[turbofan] Enable concurrent (re)compilation.

src/optimizing-compile-dispatcher.cc

 // Copyright 2012 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "src/optimizing-compile-dispatcher.h"
 
 #include "src/v8.h"
 
 #include "src/base/atomicops.h"
 #include "src/full-codegen.h"
@@ skipping 15 matching lines @@
         // Remove stack check that guards OSR entry on original code.
         Handle<Code> code = info->unoptimized_code();
         uint32_t offset = code->TranslateAstIdToPcOffset(info->osr_ast_id());
         BackEdgeTable::RemoveStackCheck(code, offset);
       }
     } else {
       Handle<JSFunction> function = info->closure();
       function->ReplaceCode(function->shared()->code());
     }
   }
+  // TODO(bmeurer): Improve resource management for OptimizedCompileJob.
+  job->~OptimizedCompileJob();
   delete info;
 }
 
 }  // namespace
 
 
 class OptimizingCompileDispatcher::CompileTask : public v8::Task {
  public:
   explicit CompileTask(Isolate* isolate) : isolate_(isolate) {
     OptimizingCompileDispatcher* dispatcher =
@@ skipping 305 matching lines @@
       info->closure()->PrintName();
       PrintF(", AST id %d]\n", info->osr_ast_id().ToInt());
     }
     DisposeOptimizedCompileJob(stale, false);
   }
   osr_buffer_[osr_buffer_cursor_] = job;
   osr_buffer_cursor_ = (osr_buffer_cursor_ + 1) % osr_buffer_capacity_;
 }
 }  // namespace internal
 }  // namespace v8