diff options
Diffstat (limited to 'sysdeps/i386/i486')
| -rw-r--r-- | sysdeps/i386/i486/bits/string.h | 19 |
1 files changed, 19 insertions, 0 deletions
diff --git a/sysdeps/i386/i486/bits/string.h b/sysdeps/i386/i486/bits/string.h index d4c2eaf715..921c66498e 100644 --- a/sysdeps/i386/i486/bits/string.h +++ b/sysdeps/i386/i486/bits/string.h @@ -1567,6 +1567,25 @@ __strstr_g (__const char *__haystack, __const char *__needle) #endif +/* Bit find functions. We define only the i686 version since for the other + processors gcc generates good code. */ +#if defined __USE_BSD || defined __USE_XOPEN_EXTENDED +# ifdef __i686__ +# define _HAVE_STRING_ARCH_ffs 1 +# define ffs(word) (__builtin_constant_p (word) \ + ? __builtin_ffs (word) \ + : ({ int __cnt, __tmp; \ + __asm__ __volatile__ \ + ("bsfl %2,%0\n\t" \ + "cmovel %1,%0" \ + : "=&r" (__cnt), "=r" (__tmp) \ + : "rm" (word), "1" (-1)); \ + __cnt + 1; })) + +# define ffsl(word) ffs(word) +# endif /* i686 */ +#endif /* BSD || X/Open */ + #undef __STRING_INLINE #endif /* use string inlines && GNU CC */ |