Initial implementation of GetStackSample sampling profiler API.

src/sampler.h

 // Copyright 2013 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.
 
 #ifndef V8_SAMPLER_H_
 #define V8_SAMPLER_H_
 
+#include "include/v8.h"
+
 #include "src/base/atomicops.h"
 #include "src/frames.h"
 #include "src/globals.h"
 
 namespace v8 {
 namespace internal {
 
 class Isolate;
 
 // ----------------------------------------------------------------------------
 // Sampler
 //
 // A sampler periodically samples the state of the VM and optionally
 // (if used for profiling) the program counter and stack pointer for
 // the thread that created it.
 
-struct RegisterState {
-  RegisterState() : pc(NULL), sp(NULL), fp(NULL) {}
-  Address pc;      // Instruction pointer.
-  Address sp;      // Stack pointer.
-  Address fp;      // Frame pointer.
-};
-
 // TickSample captures the information collected for each sample.
 struct TickSample {
   TickSample()
       : state(OTHER),
         pc(NULL),
         external_callback(NULL),
         frames_count(0),
         has_external_callback(false),
         top_frame_type(StackFrame::NONE) {}
-  void Init(Isolate* isolate, const RegisterState& state);
+  void Init(Isolate* isolate, const v8::RegisterState& state);
+  static int GetStackSample(Isolate* isolate, const v8::RegisterState& state,
+                            void** frames, int frames_limit);
   StateTag state;  // The state of the VM.
   Address pc;      // Instruction pointer.
   union {
     Address tos;   // Top stack value (*sp).
     Address external_callback;
   };
   static const unsigned kMaxFramesCountLog2 = 8;
   static const unsigned kMaxFramesCount = (1 << kMaxFramesCountLog2) - 1;
   Address stack[kMaxFramesCount];  // Call stack.
   base::TimeTicks timestamp;
   unsigned frames_count : kMaxFramesCountLog2;  // Number of captured frames.
   bool has_external_callback : 1;
   StackFrame::Type top_frame_type : 4;
 };
 
 class Sampler {
  public:
   // Initializes the Sampler support. Called once at VM startup.
   static void SetUp();
   static void TearDown();
 
   // Initialize sampler.
   Sampler(Isolate* isolate, int interval);
   virtual ~Sampler();
 
   Isolate* isolate() const { return isolate_; }
   int interval() const { return interval_; }
 
   // Performs stack sampling.
-  void SampleStack(const RegisterState& regs);
+  void SampleStack(const v8::RegisterState& regs);
 
   // Start and stop sampler.
   void Start();
   void Stop();
 
   // Whether the sampling thread should use this Sampler for CPU profiling?
   bool IsProfiling() const {
     return base::NoBarrier_Load(&profiling_) > 0 &&
         !base::NoBarrier_Load(&has_processing_thread_);
   }
@@ skipping 39 matching lines @@
   bool is_counting_samples_;
   // Counts stack samples taken in JS VM state.
   unsigned js_and_external_sample_count_;
   DISALLOW_IMPLICIT_CONSTRUCTORS(Sampler);
 };
 
 
 } }  // namespace v8::internal
 
 #endif  // V8_SAMPLER_H_