Add `SymbolExportInfo`

This is currently a wrapper to `SymbolExportLevel` but it allows
later addition of extra information.

12 files changed, 75 insertions, 38 deletions

diff --git a/compiler/rustc_codegen_llvm/src/back/lto.rs b/compiler/rustc_codegen_llvm/src/back/lto.rs
index 0f5b1c08ec2..6bc242b46e0 100644
--- a/compiler/rustc_codegen_llvm/src/back/lto.rs
+++ b/compiler/rustc_codegen_llvm/src/back/lto.rs
@@ -16,7 +16,7 @@ use rustc_errors::{FatalError, Handler};
 use rustc_hir::def_id::LOCAL_CRATE;
 use rustc_middle::bug;
 use rustc_middle::dep_graph::WorkProduct;
-use rustc_middle::middle::exported_symbols::SymbolExportLevel;
+use rustc_middle::middle::exported_symbols::{SymbolExportInfo, SymbolExportLevel};
 use rustc_session::cgu_reuse_tracker::CguReuse;
 use rustc_session::config::{self, CrateType, Lto};
 use tracing::{debug, info};
@@ -55,8 +55,8 @@ fn prepare_lto(
         Lto::No => panic!("didn't request LTO but we're doing LTO"),
     };
 
-    let symbol_filter = &|&(ref name, level): &(String, SymbolExportLevel)| {
-        if level.is_below_threshold(export_threshold) {
+    let symbol_filter = &|&(ref name, info): &(String, SymbolExportInfo)| {
+        if info.level.is_below_threshold(export_threshold) {
             Some(CString::new(name.as_str()).unwrap())
         } else {
             None
diff --git a/compiler/rustc_codegen_ssa/src/back/linker.rs b/compiler/rustc_codegen_ssa/src/back/linker.rs
index 3a66bfafaf3..a90b8a62c62 100644
--- a/compiler/rustc_codegen_ssa/src/back/linker.rs
+++ b/compiler/rustc_codegen_ssa/src/back/linker.rs
@@ -1526,8 +1526,8 @@ pub(crate) fn exported_symbols(tcx: TyCtxt<'_>, crate_type: CrateType) -> Vec<St
     let mut symbols = Vec::new();
 
     let export_threshold = symbol_export::crates_export_threshold(&[crate_type]);
-    for &(symbol, level) in tcx.exported_symbols(LOCAL_CRATE).iter() {
-        if level.is_below_threshold(export_threshold) {
+    for &(symbol, info) in tcx.exported_symbols(LOCAL_CRATE).iter() {
+        if info.level.is_below_threshold(export_threshold) {
             symbols.push(symbol_export::symbol_name_for_instance_in_crate(
                 tcx,
                 symbol,
@@ -1544,8 +1544,8 @@ pub(crate) fn exported_symbols(tcx: TyCtxt<'_>, crate_type: CrateType) -> Vec<St
         // For each dependency that we are linking to statically ...
         if *dep_format == Linkage::Static {
             // ... we add its symbol list to our export list.
-            for &(symbol, level) in tcx.exported_symbols(cnum).iter() {
-                if !level.is_below_threshold(export_threshold) {
+            for &(symbol, info) in tcx.exported_symbols(cnum).iter() {
+                if !info.level.is_below_threshold(export_threshold) {
                     continue;
                 }
 
diff --git a/compiler/rustc_codegen_ssa/src/back/symbol_export.rs b/compiler/rustc_codegen_ssa/src/back/symbol_export.rs
index 765bd877db1..e14ebe3ae48 100644
--- a/compiler/rustc_codegen_ssa/src/back/symbol_export.rs
+++ b/compiler/rustc_codegen_ssa/src/back/symbol_export.rs
@@ -9,7 +9,7 @@ use rustc_hir::Node;
 use rustc_index::vec::IndexVec;
 use rustc_middle::middle::codegen_fn_attrs::CodegenFnAttrFlags;
 use rustc_middle::middle::exported_symbols::{
-    metadata_symbol_name, ExportedSymbol, SymbolExportLevel,
+    metadata_symbol_name, ExportedSymbol, SymbolExportInfo, SymbolExportLevel,
 };
 use rustc_middle::ty::query::{ExternProviders, Providers};
 use rustc_middle::ty::subst::{GenericArgKind, SubstsRef};
@@ -42,7 +42,7 @@ pub fn crates_export_threshold(crate_types: &[CrateType]) -> SymbolExportLevel {
     }
 }
 
-fn reachable_non_generics_provider(tcx: TyCtxt<'_>, cnum: CrateNum) -> DefIdMap<SymbolExportLevel> {
+fn reachable_non_generics_provider(tcx: TyCtxt<'_>, cnum: CrateNum) -> DefIdMap<SymbolExportInfo> {
     assert_eq!(cnum, LOCAL_CRATE);
 
     if !tcx.sess.opts.output_types.should_codegen() {
@@ -129,12 +129,17 @@ fn reachable_non_generics_provider(tcx: TyCtxt<'_>, cnum: CrateNum) -> DefIdMap<
                 tcx.symbol_name(Instance::mono(tcx, def_id.to_def_id())),
                 export_level
             );
-            (def_id.to_def_id(), export_level)
+            (def_id.to_def_id(), SymbolExportInfo {
+                level: export_level,
+            })
         })
         .collect();
 
     if let Some(id) = tcx.proc_macro_decls_static(()) {
-        reachable_non_generics.insert(id.to_def_id(), SymbolExportLevel::C);
+        reachable_non_generics.insert(
+            id.to_def_id(),
+            SymbolExportInfo { level: SymbolExportLevel::C },
+        );
     }
 
     reachable_non_generics
@@ -143,8 +148,8 @@ fn reachable_non_generics_provider(tcx: TyCtxt<'_>, cnum: CrateNum) -> DefIdMap<
 fn is_reachable_non_generic_provider_local(tcx: TyCtxt<'_>, def_id: DefId) -> bool {
     let export_threshold = threshold(tcx);
 
-    if let Some(&level) = tcx.reachable_non_generics(def_id.krate).get(&def_id) {
-        level.is_below_threshold(export_threshold)
+    if let Some(&info) = tcx.reachable_non_generics(def_id.krate).get(&def_id) {
+        info.level.is_below_threshold(export_threshold)
     } else {
         false
     }
@@ -157,7 +162,7 @@ fn is_reachable_non_generic_provider_extern(tcx: TyCtxt<'_>, def_id: DefId) -> b
 fn exported_symbols_provider_local<'tcx>(
     tcx: TyCtxt<'tcx>,
     cnum: CrateNum,
-) -> &'tcx [(ExportedSymbol<'tcx>, SymbolExportLevel)] {
+) -> &'tcx [(ExportedSymbol<'tcx>, SymbolExportInfo)] {
     assert_eq!(cnum, LOCAL_CRATE);
 
     if !tcx.sess.opts.output_types.should_codegen() {
@@ -167,13 +172,16 @@ fn exported_symbols_provider_local<'tcx>(
     let mut symbols: Vec<_> = tcx
         .reachable_non_generics(LOCAL_CRATE)
         .iter()
-        .map(|(&def_id, &level)| (ExportedSymbol::NonGeneric(def_id), level))
+        .map(|(&def_id, &info)| (ExportedSymbol::NonGeneric(def_id), info))
         .collect();
 
     if tcx.entry_fn(()).is_some() {
         let exported_symbol = ExportedSymbol::NoDefId(SymbolName::new(tcx, "main"));
 
-        symbols.push((exported_symbol, SymbolExportLevel::C));
+        symbols.push((
+            exported_symbol,
+            SymbolExportInfo { level: SymbolExportLevel::C },
+        ));
     }
 
     if tcx.allocator_kind(()).is_some() {
@@ -181,7 +189,10 @@ fn exported_symbols_provider_local<'tcx>(
             let symbol_name = format!("__rust_{}", method.name);
             let exported_symbol = ExportedSymbol::NoDefId(SymbolName::new(tcx, &symbol_name));
 
-            symbols.push((exported_symbol, SymbolExportLevel::Rust));
+            symbols.push((
+                exported_symbol,
+                SymbolExportInfo { level: SymbolExportLevel::Rust },
+            ));
         }
     }
 
@@ -194,7 +205,10 @@ fn exported_symbols_provider_local<'tcx>(
 
         symbols.extend(PROFILER_WEAK_SYMBOLS.iter().map(|sym| {
             let exported_symbol = ExportedSymbol::NoDefId(SymbolName::new(tcx, sym));
-            (exported_symbol, SymbolExportLevel::C)
+            (
+                exported_symbol,
+                SymbolExportInfo { level: SymbolExportLevel::C },
+            )
         }));
     }
 
@@ -204,7 +218,10 @@ fn exported_symbols_provider_local<'tcx>(
 
         symbols.extend(MSAN_WEAK_SYMBOLS.iter().map(|sym| {
             let exported_symbol = ExportedSymbol::NoDefId(SymbolName::new(tcx, sym));
-            (exported_symbol, SymbolExportLevel::C)
+            (
+                exported_symbol,
+                SymbolExportInfo { level: SymbolExportLevel::C },
+            )
         }));
     }
 
@@ -212,7 +229,10 @@ fn exported_symbols_provider_local<'tcx>(
         let symbol_name = metadata_symbol_name(tcx);
         let exported_symbol = ExportedSymbol::NoDefId(SymbolName::new(tcx, &symbol_name));
 
-        symbols.push((exported_symbol, SymbolExportLevel::Rust));
+        symbols.push((
+            exported_symbol,
+            SymbolExportInfo { level: SymbolExportLevel::Rust },
+        ));
     }
 
     if tcx.sess.opts.share_generics() && tcx.local_crate_exports_generics() {
@@ -245,7 +265,12 @@ fn exported_symbols_provider_local<'tcx>(
                 MonoItem::Fn(Instance { def: InstanceDef::Item(def), substs }) => {
                     if substs.non_erasable_generics().next().is_some() {
                         let symbol = ExportedSymbol::Generic(def.did, substs);
-                        symbols.push((symbol, SymbolExportLevel::Rust));
+                        symbols.push((
+                            symbol,
+                            SymbolExportInfo {
+                                level: SymbolExportLevel::Rust,
+                            },
+                        ));
                     }
                 }
                 MonoItem::Fn(Instance { def: InstanceDef::DropGlue(_, Some(ty)), substs }) => {
@@ -254,7 +279,12 @@ fn exported_symbols_provider_local<'tcx>(
                         substs.non_erasable_generics().next(),
                         Some(GenericArgKind::Type(ty))
                     );
-                    symbols.push((ExportedSymbol::DropGlue(ty), SymbolExportLevel::Rust));
+                    symbols.push((
+                        ExportedSymbol::DropGlue(ty),
+                        SymbolExportInfo {
+                            level: SymbolExportLevel::Rust,
+                        },
+                    ));
                 }
                 _ => {
                     // Any other symbols don't qualify for sharing
diff --git a/compiler/rustc_codegen_ssa/src/back/write.rs b/compiler/rustc_codegen_ssa/src/back/write.rs
index d4eaf6389df..7a6e9bfd2b7 100644
--- a/compiler/rustc_codegen_ssa/src/back/write.rs
+++ b/compiler/rustc_codegen_ssa/src/back/write.rs
@@ -23,7 +23,7 @@ use rustc_incremental::{
 };
 use rustc_metadata::EncodedMetadata;
 use rustc_middle::dep_graph::{WorkProduct, WorkProductId};
-use rustc_middle::middle::exported_symbols::SymbolExportLevel;
+use rustc_middle::middle::exported_symbols::SymbolExportInfo;
 use rustc_middle::ty::TyCtxt;
 use rustc_session::cgu_reuse_tracker::CguReuseTracker;
 use rustc_session::config::{self, CrateType, Lto, OutputFilenames, OutputType};
@@ -304,7 +304,7 @@ pub type TargetMachineFactoryFn<B> = Arc<
         + Sync,
 >;
 
-pub type ExportedSymbols = FxHashMap<CrateNum, Arc<Vec<(String, SymbolExportLevel)>>>;
+pub type ExportedSymbols = FxHashMap<CrateNum, Arc<Vec<(String, SymbolExportInfo)>>>;
 
 /// Additional resources used by optimize_and_codegen (not module specific)
 #[derive(Clone)]
diff --git a/compiler/rustc_metadata/src/rmeta/decoder.rs b/compiler/rustc_metadata/src/rmeta/decoder.rs
index 046322a42d8..d7a4547bcc6 100644
--- a/compiler/rustc_metadata/src/rmeta/decoder.rs
+++ b/compiler/rustc_metadata/src/rmeta/decoder.rs
@@ -22,7 +22,7 @@ use rustc_hir::lang_items;
 use rustc_index::vec::{Idx, IndexVec};
 use rustc_middle::arena::ArenaAllocatable;
 use rustc_middle::metadata::ModChild;
-use rustc_middle::middle::exported_symbols::{ExportedSymbol, SymbolExportLevel};
+use rustc_middle::middle::exported_symbols::{ExportedSymbol, SymbolExportInfo};
 use rustc_middle::middle::stability::DeprecationEntry;
 use rustc_middle::mir::interpret::{AllocDecodingSession, AllocDecodingState};
 use rustc_middle::thir;
@@ -1405,7 +1405,7 @@ impl<'a, 'tcx> CrateMetadataRef<'a> {
     fn exported_symbols(
         self,
         tcx: TyCtxt<'tcx>,
-    ) -> &'tcx [(ExportedSymbol<'tcx>, SymbolExportLevel)] {
+    ) -> &'tcx [(ExportedSymbol<'tcx>, SymbolExportInfo)] {
         tcx.arena.alloc_from_iter(self.root.exported_symbols.decode((self, tcx)))
     }
 
diff --git a/compiler/rustc_metadata/src/rmeta/decoder/cstore_impl.rs b/compiler/rustc_metadata/src/rmeta/decoder/cstore_impl.rs
index cd3a1d72d41..1a7c458b6a2 100644
--- a/compiler/rustc_metadata/src/rmeta/decoder/cstore_impl.rs
+++ b/compiler/rustc_metadata/src/rmeta/decoder/cstore_impl.rs
@@ -188,9 +188,9 @@ provide! { <'tcx> tcx, def_id, other, cdata,
         let reachable_non_generics = tcx
             .exported_symbols(cdata.cnum)
             .iter()
-            .filter_map(|&(exported_symbol, export_level)| {
+            .filter_map(|&(exported_symbol, export_info)| {
                 if let ExportedSymbol::NonGeneric(def_id) = exported_symbol {
-                    Some((def_id, export_level))
+                    Some((def_id, export_info))
                 } else {
                     None
                 }
diff --git a/compiler/rustc_metadata/src/rmeta/encoder.rs b/compiler/rustc_metadata/src/rmeta/encoder.rs
index 6c758b8e5b6..9c94dca9ecd 100644
--- a/compiler/rustc_metadata/src/rmeta/encoder.rs
+++ b/compiler/rustc_metadata/src/rmeta/encoder.rs
@@ -21,7 +21,7 @@ use rustc_index::vec::Idx;
 use rustc_middle::hir::nested_filter;
 use rustc_middle::middle::dependency_format::Linkage;
 use rustc_middle::middle::exported_symbols::{
-    metadata_symbol_name, ExportedSymbol, SymbolExportLevel,
+    metadata_symbol_name, ExportedSymbol, SymbolExportInfo,
 };
 use rustc_middle::mir::interpret;
 use rustc_middle::thir;
@@ -1844,8 +1844,8 @@ impl<'a, 'tcx> EncodeContext<'a, 'tcx> {
     // definition (as that's not defined in this crate).
     fn encode_exported_symbols(
         &mut self,
-        exported_symbols: &[(ExportedSymbol<'tcx>, SymbolExportLevel)],
-    ) -> Lazy<[(ExportedSymbol<'tcx>, SymbolExportLevel)]> {
+        exported_symbols: &[(ExportedSymbol<'tcx>, SymbolExportInfo)],
+    ) -> Lazy<[(ExportedSymbol<'tcx>, SymbolExportInfo)]> {
         empty_proc_macro!(self);
         // The metadata symbol name is special. It should not show up in
         // downstream crates.
diff --git a/compiler/rustc_metadata/src/rmeta/mod.rs b/compiler/rustc_metadata/src/rmeta/mod.rs
index 15e8693d712..c0b7a787b80 100644
--- a/compiler/rustc_metadata/src/rmeta/mod.rs
+++ b/compiler/rustc_metadata/src/rmeta/mod.rs
@@ -13,7 +13,7 @@ use rustc_hir::definitions::DefKey;
 use rustc_hir::lang_items;
 use rustc_index::{bit_set::FiniteBitSet, vec::IndexVec};
 use rustc_middle::metadata::ModChild;
-use rustc_middle::middle::exported_symbols::{ExportedSymbol, SymbolExportLevel};
+use rustc_middle::middle::exported_symbols::{ExportedSymbol, SymbolExportInfo};
 use rustc_middle::mir;
 use rustc_middle::thir;
 use rustc_middle::ty::fast_reject::SimplifiedType;
@@ -218,7 +218,7 @@ crate struct CrateRoot<'tcx> {
 
     tables: LazyTables<'tcx>,
 
-    exported_symbols: Lazy!([(ExportedSymbol<'tcx>, SymbolExportLevel)]),
+    exported_symbols: Lazy!([(ExportedSymbol<'tcx>, SymbolExportInfo)]),
 
     syntax_contexts: SyntaxContextTable,
     expn_data: ExpnDataTable,
diff --git a/compiler/rustc_middle/src/middle/exported_symbols.rs b/compiler/rustc_middle/src/middle/exported_symbols.rs
index 5ea78e087f8..a605e6dfdc1 100644
--- a/compiler/rustc_middle/src/middle/exported_symbols.rs
+++ b/compiler/rustc_middle/src/middle/exported_symbols.rs
@@ -21,6 +21,13 @@ impl SymbolExportLevel {
     }
 }
 
+/// The `SymbolExportInfo` of a symbols specifies symbol-related information
+/// that is relevant to code generation and linking.
+#[derive(Eq, PartialEq, Debug, Copy, Clone, TyEncodable, TyDecodable, HashStable)]
+pub struct SymbolExportInfo {
+    pub level: SymbolExportLevel,
+}
+
 #[derive(Eq, PartialEq, Debug, Copy, Clone, TyEncodable, TyDecodable, HashStable)]
 pub enum ExportedSymbol<'tcx> {
     NonGeneric(DefId),
diff --git a/compiler/rustc_middle/src/query/mod.rs b/compiler/rustc_middle/src/query/mod.rs
index 89761bf4e27..97f1d96404b 100644
--- a/compiler/rustc_middle/src/query/mod.rs
+++ b/compiler/rustc_middle/src/query/mod.rs
@@ -1355,7 +1355,7 @@ rustc_queries! {
     // Does not include external symbols that don't have a corresponding DefId,
     // like the compiler-generated `main` function and so on.
     query reachable_non_generics(_: CrateNum)
-        -> DefIdMap<SymbolExportLevel> {
+        -> DefIdMap<SymbolExportInfo> {
         storage(ArenaCacheSelector<'tcx>)
         desc { "looking up the exported symbols of a crate" }
         separate_provide_extern
@@ -1672,7 +1672,7 @@ rustc_queries! {
     ///   correspond to a publicly visible symbol in `cnum` machine code.
     /// - The `exported_symbols` sets of different crates do not intersect.
     query exported_symbols(_: CrateNum)
-        -> &'tcx [(ExportedSymbol<'tcx>, SymbolExportLevel)] {
+        -> &'tcx [(ExportedSymbol<'tcx>, SymbolExportInfo)] {
         desc { "exported_symbols" }
         separate_provide_extern
     }
diff --git a/compiler/rustc_middle/src/ty/query.rs b/compiler/rustc_middle/src/ty/query.rs
index 9e48c569c25..6ff061a820e 100644
--- a/compiler/rustc_middle/src/ty/query.rs
+++ b/compiler/rustc_middle/src/ty/query.rs
@@ -3,7 +3,7 @@ use crate::infer::canonical::{self, Canonical};
 use crate::lint::LintLevelMap;
 use crate::metadata::ModChild;
 use crate::middle::codegen_fn_attrs::CodegenFnAttrs;
-use crate::middle::exported_symbols::{ExportedSymbol, SymbolExportLevel};
+use crate::middle::exported_symbols::{ExportedSymbol, SymbolExportInfo};
 use crate::middle::lib_features::LibFeatures;
 use crate::middle::privacy::AccessLevels;
 use crate::middle::region;
diff --git a/compiler/rustc_monomorphize/src/partitioning/default.rs b/compiler/rustc_monomorphize/src/partitioning/default.rs
index c4ffb19f87a..02f3efa695c 100644
--- a/compiler/rustc_monomorphize/src/partitioning/default.rs
+++ b/compiler/rustc_monomorphize/src/partitioning/default.rs
@@ -5,7 +5,7 @@ use rustc_hir::def::DefKind;
 use rustc_hir::def_id::{DefId, CRATE_DEF_INDEX, LOCAL_CRATE};
 use rustc_hir::definitions::DefPathDataName;
 use rustc_middle::middle::codegen_fn_attrs::CodegenFnAttrFlags;
-use rustc_middle::middle::exported_symbols::SymbolExportLevel;
+use rustc_middle::middle::exported_symbols::{SymbolExportInfo, SymbolExportLevel};
 use rustc_middle::mir::mono::{CodegenUnit, CodegenUnitNameBuilder, Linkage, Visibility};
 use rustc_middle::mir::mono::{InstantiationMode, MonoItem};
 use rustc_middle::ty::print::characteristic_def_id_of_type;
@@ -554,7 +554,7 @@ fn default_visibility(tcx: TyCtxt<'_>, id: DefId, is_generic: bool) -> Visibilit
     // C-export level items remain at `Default`, all other internal
     // items become `Hidden`.
     match tcx.reachable_non_generics(id.krate).get(&id) {
-        Some(SymbolExportLevel::C) => Visibility::Default,
+        Some(SymbolExportInfo { level: SymbolExportLevel::C, .. }) => Visibility::Default,
         _ => Visibility::Hidden,
     }
 }