[flang-commits] [flang] [flang][CodeGen] add nsw to address calculations (PR #74709)

[Tom Eccles via flang-commits]

tblah wrote:

>  I was talking about setting `nsw` on the do-variable increment that is generated by the loop lowering. 

@vzakhari  Are you sure if this is allowed? do-variables could definitely overflow. Is integer overflow completely undefined in Fortran? I can't find any mention of it in the standard.

https://github.com/llvm/llvm-project/pull/74709