[llvm] [BasicAA] Treat IntToPtr(Argument) similarly to Argument in relation to function-local objects. (PR #134505)

[Nuno Lopes via llvm-commits]

nunoplopes wrote:

You are right that callers cannot guess the address of allocas. So if you get an integer as argument and then do int2ptr that cannot alias with an alloca whose address hasn't escaped & has sufficient provenance (not passed to a function call & not an argument to ptr2int). Just doing icmp is not sufficient for not being able to deduce noalias (only observes address, doesn't give provenance).

https://github.com/llvm/llvm-project/pull/134505