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A comment on C++ for Games: Performance, Allocations and Data Locality. Parent comment

Re:C++ for Games: Performance, Allocations and Data Locality by santaclaus on Monday May 30, 2016 @02:13AM (#11799846)
They compile down to the same code on a simple example in release.

Post increment: https://godbolt.org/g/k5rcPA

Pre increment: https://godbolt.org/g/WgfMzU

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Re:C++ for Games: Performance, Allocations and Data Locality by exDM69 on Monday May 30, 2016 @04:07AM (#11800183)
For std::vector, they should compile to the same thing, the iterator is just a pointer to a flat array. For std::map (ie. red-black tree) or something more complex, it might make a bigger difference. But even then, the iterator is quite light weight (just a pointer) so copying it is not a big deal.
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Re:C++ for Games: Performance, Allocations and Data Locality by nandno on Monday May 30, 2016 @05:45AM (#11800495)
Even for std::map gcc generates identical code:

https://godbolt.org/g/C6kooc

https://godbolt.org/g/7RS5PQ

godbolt is a great resource to see just how good modern compilers are.

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Re:C++ for Games: Performance, Allocations and Data Locality by SamReidHughes on Monday May 30, 2016 @10:14PM (#11804195)
I wouldn't say "even" -- that's just another type where the iterator is a trivially copyable/destructable object.
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