const.h 839 B

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  1. /* SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note */
  2. #ifndef _LINUX_CONST_H
  3. #define _LINUX_CONST_H
  4. /* const.h: Macros for dealing with constants. */
  5. /* Some constant macros are used in both assembler and
  6. * C code. Therefore we cannot annotate them always with
  7. * 'UL' and other type specifiers unilaterally. We
  8. * use the following macros to deal with this.
  9. *
  10. * Similarly, _AT() will cast an expression with a type in C, but
  11. * leave it unchanged in asm.
  12. */
  13. #ifdef __ASSEMBLY__
  14. #define _AC(X,Y) X
  15. #define _AT(T,X) X
  16. #else
  17. #define __AC(X,Y) (X##Y)
  18. #define _AC(X,Y) __AC(X,Y)
  19. #define _AT(T,X) ((T)(X))
  20. #endif
  21. #define _UL(x) (_AC(x, UL))
  22. #define _ULL(x) (_AC(x, ULL))
  23. #define _BITUL(x) (_UL(1) << (x))
  24. #define _BITULL(x) (_ULL(1) << (x))
  25. #define UL(x) (_UL(x))
  26. #define ULL(x) (_ULL(x))
  27. #endif /* _LINUX_CONST_H */