loop unrolling does: trades code size for reduced loop overhead

Loop unrolling optimizes execution speed by reducing loop control instructions

Loop unrolling transforms a loop into a sequence of repeated statements, minimizing the overhead of loop control instructions like pointer arithmetic and loop termination tests. This optimization aims to increase a program's speed by decreasing the number of instructions executed within the loop.

Example

A loop that increments a counter 10 times can be unrolled into 10 separate increment statements, eliminating the loop's start and end checks.

Remember this

Reducing loop overhead can significantly improve program performance, especially in time-critical applications.

Text adapted from Wikipedia, licensed under CC BY-SA 4.0.

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