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 (the "License"). 6 * You may not use this file except in compliance with the License. 7 * 8 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE 9 * or http://www.opensolaris.org/os/licensing. 10 * See the License for the specific language governing permissions 11 * and limitations under the License. 12 * 13 * When distributing Covered Code, include this CDDL HEADER in each 14 * file and include the License file at usr/src/OPENSOLARIS.LICENSE. 15 * If applicable, add the following below this CDDL HEADER, with the 16 * fields enclosed by brackets "[]" replaced with your own identifying 17 * information: Portions Copyright [yyyy] [name of copyright owner] 18 * 19 * CDDL HEADER END 20 */ 21 /* 22 * Copyright 2011 Nexenta Systems, Inc. All rights reserved. 23 */ 24 /* 25 * Copyright 2005 Sun Microsystems, Inc. All rights reserved. 26 * Use is subject to license terms. 27 */ 28 29 #pragma weak __scalb = scalb 30 #pragma weak _scalb = scalb 31 32 #include "libm.h" 33 34 double 35 scalb(double x, double fn) { 36 int hn, in, n; 37 double z; 38 39 if (isnan(x) || isnan(fn)) 40 return (x * fn); 41 42 in = ((int *)&fn)[HIWORD]; 43 hn = in & ~0x80000000; 44 if (hn == 0x7ff00000) /* fn is inf */ 45 return (_SVID_libm_err(x, fn, 47)); 46 47 /* see if fn is an integer without raising inexact */ 48 if (hn >= 0x43300000) { 49 /* |fn| >= 2^52, so it must be an integer */ 50 n = (in < 0)? -65000 : 65000; 51 } else if (hn < 0x3ff00000) { 52 /* |fn| < 1, so it must be zero or non-integer */ 53 return ((fn == 0.0)? x : (x - x) / (x - x)); 54 } else if (hn < 0x41400000) { 55 /* |fn| < 2^21 */ 56 if ((hn & ((1 << (0x413 - (hn >> 20))) - 1)) 57 | ((int *)&fn)[LOWORD]) 58 return ((x - x) / (x - x)); 59 n = (int)fn; 60 } else { 61 if (((int *)&fn)[LOWORD] & ((1 << (0x433 - (hn >> 20))) - 1)) 62 return ((x - x) / (x - x)); 63 n = (in < 0)? -65000 : 65000; 64 } 65 z = scalbn(x, n); 66 if (z != x) { 67 if (z == 0.0) 68 return (_SVID_libm_err(x, fn, 33)); 69 if (!finite(z)) 70 return (_SVID_libm_err(x, fn, 32)); 71 } 72 return (z); 73 } 74