LCC编译器的源程序分析(63)创建DAG森林的源程序

#001 //

#002 void walk(Tree tp, int tlab, int flab)

#003 {

#004  //创建DAG森林.

#005  listnodes(tp, tlab, flab);

#006 

#007  //如果DAG森林生成.

#008  if (forest)

#009  {

#010         Node list = forest->link;

#011         forest->link = NULL;

#012 

#013         //把多次引用的DAG节点,修改为对临时变量的引用.

#014         if (!IR->wants_dag && errcnt == 0)

#015         {

#016               list = undag(list);

#017         }   

#018        

#019         //创建代码块保存DAG的列表.

#020         AppendCode(code::Gen)->u.forest = list;

#021         forest = NULL;

#022  }

#023 

#024  reset();

#025  deallocate(STMT);

#026 }