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-exception 6 // 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 absolute 29 // 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