compiler/rustc_middle/src/hir/mod.rs

   1 //! HIR datatypes. See the [rustc dev guide] for more info.
   2 //!
   3 //! [rustc dev guide]: https://rustc-dev-guide.rust-lang.org/hir.html
   4
   5 pub mod map;
   6 pub mod nested_filter;
   7 pub mod place;
   8
   9 use crate::ty::query::Providers;
  10 use crate::ty::{DefIdTree, ImplSubject, TyCtxt};
  11 use rustc_data_structures::fingerprint::Fingerprint;
  12 use rustc_data_structures::stable_hasher::{HashStable, StableHasher};
  13 use rustc_data_structures::sync::{par_for_each_in, Send, Sync};
  14 use rustc_hir::def_id::{DefId, LocalDefId};
  15 use rustc_hir::*;
  16 use rustc_query_system::ich::StableHashingContext;
  17 use rustc_span::{ExpnId, DUMMY_SP};
  18
  19 /// Top-level HIR node for current owner. This only contains the node for which
  20 /// `HirId::local_id == 0`, and excludes bodies.
  21 ///
  22 /// This struct exists to encapsulate all access to the hir_owner query in this module, and to
  23 /// implement HashStable without hashing bodies.
  24 #[derive(Copy, Clone, Debug)]
  25 pub struct Owner<'tcx> {
  26     node: OwnerNode<'tcx>,
  27     hash_without_bodies: Fingerprint,
  28 }
  29
  30 impl<'a, 'tcx> HashStable<StableHashingContext<'a>> for Owner<'tcx> {
  31     #[inline]
  32     fn hash_stable(&self, hcx: &mut StableHashingContext<'a>, hasher: &mut StableHasher) {
  33         let Owner { node: _, hash_without_bodies } = self;
  34         hash_without_bodies.hash_stable(hcx, hasher)
  35     }
  36 }
  37
  38 /// Gather the LocalDefId for each item-like within a module, including items contained within
  39 /// bodies.  The Ids are in visitor order.  This is used to partition a pass between modules.
  40 #[derive(Debug, HashStable, Encodable, Decodable)]
  41 pub struct ModuleItems {
  42     submodules: Box<[LocalDefId]>,
  43     items: Box<[ItemId]>,
  44     trait_items: Box<[TraitItemId]>,
  45     impl_items: Box<[ImplItemId]>,
  46     foreign_items: Box<[ForeignItemId]>,
  47     body_owners: Box<[LocalDefId]>,
  48 }
  49
  50 impl ModuleItems {
  51     pub fn items(&self) -> impl Iterator<Item = ItemId> + '_ {
  52         self.items.iter().copied()
  53     }
  54
  55     pub fn trait_items(&self) -> impl Iterator<Item = TraitItemId> + '_ {
  56         self.trait_items.iter().copied()
  57     }
  58
  59     pub fn impl_items(&self) -> impl Iterator<Item = ImplItemId> + '_ {
  60         self.impl_items.iter().copied()
  61     }
  62
  63     pub fn foreign_items(&self) -> impl Iterator<Item = ForeignItemId> + '_ {
  64         self.foreign_items.iter().copied()
  65     }
  66
  67     pub fn definitions(&self) -> impl Iterator<Item = LocalDefId> + '_ {
  68         self.items
  69             .iter()
  70             .map(|id| id.def_id)
  71             .chain(self.trait_items.iter().map(|id| id.def_id))
  72             .chain(self.impl_items.iter().map(|id| id.def_id))
  73             .chain(self.foreign_items.iter().map(|id| id.def_id))
  74     }
  75
  76     pub fn par_items(&self, f: impl Fn(ItemId) + Send + Sync) {
  77         par_for_each_in(&self.items[..], |&id| f(id))
  78     }
  79
  80     pub fn par_trait_items(&self, f: impl Fn(TraitItemId) + Send + Sync) {
  81         par_for_each_in(&self.trait_items[..], |&id| f(id))
  82     }
  83
  84     pub fn par_impl_items(&self, f: impl Fn(ImplItemId) + Send + Sync) {
  85         par_for_each_in(&self.impl_items[..], |&id| f(id))
  86     }
  87
  88     pub fn par_foreign_items(&self, f: impl Fn(ForeignItemId) + Send + Sync) {
  89         par_for_each_in(&self.foreign_items[..], |&id| f(id))
  90     }
  91 }
  92
  93 impl<'tcx> TyCtxt<'tcx> {
  94     #[inline(always)]
  95     pub fn hir(self) -> map::Map<'tcx> {
  96         map::Map { tcx: self }
  97     }
  98
  99     pub fn parent_module(self, id: HirId) -> LocalDefId {
 100         self.parent_module_from_def_id(id.owner)
 101     }
 102
 103     pub fn impl_subject(self, def_id: DefId) -> ImplSubject<'tcx> {
 104         self.impl_trait_ref(def_id)
 105             .map(ImplSubject::Trait)
 106             .unwrap_or_else(|| ImplSubject::Inherent(self.type_of(def_id)))
 107     }
 108 }
 109
 110 pub fn provide(providers: &mut Providers) {
 111     providers.parent_module_from_def_id = |tcx, id| {
 112         let hir = tcx.hir();
 113         hir.get_module_parent_node(hir.local_def_id_to_hir_id(id))
 114     };
 115     providers.hir_crate_items = map::hir_crate_items;
 116     providers.crate_hash = map::crate_hash;
 117     providers.hir_module_items = map::hir_module_items;
 118     providers.hir_owner = |tcx, id| {
 119         let owner = tcx.hir_crate(()).owners.get(id)?.as_owner()?;
 120         let node = owner.node();
 121         Some(Owner { node, hash_without_bodies: owner.nodes.hash_without_bodies })
 122     };
 123     providers.local_def_id_to_hir_id = |tcx, id| {
 124         let owner = tcx.hir_crate(()).owners[id].map(|_| ());
 125         match owner {
 126             MaybeOwner::Owner(_) => HirId::make_owner(id),
 127             MaybeOwner::Phantom => bug!("No HirId for {:?}", id),
 128             MaybeOwner::NonOwner(hir_id) => hir_id,
 129         }
 130     };
 131     providers.hir_owner_nodes = |tcx, id| tcx.hir_crate(()).owners[id].map(|i| &i.nodes);
 132     providers.hir_owner_parent = |tcx, id| {
 133         // Accessing the local_parent is ok since its value is hashed as part of `id`'s DefPathHash.
 134         tcx.opt_local_parent(id).map_or(CRATE_HIR_ID, |parent| {
 135             let mut parent_hir_id = tcx.hir().local_def_id_to_hir_id(parent);
 136             if let Some(local_id) =
 137                 tcx.hir_crate(()).owners[parent_hir_id.owner].unwrap().parenting.get(&id)
 138             {
 139                 parent_hir_id.local_id = *local_id;
 140             }
 141             parent_hir_id
 142         })
 143     };
 144     providers.hir_attrs =
 145         |tcx, id| tcx.hir_crate(()).owners[id].as_owner().map_or(AttributeMap::EMPTY, |o| &o.attrs);
 146     providers.source_span =
 147         |tcx, def_id| tcx.resolutions(()).source_span.get(def_id).copied().unwrap_or(DUMMY_SP);
 148     providers.def_span = |tcx, def_id| {
 149         let def_id = def_id.expect_local();
 150         let hir_id = tcx.hir().local_def_id_to_hir_id(def_id);
 151         tcx.hir().opt_span(hir_id).unwrap_or(DUMMY_SP)
 152     };
 153     providers.def_ident_span = |tcx, def_id| {
 154         let def_id = def_id.expect_local();
 155         let hir_id = tcx.hir().local_def_id_to_hir_id(def_id);
 156         tcx.hir().opt_ident_span(hir_id)
 157     };
 158     providers.fn_arg_names = |tcx, id| {
 159         let hir = tcx.hir();
 160         let def_id = id.expect_local();
 161         let hir_id = hir.local_def_id_to_hir_id(def_id);
 162         if let Some(body_id) = hir.maybe_body_owned_by(def_id) {
 163             tcx.arena.alloc_from_iter(hir.body_param_names(body_id))
 164         } else if let Node::TraitItem(&TraitItem {
 165             kind: TraitItemKind::Fn(_, TraitFn::Required(idents)),
 166             ..
 167         }) = hir.get(hir_id)
 168         {
 169             tcx.arena.alloc_slice(idents)
 170         } else {
 171             span_bug!(hir.span(hir_id), "fn_arg_names: unexpected item {:?}", id);
 172         }
 173     };
 174     providers.opt_def_kind = |tcx, def_id| tcx.hir().opt_def_kind(def_id.expect_local());
 175     providers.all_local_trait_impls = |tcx, ()| &tcx.resolutions(()).trait_impls;
 176     providers.expn_that_defined = |tcx, id| {
 177         let id = id.expect_local();
 178         tcx.resolutions(()).expn_that_defined.get(&id).copied().unwrap_or(ExpnId::root())
 179     };
 180     providers.in_scope_traits_map =
 181         |tcx, id| tcx.hir_crate(()).owners[id].as_owner().map(|owner_info| &owner_info.trait_map);
 182 }