diff --git a/src/dynarmic/backend/arm64/reg_alloc.cpp b/src/dynarmic/backend/arm64/reg_alloc.cpp
index 0e7126b0..c54c3d10 100644
--- a/src/dynarmic/backend/arm64/reg_alloc.cpp
+++ b/src/dynarmic/backend/arm64/reg_alloc.cpp
@@ -177,6 +177,11 @@ void RegAlloc::PrepareForCall(IR::Inst* result, std::optional<Argument::copyable
 }
 
 void RegAlloc::DefineAsExisting(IR::Inst* inst, Argument& arg) {
+    if (arg.value.IsImmediate()) {
+        inst->ReplaceUsesWith(arg.value);
+        return;
+    }
+
     ASSERT(!ValueLocation(inst));
     auto& info = ValueInfo(arg.value.GetInst());
     info.values.emplace_back(inst);