alt Hacker NewsI'd wager a lot of money that the huge majority of software engineers are not aware of almost any transformations that an optimizing compiler does. Especially after decades of growth in languages where most of the optimization is done in JIT rather than a traditional compilation process.
The big thing here is that the transformations maintain the clearly and rigorously defined semantics such that even if an engineer can't say precisely what code is being emitted, they can say with total confidence what the output of that code will be.
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fragmede • yesterday at 10:52 PM
They can't! They can fairly safely assume that the binary corresponds correctly to the C++ they've written, but they can't actually claim anything about about the output other than "it compiles".
> the huge majority of software engineers are not aware of almost any transformations that an optimizing compiler does
They may not, but they can be. Buy a book like "Engineering a Compiler", familiarize yourself with the Optimization chapters, study some papers and the compiler source code (most are OSS). Optimization techniques are not spell locked in a cave under a mountain waiting for the chosen one.
We can always verify the compiler that way, but it's costly. Instead, we trust the developers just like we trust that the restaurant's chef are not poisoning our food.