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Diffstat (limited to 'subx/examples/ex6.subx')
| -rw-r--r-- | subx/examples/ex6.subx | 36 |
1 files changed, 36 insertions, 0 deletions
diff --git a/subx/examples/ex6.subx b/subx/examples/ex6.subx new file mode 100644 index 00000000..4c75c617 --- /dev/null +++ b/subx/examples/ex6.subx @@ -0,0 +1,36 @@ +## print out a (global variable) string to stdout +# +# To run: +# $ subx translate ex6.subx ex6 +# $ subx run ex6 +# Hello, world! + +== 0x08048074 # code segment, after leaving room for ELF header and segment headers +# instruction effective address operand displacement immediate +# op subop mod rm32 base index scale r32 +# 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 + + ## write(stdout, x, 1) + # fd = 1 (stdout) + bb/copy 1/imm32 # copy 1 to EBX + # initialize x (location to write result to) + b9/copy 0x08049097/imm32 # copy to ECX + # initialize size + ba/copy 0x08049093/imm32 # copy to EDX + 8b/copy 0/mod/indirect 2/rm32/EDX 2/r32/EDX # copy *EDX to EDX + # write(fd, x, size) + b8/copy 4/imm32 # copy 4 to EAX + cd/syscall 0x80/imm8 # int 80h + + ## exit(EBX) + b8/copy 1/imm32 # copy 1 to EAX + cd/syscall 0x80/imm8 # int 80h + +== 0x08049093 # data segment +# size of string +0e 00 00 00 +# string + 48 65 6c 6c 6f 2c 20 77 6f 72 6c 64 21 0a 00 +# h e l l o , ␣ w o r l d ! newline null + +# vim:ft=subx:nowrap |