48 lines
1.4 KiB
C
48 lines
1.4 KiB
C
|
/* ===-- fixxfti.c - Implement __fixxfti -----------------------------------===
|
||
|
|
*
|
||
|
|
* 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 __fixxfti for the compiler_rt library.
|
||
|
|
*
|
||
|
|
* ===----------------------------------------------------------------------===
|
||
|
|
*/
|
||
|
|
|
||
|
|
#include "int_lib.h"
|
||
|
|
|
||
|
|
#if __x86_64
|
||
|
|
|
||
|
|
/* 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
|
||
|
|
* su_int is a 32 bit integral type
|
||
|
|
* value in long double is representable in ti_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
|
||
|
|
*/
|
||
|
|
|
||
|
|
ti_int
|
||
|
|
__fixxfti(long double a)
|
||
|
|
{
|
||
|
|
long_double_bits fb;
|
||
|
|
fb.f = a;
|
||
|
|
int e = (fb.u.high.s.low & 0x00007FFF) - 16383;
|
||
|
|
if (e < 0)
|
||
|
|
return 0;
|
||
|
|
ti_int s = -(si_int)((fb.u.high.s.low & 0x00008000) >> 15);
|
||
|
|
ti_int r = fb.u.low.all;
|
||
|
|
if (e > 63)
|
||
|
|
r <<= (e - 63);
|
||
|
|
else
|
||
|
|
r >>= (63 - e);
|
||
|
|
return (r ^ s) - s;
|
||
|
|
}
|
||
|
|
|
||
|
|
#endif /* __x86_64 */
|