move checking ptr tracking on item pop into cold helper function

Author: RalfJung

src/stacked_borrows.rs

@@ -326,11 +326,22 @@ impl<'tcx> Stack {
         global: &GlobalStateInner,
         alloc_history: &mut AllocHistory,
     ) -> InterpResult<'tcx> {
-        if global.tracked_pointer_tags.contains(&item.tag) {
-            register_diagnostic(NonHaltingDiagnostic::PoppedPointerTag(
-                *item,
-                provoking_access.map(|(tag, _alloc_range, _size, access)| (tag, access)),
-            ));
+        if !global.tracked_pointer_tags.is_empty() {
+            check_tracked(item, &provoking_access, global);
+
+            #[inline(never)] // cold path
+            fn check_tracked(
+                item: &Item,
+                provoking_access: &Option<(SbTagExtra, AllocRange, Size, AccessKind)>,
+                global: &GlobalStateInner,
+            ) {
+                if global.tracked_pointer_tags.contains(&item.tag) {
+                    register_diagnostic(NonHaltingDiagnostic::PoppedPointerTag(
+                        *item,
+                        provoking_access.map(|(tag, _alloc_range, _size, access)| (tag, access)),
+                    ));
+                }
+            }
         }
 
         if let Some(call) = item.protector {