In
computer engineering
Computer engineering (CE, CoE, or CpE) is a branch of engineering specialized in developing computer hardware and software.
It integrates several fields of electrical engineering, electronics engineering and computer science.
Computer engi ...
, an execution unit (E-unit or EU) is a part of a
processing unit that performs the operations and calculations forwarded from the
instruction unit. It may have its own internal control sequence unit (not to be confused with a
CPU's main
control unit
The control unit (CU) is a component of a computer's central processing unit (CPU) that directs the operation of the processor. A CU typically uses a binary decoder to convert coded instructions into timing and control signals that direct the op ...
), some
registers, and other internal units such as an
arithmetic logic unit
In computing, an arithmetic logic unit (ALU) is a Combinational logic, 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 ...
,
address generation unit,
floating-point unit
A floating-point unit (FPU), numeric processing unit (NPU), colloquially math coprocessor, is a part of a computer system specially designed to carry out operations on floating-point numbers. Typical operations are addition, subtraction, multip ...
,
load–store unit,
branch execution unit or other smaller and more specific components, and can be tailored to support a certain
datatype, such as
integers
An integer is the number zero (0), a positive natural number (1, 2, 3, ...), or the negation of a positive natural number (−1, −2, −3, ...). The negations or additive inverses of the positive natural numbers are referred to as negative in ...
or
floating-points.
It is common for modern processing units 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 execution units are usually
pipelined.
References
Central processing unit
Computer arithmetic
{{Comp-eng-stub