4 files changed, 24 insertions, 35 deletions

diff --git a/llvm/lib/MC/MCContext.cpp b/llvm/lib/MC/MCContext.cpp
index 0a13c9e6edb..bbff9b7c6a5 100644
--- a/llvm/lib/MC/MCContext.cpp
+++ b/llvm/lib/MC/MCContext.cpp
@@ -77,7 +77,7 @@ void MCContext::reset() {
   CompilationDir.clear();
   MainFileName.clear();
   MCDwarfLineTablesCUMap.clear();
-  SectionStartEndSyms.clear();
+  SectionsForRanges.clear();
   MCGenDwarfLabelEntries.clear();
   DwarfDebugFlags = StringRef();
   DwarfCompileUnitID = 0;
@@ -437,27 +437,17 @@ bool MCContext::isValidDwarfFileNumber(unsigned FileNumber, unsigned CUID) {
   return !MCDwarfFiles[FileNumber].Name.empty();
 }
 
-/// finalizeDwarfSections - Emit end symbols for each non-empty code section.
-/// Also remove empty sections from SectionStartEndSyms, to avoid generating
+/// Remove empty sections from SectionStartEndSyms, to avoid generating
 /// useless debug info for them.
 void MCContext::finalizeDwarfSections(MCStreamer &MCOS) {
-  MCContext &context = MCOS.getContext();
-
-  auto sec = SectionStartEndSyms.begin();
-  while (sec != SectionStartEndSyms.end()) {
-    assert(sec->second.first && "Start symbol must be set by now");
-    MCOS.SwitchSection(sec->first);
-    if (MCOS.mayHaveInstructions()) {
-      MCSymbol *SectionEndSym = context.createTempSymbol();
-      MCOS.EmitLabel(SectionEndSym);
-      sec->second.second = SectionEndSym;
-      ++sec;
-    } else {
-      MapVector<const MCSection *, std::pair<MCSymbol *, MCSymbol *>>::iterator
-          to_erase = sec;
-      sec = SectionStartEndSyms.erase(to_erase);
-    }
+  std::vector<const MCSection *> Keep;
+  for (const MCSection *Sec : SectionsForRanges) {
+    MCOS.SwitchSection(Sec); // FIXME: pass the section to mayHaveInstructions
+    if (MCOS.mayHaveInstructions())
+      Keep.push_back(Sec);
   }
+  SectionsForRanges.clear();
+  SectionsForRanges.insert(Keep.begin(), Keep.end());
 }
 
 void MCContext::reportFatalError(SMLoc Loc, const Twine &Msg) const {
diff --git a/llvm/lib/MC/MCDwarf.cpp b/llvm/lib/MC/MCDwarf.cpp
index 74eee83b73f..ad70d61dccb 100644
--- a/llvm/lib/MC/MCDwarf.cpp
+++ b/llvm/lib/MC/MCDwarf.cpp
@@ -610,9 +610,9 @@ static void EmitGenDwarfAranges(MCStreamer *MCOS,
 
   // Now emit the table of pairs of PointerSize'ed values for the section
   // addresses and sizes.
-  for (const auto &sec : Sections) {
-    MCSymbol *StartSymbol = sec.second.first;
-    MCSymbol *EndSymbol = sec.second.second;
+  for (const MCSection *Sec : Sections) {
+    MCSymbol *StartSymbol = Sec->getBeginSymbol();
+    MCSymbol *EndSymbol = Sec->getEndSymbol(context);
     assert(StartSymbol && "StartSymbol must not be NULL");
     assert(EndSymbol && "EndSymbol must not be NULL");
 
@@ -699,8 +699,8 @@ static void EmitGenDwarfInfo(MCStreamer *MCOS,
     const auto TextSection = Sections.begin();
     assert(TextSection != Sections.end() && "No text section found");
 
-    MCSymbol *StartSymbol = TextSection->second.first;
-    MCSymbol *EndSymbol = TextSection->second.second;
+    MCSymbol *StartSymbol = (*TextSection)->getBeginSymbol();
+    MCSymbol *EndSymbol = (*TextSection)->getEndSymbol(context);
     assert(StartSymbol && "StartSymbol must not be NULL");
     assert(EndSymbol && "EndSymbol must not be NULL");
 
@@ -805,10 +805,9 @@ static void EmitGenDwarfRanges(MCStreamer *MCOS) {
 
   MCOS->SwitchSection(context.getObjectFileInfo()->getDwarfRangesSection());
 
-  for (const auto &sec : Sections) {
-
-    MCSymbol *StartSymbol = sec.second.first;
-    MCSymbol *EndSymbol = sec.second.second;
+  for (const MCSection *Sec : Sections) {
+    MCSymbol *StartSymbol = Sec->getBeginSymbol();
+    MCSymbol *EndSymbol = Sec->getEndSymbol(context);
     assert(StartSymbol && "StartSymbol must not be NULL");
     assert(EndSymbol && "EndSymbol must not be NULL");
 
diff --git a/llvm/lib/MC/MCParser/AsmParser.cpp b/llvm/lib/MC/MCParser/AsmParser.cpp
index 5b5cc5fae2a..da3fc72057e 100644
--- a/llvm/lib/MC/MCParser/AsmParser.cpp
+++ b/llvm/lib/MC/MCParser/AsmParser.cpp
@@ -632,10 +632,10 @@ bool AsmParser::Run(bool NoInitialTextSection, bool NoFinalize) {
   if (getContext().getGenDwarfForAssembly()) {
     MCSymbol *SectionStartSym = getContext().createTempSymbol();
     getStreamer().EmitLabel(SectionStartSym);
-    auto InsertResult = getContext().addGenDwarfSection(
-        getStreamer().getCurrentSection().first);
-    assert(InsertResult.second && ".text section should not have debug info yet");
-    InsertResult.first->second.first = SectionStartSym;
+    const MCSection *Sec = getStreamer().getCurrentSection().first;
+    bool InsertResult = getContext().addGenDwarfSection(Sec);
+    assert(InsertResult && ".text section should not have debug info yet");
+    Sec->setBeginSymbol(SectionStartSym);
     getContext().setGenDwarfFileNumber(getStreamer().EmitDwarfFileDirective(
         0, StringRef(), getContext().getMainFileName()));
   }
diff --git a/llvm/lib/MC/MCParser/ELFAsmParser.cpp b/llvm/lib/MC/MCParser/ELFAsmParser.cpp
index d99a6c4836b..6b0a7785517 100644
--- a/llvm/lib/MC/MCParser/ELFAsmParser.cpp
+++ b/llvm/lib/MC/MCParser/ELFAsmParser.cpp
@@ -532,14 +532,14 @@ EndStmt:
   getStreamer().SwitchSection(ELFSection, Subsection);
 
   if (getContext().getGenDwarfForAssembly()) {
-    auto InsertResult = getContext().addGenDwarfSection(ELFSection);
-    if (InsertResult.second) {
+    bool InsertResult = getContext().addGenDwarfSection(ELFSection);
+    if (InsertResult) {
       if (getContext().getDwarfVersion() <= 2)
         Warning(loc, "DWARF2 only supports one section per compilation unit");
 
       MCSymbol *SectionStartSymbol = getContext().createTempSymbol();
       getStreamer().EmitLabel(SectionStartSymbol);
-      InsertResult.first->second.first = SectionStartSymbol;
+      ELFSection->setBeginSymbol(SectionStartSymbol);
     }
   }