InstrProf: Remove CoverageMapping::HasCodeBefore, it isn't used

It's not entirely clear to me what this field was meant for, but it's
always false. Remove it.

llvm-svn: 228034
diff --git a/llvm/lib/ProfileData/CoverageMappingReader.cpp b/llvm/lib/ProfileData/CoverageMappingReader.cpp
index 71ce22a..423947d 100644
--- a/llvm/lib/ProfileData/CoverageMappingReader.cpp
+++ b/llvm/lib/ProfileData/CoverageMappingReader.cpp
@@ -173,15 +173,12 @@
     }
 
     // Read the source range.
-    uint64_t LineStartDelta, CodeBeforeColumnStart, NumLines, ColumnEnd;
+    uint64_t LineStartDelta, ColumnStart, NumLines, ColumnEnd;
     if (auto Err =
             readIntMax(LineStartDelta, std::numeric_limits<unsigned>::max()))
       return Err;
-    if (auto Err = readULEB128(CodeBeforeColumnStart))
+    if (auto Err = readULEB128(ColumnStart))
       return Err;
-    bool HasCodeBefore = CodeBeforeColumnStart & 1;
-    uint64_t ColumnStart = CodeBeforeColumnStart >>
-                           CounterMappingRegion::EncodingHasCodeBeforeBits;
     if (ColumnStart > std::numeric_limits<unsigned>::max())
       return error(instrprof_error::malformed);
     if (auto Err = readIntMax(NumLines, std::numeric_limits<unsigned>::max()))
@@ -213,9 +210,9 @@
       dbgs() << "\n";
     });
 
-    MappingRegions.push_back(CounterMappingRegion(
-        C, InferredFileID, LineStart, ColumnStart, LineStart + NumLines,
-        ColumnEnd, HasCodeBefore, Kind));
+    MappingRegions.push_back(
+        CounterMappingRegion(C, InferredFileID, LineStart, ColumnStart,
+                             LineStart + NumLines, ColumnEnd, Kind));
     MappingRegions.back().ExpandedFileID = ExpandedFileID;
   }
   return success();