1 /*-
2 * Copyright (c) 2017 embedded brains GmbH
3 * All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 * 1. Redistributions of source code must retain the above copyright
9 * notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 * notice, this list of conditions and the following disclaimer in the
12 * documentation and/or other materials provided with the distribution.
13 *
14 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
15 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
16 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
17 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
18 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
19 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
20 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
21 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
22 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
23 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
24 * SUCH DAMAGE.
25 */
26
27 #if (__ARM_FP & 0x8) && !defined(__SOFTFP__)
28 #include "fdlibm.h"
29
30 double
sqrt(double x)31 sqrt(double x)
32 {
33 double result;
34 #ifdef _WANT_MATH_ERRNO
35 if (isless(x, 0.0))
36 return __math_invalid(x);
37 #endif
38 #if __ARM_ARCH >= 6
39 __asm__("vsqrt.f64 %P0, %P1" : "=w" (result) : "w" (x));
40 #else
41 /* VFP9 Erratum 760019, see GCC sources "gcc/config/arm/vfp.md" */
42 __asm__("vsqrt.f64 %P0, %P1" : "=&w" (result) : "w" (x));
43 #endif
44 return result;
45 }
46
47 _MATH_ALIAS_d_d(sqrt)
48
49 #else
50 #include "../../math/s_sqrt.c"
51 #endif
52
