Here is a simple bit of C that sets either x or y to value v depending on the value of c..

if (c)   
    x = v;  
else  
    y = v;

..but why not "improve" this by using the C ternary operator ? : as follows:

 *(c ? &x : &y) = v;

Now, how does this shape up when compiled on an x86 with gcc -O2 ?  Well, the first example compiles down to a test and a branch where as the second example uses a conditional move instruction (cmove) and avoids the test and branch and is faster code.  Result!

OK, so this isn't rocket science, but does show that a little bit of abuse of the ternary operator can save me a few cycles if the compiler is clued up to use cmove.

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