Examples

# Prints "25" to stdout
# build: gcc -static print_example.s
.globl main
.section .data
fmt_int:
    .ascii "%d\n\0"
.section .text
main:
    movq stdout, %rdi     # arg1: FILE* stdout 
    movq $fmt_int, %rsi   # arg2: format string
    movq $25, %rdx        # arg3: integer to print
    movq $0, %rax         # no floating-point args (required by ABI)
    call fprintf          # fprintf(stdout, "%d\n", 25)

    mov $0, %rax
    ret

.globl main
.section .data
array_size:
    .quad 5
array:
    .quad 1, 3, 5, 7, 9
target:
    .quad 1

.section .text
main:
    jmp linear_search


linear_search: 
    mov array_size, %rcx   # counter
    mov target, %rdi       # target
    mov $0, %rbx           # zero our index i

loop_start:
    mov array(,%rbx,8), %rax  # if array[i] == target
    cmp %rdi, %rax            # jmp to found
    je found                  # else loop
loop_control:
    inc %rbx               # i++
    loop loop_start        # dec %rcx (real counter)
    jmp notfound           # logically not needed, just safer

found:
    mov %rbx, %rdi
    jmp final

notfound:
    mov $-1, %rdi
    jmp final

final:
    mov $60, %rax
    syscall
    ret