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// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
// long double __floatditf(long long x);
// This file implements the PowerPC long long -> long double conversion
#include "DD.h"
#include <stdint.h>
long double __floatditf(int64_t a) {
static const double twop32 = 0x1.0p32;
static const double twop52 = 0x1.0p52;
doublebits low = { .d = twop52 };
low.x |= a & UINT64_C(0x00000000ffffffff); // 0x1.0p52 + low 32 bits of a.
const double high_addend = (double)((int32_t)(a >> 32))*twop32 - twop52;
// At this point, we have two double precision numbers
// high_addend and low.d, and we wish to return their sum
// as a canonicalized long double:
// This implementation sets the inexact flag spuriously.
// This could be avoided, but at some substantial cost.
DD result;
result.hi = high_addend + low.d;
result.lo = (high_addend - result.hi) + low.d;
return result.ld;
}
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