On Mon, 3 Feb 2020 at 14:47, Richard Henderson
<richard.henderson@linaro.org> wrote:
>
> Split this helper out of msr_mask in translate.c. At the same time,
> transform the negative reductive logic to positive accumulative logic.
> It will be usable along the exception paths.
>
> Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
> ---
> target/arm/internals.h | 24 ++++++++++++++++++++++++
> target/arm/translate.c | 17 +++--------------
> 2 files changed, 27 insertions(+), 14 deletions(-)
>
> diff --git a/target/arm/internals.h b/target/arm/internals.h
> index 6be8b2d1a9..0569c96fd9 100644
> --- a/target/arm/internals.h
> +++ b/target/arm/internals.h
> @@ -1061,6 +1061,30 @@ static inline bool arm_mmu_idx_is_stage1_of_2(ARMMMUIdx mmu_idx)
> }
> }
>
> +static inline uint32_t aarch32_cpsr_valid_mask(uint64_t features,
> + const ARMISARegisters *id)
> +{
> + uint32_t valid = CPSR_M | CPSR_AIF | CPSR_IL | CPSR_NZCV;
> +
> + if ((features >> ARM_FEATURE_V4T) & 1) {
> + valid |= CPSR_T;
> + }
> + if ((features >> ARM_FEATURE_V5) & 1) {
> + valid |= CPSR_Q; /* V5TE in reality*/
> + }
> + if ((features >> ARM_FEATURE_V6) & 1) {
> + valid |= CPSR_E | CPSR_GE;
> + }
> + if ((features >> ARM_FEATURE_THUMB2) & 1) {
> + valid |= CPSR_IT;
> + }
> + if (isar_feature_jazelle(id)) {
> + valid |= CPSR_J;
> + }
This is a behaviour-change rather than just refactoring:
we used to unconditionally allow the J bit through,
and now we only do so if the isar feature bit is set.
> + return valid;
> +}
> +
> /*
> * Parameters of a given virtual address, as extracted from the
> * translation control register (TCR) for a given regime.
> diff --git a/target/arm/translate.c b/target/arm/translate.c
> index d58c328e08..032f7074cb 100644
> --- a/target/arm/translate.c
> +++ b/target/arm/translate.c
> @@ -2747,22 +2747,11 @@ static uint32_t msr_mask(DisasContext *s, int flags, int spsr)
> mask |= 0xff000000;
>
> /* Mask out undefined bits. */
> - mask &= ~CPSR_RESERVED;
> - if (!arm_dc_feature(s, ARM_FEATURE_V4T)) {
> - mask &= ~CPSR_T;
> - }
> - if (!arm_dc_feature(s, ARM_FEATURE_V5)) {
> - mask &= ~CPSR_Q; /* V5TE in reality*/
> - }
> - if (!arm_dc_feature(s, ARM_FEATURE_V6)) {
> - mask &= ~(CPSR_E | CPSR_GE);
> - }
> - if (!arm_dc_feature(s, ARM_FEATURE_THUMB2)) {
> - mask &= ~CPSR_IT;
> - }
> + mask &= aarch32_cpsr_valid_mask(s->features, s->isar);
> +
> /* Mask out execution state and reserved bits. */
This comment no longer matches the code it's referring to.
> if (!spsr) {
> - mask &= ~(CPSR_EXEC | CPSR_RESERVED);
> + mask &= ~CPSR_EXEC;
> }
> /* Mask out privileged bits. */
> if (IS_USER(s))
> --
Otherwise
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
thanks
-- PMM