4.9 Context Manipulation

Remove two elements S0 and S1. Restore the context of the calling procedure by loading FP with S0 and then perform a branch to S1. S1 is usually a return address which was previously saved by a CALL or CALR instruction.

Remove three elements S0, S1, S2. Restore the instance context of the caller by loading SELF with S0, restore the stack frame of the caller by loading FP with S1 and then perform a branch to S2. S2 is usually a return address which was previously saved by a CALL or CALR instruction.

Push the context of the calling procedure (FP) and create a fresh procedure context by loading FP with SP.

First push the context of the calling procedure (FP) and create a fresh procedure context by loading FP with SP. Then push the instance context of the sending method or procedure (SELF) and shift the instance context by loading SELF with the machine word pointed to by FP+2BPW (the last argument passed to the answering method).