Index: lib/Frontend/InitPreprocessor.cpp
===================================================================
--- lib/Frontend/InitPreprocessor.cpp
+++ lib/Frontend/InitPreprocessor.cpp
@@ -1113,10 +1113,18 @@
     Builder.defineMacro("__x86_64__");
     break;
   case llvm::Triple::ppc64:
+    if (AuxTI.getLongDoubleWidth() == 128) {
+      Builder.defineMacro("__LONG_DOUBLE_128__");
+      Builder.defineMacro("__LONGDOUBLE128");
+    }
     Builder.defineMacro("__powerpc64__");
     Builder.defineMacro("_CALL_ELF", "1");
     break;
   case llvm::Triple::ppc64le:
+    if (AuxTI.getLongDoubleWidth() == 128) {
+      Builder.defineMacro("__LONG_DOUBLE_128__");
+      Builder.defineMacro("__LONGDOUBLE128");
+    }
     Builder.defineMacro("__powerpc64__");
     Builder.defineMacro("_CALL_ELF", "2");
     break;