/*
* 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 __nexttowardl = nexttowardl
#include "libm.h"
#include <float.h> /* LDBL_MAX, LDBL_MIN */
#if defined(__sparc)
#define n0 0
#define n1 1
#define n2 2
#define n3 3
#define X86PDNRM1(x)
#define INC(px) { \
if (++px[n3] == 0) \
if (++px[n2] == 0) \
if (++px[n1] == 0) \
++px[n0]; \
}
#define DEC(px) { \
if (--px[n3] == 0xffffffff) \
if (--px[n2] == 0xffffffff) \
if (--px[n1] == 0xffffffff) \
--px[n0]; \
}
#elif defined(__x86)
#define n0 2
#define n1 1
#define n2 0
#define n3 0
/*
* if pseudo-denormal, replace by the equivalent normal
*/
#define X86PDNRM1(x) if (XBIASED_EXP(x) == 0 && (((int *) &x)[1] & \
0x80000000) != 0) \
((int *) &x)[2] |= 1
#define INC(px) { \
if (++px[n2] == 0) \
if ((++px[n1] & ~0x80000000) == 0) \
px[n1] = 0x80000000, ++px[n0]; \
}
#define DEC(px) { \
if (--px[n2] == 0xffffffff) \
if (--px[n1] == 0x7fffffff) \
if ((--px[n0] & 0x7fff) != 0) \
px[n1] |= 0x80000000; \
}
#endif
long double
nexttowardl(long double x, long double y) {
int *px = (int *) &x;
int *py = (int *) &y;
if (x == y)
return (y); /* C99 requirement */
if (x != x || y != y)
return (x * y);
if (ISZEROL(x)) { /* x == 0.0 */
px[n0] = py[n0] & XSGNMSK;
px[n1] = px[n2] = 0;
px[n3] = 1;
} else {
X86PDNRM1(x);
if ((px[n0] & XSGNMSK) == 0) { /* x > 0.0 */
if (x > y) /* x > y */
DEC(px)
else
INC(px)
} else {
if (x < y) /* x < y */
DEC(px)
else
INC(px)
}
}
#ifndef lint
{
volatile long double dummy;
int k = XBIASED_EXP(x);
if (k == 0)
dummy = LDBL_MIN * copysignl(LDBL_MIN, x);
else if (k == 0x7fff)
dummy = LDBL_MAX * copysignl(LDBL_MAX, x);
}
#endif
return (x);
}