Details wrt parallel recompilation.

src/isolate.cc

 // Copyright 2012 the V8 project authors. All rights reserved.
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
 //
 //     * Redistributions of source code must retain the above copyright
 //       notice, this list of conditions and the following disclaimer.
 //     * Redistributions in binary form must reproduce the above
 //       copyright notice, this list of conditions and the following
 //       disclaimer in the documentation and/or other materials provided
@@ skipping 1754 matching lines @@
 
 void Isolate::GlobalTearDown() {
   delete thread_data_table_;
 }
 
 
 void Isolate::Deinit() {
   if (state_ == INITIALIZED) {
     TRACE_ISOLATE(deinit);
 
+    if (FLAG_parallel_recompilation) optimizing_compiler_thread_.Stop();
+
     if (FLAG_sweeper_threads > 0) {
       for (int i = 0; i < FLAG_sweeper_threads; i++) {
         sweeper_thread_[i]->Stop();
         delete sweeper_thread_[i];
       }
       delete[] sweeper_thread_;
     }
 
     if (FLAG_marking_threads > 0) {
       for (int i = 0; i < FLAG_marking_threads; i++) {
         marking_thread_[i]->Stop();
         delete marking_thread_[i];
       }
       delete[] marking_thread_;
     }
 
-    if (FLAG_parallel_recompilation) optimizing_compiler_thread_.Stop();
-
     if (FLAG_hydrogen_stats) HStatistics::Instance()->Print();
 
     // We must stop the logger before we tear down other components.
     logger_->EnsureTickerStopped();
 
     delete deoptimizer_data_;
     deoptimizer_data_ = NULL;
     if (FLAG_preemption) {
       v8::Locker locker(reinterpret_cast<v8::Isolate*>(this));
       v8::Locker::StopPreemption();
@@ skipping 388 matching lines @@
   if (FLAG_sweeper_threads > 0) {
     sweeper_thread_ = new SweeperThread*[FLAG_sweeper_threads];
     for (int i = 0; i < FLAG_sweeper_threads; i++) {
       sweeper_thread_[i] = new SweeperThread(this);
       sweeper_thread_[i]->Start();
     }
   } else {
     FLAG_concurrent_sweeping = false;
     FLAG_parallel_sweeping = false;
   }
+  if (FLAG_parallel_recompilation &&
+      SystemThreadManager::NumberOfParallelSystemThreads(
+          SystemThreadManager::PARALLEL_RECOMPILATION) == 0) {
+    FLAG_parallel_recompilation = false;
+  }
   return true;
 }
 
 
 // Initialized lazily to allow early
 // v8::V8::SetAddHistogramSampleFunction calls.
 StatsTable* Isolate::stats_table() {
   if (stats_table_ == NULL) {
     stats_table_ = new StatsTable;
   }
@@ skipping 108 matching lines @@
 
 #ifdef DEBUG
 #define ISOLATE_FIELD_OFFSET(type, name, ignored)                       \
 const intptr_t Isolate::name##_debug_offset_ = OFFSET_OF(Isolate, name##_);
 ISOLATE_INIT_LIST(ISOLATE_FIELD_OFFSET)
 ISOLATE_INIT_ARRAY_LIST(ISOLATE_FIELD_OFFSET)
 #undef ISOLATE_FIELD_OFFSET
 #endif
 
 } }  // namespace v8::internal