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| author | Xi Ruoyao <xry111@xry111.site> | 2022-10-12 22:06:07 +0800 |
|---|---|---|
| committer | Xi Ruoyao <xry111@xry111.site> | 2022-10-13 18:05:22 +0800 |
| commit | 6f653a2c85a450714bac905ea4f153234bc6cd5f (patch) | |
| tree | d6218ef805fa751f65760f726dbf7b77bbfbe3cf /include | |
| parent | 7f9a7465c863e482708d2a00f5f7ff91ae3a7e0b (diff) | |
| download | gcc-6f653a2c85a450714bac905ea4f153234bc6cd5f.zip gcc-6f653a2c85a450714bac905ea4f153234bc6cd5f.tar.gz gcc-6f653a2c85a450714bac905ea4f153234bc6cd5f.tar.bz2 | |
LoongArch: implement count_{leading,trailing}_zeros
LoongArch always support clz and ctz instructions, so we can always use
__builtin_{clz,ctz} for count_{leading,trailing}_zeros. This improves
the code of libgcc, and also benefits Glibc once we merge longlong.h
there.
Bootstrapped and regtested on loongarch64-linux-gnu.
include/ChangeLog:
* longlong.h [__loongarch__] (count_leading_zeros): Define.
[__loongarch__] (count_trailing_zeros): Likewise.
[__loongarch__] (COUNT_LEADING_ZEROS_0): Likewise.
Diffstat (limited to 'include')
| -rw-r--r-- | include/longlong.h | 12 |
1 files changed, 12 insertions, 0 deletions
diff --git a/include/longlong.h b/include/longlong.h index 64a7b10..c3a6f1e 100644 --- a/include/longlong.h +++ b/include/longlong.h @@ -593,6 +593,18 @@ extern UDItype __umulsidi3 (USItype, USItype); #define UMUL_TIME 14 #endif +#ifdef __loongarch__ +# if W_TYPE_SIZE == 32 +# define count_leading_zeros(count, x) ((count) = __builtin_clz (x)) +# define count_trailing_zeros(count, x) ((count) = __builtin_ctz (x)) +# define COUNT_LEADING_ZEROS_0 32 +# elif W_TYPE_SIZE == 64 +# define count_leading_zeros(count, x) ((count) = __builtin_clzll (x)) +# define count_trailing_zeros(count, x) ((count) = __builtin_ctzll (x)) +# define COUNT_LEADING_ZEROS_0 64 +# endif +#endif + #if defined (__M32R__) && W_TYPE_SIZE == 32 #define add_ssaaaa(sh, sl, ah, al, bh, bl) \ /* The cmp clears the condition bit. */ \ |