Also dump coverage info

Author: bjorn3

compiler/rustc_mir_build/src/builder/coverageinfo.rs

@@ -157,6 +157,21 @@ impl CoverageInfoBuilder {
         // if there's nothing interesting in it.
         Box::new(CoverageInfoHi { num_block_markers, branch_spans })
     }
+
+    pub(crate) fn as_done(&self) -> Box<CoverageInfoHi> {
+        let &Self { nots: _, markers: BlockMarkerGen { num_block_markers }, ref branch_info } =
+            self;
+
+        let branch_spans = branch_info
+            .as_ref()
+            .map(|branch_info| branch_info.branch_spans.as_slice())
+            .unwrap_or_default()
+            .to_owned();
+
+        // For simplicity, always return an info struct (without Option), even
+        // if there's nothing interesting in it.
+        Box::new(CoverageInfoHi { num_block_markers, branch_spans })
+    }
 }
 
 impl<'tcx> Builder<'_, 'tcx> {
@@ -208,6 +223,7 @@ impl<'tcx> Builder<'_, 'tcx> {
             mir::TerminatorKind::if_(mir::Operand::Copy(place), true_block, false_block),
         );
 
+        // Separate path for handling branches when MC/DC is enabled.
         coverage_info.register_two_way_branch(&mut self.cfg, source_info, true_block, false_block);
 
         let join_block = self.cfg.start_new_block();

compiler/rustc_mir_build/src/builder/mod.rs

@@ -803,7 +803,7 @@ impl<'a, 'tcx> Builder<'a, 'tcx> {
             self.coroutine.clone(),
             None,
         );
-        //body.coverage_info_hi = self.coverage_info.clone().map(|b| b.into_done());
+        body.coverage_info_hi = self.coverage_info.clone().map(|b| b.as_done());
 
         use rustc_middle::mir::pretty;
         let options = pretty::PrettyPrintMirOptions::from_cli(self.tcx);