Index: llvm/lib/Target/ARM/ARMISelLowering.cpp
===================================================================
--- llvm/lib/Target/ARM/ARMISelLowering.cpp
+++ llvm/lib/Target/ARM/ARMISelLowering.cpp
@@ -16706,14 +16706,16 @@
   EVT VT = N->getValueType(0);
   SDLoc DL(N);
 
-  // The identity element for a fadd is -0.0, which these VMOV's represent.
-  auto isNegativeZeroSplat = [&](SDValue Op) {
+  // The identity element for a fadd is -0.0 or +0.0 when the nsz flag is set,
+  // which these VMOV's represent.
+  auto isIdentitySplat = [&](SDValue Op, bool NSZ) {
     if (Op.getOpcode() != ISD::BITCAST ||
         Op.getOperand(0).getOpcode() != ARMISD::VMOVIMM)
       return false;
-    if (VT == MVT::v4f32 && Op.getOperand(0).getConstantOperandVal(0) == 1664)
+    uint64_t ImmVal = Op.getOperand(0).getConstantOperandVal(0);
+    if (VT == MVT::v4f32 && (ImmVal == 1664 || (ImmVal == 0 && NSZ)))
       return true;
-    if (VT == MVT::v8f16 && Op.getOperand(0).getConstantOperandVal(0) == 2688)
+    if (VT == MVT::v8f16 && (ImmVal == 2688 || (ImmVal == 0 && NSZ)))
       return true;
     return false;
   };
@@ -16721,12 +16723,15 @@
   if (Op0.getOpcode() == ISD::VSELECT && Op1.getOpcode() != ISD::VSELECT)
     std::swap(Op0, Op1);
 
-  if (Op1.getOpcode() != ISD::VSELECT ||
-      !isNegativeZeroSplat(Op1.getOperand(2)))
+  if (Op1.getOpcode() != ISD::VSELECT)
+    return SDValue();
+
+  SDNodeFlags SelFlags = Op1->getFlags();
+  if (!isIdentitySplat(Op1.getOperand(2), SelFlags.hasNoSignedZeros()))
     return SDValue();
   SDValue FAdd =
       DAG.getNode(ISD::FADD, DL, VT, Op0, Op1.getOperand(1), N->getFlags());
-  return DAG.getNode(ISD::VSELECT, DL, VT, Op1.getOperand(0), FAdd, Op0);
+  return DAG.getNode(ISD::VSELECT, DL, VT, Op1.getOperand(0), FAdd, Op0, SelFlags);
 }
 
 /// PerformVDIVCombine - VCVT (fixed-point to floating-point, Advanced SIMD)
Index: llvm/test/CodeGen/Thumb2/mve-pred-selectop3.ll
===================================================================
--- llvm/test/CodeGen/Thumb2/mve-pred-selectop3.ll
+++ llvm/test/CodeGen/Thumb2/mve-pred-selectop3.ll
@@ -363,6 +363,36 @@
   ret <4 x float> %b
 }
 
+define arm_aapcs_vfpcc <4 x float> @fadd_v4f32_x2(<4 x float> %x, <4 x float> %y, i32 %n) {
+; CHECK-LABEL: fadd_v4f32_x2:
+; CHECK:       @ %bb.0: @ %entry
+; CHECK-NEXT:    vmov.i32 q2, #0x0
+; CHECK-NEXT:    vctp.32 r0
+; CHECK-NEXT:    vpst
+; CHECK-NEXT:    vmovt q2, q1
+; CHECK-NEXT:    vadd.f32 q0, q2, q0
+; CHECK-NEXT:    bx lr
+entry:
+  %c = call <4 x i1> @llvm.arm.mve.vctp32(i32 %n)
+  %a = select <4 x i1> %c, <4 x float> %y, <4 x float> <float 0.000000e+00, float 0.000000e+00, float 0.000000e+00, float 0.000000e+00>
+  %b = fadd <4 x float> %a, %x
+  ret <4 x float> %b
+}
+
+define arm_aapcs_vfpcc <4 x float> @fadd_v4f32_x3(<4 x float> %x, <4 x float> %y, i32 %n) {
+; CHECK-LABEL: fadd_v4f32_x3:
+; CHECK:       @ %bb.0: @ %entry
+; CHECK-NEXT:    vctp.32 r0
+; CHECK-NEXT:    vpst
+; CHECK-NEXT:    vaddt.f32 q0, q0, q1
+; CHECK-NEXT:    bx lr
+entry:
+  %c = call <4 x i1> @llvm.arm.mve.vctp32(i32 %n)
+  %a = select nsz <4 x i1> %c, <4 x float> %y, <4 x float> <float 0.000000e+00, float 0.000000e+00, float 0.000000e+00, float 0.000000e+00>
+  %b = fadd nsz <4 x float> %a, %x
+  ret <4 x float> %b
+}
+
 define arm_aapcs_vfpcc <8 x half> @fadd_v8f16_x(<8 x half> %x, <8 x half> %y, i32 %n) {
 ; CHECK-LABEL: fadd_v8f16_x:
 ; CHECK:       @ %bb.0: @ %entry
@@ -377,6 +407,36 @@
   ret <8 x half> %b
 }
 
+define arm_aapcs_vfpcc <8 x half> @fadd_v8f16_x2(<8 x half> %x, <8 x half> %y, i32 %n) {
+; CHECK-LABEL: fadd_v8f16_x2:
+; CHECK:       @ %bb.0: @ %entry
+; CHECK-NEXT:    vmov.i32 q2, #0x0
+; CHECK-NEXT:    vctp.16 r0
+; CHECK-NEXT:    vpst
+; CHECK-NEXT:    vmovt q2, q1
+; CHECK-NEXT:    vadd.f16 q0, q2, q0
+; CHECK-NEXT:    bx lr
+entry:
+  %c = call <8 x i1> @llvm.arm.mve.vctp16(i32 %n)
+  %a = select <8 x i1> %c, <8 x half> %y, <8 x half> <half 0x0000, half 0x00000, half 0x00000, half 0x00000, half 0x00000, half 0x00000, half 0x00000, half 0x00000>
+  %b = fadd <8 x half> %a, %x
+  ret <8 x half> %b
+}
+
+define arm_aapcs_vfpcc <8 x half> @fadd_v8f16_x3(<8 x half> %x, <8 x half> %y, i32 %n) {
+; CHECK-LABEL: fadd_v8f16_x3:
+; CHECK:       @ %bb.0: @ %entry
+; CHECK-NEXT:    vctp.16 r0
+; CHECK-NEXT:    vpst
+; CHECK-NEXT:    vaddt.f16 q0, q0, q1
+; CHECK-NEXT:    bx lr
+entry:
+  %c = call <8 x i1> @llvm.arm.mve.vctp16(i32 %n)
+  %a = select nsz <8 x i1> %c, <8 x half> %y, <8 x half> <half 0x0000, half 0x00000, half 0x00000, half 0x00000, half 0x00000, half 0x00000, half 0x00000, half 0x00000>
+  %b = fadd nsz <8 x half> %a, %x
+  ret <8 x half> %b
+}
+
 define arm_aapcs_vfpcc <4 x float> @fsub_v4f32_x(<4 x float> %x, <4 x float> %y, i32 %n) {
 ; CHECK-LABEL: fsub_v4f32_x:
 ; CHECK:       @ %bb.0: @ %entry