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/*
* CDDL HEADER START
*
* The contents of this file are subject to the terms of the
* Common Development and Distribution License (the "License").
* You may not use this file except in compliance with the License.
*
* You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
* or http://www.opensolaris.org/os/licensing.
* See the License for the specific language governing permissions
* and limitations under the License.
*
* When distributing Covered Code, include this CDDL HEADER in each
* file and include the License file at usr/src/OPENSOLARIS.LICENSE.
* If applicable, add the following below this CDDL HEADER, with the
* fields enclosed by brackets "[]" replaced with your own identifying
* information: Portions Copyright [yyyy] [name of copyright owner]
*
* CDDL HEADER END
*/
/*
* Copyright 2011 Nexenta Systems, Inc. All rights reserved.
*/
/*
* Copyright 2006 Sun Microsystems, Inc. All rights reserved.
* Use is subject to license terms.
*/
#pragma weak __lrint = lrint
/*
* lrint(x) rounds its argument to the nearest integer according
* to the current rounding direction and converts the result to
* a 32 bit signed integer.
*
* If x is NaN, infinite, or so large that the nearest integer
* would exceed 32 bits, the invalid operation exception is raised.
* If x is not an integer, the inexact exception is raised.
*/
#include <sys/isa_defs.h> /* _ILP32 */
#include "libm.h"
#if defined(_ILP32)
long
lrint(double x) {
/*
* Note: The following code works on x86 (in the default rounding
* precision mode), but one should just use the fistpl instruction
* instead.
*/
union {
unsigned i[2];
double d;
} xx, yy;
unsigned hx;
xx.d = x;
hx = xx.i[HIWORD] & ~0x80000000;
if (hx < 0x43300000) { /* |x| < 2^52 */
/* add and subtract a power of two to round x to an integer */
#if defined(__sparc)
yy.i[HIWORD] = (xx.i[HIWORD] & 0x80000000) | 0x43300000;
#elif defined(__x86)
yy.i[HIWORD] = (xx.i[HIWORD] & 0x80000000) | 0x43e00000;
#else
#error Unknown architecture
#endif
yy.i[LOWORD] = 0;
x = (x + yy.d) - yy.d;
}
/* now x is nan, inf, or integral */
return ((long) x);
}
#else
#error Unsupported architecture
#endif /* defined(_ILP32) */
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