1 /* IEEE754 floating point arithmetic 2 * double precision: common utilities 3 */ 4 /* 5 * MIPS floating point support 6 * Copyright (C) 1994-2000 Algorithmics Ltd. 7 * 8 * ######################################################################## 9 * 10 * This program is free software; you can distribute it and/or modify it 11 * under the terms of the GNU General Public License (Version 2) as 12 * published by the Free Software Foundation. 13 * 14 * This program is distributed in the hope it will be useful, but WITHOUT 15 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 16 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 17 * for more details. 18 * 19 * You should have received a copy of the GNU General Public License along 20 * with this program; if not, write to the Free Software Foundation, Inc., 21 * 59 Temple Place - Suite 330, Boston MA 02111-1307, USA. 22 * 23 * ######################################################################## 24 */ 25 26 27 #include "ieee754dp.h" 28 29 ieee754dp ieee754dp_flong(s64 x) 30 { 31 u64 xm; 32 int xe; 33 int xs; 34 35 CLEARCX; 36 37 if (x == 0) 38 return ieee754dp_zero(0); 39 if (x == 1 || x == -1) 40 return ieee754dp_one(x < 0); 41 if (x == 10 || x == -10) 42 return ieee754dp_ten(x < 0); 43 44 xs = (x < 0); 45 if (xs) { 46 if (x == (1ULL << 63)) 47 xm = (1ULL << 63); /* max neg can't be safely negated */ 48 else 49 xm = -x; 50 } else { 51 xm = x; 52 } 53 54 /* normalize */ 55 xe = DP_MBITS + 3; 56 if (xm >> (DP_MBITS + 1 + 3)) { 57 /* shunt out overflow bits */ 58 while (xm >> (DP_MBITS + 1 + 3)) { 59 XDPSRSX1(); 60 } 61 } else { 62 /* normalize in grs extended double precision */ 63 while ((xm >> (DP_MBITS + 3)) == 0) { 64 xm <<= 1; 65 xe--; 66 } 67 } 68 DPNORMRET1(xs, xe, xm, "dp_flong", x); 69 } 70 71 ieee754dp ieee754dp_fulong(u64 u) 72 { 73 if ((s64) u < 0) 74 return ieee754dp_add(ieee754dp_1e63(), 75 ieee754dp_flong(u & ~(1ULL << 63))); 76 return ieee754dp_flong(u); 77 } 78