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 __lrint = lrint 31 32 /* 33 * lrint(x) rounds its argument to the nearest integer according 34 * to the current rounding direction and converts the result to 35 * a 32 bit signed integer. 36 * 37 * If x is NaN, infinite, or so large that the nearest integer 38 * would exceed 32 bits, the invalid operation exception is raised. 39 * If x is not an integer, the inexact exception is raised. 40 */ 41 42 #include <sys/isa_defs.h> /* _ILP32 */ 43 #include "libm.h" 44 45 #if defined(_ILP32) 46 long 47 lrint(double x) { 48 /* 49 * Note: The following code works on x86 (in the default rounding 50 * precision mode), but one should just use the fistpl instruction 51 * instead. 52 */ 53 union { 54 unsigned i[2]; 55 double d; 56 } xx, yy; 57 unsigned hx; 58 59 xx.d = x; 60 hx = xx.i[HIWORD] & ~0x80000000; 61 if (hx < 0x43300000) { /* |x| < 2^52 */ 62 /* add and subtract a power of two to round x to an integer */ 63 #if defined(__sparc) 64 yy.i[HIWORD] = (xx.i[HIWORD] & 0x80000000) | 0x43300000; 65 #elif defined(__x86) 66 yy.i[HIWORD] = (xx.i[HIWORD] & 0x80000000) | 0x43e00000; 67 #else 68 #error Unknown architecture 69 #endif 70 yy.i[LOWORD] = 0; 71 x = (x + yy.d) - yy.d; 72 } 73 74 /* now x is nan, inf, or integral */ 75 return ((long) x); 76 } 77 #else 78 #error Unsupported architecture 79 #endif /* defined(_ILP32) */ 80