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