tailieunhanh - Cracker Handbook 1.0 part 45

Tham khảo tài liệu 'cracker handbook part 45', công nghệ thông tin, kỹ thuật lập trình phục vụ nhu cầu học tập, nghiên cứu và làm việc hiệu quả | It performs a conjunction bit by bit of the operators but differing from AND this instruction does not place the result on the destiny operator it only has effect on the state of the flags. XOR INSTRUCTION Purpose OR exclusive Syntax XOR destiny source Its function is to perform the logic exclusive disjunction of the two operators bit by bit. Source Destiny Destiny 1 1 0 0 0 1 0 1 1 0 0 0 Arithmetic instructions They are used to perform arithmetic operations on the operators. ADC ADD DIV IDIV MUL IMUL SBB SUB ADC INSTRUCTION Purpose Cartage addition Syntax ADC destiny source It carries out the addition of two operators and adds one to the result in case the CF flag is activated this is in case there is carried. The result is stored on the destiny operator. ADD INSTRUCTION Purpose Addition of the operators. Syntax ADD destiny source It adds the two operators and stores the result on the destiny operator. DIV INSTRUCTION Purpose Division without sign. Syntax DIV source The divider can be a byte or a word and it is the operator which is given the instruction. If the divider is 8 bits the 16 bits AX register is taken as dividend and if the divider is 16 bits the even DX AX register will be taken as dividend taking the DX high word and AX as the low. If the divider was a byte then the quotient will be stored on the AL register and the residue on AH if it was a word then the quotient is stored on AX and the residue on DX. IDIV INSTRUCTION Purpose Division with sign. Syntax IDIV source It basically consists on the same as the DIV instruction and the only difference is that this one performs the operation with sign. For its results it used the same registers as the DIV instruction. MUL INSTRUCTION Purpose Multiplication with sign. Syntax MUL source The assembler assumes that the multiplicand will be of the same size as the multiplier therefore it multiplies the value stored on the register .