File: fixxfdi.c

package info (click to toggle)
rustc 1.34.2%2Bdfsg1-1
  • links: PTS, VCS
  • area: main
  • in suites: buster
  • size: 190,620 kB
  • sloc: xml: 133,832; ansic: 22,822; sh: 14,012; asm: 7,935; python: 5,292; cpp: 4,715; awk: 3,426; makefile: 2,601; yacc: 1,618; lex: 350; ruby: 68; pascal: 46
file content (48 lines) | stat: -rw-r--r-- 1,551 bytes parent folder | download | duplicates (12)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
/* ===-- fixxfdi.c - Implement __fixxfdi -----------------------------------===
 *
 *      	       The LLVM Compiler Infrastructure
 *
 * This file is dual licensed under the MIT and the University of Illinois Open
 * Source Licenses. See LICENSE.TXT for details.
 *
 * ===----------------------------------------------------------------------===
 *
 * This file implements __fixxfdi for the compiler_rt library.
 *
 * ===----------------------------------------------------------------------===
 */

#if !_ARCH_PPC

#include "int_lib.h"

/* Returns: convert a to a signed long long, rounding toward zero. */

/* Assumption: long double is an intel 80 bit floating point type padded with 6 bytes
 *             di_int is a 64 bit integral type
 *             value in long double is representable in di_int (no range checking performed)
 */

/* gggg gggg gggg gggg gggg gggg gggg gggg | gggg gggg gggg gggg seee eeee eeee eeee |
 * 1mmm mmmm mmmm mmmm mmmm mmmm mmmm mmmm | mmmm mmmm mmmm mmmm mmmm mmmm mmmm mmmm
 */

COMPILER_RT_ABI di_int
__fixxfdi(long double a)
{
    const di_int di_max = (di_int)((~(du_int)0) / 2);
    const di_int di_min = -di_max - 1;
    long_double_bits fb;
    fb.f = a;
    int e = (fb.u.high.s.low & 0x00007FFF) - 16383;
    if (e < 0)
        return 0;
    if ((unsigned)e >= sizeof(di_int) * CHAR_BIT)
        return a > 0 ? di_max : di_min;
    di_int s = -(si_int)((fb.u.high.s.low & 0x00008000) >> 15);
    di_int r = fb.u.low.all;
    r = (du_int)r >> (63 - e);
    return (r ^ s) - s;
}

#endif /* !_ARCH_PPC */