mysql5/mysql-5.7.27/unittest/gunit/strings_strnxfrm-t.cc

148 lines
4.4 KiB
C++

/* Copyright (c) 2014, Oracle and/or its affiliates. All rights reserved.
This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; version 2 of the License.
This program 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 this program; if not, write to the Free Software
Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA */
/*
Bug#16403708 SUBOPTIMAL CODE IN MY_STRNXFRM_SIMPLE()
Bug#68476 Suboptimal code in my_strnxfrm_simple()
Below we test some alternative implementations for my_strnxfrm_simple.
In order to do benchmarking, configure in optimized mode, and
generate a separate executable for this file:
cmake -DMERGE_UNITTESTS=0
You may want to tweak some constants below:
- experiment with num_iterations
run './strings_strnxfrm-t --disable-tap-output'
to see timing reports for your platform.
Benchmarking with gcc and clang indicates that:
There is insignificant difference between my_strnxfrm_simple and strnxfrm_new
when src != dst
my_strnxfrm_simple() is significantly faster than strnxfrm_new
when src == dst, especially for long strings.
Loop unrolling gives significant speedup for large strings.
*/
// First include (the generated) my_config.h, to get correct platform defines.
#include "my_config.h"
#include <gtest/gtest.h>
#include <vector>
#include "strnxfrm.h"
namespace strnxfrm_unittest {
#if defined(GTEST_HAS_PARAM_TEST)
#if !defined(DBUG_OFF)
// There is no point in benchmarking anything in debug mode.
const size_t num_iterations= 1ULL;
#else
// Set this so that each test case takes a few seconds.
// And set it back to a small value before pushing!!
// const size_t num_iterations= 20000000ULL;
const size_t num_iterations= 2ULL;
#endif
class StrnxfrmTest : public ::testing::TestWithParam<size_t>
{
protected:
virtual void SetUp()
{
m_length= GetParam();
m_src.assign(m_length, 0x20);
m_dst.assign(m_length, 0x20);
}
std::vector<uchar> m_src;
std::vector<uchar> m_dst;
size_t m_length;
};
size_t test_values[]= {1, 10, 100, 1000};
INSTANTIATE_TEST_CASE_P(Strnxfrm, StrnxfrmTest,
::testing::ValuesIn(test_values));
TEST_P(StrnxfrmTest, OriginalSrcDst)
{
for (size_t ix= 0; ix < num_iterations; ++ix)
strnxfrm_orig(&my_charset_latin1,
&m_dst[0], m_length, m_length,
&m_src[0], m_length, 192);
}
TEST_P(StrnxfrmTest, OriginalUnrolledSrcDst)
{
for (size_t ix= 0; ix < num_iterations; ++ix)
strnxfrm_orig_unrolled(&my_charset_latin1,
&m_dst[0], m_length, m_length,
&m_src[0], m_length, 192);
}
TEST_P(StrnxfrmTest, ModifiedSrcDst)
{
for (size_t ix= 0; ix < num_iterations; ++ix)
strnxfrm_new(&my_charset_latin1,
&m_dst[0], m_length, m_length,
&m_src[0], m_length, 192);
}
TEST_P(StrnxfrmTest, ModifiedUnrolledSrcDst)
{
for (size_t ix= 0; ix < num_iterations; ++ix)
strnxfrm_new_unrolled(&my_charset_latin1,
&m_dst[0], m_length, m_length,
&m_src[0], m_length, 192);
}
TEST_P(StrnxfrmTest, OriginalSrcSrc)
{
for (size_t ix= 0; ix < num_iterations; ++ix)
strnxfrm_orig(&my_charset_latin1,
&m_src[0], m_length, m_length,
&m_src[0], m_length, 192);
}
TEST_P(StrnxfrmTest, OriginalUnrolledSrcSrc)
{
for (size_t ix= 0; ix < num_iterations; ++ix)
strnxfrm_orig_unrolled(&my_charset_latin1,
&m_src[0], m_length, m_length,
&m_src[0], m_length, 192);
}
TEST_P(StrnxfrmTest, ModifiedSrcSrc)
{
for (size_t ix= 0; ix < num_iterations; ++ix)
strnxfrm_new(&my_charset_latin1,
&m_src[0], m_length, m_length,
&m_src[0], m_length, 192);
}
TEST_P(StrnxfrmTest, ModifiedUnrolledSrcSrc)
{
for (size_t ix= 0; ix < num_iterations; ++ix)
strnxfrm_new_unrolled(&my_charset_latin1,
&m_src[0], m_length, m_length,
&m_src[0], m_length, 192);
}
#endif // GTEST_HAS_PARAM_TEST
}