Question

我有以下几点

我想去看看 AST 使用BinaryOperator visitor。<=BinaryOperator

| |   `-ForStmt 0xfcb1fd8 <line:7:2, line:14:2>
| |     |-DeclStmt 0xfcb1680 <line:7:7, col:20>
| |     | `-VarDecl 0xfcb15e8 <col:7, col:19> col:17 used i 'uint16_t':'unsigned short' cinit
| |     |   `-ImplicitCastExpr 0xfcb1668 <col:19> 'uint16_t':'unsigned short' <IntegralCast>
| |     |     `-IntegerLiteral 0xfcb1648 <col:19> 'int' 0
| |     |-BinaryOperator 0xfcb1a28 <col:22, col:55> 'bool' '<='
| |     | |-ImplicitCastExpr 0xfcb19f8 <col:22> 'int' <IntegralCast>

继承自 我不太明白如何从一个人的身上往下穿越 Expr::BinaryOperator 到 Expr *E:BinaryOperator *BO

static bool vectorLoopConditionVisitor(Sema &S, BinaryOperator *BO){

    if (!BO){
    // error
      }
   if (!BO->isAssignmentOp() && //need a condition to match with "<=" ){  
      // error
    }


  return false;
}

 static bool vectorLoopVisitor(Sema &S, Stmt *St, uint32_t Depth) {
    ForStmt *Fst = dyn_cast<ForStmt>(St);

    // ...
    vectorLoopConditionVisitor(S, dyn_cast<BinaryOperator>(Fst->getCond())); 
    // this is most certainly wrong as it returns a null pointer and segfault
    //...
    vectorLoopBodyVisitor(S, Fst->getBody(), Depth);

    return false;
  }