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/* ===-- fixunsdfti.c - Implement __fixunsdfti -----------------------------===
*
* 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 __fixunsdfti for the compiler_rt library.
*
* ===----------------------------------------------------------------------===
*/
#include "int_lib.h"
#ifdef CRT_HAS_128BIT
/* Returns: convert a to a unsigned long long, rounding toward zero.
* Negative values all become zero.
*/
/* Assumption: double is a IEEE 64 bit floating point type
* tu_int is a 64 bit integral type
* value in double is representable in tu_int or is negative
* (no range checking performed)
*/
/* seee eeee eeee mmmm mmmm mmmm mmmm mmmm | mmmm mmmm mmmm mmmm mmmm mmmm mmmm mmmm */
COMPILER_RT_ABI tu_int
__fixunsdfti(double a)
{
double_bits fb;
fb.f = a;
int e = ((fb.u.s.high & 0x7FF00000) >> 20) - 1023;
if (e < 0 || (fb.u.s.high & 0x80000000))
return 0;
tu_int r = 0x0010000000000000uLL | (fb.u.all & 0x000FFFFFFFFFFFFFuLL);
if (e > 52)
r <<= (e - 52);
else
r >>= (52 - e);
return r;
}
#endif /* CRT_HAS_128BIT */
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