Re: [Qemu-devel] qemu-mips strange jump !!!

["andrzej zaborowski" <balrogg@gmail.com>]

2008/12/27 andrzej zaborowski <balrogg@gmail.com>:
> 2008/12/27 Laurent Desnogues <laurent.desnogues@gmail.com>:
>> On Fri, Dec 26, 2008 at 7:36 PM, Alessandro Montano <alex@exit.it> wrote:
>>> This is my first post, so sorry for any error ...
>>> I'm developing a DVB-S emulator based on qemu-mips.
>>> I'm adding all the device, once a time, but I notice a strange problem that
>>> crashes my emulator.
>>>
>>> It seems to do  bad jumps!
>>>
>>> In brief ... I run this command
>>> *./bin/-qemu-system-mips -L . mips_bios.bin -d int,exec,op,in_asm
>>> *and it genereates this log
>>>
>>> IN:
>>> 0x80071fc4:  lui    at,0x8007
>>> 0x80071fc8:  lw    a1,0xC094(at)
>>> 0x80071fcc:  lui    a0,0x8007
>>> 0x80071fd0:  addiu    a0,a0,0xD060
>>> 0x80071fd4:  jal    0x8006d76c  <-  this is the right address
>>> 0x80071fd8:  nop
>> [...]
>>> IN:
>>> 0x8006d968:  andi    t9,t9,0xdf  <-  but this is a wrong jump !!!
>>> 0x8006d96c:  j    0x8006d90c
>>> 0x8006d970:  ori    t9,t9,0x20
>>
>> You can't rely on logs to see the flow of a program.
>
> Not with "in_asm" alone, but "exec" should show the flow of execution,
> except DEBUG_EXEC is undefined by default.

Actually no, Laurent pointed out that even this will not show what I
would expect when TBs are chained.

Cheers