Add macro for getting a PropertyAttributes for the runtime functions

src/runtime/runtime-utils.h

 // Copyright 2014 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_RUNTIME_RUNTIME_UTILS_H_
 #define V8_RUNTIME_RUNTIME_UTILS_H_
 
 
 namespace v8 {
 namespace internal {
@@ skipping 69 matching lines @@
 
 // Assert that the given argument is a number within the Int32 range
 // and convert it to int32_t.  If the argument is not an Int32 call
 // IllegalOperation and return.
 #define CONVERT_INT32_ARG_CHECKED(name, index) \
   RUNTIME_ASSERT(args[index]->IsNumber());     \
   int32_t name = 0;                            \
   RUNTIME_ASSERT(args[index]->ToInt32(&name));
 
 
+// Cast the given argument to PropertyAttributes and store its value in a
+// variable with the given name.  If the argument is not a Smi call or the
+// enum value is out of range, call IllegalOperation and return.
+#define CONVERT_PROPERTY_ATTRIBUTES_CHECKED(name, index)                   \
+  RUNTIME_ASSERT(args[index]->IsSmi());                                    \
+  RUNTIME_ASSERT(                                                          \
+      (args.smi_at(index) & ~(READ_ONLY | DONT_ENUM | DONT_DELETE)) == 0); \
+  PropertyAttributes name = static_cast<PropertyAttributes>(args.smi_at(index));
+
+
 // A mechanism to return a pair of Object pointers in registers (if possible).
 // How this is achieved is calling convention-dependent.
 // All currently supported x86 compiles uses calling conventions that are cdecl
 // variants where a 64-bit value is returned in two 32-bit registers
 // (edx:eax on ia32, r1:r0 on ARM).
 // In AMD-64 calling convention a struct of two pointers is returned in rdx:rax.
 // In Win64 calling convention, a struct of two pointers is returned in memory,
 // allocated by the caller, and passed as a pointer in a hidden first parameter.
 #ifdef V8_HOST_ARCH_64_BIT
 struct ObjectPair {
@@ skipping 37 matching lines @@
 #else
 #error Unknown endianness
 #endif
 }
 #endif
 
 }
 }  // namespace v8::internal
 
 #endif  // V8_RUNTIME_RUNTIME_UTILS_H_