1/* Truncate long double value.
2 Copyright (C) 1997-2022 Free Software Foundation, Inc.
3 This file is part of the GNU C Library.
4
5 The GNU C Library is free software; you can redistribute it and/or
6 modify it under the terms of the GNU Lesser General Public
7 License as published by the Free Software Foundation; either
8 version 2.1 of the License, or (at your option) any later version.
9
10 The GNU C Library is distributed in the hope that it will be useful,
11 but WITHOUT ANY WARRANTY; without even the implied warranty of
12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
13 Lesser General Public License for more details.
14
15 You should have received a copy of the GNU Lesser General Public
16 License along with the GNU C Library; if not, see
17 <https://www.gnu.org/licenses/>. */
18
19#include <libm-alias-ldouble.h>
20#include <machine/asm.h>
21
22ENTRY(__truncl)
23 fldt 8(%rsp)
24 fnstenv -28(%rsp)
25 movl $0xc00, %edx
26 orl -28(%rsp), %edx
27 movl %edx, -32(%rsp)
28 fldcw -32(%rsp)
29 frndint
30 fnstsw
31 andl $0x1, %eax
32 orl %eax, -24(%rsp)
33 fldenv -28(%rsp)
34 ret
35END(__truncl)
36libm_alias_ldouble (__trunc, trunc)
37

source code of glibc/sysdeps/x86_64/fpu/s_truncl.S