maurice/snix
1
0
Fork 0
Code Issues Pull requests Projects Releases Packages Wiki Activity Actions

refactor(tvix/eval): after calling, the caller has to pop

Browse source 
Previously the various call functions either returned `EvalResult<()>`
or `EvalResult<Value>`, which was confusing.

Now only vm::call_with returns a Value directly, and other parts of
the API just leave the stack top in the post-call state.

This makes it easier to reason about what's going on in non-tail-call
cases (which are making a comeback).

Change-Id: I264ffc683a11aca72dd06e2220a5ff6e7c5fc2b0
Reviewed-on: https://cl.tvl.fyi/c/depot/+/6936
Tested-by: BuildkiteCI
Reviewed-by: grfn <grfn@gws.fyi>
This commit is contained in:
Vincent Ambo 2022-10-11 02:14:47 +03:00 • committed by tazjin
parent 0b04dfe03c
commit 1f84d90811
3 changed files with 29 additions and 21 deletions
Download patch file Download diff file Expand all files Collapse all files

3
tvix/eval/src/value/mod.rs
View file

@ -163,7 +163,8 @@ impl Value {
let call_to_string = |value: &Value, vm: &mut VM| {
// Leave self on the stack as an argument to the function call.
vm.push(self.clone());
let result = vm.call_value(value)?;
vm.call_value(value)?;
let result = vm.pop();
match result {
Value::String(s) => Ok(s),

7
tvix/eval/src/value/thunk.rs
View file

@ -87,10 +87,9 @@ impl Thunk {
std::mem::replace(&mut *thunk_mut, ThunkRepr::Blackhole)
{
drop(thunk_mut);
let evaluated = ThunkRepr::Evaluated(
vm.call(lambda, upvalues, 0)
.map_err(|e| ErrorKind::ThunkForce(Box::new(e)))?,
);
vm.enter_frame(lambda, upvalues, 0)
.map_err(|e| ErrorKind::ThunkForce(Box::new(e)))?;
let evaluated = ThunkRepr::Evaluated(vm.pop());
(*self.0.borrow_mut()) = evaluated;
}
}