diff --git a/llvm/lib/Transforms/InstCombine/InstCombineCalls.cpp b/llvm/lib/Transforms/InstCombine/InstCombineCalls.cpp
index cf6d0ecab4f69..e1e24a99d0474 100644
--- a/llvm/lib/Transforms/InstCombine/InstCombineCalls.cpp
+++ b/llvm/lib/Transforms/InstCombine/InstCombineCalls.cpp
@@ -318,18 +318,18 @@ Value *InstCombinerImpl::simplifyMaskedLoad(IntrinsicInst &II) {
 // * Single constant active lane -> store
 // * Narrow width by halfs excluding zero/undef lanes
 Instruction *InstCombinerImpl::simplifyMaskedStore(IntrinsicInst &II) {
+  Value *StorePtr = II.getArgOperand(1);
+  Align Alignment = cast<ConstantInt>(II.getArgOperand(2))->getAlignValue();
   auto *ConstMask = dyn_cast<Constant>(II.getArgOperand(3));
   if (!ConstMask)
     return nullptr;
 
   // If the mask is all zeros, this instruction does nothing.
-  if (ConstMask->isNullValue())
+  if (maskIsAllZeroOrUndef(ConstMask))
     return eraseInstFromFunction(II);
 
   // If the mask is all ones, this is a plain vector store of the 1st argument.
-  if (ConstMask->isAllOnesValue()) {
-    Value *StorePtr = II.getArgOperand(1);
-    Align Alignment = cast<ConstantInt>(II.getArgOperand(2))->getAlignValue();
+  if (maskIsAllOneOrUndef(ConstMask)) {
     StoreInst *S =
         new StoreInst(II.getArgOperand(0), StorePtr, false, Alignment);
     S->copyMetadata(II);
@@ -389,7 +389,7 @@ Instruction *InstCombinerImpl::simplifyMaskedScatter(IntrinsicInst &II) {
     return nullptr;
 
   // If the mask is all zeros, a scatter does nothing.
-  if (ConstMask->isNullValue())
+  if (maskIsAllZeroOrUndef(ConstMask))
     return eraseInstFromFunction(II);
 
   // Vector splat address -> scalar store
diff --git a/llvm/test/Transforms/InstCombine/masked_intrinsics.ll b/llvm/test/Transforms/InstCombine/masked_intrinsics.ll
index 8f7683419a82a..67ab167c189b4 100644
--- a/llvm/test/Transforms/InstCombine/masked_intrinsics.ll
+++ b/llvm/test/Transforms/InstCombine/masked_intrinsics.ll
@@ -16,6 +16,14 @@ define <2 x double> @load_zeromask(ptr %ptr, <2 x double> %passthru)  {
   ret <2 x double> %res
 }
 
+define <2 x double> @load_zero_withpoison_mask(ptr %ptr, <2 x double> %passthru)  {
+; CHECK-LABEL: @load_zero_withpoison_mask(
+; CHECK-NEXT:    ret <2 x double> [[PASSTHRU:%.*]]
+;
+  %res = call <2 x double> @llvm.masked.load.v2f64.p0(ptr %ptr, i32 1, <2 x i1> <i1 0, i1 poison>, <2 x double> %passthru)
+  ret <2 x double> %res
+}
+
 define <2 x double> @load_onemask(ptr %ptr, <2 x double> %passthru)  {
 ; CHECK-LABEL: @load_onemask(
 ; CHECK-NEXT:    [[UNMASKEDLOAD:%.*]] = load <2 x double>, ptr [[PTR:%.*]], align 2
@@ -150,6 +158,14 @@ define void @store_zeromask(ptr %ptr, <2 x double> %val)  {
   ret void
 }
 
+define void @store_poisonmask(ptr %ptr, <2 x double> %val)  {
+; CHECK-LABEL: @store_poisonmask(
+; CHECK-NEXT:    ret void
+;
+  call void @llvm.masked.store.v2f64.p0(<2 x double> %val, ptr %ptr, i32 4, <2 x i1> splat(i1 poison))
+  ret void
+}
+
 define void @store_onemask(ptr %ptr, <2 x double> %val)  {
 ; CHECK-LABEL: @store_onemask(
 ; CHECK-NEXT:    store <2 x double> [[VAL:%.*]], ptr [[PTR:%.*]], align 4
@@ -159,6 +175,15 @@ define void @store_onemask(ptr %ptr, <2 x double> %val)  {
   ret void
 }
 
+define void @store_one_withpoison_mask(ptr %ptr, <2 x double> %val)  {
+; CHECK-LABEL: @store_one_withpoison_mask(
+; CHECK-NEXT:    store <2 x double> [[VAL:%.*]], ptr [[PTR:%.*]], align 4
+; CHECK-NEXT:    ret void
+;
+  call void @llvm.masked.store.v2f64.p0(<2 x double> %val, ptr %ptr, i32 4, <2 x i1> <i1 1, i1 poison>)
+  ret void
+}
+
 define void @store_demandedelts(ptr %ptr, double %val)  {
 ; CHECK-LABEL: @store_demandedelts(
 ; CHECK-NEXT:    [[VALVEC1:%.*]] = insertelement <2 x double> poison, double [[VAL:%.*]], i64 0
@@ -189,6 +214,13 @@ define <2 x double> @gather_zeromask(<2 x ptr> %ptrs, <2 x double> %passthru)  {
   ret <2 x double> %res
 }
 
+define <2 x double> @gather_zero_withpoison_mask(<2 x ptr> %ptrs, <2 x double> %passthru)  {
+; CHECK-LABEL: @gather_zero_withpoison_mask(
+; CHECK-NEXT:    ret <2 x double> [[PASSTHRU:%.*]]
+;
+  %res = call <2 x double> @llvm.masked.gather.v2f64.v2p0(<2 x ptr> %ptrs, i32 4, <2 x i1> <i1 0, i1 poison>, <2 x double> %passthru)
+  ret <2 x double> %res
+}
 
 define <2 x double> @gather_onemask(<2 x ptr> %ptrs, <2 x double> %passthru)  {
 ; CHECK-LABEL: @gather_onemask(
@@ -199,6 +231,15 @@ define <2 x double> @gather_onemask(<2 x ptr> %ptrs, <2 x double> %passthru)  {
   ret <2 x double> %res
 }
 
+define <2 x double> @gather_one_withpoisonmask(<2 x ptr> %ptrs, <2 x double> %passthru)  {
+; CHECK-LABEL: @gather_one_withpoisonmask(
+; CHECK-NEXT:    [[RES:%.*]] = call <2 x double> @llvm.masked.gather.v2f64.v2p0(<2 x ptr> [[PTRS:%.*]], i32 4, <2 x i1> <i1 true, i1 poison>, <2 x double> [[PASSTHRU:%.*]])
+; CHECK-NEXT:    ret <2 x double> [[RES]]
+;
+  %res = call <2 x double> @llvm.masked.gather.v2f64.v2p0(<2 x ptr> %ptrs, i32 4, <2 x i1> <i1 true, i1 poison>, <2 x double> %passthru)
+  ret <2 x double> %res
+}
+
 define <4 x double> @gather_lane2(ptr %base, double %pt)  {
 ; CHECK-LABEL: @gather_lane2(
 ; CHECK-NEXT:    [[PTRS:%.*]] = getelementptr double, ptr [[BASE:%.*]], <4 x i64> <i64 poison, i64 poison, i64 2, i64 poison>
@@ -257,6 +298,23 @@ define void @scatter_zeromask(<2 x ptr> %ptrs, <2 x double> %val)  {
   ret void
 }
 
+define void @scatter_zero_withpoison_mask(<2 x ptr> %ptrs, <2 x double> %val)  {
+; CHECK-LABEL: @scatter_zero_withpoison_mask(
+; CHECK-NEXT:    ret void
+;
+  call void @llvm.masked.scatter.v2f64.v2p0(<2 x double> %val, <2 x ptr> %ptrs, i32 8, <2 x i1> <i1 0, i1 poison>)
+  ret void
+}
+
+define void @scatter_one_withpoison_mask(<2 x ptr> %ptrs, <2 x double> %val)  {
+; CHECK-LABEL: @scatter_one_withpoison_mask(
+; CHECK-NEXT:    call void @llvm.masked.scatter.v2f64.v2p0(<2 x double> [[VAL:%.*]], <2 x ptr> [[PTRS:%.*]], i32 8, <2 x i1> <i1 true, i1 poison>)
+; CHECK-NEXT:    ret void
+;
+  call void @llvm.masked.scatter.v2f64.v2p0(<2 x double> %val, <2 x ptr> %ptrs, i32 8, <2 x i1> <i1 1, i1 poison>)
+  ret void
+}
+
 define void @scatter_demandedelts(ptr %ptr, double %val)  {
 ; CHECK-LABEL: @scatter_demandedelts(
 ; CHECK-NEXT:    [[PTRS:%.*]] = getelementptr double, ptr [[PTR:%.*]], <2 x i64> <i64 0, i64 poison>
diff --git a/llvm/test/Transforms/InstCombine/pr83947.ll b/llvm/test/Transforms/InstCombine/pr83947.ll
index 1906502fdaf23..679230a46d369 100644
--- a/llvm/test/Transforms/InstCombine/pr83947.ll
+++ b/llvm/test/Transforms/InstCombine/pr83947.ll
@@ -24,7 +24,6 @@ define void @masked_scatter2() {
 
 define void @masked_scatter3() {
 ; CHECK-LABEL: define void @masked_scatter3() {
-; CHECK-NEXT:    store i32 0, ptr @c, align 4
 ; CHECK-NEXT:    ret void
 ;
   call void @llvm.masked.scatter.v2i32.v2p0(<2 x i32> zeroinitializer, <2 x ptr> splat (ptr @c), i32 4, <2 x i1> undef)
@@ -50,7 +49,6 @@ define void @masked_scatter5() {
 
 define void @masked_scatter6() {
 ; CHECK-LABEL: define void @masked_scatter6() {
-; CHECK-NEXT:    store i32 0, ptr @c, align 4
 ; CHECK-NEXT:    ret void
 ;
   call void @llvm.masked.scatter.v2i32.v2p0(<2 x i32> zeroinitializer, <2 x ptr> splat (ptr @c), i32 4, <2 x i1> <i1 undef, i1 false>)