Re: Debian SuperH port

[David Schleef <ds@schleef.org>]

On Fri, Mar 16, 2001 at 03:31:18AM +0900, YAEGASHI Takeshi wrote:
> Hi there,
> 
> I'm working on Debian SuperH port in Japan, and here are patches for
> dpkg I'm now using.  I wonder if these modifications are acceptable
> for the official release of Debian GNU/Linux.
> 
> With these patches we can have two Debian architectures for SuperH
> family: "sh" is for little endian, "sheb" is for big endian
> configuration.
> 
> In terms of GNU toolchain, there are four different configurations for
> SuperH Linux, namely sh3/sh3eb/sh4/sh4eb.  You must take care not to
> mix up binaries of SH-3 with ones of SH-4.
> 
> However, there is little difference between them except that only the
> latter have FPU instructions, so I think kernel level math emulation
> (not yet implemented) could cope with this problem.

What exactly is involved in math emulation?  I've written one
before for the m68k, and would be willing to do it again if it
is really helpful and needed.  Is there a math library available
for the SH3, i.e., in glibc?  If so, it would be relatively easy
to write the code that handles FPU exceptions and emulates the
instructions.  If not, there are ones available in C, i.e., no
assembly speedups.

Could the additional unsupported instructions be emulated as
well?  I think that decreasing the number of necessary
sub-architectures is a big bonus.





dave...