Is performance really striking when catching exceptions?

Question

I asked a question about exceptions , and I get really annoyed when people say that the throw is slow. I asked in the past How exceptions work behind the scenes , and I know that there are additional instructions in the regular code (as the accepted answer says), but I am not completely convinced that the throw is more expensive than checking the return values. Consider the following:

{
    int ret = func();
    if (ret == 1)
        return;
    if (ret == 2)
        return;
    doSomething();
}

vs

{
    try{
        func();
        doSomething();
    }
    catch (SpecificException1 e)
    {
    }
    catch (SpecificException2 e)
    {
    }
}

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Answer 1

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:

#include <stdio.h>
#include <intrin.h>

int Test1()
{
    throw 1;
//  return 1;
}


int main(int argc, char*argv[])
{
    int result = 0;
    __int64 time = 0xFFFFFFFF;
    for(int i=0; i<10000; i++)
    {
        __int64 start = __rdtsc();
        try
        {
            result += Test1();
        }
        catch(int x)
        {
            result += x;
        }
        __int64 end = __rdtsc();
        if(time > end - start)
            time = end - start;
    }

    printf("%d\n", result);
    printf("time: %I64d\n", time);
}

try/catch, op

try
{
        if(Test1()!=0)
                result++;
}
catch(int x)
{
        result++;

Answer 2

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Answer 3

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Answer 6

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• http://en.wikipedia.org/wiki/Program_optimization
• http://www.flounder.com/optimization.htm

Answer 7

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Answer 8

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Answer 9

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Answer 10

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