Cool, I thought this was a CPU custom designed for Doom, but I guess that's just a 486 :)

edit: I went to down a quick hole "The historical footnote is that a version of this genuinely happened. SNES Doom shipped with a Super FX 2 in the cartridge, a custom RISC chip with a pixel-plot instruction, because the console's own CPU had no chance. Jaguar and PlayStation ports both moved the rasteriser onto dedicated hardware. Doom's design was shaped by the absence of an FPU, and then hardware kept getting built to catch up with it."