diff options
Diffstat (limited to 'arch/powerpc/include/asm/word-at-a-time.h')
-rw-r--r-- | arch/powerpc/include/asm/word-at-a-time.h | 41 |
1 files changed, 41 insertions, 0 deletions
diff --git a/arch/powerpc/include/asm/word-at-a-time.h b/arch/powerpc/include/asm/word-at-a-time.h new file mode 100644 index 000000000000..d0b6d4ac6dda --- /dev/null +++ b/arch/powerpc/include/asm/word-at-a-time.h @@ -0,0 +1,41 @@ +#ifndef _ASM_WORD_AT_A_TIME_H +#define _ASM_WORD_AT_A_TIME_H + +/* + * Word-at-a-time interfaces for PowerPC. + */ + +#include <linux/kernel.h> +#include <asm/asm-compat.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 leading_zero_bits; + + asm (PPC_CNTLZL "%0,%1" : "=r" (leading_zero_bits) : "r" (mask)); + return leading_zero_bits >> 3; +} + +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; +} + +#endif /* _ASM_WORD_AT_A_TIME_H */ |