improve some IntSet operations #23138
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* IntSet has a new invariant: the length of the underlying BitArray is always a multiple of 64 * the size is set to the minimum possible: the underlying routines are in charge of allocating enough (like for other containers); this can help to obtain the last element faster (which is useful e.g in `rand(::IntSet)`) * _matched_map avoids extending a BitArray when unecessary (but doesn't work anymore for all 2^4 kinds of binary predicate, though it could be handled if needed in the future)
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| @inline in(n::Integer, s::IntSet) = get(s.bits, n, false) |
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Unrelated change, but simpler.
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@nanosoldier |
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Your benchmark job has completed - possible performance regressions were detected. A full report can be found here. cc @ararslan |
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stockcorr and array indexing regressions have a chance of being real, should keep an eye on the nightly results |
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Given ae17198#commitcomment-23501641 it might be worth looking into the array indexing regression? |
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Looking at the very few places in base where |
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doesn't inference use them in some key places? otherwise they'd likely be moved out to DataStructures |
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Inference uses them, but I thought it wouldn't influence the run time performance and the benchmarks. |
Now IntSet have the length of their underlying BitVector be a multiple of 64, so resizing them to something else breaks this invariant.
fix IntSet tests invalid since #23138
is always a multiple of 64
are in charge of allocating enough (like for other containers);
this can help to obtain the last element faster (which is useful
e.g in
rand(::IntSet))(but doesn't work anymore for all 2^4 kinds of binary predicate,
though it could be handled if needed in the future)
A case where this could be slower is for example in:
But I could not really/reliably measure a difference (disclaimer:
BenchmarkToolsis broken recently on my installation, so I use a hand-made "equivalent"), andsizehint!can help here. The improvements for some operations can be huge, e.g.symdiff!(a, b)wherea=IntSet([2^20]), b=IntSet([1])decreases from 45.07µs to 10ns. Also, something likerand(s)wheres=IntSet([1, 2, 3])decreases from about 980ns to 310ns.