diff --git a/clang/include/clang/Basic/DiagnosticSemaKinds.td b/clang/include/clang/Basic/DiagnosticSemaKinds.td
--- a/clang/include/clang/Basic/DiagnosticSemaKinds.td
+++ b/clang/include/clang/Basic/DiagnosticSemaKinds.td
@@ -259,6 +259,9 @@
 def err_invalid_vector_double_decl_spec : Error <
   "use of 'double' with '__vector' requires VSX support to be enabled "
   "(available on POWER7 or later)">;
+def err_invalid_vector_bool_int128_decl_spec : Error <
+  "use of '__int128' with '__vector bool' requires VSX support enabled (on "
+  "POWER10 or later)">;
 def err_invalid_vector_long_long_decl_spec : Error <
   "use of 'long long' with '__vector bool' requires VSX support (available on "
   "POWER7 or later) or extended Altivec support (available on POWER8 or later) "
diff --git a/clang/lib/Sema/DeclSpec.cpp b/clang/lib/Sema/DeclSpec.cpp
--- a/clang/lib/Sema/DeclSpec.cpp
+++ b/clang/lib/Sema/DeclSpec.cpp
@@ -1150,14 +1150,20 @@
         S.Diag(TSSLoc, diag::err_invalid_vector_bool_decl_spec)
           << getSpecifierName((TSS)TypeSpecSign);
       }
-
-      // Only char/int are valid with vector bool. (PIM 2.1)
+      // Only char/int are valid with vector bool prior to Power10.
+      // Power10 adds instructions that produce vector bool data
+      // for quadwords as well so allow vector bool __int128.
       if (((TypeSpecType != TST_unspecified) && (TypeSpecType != TST_char) &&
-           (TypeSpecType != TST_int)) || TypeAltiVecPixel) {
+           (TypeSpecType != TST_int) && (TypeSpecType != TST_int128)) ||
+          TypeAltiVecPixel) {
         S.Diag(TSTLoc, diag::err_invalid_vector_bool_decl_spec)
           << (TypeAltiVecPixel ? "__pixel" :
                                  getSpecifierName((TST)TypeSpecType, Policy));
       }
+      // vector bool __int128 requires Power10.
+      if ((TypeSpecType == TST_int128) &&
+          (!S.Context.getTargetInfo().hasFeature("power10-vector")))
+        S.Diag(TSTLoc, diag::err_invalid_vector_bool_int128_decl_spec);
 
       // Only 'short' and 'long long' are valid with vector bool. (PIM 2.1)
       if ((TypeSpecWidth != TSW_unspecified) && (TypeSpecWidth != TSW_short) &&
@@ -1174,7 +1180,7 @@
 
       // Elements of vector bool are interpreted as unsigned. (PIM 2.1)
       if ((TypeSpecType == TST_char) || (TypeSpecType == TST_int) ||
-          (TypeSpecWidth != TSW_unspecified))
+          (TypeSpecType == TST_int128) || (TypeSpecWidth != TSW_unspecified))
         TypeSpecSign = TSS_unsigned;
     } else if (TypeSpecType == TST_double) {
       // vector long double and vector long long double are never allowed.
diff --git a/clang/test/Parser/altivec-bool-128.c b/clang/test/Parser/altivec-bool-128.c
new file mode 100644
--- /dev/null
+++ b/clang/test/Parser/altivec-bool-128.c
@@ -0,0 +1,21 @@
+// RUN: %clang_cc1 -triple=powerpc64-unknown-linux-gnu \
+// RUN:            -target-feature +altivec -fsyntax-only -verify %s
+// RUN: %clang_cc1 -triple=powerpc64le-unknown-linux-gnu \
+// RUN:            -target-feature +altivec -fsyntax-only -verify %s
+// RUN: %clang_cc1 -triple=powerpc64le-unknown-linux-gnu -target-cpu pwr10 \
+// RUN:            -target-feature +altivec -target-feature +vsx \
+// RUN:            -target-feature -power10-vector -fsyntax-only -verify %s
+
+// Test 'vector bool __int128' type.
+
+// These should have errors.
+__vector bool __int128 v1_bi128;          // expected-error {{use of '__int128' with '__vector bool' requires VSX support enabled (on POWER10 or later)}}
+__vector __bool __int128 v2_bi128;        // expected-error {{use of '__int128' with '__vector bool' requires VSX support enabled (on POWER10 or later)}}
+vector bool __int128 v3_bi128;            // expected-error {{use of '__int128' with '__vector bool' requires VSX support enabled (on POWER10 or later)}}
+vector __bool __int128 v4_bi128;          // expected-error {{use of '__int128' with '__vector bool' requires VSX support enabled (on POWER10 or later)}}
+__vector bool unsigned __int128 v5_bi128; // expected-error {{cannot use 'unsigned' with '__vector bool'}} expected-error {{use of '__int128' with '__vector bool' requires VSX support enabled (on POWER10 or later)}}
+__vector bool signed __int128 v6_bi128;   // expected-error {{cannot use 'signed' with '__vector bool'}} expected-error {{use of '__int128' with '__vector bool' requires VSX support enabled (on POWER10 or later)}}
+vector bool unsigned __int128 v7_bi128;   // expected-error {{cannot use 'unsigned' with '__vector bool'}} expected-error {{use of '__int128' with '__vector bool' requires VSX support enabled (on POWER10 or later)}}
+vector bool signed __int128 v8_bi128;     // expected-error {{cannot use 'signed' with '__vector bool'}} expected-error {{use of '__int128' with '__vector bool' requires VSX support enabled (on POWER10 or later)}}
+__vector __bool signed __int128 v9_bi128; // expected-error {{cannot use 'signed' with '__vector bool'}} expected-error {{use of '__int128' with '__vector bool' requires VSX support enabled (on POWER10 or later)}}
+vector __bool signed __int128 v10_bi128;  // expected-error {{cannot use 'signed' with '__vector bool'}} expected-error {{use of '__int128' with '__vector bool' requires VSX support enabled (on POWER10 or later)}}
diff --git a/clang/test/Parser/cxx-altivec-bool-128.cpp b/clang/test/Parser/cxx-altivec-bool-128.cpp
new file mode 100644
--- /dev/null
+++ b/clang/test/Parser/cxx-altivec-bool-128.cpp
@@ -0,0 +1,23 @@
+// RUN: %clang_cc1 -triple=powerpc64-unknown-linux-gnu \
+// RUN:            -target-feature +altivec -fsyntax-only -verify -std=c++11 %s
+// RUN: %clang_cc1 -triple=powerpc64le-unknown-linux-gnu \
+// RUN:            -target-feature +altivec -fsyntax-only -verify -std=c++11 %s
+// RUN: %clang_cc1 -triple=powerpc64le-unknown-linux-gnu -target-cpu pwr10 \
+// RUN:            -target-feature +altivec -target-feature +vsx \
+// RUN:            -target-feature -power10-vector -fsyntax-only -verify %s
+
+#include <altivec.h>
+
+// Test 'vector bool __int128' type.
+
+// These should have errors.
+__vector bool __int128 v1_bi128;          // expected-error {{use of '__int128' with '__vector bool' requires VSX support enabled (on POWER10 or later)}}
+__vector __bool __int128 v2_bi128;        // expected-error {{use of '__int128' with '__vector bool' requires VSX support enabled (on POWER10 or later)}}
+vector bool __int128 v3_bi128;            // expected-error {{use of '__int128' with '__vector bool' requires VSX support enabled (on POWER10 or later)}}
+vector __bool __int128 v4_bi128;          // expected-error {{use of '__int128' with '__vector bool' requires VSX support enabled (on POWER10 or later)}}
+__vector bool unsigned __int128 v5_bi128; // expected-error {{cannot use 'unsigned' with '__vector bool'}} expected-error {{use of '__int128' with '__vector bool' requires VSX support enabled (on POWER10 or later)}}
+__vector bool signed __int128 v6_bi128;   // expected-error {{cannot use 'signed' with '__vector bool'}} expected-error {{use of '__int128' with '__vector bool' requires VSX support enabled (on POWER10 or later)}}
+vector bool unsigned __int128 v7_bi128;   // expected-error {{cannot use 'unsigned' with '__vector bool'}} expected-error {{use of '__int128' with '__vector bool' requires VSX support enabled (on POWER10 or later)}}
+vector bool signed __int128 v8_bi128;     // expected-error {{cannot use 'signed' with '__vector bool'}} expected-error {{use of '__int128' with '__vector bool' requires VSX support enabled (on POWER10 or later)}}
+__vector __bool signed __int128 v9_bi128; // expected-error {{cannot use 'signed' with '__vector bool'}} expected-error {{use of '__int128' with '__vector bool' requires VSX support enabled (on POWER10 or later)}}
+vector __bool signed __int128 v10_bi128;  // expected-error {{cannot use 'signed' with '__vector bool'}} expected-error {{use of '__int128' with '__vector bool' requires VSX support enabled (on POWER10 or later)}}
diff --git a/clang/test/Parser/p10-vector-bool-128.c b/clang/test/Parser/p10-vector-bool-128.c
new file mode 100644
--- /dev/null
+++ b/clang/test/Parser/p10-vector-bool-128.c
@@ -0,0 +1,12 @@
+// RUN: %clang_cc1 -triple=powerpc64-unknown-linux-gnu -target-cpu pwr10 \
+// RUN:            -target-feature +vsx -target-feature +power10-vector \
+// RUN:            -fsyntax-only -verify %s
+// RUN: %clang_cc1 -triple=powerpc64le-unknown-linux-gnu -target-cpu pwr10 \
+// RUN:            -target-feature +power10-vector -fsyntax-only -verify %s
+// expected-no-diagnostics
+
+// Test legitimate uses of 'vector bool __int128' with VSX.
+__vector bool __int128 v1_bi128;
+__vector __bool __int128 v2_bi128;
+vector bool __int128 v3_bi128;
+vector __bool __int128 v4_bi128;