ramkumar@cs.uiuc.edu (Balkrishna Ramkumar) (10/06/89)
We would like to announce the availability of our parallel Prolog compiler to the Prolog community. The compiler is designed to run on both shared and nonshared memory machines and is based on the Reduce-OR process model (and is therefore called ROLOG (for programming using Reduce-Or LOGic). It supports both AND and OR parallel execution of logic programs. Currently, it has been ported to the Encore Multimax, the Sequent (Balance and) Symmetry, the Alliant FX/8, the Intel iPSC/2 hypercube and can run in uniprocessor mode on any machine supporting unix (like a Sun, for example). The current release is a preliminary version which does not have a few features that most take for granted. For example, there is no read-eval loop yet. It will be necessary to create files with Prolog programs with one query per file. This file can be compiled using a code generator, and the generated code can be run subsequently on an abstract machine simulator that runs on any one of the above machines. The read-eval loop should be available in the next version of the compiler. Also, several builtins like setof, bagof, and side-effect builtins like assert and retract are not supported. Annotated Prolog programs are accepted as input by the compiler. We have designed the compiler to permit either hand annotations to the Prolog programs, or if people choose, add preprocessing modules to perform static analyses and do the annotations automatically. We hope that this will prove useful to researchers in static analysis. It also provides compiler directives for grainsize control, which permits certain predicates to be executed sequentially only. We are currently formulating a licence for the ROLOG compiler that is acceptable to the legal department of the University of Illinois. We have proposed a licence along the same lines as the SB-Prolog licence and it is currently being reviewed. The software is nevertheless copyrighted by the University of Illinois. Until an acceptable licence is available, we are requested not to make the software publicly available via anonymous ftp. Anybody wishing to obtain a copy of the compiler can send mail to ramkumar@cs.uiuc.edu and we will be more than happy to make it available to you. We request you to honour the spirit of the SB-Prolog licence applied to $ROLOG$ until these legal issues can be dealt with. (We do not expect this take more than a week or two at the most!) ROLOG has been implemented as a MACHINE-INDEPENDENT application on a parallel programming run time support system called the CHARE KERNEL. The files that contain the CHARE-KERNEL files are needed to support the compiler. The CHARE KERNEL is not being "officially" released with ROLOG, but will also be supplied with the compiler to those requesting it. In addition, a manual describing how to use the compiler is also available to users along with the software. We look forward to hearing from many of you. ram Email address: ramkumar@cs.uiuc.edu