X-Git-Url: http://plrg.eecs.uci.edu/git/?p=c11tester.git;a=blobdiff_plain;f=hashtable.h;h=d5c69ccba8456ad4930dcbdee93f3f5d229caca3;hp=e59a995fd92347a361a785a2d5e36c646b1a7656;hb=7966c737f2a88e5e1a56817eb9f6fdaead3eca92;hpb=8b6e648f00b31633f9d72850df82ecdb4dc2699e diff --git a/hashtable.h b/hashtable.h index e59a995f..d5c69ccb 100644 --- a/hashtable.h +++ b/hashtable.h @@ -7,164 +7,197 @@ #include #include - +#include +#include "mymemory.h" +#include "common.h" + +/** + * Hashtable linked node class, for chained storage of hash table conflicts. By + * default it is snapshotting, but you can pass in your own allocation + * functions. + * + * @tparam _Key Type name for the key + * @tparam _Val Type name for the values to be stored + * @tparam _malloc Provide your own 'malloc' for the table, or default to + * snapshotting. + * @tparam _calloc Provide your own 'calloc' for the table, or default to + * snapshotting. + * @tparam _free Provide your own 'free' for the table, or default to + * snapshotting. + */ template - struct hashlistnode { - _Key key; - _Val val; - struct hashlistnode<_Key,_Val> *next; - }; -/** Hashtable class. By default it is snapshotting, but you can pass - in your own allocation functions. */ +struct hashlistnode { + _Key key; + _Val val; +}; -template +/** + * Hashtable class. By default it is snapshotting, but you can pass in your own + * allocation functions. + * + * @tparam _Key Type name for the key + * @tparam _Val Type name for the values to be stored + * @tparam _KeyInt Integer type that is at least as large as _Key. Used for key + * manipulation and storage. + * @tparam _Shift Logical shift to apply to all keys. Default 0. + * @tparam _malloc Provide your own 'malloc' for the table, or default to + * snapshotting. + * @tparam _calloc Provide your own 'calloc' for the table, or default to + * snapshotting. + * @tparam _free Provide your own 'free' for the table, or default to + * snapshotting. + */ +template class HashTable { public: + /** + * Constructor + * @param initialcapacity Sets the initial capacity of the hash table. + * Default size 1024. + * @param factor Sets the percentage full before the hashtable is + * resized. Default ratio 0.5. + */ HashTable(unsigned int initialcapacity=1024, double factor=0.5) { // Allocate space for the hash table - table = (struct hashlistnode<_Key,_Val> **) _calloc(initialcapacity, sizeof(struct hashlistnode<_Key,_Val> *)); + table = (struct hashlistnode<_Key,_Val> *) _calloc(initialcapacity, sizeof(struct hashlistnode<_Key,_Val>)); loadfactor = factor; capacity = initialcapacity; + capacitymask = initialcapacity - 1; + threshold = (unsigned int) (initialcapacity*loadfactor); - mask = (capacity << _Shift)-1; size = 0; // Initial number of elements in the hash } + /** Destructor */ ~HashTable() { - for(unsigned int i=0;i * bin = table[i]; - while(bin!=NULL) { - struct hashlistnode<_Key,_Val> * next=bin->next; - _free(bin); - bin=next; - } - } _free(table); } + /** Override: new operator */ void * operator new(size_t size) { return _malloc(size); } + /** Override: delete operator */ void operator delete(void *p, size_t size) { _free(p); } + /** Override: new[] operator */ void * operator new[](size_t size) { return _malloc(size); } - void operator delete[](void *p, size_t size) {\ + /** Override: delete[] operator */ + void operator delete[](void *p, size_t size) { _free(p); } /** Reset the table to its initial state. */ void reset() { - for(int i=0;i * bin = table[i]; - while(bin!=NULL) { - struct hashlistnode<_Key,_Val> * next=bin->next; - _free(bin); - bin=next; - } - } - memset(table, 0, capacity*sizeof(struct hashlistnode<_Key, _Val> *)); + memset(table, 0, capacity*sizeof(struct hashlistnode<_Key, _Val>)); size=0; } /** Put a key value pair into the table. */ void put(_Key key, _Val val) { - if(size > threshold) { - //Resize - unsigned int newsize = capacity << 1; - resize(newsize); - } + if (size > threshold) + resize(capacity << 1); - struct hashlistnode<_Key,_Val> *ptr = table[(((_KeyInt)key) & mask)>>_Shift]; - size++; - struct hashlistnode<_Key,_Val> *search = ptr; + struct hashlistnode<_Key,_Val> *search; - while(search!=NULL) { + unsigned int index=((_KeyInt)key)>>_Shift; + do { + index=index&capacitymask; + search = &table[index]; if (search->key==key) { search->val=val; return; } - search=search->next; - } - - struct hashlistnode<_Key,_Val> *newptr=(struct hashlistnode<_Key,_Val> *)_malloc(sizeof(struct hashlistnode<_Key,_Val>)); - newptr->key=key; - newptr->val=val; - newptr->next=ptr; - table[(((_KeyInt)key)&mask)>>_Shift]=newptr; + index++; + } while(search->key); + + search->key=key; + search->val=val; + size++; } /** Lookup the corresponding value for the given key. */ _Val get(_Key key) { - struct hashlistnode<_Key,_Val> *search = table[(((_KeyInt)key) & mask)>>_Shift]; + struct hashlistnode<_Key,_Val> *search; - while(search!=NULL) { + unsigned int index=((_KeyInt)key)>>_Shift; + do { + index=index&capacitymask; + search = &table[index]; if (search->key==key) { return search->val; } - search=search->next; - } - return (_Val)0; + index++; + } while(search->key); + return (_Val) 0; } /** Check whether the table contains a value for the given key. */ bool contains(_Key key) { - struct hashlistnode<_Key,_Val> *search = table[(((_KeyInt)key) & mask)>>_Shift]; + struct hashlistnode<_Key,_Val> *search; - while(search!=NULL) { + unsigned int index=((_KeyInt)key)>>_Shift; + do { + index=index&capacitymask; + search = &table[index]; if (search->key==key) { return true; } - search=search->next; - } + index++; + } while(search->key); return false; } /** Resize the table. */ void resize(unsigned int newsize) { - struct hashlistnode<_Key,_Val> ** oldtable = table; - struct hashlistnode<_Key,_Val> ** newtable; + struct hashlistnode<_Key,_Val> * oldtable = table; + struct hashlistnode<_Key,_Val> * newtable; unsigned int oldcapacity = capacity; - if((newtable = (struct hashlistnode<_Key,_Val> **) _calloc(newsize, sizeof(struct hashlistnode<_Key,_Val> *))) == NULL) { - printf("Calloc error %s %d\n", __FILE__, __LINE__); + if((newtable = (struct hashlistnode<_Key,_Val> *) _calloc(newsize, sizeof(struct hashlistnode<_Key,_Val>))) == NULL) { + model_print("Calloc error %s %d\n", __FILE__, __LINE__); exit(-1); } - + table = newtable; //Update the global hashtable upon resize() capacity = newsize; - threshold = (unsigned int) (newsize * loadfactor); - mask = (newsize << _Shift)-1; - - for(unsigned int i = 0; i < oldcapacity; i++) { - struct hashlistnode<_Key, _Val> * bin = oldtable[i]; + capacitymask = newsize - 1; - while(bin!=NULL) { - _Key key=bin->key; - struct hashlistnode<_Key, _Val> * next=bin->next; + threshold = (unsigned int) (newsize * loadfactor); - unsigned int index = (((_KeyInt)key) & mask) >>_Shift; - struct hashlistnode<_Key, _Val> * tmp=newtable[index]; - bin->next=tmp; - newtable[index]=bin; - bin = next; - } + struct hashlistnode<_Key, _Val> * bin = &oldtable[0]; + struct hashlistnode<_Key, _Val> * lastbin = &oldtable[oldcapacity]; + for(; bin < lastbin; bin++) { + _Key key=bin->key; + + struct hashlistnode<_Key,_Val> *search; + + unsigned int index=((_KeyInt)key)>>_Shift; + do { + index=index&capacitymask; + search = &table[index]; + index++; + } while(search->key); + + search->key=key; + search->val=bin->val; } _free(oldtable); //Free the memory of the old hash table } private: - struct hashlistnode<_Key,_Val> **table; + struct hashlistnode<_Key,_Val> *table; unsigned int capacity; - _KeyInt mask; unsigned int size; + unsigned int capacitymask; unsigned int threshold; double loadfactor; };