diff --git a/clang/include/clang/Basic/BuiltinsX86.td b/clang/include/clang/Basic/BuiltinsX86.td
index cd5f2c3012712..cb08e2107f072 100644
--- a/clang/include/clang/Basic/BuiltinsX86.td
+++ b/clang/include/clang/Basic/BuiltinsX86.td
@@ -311,7 +311,7 @@ let Features = "sse3", Attributes = [NoThrow, RequiredVectorWidth<128>] in {
   def lddqu : X86Builtin<"_Vector<16, char>(char const *)">;
 }
 
-let Features = "ssse3", Attributes = [NoThrow, Const, RequiredVectorWidth<128>] in {
+let Features = "ssse3", Attributes = [NoThrow, Const, Constexpr, RequiredVectorWidth<128>] in {
   def palignr128 : X86Builtin<"_Vector<16, char>(_Vector<16, char>, _Vector<16, char>, _Constant int)">;
 }
 
@@ -605,8 +605,7 @@ let Features = "avx", Attributes = [NoThrow, Const, Constexpr, RequiredVectorWid
 
 let Features = "avx2", Attributes = [NoThrow, Const, RequiredVectorWidth<256>] in {
   def mpsadbw256 : X86Builtin<"_Vector<32, char>(_Vector<32, char>, _Vector<32, char>, _Constant char)">;
-  def palignr256 : X86Builtin<"_Vector<32, char>(_Vector<32, char>, "
-                              "_Vector<32, char>, _Constant int)">;
+
   def psadbw256
       : X86Builtin<
             "_Vector<4, long long int>(_Vector<32, char>, _Vector<32, char>)">;
@@ -630,6 +629,7 @@ let Features = "avx2", Attributes = [NoThrow, Const, Constexpr, RequiredVectorWi
   def pmovmskb256 : X86Builtin<"int(_Vector<32, char>)">;
   def pavgb256 : X86Builtin<"_Vector<32, unsigned char>(_Vector<32, unsigned char>, _Vector<32, unsigned char>)">;
   def pavgw256 : X86Builtin<"_Vector<16, unsigned short>(_Vector<16, unsigned short>, _Vector<16, unsigned short>)">;
+  def palignr256 : X86Builtin<"_Vector<32, char>(_Vector<32, char>, _Vector<32, char>, _Constant int)">;
 
   def pblendd128 : X86Builtin<"_Vector<4, int>(_Vector<4, int>, _Vector<4, int>, _Constant int)">;
   def pblendd256 : X86Builtin<"_Vector<8, int>(_Vector<8, int>, _Vector<8, int>, _Constant int)">;
@@ -3263,7 +3263,7 @@ let Features = "avx512bw", Attributes = [NoThrow, Const] in {
   def kmovq : X86Builtin<"unsigned long long int(unsigned long long int)">;
 }
 
-let Features = "avx512bw", Attributes = [NoThrow, Const, RequiredVectorWidth<512>] in {
+let Features = "avx512bw", Attributes = [NoThrow, Const, Constexpr, RequiredVectorWidth<512>] in {
   def palignr512 : X86Builtin<"_Vector<64, char>(_Vector<64, char>, _Vector<64, char>, _Constant int)">;
 }
 
diff --git a/clang/lib/AST/ByteCode/InterpBuiltin.cpp b/clang/lib/AST/ByteCode/InterpBuiltin.cpp
index 0ef130c0a55df..9c82196c2911a 100644
--- a/clang/lib/AST/ByteCode/InterpBuiltin.cpp
+++ b/clang/lib/AST/ByteCode/InterpBuiltin.cpp
@@ -4754,6 +4754,30 @@ bool InterpretBuiltin(InterpState &S, CodePtr OpPC, const CallExpr *Call,
           return APInt(8, 0);
         });
 
+  case X86::BI__builtin_ia32_palignr128:
+  case X86::BI__builtin_ia32_palignr256:
+  case X86::BI__builtin_ia32_palignr512:
+    return interp__builtin_ia32_shuffle_generic(
+        S, OpPC, Call, [](unsigned DstIdx, unsigned Shift) {
+          // Default to -1 → zero-fill this destination element
+          unsigned VecIdx = 1;
+          int ElemIdx = -1;
+
+          int Lane = DstIdx / 16;
+          int Offset = DstIdx % 16;
+
+          // Elements come from VecB first, then VecA after the shift boundary
+          unsigned ShiftedIdx = Offset + (Shift & 0xFF);
+          if (ShiftedIdx < 16) { // from VecB
+            ElemIdx = ShiftedIdx + (Lane * 16);
+          } else if (ShiftedIdx < 32) { // from VecA
+            VecIdx = 0;
+            ElemIdx = (ShiftedIdx - 16) + (Lane * 16);
+          }
+
+          return std::pair<unsigned, int>{VecIdx, ElemIdx};
+        });
+
   default:
     S.FFDiag(S.Current->getLocation(OpPC),
              diag::note_invalid_subexpr_in_const_expr)
diff --git a/clang/lib/AST/ExprConstant.cpp b/clang/lib/AST/ExprConstant.cpp
index 972d9fe3b5e4f..8c47f06291f34 100644
--- a/clang/lib/AST/ExprConstant.cpp
+++ b/clang/lib/AST/ExprConstant.cpp
@@ -12124,8 +12124,17 @@ static bool evalShuffleGeneric(
     if (SrcIdx < 0) {
       // Zero out this element
       QualType ElemTy = VT->getElementType();
-      ResultElements.push_back(
-          APValue(APFloat::getZero(Info.Ctx.getFloatTypeSemantics(ElemTy))));
+      if (ElemTy->isRealFloatingType()) {
+        ResultElements.push_back(
+            APValue(APFloat::getZero(Info.Ctx.getFloatTypeSemantics(ElemTy))));
+      } else if (ElemTy->isIntegerType()) {
+        APValue Zero(Info.Ctx.MakeIntValue(0, ElemTy));
+        ResultElements.push_back(APValue(Zero));
+      } else {
+        // Other types of fallback logic
+        ResultElements.push_back(APValue());
+      }
+
     } else {
       const APValue &Src = (SrcVecIdx == 0) ? A : B;
       ResultElements.push_back(Src.getVectorElt(SrcIdx));
@@ -13556,6 +13565,33 @@ bool VectorExprEvaluator::VisitCallExpr(const CallExpr *E) {
 
     return Success(APValue(ResultElements.data(), ResultElements.size()), E);
   }
+
+  case X86::BI__builtin_ia32_palignr128:
+  case X86::BI__builtin_ia32_palignr256:
+  case X86::BI__builtin_ia32_palignr512: {
+    APValue R;
+    if (!evalShuffleGeneric(Info, E, R, [](unsigned DstIdx, unsigned Shift) {
+          // Default to -1 → zero-fill this destination element
+          unsigned VecIdx = 1;
+          int ElemIdx = -1;
+
+          int Lane = DstIdx / 16;
+          int Offset = DstIdx % 16;
+
+          // Elements come from VecB first, then VecA after the shift boundary
+          unsigned ShiftedIdx = Offset + (Shift & 0xFF);
+          if (ShiftedIdx < 16) { // from VecB
+            ElemIdx = ShiftedIdx + (Lane * 16);
+          } else if (ShiftedIdx < 32) { // from VecA
+            VecIdx = 0;
+            ElemIdx = (ShiftedIdx - 16) + (Lane * 16);
+          }
+
+          return std::pair<unsigned, int>{VecIdx, ElemIdx};
+        }))
+      return false;
+    return Success(R, E);
+  }
   case X86::BI__builtin_ia32_vpermi2varq128:
   case X86::BI__builtin_ia32_vpermi2varpd128: {
     APValue R;
diff --git a/clang/test/CodeGen/X86/avx2-builtins.c b/clang/test/CodeGen/X86/avx2-builtins.c
index de4cb2fd0b055..ce8e2f04e487c 100644
--- a/clang/test/CodeGen/X86/avx2-builtins.c
+++ b/clang/test/CodeGen/X86/avx2-builtins.c
@@ -109,6 +109,9 @@ __m256i test_mm256_alignr_epi8(__m256i a, __m256i b) {
   // CHECK: shufflevector <32 x i8> %{{.*}}, <32 x i8> %{{.*}}, <32 x i32> <i32 2, i32 3, i32 4, i32 5, i32 6, i32 7, i32 8, i32 9, i32 10, i32 11, i32 12, i32 13, i32 14, i32 15, i32 32, i32 33, i32 18, i32 19, i32 20, i32 21, i32 22, i32 23, i32 24, i32 25, i32 26, i32 27, i32 28, i32 29, i32 30, i32 31, i32 48, i32 49>
   return _mm256_alignr_epi8(a, b, 2);
 }
+TEST_CONSTEXPR(match_v32qi(_mm256_alignr_epi8(((__m256i)(__v32qs){1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32}), ((__m256i)(__v32qs){33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64}), 2), 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 1, 2, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 17, 18));
+TEST_CONSTEXPR(match_v32qi(_mm256_alignr_epi8(((__m256i)(__v32qs){1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32}), ((__m256i)(__v32qs){33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64}), 16), 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32));
+TEST_CONSTEXPR(match_v32qi(_mm256_alignr_epi8(((__m256i)(__v32qs){1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32}), ((__m256i)(__v32qs){33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64}), 32), 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0));
 
 __m256i test2_mm256_alignr_epi8(__m256i a, __m256i b) {
   // CHECK-LABEL: test2_mm256_alignr_epi8
diff --git a/clang/test/CodeGen/X86/avx512bw-builtins.c b/clang/test/CodeGen/X86/avx512bw-builtins.c
index 0b73c7b14d869..2749dc5741b58 100644
--- a/clang/test/CodeGen/X86/avx512bw-builtins.c
+++ b/clang/test/CodeGen/X86/avx512bw-builtins.c
@@ -3057,6 +3057,9 @@ __m512i test_mm512_alignr_epi8(__m512i __A,__m512i __B){
     // CHECK: shufflevector <64 x i8> %{{.*}}, <64 x i8> %{{.*}}, <64 x i32> <i32 2, i32 3, i32 4, i32 5, i32 6, i32 7, i32 8, i32 9, i32 10, i32 11, i32 12, i32 13, i32 14, i32 15, i32 64, i32 65, i32 18, i32 19, i32 20, i32 21, i32 22, i32 23, i32 24, i32 25, i32 26, i32 27, i32 28, i32 29, i32 30, i32 31, i32 80, i32 81, i32 34, i32 35, i32 36, i32 37, i32 38, i32 39, i32 40, i32 41, i32 42, i32 43, i32 44, i32 45, i32 46, i32 47, i32 96, i32 97, i32 50, i32 51, i32 52, i32 53, i32 54, i32 55, i32 56, i32 57, i32 58, i32 59, i32 60, i32 61, i32 62, i32 63, i32 112, i32 113>
     return _mm512_alignr_epi8(__A, __B, 2); 
 }
+TEST_CONSTEXPR(match_v64qi(_mm512_alignr_epi8(((__m512i)(__v64qs){1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64}), ((__m512i)(__v64qs){65, 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, 80, 81, 82, 83, 84, 85, 86, 87, 88, 89, 90, 91, 92, 93, 94, 95, 96, 97, 98, 99, 100, 101, 102, 103, 104, 105, 106, 107, 108, 109, 110, 111, 112, 113, 114, 115, 116, 117, 118, 119, 120, 121, 122, 123, 124, 125, 126, 127, 127}), 2), 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, 80, 1, 2, 83, 84, 85, 86, 87, 88, 89, 90, 91, 92, 93, 94, 95, 96, 17, 18, 99, 100, 101, 102, 103, 104, 105, 106, 107, 108, 109, 110, 111, 112, 33, 34, 115, 116, 117, 118, 119, 120, 121, 122, 123, 124, 125, 126, 127, 127, 49, 50));
+TEST_CONSTEXPR(match_v64qi(_mm512_alignr_epi8(((__m512i)(__v64qs){1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64}), ((__m512i)(__v64qs){65, 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, 80, 81, 82, 83, 84, 85, 86, 87, 88, 89, 90, 91, 92, 93, 94, 95, 96, 97, 98, 99, 100, 101, 102, 103, 104, 105, 106, 107, 108, 109, 110, 111, 112, 113, 114, 115, 116, 117, 118, 119, 120, 121, 122, 123, 124, 125, 126, 127, 127}), 16), 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64));
+TEST_CONSTEXPR(match_v64qi(_mm512_alignr_epi8(((__m512i)(__v64qs){1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64}), ((__m512i)(__v64qs){65, 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, 80, 81, 82, 83, 84, 85, 86, 87, 88, 89, 90, 91, 92, 93, 94, 95, 96, 97, 98, 99, 100, 101, 102, 103, 104, 105, 106, 107, 108, 109, 110, 111, 112, 113, 114, 115, 116, 117, 118, 119, 120, 121, 122, 123, 124, 125, 126, 127, 127}), 32), 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0));
 
 __m512i test_mm512_mask_alignr_epi8(__m512i __W, __mmask64 __U, __m512i __A,__m512i __B){
     // CHECK-LABEL: test_mm512_mask_alignr_epi8
@@ -3064,6 +3067,7 @@ __m512i test_mm512_mask_alignr_epi8(__m512i __W, __mmask64 __U, __m512i __A,__m5
     // CHECK: select <64 x i1> %{{.*}}, <64 x i8> %{{.*}}, <64 x i8> %{{.*}}
     return _mm512_mask_alignr_epi8(__W, __U, __A, __B, 2); 
 }
+TEST_CONSTEXPR(match_v64qi(_mm512_mask_alignr_epi8(((__m512i)(__v64qs){127, 127, 127, 127, 127, 127, 127, 127, 127, 127, 127, 127, 127, 127, 127, 127, 127, 127, 127, 127, 127, 127, 127, 127, 127, 127, 127, 127, 127, 127, 127, 127, 127, 127, 127, 127, 127, 127, 127, 127, 127, 127, 127, 127, 127, 127, 127, 127, 127, 127, 127, 127, 127, 127, 127, 127, 127, 127, 127, 127, 127, 127, 127, 127}), (__mmask64)0x000000000000000f, ((__m512i)(__v64qs){1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64}), ((__m512i)(__v64qs){65, 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, 80, 81, 82, 83, 84, 85, 86, 87, 88, 89, 90, 91, 92, 93, 94, 95, 96, 97, 98, 99, 100, 101, 102, 103, 104, 105, 106, 107, 108, 109, 110, 111, 112, 113, 114, 115, 116, 117, 118, 119, 120, 121, 122, 123, 124, 125, 126, 127, 127}), 2), 67, 68, 69, 70, 127, 127, 127, 127, 127, 127, 127, 127, 127, 127, 127, 127, 127, 127, 127, 127, 127, 127, 127, 127, 127, 127, 127, 127, 127, 127, 127, 127, 127, 127, 127, 127, 127, 127, 127, 127, 127, 127, 127, 127, 127, 127, 127, 127, 127, 127, 127, 127, 127, 127, 127, 127, 127, 127, 127, 127, 127, 127, 127, 127));
 
 __m512i test_mm512_maskz_alignr_epi8(__mmask64 __U, __m512i __A,__m512i __B){
     // CHECK-LABEL: test_mm512_maskz_alignr_epi8
@@ -3071,6 +3075,7 @@ __m512i test_mm512_maskz_alignr_epi8(__mmask64 __U, __m512i __A,__m512i __B){
     // CHECK: select <64 x i1> %{{.*}}, <64 x i8> %{{.*}}, <64 x i8> %{{.*}}
    return _mm512_maskz_alignr_epi8(__U, __A, __B, 2); 
 }
+TEST_CONSTEXPR(match_v64qi(_mm512_maskz_alignr_epi8((__mmask64)0x000000000000000f, ((__m512i)(__v64qs){1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64}), ((__m512i)(__v64qs){65, 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, 80, 81, 82, 83, 84, 85, 86, 87, 88, 89, 90, 91, 92, 93, 94, 95, 96, 97, 98, 99, 100, 101, 102, 103, 104, 105, 106, 107, 108, 109, 110, 111, 112, 113, 114, 115, 116, 117, 118, 119, 120, 121, 122, 123, 124, 125, 126, 127, 127}), 2), 67, 68, 69, 70, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,  0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,  0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0));
 
 
 
diff --git a/clang/test/CodeGen/X86/avx512vlbw-builtins.c b/clang/test/CodeGen/X86/avx512vlbw-builtins.c
index 28e6afbc24564..7a5af2dc8742f 100644
--- a/clang/test/CodeGen/X86/avx512vlbw-builtins.c
+++ b/clang/test/CodeGen/X86/avx512vlbw-builtins.c
@@ -3538,6 +3538,7 @@ __m128i test_mm_mask_alignr_epi8(__m128i __W, __mmask16 __U, __m128i __A, __m128
   // CHECK: select <16 x i1> %{{.*}}, <16 x i8> %{{.*}}, <16 x i8> %{{.*}}
   return _mm_mask_alignr_epi8(__W, __U, __A, __B, 2); 
 }
+TEST_CONSTEXPR(match_v16qi(_mm_mask_alignr_epi8(((__m128i)(__v16qs){127, 127, 127, 127, 127, 127, 127, 127, 127, 127, 127, 127, 127, 127, 127, 127}), (__mmask16)0x000f, ((__m128i)(__v16qs){1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16}), ((__m128i)(__v16qs){17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32}), 2), 19, 20, 21, 22, 127, 127, 127, 127, 127, 127, 127, 127, 127, 127, 127, 127));
 
 __m128i test_mm_maskz_alignr_epi8(__mmask16 __U, __m128i __A, __m128i __B) {
   // CHECK-LABEL: test_mm_maskz_alignr_epi8
@@ -3545,6 +3546,7 @@ __m128i test_mm_maskz_alignr_epi8(__mmask16 __U, __m128i __A, __m128i __B) {
   // CHECK: select <16 x i1> %{{.*}}, <16 x i8> %{{.*}}, <16 x i8> %{{.*}}
   return _mm_maskz_alignr_epi8(__U, __A, __B, 2); 
 }
+TEST_CONSTEXPR(match_v16qi( _mm_maskz_alignr_epi8((__mmask16)0x000f, ((__m128i)(__v16qs){1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16}), ((__m128i)(__v16qs){17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32}),2), 19, 20, 21, 22, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0));
 
 __m256i test_mm256_mask_alignr_epi8(__m256i __W, __mmask32 __U, __m256i __A, __m256i __B) {
   // CHECK-LABEL: test_mm256_mask_alignr_epi8
@@ -3552,6 +3554,7 @@ __m256i test_mm256_mask_alignr_epi8(__m256i __W, __mmask32 __U, __m256i __A, __m
   // CHECK: select <32 x i1> %{{.*}}, <32 x i8> %{{.*}}, <32 x i8> %{{.*}}
   return _mm256_mask_alignr_epi8(__W, __U, __A, __B, 2); 
 }
+TEST_CONSTEXPR(match_v32qi(_mm256_mask_alignr_epi8(((__m256i)(__v32qs){127, 127, 127, 127, 127, 127, 127, 127, 127, 127, 127, 127, 127, 127, 127, 127, 127, 127, 127, 127, 127, 127, 127, 127, 127, 127, 127, 127, 127, 127, 127, 127}), (__mmask32)0xf000000f, ((__m256i)(__v32qs){1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32}), ((__m256i)(__v32qs){33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64}), 2), 35, 36, 37, 38, 127, 127, 127, 127, 127, 127, 127, 127, 127, 127, 127, 127, 127, 127, 127, 127, 127, 127, 127, 127, 127, 127, 127, 127, 63, 64, 17, 18));
 
 __m256i test_mm256_maskz_alignr_epi8(__mmask32 __U, __m256i __A, __m256i __B) {
   // CHECK-LABEL: test_mm256_maskz_alignr_epi8
@@ -3559,6 +3562,7 @@ __m256i test_mm256_maskz_alignr_epi8(__mmask32 __U, __m256i __A, __m256i __B) {
   // CHECK: select <32 x i1> %{{.*}}, <32 x i8> %{{.*}}, <32 x i8> %{{.*}}
   return _mm256_maskz_alignr_epi8(__U, __A, __B, 2); 
 }
+TEST_CONSTEXPR(match_v32qi(_mm256_maskz_alignr_epi8((__mmask32)0xf000000f, ((__m256i)(__v32qs){1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32}), ((__m256i)(__v32qs){33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64}), 2), 35, 36, 37, 38, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 63, 64, 17, 18));
 
 __m128i test_mm_dbsad_epu8(__m128i __A, __m128i __B) {
   // CHECK-LABEL: test_mm_dbsad_epu8
diff --git a/clang/test/CodeGen/X86/mmx-builtins.c b/clang/test/CodeGen/X86/mmx-builtins.c
index 273138063a1b1..ad8a81c61ad43 100644
--- a/clang/test/CodeGen/X86/mmx-builtins.c
+++ b/clang/test/CodeGen/X86/mmx-builtins.c
@@ -102,6 +102,8 @@ __m64 test_mm_alignr_pi8(__m64 a, __m64 b) {
   // CHECK: shufflevector <16 x i8> {{%.*}}, <16 x i8> zeroinitializer, <16 x i32> <i32 2, i32 3, i32 4, i32 5, i32 6, i32 7, i32 8, i32 9, i32 10, i32 11, i32 12, i32 13, i32 14, i32 15, i32 16, i32 17>
   return _mm_alignr_pi8(a, b, 2);
 }
+TEST_CONSTEXPR(match_v8qi(_mm_alignr_pi8(((__m64)(__v8qs){1, 2, 3, 4, 5, 6, 7, 8}), ((__m64)(__v8qs){9, 10, 11, 12, 13, 14, 15, 16}), 2), 11, 12, 13, 14, 15, 16, 1, 2));
+TEST_CONSTEXPR(match_v8qi(_mm_alignr_pi8(((__m64)(__v8qs){1, 2, 3, 4, 5, 6, 7, 8}), ((__m64)(__v8qs){9, 10, 11, 12, 13, 14, 15, 16}), 16), 0, 0, 0, 0, 0, 0, 0, 0));
 
 __m64 test_mm_and_si64(__m64 a, __m64 b) {
   // CHECK-LABEL: test_mm_and_si64
diff --git a/clang/test/CodeGen/X86/ssse3-builtins.c b/clang/test/CodeGen/X86/ssse3-builtins.c
index b7a4a2fe7ccd7..193fa37f65d14 100644
--- a/clang/test/CodeGen/X86/ssse3-builtins.c
+++ b/clang/test/CodeGen/X86/ssse3-builtins.c
@@ -48,6 +48,8 @@ __m128i test_mm_alignr_epi8(__m128i a, __m128i b) {
   // CHECK: shufflevector <16 x i8> %{{.*}}, <16 x i8> %{{.*}}, <16 x i32> <i32 2, i32 3, i32 4, i32 5, i32 6, i32 7, i32 8, i32 9, i32 10, i32 11, i32 12, i32 13, i32 14, i32 15, i32 16, i32 17>
   return _mm_alignr_epi8(a, b, 2);
 }
+TEST_CONSTEXPR(match_v16qi(_mm_alignr_epi8(((__m128i)(__v16qi){1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16}), ((__m128i)(__v16qi){17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32}), 2), 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 1, 2));
+TEST_CONSTEXPR(match_v16qi(_mm_alignr_epi8(((__m128i)(__v16qi){1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16}), ((__m128i)(__v16qi){17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32}), 32), 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0));
 
 __m128i test2_mm_alignr_epi8(__m128i a, __m128i b) {
   // CHECK-LABEL: test2_mm_alignr_epi8