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From: "uecker at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug sanitizer/113878] missed optimization with sanitizer and signed integer overflow
Date: Sun, 11 Feb 2024 18:41:09 +0000	[thread overview]
Message-ID: <bug-113878-4-WlS90X6Yj3@http.gcc.gnu.org/bugzilla/> (raw)
In-Reply-To: <bug-113878-4@http.gcc.gnu.org/bugzilla/>

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=113878

--- Comment #4 from uecker at gcc dot gnu.org ---


Would it make sense to add the instrumentation earlier? Then it could be
optimized as usual which may give better results. 

Just adding a test explicitly shows that this works:
https://godbolt.org/z/av15nheTG

Anyway, I am generally not super convinced about how the sanitizers (bloated
library, unfortunate interaction with warnings, missing cases, poor
optimization...) 

I am somewhat tempted to try putting a light-weight instrumentation directly
into the C FE. That does not seem to hard and would avoid all those problems.
But I am probably missing something....  And I have no idea whether something
like this would be acceptable to GCC.

  parent reply	other threads:[~2024-02-11 18:41 UTC|newest]

Thread overview: 10+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2024-02-11 16:46 [Bug c/113878] New: " muecker at gwdg dot de
2024-02-11 16:55 ` [Bug sanitizer/113878] " pinskia at gcc dot gnu.org
2024-02-11 17:43 ` uecker at gcc dot gnu.org
2024-02-11 17:54 ` jakub at gcc dot gnu.org
2024-02-11 18:41 ` uecker at gcc dot gnu.org [this message]
2024-02-11 18:46 ` jakub at gcc dot gnu.org
2024-02-11 19:16 ` uecker at gcc dot gnu.org
2024-02-11 19:28 ` jakub at gcc dot gnu.org
2024-02-11 20:07 ` uecker at gcc dot gnu.org
2024-02-12  9:00 ` rguenth at gcc dot gnu.org

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