[llvm] [LV] Disable fold tail by masking - when induction vars used outside (PR #81609)

[Niwin Anto via llvm-commits]

niwinanto wrote:

> > Thanks @fhahn for the reviews. Great that you mentioned the Phabricator patch, the test looks good and I copied here. As you suggested, created new pr for the test case with default behavior([niwinanto at 33ec308](https://github.com/niwinanto/llvm-project/commit/33ec3081832a950369ced6d1e8913ac771e689de)) and then updated this pr. However, I messed with the git workflow(I think). Could you please take a look, this is what you intended.
> 
> Yeah that looks good, I'll add a few small additional comments. But best to create a separate PR to just add the test case showing the issue first.

@fhahn I am exactly trying to create a separate PR. https://github.com/niwinanto/llvm-project/pull/2. May be you can help me to figure out what I am doing wrong. I am extremely sorry, getting used to the new workflow.

As you suggested, I created a new commit with different branch and created new PR(for test as mentioned above). For some reason it contain the commit from this PR, which I tried to remove by dropping in interactive re-base and forced push.

Also, addressed feedback regarding the tests. 

https://github.com/llvm/llvm-project/pull/81609