src/librustc/ty/query/config.rs

   1 use crate::dep_graph::SerializedDepNodeIndex;
   2 use crate::dep_graph::{DepKind, DepNode};
   3 use crate::ty::query::caches::QueryCache;
   4 use crate::ty::query::plumbing::CycleError;
   5 use crate::ty::query::{Query, QueryState};
   6 use crate::ty::TyCtxt;
   7 use rustc_data_structures::profiling::ProfileCategory;
   8 use rustc_hir::def_id::DefId;
   9
  10 use crate::ich::StableHashingContext;
  11 use rustc_data_structures::fingerprint::Fingerprint;
  12 use std::borrow::Cow;
  13 use std::fmt::Debug;
  14 use std::hash::Hash;
  15
  16 // Query configuration and description traits.
  17
  18 // FIXME(eddyb) false positive, the lifetime parameter is used for `Key`/`Value`.
  19 #[allow(unused_lifetimes)]
  20 pub trait QueryConfig<'tcx> {
  21     const NAME: &'static str;
  22     const CATEGORY: ProfileCategory;
  23
  24     type Key: Eq + Hash + Clone + Debug;
  25     type Value: Clone;
  26 }
  27
  28 pub(crate) trait QueryAccessors<'tcx>: QueryConfig<'tcx> {
  29     const ANON: bool;
  30     const EVAL_ALWAYS: bool;
  31
  32     type Cache: QueryCache<Self::Key, Self::Value>;
  33
  34     fn query(key: Self::Key) -> Query<'tcx>;
  35
  36     // Don't use this method to access query results, instead use the methods on TyCtxt
  37     fn query_state<'a>(tcx: TyCtxt<'tcx>) -> &'a QueryState<'tcx, Self>;
  38
  39     fn to_dep_node(tcx: TyCtxt<'tcx>, key: &Self::Key) -> DepNode;
  40
  41     fn dep_kind() -> DepKind;
  42
  43     // Don't use this method to compute query results, instead use the methods on TyCtxt
  44     fn compute(tcx: TyCtxt<'tcx>, key: Self::Key) -> Self::Value;
  45
  46     fn hash_result(hcx: &mut StableHashingContext<'_>, result: &Self::Value)
  47     -> Option<Fingerprint>;
  48
  49     fn handle_cycle_error(tcx: TyCtxt<'tcx>, error: CycleError<'tcx>) -> Self::Value;
  50 }
  51
  52 pub(crate) trait QueryDescription<'tcx>: QueryAccessors<'tcx> {
  53     fn describe(tcx: TyCtxt<'_>, key: Self::Key) -> Cow<'static, str>;
  54
  55     #[inline]
  56     fn cache_on_disk(_: TyCtxt<'tcx>, _: Self::Key, _: Option<&Self::Value>) -> bool {
  57         false
  58     }
  59
  60     fn try_load_from_disk(_: TyCtxt<'tcx>, _: SerializedDepNodeIndex) -> Option<Self::Value> {
  61         bug!("QueryDescription::load_from_disk() called for an unsupported query.")
  62     }
  63 }
  64
  65 impl<'tcx, M: QueryAccessors<'tcx, Key = DefId>> QueryDescription<'tcx> for M
  66 where
  67     <M as QueryAccessors<'tcx>>::Cache: QueryCache<DefId, <M as QueryConfig<'tcx>>::Value>,
  68 {
  69     default fn describe(tcx: TyCtxt<'_>, def_id: DefId) -> Cow<'static, str> {
  70         if !tcx.sess.verbose() {
  71             format!("processing `{}`", tcx.def_path_str(def_id)).into()
  72         } else {
  73             let name = ::std::any::type_name::<M>();
  74             format!("processing {:?} with query `{}`", def_id, name).into()
  75         }
  76     }
  77
  78     default fn cache_on_disk(_: TyCtxt<'tcx>, _: Self::Key, _: Option<&Self::Value>) -> bool {
  79         false
  80     }
  81
  82     default fn try_load_from_disk(
  83         _: TyCtxt<'tcx>,
  84         _: SerializedDepNodeIndex,
  85     ) -> Option<Self::Value> {
  86         bug!("QueryDescription::load_from_disk() called for an unsupported query.")
  87     }
  88 }