6 files changed, 67 insertions, 3 deletions
diff --git a/lib/CodeGen/AsmPrinter/DIE.cpp b/lib/CodeGen/AsmPrinter/DIE.cpp
index f9bf8b98a6..334c108316 100644
--- a/lib/CodeGen/AsmPrinter/DIE.cpp
+++ b/lib/CodeGen/AsmPrinter/DIE.cpp
@@ -112,6 +112,18 @@ DIE::~DIE() {
     delete Children[i];
 }
 
+/// Climb up the parent chain to get the compile unit DIE to which this DIE
+/// belongs.
+const DIE *DIE::getCompileUnit() const {
+  const DIE *p = this;
+  while (p) {
+    if (p->getTag() == dwarf::DW_TAG_compile_unit)
+      return p;
+    p = p->getParent();
+  }
+  llvm_unreachable("We should not have orphaned DIEs.");
+}
+
 DIEValue *DIE::findAttribute(uint16_t Attribute) {
   const SmallVectorImpl<DIEValue *> &Values = getValues();
   const DIEAbbrev &Abbrevs = getAbbrev();
diff --git a/lib/CodeGen/AsmPrinter/DIE.h b/lib/CodeGen/AsmPrinter/DIE.h
index 6d4f305c84..96a01327f7 100644
--- a/lib/CodeGen/AsmPrinter/DIE.h
+++ b/lib/CodeGen/AsmPrinter/DIE.h
@@ -146,6 +146,9 @@ namespace llvm {
     const std::vector<DIE *> &getChildren() const { return Children; }
     const SmallVectorImpl<DIEValue*> &getValues() const { return Values; }
     DIE *getParent() const { return Parent; }
+    /// Climb up the parent chain to get the compile unit DIE this DIE belongs
+    /// to.
+    const DIE *getCompileUnit() const;
     void setOffset(unsigned O) { Offset = O; }
     void setSize(unsigned S) { Size = S; }
 
diff --git a/lib/CodeGen/AsmPrinter/DwarfCompileUnit.cpp b/lib/CodeGen/AsmPrinter/DwarfCompileUnit.cpp
index db8558cfec..27ba19a896 100644
--- a/lib/CodeGen/AsmPrinter/DwarfCompileUnit.cpp
+++ b/lib/CodeGen/AsmPrinter/DwarfCompileUnit.cpp
@@ -33,7 +33,8 @@ using namespace llvm;
 /// CompileUnit - Compile unit constructor.
 CompileUnit::CompileUnit(unsigned UID, DIE *D, const MDNode *N, AsmPrinter *A,
                          DwarfDebug *DW, DwarfUnits *DWU)
-    : UniqueID(UID), Node(N), CUDie(D), Asm(A), DD(DW), DU(DWU), IndexTyDie(0) {
+    : UniqueID(UID), Node(N), CUDie(D), Asm(A), DD(DW), DU(DWU), IndexTyDie(0),
+      DebugInfoOffset(0) {
   DIEIntegerOne = new (DIEValueAllocator) DIEInteger(1);
   insertDIE(N, D);
 }
diff --git a/lib/CodeGen/AsmPrinter/DwarfCompileUnit.h b/lib/CodeGen/AsmPrinter/DwarfCompileUnit.h
index 1759ac4bda..4a59ec544d 100644
--- a/lib/CodeGen/AsmPrinter/DwarfCompileUnit.h
+++ b/lib/CodeGen/AsmPrinter/DwarfCompileUnit.h
@@ -120,6 +120,9 @@ public:
     return AccelTypes;
   }
 
+  unsigned getDebugInfoOffset() const { return DebugInfoOffset; }
+  void setDebugInfoOffset(unsigned DbgInfoOff) { DebugInfoOffset = DbgInfoOff; }
+
   /// hasContent - Return true if this compile unit has something to write out.
   ///
   bool hasContent() const { return !CUDie->getChildren().empty(); }
@@ -347,6 +350,9 @@ private:
   /// getOrCreateStaticMemberDIE - Create new static data member DIE.
   DIE *getOrCreateStaticMemberDIE(DIDerivedType DT);
 
+  /// Offset of the CUDie from beginning of debug info section.
+  unsigned DebugInfoOffset;
+
   /// getLowerBoundDefault - Return the default lower bound for an array. If the
   /// DWARF version doesn't handle the language, return -1.
   int64_t getDefaultLowerBound() const;
diff --git a/lib/CodeGen/AsmPrinter/DwarfDebug.cpp b/lib/CodeGen/AsmPrinter/DwarfDebug.cpp
index f491d01876..722dd32d7e 100644
--- a/lib/CodeGen/AsmPrinter/DwarfDebug.cpp
+++ b/lib/CodeGen/AsmPrinter/DwarfDebug.cpp
@@ -821,6 +821,7 @@ CompileUnit *DwarfDebug::constructCompileUnit(const MDNode *N) {
   InfoHolder.addUnit(NewCU);
 
   CUMap.insert(std::make_pair(N, NewCU));
+  CUDieMap.insert(std::make_pair(Die, NewCU));
   return NewCU;
 }
 
@@ -1915,7 +1916,8 @@ void DwarfDebug::recordSourceLine(unsigned Line, unsigned Col, const MDNode *S,
 // Emit Methods
 //===----------------------------------------------------------------------===//
 
-// Compute the size and offset of a DIE.
+// Compute the size and offset of a DIE. The offset is relative to start of the
+// CU. It returns the offset after laying out the DIE.
 unsigned
 DwarfUnits::computeSizeAndOffset(DIE *Die, unsigned Offset) {
   // Get the children.
@@ -1960,16 +1962,26 @@ DwarfUnits::computeSizeAndOffset(DIE *Die, unsigned Offset) {
 
 // Compute the size and offset for each DIE.
 void DwarfUnits::computeSizeAndOffsets() {
+  // Offset from the first CU in the debug info section is 0 initially.
+  unsigned SecOffset = 0;
+
   // Iterate over each compile unit and set the size and offsets for each
   // DIE within each compile unit. All offsets are CU relative.
   for (SmallVectorImpl<CompileUnit *>::iterator I = CUs.begin(),
          E = CUs.end(); I != E; ++I) {
+    (*I)->setDebugInfoOffset(SecOffset);
+
+    // CU-relative offset is reset to 0 here.
     unsigned Offset =
       sizeof(int32_t) + // Length of Compilation Unit Info
       sizeof(int16_t) + // DWARF version number
       sizeof(int32_t) + // Offset Into Abbrev. Section
       sizeof(int8_t);   // Pointer Size (in bytes)
-    computeSizeAndOffset((*I)->getCUDie(), Offset);
+
+    // EndOffset here is CU-relative, after laying out
+    // all of the CU DIE.
+    unsigned EndOffset = computeSizeAndOffset((*I)->getCUDie(), Offset);
+    SecOffset += EndOffset;
   }
 }
 
@@ -2049,6 +2061,33 @@ void DwarfDebug::emitDIE(DIE *Die, std::vector<DIEAbbrev *> *Abbrevs) {
       Asm->OutStreamer.AddComment(dwarf::AttributeString(Attr));
 
     switch (Attr) {
+    case dwarf::DW_AT_abstract_origin:
+    case dwarf::DW_AT_type:
+    case dwarf::DW_AT_friend:
+    case dwarf::DW_AT_specification:
+    case dwarf::DW_AT_import:
+    case dwarf::DW_AT_containing_type: {
+      DIEEntry *E = cast<DIEEntry>(Values[i]);
+      DIE *Origin = E->getEntry();
+      unsigned Addr = Origin->getOffset();
+      if (Form == dwarf::DW_FORM_ref_addr) {
+        assert(!useSplitDwarf() && "TODO: dwo files can't have relocations.");
+        // For DW_FORM_ref_addr, output the offset from beginning of debug info
+        // section. Origin->getOffset() returns the offset from start of the
+        // compile unit.
+        CompileUnit *CU = CUDieMap.lookup(Origin->getCompileUnit());
+        assert(CU && "CUDie should belong to a CU.");
+        Addr += CU->getDebugInfoOffset();
+        if (Asm->MAI->doesDwarfUseRelocationsAcrossSections())
+          Asm->EmitLabelPlusOffset(DwarfInfoSectionSym, Addr,
+                                   DIEEntry::getRefAddrSize(Asm));
+        else
+          Asm->OutStreamer.EmitIntValue(Addr, DIEEntry::getRefAddrSize(Asm));
+      } else {
+        Asm->EmitInt32(Addr);
+      }
+      break;
+    }
     case dwarf::DW_AT_ranges: {
       // DW_AT_range Value encodes offset in debug_range section.
       DIEInteger *V = cast<DIEInteger>(Values[i]);
diff --git a/lib/CodeGen/AsmPrinter/DwarfDebug.h b/lib/CodeGen/AsmPrinter/DwarfDebug.h
index 83ea0cc967..d3ce12c67a 100644
--- a/lib/CodeGen/AsmPrinter/DwarfDebug.h
+++ b/lib/CodeGen/AsmPrinter/DwarfDebug.h
@@ -329,6 +329,9 @@ class DwarfDebug {
   // Maps subprogram MDNode with its corresponding CompileUnit.
   DenseMap <const MDNode *, CompileUnit *> SPMap;
 
+  // Maps a CU DIE with its corresponding CompileUnit.
+  DenseMap <const DIE *, CompileUnit *> CUDieMap;
+
   // Used to uniquely define abbreviations.
   FoldingSet<DIEAbbrev> AbbreviationsSet;