arch/sh/include/asm/word-at-a-time.h

   1 #ifndef __ASM_SH_WORD_AT_A_TIME_H
   2 #define __ASM_SH_WORD_AT_A_TIME_H
   3
   4 #ifdef CONFIG_CPU_BIG_ENDIAN
   5 # include <asm-generic/word-at-a-time.h>
   6 #else
   7 /*
   8  * Little-endian version cribbed from x86.
   9  */
  10 struct word_at_a_time {
  11         const unsigned long one_bits, high_bits;
  12 };
  13
  14 #define WORD_AT_A_TIME_CONSTANTS { REPEAT_BYTE(0x01), REPEAT_BYTE(0x80) }
  15
  16 /* Carl Chatfield / Jan Achrenius G+ version for 32-bit */
  17 static inline long count_masked_bytes(long mask)
  18 {
  19         /* (000000 0000ff 00ffff ffffff) -> ( 1 1 2 3 ) */
  20         long a = (0x0ff0001+mask) >> 23;
  21         /* Fix the 1 for 00 case */
  22         return a & mask;
  23 }
  24
  25 /* Return nonzero if it has a zero */
  26 static inline unsigned long has_zero(unsigned long a, unsigned long *bits, const struct word_at_a_time *c)
  27 {
  28         unsigned long mask = ((a - c->one_bits) & ~a) & c->high_bits;
  29         *bits = mask;
  30         return mask;
  31 }
  32
  33 static inline unsigned long prep_zero_mask(unsigned long a, unsigned long bits, const struct word_at_a_time *c)
  34 {
  35         return bits;
  36 }
  37
  38 static inline unsigned long create_zero_mask(unsigned long bits)
  39 {
  40         bits = (bits - 1) & ~bits;
  41         return bits >> 7;
  42 }
  43
  44 /* The mask we created is directly usable as a bytemask */
  45 #define zero_bytemask(mask) (mask)
  46
  47 static inline unsigned long find_zero(unsigned long mask)
  48 {
  49         return count_masked_bytes(mask);
  50 }
  51 #endif
  52
  53 #endif