Re: [RFC PATCH v2 31/44] target/loongarch: Implement vpcnt

[Richard Henderson]

On 3/27/23 20:06, Song Gao wrote:
> +static uint64_t do_vpcnt(uint64_t u1)
> +{
> +    u1 = (u1 & 0x5555555555555555ULL) + ((u1 >>  1) & 0x5555555555555555ULL);
> +    u1 = (u1 & 0x3333333333333333ULL) + ((u1 >>  2) & 0x3333333333333333ULL);
> +    u1 = (u1 & 0x0F0F0F0F0F0F0F0FULL) + ((u1 >>  4) & 0x0F0F0F0F0F0F0F0FULL);
> +    u1 = (u1 & 0x00FF00FF00FF00FFULL) + ((u1 >>  8) & 0x00FF00FF00FF00FFULL);
> +    u1 = (u1 & 0x0000FFFF0000FFFFULL) + ((u1 >> 16) & 0x0000FFFF0000FFFFULL);
> +    u1 = (u1 & 0x00000000FFFFFFFFULL) + ((u1 >> 32));
> +
> +    return u1;
> +}
> +
> +#define VPCNT(NAME, BIT, E, T)                                      \
> +void HELPER(NAME)(CPULoongArchState *env, uint32_t vd, uint32_t vj) \
> +{                                                                   \
> +    int i;                                                          \
> +    VReg *Vd = &(env->fpr[vd].vreg);                                \
> +    VReg *Vj = &(env->fpr[vj].vreg);                                \
> +                                                                    \
> +    for (i = 0; i < LSX_LEN/BIT; i++)                               \
> +    {                                                               \
> +        Vd->E(i) = do_vpcnt((T)Vj->E(i));                           \
> +    }                                                               \
> +}
> +
> +VPCNT(vpcnt_b, 8, B, uint8_t)
> +VPCNT(vpcnt_h, 16, H, uint16_t)
> +VPCNT(vpcnt_w, 32, W, uint32_t)
> +VPCNT(vpcnt_d, 64, D, uint64_t)

host-utils.h has ctpop{8,16,32,64}.


r~