[llvm-cov] Track function and instantiation coverage separately

These are distinct statistics which are useful to look at separately.

Example: say you have a template function "foo" with 5 instantiations
and only 3 of them are covered. Then this contributes (1/1) to the total
function coverage and (3/5) to the total instantiation coverage. I.e,
the old "Function Coverage" column has been renamed to "Instantiation
Coverage", and the new "Function Coverage" aggregates information from
the various instantiations of a function.

One benefit of making this switch is that the Line and Region coverage
columns will start making sense. Let's continue the example and assume
that the 5 instantiations of "foo" cover {2, 4, 6, 8, 10} out of 10
lines respectively. The new line coverage for "foo" is (10/10), not
(30/50).  The old scenario got confusing because we'd report that there
were more lines in a file than what was actually possible.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@281875 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 5 insertions, 2 deletions

diff --git a/tools/llvm-cov/SourceCoverageViewHTML.cpp b/tools/llvm-cov/SourceCoverageViewHTML.cpp
index e64f31d546e..1ef3219b103 100644
--- a/tools/llvm-cov/SourceCoverageViewHTML.cpp
+++ b/tools/llvm-cov/SourceCoverageViewHTML.cpp
@@ -287,8 +287,8 @@ void CoveragePrinterHTML::closeViewFile(OwnedStream OS) {
 static void emitColumnLabelsForIndex(raw_ostream &OS) {
   SmallVector<std::string, 4> Columns;
   Columns.emplace_back(tag("td", "Filename", "column-entry-left"));
-  for (const char *Label :
-       {"Function Coverage", "Line Coverage", "Region Coverage"})
+  for (const char *Label : {"Function Coverage", "Instantiation Coverage",
+                            "Line Coverage", "Region Coverage"})
     Columns.emplace_back(tag("td", Label, "column-entry"));
   OS << tag("tr", join(Columns.begin(), Columns.end(), ""));
 }
@@ -334,6 +334,9 @@ void CoveragePrinterHTML::emitFileSummary(raw_ostream &OS, StringRef SF,
   AddCoverageTripleToColumn(FCS.FunctionCoverage.Executed,
                             FCS.FunctionCoverage.NumFunctions,
                             FCS.FunctionCoverage.getPercentCovered());
+  AddCoverageTripleToColumn(FCS.InstantiationCoverage.Executed,
+                            FCS.InstantiationCoverage.NumFunctions,
+                            FCS.InstantiationCoverage.getPercentCovered());
   AddCoverageTripleToColumn(FCS.LineCoverage.Covered, FCS.LineCoverage.NumLines,
                             FCS.LineCoverage.getPercentCovered());
   AddCoverageTripleToColumn(FCS.RegionCoverage.Covered,