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// Copyright (c) 2001-2010 Hartmut Kaiser
//
// Distributed under the Boost Software License, Version 1.0. (See accompanying
// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
#include <climits>
#include <cstdlib>
#include <iostream>
#include <sstream>
#include <boost/format.hpp>
#include "../high_resolution_timer.hpp"
// This value specifies, how to unroll the integer string generation loop in
// Karma.
// Set this to some integer in between 0 (no unrolling) and max expected
// integer string len (complete unrolling). If not specified, this value
// defaults to 6.
#define BOOST_KARMA_NUMERICS_LOOP_UNROLL 6
#include <boost/spirit/include/karma.hpp>
using namespace std;
using namespace boost::spirit;
#define MAX_ITERATION 10000000
///////////////////////////////////////////////////////////////////////////////
struct random_fill
{
int operator()() const
{
int scale = std::rand() / 100 + 1;
return (std::rand() * std::rand()) / scale;
}
};
///////////////////////////////////////////////////////////////////////////////
int main()
{
namespace karma = boost::spirit::karma;
cout << "Converting " << MAX_ITERATION
<< " randomly generated int values to strings." << flush << endl;
std::srand(0);
std::vector<int> v (MAX_ITERATION);
std::generate(v.begin(), v.end(), random_fill()); // randomly fill the vector
// test the C libraries ltoa function (the most low level function for
// string conversion available)
{
//[karma_int_performance_ltoa
char buffer[65]; // we don't expect more than 64 bytes to be generated here
//<-
std::string str;
util::high_resolution_timer t;
//->
for (int i = 0; i < MAX_ITERATION; ++i)
{
ltoa(v[i], buffer, 10);
//<-
str = buffer; // compensate for string ops in other benchmarks
//->
}
//]
cout << "ltoa:\t\t" << t.elapsed() << " [s]" << flush << endl;
}
// test the iostreams library
{
//[karma_int_performance_iostreams
std::stringstream str;
//<-
util::high_resolution_timer t;
//->
for (int i = 0; i < MAX_ITERATION; ++i)
{
str.str("");
str << v[i];
}
//]
cout << "iostreams:\t" << t.elapsed() << " [s]" << flush << endl;
}
// test the Boost.Format library
{
//[karma_int_performance_format
std::string str;
boost::format int_format("%d");
//<-
util::high_resolution_timer t;
//->
for (int i = 0; i < MAX_ITERATION; ++i)
{
str = boost::str(int_format % v[i]);
}
//]
cout << "Boost.Format:\t" << t.elapsed() << " [s]" << flush << endl;
}
// test the Karma int_ generation routines
{
std::string str;
util::high_resolution_timer t;
//[karma_int_performance_plain
char buffer[65]; // we don't expect more than 64 bytes to be generated here
for (int i = 0; i < MAX_ITERATION; ++i)
{
char *ptr = buffer;
karma::generate(ptr, int_, v[i]);
*ptr = '\0';
//<-
str = buffer; // compensate for string ops in other benchmarks
//->
}
//]
cout << "int_:\t\t" << t.elapsed() << " [s]" << flush << endl;
}
return 0;
}
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