diff --git a/lib/Headers/avx512fintrin.h b/lib/Headers/avx512fintrin.h
index aca2364468cc8353d7357f38d331fc0d779cb78b..7fa318129d9ff98732261efdd4e745cf5aa9f941 100644
--- a/lib/Headers/avx512fintrin.h
+++ b/lib/Headers/avx512fintrin.h
@@ -343,6 +343,31 @@ _mm512_castps512_ps128(__m512 __a)
   return __builtin_shufflevector(__a, __a, 0, 1, 2, 3);
 }
 
+
+static __inline__ __m512d __DEFAULT_FN_ATTRS
+_mm512_castpd128_pd512 (__m128d __A)
+{
+  return __builtin_shufflevector( __A, __A, 0, 1, -1, -1, -1, -1, -1, -1);
+}
+
+static __inline__ __m512 __DEFAULT_FN_ATTRS
+_mm512_castps128_ps512 (__m128 __A)
+{
+    return  __builtin_shufflevector( __A, __A, 0, 1, 2, 3, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1);
+}
+
+static __inline__ __m512i __DEFAULT_FN_ATTRS
+_mm512_castsi128_si512 (__m128i __A)
+{
+   return  __builtin_shufflevector( __A, __A, 0, 1, -1, -1, -1, -1, -1, -1);
+}
+
+static __inline__ __m512i __DEFAULT_FN_ATTRS
+_mm512_castsi256_si512 (__m256i __A)
+{
+   return  __builtin_shufflevector( __A, __A, 0, 1, 2, 3, -1, -1, -1, -1);
+}
+
 /* Bitwise operators */
 static __inline__ __m512i __DEFAULT_FN_ATTRS
 _mm512_and_epi32(__m512i __a, __m512i __b)
diff --git a/test/CodeGen/avx512f-builtins.c b/test/CodeGen/avx512f-builtins.c
index ffc54c747d471d49911dccce686f675fedb948d5..47371ae0443820dec014f9b2eb878d307f56abe3 100644
--- a/test/CodeGen/avx512f-builtins.c
+++ b/test/CodeGen/avx512f-builtins.c
@@ -5588,3 +5588,28 @@ __m256i test_mm512_maskz_cvttpd_epu32(__mmask8 __U, __m512d __A) {
   // CHECK: @llvm.x86.avx512.mask.cvttpd2udq.512
   return _mm512_maskz_cvttpd_epu32(__U, __A); 
 }
+
+__m512d test_mm512_castpd128_pd512(__m128d __A) {
+  // CHECK-LABEL: @test_mm512_castpd128_pd512
+  // CHECK: shufflevector <2 x double> %1, <2 x double> %2, <8 x i32> <i32 0, i32 1, i32 undef, i32 undef, i32 undef, i32 undef, i32 undef, i32 undef>
+  return _mm512_castpd128_pd512(__A); 
+}
+
+__m512 test_mm512_castps128_ps512(__m128 __A) {
+  // CHECK-LABEL: @test_mm512_castps128_ps512
+  // CHECK: shufflevector <4 x float> %1, <4 x float> %2, <16 x i32> <i32 0, i32 1, i32 2, i32 3, i32 undef, i32 undef, i32 undef, i32 undef, i32 undef, i32 undef, i32 undef, i32 undef, i32 undef, i32 undef, i32 undef, i32 undef>
+  return _mm512_castps128_ps512(__A); 
+}
+
+__m512i test_mm512_castsi128_si512(__m128i __A) {
+  // CHECK-LABEL: @test_mm512_castsi128_si512
+  // CHECK: shufflevector <2 x i64> %1, <2 x i64> %2, <8 x i32> <i32 0, i32 1, i32 undef, i32 undef, i32 undef, i32 undef, i32 undef, i32 undef>
+  return _mm512_castsi128_si512(__A); 
+}
+
+__m512i test_mm512_castsi256_si512(__m256i __A) {
+  // CHECK-LABEL: @test_mm512_castsi256_si512
+  // CHECK: shufflevector <4 x i64> %1, <4 x i64> %2, <8 x i32> <i32 0, i32 1, i32 2, i32 3, i32 undef, i32 undef, i32 undef, i32 undef>
+  return _mm512_castsi256_si512(__A); 
+}
+