PowerPC64 TLS ABI

[Alan Modra]

On Sat, Jan 18, 2003 at 10:52:34AM +0100, Jakub Jelinek wrote:
> Well, you could have _pthread_descr at the negative offsets from the TP
> and have more than 32K of quickly accessable TLS data too:
> if the ABI says that says that r13[-0x7000] is the DTV pointer,
> then you have 60K-sizeof(tcbhead_t) big "fast" TLS area and
> those 4K should be enough for the thread implementation to
> have some of its most important data stored there (well, for linuxthreads
> or NPTL the whole thread structure would easily fit).

I think I'll settle for r13 - 0x7000 at the _end_ of the TCB.  That
way the toolchain won't have to know about the size of the TCB when
deciding whether a particular addressing scheme works for a given
offset.  Knowledge about the TCB and any other thread structures can
stay nicely in glibc.

-- 
Alan Modra
IBM OzLabs - Linux Technology Centre