Mercurial > jdk8-mips64-public > hotspot / file revision

 /*

  * Copyright 2000-2010 Sun Microsystems, Inc.  All Rights Reserved.

  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.

  *

  * This code is free software; you can redistribute it and/or modify it

  * under the terms of the GNU General Public License version 2 only, as

  * published by the Free Software Foundation.

  *

  * This code is distributed in the hope that it will be useful, but WITHOUT

  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or

  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License

  * version 2 for more details (a copy is included in the LICENSE file that

  * accompanied this code).

  *

  * You should have received a copy of the GNU General Public License version

  * 2 along with this work; if not, write to the Free Software Foundation,

  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.

  *

  * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,

  * CA 95054 USA or visit www.sun.com if you need additional information or

  * have any questions.

  *

  */

 # include "incls/_precompiled.incl"

 # include "incls/_compilationPolicy.cpp.incl"

 CompilationPolicy* CompilationPolicy::_policy;

 elapsedTimer       CompilationPolicy::_accumulated_time;

 bool               CompilationPolicy::_in_vm_startup;

 // Determine compilation policy based on command line argument

 void compilationPolicy_init() {

   CompilationPolicy::set_in_vm_startup(DelayCompilationDuringStartup);

   switch(CompilationPolicyChoice) {

   case 0:

     CompilationPolicy::set_policy(new SimpleCompPolicy());

     break;

   case 1:

 #ifdef COMPILER2

     CompilationPolicy::set_policy(new StackWalkCompPolicy());

 #else

     Unimplemented();

 #endif

     break;

   default:

     fatal("CompilationPolicyChoice must be in the range: [0-1]");

   }

 }

 void CompilationPolicy::completed_vm_startup() {

   if (TraceCompilationPolicy) {

     tty->print("CompilationPolicy: completed vm startup.\n");

   }

   _in_vm_startup = false;

 }

 // Returns true if m must be compiled before executing it

 // This is intended to force compiles for methods (usually for

 // debugging) that would otherwise be interpreted for some reason.

 bool CompilationPolicy::mustBeCompiled(methodHandle m) {

   if (m->has_compiled_code()) return false;       // already compiled

   if (!canBeCompiled(m))      return false;

   return !UseInterpreter ||                                              // must compile all methods

          (UseCompiler && AlwaysCompileLoopMethods && m->has_loops()); // eagerly compile loop methods

 }

 // Returns true if m is allowed to be compiled

 bool CompilationPolicy::canBeCompiled(methodHandle m) {

   if (m->is_abstract()) return false;

   if (DontCompileHugeMethods && m->code_size() > HugeMethodLimit) return false;

   // Math intrinsics should never be compiled as this can lead to

   // monotonicity problems because the interpreter will prefer the

   // compiled code to the intrinsic version.  This can't happen in

   // production because the invocation counter can't be incremented

   // but we shouldn't expose the system to this problem in testing

   // modes.

   if (!AbstractInterpreter::can_be_compiled(m)) {

     return false;

   }

   return !m->is_not_compilable();

 }

 #ifndef PRODUCT

 void CompilationPolicy::print_time() {

   tty->print_cr ("Accumulated compilationPolicy times:");

   tty->print_cr ("---------------------------");

   tty->print_cr ("  Total: %3.3f sec.", _accumulated_time.seconds());

 }

 static void trace_osr_completion(nmethod* osr_nm) {

   if (TraceOnStackReplacement) {

     if (osr_nm == NULL) tty->print_cr("compilation failed");

     else tty->print_cr("nmethod " INTPTR_FORMAT, osr_nm);

   }

 }

 #endif // !PRODUCT

 void CompilationPolicy::reset_counter_for_invocation_event(methodHandle m) {

   // Make sure invocation and backedge counter doesn't overflow again right away

   // as would be the case for native methods.

   // BUT also make sure the method doesn't look like it was never executed.

   // Set carry bit and reduce counter's value to min(count, CompileThreshold/2).

   m->invocation_counter()->set_carry();

   m->backedge_counter()->set_carry();

   assert(!m->was_never_executed(), "don't reset to 0 -- could be mistaken for never-executed");

 }

 void CompilationPolicy::reset_counter_for_back_branch_event(methodHandle m) {

   // Delay next back-branch event but pump up invocation counter to triger

   // whole method compilation.

   InvocationCounter* i = m->invocation_counter();

   InvocationCounter* b = m->backedge_counter();

   // Don't set invocation_counter's value too low otherwise the method will

   // look like immature (ic < ~5300) which prevents the inlining based on

   // the type profiling.

   i->set(i->state(), CompileThreshold);

   // Don't reset counter too low - it is used to check if OSR method is ready.

   b->set(b->state(), CompileThreshold / 2);

 }

 // SimpleCompPolicy - compile current method

 void SimpleCompPolicy::method_invocation_event( methodHandle m, TRAPS) {

   assert(UseCompiler || CompileTheWorld, "UseCompiler should be set by now.");

   int hot_count = m->invocation_count();

   reset_counter_for_invocation_event(m);

   const char* comment = "count";

   if (!delayCompilationDuringStartup() && canBeCompiled(m) && UseCompiler) {

     nmethod* nm = m->code();

     if (nm == NULL ) {

       const char* comment = "count";

       CompileBroker::compile_method(m, InvocationEntryBci,

                                     m, hot_count, comment, CHECK);

     } else {

 #ifdef TIERED

       if (nm->is_compiled_by_c1()) {

         const char* comment = "tier1 overflow";

         CompileBroker::compile_method(m, InvocationEntryBci,

                                       m, hot_count, comment, CHECK);

       }

 #endif // TIERED

     }

   }

 }

 void SimpleCompPolicy::method_back_branch_event(methodHandle m, int branch_bci, int loop_top_bci, TRAPS) {

   assert(UseCompiler || CompileTheWorld, "UseCompiler should be set by now.");

   int hot_count = m->backedge_count();

   const char* comment = "backedge_count";

   if (!m->is_not_osr_compilable() && !delayCompilationDuringStartup() && canBeCompiled(m)) {

     CompileBroker::compile_method(m, loop_top_bci, m, hot_count, comment, CHECK);

     NOT_PRODUCT(trace_osr_completion(m->lookup_osr_nmethod_for(loop_top_bci));)

   }

 }

 int SimpleCompPolicy::compilation_level(methodHandle m, int branch_bci)

 {

 #ifdef TIERED

   if (!TieredCompilation) {

     return CompLevel_highest_tier;

   }

   if (/* m()->tier1_compile_done() && */

      // QQQ HACK FIX ME set tier1_compile_done!!

       !m()->is_native()) {

     // Grab the nmethod so it doesn't go away while it's being queried

     nmethod* code = m()->code();

     if (code != NULL && code->is_compiled_by_c1()) {

       return CompLevel_highest_tier;

     }

   }

   return CompLevel_fast_compile;

 #else

   return CompLevel_highest_tier;

 #endif // TIERED

 }

 // StackWalkCompPolicy - walk up stack to find a suitable method to compile

 #ifdef COMPILER2

 const char* StackWalkCompPolicy::_msg = NULL;

 // Consider m for compilation

 void StackWalkCompPolicy::method_invocation_event(methodHandle m, TRAPS) {

   assert(UseCompiler || CompileTheWorld, "UseCompiler should be set by now.");

   int hot_count = m->invocation_count();

   reset_counter_for_invocation_event(m);

   const char* comment = "count";

   if (m->code() == NULL && !delayCompilationDuringStartup() && canBeCompiled(m) && UseCompiler) {

     ResourceMark rm(THREAD);

     JavaThread *thread = (JavaThread*)THREAD;

     frame       fr     = thread->last_frame();

     assert(fr.is_interpreted_frame(), "must be interpreted");

     assert(fr.interpreter_frame_method() == m(), "bad method");

     if (TraceCompilationPolicy) {

       tty->print("method invocation trigger: ");

       m->print_short_name(tty);

       tty->print(" ( interpreted " INTPTR_FORMAT ", size=%d ) ", (address)m(), m->code_size());

     }

     RegisterMap reg_map(thread, false);

     javaVFrame* triggerVF = thread->last_java_vframe(&reg_map);

     // triggerVF is the frame that triggered its counter

     RFrame* first = new InterpretedRFrame(triggerVF->fr(), thread, m);

     if (first->top_method()->code() != NULL) {

       // called obsolete method/nmethod -- no need to recompile

       if (TraceCompilationPolicy) tty->print_cr(" --> " INTPTR_FORMAT, first->top_method()->code());

     } else if (compilation_level(m, InvocationEntryBci) == CompLevel_fast_compile) {

       // Tier1 compilation policy avaoids stack walking.

       CompileBroker::compile_method(m, InvocationEntryBci,

                                     m, hot_count, comment, CHECK);

     } else {

       if (TimeCompilationPolicy) accumulated_time()->start();

       GrowableArray<RFrame*>* stack = new GrowableArray<RFrame*>(50);

       stack->push(first);

       RFrame* top = findTopInlinableFrame(stack);

       if (TimeCompilationPolicy) accumulated_time()->stop();

       assert(top != NULL, "findTopInlinableFrame returned null");

       if (TraceCompilationPolicy) top->print();

       CompileBroker::compile_method(top->top_method(), InvocationEntryBci,

                                     m, hot_count, comment, CHECK);

     }

   }

 }

 void StackWalkCompPolicy::method_back_branch_event(methodHandle m, int branch_bci, int loop_top_bci, TRAPS) {

   assert(UseCompiler || CompileTheWorld, "UseCompiler should be set by now.");

   int hot_count = m->backedge_count();

   const char* comment = "backedge_count";

   if (!m->is_not_osr_compilable() && !delayCompilationDuringStartup() && canBeCompiled(m)) {

     CompileBroker::compile_method(m, loop_top_bci, m, hot_count, comment, CHECK);

     NOT_PRODUCT(trace_osr_completion(m->lookup_osr_nmethod_for(loop_top_bci));)

   }

 }

 int StackWalkCompPolicy::compilation_level(methodHandle m, int osr_bci)

 {

   int comp_level = CompLevel_full_optimization;

   if (TieredCompilation && osr_bci == InvocationEntryBci) {

     if (CompileTheWorld) {

       // Under CTW, the first compile is tier1, the second tier2

       if (m->highest_tier_compile() == CompLevel_none) {

         comp_level = CompLevel_fast_compile;

       }

     } else if (!m->has_osr_nmethod()) {

       // Before tier1 is done, use invocation_count + backedge_count to

       // compare against the threshold.  After that, the counters may/will

       // be reset, so rely on the straight interpreter_invocation_count.

       if (m->highest_tier_compile() == CompLevel_initial_compile) {

         if (m->interpreter_invocation_count() < Tier2CompileThreshold) {

           comp_level = CompLevel_fast_compile;

         }

       } else if (m->invocation_count() + m->backedge_count() <

                  Tier2CompileThreshold) {

         comp_level = CompLevel_fast_compile;

       }

     }

   }

   return comp_level;

 }

 RFrame* StackWalkCompPolicy::findTopInlinableFrame(GrowableArray<RFrame*>* stack) {

   // go up the stack until finding a frame that (probably) won't be inlined

   // into its caller

   RFrame* current = stack->at(0); // current choice for stopping

   assert( current && !current->is_compiled(), "" );

   const char* msg = NULL;

   while (1) {

     // before going up the stack further, check if doing so would get us into

     // compiled code

     RFrame* next = senderOf(current, stack);

     if( !next )               // No next frame up the stack?

       break;                  // Then compile with current frame

     methodHandle m = current->top_method();

     methodHandle next_m = next->top_method();

     if (TraceCompilationPolicy && Verbose) {

       tty->print("[caller: ");

       next_m->print_short_name(tty);

       tty->print("] ");

     }

     if( !Inline ) {           // Inlining turned off

       msg = "Inlining turned off";

       break;

     }

     if (next_m->is_not_compilable()) { // Did fail to compile this before/

       msg = "caller not compilable";

       break;

     }

     if (next->num() > MaxRecompilationSearchLength) {

       // don't go up too high when searching for recompilees

       msg = "don't go up any further: > MaxRecompilationSearchLength";

       break;

     }

     if (next->distance() > MaxInterpretedSearchLength) {

       // don't go up too high when searching for recompilees

       msg = "don't go up any further: next > MaxInterpretedSearchLength";

       break;

     }

     // Compiled frame above already decided not to inline;

     // do not recompile him.

     if (next->is_compiled()) {

       msg = "not going up into optimized code";

       break;

     }

     // Interpreted frame above us was already compiled.  Do not force

     // a recompile, although if the frame above us runs long enough an

     // OSR might still happen.

     if( current->is_interpreted() && next_m->has_compiled_code() ) {

       msg = "not going up -- already compiled caller";

       break;

     }

     // Compute how frequent this call site is.  We have current method 'm'.

     // We know next method 'next_m' is interpreted.  Find the call site and

     // check the various invocation counts.

     int invcnt = 0;             // Caller counts

     if (ProfileInterpreter) {

       invcnt = next_m->interpreter_invocation_count();

     }

     int cnt = 0;                // Call site counts

     if (ProfileInterpreter && next_m->method_data() != NULL) {

       ResourceMark rm;

       int bci = next->top_vframe()->bci();

       ProfileData* data = next_m->method_data()->bci_to_data(bci);

       if (data != NULL && data->is_CounterData())

         cnt = data->as_CounterData()->count();

     }

     // Caller counts / call-site counts; i.e. is this call site

     // a hot call site for method next_m?

     int freq = (invcnt) ? cnt/invcnt : cnt;

     // Check size and frequency limits

     if ((msg = shouldInline(m, freq, cnt)) != NULL) {

       break;

     }

     // Check inlining negative tests

     if ((msg = shouldNotInline(m)) != NULL) {

       break;

     }

     // If the caller method is too big or something then we do not want to

     // compile it just to inline a method

     if (!canBeCompiled(next_m)) {

       msg = "caller cannot be compiled";

       break;

     }

     if( next_m->name() == vmSymbols::class_initializer_name() ) {

       msg = "do not compile class initializer (OSR ok)";

       break;

     }

     if (TraceCompilationPolicy && Verbose) {

       tty->print("\n\t     check caller: ");

       next_m->print_short_name(tty);

       tty->print(" ( interpreted " INTPTR_FORMAT ", size=%d ) ", (address)next_m(), next_m->code_size());

     }

     current = next;

   }

   assert( !current || !current->is_compiled(), "" );

   if (TraceCompilationPolicy && msg) tty->print("(%s)\n", msg);

   return current;

 }

 RFrame* StackWalkCompPolicy::senderOf(RFrame* rf, GrowableArray<RFrame*>* stack) {

   RFrame* sender = rf->caller();

   if (sender && sender->num() == stack->length()) stack->push(sender);

   return sender;

 }

 const char* StackWalkCompPolicy::shouldInline(methodHandle m, float freq, int cnt) {

   // Allows targeted inlining

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

   // or rejection msg

   int max_size = MaxInlineSize;

   int cost = m->code_size();

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

   if (m->interpreter_throwout_count() > InlineThrowCount && cost < InlineThrowMaxSize ) {

     return NULL;

   }

   // bump the max size if the call is frequent

   if ((freq >= InlineFrequencyRatio) || (cnt >= InlineFrequencyCount)) {

     if (TraceFrequencyInlining) {

       tty->print("(Inlined frequent method)\n");

       m->print();

     }

     max_size = FreqInlineSize;

   }

   if (cost > max_size) {

     return (_msg = "too big");

   }

   return NULL;

 }

 const char* StackWalkCompPolicy::shouldNotInline(methodHandle m) {

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

   if (m->is_abstract()) return (_msg = "abstract method");

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

   if (!instanceKlass::cast(m->method_holder())->is_initialized()) return (_msg = "method holder not initialized");

   if (m->is_native()) return (_msg = "native method");

   nmethod* m_code = m->code();

   if( m_code != NULL && m_code->instructions_size() > InlineSmallCode )

     return (_msg = "already compiled into a big method");

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

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

   if (UseInterpreter) {     // don't use counts with -Xcomp

     if ((m->code() == NULL) && m->was_never_executed()) return (_msg = "never executed");

     if (!m->was_executed_more_than(MIN2(MinInliningThreshold, CompileThreshold >> 1))) return (_msg = "executed < MinInliningThreshold times");

   }

   if (methodOopDesc::has_unloaded_classes_in_signature(m, JavaThread::current())) return (_msg = "unloaded signature classes");

   return NULL;

 }

 #endif // COMPILER2