Add `SourceScope::inlined_instance`

2 files changed, 18 insertions, 5 deletions

diff --git a/compiler/rustc_codegen_ssa/src/mir/coverageinfo.rs b/compiler/rustc_codegen_ssa/src/mir/coverageinfo.rs
index a283bf1de76..f1fe495282a 100644
--- a/compiler/rustc_codegen_ssa/src/mir/coverageinfo.rs
+++ b/compiler/rustc_codegen_ssa/src/mir/coverageinfo.rs
@@ -9,11 +9,8 @@ use super::FunctionCx;
 impl<'a, 'tcx, Bx: BuilderMethods<'a, 'tcx>> FunctionCx<'a, 'tcx, Bx> {
     pub fn codegen_coverage(&self, bx: &mut Bx, coverage: Coverage, scope: SourceScope) {
         // Determine the instance that coverage data was originally generated for.
-        let scope_data = &self.mir.source_scopes[scope];
-        let instance = if let Some((inlined_instance, _)) = scope_data.inlined {
-            self.monomorphize(inlined_instance)
-        } else if let Some(inlined_scope) = scope_data.inlined_parent_scope {
-            self.monomorphize(self.mir.source_scopes[inlined_scope].inlined.unwrap().0)
+        let instance = if let Some(inlined) = scope.inlined_instance(&self.mir.source_scopes) {
+            self.monomorphize(inlined)
         } else {
             self.instance
         };
diff --git a/compiler/rustc_middle/src/mir/mod.rs b/compiler/rustc_middle/src/mir/mod.rs
index 93686128101..743e02ad3e1 100644
--- a/compiler/rustc_middle/src/mir/mod.rs
+++ b/compiler/rustc_middle/src/mir/mod.rs
@@ -1650,6 +1650,22 @@ impl SourceScope {
             ClearCrossCrate::Clear => None,
         }
     }
+
+    /// The instance this source scope was inlined from, if any.
+    #[inline]
+    pub fn inlined_instance<'tcx>(
+        self,
+        source_scopes: &IndexVec<SourceScope, SourceScopeData<'tcx>>,
+    ) -> Option<ty::Instance<'tcx>> {
+        let scope_data = &source_scopes[self];
+        if let Some((inlined_instance, _)) = scope_data.inlined {
+            Some(inlined_instance)
+        } else if let Some(inlined_scope) = scope_data.inlined_parent_scope {
+            Some(source_scopes[inlined_scope].inlined.unwrap().0)
+        } else {
+            None
+        }
+    }
 }
 
 #[derive(Clone, Debug, TyEncodable, TyDecodable, HashStable, TypeFoldable, TypeVisitable)]