1 /* IEEE754 floating point arithmetic 2 * single precision 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 "ieee754sp.h" 28 29 ieee754sp ieee754sp_fdp(ieee754dp x) 30 { 31 COMPXDP; 32 ieee754sp nan; 33 34 EXPLODEXDP; 35 36 CLEARCX; 37 38 FLUSHXDP; 39 40 switch (xc) { 41 case IEEE754_CLASS_SNAN: 42 SETCX(IEEE754_INVALID_OPERATION); 43 return ieee754sp_nanxcpt(ieee754sp_indef(), "fdp"); 44 case IEEE754_CLASS_QNAN: 45 nan = buildsp(xs, SP_EMAX + 1 + SP_EBIAS, (u32) 46 (xm >> (DP_MBITS - SP_MBITS))); 47 if (!ieee754sp_isnan(nan)) 48 nan = ieee754sp_indef(); 49 return ieee754sp_nanxcpt(nan, "fdp", x); 50 case IEEE754_CLASS_INF: 51 return ieee754sp_inf(xs); 52 case IEEE754_CLASS_ZERO: 53 return ieee754sp_zero(xs); 54 case IEEE754_CLASS_DNORM: 55 /* can't possibly be sp representable */ 56 SETCX(IEEE754_UNDERFLOW); 57 SETCX(IEEE754_INEXACT); 58 if ((ieee754_csr.rm == IEEE754_RU && !xs) || 59 (ieee754_csr.rm == IEEE754_RD && xs)) 60 return ieee754sp_xcpt(ieee754sp_mind(xs), "fdp", x); 61 return ieee754sp_xcpt(ieee754sp_zero(xs), "fdp", x); 62 case IEEE754_CLASS_NORM: 63 break; 64 } 65 66 { 67 u32 rm; 68 69 /* convert from DP_MBITS to SP_MBITS+3 with sticky right shift 70 */ 71 rm = (xm >> (DP_MBITS - (SP_MBITS + 3))) | 72 ((xm << (64 - (DP_MBITS - (SP_MBITS + 3)))) != 0); 73 74 SPNORMRET1(xs, xe, rm, "fdp", x); 75 } 76 } 77