Re: [RESEND PATCH] target/riscv: fix start byte for vmv<nf>r.v when vstart != 0

[Alistair Francis]

On Wed, Mar 30, 2022 at 12:14 PM Weiwei Li <liweiwei@iscas.ac.cn> wrote:
>
> The spec for vmv<nf>r.v says: 'the instructions operate as if EEW=SEW,
> EMUL = NREG, effective length evl= EMUL * VLEN/SEW.'
>
> So the start byte for vstart != 0 should take sew into account
>
> Signed-off-by: Weiwei Li <liweiwei@iscas.ac.cn>
> Signed-off-by: Junqiang Wang <wangjunqiang@iscas.ac.cn>

Thanks!

Applied to riscv-to-apply.next

Alistair

> ---
>  target/riscv/vector_helper.c | 8 +++++---
>  1 file changed, 5 insertions(+), 3 deletions(-)
>
> diff --git a/target/riscv/vector_helper.c b/target/riscv/vector_helper.c
> index 1d4982ef7f..b5fbdabbb1 100644
> --- a/target/riscv/vector_helper.c
> +++ b/target/riscv/vector_helper.c
> @@ -4890,13 +4890,15 @@ GEN_VEXT_VCOMPRESS_VM(vcompress_vm_d, uint64_t, H8)
>  /* Vector Whole Register Move */
>  void HELPER(vmvr_v)(void *vd, void *vs2, CPURISCVState *env, uint32_t desc)
>  {
> -    /* EEW = 8 */
> +    /* EEW = SEW */
>      uint32_t maxsz = simd_maxsz(desc);
> -    uint32_t i = env->vstart;
> +    uint32_t sewb = 1 << FIELD_EX64(env->vtype, VTYPE, VSEW);
> +    uint32_t startb = env->vstart * sewb;
> +    uint32_t i = startb;
>
>      memcpy((uint8_t *)vd + H1(i),
>             (uint8_t *)vs2 + H1(i),
> -           maxsz - env->vstart);
> +           maxsz - startb);
>
>      env->vstart = 0;
>  }
> --
> 2.17.1
>
>