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
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
|
/*
Copyright (c) by respective owners including Yahoo!, Microsoft, and
individual contributors. All rights reserved. Released under a BSD (revised)
license as described in the file LICENSE.
*/
#include "cache.h"
#include "unique_sort.h"
#include "global_data.h"
const size_t neg_1 = 1;
const size_t general = 2;
char* run_len_decode(char *p, uint32_t& i)
{// read an int 7 bits at a time.
size_t count = 0;
while(*p & 128)\
i = i | ((*(p++) & 127) << 7*count++);
i = i | (*(p++) << 7*count);
return p;
}
inline int32_t ZigZagDecode(uint32_t n) { return (n >> 1) ^ -static_cast<int32_t>(n & 1); }
size_t read_cached_tag(io_buf& cache, example* ae)
{
char* c;
size_t tag_size;
if (buf_read(cache, c, sizeof(tag_size)) < sizeof(tag_size))
return 0;
tag_size = *(size_t*)c;
c += sizeof(tag_size);
cache.set(c);
if (buf_read(cache, c, tag_size) < tag_size)
return 0;
ae->tag.erase();
push_many(ae->tag, c, tag_size);
return tag_size+sizeof(tag_size);
}
struct one_float { float f; }
#ifndef _WIN32
__attribute__((packed))
#endif
;
int read_cached_features(void* in, example* ec)
{
vw* all = (vw*)in;
example* ae = (example*)ec;
ae->sorted = all->p->sorted_cache;
io_buf* input = all->p->input;
size_t total = all->p->lp.read_cached_label(all->sd, &ae->l, *input);
if (total == 0)
return 0;
if (read_cached_tag(*input,ae) == 0)
return 0;
char* c;
unsigned char num_indices = 0;
if (buf_read(*input, c, sizeof(num_indices)) < sizeof(num_indices))
return 0;
num_indices = *(unsigned char*)c;
c += sizeof(num_indices);
all->p->input->set(c);
for (;num_indices > 0; num_indices--)
{
size_t temp;
unsigned char index = 0;
if((temp = buf_read(*input,c,sizeof(index) + sizeof(size_t))) < sizeof(index) + sizeof(size_t)) {
cerr << "truncated example! " << temp << " " << char_size + sizeof(size_t) << endl;
return 0;
}
index = *(unsigned char*)c;
c+= sizeof(index);
ae->indices.push_back((size_t)index);
v_array<feature>* ours = ae->atomics+index;
float* our_sum_feat_sq = ae->sum_feat_sq+index;
size_t storage = *(size_t *)c;
c += sizeof(size_t);
all->p->input->set(c);
total += storage;
if (buf_read(*input,c,storage) < storage) {
cerr << "truncated example! wanted: " << storage << " bytes" << endl;
return 0;
}
char *end = c+storage;
uint32_t last = 0;
for (;c!= end;)
{
feature f = {1., 0};
c = run_len_decode(c,f.weight_index);
if (f.weight_index & neg_1)
f.x = -1.;
else if (f.weight_index & general) {
f.x = ((one_float *)c)->f;
c += sizeof(float);
}
*our_sum_feat_sq += f.x*f.x;
uint32_t diff = f.weight_index >> 2;
int32_t s_diff = ZigZagDecode(diff);
if (s_diff < 0)
ae->sorted = false;
f.weight_index = last + s_diff;
last = f.weight_index;
ours->push_back(f);
}
all->p->input->set(c);
}
return (int)total;
}
char* run_len_encode(char *p, size_t i)
{// store an int 7 bits at a time.
while (i >= 128)
{
*(p++) = (i & 127) | 128;
i = i >> 7;
}
*(p++) = (i & 127);
return p;
}
inline uint32_t ZigZagEncode(int32_t n) {
uint32_t ret = (n << 1) ^ (n >> 31);
return ret;
}
void output_byte(io_buf& cache, unsigned char s)
{
char *c;
buf_write(cache, c, 1);
*(c++) = s;
cache.set(c);
}
void output_features(io_buf& cache, unsigned char index, feature* begin, feature* end, uint32_t mask)
{
char* c;
size_t storage = (end-begin) * int_size;
for (feature* i = begin; i != end; i++)
if (i->x != 1. && i->x != -1.)
storage+=sizeof(float);
buf_write(cache, c, sizeof(index) + storage + sizeof(size_t));
*(unsigned char*)c = index;
c += sizeof(index);
char *storage_size_loc = c;
c += sizeof(size_t);
uint32_t last = 0;
for (feature* i = begin; i != end; i++)
{
uint32_t cache_index = (i->weight_index) & mask;
int32_t s_diff = (cache_index - last);
size_t diff = ZigZagEncode(s_diff) << 2;
last = cache_index;
if (i->x == 1.)
c = run_len_encode(c, diff);
else if (i->x == -1.)
c = run_len_encode(c, diff | neg_1);
else {
c = run_len_encode(c, diff | general);
*(float *)c = i->x;
c += sizeof(float);
}
}
cache.set(c);
*(size_t*)storage_size_loc = c - storage_size_loc - sizeof(size_t);
}
void cache_tag(io_buf& cache, v_array<char> tag)
{
char *c;
buf_write(cache, c, sizeof(size_t)+tag.size());
*(size_t*)c = tag.size();
c += sizeof(size_t);
memcpy(c, tag.begin, tag.size());
c += tag.size();
cache.set(c);
}
void cache_features(io_buf& cache, example* ae, uint32_t mask)
{
cache_tag(cache,ae->tag);
output_byte(cache, (unsigned char) ae->indices.size());
for (unsigned char* b = ae->indices.begin; b != ae->indices.end; b++)
output_features(cache, *b, ae->atomics[*b].begin,ae->atomics[*b].end, mask);
}
|
