Do you know about how many transistors are needed to implement the adder (or the FPU as a whole)? And how it scales with the width of the numbers (16 bit, 32 bit, etc)?

I've been curious about transistor counts for floating point units for a while, but it's hard to find information about them.

I count approximately 2014 transistors (including pull-ups) for the 69-bit adder. Each block of four bits takes approximately 117 transistors.