[PATCH] Reorder step != +-1 do code to allow empty latch (PR fortran/52865)

[Tobias Burnus]

Jakub Jelinek wrote:
> As discussed in the PR, this patch performs the decrement of countm1
> before the condition, so that the loop can have empty latch block.
> The testcase from the PR then can be vectorized.
>
> Bootstrapped/regtested on x86_64-linux and i686-linux, ok for trunk?

OK from the FE side.

[I leave it to you and Richard whether you prefer this version or the 
Bool version; quoting from this PR: "Not sure if it is better this way, 
or with doing assignment of the condition result into a bool and using 
it later (as done in the patch for the other PR)." (Other PR = PR 53957.)]

Thanks for the patch!

Tobias

> 2013-01-16  Jakub Jelinek  <jakub@redhat.com>
>
> 	PR fortran/52865
> 	* trans-stmt.c (gfc_trans_do): Put countm1-- before conditional
> 	and use value of countm1 before the decrement in the condition.