[WIP] Initial CallFunctionCallback builtin.

src/x64/macro-assembler-x64.h

 // Copyright 2012 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_X64_MACRO_ASSEMBLER_X64_H_
 #define V8_X64_MACRO_ASSEMBLER_X64_H_
 
 #include "src/bailout-reason.h"
 #include "src/base/flags.h"
 #include "src/frames.h"
@@ skipping 1147 matching lines @@
   void AssertBoundFunction(Register object);
 
   // Abort execution if argument is not a JSGeneratorObject,
   // enabled via --debug-code.
   void AssertGeneratorObject(Register object, Register suspend_flags);
 
   // Abort execution if argument is not undefined or an AllocationSite, enabled
   // via --debug-code.
   void AssertUndefinedOrAllocationSite(Register object);
 
+  // Abort if argument is not a valid API call result, enabled via --debug-code.
+  void AssertApiCallResult(Register object);
+
   // ---------------------------------------------------------------------------
   // Exception handling
 
   // Push a new stack handler and link it into stack handler chain.
   void PushStackHandler();
 
   // Unlink the stack handler on top of the stack from the stack handler chain.
   void PopStackHandler();
 
   // ---------------------------------------------------------------------------
@@ skipping 391 matching lines @@
 inline Operand StackOperandForReturnAddress(int32_t disp) {
   return Operand(rsp, disp);
 }
 
 #define ACCESS_MASM(masm) masm->
 
 }  // namespace internal
 }  // namespace v8
 
 #endif  // V8_X64_MACRO_ASSEMBLER_X64_H_