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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"
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.s.hi = high_addend + low.d;
result.s.lo = (high_addend - result.s.hi) + low.d;
return result.ld;
}
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