word-at-a-time.h

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#ifndef __ASM_SH_WORD_AT_A_TIME_H
#define __ASM_SH_WORD_AT_A_TIME_H

#ifdef CONFIG_CPU_BIG_ENDIAN
# include <asm-generic/word-at-a-time.h>
#else
/*
 * Little-endian version cribbed from x86.
 */
struct word_at_a_time {
    const unsigned long one_bits, high_bits;
};

#define WORD_AT_A_TIME_CONSTANTS { REPEAT_BYTE(0x01), REPEAT_BYTE(0x80) }

/* Carl Chatfield / Jan Achrenius G+ version for 32-bit */
static inline long count_masked_bytes(long mask)
{
    /* (000000 0000ff 00ffff ffffff) -> ( 1 1 2 3 ) */
    long a = (0x0ff0001+mask) >> 23;
    /* Fix the 1 for 00 case */
    return a & mask;
}

/* Return nonzero if it has a zero */
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;
}

static inline unsigned long prep_zero_mask(unsigned long a, unsigned long bits, const struct word_at_a_time *c)
{
    return bits;
}

static inline unsigned long create_zero_mask(unsigned long bits)
{
    bits = (bits - 1) & ~bits;
    return bits >> 7;
}

/* The mask we created is directly usable as a bytemask */
#define zero_bytemask(mask) (mask)

static inline unsigned long find_zero(unsigned long mask)
{
    return count_masked_bytes(mask);
}
#endif

#endif