diff --git a/llvm/include/llvm/Analysis/InstructionSimplify.h b/llvm/include/llvm/Analysis/InstructionSimplify.h
--- a/llvm/include/llvm/Analysis/InstructionSimplify.h
+++ b/llvm/include/llvm/Analysis/InstructionSimplify.h
@@ -319,6 +319,13 @@
 Value *simplifyWithOpReplaced(Value *V, Value *Op, Value *RepOp,
                               const SimplifyQuery &Q, bool AllowRefinement);
 
+/// See if V simplifies when its operand Op is replaced with RepOp. If not,
+/// return null.
+/// AllowRefinement specifies whether the simplification can be a refinement
+/// (e.g. 0 instead of poison), or whether it needs to be strictly identical.
+Value *simplifyWithOpReplaced(Value *V, SmallVectorImpl<Value *> &NewOps,
+                              const SimplifyQuery &Q, bool AllowRefinement);
+
 /// Replace all uses of 'I' with 'SimpleV' and simplify the uses recursively.
 ///
 /// This first performs a normal RAUW of I with SimpleV. It then recursively
diff --git a/llvm/lib/Analysis/InstructionSimplify.cpp b/llvm/lib/Analysis/InstructionSimplify.cpp
--- a/llvm/lib/Analysis/InstructionSimplify.cpp
+++ b/llvm/lib/Analysis/InstructionSimplify.cpp
@@ -3891,28 +3891,10 @@
   return ::SimplifyFCmpInst(Predicate, LHS, RHS, FMF, Q, RecursionLimit);
 }
 
-static Value *simplifyWithOpReplaced(Value *V, Value *Op, Value *RepOp,
+static Value *simplifyWithOpReplaced(Instruction *I, SmallVectorImpl<Value *> &NewOps,
                                      const SimplifyQuery &Q,
                                      bool AllowRefinement,
                                      unsigned MaxRecurse) {
-  assert(!Op->getType()->isVectorTy() && "This is not safe for vectors");
-
-  // Trivial replacement.
-  if (V == Op)
-    return RepOp;
-
-  // We cannot replace a constant, and shouldn't even try.
-  if (isa<Constant>(Op))
-    return nullptr;
-
-  auto *I = dyn_cast<Instruction>(V);
-  if (!I || !is_contained(I->operands(), Op))
-    return nullptr;
-
-  // Replace Op with RepOp in instruction operands.
-  SmallVector<Value *, 8> NewOps(I->getNumOperands());
-  transform(I->operands(), NewOps.begin(),
-            [&](Value *V) { return V == Op ? RepOp : V; });
 
   if (!AllowRefinement) {
     // General InstSimplify functions may refine the result, e.g. by returning
@@ -3950,8 +3932,8 @@
     // simplifies back to %arg. This can only happen because %mul does not
     // dominate %div. To ensure a consistent return value contract, we make sure
     // that this case returns nullptr as well.
-    auto PreventSelfSimplify = [V](Value *Simplified) {
-      return Simplified != V ? Simplified : nullptr;
+    auto PreventSelfSimplify = [I](Value *Simplified) {
+      return Simplified != I ? Simplified : nullptr;
     };
 
     if (auto *B = dyn_cast<BinaryOperator>(I))
@@ -4006,6 +3988,33 @@
   return ConstantFoldInstOperands(I, ConstOps, Q.DL, Q.TLI);
 }
 
+static Value *simplifyWithOpReplaced(Value *V, Value *Op, Value *RepOp,
+                                     const SimplifyQuery &Q,
+                                     bool AllowRefinement,
+                                     unsigned MaxRecurse) {
+  assert(!Op->getType()->isVectorTy() && "This is not safe for vectors");
+
+  // Trivial replacement.
+  if (V == Op)
+    return RepOp;
+
+  // We cannot replace a constant, and shouldn't even try.
+  if (isa<Constant>(Op))
+    return nullptr;
+
+  auto *I = dyn_cast<Instruction>(V);
+  if (!I || !is_contained(I->operands(), Op))
+    return nullptr;
+
+  // Replace Op with RepOp in instruction operands.
+  SmallVector<Value *, 8> NewOps(I->getNumOperands());
+  transform(I->operands(), NewOps.begin(),
+            [&](Value *V) { return V == Op ? RepOp : V; });
+  return ::simplifyWithOpReplaced(I, NewOps, Q, AllowRefinement,
+                                  RecursionLimit);
+}
+
+
 Value *llvm::simplifyWithOpReplaced(Value *V, Value *Op, Value *RepOp,
                                     const SimplifyQuery &Q,
                                     bool AllowRefinement) {
@@ -4013,6 +4022,17 @@
                                   RecursionLimit);
 }
 
+Value *llvm::simplifyWithOpReplaced(Value *V, SmallVectorImpl<Value *> &NewOps,
+                                    const SimplifyQuery &Q,
+                                    bool AllowRefinement) {
+  auto *I = dyn_cast<Instruction>(V);
+  if (!I)
+    return nullptr;
+
+  return ::simplifyWithOpReplaced(I, NewOps, Q, AllowRefinement,
+                                  RecursionLimit);
+}
+
 /// Try to simplify a select instruction when its condition operand is an
 /// integer comparison where one operand of the compare is a constant.
 static Value *simplifySelectBitTest(Value *TrueVal, Value *FalseVal, Value *X,