-
Notifications
You must be signed in to change notification settings - Fork 13
/
htable.inc
148 lines (144 loc) · 10.1 KB
/
htable.inc
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
//-*- mode:c -*-
/*
include this file and call HTIMPL to generate an implementation
*/
#define hash_size(h) ((h)->size/2)
// compute empirical max-probe for a given size
#define max_probe(size) ((size)<=(HT_N_INLINE*2) ? (HT_N_INLINE/2) : (size)>>3)
#define HTIMPL(HTNAME, HFUNC, EQFUNC) \
static void **HTNAME##_lookup_bp(htable_t *h, void *key) \
{ \
uint_t hv; \
size_t i, orig, index, iter; \
size_t newsz, sz = hash_size(h); \
size_t maxprobe = max_probe(sz); \
void **tab = h->table; \
void **ol; \
\
hv = HFUNC((uptrint_t)key); \
retry_bp: \
iter = 0; \
index = (index_t)(hv & (sz-1)) * 2; \
sz *= 2; \
orig = index; \
\
do { \
if (tab[index+1] == HT_NOTFOUND) { \
tab[index] = key; \
return &tab[index+1]; \
} \
\
if (EQFUNC(key, tab[index])) \
return &tab[index+1]; \
\
index = (index+2) & (sz-1); \
iter++; \
if (iter > maxprobe) \
break; \
} while (index != orig); \
\
/* table full */ \
/* quadruple size, rehash, retry the insert */ \
/* it's important to grow the table really fast; otherwise we waste */ \
/* lots of time rehashing all the keys over and over. */ \
sz = h->size; \
ol = h->table; \
if (sz >= (1<<19) || (sz <= (1<<8))) \
newsz = sz<<1; \
else if (sz <= HT_N_INLINE) \
newsz = HT_N_INLINE; \
else \
newsz = sz<<2; \
/*printf("trying to allocate %d words.\n", newsz); fflush(stdout);*/ \
tab = (void**)LLT_ALLOC(newsz*sizeof(void*)); \
if (tab == NULL) \
return NULL; \
for(i=0; i < newsz; i++) \
tab[i] = HT_NOTFOUND; \
h->table = tab; \
h->size = newsz; \
for(i=0; i < sz; i+=2) { \
if (ol[i+1] != HT_NOTFOUND) { \
(*HTNAME##_lookup_bp(h, ol[i])) = ol[i+1]; \
} \
} \
if (ol != &h->_space[0]) \
LLT_FREE(ol); \
\
sz = hash_size(h); \
maxprobe = max_probe(sz); \
tab = h->table; \
\
goto retry_bp; \
\
return NULL; \
} \
\
void HTNAME##_put(htable_t *h, void *key, void *val) \
{ \
void **bp = HTNAME##_lookup_bp(h, key); \
\
*bp = val; \
} \
\
void **HTNAME##_bp(htable_t *h, void *key) \
{ \
return HTNAME##_lookup_bp(h, key); \
} \
\
/* returns bp if key is in hash, otherwise NULL */ \
/* if return is non-NULL and *bp == HT_NOTFOUND then key was deleted */ \
static void **HTNAME##_peek_bp(htable_t *h, void *key) \
{ \
size_t sz = hash_size(h); \
size_t maxprobe = max_probe(sz); \
void **tab = h->table; \
size_t index = (index_t)(HFUNC((uptrint_t)key) & (sz-1)) * 2; \
sz *= 2; \
size_t orig = index; \
size_t iter = 0; \
\
do { \
if (tab[index] == HT_NOTFOUND) \
return NULL; \
if (EQFUNC(key, tab[index])) \
return &tab[index+1]; \
\
index = (index+2) & (sz-1); \
iter++; \
if (iter > maxprobe) \
break; \
} while (index != orig); \
\
return NULL; \
} \
\
void *HTNAME##_get(htable_t *h, void *key) \
{ \
void **bp = HTNAME##_peek_bp(h, key); \
if (bp == NULL) \
return HT_NOTFOUND; \
return *bp; \
} \
\
int HTNAME##_has(htable_t *h, void *key) \
{ \
return (HTNAME##_get(h,key) != HT_NOTFOUND); \
} \
\
int HTNAME##_remove(htable_t *h, void *key) \
{ \
void **bp = HTNAME##_peek_bp(h, key); \
if (bp != NULL) { \
*bp = HT_NOTFOUND; \
return 1; \
} \
return 0; \
} \
\
void HTNAME##_adjoin(htable_t *h, void *key, void *val) \
{ \
void **bp = HTNAME##_lookup_bp(h, key); \
if (*bp == HT_NOTFOUND) \
*bp = val; \
}