diff --git a/llvm/lib/CodeGen/SelectionDAG/TargetLowering.cpp b/llvm/lib/CodeGen/SelectionDAG/TargetLowering.cpp
--- a/llvm/lib/CodeGen/SelectionDAG/TargetLowering.cpp
+++ b/llvm/lib/CodeGen/SelectionDAG/TargetLowering.cpp
@@ -819,13 +819,21 @@
     break;
   }
   case ISD::INSERT_SUBVECTOR: {
-    // If we don't demand the inserted subvector, return the base vector.
     SDValue Vec = Op.getOperand(0);
     SDValue Sub = Op.getOperand(1);
     uint64_t Idx = Op.getConstantOperandVal(2);
     unsigned NumSubElts = Sub.getValueType().getVectorNumElements();
-    if (DemandedElts.extractBits(NumSubElts, Idx) == 0)
+    APInt DemandedSubElts = DemandedElts.extractBits(NumSubElts, Idx);
+    // If we don't demand the inserted subvector, return the base vector.
+    if (DemandedSubElts == 0)
       return Vec;
+    // If this simply widens the lowest subvector, see if we can do it earlier.
+    if (Idx == 0 && Vec.isUndef()) {
+      if (SDValue NewSub = SimplifyMultipleUseDemandedBits(
+              Sub, DemandedBits, DemandedSubElts, DAG, Depth + 1))
+        return DAG.getNode(Op.getOpcode(), SDLoc(Op), Op.getValueType(),
+                           Op.getOperand(0), NewSub, Op.getOperand(2));
+    }
     break;
   }
   case ISD::VECTOR_SHUFFLE: {
diff --git a/llvm/test/CodeGen/AArch64/vecreduce-and-legalization.ll b/llvm/test/CodeGen/AArch64/vecreduce-and-legalization.ll
--- a/llvm/test/CodeGen/AArch64/vecreduce-and-legalization.ll
+++ b/llvm/test/CodeGen/AArch64/vecreduce-and-legalization.ll
@@ -113,7 +113,7 @@
 ; CHECK-NEXT:    and w8, w8, w9
 ; CHECK-NEXT:    umov w9, v0.b[4]
 ; CHECK-NEXT:    and w8, w8, w9
-; CHECK-NEXT:    umov w9, v1.b[5]
+; CHECK-NEXT:    umov w9, v0.b[5]
 ; CHECK-NEXT:    and w8, w8, w9
 ; CHECK-NEXT:    umov w9, v0.b[6]
 ; CHECK-NEXT:    and w8, w8, w9
diff --git a/llvm/test/CodeGen/X86/avg.ll b/llvm/test/CodeGen/X86/avg.ll
--- a/llvm/test/CodeGen/X86/avg.ll
+++ b/llvm/test/CodeGen/X86/avg.ll
@@ -2265,25 +2265,25 @@
 ; AVX512-NEXT:    vpmovzxbw {{.*#+}} ymm0 = mem[0],zero,mem[1],zero,mem[2],zero,mem[3],zero,mem[4],zero,mem[5],zero,mem[6],zero,mem[7],zero,mem[8],zero,mem[9],zero,mem[10],zero,mem[11],zero,mem[12],zero,mem[13],zero,mem[14],zero,mem[15],zero
 ; AVX512-NEXT:    vpmovzxwd {{.*#+}} ymm2 = xmm1[0],zero,xmm1[1],zero,xmm1[2],zero,xmm1[3],zero,xmm1[4],zero,xmm1[5],zero,xmm1[6],zero,xmm1[7],zero
 ; AVX512-NEXT:    vpmovzxdq {{.*#+}} ymm3 = xmm2[0],zero,xmm2[1],zero,xmm2[2],zero,xmm2[3],zero
-; AVX512-NEXT:    vmovq %xmm3, %rbx
-; AVX512-NEXT:    vpextrq $1, %xmm3, %rbp
-; AVX512-NEXT:    vextracti128 $1, %ymm3, %xmm3
+; AVX512-NEXT:    vextracti128 $1, %ymm3, %xmm4
+; AVX512-NEXT:    vmovq %xmm4, %rbx
+; AVX512-NEXT:    vpextrq $1, %xmm4, %rbp
 ; AVX512-NEXT:    vmovq %xmm3, %rdi
 ; AVX512-NEXT:    vpextrq $1, %xmm3, %rsi
 ; AVX512-NEXT:    vextracti128 $1, %ymm2, %xmm2
 ; AVX512-NEXT:    vpmovzxdq {{.*#+}} ymm2 = xmm2[0],zero,xmm2[1],zero,xmm2[2],zero,xmm2[3],zero
 ; AVX512-NEXT:    vmovq %xmm2, %rdx
-; AVX512-NEXT:    vpextrq $1, %xmm2, %r15
+; AVX512-NEXT:    vpextrq $1, %xmm2, %r10
 ; AVX512-NEXT:    vextracti128 $1, %ymm2, %xmm2
-; AVX512-NEXT:    vmovq %xmm2, %r8
-; AVX512-NEXT:    vpextrq $1, %xmm2, %r9
+; AVX512-NEXT:    vmovq %xmm2, %r13
+; AVX512-NEXT:    vpextrq $1, %xmm2, %r14
 ; AVX512-NEXT:    vextracti128 $1, %ymm1, %xmm1
 ; AVX512-NEXT:    vpmovzxwd {{.*#+}} ymm1 = xmm1[0],zero,xmm1[1],zero,xmm1[2],zero,xmm1[3],zero,xmm1[4],zero,xmm1[5],zero,xmm1[6],zero,xmm1[7],zero
 ; AVX512-NEXT:    vpmovzxdq {{.*#+}} ymm2 = xmm1[0],zero,xmm1[1],zero,xmm1[2],zero,xmm1[3],zero
-; AVX512-NEXT:    vmovq %xmm2, %r11
-; AVX512-NEXT:    vpextrq $1, %xmm2, %r10
+; AVX512-NEXT:    vmovq %xmm2, %r15
+; AVX512-NEXT:    vpextrq $1, %xmm2, %r8
 ; AVX512-NEXT:    vextracti128 $1, %ymm2, %xmm2
-; AVX512-NEXT:    vmovq %xmm2, {{[-0-9]+}}(%r{{[sb]}}p) # 8-byte Folded Spill
+; AVX512-NEXT:    vmovq %xmm2, %r11
 ; AVX512-NEXT:    vpextrq $1, %xmm2, {{[-0-9]+}}(%r{{[sb]}}p) # 8-byte Folded Spill
 ; AVX512-NEXT:    vextracti128 $1, %ymm1, %xmm1
 ; AVX512-NEXT:    vpmovzxdq {{.*#+}} ymm1 = xmm1[0],zero,xmm1[1],zero,xmm1[2],zero,xmm1[3],zero
@@ -2292,83 +2292,85 @@
 ; AVX512-NEXT:    vextracti128 $1, %ymm1, %xmm1
 ; AVX512-NEXT:    vpmovzxwd {{.*#+}} ymm2 = xmm0[0],zero,xmm0[1],zero,xmm0[2],zero,xmm0[3],zero,xmm0[4],zero,xmm0[5],zero,xmm0[6],zero,xmm0[7],zero
 ; AVX512-NEXT:    vpmovzxdq {{.*#+}} ymm3 = xmm2[0],zero,xmm2[1],zero,xmm2[2],zero,xmm2[3],zero
-; AVX512-NEXT:    vmovq %xmm3, %rcx
-; AVX512-NEXT:    addq %rbx, %rcx
-; AVX512-NEXT:    vpextrq $1, %xmm3, %rax
+; AVX512-NEXT:    vextracti128 $1, %ymm3, %xmm4
+; AVX512-NEXT:    vmovq %xmm4, %rax
+; AVX512-NEXT:    addq %rbx, %rax
+; AVX512-NEXT:    movq %rax, %rbx
+; AVX512-NEXT:    vpextrq $1, %xmm4, %rax
 ; AVX512-NEXT:    addq %rbp, %rax
-; AVX512-NEXT:    movq %rax, %rbp
-; AVX512-NEXT:    vextracti128 $1, %ymm3, %xmm3
-; AVX512-NEXT:    vmovq %xmm3, %r14
-; AVX512-NEXT:    addq %rdi, %r14
+; AVX512-NEXT:    movq %rax, %r9
+; AVX512-NEXT:    vmovq %xmm3, %rcx
+; AVX512-NEXT:    addq %rdi, %rcx
 ; AVX512-NEXT:    vpextrq $1, %xmm3, %rax
 ; AVX512-NEXT:    addq %rsi, %rax
 ; AVX512-NEXT:    movq %rax, {{[-0-9]+}}(%r{{[sb]}}p) # 8-byte Spill
 ; AVX512-NEXT:    vextracti128 $1, %ymm2, %xmm2
 ; AVX512-NEXT:    vpmovzxdq {{.*#+}} ymm2 = xmm2[0],zero,xmm2[1],zero,xmm2[2],zero,xmm2[3],zero
-; AVX512-NEXT:    vmovq %xmm2, %rax
-; AVX512-NEXT:    addq %rdx, %rax
-; AVX512-NEXT:    movq %rax, %rdx
-; AVX512-NEXT:    vpextrq $1, %xmm2, %r12
-; AVX512-NEXT:    addq %r15, %r12
+; AVX512-NEXT:    vmovq %xmm2, %rbp
+; AVX512-NEXT:    addq %rdx, %rbp
+; AVX512-NEXT:    vpextrq $1, %xmm2, %rax
+; AVX512-NEXT:    addq %r10, %rax
+; AVX512-NEXT:    movq %rax, {{[-0-9]+}}(%r{{[sb]}}p) # 8-byte Spill
 ; AVX512-NEXT:    vextracti128 $1, %ymm2, %xmm2
 ; AVX512-NEXT:    vmovq %xmm2, %rax
-; AVX512-NEXT:    addq %r8, %rax
-; AVX512-NEXT:    movq %rax, {{[-0-9]+}}(%r{{[sb]}}p) # 8-byte Spill
+; AVX512-NEXT:    addq %r13, %rax
+; AVX512-NEXT:    movq %rax, %r13
 ; AVX512-NEXT:    vpextrq $1, %xmm2, %rax
-; AVX512-NEXT:    addq %r9, %rax
+; AVX512-NEXT:    addq %r14, %rax
 ; AVX512-NEXT:    movq %rax, {{[-0-9]+}}(%r{{[sb]}}p) # 8-byte Spill
 ; AVX512-NEXT:    vextracti128 $1, %ymm0, %xmm0
 ; AVX512-NEXT:    vpmovzxwd {{.*#+}} ymm0 = xmm0[0],zero,xmm0[1],zero,xmm0[2],zero,xmm0[3],zero,xmm0[4],zero,xmm0[5],zero,xmm0[6],zero,xmm0[7],zero
 ; AVX512-NEXT:    vpmovzxdq {{.*#+}} ymm2 = xmm0[0],zero,xmm0[1],zero,xmm0[2],zero,xmm0[3],zero
 ; AVX512-NEXT:    vmovq %xmm2, %rax
-; AVX512-NEXT:    addq %r11, %rax
+; AVX512-NEXT:    addq %r15, %rax
 ; AVX512-NEXT:    movq %rax, {{[-0-9]+}}(%r{{[sb]}}p) # 8-byte Spill
 ; AVX512-NEXT:    vpextrq $1, %xmm2, %rax
-; AVX512-NEXT:    addq %r10, %rax
+; AVX512-NEXT:    addq %r8, %rax
 ; AVX512-NEXT:    movq %rax, {{[-0-9]+}}(%r{{[sb]}}p) # 8-byte Spill
 ; AVX512-NEXT:    vextracti128 $1, %ymm2, %xmm2
-; AVX512-NEXT:    vmovq %xmm2, %r13
-; AVX512-NEXT:    addq {{[-0-9]+}}(%r{{[sb]}}p), %r13 # 8-byte Folded Reload
-; AVX512-NEXT:    vpextrq $1, %xmm2, %rbx
-; AVX512-NEXT:    addq {{[-0-9]+}}(%r{{[sb]}}p), %rbx # 8-byte Folded Reload
+; AVX512-NEXT:    vmovq %xmm2, %rax
+; AVX512-NEXT:    addq %r11, %rax
+; AVX512-NEXT:    movq %rax, {{[-0-9]+}}(%r{{[sb]}}p) # 8-byte Spill
+; AVX512-NEXT:    vpextrq $1, %xmm2, %r12
+; AVX512-NEXT:    addq {{[-0-9]+}}(%r{{[sb]}}p), %r12 # 8-byte Folded Reload
 ; AVX512-NEXT:    vextracti128 $1, %ymm0, %xmm0
 ; AVX512-NEXT:    vpmovzxdq {{.*#+}} ymm0 = xmm0[0],zero,xmm0[1],zero,xmm0[2],zero,xmm0[3],zero
-; AVX512-NEXT:    vmovq %xmm0, %r10
-; AVX512-NEXT:    addq {{[-0-9]+}}(%r{{[sb]}}p), %r10 # 8-byte Folded Reload
-; AVX512-NEXT:    vpextrq $1, %xmm0, %r9
-; AVX512-NEXT:    addq {{[-0-9]+}}(%r{{[sb]}}p), %r9 # 8-byte Folded Reload
+; AVX512-NEXT:    vmovq %xmm0, %r11
+; AVX512-NEXT:    addq {{[-0-9]+}}(%r{{[sb]}}p), %r11 # 8-byte Folded Reload
+; AVX512-NEXT:    vpextrq $1, %xmm0, %r8
+; AVX512-NEXT:    addq {{[-0-9]+}}(%r{{[sb]}}p), %r8 # 8-byte Folded Reload
 ; AVX512-NEXT:    vmovq %xmm1, %rax
 ; AVX512-NEXT:    vextracti128 $1, %ymm0, %xmm0
-; AVX512-NEXT:    vmovq %xmm0, %r8
-; AVX512-NEXT:    addq %rax, %r8
-; AVX512-NEXT:    vpextrq $1, %xmm1, %rdi
-; AVX512-NEXT:    vpextrq $1, %xmm0, %rsi
-; AVX512-NEXT:    addq %rdi, %rsi
-; AVX512-NEXT:    addq $-1, %rcx
-; AVX512-NEXT:    movq %rcx, {{[-0-9]+}}(%r{{[sb]}}p) # 8-byte Spill
-; AVX512-NEXT:    movl $0, %r11d
-; AVX512-NEXT:    adcq $-1, %r11
-; AVX512-NEXT:    addq $-1, %rbp
-; AVX512-NEXT:    movq %rbp, {{[-0-9]+}}(%r{{[sb]}}p) # 8-byte Spill
-; AVX512-NEXT:    movl $0, %edi
-; AVX512-NEXT:    adcq $-1, %rdi
-; AVX512-NEXT:    addq $-1, %r14
-; AVX512-NEXT:    movq %r14, {{[-0-9]+}}(%r{{[sb]}}p) # 8-byte Spill
+; AVX512-NEXT:    vmovq %xmm0, %rdi
+; AVX512-NEXT:    addq %rax, %rdi
+; AVX512-NEXT:    vpextrq $1, %xmm1, %rsi
+; AVX512-NEXT:    vpextrq $1, %xmm0, %rdx
+; AVX512-NEXT:    addq %rsi, %rdx
+; AVX512-NEXT:    addq $-1, %rbx
+; AVX512-NEXT:    movq %rbx, {{[-0-9]+}}(%r{{[sb]}}p) # 8-byte Spill
 ; AVX512-NEXT:    movl $0, %r15d
 ; AVX512-NEXT:    adcq $-1, %r15
-; AVX512-NEXT:    addq $-1, {{[-0-9]+}}(%r{{[sb]}}p) # 8-byte Folded Spill
+; AVX512-NEXT:    addq $-1, %r9
+; AVX512-NEXT:    movq %r9, {{[-0-9]+}}(%r{{[sb]}}p) # 8-byte Spill
 ; AVX512-NEXT:    movl $0, %r14d
 ; AVX512-NEXT:    adcq $-1, %r14
-; AVX512-NEXT:    addq $-1, %rdx
-; AVX512-NEXT:    movq %rdx, {{[-0-9]+}}(%r{{[sb]}}p) # 8-byte Spill
+; AVX512-NEXT:    addq $-1, %rcx
+; AVX512-NEXT:    movq %rcx, {{[-0-9]+}}(%r{{[sb]}}p) # 8-byte Spill
+; AVX512-NEXT:    movl $0, %esi
+; AVX512-NEXT:    adcq $-1, %rsi
+; AVX512-NEXT:    addq $-1, {{[-0-9]+}}(%r{{[sb]}}p) # 8-byte Folded Spill
+; AVX512-NEXT:    movl $0, %r10d
+; AVX512-NEXT:    adcq $-1, %r10
+; AVX512-NEXT:    addq $-1, %rbp
+; AVX512-NEXT:    movq %rbp, (%rsp) # 8-byte Spill
+; AVX512-NEXT:    movl $0, %r9d
+; AVX512-NEXT:    adcq $-1, %r9
+; AVX512-NEXT:    addq $-1, {{[-0-9]+}}(%r{{[sb]}}p) # 8-byte Folded Spill
 ; AVX512-NEXT:    movl $0, %eax
 ; AVX512-NEXT:    adcq $-1, %rax
-; AVX512-NEXT:    movq %rax, (%rsp) # 8-byte Spill
-; AVX512-NEXT:    addq $-1, %r12
-; AVX512-NEXT:    movq %r12, {{[-0-9]+}}(%r{{[sb]}}p) # 8-byte Spill
-; AVX512-NEXT:    movl $0, %r12d
-; AVX512-NEXT:    adcq $-1, %r12
-; AVX512-NEXT:    addq $-1, {{[-0-9]+}}(%r{{[sb]}}p) # 8-byte Folded Spill
+; AVX512-NEXT:    movq %rax, {{[-0-9]+}}(%r{{[sb]}}p) # 8-byte Spill
+; AVX512-NEXT:    addq $-1, %r13
+; AVX512-NEXT:    movq %r13, {{[-0-9]+}}(%r{{[sb]}}p) # 8-byte Spill
 ; AVX512-NEXT:    movl $0, %eax
 ; AVX512-NEXT:    adcq $-1, %rax
 ; AVX512-NEXT:    movq %rax, {{[-0-9]+}}(%r{{[sb]}}p) # 8-byte Spill
@@ -2384,89 +2386,89 @@
 ; AVX512-NEXT:    movl $0, %eax
 ; AVX512-NEXT:    adcq $-1, %rax
 ; AVX512-NEXT:    movq %rax, {{[-0-9]+}}(%r{{[sb]}}p) # 8-byte Spill
-; AVX512-NEXT:    addq $-1, %r13
+; AVX512-NEXT:    movq {{[-0-9]+}}(%r{{[sb]}}p), %rcx # 8-byte Reload
+; AVX512-NEXT:    addq $-1, %rcx
 ; AVX512-NEXT:    movl $0, %eax
 ; AVX512-NEXT:    adcq $-1, %rax
 ; AVX512-NEXT:    movq %rax, {{[-0-9]+}}(%r{{[sb]}}p) # 8-byte Spill
-; AVX512-NEXT:    addq $-1, %rbx
+; AVX512-NEXT:    addq $-1, %r12
 ; AVX512-NEXT:    movl $0, %eax
 ; AVX512-NEXT:    adcq $-1, %rax
 ; AVX512-NEXT:    movq %rax, {{[-0-9]+}}(%r{{[sb]}}p) # 8-byte Spill
-; AVX512-NEXT:    addq $-1, %r10
-; AVX512-NEXT:    movl $0, %edx
-; AVX512-NEXT:    adcq $-1, %rdx
-; AVX512-NEXT:    addq $-1, %r9
-; AVX512-NEXT:    movl $0, %ecx
-; AVX512-NEXT:    adcq $-1, %rcx
+; AVX512-NEXT:    addq $-1, %r11
+; AVX512-NEXT:    movl $0, %r13d
+; AVX512-NEXT:    adcq $-1, %r13
 ; AVX512-NEXT:    addq $-1, %r8
 ; AVX512-NEXT:    movl $0, %eax
 ; AVX512-NEXT:    adcq $-1, %rax
-; AVX512-NEXT:    addq $-1, %rsi
+; AVX512-NEXT:    addq $-1, %rdi
+; AVX512-NEXT:    movl $0, %ebx
+; AVX512-NEXT:    adcq $-1, %rbx
+; AVX512-NEXT:    addq $-1, %rdx
 ; AVX512-NEXT:    movl $0, %ebp
 ; AVX512-NEXT:    adcq $-1, %rbp
-; AVX512-NEXT:    shldq $63, %rsi, %rbp
+; AVX512-NEXT:    shldq $63, %rdx, %rbp
 ; AVX512-NEXT:    movq %rbp, {{[-0-9]+}}(%r{{[sb]}}p) # 8-byte Spill
+; AVX512-NEXT:    shldq $63, %rdi, %rbx
+; AVX512-NEXT:    movq %rbx, {{[-0-9]+}}(%r{{[sb]}}p) # 8-byte Spill
 ; AVX512-NEXT:    shldq $63, %r8, %rax
-; AVX512-NEXT:    movq %rax, {{[-0-9]+}}(%r{{[sb]}}p) # 8-byte Spill
-; AVX512-NEXT:    shldq $63, %r9, %rcx
-; AVX512-NEXT:    movq %rcx, %rbp
-; AVX512-NEXT:    shldq $63, %r10, %rdx
-; AVX512-NEXT:    movq %rdx, %r9
-; AVX512-NEXT:    movq {{[-0-9]+}}(%r{{[sb]}}p), %r10 # 8-byte Reload
-; AVX512-NEXT:    shldq $63, %rbx, %r10
-; AVX512-NEXT:    movq {{[-0-9]+}}(%r{{[sb]}}p), %r8 # 8-byte Reload
-; AVX512-NEXT:    shldq $63, %r13, %r8
+; AVX512-NEXT:    movq %rax, %r8
+; AVX512-NEXT:    shldq $63, %r11, %r13
+; AVX512-NEXT:    movq {{[-0-9]+}}(%r{{[sb]}}p), %r11 # 8-byte Reload
+; AVX512-NEXT:    shldq $63, %r12, %r11
+; AVX512-NEXT:    movq {{[-0-9]+}}(%r{{[sb]}}p), %r12 # 8-byte Reload
+; AVX512-NEXT:    shldq $63, %rcx, %r12
+; AVX512-NEXT:    movq {{[-0-9]+}}(%r{{[sb]}}p), %rbp # 8-byte Reload
 ; AVX512-NEXT:    movq {{[-0-9]+}}(%r{{[sb]}}p), %rax # 8-byte Reload
-; AVX512-NEXT:    movq {{[-0-9]+}}(%r{{[sb]}}p), %r13 # 8-byte Reload
-; AVX512-NEXT:    shldq $63, %rax, %r13
+; AVX512-NEXT:    shldq $63, %rax, %rbp
 ; AVX512-NEXT:    movq {{[-0-9]+}}(%r{{[sb]}}p), %rax # 8-byte Reload
 ; AVX512-NEXT:    movq {{[-0-9]+}}(%r{{[sb]}}p), %rbx # 8-byte Reload
 ; AVX512-NEXT:    shldq $63, %rax, %rbx
 ; AVX512-NEXT:    movq {{[-0-9]+}}(%r{{[sb]}}p), %rax # 8-byte Reload
-; AVX512-NEXT:    movq {{[-0-9]+}}(%r{{[sb]}}p), %rsi # 8-byte Reload
-; AVX512-NEXT:    shldq $63, %rax, %rsi
-; AVX512-NEXT:    movq {{[-0-9]+}}(%r{{[sb]}}p), %rax # 8-byte Reload
+; AVX512-NEXT:    movq {{[-0-9]+}}(%r{{[sb]}}p), %rdi # 8-byte Reload
+; AVX512-NEXT:    shldq $63, %rax, %rdi
 ; AVX512-NEXT:    movq {{[-0-9]+}}(%r{{[sb]}}p), %rdx # 8-byte Reload
-; AVX512-NEXT:    shldq $63, %rax, %rdx
 ; AVX512-NEXT:    movq {{[-0-9]+}}(%r{{[sb]}}p), %rax # 8-byte Reload
-; AVX512-NEXT:    shldq $63, %rax, %r12
-; AVX512-NEXT:    movq (%rsp), %rcx # 8-byte Reload
+; AVX512-NEXT:    shldq $63, %rax, %rdx
 ; AVX512-NEXT:    movq {{[-0-9]+}}(%r{{[sb]}}p), %rax # 8-byte Reload
+; AVX512-NEXT:    movq {{[-0-9]+}}(%r{{[sb]}}p), %rcx # 8-byte Reload
 ; AVX512-NEXT:    shldq $63, %rax, %rcx
+; AVX512-NEXT:    movq (%rsp), %rax # 8-byte Reload
+; AVX512-NEXT:    shldq $63, %rax, %r9
 ; AVX512-NEXT:    movq {{[-0-9]+}}(%r{{[sb]}}p), %rax # 8-byte Reload
-; AVX512-NEXT:    shldq $63, %rax, %r14
+; AVX512-NEXT:    shldq $63, %rax, %r10
 ; AVX512-NEXT:    movq {{[-0-9]+}}(%r{{[sb]}}p), %rax # 8-byte Reload
-; AVX512-NEXT:    shldq $63, %rax, %r15
+; AVX512-NEXT:    shldq $63, %rax, %rsi
 ; AVX512-NEXT:    movq {{[-0-9]+}}(%r{{[sb]}}p), %rax # 8-byte Reload
-; AVX512-NEXT:    shldq $63, %rax, %rdi
+; AVX512-NEXT:    shldq $63, %rax, %r14
 ; AVX512-NEXT:    movq {{[-0-9]+}}(%r{{[sb]}}p), %rax # 8-byte Reload
-; AVX512-NEXT:    shldq $63, %rax, %r11
-; AVX512-NEXT:    vmovq %r11, %xmm0
-; AVX512-NEXT:    vmovq %rdi, %xmm1
+; AVX512-NEXT:    shldq $63, %rax, %r15
+; AVX512-NEXT:    vmovq %r15, %xmm0
+; AVX512-NEXT:    vmovq %r14, %xmm1
+; AVX512-NEXT:    vmovq %r10, %xmm2
 ; AVX512-NEXT:    vinserti128 $1, %xmm1, %ymm0, %ymm0
-; AVX512-NEXT:    vextracti128 $1, %ymm0, %xmm1
-; AVX512-NEXT:    vmovd %xmm1, %eax
-; AVX512-NEXT:    vpinsrb $1, %eax, %xmm0, %xmm1
-; AVX512-NEXT:    vmovq %r15, %xmm2
-; AVX512-NEXT:    vmovq %r14, %xmm3
-; AVX512-NEXT:    vinserti128 $1, %xmm3, %ymm2, %ymm2
-; AVX512-NEXT:    vinserti64x4 $1, %ymm2, %zmm0, %zmm0
+; AVX512-NEXT:    vmovq %rsi, %xmm1
+; AVX512-NEXT:    vinserti128 $1, %xmm2, %ymm1, %ymm1
+; AVX512-NEXT:    vinserti64x4 $1, %ymm0, %zmm1, %zmm0
 ; AVX512-NEXT:    vextracti32x4 $2, %zmm0, %xmm2
+; AVX512-NEXT:    vextracti128 $1, %ymm1, %xmm1
+; AVX512-NEXT:    vmovd %esi, %xmm3
+; AVX512-NEXT:    vmovd %xmm1, %eax
+; AVX512-NEXT:    vpinsrb $1, %eax, %xmm3, %xmm1
 ; AVX512-NEXT:    vmovd %xmm2, %eax
 ; AVX512-NEXT:    vpinsrb $2, %eax, %xmm1, %xmm1
 ; AVX512-NEXT:    vextracti32x4 $3, %zmm0, %xmm0
 ; AVX512-NEXT:    vmovd %xmm0, %eax
 ; AVX512-NEXT:    vpinsrb $3, %eax, %xmm1, %xmm0
-; AVX512-NEXT:    vmovq %rcx, %xmm1
-; AVX512-NEXT:    vmovq %r12, %xmm2
+; AVX512-NEXT:    vpinsrb $4, %r9d, %xmm0, %xmm0
+; AVX512-NEXT:    vmovq %r9, %xmm1
+; AVX512-NEXT:    vmovq %rcx, %xmm2
 ; AVX512-NEXT:    vinserti128 $1, %xmm2, %ymm1, %ymm1
-; AVX512-NEXT:    vmovd %xmm1, %eax
-; AVX512-NEXT:    vpinsrb $4, %eax, %xmm0, %xmm0
 ; AVX512-NEXT:    vextracti128 $1, %ymm1, %xmm2
 ; AVX512-NEXT:    vmovd %xmm2, %eax
 ; AVX512-NEXT:    vpinsrb $5, %eax, %xmm0, %xmm0
 ; AVX512-NEXT:    vmovq %rdx, %xmm2
-; AVX512-NEXT:    vmovq %rsi, %xmm3
+; AVX512-NEXT:    vmovq %rdi, %xmm3
 ; AVX512-NEXT:    vinserti128 $1, %xmm3, %ymm2, %ymm2
 ; AVX512-NEXT:    vinserti64x4 $1, %ymm2, %zmm1, %zmm1
 ; AVX512-NEXT:    vextracti32x4 $2, %zmm1, %xmm2
@@ -2475,16 +2477,16 @@
 ; AVX512-NEXT:    vextracti32x4 $3, %zmm1, %xmm1
 ; AVX512-NEXT:    vmovd %xmm1, %eax
 ; AVX512-NEXT:    vpinsrb $7, %eax, %xmm0, %xmm0
+; AVX512-NEXT:    movq %rbx, %rax
+; AVX512-NEXT:    vpinsrb $8, %eax, %xmm0, %xmm0
 ; AVX512-NEXT:    vmovq %rbx, %xmm1
-; AVX512-NEXT:    vmovq %r13, %xmm2
+; AVX512-NEXT:    vmovq %rbp, %xmm2
 ; AVX512-NEXT:    vinserti128 $1, %xmm2, %ymm1, %ymm1
-; AVX512-NEXT:    vmovd %xmm1, %eax
-; AVX512-NEXT:    vpinsrb $8, %eax, %xmm0, %xmm0
 ; AVX512-NEXT:    vextracti128 $1, %ymm1, %xmm2
 ; AVX512-NEXT:    vmovd %xmm2, %eax
 ; AVX512-NEXT:    vpinsrb $9, %eax, %xmm0, %xmm0
-; AVX512-NEXT:    vmovq %r8, %xmm2
-; AVX512-NEXT:    vmovq %r10, %xmm3
+; AVX512-NEXT:    vmovq %r12, %xmm2
+; AVX512-NEXT:    vmovq %r11, %xmm3
 ; AVX512-NEXT:    vinserti128 $1, %xmm3, %ymm2, %ymm2
 ; AVX512-NEXT:    vinserti64x4 $1, %ymm2, %zmm1, %zmm1
 ; AVX512-NEXT:    vextracti32x4 $2, %zmm1, %xmm2
@@ -2493,11 +2495,10 @@
 ; AVX512-NEXT:    vextracti32x4 $3, %zmm1, %xmm1
 ; AVX512-NEXT:    vmovd %xmm1, %eax
 ; AVX512-NEXT:    vpinsrb $11, %eax, %xmm0, %xmm0
-; AVX512-NEXT:    vmovq %r9, %xmm1
-; AVX512-NEXT:    vmovq %rbp, %xmm2
+; AVX512-NEXT:    vpinsrb $12, %r13d, %xmm0, %xmm0
+; AVX512-NEXT:    vmovq %r13, %xmm1
+; AVX512-NEXT:    vmovq %r8, %xmm2
 ; AVX512-NEXT:    vinserti128 $1, %xmm2, %ymm1, %ymm1
-; AVX512-NEXT:    vmovd %xmm1, %eax
-; AVX512-NEXT:    vpinsrb $12, %eax, %xmm0, %xmm0
 ; AVX512-NEXT:    vextracti128 $1, %ymm1, %xmm2
 ; AVX512-NEXT:    vmovd %xmm2, %eax
 ; AVX512-NEXT:    vpinsrb $13, %eax, %xmm0, %xmm0
diff --git a/llvm/test/CodeGen/X86/horizontal-sum.ll b/llvm/test/CodeGen/X86/horizontal-sum.ll
--- a/llvm/test/CodeGen/X86/horizontal-sum.ll
+++ b/llvm/test/CodeGen/X86/horizontal-sum.ll
@@ -229,13 +229,13 @@
 ; AVX1-SLOW-NEXT:    vshufps {{.*#+}} xmm1 = xmm2[1,3],xmm1[1,3]
 ; AVX1-SLOW-NEXT:    vblendps {{.*#+}} xmm1 = xmm1[0,1,2],xmm4[3]
 ; AVX1-SLOW-NEXT:    vaddps %xmm1, %xmm3, %xmm1
-; AVX1-SLOW-NEXT:    vmovlhps {{.*#+}} xmm0 = xmm0[0],xmm1[0]
-; AVX1-SLOW-NEXT:    vpermilpd {{.*#+}} xmm1 = xmm1[1,0]
-; AVX1-SLOW-NEXT:    vinsertf128 $1, %xmm1, %ymm0, %ymm1
+; AVX1-SLOW-NEXT:    vpermilpd {{.*#+}} xmm2 = xmm1[1,0]
+; AVX1-SLOW-NEXT:    vinsertf128 $1, %xmm2, %ymm0, %ymm0
+; AVX1-SLOW-NEXT:    vmovddup {{.*#+}} xmm1 = xmm1[0,0]
 ; AVX1-SLOW-NEXT:    vhaddps %xmm7, %xmm6, %xmm2
 ; AVX1-SLOW-NEXT:    vhaddps %xmm2, %xmm2, %xmm2
-; AVX1-SLOW-NEXT:    vinsertf128 $1, %xmm2, %ymm0, %ymm0
-; AVX1-SLOW-NEXT:    vshufpd {{.*#+}} ymm0 = ymm1[0],ymm0[1],ymm1[2],ymm0[2]
+; AVX1-SLOW-NEXT:    vinsertf128 $1, %xmm2, %ymm1, %ymm1
+; AVX1-SLOW-NEXT:    vshufpd {{.*#+}} ymm0 = ymm0[0],ymm1[1],ymm0[2],ymm1[2]
 ; AVX1-SLOW-NEXT:    retq
 ;
 ; AVX1-FAST-LABEL: pair_sum_v8f32_v4f32:
@@ -250,13 +250,13 @@
 ; AVX1-FAST-NEXT:    vshufps {{.*#+}} xmm1 = xmm2[1,3],xmm1[1,3]
 ; AVX1-FAST-NEXT:    vblendps {{.*#+}} xmm1 = xmm1[0,1,2],xmm4[3]
 ; AVX1-FAST-NEXT:    vaddps %xmm1, %xmm3, %xmm1
-; AVX1-FAST-NEXT:    vmovlhps {{.*#+}} xmm0 = xmm0[0],xmm1[0]
-; AVX1-FAST-NEXT:    vpermilpd {{.*#+}} xmm1 = xmm1[1,0]
-; AVX1-FAST-NEXT:    vinsertf128 $1, %xmm1, %ymm0, %ymm1
+; AVX1-FAST-NEXT:    vpermilpd {{.*#+}} xmm2 = xmm1[1,0]
+; AVX1-FAST-NEXT:    vinsertf128 $1, %xmm2, %ymm0, %ymm0
+; AVX1-FAST-NEXT:    vmovddup {{.*#+}} xmm1 = xmm1[0,0]
 ; AVX1-FAST-NEXT:    vhaddps %xmm7, %xmm6, %xmm2
 ; AVX1-FAST-NEXT:    vhaddps %xmm0, %xmm2, %xmm2
-; AVX1-FAST-NEXT:    vinsertf128 $1, %xmm2, %ymm0, %ymm0
-; AVX1-FAST-NEXT:    vshufpd {{.*#+}} ymm0 = ymm1[0],ymm0[1],ymm1[2],ymm0[2]
+; AVX1-FAST-NEXT:    vinsertf128 $1, %xmm2, %ymm1, %ymm1
+; AVX1-FAST-NEXT:    vshufpd {{.*#+}} ymm0 = ymm0[0],ymm1[1],ymm0[2],ymm1[2]
 ; AVX1-FAST-NEXT:    retq
 ;
 ; AVX2-SLOW-LABEL: pair_sum_v8f32_v4f32:
@@ -273,13 +273,13 @@
 ; AVX2-SLOW-NEXT:    vshufps {{.*#+}} xmm1 = xmm2[1,3],xmm1[1,3]
 ; AVX2-SLOW-NEXT:    vblendps {{.*#+}} xmm1 = xmm1[0,1,2],xmm4[3]
 ; AVX2-SLOW-NEXT:    vaddps %xmm1, %xmm3, %xmm1
-; AVX2-SLOW-NEXT:    vmovlhps {{.*#+}} xmm0 = xmm0[0],xmm1[0]
-; AVX2-SLOW-NEXT:    vpermilpd {{.*#+}} xmm1 = xmm1[1,0]
-; AVX2-SLOW-NEXT:    vinsertf128 $1, %xmm1, %ymm0, %ymm1
+; AVX2-SLOW-NEXT:    vpermilpd {{.*#+}} xmm2 = xmm1[1,0]
+; AVX2-SLOW-NEXT:    vinsertf128 $1, %xmm2, %ymm0, %ymm0
+; AVX2-SLOW-NEXT:    vmovddup {{.*#+}} xmm1 = xmm1[0,0]
 ; AVX2-SLOW-NEXT:    vhaddps %xmm7, %xmm6, %xmm2
 ; AVX2-SLOW-NEXT:    vhaddps %xmm2, %xmm2, %xmm2
-; AVX2-SLOW-NEXT:    vinsertf128 $1, %xmm2, %ymm0, %ymm0
-; AVX2-SLOW-NEXT:    vshufpd {{.*#+}} ymm0 = ymm1[0],ymm0[1],ymm1[2],ymm0[2]
+; AVX2-SLOW-NEXT:    vinsertf128 $1, %xmm2, %ymm1, %ymm1
+; AVX2-SLOW-NEXT:    vshufpd {{.*#+}} ymm0 = ymm0[0],ymm1[1],ymm0[2],ymm1[2]
 ; AVX2-SLOW-NEXT:    retq
 ;
 ; AVX2-FAST-LABEL: pair_sum_v8f32_v4f32:
@@ -294,13 +294,13 @@
 ; AVX2-FAST-NEXT:    vshufps {{.*#+}} xmm1 = xmm2[1,3],xmm1[1,3]
 ; AVX2-FAST-NEXT:    vblendps {{.*#+}} xmm1 = xmm1[0,1,2],xmm4[3]
 ; AVX2-FAST-NEXT:    vaddps %xmm1, %xmm3, %xmm1
-; AVX2-FAST-NEXT:    vmovlhps {{.*#+}} xmm0 = xmm0[0],xmm1[0]
-; AVX2-FAST-NEXT:    vpermilpd {{.*#+}} xmm1 = xmm1[1,0]
-; AVX2-FAST-NEXT:    vinsertf128 $1, %xmm1, %ymm0, %ymm1
+; AVX2-FAST-NEXT:    vpermilpd {{.*#+}} xmm2 = xmm1[1,0]
+; AVX2-FAST-NEXT:    vinsertf128 $1, %xmm2, %ymm0, %ymm0
+; AVX2-FAST-NEXT:    vmovddup {{.*#+}} xmm1 = xmm1[0,0]
 ; AVX2-FAST-NEXT:    vhaddps %xmm7, %xmm6, %xmm2
 ; AVX2-FAST-NEXT:    vhaddps %xmm0, %xmm2, %xmm2
-; AVX2-FAST-NEXT:    vinsertf128 $1, %xmm2, %ymm0, %ymm0
-; AVX2-FAST-NEXT:    vshufpd {{.*#+}} ymm0 = ymm1[0],ymm0[1],ymm1[2],ymm0[2]
+; AVX2-FAST-NEXT:    vinsertf128 $1, %xmm2, %ymm1, %ymm1
+; AVX2-FAST-NEXT:    vshufpd {{.*#+}} ymm0 = ymm0[0],ymm1[1],ymm0[2],ymm1[2]
 ; AVX2-FAST-NEXT:    retq
   %9 = shufflevector <4 x float> %0, <4 x float> poison, <2 x i32> <i32 0, i32 2>
   %10 = shufflevector <4 x float> %0, <4 x float> poison, <2 x i32> <i32 1, i32 3>
@@ -399,13 +399,13 @@
 ; AVX1-SLOW-NEXT:    vshufps {{.*#+}} xmm1 = xmm2[1,3],xmm1[1,3]
 ; AVX1-SLOW-NEXT:    vblendps {{.*#+}} xmm1 = xmm1[0,1,2],xmm4[3]
 ; AVX1-SLOW-NEXT:    vpaddd %xmm1, %xmm3, %xmm1
-; AVX1-SLOW-NEXT:    vpunpcklqdq {{.*#+}} xmm0 = xmm0[0],xmm1[0]
-; AVX1-SLOW-NEXT:    vpshufd {{.*#+}} xmm1 = xmm1[2,3,2,3]
-; AVX1-SLOW-NEXT:    vinsertf128 $1, %xmm1, %ymm0, %ymm1
+; AVX1-SLOW-NEXT:    vpshufd {{.*#+}} xmm2 = xmm1[2,3,2,3]
+; AVX1-SLOW-NEXT:    vinsertf128 $1, %xmm2, %ymm0, %ymm0
+; AVX1-SLOW-NEXT:    vpshufd {{.*#+}} xmm1 = xmm1[0,1,0,1]
 ; AVX1-SLOW-NEXT:    vphaddd %xmm7, %xmm6, %xmm2
 ; AVX1-SLOW-NEXT:    vphaddd %xmm2, %xmm2, %xmm2
-; AVX1-SLOW-NEXT:    vinsertf128 $1, %xmm2, %ymm0, %ymm0
-; AVX1-SLOW-NEXT:    vshufpd {{.*#+}} ymm0 = ymm1[0],ymm0[1],ymm1[2],ymm0[2]
+; AVX1-SLOW-NEXT:    vinsertf128 $1, %xmm2, %ymm1, %ymm1
+; AVX1-SLOW-NEXT:    vshufpd {{.*#+}} ymm0 = ymm0[0],ymm1[1],ymm0[2],ymm1[2]
 ; AVX1-SLOW-NEXT:    retq
 ;
 ; AVX1-FAST-LABEL: pair_sum_v8i32_v4i32:
@@ -422,13 +422,13 @@
 ; AVX1-FAST-NEXT:    vshufps {{.*#+}} xmm1 = xmm2[1,3],xmm1[1,3]
 ; AVX1-FAST-NEXT:    vblendps {{.*#+}} xmm1 = xmm1[0,1,2],xmm4[3]
 ; AVX1-FAST-NEXT:    vpaddd %xmm1, %xmm3, %xmm1
-; AVX1-FAST-NEXT:    vpunpcklqdq {{.*#+}} xmm0 = xmm0[0],xmm1[0]
-; AVX1-FAST-NEXT:    vpshufd {{.*#+}} xmm1 = xmm1[2,3,2,3]
-; AVX1-FAST-NEXT:    vinsertf128 $1, %xmm1, %ymm0, %ymm1
+; AVX1-FAST-NEXT:    vpshufd {{.*#+}} xmm2 = xmm1[2,3,2,3]
+; AVX1-FAST-NEXT:    vinsertf128 $1, %xmm2, %ymm0, %ymm0
+; AVX1-FAST-NEXT:    vpshufd {{.*#+}} xmm1 = xmm1[0,1,0,1]
 ; AVX1-FAST-NEXT:    vphaddd %xmm7, %xmm6, %xmm2
 ; AVX1-FAST-NEXT:    vphaddd %xmm0, %xmm2, %xmm2
-; AVX1-FAST-NEXT:    vinsertf128 $1, %xmm2, %ymm0, %ymm0
-; AVX1-FAST-NEXT:    vshufpd {{.*#+}} ymm0 = ymm1[0],ymm0[1],ymm1[2],ymm0[2]
+; AVX1-FAST-NEXT:    vinsertf128 $1, %xmm2, %ymm1, %ymm1
+; AVX1-FAST-NEXT:    vshufpd {{.*#+}} ymm0 = ymm0[0],ymm1[1],ymm0[2],ymm1[2]
 ; AVX1-FAST-NEXT:    retq
 ;
 ; AVX2-SLOW-LABEL: pair_sum_v8i32_v4i32: