Optimize Interpreter -> Native / Compiled calls.

[mbebenita]

Calling natives or compiled methods from the interpreter requires popping arguments off the stack, putting them in an array and then using apply. This is pretty slow and we should optimize calls for the most frequent cases. Below are the frequencies of the most common signature kinds during the startup of my favorite midlet. At the very least, we ought to special case the no argument case, which appears to be the most frequent.

Freq Signature Kinds: [Return Kind, Argument 0 Kind, Argument 1 Kind, ...]
  62 0 
   3 0,0,4,8,4,4 
 382 0,3 
   8 0,4 
   2 0,4,8 
 757 0,8 
  35 0,8,4 
   1 0,8,4,4,8,8,8,8,8,4,4,4,8,0 
  26 0,8,8 
   8 1 
   5 3 
 752 3,3 
 225 3,4 
2200 4 
  12 4,3,4 
  57 4,4 
 103 4,4,4 
   3 4,5 
   1 4,6 
 186 4,8 
 143 4,8,4 
  44 4,8,4,4 
  10 4,8,8 
   4 4,8,8,4,4 
  35 6 
   2 6,6 
   1 6,6,6 
   3 6,7 
   4 6,8,8 
2436 8 
  14 8,3 
   6 8,3,3 
 163 8,4 
   2 8,4,0 
 102 8,4,4 
   2 8,4,4,4 
   8 8,4,8 
  10 8,6 
   4 8,6,4 
 511 8,8 
   1 8,8  
   3 8,8,3 
   7 8,8,4 
  20 8,8,4,0 
   3 8,8,4,0,0 
   3 8,8,4,4 
   6 8,8,4,4,4,4,8 
   1 8,8,4,4,8,8,8,8,8,4,4,4,8,0 
 134 8,8,8 
   3 8,8,8,0 
3394 9 
  16 9,0 
   2 9,1 
 682 9,4 
   4 9,4,0 
  17 9,4,3 
  72 9,4,4 
   1 9,4,4,4 
  86 9,4,4,8 
 238 9,4,4,8,4 
 123 9,4,8 
   2 9,4,8,0 
   2 9,4,8,4,4,8 
   2 9,4,8,4,8 
  16 9,6 
   8 9,6,8 
   3 9,6,8,0 
   5 9,6,8,6 
 807 9,8 
   2 9,8,0 
  26 9,8,4 
  99 9,8,4,4 
   6 9,8,4,4,4,4,8 
   2 9,8,4,4,4,8,8,4 
   2 9,8,4,4,8 
   3 9,8,4,8 
 384 9,8,4,8,4,4 
   1 9,8,6 
 118 9,8,8 
   4 9,8,8,4 
   7 9,8,8,4,4 
   4 9,8,8,4,8 
  25 9,8,8,8 
   4 9,8,8,8,8 
   6 9,8,8,8,8,8

[marco-c]

Aren't we already doing this?

            var argumentSlots = calleeMethodInfo.hasTwoSlotArguments ? -1 : calleeMethodInfo.argumentSlots;
            switch (argumentSlots) {
              case 0:
                returnValue = calleeMethod.call(object);
                break;
              case 1:
                a = stack.pop();
                returnValue = calleeMethod.call(object, a);
                break;
              case 2:
                b = stack.pop();
                a = stack.pop();
                returnValue = calleeMethod.call(object, a, b);
                break;
              case 3:
                c = stack.pop();
                b = stack.pop();
                a = stack.pop();
                returnValue = calleeMethod.call(object, a, b, c);
                break;
              default:
                if (calleeMethodInfo.hasTwoSlotArguments) {
                  frame.popArgumentsInto(calleeMethodInfo, argArray);
                } else {
                  popManyInto(stack, calleeMethodInfo.argumentSlots, argArray);
                }
                var returnValue = calleeMethod.apply(object, argArray);
            }

[mbebenita]

Yes. I should have prefixed the issue with, "we need to do this for the new interpreter."

[marco-c]

#1605 adds the no-argument fast path.