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_fint(int 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 == (1 << 31)) 47 xm = ((unsigned) 1 << 31); /* max neg can't be safely negated */ 48 else 49 xm = -x; 50 } else { 51 xm = x; 52 } 53 54 #if 1 55 /* normalize - result can never be inexact or overflow */ 56 xe = DP_MBITS; 57 while ((xm >> DP_MBITS) == 0) { 58 xm <<= 1; 59 xe--; 60 } 61 return builddp(xs, xe + DP_EBIAS, xm & ~DP_HIDDEN_BIT); 62 #else 63 /* normalize */ 64 xe = DP_MBITS + 3; 65 while ((xm >> (DP_MBITS + 3)) == 0) { 66 xm <<= 1; 67 xe--; 68 } 69 DPNORMRET1(xs, xe, xm, "fint", x); 70 #endif 71 } 72 73 ieee754dp ieee754dp_funs(unsigned int u) 74 { 75 if ((int) u < 0) 76 return ieee754dp_add(ieee754dp_1e31(), 77 ieee754dp_fint(u & ~(1 << 31))); 78 return ieee754dp_fint(u); 79 } 80