Commit 31d375f1 authored by Fangrui Song's avatar Fangrui Song
Browse files

CGDebugInfo: Drop Loc.isInvalid() special case from getLineNumber 

`getLineNumber()` picks CurLoc if the parameter is invalid. This appears to
mainly work around missing SourceLocation information for some constructs, but
sometimes adds unintended locations.

* For `CodeGenObjC/debug-info-blocks.m`, `CurLoc` has been advanced to the closing brace. The debug line of `ImplicitVarParameter` is set to the line of `}` because this implicit parameter has an invalid `SourceLocation`. The debug line is a bit arbitrary - perhaps the location of `^{` is better.
* The file/line of Clang synthesized `__va_list_tag` is arbitrarily attached a `#include` line. D94735

Drop the special case to make getLineNumber less magic and add CurLoc fallback in its callers instead.

Tested with stage 2 -DCMAKE_BUILD_TYPE=Debug clang, byte identical.

Reviewed By: #debug-info, aprantl

Differential Revision: https://reviews.llvm.org/D94391
parent 2291bd13

clang/lib/CodeGen/CGDebugInfo.cpp

+12 −8
Original line number Diff line number Diff line
@@ -481,11 +481,10 @@ std::string CGDebugInfo::remapDIPath(StringRef Path) const { 
}



unsigned CGDebugInfo::getLineNumber(SourceLocation Loc) {

  if (Loc.isInvalid() && CurLoc.isInvalid())

  if (Loc.isInvalid())

    return 0;

  SourceManager &SM = CGM.getContext().getSourceManager();

  PresumedLoc PLoc = SM.getPresumedLoc(Loc.isValid() ? Loc : CurLoc);

  return PLoc.isValid() ? PLoc.getLine() : 0;

  return SM.getPresumedLoc(Loc).getLine();

}



unsigned CGDebugInfo::getColumnNumber(SourceLocation Loc, bool Force) {
@@ -1025,7 +1024,8 @@ CGDebugInfo::getOrCreateRecordFwdDecl(const RecordType *Ty, 
  if (llvm::DIType *T = getTypeOrNull(CGM.getContext().getRecordType(RD)))

    return cast<llvm::DICompositeType>(T);

  llvm::DIFile *DefUnit = getOrCreateFile(RD->getLocation());

  unsigned Line = getLineNumber(RD->getLocation());

  const unsigned Line =

      getLineNumber(RD->getLocation().isValid() ? RD->getLocation() : CurLoc);

  StringRef RDName = getClassName(RD);



  uint64_t Size = 0;
@@ -1349,7 +1349,7 @@ CGDebugInfo::createFieldType(StringRef name, QualType type, SourceLocation loc, 


  // Get the location for the field.

  llvm::DIFile *file = getOrCreateFile(loc);

  unsigned line = getLineNumber(loc);

  const unsigned line = getLineNumber(loc.isValid() ? loc : CurLoc);



  uint64_t SizeInBits = 0;

  auto Align = AlignInBits;
@@ -3333,7 +3333,8 @@ llvm::DICompositeType *CGDebugInfo::CreateLimitedType(const RecordType *Ty) { 


  // Get overall information about the record type for the debug info.

  llvm::DIFile *DefUnit = getOrCreateFile(RD->getLocation());

  unsigned Line = getLineNumber(RD->getLocation());

  const unsigned Line =

      getLineNumber(RD->getLocation().isValid() ? RD->getLocation() : CurLoc);

  StringRef RDName = getClassName(RD);



  llvm::DIScope *RDContext = getDeclContextDescriptor(RD);
@@ -3869,7 +3870,7 @@ void CGDebugInfo::emitFunctionStart(GlobalDecl GD, SourceLocation Loc, 
  llvm::DISubprogram::DISPFlags SPFlagsForDef =

      SPFlags | llvm::DISubprogram::SPFlagDefinition;



  unsigned LineNo = getLineNumber(Loc);

  const unsigned LineNo = getLineNumber(Loc.isValid() ? Loc : CurLoc);

  unsigned ScopeLine = getLineNumber(ScopeLoc);

  llvm::DISubroutineType *DIFnType = getOrCreateFunctionType(D, FnType, Unit);

  llvm::DISubprogram *Decl = nullptr;
@@ -4372,7 +4373,8 @@ void CGDebugInfo::EmitDeclareOfBlockDeclRefVariable( 
      Ty = CreateSelfType(VD->getType(), Ty);



  // Get location information.

  unsigned Line = getLineNumber(VD->getLocation());

  const unsigned Line =

      getLineNumber(VD->getLocation().isValid() ? VD->getLocation() : CurLoc);

  unsigned Column = getColumnNumber(VD->getLocation());



  const llvm::DataLayout &target = CGM.getDataLayout();
@@ -4832,6 +4834,8 @@ void CGDebugInfo::EmitUsingDirective(const UsingDirectiveDecl &UD) { 
  if (!NSDecl->isAnonymousNamespace() ||

      CGM.getCodeGenOpts().DebugExplicitImport) {

    auto Loc = UD.getLocation();

    if (!Loc.isValid())

      Loc = CurLoc;

    DBuilder.createImportedModule(

        getCurrentContextDescriptor(cast<Decl>(UD.getDeclContext())),

        getOrCreateNamespace(NSDecl), getOrCreateFile(Loc), getLineNumber(Loc));