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1//===--- lib/builtins/ppc/fixtfti.c - Convert long double->int128 *-C -*---===//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 converting the 128bit IBM/PowerPC long double (double-10// double) data type to a signed 128 bit integer.11//12//===----------------------------------------------------------------------===//13 14#include "../int_math.h"15 16// Convert long double into a signed 128-bit integer.17__int128_t __fixtfti(long double input) {18 19 // If we are trying to convert a NaN, return the NaN bit pattern.20 if (crt_isnan(input)) {21 return ((__uint128_t)0x7FF8000000000000ll) << 64 |22 (__uint128_t)0x0000000000000000ll;23 }24 25 // Note: overflow is an undefined behavior for this conversion.26 // For this reason, overflow is not checked here.27 28 // If the long double is negative, use unsigned conversion from its absolute29 // value.30 if (input < 0.0) {31 __uint128_t result = (__uint128_t)(-input);32 return -((__int128_t)result);33 }34 35 // Otherwise, use unsigned conversion from the input value.36 __uint128_t result = (__uint128_t)input;37 return result;38}39