RE: [PATCH 07/16] gdb: convert type instance flags to bitfields

AMD General

On Tuesday, July 21, 2026 9:14 PM, Tom Tromey wrote:
> >>>>> Tankut Baris Aktemur <[email protected]> writes:
>
> > Convert the instance flags of a type to a struct with bitfields.  This
> > helps avoid bitwise operations and instead refer to the fields by
> > name.  In particular, Harvard address space information (i.e. code
> > space and data space) and address class information become enum values
> > instead of being handled by seemingly independent bits.
>
> Thanks.
>
> I like this direction.  I have a couple minor questions.
>
> > +  type_instance_flags &operator|= (const type_instance_flags &other)
> > +  {
> ...
> > +    harvard_aspace
> > +      = static_cast<harvard_address_space> (harvard_aspace
> > +                                         | other.harvard_aspace);
> > +    address_class = address_class | other.address_class;
>
> These two assignments in particular don't really make sense to me.
> Perhaps they should assert that the relevant member of 'this' is 0?

I agree.  I updated the patch accordingly.  Thanks for catching this.

> > @@ -1593,7 +1616,7 @@ struct type
> >       instance flags are completely inherited from the target type.  No
> >       qualifiers can be cleared by the typedef.  See also
> >       check_typedef.  */
> > -  unsigned m_instance_flags : 9;
> > +  type_instance_flags m_instance_flags;
>
> I would guess this increases the size of 'struct type'.
> I don't think it's a big deal, but I'm curious about it.

Checking with sizeof, both before and after the change, the size of a type
object is 56.

-Baris