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/* SPDX-License-Identifier: GPL-2.0-only */
/* const.h: Macros for dealing with constants. */
#ifndef _LINUX_CONST_H
#define _LINUX_CONST_H
/* Some constant macros are used in both assembler and
* C code. Therefore we cannot annotate them always with
* 'UL' and other type specifiers unilaterally. We
* use the following macros to deal with this.
*
* Similarly, _AT() will cast an expression with a type in C, but
* leave it unchanged in asm.
*/
#ifdef __ASSEMBLY__
#define _AC(X,Y) X
#define _AT(T,X) X
#else
#define __AC(X,Y) (X##Y)
#define _AC(X,Y) __AC(X,Y)
#define _AT(T,X) ((T)(X))
#endif
#define _UL(x) (_AC(x, UL))
#define _ULL(x) (_AC(x, ULL))
#define _BITUL(x) (_UL(1) << (x))
#define _BITULL(x) (_ULL(1) << (x))
#define UL(x) (_UL(x))
#define ULL(x) (_ULL(x))
/*
* This returns a constant expression while determining if an argument is
* a constant expression, most importantly without evaluating the argument.
* Glory to Martin Uecker <Martin.Uecker@med.uni-goettingen.de>
*/
#define __is_constexpr(x) \
(sizeof(int) == sizeof(*(8 ? ((void *)((long)(x) * 0l)) : (int *)8)))
#endif /* !(_LINUX_CONST_H) */
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