Re: [PATCH v3 01/18] target/s390x: Truncate 32-bit psw_addr before creating TB

[David Hildenbrand]

On 26.09.19 18:25, Richard Henderson wrote:
> If, somehow, the psw_addr is out of range, truncate early
> rather than after we get into gen_intermediate_code.
> 
> Reviewed-by: David Hildenbrand <address@hidden>
> Signed-off-by: Richard Henderson <address@hidden>
> ---
>  target/s390x/cpu.h       | 26 +++++++++++++++++++-------
>  target/s390x/translate.c |  6 ------
>  2 files changed, 19 insertions(+), 13 deletions(-)
> 
> diff --git a/target/s390x/cpu.h b/target/s390x/cpu.h
> index e74a809257..ce20dafd23 100644
> --- a/target/s390x/cpu.h
> +++ b/target/s390x/cpu.h
> @@ -357,18 +357,30 @@ static inline int cpu_mmu_index(CPUS390XState *env, 
> bool ifetch)
>  #endif
>  }
>  
> -static inline void cpu_get_tb_cpu_state(CPUS390XState* env, target_ulong *pc,
> -                                        target_ulong *cs_base, uint32_t 
> *flags)
> +static inline void cpu_get_tb_cpu_state(CPUS390XState* env,
> +                                        target_ulong *p_pc,
> +                                        target_ulong *cs_base,
> +                                        uint32_t *p_flags)
>  {
> -    *pc = env->psw.addr;
> -    *cs_base = env->ex_value;
> -    *flags = (env->psw.mask >> FLAG_MASK_PSW_SHIFT) & FLAG_MASK_PSW;
> +    uint32_t flags;
> +    uint64_t pc;
> +
> +    flags = (env->psw.mask >> FLAG_MASK_PSW_SHIFT) & FLAG_MASK_PSW;
>      if (env->cregs[0] & CR0_AFP) {
> -        *flags |= FLAG_MASK_AFP;
> +        flags |= FLAG_MASK_AFP;
>      }
>      if (env->cregs[0] & CR0_VECTOR) {
> -        *flags |= FLAG_MASK_VECTOR;
> +        flags |= FLAG_MASK_VECTOR;
>      }
> +
> +    pc = env->psw.addr;
> +    if (!(flags & FLAG_MASK_64)) {
> +        pc &= 0x7fffffff;
> +    }

If you're fancy, you could also add 24-bit addressing mode wrapping.

Maybe unlikely(!(flags & FLAG_MASK_64)), but not sure how big the gain
will actually be.

-- 

Thanks,

David / dhildenb