Question

After the following MASM code is executed:

  MOV   EAX, 212
  MOV   EBX, 19
  CDQ
  DIV   EBX

What is the value in the EAX register (in decimal)?
What is the value in the EBX register (in decimal)?
What is the value in the EDX register (in decimal)?

Answer 1

Please up vote ,comment if any query .

Answer :

EAX =11

EBX = 19

EDX = 3

Explanation :

MOV EAX ,212 ; this instruction copy value 212 immediate value into EAX register EAX = 212

MOV EBX ,19 ; This instruction copy immediate value 19 into EBX register EBX = 19

CDQ ; this instruction convert 32 bit EAX to 64 bit EDX : EAX by copying sign bit (bit 31 ) of EAX to every bit position 0 to 31 of EDX

Suppose sign bit bit 31 is 1 of eax register so edx

EDX = FFFFFFFFh

In our program

EAX = 212 0000 0000 0000 0000 0000 0000 1101 0100 in binary

Sign bit is 0 of eax register

EDX = 00000000h

EDX : EAX = 00000000h : 000000D4 h

Next instruction

DIV EBX

this instruction divide the value of EDX : EAX by EBX

EDX : EAX / EBX

Reminder in EDX

Quotient stored in EAX

212/19 quotient = 11 reminder =3

EDX = 3

EAX = 11

EBX = 19

Please upvoe . Comment if any query .