diff --git a/docs/SourceLevelDebugging.rst b/docs/SourceLevelDebugging.rst
index a4fbd72167f..869d3a38310 100644
--- a/docs/SourceLevelDebugging.rst
+++ b/docs/SourceLevelDebugging.rst
@@ -570,6 +570,7 @@ Local variables
     metadata, ;; Reference to the type descriptor
     i32,      ;; flags
     metadata  ;; (optional) Reference to inline location
+    metadata  ;; (optional) Reference to a complex expression (see below)
   }
 
 These descriptors are used to define variables local to a sub program.  The
diff --git a/include/llvm/IR/DebugInfo.h b/include/llvm/IR/DebugInfo.h
index 65e0a0625f7..f225075bd9a 100644
--- a/include/llvm/IR/DebugInfo.h
+++ b/include/llvm/IR/DebugInfo.h
@@ -690,12 +690,17 @@ public:
   /// HasComplexAddr - Return true if the variable has a complex address.
   bool hasComplexAddress() const { return getNumAddrElements() > 0; }
 
-  unsigned getNumAddrElements() const;
-
-  uint64_t getAddrElement(unsigned Idx) const {
-    return getUInt64Field(Idx + 8);
+  /// \brief Return the size of this variable's complex address or
+  /// zero if there is none.
+  unsigned getNumAddrElements() const {
+    if (DbgNode->getNumOperands() < 9)
+      return 0;
+    return getDescriptorField(8)->getNumOperands();
   }
 
+  /// \brief return the Idx'th complex address element.
+  uint64_t getAddrElement(unsigned Idx) const;
+
   /// isBlockByrefVariable - Return true if the variable was declared as
   /// a "__block" variable (Apple Blocks).
   bool isBlockByrefVariable(const DITypeIdentifierMap &Map) const {
diff --git a/lib/IR/DIBuilder.cpp b/lib/IR/DIBuilder.cpp
index 11350401c7b..218787c9933 100644
--- a/lib/IR/DIBuilder.cpp
+++ b/lib/IR/DIBuilder.cpp
@@ -1075,18 +1075,19 @@ DIVariable DIBuilder::createComplexVariable(unsigned Tag, DIDescriptor Scope,
                                             DITypeRef Ty,
                                             ArrayRef<Value *> Addr,
                                             unsigned ArgNo) {
-  SmallVector<Value *, 15> Elts;
-  Elts.push_back(GetTagConstant(VMContext, Tag));
-  Elts.push_back(getNonCompileUnitScope(Scope)),
-  Elts.push_back(MDString::get(VMContext, Name));
-  Elts.push_back(F);
-  Elts.push_back(ConstantInt::get(Type::getInt32Ty(VMContext),
-                                  (LineNo | (ArgNo << 24))));
-  Elts.push_back(Ty);
-  Elts.push_back(Constant::getNullValue(Type::getInt32Ty(VMContext)));
-  Elts.push_back(Constant::getNullValue(Type::getInt32Ty(VMContext)));
-  Elts.append(Addr.begin(), Addr.end());
-
+  assert(Addr.size() > 0 && "complex address is empty");
+  Value *Elts[] = {
+    GetTagConstant(VMContext, Tag),
+    getNonCompileUnitScope(Scope),
+    MDString::get(VMContext, Name),
+    F,
+    ConstantInt::get(Type::getInt32Ty(VMContext),
+                     (LineNo | (ArgNo << 24))),
+    Ty,
+    Constant::getNullValue(Type::getInt32Ty(VMContext)),
+    Constant::getNullValue(Type::getInt32Ty(VMContext)),
+    MDNode::get(VMContext, Addr)
+  };
   return DIVariable(MDNode::get(VMContext, Elts));
 }
 
diff --git a/lib/IR/DebugInfo.cpp b/lib/IR/DebugInfo.cpp
index db9e56defa1..9f35efa1ad9 100644
--- a/lib/IR/DebugInfo.cpp
+++ b/lib/IR/DebugInfo.cpp
@@ -138,8 +138,14 @@ void DIDescriptor::replaceFunctionField(unsigned Elt, Function *F) {
   }
 }
 
-unsigned DIVariable::getNumAddrElements() const {
-  return DbgNode->getNumOperands() - 8;
+uint64_t DIVariable::getAddrElement(unsigned Idx) const {
+  DIDescriptor ComplexExpr = getDescriptorField(8);
+  if (Idx < ComplexExpr->getNumOperands())
+    if (auto *CI = dyn_cast_or_null<ConstantInt>(ComplexExpr->getOperand(Idx)))
+      return CI->getZExtValue();
+
+  assert(false && "non-existing complex address element requested");
+  return 0;
 }
 
 /// getInlinedAt - If this variable is inlined then return inline location.
@@ -566,7 +572,13 @@ bool DIVariable::Verify() const {
   // Make sure that type @ field 5 is a DITypeRef.
   if (!fieldIsTypeRef(DbgNode, 5))
     return false;
-  return DbgNode->getNumOperands() >= 8;
+
+  // Variable without a complex expression.
+  if (DbgNode->getNumOperands() == 8)
+    return true;
+
+  // Make sure the complex expression is an MDNode.
+  return (DbgNode->getNumOperands() == 9 && fieldIsMDNode(DbgNode, 8));
 }
 
 /// Verify - Verify that a location descriptor is well formed.
diff --git a/test/CodeGen/ARM/debug-info-blocks.ll b/test/CodeGen/ARM/debug-info-blocks.ll
index 6cbe4b4727c..5ad5e59b880 100644
--- a/test/CodeGen/ARM/debug-info-blocks.ll
+++ b/test/CodeGen/ARM/debug-info-blocks.ll
@@ -231,10 +231,10 @@ define hidden void @foobar_func_block_invoke_0(i8* %.block_descriptor, %0* %load
 !133 = metadata !{i32 609, i32 175, metadata !23, null}
 !134 = metadata !{i32 786689, metadata !23, metadata !"data", metadata !24, i32 67109473, metadata !108, i32 0, null} ; [ DW_TAG_arg_variable ]
 !135 = metadata !{i32 609, i32 190, metadata !23, null}
-!136 = metadata !{i32 786688, metadata !23, metadata !"mydata", metadata !24, i32 604, metadata !50, i32 0, null, i64 1, i64 20, i64 2, i64 1, i64 4, i64 2, i64 1, i64 24} ; [ DW_TAG_auto_variable ]
+!136 = metadata !{i32 786688, metadata !23, metadata !"mydata", metadata !24, i32 604, metadata !50, i32 0, null, metadata !163} ; [ DW_TAG_auto_variable ]
 !137 = metadata !{i32 604, i32 49, metadata !23, null}
-!138 = metadata !{i32 786688, metadata !23, metadata !"self", metadata !40, i32 604, metadata !90, i32 0, null, i64 1, i64 24} ; [ DW_TAG_auto_variable ]
-!139 = metadata !{i32 786688, metadata !23, metadata !"semi", metadata !24, i32 607, metadata !125, i32 0, null, i64 1, i64 28} ; [ DW_TAG_auto_variable ]
+!138 = metadata !{i32 786688, metadata !23, metadata !"self", metadata !40, i32 604, metadata !90, i32 0, null, metadata !164} ; [ DW_TAG_auto_variable ]
+!139 = metadata !{i32 786688, metadata !23, metadata !"semi", metadata !24, i32 607, metadata !125, i32 0, null, metadata !165} ; [ DW_TAG_auto_variable ]
 !140 = metadata !{i32 607, i32 30, metadata !23, null}
 !141 = metadata !{i32 610, i32 17, metadata !142, null}
 !142 = metadata !{i32 786443, metadata !152, metadata !23, i32 609, i32 200, i32 94} ; [ DW_TAG_lexical_block ]
@@ -258,3 +258,6 @@ define hidden void @foobar_func_block_invoke_0(i8* %.block_descriptor, %0* %load
 !160 = metadata !{metadata !"header.h", metadata !"/Volumes/Sandbox/llvm"}
 !161 = metadata !{metadata !"header2.h", metadata !"/Volumes/Sandbox/llvm"}
 !162 = metadata !{i32 1, metadata !"Debug Info Version", i32 1}
+!163 = metadata !{i64 1, i64 20, i64 2, i64 1, i64 4, i64 2, i64 1, i64 24}
+!164 = metadata !{i64 1, i64 24}
+!165 = metadata !{i64 1, i64 28}
diff --git a/test/DebugInfo/X86/block-capture.ll b/test/DebugInfo/X86/block-capture.ll
index 2b4b3e54a85..e842afe9446 100644
--- a/test/DebugInfo/X86/block-capture.ll
+++ b/test/DebugInfo/X86/block-capture.ll
@@ -118,7 +118,7 @@ declare i32 @__objc_personality_v0(...)
 !50 = metadata !{i32 786445, metadata !63, metadata !6, metadata !"block", i32 7, i64 64, i64 64, i64 256, i32 0, metadata !9} ; [ DW_TAG_member ]
 !51 = metadata !{i32 7, i32 18, metadata !28, null}
 !52 = metadata !{i32 7, i32 19, metadata !28, null}
-!53 = metadata !{i32 786688, metadata !28, metadata !"block", metadata !6, i32 5, metadata !9, i32 0, i32 0, i64 1, i64 32} ; [ DW_TAG_auto_variable ]
+!53 = metadata !{i32 786688, metadata !28, metadata !"block", metadata !6, i32 5, metadata !9, i32 0, i32 0, metadata !65} ; [ DW_TAG_auto_variable ]
 !54 = metadata !{i32 5, i32 27, metadata !28, null}
 !55 = metadata !{i32 8, i32 22, metadata !56, null}
 !56 = metadata !{i32 786443, metadata !6, metadata !57, i32 7, i32 26, i32 2} ; [ DW_TAG_lexical_block ]
@@ -130,3 +130,4 @@ declare i32 @__objc_personality_v0(...)
 !62 = metadata !{i32 9, i32 20, metadata !56, null}
 !63 = metadata !{metadata !"foo.m", metadata !"/Users/echristo"}
 !64 = metadata !{i32 1, metadata !"Debug Info Version", i32 1}
+!65 = metadata !{i64 1, i64 32}
diff --git a/test/DebugInfo/X86/dbg_value_direct.ll b/test/DebugInfo/X86/dbg_value_direct.ll
index 28b7dc6b9b2..db947ac9479 100644
--- a/test/DebugInfo/X86/dbg_value_direct.ll
+++ b/test/DebugInfo/X86/dbg_value_direct.ll
@@ -170,8 +170,9 @@ attributes #2 = { "less-precise-fpmad"="false" "no-frame-pointer-elim"="true" "n
 !20 = metadata !{i32 786468}
 !21 = metadata !{i32 786468, null, null, metadata !"int", i32 0, i64 32, i64 32, i64 0, i32 0, i32 5} ; [ DW_TAG_base_type ] [int] [line 0, size 32, align 32, offset 0, enc DW_ATE_signed]
 !22 = metadata !{i32 2, metadata !"Dwarf Version", i32 3}
-!23 = metadata !{i32 786689, metadata !4, metadata !"", metadata !5, i32 16777222, metadata !21, i32 0, i32 0, i64 2} ; [ DW_TAG_arg_variable ] [line 6]
+!23 = metadata !{i32 786689, metadata !4, metadata !"", metadata !5, i32 16777222, metadata !21, i32 0, i32 0, metadata !28} ; [ DW_TAG_arg_variable ] [line 6]
 !24 = metadata !{i32 786688, metadata !4, metadata !"a", metadata !5, i32 7, metadata !8, i32 8192, i32 0} ; [ DW_TAG_auto_variable ] [a] [line 7]
 !25 = metadata !{i32 7, i32 0, metadata !4, null}
 !26 = metadata !{i32 8, i32 0, metadata !4, null} ; [ DW_TAG_imported_declaration ]
 !27 = metadata !{i32 1, metadata !"Debug Info Version", i32 1}
+!28 = metadata !{i64 2}
diff --git a/test/DebugInfo/X86/debug-info-block-captured-self.ll b/test/DebugInfo/X86/debug-info-block-captured-self.ll
index d753cc0f41e..95eda60c5cc 100644
--- a/test/DebugInfo/X86/debug-info-block-captured-self.ll
+++ b/test/DebugInfo/X86/debug-info-block-captured-self.ll
@@ -101,10 +101,12 @@ define internal void @"__24-[Main initWithContext:]_block_invoke_2"(i8* %.block_
 !41 = metadata !{i32 786447, null, null, metadata !"", i32 0, i64 64, i64 64, i64 0, i32 0, null} ; [ DW_TAG_pointer_type ] [line 0, size 64, align 64, offset 0] [from ]
 !42 = metadata !{i32 786478, metadata !1, metadata !1, metadata !"__24-[Main initWithContext:]_block_invoke_2", metadata !"__24-[Main initWithContext:]_block_invoke_2", metadata !"", i32 35, metadata !39, i1 true, i1 true, i32 0, i32 0, null, i32 256, i1 false, void (i8*, i8*)* @"__24-[Main initWithContext:]_block_invoke_2", null, null, metadata !15, i32 35} ; [ DW_TAG_subprogram ] [line 35] [local] [def] [__24-[Main initWithContext:]_block_invoke_2]
 !84 = metadata !{i32 33, i32 0, metadata !38, null}
-!86 = metadata !{i32 786688, metadata !38, metadata !"self", metadata !1, i32 41, metadata !34, i32 0, i32 0, i64 1, i64 32} ; [ DW_TAG_auto_variable ] [self] [line 41]
+!86 = metadata !{i32 786688, metadata !38, metadata !"self", metadata !1, i32 41, metadata !34, i32 0, i32 0, metadata !110} ; [ DW_TAG_auto_variable ] [self] [line 41]
 !87 = metadata !{i32 41, i32 0, metadata !38, null}
 !103 = metadata !{i32 35, i32 0, metadata !42, null}
-!105 = metadata !{i32 786688, metadata !42, metadata !"self", metadata !1, i32 40, metadata !34, i32 0, i32 0, i64 1, i64 32} ; [ DW_TAG_auto_variable ] [self] [line 40]
+!105 = metadata !{i32 786688, metadata !42, metadata !"self", metadata !1, i32 40, metadata !34, i32 0, i32 0, metadata !109} ; [ DW_TAG_auto_variable ] [self] [line 40]
 !106 = metadata !{i32 40, i32 0, metadata !42, null}
 !107 = metadata !{metadata !"llvm/tools/clang/test/CodeGenObjC/debug-info-block-captured-self.m", metadata !""}
 !108 = metadata !{i32 1, metadata !"Debug Info Version", i32 1}
+!109 = metadata !{i64 1, i64 32}
+!110 = metadata !{i64 1, i64 32}
diff --git a/test/DebugInfo/X86/debug-info-blocks.ll b/test/DebugInfo/X86/debug-info-blocks.ll
index db1143cfa3f..8a1a125ff80 100644
--- a/test/DebugInfo/X86/debug-info-blocks.ll
+++ b/test/DebugInfo/X86/debug-info-blocks.ll
@@ -359,7 +359,7 @@ attributes #3 = { nounwind }
 !86 = metadata !{i32 786451, metadata !1, null, metadata !"__block_descriptor_withcopydispose", i32 49, i64 0, i64 0, i32 0, i32 4, null, null, i32 0, null, null, null} ; [ DW_TAG_structure_type ] [__block_descriptor_withcopydispose] [line 49, size 0, align 0, offset 0] [decl] [from ]
 !87 = metadata !{i32 786445, metadata !5, metadata !6, metadata !"self", i32 49, i64 64, i64 64, i64 256, i32 0, metadata !61} ; [ DW_TAG_member ] [self] [line 49, size 64, align 64, offset 256] [from ]
 !88 = metadata !{i32 49, i32 0, metadata !27, null}
-!89 = metadata !{i32 786688, metadata !27, metadata !"self", metadata !32, i32 52, metadata !23, i32 0, i32 0, i64 2, i64 1, i64 32} ; [ DW_TAG_auto_variable ] [self] [line 52]
+!89 = metadata !{i32 786688, metadata !27, metadata !"self", metadata !32, i32 52, metadata !23, i32 0, i32 0, metadata !111} ; [ DW_TAG_auto_variable ] [self] [line 52]
 !90 = metadata !{i32 52, i32 0, metadata !27, null}
 !91 = metadata !{i32 786688, metadata !92, metadata !"d", metadata !6, i32 50, metadata !93, i32 0, i32 0} ; [ DW_TAG_auto_variable ] [d] [line 50]
 !92 = metadata !{i32 786443, metadata !5, metadata !27, i32 49, i32 0, i32 2} ; [ DW_TAG_lexical_block ] [llvm/tools/clang/test/CodeGenObjC/debug-info-blocks.m]
@@ -381,3 +381,4 @@ attributes #3 = { nounwind }
 !108 = metadata !{i32 61, i32 0, metadata !36, null}
 !109 = metadata !{i32 62, i32 0, metadata !36, null}
 !110 = metadata !{i32 1, metadata !"Debug Info Version", i32 1}
+!111 = metadata !{i64 2, i64 1, i64 32}
diff --git a/test/DebugInfo/X86/debug-loc-asan.ll b/test/DebugInfo/X86/debug-loc-asan.ll
index 746b1dcaa3e..b1980ecda2d 100644
--- a/test/DebugInfo/X86/debug-loc-asan.ll
+++ b/test/DebugInfo/X86/debug-loc-asan.ll
@@ -181,6 +181,6 @@ attributes #1 = { nounwind readnone }
 !9 = metadata !{i32 2, metadata !"Dwarf Version", i32 4}
 !10 = metadata !{i32 2, metadata !"Debug Info Version", i32 1}
 !11 = metadata !{metadata !"clang version 3.5.0 (209308)"}
-!12 = metadata !{i32 786689, metadata !4, metadata !"y", metadata !5, i32 16777217, metadata !8, i32 0, i32 0, i64 2} ; [ DW_TAG_arg_variable ] [y] [line 1]
+!12 = metadata !{i32 786689, metadata !4, metadata !"y", metadata !5, i32 16777217, metadata !8, i32 0, i32 0, metadata !14} ; [ DW_TAG_arg_variable ] [y] [line 1]
 !13 = metadata !{i32 2, i32 0, metadata !4, null}
-
+!14 = metadata !{i64 2}
diff --git a/test/DebugInfo/X86/op_deref.ll b/test/DebugInfo/X86/op_deref.ll
index 59382d19f1f..31003eee2a8 100644
--- a/test/DebugInfo/X86/op_deref.ll
+++ b/test/DebugInfo/X86/op_deref.ll
@@ -89,7 +89,7 @@ declare void @llvm.stackrestore(i8*) nounwind
 !11 = metadata !{i32 1, i32 26, metadata !5, null}
 !12 = metadata !{i32 3, i32 13, metadata !13, null}
 !13 = metadata !{i32 786443, metadata !28, metadata !5, i32 2, i32 1, i32 0} ; [ DW_TAG_lexical_block ]
-!14 = metadata !{i32 786688, metadata !13, metadata !"vla", metadata !6, i32 3, metadata !15, i32 8192, i32 0, i64 2} ; [ DW_TAG_auto_variable ]
+!14 = metadata !{i32 786688, metadata !13, metadata !"vla", metadata !6, i32 3, metadata !15, i32 8192, i32 0, metadata !30} ; [ DW_TAG_auto_variable ]
 !15 = metadata !{i32 786433, null, null, metadata !"", i32 0, i64 0, i64 32, i32 0, i32 0, metadata !9, metadata !16, i32 0, null, null, null} ; [ DW_TAG_array_type ] [line 0, size 0, align 32, offset 0] [from int]
 !16 = metadata !{metadata !17}
 !17 = metadata !{i32 786465, i64 0, i64 -1}        ; [ DW_TAG_subrange_type ]
@@ -105,3 +105,4 @@ declare void @llvm.stackrestore(i8*) nounwind
 !27 = metadata !{i32 8, i32 1, metadata !13, null}
 !28 = metadata !{metadata !"bar.c", metadata !"/Users/echristo/tmp"}
 !29 = metadata !{i32 1, metadata !"Debug Info Version", i32 1}
+!30 = metadata !{i64 2}
diff --git a/test/Instrumentation/AddressSanitizer/debug_info.ll b/test/Instrumentation/AddressSanitizer/debug_info.ll
index a4501d2ed29..336b98b289c 100644
--- a/test/Instrumentation/AddressSanitizer/debug_info.ll
+++ b/test/Instrumentation/AddressSanitizer/debug_info.ll
@@ -47,8 +47,9 @@ declare void @llvm.dbg.declare(metadata, metadata) nounwind readnone
 
 ; Verify that debug descriptors for argument and local variable will be replaced
 ; with descriptors that end with OpDeref (encoded as 2).
-;   CHECK: ![[ARG_ID]] = metadata {{.*}} i64 2} ; [ DW_TAG_arg_variable ] [p] [line 1]
-;   CHECK: ![[VAR_ID]] = metadata {{.*}} i64 2} ; [ DW_TAG_auto_variable ] [r] [line 2]
+;   CHECK: ![[ARG_ID]] = {{.*}}metadata ![[OPDEREF:[0-9]+]]} ; [ DW_TAG_arg_variable ] [p] [line 1]
+;   CHECK: ![[OPDEREF]] = metadata !{i64 2}
+;   CHECK: ![[VAR_ID]] = {{.*}}metadata ![[OPDEREF]]} ; [ DW_TAG_auto_variable ] [r] [line 2]
 ; Verify that there are no more variable descriptors.
 ;   CHECK-NOT: DW_TAG_arg_variable
 ;   CHECK-NOT: DW_TAG_auto_variable