Summary:
On targets with different pointer sizes, -alignment-from-assumptions could attempt to create SCEV expressions which use different effective SCEV types. The provided test illustrates the issue.
In `getNewAlignment`, AASCEV would be the (only) alloca, which would have an effective SCEV type of i32. But PtrSCEV, the GEP in this case, due to being in the flat/default address space, will have an effective SCEV of i64.
This patch resolves the issue by truncating PtrSCEV to AASCEV's effective type.
Reviewers: hfinkel, jdoerfert
Reviewed By: jdoerfert
Subscribers: jvesely, nhaehnle, hiraditya, javed.absar, kerbowa, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D75471