linux-stable/include/uapi/linux/const.h
Masahiro Yamada 21e7bc600e linux/const.h: refactor _BITUL and _BITULL a bit
Minor cleanups available by _UL and _ULL.

Link: http://lkml.kernel.org/r/1519301715-31798-5-git-send-email-yamada.masahiro@socionext.com
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: David Howells <dhowells@redhat.com>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Guan Xuetao <gxt@mprc.pku.edu.cn>
Cc: Russell King <rmk+kernel@armlinux.org.uk>
Cc: Will Deacon <will.deacon@arm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-04-11 10:28:38 -07:00

31 lines
803 B
C

/* SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note */
/* const.h: Macros for dealing with constants. */
#ifndef _UAPI_LINUX_CONST_H
#define _UAPI_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))
#endif /* _UAPI_LINUX_CONST_H */