We are pleased to announce the 13th Annual Tcl/Tk conference (Tcl'2006), sponsored by Noumena Corporation , Digital Smarties , Eolas Technologies and ActiveState .

TJC: A Tcl to Java Compiler

Author: Mo DeJong

Abstract

A recent trend in corporate computing environments is the reimplementation of legacy systems on a Java based software platform. Significant long-term savings can be realized through use of a common software platform and tools, but the costs of software development and retraining of engineers remains high. If a legacy system can be ported to Java without having to rewrite existing code, then most software development and retraining costs can be avoided entirely. A large semiconductor manufacturer recently faced just such a challenge and decided to evaluate Jacl (Tcl interpreter written in Java) as a migration tool for a large legacy system implemented in Tcl. Jacl was found to be satisfactory in all areas except one, runtime execution speed. Native Tcl contains a runtime compiler and execution engine while Jacl supports only interpreted execution. As a result, native Tcl executes code from 10 to 50 times faster than Jacl. This paper introduces TJC, a Tcl to Java compiler that converts Tcl procs into Java bytecode and closes this performance gap. In many cases, TJC compiled Tcl code executes more quickly than the same code running in native Tcl. This paper describes the TJC compiler's initial design and implementation, demonstrates code generated for some simple examples, and details optimizations that have been implemented as the compiler has matured into production ready software. In addition, performance of TJC compiled code is compared to native Tcl and to other popular scripting languages implemented in Java.

Conference Committee

Contact Information

tcl2006@tcl.tk

Last modified: June 06, 2007