diff --git a/include/llvm/Analysis/DebugInfo.h b/include/llvm/Analysis/DebugInfo.h
index 8082279..c40cfb2 100644
--- a/include/llvm/Analysis/DebugInfo.h
+++ b/include/llvm/Analysis/DebugInfo.h
@@ -187,10 +187,10 @@
   class DIType : public DIDescriptor {
   public:
     enum {
-      FlagPrivate    = 1 << 0,
-      FlagProtected  = 1 << 1,
-      FlagFwdDecl    = 1 << 2,
-      FlagAppleBlock = 1 << 3,
+      FlagPrivate          = 1 << 0,
+      FlagProtected        = 1 << 1,
+      FlagFwdDecl          = 1 << 2,
+      FlagAppleBlock       = 1 << 3,
       FlagBlockByrefStruct = 1 << 4
     };
 
@@ -409,6 +409,17 @@
     /// Verify - Verify that a variable descriptor is well formed.
     bool Verify() const;
 
+    /// HasComplexAddr - Return true if the variable has a complex address.
+    bool hasComplexAddress() const {
+      return getNumAddrElements() > 0;
+    }
+
+    unsigned getNumAddrElements() const { return DbgNode->getNumElements()-6; }
+
+    uint64_t getAddrElement(unsigned Idx) const {
+      return getUInt64Field(Idx+6);
+    }
+
     /// isBlockByrefVariable - Return true if the variable was declared as
     /// a "__block" variable (Apple Blocks).
     bool isBlockByrefVariable() const {
@@ -463,6 +474,8 @@
     DIFactory(const DIFactory &);     // DO NOT IMPLEMENT
     void operator=(const DIFactory&); // DO NOT IMPLEMENT
   public:
+    enum ComplexAddrKind { OpPlus=1, OpDeref };
+
     explicit DIFactory(Module &m);
 
     /// GetOrCreateArray - Create an descriptor for an array of descriptors.
@@ -540,6 +553,14 @@
                               DICompileUnit CompileUnit, unsigned LineNo,
                               DIType Type);
 
+    /// CreateComplexVariable - Create a new descriptor for the specified
+    /// variable which has a complex address expression for its address.
+    DIVariable CreateComplexVariable(unsigned Tag, DIDescriptor Context,
+                                     const std::string &Name,
+                                     DICompileUnit CompileUnit, unsigned LineNo,
+                                     DIType Type,
+                                     SmallVector<Value *, 9> &addr);
+
     /// CreateLexicalBlock - This creates a descriptor for a lexical block
     /// with the specified parent context.
     DILexicalBlock CreateLexicalBlock(DIDescriptor Context);
diff --git a/lib/Analysis/DebugInfo.cpp b/lib/Analysis/DebugInfo.cpp
index 58bee90..db5a0cb 100644
--- a/lib/Analysis/DebugInfo.cpp
+++ b/lib/Analysis/DebugInfo.cpp
@@ -531,6 +531,8 @@
   errs() << " [" << getLineNumber() << "] ";
   getType().dump();
   errs() << "\n";
+
+  // FIXME: Dump complex addresses
 }
 
 //===----------------------------------------------------------------------===//
@@ -781,6 +783,26 @@
 }
 
 
+/// CreateComplexVariable - Create a new descriptor for the specified variable
+/// which has a complex address expression for its address.
+DIVariable DIFactory::CreateComplexVariable(unsigned Tag, DIDescriptor Context,
+                                            const std::string &Name,
+                                            DICompileUnit CompileUnit,
+                                            unsigned LineNo,
+                                   DIType Type, SmallVector<Value *, 9> &addr) {
+  SmallVector<Value *, 9> Elts;
+  Elts.push_back(GetTagConstant(Tag));
+  Elts.push_back(Context.getNode());
+  Elts.push_back(MDString::get(VMContext, Name));
+  Elts.push_back(CompileUnit.getNode());
+  Elts.push_back(ConstantInt::get(Type::getInt32Ty(VMContext), LineNo));
+  Elts.push_back(Type.getNode());
+  Elts.insert(Elts.end(), addr.begin(), addr.end());
+
+  return DIVariable(MDNode::get(VMContext, &Elts[0], 6+addr.size()));
+}
+
+
 /// CreateBlock - This creates a descriptor for a lexical block with the
 /// specified parent VMContext.
 DILexicalBlock DIFactory::CreateLexicalBlock(DIDescriptor Context) {
diff --git a/lib/CodeGen/AsmPrinter/DwarfDebug.cpp b/lib/CodeGen/AsmPrinter/DwarfDebug.cpp
index f667e31..8a74a8e 100644
--- a/lib/CodeGen/AsmPrinter/DwarfDebug.cpp
+++ b/lib/CodeGen/AsmPrinter/DwarfDebug.cpp
@@ -556,7 +556,7 @@
   unsigned tag = Ty.getTag();
 
   if (tag == dwarf::DW_TAG_pointer_type) {
-    DIDerivedType DTy = DIDerivedType (Ty.getNode());
+    DIDerivedType DTy = DIDerivedType(Ty.getNode());
     subType = DTy.getTypeDerivedFrom();
   }
 
@@ -577,6 +577,56 @@
   return Ty;
 }
 
+/// AddComplexAddress - Start with the address based on the location provided,
+/// and generate the DWARF information necessary to find the actual variable
+/// given the extra address information encoded in the DIVariable, starting from
+/// the starting location.  Add the DWARF information to the die.
+///
+void DwarfDebug::AddComplexAddress(DbgVariable *&DV, DIE *Die,
+                                   unsigned Attribute,
+                                   const MachineLocation &Location) {
+  const DIVariable &VD = DV->getVariable();
+  DIType Ty = VD.getType();
+
+  // Decode the original location, and use that as the start of the byref
+  // variable's location.
+  unsigned Reg = RI->getDwarfRegNum(Location.getReg(), false);
+  DIEBlock *Block = new DIEBlock();
+
+  if (Location.isReg()) {
+    if (Reg < 32) {
+      AddUInt(Block, 0, dwarf::DW_FORM_data1, dwarf::DW_OP_reg0 + Reg);
+    } else {
+      Reg = Reg - dwarf::DW_OP_reg0;
+      AddUInt(Block, 0, dwarf::DW_FORM_data1, dwarf::DW_OP_breg0 + Reg);
+      AddUInt(Block, 0, dwarf::DW_FORM_udata, Reg);
+    }
+  } else {
+    if (Reg < 32)
+      AddUInt(Block, 0, dwarf::DW_FORM_data1, dwarf::DW_OP_breg0 + Reg);
+    else {
+      AddUInt(Block, 0, dwarf::DW_FORM_data1, dwarf::DW_OP_bregx);
+      AddUInt(Block, 0, dwarf::DW_FORM_udata, Reg);
+    }
+
+    AddUInt(Block, 0, dwarf::DW_FORM_sdata, Location.getOffset());
+  }
+
+  for (unsigned i = 0, N = VD.getNumAddrElements(); i < N; ++i) {
+    uint64_t Element = VD.getAddrElement(i);
+
+    if (Element == DIFactory::OpPlus) {
+      AddUInt(Block, 0, dwarf::DW_FORM_data1, dwarf::DW_OP_plus_uconst);
+      AddUInt(Block, 0, dwarf::DW_FORM_udata, VD.getAddrElement(++i));
+    } else if (Element == DIFactory::OpDeref) {
+      AddUInt(Block, 0, dwarf::DW_FORM_data1, dwarf::DW_OP_deref);
+    } else llvm_unreachable("unknown DIFactory Opcode");
+  }
+
+  // Now attach the location information to the DIE.
+  AddBlock(Die, Attribute, 0, Block);
+}
+
 /* Byref variables, in Blocks, are declared by the programmer as "SomeType
    VarName;", but the compiler creates a __Block_byref_x_VarName struct, and
    gives the variable VarName either the struct, or a pointer to the struct, as
@@ -649,7 +699,7 @@
   const char *varName = VD.getName();
 
   if (Tag == dwarf::DW_TAG_pointer_type) {
-    DIDerivedType DTy = DIDerivedType (Ty.getNode());
+    DIDerivedType DTy = DIDerivedType(Ty.getNode());
     TmpTy = DTy.getTypeDerivedFrom();
     isPointer = true;
   }
@@ -790,7 +840,6 @@
   else {
     assert(Ty.isDerivedType() && "Unknown kind of DIType");
     ConstructTypeDIE(DW_Unit, Buffer, DIDerivedType(Ty.getNode()));
-
   }
 
   // Add debug information entry to entity and appropriate context.
@@ -1187,6 +1236,7 @@
   AddSourceLine(VariableDie, &VD);
 
   // Add variable type.
+  // FIXME: isBlockByrefVariable should be reformulated in terms of complex addresses instead.
   if (VD.isBlockByrefVariable())
     AddType(Unit, VariableDie, GetBlockByrefType(VD.getType(), Name));
   else
@@ -1200,7 +1250,10 @@
     Location.set(RI->getFrameRegister(*MF),
                  RI->getFrameIndexOffset(*MF, DV->getFrameIndex()));
 
-    if (VD.isBlockByrefVariable())
+
+    if (VD.hasComplexAddress())
+      AddComplexAddress(DV, VariableDie, dwarf::DW_AT_location, Location);
+    else if (VD.isBlockByrefVariable())
       AddBlockByrefAddress(DV, VariableDie, dwarf::DW_AT_location, Location);
     else
       AddAddress(VariableDie, dwarf::DW_AT_location, Location);
diff --git a/lib/CodeGen/AsmPrinter/DwarfDebug.h b/lib/CodeGen/AsmPrinter/DwarfDebug.h
index f582f9b..8899529 100644
--- a/lib/CodeGen/AsmPrinter/DwarfDebug.h
+++ b/lib/CodeGen/AsmPrinter/DwarfDebug.h
@@ -284,10 +284,20 @@
   void AddAddress(DIE *Die, unsigned Attribute,
                   const MachineLocation &Location);
 
+  /// AddComplexAddress - Start with the address based on the location provided,
+  /// and generate the DWARF information necessary to find the actual variable
+  /// (navigating the extra location information encoded in the type) based on
+  /// the starting location.  Add the DWARF information to the die.
+  ///
+  void AddComplexAddress(DbgVariable *&DV, DIE *Die, unsigned Attribute,
+                         const MachineLocation &Location);
+
+  // FIXME: Should be reformulated in terms of AddComplexAddress.
   /// AddBlockByrefAddress - Start with the address based on the location
   /// provided, and generate the DWARF information necessary to find the
   /// actual Block variable (navigating the Block struct) based on the
-  /// starting location.  Add the DWARF information to the die.
+  /// starting location.  Add the DWARF information to the die.  Obsolete,
+  /// please use AddComplexAddress instead.
   ///
   void AddBlockByrefAddress(DbgVariable *&DV, DIE *Die, unsigned Attribute,
                             const MachineLocation &Location);
@@ -459,8 +469,9 @@
 
   void ConstructSubprogram(MDNode *N);
 
+  // FIXME: This should go away in favor of complex addresses.
   /// Find the type the programmer originally declared the variable to be
-  /// and return that type.
+  /// and return that type.  Obsolete, use GetComplexAddrType instead.
   ///
   DIType GetBlockByrefType(DIType Ty, std::string Name);