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x64 Assembly FizzBuzz(nostdlib version)
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// vim: ts=8 sw=8 | |
// build and execute | |
// $ gcc -nostdlib -static -s fizzbuzz.s -o fizzbuzz | |
// $ ./fizzbuzz | |
.section .rodata | |
.Sfizz: | |
.asciz "Fizz\n" | |
.Sbuzz: | |
.asciz "Buzz\n" | |
.Sfizzbuzz: | |
.asciz "FizzBuzz\n" | |
.data | |
.ds 14 | |
.Snumber: | |
.asciz "\n" | |
.text | |
.global _start | |
_start: | |
// loop index | |
xor %ebp, %ebp | |
.Lloop: | |
// increment loop index | |
inc %ebp | |
// check multiple of 15 | |
xor %edx, %edx | |
mov %ebp, %eax | |
mov $15, %ecx | |
div %ecx | |
lea .Sfizzbuzz(%rip), %rsi | |
test %edx, %edx | |
je .Loutput | |
// check multiple of 3 | |
xor %edx, %edx | |
mov %ebp, %eax | |
mov $3, %ecx | |
div %ecx | |
lea .Sfizz(%rip), %rsi | |
test %edx, %edx | |
je .Loutput | |
// check multiple of 5 | |
xor %edx, %edx | |
mov %ebp, %eax | |
mov $5, %ecx | |
div %ecx | |
lea .Sbuzz(%rip), %rsi | |
test %edx, %edx | |
je .Loutput | |
// convert number to string | |
lea .Snumber(%rip), %rsi | |
mov %ebp, %eax | |
mov $10, %ecx | |
.Ltostrloop: | |
xor %edx, %edx | |
div %ecx | |
add $'0', %edx | |
dec %rsi | |
mov %dl, (%rsi) | |
test %eax, %eax | |
jne .Ltostrloop | |
.Loutput: | |
// count output bytes | |
xor %edx, %edx | |
.Lcountloop: | |
mov (%rsi,%rdx), %al | |
inc %edx | |
test %al, %al | |
jne .Lcountloop | |
dec %edx | |
// write(1, %rsi, %rdx) | |
mov $1, %edi | |
mov $1, %eax | |
syscall | |
// check loop condition | |
cmp $40, %ebp | |
jl .Lloop | |
// exit(0) | |
xor %edi, %edi | |
mov $60, %eax | |
syscall |
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