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Electronic
Systems Design Seminar
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Bluespec: Why chip design can't be left to EE's
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A 5M-gate ASIC is
common place in 180nm technology today. We may see
50M to 100M-gate ASICs within a decade as technology improves to sub
90nm. (Fully custom-designed microprocessors are, of course, much
denser and faster then ASICs but also require dramatically more design
resources). Numerous problems related to process and design need to be
solved before such large chips will become commonplace. Some of these
problems, e.g., leaky transistors, porous oxide, controlling multiple
Vt's are clearly in the domain of EE's but computer scientists are much
better equipped to solve the new problems related to the
design-in-the-large. Large designs have to be conceived and executed in
terms of a hierarchy of blocks. The hierarchy cannot be constructed in
an ad hoc manner but should use some method of composition
systematically. Bluespec is a language/methodology that promotes
correctness-by-construction. Its underlying execution model is based on
atomic actions on state elements (flip-flops, registers, ...), i.e.,
any legal behavior is explainable in a terms of a sequence of atomic
actions on the state. Bluespec has facilities for expressing highly
parameterized modules ('generic classes" in the language sense) and an
expressive language to compose modules. The expressivity of the
language has no limits because its semantics are orthogonal to hardware
execution semantics -- the source program is turned into a flat
interconnection of modules by "static elaboration" during the compile
phase.
In this talk I will present Bluespec via examples and show some of the
designs done so far.
Bluespec is a joint work of people at MIT and Sandburst Corporation.
Arvind is the
Johnson Professor of Computer Science and Engineering at
the Massachusetts Institute of Technology. As the Founder and President
of Sandburst, a fabless semiconductor company, Arvind led the Company
from its inception in June 2000 until his return to MIT in August 2002.
His work at MIT on high-level specification and description of
architectures and protocols using Term Rewriting Systems (TRSs),
encompassing hardware synthesis as well as verification, laid the
foundations for Sandburst and more recently Bluespec Inc. Previously,
he contributed to the development of dynamic dataflow architectures,
and together with Dr R.S.Nikhil published the book "Implicit Parallel
Programming in pH". Arvind is an IEEE Fellow and was awarded the
Charles Babbage Outstanding Scientist Award in 1994. He has received
the Distinguished Alumni Awards from the Indian Institute of
Technology, Kanpur, and the University of Minnesota.