On Fri, Aug 10, 2018 at 9:31 PM, Richard Henderson
wrote:
> When FZ is set, input_denormal exceptions are recognized, but this does
> not happen with FZ16. The softfloat code has no way to distinguish
> these bits and will raise such exceptions into fp_status_f16.flags,
> so ignore them when computing the accumulated flags.
>
> Cc: qemu-sta...@nongnu.org (3.0.1)
> Reported-by: Laurent Desnogues
> Signed-off-by: Richard Henderson
Tested-by: Laurent Desnogues
Reviewed-by: Laurent Desnogues
Laurent
> ---
> target/arm/helper.c | 6 +-
> 1 file changed, 5 insertions(+), 1 deletion(-)
>
> diff --git a/target/arm/helper.c b/target/arm/helper.c
> index 452d5e182a..61454a77ec 100644
> --- a/target/arm/helper.c
> +++ b/target/arm/helper.c
> @@ -11314,9 +11314,13 @@ uint32_t HELPER(vfp_get_fpscr)(CPUARMState *env)
> fpscr = (env->vfp.xregs[ARM_VFP_FPSCR] & 0xffc8)
> | (env->vfp.vec_len << 16)
> | (env->vfp.vec_stride << 20);
> +
> i = get_float_exception_flags(>vfp.fp_status);
> i |= get_float_exception_flags(>vfp.standard_fp_status);
> -i |= get_float_exception_flags(>vfp.fp_status_f16);
> +/* FZ16 does not generate an input denormal exception. */
> +i |= (get_float_exception_flags(>vfp.fp_status_f16)
> + & ~float_flag_input_denormal);
> +
> fpscr |= vfp_exceptbits_from_host(i);
> return fpscr;
> }
> --
> 2.17.1
>
