Grumpy Old Men, Opacity, and Optimizers

Today I’m channeling my inner grumpy old man. And these guys are helping. (I am not old enough to pull off such a face by myself, although life is rapidly helping me get there. ;-)

Grumpy old men.

The reason I’m feeling grumpy is that I’ve had another in a long, long line of conversations about how to write faster code.

It’s not that optimization experts are dumb. Far from it. They are invariably smart, and in general, they are better informed than I am about how pipeline burst cache and GPUs and RAM prefetch algorithms work. I generally learn a lot when I talk to guys like this.

I applaud their passion, even if I think they sometimes get carried away.

No. What’s making me grumpy is that after decades of hard work, we still have compilers that encourage a culture of black magic and superstition around this topic. I thought I signed up for computer science, not voodoo.

To show you what I mean, let’s talk about the humble inline keyword in C and C++. The amount of FUD and nonsense around it is really unfortunate. How many of the following have you heard?
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