addr_size = 4
int32_size = 4
.data

message: .asciz "Hello, World!\n"

.text
.global _start
_start:
  pushl  $message
  call   sub1
  addl   $4,%esp
  
  movl   $0,%ebx
  movl   $1,%eax
  int    $0x80
  
sub1:
  oldBP = 0
  retAddr = oldBP + 4
  pMess = retAddr + addr_size
  pChar = oldBP - addr_size
  
  pushl  %ebp
  movl   %esp,%ebp # snapshot of SP as frame pointer
  
  addl   $pChar,%esp # reserve for pChar
  
  movl   pMess(%ebp),%eax
  movl   %eax,pChar(%ebp) # pChar = pMess
  
anotherChar:
  movl   pChar(%ebp),%eax
  cmpb   $0,(%eax)
  jz     noMoreChar
  
  # need to print whatever eax points to
  movl   %eax,%ecx
  movl   $1,%edx
  movl   $1,%ebx
  movl   $4,%eax
  int    $0x80   # write(1, pChar, 1)
  
  addl   $1,pChar(%ebp)
  jmp    anotherChar
  
noMoreChar:
  
  
  
  subl   $pChar, %esp # free the four bytes reserved for pChar
  popl   %ebp
  ret