Index: include/clang/Basic/BuiltinsPPC.def
===================================================================
--- include/clang/Basic/BuiltinsPPC.def
+++ include/clang/Basic/BuiltinsPPC.def
@@ -336,6 +336,9 @@
 BUILTIN(__builtin_vsx_xvcpsgndp, "V2dV2dV2d", "")
 BUILTIN(__builtin_vsx_xvcpsgnsp, "V4fV4fV4f", "")
 
+BUILTIN(__builtin_vsx_xvabssp, "V4fV4f", "")
+BUILTIN(__builtin_vsx_xvabsdp, "V2dV2d", "")
+
 // HTM builtins
 BUILTIN(__builtin_tbegin, "UiUIi", "")
 BUILTIN(__builtin_tend, "UiUIi", "")
Index: lib/CodeGen/CGBuiltin.cpp
===================================================================
--- lib/CodeGen/CGBuiltin.cpp
+++ lib/CodeGen/CGBuiltin.cpp
@@ -6987,6 +6987,16 @@
     llvm::Function *F = CGM.getIntrinsic(ID, ResultType);
     return Builder.CreateCall(F, X);
   }
+
+  // Absolute value
+  case PPC::BI__builtin_vsx_xvabsdp:
+  case PPC::BI__builtin_vsx_xvabssp: {
+    llvm::Type *ResultType = ConvertType(E->getType());
+    Value *X = EmitScalarExpr(E->getArg(0));
+    llvm::Function *F = CGM.getIntrinsic(Intrinsic::fabs, ResultType);
+    return Builder.CreateCall(F, X);
+  }
+
   // FMA variations
   case PPC::BI__builtin_vsx_xvmaddadp:
   case PPC::BI__builtin_vsx_xvmaddasp:
Index: lib/Headers/altivec.h
===================================================================
--- lib/Headers/altivec.h
+++ lib/Headers/altivec.h
@@ -124,16 +124,18 @@
 #endif
 
 static vector float __ATTRS_o_ai vec_abs(vector float __a) {
+#ifdef __VSX__
+  return __builtin_vsx_xvabssp(__a);
+#else
   vector unsigned int __res =
       (vector unsigned int)__a & (vector unsigned int)(0x7FFFFFFF);
   return (vector float)__res;
+#endif
 }
 
 #if defined(__POWER8_VECTOR__) && defined(__powerpc64__)
 static vector double __ATTRS_o_ai vec_abs(vector double __a) {
-  vector unsigned long long __res = { 0x7FFFFFFFFFFFFFFF, 0x7FFFFFFFFFFFFFFF };
-  __res &= (vector unsigned int)__a;
-  return (vector double)__res;
+  return __builtin_vsx_xvabsdp(__a);
 }
 #endif
 
Index: test/CodeGen/builtins-ppc-altivec.c
===================================================================
--- test/CodeGen/builtins-ppc-altivec.c
+++ test/CodeGen/builtins-ppc-altivec.c
@@ -1,7 +1,13 @@
 // REQUIRES: powerpc-registered-target
-// RUN: %clang_cc1 -faltivec -triple powerpc-unknown-unknown -emit-llvm %s -o - | FileCheck %s
-// RUN: %clang_cc1 -faltivec -triple powerpc64-unknown-unknown -emit-llvm %s -o - | FileCheck %s
-// RUN: %clang_cc1 -faltivec -triple powerpc64le-unknown-unknown -emit-llvm %s -o - | FileCheck %s -check-prefix=CHECK-LE
+// RUN: %clang_cc1 -faltivec -triple powerpc-unknown-unknown -emit-llvm %s \
+// RUN:            -o - | FileCheck %s
+// RUN: %clang_cc1 -faltivec -triple powerpc64-unknown-unknown -emit-llvm %s \
+// RUN:            -o - | FileCheck %s
+// RUN: %clang_cc1 -faltivec -triple powerpc64le-unknown-unknown -emit-llvm %s \
+// RUN:            -o - | FileCheck %s -check-prefix=CHECK-LE
+// RUN: not %clang_cc1 -triple powerpc64le-unknown-unknown -emit-llvm %s \
+// RUN:            -ferror-limit 0 -o - 2>&1 \
+// RUN:            | FileCheck %s -check-prefix=CHECK-NOALTIVEC
 
 vector bool char vbc = { 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0 };
 vector signed char vsc = { 1, -2, 3, -4, 5, -6, 7, -8, 9, -10, 11, -12, 13, -14, 15, -16 };
@@ -27,6 +33,8 @@
 vector unsigned int res_vui;
 vector float res_vf;
 
+// CHECK-NOALTIVEC: error: unknown type name 'vector'
+
 signed char param_sc;
 unsigned char param_uc;
 short param_s;
@@ -66,8 +74,16 @@
 // CHECK-LE: @llvm.ppc.altivec.vmaxsw
 
   vf = vec_abs(vf);
-// CHECK: and <4 x i32>
-// CHECK-LE: and <4 x i32>
+// CHECK: bitcast <4 x float> %{{.*}} to <4 x i32>
+// CHECK: and <4 x i32> {{.*}}, <i32 2147483647, i32 2147483647, i32 2147483647, i32 2147483647>
+// CHECK: bitcast <4 x i32> %{{.*}} to <4 x float>
+// CHECK: store <4 x float> %{{.*}}, <4 x float>* @vf
+// CHECK-LE: bitcast <4 x float> %{{.*}} to <4 x i32>
+// CHECK-LE: and <4 x i32> {{.*}}, <i32 2147483647, i32 2147483647, i32 2147483647, i32 2147483647>
+// CHECK-LE: bitcast <4 x i32> %{{.*}} to <4 x float>
+// CHECK-LE: store <4 x float> %{{.*}}, <4 x float>* @vf
+// CHECK-NOALTIVEC: error: use of undeclared identifier 'vf'
+// CHECK-NOALTIVEC: vf = vec_abs(vf) 
 
   /* vec_abs */
   vsc = vec_abss(vsc);
Index: test/CodeGen/builtins-ppc-p8vector.c
===================================================================
--- test/CodeGen/builtins-ppc-p8vector.c
+++ test/CodeGen/builtins-ppc-p8vector.c
@@ -73,10 +73,10 @@
 // CHECK-PPC: error: call to 'vec_abs' is ambiguous
 
   res_vd = vec_abs(vda);
-// CHECK: store <2 x i64> <i64 9223372036854775807, i64 9223372036854775807>, <2 x i64>*
-// CHECK: and <2 x i64>
-// CHECK-LE: store <2 x i64> <i64 9223372036854775807, i64 9223372036854775807>, <2 x i64>*
-// CHECK-LE: and <2 x i64>
+// CHECK: call <2 x double> @llvm.fabs.v2f64(<2 x double> %{{.*}})
+// CHECK: store <2 x double> %{{.*}}, <2 x double>* @res_vd
+// CHECK-LE: call <2 x double> @llvm.fabs.v2f64(<2 x double> %{{.*}})
+// CHECK-LE: store <2 x double> %{{.*}}, <2 x double>* @res_vd
 // CHECK-PPC: error: call to 'vec_abs' is ambiguous
 
   /* vec_add */
Index: test/CodeGen/builtins-ppc-vsx.c
===================================================================
--- test/CodeGen/builtins-ppc-vsx.c
+++ test/CodeGen/builtins-ppc-vsx.c
@@ -29,6 +29,14 @@
 // CHECK-LABEL: define void @test1
 // CHECK-LE-LABEL: define void @test1
 
+  res_vf = vec_abs(vf);
+// CHECK: call <4 x float> @llvm.fabs.v4f32(<4 x float> %{{[0-9]*}})
+// CHECK-LE: call <4 x float> @llvm.fabs.v4f32(<4 x float> %{{[0-9]*}})
+
+  dummy();
+// CHECK: call void @dummy()
+// CHECK-LE: call void @dummy()
+
   res_vd = vec_add(vd, vd);
 // CHECK: fadd <2 x double>
 // CHECK-LE: fadd <2 x double>