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 exports;
   6 pub mod map;
   7 pub mod place;
   8
   9 use crate::ich::StableHashingContext;
  10 use crate::ty::query::Providers;
  11 use crate::ty::TyCtxt;
  12 use rustc_data_structures::fingerprint::Fingerprint;
  13 use rustc_data_structures::fx::FxHashMap;
  14 use rustc_data_structures::stable_hasher::{HashStable, StableHasher};
  15 use rustc_hir::def_id::{LocalDefId, LOCAL_CRATE};
  16 use rustc_hir::*;
  17 use rustc_index::vec::IndexVec;
  18
  19 pub struct Owner<'tcx> {
  20     parent: HirId,
  21     node: Node<'tcx>,
  22 }
  23
  24 impl<'a, 'tcx> HashStable<StableHashingContext<'a>> for Owner<'tcx> {
  25     fn hash_stable(&self, hcx: &mut StableHashingContext<'a>, hasher: &mut StableHasher) {
  26         let Owner { parent, node } = self;
  27         hcx.while_hashing_hir_bodies(false, |hcx| {
  28             parent.hash_stable(hcx, hasher);
  29             node.hash_stable(hcx, hasher);
  30         });
  31     }
  32 }
  33
  34 #[derive(Clone)]
  35 pub struct ParentedNode<'tcx> {
  36     parent: ItemLocalId,
  37     node: Node<'tcx>,
  38 }
  39
  40 pub struct OwnerNodes<'tcx> {
  41     hash: Fingerprint,
  42     nodes: IndexVec<ItemLocalId, Option<ParentedNode<'tcx>>>,
  43     bodies: FxHashMap<ItemLocalId, &'tcx Body<'tcx>>,
  44 }
  45
  46 impl<'a, 'tcx> HashStable<StableHashingContext<'a>> for OwnerNodes<'tcx> {
  47     fn hash_stable(&self, hcx: &mut StableHashingContext<'a>, hasher: &mut StableHasher) {
  48         // We ignore the `nodes` and `bodies` fields since these refer to information included in
  49         // `hash` which is hashed in the collector and used for the crate hash.
  50         let OwnerNodes { hash, nodes: _, bodies: _ } = *self;
  51         hash.hash_stable(hcx, hasher);
  52     }
  53 }
  54
  55 impl<'tcx> TyCtxt<'tcx> {
  56     #[inline(always)]
  57     pub fn hir(self) -> map::Map<'tcx> {
  58         map::Map { tcx: self }
  59     }
  60
  61     pub fn parent_module(self, id: HirId) -> LocalDefId {
  62         self.parent_module_from_def_id(id.owner)
  63     }
  64 }
  65
  66 pub fn provide(providers: &mut Providers) {
  67     providers.parent_module_from_def_id = |tcx, id| {
  68         let hir = tcx.hir();
  69         hir.local_def_id(hir.get_module_parent_node(hir.local_def_id_to_hir_id(id)))
  70     };
  71     providers.hir_crate = |tcx, _| tcx.untracked_crate;
  72     providers.index_hir = map::index_hir;
  73     providers.hir_module_items = |tcx, id| {
  74         let hir = tcx.hir();
  75         let module = hir.local_def_id_to_hir_id(id);
  76         &tcx.untracked_crate.modules[&module]
  77     };
  78     providers.hir_owner = |tcx, id| tcx.index_hir(LOCAL_CRATE).map[id].signature;
  79     providers.hir_owner_nodes = |tcx, id| tcx.index_hir(LOCAL_CRATE).map[id].with_bodies.as_deref();
  80     providers.fn_arg_names = |tcx, id| {
  81         let hir = tcx.hir();
  82         let hir_id = hir.local_def_id_to_hir_id(id.expect_local());
  83         if let Some(body_id) = hir.maybe_body_owned_by(hir_id) {
  84             tcx.arena.alloc_from_iter(hir.body_param_names(body_id))
  85         } else if let Node::TraitItem(&TraitItem {
  86             kind: TraitItemKind::Fn(_, TraitFn::Required(idents)),
  87             ..
  88         }) = hir.get(hir_id)
  89         {
  90             tcx.arena.alloc_slice(idents)
  91         } else {
  92             span_bug!(hir.span(hir_id), "fn_arg_names: unexpected item {:?}", id);
  93         }
  94     };
  95     map::provide(providers);
  96 }