Editing Silicon compiler (section)

== Overview ==
Silicon compilation takes place in three major steps:
* Use high level [[C to HDL]] converter
* Convert a [[Hardware description language|hardware-description language]] such as [[Verilog]] or [[VHDL]] into logic (typically in the form of a "[[netlist]]").
* Place equivalent [[logic gate]]s on the IC. Silicon compilers typically use standard-cell libraries provided by manufacturers so that they do not have to worry about the actual integrated-circuit layout and can focus on the placement.
* Routing the standard cells together to form the desired logic.

Silicon compilation was first described in 1979 by David L. Johannsen, under the guidance of his thesis adviser, [[Carver Mead]].<ref name="Johannsen">Johannsen, D. L., "Bristle Blocks: A Silicon Compiler," Proceedings 16th Design Automation Conference, 310–313, June 1979.</ref>

Johannsen, Mead, and Edmund K. Cheng subsequently founded Silicon Compilers Inc. (SCI) in 1981.

Edmund Cheng designed an Ethernet Data Link Controller chip<ref name="Cheng">Edmund K. Cheng, "The Design of an Ethernet Data Link Controller Chip", 26th IEEE Computer Society International Conference, COMPCON Spring 83, San Francisco, Feb 25-Mar 3, 1983, pp. 157–160.</ref> in 1981–82 using structured design methodology, in order to drive the software and circuit-library development at SCI. The project went from concept to chip specification in 3 months, and from chip specification to tape-out in 5 months. Fabricated using a 3-[[micrometre|micron]] NMOS process, the chip measured 50,600 square mils in die area, and was being marketed and manufactured in volume-production by 1983 under license from SCI.

[[John Wawrzynek]] at Caltech used some of the earliest silicon compilers in 1982 as part of the "Yet Another Processor Project" (YAPP), akin to [[Yacc|YACC]].<ref>
"Silicon compilers and foundries will usher in user-designed VLSI" article
by Carver A. Mead and George Lewicki. Caltech.
"Electronics" magazine 1982 Aug 11.
</ref>

In 1983–84, the SCI team designed and implemented the data-path chip used in the [[MicroVAX]] in seven months.
MicroVAX's data-path chip contains the entire 32-bit processor, except its microcode store and control-store sequencer, and contains 37,000 transistors.
At the time, chips with similar levels of complexity required about 3 years to design and implement.
Including those seven months, [[Digital Equipment Corporation]] completed the design and implementation of the MicroVAX within one year.
<ref name="Johnson">"Silicon compiler lets systems engineers design their own VLSI chips", article by Stephen C. Johnson of Silicon Compilers Inc. in "Electronic Design" magazine, October 4, 1984, pp. 167–181.</ref>