this.operand2 = getOperand(varIndex2); refs = new Operand[]{operand1, operand2};
refs = new Operand[]{ getOperand(varIndex1), getOperand(varIndex2) };
    public ConditionalBranchQuad(int address, IRBasicBlock block,                                 int varIndex1, int condition, int varIndex2, int targetAddress) {        super(address, block, targetAddress);        if (condition < IF_ICMPEQ || condition > IF_ACMPNE) {            throw new IllegalArgumentException("can't use that condition here");        }        this.operand1 = getOperand(varIndex1);        this.condition = condition;        this.commutative = condition == IF_ICMPEQ ||                           condition == IF_ICMPNE ||                           condition == IF_ACMPEQ ||                           condition == IF_ACMPNE;        this.operand2 = getOperand(varIndex2);        refs = new Operand[]{operand1, operand2};    }