pr5.6

crates/console/prometeu-vm/tests/syscall_multi_return.rs

@@ -0,0 +1,55 @@
+//! Deterministic tests for multi-return syscalls with the slot-based ABI.
+use prometeu_bytecode::isa::core::CoreOpCode as OpCode;
+use prometeu_bytecode::{FunctionMeta, Value};
+use prometeu_vm::{HostContext, HostReturn, NativeInterface, VirtualMachine};
+use prometeu_hal::vm_fault::VmFault;
+
+fn enc_op(op: OpCode) -> [u8; 2] { (op as u16).to_le_bytes() }
+
+#[test]
+fn vm_syscall_multi_return_stack_contents() {
+    // Use a real multi-return syscall id with ret_slots = 4: PadGetUp (0x2200)
+    // ROM: SYSCALL 0x2200; HALT
+    let mut rom = Vec::new();
+    rom.extend_from_slice(&enc_op(OpCode::Syscall));
+    rom.extend_from_slice(&0x2200u32.to_le_bytes());
+    rom.extend_from_slice(&enc_op(OpCode::Halt));
+
+    struct TestNative;
+    impl NativeInterface for TestNative {
+        fn syscall(
+            &mut self,
+            id: u32,
+            _args: &[Value],
+            ret: &mut HostReturn,
+            _ctx: &mut HostContext,
+        ) -> Result<(), VmFault> {
+            assert_eq!(id, 0x2200);
+            // Push exactly 4 results in a known order.
+            ret.push_int(11);
+            ret.push_int(22);
+            ret.push_bool(true);
+            ret.push_bounded(7)?;
+            Ok(())
+        }
+    }
+
+    let mut vm = VirtualMachine::new(rom.clone(), vec![]);
+    vm.program.functions = std::sync::Arc::from(vec![FunctionMeta {
+        code_offset: 0,
+        code_len: rom.len() as u32,
+        ..Default::default()
+    }]);
+
+    let mut native = TestNative;
+    let mut ctx = HostContext::new(None);
+    vm.prepare_call("0");
+    let _ = vm.run_budget(100, &mut native, &mut ctx).expect("VM run failed");
+
+    // Verify stack order: last pushed is on top
+    assert_eq!(vm.pop().unwrap(), Value::Bounded(7));
+    assert_eq!(vm.pop().unwrap(), Value::Boolean(true));
+    assert_eq!(vm.pop().unwrap(), Value::Int64(22));
+    assert_eq!(vm.pop().unwrap(), Value::Int64(11));
+    assert!(vm.operand_stack.is_empty());
+}

crates/console/prometeu-vm/tests/verifier_golden.rs

@@ -269,6 +269,35 @@ fn golden_ok_syscall_args_and_returns() {
     assert!(res_b[0] >= 1);
 }
 
+#[test]
+fn golden_ok_syscall_multi_returns() {
+    // Syscall with 0 args and 4 returns: PadGetUp (0x2200)
+    // Program: SYSCALL 0x2200; RET (ret_slots = 4)
+    let mut code = Vec::new();
+    code.extend_from_slice(&enc_op(OpCode::Syscall));
+    code.extend_from_slice(&0x2200u32.to_le_bytes()); // PadGetUp: 0 args, 4 returns
+    code.extend_from_slice(&enc_op(OpCode::Ret));
+
+    let functions = func(FunctionMeta { code_offset: 0, code_len: code.len() as u32, return_slots: 4, ..Default::default() });
+    let res = Verifier::verify(&code, &functions).unwrap();
+    // Max stack height should reach at least 4 due to the syscall's return values
+    assert!(res[0] >= 4);
+}
+
+#[test]
+fn golden_err_syscall_multi_returns_mismatch() {
+    // Same syscall (PadGetUp: returns 4), but function declares only 3 return slots.
+    // Program: SYSCALL 0x2200; RET (ret_slots = 3) → verifier must reject due to BadRetStackHeight.
+    let mut code = Vec::new();
+    code.extend_from_slice(&enc_op(OpCode::Syscall));
+    code.extend_from_slice(&0x2200u32.to_le_bytes());
+    code.extend_from_slice(&enc_op(OpCode::Ret));
+
+    let functions = func(FunctionMeta { code_offset: 0, code_len: code.len() as u32, return_slots: 3, ..Default::default() });
+    let res = Verifier::verify(&code, &functions);
+    assert_eq!(res, Err(VerifierError::BadRetStackHeight { pc: 6, height: 4, expected: 3 }));
+}
+
 #[test]
 fn golden_err_invalid_func_id() {
     // Encode a Call with invalid function id (beyond functions.len())

files/TODOs.md

@@ -1,45 +0,0 @@
-# PR-5.6 — Syscall Multi-Return Tests
-
-### Briefing
-
-We must ensure multi-return syscalls behave correctly with the slot-based ABI.
-
-### Target
-
-* Add deterministic tests covering multi-return behavior.
-
-### Work items
-
-* Create or adapt at least one syscall with `ret_slots > 1`.
-* Add tests:
-
-  * Verify correct stack results after syscall.
-  * Verify incorrect caller expectations fail verification.
-
-### Acceptance checklist
-
-* [ ] Multi-return syscalls behave correctly.
-* [ ] Verifier catches mismatches.
-* [ ] `cargo test` passes.
-
-### Tests
-
-* New multi-return syscall tests.
-
-### Junie instructions
-
-**You MAY:**
-
-* Add deterministic tests.
-* Use existing syscalls or create a simple test-only syscall.
-
-**You MUST NOT:**
-
-* Modify syscall semantics to satisfy tests.
-* Add nondeterministic behavior.
-
-**If unclear:**
-
-* Ask before introducing new test syscalls.
-
-