ast: Address comments
ast: Address comments

ueizhou/tidb,XuHuaiyu/tidb,spongedu/tidb,CodeRushing/tidb,zimulala/tidb,tiancaiamao/tidb,silenceper/tidb,simon-xia/tidb,kyle-wang/tidb,kyle-wang/tidb,kyle-wang/tidb,qiuyesuifeng/tidb,mccxj/tidb,pingcap/tidb,c4pt0r/tidb,yuanwhy/tidb,myrice/tidb,Cofyc/tidb,pingcap/tidb,EvilMcJerkface/tidb,wusphinx/tidb,ming-relax/tidb,ngaut/tidb,anywhy/tidb,liyu4/tidb,ngaut/tidb,ngaut/tidb,ngaut/tidb,pingcap/tidb,ming-relax/tidb,anywhy/tidb,c4pt0r/tidb,qhsong/tidb,mccxj/tidb,gaocegege/tidb,liyu4/tidb,kyle-wang/tidb,EvilMcJerkface/tidb,astaxie/tidb,cosmtrek/tidb,yangwenmai/tidb,8cbx/tidb,louishust/tidb,kyle-wang/tidb,silenceper/tidb,tiancaiamao/tidb,zimulala/tidb,qhsong/tidb,qiuyesuifeng/tidb,ngaut/tidb,c4pt0r/tidb,JinheLin/tidb,yuanwhy/tidb,coocood/tidb,pingcap/tidb,ueizhou/tidb,c4pt0r/tidb,yangwenmai/tidb,Nify/tidb,wusphinx/tidb,astaxie/tidb,spongedu/tidb,Nify/tidb,cosmtrek/tidb,coocood/tidb,pingcap/tidb,CodeRushing/tidb,XuHuaiyu/tidb,louishust/tidb,JinheLin/tidb,c4pt0r/tidb,andelf/tidb,zs634134578/tidb,Cofyc/tidb,silentred/tidb,c4pt0r/tidb,ngaut/tidb,pingcap/tidb,simon-xia/tidb,zs634134578/tidb,andelf/tidb,myrice/tidb,gaocegege/tidb,kyle-wang/tidb,8cbx/tidb,silentred/tidb