rev 47445 : 8171853: Remove Shark compiler

   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 #endif
 413 }
 414 
 415 nmethod* nmethod::new_native_nmethod(const methodHandle& method,
 416   int compile_id,
 417   CodeBuffer *code_buffer,
 418   int vep_offset,
 419   int frame_complete,
 420   int frame_size,
 421   ByteSize basic_lock_owner_sp_offset,
 422   ByteSize basic_lock_sp_offset,
 423   OopMapSet* oop_maps) {
 424   code_buffer->finalize_oop_references(method);
 425   // create nmethod
 426   nmethod* nm = NULL;
 427   {
 428     MutexLockerEx mu(CodeCache_lock, Mutex::_no_safepoint_check_flag);
 429     int native_nmethod_size = CodeBlob::allocation_size(code_buffer, sizeof(nmethod));
 430     CodeOffsets offsets;
 431     offsets.set_value(CodeOffsets::Verified_Entry, vep_offset);
 432     offsets.set_value(CodeOffsets::Frame_Complete, frame_complete);
 433     nm = new (native_nmethod_size, CompLevel_none) nmethod(method(), compiler_none, native_nmethod_size,
 434                                             compile_id, &offsets,
 435                                             code_buffer, frame_size,
 436                                             basic_lock_owner_sp_offset,
 437                                             basic_lock_sp_offset, oop_maps);
 438     NOT_PRODUCT(if (nm != NULL)  native_nmethod_stats.note_native_nmethod(nm));
 439   }
 440   // verify nmethod
 441   debug_only(if (nm) nm->verify();) // might block
 442 
 443   if (nm != NULL) {
 444     nm->log_new_nmethod();
 445   }
 446 
 447   return nm;
 448 }
 449 
 450 nmethod* nmethod::new_nmethod(const methodHandle& method,
 451   int compile_id,
 452   int entry_bci,
 453   CodeOffsets* offsets,
 454   int orig_pc_offset,
 455   DebugInformationRecorder* debug_info,
 456   Dependencies* dependencies,
 457   CodeBuffer* code_buffer, int frame_size,
 458   OopMapSet* oop_maps,
 459   ExceptionHandlerTable* handler_table,
 460   ImplicitExceptionTable* nul_chk_table,
 461   AbstractCompiler* compiler,
 462   int comp_level
 463 #if INCLUDE_JVMCI
 464   , Handle installed_code,
 465   Handle speculationLog
 466 #endif
 467 )
 468 {
 469   assert(debug_info->oop_recorder() == code_buffer->oop_recorder(), "shared OR");
 470   code_buffer->finalize_oop_references(method);
 471   // create nmethod
 472   nmethod* nm = NULL;
 473   { MutexLockerEx mu(CodeCache_lock, Mutex::_no_safepoint_check_flag);
 474     int nmethod_size =
 475       CodeBlob::allocation_size(code_buffer, sizeof(nmethod))
 476       + adjust_pcs_size(debug_info->pcs_size())
 477       + align_up((int)dependencies->size_in_bytes(), oopSize)
 478       + align_up(handler_table->size_in_bytes()    , oopSize)
 479       + align_up(nul_chk_table->size_in_bytes()    , oopSize)
 480       + align_up(debug_info->data_size()           , oopSize);
 481 
 482     nm = new (nmethod_size, comp_level)
 483     nmethod(method(), compiler->type(), nmethod_size, compile_id, entry_bci, offsets,
 484             orig_pc_offset, debug_info, dependencies, code_buffer, frame_size,
 485             oop_maps,
 486             handler_table,
 487             nul_chk_table,
 488             compiler,
 489             comp_level
 490 #if INCLUDE_JVMCI
 491             , installed_code,
 492             speculationLog
 493 #endif
 494             );
 495 
 496     if (nm != NULL) {
 497       // To make dependency checking during class loading fast, record
 498       // the nmethod dependencies in the classes it is dependent on.
 499       // This allows the dependency checking code to simply walk the
 500       // class hierarchy above the loaded class, checking only nmethods
 501       // which are dependent on those classes.  The slow way is to
 502       // check every nmethod for dependencies which makes it linear in
 503       // the number of methods compiled.  For applications with a lot
 504       // classes the slow way is too slow.
 505       for (Dependencies::DepStream deps(nm); deps.next(); ) {
 506         if (deps.type() == Dependencies::call_site_target_value) {
 507           // CallSite dependencies are managed on per-CallSite instance basis.
 508           oop call_site = deps.argument_oop(0);
 509           MethodHandles::add_dependent_nmethod(call_site, nm);
 510         } else {
 511           Klass* klass = deps.context_type();
 512           if (klass == NULL) {
 513             continue;  // ignore things like evol_method
 514           }
 515           // record this nmethod as dependent on this klass
 516           InstanceKlass::cast(klass)->add_dependent_nmethod(nm);
 517         }
 518       }
 519       NOT_PRODUCT(if (nm != NULL)  note_java_nmethod(nm));
 520     }
 521   }
 522   // Do verification and logging outside CodeCache_lock.
 523   if (nm != NULL) {
 524     // Safepoints in nmethod::verify aren't allowed because nm hasn't been installed yet.
 525     DEBUG_ONLY(nm->verify();)
 526     nm->log_new_nmethod();
 527   }
 528   return nm;
 529 }
 530 
 531 // For native wrappers
 532 nmethod::nmethod(
 533   Method* method,
 534   CompilerType type,
 535   int nmethod_size,
 536   int compile_id,
 537   CodeOffsets* offsets,
 538   CodeBuffer* code_buffer,
 539   int frame_size,
 540   ByteSize basic_lock_owner_sp_offset,
 541   ByteSize basic_lock_sp_offset,
 542   OopMapSet* oop_maps )
 543   : CompiledMethod(method, "native nmethod", type, nmethod_size, sizeof(nmethod), code_buffer, offsets->value(CodeOffsets::Frame_Complete), frame_size, oop_maps, false),
 544   _native_receiver_sp_offset(basic_lock_owner_sp_offset),
 545   _native_basic_lock_sp_offset(basic_lock_sp_offset)
 546 {
 547   {
 548     int scopes_data_offset = 0;
 549     int deoptimize_offset       = 0;
 550     int deoptimize_mh_offset    = 0;
 551 
 552     debug_only(NoSafepointVerifier nsv;)
 553     assert_locked_or_safepoint(CodeCache_lock);
 554 
 555     init_defaults();
 556     _entry_bci               = InvocationEntryBci;
 557     // We have no exception handler or deopt handler make the
 558     // values something that will never match a pc like the nmethod vtable entry
 559     _exception_offset        = 0;
 560     _orig_pc_offset          = 0;
 561 
 562     _consts_offset           = data_offset();
 563     _stub_offset             = data_offset();
 564     _oops_offset             = data_offset();
 565     _metadata_offset         = _oops_offset         + align_up(code_buffer->total_oop_size(), oopSize);
 566     scopes_data_offset       = _metadata_offset     + align_up(code_buffer->total_metadata_size(), wordSize);
 567     _scopes_pcs_offset       = scopes_data_offset;
 568     _dependencies_offset     = _scopes_pcs_offset;
 569     _handler_table_offset    = _dependencies_offset;
 570     _nul_chk_table_offset    = _handler_table_offset;
 571     _nmethod_end_offset      = _nul_chk_table_offset;
 572     _compile_id              = compile_id;
 573     _comp_level              = CompLevel_none;
 574     _entry_point             = code_begin()          + offsets->value(CodeOffsets::Entry);
 575     _verified_entry_point    = code_begin()          + offsets->value(CodeOffsets::Verified_Entry);
 576     _osr_entry_point         = NULL;
 577     _exception_cache         = NULL;
 578     _pc_desc_container.reset_to(NULL);
 579     _hotness_counter         = NMethodSweeper::hotness_counter_reset_val();
 580 
 581     _scopes_data_begin = (address) this + scopes_data_offset;
 582     _deopt_handler_begin = (address) this + deoptimize_offset;
 583     _deopt_mh_handler_begin = (address) this + deoptimize_mh_offset;
 584 
 585     code_buffer->copy_code_and_locs_to(this);
 586     code_buffer->copy_values_to(this);
 587     if (ScavengeRootsInCode) {
 588       Universe::heap()->register_nmethod(this);
 589     }
 590     debug_only(Universe::heap()->verify_nmethod(this));
 591     CodeCache::commit(this);
 592   }
 593 
 594   if (PrintNativeNMethods || PrintDebugInfo || PrintRelocations || PrintDependencies) {
 595     ttyLocker ttyl;  // keep the following output all in one block
 596     // This output goes directly to the tty, not the compiler log.
 597     // To enable tools to match it up with the compilation activity,
 598     // be sure to tag this tty output with the compile ID.
 599     if (xtty != NULL) {
 600       xtty->begin_head("print_native_nmethod");
 601       xtty->method(_method);
 602       xtty->stamp();
 603       xtty->end_head(" address='" INTPTR_FORMAT "'", (intptr_t) this);
 604     }
 605     // print the header part first
 606     print();
 607     // then print the requested information
 608     if (PrintNativeNMethods) {
 609       print_code();
 610       if (oop_maps != NULL) {
 611         oop_maps->print();
 612       }
 613     }
 614     if (PrintRelocations) {
 615       print_relocations();
 616     }
 617     if (xtty != NULL) {
 618       xtty->tail("print_native_nmethod");
 619     }
 620   }
 621 }
 622 
 623 void* nmethod::operator new(size_t size, int nmethod_size, int comp_level) throw () {
 624   return CodeCache::allocate(nmethod_size, CodeCache::get_code_blob_type(comp_level));
 625 }
 626 
 627 nmethod::nmethod(
 628   Method* method,
 629   CompilerType type,
 630   int nmethod_size,
 631   int compile_id,
 632   int entry_bci,
 633   CodeOffsets* offsets,
 634   int orig_pc_offset,
 635   DebugInformationRecorder* debug_info,
 636   Dependencies* dependencies,
 637   CodeBuffer *code_buffer,
 638   int frame_size,
 639   OopMapSet* oop_maps,
 640   ExceptionHandlerTable* handler_table,
 641   ImplicitExceptionTable* nul_chk_table,
 642   AbstractCompiler* compiler,
 643   int comp_level
 644 #if INCLUDE_JVMCI
 645   , Handle installed_code,
 646   Handle speculation_log
 647 #endif
 648   )
 649   : CompiledMethod(method, "nmethod", type, nmethod_size, sizeof(nmethod), code_buffer, offsets->value(CodeOffsets::Frame_Complete), frame_size, oop_maps, false),
 650   _native_receiver_sp_offset(in_ByteSize(-1)),
 651   _native_basic_lock_sp_offset(in_ByteSize(-1))
 652 {
 653   assert(debug_info->oop_recorder() == code_buffer->oop_recorder(), "shared OR");
 654   {
 655     debug_only(NoSafepointVerifier nsv;)
 656     assert_locked_or_safepoint(CodeCache_lock);
 657 
 658     _deopt_handler_begin = (address) this;
 659     _deopt_mh_handler_begin = (address) this;
 660 
 661     init_defaults();
 662     _entry_bci               = entry_bci;
 663     _compile_id              = compile_id;
 664     _comp_level              = comp_level;
 665     _orig_pc_offset          = orig_pc_offset;
 666     _hotness_counter         = NMethodSweeper::hotness_counter_reset_val();
 667 
 668     // Section offsets
 669     _consts_offset           = content_offset()      + code_buffer->total_offset_of(code_buffer->consts());
 670     _stub_offset             = content_offset()      + code_buffer->total_offset_of(code_buffer->stubs());
 671     set_ctable_begin(header_begin() + _consts_offset);
 672 
 673 #if INCLUDE_JVMCI
 674     _jvmci_installed_code = installed_code();
 675     _speculation_log = (instanceOop)speculation_log();
 676 
 677     if (compiler->is_jvmci()) {
 678       // JVMCI might not produce any stub sections
 679       if (offsets->value(CodeOffsets::Exceptions) != -1) {
 680         _exception_offset        = code_offset()          + offsets->value(CodeOffsets::Exceptions);
 681       } else {
 682         _exception_offset = -1;
 683       }
 684       if (offsets->value(CodeOffsets::Deopt) != -1) {
 685         _deopt_handler_begin       = (address) this + code_offset()          + offsets->value(CodeOffsets::Deopt);
 686       } else {
 687         _deopt_handler_begin = NULL;
 688       }
 689       if (offsets->value(CodeOffsets::DeoptMH) != -1) {
 690         _deopt_mh_handler_begin  = (address) this + code_offset()          + offsets->value(CodeOffsets::DeoptMH);
 691       } else {
 692         _deopt_mh_handler_begin = NULL;
 693       }
 694     } else {
 695 #endif
 696     // Exception handler and deopt handler are in the stub section
 697     assert(offsets->value(CodeOffsets::Exceptions) != -1, "must be set");
 698     assert(offsets->value(CodeOffsets::Deopt     ) != -1, "must be set");
 699 
 700     _exception_offset       = _stub_offset          + offsets->value(CodeOffsets::Exceptions);
 701     _deopt_handler_begin    = (address) this + _stub_offset          + offsets->value(CodeOffsets::Deopt);
 702     if (offsets->value(CodeOffsets::DeoptMH) != -1) {
 703       _deopt_mh_handler_begin  = (address) this + _stub_offset          + offsets->value(CodeOffsets::DeoptMH);
 704     } else {
 705       _deopt_mh_handler_begin  = NULL;
 706 #if INCLUDE_JVMCI
 707     }
 708 #endif
 709     }
 710     if (offsets->value(CodeOffsets::UnwindHandler) != -1) {
 711       _unwind_handler_offset = code_offset()         + offsets->value(CodeOffsets::UnwindHandler);
 712     } else {
 713       _unwind_handler_offset = -1;
 714     }
 715 
 716     _oops_offset             = data_offset();
 717     _metadata_offset         = _oops_offset          + align_up(code_buffer->total_oop_size(), oopSize);
 718     int scopes_data_offset   = _metadata_offset      + align_up(code_buffer->total_metadata_size(), wordSize);
 719 
 720     _scopes_pcs_offset       = scopes_data_offset    + align_up(debug_info->data_size       (), oopSize);
 721     _dependencies_offset     = _scopes_pcs_offset    + adjust_pcs_size(debug_info->pcs_size());
 722     _handler_table_offset    = _dependencies_offset  + align_up((int)dependencies->size_in_bytes (), oopSize);
 723     _nul_chk_table_offset    = _handler_table_offset + align_up(handler_table->size_in_bytes(), oopSize);
 724     _nmethod_end_offset      = _nul_chk_table_offset + align_up(nul_chk_table->size_in_bytes(), oopSize);
 725     _entry_point             = code_begin()          + offsets->value(CodeOffsets::Entry);
 726     _verified_entry_point    = code_begin()          + offsets->value(CodeOffsets::Verified_Entry);
 727     _osr_entry_point         = code_begin()          + offsets->value(CodeOffsets::OSR_Entry);
 728     _exception_cache         = NULL;
 729 
 730     _scopes_data_begin = (address) this + scopes_data_offset;
 731 
 732     _pc_desc_container.reset_to(scopes_pcs_begin());
 733 
 734     code_buffer->copy_code_and_locs_to(this);
 735     // Copy contents of ScopeDescRecorder to nmethod
 736     code_buffer->copy_values_to(this);
 737     debug_info->copy_to(this);
 738     dependencies->copy_to(this);
 739     if (ScavengeRootsInCode) {
 740       Universe::heap()->register_nmethod(this);
 741     }
 742     debug_only(Universe::heap()->verify_nmethod(this));
 743 
 744     CodeCache::commit(this);
 745 
 746     // Copy contents of ExceptionHandlerTable to nmethod
 747     handler_table->copy_to(this);
 748     nul_chk_table->copy_to(this);
 749 
 750     // we use the information of entry points to find out if a method is
 751     // static or non static
 752     assert(compiler->is_c2() || compiler->is_jvmci() ||
 753            _method->is_static() == (entry_point() == _verified_entry_point),
 754            " entry points must be same for static methods and vice versa");
 755   }
 756 }
 757 
 758 // Print a short set of xml attributes to identify this nmethod.  The
 759 // output should be embedded in some other element.
 760 void nmethod::log_identity(xmlStream* log) const {
 761   log->print(" compile_id='%d'", compile_id());
 762   const char* nm_kind = compile_kind();
 763   if (nm_kind != NULL)  log->print(" compile_kind='%s'", nm_kind);
 764   log->print(" compiler='%s'", compiler_name());
 765   if (TieredCompilation) {
 766     log->print(" level='%d'", comp_level());
 767   }
 768 }
 769 
 770 
 771 #define LOG_OFFSET(log, name)                    \
 772   if (p2i(name##_end()) - p2i(name##_begin())) \
 773     log->print(" " XSTR(name) "_offset='" INTX_FORMAT "'"    , \
 774                p2i(name##_begin()) - p2i(this))
 775 
 776 
 777 void nmethod::log_new_nmethod() const {
 778   if (LogCompilation && xtty != NULL) {
 779     ttyLocker ttyl;
 780     HandleMark hm;
 781     xtty->begin_elem("nmethod");
 782     log_identity(xtty);
 783     xtty->print(" entry='" INTPTR_FORMAT "' size='%d'", p2i(code_begin()), size());
 784     xtty->print(" address='" INTPTR_FORMAT "'", p2i(this));
 785 
 786     LOG_OFFSET(xtty, relocation);
 787     LOG_OFFSET(xtty, consts);
 788     LOG_OFFSET(xtty, insts);
 789     LOG_OFFSET(xtty, stub);
 790     LOG_OFFSET(xtty, scopes_data);
 791     LOG_OFFSET(xtty, scopes_pcs);
 792     LOG_OFFSET(xtty, dependencies);
 793     LOG_OFFSET(xtty, handler_table);
 794     LOG_OFFSET(xtty, nul_chk_table);
 795     LOG_OFFSET(xtty, oops);
 796     LOG_OFFSET(xtty, metadata);
 797 
 798     xtty->method(method());
 799     xtty->stamp();
 800     xtty->end_elem();
 801   }
 802 }
 803 
 804 #undef LOG_OFFSET
 805 
 806 
 807 // Print out more verbose output usually for a newly created nmethod.
 808 void nmethod::print_on(outputStream* st, const char* msg) const {
 809   if (st != NULL) {
 810     ttyLocker ttyl;
 811     if (WizardMode) {
 812       CompileTask::print(st, this, msg, /*short_form:*/ true);
 813       st->print_cr(" (" INTPTR_FORMAT ")", p2i(this));
 814     } else {
 815       CompileTask::print(st, this, msg, /*short_form:*/ false);
 816     }
 817   }
 818 }
 819 
 820 void nmethod::maybe_print_nmethod(DirectiveSet* directive) {
 821   bool printnmethods = directive->PrintAssemblyOption || directive->PrintNMethodsOption;
 822   if (printnmethods || PrintDebugInfo || PrintRelocations || PrintDependencies || PrintExceptionHandlers) {
 823     print_nmethod(printnmethods);
 824   }
 825 }
 826 
 827 void nmethod::print_nmethod(bool printmethod) {
 828   ttyLocker ttyl;  // keep the following output all in one block
 829   if (xtty != NULL) {
 830     xtty->begin_head("print_nmethod");
 831     xtty->stamp();
 832     xtty->end_head();
 833   }
 834   // print the header part first
 835   print();
 836   // then print the requested information
 837   if (printmethod) {
 838     print_code();
 839     print_pcs();
 840     if (oop_maps()) {
 841       oop_maps()->print();
 842     }
 843   }
 844   if (printmethod || PrintDebugInfo || CompilerOracle::has_option_string(_method, "PrintDebugInfo")) {
 845     print_scopes();
 846   }
 847   if (printmethod || PrintRelocations || CompilerOracle::has_option_string(_method, "PrintRelocations")) {
 848     print_relocations();
 849   }
 850   if (printmethod || PrintDependencies || CompilerOracle::has_option_string(_method, "PrintDependencies")) {
 851     print_dependencies();
 852   }
 853   if (printmethod || PrintExceptionHandlers) {
 854     print_handler_table();
 855     print_nul_chk_table();
 856   }
 857   if (printmethod) {
 858     print_recorded_oops();
 859     print_recorded_metadata();
 860   }
 861   if (xtty != NULL) {
 862     xtty->tail("print_nmethod");
 863   }
 864 }
 865 
 866 
 867 // Promote one word from an assembly-time handle to a live embedded oop.
 868 inline void nmethod::initialize_immediate_oop(oop* dest, jobject handle) {
 869   if (handle == NULL ||
 870       // As a special case, IC oops are initialized to 1 or -1.
 871       handle == (jobject) Universe::non_oop_word()) {
 872     (*dest) = (oop) handle;
 873   } else {
 874     (*dest) = JNIHandles::resolve_non_null(handle);
 875   }
 876 }
 877 
 878 
 879 // Have to have the same name because it's called by a template
 880 void nmethod::copy_values(GrowableArray<jobject>* array) {
 881   int length = array->length();
 882   assert((address)(oops_begin() + length) <= (address)oops_end(), "oops big enough");
 883   oop* dest = oops_begin();
 884   for (int index = 0 ; index < length; index++) {
 885     initialize_immediate_oop(&dest[index], array->at(index));
 886   }
 887 
 888   // Now we can fix up all the oops in the code.  We need to do this
 889   // in the code because the assembler uses jobjects as placeholders.
 890   // The code and relocations have already been initialized by the
 891   // CodeBlob constructor, so it is valid even at this early point to
 892   // iterate over relocations and patch the code.
 893   fix_oop_relocations(NULL, NULL, /*initialize_immediates=*/ true);
 894 }
 895 
 896 void nmethod::copy_values(GrowableArray<Metadata*>* array) {
 897   int length = array->length();
 898   assert((address)(metadata_begin() + length) <= (address)metadata_end(), "big enough");
 899   Metadata** dest = metadata_begin();
 900   for (int index = 0 ; index < length; index++) {
 901     dest[index] = array->at(index);
 902   }
 903 }
 904 
 905 void nmethod::fix_oop_relocations(address begin, address end, bool initialize_immediates) {
 906   // re-patch all oop-bearing instructions, just in case some oops moved
 907   RelocIterator iter(this, begin, end);
 908   while (iter.next()) {
 909     if (iter.type() == relocInfo::oop_type) {
 910       oop_Relocation* reloc = iter.oop_reloc();
 911       if (initialize_immediates && reloc->oop_is_immediate()) {
 912         oop* dest = reloc->oop_addr();
 913         initialize_immediate_oop(dest, (jobject) *dest);
 914       }
 915       // Refresh the oop-related bits of this instruction.
 916       reloc->fix_oop_relocation();
 917     } else if (iter.type() == relocInfo::metadata_type) {
 918       metadata_Relocation* reloc = iter.metadata_reloc();
 919       reloc->fix_metadata_relocation();
 920     }
 921   }
 922 }
 923 
 924 
 925 void nmethod::verify_clean_inline_caches() {
 926   assert_locked_or_safepoint(CompiledIC_lock);
 927 
 928   // If the method is not entrant or zombie then a JMP is plastered over the
 929   // first few bytes.  If an oop in the old code was there, that oop
 930   // should not get GC'd.  Skip the first few bytes of oops on
 931   // not-entrant methods.
 932   address low_boundary = verified_entry_point();
 933   if (!is_in_use()) {
 934     low_boundary += NativeJump::instruction_size;
 935     // %%% Note:  On SPARC we patch only a 4-byte trap, not a full NativeJump.
 936     // This means that the low_boundary is going to be a little too high.
 937     // This shouldn't matter, since oops of non-entrant methods are never used.
 938     // In fact, why are we bothering to look at oops in a non-entrant method??
 939   }
 940 
 941   ResourceMark rm;
 942   RelocIterator iter(this, low_boundary);
 943   while(iter.next()) {
 944     switch(iter.type()) {
 945       case relocInfo::virtual_call_type:
 946       case relocInfo::opt_virtual_call_type: {
 947         CompiledIC *ic = CompiledIC_at(&iter);
 948         // Ok, to lookup references to zombies here
 949         CodeBlob *cb = CodeCache::find_blob_unsafe(ic->ic_destination());
 950         nmethod* nm = cb->as_nmethod_or_null();
 951         if( nm != NULL ) {
 952           // Verify that inline caches pointing to both zombie and not_entrant methods are clean
 953           if (!nm->is_in_use() || (nm->method()->code() != nm)) {
 954             assert(ic->is_clean(), "IC should be clean");
 955           }
 956         }
 957         break;
 958       }
 959       case relocInfo::static_call_type: {
 960         CompiledStaticCall *csc = compiledStaticCall_at(iter.reloc());
 961         CodeBlob *cb = CodeCache::find_blob_unsafe(csc->destination());
 962         nmethod* nm = cb->as_nmethod_or_null();
 963         if( nm != NULL ) {
 964           // Verify that inline caches pointing to both zombie and not_entrant methods are clean
 965           if (!nm->is_in_use() || (nm->method()->code() != nm)) {
 966             assert(csc->is_clean(), "IC should be clean");
 967           }
 968         }
 969         break;
 970       }
 971       default:
 972         break;
 973     }
 974   }
 975 }
 976 
 977 // This is a private interface with the sweeper.
 978 void nmethod::mark_as_seen_on_stack() {
 979   assert(is_alive(), "Must be an alive method");
 980   // Set the traversal mark to ensure that the sweeper does 2
 981   // cleaning passes before moving to zombie.
 982   set_stack_traversal_mark(NMethodSweeper::traversal_count());
 983 }
 984 
 985 // Tell if a non-entrant method can be converted to a zombie (i.e.,
 986 // there are no activations on the stack, not in use by the VM,
 987 // and not in use by the ServiceThread)
 988 bool nmethod::can_convert_to_zombie() {
 989   assert(is_not_entrant(), "must be a non-entrant method");
 990 
 991   // Since the nmethod sweeper only does partial sweep the sweeper's traversal
 992   // count can be greater than the stack traversal count before it hits the
 993   // nmethod for the second time.
 994   return stack_traversal_mark()+1 < NMethodSweeper::traversal_count() &&
 995          !is_locked_by_vm();
 996 }
 997 
 998 void nmethod::inc_decompile_count() {
 999   if (!is_compiled_by_c2() && !is_compiled_by_jvmci()) return;
1000   // Could be gated by ProfileTraps, but do not bother...
1001   Method* m = method();
1002   if (m == NULL)  return;
1003   MethodData* mdo = m->method_data();
1004   if (mdo == NULL)  return;
1005   // There is a benign race here.  See comments in methodData.hpp.
1006   mdo->inc_decompile_count();
1007 }
1008 
1009 void nmethod::make_unloaded(BoolObjectClosure* is_alive, oop cause) {
1010 
1011   post_compiled_method_unload();
1012 
1013   // Since this nmethod is being unloaded, make sure that dependencies
1014   // recorded in instanceKlasses get flushed and pass non-NULL closure to
1015   // indicate that this work is being done during a GC.
1016   assert(Universe::heap()->is_gc_active(), "should only be called during gc");
1017   assert(is_alive != NULL, "Should be non-NULL");
1018   // A non-NULL is_alive closure indicates that this is being called during GC.
1019   flush_dependencies(is_alive);
1020 
1021   // Break cycle between nmethod & method
1022   LogTarget(Trace, class, unload) lt;
1023   if (lt.is_enabled()) {
1024     LogStream ls(lt);
1025     ls.print_cr("making nmethod " INTPTR_FORMAT
1026                   " unloadable, Method*(" INTPTR_FORMAT
1027                   "), cause(" INTPTR_FORMAT ")",
1028                   p2i(this), p2i(_method), p2i(cause));
1029     if (!Universe::heap()->is_gc_active())
1030       cause->klass()->print_on(&ls);
1031   }
1032   // Unlink the osr method, so we do not look this up again
1033   if (is_osr_method()) {
1034     // Invalidate the osr nmethod only once
1035     if (is_in_use()) {
1036       invalidate_osr_method();
1037     }
1038 #ifdef ASSERT
1039     if (method() != NULL) {
1040       // Make sure osr nmethod is invalidated, i.e. not on the list
1041       bool found = method()->method_holder()->remove_osr_nmethod(this);
1042       assert(!found, "osr nmethod should have been invalidated");
1043     }
1044 #endif
1045   }
1046 
1047   // If _method is already NULL the Method* is about to be unloaded,
1048   // so we don't have to break the cycle. Note that it is possible to
1049   // have the Method* live here, in case we unload the nmethod because
1050   // it is pointing to some oop (other than the Method*) being unloaded.
1051   if (_method != NULL) {
1052     // OSR methods point to the Method*, but the Method* does not
1053     // point back!
1054     if (_method->code() == this) {
1055       _method->clear_code(); // Break a cycle
1056     }
1057     _method = NULL;            // Clear the method of this dead nmethod
1058   }
1059 
1060   // Make the class unloaded - i.e., change state and notify sweeper
1061   assert(SafepointSynchronize::is_at_safepoint(), "must be at safepoint");
1062   if (is_in_use()) {
1063     // Transitioning directly from live to unloaded -- so
1064     // we need to force a cache clean-up; remember this
1065     // for later on.
1066     CodeCache::set_needs_cache_clean(true);
1067   }
1068 
1069   // Unregister must be done before the state change
1070   Universe::heap()->unregister_nmethod(this);
1071 
1072   _state = unloaded;
1073 
1074   // Log the unloading.
1075   log_state_change();
1076 
1077 #if INCLUDE_JVMCI
1078   // The method can only be unloaded after the pointer to the installed code
1079   // Java wrapper is no longer alive. Here we need to clear out this weak
1080   // reference to the dead object. Nulling out the reference has to happen
1081   // after the method is unregistered since the original value may be still
1082   // tracked by the rset.
1083   maybe_invalidate_installed_code();
1084   // Clear these out after the nmethod has been unregistered and any
1085   // updates to the InstalledCode instance have been performed.
1086   _jvmci_installed_code = NULL;
1087   _speculation_log = NULL;
1088 #endif
1089 
1090   // The Method* is gone at this point
1091   assert(_method == NULL, "Tautology");
1092 
1093   set_osr_link(NULL);
1094   NMethodSweeper::report_state_change(this);
1095 }
1096 
1097 void nmethod::invalidate_osr_method() {
1098   assert(_entry_bci != InvocationEntryBci, "wrong kind of nmethod");
1099   // Remove from list of active nmethods
1100   if (method() != NULL) {
1101     method()->method_holder()->remove_osr_nmethod(this);
1102   }
1103 }
1104 
1105 void nmethod::log_state_change() const {
1106   if (LogCompilation) {
1107     if (xtty != NULL) {
1108       ttyLocker ttyl;  // keep the following output all in one block
1109       if (_state == unloaded) {
1110         xtty->begin_elem("make_unloaded thread='" UINTX_FORMAT "'",
1111                          os::current_thread_id());
1112       } else {
1113         xtty->begin_elem("make_not_entrant thread='" UINTX_FORMAT "'%s",
1114                          os::current_thread_id(),
1115                          (_state == zombie ? " zombie='1'" : ""));
1116       }
1117       log_identity(xtty);
1118       xtty->stamp();
1119       xtty->end_elem();
1120     }
1121   }
1122 
1123   const char *state_msg = _state == zombie ? "made zombie" : "made not entrant";
1124   CompileTask::print_ul(this, state_msg);
1125   if (PrintCompilation && _state != unloaded) {
1126     print_on(tty, state_msg);
1127   }
1128 }
1129 
1130 /**
1131  * Common functionality for both make_not_entrant and make_zombie
1132  */
1133 bool nmethod::make_not_entrant_or_zombie(unsigned int state) {
1134   assert(state == zombie || state == not_entrant, "must be zombie or not_entrant");
1135   assert(!is_zombie(), "should not already be a zombie");
1136 
1137   if (_state == state) {
1138     // Avoid taking the lock if already in required state.
1139     // This is safe from races because the state is an end-state,
1140     // which the nmethod cannot back out of once entered.
1141     // No need for fencing either.
1142     return false;
1143   }
1144 
1145   // Make sure neither the nmethod nor the method is flushed in case of a safepoint in code below.
1146   nmethodLocker nml(this);
1147   methodHandle the_method(method());
1148   NoSafepointVerifier nsv;
1149 
1150   // during patching, depending on the nmethod state we must notify the GC that
1151   // code has been unloaded, unregistering it. We cannot do this right while
1152   // holding the Patching_lock because we need to use the CodeCache_lock. This
1153   // would be prone to deadlocks.
1154   // This flag is used to remember whether we need to later lock and unregister.
1155   bool nmethod_needs_unregister = false;
1156 
1157   {
1158     // invalidate osr nmethod before acquiring the patching lock since
1159     // they both acquire leaf locks and we don't want a deadlock.
1160     // This logic is equivalent to the logic below for patching the
1161     // verified entry point of regular methods. We check that the
1162     // nmethod is in use to ensure that it is invalidated only once.
1163     if (is_osr_method() && is_in_use()) {
1164       // this effectively makes the osr nmethod not entrant
1165       invalidate_osr_method();
1166     }
1167 
1168     // Enter critical section.  Does not block for safepoint.
1169     MutexLockerEx pl(Patching_lock, Mutex::_no_safepoint_check_flag);
1170 
1171     if (_state == state) {
1172       // another thread already performed this transition so nothing
1173       // to do, but return false to indicate this.
1174       return false;
1175     }
1176 
1177     // The caller can be calling the method statically or through an inline
1178     // cache call.
1179     if (!is_osr_method() && !is_not_entrant()) {
1180       NativeJump::patch_verified_entry(entry_point(), verified_entry_point(),
1181                   SharedRuntime::get_handle_wrong_method_stub());
1182     }
1183 
1184     if (is_in_use() && update_recompile_counts()) {
1185       // It's a true state change, so mark the method as decompiled.
1186       // Do it only for transition from alive.
1187       inc_decompile_count();
1188     }
1189 
1190     // If the state is becoming a zombie, signal to unregister the nmethod with
1191     // the heap.
1192     // This nmethod may have already been unloaded during a full GC.
1193     if ((state == zombie) && !is_unloaded()) {
1194       nmethod_needs_unregister = true;
1195     }
1196 
1197     // Must happen before state change. Otherwise we have a race condition in
1198     // nmethod::can_not_entrant_be_converted(). I.e., a method can immediately
1199     // transition its state from 'not_entrant' to 'zombie' without having to wait
1200     // for stack scanning.
1201     if (state == not_entrant) {
1202       mark_as_seen_on_stack();
1203       OrderAccess::storestore(); // _stack_traversal_mark and _state
1204     }
1205 
1206     // Change state
1207     _state = state;
1208 
1209     // Log the transition once
1210     log_state_change();
1211 
1212     // Invalidate while holding the patching lock
1213     JVMCI_ONLY(maybe_invalidate_installed_code());
1214 
1215     // Remove nmethod from method.
1216     // We need to check if both the _code and _from_compiled_code_entry_point
1217     // refer to this nmethod because there is a race in setting these two fields
1218     // in Method* as seen in bugid 4947125.
1219     // If the vep() points to the zombie nmethod, the memory for the nmethod
1220     // could be flushed and the compiler and vtable stubs could still call
1221     // through it.
1222     if (method() != NULL && (method()->code() == this ||
1223                              method()->from_compiled_entry() == verified_entry_point())) {
1224       HandleMark hm;
1225       method()->clear_code(false /* already owns Patching_lock */);
1226     }
1227   } // leave critical region under Patching_lock
1228 
1229 #ifdef ASSERT
1230   if (is_osr_method() && method() != NULL) {
1231     // Make sure osr nmethod is invalidated, i.e. not on the list
1232     bool found = method()->method_holder()->remove_osr_nmethod(this);
1233     assert(!found, "osr nmethod should have been invalidated");
1234   }
1235 #endif
1236 
1237   // When the nmethod becomes zombie it is no longer alive so the
1238   // dependencies must be flushed.  nmethods in the not_entrant
1239   // state will be flushed later when the transition to zombie
1240   // happens or they get unloaded.
1241   if (state == zombie) {
1242     {
1243       // Flushing dependencies must be done before any possible
1244       // safepoint can sneak in, otherwise the oops used by the
1245       // dependency logic could have become stale.
1246       MutexLockerEx mu(CodeCache_lock, Mutex::_no_safepoint_check_flag);
1247       if (nmethod_needs_unregister) {
1248         Universe::heap()->unregister_nmethod(this);
1249 #ifdef JVMCI
1250         _jvmci_installed_code = NULL;
1251         _speculation_log = NULL;
1252 #endif
1253       }
1254       flush_dependencies(NULL);
1255     }
1256 
1257     // zombie only - if a JVMTI agent has enabled the CompiledMethodUnload
1258     // event and it hasn't already been reported for this nmethod then
1259     // report it now. The event may have been reported earlier if the GC
1260     // marked it for unloading). JvmtiDeferredEventQueue support means
1261     // we no longer go to a safepoint here.
1262     post_compiled_method_unload();
1263 
1264 #ifdef ASSERT
1265     // It's no longer safe to access the oops section since zombie
1266     // nmethods aren't scanned for GC.
1267     _oops_are_stale = true;
1268 #endif
1269      // the Method may be reclaimed by class unloading now that the
1270      // nmethod is in zombie state
1271     set_method(NULL);
1272   } else {
1273     assert(state == not_entrant, "other cases may need to be handled differently");
1274   }
1275 
1276   if (TraceCreateZombies) {
1277     ResourceMark m;
1278     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");
1279   }
1280 
1281   NMethodSweeper::report_state_change(this);
1282   return true;
1283 }
1284 
1285 void nmethod::flush() {
1286   // Note that there are no valid oops in the nmethod anymore.
1287   assert(!is_osr_method() || is_unloaded() || is_zombie(),
1288          "osr nmethod must be unloaded or zombie before flushing");
1289   assert(is_zombie() || is_osr_method(), "must be a zombie method");
1290   assert (!is_locked_by_vm(), "locked methods shouldn't be flushed");
1291   assert_locked_or_safepoint(CodeCache_lock);
1292 
1293   // completely deallocate this method
1294   Events::log(JavaThread::current(), "flushing nmethod " INTPTR_FORMAT, p2i(this));
1295   if (PrintMethodFlushing) {
1296     tty->print_cr("*flushing %s nmethod %3d/" INTPTR_FORMAT ". Live blobs:" UINT32_FORMAT
1297                   "/Free CodeCache:" SIZE_FORMAT "Kb",
1298                   is_osr_method() ? "osr" : "",_compile_id, p2i(this), CodeCache::blob_count(),
1299                   CodeCache::unallocated_capacity(CodeCache::get_code_blob_type(this))/1024);
1300   }
1301 
1302   // We need to deallocate any ExceptionCache data.
1303   // Note that we do not need to grab the nmethod lock for this, it
1304   // better be thread safe if we're disposing of it!
1305   ExceptionCache* ec = exception_cache();
1306   set_exception_cache(NULL);
1307   while(ec != NULL) {
1308     ExceptionCache* next = ec->next();
1309     delete ec;
1310     ec = next;
1311   }
1312 
1313   if (on_scavenge_root_list()) {
1314     CodeCache::drop_scavenge_root_nmethod(this);
1315   }
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   bool is_unloaded = false;
1504   // Follow JVMCI method
1505   BarrierSet* bs = Universe::heap()->barrier_set();
1506   if (_jvmci_installed_code != NULL) {
1507     if (_jvmci_installed_code->is_a(HotSpotNmethod::klass()) && HotSpotNmethod::isDefault(_jvmci_installed_code)) {
1508       if (!is_alive->do_object_b(_jvmci_installed_code)) {
1509         clear_jvmci_installed_code();
1510       }
1511     } else {
1512       if (can_unload(is_alive, (oop*)&_jvmci_installed_code, unloading_occurred)) {
1513         return true;
1514       }
1515     }
1516   }
1517 
1518   if (_speculation_log != NULL) {
1519     if (!is_alive->do_object_b(_speculation_log)) {
1520       bs->write_ref_nmethod_pre(&_speculation_log, this);
1521       _speculation_log = NULL;
1522       bs->write_ref_nmethod_post(&_speculation_log, this);
1523     }
1524   }
1525   return is_unloaded;
1526 }
1527 #endif
1528 
1529 // Iterate over metadata calling this function.   Used by RedefineClasses
1530 void nmethod::metadata_do(void f(Metadata*)) {
1531   address low_boundary = verified_entry_point();
1532   if (is_not_entrant()) {
1533     low_boundary += NativeJump::instruction_size;
1534     // %%% Note:  On SPARC we patch only a 4-byte trap, not a full NativeJump.
1535     // (See comment above.)
1536   }
1537   {
1538     // Visit all immediate references that are embedded in the instruction stream.
1539     RelocIterator iter(this, low_boundary);
1540     while (iter.next()) {
1541       if (iter.type() == relocInfo::metadata_type ) {
1542         metadata_Relocation* r = iter.metadata_reloc();
1543         // In this metadata, we must only follow those metadatas directly embedded in
1544         // the code.  Other metadatas (oop_index>0) are seen as part of
1545         // the metadata section below.
1546         assert(1 == (r->metadata_is_immediate()) +
1547                (r->metadata_addr() >= metadata_begin() && r->metadata_addr() < metadata_end()),
1548                "metadata must be found in exactly one place");
1549         if (r->metadata_is_immediate() && r->metadata_value() != NULL) {
1550           Metadata* md = r->metadata_value();
1551           if (md != _method) f(md);
1552         }
1553       } else if (iter.type() == relocInfo::virtual_call_type) {
1554         // Check compiledIC holders associated with this nmethod
1555         CompiledIC *ic = CompiledIC_at(&iter);
1556         if (ic->is_icholder_call()) {
1557           CompiledICHolder* cichk = ic->cached_icholder();
1558           f(cichk->holder_method());
1559           f(cichk->holder_klass());
1560         } else {
1561           Metadata* ic_oop = ic->cached_metadata();
1562           if (ic_oop != NULL) {
1563             f(ic_oop);
1564           }
1565         }
1566       }
1567     }
1568   }
1569 
1570   // Visit the metadata section
1571   for (Metadata** p = metadata_begin(); p < metadata_end(); p++) {
1572     if (*p == Universe::non_oop_word() || *p == NULL)  continue;  // skip non-oops
1573     Metadata* md = *p;
1574     f(md);
1575   }
1576 
1577   // Visit metadata not embedded in the other places.
1578   if (_method != NULL) f(_method);
1579 }
1580 
1581 void nmethod::oops_do(OopClosure* f, bool allow_zombie) {
1582   // make sure the oops ready to receive visitors
1583   assert(allow_zombie || !is_zombie(), "should not call follow on zombie nmethod");
1584   assert(!is_unloaded(), "should not call follow on unloaded nmethod");
1585 
1586   // If the method is not entrant or zombie then a JMP is plastered over the
1587   // first few bytes.  If an oop in the old code was there, that oop
1588   // should not get GC'd.  Skip the first few bytes of oops on
1589   // not-entrant methods.
1590   address low_boundary = verified_entry_point();
1591   if (is_not_entrant()) {
1592     low_boundary += NativeJump::instruction_size;
1593     // %%% Note:  On SPARC we patch only a 4-byte trap, not a full NativeJump.
1594     // (See comment above.)
1595   }
1596 
1597 #if INCLUDE_JVMCI
1598   if (_jvmci_installed_code != NULL) {
1599     f->do_oop((oop*) &_jvmci_installed_code);
1600   }
1601   if (_speculation_log != NULL) {
1602     f->do_oop((oop*) &_speculation_log);
1603   }
1604 #endif
1605 
1606   RelocIterator iter(this, low_boundary);
1607 
1608   while (iter.next()) {
1609     if (iter.type() == relocInfo::oop_type ) {
1610       oop_Relocation* r = iter.oop_reloc();
1611       // In this loop, we must only follow those oops directly embedded in
1612       // the code.  Other oops (oop_index>0) are seen as part of scopes_oops.
1613       assert(1 == (r->oop_is_immediate()) +
1614                    (r->oop_addr() >= oops_begin() && r->oop_addr() < oops_end()),
1615              "oop must be found in exactly one place");
1616       if (r->oop_is_immediate() && r->oop_value() != NULL) {
1617         f->do_oop(r->oop_addr());
1618       }
1619     }
1620   }
1621 
1622   // Scopes
1623   // This includes oop constants not inlined in the code stream.
1624   for (oop* p = oops_begin(); p < oops_end(); p++) {
1625     if (*p == Universe::non_oop_word())  continue;  // skip non-oops
1626     f->do_oop(p);
1627   }
1628 }
1629 
1630 #define NMETHOD_SENTINEL ((nmethod*)badAddress)
1631 
1632 nmethod* volatile nmethod::_oops_do_mark_nmethods;
1633 
1634 // An nmethod is "marked" if its _mark_link is set non-null.
1635 // Even if it is the end of the linked list, it will have a non-null link value,
1636 // as long as it is on the list.
1637 // This code must be MP safe, because it is used from parallel GC passes.
1638 bool nmethod::test_set_oops_do_mark() {
1639   assert(nmethod::oops_do_marking_is_active(), "oops_do_marking_prologue must be called");
1640   nmethod* observed_mark_link = _oops_do_mark_link;
1641   if (observed_mark_link == NULL) {
1642     // Claim this nmethod for this thread to mark.
1643     observed_mark_link = (nmethod*)
1644       Atomic::cmpxchg_ptr(NMETHOD_SENTINEL, &_oops_do_mark_link, NULL);
1645     if (observed_mark_link == NULL) {
1646 
1647       // Atomically append this nmethod (now claimed) to the head of the list:
1648       nmethod* observed_mark_nmethods = _oops_do_mark_nmethods;
1649       for (;;) {
1650         nmethod* required_mark_nmethods = observed_mark_nmethods;
1651         _oops_do_mark_link = required_mark_nmethods;
1652         observed_mark_nmethods = (nmethod*)
1653           Atomic::cmpxchg_ptr(this, &_oops_do_mark_nmethods, required_mark_nmethods);
1654         if (observed_mark_nmethods == required_mark_nmethods)
1655           break;
1656       }
1657       // Mark was clear when we first saw this guy.
1658       if (TraceScavenge) { print_on(tty, "oops_do, mark"); }
1659       return false;
1660     }
1661   }
1662   // On fall through, another racing thread marked this nmethod before we did.
1663   return true;
1664 }
1665 
1666 void nmethod::oops_do_marking_prologue() {
1667   if (TraceScavenge) { tty->print_cr("[oops_do_marking_prologue"); }
1668   assert(_oops_do_mark_nmethods == NULL, "must not call oops_do_marking_prologue twice in a row");
1669   // We use cmpxchg_ptr instead of regular assignment here because the user
1670   // may fork a bunch of threads, and we need them all to see the same state.
1671   void* observed = Atomic::cmpxchg_ptr(NMETHOD_SENTINEL, &_oops_do_mark_nmethods, NULL);
1672   guarantee(observed == NULL, "no races in this sequential code");
1673 }
1674 
1675 void nmethod::oops_do_marking_epilogue() {
1676   assert(_oops_do_mark_nmethods != NULL, "must not call oops_do_marking_epilogue twice in a row");
1677   nmethod* cur = _oops_do_mark_nmethods;
1678   while (cur != NMETHOD_SENTINEL) {
1679     assert(cur != NULL, "not NULL-terminated");
1680     nmethod* next = cur->_oops_do_mark_link;
1681     cur->_oops_do_mark_link = NULL;
1682     DEBUG_ONLY(cur->verify_oop_relocations());
1683     NOT_PRODUCT(if (TraceScavenge)  cur->print_on(tty, "oops_do, unmark"));
1684     cur = next;
1685   }
1686   void* required = _oops_do_mark_nmethods;
1687   void* observed = Atomic::cmpxchg_ptr(NULL, &_oops_do_mark_nmethods, required);
1688   guarantee(observed == required, "no races in this sequential code");
1689   if (TraceScavenge) { tty->print_cr("oops_do_marking_epilogue]"); }
1690 }
1691 
1692 class DetectScavengeRoot: public OopClosure {
1693   bool     _detected_scavenge_root;
1694 public:
1695   DetectScavengeRoot() : _detected_scavenge_root(false)
1696   { NOT_PRODUCT(_print_nm = NULL); }
1697   bool detected_scavenge_root() { return _detected_scavenge_root; }
1698   virtual void do_oop(oop* p) {
1699     if ((*p) != NULL && (*p)->is_scavengable()) {
1700       NOT_PRODUCT(maybe_print(p));
1701       _detected_scavenge_root = true;
1702     }
1703   }
1704   virtual void do_oop(narrowOop* p) { ShouldNotReachHere(); }
1705 
1706 #ifndef PRODUCT
1707   nmethod* _print_nm;
1708   void maybe_print(oop* p) {
1709     if (_print_nm == NULL)  return;
1710     if (!_detected_scavenge_root)  _print_nm->print_on(tty, "new scavenge root");
1711     tty->print_cr("" PTR_FORMAT "[offset=%d] detected scavengable oop " PTR_FORMAT " (found at " PTR_FORMAT ")",
1712                   p2i(_print_nm), (int)((intptr_t)p - (intptr_t)_print_nm),
1713                   p2i(*p), p2i(p));
1714     (*p)->print();
1715   }
1716 #endif //PRODUCT
1717 };
1718 
1719 bool nmethod::detect_scavenge_root_oops() {
1720   DetectScavengeRoot detect_scavenge_root;
1721   NOT_PRODUCT(if (TraceScavenge)  detect_scavenge_root._print_nm = this);
1722   oops_do(&detect_scavenge_root);
1723   return detect_scavenge_root.detected_scavenge_root();
1724 }
1725 
1726 inline bool includes(void* p, void* from, void* to) {
1727   return from <= p && p < to;
1728 }
1729 
1730 
1731 void nmethod::copy_scopes_pcs(PcDesc* pcs, int count) {
1732   assert(count >= 2, "must be sentinel values, at least");
1733 
1734 #ifdef ASSERT
1735   // must be sorted and unique; we do a binary search in find_pc_desc()
1736   int prev_offset = pcs[0].pc_offset();
1737   assert(prev_offset == PcDesc::lower_offset_limit,
1738          "must start with a sentinel");
1739   for (int i = 1; i < count; i++) {
1740     int this_offset = pcs[i].pc_offset();
1741     assert(this_offset > prev_offset, "offsets must be sorted");
1742     prev_offset = this_offset;
1743   }
1744   assert(prev_offset == PcDesc::upper_offset_limit,
1745          "must end with a sentinel");
1746 #endif //ASSERT
1747 
1748   // Search for MethodHandle invokes and tag the nmethod.
1749   for (int i = 0; i < count; i++) {
1750     if (pcs[i].is_method_handle_invoke()) {
1751       set_has_method_handle_invokes(true);
1752       break;
1753     }
1754   }
1755   assert(has_method_handle_invokes() == (_deopt_mh_handler_begin != NULL), "must have deopt mh handler");
1756 
1757   int size = count * sizeof(PcDesc);
1758   assert(scopes_pcs_size() >= size, "oob");
1759   memcpy(scopes_pcs_begin(), pcs, size);
1760 
1761   // Adjust the final sentinel downward.
1762   PcDesc* last_pc = &scopes_pcs_begin()[count-1];
1763   assert(last_pc->pc_offset() == PcDesc::upper_offset_limit, "sanity");
1764   last_pc->set_pc_offset(content_size() + 1);
1765   for (; last_pc + 1 < scopes_pcs_end(); last_pc += 1) {
1766     // Fill any rounding gaps with copies of the last record.
1767     last_pc[1] = last_pc[0];
1768   }
1769   // The following assert could fail if sizeof(PcDesc) is not
1770   // an integral multiple of oopSize (the rounding term).
1771   // If it fails, change the logic to always allocate a multiple
1772   // of sizeof(PcDesc), and fill unused words with copies of *last_pc.
1773   assert(last_pc + 1 == scopes_pcs_end(), "must match exactly");
1774 }
1775 
1776 void nmethod::copy_scopes_data(u_char* buffer, int size) {
1777   assert(scopes_data_size() >= size, "oob");
1778   memcpy(scopes_data_begin(), buffer, size);
1779 }
1780 
1781 #ifdef ASSERT
1782 static PcDesc* linear_search(const PcDescSearch& search, int pc_offset, bool approximate) {
1783   PcDesc* lower = search.scopes_pcs_begin();
1784   PcDesc* upper = search.scopes_pcs_end();
1785   lower += 1; // exclude initial sentinel
1786   PcDesc* res = NULL;
1787   for (PcDesc* p = lower; p < upper; p++) {
1788     NOT_PRODUCT(--pc_nmethod_stats.pc_desc_tests);  // don't count this call to match_desc
1789     if (match_desc(p, pc_offset, approximate)) {
1790       if (res == NULL)
1791         res = p;
1792       else
1793         res = (PcDesc*) badAddress;
1794     }
1795   }
1796   return res;
1797 }
1798 #endif
1799 
1800 
1801 // Finds a PcDesc with real-pc equal to "pc"
1802 PcDesc* PcDescContainer::find_pc_desc_internal(address pc, bool approximate, const PcDescSearch& search) {
1803   address base_address = search.code_begin();
1804   if ((pc < base_address) ||
1805       (pc - base_address) >= (ptrdiff_t) PcDesc::upper_offset_limit) {
1806     return NULL;  // PC is wildly out of range
1807   }
1808   int pc_offset = (int) (pc - base_address);
1809 
1810   // Check the PcDesc cache if it contains the desired PcDesc
1811   // (This as an almost 100% hit rate.)
1812   PcDesc* res = _pc_desc_cache.find_pc_desc(pc_offset, approximate);
1813   if (res != NULL) {
1814     assert(res == linear_search(search, pc_offset, approximate), "cache ok");
1815     return res;
1816   }
1817 
1818   // Fallback algorithm: quasi-linear search for the PcDesc
1819   // Find the last pc_offset less than the given offset.
1820   // The successor must be the required match, if there is a match at all.
1821   // (Use a fixed radix to avoid expensive affine pointer arithmetic.)
1822   PcDesc* lower = search.scopes_pcs_begin();
1823   PcDesc* upper = search.scopes_pcs_end();
1824   upper -= 1; // exclude final sentinel
1825   if (lower >= upper)  return NULL;  // native method; no PcDescs at all
1826 
1827 #define assert_LU_OK \
1828   /* invariant on lower..upper during the following search: */ \
1829   assert(lower->pc_offset() <  pc_offset, "sanity"); \
1830   assert(upper->pc_offset() >= pc_offset, "sanity")
1831   assert_LU_OK;
1832 
1833   // Use the last successful return as a split point.
1834   PcDesc* mid = _pc_desc_cache.last_pc_desc();
1835   NOT_PRODUCT(++pc_nmethod_stats.pc_desc_searches);
1836   if (mid->pc_offset() < pc_offset) {
1837     lower = mid;
1838   } else {
1839     upper = mid;
1840   }
1841 
1842   // Take giant steps at first (4096, then 256, then 16, then 1)
1843   const int LOG2_RADIX = 4 /*smaller steps in debug mode:*/ debug_only(-1);
1844   const int RADIX = (1 << LOG2_RADIX);
1845   for (int step = (1 << (LOG2_RADIX*3)); step > 1; step >>= LOG2_RADIX) {
1846     while ((mid = lower + step) < upper) {
1847       assert_LU_OK;
1848       NOT_PRODUCT(++pc_nmethod_stats.pc_desc_searches);
1849       if (mid->pc_offset() < pc_offset) {
1850         lower = mid;
1851       } else {
1852         upper = mid;
1853         break;
1854       }
1855     }
1856     assert_LU_OK;
1857   }
1858 
1859   // Sneak up on the value with a linear search of length ~16.
1860   while (true) {
1861     assert_LU_OK;
1862     mid = lower + 1;
1863     NOT_PRODUCT(++pc_nmethod_stats.pc_desc_searches);
1864     if (mid->pc_offset() < pc_offset) {
1865       lower = mid;
1866     } else {
1867       upper = mid;
1868       break;
1869     }
1870   }
1871 #undef assert_LU_OK
1872 
1873   if (match_desc(upper, pc_offset, approximate)) {
1874     assert(upper == linear_search(search, pc_offset, approximate), "search ok");
1875     _pc_desc_cache.add_pc_desc(upper);
1876     return upper;
1877   } else {
1878     assert(NULL == linear_search(search, pc_offset, approximate), "search ok");
1879     return NULL;
1880   }
1881 }
1882 
1883 
1884 void nmethod::check_all_dependencies(DepChange& changes) {
1885   // Checked dependencies are allocated into this ResourceMark
1886   ResourceMark rm;
1887 
1888   // Turn off dependency tracing while actually testing dependencies.
1889   NOT_PRODUCT( FlagSetting fs(TraceDependencies, false) );
1890 
1891   typedef ResourceHashtable<DependencySignature, int, &DependencySignature::hash,
1892                             &DependencySignature::equals, 11027> DepTable;
1893 
1894   DepTable* table = new DepTable();
1895 
1896   // Iterate over live nmethods and check dependencies of all nmethods that are not
1897   // marked for deoptimization. A particular dependency is only checked once.
1898   NMethodIterator iter;
1899   while(iter.next()) {
1900     nmethod* nm = iter.method();
1901     // Only notify for live nmethods
1902     if (nm->is_alive() && !nm->is_marked_for_deoptimization()) {
1903       for (Dependencies::DepStream deps(nm); deps.next(); ) {
1904         // Construct abstraction of a dependency.
1905         DependencySignature* current_sig = new DependencySignature(deps);
1906 
1907         // Determine if dependency is already checked. table->put(...) returns
1908         // 'true' if the dependency is added (i.e., was not in the hashtable).
1909         if (table->put(*current_sig, 1)) {
1910           if (deps.check_dependency() != NULL) {
1911             // Dependency checking failed. Print out information about the failed
1912             // dependency and finally fail with an assert. We can fail here, since
1913             // dependency checking is never done in a product build.
1914             tty->print_cr("Failed dependency:");
1915             changes.print();
1916             nm->print();
1917             nm->print_dependencies();
1918             assert(false, "Should have been marked for deoptimization");
1919           }
1920         }
1921       }
1922     }
1923   }
1924 }
1925 
1926 bool nmethod::check_dependency_on(DepChange& changes) {
1927   // What has happened:
1928   // 1) a new class dependee has been added
1929   // 2) dependee and all its super classes have been marked
1930   bool found_check = false;  // set true if we are upset
1931   for (Dependencies::DepStream deps(this); deps.next(); ) {
1932     // Evaluate only relevant dependencies.
1933     if (deps.spot_check_dependency_at(changes) != NULL) {
1934       found_check = true;
1935       NOT_DEBUG(break);
1936     }
1937   }
1938   return found_check;
1939 }
1940 
1941 bool nmethod::is_evol_dependent_on(Klass* dependee) {
1942   InstanceKlass *dependee_ik = InstanceKlass::cast(dependee);
1943   Array<Method*>* dependee_methods = dependee_ik->methods();
1944   for (Dependencies::DepStream deps(this); deps.next(); ) {
1945     if (deps.type() == Dependencies::evol_method) {
1946       Method* method = deps.method_argument(0);
1947       for (int j = 0; j < dependee_methods->length(); j++) {
1948         if (dependee_methods->at(j) == method) {
1949           if (log_is_enabled(Debug, redefine, class, nmethod)) {
1950             ResourceMark rm;
1951             log_debug(redefine, class, nmethod)
1952               ("Found evol dependency of nmethod %s.%s(%s) compile_id=%d on method %s.%s(%s)",
1953                _method->method_holder()->external_name(),
1954                _method->name()->as_C_string(),
1955                _method->signature()->as_C_string(),
1956                compile_id(),
1957                method->method_holder()->external_name(),
1958                method->name()->as_C_string(),
1959                method->signature()->as_C_string());
1960           }
1961           if (TraceDependencies || LogCompilation)
1962             deps.log_dependency(dependee);
1963           return true;
1964         }
1965       }
1966     }
1967   }
1968   return false;
1969 }
1970 
1971 // Called from mark_for_deoptimization, when dependee is invalidated.
1972 bool nmethod::is_dependent_on_method(Method* dependee) {
1973   for (Dependencies::DepStream deps(this); deps.next(); ) {
1974     if (deps.type() != Dependencies::evol_method)
1975       continue;
1976     Method* method = deps.method_argument(0);
1977     if (method == dependee) return true;
1978   }
1979   return false;
1980 }
1981 
1982 
1983 bool nmethod::is_patchable_at(address instr_addr) {
1984   assert(insts_contains(instr_addr), "wrong nmethod used");
1985   if (is_zombie()) {
1986     // a zombie may never be patched
1987     return false;
1988   }
1989   return true;
1990 }
1991 
1992 
1993 address nmethod::continuation_for_implicit_exception(address pc) {
1994   // Exception happened outside inline-cache check code => we are inside
1995   // an active nmethod => use cpc to determine a return address
1996   int exception_offset = pc - code_begin();
1997   int cont_offset = ImplicitExceptionTable(this).at( exception_offset );
1998 #ifdef ASSERT
1999   if (cont_offset == 0) {
2000     Thread* thread = Thread::current();
2001     ResetNoHandleMark rnm; // Might be called from LEAF/QUICK ENTRY
2002     HandleMark hm(thread);
2003     ResourceMark rm(thread);
2004     CodeBlob* cb = CodeCache::find_blob(pc);
2005     assert(cb != NULL && cb == this, "");
2006     ttyLocker ttyl;
2007     tty->print_cr("implicit exception happened at " INTPTR_FORMAT, p2i(pc));
2008     print();
2009     method()->print_codes();
2010     print_code();
2011     print_pcs();
2012   }
2013 #endif
2014   if (cont_offset == 0) {
2015     // Let the normal error handling report the exception
2016     return NULL;
2017   }
2018   return code_begin() + cont_offset;
2019 }
2020 
2021 
2022 
2023 void nmethod_init() {
2024   // make sure you didn't forget to adjust the filler fields
2025   assert(sizeof(nmethod) % oopSize == 0, "nmethod size must be multiple of a word");
2026 }
2027 
2028 
2029 //-------------------------------------------------------------------------------------------
2030 
2031 
2032 // QQQ might we make this work from a frame??
2033 nmethodLocker::nmethodLocker(address pc) {
2034   CodeBlob* cb = CodeCache::find_blob(pc);
2035   guarantee(cb != NULL && cb->is_compiled(), "bad pc for a nmethod found");
2036   _nm = cb->as_compiled_method();
2037   lock_nmethod(_nm);
2038 }
2039 
2040 // Only JvmtiDeferredEvent::compiled_method_unload_event()
2041 // should pass zombie_ok == true.
2042 void nmethodLocker::lock_nmethod(CompiledMethod* cm, bool zombie_ok) {
2043   if (cm == NULL)  return;
2044   if (cm->is_aot()) return;  // FIXME: Revisit once _lock_count is added to aot_method
2045   nmethod* nm = cm->as_nmethod();
2046   Atomic::inc(&nm->_lock_count);
2047   assert(zombie_ok || !nm->is_zombie(), "cannot lock a zombie method");
2048 }
2049 
2050 void nmethodLocker::unlock_nmethod(CompiledMethod* cm) {
2051   if (cm == NULL)  return;
2052   if (cm->is_aot()) return;  // FIXME: Revisit once _lock_count is added to aot_method
2053   nmethod* nm = cm->as_nmethod();
2054   Atomic::dec(&nm->_lock_count);
2055   assert(nm->_lock_count >= 0, "unmatched nmethod lock/unlock");
2056 }
2057 
2058 
2059 // -----------------------------------------------------------------------------
2060 // Verification
2061 
2062 class VerifyOopsClosure: public OopClosure {
2063   nmethod* _nm;
2064   bool     _ok;
2065 public:
2066   VerifyOopsClosure(nmethod* nm) : _nm(nm), _ok(true) { }
2067   bool ok() { return _ok; }
2068   virtual void do_oop(oop* p) {
2069     if (oopDesc::is_oop_or_null(*p)) return;
2070     if (_ok) {
2071       _nm->print_nmethod(true);
2072       _ok = false;
2073     }
2074     tty->print_cr("*** non-oop " PTR_FORMAT " found at " PTR_FORMAT " (offset %d)",
2075                   p2i(*p), p2i(p), (int)((intptr_t)p - (intptr_t)_nm));
2076   }
2077   virtual void do_oop(narrowOop* p) { ShouldNotReachHere(); }
2078 };
2079 
2080 void nmethod::verify() {
2081 
2082   // Hmm. OSR methods can be deopted but not marked as zombie or not_entrant
2083   // seems odd.
2084 
2085   if (is_zombie() || is_not_entrant() || is_unloaded())
2086     return;
2087 
2088   // Make sure all the entry points are correctly aligned for patching.
2089   NativeJump::check_verified_entry_alignment(entry_point(), verified_entry_point());
2090 
2091   // assert(oopDesc::is_oop(method()), "must be valid");
2092 
2093   ResourceMark rm;
2094 
2095   if (!CodeCache::contains(this)) {
2096     fatal("nmethod at " INTPTR_FORMAT " not in zone", p2i(this));
2097   }
2098 
2099   if(is_native_method() )
2100     return;
2101 
2102   nmethod* nm = CodeCache::find_nmethod(verified_entry_point());
2103   if (nm != this) {
2104     fatal("findNMethod did not find this nmethod (" INTPTR_FORMAT ")", p2i(this));
2105   }
2106 
2107   for (PcDesc* p = scopes_pcs_begin(); p < scopes_pcs_end(); p++) {
2108     if (! p->verify(this)) {
2109       tty->print_cr("\t\tin nmethod at " INTPTR_FORMAT " (pcs)", p2i(this));
2110     }
2111   }
2112 
2113   VerifyOopsClosure voc(this);
2114   oops_do(&voc);
2115   assert(voc.ok(), "embedded oops must be OK");
2116   Universe::heap()->verify_nmethod(this);
2117 
2118   verify_scopes();
2119 }
2120 
2121 
2122 void nmethod::verify_interrupt_point(address call_site) {
2123   // Verify IC only when nmethod installation is finished.
2124   bool is_installed = (method()->code() == this) // nmethod is in state 'in_use' and installed
2125                       || !this->is_in_use();     // nmethod is installed, but not in 'in_use' state
2126   if (is_installed) {
2127     Thread *cur = Thread::current();
2128     if (CompiledIC_lock->owner() == cur ||
2129         ((cur->is_VM_thread() || cur->is_ConcurrentGC_thread()) &&
2130          SafepointSynchronize::is_at_safepoint())) {
2131       CompiledIC_at(this, call_site);
2132       CHECK_UNHANDLED_OOPS_ONLY(Thread::current()->clear_unhandled_oops());
2133     } else {
2134       MutexLocker ml_verify (CompiledIC_lock);
2135       CompiledIC_at(this, call_site);
2136     }
2137   }
2138 
2139   PcDesc* pd = pc_desc_at(nativeCall_at(call_site)->return_address());
2140   assert(pd != NULL, "PcDesc must exist");
2141   for (ScopeDesc* sd = new ScopeDesc(this, pd->scope_decode_offset(),
2142                                      pd->obj_decode_offset(), pd->should_reexecute(), pd->rethrow_exception(),
2143                                      pd->return_oop());
2144        !sd->is_top(); sd = sd->sender()) {
2145     sd->verify();
2146   }
2147 }
2148 
2149 void nmethod::verify_scopes() {
2150   if( !method() ) return;       // Runtime stubs have no scope
2151   if (method()->is_native()) return; // Ignore stub methods.
2152   // iterate through all interrupt point
2153   // and verify the debug information is valid.
2154   RelocIterator iter((nmethod*)this);
2155   while (iter.next()) {
2156     address stub = NULL;
2157     switch (iter.type()) {
2158       case relocInfo::virtual_call_type:
2159         verify_interrupt_point(iter.addr());
2160         break;
2161       case relocInfo::opt_virtual_call_type:
2162         stub = iter.opt_virtual_call_reloc()->static_stub(false);
2163         verify_interrupt_point(iter.addr());
2164         break;
2165       case relocInfo::static_call_type:
2166         stub = iter.static_call_reloc()->static_stub(false);
2167         //verify_interrupt_point(iter.addr());
2168         break;
2169       case relocInfo::runtime_call_type:
2170       case relocInfo::runtime_call_w_cp_type: {
2171         address destination = iter.reloc()->value();
2172         // Right now there is no way to find out which entries support
2173         // an interrupt point.  It would be nice if we had this
2174         // information in a table.
2175         break;
2176       }
2177       default:
2178         break;
2179     }
2180     assert(stub == NULL || stub_contains(stub), "static call stub outside stub section");
2181   }
2182 }
2183 
2184 
2185 // -----------------------------------------------------------------------------
2186 // Non-product code
2187 #ifndef PRODUCT
2188 
2189 class DebugScavengeRoot: public OopClosure {
2190   nmethod* _nm;
2191   bool     _ok;
2192 public:
2193   DebugScavengeRoot(nmethod* nm) : _nm(nm), _ok(true) { }
2194   bool ok() { return _ok; }
2195   virtual void do_oop(oop* p) {
2196     if ((*p) == NULL || !(*p)->is_scavengable())  return;
2197     if (_ok) {
2198       _nm->print_nmethod(true);
2199       _ok = false;
2200     }
2201     tty->print_cr("*** scavengable oop " PTR_FORMAT " found at " PTR_FORMAT " (offset %d)",
2202                   p2i(*p), p2i(p), (int)((intptr_t)p - (intptr_t)_nm));
2203     (*p)->print();
2204   }
2205   virtual void do_oop(narrowOop* p) { ShouldNotReachHere(); }
2206 };
2207 
2208 void nmethod::verify_scavenge_root_oops() {
2209   if (!on_scavenge_root_list()) {
2210     // Actually look inside, to verify the claim that it's clean.
2211     DebugScavengeRoot debug_scavenge_root(this);
2212     oops_do(&debug_scavenge_root);
2213     if (!debug_scavenge_root.ok())
2214       fatal("found an unadvertised bad scavengable oop in the code cache");
2215   }
2216   assert(scavenge_root_not_marked(), "");
2217 }
2218 
2219 #endif // PRODUCT
2220 
2221 // Printing operations
2222 
2223 void nmethod::print() const {
2224   ResourceMark rm;
2225   ttyLocker ttyl;   // keep the following output all in one block
2226 
2227   tty->print("Compiled method ");
2228 
2229   if (is_compiled_by_c1()) {
2230     tty->print("(c1) ");
2231   } else if (is_compiled_by_c2()) {
2232     tty->print("(c2) ");


2233   } else if (is_compiled_by_jvmci()) {
2234     tty->print("(JVMCI) ");
2235   } else {
2236     tty->print("(nm) ");
2237   }
2238 
2239   print_on(tty, NULL);
2240 
2241   if (WizardMode) {
2242     tty->print("((nmethod*) " INTPTR_FORMAT ") ", p2i(this));
2243     tty->print(" for method " INTPTR_FORMAT , p2i(method()));
2244     tty->print(" { ");
2245     tty->print_cr("%s ", state());
2246     if (on_scavenge_root_list())  tty->print("scavenge_root ");
2247     tty->print_cr("}:");
2248   }
2249   if (size              () > 0) tty->print_cr(" total in heap  [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
2250                                               p2i(this),
2251                                               p2i(this) + size(),
2252                                               size());
2253   if (relocation_size   () > 0) tty->print_cr(" relocation     [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
2254                                               p2i(relocation_begin()),
2255                                               p2i(relocation_end()),
2256                                               relocation_size());
2257   if (consts_size       () > 0) tty->print_cr(" constants      [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
2258                                               p2i(consts_begin()),
2259                                               p2i(consts_end()),
2260                                               consts_size());
2261   if (insts_size        () > 0) tty->print_cr(" main code      [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
2262                                               p2i(insts_begin()),
2263                                               p2i(insts_end()),
2264                                               insts_size());
2265   if (stub_size         () > 0) tty->print_cr(" stub code      [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
2266                                               p2i(stub_begin()),
2267                                               p2i(stub_end()),
2268                                               stub_size());
2269   if (oops_size         () > 0) tty->print_cr(" oops           [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
2270                                               p2i(oops_begin()),
2271                                               p2i(oops_end()),
2272                                               oops_size());
2273   if (metadata_size      () > 0) tty->print_cr(" metadata       [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
2274                                               p2i(metadata_begin()),
2275                                               p2i(metadata_end()),
2276                                               metadata_size());
2277   if (scopes_data_size  () > 0) tty->print_cr(" scopes data    [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
2278                                               p2i(scopes_data_begin()),
2279                                               p2i(scopes_data_end()),
2280                                               scopes_data_size());
2281   if (scopes_pcs_size   () > 0) tty->print_cr(" scopes pcs     [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
2282                                               p2i(scopes_pcs_begin()),
2283                                               p2i(scopes_pcs_end()),
2284                                               scopes_pcs_size());
2285   if (dependencies_size () > 0) tty->print_cr(" dependencies   [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
2286                                               p2i(dependencies_begin()),
2287                                               p2i(dependencies_end()),
2288                                               dependencies_size());
2289   if (handler_table_size() > 0) tty->print_cr(" handler table  [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
2290                                               p2i(handler_table_begin()),
2291                                               p2i(handler_table_end()),
2292                                               handler_table_size());
2293   if (nul_chk_table_size() > 0) tty->print_cr(" nul chk table  [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
2294                                               p2i(nul_chk_table_begin()),
2295                                               p2i(nul_chk_table_end()),
2296                                               nul_chk_table_size());
2297 }
2298 
2299 #ifndef PRODUCT
2300 
2301 void nmethod::print_scopes() {
2302   // Find the first pc desc for all scopes in the code and print it.
2303   ResourceMark rm;
2304   for (PcDesc* p = scopes_pcs_begin(); p < scopes_pcs_end(); p++) {
2305     if (p->scope_decode_offset() == DebugInformationRecorder::serialized_null)
2306       continue;
2307 
2308     ScopeDesc* sd = scope_desc_at(p->real_pc(this));
2309     while (sd != NULL) {
2310       sd->print_on(tty, p);
2311       sd = sd->sender();
2312     }
2313   }
2314 }
2315 
2316 void nmethod::print_dependencies() {
2317   ResourceMark rm;
2318   ttyLocker ttyl;   // keep the following output all in one block
2319   tty->print_cr("Dependencies:");
2320   for (Dependencies::DepStream deps(this); deps.next(); ) {
2321     deps.print_dependency();
2322     Klass* ctxk = deps.context_type();
2323     if (ctxk != NULL) {
2324       if (ctxk->is_instance_klass() && InstanceKlass::cast(ctxk)->is_dependent_nmethod(this)) {
2325         tty->print_cr("   [nmethod<=klass]%s", ctxk->external_name());
2326       }
2327     }
2328     deps.log_dependency();  // put it into the xml log also
2329   }
2330 }
2331 
2332 
2333 void nmethod::print_relocations() {
2334   ResourceMark m;       // in case methods get printed via the debugger
2335   tty->print_cr("relocations:");
2336   RelocIterator iter(this);
2337   iter.print();
2338 }
2339 
2340 
2341 void nmethod::print_pcs() {
2342   ResourceMark m;       // in case methods get printed via debugger
2343   tty->print_cr("pc-bytecode offsets:");
2344   for (PcDesc* p = scopes_pcs_begin(); p < scopes_pcs_end(); p++) {
2345     p->print(this);
2346   }
2347 }
2348 
2349 void nmethod::print_recorded_oops() {
2350   tty->print_cr("Recorded oops:");
2351   for (int i = 0; i < oops_count(); i++) {
2352     oop o = oop_at(i);
2353     tty->print("#%3d: " INTPTR_FORMAT " ", i, p2i(o));
2354     if (o == (oop)Universe::non_oop_word()) {
2355       tty->print("non-oop word");
2356     } else {
2357       o->print_value();
2358     }
2359     tty->cr();
2360   }
2361 }
2362 
2363 void nmethod::print_recorded_metadata() {
2364   tty->print_cr("Recorded metadata:");
2365   for (int i = 0; i < metadata_count(); i++) {
2366     Metadata* m = metadata_at(i);
2367     tty->print("#%3d: " INTPTR_FORMAT " ", i, p2i(m));
2368     if (m == (Metadata*)Universe::non_oop_word()) {
2369       tty->print("non-metadata word");
2370     } else {
2371       m->print_value_on_maybe_null(tty);
2372     }
2373     tty->cr();
2374   }
2375 }
2376 
2377 #endif // PRODUCT
2378 
2379 const char* nmethod::reloc_string_for(u_char* begin, u_char* end) {
2380   RelocIterator iter(this, begin, end);
2381   bool have_one = false;
2382   while (iter.next()) {
2383     have_one = true;
2384     switch (iter.type()) {
2385         case relocInfo::none:                  return "no_reloc";
2386         case relocInfo::oop_type: {
2387           stringStream st;
2388           oop_Relocation* r = iter.oop_reloc();
2389           oop obj = r->oop_value();
2390           st.print("oop(");
2391           if (obj == NULL) st.print("NULL");
2392           else obj->print_value_on(&st);
2393           st.print(")");
2394           return st.as_string();
2395         }
2396         case relocInfo::metadata_type: {
2397           stringStream st;
2398           metadata_Relocation* r = iter.metadata_reloc();
2399           Metadata* obj = r->metadata_value();
2400           st.print("metadata(");
2401           if (obj == NULL) st.print("NULL");
2402           else obj->print_value_on(&st);
2403           st.print(")");
2404           return st.as_string();
2405         }
2406         case relocInfo::runtime_call_type:
2407         case relocInfo::runtime_call_w_cp_type: {
2408           stringStream st;
2409           st.print("runtime_call");
2410           CallRelocation* r = (CallRelocation*)iter.reloc();
2411           address dest = r->destination();
2412           CodeBlob* cb = CodeCache::find_blob(dest);
2413           if (cb != NULL) {
2414             st.print(" %s", cb->name());
2415           } else {
2416             ResourceMark rm;
2417             const int buflen = 1024;
2418             char* buf = NEW_RESOURCE_ARRAY(char, buflen);
2419             int offset;
2420             if (os::dll_address_to_function_name(dest, buf, buflen, &offset)) {
2421               st.print(" %s", buf);
2422               if (offset != 0) {
2423                 st.print("+%d", offset);
2424               }
2425             }
2426           }
2427           return st.as_string();
2428         }
2429         case relocInfo::virtual_call_type: {
2430           stringStream st;
2431           st.print_raw("virtual_call");
2432           virtual_call_Relocation* r = iter.virtual_call_reloc();
2433           Method* m = r->method_value();
2434           if (m != NULL) {
2435             assert(m->is_method(), "");
2436             m->print_short_name(&st);
2437           }
2438           return st.as_string();
2439         }
2440         case relocInfo::opt_virtual_call_type: {
2441           stringStream st;
2442           st.print_raw("optimized virtual_call");
2443           opt_virtual_call_Relocation* r = iter.opt_virtual_call_reloc();
2444           Method* m = r->method_value();
2445           if (m != NULL) {
2446             assert(m->is_method(), "");
2447             m->print_short_name(&st);
2448           }
2449           return st.as_string();
2450         }
2451         case relocInfo::static_call_type: {
2452           stringStream st;
2453           st.print_raw("static_call");
2454           static_call_Relocation* r = iter.static_call_reloc();
2455           Method* m = r->method_value();
2456           if (m != NULL) {
2457             assert(m->is_method(), "");
2458             m->print_short_name(&st);
2459           }
2460           return st.as_string();
2461         }
2462         case relocInfo::static_stub_type:      return "static_stub";
2463         case relocInfo::external_word_type:    return "external_word";
2464         case relocInfo::internal_word_type:    return "internal_word";
2465         case relocInfo::section_word_type:     return "section_word";
2466         case relocInfo::poll_type:             return "poll";
2467         case relocInfo::poll_return_type:      return "poll_return";
2468         case relocInfo::type_mask:             return "type_bit_mask";
2469 
2470         default:
2471           break;
2472     }
2473   }
2474   return have_one ? "other" : NULL;
2475 }
2476 
2477 // Return a the last scope in (begin..end]
2478 ScopeDesc* nmethod::scope_desc_in(address begin, address end) {
2479   PcDesc* p = pc_desc_near(begin+1);
2480   if (p != NULL && p->real_pc(this) <= end) {
2481     return new ScopeDesc(this, p->scope_decode_offset(),
2482                          p->obj_decode_offset(), p->should_reexecute(), p->rethrow_exception(),
2483                          p->return_oop());
2484   }
2485   return NULL;
2486 }
2487 
2488 void nmethod::print_nmethod_labels(outputStream* stream, address block_begin) const {
2489   if (block_begin == entry_point())             stream->print_cr("[Entry Point]");
2490   if (block_begin == verified_entry_point())    stream->print_cr("[Verified Entry Point]");
2491   if (JVMCI_ONLY(_exception_offset >= 0 &&) block_begin == exception_begin())         stream->print_cr("[Exception Handler]");
2492   if (block_begin == stub_begin())              stream->print_cr("[Stub Code]");
2493   if (JVMCI_ONLY(_deopt_handler_begin != NULL &&) block_begin == deopt_handler_begin())     stream->print_cr("[Deopt Handler Code]");
2494 
2495   if (has_method_handle_invokes())
2496     if (block_begin == deopt_mh_handler_begin())  stream->print_cr("[Deopt MH Handler Code]");
2497 
2498   if (block_begin == consts_begin())            stream->print_cr("[Constants]");
2499 
2500   if (block_begin == entry_point()) {
2501     methodHandle m = method();
2502     if (m.not_null()) {
2503       stream->print("  # ");
2504       m->print_value_on(stream);
2505       stream->cr();
2506     }
2507     if (m.not_null() && !is_osr_method()) {
2508       ResourceMark rm;
2509       int sizeargs = m->size_of_parameters();
2510       BasicType* sig_bt = NEW_RESOURCE_ARRAY(BasicType, sizeargs);
2511       VMRegPair* regs   = NEW_RESOURCE_ARRAY(VMRegPair, sizeargs);
2512       {
2513         int sig_index = 0;
2514         if (!m->is_static())
2515           sig_bt[sig_index++] = T_OBJECT; // 'this'
2516         for (SignatureStream ss(m->signature()); !ss.at_return_type(); ss.next()) {
2517           BasicType t = ss.type();
2518           sig_bt[sig_index++] = t;
2519           if (type2size[t] == 2) {
2520             sig_bt[sig_index++] = T_VOID;
2521           } else {
2522             assert(type2size[t] == 1, "size is 1 or 2");
2523           }
2524         }
2525         assert(sig_index == sizeargs, "");
2526       }
2527       const char* spname = "sp"; // make arch-specific?
2528       intptr_t out_preserve = SharedRuntime::java_calling_convention(sig_bt, regs, sizeargs, false);
2529       int stack_slot_offset = this->frame_size() * wordSize;
2530       int tab1 = 14, tab2 = 24;
2531       int sig_index = 0;
2532       int arg_index = (m->is_static() ? 0 : -1);
2533       bool did_old_sp = false;
2534       for (SignatureStream ss(m->signature()); !ss.at_return_type(); ) {
2535         bool at_this = (arg_index == -1);
2536         bool at_old_sp = false;
2537         BasicType t = (at_this ? T_OBJECT : ss.type());
2538         assert(t == sig_bt[sig_index], "sigs in sync");
2539         if (at_this)
2540           stream->print("  # this: ");
2541         else
2542           stream->print("  # parm%d: ", arg_index);
2543         stream->move_to(tab1);
2544         VMReg fst = regs[sig_index].first();
2545         VMReg snd = regs[sig_index].second();
2546         if (fst->is_reg()) {
2547           stream->print("%s", fst->name());
2548           if (snd->is_valid())  {
2549             stream->print(":%s", snd->name());
2550           }
2551         } else if (fst->is_stack()) {
2552           int offset = fst->reg2stack() * VMRegImpl::stack_slot_size + stack_slot_offset;
2553           if (offset == stack_slot_offset)  at_old_sp = true;
2554           stream->print("[%s+0x%x]", spname, offset);
2555         } else {
2556           stream->print("reg%d:%d??", (int)(intptr_t)fst, (int)(intptr_t)snd);
2557         }
2558         stream->print(" ");
2559         stream->move_to(tab2);
2560         stream->print("= ");
2561         if (at_this) {
2562           m->method_holder()->print_value_on(stream);
2563         } else {
2564           bool did_name = false;
2565           if (!at_this && ss.is_object()) {
2566             Symbol* name = ss.as_symbol_or_null();
2567             if (name != NULL) {
2568               name->print_value_on(stream);
2569               did_name = true;
2570             }
2571           }
2572           if (!did_name)
2573             stream->print("%s", type2name(t));
2574         }
2575         if (at_old_sp) {
2576           stream->print("  (%s of caller)", spname);
2577           did_old_sp = true;
2578         }
2579         stream->cr();
2580         sig_index += type2size[t];
2581         arg_index += 1;
2582         if (!at_this)  ss.next();
2583       }
2584       if (!did_old_sp) {
2585         stream->print("  # ");
2586         stream->move_to(tab1);
2587         stream->print("[%s+0x%x]", spname, stack_slot_offset);
2588         stream->print("  (%s of caller)", spname);
2589         stream->cr();
2590       }
2591     }
2592   }
2593 }
2594 
2595 void nmethod::print_code_comment_on(outputStream* st, int column, u_char* begin, u_char* end) {
2596   // First, find an oopmap in (begin, end].
2597   // We use the odd half-closed interval so that oop maps and scope descs
2598   // which are tied to the byte after a call are printed with the call itself.
2599   address base = code_begin();
2600   ImmutableOopMapSet* oms = oop_maps();
2601   if (oms != NULL) {
2602     for (int i = 0, imax = oms->count(); i < imax; i++) {
2603       const ImmutableOopMapPair* pair = oms->pair_at(i);
2604       const ImmutableOopMap* om = pair->get_from(oms);
2605       address pc = base + pair->pc_offset();
2606       if (pc > begin) {
2607         if (pc <= end) {
2608           st->move_to(column);
2609           st->print("; ");
2610           om->print_on(st);
2611         }
2612         break;
2613       }
2614     }
2615   }
2616 
2617   // Print any debug info present at this pc.
2618   ScopeDesc* sd  = scope_desc_in(begin, end);
2619   if (sd != NULL) {
2620     st->move_to(column);
2621     if (sd->bci() == SynchronizationEntryBCI) {
2622       st->print(";*synchronization entry");
2623     } else {
2624       if (sd->method() == NULL) {
2625         st->print("method is NULL");
2626       } else if (sd->method()->is_native()) {
2627         st->print("method is native");
2628       } else {
2629         Bytecodes::Code bc = sd->method()->java_code_at(sd->bci());
2630         st->print(";*%s", Bytecodes::name(bc));
2631         switch (bc) {
2632         case Bytecodes::_invokevirtual:
2633         case Bytecodes::_invokespecial:
2634         case Bytecodes::_invokestatic:
2635         case Bytecodes::_invokeinterface:
2636           {
2637             Bytecode_invoke invoke(sd->method(), sd->bci());
2638             st->print(" ");
2639             if (invoke.name() != NULL)
2640               invoke.name()->print_symbol_on(st);
2641             else
2642               st->print("<UNKNOWN>");
2643             break;
2644           }
2645         case Bytecodes::_getfield:
2646         case Bytecodes::_putfield:
2647         case Bytecodes::_getstatic:
2648         case Bytecodes::_putstatic:
2649           {
2650             Bytecode_field field(sd->method(), sd->bci());
2651             st->print(" ");
2652             if (field.name() != NULL)
2653               field.name()->print_symbol_on(st);
2654             else
2655               st->print("<UNKNOWN>");
2656           }
2657         default:
2658           break;
2659         }
2660       }
2661       st->print(" {reexecute=%d rethrow=%d return_oop=%d}", sd->should_reexecute(), sd->rethrow_exception(), sd->return_oop());
2662     }
2663 
2664     // Print all scopes
2665     for (;sd != NULL; sd = sd->sender()) {
2666       st->move_to(column);
2667       st->print("; -");
2668       if (sd->method() == NULL) {
2669         st->print("method is NULL");
2670       } else {
2671         sd->method()->print_short_name(st);
2672       }
2673       int lineno = sd->method()->line_number_from_bci(sd->bci());
2674       if (lineno != -1) {
2675         st->print("@%d (line %d)", sd->bci(), lineno);
2676       } else {
2677         st->print("@%d", sd->bci());
2678       }
2679       st->cr();
2680     }
2681   }
2682 
2683   // Print relocation information
2684   const char* str = reloc_string_for(begin, end);
2685   if (str != NULL) {
2686     if (sd != NULL) st->cr();
2687     st->move_to(column);
2688     st->print(";   {%s}", str);
2689   }
2690   int cont_offset = ImplicitExceptionTable(this).at(begin - code_begin());
2691   if (cont_offset != 0) {
2692     st->move_to(column);
2693     st->print("; implicit exception: dispatches to " INTPTR_FORMAT, p2i(code_begin() + cont_offset));
2694   }
2695 
2696 }
2697 
2698 class DirectNativeCallWrapper: public NativeCallWrapper {
2699 private:
2700   NativeCall* _call;
2701 
2702 public:
2703   DirectNativeCallWrapper(NativeCall* call) : _call(call) {}
2704 
2705   virtual address destination() const { return _call->destination(); }
2706   virtual address instruction_address() const { return _call->instruction_address(); }
2707   virtual address next_instruction_address() const { return _call->next_instruction_address(); }
2708   virtual address return_address() const { return _call->return_address(); }
2709 
2710   virtual address get_resolve_call_stub(bool is_optimized) const {
2711     if (is_optimized) {
2712       return SharedRuntime::get_resolve_opt_virtual_call_stub();
2713     }
2714     return SharedRuntime::get_resolve_virtual_call_stub();
2715   }
2716 
2717   virtual void set_destination_mt_safe(address dest) {
2718 #if INCLUDE_AOT
2719     if (UseAOT) {
2720       CodeBlob* callee = CodeCache::find_blob(dest);
2721       CompiledMethod* cm = callee->as_compiled_method_or_null();
2722       if (cm != NULL && cm->is_far_code()) {
2723         // Temporary fix, see JDK-8143106
2724         CompiledDirectStaticCall* csc = CompiledDirectStaticCall::at(instruction_address());
2725         csc->set_to_far(methodHandle(cm->method()), dest);
2726         return;
2727       }
2728     }
2729 #endif
2730     _call->set_destination_mt_safe(dest);
2731   }
2732 
2733   virtual void set_to_interpreted(const methodHandle& method, CompiledICInfo& info) {
2734     CompiledDirectStaticCall* csc = CompiledDirectStaticCall::at(instruction_address());
2735 #if INCLUDE_AOT
2736     if (info.to_aot()) {
2737       csc->set_to_far(method, info.entry());
2738     } else
2739 #endif
2740     {
2741       csc->set_to_interpreted(method, info.entry());
2742     }
2743   }
2744 
2745   virtual void verify() const {
2746     // make sure code pattern is actually a call imm32 instruction
2747     _call->verify();
2748     if (os::is_MP()) {
2749       _call->verify_alignment();
2750     }
2751   }
2752 
2753   virtual void verify_resolve_call(address dest) const {
2754     CodeBlob* db = CodeCache::find_blob_unsafe(dest);
2755     assert(!db->is_adapter_blob(), "must use stub!");
2756   }
2757 
2758   virtual bool is_call_to_interpreted(address dest) const {
2759     CodeBlob* cb = CodeCache::find_blob(_call->instruction_address());
2760     return cb->contains(dest);
2761   }
2762 
2763   virtual bool is_safe_for_patching() const { return false; }
2764 
2765   virtual NativeInstruction* get_load_instruction(virtual_call_Relocation* r) const {
2766     return nativeMovConstReg_at(r->cached_value());
2767   }
2768 
2769   virtual void *get_data(NativeInstruction* instruction) const {
2770     return (void*)((NativeMovConstReg*) instruction)->data();
2771   }
2772 
2773   virtual void set_data(NativeInstruction* instruction, intptr_t data) {
2774     ((NativeMovConstReg*) instruction)->set_data(data);
2775   }
2776 };
2777 
2778 NativeCallWrapper* nmethod::call_wrapper_at(address call) const {
2779   return new DirectNativeCallWrapper((NativeCall*) call);
2780 }
2781 
2782 NativeCallWrapper* nmethod::call_wrapper_before(address return_pc) const {
2783   return new DirectNativeCallWrapper(nativeCall_before(return_pc));
2784 }
2785 
2786 address nmethod::call_instruction_address(address pc) const {
2787   if (NativeCall::is_call_before(pc)) {
2788     NativeCall *ncall = nativeCall_before(pc);
2789     return ncall->instruction_address();
2790   }
2791   return NULL;
2792 }
2793 
2794 CompiledStaticCall* nmethod::compiledStaticCall_at(Relocation* call_site) const {
2795   return CompiledDirectStaticCall::at(call_site);
2796 }
2797 
2798 CompiledStaticCall* nmethod::compiledStaticCall_at(address call_site) const {
2799   return CompiledDirectStaticCall::at(call_site);
2800 }
2801 
2802 CompiledStaticCall* nmethod::compiledStaticCall_before(address return_addr) const {
2803   return CompiledDirectStaticCall::before(return_addr);
2804 }
2805 
2806 #ifndef PRODUCT
2807 
2808 void nmethod::print_value_on(outputStream* st) const {
2809   st->print("nmethod");
2810   print_on(st, NULL);
2811 }
2812 
2813 void nmethod::print_calls(outputStream* st) {
2814   RelocIterator iter(this);
2815   while (iter.next()) {
2816     switch (iter.type()) {
2817     case relocInfo::virtual_call_type:
2818     case relocInfo::opt_virtual_call_type: {
2819       VerifyMutexLocker mc(CompiledIC_lock);
2820       CompiledIC_at(&iter)->print();
2821       break;
2822     }
2823     case relocInfo::static_call_type:
2824       st->print_cr("Static call at " INTPTR_FORMAT, p2i(iter.reloc()->addr()));
2825       CompiledDirectStaticCall::at(iter.reloc())->print();
2826       break;
2827     default:
2828       break;
2829     }
2830   }
2831 }
2832 
2833 void nmethod::print_handler_table() {
2834   ExceptionHandlerTable(this).print();
2835 }
2836 
2837 void nmethod::print_nul_chk_table() {
2838   ImplicitExceptionTable(this).print(code_begin());
2839 }
2840 
2841 void nmethod::print_statistics() {
2842   ttyLocker ttyl;
2843   if (xtty != NULL)  xtty->head("statistics type='nmethod'");
2844   native_nmethod_stats.print_native_nmethod_stats();
2845 #ifdef COMPILER1
2846   c1_java_nmethod_stats.print_nmethod_stats("C1");
2847 #endif
2848 #ifdef COMPILER2
2849   c2_java_nmethod_stats.print_nmethod_stats("C2");
2850 #endif
2851 #if INCLUDE_JVMCI
2852   jvmci_java_nmethod_stats.print_nmethod_stats("JVMCI");



2853 #endif
2854   unknown_java_nmethod_stats.print_nmethod_stats("Unknown");
2855   DebugInformationRecorder::print_statistics();
2856 #ifndef PRODUCT
2857   pc_nmethod_stats.print_pc_stats();
2858 #endif
2859   Dependencies::print_statistics();
2860   if (xtty != NULL)  xtty->tail("statistics");
2861 }
2862 
2863 #endif // !PRODUCT
2864 
2865 #if INCLUDE_JVMCI
2866 void nmethod::clear_jvmci_installed_code() {
2867   // write_ref_method_pre/post can only be safely called at a
2868   // safepoint or while holding the CodeCache_lock
2869   assert(CodeCache_lock->is_locked() ||
2870          SafepointSynchronize::is_at_safepoint(), "should be performed under a lock for consistency");
2871   if (_jvmci_installed_code != NULL) {
2872     // This must be done carefully to maintain nmethod remembered sets properly
2873     BarrierSet* bs = Universe::heap()->barrier_set();
2874     bs->write_ref_nmethod_pre(&_jvmci_installed_code, this);
2875     _jvmci_installed_code = NULL;
2876     bs->write_ref_nmethod_post(&_jvmci_installed_code, this);
2877   }
2878 }
2879 
2880 void nmethod::maybe_invalidate_installed_code() {
2881   assert(Patching_lock->is_locked() ||
2882          SafepointSynchronize::is_at_safepoint(), "should be performed under a lock for consistency");
2883   oop installed_code = jvmci_installed_code();
2884   if (installed_code != NULL) {
2885     nmethod* nm = (nmethod*)InstalledCode::address(installed_code);
2886     if (nm == NULL || nm != this) {
2887       // The link has been broken or the InstalledCode instance is
2888       // associated with another nmethod so do nothing.
2889       return;
2890     }
2891     if (!is_alive()) {
2892       // Break the link between nmethod and InstalledCode such that the nmethod
2893       // can subsequently be flushed safely.  The link must be maintained while
2894       // the method could have live activations since invalidateInstalledCode
2895       // might want to invalidate all existing activations.
2896       InstalledCode::set_address(installed_code, 0);
2897       InstalledCode::set_entryPoint(installed_code, 0);
2898     } else if (is_not_entrant()) {
2899       // Remove the entry point so any invocation will fail but keep
2900       // the address link around that so that existing activations can
2901       // be invalidated.
2902       InstalledCode::set_entryPoint(installed_code, 0);
2903     }
2904   }
2905 }
2906 
2907 void nmethod::invalidate_installed_code(Handle installedCode, TRAPS) {
2908   if (installedCode() == NULL) {
2909     THROW(vmSymbols::java_lang_NullPointerException());
2910   }
2911   jlong nativeMethod = InstalledCode::address(installedCode);
2912   nmethod* nm = (nmethod*)nativeMethod;
2913   if (nm == NULL) {
2914     // Nothing to do
2915     return;
2916   }
2917 
2918   nmethodLocker nml(nm);
2919 #ifdef ASSERT
2920   {
2921     MutexLockerEx pl(Patching_lock, Mutex::_no_safepoint_check_flag);
2922     // This relationship can only be checked safely under a lock
2923     assert(nm == NULL || !nm->is_alive() || nm->jvmci_installed_code() == installedCode(), "sanity check");
2924   }
2925 #endif
2926 
2927   if (nm->is_alive()) {
2928     // The nmethod state machinery maintains the link between the
2929     // HotSpotInstalledCode and nmethod* so as long as the nmethod appears to be
2930     // alive assume there is work to do and deoptimize the nmethod.
2931     nm->mark_for_deoptimization();
2932     VM_Deoptimize op;
2933     VMThread::execute(&op);
2934   }
2935 
2936   MutexLockerEx pl(Patching_lock, Mutex::_no_safepoint_check_flag);
2937   // Check that it's still associated with the same nmethod and break
2938   // the link if it is.
2939   if (InstalledCode::address(installedCode) == nativeMethod) {
2940     InstalledCode::set_address(installedCode, 0);
2941   }
2942 }
2943 
2944 char* nmethod::jvmci_installed_code_name(char* buf, size_t buflen) {
2945   if (!this->is_compiled_by_jvmci()) {
2946     return NULL;
2947   }
2948   oop installedCode = this->jvmci_installed_code();
2949   if (installedCode != NULL) {
2950     oop installedCodeName = NULL;
2951     if (installedCode->is_a(InstalledCode::klass())) {
2952       installedCodeName = InstalledCode::name(installedCode);
2953     }
2954     if (installedCodeName != NULL) {
2955       return java_lang_String::as_utf8_string(installedCodeName, buf, (int)buflen);
2956     } else {
2957       jio_snprintf(buf, buflen, "null");
2958       return buf;
2959     }
2960   }
2961   jio_snprintf(buf, buflen, "noInstalledCode");
2962   return buf;
2963 }
2964 #endif
--- EOF ---