[Gcl-devel] Re: gcc-3.3 bugs Debian unstable hppa

[Carlos O'Donell]

On Mon, Mar 08, 2004 at 07:27:59AM -0500, Camm Maguire wrote:
> Greetings!  GCL can mark the C stack via a simple heuristic algorithm
> given its bottom (taken at program start) and top (at point of GBC
> marking).  It cannot mark items in registers, so it must flush the
> registers to the C stack first.  This is typically done with setjmp,
> but for some reason this wasn't working on hppa.   Are we catching all
> the regs in the code below?

I don't see why the setjmp code wouldn't work. Here you just replace the
setjmp buffer with a 'struct regs' and call some assembly that writes
the same thing into the structure.

What registers are you interested in saving? If you make a function call
later, you are probably interested in saving the caller saves registers,
since the others must be retsored by the called function. Please clarify
this.

Lastly, how do you account for the fact that hppa's stack grows up, and
the difference between top and bottom is negative? I've had to cleanup a
lot of code in glibc that made the wrong assumptions.

c.