On Wed, 14 Jun 2006 12:50:40 -0400, Daniel Jacobowitz <dan@xxxxxxxxxx> wrote:
> > For example, in the code below, RDHWR is placed _before_ checking the
> > error. I suppose these instructions were reordered by gcc's
> > optimization, but the optimization would have large negative effect in
> > this case.
>
> You'd have to figure out how to get GCC not to eagerly schedule the
> rdhwr. This might be quite hard. I don't know much about this part of
> the scheduler.
I really did not understand yet how errno is bound TLS. I found some
"rdhwr" in glibc-ports source code (tls-macros.h, nptl/tls.h). The
RDHWR instruction in the example code comes from one of them, no?
I also found a "rdhwr" in gcc's mips.md file ("tls_get_tp_<mode>").
Is this the origin? MD is a very foreign language for me...
---
Atsushi Nemoto
