This research is an attempt to reason about the control of parallel computation in the world of applicative programming languages. Applicative languages, in which computation is performed through function application and in which functions are treated as first-class objects, have the benefits of elegance, expressiveness and having clean semantics. Parallel computation and real-world concurrent activities are much harder to reason about than the sequential counterparts. Many parallel applicative languages have thus hidden most control details with their declarative programming styles, but they are not expressive enough to characterize many real world concurrent activities that can be easily explained with concepts such as message passing, pipelining and so on. Ease of programming should not come at the expense of expressiveness. Therefore, we design a parallel applicative language Pscheme such that programmers can express explicitly the control of parallel computation while maintaining ...

Formally establishing safety properties of software presents a grand challenge to the computer science community. Producing proof-carrying code, i.e., machine code with machine-checkable specifications and proofs, is particularly difficult for system softwares written in low-level languages. One central problem is the lack of verification theories that can handle the expressive power of low-level code in a modular fashion. In partic-ular, traditional type- and logic-based verification approaches have restrictions on either expressive power or modularity. This dissertation presents XCAP, a logic-based proof-carrying code framework for modular machine code verification. In XCAP, program specifications are written as gen-eral logic predicates, in which syntactic constructs are used to modularly specify some crucial higher-order programming concepts for system code, including embedded code pointers, impredicative polymorphisms, recursive invariants, and general references, all in a logical setting. Thus, XCAP achieves the expressive power of logic-based approaches and the modularity of type-based approaches. Its meta theory has been completely mech-anized and proved.