diff --git a/llvm/lib/IR/IntrinsicInst.cpp b/llvm/lib/IR/IntrinsicInst.cpp
--- a/llvm/lib/IR/IntrinsicInst.cpp
+++ b/llvm/lib/IR/IntrinsicInst.cpp
@@ -135,14 +135,14 @@
   assert(NewValue && "Values must be non-null");
   auto Locations = location_ops();
   auto OldIt = find(Locations, OldValue);
-  assert((OldIt != Locations.end() || DbgAssignAddrReplaced) &&
-         "OldValue must be a current location");
+  if (OldIt == Locations.end()) {
+    assert(DbgAssignAddrReplaced &&
+           "OldValue must be dbg.assign addr if unused in DIArgList");
+    return;
+  }
+
+  assert(OldIt != Locations.end() && "OldValue must be a current location");
   if (!hasArgList()) {
-    // Additional check necessary to avoid unconditionally replacing this
-    // operand when a dbg.assign address is replaced (DbgAssignAddrReplaced is
-    // true).
-    if (OldValue != getVariableLocationOp(0))
-      return;
     Value *NewOperand = isa<MetadataAsValue>(NewValue)
                             ? NewValue
                             : MetadataAsValue::get(
diff --git a/llvm/unittests/IR/DebugInfoTest.cpp b/llvm/unittests/IR/DebugInfoTest.cpp
--- a/llvm/unittests/IR/DebugInfoTest.cpp
+++ b/llvm/unittests/IR/DebugInfoTest.cpp
@@ -370,6 +370,12 @@
   // Replace both.
   TEST_REPLACE(/*Old*/ P2, /*New*/ P1, /*Value*/ P1, /*Address*/ P1);
 
+  // Replace address only, value uses a DIArgList.
+  // Value = {DIArgList(V1)}, Addr = P1.
+  DAI->setRawLocation(DIArgList::get(C, ValueAsMetadata::get(V1)));
+  DAI->setExpression(DIExpression::get(
+      C, {dwarf::DW_OP_LLVM_arg, 0, dwarf::DW_OP_stack_value}));
+  TEST_REPLACE(/*Old*/ P1, /*New*/ P2, /*Value*/ V1, /*Address*/ P2);
 #undef TEST_REPLACE
 }