llvm-cov: Rework the API for getting the coverage of a file (NFC)

This encapsulates how we handle the coverage regions of a file or
function. In the old model, the user had to deal with nested regions,
so they needed to maintain their own auxiliary data structures to get
any useful information out of this. The new API provides a sequence of
non-overlapping coverage segments, which makes it possible to render
coverage information in a single pass and avoids a fair amount of
extra work.

llvm-svn: 217975

1 files changed, 105 insertions, 240 deletions

diff --git a/llvm/tools/llvm-cov/SourceCoverageView.cpp b/llvm/tools/llvm-cov/SourceCoverageView.cpp
index a83bd54e15e..2a212e5173d 100644
--- a/llvm/tools/llvm-cov/SourceCoverageView.cpp
+++ b/llvm/tools/llvm-cov/SourceCoverageView.cpp
@@ -12,54 +12,54 @@
 //===----------------------------------------------------------------------===//
 
 #include "SourceCoverageView.h"
+#include "llvm/ADT/Optional.h"
 #include "llvm/ADT/SmallString.h"
 #include "llvm/Support/LineIterator.h"
 
 using namespace llvm;
 
 void SourceCoverageView::renderLine(raw_ostream &OS, StringRef Line,
-                                    ArrayRef<HighlightRange> Ranges) {
-  if (Ranges.empty()) {
-    OS << Line << "\n";
-    return;
-  }
-  if (Line.empty())
-    Line = " ";
-
-  unsigned PrevColumnStart = 0;
-  unsigned Start = 1;
-  for (const auto &Range : Ranges) {
-    if (PrevColumnStart == Range.ColumnStart)
-      continue;
-
-    // Show the unhighlighted part
-    unsigned ColumnStart = PrevColumnStart = Range.ColumnStart;
-    OS << Line.substr(Start - 1, ColumnStart - Start);
-
-    // Show the highlighted part
-    auto Color = Range.Kind == HighlightRange::NotCovered ? raw_ostream::RED
-                                                          : raw_ostream::CYAN;
-    OS.changeColor(Color, false, true);
-    unsigned ColumnEnd = std::min(Range.ColumnEnd, (unsigned)Line.size() + 1);
-    OS << Line.substr(ColumnStart - 1, ColumnEnd - ColumnStart);
-    Start = ColumnEnd;
-    OS.resetColor();
+                                    int64_t LineNumber,
+                                    const CoverageSegment *WrappedSegment,
+                                    ArrayRef<const CoverageSegment *> Segments,
+                                    unsigned ExpansionCol) {
+  Optional<raw_ostream::Colors> Highlight;
+  SmallVector<std::pair<unsigned, unsigned>, 2> HighlightedRanges;
+
+  // The first segment overlaps from a previous line, so we treat it specially.
+  if (WrappedSegment && WrappedSegment->HasCount && WrappedSegment->Count == 0)
+    Highlight = raw_ostream::RED;
+
+  // Output each segment of the line, possibly highlighted.
+  unsigned Col = 1;
+  for (const auto *S : Segments) {
+    unsigned End = std::min(S->Col, static_cast<unsigned>(Line.size()) + 1);
+    colored_ostream(OS, Highlight ? *Highlight : raw_ostream::SAVEDCOLOR,
+                    Options.Colors && Highlight, /*Bold=*/false, /*BG=*/true)
+        << Line.substr(Col - 1, End - Col);
+    if (Options.Debug && Highlight)
+      HighlightedRanges.push_back(std::make_pair(Col, End));
+    Col = End;
+    if (Col == ExpansionCol)
+      Highlight = raw_ostream::CYAN;
+    else if (S->HasCount && S->Count == 0)
+      Highlight = raw_ostream::RED;
+    else
+      Highlight = None;
   }
 
   // Show the rest of the line
-  OS << Line.substr(Start - 1, Line.size() - Start + 1);
+  colored_ostream(OS, Highlight ? *Highlight : raw_ostream::SAVEDCOLOR,
+                  Options.Colors && Highlight, /*Bold=*/false, /*BG=*/true)
+      << Line.substr(Col - 1, Line.size() - Col + 1);
   OS << "\n";
 
   if (Options.Debug) {
-    for (const auto &Range : Ranges) {
-      errs() << "Highlighted line " << Range.Line << ", " << Range.ColumnStart
-             << " -> ";
-      if (Range.ColumnEnd == std::numeric_limits<unsigned>::max()) {
-        errs() << "?\n";
-      } else {
-        errs() << Range.ColumnEnd << "\n";
-      }
-    }
+    for (const auto &Range : HighlightedRanges)
+      errs() << "Highlighted line " << LineNumber << ", " << Range.first
+             << " -> " << Range.second << "\n";
+    if (Highlight)
+      errs() << "Highlighted line " << LineNumber << ", " << Col << " -> ?\n";
   }
 }
 
@@ -109,18 +109,20 @@ void SourceCoverageView::renderLineNumberColumn(raw_ostream &OS,
   OS.indent(LineNumberColumnWidth - Str.size()) << Str << '|';
 }
 
-void SourceCoverageView::renderRegionMarkers(raw_ostream &OS,
-                                             ArrayRef<RegionMarker> Regions) {
+void SourceCoverageView::renderRegionMarkers(
+    raw_ostream &OS, ArrayRef<const CoverageSegment *> Segments) {
   SmallString<32> Buffer;
   raw_svector_ostream BufferOS(Buffer);
 
   unsigned PrevColumn = 1;
-  for (const auto &Region : Regions) {
+  for (const auto *S : Segments) {
+    if (!S->IsRegionEntry)
+      continue;
     // Skip to the new region
-    if (Region.Column > PrevColumn)
-      OS.indent(Region.Column - PrevColumn);
-    PrevColumn = Region.Column + 1;
-    BufferOS << Region.ExecutionCount;
+    if (S->Col > PrevColumn)
+      OS.indent(S->Col - PrevColumn);
+    PrevColumn = S->Col + 1;
+    BufferOS << S->Count;
     StringRef Str = BufferOS.str();
     // Trim the execution count
     Str = Str.substr(0, std::min(Str.size(), (size_t)7));
@@ -130,87 +132,14 @@ void SourceCoverageView::renderRegionMarkers(raw_ostream &OS,
   }
   OS << "\n";
 
-  if (Options.Debug) {
-    for (const auto &Region : Regions) {
-      errs() << "Marker at " << Region.Line << ":" << Region.Column << " = "
-             << Region.ExecutionCount << "\n";
-    }
-  }
+  if (Options.Debug)
+    for (const auto *S : Segments)
+      errs() << "Marker at " << S->Line << ":" << S->Col << " = " << S->Count
+             << (S->IsRegionEntry ? "\n" : " (pop)\n");
 }
 
-/// \brief Insert a new highlighting range into the line's highlighting ranges
-/// Return line's new highlighting ranges in result.
-static void insertExpansionHighlightRange(
-    ArrayRef<SourceCoverageView::HighlightRange> Ranges,
-    unsigned Line, unsigned StartCol, unsigned EndCol,
-    SmallVectorImpl<SourceCoverageView::HighlightRange> &Result) {
-  auto RangeToInsert = SourceCoverageView::HighlightRange(
-      Line, StartCol, EndCol, SourceCoverageView::HighlightRange::Expanded);
-  Result.clear();
-  size_t I = 0;
-  auto E = Ranges.size();
-  for (; I < E; ++I) {
-    if (RangeToInsert.ColumnStart < Ranges[I].ColumnEnd) {
-      const auto &Range = Ranges[I];
-      bool NextRangeContainsInserted = false;
-      // If the next range starts before the inserted range, move the end of the
-      // next range to the start of the inserted range.
-      if (Range.ColumnStart < RangeToInsert.ColumnStart) {
-        if (RangeToInsert.ColumnStart != Range.ColumnStart)
-          Result.push_back(SourceCoverageView::HighlightRange(
-              Range.Line, Range.ColumnStart, RangeToInsert.ColumnStart,
-              Range.Kind));
-        // If the next range also ends after the inserted range, keep this range
-        // and create a new range that starts at the inserted range and ends
-        // at the next range later.
-        if (Range.ColumnEnd > RangeToInsert.ColumnEnd)
-          NextRangeContainsInserted = true;
-      }
-      if (!NextRangeContainsInserted) {
-        ++I;
-        // Ignore ranges that are contained in inserted range
-        while (I < E && RangeToInsert.contains(Ranges[I]))
-          ++I;
-      }
-      break;
-    }
-    Result.push_back(Ranges[I]);
-  }
-  Result.push_back(RangeToInsert);
-  // If the next range starts before the inserted range end, move the start
-  // of the next range to the end of the inserted range.
-  if (I < E && Ranges[I].ColumnStart < RangeToInsert.ColumnEnd) {
-    const auto &Range = Ranges[I];
-    if (RangeToInsert.ColumnEnd != Range.ColumnEnd)
-      Result.push_back(SourceCoverageView::HighlightRange(
-          Range.Line, RangeToInsert.ColumnEnd, Range.ColumnEnd, Range.Kind));
-    ++I;
-  }
-  // Add the remaining ranges that are located after the inserted range
-  for (; I < E; ++I)
-    Result.push_back(Ranges[I]);
-}
-
-template <typename T>
-ArrayRef<T> gatherLineItems(size_t &CurrentIdx, const std::vector<T> &Items,
-                            unsigned LineNo) {
-  auto PrevIdx = CurrentIdx;
-  auto E = Items.size();
-  while (CurrentIdx < E && Items[CurrentIdx].Line == LineNo)
-    ++CurrentIdx;
-  return ArrayRef<T>(Items.data() + PrevIdx, CurrentIdx - PrevIdx);
-}
-
-void SourceCoverageView::render(raw_ostream &OS, unsigned IndentLevel) {
-  SmallVector<HighlightRange, 8> AdjustedLineHighlightRanges;
-  size_t CurrentHighlightRange = 0;
-  size_t CurrentRegionMarker = 0;
-
-  line_iterator Lines(File, /*SkipBlanks=*/false);
-  // Advance the line iterator to the first line.
-  while (Lines.line_number() < LineOffset)
-    ++Lines;
-
+void SourceCoverageView::render(raw_ostream &OS, bool WholeFile,
+                                unsigned IndentLevel) {
   // The width of the leading columns
   unsigned CombinedColumnWidth =
       (Options.ShowLineStats ? LineCoverageColumnWidth + 1 : 0) +
@@ -228,66 +157,88 @@ void SourceCoverageView::render(raw_ostream &OS, unsigned IndentLevel) {
   auto NextISV = InstantiationSubViews.begin();
   auto EndISV = InstantiationSubViews.end();
 
-  for (size_t I = 0, E = LineStats.size(); I < E && !Lines.is_at_eof();
-       ++I, ++Lines) {
-    unsigned LineNo = Lines.line_number();
+  // Get the coverage information for the file.
+  auto CoverageSegments = RegionManager->getCoverageSegments();
+  assert(CoverageSegments.size() && "View with no coverage?");
+  auto NextSegment = CoverageSegments.begin();
+  auto EndSegment = CoverageSegments.end();
+
+  const CoverageSegment *WrappedSegment = nullptr;
+  SmallVector<const CoverageSegment *, 8> LineSegments;
+  for (line_iterator LI(File, /*SkipBlanks=*/false); !LI.is_at_eof(); ++LI) {
+    // If we aren't rendering the whole file, we need to filter out the prologue
+    // and epilogue.
+    if (!WholeFile) {
+      if (NextSegment == EndSegment)
+        break;
+      else if (LI.line_number() < NextSegment->Line)
+        continue;
+    }
 
+    // Collect the coverage information relevant to this line.
+    if (LineSegments.size())
+      WrappedSegment = LineSegments.back();
+    LineSegments.clear();
+    while (NextSegment != EndSegment && NextSegment->Line == LI.line_number())
+      LineSegments.push_back(&*NextSegment++);
+
+    // Calculate a count to be for the line as a whole.
+    LineCoverageInfo LineCount;
+    if (WrappedSegment && WrappedSegment->HasCount)
+      LineCount.addRegionCount(WrappedSegment->Count);
+    for (const auto *S : LineSegments)
+      if (S->HasCount && S->IsRegionEntry)
+          LineCount.addRegionStartCount(S->Count);
+
+    // Render the line prefix.
     renderIndent(OS, IndentLevel);
     if (Options.ShowLineStats)
-      renderLineCoverageColumn(OS, LineStats[I]);
+      renderLineCoverageColumn(OS, LineCount);
     if (Options.ShowLineNumbers)
-      renderLineNumberColumn(OS, LineNo);
+      renderLineNumberColumn(OS, LI.line_number());
 
-    // Gather highlighting ranges.
-    auto LineHighlightRanges =
-        gatherLineItems(CurrentHighlightRange, HighlightRanges, LineNo);
-    auto LineRanges = LineHighlightRanges;
-    // Highlight the expansion range if there is an expansion subview on this
-    // line.
-    if (NextESV != EndESV && NextESV->getLine() == LineNo && Options.Colors) {
-      insertExpansionHighlightRange(
-          LineHighlightRanges, NextESV->getLine(), NextESV->getStartCol(),
-          NextESV->getEndCol(), AdjustedLineHighlightRanges);
-      LineRanges = AdjustedLineHighlightRanges;
-    }
+    // If there are expansion subviews, we want to highlight the first one.
+    unsigned ExpansionColumn = 0;
+    if (NextESV != EndESV && NextESV->getLine() == LI.line_number() &&
+        Options.Colors)
+      ExpansionColumn = NextESV->getStartCol();
 
     // Display the source code for the current line.
-    StringRef Line = *Lines;
-    renderLine(OS, Line, LineRanges);
+    renderLine(OS, *LI, LI.line_number(), WrappedSegment, LineSegments,
+               ExpansionColumn);
 
     // Show the region markers.
-    bool ShowMarkers = !Options.ShowLineStatsOrRegionMarkers ||
-                       LineStats[I].hasMultipleRegions();
-    auto LineMarkers = gatherLineItems(CurrentRegionMarker, Markers, LineNo);
-    if (ShowMarkers && !LineMarkers.empty()) {
+    if (Options.ShowRegionMarkers && (!Options.ShowLineStatsOrRegionMarkers ||
+                                      LineCount.hasMultipleRegions()) &&
+        !LineSegments.empty()) {
       renderIndent(OS, IndentLevel);
       OS.indent(CombinedColumnWidth);
-      renderRegionMarkers(OS, LineMarkers);
+      renderRegionMarkers(OS, LineSegments);
     }
 
     // Show the expansions and instantiations for this line.
     unsigned NestedIndent = IndentLevel + 1;
     bool RenderedSubView = false;
-    for (; NextESV != EndESV && NextESV->getLine() == LineNo; ++NextESV) {
+    for (; NextESV != EndESV && NextESV->getLine() == LI.line_number();
+         ++NextESV) {
       renderViewDivider(NestedIndent, DividerWidth, OS);
       OS << "\n";
       if (RenderedSubView) {
         // Re-render the current line and highlight the expansion range for
         // this subview.
-        insertExpansionHighlightRange(
-            LineHighlightRanges, NextESV->getLine(), NextESV->getStartCol(),
-            NextESV->getEndCol(), AdjustedLineHighlightRanges);
+        ExpansionColumn = NextESV->getStartCol();
         renderIndent(OS, IndentLevel);
         OS.indent(CombinedColumnWidth + (IndentLevel == 0 ? 0 : 1));
-        renderLine(OS, Line, AdjustedLineHighlightRanges);
+        renderLine(OS, *LI, LI.line_number(), WrappedSegment, LineSegments,
+                   ExpansionColumn);
         renderViewDivider(NestedIndent, DividerWidth, OS);
         OS << "\n";
       }
       // Render the child subview
-      NextESV->View->render(OS, NestedIndent);
+      NextESV->View->render(OS, false, NestedIndent);
       RenderedSubView = true;
     }
-    for (; NextISV != EndISV && NextISV->Line == LineNo; ++NextISV) {
+    for (; NextISV != EndISV && NextISV->Line == LI.line_number(); ++NextISV) {
       renderViewDivider(NestedIndent, DividerWidth, OS);
       OS << "\n";
       renderIndent(OS, NestedIndent);
@@ -295,7 +246,7 @@ void SourceCoverageView::render(raw_ostream &OS, unsigned IndentLevel) {
       Options.colored_ostream(OS, raw_ostream::CYAN) << NextISV->FunctionName
                                                      << ":";
       OS << "\n";
-      NextISV->View->render(OS, NestedIndent);
+      NextISV->View->render(OS, false, NestedIndent);
       RenderedSubView = true;
     }
     if (RenderedSubView) {
@@ -304,89 +255,3 @@ void SourceCoverageView::render(raw_ostream &OS, unsigned IndentLevel) {
     }
   }
 }
-
-void SourceCoverageView::setUpVisibleRange(SourceCoverageDataManager &Data) {
-  auto CountedRegions = Data.getSourceRegions();
-  if (!CountedRegions.size())
-    return;
-
-  unsigned Start = CountedRegions.front().LineStart, End = 0;
-  for (const auto &CR : CountedRegions) {
-    Start = std::min(Start, CR.LineStart);
-    End = std::max(End, CR.LineEnd);
-  }
-  LineOffset = Start;
-  LineStats.resize(End - Start + 1);
-}
-
-void
-SourceCoverageView::createLineCoverageInfo(SourceCoverageDataManager &Data) {
-  auto CountedRegions = Data.getSourceRegions();
-  for (const auto &CR : CountedRegions) {
-    if (CR.Kind == coverage::CounterMappingRegion::SkippedRegion) {
-      // Reset the line stats for skipped regions.
-      for (unsigned Line = CR.LineStart; Line <= CR.LineEnd;
-           ++Line)
-        LineStats[Line - LineOffset] = LineCoverageInfo();
-      continue;
-    }
-    LineStats[CR.LineStart - LineOffset].addRegionStartCount(CR.ExecutionCount);
-    for (unsigned Line = CR.LineStart + 1; Line <= CR.LineEnd; ++Line)
-      LineStats[Line - LineOffset].addRegionCount(CR.ExecutionCount);
-  }
-}
-
-void
-SourceCoverageView::createHighlightRanges(SourceCoverageDataManager &Data) {
-  auto CountedRegions = Data.getSourceRegions();
-  std::vector<bool> AlreadyHighlighted;
-  AlreadyHighlighted.resize(CountedRegions.size(), false);
-
-  for (size_t I = 0, S = CountedRegions.size(); I < S; ++I) {
-    const auto &CR = CountedRegions[I];
-    if (CR.Kind == coverage::CounterMappingRegion::SkippedRegion ||
-        CR.ExecutionCount != 0)
-      continue;
-    if (AlreadyHighlighted[I])
-      continue;
-    for (size_t J = 0; J < S; ++J) {
-      if (CR.contains(CountedRegions[J])) {
-        AlreadyHighlighted[J] = true;
-      }
-    }
-    if (CR.LineStart == CR.LineEnd) {
-      HighlightRanges.push_back(HighlightRange(
-          CR.LineStart, CR.ColumnStart, CR.ColumnEnd));
-      continue;
-    }
-    HighlightRanges.push_back(
-        HighlightRange(CR.LineStart, CR.ColumnStart,
-                       std::numeric_limits<unsigned>::max()));
-    HighlightRanges.push_back(
-        HighlightRange(CR.LineEnd, 1, CR.ColumnEnd));
-    for (unsigned Line = CR.LineStart + 1; Line < CR.LineEnd;
-         ++Line) {
-      HighlightRanges.push_back(
-          HighlightRange(Line, 1, std::numeric_limits<unsigned>::max()));
-    }
-  }
-
-  std::sort(HighlightRanges.begin(), HighlightRanges.end());
-}
-
-void SourceCoverageView::createRegionMarkers(SourceCoverageDataManager &Data) {
-  for (const auto &CR : Data.getSourceRegions())
-    if (CR.Kind != coverage::CounterMappingRegion::SkippedRegion)
-      Markers.push_back(
-          RegionMarker(CR.LineStart, CR.ColumnStart, CR.ExecutionCount));
-}
-
-void SourceCoverageView::load(SourceCoverageDataManager &Data) {
-  setUpVisibleRange(Data);
-  if (Options.ShowLineStats)
-    createLineCoverageInfo(Data);
-  if (Options.Colors)
-    createHighlightRanges(Data);
-  if (Options.ShowRegionMarkers)
-    createRegionMarkers(Data);
-}