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
49
50
|
/* 32-bit fixed point signed integer to 128-bit floating point.
Copyright (C) 1997 Free Software Foundation, Inc.
This file is part of the GNU C Library.
The GNU C Library is free software; you can redistribute it and/or
modify it under the terms of the GNU Library General Public License as
published by the Free Software Foundation; either version 2 of the
License, or (at your option) any later version.
The GNU C Library is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
Library General Public License for more details.
You should have received a copy of the GNU Library General Public
License along with the GNU C Library; see the file COPYING.LIB. If not,
write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
Boston, MA 02111-1307, USA. */
#include <quad_float.h>
/* long double _q_itoq(int a);
Convert 'a' to long double.
*/
void
__q_itoq(unsigned int result[4], int a)
{
unsigned rx;
int cs, css;
/* Note that if a==-2^31, then ua will be 2^31. */
unsigned int ua = abs(a);
/* Normalize. */
cs = cntlzw(ua);
ua <<= cs+1;
/* Calculate the exponent, in 4 easy instructions. */
css = 31-cs;
rx = 16383+css << 16 & ~css;
/* Copy the sign bit from 'a'. */
asm ("rlwimi %0,%1,0,0,0": "=r"(rx) : "r"(a), "0"(rx));
/* Put it all together. */
result[2] = result[3] = 0;
asm ("rlwimi %0,%1,16,16,31": "=r"(result[0]) : "r"(ua), "0"(rx));
result[1] = ua << 16;
}
|
