code: @Override
      public void visitCode(Code obj) {
          stack.resetForMethodEntry(this);
          lastOpcode = -1;
          lastReg = -1;
          lastIfEqWasBoolean = false;
          lastLoadWasString = false;
          Arrays.fill(lastPCs, -1);
          branchTargets.clear();
          trimLocations.clear();
          super.visitCode(obj);
      }
docs: implements the visitor to reset the opcode stack
  
  @param obj
  the context object for the currently parsed Code