backend store i64 on target

I’m trying to create new backend. Can anyone help with such question?

In a target there are 32 and 64-bit registers. I’ve made load/store 32-bit values without difficulties. Now i’m doing 64-bit store into memory.

There is a direct 64bit store of register → memory (i represented it in TargetInstructionInfo.td) and wrote lowering for i64 Constant store.

The question is: does it need to do lowering for i64 register to memory store or it should “find” this store in TargetInstructionInfo.td?

Thanks in advance.