From 0634aedbb7a1fba46a7991527b9d5c4517fb6924 Mon Sep 17 00:00:00 2001
From: bjorn3 <17426603+bjorn3@users.noreply.github.com>
Date: Wed, 27 Mar 2024 20:29:50 +0000
Subject: [PATCH] Implement debug_type for tuples

---
 src/debuginfo/types.rs | 47 +++++++++++++++++++++++++++++++++++++++++-
 1 file changed, 46 insertions(+), 1 deletion(-)

diff --git a/src/debuginfo/types.rs b/src/debuginfo/types.rs
index 7e5fafdd544..7baf0a3868d 100644
--- a/src/debuginfo/types.rs
+++ b/src/debuginfo/types.rs
@@ -56,7 +56,7 @@ pub(crate) fn debug_type<'tcx>(
             // ty::FnDef(..) | ty::FnPtr(..)
             // ty::Closure(..)
             // ty::Adt(def, ..)
-            // ty::Tuple(_)
+            ty::Tuple(components) => self.tuple_type(tcx, type_dbg, ty, *components),
             // ty::Param(_)
             // FIXME implement remaining types and add unreachable!() to the fallback branch
             _ => self.placeholder_for_type(tcx, type_dbg, ty),
@@ -144,6 +144,51 @@ fn pointer_type<'tcx>(
         }
     }
 
+    fn tuple_type<'tcx>(
+        &mut self,
+        tcx: TyCtxt<'tcx>,
+        type_dbg: &mut TypeDebugContext<'tcx>,
+        tuple_type: Ty<'tcx>,
+        components: &'tcx [Ty<'tcx>],
+    ) -> UnitEntryId {
+        let components = components
+            .into_iter()
+            .map(|&ty| (ty, self.debug_type(tcx, type_dbg, ty)))
+            .collect::<Vec<_>>();
+
+        return_if_type_created_in_meantime!(type_dbg, tuple_type);
+
+        let name = type_names::compute_debuginfo_type_name(tcx, tuple_type, false);
+        let layout = RevealAllLayoutCx(tcx).layout_of(tuple_type);
+
+        let tuple_type_id =
+            self.dwarf.unit.add(self.dwarf.unit.root(), gimli::DW_TAG_structure_type);
+        let tuple_entry = self.dwarf.unit.get_mut(tuple_type_id);
+        tuple_entry.set(gimli::DW_AT_name, AttributeValue::StringRef(self.dwarf.strings.add(name)));
+        tuple_entry.set(gimli::DW_AT_byte_size, AttributeValue::Udata(layout.size.bytes()));
+        tuple_entry.set(gimli::DW_AT_alignment, AttributeValue::Udata(layout.align.pref.bytes()));
+
+        for (i, (ty, dw_ty)) in components.into_iter().enumerate() {
+            let member_id = self.dwarf.unit.add(tuple_type_id, gimli::DW_TAG_member);
+            let member_entry = self.dwarf.unit.get_mut(member_id);
+            member_entry.set(
+                gimli::DW_AT_name,
+                AttributeValue::StringRef(self.dwarf.strings.add(format!("__{i}"))),
+            );
+            member_entry.set(gimli::DW_AT_type, AttributeValue::UnitRef(dw_ty));
+            member_entry.set(
+                gimli::DW_AT_alignment,
+                AttributeValue::Udata(RevealAllLayoutCx(tcx).layout_of(ty).align.pref.bytes()),
+            );
+            member_entry.set(
+                gimli::DW_AT_data_member_location,
+                AttributeValue::Udata(layout.fields.offset(i).bytes()),
+            );
+        }
+
+        tuple_type_id
+    }
+
     fn placeholder_for_type<'tcx>(
         &mut self,
         tcx: TyCtxt<'tcx>,