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 * http://www.algor.co.uk 8 * 9 * ######################################################################## 10 * 11 * This program is free software; you can distribute it and/or modify it 12 * under the terms of the GNU General Public License (Version 2) as 13 * published by the Free Software Foundation. 14 * 15 * This program is distributed in the hope it will be useful, but WITHOUT 16 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 17 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 18 * for more details. 19 * 20 * You should have received a copy of the GNU General Public License along 21 * with this program; if not, write to the Free Software Foundation, Inc., 22 * 59 Temple Place - Suite 330, Boston MA 02111-1307, USA. 23 * 24 * ######################################################################## 25 */ 26 27 28 #include "ieee754dp.h" 29 30 ieee754dp ieee754dp_flong(s64 x) 31 { 32 u64 xm; 33 int xe; 34 int xs; 35 36 CLEARCX; 37 38 if (x == 0) 39 return ieee754dp_zero(0); 40 if (x == 1 || x == -1) 41 return ieee754dp_one(x < 0); 42 if (x == 10 || x == -10) 43 return ieee754dp_ten(x < 0); 44 45 xs = (x < 0); 46 if (xs) { 47 if (x == (1ULL << 63)) 48 xm = (1ULL << 63); /* max neg can't be safely negated */ 49 else 50 xm = -x; 51 } else { 52 xm = x; 53 } 54 55 /* normalize */ 56 xe = DP_MBITS + 3; 57 if (xm >> (DP_MBITS + 1 + 3)) { 58 /* shunt out overflow bits */ 59 while (xm >> (DP_MBITS + 1 + 3)) { 60 XDPSRSX1(); 61 } 62 } else { 63 /* normalize in grs extended double precision */ 64 while ((xm >> (DP_MBITS + 3)) == 0) { 65 xm <<= 1; 66 xe--; 67 } 68 } 69 DPNORMRET1(xs, xe, xm, "dp_flong", x); 70 } 71 72 ieee754dp ieee754dp_fulong(u64 u) 73 { 74 if ((s64) u < 0) 75 return ieee754dp_add(ieee754dp_1e63(), 76 ieee754dp_flong(u & ~(1ULL << 63))); 77 return ieee754dp_flong(u); 78 } 79