1353358Sdim//===-- fixxfti.c - Implement __fixxfti -----------------------------------===// 2353358Sdim// 3353358Sdim// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. 4353358Sdim// See https://llvm.org/LICENSE.txt for license information. 5353358Sdim// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception 6353358Sdim// 7353358Sdim//===----------------------------------------------------------------------===// 8353358Sdim// 9353358Sdim// This file implements __fixxfti for the compiler_rt library. 10353358Sdim// 11353358Sdim//===----------------------------------------------------------------------===// 12276789Sdim 13276789Sdim#include "int_lib.h" 14276789Sdim 15276789Sdim#ifdef CRT_HAS_128BIT 16276789Sdim 17353358Sdim// Returns: convert a to a signed long long, rounding toward zero. 18276789Sdim 19353358Sdim// Assumption: long double is an intel 80 bit floating point type padded with 6 20353358Sdim// bytes ti_int is a 128 bit integral type value in long double is representable 21353358Sdim// in ti_int 22276789Sdim 23353358Sdim// gggg gggg gggg gggg gggg gggg gggg gggg | gggg gggg gggg gggg seee eeee eeee 24353358Sdim// eeee | 1mmm mmmm mmmm mmmm mmmm mmmm mmmm mmmm | mmmm mmmm mmmm mmmm mmmm 25353358Sdim// mmmm mmmm mmmm 26276789Sdim 27353358SdimCOMPILER_RT_ABI ti_int __fixxfti(long double a) { 28353358Sdim const ti_int ti_max = (ti_int)((~(tu_int)0) / 2); 29353358Sdim const ti_int ti_min = -ti_max - 1; 30353358Sdim long_double_bits fb; 31353358Sdim fb.f = a; 32353358Sdim int e = (fb.u.high.s.low & 0x00007FFF) - 16383; 33353358Sdim if (e < 0) 34353358Sdim return 0; 35353358Sdim ti_int s = -(si_int)((fb.u.high.s.low & 0x00008000) >> 15); 36353358Sdim ti_int r = fb.u.low.all; 37353358Sdim if ((unsigned)e >= sizeof(ti_int) * CHAR_BIT) 38353358Sdim return a > 0 ? ti_max : ti_min; 39353358Sdim if (e > 63) 40353358Sdim r <<= (e - 63); 41353358Sdim else 42353358Sdim r >>= (63 - e); 43353358Sdim return (r ^ s) - s; 44276789Sdim} 45276789Sdim 46353358Sdim#endif // CRT_HAS_128BIT 47