[llvm] [DAGTypeLegalize] Legalize ISD::POISON as ISD::UNDEF for Float Type Legalization (PR #135056)

[zhijian lin via llvm-commits]

diggerlin wrote:

> Thanks for looking into this.
> 
> Now that the base PR is reverted, can you pull in the original change from #125883 to reland this?

I think we can revert your revert commit and then land the PR.

https://github.com/llvm/llvm-project/pull/135056