SignalGP Instruction Set Details
Here, we provide details about the SignalGP instruction set used in our experiments. For a detailed description of the SignalGP virtual hardware, please refer to (Lalejini and Ofria, 2018)
Throughout this document, we use the following abbreviations in our descriptions:
ARG1,ARG2,ARG3: First, second, and third argument for an instruction.WM: Indicates working memory.WM[i]: indicates accessing working memory at locationi.
IM: Indicates input memory.IM[i]: indicates accessing output memory at locationi.
OM: Indicates output memory.OM[i]: indicates accessing output memory at locationi.
SM: Indicates shared memory.SM[i]: indicates accessing shared memory at locationi.
EOF: Indicates the end of a function.NOP: Indicates no operation. (do nothing)
Standard Instruction Set
Below is a table describing the set of standard SignalGP instructions included in our experiments.
| Instruction | # Arguments | Uses Tag? | Description |
|---|---|---|---|
Inc |
1 | No | WM[ARG1] = WM[ARG1] + 1 |
Dec |
1 | No | WM[ARG1] = WM[ARG1] - 1 |
Not |
1 | No | WM[ARG1] = !WM[ARG1] Logically toggle WM[ARG1] |
Add |
3 | No | WM[ARG3] = WM[ARG1] + WM[ARG2] |
Sub |
3 | No | WM[ARG3] = WM[ARG1] - WM[ARG2] |
Mult |
3 | No | WM[ARG3] = WM[ARG1] * WM[ARG2] |
Div |
3 | No | WM[ARG3] = WM[ARG1] / WM[ARG2] Safe; division by 0 is NOP. |
Mod |
3 | No | WM[ARG3] = WM[ARG1] % WM[ARG2] Safe |
TestEqu |
3 | No | WM[ARG3] = (WM[ARG1] == WM[ARG2]) |
TestNEqu |
3 | No | WM[ARG3] = (WM[ARG1] != WM[ARG2]) |
TestLess |
3 | No | WM[ARG3] = (WM[ARG1] < WM[ARG2]) |
If |
1 | No | If WM[ARG1] != 0, proceed; else, skip until next Close or EOF |
While |
1 | No | If WM[ARG1] != 0, loop; else, skip until next Close or EOF |
Countdown |
1 | No | Same as While, but decrements WM[ARG1] |
Close |
0 | No | Indicates end of looping or conditional instruction block |
Break |
0 | No | Break out of current loop |
Call |
0 | Yes | Call function referenced by tag |
Return |
0 | No | Return from current function |
Fork |
0 | Yes | Calls function referenced by tag on a new thread |
Terminate |
0 | No | Terminates thread on which this instruction is executed. |
SetMem |
2 | No | WM[ARG1] = ARG2 |
CopyMem |
2 | No | WM[ARG1] = WM[ARG2] |
SwapMem |
2 | No | Swap(WM[ARG1], WM[ARG2]) |
Input |
2 | No | WM[ARG2] = IM[ARG1] |
Output |
2 | No | OM[ARG2] = WM[ARG1] |
Commit |
2 | No | SM[ARG2] = WM[ARG1] |
Pull |
2 | No | WM[ARG2] = SM[ARG1] |
Nop |
0 | No | No-operation |
Experiment-Specific Instructions
Below is a table describing instructions used in our experiments that are specific to both the changing environment and distracting environment problems.
| Instruction | # Arguments | Uses Tag? | Description |
|---|---|---|---|
SenseEnvState0 |
1 | No | WM[ARG1] = 1 if environment in state 0; else, WM[ARG1] = 0 |
SenseEnvState1 |
1 | No | WM[ARG1] = 1 if environment in state 1; else, WM[ARG1] = 0 |
SenseEnvState2 |
1 | No | WM[ARG1] = 1 if environment in state 2; else, WM[ARG1] = 0 |
SenseEnvState3 |
1 | No | WM[ARG1] = 1 if environment in state 3; else, WM[ARG1] = 0 |
SenseEnvState4 |
1 | No | WM[ARG1] = 1 if environment in state 4; else, WM[ARG1] = 0 |
SenseEnvState5 |
1 | No | WM[ARG1] = 1 if environment in state 5; else, WM[ARG1] = 0 |
SenseEnvState6 |
1 | No | WM[ARG1] = 1 if environment in state 6; else, WM[ARG1] = 0 |
SenseEnvState7 |
1 | No | WM[ARG1] = 1 if environment in state 7; else, WM[ARG1] = 0 |
SenseEnvState8 |
1 | No | WM[ARG1] = 1 if environment in state 8; else, WM[ARG1] = 0 |
SenseEnvState9 |
1 | No | WM[ARG1] = 1 if environment in state 9; else, WM[ARG1] = 0 |
SenseEnvState10 |
1 | No | WM[ARG1] = 1 if environment in state 10; else, WM[ARG1] = 0 |
SenseEnvState11 |
1 | No | WM[ARG1] = 1 if environment in state 11; else, WM[ARG1] = 0 |
SenseEnvState12 |
1 | No | WM[ARG1] = 1 if environment in state 12; else, WM[ARG1] = 0 |
SenseEnvState13 |
1 | No | WM[ARG1] = 1 if environment in state 13; else, WM[ARG1] = 0 |
SenseEnvState14 |
1 | No | WM[ARG1] = 1 if environment in state 14; else, WM[ARG1] = 0 |
SenseEnvState15 |
1 | No | WM[ARG1] = 1 if environment in state 15; else, WM[ARG1] = 0 |
SetState0 |
0 | No | Set internal state to 0 |
SetState1 |
0 | No | Set internal state to 1 |
SetState2 |
0 | No | Set internal state to 2 |
SetState3 |
0 | No | Set internal state to 3 |
SetState4 |
0 | No | Set internal state to 4 |
SetState5 |
0 | No | Set internal state to 5 |
SetState6 |
0 | No | Set internal state to 6 |
SetState7 |
0 | No | Set internal state to 7 |
SetState8 |
0 | No | Set internal state to 8 |
SetState9 |
0 | No | Set internal state to 9 |
SetState10 |
0 | No | Set internal state to 10 |
SetState11 |
0 | No | Set internal state to 11 |
SetState12 |
0 | No | Set internal state to 12 |
SetState13 |
0 | No | Set internal state to 13 |
SetState14 |
0 | No | Set internal state to 14 |
SetState15 |
0 | No | Set internal state to 15 |
References
Lalejini, A., & Ofria, C. (2018). Evolving Event-driven Programs with SignalGP. In Proceedings of the Genetic and Evolutionary Computation Conference. ACM. Pre-print here.