Ternary operator vs if statement: compiler optimization

Mats Petersson suggestion is generally the best "Write the most readable variant". However, if you are trying to write optimal speed performance code, you need to know more info about your computer and processor. With some machines, the first will run faster (highly pipelined processors: no branching, optimized ternary operator). Other machines will run quicker with the second form (simpler).

Your compiler will optimize it. In the end, there is little to no difference in performance.

There is, however, a big difference in readability. Sometimes the ternary operator can help to remove many lines of code that don't add very much in clarity.

In other cases the if statement is clearer and easier to follow.

Reducing code to a ternary statement but then having to add a ton of comments in order to maintain clarity is counterproductive.

And by all the gods of coding, please don't nest ternary statements.

You could use a branchless ternary operator, sometimes called bitselect ( condition ? true : false).

Don't worry about the extra operations, they are nothing compared to the if statement branching.

bitselect implementation:

inline static int bitselect(int condition, int truereturnvalue, int falsereturnvalue)
{
    return (truereturnvalue & -condition) | (falsereturnvalue & ~(-condition)); //a when TRUE and b when FALSE
}

inline static float bitselect(int condition, float truereturnvalue, float falsereturnvalue)
{
    //Reinterpret floats. Would work because it's just a bit select, no matter the actual value
    int& at = reinterpret_cast<int&>(truereturnvalue);
    int& af = reinterpret_cast<int&>(falsereturnvalue);
    int res = (at & -condition) | (af & ~(-condition)); //a when TRUE and b when FALSE
    return  reinterpret_cast<float&>(res);
}