Analytic comparison of two advanced C language-based parallel programming models

There are two main approaches for designing parallel language. The first approach states that parallel computing demands new programming concepts and radical intellectual changes regarding the way we think about programming, as compared to sequential computing. Therefore, the design of such a parallel language must present new constructs and new programming methodologies. The second approach states that there is no need to reinvent the wheel, and serial languages can be extended to support parallelism. The motivation behind this approach is to keep the language as friendly as possible for the programmer who is the main bridge toward wider acceptance of the new language. In this paper we present a qualitative evaluation of two contemporary parallel languages: OpenMP-C and Unified Parallel C (UPC). Both are explicit parallel programming languages based on the ANSI C standard. OpenMP-C was designed for shared-memory architectures and extends the base-language by using compiler directives that annotate the original source-code. On the other hand, UPC was designed for distribute-shared memory architectures and extends the base-language by new parallel constructs. We deconstruct each parallel language into its basic components, show examples, make a detailed analysis, compare them, and finally draw some conclusions.