On 9/24/19 11:00 PM, Alex Bennée wrote:
> From: Richard Henderson <richard.henderson@linaro.org>
>
> The CONFIG_USER_ONLY adjustment blindly mashed the swcr
> exception enable bits into the fpcr exception disable bits.
>
> However, fpcr_exc_enable has already converted the exception
> disable bits into the exception status bits in order to make
> it easier to mask status bits at runtime.
>
> Instead, merge the swcr enable bits with the fpcr before we
> convert to status bits.
>
> Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
> Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
> Message-Id: <20190921043256.4575-4-richard.henderson@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
> ---
> target/alpha/helper.c | 23 ++++++++++++++---------
> 1 file changed, 14 insertions(+), 9 deletions(-)
>
> diff --git a/target/alpha/helper.c b/target/alpha/helper.c
> index 10602fb3394..e21c488aa32 100644
> --- a/target/alpha/helper.c
> +++ b/target/alpha/helper.c
> @@ -46,34 +46,39 @@ void cpu_alpha_store_fpcr(CPUAlphaState *env, uint64_t val)
> uint32_t fpcr = val >> 32;
> uint32_t t = 0;
>
> + /* Record the raw value before adjusting for linux-user. */
> + env->fpcr = fpcr;
> +
> +#ifdef CONFIG_USER_ONLY
> + /*
> + * Override some of these bits with the contents of ENV->SWCR.
> + * In system mode, some of these would trap to the kernel, at
> + * which point the kernel's handler would emulate and apply
> + * the software exception mask.
> + */
> + uint32_t soft_fpcr = alpha_ieee_swcr_to_fpcr(env->swcr) >> 32;
> + fpcr |= soft_fpcr & FPCR_STATUS_MASK;
> +#endif
> +
> t |= CONVERT_BIT(fpcr, FPCR_INED, FPCR_INE);
> t |= CONVERT_BIT(fpcr, FPCR_UNFD, FPCR_UNF);
> t |= CONVERT_BIT(fpcr, FPCR_OVFD, FPCR_OVF);
> t |= CONVERT_BIT(fpcr, FPCR_DZED, FPCR_DZE);
> t |= CONVERT_BIT(fpcr, FPCR_INVD, FPCR_INV);
>
> - env->fpcr = fpcr;
> env->fpcr_exc_enable = ~t & FPCR_STATUS_MASK;
>
> env->fpcr_dyn_round = rm_map[(fpcr & FPCR_DYN_MASK) >> FPCR_DYN_SHIFT];
>
> env->fpcr_flush_to_zero = (fpcr & FPCR_UNFD) && (fpcr & FPCR_UNDZ);
> env->fp_status.flush_inputs_to_zero = (fpcr & FPCR_DNZ) != 0;
> -
> #ifdef CONFIG_USER_ONLY
> - /*
> - * Override some of these bits with the contents of ENV->SWCR.
> - * In system mode, some of these would trap to the kernel, at
> - * which point the kernel's handler would emulate and apply
> - * the software exception mask.
> - */
> if (env->swcr & SWCR_MAP_DMZ) {
> env->fp_status.flush_inputs_to_zero = 1;
> }
> if (env->swcr & SWCR_MAP_UMZ) {
> env->fpcr_flush_to_zero = 1;
> }
> - env->fpcr_exc_enable &= ~(alpha_ieee_swcr_to_fpcr(env->swcr) >> 32);
> #endif
> }
>
>