Q. What is an arithmetic processor?

A distinctive CPU necessitates most of the control and data processing hardware for implementing non-arithmetic functions. As the hardware costs are directly related to chip area, a floating point circuit being composite in nature is expensive to implement. They require not to be included in instruction set of a CPU. In such systems floating-point operations were applied by employing software routines.  

This implementation of floating point arithmetic is definitely slower than hardware implementation. Now question is whether a processor can be constructed just for arithmetic operations. A processor if devoted exclusively to arithmetic functions can be used to implement a full variety of arithmetic functions in hardware at a relatively low cost. This can be done in a single Integrated Circuit. So a special purpose arithmetic processor for performing only arithmetic operations can be constructed. This processor physically may be separate however can be utilized by CPU to execute complex arithmetic instructions. Please note in the absence of arithmetic processors these instructions can be executed using slower software routines by the CPU itself. So this auxiliary processor improves the speed of execution of programs having several complex arithmetic computations.

An arithmetic processor also assists in reducing program complexity as it provides a richer instruction set for a machine. A number of the instructions which can be assigned to arithmetic processors can be related to subtraction, addition, division and multiplication oftrigonometric functions, logarithms, exponentiation and other floating point numbers.