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Date: Fri, 06 May 2022 09:46:00 +0200
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From: Paul Zimmermann <Paul.Zimmermann@inria.fr>
To: Alexander Monakov <amonakov@ispras.ru>
Cc: gcc-help@gcc.gnu.org, stephane.glondu@inria.fr,
 marc.glisse@inria.fr, sibid@uvic.ca
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 Alexander Monakov on Thu, 5 May 2022 17:56:26 +0300 (MSK))
Subject: Re: slowdown with -std=gnu18 with respect to -std=c99
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       Dear Alexander,

> Good point. Also could you please add latency metrics, I see that your testing
> framework already exposes the '--latency' flag.

here are latency metrics (still on i5-4590):

            | gcc-9 | gcc-10 | gcc-11 |
------------|-------|--------|--------|
 -std=c99   | 70.8  | 70.3   | 70.2   |
 -std=gnu18 | 59.5  | 59.5   | 59.5   |

It thus seems the issue only appears for the reciprocal throughput.

Best regards,
Paul