From 30ae64e51fae5bfbe93199dd1795207444d9931f Mon Sep 17 00:00:00 2001
From: Camille GILLOT <gillot.camille@gmail.com>
Date: Sun, 3 Jul 2022 17:49:06 +0200
Subject: [PATCH] Create a table for fn_has_self_parameter.

---
 compiler/rustc_metadata/src/rmeta/decoder.rs | 14 ++++++--------
 compiler/rustc_metadata/src/rmeta/encoder.rs | 14 ++++++++------
 compiler/rustc_metadata/src/rmeta/mod.rs     |  4 +++-
 3 files changed, 17 insertions(+), 15 deletions(-)

diff --git a/compiler/rustc_metadata/src/rmeta/decoder.rs b/compiler/rustc_metadata/src/rmeta/decoder.rs
index a29e1edc641d..b62aa95b254b 100644
--- a/compiler/rustc_metadata/src/rmeta/decoder.rs
+++ b/compiler/rustc_metadata/src/rmeta/decoder.rs
@@ -1115,10 +1115,7 @@ impl<'a, 'tcx> CrateMetadataRef<'a> {
     }
 
     fn get_fn_has_self_parameter(self, id: DefIndex) -> bool {
-        match self.kind(id) {
-            EntryKind::AssocFn { has_self } => has_self,
-            _ => false,
-        }
+        self.root.tables.fn_has_self_parameter.get(self, id).is_some()
     }
 
     fn get_associated_item_def_ids(
@@ -1138,12 +1135,13 @@ impl<'a, 'tcx> CrateMetadataRef<'a> {
     fn get_associated_item(self, id: DefIndex) -> ty::AssocItem {
         let name = self.item_name(id);
 
-        let (kind, has_self) = match self.kind(id) {
-            EntryKind::AssocConst => (ty::AssocKind::Const, false),
-            EntryKind::AssocFn { has_self } => (ty::AssocKind::Fn, has_self),
-            EntryKind::AssocType => (ty::AssocKind::Type, false),
+        let kind = match self.kind(id) {
+            EntryKind::AssocConst => ty::AssocKind::Const,
+            EntryKind::AssocFn => ty::AssocKind::Fn,
+            EntryKind::AssocType => ty::AssocKind::Type,
             _ => bug!("cannot get associated-item of `{:?}`", self.def_key(id)),
         };
+        let has_self = self.get_fn_has_self_parameter(id);
         let container = self.root.tables.assoc_container.get(self, id).unwrap();
 
         ty::AssocItem {
diff --git a/compiler/rustc_metadata/src/rmeta/encoder.rs b/compiler/rustc_metadata/src/rmeta/encoder.rs
index fdc25270e971..65f93ce1a25d 100644
--- a/compiler/rustc_metadata/src/rmeta/encoder.rs
+++ b/compiler/rustc_metadata/src/rmeta/encoder.rs
@@ -1344,9 +1344,10 @@ impl<'a, 'tcx> EncodeContext<'a, 'tcx> {
                 };
                 self.tables.asyncness.set(def_id.index, m_sig.header.asyncness);
                 self.tables.constness.set(def_id.index, hir::Constness::NotConst);
-                record!(self.tables.kind[def_id] <- EntryKind::AssocFn {
-                    has_self: trait_item.fn_has_self_parameter,
-                });
+                if trait_item.fn_has_self_parameter {
+                    self.tables.fn_has_self_parameter.set(def_id.index, ());
+                }
+                record!(self.tables.kind[def_id] <- EntryKind::AssocFn );
             }
             ty::AssocKind::Type => {
                 self.encode_explicit_item_bounds(def_id);
@@ -1382,9 +1383,10 @@ impl<'a, 'tcx> EncodeContext<'a, 'tcx> {
                     hir::Constness::NotConst
                 };
                 self.tables.constness.set(def_id.index, constness);
-                record!(self.tables.kind[def_id] <- EntryKind::AssocFn {
-                    has_self: impl_item.fn_has_self_parameter,
-                });
+                if impl_item.fn_has_self_parameter {
+                    self.tables.fn_has_self_parameter.set(def_id.index, ());
+                }
+                record!(self.tables.kind[def_id] <- EntryKind::AssocFn);
             }
             ty::AssocKind::Type => {
                 record!(self.tables.kind[def_id] <- EntryKind::AssocType);
diff --git a/compiler/rustc_metadata/src/rmeta/mod.rs b/compiler/rustc_metadata/src/rmeta/mod.rs
index 0367f244c000..f32fed6ec476 100644
--- a/compiler/rustc_metadata/src/rmeta/mod.rs
+++ b/compiler/rustc_metadata/src/rmeta/mod.rs
@@ -397,6 +397,8 @@ define_tables! {
     assoc_container: Table<DefIndex, ty::AssocItemContainer>,
     macro_definition: Table<DefIndex, LazyValue<ast::MacroDef>>,
     proc_macro: Table<DefIndex, MacroKind>,
+    // Slot is full when there is a self parameter.
+    fn_has_self_parameter: Table<DefIndex, ()>,
 }
 
 #[derive(Copy, Clone, MetadataEncodable, MetadataDecodable)]
@@ -426,7 +428,7 @@ enum EntryKind {
     Generator,
     Trait,
     Impl,
-    AssocFn { has_self: bool },
+    AssocFn,
     AssocType,
     AssocConst,
     TraitAlias,