bitsperlong.h 1.2 KB

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  1. /* SPDX-License-Identifier: GPL-2.0 */
  2. #ifndef __ASM_GENERIC_BITS_PER_LONG
  3. #define __ASM_GENERIC_BITS_PER_LONG
  4. #include <uapi/asm-generic/bitsperlong.h>
  5. #ifdef CONFIG_64BIT
  6. #define BITS_PER_LONG 64
  7. #else
  8. #define BITS_PER_LONG 32
  9. #endif /* CONFIG_64BIT */
  10. /*
  11. * FIXME: The check currently breaks x86-64 build, so it's
  12. * temporarily disabled. Please fix x86-64 and reenable
  13. */
  14. #if 0 && BITS_PER_LONG != __BITS_PER_LONG
  15. #error Inconsistent word size. Check asm/bitsperlong.h
  16. #endif
  17. #ifndef BITS_PER_LONG_LONG
  18. #define BITS_PER_LONG_LONG 64
  19. #endif
  20. /*
  21. * small_const_nbits(n) is true precisely when it is known at compile-time
  22. * that BITMAP_SIZE(n) is 1, i.e. 1 <= n <= BITS_PER_LONG. This allows
  23. * various bit/bitmap APIs to provide a fast inline implementation. Bitmaps
  24. * of size 0 are very rare, and a compile-time-known-size 0 is most likely
  25. * a sign of error. They will be handled correctly by the bit/bitmap APIs,
  26. * but using the out-of-line functions, so that the inline implementations
  27. * can unconditionally dereference the pointer(s).
  28. */
  29. #define small_const_nbits(nbits) \
  30. (__builtin_constant_p(nbits) && (nbits) <= BITS_PER_LONG && (nbits) > 0)
  31. #endif /* __ASM_GENERIC_BITS_PER_LONG */