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#ifndef __ASM_ARM_WORD_AT_A_TIME_H
#define __ASM_ARM_WORD_AT_A_TIME_H
#ifndef __ARMEB__
/*
* Little-endian word-at-a-time zero byte handling.
* Heavily based on the x86 algorithm.
*/
#include <linux/kernel.h>
struct word_at_a_time {
const unsigned long one_bits, high_bits;
};
#define WORD_AT_A_TIME_CONSTANTS { REPEAT_BYTE(0x01), REPEAT_BYTE(0x80) }
static inline unsigned long has_zero(unsigned long a, unsigned long *bits,
const struct word_at_a_time *c)
{
unsigned long mask = ((a - c->one_bits) & ~a) & c->high_bits;
*bits = mask;
return mask;
}
#define prep_zero_mask(a, bits, c) (bits)
static inline unsigned long create_zero_mask(unsigned long bits)
{
bits = (bits - 1) & ~bits;
return bits >> 7;
}
static inline unsigned long find_zero(unsigned long mask)
{
unsigned long ret;
#if __LINUX_ARM_ARCH__ >= 5
/* We have clz available. */
ret = fls(mask) >> 3;
#else
/* (000000 0000ff 00ffff ffffff) -> ( 1 1 2 3 ) */
ret = (0x0ff0001 + mask) >> 23;
/* Fix the 1 for 00 case */
ret &= mask;
#endif
return ret;
}
#else /* __ARMEB__ */
#include <asm-generic/word-at-a-time.h>
#endif
#endif /* __ASM_ARM_WORD_AT_A_TIME_H */
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