Is the disassembled code in att syntax guaranteed to generate the same machine code?

[Peng Yu]

Using the att syntax, the disassembled code is the same as the
original assembly code in this example.

Is it the case that the disassembled code in att syntax guaranteed to
be used to generate the same machine code?

$ objdump -w -d a.out
...
   0:    66 0f 1f 04 00           nopw   (%rax,%rax,1)
$ cat 1.asm
nopw   (%rax,%rax,1)
$ as 1.asm
$ objdump -w -d a.out
...
   0:    66 0f 1f 04 00           nopw   (%rax,%rax,1)

-- 
Regards,
Peng