assign value to struct variable

To assign a value to a struct variable in Assembly language, you need to follow a specific set of steps. Here is an example of how you can assign a value to a struct variable:

  1. Define the struct: Define the structure of the variable by specifying the size and layout of its members. For example, you can define a struct with two members, 'name' and 'age', like this:
my_struct:
    .asciz "John"    # member 'name'
    .byte 25         # member 'age'
  1. Access the struct variable: Use the appropriate addressing mode to access the struct variable. For example, if the struct variable is stored at the memory address 'my_struct', you can access it using the appropriate addressing mode, such as 'lea' (load effective address) or 'mov' (move).
lea rdi, my_struct       # load the address of my_struct into rdi
  1. Assign values to the struct members: Use the appropriate instructions to assign values to the struct members. For example, you can use the 'mov' instruction to move a value into a specific offset within the struct.
mov byte ptr [rdi + 8], 30    # assign the value 30 to the 'age' member of my_struct
  1. Access the struct members: Use the appropriate instructions to access the struct members. For example, you can use the 'mov' instruction to move the value of a specific offset within the struct into a register.
mov al, byte ptr [rdi]    # move the value of the 'name' member of my_struct into the AL register

That's it! You have successfully assigned a value to a struct variable in Assembly language. Remember to adjust the offsets and sizes according to the specific layout of your struct.