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
|
# File 'ext/sumbur/sumbur.c', line 20
static VALUE
rb_sumbur(VALUE self, VALUE hashed_int, VALUE capacity)
{
unsigned int h = NUM2UINT(hashed_int);
unsigned int capa = NUM2UINT(capacity);
unsigned int part, n, i, c;
if (capa == 0) {
rb_raise(rb_eArgError, "Sumbur is not applicable to empty cluster");
}
part = L / capa;
if (L - h < part) return INT2FIX(0);
n = 1;
do {
if (h >= L / 2) h -= L / 2;
else {
n = 2;
if (L / 2 - h < part) return INT2FIX(1);
}
if (capa == 2) return INT2FIX(1);
#define curslice(i) (L / (i * (i - 1)))
#define unroll(i) \
if (curslice(i) <= h) h -= curslice(i); \
else { \
h += curslice(i) * (i - n - 1); \
n = i; \
if (L / i - h < part) return INT2FIX(n-1); \
} \
if (capa == i) return INT2FIX(n-1)
unroll(3); unroll(4); unroll(5);
unroll(6); unroll(7); unroll(8);
unroll(9); unroll(10); unroll(11);
unroll(12); unroll(13); unroll(14);
unroll(15); unroll(16); unroll(17);
unroll(18); unroll(19); unroll(20);
unroll(21); unroll(22); unroll(23);
unroll(24); unroll(25); unroll(26);
for (i = 27; i <= capa && i <= 62; i++) {
c = LL27_38[i-27];
if (c <= h) {
h -= c;
}
else {
h += c * (i - n - 1);
n = i;
if (L27_38[i-27] - h < part) return INT2FIX(n-1);
}
}
for(i = 63; i <= capa; i++) {
c = L / (i * (i - 1));
if (c <= h) {
h -= c;
}
else {
h += c * (i - n - 1);
n = i;
if (L / i - h < part) return INT2FIX(n - 1);
}
}
} while(0);
return INT2FIX(n - 1);
}
|