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 __llrint = llrint 31 #if defined(__sparcv9) || defined(__amd64) 32 #pragma weak lrint = llrint 33 #pragma weak __lrint = llrint 34 #endif 35 36 /* 37 * llrint(x) rounds its argument to the nearest integer according 38 * to the current rounding direction and converts the result to a 39 * 64 bit signed integer. 40 * 41 * If x is NaN, infinite, or so large that the nearest integer would 42 * exceed 64 bits, the invalid operation exception is raised. If x 43 * is not an integer, the inexact exception is raised. 44 */ 45 46 #include "libm.h" 47 48 long long 49 llrint(double x) { 50 /* 51 * Note: The following code works on x86 (in the default rounding 52 * precision mode), but one should just use the fistpll instruction 53 * instead. 54 */ 55 union { 56 unsigned i[2]; 57 double d; 58 } xx, yy; 59 unsigned hx; 60 61 xx.d = x; 62 hx = xx.i[HIWORD] & ~0x80000000; 63 64 if (hx < 0x43300000) { /* |x| < 2^52 */ 65 /* add and subtract a power of two to round x to an integer */ 66 #if defined(__sparc) || defined(__amd64) 67 yy.i[HIWORD] = (xx.i[HIWORD] & 0x80000000) | 0x43300000; 68 #elif defined(__i386) /* !defined(__amd64) */ 69 yy.i[HIWORD] = (xx.i[HIWORD] & 0x80000000) | 0x43e00000; 70 #else 71 #error Unknown architecture 72 #endif 73 yy.i[LOWORD] = 0; 74 x = (x + yy.d) - yy.d; 75 } 76 77 /* now x is nan, inf, or integral */ 78 return ((long long) x); 79 } 80