Auto merge of #57755 - Centril:rollup, r=Centril

Rollup of 7 pull requests

Successful merges:

 - #57486 (Simplify `TokenStream` some more)
 - #57502 (make trait-aliases work across crates)
 - #57598 (Add missing unpretty option help message)
 - #57649 (privacy: Account for associated existential types)
 - #57659 (Fix release manifest generation)
 - #57699 (add applicability to remaining suggestions)
 - #57719 (Tweak `expand_node`)

Failed merges:

r? @ghost

Author: bors

src/librustc/hir/map/def_collector.rs

@@ -120,10 +120,10 @@ impl<'a> visit::Visitor<'a> for DefCollector<'a> {
         let def_data = match i.node {
             ItemKind::Impl(..) => DefPathData::Impl,
             ItemKind::Trait(..) => DefPathData::Trait(i.ident.as_interned_str()),
+            ItemKind::TraitAlias(..) => DefPathData::TraitAlias(i.ident.as_interned_str()),
             ItemKind::Enum(..) | ItemKind::Struct(..) | ItemKind::Union(..) |
-            ItemKind::TraitAlias(..) | ItemKind::Existential(..) |
-            ItemKind::ExternCrate(..) | ItemKind::ForeignMod(..) | ItemKind::Ty(..) =>
-                DefPathData::TypeNs(i.ident.as_interned_str()),
+            ItemKind::Existential(..) | ItemKind::ExternCrate(..) | ItemKind::ForeignMod(..) |
+            ItemKind::Ty(..) => DefPathData::TypeNs(i.ident.as_interned_str()),
             ItemKind::Mod(..) if i.ident == keywords::Invalid.ident() => {
                 return visit::walk_item(self, i);
             }

src/librustc/hir/map/definitions.rs

@@ -373,7 +373,9 @@ pub enum DefPathData {
     /// GlobalMetaData identifies a piece of crate metadata that is global to
     /// a whole crate (as opposed to just one item). GlobalMetaData components
     /// are only supposed to show up right below the crate root.
-    GlobalMetaData(InternedString)
+    GlobalMetaData(InternedString),
+    /// A trait alias.
+    TraitAlias(InternedString),
 }
 
 #[derive(Copy, Clone, Hash, PartialEq, Eq, PartialOrd, Ord, Debug,
@@ -615,6 +617,7 @@ impl DefPathData {
         match *self {
             TypeNs(name) |
             Trait(name) |
+            TraitAlias(name) |
             AssocTypeInTrait(name) |
             AssocTypeInImpl(name) |
             AssocExistentialInImpl(name) |
@@ -642,6 +645,7 @@ impl DefPathData {
         let s = match *self {
             TypeNs(name) |
             Trait(name) |
+            TraitAlias(name) |
             AssocTypeInTrait(name) |
             AssocTypeInImpl(name) |
             AssocExistentialInImpl(name) |

src/librustc/hir/mod.rs

@@ -10,6 +10,7 @@ pub use self::PrimTy::*;
 pub use self::UnOp::*;
 pub use self::UnsafeSource::*;
 
+use errors::FatalError;
 use hir::def::Def;
 use hir::def_id::{DefId, DefIndex, LocalDefId, CRATE_DEF_INDEX};
 use util::nodemap::{NodeMap, FxHashSet};
@@ -2055,6 +2056,20 @@ pub struct TraitRef {
     pub hir_ref_id: HirId,
 }
 
+impl TraitRef {
+    /// Get the `DefId` of the referenced trait. It _must_ actually be a trait or trait alias.
+    pub fn trait_def_id(&self) -> DefId {
+        match self.path.def {
+            Def::Trait(did) => did,
+            Def::TraitAlias(did) => did,
+            Def::Err => {
+                FatalError.raise();
+            }
+            _ => unreachable!(),
+        }
+    }
+}
+
 #[derive(Clone, RustcEncodable, RustcDecodable, Debug)]
 pub struct PolyTraitRef {
     /// The `'a` in `<'a> Foo<&'a T>`

src/librustc/ich/impls_syntax.rs

@@ -258,7 +258,7 @@ for tokenstream::TokenTree {
             tokenstream::TokenTree::Delimited(span, delim, ref tts) => {
                 span.hash_stable(hcx, hasher);
                 std_hash::Hash::hash(&delim, hasher);
-                for sub_tt in tts.stream().trees() {
+                for sub_tt in tts.trees() {
                     sub_tt.hash_stable(hcx, hasher);
                 }
             }

src/librustc/infer/lexical_region_resolve/mod.rs

@@ -186,34 +186,39 @@ impl<'cx, 'gcx, 'tcx> LexicalResolver<'cx, 'gcx, 'tcx> {
     }
 
     fn expansion(&self, var_values: &mut LexicalRegionResolutions<'tcx>) {
-        self.iterate_until_fixed_point("Expansion", |constraint, origin| {
-            debug!("expansion: constraint={:?} origin={:?}", constraint, origin);
-            match *constraint {
+        self.iterate_until_fixed_point("Expansion", |constraint| {
+            debug!("expansion: constraint={:?}", constraint);
+            let (a_region, b_vid, b_data, retain) = match *constraint {
                 Constraint::RegSubVar(a_region, b_vid) => {
                     let b_data = var_values.value_mut(b_vid);
-                    (self.expand_node(a_region, b_vid, b_data), false)
+                    (a_region, b_vid, b_data, false)
                 }
                 Constraint::VarSubVar(a_vid, b_vid) => match *var_values.value(a_vid) {
-                    VarValue::ErrorValue => (false, false),
+                    VarValue::ErrorValue => return (false, false),
                     VarValue::Value(a_region) => {
-                        let b_node = var_values.value_mut(b_vid);
-                        let changed = self.expand_node(a_region, b_vid, b_node);
-                        let retain = match *b_node {
+                        let b_data = var_values.value_mut(b_vid);
+                        let retain = match *b_data {
                             VarValue::Value(ReStatic) | VarValue::ErrorValue => false,
                             _ => true
                         };
-                        (changed, retain)
+                        (a_region, b_vid, b_data, retain)
                     }
                 },
                 Constraint::RegSubReg(..) | Constraint::VarSubReg(..) => {
                     // These constraints are checked after expansion
                     // is done, in `collect_errors`.
-                    (false, false)
+                    return (false, false)
                 }
-            }
+            };
+
+            let changed = self.expand_node(a_region, b_vid, b_data);
+            (changed, retain)
         })
     }
 
+    // This function is very hot in some workloads. There's a single callsite
+    // so always inlining is ok even though it's large.
+    #[inline(always)]
     fn expand_node(
         &self,
         a_region: Region<'tcx>,
@@ -722,18 +727,17 @@ impl<'cx, 'gcx, 'tcx> LexicalResolver<'cx, 'gcx, 'tcx> {
     }
 
     fn iterate_until_fixed_point<F>(&self, tag: &str, mut body: F)
-    where
-        F: FnMut(&Constraint<'tcx>, &SubregionOrigin<'tcx>) -> (bool, bool),
+        where F: FnMut(&Constraint<'tcx>) -> (bool, bool),
     {
-        let mut constraints: SmallVec<[_; 16]> = self.data.constraints.iter().collect();
+        let mut constraints: SmallVec<[_; 16]> = self.data.constraints.keys().collect();
         let mut iteration = 0;
         let mut changed = true;
         while changed {
             changed = false;
             iteration += 1;
             debug!("---- {} Iteration {}{}", "#", tag, iteration);
-            constraints.retain(|(constraint, origin)| {
-                let (edge_changed, retain) = body(constraint, origin);
+            constraints.retain(|constraint| {
+                let (edge_changed, retain) = body(constraint);
                 if edge_changed {
                     debug!("Updated due to constraint {:?}", constraint);
                     changed = true;

src/librustc/session/config.rs

@@ -1353,10 +1353,15 @@ options! {DebuggingOptions, DebuggingSetter, basic_debugging_options,
     unpretty: Option<String> = (None, parse_unpretty, [UNTRACKED],
         "Present the input source, unstable (and less-pretty) variants;
         valid types are any of the types for `--pretty`, as well as:
+        `expanded`, `expanded,identified`,
+        `expanded,hygiene` (with internal representations),
         `flowgraph=<nodeid>` (graphviz formatted flowgraph for node),
+        `flowgraph,unlabelled=<nodeid>` (unlabelled graphviz formatted flowgraph for node),
         `everybody_loops` (all function bodies replaced with `loop {}`),
-        `hir` (the HIR), `hir,identified`, or
-        `hir,typed` (HIR with types for each node)."),
+        `hir` (the HIR), `hir,identified`,
+        `hir,typed` (HIR with types for each node),
+        `hir-tree` (dump the raw HIR),
+        `mir` (the MIR), or `mir-cfg` (graphviz formatted MIR)"),
     run_dsymutil: Option<bool> = (None, parse_opt_bool, [TRACKED],
         "run `dsymutil` and delete intermediate object files"),
     ui_testing: bool = (false, parse_bool, [UNTRACKED],

src/librustc/traits/select.rs

@@ -2198,7 +2198,7 @@ impl<'cx, 'gcx, 'tcx> SelectionContext<'cx, 'gcx, 'tcx> {
 
         let def_id = obligation.predicate.def_id();
 
-        if ty::is_trait_alias(self.tcx(), def_id) {
+        if self.tcx().is_trait_alias(def_id) {
             candidates.vec.push(TraitAliasCandidate(def_id.clone()));
         }
 

src/librustc/ty/item_path.rs

@@ -311,6 +311,7 @@ impl<'a, 'gcx, 'tcx> TyCtxt<'a, 'gcx, 'tcx> {
             data @ DefPathData::Misc |
             data @ DefPathData::TypeNs(..) |
             data @ DefPathData::Trait(..) |
+            data @ DefPathData::TraitAlias(..) |
             data @ DefPathData::AssocTypeInTrait(..) |
             data @ DefPathData::AssocTypeInImpl(..) |
             data @ DefPathData::AssocExistentialInImpl(..) |

src/librustc/ty/mod.rs

@@ -3170,18 +3170,6 @@ pub fn is_impl_trait_defn(tcx: TyCtxt<'_, '_, '_>, def_id: DefId) -> Option<DefI
     None
 }
 
-/// Returns `true` if `def_id` is a trait alias.
-pub fn is_trait_alias(tcx: TyCtxt<'_, '_, '_>, def_id: DefId) -> bool {
-    if let Some(node_id) = tcx.hir().as_local_node_id(def_id) {
-        if let Node::Item(item) = tcx.hir().get(node_id) {
-            if let hir::ItemKind::TraitAlias(..) = item.node {
-                return true;
-            }
-        }
-    }
-    false
-}
-
 /// See `ParamEnv` struct definition for details.
 fn param_env<'a, 'tcx>(tcx: TyCtxt<'a, 'tcx, 'tcx>,
                        def_id: DefId)

src/librustc/ty/util.rs

@@ -526,6 +526,15 @@ impl<'a, 'gcx, 'tcx> TyCtxt<'a, 'gcx, 'tcx> {
         }
     }
 
+    /// True if `def_id` refers to a trait alias (i.e., `trait Foo = ...;`).
+    pub fn is_trait_alias(self, def_id: DefId) -> bool {
+        if let DefPathData::TraitAlias(_) = self.def_key(def_id).disambiguated_data.data {
+            true
+        } else {
+            false
+        }
+    }
+
     /// True if this def-id refers to the implicit constructor for
     /// a tuple struct like `struct Foo(u32)`.
     pub fn is_struct_constructor(self, def_id: DefId) -> bool {