125c28e83SPiotr Jasiukajtis /* 225c28e83SPiotr Jasiukajtis * CDDL HEADER START 325c28e83SPiotr Jasiukajtis * 425c28e83SPiotr Jasiukajtis * The contents of this file are subject to the terms of the 525c28e83SPiotr Jasiukajtis * Common Development and Distribution License (the "License"). 625c28e83SPiotr Jasiukajtis * You may not use this file except in compliance with the License. 725c28e83SPiotr Jasiukajtis * 825c28e83SPiotr Jasiukajtis * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE 925c28e83SPiotr Jasiukajtis * or http://www.opensolaris.org/os/licensing. 1025c28e83SPiotr Jasiukajtis * See the License for the specific language governing permissions 1125c28e83SPiotr Jasiukajtis * and limitations under the License. 1225c28e83SPiotr Jasiukajtis * 1325c28e83SPiotr Jasiukajtis * When distributing Covered Code, include this CDDL HEADER in each 1425c28e83SPiotr Jasiukajtis * file and include the License file at usr/src/OPENSOLARIS.LICENSE. 1525c28e83SPiotr Jasiukajtis * If applicable, add the following below this CDDL HEADER, with the 1625c28e83SPiotr Jasiukajtis * fields enclosed by brackets "[]" replaced with your own identifying 1725c28e83SPiotr Jasiukajtis * information: Portions Copyright [yyyy] [name of copyright owner] 1825c28e83SPiotr Jasiukajtis * 1925c28e83SPiotr Jasiukajtis * CDDL HEADER END 2025c28e83SPiotr Jasiukajtis */ 2125c28e83SPiotr Jasiukajtis 2225c28e83SPiotr Jasiukajtis /* 2325c28e83SPiotr Jasiukajtis * Copyright 2011 Nexenta Systems, Inc. All rights reserved. 2425c28e83SPiotr Jasiukajtis */ 2525c28e83SPiotr Jasiukajtis /* 2625c28e83SPiotr Jasiukajtis * Copyright 2006 Sun Microsystems, Inc. All rights reserved. 2725c28e83SPiotr Jasiukajtis * Use is subject to license terms. 2825c28e83SPiotr Jasiukajtis */ 2925c28e83SPiotr Jasiukajtis 30*ddc0e0b5SRichard Lowe #pragma weak __ilogbl = ilogbl 3125c28e83SPiotr Jasiukajtis 3225c28e83SPiotr Jasiukajtis #include "libm.h" 3325c28e83SPiotr Jasiukajtis #include "xpg6.h" /* __xpg6 */ 3425c28e83SPiotr Jasiukajtis 3525c28e83SPiotr Jasiukajtis #if defined(__sparc) 3625c28e83SPiotr Jasiukajtis #define ISNORMALL(k, x) (k != 0x7fff) /* assuming k != 0 */ 3725c28e83SPiotr Jasiukajtis #define X86PDNRM(k, x) 3825c28e83SPiotr Jasiukajtis #define XSCALE_OFFSET 0x406f /* 0x3fff + 112 */ 3925c28e83SPiotr Jasiukajtis static const long double xscale = 5192296858534827628530496329220096.0L; 4025c28e83SPiotr Jasiukajtis /* 2^112 */ 4125c28e83SPiotr Jasiukajtis #elif defined(__x86) 4225c28e83SPiotr Jasiukajtis /* 4325c28e83SPiotr Jasiukajtis * if pseudo-denormal, replace by the equivalent normal 4425c28e83SPiotr Jasiukajtis */ 4525c28e83SPiotr Jasiukajtis #define X86PDNRM(k, x) if (k == 0 && (((int *) &x)[1] & 0x80000000) != 0) \ 4625c28e83SPiotr Jasiukajtis ((int *) &x)[2] |= k = 1 4725c28e83SPiotr Jasiukajtis #if defined(HANDLE_UNSUPPORTED) /* assuming k != 0 */ 4825c28e83SPiotr Jasiukajtis #define ISNORMALL(k, x) (k != 0x7fff && (((int *) &x)[1] & 0x80000000) != 0) 4925c28e83SPiotr Jasiukajtis #else 5025c28e83SPiotr Jasiukajtis #define ISNORMALL(k, x) (k != 0x7fff) 5125c28e83SPiotr Jasiukajtis #endif 5225c28e83SPiotr Jasiukajtis #define XSCALE_OFFSET 0x403e /* 0x3fff + 63 */ 5325c28e83SPiotr Jasiukajtis static const long double xscale = 9223372036854775808.0L; /* 2^63 */ 5425c28e83SPiotr Jasiukajtis #endif 5525c28e83SPiotr Jasiukajtis 5625c28e83SPiotr Jasiukajtis static int 5725c28e83SPiotr Jasiukajtis raise_invalid(int v) { /* SUSv3 requires ilogbl(0,+/-Inf,NaN) raise invalid */ 5825c28e83SPiotr Jasiukajtis #ifndef lint 5925c28e83SPiotr Jasiukajtis if ((__xpg6 & _C99SUSv3_ilogb_0InfNaN_raises_invalid) != 0) { 6025c28e83SPiotr Jasiukajtis static const double zero = 0.0; 6125c28e83SPiotr Jasiukajtis volatile double dummy; 6225c28e83SPiotr Jasiukajtis 6325c28e83SPiotr Jasiukajtis dummy = zero / zero; 6425c28e83SPiotr Jasiukajtis } 6525c28e83SPiotr Jasiukajtis #endif 6625c28e83SPiotr Jasiukajtis return (v); 6725c28e83SPiotr Jasiukajtis } 6825c28e83SPiotr Jasiukajtis 6925c28e83SPiotr Jasiukajtis int 7025c28e83SPiotr Jasiukajtis ilogbl(long double x) { 7125c28e83SPiotr Jasiukajtis int k = XBIASED_EXP(x); 7225c28e83SPiotr Jasiukajtis 7325c28e83SPiotr Jasiukajtis X86PDNRM(k, x); 7425c28e83SPiotr Jasiukajtis if (k == 0) { 7525c28e83SPiotr Jasiukajtis if (ISZEROL(x)) 7625c28e83SPiotr Jasiukajtis return (raise_invalid(0x80000001)); 7725c28e83SPiotr Jasiukajtis else { 7825c28e83SPiotr Jasiukajtis x *= xscale; /* scale up by 2^112 or 2^63 */ 7925c28e83SPiotr Jasiukajtis return (XBIASED_EXP(x) - XSCALE_OFFSET); 8025c28e83SPiotr Jasiukajtis } 8125c28e83SPiotr Jasiukajtis } else if (ISNORMALL(k, x)) 8225c28e83SPiotr Jasiukajtis return (k - 0x3fff); 8325c28e83SPiotr Jasiukajtis else 8425c28e83SPiotr Jasiukajtis return (raise_invalid(0x7fffffff)); 8525c28e83SPiotr Jasiukajtis } 86