computer engineering Computer engineering (CoE or CpE) is a branch of electrical engineering and computer science that integrates several fields of computer science and electronic engineering required to develop computer hardware and software. Computer enginee ...

, an execution unit (E-unit or EU) is a part of the

central processing unit A central processing unit (CPU), also called a central processor, main processor or just processor, is the electronic circuitry that executes instructions comprising a computer program. The CPU performs basic arithmetic, logic, controlling, an ...

(CPU) that performs the operations and calculations as instructed by the

computer program A computer program is a sequence or set of instructions in a programming language for a computer to execute. Computer programs are one component of software, which also includes documentation and other intangible components. A computer progra ...

. It may have its own internal control sequence unit (not to be confused with the CPU's main control unit), some registers, and other internal units such as an

arithmetic logic unit In computing, an arithmetic logic unit (ALU) is a combinational digital circuit that performs arithmetic and bitwise operations on integer binary numbers. This is in contrast to a floating-point unit (FPU), which operates on floating point numb ...

(ALU), address generation unit (AGU),

floating-point unit In computing, floating-point arithmetic (FP) is arithmetic that represents real numbers approximately, using an integer with a fixed precision, called the significand, scaled by an integer exponent of a fixed base. For example, 12.345 can b ...

(FPU), load-store unit (LSU), branch execution unit (BEU) or some smaller and more specific components."Execution Unit" discussion from the University of Massachusetts Amherst
archived on the

Wayback Machine The Wayback Machine is a digital archive of the World Wide Web founded by the Internet Archive, a nonprofit based in San Francisco, California. Created in 1996 and launched to the public in 2001, it allows the user to go "back in time" and s ...

It is common for modern CPUs to have multiple parallel functional units within its execution units, which is referred to as superscalar design. The simplest arrangement is to use a single bus manager unit to manage the memory interface, and the others to perform calculations. Additionally, modern CPUs' execution units are usually pipelined.

References

Central processing unit Computer arithmetic {{Comp-eng-stub