Re: intel 960 support Was: pentium?

Re: intel 960 support Was: pentium?

[Mike Stump]

> Date: Wed, 01 Oct 1997 12:21:11 -0700
> From: Jim Wilson <wilson@cygnus.com>

> There is also the issue of copyright assignments.  We can't use
> Intel's code without a copyright assignment from Intel.  I am not
> sure how hard it will be to get one; it might be easier to just
> write new code from scratch in some cases.

Maybe not that hard...  Below is what's on file already.

GNUC    Intel Corporation       (US)
Assigns changes, including global common subexpression elimination and 387 (tm)support.

GCC     Intel Corp.
Disclaims changes to GCC.

GCC, GDB, GAS, GLD, GSTRIP, GAR, GNM, GSIZE, LIBBFD.A   Intel Corp.     1991-12-06
Assigns changes for X86 and 860 architecture of pre-release 2.0 of GNU package.
 

GCC960, GDB960, GAS960, GLD960, GSTRIP960, GAR960, GNM960, GSIZE960, LIBBFD.A   Intel   1991-09-16 (also 1991-07-26)
Assigns changes in release 1.3 of GNU960 package.
 
GDB     Intel           1995-05-11
Disclaims GDB for i860 Microprocessor OSF Operating System.
(This is a photocopy)

Re: intel 960 support Was: pentium?

[Jim Wilson]

	> There is also the issue of copyright assignments.  We can't use
	> Intel's code without a copyright assignment from Intel.  I am not
	> sure how hard it will be to get one; it might be easier to just
	> write new code from scratch in some cases.

	Maybe not that hard...  Below is what's on file already.

Except that none of these assignments are useful.  All of the existing
assignments are restricted to a particular patch or release, and the most
recent i960 related one is from 6 years ago.  If I wanted to, I could add
changes from a 6 year old GNU960 release, but I can not add changes from the
most recent GNU960 release.  I am really not very interested in 6 year old
sources.

What would be really useful is if Intel assigned all past/future i960 gcc
related changes to the FSF, but I seriously doubt that will happen.

I do believe that we can get an assignment for a particular GNU960 release
from Intel, because they have signed assignments in the past.  However, it
will take work on our part to get the assignment, because Intel is not going
to volunteer it.  And we will need to get another assignment everytime Intel
makes another GNU960 release.  It isn't clear if all of this work is
worthwhile.

Jim

Re: intel 960 support Was: pentium?

[Jim Wilson]

Yes, this is certainly one of the items on our list of things to look at
when we find the time.

However, the intel i960 support has many of the same issues as the pentium
support.  There are interesting ideas there, but many of them have been
implemented poorly, or implemented in such a way that they will work for the
i960, but will break other targets, and hence can't be used as is.  There is
also the issue of copyright assignments.  We can't use Intel's code without a
copyright assignment from Intel.  I am not sure how hard it will be to get one;
it might be easier to just write new code from scratch in some cases.

Jim

Re: intel 960 support Was: pentium?

[Robert Lipe]

Joel Sherrill wrote:
> On Wed, 1 Oct 1997, Neal Becker wrote:
> 
> > On a related subject - we use also use i960 here.  I have to use the
> > intel version, because they have added a number of features.
> > Unfortunately, their version is pretty out-of-date, and I'm not sure
> > they're maintaining it.  Any plans to incorporate any of intel's i960
> > improvements?

Intel released version a major overhaul of the tools about a year or 
so ago.  By that time, my involvement with i960 was long over.

I recall in late '95, perhaps early '96 doing a big shootout between the
Cygnus progressive compiler of that era and the Intel tools (which I recently
took great delight in removing, so I can't tell you the version number, but
it was < 4.0).    It was about a draw.   The Intel version contained some
chip-specific things for the JK and JA and could therefore dhrystone about
2-3% better.  However, the Cygnus version would actually work given any
non-trivial input. :-)

> Specifically what features are missing in egcs?

Gosh, I can't recall.   There were (obviously) chip-specific 
optimizations present that the Cygnus/FSF version didn't have.
It knew more about the pipelines.   The linker knew how to do 
jump to a jump sorts of optimizations.    Nothing earthshattering
that I recall.

The thing I do recall was the that the Intel version wasn't very
reliable and was always having to look over its shoulder.

RJL