[llvm-cov] Rearrange entries in HTML report index.

[efriedma]

Summary

Files which don't contain any functions are likely useless; don't include them in the main table. Put the links at the bottom of the page, in case someone wants to figure out coverage for code inside a macro.

Not sure if this is the best solution, but it seems like an improvement.

[vsk]

This seems like a clean solution. The total file coverage summaries aren't affected, which is nice.

Could you make a similar change to CoverageReport::prepareFileReports? We try to maintain parity between the text/html emitters, and the text emitter uses CoverageReport to prepare its index file. This should do it:

CoverageReport.patch888 BDownload

.

You could add a RUN line to the test you've updated here, and use -format text, to get a test case. None of the other tests appear to be affected.

[efriedma]

Update text reports.

[vsk]

Thanks, lgtm.

test/tools/llvm-cov/zeroFunctionFile.c

 #include "Inputs/zeroFunctionFile.h"
 
 int foo(int x) {
   return NOFUNCTIONS(x);
 }
 int main() {
   return foo(2);
 }
 
 // RUN: llvm-profdata merge %S/Inputs/zeroFunctionFile.proftext -o %t.profdata
 
 // RUN: llvm-cov report %S/Inputs/zeroFunctionFile.covmapping -instr-profile %t.profdata 2>&1 | FileCheck --check-prefix=REPORT --strict-whitespace %s
-// REPORT: 0                 0         -           0                 0         -               0               0         -           0                 0         -
-// REPORT-NO: 0%
+// REPORT: Files which contain no functions
+// REPORT: zeroFunctionFile.h
 
 // RUN: llvm-cov show -j 1 %S/Inputs/zeroFunctionFile.covmapping -format html -instr-profile %t.profdata -o %t.dir
 // RUN: FileCheck %s -input-file=%t.dir/index.html -check-prefix=HTML
-// HTML: <td class='column-entry-green'><pre>- (0/0)
 // HTML-NO: 0.00% (0/0)
+// HTML: Files which contain no functions
+// HTML: zeroFunctionFile.h

tools/llvm-cov/CoverageReport.cpp

OS << column("Filename", FileReportColumns[0])
      << column("Missed Insts.", FileReportColumns[8], Column::RightAlignment)
      << column("Executed", FileReportColumns[9], Column::RightAlignment)
      << column("Lines", FileReportColumns[10], Column::RightAlignment)
      << column("Missed Lines", FileReportColumns[11], Column::RightAlignment)
      << column("Cover", FileReportColumns[12], Column::RightAlignment) << "\n";
   renderDivider(FileReportColumns, OS);
   OS << "\n";
 
+  bool EmptyFiles = false;
+  for (const FileCoverageSummary &FCS : FileReports) {
+    if (FCS.FunctionCoverage.NumFunctions)
+      render(FCS, OS);
+    else
+      EmptyFiles = true;
+  }
+
+  if (EmptyFiles) {
+    OS << "\n"
+       << "Files which contain no functions:\n";
+
     for (const FileCoverageSummary &FCS : FileReports)
+      if (!FCS.FunctionCoverage.NumFunctions)
         render(FCS, OS);
+  }
 
   renderDivider(FileReportColumns, OS);
   OS << "\n";
   render(Totals, OS);
 }
 
 } // end namespace llvm

tools/llvm-cov/SourceCoverageViewHTML.h

public:
 
   CoveragePrinterHTML(const CoverageViewOptions &Opts)
       : CoveragePrinter(Opts) {}
 
 private:
   void emitFileSummary(raw_ostream &OS, StringRef SF,
                        const FileCoverageSummary &FCS,
                        bool IsTotals = false) const;
+  std::string buildLinkToFile(StringRef SF,
+                              const FileCoverageSummary &FCS) const;
 };
 
 /// \brief A code coverage view which supports html-based rendering.
 class SourceCoverageViewHTML : public SourceCoverageView {
   void renderViewHeader(raw_ostream &OS) override;
 
   void renderViewFooter(raw_ostream &OS) override;
 

tools/llvm-cov/SourceCoverageViewHTML.cpp

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", "Instantiation Coverage",
                             "Line Coverage", "Region Coverage"})
     Columns.emplace_back(tag("td", Label, "column-entry"));
   OS << tag("tr", join(Columns.begin(), Columns.end(), ""));
 }
 
+std::string
+CoveragePrinterHTML::buildLinkToFile(StringRef SF,
+                                     const FileCoverageSummary &FCS) const {
+  SmallString<128> LinkTextStr(sys::path::relative_path(FCS.Name));
+  sys::path::remove_dots(LinkTextStr, /*remove_dot_dots=*/true);
+  sys::path::native(LinkTextStr);
+  std::string LinkText = escape(LinkTextStr, Opts);
+  std::string LinkTarget =
+      escape(getOutputPath(SF, "html", /*InToplevel=*/false), Opts);
+  return a(LinkTarget, LinkText);
+}
+
 /// Render a file coverage summary (\p FCS) in a table row. If \p IsTotals is
 /// false, link the summary to \p SF.
 void CoveragePrinterHTML::emitFileSummary(raw_ostream &OS, StringRef SF,
                                           const FileCoverageSummary &FCS,
                                           bool IsTotals) const {
   SmallVector<std::string, 8> Columns;
 
   // Format a coverage triple and add the result to the list of columns.
auto AddCoverageTripleToColumn = [&Columns](unsigned Hit, unsigned Total,
     Columns.emplace_back(tag("td", tag("pre", S), CellClass));
   };
 
   // Simplify the display file path, and wrap it in a link if requested.
   std::string Filename;
   if (IsTotals) {
     Filename = "TOTALS";
   } else {
-    SmallString<128> LinkTextStr(sys::path::relative_path(FCS.Name));
-    sys::path::remove_dots(LinkTextStr, /*remove_dot_dots=*/true);
-    sys::path::native(LinkTextStr);
-    std::string LinkText = escape(LinkTextStr, Opts);
-    std::string LinkTarget =
-        escape(getOutputPath(SF, "html", /*InToplevel=*/false), Opts);
-    Filename = a(LinkTarget, LinkText);
+    Filename = buildLinkToFile(SF, FCS);
   }
 
   Columns.emplace_back(tag("td", tag("pre", Filename)));
   AddCoverageTripleToColumn(FCS.FunctionCoverage.Executed,
                             FCS.FunctionCoverage.NumFunctions,
                             FCS.FunctionCoverage.getPercentCovered());
   AddCoverageTripleToColumn(FCS.InstantiationCoverage.Executed,
                             FCS.InstantiationCoverage.NumFunctions,
Error CoveragePrinterHTML::createIndexFile(
   // Emit a link to some documentation.
   OSRef << tag("p", "Click " +
                         a("http://clang.llvm.org/docs/"
                           "SourceBasedCodeCoverage.html#interpreting-reports",
                           "here") +
                         " for information about interpreting this report.");
 
   // Emit a table containing links to reports for each file in the covmapping.
+  // Exclude files which don't contain any regions.
   OSRef << BeginCenteredDiv << BeginTable;
   emitColumnLabelsForIndex(OSRef);
   FileCoverageSummary Totals("TOTALS");
   auto FileReports =
       CoverageReport::prepareFileReports(Coverage, Totals, SourceFiles);
-  for (unsigned I = 0, E = FileReports.size(); I < E; ++I)
+  bool EmptyFiles = false;
+  for (unsigned I = 0, E = FileReports.size(); I < E; ++I) {
+    if (FileReports[I].FunctionCoverage.NumFunctions)
       emitFileSummary(OSRef, SourceFiles[I], FileReports[I]);
+    else
+      EmptyFiles = true;
+  }
   emitFileSummary(OSRef, "Totals", Totals, /*IsTotals=*/true);
-  OSRef << EndTable << EndCenteredDiv
-        << tag("h5", escape(Opts.getLLVMVersionString(), Opts));
+  OSRef << EndTable << EndCenteredDiv;
+
+  // Emit links to files which don't contain any functions. These are normally
+  // not very useful, but could be relevant for code which abuses the
+  // preprocessor.
+  if (EmptyFiles) {
+    OSRef << tag("p", "Files which contain no functions. (These "
+                      "files contain code pulled into other files "
+                      "by the preprocessor.)\n");
+    OSRef << BeginCenteredDiv << BeginTable;
+    for (unsigned I = 0, E = FileReports.size(); I < E; ++I)
+      if (!FileReports[I].FunctionCoverage.NumFunctions) {
+        std::string Link = buildLinkToFile(SourceFiles[I], FileReports[I]);
+        OSRef << tag("tr", tag("td", tag("pre", Link)), "light-row") << '\n';
+      }
+    OSRef << EndTable << EndCenteredDiv;
+  }
+
+  OSRef << tag("h5", escape(Opts.getLLVMVersionString(), Opts));
   emitEpilog(OSRef);
 
   return Error::success();
 }
 
 void SourceCoverageViewHTML::renderViewHeader(raw_ostream &OS) {
   OS << BeginCenteredDiv << BeginTable;
 }