move Instance to rustc and use it in the collector

[rust.git] / src / librustc_trans / monomorphize.rs

diff --git a/src/librustc_trans/monomorphize.rs b/src/librustc_trans/monomorphize.rs
index 8f05cc793ef224f73b35f4eed64d3273b706874d..3b746af275a2aed41b471c9ccb160af6109b09c0 100644 (file)
--- a/src/librustc_trans/monomorphize.rs
+++ b/src/librustc_trans/monomorphize.rs
@@ -11,34 +11,35 @@
 use common::*;
 use rustc::hir::def_id::DefId;
 use rustc::infer::TransNormalize;
+use rustc::traits;
 use rustc::ty::fold::{TypeFolder, TypeFoldable};
 use rustc::ty::subst::{Subst, Substs};
 use rustc::ty::{self, Ty, TyCtxt};
-use rustc::util::ppaux;
 use rustc::util::common::MemoizationMap;
-use std::fmt;
 
-#[derive(Copy, Clone, PartialEq, Eq, Hash, Debug)]
-pub struct Instance<'tcx> {
-    pub def: DefId,
-    pub substs: &'tcx Substs<'tcx>,
-}
+use syntax::codemap::DUMMY_SP;
 
-impl<'tcx> fmt::Display for Instance<'tcx> {
-    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
-        ppaux::parameterized(f, &self.substs, self.def, &[])
-    }
-}
+pub use rustc::ty::Instance;
 
-impl<'tcx> Instance<'tcx> {
-    pub fn new(def_id: DefId, substs: &'tcx Substs<'tcx>)
-               -> Instance<'tcx> {
-        assert!(substs.regions().all(|&r| r == ty::ReErased));
-        Instance { def: def_id, substs: substs }
-    }
-    pub fn mono<'a>(scx: &SharedCrateContext<'a, 'tcx>, def_id: DefId) -> Instance<'tcx> {
-        Instance::new(def_id, scx.empty_substs_for_def_id(def_id))
+/// For associated constants from traits, return the impl definition.
+pub fn resolve_const<'a, 'tcx>(
+    scx: &SharedCrateContext<'a, 'tcx>, def_id: DefId, substs: &'tcx Substs<'tcx>
+) -> Instance<'tcx> {
+    if let Some(trait_id) = scx.tcx().trait_of_item(def_id) {
+        let trait_ref = ty::TraitRef::new(trait_id, substs);
+        let trait_ref = ty::Binder(trait_ref);
+        let vtable = fulfill_obligation(scx, DUMMY_SP, trait_ref);
+        if let traits::VtableImpl(vtable_impl) = vtable {
+            let name = scx.tcx().item_name(def_id);
+            let ac = scx.tcx().associated_items(vtable_impl.impl_def_id)
+                .find(|item| item.kind == ty::AssociatedKind::Const && item.name == name);
+            if let Some(ac) = ac {
+                return Instance::new(ac.def_id, vtable_impl.substs);
+            }
+        }
     }
+
+    Instance::new(def_id, substs)
 }
 
 /// Monomorphizes a type from the AST by first applying the in-scope