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1//===-- fixunsxfsi.c - Implement __fixunsxfsi -----------------------------===//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 __fixunsxfsi for the compiler_rt library.10//11//===----------------------------------------------------------------------===//12 13#if !_ARCH_PPC14 15#include "int_lib.h"16 17// Returns: convert a to a unsigned int, rounding toward zero.18// Negative values all become zero.19 20// Assumption: long double is an intel 80 bit floating point type padded with 621// bytes su_int is a 32 bit integral type value in long double is representable22// in su_int or is negative23 24// gggg gggg gggg gggg gggg gggg gggg gggg | gggg gggg gggg gggg seee eeee eeee25// eeee | 1mmm mmmm mmmm mmmm mmmm mmmm mmmm mmmm | mmmm mmmm mmmm mmmm mmmm26// mmmm mmmm mmmm27 28#if defined(_MSC_VER) && !defined(__clang__)29// MSVC throws a warning about 'uninitialized variable use' here,30// disable it for builds that warn-as-error31#pragma warning(push)32#pragma warning(disable : 4700)33#endif34 35COMPILER_RT_ABI su_int __fixunsxfsi(xf_float a) {36 xf_bits fb;37 fb.f = a;38 int e = (fb.u.high.s.low & 0x00007FFF) - 16383;39 if (e < 0 || (fb.u.high.s.low & 0x00008000))40 return 0;41 if ((unsigned)e > sizeof(su_int) * CHAR_BIT)42 return ~(su_int)0;43 return fb.u.low.s.high >> (31 - e);44}45 46#if defined(_MSC_VER) && !defined(__clang__)47#pragma warning(pop)48#endif49 50#endif // !_ARCH_PPC51