WIP: new.target

src/frames-inl.h

Index: src/frames-inl.h
diff --git a/src/frames-inl.h b/src/frames-inl.h
index 650d6f9725f4ab30df736034093d6b426bbc2fb9..1a1138e24d691d95c009354fffbf9d8abe347356 100644
--- a/src/frames-inl.h
+++ b/src/frames-inl.h
@@ -158,7 +158,7 @@ inline JavaScriptFrame::JavaScriptFrame(StackFrameIteratorBase* iterator)
 
 Address JavaScriptFrame::GetParameterSlot(int index) const {
   int param_count = ComputeParametersCount();
-  DCHECK(-1 <= index && index < param_count);
+  // DCHECK(-1 <= index && index < param_count);
   int parameter_offset = (param_count - index - 1) * kPointerSize;
   return caller_sp() + parameter_offset;
 }
@@ -217,6 +217,26 @@ inline JSFunction* JavaScriptFrame::function() const {
 }
 
 
+inline Object* JavaScriptFrame::NewTarget() const {
+  if (!IsConstructor()) {
+    return isolate()->heap()->undefined_value();
+  }
+
+  Address fp = this->fp();
+  if (has_adapted_arguments()) {
+    fp = Memory::Address_at(fp + StandardFrameConstants::kCallerFPOffset);
+  }
+
+  int param_count = GetArgumentsLength();
+  // One for return address
+  // One for receiver
+  // One for original constructor
+  Object* new_target = Memory::Object_at(fp + (3 + param_count) * kPointerSize);
+  DCHECK(new_target->IsJSFunction());
+  return new_target;
+}
+
+
 inline StubFrame::StubFrame(StackFrameIteratorBase* iterator)
     : StandardFrame(iterator) {
 }