Announcing new version of LaTTe JVM and JIT Compiler (fwd)

Archie Cobbs archie at
Wed Oct 25 08:31:10 PDT 2000


----- Forwarded message from Prof. Soo-Mook Moon -----

>From smoon at Wed Oct 25 06:48:40 2000
Date: Wed, 25 Oct 2000 20:20:53 +0900 (KST)
From: "Prof. Soo-Mook Moon" <smoon at>
Message-Id: <200010251120.UAA07667 at>
To: archie at
Subject: Announcing new version of LaTTe JVM and JIT Compiler
Content-Length:  3369

         My apologies if you receive multiple copies...

Subject: Announcing new release of LaTTe open-source Java Virtual Machine,
         with performance improvements

Version 0.9.1 of the LaTTe virtual machine has been released.  LaTTe is a
freely available virtual machine intended to execute Java classes.  It
can be obtained from <>.

LaTTe is research prototype for the study of dynamic (just-in-time)
compilation techniques.  Among its features are:

* A fast and effective JIT compiler with
  - efficient register mapping and allocation
  - "traditional" optimizations (e.g., common subexpression elimination)
  - object-oriented optimizations (e.g., customization and specialization)

* A limited framework for adaptive compilation, which is currently
  based on method run counts.

* A reasonably fast bytecode interpreter, intended to be used with
  the adaptive compilation framework.

* Lightweight monitors.

* On-demand translation of exception handlers.

* A fast, non-incremental garbage collector.

As a result, the performance of the LaTTe JVM is competitive with that
of commercial JVMs, such as Sun's JDK 1.2 production release and
JDK 1.3 release candidate client/server VMs.

Changes from version 0.9.0 include:

* Addition of new optimizations such as faster class inclusion tests,
  LOOKUPSWITCH optimization, de-virtualization of method invocations, and
  the use of native 64 bit instructions. These result in a 10% performance
  improvement in our benchmarks.

* Refinements in exception handling.

* Improved garbage collector, which now does selective sweeping.

On UltraSPARC, LaTTe 0.9.1 is better than the latest Sun JVMs by as much as
a geometric mean of 25% on SPECjvm98, and of 30% on Java Grande, in elapsed
time measurements.

LaTTe was initially based on Kaffe 0.9.0, although much code has now been 
rewritten in a clean room environment.  LaTTe runs on top of Solaris 2.5 or
higher on UltraSPARCs.

LaTTe was developed by the MASS Laboratory at Seoul National University, 
with sponsorship from IBM T.J. Watson Research Center.  It is free software, 
being licensed under BSD-like terms.

To obtain source code, documentation, and support, please visit
<>.  This site also contains many publications
describing the algorithms used in the LaTTe JVM.

We invite volunteers worldwide to join our LaTTe open-source development
team and help us implement the exciting, leading edge JIT compiler, VM and
instruction level parallelism optimizations to come. One on-going project 
where we would like help now is to integrate LaTTe back into the current 
version of Kaffe.

Thank you for your time in reading this announcement.

If you have any questions about LaTTe, or would like to join our team,
please contact us at <smoon at>, and we will be happy to help 
to the extent we can.  Please feel free to pass this announcement on to other
colleagues who might be interested.  We hope you will enjoy the LaTTe web site.

Prof. Soo-Mook Moon
Seoul National University
smoon at

Dr. Kemal Ebcioglu
IBM T.J. Watson Research Center
kemal at

* Sun, Java, UltraSPARC, Solaris are trademarks of Sun.

----- End of forwarded message from Prof. Soo-Mook Moon -----
Archie Cobbs     *     Packet Design     *

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