Writing an Assembly Program Without Symbols

   Although  Assembly  language is low level, it still abstracts quite a lot.
   You can remove some of this abstraction by not using symbols. This  brings
   you slightly closer to human readable machine code.

   Writing  code  without  symbols is quite easy on ARM. All instructions are
   four bytes long, so you basically count the lines, multiply  it  by  four,
   then  add  it  to the entry point for the address.  Here is an example for
   printing "Hello, World!":

     @ A "Hello World" program without symbols for Linux ARM.
     @ To create an executable, run:
     @   as -o hello.o hello.s
     @   ld -e 65620 -o hello hello.o
     .sect .text
     mov     r7, $4          @ Setup service call 4 (write)
     mov     r0, #1          @ Parameter 1 - file descripter 1 = STDOUT
     ldr     r1, [pc, #16]   @ Paremeter 2 - address of string address = PC
                             @ (current byte from entry + 4, so 65636) + 16
     mov     r2, #14         @ Parameter 3 - length of string
     swi     #0              @ Ask Linux kernel to write to STDOUT
     mov     r7, #1          @ Setup service call 1 (exit)
     mov     r0, #0          @ Parameter 1 - 0 = normal exit
     swi     #0              @ Ask Linux kernel to terminate this program
     .long   65656           @ String address = 65620 + 36 (bytes from entry)
     .ascii  "Hello, World!"
     .byte   10              @ New-line character

   On 80386, it's significantly harder. Each instruction is 1-5  bytes  long.
   The exact length depends on the instruction and its arguments, if any.  As
   a result, you must calculate the length of each instruction one by one be-
   fore you can add them.
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