TraceCreateZombies) {
1272     ResourceMark m;
1273     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");
1274   }
1275 
1276   NMethodSweeper::report_state_change(this);
1277   return true;
1278 }
1279 
1280 void nmethod::flush() {
1281   // Note that there are no valid oops in the nmethod anymore.
1282   assert(!is_osr_method() || is_unloaded() || is_zombie(),
1283          "osr nmethod must be unloaded or zombie before flushing");
1284   assert(is_zombie() || is_osr_method(), "must be a zombie method");
1285   assert (!is_locked_by_vm(), "locked methods shouldn't be flushed");
1286   assert_locked_or_safepoint(CodeCache_lock);
1287 
1288   // completely deallocate this method
1289   Events::log(JavaThread::current(), "flushing nmethod " INTPTR_FORMAT, p2i(this));
1290   if (PrintMethodFlushing) {
1291     tty->print_cr("*flushing %s nmethod %3d/" INTPTR_FORMAT ". Live blobs:" UINT32_FORMAT
1292                   "/Free CodeCache:" SIZE_FORMAT "Kb",
1293                   is_osr_method() ? "osr" : "",_compile_id, p2i(this), CodeCache::blob_count(),
1294                   CodeCache::unallocated_capacity(CodeCache::get_code_blob_type(this))/1024);
1295   }
1296 
1297   // We need to deallocate any ExceptionCache data.
1298   // Note that we do not need to grab the nmethod lock for this, it
1299   // better be thread safe if we're disposing of it!
1300   ExceptionCache* ec = exception_cache();
1301   set_exception_cache(NULL);
1302   while(ec != NULL) {
1303     ExceptionCache* next = ec->next();
1304     delete ec;
1305     ec = next;
1306   }
1307 
1308   if (on_scavenge_root_list()) {
1309     CodeCache::drop_scavenge_root_nmethod(this);
1310   }
1311 
1312 #if INCLUDE_JVMCI
1313   assert(_jvmci_installed_code == NULL, "should have been nulled out when transitioned to zombie");
1314   assert(_speculation_log == NULL, "should have been nulled out when transitioned to zombie");
1315 #endif
1316 
1317   CodeBlob::flush();
1318   CodeCache::free(this);
1319 }
1320 
1321 //
1322 // Notify all classes this nmethod is dependent on that it is no
1323 // longer dependent. This should only be called in two situations.
1324 // First, when a nmethod transitions to a zombie all dependents need
1325 // to be clear.  Since zombification happens at a safepoint there's no
1326 // synchronization issues.  The second place is a little more tricky.
1327 // During phase 1 of mark sweep class unloading may happen and as a
1328 // result some nmethods may get unloaded.  In this case the flushing
1329 // of dependencies must happen during phase 1 since after GC any
1330 // dependencies in the unloaded nmethod won't be updated, so
1331 // traversing the dependency information in unsafe.  In that case this
1332 // function is called with a non-NULL argument and this function only
1333 // notifies instanceKlasses that are reachable
1334 
1335 void nmethod::flush_dependencies(BoolObjectClosure* is_alive) {
1336   assert_locked_or_safepoint(CodeCache_lock);
1337   assert(Universe::heap()->is_gc_active() == (is_alive != NULL),
1338   "is_alive is non-NULL if and only if we are called during GC");
1339   if (!has_flushed_dependencies()) {
1340     set_has_flushed_dependencies();
1341     for (Dependencies::DepStream deps(this); deps.next(); ) {
1342       if (deps.type() == Dependencies::call_site_target_value) {
1343         // CallSite dependencies are managed on per-CallSite instance basis.
1344         oop call_site = deps.argument_oop(0);
1345         MethodHandles::remove_dependent_nmethod(call_site, this);
1346       } else {
1347         Klass* klass = deps.context_type();
1348         if (klass == NULL) {
1349           continue;  // ignore things like evol_method
1350         }
1351         // During GC the is_alive closure is non-NULL, and is used to
1352         // determine liveness of dependees that need to be updated.
1353         if (is_alive == NULL || klass->is_loader_alive(is_alive)) {
1354           // The GC defers deletion of this entry, since there might be multiple threads
1355           // iterating over the _dependencies graph. Other call paths are single-threaded
1356           // and may delete it immediately.
1357           bool delete_immediately = is_alive == NULL;
1358           InstanceKlass::cast(klass)->remove_dependent_nmethod(this, delete_immediately);
1359         }
1360       }
1361     }
1362   }
1363 }
1364 
1365 
1366 // If this oop is not live, the nmethod can be unloaded.
1367 bool nmethod::can_unload(BoolObjectClosure* is_alive, oop* root, bool unloading_occurred) {
1368   assert(root != NULL, "just checking");
1369   oop obj = *root;
1370   if (obj == NULL || is_alive->do_object_b(obj)) {
1371       return false;
1372   }
1373 
1374   // If ScavengeRootsInCode is true, an nmethod might be unloaded
1375   // simply because one of its constant oops has gone dead.
1376   // No actual classes need to be unloaded in order for this to occur.
1377   assert(unloading_occurred || ScavengeRootsInCode, "Inconsistency in unloading");
1378   make_unloaded(is_alive, obj);
1379   return true;
1380 }
1381 
1382 // ------------------------------------------------------------------
1383 // post_compiled_method_load_event
1384 // new method for install_code() path
1385 // Transfer information from compilation to jvmti
1386 void nmethod::post_compiled_method_load_event() {
1387 
1388   Method* moop = method();
1389   HOTSPOT_COMPILED_METHOD_LOAD(
1390       (char *) moop->klass_name()->bytes(),
1391       moop->klass_name()->utf8_length(),
1392       (char *) moop->name()->bytes(),
1393       moop->name()->utf8_length(),
1394       (char *) moop->signature()->bytes(),
1395       moop->signature()->utf8_length(),
1396       insts_begin(), insts_size());
1397 
1398   if (JvmtiExport::should_post_compiled_method_load() ||
1399       JvmtiExport::should_post_compiled_method_unload()) {
1400     get_and_cache_jmethod_id();
1401   }
1402 
1403   if (JvmtiExport::should_post_compiled_method_load()) {
1404     // Let the Service thread (which is a real Java thread) post the event
1405     MutexLockerEx ml(Service_lock, Mutex::_no_safepoint_check_flag);
1406     JvmtiDeferredEventQueue::enqueue(
1407       JvmtiDeferredEvent::compiled_method_load_event(this));
1408   }
1409 }
1410 
1411 jmethodID nmethod::get_and_cache_jmethod_id() {
1412   if (_jmethod_id == NULL) {
1413     // Cache the jmethod_id since it can no longer be looked up once the
1414     // method itself has been marked for unloading.
1415     _jmethod_id = method()->jmethod_id();
1416   }
1417   return _jmethod_id;
1418 }
1419 
1420 void nmethod::post_compiled_method_unload() {
1421   if (unload_reported()) {
1422     // During unloading we transition to unloaded and then to zombie
1423     // and the unloading is reported during the first transition.
1424     return;
1425   }
1426 
1427   assert(_method != NULL && !is_unloaded(), "just checking");
1428   DTRACE_METHOD_UNLOAD_PROBE(method());
1429 
1430   // If a JVMTI agent has enabled the CompiledMethodUnload event then
1431   // post the event. Sometime later this nmethod will be made a zombie
1432   // by the sweeper but the Method* will not be valid at that point.
1433   // If the _jmethod_id is null then no load event was ever requested
1434   // so don't bother posting the unload.  The main reason for this is
1435   // that the jmethodID is a weak reference to the Method* so if
1436   // it's being unloaded there's no way to look it up since the weak
1437   // ref will have been cleared.
1438   if (_jmethod_id != NULL && JvmtiExport::should_post_compiled_method_unload()) {
1439     assert(!unload_reported(), "already unloaded");
1440     JvmtiDeferredEvent event =
1441       JvmtiDeferredEvent::compiled_method_unload_event(this,
1442           _jmethod_id, insts_begin());
1443     MutexLockerEx ml(Service_lock, Mutex::_no_safepoint_check_flag);
1444     JvmtiDeferredEventQueue::enqueue(event);
1445   }
1446 
1447   // The JVMTI CompiledMethodUnload event can be enabled or disabled at
1448   // any time. As the nmethod is being unloaded now we mark it has
1449   // having the unload event reported - this will ensure that we don't
1450   // attempt to report the event in the unlikely scenario where the
1451   // event is enabled at the time the nmethod is made a zombie.
1452   set_unload_reported();
1453 }
1454 
1455 bool nmethod::unload_if_dead_at(RelocIterator* iter_at_oop, BoolObjectClosure *is_alive, bool unloading_occurred) {
1456   assert(iter_at_oop->type() == relocInfo::oop_type, "Wrong relocation type");
1457 
1458   oop_Relocation* r = iter_at_oop->oop_reloc();
1459   // Traverse those oops directly embedded in the code.
1460   // Other oops (oop_index>0) are seen as part of scopes_oops.
1461   assert(1 == (r->oop_is_immediate()) +
1462          (r->oop_addr() >= oops_begin() && r->oop_addr() < oops_end()),
1463          "oop must be found in exactly one place");
1464   if (r->oop_is_immediate() && r->oop_value() != NULL) {
1465     // Unload this nmethod if the oop is dead.
1466     if (can_unload(is_alive, r->oop_addr(), unloading_occurred)) {
1467       return true;;
1468     }
1469   }
1470 
1471   return false;
1472 }
1473 
1474 bool nmethod::do_unloading_scopes(BoolObjectClosure* is_alive, bool unloading_occurred) {
1475   // Scopes
1476   for (oop* p = oops_begin(); p < oops_end(); p++) {
1477     if (*p == Universe::non_oop_word())  continue;  // skip non-oops
1478     if (can_unload(is_alive, p, unloading_occurred)) {
1479       return true;
1480     }
1481   }
1482   return false;
1483 }
1484 
1485 bool nmethod::do_unloading_oops(address low_boundary, BoolObjectClosure* is_alive, bool unloading_occurred) {
1486   // Compiled code
1487   {
1488   RelocIterator iter(this, low_boundary);
1489   while (iter.next()) {
1490     if (iter.type() == relocInfo::oop_type) {
1491       if (unload_if_dead_at(&iter, is_alive, unloading_occurred)) {
1492         return true;
1493       }
1494     }
1495   }
1496   }
1497 
1498   return do_unloading_scopes(is_alive, unloading_occurred);
1499 }
1500 
1501 #if INCLUDE_JVMCI
1502 bool nmethod::do_unloading_jvmci(BoolObjectClosure* is_alive, bool unloading_occurred) {
1503   if (_jvmci_installed_code != NULL) {
1504     if (JNIHandles::is_global_weak_cleared(_jvmci_installed_code)) {
1505       if (_jvmci_installed_code_triggers_unloading) {
1506         // jweak reference processing has already cleared the referent
1507         make_unloaded(is_alive, NULL);
1508         return true;
1509       } else {
1510         clear_jvmci_installed_code();
1511       }
1512     }
1513   }
1514   return false;
1515 }
1516 #endif
1517 
1518 // Iterate over metadata calling this function.   Used by RedefineClasses
1519 void nmethod::metadata_do(void f(Metadata*)) {
1520   address low_boundary = verified_entry_point();
1521   if (is_not_entrant()) {
1522     low_boundary += NativeJump::instruction_size;
1523     // %%% Note:  On SPARC we patch only a 4-byte trap, not a full NativeJump.
1524     // (See comment above.)
1525   }
1526   {
1527     // Visit all immediate references that are embedded in the instruction stream.
1528     RelocIterator iter(this, low_boundary);
1529     while (iter.next()) {
1530       if (iter.type() == relocInfo::metadata_type ) {
1531         metadata_Relocation* r = iter.metadata_reloc();
1532         // In this metadata, we must only follow those metadatas directly embedded in
1533         // the code.  Other metadatas (oop_index>0) are seen as part of
1534         // the metadata section below.
1535         assert(1 == (r->metadata_is_immediate()) +
1536                (r->metadata_addr() >= metadata_begin() && r->metadata_addr() < metadata_end()),
1537                "metadata must be found in exactly one place");
1538         if (r->metadata_is_immediate() && r->metadata_value() != NULL) {
1539           Metadata* md = r->metadata_value();
1540           if (md != _method) f(md);
1541         }
1542       } else if (iter.type() == relocInfo::virtual_call_type) {
1543         // Check compiledIC holders associated with this nmethod
1544         CompiledIC *ic = CompiledIC_at(&iter);
1545         if (ic->is_icholder_call()) {
1546           CompiledICHolder* cichk = ic->cached_icholder();
1547           f(cichk->holder_method());
1548           f(cichk->holder_klass());
1549         } else {
1550           Metadata* ic_oop = ic->cached_metadata();
1551           if (ic_oop != NULL) {
1552             f(ic_oop);
1553           }
1554         }
1555       }
1556     }
1557   }
1558 
1559   // Visit the metadata section
1560   for (Metadata** p = metadata_begin(); p < metadata_end(); p++) {
1561     if (*p == Universe::non_oop_word() || *p == NULL)  continue;  // skip non-oops
1562     Metadata* md = *p;
1563     f(md);
1564   }
1565 
1566   // Visit metadata not embedded in the other places.
1567   if (_method != NULL) f(_method);
1568 }
1569 
1570 void nmethod::oops_do(OopClosure* f, bool allow_zombie) {
1571   // make sure the oops ready to receive visitors
1572   assert(allow_zombie || !is_zombie(), "should not call follow on zombie nmethod");
1573   assert(!is_unloaded(), "should not call follow on unloaded nmethod");
1574 
1575   // If the method is not entrant or zombie then a JMP is plastered over the
1576   // first few bytes.  If an oop in the old code was there, that oop
1577   // should not get GC'd.  Skip the first few bytes of oops on
1578   // not-entrant methods.
1579   address low_boundary = verified_entry_point();
1580   if (is_not_entrant()) {
1581     low_boundary += NativeJump::instruction_size;
1582     // %%% Note:  On SPARC we patch only a 4-byte trap, not a full NativeJump.
1583     // (See comment above.)
1584   }
1585 
1586   RelocIterator iter(this, low_boundary);
1587 
1588   while (iter.next()) {
1589     if (iter.type() == relocInfo::oop_type ) {
1590       oop_Relocation* r = iter.oop_reloc();
1591       // In this loop, we must only follow those oops directly embedded in
1592       // the code.  Other oops (oop_index>0) are seen as part of scopes_oops.
1593       assert(1 == (r->oop_is_immediate()) +
1594                    (r->oop_addr() >= oops_begin() && r->oop_addr() < oops_end()),
1595              "oop must be found in exactly one place");
1596       if (r->oop_is_immediate() && r->oop_value() != NULL) {
1597         f->do_oop(r->oop_addr());
1598       }
1599     }
1600   }
1601 
1602   // Scopes
1603   // This includes oop constants not inlined in the code stream.
1604   for (oop* p = oops_begin(); p < oops_end(); p++) {
1605     if (*p == Universe::non_oop_word())  continue;  // skip non-oops
1606     f->do_oop(p);
1607   }
1608 }
1609 
1610 #define NMETHOD_SENTINEL ((nmethod*)badAddress)
1611 
1612 nmethod* volatile nmethod::_oops_do_mark_nmethods;
1613 
1614 // An nmethod is "marked" if its _mark_link is set non-null.
1615 // Even if it is the end of the linked list, it will have a non-null link value,
1616 // as long as it is on the list.
1617 // This code must be MP safe, because it is used from parallel GC passes.
1618 bool nmethod::test_set_oops_do_mark() {
1619   assert(nmethod::oops_do_marking_is_active(), "oops_do_marking_prologue must be called");
1620   if (_oops_do_mark_link == NULL) {
1621     // Claim this nmethod for this thread to mark.
1622     if (Atomic::cmpxchg(NMETHOD_SENTINEL, &_oops_do_mark_link, (nmethod*)NULL) == NULL) {
1623       // Atomically append this nmethod (now claimed) to the head of the list:
1624       nmethod* observed_mark_nmethods = _oops_do_mark_nmethods;
1625       for (;;) {
1626         nmethod* required_mark_nmethods = observed_mark_nmethods;
1627         _oops_do_mark_link = required_mark_nmethods;
1628         observed_mark_nmethods =
1629           Atomic::cmpxchg(this, &_oops_do_mark_nmethods, required_mark_nmethods);
1630         if (observed_mark_nmethods == required_mark_nmethods)
1631           break;
1632       }
1633       // Mark was clear when we first saw this guy.
1634       if (TraceScavenge) { print_on(tty, "oops_do, mark"); }
1635       return false;
1636     }
1637   }
1638   // On fall through, another racing thread marked this nmethod before we did.
1639   return true;
1640 }
1641 
1642 void nmethod::oops_do_marking_prologue() {
1643   if (TraceScavenge) { tty->print_cr("[oops_do_marking_prologue"); }
1644   assert(_oops_do_mark_nmethods == NULL, "must not call oops_do_marking_prologue twice in a row");
1645   // We use cmpxchg instead of regular assignment here because the user
1646   // may fork a bunch of threads, and we need them all to see the same state.
1647   nmethod* observed = Atomic::cmpxchg(NMETHOD_SENTINEL, &_oops_do_mark_nmethods, (nmethod*)NULL);
1648   guarantee(observed == NULL, "no races in this sequential code");
1649 }
1650 
1651 void nmethod::oops_do_marking_epilogue() {
1652   assert(_oops_do_mark_nmethods != NULL, "must not call oops_do_marking_epilogue twice in a row");
1653   nmethod* cur = _oops_do_mark_nmethods;
1654   while (cur != NMETHOD_SENTINEL) {
1655     assert(cur != NULL, "not NULL-terminated");
1656     nmethod* next = cur->_oops_do_mark_link;
1657     cur->_oops_do_mark_link = NULL;
1658     DEBUG_ONLY(cur->verify_oop_relocations());
1659     NOT_PRODUCT(if (TraceScavenge)  cur->print_on(tty, "oops_do, unmark"));
1660     cur = next;
1661   }
1662   nmethod* required = _oops_do_mark_nmethods;
1663   nmethod* observed = Atomic::cmpxchg((nmethod*)NULL, &_oops_do_mark_nmethods, required);
1664   guarantee(observed == required, "no races in this sequential code");
1665   if (TraceScavenge) { tty->print_cr("oops_do_marking_epilogue]"); }
1666 }
1667 
1668 class DetectScavengeRoot: public OopClosure {
1669   bool     _detected_scavenge_root;
1670 public:
1671   DetectScavengeRoot() : _detected_scavenge_root(false)
1672   { NOT_PRODUCT(_print_nm = NULL); }
1673   bool detected_scavenge_root() { return _detected_scavenge_root; }
1674   virtual void do_oop(oop* p) {
1675     if ((*p) != NULL && (*p)->is_scavengable()) {
1676       NOT_PRODUCT(maybe_print(p));
1677       _detected_scavenge_root = true;
1678     }
1679   }
1680   virtual void do_oop(narrowOop* p) { ShouldNotReachHere(); }
1681 
1682 #ifndef PRODUCT
1683   nmethod* _print_nm;
1684   void maybe_print(oop* p) {
1685     if (_print_nm == NULL)  return;
1686     if (!_detected_scavenge_root)  _print_nm->print_on(tty, "new scavenge root");
1687     tty->print_cr("" PTR_FORMAT "[offset=%d] detected scavengable oop " PTR_FORMAT " (found at " PTR_FORMAT ")",
1688                   p2i(_print_nm), (int)((intptr_t)p - (intptr_t)_print_nm),
1689                   p2i(*p), p2i(p));
1690     (*p)->print();
1691   }
1692 #endif //PRODUCT
1693 };
1694 
1695 bool nmethod::detect_scavenge_root_oops() {
1696   DetectScavengeRoot detect_scavenge_root;
1697   NOT_PRODUCT(if (TraceScavenge)  detect_scavenge_root._print_nm = this);
1698   oops_do(&detect_scavenge_root);
1699   return detect_scavenge_root.detected_scavenge_root();
1700 }
1701 
1702 inline bool includes(void* p, void* from, void* to) {
1703   return from <= p && p < to;
1704 }
1705 
1706 
1707 void nmethod::copy_scopes_pcs(PcDesc* pcs, int count) {
1708   assert(count >= 2, "must be sentinel values, at least");
1709 
1710 #ifdef ASSERT
1711   // must be sorted and unique; we do a binary search in find_pc_desc()
1712   int prev_offset = pcs[0].pc_offset();
1713   assert(prev_offset == PcDesc::lower_offset_limit,
1714          "must start with a sentinel");
1715   for (int i = 1; i < count; i++) {
1716     int this_offset = pcs[i].pc_offset();
1717     assert(this_offset > prev_offset, "offsets must be sorted");
1718     prev_offset = this_offset;
1719   }
1720   assert(prev_offset == PcDesc::upper_offset_limit,
1721          "must end with a sentinel");
1722 #endif //ASSERT
1723 
1724   // Search for MethodHandle invokes and tag the nmethod.
1725   for (int i = 0; i < count; i++) {
1726     if (pcs[i].is_method_handle_invoke()) {
1727       set_has_method_handle_invokes(true);
1728       break;
1729     }
1730   }
1731   assert(has_method_handle_invokes() == (_deopt_mh_handler_begin != NULL), "must have deopt mh handler");
1732 
1733   int size = count * sizeof(PcDesc);
1734   assert(scopes_pcs_size() >= size, "oob");
1735   memcpy(scopes_pcs_begin(), pcs, size);
1736 
1737   // Adjust the final sentinel downward.
1738   PcDesc* last_pc = &scopes_pcs_begin()[count-1];
1739   assert(last_pc->pc_offset() == PcDesc::upper_offset_limit, "sanity");
1740   last_pc->set_pc_offset(content_size() + 1);
1741   for (; last_pc + 1 < scopes_pcs_end(); last_pc += 1) {
1742     // Fill any rounding gaps with copies of the last record.
1743     last_pc[1] = last_pc[0];
1744   }
1745   // The following assert could fail if sizeof(PcDesc) is not
1746   // an integral multiple of oopSize (the rounding term).
1747   // If it fails, change the logic to always allocate a multiple
1748   // of sizeof(PcDesc), and fill unused words with copies of *last_pc.
1749   assert(last_pc + 1 == scopes_pcs_end(), "must match exactly");
1750 }
1751 
1752 void nmethod::copy_scopes_data(u_char* buffer, int size) {
1753   assert(scopes_data_size() >= size, "oob");
1754   memcpy(scopes_data_begin(), buffer, size);
1755 }
1756 
1757 #ifdef ASSERT
1758 static PcDesc* linear_search(const PcDescSearch& search, int pc_offset, bool approximate) {
1759   PcDesc* lower = search.scopes_pcs_begin();
1760   PcDesc* upper = search.scopes_pcs_end();
1761   lower += 1; // exclude initial sentinel
1762   PcDesc* res = NULL;
1763   for (PcDesc* p = lower; p < upper; p++) {
1764     NOT_PRODUCT(--pc_nmethod_stats.pc_desc_tests);  // don't count this call to match_desc
1765     if (match_desc(p, pc_offset, approximate)) {
1766       if (res == NULL)
1767         res = p;
1768       else
1769         res = (PcDesc*) badAddress;
1770     }
1771   }
1772   return res;
1773 }
1774 #endif
1775 
1776 
1777 // Finds a PcDesc with real-pc equal to "pc"
1778 PcDesc* PcDescContainer::find_pc_desc_internal(address pc, bool approximate, const PcDescSearch& search) {
1779   address base_address = search.code_begin();
1780   if ((pc < base_address) ||
1781       (pc - base_address) >= (ptrdiff_t) PcDesc::upper_offset_limit) {
1782     return NULL;  // PC is wildly out of range
1783   }
1784   int pc_offset = (int) (pc - base_address);
1785 
1786   // Check the PcDesc cache if it contains the desired PcDesc
1787   // (This as an almost 100% hit rate.)
1788   PcDesc* res = _pc_desc_cache.find_pc_desc(pc_offset, approximate);
1789   if (res != NULL) {
1790     assert(res == linear_search(search, pc_offset, approximate), "cache ok");
1791     return res;
1792   }
1793 
1794   // Fallback algorithm: quasi-linear search for the PcDesc
1795   // Find the last pc_offset less than the given offset.
1796   // The successor must be the required match, if there is a match at all.
1797   // (Use a fixed radix to avoid expensive affine pointer arithmetic.)
1798   PcDesc* lower = search.scopes_pcs_begin();
1799   PcDesc* upper = search.scopes_pcs_end();
1800   upper -= 1; // exclude final sentinel
1801   if (lower >= upper)  return NULL;  // native method; no PcDescs at all
1802 
1803 #define assert_LU_OK \
1804   /* invariant on lower..upper during the following search: */ \
1805   assert(lower->pc_offset() <  pc_offset, "sanity"); \
1806   assert(upper->pc_offset() >= pc_offset, "sanity")
1807   assert_LU_OK;
1808 
1809   // Use the last successful return as a split point.
1810   PcDesc* mid = _pc_desc_cache.last_pc_desc();
1811   NOT_PRODUCT(++pc_nmethod_stats.pc_desc_searches);
1812   if (mid->pc_offset() < pc_offset) {
1813     lower = mid;
1814   } else {
1815     upper = mid;
1816   }
1817 
1818   // Take giant steps at first (4096, then 256, then 16, then 1)
1819   const int LOG2_RADIX = 4 /*smaller steps in debug mode:*/ debug_only(-1);
1820   const int RADIX = (1 << LOG2_RADIX);
1821   for (int step = (1 << (LOG2_RADIX*3)); step > 1; step >>= LOG2_RADIX) {
1822     while ((mid = lower + step) < upper) {
1823       assert_LU_OK;
1824       NOT_PRODUCT(++pc_nmethod_stats.pc_desc_searches);
1825       if (mid->pc_offset() < pc_offset) {
1826         lower = mid;
1827       } else {
1828         upper = mid;
1829         break;
1830       }
1831     }
1832     assert_LU_OK;
1833   }
1834 
1835   // Sneak up on the value with a linear search of length ~16.
1836   while (true) {
1837     assert_LU_OK;
1838     mid = lower + 1;
1839     NOT_PRODUCT(++pc_nmethod_stats.pc_desc_searches);
1840     if (mid->pc_offset() < pc_offset) {
1841       lower = mid;
1842     } else {
1843       upper = mid;
1844       break;
1845     }
1846   }
1847 #undef assert_LU_OK
1848 
1849   if (match_desc(upper, pc_offset, approximate)) {
1850     assert(upper == linear_search(search, pc_offset, approximate), "search ok");
1851     _pc_desc_cache.add_pc_desc(upper);
1852     return upper;
1853   } else {
1854     assert(NULL == linear_search(search, pc_offset, approximate), "search ok");
1855     return NULL;
1856   }
1857 }
1858 
1859 
1860 void nmethod::check_all_dependencies(DepChange& changes) {
1861   // Checked dependencies are allocated into this ResourceMark
1862   ResourceMark rm;
1863 
1864   // Turn off dependency tracing while actually testing dependencies.
1865   NOT_PRODUCT( FlagSetting fs(TraceDependencies, false) );
1866 
1867   typedef ResourceHashtable<DependencySignature, int, &DependencySignature::hash,
1868                             &DependencySignature::equals, 11027> DepTable;
1869 
1870   DepTable* table = new DepTable();
1871 
1872   // Iterate over live nmethods and check dependencies of all nmethods that are not
1873   // marked for deoptimization. A particular dependency is only checked once.
1874   NMethodIterator iter;
1875   while(iter.next()) {
1876     nmethod* nm = iter.method();
1877     // Only notify for live nmethods
1878     if (nm->is_alive() && !nm->is_marked_for_deoptimization()) {
1879       for (Dependencies::DepStream deps(nm); deps.next(); ) {
1880         // Construct abstraction of a dependency.
1881         DependencySignature* current_sig = new DependencySignature(deps);
1882 
1883         // Determine if dependency is already checked. table->put(...) returns
1884         // 'true' if the dependency is added (i.e., was not in the hashtable).
1885         if (table->put(*current_sig, 1)) {
1886           if (deps.check_dependency() != NULL) {
1887             // Dependency checking failed. Print out information about the failed
1888             // dependency and finally fail with an assert. We can fail here, since
1889             // dependency checking is never done in a product build.
1890             tty->print_cr("Failed dependency:");
1891             changes.print();
1892             nm->print();
1893             nm->print_dependencies();
1894             assert(false, "Should have been marked for deoptimization");
1895           }
1896         }
1897       }
1898     }
1899   }
1900 }
1901 
1902 bool nmethod::check_dependency_on(DepChange& changes) {
1903   // What has happened:
1904   // 1) a new class dependee has been added
1905   // 2) dependee and all its super classes have been marked
1906   bool found_check = false;  // set true if we are upset
1907   for (Dependencies::DepStream deps(this); deps.next(); ) {
1908     // Evaluate only relevant dependencies.
1909     if (deps.spot_check_dependency_at(changes) != NULL) {
1910       found_check = true;
1911       NOT_DEBUG(break);
1912     }
1913   }
1914   return found_check;
1915 }
1916 
1917 bool nmethod::is_evol_dependent_on(Klass* dependee) {
1918   InstanceKlass *dependee_ik = InstanceKlass::cast(dependee);
1919   Array<Method*>* dependee_methods = dependee_ik->methods();
1920   for (Dependencies::DepStream deps(this); deps.next(); ) {
1921     if (deps.type() == Dependencies::evol_method) {
1922       Method* method = deps.method_argument(0);
1923       for (int j = 0; j < dependee_methods->length(); j++) {
1924         if (dependee_methods->at(j) == method) {
1925           if (log_is_enabled(Debug, redefine, class, nmethod)) {
1926             ResourceMark rm;
1927             log_debug(redefine, class, nmethod)
1928               ("Found evol dependency of nmethod %s.%s(%s) compile_id=%d on method %s.%s(%s)",
1929                _method->method_holder()->external_name(),
1930                _method->name()->as_C_string(),
1931                _method->signature()->as_C_string(),
1932                compile_id(),
1933                method->method_holder()->external_name(),
1934                method->name()->as_C_string(),
1935                method->signature()->as_C_string());
1936           }
1937           if (TraceDependencies || LogCompilation)
1938             deps.log_dependency(dependee);
1939           return true;
1940         }
1941       }
1942     }
1943   }
1944   return false;
1945 }
1946 
1947 // Called from mark_for_deoptimization, when dependee is invalidated.
1948 bool nmethod::is_dependent_on_method(Method* dependee) {
1949   for (Dependencies::DepStream deps(this); deps.next(); ) {
1950     if (deps.type() != Dependencies::evol_method)
1951       continue;
1952     Method* method = deps.method_argument(0);
1953     if (method == dependee) return true;
1954   }
1955   return false;
1956 }
1957 
1958 
1959 bool nmethod::is_patchable_at(address instr_addr) {
1960   assert(insts_contains(instr_addr), "wrong nmethod used");
1961   if (is_zombie()) {
1962     // a zombie may never be patched
1963     return false;
1964   }
1965   return true;
1966 }
1967 
1968 
1969 address nmethod::continuation_for_implicit_exception(address pc) {
1970   // Exception happened outside inline-cache check code => we are inside
1971   // an active nmethod => use cpc to determine a return address
1972   int exception_offset = pc - code_begin();
1973   int cont_offset = ImplicitExceptionTable(this).at( exception_offset );
1974 #ifdef ASSERT
1975   if (cont_offset == 0) {
1976     Thread* thread = Thread::current();
1977     ResetNoHandleMark rnm; // Might be called from LEAF/QUICK ENTRY
1978     HandleMark hm(thread);
1979     ResourceMark rm(thread);
1980     CodeBlob* cb = CodeCache::find_blob(pc);
1981     assert(cb != NULL && cb == this, "");
1982     ttyLocker ttyl;
1983     tty->print_cr("implicit exception happened at " INTPTR_FORMAT, p2i(pc));
1984     print();
1985     method()->print_codes();
1986     print_code();
1987     print_pcs();
1988   }
1989 #endif
1990   if (cont_offset == 0) {
1991     // Let the normal error handling report the exception
1992     return NULL;
1993   }
1994   return code_begin() + cont_offset;
1995 }
1996 
1997 
1998 
1999 void nmethod_init() {
2000   // make sure you didn't forget to adjust the filler fields
2001   assert(sizeof(nmethod) % oopSize == 0, "nmethod size must be multiple of a word");
2002 }
2003 
2004 
2005 //-------------------------------------------------------------------------------------------
2006 
2007 
2008 // QQQ might we make this work from a frame??
2009 nmethodLocker::nmethodLocker(address pc) {
2010   CodeBlob* cb = CodeCache::find_blob(pc);
2011   guarantee(cb != NULL && cb->is_compiled(), "bad pc for a nmethod found");
2012   _nm = cb->as_compiled_method();
2013   lock_nmethod(_nm);
2014 }
2015 
2016 // Only JvmtiDeferredEvent::compiled_method_unload_event()
2017 // should pass zombie_ok == true.
2018 void nmethodLocker::lock_nmethod(CompiledMethod* cm, bool zombie_ok) {
2019   if (cm == NULL)  return;
2020   if (cm->is_aot()) return;  // FIXME: Revisit once _lock_count is added to aot_method
2021   nmethod* nm = cm->as_nmethod();
2022   Atomic::inc(&nm->_lock_count);
2023   assert(zombie_ok || !nm->is_zombie(), "cannot lock a zombie method");
2024 }
2025 
2026 void nmethodLocker::unlock_nmethod(CompiledMethod* cm) {
2027   if (cm == NULL)  return;
2028   if (cm->is_aot()) return;  // FIXME: Revisit once _lock_count is added to aot_method
2029   nmethod* nm = cm->as_nmethod();
2030   Atomic::dec(&nm->_lock_count);
2031   assert(nm->_lock_count >= 0, "unmatched nmethod lock/unlock");
2032 }
2033 
2034 
2035 // -----------------------------------------------------------------------------
2036 // Verification
2037 
2038 class VerifyOopsClosure: public OopClosure {
2039   nmethod* _nm;
2040   bool     _ok;
2041 public:
2042   VerifyOopsClosure(nmethod* nm) : _nm(nm), _ok(true) { }
2043   bool ok() { return _ok; }
2044   virtual void do_oop(oop* p) {
2045     if (oopDesc::is_oop_or_null(*p)) return;
2046     if (_ok) {
2047       _nm->print_nmethod(true);
2048       _ok = false;
2049     }
2050     tty->print_cr("*** non-oop " PTR_FORMAT " found at " PTR_FORMAT " (offset %d)",
2051                   p2i(*p), p2i(p), (int)((intptr_t)p - (intptr_t)_nm));
2052   }
2053   virtual void do_oop(narrowOop* p) { ShouldNotReachHere(); }
2054 };
2055 
2056 void nmethod::verify() {
2057 
2058   // Hmm. OSR methods can be deopted but not marked as zombie or not_entrant
2059   // seems odd.
2060 
2061   if (is_zombie() || is_not_entrant() || is_unloaded())
2062     return;
2063 
2064   // Make sure all the entry points are correctly aligned for patching.
2065   NativeJump::check_verified_entry_alignment(entry_point(), verified_entry_point());
2066 
2067   // assert(oopDesc::is_oop(method()), "must be valid");
2068 
2069   ResourceMark rm;
2070 
2071   if (!CodeCache::contains(this)) {
2072     fatal("nmethod at " INTPTR_FORMAT " not in zone", p2i(this));
2073   }
2074 
2075   if(is_native_method() )
2076     return;
2077 
2078   nmethod* nm = CodeCache::find_nmethod(verified_entry_point());
2079   if (nm != this) {
2080     fatal("findNMethod did not find this nmethod (" INTPTR_FORMAT ")", p2i(this));
2081   }
2082 
2083   for (PcDesc* p = scopes_pcs_begin(); p < scopes_pcs_end(); p++) {
2084     if (! p->verify(this)) {
2085       tty->print_cr("\t\tin nmethod at " INTPTR_FORMAT " (pcs)", p2i(this));
2086     }
2087   }
2088 
2089   VerifyOopsClosure voc(this);
2090   oops_do(&voc);
2091   assert(voc.ok(), "embedded oops must be OK");
2092   Universe::heap()->verify_nmethod(this);
2093 
2094   verify_scopes();
2095 }
2096 
2097 
2098 void nmethod::verify_interrupt_point(address call_site) {
2099   // Verify IC only when nmethod installation is finished.
2100   bool is_installed = (method()->code() == this) // nmethod is in state 'in_use' and installed
2101                       || !this->is_in_use();     // nmethod is installed, but not in 'in_use' state
2102   if (is_installed) {
2103     Thread *cur = Thread::current();
2104     if (CompiledIC_lock->owner() == cur ||
2105         ((cur->is_VM_thread() || cur->is_ConcurrentGC_thread()) &&
2106          SafepointSynchronize::is_at_safepoint())) {
2107       CompiledIC_at(this, call_site);
2108       CHECK_UNHANDLED_OOPS_ONLY(Thread::current()->clear_unhandled_oops());
2109     } else {
2110       MutexLocker ml_verify (CompiledIC_lock);
2111       CompiledIC_at(this, call_site);
2112     }
2113   }
2114 
2115   PcDesc* pd = pc_desc_at(nativeCall_at(call_site)->return_address());
2116   assert(pd != NULL, "PcDesc must exist");
2117   for (ScopeDesc* sd = new ScopeDesc(this, pd->scope_decode_offset(),
2118                                      pd->obj_decode_offset(), pd->should_reexecute(), pd->rethrow_exception(),
2119                                      pd->return_oop());
2120        !sd->is_top(); sd = sd->sender()) {
2121     sd->verify();
2122   }
2123 }
2124 
2125 void nmethod::verify_scopes() {
2126   if( !method() ) return;       // Runtime stubs have no scope
2127   if (method()->is_native()) return; // Ignore stub methods.
2128   // iterate through all interrupt point
2129   // and verify the debug information is valid.
2130   RelocIterator iter((nmethod*)this);
2131   while (iter.next()) {
2132     address stub = NULL;
2133     switch (iter.type()) {
2134       case relocInfo::virtual_call_type:
2135         verify_interrupt_point(iter.addr());
2136         break;
2137       case relocInfo::opt_virtual_call_type:
2138         stub = iter.opt_virtual_call_reloc()->static_stub(false);
2139         verify_interrupt_point(iter.addr());
2140         break;
2141       case relocInfo::static_call_type:
2142         stub = iter.static_call_reloc()->static_stub(false);
2143         //verify_interrupt_point(iter.addr());
2144         break;
2145       case relocInfo::runtime_call_type:
2146       case relocInfo::runtime_call_w_cp_type: {
2147         address destination = iter.reloc()->value();
2148         // Right now there is no way to find out which entries support
2149         // an interrupt point.  It would be nice if we had this
2150         // information in a table.
2151         break;
2152       }
2153       default:
2154         break;
2155     }
2156     assert(stub == NULL || stub_contains(stub), "static call stub outside stub section");
2157   }
2158 }
2159 
2160 
2161 // -----------------------------------------------------------------------------
2162 // Non-product code
2163 #ifndef PRODUCT
2164 
2165 class DebugScavengeRoot: public OopClosure {
2166   nmethod* _nm;
2167   bool     _ok;
2168 public:
2169   DebugScavengeRoot(nmethod* nm) : _nm(nm), _ok(true) { }
2170   bool ok() { return _ok; }
2171   virtual void do_oop(oop* p) {
2172     if ((*p) == NULL || !(*p)->is_scavengable())  return;
2173     if (_ok) {
2174       _nm->print_nmethod(true);
2175       _ok = false;
2176     }
2177     tty->print_cr("*** scavengable oop " PTR_FORMAT " found at " PTR_FORMAT " (offset %d)",
2178                   p2i(*p), p2i(p), (int)((intptr_t)p - (intptr_t)_nm));
2179     (*p)->print();
2180   }
2181   virtual void do_oop(narrowOop* p) { ShouldNotReachHere(); }
2182 };
2183 
2184 void nmethod::verify_scavenge_root_oops() {
2185   if (!on_scavenge_root_list()) {
2186     // Actually look inside, to verify the claim that it's clean.
2187     DebugScavengeRoot debug_scavenge_root(this);
2188     oops_do(&debug_scavenge_root);
2189     if (!debug_scavenge_root.ok())
2190       fatal("found an unadvertised bad scavengable oop in the code cache");
2191   }
2192   assert(scavenge_root_not_marked(), "");
2193 }
2194 
2195 #endif // PRODUCT
2196 
2197 // Printing operations
2198 
2199 void nmethod::print() const {
2200   ResourceMark rm;
2201   ttyLocker ttyl;   // keep the following output all in one block
2202 
2203   tty->print("Compiled method ");
2204 
2205   if (is_compiled_by_c1()) {
2206     tty->print("(c1) ");
2207   } else if (is_compiled_by_c2()) {
2208     tty->print("(c2) ");
2209   } else if (is_compiled_by_jvmci()) {
2210     tty->print("(JVMCI) ");
2211   } else {
2212     tty->print("(nm) ");
2213   }
2214 
2215   print_on(tty, NULL);
2216 
2217   if (WizardMode) {
2218     tty->print("((nmethod*) " INTPTR_FORMAT ") ", p2i(this));
2219     tty->print(" for method " INTPTR_FORMAT , p2i(method()));
2220     tty->print(" { ");
2221     tty->print_cr("%s ", state());
2222     if (on_scavenge_root_list())  tty->print("scavenge_root ");
2223     tty->print_cr("}:");
2224   }
2225   if (size              () > 0) tty->print_cr(" total in heap  [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
2226                                               p2i(this),
2227                                               p2i(this) + size(),
2228                                               size());
2229   if (relocation_size   () > 0) tty->print_cr(" relocation     [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
2230                                               p2i(relocation_begin()),
2231                                               p2i(relocation_end()),
2232                                               relocation_size());
2233   if (consts_size       () > 0) tty->print_cr(" constants      [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
2234                                               p2i(consts_begin()),
2235                                               p2i(consts_end()),
2236                                               consts_size());
2237   if (insts_size        () > 0) tty->print_cr(" main code      [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
2238                                               p2i(insts_begin()),
2239                                               p2i(insts_end()),
2240                                               insts_size());
2241   if (stub_size         () > 0) tty->print_cr(" stub code      [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
2242                                               p2i(stub_begin()),
2243                                               p2i(stub_end()),
2244                                               stub_size());
2245   if (oops_size         () > 0) tty->print_cr(" oops           [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
2246                                               p2i(oops_begin()),
2247                                               p2i(oops_end()),
2248                                               oops_size());
2249   if (metadata_size      () > 0) tty->print_cr(" metadata       [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
2250                                               p2i(metadata_begin()),
2251                                               p2i(metadata_end()),
2252                                               metadata_size());
2253   if (scopes_data_size  () > 0) tty->print_cr(" scopes data    [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
2254                                               p2i(scopes_data_begin()),
2255                                               p2i(scopes_data_end()),
2256                                               scopes_data_size());
2257   if (scopes_pcs_size   () > 0) tty->print_cr(" scopes pcs     [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
2258                                               p2i(scopes_pcs_begin()),
2259                                               p2i(scopes_pcs_end()),
2260                                               scopes_pcs_size());
2261   if (dependencies_size () > 0) tty->print_cr(" dependencies   [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
2262                                               p2i(dependencies_begin()),
2263                                               p2i(dependencies_end()),
2264                                               dependencies_size());
2265   if (handler_table_size() > 0) tty->print_cr(" handler table  [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
2266                                               p2i(handler_table_begin()),
2267                                               p2i(handler_table_end()),
2268                                               handler_table_size());
2269   if (nul_chk_table_size() > 0) tty->print_cr(" nul chk table  [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
2270                                               p2i(nul_chk_table_begin()),
2271                                               p2i(nul_chk_table_end()),
2272                                               nul_chk_table_size());
2273 }
2274 
2275 #ifndef PRODUCT
2276 
2277 void nmethod::print_scopes() {
2278   // Find the first pc desc for all scopes in the code and print it.
2279   ResourceMark rm;
2280   for (PcDesc* p = scopes_pcs_begin(); p < scopes_pcs_end(); p++) {
2281     if (p->scope_decode_offset() == DebugInformationRecorder::serialized_null)
2282       continue;
2283 
2284     ScopeDesc* sd = scope_desc_at(p->real_pc(this));
2285     while (sd != NULL) {
2286       sd->print_on(tty, p);
2287       sd = sd->sender();
2288     }
2289   }
2290 }
2291 
2292 void nmethod::print_dependencies() {
2293   ResourceMark rm;
2294   ttyLocker ttyl;   // keep the following output all in one block
2295   tty->print_cr("Dependencies:");
2296   for (Dependencies::DepStream deps(this); deps.next(); ) {
2297     deps.print_dependency();
2298     Klass* ctxk = deps.context_type();
2299     if (ctxk != NULL) {
2300       if (ctxk->is_instance_klass() && InstanceKlass::cast(ctxk)->is_dependent_nmethod(this)) {
2301         tty->print_cr("   [nmethod<=klass]%s", ctxk->external_name());
2302       }
2303     }
2304     deps.log_dependency();  // put it into the xml log also
2305   }
2306 }
2307 
2308 
2309 void nmethod::print_relocations() {
2310   ResourceMark m;       // in case methods get printed via the debugger
2311   tty->print_cr("relocations:");
2312   RelocIterator iter(this);
2313   iter.print();
2314 }
2315 
2316 
2317 void nmethod::print_pcs() {
2318   ResourceMark m;       // in case methods get printed via debugger
2319   tty->print_cr("pc-bytecode offsets:");
2320   for (PcDesc* p = scopes_pcs_begin(); p < scopes_pcs_end(); p++) {
2321     p->print(this);
2322   }
2323 }
2324 
2325 void nmethod::print_recorded_oops() {
2326   tty->print_cr("Recorded oops:");
2327   for (int i = 0; i < oops_count(); i++) {
2328     oop o = oop_at(i);
2329     tty->print("#%3d: " INTPTR_FORMAT " ", i, p2i(o));
2330     if (o == (oop)Universe::non_oop_word()) {
2331       tty->print("non-oop word");
2332     } else {
2333       o->print_value();
2334     }
2335     tty->cr();
2336   }
2337 }
2338 
2339 void nmethod::print_recorded_metadata() {
2340   tty->print_cr("Recorded metadata:");
2341   for (int i = 0; i < metadata_count(); i++) {
2342     Metadata* m = metadata_at(i);
2343     tty->print("#%3d: " INTPTR_FORMAT " ", i, p2i(m));
2344     if (m == (Metadata*)Universe::non_oop_word()) {
2345       tty->print("non-metadata word");
2346     } else {
2347       m->print_value_on_maybe_null(tty);
2348     }
2349     tty->cr();
2350   }
2351 }
2352 
2353 #endif // PRODUCT
2354 
2355 const char* nmethod::reloc_string_for(u_char* begin, u_char* end) {
2356   RelocIterator iter(this, begin, end);
2357   bool have_one = false;
2358   while (iter.next()) {
2359     have_one = true;
2360     switch (iter.type()) {
2361         case relocInfo::none:                  return "no_reloc";
2362         case relocInfo::oop_type: {
2363           stringStream st;
2364           oop_Relocation* r = iter.oop_reloc();
2365           oop obj = r->oop_value();
2366           st.print("oop(");
2367           if (obj == NULL) st.print("NULL");
2368           else obj->print_value_on(&st);
2369           st.print(")");
2370           return st.as_string();
2371         }
2372         case relocInfo::metadata_type: {
2373           stringStream st;
2374           metadata_Relocation* r = iter.metadata_reloc();
2375           Metadata* obj = r->metadata_value();
2376           st.print("metadata(");
2377           if (obj == NULL) st.print("NULL");
2378           else obj->print_value_on(&st);
2379           st.print(")");
2380           return st.as_string();
2381         }
2382         case relocInfo::runtime_call_type:
2383         case relocInfo::runtime_call_w_cp_type: {
2384           stringStream st;
2385           st.print("runtime_call");
2386           CallRelocation* r = (CallRelocation*)iter.reloc();
2387           address dest = r->destination();
2388           CodeBlob* cb = CodeCache::find_blob(dest);
2389           if (cb != NULL) {
2390             st.print(" %s", cb->name());
2391           } else {
2392             ResourceMark rm;
2393             const int buflen = 1024;
2394             char* buf = NEW_RESOURCE_ARRAY(char, buflen);
2395             int offset;
2396             if (os::dll_address_to_function_name(dest, buf, buflen, &offset)) {
2397               st.print(" %s", buf);
2398               if (offset != 0) {
2399                 st.print("+%d", offset);
2400               }
2401             }
2402           }
2403           return st.as_string();
2404         }
2405         case relocInfo::virtual_call_type: {
2406           stringStream st;
2407           st.print_raw("virtual_call");
2408           virtual_call_Relocation* r = iter.virtual_call_reloc();
2409           Method* m = r->method_value();
2410           if (m != NULL) {
2411             assert(m->is_method(), "");
2412             m->print_short_name(&st);
2413           }
2414           return st.as_string();
2415         }
2416         case relocInfo::opt_virtual_call_type: {
2417           stringStream st;
2418           st.print_raw("optimized virtual_call");
2419           opt_virtual_call_Relocation* r = iter.opt_virtual_call_reloc();
2420           Method* m = r->method_value();
2421           if (m != NULL) {
2422             assert(m->is_method(), "");
2423             m->print_short_name(&st);
2424           }
2425           return st.as_string();
2426         }
2427         case relocInfo::static_call_type: {
2428           stringStream st;
2429           st.print_raw("static_call");
2430           static_call_Relocation* r = iter.static_call_reloc();
2431           Method* m = r->method_value();
2432           if (m != NULL) {
2433             assert(m->is_method(), "");
2434             m->print_short_name(&st);
2435           }
2436           return st.as_string();
2437         }
2438         case relocInfo::static_stub_type:      return "static_stub";
2439         case relocInfo::external_word_type:    return "external_word";
2440         case relocInfo::internal_word_type:    return "internal_word";
2441         case relocInfo::section_word_type:     return "section_word";
2442         case relocInfo::poll_type:             return "poll";
2443         case relocInfo::poll_return_type:      return "poll_return";
2444         case relocInfo::type_mask:             return "type_bit_mask";
2445 
2446         default:
2447           break;
2448     }
2449   }
2450   return have_one ? "other" : NULL;
2451 }
2452 
2453 // Return a the last scope in (begin..end]
2454 ScopeDesc* nmethod::scope_desc_in(address begin, address end) {
2455   PcDesc* p = pc_desc_near(begin+1);
2456   if (p != NULL && p->real_pc(this) <= end) {
2457     return new ScopeDesc(this, p->scope_decode_offset(),
2458                          p->obj_decode_offset(), p->should_reexecute(), p->rethrow_exception(),
2459                          p->return_oop());
2460   }
2461   return NULL;
2462 }
2463 
2464 void nmethod::print_nmethod_labels(outputStream* stream, address block_begin) const {
2465   if (block_begin == entry_point())             stream->print_cr("[Entry Point]");
2466   if (block_begin == verified_entry_point())    stream->print_cr("[Verified Entry Point]");
2467   if (JVMCI_ONLY(_exception_offset >= 0 &&) block_begin == exception_begin())         stream->print_cr("[Exception Handler]");
2468   if (block_begin == stub_begin())              stream->print_cr("[Stub Code]");
2469   if (JVMCI_ONLY(_deopt_handler_begin != NULL &&) block_begin == deopt_handler_begin())     stream->print_cr("[Deopt Handler Code]");
2470 
2471   if (has_method_handle_invokes())
2472     if (block_begin == deopt_mh_handler_begin())  stream->print_cr("[Deopt MH Handler Code]");
2473 
2474   if (block_begin == consts_begin())            stream->print_cr("[Constants]");
2475 
2476   if (block_begin == entry_point()) {
2477     methodHandle m = method();
2478     if (m.not_null()) {
2479       stream->print("  # ");
2480       m->print_value_on(stream);
2481       stream->cr();
2482     }
2483     if (m.not_null() && !is_osr_method()) {
2484       ResourceMark rm;
2485       int sizeargs = m->size_of_parameters();
2486       BasicType* sig_bt = NEW_RESOURCE_ARRAY(BasicType, sizeargs);
2487       VMRegPair* regs   = NEW_RESOURCE_ARRAY(VMRegPair, sizeargs);
2488       {
2489         int sig_index = 0;
2490         if (!m->is_static())
2491           sig_bt[sig_index++] = T_OBJECT; // 'this'
2492         for (SignatureStream ss(m->signature()); !ss.at_return_type(); ss.next()) {
2493           BasicType t = ss.type();
2494           sig_bt[sig_index++] = t;
2495           if (type2size[t] == 2) {
2496             sig_bt[sig_index++] = T_VOID;
2497           } else {
2498             assert(type2size[t] == 1, "size is 1 or 2");
2499           }
2500         }
2501         assert(sig_index == sizeargs, "");
2502       }
2503       const char* spname = "sp"; // make arch-specific?
2504       intptr_t out_preserve = SharedRuntime::java_calling_convention(sig_bt, regs, sizeargs, false);
2505       int stack_slot_offset = this->frame_size() * wordSize;
2506       int tab1 = 14, tab2 = 24;
2507       int sig_index = 0;
2508       int arg_index = (m->is_static() ? 0 : -1);
2509       bool did_old_sp = false;
2510       for (SignatureStream ss(m->signature()); !ss.at_return_type(); ) {
2511         bool at_this = (arg_index == -1);
2512         bool at_old_sp = false;
2513         BasicType t = (at_this ? T_OBJECT : ss.type());
2514         assert(t == sig_bt[sig_index], "sigs in sync");
2515         if (at_this)
2516           stream->print("  # this: ");
2517         else
2518           stream->print("  # parm%d: ", arg_index);
2519         stream->move_to(tab1);
2520         VMReg fst = regs[sig_index].first();
2521         VMReg snd = regs[sig_index].second();
2522         if (fst->is_reg()) {
2523           stream->print("%s", fst->name());
2524           if (snd->is_valid())  {
2525             stream->print(":%s", snd->name());
2526           }
2527         } else if (fst->is_stack()) {
2528           int offset = fst->reg2stack() * VMRegImpl::stack_slot_size + stack_slot_offset;
2529           if (offset == stack_slot_offset)  at_old_sp = true;
2530           stream->print("[%s+0x%x]", spname, offset);
2531         } else {
2532           stream->print("reg%d:%d??", (int)(intptr_t)fst, (int)(intptr_t)snd);
2533         }
2534         stream->print(" ");
2535         stream->move_to(tab2);
2536         stream->print("= ");
2537         if (at_this) {
2538           m->method_holder()->print_value_on(stream);
2539         } else {
2540           bool did_name = false;
2541           if (!at_this && ss.is_object()) {
2542             Symbol* name = ss.as_symbol_or_null();
2543             if (name != NULL) {
2544               name->print_value_on(stream);
2545               did_name = true;
2546             }
2547           }
2548           if (!did_name)
2549             stream->print("%s", type2name(t));
2550         }
2551         if (at_old_sp) {
2552           stream->print("  (%s of caller)", spname);
2553           did_old_sp = true;
2554         }
2555         stream->cr();
2556         sig_index += type2size[t];
2557         arg_index += 1;
2558         if (!at_this)  ss.next();
2559       }
2560       if (!did_old_sp) {
2561         stream->print("  # ");
2562         stream->move_to(tab1);
2563         stream->print("[%s+0x%x]", spname, stack_slot_offset);
2564         stream->print("  (%s of caller)", spname);
2565         stream->cr();
2566       }
2567     }
2568   }
2569 }
2570 
2571 void nmethod::print_code_comment_on(outputStream* st, int column, u_char* begin, u_char* end) {
2572   // First, find an oopmap in (begin, end].
2573   // We use the odd half-closed interval so that oop maps and scope descs
2574   // which are tied to the byte after a call are printed with the call itself.
2575   address base = code_begin();
2576   ImmutableOopMapSet* oms = oop_maps();
2577   if (oms != NULL) {
2578     for (int i = 0, imax = oms->count(); i < imax; i++) {
2579       const ImmutableOopMapPair* pair = oms->pair_at(i);
2580       const ImmutableOopMap* om = pair->get_from(oms);
2581       address pc = base + pair->pc_offset();
2582       if (pc > begin) {
2583         if (pc <= end) {
2584           st->move_to(column);
2585           st->print("; ");
2586           om->print_on(st);
2587         }
2588         break;
2589       }
2590     }
2591   }
2592 
2593   // Print any debug info present at this pc.
2594   ScopeDesc* sd  = scope_desc_in(begin, end);
2595   if (sd != NULL) {
2596     st->move_to(column);
2597     if (sd->bci() == SynchronizationEntryBCI) {
2598       st->print(";*synchronization entry");
2599     } else {
2600       if (sd->method() == NULL) {
2601         st->print("method is NULL");
2602       } else if (sd->method()->is_native()) {
2603         st->print("method is native");
2604       } else {
2605         Bytecodes::Code bc = sd->method()->java_code_at(sd->bci());
2606         st->print(";*%s", Bytecodes::name(bc));
2607         switch (bc) {
2608         case Bytecodes::_invokevirtual:
2609         case Bytecodes::_invokespecial:
2610         case Bytecodes::_invokestatic:
2611         case Bytecodes::_invokeinterface:
2612           {
2613             Bytecode_invoke invoke(sd->method(), sd->bci());
2614             st->print(" ");
2615             if (invoke.name() != NULL)
2616               invoke.name()->print_symbol_on(st);
2617             else
2618               st->print("<UNKNOWN>");
2619             break;
2620           }
2621         case Bytecodes::_getfield:
2622         case Bytecodes::_putfield:
2623         case Bytecodes::_getstatic:
2624         case Bytecodes::_putstatic:
2625           {
2626             Bytecode_field field(sd->method(), sd->bci());
2627             st->print(" ");
2628             if (field.name() != NULL)
2629               field.name()->print_symbol_on(st);
2630             else
2631               st->print("<UNKNOWN>");
2632           }
2633         default:
2634           break;
2635         }
2636       }
2637       st->print(" {reexecute=%d rethrow=%d return_oop=%d}", sd->should_reexecute(), sd->rethrow_exception(), sd->return_oop());
2638     }
2639 
2640     // Print all scopes
2641     for (;sd != NULL; sd = sd->sender()) {
2642       st->move_to(column);
2643       st->print("; -");
2644       if (sd->method() == NULL) {
2645         st->print("method is NULL");
2646       } else {
2647         sd->method()->print_short_name(st);
2648       }
2649       int lineno = sd->method()->line_number_from_bci(sd->bci());
2650       if (lineno != -1) {
2651         st->print("@%d (line %d)", sd->bci(), lineno);
2652       } else {
2653         st->print("@%d", sd->bci());
2654       }
2655       st->cr();
2656     }
2657   }
2658 
2659   // Print relocation information
2660   const char* str = reloc_string_for(begin, end);
2661   if (str != NULL) {
2662     if (sd != NULL) st->cr();
2663     st->move_to(column);
2664     st->print(";   {%s}", str);
2665   }
2666   int cont_offset = ImplicitExceptionTable(this).at(begin - code_begin());
2667   if (cont_offset != 0) {
2668     st->move_to(column);
2669     st->print("; implicit exception: dispatches to " INTPTR_FORMAT, p2i(code_begin() + cont_offset));
2670   }
2671 
2672 }
2673 
2674 class DirectNativeCallWrapper: public NativeCallWrapper {
2675 private:
2676   NativeCall* _call;
2677 
2678 public:
2679   DirectNativeCallWrapper(NativeCall* call) : _call(call) {}
2680 
2681   virtual address destination() const { return _call->destination(); }
2682   virtual address instruction_address() const { return _call->instruction_address(); }
2683   virtual address next_instruction_address() const { return _call->next_instruction_address(); }
2684   virtual address return_address() const { return _call->return_address(); }
2685 
2686   virtual address get_resolve_call_stub(bool is_optimized) const {
2687     if (is_optimized) {
2688       return SharedRuntime::get_resolve_opt_virtual_call_stub();
2689     }
2690     return SharedRuntime::get_resolve_virtual_call_stub();
2691   }
2692 
2693   virtual void set_destination_mt_safe(address dest) {
2694 #if INCLUDE_AOT
2695     if (UseAOT) {
2696       CodeBlob* callee = CodeCache::find_blob(dest);
2697       CompiledMethod* cm = callee->as_compiled_method_or_null();
2698       if (cm != NULL && cm->is_far_code()) {
2699         // Temporary fix, see JDK-8143106
2700         CompiledDirectStaticCall* csc = CompiledDirectStaticCall::at(instruction_address());
2701         csc->set_to_far(methodHandle(cm->method()), dest);
2702         return;
2703       }
2704     }
2705 #endif
2706     _call->set_destination_mt_safe(dest);
2707   }
2708 
2709   virtual void set_to_interpreted(const methodHandle& method, CompiledICInfo& info) {
2710     CompiledDirectStaticCall* csc = CompiledDirectStaticCall::at(instruction_address());
2711 #if INCLUDE_AOT
2712     if (info.to_aot()) {
2713       csc->set_to_far(method, info.entry());
2714     } else
2715 #endif
2716     {
2717       csc->set_to_interpreted(method, info.entry());
2718     }
2719   }
2720 
2721   virtual void verify() const {
2722     // make sure code pattern is actually a call imm32 instruction
2723     _call->verify();
2724     if (os::is_MP()) {
2725       _call->verify_alignment();
2726     }
2727   }
2728 
2729   virtual void verify_resolve_call(address dest) const {
2730     CodeBlob* db = CodeCache::find_blob_unsafe(dest);
2731     assert(!db->is_adapter_blob(), "must use stub!");
2732   }
2733 
2734   virtual bool is_call_to_interpreted(address dest) const {
2735     CodeBlob* cb = CodeCache::find_blob(_call->instruction_address());
2736     return cb->contains(dest);
2737   }
2738 
2739   virtual bool is_safe_for_patching() const { return false; }
2740 
2741   virtual NativeInstruction* get_load_instruction(virtual_call_Relocation* r) const {
2742     return nativeMovConstReg_at(r->cached_value());
2743   }
2744 
2745   virtual void *get_data(NativeInstruction* instruction) const {
2746     return (void*)((NativeMovConstReg*) instruction)->data();
2747   }
2748 
2749   virtual void set_data(NativeInstruction* instruction, intptr_t data) {
2750     ((NativeMovConstReg*) instruction)->set_data(data);
2751   }
2752 };
2753 
2754 NativeCallWrapper* nmethod::call_wrapper_at(address call) const {
2755   return new DirectNativeCallWrapper((NativeCall*) call);
2756 }
2757 
2758 NativeCallWrapper* nmethod::call_wrapper_before(address return_pc) const {
2759   return new DirectNativeCallWrapper(nativeCall_before(return_pc));
2760 }
2761 
2762 address nmethod::call_instruction_address(address pc) const {
2763   if (NativeCall::is_call_before(pc)) {
2764     NativeCall *ncall = nativeCall_before(pc);
2765     return ncall->instruction_address();
2766   }
2767   return NULL;
2768 }
2769 
2770 CompiledStaticCall* nmethod::compiledStaticCall_at(Relocation* call_site) const {
2771   return CompiledDirectStaticCall::at(call_site);
2772 }
2773 
2774 CompiledStaticCall* nmethod::compiledStaticCall_at(address call_site) const {
2775   return CompiledDirectStaticCall::at(call_site);
2776 }
2777 
2778 CompiledStaticCall* nmethod::compiledStaticCall_before(address return_addr) const {
2779   return CompiledDirectStaticCall::before(return_addr);
2780 }
2781 
2782 #ifndef PRODUCT
2783 
2784 void nmethod::print_value_on(outputStream* st) const {
2785   st->print("nmethod");
2786   print_on(st, NULL);
2787 }
2788 
2789 void nmethod::print_calls(outputStream* st) {
2790   RelocIterator iter(this);
2791   while (iter.next()) {
2792     switch (iter.type()) {
2793     case relocInfo::virtual_call_type:
2794     case relocInfo::opt_virtual_call_type: {
2795       VerifyMutexLocker mc(CompiledIC_lock);
2796       CompiledIC_at(&iter)->print();
2797       break;
2798     }
2799     case relocInfo::static_call_type:
2800       st->print_cr("Static call at " INTPTR_FORMAT, p2i(iter.reloc()->addr()));
2801       CompiledDirectStaticCall::at(iter.reloc())->print();
2802       break;
2803     default:
2804       break;
2805     }
2806   }
2807 }
2808 
2809 void nmethod::print_handler_table() {
2810   ExceptionHandlerTable(this).print();
2811 }
2812 
2813 void nmethod::print_nul_chk_table() {
2814   ImplicitExceptionTable(this).print(code_begin());
2815 }
2816 
2817 void nmethod::print_statistics() {
2818   ttyLocker ttyl;
2819   if (xtty != NULL)  xtty->head("statistics type='nmethod'");
2820   native_nmethod_stats.print_native_nmethod_stats();
2821 #ifdef COMPILER1
2822   c1_java_nmethod_stats.print_nmethod_stats("C1");
2823 #endif
2824 #ifdef COMPILER2
2825   c2_java_nmethod_stats.print_nmethod_stats("C2");
2826 #endif
2827 #if INCLUDE_JVMCI
2828   jvmci_java_nmethod_stats.print_nmethod_stats("JVMCI");
2829 #endif
2830   unknown_java_nmethod_stats.print_nmethod_stats("Unknown");
2831   DebugInformationRecorder::print_statistics();
2832 #ifndef PRODUCT
2833   pc_nmethod_stats.print_pc_stats();
2834 #endif
2835   Dependencies::print_statistics();
2836   if (xtty != NULL)  xtty->tail("statistics");
2837 }
2838 
2839 #endif // !PRODUCT
2840 
2841 #if INCLUDE_JVMCI
2842 void nmethod::clear_jvmci_installed_code() {
2843   assert_locked_or_safepoint(Patching_lock);
2844   if (_jvmci_installed_code != NULL) {
2845     JNIHandles::destroy_weak_global(_jvmci_installed_code);
2846     _jvmci_installed_code = NULL;
2847   }
2848 }
2849 
2850 void nmethod::clear_speculation_log() {
2851   assert_locked_or_safepoint(Patching_lock);
2852   if (_speculation_log != NULL) {
2853     JNIHandles::destroy_weak_global(_speculation_log);
2854     _speculation_log = NULL;
2855   }
2856 }
2857 
2858 void nmethod::maybe_invalidate_installed_code() {
2859   assert(Patching_lock->is_locked() ||
2860          SafepointSynchronize::is_at_safepoint(), "should be performed under a lock for consistency");
2861   oop installed_code = JNIHandles::resolve(_jvmci_installed_code);
2862   if (installed_code != NULL) {
2863     // Update the values in the InstalledCode instance if it still refers to this nmethod
2864     nmethod* nm = (nmethod*)InstalledCode::address(installed_code);
2865     if (nm == this) {
2866       if (!is_alive()) {
2867         // Break the link between nmethod and InstalledCode such that the nmethod
2868         // can subsequently be flushed safely.  The link must be maintained while
2869         // the method could have live activations since invalidateInstalledCode
2870         // might want to invalidate all existing activations.
2871         InstalledCode::set_address(installed_code, 0);
2872         InstalledCode::set_entryPoint(installed_code, 0);
2873       } else if (is_not_entrant()) {
2874         // Remove the entry point so any invocation will fail but keep
2875         // the address link around that so that existing activations can
2876         // be invalidated.
2877         InstalledCode::set_entryPoint(installed_code, 0);
2878       }
2879     }
2880   }
2881   if (!is_alive()) {
2882     // Clear these out after the nmethod has been unregistered and any
2883     // updates to the InstalledCode instance have been performed.
2884     clear_jvmci_installed_code();
2885     clear_speculation_log();
2886   }
2887 }
2888 
2889 void nmethod::invalidate_installed_code(Handle installedCode, TRAPS) {
2890   if (installedCode() == NULL) {
2891     THROW(vmSymbols::java_lang_NullPointerException());
2892   }
2893   jlong nativeMethod = InstalledCode::address(installedCode);
2894   nmethod* nm = (nmethod*)nativeMethod;
2895   if (nm == NULL) {
2896     // Nothing to do
2897     return;
2898   }
2899 
2900   nmethodLocker nml(nm);
2901 #ifdef ASSERT
2902   {
2903     MutexLockerEx pl(Patching_lock, Mutex::_no_safepoint_check_flag);
2904     // This relationship can only be checked safely under a lock
2905     assert(!nm->is_alive() || nm->jvmci_installed_code() == installedCode(), "sanity check");
2906   }
2907 #endif
2908 
2909   if (nm->is_alive()) {
2910     // Invalidating the InstalledCode means we want the nmethod
2911     // to be deoptimized.
2912     nm->mark_for_deoptimization();
2913     VM_Deoptimize op;
2914     VMThread::execute(&op);
2915   }
2916 
2917   // Multiple threads could reach this point so we now need to
2918   // lock and re-check the link to the nmethod so that only one
2919   // thread clears it.
2920   MutexLockerEx pl(Patching_lock, Mutex::_no_safepoint_check_flag);
2921   if (InstalledCode::address(installedCode) == nativeMethod) {
2922       InstalledCode::set_address(installedCode, 0);
2923   }
2924 }
2925 
2926 oop nmethod::jvmci_installed_code() {
2927   return JNIHandles::resolve(_jvmci_installed_code);
2928 }
2929 
2930 oop nmethod::speculation_log() {
2931   return JNIHandles::resolve(_speculation_log);
2932 }
2933 
2934 char* nmethod::jvmci_installed_code_name(char* buf, size_t buflen) {
2935   if (!this->is_compiled_by_jvmci()) {
2936     return NULL;
2937   }
2938   oop installed_code = JNIHandles::resolve(_jvmci_installed_code);
2939   if (installed_code != NULL) {
2940     oop installed_code_name = NULL;
2941     if (installed_code->is_a(InstalledCode::klass())) {
2942       installed_code_name = InstalledCode::name(installed_code);
2943     }
2944     if (installed_code_name != NULL) {
2945       return java_lang_String::as_utf8_string(installed_code_name, buf, (int)buflen);
2946     }
2947   }
2948   return NULL;
2949 }
2950 #endif