49 lines
1.1 KiB
C
49 lines
1.1 KiB
C
/* SPDX-License-Identifier: GPL-2.0-only */
|
|
/*
|
|
* Copyright (C) 2012 Regents of the University of California
|
|
*
|
|
* 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 */
|