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From: "chfast at gmail dot com" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug target/96793] __builtin_floor produces wrong result when
 rounding direction is FE_DOWNWARD
Date: Fri, 28 Aug 2020 14:31:37 +0000
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https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D96793

--- Comment #16 from Pawe=C5=82 Bylica <chfast at gmail dot com> ---
I have checked the glibc implementation of floorf().
Source here:
https://sourceware.org/git/?p=3Dglibc.git;a=3Dblob;f=3Dsysdeps/ieee754/flt-=
32/s_floorf.c;h=3Dda6c6dfa8ae86129e74dffff2e4391fac3a3c2ec;hb=3DHEAD

- It has variant for SSE 4.1 using ROUNDSS 9 - all good here.
- Otherwise it either uses __builtin_floorf() (so bug here),
- or generic implementation based on bit manipulations (so should be roundi=
ng
direction independent).=