Deriving Abstract Semantics for Forward Analysis of Normal Logic Programs

The problem of forward abstract interpretation of {\em normal} logic programs has not been formally addressed in the literature although negation as failure is dealt with through the built-in predicate ! in the way it is implemented in Prolog. This paper proposes a solution to this problem by deriving two generic fixed-point abstract semantics $F^{b}and$F^\diamond for forward abstract interpretation of {\em normal} logic programs. $F^b$ is intended for inferring data descriptions for edges in the program graph where an edge denotes the possibility that the control of execution transfers from its source program point to its destination program point. $F^{\diamond }$ is derived from $F^b$ and is intended for inferring data descriptions for textual program points.