Re: GCJ on mipsel-unknown-linux-gnu

[Andrew Haley <aph at redhat dot com>]

David Daney writes:
 > Andrew Haley wrote:
 > 
 > >Casey Marshall writes:
 > > > Hi. I'm currently trying to get gcj 3.3.3 up and working on
 > > > mipsel-linux, and have gotten pretty far by patching the 3.3.3 release
 > > > with the diffs listed here:
 > > > <http://gcc.gnu.org/ml/gcc-cvs/2003-10/msg00902.html>
 > >
 > >I don't think those patches were for 3.3; I thought they were for
 > >mainline (now 3.5ish.)
 > >
 > > > But I've caught a few snags. My first question is whether or not there
 > > > are any other patches that I should try incorporating besides those in
 > > > the above URL.
 > >
 > >I think David was just about all finished with the MIPS stuff.  I
 > >remember someone (RTH, probably) suggesting a small change to his
 > >MD_FALLBACK_FRAME_STAT_FOR, but that was it.
 > >
 > >  
 > >
 > That is correct.  There are several problems with the current  
 > MD_FALLBACK_FRAME_STATE_FOR.
 > 
 > 1) I think that the current definition of SIGNAL_UNWIND_RETURN_COLUMN 
 > should be changed as I think it currently resides in the slot of a real 
 > register (not sure about this though).

Yeah, I think that's probably true.  I guess it ought not to require a
special column, but i can't remember the MIPS ABI well enough to know.

 > 2) It probably does not do the right thing WRT floating point 
 > registers.  But with respect to libgcj, the signal handler does not use 
 > floating point,so it works.

This all depends on how the MIPS ABI uses floating-point registers.
If they're all callee-saved as they are on some systems, you won't
have a problem.

Andrew.