I didn't find what , exactly, this IC is but here is an interesting [http://www.applelogic.org/APPLEASICs.html|site] that lists many of the IC's used in Apple computers. The closest match is the 344S0607-A and it dates back to the Apple IIc.
VLSI, the manufacturer, did custom ASICS so as such this is not a CPU but an application specific IC. Hopefully, @mayer will have more info.