[llvm-branch-commits] [SelectionDAGBuilder] Use address width when lowering ptrtoaddr (PR #139423)

[Alexander Richardson via llvm-branch-commits]

https://github.com/arichardson created https://github.com/llvm/llvm-project/pull/139423

Instead of just deferring to ptrtoint, we should truncate to the index
width and then perform the ZextOrTrunc.