diff options
Diffstat (limited to 'arch/sh/include/asm/word-at-a-time.h')
-rw-r--r-- | arch/sh/include/asm/word-at-a-time.h | 53 |
1 files changed, 53 insertions, 0 deletions
diff --git a/arch/sh/include/asm/word-at-a-time.h b/arch/sh/include/asm/word-at-a-time.h new file mode 100644 index 0000000..6e38953 --- /dev/null +++ b/arch/sh/include/asm/word-at-a-time.h @@ -0,0 +1,53 @@ +#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 |