Implements a new API to set a function entry hook for profiling.

src/v8.h

Index: src/v8.h
diff --git a/src/v8.h b/src/v8.h
index 67716d8107a6014181d3cbd646e8ae561d8c694c..afb0d4e4d59fa71cf1a3fc08b9a6d22d4c30e925 100644
--- a/src/v8.h
+++ b/src/v8.h
@@ -99,6 +99,12 @@ class V8 : public AllStatic {
   // Support for return-address rewriting profilers.
   static void SetReturnAddressLocationResolver(
       ReturnAddressLocationResolver resolver);
+  // Support for a function entry profiling hook.
+  static bool SetFunctionEntryHook(FunctionEntryHook entry_hook);
+  // Returns the location of the function entry profiling hook.
+  static const FunctionEntryHook* GetFunctionEntryHookLocation();
+  // Returns a function that dispatches to the entry profiling hook.
+  static FunctionEntryHook GetFunctionEntryHookDispatcher();

[danno, 2012/07/10 09:37:13]

Why does the dispatch need to be exposed in the API? I don't think this is
something clients need to be able to call. In any case, there seem to be no
tests of this.

[Sigurður Ásgeirsson, 2012/07/11 14:50:34]

This is src/v8.h, in namespace internal::V8, which I had read to be the
API<->implementation interface layer.
The API I had read to be defined in include/v8.h, which only contains the single
API function addition I intended to make.
This is tested through the unittest, as these are only used by internal
implementation.

   // Random number generation support. Not cryptographically safe.
   static uint32_t Random(Context* context);
   // We use random numbers internally in memory allocation and in the