diff options
Diffstat (limited to 'include/asm-xtensa')
| -rw-r--r-- | include/asm-xtensa/bitops.h | 60 |
1 files changed, 26 insertions, 34 deletions
diff --git a/include/asm-xtensa/bitops.h b/include/asm-xtensa/bitops.h index d815649617a..96303dff3ee 100644 --- a/include/asm-xtensa/bitops.h +++ b/include/asm-xtensa/bitops.h @@ -7,7 +7,7 @@ * License. See the file "COPYING" in the main directory of this archive * for more details. * - * Copyright (C) 2001 - 2005 Tensilica Inc. + * Copyright (C) 2001 - 2007 Tensilica Inc. */ #ifndef _XTENSA_BITOPS_H @@ -31,64 +31,44 @@ #if XCHAL_HAVE_NSA -static __inline__ int __cntlz (unsigned long x) +static inline unsigned long __cntlz (unsigned long x) { int lz; asm ("nsau %0, %1" : "=r" (lz) : "r" (x)); - return 31 - lz; + return lz; } -#else - -static __inline__ int __cntlz (unsigned long x) -{ - unsigned long sum, x1, x2, x4, x8, x16; - x1 = x & 0xAAAAAAAA; - x2 = x & 0xCCCCCCCC; - x4 = x & 0xF0F0F0F0; - x8 = x & 0xFF00FF00; - x16 = x & 0xFFFF0000; - sum = x2 ? 2 : 0; - sum += (x16 != 0) * 16; - sum += (x8 != 0) * 8; - sum += (x4 != 0) * 4; - sum += (x1 != 0); - - return sum; -} - -#endif - /* * ffz: Find first zero in word. Undefined if no zero exists. * bit 0 is the LSB of addr; bit 32 is the LSB of (addr+1). */ -static __inline__ int ffz(unsigned long x) +static inline int ffz(unsigned long x) { - if ((x = ~x) == 0) - return 32; - return __cntlz(x & -x); + return 31 - __cntlz(~x & -~x); } /* * __ffs: Find first bit set in word. Return 0 for bit 0 */ -static __inline__ int __ffs(unsigned long x) +static inline int __ffs(unsigned long x) { - return __cntlz(x & -x); + return 31 - __cntlz(x & -x); } + +#ifdef __KERNEL__ + /* * ffs: Find first bit set in word. This is defined the same way as * the libc and compiler builtin ffs routines, therefore * differs in spirit from the above ffz (man ffs). */ -static __inline__ int ffs(unsigned long x) +static inline int ffs(unsigned long x) { - return __cntlz(x & -x) + 1; + return 32 - __cntlz(x & -x); } /* @@ -96,10 +76,22 @@ static __inline__ int ffs(unsigned long x) * Note fls(0) = 0, fls(1) = 1, fls(0x80000000) = 32. */ -static __inline__ int fls (unsigned int x) +static inline int fls (unsigned int x) { - return __cntlz(x); + return 32 - __cntlz(x); } + +#else + +/* Use the generic implementation if we don't have the nsa/nsau instructions. */ + +# include <asm-generic/bitops/ffs.h> +# include <asm-generic/bitops/__ffs.h> +# include <asm-generic/bitops/ffz.h> +# include <asm-generic/bitops/fls.h> + +#endif + #include <asm-generic/bitops/fls64.h> #include <asm-generic/bitops/find.h> #include <asm-generic/bitops/ext2-non-atomic.h> |