Skip to content

Add vtable signature for closure #8

New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Merged
Nadrieril merged 3 commits into from
Dec 2, 2025
Merged

Add vtable signature for closure #8

Changes from all commits
Commits
Show all changes
3 commits
Select commit Hold shift + click to select a range
962180b
add vtable_sig for closure
Sam-Ni Dec 1, 2025
ad607bc
Merge branch 'main' of github.com:AeneasVerif/hax into closure-vtable…
Sam-Ni Dec 2, 2025
84a46cc
add real sig for closure
Sam-Ni Dec 2, 2025
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
58 changes: 58 additions & 0 deletions frontend/exporter/src/types/new/full_def.rs
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -410,6 +410,15 @@ pub enum FullDefKind<Body> {
drop_glue: Option<Body>,
/// Info required to construct a virtual `Drop` impl for this closure.
destruct_impl: Box<VirtualTraitImpl>,
/// The function signature when this closure is used as `FnMut` (or `Fn`) in a vtable.
/// `None` if this closure does not support `FnMut` or `Fn`.
/// `Some(sig)` if this closure implements `FnMut` (or `Fn`),
/// where `sig` is the trait method declaration's signature with `Self`
/// replaced by `dyn Trait` and associated types normalized (same as vtable_sig in `AssocFn`).
fn_mut_vtable_sig: Option<PolyFnSig>,
fn_vtable_sig: Option<PolyFnSig>,
fn_mut_sig: Option<PolyFnSig>,
fn_sig: Option<PolyFnSig>,
},

// Constants
Expand Down Expand Up @@ -554,6 +563,43 @@ fn gen_vtable_sig<'tcx>(
Some(normalized_sig.sinto(s))
}

#[cfg(feature = "rustc")]
fn gen_closure_sig<'tcx>(
// The state that owns the method DefId
s: &impl UnderOwnerState<'tcx>,
// The `Fn` or `FnMut` trait reference of the closure
fn_or_fn_mut_ref: Option<ty::TraitRef<'tcx>>,
// whether construct a vtable_sig or a real_sig
is_vtable: bool,
) -> Option<PolyFnSig> {
let fn_or_fn_mut_ref = fn_or_fn_mut_ref?;
let tcx = s.base().tcx;

// Get AssocItems of `Fn` or `FnMut`
let assoc_item = tcx.associated_items(fn_or_fn_mut_ref.def_id);
// Pick `call` or `call_mut`
let call_method = assoc_item.in_definition_order().
next().map(|elem| elem).unwrap();
// Get its signature
let fn_decl_sig = tcx.fn_sig(call_method.def_id);
let trait_args = if is_vtable {
// Generate type of shim receiver
let dyn_self = dyn_self_ty(tcx, s.typing_env(), fn_or_fn_mut_ref).unwrap();
// Construct signature with dyn_self
let mut full_args = vec![ty::GenericArg::from(dyn_self)];
full_args.extend(fn_or_fn_mut_ref.args[1..].iter());
tcx.mk_args(&full_args)
} else {
fn_or_fn_mut_ref.args
};

// Instantiate and normalize the signature.
let method_decl_sig = fn_decl_sig.instantiate(tcx, trait_args);
let normalized_sig = normalize(tcx, s.typing_env(), method_decl_sig);

Some(normalized_sig.sinto(s))
}

#[cfg(feature = "rustc")]
/// Construct the `FullDefKind` for this item.
///
Expand Down Expand Up @@ -822,6 +868,14 @@ where
let fn_mut_trait = tcx.lang_items().fn_mut_trait().unwrap();
let fn_trait = tcx.lang_items().fn_trait().unwrap();
let destruct_trait = tcx.lang_items().destruct_trait().unwrap();

let fn_mut_ref = matches!(closure.kind(), FnMut | Fn)
.then(|| ty::TraitRef::new(tcx, fn_mut_trait, trait_args));

let fn_ref = matches!(closure.kind(), Fn)
.then(|| ty::TraitRef::new(tcx, fn_trait, trait_args));


FullDefKind::Closure {
param_env: get_param_env(s, args),
is_const: tcx.constness(def_id) == rustc_hir::Constness::Const,
Expand All @@ -840,6 +894,10 @@ where
.then(|| virtual_impl_for(s, ty::TraitRef::new(tcx, fn_mut_trait, trait_args))),
fn_impl: matches!(closure.kind(), Fn)
.then(|| virtual_impl_for(s, ty::TraitRef::new(tcx, fn_trait, trait_args))),
fn_mut_vtable_sig: gen_closure_sig(s, fn_mut_ref, true),
fn_vtable_sig: gen_closure_sig(s, fn_ref, true),
fn_mut_sig: gen_closure_sig(s, fn_mut_ref, false),
fn_sig: gen_closure_sig(s, fn_ref, false),
}
}
kind @ (RDefKind::Const { .. }
Expand Down