Here is an example program in assembly language that decrements a loop counter:
```
section .data
section .bss
section .text
global _start
_start:
mov cx, 10 ; Initialize the loop counter to 10
loop_start:
dec cx ; Decrement the loop counter
cmp cx, 0 ; Check if the counter is zero
je loop_exit ; If the counter is zero, exit the loop
jmp loop_start ; Otherwise, continue looping
loop_exit:
; Your code to exit the loop goes here
; For example, you could print a message or
; perform some other action before exiting
; the program
mov eax, 1 ; Exit system call
xor ebx, ebx ; Exit status code
int 0x80 ; Call kernel
```
In this example, the program initializes the loop counter to 10 using the `mov` instruction, then enters a loop using the `jmp` instruction. At the beginning of each iteration of the loop, the program decrements the loop counter using the `dec` instruction, then checks whether the counter is zero using the `cmp` instruction. If the counter is zero, the program branches to the `loop_exit` label using the `je` instruction. Otherwise, the program jumps back to the beginning of the loop using the `jmp` instruction.
Note that the loop is implemented using conditional branching instructions (`je` and `jmp`). Other looping constructs, such as `for` or `while` loops, can be implemented using different instructions and constructs. The specific instructions used will depend on the requirements of the program and the architecture of the CPU being used.
Assembly program to decrement loop counter
1 answer