4 files changed, 24 insertions, 9 deletions
diff --git a/llvm/lib/CodeGen/AsmPrinter/AsmPrinter.cpp b/llvm/lib/CodeGen/AsmPrinter/AsmPrinter.cpp
index e66237706bc..de08b77012b 100644
--- a/llvm/lib/CodeGen/AsmPrinter/AsmPrinter.cpp
+++ b/llvm/lib/CodeGen/AsmPrinter/AsmPrinter.cpp
@@ -292,6 +292,9 @@ void AsmPrinter::EmitGlobalVariable(const GlobalVariable *GV) {
   // sections and expected to be contiguous (e.g. ObjC metadata).
   unsigned AlignLog = getGVAlignmentLog2(GV, *TD);
 
+  if (DD)
+    DD->setSymbolSize(GVSym, Size);
+
   // Handle common and BSS local symbols (.lcomm).
   if (GVKind.isCommon() || GVKind.isBSSLocal()) {
     if (Size == 0) Size = 1;   // .comm Foo, 0 is undefined, avoid it.
diff --git a/llvm/lib/CodeGen/AsmPrinter/DwarfDebug.cpp b/llvm/lib/CodeGen/AsmPrinter/DwarfDebug.cpp
index 6414969774b..48a7c185ec2 100644
--- a/llvm/lib/CodeGen/AsmPrinter/DwarfDebug.cpp
+++ b/llvm/lib/CodeGen/AsmPrinter/DwarfDebug.cpp
@@ -2838,12 +2838,17 @@ void DwarfDebug::emitDebugARanges() {
       Asm->EmitLabelReference(Span.Start, PtrSize);
 
       // Calculate the size as being from the span start to it's end.
-      // If we have no valid end symbol, then we just cover the first byte.
-      // (this sucks, but I can't seem to figure out how to get the size)
-      if (Span.End)
+      if (Span.End) {
         Asm->EmitLabelDifference(Span.End, Span.Start, PtrSize);
-      else
-        Asm->OutStreamer.EmitIntValue(1, PtrSize);
+      } else {
+        // For symbols without an end marker (e.g. common), we
+        // write a single arange entry containing just that one symbol.
+        uint64_t Size = SymSize[Span.Start];
+        if (Size == 0)
+          Size = 1;
+
+        Asm->OutStreamer.EmitIntValue(Size, PtrSize);
+      }
     }
 
     Asm->OutStreamer.AddComment("ARange terminator");
diff --git a/llvm/lib/CodeGen/AsmPrinter/DwarfDebug.h b/llvm/lib/CodeGen/AsmPrinter/DwarfDebug.h
index 8fe60c77be5..e774c653945 100644
--- a/llvm/lib/CodeGen/AsmPrinter/DwarfDebug.h
+++ b/llvm/lib/CodeGen/AsmPrinter/DwarfDebug.h
@@ -341,6 +341,9 @@ class DwarfDebug {
   // List of all labels used in the output.
   std::vector<SymbolCU> Labels;
 
+  // Size of each symbol emitted (for those symbols that have a specific size).
+  DenseMap <const MCSymbol *, uint64_t> SymSize;
+
   // Provides a unique id per text section.
   typedef DenseMap<const MCSection *, SmallVector<SymbolCU, 8> > SectionMapType;
   SectionMapType SectionMap;
@@ -682,6 +685,10 @@ public:
   /// \brief Add a label so that arange data can be generated for it.
   void addLabel(SymbolCU SCU) { Labels.push_back(SCU); }
 
+  /// \brief For symbols that have a size designated (e.g. common symbols),
+  /// this tracks that size.
+  void setSymbolSize(const MCSymbol *Sym, uint64_t Size) { SymSize[Sym] = Size;}
+
   /// \brief Look up the source id with the given directory and source file
   /// names. If none currently exists, create a new id and insert it in the
   /// SourceIds map.
diff --git a/llvm/lib/MC/MCAsmStreamer.cpp b/llvm/lib/MC/MCAsmStreamer.cpp
index e57025e1019..80b0acec846 100644
--- a/llvm/lib/MC/MCAsmStreamer.cpp
+++ b/llvm/lib/MC/MCAsmStreamer.cpp
@@ -533,8 +533,8 @@ void MCAsmStreamer::EmitELFSize(MCSymbol *Symbol, const MCExpr *Value) {
 
 void MCAsmStreamer::EmitCommonSymbol(MCSymbol *Symbol, uint64_t Size,
                                      unsigned ByteAlignment) {
-  const MCSection *Section = getContext().getObjectFileInfo()->getBSSSection();
-  AssignSection(Symbol, Section);
+  // Common symbols do not belong to any actual section.
+  AssignSection(Symbol, NULL);
 
   OS << "\t.comm\t" << *Symbol << ',' << Size;
   if (ByteAlignment != 0) {
@@ -552,8 +552,8 @@ void MCAsmStreamer::EmitCommonSymbol(MCSymbol *Symbol, uint64_t Size,
 /// @param Size - The size of the common symbol.
 void MCAsmStreamer::EmitLocalCommonSymbol(MCSymbol *Symbol, uint64_t Size,
                                           unsigned ByteAlign) {
-  const MCSection *Section = getContext().getObjectFileInfo()->getBSSSection();
-  AssignSection(Symbol, Section);
+  // Common symbols do not belong to any actual section.
+  AssignSection(Symbol, NULL);
 
   OS << "\t.lcomm\t" << *Symbol << ',' << Size;
   if (ByteAlign > 1) {