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From: "bergner at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug c/106755] Incorrect code gen for altivec intrinsics with constant inputs
Date: Fri, 26 Aug 2022 16:35:09 +0000	[thread overview]
Message-ID: <bug-106755-4-bcShWuaNiP@http.gcc.gnu.org/bugzilla/> (raw)
In-Reply-To: <bug-106755-4@http.gcc.gnu.org/bugzilla/>

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=106755

--- Comment #2 from Peter Bergner <bergner at gcc dot gnu.org> ---
So the tests (I've removed all static inline usage and always use -fno-inline)
pass with -O1 and fail with -O2 and -O3.  Looking at all of the optimizations
enabled by -O2 that are not in -O1 and using -fno-* for them, the only option
that allows the tests to pass with -O2 is -fno-strict-aliasing.  That said,
-Wall and -Wstrict-aliasing do not flag any warnings with the code.  I suppose
they could miss some issues in the test case code???

In addition, if I move the vec_muludq() function to its own source file, then
the tests pass with -O2 and -O3.

  parent reply	other threads:[~2022-08-26 16:35 UTC|newest]

Thread overview: 6+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2022-08-26 14:30 [Bug c/106755] New: " munroesj at gcc dot gnu.org
2022-08-26 15:18 ` [Bug c/106755] " bergner at gcc dot gnu.org
2022-08-26 16:35 ` bergner at gcc dot gnu.org [this message]
2022-08-26 17:31 ` [Bug target/106755] " pinskia at gcc dot gnu.org
2022-08-26 18:38 ` bergner at gcc dot gnu.org
2022-08-26 21:01 ` segher at gcc dot gnu.org

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