Index: include/clang/Driver/Options.td
===================================================================
--- include/clang/Driver/Options.td
+++ include/clang/Driver/Options.td
@@ -1773,6 +1773,9 @@
   Group<m_Group>,
   HelpText<"Generate additional code for specified <version> of debugger ABI (AMDGPU only)">,
   MetaVarName<"<version>">;
+def mnew_addr : Flag<["-"], "mnew-addr">,
+  Group<m_amdgpu_Features_Group>,
+  HelpText<"Use new address space mapping for AMDGPU target">;
 
 def mvsx : Flag<["-"], "mvsx">, Group<m_ppc_Features_Group>;
 def mno_vsx : Flag<["-"], "mno-vsx">, Group<m_ppc_Features_Group>;
Index: lib/Basic/Targets.cpp
===================================================================
--- lib/Basic/Targets.cpp
+++ lib/Basic/Targets.cpp
@@ -1997,16 +1997,6 @@
   return llvm::makeArrayRef(GCCRegNames);
 }
 
-static const unsigned AMDGPUAddrSpaceMap[] = {
-  1,    // opencl_global
-  3,    // opencl_local
-  2,    // opencl_constant
-  4,    // opencl_generic
-  1,    // cuda_device
-  2,    // cuda_constant
-  3     // cuda_shared
-};
-
 // If you edit the description strings, make sure you update
 // getPointerWidthV().
 
@@ -2014,15 +2004,65 @@
   "e-p:32:32-i64:64-v16:16-v24:32-v32:32-v48:64-v96:128"
   "-v192:256-v256:256-v512:512-v1024:1024-v2048:2048-n32:64";
 
-static const char *const DataLayoutStringSI =
+static const char *const DataLayoutStringSIOld =
   "e-p:32:32-p1:64:64-p2:64:64-p3:32:32-p4:64:64-p5:32:32"
   "-i64:64-v16:16-v24:32-v32:32-v48:64-v96:128"
   "-v192:256-v256:256-v512:512-v1024:1024-v2048:2048-n32:64";
 
+static const char *const DataLayoutStringSINew =
+  "e-p:64:64-p1:64:64-p2:64:64-p3:32:32-p4:64:64-p5:32:32"
+  "-i64:64-v16:16-v24:32-v32:32-v48:64-v96:128"
+  "-v192:256-v256:256-v512:512-v1024:1024-v2048:2048-n32:64";
+
 class AMDGPUTargetInfo final : public TargetInfo {
   static const Builtin::Info BuiltinInfo[];
   static const char * const GCCRegNames[];
 
+  struct AddrSpace {
+    unsigned Generic, Global, Local, Constant, Private;
+    bool UseNew;
+    AddrSpace(bool UseNew_ = false){
+      reset(UseNew_);
+    }
+    void reset(bool UseNew_) {
+      UseNew = UseNew_;
+      if (UseNew) {
+        Generic   = 0;
+        Global    = 1;
+        Local     = 3;
+        Constant  = 4;
+        Private   = 5;
+      } else {
+        Generic   = 4;
+        Global    = 1;
+        Local     = 3;
+        Constant  = 2;
+        Private   = 0;
+      }
+    }
+    const LangAS::Map *getMap() {
+      static LangAS::Map OldMap = {
+          1,  // opencl_global
+          3,  // opencl_local
+          2,  // opencl_constant
+          4,  // opencl_generic
+          1,  // cuda_device
+          2,  // cuda_constant
+          3   // cuda_shared
+      };
+      static LangAS::Map NewMap = {
+          1,  // opencl_global
+          3,  // opencl_local
+          4,  // opencl_constant
+          0,  // opencl_generic
+          1,  // cuda_device
+          4,  // cuda_constant
+          3   // cuda_shared
+      };
+      return UseNew ? &NewMap : &OldMap;
+    }
+  };
+
   /// \brief The GPU profiles supported by the AMDGPU target.
   enum GPUKind {
     GK_NONE,
@@ -2044,6 +2084,7 @@
   bool hasFMAF:1;
   bool hasLDEXPF:1;
   bool hasFullSpeedFP32Denorms:1;
+  bool UseNewAddrMap:1;
 
   static bool isAMDGCN(const llvm::Triple &TT) {
     return TT.getArch() == llvm::Triple::amdgcn;
@@ -2056,17 +2097,29 @@
       hasFP64(false),
       hasFMAF(false),
       hasLDEXPF(false),
-      hasFullSpeedFP32Denorms(false){
+      hasFullSpeedFP32Denorms(false),
+      UseNewAddrMap(false){
     if (getTriple().getArch() == llvm::Triple::amdgcn) {
       hasFP64 = true;
       hasFMAF = true;
       hasLDEXPF = true;
     }
+    // At this stage, Opt.Features has not been populated yet.
+    for (auto &I:Opts.FeaturesAsWritten) {
+      if (I == "+new-addr") {
+        UseNewAddrMap = true;
+      } else if (I == "-new-addr") {
+        UseNewAddrMap = false;
+      }
+    }
+    AS.reset(UseNewAddrMap);
 
     resetDataLayout(getTriple().getArch() == llvm::Triple::amdgcn ?
-                    DataLayoutStringSI : DataLayoutStringR600);
+                    (UseNewAddrMap ? DataLayoutStringSINew :
+                        DataLayoutStringSIOld)
+                    : DataLayoutStringR600);
 
-    AddrSpaceMap = &AMDGPUAddrSpaceMap;
+    AddrSpaceMap = AS.getMap();
     UseAddrSpaceMapMangling = true;
   }
 
@@ -2074,14 +2127,10 @@
     if (GPU <= GK_CAYMAN)
       return 32;
 
-    switch(AddrSpace) {
-      default:
-        return 64;
-      case 0:
-      case 3:
-      case 5:
-        return 32;
+    if (AddrSpace == AS.Private || AddrSpace == AS.Local) {
+      return 32;
     }
+    return 64;
   }
 
   uint64_t getMaxPointerWidth() const override {
@@ -2300,6 +2349,8 @@
   uint64_t getNullPointerValue(unsigned AS) const override {
     return AS == LangAS::opencl_local ? ~0 : 0;
   }
+
+  AddrSpace AS;
 };
 
 const Builtin::Info AMDGPUTargetInfo::BuiltinInfo[] = {
Index: test/CodeGenOpenCL/amdgpu-new-addr.cl
===================================================================
--- /dev/null
+++ test/CodeGenOpenCL/amdgpu-new-addr.cl
@@ -0,0 +1,7 @@
+// RUN: %clang_cc1 %s -O0 -triple amdgcn -emit-llvm -o - | FileCheck %s
+// RUN: %clang_cc1 %s -O0 -triple amdgcn -target-feature "+new-addr" -emit-llvm -o - | FileCheck -check-prefix=NEW %s
+
+// CHECK: target datalayout = "e-p:32:32-p1:64:64-p2:64:64-p3:32:32-p4:64:64-p5:32:32-i64:64-v16:16-v24:32-v32:32-v48:64-v96:128-v192:256-v256:256-v512:512-v1024:1024-v2048:2048-n32:64"
+// NEW: target datalayout = "e-p:64:64-p1:64:64-p2:64:64-p3:32:32-p4:64:64-p5:32:32-i64:64-v16:16-v24:32-v32:32-v48:64-v96:128-v192:256-v256:256-v512:512-v1024:1024-v2048:2048-n32:64"
+void foo(void) {}
+