Curious Kaffe vs. jdk speed test results under Linux

Per Bothner bothner at
Sun Jan 3 11:52:50 PST 1999

> may I ask you what your (or Cygnus's) point of view on using egcs for
> other VMs is?

First, as it is free software, so you are of course free to 
modify it.

On the other hand, we may have mixed feelings about competing
projects or companies using our work.  If they contribute back
(which includes being willing to sign necessary copyright
assignments) useful code that will improve the compiler in
general, that is of course great.  If people just rip off our
work without even an acknowledgement (which has happened), that
is really annoying (though it tends to backfire in the long run).
If we get a bunch of patches that make gcj generate code for some
other VM, that complicate the implementation without helping
improve things for us, well you can understand we might be less
than thrilled.

> It seems to me that one possibility of doing that would be to
> modularize the egcs code to allow for VM-specific different modules,
> which include all VM-dependencies.

Well, if we were going to consider merging in patches to support
some other VM, they would have to be clean and modular.  A framework
making it easier to support other VMs would be helpful.

Still, I think if Kaffe wants to use gcj, it might be better
long-term to move Kaffe closer to the ABI used by gcj.  The
main problem is that the gcj ABI is still evolving rapidly.
It will not stabilize until we support ClassLoader.defineClass,
JNI, and full reflection.

> These modules could then be activated with a cmdline switch.

Well, we do intend to support building customized Java
environments.  E.g. embedded systems may want no or minimal
reflective data.  So in that sense we will probably provide
multiple closely related ABIs in any case.  Whether this
will be a compiler switch or require compiler re-building
is an open question.

> Has any effort been made to modularize egcs in this fashion?

Well, we are now concentrating on getting a fully functional
and solid system.  Worrying about how to best support other VMs
is low on the priority list.

	--Per Bothner
Cygnus Solutions     bothner at

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