[llvm-cov] Avoid 0% when reporting something that's 0/0

This commit makes llvm-cov avoid showing 0% (0/0) coverage for things
like file function coverage, etc. in reports and HTML output. This can happen
for files like headers that have macros but no functions. This commit makes
llvm-cov report - (0/0) instead.

rdar://29246480

Differential Revision: https://reviews.llvm.org/D26615

llvm-svn: 287539

2 files changed, 36 insertions, 20 deletions

diff --git a/llvm/tools/llvm-cov/CoverageReport.cpp b/llvm/tools/llvm-cov/CoverageReport.cpp
index 5a56579149a..e88cb186acd 100644
--- a/llvm/tools/llvm-cov/CoverageReport.cpp
+++ b/llvm/tools/llvm-cov/CoverageReport.cpp
@@ -154,36 +154,48 @@ void CoverageReport::render(const FileCoverageSummary &File,
                (unsigned)File.RegionCoverage.NumRegions);
   Options.colored_ostream(OS, FileCoverageColor) << format(
       "%*u", FileReportColumns[2], (unsigned)File.RegionCoverage.NotCovered);
-  Options.colored_ostream(OS, FileCoverageColor)
-      << format("%*.2f", FileReportColumns[3] - 1,
-                File.RegionCoverage.getPercentCovered())
-      << '%';
+  if (File.RegionCoverage.NumRegions)
+    Options.colored_ostream(OS, FileCoverageColor)
+        << format("%*.2f", FileReportColumns[3] - 1,
+                  File.RegionCoverage.getPercentCovered())
+        << '%';
+  else
+    OS << column("-", FileReportColumns[3], Column::RightAlignment);
   OS << format("%*u", FileReportColumns[4],
                (unsigned)File.FunctionCoverage.NumFunctions);
   OS << format("%*u", FileReportColumns[5],
                (unsigned)(File.FunctionCoverage.NumFunctions -
                           File.FunctionCoverage.Executed));
-  Options.colored_ostream(OS, FuncCoverageColor)
-      << format("%*.2f", FileReportColumns[6] - 1,
-                File.FunctionCoverage.getPercentCovered())
-      << '%';
+  if (File.FunctionCoverage.NumFunctions)
+    Options.colored_ostream(OS, FuncCoverageColor)
+        << format("%*.2f", FileReportColumns[6] - 1,
+                  File.FunctionCoverage.getPercentCovered())
+        << '%';
+  else
+    OS << column("-", FileReportColumns[6], Column::RightAlignment);
   OS << format("%*u", FileReportColumns[7],
                (unsigned)File.InstantiationCoverage.NumFunctions);
   OS << format("%*u", FileReportColumns[8],
                (unsigned)(File.InstantiationCoverage.NumFunctions -
                           File.InstantiationCoverage.Executed));
-  Options.colored_ostream(OS, InstantiationCoverageColor)
-      << format("%*.2f", FileReportColumns[9] - 1,
-                File.InstantiationCoverage.getPercentCovered())
-      << '%';
+  if (File.InstantiationCoverage.NumFunctions)
+    Options.colored_ostream(OS, InstantiationCoverageColor)
+        << format("%*.2f", FileReportColumns[9] - 1,
+                  File.InstantiationCoverage.getPercentCovered())
+        << '%';
+  else
+    OS << column("-", FileReportColumns[9], Column::RightAlignment);
   OS << format("%*u", FileReportColumns[10],
                (unsigned)File.LineCoverage.NumLines);
   Options.colored_ostream(OS, LineCoverageColor) << format(
       "%*u", FileReportColumns[11], (unsigned)File.LineCoverage.NotCovered);
-  Options.colored_ostream(OS, LineCoverageColor)
-      << format("%*.2f", FileReportColumns[12] - 1,
-                File.LineCoverage.getPercentCovered())
-      << '%';
+  if (File.LineCoverage.NumLines)
+    Options.colored_ostream(OS, LineCoverageColor)
+        << format("%*.2f", FileReportColumns[12] - 1,
+                  File.LineCoverage.getPercentCovered())
+        << '%';
+  else
+    OS << column("-", FileReportColumns[12], Column::RightAlignment);
   OS << "\n";
 }
 
diff --git a/llvm/tools/llvm-cov/SourceCoverageViewHTML.cpp b/llvm/tools/llvm-cov/SourceCoverageViewHTML.cpp
index 8fc01ef0d88..64b888e89d7 100644
--- a/llvm/tools/llvm-cov/SourceCoverageViewHTML.cpp
+++ b/llvm/tools/llvm-cov/SourceCoverageViewHTML.cpp
@@ -307,13 +307,17 @@ void CoveragePrinterHTML::emitFileSummary(raw_ostream &OS, StringRef SF,
     std::string S;
     {
       raw_string_ostream RSO{S};
-      RSO << format("%*.2f", 7, Pctg) << "% (" << Hit << '/' << Total << ')';
+      if (Total)
+        RSO << format("%*.2f", 7, Pctg) << "% ";
+      else
+        RSO << "- ";
+      RSO << '(' << Hit << '/' << Total << ')';
     }
     const char *CellClass = "column-entry-yellow";
-    if (Pctg < 80.0)
-      CellClass = "column-entry-red";
-    else if (Hit == Total)
+    if (Hit == Total)
       CellClass = "column-entry-green";
+    else if (Pctg < 80.0)
+      CellClass = "column-entry-red";
     Columns.emplace_back(tag("td", tag("pre", S), CellClass));
   };