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Comment by 2bluesc | Hacker News Reader

Went to see the printf or puts implementation rather then just calling a library function. Then saw Intel assembly and reminded myself why I've never wrestled with it.

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This is the GNU assembler AT&T syntax though, which is known to be horrendous. Other assemblers have much nicer syntax.

Agreed; most programmers I know who write a lot of x86 Asm tend to stick with the Intel syntax. I've never found the "it's easier to parse" argument for AT&T syntax particularly convincing, especially as GAS is written in C while some of the Intel syntax assemblers existing at the time were themselves written in x86 Asm. Neither is the "it makes it more consistent with the other arch's assemblers" - just look at GAS' syntax for MIPS and ARM. It seems to me like someone was really obsessed with the SPARC syntax (which I find roughly as horrendous.)

http://x86asm.net/articles/what-i-dislike-about-gas/

I don't think either syntax is nicer than the other. It's just a matter personal preference and familiarity.

Intel syntax has more intuitive memory access syntax:

AT&T syntax:

    movl mem_location(%ebx,%ecx,4), %eax

Intel syntax:

    mov eax, [ebx + ecx*4 + mem_location]

The other differences are minor compared to that, IMHO.

https://en.wikipedia.org/wiki/X86_assembly_language#Syntax

I can agree with most of that, except for the fact that Intel arguments are backwards. That throws me off every time. I don't know of any other assembler syntax that uses that argument order.

For me, I remember the notation by correlating it to its "high-level" equivalent.

   mov eax, [ ptr ]

is like

   eax = *ptr;  // or, eax = ptr[ 0 ];

The offset/multiplier memory addressing format for AT&T syntax was always more troubling for me. Coming from a TASM/MASM/NASM/PASCAL/x86 background first, it felt "icky" to put offsets outside of the "brackets" (or parenthesis, as it were) [0][1].

[0] https://github.com/lpsantil/rt0/blob/master/src/lib/00_start...

[1] https://github.com/lpsantil/rt0/blob/master/src/lib/00_start...

Standard ARM, MIPS, PowerPC, x86, and Z80 Asm syntax all have the destination on the far left.

68k, Alpha, PDP-11, SPARC, and VAX have the destination on the far right.

The order is probably as contentious as the great endianness debate, but I think one of the most awkward parts of having src, dst order is that subtraction looks backwards. I prefer dst, src because it corresponds closely with the direction of assignment in higher-level languages:

    op a, b, c       ; a = b op c
    op a, b          ; a op= b

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