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## add the first 10 numbers, and return the result in the exit code
#
# To run:
#   $ subx translate ex3.subx ex3
#   $ subx run ex3
# Expected result:
#   $ echo $?
#   55

== 0x08048054  # code segment, after leaving room for ELF header
# instruction                     effective address                                         operand     displacement    immediate
# op          subop               mod           rm32          base      index     scale     r32
# 1-3 bytes                                                                                             0/1/2/4 bytes   0/1/2/4 bytes
  # result: EBX = 0
# 0: e_entry = 0x08048054
  bb                                                                                                                    0/imm32       # copy 0 to EBX
  # counter: ECX = 1
  b9                                                                                                                    1/imm32       # copy 1 to ECX

# 10: loop: 0x0804805e
  # while (ECX <= 10)
  81            7/subop/compare   3/mod/direct  1/rm32/ecx                                                              10/imm32      # compare ECX, 10/imm
  7f                                                                                                    10/disp8                      # jump-if-greater exit
  # EBX += ECX
  01                              3/mod/direct  3/rm32/ebx                                  1/r32/ecx                                 # add ECX to EBX
  # ECX++
  81            0/subop/add       3/mod/direct  1/rm32/ecx                                                              1/imm32       # add 1 to ECX
  # loop
  eb                                                                                                    -18/disp8                     # jump loop

# 28: exit: 0x08048070
  # exit(EBX)
  b8                                                                                                                    1/imm32       # copy 1 to EAX
  cd                                                                                                                    0x80/imm8     # int 80h

# vim:ft=subx:nowrap