diff --git a/llvm/lib/CodeGen/TargetLoweringBase.cpp b/llvm/lib/CodeGen/TargetLoweringBase.cpp
--- a/llvm/lib/CodeGen/TargetLoweringBase.cpp
+++ b/llvm/lib/CodeGen/TargetLoweringBase.cpp
@@ -614,7 +614,9 @@
             std::end(TargetDAGCombineArray), 0);
 
   for (MVT VT : MVT::fp_valuetypes()) {
-    MVT IntVT = MVT::getIntegerVT(VT.getSizeInBits());
+    TypeSize TS = VT.getSizeInBits();
+    assert(!TS.isScalable() && "Invalid TypeSize");
+    MVT IntVT = MVT::getIntegerVT(VT.getSizeInBits().getFixedSize());
     if (IntVT.isValid()) {
       setOperationAction(ISD::ATOMIC_SWAP, VT, Promote);
       AddPromotedToType(ISD::ATOMIC_SWAP, VT, IntVT);