| //===-- fixxfdi.c - Implement __fixxfdi -----------------------------------===// |
| // |
| // 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 __fixxfdi for the compiler_rt library. |
| // |
| //===----------------------------------------------------------------------===// |
| |
| #if !_ARCH_PPC |
| |
| #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 di_int is a 64 bit integral type value in long double is representable |
| // in di_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 |
| |
| #if defined(_MSC_VER) && !defined(__clang__) |
| // MSVC throws a warning about 'uninitialized variable use' here, |
| // disable it for builds that warn-as-error |
| #pragma warning(push) |
| #pragma warning(disable : 4700) |
| #endif |
| |
| COMPILER_RT_ABI di_int __fixxfdi(long double a) { |
| const di_int di_max = (di_int)((~(du_int)0) / 2); |
| const di_int di_min = -di_max - 1; |
| long_double_bits fb; |
| fb.f = a; |
| int e = (fb.u.high.s.low & 0x00007FFF) - 16383; |
| if (e < 0) |
| return 0; |
| if ((unsigned)e >= sizeof(di_int) * CHAR_BIT) |
| return a > 0 ? di_max : di_min; |
| di_int s = -(si_int)((fb.u.high.s.low & 0x00008000) >> 15); |
| di_int r = fb.u.low.all; |
| r = (du_int)r >> (63 - e); |
| return (r ^ s) - s; |
| } |
| |
| #if defined(_MSC_VER) && !defined(__clang__) |
| #pragma warning(pop) |
| #endif |
| |
| #endif // !_ARCH_PPC |