On Thu, Jan 17, 2002 at 04:07:23PM -0800, Ulrich Drepper wrote: > The time is near when we (well, I) well start a drastic move toward > generally using thread registers. Even in non-threaded code. > > This means that unless all architectures get thread registers (or > equivalent things like Alpha's special code) we'll have a two class > society of platforms where all code written for the platforms without > thread register can be run on the other systems, but not vice versa. > > >From what I see today we have thread registers only on Alpha, x86, > IA-64, SH, and x86_64. SPARC shouldn't be too much of a problem. Sun > is using %g6 or %g7 (forgot which one) and since they define the ABI > no big complications are expected. > > Now, what is about the rest? I assume cris isn't much of a problem > since it's a purely embedded machine. > > > Arm: don't know whether this should fall in the same category. > Philip? > > > m68k: Well, maybe it's time to retire these machines. But on the > other hand, there are those useless address registers. Andreas, Jes? > > > PPC (32-bit) is known to be a problem. I've seen several proposals as > to what register to use but haven't seen a final decision. Problems > with the different PPC implementations are probably hindering this. > Geoff, could you please make a decision? I hope the PPC64 ABI already > allocated a thread register. > > > S390: I have no idea. Martin, please comment and make a decision. > > > MIPS: Who feels responsible? Andreas, HJ? > I don't see there are any registers we can use without breaking ABI. On the other hand, can we change the mips kernel to save k0 or k1 for user space? > > PA: no idea. HP has no 32-bit ELF so. But they have 64-bit ELF and > it definitely has a thread register. > > > > Please consider this a high priority task now. I've been warning > about this for a long time. Jakub is working on some code and once > this is ready for me to use I'll make lots of changes to ld.so and the > locale handling and from that point on we have the two classes of > architectures. > > Oh, this now also concerns Hurd. So, Roland, how far is using LDTs on > Hurd/x86? > H.J.
