Revert abd45154b "[Coverage] Add comment to skipped regions"

This casued assertions during Chromium builds. See comment on the code review

> Bug filled here: https://bugs.llvm.org/show_bug.cgi?id=45757.
> Add comment to skipped regions so we don't track execution count for lines containing only comments.
>
> Differential Revision: https://reviews.llvm.org/D84208

This reverts commit abd45154bdb6b76c5b480455eacc8c75b08242aa and the
follow-up 87d725473380652bbe845fd2fbd9c0507a55172f.

1 files changed, 5 insertions, 69 deletions

diff --git a/clang/lib/CodeGen/CoverageMappingGen.cpp b/clang/lib/CodeGen/CoverageMappingGen.cpp
index 6729c7f..78b268f 100644
--- a/clang/lib/CodeGen/CoverageMappingGen.cpp
+++ b/clang/lib/CodeGen/CoverageMappingGen.cpp
@@ -35,40 +35,8 @@ using namespace clang;
 using namespace CodeGen;
 using namespace llvm::coverage;
 
-CoverageSourceInfo *
-CoverageMappingModuleGen::setUpCoverageCallbacks(Preprocessor &PP) {
-  CoverageSourceInfo *CoverageInfo = new CoverageSourceInfo;
-  PP.addPPCallbacks(std::unique_ptr<PPCallbacks>(CoverageInfo));
-  PP.addCommentHandler(CoverageInfo);
-  PP.setPreprocessToken(true);
-  PP.setTokenWatcher([CoverageInfo](clang::Token Tok) {
-    // Update previous token location.
-    CoverageInfo->PrevTokLoc = Tok.getLocation();
-    CoverageInfo->updateNextTokLoc(Tok.getLocation());
-  });
-  return CoverageInfo;
-}
-
 void CoverageSourceInfo::SourceRangeSkipped(SourceRange Range, SourceLocation) {
-  SkippedRanges.push_back({Range});
-}
-
-bool CoverageSourceInfo::HandleComment(Preprocessor &PP, SourceRange Range) {
-  if (PrevTokLoc.isValid() && PrevTokLoc == BeforeCommentLoc)
-    SkippedRanges.back().Range.setEnd(Range.getEnd());
-  else {
-    SkippedRanges.push_back({Range, PrevTokLoc});
-    BeforeCommentLoc = PrevTokLoc;
-  }
-  LastCommentIndex = SkippedRanges.size() - 1;
-  return false;
-}
-
-void CoverageSourceInfo::updateNextTokLoc(SourceLocation Loc) {
-  if (LastCommentIndex) {
-    SkippedRanges[LastCommentIndex.getValue()].NextTokLoc = Loc;
-    LastCommentIndex = None;
-  }
+  SkippedRanges.push_back(Range);
 }
 
 namespace {
@@ -306,34 +274,8 @@ public:
     return None;
   }
 
-  /// This shrinks the skipped range if it spans a line that contains a
-  /// non-comment token. If shrinking the skipped range would make it empty,
-  /// this returns None.
-  Optional<SpellingRegion> adjustSkippedRange(SourceManager &SM,
-                                              SpellingRegion SR,
-                                              SourceLocation PrevTokLoc,
-                                              SourceLocation NextTokLoc) {
-    // If Range begin location is invalid, it's not a comment region.
-    if (PrevTokLoc.isInvalid())
-      return SR;
-    unsigned PrevTokLine = SM.getSpellingLineNumber(PrevTokLoc);
-    unsigned NextTokLine = SM.getSpellingLineNumber(NextTokLoc);
-    SpellingRegion newSR(SR);
-    if (SR.LineStart == PrevTokLine) {
-      newSR.LineStart = SR.LineStart + 1;
-      newSR.ColumnStart = 1;
-    }
-    if (SR.LineEnd == NextTokLine) {
-      newSR.LineEnd = SR.LineEnd - 1;
-      newSR.ColumnEnd = 1;
-    }
-    if (newSR.isInSourceOrder())
-      return newSR;
-    return None;
-  }
-
   /// Gather all the regions that were skipped by the preprocessor
-  /// using the constructs like #if or comments.
+  /// using the constructs like #if.
   void gatherSkippedRegions() {
     /// An array of the minimum lineStarts and the maximum lineEnds
     /// for mapping regions from the appropriate source files.
@@ -349,10 +291,9 @@ public:
     }
 
     auto SkippedRanges = CVM.getSourceInfo().getSkippedRanges();
-    for (auto &I : SkippedRanges) {
-      SourceRange Range = I.Range;
-      auto LocStart = Range.getBegin();
-      auto LocEnd = Range.getEnd();
+    for (const auto &I : SkippedRanges) {
+      auto LocStart = I.getBegin();
+      auto LocEnd = I.getEnd();
       assert(SM.isWrittenInSameFile(LocStart, LocEnd) &&
              "region spans multiple files");
 
@@ -360,11 +301,6 @@ public:
       if (!CovFileID)
         continue;
       SpellingRegion SR{SM, LocStart, LocEnd};
-      if (Optional<SpellingRegion> res =
-              adjustSkippedRange(SM, SR, I.PrevTokLoc, I.NextTokLoc))
-        SR = res.getValue();
-      else
-        continue;
       auto Region = CounterMappingRegion::makeSkipped(
           *CovFileID, SR.LineStart, SR.ColumnStart, SR.LineEnd, SR.ColumnEnd);
       // Make sure that we only collect the regions that are inside