rustc_mir: track inlined callees in SourceScopeData.

compiler/rustc_middle/src/mir/mod.rs

@@ -161,7 +161,7 @@ pub struct Body<'tcx> {
 
     /// A list of source scopes; these are referenced by statements
     /// and used for debuginfo. Indexed by a `SourceScope`.
-    pub source_scopes: IndexVec<SourceScope, SourceScopeData>,
+    pub source_scopes: IndexVec<SourceScope, SourceScopeData<'tcx>>,
 
     /// The yield type of the function, if it is a generator.
     pub yield_ty: Option<Ty<'tcx>>,
@@ -244,7 +244,7 @@ impl<'tcx> Body<'tcx> {
     pub fn new(
         source: MirSource<'tcx>,
         basic_blocks: IndexVec<BasicBlock, BasicBlockData<'tcx>>,
-        source_scopes: IndexVec<SourceScope, SourceScopeData>,
+        source_scopes: IndexVec<SourceScope, SourceScopeData<'tcx>>,
         local_decls: LocalDecls<'tcx>,
         user_type_annotations: ty::CanonicalUserTypeAnnotations<'tcx>,
         arg_count: usize,
@@ -1868,11 +1868,16 @@ rustc_index::newtype_index! {
     }
 }
 
-#[derive(Clone, Debug, TyEncodable, TyDecodable, HashStable)]
-pub struct SourceScopeData {
+#[derive(Clone, Debug, TyEncodable, TyDecodable, HashStable, TypeFoldable)]
+pub struct SourceScopeData<'tcx> {
     pub span: Span,
     pub parent_scope: Option<SourceScope>,
 
+    /// Whether this scope is the root of a scope tree of another body,
+    /// inlined into this body by the MIR inliner.
+    /// `ty::Instance` is the callee, and the `Span` is the call site.
+    pub inlined: Option<(ty::Instance<'tcx>, Span)>,
+
     /// Crate-local information for this source scope, that can't (and
     /// needn't) be tracked across crates.
     pub local_data: ClearCrossCrate<SourceScopeLocalData>,

compiler/rustc_middle/src/mir/type_foldable.rs

@@ -10,7 +10,6 @@ CloneTypeFoldableAndLiftImpls! {
     FakeReadCause,
     RetagKind,
     SourceScope,
-    SourceScopeData,
     SourceScopeLocalData,
     UserTypeAnnotationIndex,
 }

compiler/rustc_middle/src/mir/visit.rs

@@ -85,7 +85,7 @@ macro_rules! make_mir_visitor {
             }
 
             fn visit_source_scope_data(&mut self,
-                                           scope_data: & $($mutability)? SourceScopeData) {
+                                           scope_data: & $($mutability)? SourceScopeData<'tcx>) {
                 self.super_source_scope_data(scope_data);
             }
 
@@ -317,10 +317,14 @@ macro_rules! make_mir_visitor {
                 }
             }
 
-            fn super_source_scope_data(&mut self, scope_data: & $($mutability)? SourceScopeData) {
+            fn super_source_scope_data(
+                &mut self,
+                scope_data: & $($mutability)? SourceScopeData<'tcx>,
+            ) {
                 let SourceScopeData {
                     span,
                     parent_scope,
+                    inlined,
                     local_data: _,
                 } = scope_data;
 
@@ -328,6 +332,31 @@ macro_rules! make_mir_visitor {
                 if let Some(parent_scope) = parent_scope {
                     self.visit_source_scope(parent_scope);
                 }
+                if let Some((callee, callsite_span)) = inlined {
+                    let location = START_BLOCK.start_location();
+
+                    self.visit_span(callsite_span);
+
+                    let ty::Instance { def: callee_def, substs: callee_substs } = callee;
+                    match callee_def {
+                        ty::InstanceDef::Item(_def_id) => {}
+
+                        ty::InstanceDef::Intrinsic(_def_id) |
+                        ty::InstanceDef::VtableShim(_def_id) |
+                        ty::InstanceDef::ReifyShim(_def_id) |
+                        ty::InstanceDef::Virtual(_def_id, _) |
+                        ty::InstanceDef::ClosureOnceShim { call_once: _def_id } |
+                        ty::InstanceDef::DropGlue(_def_id, None) => {}
+
+                        ty::InstanceDef::FnPtrShim(_def_id, ty) |
+                        ty::InstanceDef::DropGlue(_def_id, Some(ty)) |
+                        ty::InstanceDef::CloneShim(_def_id, ty) => {
+                            // FIXME(eddyb) use a better `TyContext` here.
+                            self.visit_ty(ty, TyContext::Location(location));
+                        }
+                    }
+                    self.visit_substs(callee_substs, location);
+                }
             }
 
             fn super_statement(&mut self,