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| author | Eelco Dolstra <eelco.dolstra@logicblox.com> | 2012-08-13T05·05-0400 |
|---|---|---|
| committer | Eelco Dolstra <eelco.dolstra@logicblox.com> | 2012-08-13T05·05-0400 |
| commit | b9e5b908ed29bfb6cd82837f9f57293c1f63e999 (patch) | |
| tree | bf83e68c67ec3e37720634c6ccca1d53594a3346 /src/libexpr/eval.cc | |
| parent | 4ccd48ce2478cbe1263605838969f89d5b745f0a (diff) | |
Provide an efficient implementation of ‘elem’
The one in Nixpkgs is O(n^2), this one is O(n). Big reduction in the number of list allocations. Statistics before (on a NixOS system config): time elapsed: 1.17982 size of a value: 24 environments allocated: 1543334 (39624560 bytes) list elements: 9612638 (76901104 bytes) list concatenations: 37434 values allocated: 1854933 (44518392 bytes) attribute sets allocated: 392040 right-biased unions: 186334 values copied in right-biased unions: 591137 symbols in symbol table: 18272 number of thunks: 1392467 number of thunks avoided: 1507311 number of attr lookups: 430801 number of primop calls: 691600 number of function calls: 1492502 Statistics after: time elapsed: 1.08683 size of a value: 24 environments allocated: 1384376 (35809568 bytes) list elements: 6946783 (55574264 bytes) list concatenations: 37434 values allocated: 1760440 (42250560 bytes) attribute sets allocated: 392040 right-biased unions: 186334 values copied in right-biased unions: 591137 symbols in symbol table: 18273 number of thunks: 1297673 number of thunks avoided: 1380759 number of attr lookups: 430802 number of primop calls: 628912 number of function calls: 1333544
Diffstat (limited to 'src/libexpr/eval.cc')
0 files changed, 0 insertions, 0 deletions