Re: [RFA] New pass for sign/zero extension elimination

[Jeff Law <jeffreyalaw@gmail.com>]

On 11/30/23 18:08, Hans-Peter Nilsson wrote:
>> Date: Sun, 19 Nov 2023 17:47:56 -0700
>> From: Jeff Law <jlaw@ventanamicro.com>
> 
>> Locally we have had this enabled at -O1 and above to encourage testing,
>> but I'm thinking that for the trunk enabling at -O2 and above is the
>> right thing to do.
> 
> Yes.
> 
>> Thoughts, comments, recommendations?
> 
> Sounds great!
> 
> It'd be nice if its framework can be re-used for
> target-specific passes, doing quirky sign- or zero-extend-
> related optimizations (those that are not just sign- or
> zero-extend removal).  Perhaps most of those opportunities
> can be implemented as target hooks in this pass.  Definitely
> not asking for a change, just imagining future improvements.
> 
> Also, I haven't followed the thread and its branches, just
> offering a word encouragement.
What kind of quirky target things did you have in mind?  If there's 
overlap with things we need I might be able to find someone to take it 
on.  Or might be able to suggest how they can be handled.


jeff