1 ## print out a (global variable) string to stdout 2 # 3 # To run: 4 # $ subx translate ex6.subx ex6 5 # $ subx run ex6 6 # Hello, world! 7 8 == 0x08048074 # code segment, after leaving room for ELF header and segment headers 9 # instruction effective address operand displacement immediate 10 # op subop mod rm32 base index scale r32 11 # 1-3 bytes 3 bits 2 bits 3 bits 3 bits 3 bits 2 bits 2 bits 0/1/2/4 bytes 0/1/2/4 bytes 12 13 ## write(stdout, x, 1) 14 # fd = 1 (stdout) 15 bb/copy 1/imm32 # copy 1 to EBX 16 # initialize x (location to write result to) 17 b9/copy 0x08049097/imm32 # copy to ECX 18 # initialize size 19 ba/copy 0x08049093/imm32 # copy to EDX 20 8b/copy 0/mod/indirect 2/rm32/edx 2/r32/edx # copy *EDX to EDX 21 # write(fd, x, size) 22 b8/copy 4/imm32 # copy 4 to EAX 23 cd/syscall 0x80/imm8 # int 80h 24 25 ## exit(EBX) 26 b8/copy 1/imm32 # copy 1 to EAX 27 cd/syscall 0x80/imm8 # int 80h 28 29 == 0x08049093 # data segment 30 # size of string 31 0e 00 00 00 32 # string 33 48 65 6c 6c 6f 2c 20 77 6f 72 6c 64 21 0a 00 34 # h e l l o , ␣ w o r l d ! newline null 35 36 # vim:ft=subx:nowrap