[llvm-dev] OptBisect implementation for new pass manager

[Fedor Sergeev via llvm-dev]

I would really like to separate OptBisect and New-PM-by-default 
discussions! :)

regards,
   Fedor.

On 09/26/2018 09:13 PM, David Greene wrote:
> I'm concerned about codegen.  If Codegen is not yet ready for the new
> PM, should the new PM really become default?  I would at least like to
> see a plan of how Codegen is going to migrate before the new PM becomes
> default.  Codegen pass pipelines have been wonky ever since I started
> working with LLVM and it would be nice to get that cleaned up.
>
>                              -David
>
> Philip Pfaffe <philip.pfaffe at gmail.com> writes:
>
>> Well, I think we don't have a clear idea about new-PM codegen should
>> work in general. Is this really something that concerns us right now?
>>
>> Philip
>>
>> On Wed, Sep 26, 2018 at 7:54 PM Friedman, Eli
>> <efriedma at codeaurora.org> wrote:
>>
>>      On 9/26/2018 10:47 AM, Philip Pfaffe via llvm-dev wrote:
>>      > Hi Fedor,
>>      >
>>      > can you make an example where a pass actually needs to opt-out?
>>      > Because IMO, bisect should quite literally to DebugCounter-style
>>      skip
>>      > every step in every ::run method's loop. Passes should not even
>>      be
>>      > concerned with this.
>>      
>>      This isn't so much an issue for the optimization pipeline, but
>>      code
>>      generation involves some passes which are mandatory (e.g. isel).
>>      
>>      -Eli
>>      
>>      --
>>      Employee of Qualcomm Innovation Center, Inc.
>>      Qualcomm Innovation Center, Inc. is a member of Code Aurora Forum,
>>      a Linux Foundation Collaborative Project
>>