Initial GetSample implementation.

src/api.cc

Index: src/api.cc
diff --git a/src/api.cc b/src/api.cc
index 7c484de53ee1e537a8abeefdce1e0cab69e4952e..cb3385dac0298fc06042ce1461f0fc37ac7acd65 100644
--- a/src/api.cc
+++ b/src/api.cc
@@ -11,6 +11,7 @@
 #include <cmath>  // For isnan.
 #include "include/v8-debug.h"
 #include "include/v8-profiler.h"
+#include "include/v8-sampler.h"
 #include "include/v8-testing.h"
 #include "src/assert-scope.h"
 #include "src/base/platform/platform.h"
@@ -7425,6 +7426,22 @@ void HeapProfiler::SetRetainedObjectInfo(UniqueId id,
   reinterpret_cast<i::HeapProfiler*>(this)->SetRetainedObjectInfo(id, info);
 }
 
+Sample* Sampler::GetSample(Isolate* isolate,
+                           Sample* sample) {
+  i::Isolate* isolate_ = reinterpret_cast<i::Isolate*>(isolate);
+
+  i::CpuProfiler* profiler_ = isolate_->cpu_profiler();
+  if (profiler_ == NULL) return NULL;
+
+  i::ProfilerEventsProcessor* processor_ = profiler_->processor();
+  if (processor_ == NULL) return NULL;
+
+  i::Sampler* sampler_ = processor_->sampler();
+  if (sampler_ == NULL) return NULL;

[fmeawad, 2014/07/29 18:30:50]

Can you cache those between calls?
i.e. check and store, start with sampler_ all the way back.

Also I think _ indicates private, with local variables do not use _ (double
check the coding guidelines).

[gholap, 2014/07/29 23:25:20]

Acknowledged.

+
+  return reinterpret_cast<Sample*>(
+    sampler_->GetSample(reinterpret_cast<i::TickSample*>(sample)));
+}
 
 v8::Testing::StressType internal::Testing::stress_type_ =
     v8::Testing::kStressTypeOpt;