Simplify StaticDef to Instance conversion

Author: celinval

compiler/rustc_smir/src/rustc_smir/context.rs

@@ -322,9 +322,9 @@ impl<'tcx> Context for TablesWrapper<'tcx> {
         matches!(instance.def, ty::InstanceDef::DropGlue(_, None))
     }
 
-    fn mono_instance(&self, item: stable_mir::CrateItem) -> stable_mir::mir::mono::Instance {
+    fn mono_instance(&self, def_id: stable_mir::DefId) -> stable_mir::mir::mono::Instance {
         let mut tables = self.0.borrow_mut();
-        let def_id = tables[item.0];
+        let def_id = tables[def_id];
         Instance::mono(tables.tcx, def_id).stable(&mut *tables)
     }
 

compiler/stable_mir/src/compiler_interface.rs

@@ -125,7 +125,7 @@ pub trait Context {
 
     /// Convert a non-generic crate item into an instance.
     /// This function will panic if the item is generic.
-    fn mono_instance(&self, item: CrateItem) -> Instance;
+    fn mono_instance(&self, def_id: DefId) -> Instance;
 
     /// Item requires monomorphization.
     fn requires_monomorphization(&self, def_id: DefId) -> bool;

compiler/stable_mir/src/mir/mono.rs

@@ -143,8 +143,9 @@ impl TryFrom<CrateItem> for Instance {
 
     fn try_from(item: CrateItem) -> Result<Self, Self::Error> {
         with(|context| {
-            if !context.requires_monomorphization(item.0) {
-                Ok(context.mono_instance(item))
+            let def_id = item.def_id();
+            if !context.requires_monomorphization(def_id) {
+                Ok(context.mono_instance(def_id))
             } else {
                 Err(Error::new("Item requires monomorphization".to_string()))
             }
@@ -223,7 +224,7 @@ impl TryFrom<Instance> for StaticDef {
 impl From<StaticDef> for Instance {
     fn from(value: StaticDef) -> Self {
         // A static definition should always be convertible to an instance.
-        Instance::try_from(CrateItem::from(value)).unwrap()
+        with(|cx| cx.mono_instance(value.def_id()))
     }
 }