Index: cfe/trunk/lib/AST/ItaniumMangle.cpp
===================================================================
--- cfe/trunk/lib/AST/ItaniumMangle.cpp
+++ cfe/trunk/lib/AST/ItaniumMangle.cpp
@@ -2648,13 +2648,8 @@
   case CC_C:
     return "";
 
-  case CC_X86StdCall:
-  case CC_X86FastCall:
-  case CC_X86ThisCall:
   case CC_X86VectorCall:
   case CC_X86Pascal:
-  case CC_Win64:
-  case CC_X86_64SysV:
   case CC_X86RegCall:
   case CC_AAPCS:
   case CC_AAPCS_VFP:
@@ -2667,6 +2662,16 @@
     // FIXME: we should be mangling all of the above.
     return "";
 
+  case CC_X86StdCall:
+    return "stdcall";
+  case CC_X86FastCall:
+    return "fastcall";
+  case CC_X86ThisCall:
+    return "thiscall";
+  case CC_X86_64SysV:
+    return "sysv_abi";
+  case CC_Win64:
+    return "ms_abi";
   case CC_Swift:
     return "swiftcall";
   }
Index: cfe/trunk/test/CodeGenCXX/mangle-win-ccs.cpp
===================================================================
--- cfe/trunk/test/CodeGenCXX/mangle-win-ccs.cpp
+++ cfe/trunk/test/CodeGenCXX/mangle-win-ccs.cpp
@@ -0,0 +1,61 @@
+// RUN: %clang_cc1 %s -emit-llvm -triple i686-windows-gnu -o - | FileCheck %s
+// RUN: %clang_cc1 %s -emit-llvm -triple i686-windows-itanium -o - | FileCheck %s
+
+// GCC 5.1 began mangling these Windows calling conventions into function
+// types, since they can be used for overloading. They've always been mangled
+// in the MS ABI, but they are new to the Itanium mangler. Note that the main
+// function definition does not use a calling convention. Only function types
+// that appear later use it.
+
+template <typename Fn> static int func_as_ptr(Fn fn) { return int(fn); }
+
+void f_cdecl(int, int);
+void __attribute__((stdcall)) f_stdcall(int, int);
+void __attribute__((fastcall)) f_fastcall(int, int);
+void __attribute__((thiscall)) f_thiscall(int, int);
+
+int as_cdecl() { return func_as_ptr(f_cdecl); }
+int as_stdcall() { return func_as_ptr(f_stdcall); }
+int as_fastcall() { return func_as_ptr(f_fastcall); }
+int as_thiscall() { return func_as_ptr(f_thiscall); }
+
+// CHECK: define dso_local i32 @_Z8as_cdeclv()
+// CHECK:   call i32 @_ZL11func_as_ptrIPFviiEEiT_(void (i32, i32)* @_Z7f_cdeclii)
+
+// CHECK: define dso_local i32 @_Z10as_stdcallv()
+// CHECK:   call i32 @_ZL11func_as_ptrIPU7stdcallFviiEEiT_(void (i32, i32)* @"\01__Z9f_stdcallii@8")
+
+// CHECK: define dso_local i32 @_Z11as_fastcallv()
+// CHECK:   call i32 @_ZL11func_as_ptrIPU8fastcallFviiEEiT_(void (i32, i32)* @"\01@_Z10f_fastcallii@8")
+
+// CHECK: define dso_local i32 @_Z11as_thiscallv()
+// CHECK:   call i32 @_ZL11func_as_ptrIPU8thiscallFviiEEiT_(void (i32, i32)* @_Z10f_thiscallii)
+
+// CHECK: define dso_local void @_Z11funcRefTypeRU8fastcallFviiE(void (i32, i32)* %fr)
+void funcRefType(void(__attribute__((fastcall)) & fr)(int, int)) {
+  fr(1, 2);
+}
+
+// CHECK: define dso_local void @_Z12memptrCCTypeR3FooMS_U8fastcallFviiE(%struct.Foo* {{.*}}, { i32, i32 }* byval{{.*}})
+struct Foo { void bar(int, int); };
+void memptrCCType(Foo &o, void (__attribute__((fastcall)) Foo::*mp)(int, int)) {
+  (o.*mp)(1, 2);
+}
+
+// CHECK: define dso_local i32 @_Z17useTemplateFnTypev()
+// CHECK:   call i32 @_ZL14templateFnTypeIU8fastcallFviiEElPT_(void (i32, i32)* @"\01@_Z10f_fastcallii@8")
+template <typename Fn> static long templateFnType(Fn *fn) { return long(fn); }
+long useTemplateFnType() { return templateFnType(f_fastcall); }
+
+// CHECK: define weak_odr dso_local x86_fastcallcc void @"\01@_Z10fnTemplateIsEvv@0"()
+// CHECK: define          dso_local x86_fastcallcc void @"\01@_Z10fnTemplateIiEvv@0"()
+template <typename T> void __attribute__((fastcall)) fnTemplate() {}
+template void __attribute__((fastcall)) fnTemplate<short>();
+template <> void __attribute__((fastcall)) fnTemplate<int>() {}
+
+// CHECK: define weak_odr dso_local x86_fastcallcc void (i32, i32)* @"\01@_Z12fnTempReturnIsEPU8fastcallFviiEv@0"()
+// CHECK: define          dso_local x86_fastcallcc void (i32, i32)* @"\01@_Z12fnTempReturnIiEPU8fastcallFviiEv@0"()
+typedef void (__attribute__((fastcall)) *fp_cc_t)(int, int);
+template <typename T> fp_cc_t __attribute__((fastcall)) fnTempReturn() { return nullptr; }
+template fp_cc_t __attribute__((fastcall)) fnTempReturn<short>();
+template <> fp_cc_t __attribute__((fastcall)) fnTempReturn<int>() { return nullptr; }
Index: cfe/trunk/test/CodeGenCXX/mangle-win64-ccs.cpp
===================================================================
--- cfe/trunk/test/CodeGenCXX/mangle-win64-ccs.cpp
+++ cfe/trunk/test/CodeGenCXX/mangle-win64-ccs.cpp
@@ -0,0 +1,26 @@
+// RUN: %clang_cc1 -triple x86_64-windows-gnu -o - -emit-llvm %s | FileCheck %s -check-prefix CHECK-WIN
+// RUN: %clang_cc1 -triple x86_64-linux-gnu -o - -emit-llvm %s | FileCheck %s -check-prefix CHECK-LIN
+
+typedef __PTRDIFF_TYPE__ ptrdiff_t;
+template <typename FTy> ptrdiff_t func_as_int(FTy *fp) { return ptrdiff_t(fp); }
+
+int f_plain(int);
+int __attribute__((sysv_abi)) f_sysvabi(int);
+int __attribute__((ms_abi)) f_msabi(int);
+ptrdiff_t useThem() {
+  ptrdiff_t rv = 0;
+  rv += func_as_int(f_plain);
+  rv += func_as_int(f_sysvabi);
+  rv += func_as_int(f_msabi);
+  return rv;
+}
+
+// CHECK-WIN: define dso_local i64 @_Z7useThemv()
+// CHECK-WIN:   call i64 @_Z11func_as_intIFiiEExPT_(i32 (i32)* @_Z7f_plaini)
+// CHECK-WIN:   call i64 @_Z11func_as_intIU8sysv_abiFiiEExPT_(i32 (i32)* @_Z9f_sysvabii)
+// CHECK-WIN:   call i64 @_Z11func_as_intIFiiEExPT_(i32 (i32)* @_Z7f_msabii)
+
+// CHECK-LIN: define i64 @_Z7useThemv()
+// CHECK-LIN:   call i64 @_Z11func_as_intIFiiEElPT_(i32 (i32)* @_Z7f_plaini)
+// CHECK-LIN:   call i64 @_Z11func_as_intIFiiEElPT_(i32 (i32)* @_Z9f_sysvabii)
+// CHECK-LIN:   call i64 @_Z11func_as_intIU6ms_abiFiiEElPT_(i32 (i32)* @_Z7f_msabii)