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

   1 /* SPDX-License-Identifier: GPL-2.0-only */
   2 /*
   3  * Copyright (C) 2012 Regents of the University of California
   4  *
   5  * Derived from arch/x86/include/asm/word-at-a-time.h
   6  */
   7
   8 #ifndef _ASM_RISCV_WORD_AT_A_TIME_H
   9 #define _ASM_RISCV_WORD_AT_A_TIME_H
  10
  11
  12 #include <linux/kernel.h>
  13
  14 struct word_at_a_time {
  15         const unsigned long one_bits, high_bits;
  16 };
  17
  18 #define WORD_AT_A_TIME_CONSTANTS { REPEAT_BYTE(0x01), REPEAT_BYTE(0x80) }
  19
  20 static inline unsigned long has_zero(unsigned long val,
  21         unsigned long *bits, const struct word_at_a_time *c)
  22 {
  23         unsigned long mask = ((val - c->one_bits) & ~val) & c->high_bits;
  24         *bits = mask;
  25         return mask;
  26 }
  27
  28 static inline unsigned long prep_zero_mask(unsigned long val,
  29         unsigned long bits, const struct word_at_a_time *c)
  30 {
  31         return bits;
  32 }
  33
  34 static inline unsigned long create_zero_mask(unsigned long bits)
  35 {
  36         bits = (bits - 1) & ~bits;
  37         return bits >> 7;
  38 }
  39
  40 static inline unsigned long find_zero(unsigned long mask)
  41 {
  42         return fls64(mask) >> 3;
  43 }
  44
  45 /* The mask we created is directly usable as a bytemask */
  46 #define zero_bytemask(mask) (mask)
  47
  48 #endif /* _ASM_RISCV_WORD_AT_A_TIME_H */