%Rn

(%R0 to %R15)

Represent the General Purpose Registers for the assembler or disassembly CU to which you are currently qualified. These symbols are not valid in a CU in any other language. In addition, these symbols are undefined in assembler and disassembly CUs that are not currently active or for which the applicable General Purpose Registers cannot be located. Registers can be located for active assembler and disassembly CUs only if:
  • The CU was in control when the user program was suspended, or
  • The CU was active in the call chain above the CU that was active when the user program was suspended and all programs in the call chain use standard linkage conventions in relation to R13, R14, and R15 and save all registers in a chained save area

To modify one of these registers, assign a value to the associated %Rn variable.

Usage notes

  • If you modify a %Rn register, the change is reflected when you resume program execution.
  • The use of these symbols is equivalent to the use of any register symbols defined in your program.
  • The %Rn symbols differ from the %GPRn symbols in that %GPRn represents the value that was actually in the hardware General Purpose Register when your user program was suspended, but %Rn represents the value associated in the assembler or disassembly CU to which you are currently qualified. If you are currently qualified to the CU that was active when your user program was suspended, %Rn and %GPRn are identical. However, if you are currently qualified to a CU that was in the call chain but was not the CU that was active when your program was suspended, %Rn and %GPRn will be different. If you are qualified to a CU that was not active when your program was suspended, %Rn is undefined.

Examples

LIST %R1 ;
%R7 = 0 ;