1*25c28e83SPiotr Jasiukajtis /* 2*25c28e83SPiotr Jasiukajtis * CDDL HEADER START 3*25c28e83SPiotr Jasiukajtis * 4*25c28e83SPiotr Jasiukajtis * The contents of this file are subject to the terms of the 5*25c28e83SPiotr Jasiukajtis * Common Development and Distribution License (the "License"). 6*25c28e83SPiotr Jasiukajtis * You may not use this file except in compliance with the License. 7*25c28e83SPiotr Jasiukajtis * 8*25c28e83SPiotr Jasiukajtis * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE 9*25c28e83SPiotr Jasiukajtis * or http://www.opensolaris.org/os/licensing. 10*25c28e83SPiotr Jasiukajtis * See the License for the specific language governing permissions 11*25c28e83SPiotr Jasiukajtis * and limitations under the License. 12*25c28e83SPiotr Jasiukajtis * 13*25c28e83SPiotr Jasiukajtis * When distributing Covered Code, include this CDDL HEADER in each 14*25c28e83SPiotr Jasiukajtis * file and include the License file at usr/src/OPENSOLARIS.LICENSE. 15*25c28e83SPiotr Jasiukajtis * If applicable, add the following below this CDDL HEADER, with the 16*25c28e83SPiotr Jasiukajtis * fields enclosed by brackets "[]" replaced with your own identifying 17*25c28e83SPiotr Jasiukajtis * information: Portions Copyright [yyyy] [name of copyright owner] 18*25c28e83SPiotr Jasiukajtis * 19*25c28e83SPiotr Jasiukajtis * CDDL HEADER END 20*25c28e83SPiotr Jasiukajtis */ 21*25c28e83SPiotr Jasiukajtis 22*25c28e83SPiotr Jasiukajtis /* 23*25c28e83SPiotr Jasiukajtis * Copyright 2011 Nexenta Systems, Inc. All rights reserved. 24*25c28e83SPiotr Jasiukajtis */ 25*25c28e83SPiotr Jasiukajtis /* 26*25c28e83SPiotr Jasiukajtis * Copyright 2006 Sun Microsystems, Inc. All rights reserved. 27*25c28e83SPiotr Jasiukajtis * Use is subject to license terms. 28*25c28e83SPiotr Jasiukajtis */ 29*25c28e83SPiotr Jasiukajtis 30*25c28e83SPiotr Jasiukajtis #pragma weak fmax = __fmax 31*25c28e83SPiotr Jasiukajtis 32*25c28e83SPiotr Jasiukajtis /* 33*25c28e83SPiotr Jasiukajtis * fmax(x,y) returns the larger of x and y. If just one of the 34*25c28e83SPiotr Jasiukajtis * arguments is NaN, fmax returns the other argument. If both 35*25c28e83SPiotr Jasiukajtis * arguments are NaN, fmax returns NaN. 36*25c28e83SPiotr Jasiukajtis * 37*25c28e83SPiotr Jasiukajtis * See fmaxf.c for a discussion of implementation trade-offs. 38*25c28e83SPiotr Jasiukajtis */ 39*25c28e83SPiotr Jasiukajtis 40*25c28e83SPiotr Jasiukajtis #include "libm.h" /* for isgreaterequal macro */ 41*25c28e83SPiotr Jasiukajtis #include <fenv.h> 42*25c28e83SPiotr Jasiukajtis 43*25c28e83SPiotr Jasiukajtis double 44*25c28e83SPiotr Jasiukajtis __fmax(double x, double y) { 45*25c28e83SPiotr Jasiukajtis union { 46*25c28e83SPiotr Jasiukajtis unsigned i[2]; 47*25c28e83SPiotr Jasiukajtis double d; 48*25c28e83SPiotr Jasiukajtis } xx, yy; 49*25c28e83SPiotr Jasiukajtis unsigned s; 50*25c28e83SPiotr Jasiukajtis 51*25c28e83SPiotr Jasiukajtis /* if y is nan, replace it by x */ 52*25c28e83SPiotr Jasiukajtis if (y != y) 53*25c28e83SPiotr Jasiukajtis y = x; 54*25c28e83SPiotr Jasiukajtis 55*25c28e83SPiotr Jasiukajtis /* if x is nan, replace it by y */ 56*25c28e83SPiotr Jasiukajtis if (x != x) 57*25c28e83SPiotr Jasiukajtis x = y; 58*25c28e83SPiotr Jasiukajtis 59*25c28e83SPiotr Jasiukajtis /* At this point, x and y are either both numeric, or both NaN */ 60*25c28e83SPiotr Jasiukajtis if (!isnan(x) && !isgreaterequal(x, y)) 61*25c28e83SPiotr Jasiukajtis x = y; 62*25c28e83SPiotr Jasiukajtis 63*25c28e83SPiotr Jasiukajtis /* 64*25c28e83SPiotr Jasiukajtis * clear the sign of the result if either x or y has its sign clear 65*25c28e83SPiotr Jasiukajtis */ 66*25c28e83SPiotr Jasiukajtis xx.d = x; 67*25c28e83SPiotr Jasiukajtis yy.d = y; 68*25c28e83SPiotr Jasiukajtis #if defined(__sparc) 69*25c28e83SPiotr Jasiukajtis s = ~(xx.i[0] & yy.i[0]) & 0x80000000; 70*25c28e83SPiotr Jasiukajtis xx.i[0] &= ~s; 71*25c28e83SPiotr Jasiukajtis #elif defined(__x86) 72*25c28e83SPiotr Jasiukajtis s = ~(xx.i[1] & yy.i[1]) & 0x80000000; 73*25c28e83SPiotr Jasiukajtis xx.i[1] &= ~s; 74*25c28e83SPiotr Jasiukajtis #else 75*25c28e83SPiotr Jasiukajtis #error Unknown architecture 76*25c28e83SPiotr Jasiukajtis #endif 77*25c28e83SPiotr Jasiukajtis 78*25c28e83SPiotr Jasiukajtis return (xx.d); 79*25c28e83SPiotr Jasiukajtis } 80