58 lines
2.1 KiB
Rust
58 lines
2.1 KiB
Rust
use prometeu_bytecode::isa::core::{CoreOpCode, CoreOpCodeSpecExt};
|
|
use prometeu_hal::{HostContext, HostReturn, NativeInterface, SyscallId};
|
|
use prometeu_vm::{BudgetReport, LogicalFrameEndingReason, VirtualMachine};
|
|
|
|
#[test]
|
|
fn scheduler_wake_and_ready_order_is_deterministic() {
|
|
// Black-box determinism: run a tiny program twice and ensure it yields the same sequence
|
|
// of LogicalFrameEndingReason for identical budgets.
|
|
|
|
fn emit(op: CoreOpCode, imm: Option<&[u8]>, out: &mut Vec<u8>) {
|
|
out.extend_from_slice(&(op as u16).to_le_bytes());
|
|
let need = op.spec().imm_bytes as usize;
|
|
match (need, imm) {
|
|
(0, None) => {}
|
|
(n, Some(bytes)) if bytes.len() == n => out.extend_from_slice(bytes),
|
|
(n, Some(bytes)) => {
|
|
panic!("imm size mismatch for {:?}: need {}, got {}", op, n, bytes.len())
|
|
}
|
|
(n, None) => panic!("missing imm for {:?}: need {} bytes", op, n),
|
|
}
|
|
}
|
|
|
|
struct NoopNative;
|
|
impl NativeInterface for NoopNative {
|
|
fn syscall(
|
|
&mut self,
|
|
_id: SyscallId,
|
|
_args: &[prometeu_bytecode::Value],
|
|
_ret: &mut HostReturn,
|
|
_ctx: &mut HostContext,
|
|
) -> Result<(), prometeu_hal::vm_fault::VmFault> {
|
|
Ok(())
|
|
}
|
|
}
|
|
|
|
// Program: FRAME_SYNC; HALT
|
|
let mut rom = Vec::new();
|
|
emit(CoreOpCode::FrameSync, None, &mut rom);
|
|
emit(CoreOpCode::Halt, None, &mut rom);
|
|
|
|
let run_once = || -> Vec<LogicalFrameEndingReason> {
|
|
let mut vm = VirtualMachine::new(rom.clone(), vec![]);
|
|
vm.prepare_call("0");
|
|
let mut native = NoopNative;
|
|
let mut ctx = HostContext::new(None);
|
|
let mut reasons = Vec::new();
|
|
let r1: BudgetReport = vm.run_budget(10, &mut native, &mut ctx).unwrap();
|
|
reasons.push(r1.reason);
|
|
let r2: BudgetReport = vm.run_budget(10, &mut native, &mut ctx).unwrap();
|
|
reasons.push(r2.reason);
|
|
reasons
|
|
};
|
|
|
|
let a = run_once();
|
|
let b = run_once();
|
|
assert_eq!(a, b, "execution reasons must be deterministic");
|
|
}
|