Refactor field expansion_data of Resolver to use a Mark instead of a u32.

src/librustc/hir/map/def_collector.rs

@@ -17,6 +17,7 @@ use hir::def_id::{CRATE_DEF_INDEX, DefId, DefIndex};
 use middle::cstore::InlinedItem;
 
 use syntax::ast::*;
+use syntax::ext::hygiene::Mark;
 use syntax::visit;
 use syntax::parse::token::{self, keywords};
 
@@ -31,7 +32,7 @@ pub struct DefCollector<'a> {
 }
 
 pub struct MacroInvocationData {
-    pub id: NodeId,
+    pub mark: Mark,
     pub def_index: DefIndex,
     pub const_integer: bool,
 }
@@ -126,7 +127,7 @@ impl<'a> DefCollector<'a> {
     fn visit_macro_invoc(&mut self, id: NodeId, const_integer: bool) {
         if let Some(ref mut visit) = self.visit_macro_invoc {
             visit(MacroInvocationData {
-                id: id,
+                mark: Mark::from_placeholder_id(id),
                 const_integer: const_integer,
                 def_index: self.parent_def.unwrap(),
             })

src/librustc_resolve/build_reduced_graph.rs

@@ -531,7 +531,7 @@ pub struct BuildReducedGraphVisitor<'a, 'b: 'a> {
 
 impl<'a, 'b> BuildReducedGraphVisitor<'a, 'b> {
     fn visit_invoc(&mut self, id: ast::NodeId) {
-        self.resolver.expansion_data.get_mut(&id.as_u32()).unwrap().module =
+        self.resolver.expansion_data.get_mut(&Mark::from_placeholder_id(id)).unwrap().module =
             self.resolver.current_module;
     }
 }

src/librustc_resolve/lib.rs

@@ -1084,7 +1084,7 @@ pub struct Resolver<'a> {
     macro_names: FnvHashSet<Name>,
 
     // Maps the `Mark` of an expansion to its containing module or block.
-    expansion_data: FnvHashMap<u32, macros::ExpansionData<'a>>,
+    expansion_data: FnvHashMap<Mark, macros::ExpansionData<'a>>,
 }
 
 pub struct ResolverArenas<'a> {
@@ -1202,7 +1202,7 @@ impl<'a> Resolver<'a> {
         DefCollector::new(&mut definitions).collect_root();
 
         let mut expansion_data = FnvHashMap();
-        expansion_data.insert(0, macros::ExpansionData::root(graph_root)); // Crate root expansion
+        expansion_data.insert(Mark::root(), macros::ExpansionData::root(graph_root));
 
         Resolver {
             session: session,

src/librustc_resolve/macros.rs

@@ -55,7 +55,7 @@ impl<'a> base::Resolver for Resolver<'a> {
     fn get_module_scope(&mut self, id: ast::NodeId) -> Mark {
         let mark = Mark::fresh();
         let module = self.module_map[&id];
-        self.expansion_data.insert(mark.as_u32(), ExpansionData {
+        self.expansion_data.insert(mark, ExpansionData {
             module: module,
             def_index: module.def_id().unwrap().index,
             const_integer: false,
@@ -65,7 +65,7 @@ impl<'a> base::Resolver for Resolver<'a> {
 
     fn visit_expansion(&mut self, mark: Mark, expansion: &Expansion) {
         self.collect_def_ids(mark, expansion);
-        self.current_module = self.expansion_data[&mark.as_u32()].module;
+        self.current_module = self.expansion_data[&mark].module;
         expansion.visit_with(&mut BuildReducedGraphVisitor { resolver: self });
     }
 
@@ -88,7 +88,7 @@ impl<'a> base::Resolver for Resolver<'a> {
             self.macro_names.insert(ident.name);
         }
 
-        let mut module = self.expansion_data[&scope.as_u32()].module;
+        let mut module = self.expansion_data[&scope].module;
         while module.macros_escape {
             module = module.parent.unwrap();
         }
@@ -104,7 +104,7 @@ impl<'a> base::Resolver for Resolver<'a> {
     fn find_attr_invoc(&mut self, attrs: &mut Vec<ast::Attribute>) -> Option<ast::Attribute> {
         for i in 0..attrs.len() {
             let name = intern(&attrs[i].name());
-            match self.expansion_data[&0].module.macros.borrow().get(&name) {
+            match self.expansion_data[&Mark::root()].module.macros.borrow().get(&name) {
                 Some(binding) => match *binding.ext {
                     MultiModifier(..) | MultiDecorator(..) | SyntaxExtension::AttrProcMacro(..) => {
                         return Some(attrs.remove(i))
@@ -132,7 +132,7 @@ impl<'a> base::Resolver for Resolver<'a> {
             InvocationKind::Attr { ref attr, .. } => (intern(&*attr.name()), attr.span),
         };
 
-        let mut module = self.expansion_data[&scope.as_u32()].module;
+        let mut module = self.expansion_data[&scope].module;
         loop {
             if let Some(binding) = module.macros.borrow().get(&name) {
                 return Some(binding.ext.clone());
@@ -168,9 +168,9 @@ impl<'a> Resolver<'a> {
 
     fn collect_def_ids(&mut self, mark: Mark, expansion: &Expansion) {
         let expansion_data = &mut self.expansion_data;
-        let ExpansionData { def_index, const_integer, module } = expansion_data[&mark.as_u32()];
+        let ExpansionData { def_index, const_integer, module } = expansion_data[&mark];
         let visit_macro_invoc = &mut |invoc: map::MacroInvocationData| {
-            expansion_data.entry(invoc.id.as_u32()).or_insert(ExpansionData {
+            expansion_data.entry(invoc.mark).or_insert(ExpansionData {
                 def_index: invoc.def_index,
                 const_integer: invoc.const_integer,
                 module: module,

src/libsyntax/ext/hygiene.rs

@@ -15,6 +15,7 @@
 //! and definition contexts*. J. Funct. Program. 22, 2 (March 2012), 181-216.
 //! DOI=10.1017/S0956796812000093 http://dx.doi.org/10.1017/S0956796812000093
 
+use ast::NodeId;
 use std::cell::RefCell;
 use std::collections::HashMap;
 use std::fmt;
@@ -46,6 +47,10 @@ impl Mark {
         Mark(0)
     }
 
+    pub fn from_placeholder_id(id: NodeId) -> Self {
+        Mark(id.as_u32())
+    }
+
     pub fn as_u32(&self) -> u32 {
         self.0
     }