Index: lib/Target/X86/X86ISelLowering.cpp
===================================================================
--- lib/Target/X86/X86ISelLowering.cpp
+++ lib/Target/X86/X86ISelLowering.cpp
@@ -7359,16 +7359,36 @@
                                          SDValue V2, ArrayRef<int> Mask,
                                          const X86Subtarget *Subtarget,
                                          SelectionDAG &DAG) {
+  // Determine if inputs are safe splats (no undefs).
+  auto isSafeSplat = [](SDValue V) {
+    BitVector UndefElements;
+    if (auto *BVOp = dyn_cast<BuildVectorSDNode>(V.getNode())) {
+      if (BVOp->getConstantSplatNode(&UndefElements) && UndefElements.none())
+        return true;
+      if (BVOp->getConstantFPSplatNode(&UndefElements) && UndefElements.none())
+        return true;
+    }
+    if (auto *SVNOp = dyn_cast<ShuffleVectorSDNode>(V.getNode())) {
+      ArrayRef<int> SVNMask = SVNOp->getMask();
+      for (int i = 0, Size = SVNMask.size(); i < Size; ++i)
+        if (SVNMask[i] < 0 || SVNMask[i] != SVNMask[0])
+          return false;
+      return true;
+    }
+    return false;
+  };
+  bool IsV1Splat = isSafeSplat(V1);
+  bool IsV2Splat = isSafeSplat(V2);
 
   unsigned BlendMask = 0;
   for (int i = 0, Size = Mask.size(); i < Size; ++i) {
     if (Mask[i] >= Size) {
-      if (Mask[i] != i + Size)
+      if (Mask[i] != i + Size && !IsV2Splat)
         return SDValue(); // Shuffled V2 input!
       BlendMask |= 1u << i;
       continue;
     }
-    if (Mask[i] >= 0 && Mask[i] != i)
+    if (Mask[i] >= 0 && Mask[i] != i && !IsV1Splat)
       return SDValue(); // Shuffled V1 input!
   }
   switch (VT.SimpleTy) {
Index: test/CodeGen/X86/combine-or.ll
===================================================================
--- test/CodeGen/X86/combine-or.ll
+++ test/CodeGen/X86/combine-or.ll
@@ -206,10 +206,10 @@
 define <4 x i32> @test17(<4 x i32> %a, <4 x i32> %b) {
 ; CHECK-LABEL: test17:
 ; CHECK:       # BB#0:
-; CHECK-NEXT:    xorps %xmm2, %xmm2
-; CHECK-NEXT:    shufps {{.*#+}} xmm1 = xmm1[0,1],xmm2[0,0]
-; CHECK-NEXT:    shufps {{.*#+}} xmm2 = xmm2[0,0],xmm0[0,2]
-; CHECK-NEXT:    shufps {{.*#+}} xmm2 = xmm2[0,2,1,3]
+; CHECK-NEXT:    pxor %xmm2, %xmm2
+; CHECK-NEXT:    pblendw {{.*#+}} xmm1 = xmm1[0,1,2,3],xmm2[4,5,6,7]
+; CHECK-NEXT:    shufps	{{.*#+}} xmm2 = xmm2[0,0],xmm0[0,2]
+; CHECK-NEXT:    shufps	{{.*#+}} xmm2 = xmm2[0,2,1,3]
 ; CHECK-NEXT:    orps %xmm1, %xmm2
 ; CHECK-NEXT:    movaps %xmm2, %xmm0
 ; CHECK-NEXT:    retq
Index: test/CodeGen/X86/vector-blend.ll
===================================================================
--- test/CodeGen/X86/vector-blend.ll
+++ test/CodeGen/X86/vector-blend.ll
@@ -799,3 +799,46 @@
   %select = shufflevector <4 x i64> %a, <4 x i64> %b, <4 x i32> <i32 4, i32 1, i32 6, i32 7>
   ret <4 x i64> %select
 }
+
+; Blend with Splat
+
+define <4 x float> @blend_splat_float(<4 x float> %v1, <4 x float> %v2) {
+; SSE2-LABEL: blend_splat_float:
+; SSE2:       # BB#0: # %entry
+; SSE2-NEXT:    shufps {{.*#+}} xmm1 = xmm1[3,3,3,3]
+; SSE2-NEXT:    shufps {{.*#+}} xmm1 = xmm1[0,3],xmm0[1,3]
+; SSE2-NEXT:    shufps {{.*#+}} xmm1 = xmm1[0,2,1,3]
+; SSE2-NEXT:    movaps	%xmm1, %xmm0
+; SSE2-NEXT:    retq
+;
+; SSSE3-LABEL: blend_splat_float:
+; SSSE3:       # BB#0: # %entry
+; SSSE3-NEXT:    shufps {{.*#+}} xmm1 = xmm1[3,3,3,3]
+; SSSE3-NEXT:    shufps {{.*#+}} xmm1 = xmm1[0,3],xmm0[1,3]
+; SSSE3-NEXT:    shufps {{.*#+}} xmm1 = xmm1[0,2,1,3]
+; SSSE3-NEXT:    movaps	%xmm1, %xmm0
+; SSSE3-NEXT:    retq
+;
+; SSE41-LABEL: blend_splat_float:
+; SSE41:       # BB#0: # %entry
+; SSE41-NEXT:    shufps {{.*#+}} xmm1 = xmm1[3,3,3,3]
+; SSE41-NEXT:    blendps {{.*#+}} xmm0 = xmm1[0],xmm0[1],xmm1[2],xmm0[3]
+; SSE41-NEXT:    retq
+;
+; AVX1-LABEL: blend_splat_float:
+; AVX1:       # BB#0: # %entry
+; AVX1-NEXT:    vpermilps {{.*#+}} xmm1 = xmm1[3,3,3,3]
+; AVX1-NEXT:    vblendps {{.*#+}} xmm0 = xmm1[0],xmm0[1],xmm1[2],xmm0[3]
+; AVX1-NEXT:    retq
+;
+; AVX2-LABEL: blend_splat_float:
+; AVX2:       # BB#0: # %entry
+; AVX2-NEXT:    vpermilps {{.*#+}} xmm1 = xmm1[3,3,3,3]
+; AVX2-NEXT:    vblendps {{.*#+}} xmm0 = xmm1[0],xmm0[1],xmm1[2],xmm0[3]
+; AVX2-NEXT:    retq
+entry:
+  %splat = shufflevector <4 x float> %v2, <4 x float> undef, <4 x i32> <i32 3, i32 3, i32 3, i32 3>
+  %select = shufflevector <4 x float> %v1, <4 x float> %splat, <4 x i32> <i32 4, i32 1, i32 7, i32 3>
+  ret <4 x float> %select
+}
+