diff --git a/llvm/lib/Analysis/InstructionSimplify.cpp b/llvm/lib/Analysis/InstructionSimplify.cpp
index d08be1e55c853..2cb2612bf611e 100644
--- a/llvm/lib/Analysis/InstructionSimplify.cpp
+++ b/llvm/lib/Analysis/InstructionSimplify.cpp
@@ -1095,19 +1095,6 @@ static Value *simplifyDivRem(Instruction::BinaryOps Opcode, Value *Op0,
   if (match(Op1, m_Zero()))
     return PoisonValue::get(Ty);
 
-  // If any element of a constant divisor fixed width vector is zero or undef
-  // the behavior is undefined and we can fold the whole op to poison.
-  auto *Op1C = dyn_cast<Constant>(Op1);
-  auto *VTy = dyn_cast<FixedVectorType>(Ty);
-  if (Op1C && VTy) {
-    unsigned NumElts = VTy->getNumElements();
-    for (unsigned i = 0; i != NumElts; ++i) {
-      Constant *Elt = Op1C->getAggregateElement(i);
-      if (Elt && (Elt->isNullValue() || Q.isUndefValue(Elt)))
-        return PoisonValue::get(Ty);
-    }
-  }
-
   // poison / X -> poison
   // poison % X -> poison
   if (isa<PoisonValue>(Op0))
diff --git a/llvm/lib/IR/ConstantFold.cpp b/llvm/lib/IR/ConstantFold.cpp
index 07dfbc41e79b0..c2780faee403d 100644
--- a/llvm/lib/IR/ConstantFold.cpp
+++ b/llvm/lib/IR/ConstantFold.cpp
@@ -902,11 +902,6 @@ Constant *llvm::ConstantFoldBinaryInstruction(unsigned Opcode, Constant *C1,
         Constant *ExtractIdx = ConstantInt::get(Ty, i);
         Constant *LHS = ConstantExpr::getExtractElement(C1, ExtractIdx);
         Constant *RHS = ConstantExpr::getExtractElement(C2, ExtractIdx);
-
-        // If any element of a divisor vector is zero, the whole op is poison.
-        if (Instruction::isIntDivRem(Opcode) && RHS->isNullValue())
-          return PoisonValue::get(VTy);
-
         Constant *Res = ConstantExpr::isDesirableBinOp(Opcode)
                             ? ConstantExpr::get(Opcode, LHS, RHS)
                             : ConstantFoldBinaryInstruction(Opcode, LHS, RHS);
diff --git a/llvm/lib/Transforms/InstCombine/InstCombineInternal.h b/llvm/lib/Transforms/InstCombine/InstCombineInternal.h
index 7a060cdab2d37..adbd9186c59c5 100644
--- a/llvm/lib/Transforms/InstCombine/InstCombineInternal.h
+++ b/llvm/lib/Transforms/InstCombine/InstCombineInternal.h
@@ -102,6 +102,7 @@ class LLVM_LIBRARY_VISIBILITY InstCombinerImpl final
   Instruction *visitSRem(BinaryOperator &I);
   Instruction *visitFRem(BinaryOperator &I);
   bool simplifyDivRemOfSelectWithZeroOp(BinaryOperator &I);
+  Instruction *commonIDivRemTransforms(BinaryOperator &I);
   Instruction *commonIRemTransforms(BinaryOperator &I);
   Instruction *commonIDivTransforms(BinaryOperator &I);
   Instruction *visitUDiv(BinaryOperator &I);
diff --git a/llvm/lib/Transforms/InstCombine/InstCombineMulDivRem.cpp b/llvm/lib/Transforms/InstCombine/InstCombineMulDivRem.cpp
index b9c165da906da..f85a3c9365135 100644
--- a/llvm/lib/Transforms/InstCombine/InstCombineMulDivRem.cpp
+++ b/llvm/lib/Transforms/InstCombine/InstCombineMulDivRem.cpp
@@ -1158,29 +1158,39 @@ static Value *foldIDivShl(BinaryOperator &I, InstCombiner::BuilderTy &Builder) {
   return nullptr;
 }
 
-/// This function implements the transforms common to both integer division
-/// instructions (udiv and sdiv). It is called by the visitors to those integer
-/// division instructions.
-/// Common integer divide transforms
-Instruction *InstCombinerImpl::commonIDivTransforms(BinaryOperator &I) {
-  if (Instruction *Phi = foldBinopWithPhiOperands(I))
-    return Phi;
-
+/// Common integer divide/remainder transforms
+Instruction *InstCombinerImpl::commonIDivRemTransforms(BinaryOperator &I) {
+  assert(I.isIntDivRem() && "Unexpected instruction");
   Value *Op0 = I.getOperand(0), *Op1 = I.getOperand(1);
-  bool IsSigned = I.getOpcode() == Instruction::SDiv;
+
+  // If any element of a constant divisor fixed width vector is zero or undef
+  // the behavior is undefined and we can fold the whole op to poison.
+  auto *Op1C = dyn_cast<Constant>(Op1);
   Type *Ty = I.getType();
+  auto *VTy = dyn_cast<FixedVectorType>(Ty);
+  if (Op1C && VTy) {
+    unsigned NumElts = VTy->getNumElements();
+    for (unsigned i = 0; i != NumElts; ++i) {
+      Constant *Elt = Op1C->getAggregateElement(i);
+      if (Elt && (Elt->isNullValue() || isa<UndefValue>(Elt)))
+        return replaceInstUsesWith(I, PoisonValue::get(Ty));
+    }
+  }
+
+  if (Instruction *Phi = foldBinopWithPhiOperands(I))
+    return Phi;
 
   // The RHS is known non-zero.
   if (Value *V = simplifyValueKnownNonZero(I.getOperand(1), *this, I))
     return replaceOperand(I, 1, V);
 
-  // Handle cases involving: [su]div X, (select Cond, Y, Z)
-  // This does not apply for fdiv.
+  // Handle cases involving: div/rem X, (select Cond, Y, Z)
   if (simplifyDivRemOfSelectWithZeroOp(I))
     return &I;
 
   // If the divisor is a select-of-constants, try to constant fold all div ops:
-  // C / (select Cond, TrueC, FalseC) --> select Cond, (C / TrueC), (C / FalseC)
+  // C div/rem (select Cond, TrueC, FalseC) --> select Cond, (C div/rem TrueC),
+  // (C div/rem FalseC)
   // TODO: Adapt simplifyDivRemOfSelectWithZeroOp to allow this and other folds.
   if (match(Op0, m_ImmConstant()) &&
       match(Op1, m_Select(m_Value(), m_ImmConstant(), m_ImmConstant()))) {
@@ -1189,6 +1199,21 @@ Instruction *InstCombinerImpl::commonIDivTransforms(BinaryOperator &I) {
       return R;
   }
 
+  return nullptr;
+}
+
+/// This function implements the transforms common to both integer division
+/// instructions (udiv and sdiv). It is called by the visitors to those integer
+/// division instructions.
+/// Common integer divide transforms
+Instruction *InstCombinerImpl::commonIDivTransforms(BinaryOperator &I) {
+  if (Instruction *Res = commonIDivRemTransforms(I))
+    return Res;
+
+  Value *Op0 = I.getOperand(0), *Op1 = I.getOperand(1);
+  bool IsSigned = I.getOpcode() == Instruction::SDiv;
+  Type *Ty = I.getType();
+
   const APInt *C2;
   if (match(Op1, m_APInt(C2))) {
     Value *X;
@@ -2138,29 +2163,11 @@ static Instruction *simplifyIRemMulShl(BinaryOperator &I,
 /// remainder instructions.
 /// Common integer remainder transforms
 Instruction *InstCombinerImpl::commonIRemTransforms(BinaryOperator &I) {
-  if (Instruction *Phi = foldBinopWithPhiOperands(I))
-    return Phi;
+  if (Instruction *Res = commonIDivRemTransforms(I))
+    return Res;
 
   Value *Op0 = I.getOperand(0), *Op1 = I.getOperand(1);
 
-  // The RHS is known non-zero.
-  if (Value *V = simplifyValueKnownNonZero(I.getOperand(1), *this, I))
-    return replaceOperand(I, 1, V);
-
-  // Handle cases involving: rem X, (select Cond, Y, Z)
-  if (simplifyDivRemOfSelectWithZeroOp(I))
-    return &I;
-
-  // If the divisor is a select-of-constants, try to constant fold all rem ops:
-  // C % (select Cond, TrueC, FalseC) --> select Cond, (C % TrueC), (C % FalseC)
-  // TODO: Adapt simplifyDivRemOfSelectWithZeroOp to allow this and other folds.
-  if (match(Op0, m_ImmConstant()) &&
-      match(Op1, m_Select(m_Value(), m_ImmConstant(), m_ImmConstant()))) {
-    if (Instruction *R = FoldOpIntoSelect(I, cast<SelectInst>(Op1),
-                                          /*FoldWithMultiUse*/ true))
-      return R;
-  }
-
   if (isa<Constant>(Op1)) {
     if (Instruction *Op0I = dyn_cast<Instruction>(Op0)) {
       if (SelectInst *SI = dyn_cast<SelectInst>(Op0I)) {
diff --git a/llvm/test/Transforms/InstCombine/div.ll b/llvm/test/Transforms/InstCombine/div.ll
index a91c9bfc91c40..d5d7ce9b7b263 100644
--- a/llvm/test/Transforms/InstCombine/div.ll
+++ b/llvm/test/Transforms/InstCombine/div.ll
@@ -1163,7 +1163,8 @@ define <2 x i8> @sdiv_constant_dividend_select_of_constants_divisor_vec(i1 %b) {
 
 define <2 x i8> @sdiv_constant_dividend_select_of_constants_divisor_vec_ub1(i1 %b) {
 ; CHECK-LABEL: @sdiv_constant_dividend_select_of_constants_divisor_vec_ub1(
-; CHECK-NEXT:    ret <2 x i8> <i8 -10, i8 -10>
+; CHECK-NEXT:    [[R:%.*]] = select i1 [[B:%.*]], <2 x i8> <i8 poison, i8 8>, <2 x i8> <i8 -10, i8 -10>
+; CHECK-NEXT:    ret <2 x i8> [[R]]
 ;
   %s = select i1 %b, <2 x i8> <i8 0, i8 -5>, <2 x i8> <i8 -4, i8 4>
   %r = sdiv <2 x i8> <i8 42, i8 -42>, %s
@@ -1269,7 +1270,8 @@ define <2 x i8> @udiv_constant_dividend_select_of_constants_divisor_vec(i1 %b) {
 
 define <2 x i8> @udiv_constant_dividend_select_of_constants_divisor_vec_ub1(i1 %b) {
 ; CHECK-LABEL: @udiv_constant_dividend_select_of_constants_divisor_vec_ub1(
-; CHECK-NEXT:    ret <2 x i8> <i8 0, i8 53>
+; CHECK-NEXT:    [[R:%.*]] = select i1 [[B:%.*]], <2 x i8> <i8 poison, i8 0>, <2 x i8> <i8 0, i8 53>
+; CHECK-NEXT:    ret <2 x i8> [[R]]
 ;
   %s = select i1 %b, <2 x i8> <i8 0, i8 -5>, <2 x i8> <i8 -4, i8 4>
   %r = udiv <2 x i8> <i8 42, i8 -42>, %s
diff --git a/llvm/test/Transforms/InstCombine/rem.ll b/llvm/test/Transforms/InstCombine/rem.ll
index 4262ef85553b6..4f7687aeaf8bc 100644
--- a/llvm/test/Transforms/InstCombine/rem.ll
+++ b/llvm/test/Transforms/InstCombine/rem.ll
@@ -997,7 +997,8 @@ define <2 x i8> @urem_constant_dividend_select_of_constants_divisor_vec(i1 %b) {
 
 define <2 x i8> @urem_constant_dividend_select_of_constants_divisor_vec_ub1(i1 %b) {
 ; CHECK-LABEL: @urem_constant_dividend_select_of_constants_divisor_vec_ub1(
-; CHECK-NEXT:    ret <2 x i8> <i8 42, i8 2>
+; CHECK-NEXT:    [[R:%.*]] = select i1 [[B:%.*]], <2 x i8> <i8 poison, i8 -42>, <2 x i8> <i8 42, i8 2>
+; CHECK-NEXT:    ret <2 x i8> [[R]]
 ;
   %s = select i1 %b, <2 x i8> <i8 0, i8 -5>, <2 x i8> <i8 -4, i8 4>
   %r = urem <2 x i8> <i8 42, i8 -42>, %s
diff --git a/llvm/test/Transforms/InstCombine/vector-udiv.ll b/llvm/test/Transforms/InstCombine/vector-udiv.ll
index c817b3a1ac5a0..0289b7c70cc4f 100644
--- a/llvm/test/Transforms/InstCombine/vector-udiv.ll
+++ b/llvm/test/Transforms/InstCombine/vector-udiv.ll
@@ -97,3 +97,16 @@ define <4 x i32> @test_v4i32_zext_shl_const_pow2(<4 x i32> %a0, <4 x i16> %a1) {
   %3 = udiv <4 x i32> %a0, %2
   ret <4 x i32> %3
 }
+
+; Make sure we do not simplify udiv <i32 42, i32 -7>, <i32 0, i32 1> to
+; poison when threading udiv over selects
+
+define <2 x i32> @vec_select_udiv_poison(<2 x i1> %x) {
+; CHECK-LABEL: @vec_select_udiv_poison(
+; CHECK-NEXT:    [[DIV:%.*]] = select <2 x i1> [[X:%.*]], <2 x i32> zeroinitializer, <2 x i32> <i32 poison, i32 -7>
+; CHECK-NEXT:    ret <2 x i32> [[DIV]]
+;
+  %sel = select <2 x i1> %x, <2 x i32> <i32 -1, i32 -1>, <2 x i32> <i32 0, i32 1>
+  %div = udiv <2 x i32> <i32 42, i32 -7>, %sel
+  ret <2 x i32> %div
+}
diff --git a/llvm/test/Transforms/InstSimplify/div.ll b/llvm/test/Transforms/InstSimplify/div.ll
index 5ca2e8837b924..e2bc121aee457 100644
--- a/llvm/test/Transforms/InstSimplify/div.ll
+++ b/llvm/test/Transforms/InstSimplify/div.ll
@@ -29,7 +29,7 @@ define <2 x i32> @zero_dividend_vector_poison_elt(<2 x i32> %A) {
 
 define <2 x i8> @sdiv_zero_elt_vec_constfold(<2 x i8> %x) {
 ; CHECK-LABEL: @sdiv_zero_elt_vec_constfold(
-; CHECK-NEXT:    ret <2 x i8> poison
+; CHECK-NEXT:    ret <2 x i8> <i8 poison, i8 0>
 ;
   %div = sdiv <2 x i8> <i8 1, i8 2>, <i8 0, i8 -42>
   ret <2 x i8> %div
@@ -37,7 +37,7 @@ define <2 x i8> @sdiv_zero_elt_vec_constfold(<2 x i8> %x) {
 
 define <2 x i8> @udiv_zero_elt_vec_constfold(<2 x i8> %x) {
 ; CHECK-LABEL: @udiv_zero_elt_vec_constfold(
-; CHECK-NEXT:    ret <2 x i8> poison
+; CHECK-NEXT:    ret <2 x i8> <i8 0, i8 poison>
 ;
   %div = udiv <2 x i8> <i8 1, i8 2>, <i8 42, i8 0>
   ret <2 x i8> %div
@@ -45,7 +45,8 @@ define <2 x i8> @udiv_zero_elt_vec_constfold(<2 x i8> %x) {
 
 define <2 x i8> @sdiv_zero_elt_vec(<2 x i8> %x) {
 ; CHECK-LABEL: @sdiv_zero_elt_vec(
-; CHECK-NEXT:    ret <2 x i8> poison
+; CHECK-NEXT:    [[DIV:%.*]] = sdiv <2 x i8> [[X:%.*]], <i8 -42, i8 0>
+; CHECK-NEXT:    ret <2 x i8> [[DIV]]
 ;
   %div = sdiv <2 x i8> %x, <i8 -42, i8 0>
   ret <2 x i8> %div
@@ -53,7 +54,8 @@ define <2 x i8> @sdiv_zero_elt_vec(<2 x i8> %x) {
 
 define <2 x i8> @udiv_zero_elt_vec(<2 x i8> %x) {
 ; CHECK-LABEL: @udiv_zero_elt_vec(
-; CHECK-NEXT:    ret <2 x i8> poison
+; CHECK-NEXT:    [[DIV:%.*]] = udiv <2 x i8> [[X:%.*]], <i8 0, i8 42>
+; CHECK-NEXT:    ret <2 x i8> [[DIV]]
 ;
   %div = udiv <2 x i8> %x, <i8 0, i8 42>
   ret <2 x i8> %div
@@ -61,7 +63,8 @@ define <2 x i8> @udiv_zero_elt_vec(<2 x i8> %x) {
 
 define <2 x i8> @sdiv_poison_elt_vec(<2 x i8> %x) {
 ; CHECK-LABEL: @sdiv_poison_elt_vec(
-; CHECK-NEXT:    ret <2 x i8> poison
+; CHECK-NEXT:    [[DIV:%.*]] = sdiv <2 x i8> [[X:%.*]], <i8 -42, i8 poison>
+; CHECK-NEXT:    ret <2 x i8> [[DIV]]
 ;
   %div = sdiv <2 x i8> %x, <i8 -42, i8 poison>
   ret <2 x i8> %div
@@ -69,7 +72,8 @@ define <2 x i8> @sdiv_poison_elt_vec(<2 x i8> %x) {
 
 define <2 x i8> @udiv_poison_elt_vec(<2 x i8> %x) {
 ; CHECK-LABEL: @udiv_poison_elt_vec(
-; CHECK-NEXT:    ret <2 x i8> poison
+; CHECK-NEXT:    [[DIV:%.*]] = udiv <2 x i8> [[X:%.*]], <i8 poison, i8 42>
+; CHECK-NEXT:    ret <2 x i8> [[DIV]]
 ;
   %div = udiv <2 x i8> %x, <i8 poison, i8 42>
   ret <2 x i8> %div
diff --git a/llvm/test/Transforms/InstSimplify/rem.ll b/llvm/test/Transforms/InstSimplify/rem.ll
index aceb7cb12185d..5ec803c6d0481 100644
--- a/llvm/test/Transforms/InstSimplify/rem.ll
+++ b/llvm/test/Transforms/InstSimplify/rem.ll
@@ -29,7 +29,7 @@ define <2 x i32> @zero_dividend_vector_poison_elt(<2 x i32> %A) {
 
 define <2 x i8> @srem_zero_elt_vec_constfold(<2 x i8> %x) {
 ; CHECK-LABEL: @srem_zero_elt_vec_constfold(
-; CHECK-NEXT:    ret <2 x i8> poison
+; CHECK-NEXT:    ret <2 x i8> <i8 poison, i8 2>
 ;
   %rem = srem <2 x i8> <i8 1, i8 2>, <i8 0, i8 -42>
   ret <2 x i8> %rem
@@ -37,7 +37,7 @@ define <2 x i8> @srem_zero_elt_vec_constfold(<2 x i8> %x) {
 
 define <2 x i8> @urem_zero_elt_vec_constfold(<2 x i8> %x) {
 ; CHECK-LABEL: @urem_zero_elt_vec_constfold(
-; CHECK-NEXT:    ret <2 x i8> poison
+; CHECK-NEXT:    ret <2 x i8> <i8 1, i8 poison>
 ;
   %rem = urem <2 x i8> <i8 1, i8 2>, <i8 42, i8 0>
   ret <2 x i8> %rem
@@ -45,7 +45,8 @@ define <2 x i8> @urem_zero_elt_vec_constfold(<2 x i8> %x) {
 
 define <2 x i8> @srem_zero_elt_vec(<2 x i8> %x) {
 ; CHECK-LABEL: @srem_zero_elt_vec(
-; CHECK-NEXT:    ret <2 x i8> poison
+; CHECK-NEXT:    [[REM:%.*]] = srem <2 x i8> [[X:%.*]], <i8 -42, i8 0>
+; CHECK-NEXT:    ret <2 x i8> [[REM]]
 ;
   %rem = srem <2 x i8> %x, <i8 -42, i8 0>
   ret <2 x i8> %rem
@@ -53,7 +54,8 @@ define <2 x i8> @srem_zero_elt_vec(<2 x i8> %x) {
 
 define <2 x i8> @urem_zero_elt_vec(<2 x i8> %x) {
 ; CHECK-LABEL: @urem_zero_elt_vec(
-; CHECK-NEXT:    ret <2 x i8> poison
+; CHECK-NEXT:    [[REM:%.*]] = urem <2 x i8> [[X:%.*]], <i8 0, i8 42>
+; CHECK-NEXT:    ret <2 x i8> [[REM]]
 ;
   %rem = urem <2 x i8> %x, <i8 0, i8 42>
   ret <2 x i8> %rem
@@ -61,7 +63,8 @@ define <2 x i8> @urem_zero_elt_vec(<2 x i8> %x) {
 
 define <2 x i8> @srem_undef_elt_vec(<2 x i8> %x) {
 ; CHECK-LABEL: @srem_undef_elt_vec(
-; CHECK-NEXT:    ret <2 x i8> poison
+; CHECK-NEXT:    [[REM:%.*]] = srem <2 x i8> [[X:%.*]], <i8 -42, i8 undef>
+; CHECK-NEXT:    ret <2 x i8> [[REM]]
 ;
   %rem = srem <2 x i8> %x, <i8 -42, i8 undef>
   ret <2 x i8> %rem
@@ -69,7 +72,8 @@ define <2 x i8> @srem_undef_elt_vec(<2 x i8> %x) {
 
 define <2 x i8> @urem_undef_elt_vec(<2 x i8> %x) {
 ; CHECK-LABEL: @urem_undef_elt_vec(
-; CHECK-NEXT:    ret <2 x i8> poison
+; CHECK-NEXT:    [[REM:%.*]] = urem <2 x i8> [[X:%.*]], <i8 undef, i8 42>
+; CHECK-NEXT:    ret <2 x i8> [[REM]]
 ;
   %rem = urem <2 x i8> %x, <i8 undef, i8 42>
   ret <2 x i8> %rem