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* remove a condition that table size must be passed as power of 2 (#14926)Miran2020-07-081-4/+10
| | | | | | | | | | | | | | | * remove a condition that table size must be passed as power of 2 * remove power-of-2 condition from sets and sharedtables * remove power-of-2 condition from deques * use 'correctSize' for both branches * prettify changelog.md and fix typos * add a changelog entry * fix double-call of 'right-size' * fix the same thing in sets.nim * introduce a new internal proc `slotsNeeded` Deprecate the public proc `rightSize`, which is not needed anymore. Now it is an identity function, allowing the old code to work correctly and without extra allocations.
* Unwind just the "pseudorandom probing" part of recent sets,tables changes ↵c-blake2020-03-311-63/+17
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | (#13816) * Unwind just the "pseudorandom probing" (whole hash-code-keyed variable stride double hashing) part of recent sets & tables changes (which has still been causing bugs over a month later (e.g., two days ago https://github.com/nim-lang/Nim/issues/13794) as well as still having several "figure this out" implementation question comments in them (see just diffs of this PR). This topic has been discussed in many places: https://github.com/nim-lang/Nim/issues/13393 https://github.com/nim-lang/Nim/pull/13418 https://github.com/nim-lang/Nim/pull/13440 https://github.com/nim-lang/Nim/issues/13794 Alternative/non-mandatory stronger integer hashes (or vice-versa opt-in identity hashes) are a better solution that is more general (no illusion of one hard-coded sequence solving all problems) while retaining the virtues of linear probing such as cache obliviousness and age-less tables under delete-heavy workloads (still untested after a month of this change). The only real solution for truly adversarial keys is a hash keyed off of data unobservable to attackers. That all fits better with a few families of user-pluggable/define-switchable hashes which can be provided in a separate PR more about `hashes.nim`. This PR carefully preserves the better (but still hard coded!) probing of the `intsets` and other recent fixes like `move` annotations, hash order invariant tests, `intsets.missingOrExcl` fixing, and the move of `rightSize` into `hashcommon.nim`. * Fix `data.len` -> `dataLen` problem.
* [backport] pseudorandom probing for hash collision (#13418)Timothee Cour2020-02-191-16/+71
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* [other] prettify collections (#11695)Miran2019-07-091-4/+4
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* Initialized collections (#11094)Miran2019-04-291-0/+68
* tables: initialized by default * sets: initialized by default * DRY: extract shared functionality * add a changelog entry * fix errors * don't test include files * make it work for sharedtables * fix discovered bugs * add exhaustive tests