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From: Jason Mancini <jayrusman@hotmail.com>
To: Jeff Law <law@redhat.com>,
	Segher Boessenkool <segher@kernel.crashing.org>
Cc: Jonathan Wakely <jwakely.gcc@gmail.com>,
	"gcc-help@gcc.gnu.org"	<gcc-help@gcc.gnu.org>
Subject: Re: gcc9 snapshot 20190414 is 30x slower than gcc 6.3
Date: Fri, 19 Apr 2019 02:03:00 -0000	[thread overview]
Message-ID: <BYAPR06MB47108179BE0BC190C65D3A8AAB270@BYAPR06MB4710.namprd06.prod.outlook.com> (raw)
In-Reply-To: <c9351213-6bb8-7ba2-68b7-0a756d07c482@redhat.com>

Working on getting a testcase prepared to file a bug report.  The trimmed down case shows a 6x degradation instead of 45x at -O0, but hopefully that's enough to pinpoint the reason.  (15 vs 85 seconds.)  Seems like some O(n^2) behavior, 15s becomes 90s, but 40s becomes 30m.

I used "gcc -E" to generate the output.  Is that what we're looking for here?  I'm not familiar with *.ii files (or is that the typical extension used for preprocessor output?)

Thanks!

  reply	other threads:[~2019-04-19  2:03 UTC|newest]

Thread overview: 24+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2019-04-17  0:28 Jason Mancini
2019-04-17  2:10 ` Jason Mancini
2019-04-17  2:20   ` Xi Ruoyao
2019-04-17  8:38     ` Jonathan Wakely
2019-04-17  9:07       ` Segher Boessenkool
2019-04-18 16:06       ` Jason Mancini
2019-04-18 19:07         ` Segher Boessenkool
2019-04-18 19:38           ` Jeff Law
2019-04-19  2:03             ` Jason Mancini [this message]
2019-04-22 22:01             ` Jason Mancini
2019-04-22 22:17               ` Jason Mancini
2019-04-23  0:18             ` Jason Mancini
2019-04-23 12:58               ` Jonathan Wakely
2019-04-29 20:33               ` Jason Mancini
2019-05-01 13:31                 ` C11, <stdatomic.h> and atomic pointers Chris Hall
2019-05-01 14:15                   ` Martin Sebor
2019-05-02  7:54                     ` Jonathan Wakely
2019-06-20 11:28                   ` __STDC_NO_THREADS__ and late model gcc/glibc Chris Hall
2019-06-20 12:17                     ` Jonathan Wakely
2019-06-21  9:39                       ` Chris Hall
2019-06-21  9:51                         ` Jonathan Wakely
2020-01-06 15:09                     ` Function returning struct on x86_64 (at least) Chris Hall
2020-01-06 15:19                       ` Marc Glisse
2020-01-07 16:20                         ` Chris Hall

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