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1// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.2// See https://llvm.org/LICENSE.txt for license information.3// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception4 5// long double __floatditf(long long x);6// This file implements the PowerPC long long -> long double conversion7 8#include "DD.h"9 10long double __floatditf(int64_t a) {11 12 static const double twop32 = 0x1.0p32;13 static const double twop52 = 0x1.0p52;14 15 doublebits low = {.d = twop52};16 low.x |= a & UINT64_C(0x00000000ffffffff); // 0x1.0p52 + low 32 bits of a.17 18 const double high_addend = (double)((int32_t)(a >> 32)) * twop32 - twop52;19 20 // At this point, we have two double precision numbers21 // high_addend and low.d, and we wish to return their sum22 // as a canonicalized long double:23 24 // This implementation sets the inexact flag spuriously.25 // This could be avoided, but at some substantial cost.26 27 DD result;28 29 result.s.hi = high_addend + low.d;30 result.s.lo = (high_addend - result.s.hi) + low.d;31 32 return result.ld;33}34