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stb_ds.h
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stb_ds.h
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/* stb_ds.h - v0.65 - public domain data structures - Sean Barrett 2019 */
#ifdef STBDS_UNIT_TESTS
#define _CRT_SECURE_NO_WARNINGS
#endif
#ifndef INCLUDE_STB_DS_H
#define INCLUDE_STB_DS_H
#include <stddef.h>
#include <string.h>
#ifndef STBDS_NO_SHORT_NAMES
#define arrlen stbds_arrlen
#define arrlenu stbds_arrlenu
#define arrput stbds_arrput
#define arrpush stbds_arrput
#define arrpop stbds_arrpop
#define arrfree stbds_arrfree
#define arraddn stbds_arraddn // deprecated, use one of the following instead:
#define arraddnptr stbds_arraddnptr
#define arraddnindex stbds_arraddnindex
#define arrsetlen stbds_arrsetlen
#define arrlast stbds_arrlast
#define arrins stbds_arrins
#define arrinsn stbds_arrinsn
#define arrdel stbds_arrdel
#define arrdeln stbds_arrdeln
#define arrdelswap stbds_arrdelswap
#define arrcap stbds_arrcap
#define arrsetcap stbds_arrsetcap
#define hmput stbds_hmput
#define hmputs stbds_hmputs
#define hmget stbds_hmget
#define hmget_ts stbds_hmget_ts
#define hmgets stbds_hmgets
#define hmgetp stbds_hmgetp
#define hmgetp_ts stbds_hmgetp_ts
#define hmgetp_null stbds_hmgetp_null
#define hmgeti stbds_hmgeti
#define hmgeti_ts stbds_hmgeti_ts
#define hmdel stbds_hmdel
#define hmlen stbds_hmlen
#define hmlenu stbds_hmlenu
#define hmfree stbds_hmfree
#define hmdefault stbds_hmdefault
#define hmdefaults stbds_hmdefaults
#define shput stbds_shput
#define shputi stbds_shputi
#define shputs stbds_shputs
#define shget stbds_shget
#define shgeti stbds_shgeti
#define shgets stbds_shgets
#define shgetp stbds_shgetp
#define shgetp_null stbds_shgetp_null
#define shdel stbds_shdel
#define shlen stbds_shlen
#define shlenu stbds_shlenu
#define shfree stbds_shfree
#define shdefault stbds_shdefault
#define shdefaults stbds_shdefaults
#define sh_new_arena stbds_sh_new_arena
#define sh_new_strdup stbds_sh_new_strdup
#define stralloc stbds_stralloc
#define strreset stbds_strreset
#endif
#if defined(STBDS_REALLOC) && !defined(STBDS_FREE) || !defined(STBDS_REALLOC) && defined(STBDS_FREE)
#error "You must define both STBDS_REALLOC and STBDS_FREE, or neither."
#endif
#if !defined(STBDS_REALLOC) && !defined(STBDS_FREE)
#include <stdlib.h>
#define STBDS_REALLOC(c,p,s) realloc(p,s)
#define STBDS_FREE(c,p) free(p)
#endif
#ifdef _MSC_VER
#define STBDS_NOTUSED(v) (void)(v)
#else
#define STBDS_NOTUSED(v) (void)sizeof(v)
#endif
#ifdef __cplusplus
extern "C" {
#endif
// for security against attackers, seed the library with a random number, at least time() but stronger is better
extern void stbds_rand_seed(size_t seed);
// these are the hash functions used internally if you want to test them or use them for other purposes
extern size_t stbds_hash_bytes(void *p, size_t len, size_t seed);
extern size_t stbds_hash_string(char *str, size_t seed);
// this is a simple string arena allocator, initialize with e.g. 'stbds_string_arena my_arena={0}'.
typedef struct stbds_string_arena stbds_string_arena;
extern char * stbds_stralloc(stbds_string_arena *a, char *str);
extern void stbds_strreset(stbds_string_arena *a);
// have to #define STBDS_UNIT_TESTS to call this
extern void stbds_unit_tests(void);
///////////////
//
// Everything below here is implementation details
//
extern void * stbds_arrgrowf(void *a, size_t elemsize, size_t addlen, size_t min_cap);
extern void stbds_hmfree_func(void *p, size_t elemsize);
extern void * stbds_hmget_key(void *a, size_t elemsize, void *key, size_t keysize, int mode);
extern void * stbds_hmget_key_ts(void *a, size_t elemsize, void *key, size_t keysize, ptrdiff_t *temp, int mode);
extern void * stbds_hmput_default(void *a, size_t elemsize);
extern void * stbds_hmput_key(void *a, size_t elemsize, void *key, size_t keysize, int mode);
extern void * stbds_hmdel_key(void *a, size_t elemsize, void *key, size_t keysize, size_t keyoffset, int mode);
extern void * stbds_shmode_func(size_t elemsize, int mode);
#ifdef __cplusplus
}
#endif
#if defined(__GNUC__) || defined(__clang__)
#define STBDS_HAS_TYPEOF
#ifdef __cplusplus
//#define STBDS_HAS_LITERAL_ARRAY // this is currently broken for clang
#endif
#endif
#if !defined(__cplusplus)
#if defined(__STDC_VERSION__) && __STDC_VERSION__ >= 199901L
#define STBDS_HAS_LITERAL_ARRAY
#endif
#endif
// this macro takes the address of the argument, but on gcc/clang can accept rvalues
#if defined(STBDS_HAS_LITERAL_ARRAY) && defined(STBDS_HAS_TYPEOF)
#if __clang__
#define STBDS_ADDRESSOF(typevar, value) ((__typeof__(typevar)[1]){value}) // literal array decays to pointer to value
#else
#define STBDS_ADDRESSOF(typevar, value) ((typeof(typevar)[1]){value}) // literal array decays to pointer to value
#endif
#else
#define STBDS_ADDRESSOF(typevar, value) &(value)
#endif
#define STBDS_OFFSETOF(var,field) ((char *) &(var)->field - (char *) (var))
#define stbds_header(t) ((stbds_array_header *) (t) - 1)
#define stbds_temp(t) stbds_header(t)->temp
#define stbds_temp_key(t) (*(char **) stbds_header(t)->hash_table)
#define stbds_arrsetcap(a,n) (stbds_arrgrow(a,0,n))
#define stbds_arrsetlen(a,n) ((stbds_arrcap(a) < (size_t) (n) ? stbds_arrsetcap((a),(size_t)(n)),0 : 0), (a) ? stbds_header(a)->length = (size_t) (n) : 0)
#define stbds_arrcap(a) ((a) ? stbds_header(a)->capacity : 0)
#define stbds_arrlen(a) ((a) ? (ptrdiff_t) stbds_header(a)->length : 0)
#define stbds_arrlenu(a) ((a) ? stbds_header(a)->length : 0)
#define stbds_arrput(a,v) (stbds_arrmaybegrow(a,1), (a)[stbds_header(a)->length++] = (v))
#define stbds_arrpush stbds_arrput // synonym
#define stbds_arrpop(a) (stbds_header(a)->length--, (a)[stbds_header(a)->length])
#define stbds_arraddn(a,n) ((void)(stbds_arraddnoff(a, n))) // deprecated, use one of the following instead:
#define stbds_arraddnptr(a,n) (stbds_arrmaybegrow(a,n), stbds_header(a)->length += (n), &(a)[stbds_header(a)->length-(n)])
#define stbds_arraddnoff(a,n) (stbds_arrmaybegrow(a,n), stbds_header(a)->length += (n), stbds_header(a)->length-(n))
#define stbds_arrlast(a) ((a)[stbds_header(a)->length-1])
#define stbds_arrfree(a) ((void) ((a) ? STBDS_FREE(NULL,stbds_header(a)) : (void)0), (a)=NULL)
#define stbds_arrdel(a,i) stbds_arrdeln(a,i,1)
#define stbds_arrdeln(a,i,n) (memmove(&(a)[i], &(a)[(i)+(n)], sizeof *(a) * (stbds_header(a)->length-(n)-(i))), stbds_header(a)->length -= (n))
#define stbds_arrdelswap(a,i) ((a)[i] = stbds_arrlast(a), stbds_header(a)->length -= 1)
#define stbds_arrinsn(a,i,n) (stbds_arraddn((a),(n)), memmove(&(a)[(i)+(n)], &(a)[i], sizeof *(a) * (stbds_header(a)->length-(n)-(i))))
#define stbds_arrins(a,i,v) (stbds_arrinsn((a),(i),1), (a)[i]=(v))
#define stbds_arrmaybegrow(a,n) ((!(a) || stbds_header(a)->length + (n) > stbds_header(a)->capacity) \
? (stbds_arrgrow(a,n,0),0) : 0)
#define stbds_arrgrow(a,b,c) ((a) = stbds_arrgrowf_wrapper((a), sizeof *(a), (b), (c)))
#define stbds_hmput(t, k, v) \
((t) = stbds_hmput_key_wrapper((t), sizeof *(t), (void*) STBDS_ADDRESSOF((t)->key, (k)), sizeof (t)->key, 0), \
(t)[stbds_temp((t)-1)].key = (k), \
(t)[stbds_temp((t)-1)].value = (v))
#define stbds_hmputs(t, s) \
((t) = stbds_hmput_key_wrapper((t), sizeof *(t), &(s).key, sizeof (s).key, STBDS_HM_BINARY), \
(t)[stbds_temp((t)-1)] = (s))
#define stbds_hmgeti(t,k) \
((t) = stbds_hmget_key_wrapper((t), sizeof *(t), (void*) STBDS_ADDRESSOF((t)->key, (k)), sizeof (t)->key, STBDS_HM_BINARY), \
stbds_temp((t)-1))
#define stbds_hmgeti_ts(t,k,temp) \
((t) = stbds_hmget_key_ts_wrapper((t), sizeof *(t), (void*) STBDS_ADDRESSOF((t)->key, (k)), sizeof (t)->key, &(temp), STBDS_HM_BINARY), \
(temp))
#define stbds_hmgetp(t, k) \
((void) stbds_hmgeti(t,k), &(t)[stbds_temp((t)-1)])
#define stbds_hmgetp_ts(t, k, temp) \
((void) stbds_hmgeti_ts(t,k,temp), &(t)[temp])
#define stbds_hmdel(t,k) \
(((t) = stbds_hmdel_key_wrapper((t),sizeof *(t), (void*) STBDS_ADDRESSOF((t)->key, (k)), sizeof (t)->key, STBDS_OFFSETOF((t),key), STBDS_HM_BINARY)),(t)?stbds_temp((t)-1):0)
#define stbds_hmdefault(t, v) \
((t) = stbds_hmput_default_wrapper((t), sizeof *(t)), (t)[-1].value = (v))
#define stbds_hmdefaults(t, s) \
((t) = stbds_hmput_default_wrapper((t), sizeof *(t)), (t)[-1] = (s))
#define stbds_hmfree(p) \
((void) ((p) != NULL ? stbds_hmfree_func((p)-1,sizeof*(p)),0 : 0),(p)=NULL)
#define stbds_hmgets(t, k) (*stbds_hmgetp(t,k))
#define stbds_hmget(t, k) (stbds_hmgetp(t,k)->value)
#define stbds_hmget_ts(t, k, temp) (stbds_hmgetp_ts(t,k,temp)->value)
#define stbds_hmlen(t) ((t) ? (ptrdiff_t) stbds_header((t)-1)->length-1 : 0)
#define stbds_hmlenu(t) ((t) ? stbds_header((t)-1)->length-1 : 0)
#define stbds_hmgetp_null(t,k) (stbds_hmgeti(t,k) == -1 ? NULL : &(t)[stbds_temp(t)-1])
#define stbds_shput(t, k, v) \
((t) = stbds_hmput_key_wrapper((t), sizeof *(t), (void*) (k), sizeof (t)->key, STBDS_HM_STRING), \
(t)[stbds_temp((t)-1)].value = (v))
#define stbds_shputi(t, k, v) \
((t) = stbds_hmput_key_wrapper((t), sizeof *(t), (void*) (k), sizeof (t)->key, STBDS_HM_STRING), \
(t)[stbds_temp((t)-1)].value = (v), stbds_temp((t)-1))
#define stbds_shputs(t, s) \
((t) = stbds_hmput_key_wrapper((t), sizeof *(t), (void*) (s).key, sizeof (s).key, STBDS_HM_STRING), \
(t)[stbds_temp((t)-1)] = (s), \
(t)[stbds_temp((t)-1)].key = stbds_temp_key((t)-1)) // above line overwrites whole structure, so must rewrite key here if it was allocated internally
#define stbds_pshput(t, p) \
((t) = stbds_hmput_key_wrapper((t), sizeof *(t), (void*) (p)->key, sizeof (p)->key, STBDS_HM_PTR_TO_STRING), \
(t)[stbds_temp((t)-1)] = (p))
#define stbds_shgeti(t,k) \
((t) = stbds_hmget_key_wrapper((t), sizeof *(t), (void*) (k), sizeof (t)->key, STBDS_HM_STRING), \
stbds_temp((t)-1))
#define stbds_pshgeti(t,k) \
((t) = stbds_hmget_key_wrapper((t), sizeof *(t), (void*) (k), sizeof (*(t))->key, STBDS_HM_PTR_TO_STRING), \
stbds_temp((t)-1))
#define stbds_shgetp(t, k) \
((void) stbds_shgeti(t,k), &(t)[stbds_temp((t)-1)])
#define stbds_pshget(t, k) \
((void) stbds_pshgeti(t,k), (t)[stbds_temp((t)-1)])
#define stbds_shdel(t,k) \
(((t) = stbds_hmdel_key_wrapper((t),sizeof *(t), (void*) (k), sizeof (t)->key, STBDS_OFFSETOF((t),key), STBDS_HM_STRING)),(t)?stbds_temp((t)-1):0)
#define stbds_pshdel(t,k) \
(((t) = stbds_hmdel_key_wrapper((t),sizeof *(t), (void*) (k), sizeof (*(t))->key, STBDS_OFFSETOF(*(t),key), STBDS_HM_PTR_TO_STRING)),(t)?stbds_temp((t)-1):0)
#define stbds_sh_new_arena(t) \
((t) = stbds_shmode_func_wrapper(t, sizeof *(t), STBDS_SH_ARENA))
#define stbds_sh_new_strdup(t) \
((t) = stbds_shmode_func_wrapper(t, sizeof *(t), STBDS_SH_STRDUP))
#define stbds_shdefault(t, v) stbds_hmdefault(t,v)
#define stbds_shdefaults(t, s) stbds_hmdefaults(t,s)
#define stbds_shfree stbds_hmfree
#define stbds_shlenu stbds_hmlenu
#define stbds_shgets(t, k) (*stbds_shgetp(t,k))
#define stbds_shget(t, k) (stbds_shgetp(t,k)->value)
#define stbds_shgetp_null(t,k) (stbds_shgeti(t,k) == -1 ? NULL : &(t)[stbds_temp(t)-1])
#define stbds_shlen stbds_hmlen
typedef struct
{
size_t length;
size_t capacity;
void * hash_table;
ptrdiff_t temp;
} stbds_array_header;
typedef struct stbds_string_block
{
struct stbds_string_block *next;
char storage[8];
} stbds_string_block;
struct stbds_string_arena
{
stbds_string_block *storage;
size_t remaining;
unsigned char block;
unsigned char mode; // this isn't used by the string arena itself
};
#define STBDS_HM_BINARY 0
#define STBDS_HM_STRING 1
enum
{
STBDS_SH_NONE,
STBDS_SH_DEFAULT,
STBDS_SH_STRDUP,
STBDS_SH_ARENA
};
#ifdef __cplusplus
// in C we use implicit assignment from these void*-returning functions to T*.
// in C++ these templates make the same code work
template<class T> static T * stbds_arrgrowf_wrapper(T *a, size_t elemsize, size_t addlen, size_t min_cap) {
return (T*)stbds_arrgrowf((void *)a, elemsize, addlen, min_cap);
}
template<class T> static T * stbds_hmget_key_wrapper(T *a, size_t elemsize, void *key, size_t keysize, int mode) {
return (T*)stbds_hmget_key((void*)a, elemsize, key, keysize, mode);
}
template<class T> static T * stbds_hmget_key_ts_wrapper(T *a, size_t elemsize, void *key, size_t keysize, ptrdiff_t *temp, int mode) {
return (T*)stbds_hmget_key_ts((void*)a, elemsize, key, keysize, temp, mode);
}
template<class T> static T * stbds_hmput_default_wrapper(T *a, size_t elemsize) {
return (T*)stbds_hmput_default((void *)a, elemsize);
}
template<class T> static T * stbds_hmput_key_wrapper(T *a, size_t elemsize, void *key, size_t keysize, int mode) {
return (T*)stbds_hmput_key((void*)a, elemsize, key, keysize, mode);
}
template<class T> static T * stbds_hmdel_key_wrapper(T *a, size_t elemsize, void *key, size_t keysize, size_t keyoffset, int mode){
return (T*)stbds_hmdel_key((void*)a, elemsize, key, keysize, keyoffset, mode);
}
template<class T> static T * stbds_shmode_func_wrapper(T *, size_t elemsize, int mode) {
return (T*)stbds_shmode_func(elemsize, mode);
}
#else
#define stbds_arrgrowf_wrapper stbds_arrgrowf
#define stbds_hmget_key_wrapper stbds_hmget_key
#define stbds_hmget_key_ts_wrapper stbds_hmget_key_ts
#define stbds_hmput_default_wrapper stbds_hmput_default
#define stbds_hmput_key_wrapper stbds_hmput_key
#define stbds_hmdel_key_wrapper stbds_hmdel_key
#define stbds_shmode_func_wrapper(t,e,m) stbds_shmode_func(e,m)
#endif
#endif // INCLUDE_STB_DS_H
//////////////////////////////////////////////////////////////////////////////
//
// IMPLEMENTATION
//
#ifdef STB_DS_IMPLEMENTATION
#include <assert.h>
#include <string.h>
#ifndef STBDS_ASSERT
#define STBDS_ASSERT_WAS_UNDEFINED
#define STBDS_ASSERT(x) ((void) 0)
#endif
#ifdef STBDS_STATISTICS
#define STBDS_STATS(x) x
size_t stbds_array_grow;
size_t stbds_hash_grow;
size_t stbds_hash_shrink;
size_t stbds_hash_rebuild;
size_t stbds_hash_probes;
size_t stbds_hash_alloc;
size_t stbds_rehash_probes;
size_t stbds_rehash_items;
#else
#define STBDS_STATS(x)
#endif
//
// stbds_arr implementation
//
//int *prev_allocs[65536];
//int num_prev;
void *stbds_arrgrowf(void *a, size_t elemsize, size_t addlen, size_t min_cap)
{
void *b;
size_t min_len = stbds_arrlen(a) + addlen;
// compute the minimum capacity needed
if (min_len > min_cap)
min_cap = min_len;
if (min_cap <= stbds_arrcap(a))
return a;
// increase needed capacity to guarantee O(1) amortized
if (min_cap < 2 * stbds_arrcap(a))
min_cap = 2 * stbds_arrcap(a);
else if (min_cap < 4)
min_cap = 4;
//if (num_prev < 65536) if (a) prev_allocs[num_prev++] = (int *) ((char *) a+1);
//if (num_prev == 2201)
// num_prev = num_prev;
b = STBDS_REALLOC(NULL, (a) ? stbds_header(a) : 0, elemsize * min_cap + sizeof(stbds_array_header));
//if (num_prev < 65536) prev_allocs[num_prev++] = (int *) (char *) b;
b = (char *) b + sizeof(stbds_array_header);
if (a == NULL) {
stbds_header(b)->length = 0;
stbds_header(b)->hash_table = 0;
} else {
STBDS_STATS(++stbds_array_grow);
}
stbds_header(b)->capacity = min_cap;
return b;
}
//
// stbds_hm hash table implementation
//
#ifdef STBDS_INTERNAL_SMALL_BUCKET
#define STBDS_BUCKET_LENGTH 4
#else
#define STBDS_BUCKET_LENGTH 8
#endif
#define STBDS_BUCKET_SHIFT (STBDS_BUCKET_LENGTH == 8 ? 3 : 2)
#define STBDS_BUCKET_MASK (STBDS_BUCKET_LENGTH-1)
#define STBDS_CACHE_LINE_SIZE 64
#define STBDS_ALIGN_FWD(n,a) (((n) + (a) - 1) & ~((a)-1))
typedef struct
{
size_t hash [STBDS_BUCKET_LENGTH];
ptrdiff_t index[STBDS_BUCKET_LENGTH];
} stbds_hash_bucket; // in 32-bit, this is one 64-byte cache line; in 64-bit, each array is one 64-byte cache line
typedef struct
{
char * temp_key; // this MUST be the first field of the hash table
size_t slot_count;
size_t used_count;
size_t used_count_threshold;
size_t used_count_shrink_threshold;
size_t tombstone_count;
size_t tombstone_count_threshold;
size_t seed;
size_t slot_count_log2;
stbds_string_arena string;
stbds_hash_bucket *storage; // not a separate allocation, just 64-byte aligned storage after this struct
} stbds_hash_index;
#define STBDS_INDEX_EMPTY -1
#define STBDS_INDEX_DELETED -2
#define STBDS_INDEX_IN_USE(x) ((x) >= 0)
#define STBDS_HASH_EMPTY 0
#define STBDS_HASH_DELETED 1
static size_t stbds_hash_seed=0x31415926;
void stbds_rand_seed(size_t seed)
{
stbds_hash_seed = seed;
}
#define stbds_load_32_or_64(var, temp, v32, v64_hi, v64_lo) \
temp = v64_lo ^ v32, temp <<= 16, temp <<= 16, temp >>= 16, temp >>= 16, /* discard if 32-bit */ \
var = v64_hi, var <<= 16, var <<= 16, /* discard if 32-bit */ \
var ^= temp ^ v32
#define STBDS_SIZE_T_BITS ((sizeof (size_t)) * 8)
static size_t stbds_probe_position(size_t hash, size_t slot_count, size_t slot_log2)
{
size_t pos;
STBDS_NOTUSED(slot_log2);
pos = hash & (slot_count-1);
#ifdef STBDS_INTERNAL_BUCKET_START
pos &= ~STBDS_BUCKET_MASK;
#endif
return pos;
}
static size_t stbds_log2(size_t slot_count)
{
size_t n=0;
while (slot_count > 1) {
slot_count >>= 1;
++n;
}
return n;
}
static stbds_hash_index *stbds_make_hash_index(size_t slot_count, stbds_hash_index *ot)
{
stbds_hash_index *t;
t = (stbds_hash_index *) STBDS_REALLOC(NULL,0,(slot_count >> STBDS_BUCKET_SHIFT) * sizeof(stbds_hash_bucket) + sizeof(stbds_hash_index) + STBDS_CACHE_LINE_SIZE-1);
t->storage = (stbds_hash_bucket *) STBDS_ALIGN_FWD((size_t) (t+1), STBDS_CACHE_LINE_SIZE);
t->slot_count = slot_count;
t->slot_count_log2 = stbds_log2(slot_count);
t->tombstone_count = 0;
t->used_count = 0;
#if 0 // A1
t->used_count_threshold = slot_count*12/16; // if 12/16th of table is occupied, grow
t->tombstone_count_threshold = slot_count* 2/16; // if tombstones are 2/16th of table, rebuild
t->used_count_shrink_threshold = slot_count* 4/16; // if table is only 4/16th full, shrink
#elif 1 // A2
//t->used_count_threshold = slot_count*12/16; // if 12/16th of table is occupied, grow
//t->tombstone_count_threshold = slot_count* 3/16; // if tombstones are 3/16th of table, rebuild
//t->used_count_shrink_threshold = slot_count* 4/16; // if table is only 4/16th full, shrink
// compute without overflowing
t->used_count_threshold = slot_count - (slot_count>>2);
t->tombstone_count_threshold = (slot_count>>3) + (slot_count>>4);
t->used_count_shrink_threshold = slot_count >> 2;
#elif 0 // B1
t->used_count_threshold = slot_count*13/16; // if 13/16th of table is occupied, grow
t->tombstone_count_threshold = slot_count* 2/16; // if tombstones are 2/16th of table, rebuild
t->used_count_shrink_threshold = slot_count* 5/16; // if table is only 5/16th full, shrink
#else // C1
t->used_count_threshold = slot_count*14/16; // if 14/16th of table is occupied, grow
t->tombstone_count_threshold = slot_count* 2/16; // if tombstones are 2/16th of table, rebuild
t->used_count_shrink_threshold = slot_count* 6/16; // if table is only 6/16th full, shrink
#endif
// Following statistics were measured on a Core i7-6700 @ 4.00Ghz, compiled with clang 7.0.1 -O2
// Note that the larger tables have high variance as they were run fewer times
// A1 A2 B1 C1
// 0.10ms : 0.10ms : 0.10ms : 0.11ms : 2,000 inserts creating 2K table
// 0.96ms : 0.95ms : 0.97ms : 1.04ms : 20,000 inserts creating 20K table
// 14.48ms : 14.46ms : 10.63ms : 11.00ms : 200,000 inserts creating 200K table
// 195.74ms : 196.35ms : 203.69ms : 214.92ms : 2,000,000 inserts creating 2M table
// 2193.88ms : 2209.22ms : 2285.54ms : 2437.17ms : 20,000,000 inserts creating 20M table
// 65.27ms : 53.77ms : 65.33ms : 65.47ms : 500,000 inserts & deletes in 2K table
// 72.78ms : 62.45ms : 71.95ms : 72.85ms : 500,000 inserts & deletes in 20K table
// 89.47ms : 77.72ms : 96.49ms : 96.75ms : 500,000 inserts & deletes in 200K table
// 97.58ms : 98.14ms : 97.18ms : 97.53ms : 500,000 inserts & deletes in 2M table
// 118.61ms : 119.62ms : 120.16ms : 118.86ms : 500,000 inserts & deletes in 20M table
// 192.11ms : 194.39ms : 196.38ms : 195.73ms : 500,000 inserts & deletes in 200M table
if (slot_count <= STBDS_BUCKET_LENGTH)
t->used_count_shrink_threshold = 0;
// to avoid infinite loop, we need to guarantee that at least one slot is empty and will terminate probes
STBDS_ASSERT(t->used_count_threshold + t->tombstone_count_threshold < t->slot_count);
STBDS_STATS(++stbds_hash_alloc);
if (ot) {
t->string = ot->string;
// reuse old seed so we can reuse old hashes so below "copy out old data" doesn't do any hashing
t->seed = ot->seed;
} else {
size_t a,b,temp;
memset(&t->string, 0, sizeof(t->string));
t->seed = stbds_hash_seed;
// LCG
// in 32-bit, a = 2147001325 b = 715136305
// in 64-bit, a = 2862933555777941757 b = 3037000493
stbds_load_32_or_64(a,temp, 2147001325, 0x27bb2ee6, 0x87b0b0fd);
stbds_load_32_or_64(b,temp, 715136305, 0, 0xb504f32d);
stbds_hash_seed = stbds_hash_seed * a + b;
}
{
size_t i,j;
for (i=0; i < slot_count >> STBDS_BUCKET_SHIFT; ++i) {
stbds_hash_bucket *b = &t->storage[i];
for (j=0; j < STBDS_BUCKET_LENGTH; ++j)
b->hash[j] = STBDS_HASH_EMPTY;
for (j=0; j < STBDS_BUCKET_LENGTH; ++j)
b->index[j] = STBDS_INDEX_EMPTY;
}
}
// copy out the old data, if any
if (ot) {
size_t i,j;
t->used_count = ot->used_count;
for (i=0; i < ot->slot_count >> STBDS_BUCKET_SHIFT; ++i) {
stbds_hash_bucket *ob = &ot->storage[i];
for (j=0; j < STBDS_BUCKET_LENGTH; ++j) {
if (STBDS_INDEX_IN_USE(ob->index[j])) {
size_t hash = ob->hash[j];
size_t pos = stbds_probe_position(hash, t->slot_count, t->slot_count_log2);
size_t step = STBDS_BUCKET_LENGTH;
STBDS_STATS(++stbds_rehash_items);
for (;;) {
size_t limit,z;
stbds_hash_bucket *bucket;
bucket = &t->storage[pos >> STBDS_BUCKET_SHIFT];
STBDS_STATS(++stbds_rehash_probes);
for (z=pos & STBDS_BUCKET_MASK; z < STBDS_BUCKET_LENGTH; ++z) {
if (bucket->hash[z] == 0) {
bucket->hash[z] = hash;
bucket->index[z] = ob->index[j];
goto done;
}
}
limit = pos & STBDS_BUCKET_MASK;
for (z = 0; z < limit; ++z) {
if (bucket->hash[z] == 0) {
bucket->hash[z] = hash;
bucket->index[z] = ob->index[j];
goto done;
}
}
pos += step; // quadratic probing
step += STBDS_BUCKET_LENGTH;
pos &= (t->slot_count-1);
}
}
done:
;
}
}
}
return t;
}
#define STBDS_ROTATE_LEFT(val, n) (((val) << (n)) | ((val) >> (STBDS_SIZE_T_BITS - (n))))
#define STBDS_ROTATE_RIGHT(val, n) (((val) >> (n)) | ((val) << (STBDS_SIZE_T_BITS - (n))))
size_t stbds_hash_string(char *str, size_t seed)
{
size_t hash = seed;
while (*str)
hash = STBDS_ROTATE_LEFT(hash, 9) + (unsigned char) *str++;
// Thomas Wang 64-to-32 bit mix function, hopefully also works in 32 bits
hash ^= seed;
hash = (~hash) + (hash << 18);
hash ^= hash ^ STBDS_ROTATE_RIGHT(hash,31);
hash = hash * 21;
hash ^= hash ^ STBDS_ROTATE_RIGHT(hash,11);
hash += (hash << 6);
hash ^= STBDS_ROTATE_RIGHT(hash,22);
return hash+seed;
}
#ifdef STBDS_SIPHASH_2_4
#define STBDS_SIPHASH_C_ROUNDS 2
#define STBDS_SIPHASH_D_ROUNDS 4
typedef int STBDS_SIPHASH_2_4_can_only_be_used_in_64_bit_builds[sizeof(size_t) == 8 ? 1 : -1];
#endif
#ifndef STBDS_SIPHASH_C_ROUNDS
#define STBDS_SIPHASH_C_ROUNDS 1
#endif
#ifndef STBDS_SIPHASH_D_ROUNDS
#define STBDS_SIPHASH_D_ROUNDS 1
#endif
#ifdef _MSC_VER
#pragma warning(push)
#pragma warning(disable:4127) // conditional expression is constant, for do..while(0) and sizeof()==
#endif
static size_t stbds_siphash_bytes(void *p, size_t len, size_t seed)
{
unsigned char *d = (unsigned char *) p;
size_t i,j;
size_t v0,v1,v2,v3, data;
// hash that works on 32- or 64-bit registers without knowing which we have
// (computes different results on 32-bit and 64-bit platform)
// derived from siphash, but on 32-bit platforms very different as it uses 4 32-bit state not 4 64-bit
v0 = ((((size_t) 0x736f6d65 << 16) << 16) + 0x70736575) ^ seed;
v1 = ((((size_t) 0x646f7261 << 16) << 16) + 0x6e646f6d) ^ ~seed;
v2 = ((((size_t) 0x6c796765 << 16) << 16) + 0x6e657261) ^ seed;
v3 = ((((size_t) 0x74656462 << 16) << 16) + 0x79746573) ^ ~seed;
#ifdef STBDS_TEST_SIPHASH_2_4
// hardcoded with key material in the siphash test vectors
v0 ^= 0x0706050403020100ull ^ seed;
v1 ^= 0x0f0e0d0c0b0a0908ull ^ ~seed;
v2 ^= 0x0706050403020100ull ^ seed;
v3 ^= 0x0f0e0d0c0b0a0908ull ^ ~seed;
#endif
#define STBDS_SIPROUND() \
do { \
v0 += v1; v1 = STBDS_ROTATE_LEFT(v1, 13); v1 ^= v0; v0 = STBDS_ROTATE_LEFT(v0,STBDS_SIZE_T_BITS/2); \
v2 += v3; v3 = STBDS_ROTATE_LEFT(v3, 16); v3 ^= v2; \
v2 += v1; v1 = STBDS_ROTATE_LEFT(v1, 17); v1 ^= v2; v2 = STBDS_ROTATE_LEFT(v2,STBDS_SIZE_T_BITS/2); \
v0 += v3; v3 = STBDS_ROTATE_LEFT(v3, 21); v3 ^= v0; \
} while (0)
for (i=0; i+sizeof(size_t) <= len; i += sizeof(size_t), d += sizeof(size_t)) {
data = d[0] | (d[1] << 8) | (d[2] << 16) | (d[3] << 24);
data |= (size_t) (d[4] | (d[5] << 8) | (d[6] << 16) | (d[7] << 24)) << 16 << 16; // discarded if size_t == 4
v3 ^= data;
for (j=0; j < STBDS_SIPHASH_C_ROUNDS; ++j)
STBDS_SIPROUND();
v0 ^= data;
}
data = len << (STBDS_SIZE_T_BITS-8);
switch (len - i) {
case 7: data |= ((size_t) d[6] << 24) << 24; // fall through
case 6: data |= ((size_t) d[5] << 20) << 20; // fall through
case 5: data |= ((size_t) d[4] << 16) << 16; // fall through
case 4: data |= (d[3] << 24); // fall through
case 3: data |= (d[2] << 16); // fall through
case 2: data |= (d[1] << 8); // fall through
case 1: data |= d[0]; // fall through
case 0: break;
}
v3 ^= data;
for (j=0; j < STBDS_SIPHASH_C_ROUNDS; ++j)
STBDS_SIPROUND();
v0 ^= data;
v2 ^= 0xff;
for (j=0; j < STBDS_SIPHASH_D_ROUNDS; ++j)
STBDS_SIPROUND();
#ifdef STBDS_SIPHASH_2_4
return v0^v1^v2^v3;
#else
return v1^v2^v3; // slightly stronger since v0^v3 in above cancels out final round operation? I tweeted at the authors of SipHash about this but they didn't reply
#endif
}
size_t stbds_hash_bytes(void *p, size_t len, size_t seed)
{
#ifdef STBDS_SIPHASH_2_4
return stbds_siphash_bytes(p,len,seed);
#else
unsigned char *d = (unsigned char *) p;
if (len == 4) {
unsigned int hash = d[0] | (d[1] << 8) | (d[2] << 16) | (d[3] << 24);
#if 0
// HASH32-A Bob Jenkin's hash function w/o large constants
hash ^= seed;
hash -= (hash<<6);
hash ^= (hash>>17);
hash -= (hash<<9);
hash ^= seed;
hash ^= (hash<<4);
hash -= (hash<<3);
hash ^= (hash<<10);
hash ^= (hash>>15);
#elif 1
// HASH32-BB Bob Jenkin's presumably-accidental version of Thomas Wang hash with rotates turned into shifts.
// Note that converting these back to rotates makes it run a lot slower, presumably due to collisions, so I'm
// not really sure what's going on.
hash ^= seed;
hash = (hash ^ 61) ^ (hash >> 16);
hash = hash + (hash << 3);
hash = hash ^ (hash >> 4);
hash = hash * 0x27d4eb2d;
hash ^= seed;
hash = hash ^ (hash >> 15);
#else // HASH32-C - Murmur3
hash ^= seed;
hash *= 0xcc9e2d51;
hash = (hash << 17) | (hash >> 15);
hash *= 0x1b873593;
hash ^= seed;
hash = (hash << 19) | (hash >> 13);
hash = hash*5 + 0xe6546b64;
hash ^= hash >> 16;
hash *= 0x85ebca6b;
hash ^= seed;
hash ^= hash >> 13;
hash *= 0xc2b2ae35;
hash ^= hash >> 16;
#endif
// Following statistics were measured on a Core i7-6700 @ 4.00Ghz, compiled with clang 7.0.1 -O2
// Note that the larger tables have high variance as they were run fewer times
// HASH32-A // HASH32-BB // HASH32-C
// 0.10ms // 0.10ms // 0.10ms : 2,000 inserts creating 2K table
// 0.96ms // 0.95ms // 0.99ms : 20,000 inserts creating 20K table
// 14.69ms // 14.43ms // 14.97ms : 200,000 inserts creating 200K table
// 199.99ms // 195.36ms // 202.05ms : 2,000,000 inserts creating 2M table
// 2234.84ms // 2187.74ms // 2240.38ms : 20,000,000 inserts creating 20M table
// 55.68ms // 53.72ms // 57.31ms : 500,000 inserts & deletes in 2K table
// 63.43ms // 61.99ms // 65.73ms : 500,000 inserts & deletes in 20K table
// 80.04ms // 77.96ms // 81.83ms : 500,000 inserts & deletes in 200K table
// 100.42ms // 97.40ms // 102.39ms : 500,000 inserts & deletes in 2M table
// 119.71ms // 120.59ms // 121.63ms : 500,000 inserts & deletes in 20M table
// 185.28ms // 195.15ms // 187.74ms : 500,000 inserts & deletes in 200M table
// 15.58ms // 14.79ms // 15.52ms : 200,000 inserts creating 200K table with varying key spacing
return (((size_t) hash << 16 << 16) | hash) ^ seed;
} else if (len == 8 && sizeof(size_t) == 8) {
size_t hash = d[0] | (d[1] << 8) | (d[2] << 16) | (d[3] << 24);
hash |= (size_t) (d[4] | (d[5] << 8) | (d[6] << 16) | (d[7] << 24)) << 16 << 16; // avoid warning if size_t == 4
hash ^= seed;
hash = (~hash) + (hash << 21);
hash ^= STBDS_ROTATE_RIGHT(hash,24);
hash *= 265;
hash ^= STBDS_ROTATE_RIGHT(hash,14);
hash ^= seed;
hash *= 21;
hash ^= STBDS_ROTATE_RIGHT(hash,28);
hash += (hash << 31);
hash = (~hash) + (hash << 18);
return hash;
} else {
return stbds_siphash_bytes(p,len,seed);
}
#endif
}
#ifdef _MSC_VER
#pragma warning(pop)
#endif
static int stbds_is_key_equal(void *a, size_t elemsize, void *key, size_t keysize, size_t keyoffset, int mode, size_t i)
{
if (mode >= STBDS_HM_STRING)
return 0==strcmp((char *) key, * (char **) ((char *) a + elemsize*i + keyoffset));
else
return 0==memcmp(key, (char *) a + elemsize*i + keyoffset, keysize);
}
#define STBDS_HASH_TO_ARR(x,elemsize) ((char*) (x) - (elemsize))
#define STBDS_ARR_TO_HASH(x,elemsize) ((char*) (x) + (elemsize))
#define stbds_hash_table(a) ((stbds_hash_index *) stbds_header(a)->hash_table)
void stbds_hmfree_func(void *a, size_t elemsize)
{
if (a == NULL) return;
if (stbds_hash_table(a) != NULL) {
if (stbds_hash_table(a)->string.mode == STBDS_SH_STRDUP) {
size_t i;
// skip 0th element, which is default
for (i=1; i < stbds_header(a)->length; ++i)
STBDS_FREE(NULL, *(char**) ((char *) a + elemsize*i));
}
stbds_strreset(&stbds_hash_table(a)->string);
}
STBDS_FREE(NULL, stbds_header(a)->hash_table);
STBDS_FREE(NULL, stbds_header(a));
}
static ptrdiff_t stbds_hm_find_slot(void *a, size_t elemsize, void *key, size_t keysize, size_t keyoffset, int mode)
{
void *raw_a = STBDS_HASH_TO_ARR(a,elemsize);
stbds_hash_index *table = stbds_hash_table(raw_a);
size_t hash = mode >= STBDS_HM_STRING ? stbds_hash_string((char*)key,table->seed) : stbds_hash_bytes(key, keysize,table->seed);
size_t step = STBDS_BUCKET_LENGTH;
size_t limit,i;
size_t pos;
stbds_hash_bucket *bucket;
if (hash < 2) hash += 2; // stored hash values are forbidden from being 0, so we can detect empty slots
pos = stbds_probe_position(hash, table->slot_count, table->slot_count_log2);
for (;;) {
STBDS_STATS(++stbds_hash_probes);
bucket = &table->storage[pos >> STBDS_BUCKET_SHIFT];
// start searching from pos to end of bucket, this should help performance on small hash tables that fit in cache
for (i=pos & STBDS_BUCKET_MASK; i < STBDS_BUCKET_LENGTH; ++i) {
if (bucket->hash[i] == hash) {
if (stbds_is_key_equal(a, elemsize, key, keysize, keyoffset, mode, bucket->index[i])) {
return (pos & ~STBDS_BUCKET_MASK)+i;
}
} else if (bucket->hash[i] == STBDS_HASH_EMPTY) {
return -1;
}
}
// search from beginning of bucket to pos
limit = pos & STBDS_BUCKET_MASK;
for (i = 0; i < limit; ++i) {
if (bucket->hash[i] == hash) {
if (stbds_is_key_equal(a, elemsize, key, keysize, keyoffset, mode, bucket->index[i])) {
return (pos & ~STBDS_BUCKET_MASK)+i;
}
} else if (bucket->hash[i] == STBDS_HASH_EMPTY) {
return -1;
}
}
// quadratic probing
pos += step;
step += STBDS_BUCKET_LENGTH;
pos &= (table->slot_count-1);
}
/* NOTREACHED */
}
void * stbds_hmget_key_ts(void *a, size_t elemsize, void *key, size_t keysize, ptrdiff_t *temp, int mode)
{
size_t keyoffset = 0;
if (a == NULL) {
// make it non-empty so we can return a temp
a = stbds_arrgrowf(0, elemsize, 0, 1);
stbds_header(a)->length += 1;
memset(a, 0, elemsize);
*temp = STBDS_INDEX_EMPTY;
// adjust a to point after the default element
return STBDS_ARR_TO_HASH(a,elemsize);
} else {
stbds_hash_index *table;
void *raw_a = STBDS_HASH_TO_ARR(a,elemsize);
// adjust a to point to the default element
table = (stbds_hash_index *) stbds_header(raw_a)->hash_table;
if (table == 0) {
*temp = -1;
} else {
ptrdiff_t slot = stbds_hm_find_slot(a, elemsize, key, keysize, keyoffset, mode);
if (slot < 0) {
*temp = STBDS_INDEX_EMPTY;
} else {
stbds_hash_bucket *b = &table->storage[slot >> STBDS_BUCKET_SHIFT];
*temp = b->index[slot & STBDS_BUCKET_MASK];
}
}
return a;
}
}
void * stbds_hmget_key(void *a, size_t elemsize, void *key, size_t keysize, int mode)
{
ptrdiff_t temp;
void *p = stbds_hmget_key_ts(a, elemsize, key, keysize, &temp, mode);
stbds_temp(STBDS_HASH_TO_ARR(p,elemsize)) = temp;
return p;
}
void * stbds_hmput_default(void *a, size_t elemsize)
{
// three cases:
// a is NULL <- allocate
// a has a hash table but no entries, because of shmode <- grow
// a has entries <- do nothing
if (a == NULL || stbds_header(STBDS_HASH_TO_ARR(a,elemsize))->length == 0) {
a = stbds_arrgrowf(a ? STBDS_HASH_TO_ARR(a,elemsize) : NULL, elemsize, 0, 1);
stbds_header(a)->length += 1;
memset(a, 0, elemsize);
a=STBDS_ARR_TO_HASH(a,elemsize);
}
return a;
}
static char *stbds_strdup(char *str);
void *stbds_hmput_key(void *a, size_t elemsize, void *key, size_t keysize, int mode)
{
size_t keyoffset=0;
void *raw_a;
stbds_hash_index *table;
if (a == NULL) {
a = stbds_arrgrowf(0, elemsize, 0, 1);
memset(a, 0, elemsize);
stbds_header(a)->length += 1;
// adjust a to point AFTER the default element
a = STBDS_ARR_TO_HASH(a,elemsize);
}
// adjust a to point to the default element
raw_a = a;
a = STBDS_HASH_TO_ARR(a,elemsize);
table = (stbds_hash_index *) stbds_header(a)->hash_table;
if (table == NULL || table->used_count >= table->used_count_threshold) {
stbds_hash_index *nt;
size_t slot_count;
slot_count = (table == NULL) ? STBDS_BUCKET_LENGTH : table->slot_count*2;
nt = stbds_make_hash_index(slot_count, table);
if (table)
STBDS_FREE(NULL, table);
else
nt->string.mode = mode >= STBDS_HM_STRING ? STBDS_SH_DEFAULT : 0;
stbds_header(a)->hash_table = table = nt;
STBDS_STATS(++stbds_hash_grow);
}
// we iterate hash table explicitly because we want to track if we saw a tombstone
{
size_t hash = mode >= STBDS_HM_STRING ? stbds_hash_string((char*)key,table->seed) : stbds_hash_bytes(key, keysize,table->seed);
size_t step = STBDS_BUCKET_LENGTH;
size_t limit,i;
size_t pos;
ptrdiff_t tombstone = -1;
stbds_hash_bucket *bucket;
// stored hash values are forbidden from being 0, so we can detect empty slots to early out quickly
if (hash < 2) hash += 2;
pos = stbds_probe_position(hash, table->slot_count, table->slot_count_log2);
for (;;) {
STBDS_STATS(++stbds_hash_probes);
bucket = &table->storage[pos >> STBDS_BUCKET_SHIFT];
// start searching from pos to end of bucket
for (i=pos & STBDS_BUCKET_MASK; i < STBDS_BUCKET_LENGTH; ++i) {
if (bucket->hash[i] == hash) {
if (stbds_is_key_equal(raw_a, elemsize, key, keysize, keyoffset, mode, bucket->index[i])) {
stbds_temp(a) = bucket->index[i];