InstrProf: Handle unknown functions if they consist only of zero-regions

This comes up when we generate coverage for a function but don't end
up emitting the function at all - dead static functions or inline
functions that aren't referenced in a particular TU, for example. In
these cases we'd like to show that the function was never called,
which is trivially true.

llvm-svn: 229717

1 files changed, 13 insertions, 0 deletions

diff --git a/llvm/unittests/ProfileData/CoverageMappingTest.cpp b/llvm/unittests/ProfileData/CoverageMappingTest.cpp
index d079b479216..5e64843b6d6 100644
--- a/llvm/unittests/ProfileData/CoverageMappingTest.cpp
+++ b/llvm/unittests/ProfileData/CoverageMappingTest.cpp
@@ -209,4 +209,17 @@ TEST_F(CoverageMappingTest, basic_coverage_iteration) {
   ASSERT_EQ(CoverageSegment(11, 11, false),   Segments[6]);
 }
 
+TEST_F(CoverageMappingTest, uncovered_function) {
+  readProfCounts();
+
+  addCMR(Counter::getZero(), "file1", 1, 2, 3, 4);
+  loadCoverageMapping("func", 0x1234);
+
+  CoverageData Data = LoadedCoverage->getCoverageForFile("file1");
+  std::vector<CoverageSegment> Segments(Data.begin(), Data.end());
+  ASSERT_EQ(2U, Segments.size());
+  ASSERT_EQ(CoverageSegment(1, 2, 0, true), Segments[0]);
+  ASSERT_EQ(CoverageSegment(3, 4, false),   Segments[1]);
+}
+
 } // end anonymous namespace