diff --git a/llvm/lib/Target/X86/X86ISelLowering.cpp b/llvm/lib/Target/X86/X86ISelLowering.cpp
index 5355053241a4..0ea98784eb3e 100644
--- a/llvm/lib/Target/X86/X86ISelLowering.cpp
+++ b/llvm/lib/Target/X86/X86ISelLowering.cpp
@@ -1556,6 +1556,7 @@ void X86TargetLowering::resetOperationActions() {
   setTargetDAGCombine(ISD::TRUNCATE);
   setTargetDAGCombine(ISD::SINT_TO_FP);
   setTargetDAGCombine(ISD::SETCC);
+  setTargetDAGCombine(ISD::INTRINSIC_WO_CHAIN);
   if (Subtarget->is64Bit())
     setTargetDAGCombine(ISD::MUL);
   setTargetDAGCombine(ISD::XOR);
@@ -11615,6 +11616,10 @@ static SDValue getTargetVShiftByConstNode(unsigned Opc, SDLoc dl, MVT VT,
                                           SelectionDAG &DAG) {
   MVT ElementType = VT.getVectorElementType();
 
+  // Fold this packed shift into its first operand if ShiftAmt is 0.
+  if (ShiftAmt == 0)
+    return SrcOp;
+
   // Check for ShiftAmt >= element width
   if (ShiftAmt >= ElementType.getSizeInBits()) {
     if (Opc == X86ISD::VSRAI)
@@ -18484,6 +18489,55 @@ static SDValue PerformCMOVCombine(SDNode *N, SelectionDAG &DAG,
   return SDValue();
 }
 
+static SDValue PerformINTRINSIC_WO_CHAINCombine(SDNode *N, SelectionDAG &DAG) {
+  unsigned IntNo = cast<ConstantSDNode>(N->getOperand(0))->getZExtValue();
+  switch (IntNo) {
+  default: return SDValue();
+  // Packed SSE2/AVX2 arithmetic shift immediate intrinsics.
+  case Intrinsic::x86_sse2_psrai_w:
+  case Intrinsic::x86_sse2_psrai_d:
+  case Intrinsic::x86_avx2_psrai_w:
+  case Intrinsic::x86_avx2_psrai_d:
+  case Intrinsic::x86_sse2_psra_w:
+  case Intrinsic::x86_sse2_psra_d:
+  case Intrinsic::x86_avx2_psra_w:
+  case Intrinsic::x86_avx2_psra_d: {
+    SDValue Op0 = N->getOperand(1);
+    SDValue Op1 = N->getOperand(2);
+    EVT VT = Op0.getValueType();
+    assert(VT.isVector() && "Expected a vector type!");
+
+    if (isa<BuildVectorSDNode>(Op1))
+      Op1 = Op1.getOperand(0);
+
+    if (!isa<ConstantSDNode>(Op1))
+      return SDValue();
+
+    EVT SVT = VT.getVectorElementType();
+    unsigned SVTBits = SVT.getSizeInBits();
+
+    ConstantSDNode *CND = cast<ConstantSDNode>(Op1);
+    const APInt &C = APInt(SVTBits, CND->getAPIntValue().getZExtValue());
+    uint64_t ShAmt = C.getZExtValue();
+
+    // Don't try to convert this shift into a ISD::SRA if the shift
+    // count is bigger than or equal to the element size.
+    if (ShAmt >= SVTBits)
+      return SDValue();
+
+    // Trivial case: if the shift count is zero, then fold this
+    // into the first operand.
+    if (ShAmt == 0)
+      return Op0;
+
+    // Replace this packed shift intrinsic with a target independent
+    // shift dag node.
+    SDValue Splat = DAG.getConstant(C, VT);
+    return DAG.getNode(ISD::SRA, SDLoc(N), VT, Op0, Splat);
+  }
+  }
+}
+
 /// PerformMulCombine - Optimize a single multiply with constant into two
 /// in order to implement it with two cheaper instructions, e.g.
 /// LEA + SHL, LEA + LEA.
@@ -20304,6 +20358,7 @@ SDValue X86TargetLowering::PerformDAGCombine(SDNode *N,
   case X86ISD::VPERM2X128:
   case ISD::VECTOR_SHUFFLE: return PerformShuffleCombine(N, DAG, DCI,Subtarget);
   case ISD::FMA:            return PerformFMACombine(N, DAG, Subtarget);
+  case ISD::INTRINSIC_WO_CHAIN: return PerformINTRINSIC_WO_CHAINCombine(N, DAG);
   }
 
   return SDValue();
diff --git a/llvm/test/CodeGen/X86/combine-avx2-intrinsics.ll b/llvm/test/CodeGen/X86/combine-avx2-intrinsics.ll
new file mode 100644
index 000000000000..0560a8d6ae25
--- /dev/null
+++ b/llvm/test/CodeGen/X86/combine-avx2-intrinsics.ll
@@ -0,0 +1,51 @@
+; RUN: llc < %s -march=x86-64 -mcpu=core-avx2 | FileCheck %s
+
+; Verify that the backend correctly combines AVX2 builtin intrinsics.
+
+
+define <8 x i32> @test_psra_1(<8 x i32> %A) {
+  %1 = tail call <8 x i32> @llvm.x86.avx2.psrai.d(<8 x i32> %A, i32 3)
+  %2 = tail call <8 x i32> @llvm.x86.avx2.psra.d(<8 x i32> %1, <4 x i32> <i32 3, i32 0, i32 7, i32 0>)
+  %3 = tail call <8 x i32> @llvm.x86.avx2.psrai.d(<8 x i32> %2, i32 2)
+  ret <8 x i32> %3
+}
+; CHECK-LABEL: test_psra_1
+; CHECK: vpsrad $8, %ymm0, %ymm0
+; CHECK-NEXT: ret
+
+define <16 x i16> @test_psra_2(<16 x i16> %A) {
+  %1 = tail call <16 x i16> @llvm.x86.avx2.psrai.w(<16 x i16> %A, i32 3)
+  %2 = tail call <16 x i16> @llvm.x86.avx2.psra.w(<16 x i16> %1, <8 x i16> <i16 3, i16 0, i16 0, i16 0, i16 7, i16 0, i16 0, i16 0>)
+  %3 = tail call <16 x i16> @llvm.x86.avx2.psrai.w(<16 x i16> %2, i32 2)
+  ret <16 x i16> %3
+}
+; CHECK-LABEL: test_psra_2
+; CHECK: vpsraw $8, %ymm0, %ymm0
+; CHECK-NEXT: ret
+
+define <16 x i16> @test_psra_3(<16 x i16> %A) {
+  %1 = tail call <16 x i16> @llvm.x86.avx2.psrai.w(<16 x i16> %A, i32 0)
+  %2 = tail call <16 x i16> @llvm.x86.avx2.psra.w(<16 x i16> %1, <8 x i16> <i16 0, i16 0, i16 0, i16 0, i16 7, i16 0, i16 0, i16 0>)
+  %3 = tail call <16 x i16> @llvm.x86.avx2.psrai.w(<16 x i16> %2, i32 0)
+  ret <16 x i16> %3
+}
+; CHECK-LABEL: test_psra_3
+; CHECK-NOT: vpsraw
+; CHECK: ret
+
+define <8 x i32> @test_psra_4(<8 x i32> %A) {
+  %1 = tail call <8 x i32> @llvm.x86.avx2.psrai.d(<8 x i32> %A, i32 0)
+  %2 = tail call <8 x i32> @llvm.x86.avx2.psra.d(<8 x i32> %1, <4 x i32> <i32 0, i32 0, i32 7, i32 0>)
+  %3 = tail call <8 x i32> @llvm.x86.avx2.psrai.d(<8 x i32> %2, i32 0)
+  ret <8 x i32> %3
+}
+; CHECK-LABEL: test_psra_4
+; CHECK-NOT: vpsrad
+; CHECK: ret
+
+
+declare <16 x i16> @llvm.x86.avx2.psra.w(<16 x i16>, <8 x i16>)
+declare <16 x i16> @llvm.x86.avx2.psrai.w(<16 x i16>, i32)
+declare <8 x i32> @llvm.x86.avx2.psra.d(<8 x i32>, <4 x i32>)
+declare <8 x i32> @llvm.x86.avx2.psrai.d(<8 x i32>, i32)
+
diff --git a/llvm/test/CodeGen/X86/combine-sse2-intrinsics.ll b/llvm/test/CodeGen/X86/combine-sse2-intrinsics.ll
new file mode 100644
index 000000000000..fa500e5d8d67
--- /dev/null
+++ b/llvm/test/CodeGen/X86/combine-sse2-intrinsics.ll
@@ -0,0 +1,53 @@
+; RUN: llc < %s -march=x86 -mcpu=core2 | FileCheck %s
+; RUN: llc < %s -march=x86-64 -mcpu=corei7 | FileCheck %s
+
+; Verify that the backend correctly combines SSE2 builtin intrinsics.
+
+
+define <4 x i32> @test_psra_1(<4 x i32> %A) {
+  %1 = tail call <4 x i32> @llvm.x86.sse2.psrai.d(<4 x i32> %A, i32 3)
+  %2 = tail call <4 x i32> @llvm.x86.sse2.psra.d(<4 x i32> %1, <4 x i32> <i32 3, i32 0, i32 7, i32 0>)
+  %3 = tail call <4 x i32> @llvm.x86.sse2.psrai.d(<4 x i32> %2, i32 2)
+  ret <4 x i32> %3
+}
+; CHECK-LABEL: test_psra_1
+; CHECK: psrad $8, %xmm0
+; CHECK-NEXT: ret
+
+define <8 x i16> @test_psra_2(<8 x i16> %A) {
+  %1 = tail call <8 x i16> @llvm.x86.sse2.psrai.w(<8 x i16> %A, i32 3)
+  %2 = tail call <8 x i16> @llvm.x86.sse2.psra.w(<8 x i16> %1, <8 x i16> <i16 3, i16 0, i16 0, i16 0, i16 7, i16 0, i16 0, i16 0>)
+  %3 = tail call <8 x i16> @llvm.x86.sse2.psrai.w(<8 x i16> %2, i32 2)
+  ret <8 x i16> %3
+}
+; CHECK-LABEL: test_psra_2
+; CHECK: psraw $8, %xmm0
+; CHECK-NEXT: ret
+
+define <4 x i32> @test_psra_3(<4 x i32> %A) {
+  %1 = tail call <4 x i32> @llvm.x86.sse2.psrai.d(<4 x i32> %A, i32 0)
+  %2 = tail call <4 x i32> @llvm.x86.sse2.psra.d(<4 x i32> %1, <4 x i32> <i32 0, i32 0, i32 7, i32 0>)
+  %3 = tail call <4 x i32> @llvm.x86.sse2.psrai.d(<4 x i32> %2, i32 0)
+  ret <4 x i32> %3
+}
+; CHECK-LABEL: test_psra_3
+; CHECK-NOT: psrad
+; CHECK: ret
+
+
+define <8 x i16> @test_psra_4(<8 x i16> %A) {
+  %1 = tail call <8 x i16> @llvm.x86.sse2.psrai.w(<8 x i16> %A, i32 0)
+  %2 = tail call <8 x i16> @llvm.x86.sse2.psra.w(<8 x i16> %1, <8 x i16> <i16 0, i16 0, i16 0, i16 0, i16 7, i16 0, i16 0, i16 0>)
+  %3 = tail call <8 x i16> @llvm.x86.sse2.psrai.w(<8 x i16> %2, i32 0)
+  ret <8 x i16> %3
+}
+; CHECK-LABEL: test_psra_4
+; CHECK-NOT: psraw
+; CHECK: ret
+
+
+declare <8 x i16> @llvm.x86.sse2.psra.w(<8 x i16>, <8 x i16>)
+declare <8 x i16> @llvm.x86.sse2.psrai.w(<8 x i16>, i32)
+declare <4 x i32> @llvm.x86.sse2.psra.d(<4 x i32>, <4 x i32>)
+declare <4 x i32> @llvm.x86.sse2.psrai.d(<4 x i32>, i32)
+