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Mikael Starvik51533b62005-07-27 11:44:44 -07001#ifndef _ASM_CRIS_ARCH_BITOPS_H
2#define _ASM_CRIS_ARCH_BITOPS_H
3
4/*
5 * Helper functions for the core of the ff[sz] functions. They compute the
6 * number of leading zeroes of a bits-in-byte, byte-in-word and
7 * word-in-dword-swapped number. They differ in that the first function also
8 * inverts all bits in the input.
9 */
10
Adrian Bunkd9b54442005-11-07 00:58:44 -080011static inline unsigned long
Mikael Starvik51533b62005-07-27 11:44:44 -070012cris_swapnwbrlz(unsigned long w)
13{
14 unsigned long res;
15
16 __asm__ __volatile__ ("swapnwbr %0\n\t"
17 "lz %0,%0"
18 : "=r" (res) : "0" (w));
19
20 return res;
21}
22
Adrian Bunkd9b54442005-11-07 00:58:44 -080023static inline unsigned long
Mikael Starvik51533b62005-07-27 11:44:44 -070024cris_swapwbrlz(unsigned long w)
25{
26 unsigned long res;
27
28 __asm__ __volatile__ ("swapwbr %0\n\t"
29 "lz %0,%0"
30 : "=r" (res) : "0" (w));
31
32 return res;
33}
34
35/*
36 * Find First Zero in word. Undefined if no zero exist, so the caller should
37 * check against ~0 first.
38 */
Adrian Bunkd9b54442005-11-07 00:58:44 -080039static inline unsigned long
Mikael Starvik51533b62005-07-27 11:44:44 -070040ffz(unsigned long w)
41{
42 return cris_swapnwbrlz(w);
43}
44
45/*
46 * Find First Set bit in word. Undefined if no 1 exist, so the caller
47 * should check against 0 first.
48 */
Adrian Bunkd9b54442005-11-07 00:58:44 -080049static inline unsigned long
Mikael Starvik51533b62005-07-27 11:44:44 -070050__ffs(unsigned long w)
51{
52 return cris_swapnwbrlz(~w);
53}
54
55/*
56 * Find First Bit that is set.
57 */
Adrian Bunkd9b54442005-11-07 00:58:44 -080058static inline unsigned long
Mikael Starvik51533b62005-07-27 11:44:44 -070059kernel_ffs(unsigned long w)
60{
61 return w ? cris_swapwbrlz (w) + 1 : 0;
62}
63
64#endif /* _ASM_CRIS_ARCH_BITOPS_H */