code: function genStatic (el, state) {
    el.staticProcessed = true;
    // Some elements (templates) need to behave differently inside of a v-pre
    // node.  All pre nodes are static roots, so we can use this as a location to
    // wrap a state change and reset it upon exiting the pre node.
    const originalPreState = state.pre;
    if (el.pre) {
      state.pre = el.pre;
    }
    state.staticRenderFns.push(`with(this){return ${genElement(el, state)}}`);
    state.pre = originalPreState;
    return `_m(${
      state.staticRenderFns.length - 1
    }${
      el.staticInFor ? ',true' : ''
    })`
  }
docs: hoist static sub-trees out