move impl documentation to their actual locations

This commit is contained in:
Deadbeef 2024-03-14 20:18:04 +08:00
parent 4b76fac302
commit 69d781abef
3 changed files with 12 additions and 34 deletions

View File

@ -121,7 +121,6 @@ pub fn unadjusted_abi_align(self) -> Align {
///
/// Currently, that means that the type is pointer-sized, pointer-aligned,
/// and has a initialized (non-union), scalar ABI.
// Please also update compiler/rustc_trait_selection/src/solve/trait_goals.rs if the criteria changes
pub fn is_pointer_like(self, data_layout: &TargetDataLayout) -> bool {
self.size() == data_layout.pointer_size
&& self.align().abi == data_layout.pointer_align.abi

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@ -120,6 +120,8 @@ pub(in crate::solve) fn instantiate_constituent_tys_for_sized_trait<'tcx>(
ty: Ty<'tcx>,
) -> Result<Vec<ty::Binder<'tcx, Ty<'tcx>>>, NoSolution> {
match *ty.kind() {
// impl Sized for u*, i*, bool, f*, FnDef, FnPtr, *(const/mut) T, char, &mut? T, [T; N], dyn* Trait, !
// impl Sized for Coroutine, CoroutineWitness, Closure, CoroutineClosure
ty::Infer(ty::IntVar(_) | ty::FloatVar(_))
| ty::Uint(_)
| ty::Int(_)
@ -152,8 +154,10 @@ pub(in crate::solve) fn instantiate_constituent_tys_for_sized_trait<'tcx>(
bug!("unexpected type `{ty}`")
}
// impl Sized for (T1, T2, .., Tn) where T1: Sized, T2: Sized, .. Tn: Sized
ty::Tuple(tys) => Ok(tys.iter().map(ty::Binder::dummy).collect()),
// impl Sized for Adt where T: Sized forall T in field types
ty::Adt(def, args) => {
let sized_crit = def.sized_constraint(ecx.tcx());
Ok(sized_crit.iter_instantiated(ecx.tcx(), args).map(ty::Binder::dummy).collect())
@ -167,6 +171,7 @@ pub(in crate::solve) fn instantiate_constituent_tys_for_copy_clone_trait<'tcx>(
ty: Ty<'tcx>,
) -> Result<Vec<ty::Binder<'tcx, Ty<'tcx>>>, NoSolution> {
match *ty.kind() {
// impl Copy/Clone for FnDef, FnPtr
ty::FnDef(..) | ty::FnPtr(_) | ty::Error(_) => Ok(vec![]),
// Implementations are provided in core
@ -196,12 +201,16 @@ pub(in crate::solve) fn instantiate_constituent_tys_for_copy_clone_trait<'tcx>(
bug!("unexpected type `{ty}`")
}
// impl Copy/Clone for (T1, T2, .., Tn) where T1: Copy/Clone, T2: Copy/Clone, .. Tn: Copy/Clone
ty::Tuple(tys) => Ok(tys.iter().map(ty::Binder::dummy).collect()),
// impl Copy/Clone for Closure where Self::TupledUpvars: Copy/Clone
ty::Closure(_, args) => Ok(vec![ty::Binder::dummy(args.as_closure().tupled_upvars_ty())]),
ty::CoroutineClosure(..) => Err(NoSolution),
// only when `coroutine_clone` is enabled and the coroutine is movable
// impl Copy/Clone for Coroutine where T: Copy/Clone forall T in (upvars, witnesses)
ty::Coroutine(def_id, args) => match ecx.tcx().coroutine_movability(def_id) {
Movability::Static => Err(NoSolution),
Movability::Movable => {
@ -217,6 +226,7 @@ pub(in crate::solve) fn instantiate_constituent_tys_for_copy_clone_trait<'tcx>(
}
},
// impl Copy/Clone for CoroutineWitness where T: Copy/Clone forall T in coroutine_hidden_types
ty::CoroutineWitness(def_id, args) => Ok(ecx
.tcx()
.coroutine_hidden_types(def_id)

View File

@ -188,16 +188,6 @@ fn consider_trait_alias_candidate(
})
}
/// ```rust,ignore (not valid rust syntax)
/// impl Sized for u*, i*, bool, f*, FnPtr, FnDef, *(const/mut) T, char, &mut? T, [T; N], dyn* Trait, !
///
/// impl Sized for (T1, T2, .., Tn) where T1: Sized, T2: Sized, .. Tn: Sized
///
/// impl Sized for Adt where T: Sized forall T in field types
/// ```
///
/// note that `[T; N]` is unconditionally sized since `T: Sized` is required for the array type to be
/// well-formed.
fn consider_builtin_sized_candidate(
ecx: &mut EvalCtxt<'_, 'tcx>,
goal: Goal<'tcx, Self>,
@ -212,20 +202,6 @@ fn consider_builtin_sized_candidate(
)
}
/// ```rust,ignore (not valid rust syntax)
/// impl Copy/Clone for FnDef, FnPtr
///
/// impl Copy/Clone for (T1, T2, .., Tn) where T1: Copy/Clone, T2: Copy/Clone, .. Tn: Copy/Clone
///
/// impl Copy/Clone for Closure where T: Copy/Clone forall T in upvars
///
/// // only when `coroutine_clone` is enabled and the coroutine is movable
/// impl Copy/Clone for Coroutine where T: Copy/Clone forall T in (upvars, witnesses)
///
/// impl Copy/Clone for CoroutineWitness where T: Copy/Clone forall T in coroutine_hidden_types
/// ```
///
/// Some built-in types don't have built-in impls because they can be implemented within the standard library.
fn consider_builtin_copy_clone_candidate(
ecx: &mut EvalCtxt<'_, 'tcx>,
goal: Goal<'tcx, Self>,
@ -240,9 +216,6 @@ fn consider_builtin_copy_clone_candidate(
)
}
/// Implements `PointerLike` for types that are pointer-sized, pointer-aligned,
/// and have a initialized (non-union), scalar ABI.
// Please also update compiler/rustc_target/src/abi/mod.rs if the criteria changes
fn consider_builtin_pointer_like_candidate(
ecx: &mut EvalCtxt<'_, 'tcx>,
goal: Goal<'tcx, Self>,
@ -272,18 +245,13 @@ fn consider_builtin_pointer_like_candidate(
}
}
/// ```rust,ignore (not valid rust syntax)
/// impl FnPtr for FnPtr {}
/// impl !FnPtr for T where T != FnPtr && T is rigid {}
/// ```
///
/// Note: see [`Ty::is_known_rigid`] for what it means for the type to be rigid.
fn consider_builtin_fn_ptr_trait_candidate(
ecx: &mut EvalCtxt<'_, 'tcx>,
goal: Goal<'tcx, Self>,
) -> QueryResult<'tcx> {
let self_ty = goal.predicate.self_ty();
match goal.predicate.polarity {
// impl FnPtr for FnPtr {}
ty::ImplPolarity::Positive => {
if self_ty.is_fn_ptr() {
ecx.evaluate_added_goals_and_make_canonical_response(Certainty::Yes)
@ -291,6 +259,7 @@ fn consider_builtin_fn_ptr_trait_candidate(
Err(NoSolution)
}
}
// impl !FnPtr for T where T != FnPtr && T is rigid {}
ty::ImplPolarity::Negative => {
// If a type is rigid and not a fn ptr, then we know for certain
// that it does *not* implement `FnPtr`.