Re: Guile and ucontext

[Fredrik Tolf]

On Sat, 2009-05-16 at 13:07 +0100, Neil Jerram wrote:
> 1. On ia64, Guile's exception and continuation logic is already
> implemented using setcontext() and getcontext().  (This is done via
> some strange redefinitions of setjmp and longjmp; see __scm.h.)  If
> you follow through that code, and the things like stack saving and
> copying that are done in conjunction with those calls, it may give you
> a clear idea of what would be needed to support more general ucontext
> switching.

Indeed? I'll look into that. Thank you!

> >>From what I can tell from Guile's threads.c, Guile will just record the
> > top and bottom of a single stack per pthread, and since I'm switching
> > stack pointer between the original stack at the top of the process to
> > heap-allocated stacks, it would try to mark data words from almost the
> > entire process space when GC'ing.
> 
> I'm afraid I don't understand this.  Are you changing the whole stack
> of an existing thread?

Well, yes. It is hard for me to think of how I would switch contexts
without switching stacks as well. :)

Fredrik Tolf