LXR linux/arch/unicore32/include/asm/bitops.h

   1/*
   2 * linux/arch/unicore32/include/asm/bitops.h
   3 *
   4 * Code specific to PKUnity SoC and UniCore ISA
   5 *
   6 * Copyright (C) 2001-2010 GUAN Xue-tao
   7 *
   8 * This program is free software; you can redistribute it and/or modify
   9 * it under the terms of the GNU General Public License version 2 as
  10 * published by the Free Software Foundation.
  11 */
  12
  13#ifndef __UNICORE_BITOPS_H__
  14#define __UNICORE_BITOPS_H__
  15
  16#define _ASM_GENERIC_BITOPS_FLS_H_
  17#define _ASM_GENERIC_BITOPS___FLS_H_
  18#define _ASM_GENERIC_BITOPS_FFS_H_
  19#define _ASM_GENERIC_BITOPS___FFS_H_
  20/*
  21 * On UNICORE, those functions can be implemented around
  22 * the cntlz instruction for much better code efficiency.
  23 */
  24
  25static inline int fls(int x)
  26{
  27        int ret;
  28
  29        asm("cntlz\t%0, %1" : "=r" (ret) : "r" (x) : "cc");
  30        ret = 32 - ret;
  31
  32        return ret;
  33}
  34
  35#define __fls(x) (fls(x) - 1)
  36#define ffs(x) ({ unsigned long __t = (x); fls(__t & -__t); })
  37#define __ffs(x) (ffs(x) - 1)
  38
  39#include <asm-generic/bitops.h>
  40
  41/* following definitions: to avoid using codes in lib/find_*.c */
  42#define find_next_bit           find_next_bit
  43#define find_next_zero_bit      find_next_zero_bit
  44#define find_first_bit          find_first_bit
  45#define find_first_zero_bit     find_first_zero_bit
  46
  47#endif /* __UNICORE_BITOPS_H__ */
  48