Always calculate glob map but only for glob uses

Previously calculating glob map was *opt-in*, however it did record
node id -> ident use for every use directive. This aims to see if we
can unconditionally calculate the glob map and not regress performance.

9 files changed, 11 insertions, 41 deletions

diff --git a/src/librustc/ty/mod.rs b/src/librustc/ty/mod.rs
index cfd99948e43..26b4735d926 100644
--- a/src/librustc/ty/mod.rs
+++ b/src/librustc/ty/mod.rs
@@ -122,7 +122,7 @@ mod sty;
 /// *on-demand* infrastructure.
 #[derive(Clone)]
 pub struct CrateAnalysis {
-    pub glob_map: Option<hir::GlobMap>,
+    pub glob_map: hir::GlobMap,
 }
 
 #[derive(Clone)]
diff --git a/src/librustc_driver/driver.rs b/src/librustc_driver/driver.rs
index bfff592a5dd..e026909d127 100644
--- a/src/librustc_driver/driver.rs
+++ b/src/librustc_driver/driver.rs
@@ -26,7 +26,7 @@ use rustc_passes::{self, ast_validation, hir_stats, loops, rvalue_promotion};
 use rustc_plugin as plugin;
 use rustc_plugin::registry::Registry;
 use rustc_privacy;
-use rustc_resolve::{MakeGlobMap, Resolver, ResolverArenas};
+use rustc_resolve::{Resolver, ResolverArenas};
 use rustc_traits;
 use rustc_typeck as typeck;
 use syntax::{self, ast, attr, diagnostics, visit};
@@ -179,7 +179,6 @@ pub fn compile_input(
                 registry,
                 &crate_name,
                 addl_plugins,
-                control.make_glob_map,
                 |expanded_crate| {
                     let mut state = CompileState::state_after_expand(
                         input,
@@ -394,7 +393,6 @@ pub struct CompileController<'a> {
 
     // FIXME we probably want to group the below options together and offer a
     // better API, rather than this ad-hoc approach.
-    pub make_glob_map: MakeGlobMap,
     // Whether the compiler should keep the ast beyond parsing.
     pub keep_ast: bool,
     // -Zcontinue-parse-after-error
@@ -417,7 +415,6 @@ impl<'a> CompileController<'a> {
             after_hir_lowering: PhaseController::basic(),
             after_analysis: PhaseController::basic(),
             compilation_done: PhaseController::basic(),
-            make_glob_map: MakeGlobMap::No,
             keep_ast: false,
             continue_parse_after_error: false,
             provide: box |_| {},
@@ -739,7 +736,6 @@ pub fn phase_2_configure_and_expand<F>(
     registry: Option<Registry>,
     crate_name: &str,
     addl_plugins: Option<Vec<String>>,
-    make_glob_map: MakeGlobMap,
     after_expand: F,
 ) -> Result<ExpansionResult, CompileIncomplete>
 where
@@ -759,7 +755,6 @@ where
         registry,
         crate_name,
         addl_plugins,
-        make_glob_map,
         &resolver_arenas,
         &mut crate_loader,
         after_expand,
@@ -785,11 +780,7 @@ where
             },
 
             analysis: ty::CrateAnalysis {
-                glob_map: if resolver.make_glob_map {
-                    Some(resolver.glob_map)
-                } else {
-                    None
-                },
+                glob_map: resolver.glob_map
             },
         }),
         Err(x) => Err(x),
@@ -805,7 +796,6 @@ pub fn phase_2_configure_and_expand_inner<'a, F>(
     registry: Option<Registry>,
     crate_name: &str,
     addl_plugins: Option<Vec<String>>,
-    make_glob_map: MakeGlobMap,
     resolver_arenas: &'a ResolverArenas<'a>,
     crate_loader: &'a mut CrateLoader<'a>,
     after_expand: F,
@@ -937,7 +927,6 @@ where
         cstore,
         &krate,
         crate_name,
-        make_glob_map,
         crate_loader,
         &resolver_arenas,
     );
diff --git a/src/librustc_driver/lib.rs b/src/librustc_driver/lib.rs
index 889e1ec3b98..010ac28cdc9 100644
--- a/src/librustc_driver/lib.rs
+++ b/src/librustc_driver/lib.rs
@@ -57,7 +57,6 @@ extern crate syntax_pos;
 use driver::CompileController;
 use pretty::{PpMode, UserIdentifiedItem};
 
-use rustc_resolve as resolve;
 use rustc_save_analysis as save;
 use rustc_save_analysis::DumpHandler;
 use rustc_data_structures::sync::{self, Lrc, Ordering::SeqCst};
@@ -950,7 +949,6 @@ pub fn enable_save_analysis(control: &mut CompileController) {
         });
     };
     control.after_analysis.run_callback_on_error = true;
-    control.make_glob_map = resolve::MakeGlobMap::Yes;
 }
 
 impl RustcDefaultCalls {
diff --git a/src/librustc_driver/test.rs b/src/librustc_driver/test.rs
index 9c027f110eb..afcf08632a4 100644
--- a/src/librustc_driver/test.rs
+++ b/src/librustc_driver/test.rs
@@ -18,7 +18,6 @@ use rustc::ty::{self, Ty, TyCtxt, TypeFoldable};
 use rustc_data_structures::sync::{self, Lrc};
 use rustc_lint;
 use rustc_metadata::cstore::CStore;
-use rustc_resolve::MakeGlobMap;
 use rustc_target::spec::abi::Abi;
 use syntax;
 use syntax::ast;
@@ -134,7 +133,6 @@ fn test_env_with_pool<F>(
             None,
             "test",
             None,
-            MakeGlobMap::No,
             |_| Ok(()),
         ).expect("phase 2 aborted")
     };
diff --git a/src/librustc_resolve/lib.rs b/src/librustc_resolve/lib.rs
index 7c05913467c..797837c0e84 100644
--- a/src/librustc_resolve/lib.rs
+++ b/src/librustc_resolve/lib.rs
@@ -1536,9 +1536,7 @@ pub struct Resolver<'a> {
     extern_module_map: FxHashMap<(DefId, bool /* MacrosOnly? */), Module<'a>>,
     binding_parent_modules: FxHashMap<PtrKey<'a, NameBinding<'a>>, Module<'a>>,
 
-    pub make_glob_map: bool,
-    /// Maps imports to the names of items actually imported (this actually maps
-    /// all imports, but only glob imports are actually interesting).
+    /// Maps glob imports to the names of items actually imported.
     pub glob_map: GlobMap,
 
     used_imports: FxHashSet<(NodeId, Namespace)>,
@@ -1785,7 +1783,6 @@ impl<'a> Resolver<'a> {
                cstore: &'a CStore,
                krate: &Crate,
                crate_name: &str,
-               make_glob_map: MakeGlobMap,
                crate_loader: &'a mut CrateLoader<'a>,
                arenas: &'a ResolverArenas<'a>)
                -> Resolver<'a> {
@@ -1869,7 +1866,6 @@ impl<'a> Resolver<'a> {
             extern_module_map: FxHashMap::default(),
             binding_parent_modules: FxHashMap::default(),
 
-            make_glob_map: make_glob_map == MakeGlobMap::Yes,
             glob_map: Default::default(),
 
             used_imports: FxHashSet::default(),
@@ -1979,14 +1975,15 @@ impl<'a> Resolver<'a> {
             used.set(true);
             directive.used.set(true);
             self.used_imports.insert((directive.id, ns));
-            self.add_to_glob_map(directive.id, ident);
+            self.add_to_glob_map(&directive, ident);
             self.record_use(ident, ns, binding, false);
         }
     }
 
-    fn add_to_glob_map(&mut self, id: NodeId, ident: Ident) {
-        if self.make_glob_map {
-            self.glob_map.entry(id).or_default().insert(ident.name);
+    #[inline]
+    fn add_to_glob_map(&mut self, directive: &ImportDirective<'_>, ident: Ident) {
+        if directive.is_glob() {
+            self.glob_map.entry(directive.id).or_default().insert(ident.name);
         }
     }
 
@@ -4551,7 +4548,7 @@ impl<'a> Resolver<'a> {
                 let import_id = match binding.kind {
                     NameBindingKind::Import { directive, .. } => {
                         self.maybe_unused_trait_imports.insert(directive.id);
-                        self.add_to_glob_map(directive.id, trait_name);
+                        self.add_to_glob_map(&directive, trait_name);
                         Some(directive.id)
                     }
                     _ => None,
@@ -5255,12 +5252,6 @@ fn err_path_resolution() -> PathResolution {
     PathResolution::new(Def::Err)
 }
 
-#[derive(PartialEq,Copy, Clone)]
-pub enum MakeGlobMap {
-    Yes,
-    No,
-}
-
 #[derive(Copy, Clone, Debug)]
 enum CrateLint {
     /// Do not issue the lint
diff --git a/src/librustc_save_analysis/dump_visitor.rs b/src/librustc_save_analysis/dump_visitor.rs
index 89153730917..52be67fb512 100644
--- a/src/librustc_save_analysis/dump_visitor.rs
+++ b/src/librustc_save_analysis/dump_visitor.rs
@@ -1239,7 +1239,6 @@ impl<'l, 'tcx: 'l, 'll, O: DumpOutput + 'll> DumpVisitor<'l, 'tcx, 'll, O> {
 
                 // Make a comma-separated list of names of imported modules.
                 let glob_map = &self.save_ctxt.analysis.glob_map;
-                let glob_map = glob_map.as_ref().unwrap();
                 let names = if glob_map.contains_key(&id) {
                     glob_map.get(&id).unwrap().iter().map(|n| n.to_string()).collect()
                 } else {
diff --git a/src/librustc_save_analysis/lib.rs b/src/librustc_save_analysis/lib.rs
index d5b3070372b..4b0fb686ba5 100644
--- a/src/librustc_save_analysis/lib.rs
+++ b/src/librustc_save_analysis/lib.rs
@@ -1122,8 +1122,6 @@ pub fn process_crate<'l, 'tcx, H: SaveHandler>(
     mut handler: H,
 ) {
     tcx.dep_graph.with_ignore(|| {
-        assert!(analysis.glob_map.is_some());
-
         info!("Dumping crate {}", cratename);
 
         let save_ctxt = SaveContext {
diff --git a/src/librustdoc/core.rs b/src/librustdoc/core.rs
index 8bb0dc9daa6..78dbf41bf21 100644
--- a/src/librustdoc/core.rs
+++ b/src/librustdoc/core.rs
@@ -451,7 +451,6 @@ pub fn run_core(options: RustdocOptions) -> (clean::Crate, RenderInfo, RenderOpt
                                                         None,
                                                         &name,
                                                         None,
-                                                        resolve::MakeGlobMap::No,
                                                         &resolver_arenas,
                                                         &mut crate_loader,
                                                         |_| Ok(()));
@@ -476,7 +475,7 @@ pub fn run_core(options: RustdocOptions) -> (clean::Crate, RenderInfo, RenderOpt
             }).collect(),
         };
         let analysis = ty::CrateAnalysis {
-            glob_map: if resolver.make_glob_map { Some(resolver.glob_map.clone()) } else { None },
+            glob_map: resolver.glob_map.clone(),
         };
 
         let mut arenas = AllArenas::new();
diff --git a/src/librustdoc/test.rs b/src/librustdoc/test.rs
index 1f19fa2e7f5..af47c7d5e8b 100644
--- a/src/librustdoc/test.rs
+++ b/src/librustdoc/test.rs
@@ -6,7 +6,6 @@ use rustc_driver::{self, driver, target_features, Compilation};
 use rustc_driver::driver::phase_2_configure_and_expand;
 use rustc_metadata::cstore::CStore;
 use rustc_metadata::dynamic_lib::DynamicLibrary;
-use rustc_resolve::MakeGlobMap;
 use rustc::hir;
 use rustc::hir::intravisit;
 use rustc::session::{self, CompileIncomplete, config};
@@ -100,7 +99,6 @@ pub fn run(mut options: Options) -> isize {
                 None,
                 "rustdoc-test",
                 None,
-                MakeGlobMap::No,
                 |_| Ok(()),
             ).expect("phase_2_configure_and_expand aborted in rustdoc!")
         };