Re: [qemu-s390x] [Qemu-devel] [PATCH v2 02/28] s390x/tcg: MVCL: Zero out unused bits of address

[David Hildenbrand]

On 11.09.19 16:40, Richard Henderson wrote:
> On 9/6/19 3:57 AM, David Hildenbrand wrote:
>> We have to zero out unused bits in 24 and 31-bit addressing mode.
>> Provide a new helper.
>>
>> Signed-off-by: David Hildenbrand <address@hidden>
>> ---
>>  target/s390x/mem_helper.c | 24 ++++++++++++++++++++++--
>>  1 file changed, 22 insertions(+), 2 deletions(-)
> 
> Reviewed-by: Richard Henderson <address@hidden>
> 
> 
>> diff --git a/target/s390x/mem_helper.c b/target/s390x/mem_helper.c
>> index 39ee9b3175..3152bdafe2 100644
>> --- a/target/s390x/mem_helper.c
>> +++ b/target/s390x/mem_helper.c
>> @@ -469,6 +469,26 @@ static inline uint64_t get_address(CPUS390XState *env, 
>> int reg)
>>      return wrap_address(env, env->regs[reg]);
>>  }
>>  
>> +/*
>> + * Store the address to the given register, zeroing out unused leftmost
>> + * bits in bit positions 32-63 (24-bit and 31-bit mode only).
>> + */
>> +static inline void set_address_zero(CPUS390XState *env, int reg,
>> +                                    uint64_t address)
>> +{
>> +    if (env->psw.mask & PSW_MASK_64) {
>> +        env->regs[reg] = address;
>> +    } else {
>> +        if (!(env->psw.mask & PSW_MASK_32)) {
>> +            address &= 0x00ffffff;
>> +            env->regs[reg] = deposit64(env->regs[reg], 0, 32, address);
>> +        } else {
>> +            address &= 0x7fffffff;
>> +            env->regs[reg] = deposit64(env->regs[reg], 0, 32, address);
>> +        }
> 
> You could perhaps sink the deposit and store line into the outer else.
> 

Thanks, will do!


-- 

Thanks,

David / dhildenb