Re: [PATCH v4 3/4] add rvv memcpy in ifunc-impl-list

[Adhemerval Zanella Netto <adhemerval.zanella@linaro.org>]

On 21/01/25 23:04, daichengrong@iscas.ac.cn wrote:
> From: daichengrong <daichengrong@iscas.ac.cn>

This patch should be squashed with the last one, otherwise this will break
glibc build.

> 
> ---
>  .../unix/sysv/linux/riscv/multiarch/ifunc-impl-list.c    | 9 +++++++++
>  1 file changed, 9 insertions(+)
> 
> diff --git a/sysdeps/unix/sysv/linux/riscv/multiarch/ifunc-impl-list.c b/sysdeps/unix/sysv/linux/riscv/multiarch/ifunc-impl-list.c
> index 1c1deca8f6..01846a7414 100644
> --- a/sysdeps/unix/sysv/linux/riscv/multiarch/ifunc-impl-list.c
> +++ b/sysdeps/unix/sysv/linux/riscv/multiarch/ifunc-impl-list.c
> @@ -27,6 +27,7 @@ __libc_ifunc_impl_list (const char *name, struct libc_ifunc_impl *array,
>    size_t i = max;
>  
>    bool fast_unaligned = false;
> +  bool rvv_ext = false;
>  
>    struct riscv_hwprobe pair = { .key = RISCV_HWPROBE_KEY_CPUPERF_0 };
>    if (__riscv_hwprobe (&pair, 1, 0, NULL, 0) == 0
> @@ -34,7 +35,15 @@ __libc_ifunc_impl_list (const char *name, struct libc_ifunc_impl *array,
>            == RISCV_HWPROBE_MISALIGNED_FAST)
>      fast_unaligned = true;
>  
> +  pair.key = RISCV_HWPROBE_KEY_IMA_EXT_0;
> +  pair.value = 0;
> +  if (__riscv_hwprobe (&pair, 1, 0, NULL, 0) == 0
> +      && (pair.value & RISCV_HWPROBE_IMA_V) == RISCV_HWPROBE_IMA_V)
> +    rvv_ext = true;

Maybe issue only one __riscv_hwprobe? Afaiu its idea is to allow query multiple
hardware support with only one call.

> +
>    IFUNC_IMPL (i, name, memcpy,
> +	      IFUNC_IMPL_ADD (array, i, memcpy, rvv_ext,
> +			      __memcpy_vector)
>  	      IFUNC_IMPL_ADD (array, i, memcpy, fast_unaligned,
>  			      __memcpy_noalignment)
>  	      IFUNC_IMPL_ADD (array, i, memcpy, 1, __memcpy_generic))