From 1a87fc2635660bbf2947c17901dbd7dec75a63cb Mon Sep 17 00:00:00 2001
From: Niko Matsakis <niko@alum.mit.edu>
Date: Fri, 17 Mar 2017 16:17:45 -0400
Subject: [PATCH 1/3] convert `custom_coerce_unsized_kind` into a
`coerce_unsized_info`
This "on-demand" task both checks for errors and computes the custom
unsized kind, if any. This task is only defined on impls of
`CoerceUnsized`; invoking it on any other kind of impl results in a bug.
This is just to avoid having an `Option`, could easily be changed.
---
src/librustc/ty/adjustment.rs | 15 ++++++++
src/librustc/ty/maps.rs | 4 +--
src/librustc/ty/mod.rs | 4 +--
src/librustc_metadata/cstore_impl.rs | 6 ++--
src/librustc_metadata/decoder.rs | 8 ++---
src/librustc_metadata/encoder.rs | 18 +++++++---
src/librustc_metadata/schema.rs | 4 ++-
src/librustc_trans/monomorphize.rs | 2 +-
src/librustc_typeck/coherence/builtin.rs | 46 ++++++++++++++++--------
src/librustc_typeck/coherence/mod.rs | 3 ++
10 files changed, 77 insertions(+), 33 deletions(-)
diff --git a/src/librustc/ty/adjustment.rs b/src/librustc/ty/adjustment.rs
index 34977822bc69d..d8ca30477205c 100644
--- a/src/librustc/ty/adjustment.rs
+++ b/src/librustc/ty/adjustment.rs
@@ -139,6 +139,21 @@ pub enum AutoBorrow<'tcx> {
RawPtr(hir::Mutability),
}
+/// Information for `CoerceUnsized` impls, storing information we
+/// have computed about the coercion.
+///
+/// This struct can be obtained via the `coerce_impl_info` query.
+/// Demanding this struct also has the side-effect of reporting errors
+/// for inappropriate impls.
+#[derive(Clone, Copy, RustcEncodable, RustcDecodable, Debug)]
+pub struct CoerceUnsizedInfo {
+ /// If this is a "custom coerce" impl, then what kind of custom
+ /// coercion is it? This applies to impls of `CoerceUnsized` for
+ /// structs, primarily, where we store a bit of info about which
+ /// fields need to be coerced.
+ pub custom_kind: Option<CustomCoerceUnsized>
+}
+
#[derive(Clone, Copy, RustcEncodable, RustcDecodable, Debug)]
pub enum CustomCoerceUnsized {
/// Records the index of the field being coerced.
diff --git a/src/librustc/ty/maps.rs b/src/librustc/ty/maps.rs
index ac8c38c7d5856..d4214dc429ced 100644
--- a/src/librustc/ty/maps.rs
+++ b/src/librustc/ty/maps.rs
@@ -393,8 +393,8 @@ define_maps! { <'tcx>
pub closure_type: ItemSignature(DefId) -> ty::PolyFnSig<'tcx>,
/// Caches CoerceUnsized kinds for impls on custom types.
- pub custom_coerce_unsized_kind: ItemSignature(DefId)
- -> ty::adjustment::CustomCoerceUnsized,
+ pub coerce_unsized_info: ItemSignature(DefId)
+ -> ty::adjustment::CoerceUnsizedInfo,
pub typeck_tables: TypeckTables(DefId) -> &'tcx ty::TypeckTables<'tcx>,
diff --git a/src/librustc/ty/mod.rs b/src/librustc/ty/mod.rs
index 36d1ae74e9114..d140426995812 100644
--- a/src/librustc/ty/mod.rs
+++ b/src/librustc/ty/mod.rs
@@ -2054,8 +2054,8 @@ impl<'a, 'gcx, 'tcx> TyCtxt<'a, 'gcx, 'tcx> {
})
}
- pub fn custom_coerce_unsized_kind(self, did: DefId) -> adjustment::CustomCoerceUnsized {
- queries::custom_coerce_unsized_kind::get(self, DUMMY_SP, did)
+ pub fn coerce_unsized_info(self, did: DefId) -> adjustment::CoerceUnsizedInfo {
+ queries::coerce_unsized_info::get(self, DUMMY_SP, did)
}
pub fn associated_item(self, def_id: DefId) -> AssociatedItem {
diff --git a/src/librustc_metadata/cstore_impl.rs b/src/librustc_metadata/cstore_impl.rs
index 2a67b79eaa52e..7cac201f14f76 100644
--- a/src/librustc_metadata/cstore_impl.rs
+++ b/src/librustc_metadata/cstore_impl.rs
@@ -88,9 +88,9 @@ provide! { <'tcx> tcx, def_id, cdata
}
associated_item => { cdata.get_associated_item(def_id.index) }
impl_trait_ref => { cdata.get_impl_trait(def_id.index, tcx) }
- custom_coerce_unsized_kind => {
- cdata.get_custom_coerce_unsized_kind(def_id.index).unwrap_or_else(|| {
- bug!("custom_coerce_unsized_kind: `{:?}` is missing its kind", def_id);
+ coerce_unsized_info => {
+ cdata.get_coerce_unsized_info(def_id.index).unwrap_or_else(|| {
+ bug!("coerce_unsized_info: `{:?}` is missing its info", def_id);
})
}
mir => {
diff --git a/src/librustc_metadata/decoder.rs b/src/librustc_metadata/decoder.rs
index 6ccdf8092f210..3de1e3442c69d 100644
--- a/src/librustc_metadata/decoder.rs
+++ b/src/librustc_metadata/decoder.rs
@@ -643,10 +643,10 @@ impl<'a, 'tcx> CrateMetadata {
self.get_impl_data(id).polarity
}
- pub fn get_custom_coerce_unsized_kind(&self,
- id: DefIndex)
- -> Option<ty::adjustment::CustomCoerceUnsized> {
- self.get_impl_data(id).coerce_unsized_kind
+ pub fn get_coerce_unsized_info(&self,
+ id: DefIndex)
+ -> Option<ty::adjustment::CoerceUnsizedInfo> {
+ self.get_impl_data(id).coerce_unsized_info
}
pub fn get_impl_trait(&self,
diff --git a/src/librustc_metadata/encoder.rs b/src/librustc_metadata/encoder.rs
index 044ed529ef74c..5bc84759f8797 100644
--- a/src/librustc_metadata/encoder.rs
+++ b/src/librustc_metadata/encoder.rs
@@ -695,7 +695,7 @@ impl<'a, 'tcx> EncodeContext<'a, 'tcx> {
let data = ImplData {
polarity: hir::ImplPolarity::Positive,
parent_impl: None,
- coerce_unsized_kind: None,
+ coerce_unsized_info: None,
trait_ref: tcx.impl_trait_ref(def_id).map(|trait_ref| self.lazy(&trait_ref)),
};
@@ -715,13 +715,21 @@ impl<'a, 'tcx> EncodeContext<'a, 'tcx> {
None
};
+ // if this is an impl of `CoerceUnsized`, create its
+ // "unsized info", else just store None
+ let coerce_unsized_info =
+ trait_ref.and_then(|t| {
+ if Some(t.def_id) == tcx.lang_items.coerce_unsized_trait() {
+ Some(ty::queries::coerce_unsized_info::get(tcx, item.span, def_id))
+ } else {
+ None
+ }
+ });
+
let data = ImplData {
polarity: polarity,
parent_impl: parent,
- coerce_unsized_kind: tcx.maps.custom_coerce_unsized_kind
- .borrow()
- .get(&def_id)
- .cloned(),
+ coerce_unsized_info: coerce_unsized_info,
trait_ref: trait_ref.map(|trait_ref| self.lazy(&trait_ref)),
};
diff --git a/src/librustc_metadata/schema.rs b/src/librustc_metadata/schema.rs
index 4a20913d0b3fd..abb482a50ebc2 100644
--- a/src/librustc_metadata/schema.rs
+++ b/src/librustc_metadata/schema.rs
@@ -285,7 +285,9 @@ pub struct TraitData<'tcx> {
pub struct ImplData<'tcx> {
pub polarity: hir::ImplPolarity,
pub parent_impl: Option<DefId>,
- pub coerce_unsized_kind: Option<ty::adjustment::CustomCoerceUnsized>,
+
+ /// This is `Some` only for impls of `CoerceUnsized`.
+ pub coerce_unsized_info: Option<ty::adjustment::CoerceUnsizedInfo>,
pub trait_ref: Option<Lazy<ty::TraitRef<'tcx>>>,
}
diff --git a/src/librustc_trans/monomorphize.rs b/src/librustc_trans/monomorphize.rs
index fcf6937d4b6d5..382ca8ef01001 100644
--- a/src/librustc_trans/monomorphize.rs
+++ b/src/librustc_trans/monomorphize.rs
@@ -287,7 +287,7 @@ pub fn custom_coerce_unsize_info<'scx, 'tcx>(scx: &SharedCrateContext<'scx, 'tcx
match fulfill_obligation(scx, DUMMY_SP, trait_ref) {
traits::VtableImpl(traits::VtableImplData { impl_def_id, .. }) => {
- scx.tcx().custom_coerce_unsized_kind(impl_def_id)
+ scx.tcx().coerce_unsized_info(impl_def_id).custom_kind.unwrap()
}
vtable => {
bug!("invalid CoerceUnsized vtable: {:?}", vtable);
diff --git a/src/librustc_typeck/coherence/builtin.rs b/src/librustc_typeck/coherence/builtin.rs
index 3cdf9fc93ae60..47b41a75cf531 100644
--- a/src/librustc_typeck/coherence/builtin.rs
+++ b/src/librustc_typeck/coherence/builtin.rs
@@ -18,6 +18,7 @@ use rustc::traits::{self, ObligationCause, Reveal};
use rustc::ty::{self, Ty, TyCtxt};
use rustc::ty::ParameterEnvironment;
use rustc::ty::TypeFoldable;
+use rustc::ty::adjustment::CoerceUnsizedInfo;
use rustc::ty::subst::Subst;
use rustc::ty::util::CopyImplementationError;
use rustc::infer;
@@ -159,11 +160,26 @@ fn visit_implementation_of_copy<'a, 'tcx>(tcx: TyCtxt<'a, 'tcx, 'tcx>,
}
fn visit_implementation_of_coerce_unsized<'a, 'tcx>(tcx: TyCtxt<'a, 'tcx, 'tcx>,
- coerce_unsized_trait: DefId,
+ _: DefId,
impl_did: DefId) {
debug!("visit_implementation_of_coerce_unsized: impl_did={:?}",
impl_did);
+ // Just compute this for the side-effects, in particular reporting
+ // errors; other parts of the code may demand it for the info of
+ // course.
+ if impl_did.is_local() {
+ let span = tcx.def_span(impl_did);
+ ty::queries::coerce_unsized_info::get(tcx, span, impl_did);
+ }
+}
+
+pub fn coerce_unsized_info<'a, 'tcx>(tcx: TyCtxt<'a, 'tcx, 'tcx>,
+ impl_did: DefId)
+ -> CoerceUnsizedInfo {
+ debug!("compute_coerce_unsized_info(impl_did={:?})", impl_did);
+ let coerce_unsized_trait = tcx.lang_items.coerce_unsized_trait().unwrap();
+
let unsize_trait = match tcx.lang_items.require(UnsizeTraitLangItem) {
Ok(id) => id,
Err(err) => {
@@ -171,16 +187,14 @@ fn visit_implementation_of_coerce_unsized<'a, 'tcx>(tcx: TyCtxt<'a, 'tcx, 'tcx>,
}
};
- let impl_node_id = if let Some(n) = tcx.hir.as_local_node_id(impl_did) {
- n
- } else {
- debug!("visit_implementation_of_coerce_unsized(): impl not \
- in this crate");
- return;
- };
+ // this provider should only get invoked for local def-ids
+ let impl_node_id = tcx.hir.as_local_node_id(impl_did).unwrap_or_else(|| {
+ bug!("coerce_unsized_info: invoked for non-local def-id {:?}", impl_did)
+ });
let source = tcx.item_type(impl_did);
let trait_ref = tcx.impl_trait_ref(impl_did).unwrap();
+ assert_eq!(trait_ref.def_id, coerce_unsized_trait);
let target = trait_ref.substs.type_at(1);
debug!("visit_implementation_of_coerce_unsized: {:?} -> {:?} (bound)",
source,
@@ -192,6 +206,8 @@ fn visit_implementation_of_coerce_unsized<'a, 'tcx>(tcx: TyCtxt<'a, 'tcx, 'tcx>,
let target = target.subst(tcx, ¶m_env.free_substs);
assert!(!source.has_escaping_regions());
+ let err_info = CoerceUnsizedInfo { custom_kind: None };
+
debug!("visit_implementation_of_coerce_unsized: {:?} -> {:?} (free)",
source,
target);
@@ -234,7 +250,7 @@ fn visit_implementation_of_coerce_unsized<'a, 'tcx>(tcx: TyCtxt<'a, 'tcx, 'tcx>,
definition; expected {}, found {}",
source_path,
target_path);
- return;
+ return err_info;
}
let fields = &def_a.struct_variant().fields;
@@ -268,7 +284,7 @@ fn visit_implementation_of_coerce_unsized<'a, 'tcx>(tcx: TyCtxt<'a, 'tcx, 'tcx>,
"the trait `CoerceUnsized` may only be implemented \
for a coercion between structures with one field \
being coerced, none found");
- return;
+ return err_info;
} else if diff_fields.len() > 1 {
let item = tcx.hir.expect_item(impl_node_id);
let span = if let ItemImpl(.., Some(ref t), _, _) = item.node {
@@ -295,7 +311,7 @@ fn visit_implementation_of_coerce_unsized<'a, 'tcx>(tcx: TyCtxt<'a, 'tcx, 'tcx>,
.join(", ")));
err.span_label(span, &format!("requires multiple coercions"));
err.emit();
- return;
+ return err_info;
}
let (i, a, b) = diff_fields[0];
@@ -309,7 +325,7 @@ fn visit_implementation_of_coerce_unsized<'a, 'tcx>(tcx: TyCtxt<'a, 'tcx, 'tcx>,
E0376,
"the trait `CoerceUnsized` may only be implemented \
for a coercion between structures");
- return;
+ return err_info;
}
};
@@ -331,8 +347,8 @@ fn visit_implementation_of_coerce_unsized<'a, 'tcx>(tcx: TyCtxt<'a, 'tcx, 'tcx>,
.caller_bounds);
infcx.resolve_regions_and_report_errors(&free_regions, impl_node_id);
- if let Some(kind) = kind {
- tcx.maps.custom_coerce_unsized_kind.borrow_mut().insert(impl_did, kind);
+ CoerceUnsizedInfo {
+ custom_kind: kind
}
- });
+ })
}
diff --git a/src/librustc_typeck/coherence/mod.rs b/src/librustc_typeck/coherence/mod.rs
index 9ecf42daeaae5..6abd061e81f2a 100644
--- a/src/librustc_typeck/coherence/mod.rs
+++ b/src/librustc_typeck/coherence/mod.rs
@@ -102,9 +102,12 @@ fn enforce_trait_manually_implementable(tcx: TyCtxt, impl_def_id: DefId, trait_d
}
pub fn provide(providers: &mut Providers) {
+ use self::builtin::coerce_unsized_info;
+
*providers = Providers {
coherent_trait,
coherent_inherent_impls,
+ coerce_unsized_info,
..*providers
};
}
From 8e6b10a6cb349deab30fa0fb507a8c73cae6ec68 Mon Sep 17 00:00:00 2001
From: Niko Matsakis <niko@alum.mit.edu>
Date: Mon, 20 Mar 2017 16:43:54 -0400
Subject: [PATCH 2/3] move `check` to the top of the file, where I would expect
to find it
Top-down, top-down!
---
src/librustc_typeck/coherence/inherent.rs | 13 +++++++------
1 file changed, 7 insertions(+), 6 deletions(-)
diff --git a/src/librustc_typeck/coherence/inherent.rs b/src/librustc_typeck/coherence/inherent.rs
index e3b4ba9eb1b9e..9abf233de1f9e 100644
--- a/src/librustc_typeck/coherence/inherent.rs
+++ b/src/librustc_typeck/coherence/inherent.rs
@@ -19,6 +19,13 @@ use rustc::ty::{self, TyCtxt};
use syntax::ast;
use syntax_pos::Span;
+pub fn check<'a, 'tcx>(tcx: TyCtxt<'a, 'tcx, 'tcx>) {
+ tcx.visit_all_item_likes_in_krate(DepNode::CoherenceCheckImpl,
+ &mut InherentCollect { tcx });
+ tcx.visit_all_item_likes_in_krate(DepNode::CoherenceOverlapCheckSpecial,
+ &mut InherentOverlapChecker { tcx });
+}
+
struct InherentCollect<'a, 'tcx: 'a> {
tcx: TyCtxt<'a, 'tcx, 'tcx>
}
@@ -348,9 +355,3 @@ impl<'a, 'tcx, 'v> ItemLikeVisitor<'v> for InherentOverlapChecker<'a, 'tcx> {
}
}
-pub fn check<'a, 'tcx>(tcx: TyCtxt<'a, 'tcx, 'tcx>) {
- tcx.visit_all_item_likes_in_krate(DepNode::CoherenceCheckImpl,
- &mut InherentCollect { tcx });
- tcx.visit_all_item_likes_in_krate(DepNode::CoherenceOverlapCheckSpecial,
- &mut InherentOverlapChecker { tcx });
-}
From a29ae3052aa9c84cecab226b9a1f1fee4e5b78d4 Mon Sep 17 00:00:00 2001
From: Niko Matsakis <niko@alum.mit.edu>
Date: Mon, 20 Mar 2017 18:35:16 -0400
Subject: [PATCH 3/3] convert inherent-impl-related things to on-demand queries
There are now 3 queries:
- inherent_impls(def-id): for a given type, get a `Rc<Vec<DefId>>` with
all its inherent impls. This internally uses `crate_inherent_impls`,
doing some hacks to keep the current deps (which, btw, are not clearly
correct).
- crate_inherent_impls(crate): gathers up a map from types
to `Rc<Vec<DefId>>`, touching the entire krate, possibly generating
errors.
- crate_inherent_impls_overlap_check(crate): performs overlap checks
between the inherent impls for a given type, generating errors.
---
src/librustc/dep_graph/dep_node.rs | 2 -
src/librustc/dep_graph/dep_tracking_map.rs | 15 --
src/librustc/middle/cstore.rs | 2 -
src/librustc/ty/maps.rs | 26 ++-
src/librustc/ty/mod.rs | 43 ++---
src/librustc_metadata/cstore_impl.rs | 7 +-
src/librustc_typeck/check/method/probe.rs | 11 +-
.../{inherent.rs => inherent_impls.rs} | 180 +++++++-----------
.../coherence/inherent_impls_overlap.rs | 102 ++++++++++
src/librustc_typeck/coherence/mod.rs | 17 +-
src/librustdoc/clean/inline.rs | 8 +-
11 files changed, 227 insertions(+), 186 deletions(-)
rename src/librustc_typeck/coherence/{inherent.rs => inherent_impls.rs} (71%)
create mode 100644 src/librustc_typeck/coherence/inherent_impls_overlap.rs
diff --git a/src/librustc/dep_graph/dep_node.rs b/src/librustc/dep_graph/dep_node.rs
index 399af258e9251..c4cbbc17d51df 100644
--- a/src/librustc/dep_graph/dep_node.rs
+++ b/src/librustc/dep_graph/dep_node.rs
@@ -74,7 +74,6 @@ pub enum DepNode<D: Clone + Debug> {
CoherenceCheckImpl(D),
CoherenceOverlapCheck(D),
CoherenceOverlapCheckSpecial(D),
- CoherenceOverlapInherentCheck(D),
CoherenceOrphanCheck(D),
Variance,
WfCheck(D),
@@ -251,7 +250,6 @@ impl<D: Clone + Debug> DepNode<D> {
CoherenceCheckImpl(ref d) => op(d).map(CoherenceCheckImpl),
CoherenceOverlapCheck(ref d) => op(d).map(CoherenceOverlapCheck),
CoherenceOverlapCheckSpecial(ref d) => op(d).map(CoherenceOverlapCheckSpecial),
- CoherenceOverlapInherentCheck(ref d) => op(d).map(CoherenceOverlapInherentCheck),
CoherenceOrphanCheck(ref d) => op(d).map(CoherenceOrphanCheck),
WfCheck(ref d) => op(d).map(WfCheck),
TypeckItemType(ref d) => op(d).map(TypeckItemType),
diff --git a/src/librustc/dep_graph/dep_tracking_map.rs b/src/librustc/dep_graph/dep_tracking_map.rs
index 0f3108df9a822..b6a2360211cac 100644
--- a/src/librustc/dep_graph/dep_tracking_map.rs
+++ b/src/librustc/dep_graph/dep_tracking_map.rs
@@ -81,21 +81,6 @@ impl<M: DepTrackingMapConfig> DepTrackingMap<M> {
pub fn keys(&self) -> Vec<M::Key> {
self.map.keys().cloned().collect()
}
-
- /// Append `elem` to the vector stored for `k`, creating a new vector if needed.
- /// This is considered a write to `k`.
- ///
- /// NOTE: Caution is required when using this method. You should
- /// be sure that nobody is **reading from the vector** while you
- /// are writing to it. Eventually, it'd be nice to remove this.
- pub fn push<E: Clone>(&mut self, k: M::Key, elem: E)
- where M: DepTrackingMapConfig<Value=Vec<E>>
- {
- self.write(&k);
- self.map.entry(k)
- .or_insert(Vec::new())
- .push(elem);
- }
}
impl<M: DepTrackingMapConfig> MemoizationMap for RefCell<DepTrackingMap<M>> {
diff --git a/src/librustc/middle/cstore.rs b/src/librustc/middle/cstore.rs
index 225d6fc9bb2b2..50ec6f26d4b82 100644
--- a/src/librustc/middle/cstore.rs
+++ b/src/librustc/middle/cstore.rs
@@ -176,7 +176,6 @@ pub trait CrateStore {
fn item_generics_cloned(&self, def: DefId) -> ty::Generics;
fn item_attrs(&self, def_id: DefId) -> Vec<ast::Attribute>;
fn fn_arg_names(&self, did: DefId) -> Vec<ast::Name>;
- fn inherent_implementations_for_type(&self, def_id: DefId) -> Vec<DefId>;
// trait info
fn implementations_of_trait(&self, filter: Option<DefId>) -> Vec<DefId>;
@@ -310,7 +309,6 @@ impl CrateStore for DummyCrateStore {
{ bug!("item_generics_cloned") }
fn item_attrs(&self, def_id: DefId) -> Vec<ast::Attribute> { bug!("item_attrs") }
fn fn_arg_names(&self, did: DefId) -> Vec<ast::Name> { bug!("fn_arg_names") }
- fn inherent_implementations_for_type(&self, def_id: DefId) -> Vec<DefId> { vec![] }
// trait info
fn implementations_of_trait(&self, filter: Option<DefId>) -> Vec<DefId> { vec![] }
diff --git a/src/librustc/ty/maps.rs b/src/librustc/ty/maps.rs
index d4214dc429ced..87fe27d92fca6 100644
--- a/src/librustc/ty/maps.rs
+++ b/src/librustc/ty/maps.rs
@@ -12,7 +12,7 @@ use dep_graph::{DepGraph, DepNode, DepTrackingMap, DepTrackingMapConfig};
use hir::def_id::{CrateNum, DefId, LOCAL_CRATE};
use middle::const_val::ConstVal;
use mir;
-use ty::{self, Ty, TyCtxt};
+use ty::{self, CrateInherentImpls, Ty, TyCtxt};
use rustc_data_structures::indexed_vec::IndexVec;
use std::cell::{RefCell, RefMut};
@@ -176,9 +176,15 @@ impl<'tcx> QueryDescription for queries::coherent_trait<'tcx> {
}
}
-impl<'tcx> QueryDescription for queries::coherent_inherent_impls<'tcx> {
+impl<'tcx> QueryDescription for queries::crate_inherent_impls<'tcx> {
+ fn describe(_: TyCtxt, k: CrateNum) -> String {
+ format!("all inherent impls defined in crate `{:?}`", k)
+ }
+}
+
+impl<'tcx> QueryDescription for queries::crate_inherent_impls_overlap_check<'tcx> {
fn describe(_: TyCtxt, _: CrateNum) -> String {
- format!("coherence checking all inherent impls")
+ format!("check for overlap between inherent impls defined in this crate")
}
}
@@ -368,7 +374,7 @@ define_maps! { <'tcx>
/// Maps a DefId of a type to a list of its inherent impls.
/// Contains implementations of methods that are inherent to a type.
/// Methods in these implementations don't need to be exported.
- pub inherent_impls: InherentImpls(DefId) -> Vec<DefId>,
+ pub inherent_impls: InherentImpls(DefId) -> Rc<Vec<DefId>>,
/// Maps from the def-id of a function/method or const/static
/// to its MIR. Mutation is done at an item granularity to
@@ -400,7 +406,15 @@ define_maps! { <'tcx>
pub coherent_trait: coherent_trait_dep_node((CrateNum, DefId)) -> (),
- pub coherent_inherent_impls: coherent_inherent_impls_dep_node(CrateNum) -> (),
+ /// Gets a complete map from all types to their inherent impls.
+ /// Not meant to be used directly outside of coherence.
+ /// (Defined only for LOCAL_CRATE)
+ pub crate_inherent_impls: crate_inherent_impls_dep_node(CrateNum) -> CrateInherentImpls,
+
+ /// Checks all types in the krate for overlap in their inherent impls. Reports errors.
+ /// Not meant to be used directly outside of coherence.
+ /// (Defined only for LOCAL_CRATE)
+ pub crate_inherent_impls_overlap_check: crate_inherent_impls_dep_node(CrateNum) -> (),
/// Results of evaluating monomorphic constants embedded in
/// other items, such as enum variant explicit discriminants.
@@ -413,7 +427,7 @@ fn coherent_trait_dep_node((_, def_id): (CrateNum, DefId)) -> DepNode<DefId> {
DepNode::CoherenceCheckTrait(def_id)
}
-fn coherent_inherent_impls_dep_node(_: CrateNum) -> DepNode<DefId> {
+fn crate_inherent_impls_dep_node(_: CrateNum) -> DepNode<DefId> {
DepNode::Coherence
}
diff --git a/src/librustc/ty/mod.rs b/src/librustc/ty/mod.rs
index d140426995812..d19f2ba2fadb1 100644
--- a/src/librustc/ty/mod.rs
+++ b/src/librustc/ty/mod.rs
@@ -31,7 +31,7 @@ use ty::subst::{Subst, Substs};
use ty::util::IntTypeExt;
use ty::walk::TypeWalker;
use util::common::MemoizationMap;
-use util::nodemap::{NodeSet, FxHashMap};
+use util::nodemap::{NodeSet, DefIdMap, FxHashMap};
use serialize::{self, Encodable, Encoder};
use std::borrow::Cow;
@@ -2345,34 +2345,6 @@ impl<'a, 'gcx, 'tcx> TyCtxt<'a, 'gcx, 'tcx> {
def.flags.get().intersects(TraitFlags::HAS_DEFAULT_IMPL)
}
- /// Populates the type context with all the inherent implementations for
- /// the given type if necessary.
- pub fn populate_inherent_implementations_for_type_if_necessary(self,
- span: Span,
- type_id: DefId) {
- if type_id.is_local() {
- // Make sure coherence of inherent impls ran already.
- ty::queries::coherent_inherent_impls::force(self, span, LOCAL_CRATE);
- return
- }
-
- // The type is not local, hence we are reading this out of
- // metadata and don't need to track edges.
- let _ignore = self.dep_graph.in_ignore();
-
- if self.populated_external_types.borrow().contains(&type_id) {
- return
- }
-
- debug!("populate_inherent_implementations_for_type_if_necessary: searching for {:?}",
- type_id);
-
- let inherent_impls = self.sess.cstore.inherent_implementations_for_type(type_id);
-
- self.maps.inherent_impls.borrow_mut().insert(type_id, inherent_impls);
- self.populated_external_types.borrow_mut().insert(type_id);
- }
-
/// Populates the type context with all the implementations for the given
/// trait if necessary.
pub fn populate_implementations_for_trait_if_necessary(self, trait_id: DefId) {
@@ -2637,3 +2609,16 @@ pub fn provide(providers: &mut ty::maps::Providers) {
..*providers
};
}
+
+
+/// A map for the local crate mapping each type to a vector of its
+/// inherent impls. This is not meant to be used outside of coherence;
+/// rather, you should request the vector for a specific type via
+/// `ty::queries::inherent_impls::get(def_id)` so as to minimize your
+/// dependencies (constructing this map requires touching the entire
+/// crate).
+#[derive(Clone, Debug)]
+pub struct CrateInherentImpls {
+ pub inherent_impls: DefIdMap<Rc<Vec<DefId>>>,
+}
+
diff --git a/src/librustc_metadata/cstore_impl.rs b/src/librustc_metadata/cstore_impl.rs
index 7cac201f14f76..9b781d28f88dc 100644
--- a/src/librustc_metadata/cstore_impl.rs
+++ b/src/librustc_metadata/cstore_impl.rs
@@ -109,6 +109,7 @@ provide! { <'tcx> tcx, def_id, cdata
typeck_tables => { cdata.item_body_tables(def_id.index, tcx) }
closure_kind => { cdata.closure_kind(def_id.index) }
closure_type => { cdata.closure_ty(def_id.index, tcx) }
+ inherent_impls => { Rc::new(cdata.get_inherent_implementations_for_type(def_id.index)) }
}
impl CrateStore for cstore::CStore {
@@ -162,12 +163,6 @@ impl CrateStore for cstore::CStore {
self.get_crate_data(did.krate).get_fn_arg_names(did.index)
}
- fn inherent_implementations_for_type(&self, def_id: DefId) -> Vec<DefId>
- {
- self.dep_graph.read(DepNode::MetaData(def_id));
- self.get_crate_data(def_id.krate).get_inherent_implementations_for_type(def_id.index)
- }
-
fn implementations_of_trait(&self, filter: Option<DefId>) -> Vec<DefId>
{
if let Some(def_id) = filter {
diff --git a/src/librustc_typeck/check/method/probe.rs b/src/librustc_typeck/check/method/probe.rs
index dfa7ababca0bb..5b0418921563a 100644
--- a/src/librustc_typeck/check/method/probe.rs
+++ b/src/librustc_typeck/check/method/probe.rs
@@ -479,14 +479,9 @@ impl<'a, 'gcx, 'tcx> ProbeContext<'a, 'gcx, 'tcx> {
}
fn assemble_inherent_impl_candidates_for_type(&mut self, def_id: DefId) {
- // Read the inherent implementation candidates for this type from the
- // metadata if necessary.
- self.tcx.populate_inherent_implementations_for_type_if_necessary(self.span, def_id);
-
- if let Some(impl_infos) = self.tcx.maps.inherent_impls.borrow().get(&def_id) {
- for &impl_def_id in impl_infos.iter() {
- self.assemble_inherent_impl_probe(impl_def_id);
- }
+ let impl_def_ids = ty::queries::inherent_impls::get(self.tcx, self.span, def_id);
+ for &impl_def_id in impl_def_ids.iter() {
+ self.assemble_inherent_impl_probe(impl_def_id);
}
}
diff --git a/src/librustc_typeck/coherence/inherent.rs b/src/librustc_typeck/coherence/inherent_impls.rs
similarity index 71%
rename from src/librustc_typeck/coherence/inherent.rs
rename to src/librustc_typeck/coherence/inherent_impls.rs
index 9abf233de1f9e..3a39df505eb07 100644
--- a/src/librustc_typeck/coherence/inherent.rs
+++ b/src/librustc_typeck/coherence/inherent_impls.rs
@@ -8,26 +8,82 @@
// option. This file may not be copied, modified, or distributed
// except according to those terms.
+//! The code in this module gathers up all of the inherent impls in
+//! the current crate and organizes them in a map. It winds up
+//! touching the whole crate and thus must be recomputed completely
+//! for any change, but it is very cheap to compute. In practice, most
+//! code in the compiler never *directly* requests this map. Instead,
+//! it requests the inherent impls specific to some type (via
+//! `ty::queries::inherent_impls::get(def_id)`). That value, however,
+//! is computed by selecting an idea from this table.
+
use rustc::dep_graph::DepNode;
-use rustc::hir::def_id::DefId;
+use rustc::hir::def_id::{CrateNum, DefId, LOCAL_CRATE};
use rustc::hir;
use rustc::hir::itemlikevisit::ItemLikeVisitor;
-use rustc::lint;
-use rustc::traits::{self, Reveal};
-use rustc::ty::{self, TyCtxt};
+use rustc::ty::{self, CrateInherentImpls, TyCtxt};
+use rustc::util::nodemap::DefIdMap;
+use std::rc::Rc;
use syntax::ast;
-use syntax_pos::Span;
+use syntax_pos::{DUMMY_SP, Span};
+
+/// On-demand query: yields a map containing all types mapped to their inherent impls.
+pub fn crate_inherent_impls<'a, 'tcx>(tcx: TyCtxt<'a, 'tcx, 'tcx>,
+ crate_num: CrateNum)
+ -> CrateInherentImpls {
+ assert_eq!(crate_num, LOCAL_CRATE);
+
+ let krate = tcx.hir.krate();
+ let mut collect = InherentCollect {
+ tcx,
+ impls_map: CrateInherentImpls {
+ inherent_impls: DefIdMap()
+ }
+ };
+ krate.visit_all_item_likes(&mut collect);
+ collect.impls_map
+}
+
+/// On-demand query: yields a vector of the inherent impls for a specific type.
+pub fn inherent_impls<'a, 'tcx>(tcx: TyCtxt<'a, 'tcx, 'tcx>,
+ ty_def_id: DefId)
+ -> Rc<Vec<DefId>> {
+ assert!(ty_def_id.is_local());
+
+ // NB. Until we adopt the red-green dep-tracking algorithm (see
+ // [the plan] for details on that), we do some hackery here to get
+ // the dependencies correct. Basically, we use a `with_ignore` to
+ // read the result we want. If we didn't have the `with_ignore`,
+ // we would wind up with a dependency on the entire crate, which
+ // we don't want. Then we go and add dependencies on all the impls
+ // in the result (which is what we wanted).
+ //
+ // The result is a graph with an edge from `Hir(I)` for every impl
+ // `I` defined on some type `T` to `CoherentInherentImpls(T)`,
+ // thus ensuring that if any of those impls change, the set of
+ // inherent impls is considered dirty.
+ //
+ // [the plan]: https://github.com/rust-lang/rust-roadmap/issues/4
+
+ let result = tcx.dep_graph.with_ignore(|| {
+ let crate_map = ty::queries::crate_inherent_impls::get(tcx, DUMMY_SP, ty_def_id.krate);
+ match crate_map.inherent_impls.get(&ty_def_id) {
+ Some(v) => v.clone(),
+ None => Rc::new(vec![]),
+ }
+ });
+
+ for &impl_def_id in &result[..] {
+ tcx.dep_graph.read(DepNode::Hir(impl_def_id));
+ }
-pub fn check<'a, 'tcx>(tcx: TyCtxt<'a, 'tcx, 'tcx>) {
- tcx.visit_all_item_likes_in_krate(DepNode::CoherenceCheckImpl,
- &mut InherentCollect { tcx });
- tcx.visit_all_item_likes_in_krate(DepNode::CoherenceOverlapCheckSpecial,
- &mut InherentOverlapChecker { tcx });
+ result
}
struct InherentCollect<'a, 'tcx: 'a> {
- tcx: TyCtxt<'a, 'tcx, 'tcx>
+ tcx: TyCtxt<'a, 'tcx, 'tcx>,
+ impls_map: CrateInherentImpls,
}
impl<'a, 'tcx, 'v> ItemLikeVisitor<'v> for InherentCollect<'a, 'tcx> {
@@ -216,25 +272,19 @@ impl<'a, 'tcx, 'v> ItemLikeVisitor<'v> for InherentCollect<'a, 'tcx> {
}
impl<'a, 'tcx> InherentCollect<'a, 'tcx> {
- fn check_def_id(&self, item: &hir::Item, def_id: DefId) {
+ fn check_def_id(&mut self, item: &hir::Item, def_id: DefId) {
if def_id.is_local() {
// Add the implementation to the mapping from implementation to base
// type def ID, if there is a base type for this implementation and
// the implementation does not have any associated traits.
let impl_def_id = self.tcx.hir.local_def_id(item.id);
+ let mut rc_vec = self.impls_map.inherent_impls
+ .entry(def_id)
+ .or_insert_with(|| Rc::new(vec![]));
- // Subtle: it'd be better to collect these into a local map
- // and then write the vector only once all items are known,
- // but that leads to degenerate dep-graphs. The problem is
- // that the write of that big vector winds up having reads
- // from *all* impls in the krate, since we've lost the
- // precision basically. This would be ok in the firewall
- // model so once we've made progess towards that we can modify
- // the strategy here. In the meantime, using `push` is ok
- // because we are doing this as a pre-pass before anyone
- // actually reads from `inherent_impls` -- and we know this is
- // true beacuse we hold the refcell lock.
- self.tcx.maps.inherent_impls.borrow_mut().push(def_id, impl_def_id);
+ // At this point, there should not be any clones of the
+ // `Rc`, so we can still safely push into it in place:
+ Rc::get_mut(&mut rc_vec).unwrap().push(impl_def_id);
} else {
struct_span_err!(self.tcx.sess,
item.span,
@@ -273,85 +323,3 @@ impl<'a, 'tcx> InherentCollect<'a, 'tcx> {
}
}
-struct InherentOverlapChecker<'a, 'tcx: 'a> {
- tcx: TyCtxt<'a, 'tcx, 'tcx>
-}
-
-impl<'a, 'tcx> InherentOverlapChecker<'a, 'tcx> {
- fn check_for_common_items_in_impls(&self, impl1: DefId, impl2: DefId) {
- #[derive(Copy, Clone, PartialEq)]
- enum Namespace {
- Type,
- Value,
- }
-
- let name_and_namespace = |def_id| {
- let item = self.tcx.associated_item(def_id);
- (item.name, match item.kind {
- ty::AssociatedKind::Type => Namespace::Type,
- ty::AssociatedKind::Const |
- ty::AssociatedKind::Method => Namespace::Value,
- })
- };
-
- let impl_items1 = self.tcx.associated_item_def_ids(impl1);
- let impl_items2 = self.tcx.associated_item_def_ids(impl2);
-
- for &item1 in &impl_items1[..] {
- let (name, namespace) = name_and_namespace(item1);
-
- for &item2 in &impl_items2[..] {
- if (name, namespace) == name_and_namespace(item2) {
- let msg = format!("duplicate definitions with name `{}`", name);
- let node_id = self.tcx.hir.as_local_node_id(item1).unwrap();
- self.tcx.sess.add_lint(lint::builtin::OVERLAPPING_INHERENT_IMPLS,
- node_id,
- self.tcx.span_of_impl(item1).unwrap(),
- msg);
- }
- }
- }
- }
-
- fn check_for_overlapping_inherent_impls(&self, ty_def_id: DefId) {
- let _task = self.tcx.dep_graph.in_task(DepNode::CoherenceOverlapInherentCheck(ty_def_id));
-
- let inherent_impls = self.tcx.maps.inherent_impls.borrow();
- let impls = match inherent_impls.get(&ty_def_id) {
- Some(impls) => impls,
- None => return,
- };
-
- for (i, &impl1_def_id) in impls.iter().enumerate() {
- for &impl2_def_id in &impls[(i + 1)..] {
- self.tcx.infer_ctxt((), Reveal::UserFacing).enter(|infcx| {
- if traits::overlapping_impls(&infcx, impl1_def_id, impl2_def_id).is_some() {
- self.check_for_common_items_in_impls(impl1_def_id, impl2_def_id)
- }
- });
- }
- }
- }
-}
-
-impl<'a, 'tcx, 'v> ItemLikeVisitor<'v> for InherentOverlapChecker<'a, 'tcx> {
- fn visit_item(&mut self, item: &'v hir::Item) {
- match item.node {
- hir::ItemEnum(..) |
- hir::ItemStruct(..) |
- hir::ItemTrait(..) |
- hir::ItemUnion(..) => {
- let type_def_id = self.tcx.hir.local_def_id(item.id);
- self.check_for_overlapping_inherent_impls(type_def_id);
- }
- _ => {}
- }
- }
-
- fn visit_trait_item(&mut self, _trait_item: &hir::TraitItem) {
- }
-
- fn visit_impl_item(&mut self, _impl_item: &hir::ImplItem) {
- }
-}
-
diff --git a/src/librustc_typeck/coherence/inherent_impls_overlap.rs b/src/librustc_typeck/coherence/inherent_impls_overlap.rs
new file mode 100644
index 0000000000000..4b36072243c81
--- /dev/null
+++ b/src/librustc_typeck/coherence/inherent_impls_overlap.rs
@@ -0,0 +1,102 @@
+// Copyright 2017 The Rust Project Developers. See the COPYRIGHT
+// file at the top-level directory of this distribution and at
+// http://rust-lang.org/COPYRIGHT.
+//
+// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
+// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
+// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
+// option. This file may not be copied, modified, or distributed
+// except according to those terms.
+
+use rustc::hir::def_id::{CrateNum, DefId, LOCAL_CRATE};
+use rustc::hir;
+use rustc::hir::itemlikevisit::ItemLikeVisitor;
+use rustc::lint;
+use rustc::traits::{self, Reveal};
+use rustc::ty::{self, TyCtxt};
+
+use syntax_pos::DUMMY_SP;
+
+pub fn crate_inherent_impls_overlap_check<'a, 'tcx>(tcx: TyCtxt<'a, 'tcx, 'tcx>,
+ crate_num: CrateNum) {
+ assert_eq!(crate_num, LOCAL_CRATE);
+ let krate = tcx.hir.krate();
+ krate.visit_all_item_likes(&mut InherentOverlapChecker { tcx });
+}
+
+struct InherentOverlapChecker<'a, 'tcx: 'a> {
+ tcx: TyCtxt<'a, 'tcx, 'tcx>
+}
+
+impl<'a, 'tcx> InherentOverlapChecker<'a, 'tcx> {
+ fn check_for_common_items_in_impls(&self, impl1: DefId, impl2: DefId) {
+ #[derive(Copy, Clone, PartialEq)]
+ enum Namespace {
+ Type,
+ Value,
+ }
+
+ let name_and_namespace = |def_id| {
+ let item = self.tcx.associated_item(def_id);
+ (item.name, match item.kind {
+ ty::AssociatedKind::Type => Namespace::Type,
+ ty::AssociatedKind::Const |
+ ty::AssociatedKind::Method => Namespace::Value,
+ })
+ };
+
+ let impl_items1 = self.tcx.associated_item_def_ids(impl1);
+ let impl_items2 = self.tcx.associated_item_def_ids(impl2);
+
+ for &item1 in &impl_items1[..] {
+ let (name, namespace) = name_and_namespace(item1);
+
+ for &item2 in &impl_items2[..] {
+ if (name, namespace) == name_and_namespace(item2) {
+ let msg = format!("duplicate definitions with name `{}`", name);
+ let node_id = self.tcx.hir.as_local_node_id(item1).unwrap();
+ self.tcx.sess.add_lint(lint::builtin::OVERLAPPING_INHERENT_IMPLS,
+ node_id,
+ self.tcx.span_of_impl(item1).unwrap(),
+ msg);
+ }
+ }
+ }
+ }
+
+ fn check_for_overlapping_inherent_impls(&self, ty_def_id: DefId) {
+ let impls = ty::queries::inherent_impls::get(self.tcx, DUMMY_SP, ty_def_id);
+
+ for (i, &impl1_def_id) in impls.iter().enumerate() {
+ for &impl2_def_id in &impls[(i + 1)..] {
+ self.tcx.infer_ctxt((), Reveal::UserFacing).enter(|infcx| {
+ if traits::overlapping_impls(&infcx, impl1_def_id, impl2_def_id).is_some() {
+ self.check_for_common_items_in_impls(impl1_def_id, impl2_def_id)
+ }
+ });
+ }
+ }
+ }
+}
+
+impl<'a, 'tcx, 'v> ItemLikeVisitor<'v> for InherentOverlapChecker<'a, 'tcx> {
+ fn visit_item(&mut self, item: &'v hir::Item) {
+ match item.node {
+ hir::ItemEnum(..) |
+ hir::ItemStruct(..) |
+ hir::ItemTrait(..) |
+ hir::ItemUnion(..) => {
+ let type_def_id = self.tcx.hir.local_def_id(item.id);
+ self.check_for_overlapping_inherent_impls(type_def_id);
+ }
+ _ => {}
+ }
+ }
+
+ fn visit_trait_item(&mut self, _trait_item: &hir::TraitItem) {
+ }
+
+ fn visit_impl_item(&mut self, _impl_item: &hir::ImplItem) {
+ }
+}
+
diff --git a/src/librustc_typeck/coherence/mod.rs b/src/librustc_typeck/coherence/mod.rs
index 6abd061e81f2a..b3a7b612dd5b8 100644
--- a/src/librustc_typeck/coherence/mod.rs
+++ b/src/librustc_typeck/coherence/mod.rs
@@ -24,7 +24,8 @@ use syntax::ast;
use syntax_pos::DUMMY_SP;
mod builtin;
-mod inherent;
+mod inherent_impls;
+mod inherent_impls_overlap;
mod orphan;
mod overlap;
mod unsafety;
@@ -103,10 +104,14 @@ fn enforce_trait_manually_implementable(tcx: TyCtxt, impl_def_id: DefId, trait_d
pub fn provide(providers: &mut Providers) {
use self::builtin::coerce_unsized_info;
+ use self::inherent_impls::{crate_inherent_impls, inherent_impls};
+ use self::inherent_impls_overlap::crate_inherent_impls_overlap_check;
*providers = Providers {
coherent_trait,
- coherent_inherent_impls,
+ crate_inherent_impls,
+ inherent_impls,
+ crate_inherent_impls_overlap_check,
coerce_unsized_info,
..*providers
};
@@ -126,10 +131,6 @@ fn coherent_trait<'a, 'tcx>(tcx: TyCtxt<'a, 'tcx, 'tcx>,
builtin::check_trait(tcx, def_id);
}
-fn coherent_inherent_impls<'a, 'tcx>(tcx: TyCtxt<'a, 'tcx, 'tcx>, _: CrateNum) {
- inherent::check(tcx);
-}
-
pub fn check_coherence<'a, 'tcx>(tcx: TyCtxt<'a, 'tcx, 'tcx>) {
let _task = tcx.dep_graph.in_task(DepNode::Coherence);
for &trait_def_id in tcx.hir.krate().trait_impls.keys() {
@@ -140,5 +141,7 @@ pub fn check_coherence<'a, 'tcx>(tcx: TyCtxt<'a, 'tcx, 'tcx>) {
orphan::check(tcx);
overlap::check_default_impls(tcx);
- ty::queries::coherent_inherent_impls::get(tcx, DUMMY_SP, LOCAL_CRATE);
+ // these queries are executed for side-effects (error reporting):
+ ty::queries::crate_inherent_impls::get(tcx, DUMMY_SP, LOCAL_CRATE);
+ ty::queries::crate_inherent_impls_overlap_check::get(tcx, DUMMY_SP, LOCAL_CRATE);
}
diff --git a/src/librustdoc/clean/inline.rs b/src/librustdoc/clean/inline.rs
index c4476483186c7..cc30fdf56fc34 100644
--- a/src/librustdoc/clean/inline.rs
+++ b/src/librustdoc/clean/inline.rs
@@ -232,14 +232,12 @@ fn build_type_alias(cx: &DocContext, did: DefId) -> clean::Typedef {
pub fn build_impls(cx: &DocContext, did: DefId) -> Vec<clean::Item> {
let tcx = cx.tcx;
- tcx.populate_inherent_implementations_for_type_if_necessary(DUMMY_SP, did);
let mut impls = Vec::new();
- if let Some(i) = tcx.maps.inherent_impls.borrow().get(&did) {
- for &did in i.iter() {
- build_impl(cx, did, &mut impls);
- }
+ for &did in ty::queries::inherent_impls::get(tcx, DUMMY_SP, did).iter() {
+ build_impl(cx, did, &mut impls);
}
+
// If this is the first time we've inlined something from another crate, then
// we inline *all* impls from all the crates into this crate. Note that there's
// currently no way for us to filter this based on type, and we likely need