Loopy CallSite

[Remi Forax]

It seems that the JIT is lost with whe there is a loopy callsite and 
never stabilize (or the steady state is after the program ends).

import java.lang.invoke.MethodHandle;
import java.lang.invoke.MethodHandles;
import java.lang.invoke.MethodType;
import java.lang.invoke.MutableCallSite;

public class Loop {
   static class LoopyCS extends MutableCallSite {
     public LoopyCS() {
       super(MethodType.methodType(void.class, int.class));

       MethodHandle target = dynamicInvoker();
       target = MethodHandles.filterArguments(target, 0, FOO);
       target = MethodHandles.guardWithTest(ZERO,
           target,
MethodHandles.dropArguments(MethodHandles.constant(int.class, 
0).asType(MethodType.methodType(void.class)), 0, int.class));
       setTarget(target);
     }
   }

   static final MethodHandle FOO, ZERO;
   static {
     try {
       FOO = MethodHandles.lookup().findStatic(Loop.class, "foo", 
MethodType.methodType(int.class, int.class));
       ZERO = MethodHandles.lookup().findStatic(Loop.class, "zero", 
MethodType.methodType(boolean.class, int.class));
     } catch (NoSuchMethodException | IllegalAccessException e) {
       throw new AssertionError(e);
     }
   }

   private static boolean zero(int i) {
     return i != 0;
   }

   private static int foo(int i) {
     COUNTER++;
     return i - 1;
   }

   private static int COUNTER = 0;

   public static void main(String[] args) throws Throwable {
     for(int i=0; i<100_000; i++) {
       new LoopyCS().getTarget().invokeExact(1_000);
     }
     System.out.println(COUNTER);
   }
}

cheers,
Rémi