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From: "eggert at cs dot ucla.edu" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug middle-end/114347] wrong constant folding when casting __bf16 to int
Date: Fri, 15 Mar 2024 05:19:07 +0000 [thread overview]
Message-ID: <bug-114347-4-tsosn2tyo7@http.gcc.gnu.org/bugzilla/> (raw)
In-Reply-To: <bug-114347-4@http.gcc.gnu.org/bugzilla/>
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=114347
--- Comment #2 from Paul Eggert <eggert at cs dot ucla.edu> ---
(In reply to Andrew Pinski from comment #1)
> I am not so sure that 257.0bf16 gets rounded to 256.
It should get rounded to 256, since 257 has no exact representation in __bf16
and 256 is the closest representable value.
And GCC does this correctly in my experiments. If I compile this:
__bf16 w = 256.0bf16;
__bf16 x = 257.0bf16;
with "gcc -O2 -S", the assembly code says ".value 17280" for both constants.
next prev parent reply other threads:[~2024-03-15 5:19 UTC|newest]
Thread overview: 14+ messages / expand[flat|nested] mbox.gz Atom feed top
2024-03-15 4:55 [Bug c/114347] New: " eggert at cs dot ucla.edu
2024-03-15 5:01 ` [Bug middle-end/114347] " pinskia at gcc dot gnu.org
2024-03-15 5:19 ` eggert at cs dot ucla.edu [this message]
2024-03-15 9:03 ` rguenth at gcc dot gnu.org
2024-03-15 16:58 ` jsm28 at gcc dot gnu.org
2024-03-18 8:03 ` rguenth at gcc dot gnu.org
2024-03-18 8:16 ` jakub at gcc dot gnu.org
2024-03-18 8:53 ` rguenth at gcc dot gnu.org
2024-03-18 9:06 ` jakub at gcc dot gnu.org
2024-03-18 9:08 ` liuhongt at gcc dot gnu.org
2024-03-20 6:02 ` eggert at cs dot ucla.edu
2024-03-20 6:19 ` pinskia at gcc dot gnu.org
2024-03-21 0:48 ` cvs-commit at gcc dot gnu.org
2024-03-25 22:21 ` pinskia at gcc dot gnu.org
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