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javarecursiontail-call-optimizationtail-call

Tail recursion optimization and recursion in Java

I have a question about tail calls optimization, I need to know how this java code behaves:

private void doSomething(int v) {

    inf f = someCalculation(v);

    if (f < 0) doSomething(v/2);
    else doSomething(v*2);

}

This code is a nonsense example but my question is, in such a case:

  1. The first doSomething() call would be optimized?
  2. The second doSomething() call would be optimized?
  3. The if/else block affects in any way the optimization?

Thanks

EDIT:

Please provide an example on how you would do this if the language was not Java but something else that has TCO

Solution

  • Java 8 has no Tail Call Optimization whatsoever. No calls will be optimized (turned into iteration/goto statements).

    The discussion over TCO for Java has a long history, though, with Guy Steele being one of its best-known proponents.

    I recommend reading this post from the mlvm-dev mailing list for a recent review of the subject.