Cool Compiler Tidbits - Matt Godbolt

www.meetup.com/CppLondon/even...
We use compilers every day, but how often do we stop to think about the kinds of amazing things they do for us? Modern compilers are a feat of engineering and in this talk Matt will demonstrate just a few of the very clever things they do for you.
Matt will use Compiler Explorer to show how simple, easy to read code can be turned into amazing optimized, efficient assembly code. Writing clear, readable code that's also efficient hinges on being able to trust your compiler's code generator. By the end of this talk, you'll be able to read assembly well enough to be able to appreciate your compiler, and have an understanding of what it can - and can't - optimize for you.
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Matt is a C++ programmer and occasional verb. He loves writing efficient code and sharing his passion about how computers work under the hood. An engineer at Aquatic, he has previously worked in cryptocurrencies, at other trading firms, on mobile apps at Google, run a C++ tools company and spent more than a decade making console games. When not tinkering on Compiler Explorer, Matt enjoys working on emulators for old 8-bit computer hardware.

[@Ash-qp2yw]

A really fun talk - I want to try a small personal project in asm at some point, although it's relatively overwhelming to look at

[@kwitee]

The version with 8 partial accumulators will produce a faster AND more accurate sum, but the compiler has not been told to produce an accurate sum, just THIS sum. Careful what you ask for!