When you're making a game engine, there's a tradeoff when it comes to working on dev quality-of-life features vs game-facing features.
A factor I don't usually see discussed is the project's PITA Budget. It may take more swe-hours to implement a shortcut that saves 5 seconds at a time than it will ever pay back, but the qualitative difference in working without that 5s annoyance reduces the mental-strain cost of continuing to work on the project at all. As a motivation-bottlenecked solo dev, having good tools not only makes asset creation more efficient, but effectively gives you more hours in the month to work with.
today's small thing is interpreting a UI Label of just "\n" to be a shortcut for a linefeed, which lets us change this from
to
cutting lines-of-code in half
It's the sort of thing that makes actually* zero difference in the finished product, but it makes the daily life of being a game developer fractionally less frustrating, so that's satisfying.
*: If compilers can optimize across strcmp, which I strongly suspect they can, then they would literally compile into the same code
For funsies (because I'm stoned) let's pretend we're compiler engineers again. Why should this be optimizable? ui.labels() is a variadic template function that emits one call to ui.label() per argument, which has overloads for each type. the const char* overload has a clause at the top of it:
With inlining, we would get if (strcmp("\n", "\n") == 0), which a human programmer can clearly see is always true. Can compilers? Well, given that strcmp is a C Standard Library function, compilers are free to make special assumptions about how they work that may not be obvious from the type signature. We also would not be able to inline strcmp, because it's compiled separately (unless you're building your own libc from source, or if your libc ships bitcode which would be weird)
Anyway! So it stands to reason that some enterprising young lad may have realized that they can save 0.2ms on some benchmark by constant-folding strcmps, or by precomputing string manipulations, or whatever. How can we check? Godbolt.
Sure enough, even at -O1 clang is able to constant-fold the strcmps and turn test("foo") into just doSomethingElse()
This ramble didn't really have much of a point. C++ is a language built around zero-cost abstractions. There's something really satisfying about knowing enough about how the optimizer works, and what the language's semantics are, including its cost model, and thus being able to reason about what will actually get optimized away in practice.
