Help with accessing array elements in ASM

[bobspencerr]

Can anyone tell me how to use a variable position within ASM in PIC32 to access an array?
Here is the line that is causing me grief which accesses an array zservo one element at a time in a loop.

LHU R10, Offset(_zservo + 0)(GP)

I have tried substituting the +0 with a variable (R23) but it fails in the compiler.

LHU R10, Offset(_zservo + R23)(GP)


Is this even possible?
What is the (GP) part of the statement for?

[bobspencerr]

Thanks to anyone looking at this one but I have resolved it now.

Cheers