1/* ===-- fixunsxfdi.c - Implement __fixunsxfdi -----------------------------===
2 *
3 *                     The LLVM Compiler Infrastructure
4 *
5 * This file is dual licensed under the MIT and the University of Illinois Open
6 * Source Licenses. See LICENSE.TXT for details.
7 *
8 * ===----------------------------------------------------------------------===
9 *
10 * This file implements __fixunsxfdi for the compiler_rt library.
11 *
12 * ===----------------------------------------------------------------------===
13 */
14
15#if !_ARCH_PPC
16
17#include "int_lib.h"
18
19/* Returns: convert a to a unsigned long long, rounding toward zero.
20 *          Negative values all become zero.
21 */
22
23/* Assumption: long double is an intel 80 bit floating point type padded with 6 bytes
24 *             du_int is a 64 bit integral type
25 *             value in long double is representable in du_int or is negative
26 *                 (no range checking performed)
27 */
28
29/* gggg gggg gggg gggg gggg gggg gggg gggg | gggg gggg gggg gggg seee eeee eeee eeee |
30 * 1mmm mmmm mmmm mmmm mmmm mmmm mmmm mmmm | mmmm mmmm mmmm mmmm mmmm mmmm mmmm mmmm
31 */
32
33COMPILER_RT_ABI du_int
34__fixunsxfdi(long double a)
35{
36    long_double_bits fb;
37    fb.u.high.s.low = 0;
38    fb.f = a;
39    int e = (fb.u.high.s.low & 0x00007FFF) - 16383;
40    if (e < 0 || (fb.u.high.s.low & 0x00008000))
41        return 0;
42    if ((unsigned)e > sizeof(du_int) * CHAR_BIT)
43        return ~(du_int)0;
44    return fb.u.low.all >> (63 - e);
45}
46
47#endif
48