I suspect by the time you’ve disabled all the compiler “optimisations” that woul... | Hacker News

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		bigiain on Oct 28, 2021 \| parent \| context \| favorite \| on: 55 GiB/s FizzBuzz I suspect by the time you’ve disabled all the compiler “optimisations” that would lie knock a few orders of magnitude of performance off the directly translated algorithm, you may as well have written the assembler to start with… And you probably can’t fine tune your C/C++ to get this performance without knowing exactly what processor instructions you are trying to trick the compiler into generating anyway.

kccqzy on Oct 28, 2021 [–]

> without knowing exactly what processor instructions you are trying to trick the compiler into generating

In fact, in this case you know exactly what processor instructions the compiler is going to generate. You are using AVX intrinsics after all.

And no, compiler optimizations work well with these intrinsics.

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