NonStop S-Series Server Description Manual (G06.24+)

Native Execution Mode

HP NonStop S-Series Server Description Manual—520331-003

7-3

Native Mode Uses RISC Register Conventions

%h 08007FF0. (Global data is not limited to 64 KB; with two instructions, any address

in the 4-gigabyte address space can be accessed.)

Up to four words or parameters can be passed to a procedure in a0 through a3, and

results are returned in registers v0 and v1. Procedures save and restore registers s0

through s8 (if they are used) and return sp to its original value. Registers t0 through t9

are used for procedure temporary usage.

Registers k0 and k1 are reserved for kernel exception handlers, and the assembler

temporary register (at) is reserved for short-term temporary storage.

Figure 7-1. RISC Registers Point to Global Data, Main Stack Tip, and Return

Address

Nonprivileged

Space

Global Data

Main Stack

Code

Regions

RISC Registers

VST311.vsd