Scalar processors are a class of computer processors that process only one data item at a time. Typical data items include integers and floating point numbers.

Classification

A scalar processor is classified as a single instruction, single data ( SISD) processor in Flynn's taxonomy. The Intel 486 is an example of a scalar processor. It is to be contrasted with a vector processor where a single instruction operates simultaneously on multiple data items (and thus is referred to as a single instruction, multiple data ( SIMD) processor). The difference is analogous to the difference between scalar and vector arithmetic. The term ''scalar'' in computing dates to the 1970 and 1980s when vector processors were first introduced. It was originally used to distinguish the older designs from the new vector processors.

Superscalar processor

superscalar A superscalar processor is a CPU that implements a form of parallelism called instruction-level parallelism within a single processor. In contrast to a scalar processor, which can execute at most one single instruction per clock cycle, a sup ...

processor (such as the Intel P5) may execute more than one instruction during a clock cycle by simultaneously dispatching multiple instructions to redundant functional units on the processor. Each functional unit is not a separate CPU core but an execution resource within a single CPU such as an arithmetic logic unit, a bit shifter, or a multiplier. The Cortex-M7, like many consumer CPUs today, is a superscalar processor.

Scalar data type

A scalar data type, or just scalar, is any non- composite value. Generally, all basic primitive data types are considered scalar: * The boolean data type (bool) * Numeric types ( int, the floating point types float and double) * Character types (

char 
Char may refer to:
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*Char Fontane, American actress
*Char Margolis, American spiritualist
* René Char (1907–1988), French poet
*The Char family of Colombia:
** Fuad Char, Colombian senator
** Alejandro Char Chaljub, mayor of Barranquilla  ...

and

string 

String or strings may refer to:

*String (structure), a long flexible structure made from threads twisted together, which is used to tie, bind, or hang other objects
 Arts, entertainment, and media Films
*  ''Strings'' (1991 film), a Canadian anim ...

) A variable (that is, a named location containing a scalar data type) is sometimes referred to as a "scalar".

References

Central processing unit {{Compu-hardware-stub

Classification

Superscalar processor

Scalar data type

See also

References