Immediate branch offset

[Alexis BRENON <abrenon@wyplay.com>]

Hi everyone,

I'm new on the list, so I'll make a short introduction of me.
First of all, I'm french, so, please, be indulgent for my english 
mistakes...
I'm working on the Pypy project, to create a MIPS backend (a MIPS JIT).

To create the JIT, I have to load some MIPS instruction directly in 
memory without passing through a .asm file or else. So, I cannot set 
some labels. So to make some branches, I try to load the equivalent 
instruction of :
     bne $t0, $t1, -8
to go back, just before the bne instruction, if $t0 and $t1 are equals. 
But when it run, I've got an illegal instruction error.
To debug, I write a small program in the MARS MIPS simulator with this 
instruction. But when compiling, assembler says me that -8 is an operand 
of incorrect type.
I would like to know if it's possible to make a branch, with an 
immediate offset, or have I to always provide a label ?

I hope my question is clear.
Thanks for your attention, and for your answer :-p

Alexis BRENON

P.S. I try to go to the IRC channel, but I receive '#mipslinux :Cannot 
send to channel' every time  I send message. Is there any particular 
process to join the channel ?