Syntax:

Since replicas may be used to optimize existing programs, syntactic support to create replicas without modifying the structure of the original programs is beneficial. In other words, if the replication mechanism is provided as library functions, we may have to modify the structure of the original programs, causing loss of clarity and portability. High Performance Fortran (HPF)'s distribution directives are declarative annotations (comments) which allow the programmers to control the distribution and replications in a non-intrusive manner to base-level programs[3]. The key idea is to provide directives as comments, so that they are non-intrusive. However, the syntax and semantics of HPF directives are fixed and not extensible. Instead, we propose the annotations as non-intrusive syntactic extensions at the base-level, and ways of meta-programming to define the associated interpretation of annotations at the meta-level.