src/librustc/traits/query/type_op/normalize.rs

   1 use crate::infer::canonical::{Canonicalized, CanonicalizedQueryResponse};
   2 use std::fmt;
   3 use crate::traits::query::Fallible;
   4 use crate::ty::fold::TypeFoldable;
   5 use crate::ty::{self, Lift, ParamEnvAnd, Ty, TyCtxt};
   6
   7 #[derive(Copy, Clone, Debug, Hash, PartialEq, Eq, TypeFoldable, Lift)]
   8 pub struct Normalize<T> {
   9     pub value: T,
  10 }
  11
  12 impl<'tcx, T> Normalize<T>
  13 where
  14     T: fmt::Debug + TypeFoldable<'tcx>,
  15 {
  16     pub fn new(value: T) -> Self {
  17         Self { value }
  18     }
  19 }
  20
  21 impl<'tcx, T> super::QueryTypeOp<'tcx> for Normalize<T>
  22 where
  23     T: Normalizable<'tcx> + 'tcx,
  24 {
  25     type QueryResponse = T;
  26
  27     fn try_fast_path(_tcx: TyCtxt<'tcx>, key: &ParamEnvAnd<'tcx, Self>) -> Option<T> {
  28         if !key.value.value.has_projections() {
  29             Some(key.value.value)
  30         } else {
  31             None
  32         }
  33     }
  34
  35     fn perform_query(
  36         tcx: TyCtxt<'tcx>,
  37         canonicalized: Canonicalized<'tcx, ParamEnvAnd<'tcx, Self>>,
  38     ) -> Fallible<CanonicalizedQueryResponse<'tcx, Self::QueryResponse>> {
  39         T::type_op_method(tcx, canonicalized)
  40     }
  41 }
  42
  43 pub trait Normalizable<'tcx>: fmt::Debug + TypeFoldable<'tcx> + Lift<'tcx> + Copy {
  44     fn type_op_method(
  45         tcx: TyCtxt<'tcx>,
  46         canonicalized: Canonicalized<'tcx, ParamEnvAnd<'tcx, Normalize<Self>>>,
  47     ) -> Fallible<CanonicalizedQueryResponse<'tcx, Self>>;
  48 }
  49
  50 impl Normalizable<'tcx> for Ty<'tcx> {
  51     fn type_op_method(
  52         tcx: TyCtxt<'tcx>,
  53         canonicalized: Canonicalized<'tcx, ParamEnvAnd<'tcx, Normalize<Self>>>,
  54     ) -> Fallible<CanonicalizedQueryResponse<'tcx, Self>> {
  55         tcx.type_op_normalize_ty(canonicalized)
  56     }
  57 }
  58
  59 impl Normalizable<'tcx> for ty::Predicate<'tcx> {
  60     fn type_op_method(
  61         tcx: TyCtxt<'tcx>,
  62         canonicalized: Canonicalized<'tcx, ParamEnvAnd<'tcx, Normalize<Self>>>,
  63     ) -> Fallible<CanonicalizedQueryResponse<'tcx, Self>> {
  64         tcx.type_op_normalize_predicate(canonicalized)
  65     }
  66 }
  67
  68 impl Normalizable<'tcx> for ty::PolyFnSig<'tcx> {
  69     fn type_op_method(
  70         tcx: TyCtxt<'tcx>,
  71         canonicalized: Canonicalized<'tcx, ParamEnvAnd<'tcx, Normalize<Self>>>,
  72     ) -> Fallible<CanonicalizedQueryResponse<'tcx, Self>> {
  73         tcx.type_op_normalize_poly_fn_sig(canonicalized)
  74     }
  75 }
  76
  77 impl Normalizable<'tcx> for ty::FnSig<'tcx> {
  78     fn type_op_method(
  79         tcx: TyCtxt<'tcx>,
  80         canonicalized: Canonicalized<'tcx, ParamEnvAnd<'tcx, Normalize<Self>>>,
  81     ) -> Fallible<CanonicalizedQueryResponse<'tcx, Self>> {
  82         tcx.type_op_normalize_fn_sig(canonicalized)
  83     }
  84 }
  85
  86 impl_stable_hash_for! {
  87     impl<T> for struct Normalize<T> {
  88         value
  89     }
  90 }