compiler/rustc_monomorphize/src/lib.rs

   1 #![feature(array_windows)]
   2 #![feature(bool_to_option)]
   3 #![feature(crate_visibility_modifier)]
   4 #![feature(control_flow_enum)]
   5 #![feature(let_else)]
   6 #![recursion_limit = "256"]
   7 #![cfg_attr(not(bootstrap), allow(rustc::potential_query_instability))]
   8
   9 #[macro_use]
  10 extern crate tracing;
  11 #[macro_use]
  12 extern crate rustc_middle;
  13
  14 use rustc_hir::lang_items::LangItem;
  15 use rustc_middle::traits;
  16 use rustc_middle::ty::adjustment::CustomCoerceUnsized;
  17 use rustc_middle::ty::query::Providers;
  18 use rustc_middle::ty::{self, Ty, TyCtxt};
  19
  20 mod collector;
  21 mod partitioning;
  22 mod polymorphize;
  23 mod util;
  24
  25 fn custom_coerce_unsize_info<'tcx>(
  26     tcx: TyCtxt<'tcx>,
  27     source_ty: Ty<'tcx>,
  28     target_ty: Ty<'tcx>,
  29 ) -> CustomCoerceUnsized {
  30     let def_id = tcx.require_lang_item(LangItem::CoerceUnsized, None);
  31
  32     let trait_ref = ty::Binder::dummy(ty::TraitRef {
  33         def_id,
  34         substs: tcx.mk_substs_trait(source_ty, &[target_ty.into()]),
  35     });
  36
  37     match tcx.codegen_fulfill_obligation((ty::ParamEnv::reveal_all(), trait_ref)) {
  38         Ok(traits::ImplSource::UserDefined(traits::ImplSourceUserDefinedData {
  39             impl_def_id,
  40             ..
  41         })) => tcx.coerce_unsized_info(impl_def_id).custom_kind.unwrap(),
  42         impl_source => {
  43             bug!("invalid `CoerceUnsized` impl_source: {:?}", impl_source);
  44         }
  45     }
  46 }
  47
  48 pub fn provide(providers: &mut Providers) {
  49     partitioning::provide(providers);
  50     polymorphize::provide(providers);
  51 }