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1//===-- fixxfdi.c - Implement __fixxfdi -----------------------------------===//2//3// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.4// See https://llvm.org/LICENSE.txt for license information.5// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception6//7//===----------------------------------------------------------------------===//8//9// This file implements __fixxfdi for the compiler_rt library.10//11//===----------------------------------------------------------------------===//12 13#if !_ARCH_PPC14 15#include "int_lib.h"16 17// Returns: convert a to a signed long long, rounding toward zero.18 19// Assumption: long double is an intel 80 bit floating point type padded with 620// bytes di_int is a 64 bit integral type value in long double is representable21// in di_int (no range checking performed)22 23// gggg gggg gggg gggg gggg gggg gggg gggg | gggg gggg gggg gggg seee eeee eeee24// eeee | 1mmm mmmm mmmm mmmm mmmm mmmm mmmm mmmm | mmmm mmmm mmmm mmmm mmmm25// mmmm mmmm mmmm26 27#if defined(_MSC_VER) && !defined(__clang__)28// MSVC throws a warning about 'uninitialized variable use' here,29// disable it for builds that warn-as-error30#pragma warning(push)31#pragma warning(disable : 4700)32#endif33 34COMPILER_RT_ABI di_int __fixxfdi(xf_float a) {35 const di_int di_max = (di_int)((~(du_int)0) / 2);36 const di_int di_min = -di_max - 1;37 xf_bits fb;38 fb.f = a;39 int e = (fb.u.high.s.low & 0x00007FFF) - 16383;40 if (e < 0)41 return 0;42 if ((unsigned)e >= sizeof(di_int) * CHAR_BIT)43 return a > 0 ? di_max : di_min;44 di_int s = -(si_int)((fb.u.high.s.low & 0x00008000) >> 15);45 di_int r = fb.u.low.all;46 r = (du_int)r >> (63 - e);47 return (r ^ s) - s;48}49 50#if defined(_MSC_VER) && !defined(__clang__)51#pragma warning(pop)52#endif53 54#endif // !_ARCH_PPC55