c639a78dc4
This is an implementation of a map and set for integer keys. It's an ordered container (by byte order, which is sorted order for integers and byte strings when done in the right direction) with O(1) worst-case lookup, removal and insertion. There's no rebalancing or rehashing so it's actually O(1) without amortizing any costs.
The fanout can be adjusted in multiples of 2 from 2-ary through 256-ary, but it's hardcoded at 16-ary because there isn't a way to expose that in the type system yet. To keep things simple, it also only allows `uint` keys, but later I'll expand it to all the built-in integer types and byte arrays.
There's quite a bit of room for performance improvement, along with the boost that will come with dropping the headers on `Owned` `~` and getting rid of the overhead from the stack switches to the allocator. It currently does suffix compression for a single node and then splits into two n-ary trie nodes, which could be replaced with an array for at least 4-8 suffixes before splitting it. There's also the option of doing path compression, which may be a good or a bad idea and depends a lot on the data stored.
I want to share the test suite with the other maps so that's why I haven't duplicated all of the existing integer key tests in this file. I'll send in another pull request to deal with that.
Current benchmark numbers against the other map types:
TreeMap:
Sequential integers:
insert: 0.798295
search: 0.188931
remove: 0.435923
Random integers:
insert: 1.557661
search: 0.758325
remove: 1.720527
LinearMap:
Sequential integers:
insert: 0.272338
search: 0.141179
remove: 0.190273
Random integers:
insert: 0.293588
search: 0.162677
remove: 0.206142
TrieMap:
Sequential integers:
insert: 0.0901
search: 0.012223
remove: 0.084139
Random integers:
insert: 0.392719
search: 0.261632
remove: 0.470401
@graydon is using an earlier version of this for the garbage collection implementation, so that's why I added this to libcore. I left out the `next` and `prev` methods *for now* because I just wanted the essentials first.
|
||
|---|---|---|
| .. | ||
| compiletest | ||
| driver | ||
| etc | ||
| libcore | ||
| libfuzzer | ||
| librust | ||
| librustc | ||
| librustdoc | ||
| librusti | ||
| librustpkg | ||
| libstd | ||
| libsyntax | ||
| libuv@da33bba7c0 | ||
| llvm@accc36b3e3 | ||
| rt | ||
| rustllvm | ||
| test | ||
| README.txt | ||
| snapshots.txt | ||
This is a preliminary version of the Rust compiler, libraries and tools Source layout: librustc/ The self-hosted compiler libcore/ The core library (imported and linked by default) libstd/ The standard library (slightly more peripheral code) libsyntax/ The Rust parser and pretty-printer rt/ The runtime system rt/rust_*.cpp - The majority of the runtime services rt/isaac - The PRNG used for pseudo-random choices in the runtime rt/bigint - The bigint library used for the 'big' type rt/uthash - Small hashtable-and-list library for C, used in runtime rt/sync - Concurrency utils rt/util - Small utility classes for the runtime. rt/vg - Valgrind headers rt/msvc - MSVC support rt/linenoise - a readline-like line editing library test/ Testsuite test/compile-fail - Tests that should fail to compile test/run-fail - Tests that should compile, run and fail test/run-pass - Tests that should compile, run and succeed test/bench - Benchmarks and miscellanea test/pretty - Pretty-printer tests test/auxiliary - Dependencies of tests compiletest/ The test runner librustpkg/ The package manager and build system librusti/ The JIT REPL librustdoc/ The Rust API documentation tool llvm/ The LLVM submodule libuv/ The libuv submodule rustllvm/ LLVM support code libfuzzer/ A collection of fuzz testers etc/ Scripts, editor support, misc