1 /* 2 * CDDL HEADER START 3 * 4 * The contents of this file are subject to the terms of the 5 * Common Development and Distribution License, Version 1.0 only 6 * (the "License"). You may not use this file except in compliance 7 * with the License. 8 * 9 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE 10 * or http://www.opensolaris.org/os/licensing. 11 * See the License for the specific language governing permissions 12 * and limitations under the License. 13 * 14 * When distributing Covered Code, include this CDDL HEADER in each 15 * file and include the License file at usr/src/OPENSOLARIS.LICENSE. 16 * If applicable, add the following below this CDDL HEADER, with the 17 * fields enclosed by brackets "[]" replaced with your own identifying 18 * information: Portions Copyright [yyyy] [name of copyright owner] 19 * 20 * CDDL HEADER END 21 */ 22 /* 23 * Copyright (c) 1994-1997, by Sun Microsystems, Inc. 24 * All rights reserved. 25 */ 26 27 #include "quad.h" 28 29 /* 30 * _Q_lltoq(x) returns (long double)x. 31 */ 32 union longdouble _Q_lltoq(long long x)33_Q_lltoq(long long x) 34 { 35 union longdouble z; 36 unsigned int s, e; 37 38 /* extract the sign */ 39 s = 0; 40 if (x < 0) { 41 if ((unsigned long long) x == 0x8000000000000000ull) { 42 /* largest negative 64 bit int */ 43 Z.l.msw = 0xc03e0000; 44 Z.l.frac2 = Z.l.frac3 = Z.l.frac4 = 0; 45 QUAD_RETURN(Z); 46 } 47 x = -x; 48 s = 0x80000000; 49 } else if (x == 0) { 50 Z.l.msw = Z.l.frac2 = Z.l.frac3 = Z.l.frac4 = 0; 51 QUAD_RETURN(Z); 52 } 53 54 /* find the most significant bit */ 55 for (e = 62; (x & (1ll << e)) == 0; e--) 56 ; 57 58 if (e > 48) { 59 Z.l.msw = ((unsigned long long) x >> (e - 16)) & 0xffff; 60 Z.l.frac2 = (unsigned long long) x >> (e - 48); 61 Z.l.frac3 = (unsigned long long) x << (80 - e); 62 } else if (e > 16) { 63 Z.l.msw = ((unsigned long long) x >> (e - 16)) & 0xffff; 64 Z.l.frac2 = (unsigned long long) x << (48 - e); 65 Z.l.frac3 = 0; 66 } else { 67 Z.l.msw = ((unsigned long long) x << (16 - e)) & 0xffff; 68 Z.l.frac2 = Z.l.frac3 = 0; 69 } 70 Z.l.frac4 = 0; 71 Z.l.msw |= s | ((e + 0x3fff) << 16); 72 QUAD_RETURN(Z); 73 } 74