1 /*

     2  * Copyright 1998-2006 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  */

    24 

    25 #include "incls/_precompiled.incl"

    26 #include "incls/_bytecodeInfo.cpp.incl"

    27 

    28 // These variables are declared in parse1.cpp

    29 extern int  explicit_null_checks_inserted;

    30 extern int  explicit_null_checks_elided;

    31 extern int  explicit_null_checks_inserted_old;

    32 extern int  explicit_null_checks_elided_old;

    33 extern int  nodes_created_old;

    34 extern int  nodes_created;

    35 extern int  methods_parsed_old;

    36 extern int  methods_parsed;

    37 extern int  methods_seen;

    38 extern int  methods_seen_old;

    39 

    40 

    41 //=============================================================================

    42 //------------------------------InlineTree-------------------------------------

    43 InlineTree::InlineTree( Compile* c, const InlineTree *caller_tree, ciMethod* callee, JVMState* caller_jvms, int caller_bci, float site_invoke_ratio )

    44 : C(c), _caller_jvms(caller_jvms),

    45   _caller_tree((InlineTree*)caller_tree),

    46   _method(callee), _site_invoke_ratio(site_invoke_ratio),

    47   _count_inline_bcs(method()->code_size()) {

    48   NOT_PRODUCT(_count_inlines = 0;)

    49   if (_caller_jvms != NULL) {

    50     // Keep a private copy of the caller_jvms:

    51     _caller_jvms = new (C) JVMState(caller_jvms->method(), caller_tree->caller_jvms());

    52     _caller_jvms->set_bci(caller_jvms->bci());

    53   }

    54   assert(_caller_jvms->same_calls_as(caller_jvms), "consistent JVMS");

    55   assert((caller_tree == NULL ? 0 : caller_tree->inline_depth() + 1) == inline_depth(), "correct (redundant) depth parameter");

    56   assert(caller_bci == this->caller_bci(), "correct (redundant) bci parameter");

    57   if (UseOldInlining) {

    58     // Update hierarchical counts, count_inline_bcs() and count_inlines()

    59     InlineTree *caller = (InlineTree *)caller_tree;

    60     for( ; caller != NULL; caller = ((InlineTree *)(caller->caller_tree())) ) {

    61       caller->_count_inline_bcs += count_inline_bcs();

    62       NOT_PRODUCT(caller->_count_inlines++;)

    63     }

    64   }

    65 }

    66 

    67 InlineTree::InlineTree(Compile* c, ciMethod* callee_method, JVMState* caller_jvms, float site_invoke_ratio)

    68 : C(c), _caller_jvms(caller_jvms), _caller_tree(NULL),

    69   _method(callee_method), _site_invoke_ratio(site_invoke_ratio),

    70   _count_inline_bcs(method()->code_size()) {

    71   NOT_PRODUCT(_count_inlines = 0;)

    72   assert(!UseOldInlining, "do not use for old stuff");

    73 }

    74 

    75 

    76 

    77 static void print_indent(int depth) {

    78   tty->print("      ");

    79   for (int i = depth; i != 0; --i) tty->print("  ");

    80 }

    81 

    82 // positive filter: should send be inlined?  returns NULL, if yes, or rejection msg

    83 const char* InlineTree::shouldInline(ciMethod* callee_method, int caller_bci, ciCallProfile& profile, WarmCallInfo* wci_result) const {

    84   // Allows targeted inlining

    85   if(callee_method->should_inline()) {

    86     *wci_result = *(WarmCallInfo::always_hot());

    87     if (PrintInlining && Verbose) {

    88       print_indent(inline_depth());

    89       tty->print_cr("Inlined method is hot: ");

    90     }

    91     return NULL;

    92   }

    93 

    94   // positive filter: should send be inlined?  returns NULL (--> yes)

    95   // or rejection msg

    96   int max_size = C->max_inline_size();

    97   int size     = callee_method->code_size();

    98 

    99   // Check for too many throws (and not too huge)

   100   if(callee_method->interpreter_throwout_count() > InlineThrowCount && size < InlineThrowMaxSize ) {

   101     wci_result->set_profit(wci_result->profit() * 100);

   102     if (PrintInlining && Verbose) {

   103       print_indent(inline_depth());

   104       tty->print_cr("Inlined method with many throws (throws=%d):", callee_method->interpreter_throwout_count());

   105     }

   106     return NULL;

   107   }

   108 

   109   if (!UseOldInlining) {

   110     return NULL;  // size and frequency are represented in a new way

   111   }

   112 

   113   int call_site_count  = method()->scale_count(profile.count());

   114   int invoke_count     = method()->interpreter_invocation_count();

   115   assert( invoke_count != 0, "Require invokation count greater than zero");

   116   int freq = call_site_count/invoke_count;

   117   // bump the max size if the call is frequent

   118   if ((freq >= InlineFrequencyRatio) || (call_site_count >= InlineFrequencyCount)) {

   119     max_size = C->freq_inline_size();

   120     if (size <= max_size && TraceFrequencyInlining) {

   121       print_indent(inline_depth());

   122       tty->print_cr("Inlined frequent method (freq=%d count=%d):", freq, call_site_count);

   123       print_indent(inline_depth());

   124       callee_method->print();

   125       tty->cr();

   126     }

   127   } else {

   128     // Not hot.  Check for medium-sized pre-existing nmethod at cold sites.

   129     if (callee_method->has_compiled_code() && callee_method->instructions_size() > InlineSmallCode/4)

   130       return "already compiled into a medium method";

   131   }

   132   if (size > max_size) {

   133     if (max_size > C->max_inline_size())

   134       return "hot method too big";

   135     return "too big";

   136   }

   137   return NULL;

   138 }

   139 

   140 

   141 // negative filter: should send NOT be inlined?  returns NULL, ok to inline, or rejection msg

   142 const char* InlineTree::shouldNotInline(ciMethod *callee_method, WarmCallInfo* wci_result) const {

   143   // negative filter: should send NOT be inlined?  returns NULL (--> inline) or rejection msg

   144   if (!UseOldInlining) {

   145     const char* fail = NULL;

   146     if (callee_method->is_abstract())               fail = "abstract method";

   147     // note: we allow ik->is_abstract()

   148     if (!callee_method->holder()->is_initialized()) fail = "method holder not initialized";

   149     if (callee_method->is_native())                 fail = "native method";

   150 

   151     if (fail) {

   152       *wci_result = *(WarmCallInfo::always_cold());

   153       return fail;

   154     }

   155 

   156     if (callee_method->has_unloaded_classes_in_signature()) {

   157       wci_result->set_profit(wci_result->profit() * 0.1);

   158     }

   159 

   160     // don't inline exception code unless the top method belongs to an

   161     // exception class

   162     if (callee_method->holder()->is_subclass_of(C->env()->Throwable_klass())) {

   163       ciMethod* top_method = caller_jvms() ? caller_jvms()->of_depth(1)->method() : method();

   164       if (!top_method->holder()->is_subclass_of(C->env()->Throwable_klass())) {

   165         wci_result->set_profit(wci_result->profit() * 0.1);

   166       }

   167     }

   168 

   169     if (callee_method->has_compiled_code() && callee_method->instructions_size() > InlineSmallCode) {

   170       wci_result->set_profit(wci_result->profit() * 0.1);

   171       // %%% adjust wci_result->size()?

   172     }

   173 

   174     return NULL;

   175   }

   176 

   177   // First check all inlining restrictions which are required for correctness

   178   if (callee_method->is_abstract())               return "abstract method";

   179   // note: we allow ik->is_abstract()

   180   if (!callee_method->holder()->is_initialized()) return "method holder not initialized";

   181   if (callee_method->is_native())                 return "native method";

   182   if (callee_method->has_unloaded_classes_in_signature()) return "unloaded signature classes";

   183 

   184   if (callee_method->should_inline()) {

   185     // ignore heuristic controls on inlining

   186     return NULL;

   187   }

   188 

   189   // Now perform checks which are heuristic

   190 

   191   if( callee_method->has_compiled_code() && callee_method->instructions_size() > InlineSmallCode )

   192     return "already compiled into a big method";

   193 

   194   // don't inline exception code unless the top method belongs to an

   195   // exception class

   196   if (caller_tree() != NULL &&

   197       callee_method->holder()->is_subclass_of(C->env()->Throwable_klass())) {

   198     const InlineTree *top = this;

   199     while (top->caller_tree() != NULL) top = top->caller_tree();

   200     ciInstanceKlass* k = top->method()->holder();

   201     if (!k->is_subclass_of(C->env()->Throwable_klass()))

   202       return "exception method";

   203   }

   204 

   205   // use frequency-based objections only for non-trivial methods

   206   if (callee_method->code_size() <= MaxTrivialSize) return NULL;

   207   if (UseInterpreter && !CompileTheWorld) { // don't use counts with -Xcomp or CTW

   208     if (!callee_method->has_compiled_code() && !callee_method->was_executed_more_than(0)) return "never executed";

   209     if (!callee_method->was_executed_more_than(MIN2(MinInliningThreshold, CompileThreshold >> 1))) return "executed < MinInliningThreshold times";

   210   }

   211 

   212   if (callee_method->should_not_inline()) {

   213     return "disallowed by CompilerOracle";

   214   }

   215 

   216   return NULL;

   217 }

   218 

   219 //-----------------------------try_to_inline-----------------------------------

   220 // return NULL if ok, reason for not inlining otherwise

   221 // Relocated from "InliningClosure::try_to_inline"

   222 const char* InlineTree::try_to_inline(ciMethod* callee_method, int caller_bci, ciCallProfile& profile, WarmCallInfo* wci_result) {

   223   ciMethod* caller_method = method();

   224 

   225   // Old algorithm had funny accumulating BC-size counters

   226   if (UseOldInlining && ClipInlining

   227       && (int)count_inline_bcs() >= DesiredMethodLimit) {

   228     return "size > DesiredMethodLimit";

   229   }

   230 

   231   const char *msg = NULL;

   232   if ((msg = shouldInline(callee_method, caller_bci, profile, wci_result)) != NULL) return msg;

   233   if ((msg = shouldNotInline(callee_method,                   wci_result)) != NULL) return msg;

   234 

   235   bool is_accessor = InlineAccessors && callee_method->is_accessor();

   236 

   237   // suppress a few checks for accessors and trivial methods

   238   if (!is_accessor && callee_method->code_size() > MaxTrivialSize) {

   239     // don't inline into giant methods

   240     if (C->unique() > (uint)NodeCountInliningCutoff) return "NodeCountInliningCutoff";

   241 

   242     // don't inline unreached call sites

   243     if (profile.count() == 0)                        return "call site not reached";

   244   }

   245 

   246   if (!C->do_inlining() && InlineAccessors && !is_accessor) return "not an accessor";

   247 

   248   if( inline_depth() > MaxInlineLevel )           return "inlining too deep";

   249   if( method() == callee_method &&

   250       inline_depth() > MaxRecursiveInlineLevel )  return "recursively inlining too deep";

   251 

   252   int size = callee_method->code_size();

   253 

   254   if (UseOldInlining && ClipInlining

   255       && (int)count_inline_bcs() + size >= DesiredMethodLimit) {

   256     return "size > DesiredMethodLimit";

   257   }

   258 

   259   // ok, inline this method

   260   return NULL;

   261 }

   262 

   263 //------------------------------pass_initial_checks----------------------------

   264 bool pass_initial_checks(ciMethod* caller_method, int caller_bci, ciMethod* callee_method) {

   265   ciInstanceKlass *callee_holder = callee_method ? callee_method->holder() : NULL;

   266   // Check if a callee_method was suggested

   267   if( callee_method == NULL )            return false;

   268   // Check if klass of callee_method is loaded

   269   if( !callee_holder->is_loaded() )      return false;

   270   if( !callee_holder->is_initialized() ) return false;

   271   if( !UseInterpreter || CompileTheWorld /* running Xcomp or CTW */ ) {

   272     // Checks that constant pool's call site has been visited

   273     // stricter than callee_holder->is_initialized()

   274     ciBytecodeStream iter(caller_method);

   275     iter.force_bci(caller_bci);

   276     int index = iter.get_index_big();

   277     if( !caller_method->is_klass_loaded(index, true) ) {

   278       return false;

   279     }

   280     // Try to do constant pool resolution if running Xcomp

   281     Bytecodes::Code call_bc = iter.cur_bc();

   282     if( !caller_method->check_call(index, call_bc == Bytecodes::_invokestatic) ) {

   283       return false;

   284     }

   285   }

   286   // We will attempt to see if a class/field/etc got properly loaded.  If it

   287   // did not, it may attempt to throw an exception during our probing.  Catch

   288   // and ignore such exceptions and do not attempt to compile the method.

   289   if( callee_method->should_exclude() )  return false;

   290 

   291   return true;

   292 }

   293 

   294 #ifndef PRODUCT

   295 //------------------------------print_inlining---------------------------------

   296 // Really, the failure_msg can be a success message also.

   297 void InlineTree::print_inlining(ciMethod *callee_method, int caller_bci, const char *failure_msg) const {

   298   print_indent(inline_depth());

   299   tty->print("@ %d  ", caller_bci);

   300   if( callee_method ) callee_method->print_short_name();

   301   else                tty->print(" callee not monotonic or profiled");

   302   tty->print("  %s", (failure_msg ? failure_msg : "inline"));

   303   if( Verbose && callee_method ) {

   304     const InlineTree *top = this;

   305     while( top->caller_tree() != NULL ) { top = top->caller_tree(); }

   306     tty->print("  bcs: %d+%d  invoked: %d", top->count_inline_bcs(), callee_method->code_size(), callee_method->interpreter_invocation_count());

   307   }

   308   tty->cr();

   309 }

   310 #endif

   311 

   312 //------------------------------ok_to_inline-----------------------------------

   313 WarmCallInfo* InlineTree::ok_to_inline(ciMethod* callee_method, JVMState* jvms, ciCallProfile& profile, WarmCallInfo* initial_wci) {

   314   assert(callee_method != NULL, "caller checks for optimized virtual!");

   315 #ifdef ASSERT

   316   // Make sure the incoming jvms has the same information content as me.

   317   // This means that we can eventually make this whole class AllStatic.

   318   if (jvms->caller() == NULL) {

   319     assert(_caller_jvms == NULL, "redundant instance state");

   320   } else {

   321     assert(_caller_jvms->same_calls_as(jvms->caller()), "redundant instance state");

   322   }

   323   assert(_method == jvms->method(), "redundant instance state");

   324 #endif

   325   const char *failure_msg   = NULL;

   326   int         caller_bci    = jvms->bci();

   327   ciMethod   *caller_method = jvms->method();

   328 

   329   if( !pass_initial_checks(caller_method, caller_bci, callee_method)) {

   330     if( PrintInlining ) {

   331       failure_msg = "failed_initial_checks";

   332       print_inlining( callee_method, caller_bci, failure_msg);

   333     }

   334     return NULL;

   335   }

   336 

   337   // Check if inlining policy says no.

   338   WarmCallInfo wci = *(initial_wci);

   339   failure_msg = try_to_inline(callee_method, caller_bci, profile, &wci);

   340   if (failure_msg != NULL && C->log() != NULL) {

   341     C->log()->begin_elem("inline_fail reason='");

   342     C->log()->text("%s", failure_msg);

   343     C->log()->end_elem("'");

   344   }

   345 

   346 #ifndef PRODUCT

   347   if (UseOldInlining && InlineWarmCalls

   348       && (PrintOpto || PrintOptoInlining || PrintInlining)) {

   349     bool cold = wci.is_cold();

   350     bool hot  = !cold && wci.is_hot();

   351     bool old_cold = (failure_msg != NULL);

   352     if (old_cold != cold || (Verbose || WizardMode)) {

   353       tty->print("   OldInlining= %4s : %s\n           WCI=",

   354                  old_cold ? "cold" : "hot", failure_msg ? failure_msg : "OK");

   355       wci.print();

   356     }

   357   }

   358 #endif

   359   if (UseOldInlining) {

   360     if (failure_msg == NULL)

   361       wci = *(WarmCallInfo::always_hot());

   362     else

   363       wci = *(WarmCallInfo::always_cold());

   364   }

   365   if (!InlineWarmCalls) {

   366     if (!wci.is_cold() && !wci.is_hot()) {

   367       // Do not inline the warm calls.

   368       wci = *(WarmCallInfo::always_cold());

   369     }

   370   }

   371 

   372   if (!wci.is_cold()) {

   373     // In -UseOldInlining, the failure_msg may also be a success message.

   374     if (failure_msg == NULL)  failure_msg = "inline (hot)";

   375 

   376     // Inline!

   377     if( PrintInlining ) print_inlining( callee_method, caller_bci, failure_msg);

   378     if (UseOldInlining)

   379       build_inline_tree_for_callee(callee_method, jvms, caller_bci);

   380     if (InlineWarmCalls && !wci.is_hot())

   381       return new (C) WarmCallInfo(wci);  // copy to heap

   382     return WarmCallInfo::always_hot();

   383   }

   384 

   385   // Do not inline

   386   if (failure_msg == NULL)  failure_msg = "too cold to inline";

   387   if( PrintInlining ) print_inlining( callee_method, caller_bci, failure_msg);

   388   return NULL;

   389 }

   390 

   391 //------------------------------compute_callee_frequency-----------------------

   392 float InlineTree::compute_callee_frequency( int caller_bci ) const {

   393   int count  = method()->interpreter_call_site_count(caller_bci);

   394   int invcnt = method()->interpreter_invocation_count();

   395   float freq = (float)count/(float)invcnt;

   396   // Call-site count / interpreter invocation count, scaled recursively.

   397   // Always between 0.0 and 1.0.  Represents the percentage of the method's

   398   // total execution time used at this call site.

   399 

   400   return freq;

   401 }

   402 

   403 //------------------------------build_inline_tree_for_callee-------------------

   404 InlineTree *InlineTree::build_inline_tree_for_callee( ciMethod* callee_method, JVMState* caller_jvms, int caller_bci) {

   405   float recur_frequency = _site_invoke_ratio * compute_callee_frequency(caller_bci);

   406   // Attempt inlining.

   407   InlineTree* old_ilt = callee_at(caller_bci, callee_method);

   408   if (old_ilt != NULL) {

   409     return old_ilt;

   410   }

   411   InlineTree *ilt = new InlineTree( C, this, callee_method, caller_jvms, caller_bci, recur_frequency );

   412   _subtrees.append( ilt );

   413 

   414   NOT_PRODUCT( _count_inlines += 1; )

   415 

   416   return ilt;

   417 }

   418 

   419 

   420 //---------------------------------------callee_at-----------------------------

   421 InlineTree *InlineTree::callee_at(int bci, ciMethod* callee) const {

   422   for (int i = 0; i < _subtrees.length(); i++) {

   423     InlineTree* sub = _subtrees.at(i);

   424     if (sub->caller_bci() == bci && callee == sub->method()) {

   425       return sub;

   426     }

   427   }

   428   return NULL;

   429 }

   430 

   431 

   432 //------------------------------build_inline_tree_root-------------------------

   433 InlineTree *InlineTree::build_inline_tree_root() {

   434   Compile* C = Compile::current();

   435 

   436   // Root of inline tree

   437   InlineTree *ilt = new InlineTree(C, NULL, C->method(), NULL, -1, 1.0F);

   438 

   439   return ilt;

   440 }

   441 

   442 

   443 //-------------------------find_subtree_from_root-----------------------------

   444 // Given a jvms, which determines a call chain from the root method,

   445 // find the corresponding inline tree.

   446 // Note: This method will be removed or replaced as InlineTree goes away.

   447 InlineTree* InlineTree::find_subtree_from_root(InlineTree* root, JVMState* jvms, ciMethod* callee, bool create_if_not_found) {

   448   InlineTree* iltp = root;

   449   uint depth = jvms && jvms->has_method() ? jvms->depth() : 0;

   450   for (uint d = 1; d <= depth; d++) {

   451     JVMState* jvmsp  = jvms->of_depth(d);

   452     // Select the corresponding subtree for this bci.

   453     assert(jvmsp->method() == iltp->method(), "tree still in sync");

   454     ciMethod* d_callee = (d == depth) ? callee : jvms->of_depth(d+1)->method();

   455     InlineTree* sub = iltp->callee_at(jvmsp->bci(), d_callee);

   456     if (!sub) {

   457       if (create_if_not_found && d == depth) {

   458         return iltp->build_inline_tree_for_callee(d_callee, jvmsp, jvmsp->bci());

   459       }

   460       assert(sub != NULL, "should be a sub-ilt here");

   461       return NULL;

   462     }

   463     iltp = sub;

   464   }

   465   return iltp;

   466 }

   467 

   468 // ----------------------------------------------------------------------------

   469 #ifndef PRODUCT

   470 

   471 static void per_method_stats() {

   472   // Compute difference between this method's cumulative totals and old totals

   473   int explicit_null_checks_cur = explicit_null_checks_inserted - explicit_null_checks_inserted_old;

   474   int elided_null_checks_cur = explicit_null_checks_elided - explicit_null_checks_elided_old;

   475 

   476   // Print differences

   477   if( explicit_null_checks_cur )

   478     tty->print_cr("XXX Explicit NULL checks inserted: %d", explicit_null_checks_cur);

   479   if( elided_null_checks_cur )

   480     tty->print_cr("XXX Explicit NULL checks removed at parse time: %d", elided_null_checks_cur);

   481 

   482   // Store the current cumulative totals

   483   nodes_created_old = nodes_created;

   484   methods_parsed_old = methods_parsed;

   485   methods_seen_old = methods_seen;

   486   explicit_null_checks_inserted_old = explicit_null_checks_inserted;

   487   explicit_null_checks_elided_old = explicit_null_checks_elided;

   488 }

   489 

   490 #endif