Re: [PATCH] target/s390x: Fix CC set by CONVERT TO FIXED/LOGICAL

[Richard Henderson]

On 6/28/21 9:32 AM, Ulrich Weigand wrote:
> > Don't clear out env->fpu_status.float_exception_flags in
> > handle_exceptions.  Wait until we're actually done with the data.
>
> I don't really know much about qemu internals, but this is really
> confusing me, sorry.  Aren't env->fpu_status and env->cc_op two
> elements of the same global state?  Why it is OK to use one of
> these fields to pass information to the next helper, but not the
> other?  I guess I must be missing something here ...

One of them has

    cc_op = tcg_global_mem_new_i32(cpu_env, offsetof(CPUS390XState, cc_op),
                                   "cc_op");

which makes it a TCG Global, which may not be modified at will, and one of them 
does not.


r~