Move check for foreign objects after the method lookup

* That way, there is a single check for monomorphic call.
  Previously, it would be
    obj = C.new
    c = metaClass(obj)
    if (c != Truffle::Interop::Foreign && c == C) {
      call method
    }

Benchmark:
$ jt -u jvm-ce ruby --trace --fg --igv --engine.Inlining=false --vm.Dgraal.LoopPeeling=false bench_call.rb
class Callee
  def foo
    :foo
  end
end

CALLEE = Callee.new

def compile
  i = 0
  while i < 100
    CALLEE.foo
    i += 1
  end
end

11.times do
  compile
end

Author: eregon

src/main/java/org/truffleruby/language/dispatch/DispatchNode.java

@@ -122,16 +122,15 @@ public Object dispatch(VirtualFrame frame, Object receiver, String methodName, R
     }
 
     public Object execute(VirtualFrame frame, Object receiver, String methodName, RubyProc block, Object[] arguments) {
-
         final RubyClass metaclass = metaclassNode.execute(receiver);
 
-        if (isForeignCall.profile(metaclass == getContext().getCoreLibrary().truffleInteropForeignClass)) {
-            return callForeign(receiver, methodName, block, arguments);
-        }
-
         final InternalMethod method = methodLookup.execute(frame, metaclass, methodName, config);
 
         if (methodMissing.profile(method == null || method.isUndefined())) {
+            if (isForeignCall.profile(metaclass == getContext().getCoreLibrary().truffleInteropForeignClass)) {
+                return callForeign(receiver, methodName, block, arguments);
+            }
+
             switch (config.missingBehavior) {
                 case RETURN_MISSING:
                     return MISSING;