* [PATCH] LoongArch: implement count_{leading,trailing}_zeros
@ 2022-10-12 14:23 Xi Ruoyao
2022-10-13 8:43 ` Lulu Cheng
0 siblings, 1 reply; 3+ messages in thread
From: Xi Ruoyao @ 2022-10-12 14:23 UTC (permalink / raw)
To: gcc-patches; +Cc: Lulu Cheng, Wang Xuerui, Chenghua Xu, Xi Ruoyao
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.
---
include/longlong.h | 12 ++++++++++++
1 file changed, 12 insertions(+)
diff --git a/include/longlong.h b/include/longlong.h
index 64a7b10f9b2..c3a6f1e7eaa 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. */ \
--
2.38.0
^ permalink raw reply [flat|nested] 3+ messages in thread* Re: [PATCH] LoongArch: implement count_{leading,trailing}_zeros
2022-10-12 14:23 [PATCH] LoongArch: implement count_{leading,trailing}_zeros Xi Ruoyao
@ 2022-10-13 8:43 ` Lulu Cheng
2022-10-13 10:06 ` pushed: " Xi Ruoyao
0 siblings, 1 reply; 3+ messages in thread
From: Lulu Cheng @ 2022-10-13 8:43 UTC (permalink / raw)
To: Xi Ruoyao, gcc-patches; +Cc: Wang Xuerui, Chenghua Xu
Looks good to me!
Thanks!
在 2022/10/12 下午10:23, Xi Ruoyao 写道:
> 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.
> ---
> include/longlong.h | 12 ++++++++++++
> 1 file changed, 12 insertions(+)
>
> diff --git a/include/longlong.h b/include/longlong.h
> index 64a7b10f9b2..c3a6f1e7eaa 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. */ \
^ permalink raw reply [flat|nested] 3+ messages in thread* pushed: [PATCH] LoongArch: implement count_{leading,trailing}_zeros
2022-10-13 8:43 ` Lulu Cheng
@ 2022-10-13 10:06 ` Xi Ruoyao
0 siblings, 0 replies; 3+ messages in thread
From: Xi Ruoyao @ 2022-10-13 10:06 UTC (permalink / raw)
To: Lulu Cheng, gcc-patches; +Cc: Wang Xuerui, Chenghua Xu
On Thu, 2022-10-13 at 16:43 +0800, Lulu Cheng wrote:
> Looks good to me!
>
> Thanks!
Pushed r13-3269.
>
> 在 2022/10/12 下午10:23, Xi Ruoyao 写道:
> > 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.
> > ---
> > include/longlong.h | 12 ++++++++++++
> > 1 file changed, 12 insertions(+)
> >
> > diff --git a/include/longlong.h b/include/longlong.h
> > index 64a7b10f9b2..c3a6f1e7eaa 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. */ \
>
--
Xi Ruoyao <xry111@xry111.site>
School of Aerospace Science and Technology, Xidian University
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2022-10-12 14:23 [PATCH] LoongArch: implement count_{leading,trailing}_zeros Xi Ruoyao
2022-10-13 8:43 ` Lulu Cheng
2022-10-13 10:06 ` pushed: " Xi Ruoyao
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