Execution model
Step accounting
Section titled “Step accounting”| Event | Cost |
|---|---|
| Executed instruction or terminator | One step |
| Call | One step |
| Callee return | One step |
| Argument setup or edge binding | Free |
The budget is checked before each step. A return on the final available step succeeds; a zero step budget times out immediately after input validation.
Outcomes and backends
Section titled “Outcomes and backends”An execution is completed, trapped, timed out, or invalid. CPU, CUDA, and LLVM implementations preserve the same configured step budget.
Call depth
Section titled “Call depth”One global step budget covers the whole call tree. Entry depth is one.
- The supported maximum call depth is 1,024.
- A zero call depth times out after validation.
- An attempted call at the maximum depth consumes its call step and yields a depth timeout.
- CLI
rundefaults to a call-depth limit of 64 and uses explicit heap frames rather than host recursion.
For the language-level call rules and backend restrictions, see Functions and calls.