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From: Hans-Peter Nilsson <hp@axis.com>
To: Jeff Law <jlaw@ventanamicro.com>
CC: <gcc-patches@gcc.gnu.org>
In-Reply-To: <91be1ec3-de85-04cc-0d9f-d3aa69f075dc@ventanamicro.com> (message
	from Jeff Law on Mon, 1 May 2023 07:21:59 -0600)
Subject: Re: [committed] Enable LRA on several ports
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> Date: Mon, 1 May 2023 07:21:59 -0600
> From: Jeff Law <jlaw@ventanamicro.com>

> Spurred by Segher's RFC, I went ahead and tested several ports with LRA 
> enabled.  Not surprisingly, many failed, but a few built their full set 
> of libraries successful and of those a few even ran their testsuites 
> with no regressions.  In fact, enabling LRA fixes a small number of 
> failures on the iq2000 port.
> 
> This patch converts the ports which built their libraries and have test 
> results that are as good as or better than without LRA.

Yeah, I did fix test-suite errors for CRIS with LRA earlier
(see commit logs to the CRIS port this year).

>    There may be 
> minor code quality regressions or there may be minor code quality 
> improvements -- I'm leaving that for the port maintainers to own going 
> forward.

Right; I noticed performance regressions, and didn't want to
commit anything that knowingly degraded performance.  I did
follow the traces but fell into the rabbit-hole of
rtx_costs.  That's the main reason I didn't push a "-mlra"
option or remove the TARGET_LRA_P for CRIS.  (My story and I
stick to it.)

But thanks I guess, it saves me a commit, but (to all!)
please sync check_effective_target_lra for targets you
"convert".  ...oops, it's just CRIS and hppa there (wot, not
converted?)

brgds, H-P