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 #pragma weak __truncf = truncf 31 32 #include "libm.h" 33 34 float 35 truncf(float x) { 36 union { 37 unsigned i; 38 float f; 39 } xx; 40 unsigned hx, sx, i; 41 42 xx.f = x; 43 hx = xx.i & ~0x80000000; 44 sx = xx.i & 0x80000000; 45 if (hx < 0x4b000000) { /* |x| < 2^23 */ 46 if (hx < 0x3f800000) /* |x| < 1 */ 47 return (sx ? -0.0F : 0.0F); 48 49 /* chop x at the integer bit */ 50 i = 1 << (0x95 - (hx >> 23)); 51 xx.i &= ~((i << 1) - 1); 52 return (xx.f); 53 } else if (hx < 0x7f800000) /* |x| is integral */ 54 return (x); 55 else 56 #if defined(FPADD_TRAPS_INCOMPLETE_ON_NAN) 57 return (hx > 0x7f800000 ? x * x : x + x); 58 #else 59 return (x + x); 60 #endif 61 } 62