1 /* This file is distributed under the University of Illinois Open Source
2 * License. See LICENSE.TXT for details.
5 /* long double __floatditf(long long x); */
6 /* This file implements the PowerPC long long -> long double conversion */
11 long double __floatditf(int64_t a) {
13 static const double twop32 = 0x1.0p32;
14 static const double twop52 = 0x1.0p52;
16 doublebits low = { .d = twop52 };
17 low.x |= a & UINT64_C(0x00000000ffffffff); /* 0x1.0p52 + low 32 bits of a. */
19 const double high_addend = (double)((int32_t)(a >> 32))*twop32 - twop52;
21 /* At this point, we have two double precision numbers
22 * high_addend and low.d, and we wish to return their sum
23 * as a canonicalized long double:
26 /* This implementation sets the inexact flag spuriously.
27 * This could be avoided, but at some substantial cost.
32 result.s.hi = high_addend + low.d;
33 result.s.lo = (high_addend - result.s.hi) + low.d;