m68hc11 target / S12X / XGATE

m68hc11 target / S12X / XGATE

[James Murray]

(First post on the list)

I have been actively using the m68hc11/12 binutils target for a number
of years with gcc. Over the last few years I have extended the support
for that target to the S12X CPU derivative and added support for
assembling, disassembling and linking for the XGATE co-processor.
While these are two actual CPUs with different machine code I've made
them build as the same elf type so they can be linked and share symbols.
(This seems to work and there are hundreds of cars/bikes driving around
using the generated code.)

The "current" maintainer of the hc11 port Stephane Carrez appears to be
busy elsewhere and the last post I found in the archives here from him
or on hc11 was from over five years ago.

Ideally I would like to contribute my work back to the mainstream of
code, but need guidance first. I have done some searches on the
following, but not seen the answer - so pointers appreciated.

- what is the test process to satisfy that the code is good
- what authorisation process is used to validate my code changes?
- what "indent" commandline should I use on the C files I've altered ?
- anything else?

Until now I've been using a 2.18 derivative, so I presume a first step
would be to apply those changes to a CVS checkout and confirm it all
works locally.

regards

James

Re: m68hc11 target / S12X / XGATE

[Ian Lance Taylor]

James Murray <jsm@jsm-net.demon.co.uk> writes:

> Ideally I would like to contribute my work back to the mainstream of
> code, but need guidance first. I have done some searches on the
> following, but not seen the answer - so pointers appreciated.
>
> - what is the test process to satisfy that the code is good

make check

although it's not very effective as it mostly tests the binutils for
consistency with themselves rather than for consistency with actual
hardware.  Ideally you would also test your binutils using gcc, by
running "make check" in gcc and ensuring that the execution tests pass.
However, I understand in this case that the gcc port is also broken.

Note that the gcc port is on the verge of being deprecated and removed,
so if you want to save it this would be a good time to speak up on
gcc.gnu.org.  See http://gcc.gnu.org/ml/gcc/2011-01/msg00391.html .

> - what authorisation process is used to validate my code changes?

Your changes can not be commited until they are approved by a binutils
maintainer.  The process is to send a patch to binutils@sourceware.org
and to ping the patch more or less weekly until a maintainer approves or
rejects it.

> - what "indent" commandline should I use on the C files I've altered ?

Usually running GNU indent with no options will do approximately the
right thing.

> - anything else?

You need to sign an FSF copyright assignment for your patches to be
accepted into the sources.  I can send you the form to start this
process if you need it.

The gcc contribution guidelines mostly apply to the binutils as well:
http://gcc.gnu.org/contribute.html (although as you know the binutils
still use CVS).

> Until now I've been using a 2.18 derivative, so I presume a first step
> would be to apply those changes to a CVS checkout and confirm it all
> works locally.

Yes.

Ian

Re: m68hc11 target / S12X / XGATE

[James Murray]

OK, thanks for the tips. I'll work on those (assuming make test is
available in gcc-3.3.6)

As noted, I am and will continue to actively test the generated code on
real hardware. It runs my car.

For gcc, this target is working fine with a 3.3.6 derivative, but the
patches never fully made mainstream gcc - so even 3.4.0 is worthless. 

I have made an attempt to forward port to recent gcc releases but got
nowhere in a hurry.

(A colleague of mine is looking at LLVM support instead.)

regards

James