Load/store instructions are the only instructions accessing GM (implemented as I-structure storage)
Arithmetic/logical instructions operate on local memory (registers)
One-cycle instruction execution (except for load/store instructions)
No explicit matching unit: all operands associated with a sequential thread of computation are kept in a frame in local Program Memory (PM).
Continuation: an (IP;FP) pair
- IP serves to fetch the next instruction
- FP serves as the base for fetching and storing operands.
To make P-RISC multithreaded, the stack of frames is arranged as a tree of frames, and a separate continuation is associated with each thread.