diff --git a/lib/CodeGen/AsmPrinter/DwarfAccelTable.h b/lib/CodeGen/AsmPrinter/DwarfAccelTable.h
index 2ae2402a7a5..e7867db3c66 100644
--- a/lib/CodeGen/AsmPrinter/DwarfAccelTable.h
+++ b/lib/CodeGen/AsmPrinter/DwarfAccelTable.h
@@ -18,6 +18,7 @@
 #include "llvm/ADT/ArrayRef.h"
 #include "llvm/ADT/StringMap.h"
 #include "llvm/MC/MCSymbol.h"
+#include "llvm/Support/Compiler.h"
 #include "llvm/Support/DataTypes.h"
 #include "llvm/Support/Debug.h"
 #include "llvm/Support/Dwarf.h"
@@ -125,7 +126,8 @@ public:
     uint16_t type; // enum AtomType
     uint16_t form; // DWARF DW_FORM_ defines
 
-    Atom(uint16_t type, uint16_t form) : type(type), form(form) {}
+    LLVM_CONSTEXPR Atom(uint16_t type, uint16_t form)
+        : type(type), form(form) {}
 #ifndef NDEBUG
     void print(raw_ostream &O) {
       O << "Type: " << dwarf::AtomTypeString(type) << "\n"
diff --git a/lib/CodeGen/AsmPrinter/DwarfDebug.cpp b/lib/CodeGen/AsmPrinter/DwarfDebug.cpp
index 5490721bc05..531c44cde4c 100644
--- a/lib/CodeGen/AsmPrinter/DwarfDebug.cpp
+++ b/lib/CodeGen/AsmPrinter/DwarfDebug.cpp
@@ -164,6 +164,11 @@ DIType DbgVariable::getType() const {
   return Ty;
 }
 
+static LLVM_CONSTEXPR DwarfAccelTable::Atom TypeAtoms[] = {
+    DwarfAccelTable::Atom(dwarf::DW_ATOM_die_offset, dwarf::DW_FORM_data4),
+    DwarfAccelTable::Atom(dwarf::DW_ATOM_die_tag, dwarf::DW_FORM_data2),
+    DwarfAccelTable::Atom(dwarf::DW_ATOM_type_flags, dwarf::DW_FORM_data1)};
+
 DwarfDebug::DwarfDebug(AsmPrinter *A, Module *M)
     : Asm(A), MMI(Asm->MMI), FirstCU(0), PrevLabel(NULL), GlobalRangeCount(0),
       InfoHolder(A, "info_string", DIEValueAllocator),
@@ -174,7 +179,8 @@ DwarfDebug::DwarfDebug(AsmPrinter *A, Module *M)
       AccelObjC(DwarfAccelTable::Atom(dwarf::DW_ATOM_die_offset,
                                       dwarf::DW_FORM_data4)),
       AccelNamespace(DwarfAccelTable::Atom(dwarf::DW_ATOM_die_offset,
-                                           dwarf::DW_FORM_data4)) {
+                                           dwarf::DW_FORM_data4)),
+      AccelTypes(TypeAtoms) {
 
   DwarfInfoSectionSym = DwarfAbbrevSectionSym = DwarfStrSectionSym = 0;
   DwarfDebugRangeSectionSym = DwarfDebugLocSectionSym = DwarfLineSectionSym = 0;
@@ -1899,27 +1905,15 @@ void DwarfDebug::emitAccelNamespaces() {
 
 // Emit type dies into a hashed accelerator table.
 void DwarfDebug::emitAccelTypes() {
-  DwarfAccelTable::Atom Atoms[] = {
-      DwarfAccelTable::Atom(dwarf::DW_ATOM_die_offset, dwarf::DW_FORM_data4),
-      DwarfAccelTable::Atom(dwarf::DW_ATOM_die_tag, dwarf::DW_FORM_data2),
-      DwarfAccelTable::Atom(dwarf::DW_ATOM_type_flags, dwarf::DW_FORM_data1)};
-  DwarfAccelTable AT(Atoms);
-  for (const auto &TheU : getUnits()) {
-    for (const auto &GI : TheU->getAccelTypes()) {
-      StringRef Name = GI.getKey();
-      for (const auto &DI : GI.second)
-        AT.AddName(Name, DI.first, DI.second);
-    }
-  }
 
-  AT.FinalizeTable(Asm, "types");
+  AccelTypes.FinalizeTable(Asm, "types");
   Asm->OutStreamer.SwitchSection(
       Asm->getObjFileLowering().getDwarfAccelTypesSection());
   MCSymbol *SectionBegin = Asm->GetTempSymbol("types_begin");
   Asm->OutStreamer.EmitLabel(SectionBegin);
 
   // Emit the full data.
-  AT.Emit(Asm, SectionBegin, &InfoHolder);
+  AccelTypes.Emit(Asm, SectionBegin, &InfoHolder);
 }
 
 // Public name handling.
@@ -2567,3 +2561,10 @@ void DwarfDebug::addAccelNamespace(StringRef Name, const DIE *Die) {
   InfoHolder.getStringPoolEntry(Name);
   AccelNamespace.AddName(Name, Die);
 }
+
+void DwarfDebug::addAccelType(StringRef Name, const DIE *Die, char Flags) {
+  if (!useDwarfAccelTables())
+    return;
+  InfoHolder.getStringPoolEntry(Name);
+  AccelTypes.AddName(Name, Die, Flags);
+}
diff --git a/lib/CodeGen/AsmPrinter/DwarfDebug.h b/lib/CodeGen/AsmPrinter/DwarfDebug.h
index f3367f4cebe..02887b10fd0 100644
--- a/lib/CodeGen/AsmPrinter/DwarfDebug.h
+++ b/lib/CodeGen/AsmPrinter/DwarfDebug.h
@@ -327,6 +327,7 @@ class DwarfDebug : public AsmPrinterHandler {
   DwarfAccelTable AccelNames;
   DwarfAccelTable AccelObjC;
   DwarfAccelTable AccelNamespace;
+  DwarfAccelTable AccelTypes;
 
   MCDwarfDwoLineTable *getDwoLineTable(const DwarfCompileUnit &);
 
@@ -648,6 +649,8 @@ public:
   void addAccelObjC(StringRef Name, const DIE *Die);
 
   void addAccelNamespace(StringRef Name, const DIE *Die);
+
+  void addAccelType(StringRef Name, const DIE *Die, char Flags);
 };
 } // End of namespace llvm
 
diff --git a/lib/CodeGen/AsmPrinter/DwarfUnit.cpp b/lib/CodeGen/AsmPrinter/DwarfUnit.cpp
index 9b5923441cd..333829e8a79 100644
--- a/lib/CodeGen/AsmPrinter/DwarfUnit.cpp
+++ b/lib/CodeGen/AsmPrinter/DwarfUnit.cpp
@@ -1035,7 +1035,7 @@ void DwarfUnit::updateAcceleratorTables(DIScope Context, DIType Ty,
       IsImplementation = (CT.getRunTimeLang() == 0) || CT.isObjcClassComplete();
     }
     unsigned Flags = IsImplementation ? dwarf::DW_FLAG_type_implementation : 0;
-    addAccelType(Ty.getName(), std::make_pair(TyDIE, Flags));
+    DD->addAccelType(Ty.getName(), TyDIE, Flags);
 
     if ((!Context || Context.isCompileUnit() || Context.isFile() ||
          Context.isNameSpace()) &&
@@ -1065,15 +1065,6 @@ void DwarfUnit::addType(DIE *Entity, DIType Ty, dwarf::Attribute Attribute) {
   addDIEEntry(Entity, Attribute, Entry);
 }
 
-void DwarfUnit::addAccelType(StringRef Name,
-                             std::pair<const DIE *, unsigned> Die) {
-  if (!DD->useDwarfAccelTables())
-    return;
-  DU->getStringPoolEntry(Name);
-  std::vector<std::pair<const DIE *, unsigned> > &DIEs = AccelTypes[Name];
-  DIEs.push_back(Die);
-}
-
 /// addGlobalName - Add a new global name to the compile unit.
 void DwarfUnit::addGlobalName(StringRef Name, DIE *Die, DIScope Context) {
   if (getCUNode().getEmissionKind() == DIBuilder::LineTablesOnly)
diff --git a/lib/CodeGen/AsmPrinter/DwarfUnit.h b/lib/CodeGen/AsmPrinter/DwarfUnit.h
index 13fb1b5c9e2..c3c9660d473 100644
--- a/lib/CodeGen/AsmPrinter/DwarfUnit.h
+++ b/lib/CodeGen/AsmPrinter/DwarfUnit.h
@@ -102,9 +102,6 @@ protected:
   /// GlobalTypes - A map of globally visible types for this unit.
   StringMap<const DIE *> GlobalTypes;
 
-  /// AccelTypes - A map of names for the type accelerator table.
-  StringMap<std::vector<std::pair<const DIE *, unsigned> > > AccelTypes;
-
   /// DIEBlocks - A list of all the DIEBlocks in use.
   std::vector<DIEBlock *> DIEBlocks;
   
@@ -222,11 +219,6 @@ public:
   const StringMap<const DIE *> &getGlobalNames() const { return GlobalNames; }
   const StringMap<const DIE *> &getGlobalTypes() const { return GlobalTypes; }
 
-  const StringMap<std::vector<std::pair<const DIE *, unsigned> > > &
-  getAccelTypes() const {
-    return AccelTypes;
-  }
-
   unsigned getDebugInfoOffset() const { return DebugInfoOffset; }
   void setDebugInfoOffset(unsigned DbgInfoOff) { DebugInfoOffset = DbgInfoOff; }
 
@@ -260,9 +252,6 @@ public:
   /// addAccelNamespace - Add a new name to the namespace accelerator table.
   void addAccelNamespace(StringRef Name, const DIE *Die);
 
-  /// addAccelType - Add a new type to the type accelerator table.
-  void addAccelType(StringRef Name, std::pair<const DIE *, unsigned> Die);
-
   /// getDIE - Returns the debug information entry map slot for the
   /// specified debug variable. We delegate the request to DwarfDebug
   /// when the MDNode can be part of the type system, since DIEs for