[Coverage] Add support for Branch Coverage in LLVM Source-Based Code Coverage

This is an enhancement to LLVM Source-Based Code Coverage in clang to track how
many times individual branch-generating conditions are taken (evaluate to TRUE)
and not taken (evaluate to FALSE).  Individual conditions may comprise larger
boolean expressions using boolean logical operators.  This functionality is
very similar to what is supported by GCOV except that it is very closely
anchored to the ASTs.

Differential Revision: https://reviews.llvm.org/D84467

1 files changed, 19 insertions, 4 deletions

diff --git a/llvm/tools/llvm-cov/SourceCoverageView.cpp b/llvm/tools/llvm-cov/SourceCoverageView.cpp
index cd7395a..aca58a0 100644
--- a/llvm/tools/llvm-cov/SourceCoverageView.cpp
+++ b/llvm/tools/llvm-cov/SourceCoverageView.cpp
@@ -132,7 +132,8 @@ bool SourceCoverageView::shouldRenderRegionMarkers(
 }
 
 bool SourceCoverageView::hasSubViews() const {
-  return !ExpansionSubViews.empty() || !InstantiationSubViews.empty();
+  return !ExpansionSubViews.empty() || !InstantiationSubViews.empty() ||
+         !BranchSubViews.empty();
 }
 
 std::unique_ptr<SourceCoverageView>
@@ -167,6 +168,12 @@ void SourceCoverageView::addExpansion(
   ExpansionSubViews.emplace_back(Region, std::move(View));
 }
 
+void SourceCoverageView::addBranch(unsigned Line,
+                                   ArrayRef<CountedRegion> Regions,
+                                   std::unique_ptr<SourceCoverageView> View) {
+  BranchSubViews.emplace_back(Line, Regions, std::move(View));
+}
+
 void SourceCoverageView::addInstantiation(
     StringRef FunctionName, unsigned Line,
     std::unique_ptr<SourceCoverageView> View) {
@@ -187,14 +194,17 @@ void SourceCoverageView::print(raw_ostream &OS, bool WholeFile,
   renderTableHeader(OS, (ViewDepth > 0) ? 0 : getFirstUncoveredLineNo(),
                     ViewDepth);
 
-  // We need the expansions and instantiations sorted so we can go through them
-  // while we iterate lines.
+  // We need the expansions, instantiations, and branches sorted so we can go
+  // through them while we iterate lines.
   llvm::stable_sort(ExpansionSubViews);
   llvm::stable_sort(InstantiationSubViews);
+  llvm::stable_sort(BranchSubViews);
   auto NextESV = ExpansionSubViews.begin();
   auto EndESV = ExpansionSubViews.end();
   auto NextISV = InstantiationSubViews.begin();
   auto EndISV = InstantiationSubViews.end();
+  auto NextBRV = BranchSubViews.begin();
+  auto EndBRV = BranchSubViews.end();
 
   // Get the coverage information for the file.
   auto StartSegment = CoverageInfo.begin();
@@ -234,7 +244,7 @@ void SourceCoverageView::print(raw_ostream &OS, bool WholeFile,
     if (shouldRenderRegionMarkers(*LCI))
       renderRegionMarkers(OS, *LCI, ViewDepth);
 
-    // Show the expansions and instantiations for this line.
+    // Show the expansions, instantiations, and branches for this line.
     bool RenderedSubView = false;
     for (; NextESV != EndESV && NextESV->getLine() == LI.line_number();
          ++NextESV) {
@@ -257,6 +267,11 @@ void SourceCoverageView::print(raw_ostream &OS, bool WholeFile,
       renderInstantiationView(OS, *NextISV, ViewDepth + 1);
       RenderedSubView = true;
     }
+    for (; NextBRV != EndBRV && NextBRV->Line == LI.line_number(); ++NextBRV) {
+      renderViewDivider(OS, ViewDepth + 1);
+      renderBranchView(OS, *NextBRV, ViewDepth + 1);
+      RenderedSubView = true;
+    }
     if (RenderedSubView)
       renderViewDivider(OS, ViewDepth + 1);
     renderLineSuffix(OS, ViewDepth);