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From: "d_vampile at 163 dot com" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug target/110023] 10% performance drop on important benchmark after r247544.
Date: Tue, 30 May 2023 14:46:40 +0000	[thread overview]
Message-ID: <bug-110023-4-C62NmeSWsW@http.gcc.gnu.org/bugzilla/> (raw)
In-Reply-To: <bug-110023-4@http.gcc.gnu.org/bugzilla/>

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=110023

--- Comment #2 from d_vampile <d_vampile at 163 dot com> ---
(In reply to Andrew Pinski from comment #1)
> This is almost definitely an aarch64 cost model issue ...

Do you mean that the vectorized cost_model of the underlying hardware causes
the policy of not peeling the loop after r247544 to be chosen? ? So why does
loop peeling result in performance improvements?
For the following code, I understand that this is a very standard vectorized
effective loop.
for (j=0; j<STREAM_ARRAY_SIZE; j++)
c[j] = a[j]+b[j];

      parent reply	other threads:[~2023-05-30 14:46 UTC|newest]

Thread overview: 3+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2023-05-29 14:20 [Bug tree-optimization/110023] New: [10.3 Regression] " d_vampile at 163 dot com
2023-05-29 14:31 ` [Bug target/110023] " pinskia at gcc dot gnu.org
2023-05-30 14:46 ` d_vampile at 163 dot com [this message]

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