On Wed, 6 Feb 2008, Eric Botcazou wrote:
> > I'm not sure what to do about bit-aligned TImode fields
> > for example, or other things that appearantly can be done with Ada
> > (which allows bit-packing).
>
> I think that we can live without TImode bitfields, up to DImode would be fine.
I was mainly worried about us trying to for example copy a bit-packed
substructure like
struct A {
unsigned use_1_bit : 1;
struct B {
char large[100];
} b;
} a, b;
where b.large[0] is at offset 1 bit of a (I believe this is possible
with Ada, right?). If we then have the IL (no idea if we would
consider this valid, but this is before GIMPLE):
a.b = b.b;
I have no idea how to best lower this ;) Basically, I want to be
able to load/store an aligned unit covering the bitfield into a
register.
But I guess we'll see when it actually happens.
Richard.
