IRTCxxxx does have separate code and data spaces as it is compiling for the MSP430.
The words C@, C!, @, !, 2@, 2!, FILL, ERASE, BLANK, CMOVE, ACQUIRE and RELINQUISH operate on the RAM space. But the code memory space uses C@, @, ,-T , C,-T and FLASH!
R8 Scratch N
R5 DP Data Stack Pointer
R7 TOS Top Stack Item
R4 UP USER Pointer
R6 RESOLVE Pointer for Multi-Tasking