compiler/rustc_query_system/src/query/config.rs

   1 //! Query configuration and description traits.
   2
   3 use crate::dep_graph::DepNode;
   4 use crate::dep_graph::SerializedDepNodeIndex;
   5 use crate::error::HandleCycleError;
   6 use crate::ich::StableHashingContext;
   7 use crate::query::caches::QueryCache;
   8 use crate::query::{QueryContext, QueryState};
   9
  10 use rustc_data_structures::fingerprint::Fingerprint;
  11 use std::fmt::Debug;
  12 use std::hash::Hash;
  13
  14 pub trait QueryConfig {
  15     const NAME: &'static str;
  16
  17     type Key: Eq + Hash + Clone + Debug;
  18     type Value;
  19     type Stored: Clone;
  20 }
  21
  22 #[derive(Copy, Clone)]
  23 pub struct QueryVTable<CTX: QueryContext, K, V> {
  24     pub anon: bool,
  25     pub dep_kind: CTX::DepKind,
  26     pub eval_always: bool,
  27     pub depth_limit: bool,
  28
  29     pub compute: fn(CTX::DepContext, K) -> V,
  30     pub hash_result: Option<fn(&mut StableHashingContext<'_>, &V) -> Fingerprint>,
  31     pub handle_cycle_error: HandleCycleError,
  32     // NOTE: this is also `None` if `cache_on_disk()` returns false, not just if it's unsupported by the query
  33     pub try_load_from_disk: Option<fn(CTX, SerializedDepNodeIndex) -> Option<V>>,
  34 }
  35
  36 impl<CTX: QueryContext, K, V> QueryVTable<CTX, K, V> {
  37     pub(crate) fn to_dep_node(&self, tcx: CTX::DepContext, key: &K) -> DepNode<CTX::DepKind>
  38     where
  39         K: crate::dep_graph::DepNodeParams<CTX::DepContext>,
  40     {
  41         DepNode::construct(tcx, self.dep_kind, key)
  42     }
  43
  44     pub(crate) fn compute(&self, tcx: CTX::DepContext, key: K) -> V {
  45         (self.compute)(tcx, key)
  46     }
  47 }
  48
  49 pub trait QueryDescription<CTX: QueryContext>: QueryConfig {
  50     type Cache: QueryCache<Key = Self::Key, Stored = Self::Stored, Value = Self::Value>;
  51
  52     fn describe(tcx: CTX, key: Self::Key) -> String;
  53
  54     // Don't use this method to access query results, instead use the methods on TyCtxt
  55     fn query_state<'a>(tcx: CTX) -> &'a QueryState<Self::Key>
  56     where
  57         CTX: 'a;
  58
  59     // Don't use this method to access query results, instead use the methods on TyCtxt
  60     fn query_cache<'a>(tcx: CTX) -> &'a Self::Cache
  61     where
  62         CTX: 'a;
  63
  64     // Don't use this method to compute query results, instead use the methods on TyCtxt
  65     fn make_vtable(tcx: CTX, key: &Self::Key) -> QueryVTable<CTX, Self::Key, Self::Value>;
  66
  67     fn cache_on_disk(tcx: CTX::DepContext, key: &Self::Key) -> bool;
  68
  69     // Don't use this method to compute query results, instead use the methods on TyCtxt
  70     fn execute_query(tcx: CTX::DepContext, k: Self::Key) -> Self::Stored;
  71 }