Re: To go with Go or C/C++?

On Tue, 7 May 2013 22:41:49 +0200
Melzzzzz <mel@zzzzz.com> wrote:


With more realistic example:

bmaxa@maxa:~/examples$ cat module.cpp
#include <cstring>
#include <stdexcept>

bool checkThingsWithIf( int param, char* error, unsigned errsz )throw()
{
        if( param % 10000 == 0)
        {
                strncpy(error,"some error",errsz);
                return false;
        }
        return true;
}

void checkThingsWithTry( int param )
{
        if ( param % 10000 == 0 )
        {
                throw std::runtime_error("some error");
        }
}

bmaxa@maxa:~/examples$ cat tryif.cpp
#include <cstdio>
#include <ctime>
#include <exception>

int ms_elapsed( clock_t start, clock_t stop )
{
        return static_cast<int>( 1000.0 * ( stop - start ) / CLOCKS_PER_SEC=
 );
}

bool checkThingsWithIf( int param, char* error,unsigned errsz )throw();

void checkThingsWithTry( int param );

int testWithIf( int param )
{
        int ret;
        char buf[256];
        for ( int j = 0; j < 200; ++j )
        {
                if ( !checkThingsWithIf( param+j,buf,sizeof buf ) )
                {
                        return ret;
                }
                ++ret;
        }
        return ret;
}

int testWithTry( int param )
{
        int ret;
        try
        {
                for ( int j = 0; j < 200; ++j )
                {
                        checkThingsWithTry( param+j );
                        ++ret;
                }
        }
        catch (const std::exception& )
        { }
        return ret;
}

void benchmark( int (*foo)(int), const char* label)
{
        clock_t volatile start;
        clock_t volatile stop;
        int volatile sum;

        start = clock();
        sum = 0;
        for ( int i = 0; i < 1000000; ++i )
        {
                sum += (*foo)( i );
        }
        stop = clock();
        printf( "%s it took %d msec; (sum %d)\n", label,ms_elapsed( start,s=
top) , sum );
}

int main( int argc, char* argv[] )
{
        benchmark( &testWithTry,"With try");
        benchmark( &testWithIf,"With if");
}

bmaxa@maxa:~/examples$ g++-trunk -c -O2 module.cpp -o module.o
bmaxa@maxa:~/examples$ g++-trunk -O2 tryif.cpp module.o -o tryif
bmaxa@maxa:~/examples$ ./tryif
With try it took 340 msec; (sum 197990000)
With if it took 410 msec; (sum 197990000)
bmaxa@maxa:~/examples$ g++-trunk -c -O1 module.cpp -o module.o
bmaxa@maxa:~/examples$ g++-trunk -O1 tryif.cpp module.o -o tryif
bmaxa@maxa:~/examples$ ./tryif
With try it took 490 msec; (sum 197990000)
With if it took 510 msec; (sum 197990000)
bmaxa@maxa:~/examples$ g++-trunk -c -O0 module.cpp -o module.o
bmaxa@maxa:~/examples$ g++-trunk -O0 tryif.cpp module.o -o tryif
bmaxa@maxa:~/examples$ ./tryif
With try it took 870 msec; (sum 1525529904)
With if it took 860 msec; (sum 1525529904)

Seems that exceptions win when throwing exception
objects instead of filling error buffer;)