code: private void removeCollectionParameters() {
          int parmCount = SignatureUtils.getNumParameters(getSigConstantOperand());
          if (stack.getStackDepth() >= parmCount) {
              for (int i = 0; i < parmCount; i++) {
                  OpcodeStack.Item item = stack.getStackItem(i);
                  XField field = item.getXField();
                  if (field != null) {
                      collectionFields.remove(field.getName());
                  }
              }
          }
      }
docs: removes collection fields that are passed to other methods as arguments