add place mention for #[loop_match] scrutinee

Author: folkertdev

compiler/rustc_mir_build/src/builder/expr/into.rs

@@ -295,9 +295,11 @@ impl<'a, 'tcx> Builder<'a, 'tcx> {
                     this.diverge_from(loop_block);
 
                     // Logic for `match`.
-                    let scrutinee_place_builder =
-                        unpack!(body_block = this.as_place_builder(body_block, scrutinee));
                     let scrutinee_span = this.thir.exprs[scrutinee].span;
+                    let scrutinee_place_builder = unpack!(
+                        body_block = this.lower_scrutinee(body_block, scrutinee, scrutinee_span)
+                    );
+
                     let match_start_span = match_span.shrink_to_lo().to(scrutinee_span);
 
                     let mut patterns = Vec::with_capacity(arms.len());

compiler/rustc_mir_build/src/builder/matches/mod.rs

@@ -407,7 +407,7 @@ impl<'a, 'tcx> Builder<'a, 'tcx> {
     }
 
     /// Evaluate the scrutinee and add the PlaceMention for it.
-    fn lower_scrutinee(
+    pub(crate) fn lower_scrutinee(
         &mut self,
         mut block: BasicBlock,
         scrutinee_id: ExprId,