[llvm-cov] New parameters to set coverage coverage_watermark

Add a pairs of parameters to set coverage watermark for llvm-cov, and
user can change the percentage thresholds marked with different colors
in the report.

Patch By: tanjinhua

Differential Revision: https://reviews.llvm.org/D116876

llvm/docs/CommandGuide/llvm-cov.rst

@@ -349,6 +349,13 @@ OPTIONS
  to generate the coverage data on one machine, and then use llvm-cov on a
  different machine where you have the same files on a different path.
 
+.. option:: -coverage-watermark=<high>,<low>
+
+ Set high and low watermarks for coverage in html format output. This allows you
+ to set the high and low watermark of coverage as desired, green when
+ coverage >= high, red when coverage < low, and yellow otherwise. Both high and
+ low should be between 0-100 and high > low.
+
 .. program:: llvm-cov report
 
 .. _llvm-cov-report:

llvm/tools/llvm-cov/CodeCoverage.cpp

@@ -973,6 +973,11 @@ int CodeCoverageTool::doShow(int argc, const char **argv,
       "project-title", cl::Optional,
       cl::desc("Set project title for the coverage report"));
 
+  cl::opt<std::string> CovWatermark(
+      "coverage-watermark", cl::Optional,
+      cl::desc("<high>,<low> value indicate thresholds for high and low"
+               "coverage watermark"));
+
   auto Err = commandLineParser(argc, argv);
   if (Err)
     return Err;
@@ -982,6 +987,47 @@ int CodeCoverageTool::doShow(int argc, const char **argv,
     return 1;
   }
 
+  ViewOpts.HighCovWatermark = 100.0;
+  ViewOpts.LowCovWatermark = 80.0;
+  if (!CovWatermark.empty()) {
+    auto WaterMarkPair = StringRef(CovWatermark).split(',');
+    if (WaterMarkPair.first.empty() || WaterMarkPair.second.empty()) {
+      error("invalid argument '" + CovWatermark +
+                "', must be in format 'high,low'",
+            "-coverage-watermark");
+      return 1;
+    }
+
+    char *EndPointer = nullptr;
+    ViewOpts.HighCovWatermark =
+        strtod(WaterMarkPair.first.begin(), &EndPointer);
+    if (EndPointer != WaterMarkPair.first.end()) {
+      error("invalid number '" + WaterMarkPair.first +
+                "', invalid value for 'high'",
+            "-coverage-watermark");
+      return 1;
+    }
+
+    ViewOpts.LowCovWatermark =
+        strtod(WaterMarkPair.second.begin(), &EndPointer);
+    if (EndPointer != WaterMarkPair.second.end()) {
+      error("invalid number '" + WaterMarkPair.second +
+                "', invalid value for 'low'",
+            "-coverage-watermark");
+      return 1;
+    }
+
+    if (ViewOpts.HighCovWatermark > 100 || ViewOpts.LowCovWatermark < 0 ||
+        ViewOpts.HighCovWatermark <= ViewOpts.LowCovWatermark) {
+      error(
+          "invalid number range '" + CovWatermark +
+              "', must be both high and low should be between 0-100, and high "
+              "> low",
+          "-coverage-watermark");
+      return 1;
+    }
+  }
+
   ViewOpts.ShowLineNumbers = true;
   ViewOpts.ShowLineStats = ShowLineExecutionCounts.getNumOccurrences() != 0 ||
                            !ShowRegions || ShowBestLineRegionsCounts;

llvm/tools/llvm-cov/CoverageViewOptions.h

@@ -50,6 +50,8 @@ struct CoverageViewOptions {
   std::string CreatedTimeStr;
   unsigned NumThreads;
   std::string CompilationDirectory;
+  float HighCovWatermark;
+  float LowCovWatermark;
 
   /// Change the output's stream color if the colors are enabled.
   ColoredRawOstream colored_ostream(raw_ostream &OS,

llvm/tools/llvm-cov/SourceCoverageViewHTML.cpp

@@ -338,24 +338,24 @@ void CoveragePrinterHTML::emitFileSummary(raw_ostream &OS, StringRef SF,
   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,
-                                              float Pctg) {
-    std::string S;
-    {
-      raw_string_ostream RSO{S};
-      if (Total)
-        RSO << format("%*.2f", 7, Pctg) << "% ";
-      else
-        RSO << "- ";
-      RSO << '(' << Hit << '/' << Total << ')';
-    }
-    const char *CellClass = "column-entry-yellow";
-    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));
-  };
+  auto AddCoverageTripleToColumn =
+      [&Columns, this](unsigned Hit, unsigned Total, float Pctg) {
+        std::string S;
+        {
+          raw_string_ostream RSO{S};
+          if (Total)
+            RSO << format("%*.2f", 7, Pctg) << "% ";
+          else
+            RSO << "- ";
+          RSO << '(' << Hit << '/' << Total << ')';
+        }
+        const char *CellClass = "column-entry-yellow";
+        if (Pctg >= Opts.HighCovWatermark)
+          CellClass = "column-entry-green";
+        else if (Pctg < Opts.LowCovWatermark)
+          CellClass = "column-entry-red";
+        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;