[llvm] [SCCP] Support constant structure in PhiNode (PR #163713)

[Yingwei Zheng via llvm-commits]

dtcxzyw wrote:

> Also, I just got commit bit yesterday from LLVM but haven't received the invitation link.
Can I merge this patch myself once I get the link?

Sure :)

https://github.com/llvm/llvm-project/pull/163713