1 /* Copyright (C) 2000-2021 Free Software Foundation, Inc.
2 This file is part of the GNU C Library.
3
4 The GNU C Library is free software; you can redistribute it and/or
5 modify it under the terms of the GNU Lesser General Public
6 License as published by the Free Software Foundation; either
7 version 2.1 of the License, or (at your option) any later version.
8
9 The GNU C Library is distributed in the hope that it will be useful,
10 but WITHOUT ANY WARRANTY; without even the implied warranty of
11 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
12 Lesser General Public License for more details.
13
14 You should have received a copy of the GNU Lesser General Public
15 License along with the GNU C Library. If not, see
16 <https://www.gnu.org/licenses/>. */
17
18 #define NO_MATH_REDIRECT
19 #include <math.h>
20 #include <libm-alias-float.h>
21
22
23 float
__rintf(float x)24 __rintf (float x)
25 {
26 if (isnanf (x))
27 return x + x;
28
29 if (isless (fabsf (x), 16777216.0f)) /* 1 << FLT_MANT_DIG */
30 {
31 /* Note that Alpha S_Floating is stored in registers in a
32 restricted T_Floating format, so we don't even need to
33 convert back to S_Floating in the end. The initial
34 conversion to T_Floating is needed to handle denormals. */
35
36 float tmp1, tmp2, new_x;
37
38 __asm ("cvtst/s %3,%2\n\t"
39 "cvttq/svid %2,%1\n\t"
40 "cvtqt/d %1,%0\n\t"
41 : "=f"(new_x), "=&f"(tmp1), "=&f"(tmp2)
42 : "f"(x));
43
44 /* rint(-0.1) == -0, and in general we'll always have the same
45 sign as our input. */
46 x = copysignf(new_x, x);
47 }
48 return x;
49 }
50
51 libm_alias_float (__rint, rint)
52