ICC++ is a new C++ concurrent dialect which allows sequential/parallel program versions to be maintained with single source, the construction of concurrent data abstractions, convenient expression of irregular and fine-grained concurrency, and supports high performance implementations. ICC++ provides annotations for potential concurrency, facilitating both sharing source with sequential programs and grain size tuning for efficient execution. ICC++ has a notion of object consistency which can be extended structurally and procedurally to implement larger data abstractions. Finally, ICC++ integrates arrays into the object system and hence the concurrency model. In short, ICC++ addresses concurrency and its relation to abstractions -- whether they are implemented by single objects, several objects, or object collections. The design of the language, its rationale, and current status are all described. Keywords concurrent object-oriented programming, concurrent languages, parallel...

iii To Cindy,

A concurrent object-oriented extension to the programming language Scheme, called Schematic, is described. Schematic supports familiar constructs often used in typical parallel programs (future and higher-level macros such as plet and pbegin), which are actually defined atop a very small number of fundamental primitives. In this way, Schematic achieves both the convenience for typical concurrent programming and simplicity and flexibility of the language kernel. Schematic also supports concurrent objects which exhibit more natural and intuitive behavior than the "bare" (unprotected) shared memory, and permit intra-object concurrency. Schematic will be useful for intensive parallel applications on parallel machines or networks of workstations, concurrent graphical user interface programming, distributed programming over network, and even concurrent shell programming.

Object-oriented techniques have been proffered as aids for managing complexity, enhancing reuse, and improving readability of irregular parallel applications. However, as performance is the major reason for employing parallelism, programmability and high performance must be delivered together. Using a suite of seven challenging irregular applications and the mature Illinois Concert system (a high-level concurrent object-oriented programming model backed by an aggressive implementation), we evaluate what programming efforts are required to achieve high performance. For all seven applications, we achieve performance comparable to the best reported for low-level programming means on large-scale parallel systems. In general, a high-level concurrent object-oriented programming model supported by aggressive implementation techniques can eliminate programmer management of many concerns -- procedure and computation granularity, namespace management, and low-level concurrency management. Our st...