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 /* 23 * Copyright 2011 Nexenta Systems, Inc. All rights reserved. 24 */ 25 /* 26 * Copyright 2006 Sun Microsystems, Inc. All rights reserved. 27 * Use is subject to license terms. 28 */ 29 30 #if defined(ELFOBJ) 31 #pragma weak roundf = __roundf 32 #endif 33 34 #include "libm.h" 35 36 float 37 roundf(float x) { 38 union { 39 unsigned i; 40 float f; 41 } xx; 42 unsigned hx, sx, i; 43 44 xx.f = x; 45 hx = xx.i & ~0x80000000; 46 sx = xx.i & 0x80000000; 47 if (hx < 0x4b000000) { /* |x| < 2^23 */ 48 if (hx < 0x3f800000) { /* |x| < 1 */ 49 if (hx >= 0x3f000000) 50 return (sx ? -1.0F : 1.0F); 51 return (sx ? -0.0F : 0.0F); 52 } 53 54 /* round x at the integer bit */ 55 i = 1 << (0x95 - (hx >> 23)); 56 xx.i = (xx.i + i) & ~((i << 1) - 1); 57 return (xx.f); 58 } else if (hx < 0x7f800000) /* |x| is integral */ 59 return (x); 60 else 61 #if defined(FPADD_TRAPS_INCOMPLETE_ON_NAN) 62 return (hx > 0x7f800000 ? x * x : x + x); 63 #else 64 return (x + x); 65 #endif 66 } 67