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
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
|
/*
* Copyright (c) 2015-2017, Intel Corporation
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are met:
*
* * Redistributions of source code must retain the above copyright notice,
* this list of conditions and the following disclaimer.
* * Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* * Neither the name of Intel Corporation nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
* AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
* LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
* CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
* SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
* CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGE.
*/
/** \file
* \brief Shufti acceleration: compile code.
*/
#include "shufticompile.h"
#include "ue2common.h"
#include "util/charreach.h"
#include "util/container.h"
#include "util/flat_containers.h"
#include <array>
#include <cassert>
#include <cstring>
#include <map>
using namespace std;
namespace ue2 {
/** \brief Single-byte variant.
*
* Returns -1 if unable to construct masks, otherwise returns number of bits
* used in the mask.
*
* Note: always able to construct masks for 8 or fewer characters.
*/
int shuftiBuildMasks(const CharReach &c, u8 *lo, u8 *hi) {
/* Things could be packed much more optimally, but this should be able to
* handle any set of characters entirely in the lower half. */
assert(c.count() < 256);
assert(!c.none());
map<u8, CharReach> by_hi; /* hi nibble -> set of matching lo nibbles */
/* group matching characters by high nibble */
for (size_t i = c.find_first(); i != CharReach::npos; i = c.find_next(i)) {
u8 it_hi = i >> 4;
u8 it_lo = i & 0xf;
by_hi[it_hi].set(it_lo);
}
map<CharReach, CharReach> by_lo_set;
/* group all hi nibbles with a common set of lo nibbles together */
for (map<u8, CharReach>::const_iterator it = by_hi.begin();
it != by_hi.end(); ++it) {
by_lo_set[it->second].set(it->first);
}
if (by_lo_set.size() > 8) {
/* too many char classes on the dance floor */
assert(c.size() > 8);
return -1;
}
u8 bit_index = 0;
array<u8, 16> lo_a; lo_a.fill(0);
array<u8, 16> hi_a; hi_a.fill(0);
for (map<CharReach, CharReach>::const_iterator it = by_lo_set.begin();
it != by_lo_set.end(); ++it) {
const CharReach &lo_nibbles = it->first;
const CharReach &hi_nibbles = it->second;
/* set bits in low mask */
for (size_t j = lo_nibbles.find_first(); j != CharReach::npos;
j = lo_nibbles.find_next(j)) {
lo_a[j] |= (1 << bit_index);
}
/* set bits in high mask */
for (size_t j = hi_nibbles.find_first(); j != CharReach::npos;
j = hi_nibbles.find_next(j)) {
hi_a[j] |= (1 << bit_index);
}
bit_index++;
}
memcpy(lo, lo_a.data(), sizeof(m128));
memcpy(hi, hi_a.data(), sizeof(m128));
return bit_index;
}
static
array<u16, 4> or_array(array<u16, 4> a, const array<u16, 4> &b) {
a[0] |= b[0];
a[1] |= b[1];
a[2] |= b[2];
a[3] |= b[3];
return a;
}
#define MAX_BUCKETS 8
static
void set_buckets_from_mask(u16 nibble_mask, u32 bucket,
array<u8, 16> &byte_mask) {
assert(bucket < MAX_BUCKETS);
u32 mask = nibble_mask;
while (mask) {
u32 n = findAndClearLSB_32(&mask);
byte_mask[n] &= ~(1 << bucket);
}
}
bool shuftiBuildDoubleMasks(const CharReach &onechar,
const flat_set<pair<u8, u8>> &twochar,
u8 *lo1, u8 *hi1, u8 *lo2, u8 *hi2) {
DEBUG_PRINTF("unibytes %zu dibytes %zu\n", onechar.size(),
twochar.size());
array<u8, 16> lo1_a;
array<u8, 16> lo2_a;
array<u8, 16> hi1_a;
array<u8, 16> hi2_a;
lo1_a.fill(0xff);
lo2_a.fill(0xff);
hi1_a.fill(0xff);
hi2_a.fill(0xff);
// two-byte literals
vector<array<u16, 4>> nibble_masks;
for (const auto &p : twochar) {
DEBUG_PRINTF("%02hhx %02hhx\n", p.first, p.second);
u16 a_lo = 1U << (p.first & 0xf);
u16 a_hi = 1U << (p.first >> 4);
u16 b_lo = 1U << (p.second & 0xf);
u16 b_hi = 1U << (p.second >> 4);
nibble_masks.push_back({{a_lo, a_hi, b_lo, b_hi}});
}
// one-byte literals (second byte is a wildcard)
for (size_t it = onechar.find_first(); it != CharReach::npos;
it = onechar.find_next(it)) {
DEBUG_PRINTF("%02hhx\n", (u8)it);
u16 a_lo = 1U << (it & 0xf);
u16 a_hi = 1U << (it >> 4);
u16 wildcard = 0xffff;
nibble_masks.push_back({{a_lo, a_hi, wildcard, wildcard}});
}
// try to merge strings into shared buckets
for (u32 i = 0; i < 4; i++) {
map<array<u16, 4>, array<u16, 4>> new_masks;
for (const auto &a : nibble_masks) {
auto key = a;
key[i] = 0;
if (!contains(new_masks, key)) {
new_masks[key] = a;
} else {
new_masks[key] = or_array(new_masks[key], a);
}
}
nibble_masks.clear();
for (const auto &e : new_masks) {
nibble_masks.push_back(e.second);
}
}
if (nibble_masks.size() > MAX_BUCKETS) {
DEBUG_PRINTF("too many buckets needed (%zu)\n", nibble_masks.size());
return false;
}
u32 i = 0;
for (const auto &a : nibble_masks) {
set_buckets_from_mask(a[0], i, lo1_a);
set_buckets_from_mask(a[1], i, hi1_a);
set_buckets_from_mask(a[2], i, lo2_a);
set_buckets_from_mask(a[3], i, hi2_a);
i++;
}
memcpy(lo1, lo1_a.data(), sizeof(m128));
memcpy(lo2, lo2_a.data(), sizeof(m128));
memcpy(hi1, hi1_a.data(), sizeof(m128));
memcpy(hi2, hi2_a.data(), sizeof(m128));
return true;
}
#ifdef DUMP_SUPPORT
CharReach shufti2cr(const u8 *lo, const u8 *hi) {
CharReach cr;
for (u32 i = 0; i < 256; i++) {
if (lo[(u8)i & 0xf] & hi[(u8)i >> 4]) {
cr.set(i);
}
}
return cr;
}
#endif // DUMP_SUPPORT
} // namespace ue2
|
