Re: [PATCH 17/35] target/arm: Always use arm_pan_enabled() when checking if PAN is enabled

[Richard Henderson]

On 12/18/23 22:32, Peter Maydell wrote:
> Currently the code in target/arm/helper.c mostly checks the PAN bits
> in env->pstate or env->uncached_cpsr directly when it wants to know
> if PAN is enabled, because in most callsites we know whether we are
> in AArch64 or AArch32. We do have an arm_pan_enabled() function, but
> we only use it in a few places where the code might run in either an
> AArch32 or AArch64 context.
>
> For FEAT_NV, when HCR_EL2.{NV,NV1} is {1,1} PAN is always disabled
> even when the PSTATE.PAN bit is set, the "is PAN enabled" test
> becomes more complicated. Make all places that check for PAN use
> arm_pan_enabled(), so we have a place to put the FEAT_NV test.
>
> Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
> ---
>   target/arm/helper.c | 22 +++++++++++-----------
>   1 file changed, 11 insertions(+), 11 deletions(-)
>
> diff --git a/target/arm/helper.c b/target/arm/helper.c
> index 3270fb11049..4b0e46cfaae 100644
> --- a/target/arm/helper.c
> +++ b/target/arm/helper.c
> @@ -263,6 +263,15 @@ void init_cpreg_list(ARMCPU *cpu)
>       g_list_free(keys);
>   }
>   
> +static bool arm_pan_enabled(CPUARMState *env)
> +{
> +    if (is_a64(env)) {
> +        return env->pstate & PSTATE_PAN;
> +    } else {
> +        return env->uncached_cpsr & CPSR_PAN;
> +    }
> +}

Worth splitting out helpers aa{32,64}_pan_enabled to avoid the is_a64 check when context 
dictates?

Either way,
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>


r~