llvm-project/compiler-rt/lib/fixunsxfdi.c

45 lines
1.3 KiB
C

/* ===-- fixunsxfdi.c - Implement __fixunsxfdi -----------------------------===
*
* The LLVM Compiler Infrastructure
*
* This file is distributed under the University of Illinois Open Source
* License. See LICENSE.TXT for details.
*
* ===----------------------------------------------------------------------===
*
* This file implements __fixunsxfdi for the compiler_rt library.
*
* ===----------------------------------------------------------------------===
*/
#if !_ARCH_PPC
#include "int_lib.h"
/* 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
* du_int is a 64 bit integral type
* value in long double is representable in du_int or is negative
* (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
*/
du_int
__fixunsxfdi(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;
return fb.u.low.all >> (63 - e);
}
#endif