Re:How to Adopt Modern C++17 into Your C++ Code [video]
by alexeiz on Thursday May 10, 2018 @03:18PM
(#17042113)
-Os is pretty much useless. For comparison, I compiled my (reasonably sized) project with -Os and got a 12MB statically linked binary. But with -O3, the binary size is only 4.2MB. Not only -O3 produces faster code but it's also smaller.
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Re:How to Adopt Modern C++17 into Your C++ Code [video]
by msla on Thursday May 10, 2018 @04:44PM
(#17042796)
In modern systems with caches and a typical penalty for going out to RAM, is it still possible for larger code to be faster?
Re:How to Adopt Modern C++17 into Your C++ Code [video]
by gpderetta on Friday May 11, 2018 @05:42AM
(#17045994)
Yes. Caches actually work. And work quite well for code. Of course there are pathological cases.
Also, static size does not mean anything. The only thing that matter is the dynamic size (i.e. the instructions that are actually fetched at runtime: code that isn't run or run rarely doesn't matter (then again, such code is a prime candidate to be compiled with -Os).