diff --git a/clang/lib/Basic/Targets/OSTargets.h b/clang/lib/Basic/Targets/OSTargets.h
--- a/clang/lib/Basic/Targets/OSTargets.h
+++ b/clang/lib/Basic/Targets/OSTargets.h
@@ -674,11 +674,11 @@
     Builder.defineMacro("_IBMR2");
     Builder.defineMacro("_POWER");
 
-    Builder.defineMacro("__TOS_AIX__");
     Builder.defineMacro("_AIX");
+    Builder.defineMacro("__TOS_AIX__");
 
     if (Opts.LangStd == LangStandard::lang_c11 ||
-        Opts.LangStd == LangStandard::lang_gnu11){
+        Opts.LangStd == LangStandard::lang_gnu11) {
       Builder.defineMacro("__STDC_NO_ATOMICS__");
       Builder.defineMacro("__STDC_NO_THREADS__");
     }
diff --git a/clang/lib/Basic/Targets/PPC.cpp b/clang/lib/Basic/Targets/PPC.cpp
--- a/clang/lib/Basic/Targets/PPC.cpp
+++ b/clang/lib/Basic/Targets/PPC.cpp
@@ -92,7 +92,6 @@
   Builder.defineMacro("__ppc__");
   Builder.defineMacro("__PPC__");
   Builder.defineMacro("_ARCH_PPC");
-  Builder.defineMacro("__THW_PPC__");
   Builder.defineMacro("__powerpc__");
   Builder.defineMacro("__POWERPC__");
   if (PointerWidth == 64) {
diff --git a/clang/test/Preprocessor/init-aix.c b/clang/test/Preprocessor/init-aix.c
deleted file mode 100644
--- a/clang/test/Preprocessor/init-aix.c
+++ /dev/null
@@ -1,12 +0,0 @@
-// RUN: %clang_cc1 -E -dM < /dev/null | FileCheck -match-full-lines -check-prefix AIX %s
-// AIX:#define __THW_PPC__ 1
-// AIX:#define __TOS_AIX__ 1
-// AIX-NOT:#define __STDC_NO_ATOMICS__ 1
-// AIX-NOT:#define __STDC_NO_THREADS__ 1
-//
-// RUN: %clang_cc1 -x c -std=c11 -E -dM < /dev/null | FileCheck -match-full-lines -check-prefix AIX-STDC %s
-// RUN: %clang_cc1 -x c -std=c1x -E -dM < /dev/null | FileCheck -match-full-lines -check-prefix AIX-STDC %s
-// RUN: %clang_cc1 -x c -std=iso9899:2011 -E -dM < /dev/null | FileCheck -match-full-lines -check-prefix AIX-STDC %s
-// RUN: %clang_cc1 -x c -std=gnu11 -E -dM < /dev/null | FileCheck -match-full-lines -check-prefix AIX-STDC %s
-// AIX-STDC:#define __STDC_NO_ATOMICS__ 1
-// AIX-STDC:#define __STDC_NO_THREADS__ 1
diff --git a/clang/test/Preprocessor/init-ppc.c b/clang/test/Preprocessor/init-ppc.c
--- a/clang/test/Preprocessor/init-ppc.c
+++ b/clang/test/Preprocessor/init-ppc.c
@@ -541,6 +541,9 @@
 // PPC-AIX:#define __SIZE_MAX__ 4294967295UL
 // PPC-AIX:#define __SIZE_TYPE__ long unsigned int
 // PPC-AIX:#define __SIZE_WIDTH__ 32
+// PPC-AIX-NOT:#define __STDC_NO_ATOMICS__ 1
+// PPC-AIX-NOT:#define __STDC_NO_THREADS__ 1
+// PPC-AIX:#define __TOS_AIX__ 1
 // PPC-AIX:#define __UINT16_C_SUFFIX__
 // PPC-AIX:#define __UINT16_MAX__ 65535
 // PPC-AIX:#define __UINT16_TYPE__ unsigned short
@@ -723,6 +726,13 @@
 // RUN: %clang_cc1 -E -dM -ffreestanding -triple=powerpc-ibm-aix7.1.0.0 -fno-signed-char < /dev/null | FileCheck -match-full-lines -check-prefix PPC-AIX-NOTHREADSAFE %s
 // PPC-AIX-NOTHREADSAFE-NOT:#define _THREAD_SAFE 1
 
+// RUN: %clang_cc1 -x c -std=c11 -E -dM -ffreestanding -triple=powerpc-ibm-aix7.1.0.0 -fno-signed-char < /dev/null | FileCheck -match-full-lines -check-prefix PPC-AIX-STDC %s
+// RUN: %clang_cc1 -x c -std=c1x -E -dM -ffreestanding -triple=powerpc-ibm-aix7.1.0.0 -fno-signed-char < /dev/null | FileCheck -match-full-lines -check-prefix PPC-AIX-STDC %s
+// RUN: %clang_cc1 -x c -std=iso9899:2011 -E -dM -ffreestanding -triple=powerpc-ibm-aix7.10.0 -fno-signed-char  < /dev/null | FileCheck -match-full-lines -check-prefix PPC-AIX-STDC %s
+// RUN: %clang_cc1 -x c -std=gnu11 -E -dM -ffreestanding -triple=powerpc-ibm-aix7.1.0.0 -fno-signed-char  < /dev/null | FileCheck -match-full-lines -check-prefix PPC-AIX-STDC %s
+// PPC-AIX-STDC:#define __STDC_NO_ATOMICS__ 1
+// PPC-AIX-STDC:#define __STDC_NO_THREADS__ 1
+
 // RUN: %clang_cc1 -E -dM -ffreestanding -triple=powerpc-unknown-linux-gnu -fno-signed-char < /dev/null | FileCheck -match-full-lines -check-prefix PPC-LINUX %s
 //
 // PPC-LINUX:#define _ARCH_PPC 1