Attempt to reduce performance penalty for logging and profiling

src/log.h

Index: src/log.h
===================================================================
--- src/log.h	(revision 2260)
+++ src/log.h	(working copy)
@@ -28,6 +28,9 @@
 #ifndef V8_LOG_H_
 #define V8_LOG_H_
 
+#include "platform.h"
+#include "log-utils.h"
+
 namespace v8 {
 namespace internal {
 
@@ -77,7 +80,7 @@
 #ifdef ENABLE_LOGGING_AND_PROFILING
 #define LOG(Call)                           \
   do {                                      \
-    if (v8::internal::Logger::IsEnabled()) \
+    if (v8::internal::Logger::is_logging()) \
       v8::internal::Logger::Call;           \
   } while (false)
 #else
@@ -88,12 +91,13 @@
 class VMState BASE_EMBEDDED {
 #ifdef ENABLE_LOGGING_AND_PROFILING
  public:
-  explicit VMState(StateTag state);
-  ~VMState();
+  inline explicit VMState(StateTag state);
+  inline ~VMState();
 
   StateTag state() { return state_; }
 
  private:
+  bool disabled_;
   StateTag state_;
   VMState* previous_;
 #else
@@ -236,7 +240,9 @@
     return current_state_ ? current_state_->state() : OTHER;
   }
 
-  static bool IsEnabled();
+  static bool is_logging() {
+    return is_logging_;
+  }
 
   // Pause/Resume collection of profiling data.
   // When data collection is paused, Tick events are discarded until
@@ -317,8 +323,10 @@
   friend class VMState;
 
   friend class LoggerTestHelper;
+
+  static bool is_logging_;
 #else
-  static bool is_enabled() { return false; }
+  static bool is_logging() { return false; }
 #endif
 };