[llvm] [CodeGenPrepare] Make sure that `AddOffset` is also a loop invariant (PR #150625)

[Florian Hahn via llvm-commits]

================
@@ -1065,3 +1065,21 @@ for.body:
   %exitcond.not = icmp eq i32 %inc, %N
   br i1 %exitcond.not, label %for.cond.cleanup, label %for.body
 }
+
+define i64 @pr150611_add_offset_is_not_loop_invariant(i1 %cond) {
+entry:
----------------
fhahn wrote:

Would be good to generate check lines here?

https://github.com/llvm/llvm-project/pull/150625