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#ifndef _ASM_WORD_AT_A_TIME_H
#define _ASM_WORD_AT_A_TIME_H
/*
* This says "generic", but it's actually big-endian only.
* Little-endian can use more efficient versions of these
* interfaces, see for example
* arch/x86/include/asm/word-at-a-time.h
* for those.
*/
#include <linux/kernel.h>
struct word_at_a_time {
const unsigned long high_bits, low_bits;
};
#define WORD_AT_A_TIME_CONSTANTS { REPEAT_BYTE(0xfe) + 1, REPEAT_BYTE(0x7f) }
/* Bit set in the bytes that have a zero */
static inline long prep_zero_mask(unsigned long val, unsigned long rhs, const struct word_at_a_time *c)
{
unsigned long mask = (val & c->low_bits) + c->low_bits;
return ~(mask | rhs);
}
#define create_zero_mask(mask) (mask)
static inline long find_zero(unsigned long mask)
{
long byte = 0;
#ifdef CONFIG_64BIT
if (mask >> 32)
mask >>= 32;
else
byte = 4;
#endif
if (mask >> 16)
mask >>= 16;
else
byte += 2;
return (mask >> 8) ? byte : byte + 1;
}
static inline bool has_zero(unsigned long val, unsigned long *data, const struct word_at_a_time *c)
{
unsigned long rhs = val | c->low_bits;
*data = rhs;
return (val + c->high_bits) & ~rhs;
}
#ifndef zero_bytemask
#define zero_bytemask(mask) (~0ul << __fls(mask) << 1)
#endif
#endif /* _ASM_WORD_AT_A_TIME_H */
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