System Debug Reference Manual (32650-90888)

Chapter 4 125
System Debug Command Specifications :-Exit
DR
The following registers are pseudo-registers. They are not defined in the Precision
Architecture, but are terms used in the procedure calling conventions document and by the
language compilers. They are provided for convenience. They are computed based on stack
unwind information. They may not be modified.
The following registers are known as the Space Registers. Registers SR4 through SR7 are
used for short pointer addressing:
R3 none dm General register 3
[vellip]
R22 none dm General register 22
R23 ARG3 dm Argument register 3
R24 ARG2 dm Argument register 2
R25 ARG1 dm Argument register 1
R26 ARG0 dm Argument register 0
R27 DP dM Global data pointer
R28 RET1 dm Return register 1
R29 RET0 dm Return register 0
SL dm Static link
R30 SP dM Current stack pointer
R31 MRP dm Millicode return pointer
Table 4-2. Psuedo-Registers
Name Alias Access Description
RP none d Return pointer (not the same as R2)
PSP none d Previous stack pointer
Table 4-3. Space Registers
Name Alias Access Description
SR0 none dm Space register 0
SR1 SARG dm Space register argument
SRET dm Space return register
SR2 none dm Space register 2
SR3 none dm Space register 3
Table 4-1. General Registers
Name Alias Access Description