[llvm] [TypePromotion] Support positive addition amounts in isSafeWrap. (PR #81690)

[via llvm-commits]

AtariDreams wrote:

Given in how a lot of cases it increases the number of instructions generated as per the tests, I think maybe to restrict this to cases where it will be beneficial, or where the original transform did not work, as opposed to forcing the transformation to be zero extended all the time 

https://github.com/llvm/llvm-project/pull/81690