Move static flag modifications to V8::InitializeOncePerProcessImpl().

src/v8.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 253 matching lines @@
 }
 
 void V8::InitializeOncePerProcessImpl() {
   FlagList::EnforceFlagImplications();
   if (FLAG_stress_compaction) {
     FLAG_force_marking_deque_overflows = true;
     FLAG_gc_global = true;
     FLAG_max_new_space_size = (1 << (kPageSizeBits - 10)) * 2;
   }
   if (FLAG_trace_hydrogen) FLAG_parallel_recompilation = false;
+
+  if (FLAG_sweeper_threads <= 0) {
+    if (FLAG_concurrent_sweeping) {
+      FLAG_sweeper_threads = SystemThreadManager::
+          NumberOfParallelSystemThreads(
+              SystemThreadManager::CONCURRENT_SWEEPING);
+    } else if (FLAG_parallel_sweeping) {
+      FLAG_sweeper_threads = SystemThreadManager::
+          NumberOfParallelSystemThreads(
+              SystemThreadManager::PARALLEL_SWEEPING);
+    }
+    if (FLAG_sweeper_threads == 0) {
+      FLAG_concurrent_sweeping = false;
+      FLAG_parallel_sweeping = false;
+    }
+  } else if (!FLAG_concurrent_sweeping && !FLAG_parallel_sweeping) {
+    FLAG_sweeper_threads = 0;
+  }
+
+  if (FLAG_parallel_marking) {
+    if (FLAG_marking_threads <= 0) {
+      FLAG_marking_threads = SystemThreadManager::
+          NumberOfParallelSystemThreads(
+              SystemThreadManager::PARALLEL_MARKING);
+    }
+    if (FLAG_marking_threads == 0) {
+      FLAG_parallel_marking = false;
+    }
+  } else {
+    FLAG_marking_threads = 0;
+  }
+
+  if (FLAG_parallel_recompilation &&
+      SystemThreadManager::NumberOfParallelSystemThreads(
+          SystemThreadManager::PARALLEL_RECOMPILATION) == 0) {
+    FLAG_parallel_recompilation = false;
+  }
+
   OS::SetUp();
   Sampler::SetUp();
   CPU::SetUp();
   use_crankshaft_ = FLAG_crankshaft
       && !Serializer::enabled()
       && CPU::SupportsCrankshaft();
   OS::PostSetUp();
   ElementsAccessor::InitializeOncePerProcess();
   LOperand::SetUpCaches();
   SetUpJSCallerSavedCodeData();
   ExternalReference::SetUp();
   Bootstrapper::InitializeOncePerProcess();
 }
 
 void V8::InitializeOncePerProcess() {
   CallOnce(&init_once, &InitializeOncePerProcessImpl);
 }
 
 } }  // namespace v8::internal