Re: [Qemu-devel] [PATCH] target/s390x: Implement CSST

[Richard Henderson]

On 06/19/2017 01:08 AM, Thomas Huth wrote:
> > +    /* Sanity check the function code and storage characteristic.  */
> > +    if (fc > 1 || sc > 3) {
> > +        if (!s390_has_feat(S390_FEAT_COMPARE_AND_SWAP_AND_STORE_2)) {
> > +            goto spec_exception;
> > +        }
> > +        if (fc > 2 || sc > 4 || (fc == 2 && (r3 & 1))) {
> I think you could omit the "fc == 2" here. fc has to be bigger than 1
> due to the outer if-statement, and if it is not 2, the first "fc > 1"
> has already triggered. So "fc" has to be 2 here and the "fc == 2" is a
> redundant check.

Quite right.


r~