[LinuxBIOS] General question abouts jumps in machine code
Stefan Reinauer
stepan at coresystems.de
Fri Jun 29 20:17:06 CEST 2007
* Shadravan Fontanov <shadravan_f at yahoo.com> [070629 19:03]:
> Exactly 64 times 0x90, fine... The next code after the last 0x90 is 0xe9. Look
> at "Intel Architecture Software Developers Manual Vol2" tells: its jump
> instruction, the next two bytes (bd ff) specify the relative address to jump.
> bdff must be in second complement and represent minus 4201. But offset 4201
> does not jumps to the start of the NOP sequence, it jumps to a very smaller
> address...
The number is little endian, so it is 0xffbd, which is 2 bytes short of
0xffc0, which is -64 in 16bit hex.
Stefan
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