src/share/vm/code/nmethod.cpp

Fri, 29 Jan 2010 09:27:22 -0800

author
kvn
date
Fri, 29 Jan 2010 09:27:22 -0800
changeset 1637
5f24d0319e54
parent 1636
24128c2ffa87
child 1639
18a389214829
permissions
-rw-r--r--

4360113: Evict nmethods when code cache gets full
Summary: Speculatively unload the oldest nmethods when code cache gets full.
Reviewed-by: never, kvn
Contributed-by: eric.caspole@amd.com

     1 /*
     2  * Copyright 1997-2009 Sun Microsystems, Inc.  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 Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
    20  * CA 95054 USA or visit www.sun.com if you need additional information or
    21  * have any questions.
    22  *
    23  */
    25 # include "incls/_precompiled.incl"
    26 # include "incls/_nmethod.cpp.incl"
    28 #ifdef DTRACE_ENABLED
    30 // Only bother with this argument setup if dtrace is available
    32 HS_DTRACE_PROBE_DECL8(hotspot, compiled__method__load,
    33   const char*, int, const char*, int, const char*, int, void*, size_t);
    35 HS_DTRACE_PROBE_DECL6(hotspot, compiled__method__unload,
    36   char*, int, char*, int, char*, int);
    38 #define DTRACE_METHOD_UNLOAD_PROBE(method)                                \
    39   {                                                                       \
    40     methodOop m = (method);                                               \
    41     if (m != NULL) {                                                      \
    42       symbolOop klass_name = m->klass_name();                             \
    43       symbolOop name = m->name();                                         \
    44       symbolOop signature = m->signature();                               \
    45       HS_DTRACE_PROBE6(hotspot, compiled__method__unload,                 \
    46         klass_name->bytes(), klass_name->utf8_length(),                   \
    47         name->bytes(), name->utf8_length(),                               \
    48         signature->bytes(), signature->utf8_length());                    \
    49     }                                                                     \
    50   }
    52 #else //  ndef DTRACE_ENABLED
    54 #define DTRACE_METHOD_UNLOAD_PROBE(method)
    56 #endif
    58 bool nmethod::is_compiled_by_c1() const {
    59   if (compiler() == NULL || method() == NULL)  return false;  // can happen during debug printing
    60   if (is_native_method()) return false;
    61   return compiler()->is_c1();
    62 }
    63 bool nmethod::is_compiled_by_c2() const {
    64   if (compiler() == NULL || method() == NULL)  return false;  // can happen during debug printing
    65   if (is_native_method()) return false;
    66   return compiler()->is_c2();
    67 }
    71 //---------------------------------------------------------------------------------
    72 // NMethod statistics
    73 // They are printed under various flags, including:
    74 //   PrintC1Statistics, PrintOptoStatistics, LogVMOutput, and LogCompilation.
    75 // (In the latter two cases, they like other stats are printed to the log only.)
    77 #ifndef PRODUCT
    78 // These variables are put into one block to reduce relocations
    79 // and make it simpler to print from the debugger.
    80 static
    81 struct nmethod_stats_struct {
    82   int nmethod_count;
    83   int total_size;
    84   int relocation_size;
    85   int code_size;
    86   int stub_size;
    87   int consts_size;
    88   int scopes_data_size;
    89   int scopes_pcs_size;
    90   int dependencies_size;
    91   int handler_table_size;
    92   int nul_chk_table_size;
    93   int oops_size;
    95   void note_nmethod(nmethod* nm) {
    96     nmethod_count += 1;
    97     total_size          += nm->size();
    98     relocation_size     += nm->relocation_size();
    99     code_size           += nm->code_size();
   100     stub_size           += nm->stub_size();
   101     consts_size         += nm->consts_size();
   102     scopes_data_size    += nm->scopes_data_size();
   103     scopes_pcs_size     += nm->scopes_pcs_size();
   104     dependencies_size   += nm->dependencies_size();
   105     handler_table_size  += nm->handler_table_size();
   106     nul_chk_table_size  += nm->nul_chk_table_size();
   107     oops_size += nm->oops_size();
   108   }
   109   void print_nmethod_stats() {
   110     if (nmethod_count == 0)  return;
   111     tty->print_cr("Statistics for %d bytecoded nmethods:", nmethod_count);
   112     if (total_size != 0)          tty->print_cr(" total in heap  = %d", total_size);
   113     if (relocation_size != 0)     tty->print_cr(" relocation     = %d", relocation_size);
   114     if (code_size != 0)           tty->print_cr(" main code      = %d", code_size);
   115     if (stub_size != 0)           tty->print_cr(" stub code      = %d", stub_size);
   116     if (consts_size != 0)         tty->print_cr(" constants      = %d", consts_size);
   117     if (scopes_data_size != 0)    tty->print_cr(" scopes data    = %d", scopes_data_size);
   118     if (scopes_pcs_size != 0)     tty->print_cr(" scopes pcs     = %d", scopes_pcs_size);
   119     if (dependencies_size != 0)   tty->print_cr(" dependencies   = %d", dependencies_size);
   120     if (handler_table_size != 0)  tty->print_cr(" handler table  = %d", handler_table_size);
   121     if (nul_chk_table_size != 0)  tty->print_cr(" nul chk table  = %d", nul_chk_table_size);
   122     if (oops_size != 0)           tty->print_cr(" oops           = %d", oops_size);
   123   }
   125   int native_nmethod_count;
   126   int native_total_size;
   127   int native_relocation_size;
   128   int native_code_size;
   129   int native_oops_size;
   130   void note_native_nmethod(nmethod* nm) {
   131     native_nmethod_count += 1;
   132     native_total_size       += nm->size();
   133     native_relocation_size  += nm->relocation_size();
   134     native_code_size        += nm->code_size();
   135     native_oops_size        += nm->oops_size();
   136   }
   137   void print_native_nmethod_stats() {
   138     if (native_nmethod_count == 0)  return;
   139     tty->print_cr("Statistics for %d native nmethods:", native_nmethod_count);
   140     if (native_total_size != 0)       tty->print_cr(" N. total size  = %d", native_total_size);
   141     if (native_relocation_size != 0)  tty->print_cr(" N. relocation  = %d", native_relocation_size);
   142     if (native_code_size != 0)        tty->print_cr(" N. main code   = %d", native_code_size);
   143     if (native_oops_size != 0)        tty->print_cr(" N. oops        = %d", native_oops_size);
   144   }
   146   int pc_desc_resets;   // number of resets (= number of caches)
   147   int pc_desc_queries;  // queries to nmethod::find_pc_desc
   148   int pc_desc_approx;   // number of those which have approximate true
   149   int pc_desc_repeats;  // number of _last_pc_desc hits
   150   int pc_desc_hits;     // number of LRU cache hits
   151   int pc_desc_tests;    // total number of PcDesc examinations
   152   int pc_desc_searches; // total number of quasi-binary search steps
   153   int pc_desc_adds;     // number of LUR cache insertions
   155   void print_pc_stats() {
   156     tty->print_cr("PcDesc Statistics:  %d queries, %.2f comparisons per query",
   157                   pc_desc_queries,
   158                   (double)(pc_desc_tests + pc_desc_searches)
   159                   / pc_desc_queries);
   160     tty->print_cr("  caches=%d queries=%d/%d, hits=%d+%d, tests=%d+%d, adds=%d",
   161                   pc_desc_resets,
   162                   pc_desc_queries, pc_desc_approx,
   163                   pc_desc_repeats, pc_desc_hits,
   164                   pc_desc_tests, pc_desc_searches, pc_desc_adds);
   165   }
   166 } nmethod_stats;
   167 #endif //PRODUCT
   169 //---------------------------------------------------------------------------------
   172 // The _unwind_handler is a special marker address, which says that
   173 // for given exception oop and address, the frame should be removed
   174 // as the tuple cannot be caught in the nmethod
   175 address ExceptionCache::_unwind_handler = (address) -1;
   178 ExceptionCache::ExceptionCache(Handle exception, address pc, address handler) {
   179   assert(pc != NULL, "Must be non null");
   180   assert(exception.not_null(), "Must be non null");
   181   assert(handler != NULL, "Must be non null");
   183   _count = 0;
   184   _exception_type = exception->klass();
   185   _next = NULL;
   187   add_address_and_handler(pc,handler);
   188 }
   191 address ExceptionCache::match(Handle exception, address pc) {
   192   assert(pc != NULL,"Must be non null");
   193   assert(exception.not_null(),"Must be non null");
   194   if (exception->klass() == exception_type()) {
   195     return (test_address(pc));
   196   }
   198   return NULL;
   199 }
   202 bool ExceptionCache::match_exception_with_space(Handle exception) {
   203   assert(exception.not_null(),"Must be non null");
   204   if (exception->klass() == exception_type() && count() < cache_size) {
   205     return true;
   206   }
   207   return false;
   208 }
   211 address ExceptionCache::test_address(address addr) {
   212   for (int i=0; i<count(); i++) {
   213     if (pc_at(i) == addr) {
   214       return handler_at(i);
   215     }
   216   }
   217   return NULL;
   218 }
   221 bool ExceptionCache::add_address_and_handler(address addr, address handler) {
   222   if (test_address(addr) == handler) return true;
   223   if (count() < cache_size) {
   224     set_pc_at(count(),addr);
   225     set_handler_at(count(), handler);
   226     increment_count();
   227     return true;
   228   }
   229   return false;
   230 }
   233 // private method for handling exception cache
   234 // These methods are private, and used to manipulate the exception cache
   235 // directly.
   236 ExceptionCache* nmethod::exception_cache_entry_for_exception(Handle exception) {
   237   ExceptionCache* ec = exception_cache();
   238   while (ec != NULL) {
   239     if (ec->match_exception_with_space(exception)) {
   240       return ec;
   241     }
   242     ec = ec->next();
   243   }
   244   return NULL;
   245 }
   248 //-----------------------------------------------------------------------------
   251 // Helper used by both find_pc_desc methods.
   252 static inline bool match_desc(PcDesc* pc, int pc_offset, bool approximate) {
   253   NOT_PRODUCT(++nmethod_stats.pc_desc_tests);
   254   if (!approximate)
   255     return pc->pc_offset() == pc_offset;
   256   else
   257     return (pc-1)->pc_offset() < pc_offset && pc_offset <= pc->pc_offset();
   258 }
   260 void PcDescCache::reset_to(PcDesc* initial_pc_desc) {
   261   if (initial_pc_desc == NULL) {
   262     _last_pc_desc = NULL;  // native method
   263     return;
   264   }
   265   NOT_PRODUCT(++nmethod_stats.pc_desc_resets);
   266   // reset the cache by filling it with benign (non-null) values
   267   assert(initial_pc_desc->pc_offset() < 0, "must be sentinel");
   268   _last_pc_desc = initial_pc_desc + 1;  // first valid one is after sentinel
   269   for (int i = 0; i < cache_size; i++)
   270     _pc_descs[i] = initial_pc_desc;
   271 }
   273 PcDesc* PcDescCache::find_pc_desc(int pc_offset, bool approximate) {
   274   NOT_PRODUCT(++nmethod_stats.pc_desc_queries);
   275   NOT_PRODUCT(if (approximate)  ++nmethod_stats.pc_desc_approx);
   277   // In order to prevent race conditions do not load cache elements
   278   // repeatedly, but use a local copy:
   279   PcDesc* res;
   281   // Step one:  Check the most recently returned value.
   282   res = _last_pc_desc;
   283   if (res == NULL)  return NULL;  // native method; no PcDescs at all
   284   if (match_desc(res, pc_offset, approximate)) {
   285     NOT_PRODUCT(++nmethod_stats.pc_desc_repeats);
   286     return res;
   287   }
   289   // Step two:  Check the LRU cache.
   290   for (int i = 0; i < cache_size; i++) {
   291     res = _pc_descs[i];
   292     if (res->pc_offset() < 0)  break;  // optimization: skip empty cache
   293     if (match_desc(res, pc_offset, approximate)) {
   294       NOT_PRODUCT(++nmethod_stats.pc_desc_hits);
   295       _last_pc_desc = res;  // record this cache hit in case of repeat
   296       return res;
   297     }
   298   }
   300   // Report failure.
   301   return NULL;
   302 }
   304 void PcDescCache::add_pc_desc(PcDesc* pc_desc) {
   305   NOT_PRODUCT(++nmethod_stats.pc_desc_adds);
   306   // Update the LRU cache by shifting pc_desc forward:
   307   for (int i = 0; i < cache_size; i++)  {
   308     PcDesc* next = _pc_descs[i];
   309     _pc_descs[i] = pc_desc;
   310     pc_desc = next;
   311   }
   312   // Note:  Do not update _last_pc_desc.  It fronts for the LRU cache.
   313 }
   315 // adjust pcs_size so that it is a multiple of both oopSize and
   316 // sizeof(PcDesc) (assumes that if sizeof(PcDesc) is not a multiple
   317 // of oopSize, then 2*sizeof(PcDesc) is)
   318 static int  adjust_pcs_size(int pcs_size) {
   319   int nsize = round_to(pcs_size,   oopSize);
   320   if ((nsize % sizeof(PcDesc)) != 0) {
   321     nsize = pcs_size + sizeof(PcDesc);
   322   }
   323   assert((nsize %  oopSize) == 0, "correct alignment");
   324   return nsize;
   325 }
   327 //-----------------------------------------------------------------------------
   330 void nmethod::add_exception_cache_entry(ExceptionCache* new_entry) {
   331   assert(ExceptionCache_lock->owned_by_self(),"Must hold the ExceptionCache_lock");
   332   assert(new_entry != NULL,"Must be non null");
   333   assert(new_entry->next() == NULL, "Must be null");
   335   if (exception_cache() != NULL) {
   336     new_entry->set_next(exception_cache());
   337   }
   338   set_exception_cache(new_entry);
   339 }
   341 void nmethod::remove_from_exception_cache(ExceptionCache* ec) {
   342   ExceptionCache* prev = NULL;
   343   ExceptionCache* curr = exception_cache();
   344   assert(curr != NULL, "nothing to remove");
   345   // find the previous and next entry of ec
   346   while (curr != ec) {
   347     prev = curr;
   348     curr = curr->next();
   349     assert(curr != NULL, "ExceptionCache not found");
   350   }
   351   // now: curr == ec
   352   ExceptionCache* next = curr->next();
   353   if (prev == NULL) {
   354     set_exception_cache(next);
   355   } else {
   356     prev->set_next(next);
   357   }
   358   delete curr;
   359 }
   362 // public method for accessing the exception cache
   363 // These are the public access methods.
   364 address nmethod::handler_for_exception_and_pc(Handle exception, address pc) {
   365   // We never grab a lock to read the exception cache, so we may
   366   // have false negatives. This is okay, as it can only happen during
   367   // the first few exception lookups for a given nmethod.
   368   ExceptionCache* ec = exception_cache();
   369   while (ec != NULL) {
   370     address ret_val;
   371     if ((ret_val = ec->match(exception,pc)) != NULL) {
   372       return ret_val;
   373     }
   374     ec = ec->next();
   375   }
   376   return NULL;
   377 }
   380 void nmethod::add_handler_for_exception_and_pc(Handle exception, address pc, address handler) {
   381   // There are potential race conditions during exception cache updates, so we
   382   // must own the ExceptionCache_lock before doing ANY modifications. Because
   383   // we don't lock during reads, it is possible to have several threads attempt
   384   // to update the cache with the same data. We need to check for already inserted
   385   // copies of the current data before adding it.
   387   MutexLocker ml(ExceptionCache_lock);
   388   ExceptionCache* target_entry = exception_cache_entry_for_exception(exception);
   390   if (target_entry == NULL || !target_entry->add_address_and_handler(pc,handler)) {
   391     target_entry = new ExceptionCache(exception,pc,handler);
   392     add_exception_cache_entry(target_entry);
   393   }
   394 }
   397 //-------------end of code for ExceptionCache--------------
   400 void nmFlags::clear() {
   401   assert(sizeof(nmFlags) == sizeof(int), "using more than one word for nmFlags");
   402   *(jint*)this = 0;
   403 }
   405 int nmethod::total_size() const {
   406   return
   407     code_size()          +
   408     stub_size()          +
   409     consts_size()        +
   410     scopes_data_size()   +
   411     scopes_pcs_size()    +
   412     handler_table_size() +
   413     nul_chk_table_size();
   414 }
   416 const char* nmethod::compile_kind() const {
   417   if (is_osr_method())     return "osr";
   418   if (method() != NULL && is_native_method())  return "c2n";
   419   return NULL;
   420 }
   422 // %%% This variable is no longer used?
   423 int nmethod::_zombie_instruction_size = NativeJump::instruction_size;
   426 nmethod* nmethod::new_native_nmethod(methodHandle method,
   427   CodeBuffer *code_buffer,
   428   int vep_offset,
   429   int frame_complete,
   430   int frame_size,
   431   ByteSize basic_lock_owner_sp_offset,
   432   ByteSize basic_lock_sp_offset,
   433   OopMapSet* oop_maps) {
   434   // create nmethod
   435   nmethod* nm = NULL;
   436   {
   437     MutexLockerEx mu(CodeCache_lock, Mutex::_no_safepoint_check_flag);
   438     int native_nmethod_size = allocation_size(code_buffer, sizeof(nmethod));
   439     CodeOffsets offsets;
   440     offsets.set_value(CodeOffsets::Verified_Entry, vep_offset);
   441     offsets.set_value(CodeOffsets::Frame_Complete, frame_complete);
   442     nm = new (native_nmethod_size)
   443       nmethod(method(), native_nmethod_size, &offsets,
   444               code_buffer, frame_size,
   445               basic_lock_owner_sp_offset, basic_lock_sp_offset,
   446               oop_maps);
   447     NOT_PRODUCT(if (nm != NULL)  nmethod_stats.note_native_nmethod(nm));
   448     if (PrintAssembly && nm != NULL)
   449       Disassembler::decode(nm);
   450   }
   451   // verify nmethod
   452   debug_only(if (nm) nm->verify();) // might block
   454   if (nm != NULL) {
   455     nm->log_new_nmethod();
   456   }
   458   return nm;
   459 }
   461 #ifdef HAVE_DTRACE_H
   462 nmethod* nmethod::new_dtrace_nmethod(methodHandle method,
   463                                      CodeBuffer *code_buffer,
   464                                      int vep_offset,
   465                                      int trap_offset,
   466                                      int frame_complete,
   467                                      int frame_size) {
   468   // create nmethod
   469   nmethod* nm = NULL;
   470   {
   471     MutexLockerEx mu(CodeCache_lock, Mutex::_no_safepoint_check_flag);
   472     int nmethod_size = allocation_size(code_buffer, sizeof(nmethod));
   473     CodeOffsets offsets;
   474     offsets.set_value(CodeOffsets::Verified_Entry, vep_offset);
   475     offsets.set_value(CodeOffsets::Dtrace_trap, trap_offset);
   476     offsets.set_value(CodeOffsets::Frame_Complete, frame_complete);
   478     nm = new (nmethod_size) nmethod(method(), nmethod_size, &offsets, code_buffer, frame_size);
   480     NOT_PRODUCT(if (nm != NULL)  nmethod_stats.note_nmethod(nm));
   481     if (PrintAssembly && nm != NULL)
   482       Disassembler::decode(nm);
   483   }
   484   // verify nmethod
   485   debug_only(if (nm) nm->verify();) // might block
   487   if (nm != NULL) {
   488     nm->log_new_nmethod();
   489   }
   491   return nm;
   492 }
   494 #endif // def HAVE_DTRACE_H
   496 nmethod* nmethod::new_nmethod(methodHandle method,
   497   int compile_id,
   498   int entry_bci,
   499   CodeOffsets* offsets,
   500   int orig_pc_offset,
   501   DebugInformationRecorder* debug_info,
   502   Dependencies* dependencies,
   503   CodeBuffer* code_buffer, int frame_size,
   504   OopMapSet* oop_maps,
   505   ExceptionHandlerTable* handler_table,
   506   ImplicitExceptionTable* nul_chk_table,
   507   AbstractCompiler* compiler,
   508   int comp_level
   509 )
   510 {
   511   assert(debug_info->oop_recorder() == code_buffer->oop_recorder(), "shared OR");
   512   // create nmethod
   513   nmethod* nm = NULL;
   514   { MutexLockerEx mu(CodeCache_lock, Mutex::_no_safepoint_check_flag);
   515     int nmethod_size =
   516       allocation_size(code_buffer, sizeof(nmethod))
   517       + adjust_pcs_size(debug_info->pcs_size())
   518       + round_to(dependencies->size_in_bytes() , oopSize)
   519       + round_to(handler_table->size_in_bytes(), oopSize)
   520       + round_to(nul_chk_table->size_in_bytes(), oopSize)
   521       + round_to(debug_info->data_size()       , oopSize);
   522     nm = new (nmethod_size)
   523       nmethod(method(), nmethod_size, compile_id, entry_bci, offsets,
   524               orig_pc_offset, debug_info, dependencies, code_buffer, frame_size,
   525               oop_maps,
   526               handler_table,
   527               nul_chk_table,
   528               compiler,
   529               comp_level);
   530     if (nm != NULL) {
   531       // To make dependency checking during class loading fast, record
   532       // the nmethod dependencies in the classes it is dependent on.
   533       // This allows the dependency checking code to simply walk the
   534       // class hierarchy above the loaded class, checking only nmethods
   535       // which are dependent on those classes.  The slow way is to
   536       // check every nmethod for dependencies which makes it linear in
   537       // the number of methods compiled.  For applications with a lot
   538       // classes the slow way is too slow.
   539       for (Dependencies::DepStream deps(nm); deps.next(); ) {
   540         klassOop klass = deps.context_type();
   541         if (klass == NULL)  continue;  // ignore things like evol_method
   543         // record this nmethod as dependent on this klass
   544         instanceKlass::cast(klass)->add_dependent_nmethod(nm);
   545       }
   546     }
   547     NOT_PRODUCT(if (nm != NULL)  nmethod_stats.note_nmethod(nm));
   548     if (PrintAssembly && nm != NULL)
   549       Disassembler::decode(nm);
   550   }
   552   // verify nmethod
   553   debug_only(if (nm) nm->verify();) // might block
   555   if (nm != NULL) {
   556     nm->log_new_nmethod();
   557   }
   559   // done
   560   return nm;
   561 }
   564 // For native wrappers
   565 nmethod::nmethod(
   566   methodOop method,
   567   int nmethod_size,
   568   CodeOffsets* offsets,
   569   CodeBuffer* code_buffer,
   570   int frame_size,
   571   ByteSize basic_lock_owner_sp_offset,
   572   ByteSize basic_lock_sp_offset,
   573   OopMapSet* oop_maps )
   574   : CodeBlob("native nmethod", code_buffer, sizeof(nmethod),
   575              nmethod_size, offsets->value(CodeOffsets::Frame_Complete), frame_size, oop_maps),
   576   _compiled_synchronized_native_basic_lock_owner_sp_offset(basic_lock_owner_sp_offset),
   577   _compiled_synchronized_native_basic_lock_sp_offset(basic_lock_sp_offset)
   578 {
   579   {
   580     debug_only(No_Safepoint_Verifier nsv;)
   581     assert_locked_or_safepoint(CodeCache_lock);
   583     NOT_PRODUCT(_has_debug_info = false);
   584     _oops_do_mark_link       = NULL;
   585     _method                  = method;
   586     _entry_bci               = InvocationEntryBci;
   587     _osr_link                = NULL;
   588     _scavenge_root_link      = NULL;
   589     _scavenge_root_state     = 0;
   590     _saved_nmethod_link      = NULL;
   591     _compiler                = NULL;
   592     // We have no exception handler or deopt handler make the
   593     // values something that will never match a pc like the nmethod vtable entry
   594     _exception_offset        = 0;
   595     _deoptimize_offset       = 0;
   596     _orig_pc_offset          = 0;
   597 #ifdef HAVE_DTRACE_H
   598     _trap_offset             = 0;
   599 #endif // def HAVE_DTRACE_H
   600     _stub_offset             = data_offset();
   601     _consts_offset           = data_offset();
   602     _scopes_data_offset      = data_offset();
   603     _scopes_pcs_offset       = _scopes_data_offset;
   604     _dependencies_offset     = _scopes_pcs_offset;
   605     _handler_table_offset    = _dependencies_offset;
   606     _nul_chk_table_offset    = _handler_table_offset;
   607     _nmethod_end_offset      = _nul_chk_table_offset;
   608     _compile_id              = 0;  // default
   609     _comp_level              = CompLevel_none;
   610     _entry_point             = instructions_begin();
   611     _verified_entry_point    = instructions_begin() + offsets->value(CodeOffsets::Verified_Entry);
   612     _osr_entry_point         = NULL;
   613     _exception_cache         = NULL;
   614     _pc_desc_cache.reset_to(NULL);
   616     flags.clear();
   617     flags.state              = alive;
   618     _markedForDeoptimization = 0;
   620     _lock_count = 0;
   621     _stack_traversal_mark    = 0;
   623     code_buffer->copy_oops_to(this);
   624     debug_only(verify_scavenge_root_oops());
   625     CodeCache::commit(this);
   626     VTune::create_nmethod(this);
   627   }
   629   if (PrintNativeNMethods || PrintDebugInfo || PrintRelocations || PrintDependencies) {
   630     ttyLocker ttyl;  // keep the following output all in one block
   631     // This output goes directly to the tty, not the compiler log.
   632     // To enable tools to match it up with the compilation activity,
   633     // be sure to tag this tty output with the compile ID.
   634     if (xtty != NULL) {
   635       xtty->begin_head("print_native_nmethod");
   636       xtty->method(_method);
   637       xtty->stamp();
   638       xtty->end_head(" address='" INTPTR_FORMAT "'", (intptr_t) this);
   639     }
   640     // print the header part first
   641     print();
   642     // then print the requested information
   643     if (PrintNativeNMethods) {
   644       print_code();
   645       oop_maps->print();
   646     }
   647     if (PrintRelocations) {
   648       print_relocations();
   649     }
   650     if (xtty != NULL) {
   651       xtty->tail("print_native_nmethod");
   652     }
   653   }
   654   Events::log("Create nmethod " INTPTR_FORMAT, this);
   655 }
   657 // For dtrace wrappers
   658 #ifdef HAVE_DTRACE_H
   659 nmethod::nmethod(
   660   methodOop method,
   661   int nmethod_size,
   662   CodeOffsets* offsets,
   663   CodeBuffer* code_buffer,
   664   int frame_size)
   665   : CodeBlob("dtrace nmethod", code_buffer, sizeof(nmethod),
   666              nmethod_size, offsets->value(CodeOffsets::Frame_Complete), frame_size, NULL),
   667   _compiled_synchronized_native_basic_lock_owner_sp_offset(in_ByteSize(-1)),
   668   _compiled_synchronized_native_basic_lock_sp_offset(in_ByteSize(-1))
   669 {
   670   {
   671     debug_only(No_Safepoint_Verifier nsv;)
   672     assert_locked_or_safepoint(CodeCache_lock);
   674     NOT_PRODUCT(_has_debug_info = false);
   675     _oops_do_mark_link       = NULL;
   676     _method                  = method;
   677     _entry_bci               = InvocationEntryBci;
   678     _osr_link                = NULL;
   679     _scavenge_root_link      = NULL;
   680     _scavenge_root_state     = 0;
   681     _compiler                = NULL;
   682     // We have no exception handler or deopt handler make the
   683     // values something that will never match a pc like the nmethod vtable entry
   684     _exception_offset        = 0;
   685     _deoptimize_offset       = 0;
   686     _trap_offset             = offsets->value(CodeOffsets::Dtrace_trap);
   687     _orig_pc_offset          = 0;
   688     _stub_offset             = data_offset();
   689     _consts_offset           = data_offset();
   690     _scopes_data_offset      = data_offset();
   691     _scopes_pcs_offset       = _scopes_data_offset;
   692     _dependencies_offset     = _scopes_pcs_offset;
   693     _handler_table_offset    = _dependencies_offset;
   694     _nul_chk_table_offset    = _handler_table_offset;
   695     _nmethod_end_offset      = _nul_chk_table_offset;
   696     _compile_id              = 0;  // default
   697     _comp_level              = CompLevel_none;
   698     _entry_point             = instructions_begin();
   699     _verified_entry_point    = instructions_begin() + offsets->value(CodeOffsets::Verified_Entry);
   700     _osr_entry_point         = NULL;
   701     _exception_cache         = NULL;
   702     _pc_desc_cache.reset_to(NULL);
   704     flags.clear();
   705     flags.state              = alive;
   706     _markedForDeoptimization = 0;
   708     _lock_count = 0;
   709     _stack_traversal_mark    = 0;
   711     code_buffer->copy_oops_to(this);
   712     debug_only(verify_scavenge_root_oops());
   713     CodeCache::commit(this);
   714     VTune::create_nmethod(this);
   715   }
   717   if (PrintNMethods || PrintDebugInfo || PrintRelocations || PrintDependencies) {
   718     ttyLocker ttyl;  // keep the following output all in one block
   719     // This output goes directly to the tty, not the compiler log.
   720     // To enable tools to match it up with the compilation activity,
   721     // be sure to tag this tty output with the compile ID.
   722     if (xtty != NULL) {
   723       xtty->begin_head("print_dtrace_nmethod");
   724       xtty->method(_method);
   725       xtty->stamp();
   726       xtty->end_head(" address='" INTPTR_FORMAT "'", (intptr_t) this);
   727     }
   728     // print the header part first
   729     print();
   730     // then print the requested information
   731     if (PrintNMethods) {
   732       print_code();
   733     }
   734     if (PrintRelocations) {
   735       print_relocations();
   736     }
   737     if (xtty != NULL) {
   738       xtty->tail("print_dtrace_nmethod");
   739     }
   740   }
   741   Events::log("Create nmethod " INTPTR_FORMAT, this);
   742 }
   743 #endif // def HAVE_DTRACE_H
   745 void* nmethod::operator new(size_t size, int nmethod_size) {
   746   // Always leave some room in the CodeCache for I2C/C2I adapters
   747   if (CodeCache::unallocated_capacity() < CodeCacheMinimumFreeSpace) return NULL;
   748   return CodeCache::allocate(nmethod_size);
   749 }
   752 nmethod::nmethod(
   753   methodOop method,
   754   int nmethod_size,
   755   int compile_id,
   756   int entry_bci,
   757   CodeOffsets* offsets,
   758   int orig_pc_offset,
   759   DebugInformationRecorder* debug_info,
   760   Dependencies* dependencies,
   761   CodeBuffer *code_buffer,
   762   int frame_size,
   763   OopMapSet* oop_maps,
   764   ExceptionHandlerTable* handler_table,
   765   ImplicitExceptionTable* nul_chk_table,
   766   AbstractCompiler* compiler,
   767   int comp_level
   768   )
   769   : CodeBlob("nmethod", code_buffer, sizeof(nmethod),
   770              nmethod_size, offsets->value(CodeOffsets::Frame_Complete), frame_size, oop_maps),
   771   _compiled_synchronized_native_basic_lock_owner_sp_offset(in_ByteSize(-1)),
   772   _compiled_synchronized_native_basic_lock_sp_offset(in_ByteSize(-1))
   773 {
   774   assert(debug_info->oop_recorder() == code_buffer->oop_recorder(), "shared OR");
   775   {
   776     debug_only(No_Safepoint_Verifier nsv;)
   777     assert_locked_or_safepoint(CodeCache_lock);
   779     NOT_PRODUCT(_has_debug_info = false);
   780     _oops_do_mark_link       = NULL;
   781     _method                  = method;
   782     _compile_id              = compile_id;
   783     _comp_level              = comp_level;
   784     _entry_bci               = entry_bci;
   785     _osr_link                = NULL;
   786     _scavenge_root_link      = NULL;
   787     _scavenge_root_state     = 0;
   788     _compiler                = compiler;
   789     _orig_pc_offset          = orig_pc_offset;
   790 #ifdef HAVE_DTRACE_H
   791     _trap_offset             = 0;
   792 #endif // def HAVE_DTRACE_H
   793     _stub_offset             = instructions_offset() + code_buffer->total_offset_of(code_buffer->stubs()->start());
   795     // Exception handler and deopt handler are in the stub section
   796     _exception_offset        = _stub_offset + offsets->value(CodeOffsets::Exceptions);
   797     _deoptimize_offset       = _stub_offset + offsets->value(CodeOffsets::Deopt);
   798     _consts_offset           = instructions_offset() + code_buffer->total_offset_of(code_buffer->consts()->start());
   799     _scopes_data_offset      = data_offset();
   800     _scopes_pcs_offset       = _scopes_data_offset   + round_to(debug_info->data_size         (), oopSize);
   801     _dependencies_offset     = _scopes_pcs_offset    + adjust_pcs_size(debug_info->pcs_size());
   802     _handler_table_offset    = _dependencies_offset  + round_to(dependencies->size_in_bytes (), oopSize);
   803     _nul_chk_table_offset    = _handler_table_offset + round_to(handler_table->size_in_bytes(), oopSize);
   804     _nmethod_end_offset      = _nul_chk_table_offset + round_to(nul_chk_table->size_in_bytes(), oopSize);
   806     _entry_point             = instructions_begin();
   807     _verified_entry_point    = instructions_begin() + offsets->value(CodeOffsets::Verified_Entry);
   808     _osr_entry_point         = instructions_begin() + offsets->value(CodeOffsets::OSR_Entry);
   809     _exception_cache         = NULL;
   810     _pc_desc_cache.reset_to(scopes_pcs_begin());
   812     flags.clear();
   813     flags.state              = alive;
   814     _markedForDeoptimization = 0;
   816     _unload_reported         = false;           // jvmti state
   818     _lock_count = 0;
   819     _stack_traversal_mark    = 0;
   821     // Copy contents of ScopeDescRecorder to nmethod
   822     code_buffer->copy_oops_to(this);
   823     debug_info->copy_to(this);
   824     dependencies->copy_to(this);
   825     if (ScavengeRootsInCode && detect_scavenge_root_oops()) {
   826       CodeCache::add_scavenge_root_nmethod(this);
   827     }
   828     debug_only(verify_scavenge_root_oops());
   830     CodeCache::commit(this);
   832     VTune::create_nmethod(this);
   834     // Copy contents of ExceptionHandlerTable to nmethod
   835     handler_table->copy_to(this);
   836     nul_chk_table->copy_to(this);
   838     // we use the information of entry points to find out if a method is
   839     // static or non static
   840     assert(compiler->is_c2() ||
   841            _method->is_static() == (entry_point() == _verified_entry_point),
   842            " entry points must be same for static methods and vice versa");
   843   }
   845   bool printnmethods = PrintNMethods
   846     || CompilerOracle::should_print(_method)
   847     || CompilerOracle::has_option_string(_method, "PrintNMethods");
   848   if (printnmethods || PrintDebugInfo || PrintRelocations || PrintDependencies || PrintExceptionHandlers) {
   849     print_nmethod(printnmethods);
   850   }
   852   // Note: Do not verify in here as the CodeCache_lock is
   853   //       taken which would conflict with the CompiledIC_lock
   854   //       which taken during the verification of call sites.
   855   //       (was bug - gri 10/25/99)
   857   Events::log("Create nmethod " INTPTR_FORMAT, this);
   858 }
   861 // Print a short set of xml attributes to identify this nmethod.  The
   862 // output should be embedded in some other element.
   863 void nmethod::log_identity(xmlStream* log) const {
   864   log->print(" compile_id='%d'", compile_id());
   865   const char* nm_kind = compile_kind();
   866   if (nm_kind != NULL)  log->print(" compile_kind='%s'", nm_kind);
   867   if (compiler() != NULL) {
   868     log->print(" compiler='%s'", compiler()->name());
   869   }
   870 #ifdef TIERED
   871   log->print(" level='%d'", comp_level());
   872 #endif // TIERED
   873 }
   876 #define LOG_OFFSET(log, name)                    \
   877   if ((intptr_t)name##_end() - (intptr_t)name##_begin()) \
   878     log->print(" " XSTR(name) "_offset='%d'"    , \
   879                (intptr_t)name##_begin() - (intptr_t)this)
   882 void nmethod::log_new_nmethod() const {
   883   if (LogCompilation && xtty != NULL) {
   884     ttyLocker ttyl;
   885     HandleMark hm;
   886     xtty->begin_elem("nmethod");
   887     log_identity(xtty);
   888     xtty->print(" entry='" INTPTR_FORMAT "' size='%d'",
   889                 instructions_begin(), size());
   890     xtty->print(" address='" INTPTR_FORMAT "'", (intptr_t) this);
   892     LOG_OFFSET(xtty, relocation);
   893     LOG_OFFSET(xtty, code);
   894     LOG_OFFSET(xtty, stub);
   895     LOG_OFFSET(xtty, consts);
   896     LOG_OFFSET(xtty, scopes_data);
   897     LOG_OFFSET(xtty, scopes_pcs);
   898     LOG_OFFSET(xtty, dependencies);
   899     LOG_OFFSET(xtty, handler_table);
   900     LOG_OFFSET(xtty, nul_chk_table);
   901     LOG_OFFSET(xtty, oops);
   903     xtty->method(method());
   904     xtty->stamp();
   905     xtty->end_elem();
   906   }
   907 }
   909 #undef LOG_OFFSET
   912 // Print out more verbose output usually for a newly created nmethod.
   913 void nmethod::print_on(outputStream* st, const char* title) const {
   914   if (st != NULL) {
   915     ttyLocker ttyl;
   916     // Print a little tag line that looks like +PrintCompilation output:
   917     int tlen = (int) strlen(title);
   918     bool do_nl = false;
   919     if (tlen > 0 && title[tlen-1] == '\n') { tlen--; do_nl = true; }
   920     st->print("%3d%c  %.*s",
   921               compile_id(),
   922               is_osr_method() ? '%' :
   923               method() != NULL &&
   924               is_native_method() ? 'n' : ' ',
   925               tlen, title);
   926 #ifdef TIERED
   927     st->print(" (%d) ", comp_level());
   928 #endif // TIERED
   929     if (WizardMode) st->print(" (" INTPTR_FORMAT ")", this);
   930     if (Universe::heap()->is_gc_active() && method() != NULL) {
   931       st->print("(method)");
   932     } else if (method() != NULL) {
   933         method()->print_short_name(st);
   934       if (is_osr_method())
   935         st->print(" @ %d", osr_entry_bci());
   936       if (method()->code_size() > 0)
   937         st->print(" (%d bytes)", method()->code_size());
   938     }
   940     if (do_nl)  st->cr();
   941   }
   942 }
   945 void nmethod::print_nmethod(bool printmethod) {
   946   ttyLocker ttyl;  // keep the following output all in one block
   947   if (xtty != NULL) {
   948     xtty->begin_head("print_nmethod");
   949     xtty->stamp();
   950     xtty->end_head();
   951   }
   952   // print the header part first
   953   print();
   954   // then print the requested information
   955   if (printmethod) {
   956     print_code();
   957     print_pcs();
   958     oop_maps()->print();
   959   }
   960   if (PrintDebugInfo) {
   961     print_scopes();
   962   }
   963   if (PrintRelocations) {
   964     print_relocations();
   965   }
   966   if (PrintDependencies) {
   967     print_dependencies();
   968   }
   969   if (PrintExceptionHandlers) {
   970     print_handler_table();
   971     print_nul_chk_table();
   972   }
   973   if (xtty != NULL) {
   974     xtty->tail("print_nmethod");
   975   }
   976 }
   979 void nmethod::set_version(int v) {
   980   flags.version = v;
   981 }
   984 ScopeDesc* nmethod::scope_desc_at(address pc) {
   985   PcDesc* pd = pc_desc_at(pc);
   986   guarantee(pd != NULL, "scope must be present");
   987   return new ScopeDesc(this, pd->scope_decode_offset(),
   988                        pd->obj_decode_offset(), pd->should_reexecute());
   989 }
   992 void nmethod::clear_inline_caches() {
   993   assert(SafepointSynchronize::is_at_safepoint(), "cleaning of IC's only allowed at safepoint");
   994   if (is_zombie()) {
   995     return;
   996   }
   998   RelocIterator iter(this);
   999   while (iter.next()) {
  1000     iter.reloc()->clear_inline_cache();
  1005 void nmethod::cleanup_inline_caches() {
  1007   assert(SafepointSynchronize::is_at_safepoint() &&
  1008         !CompiledIC_lock->is_locked() &&
  1009         !Patching_lock->is_locked(), "no threads must be updating the inline caches by them selfs");
  1011   // If the method is not entrant or zombie then a JMP is plastered over the
  1012   // first few bytes.  If an oop in the old code was there, that oop
  1013   // should not get GC'd.  Skip the first few bytes of oops on
  1014   // not-entrant methods.
  1015   address low_boundary = verified_entry_point();
  1016   if (!is_in_use()) {
  1017     low_boundary += NativeJump::instruction_size;
  1018     // %%% Note:  On SPARC we patch only a 4-byte trap, not a full NativeJump.
  1019     // This means that the low_boundary is going to be a little too high.
  1020     // This shouldn't matter, since oops of non-entrant methods are never used.
  1021     // In fact, why are we bothering to look at oops in a non-entrant method??
  1024   // Find all calls in an nmethod, and clear the ones that points to zombie methods
  1025   ResourceMark rm;
  1026   RelocIterator iter(this, low_boundary);
  1027   while(iter.next()) {
  1028     switch(iter.type()) {
  1029       case relocInfo::virtual_call_type:
  1030       case relocInfo::opt_virtual_call_type: {
  1031         CompiledIC *ic = CompiledIC_at(iter.reloc());
  1032         // Ok, to lookup references to zombies here
  1033         CodeBlob *cb = CodeCache::find_blob_unsafe(ic->ic_destination());
  1034         if( cb != NULL && cb->is_nmethod() ) {
  1035           nmethod* nm = (nmethod*)cb;
  1036           // Clean inline caches pointing to both zombie and not_entrant methods
  1037           if (!nm->is_in_use() || (nm->method()->code() != nm)) ic->set_to_clean();
  1039         break;
  1041       case relocInfo::static_call_type: {
  1042         CompiledStaticCall *csc = compiledStaticCall_at(iter.reloc());
  1043         CodeBlob *cb = CodeCache::find_blob_unsafe(csc->destination());
  1044         if( cb != NULL && cb->is_nmethod() ) {
  1045           nmethod* nm = (nmethod*)cb;
  1046           // Clean inline caches pointing to both zombie and not_entrant methods
  1047           if (!nm->is_in_use() || (nm->method()->code() != nm)) csc->set_to_clean();
  1049         break;
  1055 // This is a private interface with the sweeper.
  1056 void nmethod::mark_as_seen_on_stack() {
  1057   assert(is_not_entrant(), "must be a non-entrant method");
  1058   set_stack_traversal_mark(NMethodSweeper::traversal_count());
  1061 // Tell if a non-entrant method can be converted to a zombie (i.e., there is no activations on the stack)
  1062 bool nmethod::can_not_entrant_be_converted() {
  1063   assert(is_not_entrant(), "must be a non-entrant method");
  1064   assert(SafepointSynchronize::is_at_safepoint(), "must be called during a safepoint");
  1066   // Since the nmethod sweeper only does partial sweep the sweeper's traversal
  1067   // count can be greater than the stack traversal count before it hits the
  1068   // nmethod for the second time.
  1069   return stack_traversal_mark()+1 < NMethodSweeper::traversal_count();
  1072 void nmethod::inc_decompile_count() {
  1073   // Could be gated by ProfileTraps, but do not bother...
  1074   methodOop m = method();
  1075   if (m == NULL)  return;
  1076   methodDataOop mdo = m->method_data();
  1077   if (mdo == NULL)  return;
  1078   // There is a benign race here.  See comments in methodDataOop.hpp.
  1079   mdo->inc_decompile_count();
  1082 void nmethod::make_unloaded(BoolObjectClosure* is_alive, oop cause) {
  1084   post_compiled_method_unload();
  1086   // Since this nmethod is being unloaded, make sure that dependencies
  1087   // recorded in instanceKlasses get flushed and pass non-NULL closure to
  1088   // indicate that this work is being done during a GC.
  1089   assert(Universe::heap()->is_gc_active(), "should only be called during gc");
  1090   assert(is_alive != NULL, "Should be non-NULL");
  1091   // A non-NULL is_alive closure indicates that this is being called during GC.
  1092   flush_dependencies(is_alive);
  1094   // Break cycle between nmethod & method
  1095   if (TraceClassUnloading && WizardMode) {
  1096     tty->print_cr("[Class unloading: Making nmethod " INTPTR_FORMAT
  1097                   " unloadable], methodOop(" INTPTR_FORMAT
  1098                   "), cause(" INTPTR_FORMAT ")",
  1099                   this, (address)_method, (address)cause);
  1100     if (!Universe::heap()->is_gc_active())
  1101       cause->klass()->print();
  1103   // Unlink the osr method, so we do not look this up again
  1104   if (is_osr_method()) {
  1105     invalidate_osr_method();
  1107   // If _method is already NULL the methodOop is about to be unloaded,
  1108   // so we don't have to break the cycle. Note that it is possible to
  1109   // have the methodOop live here, in case we unload the nmethod because
  1110   // it is pointing to some oop (other than the methodOop) being unloaded.
  1111   if (_method != NULL) {
  1112     // OSR methods point to the methodOop, but the methodOop does not
  1113     // point back!
  1114     if (_method->code() == this) {
  1115       _method->clear_code(); // Break a cycle
  1117     inc_decompile_count();     // Last chance to make a mark on the MDO
  1118     _method = NULL;            // Clear the method of this dead nmethod
  1120   // Make the class unloaded - i.e., change state and notify sweeper
  1121   check_safepoint();
  1122   if (is_in_use()) {
  1123     // Transitioning directly from live to unloaded -- so
  1124     // we need to force a cache clean-up; remember this
  1125     // for later on.
  1126     CodeCache::set_needs_cache_clean(true);
  1128   flags.state = unloaded;
  1130   // Log the unloading.
  1131   log_state_change();
  1133   // The methodOop is gone at this point
  1134   assert(_method == NULL, "Tautology");
  1136   set_osr_link(NULL);
  1137   //set_scavenge_root_link(NULL); // done by prune_scavenge_root_nmethods
  1138   NMethodSweeper::notify(this);
  1141 void nmethod::invalidate_osr_method() {
  1142   assert(_entry_bci != InvocationEntryBci, "wrong kind of nmethod");
  1143   // Remove from list of active nmethods
  1144   if (method() != NULL)
  1145     instanceKlass::cast(method()->method_holder())->remove_osr_nmethod(this);
  1146   // Set entry as invalid
  1147   _entry_bci = InvalidOSREntryBci;
  1150 void nmethod::log_state_change() const {
  1151   if (LogCompilation) {
  1152     if (xtty != NULL) {
  1153       ttyLocker ttyl;  // keep the following output all in one block
  1154       if (flags.state == unloaded) {
  1155         xtty->begin_elem("make_unloaded thread='" UINTX_FORMAT "'",
  1156                          os::current_thread_id());
  1157       } else {
  1158         xtty->begin_elem("make_not_entrant thread='" UINTX_FORMAT "'%s",
  1159                          os::current_thread_id(),
  1160                          (flags.state == zombie ? " zombie='1'" : ""));
  1162       log_identity(xtty);
  1163       xtty->stamp();
  1164       xtty->end_elem();
  1167   if (PrintCompilation && flags.state != unloaded) {
  1168     print_on(tty, flags.state == zombie ? "made zombie " : "made not entrant ");
  1169     tty->cr();
  1173 // Common functionality for both make_not_entrant and make_zombie
  1174 bool nmethod::make_not_entrant_or_zombie(unsigned int state) {
  1175   assert(state == zombie || state == not_entrant, "must be zombie or not_entrant");
  1177   // If the method is already zombie there is nothing to do
  1178   if (is_zombie()) {
  1179     return false;
  1182   // Make sure the nmethod is not flushed in case of a safepoint in code below.
  1183   nmethodLocker nml(this);
  1186     // invalidate osr nmethod before acquiring the patching lock since
  1187     // they both acquire leaf locks and we don't want a deadlock.
  1188     // This logic is equivalent to the logic below for patching the
  1189     // verified entry point of regular methods.
  1190     if (is_osr_method()) {
  1191       // this effectively makes the osr nmethod not entrant
  1192       invalidate_osr_method();
  1195     // Enter critical section.  Does not block for safepoint.
  1196     MutexLockerEx pl(Patching_lock, Mutex::_no_safepoint_check_flag);
  1198     if (flags.state == state) {
  1199       // another thread already performed this transition so nothing
  1200       // to do, but return false to indicate this.
  1201       return false;
  1204     // The caller can be calling the method statically or through an inline
  1205     // cache call.
  1206     if (!is_osr_method() && !is_not_entrant()) {
  1207       NativeJump::patch_verified_entry(entry_point(), verified_entry_point(),
  1208                   SharedRuntime::get_handle_wrong_method_stub());
  1209       assert (NativeJump::instruction_size == nmethod::_zombie_instruction_size, "");
  1212     // When the nmethod becomes zombie it is no longer alive so the
  1213     // dependencies must be flushed.  nmethods in the not_entrant
  1214     // state will be flushed later when the transition to zombie
  1215     // happens or they get unloaded.
  1216     if (state == zombie) {
  1217       assert(SafepointSynchronize::is_at_safepoint(), "must be done at safepoint");
  1218       flush_dependencies(NULL);
  1219     } else {
  1220       assert(state == not_entrant, "other cases may need to be handled differently");
  1223     // Change state
  1224     flags.state = state;
  1226     // Log the transition once
  1227     log_state_change();
  1229   } // leave critical region under Patching_lock
  1231   if (state == not_entrant) {
  1232     Events::log("Make nmethod not entrant " INTPTR_FORMAT, this);
  1233   } else {
  1234     Events::log("Make nmethod zombie " INTPTR_FORMAT, this);
  1237   if (TraceCreateZombies) {
  1238     tty->print_cr("nmethod <" INTPTR_FORMAT "> code made %s", this, (state == not_entrant) ? "not entrant" : "zombie");
  1241   // Make sweeper aware that there is a zombie method that needs to be removed
  1242   NMethodSweeper::notify(this);
  1244   // not_entrant only stuff
  1245   if (state == not_entrant) {
  1246     mark_as_seen_on_stack();
  1249   // It's a true state change, so mark the method as decompiled.
  1250   inc_decompile_count();
  1252   // zombie only - if a JVMTI agent has enabled the CompiledMethodUnload event
  1253   // and it hasn't already been reported for this nmethod then report it now.
  1254   // (the event may have been reported earilier if the GC marked it for unloading).
  1255   if (state == zombie) {
  1257     DTRACE_METHOD_UNLOAD_PROBE(method());
  1259     if (JvmtiExport::should_post_compiled_method_unload() &&
  1260         !unload_reported()) {
  1261       assert(method() != NULL, "checking");
  1263         HandleMark hm;
  1264         JvmtiExport::post_compiled_method_unload_at_safepoint(
  1265             method()->jmethod_id(), code_begin());
  1267       set_unload_reported();
  1272   // Zombie only stuff
  1273   if (state == zombie) {
  1274     VTune::delete_nmethod(this);
  1277   // Check whether method got unloaded at a safepoint before this,
  1278   // if so we can skip the flushing steps below
  1279   if (method() == NULL) return true;
  1281   // Remove nmethod from method.
  1282   // We need to check if both the _code and _from_compiled_code_entry_point
  1283   // refer to this nmethod because there is a race in setting these two fields
  1284   // in methodOop as seen in bugid 4947125.
  1285   // If the vep() points to the zombie nmethod, the memory for the nmethod
  1286   // could be flushed and the compiler and vtable stubs could still call
  1287   // through it.
  1288   if (method()->code() == this ||
  1289       method()->from_compiled_entry() == verified_entry_point()) {
  1290     HandleMark hm;
  1291     method()->clear_code();
  1294   return true;
  1298 #ifndef PRODUCT
  1299 void nmethod::check_safepoint() {
  1300   assert(SafepointSynchronize::is_at_safepoint(), "must be at safepoint");
  1302 #endif
  1305 void nmethod::flush() {
  1306   // Note that there are no valid oops in the nmethod anymore.
  1307   assert(is_zombie() || (is_osr_method() && is_unloaded()), "must be a zombie method");
  1308   assert(is_marked_for_reclamation() || (is_osr_method() && is_unloaded()), "must be marked for reclamation");
  1310   assert (!is_locked_by_vm(), "locked methods shouldn't be flushed");
  1311   check_safepoint();
  1313   // completely deallocate this method
  1314   EventMark m("flushing nmethod " INTPTR_FORMAT " %s", this, "");
  1315   if (PrintMethodFlushing) {
  1316     tty->print_cr("*flushing nmethod %3d/" INTPTR_FORMAT ". Live blobs:" UINT32_FORMAT "/Free CodeCache:" SIZE_FORMAT "Kb",
  1317         _compile_id, this, CodeCache::nof_blobs(), CodeCache::unallocated_capacity()/1024);
  1320   // We need to deallocate any ExceptionCache data.
  1321   // Note that we do not need to grab the nmethod lock for this, it
  1322   // better be thread safe if we're disposing of it!
  1323   ExceptionCache* ec = exception_cache();
  1324   set_exception_cache(NULL);
  1325   while(ec != NULL) {
  1326     ExceptionCache* next = ec->next();
  1327     delete ec;
  1328     ec = next;
  1331   if (on_scavenge_root_list()) {
  1332     CodeCache::drop_scavenge_root_nmethod(this);
  1335   if (is_speculatively_disconnected()) {
  1336     CodeCache::remove_saved_code(this);
  1339   ((CodeBlob*)(this))->flush();
  1341   CodeCache::free(this);
  1345 //
  1346 // Notify all classes this nmethod is dependent on that it is no
  1347 // longer dependent. This should only be called in two situations.
  1348 // First, when a nmethod transitions to a zombie all dependents need
  1349 // to be clear.  Since zombification happens at a safepoint there's no
  1350 // synchronization issues.  The second place is a little more tricky.
  1351 // During phase 1 of mark sweep class unloading may happen and as a
  1352 // result some nmethods may get unloaded.  In this case the flushing
  1353 // of dependencies must happen during phase 1 since after GC any
  1354 // dependencies in the unloaded nmethod won't be updated, so
  1355 // traversing the dependency information in unsafe.  In that case this
  1356 // function is called with a non-NULL argument and this function only
  1357 // notifies instanceKlasses that are reachable
  1359 void nmethod::flush_dependencies(BoolObjectClosure* is_alive) {
  1360   assert(SafepointSynchronize::is_at_safepoint(), "must be done at safepoint");
  1361   assert(Universe::heap()->is_gc_active() == (is_alive != NULL),
  1362   "is_alive is non-NULL if and only if we are called during GC");
  1363   if (!has_flushed_dependencies()) {
  1364     set_has_flushed_dependencies();
  1365     for (Dependencies::DepStream deps(this); deps.next(); ) {
  1366       klassOop klass = deps.context_type();
  1367       if (klass == NULL)  continue;  // ignore things like evol_method
  1369       // During GC the is_alive closure is non-NULL, and is used to
  1370       // determine liveness of dependees that need to be updated.
  1371       if (is_alive == NULL || is_alive->do_object_b(klass)) {
  1372         instanceKlass::cast(klass)->remove_dependent_nmethod(this);
  1379 // If this oop is not live, the nmethod can be unloaded.
  1380 bool nmethod::can_unload(BoolObjectClosure* is_alive,
  1381                          OopClosure* keep_alive,
  1382                          oop* root, bool unloading_occurred) {
  1383   assert(root != NULL, "just checking");
  1384   oop obj = *root;
  1385   if (obj == NULL || is_alive->do_object_b(obj)) {
  1386       return false;
  1388   if (obj->is_compiledICHolder()) {
  1389     compiledICHolderOop cichk_oop = compiledICHolderOop(obj);
  1390     if (is_alive->do_object_b(
  1391           cichk_oop->holder_method()->method_holder()) &&
  1392         is_alive->do_object_b(cichk_oop->holder_klass())) {
  1393       // The oop should be kept alive
  1394       keep_alive->do_oop(root);
  1395       return false;
  1398   // If ScavengeRootsInCode is true, an nmethod might be unloaded
  1399   // simply because one of its constant oops has gone dead.
  1400   // No actual classes need to be unloaded in order for this to occur.
  1401   assert(unloading_occurred || ScavengeRootsInCode, "Inconsistency in unloading");
  1402   make_unloaded(is_alive, obj);
  1403   return true;
  1406 // ------------------------------------------------------------------
  1407 // post_compiled_method_load_event
  1408 // new method for install_code() path
  1409 // Transfer information from compilation to jvmti
  1410 void nmethod::post_compiled_method_load_event() {
  1412   methodOop moop = method();
  1413   HS_DTRACE_PROBE8(hotspot, compiled__method__load,
  1414       moop->klass_name()->bytes(),
  1415       moop->klass_name()->utf8_length(),
  1416       moop->name()->bytes(),
  1417       moop->name()->utf8_length(),
  1418       moop->signature()->bytes(),
  1419       moop->signature()->utf8_length(),
  1420       code_begin(), code_size());
  1422   if (JvmtiExport::should_post_compiled_method_load()) {
  1423     JvmtiExport::post_compiled_method_load(this);
  1427 void nmethod::post_compiled_method_unload() {
  1428   assert(_method != NULL && !is_unloaded(), "just checking");
  1429   DTRACE_METHOD_UNLOAD_PROBE(method());
  1431   // If a JVMTI agent has enabled the CompiledMethodUnload event then
  1432   // post the event. Sometime later this nmethod will be made a zombie by
  1433   // the sweeper but the methodOop will not be valid at that point.
  1434   if (JvmtiExport::should_post_compiled_method_unload()) {
  1435     assert(!unload_reported(), "already unloaded");
  1436     HandleMark hm;
  1437     JvmtiExport::post_compiled_method_unload_at_safepoint(
  1438                       method()->jmethod_id(), code_begin());
  1441   // The JVMTI CompiledMethodUnload event can be enabled or disabled at
  1442   // any time. As the nmethod is being unloaded now we mark it has
  1443   // having the unload event reported - this will ensure that we don't
  1444   // attempt to report the event in the unlikely scenario where the
  1445   // event is enabled at the time the nmethod is made a zombie.
  1446   set_unload_reported();
  1449 // This is called at the end of the strong tracing/marking phase of a
  1450 // GC to unload an nmethod if it contains otherwise unreachable
  1451 // oops.
  1453 void nmethod::do_unloading(BoolObjectClosure* is_alive,
  1454                            OopClosure* keep_alive, bool unloading_occurred) {
  1455   // Make sure the oop's ready to receive visitors
  1456   assert(!is_zombie() && !is_unloaded(),
  1457          "should not call follow on zombie or unloaded nmethod");
  1459   // If the method is not entrant then a JMP is plastered over the
  1460   // first few bytes.  If an oop in the old code was there, that oop
  1461   // should not get GC'd.  Skip the first few bytes of oops on
  1462   // not-entrant methods.
  1463   address low_boundary = verified_entry_point();
  1464   if (is_not_entrant()) {
  1465     low_boundary += NativeJump::instruction_size;
  1466     // %%% Note:  On SPARC we patch only a 4-byte trap, not a full NativeJump.
  1467     // (See comment above.)
  1470   // The RedefineClasses() API can cause the class unloading invariant
  1471   // to no longer be true. See jvmtiExport.hpp for details.
  1472   // Also, leave a debugging breadcrumb in local flag.
  1473   bool a_class_was_redefined = JvmtiExport::has_redefined_a_class();
  1474   if (a_class_was_redefined) {
  1475     // This set of the unloading_occurred flag is done before the
  1476     // call to post_compiled_method_unload() so that the unloading
  1477     // of this nmethod is reported.
  1478     unloading_occurred = true;
  1481   // Follow methodOop
  1482   if (can_unload(is_alive, keep_alive, (oop*)&_method, unloading_occurred)) {
  1483     return;
  1486   // Exception cache
  1487   ExceptionCache* ec = exception_cache();
  1488   while (ec != NULL) {
  1489     oop* ex_addr = (oop*)ec->exception_type_addr();
  1490     oop ex = *ex_addr;
  1491     ExceptionCache* next_ec = ec->next();
  1492     if (ex != NULL && !is_alive->do_object_b(ex)) {
  1493       assert(!ex->is_compiledICHolder(), "Possible error here");
  1494       remove_from_exception_cache(ec);
  1496     ec = next_ec;
  1499   // If class unloading occurred we first iterate over all inline caches and
  1500   // clear ICs where the cached oop is referring to an unloaded klass or method.
  1501   // The remaining live cached oops will be traversed in the relocInfo::oop_type
  1502   // iteration below.
  1503   if (unloading_occurred) {
  1504     RelocIterator iter(this, low_boundary);
  1505     while(iter.next()) {
  1506       if (iter.type() == relocInfo::virtual_call_type) {
  1507         CompiledIC *ic = CompiledIC_at(iter.reloc());
  1508         oop ic_oop = ic->cached_oop();
  1509         if (ic_oop != NULL && !is_alive->do_object_b(ic_oop)) {
  1510           // The only exception is compiledICHolder oops which may
  1511           // yet be marked below. (We check this further below).
  1512           if (ic_oop->is_compiledICHolder()) {
  1513             compiledICHolderOop cichk_oop = compiledICHolderOop(ic_oop);
  1514             if (is_alive->do_object_b(
  1515                   cichk_oop->holder_method()->method_holder()) &&
  1516                 is_alive->do_object_b(cichk_oop->holder_klass())) {
  1517               continue;
  1520           ic->set_to_clean();
  1521           assert(ic->cached_oop() == NULL, "cached oop in IC should be cleared")
  1527   // Compiled code
  1528   RelocIterator iter(this, low_boundary);
  1529   while (iter.next()) {
  1530     if (iter.type() == relocInfo::oop_type) {
  1531       oop_Relocation* r = iter.oop_reloc();
  1532       // In this loop, we must only traverse those oops directly embedded in
  1533       // the code.  Other oops (oop_index>0) are seen as part of scopes_oops.
  1534       assert(1 == (r->oop_is_immediate()) +
  1535                   (r->oop_addr() >= oops_begin() && r->oop_addr() < oops_end()),
  1536              "oop must be found in exactly one place");
  1537       if (r->oop_is_immediate() && r->oop_value() != NULL) {
  1538         if (can_unload(is_alive, keep_alive, r->oop_addr(), unloading_occurred)) {
  1539           return;
  1546   // Scopes
  1547   for (oop* p = oops_begin(); p < oops_end(); p++) {
  1548     if (*p == Universe::non_oop_word())  continue;  // skip non-oops
  1549     if (can_unload(is_alive, keep_alive, p, unloading_occurred)) {
  1550       return;
  1554 #ifndef PRODUCT
  1555   // This nmethod was not unloaded; check below that all CompiledICs
  1556   // refer to marked oops.
  1558     RelocIterator iter(this, low_boundary);
  1559     while (iter.next()) {
  1560       if (iter.type() == relocInfo::virtual_call_type) {
  1561          CompiledIC *ic = CompiledIC_at(iter.reloc());
  1562          oop ic_oop = ic->cached_oop();
  1563          assert(ic_oop == NULL || is_alive->do_object_b(ic_oop),
  1564                 "Found unmarked ic_oop in reachable nmethod");
  1568 #endif // !PRODUCT
  1571 // This method is called twice during GC -- once while
  1572 // tracing the "active" nmethods on thread stacks during
  1573 // the (strong) marking phase, and then again when walking
  1574 // the code cache contents during the weak roots processing
  1575 // phase. The two uses are distinguished by means of the
  1576 // 'do_strong_roots_only' flag, which is true in the first
  1577 // case. We want to walk the weak roots in the nmethod
  1578 // only in the second case. The weak roots in the nmethod
  1579 // are the oops in the ExceptionCache and the InlineCache
  1580 // oops.
  1581 void nmethod::oops_do(OopClosure* f, bool do_strong_roots_only) {
  1582   // make sure the oops ready to receive visitors
  1583   assert(!is_zombie() && !is_unloaded(),
  1584          "should not call follow on zombie or unloaded nmethod");
  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.)
  1597   // Compiled code
  1598   f->do_oop((oop*) &_method);
  1599   if (!do_strong_roots_only) {
  1600     // weak roots processing phase -- update ExceptionCache oops
  1601     ExceptionCache* ec = exception_cache();
  1602     while(ec != NULL) {
  1603       f->do_oop((oop*)ec->exception_type_addr());
  1604       ec = ec->next();
  1606   } // Else strong roots phase -- skip oops in ExceptionCache
  1608   RelocIterator iter(this, low_boundary);
  1610   while (iter.next()) {
  1611     if (iter.type() == relocInfo::oop_type ) {
  1612       oop_Relocation* r = iter.oop_reloc();
  1613       // In this loop, we must only follow those oops directly embedded in
  1614       // the code.  Other oops (oop_index>0) are seen as part of scopes_oops.
  1615       assert(1 == (r->oop_is_immediate()) +
  1616                    (r->oop_addr() >= oops_begin() && r->oop_addr() < oops_end()),
  1617              "oop must be found in exactly one place");
  1618       if (r->oop_is_immediate() && r->oop_value() != NULL) {
  1619         f->do_oop(r->oop_addr());
  1624   // Scopes
  1625   // This includes oop constants not inlined in the code stream.
  1626   for (oop* p = oops_begin(); p < oops_end(); p++) {
  1627     if (*p == Universe::non_oop_word())  continue;  // skip non-oops
  1628     f->do_oop(p);
  1632 #define NMETHOD_SENTINEL ((nmethod*)badAddress)
  1634 nmethod* volatile nmethod::_oops_do_mark_nmethods;
  1636 // An nmethod is "marked" if its _mark_link is set non-null.
  1637 // Even if it is the end of the linked list, it will have a non-null link value,
  1638 // as long as it is on the list.
  1639 // This code must be MP safe, because it is used from parallel GC passes.
  1640 bool nmethod::test_set_oops_do_mark() {
  1641   assert(nmethod::oops_do_marking_is_active(), "oops_do_marking_prologue must be called");
  1642   nmethod* observed_mark_link = _oops_do_mark_link;
  1643   if (observed_mark_link == NULL) {
  1644     // Claim this nmethod for this thread to mark.
  1645     observed_mark_link = (nmethod*)
  1646       Atomic::cmpxchg_ptr(NMETHOD_SENTINEL, &_oops_do_mark_link, NULL);
  1647     if (observed_mark_link == NULL) {
  1649       // Atomically append this nmethod (now claimed) to the head of the list:
  1650       nmethod* observed_mark_nmethods = _oops_do_mark_nmethods;
  1651       for (;;) {
  1652         nmethod* required_mark_nmethods = observed_mark_nmethods;
  1653         _oops_do_mark_link = required_mark_nmethods;
  1654         observed_mark_nmethods = (nmethod*)
  1655           Atomic::cmpxchg_ptr(this, &_oops_do_mark_nmethods, required_mark_nmethods);
  1656         if (observed_mark_nmethods == required_mark_nmethods)
  1657           break;
  1659       // Mark was clear when we first saw this guy.
  1660       NOT_PRODUCT(if (TraceScavenge)  print_on(tty, "oops_do, mark\n"));
  1661       return false;
  1664   // On fall through, another racing thread marked this nmethod before we did.
  1665   return true;
  1668 void nmethod::oops_do_marking_prologue() {
  1669   NOT_PRODUCT(if (TraceScavenge)  tty->print_cr("[oops_do_marking_prologue"));
  1670   assert(_oops_do_mark_nmethods == NULL, "must not call oops_do_marking_prologue twice in a row");
  1671   // We use cmpxchg_ptr instead of regular assignment here because the user
  1672   // may fork a bunch of threads, and we need them all to see the same state.
  1673   void* observed = Atomic::cmpxchg_ptr(NMETHOD_SENTINEL, &_oops_do_mark_nmethods, NULL);
  1674   guarantee(observed == NULL, "no races in this sequential code");
  1677 void nmethod::oops_do_marking_epilogue() {
  1678   assert(_oops_do_mark_nmethods != NULL, "must not call oops_do_marking_epilogue twice in a row");
  1679   nmethod* cur = _oops_do_mark_nmethods;
  1680   while (cur != NMETHOD_SENTINEL) {
  1681     assert(cur != NULL, "not NULL-terminated");
  1682     nmethod* next = cur->_oops_do_mark_link;
  1683     cur->_oops_do_mark_link = NULL;
  1684     NOT_PRODUCT(if (TraceScavenge)  cur->print_on(tty, "oops_do, unmark\n"));
  1685     cur = next;
  1687   void* required = _oops_do_mark_nmethods;
  1688   void* observed = Atomic::cmpxchg_ptr(NULL, &_oops_do_mark_nmethods, required);
  1689   guarantee(observed == required, "no races in this sequential code");
  1690   NOT_PRODUCT(if (TraceScavenge)  tty->print_cr("oops_do_marking_epilogue]"));
  1693 class DetectScavengeRoot: public OopClosure {
  1694   bool     _detected_scavenge_root;
  1695 public:
  1696   DetectScavengeRoot() : _detected_scavenge_root(false)
  1697   { NOT_PRODUCT(_print_nm = NULL); }
  1698   bool detected_scavenge_root() { return _detected_scavenge_root; }
  1699   virtual void do_oop(oop* p) {
  1700     if ((*p) != NULL && (*p)->is_scavengable()) {
  1701       NOT_PRODUCT(maybe_print(p));
  1702       _detected_scavenge_root = true;
  1705   virtual void do_oop(narrowOop* p) { ShouldNotReachHere(); }
  1707 #ifndef PRODUCT
  1708   nmethod* _print_nm;
  1709   void maybe_print(oop* p) {
  1710     if (_print_nm == NULL)  return;
  1711     if (!_detected_scavenge_root)  _print_nm->print_on(tty, "new scavenge root");
  1712     tty->print_cr(""PTR_FORMAT"[offset=%d] detected non-perm oop "PTR_FORMAT" (found at "PTR_FORMAT")",
  1713                   _print_nm, (int)((intptr_t)p - (intptr_t)_print_nm),
  1714                   (intptr_t)(*p), (intptr_t)p);
  1715     (*p)->print();
  1717 #endif //PRODUCT
  1718 };
  1720 bool nmethod::detect_scavenge_root_oops() {
  1721   DetectScavengeRoot detect_scavenge_root;
  1722   NOT_PRODUCT(if (TraceScavenge)  detect_scavenge_root._print_nm = this);
  1723   oops_do(&detect_scavenge_root);
  1724   return detect_scavenge_root.detected_scavenge_root();
  1727 // Method that knows how to preserve outgoing arguments at call. This method must be
  1728 // called with a frame corresponding to a Java invoke
  1729 void nmethod::preserve_callee_argument_oops(frame fr, const RegisterMap *reg_map, OopClosure* f) {
  1730   if (!method()->is_native()) {
  1731     SimpleScopeDesc ssd(this, fr.pc());
  1732     Bytecode_invoke* call = Bytecode_invoke_at(ssd.method(), ssd.bci());
  1733     bool has_receiver = call->has_receiver();
  1734     symbolOop signature = call->signature();
  1735     fr.oops_compiled_arguments_do(signature, has_receiver, reg_map, f);
  1740 oop nmethod::embeddedOop_at(u_char* p) {
  1741   RelocIterator iter(this, p, p + oopSize);
  1742   while (iter.next())
  1743     if (iter.type() == relocInfo::oop_type) {
  1744       return iter.oop_reloc()->oop_value();
  1746   return NULL;
  1750 inline bool includes(void* p, void* from, void* to) {
  1751   return from <= p && p < to;
  1755 void nmethod::copy_scopes_pcs(PcDesc* pcs, int count) {
  1756   assert(count >= 2, "must be sentinel values, at least");
  1758 #ifdef ASSERT
  1759   // must be sorted and unique; we do a binary search in find_pc_desc()
  1760   int prev_offset = pcs[0].pc_offset();
  1761   assert(prev_offset == PcDesc::lower_offset_limit,
  1762          "must start with a sentinel");
  1763   for (int i = 1; i < count; i++) {
  1764     int this_offset = pcs[i].pc_offset();
  1765     assert(this_offset > prev_offset, "offsets must be sorted");
  1766     prev_offset = this_offset;
  1768   assert(prev_offset == PcDesc::upper_offset_limit,
  1769          "must end with a sentinel");
  1770 #endif //ASSERT
  1772   // Search for MethodHandle invokes and tag the nmethod.
  1773   for (int i = 0; i < count; i++) {
  1774     if (pcs[i].is_method_handle_invoke()) {
  1775       set_has_method_handle_invokes(true);
  1776       break;
  1780   int size = count * sizeof(PcDesc);
  1781   assert(scopes_pcs_size() >= size, "oob");
  1782   memcpy(scopes_pcs_begin(), pcs, size);
  1784   // Adjust the final sentinel downward.
  1785   PcDesc* last_pc = &scopes_pcs_begin()[count-1];
  1786   assert(last_pc->pc_offset() == PcDesc::upper_offset_limit, "sanity");
  1787   last_pc->set_pc_offset(instructions_size() + 1);
  1788   for (; last_pc + 1 < scopes_pcs_end(); last_pc += 1) {
  1789     // Fill any rounding gaps with copies of the last record.
  1790     last_pc[1] = last_pc[0];
  1792   // The following assert could fail if sizeof(PcDesc) is not
  1793   // an integral multiple of oopSize (the rounding term).
  1794   // If it fails, change the logic to always allocate a multiple
  1795   // of sizeof(PcDesc), and fill unused words with copies of *last_pc.
  1796   assert(last_pc + 1 == scopes_pcs_end(), "must match exactly");
  1799 void nmethod::copy_scopes_data(u_char* buffer, int size) {
  1800   assert(scopes_data_size() >= size, "oob");
  1801   memcpy(scopes_data_begin(), buffer, size);
  1805 #ifdef ASSERT
  1806 static PcDesc* linear_search(nmethod* nm, int pc_offset, bool approximate) {
  1807   PcDesc* lower = nm->scopes_pcs_begin();
  1808   PcDesc* upper = nm->scopes_pcs_end();
  1809   lower += 1; // exclude initial sentinel
  1810   PcDesc* res = NULL;
  1811   for (PcDesc* p = lower; p < upper; p++) {
  1812     NOT_PRODUCT(--nmethod_stats.pc_desc_tests);  // don't count this call to match_desc
  1813     if (match_desc(p, pc_offset, approximate)) {
  1814       if (res == NULL)
  1815         res = p;
  1816       else
  1817         res = (PcDesc*) badAddress;
  1820   return res;
  1822 #endif
  1825 // Finds a PcDesc with real-pc equal to "pc"
  1826 PcDesc* nmethod::find_pc_desc_internal(address pc, bool approximate) {
  1827   address base_address = instructions_begin();
  1828   if ((pc < base_address) ||
  1829       (pc - base_address) >= (ptrdiff_t) PcDesc::upper_offset_limit) {
  1830     return NULL;  // PC is wildly out of range
  1832   int pc_offset = (int) (pc - base_address);
  1834   // Check the PcDesc cache if it contains the desired PcDesc
  1835   // (This as an almost 100% hit rate.)
  1836   PcDesc* res = _pc_desc_cache.find_pc_desc(pc_offset, approximate);
  1837   if (res != NULL) {
  1838     assert(res == linear_search(this, pc_offset, approximate), "cache ok");
  1839     return res;
  1842   // Fallback algorithm: quasi-linear search for the PcDesc
  1843   // Find the last pc_offset less than the given offset.
  1844   // The successor must be the required match, if there is a match at all.
  1845   // (Use a fixed radix to avoid expensive affine pointer arithmetic.)
  1846   PcDesc* lower = scopes_pcs_begin();
  1847   PcDesc* upper = scopes_pcs_end();
  1848   upper -= 1; // exclude final sentinel
  1849   if (lower >= upper)  return NULL;  // native method; no PcDescs at all
  1851 #define assert_LU_OK \
  1852   /* invariant on lower..upper during the following search: */ \
  1853   assert(lower->pc_offset() <  pc_offset, "sanity"); \
  1854   assert(upper->pc_offset() >= pc_offset, "sanity")
  1855   assert_LU_OK;
  1857   // Use the last successful return as a split point.
  1858   PcDesc* mid = _pc_desc_cache.last_pc_desc();
  1859   NOT_PRODUCT(++nmethod_stats.pc_desc_searches);
  1860   if (mid->pc_offset() < pc_offset) {
  1861     lower = mid;
  1862   } else {
  1863     upper = mid;
  1866   // Take giant steps at first (4096, then 256, then 16, then 1)
  1867   const int LOG2_RADIX = 4 /*smaller steps in debug mode:*/ debug_only(-1);
  1868   const int RADIX = (1 << LOG2_RADIX);
  1869   for (int step = (1 << (LOG2_RADIX*3)); step > 1; step >>= LOG2_RADIX) {
  1870     while ((mid = lower + step) < upper) {
  1871       assert_LU_OK;
  1872       NOT_PRODUCT(++nmethod_stats.pc_desc_searches);
  1873       if (mid->pc_offset() < pc_offset) {
  1874         lower = mid;
  1875       } else {
  1876         upper = mid;
  1877         break;
  1880     assert_LU_OK;
  1883   // Sneak up on the value with a linear search of length ~16.
  1884   while (true) {
  1885     assert_LU_OK;
  1886     mid = lower + 1;
  1887     NOT_PRODUCT(++nmethod_stats.pc_desc_searches);
  1888     if (mid->pc_offset() < pc_offset) {
  1889       lower = mid;
  1890     } else {
  1891       upper = mid;
  1892       break;
  1895 #undef assert_LU_OK
  1897   if (match_desc(upper, pc_offset, approximate)) {
  1898     assert(upper == linear_search(this, pc_offset, approximate), "search ok");
  1899     _pc_desc_cache.add_pc_desc(upper);
  1900     return upper;
  1901   } else {
  1902     assert(NULL == linear_search(this, pc_offset, approximate), "search ok");
  1903     return NULL;
  1908 bool nmethod::check_all_dependencies() {
  1909   bool found_check = false;
  1910   // wholesale check of all dependencies
  1911   for (Dependencies::DepStream deps(this); deps.next(); ) {
  1912     if (deps.check_dependency() != NULL) {
  1913       found_check = true;
  1914       NOT_DEBUG(break);
  1917   return found_check;  // tell caller if we found anything
  1920 bool nmethod::check_dependency_on(DepChange& changes) {
  1921   // What has happened:
  1922   // 1) a new class dependee has been added
  1923   // 2) dependee and all its super classes have been marked
  1924   bool found_check = false;  // set true if we are upset
  1925   for (Dependencies::DepStream deps(this); deps.next(); ) {
  1926     // Evaluate only relevant dependencies.
  1927     if (deps.spot_check_dependency_at(changes) != NULL) {
  1928       found_check = true;
  1929       NOT_DEBUG(break);
  1932   return found_check;
  1935 bool nmethod::is_evol_dependent_on(klassOop dependee) {
  1936   instanceKlass *dependee_ik = instanceKlass::cast(dependee);
  1937   objArrayOop dependee_methods = dependee_ik->methods();
  1938   for (Dependencies::DepStream deps(this); deps.next(); ) {
  1939     if (deps.type() == Dependencies::evol_method) {
  1940       methodOop method = deps.method_argument(0);
  1941       for (int j = 0; j < dependee_methods->length(); j++) {
  1942         if ((methodOop) dependee_methods->obj_at(j) == method) {
  1943           // RC_TRACE macro has an embedded ResourceMark
  1944           RC_TRACE(0x01000000,
  1945             ("Found evol dependency of nmethod %s.%s(%s) compile_id=%d on method %s.%s(%s)",
  1946             _method->method_holder()->klass_part()->external_name(),
  1947             _method->name()->as_C_string(),
  1948             _method->signature()->as_C_string(), compile_id(),
  1949             method->method_holder()->klass_part()->external_name(),
  1950             method->name()->as_C_string(),
  1951             method->signature()->as_C_string()));
  1952           if (TraceDependencies || LogCompilation)
  1953             deps.log_dependency(dependee);
  1954           return true;
  1959   return false;
  1962 // Called from mark_for_deoptimization, when dependee is invalidated.
  1963 bool nmethod::is_dependent_on_method(methodOop dependee) {
  1964   for (Dependencies::DepStream deps(this); deps.next(); ) {
  1965     if (deps.type() != Dependencies::evol_method)
  1966       continue;
  1967     methodOop method = deps.method_argument(0);
  1968     if (method == dependee) return true;
  1970   return false;
  1974 bool nmethod::is_patchable_at(address instr_addr) {
  1975   assert (code_contains(instr_addr), "wrong nmethod used");
  1976   if (is_zombie()) {
  1977     // a zombie may never be patched
  1978     return false;
  1980   return true;
  1984 address nmethod::continuation_for_implicit_exception(address pc) {
  1985   // Exception happened outside inline-cache check code => we are inside
  1986   // an active nmethod => use cpc to determine a return address
  1987   int exception_offset = pc - instructions_begin();
  1988   int cont_offset = ImplicitExceptionTable(this).at( exception_offset );
  1989 #ifdef ASSERT
  1990   if (cont_offset == 0) {
  1991     Thread* thread = ThreadLocalStorage::get_thread_slow();
  1992     ResetNoHandleMark rnm; // Might be called from LEAF/QUICK ENTRY
  1993     HandleMark hm(thread);
  1994     ResourceMark rm(thread);
  1995     CodeBlob* cb = CodeCache::find_blob(pc);
  1996     assert(cb != NULL && cb == this, "");
  1997     tty->print_cr("implicit exception happened at " INTPTR_FORMAT, pc);
  1998     print();
  1999     method()->print_codes();
  2000     print_code();
  2001     print_pcs();
  2003 #endif
  2004   guarantee(cont_offset != 0, "unhandled implicit exception in compiled code");
  2005   return instructions_begin() + cont_offset;
  2010 void nmethod_init() {
  2011   // make sure you didn't forget to adjust the filler fields
  2012   assert(sizeof(nmFlags) <= 4,           "nmFlags occupies more than a word");
  2013   assert(sizeof(nmethod) % oopSize == 0, "nmethod size must be multiple of a word");
  2017 //-------------------------------------------------------------------------------------------
  2020 // QQQ might we make this work from a frame??
  2021 nmethodLocker::nmethodLocker(address pc) {
  2022   CodeBlob* cb = CodeCache::find_blob(pc);
  2023   guarantee(cb != NULL && cb->is_nmethod(), "bad pc for a nmethod found");
  2024   _nm = (nmethod*)cb;
  2025   lock_nmethod(_nm);
  2028 void nmethodLocker::lock_nmethod(nmethod* nm) {
  2029   if (nm == NULL)  return;
  2030   Atomic::inc(&nm->_lock_count);
  2031   guarantee(!nm->is_zombie(), "cannot lock a zombie method");
  2034 void nmethodLocker::unlock_nmethod(nmethod* nm) {
  2035   if (nm == NULL)  return;
  2036   Atomic::dec(&nm->_lock_count);
  2037   guarantee(nm->_lock_count >= 0, "unmatched nmethod lock/unlock");
  2040 bool nmethod::is_deopt_pc(address pc) {
  2041   bool ret =  pc == deopt_handler_begin();
  2042   return ret;
  2046 // -----------------------------------------------------------------------------
  2047 // MethodHandle
  2049 bool nmethod::is_method_handle_return(address return_pc) {
  2050   if (!has_method_handle_invokes())  return false;
  2051   PcDesc* pd = pc_desc_at(return_pc);
  2052   if (pd == NULL)
  2053     return false;
  2054   return pd->is_method_handle_invoke();
  2058 // -----------------------------------------------------------------------------
  2059 // Verification
  2061 class VerifyOopsClosure: public OopClosure {
  2062   nmethod* _nm;
  2063   bool     _ok;
  2064 public:
  2065   VerifyOopsClosure(nmethod* nm) : _nm(nm), _ok(true) { }
  2066   bool ok() { return _ok; }
  2067   virtual void do_oop(oop* p) {
  2068     if ((*p) == NULL || (*p)->is_oop())  return;
  2069     if (_ok) {
  2070       _nm->print_nmethod(true);
  2071       _ok = false;
  2073     tty->print_cr("*** non-oop "PTR_FORMAT" found at "PTR_FORMAT" (offset %d)",
  2074                   (intptr_t)(*p), (intptr_t)p, (int)((intptr_t)p - (intptr_t)_nm));
  2076   virtual void do_oop(narrowOop* p) { ShouldNotReachHere(); }
  2077 };
  2079 void nmethod::verify() {
  2081   // Hmm. OSR methods can be deopted but not marked as zombie or not_entrant
  2082   // seems odd.
  2084   if( is_zombie() || is_not_entrant() )
  2085     return;
  2087   // Make sure all the entry points are correctly aligned for patching.
  2088   NativeJump::check_verified_entry_alignment(entry_point(), verified_entry_point());
  2090   assert(method()->is_oop(), "must be valid");
  2092   ResourceMark rm;
  2094   if (!CodeCache::contains(this)) {
  2095     fatal1("nmethod at " INTPTR_FORMAT " not in zone", this);
  2098   if(is_native_method() )
  2099     return;
  2101   nmethod* nm = CodeCache::find_nmethod(verified_entry_point());
  2102   if (nm != this) {
  2103     fatal1("findNMethod did not find this nmethod (" INTPTR_FORMAT ")", this);
  2106   for (PcDesc* p = scopes_pcs_begin(); p < scopes_pcs_end(); p++) {
  2107     if (! p->verify(this)) {
  2108       tty->print_cr("\t\tin nmethod at " INTPTR_FORMAT " (pcs)", this);
  2112   VerifyOopsClosure voc(this);
  2113   oops_do(&voc);
  2114   assert(voc.ok(), "embedded oops must be OK");
  2115   verify_scavenge_root_oops();
  2117   verify_scopes();
  2121 void nmethod::verify_interrupt_point(address call_site) {
  2122   // This code does not work in release mode since
  2123   // owns_lock only is available in debug mode.
  2124   CompiledIC* ic = NULL;
  2125   Thread *cur = Thread::current();
  2126   if (CompiledIC_lock->owner() == cur ||
  2127       ((cur->is_VM_thread() || cur->is_ConcurrentGC_thread()) &&
  2128        SafepointSynchronize::is_at_safepoint())) {
  2129     ic = CompiledIC_at(call_site);
  2130     CHECK_UNHANDLED_OOPS_ONLY(Thread::current()->clear_unhandled_oops());
  2131   } else {
  2132     MutexLocker ml_verify (CompiledIC_lock);
  2133     ic = CompiledIC_at(call_site);
  2135   PcDesc* pd = pc_desc_at(ic->end_of_call());
  2136   assert(pd != NULL, "PcDesc must exist");
  2137   for (ScopeDesc* sd = new ScopeDesc(this, pd->scope_decode_offset(),
  2138                                      pd->obj_decode_offset(), pd->should_reexecute());
  2139        !sd->is_top(); sd = sd->sender()) {
  2140     sd->verify();
  2144 void nmethod::verify_scopes() {
  2145   if( !method() ) return;       // Runtime stubs have no scope
  2146   if (method()->is_native()) return; // Ignore stub methods.
  2147   // iterate through all interrupt point
  2148   // and verify the debug information is valid.
  2149   RelocIterator iter((nmethod*)this);
  2150   while (iter.next()) {
  2151     address stub = NULL;
  2152     switch (iter.type()) {
  2153       case relocInfo::virtual_call_type:
  2154         verify_interrupt_point(iter.addr());
  2155         break;
  2156       case relocInfo::opt_virtual_call_type:
  2157         stub = iter.opt_virtual_call_reloc()->static_stub();
  2158         verify_interrupt_point(iter.addr());
  2159         break;
  2160       case relocInfo::static_call_type:
  2161         stub = iter.static_call_reloc()->static_stub();
  2162         //verify_interrupt_point(iter.addr());
  2163         break;
  2164       case relocInfo::runtime_call_type:
  2165         address destination = iter.reloc()->value();
  2166         // Right now there is no way to find out which entries support
  2167         // an interrupt point.  It would be nice if we had this
  2168         // information in a table.
  2169         break;
  2171     assert(stub == NULL || stub_contains(stub), "static call stub outside stub section");
  2176 // -----------------------------------------------------------------------------
  2177 // Non-product code
  2178 #ifndef PRODUCT
  2180 class DebugScavengeRoot: public OopClosure {
  2181   nmethod* _nm;
  2182   bool     _ok;
  2183 public:
  2184   DebugScavengeRoot(nmethod* nm) : _nm(nm), _ok(true) { }
  2185   bool ok() { return _ok; }
  2186   virtual void do_oop(oop* p) {
  2187     if ((*p) == NULL || !(*p)->is_scavengable())  return;
  2188     if (_ok) {
  2189       _nm->print_nmethod(true);
  2190       _ok = false;
  2192     tty->print_cr("*** non-perm oop "PTR_FORMAT" found at "PTR_FORMAT" (offset %d)",
  2193                   (intptr_t)(*p), (intptr_t)p, (int)((intptr_t)p - (intptr_t)_nm));
  2194     (*p)->print();
  2196   virtual void do_oop(narrowOop* p) { ShouldNotReachHere(); }
  2197 };
  2199 void nmethod::verify_scavenge_root_oops() {
  2200   if (!on_scavenge_root_list()) {
  2201     // Actually look inside, to verify the claim that it's clean.
  2202     DebugScavengeRoot debug_scavenge_root(this);
  2203     oops_do(&debug_scavenge_root);
  2204     if (!debug_scavenge_root.ok())
  2205       fatal("found an unadvertised bad non-perm oop in the code cache");
  2207   assert(scavenge_root_not_marked(), "");
  2210 #endif // PRODUCT
  2212 // Printing operations
  2214 void nmethod::print() const {
  2215   ResourceMark rm;
  2216   ttyLocker ttyl;   // keep the following output all in one block
  2218   tty->print("Compiled ");
  2220   if (is_compiled_by_c1()) {
  2221     tty->print("(c1) ");
  2222   } else if (is_compiled_by_c2()) {
  2223     tty->print("(c2) ");
  2224   } else {
  2225     tty->print("(nm) ");
  2228   print_on(tty, "nmethod");
  2229   tty->cr();
  2230   if (WizardMode) {
  2231     tty->print("((nmethod*) "INTPTR_FORMAT ") ", this);
  2232     tty->print(" for method " INTPTR_FORMAT , (address)method());
  2233     tty->print(" { ");
  2234     if (version())        tty->print("v%d ", version());
  2235     if (level())          tty->print("l%d ", level());
  2236     if (is_in_use())      tty->print("in_use ");
  2237     if (is_not_entrant()) tty->print("not_entrant ");
  2238     if (is_zombie())      tty->print("zombie ");
  2239     if (is_unloaded())    tty->print("unloaded ");
  2240     if (on_scavenge_root_list())  tty->print("scavenge_root ");
  2241     tty->print_cr("}:");
  2243   if (size              () > 0) tty->print_cr(" total in heap  [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
  2244                                               (address)this,
  2245                                               (address)this + size(),
  2246                                               size());
  2247   if (relocation_size   () > 0) tty->print_cr(" relocation     [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
  2248                                               relocation_begin(),
  2249                                               relocation_end(),
  2250                                               relocation_size());
  2251   if (code_size         () > 0) tty->print_cr(" main code      [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
  2252                                               code_begin(),
  2253                                               code_end(),
  2254                                               code_size());
  2255   if (stub_size         () > 0) tty->print_cr(" stub code      [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
  2256                                               stub_begin(),
  2257                                               stub_end(),
  2258                                               stub_size());
  2259   if (consts_size       () > 0) tty->print_cr(" constants      [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
  2260                                               consts_begin(),
  2261                                               consts_end(),
  2262                                               consts_size());
  2263   if (scopes_data_size  () > 0) tty->print_cr(" scopes data    [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
  2264                                               scopes_data_begin(),
  2265                                               scopes_data_end(),
  2266                                               scopes_data_size());
  2267   if (scopes_pcs_size   () > 0) tty->print_cr(" scopes pcs     [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
  2268                                               scopes_pcs_begin(),
  2269                                               scopes_pcs_end(),
  2270                                               scopes_pcs_size());
  2271   if (dependencies_size () > 0) tty->print_cr(" dependencies   [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
  2272                                               dependencies_begin(),
  2273                                               dependencies_end(),
  2274                                               dependencies_size());
  2275   if (handler_table_size() > 0) tty->print_cr(" handler table  [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
  2276                                               handler_table_begin(),
  2277                                               handler_table_end(),
  2278                                               handler_table_size());
  2279   if (nul_chk_table_size() > 0) tty->print_cr(" nul chk table  [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
  2280                                               nul_chk_table_begin(),
  2281                                               nul_chk_table_end(),
  2282                                               nul_chk_table_size());
  2283   if (oops_size         () > 0) tty->print_cr(" oops           [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
  2284                                               oops_begin(),
  2285                                               oops_end(),
  2286                                               oops_size());
  2289 void nmethod::print_code() {
  2290   HandleMark hm;
  2291   ResourceMark m;
  2292   Disassembler::decode(this);
  2296 #ifndef PRODUCT
  2298 void nmethod::print_scopes() {
  2299   // Find the first pc desc for all scopes in the code and print it.
  2300   ResourceMark rm;
  2301   for (PcDesc* p = scopes_pcs_begin(); p < scopes_pcs_end(); p++) {
  2302     if (p->scope_decode_offset() == DebugInformationRecorder::serialized_null)
  2303       continue;
  2305     ScopeDesc* sd = scope_desc_at(p->real_pc(this));
  2306     sd->print_on(tty, p);
  2310 void nmethod::print_dependencies() {
  2311   ResourceMark rm;
  2312   ttyLocker ttyl;   // keep the following output all in one block
  2313   tty->print_cr("Dependencies:");
  2314   for (Dependencies::DepStream deps(this); deps.next(); ) {
  2315     deps.print_dependency();
  2316     klassOop ctxk = deps.context_type();
  2317     if (ctxk != NULL) {
  2318       Klass* k = Klass::cast(ctxk);
  2319       if (k->oop_is_instance() && ((instanceKlass*)k)->is_dependent_nmethod(this)) {
  2320         tty->print_cr("   [nmethod<=klass]%s", k->external_name());
  2323     deps.log_dependency();  // put it into the xml log also
  2328 void nmethod::print_relocations() {
  2329   ResourceMark m;       // in case methods get printed via the debugger
  2330   tty->print_cr("relocations:");
  2331   RelocIterator iter(this);
  2332   iter.print();
  2333   if (UseRelocIndex) {
  2334     jint* index_end   = (jint*)relocation_end() - 1;
  2335     jint  index_size  = *index_end;
  2336     jint* index_start = (jint*)( (address)index_end - index_size );
  2337     tty->print_cr("    index @" INTPTR_FORMAT ": index_size=%d", index_start, index_size);
  2338     if (index_size > 0) {
  2339       jint* ip;
  2340       for (ip = index_start; ip+2 <= index_end; ip += 2)
  2341         tty->print_cr("  (%d %d) addr=" INTPTR_FORMAT " @" INTPTR_FORMAT,
  2342                       ip[0],
  2343                       ip[1],
  2344                       header_end()+ip[0],
  2345                       relocation_begin()-1+ip[1]);
  2346       for (; ip < index_end; ip++)
  2347         tty->print_cr("  (%d ?)", ip[0]);
  2348       tty->print_cr("          @" INTPTR_FORMAT ": index_size=%d", ip, *ip++);
  2349       tty->print_cr("reloc_end @" INTPTR_FORMAT ":", ip);
  2355 void nmethod::print_pcs() {
  2356   ResourceMark m;       // in case methods get printed via debugger
  2357   tty->print_cr("pc-bytecode offsets:");
  2358   for (PcDesc* p = scopes_pcs_begin(); p < scopes_pcs_end(); p++) {
  2359     p->print(this);
  2363 #endif // PRODUCT
  2365 const char* nmethod::reloc_string_for(u_char* begin, u_char* end) {
  2366   RelocIterator iter(this, begin, end);
  2367   bool have_one = false;
  2368   while (iter.next()) {
  2369     have_one = true;
  2370     switch (iter.type()) {
  2371         case relocInfo::none:                  return "no_reloc";
  2372         case relocInfo::oop_type: {
  2373           stringStream st;
  2374           oop_Relocation* r = iter.oop_reloc();
  2375           oop obj = r->oop_value();
  2376           st.print("oop(");
  2377           if (obj == NULL) st.print("NULL");
  2378           else obj->print_value_on(&st);
  2379           st.print(")");
  2380           return st.as_string();
  2382         case relocInfo::virtual_call_type:     return "virtual_call";
  2383         case relocInfo::opt_virtual_call_type: return "optimized virtual_call";
  2384         case relocInfo::static_call_type:      return "static_call";
  2385         case relocInfo::static_stub_type:      return "static_stub";
  2386         case relocInfo::runtime_call_type:     return "runtime_call";
  2387         case relocInfo::external_word_type:    return "external_word";
  2388         case relocInfo::internal_word_type:    return "internal_word";
  2389         case relocInfo::section_word_type:     return "section_word";
  2390         case relocInfo::poll_type:             return "poll";
  2391         case relocInfo::poll_return_type:      return "poll_return";
  2392         case relocInfo::type_mask:             return "type_bit_mask";
  2395   return have_one ? "other" : NULL;
  2398 // Return a the last scope in (begin..end]
  2399 ScopeDesc* nmethod::scope_desc_in(address begin, address end) {
  2400   PcDesc* p = pc_desc_near(begin+1);
  2401   if (p != NULL && p->real_pc(this) <= end) {
  2402     return new ScopeDesc(this, p->scope_decode_offset(),
  2403                          p->obj_decode_offset(), p->should_reexecute());
  2405   return NULL;
  2408 void nmethod::print_nmethod_labels(outputStream* stream, address block_begin) {
  2409   if (block_begin == entry_point())             stream->print_cr("[Entry Point]");
  2410   if (block_begin == verified_entry_point())    stream->print_cr("[Verified Entry Point]");
  2411   if (block_begin == exception_begin())         stream->print_cr("[Exception Handler]");
  2412   if (block_begin == stub_begin())              stream->print_cr("[Stub Code]");
  2413   if (block_begin == consts_begin())            stream->print_cr("[Constants]");
  2414   if (block_begin == entry_point()) {
  2415     methodHandle m = method();
  2416     if (m.not_null()) {
  2417       stream->print("  # ");
  2418       m->print_value_on(stream);
  2419       stream->cr();
  2421     if (m.not_null() && !is_osr_method()) {
  2422       ResourceMark rm;
  2423       int sizeargs = m->size_of_parameters();
  2424       BasicType* sig_bt = NEW_RESOURCE_ARRAY(BasicType, sizeargs);
  2425       VMRegPair* regs   = NEW_RESOURCE_ARRAY(VMRegPair, sizeargs);
  2427         int sig_index = 0;
  2428         if (!m->is_static())
  2429           sig_bt[sig_index++] = T_OBJECT; // 'this'
  2430         for (SignatureStream ss(m->signature()); !ss.at_return_type(); ss.next()) {
  2431           BasicType t = ss.type();
  2432           sig_bt[sig_index++] = t;
  2433           if (type2size[t] == 2) {
  2434             sig_bt[sig_index++] = T_VOID;
  2435           } else {
  2436             assert(type2size[t] == 1, "size is 1 or 2");
  2439         assert(sig_index == sizeargs, "");
  2441       const char* spname = "sp"; // make arch-specific?
  2442       intptr_t out_preserve = SharedRuntime::java_calling_convention(sig_bt, regs, sizeargs, false);
  2443       int stack_slot_offset = this->frame_size() * wordSize;
  2444       int tab1 = 14, tab2 = 24;
  2445       int sig_index = 0;
  2446       int arg_index = (m->is_static() ? 0 : -1);
  2447       bool did_old_sp = false;
  2448       for (SignatureStream ss(m->signature()); !ss.at_return_type(); ) {
  2449         bool at_this = (arg_index == -1);
  2450         bool at_old_sp = false;
  2451         BasicType t = (at_this ? T_OBJECT : ss.type());
  2452         assert(t == sig_bt[sig_index], "sigs in sync");
  2453         if (at_this)
  2454           stream->print("  # this: ");
  2455         else
  2456           stream->print("  # parm%d: ", arg_index);
  2457         stream->move_to(tab1);
  2458         VMReg fst = regs[sig_index].first();
  2459         VMReg snd = regs[sig_index].second();
  2460         if (fst->is_reg()) {
  2461           stream->print("%s", fst->name());
  2462           if (snd->is_valid())  {
  2463             stream->print(":%s", snd->name());
  2465         } else if (fst->is_stack()) {
  2466           int offset = fst->reg2stack() * VMRegImpl::stack_slot_size + stack_slot_offset;
  2467           if (offset == stack_slot_offset)  at_old_sp = true;
  2468           stream->print("[%s+0x%x]", spname, offset);
  2469         } else {
  2470           stream->print("reg%d:%d??", (int)(intptr_t)fst, (int)(intptr_t)snd);
  2472         stream->print(" ");
  2473         stream->move_to(tab2);
  2474         stream->print("= ");
  2475         if (at_this) {
  2476           m->method_holder()->print_value_on(stream);
  2477         } else {
  2478           bool did_name = false;
  2479           if (!at_this && ss.is_object()) {
  2480             symbolOop name = ss.as_symbol_or_null();
  2481             if (name != NULL) {
  2482               name->print_value_on(stream);
  2483               did_name = true;
  2486           if (!did_name)
  2487             stream->print("%s", type2name(t));
  2489         if (at_old_sp) {
  2490           stream->print("  (%s of caller)", spname);
  2491           did_old_sp = true;
  2493         stream->cr();
  2494         sig_index += type2size[t];
  2495         arg_index += 1;
  2496         if (!at_this)  ss.next();
  2498       if (!did_old_sp) {
  2499         stream->print("  # ");
  2500         stream->move_to(tab1);
  2501         stream->print("[%s+0x%x]", spname, stack_slot_offset);
  2502         stream->print("  (%s of caller)", spname);
  2503         stream->cr();
  2509 void nmethod::print_code_comment_on(outputStream* st, int column, u_char* begin, u_char* end) {
  2510   // First, find an oopmap in (begin, end].
  2511   // We use the odd half-closed interval so that oop maps and scope descs
  2512   // which are tied to the byte after a call are printed with the call itself.
  2513   address base = instructions_begin();
  2514   OopMapSet* oms = oop_maps();
  2515   if (oms != NULL) {
  2516     for (int i = 0, imax = oms->size(); i < imax; i++) {
  2517       OopMap* om = oms->at(i);
  2518       address pc = base + om->offset();
  2519       if (pc > begin) {
  2520         if (pc <= end) {
  2521           st->move_to(column);
  2522           st->print("; ");
  2523           om->print_on(st);
  2525         break;
  2530   // Print any debug info present at this pc.
  2531   ScopeDesc* sd  = scope_desc_in(begin, end);
  2532   if (sd != NULL) {
  2533     st->move_to(column);
  2534     if (sd->bci() == SynchronizationEntryBCI) {
  2535       st->print(";*synchronization entry");
  2536     } else {
  2537       if (sd->method().is_null()) {
  2538         st->print("method is NULL");
  2539       } else if (sd->method()->is_native()) {
  2540         st->print("method is native");
  2541       } else {
  2542         address bcp  = sd->method()->bcp_from(sd->bci());
  2543         Bytecodes::Code bc = Bytecodes::java_code_at(bcp);
  2544         st->print(";*%s", Bytecodes::name(bc));
  2545         switch (bc) {
  2546         case Bytecodes::_invokevirtual:
  2547         case Bytecodes::_invokespecial:
  2548         case Bytecodes::_invokestatic:
  2549         case Bytecodes::_invokeinterface:
  2551             Bytecode_invoke* invoke = Bytecode_invoke_at(sd->method(), sd->bci());
  2552             st->print(" ");
  2553             if (invoke->name() != NULL)
  2554               invoke->name()->print_symbol_on(st);
  2555             else
  2556               st->print("<UNKNOWN>");
  2557             break;
  2559         case Bytecodes::_getfield:
  2560         case Bytecodes::_putfield:
  2561         case Bytecodes::_getstatic:
  2562         case Bytecodes::_putstatic:
  2564             methodHandle sdm = sd->method();
  2565             Bytecode_field* field = Bytecode_field_at(sdm(), sdm->bcp_from(sd->bci()));
  2566             constantPoolOop sdmc = sdm->constants();
  2567             symbolOop name = sdmc->name_ref_at(field->index());
  2568             st->print(" ");
  2569             if (name != NULL)
  2570               name->print_symbol_on(st);
  2571             else
  2572               st->print("<UNKNOWN>");
  2578     // Print all scopes
  2579     for (;sd != NULL; sd = sd->sender()) {
  2580       st->move_to(column);
  2581       st->print("; -");
  2582       if (sd->method().is_null()) {
  2583         st->print("method is NULL");
  2584       } else {
  2585         sd->method()->print_short_name(st);
  2587       int lineno = sd->method()->line_number_from_bci(sd->bci());
  2588       if (lineno != -1) {
  2589         st->print("@%d (line %d)", sd->bci(), lineno);
  2590       } else {
  2591         st->print("@%d", sd->bci());
  2593       st->cr();
  2597   // Print relocation information
  2598   const char* str = reloc_string_for(begin, end);
  2599   if (str != NULL) {
  2600     if (sd != NULL) st->cr();
  2601     st->move_to(column);
  2602     st->print(";   {%s}", str);
  2604   int cont_offset = ImplicitExceptionTable(this).at(begin - instructions_begin());
  2605   if (cont_offset != 0) {
  2606     st->move_to(column);
  2607     st->print("; implicit exception: dispatches to " INTPTR_FORMAT, instructions_begin() + cont_offset);
  2612 #ifndef PRODUCT
  2614 void nmethod::print_value_on(outputStream* st) const {
  2615   print_on(st, "nmethod");
  2618 void nmethod::print_calls(outputStream* st) {
  2619   RelocIterator iter(this);
  2620   while (iter.next()) {
  2621     switch (iter.type()) {
  2622     case relocInfo::virtual_call_type:
  2623     case relocInfo::opt_virtual_call_type: {
  2624       VerifyMutexLocker mc(CompiledIC_lock);
  2625       CompiledIC_at(iter.reloc())->print();
  2626       break;
  2628     case relocInfo::static_call_type:
  2629       st->print_cr("Static call at " INTPTR_FORMAT, iter.reloc()->addr());
  2630       compiledStaticCall_at(iter.reloc())->print();
  2631       break;
  2636 void nmethod::print_handler_table() {
  2637   ExceptionHandlerTable(this).print();
  2640 void nmethod::print_nul_chk_table() {
  2641   ImplicitExceptionTable(this).print(instructions_begin());
  2644 void nmethod::print_statistics() {
  2645   ttyLocker ttyl;
  2646   if (xtty != NULL)  xtty->head("statistics type='nmethod'");
  2647   nmethod_stats.print_native_nmethod_stats();
  2648   nmethod_stats.print_nmethod_stats();
  2649   DebugInformationRecorder::print_statistics();
  2650   nmethod_stats.print_pc_stats();
  2651   Dependencies::print_statistics();
  2652   if (xtty != NULL)  xtty->tail("statistics");
  2655 #endif // PRODUCT

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