On Mon, Jan 03, 2011 at 04:48:54PM +0000, Peter Maydell wrote:
> Wire up the new softfloat support for flushing input denormals
> to zero on ARM. The FPSCR FZ bit enables flush-to-zero for
> both inputs and outputs, but the reporting of when inputs are
> flushed to zero is via a separate IDC bit rather than the UFC
> (underflow) bit used when output denormals are flushed to zero.
>
> Signed-off-by: Peter Maydell <peter.mayd...@linaro.org>
> ---
> target-arm/helper.c | 10 ++++++++--
> 1 files changed, 8 insertions(+), 2 deletions(-)
>
> diff --git a/target-arm/helper.c b/target-arm/helper.c
> index 50c1017..705b99f 100644
> --- a/target-arm/helper.c
> +++ b/target-arm/helper.c
> @@ -2242,6 +2242,8 @@ static inline int vfp_exceptbits_from_host(int
> host_bits)
> target_bits |= 8;
> if (host_bits & float_flag_inexact)
> target_bits |= 0x10;
> + if (host_bits & float_flag_input_denormal)
> + target_bits |= 0x80;
> return target_bits;
> }
>
> @@ -2278,6 +2280,8 @@ static inline int vfp_exceptbits_to_host(int
> target_bits)
> host_bits |= float_flag_underflow;
> if (target_bits & 0x10)
> host_bits |= float_flag_inexact;
> + if (target_bits & 0x80)
> + host_bits |= float_flag_input_denormal;
> return host_bits;
> }
>
> @@ -2310,12 +2314,14 @@ void HELPER(vfp_set_fpscr)(CPUState *env, uint32_t
> val)
> }
> set_float_rounding_mode(i, &env->vfp.fp_status);
> }
> - if (changed & (1 << 24))
> + if (changed & (1 << 24)) {
> 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))
> set_default_nan_mode((val & (1 << 25)) != 0, &env->vfp.fp_status);
>
> - i = vfp_exceptbits_to_host((val >> 8) & 0x1f);
> + i = vfp_exceptbits_to_host(val);
This change looks correct (using the flag instead of the enable bit),
but it might be worth mentioning it.
> set_float_exception_flags(i, &env->vfp.fp_status);
> }
Acked-by: Aurelien Jarno <aurel...@aurel32.net>
--
Aurelien Jarno GPG: 1024D/F1BCDB73
aurel...@aurel32.net http://www.aurel32.net
