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1//===-- fixxfti.c - Implement __fixxfti -----------------------------------===//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 __fixxfti for the compiler_rt library.10//11//===----------------------------------------------------------------------===//12 13#include "int_lib.h"14 15#ifdef CRT_HAS_128BIT16 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 ti_int is a 128 bit integral type value in long double is representable21// in ti_int22 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 27COMPILER_RT_ABI ti_int __fixxfti(xf_float a) {28 const ti_int ti_max = (ti_int)((~(tu_int)0) / 2);29 const ti_int ti_min = -ti_max - 1;30 xf_bits fb;31 fb.f = a;32 int e = (fb.u.high.s.low & 0x00007FFF) - 16383;33 if (e < 0)34 return 0;35 ti_int s = -(si_int)((fb.u.high.s.low & 0x00008000) >> 15);36 ti_int r = fb.u.low.all;37 if ((unsigned)e >= sizeof(ti_int) * CHAR_BIT)38 return a > 0 ? ti_max : ti_min;39 if (e > 63)40 r <<= (e - 63);41 else42 r >>= (63 - e);43 return (r ^ s) - s;44}45 46#endif // CRT_HAS_128BIT47