Arithmetic logic unit (ALU)

The number of arithmetic operations that a particular ALU supports may be limited to addition and subtraction, or might include multiplication, division, trigonometry functions such as sine, cosine, etc., and square roots . Some can only operate on whole numbers (integers ) whilst others use floating point to characterize real numbers , albeit with limited precision. However, any computer that is capable of performing just the simplest operations can be programmed to break down the more complex operations into simple steps that it can perform. Therefore, any computer can be programmed to perform any arithmetic operation-although it will take more time to accomplish this if its ALU does not directly support the operation. An ALU may also compare numbers and return boolean truth values (true or false) depending on whether one is equal to, greater than or less than the other ("is 64 greater than 65? ").
Logic businesses involve Boolean logic : AND , OR , XOR , and NOT . These can be useful for creating complicated conditional statements and processing boolean logic .
Superscalar computers may contain multiple ALUs, allowing them to process several instructions simultaneously. [66] Graphics processors and computers with SIMD and MIMD features often contain ALUs that could perform arithmetic on vectors and matrices .