1*3cab2bb3Spatrick //===-- fixxfti.c - Implement __fixxfti -----------------------------------===// 2*3cab2bb3Spatrick // 3*3cab2bb3Spatrick // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. 4*3cab2bb3Spatrick // See https://llvm.org/LICENSE.txt for license information. 5*3cab2bb3Spatrick // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception 6*3cab2bb3Spatrick // 7*3cab2bb3Spatrick //===----------------------------------------------------------------------===// 8*3cab2bb3Spatrick // 9*3cab2bb3Spatrick // This file implements __fixxfti for the compiler_rt library. 10*3cab2bb3Spatrick // 11*3cab2bb3Spatrick //===----------------------------------------------------------------------===// 12*3cab2bb3Spatrick 13*3cab2bb3Spatrick #include "int_lib.h" 14*3cab2bb3Spatrick 15*3cab2bb3Spatrick #ifdef CRT_HAS_128BIT 16*3cab2bb3Spatrick 17*3cab2bb3Spatrick // Returns: convert a to a signed long long, rounding toward zero. 18*3cab2bb3Spatrick 19*3cab2bb3Spatrick // Assumption: long double is an intel 80 bit floating point type padded with 6 20*3cab2bb3Spatrick // bytes ti_int is a 128 bit integral type value in long double is representable 21*3cab2bb3Spatrick // in ti_int 22*3cab2bb3Spatrick 23*3cab2bb3Spatrick // gggg gggg gggg gggg gggg gggg gggg gggg | gggg gggg gggg gggg seee eeee eeee 24*3cab2bb3Spatrick // eeee | 1mmm mmmm mmmm mmmm mmmm mmmm mmmm mmmm | mmmm mmmm mmmm mmmm mmmm 25*3cab2bb3Spatrick // mmmm mmmm mmmm 26*3cab2bb3Spatrick __fixxfti(long double a)27*3cab2bb3SpatrickCOMPILER_RT_ABI ti_int __fixxfti(long double a) { 28*3cab2bb3Spatrick const ti_int ti_max = (ti_int)((~(tu_int)0) / 2); 29*3cab2bb3Spatrick const ti_int ti_min = -ti_max - 1; 30*3cab2bb3Spatrick long_double_bits fb; 31*3cab2bb3Spatrick fb.f = a; 32*3cab2bb3Spatrick int e = (fb.u.high.s.low & 0x00007FFF) - 16383; 33*3cab2bb3Spatrick if (e < 0) 34*3cab2bb3Spatrick return 0; 35*3cab2bb3Spatrick ti_int s = -(si_int)((fb.u.high.s.low & 0x00008000) >> 15); 36*3cab2bb3Spatrick ti_int r = fb.u.low.all; 37*3cab2bb3Spatrick if ((unsigned)e >= sizeof(ti_int) * CHAR_BIT) 38*3cab2bb3Spatrick return a > 0 ? ti_max : ti_min; 39*3cab2bb3Spatrick if (e > 63) 40*3cab2bb3Spatrick r <<= (e - 63); 41*3cab2bb3Spatrick else 42*3cab2bb3Spatrick r >>= (63 - e); 43*3cab2bb3Spatrick return (r ^ s) - s; 44*3cab2bb3Spatrick } 45*3cab2bb3Spatrick 46*3cab2bb3Spatrick #endif // CRT_HAS_128BIT 47