[PATCH] D19449: Add optimization bisect opt-in calls for ARM passes

[Renato Golin via llvm-commits]

rengolin added a comment.

In http://reviews.llvm.org/D19449#410913, @probinson wrote:

> No no no.  Please do not mix up the two kinds of "users" here.
>  Bisection is for use by compiler developers to track down bugs in the optimizer.
>  Optnone is for use by end-users building their applications who want certain functions not to be optimized, usually as a tactic for improving debug info; this has nothing to do with debugging the compiler.


I assumed the bisection just applying optnone on selected functions (sequentially, randomly, GA, etc) until the function that has the bug manifests itself (if that simple).

In that case, the passes that were not skipped in this patch make a lot of sense, because they're required for correctness. In this case, the change looks good to me.

The fact that final users can *also* use this to disable not only the high-level optimisation passes, but also the low-level ones is an added bonus in my view.

It may prove to be problematic if some of those passes were accidentally triggering correctness code-gen, but that's something that the limited number of cases will tell us in the future. I can't see how one would know of all of them beforehand.

If that's a fair, description of the problem, than LGTM. :)

cheers,
--renato


Repository:
  rL LLVM

http://reviews.llvm.org/D19449