blob: d9cb3eaf0d91fc000ff0322d9f2abd2512ae445d [file] [log] [blame]
//===-- fixxfti.c - Implement __fixxfti -----------------------------------===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This file implements __fixxfti for the compiler_rt library.
//
//===----------------------------------------------------------------------===//
#if __x86_64
#include "int_lib.h"
// 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.low & 0x00007FFF) - 16383;
if (e < 0)
return 0;
ti_int s = -(si_int)((fb.u.high.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