| commit | 2e80f139376450acdb7d879d799439578a41810e | |
| author | Xi Ruoyao <xry111@xry111.site> | |
| Sun, 4 Feb 2024 00:27:50 +0000 (4 08:27 +0800) | ||
| committer | Adhemerval Zanella <adhemerval.zanella@linaro.org> | |
| Mon, 5 Feb 2024 18:19:41 +0000 (5 15:19 -0300) | ||
| tree | 9888c8627c488da707f338232ab4c480c618eba9 | treesnapshot (tar.gz zip) |
| parent | 814ed22eab4f3f43bb02229edab5d50004310258 | commitdiff |
LoongArch: Use builtins for ffs and ffsll
On LoongArch GCC compiles __builtin_ffs{,ll} to basically
`(x ? __builtin_ctz (x) : -1) + 1`. Since a hardware ctz instruction is
available, this is much better than the table-driven generic
implementation.
Tested on loongarch64.
Signed-off-by: Xi Ruoyao <xry111@xry111.site>
Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
On LoongArch GCC compiles __builtin_ffs{,ll} to basically
`(x ? __builtin_ctz (x) : -1) + 1`. Since a hardware ctz instruction is
available, this is much better than the table-driven generic
implementation.
Tested on loongarch64.
Signed-off-by: Xi Ruoyao <xry111@xry111.site>
Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
| sysdeps/loongarch/math-use-builtins-ffs.h | [new file with mode: 0644] | blob |