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From: Georgi Marinov <sanmayce@hotmail.com>
To: "gcc@gcc.gnu.org" <gcc@gcc.gnu.org>
Subject: Bad performance (with GCC 11.3.0 - O3) of a small etude in C
Date: Fri, 8 Jul 2022 04:31:31 +0000	[thread overview]
Message-ID: <PAXP251MB0318FCF8821064E384BFC83FC0829@PAXP251MB0318.EURP251.PROD.OUTLOOK.COM> (raw)

Hi,
just wanted to let you know that I found that GCC 11.3.0 -O3 is generating code with many unnecessary jumps (while CLANG 14.0.1 -O3 not) in a small partitioning (for Quicksort) 15 lines of code etude.
In case you are interested I will submit the three disassembly outputs, plus ICL 19.0 -O3, ICL is horrible in that, ICL 15.0 was good but they ruined their legacy.
Generally, GCC is my target compiler, yet, CLANG is better in my usecases. I would like some of your coders to look it up, my wish is GCC to catch up.

Regards

             reply	other threads:[~2022-07-08  4:31 UTC|newest]

Thread overview: 2+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2022-07-08  4:31 Georgi Marinov [this message]
2022-07-08  8:09 ` Martin Liška

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