rasm2 gives incorrect hexpairs

[ericfode]

rasm2 "mov al, cl" gives
89ff
rasm2 "pop al" gives
ff

root@protostar:~# rasm2 "mov al, cl"
89ff

yet for some reason it seems to be able to disassemble the opcode fine
root@protostar:~# rasm2 -d "88 c8"
mov al, cl

[ericfode]

it fails here to

root@protostar:# rasm2 "mov al, [ebx]"
8bfb
root@protostar:# rasm2 -d "8bfb"
mov edi, ebx

[radare]

The default assembler plugin for x86 is x86.nz which lacks support for 16bit opcodes. Im gonna implement it and commit it. But meanwhile you can use the x86.olly one:

rasm2 -a x86.olly ''mov al, cl"

'pop al' is an invalid instruction and its not handled by x86.nz

That plugin is under development and there's a testsuite aiming to check all those issues. There are several instructions that are not supported yet, but it works fine with r-egg to create programs.

Thanks for reporting

On Aug 1, 2012, at 22:36, Eric Fodereply@reply.github.com wrote:

rasm2 "mov al, cl" gives
89ff
rasm2 "pop al" gives
ff

root@protostar:~# rasm2 "mov al, cl"
89ff

yet for some reason it seems to be able to disassemble the opcode fine
root@protostar:~# rasm2 -d "88 c8"
mov al, cl

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