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
|
/*
Copyright 2005-2015 Intel Corporation. All Rights Reserved.
This file is part of Threading Building Blocks. Threading Building Blocks is free software;
you can redistribute it and/or modify it under the terms of the GNU General Public License
version 2 as published by the Free Software Foundation. Threading Building Blocks is
distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the
implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
See the GNU General Public License for more details. You should have received a copy of
the GNU General Public License along with Threading Building Blocks; if not, write to the
Free Software Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
As a special exception, you may use this file as part of a free software library without
restriction. Specifically, if other files instantiate templates or use macros or inline
functions from this file, or you compile this file and link it with other files to produce
an executable, this file does not by itself cause the resulting executable to be covered
by the GNU General Public License. This exception does not however invalidate any other
reasons why the executable file might be covered by the GNU General Public License.
*/
#if __TBB_MIC_OFFLOAD
#pragma offload_attribute (push,target(mic))
#endif // __TBB_MIC_OFFLOAD
#include <iostream>
#include <string>
#include <algorithm>
#include "tbb/parallel_for.h"
#include "tbb/blocked_range.h"
#include "tbb/tick_count.h"
#if __TBB_MIC_OFFLOAD
#pragma offload_attribute (pop)
class __declspec(target(mic)) SubStringFinder;
#endif // __TBB_MIC_OFFLOAD
using namespace tbb;
using namespace std;
static const size_t N = 22;
void SerialSubStringFinder ( const string &str, size_t *max_array, size_t *pos_array) {
for ( size_t i = 0; i < str.size(); ++i ) {
size_t max_size = 0, max_pos = 0;
for (size_t j = 0; j < str.size(); ++j)
if (j != i) {
size_t limit = str.size()-( i > j ? i : j );
for (size_t k = 0; k < limit; ++k) {
if (str[i + k] != str[j + k]) break;
if (k > max_size) {
max_size = k;
max_pos = j;
}
}
}
max_array[i] = max_size;
pos_array[i] = max_pos;
}
}
class SubStringFinder {
const string str;
size_t *max_array;
size_t *pos_array;
public:
void operator() ( const blocked_range<size_t>& r ) const {
for ( size_t i = r.begin(); i != r.end(); ++i ) {
size_t max_size = 0, max_pos = 0;
for (size_t j = 0; j < str.size(); ++j)
if (j != i) {
size_t limit = str.size()-( i > j ? i : j );
for (size_t k = 0; k < limit; ++k) {
if (str[i + k] != str[j + k]) break;
if (k > max_size) {
max_size = k;
max_pos = j;
}
}
}
max_array[i] = max_size;
pos_array[i] = max_pos;
}
}
SubStringFinder(string &s, size_t *m, size_t *p) :
str(s), max_array(m), pos_array(p) { }
};
int main(int argc, char *argv[]) {
string str[N] = { string("a"), string("b") };
for (size_t i = 2; i < N; ++i) str[i] = str[i-1]+str[i-2];
string &to_scan = str[N-1];
size_t num_elem = to_scan.size();
size_t *max = new size_t[num_elem];
size_t *max2 = new size_t[num_elem];
size_t *pos = new size_t[num_elem];
size_t *pos2 = new size_t[num_elem];
cout << " Done building string." << endl;
tick_count serial_t0 = tick_count::now();
SerialSubStringFinder(to_scan, max2, pos2);
tick_count serial_t1 = tick_count::now();
cout << " Done with serial version." << endl;
tick_count parallel_t0 = tick_count::now();
parallel_for(blocked_range<size_t>(0, num_elem, 100),
SubStringFinder( to_scan, max, pos ) );
tick_count parallel_t1 = tick_count::now();
cout << " Done with parallel version." << endl;
for (size_t i = 0; i < num_elem; ++i) {
if (max[i] != max2[i] || pos[i] != pos2[i]) {
cout << "ERROR: Serial and Parallel Results are Different!" << endl;
}
}
cout << " Done validating results." << endl;
cout << "Serial version ran in " << (serial_t1 - serial_t0).seconds() << " seconds" << endl
<< "Parallel version ran in " << (parallel_t1 - parallel_t0).seconds() << " seconds" << endl
<< "Resulting in a speedup of " << (serial_t1 - serial_t0).seconds() / (parallel_t1 - parallel_t0).seconds() << endl;
#if __TBB_MIC_OFFLOAD
// Do offloadable version. Do the timing on host.
size_t *max3 = new size_t[num_elem];
size_t *pos3 = new size_t[num_elem];
tick_count parallel_tt0 = tick_count::now();
const char* to_scan_str = to_scan.c_str(); // Offload the string as a char array.
#pragma offload target(mic) in(num_elem) in(to_scan_str:length(num_elem)) out(max3,pos3:length(num_elem))
{
string to_scan(to_scan_str, num_elem); // Reconstruct the string in offloadable region.
// Suboptimal performance because of making a copy from to_scan_str at creating to_scan.
parallel_for(blocked_range<size_t>(0, num_elem, 100),
SubStringFinder( to_scan, max3, pos3 ) );
}
tick_count parallel_tt1 = tick_count::now();
cout << " Done with offloadable version." << endl;
// Do validation of offloadable results on host.
for (size_t i = 0; i < num_elem; ++i) {
if (max3[i] != max2[i] || pos3[i] != pos2[i]) {
cout << "ERROR: Serial and Offloadable Results are Different!" << endl;
}
}
cout << " Done validating offloadable results." << endl;
cout << "Offloadable version ran in " << (parallel_tt1 - parallel_tt0).seconds() << " seconds" << endl
<< "Resulting in a speedup of " << (serial_t1 - serial_t0).seconds() / (parallel_tt1 - parallel_tt0).seconds() << " of offloadable version" << endl;
delete[] max3;
delete[] pos3;
#endif // __TBB_MIC_OFFLOAD
delete[] max;
delete[] pos;
delete[] max2;
delete[] pos2;
return 0;
}
|
