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
|
/*
* 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.
*/
#include "fdr_internal.h"
#include "fdr_compile_internal.h"
#include "fdr_confirm.h"
#include "ue2common.h"
#include "hs_internal.h"
#include "fdr_engine_description.h"
#include "teddy_internal.h"
#include "teddy_engine_description.h"
#include "util/make_unique.h"
#include <cmath>
using namespace std;
namespace ue2 {
TeddyEngineDescription::TeddyEngineDescription(const TeddyEngineDef &def)
: EngineDescription(def.id, targetByArchFeatures(def.cpu_features),
def.numBuckets),
numMasks(def.numMasks), packed(def.packed) {}
u32 TeddyEngineDescription::getDefaultFloodSuffixLength() const {
return numMasks;
}
void getTeddyDescriptions(vector<TeddyEngineDescription> *out) {
static const TeddyEngineDef defns[] = {
{ 3, 0 | HS_CPU_FEATURES_AVX2, 1, 16, false },
{ 4, 0 | HS_CPU_FEATURES_AVX2, 1, 16, true },
{ 5, 0 | HS_CPU_FEATURES_AVX2, 2, 16, false },
{ 6, 0 | HS_CPU_FEATURES_AVX2, 2, 16, true },
{ 7, 0 | HS_CPU_FEATURES_AVX2, 3, 16, false },
{ 8, 0 | HS_CPU_FEATURES_AVX2, 3, 16, true },
{ 9, 0 | HS_CPU_FEATURES_AVX2, 4, 16, false },
{ 10, 0 | HS_CPU_FEATURES_AVX2, 4, 16, true },
{ 11, 0, 1, 8, false },
{ 12, 0, 1, 8, true },
{ 13, 0, 2, 8, false },
{ 14, 0, 2, 8, true },
{ 15, 0, 3, 8, false },
{ 16, 0, 3, 8, true },
{ 17, 0, 4, 8, false },
{ 18, 0, 4, 8, true },
};
out->clear();
for (const auto &def : defns) {
out->emplace_back(def);
}
}
static
size_t maxFloodTailLen(const vector<hwlmLiteral> &vl) {
size_t max_flood_tail = 0;
for (const auto &lit : vl) {
const string &s = lit.s;
assert(!s.empty());
size_t j;
for (j = 1; j < s.length(); j++) {
if (s[s.length() - j - 1] != s[s.length() - 1]) {
break;
}
}
max_flood_tail = max(max_flood_tail, j);
}
return max_flood_tail;
}
/**
* \brief True if this Teddy engine is qualified to handle this set of literals
* on this target.
*/
static
bool isAllowed(const vector<hwlmLiteral> &vl, const TeddyEngineDescription &eng,
const size_t max_lit_len, const target_t &target) {
if (!eng.isValidOnTarget(target)) {
DEBUG_PRINTF("%u disallowed: not valid on target\n", eng.getID());
return false;
}
if (eng.getNumBuckets() < vl.size() && !eng.packed) {
DEBUG_PRINTF("%u disallowed: num buckets < num lits and not packed\n",
eng.getID());
return false;
}
if (eng.getNumBuckets() * TEDDY_BUCKET_LOAD < vl.size()) {
DEBUG_PRINTF("%u disallowed: too many lits for num buckets\n",
eng.getID());
return false;
}
if (eng.numMasks > max_lit_len) {
DEBUG_PRINTF("%u disallowed: more masks than max lit len (%zu)\n",
eng.getID(), max_lit_len);
return false;
}
if (vl.size() > 40) {
u32 n_small_lits = 0;
for (const auto &lit : vl) {
if (lit.s.length() < eng.numMasks) {
n_small_lits++;
}
}
if (n_small_lits * 5 > vl.size()) {
DEBUG_PRINTF("too many short literals (%u)\n", n_small_lits);
return false;
}
}
return true;
}
unique_ptr<TeddyEngineDescription>
chooseTeddyEngine(const target_t &target, const vector<hwlmLiteral> &vl) {
vector<TeddyEngineDescription> descs;
getTeddyDescriptions(&descs);
const TeddyEngineDescription *best = nullptr;
const size_t max_lit_len = maxLen(vl);
const size_t max_flood_tail = maxFloodTailLen(vl);
DEBUG_PRINTF("%zu lits, max_lit_len=%zu, max_flood_tail=%zu\n", vl.size(),
max_lit_len, max_flood_tail);
u32 best_score = 0;
for (size_t engineID = 0; engineID < descs.size(); engineID++) {
const TeddyEngineDescription &eng = descs[engineID];
if (!isAllowed(vl, eng, max_lit_len, target)) {
continue;
}
u32 score = 0;
// We prefer unpacked Teddy models.
if (!eng.packed) {
score += 100;
}
// If we're heavily loaded, we prefer to have more masks.
if (vl.size() > 4 * eng.getNumBuckets()) {
score += eng.numMasks * 4;
} else {
// Lightly loaded cases are great.
score += 100;
}
// We want enough masks to avoid becoming flood-prone.
if (eng.numMasks > max_flood_tail) {
score += 50;
}
// We prefer having 3 masks. 3 is just right.
score += 6 / (abs(3 - (int)eng.numMasks) + 1);
// We prefer cheaper, smaller Teddy models.
score += 16 / eng.getNumBuckets();
DEBUG_PRINTF("teddy %u: masks=%u, buckets=%u, packed=%u "
"-> score=%u\n",
eng.getID(), eng.numMasks, eng.getNumBuckets(),
eng.packed ? 1U : 0U, score);
if (!best || score > best_score) {
best = ŋ
best_score = score;
}
}
if (!best) {
DEBUG_PRINTF("failed to find engine\n");
return nullptr;
}
DEBUG_PRINTF("using engine %u\n", best->getID());
return ue2::make_unique<TeddyEngineDescription>(*best);
}
unique_ptr<TeddyEngineDescription> getTeddyDescription(u32 engineID) {
vector<TeddyEngineDescription> descs;
getTeddyDescriptions(&descs);
for (const auto &desc : descs) {
if (desc.getID() == engineID) {
return ue2::make_unique<TeddyEngineDescription>(desc);
}
}
return nullptr;
}
} // namespace ue2
|
