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kens a day ago

CAD was a very incremental process. Early chips were drawn by hand and the Rubylith masks were cut by hand with the help of a Coordinatograph. Later, Intel used a Xynetics plotter to cut the Rubylith. By 1974, layouts were digitized with a Calma GDS I so repeated cells could be handled automatically. By the time of the 8087, there was a lot of automation.

You might think that the 8087's shifter would be a regular grid, easy to lay out by hand. It turns out to be very optimized and irregular. (I traced it out by hand and it was a pain.)