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/* ===-- fixunsxfti.c - Implement __fixunsxfti -----------------------------===
*
* 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 __fixunsxfti 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: long double is an intel 80 bit floating point type padded with 6 bytes
* tu_int is a 128 bit integral type
* value in long double is representable in tu_int or is negative
*/
/* 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 tu_int
__fixunsxfti(long double a)
{
long_double_bits fb;
fb.f = a;
int e = (fb.u.high.s.low & 0x00007FFF) - 16383;
if (e < 0 || (fb.u.high.s.low & 0x00008000))
return 0;
if ((unsigned)e > sizeof(tu_int) * CHAR_BIT)
return ~(tu_int)0;
tu_int r = fb.u.low.all;
if (e > 63)
r <<= (e - 63);
else
r >>= (63 - e);
return r;
}
#endif /* CRT_HAS_128BIT */
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