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
|
/*
* (c)2014 Tweag I/O
*
* The Static Pointer Table implementation.
*
* https://ghc.haskell.org/trac/ghc/wiki/StaticPointers
* https://ghc.haskell.org/trac/ghc/wiki/StaticPointers/ImplementationPlan
*
*/
#include "StaticPtrTable.h"
#include "Rts.h"
#include "RtsUtils.h"
#include "Hash.h"
#include "StablePtr.h"
static HashTable * spt = NULL;
#if defined(THREADED_RTS)
static Mutex spt_lock;
#endif
/// Hash function for the SPT.
static int hashFingerprint(const HashTable *table, StgWord key) {
const StgWord64* ptr = (StgWord64*) key;
// Take half of the key to compute the hash.
return hashWord(table, *(ptr + 1));
}
/// Comparison function for the SPT.
static int compareFingerprint(StgWord a, StgWord b) {
const StgWord64* ptra = (StgWord64*) a;
const StgWord64* ptrb = (StgWord64*) b;
return *ptra == *ptrb && *(ptra + 1) == *(ptrb + 1);
}
void hs_spt_insert_stableptr(StgWord64 key[2], StgStablePtr *entry) {
// hs_spt_insert is called from constructor functions, so
// the SPT needs to be initialized here.
if (spt == NULL) {
spt = allocHashTable_(hashFingerprint, compareFingerprint);
#if defined(THREADED_RTS)
initMutex(&spt_lock);
#endif
}
ACQUIRE_LOCK(&spt_lock);
insertHashTable(spt, (StgWord)key, entry);
RELEASE_LOCK(&spt_lock);
}
void hs_spt_insert(StgWord64 key[2], void *spe_closure) {
// Cannot remove this indirection yet because getStablePtr()
// might return NULL, in which case hs_spt_lookup() returns NULL
// instead of the actual closure pointer.
StgStablePtr * entry = stgMallocBytes( sizeof(StgStablePtr)
, "hs_spt_insert: entry"
);
*entry = getStablePtr(spe_closure);
hs_spt_insert_stableptr(key, entry);
}
static void freeSptEntry(void* entry) {
freeStablePtr(*(StgStablePtr*)entry);
stgFree(entry);
}
void hs_spt_remove(StgWord64 key[2]) {
if (spt) {
ACQUIRE_LOCK(&spt_lock);
StgStablePtr* entry = removeHashTable(spt, (StgWord)key, NULL);
RELEASE_LOCK(&spt_lock);
if (entry)
freeSptEntry(entry);
}
}
StgPtr hs_spt_lookup(StgWord64 key1, StgWord64 key2) {
if (spt) {
ACQUIRE_LOCK(&spt_lock);
StgWord64 key[2] = { key1, key2 };
const StgStablePtr * entry = lookupHashTable(spt, (StgWord)key);
const StgPtr ret = entry ? deRefStablePtr(*entry) : NULL;
RELEASE_LOCK(&spt_lock);
return ret;
} else
return NULL;
}
int hs_spt_keys(StgPtr keys[], int szKeys) {
if (spt) {
ACQUIRE_LOCK(&spt_lock);
const int ret = keysHashTable(spt, (StgWord*)keys, szKeys);
RELEASE_LOCK(&spt_lock);
return ret;
} else
return 0;
}
int hs_spt_key_count() {
return spt ? keyCountHashTable(spt) : 0;
}
void exitStaticPtrTable() {
if (spt) {
freeHashTable(spt, freeSptEntry);
spt = NULL;
#if defined(THREADED_RTS)
closeMutex(&spt_lock);
#endif
}
}
|