diff --git a/llvm/lib/Target/AArch64/AArch64TargetTransformInfo.cpp b/llvm/lib/Target/AArch64/AArch64TargetTransformInfo.cpp
--- a/llvm/lib/Target/AArch64/AArch64TargetTransformInfo.cpp
+++ b/llvm/lib/Target/AArch64/AArch64TargetTransformInfo.cpp
@@ -1436,7 +1436,7 @@
   return std::nullopt;
 }
 
-bool SimplifyValuePattern(SmallVector<Value *> &Vec) {
+bool SimplifyValuePattern(SmallVector<Value *> &Vec, bool AllowPoison) {
   size_t VecSize = Vec.size();
   if (VecSize == 1)
     return true;
@@ -1446,13 +1446,20 @@
 
   for (auto LHS = Vec.begin(), RHS = Vec.begin() + HalfVecSize;
        RHS != Vec.end(); LHS++, RHS++) {
-    if (*LHS != nullptr && *RHS != nullptr && *LHS == *RHS)
-      continue;
-    return false;
+    if (*LHS != nullptr && *RHS != nullptr) {
+      if (*LHS == *RHS)
+        continue;
+      else
+        return false;
+    }
+    if (!AllowPoison)
+      return false;
+    if (*LHS == nullptr && *RHS != nullptr)
+      *LHS = *RHS;
   }
 
   Vec.resize(HalfVecSize);
-  SimplifyValuePattern(Vec);
+  SimplifyValuePattern(Vec, AllowPoison);
   return true;
 }
 
@@ -1476,7 +1483,9 @@
     CurrentInsertElt = InsertElt->getOperand(0);
   }
 
-  if (!SimplifyValuePattern(Elts))
+  bool AllowPoison =
+      isa<PoisonValue>(CurrentInsertElt) && isa<PoisonValue>(Default);
+  if (!SimplifyValuePattern(Elts, AllowPoison))
     return std::nullopt;
 
   // Rebuild the simplified chain of InsertElements. e.g. (a, b, a, b) as (a, b)
@@ -1484,9 +1493,13 @@
   Builder.SetInsertPoint(&II);
   Value *InsertEltChain = PoisonValue::get(CurrentInsertElt->getType());
   for (size_t I = 0; I < Elts.size(); I++) {
+    if (Elts[I] == nullptr)
+      continue;
     InsertEltChain = Builder.CreateInsertElement(InsertEltChain, Elts[I],
                                                  Builder.getInt64(I));
   }
+  if (InsertEltChain == nullptr)
+    return std::nullopt;
 
   // Splat the simplified sequence, e.g. (f16 a, f16 b, f16 c, f16 d) as one i64
   // value or (f16 a, f16 b) as one i32 value. This requires an InsertSubvector
diff --git a/llvm/test/Transforms/InstCombine/AArch64/sve-intrinsic-dupqlane.ll b/llvm/test/Transforms/InstCombine/AArch64/sve-intrinsic-dupqlane.ll
--- a/llvm/test/Transforms/InstCombine/AArch64/sve-intrinsic-dupqlane.ll
+++ b/llvm/test/Transforms/InstCombine/AArch64/sve-intrinsic-dupqlane.ll
@@ -96,12 +96,11 @@
 ; CHECK-NEXT:    [[TMP1:%.*]] = insertelement <8 x half> poison, half [[A:%.*]], i64 0
 ; CHECK-NEXT:    [[TMP2:%.*]] = insertelement <8 x half> [[TMP1]], half [[B:%.*]], i64 1
 ; CHECK-NEXT:    [[TMP3:%.*]] = insertelement <8 x half> [[TMP2]], half [[C:%.*]], i64 2
-; CHECK-NEXT:    [[TMP4:%.*]] = insertelement <8 x half> [[TMP3]], half [[A]], i64 4
-; CHECK-NEXT:    [[TMP5:%.*]] = insertelement <8 x half> [[TMP4]], half [[B]], i64 5
-; CHECK-NEXT:    [[TMP6:%.*]] = insertelement <8 x half> [[TMP5]], half [[C]], i64 6
-; CHECK-NEXT:    [[TMP7:%.*]] = tail call <vscale x 8 x half> @llvm.vector.insert.nxv8f16.v8f16(<vscale x 8 x half> poison, <8 x half> [[TMP6]], i64 0)
-; CHECK-NEXT:    [[TMP8:%.*]] = tail call <vscale x 8 x half> @llvm.aarch64.sve.dupq.lane.nxv8f16(<vscale x 8 x half> [[TMP7]], i64 0)
-; CHECK-NEXT:    ret <vscale x 8 x half> [[TMP8]]
+; CHECK-NEXT:    [[TMP4:%.*]] = call <vscale x 8 x half> @llvm.vector.insert.nxv8f16.v8f16(<vscale x 8 x half> poison, <8 x half> [[TMP3]], i64 0)
+; CHECK-NEXT:    [[TMP5:%.*]] = bitcast <vscale x 8 x half> [[TMP4]] to <vscale x 2 x i64>
+; CHECK-NEXT:    [[TMP6:%.*]] = shufflevector <vscale x 2 x i64> [[TMP5]], <vscale x 2 x i64> poison, <vscale x 2 x i32> zeroinitializer
+; CHECK-NEXT:    [[TMP7:%.*]] = bitcast <vscale x 2 x i64> [[TMP6]] to <vscale x 8 x half>
+; CHECK-NEXT:    ret <vscale x 8 x half> [[TMP7]]
 ;
   %1 = insertelement <8 x half> poison, half %a, i64 0
   %2 = insertelement <8 x half> %1, half %b, i64 1
@@ -114,6 +113,57 @@
   ret <vscale x 8 x half> %8
 }
 
+define dso_local <vscale x 8 x half> @dupq_f16_abnull_pattern(half %a, half %b) {
+; CHECK-LABEL: @dupq_f16_abnull_pattern(
+; CHECK-NEXT:    [[TMP1:%.*]] = insertelement <8 x half> poison, half [[A:%.*]], i64 0
+; CHECK-NEXT:    [[TMP2:%.*]] = insertelement <8 x half> [[TMP1]], half [[B:%.*]], i64 1
+; CHECK-NEXT:    [[TMP3:%.*]] = call <vscale x 8 x half> @llvm.vector.insert.nxv8f16.v8f16(<vscale x 8 x half> poison, <8 x half> [[TMP2]], i64 0)
+; CHECK-NEXT:    [[TMP4:%.*]] = bitcast <vscale x 8 x half> [[TMP3]] to <vscale x 4 x i32>
+; CHECK-NEXT:    [[TMP5:%.*]] = shufflevector <vscale x 4 x i32> [[TMP4]], <vscale x 4 x i32> poison, <vscale x 4 x i32> zeroinitializer
+; CHECK-NEXT:    [[TMP6:%.*]] = bitcast <vscale x 4 x i32> [[TMP5]] to <vscale x 8 x half>
+; CHECK-NEXT:    ret <vscale x 8 x half> [[TMP6]]
+;
+  %1 = insertelement <8 x half> poison, half %a, i64 0
+  %2 = insertelement <8 x half> %1, half %b, i64 1
+  %3 = tail call <vscale x 8 x half> @llvm.vector.insert.nxv8f16.v8f16(<vscale x 8 x half> poison, <8 x half> %2, i64 0)
+  %4 = tail call <vscale x 8 x half> @llvm.aarch64.sve.dupq.lane.nxv8f16(<vscale x 8 x half> %3, i64 0)
+  ret <vscale x 8 x half> %4
+}
+
+define dso_local <vscale x 8 x half> @neg_dupq_f16_non_poison_fixed(half %a, half %b, <8 x half> %v) {
+; CHECK-LABEL: @neg_dupq_f16_non_poison_fixed(
+; CHECK-NEXT:    [[TMP1:%.*]] = insertelement <8 x half> [[V:%.*]], half [[A:%.*]], i64 0
+; CHECK-NEXT:    [[TMP2:%.*]] = insertelement <8 x half> [[TMP1]], half [[B:%.*]], i64 1
+; CHECK-NEXT:    [[TMP3:%.*]] = tail call <vscale x 8 x half> @llvm.vector.insert.nxv8f16.v8f16(<vscale x 8 x half> poison, <8 x half> [[TMP2]], i64 0)
+; CHECK-NEXT:    [[TMP4:%.*]] = tail call <vscale x 8 x half> @llvm.aarch64.sve.dupq.lane.nxv8f16(<vscale x 8 x half> [[TMP3]], i64 0)
+; CHECK-NEXT:    ret <vscale x 8 x half> [[TMP4]]
+;
+  %1 = insertelement <8 x half> %v, half %a, i64 0
+  %2 = insertelement <8 x half> %1, half %b, i64 1
+  %3 = insertelement <8 x half> %2, half %a, i64 0
+  %4 = insertelement <8 x half> %3, half %b, i64 1
+  %5 = tail call <vscale x 8 x half> @llvm.vector.insert.nxv8f16.v8f16(<vscale x 8 x half> poison, <8 x half> %4, i64 0)
+  %6 = tail call <vscale x 8 x half> @llvm.aarch64.sve.dupq.lane.nxv8f16(<vscale x 8 x half> %5, i64 0)
+  ret <vscale x 8 x half> %6
+}
+
+define dso_local <vscale x 8 x half> @neg_dupq_f16_into_non_poison_scalable(half %a, half %b, <vscale x 8 x half> %v) {
+; CHECK-LABEL: @neg_dupq_f16_into_non_poison_scalable(
+; CHECK-NEXT:    [[TMP1:%.*]] = insertelement <8 x half> poison, half [[A:%.*]], i64 0
+; CHECK-NEXT:    [[TMP2:%.*]] = insertelement <8 x half> [[TMP1]], half [[B:%.*]], i64 1
+; CHECK-NEXT:    [[TMP3:%.*]] = tail call <vscale x 8 x half> @llvm.vector.insert.nxv8f16.v8f16(<vscale x 8 x half> [[V:%.*]], <8 x half> [[TMP2]], i64 0)
+; CHECK-NEXT:    [[TMP4:%.*]] = tail call <vscale x 8 x half> @llvm.aarch64.sve.dupq.lane.nxv8f16(<vscale x 8 x half> [[TMP3]], i64 0)
+; CHECK-NEXT:    ret <vscale x 8 x half> [[TMP4]]
+;
+  %1 = insertelement <8 x half> poison, half %a, i64 0
+  %2 = insertelement <8 x half> %1, half %b, i64 1
+  %3 = insertelement <8 x half> %2, half %a, i64 0
+  %4 = insertelement <8 x half> %3, half %b, i64 1
+  %5 = tail call <vscale x 8 x half> @llvm.vector.insert.nxv8f16.v8f16(<vscale x 8 x half> %v, <8 x half> %4, i64 0)
+  %6 = tail call <vscale x 8 x half> @llvm.aarch64.sve.dupq.lane.nxv8f16(<vscale x 8 x half> %5, i64 0)
+  ret <vscale x 8 x half> %6
+}
+
 ; Insert %c to override the last element in the insertelement chain, which will fail to combine
 
 define dso_local <vscale x 8 x half> @neg_dupq_f16_abcd_pattern_double_insert(half %a, half %b, half %c, half %d) {