Refactor CpuProfiler.

src/log.cc

Index: src/log.cc
diff --git a/src/log.cc b/src/log.cc
index 040109535b247f2cf660b7f3e5646fef23afed89..8bd05d9a1309c2521b17afd9b513d8ed46db40c4 100644
--- a/src/log.cc
+++ b/src/log.cc
@@ -22,6 +22,7 @@
 #include "src/macro-assembler.h"
 #include "src/perf-jit.h"
 #include "src/profiler/cpu-profiler-inl.h"
+#include "src/profiler/profiler-listener.h"
 #include "src/runtime-profiler.h"
 #include "src/string-stream.h"
 #include "src/vm-state-inl.h"
@@ -759,6 +760,7 @@ Logger::Logger(Isolate* isolate)
 
 Logger::~Logger() {
   delete log_;
+  profiler_listener_.reset();

[alph, 2016/06/19 03:05:40]

nit: don't need this

[lpy, 2016/06/20 17:16:55]

Done.

 }
 
 void Logger::addCodeEventListener(CodeEventListener* listener) {
@@ -1789,6 +1791,8 @@ bool Logger::SetUp(Isolate* isolate) {
     profiler_->Engage();
   }
 
+  profiler_listener_.reset();
+
   if (is_logging_) {
     addCodeEventListener(this);
   }
@@ -1816,6 +1820,20 @@ void Logger::SetCodeEventHandler(uint32_t options,
   }
 }
 
+void Logger::SetUpProfilerListener() {
+  if (!is_initialized_) return;
+  if (profiler_listener_.get()) {

[alph, 2016/06/19 03:05:40]

nit:
if (!listener)
  listener.reset(new ...);
addCodeEvent...

[lpy, 2016/06/20 17:16:55]

Done.

+    addCodeEventListener(profiler_listener_.get());
+    return;
+  }
+  profiler_listener_.reset(new ProfilerListener(isolate_));
+  addCodeEventListener(profiler_listener_.get());
+}
+
+void Logger::TearDownProfilerListener() {
+  if (profiler_listener_->HasObserver()) return;

[alph, 2016/06/19 03:05:40]

maybe DCHECK(!HasObserver);

[lpy, 2016/06/20 17:16:55]

The reason I don't put DCHECK here, is that I assume for one isolate, we have
one profiler listener and we can have many observers in it, each observer will
call TearDownProfilerListener at some point, so DCHECK is not the case.

I will leave this and check in the code. We can change it later.

+  removeCodeEventListener(profiler_listener_.get());
+}
 
 sampler::Sampler* Logger::sampler() {
   return ticker_;
@@ -1860,6 +1878,10 @@ FILE* Logger::TearDown() {
     jit_logger_ = NULL;
   }
 
+  if (profiler_listener_.get()) {

[alph, 2016/06/19 03:05:40]

I believe it has an implicit conversion to bool.

[lpy, 2016/06/20 17:16:55]

Done.

+    removeCodeEventListener(profiler_listener_.get());
+  }
+
   return log_->Close();
 }