Re: [PATCH] target/arm: Clean up arm_cpu_vq_map_next_smaller asserts

[Richard Henderson]

On 11/15/19 5:06 PM, Andrew Jones wrote:
>>      bitnum = find_last_bit(cpu->sve_vq_map, vq - 1);
>> -    return bitnum == vq - 1 ? 0 : bitnum + 1;
>> +
>> +    /* We always have vq == 1 present in sve_vq_map.  */
> 
> This is true with TCG and 99.9999% likely to be true with KVM...

Eh?  It's required by the spec that 128-bit vectors are always supported.


> Maybe we should just remove this function and put the
> find_last_bit() call and all input/output validation directly in
> sve_zcr_get_valid_len() ?

But that makes sense all on its own, so we don't do quite so much +1/-1 faffing
about.


r~