src/base/macros.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_BASE_MACROS_H_
#define V8_BASE_MACROS_H_

#include "../../include/v8stdint.h"


// The expression OFFSET_OF(type, field) computes the byte-offset
// of the specified field relative to the containing type. This
// corresponds to 'offsetof' (in stddef.h), except that it doesn't
// use 0 or NULL, which causes a problem with the compiler warnings
// we have enabled (which is also why 'offsetof' doesn't seem to work).
// Here we simply use the non-zero value 4, which seems to work.
#define OFFSET_OF(type, field)                                          \
  (reinterpret_cast<intptr_t>(&(reinterpret_cast<type*>(4)->field)) - 4)


// The expression ARRAY_SIZE(a) is a compile-time constant of type
// size_t which represents the number of elements of the given
// array. You should only use ARRAY_SIZE on statically allocated
// arrays.
#define ARRAY_SIZE(a)                                   \
  ((sizeof(a) / sizeof(*(a))) /                         \
  static_cast<size_t>(!(sizeof(a) % sizeof(*(a)))))


// A macro to disallow the evil copy constructor and operator= functions
// This should be used in the private: declarations for a class
#define DISALLOW_COPY_AND_ASSIGN(TypeName)  \
  TypeName(const TypeName&) V8_DELETE;      \
  void operator=(const TypeName&) V8_DELETE


// A macro to disallow all the implicit constructors, namely the
// default constructor, copy constructor and operator= functions.
//
// This should be used in the private: declarations for a class
// that wants to prevent anyone from instantiating it. This is
// especially useful for classes containing only static methods.
#define DISALLOW_IMPLICIT_CONSTRUCTORS(TypeName)  \
  TypeName() V8_DELETE;                           \
  DISALLOW_COPY_AND_ASSIGN(TypeName)


// Newly written code should use V8_INLINE and V8_NOINLINE directly.
#define INLINE(declarator)    V8_INLINE declarator
#define NO_INLINE(declarator) V8_NOINLINE declarator


// Newly written code should use V8_WARN_UNUSED_RESULT.
#define MUST_USE_RESULT V8_WARN_UNUSED_RESULT


// Define DISABLE_ASAN macros.
#if defined(__has_feature)
#if __has_feature(address_sanitizer)
#define DISABLE_ASAN __attribute__((no_sanitize_address))
#endif
#endif


#ifndef DISABLE_ASAN
#define DISABLE_ASAN
#endif


#if V8_CC_GNU
#define V8_IMMEDIATE_CRASH() __builtin_trap()
#else
#define V8_IMMEDIATE_CRASH() ((void(*)())0)()
#endif

#endif   // V8_BASE_MACROS_H_