From: Xi Ruoyao <xry111@xry111.site>
To: Alejandro Colomar <alx@kernel.org>, libc-alpha@sourceware.org
Cc: Florian Weimer <fweimer@redhat.com>, Sam James <sam@gentoo.org>,
Richard Biener <rguenth@gcc.gnu.org>,
Andrew Pinski <apinski@marvell.com>
Subject: Re: [RFC v1 0/2] Use -fno-delete-null-pointer-checks to build glibc
Date: Tue, 11 Jul 2023 21:22:41 +0800 [thread overview]
Message-ID: <0867b39d59162428d9092d1ffbc02ec4c0008b47.camel@xry111.site> (raw)
In-Reply-To: <20230711131105.19203-1-alx@kernel.org>
On Tue, 2023-07-11 at 15:11 +0200, Alejandro Colomar wrote:
> Florian reported that there's -fno-delete-null-pointer-checks to tell
> the compiler to not optimize, and only warn about incorrect uses of null
> pointers.
One potential problem is -fno-delete-null-pointer-checks not only
disables optimizations based on __nonnull, but also disables the
optimizations based on other provable non-null pointer values. So maybe
we should run a benchmark to see if there is some severe degradation, if
there is any we may fix it by moving null checks away from hot paths.
--
Xi Ruoyao <xry111@xry111.site>
School of Aerospace Science and Technology, Xidian University
next prev parent reply other threads:[~2023-07-11 13:22 UTC|newest]
Thread overview: 13+ messages / expand[flat|nested] mbox.gz Atom feed top
2023-07-11 13:11 Alejandro Colomar
2023-07-11 13:11 ` [RFC v1 1/2] Makeconfig: Use one line per token Alejandro Colomar
2023-07-11 18:05 ` Adhemerval Zanella Netto
2023-07-11 13:11 ` [RFC v1 2/2] Makeconfig: Compile glibc with -fno-delete-null-pointer-checks Alejandro Colomar
2023-07-11 13:41 ` Florian Weimer
2023-07-11 13:53 ` Siddhesh Poyarekar
2023-07-12 10:56 ` Richard Biener
2023-07-12 12:22 ` Cristian Rodríguez
2023-07-12 12:43 ` Florian Weimer
2023-07-11 13:18 ` [RFC v1 0/2] Use -fno-delete-null-pointer-checks to build glibc Florian Weimer
2023-07-11 13:19 ` Alejandro Colomar
2023-07-11 13:22 ` Xi Ruoyao [this message]
2023-07-11 13:24 ` Alejandro Colomar
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