[llvm] r227017 - llvm-cov: Only combine segments if they overlap exactly

[Justin Bogner]

Author: bogner
Date: Sat Jan 24 14:58:52 2015
New Revision: 227017

URL: http://llvm.org/viewvc/llvm-project?rev=227017&view=rev
Log:
llvm-cov: Only combine segments if they overlap exactly

If two coverage segments cover the same area we need to combine them,
as per r218432. OTOH, just because they start at the same place
doesn't mean they cover the same area. This fixes the check to be more
exact about this.

This is pretty hard to test right now. The frontend doesn't currently
emit regions that start at the same place but don't overlap, but some
upcoming work changes this.

Modified:
    llvm/trunk/lib/ProfileData/CoverageMapping.cpp

Modified: llvm/trunk/lib/ProfileData/CoverageMapping.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/ProfileData/CoverageMapping.cpp?rev=227017&r1=227016&r2=227017&view=diff
==============================================================================
--- llvm/trunk/lib/ProfileData/CoverageMapping.cpp (original)
+++ llvm/trunk/lib/ProfileData/CoverageMapping.cpp Sat Jan 24 14:58:52 2015
@@ -304,13 +304,14 @@ class SegmentBuilder {
 public:
   /// Build a list of CoverageSegments from a sorted list of Regions.
   std::vector<CoverageSegment> buildSegments(ArrayRef<CountedRegion> Regions) {
+    const CountedRegion *PrevRegion = nullptr;
     for (const auto &Region : Regions) {
       // Pop any regions that end before this one starts.
       while (!ActiveRegions.empty() &&
              ActiveRegions.back()->endLoc() <= Region.startLoc())
         popRegion();
-      if (!Segments.empty() && Segments.back().Line == Region.LineStart &&
-          Segments.back().Col == Region.ColumnStart) {
+      if (PrevRegion && PrevRegion->startLoc() == Region.startLoc() &&
+          PrevRegion->endLoc() == Region.endLoc()) {
         if (Region.Kind != coverage::CounterMappingRegion::SkippedRegion)
           Segments.back().addCount(Region.ExecutionCount);
       } else {
@@ -318,6 +319,7 @@ public:
         ActiveRegions.push_back(&Region);
         startSegment(Region);
       }
+      PrevRegion = &Region;
     }
     // Pop any regions that are left in the stack.
     while (!ActiveRegions.empty())
@@ -409,6 +411,7 @@ CoverageData CoverageMapping::getCoverag
   }
 
   sortNestedRegions(Regions.begin(), Regions.end());
+  DEBUG(dbgs() << "Emitting segments for file: " << Filename << "\n");
   FileCoverage.Segments = SegmentBuilder().buildSegments(Regions);
 
   return FileCoverage;
@@ -450,6 +453,7 @@ CoverageMapping::getCoverageForFunction(
     }
 
   sortNestedRegions(Regions.begin(), Regions.end());
+  DEBUG(dbgs() << "Emitting segments for function: " << Function.Name << "\n");
   FunctionCoverage.Segments = SegmentBuilder().buildSegments(Regions);
 
   return FunctionCoverage;
@@ -468,6 +472,8 @@ CoverageMapping::getCoverageForExpansion
     }
 
   sortNestedRegions(Regions.begin(), Regions.end());
+  DEBUG(dbgs() << "Emitting segments for expansion of file " << Expansion.FileID
+               << "\n");
   ExpansionCoverage.Segments = SegmentBuilder().buildSegments(Regions);
 
   return ExpansionCoverage;