| Budget Amount *help |
¥2,400,000 (Direct Cost: ¥2,400,000)
Fiscal Year 1997: ¥300,000 (Direct Cost: ¥300,000)
Fiscal Year 1996: ¥800,000 (Direct Cost: ¥800,000)
Fiscal Year 1995: ¥1,300,000 (Direct Cost: ¥1,300,000)
|
|---|
| Research Abstract |
The outstanding features of concurrent logic programming languages such as GHC (Guarded Horn Clauses) are the extreme simplicity of its communication and synchronization mechanisms and its flexibility in describing concurrency. To make the languages really practical, however, static analysis needs to play key roles both in programming and optimization.
The head investigator had worked on the theoretical aspects of the static mode system (strong moding) for GHC and designed the algorithms for mode analysis. In this project, we worked on the practical aspects of strong moding and demonstrated its effectiveness from the following respects :
1. Implementation of a mode analyzer - We implemented the mode analyzer klint for the concurrent logic language KL1 using KL1 itself as an implementation language. The system was revised several times until it could process large, real-life programs.
2. Descriptive power under strong moding - We demonstrated, through the analysis of various real-life Eli programs, that concurrent logic languages with strong moding are as practical and expressive as those without strong moding.
3. Program diagnosis based on strong moding - Strong moding turned out to be extremely useful for the static detection of program errors. We designed and implemented a set of algorithms for analyzing the errors of non-well-moded programs efficiently. Furthermore, we proposed a method of automated error correction and showed that it worked quite well for small program errors.
4. Optimization based on strong moding - We demonstrated that, by using type and linearity information in addition to mode information, many of runtime operations such as tag checking could be eliminated, leading to performance not too different from that obtained by procedural programs.
|
