| //===-- fixxfti.c - Implement __fixxfti -----------------------------------===// |
| // |
| // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. |
| // See https://llvm.org/LICENSE.txt for license information. |
| // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception |
| // |
| //===----------------------------------------------------------------------===// |
| // |
| // This file implements __fixxfti for the compiler_rt library. |
| // |
| //===----------------------------------------------------------------------===// |
| |
| #include "int_lib.h" |
| |
| #ifdef CRT_HAS_128BIT |
| |
| // 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 ti_int is a 128 bit integral type value in long double is representable |
| // in ti_int |
| |
| // 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 ti_int __fixxfti(xf_float a) { |
| const ti_int ti_max = (ti_int)((~(tu_int)0) / 2); |
| const ti_int ti_min = -ti_max - 1; |
| xf_bits fb; |
| fb.f = a; |
| int e = (fb.u.high.s.low & 0x00007FFF) - 16383; |
| if (e < 0) |
| return 0; |
| ti_int s = -(si_int)((fb.u.high.s.low & 0x00008000) >> 15); |
| ti_int r = fb.u.low.all; |
| if ((unsigned)e >= sizeof(ti_int) * CHAR_BIT) |
| return a > 0 ? ti_max : ti_min; |
| if (e > 63) |
| r <<= (e - 63); |
| else |
| r >>= (63 - e); |
| return (r ^ s) - s; |
| } |
| |
| #endif // CRT_HAS_128BIT |