/std/cs/_std/haxe/ds/IntMap.hx
Haxe | 455 lines | 351 code | 59 blank | 45 comment | 79 complexity | f41b234797fa30d8319ca79ccc309a19 MD5 | raw file
- /*
- * Copyright (c) 2005, The haXe Project Contributors
- * All rights reserved.
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are met:
- *
- * - Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- * - Redistributions in binary form must reproduce the above copyright
- * notice, this list of conditions and the following disclaimer in the
- * documentation and/or other materials provided with the distribution.
- *
- * THIS SOFTWARE IS PROVIDED BY THE HAXE PROJECT CONTRIBUTORS "AS IS" AND ANY
- * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
- * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
- * DISCLAIMED. IN NO EVENT SHALL THE HAXE PROJECT CONTRIBUTORS BE LIABLE FOR
- * ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
- * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
- * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
- * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
- * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
- * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH
- * DAMAGE.
- */
- package haxe.ds;
- import cs.NativeArray;
- /*
- * This IntMap implementation is based on khash (https://github.com/attractivechaos/klib/blob/master/khash.h)
- * Copyright goes to Attractive Chaos <attractor@live.co.uk> and his contributors
- *
- * Thanks also to Jonas Malaco Filho for his Haxe-written IntMap code inspired by Python tables.
- * (https://jonasmalaco.com/fossil/test/jonas-haxe/artifact/887b53126e237d6c68951111d594033403889304)
- */
- @:coreApi class IntMap<T>
- {
- private static inline var HASH_UPPER = 0.7;
- private var flags:NativeArray<Int>;
- private var _keys:NativeArray<Int>;
- private var vals:NativeArray<T>;
- private var nBuckets:Int;
- private var size:Int;
- private var nOccupied:Int;
- private var upperBound:Int;
- private var cachedKey:Int;
- private var cachedIndex:Int;
- public function new() : Void
- {
- cachedIndex = -1;
- }
- public function set( key : Int, value : T ) : Void
- {
- var x:Int;
- if (nOccupied >= upperBound)
- {
- if (nBuckets > (size << 1))
- resize(nBuckets - 1); //clear "deleted" elements
- else
- resize(nBuckets + 1);
- }
- var flags = flags, _keys = _keys;
- {
- var mask = nBuckets - 1;
- var site = x = nBuckets;
- var k = hash(key);
- var i = k & mask;
- //for speed up
- if (flagIsEmpty(flags, i)) {
- x = i;
- } else {
- var inc = getInc(k, mask);
- var last = i;
- while (! (isEither(flags, i) || _keys[i] == key) )
- {
- i = (i + inc) & mask;
- #if DEBUG_HASHTBL
- if (i == last)
- {
- throw "assert";
- }
- #end
- }
- x = i;
- }
- }
- if (flagIsEmpty(flags, x))
- {
- _keys[x] = key;
- vals[x] = value;
- setIsBothFalse(flags, x);
- size++;
- nOccupied++;
- } else if (flagIsDel(flags, x)) {
- _keys[x] = key;
- vals[x] = value;
- setIsBothFalse(flags, x);
- size++;
- } else {
- assert(_keys[x] == key);
- vals[x] = value;
- }
- }
- @:final private function lookup( key : Int ) : Int
- {
- if (nBuckets != 0)
- {
- var flags = flags, _keys = _keys;
- var mask = nBuckets - 1, k = hash(key);
- var i = k & mask;
- var inc = getInc(k, mask); /* inc == 1 for linear probing */
- var last = i;
- while (!flagIsEmpty(flags, i) && (flagIsDel(flags, i) || _keys[i] != key))
- {
- i = (i + inc) & mask;
- if (i == last)
- return -1;
- }
- return isEither(flags, i) ? -1 : i;
- }
- return -1;
- }
- public function get( key : Int ) : Null<T>
- {
- var idx = -1;
- if (cachedKey == key && ( (idx = cachedIndex) != -1 ))
- {
- return vals[idx];
- }
- idx = lookup(key);
- if (idx != -1)
- {
- cachedKey = key;
- cachedIndex = idx;
- return vals[idx];
- }
- return null;
- }
- private function getDefault( key : Int, def : T ) : T
- {
- var idx = -1;
- if (cachedKey == key && ( (idx = cachedIndex) != -1 ))
- {
- return vals[idx];
- }
- idx = lookup(key);
- if (idx != -1)
- {
- cachedKey = key;
- cachedIndex = idx;
- return vals[idx];
- }
- return def;
- }
- public function exists( key : Int ) : Bool
- {
- var idx = -1;
- if (cachedKey == key && ( (idx = cachedIndex) != -1 ))
- {
- return true;
- }
- idx = lookup(key);
- if (idx != -1)
- {
- cachedKey = key;
- cachedIndex = idx;
- return true;
- }
- return false;
- }
- public function remove( key : Int ) : Bool
- {
- var idx = -1;
- if (! (cachedKey == key && ( (idx = cachedIndex) != -1 )))
- {
- idx = lookup(key);
- }
- if (idx == -1)
- {
- return false;
- } else {
- if (cachedKey == key)
- cachedIndex = -1;
- if (!isEither(flags, idx))
- {
- setIsDelTrue(flags, idx);
- --size;
- vals[idx] = null;
- _keys[idx] = 0;
- }
- return true;
- }
- }
- @:final private function resize(newNBuckets:Int) : Void
- {
- //This function uses 0.25*n_bucktes bytes of working space instead of [sizeof(key_t+val_t)+.25]*n_buckets.
- var newFlags = null;
- var j = 1;
- {
- newNBuckets = roundUp(newNBuckets);
- if (newNBuckets < 4) newNBuckets = 4;
- if (size >= (newNBuckets * HASH_UPPER + 0.5)) /* requested size is too small */
- {
- j = 0;
- } else { /* hash table size to be changed (shrink or expand); rehash */
- var nfSize = flagsSize(newNBuckets);
- newFlags = new NativeArray( nfSize );
- for (i in 0...nfSize)
- newFlags[i] = 0xaaaaaaaa;
- if (nBuckets < newNBuckets) //expand
- {
- var k = new NativeArray(newNBuckets);
- if (_keys != null)
- arrayCopy(_keys, 0, k, 0, nBuckets);
- _keys = k;
- var v = new NativeArray(newNBuckets);
- if (vals != null)
- arrayCopy(vals, 0, v, 0, nBuckets);
- vals = v;
- } //otherwise shrink
- }
- }
- if (j != 0)
- { //rehashing is required
- //resetting cache
- cachedKey = 0;
- cachedIndex = -1;
- j = -1;
- var nBuckets = nBuckets, _keys = _keys, vals = vals, flags = flags;
- var newMask = newNBuckets - 1;
- while (++j < nBuckets)
- {
- if (!isEither(flags, j))
- {
- var key = _keys[j];
- var val = vals[j];
- setIsDelTrue(flags, j);
- while (true) /* kick-out process; sort of like in Cuckoo hashing */
- {
- var k = hash(key);
- var inc = getInc(k, newMask);
- var i = k & newMask;
- while (!flagIsEmpty(newFlags, i))
- i = (i + inc) & newMask;
- setIsEmptyFalse(newFlags, i);
- if (i < nBuckets && !isEither(flags, i)) /* kick out the existing element */
- {
- {
- var tmp = _keys[i];
- _keys[i] = key;
- key = tmp;
- }
- {
- var tmp = vals[i];
- vals[i] = val;
- val = tmp;
- }
- setIsDelTrue(flags, i); /* mark it as deleted in the old hash table */
- } else { /* write the element and jump out of the loop */
- _keys[i] = key;
- vals[i] = val;
- break;
- }
- }
- }
- }
- if (nBuckets > newNBuckets) /* shrink the hash table */
- {
- {
- var k = new NativeArray(newNBuckets);
- arrayCopy(_keys, 0, k, 0, newNBuckets);
- this._keys = k;
- }
- {
- var v = new NativeArray(newNBuckets);
- arrayCopy(vals, 0, v, 0, newNBuckets);
- this.vals = v;
- }
- }
- this.flags = newFlags;
- this.nBuckets = newNBuckets;
- this.nOccupied = size;
- this.upperBound = Std.int(newNBuckets * HASH_UPPER + .5);
- }
- }
- /**
- Returns an iterator of all keys in the hashtable.
- Implementation detail: Do not set() any new value while iterating, as it may cause a resize, which will break iteration
- **/
- public function keys() : Iterator<Int>
- {
- var i = 0;
- var len = nBuckets;
- return {
- hasNext: function() {
- for (j in i...len)
- {
- if (!isEither(flags, j))
- {
- i = j;
- return true;
- }
- }
- return false;
- },
- next: function() {
- var ret = _keys[i];
- cachedIndex = i;
- cachedKey = ret;
- i = i + 1;
- return ret;
- }
- };
- }
- /**
- Returns an iterator of all values in the hashtable.
- Implementation detail: Do not set() any new value while iterating, as it may cause a resize, which will break iteration
- **/
- public function iterator() : Iterator<T>
- {
- var i = 0;
- var len = nBuckets;
- return {
- hasNext: function() {
- for (j in i...len)
- {
- if (!isEither(flags, j))
- {
- i = j;
- return true;
- }
- }
- return false;
- },
- next: function() {
- var ret = vals[i];
- i = i + 1;
- return ret;
- }
- };
- }
- /**
- Returns an displayable representation of the hashtable content.
- **/
- public function toString() : String {
- var s = new StringBuf();
- s.add("{");
- var it = keys();
- for( i in it ) {
- s.add(i);
- s.add(" => ");
- s.add(Std.string(get(i)));
- if( it.hasNext() )
- s.add(", ");
- }
- s.add("}");
- return s.toString();
- }
- private static inline function assert(x:Bool):Void
- {
- #if debug
- if (!x) throw "assert failed";
- #end
- }
- private static inline function defaultK():Int return 0
- private static inline function arrayCopy(sourceArray:cs.system.Array, sourceIndex:Int, destinationArray:cs.system.Array, destinationIndex:Int, length:Int):Void
- cs.system.Array.Copy(sourceArray, sourceIndex, destinationArray, destinationIndex, length)
- private static inline function getInc(k:Int, mask:Int):Int
- return (((k) >> 3 ^ (k) << 3) | 1) & (mask)
- private static inline function hash(i:Int):Int
- return i
- private static inline function flagIsEmpty(flag:NativeArray<Int>, i:Int):Bool
- return ( (flag[i >> 4] >>> ((i & 0xf) << 1)) & 2 ) != 0
- private static inline function flagIsDel(flag:NativeArray<Int>, i:Int):Bool
- return ((flag[i >> 4] >>> ((i & 0xf) << 1)) & 1) != 0
- private static inline function isEither(flag:NativeArray<Int>, i:Int):Bool
- return ((flag[i >> 4] >>> ((i & 0xf) << 1)) & 3) != 0
- private static inline function setIsDelFalse(flag:NativeArray<Int>, i:Int):Void
- flag[i >> 4] &= ~(1 << ((i & 0xf) << 1))
- private static inline function setIsEmptyFalse(flag:NativeArray<Int>, i:Int):Void
- flag[i >> 4] &= ~(2 << ((i & 0xf) << 1))
- private static inline function setIsBothFalse(flag:NativeArray<Int>, i:Int):Void
- flag[i >> 4] &= ~(3 << ((i & 0xf) << 1))
- private static inline function setIsDelTrue(flag:NativeArray<Int>, i:Int):Void
- flag[i >> 4] |= 1 << ((i & 0xf) << 1)
- private static inline function roundUp(x:Int):Int
- {
- --x;
- x |= (x) >>> 1;
- x |= (x) >>> 2;
- x |= (x) >>> 4;
- x |= (x) >>> 8;
- x |= (x) >>> 16;
- return ++x;
- }
- private static inline function flagsSize(m:Int):Int
- return ((m) < 16? 1 : (m) >> 4)
- }