yuri gurevich Can any algorithm, never mind how abstract, be modeled by a generalized machine very closely and faithfully? ... If we stick to one abstract level (abstracting from low-level details and being oblivious to a possible higher-level picture) and if the states of the algorithm reflect all the pertinent information, then a particular small instruction set suffices in all cases. adapted from Yuri Gurevich, "Sequential Abstract State Machines Capture Sequential Algorithms"
We have designed, implemented, and evaluated AtomCaml, an extension to Objective Caml that provides a synchronization primitive for atomic (transactional) execution of code. A first-class primitive function of type (unit->'a)->'a evaluates its argument (which may call other functions, even external C functions) as though no other thread has interleaved execution. Our design ensures fair scheduling and obstruction-freedom. Our implementation extends the Objective Caml bytecode compiler and run-time system to support atomicity. A logging-and-rollback approach lets us undo uncompleted atomic blocks upon thread pre-emption, and retry them when the thread is rescheduled. The mostly functional nature of the Caml language and the Objective Caml implementation's commitment to a uniprocessor execution model (i.e., threads are interleaved, not executed simultaneously) allow particularly efficient logging.
Chuck Thacker is building a new research computer called the BEE3. There was a time, years ago, when computer architecture was a most exciting area to explore. Talented, young computer scientists labored on the digital frontier to devise the optimal design, structure, and implementation of computer systems. The crux of that work led directly to the PC revolution from which hundreds of millions benefit today. Computer architecture was sexy. These days? Not so much. But Chuck Thacker aims to change that.
My existing research is mainly focused on lightweight generic programming techniques and the essence of (OO-style) design patterns. * Modular Visitor Components: A Practical Solution to the Expression Families Problem Bruno C. d. S. Oliveira ECOOP 2009. * Scala for Generic Programmers Bruno C. d. S. Oliveira, Jeremy Gibbons In Ralf Hinze, editor, Proceedings of the ACM SIGPLAN Workshop on Generic Programming (WGP'08) July 2008. * Objects to Unify Type Classes and GADTs Bruno C. d. S. Oliveira, Martin Sulzmann ICFP 2008