[Bug rtl-optimization/93105] [8/9/10 Regression] Wrong optimization for pointers: provenance of `p + (q1 - q2)` is treated as `q` when the provenance of `p` is unknown

[rguenth at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=93105
Bug 93105 depends on bug 49330, which changed state.

Bug 49330 Summary: Integer arithmetic on addresses optimised with pointer arithmetic rules
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=49330

           What    |Removed                     |Added
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             Status|NEW                         |RESOLVED
         Resolution|---                         |FIXED