Re: [PATCH v3 1/4] ree: Default ree pass for O2 and above for rs6000 target.

[Segher Boessenkool <segher@kernel.crashing.org>]

Hi!

The subject should be something like

rs6000: Enable REE pass by default

(and no period at the end).

On Wed, Apr 19, 2023 at 11:23:07PM +0530, Ajit Agarwal wrote:
> This is the patch-1 for improving ree pass for rs6000 target.

It actually just enables it :-)

The mail body should be the proposed commit message.  Nothing more,
nothing less.  If you need (or want) to talk about more things, that is
what a "0/4" message is for (you create that with --cover).  Your patch
messages here do not thread properly, how did you create them?  Things
work fine if you use  git format-patch --thread  :-)

> 	ree: Improve ree pass for rs6000 target.
> 
> 	Add ree pass as a default pass for rs6000 target.
> 
> 	2023-04-19  Ajit Kumar Agarwal  <aagarwa1@linux.ibm.com>

You aren't in MAINTAINERS yet, please fix that first!

> 
> gcc/ChangeLog:
> 
> 	* common/config/rs6000/rs6000-common.cc: Add REE pass as a
> 	default rs6000 target pass for O2 and above.

Why only for -O2?  Only when optimising at all makes sense, people use
-O0 only when they want to skip as many optimisations as possible, maybe
because of compilation time concerns, maybe to avoid an ICE or other
bug.  Isn't REE *always* a good thing, it never degrades code quality?
Or are there situations where it results in worse code?


Segher