Re: [RFC PATCH v4 2/5] target/riscv: rvv: Provide a fast path using direct access to host ram for unmasked unit-stride load/store

[Richard Henderson]

On 6/13/24 10:51, Max Chou wrote:
> +#define GEN_VEXT_LD_ELEM(NAME, ETYPE, H, LDSUF)                         \
> +static void NAME##_tlb(CPURISCVState *env, abi_ptr addr,                \
> +                       uint32_t byte_off, void *vd, uintptr_t retaddr)  \
> +{                                                                       \
> +    uint8_t *reg = ((uint8_t *)vd + byte_off);                          \
> +    ETYPE *cur = ((ETYPE *)reg);                                        \
> +    *cur = cpu_##LDSUF##_data_ra(env, addr, retaddr);                   \
> +}                                                                       \
> +                                                                        \
> +static void NAME##_host(void *vd, uint32_t byte_off, void *host)        \
> +{                                                                       \
> +    ETYPE val = LDSUF##_p(host);                                        \
> +    uint8_t *reg = (uint8_t *)(vd + byte_off);                          \
> +    *(ETYPE *)(reg) = val;                                              \
> +}

Why are you casting to and from uint8_t* ?

Surely this is cleaner as

    ETYPE *cur = vd + byte_off;


r~