diff options
Diffstat (limited to 'arch/riscv/include/asm/word-at-a-time.h')
-rw-r--r-- | arch/riscv/include/asm/word-at-a-time.h | 55 |
1 files changed, 55 insertions, 0 deletions
diff --git a/arch/riscv/include/asm/word-at-a-time.h b/arch/riscv/include/asm/word-at-a-time.h new file mode 100644 index 000000000000..aa6238791d3e --- /dev/null +++ b/arch/riscv/include/asm/word-at-a-time.h @@ -0,0 +1,55 @@ +/* + * Copyright (C) 2012 Regents of the University of California + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License + * as published by the Free Software Foundation, version 2. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * Derived from arch/x86/include/asm/word-at-a-time.h + */ + +#ifndef _ASM_RISCV_WORD_AT_A_TIME_H +#define _ASM_RISCV_WORD_AT_A_TIME_H + + +#include <linux/kernel.h> + +struct word_at_a_time { + const unsigned long one_bits, high_bits; +}; + +#define WORD_AT_A_TIME_CONSTANTS { REPEAT_BYTE(0x01), REPEAT_BYTE(0x80) } + +static inline unsigned long has_zero(unsigned long val, + unsigned long *bits, const struct word_at_a_time *c) +{ + unsigned long mask = ((val - c->one_bits) & ~val) & c->high_bits; + *bits = mask; + return mask; +} + +static inline unsigned long prep_zero_mask(unsigned long val, + 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; +} + +static inline unsigned long find_zero(unsigned long mask) +{ + return fls64(mask) >> 3; +} + +/* The mask we created is directly usable as a bytemask */ +#define zero_bytemask(mask) (mask) + +#endif /* _ASM_RISCV_WORD_AT_A_TIME_H */ |