b.liu | e958203 | 2025-04-17 19:18:16 +0800 | [diff] [blame^] | 1 | /* SPDX-License-Identifier: GPL-2.0 */ |
| 2 | #ifndef __ASM_SH_WORD_AT_A_TIME_H |
| 3 | #define __ASM_SH_WORD_AT_A_TIME_H |
| 4 | |
| 5 | #ifdef CONFIG_CPU_BIG_ENDIAN |
| 6 | # include <asm-generic/word-at-a-time.h> |
| 7 | #else |
| 8 | /* |
| 9 | * Little-endian version cribbed from x86. |
| 10 | */ |
| 11 | struct word_at_a_time { |
| 12 | const unsigned long one_bits, high_bits; |
| 13 | }; |
| 14 | |
| 15 | #define WORD_AT_A_TIME_CONSTANTS { REPEAT_BYTE(0x01), REPEAT_BYTE(0x80) } |
| 16 | |
| 17 | /* Carl Chatfield / Jan Achrenius G+ version for 32-bit */ |
| 18 | static inline long count_masked_bytes(long mask) |
| 19 | { |
| 20 | /* (000000 0000ff 00ffff ffffff) -> ( 1 1 2 3 ) */ |
| 21 | long a = (0x0ff0001+mask) >> 23; |
| 22 | /* Fix the 1 for 00 case */ |
| 23 | return a & mask; |
| 24 | } |
| 25 | |
| 26 | /* Return nonzero if it has a zero */ |
| 27 | static inline unsigned long has_zero(unsigned long a, unsigned long *bits, const struct word_at_a_time *c) |
| 28 | { |
| 29 | unsigned long mask = ((a - c->one_bits) & ~a) & c->high_bits; |
| 30 | *bits = mask; |
| 31 | return mask; |
| 32 | } |
| 33 | |
| 34 | static inline unsigned long prep_zero_mask(unsigned long a, unsigned long bits, const struct word_at_a_time *c) |
| 35 | { |
| 36 | return bits; |
| 37 | } |
| 38 | |
| 39 | static inline unsigned long create_zero_mask(unsigned long bits) |
| 40 | { |
| 41 | bits = (bits - 1) & ~bits; |
| 42 | return bits >> 7; |
| 43 | } |
| 44 | |
| 45 | /* The mask we created is directly usable as a bytemask */ |
| 46 | #define zero_bytemask(mask) (mask) |
| 47 | |
| 48 | static inline unsigned long find_zero(unsigned long mask) |
| 49 | { |
| 50 | return count_masked_bytes(mask); |
| 51 | } |
| 52 | #endif |
| 53 | |
| 54 | #endif |