How floats are computed on a machine without an FPU

Question

C language has a data-type float. Some machines have a floating point processor that carries out all the floating point computations. My question is: Could there be some machines without a floating point processor? How do such machines use floating point?

Answer 1

Many small controllers do not have floating point units. In that case, there is a floating point software library.

In the mid-1980s, we considered ourselves blessed if our system had an 8087, the FPU for the 8086 and 8088. Unfortunately our software had to work correctly if an 8087 was present or not. That meant trapping and emulating 8087 instructions if it was missing.