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| author | Adhemerval Zanella Netto <adhemerval.zanella@linaro.org> | 2023-08-25 13:30:58 -0300 |
|---|---|---|
| committer | Adhemerval Zanella <adhemerval.zanella@linaro.org> | 2024-02-01 09:31:33 -0300 |
| commit | ae4b8d6a0e0dc502e3d8307474a2e5691b7434da (patch) | |
| tree | 8e8d958ebb90b9edec3847a53364edb32a2314a3 /string/ffs.c | |
| parent | 26d01172f5c3f3b912ecf21ebb911eb5351bba4d (diff) | |
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string: Use builtins for ffs and ffsll
It allows to remove a lot of arch-specific implementations.
Checked on x86_64, aarch64, powerpc64.
Reviewed-by: Carlos O'Donell <carlos@redhat.com>
Diffstat (limited to 'string/ffs.c')
| -rw-r--r-- | string/ffs.c | 6 |
1 files changed, 5 insertions, 1 deletions
diff --git a/string/ffs.c b/string/ffs.c index 6a05ef8386..760c2bdd8d 100644 --- a/string/ffs.c +++ b/string/ffs.c @@ -18,13 +18,16 @@ #include <limits.h> #define ffsl __something_else #include <string.h> - #undef ffs +#include <math-use-builtins.h> /* Find the first bit set in I. */ int __ffs (int i) { +#if USE_FFS_BUILTIN + return __builtin_ffs (i); +#else static const unsigned char table[] = { 0,1,2,2,3,3,3,3,4,4,4,4,4,4,4,4,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5, @@ -42,6 +45,7 @@ __ffs (int i) a = x <= 0xffff ? (x <= 0xff ? 0 : 8) : (x <= 0xffffff ? 16 : 24); return table[x >> a] + a; +#endif } weak_alias (__ffs, ffs) libc_hidden_def (__ffs) |