<span class="slds-icon_container slds-icon-doctype-xml" title="Description of icon when needed">
      <svg class="slds-icon" aria-hidden="true">
        <use xlink:href="/assets/icons/doctype-sprite/svg/symbols.svg#xml"></use>
      </svg>
      <span class="slds-assistive-text">Description of icon when needed</span>
    </span>