Rounding to a 2G-byte boundary

[Mark Boonie]

I have macro that currently looks like this:

         MACRO ,
         RNDUP &REG,&BOUND
         AGHI  &REG,&BOUND-1
         RNDDOWN &REG,&BOUND
         MEND  ,

I was trying to update it to use the newer ALGFI instruction like this:

         MACRO ,
         RNDUP &REG,&BOUND
         ALGFI &REG,&BOUND-1
         RNDDOWN &REG,&BOUND
         MEND  ,

However, I can't specify the boundary as a symbol equated to 2G (e.g., 
SEGTBLRANGE EQU X'80000000') without getting an assembler error due to an 
overflow in an intermediate value.  Does anyone have any alternative ways 
to do this?  I really need the ability to handle 2G.  Thanks.

- mb