“The Compiler Trick That Speeds Up Long Division” — what this page in the network covers. Long division is computationally expensive, but compilers have a clever trick to avoid it. In this video, Matt Godbolt demonstrates how compilers replace division by a constant with multiplication and bit shifts, using the magic of modular arithmetic. He shows a simple C program and the generated assembly code, revealing the optimization in action.
We also discuss the mathematical foundation behind this trick, including the concept of reciprocal multiplication and how compilers choose the right constants. This technique is a classic example of how compilers make our code run faster without us even knowing. Perfect for programmers who want to understand low-level optimizations. This listing links straight to the original page, where the content is available in full.