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From: Hans-Peter Nilsson <hp@bitrange.com>
To: Jonathan Wakely <jwakely.gcc@gmail.com>
Cc: libstdc++ <libstdc++@gcc.gnu.org>, gcc-patches <gcc-patches@gcc.gnu.org>
Subject: Re: [PATCH] libstdc++ testsuite/std/ranges/iota/max_size_type.cc: Reduce /10 for simulators
Date: Sat, 30 Dec 2023 13:11:24 -0500 (EST)	[thread overview]
Message-ID: <alpine.BSF.2.20.16.2312301301540.72521@arjuna.pair.com> (raw)
In-Reply-To: <CAH6eHdRRowESb6+Dey1i3kYWJoEUfjPxFCW_ccCB01sV6ANE5w@mail.gmail.com>

On Sat, 30 Dec 2023, Jonathan Wakely wrote:

> On Sat, 30 Dec 2023, 01:41 Hans-Peter Nilsson, <hp@bitrange.com> wrote:
> > Or perhaps the cause is known?
> 
> Not to me. It probably is a target codegen bug, since all this test really
> does is emulate a wide integer type using masks and shifts.

If so, a generic code-generator bug.  I've repeated the 5x 
performance regression observation for a native build and 
updated PR113175 (.32 vs 1.73 seconds).  I'll see if I can 
quickly find out whether it's codegen or libstdc++.  I set it 
the PR to the latter for the moment.

> > With this, the test successfully completes in ~34 seconds.
> >
> > Ok to commit?
> >
> 
> Looks OK to me, but Patrick wrote this test so please wait for him to
> confirm. I think this just reduces the number of cases tested, but doesn't
> miss any important edge cases that should be checked.

Understood: holding, but will ping after the usual week.  
Thanks for the review!

brgds, H-P

  reply	other threads:[~2023-12-30 18:11 UTC|newest]

Thread overview: 4+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2023-12-30  1:41 Hans-Peter Nilsson
2023-12-30  9:40 ` Jonathan Wakely
2023-12-30 18:11   ` Hans-Peter Nilsson [this message]
2023-12-31 16:56     ` Hans-Peter Nilsson

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