avoid zeroMem when resizing trivial seq:s #109
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arnetheduck
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zah
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Jun 23, 2022
| when T is SomeNumber: | ||
| # `setLen` does costly zero:ing both when growing _and_ shrinking | ||
| if tgt.len > src.len or tgt.len < src.len div 4: | ||
| tgt = newSeqUninitialized[T](src.len) |
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Memory allocation and garbage collection is faster than skipping some memset(0) calls? Doesn't sounds universally true.
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it's true for large allocations above all because allocation doesn't depend that much on the size of the allocation - it seemed to give an improvement in vtune - see also nim-lang/Nim#19728 and nim-lang/Nim#19727
might as well grab a new sequence instead
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might as well grab a new sequence instead