x86 Mnemonics 32-bit

Data Processing Instructions:

1. ADD (Addition)

   • Description: Adds two operands and stores the result in the destination operand.

   • Example: ADD EAX, EBX

     
     

     Adds the value in EBX to EAX, storing the result in EAX.

2. SUB (Subtraction)

   • Description: Subtracts the second operand from the first operand and stores the result in the destination operand.

   • Example: SUB EAX, EBX

     
     

     Subtracts the value in EBX from EAX and stores the result in EAX.

3. MUL (Unsigned Multiplication)

   • Description: Multiplies the accumulator register (EAX) by the operand, storing the result in EDX:EAX.

   • Example: MUL EBX

     
     

     Multiplies the value in EAX by EBX, storing the result in EDX:EAX.

4. IMUL (Signed Multiplication)

   • Description: Multiplies the accumulator register (EAX) by the operand, storing the result in EDX:EAX (signed).

   • Example: IMUL EAX, EBX

     
     

     Multiplies the value in EAX by EBX, storing the result in EDX:EAX.

5. DIV (Unsigned Division)

   • Description: Divides the value in the accumulator register (EDX:EAX) by the operand, storing the quotient in EAX and the remainder in EDX.

   • Example: DIV EBX

     
     

     Divides the value in EDX:EAX by EBX, storing the quotient in EAX and the remainder in EDX.

6. IDIV (Signed Division)

   • Description: Divides the value in the accumulator register (EDX:EAX) by the operand (signed division), storing the quotient in EAX and the remainder in EDX.

   • Example: IDIV EBX

     
     

     Divides the value in EDX:EAX by EBX, storing the quotient in EAX and the remainder in EDX.

7. INC (Increment)

   • Description: Increments the operand by 1.

   • Example: INC EAX

     
     

     Increments the value in EAX by 1.

8. DEC (Decrement)

   • Description: Decrements the operand by 1.

   • Example: DEC EAX

     
     

     Decrements the value in EAX by 1.

9. AND (Bitwise AND)

   • Description: Performs a bitwise AND between two operands and stores the result in the destination operand.

   • Example: AND EAX, EBX

     
     

     Performs a bitwise AND between EAX and EBX, storing the result in EAX.

10. OR (Bitwise OR)

    • Description: Performs a bitwise OR between two operands and stores the result in the destination operand.

    • Example: OR EAX, EBX

      
      

      Performs a bitwise OR between EAX and EBX, storing the result in EAX.

11. XOR (Bitwise XOR)

    • Description: Performs a bitwise XOR between two operands and stores the result in the destination operand.

    • Example: XOR EAX, EBX

      
      

      Performs a bitwise XOR between EAX and EBX, storing the result in EAX.

12. NOT (Bitwise NOT)

    • Description: Performs a bitwise NOT (inversion) of the operand.

    • Example: NOT EAX

      
      

      Performs a bitwise NOT on EAX, inverting all bits.

13. NEG (Negate)

    • Description: Negates the operand (computes the two's complement).

    • Example: NEG EAX

      
      

      Negates the value in EAX.

Shift and Rotate Instructions:

1. SHL (Shift Left)

   • Description: Shifts the bits of the operand to the left, inserting zeros into the least significant bits.

   • Example: SHL EAX, 1

     
     

     Shifts the bits of EAX to the left by 1, filling with zeros.

2. SHR (Shift Right)

   • Description: Shifts the bits of the operand to the right, inserting zeros into the most significant bits.

   • Example: SHR EAX, 1

     
     

     Shifts the bits of EAX to the right by 1, filling with zeros.

3. SAR (Arithmetic Shift Right)

   • Description: Shifts the bits of the operand to the right, preserving the sign bit (for signed integers).

   • Example: SAR EAX, 1

     
     

     Shifts the bits of EAX to the right by 1, preserving the sign bit.

4. ROL (Rotate Left)

   • Description: Rotates the bits of the operand to the left.

   • Example: ROL EAX, 1

     
     

     Rotates the bits of EAX to the left by 1.

5. ROR (Rotate Right)

   • Description: Rotates the bits of the operand to the right.

   • Example: ROR EAX, 1

     
     

     Rotates the bits of EAX to the right by 1.

Load and Store Instructions:

1. MOV (Move)

   • Description: Copies data from one operand to another.

   • Example: MOV EAX, EBX

     
     

     Copies the value in EBX to EAX.

2. PUSH (Push onto stack)

   • Description: Pushes a value onto the stack.

   • Example: PUSH EAX

     
     

     Pushes the value in EAX onto the stack.

3. POP (Pop from stack)

   • Description: Pops a value from the stack into a register.

   • Example: POP EAX

     
     

     Pops the top value from the stack into EAX.

4. LEA (Load Effective Address)

   • Description: Loads the effective address of a memory operand into a register.

   • Example: LEA EAX, [EBX + ECX*4]

     
     

     Loads the address calculated from EBX + ECX*4 into EAX.

5. MOVZX (Move with Zero Extension)

   • Description: Moves a value and zero-extends it to a larger size.

   • Example: MOVZX EAX, BYTE [EBX]

     
     

     Moves the byte at the memory address in EBX into EAX, zero-extending it.

6. MOVSX (Move with Sign Extension)

   • Description: Moves a value and sign-extends it to a larger size.

   • Example: MOVSX EAX, BYTE [EBX]

     
     

     Moves the byte at the memory address in EBX into EAX, sign-extending it.

Branch Instructions:

1. JMP (Jump)

   • Description: Unconditionally jumps to a target address.

   • Example: JMP label

     
     

     Jumps to the instruction at the label.

2. JE (Jump if Equal)

   • Description: Jumps to a target address if the zero flag is set (i.e., if the two operands were equal).

   • Example: JE label

     
     

     Jumps to the label if the zero flag is set.

3. JNE (Jump if Not Equal)

   • Description: Jumps to a target address if the zero flag is cleared (i.e., if the operands were not equal).

   • Example: JNE label

     
     

     Jumps to the label if the zero flag is cleared.

4. JL (Jump if Less)

   • Description: Jumps to a target address if the signed comparison is less.

   • Example: JL label

     
     

     Jumps to the label if the signed comparison is less.

5. JLE (Jump if Less or Equal)

   • Description: Jumps to a target address if the signed comparison is less or equal.

   • Example: JLE label

     
     

     Jumps to the label if the signed comparison is less or equal.

6. JGE (Jump if Greater or Equal)

   • Description: Jumps to a target address if the signed comparison is greater or equal.

   • Example: JGE label

     
     

     Jumps to the label if the signed comparison is greater or equal.

7. JMP (Jump)

   • Description: An unconditional jump to a specified address.

   • Example: JMP label

     
     

     Jumps to label unconditionally.

Comparison Instructions:

1. CMP (Compare)

   • Description: Compares two operands by subtracting them and updating the flags.

   • Example: CMP EAX, EBX

     
     

     Compares the values in EAX and EBX.

2. TEST (Test)

   • Description: Performs a bitwise AND between two operands and updates the flags.

   • Example: TEST EAX, EBX

     
     

     Performs a bitwise AND between EAX and EBX and updates the flags.

Stack Management Instructions:

1. CALL (Call Function)

   • Description: Calls a function, pushing the return address onto the stack.

   • Example: CALL func

     
     

     Calls the function func.

2. RET (Return from Function)

   • Description: Pops the return address from the stack and returns to that address.

   • Example: RET

     
     

     Pops the return address and returns to it.

Miscellaneous Instructions:

1. NOP (No Operation)

   • Description: Does nothing; typically used for padding or alignment.

   • Example: NOP

     
     

     No operation.

2. HLT (Halt)

   • Description: Stops the processor.

   • Example: HLT

     
     

     Halts execution.

3. CLD (Clear Direction Flag)

   • Description: Clears the direction flag, ensuring string operations auto-increment addresses.

   • Example: CLD

     
     

     Clears the direction flag.

4. STD (Set Direction Flag)

   • Description: Sets the direction flag, ensuring string operations auto-decrement addresses.

   • Example: STD

     
     

     Sets the direction flag.

System Instructions:

1. SYSENTER (System Enter)

   • Description: Used for fast system calls.

   • Example: SYSENTER

2. SYSCALL (System Call)

   • Description: Triggers a system call.

   • Example: SYSCALL

     
     

     Issues a system call to the operating system.

This list covers many of the essential x86 instructions, including those for arithmetic, logic, shifting, branching, stack management, system calls, and more.