fasm -- the almost perfect assembler

I once made a blog about how assembly is bloated so today I decided to try fasm, it was amazing, it's almost as efficient as C generated ELF,

For example, using NASM (or YASM but the difference is only 0.1 KB if not less) a Hello world program would look like this:

<code> <pre>

BITS 64

segment .text global _start

_start: mov rax, 1 mov rdi, 1 mov rsi, m mov rdx, ml syscall

1
2
3

mov rax, 60
mov rdi, 0
syscall

segment .rodata m: db "Hello world!", 10 ml: equ $ - m

</pre> </code>

And when compiled using:

1

$ nasm -felf64 a.asm && ld -o a a.o

Where a.asm is the assembly source code you see above you get a 8.7 KB binary

So now let's do the same but using FASM:

<code> <pre>

format ELF64 executable 3 segment readable executable

_start: mov rax, 1 mov rdi, 1 mov rsi, m mov rdx, ml syscall

1
2
3

mov rax, 60
mov rdi, 0
syscall

segment readable m: db "Hello world!", 10 ml = $ - m

</pre> </code>

The code hasn't changed much but when we compile this code using:

1

$ fasm a.asm && chmod a+rx ./a

Where a.asm is the assembly source code you see above you get a 235 B binary

That's literally 8.465 KB improvement for only changing 5 lines of code... That's only one byte larger than out source code -- 234 B

Crazy how fast, small and nice this assembler is, give it a try! :)