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

   1 #ifndef _ASM_WORD_AT_A_TIME_H
   2 #define _ASM_WORD_AT_A_TIME_H
   3
   4 /*
   5  * Word-at-a-time interfaces for PowerPC.
   6  */
   7
   8 #include <linux/kernel.h>
   9 #include <asm/asm-compat.h>
  10
  11 struct word_at_a_time {
  12         const unsigned long high_bits, low_bits;
  13 };
  14
  15 #define WORD_AT_A_TIME_CONSTANTS { REPEAT_BYTE(0xfe) + 1, REPEAT_BYTE(0x7f) }
  16
  17 /* Bit set in the bytes that have a zero */
  18 static inline long prep_zero_mask(unsigned long val, unsigned long rhs, const struct word_at_a_time *c)
  19 {
  20         unsigned long mask = (val & c->low_bits) + c->low_bits;
  21         return ~(mask | rhs);
  22 }
  23
  24 #define create_zero_mask(mask) (mask)
  25
  26 static inline long find_zero(unsigned long mask)
  27 {
  28         long leading_zero_bits;
  29
  30         asm (PPC_CNTLZL "%0,%1" : "=r" (leading_zero_bits) : "r" (mask));
  31         return leading_zero_bits >> 3;
  32 }
  33
  34 static inline bool has_zero(unsigned long val, unsigned long *data, const struct word_at_a_time *c)
  35 {
  36         unsigned long rhs = val | c->low_bits;
  37         *data = rhs;
  38         return (val + c->high_bits) & ~rhs;
  39 }
  40
  41 #endif /* _ASM_WORD_AT_A_TIME_H */