Title here
Summary here
For in Assembly Language
Assembly language doesn’t have high-level looping constructs like for loops. Instead, we use jumps and comparisons to create loops. Here’s an equivalent implementation of the various loop types in x86 assembly:
section .data
fmt db "%d", 10, 0 ; Format string for printf
section .text
global main
extern printf
main:
; The most basic type, with a single condition
mov ecx, 1 ; i := 1
loop1:
cmp ecx, 3 ; i <= 3
jg loop1_end
push ecx
push fmt
call printf
add esp, 8
inc ecx ; i = i + 1
jmp loop1
loop1_end:
; A classic initial/condition/after loop
mov ecx, 0 ; j := 0
loop2:
cmp ecx, 3 ; j < 3
jge loop2_end
push ecx
push fmt
call printf
add esp, 8
inc ecx ; j++
jmp loop2
loop2_end:
; Range over an integer
mov ecx, 0 ; i := 0
loop3:
cmp ecx, 3 ; i < 3
jge loop3_end
push ecx
push fmt
call printf
add esp, 8
inc ecx
jmp loop3
loop3_end:
; Infinite loop with break
mov eax, 0
loop4:
push eax
push fmt
call printf
add esp, 8
inc eax
cmp eax, 1 ; Simulate 'break' after first iteration
je loop4_end
jmp loop4
loop4_end:
; Loop with continue
mov ecx, 0 ; n := 0
loop5:
cmp ecx, 6 ; n < 6
jge loop5_end
test ecx, 1 ; if n % 2 == 0
jz loop5_continue
push ecx
push fmt
call printf
add esp, 8
loop5_continue:
inc ecx
jmp loop5
loop5_end:
retThis assembly code demonstrates various looping constructs equivalent to the original example:
- A basic loop with a single condition.
- A classic initial/condition/after loop.
- A loop that ranges over an integer.
- An “infinite” loop that breaks after one iteration.
- A loop that uses the concept of “continue” to skip even numbers.
Note that assembly language is much lower level than high-level languages. We have to manually manage the stack, call external functions (like printf), and use jumps and comparisons to control the flow of the program.
To run this program, you would need to assemble it into an object file, link it with the C library (for printf), and then execute the resulting binary. The exact commands may vary depending on your system and assembler, but it might look something like this:
$ nasm -f elf64 loops.asm
$ gcc -no-pie loops.o -o loops
$ ./loops
1
2
3
0
1
2
0
1
2
0
1
3
5Remember that assembly language is highly dependent on the specific architecture and calling conventions of your system. This example is for x86 assembly and may need adjustments for other architectures or systems.