diff options
Diffstat (limited to 'V8Binding/v8/src/builtins.cc')
| -rw-r--r-- | V8Binding/v8/src/builtins.cc | 26 |
1 files changed, 21 insertions, 5 deletions
diff --git a/V8Binding/v8/src/builtins.cc b/V8Binding/v8/src/builtins.cc index 0648e54..1ea0245 100644 --- a/V8Binding/v8/src/builtins.cc +++ b/V8Binding/v8/src/builtins.cc @@ -87,18 +87,34 @@ static inline Object* __builtin_arg__(int n, int argc, Object** argv) { } -// TODO(1238487): Get rid of this function that determines if the -// builtin is called as a constructor. This may be a somewhat slow -// operation due to the stack frame iteration. static inline bool CalledAsConstructor() { +#ifdef DEBUG + // Calculate the result using a full stack frame iterator and check + // that the state of the stack is as we assume it to be in the + // code below. StackFrameIterator it; ASSERT(it.frame()->is_exit()); it.Advance(); StackFrame* frame = it.frame(); - return frame->is_construct(); + bool reference_result = frame->is_construct(); +#endif + Address fp = Top::c_entry_fp(Top::GetCurrentThread()); + // Because we know fp points to an exit frame we can use the relevant + // part of ExitFrame::ComputeCallerState directly. + const int kCallerOffset = ExitFrameConstants::kCallerFPOffset; + Address caller_fp = Memory::Address_at(fp + kCallerOffset); + // This inlines the part of StackFrame::ComputeType that grabs the + // type of the current frame. Note that StackFrame::ComputeType + // has been specialized for each architecture so if any one of them + // changes this code has to be changed as well. + const int kMarkerOffset = StandardFrameConstants::kMarkerOffset; + const Smi* kConstructMarker = Smi::FromInt(StackFrame::CONSTRUCT); + Object* marker = Memory::Object_at(caller_fp + kMarkerOffset); + bool result = (marker == kConstructMarker); + ASSERT_EQ(result, reference_result); + return result; } - // ---------------------------------------------------------------------------- |