Tag: #optimization

Quickly checking for a zero byte in C using bitwise operations

How to check if a 64-bit word contains a zero byte. A step-by-step example and a proof of correctness. 2017-01-24

How can I do modulo with a bitmask in C?

Use i & (n-1) to compute i % n, when n is a power of two. This avoids the modulo operation. 2016-12-10

What does the restrict keyword mean in C?

The restrict keyword in C is a type qualifier that indicates a pointer parameter points to an object not accessed through any other pointer in the function’s scope. This allows the compiler to make optimizations. 2016-12-03

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