Less aggressive polling when concurrently compiling for OSR.

src/runtime.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 8590 matching lines @@
   ASSERT(pc_offset ==
          static_cast<uint32_t>(frame->pc() - unoptimized->instruction_start()));
 #endif  // DEBUG
 
   // We're not prepared to handle a function with arguments object.
   ASSERT(!function->shared()->uses_arguments());
 
   Handle<Code> result = Handle<Code>::null();
   BailoutId ast_id = BailoutId::None();
 
-  if (FLAG_concurrent_recompilation && FLAG_concurrent_osr) {
+  if (FLAG_concurrent_osr) {
     if (isolate->optimizing_compiler_thread()->
             IsQueuedForOSR(function, pc_offset)) {
       // Still waiting for the optimizing compiler thread to finish.  Carry on.
       if (FLAG_trace_osr) {
         PrintF("[COSR - polling recompile tasks for ");
         function->PrintName();
         PrintF("]\n");
       }
       return NULL;
     }
 
     OptimizingCompiler* compiler = isolate->optimizing_compiler_thread()->
         FindReadyOSRCandidate(function, pc_offset);
 
     if (compiler == NULL) {
       if (IsSuitableForOnStackReplacement(isolate, function, unoptimized) &&
           Compiler::RecompileConcurrent(function, pc_offset)) {
         if (function->IsMarkedForLazyRecompilation() ||
             function->IsMarkedForConcurrentRecompilation()) {
           // Prevent regular recompilation if we queue this for OSR.
           // TODO(yangguo): remove this as soon as OSR becomes one-shot.
-          function->ReplaceCode(function->shared()->code());
+          function->ReplaceCode(*unoptimized);
         }
         return NULL;
       }
       // Fall through to the end in case of failure.
     } else {
       // TODO(titzer): don't install the OSR code into the function.
       ast_id = compiler->info()->osr_ast_id();
       result = Compiler::InstallOptimizedCode(compiler);
     }
   } else if (IsSuitableForOnStackReplacement(isolate, function, unoptimized)) {
@@ skipping 6155 matching lines @@
     // Handle last resort GC and make sure to allow future allocations
     // to grow the heap without causing GCs (if possible).
     isolate->counters()->gc_last_resort_from_js()->Increment();
     isolate->heap()->CollectAllGarbage(Heap::kNoGCFlags,
                                        "Runtime::PerformGC");
   }
 }
 
 
 } }  // namespace v8::internal