Index: lib/CodeGen/GlobalISel/IRTranslator.cpp
===================================================================
--- lib/CodeGen/GlobalISel/IRTranslator.cpp
+++ lib/CodeGen/GlobalISel/IRTranslator.cpp
@@ -1586,7 +1586,9 @@
   for (auto &VArg : VRegArgs) {
     // If the argument is an unsplit scalar then don't use unpackRegs to avoid
     // creating redundant copies.
-    if (!valueIsSplit(*ArgIt, VMap.getOffsets(*ArgIt))) {
+    // If Offsets for a type is already stored, do not supply it.
+    auto *Offsets = VMap.getOffsets(*ArgIt);
+    if (!valueIsSplit(*ArgIt, Offsets->empty() ? Offsets : nullptr)) {
       auto &VRegs = *VMap.getVRegs(cast<Value>(*ArgIt));
       assert(VRegs.empty() && "VRegs already populated?");
       VRegs.push_back(VArg);