Re: [Qemu-arm] [Qemu-devel] [PATCH v2 05/32] target/arm/cpu.h: add additional float_status flags

[Richard Henderson]

On 02/08/2018 09:31 AM, Alex Bennée wrote:
> @@ -10750,15 +10751,22 @@ void HELPER(vfp_set_fpscr)(CPUARMState *env, 
> uint32_t val)
>          }
>          set_float_rounding_mode(i, &env->vfp.fp_status);
>      }
> -    if (changed & (1 << 24)) {
> +    if (changed & (1 << 19)) { /* FPCR:FZ16 */
> +        set_flush_to_zero((val & (1 << 19)) != 0, &env->vfp.fp_status_f16);
> +        set_flush_inputs_to_zero((val & (1 << 19)) != 0,
> +                                 &env->vfp.fp_status_f16);
> +    }
> +    if (changed & (1 << 24)) { /* FPCR:FZ */
>          set_flush_to_zero((val & (1 << 24)) != 0, &env->vfp.fp_status);
>          set_flush_inputs_to_zero((val & (1 << 24)) != 0, 
> &env->vfp.fp_status);
>      }
> -    if (changed & (1 << 25))
> +    if (changed & (1 << 25)) { /* FPCR:DN */
>          set_default_nan_mode((val & (1 << 25)) != 0, &env->vfp.fp_status);
> +    }

This misses changing rounding mode and default_nan_mode for fp_status_f16.

>      set_float_exception_flags(i, &env->vfp.fp_status);
> +    set_float_exception_flags(i, &env->vfp.fp_status_f16);
>      set_float_exception_flags(0, &env->vfp.standard_fp_status);

I think you should store 0 into fp_status_f16 here.  The exception flags are
OR'ed together when reading; there's not too much point in replicating it out.


r~